Forecast Discussions mentioning "ACARS", "MDCRS", "AIRCRAFT", "TAMDAR", or "AMDAR" received at FSL on 02/05/07

.SYNOPSIS...HIGH PRESSURE ALOFT AND WEAK OFFSHORE FLOW WILL BRING FAIR AND WARMER WEATHER THROUGH EARLY NEXT WEEK WITH NEAR RECORD HIGH TEMPERATURES POSSIBLE SUNDAY AND MONDAY. LOCALLY WINDY THROUGH AND BELOW MOUNTAIN CANYONS AND PASSES AT TIMES. A SERIES OF LOW PRESSURE SYSTEMS WILL BRING MORE CLOUDS AND COOLING WITH CHANCES OF PRECIPITATION DURING THE LATTER PART OF NEXT WEEK.

&&

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

.SHORT TERM (TODAY-TUE)...CLEAR SKIES TODAY EXCEPT FOR PATCHY GROUND FOG INLAND THIS MORNING. ACARS SOUNDINGS SHOWED NE WINDS IN THE LOW LEVELS INCREASING TO ABOUT 20 KT AROUND 10 KFT WITH STRONG N WINDS ALOFT. OFFSHORE GRADIENTS WITH ABOUT -5 MB SAN-TPH.

A STRONG HIGH AMPLITUDE RIDGE OF HIGH PRESSURE ALONG THE W COAST WILL SLOWLY SHIFT INLAND SUN AND GRADUALLY WEAKEN MON AND TUE. OFFSHORE FLOW FROM THE N AND NE WILL SHIFT MORE OFFSHORE FROM THE E MON AND WEAKEN TUE. THERE COULD BE LOCAL GUSTY WINDS THROUGH AND BELOW MOUNTAIN CANYONS AND PASSES...BUT WIDESPREAD SUSTAINED ADVISORY STRENGTH WINDS ARE NOT EXPECTED. THE HIGH ALOFT AND OFFSHORE FLOW WILL BRING MUCH WARMER DAYS...ESPECIALLY SUN AND MON WHEN NEAR RECORD MAX TEMPS ARE POSSIBLE. A LITTLE COOLER TUE...MAINLY W OF THE MOUNTAINS. SKIES WILL BE MOSTLY CLEAR EXCEPT FOR A FEW HIGH CLOUDS AT TIMES. THE WARM...DRY OFFSHORE WINDS WILL ALSO INCREASE THE FIRE WEATHER HAZARD.

&&

.LONG TERM (WED-SAT)...HEIGHTS WILL CONTINUE TO LOWER WED AND ONSHORE FLOW WILL RETURN AS AN UPPER LEVEL TROUGH OF LOW PRESSURE APPROACHES FROM THE W. LOOKS LIKE A PATTERN IS SETTING UP FOR A STRONG SRN BRANCH OF FLOW ACROSS THE PAC BRINGING A SERIES OF SHORT WAVES THROUGH SRN CA. THE EXACT TIMING OF THESE FAST MOVING LOW LATITUDE SHORT WAVES IS STILL UNCERTAIN BUT THEY SHOULD EVENTUALLY BRING A CHANCE OF PRECIP. THE CURRENT TIMING INDICATES A WEAK SHORT WAVE WILL BRING A CHANCE OF SHOWERS LATE WED AND THU. SLIGHT CHANCE OF SHOWERS FRI IN MOIST WLY FLOW UNDER A VERY WEAK RIDGE. A STRONGER SYSTEMS COULD BRING MORE PRECIP NEXT WEEKEND.

&&

.AVIATION... WEAK OFFSHORE FLOW WILL BRING VFR CONDITIONS TO ALL AREA AIRPORTS THROUGH SUNDAY WITH A MOSTLY CLEAR SKY AND UNRESTRICTED VISIBILITIES.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...DVA AVIATION...HORTON

.SHORT TERM...BIGGEST CHALLENGE NEXT 24 HOURS WILL BE TEMPERATURE FCST. GUSTY AND ERRATIC CHINOOK WINDS WILL PLAY HAVOC WITH THE TEMPERATURE FIELD...ESPLY FM THE FOOTHILLS EASTWARD ACROSS THE I-25 URBAN CORRIDOR AND ADJACENT AREAS OF WELD...ERN ADAMS...ERN ARAPAHOE AND ELBERT COUNTIES. MODEL TEMPERATURE GUIDANCE INDICATING MAX TEMPERATURES TODAY IN THE 30S ALONG THE FRONT RANGE...BUT NO DOUBT WITH THE SPORADIC NATURE OF CHINOOK WINDS...MAY SEE A SPAN OF 10-15 DEGS WEST-TO-EAST ACROSS THE CORRIDOR. AT ANY EVENT...THE WARMUP IS UNDERWAY. 700 MB TEMP OF -12C NOW OVER DEN AS PER LOCAL ACARS OBS PROG BY WRF AND GFS TO WARM TO AROUND -4C BY 12Z/SUNDAY. WARMUP IN AND NEAR THE FRONT RANGE ALSO ATTRIBUTED TO STG AND GUSTY W-NWLY CHINOOK WINDS. WINDS NOT YET BLOWING AT LOWER ELEVATIONS...BUT OVER HIGHER ELEVATIONS OF THE FRONT RANGE WIND GUSTING IN THE 40-60 MPH IN THE PAST COUPLE HRS WITH A GUST TO 77 MPH PAST HOUR ATOP BERTHOUD PASS. SEVERE BLOWING AND DRIFTING SNOW HAS KEPT LOVELAND PASS CLOSED OVERNIGHT. AT THIS TIME BELIEVE WIDESPREAD WIND SPEEDS NOT EXPECTED TO REACH HIGH WIND CRITERIA BUT NO DOUBT SOME AREAS WILL SEE OCCASIONAL GUSTS MEETING THIS CRITERIA.

NEXT 24 HOURS COMBINATION OF STRONG NWLY FLOW ALOFT WITH NRN BRANCH OF THE POLAR JET IN THE AREA...INCREASING MTN TOP AND EAST SLOPE STATIC STABILITY WITH MID-LVL WAA...THE PRESENCE OF A DEEP LAYER MTN WAVE...AND A STEEP CROSS MTN PRESSURE GRADIENT ALL POINT TO A VERY WINDY PERIOD IN THE MTNS AND ADJACENT HIGH PLAINS. WILL EXTEND THE BLOWING SNOW ADVSY FOR MTN ZONES 33 AND 34 AND FTHL ZONES 35 AND 36 THROUGH 12Z/SUNDAY. WILL ALLOW THE SNOW AND BLOWING SNOW ADVSY FOR THE MTNS TO EXPIRE AT 12Z THIS MORNING AS ADDITIONAL SNOW ACCUMS SHOULD REMAIN LIGHT NEXT 24 HOURS. ACTUALLY BY TONIGHT...ANY SNOWFALL SHOULD BE CONFINED TO HIGHEST WEST FACING MTN SLOPES WITH THE ATMOSPHERE CONTINUING TO DRY AND STABILIZE.

LONG TERM...STRONG NORTHWEST FLOW ALOFT WITH CROSS MOUNTAIN COMPONENT 40-45 KNOTS AND MOUNTAIN TOP STABLE LAYER WILL CONTINUE TO BRING STRONG GUSTY WINDS TO THE FRONT RANGE SUNDAY MORNING. HOWEVER...WINDS ARE EXPECTED TO WEAKEN BY AFTERNOON AS MID LEVEL FLOW RELAXES TO AROUND 30 KNOTS. CANT RULE OUT LIGHT SNOW SHOWERS IN THE MOUNTAINS AS ANOTHER SURGE OF MID LEVEL MOISTURE PROGGED INTO THE AREA VIA DISSIPATING SHORT WAVE CAUGHT UP IN NORTHWEST FLOW ALOFT. OTHERWISE...TEMPERATURES WILL CONTINUE TO MODERATE WITH WARMING MID LEVEL TEMPERATURES AND DOWNSLOPE COMPONENT...ESPECIALLY NEAR THE FRONT RANGE WHERE EFFECTS OF SNOW COVER ARE MINIMIZED BY THE DOWNSLOPE.

EVEN MORE WARMING EXPECTED MONDAY AND TUESDAY AS MID LEVEL TEMPERATURES CONTINUE TO WARM. AT THIS TIME...DONT SEE ANY SURGE IN NORTHWEST FLOW ALOFT TO BE STRONG ENOUGH TO PUSH BACK AGAINST THE FRONT RANGE...SO WILL CONTINUE TREND OF WARMING THE FORECAST FOR THE I-25 URBAN CORRIDOR. EXPECT QUITE A FEW 50S BY MONDAY AND ESPECIALLY TUESDAY AS 700 MB TEMPS ARE PROGGED TO GET AS HIGH AS +6C BY TUESDAY AFTERNOON. COULDNT EVEN RULE OUT SOME LOWER 60S IF DOWNSLOPE COMPONENT IS STRONG ENOUGH. SPRING MUST BE COMING. FARTHER EAST ACROSS THE PLAINS...SNOW COVER WILL CONTINUE TO HAVE MORE IMPACT ON HIGH TEMPERATURES SO WILL HOLD FAST WITH A MORE CONSERVATIVE APPROACH TO DAYTIME HIGHS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...BLOWING SNOW ADVISORY TODAY AND TONIGHT FRONT RANGE MOUNTAINS AND FOOTHILLS...ZONES 33>36.

&&

$$

BAKER/BARJENBRUCH

.UPDATE... JUST UPDATED CWF TO ADD SCA FOR BISCAYNE BAY GIVEN REPORTS ACROSS THE AREA. SCA FOR THE COASTAL WATERS WILL LIKELY NEED TO BE EXTENDED FOR MONDAY BY MIDNIGHT SHIFT GIVEN TRENDS AND LATEST MODEL GUIDANCE.

.PREVIOUS UDATE FOLLOWS... LATEST SURFACE AND UPPER AIR DATA...INCLUDING ACARS...ANALYSIS SHOWS WEAK CONVERGENT BOUNDARY ACROSS SE BROWARD AND NORTHEAST MIAMI DADE AND THE ADJACENT COASTAL WATERS...THE RESULT OF LOW LEVEL SELY FLOW OVERRUNNING THE FRONTAL BNDRY TO THE SOUTH AND LOW LEVEL ENE FLOW DEPICTED BY RADAR AND MESO OBS RIGHT ALONG THE COAST. THIS CONVERGENT ACTIVITY WILL LIKELY CONTINUE ON AND OF NEXT COUPLE OF HOURS AND THEREFORE WILL MAINTAIN LKLY R FOR THE PERIOD IN THE FORECAST GIVEN ALSO THAT PRECIPITABLE WATER IS RUNNING AROUND 1.7 INCHES WHICH IS IN THE UPPER 20TH PERCENTILE OF THE MOISTURE CLIMATOLOGY FOR THIS TIME OF THE YEAR. THIS MERGES FINE WITH REST OF FORECAST WHICH CALLS FOR LKLY LIGHT RAIN ACROSS SOUTH FLORIDA THIS EVENING BECOMING A CHC OVERNIGHT OF LIGHT RAIN.

