Forecast Discussions mentioning any of "HRRR" "RR" "RUC13" "RUC" received at GSD on 03/28/12


AREA FORECAST DISCUSSION
NWS CHARLESTON SC
612 PM EDT MON MAR 26 2012 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION LATE TONIGHT AND EARLY THURSDAY...THEN HIGH PRESSURE WILL BUILD SOUTH AND SHIFT INTO THE MID ATLANTIC THROUGH WEDNESDAY. ANOTHER COLD FRONT WILL MOVE THROUGH THURSDAY...FOLLOWED BY ANOTHER AREA OF HIGH PRESSURE BUILDING TO THE NORTH FRIDAY. AN AREA OF UNSETTLED WEATHER WILL APPROACH FROM THE WEST FOR THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... NO MAJOR CHANGES WERE MADE TO THE FORECAST FOR THE EARLY EVENING UPDATE. EXPECT A CLEAR AND TRANQUIL EVENING. A COLD FRONT WILL ADVANCE THROUGH NORTHERN COUNTIES AFTER MIDNIGHT...AND NE WINDS WILL SURGE PERHAPS RESULTING IN SOME UNEVEN TEMPERATURE TRENDS. THE FRONT COULD BE ACCOMPANIED BY A FEW CLOUDS BUT MODEL SOUNDINGS SUGGEST THAT MOSTLY CLEAR FORECASTS ARE REASONABLE. TEMPERATURES WILL BOTTOM OUT IN THE LOWER TO MID 50S AT MOST LOCATIONS. A FEW OF THE COOLEST INLAND LOCATIONS COULD DIP INTO THE UPPER 40S BRIEFLY AROUND DAYBREAK. AT THE COAST...TEMPERATURES COULD FALL INTO THE UPPER 50S/AROUND 60F THIS EVENING...THEN TEMPERATURES COULD ACTUALLY RISE A FEW DEGREES AS AN ONSHORE WIND DEVELOPS LATE. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... TUESDAY...THE DRY COLD FRONT WILL CONTINUE TO PRESS SOUTHWARD TUESDAY MORNING INTO TUESDAY AFTERNOON...RESULTING IN NOTICEABLY COOLER HIGH TEMPERATURES COMPARED TO PREVIOUS DAYS. MODERATE NORTHEAST FLOW BEHIND THE DESCENDING FRONT WILL CREATE A DECENT NORTH/SOUTH TEMPERATURE GRADIENT. EXPECT AFTERNOON TEMPERATURES TO BE SUPPRESSED AROUND 70 DEGREES ACROSS THE NORTHERN FORECAST AREA...WHILE RISING INTO THE UPPER 70S NEAR THE ALTAMAHA RIVER IN SOUTHEAST GEORGIA. SURFACE HIGH PRESSURE WILL SETTLE INTO THE MID ATLANTIC AND SOUTHEAST STATES IN THE WAKE OF THE FRONT BY TUESDAY NIGHT. THE RESULTING WEAK PRESSURE GRADIENT AND LIGHT WINDS WILL ENHANCE RADIATIONAL COOLING UNDER MOSTLY CLEAR SKIES...SUPPORTING MORE SEASONAL LOW TEMPERATURES RANGING FROM THE UPPER 40S NORTH TO THE LOWER 50S SOUTHEAST GEORGIA. WEDNESDAY...SURFACE HIGH PRESSURE WILL CONTINUE TO DESCEND SOUTHWARD AND SLIP OFF THE COAST INTO THE ATLANTIC WATERS ON WEDNESDAY. EXPECT A MORE SOUTHERLY FLOW TO DEVELOP BY THE AFTERNOON HOURS...AND UNDER MOSTLY SUNNY TO PARTLY CLOUDY SKIES...HIGH TEMPERATURES WILL TREND WARMER IN THE UPPER 70S TO LOWER 80S AWAY FROM THE LOCALLY COOLER COASTLINE. LOW TEMPERATURES WILL ALSO MODERATE WEDNESDAY NIGHT WITHIN THE WARMER FLOW AND HIGHER DEWPOINTS. THURSDAY...SHORTWAVE ENERGY AND AN ASSOCIATED SURFACE LOW WILL MOVE FROM THE GREAT LAKES REGION INTO THE NEW ENGLAND STATES WEDNESDAY NIGHT INTO EARLY THURSDAY...PULLING A TRAILING COLD FRONT SOUTHWARD THROUGH THE MID ATLANTIC AND SOUTHEAST STATES LATER IN THE DAY. LATEST NUMERICAL MODEL SOLUTIONS SUGGEST LOW AND MID LEVEL FLOW WILL GENERALLY REMAIN WEST DURING FRONTAL PASSAGE...EVIDENCE THAT THE SYSTEM WILL BE LACKING A DECENT TAP INTO DEEPER MOISTURE. RAIN POTENTIAL THUS APPEARS QUITE LIMITED ON THURSDAY AND PREFER TO KEEP RAIN CHANCES BELOW 15 PERCENT AT THIS POINT. SINCE THE WIND SHIFT ASSOCIATED WITH THE PASSING FRONT WILL BE DELAYED UNTIL THURSDAY EVENING...TEMPERATURES ARE EXPECTED TO WARM INTO THE LOWER 80S AWAY FROM THE COAST WITHIN SOME PRE-FRONTAL COMPRESSION. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... THE WEAK FRONT WILL CONTINUE TO PUSH THROUGH THE AREA FROM NORTH TO SOUTH THURSDAY NIGHT...SETTLING SOUTH OF THE AREA ON FRIDAY. ANOTHER AREA OF HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES. AFTER A WARM-UP MID WEEK...TEMPERATURES WILL COOL DOWN AGAIN BY A FEW DEGREES. RIGHT NOW...THE WEEKEND LOOKS UNSETTLED. AN AREA OF SHORTWAVE ENERGY THAT COMES ASHORE IN SOUTHERN CALIFORNIA MID WEEK WILL WORK ITS WAY ACROSS THE SOUTHERN TIER OF THE U.S. AND APPROACH FROM THE LOWER MISSISSIPPI VALLEY LATER SATURDAY INTO SUNDAY. TIMING AND DETAILS ARE TOO TOUGH TO PIN DOWN THIS FAR OUT...BUT WE WILL DEFINITELY SEE AN INCREASE IN CLOUDS AND CHANCES OF RAIN FOR SATURDAY AFTERNOON INTO SUNDAY...WITH SOME IMPROVING CONDITIONS POSSIBLE BY MONDAY. && .AVIATION /22Z MONDAY THROUGH SATURDAY/... VFR FOR THE NEXT 24 HOURS AT KCHS/KSAV. EXTENDED AVIATION OUTLOOK...THERE ARE NO CONCERNS WITH A GREATER THAN 30 PERCENT CONFIDENCE FACTOR. && .MARINE... INCOMING RUC DATA SUGGESTS THE FRONT AND ITS ACCOMPANYING SURGE WILL ARRIVE ACROSS THE CHARLESTON COUNTY COASTAL WATERS AND THE CHARLESTON HARBOR A FEW HOURS EARLIER THAN EXPECTED. HAVE ADJUSTED THE START TIMES OF THE SMALL CRAFT ADVISORIES FOR THESE ZONES GIVEN THESE TRENDS. NO OTHER CHANGES WERE MADE FOR THE TONIGHT PERIOD. WINDS AND SEAS WILL REMAIN ELEVATED EARLY TUESDAY...AS THE PRESSURE GRADIENT TIGHTENS IN RESPONSE TO BUILDING HIGH PRESSURE BEHIND A DESCENDING COLD FRONT. WILL CONTINUE SMALL CRAFT ADVISORIES FOR THE CHARLESTON HARBOR THROUGH NOON ON TUESDAY...WHILE MAINTAINING ADVISORIES FOR THE NEARSHORE WATERS THROUGH THE AFTERNOON HOURS. A BETTER FETCH OVER THE OUTER GEORGIA WATERS WILL MAINTAIN ADVISORY-LEVEL SEAS THROUGH TUESDAY NIGHT. SURFACE HIGH PRESSURE WILL STEADILY DRIFT SOUTHWARD AND INTO THE ATLANTIC TUESDAY NIGHT THROUGH WEDNESDAY...ALLOWING WINDS AND SEAS TO DIMINISH WITH THE RELAXING PRESSURE GRADIENT. THE GRADIENT WILL THEN INCREASE AGAIN AS A BACKDOOR COLD FRONT DESCENDS TOWARD THE REGION LATE WEDNESDAY INTO THURSDAY. EXPECT WINDS AND SEAS TO RISE ACCORDINGLY...HOWEVER HEADLINES ARE NOT ANTICIPATED AT THIS TIME. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 1 PM EDT TUESDAY FOR AMZ330. SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EDT TUESDAY FOR AMZ352. SMALL CRAFT ADVISORY FROM 1 AM TO 5 PM EDT TUESDAY FOR AMZ350. SMALL CRAFT ADVISORY FROM 7 AM TUESDAY TO 2 AM EDT WEDNESDAY FOR AMZ374. SMALL CRAFT ADVISORY FROM 7 AM TO 5 PM EDT TUESDAY FOR AMZ354. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
516 AM CDT MON MAR 26 2012 .DISCUSSION... 325 AM...WEAK UPPER WAVE SHIFTING SOUTHEAST ACROSS SOUTHERN MN AND SOUTHWEST WI EARLY THIS MORNING WITH AN AREA OF SHOWERS AND A FEW TS. MODELS SEEM CONSISTENT THAT THIS WILL PUSH INTO NORTHWEST IL LATER THIS MORNING. WHILE QPF AMOUNTS WILL BE LIGHT PERHAPS MANY AREAS ONLY SEEING A TRACE...HAVE INCLUDED A CHANCE OF SHOWERS WITH COVERAGE EXPECTED TO DECREASE INTO THE AFTERNOON HRS. DESPITE THE LOW PRECIP CHANCES...APPEARS MOSTLY CLOUDY SKIES WILL PREVAIL THROUGH MUCH OF THE DAY WHICH WILL LIMIT HEATING AS TEMPS ARE NOW FALLING THROUGH THE 40S WITH MANY LOCATIONS ALREADY INTO THE UPPER 30S. STILL EXPECT SOME SUN ACROSS THE SOUTHERN CWA BUT TEMPS ACROSS THE NORTH A BIT TRICKY. OVERALL ONLY TWEAKED THEM LOWER A DEGREE OR TWO BUT THERE IS THE POTENTIAL FOR TEMPS TO BE COOLER THAN CURRENTLY ADVERTISED. FLOW TURNS BACK SOUTHERLY TONIGHT AND COULD BE SOME WARM AIR ADVECTION PRECIP OVERNIGHT INTO EARLY TUESDAY MORNING BUT APPEARS THE BULK OF THIS ACTIVITY WOULD REMAIN NORTH OF THE CWA. BUT SIMILAR TO TODAY/S WAVE...LOOKS LIKE THERE WILL BE PLENTY OF CLOUD COVER AT LEAST ACROSS NORTHERN IL. COULD SEE A QUICK DROP IN TEMPS THIS EVENING AND DEPENDING ON HOW EXTENSIVE CLOUD COVER BECOMES... COULD BE SOME FROST ACROSS THE EASTERN CWA/NORTHWEST INDIANA WHERE LOWS COULD BE IN THE MID 30S. TOO MUCH UNCERTAINTY FOR ANY HEADLINES THIS MORNING AND WILL LET THE DAY SHIFT TAKE A LOOK AT THIS POTENTIAL MORE CLOSELY. LOW PRESSURE WILL LIFT ACROSS THE NORTHERN PLAINS TUESDAY AND ACROSS THE UPPER LAKES TUESDAY NIGHT WITH A TRAILING COLD FRONT SWEEPING ACROSS THE AREA LATE TUESDAY AFTERNOON INTO EARLY WEDNESDAY MORNING. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH MOISTURE POOLING JUST AHEAD OF THIS FRONT WITH A TONGUE OF DEWPOINTS IN THE THE MID/UPPER 50S. POTENTIAL FOR SEVERE STORMS WILL BE PARTIALLY LIMITED BY STRONG FORCING FROM THIS AREA NORTH AND BEST INSTABILITY FROM THIS AREA SOUTH...WE/LL BE SOMEWHERE IN THE MIDDLE. BEST TIMING APPEARS TO BE FROM MID AFTERNOON INTO EARLY EVENING WITH PEAK HEATING. THE GRADIENT TIGHTENS AHEAD OF THE COLD FRONT ON TUESDAY AND EXPECT SOUTHERLY WINDS IN THE 20 TO 30 MPH RANGE WITH HIGHER GUSTS PERHAPS AS HIGH AS 35 MPH AT TIMES...WHICH WILL BE DEPENDENT ON THE DEPTH OF THE MIXING. WINDS RELAX TUESDAY NIGHT THEN INCREASE AGAIN ON WEDNESDAY FROM THE WEST AS DRIER AIR AND EVENTUALLY COOLER AIR SPREADS ACROSS THE REGION. WITH MOSTLY SUNNY SKIES... TEMPS SHOULD EASILY REBOUND INTO THE 60S WITH 70S POSSIBLE ACROSS THE SOUTHERN CWA BEFORE COLDER AIR ARRIVES. NORTHEAST/EASTERLY FLOW WILL KEEP THE LAKESHORE AREAS COOLER THURSDAY AND FRIDAY WITH ANOTHER STORM SYSTEM TO AFFECT THE AREA FRIDAY INTO SATURDAY. GFS ENDS PRECIP A LITTLE FASTER THAN THE ECMWF SATURDAY BUT OVERALL BOTH ARE IN FAIR AGREEMENT WITH THIS NEXT SYSTEM. CMS && .FIRE WEATHER... 516 AM MONDAY...WINDY CONDITIONS ARE EXPECTED ON TUESDAY AND WEDNESDAY. THE GRADIENT WILL TIGHTEN QUICKLY TUESDAY MORNING WITH SOUTHERLY WINDS INCREASING TO 20 TO 30 MPH BY LATE MORNING WITH HIGHER GUSTS POSSIBLE. DEWPOINTS WILL LIKELY START IN THE 20S TUESDAY MORNING AND THEN QUICKLY INCREASE THROUGH THE 40S AND EVENTUALLY INTO THE 50S LATE TUESDAY AFTERNOON AHEAD OF AN APPROACHING COLD FRONT. BUT BEFORE THE INCREASE IN LOW LEVEL MOISTURE...AS TEMPS RISE...RELATIVE HUMIDITY LEVELS MAY DROP INTO THE 35 TO 40 PERCENT RANGE...ESPECIALLY EAST OF I-55. WINDS THEN SHIFT WESTERLY BEHIND THE COLD FRONT TUESDAY NIGHT. THERE IS STILL SOME UNCERTAINTY REGARDING HOW DEEP THE LOW LEVELS WILL MIX ON WEDNESDAY. THE DEEPER THE MIXING...THE STRONGER THE WINDS/GUSTS AND THE GREATER THE POTENTIAL TO MIX DRIER AIR ALOFT TO THE SURFACE. CURRENTLY HAVE TEMPS RANGING FROM THE MID 60S TO THE LOWER 70S. IF THESE TEMPS MATERIALIZE...COMBINED WITH THE STRONGER WINDS AND DRIER AIR...THEN CONDITIONS MAY APPROACH LOCAL RED FLAG CRITERIA...ESPECIALLY ALONG AND SOUTH OF THE I-80 CORRIDOR. CMS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 10Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING SHEA //DISCUSSION...10Z... THE MAIN LOW END MVFR CLOUDS CONTINUE TO MOVE AWAY FROM ALL OF THE TERMINALS...BUT SOME STRATOCU HAS MOVED IN FROM THE NORTHWEST WHERE SHOWER ACTIVITY IS WORKING SOUTHEAST. GUIDANCE SEEMS TO HAVE A GOOD HANDLE ON THE EXTENT OF THE PRECIP...AND WHILE IT WILL LIKELY BE A NARROW CORRIDOR THAT IS IMPACTED...IT SHOULD REMAIN WEST OF ORD. OBSERVATIONS ARE ALSO SHOWING THAT CIGS WILL REMAIN VFR IF/WHEN PRECIP OCCURS. RADAR/TIME EXTRAPOLATION BRINGS THE SHOWERS INTO RFD BY 10Z AND ACROSS ORD/MDW BY 12-13Z. THE ONE BIG POSITIVE FOR THE EASTERN TERMINALS WILL BE THE AMOUNT OF DRY AIR THAT IS INTRUDING. WHILE RADAR RETURNS WILL LOOK IMPRESSIVE...MUCH WILL FALL AS VIRGA TO START AND EVENTUALLY REACH THE GROUND FROM VFR BASES. DRY AIR WILL CONTINUE TO BLEED IN FROM THE NORTHWEST AND SHOULD SHUT OFF CHANCES FOR ORD/MDW/DPA/GYY EARLY...BUT RFD MAY LINGER A BIT LONGER. SHEA //PREVIOUS 06Z DISCUSSION... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS FALLING WITH RESPECT TO ORD AND MDW...IF THEY WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 10Z... * MODERATE CONFIDENCE ON CIG TRENDS * HIGH CONFIDENCE WITH WIND FORECAST * MODERATE TO LOW WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 255 AM CDT HIGH PRESSURE ACROSS ONTARIO WILL CONTINUE TO SLIDE EAST...ALLOWING COLD AIR TO COME RACING DOWN THE LAKE THIS MORNING. WITH THE STRONG COLD AIR ADVECTION...WINDS HAVE PICKED UP CONSIDERABLY...ALLOWING SOME COASTAL LOCATIONS TO SEE GALE FORCE GUSTS. THOSE HIGHER GUSTS SHOULD BE TEMPORARY...AND WINDS WILL GRADUALLY DIMINISH TO 15 TO 25 KT THROUGHOUT THE DAY. FLOW WILL THEN ORIENT ITSELF TO MORE EASTERLY OVERNIGHT..AND GRADUALLY BECOME SOUTHEAST TOWARDS DAWN. THE GRADIENT WILL TIGHTEN CONSIDERABLY AS LOW PRESSURE LIFTS ACROSS THE PLAINS THIS AFTERNOON...ALLOWING GALE FORCE WINDS ACROSS MUCH OF THE OPEN WATERS...AS WELL AS THE ILLINOIS NEARSHORE WATERS LATE TONIGHT. SURFACE FLOW LOOKS TO BE IN THE LOW 30 KT RANGE FOR MUCH OF THE LAKE...WITH GOOD MIXING OF HIGHER MOMENTUM AIR FROM ALOFT THROUGH AT LEAST THE AFTERNOON ON TUESDAY...WITH GUSTS POTENTIALLY PEAKING BETWEEN 35 AND 40 KT. IT IS INTO THE AFTERNOON AND EVENING HOURS THAT TEMPERATURES ALOFT BEGIN TO WARM...AND WIND GUST POTENTIAL WILL DIMINISH...BUT STILL REMAIN IN THE 25 TO 30 KT RANGE THROUGH DAWN ON WEDNESDAY. ALSO EXTENDED THE SMALL CRAFT ADVISORY FOR THE INDIANA SHORE THROUGH WEDNESDAY. CONFIDENCE IS NOT AS HIGH THAT THEY WILL REACH FULL GALE CRITERIA AS OPPOSED TO THE ILLINOIS SHORES. THE AFOREMENTIONED LOW WILL THEN CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT...BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST AND NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. SHEA && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 4 PM TUESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
458 AM CDT MON MAR 26 2012 .DISCUSSION... 325 AM...WEAK UPPER WAVE SHIFTING SOUTHEAST ACROSS SOUTHERN MN AND SOUTHWEST WI EARLY THIS MORNING WITH AN AREA OF SHOWERS AND A FEW TS. MODELS SEEM CONSISTENT THAT THIS WILL PUSH INTO NORTHWEST IL LATER THIS MORNING. WHILE QPF AMOUNTS WILL BE LIGHT PERHAPS MANY AREAS ONLY SEEING A TRACE...HAVE INCLUDED A CHANCE OF SHOWERS WITH COVERAGE EXPECTED TO DECREASE INTO THE AFTERNOON HRS. DESPITE THE LOW PRECIP CHANCES...APPEARS MOSTLY CLOUDY SKIES WILL PREVAIL THROUGH MUCH OF THE DAY WHICH WILL LIMIT HEATING AS TEMPS ARE NOW FALLING THROUGH THE 40S WITH MANY LOCATIONS ALREADY INTO THE UPPER 30S. STILL EXPECT SOME SUN ACROSS THE SOUTHERN CWA BUT TEMPS ACROSS THE NORTH A BIT TRICKY. OVERALL ONLY TWEAKED THEM LOWER A DEGREE OR TWO BUT THERE IS THE POTENTIAL FOR TEMPS TO BE COOLER THAN CURRENTLY ADVERTISED. FLOW TURNS BACK SOUTHERLY TONIGHT AND COULD BE SOME WARM AIR ADVECTION PRECIP OVERNIGHT INTO EARLY TUESDAY MORNING BUT APPEARS THE BULK OF THIS ACTIVITY WOULD REMAIN NORTH OF THE CWA. BUT SIMILAR TO TODAY/S WAVE...LOOKS LIKE THERE WILL BE PLENTY OF CLOUD COVER AT LEAST ACROSS NORTHERN IL. COULD SEE A QUICK DROP IN TEMPS THIS EVENING AND DEPENDING ON HOW EXTENSIVE CLOUD COVER BECOMES... COULD BE SOME FROST ACROSS THE EASTERN CWA/NORTHWEST INDIANA WHERE LOWS COULD BE IN THE MID 30S. TOO MUCH UNCERTAINTY FOR ANY HEADLINES THIS MORNING AND WILL LET THE DAY SHIFT TAKE A LOOK AT THIS POTENTIAL MORE CLOSELY. LOW PRESSURE WILL LIFT ACROSS THE NORTHERN PLAINS TUESDAY AND ACROSS THE UPPER LAKES TUESDAY NIGHT WITH A TRAILING COLD FRONT SWEEPING ACROSS THE AREA LATE TUESDAY AFTERNOON INTO EARLY WEDNESDAY MORNING. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH MOISTURE POOLING JUST AHEAD OF THIS FRONT WITH A TONGUE OF DEWPOINTS IN THE THE MID/UPPER 50S. POTENTIAL FOR SEVERE STORMS WILL BE PARTIALLY LIMITED BY STRONG FORCING FROM THIS AREA NORTH AND BEST INSTABILITY FROM THIS AREA SOUTH...WE/LL BE SOMEWHERE IN THE MIDDLE. BEST TIMING APPEARS TO BE FROM MID AFTERNOON INTO EARLY EVENING WITH PEAK HEATING. THE GRADIENT TIGHTENS AHEAD OF THE COLD FRONT ON TUESDAY AND EXPECT SOUTHERLY WINDS IN THE 20 TO 30 MPH RANGE WITH HIGHER GUSTS PERHAPS AS HIGH AS 35 MPH AT TIMES...WHICH WILL BE DEPENDENT ON THE DEPTH OF THE MIXING. WINDS RELAX TUESDAY NIGHT THEN INCREASE AGAIN ON WEDNESDAY FROM THE WEST AS DRIER AIR AND EVENTUALLY COOLER AIR SPREADS ACROSS THE REGION. WITH MOSTLY SUNNY SKIES... TEMPS SHOULD EASILY REBOUND INTO THE 60S WITH 70S POSSIBLE ACROSS THE SOUTHERN CWA BEFORE COLDER AIR ARRIVES. NORTHEAST/EASTERLY FLOW WILL KEEP THE LAKESHORE AREAS COOLER THURSDAY AND FRIDAY WITH ANOTHER STORM SYSTEM TO AFFECT THE AREA FRIDAY INTO SATURDAY. GFS ENDS PRECIP A LITTLE FASTER THAN THE ECMWF SATURDAY BUT OVERALL BOTH ARE IN FAIR AGREEMENT WITH THIS NEXT SYSTEM. CMS && .FIRE WEATHER... 255 PM CDT WILL NEED TO MONITOR WEDNESDAY FOR A POTENTIAL HEIGHTENED FIRE DANGER. STRONG WEST WINDS AND DEEP MIXING WILL TAKE PLACE BEHIND A COLD FRONT THAT MOVES THROUGH TUESDAY NIGHT. STILL A LOT OF UNCERTAINTY REGARDING HOW QUICKLY THE COOLER AIR ARRIVES...BUT DOES APPEAR AS THOUGH DEWPOINTS WILL FALL OFF QUICKLY. WILL CONTINUE TO MONITOR TRENDS THE NEXT FEW DAYS. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 10Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING SHEA //DISCUSSION...10Z... THE MAIN LOW END MVFR CLOUDS CONTINUE TO MOVE AWAY FROM ALL OF THE TERMINALS...BUT SOME STRATOCU HAS MOVED IN FROM THE NORTHWEST WHERE SHOWER ACTIVITY IS WORKING SOUTHEAST. GUIDANCE SEEMS TO HAVE A GOOD HANDLE ON THE EXTENT OF THE PRECIP...AND WHILE IT WILL LIKELY BE A NARROW CORRIDOR THAT IS IMPACTED...IT SHOULD REMAIN WEST OF ORD. OBSERVATIONS ARE ALSO SHOWING THAT CIGS WILL REMAIN VFR IF/WHEN PRECIP OCCURS. RADAR/TIME EXTRAPOLATION BRINGS THE SHOWERS INTO RFD BY 10Z AND ACROSS ORD/MDW BY 12-13Z. THE ONE BIG POSITIVE FOR THE EASTERN TERMINALS WILL BE THE AMOUNT OF DRY AIR THAT IS INTRUDING. WHILE RADAR RETURNS WILL LOOK IMPRESSIVE...MUCH WILL FALL AS VIRGA TO START AND EVENTUALLY REACH THE GROUND FROM VFR BASES. DRY AIR WILL CONTINUE TO BLEED IN FROM THE NORTHWEST AND SHOULD SHUT OFF CHANCES FOR ORD/MDW/DPA/GYY EARLY...BUT RFD MAY LINGER A BIT LONGER. SHEA //PREVIOUS 06Z DISCUSSION... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS FALLING WITH RESPECT TO ORD AND MDW...IF THEY WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 10Z... * MODERATE CONFIDENCE ON CIG TRENDS * HIGH CONFIDENCE WITH WIND FORECAST * MODERATE TO LOW WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 255 AM CDT HIGH PRESSURE ACROSS ONTARIO WILL CONTINUE TO SLIDE EAST...ALLOWING COLD AIR TO COME RACING DOWN THE LAKE THIS MORNING. WITH THE STRONG COLD AIR ADVECTION...WINDS HAVE PICKED UP CONSIDERABLY...ALLOWING SOME COASTAL LOCATIONS TO SEE GALE FORCE GUSTS. THOSE HIGHER GUSTS SHOULD BE TEMPORARY...AND WINDS WILL GRADUALLY DIMINISH TO 15 TO 25 KT THROUGHOUT THE DAY. FLOW WILL THEN ORIENT ITSELF TO MORE EASTERLY OVERNIGHT..AND GRADUALLY BECOME SOUTHEAST TOWARDS DAWN. THE GRADIENT WILL TIGHTEN CONSIDERABLY AS LOW PRESSURE LIFTS ACROSS THE PLAINS THIS AFTERNOON...ALLOWING GALE FORCE WINDS ACROSS MUCH OF THE OPEN WATERS...AS WELL AS THE ILLINOIS NEARSHORE WATERS LATE TONIGHT. SURFACE FLOW LOOKS TO BE IN THE LOW 30 KT RANGE FOR MUCH OF THE LAKE...WITH GOOD MIXING OF HIGHER MOMENTUM AIR FROM ALOFT THROUGH AT LEAST THE AFTERNOON ON TUESDAY...WITH GUSTS POTENTIALLY PEAKING BETWEEN 35 AND 40 KT. IT IS INTO THE AFTERNOON AND EVENING HOURS THAT TEMPERATURES ALOFT BEGIN TO WARM...AND WIND GUST POTENTIAL WILL DIMINISH...BUT STILL REMAIN IN THE 25 TO 30 KT RANGE THROUGH DAWN ON WEDNESDAY. ALSO EXTENDED THE SMALL CRAFT ADVISORY FOR THE INDIANA SHORE THROUGH WEDNESDAY. CONFIDENCE IS NOT AS HIGH THAT THEY WILL REACH FULL GALE CRITERIA AS OPPOSED TO THE ILLINOIS SHORES. THE AFOREMENTIONED LOW WILL THEN CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT...BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST AND NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. SHEA && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 4 PM TUESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
410 AM CDT MON MAR 26 2012 .DISCUSSION... 325 AM...WEAK UPPER WAVE SHIFTING SOUTHEAST ACROSS SOUTHERN MN AND SOUTHWEST WI EARLY THIS MORNING WITH AN AREA OF SHOWERS AND A FEW TS. MODELS SEEM CONSISTENT THAT THIS WILL PUSH INTO NORTHWEST IL LATER THIS MORNING. WHILE QPF AMOUNTS WILL BE LIGHT PERHAPS MANY AREAS ONLY SEEING A TRACE...HAVE INCLUDED A CHANCE OF SHOWERS WITH COVERAGE EXPECTED TO DECREASE INTO THE AFTERNOON HRS. DESPITE THE LOW PRECIP CHANCES...APPEARS MOSTLY CLOUDY SKIES WILL PREVAIL THROUGH MUCH OF THE DAY WHICH WILL LIMIT HEATING AS TEMPS ARE NOW FALLING THROUGH THE 40S WITH MANY LOCATIONS ALREADY INTO THE UPPER 30S. STILL EXPECT SOME SUN ACROSS THE SOUTHERN CWA BUT TEMPS ACROSS THE NORTH A BIT TRICKY. OVERALL ONLY TWEAKED THEM LOWER A DEGREE OR TWO BUT THERE IS THE POTENTIAL FOR TEMPS TO BE COOLER THAN CURRENTLY ADVERTISED. FLOW TURNS BACK SOUTHERLY TONIGHT AND COULD BE SOME WARM AIR ADVECTION PRECIP OVERNIGHT INTO EARLY TUESDAY MORNING BUT APPEARS THE BULK OF THIS ACTIVITY WOULD REMAIN NORTH OF THE CWA. BUT SIMILAR TO TODAY/S WAVE...LOOKS LIKE THERE WILL BE PLENTY OF CLOUD COVER AT LEAST ACROSS NORTHERN IL. COULD SEE A QUICK DROP IN TEMPS THIS EVENING AND DEPENDING ON HOW EXTENSIVE CLOUD COVER BECOMES... COULD BE SOME FROST ACROSS THE EASTERN CWA/NORTHWEST INDIANA WHERE LOWS COULD BE IN THE MID 30S. TOO MUCH UNCERTAINTY FOR ANY HEADLINES THIS MORNING AND WILL LET THE DAY SHIFT TAKE A LOOK AT THIS POTENTIAL MORE CLOSELY. LOW PRESSURE WILL LIFT ACROSS THE NORTHERN PLAINS TUESDAY AND ACROSS THE UPPER LAKES TUESDAY NIGHT WITH A TRAILING COLD FRONT SWEEPING ACROSS THE AREA LATE TUESDAY AFTERNOON INTO EARLY WEDNESDAY MORNING. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH MOISTURE POOLING JUST AHEAD OF THIS FRONT WITH A TONGUE OF DEWPOINTS IN THE THE MID/UPPER 50S. POTENTIAL FOR SEVERE STORMS WILL BE PARTIALLY LIMITED BY STRONG FORCING FROM THIS AREA NORTH AND BEST INSTABILITY FROM THIS AREA SOUTH...WE/LL BE SOMEWHERE IN THE MIDDLE. BEST TIMING APPEARS TO BE FROM MID AFTERNOON INTO EARLY EVENING WITH PEAK HEATING. THE GRADIENT TIGHTENS AHEAD OF THE COLD FRONT ON TUESDAY AND EXPECT SOUTHERLY WINDS IN THE 20 TO 30 MPH RANGE WITH HIGHER GUSTS PERHAPS AS HIGH AS 35 MPH AT TIMES...WHICH WILL BE DEPENDENT ON THE DEPTH OF THE MIXING. WINDS RELAX TUESDAY NIGHT THEN INCREASE AGAIN ON WEDNESDAY FROM THE WEST AS DRIER AIR AND EVENTUALLY COOLER AIR SPREADS ACROSS THE REGION. WITH MOSTLY SUNNY SKIES... TEMPS SHOULD EASILY REBOUND INTO THE 60S WITH 70S POSSIBLE ACROSS THE SOUTHERN CWA BEFORE COLDER AIR ARRIVES. NORTHEAST/EASTERLY FLOW WILL KEEP THE LAKESHORE AREAS COOLER THURSDAY AND FRIDAY WITH ANOTHER STORM SYSTEM TO AFFECT THE AREA FRIDAY INTO SATURDAY. GFS ENDS PRECIP A LITTLE FASTER THAN THE ECMWF SATURDAY BUT OVERALL BOTH ARE IN FAIR AGREEMENT WITH THIS NEXT SYSTEM. CMS && .FIRE WEATHER... 255 PM CDT WILL NEED TO MONITOR WEDNESDAY FOR A POTENTIAL HEIGHTENED FIRE DANGER. STRONG WEST WINDS AND DEEP MIXING WILL TAKE PLACE BEHIND A COLD FRONT THAT MOVES THROUGH TUESDAY NIGHT. STILL A LOT OF UNCERTAINTY REGARDING HOW QUICKLY THE COOLER AIR ARRIVES...BUT DOES APPEAR AS THOUGH DEWPOINTS WILL FALL OFF QUICKLY. WILL CONTINUE TO MONITOR TRENDS THE NEXT FEW DAYS. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING OUT WEST SHEA //DISCUSSION...09Z... THE MAIN LOW END MVFR CLOUDS CONTINUE TO MOVE AWAY FROM ALL OF THE TERMINALS...BUT SOME STRATOCU HAS MOVED IN FROM THE NORTHWEST WHERE SHOWER ACTIVITY IS WORKING SOUTHEAST. GUIDANCE SEEMS TO HAVE A GOOD HANDLE ON THE EXTENT OF THE PRECIP...AND WHILE IT WILL LIKELY BE A NARROW CORRIDOR THAT IS IMPACTED...IT SHOULD REMAIN WEST OF ORD. OBSERVATIONS ARE ALSO SHOWING THAT CIGS WILL REMAIN VFR IF/WHEN PRECIP OCCURS. SHEA //PREVIOUS 06Z DISCUSSION... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS MUCH HIGHER THAT ORD/MDW WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 09Z... * MODERATE CONFIDENCE ON CIG TRENDS * LOW CONFIDENCE ON BASES FALLING BELOW 015 OVER THE NEXT FEW HOURS * HIGH CONFIDENCE WITH WIND FORECAST * MODERATE TO HIGH CONFIDENCE WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 255 AM CDT HIGH PRESSURE ACROSS ONTARIO WILL CONTINUE TO SLIDE EAST...ALLOWING COLD AIR TO COME RACING DOWN THE LAKE THIS MORNING. WITH THE STRONG COLD AIR ADVECTION...WINDS HAVE PICKED UP CONSIDERABLY...ALLOWING SOME COASTAL LOCATIONS TO SEE GALE FORCE GUSTS. THOSE HIGHER GUSTS SHOULD BE TEMPORARY...AND WINDS WILL GRADUALLY DIMINISH TO 15 TO 25 KT THROUGHOUT THE DAY. FLOW WILL THEN ORIENT ITSELF TO MORE EASTERLY OVERNIGHT..AND GRADUALLY BECOME SOUTHEAST TOWARDS DAWN. THE GRADIENT WILL TIGHTEN CONSIDERABLY AS LOW PRESSURE LIFTS ACROSS THE PLAINS THIS AFTERNOON...ALLOWING GALE FORCE WINDS ACROSS MUCH OF THE OPEN WATERS...AS WELL AS THE ILLINOIS NEARSHORE WATERS LATE TONIGHT. SURFACE FLOW LOOKS TO BE IN THE LOW 30 KT RANGE FOR MUCH OF THE LAKE...WITH GOOD MIXING OF HIGHER MOMENTUM AIR FROM ALOFT THROUGH AT LEAST THE AFTERNOON ON TUESDAY...WITH GUSTS POTENTIALLY PEAKING BETWEEN 35 AND 40 KT. IT IS INTO THE AFTERNOON AND EVENING HOURS THAT TEMPERATURES ALOFT BEGIN TO WARM...AND WIND GUST POTENTIAL WILL DIMINISH...BUT STILL REMAIN IN THE 25 TO 30 KT RANGE THROUGH DAWN ON WEDNESDAY. ALSO EXTENDED THE SMALL CRAFT ADVISORY FOR THE INDIANA SHORE THROUGH WEDNESDAY. CONFIDENCE IS NOT AS HIGH THAT THEY WILL REACH FULL GALE CRITERIA AS OPPOSED TO THE ILLINOIS SHORES. THE AFOREMENTIONED LOW WILL THEN CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT...BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST AND NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. SHEA && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 4 PM TUESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
325 AM CDT MON MAR 26 2012 .DISCUSSION... 325 AM...WEAK UPPER WAVE SHIFTING SOUTHEAST ACROSS SOUTHERN MN AND SOUTHWEST WI EARLY THIS MORNING WITH AN AREA OF SHOWERS AND A FEW TS. MODELS SEEM CONSISTENT THAT THIS WILL PUSH INTO NORTHWEST IL LATER THIS MORNING. WHILE QPF AMOUNTS WILL BE LIGHT PERHAPS MANY AREAS ONLY SEEING A TRACE...HAVE INCLUDED A CHANCE OF SHOWERS WITH COVERAGE EXPECTED TO DECREASE INTO THE AFTERNOON HRS. DESPITE THE LOW PRECIP CHANCES...APPEARS MOSTLY CLOUDY SKIES WILL PREVAIL THROUGH MUCH OF THE DAY WHICH WILL LIMIT HEATING AS TEMPS ARE NOW FALLING THROUGH THE 40S WITH MANY LOCATIONS ALREADY INTO THE UPPER 30S. STILL EXPECT SOME SUN ACROSS THE SOUTHERN CWA BUT TEMPS ACROSS THE NORTH A BIT TRICKY. OVERALL ONLY TWEAKED THEM LOWER A DEGREE OR TWO BUT THERE IS THE POTENTIAL FOR TEMPS TO BE COOLER THAN CURRENTLY ADVERTISED. FLOW TURNS BACK SOUTHERLY TONIGHT AND COULD BE SOME WARM AIR ADVECTION PRECIP OVERNIGHT INTO EARLY TUESDAY MORNING BUT APPEARS THE BULK OF THIS ACTIVITY WOULD REMAIN NORTH OF THE CWA. BUT SIMILAR TO TODAY/S WAVE...LOOKS LIKE THERE WILL BE PLENTY OF CLOUD COVER AT LEAST ACROSS NORTHERN IL. COULD SEE A QUICK DROP IN TEMPS THIS EVENING AND DEPENDING ON HOW EXTENSIVE CLOUD COVER BECOMES... COULD BE SOME FROST ACROSS THE EASTERN CWA/NORTHWEST INDIANA WHERE LOWS COULD BE IN THE MID 30S. TOO MUCH UNCERTAINTY FOR ANY HEADLINES THIS MORNING AND WILL LET THE DAY SHIFT TAKE A LOOK AT THIS POTENTIAL MORE CLOSELY. LOW PRESSURE WILL LIFT ACROSS THE NORTHERN PLAINS TUESDAY AND ACROSS THE UPPER LAKES TUESDAY NIGHT WITH A TRAILING COLD FRONT SWEEPING ACROSS THE AREA LATE TUESDAY AFTERNOON INTO EARLY WEDNESDAY MORNING. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH MOISTURE POOLING JUST AHEAD OF THIS FRONT WITH A TONGUE OF DEWPOINTS IN THE THE MID/UPPER 50S. POTENTIAL FOR SEVERE STORMS WILL BE PARTIALLY LIMITED BY STRONG FORCING FROM THIS AREA NORTH AND BEST INSTABILITY FROM THIS AREA SOUTH...WE/LL BE SOMEWHERE IN THE MIDDLE. BEST TIMING APPEARS TO BE FROM MID AFTERNOON INTO EARLY EVENING WITH PEAK HEATING. THE GRADIENT TIGHTENS AHEAD OF THE COLD FRONT ON TUESDAY AND EXPECT SOUTHERLY WINDS IN THE 20 TO 30 MPH RANGE WITH HIGHER GUSTS PERHAPS AS HIGH AS 35 MPH AT TIMES...WHICH WILL BE DEPENDENT ON THE DEPTH OF THE MIXING. WINDS RELAX TUESDAY NIGHT THEN INCREASE AGAIN ON WEDNESDAY FROM THE WEST AS DRIER AIR AND EVENTUALLY COOLER AIR SPREADS ACROSS THE REGION. WITH MOSTLY SUNNY SKIES... TEMPS SHOULD EASILY REBOUND INTO THE 60S WITH 70S POSSIBLE ACROSS THE SOUTHERN CWA BEFORE COLDER AIR ARRIVES. NORTHEAST/EASTERLY FLOW WILL KEEP THE LAKESHORE AREAS COOLER THURSDAY AND FRIDAY WITH ANOTHER STORM SYSTEM TO AFFECT THE AREA FRIDAY INTO SATURDAY. GFS ENDS PRECIP A LITTLE FASTER THAN THE ECMWF SATURDAY BUT OVERALL BOTH ARE IN FAIR AGREEMENT WITH THIS NEXT SYSTEM. CMS && .FIRE WEATHER... 255 PM CDT WILL NEED TO MONITOR WEDNESDAY FOR A POTENTIAL HEIGHTENED FIRE DANGER. STRONG WEST WINDS AND DEEP MIXING WILL TAKE PLACE BEHIND A COLD FRONT THAT MOVES THROUGH TUESDAY NIGHT. STILL A LOT OF UNCERTAINTY REGARDING HOW QUICKLY THE COOLER AIR ARRIVES...BUT DOES APPEAR AS THOUGH DEWPOINTS WILL FALL OFF QUICKLY. WILL CONTINUE TO MONITOR TRENDS THE NEXT FEW DAYS. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING SHEA //DISCUSSION...UPDATED 06Z... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS MUCH HIGHER THAT ORD/MDW WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MODERATE TO HIGH CONFIDENCE ON CIG TRENDS * LOW CONFIDENCE ON BASES FALLING BELOW 015 OVER THE NEXT FEW HOURS * HIGH CONFIDENCE WITH WIND FORECAST * HIGH CONFIDENCE WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 255 AM CDT HIGH PRESSURE ACROSS ONTARIO WILL CONTINUE TO SLIDE EAST...ALLOWING COLD AIR TO COME RACING DOWN THE LAKE THIS MORNING. WITH THE STRONG COLD AIR ADVECTION...WINDS HAVE PICKED UP CONSIDERABLY...ALLOWING SOME COASTAL LOCATIONS TO SEE GALE FORCE GUSTS. THOSE HIGHER GUSTS SHOULD BE TEMPORARY...AND WINDS WILL GRADUALLY DIMINISH TO 15 TO 25 KT THROUGHOUT THE DAY. FLOW WILL THEN ORIENT ITSELF TO MORE EASTERLY OVERNIGHT..AND GRADUALLY BECOME SOUTHEAST TOWARDS DAWN. THE GRADIENT WILL TIGHTEN CONSIDERABLY AS LOW PRESSURE LIFTS ACROSS THE PLAINS THIS AFTERNOON...ALLOWING GALE FORCE WINDS ACROSS MUCH OF THE OPEN WATERS...AS WELL AS THE ILLINOIS NEARSHORE WATERS LATE TONIGHT. SURFACE FLOW LOOKS TO BE IN THE LOW 30 KT RANGE FOR MUCH OF THE LAKE...WITH GOOD MIXING OF HIGHER MOMENTUM AIR FROM ALOFT THROUGH AT LEAST THE AFTERNOON ON TUESDAY...WITH GUSTS POTENTIALLY PEAKING BETWEEN 35 AND 40 KT. IT IS INTO THE AFTERNOON AND EVENING HOURS THAT TEMPERATURES ALOFT BEGIN TO WARM...AND WIND GUST POTENTIAL WILL DIMINISH...BUT STILL REMAIN IN THE 25 TO 30 KT RANGE THROUGH DAWN ON WEDNESDAY. ALSO EXTENDED THE SMALL CRAFT ADVISORY FOR THE INDIANA SHORE THROUGH WEDNESDAY. CONFIDENCE IS NOT AS HIGH THAT THEY WILL REACH FULL GALE CRITERIA AS OPPOSED TO THE ILLINOIS SHORES. THE AFOREMENTIONED LOW WILL THEN CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT...BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST AND NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. SHEA && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 4 PM TUESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
300 AM CDT MON MAR 26 2012 .DISCUSSION... 255 PM CDT PRIMARY FORECAST CHALLENGES TODAY INCLUDE TEMPS THE NEXT COUPLE DAYS FOLLOWED BY PRECIP CHANCES WITH COLD FRONT APPROACHING TUESDAY NIGHT. ANOTHER REMARKABLY MILD DAY ON TAP ACROSS THE REGION WITH THE ONLY EXCEPTION BEING NEAR THE LAKE WHERE MORE ESTABLISHED LAKE BREEZE HAS KNOCKED TEMPS BACK DOWN INTO THE 50S...WITH EVEN SOME VERY LOW STRATUS/DENSE FOG RIGHT ALONG THE IMMEDIATE SHORE. FAIRLY STRONG HIGH PRESSURE OVER MANITOBA WILL MOVE SOUTHEAST TOWARD QUEBEC TONIGHT WITH STRENGTHENING NORTHERLY FLOW USHERING IN A COLDER AND DRIER AIR MASS INTO THE AREA TONIGHT. SKY COVER WILL BE TRICKY THE NEXT 24-48 HOURS...PARTICULARLY NEAR THE LAKE. SHORTWAVE IS PROGGED TO CREST THE RIDGE AND APPROACH FROM THE NORTHWEST TONIGHT AND RESULT IN INCREASING CLOUDINESS ON THE SYNOPTIC SCALE. IN FACT...NOT OUT OF THE QUESTION THAT THERE COULD EVEN BE A FEW SPRINKLES OR LIGHT SHOWERS OVER WESTERN PORTIONS OF THE CWA LATE TONIGHT/EARLY MONDAY. LAKE EFFECT STRATUS SHOULD GENERALLY BE ON THE DECREASE THIS EVENING WITH COLDER AIR FILTERING IN ALOFT WILL LIKELY SEE AN EVENTUAL TRANSITION TO LAKE EFFECT INSTABILITY STRATOCUMULUS LATE TONIGHT AND ESPECIALLY INTO MONDAY. HEIGHTS ALOFT BEGIN TO RISE MONDAY BUT SURFACE HIGH ISN`T QUITE AS PROGRESSIVE RESULTING IN A CHILLY NORTHEAST WIND OFF THE LAKE. IN FACT...WITH THE WINDS OFF THE LAKE AND THE CLOUD COVER TEMPS MAY BE HARD PRESSED TO CLIMB ABOVE AVERAGE FOR THE FIRST TIME IN WEEKS. ONE POSSIBLE SAVING GRACE KEEPING IT FROM BEING EVEN COLDER TOMORROW IS THE FACT LAKE TEMPS ARE APPROACHING 50F NOW...SO EVEN WITH A LONG FETCH NORTHEAST WIND TEMPS WILL PROBABLY ONLY BE HELD IN THE 40S. WINDS SHOULD VEER TO SOUTHEASTERLY MONDAY NIGHT AND EVENTUALLY SOUTH BY TUESDAY WITH WARMER AIR EVENTUALLY SPREADING NORTH INTO THE AREA. DOES APPEAR AS THOUGH THERE COULD BE A FAIR AMOUNT OF CLOUD COVER PLUS THE COOL START TO THE DAY SHOULD RESULT IN HIGHS PROBABLY HOLDING IN THE 60S...WHICH IS STILL WELL ABOVE AVERAGE. STRONG UPPER LOW AND ASSOCIATED SURFACE LOWS TRACK EAST ALONG THE CANADIAN BORDER TO OUR NORTH TUESDAY NIGHT WITH TRAILING COLD FRONT LIKELY TO MOVE ACROSS THE REGION TUESDAY NIGHT. MOISTURE RETURN DOES NT LOOK ALL THAT IMPRESSIVE AND SOMEWHAT DISJOINTED FROM THE STRONGER/DEEPER ASCENT THAT OCCURS FARTHER NORTH CLOSER TO THE UPPER LOW TRACK. BASED ON THE 12Z MODEL RUNS...NOT OVERLY IMPRESSED WITH OUR CONVECTIVE CHANCES AS FRONTAL TIMING IS LESS THAN IDEAL AND MOISTURE AND FORCING ARE BOTH MARGINAL TO DECENT AT BEST. HAVE MAINTAINED JUST CHANCE POPS FOR NOW WHICH ARE IN LINE WITH THE OBJECTIVE GUIDANCE NUMBERS. WINDS SHIFT TO THE WEST BEHIND THE COLD FRONT...BUT WITH STRONG MIXING AND OFFSHORE FLOW PLUS COLDER AIR LAGGING WELL BEHIND THE FRONT...WEDNESDAY LOOKS TO BE AS WARM IF NOT A BIT A WARMER OF A DAY THAN TUESDAY OUT AHEAD OF THE COLD FRONT. HAVE BUMPED TEMPS UP CLOSER TO IN LINE WITH WRF-NAM 2M TEMPS...BUT EVEN GOING FORECAST COULD BE A BIT CONSERVATIVE STILL GIVEN DEEP MIXING AND FULL SUNSHINE. ANOTHER SHOT OF COOLER MORE SEASONABLE TEMPS ARRIVE LATE IN THE WEEK WITH ANOTHER PERIOD OF NORTHEAST TO EAST WINDS OFF THE LAKE. DIFFERENCES APPEAR IN THE MEDIUM RANGE MODELS HEADING INTO NEXT WEEKEND WITH VARYING IDEAS ON THE PLACEMENT OF THE UPPER RIDGE AS WELL AS TIMING/INTENSITY OF VARIOUS WAVES RIPPLING THROUGH THE FLOW. GENERALLY DOES APPEAR THERE COULD BE ONE OR TWO BOUTS OF PRECIPITATION BUT WITH TIMING NEXT TO IMPOSSIBLE AT THIS POINT HAVE JUST BLANKETED SEVERAL PERIODS WITH SOME LOW ENDS POPS HEADING INTO NEXT WEEKEND...THOUGH AT THIS DISTANCE IT CERTAINLY IS NOT LOOKING LIKE A WASH OUT. IZZI && .FIRE WEATHER... 255 PM CDT WILL NEED TO MONITOR WEDNESDAY FOR A POTENTIAL HEIGHTENED FIRE DANGER. STRONG WEST WINDS AND DEEP MIXING WILL TAKE PLACE BEHIND A COLD FRONT THAT MOVES THROUGH TUESDAY NIGHT. STILL A LOT OF UNCERTAINTY REGARDING HOW QUICKLY THE COOLER AIR ARRIVES...BUT DOES APPEAR AS THOUGH DEWPOINTS WILL FALL OFF QUICKLY. WILL CONTINUE TO MONITOR TRENDS THE NEXT FEW DAYS. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING SHEA //DISCUSSION...UPDATED 06Z... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS MUCH HIGHER THAT ORD/MDW WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MODERATE TO HIGH CONFIDENCE ON CIG TRENDS * LOW CONFIDENCE ON BASES FALLING BELOW 015 OVER THE NEXT FEW HOURS * HIGH CONFIDENCE WITH WIND FORECAST * HIGH CONFIDENCE WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 255 AM CDT HIGH PRESSURE ACROSS ONTARIO WILL CONTINUE TO SLIDE EAST...ALLOWING COLD AIR TO COME RACING DOWN THE LAKE THIS MORNING. WITH THE STRONG COLD AIR ADVECTION...WINDS HAVE PICKED UP CONSIDERABLY...ALLOWING SOME COASTAL LOCATIONS TO SEE GALE FORCE GUSTS. THOSE HIGHER GUSTS SHOULD BE TEMPORARY...AND WINDS WILL GRADUALLY DIMINISH TO 15 TO 25 KT THROUGHOUT THE DAY. FLOW WILL THEN ORIENT ITSELF TO MORE EASTERLY OVERNIGHT..AND GRADUALLY BECOME SOUTHEAST TOWARDS DAWN. THE GRADIENT WILL TIGHTEN CONSIDERABLY AS LOW PRESSURE LIFTS ACROSS THE PLAINS THIS AFTERNOON...ALLOWING GALE FORCE WINDS ACROSS MUCH OF THE OPEN WATERS...AS WELL AS THE ILLINOIS NEARSHORE WATERS LATE TONIGHT. SURFACE FLOW LOOKS TO BE IN THE LOW 30 KT RANGE FOR MUCH OF THE LAKE...WITH GOOD MIXING OF HIGHER MOMENTUM AIR FROM ALOFT THROUGH AT LEAST THE AFTERNOON ON TUESDAY...WITH GUSTS POTENTIALLY PEAKING BETWEEN 35 AND 40 KT. IT IS INTO THE AFTERNOON AND EVENING HOURS THAT TEMPERATURES ALOFT BEGIN TO WARM...AND WIND GUST POTENTIAL WILL DIMINISH...BUT STILL REMAIN IN THE 25 TO 30 KT RANGE THROUGH DAWN ON WEDNESDAY. ALSO EXTENDED THE SMALL CRAFT ADVISORY FOR THE INDIANA SHORE THROUGH WEDNESDAY. CONFIDENCE IS NOT AS HIGH THAT THEY WILL REACH FULL GALE CRITERIA AS OPPOSED TO THE ILLINOIS SHORES. THE AFOREMENTIONED LOW WILL THEN CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT...BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST AND NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. SHEA && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 4 PM TUESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
254 AM CDT MON MAR 26 2012 .DISCUSSION... ISSUED 254 AM CDT MON MAR 26 2012 SHORT TERM...TODAY THROUGH WEDNESDAY BACKDOOR COLD FRONT WILL SINK THROUGH CENTRAL ILLINOIS THIS MORNING...ALLOWING A MUCH COOLER AIRMASS TO FILTER IN FROM THE NORTHEAST. THANKS TO CLOUD COVER AND AN E/NE FETCH OVER THE COLD WATERS OF LAKE MICHIGAN...AREAS ALONG AND NORTH OF I-74 WILL REMAIN IN THE 50S. FURTHER SOUTH...HIGH TEMPS WILL REACH THE LOWER TO MIDDLE 60S. AN AREA OF LIGHT SHOWERS ASSOCIATED WITH ISENTROPIC LIFT BEHIND THE BOUNDARY WILL TRACK SOUTHEASTWARD OUT OF MINNESOTA...BUT SHOULD STAY NORTH OF THE I-80 CORRIDOR THIS MORNING. AS UPPER RIDGE OVER THE PLAINS BUILDS EASTWARD...FRONT WILL GET PUSHED BACK NORTHWARD TONIGHT. THIS WILL RESULT IN A RETURN TO MUCH WARMER CONDITIONS FOR TUESDAY...WITH HIGH TEMPS ONCE AGAIN SOARING WELL INTO THE 70S. MEANWHILE...REMNANTS OF UPPER LOW CURRENTLY OVER SOUTHERN CALIFORNIA WILL LIFT NORTHEASTWARD INTO THE UPPER MIDWEST...FLATTENING THE PREVAILING RIDGE AND PUSHING A COLD FRONT TOWARD CENTRAL ILLINOIS. MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT REGARDING TIMING OF FROPA TUESDAY NIGHT. AIRMASS AHEAD OF THE APPROACHING BOUNDARY WILL BECOME MODERATELY UNSTABLE TUESDAY AFTERNOON...WITH LIFTED INDEX VALUES REACHING THE -4 TO -6C RANGE. DESPITE GOOD INSTABILITY...CONVERGENCE ALONG FRONT WILL BE MINIMAL AND BEST UPPER DYNAMICS WILL REMAIN WELL TO THE N/NW. AS A RESULT...AM ONLY EXPECTING SCATTERED CONVECTION WITH THE FRONT. WILL MAINTAIN CHANCE POPS WEST OF I-55 TUESDAY AFTERNOON...THEN ACROSS THE BOARD TUESDAY NIGHT. FRONT WILL SETTLE SOUTHWARD INTO THE OHIO RIVER VALLEY ON WEDNESDAY...WITH PERHAPS A FEW LINGERING SHOWERS ACROSS THE FAR SE KILX CWA DURING THE MORNING. DESPITE FRONTAL PASSAGE...PACIFIC ORIGIN AIRMASS AND AMPLE SUNSHINE WILL ALLOW HIGH TEMPS TO ONCE AGAIN CLIMB INTO THE 70S. LONG TERM...THURSDAY THROUGH SUNDAY AFTER A WARM/DRY DAY ON THURSDAY...A PERIOD OF UNSETTLED WEATHER IS SETTING UP FOR THE END OF THE WEEK. BOTH THE GFS AND ECMWF CONTINUE TO ADVERTISE A ZONAL UPPER FLOW PATTERN DEVELOPING ACROSS THE CONUS BY THE WEEKEND INTO NEXT WEEK...WITH A SERIES OF DISTURBANCES EXPECTED TO TRACK FROM WEST TO EAST ACROSS THE COUNTRY. THE FIRST WAVE WILL APPROACH LATE THURSDAY NIGHT INTO FRIDAY...CAUSING THE OHIO RIVER VALLEY FRONT TO LIFT BACK NORTHWARD INTO THE AREA. WITH A BOUNDARY IN PLACE...PLENTY OF MOISTURE FLOWING NORTHWARD FROM THE GULF...AND A SHORT-WAVE TO PROVIDE LIFT...SHOWERS AND THUNDERSTORMS WILL BE A GOOD BET FOR BOTH FRIDAY AND SATURDAY. AFTER THAT...WAVE WILL PASS TO THE EAST AND DRY WEATHER WILL RETURN BY SUNDAY. BARNES && .AVIATION... ISSUED 1145 PM CDT SUN MAR 25 2012 COLD FRONT/LAKE BREEZE COMPOSITE BOUNDARY MAKING ITS WAY SOUTHWESTWARD THROUGH NORTHERN IL AND IS NEARING PIA/BMI. MAIN FORECAST CHALLENGE WILL BE IF ANY MVFR CLOUDS DEVELOP AFTER FRONTAL PASSAGE THROUGH SUNRISE. FORECAST SOUNDINGS FROM THE LATEST RUC DO SUPPORT CLOUD STRATOCU DEVELOPMENT AT ABOUT 5K FT FOR ALL TAF SITES...WITH A PERIOD OF 1K-2K FT CLOUDS IN THE 08Z-12Z TIME FRAME FOR ONLY PIA/BMI. ALTHOUGH THE SOUNDINGS DO NOT SHOW MVFR CLOUDS IN THE SPI-DEC-CMI CORRIDOR... WILL GIVE THEM A SCT LAYER AT 2K FT. BROKEN VFR STRATOCU WILL THEN DOMINATE ALL SITES THROUGH AT LEAST 00Z...THEN SOME BREAKUP MAY OCCUR SPI-DEC-CMI. WINDS BEHIND THE FRONT WILL INCREASE FROM THE EAST 14-18 KT AND HOLD UP THROUGH THE PERIOD...WITH GUSTS 25-30 KT DURING THE DAY MONDAY. 04 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
108 AM CDT MON MAR 26 2012 .DISCUSSION... 255 PM CDT PRIMARY FORECAST CHALLENGES TODAY INCLUDE TEMPS THE NEXT COUPLE DAYS FOLLOWED BY PRECIP CHANCES WITH COLD FRONT APPROACHING TUESDAY NIGHT. ANOTHER REMARKABLY MILD DAY ON TAP ACROSS THE REGION WITH THE ONLY EXCEPTION BEING NEAR THE LAKE WHERE MORE ESTABLISHED LAKE BREEZE HAS KNOCKED TEMPS BACK DOWN INTO THE 50S...WITH EVEN SOME VERY LOW STRATUS/DENSE FOG RIGHT ALONG THE IMMEDIATE SHORE. FAIRLY STRONG HIGH PRESSURE OVER MANITOBA WILL MOVE SOUTHEAST TOWARD QUEBEC TONIGHT WITH STRENGTHENING NORTHERLY FLOW USHERING IN A COLDER AND DRIER AIR MASS INTO THE AREA TONIGHT. SKY COVER WILL BE TRICKY THE NEXT 24-48 HOURS...PARTICULARLY NEAR THE LAKE. SHORTWAVE IS PROGGED TO CREST THE RIDGE AND APPROACH FROM THE NORTHWEST TONIGHT AND RESULT IN INCREASING CLOUDINESS ON THE SYNOPTIC SCALE. IN FACT...NOT OUT OF THE QUESTION THAT THERE COULD EVEN BE A FEW SPRINKLES OR LIGHT SHOWERS OVER WESTERN PORTIONS OF THE CWA LATE TONIGHT/EARLY MONDAY. LAKE EFFECT STRATUS SHOULD GENERALLY BE ON THE DECREASE THIS EVENING WITH COLDER AIR FILTERING IN ALOFT WILL LIKELY SEE AN EVENTUAL TRANSITION TO LAKE EFFECT INSTABILITY STRATOCUMULUS LATE TONIGHT AND ESPECIALLY INTO MONDAY. HEIGHTS ALOFT BEGIN TO RISE MONDAY BUT SURFACE HIGH ISN`T QUITE AS PROGRESSIVE RESULTING IN A CHILLY NORTHEAST WIND OFF THE LAKE. IN FACT...WITH THE WINDS OFF THE LAKE AND THE CLOUD COVER TEMPS MAY BE HARD PRESSED TO CLIMB ABOVE AVERAGE FOR THE FIRST TIME IN WEEKS. ONE POSSIBLE SAVING GRACE KEEPING IT FROM BEING EVEN COLDER TOMORROW IS THE FACT LAKE TEMPS ARE APPROACHING 50F NOW...SO EVEN WITH A LONG FETCH NORTHEAST WIND TEMPS WILL PROBABLY ONLY BE HELD IN THE 40S. WINDS SHOULD VEER TO SOUTHEASTERLY MONDAY NIGHT AND EVENTUALLY SOUTH BY TUESDAY WITH WARMER AIR EVENTUALLY SPREADING NORTH INTO THE AREA. DOES APPEAR AS THOUGH THERE COULD BE A FAIR AMOUNT OF CLOUD COVER PLUS THE COOL START TO THE DAY SHOULD RESULT IN HIGHS PROBABLY HOLDING IN THE 60S...WHICH IS STILL WELL ABOVE AVERAGE. STRONG UPPER LOW AND ASSOCIATED SURFACE LOWS TRACK EAST ALONG THE CANADIAN BORDER TO OUR NORTH TUESDAY NIGHT WITH TRAILING COLD FRONT LIKELY TO MOVE ACROSS THE REGION TUESDAY NIGHT. MOISTURE RETURN DOESNT LOOK ALL THAT IMPRESSIVE AND SOMEWHAT DISJOINTED FROM THE STRONGER/DEEPER ASCENT THAT OCCURS FARTHER NORTH CLOSER TO THE UPPER LOW TRACK. BASED ON THE 12Z MODEL RUNS...NOT OVERLY IMPRESSED WITH OUR CONVECTIVE CHANCES AS FRONTAL TIMING IS LESS THAN IDEAL AND MOISTURE AND FORCING ARE BOTH MARGINAL TO DECENT AT BEST. HAVE MAINTAINED JUST CHANCE POPS FOR NOW WHICH ARE IN LINE WITH THE OBJECTIVE GUIDANCE NUMBERS. WINDS SHIFT TO THE WEST BEHIND THE COLD FRONT...BUT WITH STRONG MIXING AND OFFSHORE FLOW PLUS COLDER AIR LAGGING WELL BEHIND THE FRONT...WEDNESDAY LOOKS TO BE AS WARM IF NOT A BIT A WARMER OF A DAY THAN TUESDAY OUT AHEAD OF THE COLD FRONT. HAVE BUMPED TEMPS UP CLOSER TO IN LINE WITH WRF-NAM 2M TEMPS...BUT EVEN GOING FORECAST COULD BE A BIT CONSERVATIVE STILL GIVEN DEEP MIXING AND FULL SUNSHINE. ANOTHER SHOT OF COOLER MORE SEASONABLE TEMPS ARRIVE LATE IN THE WEEK WITH ANOTHER PERIOD OF NORTHEAST TO EAST WINDS OFF THE LAKE. DIFFERENCES APPEAR IN THE MEDIUM RANGE MODELS HEADING INTO NEXT WEEKEND WITH VARYING IDEAS ON THE PLACEMENT OF THE UPPER RIDGE AS WELL AS TIMING/INTENSITY OF VARIOUS WAVES RIPPLING THROUGH THE FLOW. GENERALLY DOES APPEAR THERE COULD BE ONE OR TWO BOUTS OF PRECIPITATION BUT WITH TIMING NEXT TO IMPOSSIBLE AT THIS POINT HAVE JUST BLANKETED SEVERAL PERIODS WITH SOME LOW ENDS POPS HEADING INTO NEXT WEEKEND...THOUGH AT THIS DISTANCE IT CERTAINLY IS NOT LOOKING LIKE A WASH OUT. IZZI && .FIRE WEATHER... 255 PM CDT WILL NEED TO MONITOR WEDNESDAY FOR A POTENTIAL HEIGHTENED FIRE DANGER. STRONG WEST WINDS AND DEEP MIXING WILL TAKE PLACE BEHIND A COLD FRONT THAT MOVES THROUGH TUESDAY NIGHT. STILL A LOT OF UNCERTAINTY REGARDING HOW QUICKLY THE COOLER AIR ARRIVES...BUT DOES APPEAR AS THOUGH DEWPOINTS WILL FALL OFF QUICKLY. WILL CONTINUE TO MONITOR TRENDS THE NEXT FEW DAYS. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CIG TRENDS OVERNIGHT * NE WINDS AND GUSTS THROUGH THE MORNING * PRECIP POTENTIAL IN THE MORNING SHEA //DISCUSSION...UPDATED 06Z... EARLY EVENING STRATUS HAS SHIFTED TO THE SOUTH AND AND WEST OF THE EASTERN TERMINALS AS OF 06Z...AND THE TREND OF CIGS RAISING AND OVERALL COVERAGE DECREASING...WILL CONTINUE. 11-3.9UM SATELLITE IMAGERY NOT SHOWING MUCH WITH REGARDS TO LOW CLOUDS ACROSS THE LAKE...WITH THE BULK OF THE LAKE STRATUS STAYING GENERALLY IN THE MKE TO RAC CORRIDOR. THERE ARE SOME HINTS THAT SOME OF THE LOWER CLOUDS MAY LINGER AROUND THE UGN/PWK AND MAYBE ORD TERMINALS THROUGH ABOUT 10Z...AND WITH THE UNCERTAINTY...WILL MAINTAIN THE TEMPO...BUT RAISE HEIGHTS. THROUGH THE REST OF THE NIGHT AND INTO THE DAY TOMORROW...WINDS WILL GRADUALLY WORK THEIR WAY AROUND THE COMPASS...GOING FROM NE TO E AND EVENTUALLY SE-SSE LATE TOMORROW NIGHT. GUSTS WILL ALSO BE ON THE DOWN TREND INTO THE MORNING HOURS...AND WILL HOLD OUT ON THE LOW 20S TO UPPER TEENS GUSTS THROUGH THE 18Z HOUR. PRECIP CHANCES WILL BE TRICKIEST FOR RFD THIS MORNING. GUIDANCE IS BRINGING SHOWERS THAT ARE CURRENTLY WEST OF LSE...SOUTHEAST AND ACROSS RFD INTO THE 12Z HOUR. RAW EXTRAPOLATION FROM RADAR IS A LITTLE CLOSER TO 11Z...BUT ONE THING THE MODELS MAY BE STRUGGLING WITH IS HOW DRY THE AIRMASS MOVING IN FROM THE NORTH ACTUALLY IS. NOT FULLY CONFIDENT THAT THE SHOWERS WILL LAST BEFORE FALLING APART...AND WILL ADD A PERIOD OF VCSH FROM 11 TO 15Z DUE TO THE UNCERTAINTY AT THIS POINT. CONFIDENCE IS MUCH HIGHER THAT ORD/MDW WILL REMAIN DRY...THOUGH THE 03Z HRRR IS REALLY INCREASING THE SHOWERS. WILL NEED TO MONITOR AND ADJUST AS NECESSARY. SHEA //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MODERATE TO HIGH CONFIDENCE ON CIG TRENDS * LOW CONFIDENCE ON BASES FALLING BELOW 015 OVER THE NEXT FEW HOURS * HIGH CONFIDENCE WITH WIND FORECAST * HIGH CONFIDENCE WITH ORD/MDW STAYING DRY THIS MORNING SHEA //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 06Z... * TUESDAY...GUSTY SOUTHERLY WINDS. A SLIGHT CHC OF TSRA FROM MID AFTN INTO THE EVE. LLWS POTENTIAL IN THE EVENING AND EARLY OVERNIGHT. * WEDNESDAY...MVFR POSSIBLE DURING THE NIGHT. * THURSDAY...VFR. * FRIDAY...CHC OF TSRA. * SATURDAY...CHC OF TSRA. SHEA && .MARINE... 247 PM CDT DENSE FOG AND GALE POTENTIAL TUESDAY ARE THE MAIN FORECAST CONCERNS THIS AFTERNOON. AREAS OF DENSE FOG CONTINUE ACROSS SOUTHERN LAKE MICHIGAN THIS AFTERNOON BUT ARE EXPECTED TO DISSIPATE INTO EARLY EVENING. OTHERWISE...TWO AREAS OF LOW PRESSURE...ONE ACROSS EASTER QUEBEC...AND ANOTHER OFF THE EASTERN SEABOARD...WILL MERGE TO THE EAST OF NOVA SCOTIA MONDAY THEN DEEPEN. MEANWHILE...HIGH PRESSURE IS MOVING INTO WESTERN ONTARIO. THE GRADIENT BETWEEN THE MERGING LOWS AND THE HIGH WILL TIGHTEN ACROSS LAKE MICHIGAN THIS EVENING LEADING TO INCREASING NORTHEASTERLY WINDS ACROSS THE LAKE TONIGHT. EXPECT SPEEDS IN THE 25-30 KT RANGE BY MID/LATE EVENING ACROSS MUCH OF THE LAKE. SPEEDS WILL EASE OFF MONDAY AS THE GRADIENT WEAKENS WITH THE RIDGE AXIS ASSOCIATED WITH THE HIGH CROSSING THE LAKE. WILL CONTINUE WITH THE SMALL CRAFT ADVISORY FROM THIS EVENING INTO MONDAY NIGHT FOR WINDS AND WAVES...THOUGH WINDS SHOULD EASE MONDAY...WAVES WILL CONTINUE TO BE HIGH INTO MONDAY NIGHT. STRONG LOW PRESSURE WILL DEVELOP ACROSS THE NORTHERN HIGH PLAINS MONDAY NIGHT AND MOVE EAST-NORTHEASTWARD TO NORTHERN LAKE SUPERIOR WHILE WEAKENING SLIGHTLY TUESDAY NIGHT. AS A RESULT...WINDS WILL TURN SOUTHEASTERLY MONDAY EVENING AS THE RIDGE MOVES EAST AND THE GRADIENT TIGHTENS AHEAD OF THE APPROACHING LOW. COOLER AIR WILL BE IN PLACE ALOFT WHICH WILL SUPPORT UNSTABLE CONDITIONS ACROSS THE LAKE. AS LOW LEVEL WINDS RAMP UP MIXING WILL BRING HIGHER SPEEDS TO THE LAKE SURFACE AND AM CONTINUING TO SEE GOOD POTENTIAL FOR 35-40 KT GALES FROM EARLY TUESDAY THROUGH MUCH OF THE AFTERNOON. THE TRICKY PART WILL BE ACCOUNTING FOR INCREASING WARM AIR ALOFT DEVELOPING AN INVERSION WHICH WILL LIMIT MIXING. THIS WILL LIKELY RESULT IN DECREASING GUSTS FROM SOUTH TO NORTH FROM TUESDAY AFTERNOON INTO THE EVENING. THE GRADIENT WILL REMAIN TIGHT SO SPEEDS WILL BE ELEVATED BUT PROBABLY BELOW GALE AS THIS OCCURS. THE DIRECTIONS WILL TURN MORE SOUTHERLY THROUGH THE DAY AS WELL. WILL HOIST A GALE WATCH FOR THE OPEN WATERS FROM LATE MONDAY NIGHT THROUGH TUESDAY. WITH THE CURRENT SMALL CRAFT IN EFFECT AND LESSER CONFIDENCE IN GALE CONDITIONS ACROSS THE IL/IN NEARSHORE WATERS WILL KEEP THOSE AREAS FREE OF HEADLINES FOR NOW BUT WILL LIKELY NEED TO AT LEAST EXTEND THE SMALL CRAFT THROUGH MUCH OF TUESDAY. THE LOW WILL CROSS NORTHERN LAKE SUPERIOR TUESDAY NIGHT BRINGING WINDS AROUND TO THE WEST...THEN NORTHWEST THEN NORTH AS ANOTHER AREA OF HIGH PRESSURE APPROACHES FROM THE WEST. WINDS WILL THEN TURN SOUTHEASTERLY INTO FRIDAY AS THE HIGH SHIFTS TO THE EAST. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM TUESDAY. GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...4 AM TUESDAY TO 7 PM TUESDAY. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1145 PM CDT SUN MAR 25 2012 .DISCUSSION... ISSUED 830 PM CDT SUN MAR 25 2012 QUIET WEATHER ON TAP FOR CENTRAL IL TONIGHT. A COLD FRONT ENTERING NORTHERN IL WILL CONTINUE SOUTHWARD OVERNIGHT AND PASS THROUGH THE AREA BY SUNRISE. ONLY SENSIBLE WEATHER WILL BE AN INCREASE IN CLOUDS AND A WIND SHIFT TO THE EAST. THUNDERSTORMS ARE INCREASING TO THE NORTH OF THE WESTERN EXTENSION OF THE COLD FRONT...WHICH LIES STATIONARY ACROSS NEB. THIS ACTIVITY WILL REMAIN WELL NORTH OF THE AREA OVERNIGHT AND MONDAY. AFTERNOON FORECAST PACKAGE LOOKS GOOD AND DO NOT EXPECT THE NEED FOR CHANGES THEREIN. 04 && .AVIATION... ISSUED 1145 PM CDT SUN MAR 25 2012 COLD FRONT/LAKE BREEZE COMPOSITE BOUNDARY MAKING ITS WAY SOUTHWESTWARD THROUGH NORTHERN IL AND IS NEARING PIA/BMI. MAIN FORECAST CHALLENGE WILL BE IF ANY MVFR CLOUDS DEVELOP AFTER FRONTAL PASSAGE THROUGH SUNRISE. FORECAST SOUNDINGS FROM THE LATEST RUC DO SUPPORT CLOUD STRATOCU DEVELOPMENT AT ABOUT 5K FT FOR ALL TAF SITES...WITH A PERIOD OF 1K-2K FT CLOUDS IN THE 08Z-12Z TIME FRAME FOR ONLY PIA/BMI. ALTHOUGH THE SOUNDINGS DO NOT SHOW MVFR CLOUDS IN THE SPI-DEC-CMI CORRIDOR... WILL GIVE THEM A SCT LAYER AT 2K FT. BROKEN VFR STRATOCU WILL THEN DOMINATE ALL SITES THROUGH AT LEAST 00Z...THEN SOME BREAKUP MAY OCCUR SPI-DEC-CMI. WINDS BEHIND THE FRONT WILL INCREASE FROM THE EAST 14-18 KT AND HOLD UP THROUGH THE PERIOD...WITH GUSTS 25-30 KT DURING THE DAY MONDAY. 04 && .PREV DISCUSSION... ISSUED 300 PM CDT SUN MAR 25 2012 SEVERAL COLD FRONTAL PASSAGES WILL HIGHLIGHT THE FORECAST OVER THE NEXT WEEK. THE FIRST COLD FRONT WILL DROP SOUTH ACROSS CENTRAL IL TONIGHT. THAT WILL SHIFT THE WINDS AROUND TO THE NORTH AND BRING COLDER TEMPS FOR MONDAY. HOWEVER...HIGHS ON TUES WILL JUMP 10-12 DEG AS THE FRONT RETURNS NORTH AS A WARM FRONT. THE SECOND COLD FRONT WILL ARRIVE ON WED WITH A COOLER DAY ON THURSDAY. THE TIMING OF THE THIRD COLD FRONT IS A BIT IN QUESTION...BUT IT APPEARS THAT IT WILL ARRIVE EITHER SATURDAY OR SAT NIGHT. PRECIP CHANCES WILL INCREASE DURING THE FRONTAL PASSAGES...WHICH MEANS WE HAVE SEVERAL DAYS WITH A MENTION OF SHOWERS AND STORMS. SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT. THE DIURNAL CU FIELD SHOULD DISSIPATE TOWARD SUNSET...EXCEPT FOR IN OUR SOUTHEAST AREAS WHERE THE CU FIELD APPEARS MORE SYNOPTICALLY DRIVEN. AS THE COLD FRONT DROPS SOUTH ACROSS OUR COUNTIES TONIGHT... IT WILL BRING SOME LOWER DEWPOINT AIR WITH IT. HOWEVER...AS TEMPS DROP BEFORE THE DRY AIR ARRIVES, CAN NOT RULE OUT SOME PATCHY FOG AGAIN OVERNIGHT. CLOUDS ARE EXPECTED TO OVERSPREAD THE AREA FROM NW TO SE...SO THAT SHOULD PREVENT ANY DENSE FOG. MONDAY WILL CLOUDY AND COOLER CONDITIONS AS RAIN SHOWERS ADVANCE TOWARD IL ACROSS IOWA. HOWEVER...THE EASTWARD PROGRESSION OF RAIN WILL STALL OUT IN IOWA MON/MON NIGHT. WE SHOULD REMAIN DRY UNTIL LATER TUESDAY AFTERNOON AND TUESDAY NIGHT, AFTER A WARM FRONT LIFTS NORTHEAST ACROSS C IL. TUESDAY HIGHS WILL REBOUND ABOUT 10 DEGREES WARMER THAN MONDAY BEHIND THAT WARM FRONT. SHOWERS AND A FEW THUNDERSTORMS WILL INCREASE IN COVERAGE TUESDAY NIGHT...AS A BAND OF PRECIP ACCOMPANIES THE NEXT COLD FRONT MOVING SE ACROSS THE AREA. LONG TERM...WEDNESDAY THROUGH SUNDAY. THE COLD AIR WILL LAG A BIT ON WEDNESDAY...SO HIGHS ACROSS THE SOUTH MAY REACH THE MID 70S AGAIN...BUT NORTHERN AREAS MAY BE HELD DOWN IN THE UPPER 60S WITH FALLING TEMPS IN THE AFTERNOON. THURSDAY WILL BE OUR NEXT COOL DAY...AS HIGHS DROP 10-12 DEG BELOW WED HIGHS...WITH READINGS IN THE UPPER 50S NORTHEAST TO MID 60S SOUTHWEST. THE COLDEST AIR WILL REMAIN OFF TO OUR NORTHEAST. AS FOR THE FAR EXTENDED...THE ECMWF AND CANADIAN ARE STRONGER WITH THE LEADING CLIPPER LIKE SYSTEM FOR FRIDAY THAN THE GFS. THEN GFS BRINGS A COLD FRONT ON SATURDAY...WHILE THE ECMWF HOLDS IT OFF UNTIL LATE SATURDAY INTO SATURDAY NIGHT. STORMS WILL ACCOMPANY BOTH SYSTEMS...AS DYNAMICS LOOK FAVORABLE FOR STRONG UPDRAFTS. DRY WEATHER SHOULD RETURN SUNDAY AS COLD AIR PASSES BY JUST TO OUR NORTHEAST ONCE AGAIN. SHIMON && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTHERN INDIANA
918 PM EDT TUE MAR 27 2012 .UPDATE... SLIGHT MODIFICATIONS TO ONGOING FCST WRT DLAD TIMING OF PRECIP WITH SLOWER INITIATION NOW UNDERWAY FM NCNTL INTO WCNTL ILLINOIS. GIVEN INITIAL DOWNSTREAM/CWA DPS IN 30S...EXPECT CONVECTION TO REMAIN IN CLOSE PROXIMITY TO SFC FNTL BNDRY...AND TIMED LOW CHC POPS INLINE WITH HIGH RES BLEND WRF/RUC/HRRR. ADDITIONAL SLIGHT TWEAKS TO TEMP/DP/WIND TOWARD LATEST HRRR/LAV GUID. && .PREV DISCUSSION... /ISSUED 819 PM EDT TUE MAR 27 2012/ AVIATION... MAIN CONCERNS FOR THE PERIOD ARE TIMING/COVERAGE OF SHOWERS AND THUNDERSTORMS TONIGHT AND LLWS. LACK OF BOTH MOISTURE AND STRONG FORCING PLAGUE CONVECTIVE CHANCES IN NORTHERN INDIANA TONIGHT. DEWPOINTS ARE ONLY IN THE MIDDLE 30S ACROSS THE AREA...ALTHOUGH MIDDLE TO UPPER 50S DEWPOINTS CAN BE FOUND IN WESTERN ILLINOIS AND WILL ADVECT TOWARDS NORTHERN INDIANA TONIGHT. THIS THIN AREA OF INSTABILITY IS WHERE INITIAL ATTEMPTS AT CONVECTIVE INITIATION CAN BE SEEN AS AGITATED CU ON VIS SAT AND WEAK RETURNS ON KDVN RADAR. THIS WOULD SUPPORT HRRR AND LOCAL WRF GUIDANCE THAT BOTH SHOWED A BROKEN LINE OF CONVECTION FORMING AROUND 00Z AND STRENGTHENING THROUGH 03Z BEFORE WEAKENING AS IT MOVES EASTWARD. THIS LINE OF BROKEN SHOWERS/THUNDERSTORMS WILL REACH KSBN BETWEEN 04Z AND 07Z AND KFWA BETWEEN 05Z AND 09Z. WENT VCTS AT BOTH TERMINALS TO SHOW LACK OF CONFIDENCE SINCE STORMS WILL BE WEAKENING AS THEY MOVE CLOSER AND COVERAGE MAY BE SPARSE. INCREASING LOW LEVEL FLOW THROUGH THE LATE EVENING AND INTO THE OVERNIGHT HOURS REQUIRES A LLWS MENTION AT BOTH TAF SITES FOR SEVERAL HOURS TONIGHT. TOMORROW...GUSTY NORTHWEST WINDS WILL COMMENCE DURING THE MORNING HOURS AND CONTINUE THROUGHOUT MOST OF THE DAY. PREV DISCUSSION... /ISSUED 357 PM EDT TUE MAR 27 2012/ SHORT TERM... / TONIGHT THROUGH WEDNESDAY NIGHT / OPENING/FILLING UPPER LOW NOW NEAR THE ONTARIO/MINNESOTA BORDER WILL PROPAGATE EWD INTO THE NORTHERN GREAT LAKES TONIGHT. THIS WILL FORCE A WARM FRONT THROUGH THE FA THIS EVENING...FOLLOWED QUICKLY BY A COLD FRONT OVERNIGHT. THE MAIN FOCUS IS ON CHANCES FOR CONVECTION ALONG THE COLD FRONT TONIGHT AS A NARROW RIBBON OF DEEPER MOISTURE AND WEAK INSTABILITY WORKS IN JUST AHEAD/ALONG OF THIS FRONTAL BOUNDARY WITHIN A STRENGTHENING LLJ. LATEST HI-RES GUIDANCE HINTS AT THE CAP BREAKING AND DEEP MOIST CONVECTION DEVELOPING LATE THIS AFTN INTO THIS EVENING FROM NORTHERN MO INTO SE IA AND NRN IL WITHIN THIS NARROW WARM SECTOR...WITH STRONGER MID/UPPER LVL ASCENT / PER HEIGHT FALLS AND 7-3H Q-VECTOR CONVERGENCE / SUGGESTING THAT AT LEAST SCATTERED LOW TOPPED CONVECTION WILL DEVELOP THIS EVENING ACROSS NORTHERN/CENTRAL LOWER MI ALONG THE SYSTEM SFC OCCLUSION. STILL PLENTY OF UNCERTAINTY WRT WHETHER OR NOT THIS ACTIVITY FILLS IN OVER THE FA...AND TIMING. A COMBINATION OF LATER ARRIVAL OF DEEPER MOISTURE ALONG/AHEAD OF THE FRONT...AND UPTICK IN MID LEVEL ASCENT LATE WITH A PIVOTING 70 KT MID LVL JET MAX...SUPPORTS HIGHER POPS ACROSS THE SOUTHWEST LATER THIS EVENING AND EARLY OVERNIGHT...AND ACROSS THE SOUTHEAST LATER TONIGHT. SPC HAS THE IWX CWA IN GENERAL THUNDER WITH A FIVE PERCENT CHANCE OF SEVERE STORMS...BEST CHANCES BEFORE 06Z. DEEP SHEAR OF 40-50 KTS COMBINED WITH NARROWING MUCAPE PLUME AROUND 1000 J/KG SUPPORTS THIS VERY LOW RISK FOR HAIL/WIND. ON WEDNESDAY...DEEP POST FRONTAL MIXING IN DRY SLOT WILL PROMOTE DRY, WINDY, AND UNUSUALLY MILD WX. A BROKEN STRATO CU DECK COULD CLIP NORTHERN AREAS LATE IN THE DAY LIMITING MIXING/INSOLATION. LOW LEVEL RIDGING WILL BUILD INTO THE WESTERN GREAT LAKES WEDNESDAY NIGHT POSSIBLY BRINGING SOME PATCHY FROST TO NORTHERN AREAS. OPTED TO LEAVE ANY MENTION OF FROST OUT OF THE FCST FOR NOW GIVEN A LINGERING PRESSURE GRADIENT AND POTENTIAL FOR SCT/BKN STRATO CU DECK. LONG TERM...THURSDAY THROUGH TUESDAY COOLER CONDITIONS TO BEGIN THE LONG TERM PERIOD WITH NEAR NEUTRAL TEMPERATURE ADVECTION ANTICIPATED TUESDAY UNDER THE INFLUENCE OF LOW LEVEL RIDGE AXIS. RELATIVELY SHALLOW MIXING TO AROUND 2000 FT WOULD SUPPORT HIGHS GENERALLY IN THE LOWER TO MID 50S...ALTHOUGH COOLER FOR LAKESHORE AREAS IN THE UPPER 40S WHERE ONSHORE COMPONENT SHOULD PERSIST. BY THURSDAY NIGHT...MID LEVEL RIDGING WILL BEGIN TO BUILD ACROSS THE WESTERN GREAT LAKES AS A SOUTHWESTERLY LOW LEVEL JET STRENGTHENS ACROSS THE MID MS RIVER VALLEY. A STRONG LOW LEVEL THETAE GRADIENT WILL ACCOMPANY THE NOSE OF THIS LOW LEVEL JET...WITH AXIS OF STRONGER LOW LEVEL WARM/MOIST ADVECTION AND MOISTURE CONVERGENCE SHIFTING INTO FORECAST AREA DURING THE OVERNIGHT HOURS. FORECAST CHALLENGE AT THIS POINT IS RESOLVING TIMING OF SMALLER SCALE EMBEDDED UPPER LEVEL SHORT WAVES TO ENHANCE PRECIP CHANCES. FORECAST AREA WILL BECOME SUSCEPTIBLE TO THESE SMALLER SCALE EMBEDDED WAVES EJECTING DOWNSTREAM OF BROADER NEGATIVE UPPER LEVEL HEIGHT ANOMALY ACROSS WESTERN CONUS HOWEVER...AND FOLLOWED CONSENSUS/ENSEMBLE IDEA OF LOW CHANCE -TSRA POPS ACROSS THE WEST LATE THURSDAY NIGHT. OTHER CONCERN...WILL BE POSSIBILITY OF SOME PATCHY FROST ACROSS THE EAST WHERE WEAKER GRADIENT/DECOUPLING WILL PERSIST FOR MUCH OF THE NIGHT. HOWEVER...CONCERN NOW THAT MID/UPPER LEVEL CLOUDS MAY MOVE IN DURING THE OVERNIGHT HOURS TO LIMIT THIS POTENTIAL. WILL MAINTAIN THIS PATCHY FROST MENTION FOR NOW GIVEN A PERIOD OF STRONG RADIATIONAL COOLING EXPECTED AT LEAST DURING THE EVENING HOURS. FOR FRIDAY...HAVE CONTINUED THE UPWARD TREND IN POPS TO HIGH CHANCE...AS A SLIGHTLY MORE SUBSTANTIAL UPPER LEVEL VORT MAX SHIFTS INTO THE WESTERN GREAT LAKES. THIS WAVE DOES APPEAR TO BE IN A DAMPENING PHASE AS IT TRACKS ACROSS THE AREA...BUT MOISTURE AVAILABILITY SHOULD BE SUFFICIENT ENOUGH FOR SCATTERED SHOWERS AND EMBEDDED THUNDERSTORMS FRIDAY/FRIDAY EVENING. SEVERE POTENTIAL DOES NOT APPEAR TO BE VERY HIGH AT THIS TIME GIVEN LIMITED MID LEVEL LAPSE RATES...AND QUESTIONABLE POTENTIAL OF SFC BASED CONVECTION. FORECAST CONFIDENCE WITH POPS FOR THE WEEKEND REMAINS LOW DUE TO POTENTIAL OF SEVERAL SMALLER SCALE WAVES INFLUENCING THE AREA AND DIFFICULT TO LATCH ONTO POPS AT THIS TIME...UNTIL LATE SUNDAY WHEN MEDIUM RANGE MODELS ARE IN BETTER AGREEMENT IN MORE VIGOROUS UPPER TROUGH LIFTING INTO THE UPPER GREAT LAKES REGION FROM THE PLAINS. RUN TO RUN CONSISTENCE WITH EVOLUTION OF THIS TROUGH EARLY NEXT WEEK HAS BEEN VERY POOR WITH 12Z CONSENSUS MUCH FASTER THAN 00Z GUIDANCE. SYSTEM LIKELY TO BE IN OCCLUSION PHASE ACROSS THE GREAT LAKES REGION AND HAVE MAINTAINED CHANCE TSRA MONDAY/MONDAY NIGHT. UNSETTLED PATTERN TO CONTINUE TUESDAY AS COOL MID LEVEL POCKET INDUCES CONTINUED SHOWER CHANCES. IN TERMS OF TEMPS...MUCH ABOVE NORMAL TEMPS EXPECTED SUNDAY/MONDAY IN ADVANCE OF THE AMPLIFIED UPPER TROUGH...TRENDING BACK TO MID 50S TO 60 BY TUESDAY. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM...MARSILI LONG TERM...STEINWEDEL AVIATION...BENTLEY UPDATE...MURPHY
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
819 PM EDT TUE MAR 27 2012 .AVIATION... MAIN CONCERNS FOR THE PERIOD ARE TIMING/COVERAGE OF SHOWERS AND THUNDERSTORMS TONIGHT AND LLWS. LACK OF BOTH MOISTURE AND STRONG FORCING PLAGUE CONVECTIVE CHANCES IN NORTHERN INDIANA TONIGHT. DEWPOINTS ARE ONLY IN THE MIDDLE 30S ACROSS THE AREA...ALTHOUGH MIDDLE TO UPPER 50S DEWPOINTS CAN BE FOUND IN WESTERN ILLINOIS AND WILL ADVECT TOWARDS NORTHERN INDIANA TONIGHT. THIS THIN AREA OF INSTABILITY IS WHERE INITIAL ATTEMPTS AT CONVECTIVE INITIATION CAN BE SEEN AS AGITATED CU ON VIS SAT AND WEAK RETURNS ON KDVN RADAR. THIS WOULD SUPPORT HRRR AND LOCAL WRF GUIDANCE THAT BOTH SHOWED A BROKEN LINE OF CONVECTION FORMING AROUND 00Z AND STRENGTHENING THROUGH 03Z BEFORE WEAKENING AS IT MOVES EASTWARD. THIS LINE OF BROKEN SHOWERS/THUNDERSTORMS WILL REACH KSBN BETWEEN 04Z AND 07Z AND KFWA BETWEEN 05Z AND 09Z. WENT VCTS AT BOTH TERMINALS TO SHOW LACK OF CONFIDENCE SINCE STORMS WILL BE WEAKENING AS THEY MOVE CLOSER AND COVERAGE MAY BE SPARSE. INCREASING LOW LEVEL FLOW THROUGH THE LATE EVENING AND INTO THE OVERNIGHT HOURS REQUIRES A LLWS MENTION AT BOTH TAF SITES FOR SEVERAL HOURS TONIGHT. TOMORROW...GUSTY NORTHWEST WINDS WILL COMMENCE DURING THE MORNING HOURS AND CONTINUE THROUGHOUT MOST OF THE DAY. .PREV DISCUSSION... /ISSUED 357 PM EDT TUE MAR 27 2012/ SHORT TERM... / TONIGHT THROUGH WEDNESDAY NIGHT / OPENING/FILLING UPPER LOW NOW NEAR THE ONTARIO/MINNESOTA BORDER WILL PROPAGATE EWD INTO THE NORTHERN GREAT LAKES TONIGHT. THIS WILL FORCE A WARM FRONT THROUGH THE FA THIS EVENING...FOLLOWED QUICKLY BY A COLD FRONT OVERNIGHT. THE MAIN FOCUS IS ON CHANCES FOR CONVECTION ALONG THE COLD FRONT TONIGHT AS A NARROW RIBBON OF DEEPER MOISTURE AND WEAK INSTABILITY WORKS IN JUST AHEAD/ALONG OF THIS FRONTAL BOUNDARY WITHIN A STRENGTHENING LLJ. LATEST HI-RES GUIDANCE HINTS AT THE CAP BREAKING AND DEEP MOIST CONVECTION DEVELOPING LATE THIS AFTN INTO THIS EVENING FROM NORTHERN MO INTO SE IA AND NRN IL WITHIN THIS NARROW WARM SECTOR...WITH STRONGER MID/UPPER LVL ASCENT / PER HEIGHT FALLS AND 7-3H Q-VECTOR CONVERGENCE / SUGGESTING THAT AT LEAST SCATTERED LOW TOPPED CONVECTION WILL DEVELOP THIS EVENING ACROSS NORTHERN/CENTRAL LOWER MI ALONG THE SYSTEM SFC OCCLUSION. STILL PLENTY OF UNCERTAINTY WRT WHETHER OR NOT THIS ACTIVITY FILLS IN OVER THE FA...AND TIMING. A COMBINATION OF LATER ARRIVAL OF DEEPER MOISTURE ALONG/AHEAD OF THE FRONT...AND UPTICK IN MID LEVEL ASCENT LATE WITH A PIVOTING 70 KT MID LVL JET MAX...SUPPORTS HIGHER POPS ACROSS THE SOUTHWEST LATER THIS EVENING AND EARLY OVERNIGHT...AND ACROSS THE SOUTHEAST LATER TONIGHT. SPC HAS THE IWX CWA IN GENERAL THUNDER WITH A FIVE PERCENT CHANCE OF SEVERE STORMS...BEST CHANCES BEFORE 06Z. DEEP SHEAR OF 40-50 KTS COMBINED WITH NARROWING MUCAPE PLUME AROUND 1000 J/KG SUPPORTS THIS VERY LOW RISK FOR HAIL/WIND. ON WEDNESDAY...DEEP POST FRONTAL MIXING IN DRY SLOT WILL PROMOTE DRY, WINDY, AND UNUSUALLY MILD WX. A BROKEN STRATO CU DECK COULD CLIP NORTHERN AREAS LATE IN THE DAY LIMITING MIXING/INSOLATION. LOW LEVEL RIDGING WILL BUILD INTO THE WESTERN GREAT LAKES WEDNESDAY NIGHT POSSIBLY BRINGING SOME PATCHY FROST TO NORTHERN AREAS. OPTED TO LEAVE ANY MENTION OF FROST OUT OF THE FCST FOR NOW GIVEN A LINGERING PRESSURE GRADIENT AND POTENTIAL FOR SCT/BKN STRATO CU DECK. LONG TERM...THURSDAY THROUGH TUESDAY COOLER CONDITIONS TO BEGIN THE LONG TERM PERIOD WITH NEAR NEUTRAL TEMPERATURE ADVECTION ANTICIPATED TUESDAY UNDER THE INFLUENCE OF LOW LEVEL RIDGE AXIS. RELATIVELY SHALLOW MIXING TO AROUND 2000 FT WOULD SUPPORT HIGHS GENERALLY IN THE LOWER TO MID 50S...ALTHOUGH COOLER FOR LAKESHORE AREAS IN THE UPPER 40S WHERE ONSHORE COMPONENT SHOULD PERSIST. BY THURSDAY NIGHT...MID LEVEL RIDGING WILL BEGIN TO BUILD ACROSS THE WESTERN GREAT LAKES AS A SOUTHWESTERLY LOW LEVEL JET STRENGTHENS ACROSS THE MID MS RIVER VALLEY. A STRONG LOW LEVEL THETAE GRADIENT WILL ACCOMPANY THE NOSE OF THIS LOW LEVEL JET...WITH AXIS OF STRONGER LOW LEVEL WARM/MOIST ADVECTION AND MOISTURE CONVERGENCE SHIFTING INTO FORECAST AREA DURING THE OVERNIGHT HOURS. FORECAST CHALLENGE AT THIS POINT IS RESOLVING TIMING OF SMALLER SCALE EMBEDDED UPPER LEVEL SHORT WAVES TO ENHANCE PRECIP CHANCES. FORECAST AREA WILL BECOME SUSCEPTIBLE TO THESE SMALLER SCALE EMBEDDED WAVES EJECTING DOWNSTREAM OF BROADER NEGATIVE UPPER LEVEL HEIGHT ANOMALY ACROSS WESTERN CONUS HOWEVER...AND FOLLOWED CONSENSUS/ENSEMBLE IDEA OF LOW CHANCE -TSRA POPS ACROSS THE WEST LATE THURSDAY NIGHT. OTHER CONCERN...WILL BE POSSIBILITY OF SOME PATCHY FROST ACROSS THE EAST WHERE WEAKER GRADIENT/DECOUPLING WILL PERSIST FOR MUCH OF THE NIGHT. HOWEVER...CONCERN NOW THAT MID/UPPER LEVEL CLOUDS MAY MOVE IN DURING THE OVERNIGHT HOURS TO LIMIT THIS POTENTIAL. WILL MAINTAIN THIS PATCHY FROST MENTION FOR NOW GIVEN A PERIOD OF STRONG RADIATIONAL COOLING EXPECTED AT LEAST DURING THE EVENING HOURS. FOR FRIDAY...HAVE CONTINUED THE UPWARD TREND IN POPS TO HIGH CHANCE...AS A SLIGHTLY MORE SUBSTANTIAL UPPER LEVEL VORT MAX SHIFTS INTO THE WESTERN GREAT LAKES. THIS WAVE DOES APPEAR TO BE IN A DAMPENING PHASE AS IT TRACKS ACROSS THE AREA...BUT MOISTURE AVAILABILITY SHOULD BE SUFFICIENT ENOUGH FOR SCATTERED SHOWERS AND EMBEDDED THUNDERSTORMS FRIDAY/FRIDAY EVENING. SEVERE POTENTIAL DOES NOT APPEAR TO BE VERY HIGH AT THIS TIME GIVEN LIMITED MID LEVEL LAPSE RATES...AND QUESTIONABLE POTENTIAL OF SFC BASED CONVECTION. FORECAST CONFIDENCE WITH POPS FOR THE WEEKEND REMAINS LOW DUE TO POTENTIAL OF SEVERAL SMALLER SCALE WAVES INFLUENCING THE AREA AND DIFFICULT TO LATCH ONTO POPS AT THIS TIME...UNTIL LATE SUNDAY WHEN MEDIUM RANGE MODELS ARE IN BETTER AGREEMENT IN MORE VIGOROUS UPPER TROUGH LIFTING INTO THE UPPER GREAT LAKES REGION FROM THE PLAINS. RUN TO RUN CONSISTENCE WITH EVOLUTION OF THIS TROUGH EARLY NEXT WEEK HAS BEEN VERY POOR WITH 12Z CONSENSUS MUCH FASTER THAN 00Z GUIDANCE. SYSTEM LIKELY TO BE IN OCCLUSION PHASE ACROSS THE GREAT LAKES REGION AND HAVE MAINTAINED CHANCE TSRA MONDAY/MONDAY NIGHT. UNSETTLED PATTERN TO CONTINUE TUESDAY AS COOL MID LEVEL POCKET INDUCES CONTINUED SHOWER CHANCES. IN TERMS OF TEMPS...MUCH ABOVE NORMAL TEMPS EXPECTED SUNDAY/MONDAY IN ADVANCE OF THE AMPLIFIED UPPER TROUGH...TRENDING BACK TO MID 50S TO 60 BY TUESDAY. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM...STEINWEDEL LONG TERM...MARSILI AVIATION...BENTLEY
