Forecast Discussions mentioning "ACARS", "MDCRS", "AIRCRAFT", "TAMDAR", or "AMDAR" received at FSL on 01/05/07

.AVIATION... VFR WILL CONT THROUGH THE PD. INCREASING PRESSURE GRADIENT AND DEEPENING MIXED LYR TODAY AND THURSDAY WILL LEAD TO SFC WND GUSTS AOA 25KTS. AS LOW PRESSURE MOVES NORTHEAST OUT OF THE SOUTHWEST US...IT WILL SPREAD CLOUDS NORTHWARD INTO THE AREA. THESE CLOUDS SHOULD BEGIN TO MANIFEST THEMSELVES LATE IN THE FORECAST PERIOD...BUT REMAIN IN THE VFR CATEGORY. &&

.SHORT TERM... TRANQUIL PD AS SFC HIGH PRES SHIFTS EWD ACRS THE OH VALLEY IN RESPONSE TO DEEPENING LOW PRES PROGRESSING ACRS SRN CANADA INTO THU. TIGHTENING GRADIENT WILL LEAD TO A BREEZY DAY BY LATE MORNING THOUGH THIS AFTN AS DEEPENING MIXED LYR TAPS INTO HIGHER MOMENTUM ALOFT SEEN ON UPSTREAM PROFILERS AND TAMDAR SNDGS OUT OF KORD. OTHERWISE INCREASING SW FLW WILL YIELD TEMPS ABT A CATEGORY WARMER THEN YDA GIVEN CONTD WAA AND ALBEIT WK JAN INSOLATION BUT NOT TO THE EXTENT OF IMPLIED 00Z GUIDANCE NUMBERS WHICH CONT TO RUN A BIT WARM. &&

.LONG TERM... THURSDAY THROUGH TUESDAY

FIRST CONCERN IN THE LONG TERM IS POTENTIAL HEAVY RAINFALL EVENT LATE THIS WEEK...ESPECIALLY ACROSS THE SE HALF OF THE CWA. WATER VAPOR IMAGERY THIS MORNING SHOWING YET ANOTHER CUTOFF LOW SPINNING ACROSS NORTHERN PORTIONS OF OLD MEXICO. THIS SYSTEM IS BEGINNING TO TAP INTO SUBTROPICAL MOISTURE AS EVIDENT BY BURGEONING MOISTURE PLUME OVER THE TEXAS GULF COAST DOWNSTREAM OF CUTOFF. THIS SYSTEM...AND ASSOCIATED PLUME OF SUBTROPICAL MOISTURE IS FORECAST BY MODEL GUIDANCE TO LIFT NE IN REPONSE TO UPSTREAM HEIGHT FALLS ALONG THE WEST COAST AS ADDITIONAL PACIFIC ENERGY MAKES LANDFALL. NAM-WRF HAS INITIALIZED THE NORTHERN STREAM POORLY AND THIS IS LIKELY HAVING A DETRIMENTAL EFFECT ON ITS INTERPLAY BETWEEN THE NORTHERN STREAM AND THE MEXICO CUTOFF...AND THUS ITS SOLUTION WAS NOT CONSIDERED A VIABLE SOURCE OF GUIDANCE FOR THIS FORECAST CYCLE.

FOLLOWING THE PREFERRED GFS/GEM SOLUTIONS...HAVE INTRODUCED POPS INTO THU PM FOR THE SOUTHERN HALF OF THE CWA AS LOW LEVEL THETA-E ADVECTION ADVANCES NORTH INTO THE OHIO VALLEY. DEEPER MOISTURE REMAINS LARGELY SOUTH OF THE CWA...HOWEVER RIGHT ENTRANCE REGION JET DYNAMICS MAY AID IN SPREADING LIGHT SHRA NORTHWARD INTO THE RETREATING DRY AIRMASS. LOW LEVEL THETA-E SURGE INCREASES THU NGT INTO FRI IN RESPONSE TO BACKING LOW/MID LEVEL FLOW IN ADVANCE OF EJECTING MEXICO CUTOFF. INCREASING LOW LEVEL FRONTAL REPONSE COUPLED WITH LARGE SCALE FORCING FOR ASCENT SHOULD PRODUCE A WIDESPREAD RAINFALL EVENT. LOCATION STILL SOMEWHAT UNCERTAIN GIVEN COMPLEX INTERACTION OF NORTHERN/SOUTHERN STREAMS AND PLACEMENT OF LOW LEVEL BAROCLINIC ZONE...HOWEVER ATTM BEST CHANCES FOR HEAVIER RAINFALL AMOUNTS APPEARS TO BE ACROSS THE SE HALF OF THE CWA...AGAIN FOLLOWING FAVORED GFS/GEM SOLUTIONS. HAVE INCREASED POPS TO LIKELY IN THESE AREAS...TAPERING BACK TO CHANCE NW. MAIN SURGE OF SUBTROPICAL MOISTURE WILL BE EAST OF THE CWA BY FRI NGT...HOWEVER PASSAGE OF MID LEVEL TROUGH AND COLD FRONT FRI NGT OR SAT JUSTIFIES KEEPING LOW CHANCE POPS FROM CONTINUITY.

EARLY NEXT WEEK THE FIRST INSTALLMENT OF WHAT LOOKS TO BE A MAJOR PATTERN CHANGE BEGINS TO APPEAR. INTENSE EAST ASIAN JET HAS BEEN WEAKENING OVER THE PAST WEEK AS THE LARGE SCALE HEIGHT ANOMALIES SUPPORTING IT BEGIN TO SHIFT AND WEAKEN. THE WEAKENING OF THE ONSLAUGHT OF PACIFIC SYSTEMS INTO THE WEST IS FORECAST TO ALLOW THE PATTERN TO AMPLIFY ACROSS NOAM EARLY NEXT WEEK...WITH THE MAJORITY OF OPERATIONAL AND ENSEMBLE GUIDANCE DROPPING A SIGNIFICANT NORTHERN STREAM SHORTWAVE INTO THE GREAT LAKES AND ALLOWING MORE SEASONABLE TEMPS/THICKNESSES TO MAKE AN APPEARANCE. OPERATIONAL GFS APPEARS TO BE ONE OF THE LEAST AMPLIFIED OF ALL RECENT ENSEMBLE GUIDANCE...AND HAVE THUS CONTINUED TREND OF GOING BELOW MEX GUIDANCE TEMPS MON/TUE. HAVE NOT INTRODUCED POPS JUST YET GIVEN TIMING/AMPLITUDE DIFFERENCES OF SMALLER SCALE FEATURES...HOWEVER IF CURRENT MODEL TRENDS CONTINUE WILL LIKELY NEED TO ADD A CHANCE OF SNOW TO EARLY NEXT WEEK... ESPECIALLY DOWNWIND OF LAKE MICHIGAN.

&&

.IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THURSDAY FOR LMZ043-LMZ046.

&&

$$

SHORT TERM...HOLSTEN LONG TERM...HITCHCOCK AVIATION...EDDY

.AVIATION... VFR WILL CONT THROUGH THE PD. INCREASING GRADIENT AND DEEPENING MIXED LYR FM MID MORNING INTO THIS AFTN WILL LEAD TO SFC WND GUSTS AOA 20KTS. &&

.SHORT TERM... TRANQUIL PD AS SFC HIGH PRES SHIFTS EWD ACRS THE OH VALLEY IN RESPONSE TO DEEPENING LOW PRES PROGRESSING ACRS SRN CANADA INTO THU. TIGHTENING GRADIENT WILL LEAD TO A BREEZY DAY BY LATE MORNING THOUGH THIS AFTN AS DEEPENING MIXED LYR TAPS INTO HIGHER MOMENTUM ALOFT SEEN ON UPSTREAM PROFILERS AND TAMDAR SNDGS OUT OF KORD. OTHERWISE INCREASING SW FLW WILL YIELD TEMPS ABT A CATEGORY WARMER THEN YDA GIVEN CONTD WAA AND ALBEIT WK JAN INSOLATION BUT NOT TO THE EXTENT OF IMPLIED 00Z GUIDANCE NUMBERS WHICH CONT TO RUN A BIT WARM. &&

.LONG TERM... THURSDAY THROUGH TUESDAY

FIRST CONCERN IN THE LONG TERM IS POTENTIAL HEAVY RAINFALL EVENT LATE THIS WEEK...ESPECIALLY ACROSS THE SE HALF OF THE CWA. WATER VAPOR IMAGERY THIS MORNING SHOWING YET ANOTHER CUTOFF LOW SPINNING ACROSS NORTHERN PORTIONS OF OLD MEXICO. THIS SYSTEM IS BEGINNING TO TAP INTO SUBTROPICAL MOISTURE AS EVIDENT BY BURGEONING MOISTURE PLUME OVER THE TEXAS GULF COAST DOWNSTREAM OF CUTOFF. THIS SYSTEM...AND ASSOCIATED PLUME OF SUBTROPICAL MOISTURE IS FORECAST BY MODEL GUIDANCE TO LIFT NE IN REPONSE TO UPSTREAM HEIGHT FALLS ALONG THE WEST COAST AS ADDITIONAL PACIFIC ENERGY MAKES LANDFALL. NAM-WRF HAS INITIALIZED THE NORTHERN STREAM POORLY AND THIS IS LIKELY HAVING A DETRIMENTAL EFFECT ON ITS INTERPLAY BETWEEN THE NORTHERN STREAM AND THE MEXICO CUTOFF...AND THUS ITS SOLUTION WAS NOT CONSIDERED A VIABLE SOURCE OF GUIDANCE FOR THIS FORECAST CYCLE.

FOLLOWING THE PREFERRED GFS/GEM SOLUTIONS...HAVE INTRODUCED POPS INTO THU PM FOR THE SOUTHERN HALF OF THE CWA AS LOW LEVEL THETA-E ADVECTION ADVANCES NORTH INTO THE OHIO VALLEY. DEEPER MOISTURE REMAINS LARGELY SOUTH OF THE CWA...HOWEVER RIGHT ENTRANCE REGION JET DYNAMICS MAY AID IN SPREADING LIGHT SHRA NORTHWARD INTO THE RETREATING DRY AIRMASS. LOW LEVEL THETA-E SURGE INCREASES THU NGT INTO FRI IN RESPONSE TO BACKING LOW/MID LEVEL FLOW IN ADVANCE OF EJECTING MEXICO CUTOFF. INCREASING LOW LEVEL FRONTAL REPONSE COUPLED WITH LARGE SCALE FORCING FOR ASCENT SHOULD PRODUCE A WIDESPREAD RAINFALL EVENT. LOCATION STILL SOMEWHAT UNCERTAIN GIVEN COMPLEX INTERACTION OF NORTHERN/SOUTHERN STREAMS AND PLACEMENT OF LOW LEVEL BAROCLINIC ZONE...HOWEVER ATTM BEST CHANCES FOR HEAVIER RAINFALL AMOUNTS APPEARS TO BE ACROSS THE SE HALF OF THE CWA...AGAIN FOLLOWING FAVORED GFS/GEM SOLUTIONS. HAVE INCREASED POPS TO LIKELY IN THESE AREAS...TAPERING BACK TO CHANCE NW. MAIN SURGE OF SUBTROPICAL MOISTURE WILL BE EAST OF THE CWA BY FRI NGT...HOWEVER PASSAGE OF MID LEVEL TROUGH AND COLD FRONT FRI NGT OR SAT JUSTIFIES KEEPING LOW CHANCE POPS FROM CONTINUITY.

EARLY NEXT WEEK THE FIRST INSTALLMENT OF WHAT LOOKS TO BE A MAJOR PATTERN CHANGE BEGINS TO APPEAR. INTENSE EAST ASIAN JET HAS BEEN WEAKENING OVER THE PAST WEEK AS THE LARGE SCALE HEIGHT ANOMALIES SUPPORTING IT BEGIN TO SHIFT AND WEAKEN. THE WEAKENING OF THE ONSLAUGHT OF PACIFIC SYSTEMS INTO THE WEST IS FORECAST TO ALLOW THE PATTERN TO AMPLIFY ACROSS NOAM EARLY NEXT WEEK...WITH THE MAJORITY OF OPERATIONAL AND ENSEMBLE GUIDANCE DROPPING A SIGNIFICANT NORTHERN STREAM SHORTWAVE INTO THE GREAT LAKES AND ALLOWING MORE SEASONABLE TEMPS/THICKNESSES TO MAKE AN APPEARANCE. OPERATIONAL GFS APPEARS TO BE ONE OF THE LEAST AMPLIFIED OF ALL RECENT ENSEMBLE GUIDANCE...AND HAVE THUS CONTINUED TREND OF GOING BELOW MEX GUIDANCE TEMPS MON/TUE. HAVE NOT INTRODUCED POPS JUST YET GIVEN TIMING/AMPLITUDE DIFFERENCES OF SMALLER SCALE FEATURES...HOWEVER IF CURRENT MODEL TRENDS CONTINUE WILL LIKELY NEED TO ADD A CHANCE OF SNOW TO EARLY NEXT WEEK... ESPECIALLY DOWNWIND OF LAKE MICHIGAN.

&&

.IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THURSDAY FOR LMZ043-LMZ046.

&&

$$

SHORT TERM/AVIATION...HOLSTEN LONG TERM....HITCHCOCK

.SHORT TERM... TRANQUIL PD AS SFC HIGH PRES SHIFTS EWD ACRS THE OH VALLEY IN RESPONSE TO DEEPENING LOW PRES PROGRESSING ACRS SRN CANADA INTO THU. TIGHTENING GRADIENT WILL LEAD TO A BREEZY DAY BY LATE MORNING THOUGH THIS AFTN AS DEEPENING MIXED LYR TAPS INTO HIGHER MOMENTUM ALOFT SEEN ON UPSTREAM PROFILERS AND TAMDAR SNDGS OUT OF KORD. OTHERWISE INCREASING SW FLW WILL YIELD TEMPS ABT A CATEGORY WARMER THEN YDA GIVEN CONTD WAA AND ALBEIT WK JAN INSOLATION BUT NOT TO THE EXTENT OF IMPLIED 00Z GUIDANCE NUMBERS WHICH CONT TO RUN A BIT WARM. &&

.LONG TERM... THURSDAY THROUGH TUESDAY

FIRST CONCERN IN THE LONG TERM IS POTENTIAL HEAVY RAINFALL EVENT LATE THIS WEEK...ESPECIALLY ACROSS THE SE HALF OF THE CWA. WATER VAPOR IMAGERY THIS MORNING SHOWING YET ANOTHER CUTOFF LOW SPINNING ACROSS NORTHERN PORTIONS OF OLD MEXICO. THIS SYSTEM IS BEGINNING TO TAP INTO SUBTROPICAL MOISTURE AS EVIDENT BY BURGEONING MOISTURE PLUME OVER THE TEXAS GULF COAST DOWNSTREAM OF CUTOFF. THIS SYSTEM...AND ASSOCIATED PLUME OF SUBTROPICAL MOISTURE IS FORECAST BY MODEL GUIDANCE TO LIFT NE IN REPONSE TO UPSTREAM HEIGHT FALLS ALONG THE WEST COAST AS ADDITIONAL PACIFIC ENERGY MAKES LANDFALL. NAM-WRF HAS INITIALIZED THE NORTHERN STREAM POORLY AND THIS IS LIKELY HAVING A DETRIMENTAL EFFECT ON ITS INTERPLAY BETWEEN THE NORTHERN STREAM AND THE MEXICO CUTOFF...AND THUS ITS SOLUTION WAS NOT CONSIDERED A VIABLE SOURCE OF GUIDANCE FOR THIS FORECAST CYCLE.