WINDS ACROSS THE AREA HAVE BEEN ON THE INCREASE WITH SETTLEMENT POINT SHOWING SUSTAINED 20 TO 25 KNOTS FOR HOURS NOW AND LAKE WORTH HAS BEEN SHOWING SUSTAINED 20 KNOTS FOR SEVERAL HOURS AND IS NOW IN THE 20 TO 25 KNOTS RANGE. BREEZE CONDITIONS ARE ALSO BEING REFLECTED ACROSS COASTAL AREAS WITH WINDS SLIGHTLY BELOW THAT INLAND BUT STILL IN THE 10 TO 15 MPH RANGE.

ALL IN ALL...CURRENT FORECAST LOOKS THEN ON TRACK.

PS

&&

.PREV DISCUSSION... /ISSUED 307 PM EST SUN FEB 4 2007/

DISCUSSION... STRONGER NORTHERLY WINDS ARE FINALLY BEGINNING TO SPREAD ACROSS THE AREA THIS AFTERNOON...WITH RESIDUAL COASTAL SURFACE TROUGH NOW BEGINNING TO SHIFT EASTWARD OFF THE ATLANTIC COAST. JUST ABOVE THE SURFACE...A WEAK BUT SIGNIFICANT CONFLUENCE OF WIND IN THE 925-850 MB LAYER HAS RESULTED IN SUFFICIENT FORCING WITHIN VERY MOIST AIRMASS TO RESULT IN BROKEN/OVERCAST STRATUS AND SCATTERED LIGHT SHOWERS THIS AFTERNOON. MODELS SUGGEST THAT THIS ZONE OF ELEVATED CONVERGENCE WILL SHIFT NORTHWARD THROUGH THE NIGHT...AS VERY STRONG NORTHERLY WINDS SPREAD SOUTHWARD AT THE SURFACE. RESULTING WARM ADVECTION REGIME WILL LIKELY KEEP GREATEST CONCENTRATION OF SHOWERS ACROSS THE NORTHERN HALF OF THE AREA OVERNIGHT...WITH NORTHEAST WINDS ALSO RESULTING IN SCATTERED SHOWERS IN FAVORED AREAS ALONG THE ATLANTIC COAST. THIS PATTERN IS EXPECTED TO PERSIST THROUGHOUT MONDAY AND TUESDAY...WITH THE AXIS OF ELEVATED CONVERGENCE REMAINING NEARLY STATIONARY ACROSS THE NORTHERN COUNTIES. THUS...WILL KEEP HIGHEST POPS ACROSS THE NORTH AND ALONG THE ATLANTIC COAST...WITH NORTHEAST FLOW REGIME REMAINING STRONG THROUGH THIS PERIOD. HOWEVER...MOS POP GUIDANCE IS LIKELY MUCH TOO HIGH GIVEN ANTICIPATED COVERAGE...AND HAVE UNDERCUT THESE VALUES. CONCERNING TEMPERATURES...A VERY SMALL DIURNAL TREND IS EXPECTED... GIVEN PRESENCE OF THICK CLOUD COVER...SCATTERED SHOWERS AND MODEST COLD ADVECTION.

IN THE EXTENDED FORECAST...A STRONGER AND DEEPER SURGE OF COLD AIR WILL LIKELY ARRIVE IN SOUTH FLORIDA ON WEDNESDAY MORNING... BRINGING AN END TO SIGNIFICANT PRECIPITATION CHANCES AND ALLOWING SKIES TO GRADUALLY CLEAR FROM THE NORTH. THE LATEST RUN OF THE GFS IS NOW SUGGESTING THE DEVELOPMENT OF A SURFACE LOW OVER THE GULF OF MEXICO...WITH THIS FEATURE EXPECTED TO TRACK ACROSS THE FORECAST AREA ON THURSDAY. GIVEN THAT THIS IS THE FIRST TIME THE GFS HAS OFFERED THIS SOLUTION...AND THE UKMET/ECMWF/CMC SOLUTIONS ARE NOT INDICATING OF THIS SORT...WILL HOLD POPS AT SLIGHT CHANCE FOR NOW AND LET FUTURE SHIFTS REEVALUATE. OTHERWISE...MAXIMUM TEMPERATURES WILL SLOWLY WARM BACK INTO THE MID AND UPPER 70S BY THE MIDDLE OF THE WEEK...AND SHOULD REMAIN IN THIS RANGE UNTIL ANOTHER WEAK FRONTAL PASSAGE NEXT WEEKEND. HOWEVER...BEYOND THURSDAY...WILL FORECAST NO SIGNIFICANT CHANCES FOR PRECIPITATION THROUGH NEXT SUNDAY.

AVIATION... MVFR CEILINGS AND VISIBILITIES ARE EXPECTED TO CONTINUE THROUGH THIS EVENING AT ALL OF THE TAF SITES IN THE CWA...WITH A FEW OF THE EAST COAST TAF SITES SEEING IFR CONDITIONS IN THE CEILINGS AT TIMES. THE LIGHT TO MODERATE SHOWERS WILL ALSO CONTINUE OVER ALL OF THE TAF SITES THROUGH THE EVENING HOURS.

AFTER 23Z...THE WINDS WILL START TO PICK UP FROM THE NORTHWEST AND BE AT THE BREEZY CONDITIONS AFTER 6Z TONIGHT OVER ALL OF THE TAF SITES IN THE CWA. THIS WILL BRING AND END TO THE IFR CONDITIONS...BUT WILL REMAIN IN THE MVFR CONDITIONS WITH VCSH OF SHOWERS.

MARINE... NORTHERLY TO NORTHEASTERLY FLOW IS FINALLY BEGINNING TO INCREASE ACROSS THE MARINE ZONES...AND SHOULD REMAIN VERY STRONG /20-25 KNOTS/ THROUGH TUESDAY MORNING. THUS...WILL KEEP SMALL CRAFT ADVISORIES IN PLACE AND EXTEND THROUGH 12Z MONDAY WITH THIS ISSUANCE. WINDS WILL VEER TO THE EAST AND WEAKEN ON TUESDAY...WITH AN INCREASING THREAT FOR RIP CURRENTS ALONG THE ATLANTIC COAST. OTHERWISE...LATEST WAVE WATCH GUIDANCE IS ADVERTISING WEAK NORTHERLY LONG PERIOD SWELLS AFFECTING THE ATLANTIC COAST ON MONDAY AND EARLY TUESDAY...BUT HAS BACKED OFF ON THE SWELL EVENT FOR MID-WEEK.

FIRE WEATHER... NO SIGNIFICANT PROBLEMS ARE ANTICIPATED THROUGHOUT THIS FORECAST PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 61 69 57 70 / 60 40 40 30 FORT LAUDERDALE 63 71 60 71 / 60 40 40 30 MIAMI 62 71 59 72 / 60 30 30 20 NAPLES 52 68 49 72 / 60 40 40 30

&&

.MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR AMZ650-AMZ651- AMZ670-AMZ671.

GM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR GMZ676.

&&

$$

LONG TERM...52 SHORT TERM...04

.UPDATE... LATEST SURFACE AND UPPER AIR DATA...INCLUDING ACARS...ANALYSIS SHOWS WEAK CONVERGENT BOUNDARY ACROSS SE BROWARD AND NORTHEAST MIAMI DADE AND THE ADJACENT COASTAL WATERS...THE RESULT OF LOW LEVEL SELY FLOW OVERRUNNING THE FRONTAL BNDRY TO THE SOUTH AND LOW LEVEL ENE FLOW DEPICTED BY RADAR AND MESO OBS RIGHT ALONG THE COAST. THIS CONVERGENT ACTIVITY WILL LIKELY CONTINUE ON AND OF NEXT COUPLE OF HOURS AND THEREFORE WILL MAINTAIN LKLY R FOR THE PERIOD IN THE FORECAST GIVEN ALSO THAT PRECIPITABLE WATER IS RUNNING AROUND 1.7 INCHES WHICH IS IN THE UPPER 20TH PERCENTILE OF THE MOISTURE CLIMATOLOGY FOR THIS TIME OF THE YEAR. THIS MERGES FINE WITH REST OF FORECAST WHICH CALLS FOR LKLY LIGHT RAIN ACROSS SOUTH FLORIDA THIS EVENING BECOMING A CHC OVERNIGHT OF LIGHT RAIN.

WINDS ACROSS THE AREA HAVE BEEN ON THE INCREASE WITH SETTLEMENT POINT SHOWING SUSTAINED 20 TO 25 KNOTS FOR HOURS NOW AND LAKE WORTH HAS BEEN SHOWING SUSTAINED 20 KNOTS FOR SEVERAL HOURS AND IS NOW IN THE 20 TO 25 KNOTS RANGE. BREEZE CONDITIONS ARE ALSO BEING REFLECTED ACROSS COASTAL AREAS WITH WINDS SLIGHTLY BELOW THAT INLAND BUT STILL IN THE 10 TO 15 MPH RANGE.

ALL IN ALL...CURRENT FORECAST LOOKS THEN ON TRACK.