AREA FORECAST DISCUSSION
NWS DES MOINES IA
728 PM CDT TUE MAR 27 2012 .UPDATE PUBLIC DISCUSSION... .SHORT TERM /TONIGHT/... REMOVED ADV FROM AFD...REST OF FORECAST LOOKS ON TRACK. /REV .PREVIOUS SHORT TERM /TONIGHT/... SFC TROUGH AXIS ASSOCIATED WITH NORTHERN MINNESOTA LOW PRESSURE IS EXTENDING SOUTH THROUGH CNTRL IA THIS AFTERNOON. AIRMASS BEHIND THE TROUGH HAS DOWNSLOPE PROPERTIES INITIALLY REMAINING MILD YET MUCH DRIER WITH DEWPOINTS IN THE 30S ADVECTING IN. DEWPOINTS REMAIN IN THE MID TO UPPER 50S OVER THE SOUTHEAST IN ADVANCE OF THE SYSTEM. UPPER PV ANOMALY OVER SRN SOUTH DAKOTA WILL TRACK EAST AND WILL BE OVER FAR SOUTH CENTRAL MINNESOTA BY 00Z. SOME ASSOCIATED KINEMATIC FORCING WILL OCCUR TO THE SOUTHEAST OF THE SYSTEM. CURRENTLY INSTABILITY HAS BEEN INCREASING OVER THE SOUTHEAST THIRD OF THE WARNING AREA. RUC AND NAM PROXIMITY SOUNDINGS SHOW A WEAK CAP LOCATED NEAR 750 MB WHICH DOES NOT ERODE UNTIL AFTER 23Z WITH THE ARRIVAL OF MID LEVEL COOLING AND KINEMATICS WITH THE MID LEVEL WAVE. POSSIBLE A STORM OR TWO MAY FIRE OVER THE FAR SOUTHEAST BUT OVERALL THE CURRENT INSTABILITY IS NOT EXPECTED TO BE REALIZED UNTIL IT PUSHES SOUTHEAST OF THE STATE. A FEW SITES NEAR WIND ADVISORY CRITERIA ATTM MOMENT THOUGH OVERALL MOST ARE BELOW. HAVE TRIMMED PORTIONS OF THE ADVISORY BUT HAVE KEPT THE NORTH TO KEEP COLLABORATED WITH SURROUNDING SITES. HAVE MOVED END TIME UP TO 7 PM WITH WINDS DIMINISHING WITH THE LOSS OF DAY TIME HEATING AND MIXING. .LONG TERM /WEDNESDAY THROUGH TUESDAY/... TWO PRIMARY SYSTEMS TO CONTEND WITH IN THIS PERIOD. WEAK RIDGE APPROACHING THE MO VALLEY PRECEDING SHORT WAVE EJECTING OUT OF CURRENT EAST PACIFIC LONG WAVE THROUGH. THIS WAVE SHOULD REACH THE HIGH PLAINS LATE TOMORROW WHICH...COMBINED WITH THE DEPARTING RIDGE...WILL INCREASE WARM ADVECTION INTO THE MO VALLEY. THETA-E ADVECTION ADVANCES INTO SWRN IA COINCIDENT WITH ELEVATED CAPE GRADIENT. ALTHOUGH BEST ISENTROPIC LIFT WILL REMAIN NW INTO THE DAKOTAS AND ERN MN...MODEL 300K SURFACES NEAR INVERSION TOP SUGGEST THERE WILL BE SUFFICIENT LIFT AND SATURATION EARLY THU MORNING FOR CONVECTION TO DEVELOP AND LINGER INTO THE MORNING. ATTENTION THEN TURNS UPSTREAM WHERE BOTH NAM AND GFS DEPICT 1500-2500 J/KG MLCAPES BECOMING UNCAPPED JUST WEST OF MO RIVER DURING PEAK HEATING. LOW LEVEL CONVERGENCE IS SOMEWHAT WEAK...BUT THIS FAVORABLE THERMODYNAMIC ENVIRONMENT AIDED BY LARGE SCALE FORCING WITH WAVE SHOULD BE SUFFICIENT FOR A MCS TO DEVELOP AND THEN LIKELY WEAKEN INTO THE EVENING WITH LOSS OF HEATING. REGARDING SEVERE POTENTIAL DURING EVENT...ELEVATED NATURE AND FAIRLY WEAK UNIDIRECTIONAL FLOW IN EFFECTIVE INFLOW LAYER EARLY THU SHOULD DIMINISH THIS SEVERE POTENTIAL. MOST LIKELY SEVERE CHANCES LOOK TO BE DURING PEAK HEATING TAPPING BETTER 0-6KM SHEAR LATE AFTERNOON AND EVENING WHEN AND IF CONVECTION BECOMES SURFACE BASED. WEAK NORTHERN STREAM WAVE HAS RESULTED IN SLIGHT CHANCES FRI NIGHT WITH NEXT LARGE SYSTEM IN THE OFFING EARLY NEXT WEEK. MODELS HAVE COME INTO SOMEWHAT BETTER AGREEMENT WITH RESPECT TO TIMING SUGGESTING FORCING INCREASING SUN NIGHT FOLLOWED BY FRONTAL PASSAGE LATE SUNDAY AFTERNOON OR SUNDAY NIGHT. BEST SHEAR SEEMS TO REMAIN TO OUR SOUTH AND INSTABILITY IS UNREMARKABLE AT THIS POINT SO DO NOT SEE ELEVATED SEVERE THREAT WITH THIS SYSTEM AT THE MOMENT. DIRTY NW FLOW WILL KEPT LOW CHANCES GOING IN ITS WAKE THROUGH TUE. TEMPS WILL DROP SHARPLY BEHIND THIS...BUT ONLY DOWN TO ABOUT CLIMO. NO FREEZING TEMPS OR FROST ANTICIPATED THROUGH DAY 7. && .AVIATION...28/00Z FRONT QUICKLY MAKING ITS WAY EAST THIS EVENING WITH BRISK WEST TO SOUTHWEST WINDS CONTINUING BEHIND THE BOUNDARY. CIGS REMAIN VFR WITH SCT070 TO BKN150 EXPECTED NEAR FEW HOURS ACROSS THE REGION. MIXING WILL DIMINISH RAPIDLY AFT 00Z AND EXPECT WINDS TO RELAX QUICKLY INTO THE 01Z HOUR. BY 15Z WED MIXING WILL AGAIN INCREASE WITH GUSTS TO 20 TO 25KTS NORTH DURING THROUGH THE AFTERNOON. SCT TO BKN MID LEVEL CLOUDS TO RETURN LATE IN THE PERIOD WITH VERY LIGHT WINDS. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE && $$ SHORT TERM...DONAVON/REV AVIATION...REV LONG TERM...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
624 PM CDT TUE MAR 27 2012 .UPDATE 28/00Z AVIATION DISCUSSION... .SHORT TERM /TONIGHT/... SFC TROUGH AXIS ASSOCIATED WITH NORTHERN MINNESOTA LOW PRESSURE IS EXTENDING SOUTH THROUGH CNTRL IA THIS AFTERNOON. AIRMASS BEHIND THE TROUGH HAS DOWNSLOPE PROPERTIES INITIALLY REMAINING MILD YET MUCH DRIER WITH DEWPOINTS IN THE 30S ADVECTING IN. DEWPOINTS REMAIN IN THE MID TO UPPER 50S OVER THE SOUTHEAST IN ADVANCE OF THE SYSTEM. UPPER PV ANOMALY OVER SRN SOUTH DAKOTA WILL TRACK EAST AND WILL BE OVER FAR SOUTH CENTRAL MINNESOTA BY 00Z. SOME ASSOCIATED KINEMATIC FORCING WILL OCCUR TO THE SOUTHEAST OF THE SYSTEM. CURRENTLY INSTABILITY HAS BEEN INCREASING OVER THE SOUTHEAST THIRD OF THE WARNING AREA. RUC AND NAM PROXIMITY SOUNDINGS SHOW A WEAK CAP LOCATED NEAR 750 MB WHICH DOES NOT ERODE UNTIL AFTER 23Z WITH THE ARRIVAL OF MID LEVEL COOLING AND KINEMATICS WITH THE MID LEVEL WAVE. POSSIBLE A STORM OR TWO MAY FIRE OVER THE FAR SOUTHEAST BUT OVERALL THE CURRENT INSTABILITY IS NOT EXPECTED TO BE REALIZED UNTIL IT PUSHES SOUTHEAST OF THE STATE. A FEW SITES NEAR WIND ADVISORY CRITERIA ATTM MOMENT THOUGH OVERALL MOST ARE BELOW. HAVE TRIMMED PORTIONS OF THE ADVISORY BUT HAVE KEPT THE NORTH TO KEEP COLLABORATED WITH SURROUNDING SITES. HAVE MOVED END TIME UP TO 7 PM WITH WINDS DIMINISHING WITH THE LOSS OF DAY TIME HEATING AND MIXING. .LONG TERM /WEDNESDAY THROUGH TUESDAY/... TWO PRIMARY SYSTEMS TO CONTEND WITH IN THIS PERIOD. WEAK RIDGE APPROACHING THE MO VALLEY PRECEDING SHORT WAVE EJECTING OUT OF CURRENT EAST PACIFIC LONG WAVE THROUGH. THIS WAVE SHOULD REACH THE HIGH PLAINS LATE TOMORROW WHICH...COMBINED WITH THE DEPARTING RIDGE...WILL INCREASE WARM ADVECTION INTO THE MO VALLEY. THETA-E ADVECTION ADVANCES INTO SWRN IA COINCIDENT WITH ELEVATED CAPE GRADIENT. ALTHOUGH BEST ISENTROPIC LIFT WILL REMAIN NW INTO THE DAKOTAS AND ERN MN...MODEL 300K SURFACES NEAR INVERSION TOP SUGGEST THERE WILL BE SUFFICIENT LIFT AND SATURATION EARLY THU MORNING FOR CONVECTION TO DEVELOP AND LINGER INTO THE MORNING. ATTENTION THEN TURNS UPSTREAM WHERE BOTH NAM AND GFS DEPICT 1500-2500 J/KG MLCAPES BECOMING UNCAPPED JUST WEST OF MO RIVER DURING PEAK HEATING. LOW LEVEL CONVERGENCE IS SOMEWHAT WEAK...BUT THIS FAVORABLE THERMODYNAMIC ENVIRONMENT AIDED BY LARGE SCALE FORCING WITH WAVE SHOULD BE SUFFICIENT FOR A MCS TO DEVELOP AND THEN LIKELY WEAKEN INTO THE EVENING WITH LOSS OF HEATING. REGARDING SEVERE POTENTIAL DURING EVENT...ELEVATED NATURE AND FAIRLY WEAK UNIDIRECTIONAL FLOW IN EFFECTIVE INFLOW LAYER EARLY THU SHOULD DIMINISH THIS SEVERE POTENTIAL. MOST LIKELY SEVERE CHANCES LOOK TO BE DURING PEAK HEATING TAPPING BETTER 0-6KM SHEAR LATE AFTERNOON AND EVENING WHEN AND IF CONVECTION BECOMES SURFACE BASED. WEAK NORTHERN STREAM WAVE HAS RESULTED IN SLIGHT CHANCES FRI NIGHT WITH NEXT LARGE SYSTEM IN THE OFFING EARLY NEXT WEEK. MODELS HAVE COME INTO SOMEWHAT BETTER AGREEMENT WITH RESPECT TO TIMING SUGGESTING FORCING INCREASING SUN NIGHT FOLLOWED BY FRONTAL PASSAGE LATE SUNDAY AFTERNOON OR SUNDAY NIGHT. BEST SHEAR SEEMS TO REMAIN TO OUR SOUTH AND INSTABILITY IS UNREMARKABLE AT THIS POINT SO DO NOT SEE ELEVATED SEVERE THREAT WITH THIS SYSTEM AT THE MOMENT. DIRTY NW FLOW WILL KEPT LOW CHANCES GOING IN ITS WAKE THROUGH TUE. TEMPS WILL DROP SHARPLY BEHIND THIS...BUT ONLY DOWN TO ABOUT CLIMO. NO FREEZING TEMPS OR FROST ANTICIPATED THROUGH DAY 7. && .AVIATION...28/00Z FRONT QUICKLY MAKING ITS WAY EAST THIS EVENING WITH BRISK WEST TO SOUTHWEST WINDS CONTINUING BEHIND THE BOUNDARY. CIGS REMAIN VFR WITH SCT070 TO BKN150 EXPECTED NEAR FEW HOURS ACROSS THE REGION. MIXING WILL DIMINISH RAPIDLY AFT 00Z AND EXPECT WINDS TO RELAX QUICKLY INTO THE 01Z HOUR. BY 15Z WED MIXING WILL AGAIN INCREASE WITH GUSTS TO 20 TO 25KTS NORTH DURING THROUGH THE AFTERNOON. SCT TO BKN MID LEVEL CLOUDS TO RETURN LATE IN THE PERIOD WITH VERY LIGHT WINDS. && .DMX WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY UNTIL 7 PM EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN- WEBSTER-HAMILTON- && $$ SHORT TERM/AVIATION...DONAVON LONG TERM...SMALL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1153 PM CDT SUN MAR 25 2012 .AVIATION... CIGS EXPECTED TO LOWER INTO MVFR RANGE OVRNGT AND MON MORNING AS COLD MOIST AIR ADVECTS IN FROM LAKE MICHIGAN. POTENTIAL EXISTS FOR IFR CIGS ESPECIALLY NEAR MISSISSIPPI RVR TOWARD DAYBREAK AND THROUGH MID AM MON ALONG WITH PATCHY FOG AND DRIZZLE WITH VSBYS 2-6SM. AREA OF SHOWERS OVER MN WILL DRIFT E/SE AND MAY AFFECT PORTIONS OF NE IA AND ESPECIALLY NW IL LATE TNGT THROUGH MON AM. DBQ TERMINAL LOOKS TO BE ON THE EDGE OF FORCING AND HAVE GONE WITH VCSH FOR NOW AND LET LATER SHIFTS ADJUST AS NEEDED. WINDS WILL SHIFT TO THE EAST AND INCREASE TO 15-20 KTS WITH HIGHER GUSTS AROUND 25 KTS OVRNGT AND REMAIN SO THROUGH REST OF TAF CYCLE. EXPECT CIGS TO CLIMB INTO VFR DURING THE AFTN AND REMAIN VFR THROUGH MON EVE. && .PREV DISCUSSION... /ISSUED 950 PM CDT SUN MAR 25 2012/ UPDATE... AREA OF SHOWERS AND ISOLD TSTMS OVER WESTERN MN OCCURRING IN ZONE OF ELEVATED WARM ADVECTION AND THETA-E CONVERGENCE IN 850-700 MB LAYERS. 00Z NAM SHOWS WARM ADVECTION AND THETA-E CONVERGENCE INCREASING OVRNGT IN AREAS MAINLY N/NE OF QUAD CITIES. SOME OF THE MOST RECENT RUNS OF HRRR AND RUC BACKUP MODELS HAVE BEEN SHOWING PCPN COMING INTO NORTH... ALBEIT SLOW ON TRENDS. HAVE GONE AHEAD AND ADDED POPS TO AREAS NORTH OF QUAD CITIES OVRNGT AND MADE SOME ADJUSTMENTS TO POPS MON. UPDATED GRIDS AND ZFP OUT SHORTLY. && PREV DISCUSSION... /ISSUED 311 PM CDT SUN MAR 25 2012/ SYNOPSIS... THE MORNING UA ANALYSIS HAD AN UPPER RIDGE OVER THE PLAINS WITH A S/W OVER LAKE SUPERIOR. THE COLD FRONT TRAILING THE S/W WAS NOT EVIDENT IN THE SURFACE WIND/PRESSURE FIELDS AT 18Z HOWEVER THERE WAS A NICE THERMAL GRADIENT ALONG THE SOUTHERN EDGE OF THE TRAILING NORTHERN PLAINS HIGH PRESSURE RIDGE. THE 18Z ANALYSIS SHOWED 70 PLUS TEMPS AS FAR NORTH AS KDBQ AND TEMPS AROUND 60 IN NORTHEAST IA AND SOURTHEASTERN MN. SHORT TERM...TONIGHT AND MONDAY... THE LOW LEVEL FLOW WILL TURN MORE EASTERLY OVERNIGHT AS THE NORTHERN PLAINS SURFACE RIDGE SLIDES SOUTHEAST INTO THE GREAT LAKES. THE EASTERLY FLOW WILL BRING MUCH COOLER AIR INTO THE REGION FOR LATE TONIGHT AND MONDAY. EXPECT CLOUDS TO INCREASE LATE THIS EVENING AND OVERNIGHT AS LOW LEVELS COOL AND SATURATE. MID CLOUDS WILL ALSO SPREAD OVER THE AREA AFTER MIDNIGHT WITH INCREASING MID LEVEL WAA. FORCING OVERNIGHT DOES NOT LOOK THAT STRONG SO KEPT THE FORECAST DRY. THERE IS SOME POTENTIAL FOR DRIZZLE WITH THE ARRIVAL OF THE MOIST LOW LEVEL AIR OFF LAKE MI...BUT FORECAST SOUNDINGS WERE SHOWING A FAIRLY DEEP SATURATED LAYER WHICH ISN/T FAVORABLE FOR DRIZZLE. SOME LOW POPS WERE INCLUDED FOR MONDAY WHEN LOW AND MID LEVEL FGEN SPREADS SOUTHEAST THROUGH NORTHEASTERN CWFA. LOWS TONIGHT WILL BE CONSIDERABLY COLDER THAN WHAT THE REGION HAS EXPERIENCED THE LAST COUPLE OF WEEKS WITH MID TO UPPER 30S EXPECTED IN THE NORTHEASTERN CWFA. IT/S QUESTIONABLE IF THE COLDER AIR WILL REACH THE SOUTHWEST CWFA BY MORNING SO KEPT MINS THERE IN THE LOWER 50S. MONDAY TEMPERATURES OVER THE NORTHEASTERN HALF OF THE CWFA WILL NOT REBOUND MUCH WITH STRONG EASTERLY WINDS...CLOUDS AND POSSIBLY SOME RAIN SHOWERS SO KEPT HIGHS IN THE MID 40S WHILE THE SOUTHWEST HAS THE POTENTIAL TO SEE HIGHS IN THE LOW TO MID 60S. ..DLF.. LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY... TUESDAY WILL BE ANOTHER WARM AND BREEZY DAY WITH SCATTERED THUNDERSTORMS ALONG AND AHEAD OF A PASSING COLD FRONT. SLIGHTLY COOLER...BUT CONTINUED ABOVE NORMAL...TEMPERATURES TO THEN FOLLOW THROUGH MUCH OF THE WORKWEEK. RIDGE AT THE SURFACE AND ALOFT WILL FAVOR DRY CONDITIONS...FOLLOWED BY INCREASINGLY UNSETTLED WEATHER FRIDAY THROUGH NEXT WEEKEND AS THE THE UPPER FLOW BECOMES MORE AMPLIFIED. MONDAY NIGHT...VERY STRONG LOW LEVEL JET...WITH 850 WINDS PROGGED FROM 50 TO 70 KTS...IS SHOWN SURGING GULF MOISTURE FROM THE SOUTHERN PLAINS INTO THE UPPER MS VALLEY OUT AHEAD OF LOW PRESSURE DEVELOPING IN THE NORTHERN PLAINS. WHILE THIS IS DIRECTED WELL TO OUR WEST...THERE REMAINS A LOW POTENTIAL FOR STRAY ELEVATED WARM AIR ADVECTION SHOWERS OVER THE ESPECIALLY THE NORTHERN HALF OF THE FORECAST AREA...AND ALSO POSSIBLY OF MORE ORGANIZED SHOWERS OR AN ISOLATED THUNDERSTORMS ON THE EDGE OF THE STEEPER MID LEVEL LAPSE RATES TO OUR WEST TO WANDER INTO EASTERN IA TOWARD MORNING. WILL KEEP SLIGHT TO LOW CHANCE POPS ACROSS THE NORTH TO COVER THIS. OTHERWISE...THE DEEPENING LOW OVER THE NORTHERN PLAINS WILL PROVIDE A TIGHTENING PRESSURE GRADIENT AND BRISK SOUTHEAST TO SOUTH WINDS OVERNIGHT UNDER MOSTLY CLOUDY SKIES. UNTIL A SOMEWHAT DIFFUSE SURFACE WARM FRONT DEVELOPS AND SPREADS NORTHEAST INTO THE FORECAST AREA TOWARD MORNING...THE RELATIVELY DRY LOW LEVEL SOUTHEAST FLOW OUT OF THE RIDGE WILL HOLD TEMPERATURES IN THE 40S NORTH TO LOWER 50S SOUTH THROUGH THE NIGHT. TUESDAY...THE ASSOCIATED COLD FRONT SWEEPS THROUGH FROM LATE MORNING THROUGH MID AFTERNOON. LATEST MODELS DEPICT A GREAT DEAL OF MOISTURE AT OR BELOW 850 MB AND HAVE GONE WITH MOSTLY CLOUDY SKIES. EVEN WITH THE CLOUD COVER...LOW LEVEL WARM ADVECTION ON 15 TO 25 MPH SOUTH WINDS AHEAD OF THE FRONT SHOULD RESULT IN HIGHS WELL INTO THE 70S OVER ALL BUT THE FAR NORTHEAST. THIS WARMING...COMBINED WITH DEWPOINTS PUSHING INTO THE UPPER 50S IS SHOWN BY THE NAM RESULTING IN MUCAPES IN THE RANGE OF 1000 TO 1500 J/KG. THIS...COMBINED WITH 30 TO 40 KTS OF SURFACE TO 6 KM SPEED SHEAR WITH VEERING PROFILES... MAY BE FAVORABLE FOR A FEW LOW END SEVERE STORMS...ESPECIALLY ALONG AND EAST OF THE MS RIVER IN THE AFTERNOON...AND THE CURRENT SPC DAY 3 OUTLOOK HAS A SLIGHT RISK OVER OUR SE COUNTIES. ANTICIPATED COVERAGE OF SHOWERS AND THUNDERSTORMS SUPPORTS POPS IN A 30 TO 40 PERCENT RANGE. THE BACK EDGE OF ANY SHOWERS ALONG TO BEHIND THE FRONT MAY BE ON-GOING AT 00Z OVER THE FAR EAST AND WILL KEEP SLIGHT CHANCES GOING THERE INTO TUE EVENING. UPPER LEVEL RIDGE AND SURFACE HIGH PRESSURE PROVIDES DRY WEATHER WITH TEMPERATURES STILL ROUGHLY 10 DEGREES ABOVE NORMAL FOR WED INTO THU. WED NIGHT MAY SEE LOWS IN THE UPPER 30S IN THE FAR NORTH AS THE RIDGE AXIS PASSES OVERHEAD. THE COLDEST MOS GUIDANCE...THE MEN FROM THE 00Z RUN...INDICATES POCKETS OF MID 30S OVER EAST CENTRAL IA INTO NW IL. WILL CONTINUE TO WATCH THIS TREND...BUT HAVE KEPT TEMPERATURES CLOSER TO A CONSENSUS FOR NOW WITH MINS FROM THE UPPER 30S ALONG THE HIGHWAY 20 CORRIDOR TO THE MID 40S ACROSS THE SOUTH. POPS RETURN TO THE FORECAST FOR RAIN AND THUNDERSTORM CHANCES THU NIGHT INTO FRIDAY AS A WEAK SHORTWAVE TROUGH IS SHOWN SENDING A WEAK SURFACE LOW THROUGH KS TO CENTRAL IL. FORECAST CONFIDENCE REMAINS LOW BEYOND AS THERE CONTINUE TO BE SIGNIFICANT DIFFERENCES IN HOW THE MEDIUM RANGE MODELS HANDLE ENSUING SHORTWAVES...RESULTING IN AN EXTENDED PERIOD OF LOW END CHANCE POPS FRIDAY THROUGH SUNDAY THAT WILL LIKELY BECOME DEFINED IN LATER FORECASTS. ..SHEETS.. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
852 PM MDT TUE MAR 27 2012 .UPDATE... ISSUED AT 848 PM MDT TUE MAR 27 2012 JUST COMPLETED AN UPDATE. ADJUSTED CLOUD COVER BEST ON LATEST SATELLITE MODEL DATA. MODELS HAVE BACKED OFF ON THE CLOUD COVER THE REST OF THE NIGHT AND DECREASED. LATEST HRRR BRINGS SOME FOG CLOSE TO THE SOUTHERN PORTION OF THE FORECAST AREA. INSERTED PATCHY FOG IN THIS AREA FROM 09Z TO 14Z. ADJUSTED THE DEWPOINTS/WINDS PER LATEST RUC/HRRR. 00Z SOUNDINGS AND NAM WOULD INDICATE THAT EVEN THOUGH THERE IS ELEVATED INSTABILITY...THE SOUNDINGS ARE VERY VERY DRY AND CAPPED ALOFT. SO LEFT ANY MENTION OF THUNDERSTORMS THE REST OF THE NIGHT. UPDATE ISSUED AT 536 PM MDT TUE MAR 27 2012 CANCELLED RED FLAG WARNING EARLY AS WINDS HAVE DROPPED OFF DRAMATICALLY. CURRENTLY RATHER THICK HIGH LEVEL CLOUD COVER IS DRAPED ACROSS THE AREA. THIS IS BEING CAUSE BY RIGHT REAR QUADRANT OF MID/UPPER JET THAT REMAINS/MOVES ACROSS THE AREA THROUGH MOST OF THE NIGHT. SO INCREASED CLOUD COVER...ESPECIALLY FOR THIS EVENING. WIND FIELD IS RATHER LIGHT RIGHT NOW WITH RUC/HRRR CATCHING THE WIND FIELD NICELY SO ADJUSTED USING THEM. SOMETHING TO WATCH FOR LATER TONIGHT. THERE WILL BE A RIGHT REAR QUADRANT OF THE JET NEAR THE EASTERN PORTION OF THE FORECAST AREA WITH AN APPROACHING SHORTWAVE TROUGH. MODELS SHOWING A RATHER HIGH AMOUNT OF ELEVATED INSTABILITY. HOWEVER...THE CINH LOOKS STRONG BUT WITH SOME POCKETS OF WEAKNESS. QUESTION WILL THERE BE ENOUGH MOISTURE IN THE COLUMN TO GET THIS FULLY REALIZED. WILL CONTINUE TO WATCH THROUGH THE EVENING AND LOOK AT LATEST MODEL DATA/00Z SOUNDINGS TO SEE IF NEED TO ADD SOME THUNDERSTORMS FOR LATER TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 200 PM MDT TUE MAR 27 2012 WEAK UPPER LEVEL RIDGING WILL OCCUR ACROSS THE CENTRAL PLAINS TONIGHT AND WEDNESDAY BEFORE SEVERAL WEAK SHORT WAVE TROUGHS FLATTEN IT OUT WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL CONTINUE UNSEASONABLY MILD FOR LATE MARCH UNDER THIS REGIME. THE WEAK COLD FRONT WHICH PASSED THROUGH THE AREA LAST NIGHT IS APPROACHING THE WICHITA AREA WHERE IT WILL BEGIN TO STALL. SURFACE DEWPOINTS IN THE MIDDLE 50S ARE BEING PUSHED INTO SOUTHEAST KANSAS IN THE SHORT TERM AS A RESULT OF THE FRONTAL PASSAGE...BUT AS A LEE TROUGH AND RETURN SURFACE FLOW SET UP DURING THE DAY WEDNESDAY...LOW LEVEL MOISTURE WILL RAPIDLY RETURN TO NORTHWEST KANSAS. FORECAST SOUNDINGS HINT AT A STRATUS/STRATOCU DECK BY MIDDAY TOMORROW MOVING ACROSS OUR EASTERN COUNTIES. CANNOT RULE OUT SOME LIGHT SHOWERS AT THAT TIME GIVEN 700 MB WARM ADVECTION PATTERN. HAVE INCLUDED LOW POPS AND SHOWERS MAINLY FOR WEDNESDAY AFTERNOON IN THIS AREA. KEPT THUNDER OUT FOR THE TIME BEING GIVEN THE ANTICIPATED CLOUD COVER AND LACK OF GOOD INSTABILITY. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 200 PM MDT TUE MAR 27 2012 WEDNESDAY NIGHT-THURSDAY...LOW CLOUDS AND FOG EXPECTED WEDNESDAY NIGHT SLOWLY DECREASING IN COVERAGE THURSDAY MORNING. MAY HAVE A BRIEF PERIOD NORTH WINDS GUSTING 30 MPH ALONG AND WEST OF THE CO/KS BORDER DURING THE AFTERNOON AS A FRONT MOVES THROUGH. HIGH TEMPERATURES IN THE 70S. FRIDAY...DRY WITH HIGHS IN THE MID 70S TO AROUND 80. SATURDAY-MONDAY...ATTENTION TURNS TO DEVELOPING UPPER TROUGH WHICH BY 00Z SUNDAY SHOULD BE COMING ASHORE ALONG THE WEST COAST AND MOVING THROUGH THE FORECAST AREA BY 00Z MONDAY. BY 00Z TUESDAY THE SYSTEM IS EXPECTED TO LIFT NORTHEAST. SOUTHERLY WINDS WILL SLOWLY INCREASE THROUGH THE DAY SATURDAY AND MAY BECOME BREEZY ALONG AND WEST OF THE CO/KS BORDER. ON SUNDAY A COLD FRONT MOVES IN ASSOCIATED WITH THE UPPER TROUGH. WINDS WILL SHIFT TO THE NORTHWEST AND INCREASE IN SPEED WITH WINDY CONDITIONS EXPECTED. THESE GUSTY NORTHWEST WINDS WILL CONTINUE SUNDAY NIGHT AND MONDAY WITH GUSTS TO 45 MPH POSSIBLE. A WIND ADVISORY MAY BE NEEDED. HIGH TEMPERATURES SATURDAY IN THE 80S FALLING INTO THE LOW 70S WEST OF THE CO/KS BORDER SUNDAY...MID TO UPPER 70S EAST. ON MONDAY EXPECTED MID 50S TO LOW 60S WHICH IS RIGHT NEAR NORMAL FOR LATE MARCH. PRECIPITATION CHANCES WILL BE CONFINED TO SUNDAY AFTERNOON AND SUNDAY NIGHT WHERE SOME RAIN SHOWERS ARE POSSIBLE. TUESDAY...BROAD UPPER RIDGE REDEVELOPS AS SUNDAYS SYSTEM LIFTS TOWARD THE GREAT LAKES AND ANOTHER STORM MOVES TOWARD THE PACIFIC NORTHWEST. AFTERNOON HIGHS GENERALLY IN THE 60S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 451 PM MDT TUE MAR 27 2012 VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD. HIGH PRESSURE AT THE SURFACE WILL ALLOW FOR LIGHT AND VARIBALE WINDS TONIGHT...AND AS A HIGH PRESSURE CENTER MOVES OVER KMCK...WINDS SHOULD BEGIN TO TAKE ON MORE OF A SOUTHERLY COMPONENT AT KGLD DURING THE MORNING HOURS. PRESSURE WILL DEEPEN OVER EASTERN COLORADO DURING THE DAYTIME HOURS ON WEDNESDAY...CAUSING WINDS TO BECOME SOUTHERLY AT KMCK AND GUST TO NEAR 18 KNOTS DURING THE AFTERNOON. && .FIRE WEATHER... ISSUED AT 200 PM MDT TUE MAR 27 2012 THURSDAY AFTERNOON...THE COMBINATION OF RELATIVE HUMIDITY BELOW 20 PERCENT AND NORTH WINDS GUSTING TO 30 MPH MAY CREATE CRITICAL FIRE WEATHER CONDITIONS GENERALLY WEST OF A LINE FROM BENKELMAN NEBRASKA TO GOODLAND. SUNDAY AFTERNOON...RELATIVE HUMIDITY WILL BE BELOW 20 PERCENT. WEST TO SOUTHWEST WINDS OF 15 TO 20 MPH WITH HIGHER GUSTS MID TO LATE AFTERNOON WILL SHIFT TO THE NORTHWEST AND GUST AROUND 30 MPH LATE IN THE DAY TO CREATE CRITICAL FIRE WEATHER CONDITIONS...GENERALLY WEST OF A LINE FROM TRENTON NEBRASKA TO GOODLAND AND TRIBUNE KANSAS. MONDAY AFTERNOON AND TUESDAY AFTERNOON...CRITICAL FIRE WEATHER CONDITIONS EXPECTED ACROSS THE ENTIRE FORECAST AREA AS NORTHWEST WINDS GUSTING IN THE 35 TO 45 MPH RANGE COMBINE WITH AFTERNOON HUMIDITY BELOW 20 PERCENT. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...NONE. KS...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...DLF LONG TERM....007 AVIATION...CJS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
500 PM CDT MON MAR 26 2012 .UPDATE... ISSUED AT 455 PM CDT MON MAR 26 2012 HAVE TRIMMED POPS FOR THIS EVENING DUE TO LAPS/SPC MESOANALYSIS SHOWING SBCAPE AROUND 500 J/KG BUT CINH AROUND NEGATIVE 200 TO 400 J/KG. DEWPOINTS ARE MIXING OUT THIS AFTERNOON AND ARE ONLY IN THE LOWER 40S ACROSS WESTERN KANSAS. FOLLOWED THE LATEST HRRR FOR GUIDANCE. HAVE DOUBTS ANY ORGANIZED CONVECTION WILL FORM THIS EVENING AND THE INSTABILITY THAT IS CURRENTLY PRESENT WILL ALL GO TO MID LEVEL CLOUD FORMATION. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 215 PM CDT MON MAR 26 2012 THE MAIN FORECAST FOCUS WILL BE ON THE CHANCE FOR PRECIP DURING THE PERIOD. SHORT RANGE MODELS INDICATE THE UPPER LEVEL TROUGH LIFTING NORTHEAST ACROSS THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS TONIGHT BRINGING THE POSSIBILITY FOR SHOWERS AND THUNDERSTORMS ACROSS THE DAKOTAS SOUTHWARD INTO NEBRASKA, POTENTIALLY AS FAR SOUTH AS KANSAS. AS THE UPPER LEVEL WAVE BEGINS TO PUSH OUT OF THE NORTHERN ROCKIES THIS EVENING, THE SURFACE TROUGH IN EASTERN COLORADO AND AN ASSOCIATED SHARPENING DRYLINE IS EXPECTED TO PUSH SLOWLY EASTWARD INTO EXTREME WESTERN KANSAS INCREASING FORCING NEAR THE SURFACE. THIS WILL ALSO SUPPORT AN INCREASING LOW LEVEL SOUTHERLY FLOW INTO WESTERN KANSAS HELPING TO POOL SOME MOISTURE AHEAD OF THE ADVANCING TROUGH. HOWEVER, THE BEST UPPER LEVEL DYNAMICS ASSOCIATED WITH THE SYSTEM...INCLUDING A MODEST +70KT JET...WILL SKIRT JUST OFF TO OUR NORTHWEST. ADDITIONALLY, THE DEEPER LAYER MOISTURE WILL ALSO REMAIN JUST OFF TO OUR NORTH. ALTHOUGH THE NAM AND GFS MODEL SOUNDINGS POINT TO STEEPENING LAPSE RATES ACROSS WESTERN KANSAS, THERE IS A LACK OF INSTABILITY (LOW CAPE) DUE TO THE LACK OF MOISTURE IN THE LOWER LEVELS, NOT TO MENTION A POSSIBLE CAPPING ISSUE. STILL, CANNOT RULE OUT AN ISOLATED STORM OR TWO ASSOCIATED WITH THE DRYLINE AS IT TRACKS EAST ACROSS WESTERN KANSAS OVERNIGHT. SLIGHT POPS SEEM REASONABLE HERE. TEMPERATURES ARE EXPECTED TO REMAIN ABOVE NORMAL TONIGHT AS THE APPROACHING LEE SIDE TROUGH CONTINUES TO ENHANCE WARM AIR ADVECTION INTO WESTERN KANSAS WITHIN A LOW LEVEL SOUTHERLY FLOW. LOOK FOR LOWS MAINLY DOWN INTO THE 50S(F) AHEAD OF THE TROUGH WHERE SURFACE DEWPOINTS SHOULD REMAIN IN THE 40S(F) TO LOW 50S(F). A FEW 40S(F) ARE POSSIBLE ACROSS FAR WEST AND WEST CENTRAL KANSAS WHERE WINDS ARE EXPECTED TO GO NORTHERLY BEHIND A WEAK COLD FRONT EDGING INTO WESTERN KANSAS EARLY TUESDAY MORNING. FOR TUESDAY, A SMALL AREA OF SURFACE HIGH PRESSURE IS PROJECTED TO WORK EASTWARD INTO WESTERN KANSAS DURING THE DAY BRINGING SLIGHTLY COOLER AIR INTO THE REGION WITH H85 TEMPERATURES IN THE MID TEENS(C). SHOULD SEE HIGHS UP INTO THE 70S(F) FOR THE MOST PART WITH LOWER 80S(F) POSSIBLE ACROSS SOUTH CENTRAL KANSAS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 344 PM CDT MON MAR 26 2012 THE 12Z RUNS OF THE GFS/ECMWF/CANADIAN AND UKMET ARE ALL IN FAIRLY DECENT AGREEMENT WITH THE UPPER LEVEL FLOW PATTERN THROUGH DAY 5 BEFORE STARTING TO DIVERGE IN THEIR SOLUTIONS. AT THE BEGINNING OF THE LONG TERM PERIOD ON TUESDAY NIGHT...THE STRONG UPPER LEVEL SHORTWAVE TROUGH THAT IS CURRENTLY LIFTING OUT OF THE WESTERN STATES INTO THE NORTHERN PLAINS WILL HAVE MOVED INTO THE GREAT LAKES REGION WHILE A SHORTWAVE RIDGE MOVES EAST TOWARD THE NORTHERN AND CENTRAL PLAINS. THE MODELS SHOW A STALLED FRONTAL BOUNDARY OVER SOUTH CENTRAL KANSAS SOMEWHERE IN THE VICINITY OF STAFFORD TO MEDICINE LODGE AND COLDWATER. THE MODELS ARE ALL SHOWING A PRECIPITATION SIGNAL ALONG THE FRONT. WITH DEWPOINTS PROGGED TO BE IN THE LOW 60S AROUND MEDICINE LODGE, MODEL SOUNDINGS SHOW THE ATMOSPHERE NEARLY UNCAPPED BY LATE AFTERNOON WITH SOME MODERATE CAPE VALUES FORECAST. AN EIGHTY KNOT JET WILL BE MOVING EAST ACROSS SOUTH DAKOTA THROUGH THE EVENING AND OVERNIGHT HOURS WHICH COULD ALSO PROVIDE A LITTLE UPPER LEVEL SUPPORT FOR STORMS. WILL MAINTAIN THE SLIGHT CHANCE POPS FORECAST FOR SOUTH CENTRAL KANSAS. FARTHER NORTHWEST IT APPEARS THAT THE ATMOSPHERE SHOULD BE SUFFICIENTLY CAPPED TO PREVENT ANY THUNDERSTORM DEVELOPMENT. THE WEATHER SHOULD BE FAIRLY QUIET ON WEDNESDAY WITH THE SHORTWAVE RIDGE MOVING OVER THE CENTRAL HIGH PLAINS. BY WEDNESDAY NIGHT LOW LEVEL SOUTHERLY FLOW INCREASES ESPECIALLY INTO SOUTH CENTRAL KANSAS. WITH LOW LEVEL MOISTURE INCREASING INTO THE AREA WE COULD SEE THUNDERSTORMS DEVELOPING AGAIN WITH THE BEST CHANCES AROUND HIGHWAY 281 AND EAST. THERE IS SOME UNCERTAINTY AS TO THE POSITION AND STRENGTH OF THE FRONTAL BOUNDARY FOR NOW WILL KEEP THE POPS IN THE PRATT-MEDICINE LODGE-COLDWATER AREAS. THE MODELS SHOW A WEAK SHORTWAVE TROUGH APPROACHING THE CENTRAL CONUS ON THURSDAY. THE GFS SHOWS A WEAK COOL FRONT PUSHING ACROSS WESTERN KANSAS. WILL CONTINUE THE CHANCE POPS THAT ARE CURRENTLY IN THE FORECAST FOR THURSDAY NIGHT. TOWARD DAY 7 THE MODELS DIFFER SOMEWHAT WITH THE STRENGTH AND TRACK OF ANOTHER STRONG SHORTWAVE MOVING IN FROM THE PACIFIC. THE MODELS HAVE STRUGGLED WITH THIS FROM RUN TO RUN SO CONFIDENCE IN ANY ONE SOLUTION IS PRETTY LOW. THE GFS MODEL SHOWS A FAIRLY STRONG COLD FRONT PUSH THROUGH WESTERN KANSAS LATE IN THE WEEKEND WITH SOME POTENTIAL FREEZING TEMPERATURES. WILL HAVE TO KEEP AN EYE ON THIS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1200 PM CDT MON MAR 26 2012 VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGH EARLY TUESDAY MORNING. AS FOR WINDS, A STRONG LEE SIDE TROUGH OF LOW PRESSURE WILL EDGE SLOWLY EASTWARD INTO EXTREME WESTERN KANSAS TONIGHT. AS A RESULT, SOUTHERLY WINDS OF 25 TO 35KT WILL CONTINUE INTO EARLY THIS EVENING THEN GRADUALLY SUBSIDE WEST TO EAST OVERNIGHT AS THE TROUGH PUSHES THROUGH. && .PRELIMINARY POINT TEMPS/POPS... DDC 50 77 49 81 / 20 0 10 10 GCK 46 75 45 80 / 20 0 10 10 EHA 45 75 43 80 / 10 0 0 0 LBL 50 77 45 81 / 20 0 0 10 HYS 50 75 46 80 / 10 0 10 10 P28 57 80 56 82 / 0 10 20 10 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR KSZ030- 031-043>046-061>066-074>080-084>089. && $$ UPDATE...SUGDEN SHORT TERM...JJOHNSON LONG TERM....GERARD AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1135 AM MDT MON MAR 26 2012 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 143 AM MDT MON MAR 26 2012 03Z WATER IMAGERY INDICATED LARGE UPPER LEVEL RIDGE IN PLACE ACROSS THE PLAINS WITH SHORT WAVE TROUGH/CLOSED LOW CIRCULATION ENTERING SOUTHERN CALIFORNIA. AT THE SFC...AREA OF LOW PRESSURE WAS IN PLACE ACROSS SOUTHEAST COLORADO IN A SIMILAR POSITION FROM 24 HOURS AGO...WITH LIGHT EASTERLY FLOW ACROSS NORTHERN HALF OF THE AREA. 00Z RAOBS INDICATED A SHARP CHANGE IN MOISTURE CONTENT FROM WEST TO EAST ACROSS THE PLAINS WITH FAIRLY LARGE INCREASES IN MOISTURE BELOW H75 NOTED AT KDDC AND KLBF FROM 24 HOURS AGO...AS EVIDENCED BY +0.3 CHANGE IN PRECIPITABLE WATER OVER THAT TIME. ASIDE FROM OVERNIGHT FOG AND VERY SMALL THUNDERSTORM CHANCES...MAIN FORECAST CONCERNS WILL BE WINDS/FIRE WX AND THUNDERSTORM CHANCES TODAY AND TONIGHT. TODAY-TONIGHT...ALTHOUGH SOME ELEVATED INSTABILITY WILL LINGER AROUND DURING THE MORNING HOURS WITH LATEST RUNS OF HRRR TRYING TO BREAK OUT SOME WEAK CONVECTION AROUND 12Z...ISENTROPIC FIELDS SUGGEST BULK OF FORCING ALONG NOSE OF LLJ WILL BE WELL TO THE NORTH AND EAST OF THE CWA AND WITH CONDENSATION DEFICITS IN EXCESS OF 130 MB...SEEMS DOUBTFUL ANY MORNING INSTABILITY WOULD BE REALIZED AND THINK BULK OF MORNING WX CONCERNS WILL CENTER AROUND ANY LINGERING FOG AROUND SUNRISE. WITH WINDS SHIFTING AROUND TO THE SOUTHWEST AND INCREASING DO NOT THINK FOG WILL BE AS WIDESPREAD OR DENSE LIKE YESTERDAY...BUT WILL MONITOR OBSERVATIONS CLOSELY AND ADJUST AS TRENDS DICTATE. BEST...ALBEIT SMALL...CHANCE FOR PRECIP WILL BE BETWEEN 21 AND 03Z AS CONVERGENCE ALONG DRYLINE REALLY BEGINS TO SHARPEN AND LOW LEVEL FRONTOGENESIS INCREASES. AREA WILL STILL BE PRETTY FAR REMOVED FROM LARGE SCALE FORCING FOR ASCENT AS UPPER TROUGH PASSES ACROSS WYOMING AND WITH STRONG CAP/CINH IN PLACE HAVE DOUBTS ABOUT CONVECTIVE INITIATION AND IF STORMS WOULD ACTUALLY SURVIVE FOR VERY LONG AS THEY MOVED AWAY FROM SFC FORCING. STILL FEEL SMALL POPS WARRANTED AND GIVEN SHEAR/INSTABILITY PROFILES THERE IS A SMALL CHANCE FOR AN ORGANIZED STORM OR TWO AS THINGS INITIATE NEAR THE KS/CO BORDER AND GRADUALLY SHIFT EAST IN THE EVENING. WITH THE RATHER SMALL PROBABILITIES FOR THUNDERSTORMS...WINDS AND FIRE WX WILL CONTINUE TO BE THE MAIN CONCERN FOR THE PERIOD AS WINDS WILL INCREASE RAPIDLY DURING THE AFTERNOON IN RESPONSE TO STRENGTHENING LOW ACROSS THE NEBRASKA PANHANDLE. WINDS SHOULD PRETTY EASILY MEET ADVISORY CONDITIONS ACROSS THE ENTIRE AREA...BUT HAVE A FEW CONCERNS THAT HIGHER GUSTS APPROACHING WARNING CRITERIA MAY OCCUR WITH THE MUCH DEEPER MIXING EXPECTED TO THE WEST OF DRYLINE. OPERATIONAL GUIDANCE NOT REALLY GIVING A SOLID CONSENSUS IN THIS REGARD AND WITH MIXED LAYER DATA GENERALLY TOPPING AT AROUND 48 KTS AND A WEAKER SFC LOW THAN LAST WEEK...THINK CONFIDENCE TOO LOW TO UPGRADE ADVISORY TO WARNING AT THIS POINT. FOR FIRE WEATHER CONDITIONS...THINK DRY LINE WILL HUG KS/CO BORDER FOR MUCH OF THE DAY AS STRONG PRESSURE FALLS OCCUR TO THE NORTHEAST. HOWEVER AS LOW BEGINS TO LIFT INTO THE NEBRASKA PANHANDLE...EXPECT DRYLINE TO START ADVANCING EASTWARD. IT WILL BE MARGINAL FROM A DURATION ASPECT...BUT FEEL UPGRADING FIRE WEATHER WATCH TO WARNING IS APPROPRIATE. TUESDAY...FRONTAL ZONE WILL STALL ACROSS SOUTHERN KANSAS DURING THE MORNING HOURS AS COOLER AIR SETTLES OVER THE AREA WITH ADVANCING SFC RIDGE. WITH A MORE STABLE AIRMASS SETTLING OVER THE AREA AND SHORT WAVE RIDGING STARTING TO DEVELOP...EXPECT DRY CONDITIONS AND GENERALLY CLEAR SKIES. ONLY SIG WEATHER CONCERN WILL BE MAGNITUDE OF DRY AIR THAT WILL BE ADVECTED INTO AREA BEHIND FRONT. ALTHOUGH AFTERNOON HUMIDITIES WILL FALL TO AROUND 15 PERCENT...POSITION OF SFC HIGH WILL LIKELY BRING LIGHT/VARIABLE WINDS TO MUCH OF THE AREA MITIGATING THE FIRE WX THREAT. COULD POSSIBLY SEE STRONGER WINDS ACROSS NEBRASKA COUNTIES...BUT THINK WITH CURRENT FIRE HIGHLIGHTS AND OVERALL LOW CONFIDENCE IN STRONGER WINDS DO NOT FEEL WATCH WARRANTED AT THIS TIME. TUESDAY NIGHT-WEDNESDAY NIGHT...SLOWLY RETREATING FRONTAL ZONE WILL LIKELY BE MAIN CONCERN FOR THE PERIOD AS NOT ONLY WILL THIS FEATURE PROVIDE A POTENTIAL FOCUS FOR THUNDERSTORM DEVELOPMENT...IT WILL ALSO BRING MUCH MORE HUMID AIR BACK TO THE CWA. GIVEN CWA WILL GENERALLY BE UNDER A FAIRLY WEAK SHORT WAVE RIDGE FOR MOST OF THE PERIOD...HAVE DOUBTS THAT FRONT WILL MAKE A RAPID NORTHERLY SURGE AND PREFER THE MORE SOUTHERLY SOLUTION GIVEN BY NAM AND LATEST ENSEMBLE MEANS. IF THERE IS A CHANCE FOR PRECIPITATION THIS PERIOD...THINK MOST LIKELY PERIOD WILL BE OVERNIGHT WEDNESDAY AS LLJ INCREASES THROUGH 06Z IN RESPONSE TO SHORT WAVE TROUGH MOVING ACROSS NORTHERN ROCKIES. NOT ONLY WILL THIS BRING A STRONG SURGE OF MOISTURE/INSTABILITY INTO AREA...BUT ISENTROPIC SURFACES SUGGEST FORCING WILL BE FOCUSED ACROSS EASTERN CWA DURING THE EVENING/OVERNIGHT HOURS. STILL A LOT OF CONCERNS ABOUT WHETHER OR NOT PARCELS WILL SATURATE AND INSTABILITY BE REALIZED...BUT THINK A SMALL THREAT FOR STORMS IS WARRANTED. IN ADDITION TO PRECIP POTENTIAL...INCREASING LOW LEVEL MOISTURE BOTH NIGHTS WILL LIKELY PROVIDE A FAVORABLE ENVIRONMENT FOR FOG FORMATION. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 1254 AM MDT MON MAR 26 2012 ZONAL FLOW WILL BE IN PLACE ACROSS THE CONUS TO START THIS PERIOD. WEAK SHORTWAVE TROUGHS WILL BE MOVING ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS BOTH THURSDAY AND FRIDAY. APPEARS THERE WILL BE AT LEAST SOME MOISTURE AVAILABLE AND COUPLED WITH WEAK INSTABILITY WILL CARRY SLIGHT TO LOW CHANCE POPS FOR AFTERNOON/EVENING THUNDERSTORMS BOTH DAYS. UPPER RIDGE WILL BUILD ACROSS THE PLAINS FOR THE REMAINDER OF THE PERIOD AHEAD OF STRONG SYSTEM DIGGING INTO THE FOUR CORNERS. MODEL SOLUTIONS DIVERGE ON HOW TO HANDLE THAT SYSTEM VERY LATE IN THE PERIOD...SO WILL NOT CARRY ANY MENTION OF PRECIPITATION ATTM. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE ENTIRE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1135 AM MDT MON MAR 26 2012 STRONG SOUTHERLY WINDS WILL PREVAIL AT THE TERMINALS THIS AFTERNOON DUE TO A LOW PRESSURE CENTER TO THE NORTH OF THE TERMINALS. THERE WILL BE A SLIGHT POSSIBILITY FOR THUNDERSTORMS EAST OF A DRYLINE THIS AFTERNOON AND INTO THE EARLY EVENING. AS A COLD FRONT MOVES THROUGH THE TERMINALS THIS EVENING...WINDS WILL SHIFT TO THE WEST-NORTHWEST...AND WHILE GUSTS ARE NOT EXPECTED TO BE AS STRONG THIS EVENING AS THEY WERE THIS AFTERNOON...WIND GUSTS CAN STILL BE EXPECTED UNTIL THE PRESSURE GRADIENT RELAXES DURING THE EARLY MORNING HOURS. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...ALLOWING LIGHT WINDS AND CLEAR SKIES ON TUESDAY MORNING AT KGLD...BUT WIND GUSTS SHOULD RETURN TO KMCK GIVEN ITS PROXIMITY TO THE HIGH PRESSURE CENTER. && .FIRE WEATHER... ISSUED AT 143 AM MDT MON MAR 26 2012 CRITICAL TO EXTREMELY CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TODAY...MAINLY ALONG AND WEST OF THE KANSAS AND COLORADO STATE LINE AS A DRYLINE SLOWLY ADVANCES TO THE EAST TODAY. STRONG SOUTHERLY WINDS OF 25 TO 35 MPH WITH GUSTS TO AROUND 55 MPH WILL COMBINE WITH HUMIDITIES AROUND 10 PERCENT DURING THE AFTERNOON AND EARLY EVENING HOURS. A COLD FRONT WILL BEGIN TO MOVE ACROSS THE AREA TONIGHT...BRINGING A SUDDEN SHIFT IN THE WINDS AND A BRIEF PERIOD OF STRONG NORTHWESTERLY WINDS. A VERY DRY AIR MASS WILL SETTLE OVER THE AREA ON TUESDAY BRINGING HUMIDITIES DOWN TO AROUND 15 PERCENT DURING THE AFTERNOON. WHILE WINDS WILL BE LIGHT AND VARIABLE ACROSS MUCH OF THE AREA...THERE IS POTENTIAL FOR STRONGER WINDS AND CRITICAL FIRE WEATHER CONDITIONS ACROSS SOUTHWEST NEBRASKA. IF WINDS DO OCCUR...WILL LIKELY BE A MUCH SMALLER MAGNITUDE OF EVENT THAN TODAY AND CHOSE TO NOT ISSUE A FIRE WEATHER WATCH TO AVOID CONFUSION ABOUT TODAYS WARNING. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ252>254. WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ090>092. KS...RED FLAG WARNING UNTIL 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001-013-027-041. WIND ADVISORY UNTIL 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001>004-013>016-027>029-041-042. NE...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR NEZ079. WIND ADVISORY UNTIL 9 PM MDT /10 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ SHORT TERM...JRM LONG TERM....024 AVIATION...CJS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
530 AM MDT MON MAR 26 2012 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 143 AM MDT MON MAR 26 2012 03Z WATER IMAGERY INDICATED LARGE UPPER LEVEL RIDGE IN PLACE ACROSS THE PLAINS WITH SHORT WAVE TROUGH/CLOSED LOW CIRCULATION ENTERING SOUTHERN CALIFORNIA. AT THE SFC...AREA OF LOW PRESSURE WAS IN PLACE ACROSS SOUTHEAST COLORADO IN A SIMILAR POSITION FROM 24 HOURS AGO...WITH LIGHT EASTERLY FLOW ACROSS NORTHERN HALF OF THE AREA. 00Z RAOBS INDICATED A SHARP CHANGE IN MOISTURE CONTENT FROM WEST TO EAST ACROSS THE PLAINS WITH FAIRLY LARGE INCREASES IN MOISTURE BELOW H75 NOTED AT KDDC AND KLBF FROM 24 HOURS AGO...AS EVIDENCED BY +0.3 CHANGE IN PRECIPITABLE WATER OVER THAT TIME. ASIDE FROM OVERNIGHT FOG AND VERY SMALL THUNDERSTORM CHANCES...MAIN FORECAST CONCERNS WILL BE WINDS/FIRE WX AND THUNDERSTORM CHANCES TODAY AND TONIGHT. TODAY-TONIGHT...ALTHOUGH SOME ELEVATED INSTABILITY WILL LINGER AROUND DURING THE MORNING HOURS WITH LATEST RUNS OF HRRR TRYING TO BREAK OUT SOME WEAK CONVECTION AROUND 12Z...ISENTROPIC FIELDS SUGGEST BULK OF FORCING ALONG NOSE OF LLJ WILL BE WELL TO THE NORTH AND EAST OF THE CWA AND WITH CONDENSATION DEFICITS IN EXCESS OF 130 MB...SEEMS DOUBTFUL ANY MORNING INSTABILITY WOULD BE REALIZED AND THINK BULK OF MORNING WX CONCERNS WILL CENTER AROUND ANY LINGERING FOG AROUND SUNRISE. WITH WINDS SHIFTING AROUND TO THE SOUTHWEST AND INCREASING DO NOT THINK FOG WILL BE AS WIDESPREAD OR DENSE LIKE YESTERDAY...BUT WILL MONITOR OBSERVATIONS CLOSELY AND ADJUST AS TRENDS DICTATE. BEST...ALBEIT SMALL...CHANCE FOR PRECIP WILL BE BETWEEN 21 AND 03Z AS CONVERGENCE ALONG DRYLINE REALLY BEGINS TO SHARPEN AND LOW LEVEL FRONTOGENESIS INCREASES. AREA WILL STILL BE PRETTY FAR REMOVED FROM LARGE SCALE FORCING FOR ASCENT AS UPPER TROUGH PASSES ACROSS WYOMING AND WITH STRONG CAP/CINH IN PLACE HAVE DOUBTS ABOUT CONVECTIVE INITIATION AND IF STORMS WOULD ACTUALLY SURVIVE FOR VERY LONG AS THEY MOVED AWAY FROM SFC FORCING. STILL FEEL SMALL POPS WARRANTED AND GIVEN SHEAR/INSTABILITY PROFILES THERE IS A SMALL CHANCE FOR AN ORGANIZED STORM OR TWO AS THINGS INITIATE NEAR THE KS/CO BORDER AND GRADUALLY SHIFT EAST IN THE EVENING. WITH THE RATHER SMALL PROBABILITIES FOR THUNDERSTORMS...WINDS AND FIRE WX WILL CONTINUE TO BE THE MAIN CONCERN FOR THE PERIOD AS WINDS WILL INCREASE RAPIDLY DURING THE AFTERNOON IN RESPONSE TO STRENGTHENING LOW ACROSS THE NEBRASKA PANHANDLE. WINDS SHOULD PRETTY EASILY MEET ADVISORY CONDITIONS ACROSS THE ENTIRE AREA...BUT HAVE A FEW CONCERNS THAT HIGHER GUSTS APPROACHING WARNING CRITERIA MAY OCCUR WITH THE MUCH DEEPER MIXING EXPECTED TO THE WEST OF DRYLINE. OPERATIONAL GUIDANCE NOT REALLY GIVING A SOLID CONSENSUS IN THIS REGARD AND WITH MIXED LAYER DATA GENERALLY TOPPING AT AROUND 48 KTS AND A WEAKER SFC LOW THAN LAST WEEK...THINK CONFIDENCE TOO LOW TO UPGRADE ADVISORY TO WARNING AT THIS POINT. FOR FIRE WEATHER CONDITIONS...THINK DRY LINE WILL HUG KS/CO BORDER FOR MUCH OF THE DAY AS STRONG PRESSURE FALLS OCCUR TO THE NORTHEAST. HOWEVER AS LOW BEGINS TO LIFT INTO THE NEBRASKA PANHANDLE...EXPECT DRYLINE TO START ADVANCING EASTWARD. IT WILL BE MARGINAL FROM A DURATION ASPECT...BUT FEEL UPGRADING FIRE WEATHER WATCH TO WARNING IS APPROPRIATE. TUESDAY...FRONTAL ZONE WILL STALL ACROSS SOUTHERN KANSAS DURING THE MORNING HOURS AS COOLER AIR SETTLES OVER THE AREA WITH ADVANCING SFC RIDGE. WITH A MORE STABLE AIRMASS SETTLING OVER THE AREA AND SHORT WAVE RIDGING STARTING TO DEVELOP...EXPECT DRY CONDITIONS AND GENERALLY CLEAR SKIES. ONLY SIG WEATHER CONCERN WILL BE MAGNITUDE OF DRY AIR THAT WILL BE ADVECTED INTO AREA BEHIND FRONT. ALTHOUGH AFTERNOON HUMIDITIES WILL FALL TO AROUND 15 PERCENT...POSITION OF SFC HIGH WILL LIKELY BRING LIGHT/VARIABLE WINDS TO MUCH OF THE AREA MITIGATING THE FIRE WX THREAT. COULD POSSIBLY SEE STRONGER WINDS ACROSS NEBRASKA COUNTIES...BUT THINK WITH CURRENT FIRE HIGHLIGHTS AND OVERALL LOW CONFIDENCE IN STRONGER WINDS DO NOT FEEL WATCH WARRANTED AT THIS TIME. TUESDAY NIGHT-WEDNESDAY NIGHT...SLOWLY RETREATING FRONTAL ZONE WILL LIKELY BE MAIN CONCERN FOR THE PERIOD AS NOT ONLY WILL THIS FEATURE PROVIDE A POTENTIAL FOCUS FOR THUNDERSTORM DEVELOPMENT...IT WILL ALSO BRING MUCH MORE HUMID AIR BACK TO THE CWA. GIVEN CWA WILL GENERALLY BE UNDER A FAIRLY WEAK SHORT WAVE RIDGE FOR MOST OF THE PERIOD...HAVE DOUBTS THAT FRONT WILL MAKE A RAPID NORTHERLY SURGE AND PREFER THE MORE SOUTHERLY SOLUTION GIVEN BY NAM AND LATEST ENSEMBLE MEANS. IF THERE IS A CHANCE FOR PRECIPITATION THIS PERIOD...THINK MOST LIKELY PERIOD WILL BE OVERNIGHT WEDNESDAY AS LLJ INCREASES THROUGH 06Z IN RESPONSE TO SHORT WAVE TROUGH MOVING ACROSS NORTHERN ROCKIES. NOT ONLY WILL THIS BRING A STRONG SURGE OF MOISTURE/INSTABILITY INTO AREA...BUT ISENTROPIC SURFACES SUGGEST FORCING WILL BE FOCUSED ACROSS EASTERN CWA DURING THE EVENING/OVERNIGHT HOURS. STILL A LOT OF CONCERNS ABOUT WHETHER OR NOT PARCELS WILL SATURATE AND INSTABILITY BE REALIZED...BUT THINK A SMALL THREAT FOR STORMS IS WARRANTED. IN ADDITION TO PRECIP POTENTIAL...INCREASING LOW LEVEL MOISTURE BOTH NIGHTS WILL LIKELY PROVIDE A FAVORABLE ENVIRONMENT FOR FOG FORMATION. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 1254 AM MDT MON MAR 26 2012 ZONAL FLOW WILL BE IN PLACE ACROSS THE CONUS TO START THIS PERIOD. WEAK SHORTWAVE TROUGHS WILL BE MOVING ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS BOTH THURSDAY AND FRIDAY. APPEARS THERE WILL BE AT LEAST SOME MOISTURE AVAILABLE AND COUPLED WITH WEAK INSTABILITY WILL CARRY SLIGHT TO LOW CHANCE POPS FOR AFTERNOON/EVENING THUNDERSTORMS BOTH DAYS. UPPER RIDGE WILL BUILD ACROSS THE PLAINS FOR THE REMAINDER OF THE PERIOD AHEAD OF STRONG SYSTEM DIGGING INTO THE FOUR CORNERS. MODEL SOLUTIONS DIVERGE ON HOW TO HANDLE THAT SYSTEM VERY LATE IN THE PERIOD...SO WILL NOT CARRY ANY MENTION OF PRECIPITATION ATTM. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE ENTIRE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 523 AM MDT MON MAR 26 2012 PATCHY FOG AND SOME LINGERING LLWS WILL CONTINUE AROUND MCK THROUGH 13Z AS WEAK FRONTAL ZONE IS DRAPED ACROSS THE AREA WILL QUICKLY LIFT TO THE NORTH BRINGING PREVAILING VFR CONDITIONS AND A PROFILE LESS FAVORABLE FOR LLWS. OTHERWISE MAIN CONCERN FOR PERIOD WILL BE HOW FAST AND HOW STRONG WINDS WILL BE...MAINLY BTNW 20-01Z AT BOTH TERMINALS. WILL LIKELY SEE GUSTS GET TO AROUND 44KTS AT BOTH LOCATIONS...WITH WINDS BRIEFLY WEAKENING IN THE EVENING BEFORE STRONG COLD FRONT/WIND SHIFT COMES THROUGH AFTER 04Z. COULD STILL SEE SOME BLOWING DUST CAUSING VISBY RESTRICTIONS...ESPECIALLY AS DRYLINE MOVES THROUGH GLD BUT WITH RECENT WIDESPREAD RAINFALL DO NOT THINK PROBABILITIES ARE HIGH ENOUGH TO INCLUDE. EXPECTED COVERAGE FOR THUNDERSTORMS TODAY WILL BE VERY LOW AND DO NOT PLAN ON INCLUDING EVEN A VCTS AT THIS POINT. && .FIRE WEATHER... ISSUED AT 143 AM MDT MON MAR 26 2012 CRITICAL TO EXTREMELY CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TODAY...MAINLY ALONG AND WEST OF THE KANSAS AND COLORADO STATE LINE AS A DRYLINE SLOWLY ADVANCES TO THE EAST TODAY. STRONG SOUTHERLY WINDS OF 25 TO 35 MPH WITH GUSTS TO AROUND 55 MPH WILL COMBINE WITH HUMIDITIES AROUND 10 PERCENT DURING THE AFTERNOON AND EARLY EVENING HOURS. A COLD FRONT WILL BEGIN TO MOVE ACROSS THE AREA TONIGHT...BRINGING A SUDDEN SHIFT IN THE WINDS AND A BRIEF PERIOD OF STRONG NORTHWESTERLY WINDS. A VERY DRY AIR MASS WILL SETTLE OVER THE AREA ON TUESDAY BRINGING HUMIDITIES DOWN TO AROUND 15 PERCENT DURING THE AFTERNOON. WHILE WINDS WILL BE LIGHT AND VARIABLE ACROSS MUCH OF THE AREA...THERE IS POTENTIAL FOR STRONGER WINDS AND CRITICAL FIRE WEATHER CONDITIONS ACROSS SOUTHWEST NEBRASKA. IF WINDS DO OCCUR...WILL LIKELY BE A MUCH SMALLER MAGNITUDE OF EVENT THAN TODAY AND CHOSE TO NOT ISSUE A FIRE WEATHER WATCH TO AVOID CONFUSION ABOUT TODAYS WARNING. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ252>254. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ090>092. KS...RED FLAG WARNING FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001-013-027-041. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001>004-013>016-027>029-041-042. NE...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ079. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ SHORT TERM...JRM LONG TERM....024 AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
150 AM MDT MON MAR 26 2012 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 143 AM MDT MON MAR 26 2012 03Z WATER IMAGERY INDICATED LARGE UPPER LEVEL RIDGE IN PLACE ACROSS THE PLAINS WITH SHORT WAVE TROUGH/CLOSED LOW CIRCULATION ENTERING SOUTHERN CALIFORNIA. AT THE SFC...AREA OF LOW PRESSURE WAS IN PLACE ACROSS SOUTHEAST COLORADO IN A SIMILAR POSITION FROM 24 HOURS AGO...WITH LIGHT EASTERLY FLOW ACROSS NORTHERN HALF OF THE AREA. 00Z RAOBS INDICATED A SHARP CHANGE IN MOISTURE CONTENT FROM WEST TO EAST ACROSS THE PLAINS WITH FAIRLY LARGE INCREASES IN MOISTURE BELOW H75 NOTED AT KDDC AND KLBF FROM 24 HOURS AGO...AS EVIDENCED BY +0.3 CHANGE IN PRECIPITABLE WATER OVER THAT TIME. ASIDE FROM OVERNIGHT FOG AND VERY SMALL THUNDERSTORM CHANCES...MAIN FORECAST CONCERNS WILL BE WINDS/FIRE WX AND THUNDERSTORM CHANCES TODAY AND TONIGHT. TODAY-TONIGHT...ALTHOUGH SOME ELEVATED INSTABILITY WILL LINGER AROUND DURING THE MORNING HOURS WITH LATEST RUNS OF HRRR TRYING TO BREAK OUT SOME WEAK CONVECTION AROUND 12Z...ISENTROPIC FIELDS SUGGEST BULK OF FORCING ALONG NOSE OF LLJ WILL BE WELL TO THE NORTH AND EAST OF THE CWA AND WITH CONDENSATION DEFICITS IN EXCESS OF 130 MB...SEEMS DOUBTFUL ANY MORNING INSTABILITY WOULD BE REALIZED AND THINK BULK OF MORNING WX CONCERNS WILL CENTER AROUND ANY LINGERING FOG AROUND SUNRISE. WITH WINDS SHIFTING AROUND TO THE SOUTHWEST AND INCREASING DO NOT THINK FOG WILL BE AS WIDESPREAD OR DENSE LIKE YESTERDAY...BUT WILL MONITOR OBSERVATIONS CLOSELY AND ADJUST AS TRENDS DICTATE. BEST...ALBEIT SMALL...CHANCE FOR PRECIP WILL BE BETWEEN 21 AND 03Z AS CONVERGENCE ALONG DRYLINE REALLY BEGINS TO SHARPEN AND LOW LEVEL FRONTOGENESIS INCREASES. AREA WILL STILL BE PRETTY FAR REMOVED FROM LARGE SCALE FORCING FOR ASCENT AS UPPER TROUGH PASSES ACROSS WYOMING AND WITH STRONG CAP/CINH IN PLACE HAVE DOUBTS ABOUT CONVECTIVE INITIATION AND IF STORMS WOULD ACTUALLY SURVIVE FOR VERY LONG AS THEY MOVED AWAY FROM SFC FORCING. STILL FEEL SMALL POPS WARRANTED AND GIVEN SHEAR/INSTABILITY PROFILES THERE IS A SMALL CHANCE FOR AN ORGANIZED STORM OR TWO AS THINGS INITIATE NEAR THE KS/CO BORDER AND GRADUALLY SHIFT EAST IN THE EVENING. WITH THE RATHER SMALL PROBABILITIES FOR THUNDERSTORMS...WINDS AND FIRE WX WILL CONTINUE TO BE THE MAIN CONCERN FOR THE PERIOD AS WINDS WILL INCREASE RAPIDLY DURING THE AFTERNOON IN RESPONSE TO STRENGTHENING LOW ACROSS THE NEBRASKA PANHANDLE. WINDS SHOULD PRETTY EASILY MEET ADVISORY CONDITIONS ACROSS THE ENTIRE AREA...BUT HAVE A FEW CONCERNS THAT HIGHER GUSTS APPROACHING WARNING CRITERIA MAY OCCUR WITH THE MUCH DEEPER MIXING EXPECTED TO THE WEST OF DRYLINE. OPERATIONAL GUIDANCE NOT REALLY GIVING A SOLID CONSENSUS IN THIS REGARD AND WITH MIXED LAYER DATA GENERALLY TOPPING AT AROUND 48 KTS AND A WEAKER SFC LOW THAN LAST WEEK...THINK CONFIDENCE TOO LOW TO UPGRADE ADVISORY TO WARNING AT THIS POINT. FOR FIRE WEATHER CONDITIONS...THINK DRY LINE WILL HUG KS/CO BORDER FOR MUCH OF THE DAY AS STRONG PRESSURE FALLS OCCUR TO THE NORTHEAST. HOWEVER AS LOW BEGINS TO LIFT INTO THE NEBRASKA PANHANDLE...EXPECT DRYLINE TO START ADVANCING EASTWARD. IT WILL BE MARGINAL FROM A DURATION ASPECT...BUT FEEL UPGRADING FIRE WEATHER WATCH TO WARNING IS APPROPRIATE. TUESDAY...FRONTAL ZONE WILL STALL ACROSS SOUTHERN KANSAS DURING THE MORNING HOURS AS COOLER AIR SETTLES OVER THE AREA WITH ADVANCING SFC RIDGE. WITH A MORE STABLE AIRMASS SETTLING OVER THE AREA AND SHORT WAVE RIDGING STARTING TO DEVELOP...EXPECT DRY CONDITIONS AND GENERALLY CLEAR SKIES. ONLY SIG WEATHER CONCERN WILL BE MAGNITUDE OF DRY AIR THAT WILL BE ADVECTED INTO AREA BEHIND FRONT. ALTHOUGH AFTERNOON HUMIDITIES WILL FALL TO AROUND 15 PERCENT...POSITION OF SFC HIGH WILL LIKELY BRING LIGHT/VARIABLE WINDS TO MUCH OF THE AREA MITIGATING THE FIRE WX THREAT. COULD POSSIBLY SEE STRONGER WINDS ACROSS NEBRASKA COUNTIES...BUT THINK WITH CURRENT FIRE HIGHLIGHTS AND OVERALL LOW CONFIDENCE IN STRONGER WINDS DO NOT FEEL WATCH WARRANTED AT THIS TIME. TUESDAY NIGHT-WEDNESDAY NIGHT...SLOWLY RETREATING FRONTAL ZONE WILL LIKELY BE MAIN CONCERN FOR THE PERIOD AS NOT ONLY WILL THIS FEATURE PROVIDE A POTENTIAL FOCUS FOR THUNDERSTORM DEVELOPMENT...IT WILL ALSO BRING MUCH MORE HUMID AIR BACK TO THE CWA. GIVEN CWA WILL GENERALLY BE UNDER A FAIRLY WEAK SHORT WAVE RIDGE FOR MOST OF THE PERIOD...HAVE DOUBTS THAT FRONT WILL MAKE A RAPID NORTHERLY SURGE AND PREFER THE MORE SOUTHERLY SOLUTION GIVEN BY NAM AND LATEST ENSEMBLE MEANS. IF THERE IS A CHANCE FOR PRECIPITATION THIS PERIOD...THINK MOST LIKELY PERIOD WILL BE OVERNIGHT WEDNESDAY AS LLJ INCREASES THROUGH 06Z IN RESPONSE TO SHORT WAVE TROUGH MOVING ACROSS NORTHERN ROCKIES. NOT ONLY WILL THIS BRING A STRONG SURGE OF MOISTURE/INSTABILITY INTO AREA...BUT ISENTROPIC SURFACES SUGGEST FORCING WILL BE FOCUSED ACROSS EASTERN CWA DURING THE EVENING/OVERNIGHT HOURS. STILL A LOT OF CONCERNS ABOUT WHETHER OR NOT PARCELS WILL SATURATE AND INSTABILITY BE REALIZED...BUT THINK A SMALL THREAT FOR STORMS IS WARRANTED. IN ADDITION TO PRECIP POTENTIAL...INCREASING LOW LEVEL MOISTURE BOTH NIGHTS WILL LIKELY PROVIDE A FAVORABLE ENVIRONMENT FOR FOG FORMATION. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 1254 AM MDT MON MAR 26 2012 ZONAL FLOW WILL BE IN PLACE ACROSS THE CONUS TO START THIS PERIOD. WEAK SHORTWAVE TROUGHS WILL BE MOVING ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS BOTH THURSDAY AND FRIDAY. APPEARS THERE WILL BE AT LEAST SOME MOISTURE AVAILABLE AND COUPLED WITH WEAK INSTABILITY WILL CARRY SLIGHT TO LOW CHANCE POPS FOR AFTERNOON/EVENING THUNDERSTORMS BOTH DAYS. UPPER RIDGE WILL BUILD ACROSS THE PLAINS FOR THE REMAINDER OF THE PERIOD AHEAD OF STRONG SYSTEM DIGGING INTO THE FOUR CORNERS. MODEL SOLUTIONS DIVERGE ON HOW TO HANDLE THAT SYSTEM VERY LATE IN THE PERIOD...SO WILL NOT CARRY ANY MENTION OF PRECIPITATION ATTM. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE ENTIRE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1145 PM MDT SUN MAR 25 2012 LOT OF CHANGES/THINGS TO CONSIDER FOR THIS SET OF TAFS. BEFORE THE STRONGER WINDS DEVELOP...IFR/MVFR CEILINGS/VISIBILITIES EXPECTED AT KMCK. BY 14Z VFR CONDITIONS ARE EXPECTED TO RETURN TO KMCK. SOUTHERLY WINDS ARE THEN EXPECTED TO INCREASE INTO THE AFTERNOON WITH SUSTAINED NEAR 30 KNOTS AND GUSTS NEAR OR ABOVE 40 KNOTS. AS HAS BEEN THE CASE RECENTLY DUE TO THE DRY CONDITIONS...EXPECT SOME BLOWING DUST TO REDUCE VISIBILITIES...MAINLY AT KGLD...INTO THE MVFR CATEGORY. ISOLATED THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON TO EARLY EVENING. SINCE THIS FALLS DURING THE LATER HALF OF THE PERIOD AND UNCERTAINTY IN REGARDS TO TIMING/AREA OF INITIATION...CHOSE TO HANDLE WITH ONLY A CB MENTION AT THIS TIME. && .FIRE WEATHER... ISSUED AT 143 AM MDT MON MAR 26 2012 CRITICAL TO EXTREMELY CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED TODAY...MAINLY ALONG AND WEST OF THE KANSAS AND COLORADO STATE LINE AS A DRYLINE SLOWLY ADVANCES TO THE EAST TODAY. STRONG SOUTHERLY WINDS OF 25 TO 35 MPH WITH GUSTS TO AROUND 55 MPH WILL COMBINE WITH HUMIDITIES AROUND 10 PERCENT DURING THE AFTERNOON AND EARLY EVENING HOURS. A COLD FRONT WILL BEGIN TO MOVE ACROSS THE AREA TONIGHT...BRINGING A SUDDEN SHIFT IN THE WINDS AND A BRIEF PERIOD OF STRONG NORTHWESTERLY WINDS. A VERY DRY AIR MASS WILL SETTLE OVER THE AREA ON TUESDAY BRINGING HUMIDITIES DOWN TO AROUND 15 PERCENT DURING THE AFTERNOON. WHILE WINDS WILL BE LIGHT AND VARIABLE ACROSS MUCH OF THE AREA...THERE IS POTENTIAL FOR STRONGER WINDS AND CRITICAL FIRE WEATHER CONDITIONS ACROSS SOUTHWEST NEBRASKA. IF WINDS DO OCCUR...WILL LIKELY BE A MUCH SMALLER MAGNITUDE OF EVENT THAN TODAY AND CHOSE TO NOT ISSUE A FIRE WEATHER WATCH TO AVOID CONFUSION ABOUT TODAYS WARNING. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ252>254. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ090>092. KS...RED FLAG WARNING FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001-013-027-041. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001>004-013>016-027>029-041-042. NE...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ079. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ SHORT TERM...JRM LONG TERM....024 AVIATION...BULLER FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
100 AM MDT MON MAR 26 2012 .UPDATE... ISSUED AT 836 PM MDT SUN MAR 25 2012 JUST COMPLETED ANOTHER UPDATE. BASED ON CURRENT SATELLITE AND EXPECTED MID/UPPER LEVEL CLOUD COVER AND LOW LEVEL STRATUS...INCREASED CLOUD COVER ONCE AGAIN. ALSO DEWPOINTS ARE RUNNING HIGHER THAN CURRENTLY PROGGED. LOOKS LIKE WINDS WILL SHIFT UNTIL LATER IN THE NIGHT PER THE RUC WHICH HAS A GOOD HANDLE ON THE CURRENT WIND AND DEWPOINT FIELD...ALTHOUGH NOT AS GOOD ON THE DEWPOINTS. SO USED IT FOR THE BASIS OF THE UPDATE. AS A RESULT OF A LONGER PERIOD OF EASTERLY FLOW AND HIGHER DEWPOINTS...INCREASED COVERAGE OF FOG ONCE AGAIN TO AREAS OVER THE NORTHERN PORTION OF THE AREA. AT THIS TIME BASED ON THE THICK MID/UPPER LEVEL CLOUD COVER...DO NOT EXPECT THE FOG TO BECOME DENSE BUT THIS WILL NEED CONTINUED MONITORING. UPDATE ISSUED AT 546 PM MDT SUN MAR 25 2012 JUST COMPLETED A MINOR UPDATE. A GREAT DEAL OF MID/HIGH LEVEL CLOUD COVER MOVING OVER THE AREA IN ADVANCE OF WESTERN UPPER TROUGH. MOISTURE PROGS WOULD INDICATE THAT THIS CLOUD COVER WILL STAY AS THICK AS IT IS NOW OR GET THICKER. SO INCREASED CLOUD COVER THROUGH THE NIGHT. BASED ON LATEST OBSERVATIONS AND MODEL DATA...EXPANDED THE PATCHY FOG AREA TO THE NORTH AND WEST. EVEN THOUGH LOW LEVEL MOISTURE LOOKS TO BE GREATER THAN LAST NIGHT... THE HIGHER LEVEL CLOUD COVER AND INCREASE/VEERING OF THE WIND OVERNIGHT SHOULD LIMIT THE COVERAGE OF THE FOG AND CHANCES THAT IT WILL BE DENSE. WILL CONTINUE TO CLOSELY WATCH TRENDS ON THIS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 308 PM MDT SUN MAR 25 2012 MOIST AIR MASS CONTINUES TO RESIDE OVER THE TRI-STATE REGION THIS AFTERNOON AHEAD OF A TROUGH WHICH IS CURRENTLY SITUATED OVER THE PACIFIC COAST. PRIMARY QUESTION FOR TONIGHT IS WHETHER FOG WILL REFORM ACROSS THE AREA. GUIDANCE IS DEPICTING ANYTHING BUT A CONSENSUS WITH RUC MORE WIDESPREAD THAN MOST OTHER GUIDANCE. WILL CONTINUE WITH PATCHY FOG MENTION OVER THE NORTHEAST BUT EVENING SHIFT WILL NEED TO MONITOR SITUATION CLOSELY. FOCUS THEN SHIFTS TO AN ACTIVE WEATHER DAY ON MONDAY WITH A MULTITUDE OF HAZARDS POSSIBLE ACROSS THE AREA. CONFIDENCE IN CRITICAL FIRE WEATHER CONDITIONS IS HIGHEST ACROSS EASTERN COLORADO. SEE FIRE WEATHER SECTION BELOW FOR FURTHER DISCUSSION ON THAT POTENTIAL. WESTERN CONUS TROUGH WILL BEGIN TO TRANSLATE EASTWARD WITH A SHORTWAVE TROUGH LIFTING NORTHEASTWARD INTO THE WESTERN DAKOTAS BY MONDAY EVENING. A DRYLINE WILL BECOME ESTABLISHED OVER EASTERN COLORADO DURING THE LATE MORNING HOURS BUT DOES NOT REALLY MIX EAST OF THE CO/KS BORDER UNTIL LATE MONDAY EVENING. PRESSURE GRADIENT WILL TIGHTEN RAPIDLY AS THE LOW BEGINS TO DEEPEN RESULTING IN ADVISORY CRITERIA WINDS ACROSS THE ENTIRE FORECAST AREA DURING THE AFTERNOON AND EARLY EVENING. HAVE GONE AHEAD AND EXPANDED THE GOING WIND ADVISORY FOR THIS LIKELIHOOD. IN ADDITION TO FIRE WEATHER AND WIND CONCERNS...ALSO HAVE A SMALL CHANCE FOR THUNDERSTORMS TO DEVELOP PRIMARILY ACROSS NORTHWEST KANSAS AND SOUTHWEST NEBRASKA. STRONGEST DYNAMIC REMAIN NORTH OF THE FORECAST AREA BUT ENOUGH FORCING FOR ASCENT SHOULD BE OBSERVED FOR A FEW HOUR WINDOW. NOT COMPLETELY CONFIDENT THAT CONVECTION WILL DEVELOP BUT THE ENVIRONMENT WOULD BE SUPPORTIVE OF STRONG THUNDERSTORMS IF AN UPDRAFT CAN DEVELOP AND BE SUSTAINED. A COLD FRONT SWEEPS THROUGH THE AREA BETWEEN 00Z AND 06Z. MAY HAVE A BRIEF PERIOD OF GUSTY NORTHWESTERLY WINDS BEHIND THE FRONT GIVEN ANTICIPATED 6 HOUR PRESSURE RISES AS PROGGED BY BOTH THE NAM AND GFS. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 1254 AM MDT MON MAR 26 2012 ZONAL FLOW WILL BE IN PLACE ACROSS THE CONUS TO START THIS PERIOD. WEAK SHORTWAVE TROUGHS WILL BE MOVING ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS BOTH THURSDAY AND FRIDAY. APPEARS THERE WILL BE AT LEAST SOME MOISTURE AVAILABLE AND COUPLED WITH WEAK INSTABILITY WILL CARRY SLIGHT TO LOW CHANCE POPS FOR AFTERNOON/EVENING THUNDERSTORMS BOTH DAYS. UPPER RIDGE WILL BUILD ACROSS THE PLAINS FOR THE REMAINDER OF THE PERIOD AHEAD OF STRONG SYSTEM DIGGING INTO THE FOUR CORNERS. MODEL SOLUTIONS DIVERGE ON HOW TO HANDLE THAT SYSTEM VERY LATE IN THE PERIOD...SO WILL NOT CARRY ANY MENTION OF PRECIPITATION ATTM. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE ENTIRE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1145 PM MDT SUN MAR 25 2012 LOT OF CHANGES/THINGS TO CONSIDER FOR THIS SET OF TAFS. BEFORE THE STRONGER WINDS DEVELOP...IFR/MVFR CEILINGS/VISIBILITIES EXPECTED AT KMCK. BY 14Z VFR CONDITIONS ARE EXPECTED TO RETURN TO KMCK. SOUTHERLY WINDS ARE THEN EXPECTED TO INCREASE INTO THE AFTERNOON WITH SUSTAINED NEAR 30 KNOTS AND GUSTS NEAR OR ABOVE 40 KNOTS. AS HAS BEEN THE CASE RECENTLY DUE TO THE DRY CONDITIONS...EXPECT SOME BLOWING DUST TO REDUCE VISIBILITIES...MAINLY AT KGLD...INTO THE MVFR CATEGORY. ISOLATED THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON TO EARLY EVENING. SINCE THIS FALLS DURING THE LATER HALF OF THE PERIOD AND UNCERTAINTY IN REGARDS TO TIMING/AREA OF INITIATION...CHOSE TO HANDLE WITH ONLY A CB MENTION AT THIS TIME. && .CLIMATE... ISSUED AT 308 PM MDT SUN MAR 25 2012 STILL LOOKING AT THE POTENTIAL FOR A FEW RECORDS ACROSS THE TRI- STATE REGION ON MONDAY. ALSO STILL WELL ON TRACK FOR THE WARMEST MARCH ON RECORD AT GOODLAND...BURLINGTON...AND MCCOOK. HERE ARE THE LATEST FIGURES THROUGH MARCH 24. GOODLAND - 48.8 DEGREES SET IN 1907 - CURRENT AVERAGE TEMP 48.6 BURLINGTON - 47.7 DEGREES SET IN 1986 - CURRENT AVERAGE TEMP 47.1 MCCOOK - 48.3 DEGREES SET IN 2007 - CURRENT AVERAGE TEMP 49.9 HILL CITY - 54.3 DEGREES SET IN 1910 - CURRENT AVERAGE TEMP 51.1 WITH MUCH ABOVE NORMAL TEMPERATURES PROJECTED TO CONTINUE THROUGH THE END OF THE MONTH...CONFIDENCE IS VERY HIGH THAT GOODLAND...BURLINGTON...AND MCCOOK WILL SEE THE WARMEST MARCH ON RECORD. IT REMAINS TO BE SEE IF HILL CITY WILL BREAK THE RECORD AS WELL. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ090>092. RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ252>254. KS...FIRE WEATHER WATCH FROM NOON MDT /1 PM CDT/ TODAY THROUGH THIS EVENING FOR KSZ001-013-027-041. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR KSZ001>004-013>016-027>029-041-042. NE...FIRE WEATHER WATCH FROM NOON MDT TODAY THROUGH THIS EVENING FOR NEZ079. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TODAY TO 9 PM MDT /10 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ UPDATE...BULLER SHORT TERM...PMM/FOLTZ LONG TERM....024 AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1151 PM MDT SUN MAR 25 2012 .UPDATE... ISSUED AT 836 PM MDT SUN MAR 25 2012 JUST COMPLETED ANOTHER UPDATE. BASED ON CURRENT SATELLITE AND EXPECTED MID/UPPER LEVEL CLOUD COVER AND LOW LEVEL STRATUS...INCREASED CLOUD COVER ONCE AGAIN. ALSO DEWPOINTS ARE RUNNING HIGHER THAN CURRENTLY PROGGED. LOOKS LIKE WINDS WILL SHIFT UNTIL LATER IN THE NIGHT PER THE RUC WHICH HAS A GOOD HANDLE ON THE CURRENT WIND AND DEWPOINT FIELD...ALTHOUGH NOT AS GOOD ON THE DEWPOINTS. SO USED IT FOR THE BASIS OF THE UPDATE. AS A RESULT OF A LONGER PERIOD OF EASTERLY FLOW AND HIGHER DEWPOINTS...INCREASED COVERAGE OF FOG ONCE AGAIN TO AREAS OVER THE NORTHERN PORTION OF THE AREA. AT THIS TIME BASED ON THE THICK MID/UPPER LEVEL CLOUD COVER...DO NOT EXPECT THE FOG TO BECOME DENSE BUT THIS WILL NEED CONTINUED MONITORING. UPDATE ISSUED AT 546 PM MDT SUN MAR 25 2012 JUST COMPLETED A MINOR UPDATE. A GREAT DEAL OF MID/HIGH LEVEL CLOUD COVER MOVING OVER THE AREA IN ADVANCE OF WESTERN UPPER TROUGH. MOISTURE PROGS WOULD INDICATE THAT THIS CLOUD COVER WILL STAY AS THICK AS IT IS NOW OR GET THICKER. SO INCREASED CLOUD COVER THROUGH THE NIGHT. BASED ON LATEST OBSERVATIONS AND MODEL DATA...EXPANDED THE PATCHY FOG AREA TO THE NORTH AND WEST. EVEN THOUGH LOW LEVEL MOISTURE LOOKS TO BE GREATER THAN LAST NIGHT... THE HIGHER LEVEL CLOUD COVER AND INCREASE/VEERING OF THE WIND OVERNIGHT SHOULD LIMIT THE COVERAGE OF THE FOG AND CHANCES THAT IT WILL BE DENSE. WILL CONTINUE TO CLOSELY WATCH TRENDS ON THIS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 308 PM MDT SUN MAR 25 2012 MOIST AIR MASS CONTINUES TO RESIDE OVER THE TRI-STATE REGION THIS AFTERNOON AHEAD OF A TROUGH WHICH IS CURRENTLY SITUATED OVER THE PACIFIC COAST. PRIMARY QUESTION FOR TONIGHT IS WHETHER FOG WILL REFORM ACROSS THE AREA. GUIDANCE IS DEPICTING ANYTHING BUT A CONSENSUS WITH RUC MORE WIDESPREAD THAN MOST OTHER GUIDANCE. WILL CONTINUE WITH PATCHY FOG MENTION OVER THE NORTHEAST BUT EVENING SHIFT WILL NEED TO MONITOR SITUATION CLOSELY. FOCUS THEN SHIFTS TO AN ACTIVE WEATHER DAY ON MONDAY WITH A MULTITUDE OF HAZARDS POSSIBLE ACROSS THE AREA. CONFIDENCE IN CRITICAL FIRE WEATHER CONDITIONS IS HIGHEST ACROSS EASTERN COLORADO. SEE FIRE WEATHER SECTION BELOW FOR FURTHER DISCUSSION ON THAT POTENTIAL. WESTERN CONUS TROUGH WILL BEGIN TO TRANSLATE EASTWARD WITH A SHORTWAVE TROUGH LIFTING NORTHEASTWARD INTO THE WESTERN DAKOTAS BY MONDAY EVENING. A DRYLINE WILL BECOME ESTABLISHED OVER EASTERN COLORADO DURING THE LATE MORNING HOURS BUT DOES NOT REALLY MIX EAST OF THE CO/KS BORDER UNTIL LATE MONDAY EVENING. PRESSURE GRADIENT WILL TIGHTEN RAPIDLY AS THE LOW BEGINS TO DEEPEN RESULTING IN ADVISORY CRITERIA WINDS ACROSS THE ENTIRE FORECAST AREA DURING THE AFTERNOON AND EARLY EVENING. HAVE GONE AHEAD AND EXPANDED THE GOING WIND ADVISORY FOR THIS LIKELIHOOD. IN ADDITION TO FIRE WEATHER AND WIND CONCERNS...ALSO HAVE A SMALL CHANCE FOR THUNDERSTORMS TO DEVELOP PRIMARILY ACROSS NORTHWEST KANSAS AND SOUTHWEST NEBRASKA. STRONGEST DYNAMIC REMAIN NORTH OF THE FORECAST AREA BUT ENOUGH FORCING FOR ASCENT SHOULD BE OBSERVED FOR A FEW HOUR WINDOW. NOT COMPLETELY CONFIDENT THAT CONVECTION WILL DEVELOP BUT THE ENVIRONMENT WOULD BE SUPPORTIVE OF STRONG THUNDERSTORMS IF AN UPDRAFT CAN DEVELOP AND BE SUSTAINED. A COLD FRONT SWEEPS THROUGH THE AREA BETWEEN 00Z AND 06Z. MAY HAVE A BRIEF PERIOD OF GUSTY NORTHWESTERLY WINDS BEHIND THE FRONT GIVEN ANTICIPATED 6 HOUR PRESSURE RISES AS PROGGED BY BOTH THE NAM AND GFS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 308 PM MDT SUN MAR 25 2012 DRY CONDITIONS AND A CONTINUATION OF MUCH ABOVE NORMAL TEMPERATURES WILL CONTINUE FROM TUESDAY THROUGH EARLY THURSDAY AS A BROAD MID/UPPER RIDGE BUILDS BACK ACROSS THE CENTRAL HIGH PLAINS. BY THURSDAY AFTERNOON...FORCING FOR ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH TRANSLATING ACROSS THE DAKOTAS COULD PROVIDE ENOUGH LIFT TO GENERATE CONVECTION ACROSS PRIMARILY NORTHEASTERN PORTIONS OF THE TRI-STATE REGION. ADDITIONAL WEAK SHORTWAVE TROUGHS PASS THROUGH THE AREA THURSDAY NIGHT AND FRIDAY WITH A CONTINUED FOCUS ON EASTERN PORTIONS OF THE AREA. DRY CONDITIONS WILL RETURN FOR THE WEEKEND WITH AFTERNOON TEMPS IN THE MID TO UPPER 70S CONTINUING. SIGNIFICANT FORECAST UNCERTAINTY DEVELOPS BY SUNDAY WITH THE OPERATIONAL GFS/GEFS MEAN AND EC DEPICTING STARKLY DIFFERENT SCENARIOS. THE GFS ATTEMPTS TO DEVELOP A DEEP TROUGH ACROSS THE GREAT BASIN/INTERMOUNTAIN WEST WHILE THE EC SUPPORTS A RIDGE OVER THE SAME GENERAL AREA AND HOLDS THE TROUGH OVER THE PACIFIC NORTHWEST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1145 PM MDT SUN MAR 25 2012 LOT OF CHANGES/THINGS TO CONSIDER FOR THIS SET OF TAFS. BEFORE THE STRONGER WINDS DEVELOP...IFR/MVFR CEILINGS/VISIBILITIES EXPECTED AT KMCK. BY 14Z VFR CONDITIONS ARE EXPECTED TO RETURN TO KMCK. SOUTHERLY WINDS ARE THEN EXPECTED TO INCREASE INTO THE AFTERNOON WITH SUSTAINED NEAR 30 KNOTS AND GUSTS NEAR OR ABOVE 40 KNOTS. AS HAS BEEN THE CASE RECENTLY DUE TO THE DRY CONDITIONS...EXPECT SOME BLOWING DUST TO REDUCE VISIBILITIES...MAINLY AT KGLD...INTO THE MVFR CATEGORY. ISOLATED THUNDERSTORMS ARE EXPECTED IN THE AFTERNOON TO EARLY EVENING. SINCE THIS FALLS DURING THE LATER HALF OF THE PERIOD AND UNCERTAINTY IN REGARDS TO TIMING/AREA OF INITIATION...CHOSE TO HANDLE WITH ONLY A CB MENTION AT THIS TIME. && .FIRE WEATHER... ISSUED AT 308 PM MDT SUN MAR 25 2012 HAVE GONE AHEAD AND UPGRADED THE THREE EASTERN COLORADO COUNTIES TO A RED FLAG WARNING FOR MONDAY. LEFT THE FIRE WEATHER WATCH INTACT FOR THE FIRST TIER OF KANSAS AND NEBRASKA COUNTIES AS THERE IS SIGNIFICANT UNCERTAINTY WITH REGARD TO JUST HOW FAR EAST THE DRYLINE WILL MIX DURING THE AFTERNOON. OPTED TO CANCEL THE FIRE WEATHER WATCH FOR THE NEXT TIER OF COUNTIES TO THE EAST AS CONFIDENCE WAS TOO LOW THAT CRITERIA WOULD BE MET IN THESE LOCATIONS. && .CLIMATE... ISSUED AT 308 PM MDT SUN MAR 25 2012 STILL LOOKING AT THE POTENTIAL FOR A FEW RECORDS ACROSS THE TRI- STATE REGION ON MONDAY. ALSO STILL WELL ON TRACK FOR THE WARMEST MARCH ON RECORD AT GOODLAND...BURLINGTON...AND MCCOOK. HERE ARE THE LATEST FIGURES THROUGH MARCH 24. GOODLAND - 48.8 DEGREES SET IN 1907 - CURRENT AVERAGE TEMP 48.6 BURLINGTON - 47.7 DEGREES SET IN 1986 - CURRENT AVERAGE TEMP 47.1 MCCOOK - 48.3 DEGREES SET IN 2007 - CURRENT AVERAGE TEMP 49.9 HILL CITY - 54.3 DEGREES SET IN 1910 - CURRENT AVERAGE TEMP 51.1 WITH MUCH ABOVE NORMAL TEMPERATURES PROJECTED TO CONTINUE THROUGH THE END OF THE MONTH...CONFIDENCE IS VERY HIGH THAT GOODLAND...BURLINGTON...AND MCCOOK WILL SEE THE WARMEST MARCH ON RECORD. IT REMAINS TO BE SEE IF HILL CITY WILL BREAK THE RECORD AS WELL. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...WIND ADVISORY FROM NOON TO 9 PM MDT MONDAY FOR COZ090>092. RED FLAG WARNING FROM NOON TO 9 PM MDT MONDAY FOR COZ252>254. KS...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR KSZ001-013-027-041. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TO 9 PM MDT /10 PM CDT/ MONDAY FOR KSZ001>004-013>016-027>029-041-042. NE...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR NEZ079. WIND ADVISORY FROM NOON MDT /1 PM CDT/ TO 9 PM MDT /10 PM CDT/ MONDAY FOR NEZ079>081. && $$ UPDATE...BULLER SHORT TERM...PMM/FOLTZ LONG TERM....FOLTZ AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS JACKSON KY