FOLLOWING THE PREFERRED GFS/GEM SOLUTIONS...HAVE INTRODUCED POPS INTO THU PM FOR THE SOUTHERN HALF OF THE CWA AS LOW LEVEL THETA-E ADVECTION ADVANCES NORTH INTO THE OHIO VALLEY. DEEPER MOISTURE REMAINS LARGELY SOUTH OF THE CWA...HOWEVER RIGHT ENTRANCE REGION JET DYNAMICS MAY AID IN SPREADING LIGHT SHRA NORTHWARD INTO THE RETREATING DRY AIRMASS. LOW LEVEL THETA-E SURGE INCREASES THU NGT INTO FRI IN RESPONSE TO BACKING LOW/MID LEVEL FLOW IN ADVANCE OF EJECTING MEXICO CUTOFF. INCREASING LOW LEVEL FRONTAL REPONSE COUPLED WITH LARGE SCALE FORCING FOR ASCENT SHOULD PRODUCE A WIDESPREAD RAINFALL EVENT. LOCATION STILL SOMEWHAT UNCERTAIN GIVEN COMPLEX INTERACTION OF NORTHERN/SOUTHERN STREAMS AND PLACEMENT OF LOW LEVEL BAROCLINIC ZONE...HOWEVER ATTM BEST CHANCES FOR HEAVIER RAINFALL AMOUNTS APPEARS TO BE ACROSS THE SE HALF OF THE CWA...AGAIN FOLLOWING FAVORED GFS/GEM SOLUTIONS. HAVE INCREASED POPS TO LIKELY IN THESE AREAS...TAPERING BACK TO CHANCE NW. MAIN SURGE OF SUBTROPICAL MOISTURE WILL BE EAST OF THE CWA BY FRI NGT...HOWEVER PASSAGE OF MID LEVEL TROUGH AND COLD FRONT FRI NGT OR SAT JUSTIFIES KEEPING LOW CHANCE POPS FROM CONTINUITY.

EARLY NEXT WEEK THE FIRST INSTALLMENT OF WHAT LOOKS TO BE A MAJOR PATTERN CHANGE BEGINS TO APPEAR. INTENSE EAST ASIAN JET HAS BEEN WEAKENING OVER THE PAST WEEK AS THE LARGE SCALE HEIGHT ANOMALIES SUPPORTING IT BEGIN TO SHIFT AND WEAKEN. THE WEAKENING OF THE ONSLAUGHT OF PACIFIC SYSTEMS INTO THE WEST IS FORECAST TO ALLOW THE PATTERN TO AMPLIFY ACROSS NOAM EARLY NEXT WEEK...WITH THE MAJORITY OF OPERATIONAL AND ENSEMBLE GUIDANCE DROPPING A SIGNIFICANT NORTHERN STREAM SHORTWAVE INTO THE GREAT LAKES AND ALLOWING MORE SEASONABLE TEMPS/THICKNESSES TO MAKE AN APPEARANCE. OPERATIONAL GFS APPEARS TO BE ONE OF THE LEAST AMPLIFIED OF ALL RECENT ENSEMBLE GUIDANCE...AND HAVE THUS CONTINUED TREND OF GOING BELOW MEX GUIDANCE TEMPS MON/TUE. HAVE NOT INTRODUCED POPS JUST YET GIVEN TIMING/AMPLITUDE DIFFERENCES OF SMALLER SCALE FEATURES...HOWEVER IF CURRENT MODEL TRENDS CONTINUE WILL LIKELY NEED TO ADD A CHANCE OF SNOW TO EARLY NEXT WEEK... ESPECIALLY DOWNWIND OF LAKE MICHIGAN.

&&

.AVIATION... VFR WILL CONT THROUGH THE PD. SW FLW WILL CONT TO INCREASE IN RESPONSE TO TIGHTENING SFC GRADIENT BTWN DEPARTING SFC ANTICYCLONE SHIFTING INTO THE TN VALLEY AND RATHER DEEP SFC LOW PRES TRAVERSING SRN CANADA INTO THU. DOES NOT APPEAR THAT EARLIER STRATUS POTENTIAL WILL MATERIALIZE GIVEN SOME DEGREE OF BL MIXING OCCURRING EVEN AT THIS HOUR WITHIN SHALLOW MOIST LYR SEEN PER RECENT TAMDAR SNDGS OUT OF KORD AND AS SUCH WILL NIX THAT MENTION. OTHERWISE DEEPENING MIXED LYR FM MID MORNING INTO AFTN WILL LEAD TO SFC WND GUSTS AOA 20KTS. &&

.IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THURSDAY FOR LMZ043-LMZ046.

&&

$$

SHORT TERM/AVIATION...HOLSTEN LONG TERM....HITCHCOCK

.AVIATION... VFR WILL CONT THROUGH THE PD. SW FLW WILL CONT TO INCREASE IN RESPONSE TO TIGHTENING SFC GRADIENT BTWN DEPARTING SFC ANTICYCLONE SHIFTING INTO THE TN VALLEY AND RATHER DEEP SFC LOW PRES TRAVERSING SRN CANADA INTO THU. DOES NOT APPEAR THAT EARLIER STRATUS POTENTIAL WILL MATERIALIZE GIVEN SOME DEGREE OF BL MIXING OCCURRING EVEN AT THIS HOUR WITHIN SHALLOW MOIST LYR SEEN PER RECENT TAMDAR SNDGS OUT OF KORD AND AS SUCH WILL NIX THAT MENTION. OTHERWISE DEEPENING MIXED LYR FM MID MORNING INTO AFTN WILL LEAD TO SFC WND GUSTS AOA 20KTS. &&

.PREV DISCUSSION... SHORT TERM... TONIGHT AND WEDNESDAY. QUIET WX CONTINUES THROUGH SHORT TERM. SOME PATCHES OF DENSE FOG THIS AM IN RIVER VALLEYS...HOWEVER WITH INCREASINGLY STRONG/CONFLUENT LOW LEVEL FLOW THROUGH THE PERIOD...BL SHOULD REMAIN SUFFICIENTLY MIXED TO PRECLUDE BR/FG FORMATION AND CONTINUE NIL WX. GAVE MORE SW-NE GRADIENT PER 925MB THERMAL PLAN VIEW/AND SLIGHT BOOST TO TEMPS WITH NEAR FULL SUN/DRY AFTN 1000-850MB LAYER WITH DD 20-25C...AND SIMILAR TO TIGHT MOS SCATTER. SHOULD AT LEAST REALIZE NEAR DRY AD TO NEAR 925MB TMWR AFT WITH SOME STRONGER WIND GUSTS. INCREASED SWRLY FLOW FOR SCA CONDITIONS BEYOND 09Z.

LONG TERM... WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FOCUS WILL BE ON PRECIP CHANCES POTENTIALLY ARRIVING AS EARLY AS THURS NGT AND CONTINUING INTO SATURDAY. HIGH PRESSURE WILL MOVE WELL EAST OF THE AREA WITH GULF BEGINNING TO OPEN UP IN RESPONSE TO TROUGH STARTING TO DIG IN CENTRAL US. MODELS HAVE VARIED GREATLY IN TERMS OF EFFECTS OF UPPER LEVEL ENERGY AND DEVELOPMENT OF SFC REFLECTION AS WELL AS TIMING OF THESE FEATURES. WHILE THE 500 MB CLOSED LOW LOOKS TO REMAIN ALONG THE GULF STATES INCREASING SW FLOW WILL DRAW IN MSTR RATHER RAPIDLY BEGINNING ON THURSDAY. MODELS VARY ON DEGREE OF MSTR AND OVERALL TRACK OF SYSTEMS BUT DO AGREE ON INCREASING ISENTROPIC LIFT BY THURS NGT ACROSS MAINLY SE AREAS. PREVIOUS SHIFT ADDED POPS IN FOR THIS TIME FRAME AND WILL MAINTAIN AND ACTUALLY EXPAND NW BUT KEEP IN CHC POP RANGE AS BEST MSTR RETURN WILL HOLD OFF UNTIL FRIDAY/FRIDAY EVENING AS JET DYNAMICS BECOME INVOLVED AND INCREASE CHANCE FOR PRECIP. 12Z NAM-WRF SUGGESTS SOME CONVECTIVE CONCERNS WITH K INDICES INCREASING IN TO THE LOW 30S BY LATE FRI AFTN AND SFC DEWPTS INTO THE LOW-MID 50S. NORMALLY WOULD BE RATHER SKEPTICAL OF THIS BUT CONSIDERING WHAT THE LAST SYSTEM BROUGHT IN TERMS ON CONVECTION AND THIS SYSTEM HAVING SOME SIMILARITIES...CAN`T BE ENTIRELY DISCOUNTED. DO THINK THAT QPF SHOWN BY NAM ON FRI IS RATHER OVERDONE WITH BULLSEYE OF NEARLY 1.5 INCHES OVER 12 HOURS. GFS KEEPS MSTR FURTHER SOUTH AS WELL AS CONVECTIVE POTENTIAL. HAVE OPTED TO INCREASE POPS SOME AS WELL ON FRIDAY BUT KEEP IN CHC CATEGORY AS WELL DESPITE SOME GUIDANCE SHOWING LIKELY/CAT POPS. WOULD LIKE TO SEE MORE TREND CONTINUE FOR A FEW MORE RUNS BEFORE JUMPING ON THINGS. TEMPS THROUGH SATURDAY WILL REMAIN WELL ABOVE NORMAL THROUGH FRIDAY AND THEN DROP BUT REMAIN A GOOD 5 TO 10 DEGREES ABOVE NORMAL. IF HIGHER DEWPTS CAN MATERIALIZE AS NAM-WRF SHOWS THEN INCREASE IN TEMPS WILL BE NEEDED FOR THEN.

BEYOND SATURDAY GULF MSTR WILL BE REMOVED FROM THE REGION AND LIKELY REMAIN THAT WAY THROUGH THE REMAINDER OF THE PERIOD. SEVERAL SYSTEMS ARE EXPECTED TO TRACK ACROSS THE AREA AS GENERAL TROUGH REMAINS IN PLACE. WITH AMOUNTS OF MSTR AND EXACT TRACKS QUESTIONABLE AT THIS POINT WITH ANY ONE WAVE...WILL MAINTAIN DRY FORECAST. SOME INDICATIONS REMAIN OF COLDER AIR ARRIVING FOR THIS PERIOD...BUT ANY ARCTIC INTRUSION WILL BE WELL AFTER THIS TIME FRAME.

&&

.IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY FROM 4 AM WEDNESDAY TO 7 PM EST THURSDAY FOR LMZ043-LMZ046.

&&

$$

SHORT TERM...MURPHY LONG TERM....FISHER AVIATION...HOLSTEN

.SHORT TERM /TONIGHT THROUGH THURSDAY/...

WATER VAPOR LOOP SHOWS A NORTHERN STREAM WAVE PASSING OVER THE NORTHERN MID ATLANTIC...FOLLOWED BY A WAVE MOVING EAST INTO THE EASTERN GREAT LAKES. A CUTOFF UPPER LOW IS SPINNING OVER NORTHERN MEXICO. ACARS 400-250MB WIND OBSERVATIONS REVEAL A 60-90KT WESTERLY JET FROM THE OHIO VALLEY EAST THROUGH THE NORTHERN MID ATLANTIC. 12Z SURFACE ANALYSIS PLACED A 1033MB ANTICYCLONE SPRAWLED ACROSS THE EAST COAST AND GULF STATES. A FRONTAL BOUNDARY HAS BECOME STATIONARY ACROSS THE CENTRAL GULF OF MEXICO...SOUTHERN FLORIDA AND OFF THE SOUTH CAROLINA COAST.

THE SKY WILL BEGIN CLEAR THIS EVENING...WITH HIGH LEVEL MOISTURE TRANSPORTING NORTHEAST INTO THE REGION AS THE UPPER LEVEL RIDGE AXIS PASSES OVERHEAD. AM SOMEWHAT CONCERNED ABOUT A MARINE AIRMASS CONSISTING OF LOW LEVEL STRATO-CU LOCATED ACROSS THE EASTERN CAROLINAS MAY ADVECT CLOSER TO THE REGION AS THE SURFACE HIGH MOVES OFF THE EAST COAST. WITH SOUTHWESTERLY BOUNDARY LAYER FLOW...BEST GUESS IS THAT THIS AIRMASS ONLY REACHES INTO SOUTHEAST VIRGINIA. LATER SHIFTS WILL HAVE TO MONITOR ITS PROGRESS.

ANOTHER GOOD DECOUPLING OPPORTUNITY TONIGHT WILL ALLOW TEMPERATURES TO FALL NEAR 30F (CONSIDERING WARM ADVECTION DURING THE PAST 24 HOURS). THERE COULD BE SOME LIGHT PATCHY FOG AS DEW POINTS ARE FORECAST TO JUMP DURING MORNING MIXING. TEMPERATURES ACROSS THE HIGHER TERRAIN ABOVE 2500 FEET WILL BE MUCH WARMER AS WINDS REMAIN SUSTAINED OVERNIGHT (IN THE LOWER 40S).

UPPER LEVEL MOISTURE CONTINUES TO OVERSPREAD THE MID ATLANTIC THURSDAY...BUILDING DOWN INTO THE MID LEVELS. AT THIS POINT AM GOING WITH SOME PARTIAL SUNSHINE...ESPECIALLY ACROSS CENTRAL MARYLAND. WITH ONLY SLIGHT WARM ADVECTION...TEMPERATURES ARE EXPECTED TO EASE TOWARD 60F THURSDAY WITH CONTINUED SOUTHWEST FLOW.

&&

.AVIATION /20Z-18Z/...