PS

&&

.PREV DISCUSSION... /ISSUED 307 PM EST SUN FEB 4 2007/

DISCUSSION... STRONGER NORTHERLY WINDS ARE FINALLY BEGINNING TO SPREAD ACROSS THE AREA THIS AFTERNOON...WITH RESIDUAL COASTAL SURFACE TROUGH NOW BEGINNING TO SHIFT EASTWARD OFF THE ATLANTIC COAST. JUST ABOVE THE SURFACE...A WEAK BUT SIGNIFICANT CONFLUENCE OF WIND IN THE 925-850 MB LAYER HAS RESULTED IN SUFFICIENT FORCING WITHIN VERY MOIST AIRMASS TO RESULT IN BROKEN/OVERCAST STRATUS AND SCATTERED LIGHT SHOWERS THIS AFTERNOON. MODELS SUGGEST THAT THIS ZONE OF ELEVATED CONVERGENCE WILL SHIFT NORTHWARD THROUGH THE NIGHT...AS VERY STRONG NORTHERLY WINDS SPREAD SOUTHWARD AT THE SURFACE. RESULTING WARM ADVECTION REGIME WILL LIKELY KEEP GREATEST CONCENTRATION OF SHOWERS ACROSS THE NORTHERN HALF OF THE AREA OVERNIGHT...WITH NORTHEAST WINDS ALSO RESULTING IN SCATTERED SHOWERS IN FAVORED AREAS ALONG THE ATLANTIC COAST. THIS PATTERN IS EXPECTED TO PERSIST THROUGHOUT MONDAY AND TUESDAY...WITH THE AXIS OF ELEVATED CONVERGENCE REMAINING NEARLY STATIONARY ACROSS THE NORTHERN COUNTIES. THUS...WILL KEEP HIGHEST POPS ACROSS THE NORTH AND ALONG THE ATLANTIC COAST...WITH NORTHEAST FLOW REGIME REMAINING STRONG THROUGH THIS PERIOD. HOWEVER...MOS POP GUIDANCE IS LIKELY MUCH TOO HIGH GIVEN ANTICIPATED COVERAGE...AND HAVE UNDERCUT THESE VALUES. CONCERNING TEMPERATURES...A VERY SMALL DIURNAL TREND IS EXPECTED... GIVEN PRESENCE OF THICK CLOUD COVER...SCATTERED SHOWERS AND MODEST COLD ADVECTION.

IN THE EXTENDED FORECAST...A STRONGER AND DEEPER SURGE OF COLD AIR WILL LIKELY ARRIVE IN SOUTH FLORIDA ON WEDNESDAY MORNING... BRINGING AN END TO SIGNIFICANT PRECIPITATION CHANCES AND ALLOWING SKIES TO GRADUALLY CLEAR FROM THE NORTH. THE LATEST RUN OF THE GFS IS NOW SUGGESTING THE DEVELOPMENT OF A SURFACE LOW OVER THE GULF OF MEXICO...WITH THIS FEATURE EXPECTED TO TRACK ACROSS THE FORECAST AREA ON THURSDAY. GIVEN THAT THIS IS THE FIRST TIME THE GFS HAS OFFERED THIS SOLUTION...AND THE UKMET/ECMWF/CMC SOLUTIONS ARE NOT INDICATING OF THIS SORT...WILL HOLD POPS AT SLIGHT CHANCE FOR NOW AND LET FUTURE SHIFTS REEVALUATE. OTHERWISE...MAXIMUM TEMPERATURES WILL SLOWLY WARM BACK INTO THE MID AND UPPER 70S BY THE MIDDLE OF THE WEEK...AND SHOULD REMAIN IN THIS RANGE UNTIL ANOTHER WEAK FRONTAL PASSAGE NEXT WEEKEND. HOWEVER...BEYOND THURSDAY...WILL FORECAST NO SIGNIFICANT CHANCES FOR PRECIPITATION THROUGH NEXT SUNDAY.

AVIATION... MVFR CEILINGS AND VISIBILITIES ARE EXPECTED TO CONTINUE THROUGH THIS EVENING AT ALL OF THE TAF SITES IN THE CWA...WITH A FEW OF THE EAST COAST TAF SITES SEEING IFR CONDITIONS IN THE CEILINGS AT TIMES. THE LIGHT TO MODERATE SHOWERS WILL ALSO CONTINUE OVER ALL OF THE TAF SITES THROUGH THE EVENING HOURS.

AFTER 23Z...THE WINDS WILL START TO PICK UP FROM THE NORTHWEST AND BE AT THE BREEZY CONDITIONS AFTER 6Z TONIGHT OVER ALL OF THE TAF SITES IN THE CWA. THIS WILL BRING AND END TO THE IFR CONDITIONS...BUT WILL REMAIN IN THE MVFR CONDITIONS WITH VCSH OF SHOWERS.

MARINE... NORTHERLY TO NORTHEASTERLY FLOW IS FINALLY BEGINNING TO INCREASE ACROSS THE MARINE ZONES...AND SHOULD REMAIN VERY STRONG /20-25 KNOTS/ THROUGH TUESDAY MORNING. THUS...WILL KEEP SMALL CRAFT ADVISORIES IN PLACE AND EXTEND THROUGH 12Z MONDAY WITH THIS ISSUANCE. WINDS WILL VEER TO THE EAST AND WEAKEN ON TUESDAY...WITH AN INCREASING THREAT FOR RIP CURRENTS ALONG THE ATLANTIC COAST. OTHERWISE...LATEST WAVE WATCH GUIDANCE IS ADVERTISING WEAK NORTHERLY LONG PERIOD SWELLS AFFECTING THE ATLANTIC COAST ON MONDAY AND EARLY TUESDAY...BUT HAS BACKED OFF ON THE SWELL EVENT FOR MID-WEEK.

FIRE WEATHER... NO SIGNIFICANT PROBLEMS ARE ANTICIPATED THROUGHOUT THIS FORECAST PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 61 69 57 70 / 60 40 40 30 FORT LAUDERDALE 63 71 60 71 / 60 40 40 30 MIAMI 62 71 59 72 / 60 30 30 20 NAPLES 52 68 49 72 / 60 40 40 30

&&

.MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR AMZ650-AMZ651- AMZ670-AMZ671.

GM...SMALL CRAFT ADVISORY UNTIL 7 AM EST MONDAY FOR GMZ676.

&&

$$

LONG TERM...52 SHORT TERM...04

.SHORT TERM (TODAY AND TONIGHT)... WATER VAPOR LOOP SHOWS A LARGE TROUGH DOMINATES CENTRAL CANADA AND NORTH CENTRAL CONUS...WITH A SHORT WAVE PRESSING INTO NEW ENGLAND...AS THE NEXT WAVE ROTATES INTO THE MIDWEST. ACARS 400-250MB WIND OBSERVATIONS REVEAL A 175-220KT SOUTHWESTERLY JET EXTENDS FROM THE PLAINS THROUGH THE MID ATLANTIC. 04Z SURFACE ANALYSIS PLACED A COLD FRONT FROM A 991MB OCCLUDED CYCLONE IN WESTERN QUEBEC SOUTH THROUGH THE MID ATLANTIC. A TROUGH WAS NOTED IN THE LEE OF THE APPALACHIANS WITH A 1026MB ANTICYCLONE ACROSS EASTERN TEXAS. THE NEXT COLD FRONT WAS SLICING THROUGH THE UPPER MIDWEST.

UPSLOPE SNOW SHOWERS ARE QUICKLY DECAYING EARLY THIS MORNING AS ANTICYCLONIC FLOW BUILDS IN FROM THE OHIO VALLEY. A FEW AREAS OF FLURRIES EAST TO THE WESTERN WASHINGTON SUBURBS WILL BE VERY SHORT LIVED.

COLD/DRY ADVECTION ALONG WITH DECENT DOWNSLOPE COMPONENT WILL CONTINUE TO ERODE LOW LEVEL MOISTURE AND PROVIDE A SUNNY DAY EAST OF THE MOUNTAINS. GRADIENT BEHIND THE LAST COLD FRONT WILL STILL SUPPORT WIND GUSTS AS MIXING DEEPENS DURING THE AFTERNOON. WENT BELOW MOS GUIDANCE FOR HIGH TEMPERATURES BASED ON RECENT PERFORMANCE AND COLD ADVECTION.

ANOTHER COLD FRONT PRESSES THROUGH FROM THE OHIO VALLEY THIS EVENING...SHARPENING THE GRADIENT AND REINVIGORATING COLD ADVECTION. WIND GUSTS MAY BE AS HIGH AS 40 MPH IN THE HIGHER TERRAIN...PROMPTING A WIND CHILL ADVISORY ACROSS MUCH OF THE WEST VIRGINIA AND MARYLAND PAN HANDLE REGION. WIND CHILLS DIP INTO THE SINGLE DIGITS EAST TO THE CHESAPEAKE BAY.

PASSAGE OF THE NEXT SHORT WAVE INTO THE EASTERN GREAT LAKES THIS EVENING IS EXPECTED TO BRING SCATTERED CLOUDS TRAPPED UNDER THE SUBSIDENCE INVERSION AND TO RE-INITIATE UPSLOPE SNOW SHOWERS IN THE MOUNTAINS.

&&

.AVIATION... DOWNSLOPE FLOW HAS SCOURED OUT MOISTURE EAST OF THE MOUNTAINS. WINDS WILL REMAIN GUSTY THROUGH THE TAF CYCLE...BACKING THIS EVENING AHEAD OF THE NEXT COLD FRONT...AND VEERING OVERNIGHT AS THE FRONTAL BOUNDARY PUSHES THROUGH. THERE COULD BE SOME MOISTURE TRAPPED UNDER THE SUBSIDENCE INVERSION THIS EVENING AS THE NEXT WAVE MOVES ACROSS THE EASTERN GREAT LAKES.

&&

.MARINE... SMALL CRAFT ADVISORY IS IN EFFECT.

00Z ETA/GFS MOS AT THOMAS POINT INDICATES SUSTAINED WINDS WILL INCREASE FROM 15KT TO 20KT BEGINNING THIS AFTERNOON. 00Z PROXIMITY NAM/GFS BUFKIT FORECAST SOUNDINGS INDICATE WIND GUST POTENTIAL OF 25KT THIS AFTERNOON...AND UP TO 30KT FOR A PERIOD TONIGHT.

SCA WINDS WILL CONTINUE THROUGH SUN AFTERNOON FOR THE MARINE WATERS UNDER STRONG CAA.

A BRIEF RESPITE IN SCA WINDS IS LIKELY SUN NGT AND MON...BUT EXPECT RENEWED SCA WINDS LATE MON THROUGH MIDWEEK AS CAA ENSUES.

&&

.TIDES... WATER LEVELS ARE CURRENTLY A HALF FOOT TO A FOOT ABOVE ASTRONOMICAL PREDICTIONS. THE LUNAR CYCLE IS AT FULL MOON (99% FULL).

THE CHESAPEAKE BAY OPERATIONAL FORECAST SYSTEM WHICH HAD A GOOD HANDLE ON OBSERVED DEPARTURES INDICATES DEPARTURES WILL DIMINISH THROUGH THE AFTERNOON...BUT STILL REMAIN A BIT ABOVE ASTRONOMICAL PREDICTIONS. THE NOAA EXTRATROPICAL SURGE MODEL DID NOT CAPTURE OBSERVED DEPARTURES.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY...