359 AM EDT MON MAR 26 2012 .UPDATE... ISSUED AT 150 AM EDT MON MAR 26 2012 LOW CLOUDS CONTINUE TO GENERALLY ADVECT FROM NNW TO SSE ACROSS THE CWA AT THIS TIME WITH MORE OF A SOLID BAND ACROSS THE SOUTHERN CWA THAT AT THIS POINT STILL SEEMS TO BE ADVECTION OUT AND THEN SOME MORE PATCHY LOW CLOUDS FURTHER NORTH ACROSS SOUTHERN OH AND PARTS OF CENTRAL AND NORTHEASTERN KY THAT GENERALLY ALSO APPEAR TO BE ADVECTING ACROSS RATHER THAN DEVELOPING FURTHER. A RATHER SUBTLE VORT/ SHORTWAVE WILL BE ROTATING ACROSS THE REGION FOR THE REMAINDER OF THE NIGHT AND THIS WILL PROBABLY AT LEAST TEMPORARILY SLOW DOWN THE ADVECTION OF THE MORE SOLID BAND IN THE SOUTH OUT AND COULD LEAD TO SOME FURTHER DEVELOPMENT OF CURRENTLY MORE SCATTERED LOW CLOUDS WORKING IN FROM THE NNW. THE GRIDS WERE UPDATED TO GENERALLY REFLECT THIS THINKING FOR SKY COVER AND TO ACCOUNT FOR THE RECENT OBS TRENDS TO TEMPS...DEWPOINTS AND WINDS. UPDATE ISSUED AT 1050 PM EDT SUN MAR 25 2012 CLOUD DECK AROUND 4K AGL FEET CURRENTLY ADVECTING SOUTH ACROSS THE FORECAST AREA PER LATEST SATELLITE IMAGERY. BACK EDGE OF THIS CLOUD DECK WILL CLEAR THE NORTHERN PART OF FORECAST AREA BY MIDNIGHT. HOWEVER...WITH CONTINUED NORTHERLY FLOW AND LOW LEVEL MOISTURE AVAILABLE EXPECT UPSLOPE FLOW TO KEEP CLOUDS IN THE SOUTHEAST PART OF FORECAST AREA FOR MOST OF THE NIGHT. THIS IDEA IS SUPPORTED BY LATEST RUC GUIDANCE. HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS PER LATEST SATELLITE AND OBSERVATIONAL DATA. UPDATE ISSUED AT 759 PM EDT SUN MAR 25 2012 THE LAST ISOLATED SHOWERS DISSIPATED OR MOVED OUT OF THE AREA AROUND 730 PM EDT...SO HAVE REMOVED ALL PRECIPITATION FROM THE NDFD AND ASSOCIATED PRODUCTS FOR THE OVERNIGHT PERIOD. ALSO MADE SOME MINOR UPDATES BASED ON LATEST OBSERVATIONAL TRENDS. THE MAIN FORECAST ISSUE IS HOW MUCH CLOUDINESS THERE WILL BE OVERNIGHT. THERE IS CONSIDERABLE LOW CLOUDINESS UPSTREAM OF THE AREA...AND LATEST NAM AND RUC GUIDANCE SHOW CONSIDERABLE LOW LEVEL MOISTURE...MAINLY BELOW 850 MB TO BE OVER THE AREA TONIGHT. WITH NORTHERLY FLOW EXPECT CLOUDINESS TO INCREASE IN COVERAGE DURING THE NIGHT...WITH MOSTLY CLOUDY SKIES BEING THE RESULT. UPDATE ISSUED AT 423 PM EDT SUN MAR 25 2012 BASED ON RADAR TRENDS ISOLATED TO SCATTERED SHOWERS WILL AFFECT FAR EASTERN KENTUCKY THROUGH 23Z. THIS IS CURRENTLY WELL DEPICTED IN NDFD. ONLY SOME MINOR NDFD UPDATES WERE MADE BASED ON LATEST SATELLITE AND SURFACE OBSERVATIONAL TRENDS. && .SHORT TERM...(LATE THIS AFTERNOON THROUGH TUESDAY) ISSUED AT 310 PM EDT SUN MAR 25 2012 UPPER LEVEL LOW WILL CONTINUE TO PULL AWAY FROM THE AREA TONIGHT GIVING WAY TO UPPER LEVEL RIDGING THROUGH THE REMAINDER OF THE PERIOD. THE UPPER LOW WILL REMAIN CLOSE ENOUGH TO KEEP A MENTION OF A FEW SHOWERS IN THE FORECAST FOR MOST AREAS LATE THIS AFTERNOON... WITH THE CHANCE OF SHOWERS LINGERING ACROSS THE TIP OF FAR EAST KENTUCKY THIS EVENING. IT APPEARS THAT INSTABILITY WILL NOT BE SUFFICIENT TO PRODUCE A TSTORM THIS FAR WEST SO REMOVED THAT MENTION FOR THIS AFTERNOON AND EVENING. A COLD FRONT WILL THEN DROP IN FROM THE NORTH LATE TONIGHT KEEPING A LIGHT BREEZE BLOWING FOR MOST LOCATIONS. MOISTURE POOLING ALONG THIS BOUNDARY IN CONJUNCTION WITH THE LIGHT NORTHEAST LOW LEVEL FLOW WILL LIKELY RESULT IN QUITE A BIT OF STRATUS DEVELOPING OVERNIGHT WITH MAYBE EVEN A LITTLE DRIZZLE. ANY CLOUD COVER SHOULD DISSOLVE BY MIDDAY MONDAY AS HIGH PRESSURE BEGINS TO BUILD DOWN INTO THE OHIO VALLEY ACCOMPANIED BY A MUCH DRIER AIRMASS. IN FACT...DEWPOINTS ARE PROGGED TO DROP INTO THE 20S OVER NORTHEAST KENTUCKY LATE MONDAY NIGHT AND THERE IS A CONCERN THAT TEMPERATURES WILL RESPOND TO THIS DRY AIR AND DROP LOW ENOUGH TO THREATEN A FROST OR FREEZE FOR SOME AREAS. CONFIDENCE IS NOT HIGH ENOUGH TO HOIST ANY HEADLINES AT THIS TIME THOUGH AS MODELS INDICATE THE POTENTIAL FOR SOME HIGH LEVEL CLOUDINESS TO MOVE IN OVERNIGHT AND POINT TO THERE BEING JUST ENOUGH WIND TO KEEP ANY FROST FORMATION ISOLATED AND CONFINED TO THE DEEPEST VALLEYS BASICALLY NORTH AND EAST OF JKL. HIGH PRESSURE WILL REMAIN IN CONTROL ON TUESDAY BUT HIGH LEVEL CLOUDS WILL BE ON THE INCREASE IN ADVANCE OF OUR NEXT WEATHER MAKER. TEMPS ARE TRICKY...VARYING 10 TO 15 DEGREES BETWEEN THE GFS AND NAM MOS AT ANY GIVEN POINT. TEND TO AGREE MORE WITH THE GFS NUMBERS WITH THE UPPER LEVEL RIDGE BUILDING IN AND WILL FORECAST HIGHS APPROACHING OR EXCEEDING 70 FOR MOST LOCATIONS. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 359 AM EDT MON MAR 26 2012 THE EXTENDED FORECAST PERIOD BEGINS WEDNESDAY WITH AN ACTIVE PATTERN IN STORE. A RATHER VIGOROUS SHORTWAVE WILL TRACK ACROSS THE NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. AT THE SURFACE...A COLD FRONT MOVES SOUTH AND EAST INTO KENTUCKY. A SURFACE HIGH OVER THE SOUTHEAST WILL IMPEDE THE PROGRESS OF THE FRONT NEARLY SHEARING IT OUT. THE SHORT TERM MODELS ARE IN FAIR AGREEMENT WITH THIS FEATURE AS WELL. WITH THE SLOWED APPROACH OF THE FRONT AND THE DRY ENVIRONMENT ALREADY IN PLACE...FEEL THAT THE NAM HAS A GOOD HANDLE ON THE BULK OF THE PRECIP MOVING INTO THE AREA TOWARDS LATE MORNING AND INTO THE AFTERNOON. MODEL SOUNDINGS STILL INDICATE A FAIR AMOUNT OF INSTABILITY AS MOST OF THE FORCING ARRIVES DURING THE AFTERNOON DURING MAX HEATING. SO WILL PUT THUNDERSTORMS IN WITH THE PRECIP. IT IS STILL UNCLEAR AT THIS POINT IF THERE IS A THREAT FOR SEVERE STORMS AS ALOT OF THE ENERGY SEEMS TO GET LOST OR STAYS NORTH AS THE FRONT MOVES SOUTH. DUE TO THE PROGRESSION OF THE FRONT...A MODEL COMPROMISE HAS PRECIP LASTING A BIT LONGER AS THE FRONT DOESNT EXIT TILL LATE THURSDAY. THIS IS A BIT CONCERNING AS TENDENCY LIES WITH PRECIP HANGING AROUND A BIT LONGER IN THE SOUTHERN COUNTIES BUT WILL LEAVE THIS DECISION WITH SHIFTS A LITTLE CLOSER TO THE EVENT. DRY WEATHER WILL RETURN TO EASTERN KENTUCKY THURSDAY NIGHT AND INTO FRIDAY AS A RIDGE MOVES OVER THE OHIO VALLEY. THIS IS HOWEVER SHORT LIVED AS ANOTHER STRONG WAVE MOVES ACROSS THE NORTHERN PLAINS AND INTO THE GREAT LAKES. THIS IS OCCURRING WHILE ANOTHER WAVE EJECTS OUT OF THE SOUTHWEST AND INTO THE NORTHERN GULF. THIS WILL INJECT A SUFFICIENT MOISTURE FLUX FROM THE GULF INTO THE TN AND OH VALLEYS. ALSO...AT THIS POINT THE GFS AND EURO DO DIVERGE IN THEIR RESPECTIVE SOLUTIONS WITH THE EURO BEING FASTER THAN THE GFS BRINGING PRECIP INTO THE AREA FRIDAY AFTERNOON WHERE THE GFS WAITS TILL FRIDAY NIGHT. A CONSENSUS BETWEEN THE TWO IN THE CR INITIALIZATION HAS SLIGHT CHANCE POPS LATE FRIDAY THEN PROGRESSING THROUGH SO WILL KEEP THIS IN THERE. THROUGH THE REST OF THE WEEKEND...THE DEVELOPING SURFACE BOUNDARY...SUFFICIENT UPPER LEVEL SUPPORT AND STRONG MOISTURE FLUX WILL PRETTY MUCH KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST. DUE TO THE PROGRESSIVE PATTERN THOUGH...DO NOT EXPECT ANY PROLONGED RAINFALLS. OVERALL...THE LATTER HALF OF THE EXTENDED APPEARS TO BE STILL A BIT MURKY DUE TO THE PROGRESSIVE PATTERN AND THE FLIP FLOPPING OF THE MODELS SO WILL EXUDE A LOW CONFIDENCE ESPECIALLY DAY 6 AND 7. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 150 AM EDT MON MAR 26 2012 MAIN ISSUE OF CONCERN FOR THIS TAF ISSUANCE AND THE FIRST 6 TO 12 HOURS OF THE PERIOD CONTINUES TO BE THE MOVEMENT OF LOW CLOUDS ACROSS THE AREA AND THE POTENTIAL FOR DEVELOPMENT OF LOW CLOUDS ACROSS THE FORECAST AREA DURING THE NEXT 6 TO 9 HRS AS A RATHER SUBTLE SHORTWAVE MOVES ACROSS THE AREA. THERE IS CONSIDERABLE LOW LEVEL CLOUDINESS ACROSS THE SOUTHERN CWA AT THIS TIME AND MORE ISOLATED TO SCATTERED PATCHES OF LOW CLOUDS ADVECTING IN FORM THE NORTH. AT THIS POINT ALL OF THE CLOUDS SEEM TO GENERALLY BE ADVECTING ACROSS THE AREA...BUT THE SHORTWAVE PASSING BY DURING THE NEXT 6 HRS OR SO MAY SLOW DOWN ADVECTION OF THE LOW CLOUDS OUT OF THE SOUTH AND POSSIBLE LEAD TO FURTHER DEVELOPMENT OF THE BANDS WORKING IN FROM THE NORTH AS THE MOVE ACROSS THE JKL CWA. AT THIS POINT...NAMBUFR SOUNDINGS SEEM TO INDICATE PREVAILING CLOUD HEIGHTS OF THE LOW CLOUDS MOSTLY IN THE VFR RANGE WITH SOME MVFR IN THE HIGHER TERRAIN NEAR THE VA BORDER. A BRIEF PERIOD OF A DROP TO MVFR CLOUD OCCUR AT EITHER OF THE THREE TAF SITES...BUT CURRENT THINKING IS THAT THIS WOULD BE SHORT LIVED AND CONFIDENCE IN THIS WAS TOO LOW FOR ANY TEMPOS AT THIS POINT. AT THIS POINT VFR IS EXPECTED DURING THE FIRST 6 TO 12 HRS OF THE PERIOD... THUS VFR SHOULD PREVAIL THE ENTIRE PERIOD AT THE TAF SITES. && .JKL WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY FROM 2 AM TO 10 AM EDT TUESDAY FOR KYZ044-050>052- 058>060-068-069-080-086>088-104-106>120. && $$ UPDATE...JP SHORT TERM...ABE LONG TERM....SHALLENBERGER AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
157 AM EDT MON MAR 26 2012 .UPDATE... ISSUED AT 150 AM EDT MON MAR 26 2012 LOW CLOUDS CONTINUE TO GENERALLY ADVECT FROM NNW TO SSE ACROSS THE CWA AT THIS TIME WITH MORE OF A SOLID BAND ACROSS THE SOUTHERN CWA THAT AT THIS POINT STILL SEEMS TO BE ADVECTION OUT AND THEN SOME MORE PATCHY LOW CLOUDS FURTHER NORTH ACROSS SOUTHERN OH AND PARTS OF CENTRAL AND NORTHEASTERN KY THAT GENERALLY ALSO APPEAR TO BE ADVECTING ACROSS RATHER THAN DEVELOPING FURTHER. A RATHER SUBTLE VORT/ SHORTWAVE WILL BE ROTATING ACROSS THE REGION FOR THE REMAINDER OF THE NIGHT AND THIS WILL PROBABLY AT LEAST TEMPORARILY SLOW DOWN THE ADVECTION OF THE MORE SOLID BAND IN THE SOUTH OUT AND COULD LEAD TO SOME FURTHER DEVELOPMENT OF CURRENTLY MORE SCATTERED LOW CLOUDS WORKING IN FROM THE NNW. THE GRIDS WERE UPDATED TO GENERALLY REFLECT THIS THINKING FOR SKY COVER AND TO ACCOUNT FOR THE RECENT OBS TRENDS TO TEMPS...DEWPOINTS AND WINDS. UPDATE ISSUED AT 1050 PM EDT SUN MAR 25 2012 CLOUD DECK AROUND 4K AGL FEET CURRENTLY ADVECTING SOUTH ACROSS THE FORECAST AREA PER LATEST SATELLITE IMAGERY. BACK EDGE OF THIS CLOUD DECK WILL CLEAR THE NORTHERN PART OF FORECAST AREA BY MIDNIGHT. HOWEVER...WITH CONTINUED NORTHERLY FLOW AND LOW LEVEL MOISTURE AVAILABLE EXPECT UPSLOPE FLOW TO KEEP CLOUDS IN THE SOUTHEAST PART OF FORECAST AREA FOR MOST OF THE NIGHT. THIS IDEA IS SUPPORTED BY LATEST RUC GUIDANCE. HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS PER LATEST SATELLITE AND OBSERVATIONAL DATA. UPDATE ISSUED AT 759 PM EDT SUN MAR 25 2012 THE LAST ISOLATED SHOWERS DISSIPATED OR MOVED OUT OF THE AREA AROUND 730 PM EDT...SO HAVE REMOVED ALL PRECIPITATION FROM THE NDFD AND ASSOCIATED PRODUCTS FOR THE OVERNIGHT PERIOD. ALSO MADE SOME MINOR UPDATES BASED ON LATEST OBSERVATIONAL TRENDS. THE MAIN FORECAST ISSUE IS HOW MUCH CLOUDINESS THERE WILL BE OVERNIGHT. THERE IS CONSIDERABLE LOW CLOUDINESS UPSTREAM OF THE AREA...AND LATEST NAM AND RUC GUIDANCE SHOW CONSIDERABLE LOW LEVEL MOISTURE...MAINLY BELOW 850 MB TO BE OVER THE AREA TONIGHT. WITH NORTHERLY FLOW EXPECT CLOUDINESS TO INCREASE IN COVERAGE DURING THE NIGHT...WITH MOSTLY CLOUDY SKIES BEING THE RESULT. UPDATE ISSUED AT 423 PM EDT SUN MAR 25 2012 BASED ON RADAR TRENDS ISOLATED TO SCATTERED SHOWERS WILL AFFECT FAR EASTERN KENTUCKY THROUGH 23Z. THIS IS CURRENTLY WELL DEPICTED IN NDFD. ONLY SOME MINOR NDFD UPDATES WERE MADE BASED ON LATEST SATELLITE AND SURFACE OBSERVATIONAL TRENDS. && .SHORT TERM...(LATE THIS AFTERNOON THROUGH TUESDAY) ISSUED AT 310 PM EDT SUN MAR 25 2012 UPPER LEVEL LOW WILL CONTINUE TO PULL AWAY FROM THE AREA TONIGHT GIVING WAY TO UPPER LEVEL RIDGING THROUGH THE REMAINDER OF THE PERIOD. THE UPPER LOW WILL REMAIN CLOSE ENOUGH TO KEEP A MENTION OF A FEW SHOWERS IN THE FORECAST FOR MOST AREAS LATE THIS AFTERNOON... WITH THE CHANCE OF SHOWERS LINGERING ACROSS THE TIP OF FAR EAST KENTUCKY THIS EVENING. IT APPEARS THAT INSTABILITY WILL NOT BE SUFFICIENT TO PRODUCE A TSTORM THIS FAR WEST SO REMOVED THAT MENTION FOR THIS AFTERNOON AND EVENING. A COLD FRONT WILL THEN DROP IN FROM THE NORTH LATE TONIGHT KEEPING A LIGHT BREEZE BLOWING FOR MOST LOCATIONS. MOISTURE POOLING ALONG THIS BOUNDARY IN CONJUNCTION WITH THE LIGHT NORTHEAST LOW LEVEL FLOW WILL LIKELY RESULT IN QUITE A BIT OF STRATUS DEVELOPING OVERNIGHT WITH MAYBE EVEN A LITTLE DRIZZLE. ANY CLOUD COVER SHOULD DISSOLVE BY MIDDAY MONDAY AS HIGH PRESSURE BEGINS TO BUILD DOWN INTO THE OHIO VALLEY ACCOMPANIED BY A MUCH DRIER AIRMASS. IN FACT...DEWPOINTS ARE PROGGED TO DROP INTO THE 20S OVER NORTHEAST KENTUCKY LATE MONDAY NIGHT AND THERE IS A CONCERN THAT TEMPERATURES WILL RESPOND TO THIS DRY AIR AND DROP LOW ENOUGH TO THREATEN A FROST OR FREEZE FOR SOME AREAS. CONFIDENCE IS NOT HIGH ENOUGH TO HOIST ANY HEADLINES AT THIS TIME THOUGH AS MODELS INDICATE THE POTENTIAL FOR SOME HIGH LEVEL CLOUDINESS TO MOVE IN OVERNIGHT AND POINT TO THERE BEING JUST ENOUGH WIND TO KEEP ANY FROST FORMATION ISOLATED AND CONFINED TO THE DEEPEST VALLEYS BASICALLY NORTH AND EAST OF JKL. HIGH PRESSURE WILL REMAIN IN CONTROL ON TUESDAY BUT HIGH LEVEL CLOUDS WILL BE ON THE INCREASE IN ADVANCE OF OUR NEXT WEATHER MAKER. TEMPS ARE TRICKY...VARYING 10 TO 15 DEGREES BETWEEN THE GFS AND NAM MOS AT ANY GIVEN POINT. TEND TO AGREE MORE WITH THE GFS NUMBERS WITH THE UPPER LEVEL RIDGE BUILDING IN AND WILL FORECAST HIGHS APPROACHING OR EXCEEDING 70 FOR MOST LOCATIONS. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 310 PM EDT SUN MAR 25 2012 MODELS CONTINUE TO DISPLAY GOOD CONTINUITY THRU MOST OF THE WORK WEEK BUT BEGIN TO DIVERGE RATHER SHARPLY ON FRIDAY WITH THE LONG WAVE PATTERN. HAVE GENERALLY FOLLOWED A BLEND OF THE MEDIUM RANGE OPERATIONAL/ENSEMBLE GUIDANCE THRU THE FIRST HALF OF THE PERIOD BEFORE GIVING MORE CREDENCE TO THE LESS EXTREME SOLUTION OF THE GFS OVER THE WEEKEND...THOUGH CONFIDENCE WITH THE DETAILS TOWARDS THE TAIL END OF THE PERIOD REMAINS RATHER LOW. VORTEX CURRENTLY MAKING LANDFALL ALONG THE CA/OR COAST IS EXPECTED TO SEND A DECENT SHORT WAVE OVER THE ROCKIES AND ACROSS THE NRN PLAINS BEFORE REACHING THE UPPER MIDWEST BY TUESDAY NIGHT TO START THE PERIOD. AS THIS WAVE CONTINUES TO PUSH EAST ALONG THE CANADIAN BORDER...THE COLD FRONT ASSOCIATED WITH THE SFC REFLECTION LOOKS TO SWEEP ACROSS THE OHIO RIVER AND INTO ERN KY ON WEDNESDAY...WITH ENOUGH INSTABILITY STILL ADVERTISED IN FCST SOUNDINGS AROUND THE AREA TO WARRANT CHANCES OF THUNDER FOR WEDNESDAY. GIVEN THE PROGRESSIVE NATURE OF THE PATTERN...WOULD PREFER TO GO MOSTLY QUIET BY WEDNESDAY NIGHT BUT WILL SETTLE FOR A GENTLE NUDGE IN THAT DIRECTION FOR THE MOMENT. CANADIAN HIGH PRESSURE BUILDS DOWN ACROSS THE GREAT LAKES AND INTO THE OHIO VALLEY ON THURSDAY...BRINGING ANOTHER BOUT OF BENIGN WEATHER THROUGH FRIDAY...AT WHICH POINT THE MODELS BEGIN PARTING WAYS WITH THEIR DEPICTION OF THE UPPER LEVEL FEATURES. REGARDLESS OF THEIR RESPECTIVE DIFFERENCES...ANY OF THE RECENT OFFINGS FROM THE GUIDANCE WOULD POINT TOWARDS AN UNSETTLED PATTERN PERSISTING THROUGH THE WEEKEND WITH PERIODS OF RAIN POSSIBLE AND A FEW THUNDERSTORMS NOT ENTIRELY OUT OF THE QUESTION. AT THIS TIME...WILL KEEP POPS IN THE LOW END CHANCE RANGE UNTIL A BETTER CONSENSUS CAN BE OBTAINED. TEMPERATURES OVER THE COURSE OF THE PERIOD LOOK TO CONTINUE FOLLOWING THE ABOVE NORMAL TREND...WITH TEMPS EARLY IN THE PERIOD STILL RUNNING WELL ABOVE NORMAL BEFORE TRENDING TOWARDS CLIMO BY THE BEGINNING OF NEXT WEEK. ONE NOTE OF CONCERN IS FOR THURSDAY NIGHT INTO FRIDAY MORNING WHERE AGAIN...MODELS POINT TOWARDS RELATIVELY CLEAR SKIES AND LIGHT WINDS WITH DEWPTS IN THE UPPER 20S AND LOWER 30S THROUGHOUT OUR NERN VALLEYS. HAVE STRAYED TOWARDS THE COOLER SIDE OF THE MOS LOWS FOR NOW AND...GIVEN THE EVOLVING UNCERTAINTY JUST BEYOND THIS WINDOW...WILL CONTINUE TO KEEP A CLOSE EYE ON THESE NUMBERS OVER THE NEXT FEW DAYS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 150 AM EDT MON MAR 26 2012 MAIN ISSUE OF CONCERN FOR THIS TAF ISSUANCE AND THE FIRST 6 TO 12 HOURS OF THE PERIOD CONTINUES TO BE THE MOVEMENT OF LOW CLOUDS ACROSS THE AREA AND THE POTENTIAL FOR DEVELOPMENT OF LOW CLOUDS ACROSS THE FORECAST AREA DURING THE NEXT 6 TO 9 HRS AS A RATHER SUBTLE SHORTWAVE MOVES ACROSS THE AREA. THERE IS CONSIDERABLE LOW LEVEL CLOUDINESS ACROSS THE SOUTHERN CWA AT THIS TIME AND MORE ISOLATED TO SCATTERED PATCHES OF LOW CLOUDS ADVECTING IN FORM THE NORTH. AT THIS POINT ALL OF THE CLOUDS SEEM TO GENERALLY BE ADVECTING ACROSS THE AREA...BUT THE SHORTWAVE PASSING BY DURING THE NEXT 6 HRS OR SO MAY SLOW DOWN ADVECTION OF THE LOW CLOUDS OUT OF THE SOUTH AND POSSIBLE LEAD TO FURTHER DEVELOPMENT OF THE BANDS WORKING IN FROM THE NORTH AS THE MOVE ACROSS THE JKL CWA. AT THIS POINT...NAMBUFR SOUNDINGS SEEM TO INDICATE PREVAILING CLOUD HEIGHTS OF THE LOW CLOUDS MOSTLY IN THE VFR RANGE WITH SOME MVFR IN THE HIGHER TERRAIN NEAR THE VA BORDER. A BRIEF PERIOD OF A DROP TO MVFR CLOUD OCCUR AT EITHER OF THE THREE TAF SITES...BUT CURRENT THINKING IS THAT THIS WOULD BE SHORT LIVED AND CONFIDENCE IN THIS WAS TOO LOW FOR ANY TEMPOS AT THIS POINT. AT THIS POINT VFR IS EXPECTED DURING THE FIRST 6 TO 12 HRS OF THE PERIOD... THUS VFR SHOULD PREVAIL THE ENTIRE PERIOD AT THE TAF SITES. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...ABE LONG TERM....JP AVIATION...JP
AREA FORECAST DISCUSSION
NWS CARIBOU ME
650 PM EDT MON MAR 26 2012 .SYNOPSIS... AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL CROSS THE AREA THIS EVENING. HIGH PRESSURE WILL BUILD EAST TUESDAY...CROSS THE REGION TUESDAY NIGHT...THEN MOVE EAST WEDNESDAY. LOW PRESSURE FROM THE UPPER GREAT LAKES MAY BRING LIGHT PRECIPITATION TO MOSTLY WESTERN AND DOWNEAST PORTIONS OF THE REGION LATE WEDNESDAY INTO THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... UPDATE... SOME CONCERNS THAT WIND ADVISORY MADE BE NEED TO BE MOVED UP AS SOME GUSTS CLOSING CLOSE TO 45-50 MPH MAINLY OVER HIGHER TERRAIN. THE RUC INDICATES WINDS PICKING UP LATER TONIGHT AND CONTINUING INTO MIDDAY TUESDAY AS DOES THE 18Z RUN OF THE NAM. ATTM, WILL KEEP THINGS AS THEY W/WIND ADVISORY. ADJUSTMENTS WERE MADE TO LOWER MINS TONIGHT DOWN A CATEGORY W/SINGLE NUMBERS ACROSS THE FAR N AND W. PREVIOUS DISCUSSION... STRONG LLVL COLD ADVCN ON STIFF NW WINDS DID NOT ALLOW FOR MUCH TEMP RISE THIS AFTN...SO WE HAD TO LOWER AFTN HI TEMPS AGAIN JUST TO GET A REALISTIC HRLY TEMP TREND TO FCST LOWS POSTED ARND 6-7 AM EDT TUE. MDTLY STRONG SFC PRES GRAD WINDS ACROSS ALL OF THE F AND SOME CLDNSS OVR NRN/CNTRL PTNS OF THE REGION TNGT WILL NOT ALLOW FOR ANY XPCTD INVSN TO FORM...SO WE WENT STRAIGHT WITH RAW NAM FCST LOW TEMPS. WE KEPT CHC SN SHWR POPS FOR FAR NRN PTNS OF THE FA FOR THIS EVE AS THE UPPER LOW OVR THE GASPE PNSL MOVES SE INTO NE NB. OTHERWISE...CLDS SHOULD DECREASE OVR THE N AND CNTRL PTNS OF THE FA LATER TNGT INTO ERLY TUE MORN. WINDS...WHICH HAVE BEEN GUSTING AS HIGH AS LOWER 4OS MPH A FEW SITES WILL DIMINISH A LITTLE OVRNGT OVR LOW LYING AREAS...BUT WILL REMAIN FAIRLY STRONG OVR OPEN HIER TRRN AREAS. WINDS ALF... SPCLY IN THE 925-850 MB LAYER WILL INCREASE TO AOA 40 KT LATER TNGT INTO TUE MORN ACROSS THE FA AS THE SFC PRES GRAD REMAINS STRONG BETWEEN SLOWLY DEPARTING LOW PRES IN THE MARITIMES AND HI PRES OVR WRN QB. THIS IN COMBO WITH MSLY SUNNY SKIES XPCTD ACROSS ALL OF THE REGION ON TUE WILL STEEPEN SFC-1 KM LAPSE RATES... ALLOWING POTENTIAL MIX DOWN OF THESE STRONGER WINDS ALF IN GUSTS...BEGINNING SHORTLY AFT DAYBREAK TUE DUE TO THE WEAKNESS OF ANY ESTABLISHED BL TNGT AND CONTG TIL ABOUT SUNSET...AT WHICH TM...WINDS ALF...SFC PRES GRAD AND LLVL INSTABILITY ALL BEGIN DECREASING. WITH ALL OF THIS IN MIND...HI TEMPS TUE AFTN WILL BE LUCKY TO HAVE A 10 TO 15 DEG F DIURNAL RISE FROM LOWS ERLY TUE MORN...RANGING FROM MID 20S XTRM N TO MID TO UPPER 30S DOWNEAST...MAKING TUE QUITE A CONTRAST FROM THE RECORD WARM DAYS OF MID LAST WEEK. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... WINDS WILL DIMINISH TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BRIEFLY SETS UP OVER THE REGION. HOWEVER BY THE OVERNIGHT CLOUDS WILL ALREADY BY ON THE INCREASE IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE GREAT LAKES. THE INCREASING CLOUDS SHOULD KEEP TEMPERATURES FROM BOTTOMING OUT AS LOW AS SOME WHAT SOME OF THE GUIDANCE IS INDICATING BUT NEVERTHELESS, EXPECT LOWS TO BE GENERALLY IN THE TEENS. AS THE SYSTEM CONTINUES TO ADVANCE EASTWARD WEDNESDAY THE CHANCES FOR LIGHT PRECIPITATION IN THE FORM OF MIXED RAIN/SNOW WILL DEVELOP FROM WEST TO EAST THROUGH THE DAY. THE FORECAST BECOMES A BIT TRICKY FOR WEDNESDAY NIGHT INTO THURSDAY. THE GEM GLOBAL AND THE NAM TRACK THE SYSTEM EAST GIVING MOST OF THE AREA A CONTINUING PERIOD OF GENERALLY LIGHT PRECIPITATION WHILE THE GFS AND THE EURO ARE QUICKER TO SHUNT THE SYSTEM OFF TO THE SOUTH AND EAST IN RESPONSE TO THE CIRCULATION AROUND AN UPPER LEVEL LOW OVER ATLANTIC CANADA. AT THIS POINT OPTED TO PLAY THE MIDDLE GROUND AND BRING CHANCE POPS TO ALL BUT EXTREME NORTHERN AND EASTERN AREAS DURING THIS PERIOD AND HOLDING POPS JUST BELOW THE LIKELY RANGE OVER THE SOUTH AND WEST. NORTHERLY WINDS COMBINED WITH THE DIURNAL CYCLE WILL ALLOW FOR ANY MIXED PRECIP OR RAIN TO CHANGE TO ALL SNOW WEDNESDAY NIGHT WITH SOME MIXING LIKELY ONCE AGAIN FOR THURSDAY. THE SYSTEM LOOKS TO BE MAINLY SOUTH AND EAST OF THE REGION BY LATE DAY THURSDAY. THERE IS THE POTENTIAL FOR SOME SNOW ACCUMULATION TO HAVE OCCURRED BY THIS TIME MAINLY OVER WESTERN SECTIONS ALTHOUGH AT THIS POINT ANY AMOUNTS DO NOT LOOK LIKELY TO BE SIGNIFICANT DUE TO THE RELATIVELY MILD TEMPERATURES AND GENERALLY LIGHT NATURE OF THE PRECIP. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE REGION THURSDAY NIGHT. A DRIER NW FLOW WILL FOLLOW FOR THURSDAY NIGHT AND FRIDAY WITH CLEARING SKIES EXPECTED THURSDAY NIGHT AND MOSTLY SUNNY SKIES FRIDAY. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE REGION FRIDAY NIGHT THROUGH SATURDAY WITH CONTINUED DRY WEATHER. LOW PRESSURE WILL PASS TO OUR SOUTH SATURDAY NIGHT AND SUNDAY SO EXPECT MAINLY DRY WEATHER THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE WILL BUILD BACK ACROSS THE REGION ON MONDAY. TEMPERATURES WILL BE NEAR OR A BIT ABOVE NORMAL FOR THIS TIME OF YEAR THROUGH THE PERIOD. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... NEAR TERM: VFR WITH A PD OF MVFR CLGS IN BKN-OVC TNGT AT KFVE AND POSSIBLE AT KCAR AND KPQI. SHORT TERM: EXPECT VFR CONDITIONS THROUGH TUESDAY NIGHT. MVFR/IFR CONDITIONS WILL BE POSSIBLE BY LATE DAY WEDNESDAY INTO THURSDAY, ESPECIALLY SOUTH, DUE TO THE NEXT SYSTEM BRINGING THE CHANCE FOR SNOW/RAIN AND LOW CLOUDS. && .MARINE... NEAR TERM: WILL CONT THE GLW OVR ALL OF OUR WATERS THRU MOST OF TUE AFTN AS ADVERTISED OVR THE PAST DAY OR SO. ONCE IT RUNS OUT... AN SCA WILL BE NEEDED FOR ALL OF WATERS VERY LATE TUE AFTN INTO TUE EVE. WENT WITH AN EVEN BLEND 12Z GFS/NAM/GMOS FOR WINDS AND A 40%/30%/30% WW3/SWAN-GFS/SWAN NAM BLEND FOR WV HTS...WHICH RAISE WV HTS BY WW3 ALONE AN XTRA FOOT TO FOOT AND A HALF OVR OUTER MOST WATERS. SHORT TERM: WINDS AND WAVES WILL DIMINISH THROUGH TUESDAY NIGHT AND WILL BE BELOW SCA LEVELS BY WEDNESDAY MORNING. HOWEVER THE NEXT SYSTEM WILL BRING THE CHANCE FOR RAIN/SNOW BY LATE DAY WEDNESDAY CONTINUING INTO THURSDAY AND WILL ALSO BRING THE POTENTIAL FOR SCA CONDITIONS ALONG WITH REDUCED VISIBILITIES. && .FIRE WEATHER... AFTER COORDINATING WITH THE ST OF ME FOREST SERVICE...WE OPTD TO ISSUE A FIRE WX WATCH FOR ZONES 5...6 SWRD TO THE COAST. AREAS N AND W OF THE WATCH AREA HAVE FINE FUELS DEEMED TO WET TO BE ABLE TO DRY OUT FOR POSSIBLE IGNITION. WITHIN THE WATCH AREA... FINE FUELS HAVE BEEN DAMPENED FROM RELATIVELY LGT QPF FROM YSDY`S PRECIP EVENT...BUT VERY STRONG WINDS AND LOW MIDDAY AND AFTN RH`S COULD DRY OUT FUELS TO HIGH DANGER RATING CATEGORY. GIVEN UNCERTAINTY OF DRYING POTENTIAL BETWEEN NOW AND MIDDAY TUE...IT`S A TOSS UP WHETHER THE WATCH WILL BE UPGRADED TO A RED FLG WRNG FOR ALL OR PARTS OF THE WATCH AREA MIDDAY TIL ERLY EVE TUE OR TO AN SPS HIGHLIGHTING NO BURNING OF REFUGE DURG THIS TM. A DECISION WILL BE MADE REGARDING THESE OPTIONS LATE TUE MORN. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WIND ADVISORY FROM 7 AM TO 7 PM EDT TUESDAY FOR MEZ001>006-010- 011-015>017-029>032. FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR MEZ005-006-011-015>017-029>032. MARINE...GALE WARNING UNTIL 5 PM EDT TUESDAY FOR ANZ050>052. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
401 AM EDT MON MAR 26 2012 .SYNOPSIS... CANADIAN HIGH PRESSURE WILL PROVIDE COLD, DRY, NORTHERLY WINDS ACROSS THE UPPER OHIO VALLEY TODAY. A HARD FREEZE WILL BE THE RESULT TONIGHT. A SOUTHEAST BOUND CANADIAN LOW WILL BRING MILD SHOWERY CONDITIONS WEDNESDAY, FOLLOWED BY DRY, SEASONABLE CONDITIONS INTO THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST HIRES MODELS CONTINUE TO SHOW AND AREA OF STRATOCU DEVELOPING AHEAD OF STRONG CAA THIS MORNING. CURRENT SAT PICS ARE SHOWING THIS AREA OF LOWER CLOUDS MOVING SOUTHWARD FROM THE GREAT LAKES, EXPECT A PERIOD OF CLOUDS TO BLANKET THE AREA THROUGH MID- MORNING. THESE CLOUDS WILL DISSIPATE QUICKLY AS A MUCH DRIER AIR MASS MOVES IN. BY LATE THIS MORNING AND EARLY AFTERNOON, EXPECT MAINLY SUNNY SKIES. COLD NORTHWEST WINDS EMANATING FROM EASTBOUND CANADIAN HIGH PRESSURE WILL LOWER 850 MB TEMPERATURES TO -7C. HENCE CONCUR WITH NAM AND GFS MOS THAT AFTERNOON TEMPERATURES WILL BE COLDER THAN CURRENT READINGS. NAM MODEL PROFILES SHOW NORTHWEST WINDS CAN GUST TO 25 MPH THIS AFTERNOON. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... MONDAY NIGHT WILL BE THE PERIOD OF COLDEST TEMPS WITH MODELS IN VERY GOOD AGREEMENT THAT OVERNIGHT LOWS WILL FALL INTO THE 20S. TEMPERATURES COLDER THAN 24F CONSTITUTE A HARD FREEZE WHICH GFS AND NAM MOS HAVE BEEN SHOWING. HENCE HAVE UPGRADED THE FREEZE WATCH TO A FREEZE WARNING. BECAUSE THIS IS SUCH A RARE CONGLOMERATION OF EVENTS, FELT IT NECESSARY TO ISSUE THE WARNING FOR ALL COUNTIES. AS WINDS ABATE TUESDAY, SUNSHINE SHOULD HELP TEMPERATURES REBOUND TO SEASONABLE LEVELS TUESDAY AFTERNOON. A WEAK COLD FRONTAL PASSAGE WEDNESDAY WILL BRING CLOUDINESS AND A CHANCE OF SHOWERS BUT WITH TEMPERATURES WELL ABOVE NORMAL. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL FOLLOW THURSDAY WITH DRY WEATHER BUT COOLER TEMPERATURES. HIGH PRESSURE WILL DOMINATE INTO THE WEEKEND WITH DRY WEATHER AND SLOWLY MODERATING TEMPERATURES. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... RECENT SURFACE AND SATELLITE DATA SHOW MVFR STRATUS LINGERING NEAR THE MOUNTAINS WHILE A NEW BATCH HAS BEGUN TO DEVELOP BETWEEN KPIT-KCLE. HRRR AND NAM MODEL OUTPUT SHOW ADDITIONAL MVFR STRATUS DEVELOPING ACROSS MUCH OF THE UPPER OHIO VALLEY 09Z-14Z, AS THE SURFACE LAYER COOLS AND SATURATES DUE TO ADVECTIVE AND NOCTURNAL COOLING. NAM MODEL PROFILES AND GFS LAMP THEN SHOW THE LOW CLOUDS DISSIPATING TO PROVIDE CLEAR SKIES BY 16Z. SKIES WILL REMAIN CLEAR TONIGHT, AND EXPECT NO MORE THAN CIRRUS DAYTIME TUESDAY. SURFACE WINDS WILL BE FROM THE NORTHWEST INCREASING TODAY TO 13 KTS WITH GUSTS 20 TO 25 KTS BY AFTERNOON. WINDS WILL DECREASE TO 5-10 KTS TONIGHT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 10 PM THIS EVENING TO 10 AM EDT TUESDAY FOR MDZ001. OH...FREEZE WARNING FROM 10 PM THIS EVENING TO 10 AM EDT TUESDAY FOR OHZ039>041-048>050-057>059-068-069. PA...FREEZE WARNING FROM 10 PM THIS EVENING TO 10 AM EDT TUESDAY FOR PAZ007>009-013>016-020>023-029-031-073>076. WV...FREEZE WARNING FROM 10 PM THIS EVENING TO 10 AM EDT TUESDAY FOR WVZ001>004-012-021>023-041. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
224 AM EDT MON MAR 26 2012 .SYNOPSIS... CANADIAN HIGH PRESSURE WILL PROVIDE COLD DRY NORTHERLY WINDS ACROSS THE UPPER OHIO VALLEY TODAY, THAT WILL RESULT IN A HARD FREEZE TONIGHT. A SOUTHEASTBOUND CANADIAN LOW PRESSURE SYSTEM WILL BRING MILD SHOWERY CONDITIONS WEDNESDAY FOLLOWED BY DRY SEASONABLE CONDITIONS INTO THE WEEKEND. && .NEAR TERM /THROUGH TODAY/... PER RECENT SATELLITE DATA AND HRRR AND NAM MODEL OUTPUT THERE CAN BE A PERIOD OF LOW CLOUDS THIS MORNING. OTHERWISE SKIES WILL BE MAINLY CLEAR TODAY. COLD NORTHWEST WINDS EMANATING FROM EASTBOUND CANADIAN HIGH PRESSURE WILL LOWER 850 MB TEMPERATURES TO 7C. HENCE CONCUR WITH NAM AND GFS MOS THAT AFTERNOON TEMPERATURES WILL BE COLDER THAN CURRENT READINGS. NAM MODEL PROFILES SHOW NORTHWEST WINDS CAN GUST TO 25 MPH THIS AFTERNOON. && .SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/... MONDAY NIGHT WILL BE THE PERIOD OF COLDEST TEMPS WITH MODELS IN VERY GOOD AGREEMENT THAT OVERNIGHT LOWS WILL FALL INTO THE 20S. TEMPERATURES COLDER THAN 24F CONSTITUTE A HARD FREEZE WHICH GFS AND NAM MOS HAVE BEEN SHOWING. HENCE HAVE MAINTAINED A FREEZE WATCH. WILL LIKELY BE ISSUING A FREEZE WARNING WITH 4 AM ISSUANCE. AS WINDS ABATE TUESDAY, SUNSHINE SHOULD HELP TEMPERATURES REBOUND TO SEASONABLE LEVELS TUESDAY AFTERNOON. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... A WEAK COLD FRONTAL PASSAGE WEDNESDAY WILL BRING CLOUDINESS AND A CHANCE OF SHOWERS BUT WITH TEMPERATURES WELL ABOVE NORMAL. HIGH PRESSURE WILL FOLLOW THURSDAY WITH DRY WEATHER BUT COOLER TEMPERATURES. HIGH PRESSURE WILL DOMINATE INTO THE WEEKEND WITH DRY WEATHER AND SLOWLY MODERATING TEMPERATURES. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... RECENT SURFACE AND SATELLITE DATA SHOW MVFR STRATUS LINGERING NEAR THE MOUNTAINS WHILE A NEW BATCH HAS BEGUN TO DEVELOP BETWEEN KPIT-KCLE. HRRR AND NAM MODEL OUTPUT SHOW ADDITIONAL MVFR STRATUS DEVELOPING ACROSS MUCH OF THE UPPER OHIO VALLEY 09Z-14Z, AS THE SURFACE LAYER COOLS AND SATURATES DUE TO ADVECTIVE AND NOCTURNAL COOLING. NAM MODEL PROFILES AND GFS LAMP THEN SHOW THE LOW CLOUDS DISSIPATING TO PROVIDE CLEAR SKIES BY 16Z. SKIES WILL REMAIN CLEAR TONIGHT, AND EXPECT NO MORE THAN CIRRUS DAYTIME TUESDAY. SURFACE WINDS WILL BE FROM THE NORTHWEST INCREASING TODAY TO 13 KTS WITH GUSTS 20 TO 25 KTS BY AFTERNOON. WINDS WILL DECREASE TO 5-10 KTS TONIGHT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...FREEZE WATCH FROM THIS EVENING THROUGH TUESDAY MORNING FOR OHZ039>041-048>050-057>059-068-069. PA...FREEZE WATCH FROM THIS EVENING THROUGH TUESDAY MORNING FOR PAZ007>009-013>016-020>023-029-031-073-075. WV...FREEZE WATCH FROM THIS EVENING THROUGH TUESDAY MORNING FOR WVZ001>004-012-021-022. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
843 PM EDT TUE MAR 27 2012 .SYNOPSIS... ISSUED AT 408 PM EDT TUE MAR 27 2012 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW POTENT NEGATIVELY TILTED SHRTWV/STACKED LO MOVING ENEWD THRU NRN MN ON TOP OF MEAN RDG OVER THE SE CONUS. PCPN/WARM CONVEYOR BELT WELL E OF THE LO HAS MOVED E OF THE CWA...BUT LO CLDS LINGER IN THE RELATIVELY MOIST LYR ASSOCIATED WITH SHARP WAD INVRN DEPICTED ON THE 12Z RAOBS. SKIES ARE MOCLR OVER MN UNDER THE DRY SLOT/JET SURGE REGION OF THE LO...AND TEMPS HAVE RISEN WELL INTO THE 50S AND 60S IN THAT AREA. DESPITE THIS SHARP WAD STABILITY...GUSTY S WINDS UP TO 50 MPH UNDER SHARP PRES GRADIENT BTWN THE LO AND RETREATING HI PRES OVER SE ONTARIO HAVE IMPACTED LOCATIONS NEAR THE LK SUP SHORE...PROMPTING ISSUANCE OF WIND ADVY. IN FACT...THE 12Z MPX RAOB INDICATED A WIND SPEED OF 61KTS AT 3K FT AGL WITHIN THE STABLE INVRN LYR. THE S WIND OFF THE RELATIVELY CHILLY LK MI WATERS HAVE ENHANCED THE LLVL STABILITY AND PREVENTED THE WINDS IN THAT AREA FM BEING AS STRONG AS NEAR LK SUP. FARTHER TO THE W...DEEP WRAP ARND MSTR SHOWN ON THE 12Z BISMARCK RAOB IS MOVING INTO NW NW IN THE WAKE OF THE DEPARTING LO. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 408 PM EDT TUE MAR 27 2012 MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON WINDS/CLD TRENDS AND PSBL WRAP ARND -SHRA AS MN LO MOVES ACRS NRN LK SUP AND INTO SE ONTARIO ON WED. TNGT...SHRTWV/CLOSED LO IN MN ARE PROGGED TO MOVE INTO SE ONTARIO JUST NE OF THE SAULT BY 12Z WED. AS THE PRES GRADIENT WEAKENS AT LEAST TEMPORARILY WITH THE APRCH OF THE SFC LO...EXPECT WINDS TO DIMINISH LATE THIS AFTN/EARLY EVNG. SO WL LET THE GOING WIND ADVY EXPIRE AT 21Z AS SCHEDULED. ALTHOUGH THE EARLY EVNG WL BE PCPN FREE FOR THE MOST PART UNDER DRY SLOT...MORE CLDS/SCT -SHRA WL ARRIVE FM THE W AS THE WRAP ARND MSTR ACCOMPANYING THE EWARD MOVING LO PRES SLIDES INTO THE UPR LKS. STRONG W H925 WINDS UP TO 40-50 KTS ON THE WRN FLANK OF THE LO WL ADVECT MUCH COOLER AIR INTO THE AREA...WITH H85 TEMPS FCST AS LO AS -2C OR -3C OVER THE W BY 12Z...BUT FCST WBLB ZERO HGT WELL ABV 1K FT SUGS THE PCPN WL REMAIN MAINLY IN THE FORM OF RA EXCEPT OVER THE HIER TERRAIN OF THE W LATE. EXPECT STRONG W WINDS TO IMPACT THE W LATE AS WELL...WITH WIND GUSTS APRCHG ADVY LVL AGAIN OVER THE FAR W S OF CMX WHERE THE CORE OF STRONGEST WINDS COINCIDES WITH THE INCOMING H85 THERMAL TROF. CONSIDERED EXTENDING WIND ADVY FOR THE KEWEENAW...BUT AXIS OF STRONGER WINDS POINTING TOWARD THIS EXPOSED AREA DOES NOT COINCIDE WITH THERMAL TROFFING/ REDUCED STABILITY THAT WOULD ENHANCE MIXING. WED...AS THE CLOSED LO TO THE E MOVES FARTHER AWAY...SFC HI PRES RDG WL BLD INTO THE AREA UNDER RISING H5 AHEAD OF PROGRESSIVE UPR RDG IN THE PLAINS. MRNG -SHRA...MIXED WITH SN PER LOWER WBLB ZERO HGTS AS H85 TEMPS FALL TO ARND -5C...MAINLY IN THE UPSLOPE AREAS OVER THE NRN TIER WL DIMINISH WITH TIME UNDER NEGATIVE DYNAMICS/MID LVL DRYING AND GRDLY MORE ACYC FLOW... BUT FCST SDNGS SUG PLENTY OF LO CLD WL LINGER...SO TENDED TOWARD THE LOWER END OF GUIDANCE FOR TEMPS. AS THE LO MOVES AWAY AND HI PRES MOVES TOWARD THE AREA...THE WINDS WL DIMINISH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 408 PM EDT TUE MAR 27 2012 WED NIGHT...H925 TEMPS AROUND -6C WILL LEAD TO ENOUGH LK INSTABILITY TO KEEP CLOUDS GOING THROUGH MUCH OF THE NIGHT FOR LOCATIONS FAVORED BY VEERING N TO NE WINDS NEAR LK SUPERIOR. LINGERED SLIGHT CHANCES THROUGH THE EVENING FOR THE NRLY FAVORED LOCATIONS BEFORE DIMINISHING IT OVERNIGHT. DID HOLD ON TO THE SLIGHTS LONGER FOR THE UPSLOPE LOCATIONS IN NCNTRL UPPER MI...ALTHOUGH THE LOWERING INVERSION WILL LIMIT CLOUD DEPTH. THURS SHOULD BE A SIMILAR DAY TO YESTERDAY WITH HUDSON BAY HIGH PRESSURE RIDGE OVER UPPER MI. NE WINDS WILL PULL DRIER AIR INTO UPPER MI AND LEAD TO A MOSTLY SUNNY DAY OVER THE EAST HALF. FARTHER WEST...MID CLOUDS WILL BE WORKING OVER THE AREA THROUGH THE AFTERNOON...ALONG WITH SOME SHOWERS OVER WRN LK SUPERIOR...AHEAD OF THE APPROACHING SHORTWAVE. HIGHS WILL BE WARMEST INTERIOR AWAY FROM THE LK SUPERIOR INFLUENCE...WHICH WILL ALLOW FOR DEEPER MIXING AND HIGHS RISING INTO THE MID-UPPER 40S. OTHERWISE...LOCATIONS NEAR LAKE SUPERIOR WILL BE IN THE UPPER 30S AND LOWER 40S. DEWPOINTS ARE THE MAIN ADJUSTMENT TO THE FORECAST...AS MODELS ARE COMING INTO BETTER AGREEMENT WITH ML DEWPOINTS FALLING INTO THE SINGLE DIGITS ABOVE ZERO OVER THE ERN CWA. WILL DROP TD VALUES AGAIN SEVERAL DEGREES OVER THE ERN CWA INTO THE UPPER TEENS. MAY NEED TO DROP THEM EVEN MORE...SINCE MIXED LAYER DEWPOINTS VERIFIED FAIRLY WELL YESTERDAY. THURS NIGHT...CLEAR INITIALLY AND WITH THE LIGHT WINDS OVER THE ERN CWA...SHOULD SEE A QUICK FALL IN TEMPS DURING THE EVENING HOURS. BUT INCREASING CLOUDS AHEAD OF THE APPROACHING SHORTWAVE WILL CAUSE THE TEMPS TO RISE THROUGH THE NIGHT. TRIED TO SHOW A QUICK DROP IN THE EVENING...BUT UNSURE THE AMOUNT OF WARMING WITH LIMITED WINDS AND MAINLY MID-HIGH CLOUDS...SO HAVE HELD THEM STEADY. SHOWERS ENTERING THE WRN HALF OF THE CWA DURING THE OVERNIGHT HOURS. ASSOCIATED WITH H850-700 WAA IN THE EVENING...WHICH THEN FOCUSES FARTHER S THROUGH THE OVERNIGHT HOURS. THIS SHOULD DIMINISH THE COVERAGE OF THE SHOWERS AS THEY PUSH E. PTYPE IS TRICKY SINCE IT WILL BE FALLING AS SNOW...BUT THEN AN ISOTHERMAL LAYER AT 0C LOOKS TO SETUP FROM 2-6KFT BEFORE NEAR SFC TEMPS BELOW 2KFT WILL BE ABOVE FREEZING. THIS CREATES A SNOW/RAIN MIX SCENARIO AND SMALL DIFFERENCES IN THE THERMAL PROFILE WILL DETERMINE PCPN TYPE. THUS...WENT WITH A RAIN/SNOW MIX OVER UPPER MI...WITH BETTER SNOW CHANCES TO THE NE HALF. FRI...MODELS BECOMING MORE CONSISTENT ON THE BULK OF THE PCPN GOING S OF THE CWA WITH THE SHORTWAVE WEAKENING AS IT TRIES TO PUSH THROUGH THE UPPER RIDGE AND FOCUSING OF THE BETTER H850-700 WAA FARTHER SE OVER LK MI AND LOWER MI. THEREFORE...HAVE A DIMINISHING TREND OVER THE ERN CWA THROUGH THE DAY DUE TO THE PERSISTENT LLVL DRY AIR FROM THE HUDSON BAY HIGH. SHOULD BE A MIX OF RAIN/SNOW IN THE MORNING BEFORE DAYTIME HEATING WOULD CHANGE ANY LINGERING PCPN TO RAIN. EXTENDED /FRIDAY NIGHT THROUGH TUESDAY/... HPC FOLLOWED A 00Z GFS/ECMWF ENS MEAN FOR DAYS 5-7...SINCE THERE IS DECENT CONSISTENCY IN THE TROUGH MOVING OUT OF THE WRN CONUS DURING THAT TIMEFRAME. ANOTHER SHORTWAVE MOVES THROUGH THE UPPER GREAT LKS FOR FRI NIGHT INTO SAT. MOISTURE IS FAIRLY LIMITED...ALONG WITH H850-700 Q-VECTOR CONV...SO THINK OVERALL PCPN CHANCES WILL BE LIMITED. UPPER RIDGE BUILDS OVER THE AREA ON SAT NIGHT INTO SUN NIGHT IN RESPONSE TO UPPER TROUGH OVER THE WRN CONUS SHIFTING INTO THE PLAINS STATES. DETERMINISTIC RUNS STILL DIFFERING IN THE INTENSITY/AMPLITUDE OF THIS TROUGH...WITH THE 00Z GFS MUCH DEEPER AND THE 00Z ECMWF BROADER AND OVER THE CNTRL/NRN PLAINS. 12Z GFS HAS TRENDED TOWARDS THE 00Z ECMWF AND WILL FOLLOW THE HPC SOLN AND HAVE THE BROAD SFC LOW OVER THE CNTRL/NRN PLAINS ON SUN SLIDING SE THROUGH THE UPPER MISS VALLEY AND LOWER GREAT LKS THROUGH TUES. BEFORE THAT...WARM FRONT LOOKS TO SETUP SOMEWHERE OVER THE UPPER GREAT LKS OR SRN ONTARIO...WHICH WOULD HAVE A LARGE AFFECT ON HIGHS. DIFFERENCES IN MODEL SOLNS GIVE UNCERTAINTY IN TEMPS FOR SUN...AS H850 TEMPS RANGE FROM 7-14C. MAY NOT MIX QUITE THAT HIGH...BUT MIXING TO H900 WOULD STILL YIELD HIGHS IN THE 60S. SO HAVE BUMPED UP THE EXISTING FORECAST A FEW DEGREES. HEADING INTO SUN NIGHT THROUGH TUES...AREA WILL BE ON THE NRN FRINGES OF THE SFC LOW FEATURES. IF THE LOW TRENDS TOWARDS THE 00Z GFS...WILL LIKELY BE DRY...BUT IF THE 00Z ECMWF AND 12Z GFS ARE CORRECT WE/LL HAVE BETTER SHOT OF SEEING PCPN. DON/T SEE ANY REASON TO GO ANYTHING MORE THAN LOW END CHANCES AND WILL KEEP THE PCPN AS RAIN WITH THE ABUNDANT WARM AIR REMAINING OVER THE AREA. AS THIS UPPER TROUGH SHIFTS E FOR THE END OF THE WEEK...COULD SEE A TRANSITION TO A BELOW NORMAL TEMPERATURE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 843 PM EDT TUE MAR 27 2012 STRONG WEST WINDS IN THE WAKE OF A SFC TROUGH/COLD FRONT WILL KICK IN LATER THIS EVENING AT KIWD AND KCMX WITH WITH GUSTS OF 30 TO 35KTS EXPECTED THROUGH TONIGHT...ESPECIALLY AT KCMX. WITH COLDER AIR MOVING IN BEHIND THE FRONT...LOW CLOUDS IN THE MVFR TO OCCASIONAL IFR RANGE ALONG WITH LAKE EFFECT RAIN SHOWERS WILL ALSO MOVE INTO KIWD AND KCMX. IT MAY GET COLD ENOUGH AT KIWD FOR SOME SNOW TO MIX IN WITH THE RAIN LATE TONIGHT AND WED MORNING. MVFR CLOUD DECK WILL ALSO MOVE INTO KSAW LATE TONIGHT BUT RAIN SHOWERS SHOULD HOLD OFF UNTIL AFT 12Z WED WHEN WINDS VEER NW. WINDS WILL DIMINISH AND CIGS SHOULD IMPROVE...ESPECIALLY FM THE WEST LATE WED AS A HIGH PRESSURE RIDGE BUILDS IN FROM NRN ONTARIO. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 408 PM EDT TUE MAR 27 2012 ALTHOUGH THE GOING S GALES OVER THE E HALF OF LK SUP WILL DIMINISH BY EARLY THIS EVENING AS LO PRES IN MN/WEAKER PRES GRADIENT ARRIVE...A STRONGER W TO NW WIND WILL REDEVELOP LATER TONIGHT AS THE LO MOVES TO THE E ACROSS LAKE SUP...WITH MORE GALE FORCE WINDS OVER MAINLY THE W AND NCENTRAL AT TIMES INTO WED MORNING WHEN THE ARRIVAL OF COLDER AIR AS WELL WILL RESULT IN ENHANCED MIXING. THE APPROACH OF A HI PRES RIDGE AND WEAKER PRES GRADIENT WILL RESULT IN DIMINISHING WINDS BY WED AFTERNOON. HIGH PRESSURE RIDGE OVER THE AREA ON WED NIGHT WILL LEAD TO DIMINISHING WINDS AS THEY BACK TO THE NE. EXPECT WINDS TO STAY BELOW 20KTS FOR MUCH OF THE PERIOD AS A SERIES OF WEAK DISTURBANCES AND HIGH PRESSURE RIDGES MOVE ACROSS THE AREA THROUGH THE WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 AM EDT WEDNESDAY FOR LSZ266. GALE WARNING FROM 5 AM TO 11 AM EDT WEDNESDAY FOR LSZ244-245-264. GALE WARNING UNTIL 5 AM EDT /4 AM CDT/ WEDNESDAY FOR LSZ241-242- 263. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...KC SHORT TERM...KC LONG TERM...SRF AVIATION...VOSS MARINE...KC/SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 PM EDT MON MAR 26 2012 .SYNOPSIS... ISSUED AT 417 PM EDT MON MAR 26 2012 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SPRAWLING UPR RDG OVER CNTRL NAMERICA BTWN TROFS OVER QUEBEC/NEW ENGLAND AND ANOTHER OFF THE W COAST. HUDSON BAY HI PRES UNDER THE CONFLUENT NW FLOW ALF BTWN THE RDG AND ERN TROF AS WELL AS VERY DRY AIRMASS DEPICTED ON THE 12Z INL AND GRB RAOBS /12Z H85 DEWPT DEPRESSION WAS 43C AT INL/ ARE BRINGING A TRANQUIL BUT MORE SEASONABLY CHILLY DAY TO UPR MI. BUT MORE CLDS WELL IN ADVANCE OF SHARP WARM FNT ATTENDANT TO DVLPG LO PRES IN THE NW HI PLAINS ARE SPREADING FM MN/NW WI TOWARD IWD. THIS SFC LO IS ASSOCIATED WITH VIGOROUS NEGATIVELY TILTED SHRTWV LIFTING NEWD OUT OF THE DESERT SW. THE WARM FNT SEPARATES VERY WARM AIRMASS IN THE SRN PLAINS WITH 12Z H85 TEMP AS HI AS 20C AT DODGE CITY KS FM CHILLY AIRMASS IN THE GRT LKS/H85 TEMPS OF -8C AT YPL AND APX. SOME -SHRASN ARE FALLING OVER PARTS OF MN/NW WI UNDER THE THICKER CLDS/ SHARPER H85-7 FGEN AS 12Z MPX RAOB SHOWS A SATURATED LYR FM H85-5. THERE HAVE BEEN A FEW LTG STRIKES UNDER THIS BAND OF SHRA TODAY. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 417 PM EDT MON MAR 26 2012 MAIN FCST CONCERNS TNGT INTO TUE ARE MIXED PCPN/ICING POTENTIAL/ GOING FZRA ADVY ASSOCIATED WITH APRCHG WARM FNT...THEN SHRA CHCS ON TUE WITH ARRIVAL OF DRY SLOT. TNGT...AS HI PRES/COLD DRY AIRMASS IN ONTARIO THIS AFTN RETREAT INTO QUEBEC AND SHRTWV IN THE DESERT SW SHIFTS NEWD INTO THE NRN PLAINS TNGT IN RATHER PROGRESSIVE UPR FLOW...ATTENDANT WARM FNT/CLD BAND TO THE SW WL CLOSE IN ON UPR MI. THE COMBINATION OF VIGOROUS ISENTROPIC ASCENT/MID LVL MOISTENING ACCOMPANYING STRENGHTENING SSW FLOW/H925 WINDS INCRSG TO 50KTS...INCRSG H4-2 DVGC...AND H85-7 FGEN WL ALLOW FOR PCPN TO BREAK OUT W-E TOWARD ERY ARND 12Z DESPITE LINGERING LLVL DRY AIR. SINCE THE MID LVLS MOISTEN AND DYNAMICS ARRIVE BEFORE THE LLVLS WARM/MOISTEN...FCST SDNGS INDICATE A GOOD POTENTIAL FOR FZRA/SLEET WITH WBLB TEMPS AS LO AS -5C TO -7C IN THE SUB H85 LYR UNDER THE FGEN PCPN BAND. USED A NON DIURNAL TOOL FOR TEMPS WITH MIN READINGS RELATIVELY EARLY...THEN TEMPS RISING LATER WITH INCRSG WIND/WAD. EVAPORATE COOLING NEAR THE SFC WL TEND TO SLOW THE RISE IN AREAS EXPERIENCING PCPN. INCLUDED MENTION OF TS W OF THE AXIS OF MAX FGEN WITH H8-5 LAPSE RATES NEAR MOIST ADIABATIC ENHANCED BY THE WAD/VIGOROUS DYNAMICS. TUE...SHRTWV/OCCLUDED LO ARE FCST TO MOVE TO JUST NW OF THUNDER BAY ONTARIO BY 00Z WED...WITH ACCOMPANYING DRY SLOT ON ITS SE FLANK IMPACTING THE CWA. AFT AREA OF DEEPER MSTR/WAD/H85-7 FGEN/H4-2 DVGC EXIT THE E BY 18Z...ANY LINGERING PCPN SHOULD BE NOTHING MORE THAN ISOLD/SCT -SHRA AS FCST SDNGS SHOW QUITE A BIT OF MID LVL DRYING/ CAPPING DVLPG AFT THE EXIT OF THE DEEPER MSTR/DYNAMICS. GUSTY WINDS WL DVLP WITH LLVL WARMING/DESTABILIZATION MIXING OUT THE HIER MOMENTUM ABV INITIAL SHARP INVRN. BEST CHC FOR CLRG WL BE OVER THE FAR W FM IWD-ONTONAGON WITH DOWNSLOPING S WIND. MIXING TO H85 ON NAM/GFS FCST SDNGS INDICATE MAX TEMPS MAY REACH 60 IN THIS AREA. LOCATIONS DOWNWIND OF LK MI WL BE MUCH COOLER WITH FLOW OFF CHILLY WATERS MAINTAINING HIER STABILITY/TEMPS TOWARD THE LOWER END OF GUIDANCE. AS FOR HEADLINES...SUSPECT MODEL QPF THAT WOULD INDICATE NEED FOR AN ICE STORM WARNING IS A BIT TOO HI CONSIDERING THE STEADY EWD MOVEMENT FCST OF THE FGEN/UPR DVGC CORE AND LINGERING LLVL DRY AIR...SO ADVY SHOULD COVER THE FRZG PCPN POTENTIAL WITH ANY ICE ACCUMULATION NOT LIKELY TO EXCEED ABOUT 0.10 INCH. RECENT WARM SOILS ALSO WL TEND TO LIMIT ICE ACCUM POTENTIAL. TWEAKED THE TIMING OF THE HEADLINE A BIT TO ACCOUNT FOR SLOWER ARRIVAL OF PCPN INTO THE CENTRAL COUNTIES. ALSO EXPANDED THE FZRA HEADLINE TO THE E EXCEPT FOR MNM COUNTY...WHICH WL BE FARTHEST S OF THE SHARPER DYNAMICS AND PROBABLY SEE LESS PCPN/ICING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 417 PM EDT MON MAR 26 2012 995MB LOW LOCATED OVER THE ARROWHEAD OF MN AT 00Z AND WILL SLIDE E ACROSS LK SUPERIOR ON TUES NIGHT. BULK OF INITIAL PCPN WILL HAVE EXITED THE CWA AT THE START OF THE LONG TERM PERIOD. MAIN AREA OF PCPN THROUGH THE NIGHT WILL BE LOCATED ALONG THE WARM FRONT OVER NE LK SUPERIOR...BUT WRAP AROUND SHOWERS WILL AFFECT THE NRN HALF OF UPPER MI THROUGH A GOOD PORTION OF THE NIGHT. EXPECT THE PCPN TO FALL AS RAIN...DUE TO THE LOW LLVL WARM AIR SURGING N THROUGH THE NIGHT AHEAD OF THE COLD FRONT. AS COLD AIR ARRIVES OVER THE WEST COULD SEE THE RAIN MIXING WITH SNOW OVER THE FAR WEST NEAR DAYBREAK. WITH THE LLVL WARM AIR AHEAD OF THE FRONT...FOLLOWED A NON-DIURNAL TEMP CURVE ON TUES NIGHT. TEMPS WILL BE WARMER OVER PORTIONS OF THE CENTRAL/ERN CWA TUESDAY NIGHT THAN DURING THE DAY TUESDAY...VALUES REACHING THE MID-UPPER 40S. COLD FRONT WILL SLIDE THROUGH THE AREA ON WED MORNING AND LEAD TO FALLING H850 TEMPS AND WINDS SHIFTING TO THE NNW. WITH H850 TEMPS FALLING FROM 1-2C AT 12Z WED TO -4 TO -6C BY 00Z THURS SHOULD SEE LK ENHANCED SHOWERS THROUGH A GOOD PORTION OF THE DAY...ESPECIALLY WITH THE DEEPER MOISTURE PRESENT DURING THE MORNING HOURS. HAVE PEAKED THE POPS OVER THE WEST DURING THAT TIME FRAME...THEN DIMINISHED THROUGH THE DAY AS DRY AIR STARTS TO ERRODE THE PCPN FROM THE NW. PCPN TYPE IS THE MAIN CONCERN FOR WED. NAM SHOWING CLOUD TOP IS AROUND -8 TO -10C SO PCPN START AS SNOW IN THE CLOUDS...BUT GFS IS WARMER WITH CLOUD TOP TEMPS AROUND -5C AND MAINLY RAIN. HAVE FOLLOWED A LITTLE COOLER TEMPERATURES AND A THE PCPN STARTING AT SNOW. THE LLVL WARM LAYER WILL BE THE MAIN PCPN TYPE FACTOR...AS IT WILL TRY TO MELT THE PCPN BEFORE IT HITS THE SFC. USED A COMBINATION OF SFC TEMPS AND WETBULB ZERO HEIGHTS FOR RAIN/SNOW POTENTIAL ON WED...WITH THE HIGHER TERRAIN SEEING THE SNOW FIRST AND THEN SPREADING ACROSS THE AREA FROM N TO S THROUGH THE AFTN AND EARLY EVENING BUT OVERALL PCPN SHOULD BE DIMINISHING THEN. NON DIURNAL TEMP CURVE AGAIN ON WED...HIGHS IN THE MORNING AND EARLY AFTN THEN FALLING. LK ENHANCED SHOWERS WILL BE DIMINISHING FROM W TO E IN THE AFTN/EVENING...AS DRIER AIR AND ANTICYCLONIC FLOW ARRIVE WITH THE HIGH PRESSURE RIDGE. BUT H900 MOISTURE ONCE AGAIN LOOKS TO LINGER OVER THE AREA WED NIGHT INTO THURS MORNING. WITH H900 TEMPS AROUND -6.5C...SHOULD SEE SUFFICIENT LK INSTABILITY TO KEEP CLOUDS GOING AS WINDS VEER TO THE NE ON WED NIGHT INTO THURS MORNING. WILL TRY TO HOLD ONTO THE CLOUDS LONGER THAN THE MODELS ARE SHOWING...AS THEY HAD A DIFFICULT TIME WITH THE SIMILAR FEATURE YESTERDAY. ONCE THE LLVL MOISTURE DEPARTS OR IS MIXED OUT THURS MORNING...LOOKS TO BE A NICE DAY ON THURS WITH THE AREA UNDER THE HIGH PRESSURE RIDGE. COULD SEE THURS BEING VERY SIMILAR TO TODAY...WITH HUDSON BAY HIGH PRESSURE RIDGE OVER THE AREA AND TRYING TO PULL DRIER AIR INTO THE ERN CWA. WILL LOWER DEWPOINT VALUES 5-7 DEGREES FROM THE GOING MID 20S OVER THE EAST...AS MODEL MIXED TD VALUES INDICATE SINGLE DIGIT VALUES. MAY NEED TO DROP FURTHER IF TREND CONTINUES. EXTENDED /THURSDAY NIGHT THROUGH MONDAY/... SHORTWAVE APPROACHES THE AREA ON FRI...TRYING TO PUSH THROUGH THE UPPER RIDGE. 00-12Z GEM/GFS/ECMWF DIFFERING ON THE THIS SHORTWAVE AND ASSOCIATED SFC FEATURES...SO HAVE CHANCES MOVING INTO THE WRN CWA IN THE MORNING AND THEN EXPECT A DIMINISHING TREND AS THE SHORTWAVE WEAKENS WHILE HEADING E IN THE AFTN. WEAK UPPER AND SFC RIDGING PUSHES IN FOR FRI NIGHT AND SHOULD LEAD TO A DRY PERIOD...BEFORE NEXT WAVE APPROACHES FOR THE WEEKEND. 00-12Z ECMWF/GEM/GFS/UKMET RUNS VARY CONSIDERABLY WITH THIS WAVE...IN TIMING/LOCATION/STRENGTH. CONSENSUS IDEA IS THAT IT WILL PUSH ALONG THE US/CANADA BORDER IN THE NRN PLAINS ON FRI NIGHT...THEN SLIDE JUST N OF LK SUPERIOR ON SAT. THIS SHOULD KEEP MUCH OF THE PCPN TO THE N OF THE AREA...BUT THE GEM IS THE FARTHEST S AND STRONGER WITH THE LOW CENTER AND PUSHES IT ACROSS THE CWA. THIS WAVE WILL SLIDE E ON SAT NIGHT...LEADING TO WEAK RIDGING AGAIN ON SUN AND SUN NIGHT BEFORE NEXT WAVE SLIDES IN ON MON. OUT OF THE THREE WAVES IN THE EXTENDED...THE MONDAY FEATURE LOOKS TO BE THE MOST POTENT AND AFFECTING MUCH OF THE NCNTRL U.S. WILL MENTION CHANCES ON MON TO ACCOUNT FOR THIS. EXTENDED PERIOD LOOKS TO SEE ABOVE NORMAL TEMPERATURES...WITH GRADUAL WARMING HEADING THROUGH THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 123 PM EDT MON MAR 26 2012 EXPECT VFR CONDITIONS THRU AT LEAST THIS EVNG AS VERY DRY AIRMASS ASSOCIATED WITH HI PRES IN ONTARIO DOMINATES. THICKER MID CLDS/SOME MIXED PCPN IN ADVANCE OF A WARM FRONT WL ARRIVE TNGT...BUT LINGERING LLVL DRY AIR WL LIMIT THE POTENTIAL FOR LOWER CIG/VSBY. THIS LLVL DRY AIR WL LIKELY CAUSE SOME -FZRA...ESPECIALLY AT SAW WHERE UPSLOPE SSE WIND WL MAINTAIN LOWER TEMPS LONGER. AS THE LLVL S WIND INTENSIFIES TNGT AHEAD OF THE APRCHG WARM FNT...LLWS IS LIKELY TO IMPACT ALL 3 TAF SITES. THESE WINDS ARE LIKELY TO MIX TO THE SFC ON TUE FOLLOWING SOME LLVL WARMING/DESTABILIZATION. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 PM EDT MON MAR 26 2012 AS THE PRESSURE GRADIENT STRENGTHENS OVER THE UPPER GREAT LAKES BETWEEN A DEEPENING LO PRES SYSTEM MOVING E FROM THE NORTHERN PLAINS AND RETREATING HI PRES IN SE CANADA...EXPECT INCREASING SSE WINDS TO REACH GALE FORCE AND UP TO 40 KTS ON TUE OVER THE E HALF OF LAKE SUPERIOR FAVORED FOR STRONGER S WINDS DESPITE HI STABILITY OVER THE RELATIVELY CHILLY LAKE WATERS. AS THE LOW MOVES ACROSS LAKE SUPERIOR ON TUES NIGHT AND EXITS TO THE E ON WED...WIND WILL SHIFT TO THE NW AND GUST TO 30KTS TUES NIGHT. MARINE LAYER WILL LIKELY KEEP THE HIGHER WINDS ALOFT FROM REACHING THE SFC...SO DON/T THINK WE WILL SEE ANY GALES. HIGH PRESSURE RIDGE BUILDING IN WED AFTN AND NIGHT WILL DIMINISH THE WINDS BELOW 20KTS WITH WINDS GRADUALLY VEERING THROUGH THURS. A WEAK DISTURBANCE WILL PUSH ACROSS THE AREA ON FRI...BUT THE ESE WINDS SHOULD STAY BELOW 20KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FREEZING RAIN ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 11 AM EDT /10 AM CDT/ TUESDAY FOR MIZ004-005-010-011-084. FREEZING RAIN ADVISORY FROM 5 AM TO NOON EDT TUESDAY FOR MIZ006- 007-013-014-085. FREEZING RAIN ADVISORY FROM 11 PM EDT /10 PM CDT/ THIS EVENING TO 8 AM EDT /7 AM CDT/ TUESDAY FOR MIZ002-009. LAKE SUPERIOR... GALE WARNING FROM 10 AM TO 7 PM EDT TUESDAY FOR LSZ267. GALE WARNING FROM 7 AM TO 8 PM EDT TUESDAY FOR LSZ266. GALE WARNING FROM 8 AM TO 6 PM EDT TUESDAY FOR LSZ244-245-248- 249-264-265. GALE WARNING FROM 10 AM TO 6 PM EDT TUESDAY FOR LSZ250-251. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...KC SHORT TERM...KC LONG TERM...SRF AVIATION...KC MARINE...KC/SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1218 AM EDT MON MAR 26 2012 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 454 PM EDT SUN MAR 25 2012 LOW CLOUDS HAVE BEEN VERY PERSISTENT TODAY...AS THE H875 INVERSION HAS BEEN DIFFICULT TO ERRODE. AWAY FROM THE COOLING OFF LK SUPERIOR...THE CLOUDS HAVE MIXED OUT...BUT STILL HAVE A DECENT SWATH OF CLOUDS OVER SRN ONTARIO NEAR THUNDER BAY. MEANWHILE...1033MB SFC HIGH JUST NE OF LK WINNIPEG AND AN ASSOCIATED SFC RIDGE HAS BEEN WORKING INTO WRN LK SUPERIOR. FARTHER SW...DEVELOPING LOW OVER WYOMING AS LED TO SOME MID LVL WAA AND CLOUDS OVER SD AND SRN MN. THESE CLOUDS SHOULD STAY S OF THE AREA TONIGHT AS THE UPPER TROUGH DIGS OVER THE NEW ENGLAND STATES AND BRINGS DRIER MID LVL AIR INTO THE UPPER GREAT LKS. ISSUE FOR TONIGHT WILL BE THE CLOUDS NEAR/OVER LK SUPERIOR. WITH THE WAY THEY HAVE HUNG IN TODAY OVER THE KEWEENAW AND ERN LK...FEELING IS THAT THERE IS A GOOD CHANCE OF THEM HANGING AROUND FOR MUCH OF THE NIGHT. THERE SHOULD BE PLENTY OF LK INSTABILITY...AS H950-925 TEMPS ARE AROUND -9C AND LK TEMPS AROUND 3-4C. QUESTION WILL BE IF THE MOISTURE WILL REMAIN. THE MODELS HAVE BEEN HAVING A DIFFICULT TIME WITH THIS MOISTURE AND MOST HAVE THE MOISTURE DIMINISHING THIS EVENING WITH THE CONTINUED SUBSIDENCE AND DRY AIR WITH THE SFC RIDGE. BUT THE PERSISTENCE OF THE CLOUDS OVER SRN ONTARIO AND CNTRL/ERN LK SUPERIOR CREATES CONCERN ON IT COMPLETELY DIMINISHING. HAVE BUMPED UP CLOUDS TO PARTLY CLOUDY NEAR LK SUPERIOR FOR THE OVERNIGHT HOURS...AS TO SUBSIDENCE...ANTICYCLONIC FLOW...AND DECREASING MOISTURE UNDER THE HIGH PRESSURE RIDGE MAY BE ENOUGH TO DIMINISH THEM. THAT BEING SAID...COULD EASILY SEE THE MOISTURE BECOMING TRAPPED WITH LOSS OF HEATING AND REMAINING WITH THE LK INSTABILITY. DID TRY TO SHOW SOME MOVEMENT TO THE PARTLY CLOUDY SKY AS H925 WINDS VEER THROUGH THE NIGHT...WHICH WOULD FOCUS THE CLOUDS OVER THE N THEN NE FAVORED LOCATIONS. IN ADDITION...13-16Z RUC RUNS TRY TO DEVELOP LK ENHANCED PCPN OVER CNTRL/ERN LK SUPERIOR THIS EVENING AND THEN DROP IT INTO UPPER MI. THE ONLY OTHER HIRES MODEL TO MENTION IT WAS THE REGIONAL GEM. WITH A FEW SHOWERS DEVELOPING TODAY DEVELOPMENT WOULDN/T BE SURPRISING...BUT WITH CONCERNS ON AMNT OF MOISTURE PRESENT DECIDED TO LEAVE OUT. LOWS TONIGHT HAVE HIGH BUST POTENTIAL DUE TO SEVERAL INFLUENCES. NEAR LK SUPERIOR...THE CLOUDS/WIND WILL BE THE MAIN FACTOR. THE COMBINATION OF THE TWO CREATES UNCERTAINTY AND HAVE STUCK WITH A MIDDLE GROUND IN THE UPPER 20S. FARTHER INLAND...TEMPS COULD REALLY TANK ONCE THE WINDS DIMINISH THIS EVENING AND IF SKIES REMAIN MOSTLY CLEAR. PWATS AROUND 0.25IN OR ABOUT 40 PERCENT OF NORMAL AND LIGHT WINDS CREATES A GOOD RADIATIONAL COOLING NIGHT AND EXPECT TEMPS TO FALL NEAR 20. IF THE CLOUDS REMAIN AWAY...COULD SEE VALUES EVEN COLDER INTO THE TEENS OVER THE INTERIOR WEST COLD SPOTS. MONDAY...HIGH PRESSURE CENTERED JUST SW OF JAMES BAY WILL KEEP THE SFC RIDGE OVER THE AREA...WHILE AN UPPER RIDGE WILL START TO BUILD OVER THE NRN PLAINS. RIDGE WILL GRADUALLY SHIFT E THROUGH THE DAY...AS SFC LOW DEVELOPS OVER ERN MONTANA/WYOMING. OTHER THAN THE PREVIOUSLY MENTIONED POTENTIAL FOR LINGERING LK CLOUDS IN THE MORNING...DRY AIR AND SUBSIDENCE FROM THE HIGH SHOULD LEAD TO A MOSTLY SUNNY DAY. MID CLOUDS DEVELOPING UNDER H700 WAA MON AFTN OVER MN AND NW WI...AND WILL APPROACH THE FAR WRN CWA LATE IN THE AFTN. COOL NRLY FLOW OFF LK SUPERIOR WILL KEEP MIXING DOWN NEAR THE LK SHORE AND KEEP HIGHS IN THE 30S. FARTHER INLAND AWAY FROM THE LK INFLUENCE...MIXING TOWARDS H850 TEMPS OF -4C WEST AND -9C EAST WILL PRODUCE HIGHS IN THE LOW-MID 40S...ESPECIALLY ALONG THE WI BORDER. AS FOR DEWPOINTS...MODEL MIXED LAYER DEWPOINT VALUES ARE IN THE LOW SINGLE DIGITS ABOVE ZERO OVER THE E HALF OF THE LAND CWA. THIS HAS BEEN CONSISTENT OVER THE LAST SEVERAL RUNS...SO HAVE ADJUSTED GOING VALUES DOWN A TOUCH AWAY FROM THE MOISTENING AFFECTS OF LK SUPERIOR. THIS LEADS TO RH VALUES FALLING INTO THE UPPER 20S...WITH A FEW MID-LOWER 20S OVER THE ERN CWA. WITH WINDS MAINLY 10KTS OR LESS AND ALONG WITH THE COOLER TEMPS...EXPECT FIRE WX CONCERNS TO BE LIMITED. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 454 PM EDT SUN MAR 25 2012 MONDAY NIGHT AND TUE...THE GFS...ECMWF AND NAM HAVE BEEN CONSISTENT AND WERE IN REASONABLY GOOD AGREEMENT WITH THE SHORTWAVE LIFTING FROM THE PLAINS TO THE NRN GREAT LAKES. STRONG WAA AND 295K- 305K ISENTROPIC LIFT (NOSE OF 850-800MB WINDS 50-55KT) WILL SUPPORT A BAND OF PCPN THROUGH THE CWA LATE MONDAY NIGHT INTO TUESDAY MORNING. THE VERY STRONG WAA IN THE 850-700 MB LAYER PUSHING WARM NOSE TEMPS TO AROUND 5C SHOULD LEAD TO MOSTLY LIQUID PCPN. WITH INCREASING CLOUDS AND WAA OVER THE FAR WEST EXPECT THAT SFC TEMPS SHOULD REBOUND ENOUGH BY THE ONSET OF PCPN TO KEEP PCPN AS RAIN. HOWEVER...OVER INTERIOR WEST AND CENTRAL UPPER MICHIGAN TEMPS INTO THE UPPER 20S TO AROUND 30 MAY LINGER AS THE PCPN MOVES IN. EVAPORATIVE COOLING AT THE ONSET OF PCPN WILL ALSO DELAY LOW LEVEL WARMING. WITH RELATIVELY WARM GROUND TEMPERATURES AFTER THE LONG WARM SPELL...THERE IS ADDITIONAL UNCERTAINTY ON HOW MUCH ICE IF ANY WOULD ACCUMULATE. SO...MENTIONED BOTH RA/FZRA FOR MOST OF THE THE CWA AND HIGHLIGHTED THE HAZARD IN A PORTION OF THE SPS. INSTABILITY FOR TSRA LOOKS MARGINAL...BUT SOME ELEVATED CAPE INTO EDING INTO THE CWA SUPPORTS AT LEAST CONTINUED MENTION OF SLIGHT CHANCE FOR TSRA. TUE NIGHT INTO WED...AS THE DRY SLOT SPREADS ACROSS THE ARA LATE TUE INTO TUE EVENING...PCPN SHOULD DIMINISH TO AREAS OF DRIZZLE OR ISOLATED SHOWERS DURING THE AFTERNOON AND EVENING. AS THE MID LEVEL LOW MOVES OFF TO THE NORTHEAST OF LAKE SUPERIOR AND A TRAILING SHORTWAVE MOVES THROUGH UPPER MI SOME ADDITIONAL WRAP-AROUND LIGHT SHOWERS MAY BE POSSIBLE WED MORNNG. BY THE TIME THE COLDER AIR ARRIVES WED AFTERNOON...DRIER AIR WILL ALSO SPREAD INTO THE REGION. SO...ONLY LOW END POPS FOR SOME LIGHT LAKE ENHANCED PCPN. THU-SUN...HIGH PRES SHOULD BUILD INTO THE AREA THU WITH COOL DRY AND MOSTLY SUNNY CONDITIONS. MODELS CONTINUE TO SUGGEST POTENTIAL FOR ANOTHER SHRTWV AND PCPN CHANCES MOVING INTO THE AREA THU NIGHT INTO FRIDAY EVEN THOUGH CONFIDECNE IN DETAILS IS LOW. A BLOCKING RIDGE TO THE NORTH WITH A SFC HUDSON BAY HIGH EXTENDEDING INTO THE AREA WILL LIMIT PCPN CHANCES TO LOWER END POPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1212 AM EDT MON MAR 26 2012 MAIN FCST ISSUE OVERNIGHT IS STRATOCU OFF THE LAKE. WITH LOW-LEVEL WINDS VEERING FROM NORTHERLY TO NORTHEASTERLY...KSAW WILL BE FAVORED FOR BKN MVFR CIGS ABOVE 2000FT...ESPECIALLY WITH STRATOCU E AND NE OF LAKE SUPERIOR PER SATELLITE IMAGERY. THE CLOUDS WILL SCATTER OUT AT TIMES. EXPECT CLOUDS AT KSAW TO CLEAR OUT MID TO LATE MORNING WITH VFR CONDITIONS CONTINUING THRU THE END OF THIS FCST PERIOD. AT KCMX/KIWD...VFR CONDITIONS WILL PREVAIL. NOT EXPECTING ANYTHING MORE THAN SCT STRATOCU AT KCMX OVERNIGHT WITH UNFAVORABLE WIND DOWN THE SPINE OF THE KEWEENAW...AND CLEAR SKIES SHOULD DOMINATE AT KIWD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 454 PM EDT SUN MAR 25 2012 HIGH PRESSURE RIDGE MOVING INTO LAKE SUPERIOR TONIGHT WILL GRADUALLY DIMINISH THE PRESSURE GRADIENT OVER LAKE SUPERIOR AND LEAD TO A GRADUAL DIMINISHING TREND IN THE VEERING WINDS TONIGHT INTO MONDAY MORNING. AS THE LOW SHIFTS E ON MONDAY...A LOW PRESSURE SYSTEM DEVELOPING IN THE NRN PLAINS WILL SHIFT EAST AND ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT AND WEDNESDAY. THIS COULD PRODUCE A SOUTHERLY GALE FORCE GUSTS TO 35KTS ON TUESDAY OVER EASTERN LAKE SUPERIOR. HIGH PRESSURE RIDGE WILL THEN BUILD OVER THE UPPER GREAT LAKES WED NIGHT AND THURSDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM TUESDAY MORNING THROUGH TUESDAY AFTERNOON FOR LSZ266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...JLB AVIATION...ROLFSON MARINE...SRF
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