WINDS SLACKEN DIURNALLY WITH SUNSET. THERE COULD BE SOME LIGHT PATCHY FOG TOMORROW MORNING...SIMILAR TO AT KMRB THIS MORNING...UNDER DECENT RADIATIONAL COOLING CONDITIONS. UPPER LEVEL MOISTURE WILL BE INCREASING FROM THE SOUTHWEST LATE TONIGHT THROUGH TOMORROW.

HAVE NOTICED MARINE STRATO-CU ACROSS THE CAROLINAS. BELIEVE SOUTHWEST BOUNDARY LAYER FLOW WILL PREVENT THIS AIRMASS FROM REACHING THE TERMINALS...BUT ITS SOMETHING TO WATCH OVERNIGHT.

&&

.MARINE...

12Z GFS/ETA MOS AT THOMAS POINT BOTH SUGGEST SUSTAINED WINDS WILL INCREASE INTO THE 10 TO 15KT RANGE TOMORROW FROM 10KT OVERNIGHT. 12Z NAM/GFS PROXIMITY LAND BUFKIT FORECAST SOUNDINGS SUGGEST ADDITIONAL WIND GUST MOMENTUM MAY BRIEFLY REACH 18KT TOMORROW AFTERNOON. WILL KEEP WINDS BELOW SMALL CRAFT CRITERIA...IN THE 10 TO 15KT RANGE GIVEN SOUTHWEST WARM FLOW OVER MID 40 DEGREE WATER.

&&

.TIDES...

WATER LEVELS ARE CURRENTLY A HALF FOOT ABOVE ASTRONOMIC PREDICTIONS. THE LUNAR CYCLE IS AT A FULL MOON (100% FULL). THE CHESAPEAKE AND POTOMAC ARE RECOVERING FROM A BLOWOUT. BOTH THE CHESAPEAKE BAY OPERATIONAL FORECAST SYSTEM AND NOAA EXTRATROPICAL STORM SURGE MODEL GUIDANCE MAINTAIN CURRENT WATER LEVEL DEPARTURES THROUGH THE SHORT TERM.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...

BY THURSDAY NIGHT THE HIGH IS WELL OFF THE COAST AND RETURN FLOW IS STREAMING MOISTURE AND RAIN UP THE WEST SIDE OF THE APPS AND ALSO UP FROM THE SE STATES. CHCS FOR RAIN IMPROVE THROUGH THE NIGHT AND BY FRI MORNING RAIN IS CATEGORICAL POPS IN THE MOUNTAINS...LIKELY WEST OF THE BLUE RIDGE... AND HIGH CHC TO THE EAST.

LOW PRES WILL LIFT NORTH THRU THE MIDWEST FRIDAY AND FRI NIGHT MOVING A WARM FRONT TO OUR N BY SAT MORNING. RAIN IS LIKELY OR CATEGORICAL POPS FRIDAY... THEN JUST CHC FRI NIGHT AS THE FRONT LIFTS NORTH. NOT EXPECTING A DELUGE... BUT A DECENT RAIN WITH THE EVENT. EXPECTING BETWEEN A QUARTER AND THREE QUARTERS OF AN INCH OF RAIN BETWEEN THU NIGHT AND FRI NIGHT.

ALTHOUGH CONFIDENCE IS NOT EXCEPTIONALLY HIGH...SAT LOOKS TO BE A RATHER NICE DAY AT THE MOMENT. THE LOW LIFTS THE WARM FRONT INTO PA AND NORTHERN NJ...AND THE COLD FRONT STILL LAGS BACK OVER THE MISSISSIPPI RIVER. THAT SHOULD PUT US FIRMLY IN THE WARM SECTOR ASSUMING THE WARM FRONT TAKES THE HINT AND DOES INDEED PUSH UP TO OUR NORTH... ALWAYS A TROUBLE SPOT DURING THE COOL SEASON.

COLD FRONT PUSHES THRU LATE SAT NIGHT OR SUN MORN FOLLOWED BY MILD HIGH PRESSURE AGAIN. LATE SUN NIGHT OR MONDAY MORN A MORE SUBSTANTIAL COLD FRONT MOVES THROUGH WITH MORE SEASONABLE DAYTIME TEMPS IN THE 40S AND A CHC FOR SOME MINOR UPSLOPE SNOW SHOWERS IN THE MTNS FOR THE EARLY WEEK.

WINTER STILL NOWHERE TO BE FOUND IN THE EAST. THERE STILL IS A MASSING OF COLD AIR IN CANADA AND THE NORTHERN STATES FORECAST BY MID MONTH... BUT NOT AS COLD AS IT WAS FORECAST BY YESTERDAYS GFS RUN. IT CERTAINLY WOULD APPEAR THAT THE SECOND HALF OF JAN IS OUR CHANCE FOR REAL WINTER. WASHINGTON IS UP TO SIXTH AND BALTIMORE NINTH WARMEST PERIOD SINCE NOV 23RD THANKSGIVING...AND CLIMBING AS LONG AS WE KEEP UP THE LACK OF COLD AIR.

&&

.LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. &&

$$

SHORT TERM...ROGOWSKI LONG TERM...STRONG AVIATION...ROGOWSKI MARINE...ROGOWSKI TIDES...ROGOWSKI

.SHORT TERM... WATER VAPOR LOOP SHOWS A NORTHERN STREAM WAVE PASSING OVER THE NORTHERN MID ATLANTIC...FOLLOWED BY A WAVE MOVING EAST INTO THE EASTERN GREAT LAKES. A CUTOFF UPPER LOW IS SPINNING OVER NORTHERN MEXICO. ACARS 400-250MB WIND OBSERVATIONS REVEAL A 60-90KT WESTERLY JET FROM THE OHIO VALLEY EAST THROUGH THE NORTHERN MID ATLANTIC. 12Z SURFACE ANALYSIS PLACED A 1033MB ANTICYCLONE SPRAWLED ACROSS THE EAST COAST AND GULF STATES. A FRONTAL BOUNDARY HAS BECOME STATIONARY ACROSS THE CENTRAL GULF OF MEXICO...SOUTHERN FLORIDA AND OFF THE SOUTH CAROLINA COAST.

THE APPROACHING SHORTWAVE HAS BROUGHT A GOOD DEAL OF OPAQUE CIROSTRATUS THIS MORNING...ESPECIALLY ACROSS THE NORTHERN FORECAST AREA. THE PASSING OF THE WAVE WILL CLEAR OUT THE SKY ACROSS THE REGION FOR THE AFTERNOON.

THE ADVECTION SIGN HAS CHANGED FROM COLD TO WARM OVERNIGHT...WITH SOUTHWEST WINDS OCCURRING ON THE BACKSIDE OF THE SURFACE HIGH. 12Z KIAD RAOB AND MORNING ACARS SOUNDINGS INDICATE +3 TO 8C OF WARM ADVECTION BETWEEN 950MB AND 700MB DURING THE PAST 24 HOURS...WHICH SHOULD ALLOW TEMPERATURES TO NEAR 60F.

&&

.AVIATION... P6SM AS HIGH CLOUDS DEPART WITH PASSAGE OF UPPER LEVEL WAVE TODAY. SOUTHWEST WINDS WILL PREVAIL AROUND SURFACE HIGH MOVING OFF THE EAST COAST.

&&

.MARINE... 06Z GFS/00Z ETA MOS AT THOMAS POINT BOTH SUGGEST SUSTAINED WINDS WILL INCREASE INTO THE 10 TO 15KT RANGE THIS AFTERNOON. 06Z NAM/GFS PROXIMITY LAND BUFKIT FORECAST SOUNDINGS SUGGEST ADDITIONAL WIND GUST MOMENTUM MAY BRIEFLY REACH 18KT THIS AFTERNOON...WHILE 09Z KLWX WRF-NMM MARINE BUFKIT FORECAST SOUNDINGS DO NOT HAVE ANY WIND GUSTS ABOVE 16KT. WILL KEEP WINDS BELOW SMALL CRAFT CRITERIA...IN THE 10 TO 15KT RANGE GIVEN SOUTHWEST WARM FLOW OVER MID 40 DEGREE WATER.

&&

.TIDES... WATER LEVELS ARE CURRENTLY A HALF FOOT ABOVE ASTRONOMIC PREDICTIONS. THE LUNAR CYCLE IS AT A FULL MOON (100% FULL). THE CHESAPEAKE AND POTOMAC ARE RECOVERING FROM A BLOWOUT. BOTH THE CHESAPEAKE BAY OPERATIONAL FORECAST SYSTEM AND NOAA EXTRATROPICAL STORM SURGE MODEL GUIDANCE MAINTAIN CURRENT WATER LEVEL DEPARTURES THROUGH THE SHORT TERM.

&&

.LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE.

&&

$$

SHORT TERM/AVIATION/MARINE/TIDES...ROGOWSKI

.UPDATE... MAIN FCST CONCERN OVERNIGHT IS PCPN POTENTIAL AND PTYPE.

WATER VAPOR IMAGERY SHOWS MAIN SHORTWAVE TRACKING ENE INTO SRN MN...AND RADARS DEPICT AN INCREASING AREA OF RETURNS ACROSS CNTRL MN WITH A SCATTERING OF ECHOES SPREADING THRU UPPER MI ASSOCIATED WITH OTHER SUBTLE SHORTWAVES. SFC OBS SHOW PCPN REACHING THE GROUND IN MN...AND THERE HAS NO DOUBT BEEN SOME SPRINKLES OR LIGHT RAIN OCCURRING WITH THE ECHOES OVER UPPER MI GIVEN REFLECTIVITIES OF 40-45DBZ OVER THE ERN FCST AREA ON THE 0.5 DEGREE SLICE.

FAIRLY WELL-DEFINED APPEARANCE OF SHORTWAVE ON WATER VAPOR IMAGERY AND THE FACT THAT THERE HAS BEEN AN INCREASE IN RADAR REFLECTIVITIES AS WELL AS SFC OBS INDICATING PCPN SUGGEST POPS WILL NEED TO BE INCREASED OVERNIGHT. EXTRAPOLATION OF CURRENT PCPN AREA AND SHORTWAVE WOULD PUT MAIN PCPN AREA A BIT FARTHER E THAN WHAT INHERITED FCST INDICATES. AT THIS TIME...IT APPEARS MAIN AXIS OF PCPN WILL RUN FROM AROUND KIWD TO KCMX TO POSSIBLY AS FAR E AS MUNISING AND IRON RIVER. THIS IS SIMILAR TO TRACK OF BEST DEEP LAYER QVECTOR CONVERGENCE INDICATED BY 00Z RUC. AS FOR PTYPE...TEMPS WILL EVENTUALLY FLIRT WITH THE FREEZING MARK...BUT CURRENT SFC DWPT READINGS HERE AND UPSTREAM IN NRN WI WOULD SUGGEST THAT IT WILL BE DIFFICULT TO FALL BLO FREEZING. SO...DO NOT ANTICIPATE -FZRA TO BECOME A REAL ISSUE. ALOFT...EVENING TAMDAR SOUNDINGS FROM KCMX/KSAW INDICATE A NOSE OF COLD AIR IN THE SATURATED LAYER AROUND 4-4.5KFT WHERE TEMPS ARE -2 TO -3C. IF THE DRIER AIR ABOVE THAT LAYER IS MOISTENED...TEMP PROFILE WILL BE ALIGNED VERY CLOSE TO 0C. SO...RAIN AND/OR SNOW COULD BE PTYPE DOWN TO NEAR THE SFC. AS IT STANDS NOW...THERE LOOKS TO BE JUST ENOUGH WARM AIR NEAR THE SFC (ROUGHLY 1.4KFT THICK) TO LEAVE PCPN AS RAIN. HOWEVER...SINCE PROFILE IS VERY CLOSE TO BEING SUPPORTIVE OF ALL SNOW ABOVE THE NEAR SFC LAYER AND THE NEAR SFC LAYER COULD COOL SLIGHTLY...WILL OPT TO INCLUDE A MIX WITH SNOW FOR THE HIGHER TERRAIN AREAS NW OVERNIGHT WITH SNOW ACCUMULATIONS UP TO POSSIBLY 1 INCH.

&&

.PREV DISCUSSION... ISSUED AT 445 PM EST

UPPER AIR PATTERN CONSISTS OF A CLOSED 500 MB LOW OVER CENTRAL TX WITH TROUGHING IN THE PACIFIC NW AND NEAR LAKE WINNIPEG AND ACROSS ERN MT. THIS LAST SHORTWAVE WILL BE THE ONE TO AFFECT THE WEATHER TONIGHT AND THEN THE PACIFIC NW SHORTWAVE AFFECTS THE CWA ON FRI NIGHT AND SAT. NAM THEN SHOWS MORE TROUGHING FOR SUN.

NAM SHOWING 850-500 MB Q-VECTOR CONVERGENCE TONIGHT WITH SOME DEEP MOISTURE WHICH BOTH THE DYNAMICS AND THE MOISTURE MOVE OUT FRI MORNING. 850-500 MB Q-VECTOR CONVERGENCE AND MOISTURE THEN RETURN FOR SUN. NOT IMPRESSED TOO MUCH WITH RAIN CHANCES TONIGHT AND WENT WITH LOW CHANCE POPS BASED ON NO ISENTROPIC LIFT ON I280K-I295K SURFACES...BUT BETTER DYNAMICS ARRIVE LATER WITH SHORTWAVE AFTER MIDNIGHT...SO WOULD EXPECT THE BEST CHANCE FOR PCPN THEN. KEPT PCPN AS LIQUID AS TEMPERATURES WILL STAY ABOVE FREEZING AND COLDER AIR DOES NOT COME INTO THE WEST UNTIL LATE TONIGHT OR EVEN INTO FRI MORNING. 850 MB TEMPERATURES OFF THE GFS AND NAM ARE ALSO FORECASTED ABOUT 0C TO 2C AND 1000-850 MB THICKNESS VALUES ARE ABOVE 1305 METERS. THE MOISTURE AND DYNAMICS MOVE OUT FRI MORNING...SO PCPN SHOULD COME TO AN END.

FOR FRI NIGHT...LAKE EFFECT BECOMES A POSSIBILITY WITH THE NAM AND GFS BOTH DROPPING 850 MB TEMPERATURES DOWN TO -10C. THIS IS ENOUGH FOR LAKE EFFECT SNOW AS THE LAKE SUPERIOR WATER TEMPERATURES ARE 3C TO 4C AND THIS WOULD BE ENOUGH FOR LAKE EFFECT SNOW. THINGS SHOULD NOT GET TOO OUT OF HAND THOUGH AS THERE IS SOME DRY AIR AROUND AND AIRMASS IS NOT ALL THAT COLD AND THE WIND IS ALSO WESTERLY AT THAT TIME WHICH SHOULD KEEP BANDS OFFSHORE FOR THE MOST PART. THERE WILL ALSO BE A SHORTWAVE TO THE SOUTH WITH THE SOUTHERN CWA ON THE NORTH SIDE AND PCPN COULD BE MIXED AT THE BEGINNING NEAR THE LAKE MICHIGAN SHORELINE AND WE WILL BE ON THE NORTHERN END OF THE PCPN ON THIS ONE. KEPT SLIGHT CHANCE POPS IN FOR THE LAKE EFFECT AND CHANCE POPS FOR THE REST OF THE CWA.

