Forecast Discussions mentioning "ACARS", "MDCRS", "AIRCRAFT", "TAMDAR", or "AMDAR" received at FSL on 03/19/07

AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1100 PM CDT SUN MAR 18 2007 .DISCUSSION REGARDING AFTERNOON ZONES/GRIDS... 230 PM CDT MODELS RMN IN REASONABLY GOOD AGREEMENT THRU 84 HRS AND AGAIN HAVE MADE LTL CHG TO GOING FCST. ONLY SIG ADJUSTMENT HAS BEEN TO RAISE TEMPS...ESPECIALLY MIN TEMPS...MID-LATE WEEK AS PER MODEL TRENDS AND COORD WITH ADJACENT WFO. NR TERM...WILL CONTINUE WITH FCST OF INCRS IN CLOUD COVER THIS EVENING WITH PCPN DVLPG ARND MIDNIGHT OR SHORTLY THEREAFTER. SATLT TRENDS SHOW BANDS OF ACCAS INCRSG IN COVG ACROSS WRN IA/NRN MO IN RESPONSE TO MID LVL WAA AHEAD OF APCHG SHORT WV NOW MOVG INTO WRN DAKS. MEANWHILE...CU FIELD FROM NRN OK-SRN AR HAS BEEN DVLPG NWD AS MID 50 DEG DEW POINTS GET DRAWN NWD IN RESPONSE TO PRES FALLS OVR NRN/CNTRL PLAINS STAS. BASED ON THESE INDICATIONS...WILL FAVOR CATEGORICAL NAM POPS. FCST SOUNDINGS STILL SUGGEST MAINLY A LIQUID EVENT...BUT THERE WILL LIKELY BE SOME SNOW/SLEET MIXED IN AT ONSET AS COLUMN SATURATES AND INITIALLY COOLS TO WET BULB. EXPECT TO SEE MIN TEMPS AT ONSET OF PCPN WITH SFC THEN WARMING OVERNIGHT IN FACE OF STG LLVL WAA. (H85 TEMPS FCST TO INCR 9 C DEG FROM 00Z-12Z TNGT) MAIN PCPN EVENT TO OCCUR IN 06-12Z TIME FRAME...WITH BEST LLVL FORCING ALREADY E OF FA BY 12Z. HOWEVER...WITH MILD AMS IN PLACE AT START OF PERIOD AND COLD FROPA DUE IN BY NOON...WILL KEEP PCPN MENTION IN THRU MON MRNG. SYS TO N QUITE PROGRESSINVE WITH DECENT AMT OF DOWNWARD MOMENTUM BHD FRONT SO WILL CONTINUE WITH CLRG TREND MON AFTN-ERLY EVENING. HI PRES FCST TO BUILD AS IT PASSES N OF GRTLKS MON NGT-TUES. THERE MAY BE SOME CLOUDS OFF LK MI EFFECTING NERN IL/EXTREME NWRN IND LATE MON NGT INTO TUES MRNG...BUT OVERALL WILL GO WITH CLR CONDS. DESPITE AMPLE SUNSHINE...WILL KEEP MAX`S ON THE COOL SIDE DUE TO NE-E WINDS OFF GRTLKS. ADVERTISED MAJOR PATTERN CHANGE STILL ON TRACK MIDWEEK HOWEVER...AS TROF MOVES INTO WEST COAST...INDUCING UPPER RIDGE ACROSS ERN CONUS THRU WEEKS END. STG WAA SETS UP WITH THIS PATN SHIFT TUES NGT INTO WED. MODELS SEEM TO BE FOCUSING ON WED MRNG-ERLY AFTN AS PERIOD OF GREATER LIKELIHOOD OF SHWRS/TSTMS AS INITIAL THETA-E CONVERGENCE. FCST SOUNDINGS SHOW STGST WAA ARND 900 MB DURG THIS PERIOD...WITH TOTALS INCRSG TO ABV 50. THIS SHOULD SUPPORT THUNDER AS CURRENTLY FCST. SLY FLOW BECOMES ESTABLISHED AND WARM FRONT LIFTS NORTH THRU FCST AREA BY WED EVENING. BASED ON THIS HAVE INCREASED TEMPS/DEW POINTS WEDNGT/THU NGT. THIS PATN BRINGS ABOUT SPRINGLIKE TEMPS (ALMOST ON CUE WITH EQUINOX) AND GREATER PCPN POTENTIAL THRU LATE WEEK AS BROAD SLY LLVL FLOW STREAMS NORTH FROM THE WESTERN GLFMEX. RECENT GLOBAL MODEL RUNS HAVE BEEN CONSISTENT IN HAVING A LOW AMPLITUDE-POSITIVELY SHEARED TROF PROPAGATING THRU MAIN BRANCH OF WLYS THRU SRN CAN...AND A CUTOFF LOW DVLPG ACROSS THE SWRN CONUS THRU SAT. THIS FAVORS SLOWER MOVEMENT OF BAROCLINIC ZONE ACROSS MS VLY/MIDWEST. LATEST GFS THEN BRINGS A MORE DYNAMIC SYS INTO NWRN U.S. NXT WEEKEND WHICH EJECTS SWRN CUTOFF LOW NEWD INTO CNTRL PLAINS. BASED ON THESE TRENDS HAVE A HARD TIME FOCUSING ON SPECIFIC TIMING OF ANY PCPN EMBEDDED WITHIN MILD/MOIST FLOW. THEREFORE HAVE KEPT CHC POPS IN FOR SHWRS/TSTMS THRU AT LEAST SAT. MERZLOCK && .AVIATION... 1100 PM CDT THE WARM AIR HAS MOVED IN THE TAF AREA FASTER THAN PREVIOUSLY ANTICIPATED. THE ACARS SOUNDING AT ORD SHOWS THE AIR BELOW 852 METERS LEVEL IS ABOVE FREEZING. THE NEW LOCALLY RUN WRF ARW SHOWS THIS DEPTH OF AIR ABOVE FREEZING TO CLIMB TO 2277 METERS BY 09 UTC. WE CHANGE OUR PRECIPITATION TO RAIN AFTER 06 UTC. THE RADAR SHOWS SOME ECHOES FROM 8000 FEET TO 13000 FEET IN NORTHEAST ILLINOIS. THE SOUNDING AT DVN AT 00 UTC SHOWS THE SATURATED LAYER ABOVE 7905 FT. THERE IS MORE MOISTURE IN THE ATMOSPHERE. THERE HAVE BEEN SOME VERY LIGHT FLURRIES AROUND THE AREA THIS EVENING. WHEN THE MAIN AREA OF PRECIPITATION MOVES IN IT WILL BE MOSTLY RAIN. THE WIND WILL INCREASE IN SPEED SO WE DO NOT EXPECT ANY IFR VISIBILITY. THE CEILING WILL DECREASE TO MVFR CONDITIONS WITH THE LOWEST 1200 BROKEN TO OVERCAST MONDAY MORNING. THE PRECIPITATION IS FORECAST TO END AFTER 1700 UTC WITH THE WIND SHIFT TO THE NORTHWEST AND DRIER AIR MOVING INTO THE TAF AREA. WE USED THE LOCALLY RUN WRF ARW AND WRF MODEL AT NCEP FOR THE SOUNDING FORECASTS AND WIND FORECASTS. && .LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