330 PM CDT MON MAR 26 2012 .DISCUSSION.. WATER VAPOR IMAGERY THIS AFTERNOON SHOWING FEATURE OF INTEREST... SHORTWAVE TROF...CROSSING THE ROCKIES. MODELS IN QUITE GOOD AGREEMENT THIS WAVE WILL LIFT QUICKLY ACROSS THE NORTHERN PLAINS AND NEAR THE WESTERN GREAT LAKES REGION BY TUESDAY AFTERNOON. ATTENDANT SFC LOW CURRENTLY OVER NRN WY WILL DEEPEN SIGNIFICANTLY THROUGH TONIGHT AS 500MB HEIGHT FALLS DROP 16DAM. INCOMING FRONT WITH THIS SYSTEM WILL BE THE FOCUS FOR POSSIBLE THUNDER SOMETIME AFTER 06Z. HIRES WRF AND RUC13 ARE ADVERTISING MODERATE INSTABILITY ALONG WITH DECENT MOISTURE POOLING ALONG THE BNDRY/SFC TROF WITH BEST CHANCE FOR DEVELOPMENT MAINLY SOUTH OF I-80. ON TUESDAY TIGHT SURFACE PRESSURE GRADIENT SHOULD PREVAIL OVER MOST OF THE REGION... PARTICULARLY NORTH. FIRE WEATHER ISSUE COMING TO PLAY THEN TUESDAY AFTERNOON AS COMBINATION OF WIND AND MIXING DRIVES DEW POINTS/RH DOWN CLOSE TO RED FLAG WARNING CRITERIA. FOCUS FOR THUNDER THEN SHIFTS TO THE SOUTH WEDNESDAY/WEDNESDAY NIGHT AS BOUNDARY LAYER MOISTURE CONVERGENCE INCREASES/INSTABILITY AXIS SETS UP ALONG THE NEB/KS BORDER...THEN RE-ORIENTS THURSDAY/THURSDAY NIGHT OVER THE CWA. AS FOR DAY 4-7...AT THIS POINT NOT INCLINED TO MAKE ANY SIGNIFICANT CHANGES TO THE FORECAST DUE TO SIGNIFICANT GFS/ECM DIFFERENCES PER LATEST RUN. OTHERWISE STILL LOOKING LIKE MAX TEMPS WILL BE HOVERING AROUND 20 DEG ABOVE NORM HEADING INTO NEXT WEEKEND. DEE && .AVIATION... 18Z TAFS FOR KOMA...KLNK...AND KOFK. MAIN CONCERNS THROUGH THE PERIOD WILL BE WINDS. INITIALLY...WINDS FROM THE SOUTHEAST AROUND 150-170 DEGREES SUSTAINED AT 25 TO 28KTS... WITH GUSTS UP TO 35 TO 38KTS. SHOULD LOSE THE GUSTS AT KLNK/KOMA BY ABOUT 27/00Z. A FRONT MOVING INTO THE AREA WILL ALSO BRING A WIND SHIFT...ALONG WITH A SMALL CHANCE FOR CONVECTION LATER TONIGHT AS WELL. BEST CHANCE APPEARS TO BE AT KLNK/KOMA...IN THE 07Z-11Z PERIOD. WINDS BECOME WEST AFTER THE TROUGH MOVES THROUGH...BECOMING GUSTY AGAIN BY 27/15Z. DEWALD .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ045-052-053-066-067-078-088-089. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ015-033-034- 043>045-050>053-065-066-078. RED FLAG WARNING FROM NOON TO 8 PM CDT TUESDAY FOR NEZ011-012- 015>018-030>034-042>044-050-051-065. WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR NEZ011-012- 016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ055-056-069. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ043-055. RED FLAG WARNING FROM NOON TO 8 PM CDT TUESDAY FOR IAZ043. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1215 PM CDT MON MAR 26 2012 .AVIATION...18Z TAFS FOR KOMA...KLNK AND KOFK. MAIN CONCERNS THROUGH THE PERIOD WILL BE WINDS. INITIALLY...WINDS FROM THE SOUTHEAST AROUND 150-170 DEGREES SUSTAINED AT 25 TO 28KTS...WITH GUSTS UP TO 35 TO 38KTS. SHOULD LOSE THE GUSTS AT KLNK/KOMA BY ABOUT 27/00Z. A FRONT MOVING INTO THE AREA WILL ALSO BRING A WIND SHIFT...ALONG WITH A SMALL CHANCE FOR CONVECTION LATER TONIGHT AS WELL. BEST CHANCE APPEARS TO BE AT KLNK/KOMA...IN THE 07Z-11Z PERIOD. WINDS BECOME WEST AFTER THE TROUGH MOVES THROUGH...BECOMING GUSTY AGAIN BY 27/15Z. DEWALD && .PREV DISCUSSION... /ISSUED 1039 AM CDT MON MAR 26 2012/ DISCUSSION... UPDATED THE FORECAST TO REMOVE CHANCE OF RAIN FOR THE REST OF THE MORNING IN WESTERN IOWA. ALSO EXPANDED THE WIND ADVISORY ONE MORE TIER OF COUNTIES FURTHER EAST...INTO THE LINCOLN AND OMAHA METRO AREAS AS THESE LOCATIONS SHOULD BE JUST ON THE EDGE OF THE ADVISORY LEVEL WIND SPEEDS. DEWALD PREV DISCUSSION... /ISSUED 754 AM CDT MON MAR 26 2012/ DISCUSSION... HAVE INCREASED POPS ALONG AND EAST OF THE MISSOURI RIVER...AS SHOWERS FINALLY HAVE DEVELOPED IN A BAND FROM AROUND BLAIR TO PLATTSMOUTH TO NEBRASKA CITY. SO FAR...NO LIGHTNING HAS BEEN DETECTED...BUT STILL THINK A FEW STRIKES ARE POSSIBLE...AND KEPT ISOLATED WORDING IN THE GRIDS. MAYES PREV DISCUSSION... /ISSUED 646 AM CDT MON MAR 26 2012/ DISCUSSION... MAIN CONCERN OVER THE NEXT 30 HOURS IS THE POTENT UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. THIS IS PROGGED TO TAKE A TRACK NEWD TODAY AND MOVE THROUGH THE NORTHERN PLAINS TONIGHT AND TUE. AHEAD OF THE STRONG SYSTEM LOW LEVEL WAA IS CURRENTLY TAKING PLACE ACROSS THE REGION. MODELS SEEM TO HAVE A HIGH BIAS WITH THE MOISTURE ATTM...AND THUS A LITTLE BULLISH ON THE CONVECTIVE POTENTIAL FOR THE REST OF THE NIGHT. LATEST RUC ANALYSIS DOES INDC AROUND 500-1000 J/KG OF MUCAPE OVER THE WRN CWA...BUT POINT FORECAST SOUNDINGS INDC THIS MOISTURE IS RATHER SHALLOW AROUND 850 MB AND THERE IS A GOOD DEAL OF CIN HOLDING BACK THE CONVECTION. WE FEEL THIS TREND WILL CONT TONIGHT...BUT WILL MAINTAIN A SLIGHT CHANCE POPS B/W 12-15Z OVER THE CNTRL AND SERN CWA FOR ANYTHING ISO THAT MAY DEVELOP. OTHERWISE ANOTHER WINDY AND WARM DAY IS IN STORE FOR THE FA. WINDS AT 925 (850) MB INCREASE TO 40 (55) KT BY THIS AFTERNOON AND WITH THE INCREASING PRESSURE GRADIENT...SOME OF THIS SHOULD MAKE IT TO NEAR THE SURFACE. HIGH CLOUDS WILL LIKELY LIMIT MIXING THOUGH...AND WE WOULD FEEL BETTER WITH A DUE SOUTH OR SW WIND...SO A WIND ADVRY IS NO SLAM DUNK...BUT WITH THE PRESSURE GRADIENT AND MIXING TO 925 MB WE WILL LIKELY SEE A FEW SITES MEET CRITERIA THIS AFTN INTO THE EVNG HOURS. THUS WE HAVE ISSUED A WIND ADVISORY. THE DRY LINE STILL LOOKS TO SET UP OVER THE WRN HI PLAINS TODAY AS THE UPPER LEVEL SYSTEM MOVES TOWARD THE REGION. SOME POSITIVE CAPE IS INDICATED NEAR THE DRY LINE...BUT CIN IS SIGNIFICANT AND WITH MUCH OF THE FORCING GOING INTO SODAK...CONVECTIVE POTENTIAL FOR THE NEB AREA LOOKS PRETTY LOW...AND ESPECIALLY ANYTHING THAT WOULD WORK INTO OUR FA. THUS HAVE REDUCED POPS TO SCHC FOR THIS EVNG IN THE NW. A LITTLE BETTER CHC OF SHOWERS/STORMS MAY ACTUALLY COME AFTER MIDNIGHT IN THE ERN FA AS BETTER MOISTURE INTERACTS WITH THE ADVANCING PAC CDFNT AS IT MOVES THROUGH THE AREA. WILL CONT SOME CHC POPS IN THE E AFTER MIDNIGHT FOR THIS. THE SYSTEM SHOULD BE CLEAR OF THE FA BY TUES MRNG WITH ANOTHER WARM AND DRY DAY EXPECTED FOR TUE/WED. THE SURFACE FNT STILL LOOKS TO HANG UP OVER MO/KS ON TUE/WED AND THIS WILL START TO RETREAT NWD WED NIGHT AND INTO THE DAY ON THU (ALTHOUGH I HAVE MY DOUBTS THAT IT WILL ACTUALLY MAKE IT INTO NEB). AS THE LOW LEVEL WAA INCREASES AHEAD OF A SHRTWV PROGGED FOR THU NIGHT SOME MOISTURE WILL LIKELY WORK AROUND THE FNT AND INTO CNTRL NEB BY LATE THU WHICH SHOULD ALLOW FOR A CHANCE OF SHOWERS/STORMS LATE THU...THU NIGHT AND INTO FRI. SIGNIFICANT DIFFERENCES THEN DEVELOP BETWEEN THE GFS AND EC FOR NEXT WEEKEND AND NO CHANGES WERE MADE PAST FRI. BOUSTEAD FIRE WEATHER... IN THE POST FRONT AIRMASS ON TUES THE AIR MASS IS EXPECTED TO DRY OUT SIGNIFICANTLY. DEEP MIXING TO AROUND 850 MB OR HIGHER WILL LEAD TO DEWPOINTS FALLING THROUGH A GOOD PART OF THE DAY IN THE CNTRL AND WRN CWA. DESPITE THE FRONT MOVING THROUGH...TEMPERATURES WITH THE MIXING ON TUES WILL LIKELY CLIMB BACK INTO THE MID AND EVEN SOME UPPER 70S. THIS WILL CREATE SEVERAL HOURS OF RH BELOW 20 PERCENT DURING THE AFTN ON TUES. WITH STRONGLY UNIDIRECTIONAL FLOW AND A DECENT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE SURFACE LOW OVER SD...SFC WINDS SHOULD BE SUSTAINED ABOVE 15 KT WITH GUSTS WELL OVER 25 KT. THIS ALL SHOULD COMBINED FOR A DANGEROUS FIRE WX DAY...ALTHOUGH WE ARE STARTING TO GREEN UP NICELY AROUND THE AREA...AND THUS HAVE ISSUED A FIRE WEATHER WATCH FOR TUES FOR A LARGE PART OF THE AREA. BOUSTEAD/MAYES && .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ011-012-015>018-030>034-042>045-050>053- 065>067-078-088-089. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ015-033-034- 043>045-050>053-065-066-078. WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR NEZ011-012- 016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ043-055. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ043-055. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1039 AM CDT MON MAR 26 2012 .DISCUSSION... UPDATED THE FORECAST TO REMOVE CHANCE OF RAIN FOR THE REST OF THE MORNING IN WESTERN IOWA. ALSO EXPANDED THE WIND ADVISORY ONE MORE TIER OF COUNTIES FURTHER EAST...INTO THE LINCOLN AND OMAHA METRO AREAS AS THESE LOCATIONS SHOULD BE JUST ON THE EDGE OF THE ADVISORY LEVEL WIND SPEEDS. DEWALD && .PREV DISCUSSION... /ISSUED 754 AM CDT MON MAR 26 2012/ DISCUSSION... HAVE INCREASED POPS ALONG AND EAST OF THE MISSOURI RIVER...AS SHOWERS FINALLY HAVE DEVELOPED IN A BAND FROM AROUND BLAIR TO PLATTSMOUTH TO NEBRASKA CITY. SO FAR...NO LIGHTNING HAS BEEN DETECTED...BUT STILL THINK A FEW STRIKES ARE POSSIBLE...AND KEPT ISOLATED WORDING IN THE GRIDS. MAYES PREV DISCUSSION... /ISSUED 646 AM CDT MON MAR 26 2012/ AVIATION... 12Z TAFS FOR KOMA...KLNK...AND KOFK. VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE TAF CYCLE. SOME MID-LEVEL CIGS WILL INTERMITTENTLY AFFECT ALL SITES. SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE LATE TONIGHT...WITH KOMA THE MOST LIKELY SITE TO BE AFFECTED. CONFIDENCE IS LOW ON BOTH OCCURRENCE AND COVERAGE THOUGH...AND HAVE KEPT MENTION OUT OF THE TAF FOR NOW. WINDS WILL BE THE BIGGEST CONCERN...WITH SOUTH- SOUTHEAST WINDS GUSTING THIS AFTERNOON AND EARLY EVENING UP TO 30-35KT AT KOMA/KLNK...AND UP TO AROUND 35-40KT AT KOFK. SPEEDS WILL DIMINISH LATE TONIGHT AS A FRONT BRING A WIND SHIFT TO WESTERLY...AFFECTING KOFK EARLIEST...AND KOMA/KLNK AT THE END OF THE TAF CYCLE OR JUST OUTSIDE OF IT. MAYES PREV DISCUSSION... /ISSUED 342 AM CDT MON MAR 26 2012/ DISCUSSION... MAIN CONCERN OVER THE NEXT 30 HOURS IS THE POTENT UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. THIS IS PROGGED TO TAKE A TRACK NEWD TODAY AND MOVE THROUGH THE NORTHERN PLAINS TONIGHT AND TUE. AHEAD OF THE STRONG SYSTEM LOW LEVEL WAA IS CURRENTLY TAKING PLACE ACROSS THE REGION. MODELS SEEM TO HAVE A HIGH BIAS WITH THE MOISTURE ATTM...AND THUS A LITTLE BULLISH ON THE CONVECTIVE POTENTIAL FOR THE REST OF THE NIGHT. LATEST RUC ANALYSIS DOES INDC AROUND 500-1000 J/KG OF MUCAPE OVER THE WRN CWA...BUT POINT FORECAST SOUNDINGS INDC THIS MOISTURE IS RATHER SHALLOW AROUND 850 MB AND THERE IS A GOOD DEAL OF CIN HOLDING BACK THE CONVECTION. WE FEEL THIS TREND WILL CONT TONIGHT...BUT WILL MAINTAIN A SLIGHT CHANCE POPS B/W 12-15Z OVER THE CNTRL AND SERN CWA FOR ANYTHING ISO THAT MAY DEVELOP. OTHERWISE ANOTHER WINDY AND WARM DAY IS IN STORE FOR THE FA. WINDS AT 925 (850) MB INCREASE TO 40 (55) KT BY THIS AFTERNOON AND WITH THE INCREASING PRESSURE GRADIENT...SOME OF THIS SHOULD MAKE IT TO NEAR THE SURFACE. HIGH CLOUDS WILL LIKELY LIMIT MIXING THOUGH...AND WE WOULD FEEL BETTER WITH A DUE SOUTH OR SW WIND...SO A WIND ADVRY IS NO SLAM DUNK...BUT WITH THE PRESSURE GRADIENT AND MIXING TO 925 MB WE WILL LIKELY SEE A FEW SITES MEET CRITERIA THIS AFTN INTO THE EVNG HOURS. THUS WE HAVE ISSUED A WIND ADVISORY. THE DRY LINE STILL LOOKS TO SET UP OVER THE WRN HI PLAINS TODAY AS THE UPPER LEVEL SYSTEM MOVES TOWARD THE REGION. SOME POSITIVE CAPE IS INDICATED NEAR THE DRY LINE...BUT CIN IS SIGNIFICANT AND WITH MUCH OF THE FORCING GOING INTO SODAK...CONVECTIVE POTENTIAL FOR THE NEB AREA LOOKS PRETTY LOW...AND ESPECIALLY ANYTHING THAT WOULD WORK INTO OUR FA. THUS HAVE REDUCED POPS TO SCHC FOR THIS EVNG IN THE NW. A LITTLE BETTER CHC OF SHOWERS/STORMS MAY ACTUALLY COME AFTER MIDNIGHT IN THE ERN FA AS BETTER MOISTURE INTERACTS WITH THE ADVANCING PAC CDFNT AS IT MOVES THROUGH THE AREA. WILL CONT SOME CHC POPS IN THE E AFTER MIDNIGHT FOR THIS. THE SYSTEM SHOULD BE CLEAR OF THE FA BY TUES MRNG WITH ANOTHER WARM AND DRY DAY EXPECTED FOR TUE/WED. THE SURFACE FNT STILL LOOKS TO HANG UP OVER MO/KS ON TUE/WED AND THIS WILL START TO RETREAT NWD WED NIGHT AND INTO THE DAY ON THU (ALTHOUGH I HAVE MY DOUBTS THAT IT WILL ACTUALLY MAKE IT INTO NEB). AS THE LOW LEVEL WAA INCREASES AHEAD OF A SHRTWV PROGGED FOR THU NIGHT SOME MOISTURE WILL LIKELY WORK AROUND THE FNT AND INTO CNTRL NEB BY LATE THU WHICH SHOULD ALLOW FOR A CHANCE OF SHOWERS/STORMS LATE THU...THU NIGHT AND INTO FRI. SIGNIFICANT DIFFERENCES THEN DEVELOP BETWEEN THE GFS AND EC FOR NEXT WEEKEND AND NO CHANGES WERE MADE PAST FRI. BOUSTEAD FIRE WEATHER... IN THE POST FRONT AIRMASS ON TUES THE AIR MASS IS EXPECTED TO DRY OUT SIGNIFICANTLY. DEEP MIXING TO AROUND 850 MB OR HIGHER WILL LEAD TO DEWPOINTS FALLING THROUGH A GOOD PART OF THE DAY IN THE CNTRL AND WRN CWA. DESPITE THE FRONT MOVING THROUGH...TEMPERATURES WITH THE MIXING ON TUES WILL LIKELY CLIMB BACK INTO THE MID AND EVEN SOME UPPER 70S. THIS WILL CREATE SEVERAL HOURS OF RH BELOW 20 PERCENT DURING THE AFTN ON TUES. WITH STRONGLY UNIDIRECTIONAL FLOW AND A DECENT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE SURFACE LOW OVER SD...SFC WINDS SHOULD BE SUSTAINED ABOVE 15 KT WITH GUSTS WELL OVER 25 KT. THIS ALL SHOULD COMBINED FOR A DANGEROUS FIRE WX DAY...ALTHOUGH WE ARE STARTING TO GREEN UP NICELY AROUND THE AREA...AND THUS HAVE ISSUED A FIRE WEATHER WATCH FOR TUES FOR A LARGE PART OF THE AREA. BOUSTEAD/MAYES && .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ011-012-015>018-030>034-042>045-050>053- 065>067-078-088-089. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ015-033-034- 043>045-050>053-065-066-078. WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR NEZ011-012- 016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ043-055. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ043-055. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
754 AM CDT MON MAR 26 2012 .DISCUSSION... HAVE INCREASED POPS ALONG AND EAST OF THE MISSOURI RIVER...AS SHOWERS FINALLY HAVE DEVELOPED IN A BAND FROM AROUND BLAIR TO PLATTSMOUTH TO NEBRASKA CITY. SO FAR...NO LIGHTNING HAS BEEN DETECTED...BUT STILL THINK A FEW STRIKES ARE POSSIBLE...AND KEPT ISOLATED WORDING IN THE GRIDS. MAYES && .PREV DISCUSSION... /ISSUED 646 AM CDT MON MAR 26 2012/ AVIATION... 12Z TAFS FOR KOMA...KLNK...AND KOFK. VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE TAF CYCLE. SOME MID-LEVEL CIGS WILL INTERMITTENTLY AFFECT ALL SITES. SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE LATE TONIGHT...WITH KOMA THE MOST LIKELY SITE TO BE AFFECTED. CONFIDENCE IS LOW ON BOTH OCCURRENCE AND COVERAGE THOUGH...AND HAVE KEPT MENTION OUT OF THE TAF FOR NOW. WINDS WILL BE THE BIGGEST CONCERN...WITH SOUTH- SOUTHEAST WINDS GUSTING THIS AFTERNOON AND EARLY EVENING UP TO 30-35KT AT KOMA/KLNK...AND UP TO AROUND 35-40KT AT KOFK. SPEEDS WILL DIMINISH LATE TONIGHT AS A FRONT BRING A WIND SHIFT TO WESTERLY...AFFECTING KOFK EARLIEST...AND KOMA/KLNK AT THE END OF THE TAF CYCLE OR JUST OUTSIDE OF IT. MAYES PREV DISCUSSION... /ISSUED 342 AM CDT MON MAR 26 2012/ DISCUSSION... MAIN CONCERN OVER THE NEXT 30 HOURS IS THE POTENT UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. THIS IS PROGGED TO TAKE A TRACK NEWD TODAY AND MOVE THROUGH THE NORTHERN PLAINS TONIGHT AND TUE. AHEAD OF THE STRONG SYSTEM LOW LEVEL WAA IS CURRENTLY TAKING PLACE ACROSS THE REGION. MODELS SEEM TO HAVE A HIGH BIAS WITH THE MOISTURE ATTM...AND THUS A LITTLE BULLISH ON THE CONVECTIVE POTENTIAL FOR THE REST OF THE NIGHT. LATEST RUC ANALYSIS DOES INDC AROUND 500-1000 J/KG OF MUCAPE OVER THE WRN CWA...BUT POINT FORECAST SOUNDINGS INDC THIS MOISTURE IS RATHER SHALLOW AROUND 850 MB AND THERE IS A GOOD DEAL OF CIN HOLDING BACK THE CONVECTION. WE FEEL THIS TREND WILL CONT TONIGHT...BUT WILL MAINTAIN A SLIGHT CHANCE POPS B/W 12-15Z OVER THE CNTRL AND SERN CWA FOR ANYTHING ISO THAT MAY DEVELOP. OTHERWISE ANOTHER WINDY AND WARM DAY IS IN STORE FOR THE FA. WINDS AT 925 (850) MB INCREASE TO 40 (55) KT BY THIS AFTERNOON AND WITH THE INCREASING PRESSURE GRADIENT...SOME OF THIS SHOULD MAKE IT TO NEAR THE SURFACE. HIGH CLOUDS WILL LIKELY LIMIT MIXING THOUGH...AND WE WOULD FEEL BETTER WITH A DUE SOUTH OR SW WIND...SO A WIND ADVRY IS NO SLAM DUNK...BUT WITH THE PRESSURE GRADIENT AND MIXING TO 925 MB WE WILL LIKELY SEE A FEW SITES MEET CRITERIA THIS AFTN INTO THE EVNG HOURS. THUS WE HAVE ISSUED A WIND ADVISORY. THE DRY LINE STILL LOOKS TO SET UP OVER THE WRN HI PLAINS TODAY AS THE UPPER LEVEL SYSTEM MOVES TOWARD THE REGION. SOME POSITIVE CAPE IS INDICATED NEAR THE DRY LINE...BUT CIN IS SIGNIFICANT AND WITH MUCH OF THE FORCING GOING INTO SODAK...CONVECTIVE POTENTIAL FOR THE NEB AREA LOOKS PRETTY LOW...AND ESPECIALLY ANYTHING THAT WOULD WORK INTO OUR FA. THUS HAVE REDUCED POPS TO SCHC FOR THIS EVNG IN THE NW. A LITTLE BETTER CHC OF SHOWERS/STORMS MAY ACTUALLY COME AFTER MIDNIGHT IN THE ERN FA AS BETTER MOISTURE INTERACTS WITH THE ADVANCING PAC CDFNT AS IT MOVES THROUGH THE AREA. WILL CONT SOME CHC POPS IN THE E AFTER MIDNIGHT FOR THIS. THE SYSTEM SHOULD BE CLEAR OF THE FA BY TUES MRNG WITH ANOTHER WARM AND DRY DAY EXPECTED FOR TUE/WED. THE SURFACE FNT STILL LOOKS TO HANG UP OVER MO/KS ON TUE/WED AND THIS WILL START TO RETREAT NWD WED NIGHT AND INTO THE DAY ON THU (ALTHOUGH I HAVE MY DOUBTS THAT IT WILL ACTUALLY MAKE IT INTO NEB). AS THE LOW LEVEL WAA INCREASES AHEAD OF A SHRTWV PROGGED FOR THU NIGHT SOME MOISTURE WILL LIKELY WORK AROUND THE FNT AND INTO CNTRL NEB BY LATE THU WHICH SHOULD ALLOW FOR A CHANCE OF SHOWERS/STORMS LATE THU...THU NIGHT AND INTO FRI. SIGNIFICANT DIFFERENCES THEN DEVELOP BETWEEN THE GFS AND EC FOR NEXT WEEKEND AND NO CHANGES WERE MADE PAST FRI. BOUSTEAD FIRE WEATHER... IN THE POST FRONT AIRMASS ON TUES THE AIR MASS IS EXPECTED TO DRY OUT SIGNIFICANTLY. DEEP MIXING TO AROUND 850 MB OR HIGHER WILL LEAD TO DEWPOINTS FALLING THROUGH A GOOD PART OF THE DAY IN THE CNTRL AND WRN CWA. DESPITE THE FRONT MOVING THROUGH...TEMPERATURES WITH THE MIXING ON TUES WILL LIKELY CLIMB BACK INTO THE MID AND EVEN SOME UPPER 70S. THIS WILL CREATE SEVERAL HOURS OF RH BELOW 20 PERCENT DURING THE AFTN ON TUES. WITH STRONGLY UNIDIRECTIONAL FLOW AND A DECENT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE SURFACE LOW OVER SD...SFC WINDS SHOULD BE SUSTAINED ABOVE 15 KT WITH GUSTS WELL OVER 25 KT. THIS ALL SHOULD COMBINED FOR A DANGEROUS FIRE WX DAY...ALTHOUGH WE ARE STARTING TO GREEN UP NICELY AROUND THE AREA...AND THUS HAVE ISSUED A FIRE WEATHER WATCH FOR TUES FOR A LARGE PART OF THE AREA. BOUSTEAD/MAYES && .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ011-012-015>018-030>034-042>045-050>053- 065>067-078-088-089. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 7 PM CDT THIS EVENING FOR NEZ015-033-043-044-050-051-065-078. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM CDT THIS EVENING FOR NEZ011-012-016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ043-055. && $$ 99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
646 AM CDT MON MAR 26 2012 .AVIATION... 12Z TAFS FOR KOMA...KLNK...AND KOFK. VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE TAF CYCLE. SOME MID-LEVEL CIGS WILL INTERMITTENTLY AFFECT ALL SITES. SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE LATE TONIGHT...WITH KOMA THE MOST LIKELY SITE TO BE AFFECTED. CONFIDENCE IS LOW ON BOTH OCCURRENCE AND COVERAGE THOUGH...AND HAVE KEPT MENTION OUT OF THE TAF FOR NOW. WINDS WILL BE THE BIGGEST CONCERN...WITH SOUTH- SOUTHEAST WINDS GUSTING THIS AFTERNOON AND EARLY EVENING UP TO 30-35KT AT KOMA/KLNK...AND UP TO AROUND 35-40KT AT KOFK. SPEEDS WILL DIMINISH LATE TONIGHT AS A FRONT BRING A WIND SHIFT TO WESTERLY...AFFECTING KOFK EARLIEST...AND KOMA/KLNK AT THE END OF THE TAF CYCLE OR JUST OUTSIDE OF IT. MAYES && .PREV DISCUSSION... /ISSUED 342 AM CDT MON MAR 26 2012/ DISCUSSION... MAIN CONCERN OVER THE NEXT 30 HOURS IS THE POTENT UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. THIS IS PROGGED TO TAKE A TRACK NEWD TODAY AND MOVE THROUGH THE NORTHERN PLAINS TONIGHT AND TUE. AHEAD OF THE STRONG SYSTEM LOW LEVEL WAA IS CURRENTLY TAKING PLACE ACROSS THE REGION. MODELS SEEM TO HAVE A HIGH BIAS WITH THE MOISTURE ATTM...AND THUS A LITTLE BULLISH ON THE CONVECTIVE POTENTIAL FOR THE REST OF THE NIGHT. LATEST RUC ANALYSIS DOES INDC AROUND 500-1000 J/KG OF MUCAPE OVER THE WRN CWA...BUT POINT FORECAST SOUNDINGS INDC THIS MOISTURE IS RATHER SHALLOW AROUND 850 MB AND THERE IS A GOOD DEAL OF CIN HOLDING BACK THE CONVECTION. WE FEEL THIS TREND WILL CONT TONIGHT...BUT WILL MAINTAIN A SLIGHT CHANCE POPS B/W 12-15Z OVER THE CNTRL AND SERN CWA FOR ANYTHING ISO THAT MAY DEVELOP. OTHERWISE ANOTHER WINDY AND WARM DAY IS IN STORE FOR THE FA. WINDS AT 925 (850) MB INCREASE TO 40 (55) KT BY THIS AFTERNOON AND WITH THE INCREASING PRESSURE GRADIENT...SOME OF THIS SHOULD MAKE IT TO NEAR THE SURFACE. HIGH CLOUDS WILL LIKELY LIMIT MIXING THOUGH...AND WE WOULD FEEL BETTER WITH A DUE SOUTH OR SW WIND...SO A WIND ADVRY IS NO SLAM DUNK...BUT WITH THE PRESSURE GRADIENT AND MIXING TO 925 MB WE WILL LIKELY SEE A FEW SITES MEET CRITERIA THIS AFTN INTO THE EVNG HOURS. THUS WE HAVE ISSUED A WIND ADVISORY. THE DRY LINE STILL LOOKS TO SET UP OVER THE WRN HI PLAINS TODAY AS THE UPPER LEVEL SYSTEM MOVES TOWARD THE REGION. SOME POSITIVE CAPE IS INDICATED NEAR THE DRY LINE...BUT CIN IS SIGNIFICANT AND WITH MUCH OF THE FORCING GOING INTO SODAK...CONVECTIVE POTENTIAL FOR THE NEB AREA LOOKS PRETTY LOW...AND ESPECIALLY ANYTHING THAT WOULD WORK INTO OUR FA. THUS HAVE REDUCED POPS TO SCHC FOR THIS EVNG IN THE NW. A LITTLE BETTER CHC OF SHOWERS/STORMS MAY ACTUALLY COME AFTER MIDNIGHT IN THE ERN FA AS BETTER MOISTURE INTERACTS WITH THE ADVANCING PAC CDFNT AS IT MOVES THROUGH THE AREA. WILL CONT SOME CHC POPS IN THE E AFTER MIDNIGHT FOR THIS. THE SYSTEM SHOULD BE CLEAR OF THE FA BY TUES MRNG WITH ANOTHER WARM AND DRY DAY EXPECTED FOR TUE/WED. THE SURFACE FNT STILL LOOKS TO HANG UP OVER MO/KS ON TUE/WED AND THIS WILL START TO RETREAT NWD WED NIGHT AND INTO THE DAY ON THU (ALTHOUGH I HAVE MY DOUBTS THAT IT WILL ACTUALLY MAKE IT INTO NEB). AS THE LOW LEVEL WAA INCREASES AHEAD OF A SHRTWV PROGGED FOR THU NIGHT SOME MOISTURE WILL LIKELY WORK AROUND THE FNT AND INTO CNTRL NEB BY LATE THU WHICH SHOULD ALLOW FOR A CHANCE OF SHOWERS/STORMS LATE THU...THU NIGHT AND INTO FRI. SIGNIFICANT DIFFERENCES THEN DEVELOP BETWEEN THE GFS AND EC FOR NEXT WEEKEND AND NO CHANGES WERE MADE PAST FRI. BOUSTEAD FIRE WEATHER... IN THE POST FRONT AIRMASS ON TUES THE AIR MASS IS EXPECTED TO DRY OUT SIGNIFICANTLY. DEEP MIXING TO AROUND 850 MB OR HIGHER WILL LEAD TO DEWPOINTS FALLING THROUGH A GOOD PART OF THE DAY IN THE CNTRL AND WRN CWA. DESPITE THE FRONT MOVING THROUGH...TEMPERATURES WITH THE MIXING ON TUES WILL LIKELY CLIMB BACK INTO THE MID AND EVEN SOME UPPER 70S. THIS WILL CREATE SEVERAL HOURS OF RH BELOW 20 PERCENT DURING THE AFTN ON TUES. WITH STRONGLY UNIDIRECTIONAL FLOW AND A DECENT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE SURFACE LOW OVER SD...SFC WINDS SHOULD BE SUSTAINED ABOVE 15 KT WITH GUSTS WELL OVER 25 KT. THIS ALL SHOULD COMBINED FOR A DANGEROUS FIRE WX DAY...ALTHOUGH WE ARE STARTING TO GREEN UP NICELY AROUND THE AREA...AND THUS HAVE ISSUED A FIRE WEATHER WATCH FOR TUES FOR A LARGE PART OF THE AREA. BOUSTEAD/MAYES && .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ011-012-015>018-030>034-042>045-050>053- 065>067-078-088-089. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 7 PM CDT THIS EVENING FOR NEZ015-033-043-044-050-051-065-078. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM CDT THIS EVENING FOR NEZ011-012-016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ043-055. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
342 AM CDT MON MAR 26 2012 .DISCUSSION... MAIN CONCERN OVER THE NEXT 30 HOURS IS THE POTENT UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. THIS IS PROGGED TO TAKE A TRACK NEWD TODAY AND MOVE THROUGH THE NORTHERN PLAINS TONIGHT AND TUE. AHEAD OF THE STRONG SYSTEM LOW LEVEL WAA IS CURRENTLY TAKING PLACE ACROSS THE REGION. MODELS SEEM TO HAVE A HIGH BIAS WITH THE MOISTURE ATTM...AND THUS A LITTLE BULLISH ON THE CONVECTIVE POTENTIAL FOR THE REST OF THE NIGHT. LATEST RUC ANALYSIS DOES INDC AROUND 500-1000 J/KG OF MUCAPE OVER THE WRN CWA...BUT POINT FORECAST SOUNDINGS INDC THIS MOISTURE IS RATHER SHALLOW AROUND 850 MB AND THERE IS A GOOD DEAL OF CIN HOLDING BACK THE CONVECTION. WE FEEL THIS TREND WILL CONT TONIGHT...BUT WILL MAINTAIN A SLIGHT CHANCE POPS B/W 12-15Z OVER THE CNTRL AND SERN CWA FOR ANYTHING ISO THAT MAY DEVELOP. OTHERWISE ANOTHER WINDY AND WARM DAY IS IN STORE FOR THE FA. WINDS AT 925 (850) MB INCREASE TO 40 (55) KT BY THIS AFTERNOON AND WITH THE INCREASING PRESSURE GRADIENT...SOME OF THIS SHOULD MAKE IT TO NEAR THE SURFACE. HIGH CLOUDS WILL LIKELY LIMIT MIXING THOUGH...AND WE WOULD FEEL BETTER WITH A DUE SOUTH OR SW WIND...SO A WIND ADVRY IS NO SLAM DUNK...BUT WITH THE PRESSURE GRADIENT AND MIXING TO 925 MB WE WILL LIKELY SEE A FEW SITES MEET CRITERIA THIS AFTN INTO THE EVNG HOURS. THUS WE HAVE ISSUED A WIND ADVISORY. THE DRY LINE STILL LOOKS TO SET UP OVER THE WRN HI PLAINS TODAY AS THE UPPER LEVEL SYSTEM MOVES TOWARD THE REGION. SOME POSITIVE CAPE IS INDICATED NEAR THE DRY LINE...BUT CIN IS SIGNIFICANT AND WITH MUCH OF THE FORCING GOING INTO SODAK...CONVECTIVE POTENTIAL FOR THE NEB AREA LOOKS PRETTY LOW...AND ESPECIALLY ANYTHING THAT WOULD WORK INTO OUR FA. THUS HAVE REDUCED POPS TO SCHC FOR THIS EVNG IN THE NW. A LITTLE BETTER CHC OF SHOWERS/STORMS MAY ACTUALLY COME AFTER MIDNIGHT IN THE ERN FA AS BETTER MOISTURE INTERACTS WITH THE ADVANCING PAC CDFNT AS IT MOVES THROUGH THE AREA. WILL CONT SOME CHC POPS IN THE E AFTER MIDNIGHT FOR THIS. THE SYSTEM SHOULD BE CLEAR OF THE FA BY TUES MRNG WITH ANOTHER WARM AND DRY DAY EXPECTED FOR TUE/WED. THE SURFACE FNT STILL LOOKS TO HANG UP OVER MO/KS ON TUE/WED AND THIS WILL START TO RETREAT NWD WED NIGHT AND INTO THE DAY ON THU (ALTHOUGH I HAVE MY DOUBTS THAT IT WILL ACTUALLY MAKE IT INTO NEB). AS THE LOW LEVEL WAA INCREASES AHEAD OF A SHRTWV PROGGED FOR THU NIGHT SOME MOISTURE WILL LIKELY WORK AROUND THE FNT AND INTO CNTRL NEB BY LATE THU WHICH SHOULD ALLOW FOR A CHANCE OF SHOWERS/STORMS LATE THU...THU NIGHT AND INTO FRI. SIGNIFICANT DIFFERENCES THEN DEVELOP BETWEEN THE GFS AND EC FOR NEXT WEEKEND AND NO CHANGES WERE MADE PAST FRI. BOUSTEAD && FIRE WEATHER... IN THE POST FRONT AIRMASS ON TUES THE AIR MASS IS EXPECTED TO DRY OUT SIGNIFICANTLY. DEEP MIXING TO AROUND 850 MB OR HIGHER WILL LEAD TO DEWPOINTS FALLING THROUGH A GOOD PART OF THE DAY IN THE CNTRL AND WRN CWA. DESPITE THE FRONT MOVING THROUGH...TEMPERATURES WITH THE MIXING ON TUES WILL LIKELY CLIMB BACK INTO THE MID AND EVEN SOME UPPER 70S. THIS WILL CREATE SEVERAL HOURS OF RH BELOW 20 PERCENT DURING THE AFTN ON TUES. WITH STRONGLY UNIDIRECTIONAL FLOW AND A DECENT PRESSURE GRADIENT ON THE SOUTH SIDE OF THE SURFACE LOW OVER SD...SFC WINDS SHOULD BE SUSTAINED ABOVE 15 KT WITH GUSTS WELL OVER 25 KT. THIS ALL SHOULD COMBINED FOR A DANGEROUS FIRE WX DAY. ALTHOUGH WE ARE STARTING TO GREEN UP NICELY AROUND THE ARE AND THUS HAVE ISSUED A FIRE WEATHER WATCH FOR TUES FOR A LARGE PART OF THE AREA. MAYES && .AVIATION... 06Z TAFS FOR KOFK...KOMA AND KLNK. WARM ADVECTION REST OF TONIGHT WILL BRING OCCASIONAL VFR CIGS...GENERALLY AT OR ABOVE 5K AGL FT...TO TAF SITES. ALTHOUGH IT APPEARS MVFR CIGS/VSBYS SHOULD NOT OCCUR. THERE IS AN SLIGHT CHANCE A SHOWER/TSTM COULD DEVELOP IN WARM ADVECTION ZONE FM CNTRL INTO NCNTRL NEBRASKA WHICH COULD DRIFT ACROSS ERN NEBR LATE TONIGHT/MON MORNING. HOWEVER...COVERAGE/CHANCE IS TOO SMALL TO INCLUDE IN TAF FORECAST. SSE SURFACE WINDS WILL DRAMATICALLY INCREASE BY MONDAY AFTERNOON WITH SUSTAINED WINDS LIKELY AT LEAST IN 20-25KT RANGE. A STRONG UPPER SYSTEM LIFTING NE ACROSS THE DAKOTAS LATE MONDAY WILL SEND A COLD FRONT TOWARD CENTRAL NEBRASKA WITH AN ISOLD SHOWER/TSTM APPROACHING NERN NEBRASKA TOWARD 27/06Z. CHERMOK && .OAX WATCHES/WARNINGS/ADVISORIES... NE...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NEZ011-012-015>018-030>034-042>045-050>053- 065>067-078-088-089. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 7 PM CDT THIS EVENING FOR NEZ015-033-043-044-050-051-065-078. WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM CDT THIS EVENING FOR NEZ011-012-016>018-030>032-042. IA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR IAZ043-055. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1155 PM CDT SUN MAR 25 2012 .AVIATION...06Z TAF. MID TO HIGH LEVEL CLOUDS WILL SETTLE ACROSS THE TERMINAL OVERNIGHT. MOISTURE AXIS IS WEST OF KGRI WHERE PATCHY FOG IS POSSIBLE...OTHERWISE AN INCREASING LLVL JET OVERNIGHT MAY LEAD TO SOME HIT OR MISS CONVECTION WITH KGRI ON THE PERIPHERY OF THE POTENTIAL. SOUTHERLY WINDS WILL BE ON THE INCREASE MONDAY WITH WIND SPEEDS IN THE AFTN AVERAGING 25 TO 30KTS WITH GUSTS OVER 40KTS. && .PREV DISCUSSION... /ISSUED 1005 PM CDT SUN MAR 25 2012/ UPDATE...MOISTURE AXIS IS ALIGNING ACROSS OUR WESTERN CWA ATTM AND HRRR MODEL SUGGESTS POTENTIAL FOR SOME REDUCED VSBYS IN FOG ALONG MOISTURE AXIS AND HAVE ADDED IN SOME PATCHY FOG TOWARD MORNING. ALSO...INCREASING LLVL JET OVER MOISTURE AXIS AND DECENT AREA OF THETA E ADVECTION ALIGNS ACROSS OUR EASTERN CWA OVERNIGHT. CANNOT COMPLETELY RULE OUT A STORM OR TWO IN THIS AREA AND INCLUDED SOME LOW POPS FOR TONIGHT. PREV DISCUSSION... /ISSUED 448 PM CDT SUN MAR 25 2012/ SHORT TERM...TONIGHT AND TOMORROW. PRIMARY FORECAST CONCERNS LIE WITH PRECIPITATION CHANCES AND WINDS. UPPER AIR PROFILER AND SATELLITE DATA SHOW THE CENTRAL PLAINS REMAINING UNDER THE INFLUENCE OF A RIDGE AXIS...SANDWICHED BETWEEN LOW PRESSURE SYSTEMS LOCATED OVER THE CAROLINAS AND JUST OFF THE SOCAL COAST. LOW LEVEL STRATUS WHICH WAS PUSHING SOUTH THIS MORNING MADE IT IN TO JUST ABOUT I-80...BEFORE THE LOW LEVEL WINDS STARTED TRANSITIONING FROM THE NORTH TO MORE TO THE EAST. TOOK A LITTLE BIT...BUT THE SFC RIDGE AXIS FINALLY SHIFTED OFF TO THE EAST OF THE CWA...AND WITH LOW PRESSURE OVER THE ROCKIES...WINDS ACROSS THE ENTIRE CWA EVENTUALLY SWITCHED OVER TO THE S/SE. BETWEEN THIS MORNINGS CLOUD COVER NOT ERODING UNTIL LATE MORNING AND ANOTHER BATCH OF LOW/MID LEVEL CLOUDS AFFECTING THE NWRN CORNER OF THE CWA...TEMPS THIS AFTERNOON HAVE ONLY REACHED INTO THE MID 60S TO LOW 70S...VS THE MID/UPPER 70S ELSEWHERE ACROSS THE CWA. LOOKING TO THIS EVENING AND OVERNIGHT...KEPT THE FORECAST DRY...BUT WILL STATE THAT CONFIDENCE IS NOT HIGH...ESP IN THE NORTHEAST/EASTERN QUARTER OR SO OF THE CWA. MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH THE DEVELOPMENT OF A 40-50KT SWRLY LLJ TONIGHT...WHICH NOSES INTO...AND EVENTUALLY THROUGH THE CWA BY 12Z MONDAY. ACCOMPANYING THE NOSE OF THE LLJ IS A SURGE OF INCREASED WARM AIR/THETAE ADVECTION...MAINLY AFFECTING THE NERN HALF OF THE CWA BETWEEN 06-12Z. REALLY DEBATED THROWING SOME SMALL POPS IN...BUT ANOTHER THING THAT THE MODELS ARE IN GOOD AGREEMENT ON IS THE PRESENCE OF CAPPING...SHOWING 700MB TEMPS RANGING ANYWHERE FROM 5-9 DEG C DEPENDING ON THE MODEL. THE CAPPING IS A BIT WEAKER ALONG THAT NE/ERN FRINGE OF THE CWA...AND WHILE THE GFS DEVELOPS PRECIP THERE ISNT MUCH SUPPORT FROM OTHER MODELS WITH THERE BEING ENOUGH FORCING TO BREAK THROUGH THAT CAP. WITH CONTINUED S/SERN FLOW OVERNIGHT /WITH SPEEDS HIGHER THAN LAST FEW NIGHTS/...EXPECTING LOW TEMPS TO BE WARMER...AND FORECAST LOWS SIT IN THE LOWER/MID 50S. AS WE GET INTO TOMORROW...THE MAIN FOCUS TURNS TO WINDS...THOUGH PRECIPITATION CHANCES REMAIN FOR LATE AFTERNOON. THE UPPER LEVEL PATTERN SHOWS THE MAIN RIDGE AXIS SLIDING OFF TO THE EAST AS A DISTURBANCE MAKES ITS WAY TROUGH THE ROCKIES...LEAVING THE CWA WITH SWRLY FLOW. AS THIS DISTURBANCE MOVES CLOSER...EXPECTING TO SEE DEEPENING SFC LOW PRESSURE OVER THE NORTHERN ROCKIES WITH A TROUGH AXIS EXTENDING SOUTH THROUGH THE HIGH PLAINS. THIS WILL RESULT IN A TIGHTENING PRESSURE GRADIENT ACROSS THE CENTRAL PLAINS...AND INCREASING SRLY WINDS THROUGH THE DAY. WHILE MIXING POTENTIAL LOOKS TO ONLY REACH UPWARDS OF 850MB...THERE ARE ALSO INCREASED WINDS TO TAP INTO. DECIDED TO GO WITH A WIND ADV ACROSS THE CENTRAL AND WRN PORTIONS OF THE CWA...ALONG AND WEST OF HWY 281 DURING THE AFTERNOON HOURS. THE ERN FRINGE IS MORE ON THE MARGINAL SIDE...BUT WAS COMFORTABLE INCLUDING IT. EXPECTING TO SEE A BUMP UP IN TEMP...WITH HIGHS IN THE LOWER/MID 80S. AT THIS POINT COULD CREEP CLOSE TO RECORD HIGHS /MAINLY IN HASTINGS AND KEARNEY/...BUT SHOULD REMAIN BELOW. RECORDS ARE 86 AT BOTH HASTINGS AND KEARNEY IN 1989...AND 90 IN GRAND ISLAND IN 1907. THE POTENTIAL FOR THUNDERSTORMS BEGINS TO INCREASE LATE IN THE AFTERNOON...MAINLY ACROSS THE FAR WRN FRINGE OF THE CWA...AND DID KEEP THE LOW POPS IN. WHILE WE DO HAVE INCREASING INSTABILITY/LAPSE RATES AND THE DISTURBANCE IS SHIFTING CLOSER...MODELS REMAIN IN GOOD AGREEMENT KEEPING THINGS PRETTY CAPPED THROUGH THE AFTERNOON...SO WAS NOT GOING TO INCREASE POPS. LONG TERM...MONDAY EVENING THROUGH NEXT SUNDAY. VARIOUS CONCERNS DURING THIS 6-DAY TIME FRAME INCLUDE POSSIBLE...BUT CERTAINLY NOT LIKELY THUNDERSTORM CHANCES MONDAY NIGHT...POTENTIAL FIRE WEATHER ISSUES ON TUESDAY AFTERNOON...AND THEN ADDITIONAL...FAIRLY LOW CONFIDENCE THUNDERSTORM CHANCES IN THE THURSDAY-FRIDAY NIGHT TIME FRAME. WILL DISCUSS THESE ELEMENTS FIRST...AND CONCLUDE WITH SOME DISCUSSION ABOUT TEMPERATURES... STARTING OFF RIGHT AWAY MONDAY EVENING...THE MILLION DOLLAR QUESTION IS WHETHER ANY POTENTIALLY STRONG TO SEVERE STORMS WILL AFFECT THE CWA...AS A COMPACT BUT VIGOROUS NEGATIVELY TILTED MID LEVEL SHORTWAVE SWINGS FROM THE WY/NEB PANHANDLE AREA AT 00Z...TO ND BY 12Z TUESDAY MORNING. DUE TO THE TRACK OF THE WAVE...CLEARLY THE STRONGEST FORCING WILL REMAIN NORTH OF THE CWA. IN ADDITION...12Z NAM PLAN VIEW CINH FIELDS AND FORECAST SOUNDINGS INDICATE CONSIDERABLE CAPPING TO NEAR-SURFACE BASED PARCELS...AS EVIDENCED BY 700MB TEMPS INITIALLY IN THE 6-8C RANGE. ALTHOUGH THE 12Z GFS INSISTS ON STORMS AFFECTING AT LEAST THE WESTERN 1/3 OR SO OF THE CWA...THE LAST TWO NAM RUNS AND ALSO 12Z ECMWF SKIRT CONVECTION JUST NORTH OF THE CWA IN THE EVENING...AND THEN RE-FOCUSING EASTWARD ALONG AN AXIS FROM IA TO EASTERN KS AFTER MIDNIGHT ALONG THE ADVANCING 850MB FRONT AND WITHIN THE LOW LEVEL JET AXIS. ALTHOUGH SEVERE PARAMETERS ARE NOT GREAT...NAM/GFS GENERALLY AGREE ON ELEVATED CAPE IN THE 500-1000 J/KG RANGE DURING THE NIGHT...AND 0-6KM DEEP LAYER SHEAR AROUND 40KT. CERTAINLY THIS COULD SUPPORT STRONG TO MARGINALLY SEVERE STORMS...WITH HAIL TO QUARTER SIZE REALLY THE MAIN THREAT...BUT GIVEN LOW CONFIDENCE IN COVERAGE WILL KEEP POPS AT ONLY 20 PERCENT FOR NOW ACROSS THE NORTHWEST 2/3 OF THE CWA BEFORE MIDNIGHT...AND THE SOUTHEAST 1/3 LATER IN THE NIGHT. TUESDAY THROUGH WEDNESDAY NIGHT...KEPT IT DRY CWA-WIDE...AS QUASI-ZONAL FLOW TAKES HOLD OF THE CENTRAL PLAINS...DRIER LOW LEVEL AIR INVADES...AND THE PRIMARY SURFACE FRONT AND RESULTANT INSTABILITY AXIS HANGS UP ACROSS THE SOUTHERN 2/3 OF KANSAS. THAT BEING SAID...WILL HAVE TO KEEP AN EYE ON MAINLY NORTH CENTRAL KS ZONES IN THE TUES NIGHT AND WED NIGHT TIME FRAMES IN CASE ANY CONVECTION BRUSHES INTO THE CWA NEAR MODEST LOW LEVEL JETS FOCUSES FARTHER SOUTH. THE MAIN ISSUE WILL BE FIRE WEATHER CONCERNS FOR TUESDAY AFTERNOON BEHIND THE IMPRESSIVE DRYLINE PASSAGE. WITH DEWPOINTS DECREASING/MIXING DOWN INTO THE 20S TO LOW 30S AT BEST TUESDAY AFTERNOON...HAVE RELATIVE HUMIDITIES FALLING DOWN INTO THE 15-20 PERCENT RANGE MOST AREAS. ALTHOUGH THIS IS FORECAST INTO RED FLAG WARNING CRITERIA...THE STRONGEST SUSTAINED WIND SPEEDS AROUND 20 MPH OR HIGHER SHOULD FOCUS ACROSS THE NORTHERN 1/2 OF THE CWA IN CLOSER PROXIMITY TO THE DEPARTING SURFACE LOW...WITH LIGHTER WINDS PREVALENT NEAR AND SOUTH OF THE STATE LINE. DESPITE THE RECENT GREEN-UP...THE OFFICIAL VEGETATIVE FUEL STATUS IS STILL FAVORABLE FOR FIRE GROWTH...AND THUS WE COULD EASILY BE HEADING TOWARD A RED FLAG WARNING ESPECIALLY FOR MUCH OF NEB ZONES. ALTHOUGH CONFIDENCE IN THE DETAILS GETS PROGRESSIVELY LOWER WITH TIME...VARIOUS THUNDERSTORM CHANCES IN THE 20-50 PERCENT RANGE ENTER THE CWA IN THE THURSDAY THROUGH FRIDAY NIGHT TIME FRAME...AS AT LEAST TWO FAIRLY LOW AMPLITUDE SHORTWAVES PROGRESS THROUGH THE QUASI-ZONAL FLOW...AND INTERACT WITH AT LEAST MODEST INCREASING INSTABILITY AS A SURFACE RIDGE AXIS MOVES EAST AND INSTABILITY RETURNS. AS IT CURRENTLY STANDS...THE OVERALL BEST RISK FOR MEASURABLE RAINFALL IS THURSDAY NIGHT MAINLY IN THE EAST...BUT THESE CHANCES COULD EASILY MIGRATE AROUND OR CHANGE...AS THE ECMWF AND GFS START TO GET VERY OUT OF PHASE WITH TIMING OF WAVES. WITH DEEP LAYER SHEAR CURRENTLY LOOKING MODEST...CERTAINLY NO OBVIOUS SEVERE WEATHER THREATS IN THIS TIME FRAME...BUT ISOLATED SEVERE NOT OUT OF THE QUESTION. FOR SATURDAY- SUNDAY...LEFT DRY AS MODELS GENERALLY AGREE ON SHORTWAVE RIDGING. CONCLUDING WITH A BRIEF DISCUSSION ON TEMPS FROM TUESDAY THROUGH SUNDAY...KEPT HIGHS SIMILAR TO PREVIOUS FORECAST...WITH LOW-MID 70S ALL DAYS...BUT COULD FORESEE READINGS BY NEXT SUNDAY GETTING BOOSTED CLOSER TO 80 IF A RIDGE BUILDS AS ADVERTISED. REGARDING LOW TEMPS...DID MAKE SOME ADJUSTMENTS...GENERALLY NUDGING MANY AREAS DOWN 2-5 DEGREES FOR BOTH MON NIGHT AND TUES NIGHT AS DRIER AIR INVADES AND WINDS LIGHTEN. IN FACT...NOW HAVE MID-UPPER 30S ACROSS MUCH OF THE NORTHWEST CWA ON TUESDAY NIGHT. THAT BEING SAID...STILL NO LEGITIMATE FREEZING TEMPS IN SIGHT THROUGH THE NEXT WEEK. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY FROM 1 PM TO 7 PM CDT MONDAY FOR NEZ039-040-046- 047-060>062-072>075-082>085. KS...WIND ADVISORY FROM 1 PM TO 7 PM CDT MONDAY FOR KSZ005>007- 017>019. && $$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1046 PM EDT TUE MAR 27 2012 .SYNOPSIS... A LOW PRESSURE SYSTEM MOVING THROUGH THE UPPER GREAT LAKES AND SOUTHERN CANADA WILL SWING A WARM FRONT THROUGH THE REGION WEDNESDAY MORNING...FOLLOWED BY A COLD FRONT IN THE AFTERNOON. THESE FRONTS WILL BRING SOME RAIN SHOWERS AND POSSIBLE THUNDER TO THE AREA WEDNESDAY. SCATTERED RAIN OR SNOW SHOWERS WILL BE POSSIBLE ACROSS CENTRAL NEW YORK ON WEDNESDAY NIGHT...WITH SLOWLY IMPROVING CONDITIONS EXPECTED ON THURSDAY. HIGH PRESSURE WILL BUILD IN WITH FAIR SKIES ON THURSDAY NIGHT. && .NEAR TERM /THROUGH WEDNESDAY/... 1030 PM UPDATE...FORECAST UPDATED TO INCREASE POPS WEDNESDAY MORNING...AND EVEN INCLUDE MENTION OF THUNDER. WE REMAIN VERY DRY AT THE LOW LEVELS...BUT THE STRENGTH OF THE WARM AIR ADVECTION WITH THE INCOMING SYSTEM MUST BE RESPECTED. IN FACT...DESPITE 35 DEGREE DEWPOINT DEPRESSION FROM AN OBS SITE ON BRUCE PENINSULA AT THE SURFACE...ALOFT THERE IS ENOUGH MOISTURE AND EVEN INSTABILITY FOR A CLUSTER OF THUNDERSTORMS THAT HAS MANAGED TO DEVELOP. SURFACE-BASED LIFTED INDICES IN OUR SOUNDINGS 12Z-15Z OF COURSE ARE VERY POSITIVE. BUT A CLOSER LOOK AT THE LATEST SOUNDINGS REVEAL THAT ABOVE THE VERY STABLE NEAR SURFACE LAYER...THERE IS ACTUALLY A FAIR AMOUNT OF INSTABILITY. KELM NAM SOUNDING SEEN VIA BUFKIT FOR EXAMPLE MANAGES A FEW HUNDRED J/KG ELEVATED CAPE...AND PRECIPITABLE WATER CLIMBS ABOVE AN INCH. THE RAPID UPDATE HIGH RESOLUTION MODELS SUCH AS THE HRRR AND ARW ARE ALSO CATCHING ON TO THIS QUICKLY EVOLVING TREND...THAT SHOWERS AND EVEN THUNDER ARE BECOMING MORE PROBABLE IN THE MORNING. BRIEF WARM SECTOR THEN COMES IN BEHIND THE MORNING BATCH...ONLY FOR COLD FRONT TO THEN PASS THROUGH THE AREA FOR ADDITIONAL CHANCE OF SHOWERS AND THUNDER. WELL UPSTREAM...THUNDERSTORMS IN ILLINOIS ARE GIVING US A HINT OF THIS POTENTIAL. AS CAN BE EXPECTED WITH THE RADIATIONAL COOLING SITUATION UP TO NOW THIS EVENING...TEMPERATURES HAVE NEEDED TWEAKING TO KEEP UP WITH CURRENT CONDITIONS AND TRENDS. THICKENING HIGH CLOUDS AND INCREASING WARM AIR ADVECTION WILL ALLOW LOWS TO OCCUR BY AROUND MIDNIGHT OR SO...WITH HIGH CLOUDS AND WARM AIR ADVECTION HELPING TEMPERATURES TURN THE CORNER TO RISE FOR THE REMAINDER OF THE NIGHT. IF SHOWERS MOVE IN FAST ENOUGH...A COUPLE PLACES IN MOHAWK VALLEY...PARTICULARLY NORTHERN ONEIDA COUNTY COULD A LIGHT FREEZING RAIN THAT QUICKLY SWITCHES OVER TO PLAIN RAIN. HOWEVER...THIS IS NOT CONSIDERED VERY LIKELY AT THIS TIME...WITH MORE PROBABLE OUTCOMING BEING TEMPERATURES BREAKING ABOVE FREEZING BEFORE OR JUST AS SHOWERS ARRIVE. BIG GRADIENT IN TEMPERATURES WEDNESDAY...WITH SURGE OF WARM AIR CAPTURING MOST OF THE AREA...YET TRIPLE POINT PASSING CLOSE TO THE NORTHEASTERN ZONES AND ALSO STABLE LOW LEVEL AIR BEING PERHAPS A BIT HARDER TO SCOUR OUT. PARTIAL SUNSHINE BETWEEN BATCHES OF SHOWERS/THUNDER...WILL ALLOW TEMPERATURES IN WARM SECTOR FOR MOST OF THE AREA TO CLIMB INTO THE UPPER 50S TO MID 60S...YET CLOSER TO 50 IN THE MOHAWK VALLEY NORTHWARD. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... 2NDRY SURGE OF COOLER AIR WORKS SOUTH ON WED NGT...AS S/WV MOVS BY TO THE N. MDLS SHOW MOIST NW FLOW...SO CHC POPS FOR -SHRA/-SHSN OVRNGT. SLOW IMPROVMENT ON THU AS HIGH PRES TRIES TO BUILD IN BUT GUSTY NW WINDS SHUD PERSIST DURING THE DAY. WENT BELOW MOS GUIDANCE ON THU AS MOS MAXES WERE NOT SUPPORTED BY MDL 925 MB TEMPS...WHICH INFERRED MAXES THE L/M 40S. MAINLY SKC ON THU NGT AS SFC RDG AXIS MOVS INTO THE AREA. ON FRI LEANED TWDS THE 12Z GFS/00Z EURO...AND ONLY MENTIONED A SLGT CHC OF -SHRA ACRS FAR SW SXNS OF THE CWA LATE IN THE DAY. OTRW...IT APPEARS THAT THERE WILL BE PLENTY OF MID AND HI CLD SPREADING ACRS CNTRL AND SRN SXNS ON FRI. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... 440 PM UPDATE...LONG TERM PATTERN IS SOMEWHAT BUSY WITH QUICK SUCCESSION OF MID SCALE UPPER RIDGES AND WAVES. YET BECAUSE THESE UPPER FEATURES ARE NOT VERY BIG...THE FORECAST IS PRONE TO MODEL- TO-MODEL AND RUN-TO-RUN INCONSISTENCIES ON TIMING FOR EACH OF THEM. ALSO...WITH THE QUICK TIMING BETWEEN FEATURES...MOISTURE AVAILABILITY COULD BE AND ISSUE. THUS I DID NOT STRAY MUCH FROM HPC GUIDANCE...WHICH ITSELF WAS FAIRLY NON-COMMITTAL WITH SLIGHT TO LOW CHANCE POPS. ON A LARGER SCALE THOUGH...GFS/ECMWF AT LEAST HAVE COME INTO AGREEMENT ON NEAR NORMAL 500MB HEIGHTS EARLY IN THE WEEKEND...TRANSITIONING TO BRIEF PERIOD OF ABOVE NORMAL HEADING INTO MONDAY/TUESDAY. OUR FORECAST THUS ALSO TRENDS FROM NEAR NORMAL EARLY IN THE PERIOD...TO ROUGHLY 10 DEGREES ABOVE CLIMATOLOGY BY MONDAY/TUESDAY. ONE OTHER NOTE...NEW 12Z ECMWF HAS A COASTAL SURFACE LOW MOVING UP FROM THE MIDATLANTIC TO OFFSHORE THE NORTHEAST...WITH THE BACK PART OF ITS PRECIPITATION SHIELD ALONG WITH A MORE AMPLIFIED UPPER WAVE OVER OUR REGION ON SUNDAY. THIS IS A SIGNIFICANT DEPARTURE FROM THE 00Z ECMWF...AND IS STARKLY DIFFERENT FROM THE 12Z GFS...SO NOT PUTTING TOO MUCH STOCK INTO THAT SCENARIO AT THIS TIME. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... 730 PM UPDATE... IN GENERAL VFR CONDITIONS EXPECTED THROUGH TAF PERIOD. SFC LOW PRES MOVING THROUGH THE UPPER GREAT LAKES INTO SOUTHERN ONTARIO WILL BRING A WARM FRONT NEAR THE REGION LATE WED MORNING. MID/HIGH LEVEL CLOUDS WILL INCREASE OVERNIGHT WITH CIGS DROPPING TO 5K FT AROUND 11Z IN NY. SYSTEM LACKS MOISTURE AND IS MOVING INTO A VERY DRY AIRMASS THEREFORE ONLY INCLUDED PROB30 FOR MVFR RAIN SHOWERS AT KRME/KSYR BETWEEN 14Z TO 18Z. CIGS AT KRME COULD FALL TO MVFR WITH ANY MIDDAY SHOWERS. FOR THE AFTN AT KRME/KSYR PUT PREDOMINANT SHOWERS BUT CONFIDENCE NOT HIGH. NOT EXPECTING MVFR WITH THE SHOWERS. A BETTER CHANCE FOR SHOWERS EARLY EVENING AFTER 00Z. LIGHT AND VARIABLE WINDS BECOMING E/SE OVERNIGHT AT 5-10 KNOTS. LOW LEVEL WINDS SHEAR IS LIKELY LATE TONIGHT DUE TO SHARP INVERSION WITH STRONG SPEED/DIRECTIONAL SHEAR. WINDS AT 2K FT BY 06Z WILL BE 22035KT. SFC WINDS BECOMING S/SW AFTER SUNRISE AROUND 10 KNOTS. WINDS SHIFT TO WEST IN THE AFTN AT 12G20KTS. .OUTLOOK... WED NIGHT TO THU...CHC MVFR IN -SHRA...MIXED WITH -SHSN AT TIMES LATE WEDNESDAY NIGHT AND THURSDAY MORNING. THURSDAY AFTN TO FRIDAY NIGHT...VFR. SAT...CHC MVFR IN -SHRA...MOSTLY FOR KAVP. SAT NGT...VFR. SUNDAY...CHC MVFR IN -SHRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...MDP SHORT TERM... LONG TERM...MDP AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1045 PM EDT TUE MAR 27 2012 .SYNOPSIS... A MOSTLY CLEAR EVENING SKY WILL GIVE WAY TO INCREASING HIGH CLOUDS OVERNIGHT. A LOW PRESSURE SYSTEM MOVING THROUGH THE UPPER GREAT LAKES AND SOUTHERN CANADA WILL SWING A WARM FRONT THROUGH THE REGION WEDNESDAY MORNING...FOLLOWED BY A COLD FRONT IN THE AFTERNOON. THESE FRONTS WILL BRING SCATTERED RAIN SHOWERS TO THE AREA WEDNESDAY. SCATTERED RAIN OR SNOW SHOWERS WILL BE POSSIBLE ACROSS CENTRAL NEW YORK ON WEDNESDAY NIGHT...WITH SLOWLY IMPROVING CONDITIONS EXPECTED ON THURSDAY. HIGH PRESSURE WILL BUILD IN WITH FAIR SKIES ON THURSDAY NIGHT. && .NEAR TERM /THROUGH WEDNESDAY/... 1030 PM UPDATE...FORECAST UPDATED TO INCREASE POPS WEDNESDAY MORNING...AND EVEN INCLUDE MENTION OF THUNDER. WE REMAIN VERY DRY AT THE LOW LEVELS...BUT THE STRENGTH OF THE WARM AIR ADVECTION WITH THE INCOMING SYSTEM MUST BE RESPECTED. IN FACT...DESPITE 35 DEGREE DEWPOINT DEPRESSION FROM AN OBS SITE ON BRUCE PENINSULA AT THE SURFACE...ALOFT THERE IS ENOUGH MOISTURE AND EVEN INSTABILITY FOR A CLUSTER OF THUNDERSTORMS THAT HAS MANAGED TO DEVELOP. SURFACE-BASED LIFTED INDICES IN OUR SOUNDINGS 12Z-15Z OF COURSE ARE VERY POSITIVE. BUT A CLOSER LOOK AT THE LATEST SOUNDINGS REVEAL THAT ABOVE THE VERY STABLE NEAR SURFACE LAYER...THERE IS ACTUALLY A FAIR AMOUNT OF INSTABILITY. KELM NAM SOUNDING SEEN VIA BUFKIT FOR EXAMPLE MANAGES A FEW HUNDRED J/KG ELEVATED CAPE...AND PRECIPITABLE WATER CLIMBS ABOVE AN INCH. THE RAPID UPDATE HIGH RESOLUTION MODELS SUCH AS THE HRRR AND ARW ARE ALSO CATCHING ON TO THIS QUICKLY EVOLVING TREND...THAT SHOWERS AND EVEN THUNDER ARE BECOMING MORE PROBABLE IN THE MORNING. BRIEF WARM SECTOR THEN COMES IN BEHIND THE MORNING BATCH...ONLY FOR COLD FRONT TO THEN PASS THROUGH THE AREA FOR ADDITIONAL CHANCE OF SHOWERS AND THUNDER. WELL UPSTREAM...THUNDERSTORMS IN ILLINOIS ARE GIVING US A HINT OF THIS POTENTIAL. AS CAN BE EXPECTED WITH THE RADIATIONAL COOLING SITUATION UP TO NOW THIS EVENING...TEMPERATURES HAVE NEEDED TWEAKING TO KEEP UP WITH CURRENT CONDITIONS AND TRENDS. THICKENING HIGH CLOUDS AND INCREASING WARM AIR ADVECTION WILL ALLOW LOWS TO OCCUR BY AROUND MIDNIGHT OR SO...WITH HIGH CLOUDS AND WARM AIR ADVECTION HELPING TEMPERATURES TURN THE CORNER TO RISE FOR THE REMAINDER OF THE NIGHT. IF SHOWERS MOVE IN FAST ENOUGH...A COUPLE PLACES IN MOHAWK VALLEY...PARTICULARLY NORTHERN ONEIDA COUNTY COULD A LIGHT FREEZING RAIN THAT QUICKLY SWITCHES OVER TO PLAIN RAIN. HOWEVER...THIS IS NOT CONSIDERED VERY LIKELY AT THIS TIME...WITH MORE PROBABLE OUTCOMING BEING TEMPERATURES BREAKING ABOVE FREEZING BEFORE OR JUST AS SHOWERS ARRIVE. BIG GRADIENT IN TEMPERATURES WEDNESDAY...WITH SURGE OF WARM AIR CAPTURING MOST OF THE AREA...YET TRIPLE POINT PASSING CLOSE TO THE NORTHEASTERN ZONES AND ALSO STABLE LOW LEVEL AIR BEING PERHAPS A BIT HARDER TO SCOUR OUT. PARTIAL SUNSHINE BETWEEN BATCHES OF SHOWERS/THUNDER...WILL ALLOW TEMPERATURES IN WARM SECTOR FOR MOST OF THE AREA TO CLIMB INTO THE UPPER 50S TO MID 60S...YET CLOSER TO 50 IN THE MOHAWK VALLEY NORTHWARD. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... 2NDRY SURGE OF COOLER AIR WORKS SOUTH ON WED NGT...AS S/WV MOVS BY TO THE N. MDLS SHOW MOIST NW FLOW...SO CHC POPS FOR -SHRA/-SHSN OVRNGT. SLOW IMPROVMENT ON THU AS HIGH PRES TRIES TO BUILD IN BUT GUSTY NW WINDS SHUD PERSIST DURING THE DAY. WENT BELOW MOS GUIDANCE ON THU AS MOS MAXES WERE NOT SUPPORTED BY MDL 925 MB TEMPS...WHICH INFERRED MAXES THE L/M 40S. MAINLY SKC ON THU NGT AS SFC RDG AXIS MOVS INTO THE AREA. ON FRI LEANED TWDS THE 12Z GFS/00Z EURO...AND ONLY MENTIONED A SLGT CHC OF -SHRA ACRS FAR SW SXNS OF THE CWA LATE IN THE DAY. OTRW...IT APPEARS THAT THERE WILL BE PLENTY OF MID AND HI CLD SPREADING ACRS CNTRL AND SRN SXNS ON FRI. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... 440 PM UPDATE...LONG TERM PATTERN IS SOMEWHAT BUSY WITH QUICK SUCCESSION OF MID SCALE UPPER RIDGES AND WAVES. YET BECAUSE THESE UPPER FEATURES ARE NOT VERY BIG...THE FORECAST IS PRONE TO MODEL- TO-MODEL AND RUN-TO-RUN INCONSISTENCIES ON TIMING FOR EACH OF THEM. ALSO...WITH THE QUICK TIMING BETWEEN FEATURES...MOISTURE AVAILABILITY COULD BE AND ISSUE. THUS I DID NOT STRAY MUCH FROM HPC GUIDANCE...WHICH ITSELF WAS FAIRLY NON-COMMITTAL WITH SLIGHT TO LOW CHANCE POPS. ON A LARGER SCALE THOUGH...GFS/ECMWF AT LEAST HAVE COME INTO AGREEMENT ON NEAR NORMAL 500MB HEIGHTS EARLY IN THE WEEKEND...TRANSITIONING TO BRIEF PERIOD OF ABOVE NORMAL HEADING INTO MONDAY/TUESDAY. OUR FORECAST THUS ALSO TRENDS FROM NEAR NORMAL EARLY IN THE PERIOD...TO ROUGHLY 10 DEGREES ABOVE CLIMATOLOGY BY MONDAY/TUESDAY. ONE OTHER NOTE...NEW 12Z ECMWF HAS A COASTAL SURFACE LOW MOVING UP FROM THE MIDATLANTIC TO OFFSHORE THE NORTHEAST...WITH THE BACK PART OF ITS PRECIPITATION SHIELD ALONG WITH A MORE AMPLIFIED UPPER WAVE OVER OUR REGION ON SUNDAY. THIS IS A SIGNIFICANT DEPARTURE FROM THE 00Z ECMWF...AND IS STARKLY DIFFERENT FROM THE 12Z GFS...SO NOT PUTTING TOO MUCH STOCK INTO THAT SCENARIO AT THIS TIME. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... 730 PM UPDATE... IN GENERAL VFR CONDITIONS EXPECTED THROUGH TAF PERIOD. SFC LOW PRES MOVING THROUGH THE UPPER GREAT LAKES INTO SOUTHERN ONTARIO WILL BRING A WARM FRONT NEAR THE REGION LATE WED MORNING. MID/HIGH LEVEL CLOUDS WILL INCREASE OVERNIGHT WITH CIGS DROPPING TO 5K FT AROUND 11Z IN NY. SYSTEM LACKS MOISTURE AND IS MOVING INTO A VERY DRY AIRMASS THEREFORE ONLY INCLUDED PROB30 FOR MVFR RAIN SHOWERS AT KRME/KSYR BETWEEN 14Z TO 18Z. CIGS AT KRME COULD FALL TO MVFR WITH ANY MIDDAY SHOWERS. FOR THE AFTN AT KRME/KSYR PUT PREDOMINANT SHOWERS BUT CONFIDENCE NOT HIGH. NOT EXPECTING MVFR WITH THE SHOWERS. A BETTER CHANCE FOR SHOWERS EARLY EVENING AFTER 00Z. LIGHT AND VARIABLE WINDS BECOMING E/SE OVERNIGHT AT 5-10 KNOTS. LOW LEVEL WINDS SHEAR IS LIKELY LATE TONIGHT DUE TO SHARP INVERSION WITH STRONG SPEED/DIRECTIONAL SHEAR. WINDS AT 2K FT BY 06Z WILL BE 22035KT. SFC WINDS BECOMING S/SW AFTER SUNRISE AROUND 10 KNOTS. WINDS SHIFT TO WEST IN THE AFTN AT 12G20KTS. .OUTLOOK... WED NIGHT TO THU...CHC MVFR IN -SHRA...MIXED WITH -SHSN AT TIMES LATE WEDNESDAY NIGHT AND THURSDAY MORNING. THURSDAY AFTN TO FRIDAY NIGHT...VFR. SAT...CHC MVFR IN -SHRA...MOSTLY FOR KAVP. SAT NGT...VFR. SUNDAY...CHC MVFR IN -SHRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...MDP SHORT TERM... LONG TERM...MDP AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
653 PM EDT MON MAR 26 2012 .SYNOPSIS... SURFACE HIGH PRESSURE NEAR HUDSON BAY WILL BUILD INTO THE NORTH COUNTRY THROUGH TUESDAY. THIS WILL RESULT IN MAINLY CLEAR SKIES TONIGHT WITH CHILLY TEMPERATURES. ON TUESDAY...PLENTY OF SUNSHINE IS ANTICIPATED WITH TEMPERATURES IN THE 30S TO NEAR 40...ALONG WITH NORTHWEST WINDS OF 10 TO 20 MPH. A WARM FRONT WILL PRODUCE INCREASING CLOUDS WITH SCATTERED RAIN AND SNOW SHOWERS BY WEDNESDAY MORNING. && .NEAR TERM /UNTIL 8 AM TUESDAY MORNING/... AS OF 653 PM EDT MONDAY...PREVIOUS FORECAST STILL IN GOOD SHAPE. HAVE UPDATED THE GRIDS WITH THE LATEST SURFACE OBSERVATIONS. VISIBLE SATELLITE LOOP AND SURFACE OBSERVATIONS SHOWING CLEAR SKIES ACROSS NORTHERN NEW YORK AND THE CHAMPLAIN VALLEY...WITH LOW CLOUDS LINGERING ACROSS EASTERN VERMONT. EXPECTING THE CLOUDS ACROSS EASTERN VERMONT TO BEGIN TO DISSIPATE AFTER SUNSET WITH THE LOSS OF DAYTIME SURFACE HEATING...AND WITH DRIER AIR CONTINUING TO MOVE INTO THE REGION OVERNIGHT AS DEW POINTS WILL CONTINUE TO FALL OVERNIGHT. EXPECTING GUSTY NORTHWEST WINDS TO STAY UP OVERNIGHT AS WELL...AS TIGHT SURFACE PRESSURE GRADIENT REMAINS OVER THE REGION. PREVIOUS DISCUSSION FROM 345 PM EDT MONDAY...BIG PICTURE SHOWS DEEP MID/UPPER LVL TROF ACRS THE NE CONUS WITH RIBBON OF SUBSIDENCE/DRY AIR ALOFT BUILDING INTO OUR REGION. MEANWHILE...SFC ANALYSIS SHOWS 1032MB HIGH PRES BUILDING INTO OUR CWA....WITH SFC DWPTS IN THE SINGLE DIGITS ABOVE/BLW ZERO THIS AFTN. THIS AIRMASS WL BE ACRS OUR FA ON TUES...ALONG WITH PLENTY OF SUNSHINE. FCST CHALLENGE TONIGHT WL BE TEMPS...FOLLOWED BY DWPTS/RH PARAMETERS ON TUES...ALONG WITH SFC WINDS. UPSTREAM MINS LAST NIGHT SHOW MANY TEMPS IN THE SINGLE DIGITS WITH A FEW BLW ZERO READINGS SOUTH OF HUDSON BAY...ASSOCIATED WITH 925MB TEMPS -20C. GIVEN SOME GRADIENT ACRS OUR CWA....LIMITED SNOW PACK...AND SLIGHTLY WARMER 925MB TEMPS...WL MENTION LOWS FROM 0F AT SLK/MTNS TO 5 TO 10F CENTRAL/NORTHERN VT TO 10 TO 15F CPV/SLV. RUC13 AND NAM12 RH PROFILES STILL SHOW SOME 975MB TO 800MB RH ACRS THE NEK/NORTHERN VT MTNS THRU 03Z...THEREFORE WL TRY TO SHOW SOME CLOUDS...BUT OTHERWISE MAINLY CLR SKIES TONIGHT...WITH NW WINDS OF 10 TO 20 WITH GUSTS TO 30 MPH UNTIL MTN...DECREASING TO 5 TO 15 MPH WITH GUSTS TO 20 MPH TWD MORNING. TUESDAY...SFC HIGH PRES CENTERED OVER THE OTTAWA VALLEY AT 12Z WL SHIFT INTO NORTHERN NY BY 15Z AND INTO THE CPV BY 18Z TUES...WITH A WEAKENING PRES GRADIENT. SOUNDINGS SHOW MIXED LAYER WINDS BTWN 15 AND 25 MPH THRU NOON...ESPECIALLY CENTRAL/EASTERN VT...BUT DECREASING AS GRADIENT SLACKENS DURING THE AFTN HRS TO 5 TO 15 MPH. AT VSF...SOUNDING SHOWS MIXED LAYER WINDS OF 25 TO 30 KNTS...THRU 16Z...HELPING TO PRODUCE SFC WIND GUSTS TO 30 MPH...DURING THE MORNING HRS. SOUNDINGS SHOW GOOD MIXING TO 900MB ON TUES AFTN...WHICH WL TRANSFER SOME VERY DRY AIR TO THE SFC. UPSTREAM OBS UNDER SFC HIGH PRES SHOWS DWPTS BTWN -9F AND +5F...COMBINED WITH ANTICIPATED HIGHS IN THE 30S ON TUES...RESULTS IN MIN RH VALUES BTWN 10% AND 18%...WITH LOWEST VALUES ACRS THE SLV/NORTHERN NY ZNS ON TUES AFTN. GIVEN DEEP DRY LAYER...EXPECT PLENTY OF SUNSHINE WITH TEMPS 5 TO 10 DEGREES BLW NORMAL. && .SHORT TERM /8 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 345 PM EDT MONDAY...PROGRESSIVE MID/UPPER LVL PATTERN WL DEVELOP ACRS THE NE CONUS...WITH CHANGEABLE WX ANTICIPATED. ON TUES NIGHT...COMBINATION OF RETURN SOUTHERLY FLW AND DEVELOPING TIGHT SW TO NE THERMAL GRADIENT WL MAKE FOR A DIFFICULT LOW TEMP FCST. GIVEN...VERY DRY AIR IN PLACE AND SFC DWPTS IN THE SINGLE DIGITS...FEEL TEMPS WL QUICKLY DROP IN THE EARLY HRS...THEN INCREASE AFT MIDNIGHT AS WINDS/CLOUDS INCREASE. THINKING LOWS WL RANGE FROM 5 TO 10F NEK TO 20 TO 25F SLV/CPV. GFS/NAM ARE HANDLING MOISTURE/LIFT PROFILES ASSOCIATED WITH WAA DIFFERENTLY AND THE ACCOMPANYING QPF. NAM IS MUCH MORE AGGRESSIVE WITH QPF FIELDS ACRS OUR CENTRAL/NORTHERN CWA...WITH AMOUNTS NEAR 0.25"...WHILE GFS IS A TRACK TO 0.10". GIVEN...VERY DRY AIRMASS IN PLACE AHEAD OF 5H VORT AND WAA LIFT...AND DEVELOPING SOUTHERLY FLW...WL TREND TWD THE DRIER GFS SOLUTION. WL MENTION CHC POPS TO LOW LIKELY POPS ACRS NNY INTO NORTHERN VT MTNS AFT 06Z WEDS...WITH SOME LIGHT SNOW ACCUMULATION POSSIBLE (TRACE TO 1"). INITIALLY THERMAL PROFILES SUPPORT ALL SNOW...AS 1000 TO 500MB THICKNESS VALUES ARE BLW 540 AND PROGGED 85H TEMPS ARE BTWN -2C AND -4C. BEST 850 TO 500MB RH AND 700 TO 500MB OMEGA LIFTS FROM SW TO NW ACRS OUR CWA BTWN 06Z AND 15Z WEDS. AFTER 15Z...BEST MOISTURE/LIFT IS ACRS OUR EXTREME NORTHERN ZNS...AS WARM ADVECTS INTO OUR CWA. LOCAL 4KM AND NAM SHOWS SOME LLVL DAMMING OF COLD AIR...ESPECIALLY NEK AND EXTREME NORTHERN SLV ON WEDS...CREATING A VERY TIGHT THERMAL GRADIENT. WITH CLRING SKIES PARTS OF THE SLV FROM GOUVERNEUR TO POTSDAM/CANTON WL WARM INTO THE L60S...WHILE NEAR MSS COULD STRUGGLE TO REACH 50F. ELSEWHERE...GIVEN SHARP 925MB THERMAL GRADIENT ACRS OUR CWA...TEMPS WL BE TRICKY...WL MENTION L/M50S CPV TO L/M40S NEK/MTNS OF VT. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 354 PM EDT MONDAY...GFS/ECMWF IN FAIRLY GOOD AGREEMENT ON THE OVERALL PATTERN FOR THURSDAY AND FRIDAY...WITH INCREASING DISAGREEMENT BEYOND FRIDAY. TEMPERATURES THROUGH THE EXTENDED ARE CLOSE TO NORMAL THROUGH FRIDAY...TRENDING ABOVE NORMAL BY THE WEEKEND. SYSTEM EXPECTED TO IMPACT THE REGION ON WEDNESDAY BEGINS TO EXIT NEW ENGLAND THURSDAY. MAINTAINED CHANCE PRECIPITATION PROBABILITIES FOR THURSDAY AFTERNOON...THOUGH HAVE GONE WITH SLIGHT CHANCE PRECIPITATION PROBABILITIES FOR THURSDAY AFTERNOON/EVENING ALONG EASTERN-FACING SLOPES WHERE UPSLOPE SHOWERS MAY CONTINUE TO LINGER. NORTHERLY FLOW THURSDAY NIGHT ALLOWS 850MB TEMPERATURES TO FALL INTO THE -8 TO -10C RANGE. HIGHS ON THURSDAY REACH INTO THE 40S WITH LOWS IN THE 20S TO AROUND 30 IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS. WEAK HIGH PRESSURE THEN BUILDS IN FOR FRIDAY WITH TEMPERATURES A COUPLE OF DEGREES COOLER THAN THURSDAY. FOR THE WEEKEND...DIFFERENCES EMERGE IN TIMING REGARDING A DEVELOPING LOW PRESSURE SYSTEM MOVING IN FROM THE SOUTHERN GREAT LAKES/OHIO VALLEY REGION. 12Z GFS TRACKS THE LOW FURTHER TO THE NORTH ON SATURDAY THAN THE 12Z ECMWF...AND IS ALSO MORE PROGRESSIVE THAN THE 12Z ECMWF. DIVERGENT SOLUTIONS CONTINUE INTO EARLY NEXT WEEK. HAVE OPTED TO NOT STRAY TOO FAR FROM CONTINUITY...SO HAVE KEPT MODERATING TEMPERATURES AND SLIGHT CHANCE PRECIPITATION PROBABILITIES GOING THROUGH THE REST OF THE EXTENDED. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... THROUGH 12Z TUESDAY...GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH 00Z WITH GUSTS TO 30 KNOTS EXPECTED...THEN TAPER OFF AND BE SUSTAINED IN THE 10 TO 20 KNOT RANGE. VFR CEILINGS EXIST THROUGH 00Z WITH JUST A FEW FLURRIES...BUT CLOUDS WILL QUICKLY DISSIPATE AROUND SUNSET. VFR CONDITIONS WILL EXIST THROUGH THE REMAINDER OF THE PERIOD. OUTLOOK 18Z TUESDAY THROUGH FRIDAY...VFR/MOSTLY CLR CONDITIONS TUESDAY WITH NW WINDS 10-20 MPH. LOW PRESSURE SYSTEM APPROACHING FROM THE GREAT LAKES REGION BRINGS A CHANCE OF LIGHT RAIN WEDNESDAY...WITH RAIN OR SNOW SHOWERS WEDNESDAY NIGHT INTO THURSDAY MORNING. PERIODS OF MVFR CONDITIONS WILL PREVAIL...WITH BRIEF IFR INTERVALS POSSIBLE. RIDGE OF SFC HIGH PRESSURE SHIFTING EWD FROM THE GREAT LAKES FOR FRIDAY SHOULD BRING LIGHT N-NW WINDS AND A RETURN TO DRIER/VFR CONDITIONS. && .FIRE WEATHER... AS OF 345 PM EDT MONDAY...CONDITIONS CONTINUE TO REMAIN FAVORABLE ON TUESDAY FOR POTENTIAL FIRE WEATHER CONCERNS. TEMPERATURES WILL START OUT COLD...BUT HUMIDITY RECOVERIES OVERNIGHT TONIGHT WILL BE FAIR. MIXING DEVELOPS EARLY AND WITH THE DRIEST PORTION OF THE CANADIAN HIGH MOVING DOWN OVER US...THE IDEA OF SHARPLY FALLING HUMIDITIES LATE MORNING AND AFTERNOON IS A GOOD BET. THIS WILL RESULT IN AFTERNOON RELATIVE HUMIDITIES FALLING INTO THE 12 TO 18 PERCENT RANGE. AS MENTIONED EARLIER...PRESSURE GRADIENT WILL BE STRONGEST IN THE MORNING AND THEN TAPER OFF IN THE AFTERNOON...NEVERTHELESS THE POTENTIAL FOR WIND GUSTS TO 25 MPH WILL EXIST...ESPECIALLY ACROSS VERMONT. FULL SUN WILL HELP DRY THE FINE FUELS...WHICH GOT A REPRIEVE FROM THE LIGHT SNOW/CLOUD COVER ON MONDAY. FORESTRY PERSONNEL INDICATE ABNORMALLY DRY FUELS OVERALL...THUS THE SITUATION WILL BE EXAMINED CLOSELY FOR POSSIBLY UPGRADE TO A RED FLAG WARNING GIVEN THE EXPECTED WEATHER CONDITIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR VTZ001>012-016>019. NY...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...TABER NEAR TERM...WGH/TABER SHORT TERM...TABER LONG TERM...LOCONTO AVIATION...BANACOS/EVENSON FIRE WEATHER...EVENSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
354 PM EDT MON MAR 26 2012 .SYNOPSIS... SURFACE HIGH PRESSURE NEAR HUDSON BAY WILL BUILD INTO THE NORTH COUNTRY THROUGH TUESDAY. THIS WILL RESULT IN MAINLY CLEAR SKIES TONIGHT WITH CHILLY TEMPERATURES. ON TUESDAY...PLENTY OF SUNSHINE IS ANTICIPATED WITH TEMPERATURES IN THE 30S TO NEAR 40...ALONG WITH NORTHWEST WINDS OF 10 TO 20 MPH. A WARM FRONT WILL PRODUCE INCREASING CLOUDS WITH SCATTERED RAIN AND SNOW SHOWERS BY WEDNESDAY MORNING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 345 PM EDT MONDAY...BIG PICTURE SHOWS DEEP MID/UPPER LVL TROF ACRS THE NE CONUS WITH RIBBON OF SUBSIDENCE/DRY AIR ALOFT BUILDING INTO OUR REGION. MEANWHILE...SFC ANALYSIS SHOWS 1032MB HIGH PRES BUILDING INTO OUR CWA....WITH SFC DWPTS IN THE SINGLE DIGITS ABOVE/BLW ZERO THIS AFTN. THIS AIRMASS WL BE ACRS OUR FA ON TUES...ALONG WITH PLENTY OF SUNSHINE. FCST CHALLENGE TONIGHT WL BE TEMPS...FOLLOWED BY DWPTS/RH PARAMETERS ON TUES...ALONG WITH SFC WINDS. UPSTREAM MINS LAST NIGHT SHOW MANY TEMPS IN THE SINGLE DIGITS WITH A FEW BLW ZERO READINGS SOUTH OF HUDSON BAY...ASSOCIATED WITH 925MB TEMPS -20C. GIVEN SOME GRADIENT ACRS OUR CWA....LIMITED SNOW PACK...AND SLIGHTLY WARMER 925MB TEMPS...WL MENTION LOWS FROM 0F AT SLK/MTNS TO 5 TO 10F CENTRAL/NORTHERN VT TO 10 TO 15F CPV/SLV. RUC13 AND NAM12 RH PROFILES STILL SHOW SOME 975MB TO 800MB RH ACRS THE NEK/NORTHERN VT MTNS THRU 03Z...THEREFORE WL TRY TO SHOW SOME CLOUDS...BUT OTHERWISE MAINLY CLR SKIES TONIGHT...WITH NW WINDS OF 10 TO 20 WITH GUSTS TO 30 MPH UNTIL MTN...DECREASING TO 5 TO 15 MPH WITH GUSTS TO 20 MPH TWD MORNING. TUESDAY...SFC HIGH PRES CENTERED OVER THE OTTAWA VALLEY AT 12Z WL SHIFT INTO NORTHERN NY BY 15Z AND INTO THE CPV BY 18Z TUES...WITH A WEAKENING PRES GRADIENT. SOUNDINGS SHOW MIXED LAYER WINDS BTWN 15 AND 25 MPH THRU NOON...ESPECIALLY CENTRAL/EASTERN VT...BUT DECREASING AS GRADIENT SLACKENS DURING THE AFTN HRS TO 5 TO 15 MPH. AT VSF...SOUNDING SHOWS MIXED LAYER WINDS OF 25 TO 30 KNTS...THRU 16Z...HELPING TO PRODUCE SFC WIND GUSTS TO 30 MPH...DURING THE MORNING HRS. SOUNDINGS SHOW GOOD MIXING TO 900MB ON TUES AFTN...WHICH WL TRANSFER SOME VERY DRY AIR TO THE SFC. UPSTREAM OBS UNDER SFC HIGH PRES SHOWS DWPTS BTWN -9F AND +5F...COMBINED WITH ANTICIPATED HIGHS IN THE 30S ON TUES...RESULTS IN MIN RH VALUES BTWN 10% AND 18%...WITH LOWEST VALUES ACRS THE SLV/NORTHERN NY ZNS ON TUES AFTN. GIVEN DEEP DRY LAYER...EXPECT PLENTY OF SUNSHINE WITH TEMPS 5 TO 10 DEGREES BLW NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... AS OF 345 PM EDT MONDAY...PROGRESSIVE MID/UPPER LVL PATTERN WL DEVELOP ACRS THE NE CONUS...WITH CHANGEABLE WX ANTICIPATED. ON TUES NIGHT...COMBINATION OF RETURN SOUTHERLY FLW AND DEVELOPING TIGHT SW TO NE THERMAL GRADIENT WL MAKE FOR A DIFFICULT LOW TEMP FCST. GIVEN...VERY DRY AIR IN PLACE AND SFC DWPTS IN THE SINGLE DIGITS...FEEL TEMPS WL QUICKLY DROP IN THE EARLY HRS...THEN INCREASE AFT MIDNIGHT AS WINDS/CLOUDS INCREASE. THINKING LOWS WL RANGE FROM 5 TO 10F NEK TO 20 TO 25F SLV/CPV. GFS/NAM ARE HANDLING MOISTURE/LIFT PROFILES ASSOCIATED WITH WAA DIFFERENTLY AND THE ACCOMPANYING QPF. NAM IS MUCH MORE AGGRESSIVE WITH QPF FIELDS ACRS OUR CENTRAL/NORTHERN CWA...WITH AMOUNTS NEAR 0.25"...WHILE GFS IS A TRACK TO 0.10". GIVEN...VERY DRY AIRMASS IN PLACE AHEAD OF 5H VORT AND WAA LIFT...AND DEVELOPING SOUTHERLY FLW...WL TREND TWD THE DRIER GFS SOLUTION. WL MENTION CHC POPS TO LOW LIKELY POPS ACRS NNY INTO NORTHERN VT MTNS AFT 06Z WEDS...WITH SOME LIGHT SNOW ACCUMULATION POSSIBLE (TRACE TO 1"). INITIALLY THERMAL PROFILES SUPPORT ALL SNOW...AS 1000 TO 500MB THICKNESS VALUES ARE BLW 540 AND PROGGED 85H TEMPS ARE BTWN -2C AND -4C. BEST 850 TO 500MB RH AND 700 TO 500MB OMEGA LIFTS FROM SW TO NW ACRS OUR CWA BTWN 06Z AND 15Z WEDS. AFTER 15Z...BEST MOISTURE/LIFT IS ACRS OUR EXTREME NORTHERN ZNS...AS WARM ADVECTS INTO OUR CWA. LOCAL 4KM AND NAM SHOWS SOME LLVL DAMMING OF COLD AIR...ESPECIALLY NEK AND EXTREME NORTHERN SLV ON WEDS...CREATING A VERY TIGHT THERMAL GRADIENT. WITH CLRING SKIES PARTS OF THE SLV FROM GOUVERNEUR TO POTSDAM/CANTON WL WARM INTO THE L60S...WHILE NEAR MSS COULD STRUGGLE TO REACH 50F. ELSEWHERE...GIVEN SHARP 925MB THERMAL GRADIENT ACRS OUR CWA...TEMPS WL BE TRICKY...WL MENTION L/M50S CPV TO L/M40S NEK/MTNS OF VT. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 354 PM EDT MONDAY...GFS/ECMWF IN FAIRLY GOOD AGREEMENT ON THE OVERALL PATTERN FOR THURSDAY AND FRIDAY...WITH INCREASING DISAGREEMENT BEYOND FRIDAY. TEMPERATURES THROUGH THE EXTENDED ARE CLOSE TO NORMAL THROUGH FRIDAY...TRENDING ABOVE NORMAL BY THE WEEKEND. SYSTEM EXPECTED TO IMPACT THE REGION ON WEDNESDAY BEGINS TO EXIT NEW ENGLAND THURSDAY. MAINTAINED CHANCE PRECIPITATION PROBABILITIES FOR THURSDAY AFTERNOON...THOUGH HAVE GONE WITH SLIGHT CHANCE PRECIPITATION PROBABILITIES FOR THURSDAY AFTERNOON/EVENING ALONG EASTERN-FACING SLOPES WHERE UPSLOPE SHOWERS MAY CONTINUE TO LINGER. NORTHERLY FLOW THURSDAY NIGHT ALLOWS 850MB TEMPERATURES TO FALL INTO THE -8 TO -10C RANGE. HIGHS ON THURSDAY REACH INTO THE 40S WITH LOWS IN THE 20S TO AROUND 30 IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS. WEAK HIGH PRESSURE THEN BUILDS IN FOR FRIDAY WITH TEMPERATURES A COUPLE OF DEGREES COOLER THAN THURSDAY. FOR THE WEEKEND...DIFFERENCES EMERGE IN TIMING REGARDING A DEVELOPING LOW PRESSURE SYSTEM MOVING IN FROM THE SOUTHERN GREAT LAKES/OHIO VALLEY REGION. 12Z GFS TRACKS THE LOW FURTHER TO THE NORTH ON SATURDAY THAN THE 12Z ECMWF...AND IS ALSO MORE PROGRESSIVE THAN THE 12Z ECMWF. DIVERGENT SOLUTIONS CONTINUE INTO EARLY NEXT WEEK. HAVE OPTED TO NOT STRAY TOO FAR FROM CONTINUITY...SO HAVE KEPT MODERATING TEMPERATURES AND SLIGHT CHANCE PRECIPITATION PROBABILITIES GOING THROUGH THE REST OF THE EXTENDED. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... THROUGH 12Z TUESDAY...GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH 00Z WITH GUSTS TO 30 KNOTS EXPECTED...THEN TAPER OFF AND BE SUSTAINED IN THE 10 TO 20 KNOT RANGE. VFR CEILINGS EXIST THROUGH 00Z WITH JUST A FEW FLURRIES...BUT CLOUDS WILL QUICKLY DISSIPATE AROUND SUNSET. VFR CONDITIONS WILL EXIST THROUGH THE REMAINDER OF THE PERIOD. OUTLOOK 18Z TUESDAY THROUGH FRIDAY...VFR/MOSTLY CLR CONDITIONS TUESDAY WITH NW WINDS 10-20 MPH. LOW PRESSURE SYSTEM APPROACHING FROM THE GREAT LAKES REGION BRINGS A CHANCE OF LIGHT RAIN WEDNESDAY...WITH RAIN OR SNOW SHOWERS WEDNESDAY NIGHT INTO THURSDAY MORNING. PERIODS OF MVFR CONDITIONS WILL PREVAIL...WITH BRIEF IFR INTERVALS POSSIBLE. RIDGE OF SFC HIGH PRESSURE SHIFTING EWD FROM THE GREAT LAKES FOR FRIDAY SHOULD BRING LIGHT N-NW WINDS AND A RETURN TO DRIER/VFR CONDITIONS. && .FIRE WEATHER... AS OF 345 PM EDT MONDAY...CONDITIONS CONTINUE TO REMAIN FAVORABLE ON TUESDAY FOR POTENTIAL FIRE WEATHER CONCERNS. TEMPERATURES WILL START OUT COLD...BUT HUMIDITY RECOVERIES OVERNIGHT TONIGHT WILL BE FAIR. MIXING DEVELOPS EARLY AND WITH THE DRIEST PORTION OF THE CANADIAN HIGH MOVING DOWN OVER US...THE IDEA OF SHARPLY FALLING HUMIDITIES LATE MORNING AND AFTERNOON IS A GOOD BET. THIS WILL RESULT IN AFTERNOON RELATIVE HUMIDITIES FALLING INTO THE 12 TO 18 PERCENT RANGE. AS MENTIONED EARLIER...PRESSURE GRADIENT WILL BE STRONGEST IN THE MORNING AND THEN TAPER OFF IN THE AFTERNOON...NEVERTHELESS THE POTENTIAL FOR WIND GUSTS TO 25 MPH WILL EXIST...ESPECIALLY ACROSS VERMONT. FULL SUN WILL HELP DRY THE FINE FUELS...WHICH GOT A REPRIEVE FROM THE LIGHT SNOW/CLOUD COVER ON MONDAY. FORESTRY PERSONNEL INDICATE ABNORMALLY DRY FUELS OVERALL...THUS THE SITUATION WILL BE EXAMINED CLOSELY FOR POSSIBLY UPGRADE TO A RED FLAG WARNING GIVEN THE EXPECTED WEATHER CONDITIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR VTZ001>012-016>019. NY...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...LOCONTO AVIATION...BANACOS/EVENSON FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