AFTER THAT...KEEP GETTING MORE SHORTWAVES TO PASS BY AND TIMING OF THESE WILL BE DIFFICULT AND THERE WILL BE PERIODS OF LAKE EFFECT SNOW...BUT NOTHING REALLY BIG AT THIS TIME. TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL AND A FEW RECORD HIGHS COULD BE BROKEN ON FRIDAY BEFORE THE COOLDOWN BEGINS. WENT CLOSE TO ADJMVR AND ADJENS FOR TEMPERATURES.

IN THE EXTENDED...CANADIAN...ECMWF AND GFS ALL SHOW THE 500 MB PATTERN CONSISTS OF A TROUGH ACROSS THE CENTRAL U.S. INTO THE UPPER GREAT LAKES WITH RIDGING ON THE WEST COAST 00Z MON. TROUGHING REMAINS INTO 00Z TUE WITH RIDGING STARTING TO SLOWLY BUILD IN 00Z WED AND 00Z THU. WEAK TROUGHING THEN APPROACHES 00Z FRI. WILL GO DRY FOR WED WITH HIGH PRES BUILDING IN AND THEN KEEP LOW CHANCE POPS FOR MON THROUGH TUE NIGHT AND THEN HAVE SLIGHT CHANCE POPS IN FOR WED NIGHT AND THU. FOR TEMPERATURES...THEY STILL LOOK ABOVE NORMAL AND FOLLOWED A COMBO OF ADJENS...ADJMXR AND HPC GUIDANCE GRIDS FOR TEMPERATURES.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...NONE. &&

$$

ROLFSON (UPDATE) MICHELS (PREV DISCUSSION)

.AVIATION...

SATURATION OF LOWEST LEVELS IS UNDERWAY...FOLLOWING STRONG LOW LEVEL MOISTURE TRANSPORT DURING THE AFTERNOON WITH QUITE RAPID RAIN OVERSPREADING OF THE AREA INTO THE EARLY EVENING. GOOD AGREEMENT AMONG MODEL FORECAST SOUNDINGS/MOISTURE TIME SECTIONS IN LOWERING CEILINGS TO IFR BY LATE TONIGHT...THEN SLOW RECOVERY FRIDAY. TAMDAR SOUNDINGS THE PAST FEW HOURS ARE ALSO INDICATING A STEADY LOWERING OF CEILINGS/INCREASE IN LOW LEVEL MOISTURE.

00Z TAFS REFLECT STEADY RAIN UNTIL AROUND 07Z WHEN DEEPER MOISTURE DIMINISHES...WITH TAFS ALSO SHOWING DETERIORATING CONDITIONS INTO IFR TONIGHT. ONLY SLOW IMPROVEMENT IN CEILING HEIGHTS FRIDAY AS THERE REMAINS LOTS OF MOISTURE TRAPPED BENEATH STRENGTHENING INVERSION. RESTRICTIONS IN VISIBILITY SHOULD ALSO SLOWLY IMPROVE WITH MIXING ON FRIDAY.

&&

.PREV DISCUSSION...ISSUED 418 PM EST THU JAN 4 2007

SHORT TERM...TONIGHT AND FRIDAY

A NUMBER OF SHORTWAVES ARE MOVING ACROSS THE NORTHERN ROCKIES AND PLAINS TOWARDS THE UPPER MIDWEST...WHILE AN UPPER LEVEL CLOSED LOW CONTINUES TO MOVE EAST ACROSS TEXAS TOWARDS THE GULF COAST STATES. MOISTURE IS ADVECTING NORTH AHEAD OF THIS UPPER LOW UP THE MISSISSIPPI VALLEY WHILE A SURFACE HIGH REMAINS IN PLACE OVER THE SOUTHEASTERN COASTAL STATES. A SURFACE TROUGH EXTENDS FROM WESTERN ONTARIO TO THE CENTRAL PLAINS THAT WILL LIFT NORTHEAST ACROSS UPPER MICHIGAN TONIGHT.

AN AREA OF RAIN HAS DEVELOPED ACROSS ILLINOIS AND INDIANA WHERE THE FLOW THROUGH 700MB HAS BACKED TO THE SOUTH AND ISENTROPIC LIFT IS MAXIMIZED ON THE 295K SURFACE. THIS IS ALSO IN AN AREA OF GOOD Q-VECTOR CONVERGENCE THAT WILL LIFT ACROSS EXTREME SOUTHEAST MICHIGAN THIS EVENING. THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET WILL PROVIDE ADDITIONAL SUPPORT AND HAVE RAISED POPS FOR TONIGHT WITH A PERIOD OF RAIN EXPECTED FOR AREAS ALONG AND SOUTH OF ABOUT I-69. MOISTURE TRANSPORT VECTORS INDICATE THE BEST MOISTURE ADVECTION WILL ONLY REACH INTO NORTHERN OHIO...SO WILL CONTINUE TO TAPER POPS TO HIGH CHANCE ACROSS OUR EXTREME NORTHERN COUNTIES. TEMPERATURES WILL HAVE A HARD TIME FALLING TONIGHT AS SOUTHWESTERLY FLOW CONTINUES AHEAD OF THE APPROACHING SURFACE TROUGH. HAVE GENERALLY GONE A COUPLE DEGREES ABOVE GUIDANCE WITH SOME COOLING EXPECTED AS THE RAIN BEGINS.

BY FRIDAY MORNING...THE MID LEVEL DRYSLOT WILL MOVE OVER THE AREA LEAVING A LAYER OF MOISTURE BELOW 900MB. A DEEPER SURGE OF MOISTURE IS FORECAST TO LIFT INTO THE OHIO VALLEY ON FRIDAY BUT WILL REMAIN EAST OF THE LOW LEVEL TROUGH AXIS OVER LOWER MICHIGAN. WILL CONTINUE WITH JUST A CHANCE OF LIGHT RAIN SHOWERS AS WE REMAIN UNDER BROAD CYCLONIC FLOW. HIGH ON FRIDAY WILL BE WELL ABOVE NORMAL AGAIN WITH THE GREATER DETROIT AREA PEAKING NEAR 50F.

LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

REASONABLY GOOD CONSENSUS IN THE SPLIT FLOW PATTERN CONTINUING THROUGH THE WEEKEND BEFORE TRANSITIONING TO A NORTHERN STREAM DOMINATED LONG WAVE TROUGH SETTING UP OVER THE GREAT LAKES REGION EARLY NEXT WEEK. THE WEEKEND WILL MARK THE BEGINNING OF A TRANSITION TOWARD MORE TYPICAL JANUARY TYPE WEATHER...WITH MUCH COLDER AIR EXPECTED TO RESIDE OVER THE REGION THROUGH THE FIRST HALF OF NEXT WEEK. THEREAFTER...STRONG INDICATIONS ARE POINTING TOWARD A HIGHLY AMPLIFIED TROUGH BECOMING ESTABLISHED OVER THE WESTERN CONUS...WHICH WOULD KEEP THE RETURN TO WINTER QUITE BRIEF.

ON FRIDAY NIGHT...THE SOUTHERN STREAM TROUGH WILL CONTINUE TO GET SHEARED APART AS IT BECOMES FURTHER ABSORBED INTO THE WESTERLIES. A BUT SHOULD BE FAIRLY LIGHT. A SURFACE BOUNDARY WILL RESIDE OVER THE AREA THROUGH THE NIGHT WITHIN A WEAK SURFACE PRESSURE PATTERN. AT THE SAME TIME...A POSITIVELY TILTED UPPER TROUGH WILL BE ADVANCING FROM THE WEST. THIS INCREASED FLOW PATTERN WILL KICK A COLD FRONT THROUGH THE AREA SATURDAY MORNING. IT APPEARS AS THOUGH THE BEST DYNAMICS AND DEEP LAYER MOISTURE...ASSOCIATED WITH THE WEAKENING SOUTHERN WAVE...WILL REMAIN SOUTH OF THE REGION. HOWEVER...DESPITE THE LACK OF APPARENT DEEP LAYER MOISTURE...A STRONG 250 MB JET WILL BE OVERHEAD TO INTERACT WITH THE AFOREMENTIONED SURFACE BOUNDARY TO PROVIDE ENOUGH OF AN UPPER LEVEL DIVERGENCE/LOW LEVEL CONVERGENCE COUPLET TO FORCE SOME LIGHT PRECIP OVERNIGHT. THIS OPPORTUNITY WILL LINGER INTO SATURDAY MORNING AS THE COLD FRONT PASSES THROUGH. DRIER AND COLDER AIR WILL THEN MOVE IN...MAKING IT DIFFICULT TO SEE MUCH MORE THAN A FEW LIGHT SNOW SHOWERS/FLURRIES SATURDAY AFTERNOON. SHORT WAVE RIDGING WILL KEEP US DRY SATURDAY NIGHT AND SUNDAY.

A STRONGER COLD FRONT WILL PASS THROUGH SUNDAY NIGHT IN ADVANCE OF THE NORTHERN STREAM UPPER TROUGH MENTIONED IN THE FIRST PARAGRAPH. THIS WILL SEND 850 MB TEMPS TO AROUND -10C MONDAY MORNING. THE 12Z GFS INDICATES THAT A STRONG SHORTWAVE WILL WORK AROUND THE UPPER TROUGH AXIS ON TUESDAY...SENDING AN EVEN STRONGER COLD FRONT THROUGH THE REGION...WITH 850 TEMPS DROPPING BACK TO NEAR -15C TUESDAY EVENING. DESPITE LIMITED MOISTURE...WITH THE UPPER TROUGH AXIS IN THE VICINITY AND THE EXPECTATION OF THE TWO SURFACE FROPAS...WILL CONTINUE WITH A LOW CHANCE OF LIGHT SNOW FOR THE FIRST PART OF THE WORK WEEK. AT THIS TIME...THE BETTER CHANCE FOR PRECIP SEEMINGLY LOOKS TO OCCUR MONDAY NIGHT AHEAD OF THE STRONGEST COLD FRONT.

SOME MODERATION IS EXPECTED TO ENSUE BEYOND MIDWEEK AS A RETURN TO SOUTHWEST FLOW SEEMS LIKELY GIVEN THE LATEST CONSENSUS TOWARD A DEEP TROUGH OVER THE WEST COAST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON INCLUDING SAGINAW BAY...UNTIL 1 AM FRIDAY.

LAKE ST CLAIR...SMALL CRAFT ADVISORY...UNTIL 1 AM FRIDAY.

MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...UNTIL 1 AM FRIDAY.

&&

$$

AVIATION...DWD SHORT TERM...KAHL LONG TERM....SHULER

YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).

.UPDATE... IN THE NEAR TERM...HAVE UPDATED GRIDS TO INCLUDE HIGHER POPS/LIKELY ACROSS CENTRAL CWA THIS EVENING. NICE AREA OF RAIN MOVING INTO WEST CENTRAL MN NOW. ALL MODELS/18Z GFS/NAM_WRF AND 15Z SREF FROM SPC SHOW RATHER SIGNIFICANT BANDED STRUCTURE OF PRECIPITATION ACROSS CENTRAL MN THROUGH ABOUT 08Z OR SO. WILL DRAW AREA A LITTLE BIT FARTHER SOUTH...HOWEVER...AS RADAR TRENDS CONFIRM THAT MODELS MAY BE A BIT TOO FAR NORTH. OTHERWISE... TEMPERATURES ACROSS REGION OF RAIN ARE MAINLY 32-35F...AND ROAD SENSOR DATA ALL SHOW THIS TEMPERATURE TREND AS WELL. 00Z MPX SOUNDING SHOWS NICE WARM LAYER ABOUT 5500 FEET THICK OVER THE REGION. VARIOUS TAMDAR SOUNDINGS AROUND MPX AREA INDICATE THIS AS WELL. MODELS TREND SOME MODERATE FULL WIND FRONTOGENESIS OVER THE NORTHWEST QUAD OF CWA AS WELL...PROBABLY THROUGH ABOUT 08Z. AREA SEEMS TO HAVE DECREASED IN AREAL COVERAGE LAST HOUR OR SO AS IT MOVES INTO WESTERN MN. WITH AIR TEMPERATURES HOLDING IN THE SLIGHTLY ABOVE FREEZING CATEGORY...SIGNIFICANT FREEZING NOT ANTICIPATED AS PRECIPITATION IS FALLING. REFREEZE LATER TONIGHT ON UNTREATED SURFACES WILL BE GREATER THREAT. MAY SEE SOME WET SNOW ACCUMULATE LATER TONIGHT AS MORE SIGNIFICANT VERTICAL MOTION ARRIVES WITH SHORT WAVES TROUGH AXIS...MAINLY NORTH OF A LINE FROM NEAR BBB-STC-JMR. SHOULD RANGE AN INCH OR LESS HOWEVER AS SYSTEM IS RATHER FAST MOVING.

&&

.PREV DISCUSSION... /ISSUED 607 PM CST THU JAN 4 2007/

AVIATION...FOR 00Z TAF CYCLE. COMPLEX AVIATION FORECAST THROUGH TONIGHT...ESPECIALLY OVER THE FIRST FEW HOURS OF THE TAF AS CONDITIONS ARE EXPECTED TO DETERIORATE. SEVERAL AREAS OF CONCERN AT ISSUANCE. DECK OF 2 KFT CIGS FROM KRNH EASTWARD TO KEAU WILL CONTINUE...WITH SCT-BKN MVFR CONDITIONS ACROSS THE NORTHERN MSP METRO SATELLITE AIRPORTS NORTHWEST TO KSTC. KMSP AND SOUTHERN SATELLITE AIRPORTS CURRENTLY VFR WITH ONLY MID LEVEL CLOUDS FOR NOW. TOWARDS KAXN...CONDITIONS HAVE IMPROVED WITH VIS COMING UP TO AROUND 2 SM...WITH PATCHY 1/4 SM STILL HOLDING ON IN SPOTS. APPROACHING UPPER LEVEL ENERGY WILL SPREAD AREA OF MOISTURE AND FORCING INTO THE AREA THIS EVENING...WITH PRECIP CHANCES ENTERING FROM WEST TO EAST...WITH CIGS LOWERING/FILLING IN NEXT SEVERAL HOURS. PRECIP WILL BE LIGHT AND LIMITED IN COVERAGE...WITH 2 TO 4 HOUR WINDOW FOR BEST PRECIP CHANCES THIS EVENING AND EARLY TONIGHT INDICATED WITH TEMPO GROUPS. PRECIP TYPE EXPECTED TO BE RAIN EXCEPT AT KAXN AND KSTC WHERE COOLER AIR IS IN PLACE...WITH -FZRA POSSIBLE INITIALLY AT KAXN...AND -RASN AT KSTC. DRIER AIR WILL MOVE IN ALOFT EARLY FRIDAY...BUT EXPECT THAT MVFR CIGS WILL CONTINUE INTO THE LATE MORNING...WITH SCATTERING BY LATE AFTERNOON. WINDS WILL BE LIGHT THIS EVENING...WITH A TREND TOWARD BECOMING WESTERLY...THEN WNW BY FRIDAY MORNING. ..MDB..