COLDEST AIRMASS OVERHEAD SUNDAY THROUGH MONDAY NGT ACROSS OUR AREA. HAVE UNDERCUT MOS FCST BETWEEN 1-2 CATEGORIES DURING THAT TIMEFRAME BASED ON THE SNOWPACK OUT WEST AND THE FACT THAT CLIMO PROBABLY HOLDING MOS PREDICTIONS BACK FROM THE REALISTIC COLDER VALUES. WILL ALSO CONTINUE TO MENTION HIGH CHCS FOR SN SHWRS ALONG AND W OF THE ALLEG FRONT DURING SUNDAY THROUGH MON NGT WITH GOOD WIND TRAJECTORIES AND DELTA T VALUES.

SLIGHT MODERATION IN TEMPS BUT STILL BELOW NORMS TUE-WED. 00Z GFS IS BRINGING A CLIPPER ESE INTO THE MID ATLC LATE WED INTO THU AND SQUEEZING OUT ALMOST 0.10 INCH QPF WITH THIS SYSTEM ACROSS MUCH OF OUR AREA. WILL INTRODUCE LOW CHC (20-30 POP) ACROSS THE NW HALF OF THE CWFA WITH THIS SYSTEM. 00Z MEX POPS AROUND 50 DURING THIS PERIOD AT MOST SITES. MEDIUM RANGE ENSEMBLES NOT AS GUNG HO ON THE PTNL FOR QPF WITH THIS FEATURE...PARTIALLY BECAUSE YOU GET A 0.10 INCH POP FORECAST VERSUS THE 0.01 INCH WITH THE MEX MOS. 00Z ECMWF IS FASTER WITH THIS FEATURE AND SEEMS TO BE AS STRONG AS THE 00Z GFS RUN. SREF PLUME CHARTS SHOWING AN UPSWING IN SNOW CHCS IN EASTERN OHIO ON THE 7TH IN CONJUNCTION WITH THE CLIPPER SO AN EXTRAPOLATION TO THE 8TH WOULD SUPPORT A CHC OF SNOW AT LEAST IN OUR NW ZONES.

WHETHER OR NOT WE END UP GETTING ANY SNOW WITH THIS NEXT FEATURE IS DEBATABLE...HWVR IT SEEMS LIKELY A REINFORCING SHOT OF ARCTIC AIR WILL ONCE AGAIN BUILD ACROSS OUR REGION WED-THU WITH TEMPS REMAINING BELOW NORMAL THROUGH THE END OF THE WORK WEEK.

&&

.LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 12 PM EST SUNDAY FOR MDZ003-501-502.

VA...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 12 PM EST SUNDAY FOR VAZ021.

WV...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 12 PM EST SUNDAY FOR WVZ050-051-054-055-501>504.

MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR ANZ530>537.

&&

$$

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

.SHORT TERM /REST OF TODAY/... DRY HIGH PRESSURE RIDGING UP FROM THE DEEP SOUTH WILL REMAIN IN PLACE TODAY...BUT WITH A WEAK LEE TROUGH EAST OF MTNS. THE SFC RIDGE WILL GET SUPPRESSED SOUTH BY LATE DAY AS A COLD FRONT MOVES THROUGH THE OHIO VALLEY THIS AFTERNOON UNDER THE BROAD AND DEEP UPPER TROUGH. BREEZY TO WINDY CONDITIONS ARE ANTICIPATED THROUGH THE AFTERNOON...WITH 850 MB FLOW REACHING 35 TO 40 KT ACROSS THE NRN TIER LATE ALONG WITH WEAK COLD ADVECTION. WILL LEAVE THE CURRENT LAKE WIND ADVISORY IN PLACE. THE ONLY CLOUDS TO SPEAK OF THIS AFTERNOON WILL BE SCATTERED UPSLOPE INDUCED CLOUDS IN THE WRN MTNS AND SCATTERED CIRRUS UNDER THE PIEDMONT JET AXIS. WILL TRIM TEMPERATURES A DEGREE OR SO GIVEN A SLOW START NEXT TO GUIDANCE AND VERY COOL THICKNESSES ON THE MORNING SOUNDINGS.

&&

.FIRE WEATHER... COORDINATION WITH FIRE WEATHER USERS TODAY AND YESTERDAY HAS INDICATED THAT RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET DUE TO WET FUELS. HOWEVER...LOW RH AND BREEZY/WINDY CONDITIONS WILL LEAD TO RAPID FUEL DRYING THROUGH MONDAY. A FIRE DANGER STATEMENT FOR NORTH CAROLINA COULD BE NEEDED AT SOME POINT THIS WEEKEND...HOWEVER WILL JUST HEADLINE WIND/RH CONCERNS FOR NOW.

&&

.PREV DISCUSSION... /ISSUED 221 AM EST SAT FEB 3 2007/

SHORT TERM /TODAY THROUGH MONDAY/... EXPECT A FEW FLURRIES THIS MORNING ACROSS THE NORTHERN MOUNTAINS OF NORTH CAROLINA. AIRMASS DRIES OUT THIS AFTERNOON TO THE POINT WHERE FLURRIES SHOULD END. WINDY CONDITIONS WILL PREVAIL ACROSS THE NC MOUNTAINS...AND A LAKE WIND ADVISORY WILL BE NEEDED THERE. I/M JUST GOING BREEZY FOR NOW ACROSS THE UPSTATE AND NE GA...BUT DEPENDING ON THE DEPTH OF THE MIXING...A FEW HOURS OF WINDY CONDITIONS ARE QUITE POSSIBLE IN THESE AREAS BY MID AFTERNOON.

LATE TONIGHT A WEAKENING SHORT WAVE WILL APPROACH THE NC MOUNTAINS. 1000-500MB LAYER RH/S INCREASE TO OVER 70 PERCENT ALONG THE TN LINE BETWEEN 9 AND 12 UTC. WHILE THE LOW LEVEL FLOW IS OUT OF THE WEST...WHICH IS NOT OPTIMAL FOR UPSLOPE SNOW SHOWERS...THE WINDS ARE FAIRLY STRONG AT 30 TO 40 KTS. WITH H8 TEMPS AROUND -10 DEG C...THIS SHOULD BE ADEQUATE FOR SNOW SHOWERS FROM MADISON CO NORTHWARD. WENT ON THE COOL SIDE OF MOS TODAY AND TONIGHT.

SNOW SHOWERS WILL LINGER ALONG THE TENN BORDER SUN MORNING...BUT MOISTURE IS EXPECTED TO DIMINISH BY EARLY PM. THIS WILL GIVE WAY TO A DRY BUT SEASONABLY COOL END TO THE WEEKEND.

A STRONG SW TROUGH DIVING OUT OF THE UPPER MIDWEST WILL DEEPEN THE EASTERN TROUGH EARLY NEXT WEEK...SENDING A REINFORCING SHOT OF COLD AIR INTO THE REGION BY EARLY MONDAY. AS A RESULT...MONDAY/S MAX TEMPS WILL LIKELY RANGE FROM THE LOW TEENS IN THE HIGHER ELEVATIONS...TO THE MID AND UPPER 20S IN THE VALLEYS...TO THE MID AND UPPER 30S ACROSS MOST OF THE PIEDMONT.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... EASTERN LONG WAVE TROUGH WILL CONTINUE TO DOMINATE THE WEATHER THROUGH AT LEAST MID-WEEK. THIS WILL RESULT IN A MOSTLY DRY FORECAST THROUGH THE PERIOD. THE MAIN STORY WILL BE THE COLD...AS TEMPS SHOULD REMAIN BELOW...EVEN WELL BELOW NORMAL THROUGH MID-WEEK... WHEN THE LARGE SCALE FLOW WILL TAKE ON A MORE ZONAL CONFIGURATION ACROSS THE EASTERN STATES. HOWEVER...ANOTHER STRONG SW TROUGH DIVING OUT OF THE UPPER MIDWEST WILL LIKELY SEND ANOTHER SHOT OF COLD AIR INTO THE REGION LATE NEXT WEEK.

AVIATION /07Z-06Z/... WITH A MUCH DRIER AIRMASS WORKING INTO THE REGION...AND WITH MANY TAF SITES REMAINING MIXED THROUGH SUNRISE...DON/T SEE ANY FOG OR STRATUS CONCERNS THIS MORNING. WINDS WILL GRADUALLY INCREASE INTO THE EARLY AFTERNOON HOURS OUT OF THE WSW. THERE WILL BE DEEP MIXING THIS AFTERNOON...AND GUSTS INTO THE MID 20KT RANGE ARE POSSIBLE JUST ABOUT ANYWHERE...BUT ESPECIALLY ACROSS THE UPSTATE. AT KAVL WINDS WILL BE MORE NORTHWESTERLY...BUT AS MIXING DEEPENS DURING THE AFTERNOON HOURS...WOULDN/T BE SURPRISED TO SEE THEM TURN OUT OF THE WEST AT TIMES. THIS WILL MAKE FOR QUITE A BIT OF LOW LEVEL TURBULENCE...SOMETHING SMALLER AIRCRAFT WILL NEED TO BE WARY OF.

FIRE WEATHER... DEWPOINTS SHOULD MIX OUT INTO THE SINGLE DIGITS IN THE NORTH CAROLINA ZONES THIS AFTERNOON. WITH A WESTERLY DOWNSLOPE FLOW...DEWPOINTS COULD BECOME ESPECIALLY LOW ACROSS THE FRENCH BROAD VALLEY AND THE NC FOOTHILLS...WITH RH/S FALLING WELL INTO THE TEENS BY LATE AFTERNOON. ELSEWHERE...RH/S WILL STILL FALL AT LEAST INTO THE L-M20S. SO...ACROSS THE MOUNTAINS...THE UPSTATE AND NE GA THERE IS A GOOD CHANCE OF MEETING METEOROLOGICAL RED FLAG CRITERIA. HOWEVER...CALLS TO LAND MANAGEMENT AGENCIES YESTERDAY REVEALED THAT FUEL MOISTURE IS VERY HIGH...SO THE FIRE DANGER IS NOT HIGH ENOUGH TO WARRANT A RED FLAG WARNING.

&&

.GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...LAKE WIND ADVISORY UNTIL 6 PM EST THIS AFTERNOON FOR NCZ033- 048>053-058-059-062>065-501-503-505-507-509.