349 PM EDT MON MAR 26 2012 .SYNOPSIS... SURFACE HIGH PRESSURE NEAR HUDSON BAY WILL BUILD INTO THE NORTH COUNTRY THROUGH TUESDAY. THIS WILL RESULT IN MAINLY CLEAR SKIES TONIGHT WITH CHILLY TEMPERATURES. ON TUESDAY...PLENTY OF SUNSHINE IS ANTICIPATED WITH TEMPERATURES IN THE 30S TO NEAR 40...ALONG WITH NORTHWEST WINDS OF 10 TO 20 MPH. A WARM FRONT WILL PRODUCE INCREASING CLOUDS WITH SCATTERED RAIN AND SNOW SHOWERS BY WEDNESDAY MORNING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 345 PM EDT MONDAY...BIG PICTURE SHOWS DEEP MID/UPPER LVL TROF ACRS THE NE CONUS WITH RIBBON OF SUBSIDENCE/DRY AIR ALOFT BUILDING INTO OUR REGION. MEANWHILE...SFC ANALYSIS SHOWS 1032MB HIGH PRES BUILDING INTO OUR CWA....WITH SFC DWPTS IN THE SINGLE DIGITS ABOVE/BLW ZERO THIS AFTN. THIS AIRMASS WL BE ACRS OUR FA ON TUES...ALONG WITH PLENTY OF SUNSHINE. FCST CHALLENGE TONIGHT WL BE TEMPS...FOLLOWED BY DWPTS/RH PARAMETERS ON TUES...ALONG WITH SFC WINDS. UPSTREAM MINS LAST NIGHT SHOW MANY TEMPS IN THE SINGLE DIGITS WITH A FEW BLW ZERO READINGS SOUTH OF HUDSON BAY...ASSOCIATED WITH 925MB TEMPS -20C. GIVEN SOME GRADIENT ACRS OUR CWA....LIMITED SNOW PACK...AND SLIGHTLY WARMER 925MB TEMPS...WL MENTION LOWS FROM 0F AT SLK/MTNS TO 5 TO 10F CENTRAL/NORTHERN VT TO 10 TO 15F CPV/SLV. RUC13 AND NAM12 RH PROFILES STILL SHOW SOME 975MB TO 800MB RH ACRS THE NEK/NORTHERN VT MTNS THRU 03Z...THEREFORE WL TRY TO SHOW SOME CLOUDS...BUT OTHERWISE MAINLY CLR SKIES TONIGHT...WITH NW WINDS OF 10 TO 20 WITH GUSTS TO 30 MPH UNTIL MTN...DECREASING TO 5 TO 15 MPH WITH GUSTS TO 20 MPH TWD MORNING. TUESDAY...SFC HIGH PRES CENTERED OVER THE OTTAWA VALLEY AT 12Z WL SHIFT INTO NORTHERN NY BY 15Z AND INTO THE CPV BY 18Z TUES...WITH A WEAKENING PRES GRADIENT. SOUNDINGS SHOW MIXED LAYER WINDS BTWN 15 AND 25 MPH THRU NOON...ESPECIALLY CENTRAL/EASTERN VT...BUT DECREASING AS GRADIENT SLACKENS DURING THE AFTN HRS TO 5 TO 15 MPH. AT VSF...SOUNDING SHOWS MIXED LAYER WINDS OF 25 TO 30 KNTS...THRU 16Z...HELPING TO PRODUCE SFC WIND GUSTS TO 30 MPH...DURING THE MORNING HRS. SOUNDINGS SHOW GOOD MIXING TO 900MB ON TUES AFTN...WHICH WL TRANSFER SOME VERY DRY AIR TO THE SFC. UPSTREAM OBS UNDER SFC HIGH PRES SHOWS DWPTS BTWN -9F AND +5F...COMBINED WITH ANTICIPATED HIGHS IN THE 30S ON TUES...RESULTS IN MIN RH VALUES BTWN 10% AND 18%...WITH LOWEST VALUES ACRS THE SLV/NORTHERN NY ZNS ON TUES AFTN. GIVEN DEEP DRY LAYER...EXPECT PLENTY OF SUNSHINE WITH TEMPS 5 TO 10 DEGREES BLW NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... AS OF 345 PM EDT MONDAY...PROGRESSIVE MID/UPPER LVL PATTERN WL DEVELOP ACRS THE NE CONUS...WITH CHANGEABLE WX ANTICIPATED. ON TUES NIGHT...COMBINATION OF RETURN SOUTHERLY FLW AND DEVELOPING TIGHT SW TO NE THERMAL GRADIENT WL MAKE FOR A DIFFICULT LOW TEMP FCST. GIVEN...VERY DRY AIR IN PLACE AND SFC DWPTS IN THE SINGLE DIGITS...FEEL TEMPS WL QUICKLY DROP IN THE EARLY HRS...THEN INCREASE AFT MIDNIGHT AS WINDS/CLOUDS INCREASE. THINKING LOWS WL RANGE FROM 5 TO 10F NEK TO 20 TO 25F SLV/CPV. GFS/NAM ARE HANDLING MOISTURE/LIFT PROFILES ASSOCIATED WITH WAA DIFFERENTLY AND THE ACCOMPANYING QPF. NAM IS MUCH MORE AGGRESSIVE WITH QPF FIELDS ACRS OUR CENTRAL/NORTHERN CWA...WITH AMOUNTS NEAR 0.25"...WHILE GFS IS A TRACK TO 0.10". GIVEN...VERY DRY AIRMASS IN PLACE AHEAD OF 5H VORT AND WAA LIFT...AND DEVELOPING SOUTHERLY FLW...WL TREND TWD THE DRIER GFS SOLUTION. WL MENTION CHC POPS TO LOW LIKELY POPS ACRS NNY INTO NORTHERN VT MTNS AFT 06Z WEDS...WITH SOME LIGHT SNOW ACCUMULATION POSSIBLE (TRACE TO 1"). INITIALLY THERMAL PROFILES SUPPORT ALL SNOW...AS 1000 TO 500MB THICKNESS VALUES ARE BLW 540 AND PROGGED 85H TEMPS ARE BTWN -2C AND -4C. BEST 850 TO 500MB RH AND 700 TO 500MB OMEGA LIFTS FROM SW TO NW ACRS OUR CWA BTWN 06Z AND 15Z WEDS. AFTER 15Z...BEST MOISTURE/LIFT IS ACRS OUR EXTREME NORTHERN ZNS...AS WARM ADVECTS INTO OUR CWA. LOCAL 4KM AND NAM SHOWS SOME LLVL DAMMING OF COLD AIR...ESPECIALLY NEK AND EXTREME NORTHERN SLV ON WEDS...CREATING A VERY TIGHT THERMAL GRADIENT. WITH CLRING SKIES PARTS OF THE SLV FROM GOUVERNEUR TO POTSDAM/CANTON WL WARM INTO THE L60S...WHILE NEAR MSS COULD STRUGGLE TO REACH 50F. ELSEWHERE...GIVEN SHARP 925MB THERMAL GRADIENT ACRS OUR CWA...TEMPS WL BE TRICKY...WL MENTION L/M50S CPV TO L/M40S NEK/MTNS OF VT. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... AS OF 328 AM EDT MONDAY...A RELATIVELY QUIET EXTENDED FCST. WEAK SFC LOW IS EXPECTED TO TRACK FROM CENTRAL NY TO WELL SOUTH OF NEW ENGLAND DURING WEDNESDAY NIGHT. FEATURE IS ASSOCIATED WITH A MID- LEVEL SHORTWAVE TROUGH...WITH TROUGH AXIS POSITIVELY TILTED IN 00Z GFS AND MOVING EAST OF THE CT RIVER VALLEY BY 12Z THURSDAY. LIMITED MOISTURE AVAILABILITY AND QUICK MOVING SYSTEM...NOT EXPECTING A LOT OF PRECIPITATION ACROSS THE AREA...BUT WILL CARRY OVC SKIES, POPS 40-60 PERCENT, AND QPF VALUES OF 0.10-0.25" FOR WED NIGHT. WEAK SYSTEM MOVES AWAY THURSDAY WITH A FEW LINGERING RAIN OR MTN SNOW SHOWERS EARLY. GENERALLY TRENDING DRIER BY THURSDAY AFTN WITH PREVAILING N-NW FLOW AND SFC RIDGE BEGINNING TO BUILD EWD FROM THE GREAT LKS REGION. PATTERN BECOMES FAIRLY STAGNANT WITH DEEP-LAYER TROUGHING ACROSS THE CANADIAN MARITIMES. WILL BE GOING WITH A DRY FCST THURSDAY NIGHT THROUGH SATURDAY WITH UPSTREAM HIGH PRESSURE IN CONTROL. NEXT WEAK SHORTWAVE TROUGH EXPECTED TO CROSS NEAR OR SOUTH OF THE REGION SAT NIGHT INTO SUNDAY. WILL CARRY JUST A SLIGHT CHANCE OF A FEW SHOWERS ATTM FOR THIS FEATURE GIVEN TIMING UNCERTAINTIES. TEMPERATURES THRU THE PERIOD WILL BE NEAR SEASONAL NORMALS THROUGH FRIDAY WITH NLY WINDS INFLUENCED BY DOWNSTREAM DEEP-LAYER TROUGH. TEMPS THEN TRENDING SEVERAL DEGREES ABOVE NORMAL THIS WEEKEND. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... THROUGH 12Z TUESDAY...GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH 00Z WITH GUSTS TO 30 KNOTS EXPECTED...THEN TAPER OFF AND BE SUSTAINED IN THE 10 TO 20 KNOT RANGE. VFR CEILINGS EXIST THROUGH 00Z WITH JUST A FEW FLURRIES...BUT CLOUDS WILL QUICKLY DISSIPATE AROUND SUNSET. VFR CONDITIONS WILL EXIST THROUGH THE REMAINDER OF THE PERIOD. OUTLOOK 18Z TUESDAY THROUGH FRIDAY...VFR/MOSTLY CLR CONDITIONS TUESDAY WITH NW WINDS 10-20 MPH. LOW PRESSURE SYSTEM APPROACHING FROM THE GREAT LAKES REGION BRINGS A CHANCE OF LIGHT RAIN WEDNESDAY...WITH RAIN OR SNOW SHOWERS WEDNESDAY NIGHT INTO THURSDAY MORNING. PERIODS OF MVFR CONDITIONS WILL PREVAIL...WITH BRIEF IFR INTERVALS POSSIBLE. RIDGE OF SFC HIGH PRESSURE SHIFTING EWD FROM THE GREAT LAKES FOR FRIDAY SHOULD BRING LIGHT N-NW WINDS AND A RETURN TO DRIER/VFR CONDITIONS. && .FIRE WEATHER... AS OF 345 PM EDT MONDAY...CONDITIONS CONTINUE TO REMAIN FAVORABLE ON TUESDAY FOR POTENTIAL FIRE WEATHER CONCERNS. TEMPERATURES WILL START OUT COLD...BUT HUMIDITY RECOVERIES OVERNIGHT TONIGHT WILL BE FAIR. MIXING DEVELOPS EARLY AND WITH THE DRIEST PORTION OF THE CANADIAN HIGH MOVING DOWN OVER US...THE IDEA OF SHARPLY FALLING HUMIDITIES LATE MORNING AND AFTERNOON IS A GOOD BET. THIS WILL RESULT IN AFTERNOON RELATIVE HUMIDITIES FALLING INTO THE 12 TO 18 PERCENT RANGE. AS MENTIONED EARLIER...PRESSURE GRADIENT WILL BE STRONGEST IN THE MORNING AND THEN TAPER OFF IN THE AFTERNOON...NEVERTHELESS THE POTENTIAL FOR WIND GUSTS TO 25 MPH WILL EXIST...ESPECIALLY ACROSS VERMONT. FULL SUN WILL HELP DRY THE FINE FUELS...WHICH GOT A REPRIEVE FROM THE LIGHT SNOW/CLOUD COVER ON MONDAY. FORESTRY PERSONNEL INDICATE ABNORMALLY DRY FUELS OVERALL...THUS THE SITUATION WILL BE EXAMINED CLOSELY FOR POSSIBLY UPGRADE TO A RED FLAG WARNING GIVEN THE EXPECTED WEATHER CONDITIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR VTZ001>012-016>019. NY...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...BANACOS AVIATION...BANACOS/EVENSON FIRE WEATHER...EVENSON
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
629 AM EDT MON MAR 26 2012 .SYNOPSIS... DRIER AND COOLER CONDITIONS WILL SETTLE IN TODAY AND TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES. A BRIEF WARMING TREND WILL ENSUE DURING THE MIDDLE OF THIS WEEK...FOLLOWED BY A COLD FRONT ON THURSDAY. NEAR SEASONABLE WEATHER THEN EXPECTED INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM MONDAY...BKN-OVC LOW CLOUDS BLANKET THE AREA THIS MORNING...BUT THIS IS ONLY TEMPORARY AS DRIER AIR LURKING JUST WEST OF THE AREA PLUS CONTINUING ISENTROPIC DOWNGLIDE SHOULD ERODE MOST IF NOT ALL OF THE CLOUD COVER WITHIN THE NEXT 2-4 HOURS. NO SIGNIFICANT CHANGES WERE MADE FROM THE PREVIOUS FORECAST. DISCUSSION FROM 3 AM FOLLOWS... THE COLD UPPER LOW IS NOW WELL EAST OF CAPE HATTERAS AND MOVING OUT TO SEA. OUR MID-LEVEL TEMPERATURES HAVE WARMED CONSIDERABLY SINCE THE DEPARTURE OF THE LOW AND A MUCH DRIER AND MORE STABLE ATMOSPHERE IS EXPECTED TODAY INTO TONIGHT. SURFACE HIGH PRESSURE JUST NORTH OF THE GREAT LAKES WILL PUSH A SECONDARY COLD FRONT SOUTH AND THROUGH THE EASTERN CAROLINAS LATE THIS AFTERNOON. ALTHOUGH THERE SHOULDN`T BE ANY CLOUDS WITH THIS FEATURE...NORTH-NORTHEAST WINDS TONIGHT WILL BRING A MUCH COOLER AIRMASS INTO THE REGION THAN WE HAVE SEEN IN NEARLY TWO WEEKS. RESIDUAL LOW CLOUDS THIS MORNING SWIRLING AROUND THE BACKSIDE OF THE UPPER LOW EXTEND ACROSS THE EASTERN HALF OF NORTH CAROLINA. ISENTROPIC ANALYSIS REVEALS SINKING PARCEL TRAJECTORIES WHICH SHOULD GRADUALLY ERODE THESE CLOUDS FROM WEST TO EAST THROUGH THE EARLY MORNING HOURS. AFTER 14Z (10 AM) SUNSHINE SHOULD BE BREAKING OUT EVEN IN THE WILMINGTON AREA...WITH SUNNY SKIES EXPECTED EVERYWHERE DURING THE LATE MORNING AND AFTERNOON. HIGHS SHOULD REACH THE 75-80 TODAY... WARMEST IN THE SOUTH CAROLINA PEE DEE REGION AND COOLEST ALONG THE NC EAST-FACING BEACHES. LOWS TONIGHT SHOULD FALL TO 43-48...COOLEST IN INTERIOR SOUTHEAST NORTH CAROLINA AND WARMEST NEAR THE SANTEE RIVER. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...GUIDANCE CONTINUES TO INDICATE THAT TUESDAY WILL BE THE FIRST BELOW CLIMO DAY SINCE MARCH 11 AS A WEDGE OF HIGH PRESSURE BUILDS AGAINST THE APPALACHIAN RANGE. ALTHOUGH MODELS HAVE BACKED OFF ON STRENGTH OF THE WEDGE...NE FLOW AT THE SURFACE WILL KEEP TEMPS BELOW...TO WELL BELOW...SEASONABLE NORMS...WITH THE COOLEST READINGS BEING IN THE CAPE FEAR REGION WHERE NE WINDS ADVECT OFF THE COOL OCEAN. ALTHOUGH SOUNDINGS ARE QUITE DRY TUESDAY...NOTE THAT FREQUENTLY MOISTURE IS UNDER-MODELED IN WEDGE SCENARIOS SO WILL INCREASE CLOUD COVER MORE THAN SUGGESTED BY PROFILES. MIXING WILL LIKELY ONLY REACH TO BELOW 900MB...AND LOW LEVEL 1000-900MB THICKNESSES SUPPORT TEMPS ONLY IN THE LOWER 60S NEAR WILMINGTON...TO AROUND 70 ACROSS THE PEE DEE REGION OF SC. HIGH DRIFTS OVERHEAD TUESDAY NIGHT ALLOWING FOR DECOUPLING IN THE LOWER ATMOSPHERE...AND CLEAR SKY CONDITIONS WILL ALLOW FOR DECENT RADIATIONAL COOLING. THE FLY-IN-THE-OINTMENT...AS IT IS...IS WHETHER SOME SLIGHT LOW LEVEL WAA BEGINS OVERNIGHT AS HIGH DRIFTS OFFSHORE...OR WHETHER WE CAN STAY PERFECTLY CALM. NEARLY ALL THE FORECAST PROFILES SUGGEST WARMING IN THE LOW LEVELS FROM 06Z-12Z WEDNESDAY AS LIGHT SOUTHERLY FLOW DEVELOPS AROUND DEPARTING HIGH PRESSURE. BELIEVE IT WILL BE TOUGH FOR SUCH SIGNIFICANT WARMING AFTER MANY HOURS OF NOCTURNAL INVERSION DEVELOPMENT...BUT WILL NOT DROP MINS AS LOW AS MAV NUMBERS...AND OPT FOR LOW 40S AREA WIDE...WITH THE COLDEST SPOTS POTENTIALLY TOUCHING 39. BY WEDNESDAY THE HIGH HAS DRIFTED OFFSHORE AND WARM SOUTHERLY RETURN FLOW COMES BACK INTO THE CAROLINAS. MOSTLY SUNNY SKY CONDITIONS WILL HELP RAISE TEMPS BACK TO ABOVE CLIMO...MID 70S AWAY FROM THE COAST...AND CONTINUED SOUTHERLY FLOW AT NIGHT WILL KEEPS TEMPS FROM FALLING MUCH OUT OF THE MID 50S AT NIGHT. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY...MOST INTERESTING PART OF THE LONG TERM OCCURS LATE THURSDAY WITH A COLD FRONTAL PASSAGE...BEFORE COOL HIGH PRESSURE SETTLES IN TO THE WEEKEND. MODERATELY POTENT S/W TROUGH DIGS FROM THE GREAT LAKES THROUGH NEW ENGLAND THURSDAY...SUPPRESSING THE UPPER RIDGE AND DRIVING A COLD FRONT THROUGH THE CAROLINAS. STILL NOTING TIMING DIFFERENCES IN THE GUIDANCE...BUT FOR PERSISTENCE WILL CONTINUE TO FAVOR THE SLIGHTLY SLOWER ECMWF/CMC OVER THE GFS. NOT MUCH IN THE WAY OF MOISTURE RETURN AHEAD OF THIS...ALTHOUGH MID LEVEL THETA-E RIDGE DOES TRY TO ADVECT INTO OUR AREA JUST AHEAD OF FROPA...SO WILL CARRY SCHC POP FOR SHOWERS THURSDAY EVE/NIGHT. IF THE SLOWER SOLUTION COMES TRUE...850MB TEMPS RISE TO 11C WHICH SUPPORTS TEMPS AT OR ABOVE 80 MOST AREAS AWAY FROM THE BEACHES...AND THURSDAY WILL BE THE WARMEST DAY OF THE EXTENDED. IF...HOWEVER...A FASTER FROPA OCCURS...THIS WILL OBVIOUSLY CUT TEMPS BACK ESPECIALLY ACROSS THE NORTH...AND WOULD INCREASE THE LIKELIHOOD OF AFTN SHOWERS ALONG THE BOUNDARY. FOR NOW WILL STICK WITH THE SLOWER SOLUTION. COOL HIGH PRESSURE BUILDS ACROSS THE REGION FRI/SAT RETURNING THE AREA TO NEAR CLIMO TEMPS...POSSIBLY BELOW CLIMO WITH SOME NE FLOW ON FRIDAY. GFS/ECMWF THEN DIVERGE CONSIDERABLY ON EVOLUTION AND STRENGTH OF ANOTHER NORTHERN STREAM S/W DROPPING ACROSS THE MIDWEST RIDGE. GFS IS FASTER AND WEAKER...CONTINUING ITS TREND THIS YEAR...SO WILL BLEND ECMWF/GFS BUT WITH ADDITIONAL WEIGHT ON THE FORMER. THIS WILL BRING INCREASED CHANCES FOR RAIN THROUGH THE WKND AS LOW PRESSURE DEVELOPS NEAR THE OHIO VALLEY. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... AS OF 06Z...ALTHOUGH SHOWERS HAVE ENDED ACROSS SOUTH CAROLINA... RADAR AND THE LATEST HRRR MODEL SUGGEST IT`S NOT OVER FOR NORTH CAROLINA JUST YET. SHOWERS ROTATING SOUTHWARD ON THE BACK SIDE OF THE DEPARTING UPPER LEVEL LOW PRESSURE AREA WILL AFFECT THE ILM TERMINAL THROUGH 09Z...WITH EVEN A FEW LIGHT SHOWERS POSSIBLE IN THE LBT VICINITY THROUGH 0730Z OR SO. THERE IS SOME UNCERTAINTY WITH REGARDS TO CEILING HEIGHTS...MVFR SHOULD PREDOMINATE...BUT IFR IS NOT OUT OF THE QUESTION PARTICULARLY AFTER 08Z. AFTER DAYBREAK WINDS WILL PICK UP...GUSTING OVER 20 KTS BY MID MORNING. SKIES WILL BECOME NEARLY CLEAR AS THE UPPER LOW EXITS OFFSHORE. EXTENDED OUTLOOK...VFR MONDAY NIGHT THROUGH WEDNESDAY. POSSIBLE MORNING FOG THURSDAY AND FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM MONDAY...NORTH WINDS 15-20 KT HAVE DEVELOPED ACROSS THE COASTAL WATERS AS FORECAST. WE SHOULD BE IN THE 3-4 HOUR PERIOD OF STRONGEST WINDS CURRENTLY...WITH DIMINISHING WINDS LATE THIS MORNING INTO THE EARLY AFTERNOON HOURS. PREVIOUS DISCUSSION FROM 3 AM FOLLOWS... LOW PRESSURE HAS MOVED EAST OF THE NC OUTER BANKS AND WILL MOVE FARTHER OUT TO SEA TODAY. ATTENTION WILL TURN TO HIGH PRESSURE IN CANADA JUST NORTH OF THE GREAT LAKES THAT WILL BUILD SOUTH TOWARD THE CAROLINAS. AS THIS HIGH MOVES SOUTH IT WILL PUSH A DRY COLD FRONT THROUGH THE AREA LATE THIS AFTERNOON. NORTH- NORTHEAST WINDS WILL INCREASE BEHIND THIS FRONT...REACHING 15-20 KT BY LATE THIS EVENING AND CONTINUING OVERNIGHT. THERE IS SOME POTENTIAL SEAS COULD REACH 6 FEET IN THE WATERS NEAR FRYING PAN SHOALS DUE TO THEIR EXPOSED POSITION IN THIS WIND DIRECTION...BUT CONFIDENCE IS TOO LOW TO RAISE AN ADVISORY AT THIS TIME. ELSEWHERE SEAS 2-4 FEET TODAY SHOULD BUILD TO 3-5 FT TONIGHT AWAY FROM SHORE WITH THE INCREASED WIND SPEEDS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...NE SURGE ONGOING AT THE START OF THE PERIOD AROUND WEDGE OF HIGH PRESSURE. AT LEAST CAUTIONARY HEADLINES APPEAR LIKELY TO BE IN EFFECT TUESDAY MORNING WITH 15-20 KT WINDS CREATING 4-5 FT NE WIND WAVES CONTROLLING THE WAVE SPECTRUM. DURING TUESDAY...HIGH PRESSURE DRIFTS OVER THE WATERS SO WINDS/WAVES RAPIDLY DECREASE THROUGH THE DAY...WINDS BECOMING NEARLY CALM OVERNIGHT WHILE SEAS FALL TO 1-2 FT. GRADIENT INCREASES WEDNESDAY AS HIGH PRESSURE DRIFTS OFFSHORE AND A COLD FRONT APPROACHES FROM THE NW. THIS PUTS THE WATERS INTO A PRE FRONTAL REGIME...WITH SW WINDS INCREASING TO 15-20 KTS FORCING SEAS BACK UP TO 3-5 FT...AND CAUTIONARY HEADLINES MAY ONCE AGAIN BE NECESSARY. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 AM MONDAY...CAUTIONARY HEADLINES POSSIBLY ONGOING AT THE START OF THE PERIOD AS A COLD FRONT APPROACHES FROM THE NORTHWEST. SW WINDS OF 15-20 KTS WILL VEER AND WEAKEN THROUGH THE DAY...BECOMING NORTH AROUND 10 KTS THURSDAY NIGHT. SW WIND WAVES OF 3-5 FT EARLY THURSDAY FALL TO 2-3 FT BY FRIDAY MORNING. A PERIOD OF CONFUSED SEAS IS LIKELY THURSDAY EVE AS THE WAVE SPECTRUM FEATURES TWO DOMINANT WIND WAVES...ONE SLOWLY WEAKENING FROM THE SW...WHILE A BUILDING NE WIND WAVE DEVELOPS. N/NE WINDS LESS THAN 10 KTS FRIDAY KEEP SEAS ONLY AROUND 2 FT THROUGH THE DAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...TRA SHORT TERM...JDW LONG TERM...JDW AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
319 AM EDT MON MAR 26 2012 .SYNOPSIS... DRIER AND COOLER CONDITIONS WILL SETTLE IN TODAY AND TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES. A BRIEF WARMING TREND WILL ENSUE DURING THE MIDDLE OF THIS WEEK...FOLLOWED BY A COLD FRONT ON THURSDAY. NEAR SEASONABLE WEATHER THEN EXPECTED INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM MONDAY...THE COLD UPPER LOW IS NOW WELL EAST OF CAPE HATTERAS AND MOVING OUT TO SEA. OUR MID-LEVEL TEMPERATURES HAVE WARMED CONSIDERABLY SINCE THE DEPARTURE OF THE LOW AND A MUCH DRIER AND MORE STABLE ATMOSPHERE IS EXPECTED TODAY INTO TONIGHT. SURFACE HIGH PRESSURE JUST NORTH OF THE GREAT LAKES WILL PUSH A SECONDARY COLD FRONT SOUTH AND THROUGH THE EASTERN CAROLINAS LATE THIS AFTERNOON. ALTHOUGH THERE SHOULDN`T BE ANY CLOUDS WITH THIS FEATURE...NORTH-NORTHEAST WINDS TONIGHT WILL BRING A MUCH COOLER AIRMASS INTO THE REGION THAN WE HAVE SEEN IN NEARLY TWO WEEKS. RESIDUAL LOW CLOUDS THIS MORNING SWIRLING AROUND THE BACKSIDE OF THE UPPER LOW EXTEND ACROSS THE EASTERN HALF OF NORTH CAROLINA. ISENTROPIC ANALYSIS REVEALS SINKING PARCEL TRAJECTORIES WHICH SHOULD GRADUALLY ERODE THESE CLOUDS FROM WEST TO EAST THROUGH THE EARLY MORNING HOURS. AFTER 14Z (10 AM) SUNSHINE SHOULD BE BREAKING OUT EVEN IN THE WILMINGTON AREA...WITH SUNNY SKIES EXPECTED EVERYWHERE DURING THE LATE MORNING AND AFTERNOON. HIGHS SHOULD REACH THE 75-80 TODAY... WARMEST IN THE SOUTH CAROLINA PEE DEE REGION AND COOLEST ALONG THE NC EAST-FACING BEACHES. LOWS TONIGHT SHOULD FALL TO 43-48...COOLEST IN INTERIOR SOUTHEAST NORTH CAROLINA AND WARMEST NEAR THE SANTEE RIVER. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...GUIDANCE CONTINUES TO INDICATE THAT TUESDAY WILL BE THE FIRST BELOW CLIMO DAY SINCE MARCH 11 AS A WEDGE OF HIGH PRESSURE BUILDS AGAINST THE APPALACHIAN RANGE. ALTHOUGH MODELS HAVE BACKED OFF ON STRENGTH OF THE WEDGE...NE FLOW AT THE SURFACE WILL KEEP TEMPS BELOW...TO WELL BELOW...SEASONABLE NORMS...WITH THE COOLEST READINGS BEING IN THE CAPE FEAR REGION WHERE NE WINDS ADVECT OFF THE COOL OCEAN. ALTHOUGH SOUNDINGS ARE QUITE DRY TUESDAY...NOTE THAT FREQUENTLY MOISTURE IS UNDER-MODELED IN WEDGE SCENARIOS SO WILL INCREASE CLOUD COVER MORE THAN SUGGESTED BY PROFILES. MIXING WILL LIKELY ONLY REACH TO BELOW 900MB...AND LOW LEVEL 1000-900MB THICKNESSES SUPPORT TEMPS ONLY IN THE LOWER 60S NEAR WILMINGTON...TO AROUND 70 ACROSS THE PEE DEE REGION OF SC. HIGH DRIFTS OVERHEAD TUESDAY NIGHT ALLOWING FOR DECOUPLING IN THE LOWER ATMOSPHERE...AND CLEAR SKY CONDITIONS WILL ALLOW FOR DECENT RADIATIONAL COOLING. THE FLY-IN-THE-OINTMENT...AS IT IS...IS WHETHER SOME SLIGHT LOW LEVEL WAA BEGINS OVERNIGHT AS HIGH DRIFTS OFFSHORE...OR WHETHER WE CAN STAY PERFECTLY CALM. NEARLY ALL THE FORECAST PROFILES SUGGEST WARMING IN THE LOW LEVELS FROM 06Z-12Z WEDNESDAY AS LIGHT SOUTHERLY FLOW DEVELOPS AROUND DEPARTING HIGH PRESSURE. BELIEVE IT WILL BE TOUGH FOR SUCH SIGNIFICANT WARMING AFTER MANY HOURS OF NOCTURNAL INVERSION DEVELOPMENT...BUT WILL NOT DROP MINS AS LOW AS MAV NUMBERS...AND OPT FOR LOW 40S AREA WIDE...WITH THE COLDEST SPOTS POTENTIALLY TOUCHING 39. BY WEDNESDAY THE HIGH HAS DRIFTED OFFSHORE AND WARM SOUTHERLY RETURN FLOW COMES BACK INTO THE CAROLINAS. MOSTLY SUNNY SKY CONDITIONS WILL HELP RAISE TEMPS BACK TO ABOVE CLIMO...MID 70S AWAY FROM THE COAST...AND CONTINUED SOUTHERLY FLOW AT NIGHT WILL KEEPS TEMPS FROM FALLING MUCH OUT OF THE MID 50S AT NIGHT. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY...MOST INTERESTING PART OF THE LONG TERM OCCURS LATE THURSDAY WITH A COLD FRONTAL PASSAGE...BEFORE COOL HIGH PRESSURE SETTLES IN TO THE WEEKEND. MODERATELY POTENT S/W TROUGH DIGS FROM THE GREAT LAKES THROUGH NEW ENGLAND THURSDAY...SUPPRESSING THE UPPER RIDGE AND DRIVING A COLD FRONT THROUGH THE CAROLINAS. STILL NOTING TIMING DIFFERENCES IN THE GUIDANCE...BUT FOR PERSISTENCE WILL CONTINUE TO FAVOR THE SLIGHTLY SLOWER ECMWF/CMC OVER THE GFS. NOT MUCH IN THE WAY OF MOISTURE RETURN AHEAD OF THIS...ALTHOUGH MID LEVEL THETA-E RIDGE DOES TRY TO ADVECT INTO OUR AREA JUST AHEAD OF FROPA...SO WILL CARRY SCHC POP FOR SHOWERS THURSDAY EVE/NIGHT. IF THE SLOWER SOLUTION COMES TRUE...850MB TEMPS RISE TO 11C WHICH SUPPORTS TEMPS AT OR ABOVE 80 MOST AREAS AWAY FROM THE BEACHES...AND THURSDAY WILL BE THE WARMEST DAY OF THE EXTENDED. IF...HOWEVER...A FASTER FROPA OCCURS...THIS WILL OBVIOUSLY CUT TEMPS BACK ESPECIALLY ACROSS THE NORTH...AND WOULD INCREASE THE LIKELIHOOD OF AFTN SHOWERS ALONG THE BOUNDARY. FOR NOW WILL STICK WITH THE SLOWER SOLUTION. COOL HIGH PRESSURE BUILDS ACROSS THE REGION FRI/SAT RETURNING THE AREA TO NEAR CLIMO TEMPS...POSSIBLY BELOW CLIMO WITH SOME NE FLOW ON FRIDAY. GFS/ECMWF THEN DIVERGE CONSIDERABLY ON EVOLUTION AND STRENGTH OF ANOTHER NORTHERN STREAM S/W DROPPING ACROSS THE MIDWEST RIDGE. GFS IS FASTER AND WEAKER...CONTINUING ITS TREND THIS YEAR...SO WILL BLEND ECMWF/GFS BUT WITH ADDITIONAL WEIGHT ON THE FORMER. THIS WILL BRING INCREASED CHANCES FOR RAIN THROUGH THE WKND AS LOW PRESSURE DEVELOPS NEAR THE OHIO VALLEY. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... AS OF 06Z...ALTHOUGH SHOWERS HAVE ENDED ACROSS SOUTH CAROLINA... RADAR AND THE LATEST HRRR MODEL SUGGEST IT`S NOT OVER FOR NORTH CAROLINA JUST YET. SHOWERS ROTATING SOUTHWARD ON THE BACK SIDE OF THE DEPARTING UPPER LEVEL LOW PRESSURE AREA WILL AFFECT THE ILM TERMINAL THROUGH 09Z...WITH EVEN A FEW LIGHT SHOWERS POSSIBLE IN THE LBT VICINITY THROUGH 0730Z OR SO. THERE IS SOME UNCERTAINTY WITH REGARDS TO CEILING HEIGHTS...MVFR SHOULD PREDOMINATE...BUT IFR IS NOT OUT OF THE QUESTION PARTICULARLY AFTER 08Z. AFTER DAYBREAK WINDS WILL PICK UP...GUSTING OVER 20 KTS BY MID MORNING. SKIES WILL BECOME NEARLY CLEAR AS THE UPPER LOW EXITS OFFSHORE. EXTENDED OUTLOOK...VFR MONDAY NIGHT THROUGH WEDNESDAY. POSSIBLE MORNING FOG THURSDAY AND FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM MONDAY...LOW PRESSURE HAS MOVED EAST OF THE NC OUTER BANKS AND WILL MOVE FARTHER OUT TO SEA TODAY. ATTENTION WILL TURN TO HIGH PRESSURE IN CANADA JUST NORTH OF THE GREAT LAKES THAT WILL BUILD SOUTH TOWARD THE CAROLINAS. AS THIS HIGH MOVES SOUTH IT WILL PUSH A DRY COLD FRONT THROUGH THE AREA LATE THIS AFTERNOON. NORTH- NORTHEAST WINDS WILL INCREASE BEHIND THIS FRONT...REACHING 15-20 KT BY LATE THIS EVENING AND CONTINUING OVERNIGHT. THERE IS SOME POTENTIAL SEAS COULD REACH 6 FEET IN THE WATERS NEAR FRYING PAN SHOALS DUE TO THEIR EXPOSED POSITION IN THIS WIND DIRECTION...BUT CONFIDENCE IS TOO LOW TO RAISE AN ADVISORY AT THIS TIME. ELSEWHERE SEAS 2-4 FEET TODAY SHOULD BUILD TO 3-5 FT TONIGHT AWAY FROM SHORE WITH THE INCREASED WIND SPEEDS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...NE SURGE ONGOING AT THE START OF THE PERIOD AROUND WEDGE OF HIGH PRESSURE. AT LEAST CAUTIONARY HEADLINES APPEAR LIKELY TO BE IN EFFECT TUESDAY MORNING WITH 15-20 KT WINDS CREATING 4-5 FT NE WIND WAVES CONTROLLING THE WAVE SPECTRUM. DURING TUESDAY...HIGH PRESSURE DRIFTS OVER THE WATERS SO WINDS/WAVES RAPIDLY DECREASE THROUGH THE DAY...WINDS BECOMING NEARLY CALM OVERNIGHT WHILE SEAS FALL TO 1-2 FT. GRADIENT INCREASES WEDNESDAY AS HIGH PRESSURE DRIFTS OFFSHORE AND A COLD FRONT APPROACHES FROM THE NW. THIS PUTS THE WATERS INTO A PRE FRONTAL REGIME...WITH SW WINDS INCREASING TO 15-20 KTS FORCING SEAS BACK UP TO 3-5 FT...AND CAUTIONARY HEADLINES MAY ONCE AGAIN BE NECESSARY. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 AM MONDAY...CAUTIONARY HEADLINES POSSIBLY ONGOING AT THE START OF THE PERIOD AS A COLD FRONT APPROACHES FROM THE NORTHWEST. SW WINDS OF 15-20 KTS WILL VEER AND WEAKEN THROUGH THE DAY...BECOMING NORTH AROUND 10 KTS THURSDAY NIGHT. SW WIND WAVES OF 3-5 FT EARLY THURSDAY FALL TO 2-3 FT BY FRIDAY MORNING. A PERIOD OF CONFUSED SEAS IS LIKELY THURSDAY EVE AS THE WAVE SPECTRUM FEATURES TWO DOMINANT WIND WAVES...ONE SLOWLY WEAKENING FROM THE SW...WHILE A BUILDING NE WIND WAVE DEVELOPS. N/NE WINDS LESS THAN 10 KTS FRIDAY KEEP SEAS ONLY AROUND 2 FT THROUGH THE DAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...TRA SHORT TERM...JDW LONG TERM...JDW AVIATION...TRA/DL MARINE...TRA/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
101 AM EDT MON MAR 26 2012 .SYNOPSIS... DRIER AND COOLER CONDITIONS WILL SETTLE IN TODAY AND TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES. A BRIEF WARMING TREND WILL ENSUE DURING THE MIDDLE OF THIS WEEK...FOLLOWED BY A COLD FRONT ON THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 130 AM MONDAY...THE HRRR MODEL APPEARS TO HAVE AN EXCELLENT HANDLE ON CURRENT PRECIPITATION COVERAGE AND MOVEMENT AND IS THE BASIS FOR OUR EARLY MORNING UPDATE. WE HAVE INCREASED RAIN CHANCES TO NEAR 100 PERCENT ACROSS PENDER COUNTY AND THE LOWER CAPE FEAR RIVER BASIN FOR THE NEXT FEW HOURS. RADAR COMPOSITES SHOW A LARGE AREA OF RAIN EXTENDING AS FAR INLAND AS KINSTON AND GOLDSBORO THAT WILL ROTATE SOUTH AROUND THE DEPARTING UPPER LEVEL AND SURFACE LOW PRESSURE. ISENTROPIC DOWNGLIDE SHOULD HELP THE SOUTHERN EDGE DETERIORATE AFTER 2-3 AM...WITH MOST OF THE RAIN OVER WITH BY 4-5 AM. NO OTHER CHANGES AT THIS TIME. PREVIOUS DISCUSSION FROM 11 PM SUNDAY FOLLOWS... PER LATEST ANALYSIS...5H CUTOFF LOW AND ASSOCIATED COLD POOL IS OFF THE SE NC COAST AND SHOULD BEGIN TO GAIN SOME FORWARD SPEED OVERNIGHT AS THE WESTERLIES BEGIN TO INTERACT AND SLOWLY ABSORB THIS UPPER LOW INTO THE MAIN WESTERLY BELT. MODELS INDICATE THE CUTOFF/CLOSED LOW OPENS UP INTO AN OPEN WAVE MONDAY AND THEN GETS CAUGHT UP IN THE MAIN WESTERLIES DURING THE OVERNIGHT. BY 12Z...MODELS INDICATE THE UPPER LOW NOW NEARLY AN OPEN WAVE...AND SHOULD BE WELL OFFSHORE FROM CAPE HATTERAS. OVERALL...LOOK FOR IMPROVING WX AND SLOWLY IMPROVING SKY CONDITIONS FROM SW TO NE...ESPECIALLY AFTER THE MIDNIGHT HOUR. WILL INDICATE PARTIAL CLEARING FOR BASIC SKY CONDITIONS DURING THE PRE-DAWN HRS. VARIOUS MODEL MOS GUIDANCE INDICATE CONTINUED DECENT CHANCE FOR PCPN WELL AFTER MIDNIGHT. HOWEVER...WITH THE LOSS OF DAYTIME HEATING... WEAKENING LAPSE RATES DUE TO THE COLD POOL PULLING AWAY...AND SUBSIDENCE ALOFT BECOMING MORE DOMINANT AS TIME GOES BY...HAVE STAYED CLOSER TO A DRIER FORECAST AFTER THE MIDNIGHT HOUR. HAVE TWEAKED MIN TEMPS LOWER GIVEN CAA AND MOST TEMPS ACROSS THE ILM CWA HAVING REACHED WITHIN A CAT OF FORECAST MINS ALREADY. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 1:20 PM SUNDAY...MID LEVEL AMPLITUDE WILL RELAX THROUGH THE PERIOD ESPECIALLY WHEN COMPARED TO THE PATTERN WE HAVE SEEN THE PAST FEW DAYS. FOCUS SHIFTS FROM THUNDERSTORMS AND INSTABILITY TO WHAT IS BECOMING AN INTERESTING TEMPERATURE FORECAST FOR WEDNESDAY MORNING. EARLY ON...A BROAD NORTHERLY FLOW WILL DEVELOP IN THE WAKE OF A SURFACE TROUGH MOVING ACROSS WITH THE MID LEVEL LOW. A SECONDARY SURGE OF COOLER AIR ARRIVES AROUND 0600 UTC TUESDAY. THE SURFACE HIGH MOVES FROM THE NORTHEAST TO ESSENTIALLY OVERHEAD EARLY WEDNESDAY. NO POPS OR EVEN LITTLE CLOUD COVER IS EXPECTED THROUGH THE PERIOD. THE NAM/MET GUIDANCE IS CONSIDERABLY COOLER WITH 38 DEGREES IN LUMBERTON AND 44 WITH THE MAV FOR WEDNESDAY MORNING. IT APPEARS THE GFS HAS SOME HIGH LEVEL MOISTURE MOVING ACROSS FROM THE NORTHWEST THAT MAY KEEP IDEAL RADIATIONAL CONDITIONS FROM DEVELOPING. HAVE TRIMMED BACK LOWS A BIT BUT OVERALL FORECAST CONTINUES TO LEAN HEAVILY TOWARD THE MAV/GFS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 1:20 PM SUNDAY...LOW AMPLITUDE MID LEVEL FLOW ON WEDNESDAY WITH THE CAROLINAS ON THE SOUTHERN FRINGE OF A BELT OF WESTERLIES WHILE HIGH PRESSURE SITS OFF THE COAST. TEMPS BOUNCE BACK TO NORMAL AND CLOUD COVER SHOULD BE MINIMAL. MID LEVEL FLOW VEERS ON THURSDAY IN RESPONSE TO CONGEALING LOWS OFF CANADIAN MARITIMES AND A LARGELY MOISTURE-STARVED FRONT MANAGES TO PUSH THROUGH LATE IN THE DAY BUT NOT BEFORE A WARM AFTERNOON WITH HIGHS NEAR 80. FASTER TIMING OF THE FRONT IS POSSIBLE HOWEVER WHICH WOULD OBVIOUSLY LIMIT THE WARMTH AND COULD FAVOR A FEW TSTMS IF FROPA BETTER COINCIDES WITH PEAK HEATING. GUIDANCE AT ODDS WITH THE EXTENT OF BUILDING PRESSURES AND COLD AIR ADVECTION INTO THE CAROLINAS WITH RAMIFICATIONS RANGING FROM A RETURN TO CLIMO TEMPS TO DEVIATIONS BELOW CLIMO. EITHER WAY THIS HIGH APPEARS FATED TO WEAKEN AND MOVE OFF THE COAST FOR THE WEEKEND FAVORING A RETURN OF AT LEAST CLIMO TEMPERATURES. ISOLATED CONVECTION BORNE OF MESOSCALE PROCESSES CERTAINLY HARD TO RULE OUT BUT NO WIDESPREAD SYNOPTIC FORCING IS EXPECTED. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 06Z...ALTHOUGH SHOWERS HAVE ENDED ACROSS SOUTH CAROLINA... RADAR AND THE LATEST HRRR MODEL SUGGEST IT`S NOT OVER FOR NORTH CAROLINA JUST YET. SHOWERS ROTATING SOUTHWARD ON THE BACK SIDE OF THE DEPARTING UPPER LEVEL LOW PRESSURE AREA WILL AFFECT THE ILM TERMINAL THROUGH 09Z...WITH EVEN A FEW LIGHT SHOWERS POSSIBLE IN THE LBT VICINITY THROUGH 0730Z OR SO. THERE IS SOME UNCERTAINTY WITH REGARDS TO CEILING HEIGHTS...MVFR SHOULD PREDOMINATE...BUT IFR IS NOT OUT OF THE QUESTION PARTICULARLY AFTER 08Z. AFTER DAYBREAK WINDS WILL PICK UP...GUSTING OVER 20 KTS BY MID MORNING. SKIES WILL BECOME NEARLY CLEAR AS THE UPPER LOW EXITS OFFSHORE. EXTENDED OUTLOOK...VFR MONDAY NIGHT THROUGH WEDNESDAY. POSSIBLE MORNING FOG THURSDAY AND FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 130 AM MONDAY...SURFACE LOW PRESSURE IS EAST OF THE OUTER BANKS AND MOVING FARTHER OUT TO SEA. ONLY CHANGE TO THE FORECAST EARLY THIS MORNING WAS TO INCREASE RAIN CHANCES NORTH OF CAPE FEAR TO NEARLY 100 PERCENT AS RADAR INDICATES A LARGE BATCH OF RAIN ABOUT TO PUSH OFFSHORE. PRECIPITATION SHOULD REMAIN FAIRLY LIGHT...AND WILL BEGIN TO WRAP UP AFTER 4 AM. PREVIOUS DISCUSSION FROM 11 PM SUNDAY FOLLOWS... RAISED A SMALL CRAFT EXERCISE CAUTION FOR THE ILM NC WATERS ONLY. THE UPPER LOW AND ASSOCIATED SFC LOW TO SLIDE OFF CAPE HATTERAS LATE THIS EVENING...AND FURTHER OFFSHORE DURING THE PRE-DAWN MONDAY HRS. THE SFC PRESSURE PATTERN INDICATE WINDS WILL VEER FROM W TO NW DURING THE OVERNIGHT PERIOD. WIND SPEEDS WILL BE AROUND 15 KT...EXCEPT 15-20 KT ACROSS THE ILM NC WATERS. SEAS WILL RUN 2 TO 4 FT THRUOUT...WITH THE EXCEPTION OF 5 FOOTERS MAINLY RESERVED FOR THE OUTER WATERS FROM CAPE FEAR NORTHWARD. A 2 TO 4 FT 7 TO 8 SECOND PERIOD SOUTHERLY BORDERLINE SWELL WILL DOMINATE THE SIGNIFICANT SEAS. A 1 TO 3 FOOT WIND CHOP...WILL BLEND INTO THE SIG SEAS. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 1:20 PM SUNDAY...SOME STRONG WINDS AT THE BEGINNING OF THE PERIOD AS A SURFACE TROUGH WILL BE MOVING OFFSHORE. EXPECT A NORTHERLY FLOW AT 20-25 KNOTS. GRADIENT DECREASES SLOWLY DURING THE DAY ONLY TO INCREASE ONCE AGAIN AROUND 0600 UTC TUESDAY AS A SECONDARY FRONT/SURGE MOVES ACROSS. WINDS TURN MORE NORTHEAST AND INCREASE ONCE AGAIN TO A RANGE OF 20-25 KNOTS. GRADIENT DIMINISHES DRAMATICALLY LATE TUESDAY/EARLY WEDNESDAY AS THE CENTER OF HIGH PRESSURE;RE MOVES FROM PENNSYLVANIA TO BASICALLY OVERHEAD. WINDS STAY JUST BELOW SMALL CRAFT CRITERIA EARLY MONDAY AND AGAIN EARLY TUESDAY. SEAS MAY ECLIPSE SIX FEET BRIEFLY TUESDAY BUT WILL NOT ISSUE A HEADLINE AT THIS TIME DUE TO THE MARGINAL NATURE AND TIME CONSIDERATIONS. SEAS FOLLOW THE WINDS TUESDAY DECREASING DRAMATICALLY. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 1:20 PM SUNDAY...BERMUDA HIGH PRESSURE TO BRING A SOUTHWESTERLY WIND WEDNESDAY THAT MAY VEER WITH THE APPROACH/DEVELOPMENT OF SOME WEAK PIEDMONT TROUGHINESS. THIS MAY ALSO LEAD TO JUST ENOUGH OF AN UPTICK OF CONDITIONS THAT CAUTIONARY HEADLINES ARE NEEDED. THESE FACTORS REMAIN IN PLACE ON THURSDAY WHILE A COLD FRONT WHOSE TIMING IS A LITTLE UNCERTAIN APPROACHES FROM THE NNW. THE APPROACH OF THIS BOUNDARY MAY CAUSE ADDITIONAL VEERING THROUGH THURSDAY DEPENDING ON ITS SPEED AND TIME OF ARRIVAL. ASSUMING A THURSDAY EVENING FROPA A TURN TO A MORE NORTHERLY DIRECTION IS EXPECTED ON FRIDAY AND THE SURGE BEHIND THE FRONT ALSO WILL BE QUESTIONABLE...IN STRENGTH. THIS WILL END UP DICTATING WHETHER FRIDAY SEES A SLIGHT DETERIORATION IN WIND AND SEAS OR AN ACTUAL IMPROVEMENT OVER THURSDAY SHOULD THE WEAKER SOLUTIONS PAN OUT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...SHK/TRA NEAR TERM...DCH/TRA SHORT TERM...SHK LONG TERM...MBB AVIATION...HDL/TRA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
619 PM CDT TUE MAR 27 2012 .DISCUSSION... WINDS ARE DYING DOWN ACROSS THE SOUTHERN TIER WITH ONLY A COUPLE OF SITES FLIRTING WITH ADVISORY CRITERIA. WILL ALLOW WIND ADVISORY TO EXPIRE AT 7 PM CDT...AS SCHEDULED...BUT WINDS WILL CONTINUE TO BE QUITE GUSTY IN THE SOUTHERN VALLEY FOR THE NEXT SEVERAL HOURS. DO NOT EXPECT ANY CHANGES TO CURRENT FCST...AS NORMAL EVENING UPDATE WILL BE ISSUED LATER ON...HOWEVER CURRENT WV IS STARTING TO DEPICT A WK VORT OVER SRN SASK THAT BOTH NAM AND RUC HAVE PRODUCING SOME RAIN IN NE ND AFT MIDNIGHT. WILL SEE HOW 00Z NAM COMES IN...BUT MAY HOLD ON TO SOME SHOWER ACTIVITY ACROSS NORTHERN VALLEY A LITTLE FURTHER PAST MIDNIGHT THAN CURRENT FCST INDICATES. && .AVIATION... ALL SITES CURRENTLY MVFR OVC DECK JUST STARTING TO SHOW SOME EROSION ACROSS THE SOUTHERN RED RIVER VALLEY. PESSIMISTIC FAR WILL SCATTER OUT BY MIDNIGHT SO WILL SLOW THE TRANSITION FROM MVFR TO VFR FOR FAR UNTIL EARLY MORNING. WILL KEEP CONDS MVFR THROUGH AT LEAST NOON FOR ALL SITES EXCEPT FOR FAR...AS NOT IN FAVOR OF SCATTERING OUT AT NIGHT GIVEN EXTENT OF CLOUD COVER. WINDS WILL BEGIN TO TAPER OFF BY 03Z. && .PREV DISCUSSION... /ISSUED 304 PM CDT TUE MAR 27 2012/ SHORT TERM... SFC LOW PRESSURE AT 19Z WAS LOCATED NEAR KENORA ONTARIO. COLD ADVECTION AND STRATOCU HAVE OVERSPREAD OF THE FCST AREA. WINDEST CONDITONS REMAIN IN SE ND INTO WCTNRL MN WHERE SFC WINDS HAVE REMAINED SUSTAINED IN THE 25 TO 35 MPH RANGE AND WILL CONTINUE WIND ADVISORY IN THOSE AREAS OF SE ND/WCNTRL MN TIL 00Z. WINDS LIGHTER OVER NE ND/NW MN WITH MOSTLY 15 TO 25 MPH. RADAR SHOWS THE MAIN DEFORMATION ZONE HAS LIFTED NORTHEAST INTO MANITOBA WITH WRAPAROUND SCATTERED LIGHT RAIN/SPRINKLES OVERSPREAD NE ND/NW MN. SOME WET SNOW/RAIN MIX STILL LIKELY IN LANGDON-ROLLA AREAS THOUGH BULK OF PRECIP HAS MOVED NORTH. FOR TONIGHT EXPECT CLOUDS TO HOLD IN MOST AREAS...WITH SOME CLEARING LATE IN THE FAR SOUTHWESTERN FCST AREA. WINDS WILL DIMINISH BUT STILL HOLD UP AND ALONG WITH CLOUDS TEMPS WILL NOT FALL TOO FAR WITH LOW TO MID 30S OVERNIGHT. WILL REDUCE POPS SOME BUT MAINTAIN IDEA OF SOME SCATTERED SHOWERS OR RAIN/SNOW MIX OVER NE ND/NW MN. SKIES WILL CLEAR OUT WEDNESDAY AS HIGH DRIFTS SOUTHEAST OVER ERN ND IN THE AFTN. FAST ON ITS HEELS WILL BE NEXT SHORT WAVE WHICH WILL MOVE ACROSS THE AREA THURSDAY AFTN PRODUCING RAIN SHOWERS. 12Z ECMWF IS MORE POTENT WITH PRECIP THAN OTHER MODELS BUT ALL DO HAVE ENOUGH CONFIDENCE SO THAT RAISING POPS TO HIGH CHANCE OR LIKELY SEEMS WARRANTED ESP IN THE RED RIVER VALLEY INTO NW MN DURING THE DAY ON THURSDAY AS STRONG 850 MB THETA-E ADVECTION MOVES THROUGH. LOOK FOR ANOTHER QUICK BREAK LATER THURSDAY NIGHT INTO EARLY FRIDAY BEFORE NEXT SHORT WAVE MOVES THROUGH SOUTHERN CANADA. THIS WILL SPREAD A LOW THREAT FOR SHOWERS TO NE ND AND FAR NW MN FRIDAY. LONG TERM (FRI NIGHT-TUE)... MODELS INITIALIZED WELL THIS RUN AND IN GENERAL AGREEMENT SO WENT WITH A BLENDED SOLN FOR THIS PACKAGE. PATTERN REMAINS UNSETTLED WITH A BROAD UPPER RIDGE OVER THE NRN PLAINS TO START THE EXTENDED PERIOD. SOUTHERLY FLOW AND INCREASING THICKNESSES PROPPING UP TEMPS AHEAD OF NEXT WAVE CROSSING THE ROCKIES. RIDGE OVER DAKS/MN BECOMING HIGHER AMPLITUDE AS VIGOROUS WAVE DIGS INTO TROF OVER THE INTERMOUNTAIN WEST. HOWEVER...UPPER TROF EXPECTED TO BECOME MORE NEGATIVELY TILTED SLOWING DOWN PROGRESSION OF WAVE...AND INCREASING CHANCES FOR MEASURABLE PCPN OVER THE FA BY THE END OF THE PERIOD. AIRMASS FILTERING IN BEHIND THE SYSTEM SUFFICIENTLY COOL ENOUGH WHERE -RA/-SN MIX IS POSSIBLE IN THE FAR WEST. AVIATION... MAIN CHALLENGES FOR THIS TAF PERIOD ARE CIGS AND WINDS. 18Z SFC ANAL SHOWS LOW PRESSURE CENTERED OVER NW MN AND CONTINUING TO LIFT NE. BEST PRESSURE GRADIENT IN THE FAR SOUTH WITH BLAYER WINDS 30 TO 35 KTS COMBINED WITH A SHALLOW ADIABATIC LAYER ALLOWING WINDS TO MIX DOWN TO THE SFC. GRADIENT WEAKENS AS THE SYSTEM LIFTS NE...AND COOL CANADIAN HIGH PRESSURE SETTLES OVER THE REGION ALLOWING WINDS TO DECREASE. THUS...WINDS IN THE TAFS REFLECT CONTINUED MOVEMENT OF THE LOW. HOWEVER...WINDS UNRELIABLE AT TVF SO WINDS IN FORECAST REFLECT GENERAL TREND OVER THE AREA. OTHERWISE...PLENTY OF LOW LEVEL MOISTURE WRAPPING AROUND THE LOW AND UPSTREAM CIGS MVFR TO IFR SO REFLECTED TRENDS IN THE FORECAST. FREEZING LINE APPROACHING THE DVL BASIN AND INCLUDED -RASN FOR A FEW HOURS NEAR THE START OF THE TAF PERIOD AS A BAND OF SHOWERS MOVE THROUGH. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ024-028>030-038- 039-049-052-053. MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ002-003-022>024- 027>032-040. && $$ SPEICHER
AREA FORECAST DISCUSSION
NWS NORMAN OK
937 PM CDT TUE MAR 27 2012 .DISCUSSION... ADJUSTMENTS WERE MADE TO SKY COVER FOR LATE TONIGHT. THE RUC AND GFS AND HRRR ARE SIMILAR IN DEVELOPING LOW CLOUDS IN WESTERN OKLAHOMA AND/OR ADVECTING THEM ACROSS SOUTHERN OKLAHOMA FROM THE SOUTH. OTHERWISE LITTLE CHANGES ARE NECESSARY FOR THE OVERNIGHT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 58 82 60 81 / 10 10 20 20 HOBART OK 59 82 59 80 / 20 20 20 20 WICHITA FALLS TX 60 84 60 83 / 10 20 20 30 GAGE OK 54 85 56 85 / 20 20 30 20 PONCA CITY OK 58 83 61 84 / 20 20 30 20 DURANT OK 59 81 60 77 / 10 10 10 20 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 09/22
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1025 PM EDT TUE MAR 27 2012 .SYNOPSIS... DRY SURFACE HIGH WILL LINGER OVER THE AREA TONIGHT THROUGH WEDNESDAY. A WEAK COLD FRONT WILL THEN SWEEP ACROSS THE REGION EARLY THURSDAY FOLLOWED BY ANOTHER RIDGE OF DRY HIGH PRESSURE MOVING BACK IN BEHIND THE FRONT ON FRIDAY. A SERIES OF UPPER SHORTWAVE SYSTEMS WILL AFFECT OUR WEATHER THIS WEEKEND. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1030 PM EDT...GRIDS ARE GENERALLY IN GOOD SHAPE. A FEW TWEAKS WERE MADE TO THE TEMP AND DEWPOINT GRIDS...BUT THE TRENDS LOOK GOO. AS OF 740 PM EDT...THE TREND OF A FASTER THAN PROGGED INCREASE IN DEWPOINTS IS CONTINUING THIS EVENING. THIS INCREASES CONFIDENCE A LITTLE IN THE IDEA OF SOME RETURN FLOW STRATUS DEVELOPING ACROSS THE I-85 CORRIDOR BY SUNRISE. THEREFORE CLOUD COVER HAS BEEN INCREASED OVER THE SW PART OF THE FA LATE TONIGHT. AS OF 430 PM EDT...GRIDS ARE IN GOOD SHAPE WITH ONLY SOME THIN CI WHICH IS RESULTING IN VERY LITTLE OPAQUE SKY COVER. MINOR TWEAKS WERE MADE TO TEMPS AND DEWPOINTS. A TREND TOWARD SLIGHTLY HIGH DEWPOINTS IS BECOMING ESTABLISHED OVER THE UPSTATE AND NE GA...AND THESE AREAS MAY NEED TO HAVE TD/S ADJUSTED UP AS THE EVENING PROGRESSES. PREVIOUS DISCUSSIONS... SKY COVER ACROSS THE CWA SHOULD REMAIN CLEAR THROUGH THE EVENING HOURS...ONLY A FEW CONTRAILS. LATEST SATELLITE LOOP INDICATED A GATHERING AREA OF LOW CLOUDS ALONG THE GA COAST. A FEW MESOSCALE MODELS INDICATE THAT THE MOISTURE WILL ADVECT NW OVERNIGHT...REACHING THE CAROLINA PIEDMONT AND UPPER SAVANNAH RIVER VALLEY LATE TONIGHT INTO WEDNESDAY MORNING. HOWEVER...RECENT RUNS OF THE RUC AND LAMP MODELS HAVE BEEN BACKING AWAY FROM THIS SOLUTION...KEEPING THE MOISTURE FURTHER SOUTH ACROSS GA. I WILL USE A COMPROMISE IN THE FORECAST...INDICATING PARTLY CLOUDY CONDITIONS BY SUNRISE. LOW TEMPERATURES ARE EXPECTED TO RANGE FROM THE LOW 50S ACROSS THE UPPER SAVANNAH RIVER VALLEY TO THE L40S ACROSS THE MTN VALLEYS AND ALONG AND NORTH OF I-40. WEDNESDAY...A SLOW MOVING COLD FRONT...ORIENTED SW TO NE...WILL SLOWLY SLIDE SOUTHEAST ACROSS KY AND WV DURING THE AFTERNOON. AS THE FRONT APPROACHES...HIGH PRESSURE WILL REMAIN CENTERED NEAR THE FL PANHANDLE...PLACING THE CWA WITHIN A 4-6 MB PRESSURE GRADIENT. SOUTHWEST WINDS SHOULD INCREASE THROUGH THE AFTERNOON INTO THE TEENS GUSTING INTO THE L20S. TEMPERATURES SHOULD STEADILY WARM THROUGH THE DAY...PEAKING IN THE MID TO U70S EAST OF THE MTNS AND WITHIN THE MTN VALLEYS. HOWEVER...DEWPOINTS WILL REMAIN AROUND 50 DEGREES AND RH VALUES SHOULD FALL BELOW 40 PERCENT. FORECAST SOUNDINGS INDICATE THAT H85 FLOW WILL BECOME NEARLY DUE WEST WITH SPEEDS AROUND 30 KTS...RESULTING IN WIDESPREAD DOWNSLOPE FLOW ACROSS THE FOOTHILLS AND PIEDMONT. CIN VALUES MAY CONTINUE TO RANGE ABOVE 40 J/KG EAST OF THE MTNS THROUGH THE AFTERNOON. HOWEVER...THE COMBINATION OF UPSLOPE FLOW...POSSIBLE OUTFLOW BOUNDARY...AND MODERATE INSTABILITY SHOULD SUPPORT SCT SHRA/TSRA ACROSS THE TN BORDER COUNTIES BY LATE AFTERNOON...LITTLE TO NO CHC EAST. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 255 PM TUESDAY...WEAK SHORT WAVE MOVES NORTH OF THE AREA WEDNESDAY NIGHT. THE WAVE PUSHES A WEAK COLD FRONT SOUTH ACROSS THE AREA BY EARLY THURSDAY. BEST QG FORCING REMAINS WELL TO OUR NORTH. HOWEVER...THERE IS SOME WEAK UPPER DIVERGENCE ACROSS THE REGION LATE WEDNESDAY NIGHT. DEEP MOISTURE REMAINS LIMITED WITH THE FRONT WITH LITTLE IN THE WAY OF LOW LEVEL INFLOW DUE TO W TO SW WINDS AHEAD OF THE FRONT. BEST LOW LEVEL CONVERGENCE WILL BE OVER THE MTNS AS WELL. CONTINUED THE TREND OF HIGH CHC POP FOR THE WRN MTNS TAPERING OFF TO LOW CHC BLUE RIDGE. ALLOWED A BRIEF PERIOD OF SLIGHT CHC ACROSS THE ENTIRE CWFA DURING THE EVENING GIVEN THE ELEVATED INSTABILITY AND SOME WEAK FORCING. THAT SAID...PRECIP CHC OVER THE PIEDMONT IS LOW. STILL CANNOT RULE OUT AN ISOLATED SVR STORM OVER THE MTNS AND NRN TIER GIVEN THE MODERATE INSTABILITY AND DECENT SHEAR. ANY CONVECTION WILL QUICKLY END LATE WED NITE OR EARLY THU MORN WITH CLEARING SKIES. HIGH PRESSURE BUILDS IN THU NITE THEN SLIDES EAST FRI AS A WEAK WARM FRONT SLIDES BY TO OUR NW. THIS AND THE DEVELOPING SWLY FLOW SHUD BE ENUF FOR AN INCREASE IN CLOUDS. HOWEVER...NO PRECIP EXPECTED FOR NOW. LOWS 10 TO 15 DEGREES ABOVE NORMAL WED NITE FALL TO 5 TO 10 ABOVE THU NITE. HIGHS THU 10 TO 15 DEGREES ABOVE NORMAL IN THE CLEARING SKIES AND DEVELOPING DOWNSLOPE FLOW REMAIN NEARLY STEADY OVER THE MTNS FRI AND FALL AROUND 5 DEGREES ELSEWHERE. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 230 PM TUESDAY...THE LATEST MODELS ARE IN FAIR AGREEMENT WITH A SERIES OF UPPER SHORTWAVE SYSTEMS MOVING ACROSS THE REGION THIS WEEKEND WITH ANOTHER FRONTAL SYSTEM APPROACHING THE AREA FROM THE NORTHWEST BY NEXT TUESDAY. LATE FRIDAY AND SATURDAY...A WEAK UPPER SHORTWAVE TROUGH OVER THE GREAT LAKES FRIDAY WILL MOVE SE ACROSS THE REGION SATURDAY FOLLOWED BY ANOTHER SOUTHERN STREAM UPPER SHORTWAVE MOVING THROUGH ON SUNDAY. THE COMBINATION OF DIURNAL INSTABILITY AND SOME DEGREE OF UPPER FORCING WILL SUPPORT FOR THE DEVELOPMENT OF THUNDERSTORMS ACROSS MUCH OF THE REGION. SO I KEPT POPS IN THE 30S SAT/SUN. MONDAY AND TUESDAY...AN UPPER LOW OVER THE DAKOTAS MONDAY WILL MOVE SOUTHEAST ACROSS IN/KY...PUSHING A COLD FRONT SE INTO OUR FORECAST AREA BY LATE MON/EARLY TUESDAY. HOWEVER DUE TO THE UNCERTAINTY...I MENTIONED POPS ONLY IN THE 20S FOR MON NIGHT /TUES. DAYTIME TEMPERATURES WILL REMAIN IN THE UPPER 70S AND SOME 80S THROUGH OUT THE EXTENDED FORECAST PERIOD. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... AT KCLT AND ELSEWHERE...THE LATEST SREF GUIDANCE...BUFKIT SOUNDINGS AND OUR WORKSTATION WRF-ARW MODEL ARE INDICATING THAT STRATUS WILL BE POSSIBLE DURING THE MORNING HOURS ON WEDNESDAY. EVEN THE 18 UTC MAV MOS IS FINALLY CARRYING A PERIOD OF MVFR CIGS FROM 12-15 UTC AT THE UPSTATE SITES. I/LL FOLLOW THIS TREND AND HAVE MVFR CIGS DURING THIS PERIOD. THE LOW CLOUDS SHOULD ALSO AFFECT KCLT...ALBEIT AN HOUR OR TWO LATER THAN THE UPSTATE. NO RESTRICTIONS AT KAVL OR KHKY. WINDS WILL BE OUT OF THE SOUTH TONIGHT...VEERING TO THE SOUTHWEST WITH GUSTS UP TO 20 TO 22 KTS AT MOST SITES IN THE AFTN. NOT LOOKING FOR ANYTHING MORE THAN ISOLATED CONVECTION EAST OF THE MTNS TMRW. COVERAGE WILL GREATER OVER THE MTNS..ESP NEAR THE TN LINE...BUT STILL NOT GREAT ENUF TO ADD ANYTHING TO THE KAVL TAF. OUTLOOK...ANOTHER COLD FRONT IS EXPECTED TO MOVE IN FROM THE NW EARLY THURSDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS OVER THE NC MOUNTAINS RESULTING IN POSSIBLE CIG RESTRICTIONS LATE WED AND INTO THURS. HIGH PRESSURE WILL BUILD BACK INTO THE AREA BEHIND THE COLD FRONT ON FRIDAY. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...MCAVOY SHORT TERM...RWH LONG TERM...JOH AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
735 PM EDT TUE MAR 27 2012 .SYNOPSIS... DRY SURFACE HIGH WILL LINGER OVER THE AREA TONIGHT THROUGH WEDNESDAY. A WEAK COLD FRONT WILL THEN SWEEP ACROSS THE REGION EARLY THURSDAY FOLLOWED BY ANOTHER RIDGE OF DRY HIGH PRESSURE MOVING BACK IN BEHIND THE FRONT ON FRIDAY. A SERIES OF UPPER SHORTWAVE SYSTEMS WILL AFFECT OUR WEATHER THIS WEEKEND. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 740 PM EDT...THE TREND OF A FASTER THAN PROGGED INCREASE IN DEWPOINTS IS CONTINUING THIS EVENING. THIS INCREASES CONFIDENCE A LITTLE IN THE IDEA OF SOME RETURN FLOW STRATUS DEVELOPING ACROSS THE I-85 CORRIDOR BY SUNRISE. THEREFORE CLOUD COVER HAS BEEN INCREASED OVER THE SW PART OF THE FA LATE TONIGHT. AS OF 430 PM EDT...GRIDS ARE IN GOOD SHAPE WITH ONLY SOME THIN CI WHICH IS RESULTING IN VERY LITTLE OPAQUE SKY COVER. MINOR TWEAKS WERE MADE TO TEMPS AND DEWPOINTS. A TREND TOWARD SLIGHTLY HIGH DEWPOINTS IS BECOMING ESTABLISHED OVER THE UPSTATE AND NE GA...AND THESE AREAS MAY NEED TO HAVE TD/S ADJUSTED UP AS THE EVENING PROGRESSES. PREVIOUS DISCUSSIONS... SKY COVER ACROSS THE CWA SHOULD REMAIN CLEAR THROUGH THE EVENING HOURS...ONLY A FEW CONTRAILS. LATEST SATELLITE LOOP INDICATED A GATHERING AREA OF LOW CLOUDS ALONG THE GA COAST. A FEW MESOSCALE MODELS INDICATE THAT THE MOISTURE WILL ADVECT NW OVERNIGHT...REACHING THE CAROLINA PIEDMONT AND UPPER SAVANNAH RIVER VALLEY LATE TONIGHT INTO WEDNESDAY MORNING. HOWEVER...RECENT RUNS OF THE RUC AND LAMP MODELS HAVE BEEN BACKING AWAY FROM THIS SOLUTION...KEEPING THE MOISTURE FURTHER SOUTH ACROSS GA. I WILL USE A COMPROMISE IN THE FORECAST...INDICATING PARTLY CLOUDY CONDITIONS BY SUNRISE. LOW TEMPERATURES ARE EXPECTED TO RANGE FROM THE LOW 50S ACROSS THE UPPER SAVANNAH RIVER VALLEY TO THE L40S ACROSS THE MTN VALLEYS AND ALONG AND NORTH OF I-40. WEDNESDAY...A SLOW MOVING COLD FRONT...ORIENTED SW TO NE...WILL SLOWLY SLIDE SOUTHEAST ACROSS KY AND WV DURING THE AFTERNOON. AS THE FRONT APPROACHES...HIGH PRESSURE WILL REMAIN CENTERED NEAR THE FL PANHANDLE...PLACING THE CWA WITHIN A 4-6 MB PRESSURE GRADIENT. SOUTHWEST WINDS SHOULD INCREASE THROUGH THE AFTERNOON INTO THE TEENS GUSTING INTO THE L20S. TEMPERATURES SHOULD STEADILY WARM THROUGH THE DAY...PEAKING IN THE MID TO U70S EAST OF THE MTNS AND WITHIN THE MTN VALLEYS. HOWEVER...DEWPOINTS WILL REMAIN AROUND 50 DEGREES AND RH VALUES SHOULD FALL BELOW 40 PERCENT. FORECAST SOUNDINGS INDICATE THAT H85 FLOW WILL BECOME NEARLY DUE WEST WITH SPEEDS AROUND 30 KTS...RESULTING IN WIDESPREAD DOWNSLOPE FLOW ACROSS THE FOOTHILLS AND PIEDMONT. CIN VALUES MAY CONTINUE TO RANGE ABOVE 40 J/KG EAST OF THE MTNS THROUGH THE AFTERNOON. HOWEVER...THE COMBINATION OF UPSLOPE FLOW...POSSIBLE OUTFLOW BOUNDARY...AND MODERATE INSTABILITY SHOULD SUPPORT SCT SHRA/TSRA ACROSS THE TN BORDER COUNTIES BY LATE AFTERNOON...LITTLE TO NO CHC EAST. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 255 PM TUESDAY...WEAK SHORT WAVE MOVES NORTH OF THE AREA WEDNESDAY NIGHT. THE WAVE PUSHES A WEAK COLD FRONT SOUTH ACROSS THE AREA BY EARLY THURSDAY. BEST QG FORCING REMAINS WELL TO OUR NORTH. HOWEVER...THERE IS SOME WEAK UPPER DIVERGENCE ACROSS THE REGION LATE WEDNESDAY NIGHT. DEEP MOISTURE REMAINS LIMITED WITH THE FRONT WITH LITTLE IN THE WAY OF LOW LEVEL INFLOW DUE TO W TO SW WINDS AHEAD OF THE FRONT. BEST LOW LEVEL CONVERGENCE WILL BE OVER THE MTNS AS WELL. CONTINUED THE TREND OF HIGH CHC POP FOR THE WRN MTNS TAPERING OFF TO LOW CHC BLUE RIDGE. ALLOWED A BRIEF PERIOD OF SLIGHT CHC ACROSS THE ENTIRE CWFA DURING THE EVENING GIVEN THE ELEVATED INSTABILITY AND SOME WEAK FORCING. THAT SAID...PRECIP CHC OVER THE PIEDMONT IS LOW. STILL CANNOT RULE OUT AN ISOLATED SVR STORM OVER THE MTNS AND NRN TIER GIVEN THE MODERATE INSTABILITY AND DECENT SHEAR. ANY CONVECTION WILL QUICKLY END LATE WED NITE OR EARLY THU MORN WITH CLEARING SKIES. HIGH PRESSURE BUILDS IN THU NITE THEN SLIDES EAST FRI AS A WEAK WARM FRONT SLIDES BY TO OUR NW. THIS AND THE DEVELOPING SWLY FLOW SHUD BE ENUF FOR AN INCREASE IN CLOUDS. HOWEVER...NO PRECIP EXPECTED FOR NOW. LOWS 10 TO 15 DEGREES ABOVE NORMAL WED NITE FALL TO 5 TO 10 ABOVE THU NITE. HIGHS THU 10 TO 15 DEGREES ABOVE NORMAL IN THE CLEARING SKIES AND DEVELOPING DOWNSLOPE FLOW REMAIN NEARLY STEADY OVER THE MTNS FRI AND FALL AROUND 5 DEGREES ELSEWHERE. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 230 PM TUESDAY...THE LATEST MODELS ARE IN FAIR AGREEMENT WITH A SERIES OF UPPER SHORTWAVE SYSTEMS MOVING ACROSS THE REGION THIS WEEKEND WITH ANOTHER FRONTAL SYSTEM APPROACHING THE AREA FROM THE NORTHWEST BY NEXT TUESDAY. LATE FRIDAY AND SATURDAY...A WEAK UPPER SHORTWAVE TROUGH OVER THE GREAT LAKES FRIDAY WILL MOVE SE ACROSS THE REGION SATURDAY FOLLOWED BY ANOTHER SOUTHERN STREAM UPPER SHORTWAVE MOVING THROUGH ON SUNDAY. THE COMBINATION OF DIURNAL INSTABILITY AND SOME DEGREE OF UPPER FORCING WILL SUPPORT FOR THE DEVELOPMENT OF THUNDERSTORMS ACROSS MUCH OF THE REGION. SO I KEPT POPS IN THE 30S SAT/SUN. MONDAY AND TUESDAY...AN UPPER LOW OVER THE DAKOTAS MONDAY WILL MOVE SOUTHEAST ACROSS IN/KY...PUSHING A COLD FRONT SE INTO OUR FORECAST AREA BY LATE MON/EARLY TUESDAY. HOWEVER DUE TO THE UNCERTAINTY...I MENTIONED POPS ONLY IN THE 20S FOR MON NIGHT /TUES. DAYTIME TEMPERATURES WILL REMAIN IN THE UPPER 70S AND SOME 80S THROUGH OUT THE EXTENDED FORECAST PERIOD. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... AT KCLT AND ELSEWHERE...THE LATEST SREF GUIDANCE...BUFKIT SOUNDINGS AND OUR WORKSTATION WRF-ARW MODEL ARE INDICATING THAT STRATUS WILL BE POSSIBLE DURING THE MORNING HOURS ON WEDNESDAY. EVEN THE 18 UTC MAV MOS IS FINALLY CARRYING A PERIOD OF MVFR CIGS FROM 12-15 UTC AT THE UPSTATE SITES. I/LL FOLLOW THIS TREND AND HAVE MVFR CIGS DURING THIS PERIOD. THE LOW CLOUDS SHOULD ALSO AFFECT KCLT...ALBEIT AN HOUR OR TWO LATER THAN THE UPSTATE. NO RESTRICTIONS AT KAVL OR KHKY. WINDS WILL BE OUT OF THE SOUTH TONIGHT...VEERING TO THE SOUTHWEST WITH GUSTS UP TO 20 TO 22 KTS AT MOST SITES IN THE AFTN. NOT LOOKING FOR ANYTHING MORE THAN ISOLATED CONVECTION EAST OF THE MTNS TMRW. COVERAGE WILL GREATER OVER THE MTNS..ESP NEAR THE TN LINE...BUT STILL NOT GREAT ENUF TO ADD ANYTHING TO THE KAVL TAF. OUTLOOK...ANOTHER COLD FRONT IS EXPECTED TO MOVE IN FROM THE NW EARLY THURSDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS OVER THE NC MOUNTAINS RESULTING IN POSSIBLE CIG RESTRICTIONS LATE WED AND INTO THURS. HIGH PRESSURE WILL BUILD BACK INTO THE AREA BEHIND THE COLD FRONT ON FRIDAY. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...MCAVOY SHORT TERM...RWH LONG TERM...JOH AVIATION...MCAVOY
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
300 PM MDT MON MAR 26 2012 .DISCUSSION...20Z SURFACE ANALYSIS HAD LOW OVER CENTRAL WY WITH WELL DEFINED WARM FRONT ALONG I-90 AND COLD FRONT DEVELOPING INTO NORTHEAST CO. 7MB/3HR PRESSURE FALLS AHEAD OF LOW AS SHORTWAVE IS RAPIDLY MOVING INTO SOUTHEAST WY. HIGHLY ELEVATED RETURNS NOW SHOWING UP AHEAD OF SHORTWAVE AND ON NOSE OF 100KT JET STREAK. CONCERN THIS FORECAST IS DISPOSITION OF THESE STRONG WAVE. 12Z/18Z GUIDANCE IN PRETTY GOOD AGREEMENT. IT BRINGS SHORTWAVE OUT NEGATIVELY-TILTED REACHING EASTERN ND BY 12Z TUESDAY. SURFACE LOW RAPIDLY DEEPENS OVER NORTHEAST WY LATE THIS AFTERNOON AND RACES INTO EASTERN ND BY 12Z TUESDAY. COLD FRONT BEHIND LOW RACES EAST- NORTHEAST THROUGH THIS EVENING...PLOWING THROUGH THE CWA BY 06Z. AHEAD OF COLD FRONT...LOW 50S TD/S POOLING GIVING AROUND 1KJ/KG MLCAPE...BUT MLCIN FROM 50-100J/KG JUST AHEAD OF COLD FRONT. THIS WILL BE A TOUGH CAP TO BREAK FOR SURFACE BASED STORMS...BUT LATEST HRRR/LOCAL WRF MODEL SUGGESTS AS BEST UPPER LEVEL FORCING OVERTAKES COLD FRONT JUST NORTHEAST OF SURFACE LOW...WE SHOULD SEE A CLUSTER OF STORMS DEVELOP. DAMAGING WINDS POSSIBLE WITH ANY STORM...AND LARGE HAIL WITH ANY SUPERCELL THAT DEVELOPS GIVEN 0-6KM BULK SHEAR REACHING 20-30M/S. STORMS WOULD MOVE AROUND 45KTS TO THE NORTHEAST. WILL WATCH MESOSCALE DEVELOPMENT FOR SIGNS OF SURFACE BASED CONVECTION. OTHER BIG STORY WILL BE WIND BEHIND COLD FRONT. PRESSURE RISES FORECAST OF 7-11MB BEHIND INITIAL COLD FRONT. COMBINED WITH 850MB WINDS INCREASING TO 55KTS AND STRONG COLD AIR ADVECTION...IT SHOULD BE ENOUGH TO PUSH STRONG WEST-SOUTHWEST WINDS TO THE SURFACE OVER NORTHEAST WY/THE BLACK HILLS/SOUTHWEST SD EARLY THIS EVENING AND THEN OVER NORTHWEST THROUGH SOUTH CENTRAL SD MID- EVENING. SUBSIDENCE BEHIND COLD FRONT VERY IMPRESSIVE AND STRONG DRYING AND LINKAGE THROUGH 700MB. LATEST RUC SHOWING SYSTEM A LITTLE BIT SLOWER THAN PREVIOUSLY THOUGHT...BUT HEADLINES IN PLACE WILL ACCOUNT FOR THAT SCENARIO. AS LOW MOVES INTO ND LATER THIS EVENING...SECONDARY PRESSURE RISE SURGE MOVES INTO NORTHEAST WY/NORTHWEST SD KEEPING WINDS GOING THERE. WINDS SPEEDS SOUTH OF I-90 SHOULD DECREASE SOME AFTER 06Z. TUESDAY...TIGHT GRADIENT WITH 50KT 850MB NORTHWEST WINDS WILL KEEP HIGH WINDS GOING OVER NORTHWEST PORTIONS OF THE CWA THROUGH TUESDAY AFTERNOON. WILL LIKELY NEED AT LEAST A WIND ADVISORY FURTHER SOUTH ON THE SD PLAINS. TEMPERATURES WILL BE NEAR GUIDANCE WITH A FEW LINGERING SHOWERS OVER THE FAR NORTH UNDER CYCLONIC FLOW ALOFT. TUESDAY NIGHT/WEDNESDAY...UPPER RIDGE BUILDS INTO THE CWA BRINGING QUIET WEATHER TO THE AREA. EXTENDED...A MAINLY DRY AND WARM WEATHER PATTERN CAN BE EXPECTED LATE THIS WEEK THROUGH THE WEEKEND AS A WEAK UPPER LEVEL RIDGE BUILDS OVER THE REGION. A WEAK UPPER LEVEL DISTURBANCE AND COOL FRONT PASSING THROUGH THE RIDGE COULD BRING A FEW SHOWERS AND STORMS TO SOUTH CENTRAL SD THURSDAY. HIGHS THROUGH THE END OF THE WEEK WILL BE IN THE 60S AND 70S...WITH THE WARMEST DAY LIKELY BEING SATURDAY. COOLER AIR WILL PUSH INTO THE AREA SUNDAY AS AN UPPER TROUGH CROSSES THE REGION. THIS WILL ALSO BRING CHANCES FOR PRECIPITATION EARLY NEXT WEEK. LIKELY TO BEGIN BUILDING INTO THE WESTERN PORTIONS OF THE AREA ON SUNDAY AS RIDGE SHIFTS TO THE EAST OF THE REGION. && .AVIATION...18Z TAF UPDATE A STRONG LOW PRESSURE SYSTEM WILL SWEEP ACROSS THE AREA LATE THIS AFTERNOON AND EVENING...BRINGING VERY STRONG WEST TO SOUTHWEST WINDS ACROSS THE AREA. SUSTAINED WINDS OF 30 TO 45 MPH AND GUSTS TO 60 MPH CAN BE EXPECTED. GUSTY WINDS WILL LINGER THROUGH TUESDAY MORNING ACROSS MUCH OF WESTERN SD. THERE IS A CHANCE FOR SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT AS THE SYSTEM MOVES THROUGH. SEVERE THUNDERSTORMS WILL BE POSSIBLE EARLY THIS EVENING...MAINLY ACROSS NORTHWEST AND WEST CENTRAL SOUTH DAKOTA PLAINS. && .FIRE WEATHER...A STRONG STORM SYSTEM WILL CROSS THE AREA TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO PARTS OF AREA THROUGH TONIGHT. A COLD FRONT WILL CROSS THE AREA LATE THIS AFTERNOON INTO THIS EVENING BRINGING VERY STRONG WESTERLY WINDS. THESE WINDS WILL GRADUALLY SHIFT TO THE NORTHWEST TONIGHT WHILE DECREASING. HOWEVER THE VERY STRONG WINDS ACROSS NORTHWEST INTO CENTRAL SOUTH DAKOTA WILL CONTINUE THROUGH THE DAY TUESDAY. TEMPERATURES TUESDAY ARE EXPECTED TO RISE INTO THE UPPER 50S TO UPPER 60S WHILE RELATIVE HUMIDITIES WILL DROP TO AS LOW AS 15 PERCENT. THESE CONDITIONS WILL PRODUCE CRITICAL FIRE WEATHER CONDITIONS ACROSS MUCH OF THE AREA THROUGH THIS EVENING...AND AGAIN TUESDAY. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...HIGH WIND WARNING UNTIL 6 AM MDT TUESDAY FOR CENTRAL BLACK HILLS- CUSTER CO PLAINS-HERMOSA FOOT HILLS-NORTHERN BLACK HILLS- RAPID CITY-SHANNON-SOUTHERN BLACK HILLS-SOUTHERN FOOT HILLS. RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR BADLANDS AREA- NORTHERN BLACK HILLS-NORTHWESTERN SOUTH DAKOTA PLAINS- SOUTHERN BLACK HILLS-SOUTHWESTERN SOUTH DAKOTA. RED FLAG WARNING FROM 10 AM TO 6 PM MDT TUESDAY FOR BADLANDS AREA-CENTRAL SOUTH DAKOTA PLAINS-NORTHERN BLACK HILLS- NORTHWESTERN SOUTH DAKOTA PLAINS-SOUTH CENTRAL SOUTH DAKOTA- SOUTHERN BLACK HILLS-SOUTHWESTERN SOUTH DAKOTA. HIGH WIND WARNING FROM 6 PM THIS EVENING TO 6 AM MDT TUESDAY FOR BENNETT-JACKSON. HIGH WIND WARNING FROM 9 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MELLETTE-TODD-TRIPP. HIGH WIND WARNING UNTIL MIDNIGHT MDT TONIGHT FOR FALL RIVER. HIGH WIND WARNING FROM 6 PM THIS EVENING TO 6 PM MDT TUESDAY FOR BUTTE-HAAKON-HARDING-NORTHERN MEADE CO PLAINS-PENNINGTON CO PLAINS-PERKINS-SOUTHERN MEADE CO PLAINS-ZIEBACH. HIGH WIND WARNING UNTIL 6 PM MDT TUESDAY FOR NORTHERN FOOT HILLS- STURGIS/PIEDMONT FOOT HILLS. WY...HIGH WIND WARNING UNTIL 6 AM MDT TUESDAY FOR WYOMING BLACK HILLS. RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR LOWER ELEVATIONS OF CROOK AND WESTON COUNTIES-NORTHERN CAMPBELL- SOUTHERN CAMPBELL-WYOMING BLACK HILLS. RED FLAG WARNING FROM 10 AM TO 6 PM MDT TUESDAY FOR LOWER ELEVATIONS OF CROOK AND WESTON COUNTIES-NORTHERN CAMPBELL- SOUTHERN CAMPBELL-WYOMING BLACK HILLS. HIGH WIND WARNING UNTIL MIDNIGHT MDT TONIGHT FOR WESTON. HIGH WIND WARNING FROM 6 PM THIS EVENING TO 6 PM MDT TUESDAY FOR NORTHEASTERN CROOK. HIGH WIND WARNING UNTIL 6 AM MDT TUESDAY FOR NORTHERN CAMPBELL- SOUTHERN CAMPBELL-WESTERN CROOK. && $$ SHORT TERM...HELGESON LONG TERM....CALDERON AVIATION...CALDERON