709 PM CDT SUN MAR 18 2007 .DISCUSSION REGARDING AFTERNOON ZONES/GRIDS... 230 PM CDT MODELS RMN IN REASONABLY GOOD AGREEMENT THRU 84 HRS AND AGAIN HAVE MADE LTL CHG TO GOING FCST. ONLY SIG ADJUSTMENT HAS BEEN TO RAISE TEMPS...ESPECIALLY MIN TEMPS...MID-LATE WEEK AS PER MODEL TRENDS AND COORD WITH ADJACENT WFO. NR TERM...WILL CONTINUE WITH FCST OF INCRS IN CLOUD COVER THIS EVENING WITH PCPN DVLPG ARND MIDNIGHT OR SHORTLY THEREAFTER. SATLT TRENDS SHOW BANDS OF ACCAS INCRSG IN COVG ACROSS WRN IA/NRN MO IN RESPONSE TO MID LVL WAA AHEAD OF APCHG SHORT WV NOW MOVG INTO WRN DAKS. MEANWHILE...CU FIELD FROM NRN OK-SRN AR HAS BEEN DVLPG NWD AS MID 50 DEG DEW POINTS GET DRAWN NWD IN RESPONSE TO PRES FALLS OVR NRN/CNTRL PLAINS STAS. BASED ON THESE INDICATIONS...WILL FAVOR CATEGORICAL NAM POPS. FCST SOUNDINGS STILL SUGGEST MAINLY A LIQUID EVENT...BUT THERE WILL LIKELY BE SOME SNOW/SLEET MIXED IN AT ONSET AS COLUMN SATURATES AND INITIALLY COOLS TO WET BULB. EXPECT TO SEE MIN TEMPS AT ONSET OF PCPN WITH SFC THEN WARMING OVERNIGHT IN FACE OF STG LLVL WAA. (H85 TEMPS FCST TO INCR 9 C DEG FROM 00Z-12Z TNGT) MAIN PCPN EVENT TO OCCUR IN 06-12Z TIME FRAME...WITH BEST LLVL FORCING ALREADY E OF FA BY 12Z. HOWEVER...WITH MILD AMS IN PLACE AT START OF PERIOD AND COLD FROPA DUE IN BY NOON...WILL KEEP PCPN MENTION IN THRU MON MRNG. SYS TO N QUITE PROGRESSINVE WITH DECENT AMT OF DOWNWARD MOMENTUM BHD FRONT SO WILL CONTINUE WITH CLRG TREND MON AFTN-ERLY EVENING. HI PRES FCST TO BUILD AS IT PASSES N OF GRTLKS MON NGT-TUES. THERE MAY BE SOME CLOUDS OFF LK MI EFFECTING NERN IL/EXTREME NWRN IND LATE MON NGT INTO TUES MRNG...BUT OVERALL WILL GO WITH CLR CONDS. DESPITE AMPLE SUNSHINE...WILL KEEP MAX`S ON THE COOL SIDE DUE TO NE-E WINDS OFF GRTLKS. ADVERTISED MAJOR PATTERN CHANGE STILL ON TRACK MIDWEEK HOWEVER...AS TROF MOVES INTO WEST COAST...INDUCING UPPER RIDGE ACROSS ERN CONUS THRU WEEKS END. STG WAA SETS UP WITH THIS PATN SHIFT TUES NGT INTO WED. MODELS SEEM TO BE FOCUSING ON WED MRNG-ERLY AFTN AS PERIOD OF GREATER LIKELIHOOD OF SHWRS/TSTMS AS INITIAL THETA-E CONVERGENCE. FCST SOUNDINGS SHOW STGST WAA ARND 900 MB DURG THIS PERIOD...WITH TOTALS INCRSG TO ABV 50. THIS SHOULD SUPPORT THUNDER AS CURRENTLY FCST. SLY FLOW BECOMES ESTABLISHED AND WARM FRONT LIFTS NORTH THRU FCST AREA BY WED EVENING. BASED ON THIS HAVE INCREASED TEMPS/DEW POINTS WEDNGT/THU NGT. THIS PATN BRINGS ABOUT SPRINGLIKE TEMPS (ALMOST ON CUE WITH EQUINOX) AND GREATER PCPN POTENTIAL THRU LATE WEEK AS BROAD SLY LLVL FLOW STREAMS NORTH FROM THE WESTERN GLFMEX. RECENT GLOBAL MODEL RUNS HAVE BEEN CONSISTENT IN HAVING A LOW AMPLITUDE-POSITIVELY SHEARED TROF PROPAGATING THRU MAIN BRANCH OF WLYS THRU SRN CAN...AND A CUTOFF LOW DVLPG ACROSS THE SWRN CONUS THRU SAT. THIS FAVORS SLOWER MOVEMENT OF BAROCLINIC ZONE ACROSS MS VLY/MIDWEST. LATEST GFS THEN BRINGS A MORE DYNAMIC SYS INTO NWRN U.S. NXT WEEKEND WHICH EJECTS SWRN CUTOFF LOW NEWD INTO CNTRL PLAINS. BASED ON THESE TRENDS HAVE A HARD TIME FOCUSING ON SPECIFIC TIMING OF ANY PCPN EMBEDDED WITHIN MILD/MOIST FLOW. THEREFORE HAVE KEPT CHC POPS IN FOR SHWRS/TSTMS THRU AT LEAST SAT. MERZLOCK && .AVIATION... 