PREV DISCUSSION... /ISSUED 330 PM CST THU JAN 4 2007/

IMMEDIATE FORECAST CONCERN IS WITH SWATH OF LIGHT PRECIPITATION THIS EVENING AND INTO THE OVERNIGHT HOURS ACROSS MAINLY CENTRAL MINNESOTA INTO N PORTIONS OF WISCONSIN CWA. WV IMAGERY SHOWS VORT MOVING ACROSS WESTERN SODAK ATTM. THIS FEATURE WILL MOVE QUICKLY EAST IN FAST ZONAL FLOW ACROSS AREA TONIGHT REACHING NW WI BEFORE DAYBREAK. METARS ACROSS SODAK HAVE SHOWN CLOUD BASES LOWERING DURING THE AFTN WITH SOME -RA NOW REACHING THE GROUND. SOME CONCERN AROUND AXN...MOX...LXL...JMR FOR FRZG RAIN AS AFTN TEMPERATURES HAVE ONLY REACHED THE LOWER AND MID 30S UNDER THICK CLOUDS AND FOG. AS PRECIP DIMINISHES AFTER 06Z...MAY BE ENOUGH COOLING FOR PRECIP TO END AS -SN. EVE SHIFT WILL HAVE TO WATCH FOR PSBL ADVY N CWA IF PRECIP BECOMES EXPANSIVE AND TEMPS DROP JUST A FEW DEGREES.

NEXT WAVE PULLING NE OUT OF THE S PLAINS ON FRIDAY NIGHT/SATURDAY MORNING IS TRENDING FARTHER SE...SO TRIMMED POPS TO ONLY A SMALL SLICE IN SC MN INTO WC WI.

LATER IN THE WEEKEND THE STRONG ZONAL FLOW ACROSS N TIER BEGINS TO ATTAIN MORE OF A WNW ORIENTATION WITH 500 MB HEIGHTS DROPPING ALMOST 200 METERS FROM TODAY TO 12Z TUESDAY. WEAK RIPPLES IN FLOW WILL BRING SOME SMALL CHANCES OF -SN. BEST OPPORTUNITY ATTM APPEARS TO BE ON MONDAY. WITH SUCCESSIVE RUNS OF GFS SHOWING DIFFERENCES IN TRACK USED A BROAD BRUSH OF 20% FOR NOW ACROSS THE AREA. TEMPERATURES TRENDING DOWNWARD THROUGH FORECAST...BUT STILL ABOVE EARLY JANUARY NORMS.

MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE.

&&

.MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. &&

$$

MDB/DWE

.SHORT TERM...TONIGHT THROUGH THURSDAY. CLOUD COVER AND A SLIGHT CHANCE OF SHOWERS IN THE NORTH CENTRAL PART OF THE STATE ARE THE MAIN FORECAST CHALLENGES THIS PERIOD. LOTS OF MIDDLE AND HIGH CLOUDS STREAMING ACROSS THE NORTHERN UNITED STATES ALL THE WAY FROM THE WEST COAST TO THE GREAT LAKES. WITH NEARLY ZONAL FLOW EXPECT THIS WILL CONTINUE. THE QUESTION IS WHETHER AN LOW CLOUDS WILL FORM LATE TONIGHT AND THURSDAY. THE MODELS HINT AT A STRATUS DECK LATE TONIGHT AND THURSDAY IN THE CENTRAL PART OF THE STATE. THAT SEEMS PLAUSIBLE BASED ON HIGHER DEWPOINTS MOVING UP FROM THE PLAINS...BUT TAMDAR SOUNDINGS FROM PEORIA...DES MOINES AND OMAHA ARE QUITE DRY. WOULD LIKE SOME REAL TIME SOUNDINGS FROM FURTHER SOUTH IN KANSAS AND MISSOURI BUT THE ARE NONE. PLAYED DOWN THE CHANCE OF THE LOW CLOUDS FOR NOW. LOW LEVEL JET WILL CONTINUE AGAIN TONIGHT SO INCLUDED LLWS IN THE TAFS AGAIN AFTER 00Z. THURSDAY/S HIGHS WILL DEPEND A LOT ON WHETHER LOW CLOUDS FORM OR NOT.

.LONG TERM...THU NGT THRU NXT WED. MAIN FCST CONCERN COMES AT THE END OF THIS WEEK AS A WEAK STORM PASSES TO OUR SE. DYNAMICS APR STG ENUF FOR SOME MINOR ACCUMULATIONS. OTHERWISE...MEAN FLOW TO START OFF WITH UPR RDGS OVR THE ERN PACIFIC AND ERN ATLANTIC WITH A BROAD UPR TROF OVR THE LWR 48 THIS WEEKEND INTO EARLY NXT WEEK. A NEW UPR TROF THEN PROGGED TO DIG ALONG THE WEST COAST TOWARD THE MIDDLE OF NXT WEEK WITH ANOTHER SURGE OF WARM AIR SPREADING ACROSS THE CNTRL U.S.

WEAK IMPULSE CONTS TO QUICKLY LIFT NORTH AND EAST THU EVENING TAKING BEST FORCING/MSTR ALONG WITH IT. HAVE KEPT A TOKEN POP FOR NRN WI...BUT HAVE REMOVED THE CHC POPS FROM THE REST OF NE WI. SW WNDS PLUS CLD CVR WL BRING ANOTHER MILD NGT TO THE RGN WITH UPR 20S N-CNTRL TO THE MID 30S NEAR LK MI. ATTN TURNS TO THE WEST WHERE A POSITIVELY-TILTED UPR TROF TO EXTEND FROM THE NRN PLAINS SWWD TO THE DESERT SW. A WEAK AREA OF LOW PRES OVR THE CNTRL PLAINS WL PRODUCE ISEN LIFT ALONG A BAROCLINIC ZN WHICH WL STRETCH FROM THE SRN PLAINS NWD ALL THE WAY TO THE UPR MIDWEST. LOW LVLS OF THE ATM INITIALLY ARE DRY AT 12Z FRI...BUT GRADUALLY SATURATE DURING THE DAY. CURRENT THINKING IS THAT ANY PCPN WOULD HAVE TO WAIT TIL THE ATM SATURATES MORE WHICH WOULD NOT BE UNTIL LATE FRI AFTERNOON. PREFER TO REMOVE POPS ALTOGETHER.

THE SFC LOW TRACKS NE TOWARD THE ERN GREAT LKS FRI NGT WITH DECENT AMTS OF WAA...FRONTOGENETICAL FORCING...Q-VEC CONVERGENCE AND FAVORABLE LEFT EXIT RGN OF THE UPR JET. ONLY THE SPD OF THE SYSTEM AND LACK OF DEEP MSTR IN PLACE WL KEEP THIS SYSTEM FROM REACHING HEADLINE PROPORTIONS. APRS THAT A BROAD 1 TO 3 INCH SNOW ACCUMULATION CAN BE EXPECTED ACROSS ALL OF NE WI. HAVE BUMPED POPS UP TO LIKELY OVR MOST OF THE FCST AREA AS A RESULT. SFC LOW CONTS TO PULL AWAY ON SAT WITH SOME LINGERING LGT SNOW SHWRS OR FLURRIES PSBL DURING THE MORNING HRS. BY SAT AFTERNOON...A WEAK SFC RDG APPROACHES ALONG WITH SUBSIDENCE AND DRIER AIR. HAVE REMOVED ANY PCPN WORDING FOR THE AFTERNOON ACROSS NE WI. DUE TO CAA...DO NOT SEE MUCH IN THE WAY OF DIURNAL WARMING AND HAVE KEPT TEMPS A COUPLE OF DEGS BLO THE MEX GUID.

THE SFC RDG QUICKLY SLIDES EAST BY SUNDAY ALLOWING FOR A CLIPPER-TYPE SYSTEM TO DIG SE TOWARD THE WRN GREAT LKS. MSTR APRS LIMITED AHD OF THIS SYSTEM THUS ANTICIPATE A LOW QPF EVENT. APRS TEMPS ALOFT WL BE COLD ENUF SUCH THAT ANY PCPN THAT DOES FALL WOULD BE ALL FROZEN...EVEN OVR E-CNTRL WI DESPITE SFC TEMPS IN THE MID 30S. LINGERING CHCS OF LIGHT SNOW OR FLURRIES TO CONT THRU SUNDAY NGT AS THE UPR TROF PASSES BY AND CYCLONIC FLOW TO RESIDE OVR THE RGN. CYCLONIC FLOW STILL IN OUR VCNTY HEADED INTO MON ALTHO BETTER MSTR WL HAVE ALREADY PULLED AWAY. WL LEAVE SOME FLURRIES ACROSS NE WI UNDER MOSTLY CLDY SKIES.

A NEW UPR TROF IS FCST TO BEGIN DIGGING SWD TOWARD THE PAC NW ON TUE WHICH WL IN EFFECT FLATTEN THE MEAN FLOW ACROSS THE LWR 48. THE GFS HINTS THAT ANOTHER CLIPPER LOW PRES AREA WL DROP THRU/EXIT THE RGN ON TUE...HOWEVER ECMWF/UKMET DO NOT HAVE THIS FEATURE AND ENSEMBLES HAVE A WIDE SPREAD. THEREFORE...PREFER TO KEEP TUE DRY FOR NOW WITH TEMPS STILL ABV NORMAL BY ABT 5 DEGS. AS THIS UPR TROF CONTS TO DIG SOUTH ALONG THE WEST COAST NXT WED...MEAN FLOW OVR THE GREAT LKS WL BECOME MORE SW WITH TIME. THIS WL ALLOW WARMER AIR ALOFT TO RETURN TO THE RGN WITH SFC TEMPS STARTING TO WARM AS WELL. NO PCPN YET AS THIS NEW SYSTEM ORGANIZES OVR THE WRN U.S.

&&

.GRB WATCHES/WARNINGS/ADVISORIES... NONE &&

$$ RDM/KALLAS WEATHER.GOV/GREENBAY

.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BRING SCATTERED SHOWERS...MOSTLY LIGHT...OVERNIGHT. WINDY CONDITIONS WILL OCCUR OVERNIGHT IN THE MOUNTAINS AND HIGH DESERTS AND OVER THE COASTAL WATERS. ONLY MINOR AMOUNTS OF SNOW ARE EXPECTED OVER THE HIGHER MOUNTAINS. AS THE SYSTEM MOVES EAST FRIDAY...SKIES WILL CLEAR...BUT STRONG GUSTY WINDS WILL DEVELOP THROUGH AND BELOW PASSES AND CANYONS...WITH STRONGEST WINDS BELOW THE CAJON PASS. AFTER A COOL DAY FRIDAY...A WARMING TREND WILL OCCUR THROUGH MONDAY AS OFFSHORE FLOW AND OCCASIONAL GUSTY WINDS THROUGH CANYONS CONTINUE. A STORM SYSTEM COULD AFFECT THE REGION LATE NEXT WEEK.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES...

SCATTERED SHOWERS HAD OVERSPREAD MOST AREAS EXCEPT FOR THE LOWER DESERTS. AMOUNTS WERE MOSTLY LESS THAN 1/10 INCH SO FAR...WITH THE SAN BERNARDINO COUNTY MTNS RECEIVING THE BEST PRECIP. IT APPEARS THERE ARE 2 WAVES WITH THIS SYSTEM...ONE MOVING THROUGH THE AREA NOW AND ANOTHER MOVING INTO NW LA COUNTY. ACARS SOUNDINGS SHOWED THE FREEZING LEVEL TO STILL BE AROUND 8000 FEET...THOUGH MINOR EVAPORATIVE COOLING COULD BRING THE SNOW LEVEL DOWN TO 6000 FEET IN THE NEXT HOUR OR TWO. THE COLD AIR WILL MOVE IN WITH THE SECOND WAVE...WHICH WILL MAINLY BRING A LITTLE MORE PRECIP TO HIGHER ELEVATIONS. THIS COULD BRING LOCAL AMOUNTS OF AN INCH OF SNOW ABOVE ABOUT 5000 FEET. TOTAL RAINFALL AMOUNTS OF 1/10 INCH AT THE COAST AND 1/4 INCH ON WEST MTN SLOPES STILL LOOKS GOOD...THOUGH THE SAN BERNARDINO COUNTY MTNS COULD GET LOCALLY OVER 1/4 INCH...ESPECIALLY WITH THE SECOND WAVE THAT WILL MOVE THROUGH AROUND MIDNIGHT. A 50 MPH GUST OCCURRED AT BURNS CANYON BEFORE 6 PM...BUT OVERALL...THE STRONGER WINDS...GREATER THAN 40 MPH...ARE PRETTY LOCALIZED. THE COLD FRONT OVER THE COASTAL WATERS IS SOMEWHAT WASHED OUT...BUT REGARDLESS...EXPECT SUPPORT FROM COLD AIR ADVECTION AND INCREASING WINDS ALOFT TO STRENGTHEN WINDS OVER THE COASTAL WATERS STARTING AROUND MIDNIGHT. SOME OF THESE WINDS COULD REACH THE IMMEDIATE COAST...BUT SPEEDS SHOULD STAY BELOW ADVISORY CRITERIA THERE.