SC...NONE. &&

$$

SHORT TERM...HG FIRE WEATHER...HG

.SHORT TERM /TODAY THROUGH MONDAY/... EXPECT A FEW FLURRIES THIS MORNING ACROSS THE NORTHERN MOUNTAINS OF NORTH CAROLINA. AIRMASS DRIES OUT THIS AFTERNOON TO THE POINT WHERE FLURRIES SHOULD END. WINDY CONDITIONS WILL PREVAIL ACROSS THE NC MOUNTAINS...AND A LAKE WIND ADVISORY WILL BE NEEDED THERE. I/M JUST GOING BREEZY FOR NOW ACROSS THE UPSTATE AND NE GA...BUT DEPENDING ON THE DEPTH OF THE MIXING...A FEW HOURS OF WINDY CONDITIONS ARE QUITE POSSIBLE IN THESE AREAS BY MID AFTERNOON.

LATE TONIGHT A WEAKENING SHORT WAVE WILL APPROACH THE NC MOUNTAINS. 1000-500MB LAYER RH/S INCREASE TO OVER 70 PERCENT ALONG THE TN LINE BETWEEN 9 AND 12 UTC. WHILE THE LOW LEVEL FLOW IS OUT OF THE WEST...WHICH IS NOT OPTIMAL FOR UPSLOPE SNOW SHOWERS...THE WINDS ARE FAIRLY STRONG AT 30 TO 40 KTS. WITH H8 TEMPS AROUND -10 DEG C...THIS SHOULD BE ADEQUATE FOR SNOW SHOWERS FROM MADISON CO NORTHWARD. WENT ON THE COOL SIDE OF MOS TODAY AND TONIGHT.

SNOW SHOWERS WILL LINGER ALONG THE TENN BORDER SUN MORNING...BUT MOISTURE IS EXPECTED TO DIMINISH BY EARLY PM. THIS WILL GIVE WAY TO A DRY BUT SEASONABLY COOL END TO THE WEEKEND.

A STRONG SW TROUGH DIVING OUT OF THE UPPER MIDWEST WILL DEEPEN THE EASTERN TROUGH EARLY NEXT WEEK...SENDING A REINFORCING SHOT OF COLD AIR INTO THE REGION BY EARLY MONDAY. AS A RESULT...MONDAY/S MAX TEMPS WILL LIKELY RANGE FROM THE LOW TEENS IN THE HIGHER ELEVATIONS...TO THE MID AND UPPER 20S IN THE VALLEYS...TO THE MID AND UPPER 30S ACROSS MOST OF THE PIEDMONT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... EASTERN LONG WAVE TROUGH WILL CONTINUE TO DOMINATE THE WEATHER THROUGH AT LEAST MID-WEEK. THIS WILL RESULT IN A MOSTLY DRY FORECAST THROUGH THE PERIOD. THE MAIN STORY WILL BE THE COLD...AS TEMPS SHOULD REMAIN BELOW...EVEN WELL BELOW NORMAL THROUGH MID-WEEK... WHEN THE LARGE SCALE FLOW WILL TAKE ON A MORE ZONAL CONFIGURATION ACROSS THE EASTERN STATES. HOWEVER...ANOTHER STRONG SW TROUGH DIVING OUT OF THE UPPER MIDWEST WILL LIKELY SEND ANOTHER SHOT OF COLD AIR INTO THE REGION LATE NEXT WEEK.

&&

.AVIATION /07Z-06Z/... WITH A MUCH DRIER AIRMASS WORKING INTO THE REGION...AND WITH MANY TAF SITES REMAINING MIXED THROUGH SUNRISE...DON/T SEE ANY FOG OR STRATUS CONCERNS THIS MORNING. WINDS WILL GRADUALLY INCREASE INTO THE EARLY AFTERNOON HOURS OUT OF THE WSW. THERE WILL BE DEEP MIXING THIS AFTERNOON...AND GUSTS INTO THE MID 20KT RANGE ARE POSSIBLE JUST ABOUT ANYWHERE...BUT ESPECIALLY ACROSS THE UPSTATE. AT KAVL WINDS WILL BE MORE NORTHWESTERLY...BUT AS MIXING DEEPENS DURING THE AFTERNOON HOURS...WOULDN/T BE SURPRISED TO SEE THEM TURN OUT OF THE WEST AT TIMES. THIS WILL MAKE FOR QUITE A BIT OF LOW LEVEL TURBULENCE...SOMETHING SMALLER AIRCRAFT WILL NEED TO BE WARY OF.

&&

.FIRE WEATHER... DEWPOINTS SHOULD MIX OUT INTO THE SINGLE DIGITS IN THE NORTH CAROLINA ZONES THIS AFTERNOON. WITH A WESTERLY DOWNSLOPE FLOW...DEWPOINTS COULD BECOME ESPECIALLY LOW ACROSS THE FRENCH BROAD VALLEY AND THE NC FOOTHILLS...WITH RH/S FALLING WELL INTO THE TEENS BY LATE AFTERNOON. ELSEWHERE...RH/S WILL STILL FALL AT LEAST INTO THE L-M20S. SO...ACROSS THE MOUNTAINS...THE UPSTATE AND NE GA THERE IS A GOOD CHANCE OF MEETING METEOROLOGICAL RED FLAG CRITERIA. HOWEVER...CALLS TO LAND MANAGEMENT AGENCIES YESTERDAY REVEALED THAT FUEL MOISTURE IS VERY HIGH...SO THE FIRE DANGER IS NOT HIGH ENOUGH TO WARRANT A RED FLAG WARNING.

&&

.GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...LAKE WIND ADVISORY FOR ALL MOUNTAIN ZONES. SC...NONE. &&

$$

SHORT TERM...MCAVOY/LANE LONG TERM...LANE AVIATION/FIRE WEATHER...MCAVOY

.AVIATION... 1100 AM VFR THROUGH TODAY...NO PROBLEMS EXPECTED. WILL WRITE SOME 3SM BR IN FOR SUNDAY MORNING. WEAK BOUNDARY MOVES INTO AREA OVERNIGHT AND MODEL SOUNDINGS SHOW LOW LEVEL SATURATION WITH VERY LIGHT WINDS. ATMOSPHERE TOO DRY TO SUPPORT DENSE FOG. 84

&&

.DISCUSSION... 1040 AM LIGHT WINDS...CLEAR SKIES...AND LOW DEWPOINTS ALLOWED TEMPERATURES TO FALL INTO THE UPPER TEENS TO MID 20S ACROSS NORTH TEXAS OVERNIGHT. TEMPERATURES ARE WARMING UP QUICKLY...AFTER A VERY COLD START THIS MORNING. AS OF 10 AM...TEMPERATURES HAD WARMED INTO THE MID TO UPPER 30S. SOUTHERLY WINDS OF 10 TO 15 WITH GUSTS TO OVER 20 MPH WILL OCCUR THIS AFTERNOON. THE PREVIOUS FORECAST IS IN PRETTY GOOD SHAPE...AND ONLY MINOR ADJUSTMENTS WERE MADE TO THE FIRST PERIOD FORECAST. #58

&&

.PREV DISCUSSION... /ISSUED 515 AM CST SAT FEB 3 2007/

.PREV AVIATION... VFR CONDITIONS FOR BOTH KDFW AND KACT TRACONS TODAY AND TONIGHT. SURFACE HIGH PRESSURE IS CENTER OVER NEAR KCLL THIS MORNING AND WILL SLIDE TO THE TEXAS COAST THIS AFTERNOON...THEN INTO THE SOUTHERN ALABAMA BY 12Z SUNDAY. WINDS WILL BE SOUTH TO SOUTHWEST 8-14 KNOTS TODAY...THEN WEAKENING TO 4-7 KNOTS OVERNIGHT. KACT WILL SEE SOME SCATTERED MID/HIGH LEVEL CLOUDS AND A SIMILAR WIND TREND AS WELL.

SUB-FREEZING TEMPERATURES WILL PERSIST UNTIL MID MORNING. THIS WILL LIKELY RESULT IN A HEAVY FROST COATING AIRCRAFT PARKED OVERNIGHT. 75

PREV DISCUSSION... / ISSUED 222 AM CST SAT FEB 3 2007 / STARTING OFF THE DAY WITH A CHILLY MORNING IN DRY/POLAR AIRMASS WITH LIGHT WINDS. MORNING LOWS THE COLDEST WE`VE SEEN IN AWHILE THIS WINTER SEASON WITH 20S AREAWIDE...WITH POSSIBLE UPPER TEENS ACROSS SHELTERED AREAS OF THE WRN/NRN COUNTIES. SHOULD BE SOME FROST AND POSSIBLE SHALLOW...FREEZING GROUND FOG...BUT NOTHING TOO BAD OR WIDESPREAD. MAY ADD PATCHY FOG IN FCST EARLY THIS MORNING.

OTHERWISE...THE WARMING/MODIFICATION PROCESS BEGINS TODAY AND INTO MONDAY...AS CANADIAN MID LVL POLAR VORTEX OVER WRN ONTARIO SHIFTS EWD OVER THE CANADIAN MARITIMES DURING THIS TIME...AND MID LVL RIDGE AMPLIFIES OVER THE WRN CONUS. MEANWHILE...LOW LVL WAA WILL GET GOING AS SLY COMPONENT BEGINS. TEMPERED WARM UP MORE TOWARD LOW GFS ENSEMBLE MOS NUMBERS TODAY WITH A LARGE TEMP CONTRAST FROM NE-SW (COLDER...WARMER RESPECTIVELY)...THEN WARM IT UP ANOTHER COUPLE OF CATEGORIES INTO SUN. JUST IN TIME FOR YOU WEEKEND ENTHUSIASTS. A BACK-DOOR COLD FRONT WILL ENTER FROM THE NE ON MONDAY AND HAVE LOWERED TEMPS ACROSS THE NE 1/2 OF N TX WITH THIS IN MIND...BUT NOT TOO TERRIBLY COLD WITH TEMPS 45-50 NORTH ...IN THE 50S TO NEAR 60 SOUTH. MID LVL S/W DROPS OUT OF ROCKIES AND OVER TX MON AFTN/NIGHT ..BUT FEEL LOW LVL MSTR IS TOO SHALLOW WITH VERY DRY MID LVL AIR FOR ANY RAIN CHANCES. AIRMASS WILL MOISTEN/WARM TUES/WED AS MID LVL RIDGE EXPANDS OVERHEAD AND NIGHTLY LLJ TRANSPORTS SOME MODIFIED MSTR NWD. NEAR SEASONABLE TEMPS FOR EARLY FEBRUARY EXPECTED MID WEEK.