709 PM CDT THE ACARS SOUNDING SHOW THE TEMPERATURE BELOW FREEZING ABOVE 700 METERS AT ORD. THE PRECIPITATION WHEN IT MOVES INTO THE AREA MAY BEGIN AS SNOW OR ICE PELLETS. THE AIR IS DRY FROM THE NEAR SURFACE UP TO 600 MB. THERE ARE LOW DEWPOINTS. THE ISENTROPIC LIFT OF AIR OVER THE REGION TONIGHT WILL INCREASE THE MOISTURE IN THIS LAYER BY 0700 UTC. THE TEMPERATURES THROUGH THE LAYER WILL BE BELOW FREEZING AT FIRST. THEN THE TEMPERATURE WILL INCREASE FROM THE SURFACE TO AROUND 2500 METERS. THIS IS EXPECTED AROUND 09 UTC. THE PRECIPITATION WILL BE RAIN THEN. THE WIND WILL INCREASE IN SPEED SO WE DO NOT EXPECT ANY IFR VISIBILITY. THE CEILING WILL DECREASE TO MVFR CONDITIONS WITH THE LOWEST 1200 BROKEN TO OVERCAST MONDAY MORNING. THE PRECIPITATION IS FORECAST TO END AFTER 1700 UTC WITH THE WIND SHIFT TO THE NORTHWEST AND DRIER AIR MOVING INTO THE TAF AREA. WE USED THE LOCALLY RUN WRF ARW AND WRF MODEL AT NCEP FOR THE SOUNDING FORECASTS AND WIND FORECASTS. && .LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
258 PM CDT SUN MAR 18 2007 .DISCUSSION... DAYS 1-2... THE BIG CHALLENGES FOR THE EARLY PERIODS OF THE FORECAST TODAY ARE ANTICIPATING EXTENT OF PRECIPITATION MONDAY NIGHT INTO TUESDAY IN RESPONSE TO ISENTROPIC LIFT AND UVV IN ADVANCE OF UPPER LEVEL TROUGHS EMBEDDED IN THE SOUTHERN BRANCH OF THE WESTERLIES AS THEY LIFT OVER THE CENTRAL UNITED STATES. TEMPERATURES ALSO ARE A CHALLENGE...ESPECIALLY MONDAY NIGHT INTO TUESDAY. WIDESPREAD STRATIFORM CLOUDINESS AND PRECIPITATION MAY SERVE TO KEEP TEMPERATURES EVEN COOLER THAN REFLECTED IN THE GRIDS ON TUESDAY. THE UPPER LEVEL FLOW REGIME OVER THE UNITED STATES IS IN A RETROGRESSIVE TRANSITION PERIOD BETWEEN A MEAN PATTERN CHARACTERIZED BY RIDGING OVER THE WESTERN PART OF THE CONTINENT AND A PATTERN CHARACTERIZED BY MEAN TROUGHING OVER THE CENTRAL PART OF THE COUNTRY. THE NUMERICAL GUIDANCE TYPICALLY EXHIBITS LOW SKILL DURING THESE PERIODS...AND THE MODELS HAVE BEEN STRUGGLING WITH THE UPPER LEVEL TROUGH CURRENTLY BETWEEN 140W AND 150W AS IT ENTERS THE UNITED STATES BY MID WEEK. ATMOSPHERIC RELATIVE ANGULAR MOMENTUM IS ANOMALOUSLY LOW...AND WIDESPREAD EASTERLY ANOMALIES ARE EVIDENT IN WIND FIELDS OVER THE TROPICS. THIS PATTERN WOULD FAVOR DEVELOPMENT OF SLOW MOVING CLOSED CYCLONES IN THE LOWER LATITUDES...AND ALL OF THE MODELS ARE SUGGESTING THIS EVOLUTION OVER THE SOUTHWESTERN UNITED STATES. THE POTENTIAL EXISTS FOR WIDESPREAD HEAVY RAINFALL IN THE CENTRAL AND SOUTHERN PLAINS AS THE UPPER LEVEL CYCLONE WALLOWS SLOWLY EASTWARD THROUGH THE LATTER PORTION OF THE WEEK. THE MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE FIRST THREE DAYS WITH SOME DISAGREEMENT IN THE EXTENDED PERIOD. THE GFS APPEARED TO INITIALIZE FAIRLY WELL WITH AIRCRAFT AND SATELLITE OBSERVATIONS OVER THE EASTERN PACIFIC AND IS IN FAIRLY GOOD AGREEMENT WITH THE ECMWF AND SEVERAL OF THE CANADIAN ENSEMBLE MEMBERS. AS SUCH, THE GFS LARGELY WAS USED FOR GRID ADJUSTMENTS. THE EXTREMELY WARM AIR COVERING THE CENTRAL PLAINS TODAY WILL BE SUPPRESSED SOUTHWARD TONIGHT AS A PACIFIC COLD FRONT DROPS SOUTHWARD ACROSS KANSAS. A REINFORCING SHOT OF CANADIAN AIR WILL DROP INTO THE NORTHERN UNITED STATES AS A VIGOROUS UPPER LEVEL TROUGH RIPPLES FROM NORTHERN ALBERTA INTO ONTARIO BY MONDAY MORNING...AND A SMALL PORTION OF THE CANADIAN AIR MASS WILL INVADE NORTHERN KANSAS DURING THE DAY MONDAY. EVEN WITH COLD AIR ADVECTION MONDAY...TEMPERATURES SHOULD RISE INTO THE 60S IN MOST AREAS. STRATUS WILL DEVELOP AS THE COLD FRONT ENCOUNTERS INCREASINGLY DEEP LOW LEVEL MOISTURE ACROSS SOUTH CENTRAL KANSAS TONIGHT...AND THE STRATUS WILL BE SLOW TO ERODE DURING THE DAY MONDAY. THE COLD FRONT WILL BECOME STATIONARY ACROSS CENTRAL OKLAHOMA MONDAY EVENING. THE UPPER LEVEL TROUGH EVIDENT IN SATELLITE IMAGERY OVER SOUTHERN CALIFORNIA WILL APPROACH THE CENTRAL PLAINS TUESDAY MORNING...AND THE REMNANTS OF THE UPPER LEVEL LOW PRESSURE SYSTEM CURRENTLY AROUND 28N 135W WILL APPROACH THE CENTRAL PLAINS DURING THE DAY TUESDAY. LOWERING PRESSURES IN ADVANCE OF THE UPPER LEVEL TROUGHS WILL INCREASE SOUTHERLY LOW LEVEL FLOW OVER THE STATIONARY FRONTAL BOUNDARY...AND ABUNDANT LOW LEVEL MOISTURE WILL SPREAD NORTHWARD OVER THE COLD DOME OF AIR ENTRENCHED OVER