PRECIP SHOULD END LATE TONIGHT...OR AT THE LATEST...AROUND SUNRISE FRIDAY OVER THE SOUTHERN SAN DIEGO COUNTY MTNS AS DRY AIR MOVES IN RAPIDLY FROM THE NORTH. WINDS WILL DEVELOP THROUGH/BELOW PASSES AND CANYONS...ESPECIALLY N-S ONES LIKE THE CAJON PASS FRI. MOST OF THE SUPPORT IS ALOFT...WITH SOME WINDS GREATER THAN 50 KNOTS IN THE 850-700 MB LAYER. COLD AIR ADVECTION WILL BE JUST MODERATE FRIDAY...SO THAT MIGHT LIMIT WINDS SOMEWHAT...PLUS THE PEAK WINDS ALOFT COME LATE FRI VS THE MORE CLIMATOLOGICALLY-DESIRED MORNING HOURS FRI. HOWEVER...THE 850-700 MB WINDS COMBINED WITH ABOUT A 15 MB SURFACE PRESSURE GRADIENT BETWEEN A HIGH IN NW NEVADA AND SAN DIEGO SHOULD BE ENOUGH FOR LOCAL GUSTS OVER 70 MPH. WINDS WILL NOT BE AS STRONG OVER SAN DIEGO COUNTY AS OVER COUNTIES FURTHER NORTH...BUT I WILL LET THE HIGH WIND WATCH CONTINUE FOR THE SAN DIEGO COUNTY MTNS AS LOCAL GUSTS NEAR 60 MPH COULD OCCUR. WINDS ALOFT AND AT THE SURFACE WILL GRADUALLY DECREASE LATE FRI NIGHT...BUT WIND ADVISORIES WILL PROBABLY BE NEEDED FROM WHEN THE HIGH WIND WATCH/WARNING EXPIRES FRI EVENING UNTIL SAT.

HIGH PRESSURE ALOFT WILL BECOME FAIRLY STRONG OVER THE E PAC AND THE SW US OVER THE WEEKEND AND EARLY NEXT WEEK...SO THAT COMBINED WITH NO MARINE LAYER SHOULD HELP DAYTIME TEMPS RISE TO 5-10 DEG F ABOVE NORMAL BY SUN/MON...THOUGH DRY AIR WILL RESULT IN SOME CHILLY NIGHTS WHERE IN WIND-SHELTERED LOCATIONS. SPEAKING OF THE DRY AIR...THAT WILL ELEVATE THE FIRE WEATHER HAZARD...AND THE FIRE WEATHER WATCH WILL LIKELY BE NEEDED THROUGH MONDAY AS OCCASIONAL GUSTY WINDS COULD CONTINUE BELOW PASSES/CANYONS...ESPECIALLY WITH ANOTHER INCREASE MONDAY.

GFS HAS A DEEP TROUGH FOR LATE NEXT WEEK WITH PRECIP CHANCES STARTING AROUND THU. ECM IS MUCH WEAKER THOUGH BUT STILL HAS A TROUGHY PATTERN. THERE IS THE POTENTIAL FOR APPRECIABLE RAIN AMOUNTS AND LOW SNOW LEVELS...THOUGH OF COURSE MODEL VERIFICATION IS STILL RATHER LOW ONE WEEK OUT...SO THINGS COULD CHANGE.

&&

.AVIATION...

CIGS/VSBYS HAVE BEEN LOWERING THROUGHOUT THE EVENING AT KSNA-KCRQ-KSAN- AND AT KONT. VSBYS AT KSAN...KCRQ...KSNA AND KONT HAVE DROPPED TO AT OR JUST AROUND 3 MI IN -SHRA. ONLY LIGHT AMOUNTS REPORTED...PRETTY MUCH AS EXPECTED. CIGS HAVE DROPPED A BIT BLO 1000 FT FOR A TIME WITH SOME OF THE RAIN. THE BACK EDGE OF THE RAIN IS NOT TOO FAR OFF THE COAST...SO VSBYS WILL IMPROVE BY AROUND 06Z.

ANOTHER ISSUE IS THE STRONG WIND SHIFT PREVIOUSLY EXPECTED WITH THE FRONT. APPEARS AS IT WILL BE MORE GRADUAL AND OF LESS IMPACT. THE FRONT HAS SHOWN SIGNS OF WEAKENING AS IT MOVED DOWN THE COAST. SO HAVE BACKED WINDS OFF AND KEPT THEM MORE WESTERLY VS NW AT COASTAL TAF LOCATIONS. SOME TURBULENCE PROBLEMS AND WAVE/ROTOR ACTIVITY ARE STILL POSSIBLE IN THE LEE OF THE MTNS OVERNIGHT. WINDS WILL TURN NORTHERLY EARLY FRI MORNING...WITH TURBULENCE AND WAVE/ROTOR ACTIVITY SOUTH OF THE SAN BERNARDINOS. CEILINGS WILL ALSO DISAPPEAR BY SUNRISE EXCEPT PERHAPS ON THE WINDWARD MTN FOOTHILLS.

&&

.MARINE... THE FRONT WILL BRING LARGE SWELL AND GALE FORCE WINDS THIS EVENING THROUGH FRI. THE COMBINATION OF THESE FEATURES WILL PRODUCE HAZARDOUS SEAS FOR MARINERS...SEE LAXMWSSGX...AND LARGE SURF FOR BEACH VISITORS...SEE LAXCFWSGX. SEAS AND WINDS WILL SLOWLY DECREASE FRI.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...

WIND ADVISORY UNTIL 4 AM FRIDAY...FOR MOST DESERTS AND MOUNTAINS...SEE LAXNPWSGX.

HIGH WIND WATCH FRIDAY FROM 6 AM TO 10 PM FRIDAY ...FOR ORANGE COUNTY...INLAND EMPIRE...AND ALL SW CALIFORNIA MOUNTAINS...SEE LAXNPWSGX.

FIRE WEATHER WATCH FRIDAY THROUGH MONDAY...FOR MOUNTAINS AND VALLEYS...SEE LAXRFWSGX.

SPECIAL WEATHER STATEMENT FOR THE COLD FRONT AND GUSTY WINDS...SEE LAXSPSSGX.

HIGH SURF ADVISORY UNTIL 10 PM PST FRI...FOR ORANGE COUNTY AND SAN DIEGO COUNTY COASTS...SEE LAXCFWSGX.

SMALL CRAFT ADVISORIES FOR THE INNER AND OUTER WATERS TONIGHT AND FRI FOR WINDS AND HAZARDOUS SEAS AND GALE WARNING FOR OUTER WATERS TONIGHT...SEE LAXCWFSGX.

&&

$$

PUBLIC...MAXWELL AVIATION/MARINE...PURPURA

.DISCUSSION...

345 AM CST

S/WV INDICATED BY WATER VAPOR IMAGERY LIFTING RAPIDLY NE ACROSS WRN/NRN GRTLKS RGN EARLY THIS AM. THIS S/WV TO MOV QUICKLY AWAY FROM FCST AREA EARLY THIS MORNING...WITH DEEPER MOISTURE ALREADY TO THE EAST AND RADAR DETECTABLE PCPN ALREADY DEPARTED. GOES 11-3.9 MICRON IMAGERY INDICATES EXTENSIVE LOW STRATUS DECK LINGERING ALONG AND EAST OF SFC TROUGH AXIS ACROSS EASTERN IA...WITH SOME EROSION OF THESE LOWER CLOUDS INTO WESTERN IL. MODEL FCSTS OF OMEGA/DIV-Q FIELDS INDICATE BEST SUBSIDENCE IN WAKE OF DEPARTING WAVE OCCURRING NOW...SO AM NOT OVERLY OPTIMISTIC THAT MUCH CLRG OF LOW CLOUDS WILL OCCUR WITH MODEL TSECTS MAINTAINING SATURATED LAYER BELOW ABOUT 900 HPA AS LOW LEVEL TROF/FRONTAL BOUNDARY DRIFTS ACROSS FCST AREA TODAY. HGTS BEGIN TO FALL AGAIN THIS AFTN...AS NXT S/WV LIFTS OUT OF PLAINS AND CONTINUES AMPLIFICATION OF UPPER FLOW OVER NRN/CNTRL PLAINS WHICH WILL LIKELY HELP TO MAINTAIN OR REFORM CLOUD COVER IN MOIST LLVL AIR MASS. WILL MAINTAIN CHANCE POPS WITH SYSTEM TNGT/SAT MRNG...WITH HIGHEST PROBABILITY NWRN CWA ALONG TRACK OF STRONGLY SHEARED VORT MAX ALNG CYCLONIC SHEAR SIDE OF UPPER JET AXIS. FCST SNDGS/PARTIAL THICKNESS VALUES INDICATE RAIN MAIN PCPN TYPE...WITH POTENTIAL FOR MIX OF RA/SN INTO NWRN COUNTIES AROUND RFD TOWARD SUNRISE SAT. NOT LIKELY TO SEE ANY ACCUM HOWEVER WITH RELATIVELY WEAK FORCING AND WARM LLVLS. PCPN EXPECTED TO END BEFORE NOON SAT AS S/WV CONTINUES TO RACE OFF TO THE NORTHEAST.

WEAK SFC HIGH PRESSURE RDG BUILDS IN SAT AFTN WITH SIGNIFICANT DRYING IN LLVLS BEHIND COLD FRONT. THUS EXPCT SOME CLRG FROM WEST DURG AFTN. CLDS XPCTD TO RETURN BY SUN MRNG HOWEVER...AS NXT S/WV IN THIS VRY ACTIVE FLOW PATTERN DVLPS WAA/ISENTROPIC UPGLIDE INTO WRN GRTLKS. MAIN FORCING WITH SUNDAY SYSTEM MOVES NORTH...WITH NAM/GFS BOTH KEEPING PRECIP NORTH OF IL/WI BORDER.

TEMP WISE...STARTING OUT 15 DEG ABOVE NORMAL MAXES THIS MRNG...SO ANOTHER JANUARY DAY NEAR 50 DEG. BUMPED EARLY MRNG TEMPS UP BASED ON CURRENT TRENDS. OTHERWISE...GUIDANCE PRETTY SIMILAR NEXT FEW DAYS SO NO BIG DEVIATIONS.

SHOULD NOTE THAT WED NGT/THURS RAINFALL HAS LED TO SOME RISES ON AREA RIVERS. HAVE BEEN WORKING WITH NCRFC OVRNGT ON UPDATED CREST FORECASTS ON ILLINOIS AND LITTLE CALUMET RIVER BASINS. SEE KLOT FLOOD OUTLOOKS/WATCHES/WARNINGS FOR COMPLETE DETAILS.

RATZER

&&

.AVIATION DISCUSSION... 1016 PM CST

THE SOUTH WIND WILL CONTINUE THROUGH EARLY MORNING. THE SURFACE TROUGH OVER MINNESOTA TO EASTERN IOWA AT 04 UTC. THIS TROUGH WILL MOVE THROUGH AROUND 21 UTC FRIDAY. THE PRECIPITATION IS EXPECTED TO MOVE EAST OF NORTHEAST ILLINOIS AND NORTHWEST INDIANA SOON AFTER MIDNIGHT. THE IFR CEILINGS WILL BE IN THE AREA THROUGH THE MORNING. THERE ARE MVFR AND SOME IFR CEILINGS ACROSS WISCONSIN AND MINNESOTA. THE VISIBILITY WILL BE 3 MILES OR BETTER AS LONG AS THE WIND MAINTAINS ITS SPEED. THE ACARS SOUNDING SHOW AN INVERSION AT 5990 FEET AT ORD AT 0315 UTC AND 4090 FEET AT RFD AT 0339 UTC. THERE IS A WIND 18 TO 28 KNOTS ABOVE 1620 FT. THE KINETIC ENERGY MAY STILL MIX DOWN TO THE SURFACE OVERNIGHT. THIS WILL MAINTAIN A WIND OF AROUND 10 TO 12 KNOTS. THE DAVENPORT SOUNDING AT 00 UTC SHOWS A SMALL DEWPOINT AND TEMPERATURE DIFFERENCE UP TO 4387 FT. THE FORECAST SOUNDING FROM THE LOCALLY RUN WRF ARW MODEL SHOWS NEAR EQUILIBRIUM OF WATER VAPOR CONCENTRATION IN THE AIR AT THE MORNING TEMPERATURE UP TO 2700 FEET. WE WILL KEEP THE FOG IN THE FORECAST FOR OVERNIGHT BUT AFTER 10 UTC AND IN THE FORM OF TEMPO GROUPS.

&&

.LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...GALE WARNING ENTIRE LAKE/NEARSHORE UNTIL 6PM CST THIS EVE. SMALL CRAFT ADVISORY IL AND IN WATERS 6PM TO MIDNIGHT TONITE.

&&

$$

.DISCUSSION... 310 PM CST

SHARPLY DELINEATED NW EDGE OF STRATIFORM RAIN EXTENDING FROM WAUKEGAN TO AMBOY ATTM IS HOLDING STEADY. LITTLE ADDITIONAL NWWD PROGRESSION EXPECTED...AS FAVORABLE QUADRANT OF H3 JET STREAK WHICH IS NOW IN PRIME LOCATION OVERHEAD PIVOTS/SHIFTS EWD LATE TONIGHT. 50KT LOW LEVEL JET CONTINUES TRANSPORTING VERY MOIST AIR INTO THE LOCAL AREA THROUGH EARLY EVENING. MODEL BUFR SOUNDINGS BRING H9 DEWPTS TO AROUND 9C BY 01Z...PRETTY UNUSUAL FOR JANUARY. NOW ACCUMULATING SFC WATER...SUBSTANTIAL AMOUNTS OF LINGERING LOW LEVEL ATMOSPHERIC MOISTURE...LESSENING WINDS...AND LATE NIGHT SUBSIDENCE...SHOULD COMBINE TO CREATE WIDESPREAD FOG LATE TONIGHT/TOMORROW MORNING.

SHORT-LIVED BREAK IN THE PRECIP LATE TONIGHT THROUGH THE DAY FRIDAY BEHIND THIS CURRENT DISTURBANCE. FRONTAL BOUNDARY CURRENTLY OVR WRN MN REACHES NRN IL BY FRI NT AS APPROACHING MID/UPR TROPOSPHERIC SHORTWAVE TROUGH ENHANCES THE SYNOPTIC SCALE LIFT. LESS LOW LEVEL MOISTURE FOR THIS NEXT DISTURBANCE TO TAP INTO...SO PRECIP SHOULD BE FAIRLY LIGHT FRI NT/SAT.

WK COLD ADVECTION BEGINS FRIDAY AFTN WITH SECONDARY REINFORCING COLD SHOT ARRIVING BEHIND A FRONT ON SATURDAY. LOW CENTER REMAINING NORTH OF THE CANADIAN BORDER WHILE MOST LOW LEVEL MOISTURE WILL BE TRAPPED OVR THE DEEP SOUTH...SO AM NOT ANTICIPATING PRECIP LOCALLY.