SOME CHANGES ARRIVE LATE WEEK AS MID LVL RIDGE WEAKENS AND ERN CONUS POLAR VORTEX RETROGRADES WWD SOME...ALLOW FOR MORE MID LVL ENERGY AND ARRIVAL OF SOME COLD AIR ONCE AGAIN BY THE WEEKEND. TIMING OF FEATURES/QPF/COLDER AIR TOUGH TO ASCERTAIN...SO KEPT THINGS A COLD RAIN AND WENT MIDDLE OF THE ROAD WITH TEMPS...BUT GENERALLY ON THE LOWER END OF THE GFS ENSEMBLE MOS NUMBERS WHICH MATCH UP WELL WITH ECMWF PROJECTION OF PATTERN. IF BACK-DOOR AIRMASS THURS INTO FRI IS COLDER THAN EXPECTED...COULD SEE A FZRA POTENTIAL NEAR IMMEDIATE RED RIVER VALLEY...BUT LAID OFF THAT FOR NOW. EVEN COLDER...SHALLOW AIRMASS ARRIVES NEXT WEEKEND...BUT LEFT ANY PRECIP CHANCES OUT WITH MOISTURE AVAILABILITY IN QUESTION.

&&

.PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 48 33 57 36 49 / 0 0 0 0 0 WACO, TX 52 35 62 40 55 / 0 0 0 0 0 PARIS, TX 44 29 52 31 45 / 0 0 0 0 10 DENTON, TX 48 30 56 32 48 / 0 0 0 0 0 MCKINNEY, TX 47 30 54 33 48 / 0 0 0 0 10 DALLAS, TX 48 35 57 38 50 / 0 0 0 0 0 TERRELL, TX 48 33 56 38 51 / 0 0 0 0 10 CORSICANA, TX 51 34 59 40 53 / 0 0 0 0 10 TEMPLE, TX 55 36 63 42 57 / 0 0 0 0 0

&&

.FWD WATCHES/WARNINGS/ADVISORIES... NONE. &&

$$

84/58

.DISCUSSION... LIGHT WINDS...CLEAR SKIES...AND LOW DEWPOINTS ALLOWED TEMPERATURES TO FALL INTO THE UPPER TEENS TO MID 20S ACROSS NORTH TEXAS OVERNIGHT. TEMPERATURES ARE WARMING UP QUICKLY...AFTER A VERY COLD START THIS MORNING. AS OF 10 AM...TEMPERATURES HAD WARMED INTO THE MID TO UPPER 30S. SOUTHERLY WINDS OF 10 TO 15 WITH GUSTS TO OVER 20 MPH WILL OCCUR THIS AFTERNOON. THE PREVIOUS FORECAST IS IN PRETTY GOOD SHAPE...AND ONLY MINOR ADJUSTMENTS WERE MADE TO THE FIRST PERIOD FORECAST. #58

&&

.PREV DISCUSSION... /ISSUED 515 AM CST SAT FEB 3 2007/

AVIATION... VFR CONDITIONS FOR BOTH KDFW AND KACT TRACONS TODAY AND TONIGHT. SURFACE HIGH PRESSURE IS CENTER OVER NEAR KCLL THIS MORNING AND WILL SLIDE TO THE TEXAS COAST THIS AFTERNOON...THEN INTO THE SOUTHERN ALABAMA BY 12Z SUNDAY. WINDS WILL BE SOUTH TO SOUTHWEST 8-14 KNOTS TODAY...THEN WEAKENING TO 4-7 KNOTS OVERNIGHT. KACT WILL SEE SOME SCATTERED MID/HIGH LEVEL CLOUDS AND A SIMILAR WIND TREND AS WELL.

SUB-FREEZING TEMPERATURES WILL PERSIST UNTIL MID MORNING. THIS WILL LIKELY RESULT IN A HEAVY FROST COATING AIRCRAFT PARKED OVERNIGHT. 75

PREV DISCUSSION... / ISSUED 222 AM CST SAT FEB 3 2007 / STARTING OFF THE DAY WITH A CHILLY MORNING IN DRY/POLAR AIRMASS WITH LIGHT WINDS. MORNING LOWS THE COLDEST WE`VE SEEN IN AWHILE THIS WINTER SEASON WITH 20S AREAWIDE...WITH POSSIBLE UPPER TEENS ACROSS SHELTERED AREAS OF THE WRN/NRN COUNTIES. SHOULD BE SOME FROST AND POSSIBLE SHALLOW...FREEZING GROUND FOG...BUT NOTHING TOO BAD OR WIDESPREAD. MAY ADD PATCHY FOG IN FCST EARLY THIS MORNING.

OTHERWISE...THE WARMING/MODIFICATION PROCESS BEGINS TODAY AND INTO MONDAY...AS CANADIAN MID LVL POLAR VORTEX OVER WRN ONTARIO SHIFTS EWD OVER THE CANADIAN MARITIMES DURING THIS TIME...AND MID LVL RIDGE AMPLIFIES OVER THE WRN CONUS. MEANWHILE...LOW LVL WAA WILL GET GOING AS SLY COMPONENT BEGINS. TEMPERED WARM UP MORE TOWARD LOW GFS ENSEMBLE MOS NUMBERS TODAY WITH A LARGE TEMP CONTRAST FROM NE-SW (COLDER...WARMER RESPECTIVELY)...THEN WARM IT UP ANOTHER COUPLE OF CATEGORIES INTO SUN. JUST IN TIME FOR YOU WEEKEND ENTHUSIASTS. A BACK-DOOR COLD FRONT WILL ENTER FROM THE NE ON MONDAY AND HAVE LOWERED TEMPS ACROSS THE NE 1/2 OF N TX WITH THIS IN MIND...BUT NOT TOO TERRIBLY COLD WITH TEMPS 45-50 NORTH ...IN THE 50S TO NEAR 60 SOUTH. MID LVL S/W DROPS OUT OF ROCKIES AND OVER TX MON AFTN/NIGHT ..BUT FEEL LOW LVL MSTR IS TOO SHALLOW WITH VERY DRY MID LVL AIR FOR ANY RAIN CHANCES. AIRMASS WILL MOISTEN/WARM TUES/WED AS MID LVL RIDGE EXPANDS OVERHEAD AND NIGHTLY LLJ TRANSPORTS SOME MODIFIED MSTR NWD. NEAR SEASONABLE TEMPS FOR EARLY FEBRUARY EXPECTED MID WEEK.

SOME CHANGES ARRIVE LATE WEEK AS MID LVL RIDGE WEAKENS AND ERN CONUS POLAR VORTEX RETROGRADES WWD SOME...ALLOW FOR MORE MID LVL ENERGY AND ARRIVAL OF SOME COLD AIR ONCE AGAIN BY THE WEEKEND. TIMING OF FEATURES/QPF/COLDER AIR TOUGH TO ASCERTAIN...SO KEPT THINGS A COLD RAIN AND WENT MIDDLE OF THE ROAD WITH TEMPS...BUT GENERALLY ON THE LOWER END OF THE GFS ENSEMBLE MOS NUMBERS WHICH MATCH UP WELL WITH ECMWF PROJECTION OF PATTERN. IF BACK-DOOR AIRMASS THURS INTO FRI IS COLDER THAN EXPECTED...COULD SEE A FZRA POTENTIAL NEAR IMMEDIATE RED RIVER VALLEY...BUT LAID OFF THAT FOR NOW. EVEN COLDER...SHALLOW AIRMASS ARRIVES NEXT WEEKEND...BUT LEFT ANY PRECIP CHANCES OUT WITH MOISTURE AVAILABILITY IN QUESTION.

&&

.PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 48 33 57 36 49 / 0 0 0 0 0 WACO, TX 52 35 62 40 55 / 0 0 0 0 0 PARIS, TX 44 29 52 31 45 / 0 0 0 0 10 DENTON, TX 48 30 56 32 48 / 0 0 0 0 0 MCKINNEY, TX 47 30 54 33 48 / 0 0 0 0 10 DALLAS, TX 48 35 57 38 50 / 0 0 0 0 0 TERRELL, TX 48 33 56 38 51 / 0 0 0 0 10 CORSICANA, TX 51 34 59 40 53 / 0 0 0 0 10 TEMPLE, TX 55 36 63 42 57 / 0 0 0 0 0

&&

.FWD WATCHES/WARNINGS/ADVISORIES... NONE. &&

$$

84/58

.AVIATION... VFR CONDITIONS FOR BOTH KDFW AND KACT TRACONS TODAY AND TONIGHT. SURFACE HIGH PRESSURE IS CENTER OVER NEAR KCLL THIS MORNING AND WILL SLIDE TO THE TEXAS COAST THIS AFTERNOON...THEN INTO THE SOUTHERN ALABAMA BY 12Z SUNDAY. WINDS WILL BE SOUTH TO SOUTHWEST 8-14 KNOTS TODAY...THEN WEAKENING TO 4-7 KNOTS OVERNIGHT. KACT WILL SEE SOME SCATTERED MID/HIGH LEVEL CLOUDS AND A SIMILAR WIND TREND AS WELL.

SUB-FREEZING TEMPERATURES WILL PERSIST UNTIL MID MORNING. THIS WILL LIKELY RESULT IN A HEAVY FROST COATING AIRCRAFT PARKED OVERNIGHT. 75

&&

.PREV DISCUSSION... / ISSUED 222 AM CST SAT FEB 3 2007 / STARTING OFF THE DAY WITH A CHILLY MORNING IN DRY/POLAR AIRMASS WITH LIGHT WINDS. MORNING LOWS THE COLDEST WE`VE SEEN IN AWHILE THIS WINTER SEASON WITH 20S AREAWIDE...WITH POSSIBLE UPPER TEENS ACROSS SHELTERED AREAS OF THE WRN/NRN COUNTIES. SHOULD BE SOME FROST AND POSSIBLE SHALLOW...FREEZING GROUND FOG...BUT NOTHING TOO BAD OR WIDESPREAD. MAY ADD PATCHY FOG IN FCST EARLY THIS MORNING.