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1244 PM CDT MON MAR 26 2012 .AVIATION.../FOR THE 18Z TAF ISSUANCE/ VFR CONDITIONS THROUGH THE PERIOD BUT WINDS WILL CREATE SOME PROBLEMS. SOUTHEAST WINDS THROUGH TONIGHT WILL AVERAGE 20 TO 35 MPH WHILE WEST WINDS ON TUESDAY WILL RUN ABOUT 30 TO 40 MPH WITH A FEW GUSTS TO NEAR 50 MPH...ESPECIALLY NORTH OF INTERSTATE 90. ISOLATED THUNDERSTORMS WILL BE POSSIBLE LATER THIS EVENING BUT COVERAGE IS EXPECTED TO REMAIN LOW. OTHERWISE...VFR CEILINGS AND VISIBILITIES ARE EXPECTED. /08 && .DISCUSSION... MESSY FORECAST THE NEXT 24 TO 36 HOURS WITH WIND...FIRE WEATHER AND THUNDERSTORMS WITH AN ISOLATED SEVERE THREAT ALL CONCERNS. TO START...ADDED THE REMAINING FEW COUNTIES IN NW IA TO THE WIND ADVISORY WITH SLB ALREADY SUSTAINED AT 30 MPH. THE REMAINDER OF THE AREA LOOKS GOOD AND WILL BE VERY WINDY TODAY. TEMPERATURES WILL START TO SURGE DURING THE AFTERNOON AS WINDS TURN MORE SOUTHERLY. QUITE A BIT OF CLOUD COVER WILL BE HOWEVER SO NOT EXPECTING HIGH TEMPERATURES TO GET OUT OF HAND. WHAT WE HAVE SEEMS REASONABLE BUT MAY NEED TO CUT BACK A COUPLE OF DEGREES IN PLACES. THE NEXT CONCERN WILL BE THUNDERSTORMS. THE MORNING SOUNDINGS FROM LBF AND UNR ARE VERY DRY AND VERY WARM. WILL BE QUITE DIFFICULT TO GET THUNDERSTORMS GOING IN THIS ENVIRONMENT AND THE LATEST NAM GIVES US NOTHING THROUGH THE NIGHT. THE HRRR ALSO LOOKS DRY THROUGH THE EARLY EVENING. SO...WILL MAINTAIN SOME 20 TO 30 POPS AND WITH THE SHEAR STILL HAVE SOME CONCERN ABOUT A SEVERE THREAT BUT STARTING TO LOOK DIFFICULT. WILL NEED TO WATCH CENTRAL SD LATER TODAY FOR POSSIBLE DEVELOPMENT. WILL GO AHEAD EXTEND THE WIND ADVISORY INTO TUESDAY AS WELL AS ISSUE A RED FLAG WARNING FOR TUESDAY. THE RED FLAG WARNING WILL BE FOR THE SD ZONES AND NW IA ZONES WITH A FIRE WEATHER WATCH IN PLACE FOR SW MN WHERE THE RH VALUES WILL BE A LITTLE HIGHER. IN ALL LIKELIHOOD A RED FLAG WARNING WILL BE NEEDED FOR SW MN WITH SUSTAINED WINDS OF 30 TO 40 MPH. /08 && .PREV DISCUSSION.../ISSUED AT 410 AM CDT/ A POTENT STORM SYSTEM DEVELOPING IN THE NORTHERN HIGH PLAINS TODAY WILL BRING SOME UNSETTLED WEATHER TO THE REGION TODAY AND TONIGHT. DEEP TROUGH OVER THE FOUR CORNER REGION WILL STRENGTHEN AND BECOME CUT OFF AS IT EMERGES IN THE WESTERN PLAINS THIS AFTERNOON THEN TRACKS NORTHEASTWARD ACROSS THE CENTRAL AND NORTHERN PLAINS THROUGH TONIGHT. MEANWHILE...A SURFACE LOW IS EXPECTED TO FORM OVER THE WESTERN DAKOTAS THIS EVENING AND TONIGHT. STRONG THETA E ADVECTION OUT AHEAD OF THIS SYSTEM IS TRIGGERING SOME SCATTERED SHOWERS AND THUNDERSTORMS EARLY THIS MORNING ACROSS NORTHEAST SD AND SOUTHERN MN ALONG THE BOUNDARY. EXPECT THESE STORMS TO PERSIST IN THIS AREA THROUGH THIS MORNING WITH A MINOR WAVE TRACKING NORTHEAST THROUGH THE FORECAST AREA INTO THE EARLY AFTERNOON EXPANDING THE ISOLATED THUNDERSTORM POTENTIAL ACROSS THE BULK OF THE CWA. DESPITE THE STRENGTHENING LOW LEVEL JET/SHEAR AND MODEST MID LEVEL INSTABILITY...THE MAJOR LIMITING FACTOR TODAY WILL BE THE VERY STRONG CAP IN PLACE ACROSS THE REGION WHICH WILL BE DIFFICULT TO OVERCOME. ILL DEFINED SURFACE BOUNDARY SLIPS THROUGH THE FORECAST AREA TONIGHT. AHEAD OF THE FRONT...CAP WEAKENS A BIT THIS EVENING AS THE TROUGH STRENGTHENS. THIS COULD ALLOW SOME STORMS TO DEVELOP IN THE WEST IN THE EVENING AND TRACK EASTWARD THROUGH THE CWA OVERNIGHT. MUCAPE LOOKS LESS IMPRESSIVE DURING THIS PERIOD WHILE SHEAR REMAINS QUITE STRONG. COULD SEE SOME ELEVATED STORMS WITH POSSIBLE SEVERE HAIL AND WINDS INTO THE EARLY MORNING HOURS. ALSO OF CONCERN THIS AFTERNOON WILL BE SURFACE WINDS WITH A STRONG PRESSURE GRADIENT DEVELOPING AND AN STRONG LLJ IN PLACE. WHILE THE COPIOUS CLOUDS AND SOUTHEAST WINDS DO NOT PRESENT THE BEST MIXING POTENTIAL...DO THINK SOME BORDERLINE ADVISORY SUSTAINED WINDS WILL BE ATTAINABLE ACROSS OUR SD...MN...NE AND NORTHERN IA ZONES THIS AFTERNOON. HAVE ISSUED A WIND ADVISORY FOR THE BETTER PART OF THE CWA FOR THIS AFTERNOON AND EVENING. GRADIENT REMAINS QUITE TIGHT INTO TUESDAY AS THE DEEP SURFACE LOW MOVES INTO NORTHERN MINNESOTA AND COLD AIR ADVECTION RUSHES IN BEHIND THE TROUGH. LOOKS LIKE ANOTHER POTENTIAL WIND ADVISORY SITUATION IN PARTICULAR ACROSS THE NORTH. WITH TODAYS HEADLINE IN PLACE...WILL HOLD OFF ISSUING FOR TUESDAY AS WELL. NORTHWEST FLOW SETTLES IN TUESDAY AND WEDNESDAY WITH DRY WEATHER AND COOLER TEMPERATURES...ALBEIT STILL WELL ABOVE NORMALS. BY WEDNESDAY...HIGHS WILL ONLY BE IN THE MID 50S TO UPPER 60S. RIDGING BRINGS SOUTHERLY WINDS AND WARMER TEMPERATURES ON THURSDAY WITH SOME SCATTERED THUNDERSTORMS POSSIBLE IN THE AFTERNOON AND OVERNIGHT WITH THE ARRIVAL OF A SHORTWAVE. MODELS BEGIN TO DIVERGE SIGNIFICANTLY INTO THE WEEKEND WITH THE HANDLING OF RIDGE AND TROUGH FEATURES AND THEREFORE CONFIDENCE IS QUITE LOW. FOLLOWED THE BLENDED SOLUTION FOR THIS TIME FRAME. && .FSD WATCHES/WARNINGS/ADVISORIES... IA...RED FLAG WARNING FROM 11 AM TO 10 PM CDT TUESDAY FOR IAZ300. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR IAZ001>003-012>014- 020>022-031-032. FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR IAZ301. MN...WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR MNZ071-072-080-081-089- 090-097-098. FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR MNZ900. NE...RED FLAG WARNING FROM 11 AM TO 10 PM CDT TUESDAY FOR NEZ249. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR NEZ013-014. SD...RED FLAG WARNING FROM 11 AM TO 10 PM CDT TUESDAY FOR SDZ255>258. WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR SDZ038>040-050-052>071. && $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1110 AM CDT MON MAR 26 2012 .DISCUSSION... MESSY FORECAST THE NEXT 24 TO 36 HOURS WITH WIND...FIRE WEATHER AND THUNDERSTORMS WITH AN ISOLATED SEVERE THREAT ALL CONCERNS. TO START...ADDED THE REMAINING FEW COUNTIES IN NW IA TO THE WIND ADVISORY WITH SLB ALREADY SUSTAINED AT 30 MPH. THE REMAINDER OF THE AREA LOOKS GOOD AND WILL BE VERY WINDY TODAY. TEMPERATURES WILL START TO SURGE DURING THE AFTERNOON AS WINDS TURN MORE SOUTHERLY. QUITE A BIT OF CLOUD COVER WILL BE HOWEVER SO NOT EXPECTING HIGH TEMPERATURES TO GET OUT OF HAND. WHAT WE HAVE SEEMS REASONABLE BUT MAY NEED TO CUT BACK A COUPLE OF DEGREES IN PLACES. THE NEXT CONCERN WILL BE THUNDERSTORMS. THE MORNING SOUNDINGS FROM LBF AND UNR ARE VERY DRY AND VERY WARM. WILL BE QUITE DIFFICULT TO GET THUNDERSTORMS GOING IN THIS ENVIRONMENT AND THE LATEST NAM GIVES US NOTHING THROUGH THE NIGHT. THE HRRR ALSO LOOKS DRY THROUGH THE EARLY EVENING. SO...WILL MAINTAIN SOME 20 TO 30 POPS AND WITH THE SHEAR STILL HAVE SOME CONCERN ABOUT A SEVERE THREAT BUT STARTING TO LOOK DIFFICULT. WILL NEED TO WATCH CENTRAL SD LATER TODAY FOR POSSIBLE DEVELOPMENT. WILL GO AHEAD EXTEND THE WIND ADVISORY INTO TUESDAY AS WELL AS ISSUE A RED FLAG WARNING FOR TUESDAY. THE RED FLAG WARNING WILL BE FOR THE SD ZONES AND NW IA ZONES WITH A FIRE WEATHER WATCH IN PLACE FOR SW MN WHERE THE RH VALUES WILL BE A LITTLE HIGHER. IN ALL LIKELIHOOD A RED FLAG WARNING WILL BE NEEDED FOR SW MN WITH SUSTAINED WINDS OF 30 TO 40 MPH. /08 && .PREV DISCUSSION.../ISSUED AT 410 AM CDT/ A POTENT STORM SYSTEM DEVELOPING IN THE NORTHERN HIGH PLAINS TODAY WILL BRING SOME UNSETTLED WEATHER TO THE REGION TODAY AND TONIGHT. DEEP TROUGH OVER THE FOUR CORNER REGION WILL STRENGTHEN AND BECOME CUT OFF AS IT EMERGES IN THE WESTERN PLAINS THIS AFTERNOON THEN TRACKS NORTHEASTWARD ACROSS THE CENTRAL AND NORTHERN PLAINS THROUGH TONIGHT. MEANWHILE...A SURFACE LOW IS EXPECTED TO FORM OVER THE WESTERN DAKOTAS THIS EVENING AND TONIGHT. STRONG THETA E ADVECTION OUT AHEAD OF THIS SYSTEM IS TRIGGERING SOME SCATTERED SHOWERS AND THUNDERSTORMS EARLY THIS MORNING ACROSS NORTHEAST SD AND SOUTHERN MN ALONG THE BOUNDARY. EXPECT THESE STORMS TO PERSIST IN THIS AREA THROUGH THIS MORNING WITH A MINOR WAVE TRACKING NORTHEAST THROUGH THE FORECAST AREA INTO THE EARLY AFTERNOON EXPANDING THE ISOLATED THUNDERSTORM POTENTIAL ACROSS THE BULK OF THE CWA. DESPITE THE STRENGTHENING LOW LEVEL JET/SHEAR AND MODEST MID LEVEL INSTABILITY...THE MAJOR LIMITING FACTOR TODAY WILL BE THE VERY STRONG CAP IN PLACE ACROSS THE REGION WHICH WILL BE DIFFICULT TO OVERCOME. ILL DEFINED SURFACE BOUNDARY SLIPS THROUGH THE FORECAST AREA TONIGHT. AHEAD OF THE FRONT...CAP WEAKENS A BIT THIS EVENING AS THE TROUGH STRENGTHENS. THIS COULD ALLOW SOME STORMS TO DEVELOP IN THE WEST IN THE EVENING AND TRACK EASTWARD THROUGH THE CWA OVERNIGHT. MUCAPE LOOKS LESS IMPRESSIVE DURING THIS PERIOD WHILE SHEAR REMAINS QUITE STRONG. COULD SEE SOME ELEVATED STORMS WITH POSSIBLE SEVERE HAIL AND WINDS INTO THE EARLY MORNING HOURS. ALSO OF CONCERN THIS AFTERNOON WILL BE SURFACE WINDS WITH A STRONG PRESSURE GRADIENT DEVELOPING AND AN STRONG LLJ IN PLACE. WHILE THE COPIOUS CLOUDS AND SOUTHEAST WINDS DO NOT PRESENT THE BEST MIXING POTENTIAL...DO THINK SOME BORDERLINE ADVISORY SUSTAINED WINDS WILL BE ATTAINABLE ACROSS OUR SD...MN...NE AND NORTHERN IA ZONES THIS AFTERNOON. HAVE ISSUED A WIND ADVISORY FOR THE BETTER PART OF THE CWA FOR THIS AFTERNOON AND EVENING. GRADIENT REMAINS QUITE TIGHT INTO TUESDAY AS THE DEEP SURFACE LOW MOVES INTO NORTHERN MINNESOTA AND COLD AIR ADVECTION RUSHES IN BEHIND THE TROUGH. LOOKS LIKE ANOTHER POTENTIAL WIND ADVISORY SITUATION IN PARTICULAR ACROSS THE NORTH. WITH TODAYS HEADLINE IN PLACE...WILL HOLD OFF ISSUING FOR TUESDAY AS WELL. NORTHWEST FLOW SETTLES IN TUESDAY AND WEDNESDAY WITH DRY WEATHER AND COOLER TEMPERATURES...ALBEIT STILL WELL ABOVE NORMALS. BY WEDNESDAY...HIGHS WILL ONLY BE IN THE MID 50S TO UPPER 60S. RIDGING BRINGS SOUTHERLY WINDS AND WARMER TEMPERATURES ON THURSDAY WITH SOME SCATTERED THUNDERSTORMS POSSIBLE IN THE AFTERNOON AND OVERNIGHT WITH THE ARRIVAL OF A SHORTWAVE. MODELS BEGIN TO DIVERGE SIGNIFICANTLY INTO THE WEEKEND WITH THE HANDLING OF RIDGE AND TROUGH FEATURES AND THEREFORE CONFIDENCE IS QUITE LOW. FOLLOWED THE BLENDED SOLUTION FOR THIS TIME FRAME. && .AVIATION.../FOR THE 12Z TAF ISSUANCE/ GENERALLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. OUTSIDE CHANCE OF ELEVATED THUNDERSTORMS THIS MORNING FORMING IN NORTHEAST NEBRASKA AND LIFTING NORTH WITH TIME. DUE TO SCATTERED NATURE AND LOW CONFIDENCE...DID NOT INCLUDE ANY MENTION IN TAFS. STRONG GUSTY SOUTHERLY WINDS EXPECTED ACROSS THE FORECAST AREA TODAY. WINDS WILL SLOWLY DECREASE TONIGHT AS COLD FRONT MOVES THROUGH THE AREA. COLD FRONT WILL MOVE THROUGH WITH STRONG WEST TO NORTHWEST WINDS BEHIND THE FRONT. OUTSIDE CHANCE OF A THUNDERSTORM ALONG THE FRONT. ATMOSPHERIC SOUNDINGS LOOK HOPELESSLY CAPPED...SO ONLY INCLUDED CB MENTION AT KHON TERMINAL FOR NOW. && .FSD WATCHES/WARNINGS/ADVISORIES... IA...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR IAZ001>003-012>014-020. MN...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR MNZ071-072-080-081-089-090-097-098. NE...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR NEZ013-014. SD...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR SDZ038>040-050-052>071. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
916 PM CDT TUE MAR 27 2012 .UPDATE... MCS ENTERING THE FAR WESTERN VAL VERDE COUNTY...WITH THE LEADING EDGE OF STORMS HAVE SHOWN A SLIGHT WEAKENING TREND THE LAST HOUR. 00Z RUC AND NAM SHOW CONVECTION WEAKENING THRU 06Z...ALTHOUGH WILL KEEP LOW POPS IN ACROSS THE RIO GRANDE PLAINS OVER THE WESTERN 3RD OF THE CWA A FEW HOURS LONGER...SIMILAR TO LAST NIGHT. OTHERWISE ONGOING FORECAST IN GOOD SHAPE AND NO MAJOR CHANGES WILL BE NEEDED. && .PREV DISCUSSION... /ISSUED 635 PM CDT TUE MAR 27 2012/ AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE EVENING. THE COMPLEX OF THUNDERSTORMS ACROSS THE BIG BEND REGION IS MAKING SLOW S/SW-WRD PROGRESS THIS EVENING. LATEST RUC ANALYSIS SUGGESTS THAT THE TSRA WILL CONTINUE TO MOVE SW-WRD THIS EVENING...BUT SHEAR APART/DISSIPATE BEFORE REACHING KDRT. HAVE THEREFORE OPTED TO MENTION CB AROUND KDRT LATER TONIGHT...BUT CONFIDENCE IS TOO LOW TO WARRANT EXPLICIT MENTION OF TSRA AT THE TERMINAL. OTHERWISE...SHRA/TSRA EARLIER THIS AFTERNOON ACROSS THE RIO GRANDE PLAINS AND ADJACENT AREAS IS RAPIDLY TRENDING DOWNWARD AND SHOULD CONTINUE TO DO SO WITH THE LOSS OF DAYTIME HEATING. ANTICIPATE ANOTHER ROUND OF MVFR STRATUS AOB 2KFT TO SETTLE IN ALONG THE I-35 CORRIDOR BY ABOUT 06Z. CIGS WILL LOWER AND SPREAD WEST OVERNIGHT...WITH LIFR CIGS POSSIBLE AT KAUS/KSAT/KSSF IN THE NEAR-DAYBREAK HOURS. SIMILAR TO TODAY...CONDITIONS WILL BE SLOW TO IMPROVE...BUT VFR CONDITIONS WILL RETURN AROUND/AFTER 18Z. PREV DISCUSSION... /ISSUED 331 PM CDT TUE MAR 27 2012/ DISCUSSION... THE SOUTHERN PLAINS SITS UNDER THE BACKSIDE OF AN UPPER LEVEL RIDGE FROM 700-250MB THIS AFTERNOON. WE ARE BEGINNING TO SEE A SLOW SHIFT IN THE PATTERN. HEIGHTS HAVE FALLEN SLIGHTLY OVER THE PAST DAY. THIS COMBINED WITH STRONG HEATING OVER THE MOUNTAINS IN NORTHERN MEXICO IS ALLOWING THUNDERSTORMS TO FORM. SIMILAR TO LAST NIGHT EXPECT STORMS THROUGH THE EVENING...BUT QUESTION IS WHETHER THEY CAN MAKE ACROSS THE PLAINS INTO TX. ATMOSPHERE IS FAIRLY CAPPED OVER OUR CWA...SO HAVE ONLY SLIGHT CHANCE POPS OVER THE WESTERN THIRD OF THE AREA. ANY STORMS THAT DO MAKE IT ACROSS MAY BE STRONG WITH SMALL HAIL AND GUSTY WINDS. WED LOOKS VERY SIMILAR TO TODAY WITH PERHAPS A LITTLE BETTER CHANCE OF STORMS MAKING ACROSS NORTHERN MEXICO INTO TX. THU THE UPPER TROUGH WHICH IS OVER THE WEST COAST WILL APPROACH TX AND THIS WILL BRING A BETTER CHANCE FOR THUNDERSTORMS TO MORE OF THE AREA. AT THIS TIME MODEL SOUNDINGS SUGGEST STORMS WILL BE NOT BE PARTICULARLY STRONG WITH MODERATE INSTABILITY AND VERTICAL WIND SHEAR. THE UPPER TROUGH SHOULD CLEAR THE AREA BY FRI EVENING LEAVING DRY WEATHER FOR THE WEEKEND. ECMWF AND GFS ARE BOTH SHOWING A COLD FRONT EARLY NEXT WEEK...BUT DIFFER ON ITS STRENGTH. GFS IS STRONGER. HAVE TRENDED TOWARD THE WEAKER ECMWF AND INCREASED TEMPS FOR MON AND TUE. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 64 81 63 79 61 / 10 10 10 20 40 AUSTIN BERGSTROM INTL AIRPORT 63 81 61 79 60 / 10 10 10 20 40 NEW BRAUNFELS MUNI AIRPORT 64 80 62 77 60 / 10 10 10 20 40 BURNET MUNI AIRPORT 63 80 61 77 61 / 10 10 10 20 40 DEL RIO INTL AIRPORT 67 83 67 78 64 / 20 10 30 40 50 GEORGETOWN MUNI AIRPORT 62 78 61 77 60 / 10 10 10 20 40 HONDO MUNI AIRPORT 65 82 64 77 62 / 10 10 20 40 50 SAN MARCOS MUNI AIRPORT 63 80 62 78 60 / 10 10 10 20 40 LA GRANGE - FAYETTE REGIONAL 63 80 61 78 61 / 10 - 10 20 30 SAN ANTONIO INTL AIRPORT 66 81 64 77 63 / 10 10 10 30 50 STINSON MUNI AIRPORT 67 82 65 77 63 / 10 10 10 30 50 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...25 SYNOPTIC/GRIDS...01 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
635 PM CDT TUE MAR 27 2012 .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE EVENING. THE COMPLEX OF THUNDERSTORMS ACROSS THE BIG BEND REGION IS MAKING SLOW S/SW-WRD PROGRESS THIS EVENING. LATEST RUC ANALYSIS SUGGESTS THAT THE TSRA WILL CONTINUE TO MOVE SW-WRD THIS EVENING...BUT SHEAR APART/DISSIPATE BEFORE REACHING KDRT. HAVE THEREFORE OPTED TO MENTION CB AROUND KDRT LATER TONIGHT...BUT CONFIDENCE IS TOO LOW TO WARRANT EXPLICIT MENTION OF TSRA AT THE TERMINAL. OTHERWISE...SHRA/TSRA EARLIER THIS AFTERNOON ACROSS THE RIO GRANDE PLAINS AND ADJACENT AREAS IS RAPIDLY TRENDING DOWNWARD AND SHOULD CONTINUE TO DO SO WITH THE LOSS OF DAYTIME HEATING. ANTICIPATE ANOTHER ROUND OF MVFR STRATUS AOB 2KFT TO SETTLE IN ALONG THE I-35 CORRIDOR BY ABOUT 06Z. CIGS WILL LOWER AND SPREAD WEST OVERNIGHT...WITH LIFR CIGS POSSIBLE AT KAUS/KSAT/KSSF IN THE NEAR-DAYBREAK HOURS. SIMILAR TO TODAY...CONDITIONS WILL BE SLOW TO IMPROVE...BUT VFR CONDITIONS WILL RETURN AROUND/AFTER 18Z. && .PREV DISCUSSION... /ISSUED 331 PM CDT TUE MAR 27 2012/ DISCUSSION... THE SOUTHERN PLAINS SITS UNDER THE BACKSIDE OF AN UPPER LEVEL RIDGE FROM 700-250MB THIS AFTERNOON. WE ARE BEGINNING TO SEE A SLOW SHIFT IN THE PATTERN. HEIGHTS HAVE FALLEN SLIGHTLY OVER THE PAST DAY. THIS COMBINED WITH STRONG HEATING OVER THE MOUNTAINS IN NORTHERN MEXICO IS ALLOWING THUNDERSTORMS TO FORM. SIMILAR TO LAST NIGHT EXPECT STORMS THROUGH THE EVENING...BUT QUESTION IS WHETHER THEY CAN MAKE ACROSS THE PLAINS INTO TX. ATMOSPHERE IS FAIRLY CAPPED OVER OUR CWA...SO HAVE ONLY SLIGHT CHANCE POPS OVER THE WESTERN THIRD OF THE AREA. ANY STORMS THAT DO MAKE IT ACROSS MAY BE STRONG WITH SMALL HAIL AND GUSTY WINDS. WED LOOKS VERY SIMILAR TO TODAY WITH PERHAPS A LITTLE BETTER CHANCE OF STORMS MAKING ACROSS NORTHERN MEXICO INTO TX. THU THE UPPER TROUGH WHICH IS OVER THE WEST COAST WILL APPROACH TX AND THIS WILL BRING A BETTER CHANCE FOR THUNDERSTORMS TO MORE OF THE AREA. AT THIS TIME MODEL SOUNDINGS SUGGEST STORMS WILL BE NOT BE PARTICULARLY STRONG WITH MODERATE INSTABILITY AND VERTICAL WIND SHEAR. THE UPPER TROUGH SHOULD CLEAR THE AREA BY FRI EVENING LEAVING DRY WEATHER FOR THE WEEKEND. ECMWF AND GFS ARE BOTH SHOWING A COLD FRONT EARLY NEXT WEEK...BUT DIFFER ON ITS STRENGTH. GFS IS STRONGER. HAVE TRENDED TOWARD THE WEAKER ECMWF AND INCREASED TEMPS FOR MON AND TUE. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 64 81 63 79 61 / 10 10 10 20 40 AUSTIN BERGSTROM INTL AIRPORT 63 81 61 79 60 / 10 10 10 20 40 NEW BRAUNFELS MUNI AIRPORT 64 80 62 77 60 / 10 10 10 20 40 BURNET MUNI AIRPORT 63 80 61 77 61 / 10 10 10 20 40 DEL RIO INTL AIRPORT 67 83 67 78 64 / 20 10 30 40 50 GEORGETOWN MUNI AIRPORT 62 78 61 77 60 / 10 10 10 20 40 HONDO MUNI AIRPORT 65 82 64 77 62 / 10 10 20 40 50 SAN MARCOS MUNI AIRPORT 63 80 62 78 60 / 10 10 10 20 40 LA GRANGE - FAYETTE REGIONAL 63 80 61 78 61 / 10 - 10 20 30 SAN ANTONIO INTL AIRPORT 66 81 64 77 63 / 10 10 10 30 50 STINSON MUNI AIRPORT 67 82 65 77 63 / 10 10 10 30 50 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...25 SYNOPTIC/GRIDS...01 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1053 PM CDT TUE MAR 27 2012 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND WEDNESDAY. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE MOVING NE OVER FAR NORTHERN MINNESOTA...AND ITS ASSOCIATED COLD FRONT NOW CROSSING THE MINNESOTA/WISCONSIN BORDER. NO PRECIP ALONG THE COLD FRONT SO FAR THROUGH EARLY THIS AFTERNOON WHERE TEMPERATURES HAVE RISEN INTO THE MIDDLE TO UPPER 60S OVER WESTERN WISCONSIN. MUCH COOLER OVER NE WISCONSIN WHERE CLOUD COVER HAS KEPT TEMPERATURES IN THE 40S AND 50S. THE BIGGEST STORY SO FAR HAS BEEN THE GUSTY WINDS...WHICH SEEM TO BE PEAKING ABOUT NOW. HAVE SEEN SEVERAL REPORTS ALONG THE LAKESHORE FROM SHEBOYGAN TO SISTER BAY OF GUSTS TO 45 MPH...AND A FEW REPORTS IN THE 50S AT THE KEWAUNEE AND ALGOMA MARINE STATIONS. INLAND LOCATIONS HAVE BEEN CONSISTENTLY GUSTING BETWEEN 35 AND 40 MPH. HAVE BEEN TREATING THE STRONG GUSTY WINDS ALONG THE LAKESHORE AS A LOCALIZED PHENOMENA...AND USING SPS/S TO HIGHLIGHT THE THREAT. BEHIND THE FRONT...SEE A PRETTY SOLID STRATO-CU DECK OVER MINNESOTA AND THE DAKOTAS WITHIN A COLDER AIRMASS. FORECAST CONCERNS INCLUDE WIND THROUGH THE EVENING...THEN CLOUDS AND TEMPS. TONIGHT...OCCLUDED LOW PRESSURE OVER NORTHERN MINNESOTA WILL TRACK ENE ACROSS NORTHERN LAKE SUPERIOR TONIGHT. ASSOCIATED COLD FRONT WILL DROP ACROSS THE SE 2/3RDS OF THE FORECAST AREA THIS EVENING...SHIFTING OUR WINDS FROM THE SOUTH TO THE WEST. WILL PROBABLY SEE GUSTY WINDS ALONG THE LAKESHORE THROUGH EARLY THIS EVENING AND SHOULD DIMINISH THEREAFTER ONCE THE FRONT MOVES THROUGH. AM TEMPTED TO PULL OUT POPS TONIGHT GIVEN A LACK OF INSTABILITY AND CU OF LITTLE VERTICAL EXTENT UPSTREAM. WILL WAIT UNTIL THE LAST MINUTE TO LOOK AT THE LATEST TRENDS BEFORE YANKING POPS OUT. SHOULD SEE A PERIOD OF CLEARING WORK ACROSS THE AREA ALONG AND BEHIND THE FRONT BEFORE WRAP AROUND STRATO-CU DIVES IN FROM NW TO SE. DEEPER MOISTURE OVER LAKE SUPERIOR AND THE UPPER PENINSULA COMBINED WITH UPSLOPE FLOW MAY LEAD TO SCT SHOWER ACTIVITY OVER N-C WISCONSIN AS THE STRATO-CU WORKS INTO THE AREA. OTHERWISE...DRY CONDITIONS ARE EXPECTED ELSEWHERE UNDER COLD ADVECTION. LOWS RANGING FROM THE UPPER 30S NORTH TO MIDDLE 40S SOUTH. WEDNESDAY...CYCLONIC FLOW WILL HANG AROUND WITH NW WINDS COLD ADVECTING THE ENTIRE DAY. STEEP LOW LEVEL LAPSE RATES COMBINED WITH AMPLE MOISTURE UP TO AROUND 800MB SUPPORTS A WIDESPREAD BKN/OVC STRATO-CU FIELD HANGING AROUND THROUGH THE AFTERNOON. SCT LIGHT SHOWER ACTIVITY WILL LIKELY CONTINUE THROUGH AT LEAST THE MORNING HOURS OVER N-C WISCONSIN. LOOKED INTO SNOW POSSIBILITIES...BUT MOISTURE DOES NOT LOOK LIKE IT WILL EXTEND HIGH ENOUGH INTO THE COLD AIR FOR SNOWFLAKES TO BE INTRODUCED INTO THE CLOUDS. WITH COLD ADVECTION AND CLOUD COVER...KNOCKED A DEGREE OR TWO OFF THE HIGH TEMPS...WHICH WOULD PLACE THEM INTO THE LOWER 40S NORTH TO MIDDLE 50S SOUTH. .LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY. FROST AND FREEZE POTENTIAL CERTAINLY THERE FOR WEDNESDAY NIGHT AS SURFACE HIGH DRIFTS BY TO THE NORTH AND UPPER RIDGE APPROACHES FROM THE NORTHERN PLAINS. RECORD WARMTH EARLIER THIS MONTH HAS STARTED THE DEVELOPMENT OF SOME VEGETATION WHICH MAY BE THREATENED BY THIS FROST OR FREEZE. THEN A RATHER ACTIVE PERIOD OF WEATHER EXPECTED WITH SOME RATHER ABRUPT SWINGS POSSIBLE LATER THIS WEEK AND EARLY NEXT WEEK AS HIGH AMPLITUDE NEGATIVELY TILTED TROUGH FORECAST TO LIFT NORTHEAST FROM THE SOUTHERN AND CENTRAL PLAINS. TWO MUCH WEAKER UPPER TROUGHS MOVE BY THURSDAY NIGHT AND EARLY FRIDAY AND AGAIN SATURDAY. THESE SHOULD PRODUCE SOME SHOWERS AND ELEVATED THUNDERSTORMS IN THE SOUTH AND RAIN OR SNOW SHOWERS IN THE NORTH. UPPER RIDGE SHARPENS SATURDAY AND SUNDAY AND SHOULD RESULT IN MORE VERY WARM TEMPERATURES SATURDAY SUNDAY AND MONDAY. A WARM FRONT LIFTING NORTH SUNDAY COULD BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS WITH SOME POSSIBILITY OF MARGINALLY SEVERE HAIL. DEEPENING SURFACE LOW MOVING FROM THE CENTRAL PLAINS TO NORTHERN WISCONSIN SHOULD BRING 60F DEW POINTS INTO SOUTHERN WISCONSIN WITH POSSIBLE SEVERE STORMS AS TRIPLE POINT LOW MOVES ACROSS THE AREA. THEN SHARPLY COLDER TUESDAY WITH RAIN AND SNOW SHOWERS. && .AVIATION...A COLD FRONT WAS MOVG THROUGH NE/EC WI LATE THIS EVG. STRONG WEST WINDS WERE STILL OCCURRING BEHIND THE FRONT...WITH OCCASIONAL GUSTS TO 30-40 KTS. GIVEN THE GUSTINESS THAT IS OCCURRING... HAVE OPTED TO REMOVE THE MENTION OF LLWS...AND JUST KEEP GUSTS TO 30S KTS IN THE TAFS FOR THE OVERNIGHT PERIOD. WIDESPREAD STRATOCUMULUS CLOUDS COVERED NORTHERN WI...AND SHOULD SAG FARTHER SOUTH LATE TONIGHT INTO WEDS...AS WINDS TURN MORE NORTHWEST. CIGS WILL PROBABLY DROP TO MVFR OVER NC/C/FAR NE WI LATER TONIGHT INTO WEDS MORNING. STRATUCUMULUS SHOULD REMAIN OVER MUCH OF THE FORECAST AREA ON WEDNESDAY...THOUGH VFR CONDITIONS SHOULD BE FOUND AT MOST LOCATIONS BY MIDDAY. A FEW LIGHT SHOWERS MAY BRUSH ACROSS FAR NORTHERN WI LATE TONIGHT INTO WEDNESDAY. EXPECT CLEARING TO OCCUR ON WEDS EVG...AS HIGH PRESSURE MOVES INTO THE REGION. KIECKBUSCH && .MARINE...THOUGH STABILITY WILL BE INCREASING LATER THIS AFTERNOON...STRONG SOUTHEAST TO SOUTH WINDS CONTINUE TO IMPACT THE LAKESHORE WITH GUSTS MEASURED BETWEEN 45 AND 50 KTS AT KEWAUNEE AND ALGOMA. SINCE IMPACTS FROM STABILITY HAVE BEEN NON-EXISTENT SO FAR...WILL EXTEND THE GALE WARNING THROUGH 03Z AFTER COORDINATION WITH OFFICES TO THE SOUTH. ONCE THE GALE IS OVER...WINDS WILL SWING AROUND TO THE WEST BEHIND A COLD FRONT THIS EVENING AND DIMINISH...THOUGH A SMALL CRAFT ADVISORY WILL BE NEEDED DUE LINGERING WAVES THROUGH THE REST OF THE NIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1029 PM CDT TUE MAR 27 2012 .UPDATE... 23Z HRRR AND LOCAL 4 KM WRF SHOWED THE NORTHERN ILLINOIS SHOWERS/THUNDERSTORMS. MODELS NOT SHOWING ANY MORE DEVELOPMENT ACROSS SOUTHERN WISCONSIN. STILL SOME ELEVATED CAPE TO LIFTING FROM AROUND 4 THSD FT OVER PORTIONS OF SOUTH CENTRAL AND SOUTHEAST WISCONSIN OFF LATEST 01Z RUC SOUNDING. SOME LOW LEVEL UPWARD MOTION BUT RATHER STRONG MID LEVEL SUBSIDENCE AND DRY AIR LIKELY CAUSING TOO MUCH ENTRAINMENT IN ANY CUMULUS. ALSO MUCH OF THE CUMULUS HAS DISSIPATED WITH LOSS OF HEATING. WINDS HAVE DIMINISHED SOMEWHAT BUT STILL SOME GUST POTENTIAL TO 25 MPH AT TIMES WITH THE WEAK COLD AIR ADVECTION AND PRESSURE GRADIENT FROM LOW OVER NORTHERN LAKE SUPERIOR. && .AVIATION/06Z TAFS/... SOME LOW LEVEL WIND SHEAR POTENTIAL AS WINDS AT THE SURFACE DIMINISH IN LOW AREAS. HOWEVER MOST AREAS WILL HAVE SURFACE WINDS IN THE 10 TO 15 KNOT RANGE. VFR EXPECTED WITH SOME SCATTERED CUMULUS AROUND 4 THSD FT. EXPECT THUNDERSTORMS TO REMAIN TO THE SOUTH OF WISCONSIN. POTENTIAL FOR THE STRATOCUMULUS SHIELD AROUND THE STRONG LOW TO PUSH SOUTH INTO PORTIONS OF SOUTH CENTRAL AND SOUTHEAST WISCONSIN WEDNESDAY. MAINLY VFR CIGS EXPECTED EVEN IF THIS DOES PUSH SOUTH. && .MARINE... WINDS HAVE DIMINISHED BELOW GALES BUT A BRISK SOUTHWEST WIND WILL BECOME WEST ON WEDNESDAY. SMALL CRAFT ADVISORIES ARE IN EFFECT TONIGHT AND WEDNESDAY. .PREV DISCUSSION... /ISSUED 337 PM CDT TUE MAR 27 2012/ VERY SHORT TERM...TONIGHT AND WEDNESDAY. TONIGHT - CONFIDENCE...MEDIUM POTENT/COMPACT 46 UNIT VORT MAX ROTATING NORTHEAST INTO CANADA. ANY VORTICITY ADVECTION THIS FAR SOUTH IS QUITE CHANNELIZED AND LITTLE CONTRIBUTION TO VERTICAL MOTION. IN THE LOWER LEVELS...CORE OF STRONG 850 JET PEELS EAST THIS EVENING. GUSTS HAVE BEEN NEARING THE ADVISORY CRITERIA AT TIMES. WILL BE CLOSE IN SOME AREAS BUT WILL HOLD OFF ON ISSUANCE AT THIS POINT. SURFACE MOIST AXIS LEANING INTO CWA AHEAD OF COLD FRONT. BEST INSTABILITY HAS BEEN SOUTH PER SPC MESO ANALYSIS. SOME DESTABILIZATION EXPECTED INTO SRN WI. HOWEVER BETTER DEW POINTS ARE POOLING TO OUR SOUTH WITH MOIST AXIS GETTING PINCHED A BIT INTO SW WI. SOME LOW LEVEL CONVERGENCE COULD STILL INITIATE A CELL OR TWO INTO THE EARLY EVENING HOURS. CU THUS FAR HAS BEEN WELL CAPPED BUT WATCHING SW/SC WI IN EXISTING CU FIELD FOR ANY POSSIBLE DEVELOPMENT. THE HRRR IS SUGGESTING SOME ISOLATED DEVELOPMENT. MAXES LIKELY TO BE REACHED THIS EVENING AS 70S READY TO SPILL INTO SC WI. SOME MODIFICATION IN THE EAST WITH LOSS OF HEATING BUT STILL AN EVENING MAX LIKELY. WEDNESDAY - CONFIDENCE...MEDIUM LINGERING 500 MILLIBAR CYCLONIC FLOW EARLY GRADUALLY GIVES WAY TO MORE RIDGING WITH TIME. SURFACE HIGH ALSO DRAWS CLOSER AS THE DAY WEARS ON HELPING TO EASE BACK ON THE WINDS A BIT. CU RULE POINTS TO GREATER COVERAGE CU IN THE NE CWA...PER COMBO OF RH PROGS...BUFKIT...PROGGD PROXIMITY OF UPPER CYCLONIC FLOW. SHORT TERM...WEDNESDAY NIGHT THROUGH FRIDAY NIGHT. WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH. UPPER RIDGING KEEPS THIS PERIOD DRY. UPPER LEVEL NORTHWEST FLOW WITH COLD ADVECTION DROPPING 850 MB AND 925 MB TEMPERATURES INTO THE SINGLE DIGITS ABOVE 0C...WITH 0C OR BELOW ACROSS THE NORTHEAST. LIGHT WINDS AND CLEAR SKIES WITH HIGH PRESSURE OVERHEAD LEADS TO LOWS IN THE LOWER TO MIDDLE 30S. KEEPING THE AREAS OF FROST IN THE COLDEST LOCATIONS WITH PATCHY FROST ELSEWHERE. DRY AIR STREAMS INTO REGION WITH PERSISTENT NORTHEAST TO EAST FLOW AROUND HUDSON BAY HIGH...WITH LOW TO MID 20 DEW POINTS IN THE EAST AND LOW TO MID 30S WEST. SOME UPWARD MODIFICATION OF 925 MB TEMPERATURES BRINGS UPPER 50S HIGH IN THE FAR SOUTHWEST...WITH LOW TO MID 50S ELSEWHERE EXCEPT MID TO UPPER 40S IN THE FAR EAST NEARER THE LAKE. THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE MEDIUM. SOME TIMING CONCERNS RELATED TO DIFFERING CONFIGURATIONS AMONG MODELS WITH TROUGH CROSSING THE WESTERN GREAT LAKES. HAVE DIVIDED POPS THIS PERIOD INTO 6-HOURLY GROUPS TO HIGHLIGHT THE 06Z TO 18Z FRIDAY TIME FRAME AS MOST LIKELY FOR PRECIPITATION. CLOUDS...PRECIPITATION THAT WILL BE MAINLY SHOWERS...AND EASTERLY FLOW AROUND WEAK SURFACE LOW PASSING SOUTH WILL KEEP HIGH TEMPERATURES SIMILAR TO THURSDAY. LONG TERM...SATURDAY THROUGH TUESDAY. FORECAST CONFIDENCE LOW TO MEDIUM. ANOTHER SHORT WAVE KEEPS POPS IN THE FORECAST FOR FRIDAY NIGHT...THEN ZONAL FLOW BUCKLES TO THE SOUTHWEST AHEAD OF DEEPENING WESTERN TROUGH. RISING TEMPERATURES INTO THE 60S FOR SATURDAY AND 70S SUNDAY...WITH MID TO UPPER 60S ALONG THE LAKE AND NORTHEAST. CYCLOGENESIS IN THE PLAINS SUNDAY AFTERNOON AND EVENING...WITH LOW CONTINUING TO DEEPEN AS IT MOVES TOWARD WESTERN GREAT LAKES BRINGING THE WARM AND BREEZY CONDITIONS. UPPER SYSTEM EITHER CUTS-OFF PER GFS...OR REMAINS AN OPEN WAVE PER LATEST ECMWF MONDAY NIGHT INTO TUESDAY...SO FOLLOWED CONSENSUS BLEND WHICH BRINGS CHANCES FOR SHOWERS AND/OR THUNDERSTORMS THROUGH THE REST OF THE EXTENDED...THOUGH NO ALL DAY RAINS...WITH TEMPERATURES COOLING INTO THE 50S FOR TUESDAY. AVIATION/00Z TAFS/...STILL LOOKS LIKE A MAINLY DRY AND VFR FROPA. CONVECTION ISOLATED AT BEST WITH ANY SVR POTENTIAL TO OUR SOUTH PER SWODY1. MAIN STORY WILL BE WINDY CONDITIONS WITH SOUTHWEST 850 JET GRADUALLY SHIFTING AWAY WITH WESTERLY JET TAKING HOLD POST FROPA. SUBSIDENCE TAKES HOLD SO EXPECT DECENT MIXING INTO THE EVENING HOURS EVEN AFTER PEAK MIXING DUE TO INSOLATION. COLD ADVECTION PLUS PROXIMITY TO FRINGE OF UPPER CYCLONIC SUGGESTS SOME CU DEVELOPMENT FOR WEDNESDAY...WITH GREATEST COVERAGE LIKELY IN NE CWA. MARINE...ASED ON TRENDS DECIDED TO EXTEND THE GALE INTO THE EVENING HOURS AS LINGERING WARM SECTOR SOUTHWEST 850/925 JET MAX GRADUALLY PEELS EAST. SMALL CRAFT ADVISORY WILL BE NEEDED ONCE THE GALE EXPIRES. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 6 PM CDT WEDNESDAY FOR LMZ643>646. && $$ UPDATE...HENTZ TONIGHT/WEDNESDAY AND AVIATION/MARINE...COLLAR WEDNESDAY NIGHT THROUGH TUESDAY...REM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
659 PM CDT TUE MAR 27 2012 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND WEDNESDAY. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE MOVING NE OVER FAR NORTHERN MINNESOTA...AND ITS ASSOCIATED COLD FRONT NOW CROSSING THE MINNESOTA/WISCONSIN BORDER. NO PRECIP ALONG THE COLD FRONT SO FAR THROUGH EARLY THIS AFTERNOON WHERE TEMPERATURES HAVE RISEN INTO THE MIDDLE TO UPPER 60S OVER WESTERN WISCONSIN. MUCH COOLER OVER NE WISCONSIN WHERE CLOUD COVER HAS KEPT TEMPERATURES IN THE 40S AND 50S. THE BIGGEST STORY SO FAR HAS BEEN THE GUSTY WINDS...WHICH SEEM TO BE PEAKING ABOUT NOW. HAVE SEEN SEVERAL REPORTS ALONG THE LAKESHORE FROM SHEBOYGAN TO SISTER BAY OF GUSTS TO 45 MPH...AND A FEW REPORTS IN THE 50S AT THE KEWAUNEE AND ALGOMA MARINE STATIONS. INLAND LOCATIONS HAVE BEEN CONSISTENTLY GUSTING BETWEEN 35 AND 40 MPH. HAVE BEEN TREATING THE STRONG GUSTY WINDS ALONG THE LAKESHORE AS A LOCALIZED PHENOMENA...AND USING SPS/S TO HIGHLIGHT THE THREAT. BEHIND THE FRONT...SEE A PRETTY SOLID STRATO-CU DECK OVER MINNESOTA AND THE DAKOTAS WITHIN A COLDER AIRMASS. FORECAST CONCERNS INCLUDE WIND THROUGH THE EVENING...THEN CLOUDS AND TEMPS. TONIGHT...OCCLUDED LOW PRESSURE OVER NORTHERN MINNESOTA WILL TRACK ENE ACROSS NORTHERN LAKE SUPERIOR TONIGHT. ASSOCIATED COLD FRONT WILL DROP ACROSS THE SE 2/3RDS OF THE FORECAST AREA THIS EVENING...SHIFTING OUR WINDS FROM THE SOUTH TO THE WEST. WILL PROBABLY SEE GUSTY WINDS ALONG THE LAKESHORE THROUGH EARLY THIS EVENING AND SHOULD DIMINISH THEREAFTER ONCE THE FRONT MOVES THROUGH. AM TEMPTED TO PULL OUT POPS TONIGHT GIVEN A LACK OF INSTABILITY AND CU OF LITTLE VERTICAL EXTENT UPSTREAM. WILL WAIT UNTIL THE LAST MINUTE TO LOOK AT THE LATEST TRENDS BEFORE YANKING POPS OUT. SHOULD SEE A PERIOD OF CLEARING WORK ACROSS THE AREA ALONG AND BEHIND THE FRONT BEFORE WRAP AROUND STRATO-CU DIVES IN FROM NW TO SE. DEEPER MOISTURE OVER LAKE SUPERIOR AND THE UPPER PENINSULA COMBINED WITH UPSLOPE FLOW MAY LEAD TO SCT SHOWER ACTIVITY OVER N-C WISCONSIN AS THE STRATO-CU WORKS INTO THE AREA. OTHERWISE...DRY CONDITIONS ARE EXPECTED ELSEWHERE UNDER COLD ADVECTION. LOWS RANGING FROM THE UPPER 30S NORTH TO MIDDLE 40S SOUTH. WEDNESDAY...CYCLONIC FLOW WILL HANG AROUND WITH NW WINDS COLD ADVECTING THE ENTIRE DAY. STEEP LOW LEVEL LAPSE RATES COMBINED WITH AMPLE MOISTURE UP TO AROUND 800MB SUPPORTS A WIDESPREAD BKN/OVC STRATO-CU FIELD HANGING AROUND THROUGH THE AFTERNOON. SCT LIGHT SHOWER ACTIVITY WILL LIKELY CONTINUE THROUGH AT LEAST THE MORNING HOURS OVER N-C WISCONSIN. LOOKED INTO SNOW POSSIBILITIES...BUT MOISTURE DOES NOT LOOK LIKE IT WILL EXTEND HIGH ENOUGH INTO THE COLD AIR FOR SNOWFLAKES TO BE INTRODUCED INTO THE CLOUDS. WITH COLD ADVECTION AND CLOUD COVER...KNOCKED A DEGREE OR TWO OFF THE HIGH TEMPS...WHICH WOULD PLACE THEM INTO THE LOWER 40S NORTH TO MIDDLE 50S SOUTH. .LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY. FROST AND FREEZE POTENTIAL CERTAINLY THERE FOR WEDNESDAY NIGHT AS SURFACE HIGH DRIFTS BY TO THE NORTH AND UPPER RIDGE APPROACHES FROM THE NORTHERN PLAINS. RECORD WARMTH EARLIER THIS MONTH HAS STARTED THE DEVELOPMENT OF SOME VEGETATION WHICH MAY BE THREATENED BY THIS FROST OR FREEZE. THEN A RATHER ACTIVE PERIOD OF WEATHER EXPECTED WITH SOME RATHER ABRUPT SWINGS POSSIBLE LATER THIS WEEK AND EARLY NEXT WEEK AS HIGH AMPLITUDE NEGATIVELY TILTED TROUGH FORECAST TO LIFT NORTHEAST FROM THE SOUTHERN AND CENTRAL PLAINS. TWO MUCH WEAKER UPPER TROUGHS MOVE BY THURSDAY NIGHT AND EARLY FRIDAY AND AGAIN SATURDAY. THESE SHOULD PRODUCE SOME SHOWERS AND ELEVATED THUNDERSTORMS IN THE SOUTH AND RAIN OR SNOW SHOWERS IN THE NORTH. UPPER RIDGE SHARPENS SATURDAY AND SUNDAY AND SHOULD RESULT IN MORE VERY WARM TEMPERATURES SATURDAY SUNDAY AND MONDAY. A WARM FRONT LIFTING NORTH SUNDAY COULD BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS WITH SOME POSSIBILITY OF MARGINALLY SEVERE HAIL. DEEPENING SURFACE LOW MOVING FROM THE CENTRAL PLAINS TO NORTHERN WISCONSIN SHOULD BRING 60F DEW POINTS INTO SOUTHERN WISCONSIN WITH POSSIBLE SEVERE STORMS AS TRIPLE POINT LOW MOVES ACROSS THE AREA. THEN SHARPLY COLDER TUESDAY WITH RAIN AND SNOW SHOWERS. && .AVIATION...S-SW WINDS WERE OCCURRING IN ADVANCE OF COLD FRONT OVER NE/EC WI...AND WERE QUITE GUSTY FROM THE WEST ACROSS NC/C WI IN THE WAKE OF THE FRONT. GUSTS TO 30-40 KTS ARE EXPECTED TO CONTINUE INTO THE EARLY EVG...ALONG AND JUST BEHIND THE FRONT. STRONG WINDS ALOFT WILL PRODUCE SOME MARGINAL LLWS FOR MUCH OF THE NIGHT. CLOUDS HAVE DISSIPATED AHEAD OF THE FRONT...AND THERE ARE NO INDICATIONS THAT ANY SHOWERS OR TSTMS WILL DEVELOP ALONG THIS BOUNDARY. WIDESPREAD WRAP-AROUND CLOUDS COVERED THE NORTHERN HALF OF MN AND NW WI...AND WILL MOVE OVER MUCH OF NC/C/FAR NE WI TONIGHT. CIGS MAY DROP TO MVFR OVER C/NC WI LATER TONIGHT INTO WEDS MORNING. WIDESPREAD STRATUCUMULUS SHOULD REMAIN OVER MUCH OF THE FORECAST AREA ON WEDNESDAY...THOUGH VFR CONDITIONS SHOULD BE FOUND AT MOST LOCATIONS BY LATE MORNING. A FEW LIGHT SHOWERS MAY BRUSH ACROSS FAR NORTHERN WI LATER TONIGHT INTO WEDNESDAY. KIECKBUSCH && .MARINE...THOUGH STABILITY WILL BE INCREASING LATER THIS AFTERNOON...STRONG SOUTHEAST TO SOUTH WINDS CONTINUE TO IMPACT THE LAKESHORE WITH GUSTS MEASURED BETWEEN 45 AND 50 KTS AT KEWAUNEE AND ALGOMA. SINCE IMPACTS FROM STABILITY HAVE BEEN NON-EXISTENT SO FAR...WILL EXTEND THE GALE WARNING THROUGH 03Z AFTER COORDINATION WITH OFFICES TO THE SOUTH. ONCE THE GALE IS OVER...WINDS WILL SWING AROUND TO THE WEST BEHIND A COLD FRONT THIS EVENING AND DIMINISH...THOUGH A SMALL CRAFT ADVISORY WILL BE NEEDED DUE LINGERING WAVES THROUGH THE REST OF THE NIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
259 PM CDT MON MAR 26 2012 .SHORT TERM...TONIGHT AND TUESDAY. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE CENTERED OVER NORTHERN WYOMING AND A WARM FRONT EXTENDING ACROSS SOUTH DAKOTA INTO IOWA. NORTH OF THE WARM FRONT...AND ALONG THE 850MB FRONT...LIGHT SHOWERS CONTINUE TO FALL OUT OF A 9KFT DECK OVER WESTERN AND SOUTHERN WISCONSIN. HARD TO SAY IF ANY OF THESE SHOWERS ARE REACHING THE GROUND OVER CENTRAL WISCONSIN...THOUGH RUC SOUNDINGS SHOW A LARGE DRY WEDGE CENTERED AROUND 850MB THAT WOULD INDICATE MOSTLY VIRGA. FARTHER WEST...ADDITIONAL SHOWER ACTIVITY HAS BEEN DEVELOPING OVER THE NORTHERN PLAINS IN CLOSER PROXIMITY TO THE LOW LEVEL JET AND MOISTURE CONVERGENCE. AS THIS LLJ AND 850MB WARM FRONT MOVE NE OVER THE AREA TONIGHT...PRECIP CHANCES AND PRECIP TYPE REMAIN THE PRIMARY FORECAST CONCERNS. TONIGHT...CHALLENGING FORECAST TONIGHT NO MATTER WHICH WAY YOU SLICE IT. STRONG SHORTWAVE OVER THE ROCKIES WILL LIFT NE ACROSS THE NORTHERN PLAINS TONIGHT. AHEAD OF THE WAVE...AN ALREADY POTENT LLJ WILL CRANK UP TO 60-70KTS OVER THE NORTHERN MISSISSIPPI VALLEY DURING THE EVENING. AS THE LLJ STRENGTHENS...MOISTURE CONVERGENCE WILL RAMP UP ON THE 300K SURFACE OVER NORTHERN MINNESOTA...WESTERN LAKE SUPERIOR...AND NORTHERN WISCONSIN BY LATE IN THE EVENING. THINK WE WILL SEE A WARM AIR ADVECTION WING DEVELOP IN THIS AREA BY MIDNIGHT...WITH PRECIP MOVING INTO NORTHERN AND POSSIBLY CENTRAL WISCONSIN. ADMITTEDLY SOME UNCERTAINTY EXISTS WITH THE TIMING OF THIS PRECIP...DUE TO THE VERY DRY AND SHALLOW POLAR AIRMASS THAT WILL REMAIN IN PLACE. HAVE BACKED OFF A LITTLE ON THE PRECIP ARRIVAL. THIS PRECIP SHOULD THEN LIFT NE THROUGH THE OVERNIGHT PERIOD AS THE LLJ VEERS. BUT THE MAIN UNCERTAINTY REVOLVES AROUND PTYPE. THERMAL RIDGING OVER THE NORTHERN PLAINS WILL SPREAD EAST TONIGHT WHICH MODELS PROJECT CREATES A LARGE WARM NOSE IN THE THERMAL PROFILE CENTERED AROUND 800MB. WITH TEMPS IN THIS WARM NOSE INCREASING TO 6-7C...PRECIP WILL TURN TO ALL LIQUID IN THIS LAYER OVERNIGHT. THE UNCERTAINTY WILL REVOLVE AROUND SURFACE TEMPS AS THE SHALLOW POLAR AIRMASS LINGERS. CLOUD COVER WILL BE INCREASING THROUGH THE EVENING WHERE AFTERNOON TEMPS WILL TOP OUT IN THE MID 40S. HOWEVER...THE AIRMASS IS ALSO QUITE DRY RESULTING IN WET BULB TEMPS MOSTLY BELOW FREEZING OVER NORTH-CENTRAL WISCONSIN FOR MUCH OF THE NIGHT. PRECIP WILL BE TRANSIENT...BUT POTENTIAL WILL BE THERE FOR FREEZING RAIN FOR A FEW HOURS. IF TEMPS ONLY FALL TO 31 OR 32 DEGREES...ANY FREEZING RAIN MAY NOT HAVE MUCH IMPACT DUE TO WARM GROUND TEMPERATURES. WITH THE UNCERTAINTY OF SURFACE TEMPS AND IMPACTS...WILL NOT ISSUE A HEADLINES...THOUGH POTENTIAL WILL BE THERE FOR ONE. A FEW RUMBLES OF THUNDER WILL ALSO BE POSSIBLE DUE TO ELEVATED CAPES REACHING OVER 200 J/KG. TUESDAY...850MB WARM FRONT AND ASSOCIATED MID-LEVEL FGEN WILL LIFT OFF TO THE NORTHEAST SHORTLY AFTER 12Z AND MID/UPPER LEVEL DRYING WILL ARRIVE ABOVE 700MB. PROGGED SOUNDINGS REMAIN FAIRLY MOIST BETWEEN 900-700MB...SO THINKING MAYBE ONLY A FEW SHOWERS WILL REMAIN ONCE THE FGEN INDUCED PRECIP EXITS. UPPER LEVEL FRONT TIED TO THE SHORTWAVE OVER THE NORTHERN PLAINS WILL MAKE HEADWAY ACROSS THE AREA TOMORROW AFTERNOON. PROGGED SOUNDINGS INDICATE THAT THE AREA WILL REMAIN CAPPED FOR CONVECTION...BOTH ELEVATED AND AT THE SURFACE. THE SURFACE WARM FRONT MAY SNEAK INTO CENTRAL WISCONSIN LATE IN THE AFTERNOON BUT STILL CAN ONLY FIND CAPPING. SO IN THE END...NOT EXPECTING THAT MUCH TO HAPPEN TOMORROW. .LONG TERM...TUESDAY NIGHT THROUGH NEXT MONDAY. A FEW SHOWERS POSSIBLE TUESDAY NIGHT AND WEDNESDAY AS A WEAK UPPER TROUGH PASSES THROUGH. THEN A CANADIAN HIGH DROPS DOWN TOWARDS THE EASTERN GREAT LAKES AND BRINGS DRIER AND SOMEWHAT COOLER AIR INTO OUR AREA. A FROST OR FREEZE LOOKS LIKELY EXCEPT ALONG THE IMMEDIATE BAY AND LAKE THURSDAY MORNING. THIS WOULD NORMALLY NOT BE MENTIONED AT THIS TIME OF YEAR BUT THE RECORD WARMTH OF MARCH HAS CAUSED MANY FRUIT TREES TO BLOSSOM AND ORCHARD OWNERS HAVE REQUESTED THAT WE MENTION IN THE FORECAST. THE SURFACE HIGH RETREATS THURSDAY NIGHT AS UPPER FLOW BECOMES NEARLY ZONAL AND JET ENERGY APPROACHES FROM THE PLAINS STATES. AN ASSOCIATED SURFACE TROUGH SHOULD BRING SOME SHOWERS AND ELEVATED THUNDERSTORMS LATE THURSDAY NIGHT AND FRIDAY AS IT MOVES THROUGH THE REGION. WARMER WEATHER EXPECTED FOR SATURDAY AND PALM SUNDAY WITH A CHANCE OF THUNDERSTORMS. THE MODELS HAVE BIG DIFFERENCES BY THE MIDDLE OF NEXT WEEK AND ARE COMPLETELY OUT OF PHASE WITH EACH OTHER MUCH OF THE TIME. BELIEVE THIS IS DUE TO A POSSIBLE PATTERN CHANGE TO RIDGING OVER ALASKA AND THE POSSIBLE ESTABLISHMENT OF A POLAR VORTEX OVER THE GREAT LAKES BY THE SECOND WEEK OF APRIL. && .AVIATION...CANADIAN HIGH PRESSURE WILL RETREAT TO THE NORTHEAST WHILE A WARM FRONT OVER THE NORTHERN PLAINS WILL MOVE NORTHEAST ACROSS THE REGION TONIGHT INTO TUESDAY MORNING. LIGHT SHOWER ACTIVITY OVER WESTERN WISCONSIN WILL SHIFT ACROSS CENTRAL AND NORTHERN WISCONSIN ALONG THE FRONT TONIGHT. WILL SEE INCREASING CLOUDS THIS AFTERNOON AND EARLY THIS EVENING BEFORE PRECIP ARRIVES. PRECIP TYPE IS UNCERTAIN...MAINLY DUE TO THE NEAR SURFACE TEMPERATURES AS COOLING TAKES PLACE TONIGHT. FORECAST MODELS PROJECT TEMPS FALLING TO JUST BELOW FREEZING...THOUGH INCOMING CLOUD COVER MAY KEEP TEMPS SLIGHTLY HIGHER THAN THE MODELS PREDICT. AS A RESULT...THINK FREEZING RAIN AND SLEET IS POSSIBLE OVER NORTHERN WISCONSIN TONIGHT...THOUGH IMPACTS MAY TURN OUT TO BE MINIMAL DUE TO SURFACE TEMPS SO CLOSE TO FREEZING. THE PRECIP WILL PULL OUT LATE TONIGHT...WHICH WILL LEAVE MVFR CIGS OVER CENTRAL AND NORTH-CENTRAL WISCONSIN FOR MUCH OF TUESDAY MORNING. MPC && .MARINE...INCREASING SOUTHEAST WINDS EXPECTED TONIGHT AS LLVL FLOW INCREASES TO 45KTS AT 950MB. DESPITE WARM AIR ADVECTION CENTERED AROUND 800MB... HAVE CONCERNS THAT THE SHALLOW CANADIAN AIRMASS WILL KEEP THE BL A LITTLE MORE MIXY THAN PREVIOUS THINKING THROUGH ABOUT MIDDAY ON TUESDAY. AS A RESULT...THINK LOW END GALES ARE A POSSIBILITY ALONG THE LAKE MICHIGAN SHORELINE. SHOULD SEE STABILITY BECOME A BIG FACTOR TUESDAY AFTERNOON AND WINDS SUBSIDING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MPC/RDM
AREA FORECAST DISCUSSION...CORRECTED FOR TONIGHT PCPN POTENTIAL
NWS LA CROSSE WI
230 PM CDT MON MAR 26 2012 .SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT 230 PM CDT MON MAR 26 2012 FORECAST CONCERNS FOCUS ON POTENTIALLY STRONG WINDS...STORM AND GRADIENT RELATED...TUE/TUE NIGHT. A UPPER LEVEL SHORTWAVE TROUGH WAS DRIVING ACROSS THE SOUTHERN ROCKIES...PER LATEST WATER VAPOR SATELLITE IMAGERY...WITH THE 26.12Z NAM AND GFS TAKING THIS FEATURE ACROSS NORTHERN MN BY 00Z WED. THE SYSTEM COMES IN STACKED WITH ITS ASSOCIATED SFC LOW...TAKING ITS NORTH-SOUTH COLD FRONT TO THE MISSISSIPPI RIVER BY 18-21Z TUE...AND THEN ACROSS EASTERN WI BY 03Z WED. BEFORE THE HEART OF THIS WEATHER SYSTEM MOVES IN THERE WILL BE STRONG LOW LEVEL 925-850 MB WARM AIR ADVECTION ACROSS THE REGION TONIGHT INTO TUE MORNING...ALONG WITH ADVECTION ON THE ISENTROPIC SFCS. STRONG 850 MB MOISTURE TRANSPORTS AHEAD OF THE FRONT...WITH A 60+ KT LOW LEVEL JET NOSING INTO NORTHERN MN TONIGHT...AND CONTINUING TO POINT TO FAR NORTHERN PORTIONS OF THE REGION. HOWEVER...SATURATION COULD BE A CONCERN A NORTH-SOUTH RUNNING X-SECTIONS AND BUFKIT SOUNDINGS KEEPS THE DEEPER MOISTURE FARTHER NORTH...WITH SATURATION CONFINED UNDER 700 MB FOR THE SOUTHERN 1/2 OF THE FORECAST AREA. THE COMBINATION OF THE LOW LEVEL THERMODYNAMICS...LOW LEVEL JET/MOISTURE TRANSPORT...AND DEEPER SATURATION MAKES PCPN MORE LIKELY ACROSS THE NORTHERN REACHES OF THE REGION TONIGHT. LOCALLY...MOSTLY NORTH OF A WABASHA MN TO BLACK RIVER FALLS WI LINE. HOWEVER...CURRENT 88-D IMAGERY HAS AN EXPANDING BAND OF SHOWERS WHICH HAVE BLOSSOMED ON THE LEADING EDGE OF THE LOWER LEVEL MOISTURE TRANSPORT. RUC13 WOULD SLIDE THIS BAND OF PCPN ACROSS THE FORECAST AREA THIS EVENING...WITH THE MAIN PCPN FOCUS THEN TURNING FARTHER NORTH. WILL WORK PCPN CHANCES WITH THIS IN MIND TUESDAY THE FRONT WILL BE MOVING ACROSS THE AREA...BUT NOT A LOT OF FRONTOGENETIC LIFT ACCORDING TO THE NAM/GFS. SOME MUCAPE OF 250-500 J/KG WORKS INTO NORTHEAST IA/SOUTHWEST WI AHEAD OF THE BOUNDARY. 0-3 KM SHEAR CONTINUES TO BE STRONG AT 40-45 KTS FROM THE WEST. BUFKIT SOUNDINGS INDICATE SOME DRYING IN THE SUB CLOUD LAYER...INVERTED-V SHAPE. EXPECT SOME SHOWERS TO STORMS TO DEVELOP ALONG AND JUST AHEAD OF THE FRONT...AND IF ANY WOULD BECOME STRONG TO SEVERE...DAMAGING WINDS WOULD BE THE MAIN CONCERN. EVEN PERKY SHOWERS WILL BE ABLE TO ACCELERATE SOME WIND TO THE SFC...WITH 40 MPH WIND GUSTS CERTAINLY POSSIBLE. SPEAKING OF THE WINDS...THE PRESSURE GRADIENT WILL CONTINUE TO TIGHTEN TONIGHT...STAYING THAT WAY INTO TUESDAY NIGHT. 60 KT WINDS BY 2000 FT...BUT ABOVE THE INVERSION. POST THE FRONT THOUGH...MIXING IS DEEPER AND ALTHOUGH THE LOW LEVEL WIND FIELD WON/T BE AS STRONG...THE POTENTIAL FOR HIGHER WIND GUSTS EXISTS. DON/T BELIEVE A WIND ADVISORY WILL BE NEEDED AT THIS TIME...BUT IT COULD BE CLOSE ACROSS THE OPEN AND UNSHELTERED AREAS OF SOUTHEAST MN/NORTHEAST IA TUE AFTERNOON/EVENING. HIGH PRESSURE WILL WORK ACROSS THE REGION WED NIGHT...BRINGING MOSTLY CLEAR SKIES AND LIGHTER WINDS. IN ADDITION...COLDER...BUT SEASONABLE AIR WILL RETURN...WITH RADIATIONAL COOLING HELP TEMPERATURES FALL OFF INTO THE MID TO LOWER 30S BY DAYBREAK THU. PATCHY TO AREAS OF FROST LOOK LIKELY. CONSIDERING THE RECENT VERY WARM TEMPS AND EARLY START TO THE GROWING SEASON...COLD DAMAGE COULD OCCUR TO TENDER VEGETATION AND COLD SENSITIVE PLANTS. A FROST ADVISORY MAY BE NEEDED FOR WEDNESDAY NIGHT. .LONG TERM...FRIDAY THROUGH MONDAY 230 PM CDT MON MAR 26 2012 GFS AND ECMWF IN PRETTY GOOD AGREEMENT WITH RETURN FLOW POST A HIGH INTERACTING WITH A SHORTWAVE TROUGH A LOFT TO TRIGGER AREAS OF SHOWERS AND ISOLATED THUNDERSTORMS THU NIGHT-FRI. BOTH MODELS THEN FAVOR ANOTHER SHORTWAVE TROUGH SLIDING ACROSS THE UPPER MISSISSIPPI RIVER VALLEY FRI NIGHT...POSSIBLY INTO SAT. SOME DIFFERENCES WITH TIMING...POSITIONING AND STRENGTH...BUT THERE DOES LOOK TO BE SOME PCPN CHANCES IN THIS TIME FRAME. A STRONGER TROUGH AND SFC COLD FRONT COULD THEN IMPACT THE AREA SUNDAY INTO MONDAY. AGAIN...DIFFERENCES IN THE MODELS...ALTHOUGH THE SENSIBLE WEATHER IS SIMILAR. SUNDAY NIGHT APPEARS TO BE THE MOST FAVORABLE TIME FOR CONVECTION ALONG THE FRONT TO MOVE IN. && .AVIATION...THROUGH 18Z TUESDAY 1255 PM CDT MON MAR 26 2012 ISOLATED SHOWERS AND BREEZY EAST/SOUTHEAST WINDS WILL PERSIST AT THE TAF SITES THROUGH EARLY THIS EVENING. PLAN ON VFR CONDITIONS WITH CEILINGS IN THE 4 TO 5 KFT RANGE. LOOK FOR WIND SPEEDS OF 15 TO 20 KTS...GUSTING TO AROUND 21 KTS AT KLSE AND UP TO 30 KTS AT KRST. LOW LEVEL WIND SHEAR WILL BE A POTENTIAL CONCERN THIS EVENING THROUGH THE OVERNIGHT HOURS. WINDS WILL INCREASE FROM THE SURFACE AND VEER SOUTHWEST..INCREASING TO 60 KTS AT 2 KFT. HAVE NOT INCLUDED LLWS IN THE TAF GIVEN THE EXPECTED SURFACE WINDS SPEEDS...BUT IT MAY NEED TO BE ADDED THIS EVENING IF SURFACE WINDS DROP OFF. THE LOW LEVEL JET WILL BRING AN OUTSIDE CHANCE OF A SHOWER OR ISOLATED THUNDERSTORM THROUGH THE OVERNIGHT HOURS. CEILINGS ARE EXPECTED TO LOWER INTO THE MVFR RANGE TUESDAY MORNING AS MOIST LOW LEVEL AIR CONTINUES TO BE PUMPED INTO THE REGION AHEAD OF AN APPROACHING COLD FRONT. SOUTHWEST WINDS WILL INCREASE LATE TUESDAY MORNING AHEAD OF THE FRONT. PLAN ON SOUTHWEST WINDS OF 15 TO 20 KTS...WITH GUSTS AROUND 34 KTS POSSIBLE. THE FRONT WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA TUESDAY AFTERNOON. SOME OF THE STORMS COULD PRODUCE STRONG AND GUSTY WINDS...ESPECIALLY IN THE 18Z-22Z TIMEFRAME. PLAN ON STRONG WEST WINDS OF 17 TO 26 KTS...WITH GUSTS AROUND 38 KTS LATE TUESDAY AFTERNOON INTO TUESDAY EVENING. && .ARX WATCHES/WARNINGS/ADVISORIES... 230 PM CDT MON MAR 26 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION.....WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1256 PM CDT MON MAR 26 2012 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT 325 AM CDT MON MAR 26 2012 THE MAIN FOCUS GOING THROUGH MID WEEK IS WITH THE PRECIPITATION CHANCES TODAY INTO TOMORROW AND WHETHER ANY SEVERE THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON. CURRENTLY...A BAND OF SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS HAS DEVELOPED ACROSS SOUTHERN MINNESOTA INTO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AS A RESULT OF THE COMBINATION OF A FRONTOGENETIC CIRCULATION BETWEEN 850-500MB AND THE EASTERN WING OF INCREASING 925-850MB MOISTURE TRANSPORT. THIS CONVECTION IS REACHING THE GROUND DESPITE A DRY LOW LEVEL AIR MASS THAT FEATURES A DEW POINT DEPRESSION OF ABOUT 35C AT 830MB PER THE 26.00Z MPX SOUNDING. THE QUESTION FOR THIS MORNING IS WITH HOW LONG THE CONVECTION WILL HOLD ON FOR. THE 26.00Z NAM CROSS SECTIONS SHOW THIS FRONTOGENETIC CIRCULATION DRIFTING NORTH AND STAYING STRONG THROUGHOUT THE MORNING AND EARLY AFTERNOON BEFORE WEAKENING THIS AFTERNOON. WITH 26.05Z AND PREVIOUS HRRR RUNS SHOWING THIS PRECIPITATION HOLDING ON INTO THE MORNING...HAVE KEPT SOME DECENT CHANCES FOR SHOWERS/ISOLATED THUNDER GOING INTO THE AFTERNOON. ALSO...SKIES REMAINED MOSTLY CLEAR OVERNIGHT ACROSS NORTHERN WISCONSIN AND ALLOWED FOR TEMPERATURES TO DROP BELOW FREEZING AT MEDFORD. THEREFORE...WILL KEEP THE FREEZE WARNING GOING UNTIL 8AM FOR TAYLOR COUNTY. JUST AS THIS FIRST BAND OF FORCING WEAKENS THIS AFTERNOON...925-850MB MOISTURE TRANSPORT AND ISENTROPIC LIFT ON THE 300-310K SURFACES WILL BE ON THE INCREASE ACROSS SOUTHERN MINNESOTA AND NORTH CENTRAL IOWA. THIS WILL LEAD TO A BAND OF CONVECTION REDEVELOPING ACROSS THIS AREA WHILE LIFTING TO THE NORTHEAST THROUGH THE LATE AFTERNOON AND EVENING HOURS. WITH THIS 925-850MB MOISTURE TRANSPORT NOSE SHIFTING NORTHEAST AND STRENGTHENING THROUGH THE EVENING AND OVERNIGHT HOURS...CHANCES STILL LOOK FAIRLY GOOD FOR THIS CONVECTION HOLDING ON THROUGH THE NIGHT...PARTICULARLY ACROSS SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. A FEW HUNDRED J/KG OF MID LEVEL INSTABILITY FEEDING INTO THESE SHOWERS SHOULD LEAD TO SOME THUNDER OCCURRING...BUT NOTHING VIGOROUS ENOUGH TO GET ORGANIZED AND POSE A SEVERE THREAT. AS THIS FEATURE LIFTS OFF TO THE NORTH...THE MAIN CHANNEL OF LOW LEVEL MOISTURE TRANSPORT WILL MOVE ACROSS THE REGION TUESDAY MORNING AHEAD OF THE COLD FRONT OR POSSIBLY A PRE-FRONTAL TROUGH. AS THIS MOISTURE FEED SHIFTS EAST TUESDAY AFTERNOON...THE MAIN COLD FRONT WILL TRACK EAST AS WELL AND GET TO THE MISSISSIPPI RIVER BY MID AFTERNOON. THE 26.00Z NAM CONTINUES TO SHOW SOME 0-3KM MUCAPE OF 500-1500 J/KG DEVELOPING AHEAD OF THIS FRONT IN THE AFTERNOON...BUT DOES NOT SHOW MUCH IN THE WAY OF QPF ACROSS SOUTHWEST WISCONSIN. IT DOES CONVECT FURTHER SOUTH IN EASTERN IOWA WHERE THIS INSTABILITY CROSSES THE LOW LEVEL MOISTURE TRANSPORT. DESPITE 0-3KM WIND SHEAR BEING VERY FAVORABLE AT 40KTS...THE PROSPECTS FOR ORGANIZED CONVECTION STILL APPEAR TO BE FAIRLY LOW ACROSS SOUTHWEST WISCONSIN. IF THE COLD FRONT CAN PROVIDE ENOUGH OF A KICKER...A FEW STORMS MAY BE ABLE TO FORM THOUGH THE WINDOW LOOKS VERY SMALL IN THE LATE AFTERNOON. AFTER THE FRONT MOVES THROUGH...A COOLER AND VERY DRY AIR MASS ADVECTS INTO THE REGION WITH 850MB TEMPERATURES DROPPING FROM +10C TUESDAY AFTERNOON TO AROUND -2C BY WEDNESDAY MORNING. WITH THIS COLDER...YET SEASONAL...AIR MASS IN PLACE...LOW TEMPERATURES WEDNESDAY NIGHT WILL BE CLOSE TO FREEZING IN WESTERN WISCONSIN. HAVE NOT PUT ANY FROST IN THE FORECAST YET SINCE WINDS APPEAR TO STAY STRONG ENOUGH TO KEEP ANY FROM FORMING. .LONG TERM...THURSDAY THROUGH SUNDAY NIGHT 325 AM CDT MON MAR 26 2012 EXTENDED GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH FRIDAY BEFORE THE 26.00Z GFS AND ECMWF GET OUT OF PHASE WITH EACH OTHER. A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH THE REGION ON THURSDAY BEFORE A MID LEVEL SHORTWAVE TROUGH SWINGS ACROSS THE NORTHERN PLAINS THURSDAY NIGHT. THIS WILL BRING SOUTHERLY RETURN FLOW UP INTO THE UPPER MISSISSIPPI RIVER VALLEY AHEAD OF THIS TROUGH AND BRING THE NEXT ROUND OF SHOWERS/STORMS ON IN. SOME DISCREPANCIES START SHOWING UP ON FRIDAY AS THE 26.00Z GFS HOLDS ONTO THE PRECIPITATION LONGER THAN THE 26.00Z ECMWF. THE 26.00Z ECMWF/GEM BOTH BRING A MORE POTENT LOW THROUGH ON FRIDAY/SATURDAY THAN WHAT THE 26.00Z GFS HAS. BEYOND THIS...THE GFS HOLDS UP THE TROUGH OUT WEST WHILE THE ECMWF IS MUCH MORE PROGRESSIVE. FOR NOW...HAVE CONTINUED THE TREND OF GOING WITH A CONSENSUS BLEND OF EACH RATHER THAN TO GRAB ONTO ONE EXTREME OR THE OTHER WITH THE GFS BEING THE WARM EXTREME AND THE ECMWF BEING THE COLD EXTREME. && .AVIATION...THROUGH 18Z TUESDAY 1255 PM CDT MON MAR 26 2012 ISOLATED SHOWERS AND BREEZY EAST/SOUTHEAST WINDS WILL PERSIST AT THE TAF SITES THROUGH EARLY THIS EVENING. PLAN ON VFR CONDITIONS WITH CEILINGS IN THE 4 TO 5 KFT RANGE. LOOK FOR WIND SPEEDS OF 15 TO 20 KTS...GUSTING TO AROUND 21 KTS AT KLSE AND UP TO 30 KTS AT KRST. LOW LEVEL WIND SHEAR WILL BE A POTENTIAL CONCERN THIS EVENING THROUGH THE OVERNIGHT HOURS. WINDS WILL INCREASE FROM THE SURFACE AND VEER SOUTHWEST..INCREASING TO 60 KTS AT 2 KFT. HAVE NOT INCLUDED LLWS IN THE TAF GIVEN THE EXPECTED SURFACE WINDS SPEEDS...BUT IT MAY NEED TO BE ADDED THIS EVENING IF SURFACE WINDS DROP OFF. THE LOW LEVEL JET WILL BRING AN OUTSIDE CHANCE OF A SHOWER OR ISOLATED THUNDERSTORM THROUGH THE OVERNIGHT HOURS. CEILINGS ARE EXPECTED TO LOWER INTO THE MVFR RANGE TUESDAY MORNING AS MOIST LOW LEVEL AIR CONTINUES TO BE PUMPED INTO THE REGION AHEAD OF AN APPROACHING COLD FRONT. SOUTHWEST WINDS WILL INCREASE LATE TUESDAY MORNING AHEAD OF THE FRONT. PLAN ON SOUTHWEST WINDS OF 15 TO 20 KTS...WITH GUSTS AROUND 34 KTS POSSIBLE. THE FRONT WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA TUESDAY AFTERNOON. SOME OF THE STORMS COULD PRODUCE STRONG AND GUSTY WINDS...ESPECIALLY IN THE 18Z-22Z TIMEFRAME. PLAN ON STRONG WEST WINDS OF 17 TO 26 KTS...WITH GUSTS AROUND 38 KTS LATE TUESDAY AFTERNOON INTO TUESDAY EVENING. && .ARX WATCHES/WARNINGS/ADVISORIES... 1255 PM CDT MON MAR 26 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM....HALBACH AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1224 PM CDT MON MAR 26 2012 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY AND TUESDAY. ACTIVE PERIOD EXPECTED...WITH CONCERNS ON PCPN AND TYPE AND TEMPERATURES. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE OUT OF CANADA NOSING SOUTH INTO WI. FEW PATCHES OF LOW CLOUDS CONTINUE TO FLOAT IN OFF LAKES. TO SOUTHWEST MID CLOUDS COVER THE AREA...WITH FEW LIGHT SHOWERS MOVING THROUGH SOUTHERN WI ASSOCIATED WITH AN AREA OF FGEN FORCING. FREEZE WARNING WILL REMAIN AS IS. FORECAST ATTENTION ON SIG SHORT WAVE LIFTING NORTHEAST OUT OF WESTERN TROF INTO THE DAKOTAS BY TUE MORNING. AT THE SURFACE...HIGH AND ASSOCIATED COLD AIR MASS TO MOVE EAST TODAY WITH COLD FRONT RETURNING NORTH AS A WARM FRONT TONIGHT. AREA OF STEEP MID LEVEL LAPSE RATES/LI`S NEAR 0 SHIFTS EAST INTO REGION TONIGHT...WITH ELEVATED THUNDER POSSIBLE OVERNIGHT. LOW LEVEL FLOW INCREASES TO 40KTS...FOCUSED OVER NORTH THUS HIGHER POPS OVER NORTHERN CWA. SOUNDINGS INDICATE DRY LAYER BELOW 800MB HAS TO BE OVERCOME THIS EVENING...TRENDED POPS LOWER EAST BEFORE MIDNIGHT. PCPN TYPE ALSO IN QUESTION. DEPTH OF THE BELOW FREEZING LAYER ON SOUNDINGS DEEP ENOUGH TO REFREEZE...WHILE CONVECTION ALSO SUGGESTS SLEET. THOUGH CAN NOT TOTALLY RULE OUT FZRA. TEMPERATURES EXPECTED TO BE JUST BELOW FREEZING FOR LOWS...THEN WARM TOWARD MORNING... LIMITING ZR. WILL NOT PUT ZR IN GRIDS ATTM AND PASS CONCERNS REGARDING IT ON TO NEXT SHIFT. COLD FRONT TO MOVE INTO CWA LATE IN DAY TUE. MODELS SUGGEST POSSIBLE CONVECTION OUT AHEAD OF FRONT. INSTABILITY LIMITED WITH DEW POINTS ONLY RISING INTO THE LOWER 50S. INSTABILITY MAINLY FOCUSED TO OUR SOUTH AND WEST. STRONG SOUTH TO SOUTHEAST FLOW WILL ALSO BE A STABILIZING FACTOR AND LIMIT TEMPERATURES IN THE EAST. HAVE BACKED POPS BACK DOWN INTO SCATTERED RANGE FOR TUE. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY. LOW PRESSURE ACROSS SOUTHWEST ONTARIO WILL MOVE EAST SOUTHEAST TO NORTH OF LAKE HURON BY 12Z WEDNESDAY MORNING. COLD FRONT WILL MOVE RAPIDLY EAST OF THE STATE TUESDAY NIGHT. BEEN CONTEMPLATING IF A SMALL CHANCE WOULD BE NEEDED ACROSS THE EAST. DO THINK IF ANY ACTIVITY DOES FORM TUESDAY AFTERNOON...IT WILL RACE RAPIDLY TO THE NORTHEAST AND BE OUT OF OUR FORECAST AREA BY 00Z. SOME CONCERNS TONIGHT THAT THE MODELS ARE UNDER DOING THE WINDS TUESDAY NIGHT. VERY STRONG WINDS AT 925MB...COMBINED WITH SOME SUBSIDENCE BEHIND THE COLD FRONT AND 850MB COLD ADVECTION SHOULD HELP MIX SOME OF THE STRONGER WINDS ALOFT DOWN TO THE SURFACE. HAVE GONE WITH BLUSTERY WORDING FOR NOW IN THE ZONES. WOULD NOT BE SURPRISED IF A FEW GUSTS TO OVER 30 KNOTS ARE POSSIBLE TUESDAY EVENING. WINDS SHOULD GRADUALLY DIMINISH OVERNIGHT. ON WEDNESDAY...CONTINUED CHANCES FOR RAIN OR SNOW OVER FAR NORTH CENTRAL WISCONSIN. ON THE 00Z MODEL RUNS TONIGHT...BOTH THE GFS/WRF INDICATING 500MB TROUGH MOVING ACROSS NORTHEAST WISCONSIN WHILE THE BOTH MODELS DO SHOW SOME SURFACE CONVERGENCE ALONG A WEAK TROUGH/COLD FRONT. DID EXPAND PRECIPITATION CHANCES FURTHER SOUTH AND NOW INCLUDES MOST OF THE FORECAST AREA EXCEPT THE VERY FAR SOUTHWEST. HIGH PRESSURE WILL BUILD INTO NORTH CENTRAL AND NORTHEAST WISCONSIN WEDNESDAY NIGHT. WITH RIDGE AXIS OVERHEAD BY 12Z THURSDAY...A WIDESPREAD FREEZE IS LIKELY ACROSS THE NORTH AWAY FROM THE BAY WITH AREAS OF FROST OVER THE REMAINDER OF THE FORECAST AREA. WITH THE RECENT RECORD WARMTH...THE GROWING SEASON HAS STARTED VERY EARLY ACROSS WISCONSIN. HAVE ADDED FROST TO THE FORECAST TO INDICATE THE POTENTIAL FOR MORE TEMPERATURES AT OR BELOW FREEZING. NEXT SYSTEM WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA THURSDAY NIGHT INTO FRIDAY. NEXT WEEKEND STILL LOOKS MUDDLED BETWEEN THE MODELS...THEREFORE NO CHANGES TO THE FORECAST. && .AVIATION...CANADIAN HIGH PRESSURE WILL RETREAT TO THE NORTHEAST WHILE A WARM FRONT OVER THE NORTHERN PLAINS WILL MOVE NORTHEAST ACROSS THE REGION TONIGHT INTO TUESDAY MORNING. LIGHT SHOWER ACTIVITY OVER WESTERN WISCONSIN WILL SHIFT ACROSS CENTRAL AND NORTHERN WISCONSIN ALONG THE FRONT TONIGHT. WILL SEE INCREASING CLOUDS THIS AFTERNOON AND EARLY THIS EVENING BEFORE PRECIP ARRIVES. PRECIP TYPE IS UNCERTAIN...MAINLY DUE TO THE NEAR SURFACE TEMPERATURES AS COOLING TAKES PLACE TONIGHT. FORECAST MODELS PROJECT TEMPS FALLING TO JUST BELOW FREEZING...THOUGH INCOMING CLOUD COVER MAY KEEP TEMPS SLIGHTLY HIGHER THAN THE MODELS PREDICT. AS A RESULT...THINK FREEZING RAIN AND SLEET IS POSSIBLE OVER NORTHERN WISCONSIN TONIGHT...THOUGH IMPACTS MAY TURN OUT TO BE MINIMAL DUE TO SURFACE TEMPS SO CLOSE TO FREEZING. THE PRECIP WILL PULL OUT LATE TONIGHT...WHICH WILL LEAVE MVFR CIGS OVER CENTRAL AND NORTH-CENTRAL WISCONSIN FOR MUCH OF TUESDAY MORNING. MPC && .MARINE...SMALL CRAFT WILL BE ALLOWED TO RUN THROUGH 15Z. WINDS HAVE DROPPED BELOW CRITERIA...THOUGH WAVES WILL BE SLOWER TO DROP OFF. INCREASING SOUTHEAST...SOUTH WINDS EXPECTED TONIGHT AS LLVL FLOW INCREASES TO 40KTS AT 925MB. UNDER WAA REGIME HAVE CONCERNS THAT A STRONG INVERSION WILL LIMIT MIXING OF HIGHER WINDS DOWN...WITH GFS SOUNDINGS SUGGESTING SAME. WILL STAY WITH STRONG SMALL CRAFT WORDING AT THIS TIME. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
645 AM CDT MON MAR 26 2012 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT 325 AM CDT MON MAR 26 2012 THE MAIN FOCUS GOING THROUGH MID WEEK IS WITH THE PRECIPITATION CHANCES TODAY INTO TOMORROW AND WHETHER ANY SEVERE THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON. CURRENTLY...A BAND OF SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS HAS DEVELOPED ACROSS SOUTHERN MINNESOTA INTO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AS A RESULT OF THE COMBINATION OF A FRONTOGENETIC CIRCULATION BETWEEN 850-500MB AND THE EASTERN WING OF INCREASING 925-850MB MOISTURE TRANSPORT. THIS CONVECTION IS REACHING THE GROUND DESPITE A DRY LOW LEVEL AIR MASS THAT FEATURES A DEW POINT DEPRESSION OF ABOUT 35C AT 830MB PER THE 26.00Z MPX SOUNDING. THE QUESTION FOR THIS MORNING IS WITH HOW LONG THE CONVECTION WILL HOLD ON FOR. THE 26.00Z NAM CROSS SECTIONS SHOW THIS FRONTOGENETIC CIRCULATION DRIFTING NORTH AND STAYING STRONG THROUGHOUT THE MORNING AND EARLY AFTERNOON BEFORE WEAKENING THIS AFTERNOON. WITH 26.05Z AND PREVIOUS HRRR RUNS SHOWING THIS PRECIPITATION HOLDING ON INTO THE MORNING...HAVE KEPT SOME DECENT CHANCES FOR SHOWERS/ISOLATED THUNDER GOING INTO THE AFTERNOON. ALSO...SKIES REMAINED MOSTLY CLEAR OVERNIGHT ACROSS NORTHERN WISCONSIN AND ALLOWED FOR TEMPERATURES TO DROP BELOW FREEZING AT MEDFORD. THEREFORE...WILL KEEP THE FREEZE WARNING GOING UNTIL 8AM FOR TAYLOR COUNTY. JUST AS THIS FIRST BAND OF FORCING WEAKENS THIS AFTERNOON...925-850MB MOISTURE TRANSPORT AND ISENTROPIC LIFT ON THE 300-310K SURFACES WILL BE ON THE INCREASE ACROSS SOUTHERN MINNESOTA AND NORTH CENTRAL IOWA. THIS WILL LEAD TO A BAND OF CONVECTION REDEVELOPING ACROSS THIS AREA WHILE LIFTING TO THE NORTHEAST THROUGH THE LATE AFTERNOON AND EVENING HOURS. WITH THIS 925-850MB MOISTURE TRANSPORT NOSE SHIFTING NORTHEAST AND STRENGTHENING THROUGH THE EVENING AND OVERNIGHT HOURS...CHANCES STILL LOOK FAIRLY GOOD FOR THIS CONVECTION HOLDING ON THROUGH THE NIGHT...PARTICULARLY ACROSS SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. A FEW HUNDRED J/KG OF MID LEVEL INSTABILITY FEEDING INTO THESE SHOWERS SHOULD LEAD TO SOME THUNDER OCCURRING...BUT NOTHING VIGOROUS ENOUGH TO GET ORGANIZED AND POSE A SEVERE THREAT. AS THIS FEATURE LIFTS OFF TO THE NORTH...THE MAIN CHANNEL OF LOW LEVEL MOISTURE TRANSPORT WILL MOVE ACROSS THE REGION TUESDAY MORNING AHEAD OF THE COLD FRONT OR POSSIBLY A PRE-FRONTAL TROUGH. AS THIS MOISTURE FEED SHIFTS EAST TUESDAY AFTERNOON...THE MAIN COLD FRONT WILL TRACK EAST AS WELL AND GET TO THE MISSISSIPPI RIVER BY MID AFTERNOON. THE 26.00Z NAM CONTINUES TO SHOW SOME 0-3KM MUCAPE OF 500-1500 J/KG DEVELOPING AHEAD OF THIS FRONT IN THE AFTERNOON...BUT DOES NOT SHOW MUCH IN THE WAY OF QPF ACROSS SOUTHWEST WISCONSIN. IT DOES CONVECT FURTHER SOUTH IN EASTERN IOWA WHERE THIS INSTABILITY CROSSES THE LOW LEVEL MOISTURE TRANSPORT. DESPITE 0-3KM WIND SHEAR BEING VERY FAVORABLE AT 40KTS...THE PROSPECTS FOR ORGANIZED CONVECTION STILL APPEAR TO BE FAIRLY LOW ACROSS SOUTHWEST WISCONSIN. IF THE COLD FRONT CAN PROVIDE ENOUGH OF A KICKER...A FEW STORMS MAY BE ABLE TO FORM THOUGH THE WINDOW LOOKS VERY SMALL IN THE LATE AFTERNOON. AFTER THE FRONT MOVES THROUGH...A COOLER AND VERY DRY AIR MASS ADVECTS INTO THE REGION WITH 850MB TEMPERATURES DROPPING FROM +10C TUESDAY AFTERNOON TO AROUND -2C BY WEDNESDAY MORNING. WITH THIS COLDER...YET SEASONAL...AIR MASS IN PLACE...LOW TEMPERATURES WEDNESDAY NIGHT WILL BE CLOSE TO FREEZING IN WESTERN WISCONSIN. HAVE NOT PUT ANY FROST IN THE FORECAST YET SINCE WINDS APPEAR TO STAY STRONG ENOUGH TO KEEP ANY FROM FORMING. .LONG TERM...THURSDAY THROUGH SUNDAY NIGHT 325 AM CDT MON MAR 26 2012 EXTENDED GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH FRIDAY BEFORE THE 26.00Z GFS AND ECMWF GET OUT OF PHASE WITH EACH OTHER. A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH THE REGION ON THURSDAY BEFORE A MID LEVEL SHORTWAVE TROUGH SWINGS ACROSS THE NORTHERN PLAINS THURSDAY NIGHT. THIS WILL BRING SOUTHERLY RETURN FLOW UP INTO THE UPPER MISSISSIPPI RIVER VALLEY AHEAD OF THIS TROUGH AND BRING THE NEXT ROUND OF SHOWERS/STORMS ON IN. SOME DISCREPANCIES START SHOWING UP ON FRIDAY AS THE 26.00Z GFS HOLDS ONTO THE PRECIPITATION LONGER THAN THE 26.00Z ECMWF. THE 26.00Z ECMWF/GEM BOTH BRING A MORE POTENT LOW THROUGH ON FRIDAY/SATURDAY THAN WHAT THE 26.00Z GFS HAS. BEYOND THIS...THE GFS HOLDS UP THE TROUGH OUT WEST WHILE THE ECMWF IS MUCH MORE PROGRESSIVE. FOR NOW...HAVE CONTINUED THE TREND OF GOING WITH A CONSENSUS BLEND OF EACH RATHER THAN TO GRAB ONTO ONE EXTREME OR THE OTHER WITH THE GFS BEING THE WARM EXTREME AND THE ECMWF BEING THE COLD EXTREME. && .AVIATION...TODAY INTO TUESDAY 645 AM CDT MON MAR 26 2012 MOISTURE TRANSPORT/LIFT IN THE 850-700MB LAYER WILL CONTINUE TO PRODUCE SCT -SHRA AND ISOLATED -TSRA ACROSS THE AREA THIS MORNING. WITH THE FORCING ELEVATED AND A DRIER LOWER LEVEL EASTERLY FLOW OVER THE AREA...CIGS/VSBYS LOOKING TO REMAIN VFR WITH MOST IF NOT ALL OF THE -SHRA. WITH ANY -TSRA ISOLATED...ONLY INCLUDED A CB MENTION FOR THE LATER MORNING HOURS. MOISTURE TRANSPORT/LIFT WEAKENS FOR THE AFTERNOON WITH A LULL IN THE -SHRA...THEN INCREASES AGAIN FOR TONIGHT. WITH THE PERSISTENT AND INCREASING EAST/SOUTHEAST SFC-850MB FLOW...CIGS/VSBYS WITH ANY -SHRA/ISOLATED -TSRA TONIGHT AGAIN LOOK TO REMAIN VFR. WITH SCT COVERAGE AND THE -SHRA LOOKING TO BE LIGHT ONLY INCLUDED VCSH IN TAFS FOR TONIGHT. TIGHT PRESSURE GRADIENT OVER THE AREA TODAY/TONIGHT WILL RESULT IN BRISK EAST/ SOUTHEAST WINDS THRU THE PERIOD...ESPECIALLY AT THE HIGHER/OPEN TERRAIN SITES LIKE KRST. A COLD FRONT WILL SWEEP ACROSS THE AREA TUE...SWINGING THE WINDS TO THE SOUTHWEST. SUBSIDENCE AND TIGHT GRADIENT BEHIND THE FRONT WILL RESULT IN SOUTHWEST WINDS 20-25KT G35KT MUCH OF TUE... AGAIN MAINLY AT THE HIGHER/OPEN TERRAIN SITES LIKE KRST. && .ARX WATCHES/WARNINGS/ADVISORIES... 325 AM CDT MON MAR 26 2012 WI...FREEZE WARNING UNTIL 8 AM CDT MONDAY FOR WIZ017. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM....HALBACH AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
457 AM CDT MON MAR 26 2012 .SHORT TERM...TODAY AND TUESDAY. ACTIVE PERIOD EXPECTED...WITH CONCERNS ON PCPN AND TYPE AND TEMPERATURES. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE OUT OF CANADA NOSING SOUTH INTO WI. FEW PATCHES OF LOW CLOUDS CONTINUE TO FLOAT IN OFF LAKES. TO SOUTHWEST MID CLOUDS COVER THE AREA...WITH FEW LIGHT SHOWERS MOVING THROUGH SOUTHERN WI ASSOCIATED WITH AN AREA OF FGEN FORCING. FREEZE WARNING WILL REMAIN AS IS. FORECAST ATTENTION ON SIG SHORT WAVE LIFTING NORTHEAST OUT OF WESTERN TROF INTO THE DAKOTAS BY TUE MORNING. AT THE SURFACE...HIGH AND ASSOCIATED COLD AIR MASS TO MOVE EAST TODAY WITH COLD FRONT RETURNING NORTH AS A WARM FRONT TONIGHT. AREA OF STEEP MID LEVEL LAPSE RATES/LI`S NEAR 0 SHIFTS EAST INTO REGION TONIGHT...WITH ELEVATED THUNDER POSSIBLE OVERNIGHT. LOW LEVEL FLOW INCREASES TO 40KTS...FOCUSED OVER NORTH THUS HIGHER POPS OVER NORTHERN CWA. SOUNDINGS INDICATE DRY LAYER BELOW 800MB HAS TO BE OVERCOME THIS EVENING...TRENDED POPS LOWER EAST BEFORE MIDNIGHT. PCPN TYPE ALSO IN QUESTION. DEPTH OF THE BELOW FREEZING LAYER ON SOUNDINGS DEEP ENOUGH TO REFREEZE...WHILE CONVECTION ALSO SUGGESTS SLEET. THOUGH CAN NOT TOTALLY RULE OUT FZRA. TEMPERATURES EXPECTED TO BE JUST BELOW FREEZING FOR LOWS...THEN WARM TOWARD MORNING... LIMITING ZR. WILL NOT PUT ZR IN GRIDS ATTM AND PASS CONCERNS REGARDING IT ON TO NEXT SHIFT. COLD FRONT TO MOVE INTO CWA LATE IN DAY TUE. MODELS SUGGEST POSSIBLE CONVECTION OUT AHEAD OF FRONT. INSTABILITY LIMITED WITH DEW POINTS ONLY RISING INTO THE LOWER 50S. INSTABILITY MAINLY FOCUSED TO OUR SOUTH AND WEST. STRONG SOUTH TO SOUTHEAST FLOW WILL ALSO BE A STABILIZING FACTOR AND LIMIT TEMPERATURES IN THE EAST. HAVE BACKED POPS BACK DOWN INTO SCATTERED RANGE FOR TUE. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY. LOW PRESSURE ACROSS SOUTHWEST ONTARIO WILL MOVE EAST SOUTHEAST TO NORTH OF LAKE HURON BY 12Z WEDNESDAY MORNING. COLD FRONT WILL MOVE RAPIDLY EAST OF THE STATE TUESDAY NIGHT. BEEN CONTEMPLATING IF A SMALL CHANCE WOULD BE NEEDED ACROSS THE EAST. DO THINK IF ANY ACTIVITY DOES FORM TUESDAY AFTERNOON...IT WILL RACE RAPIDLY TO THE NORTHEAST AND BE OUT OF OUR FORECAST AREA BY 00Z. SOME CONCERNS TONIGHT THAT THE MODELS ARE UNDER DOING THE WINDS TUESDAY NIGHT. VERY STRONG WINDS AT 925MB...COMBINED WITH SOME SUBSIDENCE BEHIND THE COLD FRONT AND 850MB COLD ADVECTION SHOULD HELP MIX SOME OF THE STRONGER WINDS ALOFT DOWN TO THE SURFACE. HAVE GONE WITH BLUSTERY WORDING FOR NOW IN THE ZONES. WOULD NOT BE SURPRISED IF A FEW GUSTS TO OVER 30 KNOTS ARE POSSIBLE TUESDAY EVENING. WINDS SHOULD GRADUALLY DIMINISH OVERNIGHT. ON WEDNESDAY...CONTINUED CHANCES FOR RAIN OR SNOW OVER FAR NORTH CENTRAL WISCONSIN. ON THE 00Z MODEL RUNS TONIGHT...BOTH THE GFS/WRF INDICATING 500MB TROUGH MOVING ACROSS NORTHEAST WISCONSIN WHILE THE BOTH MODELS DO SHOW SOME SURFACE CONVERGENCE ALONG A WEAK TROUGH/COLD FRONT. DID EXPAND PRECIPITATION CHANCES FURTHER SOUTH AND NOW INCLUDES MOST OF THE FORECAST AREA EXCEPT THE VERY FAR SOUTHWEST. HIGH PRESSURE WILL BUILD INTO NORTH CENTRAL AND NORTHEAST WISCONSIN WEDNESDAY NIGHT. WITH RIDGE AXIS OVERHEAD BY 12Z THURSDAY...A WIDESPREAD FREEZE IS LIKELY ACROSS THE NORTH AWAY FROM THE BAY WITH AREAS OF FROST OVER THE REMAINDER OF THE FORECAST AREA. WITH THE RECENT RECORD WARMTH...THE GROWING SEASON HAS STARTED VERY EARLY ACROSS WISCONSIN. HAVE ADDED FROST TO THE FORECAST TO INDICATE THE POTENTIAL FOR MORE TEMPERATURES AT OR BELOW FREEZING. NEXT SYSTEM WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA THURSDAY NIGHT INTO FRIDAY. NEXT WEEKEND STILL LOOKS MUDDLED BETWEEN THE MODELS...THEREFORE NO CHANGES TO THE FORECAST. && .AVIATION...THE MAIN AREA OF MVFR CIGS THAT WAS OVER THE UPPER PENINSULA EARLIER IN THE EVENING DISSIPATED AS IT MOVED INTO NE WI...BUT PATCHY LOW CLOUDS CONTINUED TO DEVELOP OVER THE LAKE/BAY AND MOVE INTO NE/EC WI. HAVE BACKED OFF ON PREVAILING MVFR CIGS AT ANY OF THE TAF SITES...BUT KEPT TEMPO GROUPS FOR BKN015-020 AT ATW/GRB THROUGH 12Z/MON. MID-LEVEL CLOUDS CONTINUED TO STREAM INTO CENTRAL WI LATE THIS EVENING...BUT SHOWERS OVER SE MN SHOULD STAY TO OUR SOUTHWEST THROUGH MONDAY. SCT SHOWERS WILL PUSH INTO THE REGION ON MONDAY EVG AS THE NEXT SYSTEM APPROACHES. IN ADDITION...SOME LLWS IS EXPECTED TO DEVELOP AT RHI/AUW/CWA LATE MONDAY EVENING. KIECKBUSCH && .MARINE...SMALL CRAFT WILL BE ALLOWED TO RUN THROUGH 15Z. WINDS HAVE DROPPED BELOW CRITERIA...THOUGH WAVES WILL BE SLOWER TO DROP OFF. INCREASING SOUTHEAST...SOUTH WINDS EXPECTED TONIGHT AS LLVL FLOW INCREASES TO 40KTS AT 925MB. UNDER WAA REGIME HAVE CONCERNS THAT A STRONG INVERSION WILL LIMIT MIXING OF HIGHER WINDS DOWN...WITH GFS SOUNDINGS SUGGESTING SAME. WILL STAY WITH STRONG SMALL CRAFT WORDING AT THIS TIME. && .GRB WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR WIZ005-010>013- 018-019-021. && $$ TE/ECKBERG