KANSAS. STRATUS WILL BECOME WIDESPREAD OVER WESTERN KANSAS MONDAY NIGHT...AND AREAS OF LIGHT DRIZZLE AND FOG CAN BE EXPECTED TO DEVELOP LATE MONDAY NIGHT INTO TUESDAY AS THE WARM FRONT STARTS TO OOZE NORTHWARD. SUFFICIENT MID LEVEL INSTABILITY EXISTS TO SUPPORT SHOWER AND THUNDERSTORM DEVELOPMENT IN THE REGION OF ISENTROPIC LIFTING MONDAY NIGHT INTO TUESDAY. CLOUDY SKIES AND WIDESPREAD PRECIPITATION WILL KEEP TEMPERATURES ON THE LOW SIDE TUESDAY...AND TEMPERATURES MAY NOT RISE OUT OF THE UPPER 40S IN THE NORTHERN ZONES. DAYS 3-7... MODELS CONTINUE TO FLIP FLOP ALL OVER THE PLACE IN THE EXTENDED PERIOD. MINOR DIFFERENCES NOTED THROUGH 90 HOURS WITH TROF MOVING INTO WEST COAST AND ASSOCIATED S/WVS MOVING ACROSS FA. SHORTLY THEREAFTER, MAJOR CHANGES TAKE PLACE IN EXTENDED FORECAST. BIG QUESTION REMAINS JUST WHERE WITH THE H5 SOUTHWEST LOW GO. GFS/CANADIAN MODEL ON SIMILAR PAGE THROUGH FRI WHEN GFS DIVES LOW SOUTH INTO THE BAJA. CANADIAN MODEL TAKES SYSTEM TOWARD CO/NM BORDER BY 12Z FRI. ECMWF IS A BIT SLOWER WITH MOVING UPPER LOW OVER NM BUT IT FOLLOWS THE TREND OF THE CANADIAN. THE UKMET SPLITS THE DIFFERENCE. THE CANADIAN ENSEMBLE MEMBERS ARE HOLDING ON TO THE SLOWER/FURTHER SOUTHWEST SOLUTION INITIALLY. FOR NOW, WILL PLAY THE SLOWER SOLUTION OF THE ENSEMBLE CANADIAN/GFS WITH A SOLUTION NOT AS FAR SOUTH. WITH TROF DEVELOPING IN THE WEST, SOUTHWEST KANSAS WILL START TO SEE A MORE ACTIVE PATTERN IN THE EXTENDED FORECAST PERIOD. MONDAYS SYSTEM WILL CONTINUE TO KEEP A FRONTAL BOUNDARY ACROSS SOUTHERN KS/NORTHERN OK WITH PLENTY OF ISENTROPIC LIFT OVER WARM FRONT USHERING MOISTURE ACROSS CWA INTO TUESDAY NIGHT/WEDNESDAY. 305K SPECIFIC HUMIDITIES RANGE FROM +4 G/KG TO +7 G/KG WITH 25KT TO 35KT WINDS THROUGH EARLY WEDNESDAY. SUBTROPICAL BRANCH OF JET STREAM ALSO NOSES TOWARD FA TOWARD WEDNESDAY MORNING. NEXT SYSTEM FORECAST TO DEVELOP IN LEE OF ROCKIES TUESDAY INTO WEDNESDAY BEFORE COMING OUT WEDNESDAY NIGHT/THURSDAY. H85 LLJ IN EXCESS OF +30KTS WITH H85 DEWPOINTS +10C ACROSS EASTERN HALF OF CWA. STRONG INDICATIONS OF DEVELOPING DRYLINE WEDNESDAY AFTERNOON WITH NEAR 60F DEWPOINTS ACROSS EASTERN FA BY AFTERNOON WHILE WESTERN FA WILL ONLY SEE DEWPOINTS INTO THE 30S. IN ADDITION, AT H3, A 70KT+ JET STREAK WILL MOVE INTO WESTERN FA BY EARLY AFTERNOON. LIS ARE FORECAST TO BE WELL BELOW 0C, SOME CAPE IS PRESENT AND PLENTY OF WIND SHEAR PRESENT. IN ADDITION, MID LEVEL LAPSE RATES RANGE FROM 6.5 C/KM TO 8 C/KM. SEVERE WEATHER THREAT CONTINUES TO LOOK POSSIBLE WEDNESDAY AFTERNOON INTO EVENING ACROSS PORTIONS OF SOUTHWEST KS. HAVE LITTLE CONFIDENCE THURSDAY THROUGH WEEKEND WITH MODEL DIFFERENCES OF H5 UPPER SYSTEM. DO THINK THAT WITH UPPER SYSTEM LINGERING ACROSS SOUTHWESTERN US, A WET PATTERN WILL CONTINUE. TO WHAT EXTENT IS STILL IN QUESTION. WILL GO AHEAD AND BUMP UP POPS A BIT THURSDAY ACROSS EASTERN FA GIVEN SLOWER PROGRESSION OF LOW ANTICIPATED. TIMING OF FRONT MOVING ACROSS THE CWA WILL CREATE A BIT OF HAVOC TO ONGOING FORECAST FOR ALL ELEMENTS. FOR NOW, HAVE ONLY MADE MINOR ADJUSTMENTS GIVEN 12Z GFS RUN PROVIDED NO ADDITIONAL CLARITY TO PRESENT DILEMMA. THE NEW RUN HAS ONLY LEFT MORE CHALLENGES AS SOLUTION IS MUCH WETTER THIS TIME AROUND. && .AVIATION... DISCUSSION FOR THE 18Z TAFS. WINDS WILL CONTINUE TO FLOW FROM THE SOUTH THIS AFTERNOON FROM AROUND 15KTS TO 20KTS IN ADVANCE OF A DEVELOPING LOW PRESSURE SYSTEM NEAR THE LEE OF THE ROCKIES. AS THE SYSTEM BEGINS TO MOVE SOUTHEAST OVERNIGHT TONIGHT, IT WILL DRAG A COLD FRONT THROUGH SOUTHWEST KANSAS. BETWEEN 09Z AND 12Z MON, WINDS WILL SHIFT TO A MORE NORTHEASTERLY DIRECTION AS FRONT MOVES ACROSS HYS/GCK. DDC CAN EXPECT WINDS TO BECOME NORTHEAST AROUND 12Z MON. GUSTY WINDS FROM 25 TO 30KTS ARE NOT OUT OF THE QUESTION DURING THE MORNING MON. ONLY SCATTERED CIRRUS CLOUDS ARE EXPECTED THROUGH TAF PERIOD. VFR CONDITIONS WILL PREVAIL THROUGH TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 47 65 43 55 / 0 0 40 50 GCK 45 63 41 54 / 0 0 40 40 EHA 47 67 43 60 / 0 0 30 30 LBL 49 67 45 58 / 0 0 40 40 HYS 45 61 37 52 / 0 0 30 50 P28 54 64 47 59 / 0 10 50 60 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ FN01/30/30