OTHERWISE...THE WARMING/MODIFICATION PROCESS BEGINS TODAY AND INTO MONDAY...AS CANADIAN MID LVL POLAR VORTEX OVER WRN ONTARIO SHIFTS EWD OVER THE CANADIAN MARITIMES DURING THIS TIME...AND MID LVL RIDGE AMPLIFIES OVER THE WRN CONUS. MEANWHILE...LOW LVL WAA WILL GET GOING AS SLY COMPONENT BEGINS. TEMPERED WARM UP MORE TOWARD LOW GFS ENSEMBLE MOS NUMBERS TODAY WITH A LARGE TEMP CONTRAST FROM NE-SW (COLDER...WARMER RESPECTIVELY)...THEN WARM IT UP ANOTHER COUPLE OF CATEGORIES INTO SUN. JUST IN TIME FOR YOU WEEKEND ENTHUSIASTS. A BACK-DOOR COLD FRONT WILL ENTER FROM THE NE ON MONDAY AND HAVE LOWERED TEMPS ACROSS THE NE 1/2 OF N TX WITH THIS IN MIND...BUT NOT TOO TERRIBLY COLD WITH TEMPS 45-50 NORTH ...IN THE 50S TO NEAR 60 SOUTH. MID LVL S/W DROPS OUT OF ROCKIES AND OVER TX MON AFTN/NIGHT ...BUT FEEL LOW LVL MSTR IS TOO SHALLOW WITH VERY DRY MID LVL AIR FOR ANY RAIN CHANCES. AIRMASS WILL MOISTEN/WARM TUES/WED AS MID LVL RIDGE EXPANDS OVERHEAD AND NIGHTLY LLJ TRANSPORTS SOME MODIFIED MSTR NWD. NEAR SEASONABLE TEMPS FOR EARLY FEBRUARY EXPECTED MID WEEK.

SOME CHANGES ARRIVE LATE WEEK AS MID LVL RIDGE WEAKENS AND ERN CONUS POLAR VORTEX RETROGRADES WWD SOME...ALLOW FOR MORE MID LVL ENERGY AND ARRIVAL OF SOME COLD AIR ONCE AGAIN BY THE WEEKEND. TIMING OF FEATURES/QPF/COLDER AIR TOUGH TO ASCERTAIN...SO KEPT THINGS A COLD RAIN AND WENT MIDDLE OF THE ROAD WITH TEMPS...BUT GENERALLY ON THE LOWER END OF THE GFS ENSEMBLE MOS NUMBERS WHICH MATCH UP WELL WITH ECMWF PROJECTION OF PATTERN. IF BACK-DOOR AIRMASS THURS INTO FRI IS COLDER THAN EXPECTED...COULD SEE A FZRA POTENTIAL NEAR IMMEDIATE RED RIVER VALLEY...BUT LAID OFF THAT FOR NOW. EVEN COLDER...SHALLOW AIRMASS ARRIVES NEXT WEEKEND...BUT LEFT ANY PRECIP CHANCES OUT WITH MOISTURE AVAILABILITY IN QUESTION.

&&

.PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 48 33 57 36 50 / 0 0 0 0 0 WACO, TX 52 35 62 40 55 / 0 0 0 0 0 PARIS, TX 44 29 52 31 41 / 0 0 0 0 10 DENTON, TX 48 30 56 32 48 / 0 0 0 0 0 MCKINNEY, TX 47 30 54 33 47 / 0 0 0 0 10 DALLAS, TX 48 35 57 38 51 / 0 0 0 0 0 TERRELL, TX 48 33 56 38 51 / 0 0 0 0 10 CORSICANA, TX 51 34 59 40 54 / 0 0 0 0 10 TEMPLE, TX 55 36 63 42 57 / 0 0 0 0 0

&&

.FWD WATCHES/WARNINGS/ADVISORIES... NONE. &&

$$

/05

.SYNOPSIS...HIGH PRESSURE BUILDING ALOFT WILL ALLOW FOR SLOWLY CLEAR SKIES THROUGH MONDAY. HOWEVER LIGHT WINDS AT THE SURFACE AND PLENTY OF MOISTURE WILL BRING ABOUT PLENTY OF FOG OVERNIGHT THAT WILL LAST UNTIL MONDAY MORNING. A LOW PRESSURE SYSTEM IS EXPECTED TO APPROACH LATE TUESDAY...RESULTING IN A CHANCE OF RAIN OVER SOUTHWEST WASHINGTON IN THE AFTERNOON. LOOK FOR UNSETTLED WEATHER THE REMAINDER OF THE WEEK.

&&

.SHORT TERM...A FEW SHOWERS STILL JUST CATCHING THE NORTHERN PART OF THE AREA SO WILL NEED TO LEAVE A LOW CHANCE THERE FOR THE EARLY EVENING BUT FOR THE REMAINDER OF THE AREA WILL JUST GO WITH MOSTLY CLOUDY. ACARS SOUNDINGS CONTINUE TO INDICATE A LOW LEVEL INVERSION WITH THE TOPS NEAR 1500 FT. VERY LITTLE WIND BELOW THIS TO MIX THINGS UP WITH PLENTY OF LOW LEVEL MOISTURE. THIS SITUATION WILL REMAIN INTO MIDDAY MONDAY...SO STAGNANT CONDITIONS TIL THEN WHICH WILL BRING ABOUT SOME RATHER DECENT FOG DEVELOPMENT OVERNIGHT WHICH WILL LAST INTO THE FIRST PART OF MONDAY.

IF ALL GOES ACCORDING TO PLAN...THE SUN WILL BUST THROUGH LATER MONDAY FOR A DECENT AFTERNOON. GOING FOR THE LOWER 50S GENERALLY BUT THAT WILL DEPEND HEAVILY ON HOW MUCH SUN WE GET. COULD GO EITHER SIDE OF THAT FORECAST. MONDAY NIGHT WILL BE UNEVENTFUL AS WELL WITH PARTLY CLOUDY SKIES AND SOME FOG DEVELOPING AGAIN.

FOR TUESDAY...AT THIS POINT GOING WITH THE IDEA THAT MOST OF THE AREA SHOULD BE DRY MOST OF THE DAY. WEAK SYSTEM IS FORECAST TO MOVE NORTHWARD ALONG THE COAST AND GENERATE SOME LIGHT PRECIP ACROSS THE AREA LATE IN THE PERIOD. IT LOOKS LATE ENOUGH AND WEAK ENOUGH TO WARRANT LEAVING MENTION OF RAIN OUT OF MOST OF THE AREA FOR THE PRE-00Z TIME FRAME. CONTINUED THE MENTION OF CHANCE OF RAIN TUESDAY NIGHT AS THAT WOULD BE A BETTER BET. CERNIGLIA

.LONG TERM...FOR WEDNESDAY ONWARD...THE MOISTURE TAP IS BEING OPENED BUT IT LOOKS LIKE IT WILL BE AN INTERMITTENT SPRINKLER. BASICALLY HAVE A WEAK RIDGE AXIS DRAPED NW-SE ACROSS WASHINGTON WITH SYSTEMS APPROACHING FROM THE SOUTH-SOUTHWEST. AT LEAST THROUGH SAT THAT MEANS THAT THE SYSTEMS ARE IN THE PROCESS OF WEAKENING AS THEY APPROACH OUR AREA. SO WHILE PLENTY OF MOISTURE ROLLS UP ACROSS US WITH EACH FRONTAL SYSTEM...DYNAMICS RATHER WEAK. SO WE ARE EXPECTING MANY PERIODS OF RAIN (INTERSPERSED WITH PERIODS OF NO RAIN) THE RAIN SHOULD BE MAINLY OF THE LIGHTER VARIETY. LOOKS LIKE WE SHOULD HAVE A FRONTAL BAND AFFECT THE AREA LATER WED...THEN SEVERAL...DIFFICULT TO TIME SYSTEMS THROUGH SUNDAY. THEREFORE THE SOMEWHAT OF A BROADBRUSH FOR THE EXTENDED PERIOD. CERNIGLIA

&&

.AVIATION...BETWEEN BELLINGHAM TO WHIDBEY ISLAND IFR CONDITIONS CONTINUING THROUGH THE EVENING WITH LIGHT RAIN LOWERING VISIBILITIES DOWN TO 1 TO 3 SM UNTIL 05Z. WHIDBEY ISLAND TO SEATTLE SCATTERED LAYER AROUND 2500 FEET WITH MID LEVEL DECK AROUND 7000 FEET. ISOLATED VISIBILITIES 3-5SM IN FOG. SEATTLE SOUTH SCATTERED CLOUDS THIS EVENING. LIGHT SURFACE GRADIENTS AND LIGHT WINDS JUST OFF THE GROUND. WITH PLENTY OF LOW LEVEL MOISTURE EXPECT ALL AREAS TO LOWER BACK DOWN TO IFR OR LOWER CEILINGS AND VISIBILITIES BETWEEN 05Z-10Z. CEILINGS BELOW 500 FEET AND VISIBILITIES 3 MILES OR LESS CONTINUING THROUGH THE MORNING HOURS ON MONDAY.

FOR KSEA...SCATTERED TO BROKEN MID LEVEL DECK THROUGH THE EARLY EVENING HOURS. CONDITIONS BEGINNING TO DETERIORATE AFTER 05Z WITH CEILINGS BELOW 200 FEET AND VISIBILITIES BELOW 1/2 MILE AFT 09Z. CONDITIONS BEGINNING TO IMPROVE AFTER 17Z MON MORNING. WINDS LIGHT AND VARIABLE. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...NONE.

$$

WEATHER.GOV/SEATTLE

.SHORT TERM... ANOTHER COLD NIGHT IN STORE...AS CLOUDS FROM LAKE MICHIGAN HAVE STRUGGLED TO ADVANCE EASTWARD...EVEN WITH THE DIURNAL ENHANCEMENT HELPING TO RAISE INVERSION HEIGHTS UP TOWARD 4000 FEET PER DTW TAMDAR DATA. THE GOOD NEWS IS THE SUNSHINE HAS HELPED BOOST MAX TEMPS TO AROUND 10 DEGREES THIS AFTERNOON...A GOOD 3-5 DEGREES WARMER COMPARED TO YESTERDAY.

PRESSURE GRADIENT OVER SOUTHERN LOWER MICHIGAN TONIGHT LOOKS TO BE ABOUT 2 MB LESS WHEN COMPARED TO THIS MORNING. THIS SHOULD TRANSLATE TO LOWS AT OR BELOW ZERO EVERYWHERE...AND HAVE UNDERCUT GFS MOS GUIDANCE BY A GOOD 5 DEGREES IN MOST SPOTS. A FAR AS WIND CHILLS GO...WITH THE WEAKER GRADIENT...WINDS LOOK TO BE BORDERLINE...AROUND 10 MPH...WITH WIND CHILLS HOVERING RIGHT AROUND -20 F (ADVISORY CRITERIA). WILL HOLD OFF ON THE ADVISORY...AS WIND CHILLS OF -20 F OR COLDER ARE NOT EXPECTED TO BE WIDESPREAD...NOR ARE THEY EXPECTED FOR AN EXTENDED PERIOD OF TIME.