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1149 PM CDT SUN MAR 25 2012 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE COLD FRONT DROPPING INTO NORTHERN ILLINOIS EARLY THIS AFTERNOON WHILE CANADIAN HIGH PRESSURE IS BUILDING SOUTH INTO THE NORTHERN MISSISSIPPI VALLEY. LOW STRATO-CU DISSIPATED RATHER QUICKLY EARLIER TODAY AS MIXING INTO DRIER AIR OVERWHELMED THE SHALLOW COOL AND MOIST AIRMASS. STILL SOME LINGERING CU OVER EAST-CENTRAL WISCONSIN...THOUGH TRENDS SUPPORT IT DISSIPATING AS WELL OVER THE NEXT COUPLE HOURS. UPSTREAM IS PRETTY QUIET...WITH ONLY MID AND HIGH CLOUDS PUSHING ACROSS THE DAKOTAS. AS HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION TONIGHT...LOW TEMPS AND HEADLINES ARE THE MAIN FORECAST CONCERNS. TONIGHT...LAST NIGHTS COLD FRONT WILL CONTINUE TO SAG SOUTH TOWARDS THE OHIO VALLEY WHILE CANADIAN HIGH PRESSURE WILL BUILD INTO SOUTHERN ONTARIO AND THE WESTERN GREAT LAKES. THIS INCOMING AIRMASS FROM CANADA IS QUITE DRY AND WILL DROP PWATS TO UNDER A QUARTER OF AN INCH. THOUGH AIRMASS IS VERY DRY...NOT IDEAL RADIATIONAL COOLING CONDITIONS WILL BE IN PLACE FOR TONIGHT. WILL HAVE SCT-BKN MID AND HIGH CLOUDS ARRIVE FROM THE NORTHERN PLAINS INTO MUCH OF CENTRAL AND EAST-CENTRAL WISCONSIN BY LATE THIS EVENING. THE PRESSURE GRADIENT WILL ALSO REMAIN FAIRLY TIGHT OVER NE WISCONSIN WHERE NE WINDS FUNNELED DOWN THE BAY...AND ALSO OFF LAKE MICHIGAN WILL KEEP THE BL RATHER BREEZY. NORTH-CENTRAL WISCONSIN WILL SEE 1000-850MB WINDS AROUND 15 KTS...WHICH IS RIGHT ON THE EDGE FOR DECOUPLING. AM GOING TO LEAN TOWARDS DECOUPLING OCCURRING...DUE TO SANDY SOIL EFFECTS AND CLOUDS SHIFTING SOUTH THROUGH THE NIGHT. AS A RESULT...MID TWENTY LOWS SEEM PERFECTLY REASONABLE UP NORTH...AND SEE LITTLE REASON TO ADJUST HEADLINES. DID RAISE LOWS A DEGREE OR TWO OVER CENTRAL AND EAST-CENTRAL WISCONSIN BECAUSE OF CLOUDS AND WIND. LOWS IN THE LOWER TO MIDDLE 30S HERE. MONDAY...MID-LEVEL CLOUDS WILL STALL OVER SW WISCONSIN TOMORROW MORNING AND WILL RETURN NE IN THE AFTERNOON WHEN THE COLD FRONT STARTS RETURNING NORTH. NE WISCONSIN WILL SEE A MOSTLY SUNNY DAY...BUT CENTRAL AND NORTH-CENTRAL WISCONSIN WILL SEE A GRADUAL INCREASE IN CLOUDS. HIGHS RANGING FROM THE LOWER TO MIDDLE 40S EVERYWHERE. .LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. THE WEATHER WILL BE MORE SEASONABLE THAN THE LAST TWO WEEKS WITH FLATTER ALMOST ZONAL FLOW OVER MUCH OF THE REGION THROUGH FRIDAY. SIGNIFICANT MODEL DIFFERENCES FOR NEXT SATURDAY AND SUNDAY WITH HIGH AMPLITUDE FLOW EXPECTED NEXT WEEK. UPPER TROUGH LIFTING NORTHEAST THROUGH THE NORTHERN PLAINS MONDAY NIGHT WILL BRING SHOWERS AND ELEVATED THUNDERSTORMS MONDAY NIGHT AND EARLY TUESDAY. THERE MIGHT BE ENOUGH COLD AIR FOR SLEET TO BE MIXED IN ACROSS THE NORTHERN PART OF THE FORECAST AREA. A COLD FRONT MOVES THROUGH TUESDAY AFTERNOON OR EVENING ACCOMPANIED BY STRONG WINDS IN THE LOW LEVELS...LOTS OF SHEAR AND DECENT UPPER SUPPORT. MOISTURE SHOULD BE LACKING THOUGH WHICH WILL LIMIT INSTABILITY. THERE IS SOME CHANCE OF SEVERE THUNDERSTORMS IF MOISTURE IS MORE PLENTIFUL THAN CURRENTLY EXPECTED. COOLER WEATHER IS EXPECTED FOR WEDNESDAY NIGHT THROUGH FRIDAY AS CANADIAN HIGH SINKS SOUTH INTO THE GREAT LAKES. WILL LIKELY HAVE SOME SUB FREEZING NIGHTS...WHICH IS COMPLETELY NORMAL FOR THIS TIME OF THE YEAR...BUT MORE OF A CONCERN THIS YEAR DUE TO UNUSUAL WARMTH THAT HAS STARTED AN EARLY GROWING SEASON. BIG DIFFERENCES FOR NEXT SATURDAY AND SUNDAY WITH THE GFS AND ECMWF ALMOST 180 DEGREES OUT OF PHASE OVER OUR AREA. && .AVIATION...THE MAIN AREA OF MVFR CIGS THAT WAS OVER THE UPPER PENINSULA EARLIER IN THE EVENING DISSIPATED AS IT MOVED INTO NE WI...BUT PATCHY LOW CLOUDS CONTINUED TO DEVELOP OVER THE LAKE/BAY AND MOVE INTO NE/EC WI. HAVE BACKED OFF ON PREVAILING MVFR CIGS AT ANY OF THE TAF SITES...BUT KEPT TEMPO GROUPS FOR BKN015-020 AT ATW/GRB THROUGH 12Z/MON. MID-LEVEL CLOUDS CONTINUED TO STREAM INTO CENTRAL WI LATE THIS EVENING...BUT SHOWERS OVER SE MN SHOULD STAY TO OUR SOUTHWEST THROUGH MONDAY. SCT SHOWERS WILL PUSH INTO THE REGION ON MONDAY EVG AS THE NEXT SYSTEM APPROACHES. IN ADDITION...SOME LLWS IS EXPECTED TO DEVELOP AT RHI/AUW/CWA LATE MONDAY EVENING. KIECKBUSCH && .MARINE... A WARM FRONT WILL PUSH NORTHWARD ACROSS THE AREA TUESDAY. GUSTS TO NEAR GALE FORCE FROM THE SOUTHEAST/SOUTH ARE POSSIBLE ON TUESDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING UNTIL 9 AM CDT MONDAY FOR WIZ005-010>013-018-019- 021. && $$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1152 PM MDT SUN MAR 25 2012 .AVIATION...06Z TAFS CONFIDENCE GROWING THAT STRATUS WILL RETURN TO THE PANHANDLE LATER THIS EVENING. LATEST HRRR MODEL RUN SHOWING CDR...AIA AND SNY GOING DOWN BELOW IFR CONDITIONS IN SOUTHEAST UPSLOPING WINDS AROUND 09Z OR SO. VERY CLOSE T/TD SPREAD ALREADY GETTING SOME FOG DEVELOPMENT AT AIA AND SNY. SO FEEL PRETTY GOOD THAT THEY WILL GO DOWN FROM 09Z TO 15-16Z OR SO. AS FOR THE REST OF THE TAF PERIOD...EXPECT WINDS TO REALLY RAMP UP AS A COLD FRONT APPROACHES CENTRAL WYOMING AROUND NOON TIME MONDAY. ALL AIRPORTS WILL HAVE WIND ISSUES AFTER 18Z OR SO. CLAYCOMB && .PREV DISCUSSION... /ISSUED 611 PM MDT SUN MAR 25 2012/ UPDATE... DENSE CLOUDS HAVE KEPT TEMPERATURES AND GUSTY WINDS DOWN ACROSS AREAS WHERE FUELS ARE REPORTED CURED. COOLER TEMPERATURES AND LESS WINDS HAVE ALLEVIATED ANY FIRE DANGERS TODAY. THUS THE RED FLAG WARNINGS HAVE BEEN CANCELLED A LITTLE WHILE AGO. ATTENTION TURNS TO MONDAY WITH A WIDESPREAD STRONG WIND EVENT UNFOLDING. WENT AHEAD UPGRADED THE FIRE WEATHER WATCHES TO RED FLAG WARNINGS FOR AREAS EAST OF THE LARAMIE RANGE OUT INTO THE PANHANDLE. UPDATES HAVE BEEN SENT. CLAYCOMB AVIATION...00Z TAFS MAIN CONCERN FOR SOUTHEAST WYOMING AND NEBRASKA PANHANDLE AIRPORTS MONDAY LOOK TO BE WINDS. A POWERFAL...YET DRY PACIFIC LOW PRESSURE SYSTEM SET TO MOVE INTO WESTERN WYOMING TONIGHT...CREATING VERY STRONG WINDS ACROSS SOUTHEAST WYOMING BY MORNING. THESE WINDS WILL SPREAD OUT INTO THE PANHANDLE TOMORROW AFTERNOON. STARTUS LOOKS TO RETURN TO THE PANHANDLE OVERNIGHT WITH THE HRRR FORECASTING IFR CEILINGS AROUND 07Z OR SO. HAVE DELAYED ONSET SOME...BUT WILL GET A BETTER GRASP ON THE 06Z TAFS. CLAYCOMB PREV DISCUSSION... /ISSUED 301 PM MDT SUN MAR 25 2012/ SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT... TONIGHT...ANOTHER MILD NIGHT WITH WARM AIRMASS IN PLACE ALONG WITH DECENT MIXING AND LOW LEVEL MOISTURE HANGING IN...ESPECIALLY EAST OF INTERSTATE 25. LOW TEMPERATURES SOME 15 TO 20 DEGREES ABOVE NORMAL. BOUNDARY LAYER RELATIVE HUMIDITY AND LOW LEVEL WINDS BACKING TO SOUTHEAST WILL AID IN FOG AND LOW CLOUD FORMATION NORTH OF A LUSK TO ALLIANCE LINE AFTER MIDNIGHT. MONDAY...IMPRESSIVELY STRONG NEGATIVELY TILTED SHORTWAVE TROUGH MOVES TO EASTERN WYOMING IN THE AFTERNOON AS ITS ASSOCIATED POWERFUL PACIFIC ORIGIN COLD FRONT MOVES QUICKLY WEST TO EAST ACROSS OUR COUNTIES FROM LATE MORNING THROUGH LATE AFTERNOON. ALL FACTORS POINTING TO A WIDESPREAD HIGH WIND EVENT AFTER COLD FRONTAL PASSAGE...THUS WE HAVE UPGRADED THE HIGH WIND WATCH TO A HIGH WIND WARNING DUE TO HIGH CONFIDENCE AND ALSO TO GIVE OUR CUSTOMERS AN EARLY HEADS UP ON THE STRONG WINDS. COMBINATION OF STRONG DOWNWARD MOTION INDICATED ON THE 500-300 MB AND 700-500 MB QG PROGS...ALONG WITH PROGGED SURFACE THROUGH 700 MB GRADIENTS... STRONG COLD AIR ADVECTION AND PERFECT TIMING ON COLD FRONTAL PASSAGE SUGGEST A HIGH LIKELIHOOD OF A WIDESPREAD HIGH WIND EVENT IN THE AFTERNOON AND EARLY EVENING. EVEN 700 MB WINDS PROGGED FROM 50-65 KNOTS AFTER COLD FRONTAL PASSAGE AND THESE WINDS WILL BE TRANSPORTED TO THE SURFACE DUE TO DOWNWARD MOMENTUM TRANSFER FROM SUBSIDENCE AFTER THE SHORTWAVE TROUGH PASSAGE. ALTHOUGH LOW AND MID LEVEL MOISTURE WILL BE QUITE SCANT...THERE SHOULD BE ENOUGH FOR AT LEAST ISOLATED AFTERNOON THUNDERSTORMS NORTH OF A LARAMIE TO CHADRON LINE. QUITE A VARIANCE IN NAM AND GFS PROGGED HIGH TEMPERATURES AT SOME LOCATIONS...WILL BLEND IN THE MIDDLE AND BLEND WITH OUR NEIGHBORING OFFICES FOR THE MOST LIKELY FORECAST. MONDAY NIGHT...WITH THE PROGGED SURFACE THROUGH 700 MB GRADIENT AND STRONG COLD AIR ADVECTION CONTINUING INTO THE EVENING AS WELL AS DECENT DOWNWARD MOTION INDICATED ON THE 500-300 MB AND 700-500 MB QG PROGS...WILL EXTEND THE HIGH WIND WARNING UNTIL 9 PM...THEN WINDS SHOULD SUBSIDE UNDER HIGH WIND CRITERIA...THOUGH WOULD NOT BE SURPRISED TO SEE A FEW LOCATIONS CONTINUE HIGH WINDS BEYOND 9 PM. TUESDAY...ZONAL FLOW ALOFT...WEST TO EAST...AND WEAKER SURFACE THROUGH 700 MB GRADIENTS...ALONG WITH LIMITED LOW AND MID LEVEL MOISTURE WILL PRODUCE ANOTHER MILD AND DRY DAY. TUESDAY NIGHT...LOW AMPLITUDE SHORTWAVE RIDGING ALOFT WILL PROMOTE LIGHT SOUTH TO SOUTHWEST WINDS AND A MILD NIGHT WITH LOW TEMPERATURES ABOUT 10 DEGREES ABOVE NORMAL. LONG TERM...WEDNESDAY THROUGH SUNDAY...THERE ARE SOME DIFFERENCES BETWEEN THE 00Z AND 12Z MEDIUM RANGE MODEL GUIDANCE...BUT NOT SIGNIFICANT FOR MAJOR CHANGES TO THE GOING FORECAST. THE TREND OF UNSEASONABLY MILD TEMPERATURES AND DRY CONDITIONS WILL CONTINUE... WHICH WILL MAINTAIN THE WILDLAND FIRE DANGER. AN UPPER RIDGE WILL MOVE EAST ACROSS THE REGION WEDNESDAY...AND INTO THE PLAINS ON THURSDAY. ON WEDNESDAY...MINIMUM RELATIVE HUMIDITIES FALL TO CRITICAL LEVELS...HOWEVER WINDS EAST OF THE LARAMIE RANGE SHOULD NOT REACH CRITERIA. AREAS ALONG AND WEST OF THE RANGE WILL MEET WIND CRITERIA BUT FUELS ARE NOT READY FOR RAPID FIRE GROWTH. THIS COULD CHANGE DURING THE COURSE OF THE WEEK WITH THE LACK OF MOISTURE AND CONTINUED GUSTY WEST TO SOUTHWEST WINDS. LOW RELATIVE HUMIDITIES ARE EXPECTED THURSDAY AND FRIDAY AFTERNOON...WITH THE GUSTY WINDS AFFECTING THE REMAINDER OF THE EASTERN PLAINS AND ADJACENT WESTERN NEBRASKA PANHANDLE. FOR THE UPCOMING WEEKEND... THE FLOW ALOFT BACKS TO THE SOUTHWEST AND AMPLIFIES IN ADVANCE OF THE NEXT UPPER TROUGH MOVING INTO THE PACIFIC NORTHWEST. A PACIFIC LOW PRESSURE SYSTEM AND COLD FRONT APPROACHES THE REGION SUNDAY... WITH PRECIPITATION SPREADING EAST ACROSS THE CWA SUNDAY NIGHT. AVIATION...18Z TAF ISSUANCE...IFR CEILINGS SLOW TO SCATTER AT SIDNEY...BUT SHOULD DO SO BY MID AFTERNOON AS SOUTH TO SOUTHEAST BOUNDARY LAYER WINDS INCREASE. ELSEWHERE...EXPECT VFR CONDITIONS WITH SCATTERED TO BROKEN HIGH CLOUDS. SOUTHERLY SURFACE WINDS WILL BE BREEZY AT TIMES...ESPECIALLY FOR THE SOUTHEAST WYOMING AIRFIELDS AND SCOTTSBLUFF WHERE GUSTS OF 20 TO 25 KT WILL BE POSSIBLE. LOW LEVEL SOUTHEASTERLY FLOW WILL TRANSPORT SOME MOISTURE INTO THE WESTERN PANHANDLE LATER TONIGHT...WITH THE POSSIBILITY OF MVFR TO LOCAL IFR CEILINGS AND VISIBILITIES IN LOW STRATUS AND PATCHY FOG. BEST CHANCE FOR THESE CONDITIONS WILL BE FROM CHADRON THROUGH ALLIANCE AND SIDNEY. FIRE WEATHER...MINIMUM AFTERNOON HUMIDITIES TODAY WILL RANGE FROM 10 TO 20 PERCENT ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS UP TO 30 MPH. CRITICAL FIRE WEATHER CONDITIONS WILL OCCUR ON MONDAY AS A STRONG PACIFIC ORIGIN COLD FRONT SWEEPS ACROSS THE DISTRICT FROM LATE MORNING THROUGH AFTERNOON...ALONG WITH STRONG WINDS AND LOW RELATIVE HUMIDITIES. WINDS WILL SUBSIDE MONDAY EVENING. MORE NEAR CRITICAL FIRE WEATHER CONDITIONS WILL OCCUR TUESDAY INTO THE WEEKEND WITH LOW RELATIVE HUMIDITIES AND GUSTY WINDS SOME OF THE AFTERNOONS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...RED FLAG WARNING FROM 10 AM MONDAY TO 7 PM MONDAY FOR WYZ101- WYZ102-WYZ106-WYZ107-WYZ108-WYZ116-WYZ117-WYZ118-WYZ119. HIGH WIND WARNING FROM 2 PM MONDAY TO 9 PM MONDAY FOR WYZ101- WYZ102-WYZ106-WYZ107-WYZ108-WYZ116-WYZ117-WYZ118-WYZ119. HIGH WIND WARNING FROM 11 AM MONDAY TO 9 PM MONDAY FOR WYZ104- WYZ105-WYZ109-WYZ110-WYZ111-WYZ113-WYZ115. NE...HIGH WIND WARNING FROM 2 PM MONDAY TO 9 PM MONDAY FOR NEZ002- NEZ003-NEZ019-NEZ020-NEZ021-NEZ054-NEZ055-NEZ095-NEZ096. RED FLAG WARNING FROM 10 AM MONDAY TO 7 PM MONDAY FOR NEZ002- NEZ003-NEZ019-NEZ020-NEZ021-NEZ054-NEZ055-NEZ095-NEZ096. && $$ SHORT TERM/FIRE WEATHER...RUBIN LONG TERM/AVIATION...JAMSKI
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1139 PM CDT TUE MAR 27 2012 .UPDATE 28/06Z AVIATION DISCUSSION... .SHORT TERM /TONIGHT/... REMOVED ADV FROM AFD...REST OF FORECAST LOOKS ON TRACK. /REV .PREVIOUS SHORT TERM /TONIGHT/... SFC TROUGH AXIS ASSOCIATED WITH NORTHERN MINNESOTA LOW PRESSURE IS EXTENDING SOUTH THROUGH CNTRL IA THIS AFTERNOON. AIRMASS BEHIND THE TROUGH HAS DOWNSLOPE PROPERTIES INITIALLY REMAINING MILD YET MUCH DRIER WITH DEWPOINTS IN THE 30S ADVECTING IN. DEWPOINTS REMAIN IN THE MID TO UPPER 50S OVER THE SOUTHEAST IN ADVANCE OF THE SYSTEM. UPPER PV ANOMALY OVER SRN SOUTH DAKOTA WILL TRACK EAST AND WILL BE OVER FAR SOUTH CENTRAL MINNESOTA BY 00Z. SOME ASSOCIATED KINEMATIC FORCING WILL OCCUR TO THE SOUTHEAST OF THE SYSTEM. CURRENTLY INSTABILITY HAS BEEN INCREASING OVER THE SOUTHEAST THIRD OF THE WARNING AREA. RUC AND NAM PROXIMITY SOUNDINGS SHOW A WEAK CAP LOCATED NEAR 750 MB WHICH DOES NOT ERODE UNTIL AFTER 23Z WITH THE ARRIVAL OF MID LEVEL COOLING AND KINEMATICS WITH THE MID LEVEL WAVE. POSSIBLE A STORM OR TWO MAY FIRE OVER THE FAR SOUTHEAST BUT OVERALL THE CURRENT INSTABILITY IS NOT EXPECTED TO BE REALIZED UNTIL IT PUSHES SOUTHEAST OF THE STATE. A FEW SITES NEAR WIND ADVISORY CRITERIA ATTM MOMENT THOUGH OVERALL MOST ARE BELOW. HAVE TRIMMED PORTIONS OF THE ADVISORY BUT HAVE KEPT THE NORTH TO KEEP COLLABORATED WITH SURROUNDING SITES. HAVE MOVED END TIME UP TO 7 PM WITH WINDS DIMINISHING WITH THE LOSS OF DAY TIME HEATING AND MIXING. .LONG TERM /WEDNESDAY THROUGH TUESDAY/... TWO PRIMARY SYSTEMS TO CONTEND WITH IN THIS PERIOD. WEAK RIDGE APPROACHING THE MO VALLEY PRECEDING SHORT WAVE EJECTING OUT OF CURRENT EAST PACIFIC LONG WAVE THROUGH. THIS WAVE SHOULD REACH THE HIGH PLAINS LATE TOMORROW WHICH...COMBINED WITH THE DEPARTING RIDGE...WILL INCREASE WARM ADVECTION INTO THE MO VALLEY. THETA-E ADVECTION ADVANCES INTO SWRN IA COINCIDENT WITH ELEVATED CAPE GRADIENT. ALTHOUGH BEST ISENTROPIC LIFT WILL REMAIN NW INTO THE DAKOTAS AND ERN MN...MODEL 300K SURFACES NEAR INVERSION TOP SUGGEST THERE WILL BE SUFFICIENT LIFT AND SATURATION EARLY THU MORNING FOR CONVECTION TO DEVELOP AND LINGER INTO THE MORNING. ATTENTION THEN TURNS UPSTREAM WHERE BOTH NAM AND GFS DEPICT 1500-2500 J/KG MLCAPES BECOMING UNCAPPED JUST WEST OF MO RIVER DURING PEAK HEATING. LOW LEVEL CONVERGENCE IS SOMEWHAT WEAK...BUT THIS FAVORABLE THERMODYNAMIC ENVIRONMENT AIDED BY LARGE SCALE FORCING WITH WAVE SHOULD BE SUFFICIENT FOR A MCS TO DEVELOP AND THEN LIKELY WEAKEN INTO THE EVENING WITH LOSS OF HEATING. REGARDING SEVERE POTENTIAL DURING EVENT...ELEVATED NATURE AND FAIRLY WEAK UNIDIRECTIONAL FLOW IN EFFECTIVE INFLOW LAYER EARLY THU SHOULD DIMINISH THIS SEVERE POTENTIAL. MOST LIKELY SEVERE CHANCES LOOK TO BE DURING PEAK HEATING TAPPING BETTER 0-6KM SHEAR LATE AFTERNOON AND EVENING WHEN AND IF CONVECTION BECOMES SURFACE BASED. WEAK NORTHERN STREAM WAVE HAS RESULTED IN SLIGHT CHANCES FRI NIGHT WITH NEXT LARGE SYSTEM IN THE OFFING EARLY NEXT WEEK. MODELS HAVE COME INTO SOMEWHAT BETTER AGREEMENT WITH RESPECT TO TIMING SUGGESTING FORCING INCREASING SUN NIGHT FOLLOWED BY FRONTAL PASSAGE LATE SUNDAY AFTERNOON OR SUNDAY NIGHT. BEST SHEAR SEEMS TO REMAIN TO OUR SOUTH AND INSTABILITY IS UNREMARKABLE AT THIS POINT SO DO NOT SEE ELEVATED SEVERE THREAT WITH THIS SYSTEM AT THE MOMENT. DIRTY NW FLOW WILL KEPT LOW CHANCES GOING IN ITS WAKE THROUGH TUE. TEMPS WILL DROP SHARPLY BEHIND THIS...BUT ONLY DOWN TO ABOUT CLIMO. NO FREEZING TEMPS OR FROST ANTICIPATED THROUGH DAY 7. && .AVIATION...28/06Z VFR TO UNLIMITED CIGS EXPECTED FOR THE NIGHT WITH SCT150 WITH SOME MID LEVEL CLOUDS TAKING AIM AT SOUTHERN REGIONS OVERNIGHT. OTHERWISE WINDS HAVE RELAXED...BUT WILL INCREASE AS EXPECTED AT 15Z WITH MIXING ONCE AGAIN THROUGH 23Z. AFT 23Z...CIGS WILL LOWER ACROSS THE WEST BUT REMAIN VFR. NORTHWEST WINDS WILL GIVE WAY TO LIGHT EAST WINDS PRIOR TO INCREASING RAPIDLY 6 TO 12 HOURS AFT END OF TAF PERIOD. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE && $$ SHORT TERM...DONAVON/REV AVIATION...REV LONG TERM...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
111 AM MDT WED MAR 28 2012 .UPDATE... ISSUED AT 848 PM MDT TUE MAR 27 2012 JUST COMPLETED AN UPDATE. ADJUSTED CLOUD COVER BEST ON LATEST SATELLITE MODEL DATA. MODELS HAVE BACKED OFF ON THE CLOUD COVER THE REST OF THE NIGHT AND DECREASED. LATEST HRRR BRINGS SOME FOG CLOSE TO THE SOUTHERN PORTION OF THE FORECAST AREA. INSERTED PATCHY FOG IN THIS AREA FROM 09Z TO 14Z. ADJUSTED THE DEWPOINTS/WINDS PER LATEST RUC/HRRR. 00Z SOUNDINGS AND NAM WOULD INDICATE THAT EVEN THOUGH THERE IS ELEVATED INSTABILITY...THE SOUNDINGS ARE VERY VERY DRY AND CAPPED ALOFT. SO LEFT ANY MENTION OF THUNDERSTORMS THE REST OF THE NIGHT. UPDATE ISSUED AT 536 PM MDT TUE MAR 27 2012 CANCELLED RED FLAG WARNING EARLY AS WINDS HAVE DROPPED OFF DRAMATICALLY. CURRENTLY RATHER THICK HIGH LEVEL CLOUD COVER IS DRAPED ACROSS THE AREA. THIS IS BEING CAUSE BY RIGHT REAR QUADRANT OF MID/UPPER JET THAT REMAINS/MOVES ACROSS THE AREA THROUGH MOST OF THE NIGHT. SO INCREASED CLOUD COVER...ESPECIALLY FOR THIS EVENING. WIND FIELD IS RATHER LIGHT RIGHT NOW WITH RUC/HRRR CATCHING THE WIND FIELD NICELY SO ADJUSTED USING THEM. SOMETHING TO WATCH FOR LATER TONIGHT. THERE WILL BE A RIGHT REAR QUADRANT OF THE JET NEAR THE EASTERN PORTION OF THE FORECAST AREA WITH AN APPROACHING SHORTWAVE TROUGH. MODELS SHOWING A RATHER HIGH AMOUNT OF ELEVATED INSTABILITY. HOWEVER...THE CINH LOOKS STRONG BUT WITH SOME POCKETS OF WEAKNESS. QUESTION WILL THERE BE ENOUGH MOISTURE IN THE COLUMN TO GET THIS FULLY REALIZED. WILL CONTINUE TO WATCH THROUGH THE EVENING AND LOOK AT LATEST MODEL DATA/00Z SOUNDINGS TO SEE IF NEED TO ADD SOME THUNDERSTORMS FOR LATER TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 200 PM MDT TUE MAR 27 2012 WEAK UPPER LEVEL RIDGING WILL OCCUR ACROSS THE CENTRAL PLAINS TONIGHT AND WEDNESDAY BEFORE SEVERAL WEAK SHORT WAVE TROUGHS FLATTEN IT OUT WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL CONTINUE UNSEASONABLY MILD FOR LATE MARCH UNDER THIS REGIME. THE WEAK COLD FRONT WHICH PASSED THROUGH THE AREA LAST NIGHT IS APPROACHING THE WICHITA AREA WHERE IT WILL BEGIN TO STALL. SURFACE DEWPOINTS IN THE MIDDLE 50S ARE BEING PUSHED INTO SOUTHEAST KANSAS IN THE SHORT TERM AS A RESULT OF THE FRONTAL PASSAGE...BUT AS A LEE TROUGH AND RETURN SURFACE FLOW SET UP DURING THE DAY WEDNESDAY...LOW LEVEL MOISTURE WILL RAPIDLY RETURN TO NORTHWEST KANSAS. FORECAST SOUNDINGS HINT AT A STRATUS/STRATOCU DECK BY MIDDAY TOMORROW MOVING ACROSS OUR EASTERN COUNTIES. CANNOT RULE OUT SOME LIGHT SHOWERS AT THAT TIME GIVEN 700 MB WARM ADVECTION PATTERN. HAVE INCLUDED LOW POPS AND SHOWERS MAINLY FOR WEDNESDAY AFTERNOON IN THIS AREA. KEPT THUNDER OUT FOR THE TIME BEING GIVEN THE ANTICIPATED CLOUD COVER AND LACK OF GOOD INSTABILITY. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 101 AM MDT WED MAR 28 2012 UPPER RIDGE AXIS WILL BE OVER THE REGION ON SATURDAY WITH WARM AND DRY CONDITIONS. HOWEVER IT WILL QUICKLY BREAK DOWN WITH APPROACH OF SHORTWAVE TROUGH ON SUNDAY. IT IS FORECAST TO EJECT ACROSS THE NORTHERN ROCKIES AND ADJACENT PLAINS...TOO FAR NORTH TO BRING PRECIPITATION CHANCES. HOWEVER WITH A JET MAX FORECAST TO ROTATE THROUGH THE BASE OF THE TROUGH OVER THE CENTRAL HIGH PLAINS IT COULD EASILY TURN INTO OUR NEXT HIGH WIND AND FIRE WEATHER EVENT. COOLER TEMPERATURES WILL FOLLOW IN ITS WAKE FOR MONDAY AND TUESDAY...BUT AS RIDGE REBUILDS TEMPERATURES WILL BEGIN WARMING AGAIN FOR THE MIDDLE OF THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1051 PM MDT TUE MAR 27 2012 INTERESTING SET OF TAFS. LOT OF LOW LEVEL MOISTURE NOT TOO FAR TO OUR SOUTH AND WILL EVENTUALLY GET DRAWN UP INTO THE AREA. MODELS HAVE CHANGED THEIR TUNE A LITTLE AND NOW APPEAR MORE AGGRESSIVE IN BRINGING UP LOWER CEILINGS. CONSIDERING THE WEAK LOW LEVEL FLOW WHICH EVENTUALLY TRANSITIONS TO AN EASTERLY DIRECTION...DO NOT THINK THE MODELS ARE UNREASONABLE IN THEIR DEPICTION. AS A RESULT BY LATER TONIGHT THROUGH THE DAY TOMORROW...THE CEILINGS LOWER NEAR TO MVFR OR INTO THE MVFR CATEGORY. THERE APPEARS TO BE SOME CLEARING LATER IN THE DAY BUT THAT WILL BE SHORT LIVED AS MORE ABUNDANT LOW LEVEL MOISTURE GETS DRAWN UP INTO THE AREA NEAR THE END OR JUST AFTER THE END OF THIS PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...NONE. KS...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...DLF LONG TERM....024 AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1056 PM MDT TUE MAR 27 2012 .UPDATE... ISSUED AT 848 PM MDT TUE MAR 27 2012 JUST COMPLETED AN UPDATE. ADJUSTED CLOUD COVER BEST ON LATEST SATELLITE MODEL DATA. MODELS HAVE BACKED OFF ON THE CLOUD COVER THE REST OF THE NIGHT AND DECREASED. LATEST HRRR BRINGS SOME FOG CLOSE TO THE SOUTHERN PORTION OF THE FORECAST AREA. INSERTED PATCHY FOG IN THIS AREA FROM 09Z TO 14Z. ADJUSTED THE DEWPOINTS/WINDS PER LATEST RUC/HRRR. 00Z SOUNDINGS AND NAM WOULD INDICATE THAT EVEN THOUGH THERE IS ELEVATED INSTABILITY...THE SOUNDINGS ARE VERY VERY DRY AND CAPPED ALOFT. SO LEFT ANY MENTION OF THUNDERSTORMS THE REST OF THE NIGHT. UPDATE ISSUED AT 536 PM MDT TUE MAR 27 2012 CANCELLED RED FLAG WARNING EARLY AS WINDS HAVE DROPPED OFF DRAMATICALLY. CURRENTLY RATHER THICK HIGH LEVEL CLOUD COVER IS DRAPED ACROSS THE AREA. THIS IS BEING CAUSE BY RIGHT REAR QUADRANT OF MID/UPPER JET THAT REMAINS/MOVES ACROSS THE AREA THROUGH MOST OF THE NIGHT. SO INCREASED CLOUD COVER...ESPECIALLY FOR THIS EVENING. WIND FIELD IS RATHER LIGHT RIGHT NOW WITH RUC/HRRR CATCHING THE WIND FIELD NICELY SO ADJUSTED USING THEM. SOMETHING TO WATCH FOR LATER TONIGHT. THERE WILL BE A RIGHT REAR QUADRANT OF THE JET NEAR THE EASTERN PORTION OF THE FORECAST AREA WITH AN APPROACHING SHORTWAVE TROUGH. MODELS SHOWING A RATHER HIGH AMOUNT OF ELEVATED INSTABILITY. HOWEVER...THE CINH LOOKS STRONG BUT WITH SOME POCKETS OF WEAKNESS. QUESTION WILL THERE BE ENOUGH MOISTURE IN THE COLUMN TO GET THIS FULLY REALIZED. WILL CONTINUE TO WATCH THROUGH THE EVENING AND LOOK AT LATEST MODEL DATA/00Z SOUNDINGS TO SEE IF NEED TO ADD SOME THUNDERSTORMS FOR LATER TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 200 PM MDT TUE MAR 27 2012 WEAK UPPER LEVEL RIDGING WILL OCCUR ACROSS THE CENTRAL PLAINS TONIGHT AND WEDNESDAY BEFORE SEVERAL WEAK SHORT WAVE TROUGHS FLATTEN IT OUT WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL CONTINUE UNSEASONABLY MILD FOR LATE MARCH UNDER THIS REGIME. THE WEAK COLD FRONT WHICH PASSED THROUGH THE AREA LAST NIGHT IS APPROACHING THE WICHITA AREA WHERE IT WILL BEGIN TO STALL. SURFACE DEWPOINTS IN THE MIDDLE 50S ARE BEING PUSHED INTO SOUTHEAST KANSAS IN THE SHORT TERM AS A RESULT OF THE FRONTAL PASSAGE...BUT AS A LEE TROUGH AND RETURN SURFACE FLOW SET UP DURING THE DAY WEDNESDAY...LOW LEVEL MOISTURE WILL RAPIDLY RETURN TO NORTHWEST KANSAS. FORECAST SOUNDINGS HINT AT A STRATUS/STRATOCU DECK BY MIDDAY TOMORROW MOVING ACROSS OUR EASTERN COUNTIES. CANNOT RULE OUT SOME LIGHT SHOWERS AT THAT TIME GIVEN 700 MB WARM ADVECTION PATTERN. HAVE INCLUDED LOW POPS AND SHOWERS MAINLY FOR WEDNESDAY AFTERNOON IN THIS AREA. KEPT THUNDER OUT FOR THE TIME BEING GIVEN THE ANTICIPATED CLOUD COVER AND LACK OF GOOD INSTABILITY. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 200 PM MDT TUE MAR 27 2012 WEDNESDAY NIGHT-THURSDAY...LOW CLOUDS AND FOG EXPECTED WEDNESDAY NIGHT SLOWLY DECREASING IN COVERAGE THURSDAY MORNING. MAY HAVE A BRIEF PERIOD NORTH WINDS GUSTING 30 MPH ALONG AND WEST OF THE CO/KS BORDER DURING THE AFTERNOON AS A FRONT MOVES THROUGH. HIGH TEMPERATURES IN THE 70S. FRIDAY...DRY WITH HIGHS IN THE MID 70S TO AROUND 80. SATURDAY-MONDAY...ATTENTION TURNS TO DEVELOPING UPPER TROUGH WHICH BY 00Z SUNDAY SHOULD BE COMING ASHORE ALONG THE WEST COAST AND MOVING THROUGH THE FORECAST AREA BY 00Z MONDAY. BY 00Z TUESDAY THE SYSTEM IS EXPECTED TO LIFT NORTHEAST. SOUTHERLY WINDS WILL SLOWLY INCREASE THROUGH THE DAY SATURDAY AND MAY BECOME BREEZY ALONG AND WEST OF THE CO/KS BORDER. ON SUNDAY A COLD FRONT MOVES IN ASSOCIATED WITH THE UPPER TROUGH. WINDS WILL SHIFT TO THE NORTHWEST AND INCREASE IN SPEED WITH WINDY CONDITIONS EXPECTED. THESE GUSTY NORTHWEST WINDS WILL CONTINUE SUNDAY NIGHT AND MONDAY WITH GUSTS TO 45 MPH POSSIBLE. A WIND ADVISORY MAY BE NEEDED. HIGH TEMPERATURES SATURDAY IN THE 80S FALLING INTO THE LOW 70S WEST OF THE CO/KS BORDER SUNDAY...MID TO UPPER 70S EAST. ON MONDAY EXPECTED MID 50S TO LOW 60S WHICH IS RIGHT NEAR NORMAL FOR LATE MARCH. PRECIPITATION CHANCES WILL BE CONFINED TO SUNDAY AFTERNOON AND SUNDAY NIGHT WHERE SOME RAIN SHOWERS ARE POSSIBLE. TUESDAY...BROAD UPPER RIDGE REDEVELOPS AS SUNDAYS SYSTEM LIFTS TOWARD THE GREAT LAKES AND ANOTHER STORM MOVES TOWARD THE PACIFIC NORTHWEST. AFTERNOON HIGHS GENERALLY IN THE 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1051 PM MDT TUE MAR 27 2012 INTERESTING SET OF TAFS. LOT OF LOW LEVEL MOISTURE NOT TOO FAR TO OUR SOUTH AND WILL EVENTUALLY GET DRAWN UP INTO THE AREA. MODELS HAVE CHANGED THEIR TUNE A LITTLE AND NOW APPEAR MORE AGGRESSIVE IN BRINGING UP LOWER CEILINGS. CONSIDERING THE WEAK LOW LEVEL FLOW WHICH EVENTUALLY TRANSITIONS TO AN EASTERLY DIRECTION...DO NOT THINK THE MODELS ARE UNREASONABLE IN THEIR DEPICTION. AS A RESULT BY LATER TONIGHT THROUGH THE DAY TOMORROW...THE CEILINGS LOWER NEAR TO MVFR OR INTO THE MVFR CATEGORY. THERE APPEARS TO BE SOME CLEARING LATER IN THE DAY BUT THAT WILL BE SHORT LIVED AS MORE ABUNDANT LOW LEVEL MOISTURE GETS DRAWN UP INTO THE AREA NEAR THE END OR JUST AFTER THE END OF THIS PERIOD. && .FIRE WEATHER... ISSUED AT 200 PM MDT TUE MAR 27 2012 THURSDAY AFTERNOON...THE COMBINATION OF RELATIVE HUMIDITY BELOW 20 PERCENT AND NORTH WINDS GUSTING TO 30 MPH MAY CREATE CRITICAL FIRE WEATHER CONDITIONS GENERALLY WEST OF A LINE FROM BENKELMAN NEBRASKA TO GOODLAND. SUNDAY AFTERNOON...RELATIVE HUMIDITY WILL BE BELOW 20 PERCENT. WEST TO SOUTHWEST WINDS OF 15 TO 20 MPH WITH HIGHER GUSTS MID TO LATE AFTERNOON WILL SHIFT TO THE NORTHWEST AND GUST AROUND 30 MPH LATE IN THE DAY TO CREATE CRITICAL FIRE WEATHER CONDITIONS...GENERALLY WEST OF A LINE FROM TRENTON NEBRASKA TO GOODLAND AND TRIBUNE KANSAS. MONDAY AFTERNOON AND TUESDAY AFTERNOON...CRITICAL FIRE WEATHER CONDITIONS EXPECTED ACROSS THE ENTIRE FORECAST AREA AS NORTHWEST WINDS GUSTING IN THE 35 TO 45 MPH RANGE COMBINE WITH AFTERNOON HUMIDITY BELOW 20 PERCENT. && .GLD WATCHES/WARNINGS/ADVISORIES... CO...NONE. KS...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...DLF LONG TERM....007 AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
132 AM EDT WED MAR 28 2012 .SYNOPSIS... ISSUED AT 408 PM EDT TUE MAR 27 2012 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW POTENT NEGATIVELY TILTED SHRTWV/STACKED LO MOVING ENEWD THRU NRN MN ON TOP OF MEAN RDG OVER THE SE CONUS. PCPN/WARM CONVEYOR BELT WELL E OF THE LO HAS MOVED E OF THE CWA...BUT LO CLDS LINGER IN THE RELATIVELY MOIST LYR ASSOCIATED WITH SHARP WAD INVRN DEPICTED ON THE 12Z RAOBS. SKIES ARE MOCLR OVER MN UNDER THE DRY SLOT/JET SURGE REGION OF THE LO...AND TEMPS HAVE RISEN WELL INTO THE 50S AND 60S IN THAT AREA. DESPITE THIS SHARP WAD STABILITY...GUSTY S WINDS UP TO 50 MPH UNDER SHARP PRES GRADIENT BTWN THE LO AND RETREATING HI PRES OVER SE ONTARIO HAVE IMPACTED LOCATIONS NEAR THE LK SUP SHORE...PROMPTING ISSUANCE OF WIND ADVY. IN FACT...THE 12Z MPX RAOB INDICATED A WIND SPEED OF 61KTS AT 3K FT AGL WITHIN THE STABLE INVRN LYR. THE S WIND OFF THE RELATIVELY CHILLY LK MI WATERS HAVE ENHANCED THE LLVL STABILITY AND PREVENTED THE WINDS IN THAT AREA FM BEING AS STRONG AS NEAR LK SUP. FARTHER TO THE W...DEEP WRAP ARND MSTR SHOWN ON THE 12Z BISMARCK RAOB IS MOVING INTO NW NW IN THE WAKE OF THE DEPARTING LO. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 408 PM EDT TUE MAR 27 2012 MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON WINDS/CLD TRENDS AND PSBL WRAP ARND -SHRA AS MN LO MOVES ACRS NRN LK SUP AND INTO SE ONTARIO ON WED. TNGT...SHRTWV/CLOSED LO IN MN ARE PROGGED TO MOVE INTO SE ONTARIO JUST NE OF THE SAULT BY 12Z WED. AS THE PRES GRADIENT WEAKENS AT LEAST TEMPORARILY WITH THE APRCH OF THE SFC LO...EXPECT WINDS TO DIMINISH LATE THIS AFTN/EARLY EVNG. SO WL LET THE GOING WIND ADVY EXPIRE AT 21Z AS SCHEDULED. ALTHOUGH THE EARLY EVNG WL BE PCPN FREE FOR THE MOST PART UNDER DRY SLOT...MORE CLDS/SCT -SHRA WL ARRIVE FM THE W AS THE WRAP ARND MSTR ACCOMPANYING THE EWARD MOVING LO PRES SLIDES INTO THE UPR LKS. STRONG W H925 WINDS UP TO 40-50 KTS ON THE WRN FLANK OF THE LO WL ADVECT MUCH COOLER AIR INTO THE AREA...WITH H85 TEMPS FCST AS LO AS -2C OR -3C OVER THE W BY 12Z...BUT FCST WBLB ZERO HGT WELL ABV 1K FT SUGS THE PCPN WL REMAIN MAINLY IN THE FORM OF RA EXCEPT OVER THE HIER TERRAIN OF THE W LATE. EXPECT STRONG W WINDS TO IMPACT THE W LATE AS WELL...WITH WIND GUSTS APRCHG ADVY LVL AGAIN OVER THE FAR W S OF CMX WHERE THE CORE OF STRONGEST WINDS COINCIDES WITH THE INCOMING H85 THERMAL TROF. CONSIDERED EXTENDING WIND ADVY FOR THE KEWEENAW...BUT AXIS OF STRONGER WINDS POINTING TOWARD THIS EXPOSED AREA DOES NOT COINCIDE WITH THERMAL TROFFING/ REDUCED STABILITY THAT WOULD ENHANCE MIXING. WED...AS THE CLOSED LO TO THE E MOVES FARTHER AWAY...SFC HI PRES RDG WL BLD INTO THE AREA UNDER RISING H5 AHEAD OF PROGRESSIVE UPR RDG IN THE PLAINS. MRNG -SHRA...MIXED WITH SN PER LOWER WBLB ZERO HGTS AS H85 TEMPS FALL TO ARND -5C...MAINLY IN THE UPSLOPE AREAS OVER THE NRN TIER WL DIMINISH WITH TIME UNDER NEGATIVE DYNAMICS/MID LVL DRYING AND GRDLY MORE ACYC FLOW... BUT FCST SDNGS SUG PLENTY OF LO CLD WL LINGER...SO TENDED TOWARD THE LOWER END OF GUIDANCE FOR TEMPS. AS THE LO MOVES AWAY AND HI PRES MOVES TOWARD THE AREA...THE WINDS WL DIMINISH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 408 PM EDT TUE MAR 27 2012 WED NIGHT...H925 TEMPS AROUND -6C WILL LEAD TO ENOUGH LK INSTABILITY TO KEEP CLOUDS GOING THROUGH MUCH OF THE NIGHT FOR LOCATIONS FAVORED BY VEERING N TO NE WINDS NEAR LK SUPERIOR. LINGERED SLIGHT CHANCES THROUGH THE EVENING FOR THE NRLY FAVORED LOCATIONS BEFORE DIMINISHING IT OVERNIGHT. DID HOLD ON TO THE SLIGHTS LONGER FOR THE UPSLOPE LOCATIONS IN NCNTRL UPPER MI...ALTHOUGH THE LOWERING INVERSION WILL LIMIT CLOUD DEPTH. THURS SHOULD BE A SIMILAR DAY TO YESTERDAY WITH HUDSON BAY HIGH PRESSURE RIDGE OVER UPPER MI. NE WINDS WILL PULL DRIER AIR INTO UPPER MI AND LEAD TO A MOSTLY SUNNY DAY OVER THE EAST HALF. FARTHER WEST...MID CLOUDS WILL BE WORKING OVER THE AREA THROUGH THE AFTERNOON...ALONG WITH SOME SHOWERS OVER WRN LK SUPERIOR...AHEAD OF THE APPROACHING SHORTWAVE. HIGHS WILL BE WARMEST INTERIOR AWAY FROM THE LK SUPERIOR INFLUENCE...WHICH WILL ALLOW FOR DEEPER MIXING AND HIGHS RISING INTO THE MID-UPPER 40S. OTHERWISE...LOCATIONS NEAR LAKE SUPERIOR WILL BE IN THE UPPER 30S AND LOWER 40S. DEWPOINTS ARE THE MAIN ADJUSTMENT TO THE FORECAST...AS MODELS ARE COMING INTO BETTER AGREEMENT WITH ML DEWPOINTS FALLING INTO THE SINGLE DIGITS ABOVE ZERO OVER THE ERN CWA. WILL DROP TD VALUES AGAIN SEVERAL DEGREES OVER THE ERN CWA INTO THE UPPER TEENS. MAY NEED TO DROP THEM EVEN MORE...SINCE MIXED LAYER DEWPOINTS VERIFIED FAIRLY WELL YESTERDAY. THURS NIGHT...CLEAR INITIALLY AND WITH THE LIGHT WINDS OVER THE ERN CWA...SHOULD SEE A QUICK FALL IN TEMPS DURING THE EVENING HOURS. BUT INCREASING CLOUDS AHEAD OF THE APPROACHING SHORTWAVE WILL CAUSE THE TEMPS TO RISE THROUGH THE NIGHT. TRIED TO SHOW A QUICK DROP IN THE EVENING...BUT UNSURE THE AMOUNT OF WARMING WITH LIMITED WINDS AND MAINLY MID-HIGH CLOUDS...SO HAVE HELD THEM STEADY. SHOWERS ENTERING THE WRN HALF OF THE CWA DURING THE OVERNIGHT HOURS. ASSOCIATED WITH H850-700 WAA IN THE EVENING...WHICH THEN FOCUSES FARTHER S THROUGH THE OVERNIGHT HOURS. THIS SHOULD DIMINISH THE COVERAGE OF THE SHOWERS AS THEY PUSH E. PTYPE IS TRICKY SINCE IT WILL BE FALLING AS SNOW...BUT THEN AN ISOTHERMAL LAYER AT 0C LOOKS TO SETUP FROM 2-6KFT BEFORE NEAR SFC TEMPS BELOW 2KFT WILL BE ABOVE FREEZING. THIS CREATES A SNOW/RAIN MIX SCENARIO AND SMALL DIFFERENCES IN THE THERMAL PROFILE WILL DETERMINE PCPN TYPE. THUS...WENT WITH A RAIN/SNOW MIX OVER UPPER MI...WITH BETTER SNOW CHANCES TO THE NE HALF. FRI...MODELS BECOMING MORE CONSISTENT ON THE BULK OF THE PCPN GOING S OF THE CWA WITH THE SHORTWAVE WEAKENING AS IT TRIES TO PUSH THROUGH THE UPPER RIDGE AND FOCUSING OF THE BETTER H850-700 WAA FARTHER SE OVER LK MI AND LOWER MI. THEREFORE...HAVE A DIMINISHING TREND OVER THE ERN CWA THROUGH THE DAY DUE TO THE PERSISTENT LLVL DRY AIR FROM THE HUDSON BAY HIGH. SHOULD BE A MIX OF RAIN/SNOW IN THE MORNING BEFORE DAYTIME HEATING WOULD CHANGE ANY LINGERING PCPN TO RAIN. EXTENDED /FRIDAY NIGHT THROUGH TUESDAY/... HPC FOLLOWED A 00Z GFS/ECMWF ENS MEAN FOR DAYS 5-7...SINCE THERE IS DECENT CONSISTENCY IN THE TROUGH MOVING OUT OF THE WRN CONUS DURING THAT TIMEFRAME. ANOTHER SHORTWAVE MOVES THROUGH THE UPPER GREAT LKS FOR FRI NIGHT INTO SAT. MOISTURE IS FAIRLY LIMITED...ALONG WITH H850-700 Q-VECTOR CONV...SO THINK OVERALL PCPN CHANCES WILL BE LIMITED. UPPER RIDGE BUILDS OVER THE AREA ON SAT NIGHT INTO SUN NIGHT IN RESPONSE TO UPPER TROUGH OVER THE WRN CONUS SHIFTING INTO THE PLAINS STATES. DETERMINISTIC RUNS STILL DIFFERING IN THE INTENSITY/AMPLITUDE OF THIS TROUGH...WITH THE 00Z GFS MUCH DEEPER AND THE 00Z ECMWF BROADER AND OVER THE CNTRL/NRN PLAINS. 12Z GFS HAS TRENDED TOWARDS THE 00Z ECMWF AND WILL FOLLOW THE HPC SOLN AND HAVE THE BROAD SFC LOW OVER THE CNTRL/NRN PLAINS ON SUN SLIDING SE THROUGH THE UPPER MISS VALLEY AND LOWER GREAT LKS THROUGH TUES. BEFORE THAT...WARM FRONT LOOKS TO SETUP SOMEWHERE OVER THE UPPER GREAT LKS OR SRN ONTARIO...WHICH WOULD HAVE A LARGE AFFECT ON HIGHS. DIFFERENCES IN MODEL SOLNS GIVE UNCERTAINTY IN TEMPS FOR SUN...AS H850 TEMPS RANGE FROM 7-14C. MAY NOT MIX QUITE THAT HIGH...BUT MIXING TO H900 WOULD STILL YIELD HIGHS IN THE 60S. SO HAVE BUMPED UP THE EXISTING FORECAST A FEW DEGREES. HEADING INTO SUN NIGHT THROUGH TUES...AREA WILL BE ON THE NRN FRINGES OF THE SFC LOW FEATURES. IF THE LOW TRENDS TOWARDS THE 00Z GFS...WILL LIKELY BE DRY...BUT IF THE 00Z ECMWF AND 12Z GFS ARE CORRECT WE/LL HAVE BETTER SHOT OF SEEING PCPN. DON/T SEE ANY REASON TO GO ANYTHING MORE THAN LOW END CHANCES AND WILL KEEP THE PCPN AS RAIN WITH THE ABUNDANT WARM AIR REMAINING OVER THE AREA. AS THIS UPPER TROUGH SHIFTS E FOR THE END OF THE WEEK...COULD SEE A TRANSITION TO A BELOW NORMAL TEMPERATURE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 131 AM EDT WED MAR 28 2012 EXPECT STRONG WEST WINDS IN THE WAKE OF A SFC TROUGH/COLD FRONT AT KIWD AND KCMX WITH GUSTS OF 30 TO 35KTS EXPECTED THROUGH TONIGHT...ESPECIALLY AT KCMX. WITH COLDER AIR MOVING IN BEHIND THE FRONT...LOW CLOUDS IN THE MVFR TO OCCASIONAL IFR RANGE ALONG WITH LAKE EFFECT RAIN SHOWERS WILL ALSO MOVE INTO KIWD AND KCMX. IT MAY GET COLD ENOUGH AT KIWD FOR SOME SNOW TO MIX IN WITH THE RAIN LATE TONIGHT AND WED MORNING. MVFR CLOUD DECK WILL ALSO MOVE INTO KSAW LATE TONIGHT BUT RAIN SHOWERS SHOULD GENERALLY HOLD OFF UNTIL AFT 12Z WED WHEN WINDS VEER NW. WINDS WILL DIMINISH AND CIGS SHOULD IMPROVE...ESPECIALLY FM THE WEST LATE WED AS A HIGH PRESSURE RIDGE BUILDS IN FROM NRN ONTARIO. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 408 PM EDT TUE MAR 27 2012 ALTHOUGH THE GOING S GALES OVER THE E HALF OF LK SUP WILL DIMINISH BY EARLY THIS EVENING AS LO PRES IN MN/WEAKER PRES GRADIENT ARRIVE...A STRONGER W TO NW WIND WILL REDEVELOP LATER TONIGHT AS THE LO MOVES TO THE E ACROSS LAKE SUP...WITH MORE GALE FORCE WINDS OVER MAINLY THE W AND NCENTRAL AT TIMES INTO WED MORNING WHEN THE ARRIVAL OF COLDER AIR AS WELL WILL RESULT IN ENHANCED MIXING. THE APPROACH OF A HI PRES RIDGE AND WEAKER PRES GRADIENT WILL RESULT IN DIMINISHING WINDS BY WED AFTERNOON. HIGH PRESSURE RIDGE OVER THE AREA ON WED NIGHT WILL LEAD TO DIMINISHING WINDS AS THEY BACK TO THE NE. EXPECT WINDS TO STAY BELOW 20KTS FOR MUCH OF THE PERIOD AS A SERIES OF WEAK DISTURBANCES AND HIGH PRESSURE RIDGES MOVE ACROSS THE AREA THROUGH THE WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 AM EDT THIS MORNING FOR LSZ266. GALE WARNING FROM 5 AM TO 11 AM EDT THIS MORNING FOR LSZ244-245- 264. GALE WARNING UNTIL 5 AM EDT /4 AM CDT/ EARLY THIS MORNING FOR LSZ241-242-263. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...KC SHORT TERM...KC LONG TERM...SRF AVIATION...VOSS MARINE...KC/SRF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
207 AM EDT WED MAR 28 2012 .SYNOPSIS... A LOW PRESSURE SYSTEM MOVING THROUGH THE UPPER GREAT LAKES AND SOUTHERN CANADA WILL SWING A WARM FRONT THROUGH THE REGION WEDNESDAY MORNING...FOLLOWED BY A COLD FRONT IN THE AFTERNOON. THESE FRONTS WILL BRING SOME RAIN SHOWERS AND POSSIBLE THUNDER TO THE AREA WEDNESDAY. SCATTERED RAIN OR SNOW SHOWERS WILL BE POSSIBLE ACROSS CENTRAL NEW YORK ON WEDNESDAY NIGHT...WITH SLOWLY IMPROVING CONDITIONS EXPECTED ON THURSDAY. HIGH PRESSURE WILL BUILD IN WITH FAIR SKIES ON THURSDAY NIGHT. && .NEAR TERM /THROUGH TODAY/... .1250 AM UPDATE... QUICK UPDATED DESPERATELY NEEDED TO ACCOUNT FOR RISING TEMPS ACROSS THE WESTERN CWA AS REGION BECOMES ENVELOPED IN A WELL- ESTABLISHED WARM AIR ADVECTION REGIME. UNFORTUNATELY THERE IS NO MODEL GUIDANCE THAT SEEMS TO BE HANDLING THIS NON-DIURNAL TEMP TREND WELL SO QUITE A BIT OF MANUAL GRID MANIPULATION WAS NEEDED. IN ANY EVENT FURTHER TO OUR WEST...ANOTHER WARM FRONT IS DRAPED ACROSS THE UPPER OHIO VLY WHICH WILL BE APPROACHING THE AREA AFTER SUNRISE. MODELS CONTINUE TO SUGGEST SHWRS AND POSSIBLY EVEN AN ELEVATED THUNDERSTORM OR TWO ACCOMPANYING ITS PASSAGE AS ELEVATED CAPE VALUES QUICKLY APPROACH 500 J/KG ACROSS A GOOD CHUNK OF THE CWA. THIS WILL BE THE FIRST OF TWO ROUNDS OF RAIN/POSSIBLE THUNDER AS THE OCCLUDED TRIPLE POINT PASSES THROUGH THE AREA DURING THE AFTERNOON. WILL TACKLE THOSE DETAILS MORE THOROUGHLY WITH NEXT UPDATE. .PREVIOUS NEAR TERM UPDATES... 1030 PM UPDATE...FORECAST UPDATED TO INCREASE POPS WEDNESDAY MORNING...AND EVEN INCLUDE MENTION OF THUNDER. WE REMAIN VERY DRY AT THE LOW LEVELS...BUT THE STRENGTH OF THE WARM AIR ADVECTION WITH THE INCOMING SYSTEM MUST BE RESPECTED. IN FACT...DESPITE 35 DEGREE DEW POINT DEPRESSION FROM AN OBS SITE ON BRUCE PENINSULA AT THE SURFACE...ALOFT THERE IS ENOUGH MOISTURE AND EVEN INSTABILITY FOR A CLUSTER OF THUNDERSTORMS THAT HAS MANAGED TO DEVELOP. SURFACE-BASED LIFTED INDICES IN OUR SOUNDINGS 12Z-15Z OF COURSE ARE VERY POSITIVE. BUT A CLOSER LOOK AT THE LATEST SOUNDINGS REVEAL THAT ABOVE THE VERY STABLE NEAR SURFACE LAYER...THERE IS ACTUALLY A FAIR AMOUNT OF INSTABILITY. KELM NAM SOUNDING SEEN VIA BUFKIT FOR EXAMPLE MANAGES A FEW HUNDRED J/KG ELEVATED CAPE...AND PRECIPITABLE WATER CLIMBS ABOVE AN INCH. THE RAPID UPDATE HIGH RESOLUTION MODELS SUCH AS THE HRRR AND ARW ARE ALSO CATCHING ON TO THIS QUICKLY EVOLVING TREND...THAT SHOWERS AND EVEN THUNDER ARE BECOMING MORE PROBABLE IN THE MORNING. BRIEF WARM SECTOR THEN COMES IN BEHIND THE MORNING BATCH...ONLY FOR COLD FRONT TO THEN PASS THROUGH THE AREA FOR ADDITIONAL CHANCE OF SHOWERS AND THUNDER. WELL UPSTREAM...THUNDERSTORMS IN ILLINOIS ARE GIVING US A HINT OF THIS POTENTIAL. AS CAN BE EXPECTED WITH THE RADIATIONAL COOLING SITUATION UP TO NOW THIS EVENING...TEMPERATURES HAVE NEEDED TWEAKING TO KEEP UP WITH CURRENT CONDITIONS AND TRENDS. THICKENING HIGH CLOUDS AND INCREASING WARM AIR ADVECTION WILL ALLOW LOWS TO OCCUR BY AROUND MIDNIGHT OR SO...WITH HIGH CLOUDS AND WARM AIR ADVECTION HELPING TEMPERATURES TURN THE CORNER TO RISE FOR THE REMAINDER OF THE NIGHT. IF SHOWERS MOVE IN FAST ENOUGH...A COUPLE PLACES IN MOHAWK VALLEY...PARTICULARLY NORTHERN ONEIDA COUNTY COULD A LIGHT FREEZING RAIN THAT QUICKLY SWITCHES OVER TO PLAIN RAIN. HOWEVER...THIS IS NOT CONSIDERED VERY LIKELY AT THIS TIME...WITH MORE PROBABLE OUTCOME BEING TEMPERATURES BREAKING ABOVE FREEZING BEFORE OR JUST AS SHOWERS ARRIVE. BIG GRADIENT IN TEMPERATURES WEDNESDAY...WITH SURGE OF WARM AIR CAPTURING MOST OF THE AREA...YET TRIPLE POINT PASSING CLOSE TO THE NORTHEASTERN ZONES AND ALSO STABLE LOW LEVEL AIR BEING PERHAPS A BIT HARDER TO SCOUR OUT. PARTIAL SUNSHINE BETWEEN BATCHES OF SHOWERS/THUNDER...WILL ALLOW TEMPERATURES IN WARM SECTOR FOR MOST OF THE AREA TO CLIMB INTO THE UPPER 50S TO MID 60S...YET CLOSER TO 50 IN THE MOHAWK VALLEY NORTHWARD. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... 2NDRY SURGE OF COOLER AIR WORKS SOUTH ON WED NGT...AS S/WV MOVS BY TO THE N. MDLS SHOW MOIST NW FLOW...SO CHC POPS FOR -SHRA/-SHSN OVRNGT. SLOW IMPROVEMENT ON THU AS HIGH PRES TRIES TO BUILD IN BUT GUSTY NW WINDS SHUD PERSIST DURING THE DAY. WENT BELOW MOS GUIDANCE ON THU AS MOS MAXES WERE NOT SUPPORTED BY MDL 925 MB TEMPS...WHICH INFERRED MAXES THE L/M 40S. MAINLY SKC ON THU NGT AS SFC RDG AXIS MOVS INTO THE AREA. ON FRI LEANED TWDS THE 12Z GFS/00Z EURO...AND ONLY MENTIONED A SLGT CHC OF -SHRA ACRS FAR SW SXNS OF THE CWA LATE IN THE DAY. OTRW...IT APPEARS THAT THERE WILL BE PLENTY OF MID AND HI CLD SPREADING ACRS CNTRL AND SRN SXNS ON FRI. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... 440 PM UPDATE...LONG TERM PATTERN IS SOMEWHAT BUSY WITH QUICK SUCCESSION OF MID SCALE UPPER RIDGES AND WAVES. YET BECAUSE THESE UPPER FEATURES ARE NOT VERY BIG...THE FORECAST IS PRONE TO MODEL- TO-MODEL AND RUN-TO-RUN INCONSISTENCIES ON TIMING FOR EACH OF THEM. ALSO...WITH THE QUICK TIMING BETWEEN FEATURES...MOISTURE AVAILABILITY COULD BE AND ISSUE. THUS I DID NOT STRAY MUCH FROM HPC GUIDANCE...WHICH ITSELF WAS FAIRLY NON-COMMITTAL WITH SLIGHT TO LOW CHANCE POPS. ON A LARGER SCALE THOUGH...GFS/ECMWF AT LEAST HAVE COME INTO AGREEMENT ON NEAR NORMAL 500MB HEIGHTS EARLY IN THE WEEKEND...TRANSITIONING TO BRIEF PERIOD OF ABOVE NORMAL HEADING INTO MONDAY/TUESDAY. OUR FORECAST THUS ALSO TRENDS FROM NEAR NORMAL EARLY IN THE PERIOD...TO ROUGHLY 10 DEGREES ABOVE CLIMATOLOGY BY MONDAY/TUESDAY. ONE OTHER NOTE...NEW 12Z ECMWF HAS A COASTAL SURFACE LOW MOVING UP FROM THE MID-ATLANTIC TO OFFSHORE THE NORTHEAST...WITH THE BACK PART OF ITS PRECIPITATION SHIELD ALONG WITH A MORE AMPLIFIED UPPER WAVE OVER OUR REGION ON SUNDAY. THIS IS A SIGNIFICANT DEPARTURE FROM THE 00Z ECMWF...AND IS STARKLY DIFFERENT FROM THE 12Z GFS...SO NOT PUTTING TOO MUCH STOCK INTO THAT SCENARIO AT THIS TIME. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... 06Z UPDATE... VFR SHOULD PREVAIL THE MAJORITY OF THE TAF PD. THE BEST CHC FOR RESTRICTIVE CONDS WILL COME LTR TNT (STARTING IN THE 04-06Z THU TIME FRAME)...WHEN LWR CIGS/-SHRA SHOULD DEVELOP...INITIALLY ACRS THE CNY TERMINALS. IN THE NEAR-TERM (THROUGH ABT 12Z)...THE PRIMARY ISSUE WILL BE LLWS...AS A SHARP SFC-BASED INVERSION EXISTS...WITH MUCH STGR WINDS JUST OFF THE DECK (AOA 1500-2000 FEET AGL). SCTD -SHRA SHOULD MOVE ACRS THE NRN TERMINALS (KSYR/KRME/KITH) IN THE 12-15Z TIME FRAME...BUT UNRESTRICTED CIGS/VSBYS ARE ANTICIPATED WITH THIS ACTIVITY. THEN...THIS AFTN...ANOTHER ROUND OF ISOLD/SCTD -SHRA ARE EXPECTED. AGAIN...THOUGH...UNRESTRICTED CONDS ARE GENERALLY FORESEEN...AND COVERAGE IS EVEN A BIT MORE QUESTIONABLE...SO WE`VE LEFT OUT OF THE FORECAST AT THIS JUNCTURE. SFC WINDS SHOULD TURN SW AND BECOME FAIRLY GUSTY IN THE LATE MRNG/EARLY AFTN PD. BEHIND THE COLD FRNT LATER IN THE DAY AND THIS EVE...GUSTY NW WINDS ARE EXPECTED (UP TO 25-30 KT). .OUTLOOK... THU MRNG...CHC MVFR IN -SHRA...MIXED WITH -SHSN AT TIMES...SPCLY KBGM/KITH. THU AFTN TO FRI...MAINLY VFR. FRI NGT INTO SAT...CHC OF RESTRICTIONS IN LWR CIGS/-RA...PSBLY MIXED WITH -SN ON THE HILLS AT KBGM/KITH BY EARLY SAT. SAT AFTN AND NGT...MAINLY VFR. SUN...CHC MVFR IN -SHRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...CMG/MDP SHORT TERM... LONG TERM...MDP AVIATION...MLJ/TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
100 AM EDT WED MAR 28 2012 .SYNOPSIS... A LOW PRESSURE SYSTEM MOVING THROUGH THE UPPER GREAT LAKES AND SOUTHERN CANADA WILL SWING A WARM FRONT THROUGH THE REGION WEDNESDAY MORNING...FOLLOWED BY A COLD FRONT IN THE AFTERNOON. THESE FRONTS WILL BRING SOME RAIN SHOWERS AND POSSIBLE THUNDER TO THE AREA WEDNESDAY. SCATTERED RAIN OR SNOW SHOWERS WILL BE POSSIBLE ACROSS CENTRAL NEW YORK ON WEDNESDAY NIGHT...WITH SLOWLY IMPROVING CONDITIONS EXPECTED ON THURSDAY. HIGH PRESSURE WILL BUILD IN WITH FAIR SKIES ON THURSDAY NIGHT. && .NEAR TERM /THROUGH TODAY/... .1250 AM UPDATE... QUICK UPDATED DESPERATELY NEEDED TO ACCOUNT FOR RISING TEMPS ACROSS THE WESTERN CWA AS REGION BECOMES ENVELOPED IN A WELL- ESTABLISHED WARM AIR ADVECTION REGIME. UNFORTUNATELY THERE IS NO MODEL GUIDANCE THAT SEEMS TO BE HANDLING THIS NON-DIURNAL TEMP TREND WELL SO QUITE A BIT OF MANUAL GRID MANIPULATION WAS NEEDED. IN ANY EVENT FURTHER TO OUR WEST...ANOTHER WARM FRONT IS DRAPED ACROSS THE UPPER OHIO VLY WHICH WILL BE APPROACHING THE AREA AFTER SUNRISE. MODELS CONTINUE TO SUGGEST SHWRS AND POSSIBLY EVEN AN ELEVATED THUNDERSTORM OR TWO ACCOMPANYING ITS PASSAGE AS ELEVATED CAPE VALUES QUICKLY APPROACH 500 J/KG ACROSS A GOOD CHUNK OF THE CWA. THIS WILL BE THE FIRST OF TWO ROUNDS OF RAIN/POSSIBLE THUNDER AS THE OCCLUDED TRIPLE POINT PASSES THROUGH THE AREA DURING THE AFTERNOON. WILL TACKLE THOSE DETAILS MORE THOROUGHLY WITH NEXT UPDATE. .PREVIOUS NEAR TERM UPDATES... 1030 PM UPDATE...FORECAST UPDATED TO INCREASE POPS WEDNESDAY MORNING...AND EVEN INCLUDE MENTION OF THUNDER. WE REMAIN VERY DRY AT THE LOW LEVELS...BUT THE STRENGTH OF THE WARM AIR ADVECTION WITH THE INCOMING SYSTEM MUST BE RESPECTED. IN FACT...DESPITE 35 DEGREE DEWPOINT DEPRESSION FROM AN OBS SITE ON BRUCE PENINSULA AT THE SURFACE...ALOFT THERE IS ENOUGH MOISTURE AND EVEN INSTABILITY FOR A CLUSTER OF THUNDERSTORMS THAT HAS MANAGED TO DEVELOP. SURFACE-BASED LIFTED INDICES IN OUR SOUNDINGS 12Z-15Z OF COURSE ARE VERY POSITIVE. BUT A CLOSER LOOK AT THE LATEST SOUNDINGS REVEAL THAT ABOVE THE VERY STABLE NEAR SURFACE LAYER...THERE IS ACTUALLY A FAIR AMOUNT OF INSTABILITY. KELM NAM SOUNDING SEEN VIA BUFKIT FOR EXAMPLE MANAGES A FEW HUNDRED J/KG ELEVATED CAPE...AND PRECIPITABLE WATER CLIMBS ABOVE AN INCH. THE RAPID UPDATE HIGH RESOLUTION MODELS SUCH AS THE HRRR AND ARW ARE ALSO CATCHING ON TO THIS QUICKLY EVOLVING TREND...THAT SHOWERS AND EVEN THUNDER ARE BECOMING MORE PROBABLE IN THE MORNING. BRIEF WARM SECTOR THEN COMES IN BEHIND THE MORNING BATCH...ONLY FOR COLD FRONT TO THEN PASS THROUGH THE AREA FOR ADDITIONAL CHANCE OF SHOWERS AND THUNDER. WELL UPSTREAM...THUNDERSTORMS IN ILLINOIS ARE GIVING US A HINT OF THIS POTENTIAL. AS CAN BE EXPECTED WITH THE RADIATIONAL COOLING SITUATION UP TO NOW THIS EVENING...TEMPERATURES HAVE NEEDED TWEAKING TO KEEP UP WITH CURRENT CONDITIONS AND TRENDS. THICKENING HIGH CLOUDS AND INCREASING WARM AIR ADVECTION WILL ALLOW LOWS TO OCCUR BY AROUND MIDNIGHT OR SO...WITH HIGH CLOUDS AND WARM AIR ADVECTION HELPING TEMPERATURES TURN THE CORNER TO RISE FOR THE REMAINDER OF THE NIGHT. IF SHOWERS MOVE IN FAST ENOUGH...A COUPLE PLACES IN MOHAWK VALLEY...PARTICULARLY NORTHERN ONEIDA COUNTY COULD A LIGHT FREEZING RAIN THAT QUICKLY SWITCHES OVER TO PLAIN RAIN. HOWEVER...THIS IS NOT CONSIDERED VERY LIKELY AT THIS TIME...WITH MORE PROBABLE OUTCOMING BEING TEMPERATURES BREAKING ABOVE FREEZING BEFORE OR JUST AS SHOWERS ARRIVE. BIG GRADIENT IN TEMPERATURES WEDNESDAY...WITH SURGE OF WARM AIR CAPTURING MOST OF THE AREA...YET TRIPLE POINT PASSING CLOSE TO THE NORTHEASTERN ZONES AND ALSO STABLE LOW LEVEL AIR BEING PERHAPS A BIT HARDER TO SCOUR OUT. PARTIAL SUNSHINE BETWEEN BATCHES OF SHOWERS/THUNDER...WILL ALLOW TEMPERATURES IN WARM SECTOR FOR MOST OF THE AREA TO CLIMB INTO THE UPPER 50S TO MID 60S...YET CLOSER TO 50 IN THE MOHAWK VALLEY NORTHWARD. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... 2NDRY SURGE OF COOLER AIR WORKS SOUTH ON WED NGT...AS S/WV MOVS BY TO THE N. MDLS SHOW MOIST NW FLOW...SO CHC POPS FOR -SHRA/-SHSN OVRNGT. SLOW IMPROVMENT ON THU AS HIGH PRES TRIES TO BUILD IN BUT GUSTY NW WINDS SHUD PERSIST DURING THE DAY. WENT BELOW MOS GUIDANCE ON THU AS MOS MAXES WERE NOT SUPPORTED BY MDL 925 MB TEMPS...WHICH INFERRED MAXES THE L/M 40S. MAINLY SKC ON THU NGT AS SFC RDG AXIS MOVS INTO THE AREA. ON FRI LEANED TWDS THE 12Z GFS/00Z EURO...AND ONLY MENTIONED A SLGT CHC OF -SHRA ACRS FAR SW SXNS OF THE CWA LATE IN THE DAY. OTRW...IT APPEARS THAT THERE WILL BE PLENTY OF MID AND HI CLD SPREADING ACRS CNTRL AND SRN SXNS ON FRI. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... 440 PM UPDATE...LONG TERM PATTERN IS SOMEWHAT BUSY WITH QUICK SUCCESSION OF MID SCALE UPPER RIDGES AND WAVES. YET BECAUSE THESE UPPER FEATURES ARE NOT VERY BIG...THE FORECAST IS PRONE TO MODEL- TO-MODEL AND RUN-TO-RUN INCONSISTENCIES ON TIMING FOR EACH OF THEM. ALSO...WITH THE QUICK TIMING BETWEEN FEATURES...MOISTURE AVAILABILITY COULD BE AND ISSUE. THUS I DID NOT STRAY MUCH FROM HPC GUIDANCE...WHICH ITSELF WAS FAIRLY NON-COMMITTAL WITH SLIGHT TO LOW CHANCE POPS. ON A LARGER SCALE THOUGH...GFS/ECMWF AT LEAST HAVE COME INTO AGREEMENT ON NEAR NORMAL 500MB HEIGHTS EARLY IN THE WEEKEND...TRANSITIONING TO BRIEF PERIOD OF ABOVE NORMAL HEADING INTO MONDAY/TUESDAY. OUR FORECAST THUS ALSO TRENDS FROM NEAR NORMAL EARLY IN THE PERIOD...TO ROUGHLY 10 DEGREES ABOVE CLIMATOLOGY BY MONDAY/TUESDAY. ONE OTHER NOTE...NEW 12Z ECMWF HAS A COASTAL SURFACE LOW MOVING UP FROM THE MIDATLANTIC TO OFFSHORE THE NORTHEAST...WITH THE BACK PART OF ITS PRECIPITATION SHIELD ALONG WITH A MORE AMPLIFIED UPPER WAVE OVER OUR REGION ON SUNDAY. THIS IS A SIGNIFICANT DEPARTURE FROM THE 00Z ECMWF...AND IS STARKLY DIFFERENT FROM THE 12Z GFS...SO NOT PUTTING TOO MUCH STOCK INTO THAT SCENARIO AT THIS TIME. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... 730 PM UPDATE... IN GENERAL VFR CONDITIONS EXPECTED THROUGH TAF PERIOD. SFC LOW PRES MOVING THROUGH THE UPPER GREAT LAKES INTO SOUTHERN ONTARIO WILL BRING A WARM FRONT NEAR THE REGION LATE WED MORNING. MID/HIGH LEVEL CLOUDS WILL INCREASE OVERNIGHT WITH CIGS DROPPING TO 5K FT AROUND 11Z IN NY. SYSTEM LACKS MOISTURE AND IS MOVING INTO A VERY DRY AIRMASS THEREFORE ONLY INCLUDED PROB30 FOR MVFR RAIN SHOWERS AT KRME/KSYR BETWEEN 14Z TO 18Z. CIGS AT KRME COULD FALL TO MVFR WITH ANY MIDDAY SHOWERS. FOR THE AFTN AT KRME/KSYR PUT PREDOMINANT SHOWERS BUT CONFIDENCE NOT HIGH. NOT EXPECTING MVFR WITH THE SHOWERS. A BETTER CHANCE FOR SHOWERS EARLY EVENING AFTER 00Z. LIGHT AND VARIABLE WINDS BECOMING E/SE OVERNIGHT AT 5-10 KNOTS. LOW LEVEL WINDS SHEAR IS LIKELY LATE TONIGHT DUE TO SHARP INVERSION WITH STRONG SPEED/DIRECTIONAL SHEAR. WINDS AT 2K FT BY 06Z WILL BE 22035KT. SFC WINDS BECOMING S/SW AFTER SUNRISE AROUND 10 KNOTS. WINDS SHIFT TO WEST IN THE AFTN AT 12G20KTS. .OUTLOOK... WED NIGHT TO THU...CHC MVFR IN -SHRA...MIXED WITH -SHSN AT TIMES LATE WEDNESDAY NIGHT AND THURSDAY MORNING. THURSDAY AFTN TO FRIDAY NIGHT...VFR. SAT...CHC MVFR IN -SHRA...MOSTLY FOR KAVP. SAT NGT...VFR. SUNDAY...CHC MVFR IN -SHRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...CMG/MDP SHORT TERM... LONG TERM...MDP AVIATION...TAC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
356 AM EDT WED MAR 28 2012 .SYNOPSIS... A LOW PRESSURE SYSTEM WILL MOVE EAST THROUGH THE UPPER GREAT LAKES TODAY...PUSHING A COLD FRONT SOUTH ACROSS THE AREA BY TONIGHT. HIGH PRESSURE WILL BUILD SOUTH OUT OF CANADA ON THURSDAY WITH COLDER TEMPERATURES AND FROST POSSIBLE AGAIN ON THURSDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM WILL TRACK EAST ACROSS THE AREA ON FRIDAY BRINGING ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A LOW PRESSURE SYSTEM WILL MOVE EAST ACROSS THE UPPER GREAT LAKES TODAY...WITH WARM ADVECTION OCCURRING EARLY THIS MORNING... FOLLOWED BY A WEAK COLD FRONT THAT WILL GRADUALLY SINK SOUTH LATE THIS AFTERNOON. MOISTURE ADVECTION IS OCCURRING IN THE WARM SECTOR ALTHOUGH UPSTREAM COVERAGE OF SHOWERS AND THUNDERSTORMS EARLY THIS MORNING HAS BEEN UNIMPRESSIVE ACROSS INDIANA. 06Z SPC RUC ANALYSIS SHOWS BETTER MOISTURE LOCATED IN CENTRAL ILLINOIS WHERE CONVECTION CONTINUES TO FIRE IMMEDIATELY AHEAD OF THE COLD FRONT. ALTHOUGH MOISTURE TRANSPORT WILL CONTINUE INTO NORTHERN OHIO THIS MORNING...WONDERING IF THE BETTER MOISTURE IS GETTING PINCHED OFF AS THE FLOW ALOFT BECOMES INCREASINGLY ORIENTED PARALLEL TO THE FRONT. IT IS STILL POSSIBLE THAT WE WILL SEE AN UPTICK IN SHOWERS AS THE FRONT SLIDES EAST ACROSS THE AREA THROUGH MID-MORNING WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS STILL POSSIBLE. CLOUDS WILL CLEAR OUT BY AFTERNOON AS THE DRY SLOT WORKS INTO THE AREA FROM THE WEST. WE ARE EXPECTED TO MIX TO AROUND 850MB THIS AFTERNOON UNDER MOSTLY SUNNY SKIES ALLOWING TEMPERATURES TO CLIMB SEVERAL DEGREES WARMER THAN YESTERDAY...PEAKING IN THE LOW TO MID 60S BY EARLY AFTERNOON. WINDY CONDITIONS ARE ALSO EXPECTED WITH WESTERLY WINDS NEAR 20 MPH AND GUSTS TO 35 MPH. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... COLD ADVECTION WILL CONTINUE INTO TONIGHT WITH A POCKET OF COLD AIR AT 850MB (-2 TO -4C) SETTLING SOUTHEAST OUT OF MICHIGAN TOWARDS NW PA. THE COMBINATION OF INCREASING LOW LEVEL MOISTURE AND MOISTURE OFF LAKE ERIE WILL RESULT IN PARTLY TO MOSTLY CLOUDY SKIES. INSTABILITY OVER THE LAKE WILL BE MARGINAL FOR PURE LAKE EFFECT RAIN SHOWERS...BUT ENOUGH LOW LEVEL MOISTURE SHOULD BE PRESENT TO SEE SCATTERED LIGHT RAIN SHOWERS OFF THE LAKE OVER THE HIGHER TERRAIN OF NE OH/NW PA. THE INCREASING CLOUD COVER AND BREEZY NORTHWESTERLY WINDS WILL HELP TO PREVENT FROST TONIGHT...WITH LOWS GENERALLY BOTTOMING OUT IN THE MID 30S. CLOUDS WILL SCATTER OUT FROM WEST TO EAST ON THURSDAY AS HIGH PRESSURE BUILDS SOUTHEAST OUT OF CANADA. OUR PROXIMITY TO THE SOUTHERN FRINGE OF THE SURFACE HIGH ON THURSDAY NIGHT WITH MOSTLY CLEAR SKIES WILL BE MORE FAVORABLE FOR FROST WITH LOWS FORECAST TO DROP INTO THE MID 20S EAST TO MID 30S WEST. THERE WILL BE SOME HIGH CLOUDS AROUND ON THURSDAY NIGHT BUT FROST/FREEZING CONDITIONS WILL BE POSSIBLE AGAIN...MAINLY IN EASTERN PORTIONS OF THE FORECAST AREA. SHORTWAVE ENERGY APPROACHING THE WEST COAST WILL MAKE ITS WAY EAST ACROSS THE PLAINS TOWARDS THE SOUTHERN GREAT LAKES BY FRIDAY. LIFT WILL RAMP UP AND BECOME STRONG ALONG THE 925-850MB FRONT AS THE SURFACE LOW TRACKS EAST INTO INDIANA ON FRIDAY. MODELS HAVE BEEN TRENDING IN THIS DIRECTION FOR A COUPLE DAYS AND HAVE RAISED POPS FOR FRIDAY AFTERNOON. ALTHOUGH THE SURFACE WARM FRONT MAY STRUGGLE TO LIFT NORTH OF A DAYTON TO MARION LINE...ENOUGH ELEVATED INSTABILITY WILL BE IN PLACE FOR THUNDERSTORMS AND COULD END UP WITH A GOOD STEADY RAIN. HIGH PRESSURE WILL BUILD SOUTH OVER THE AREA BEHIND THE DEPARTING SURFACE LOW ON SATURDAY WITH SHOWERS ENDING FROM NORTH TO SOUTH DURING THE MORNING. && .LONG TERM /SUNDAY THROUGH TUESDAY/... FOLLOWED GFS TIMING FOR MOST OF THE EXTENDED. SUNDAY AND MONDAY LOOK MILD WITH TEMPS INTO THE 70S DURING THE AFTERNOONS AND NIGHTTIME LOWS 55 TO 60 SUNDAY NIGHT. DURING MONDAY A COLD FRONT WILL MOVES THROUGH THE AREA FOLLOWED BY ANOTHER COLD FRONT MONDAY NIGHT. BY TUESDAY MORNING EXPECT LOWS TO DROP THROUGH THE 40S. HIGHS POST FRONT TUESDAY 55 TO 60 LOOK REASONABLE. AS FOR POPS WILL KEEP FORECAST DRY SUNDAY AND THEN BRING IN A CHANCE POP FOR MONDAY THROUGH TUESDAY WITH THE FRONT. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... VFR CONDITIONS ACROSS NRN OHIO AND NWRN PA AT 05Z. A WARM FRONT EXTENDING NORTH/SOUTH ACROSS EASTERN OHIO WILL CONTINUE EAST. TO THE WEST...A COLD FRONT IS APPROACHING ILLINOIS WHILE A SURFACE TROF AHEAD OF THE FRONT IS RESPONSIBLE FOR SHOWERS AND THUNDERSTORMS FROM VPZ VCNTY SW TO PIA VCNTY. THESE SHOWERS AND THUNDERSTORMS WILL CONTINUE MOVING EAST AND SHOULD REACH INTO WESTERN/NWRN OHIO AROUND 10-12Z BASED ON CURRENT TIMING. NOT CONFIDENT ABOUT THUNDER SUSTAINING ACROSS THE ENTIRE AREA DURING THE MORNING SO EAST OF MFD BACKED OFF TO JUST SHOWERS. EXPECT A BRIEF PERIOD OF SHOWERS AS THE TROF MOVES THROUGH AND THEN CLOUDS SHOULD BREAK UP AGAIN FOR MUCH OF THE LATE MORNING AND AFTERNOON ACROSS THE AREA. WINDS HOWEVER WILL CONTINUE TO BE GUSTY WITH WINDS FROM THE SSW GUSTING INTO THE 20-25 KNOT RANGE EXCEPT 30 KNOTS AT KERI OVERNIGHT AHEAD OF THE FRONT. POST FRONT WINDS WILL TURN WEST-NORTHWEST AND GUST TO THE 30 KNOT RANGE THROUGH MUCH OF THE AFTERNOON BEFORE DROPPING BACK THIS EVENING. LATE AFTERNOON/EARLY EVENING EXPECT LOW VFR TO MVFR CIGS TO DROP ACROSS THE AREA FROM THE NORTH. .OUTLOOK...NON VFR LIKELY TONIGHT (WED NGT) INTO THURSDAY AND AGAIN FRIDAY NIGHT INTO SATURDAY. && .MARINE... LOW PRESSURE JUST NORTH OF THE GREAT LAKES WILL MOVE EAST TO NEW ENGLAND BY THIS EVENING DRAGGING A COLD FRONT ACROSS LAKE ERIE THIS MORNING. WILL MOVE SMALL CRAFT UP TO ISSUE TIME. WINDS ON THE LAKE AWAY FROM SHORE SHOULD BE LOWER THAN NEAR THE SHORELINE GIVEN THE COLD WATER HOWEVER WINDS NEAR THE SHORELINE ARE CLOSE TO CRITERIA. WOULD RATHER BE CAUTIOUS GIVEN THE DANGER OF THE COLD WATER. WINDS AND WAVES WILL BE INCREASING THROUGH THE MORNING ESPECIALLY BEHIND THE COLD FRONT. EXPECT WINDS IN THE 15 TO 25 KNOT RANGE WITH WAVES APPROACHING 4 TO 6 FEET. WINDS/WAVES WILL DROP OFF TONIGHT. HIGH PRESSURE WILL NOSE INTO THE AREA FROM THE NORTH FOR MID WEEK. FRIDAY THE NAM MOVES A LOW ACROSS OHIO. THIS SHOULD BRING SHOWERS AND THUNDERSTORMS TO THE LAKE WITH EAST WINDS TURNING NORTHEAST AT 15 TO 20 KNOTS OR SO DURING THE DAY. FRIDAY NIGHT THE WINDS WILL TURN NORTH/NORTHWEST BEHIND THE LOW. WILL LIKELY NEED SMALL CRAFT HEADLINES WITH THIS SYSTEM. SATURDAY ANOTHER HIGH WILL BUILD ACROSS THE LAKE. SUNDAY THE HIGH WILL MOVE EAST ALONG THE MID ATLANTIC COAST WITH LOW PRESSURE IN THE DAKOTAS. THIS SHOULD BRING MILD AIR TO THE REGION AND SOUTHWEST TO WEST WINDS 10 TO 20 KNOTS TO THE LAKE. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ142>149. && $$ SYNOPSIS...KEC NEAR TERM...KEC SHORT TERM...KEC LONG TERM...TK AVIATION...TK MARINE...TK
AREA FORECAST DISCUSSION
NWS NORMAN OK
1213 AM CDT WED MAR 28 2012 .AVIATION...ANTICIPATE DEVELOPMENT OF MVFR CEILINGS MOST TAF SITES IN THE PERIOD 2809/2815 UTC. DID NOT GO AS PESSIMISTIC AS THE IFR CEILINGS IN THE NAM GUIDANCE...BUT SOME IFR CONDITIONS WILL BE POSSIBLE. STEADY SOUTH WINDS WILL CONTINUE THROUGH THE 24 HOUR PERIOD...WITH STRONGER SUSTAINED SPEEDS BEGINNING MIDDAY THURSDAY. NO PRECIPITATION EXPECTED. && .PREV DISCUSSION... /ISSUED 937 PM CDT TUE MAR 27 2012/ DISCUSSION... ADJUSTMENTS WERE MADE TO SKY COVER FOR LATE TONIGHT. THE RUC AND GFS AND HRRR ARE SIMILAR IN DEVELOPING LOW CLOUDS IN WESTERN OKLAHOMA AND/OR ADVECTING THEM ACROSS SOUTHERN OKLAHOMA FROM THE SOUTH. OTHERWISE LITTLE CHANGES ARE NECESSARY FOR THE OVERNIGHT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 58 82 60 81 / 10 10 20 20 HOBART OK 59 82 59 80 / 20 20 20 20 WICHITA FALLS TX 60 84 60 83 / 10 20 20 30 GAGE OK 54 85 56 85 / 20 20 30 20 PONCA CITY OK 58 83 61 84 / 20 20 30 20 DURANT OK 59 81 60 77 / 10 10 10 20 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 09/22/22
AREA FORECAST DISCUSSION
NWS TULSA OK
1137 PM CDT TUE MAR 27 2012 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. SHOWERS OVER CENTRAL OK HAVE LONG SINCE DISSIPATED AND ONLY PASSING MID CLOUDS REMAIN. GRADUAL INCREASE IN MOISTURE WILL LEAD TO CEILINGS IN THE 5-6KFT RANGE BY WEDNESDAY MORNING. ANY THUNDERSTORMS THAT DEVELOP ALONG THE FRONTAL BOUNDARY ACROSS KANSAS WILL LIKELY REMAIN TO OUR NORTH. && .PREV DISCUSSION... /ISSUED 728 PM CDT TUE MAR 27 2012/ DISCUSSION... THE LATEST DATA FROM THE NAM AND HRRR SUGGESTS THAT WE WILL REMAIN CAPPED THIS EVENING IN THE WARM SECTOR SOUTH OF THE STALLED FRONT OVER KS. THE 00Z OUN SOUNDING CONFIRMS THIS...WITH A STOUT EML FROM 600MB DOWN TO AROUND 800MB. SOME HIGH BASED SHOWERS AND A FEW LIGHTNING STRIKES OCCURRED EARLIER OVER CENTRAL OK ABOVE THE CAP AT THE TOP OF THE EML...BUT THAT ACTIVITY HAS SINCE DISSIPATED. ONE WOULD THINK THAT IF THERE IS ANY WARM ADV ACTIVITY TONIGHT IT WOULD BE NORTH OF THE FRONT OVER KS...THUS I HAVE REMOVED THUNDER MENTION FROM THE FORECAST TONIGHT. SOME SMALL TWEAKS WERE MADE TO THE LOWS TONIGHT AS WELL. UPDATED PRODUCTS HAVE BEEN SENT. LACY PREV DISCUSSION... /ISSUED 602 PM CDT TUE MAR 27 2012/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. UPPER LEVEL DISTURBANCE WILL MOVE FROM CENTRAL OK INTO NE OKLAHOMA THIS EVENING...HOWEVER SHOWERS ASSOCIATED WITH THIS SYSTEM APPEAR UNLIKELY TO HOLD TOGETHER MUCH LONGER. THUS A DRY FORECAST FOR THE EVENING WILL BE MAINTAINED WITH INCREASING MID CLOUDS. CEILINGS EVENTUALLY WILL LOWER BUT SHOULD REMAIN ABOVE VFR LEVELS THROUGHOUT THE PERIOD. ANY THUNDERSTORMS THAT DEVELOP ALONG A FRONTAL BOUNDARY IN KANSAS WILL REMAIN NORTH OF ALL TAF SITES AS WELL. PREV DISCUSSION... /ISSUED 407 PM CDT TUE MAR 27 2012/ DISCUSSION... FRONTAL BOUNDARY FROM NORTHWEST MISSOURI TO THE TEXAS PANHANDLE WILL NOT REACH NORTHEAST OK OVERNIGHT GIVEN SLIGHTLY SOUTH OF WEST UPPER FLOW. HOWEVER CONVECTION OUT AHEAD OF THAT FRONT..MAY REACH..THE NORTHERN TIER OF NORTHEAST OK COUNTIES. CHANCE POPS CARRIED ABOUT I-44 NORTH TO KANSAS BORDER. BEST CHANCE NEAR KANSAS. NORTHERN TIER OF ZONES REMAIN WITH LOW POPS WEDNESDAY WHERE INSTABILITY GREATEST AND INCREASING LOW LEVEL MOISTURE SUPPORTS HEALTHY THUNDER IF THUNDER DEVELOPS. CHANCE POPS CONTINUE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. A WAVE IN THE UPPER FLOW SHOULD ENHANCE PRECIP CHANCES FRIDAY AND FRIDAY NIGHT. KEPT POPS JUST BELOW LIKELY THRESHOLD FRIDAY. FIRST HALF OF WEEKEND LOOKS IFFY DEPENDING ON WAVE SPEED. ECMWF ABOUT STATE AHEAD OF LINGERING GFS. AS USUAL LEANED EUROPEAN. CONTINUED TO LEAN ECMWF THROUGH REMAINDER OF FORECAST. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...14