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1140 AM CDT SUN MAR 18 2007 .DISCUSSION... STRONG PREFRONTAL GRADIENT IN PLACE OVR CWA...AND PRIMARY CHANGE TO SHORT TERM TODAY WAS TO BOOST WNDS. MISSING OAX RAOB/NLG PROFILER THIS MORNING...BUT LONE TAMDAR SOUNDING NR KOMA... ABR RAOB...WDL PROFILER...AND FSD VWP SUGGEST THAT THE WINDS ALFT IN MDLS ARE TRULY THERE. WNDS GUSTING TO ARND 40 MPH EARLIER AT KSFD. SHUD REMAIN ON WK SIDE OF ADVISORY AS MAIN PRESSURE FALLS SHIFT EWRD ALG NRN MN/SWRN ONTARIO. OTHERWISE...NICE WARM PLUME ALFT ON WRN PLAINS RAOBS...AND RECENTLY HEATED OUT TO DOWNSLOPED 70 AT KRAP. KICKED TMPS UP A COUPLE DEGREES SEVERAL AREAS AS WELL...ESPLY W... BUT HAD TO ADJUST MOST AREAS TO A MORE RESTRAINED MORNING CLIMB...AND EXPECT SOME QUICK INCREASES IN THE FIRST COUPLE HOURS THIS AFTN. HYDROWISE...ALMOST ALL MAINSTEM RIVER LOCATIONS CRESTED AND WELL INTO FALL. ICE GENERALLY CLEAR...BUT REPORTS FROM JACKSON COUNTY INDICATE THAT ICE MAY PRESENT DAMMING THREAT ALG THE WEST FORK OF DES MOINES RIVER AT LEAST THRU TDA. && .PREV DISCUSSION... UPPER RIDGE WILL SLIDE EAST ACROSS THE REGION TODAY WHILE FLATTENING AS SHORTWAVE CURRENTLY OVER NRN ID PASSES THROUGH THE RIDGE. EASTWARD PROGRESSION OF THE RIDGE WILL TAKE WITH IT ANY CHANCES OF PRECIPITATION TODAY SO REMOVED POPS THIS MORNING. REGION RADAR MOSAIC INDICATES SOME VIRGA INTO NE SD AND ERN ND...BUT EVEN THIS IS BEGINNING TO DIMINISH. ISENTROPIC LIFT IS LESS THAN IMPRESSIVE WITH BEST LIFT MOVING INTO CNTRL AND ERN MN THIS MORNING. MAIN CHALLENGE TODAY IS TEMPERATURES...AS THERE WILL BE A DECENT GRADIENT ACROSS THE CWA. WARM AIR WILL ADVECT EAST AS WILL MAIN CLOUD DECK...SO GENERALLY PARTLY CLOUDY SKIES WILL ALLOW FOR SOME MIXING BUT PROBABLY NOT TO THE FULL EXTEND IN MOST PLACES AND SFC WINDS WILL REMAIN SRLY. COULD SEE SOME 70S IN THE WEST THIS AFTERNOON DEPENDING ON TIMING OF SFC TROUGH AND WRLY WINDS. PREVIOUSLY MENTIONED SW/V WILL DROP ACROSS SW MN THIS EVENING...HOWEVER MIDLEVELS CONTINUE TO LOOK DRY. CAN NOT IMAGINE ANYTHING MORE THAN A FEW SPRINKLES MAKING IT TO THE SFC...SO LEFT POPS BELOW SLIGHT CHANCE AS MEASURABLE PRECIP WILL BE LOW. COLD FRONT WILL PASS OVERNIGHT...ONCE AGAIN BRINGING COOLER TEMPERATURES TO THE AREA ON MON...BUT STILL CLOSE TO NORMAL FOR THIS TIME OF YEAR. PLENTY OF MIXING WITH FROPA TONIGHT...SO WENT WITH TEMPERATURES SLIGHTLY ABOVE GUIDANCE...MAINLY IN THE 30S. WARMER AIR WILL BEGIN TO RETURN MON NIGHT AS UPPER RIDGE REBOUNDS AHEAD OF A DEVELOPING TROUGH OVER THE WRN CONUS. THIS TROUGH WILL BE THE NEXT POTENTIAL WEATHER MAKER FOR THE AREA. MODELS SEEM TO BE HAVING A TOUGH TIME DETERMINING WHETHER THE NRN OR SRN STREAM WILL DOMINATE OUR WEATHER MID WEEK. MODELS HAVE BEEN TRENDING MORE TOWARD THE NRN STREAM...WHICH MEANS LESS CHANCE OF PRECIPITATION...ESPECIALLY IN THE WRN CWA. DID NOT MAKE MUCH OF A CHANGE IN POPS AS OF YET...HOWEVER WILL BE TOUGH TO PRODUCE MUCH IN THE WAY IN MEASURABLE MOISTURE WITHOUT UPPER ENERGY FROM SRN WAVE...WHICH MORE AND MORE APPEARS IF IT WILL BECOME CUT OFF. STILL...A LOT OF LOW LEVEL MOISTURE WILL LIKELY STREAM NORTH AHEAD OF THE TROUGH...BUT AT FIRST WOULD LIKELY ONLY BE GOOD IN CREATING STRATUS MAYBE DRIZZLE...SO LOWER POPS WED/WED NIGHT...PROBABLY NOT ENOUGH. ALSO WOULD BE TOUGH TO PRODUCE THUNDER WITH LITTLE ISENTROPIC FORCING AND DRY MIDLEVELS...FOR NOW LEFT A MENTION OF ISOLATED THUNDER. BEST CHANCE FOR THUNDERSTORMS WOULD LIKELY NOT BE UNTIL LATE THU AND MIDLEVEL BNDRY SHIFTS EAST...PROVIDED SOME SRN STREAM ENERGY COMES N. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ CHAPMAN/LIEBL
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