CLIPPER-LIKE SYSTEM DIVING OUT OF THE NRN PLAINS ON MONDAY MAY BRING PRECIP TO THE REGION ON MONDAY NT. KEPT SILENT 20 POP IN FOR NOW...BUT MAY NEED TO BOOST THAT ONCE WITH SUCCESSIVE FCSTS AS CONFIDENCE IN TIMING/LOCATION INCREASES. TEMPS SHOULD REMAIN ABV NORMAL THROUGH THE FCST PERIOD. BEYOND DAY 7...SIGNS ARE EMERGING THAT AT LEAST A PORTION OF THE ARCTIC COLD POOL WILL SHIFT FROM ALASKA AND SIBERIA INTO WRN CANADA AND NWRN CONUS. SO A TASTE OF SOMETHING MORE RESEMBLING WINTER MAY BE ON THE HORIZON.

HANDEL

&&

.AVIATION DISCUSSION... 1016 PM CST

THE SOUTH WIND WILL CONTINUE THROUGH EARLY MORNING. THE SURFACE TROUGH OVER MINNESOTA TO EASTERN IOWA AT 04 UTC. THIS TROUGH WILL MOVE THROUGH AROUND 21 UTC FRIDAY. THE PRECIPITATION IS EXPECTED TO MOVE EAST OF NORTHEAST ILLINOIS AND NORTHWEST INDIANA SOON AFTER MIDNIGHT. THE IFR CEILINGS WILL BE IN THE AREA THROUGH THE MORNING. THERE ARE MVFR AND SOME IFR CEILINGS ACROSS WISCONSIN AND MINNESOTA. THE VISIBILITY WILL BE 3 MILES OR BETTER AS LONG AS THE WIND MAINTAINS ITS SPEED. THE ACARS SOUNDING SHOW AN INVERSION AT 5990 FEET AT ORD AT 0315 UTC AND 4090 FEET AT RFD AT 0339 UTC. THERE IS A WIND 18 TO 28 KNOTS ABOVE 1620 FT. THE KINETIC ENERGY MAY STILL MIX DOWN TO THE SURFACE OVERNIGHT. THIS WILL MAINTAIN A WIND OF AROUND 10 TO 12 KNOTS. THE DAVENPORT SOUNDING AT 00 UTC SHOWS A SMALL DEWPOINT AND TEMPERATURE DIFFERENCE UP TO 4387 FT. THE FORECAST SOUNDING FROM THE LOCALLY RUN WRF ARW MODEL SHOWS NEAR EQUILIBRIUM OF WATER VAPOR CONCENTRATION IN THE AIR AT THE MORNING TEMPERATURE UP TO 2700 FEET. WE WILL KEEP THE FOG IN THE FORECAST FOR OVERNIGHT BUT AFTER 10 UTC AND IN THE FORM OF TEMPO GROUPS.

&&

.LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...GALE WARNING ENTIRE LAKE/NEARSHORE UNTIL 6PM CST THIS EVE. SMALL CRAFT ADVISORY IL AND IN WATERS 6PM TO MIDNIGHT TONITE.

&&

$$

.DISCUSSION... 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW OF PACIFIC AIR OVER THE CONUS BTWN TROFFING OVER THE W AND RDG OFF THE SE COAST. TEMPS OVER THE UPR GRT LKS REMAIN WELL ABV NORMAL WITH SW FLOW E OF SHRTWV/SFC-H85 TROFFING MOVING THRU THE UPR MS VALLEY. 00Z H85 TEMPS OVER THE UPR GRT LKS WERE 5-10C...BUT 00Z GRB/APX RAOBS INDICATE LYR BTWN H875-6 WAS QUITE DRY SO THAT H85 WBLB TEMP WAS NOT FAR FM 0C. DESPITE DRY AIR IN THE MID TROP AT THESE LOCATIONS...SOME PCPN AHEAD OF SHRTWV/TROFFING TO THE W WHERE 00Z DLH TAMDAR SDNG SHOW MID LVLS ARE MORE MOIST ALG AXIS OF SHARPER H8-7 FGEN IS MOVING TOWARD WRN LK SUP. MAINLY RA HAS FALLEN IN MN...BUT A FEW PLACES HAVE REPORTED SN WITH WBLB EFFECT LWRG TEMP PROFILE CLOSER TO 0C AS SHOWN ON MPX/DLH SDNGS. H3 WIND SPEEDS UP TO 140KT NOTED OVER UTAH IN ASSOCIATION WITH SHRTWV MOVING THRU WRN TROF.

MAIN FCST CONCERNS IN THE SHORT TERM ARE PCPN TRENDS THIS MRNG ASSOCIATED WITH SHRTWV NOW MOVING THRU THE UPR MS VALLEY...THEN PCPN CHCS AGAIN TNGT INTO SAT AS SHRTWV LIFTS OUT OF WRN TROF AND INTO THE CNTRL GRT LKS ON SAT. TIMING/IMPACT OF SHRTWV NOW IN THE GLFAK FCST CHALLENGE SAT NGT/SUN.

FOR TDAY...NAM/GFS SHOW SHRTWV RESPONSIBLE FOR PCPN IN MN SHEARING OUT TO THE NE AND INTO ONTARIO BY THIS AFTN. BOTH MODELS FAIRLY CONSISTENT INDICATING STRIPE OF GREATEST QPF WL IMPACT THE WRN CWA ALG AXIS OF SHARPER H8-7 FGEN CLOSE TO H85 TROF AXIS. LATEST RADAR TRENDS SUPPORT THIS FCST. IN FACT...THE 00Z NAM SHOWS 0.47 INCH WATER EQUIVALENT PCPN FALLING AT CMX BY 12Z. ALTHOUGH SFC TEMPS WOULD INDICATE RA...WBLB COOLING ALF UNDER BRIEFLY STRG FGEN/UVV SHOULD ALLOW A MIX WITH WET SNOW AS OBSVD UPSTREAM. WITH DRIER AIR ALF FARTHER E...EXPECT MAINLY JUST -DZ. EXPECT PCPN TO END SOON AFT 12Z...WHEN QVECTOR CNVGC/FGEN FCST TO EXIT TO THE NE. REST OF THE DAY LOOKS TO BE DRY IN THE WAKE OF SFC-H85 TROF DRIFTING ACRS THE AREA UNDER UPR CNVGC/H85-5 QVECTOR DVGC IN THE WAKE OF SHRTWV. DESPITE DRYING TREND ALF THIS MRNG...SUSPECT SC WL LINGER AS SUBSIDENCE INVRN DVLPS ABV LINGERING LLVL MSTR. AND THEN WHEN SOME DRIER LLVL AIR NOW IN THE PLAINS (SFC DWPTS IN THE 20S VS THE 30S IN PLACE NOW) LOOKS TO MOVE IN LATER IN THE DAY...MORE MID/HI CLD IN SW FLOW ALF IN ADVANCE OF SHRTWV LIFTING NEWD OUT OF THE WRN TROF SHOULD BE EXPANDING INTO THE FA. VARIOUS MOS GUIDANCE TEMPS SIMILAR SHOWING MAX TEMPS TDAY RANGING FM THE WELL ABV NORMAL UPR 30S OVER THE W TO NEAR 45 ACRS THE SCNTRL LOOK TO BE ON TRACK AS INCOMING AIRMASS IS OF PACIFIC ORIGIN. RECORD HI TEMP OF 36 TDAY AT THE MQT NWS WL FALL (TEMP AT MIDNGT ALREADY 36)...THE THIRD STRAIGHT DAY WITH A DAILY RECORD HI TEMP.

TNGT...H3 WIND MAX NOW OVER UTAH FCST TO MOVE TOWARD THE LOWER GRT LKS BY 12Z SAT...WITH H7-3 QVECTOR CNVGC/UPR DVGC IN THE LEFT EXIT OF THIS FEATURE IMPACTING THE FA OVERNGT BEFORE DEPARTING ON SAT MRNG. UPR DVGC/H85-5 QVECTOR CNVGC MUCH SHARPER OVER THE SE ZNS CLOSER TO DEPARTING SFC-H85 TROF/PACIFIC COLD FNT. GFS FCST SDNGS OVER THE SE ZNS SHOW SOME AIRMASS AT MNM-ISQ BECOMING RATHER MOIST THRU THE ENTIRE TROP ON THE NW EDGE OF SHARPER H8-7 FGEN...BUT DRIER AIR PERSISTING IN THE H7-9 LYR FM ERY-ESC A BIT FARTHER N AND W DEEPER INTO INCOMING MID LVL DRYING TDAY. WL CONTINUE WITH CHC POPS OVER THE SCNTRL AND E...BUT ELIMINATE PCPN CHCS FARTHER TO THE NW EXCEPT OVER THE KEWEENAW...WHERE GUIDANCE SUGS AIR SUFFICIENTLY COLD FOR SOME LES ARRIVING LATE. GIVEN DISTRIBUTION OF 00Z H85 TEMPS ON THU EVNG THAT SHOW H85 TEMPS BLO -10C CONFINED N OF LK WINNIPEG... PREFER THE WARMER NAM/UKMET FCST TEMPS (ARND -8C AT CMX BY 12Z SAT). SO...WL GO WITH ONLY A 30 POP FOR SCT -SHSN/FLURRIES THERE.

FOLLOWING DEPARTURE OF LEFT EXIT UPR DVGC/H7-3 QVECTOR CNVGC OVER THE E EARLY ON SAT...SFC-H85 RDG FCST TO SWEEP INTO THE UPR GRT LKS. EXCEPT FOR LO CHC POPS OVER THE KEWEENAW INTO THE AFTN WITH MARGINALLY COLD AIRMASS FOR LES AND OVER THE E EARLY BEFORE DEPARTURE OF LEFT EXIT DYNAMICS AND IN THE AFTN WITH ARRIVAL OF MARGINALLY COLD AIRMASS FOR LES...DAY SHOULD BE DRY ELSEWHERE EXCEPT FOR A FEW FLURRIES RELATED TO PASSAGE OF WEAK SHRTWV IN THE MRNG. WITH ARRIVAL OF H85 THERMAL TROF IN THE WAKE OF THIS WEAK SHRTWV... SAT WL BE COLDER THAN RECENT DAYS. BUT H85 TEMPS FCST BTWN -4C AND -8C STILL SUPPORT WELL ABV NORMAL TEMPS...ESPECIALLY WHERE THERE IS MORE SUNSHINE IN THE AFTN WITH ARRIVAL OF RDG AXIS/ACYC FLOW. PREFER HIER GFS FCST MOS TEMPS WITH INCOMING MARITIME POLAR PACIFIC AIRMASS.

PER NCEP PREFERENCE...HAVE TENDED TO FOLLOW A SOMEWHAT FARTHER N TRACK ON SAT NGT/SUN FOR SHRTWV/SFC LO SIMILAR TO THE 00Z UKMET (VS NAM/GFS FCST) REGARDING DISPOSITION OF SHRTWV NOW IN THE GLFAK. SINCE SFC LO TRACKS WELL TO THE N...FA MAY FALL INTO DRY SLOT ON SUN...BEST SHOWN BY 00Z UKMET. ON THE OTHER HAND...ECMWF/GFS SHOW FAIRLY SGNFT 12HR H5 HGT FALLS ACRS THE UPR GRT LKS (UP TO 100M) AND SHARP DPVA/H85-5 QVECTOR CNVGC. WL GO WITH HIEST CHC POPS OVER THE KEWEENAW...WHICH BE CLOSER TO DEEPER MSTR AND WHERE WLY FLOW ON SRN FLANK OF SFC LO MAY OFFER CHC FOR SOME LK ENHANCEMENT WITH H85 TEMPS AS LO AS -8C TO -10C.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...NONE. &&

$$ KC

.SYNOPSIS...DEPARTING UPPER LEVEL LOW PRESSURE WILL CAUSE A FEW LINGERING SHOWERS THIS MORNING. DEVELOPING OFFSHORE FLOW WILL BRING DRYING AND MOSTLY CLEAR SKIES THROUGH THE WEEKEND WITH LOCAL STRONG GUSTY WINDS AT TIMES...MAINLY THROUGH AND BELOW MOUNTAIN CANYONS AND PASSES. COOL TODAY THEN WARMER DAYS THROUGH EARLY NEXT WEEK. A STORM COULD BRING MORE CLOUDS...COOLING AND A CHANCE OF SHOWERS TOWARD THE END OF NEXT WEEK.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES...

.SHORT TERM (TODAY-SUNDAY)...VARIABLE CLOUDINESS AND ISOLATED SHOWERS CONTINUED THROUGH EARLY THIS MORNING. EARLY MORNING ACARS SOUNDINGS INDICATED STRONG WLY WINDS ALOFT. ONSHORE GRADIENTS TO THE E BUT TURNING OFFSHORE FROM THE N.

MOISTURE ROTATING AROUND THE W SIDE OF THE UPPER TROUGH WILL CONTINUE ISOLATED SHOWERS THIS MORNING. THE ATMOSPHERE WILL RAPIDLY DRY AS THE FLOW TURNS N TO NE DURING THE DAY TODAY. THERE WILL BE GOOD UPPER SUPPORT BUT ONLY MODERATE GRADIENT AND THERMAL SUPPORT FOR OFFSHORE WINDS. EXPECT THE STRONGEST WINDS TO BE IN THE SANTA ANA MOUNTAINS AND BELOW THE CAJON PASS LATE TONIGHT INTO SAT MORNING. THE WINDS WILL TAPER OFF SAT AFTERNOON THROUGH SUN BEFORE STARTING TO REDEVELOP SUN NIGHT. WILL GO WITH HIGH WIND WARNING FOR THE SAN BERNARDINO MOUNTAINS...INLAND EMPIRE AND SANTA ANA MOUNTAINS WITH WIND ADVISORY IN THE ORANGE COUNTY COASTAL AREAS...RIVERSIDE MOUNTAINS...SAN DIEGO MOUNTAINS AND SAN DIEGO INLAND VALLEYS THROUGH 6 PM SAT. ALSO WIND ADVISORY FOR THE DESERTS AND SAN DIEGO COASTAL AREAS FOR THE W TO NW WINDS EARLY TODAY. THE DRY OFFSHORE WINDS WILL INCREASE THE FIRE WEATHER HAZARD FOR A RED FLAG WARNING IN THE MOUNTAINS AND INLAND VALLEYS THROUGH MON AFTERNOON. COOL TODAY THEN WARMER SAT AND SUN...ESPECIALLY SUN W OF THE MOUNTAINS.

.LONG TERM (MONDAY-THURSDAY)...THE OFFSHORE FLOW WILL BRIEFLY REDEVELOP MON MORNING WITH LOCAL STRONG GUSTY WINDS THROUGH AND BELOW MOUNTAIN CANYONS AND PASSES ONCE AGAIN. OTHERWISE...HIGH PRESSURE ALOFT WILL KEEP SKIES MOSTLY CLEAR WITH A WARM DAY IN MOST AREAS MON. GRADUALLY COOLING INTO MID WEAK AS HEIGHT DECREASE AND OFFSHORE FLOW WEAKENS OR TURN BACK ONSHORE. ANOTHER UPPER TROUGH OF LOW PRESSURE SHOULD BRING MORE CLOUDS...COOLING AND A CHANCE OF SHOWERS NEXT THU.