DRY AIRMASS CONTINUES TO LIMIT LAKE EFFECT ACTIVITY...AND SEE NO SIGNIFICANT CHANGES INTO TONIGHT. THE WESTERN CLOUD EDGE/CONDENSATION OVER LAKE MICHIGAN HAS ACTUALLY BEEN PULLING EAST THIS AFTERNOON.

TOMORROW LOOKS TO BE A DIFFERENT STORY...AS UPPER WAVE CURRENTLY OVER NORTHERN ALBERTA QUICKLY DIVES SOUTHEAST...TRACKING ALONG THE SOUTHERN MICHIGAN BORDER...PER NAM/GFS TROPOPAUSE PRESSURE FIELDS. THIS SHOULD AT LEAST ALLOW FOR AN ENHANCEMENT TO THE I-94/M-59 CONVERGENT BAND. HOWEVER...MODELS IMPLYING MOST/ALL OF THE SYNOPTIC SNOW WILL STAY SOUTH OF THE BORDER AS MAIN 850-700 MB THETA GRADIENT REMAINS CONFINED TO THE SOUTHERN OHIO VALLEY...WITH LITTLE IN THE WAY OF MOISTURE TRANSPORT INTO SOUTHERN LOWER MICHIGAN. STILL A LITTLE LEARY THE UPPER WAVE MAY BE DRAWN A LITTLE FARTHER NORTH THAN INDICATED...AND WILL CARRY A 50 POP FOR M-59 AND POINTS SOUTH. NO CHANGES TO MAXES TOMORROW...LOWER TEENS EXPECTED.

&&

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

VERY LITTLE CHANGE IN THE ONGOING PATTERN THROUGH THE WEEKEND AS SEVERAL STRONG SHORTWAVES DIG INTO THE EASTERN NORTH AMERICAN UPPER TROUGH AND KEEP THE EASTERN CANADIAN POLAR VORTEX WELL-ESTABLISHED. THIS WILL MAINTAIN A COLD AIRMASS ACROSS THE REGION WITH HIGHS ONLY IN THE TEENS/LOWER 20S AND LOWS IN THE SINGLE DIGITS TO OCCASIONALLY BELOW ZERO.

THE FIRST OF THESE SHORTWAVES WILL BE PASSING SOUTH OF THE REGION TUESDAY EVENING. THERE MAY BE SOME LEFTOVER LIGHT SNOW OVER THE FAR SOUTHERN CWA FROM THIS SYSTEM (OR AT LEAST AN ENHANCEMENT TO LAKE EFFECT SNOW SHOWERS FROM THE MOISTURE IT WILL BRING)...BUT OVERALL IT WILL JUST ENSURE THAT THE STATUS QUO HOLDS...AND WE REMAIN IN THE SAME TEMPERATURE REGIME. THE NEXT SHORTWAVE WILL DROP DOWN FROM THE ARCTIC CIRCLE AND SPIN AROUND THE POLAR VORTEX. SO...EXPECT THIS FEATURE TO BRING A RESURGENCE OF COLDER AIR BY LATE FRIDAY INTO SATURDAY. ATTM...IT APPEARS THIS AIRMASS IS SOME 5-7 DEGREES C MILDER THAN THE ARCTIC AIRMASS OF THIS PAST WEEKEND...SO DO NOT EXPECT TEMPERATURES TO STRUGGLE QUITE AS MUCH.

THE FORECAST FOR SNOW SHOWERS REMAINS TRICKY...AT LEAST IN TRYING TO PICK OUT THE DAY(S) THAT HAVE THE BEST CHANCE OF LIGHT ACCUMULATION. NO LARGE STORM SYSTEMS ARE ON THE WAY...AND ANY ACCUMULATING SNOWS WILL MAINLY BE LAKE EFFECT/ENHANCED SNOW SHOWERS. AFTER A PERIOD OF ENHANCED SNOW SHOWER ACTIVITY TO START THE LONG TERM FORECAST...THE GENERAL FORECAST WILL BE FOR PERIODIC FLURRIES IN THE WEDNESDAY AND THURSDAY TIMEFRAME...WITH MORE WIDESPREAD SNOW SHOWERS BY FRIDAY AND SATURDAY AS THE AFOREMENTIONED ARCTIC SHORTWAVE DIVES THROUGH THE GREAT LAKES.

AT THE VERY END OF THE FORECAST...THE AMPLIFIED PATTERN CONTINUES TO SHOW SOME SIGNS OF RELAXING...WHICH WOULD ALLOW MORE INTRUSION OF PACIFIC AIR INTO THE REGION...AND LESS INTRUSION OF THE COLDEST AIR FROM THE ARCTIC. WILL MAINTAIN THE SLIGHT MODERATION IN THE SUNDAY TO MONDAY TIMEFRAME GIVEN SOME CONSISTENCY IN GFS RUNS DURING THE PAST FEW DAYS FOR THIS BASIC SCENARIO. STILL...TEMPERATURES SHOULD REMAIN LARGELY BELOW NORMAL.

&&

.PREV DISCUSSION...ISSUED 1210 PM EST MON FEB 5 2007

AVIATION...

BOUNDARY LAYER/INVERSION HEIGHTS ARE RISING THIS AFTERNOON...WHICH SHOULD ALLOW MVFR CEILINGS COMING OFF LAKE MICHIGAN TO FILTER INTO SOUTHEAST MICHIGAN...ESPECIALLY OVER THE DETROIT TAFS...WHERE I-94 CONVERGENT BAND LOOKS TO PERSIST. INVERSION HEIGHTS EXPECTED TO REMAIN AT OR ABOVE 4000 FEET TONIGHT AND TOMORROW MORNING. HOWEVER...LOSS OF DIURNAL COMPONENT STILL MAKES IT A TOUGH CALL WHETHER OR NOT TO CONTINUE MVFR CEILINGS AND SCATTERED SNOW SHOWERS/FLURRIES TONIGHT. WITH THE WESTERLY FLOW AND BASED ON THE 925 MB OMEGA FIELDS...WILL CARRY THE MVFR CEILINGS AND SNOW SHOWERS LONGEST OVER THE DETROIT TAF SITES.

&&

.DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...GALE WARNING...NORTH HALF UNTIL 1 PM TUESDAY

GALE WARNING...SOUTH HALF UNTIL 7 AM TUESDAY.

SMALL CRAFT ADVISORY...LHZ441-LHZ442 UNTIL 7 PM WEDNESDAY.

SMALL CRAFT ADVISORY...LHZ421-LHZ443 UNTIL 7 AM TUESDAY.

SMALL CRAFT ADVISORY FOR WINDS...LHZ422 UNTIL 7 AM TUESDAY.

LAKE ST CLAIR...SMALL CRAFT ADVISORY FOR WINDS...LCZ460 UNTIL 7 AM TUESDAY.

MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY FOR WINDS...UNTIL 7 AM TUESDAY.

&&

$$

SHORT TERM...SF LONG TERM....DG AVIATION.....SF

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

.SYNOPSIS...LIGHT FLOW WITH PLENTY OF MOISTURE AT THE LOWER LEVELS COMBINING TO CREATE FOGGY CONDITIONS OVER THE AREA THROUGH THIS AFTERNOON. CONDITIONS WILL IMPROVE BRIEFLY BUT MORE FOG IS EXPECTED TO FORM OVERNIGHT INTO TUESDAY MORNING. AN APPROACHING LOW PRESSURE SYSTEM WILL BRING A CHANCE OF RAIN TO SOUTHWEST WASHINGTON TUESDAY AFTERNOON AND THE REST OF THE AREA TUESDAY NIGHT. ANTICIPATE WET WEATHER ON WEDNESDAY. &&

.SHORT TERM...FIRST VISIBLE SATELLITE IMAGES THIS MORNING SHOW FOG/STRATUS NEAR THE SOUND...DOWN THE I-5 CORRIDOR AND ALONG THE COAST. QUESTION FOR TODAY IS HOW LONG THE FOG WILL LAST. MORNING TOP REPORTS OUT OF KSEA AND KBFI AROUND 2000 FEET. SATELLITE IMAGERY SHOWS THE CASCADE FOOTHILLS ARE CLEAR THIS MORNING. GRADIENTS ARE LIGHT OFFSHORE AND NOT EXPECTED TO CHANGE MUCH TODAY. ACARS SOUNDINGS SHOW A GOOD INVERSION OVER WESTERN WASHINGTON WITH THE TEMPERATURES AT 3000 FEET NEAR 50 DEGREES AND WINDS BELOW 850 MB LESS THAN 10 KNOTS. WITH THESE VARIABLES WILL UPDATE THE FORECAST FOR A SLOWER AND LESS EXTENSIVE BREAKOUT TODAY AND TONIGHT. NEXT SYSTEM STILL TIMED INTO THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY BUT WITH THE CURRENT TRACK OF THE LOW AND THE FRONT BECOMING NEGATIVELY TILTED MIGHT HAVE TO SLOW DOWN THE TIMING OF THE SYSTEM IN THE AFTERNOON PACKAGE. UPPER LEVEL RIDGE OVER THE AREA TODAY SLIDING EAST LATER IN THE WEEK WITH MORE SYSTEMS REACHING WESTERN WASHINGTON IN THE SOUTHWESTERLY FLOW ALOFT. FOR NOW WILL JUST UPDATE THE FIRST COUPLE OF PERIODS IN THE ZONES THIS MORNING. FELTON

.LONG TERM...PREVIOUS DISCUSSION FOLLOWS. LOOK FOR AN UNSETTLED WEATHER PATTERN THIS WEAK AS THE MEAN UPPER RIDGE REMAINS OVER THE INTERMOUNTAIN W AND A MEAN TROF CONTINUES OFF THE W COAST. ENERGY ROTATING ACROSS THE AREA AT TIMES WILL KEEP THE WEATHER REGIME SOMEWHAT ACTIVE.

&&

.AVIATION...AIR MASS DOESN`T CHANGE MUCH OVER THE NEXT 24 HOURS...LOW LEVEL MOISTURE FOR FOG AND STRATUS...AND SOME MID AND HIGH CLOUDS. NOT MUCH MOISTURE FROM 2000 TO 12000 FEET HOWEVER. LIGHT GRADIENTS. MORE OF THE SAME A GOOD FCST.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...NONE.

$$

WEATHER.GOV/SEATTLE