315 AM PDT MON MAR 19 2007 .SHORT TERM... 08Z ACARS SOUNDING PLACES THE MARINE LAYER AT 2950 FEET. CURRENT DAG GRADIENT IS 6.9 ON ITS WAY TO A FORECAST VALUE OF +8.8MB AT 00Z THIS AFTERNOON WHICH IF TRUE WILL BE THE HIGHEST VALUE EVER RECORDED IN MARCH DURING THE 21ST CENTURY. THE WEATHER TODAY WILL BE MUCH LIKE SUNDAY WITH LITTLE OR NO CLEARING OVER THE COASTS SOUTH OF POINT CONCEPTION AND SOME BUT NOT TOTAL CLEARING OVER THE VALLEYS. THIS WILL SPARK GOOD WINDS IN THE ANTELOPE VALLEY AGAIN. CLOSE TO WIND ADVISORY CRITERIA BUT OT QUITE. THE MARINE LAYER WILL REFORM SOUTH OF POINT CONCEPTION TONIGHT AND WITH THE APPROACHING TROF SOME DRIZZLE MAY FALL ESP NEAR THE FOOTHILLS. NO THREAT OF ACTUAL RAIN TONIGHT AS TROF WILL HOLD OFF. WHERE THERE IS NOT A MARINE LAYER MID AND HIGH CLOUDS WILL INCREASE. TUESDAY WILL BE CLOUDY AND COOL. RAIN IS ANOTHER QUESTION. THE SYSTEM IS WHOLLY UNIMPRESSIVE. LIMITED LOW LEVEL MOISTURE...ZERO SOUTH FLOW AND SCARCE DYNAMICS. AS ALWAYS THE BEST CHANCE OF RAIN WILL BE OVER THE CENTRAL COAST. THE TROF IS SHOWING SOME SIGNS OF SLOWING SO CARRIED POPS INTO WED MORNING. AT THIS TIME IT LOOKS LIKE THE BEST CHANCE OF RAIN WILL BE ON THE NORTH SLOPES TUESDAY NIGHT. A QUARTER INCH OF RAIN IS THE MOST THIS SYSTEM WILL PRODUCE AND MOST PLACES WILL RECEIVE MUCH LESS. A FAIRLY GOOD NORTH WIND EVENT WILL SET UP TUESDAY NIGHT THE I-5 CORRIDOR WILL BE AFFECTED BY THESE WINDS WHICH WILL BE NEAR ADVISORY CRITERIA. WEDNESDAY WILL BE COOL. CLOUDS WILL BE ON THE DECREASE. TEMPS WILL STILL BE BELOW NORMAL WITH ONLY 560DM HGTS OVERHEAD. .LONG TERM... A NICE LITTLE OFFSHORE EVENT IS SHAPING UP THURSDAY AS A CUT OFF LOW SW OF SAN DIEGO WILL PULL THE UPPER FLOW OFFSHORE TO COMPLEMENT THE BUILDING OFFSHORE SURFACE PRESSURE TREND. RIGHT NOW IT LOOKS LIKE IT WILL COME IN AT LESS THE WAD STRENGTH BUT THE MDLS HAVE BEEN TRENDING IT STRONGER WITH EACH RUN. A WEAK RIDGE WILL BUILD IN OVER THE AREA FRIDAY THROUGH NEXT SUNDAY AND THE WEATHER WILL BE PLEASANT IF A LITTLE DULL. TEMPS WILL RISE TO NEAR NORMAL AND MAYBE A DEGREE OR TWO ABOVE NORMS. && .AVIATION... 19/0930 SIMILAR PATTERN TO YESTERDAY AS STRONG ONSHORE GRADIENTS ARE FORECAST ONE AGAIN. MARINE LAYER CURRENTLY 3000 FT THIS MORNING. EXPECT MVFR CIGS AND VFR/MVFR VSBYS MOST AREAS S OF POINT CONCEPTION TODAY. BURNOFF ACROSS THE VALLEYS SHOULD OCCUR BETWEEN 19-20Z WITH MOSTLY CLOUDY CONDITIONS ACROSS THE COASTAL SECTIONS ONCE AGAIN TODAY. EXPECT LOWER CIGS ACROSS THE CENTRAL COAST AND SALINAS VALLEY AS KSMX AND KSBP SHOULD BE IFR CIGS AND MVFR VSBYS THIS MORNING...WITH BURNOFF NEAR COAST BY 20Z. KPRB SHOULD SEE LIFR CIGS EARLY...THEN BECOMING IFR BY 16Z WITH STRATUS BURNOFF BY 18Z WITH VFR CONDITIONS AFTER THAT. SOME AFTERNOON GUSTY WESTERLY WINDS TO 25 KT ACROSS THE ANTELOPE VALLEY. KLAX...A REPEAT OF YESTERDAY WITH MOSTLY CLOUDY SKIES. MOSTLY MVFR CIGS AND VFR VSBYS WILL PREVAIL THROUGH THE AFTERNOON. WINDS SHOULD BE VARIABLE 6 KT OR LESS THROUGH 17Z...BECOMING SW TO W SEABREEZE BY 18Z WITH STRONGEST SUSTAINED WINDS NEAR 12 KT IN THE AFTERNOON AND EVENING HOURS. KBUR...EXPECT MVFR CIGS AND VFR VSBYS UNTIL 20Z. STRATUS BURNOFF WILL LEAD TO PARTLY CLOUDY SKIES DUE TO THE DEEPNESS OF THE MARINE LAYER. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXCWFLOX). && $$ PUBLIC...RORKE AVIATION...KAPLAN WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
351 AM CDT MON MAR 19 2007 .DISCUSSION REGARDING MORNING ZONES/GRIDS... 