&&

.AVIATION... UPPER TROUGH EXITING THE AREA THIS MORNING WITH SOME LINGERING SHOWERS/CIGS EXPECTED THROUGH 15Z...ESPECIALLY ON THE FOOTHILLS AND COASTAL SLOPES. THESE AREAS SHOULD CLEAR BY...OR SHORTLY AFTER 15Z AS A DRY N TO NE FLOW DEVELOPS ACROSS THE REGION. OTHERWISE MOSTLY CLEAR SKIES AND UNRESTRICTED VSBYS THROUGH TONIGHT.

STRONG AND GUSTY NW OF 25 TO 35 KNOTS NEAR MOUNTAIN TOP EARLY THIS MORNING WILL VEER TO THE NORTH...NORTH OF SAN DIEGO COUNTY BY 12Z... AND OVER THE REST OF THE AREA BY 15Z. STRONG WINDS IN EXCESS OF 35 KTS WILL CREATE AREAS OF SIGNIFICANT TURBULENCE AND WAVE/ROTOR ACTIVITY...ESPECIALLY SOUTH OF THE SAN BERNARDINOS. AFTER 15Z LOW LEVEL WINDS THROUGH AND BELOW CANYONS IN THE SANTA ANA MOUNTAINS AND BELOW THE CAJON PASS MAY EXCEED 50 KTS...CREATING DANGEROUS LOW LEVEL WIND SHEAR AND SEVERE TURBULENCE. THESE CONDITIONS ARE EXPECTED TO PERSIST THROUGH TONIGHT.

&&

.MARINE... A MODERATE WEST SWELL AND LARGE SHORT-PERIOD WIND WAVE...COMBINED WITH 25 TO 35 KT WINDS THIS MORNING WILL CREATE HAZARDOUS SMALL CRAFT CONDITIONS...SLOWLY SUBSIDING LATER THIS AFTERNOON. IN ADDITION...SURF OF 5 TO 7 FEET WITH LOCAL SETS TO 10 FEET WILL CREATE HAZARDOUS BEACH CONDITIONS WITH DANGEROUS RIP CURRENTS AND SOME LOCAL FLOODING OF LOW-LYING AREAS LATE THIS MORNING DURING HIGH TIDE. A HIGH SURF ADVISORY IS IN EFFECT.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...

HIGH WIND WARNING FOR THE SAN BERNARDINO MOUNTAINS...INLAND EMPIRE AND SANTA ANA MOUNTAINS THROUGH 6 PM SAT. SEE LAXNPWSGX.

WIND ADVISORY FOR THE DESERTS AND SAN DIEGO COASTAL AREAS UNTIL 2 PM TODAY. SEE LAXNPWSGX.

RED FLAG WARNING FOR THE MOUNTAINS AND INLAND VALLEYS LATE THIS MORNING THROUGH MONDAY AFTERNOON. SEE LAXRFWSGX.

HIGH SURF ADVISORY UNTIL 10 PM PST TONIGHT FOR ORANGE COUNTY AND SAN DIEGO COUNTY COASTS. SEE LAXCFWSGX.

GALE WARNING FOR THE OUTER WATERS UNTIL 8 AM AND SMALL CRAFT ADVISORIES FOR THE INNER AND OUTER WATERS THROUGH THIS AFTERNOON. SEE LAXCWFSGX.

&&

$$

PUBLIC...DVA AVIATION/MARINE...JAD

.DISCUSSION...

345 AM CST

S/WV INDICATED BY WATER VAPOR IMAGERY LIFTING RAPIDLY NE ACROSS WRN/NRN GRTLKS RGN EARLY THIS AM. THIS S/WV TO MOV QUICKLY AWAY FROM FCST AREA EARLY THIS MORNING...WITH DEEPER MOISTURE ALREADY TO THE EAST AND RADAR DETECTABLE PCPN ALREADY DEPARTED. GOES 11-3.9 MICRON IMAGERY INDICATES EXTENSIVE LOW STRATUS DECK LINGERING ALONG AND EAST OF SFC TROUGH AXIS ACROSS EASTERN IA...WITH SOME EROSION OF THESE LOWER CLOUDS INTO WESTERN IL. MODEL FCSTS OF OMEGA/DIV-Q FIELDS INDICATE BEST SUBSIDENCE IN WAKE OF DEPARTING WAVE OCCURRING NOW...SO AM NOT OVERLY OPTIMISTIC THAT MUCH CLRG OF LOW CLOUDS WILL OCCUR WITH MODEL TSECTS MAINTAINING SATURATED LAYER BELOW ABOUT 900 HPA AS LOW LEVEL TROF/FRONTAL BOUNDARY DRIFTS ACROSS FCST AREA TODAY. HGTS BEGIN TO FALL AGAIN THIS AFTN...AS NXT S/WV LIFTS OUT OF PLAINS AND CONTINUES AMPLIFICATION OF UPPER FLOW OVER NRN/CNTRL PLAINS WHICH WILL LIKELY HELP TO MAINTAIN OR REFORM CLOUD COVER IN MOIST LLVL AIR MASS. WILL MAINTAIN CHANCE POPS WITH SYSTEM TNGT/SAT MRNG...WITH HIGHEST PROBABILITY NWRN CWA ALONG TRACK OF STRONGLY SHEARED VORT MAX ALNG CYCLONIC SHEAR SIDE OF UPPER JET AXIS. FCST SNDGS/PARTIAL THICKNESS VALUES INDICATE RAIN MAIN PCPN TYPE...WITH POTENTIAL FOR MIX OF RA/SN INTO NWRN COUNTIES AROUND RFD TOWARD SUNRISE SAT. NOT LIKELY TO SEE ANY ACCUM HOWEVER WITH RELATIVELY WEAK FORCING AND WARM LLVLS. PCPN EXPECTED TO END BEFORE NOON SAT AS S/WV CONTINUES TO RACE OFF TO THE NORTHEAST.

WEAK SFC HIGH PRESSURE RDG BUILDS IN SAT AFTN WITH SIGNIFICANT DRYING IN LLVLS BEHIND COLD FRONT. THUS EXPCT SOME CLRG FROM WEST DURG AFTN. CLDS XPCTD TO RETURN BY SUN MRNG HOWEVER...AS NXT S/WV IN THIS VRY ACTIVE FLOW PATTERN DVLPS WAA/ISENTROPIC UPGLIDE INTO WRN GRTLKS. MAIN FORCING WITH SUNDAY SYSTEM MOVES NORTH...WITH NAM/GFS BOTH KEEPING PRECIP NORTH OF IL/WI BORDER.

TEMP WISE...STARTING OUT 15 DEG ABOVE NORMAL MAXES THIS MRNG...SO ANOTHER JANUARY DAY NEAR 50 DEG. BUMPED EARLY MRNG TEMPS UP BASED ON CURRENT TRENDS. OTHERWISE...GUIDANCE PRETTY SIMILAR NEXT FEW DAYS SO NO BIG DEVIATIONS.

SHOULD NOTE THAT WED NGT/THURS RAINFALL HAS LED TO SOME RISES ON AREA RIVERS. HAVE BEEN WORKING WITH NCRFC OVRNGT ON UPDATED CREST FORECASTS ON ILLINOIS AND LITTLE CALUMET RIVER BASINS. SEE KLOT FLOOD OUTLOOKS/WATCHES/WARNINGS FOR COMPLETE DETAILS.

RATZER

&&

.AVIATION DISCUSSION FOR 12Z TAFS...

600 AM CST

SURFACE TROUGH EXTENDING FROM NORTHEAST WISCONSIN INTO EASTERN IOWA WILL SLOWLY TRACK INTO NORTHWEST ILLINOIS THROUGH THE REMAINDER OF THE MORNING AND ACROSS NORTH CENTRAL AND NORTHEAST ILLINOIS THIS AFTERNOON INTO EARLY THIS EVENING. IFR/MVFR CIGS ARE BEING REPORTED ACROSS TERMINALS THIS MORNING WITH FAIRLY STRONG LOW LEVEL INVERSION BASED AROUND 3K FT PER REGIONAL ACARS SOUNDINGS THIS MORNING. DESPITE MID LEVEL DRYING OVERNIGHT...WILL LIKELY MAINTAIN LOW LEVEL SATURATION THROUGH THE DAY BASED ON PERSISTENCE OF THIS INVERSION AND A WEAKENING LOW LEVEL WIND FIELD IN ADVANCE OF THE LOW LEVEL TROUGH AXIS. IN ADDITION...MODEL TIME/HEIGHT SECTIONS INDICATE WEAK LIFT PERSISTING THROUGH THE AFTERNOON. WILL MAINTAIN POSSIBILITY OF SOME IFR CIGS THROUGH MID MORNING...WITH CIGS LIKELY REMAINING IN THE 1500-2000 FT RANGE THROUGH THE AFTERNOON GIVEN THE ABOVE FACTORS.

MORE SUBSTANTIAL FORCING FOR UPWARD VERTICAL MOTION SHOULD AFFECT TERMINALS TONIGHT AS NEXT UPPER SPEED MAX/UPPER LEVEL SHORT WAVE APPROACH THE REGION FROM THE PLAINS. HARD TO DISCOUNT POTENTIAL OF -RA OR -DZ AT ANY TIME AFT 23Z BUT TRIED TO TIME CHANCES OF -RA IN THE TAF COINCIDING WITH BEST UPPER LEVEL FORCING AROUND AND AFTER 06Z. WITH INCREASING LIFT THIS EVENING...HAVE TRENDED CIGS BACK DOWN TO LOWER END MVFR THIS EVENING...WITH IFR CIGS POSSIBLE IN ANY AREAS OF -RA/DZ. ALSO WILL CARRY MVFR VSBYS IN FOG THIS EVENING GIVEN LINGERING LOW LEVEL MOISTURE AND WEAK SFC FLOW IN THE VICINITY OF THE APPROACHING SFC TROUGH AXIS. MAY SEE BRIEF PERIOD OF NORTHEAST WINDS AOB 10 KTS AT ORD/MDW WITH THE SFC TROUGH PASSAGE THIS EVENING...BEFORE WINDS BECOME NORTHWEST AS SFC PRES GRADIENT STRENGTHENS OVERNIGHT.

MARSILI

&&

.LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...NONE.

&&

$$

.SHORT TERM...TONIGHT THROUGH SATURDAY SHOULD BRING A RETURN TO MORE SEASONABLE CONDITIONS. COLD FRONT MOVED THROUGH EARLY TODAY IS NOW WELL TO OUR EAST...BUT STRONG FRONTOGENETIC FORCING IS PRODUCING A BAND OF SNOW AND RAIN FROM IOWA INTO SOUTHWEST WISCONSIN AT MID AFTERNOON. THIS WILL TRANSLATE ACROSS THE SOUTHEAST HALF OF WISCONSIN TONIGHT AND SHOULD BE SUFFICIENT TO PRODUCE A BIT OF RAIN AND SNOW. BUFKIT FORECAST AND TAMDAR SOUNDINGS SUGGEST THE PRECIPITATION WILL BEGIN AS RAIN AND TURN TO SNOW. WHATEVER SNOW FALLS SHOULD MELT FAIRLY READILY AS WE HAVE HAD RECORD HIGH TEMPERATURES FOR THE PAST SEVERAL DAYS. SATURDAY WILL BE COOLER BUT YET ABOVE NORMAL WITH HIGHS IN THE 30S.

.LONG TERM...SATURDAY NITE THRU NEXT FRIDAY. FORECAST FOCUS ON PRECIPITATION CHANCES EARLY AND LATE IN THE WEEK.

THE MODELS ARE FAIRLY CONSISTENT EARLY ON AS A COLD FRONT MOVES THRU THE CWA SUNDAY...WITH A SECONDARY TROF ON MONDAY. ALTHOUGH THE MOISTURE WILL BE FAIRLY LIMITED THERE IS ENOUGH DYNAMICS TO CONTINUE THE CHANCY POPS ACROSS THE AREA AT THIS TIME. THE ETA AND GFS MOS NUMBERS ARE WITHIN REASON OF EACH OTHER SO WILL TAKE A BLEND OF BOTH FOR TEMPERATURES THRU SUNDAY...THEN SIDE WITH THE COLDER GFS SUNDAY NITE AS COLDER AIR FILTERS INTO THE REGION.

THE FLOW IS FAVORABLE FOR LES ACROSS PORTIONS OF NORTH CENTRAL WISCONSIN WITH NORTH NORTHWEST WINDS MONDAY NITE AND TUESDAY AS WINDS TURN WESTERLY WITH A RIDGE BUILDING IN LATE TUESDAY. THE RIDGE WILL CAUSE TEMPERATURES TO FALL A FEW MORE DEGREES WITH DRY WEATHER ACROSS THE CWA TUESDAY NITE.

DRY WEATHER WILL CONTINUE INTO WEDNESDAY NITE AS A LOW PRESSURE SYSTEM MOVING THRU SOUTHERN CANADA BRINGS A COLD FRONT THRU THE AREA THURSDAY AND THURSDAY NITE. THE AIR WILL BE COLD ENOUGH FOR ALL SNOW. WHILE THE ECMWF/DGEX INDICATE THE SYSTEM MOVING THRU A BIT QUICKER THE 12Z CANADIAN TAKES A MUCH SLOWER APPROACH. THE MREF/GFS SOLUTION IS SOMEWHERE IN BETWEEN...THEREFORE WILL SIDE WITH THIS SOLUTION AT THIS TIME.

NEXT FRIDAY BECOMES TRICKY AS THE 12Z GFS/00Z GEM LINGER THE FRONT AND ASSOCIATED PRECIP INTO FRIDAY WHILE THE 00Z AND 06Z GFS BUILD HIGH PRESSURE INTO THE REGION WITH COLDER TEMPERATURES AND DRY WEATHER. ALTHOUGH THE MREF DOES LINGER THE FRONT A BIT FARTHER NORTH ON FRIDAY... IT HOLDS OFF ON THE MAIN SURGE OF PRECIP UNTIL FRIDAY NITE. THEREFORE WILL KEEP FRIDAY DRY UNTIL NOW GIVEN THE UNCERTAINTY THAT FAR OUT. &&

.GRB WATCHES/WARNINGS/ADVISORIES... NONE &&

$$ KIECKBUSCH/ECKBERG WEATHER.GOV/GREENBAY

$$ RDM/KURIMSKI WEATHER.GOV/GREENBAY