351 AM CDT MID LVL TROF AMPLIFYING ACROSS UPR MIDWEST/WRN LAKES THIS MORNING...INDUCING SOME SERIOUS LLVL WAA VIA INTO THE REGION WITH REGIONAL PROFILERS DEPICTING 60-70 KT SWLY FLOW IN 925-850 HPA LAYER. ELEVATED LLVL THETA/E AND MOISTURE CONVERGENCE MAXIMA IN AXIS OF MOIST/UNSTABLE AIR COINCIDENT WITH JET TO TRANSLATE QUICKLY EAST ACROSS SERN HALF OF CWA EARLY THIS MORNING...BEFORE MOVG EAST OF FCST AREA LATER THIS MORNING. THEREFORE CURRENT RADAR DEPICTION OF ELEVATED TRW/RW EXPECTED TO PROGRESS ACROSS AND EVENTUALLY E/SE OF FCST AREA THRU 12-15Z. WILL THUS MAINTAIN CATEGORICAL POPS ACROSS SERN PARTS OF FCST AREA THIS MORNING...AND WILL HOLD ONTO CHC POPS FARTHER NORTHWEST AS SFC COLD FRONT AND MAIN MID LVL S/WV TROF AXIS MOVG THRU MIDDAY. PASSAGE OF THESE FEATURES SHOULD ALLOW SOME CLRG THIS AFTN FROM NW TO SE AS SUBSIDENCE AND LLVL DRY ADVECTION INCREASE IN WAKE OF S/WV. SFC HIGH PRESSURE BUILDS THROUGH NRN GRTLKS TNGT...WITH DRY N/NE LLVL FLOW INTO FCST AREA PROVIDING GENERALLY CLR/COOL WX. SOME POTENTIAL FOR SOME LAKE GENERATED STRATOCU AS COLD POOL PASSES ACROSS LAKE MICH OVRNGT...THOUGH FCST SOUNDINGS INDICATE SUBSIDENCE INVERSION PRETTY FORMIDABLE AND THINK PARTLY CLOUDY CONDITIONS AT WORST NEAR THE BIG POND. SFC HIGH MOVES OFF TO THE EAST ON TUESDAY...WITH LLVL WAA DVLPG ESPECIALLY ALONG/WEST OF MS RIVER AS WEAK AMPLITUDE S/WV TROF PUSHES TOWARD UPPER RIDGE FROM THE WEST. TSECTS REMAIN DRY THRU MID/UPR LEVELS AND SUSPECT LITTLE IN THE WAY OF CLOUD COVER. DESPITE STRONG SUN...COOL EASTERLY FLOW TO LIMIT TEMPS ESPECIALLY NRN IL WITH WINDS OFF LK. NEXT SIG WX APPEARS TO DVLP LATE TUES NGT/WED AS WELL ADVERTISED LARGE SCALE UPPER PATERN SHIFT BEGINS. MID LVL S/WV CONTINUES TO PUSH EAST...WITH LLVL WAA RESPONSE STRENGTHENING OVRNGT. WRF/GFS BOTH DVLP 55 KT 850 JET AHEAD OF APPRCHG WAVE...NOT UNLIKE CURRENT SCENARIO THIS MORNING. WHILE GENERAL IDEA VERY SIMILAR BETWEEN MODEL SIMULATIONS...THERE IS BOUT A 6 HOUR TIMING DIFFERENCE WITH POSN OF WAVE WITH GFS THE FASTER SOLN. DIFFERENCE IS FOR GREATEST PCPN PROB LATE TUES NGT OR DURG MORNING HOURS ON WED. ATTM WILL BLEND WITH CHC LATE TUES NGT AND RAISE POPS A BIT WED MORNING. MODELS THEN IN GOOD AGREEMENT IN MOVG THIS MINOR AMPLITUDE S/WV NORTHEAST OF REGION DURG AFTN HOURS AS SFC WARM FRONT LIFTS INTO FCST AREA WITH WARM/MOIST AIR PUMPING NORTH ON BREEZY SOUTH WINDS. ANOTHER S/WV DEPICTED TO WEST ACROSS PLAINS APPEARS TO SHIFT FOCUS FOR HIGHEST PCPN THREAT BACK ACROSS NEB/WRN IA ALONG WRMFRNT...THOUGH WILL MAINTAIN CHC POPS WED AFTN AS CANT RULE OUT POTENTIAL VCNTY WRMFRNT WHICH MOVES TO IL/WI/SRN LK MICH VCNTY BY 00Z. HAVE RAISED TEMPS WELL INTO 60S FOR WED AFTN GIVEN GOOD LLVL THERMAL ADVECTION. MAIN BRANCH OF WESTERLIES AMPLIFIES ACROSS NRN CONUS WED NGT/THURS BRINING COLD FRONT SAGGING INTO FCST AREA ON THURSDAY. BEST POPS APPEAR TO BE DURG THE DAY THURS AT THIS DISTANCE...THOUGH INCREASING POTENTIAL WEST WED NGT AS FRONT/UPPER WAVE APPROACH. GIVEN DIFFICULTIES OF TIMING SMALLER WAVES HAVE MADE LITTLE CHANGE TO BROAD BRUSH POPS IN THESE LATER PERIODS. RATZER && .AVIATION... 1100 PM CDT THE WARM AIR HAS MOVED IN THE TAF AREA FASTER THAN PREVIOUSLY ANTICIPATED. THE ACARS SOUNDING AT ORD SHOWS THE AIR BELOW 852 METERS LEVEL IS ABOVE FREEZING. THE NEW LOCALLY RUN WRF ARW SHOWS THIS DEPTH OF AIR ABOVE FREEZING TO CLIMB TO 2277 METERS BY 09 UTC. WE CHANGE OUR PRECIPITATION TO RAIN AFTER 06 UTC. THE RADAR SHOWS SOME ECHOES FROM 8000 FEET TO 13000 FEET IN NORTHEAST ILLINOIS. THE SOUNDING AT DVN AT 00 UTC SHOWS THE SATURATED LAYER ABOVE 7905 FT. THERE IS MORE MOISTURE IN THE ATMOSPHERE. THERE HAVE BEEN SOME VERY LIGHT FLURRIES AROUND THE AREA THIS EVENING. WHEN THE MAIN AREA OF PRECIPITATION MOVES IN IT WILL BE MOSTLY RAIN. THE WIND WILL INCREASE IN SPEED SO WE DO NOT EXPECT ANY IFR VISIBILITY. THE CEILING WILL DECREASE TO MVFR CONDITIONS WITH THE LOWEST 1200 BROKEN TO OVERCAST MONDAY MORNING. THE PRECIPITATION IS FORECAST TO END AFTER 1700 UTC WITH THE WIND SHIFT TO THE NORTHWEST AND DRIER AIR MOVING INTO THE TAF AREA. WE USED THE LOCALLY RUN WRF ARW AND WRF MODEL AT NCEP FOR THE SOUNDING FORECASTS AND WIND FORECASTS. && .LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...SMALL CRAFT ADVSRY THRU TUES MORN. && $$
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1100 AM PDT MON MAR 19 2007 .SHORT TERM... 16Z AMDAR DATA (ACARS) SHOWS THE DEPTH OF THE MARINE LAYER AT AROUND 3800 FEET. ADD IN A MODERATE TO STRONG ONSHORE PRESSURE GRADIENT FOR KLAX-KDAG AT OVER 5 MB AND ONE WOULD NOT EXPECT TOO MUCH CLEARING OF THE LOW CLOUDS AND FOG THIS AFTERNOON. IN FACT...THE LOW CLOUDS AND FOG ARE CURRENTLY AT THE DOORSTEP OF PALMDALE HAVING NEGOTIATED THEIR WAY THROUGH MUCH OF SOLEDAD CANYON. WOULD NOT BE SURPRISED TO HEAR OF SOME LOCALLY DENSE FOG IN PORTIONS OF SOLEDAD CANYON. ONLY VALLEY SECTIONS ARE LIKELY TO SEE SOME SUNSHINE THIS AFTERNOON. GUSTY WINDS WILL BE RATHER STRONG FOR THE ANTELOPE VALLEY TODAY...PERHAPS A LITTLE STRONGER THAN CURRENTLY FORECAST...THANKS TO THE STRONG ONSHORE FLOW. FOR TONIGHT AND TUESDAY...SOUTHWEST CALIFORNIA CAN EXPECT CONTINUED LOW CLOUDS AND FOG IN THE COASTAL AND VALLEY SECTIONS WHILE THE MOUNTAINS AND DESERTS WILL HAVE MOSTLY CLEAR TO PARTLY CLOUDY SKIES. WITH LOWERING HEIGHTS AS A TROUGH APPROACHES THE FORECAST AREA...EXPECT THE DAYTIME TEMPERATURES TO DROP A FEW DEGREES...THE GREATEST DROP TAKING PLACE IN THE INTERIOR SECTIONS. TUESDAY NIGHT AND WEDNESDAY...A TROUGH IN THE EASTERN PACIFIC WOULD HAVE TO OVERCOME SEVERAL FACTORS TO BRING MUCH RAIN TO THE AREA. THE MODELS SEEM TO BE IN SOME DISAGREEMENT WITH THE GFS MORE FORCEFUL IN BRINGING A DECENT SHOT OF PRECIPITATION TO THE NORTHERN AREAS. THE WRF MODEL SEEMS TO BE INDICATING A WEAKER SYSTEM PERHAPS DUE TO A SPLIT FLOW ALONG THE WEST COAST....LIMITED MOISTURE...AND A LACK OF ANY LOW LEVEL SOUTHERLY FLOW IN ADVANCE OF THE SYSTEM. IN ANY CASE...WILL RAISE THE POPS A BIT FOR SECTIONS NORTH OF POINT CONCEPTION. THE PRECIPITATION WILL AFFECT THE CENTRAL COAST BY LATE AFTERNOON OR EARLY EVENING TUE. ON WEDNESDAY...THE SOUTHERN END OF THE TROUGH EVOLVES INTO A CUTOFF LOW OFF THE SOUTHWEST CALIFORNIA COAST WHICH WILL CONTINUE A SMALL THREAT OF SHOWERS THROUGH WEDNESDAY. WEDNESDAY NIGHT AND THURSDAY...THE UPPER LOW WILL DRIFT SLOWLY TO THE SOUTHEAST DURING THIS PERIOD PLACING THE FORECAST ON THE NORTHERN PERIMETER OF THE CLOSED CIRCULATION. THE EASTERN SAN GABRIEL MOUNTAINS IN LOS ANGELES COUNTY MAY GET SOME WRAP AROUND MOISTURE...OTHERWISE SURFACE HIGH PRESSURE BUILDING OVER THE GREAT BASIN IN ADDITION TO EASTERLY FLOW ALOFT WILL PRODUCE SOM GUSTY OFFSHORE WINDS ON THURSDAY ALONG WITH A DECENT CLEARING TREND. .LONG TERM...FROM PREVIOUS DISCUSSION... A NICE LITTLE OFFSHORE EVENT IS SHAPING UP THURSDAY AS A CUT OFF LOW SW OF SAN DIEGO WILL PULL THE UPPER FLOW OFFSHORE TO COMPLEMENT THE BUILDING OFFSHORE SURFACE PRESSURE TREND. RIGHT NOW IT LOOKS LIKE IT WILL COME IN AT LESS THE WAD STRENGTH BUT THE MDLS HAVE BEEN TRENDING IT STRONGER WITH EACH RUN. A WEAK RIDGE WILL BUILD IN OVER THE AREA FRIDAY THROUGH NEXT SUNDAY AND THE WEATHER WILL BE PLEASANT IF A LITTLE DULL. TEMPS WILL RISE TO NEAR NORMAL AND MAYBE A DEGREE OR TWO ABOVE NORMS. && .AVIATION... 19/1740Z MARINE LAYER HAS PUSHED UP TO ABOUT 3800 FT THIS MORNING...WITH A PERSISTENT EDDY STILL IN PLACE. CLEARING WILL BE SPARSE ONCE AGAIN...BUT MOST CIGS WILL PUSH ABOVE 030 AND VFR BY 20Z. KVNY AND KBUR SHOULD SEE CLEARING NEAR 22Z...BUT MIGHT ACTUALLY OCCUR A BIT BEFORE THAT. KPRB KSBP AND KSMX SHOULD SEE CLEARING BETWEEN 19Z AND 21Z...BUT WILL NOT LAST LONG...WITH MOST OF THOSE AIRFIELDS SEEING MVFR CIGS RETURNING NEAR 03Z. GUSTY WESTERLY WINDS ONCE AGAIN AT KPMD AND KWJF THROUGH ABOUT 03Z...PEAKING AROUND 23Z. KLAX...STRATUS SHOULD REMAIN...BUT SHOULD PUSH INTO VFR ABOVE 030 BY 21Z. CIGS WILL LOWER ONCE AGAIN NEAR 04Z. TYPICAL WESTERLY SEABREEZE NEAR 10 KT EXPECTED THROUGH 03Z OR SO. KBUR...CIGS WILL TEETER NEAR 020 THROUGH ABOUT 20Z. AFTER THAT...SCT-BKN025 CONDITIONS WILL PREVAIL. FAIRLY CONFIDENT THERE WILL BE A BREAK IN THE CIGS BETWEEN 21Z AND 03Z...BUT EXACT TIMING AND WHETHER OR NOT IT WILL BE PERSISTENT OR TEMPO IN NATURE IS UNCERTAIN. HAZE SHOULD LINGER AS WELL...BUT MAY GO UP TO 7SM DURING TIMES OF CLEARING. TYPICAL SOUTHERLY SEABREEZE AFTER 21Z. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXCWFLOX). && $$ PUBLIC...SWEET AVIATION...KITTELL WWW.WEATHER.GOV/LOSANGELES