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1201 AM CDT WED MAR 28 2012 .AVIATION... MCS PROGRESSING ACROSS THE RIO GRANDE PLAINS IS EXPECTED TO DIE OUT BEFORE REACHING KSAT/KSSF. HOWEVER...MODELS HAVE HAD A HARD TIME WITH THE MCS THIS EVENING...AND MAY NEED TO SEND AN UPDATE BY ABOUT 08Z. OTHERWISE...MVFR STRATUS WILL DEVELOP OVERNIGHT...THOUGH CURRENTLY HAVE MUCH LOWER CONFIDENCE AS FAR AS TIMING DUE TO THE AFOREMENTIONED THUNDERSTORMS. HAVE KEPT A MIX OF FOG AND LOW STRATUS OVERNIGHT AND GRADUALLY RETURNING TO VFR BY ABOUT 18Z. && .PREV DISCUSSION... /ISSUED 916 PM CDT TUE MAR 27 2012/ UPDATE... MCS ENTERING THE FAR WESTERN VAL VERDE COUNTY...WITH THE LEADING EDGE OF STORMS HAVE SHOWN A SLIGHT WEAKENING TREND THE LAST HOUR. 00Z RUC AND NAM SHOW CONVECTION WEAKENING THRU 06Z...ALTHOUGH WILL KEEP LOW POPS IN ACROSS THE RIO GRANDE PLAINS OVER THE WESTERN 3RD OF THE CWA A FEW HOURS LONGER...SIMILAR TO LAST NIGHT. OTHERWISE ONGOING FORECAST IN GOOD SHAPE AND NO MAJOR CHANGES WILL BE NEEDED. PREV DISCUSSION... /ISSUED 635 PM CDT TUE MAR 27 2012/ AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE EVENING. THE COMPLEX OF THUNDERSTORMS ACROSS THE BIG BEND REGION IS MAKING SLOW S/SW-WRD PROGRESS THIS EVENING. LATEST RUC ANALYSIS SUGGESTS THAT THE TSRA WILL CONTINUE TO MOVE SW-WRD THIS EVENING...BUT SHEAR APART/DISSIPATE BEFORE REACHING KDRT. HAVE THEREFORE OPTED TO MENTION CB AROUND KDRT LATER TONIGHT...BUT CONFIDENCE IS TOO LOW TO WARRANT EXPLICIT MENTION OF TSRA AT THE TERMINAL. OTHERWISE...SHRA/TSRA EARLIER THIS AFTERNOON ACROSS THE RIO GRANDE PLAINS AND ADJACENT AREAS IS RAPIDLY TRENDING DOWNWARD AND SHOULD CONTINUE TO DO SO WITH THE LOSS OF DAYTIME HEATING. ANTICIPATE ANOTHER ROUND OF MVFR STRATUS AOB 2KFT TO SETTLE IN ALONG THE I-35 CORRIDOR BY ABOUT 06Z. CIGS WILL LOWER AND SPREAD WEST OVERNIGHT...WITH LIFR CIGS POSSIBLE AT KAUS/KSAT/KSSF IN THE NEAR-DAYBREAK HOURS. SIMILAR TO TODAY...CONDITIONS WILL BE SLOW TO IMPROVE...BUT VFR CONDITIONS WILL RETURN AROUND/AFTER 18Z. PREV DISCUSSION... /ISSUED 331 PM CDT TUE MAR 27 2012/ DISCUSSION... THE SOUTHERN PLAINS SITS UNDER THE BACKSIDE OF AN UPPER LEVEL RIDGE FROM 700-250MB THIS AFTERNOON. WE ARE BEGINNING TO SEE A SLOW SHIFT IN THE PATTERN. HEIGHTS HAVE FALLEN SLIGHTLY OVER THE PAST DAY. THIS COMBINED WITH STRONG HEATING OVER THE MOUNTAINS IN NORTHERN MEXICO IS ALLOWING THUNDERSTORMS TO FORM. SIMILAR TO LAST NIGHT EXPECT STORMS THROUGH THE EVENING...BUT QUESTION IS WHETHER THEY CAN MAKE ACROSS THE PLAINS INTO TX. ATMOSPHERE IS FAIRLY CAPPED OVER OUR CWA...SO HAVE ONLY SLIGHT CHANCE POPS OVER THE WESTERN THIRD OF THE AREA. ANY STORMS THAT DO MAKE IT ACROSS MAY BE STRONG WITH SMALL HAIL AND GUSTY WINDS. WED LOOKS VERY SIMILAR TO TODAY WITH PERHAPS A LITTLE BETTER CHANCE OF STORMS MAKING ACROSS NORTHERN MEXICO INTO TX. THU THE UPPER TROUGH WHICH IS OVER THE WEST COAST WILL APPROACH TX AND THIS WILL BRING A BETTER CHANCE FOR THUNDERSTORMS TO MORE OF THE AREA. AT THIS TIME MODEL SOUNDINGS SUGGEST STORMS WILL BE NOT BE PARTICULARLY STRONG WITH MODERATE INSTABILITY AND VERTICAL WIND SHEAR. THE UPPER TROUGH SHOULD CLEAR THE AREA BY FRI EVENING LEAVING DRY WEATHER FOR THE WEEKEND. ECMWF AND GFS ARE BOTH SHOWING A COLD FRONT EARLY NEXT WEEK...BUT DIFFER ON ITS STRENGTH. GFS IS STRONGER. HAVE TRENDED TOWARD THE WEAKER ECMWF AND INCREASED TEMPS FOR MON AND TUE. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 64 81 63 79 61 / 10 10 10 20 40 AUSTIN BERGSTROM INTL AIRPORT 63 81 61 79 60 / 10 10 10 20 40 NEW BRAUNFELS MUNI AIRPORT 64 80 62 77 60 / 10 10 10 20 40 BURNET MUNI AIRPORT 63 80 61 77 61 / 10 10 10 20 40 DEL RIO INTL AIRPORT 67 83 67 78 64 / 40 10 30 40 50 GEORGETOWN MUNI AIRPORT 62 78 61 77 60 / 10 10 10 20 40 HONDO MUNI AIRPORT 65 82 64 77 62 / 20 10 20 40 50 SAN MARCOS MUNI AIRPORT 63 80 62 78 60 / 10 10 10 20 40 LA GRANGE - FAYETTE REGIONAL 63 80 61 78 61 / 10 - 10 20 30 SAN ANTONIO INTL AIRPORT 66 81 64 77 63 / 10 10 10 30 50 STINSON MUNI AIRPORT 67 82 65 77 63 / 10 10 10 30 50 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...25 SYNOPTIC/GRIDS...01
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
356 AM CDT WED MAR 28 2012 .SHORT TERM... 356 AM CDT WED MAR 28 2012 FORECAST CONCERNS THIS PACKAGE...FROST POTENTIAL TONIGHT...RAIN CHANCES CENTERED ON THU NIGHT...TEMPERATURES. DATA ANALYSIS AT 06Z HAD A BROAD AREA OF LOW PRESSURE CENTERED JUST NORTH OF LK SUPERIOR. PRESSURE GRADIENT AROUND THIS LOW STILL EXTENDED ACROSS MN/WI/MUCH OF IA AND CONTINUED TO RELAX EARLY THIS MORNING. WINDS ACROSS MOST OF MN/WI REMAINED IN THE 10-20KT RANGE. CLOUDS IN THE CIRCULATION AROUND THE LOW COVERED CENTRAL/ NORTHERN MN AND WI NORTH OF HWY 29...WITH GENERALLY CLEAR SKIES ELSEWHERE ACROSS THE UPPER MIDWEST. TEMPS ACROSS THE REGION COOLING IN THE WEST/NORTHWEST FLOW BUT REMAINED WELL ABOVE NORMAL. 28.00Z MODELS INITIALIZED WELL. SOLUTIONS QUITE SIMILAR FOR TODAY THRU THU THEN DIVERGE WITH THE STRENGTH/TIMING OF THE SHORTWAVE AND SFC LOW/TROUGH TO MOVE ACROSS THE MID/UPPER MS VALLEY THU NIGHT. DPROG/DT OF 500MB HGTS AT 28.00Z SHOWED THE RUNS OF 26.00Z AND 27.00Z VERIFIED WELL ACROSS NOAM/EASTERN PAC WITH BETTER RUN-TO-RUN CONSISTENCY BY ECMWF. MODELS CONVERGING TOWARD A TIGHTER CONSENSUS THRU THU AS THE NEXT SHORTWAVE ENERGY FROM THE PACIFIC MOVES INTO THE CENTRAL/NORTHERN PLAINS BY 00Z FRI. FROM THERE MODELS DIVERGE WITH THE EVOLUTION OF THIS TROUGH AS IT MOVES EAST THRU THE REGION THU NIGHT/FRI. SOMEWHAT BETTER RUN-TO-RUN CONSISTENCY BY ECMWF THU NIGHT THRU FRI NIGHT...BUT COULD BE BETTER. CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED MODELS ON TRACK WITH THE SFC FEATURES OVER CENTRAL NOAM. PER WV IMAGERY...ECMWF/GEM LOOKED BETTER THAN NAM/GFS/MET WITH THE SHORTWAVE ENERGY IN THE TROUGH APPROACHING THE WEST COAST. ECMWF/GEM ARE A COUPLE OF THE SLOWER SOLUTIONS WITH THIS ENERGY AS IT CROSSES THE MID/UPPER MS VALLEY THU NIGHT/FRI. WITH ECMWF/GEM LOOKING BETTER AT 06Z...FAVORED A MODEL/ENSEMBLE CONSENSUS WEIGHTED TOWARD THEM ESPECIALLY THU NIGHT/FRI. HOWEVER GIVEN THE MODEL SPREAD FCST CONFIDENCE FALLS TO AVERAGE FOR THU NIGHT THRU FRI NIGHT. FOR THE SHORT TERM...THE LOW NORTH OF LK SUPERIOR MOVES QUICKLY AWAY FROM THE REGION TODAY. HOWEVER MDT 925 PRESSURE GRADIENT/WINDS REMAIN OVER THE AREA MUCH OF THE DAY. WITH PLENTY OF SUNSHINE AND MODEL SOUNDINGS INDICATING MIXING TO AROUND 900MB...WINDS WILL REMAIN BRISK/BREEZY TODAY. SFC RIDGE AXIS DRIFTS RATHER QUICKLY EAST ACROSS THE AREA TONIGHT...AND IS OVER EASTERN WI BY 12Z THU. WINDS BECOME LIGHT THIS EVENING BUT APPEARS WINDS MAY STIR/INCREASE A BIT LATE TONIGHT...ESPECIALLY OVER THE WEST HALF OF THE FCST AREA. COLDEST OF THE LOW LEVEL AIRMASS IS OVER THE EAST HALF OF THE FCST AREA TONIGHT...ALONG WITH THE LIGHTEST WINDS...WITH LOWS TONIGHT FALLING INTO THE 30S...COLDEST ALONG/NORTHEAST OF I-94. CONTINUED MENTION OF FROST OVER MAINLY THE EAST 2/3 OF THE FCST AREA TONIGHT. WILL LEAVE ANY POTENTIAL FROST HEADLINES TONIGHT TO DAY CREW WHO CAN MONITOR TEMPS/DEWPOINT/WIND TRENDS THRU THE EARLY AFTERNOON HOURS. HIGH CONTINUES TO MOVE OFF THU WITH INCREASING SOUTHEAST WINDS BETWEEN IT AND THE NEXT LOW/TROUGH INTO THE CENTRAL/NORTHERN PLAINS. MID/HIGH LEVEL MOISTURE AHEAD OF THIS TROUGH SPREADS EAST ACROSS THE AREA THU WITH THE INCREASE OF LOWER LEVEL MOISTURE REACHING THE WEST END OF THE FCST AREA EITHER LATE THU AFTERNOON OR THU EVENING. DEEPER/STRONGER OF THE FORCING FROM 925-850MB WARM/MOISTURE ADVECTION/ISENTROPIC LIFT THRU PV ADVECTION/DIVERGENCE ALOFT AHEAD OF THE SHORTWAVE MOVE INTO/ACROSS THE AREA THU NIGHT. ADDED A SMALL -SHRA CHANCE TO THE WEST END OF THE FCST AREA LATE THU AFTERNOON TO BLEND WITH NEIGHBORING GRIDS. RAISED RAIN CHANCES BY LATE THU NIGHT TOWARD 80 PERCENT WITH EVEN THE LOOSE MODEL CONSENSUS ALL PRODUCING SOME PRECIP OVER THE AREA. LEANING TOWARD THE SLOWER ECMWF/GEM FOR FRI...CONTINUED 20-50 PERCENT RAIN CHANCES...HIGHEST EAST...OVER THE FCST AREA FRI MORNING. CAPE LOOKS TO REMAIN LIMITED THU NIGHT/FRI MORNING. GIVEN THE STRENGTH/DEPTH OF THE FORCING/LIFT AND MODEL SOUNDINGS SHOWING NEAR NEUTRAL STABILITY ABOVE 850MB CONTINUED MENTION OF ISOLATED OR SCT TSRA IN THE LATE THU AFTERNOON THRU FRI MORNING PERIODS. WEAK SFC-500MB RIDGING BUILDS ACROSS THE AREA FOR LATER FRI/FRI NIGHT. LEANING TOWARD THE SLOWER ECMWF/GEM...ANY RETURNING LOWER LEVEL MOISTURE TRANSPORT/WARM ADVECTION WOULD REMAIN WEST OF THE FCST AREA FRI NIGHT AND REMOVED THE SMALL -SHRA/TSRA CHANCE. WITH PLENTY OF SUNSHINE TODAY...AT LEAST OVER THE CENTRAL/SOUTH PARTS OF THE FCST AREA...FAVORED WARMER OF THE GUIDANCE HIGHS. WITH THE COOL/DRY AIRMASS OVER THE AREA...FAVORED COOLER OF GUIDANCE LOWS TONIGHT. GUIDANCE HIGHS SIMILAR AND LOOK REASONABLE FOR THU. WITH THICKER CLOUDS/-SHRA...FAVORED WARMER OF GUIDANCE LOWS THU NIGHT. WITH TIMING UNCERTAINTIES...USED A BLEND OF GUIDANCE HIGHS/ LOWS FOR FRI/FRI NIGHT. .LONG TERM...SATURDAY THROUGH TUESDAY 356 AM CDT WED MAR 28 2012 SOME IMPROVEMENT OF CONSISTENCY AMONG 28.00Z MODEL RUNS FOR SAT INTO SUN...BUT BETWEEN MODEL AND RUN-TO-RUN CONSISTENCY CONTINUES TO LEAVE A LOT TO BE DESIRED BY SUN NIGHT AND FOR EARLY NEXT WEEK. AVERAGE CONFIDENCE SAT INTO SUN WITH IMPROVING MODEL CONSENSUS INDICATING SHORTWAVE RIDGING ALOFT CROSSING THE UPPER MIDWEST. WEEKEND TRENDING TO BE DRY OR ONLY VERY SMALL -SHRA/TSRA CHANCES AND A WARMING PERIOD WITH THE RIDGING/RISING HGTS AND PERSISTENT LOW LEVEL WARM ADVECTION OVER THE REGION. WITH THE VERY LOW CONSISTENCY AMONG THE MODELS BY MON/TUE...FCST CONFIDENCE THESE PERIODS QUITE LOW AS WELL. SOME SIGNAL AMONG ALL MODELS FOR TROUGHING TO MOVE INTO/ACROSS THE UPPER MIDWEST IN THE MON/TUE TIMEFRAME BUT DETAIL DIFFERENCE QUITE LARGE. ONE OF THE MOST EXTREME SOLUTIONS FOR EARLY NEXT WEEK IS THE UKMET...WITH A LARGE NEGATIVE TILT CENTRAL CONUS TROUGH AND A 984MB SFC LOW NEAR KDBQ MON EVENING. IMPLICATIONS FOR THIS WOULD NOT GO WELL WITH OUR WARM/EARLY START TO SPRING. WITH LOW CONFIDENCE AND ALL THE MODEL SPREAD STAYED NEAR THE MODEL/ENSEMBLE CONSENSUS FOR DAYS 6/7. DID RAISE HIGHS A BIT SUNDAY WITH STRONG RIDGING/WARMING AHEAD OF ANY TROUGHING/SFC LOW FOR EARLY NEXT WEEK. && .AVIATION...THROUGH 06Z THURSDAY 1150 PM CDT TUE MAR 27 2012 SOME WEAK PRESSURE RISES HAVE KEPT SOME GUSTINESS AT THE TAF SITES THIS PAST EVENING. THESE GUSTS SHOULD DIMINISH AS THE NIGHT WEARS ON WITH A RELAXING PRESSURE GRADIENT. 29.02Z RUC BUFKIT SOUNDINGS CONTINUE TO HINT AT THE POSSIBILITY OF A BROKEN CEILING AROUND 030K FEET AFTER 08Z. HOWEVER...28.00Z NAM LESS ROBUST WITH THIS MOISTURE AND GIVEN SATELLITE TRENDS WITH CLOUDS REMAINING NORTH OF THE TAF SITES...JUST WENT WITH A SCATTERED DECK OF CLOUDS AFTER 08Z. AFTER 14Z SOUNDINGS INDICATE MIXING AND COULD SEE SOME GUSTS TO BETWEEN 20 TO 23 KNOTS FOR A FEW HOURS. HIGH PRESSURE THEN BUILDS IN LATE WEDNESDAY AFTERNOON...WITH CLEAR SKIES AND LIGHT WINDS AFTER 01Z.650 PM CDT TUE MAR 27 2012 && .ARX WATCHES/WARNINGS/ADVISORIES... 356 AM CDT WED MAR 28 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION.....RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 PM CDT TUE MAR 27 2012 .SHORT TERM... 650 PM CDT TUE MAR 27 2012 WILL ALLOW WIND ADVISORY TO EXPIRE AT 7 PM. WINDS WILL CONTINUE TO DIMINISH EARLY THIS EVENING AS THE PRESSURE GRADIENT SLACKENS. UPDATED PRODUCTS WILL BE OUT SHORTLY. .LONG TERM...SATURDAY THROUGH TUESDAY 250 PM CDT TUE MAR 27 2012 CONSIDERABLE MODEL DIFFERENCES FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS FAVORS A CLOSED LOW AND LARGE TROUGH OVER THE ROCKIES WHILE THE EC IS WEAKER AND MORE PROGRESSIVE WITH THIS FEATURE. THUS...THE GFS WOULD HANG ONTO A RIDGE FOR MUCH OF THE EXTENDED PERIOD WHILE THE EC WOULD BRING IN PCPN CHANCES MON-TUE. A LOT OF INCONSISTENCIES WITHIN THE MODELS TOO...ESPECIALLY THE EC. WILL LEAN ON THE A GFS/CONSENSUS SOLUTION FOR THE DETAILS. THE WEEKEND IS SHAPING UP DRY THOUGH...AND WITH A RIDGE MORE LIKELY...HIGHS COULD POP BACK UP INTO THE 70S SUNDAY. && .AVIATION...THROUGH 06Z THURSDAY 1150 PM CDT TUE MAR 27 2012 SOME WEAK PRESSURE RISES HAVE KEPT SOME GUSTINESS AT THE TAF SITES THIS PAST EVENING. THESE GUSTS SHOULD DIMINISH AS THE NIGHT WEARS ON WITH A RELAXING PRESSURE GRADIENT. 29.02Z RUC BUFKIT SOUNDINGS CONTINUE TO HINT AT THE POSSIBILITY OF A BROKEN CEILING AROUND 030K FEET AFTER 08Z. HOWEVER...28.00Z NAM LESS ROBUST WITH THIS MOISTURE AND GIVEN SATELLITE TRENDS WITH CLOUDS REMAINING NORTH OF THE TAF SITES...JUST WENT WITH A SCATTERED DECK OF CLOUDS AFTER 08Z. AFTER 14Z SOUNDINGS INDICATE MIXING AND COULD SEE SOME GUSTS TO BETWEEN 20 TO 23 KNOTS FOR A FEW HOURS. HIGH PRESSURE THEN BUILDS IN LATE WEDNESDAY AFTERNOON...WITH CLEAR SKIES AND LIGHT WINDS AFTER 01Z. && .ARX WATCHES/WARNINGS/ADVISORIES... 650 PM CDT TUE MAR 27 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RABERDING LONG TERM......RIECK AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1107 AM EDT WED MAR 28 2012 .SYNOPSIS... LOW PRESSURE APPROACHES TODAY AND MOVES TO THE EAST TONIGHT. AN ASSOCIATED COLD FRONT WILL FOLLOW. HIGH PRESSURE BUILDS IN FOR THURSDAY NIGHT INTO FRIDAY. LOW PRESSURE APPROACHES THE REGION FRIDAY NIGHT...TRACKING JUST SOUTH OF THE AREA. HIGH PRESSURE BUILDS IN FOR SUNDAY. A WARM FRONT LIFTS NORTH OF THE REGION SUNDAY NIGHT. COLD FRONT MOVES THROUGH MONDAY NIGHT...WITH HIGH PRESSURE BUILDING IN FOR MID-WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FORECAST GENERALLY ON TRACK. MADE ADJUSTMENTS TO HOURLY DEW POINTS WHICH HAVE RISEN SLIGHTLY QUICKER THAN FORECAST. ALSO FINE TUNED THE POPS AND WX TO BETTER REFLECT TIMING OF SHOWERS. SOME SHOWERS WILL HAVE EMBEDDED THUNDER WITH IT SO WILL INCLUDE CHANCE OF THUNDER EVERYWHERE IN THE GRIDS. OTHERWISE...WARM AIR ADVECTION UNDERWAY AS SFC HIGH PRESSURE HAS PASSED WELL TO THE SOUTH. RIDGING ALOFT...WITH RIDGE AXIS TO THE EAST...OCCURRING AHEAD OF DIGGING TROUGH TRAVERSING ACROSS THE GREAT LAKES REGION. SFC LOW PRESSURE MOVES ACROSS THE SAINT LAWRENCE VALLEY AND PASSES ACROSS NEW ENGLAND THIS AFTERNOON. LOOKING AT SREF/GEFS DATA...PROBABILITY OF AT LEAST MEASURABLE QPF HIGHER THAN MET MOS SUGGESTS. PW VALUES INCREASE AHEAD OF THE COLD FRONT THIS AFTERNOON...WITH THETA E RIDGE EXTENDED ACROSS THE AREA AND LAYER PW PERCENTAGE WELL ABOVE NORMAL. SOME JET SUPPORT ALOFT FOR POSSIBLE CONVECTION. DEPENDING ON ANY SUNSHINE...MOS NUMBERS APPEAR REASONABLE WITH 60S WEST...AND 50S EAST DUE TO SW FLOW OFF COOL WATER. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... SHORTWAVE PIVOTS ACROSS THE NORTHEAST TONIGHT AND THURSDAY...WITH MUCH DRIER AIR USHERED IN IN DEEP NW FLOW. SFC LOW PRESSURE TRACKS OFF THE NEW ENGLAND COAST TONIGHT...DRAGGING A COLD FRONT THROUGH. WEAK UPPER SUPPORT/ASSOC LIFT FOR WIDESPREAD SHOWERS...AND DRY AIR SHOULD KEEP ANY PRECIP POTENTIAL TO A MINIMUM TONIGHT INTO EARLY THURSDAY. IT WILL BE COLDER (ALTHOUGH STILL ABOVE NORMAL)...AND MOS NUMBERS LOOK REASONABLE. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGH PRESSURE BUILDS IN FOR FRIDAY...KEEPING THE AREA DRY. SOME MODEL DIFFERENCE AS NAM AND GFS HAVE AN UPPER LEVELS TROUGH AND ASSOCIATED SURFACE LOW MOVE EAST FROM THE MID-WEST...WITH PRECIPITATION BEGINNING FRIDAY NIGHT. THE LOW IS FORECAST TO PASS WELL TO OUR SOUTH BY 12Z ON SATURDAY...WITH A PERIOD OF MODERATE TO HEAVY RAIN LATE FRIDAY NIGHT. GEM IS ABOUT 12 HOURS SLOWER...PUSHING THE LOW OFFSHORE BY SUNDAY 00Z. THE ONSET OF PRECIPITATION FOR THE GEM/NAM/GFS ARE SIMILAR HOWEVER. THE GEM KEEPS PRECIPITATION IN THROUGH SATURDAY NIGHT. THE ECMWF IS AN OUTLIER...NOT PUSHING THE LOW OFFSHORE UNTIL SATURDAY NIGHT...WITH THE AREA NOT DRYING OUT UNTIL LATE SUNDAY NIGHT...THEREFORE...LEANED WITH THE NAM/GFS SOLUTION GFS HAS A WARM FRONT THAT LIFTS NORTH OF THE AREA ON SUNDAY...WHILE THE ECMWF DOES NOT HAVE THIS OCCURRING UNTIL MONDAY. THEY THEN COME INTO AGREEMENT WITH COLD FRONTAL PASSAGE MONDAY NIGHT AS A SURFACE LOW TRACKS FROM THE GREAT LAKES REGION INTO SOUTHERN CANADA. THE GEM IS THE OUTLIER IN THIS TIME PERIOD AS IT HAS A SURFACE LOW IN SOUTHERN CANADA DIVING SOUTHEASTWARD...MOVING OVER OUR AREA...AND OFFSHORE BYE MONDAY MORNING. GFS AND ECMWF ARE IN AGREEMENT WITH ANOTHER COLD FRONT MOVING THROUGH TUESDAY. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... HIGH PRES SOUTH OF THE AREA CONTINUES TO DEPART AS A FRONTAL SYSTEM MOVES ACROSS THE REGION LATER TODAY. GENERALLY A VFR FORECAST WITH CIGS LOWERING TO AROUND 5K FT...THOUGH BRIEF PERIODS OF MVFR POSSIBLE IN -SHRA THIS AFTERNOON. TIMING FOR FIRST ROUND OF ELEVATED CONVECTION WITH -SHRA IN TEMPO GROUPS IS BASED ON LATEST RADAR TRENDS...WHICH AGREES FAIRLY WELL WITH HRRR GUIDANCE. EXCEPT AT KSWF...WHICH SHOULD HAVE A -TSRA PASS JUST TO THE NORTH WITHIN THE NEXT HOUR...HAVE REFRAINED FROM INCLUDING TS/CB IN TAFS AS CONFIDENCE IN THUNDER AT ANY GIVEN LOCATION IS LOW...BUT WILL MONITOR AND AMEND AS NEEDED. A SECOND ROUND OF CONVECTION IS POSSIBLE LATE THIS AFTERNOON/EARLY THIS EVENING WITH BEST TIMING OF -SHRA REFLECTED IN TEMPO GROUP IN TAFS. SSW WINDS 10-15KT WITH GUSTS TO AROUND 20KT TO GET STARTED BECOME MORE SW AND GUSTS INCREASE TO 20-25KT THIS AFTERNOON. FRONTAL SYSTEM DEPARTS THIS EVENING...AND WINDS SHIFT TO A W...THEN NW FLOW...AND DECREASE TO AROUND 10 KT. WINDS THEN INCREASE TO 10-15 KT WITH 20-25 KT GUSTS TOWARDS DAYBREAK THURSDAY. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. KISP FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND SPEED/DIRECTION...AND TIMING OF -SHRA AND ANY TS THIS AFTERNOON. OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY... .THURSDAY...VFR. GUSTY NW FLOW...DIMINISHING LATE. .FRIDAY-SUNDAY...VFR. && .MARINE... A TIGHTENING PRESSURE GRADIENT IS EXPECTED TODAY AS HIGH PRESSURE SETTLES WELL TO THE SOUTH AND LOW PRESSURE APPROACHES FROM THE NORTH. GUSTY SOUTHWEST WINDS ARE ANTICIPATED...AND OCEAN SEAS WILL BUILD TO SCA LEVELS. OTHER WATERS SHOULD FALL JUST SHORT OF SCA CRITERIA WINDS...BUT THIS WILL NEED TO BE WATCHED. SEAS/WAVES WILL BECOME CHOPPY AS A RESULT. BY TONIGHT...THE LOW PRESSURE PASSES JUST NORTHEAST...ALLOWING WINDS TO TEMPORARILY LIGHTEN. HOWEVER...SW WINDS SHIFT TO THE NW AND WILL BECOME GUSTY ONCE AGAIN. SCA WINDS ARE ANTICIPATED LATE TONIGHT AND THROUGH THURSDAY AS THIS LOW PULLS AWAY. EXPECT SCA CONDITIONS ACROSS ALL WATERS THURSDAY. WAVES BEGIN TO BUILD LATE FRIDAY NIGHT...COMING UP ABOVE 5 FT ON SATURDAY AS LOW PRESSURE APPROACHES AND MOVES THROUGH THE WATERS. WINDS WILL ALSO BE ON THE INCREASE AS THE PRESSURE GRADIENT INCREASES. WINDS WILL GUST ABOVE 25 KT...BUT WILL DIMINISH SATURDAY NIGHT. WAVES INCREASE ABOVE 5 FT AGAIN MONDAY NIGHT ON A STRONG SOUTHWESTERLY FLOW...AND REMAIN ELEVATED THROUGH TUESDAY NIGHT. && .FIRE WEATHER... DEPENDING ON FINE FUEL MOISTURE AFTER POSSIBLE WETTING RAINS TODAY...THURSDAY COULD BE ANOTHER DAY OF CONCERN IN THE NYC METRO AREA...WITH RH LOWERING TO NEAR 30 PERCENT AND WINDS GUSTING TO 25 MPH AFTER A COLD FRONTAL PASSAGE. CONFIDENCE NOT HIGH ENOUGH TO WARRANT A FIRE WEATHER WATCH AT THIS TIME FOR THURSDAY. && .HYDROLOGY... NO SIGNIFICANT QPF IS EXPECTED MID WEEK. ABOUT HALF AN INCH OF RAINFALL IS EXPECTED FRIDAY NIGHT INTO SATURDAY. NO FLOODING IS EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT THURSDAY FOR ANZ330- 335-338-340-345. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ350-353- 355. && $$ SYNOPSIS...JP/PW NEAR TERM...BC/PW SHORT TERM...PW LONG TERM...JP AVIATION...MALOIT/MPS MARINE...JP/PW FIRE WEATHER... HYDROLOGY...JP/PW
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1048 AM EDT WED MAR 28 2012 .UPDATE... AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... A COLD FRONT SLOWLY SAGGING SOUTH THROUGH SOUTHERN CENTRAL INDIANA WILL KEEP LOW CHANCES FOR THUNDER AROUND THE SOUTHERN COUNTIES UNTIL MID AFTERNOON. MEANWHILE HIGH PRESSURE WILL BUILD IN FROM THE NORTH AND OVERSPREAD THE AREA BRINGING CLEARING SKIES. THE RIDGING WILL RESULT IN DRY WEATHER THROUGH FRIDAY WHEN THE NEXT DISTURBANCE ENTERS THE FORECAST AREA. BEYOND THAT...QUIET CONDITIONS FOR THE REMAINDER OF THE WEEKEND...AND THEN ANOTHER SYSTEM OVER THE GREAT LAKES REGION IS PROGGED FOR MONDAY. ITS ASSOCIATED COLD FRONT WILL TRIGGER THUNDERSTORM ACTIVITY ACROSS CENTRAL INDIANA. && .NEAR TERM /REST OF TODAY/... COLD FRONT HAS SLOWED IN ITS MOVEMENT THROUGH THE AREA AND CONTINUES TO SLOWLY SAG SOUTH. REMOVED POPS FROM AREAS NORTH OF THE FRONT...BUT EVEN THOUGH RPECIP HAS FOR THE MOST PART LEFT THE AREA RAPID UPDATE MODELS SUCH AS HRRR AND VSREFS SHOW REDEVELOPMENT OVER THE NEXT FEW HOURS ALONG/AHEAD OF THE FRONT SO WILL KEEP A LOW CHANCE POPS GOING ACROSS THE SOUTH INTO THE MID AFTERNOON. OTHERWISE HIGH PRESSURE CONTINUES TO BUILD IN FROM THE NORTH AND WILL CLEAR SKIES OUT FROM NORTH TO SOUTH THROUGH THE DAY. TEMPS...MODELS DO NOT SEEM TO BE ACCOUNTING FOR CLEARING VERY WELL...THUS SEEM A TAD LOW ON TODAY/S HIGHS. AS A RESULT...TRENDED A FEW DEGREES ABOVE GUIDANCE DUE TO SUFFICIENT SUNSHINE LATER TODAY. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... THE MAIN FOCUS OF THE SHORT TERM IS THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS ON FRIDAY. RIDGE WILL RE-ESTABLISH ITSELF ACROSS FORECAST AREA TONIGHT BRINGING DRY CONDITIONS THROUGH FRIDAY. HOWEVER...THE RIDGE WILL BREAK DOWN ON THURSDAY NIGHT AS A 500 MB SHORTWAVE APPROACHES CENTRAL INDIANA. THE GFS AND EURO ARE A TAD MORE PROGRESSIVE THAN THE NAM IN REGARD TO PRECIP ON THURSDAY NIGHT...BUT INCREASING ISENTROPIC LIFT SUPPORTS POPS AS EARLY AS FRI 06Z. THE BEST LIFT WILL OCCUR IN THE FRI 12-18Z TIME FRAME AS SHORT WAVE AND SURFACE LOW PASS OVER CENTRAL INDIANA. SO...INTRODUCED DEFINITE POPS INTO GRIDS DURING THAT PERIOD...WHICH MAY HAVE TO BE EXTENDED INTO FRIDAY NIGHT DEPENDING ON POSITION OF ASSOCIATED COLD FRONT. TEMPS...STUCK WITH A BLEND UNTIL FRIDAY. THAT/S WHEN MODELS STARTED HAVING A LITTLE TROUBLE WITH THE AFOREMENTIONED DISTURBANCE. TRENDED ON THE COOLER SIDE FOR DAYTIME HIGHS...AND LEANED ON THE WARMER SIDE FOR FRIDAY NIGHT LOWS DUE TO INCREASED CLOUD COVER. && .LONG TERM /SATURDAY THROUGH TUESDAY NIGHT/... THIS PERIOD BEGINS WITH SOME REMAINING LOW CHANCES FOR POPS AS FRONT IS PROGGED TO BE DROPPING SOUTH OF THE AREA BY SATURDAY AFTERNOON. MODELS HAVE BEEN INCREASINGLY PROGRESSIVE WITH THIS FRONT SO HAVE BACKED OFF ON POPS SLIGHTLY FOR SATURDAY. UPPER RIDGING BUILDS IN EARNEST BY SATURDAY NIGHT...AND PROVIDES QUIET DRY AND WARMER WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY NIGHT. ANOTHER FRONT IS PROGGED TO APPROACH THE REGION SUNDAY NIGHT AND CROSS THE AREA MONDAY INTO MONDAY EVENING...BRINGING CHANCES FOR THUNDER BACK INTO THE FORECAST. RIDGE BUILDS BACK IN BY TUESDAY. && .AVIATION /DISCUSSION FOR 281500Z KIND TAF UPDATE/... MINOR CHANGES MAKED TO KIND TAF PER OBSERVATIONS. OTHERWISE...NO OTHER CHANGES NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION FOLLOWS... VFR CONDITIONS EXPECTED THROUGHOUT THE FORECAST PERIOD. AS OF 7 AM THIS MORNING...FRONTAL BOUNDARY JUST ABOUT READY TO DROP SOUTH OF ALL THE FORECAST TERMINALS. WILL START OFF THE PERIOD WITHOUT ANY MENTION OF SHOWERS (EXCEPT FOR POSSIBLY KEEPING SOME IN FOR KBMG FOR THE FIRST HALF HOUR TO HR) JUST SOME SCATTERED CU IN THE WAKE OF THE FRONT. CLOUDS SHOULD QUICKLY CLEAR BY MIDDAY AS DRIER AIR ADVECTS INTO THE REGION BEHIND THE FRONT. PRESENCE OF STRONGER WINDS ALOFT THROUGH THE DAY AND MIXING LEVELS UP TO AROUND 5KFT WILL PROMOTE W/NW WIND GUSTS AT 25-30KTS FOR MUCH OF THE AFTERNOON. WINDS WILL VEER TO NORTHERLY AND LIGHTEN DURING THE EVENING AS A RIDGE OF HIGH PRESSURE EXPANDS INTO THE REGION FROM THE NORTHWEST. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD/CP NEAR TERM...TDUD/CP SHORT TERM...TDUD LONG TERM....SMF AVIATION...SMF/JH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1044 AM EDT WED MAR 28 2012 .UPDATE... THE SYNOPSIS AND NEAR TERM SECTION HAVE BEEN UPDATED BELOW. && .SYNOPSIS... A COLD FRONT SLOWLY SAGGING SOUTH THROUGH SOUTHERN CENTRAL INDIANA WILL KEEP LOW CHANCES FOR THUNDER AROUND THE SOUTHERN COUNTIES UNTIL MID AFTERNOON. MEANWHILE HIGH PRESSURE WILL BUILD IN FROM THE NORTH AND OVERSPREAD THE AREA BRINGING CLEARING SKIES. THE RIDGING WILL RESULT IN DRY WEATHER THROUGH FRIDAY WHEN THE NEXT DISTURBANCE ENTERS THE FORECAST AREA. BEYOND THAT...QUIET CONDITIONS FOR THE REMAINDER OF THE WEEKEND...AND THEN ANOTHER SYSTEM OVER THE GREAT LAKES REGION IS PROGGED FOR MONDAY. ITS ASSOCIATED COLD FRONT WILL TRIGGER THUNDERSTORM ACTIVITY ACROSS CENTRAL INDIANA. && .NEAR TERM /REST OF TODAY/... COLD FRONT HAS SLOWED IN ITS MOVEMENT THROUGH THE AREA AND CONTINUES TO SLOWLY SAG SOUTH. REMOVED POPS FROM AREAS NORTH OF THE FRONT...BUT EVEN THOUGH RPECIP HAS FOR THE MOST PART LEFT THE AREA RAPID UPDATE MODELS SUCH AS HRRR AND VSREFS SHOW REDEVELOPMENT OVER THE NEXT FEW HOURS ALONG/AHEAD OF THE FRONT SO WILL KEEP A LOW CHANCE POPS GOING ACROSS THE SOUTH INTO THE MID AFTERNOON. OTHERWISE HIGH PRESSURE CONTINUES TO BUILD IN FROM THE NORTH AND WILL CLEAR SKIES OUT FROM NORTH TO SOUTH THROUGH THE DAY. TEMPS...MODELS DO NOT SEEM TO BE ACCOUNTING FOR CLEARING VERY WELL...THUS SEEM A TAD LOW ON TODAY/S HIGHS. AS A RESULT...TRENDED A FEW DEGREES ABOVE GUIDANCE DUE TO SUFFICIENT SUNSHINE LATER TODAY. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... THE MAIN FOCUS OF THE SHORT TERM IS THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS ON FRIDAY. RIDGE WILL RE-ESTABLISH ITSELF ACROSS FORECAST AREA TONIGHT BRINGING DRY CONDITIONS THROUGH FRIDAY. HOWEVER...THE RIDGE WILL BREAK DOWN ON THURSDAY NIGHT AS A 500 MB SHORTWAVE APPROACHES CENTRAL INDIANA. THE GFS AND EURO ARE A TAD MORE PROGRESSIVE THAN THE NAM IN REGARD TO PRECIP ON THURSDAY NIGHT...BUT INCREASING ISENTROPIC LIFT SUPPORTS POPS AS EARLY AS FRI 06Z. THE BEST LIFT WILL OCCUR IN THE FRI 12-18Z TIME FRAME AS SHORT WAVE AND SURFACE LOW PASS OVER CENTRAL INDIANA. SO...INTRODUCED DEFINITE POPS INTO GRIDS DURING THAT PERIOD...WHICH MAY HAVE TO BE EXTENDED INTO FRIDAY NIGHT DEPENDING ON POSITION OF ASSOCIATED COLD FRONT. TEMPS...STUCK WITH A BLEND UNTIL FRIDAY. THAT/S WHEN MODELS STARTED HAVING A LITTLE TROUBLE WITH THE AFOREMENTIONED DISTURBANCE. TRENDED ON THE COOLER SIDE FOR DAYTIME HIGHS...AND LEANED ON THE WARMER SIDE FOR FRIDAY NIGHT LOWS DUE TO INCREASED CLOUD COVER. && .LONG TERM /SATURDAY THROUGH TUESDAY NIGHT/... THIS PERIOD BEGINS WITH SOME REMAINING LOW CHANCES FOR POPS AS FRONT IS PROGGED TO BE DROPPING SOUTH OF THE AREA BY SATURDAY AFTERNOON. MODELS HAVE BEEN INCREASINGLY PROGRESSIVE WITH THIS FRONT SO HAVE BACKED OFF ON POPS SLIGHTLY FOR SATURDAY. UPPER RIDGING BUILDS IN EARNEST BY SATURDAY NIGHT...AND PROVIDES QUIET DRY AND WARMER WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY NIGHT. ANOTHER FRONT IS PROGGED TO APPROACH THE REGION SUNDAY NIGHT AND CROSS THE AREA MONDAY INTO MONDAY EVENING...BRINGING CHANCES FOR THUNDER BACK INTO THE FORECAST. RIDGE BUILDS BACK IN BY TUESDAY. && .AVIATION /DISCUSSION FOR 281200Z TAF ISSUANCE/... VFR CONDITIONS EXPECTED THROUGHOUT THE FORECAST PERIOD. AS OF 7 AM THIS MORNING...FRONTAL BOUNDARY JUST ABOUT READY TO DROP SOUTH OF ALL THE FORECAST TERMINALS. WILL START OFF THE PERIOD WITHOUT ANY MENTION OF SHOWERS (EXCEPT FOR POSSIBLY KEEPING SOME IN FOR KBMG FOR THE FIRST HALF HOUR TO HR) JUST SOME SCATTERED CU IN THE WAKE OF THE FRONT. CLOUDS SHOULD QUICKLY CLEAR BY MIDDAY AS DRIER AIR ADVECTS INTO THE REGION BEHIND THE FRONT. PRESENCE OF STRONGER WINDS ALOFT THROUGH THE DAY AND MIXING LEVELS UP TO AROUND 5KFT WILL PROMOTE W/NW WIND GUSTS AT 25-30KTS FOR MUCH OF THE AFTERNOON. WINDS WILL VEER TO NORTHERLY AND LIGHTEN DURING THE EVENING AS A RIDGE OF HIGH PRESSURE EXPANDS INTO THE REGION FROM THE NORTHWEST. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD/CP NEAR TERM...TDUD/CP SHORT TERM...TDUD LONG TERM....SMF AVIATION...SMF
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1050 AM EDT WED MAR 28 2012 .SYNOPSIS... A COLD FRONT WILL BRING SHOWERS WITH THE CHANCE OF THUNDERSTORMS TO THE UPPER OHIO VALLEY REGION TODAY. SEASONABLY COOL WEATHER WILL FOLLOW FOR THURSDAY...BUT LOOK FOR INCREASED RAIN CHANCES AGAIN ON FRIDAY AS LOW PRESSURE APPROACHES THE AREA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A SURFACE WARM FRONT IS ADVANCING NORTHEASTWARD ACROSS THE AREA THIS MORNING...WITH ELEVATED CONVECTION GENERALLY DRIVEN BY STEEP MID-LEVEL LAPSE RATES SPAWNING THUNDERSTORMS THAT HAVE CROSSED THE PITTSBURGH METRO AREA THIS MORNING. THUNDERSTORMS CONTINUE TO BISECT THE FORECAST AREA...WITH THEIR SOUTHWARD PROGRESS LIKELY BECOMING INCREASINGLY RETARDED AS THE AFTERNOON ENSUES DUE TO MID- LEVEL FORCING STARTING TO SHEAR OFF TO THE EAST. SHEAR IN THE 0-6 KM LAYER WILL REMAIN ROUGHLY IN THE 50 KT RANGE THROUGH THE AFTERNOON...WHILE INSTABILITY SHOULD INCREASE AHEAD OF A SLOWLY SOUTHWARD ADVANCING COLD FRONT BY THE AFTERNOON...THIS MAY LEAD TO A CHANCE OF SEVERE THUNDERSTORMS YET AGAIN THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. FRIES PREVIOUS... LOW PRESSURE MOVING ACROSS THE NORTHERN LAKES WILL PULL A COLD FRONT ACROSS THE UPPER OHIO REGION TODAY. STRONG WARM ADVECTION IN ADVANCE OF THE LOW HAS DEVELOPED A SHALLOW INVERSION AND WILL INITIALLY CAP THE BOUNDARY LAYER. HOWEVER...SUFFICIENT FUEL/INSTABILITY IS INDICATED FOR DEVELOPMENT OF SOME ELEVATED SHOWERS/POSSIBLE THUNDERSTORMS THIS MORNING...WHICH SHOULD BECOME MORE SURFACE BASED AS THE FRONT AND THE DAY PROGRESS. OVERALL SEVERE POTENTIAL REMAINS LOW DESPITE FAVORABLE DEEP LAYER SHEAR WITH LIMITATIONS IMPOSED BY A LACK OF INSTABILITY. MODELS ARE IN GENERAL AGREEMENT IN MORE RAPID PASSAGE OF THE FRONT THAN PREVIOUSLY DEPICTED...SO ADJUSTMENTS THIS MORNING FEATURE FADING PRECIP PROBABILITIES DURING THE AFTERNOON. ALSO OF INTEREST FOR THE AFTERNOON IS THE AFOREMENTIONED STRONG WIND FIELD IN CONJUNCTION WITH THE STEEPENING LOW LAPSE RATE AS DISPLAYED VIA MODEL SOUNDINGS. WIND GUSTS HAVE THUS BEEN INCREASED...BUT ARE EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS. COLDER AIR IS PROJECTED TO ADVECT OFF THE LAKES TONIGHT...AND LOW INVERSION LEVELS SHOULD PRECLUDE MUCH THE WAY OF SHOWERS. SMALL PRECIP PROBABILITIES WERE TWEAKED TO FAVOR AREAS IN LEE OF THE LAKES AND THE RIDGES. PROJECTED TEMPERATURE PROFILE ALSO IS INDICATIVE OF SOME FROZEN PRECIP OVER NORTHERN COUNTIES...SNOW SHOWER MENTION WAS THUS ADDED. NEAR TERM TEMPERATURES WERE FORECAST USING TWEAKED SREF MEANS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... BUILDING HIGH PRESSURE SHOULD SNUFF ANY LINGERING SHOWERS BY MIDDAY THURSDAY...AND CONTINUED COLD ADVECTION SHOULD HOLD TEMPERATURES A FEW DEGREES BELOW THE SEASONAL NORMALS. THE SURFACE HIGH PRESSURE AXIS IS NAM/GFS FORECAST TO SLIDE ACROSS THE UPPER OHIO ON THURSDAY NIGHT...AND THE AIRMASS WILL BE PLENTY DRY FOR A PERIOD OF RADIATIONAL COOLING BEFORE WARM...MOIST ADVECTION RESUMES IN ADVANCE OF MIDWESTERN LOW PRESSURE. ANOTHER FREEZE IS THUS FORECAST...BUT DURATION/MAGNITUDE LOOKS TO BE LIMITED AS MID LEVEL CLOUDINESS INCREASES. ANOTHER SHORTWAVE IS FORECAST FOR A FRIDAY APPROACH AND SATURDAY EXIT...HENCE CHANCE POPS WERE MAINTAINED FOR THE CLOSE OF THE WORK WEEK...FOLLOWED BY DIMINISHED NUMBERS INTO THE WEEKEND. SHORT TERM TEMPERATURES SHOULD AVERAGE OUT FAIRLY CLOSE TO NORMAL AND WERE FORECAST USING A BLEND OF SREF AND GFS MOS. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... PROGRESSIVE PATTERN IS GFS/ECMWF DEPICTED FOR THE LONG TERM PERIOD AND AS SENSIBLE WEATHER WILL THUS BE SHORTWAVE DEPENDENT...FORECAST WILL GENERALLY BE OF PERSISTENCE AND ALTERATIONS MINIMAL THIS MORNING. WITH THE JET PROJECTED TO MEANDER OVER...OR NORTH OF THE GREAT LAKES...TEMPERATURES WERE FORECAST ABOVE THE SEASONAL AVERAGES USING TWEAKED HPC GUIDANCE. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... MAIN AVIATION CONCERN THROUGH 14Z WILL BE LOW LEVEL WIND SHEAR. RECENT NAM MODEL PROFILES SHOW A VERY STRONG AND SHALLOW SURFACE INVERSION THIS MORNING, WITH BASE 1 KFT AGL, HAVING SURFACE WINDS FROM THE SOUTH AT 5-10 KTS. RADAR VERTICAL WIND PROFILES AND NAM MODEL PROFILES SHOW WINDS FROM THE SOUTHWEST AND WEST 35-50 KTS IN THE LAYER 1-2 KFT AGL WILL CONTINUE TODAY. BLEND OF HIGH RESOLUTION MODEL OUTPUT SHOW VERTICAL MIXING, ACCOMPANYING THE COLD FRONTAL PASSAGE 14Z-18Z, DEEPENING THE SURFACE LAYER WHICH WILL THEN TAP THE FAST WINDS ALOFT AND CAUSE SOUTHWEST TO WEST SURFACE WINDS TO GUST TO 25-30 KTS THROUGH 22Z. FLIGHT CONDITIONS SHOULD BE MAINLY VFR THROUGH 06Z, DESPITE PASSAGE OF FRONTAL BAND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS 14Z-18Z, AS HAVE TOO LOW CONFIDENCE TO MENTION. TIMING OF SHOWERS HAS BEEN BASED ON RECENT WRF-NMM AND HRRR MODEL OUTPUT. COLD POOL STRATOCUMULUS LATE TONIGHT INTO THURSDAY MORNING MAY PROMOTE A PERIOD OF MVFR CEILINGS. OUTLOOK...THURSDAY THROUGH SUNDAY... VFR THURSDAY AFTERNOON INTO FRIDAY. RESTRICTIONS THEN POSSIBLE DUE TO SHOWERS FROM A LOW PRESSURE SYSTEM PASSAGE FRIDAY NIGHT INTO SATURDAY, AND LINGERING COLD POOL CLOUDS SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
826 AM EDT WED MAR 28 2012 .SYNOPSIS... A COLD FRONT WILL BRING SHOWERS WITH THE CHANCE OF THUNDERSTORMS TO THE UPPER OHIO VALLEY REGION TODAY. SEASONABLY COOL WEATHER WILL FOLLOW FOR THURSDAY...BUT LOOK FOR INCREASED RAIN CHANCES AGAIN ON FRIDAY AS LOW PRESSURE APPROACHES THE AREA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ONGOING THUNDERSTORMS IN THE NORTHERN HALF OF THE CWA HAVE BEEN YIELDING REPORTS OF NEARLY QUARTER SIZED HAIL. INSTABILITY LOOKS TO BE VERY LEAN...HOWEVER 50-60 KTS OF 0-6 KM BULK UNIDIRECTIONAL SHEAR ARE MANAGING TO YIELD DECENT ENOUGH SUPPORT TO MANAGE TO SUSTAIN BRIEFLY STRONG UPDRAFTS. THE FORECAST HAS BEEN UPDATED TO INCLUDE GUSTY WINDS AND LARGE HAIL WITH THE THUNDERSTORMS ACROSS THE NORTHERN TIER OF COUNTIES THIS MORNING. FRIES PREVIOUS... LOW PRESSURE MOVING ACROSS THE NORTHERN LAKES WILL PULL A COLD FRONT ACROSS THE UPPER OHIO REGION TODAY. STRONG WARM ADVECTION IN ADVANCE OF THE LOW HAS DEVELOPED A SHALLOW INVERSION AND WILL INITIALLY CAP THE BOUNDARY LAYER. HOWEVER...SUFFICIENT FUEL/INSTABILITY IS INDICATED FOR DEVELOPMENT OF SOME ELEVATED SHOWERS/POSSIBLE THUNDERSTORMS THIS MORNING...WHICH SHOULD BECOME MORE SURFACE BASED AS THE FRONT AND THE DAY PROGRESS. OVERALL SEVERE POTENTIAL REMAINS LOW DESPITE FAVORABLE DEEP LAYER SHEAR WITH LIMITATIONS IMPOSED BY A LACK OF INSTABILITY. MODELS ARE IN GENERAL AGREEMENT IN MORE RAPID PASSAGE OF THE FRONT THAN PREVIOUSLY DEPICTED...SO ADJUSTMENTS THIS MORNING FEATURE FADING PRECIP PROBABILITIES DURING THE AFTERNOON. ALSO OF INTEREST FOR THE AFTERNOON IS THE AFOREMENTIONED STRONG WIND FIELD IN CONJUNCTION WITH THE STEEPENING LOW LAPSE RATE AS DISPLAYED VIA MODEL SOUNDINGS. WIND GUSTS HAVE THUS BEEN INCREASED...BUT ARE EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS. COLDER AIR IS PROJECTED TO ADVECT OFF THE LAKES TONIGHT...AND LOW INVERSION LEVELS SHOULD PRECLUDE MUCH THE WAY OF SHOWERS. SMALL PRECIP PROBABILITIES WERE TWEAKED TO FAVOR AREAS IN LEE OF THE LAKES AND THE RIDGES. PROJECTED TEMPERATURE PROFILE ALSO IS INDICATIVE OF SOME FROZEN PRECIP OVER NORTHERN COUNTIES...SNOW SHOWER MENTION WAS THUS ADDED. NEAR TERM TEMPERATURES WERE FORECAST USING TWEAKED SREF MEANS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... BUILDING HIGH PRESSURE SHOULD SNUFF ANY LINGERING SHOWERS BY MIDDAY THURSDAY...AND CONTINUED COLD ADVECTION SHOULD HOLD TEMPERATURES A FEW DEGREES BELOW THE SEASONAL NORMALS. THE SURFACE HIGH PRESSURE AXIS IS NAM/GFS FORECAST TO SLIDE ACROSS THE UPPER OHIO ON THURSDAY NIGHT...AND THE AIRMASS WILL BE PLENTY DRY FOR A PERIOD OF RADIATIONAL COOLING BEFORE WARM...MOIST ADVECTION RESUMES IN ADVANCE OF MIDWESTERN LOW PRESSURE. ANOTHER FREEZE IS THUS FORECAST...BUT DURATION/MAGNITUDE LOOKS TO BE LIMITED AS MID LEVEL CLOUDINESS INCREASES. ANOTHER SHORTWAVE IS FORECAST FOR A FRIDAY APPROACH AND SATURDAY EXIT...HENCE CHANCE POPS WERE MAINTAINED FOR THE CLOSE OF THE WORK WEEK...FOLLOWED BY DIMINISHED NUMBERS INTO THE WEEKEND. SHORT TERM TEMPERATURES SHOULD AVERAGE OUT FAIRLY CLOSE TO NORMAL AND WERE FORECAST USING A BLEND OF SREF AND GFS MOS. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... PROGRESSIVE PATTERN IS GFS/ECMWF DEPICTED FOR THE LONG TERM PERIOD AND AS SENSIBLE WEATHER WILL THUS BE SHORTWAVE DEPENDENT...FORECAST WILL GENERALLY BE OF PERSISTENCE AND ALTERATIONS MINIMAL THIS MORNING. WITH THE JET PROJECTED TO MEANDER OVER...OR NORTH OF THE GREAT LAKES...TEMPERATURES WERE FORECAST ABOVE THE SEASONAL AVERAGES USING TWEAKED HPC GUIDANCE. && .AVIATION /13Z WEDNESDAY THROUGH SUNDAY/... MAIN AVIATION CONCERN THROUGH 14Z WILL BE LOW LEVEL WIND SHEAR. RECENT NAM MODEL PROFILES SHOW A VERY STRONG AND SHALLOW SURFACE INVERSION THIS MORNING, WITH BASE 1 KFT AGL, HAVING SURFACE WINDS FROM THE SOUTH AT 5-10 KTS. RADAR VERTICAL WIND PROFILES AND NAM MODEL PROFILES SHOW WINDS FROM THE SOUTHWEST AND WEST 35-50 KTS IN THE LAYER 1-2 KFT AGL WILL CONTINUE TODAY. BLEND OF HIGH RESOLUTION MODEL OUTPUT SHOW VERTICAL MIXING, ACCOMPANYING THE COLD FRONTAL PASSAGE 14Z-18Z, DEEPENING THE SURFACE LAYER WHICH WILL THEN TAP THE FAST WINDS ALOFT AND CAUSE SOUTHWEST TO WEST SURFACE WINDS TO GUST TO 25-30 KTS THROUGH 22Z. FLIGHT CONDITIONS SHOULD BE MAINLY VFR THROUGH 06Z, DESPITE PASSAGE OF FRONTAL BAND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS 14Z-18Z, AS HAVE TOO LOW CONFIDENCE TO MENTION. TIMING OF SHOWERS HAS BEEN BASED ON RECENT WRF-NMM AND HRRR MODEL OUTPUT. COLD POOL STRATOCUMULUS LATE TONIGHT INTO THURSDAY MORNING MAY PROMOTE A PERIOD OF MVFR CEILINGS. OUTLOOK...THURSDAY THROUGH SUNDAY... VFR THURSDAY AFTERNOON INTO FRIDAY. RESTRICTIONS THEN POSSIBLE DUE TO SHOWERS FROM A LOW PRESSURE SYSTEM PASSAGE FRIDAY NIGHT INTO SATURDAY, AND LINGERING COLD POOL CLOUDS SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
646 AM EDT WED MAR 28 2012 .SYNOPSIS... A COLD FRONT WILL BRING SHOWERS WITH THE CHANCE OF THUNDERSTORMS TO THE UPPER OHIO VALLEY REGION TODAY. SEASONABLY COOL WEATHER WILL FOLLOW FOR THURSDAY...BUT LOOK FOR INCREASED RAIN CHANCES AGAIN ON FRIDAY AS LOW PRESSURE APPROACHES THE AREA. && .NEAR TERM /THROUGH TONIGHT/... HAVE DECIDED TO EXPAND THE SPC SLIGHT RISK AREA A FEW COUNTIES NORTHWARD TO INCLUDE GARRETT COUNTY AND THE NORTHERN WEST VIRGINIA ZONES EXCLUDING THE PANHANDLE. SHOULD THUNDERSTORM SUPPORT SURVIVE INTO THE AFTERNOON AS FORECAST...DAMAGING WIND GUSTS WILL BE POSSIBLE IN THE DEEPENING MIXING LAYER. THIS MENTION WAS INCLUDED IN THE HAZARDOUS WEATHER OUTLOOK. PREVIOUS... LOW PRESSURE MOVING ACROSS THE NORTHERN LAKES WILL PULL A COLD FRONT ACROSS THE UPPER OHIO REGION TODAY. STRONG WARM ADVECTION IN ADVANCE OF THE LOW HAS DEVELOPED A SHALLOW INVERSION AND WILL INITIALLY CAP THE BOUNDARY LAYER. HOWEVER...SUFFICIENT FUEL/INSTABILITY IS INDICATED FOR DEVELOPMENT OF SOME ELEVATED SHOWERS/POSSIBLE THUNDERSTORMS THIS MORNING...WHICH SHOULD BECOME MORE SURFACE BASED AS THE FRONT AND THE DAY PROGRESS. OVERALL SEVERE POTENTIAL REMAINS LOW DESPITE FAVORABLE DEEP LAYER SHEAR WITH LIMITATIONS IMPOSED BY A LACK OF INSTABILITY. MODELS ARE IN GENERAL AGREEMENT IN MORE RAPID PASSAGE OF THE FRONT THAN PREVIOUSLY DEPICTED...SO ADJUSTMENTS THIS MORNING FEATURE FADING PRECIP PROBABILITIES DURING THE AFTERNOON. ALSO OF INTEREST FOR THE AFTERNOON IS THE AFOREMENTIONED STRONG WIND FIELD IN CONJUNCTION WITH THE STEEPENING LOW LAPSE RATE AS DISPLAYED VIA MODEL SOUNDINGS. WIND GUSTS HAVE THUS BEEN INCREASED...BUT ARE EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS. COLDER AIR IS PROJECTED TO ADVECT OFF THE LAKES TONIGHT...AND LOW INVERSION LEVELS SHOULD PRECLUDE MUCH THE WAY OF SHOWERS. SMALL PRECIP PROBABILITIES WERE TWEAKED TO FAVOR AREAS IN LEE OF THE LAKES AND THE RIDGES. PROJECTED TEMPERATURE PROFILE ALSO IS INDICATIVE OF SOME FROZEN PRECIP OVER NORTHERN COUNTIES...SNOW SHOWER MENTION WAS THUS ADDED. NEAR TERM TEMPERATURES WERE FORECAST USING TWEAKED SREF MEANS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... BUILDING HIGH PRESSURE SHOULD SNUFF ANY LINGERING SHOWERS BY MIDDAY THURSDAY...AND CONTINUED COLD ADVECTION SHOULD HOLD TEMPERATURES A FEW DEGREES BELOW THE SEASONAL NORMALS. THE SURFACE HIGH PRESSURE AXIS IS NAM/GFS FORECAST TO SLIDE ACROSS THE UPPER OHIO ON THURSDAY NIGHT...AND THE AIRMASS WILL BE PLENTY DRY FOR A PERIOD OF RADIATIONAL COOLING BEFORE WARM...MOIST ADVECTION RESUMES IN ADVANCE OF MIDWESTERN LOW PRESSURE. ANOTHER FREEZE IS THUS FORECAST...BUT DURATION/MAGNITUDE LOOKS TO BE LIMITED AS MID LEVEL CLOUDINESS INCREASES. ANOTHER SHORTWAVE IS FORECAST FOR A FRIDAY APPROACH AND SATURDAY EXIT...HENCE CHANCE POPS WERE MAINTAINED FOR THE CLOSE OF THE WORK WEEK...FOLLOWED BY DIMINISHED NUMBERS INTO THE WEEKEND. SHORT TERM TEMPERATURES SHOULD AVERAGE OUT FAIRLY CLOSE TO NORMAL AND WERE FORECAST USING A BLEND OF SREF AND GFS MOS. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... PROGRESSIVE PATTERN IS GFS/ECMWF DEPICTED FOR THE LONG TERM PERIOD AND AS SENSIBLE WEATHER WILL THUS BE SHORTWAVE DEPENDENT...FORECAST WILL GENERALLY BE OF PERSISTENCE AND ALTERATIONS MINIMAL THIS MORNING. WITH THE JET PROJECTED TO MEANDER OVER...OR NORTH OF THE GREAT LAKES...TEMPERATURES WERE FORECAST ABOVE THE SEASONAL AVERAGES USING TWEAKED HPC GUIDANCE. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... MAIN AVIATION CONCERN THROUGH 14Z WILL BE LOW LEVEL WIND SHEAR. RECENT NAM MODEL PROFILES SHOW A VERY STRONG AND SHALLOW SURFACE INVERSION THIS MORNING, WITH BASE 1 KFT AGL, HAVING SURFACE WINDS FROM THE SOUTH AT 5-10 KTS. RADAR VERTICAL WIND PROFILES AND NAM MODEL PROFILES SHOW WINDS FROM THE SOUTHWEST AND WEST 35-50 KTS IN THE LAYER 1-2 KFT AGL WILL CONTINUE TODAY. BLEND OF HIGH RESOLUTION MODEL OUTPUT SHOW VERTICAL MIXING, ACCOMPANYING THE COLD FRONTAL PASSAGE 14Z-18Z, DEEPENING THE SURFACE LAYER WHICH WILL THEN TAP THE FAST WINDS ALOFT AND CAUSE SOUTHWEST TO WEST SURFACE WINDS TO GUST TO 25-30 KTS THROUGH 22Z. FLIGHT CONDITIONS SHOULD BE MAINLY VFR THROUGH 06Z, DESPITE PASSAGE OF FRONTAL BAND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS 14Z-18Z, AS HAVE TOO LOW CONFIDENCE TO MENTION. TIMING OF SHOWERS HAS BEEN BASED ON RECENT WRF-NMM AND HRRR MODEL OUTPUT. COLD POOL STRATOCUMULUS LATE TONIGHT INTO THURSDAY MORNING MAY PROMOTE A PERIOD OF MVFR CEILINGS. OUTLOOK...THURSDAY THROUGH SUNDAY... VFR THURSDAY AFTERNOON INTO FRIDAY. RESTRICTIONS THEN POSSIBLE DUE TO SHOWERS FROM A LOW PRESSURE SYSTEM PASSAGE FRIDAY NIGHT INTO SATURDAY, AND LINGERING COLD POOL CLOUDS SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
929 AM CDT WED MAR 28 2012 .UPDATE... ISSUED AT 915 AM CDT WED MAR 28 2012 WEAK COLD FRONT/WIND SHIFT IS STALLING AND CURRENTLY STRETCHES FROM KDMO-KUUV-KBLV-KSLO. THIS WAS A TAD FURTHER NORTH THAN GRIDDED DATABASE REFLECTED SO HAVE ADJUSTED FORECAST A BIT TO ACCOUNT FOR THIS LOCATION. EXPECT TEMPERATURES WILL BE QUITE WARM ALONG AND SOUTH OF THIS FRONT WITH FAVORABLE WESTERLY WIND AND DEEP MIXING. HAVE MAINTAINED SLIGHT CHANCE POPS FOR THUNDERSTORMS THIS AFTERNOON ALONG AND SOUTH OF THE BOUNDARY...BUT BELIEVE BEST CHANCES WILL REMAIN TO OUR WEST WHERE HRRR IS SHOWING CONVECTIVE INITIATION FROM ST. JOSEPH TO KANSAS CITY BY 00Z. CVKING && .SHORT TERM... ISSUED AT 349 AM CDT WED MAR 28 2012 (TODAY-TONIGHT) FOCUS THRU THE PERIOD WILL BE TEMPS TODAY AND POPS TONIGHT. CDFNT CONTINUES TO MOVE S...JUST ENTERING THE NRN PORTIONS OF THE CWA AS OF 08Z. HAVE KEPT SLIGHT CHANCE POPS GOING FOR A COUPLE OF HRS AFTER SUNRISE TO ACCOUNT FOR ANY SURPRISE TSRA. IF ANYTHING DOES FORM...COVERAGE SHUD BE ISOD. EVEN WITH THE CDFNT PUSHING THRU MUCH OF THE CWA...EXPECT DEEP MIXING TO OCCUR BEHIND THE FNT WITH TEMPS REACHING THE UPPER 70S TO LOWER 80S. WITH MIXING EXPECTED TO REACH NEARLY 800MB...HAVE TRENDED ABOVE MOS FOR TODAY. THE FNT SHUD STALL ACROSS THE SRN HALF OF THE CWA...THO THERE IS SOME UNCERTAINTY JUST HOW FAR S IT WILL REACH BEFORE STALLING. WITH INCREASED SFC CONVERGENCE AND SOME FORCING THRU THE LOWER LEVELS...EXPECT TSRA TO DEVELOP ALONG THE FNT THIS AFTERNOON. WITH THESE BEING DIURNALLY DRIVEN...SHUD DISSIPATE DURING THE EVENING AS FORCING BEGINS TO REFOCUS FURTHER W ACROSS KS. THIS SHUD BE THE GENESIS REGION FOR AN MCS. EXPECT TSRA TO DEVELOP THIS AFTERNOON ACROSS THE ERN HALF OF KS JUST AHEAD OF A WEAK SFC WAVE. MDLS DIFFER WHERE THIS WILL OCCUR WHICH WILL HAVE DRAMATIC IMPACTS ON THE FCST FOR TONIGHT. BELIEVE MCS ACTIVITY WILL TRACK SE ALONG THE FNT AND SHUD REMAIN W OF THE CWA. IN THE WAKE OF THIS COMPLEX...EXPECT H85 FLOW TO BECOME MORE WLY AND INTERSECT THE H85 FNT ALLOWING A SECOND ROUND OF TSRA TO FORM. THESE TSRA ARE EXPECTED TO REACH CNTL MO AROUND/JUST BEFORE SUNRISE THURS. SOME UNCERTAINTY IF THESE TSRA WILL HAVE SEVERE POTENTIAL AS MDLS DEPICT SOMEWHAT MEAGER MID LEVEL LAPSE RATES. TILLY && .LONG TERM... ISSUED AT 409 AM CDT WED MAR 28 2012 (THURSDAY-TUESDAY) BEGINNING OF PERIOD WILL DEPEND UPON WHAT OCCURS OVERNIGHT AS DISCUSSED ABOVE. MDLS STILL DIFFER REGARDING WHERE PRECIP WILL BE ONGOING AT THE BEGINNING OF THE PERIOD. OVERALL...BELIEVE PRECIP SHUD DIMINISH DURING THE MORNING AND REFOCUS FURTHER W AHEAD OF A DEVELOPING SFC LOW ASSOC WITH A DEEPER UPPER TROF. MAIN QUESTION WILL BE HOW FAR E THE ELEVATED TSRA GET DURING THE MORNING BEFORE DISSIPATING. KEPT POPS FOR THURS AFTERNOON ALONG THE SFC FNT DURING THE AFTERNOON WHERE SFC CONVERGENCE SHUD HELP INITIATE TSRA. INCREASED POPS FOR THURS NIGHT AS THE SYSTEM PUSHES THRU THE REGION...BUT KEPT LINGERING POPS INTO FRI TO ACCOUNT FOR TIMING DIFFERENCES IN MDLS. THIS SYSTEM SHUD BRING SOMEWHAT COOLER TEMPS FOR FRI AND SAT...THO STILL WELL ABOVE SEASONAL AVG. FOR THE EXTD...MAIN FOCUS WILL BE TEMPS AS NOT MUCH EXPECTED IN THE WAY OF PRECIP CHANCES. WITH RETURN FLOW STARTING ALREADY BY SAT MORNING...TEMPS SHUD REBOUND QUICKLY. STARTED A WARMER TREND SAT AND SUN...THO DID NOT GO AS WARM AS THE MEX MOS WUD SUGGEST WITH NEAR RECORD TEMPS FOR CNTL MO ON SAT AND THE ENTIRE CWA FOR SUN. MDLS HAVE SPED UP TIMING OF FROPA ON SUN NIGHT INTO MON WITH THE GFS AS A FAST OUTLIER. HAVE THEREFORE TRENDED TWD THE SLOWER ECMWF/GEM. KEPT LOW POPS FOR FROPA. THE GEM/GFS DO SUGGEST SOME PRECIP WILL BE POSSIBLE...THO TIMING DIFFERS. BEHIND THIS SYSTEM...MDLS ARE IN FAIRLY GOOD AGREEMENT SUGGESTING MUCH COOLER TEMPS WITH HIGHS ON ON TUES ONLY A FEW DEGREES ABOVE AVG. TILLY && .AVIATION... ISSUED AT 635 AM CDT WED MAR 28 2012 COLD FRONT APPROACHING COU-DEC LINE ATTM...WITH RADAR IMAGERY ONLY INDICATING SPORATIC FEEBLE ATTEMPTS AT PRECIP DEVELOPMENT IN MODEST POCKET OF RESDIUAL INSTABILITY AHEAD OF THE BOUNDARY. WITH FRONT PUSHING S OF THE STL AREA OVER THE NEXT FEW HOURS...ANY REDEVELOPMENT THAT OCCURS NEAR THE BOUNDARY LATER THIS MORNING OR THIS AFTERNOON WILL BE S OF ALL TAF LOCATIONS. AMS N OF THE FRONT IS QUITE DRY...SO EXPECTING LITTLE IF ANY CLOUDINESS TODAY. THUNDERSTORMS SHOULD REDEVELOP OVER E KS AND W MO TONIGHT AS WARM ADVECTION INTERACTS WITH STALLED BOUNDARY. GETTING THE IMPRESSION THERE COULD BE TWO WAVES OF STORMS...THE FIRST THAT FORMS LATER THIS AFTERNOON/EARLY THIS EVENING THAT WILL TRACK NEAR THE SURFACE FRONT ACROSS S MO...AND THEN A MORE ELEVATED BATCH OF STORMS THAT WOULD IMPACT COU DURING THE PREDAWN HOURS. SPECIFICS FOR KSTL... FRONTAL PASSAGE WILL OCCUR IN THE NEXT FEW HOURS. ONCE WIND SHIFT OCCURS...EXPECT A GRADUAL VEERING OF THE WIND TO A NE DIRECTION BY EARLY EVENING WITH SPEEDS AOB 8KTS. OUTSIDE OF A FEW SCATTERED MID CLOUDS OVER THE NEXT FEW HOURS...LITTLE IF ANY CLOUDINESS EXPECTED TODAY. ELEVATED STORMS MENTIONED IN GENERAL DISCUSSION SHOULD REMAIN WELL WEST OF STL THROUGH THURSDAY MORNING. TRUETT && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1042 AM CDT WED MAR 28 2012 .DISCUSSION... CHALLENGES TODAY ARE CLOUDS AND TEMPERATURES. 15 UTC SATELLITE LOOP SHOWS LOW STRATUS DECK FROM SOUTHEAST SASKATCHEWAN TO WEST- CENTRAL MN. CLOUDS ARE MORE OR LESS STATIONARY AND FLOW ALOFT WEAKENS TODAY AS SURFACE RIDGE AXIS MOVES ACROSS THE FORECAST AREA. RUC 925 HPA RH APPEARS TO HAVE BEST HANDLE ON CURRENT CONDITIONS AND HINTS THAT CLOUDS WILL BE VERY SLOW TO DISSIPATE THROUGH THE DAY. THERE ARE SOME BREAKS IN THE CLOUDS ACROSS NORTHEAST ND AND NORTHWEST MN...BUT CONVECTIVE TEMPERATURES IN THE MID 40S SUGGEST SOME AFTERNOON THERMAL CUMULUS. OVERALL...EXPECT MOSTLY CLOUDY CONDITIONS WITH SOME SUN BY LATE THIS AFTERNOON... ESPECIALLY ACROSS THE NORTHERN FORECAST AREA. WITH BKN-OVC SKY COVER AND NEAR NEUTRAL LOW-LEVEL TEMPERATURE ADVECTION...TEMPERATURES WILL STRUGGLE TO REACH PREVIOUS FORECAST AFTERNOON HIGHS. DROPPED HIGHS 2 TO 3 DEGREES ACROSS THE SOUTH... BUT THIS MAY NOT BE ENOUGH IF CLOUD COVER HOLDS STEADY. DID INCREASE VALUES A DEGREE OR TWO ACROSS THE NORTH WHERE THERE IS SOME SUN THIS MORNING. WILL GO WITH HIGHS IN THE MID 40S TO NEAR 50 DEGREES ACROSS THE SOUTHERN VALLEY...BUT WOULD NOT BE SURPRISED IF SOME AREAS ONLY REACH THE LOW 40S. && .AVIATION... MVFR/IFR CEILINGS WILL BE SLOW TO ERODE TODAY AT ALL TAF SITES GIVEN WEAK FLOW ALOFT AND SURFACE HIGH PRESSURE. LIGHT NORTH-NORTHEAST WIND WILL GRADUALLY SHIFT TO THE EAST LATER THIS EVENING. && .PREV DISCUSSION... /ISSUED 430 AM CDT WED MAR 28 2012/ SHORT TERM...TODAY THROUGH FRIDAY NIGHT. PROGRESSIVE UPPER AIR PATTERN IS FORECAST FOR THE NORTHERN PLAINS. NORTHWEST FLOW ALOFT WAS OVER THE AREA. UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES WILL MOVE ACROSS THE AREA TONIGHT. THEREAFTER FLOW ALOFT BECOMES ZONAL. WATER VAPOR LOOP INDICATED A PARADE OF SHORT WAVES UPSTREAM. ONE SHORT WAS OVER THE AREA. WILL ADD LOW POPS OVER NORTHEAST ZONES THIS MORNING. INL OBSERVED SOUNDING INDICATED FAIRLY DEEP LOW LEVEL MOISTURE UP TO 775 HPA. EXPECT CLOUDS FOR MUCH OF THE DAY. CLEARING MOST LIKELY OVER SOUTH AND WEST ZONES THIS AFTERNOON. AN UNSETTLED PERIOD IS EXPECTED FOR THE NEXT 84 HOURS. LOW LEVEL JET TO INCREASE LATER TONIGHT. WILL ADD LOW POPS AFTER MIDNIGHT. SHORT WAVE OFF THE WEST COAST WILL MOVE THROUGH THU/THU NIGHT. POPS WERE TWEAKED FOR THU AND THU NIGHT. NO CHANGE TO POPS FOR FRI IN THE NORTH. LONG TERM...[SATURDAY-TUESDAY] ALL THE DETERMINISTIC MODELS HAVE A FAIRLY ACTIVE PATTERN FOR THE PERIOD...BUT THERE ARE SOME SIGNIFICANT DIFFERENCES IN PLACEMENT AND TIMING OF VARIOUS SHORTWAVES COMING THROUGH. TEMPERATURES CONTINUE TO LOOK MILD THROUGH THE WEEKEND AS THE GFS...ECMWF...AND GEM ALL HAVE 850MB TEMPS WELL INTO THE TEENS C. THE DIFFERENCES START WITH THE TIMING OF THE NEXT SHORTWAVE COMING IN SUNDAY NIGHT/MONDAY...WITH THE GFS MUCH MORE PROGRESSIVE WITH THE SYSTEM THAN THE OTHER MODELS. THERE IS FAIRLY GOOD AGREEMENT ON SOME COLDER TEMPS COMING DOWN FOR THE EARLY PART OF NEXT WEEK BEHIND THE SHORTWAVE...BUT AS FAR AS PRECIP GOES TIMING OF ANYTHING IS VERY MUCH UP IN THE AIR. THE GFS BRINGS ANOTHER SHORTWAVE INTO WESTERN ND BY TUESDAY WHILE THE ECMWF KEEPS THE CWA UNDER NORTHWESTERLY FLOW. ENSEMBLE SPREAD BECOMES VERY HIGH AS EARLY AS SUNDAYS SYSTEM...SO CONFIDENCE IN ANY ONE SOLUTION IS VERY LOW. THUS...CONTINUED TO KEEP THE BLENDED FORECAST...WITH SOME MINOR TWEAKS TO AGREE A BIT BETTER WITH THE NEIGHBORS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ ROGERS/HOPPES
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1017 AM EDT WED MAR 28 2012 .SYNOPSIS... A COLD FRONT WILL PASS SOUTHEAST THROUGH THE REGION TODAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...LEADING TO TRANQUIL CONDITIONS ON THURSDAY. ON FRIDAY...A LOW PRESSURE SYSTEM WILL DEVELOP IN THE CENTRAL PLAINS AND MOVE INTO THE REGION...BRINGING THE NEXT CHANCE OF PRECIPITATION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... GOING FORECAST IN GOOD SHAPE AND ONLY MINOR TWEAKS NEEDED THIS MORNING. 28.12Z KILN RAOB INDICATED IN EXCESS OF 1000 J/KG OF ELEVATED INSTABILITY FOR PARCELS LIFTED FROM ABOUT 900MB...AND NO DOUBT SOME OF THIS BEING REALIZED WITH SHOWERS/SCT STORMS SEEN ON KILN WSR-88D THIS MORNING. FORCING FOR ASCENT THUS FAR DRIVEN BY LOW LEVEL THETA-E ADVECTION JUST ABOVE THE INVERSION...AS SFC COLD FRONT ATTENDANT TO THE GREAT LAKES SHORTWAVE TROUGH IS STILL BACK IN NWRN OH INTO SWRN IND. FRONT SHOULD PASS QUICKLY SOUTHEAST THROUGH THE ILN FORECAST AREA THROUGH 6 PM...AND THERE IS REMARKABLE AGREEMENT FROM THE CONVECTION ALLOWING MODELS /NSSL-WRF...NCEP ARW WRF...AND HRRR/ THAT CONVECTION WILL SLOWLY DEVELOP THROUGH THE DAY ALONG/JUST AHEAD OF THE FRONT...PEAKING IN THE FAR SOUTHERN/SERN FORECAST AREA BETWEEN 2PM AND 5 PM. BEST CHANCE FOR A STRONGER STORM IN THE LOWER SCIOTO VALLEY AND NERN KY...WHERE BEST INSTABILITY /MLCAPE AROUND 1000 J/KG/ WILL HAVE BUILT. 28.12Z RUC FORECAST SOUNDINGS AT PMH VALID 20Z INDICATE DEEP WLY TROPOSPHERIC FLOW...AND STRONG...SUGGESTING SOME STORM ORGANIZATION IS LIKELY BUT NOT DIRECTIONAL SHEAR IS DEFINITELY LACKING. WIND/HAIL THE MAIN THREATS IN THE FAR SOUTH. BACK TO THE N/W BEHIND THE FRONT IN WCNTL/CNTL OH...AMPLE SUNSHINE AND CRASHING DEWPOINTS/COLD ADVECTION WILL BRING WINDS UP IN THE MID TO LATE AFTERNOON WHICH SHOULD GET SOME GUSTS ABOVE 30KTS IN THE WIND PRONE AREAS. LAPSE RATES ON FCST SOUNDINGS ARE STEEP WITH A STRONG FLOW IN THE BOUNDARY LAYER. CHANGES THIS MORNING TO FORECAST TO BUMP WINDS UP JUST A BIT IN THE NORTH...AND BUMP RAIN CHANCES IN THE SOUTH UP A BIT. OTHERWISE FCST IN GOOD SHAPE. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... HIGH PRESSURE WILL FILL IN BEHIND THE COLD FRONT FOR TONIGHT AND THURSDAY...AS NORTHWEST FLOW CONTINUES ALOFT. THE COOL DOWN BEHIND THE FRONT WILL RESULT IN A 10-15 DEGREE DROP FROM WEDNESDAY TO THURSDAY...WITH WARM ADVECTION NOT REALLY KICKING BACK IN UNTIL THURSDAY NIGHT. THIS WILL LEAD TO TWO NIGHTS ON THE COOL SIDE OF THINGS. TEMPERATURES IN THE FAR NORTH ON WEDNESDAY NIGHT APPEAR THAT THEY MAY BE COLD ENOUGH TO SUPPORT SOME FROST...ALTHOUGH A LACK OF MOISTURE MAY PRECLUDE THIS FROM OCCURRING. CONDITIONS FOR A FREEZE IN CENTRAL OHIO ON THURSDAY NIGHT LOOK SLIGHTLY LESS FAVORABLE THAN THEY DID PREVIOUSLY (WITH A BUMP FORWARD IN TIMING ON THE NEXT WEATHER SYSTEM)...BUT THERE IS CERTAINLY STILL ENOUGH OF A CHANCE TO KEEP AN HWO MENTION. MODEL GUIDANCE REMAINS IN POOR AGREEMENT FOR THE SYSTEM ON FRIDAY AND SATURDAY. OF CONCERN IS THE FACT THAT THE ECMWF HAS BEEN STEADY IN ITS SLOWER SOLUTION WITH A DEEPER MID-LEVEL TROUGH...WHILE THE GFS AND NAM ARE BOTH IN REMARKABLE AGREEMENT ON A FASTER PROGRESSION AND STRONGER SURFACE LOW. THUS...CONFIDENCE IN THE FORECAST FROM FRIDAY AND BEYOND IS BELOW AVERAGE. PRECIPITATION OVER THE FORECAST AREA IS CERTAIN TO OCCUR DURING THIS TIME FRAME...AND THE OVERALL TREND HAS BEEN SLIGHTLY SPED UP IN THIS FORECAST PACKAGE. ASIDE FROM THE PRECIPITATION CHANCES...THE TRACK AND STRENGTH OF THE SURFACE LOW WILL ALSO HAVE MAJOR IMPLICATIONS ON FRONTS...TEMPERATURES...AND ANY POTENTIAL SEVERE THREAT. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... TEMPERATURES WILL BE ABOVE NORMAL WITH HIGHS IN THE 60S AND 70S. THE COOLEST DAY LOOKS TO BE SATURDAY WITH LOW TO MID 60S FORECAST DUE TO COLD ADVECTION AND CLOUDS BEHIND THE LOW. THE WARMEST READINGS INTO THE MID 70S ARE FORECAST FOR MONDAY WHEN ADVECTION OCCURS AHEAD OF THE COLD FRONT. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... A COLD FRONT WILL DROP SE ACROSS THE TAF SITES BETWEEN 16Z AND 20Z. ALTHOUGH THERE WILL BE INCREASING INSTABILITY AHEAD OF THE FRONT...LOW LEVEL CONVERGENCE AND DYNAMICS DO NOT LOOK ALL THAT IMPRESSIVE FOR THIS MORNING. AS A RESULT...HAVE ONLY EMPLOYED A VCSH OR A VCTS AT THE TAF SITES BEFORE FRONTAL PASSAGE. MUCH DRIER AIR WILL ADVECT IN BEHIND THE FRONT WILL ONLY SOME SCATTERED CIRRUS EXPECTED THIS AFTERNOON. OF BIGGER CONCERN WILL BE THE GUSTY WEST TO NORTHWEST WINDS OF 15 TO 20 KNOTS WITH GUSTS AROUND 30 KNOTS. FOR TONIGHT...HIGH PRESSURE WILL BUILD SOUTHWARD INTO THE WESTERN GREAT LAKES AND OHIO VALLEY. SKIES WILL BE MAINLY CLEAR WITH DIMINISHING WINDS EXPECTED AFTER SUNSET. OUTLOOK...THUNDERSTORMS POSSIBLE FRIDAY INTO SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...BINAU SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
139 PM EDT WED MAR 28 2012 .SYNOPSIS... A LOW PRESSURE WILL MOVES ACROSS NEW ENGLAND LATE TODAY INTO THURSDAY BRINGING A CHANCE OF SHOWERS. COOL AND DRY WEATHER FOLLOWS FRIDAY...WITH ANOTHER LOW PRESSURE LIKELY TO MOVE SOUTH OF OUR REGION DURING THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 130 PM UPDATE... HRRR MODEL IS DOING A GOOD JOB WITH CURRENT AREA OF SHOWERS WHICH HAVE MOVED TO THE S COAST AS EXPECTED ASSOCD WITH THE LOW LEVEL JET. STILL SOME LIGHTNING STRIKES ACROSS COASTAL CT AND THE RI COASTAL WATERS BUT GREATER INSTABILITY AND MID LEVEL LAPSE RATES ARE CONFINED FURTHER S OVER THE MID ATLC REGION. HRRR MOVES THESE SHOWERS S OF THE COAST 18-20Z AND CANT RULE OUT A BRIEF TSTM ALONG THE COAST AND ADJACENT WATERS AS THE SHOWERS MOVE THROUGH. CLEARING HAS DEVELOPED ACROSS CENTRAL NY AND MAY SEE SOME SUNSHINE THIS AFTERNOON...ESPECIALLY SW ZONES. HRRR IS SHOWING A FEW SHOWERS DEVELOPING ACROSS W ZONES LATE TODAY ASSOCD WITH SOME LEFTOVER ELEVATED INSTABILITY BUT STRONG MID LEVEL DRYING SHOULD LIMIT CONVECTIVE POTENTIAL. TEMPS ARE TRICKY TODAY AS WARM FRONT WILL BE APPROACHING FROM THE SW BUT WILL LIKELY REMAIN TO THE S OR POSSIBLY GET CLOSE TO HFD- WST LINE. TEMPS ACROSS N ZONES SHOULD REMAIN IN THE 40S...BUT RISING INTO THE 50S ELSEWHERE. GUSTY SW WINDS WILL CONTINUE NEAR THE S COAST ASSOCD WITH THE LOW LEVEL JET. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... BOTH THE NAM AND GFS EXHIBIT EXCELLENT CONVECTIVE INDICES FOR THIS TIME OF YEAR. THE PROBLEM IS THE SUBSTANTIAL INVERSION WITH A BASE AROUND 900 MB OR LOWER. NAM IS SLIGHTLY MORE AGGRESSIVE ADVERTISING ELEVATED INSTABILITY ABOVE THIS INVERSION...BUT IT IS SHORT-LIVED AND SHALLOW. KEPT THUNDER OUT OF THE FORECAST FOR NOW FOR THIS EVENING. THIS POSSIBILITY WILL NEED TO BE WATCHED THOUGH. THIS LOW PRESSURE AND ITS ASSOCIATED FRONTS EXPECTED TO MOVE OFFSHORE WEDNESDAY NIGHT. HIGH PRESSURE OVER EASTERN CANADA STARTS TO EXERT ITS INFLUENCE ON OUR WEATHER...BUT IT IS STILL FAR AWAY MOST OF THURSDAY. EXPECTING LOW CLOUDS AND LINGERING SHOWERS ACROSS EASTERN SOUTHERN NEW ENGLAND AS A RESULT. A BLEND OF MAV/MET TEMPERATURES LOOKED REASONABLE. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * DRY FOR THURS NIGHT INTO FRI NIGHT * A WEATHER DISTURBANCE LOOKS TO STAY S OF THE REGION DURING THE WEEKEND OVERVIEW... FCST GUIDANCE CONSISTENCY FOR THE WEEKEND SYS HAS GENERALLY TRENDED WITH A SOUTH COAST STORM...YET THE SPECIFICS IN BOTH TIMING AND EVOLUTION ARE QUITE VARIED. SUBSEQUENTLY...LOW CONFIDENCE PREVAILS FOR THE WEEKEND ONWARD. MASS FIELDS OF THE 28/0Z PACKAGE OF THE GFS/NAM ARE BROUGHT INTO QUESTION...SUCH A WEAK TROF AXIS WITH ATTENDANT SHRTWV ENERGY AND LESSER JET DYNAMICS PER GFS YIELDS A ROBUST AND STRONG SYS? HAVE GREATER CONFIDENCE IN THE 28/0Z CANADIAN/ECMWF PACKAGE WHICH EXHIBITS MASS FIELDS ONE WOULD EXPECT WITH THE FCST MODEST S COAST STORM. NOT ABSOLUTELY SURE ON THE PROGRESSIVENESS OF THE SYS. AO IS FCST TO BE POSITIVE WITH THE NAO NEAR NEUTRAL...SO ITS NOT A CLEAR CUT PROGRESSIVE PATTERN OVER THE N ATLANTIC. THERE IS A STRONG LOW ROTATING OVER ERN CANADA THAT COULD BE PROBLEMATIC. A LOT OF QUESTIONS ARE STILL ON THE TABLE...AND THE ASSOC PACIFIC ENERGY IS JUST COMING ONSHORE OF THE WRN CONUS. AM EXPECTING THAT FCST GUIDANCE WILL EXHIBIT BETTER AGREEMENT WITH THE NEXT MDL RUN OR TWO. OTHERWISE THE FCST SPECIFICS ARE TRULY SPECULATIVE. THURSDAY NIGHT... SFC HIGH PRES RIDGE BUILDING EWD OUT OF CENTRAL CANADA WITH NW FLOW AND DRIER AIR. NLY COMPONENT OF FLOW INITIALLY WILL ALLOW FOR CONTINUED SHOWER ACTIVITY ALONG THE E SHORE AND ADJACENT WATERS /SST TEMPS AROUND +7C WITH H85 TEMPS AROUND -8C...A DIFFERENCE BETWEEN 10-13C WARRANT CLOUDS AND PSBL SHOWERS/. YET ACTIVITY SHOULD BE SHORT-LIVED AND PUSH EWD AS SFC WINDS EXHIBIT A MORE WLY COMPONENT WITH TIME. SHOULD REMAIN MOSTLY CLEAR...BUT WITH NW WINDS REMAINING MODEST...NOT THINKING A GOOD NOCTURNAL COOLING SCENARIO. MIN TEMPS AROUND THE LOW 30S. MAIN COLD POOL ALOFT SHOULD BE ACROSS NEW ENGLAND BY FRI MORN. FRIDAY... SFC HIGH PRES RIDGE IN CONTROL WITH NW FLOW WEAKENING THRU THE DAY. MOSTLY CLEAR CONDITIONS SHOULD ALLOW FOR LOW-LVL MIXING OF DRIER AIR TO THE SFC. LOOKING LIKE A DAY WHERE CONDITIONS MAY BE FAVORABLE FOR FIRE WX SPREAD...YET LESSER WINDS WILL KEEP CONDITIONS FROM REACHING RED FLAG CRITERIA. WILL KEEP THE PD DRY...WITH INCREASING MID LVL CLOUDS AHEAD OF AN APPROACHING TROF SYS THRU THE ZONAL LONGWAVE PATTERN. HIGHS AROUND THE UPR 40S WITH LOW 50S ALONG THE SRN TIER OF NEW ENGLAND. FRIDAY NGT INTO THE WEEKEND... AS EMPHASIZED IN THE OVERVIEW...AM MORE INCLINED TO GO WITH THE 28/0Z CANADIAN/ECMWF PACKAGE AS THE FCST MASS FIELDS ARE MORE IN-LINE WITH THE SFC OUTCOMES. IN FURTHER DETAIL...DEPENDING UPON THE EVOLUTION AND PROXIMITY OF THE SFC LOW AND ATTENDANT MID-LVL TROF WITH NEW ENGLAND...THERE ARE SOME NOTABLE DETAILS... * ISENTROPIC UPGLIDE OF A WARM MOIST CONVEYOR BELT IS AMPLIFIED ALONG WITH SW MID LVL FLOW IN RESPONSE TO H3 JET LVL DYNAMICS AND DIV ALOFT * LIFT OCCURS AHEAD OF THE SYS /SSW TO NE/ ACROSS THE SFC-H8 WARM FRNT...THE STRONGEST OF WHICH IS ADJACENT AND N OF THE WARM FRNT AROUND H8 WHERE ISENTROPIC UPGLIDE COUPLES WITH UPR LVL DIFLUENCE PROMOTING DEEP LYR LIFT /SO AHEAD AND N OF THE SYS THERE WILL LIKELY BE SOME GOOD MID-LVL FRONTOGENETICAL LIFT AND UPR LVL DIV TO PROMOTE BANDING OF PRECIP/ * CONSEQUENTIALLY THERE WILL LIKELY BE AN OVERRUNNING WARM TONGUE OF AIR OVER UNDERCUTTING SFC COLD AIR /AND NLY FLOW/ FROM THE COLD HIGH PRES OUT OF CENTRAL CANADA...MAKING FOR SOME ISSUES WITH PRECIP TYPE SO AN OVERRUNNING SITUATION ACROSS S NEW ENGLAND IS POSSIBLE...YET AGAIN THE TIMING /DURING THE DAY OR NIGHT?/ AND PROXIMITY OF THE SFC LOW /CLOSER TO S NEW ENGLAND WOULD PUSH GREATER PRECIP CHCS AND PSBL WINTRY WX INTO INTERIOR NEW ENGLAND...OR IT MAY REMAIN OUTRIGHT DRY/ ARE KEY FOR THE FCST. THE FCST AS IT STANDS RIGHT NOW IS A BROAD BLEND OF FCST GUIDANCE WITH HEAVIER WEIGHT ON THE 28/0Z ECMWF/CANADIAN SOLN OVER MOST OF THE WEEKEND AS SOLNS DIFFER ON THE TIMING OF THE STORM. FCST WILL BE REFINED AS WE GET CLOSER IN TIME. CONFIDENCE AS IT STANDS IS THAT A SYS IS EXPECTED TO SWEEP S OF NEW ENGLAND...THAT SEEMS CERTAIN... BUT SPECIFICS ARE VERY UNCERTAIN AS OF NOW. BEYOND THE WEEKEND... WHILE A BRIEF PD OF HIGH PRES IS EXPECTED IN WAKE OF THE STORM...IT APPEARS THE RETURN OF WARM WX IS IN THE CARDS WITH AN ATTENDANT WARM FRNT INTO MIDWEEK. BUT THIS MAY BE SHORT-LIVED AS A COLD FRNT SWEEPS THRU THE RGN TOWARDS THE LATER HALF OF THE WEEK. A FAIRLY UNCERTAIN FCST INTO THE END OF NEXT WEEK. && .AVIATION /17Z WEDNESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT MODERATE...30 PERCENT TO 60 PERCENT HIGH...GREATER THAN 60 PERCENT THROUGH 00Z... MODERATE TO HIGH CONFIDENCE. VFR CIGS WILL CONTINUE WITH AREAS OF MVFR VSBYS IN SHOWERS ALONG THE S COAST THROUGH 19-20Z. SW WIND GUSTS TO 25 KT DEVELOPING ALONG THE S COAST. TONIGHT... MODERATE CONFIDENCE. EXPECT VFR CIGS TO LOWER TO MVFR OVERNIGHT...MAINLY ACROSS N ZONES WHERE A FEW SHOWERS POSSIBLE WHILE REMAINING VFR CLOSER TO THE S COAST. WINDS SHIFTING TO NW LATE TONIGHT. THURSDAY... MODERATE CONFIDENCE. AREAS OF MVFR CIGS IN THE MORNING...ESPECIALLY E OF CT VALLEY. THEN CIGS LIFTING TO VFR IN THE AFTERNOON. A FEW SHOWERS POSSIBLE E NEW ENG. THURSDAY NIGHT... MODERATE TO HIGH CONFIDENCE VFR. KBOS TERMINAL... MODERATE CONFIDENCE IN TAF. MAY SEE A PERIOD OF MVFR CIGS 1500-2500 FT DEVELOPING OVERNIGHT...MAINLY AFTER 06Z AND CONTINUING INTO THE MORNING. THEN LIFTING TO VFR DURING THE AFTERNOON. OUTLOOK...FRIDAY THROUGH SUNDAY... FRIDAY... MODERATE CONFIDENCE VFR. FRIDAY NIGHT INTO THE WEEKEND... LOW CONFIDENCE. STORM WILL SWEEP S OF NEW ENGLAND LENDING TO PSBL MVFR-IFR CIGS AND VSBYS. SPECIFICS DEPEND UPON THE TIMING AND PROXIMITY OF THE SFC LOW WHICH IS UNCERTAIN AS OF NOW. SHOULD SEE INCREASING ELY FLOW IN RESPONSE TO DEEPENING SYS TRACKING S OF NEW ENGLAND...BECOMING NWLY AND REMAINING MODEST AS THE SYS EXITS E. PSBL RAIN/SNOW SHOWERS...MORESO FOR THE S COAST...SO HAVE GREATEST CONFIDENCE IN IMPACTS FOR THE SRN TERMINALS. && .MARINE... ANOTHER PERIOD OF GUSTS TO 25 KT IS LIKELY ACROSS THE SOUTH COASTAL WATERS THIS AFTERNOON AS A LOW-LEVEL JET MOVES EAST ACROSS THE WATERS. EXPANDED THE SCA TO INCLUDE NARRAGNSETT BAY...BUZZARDS BAY AND MVY SOUND. WINDS SHIFT TO THE NW AFTER MIDNIGHT TONIGHT BEHIND A COLD FRONT. OUTLOOK...THURSDAY THROUGH SUNDAY... THURSDAY NIGHT INTO FRIDAY... NW FLOW REMAIN BLUSTERY OVER THE WATERS WITH SCTD RAIN AND PSBL SNOW SHOWERS. SEAS ALONG THE OUTER WATERS TO REMAIN AROUND 5 FT INTO THE LATE FRI PD BY WHICH TIME WINDS AND SEAS SHOULD SUBSIDE. FRIDAY NIGHT INTO THE WEEKEND... STORM SYS IS EXPECTED TO BECOME ORGANIZED AND DEEPEN AS IT PASSES THRU THE MID-ATLANTIC AND OFFSHORE JUST S OF NEW ENGLAND. ELY FLOW WILL INCREASE IN RESPONSE AND SHOULD SEE SEAS BUILD ALONG THE S COAST ACCORDINGLY. NW FLOW IN WAKE OF THE SYS AS IT DEPARTS. A GREAT DEAL OF UNCERTAINTY IN THE FCST AS THE SPECIFICS OF BOTH THE TIMING AND PROXIMITY OF THE SFC LOW TO S NEW ENGLAND ARE STILL IN QUESTION. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ232>234-236. SMALL CRAFT ADVISORY UNTIL NOON EDT THURSDAY FOR ANZ235-237. SMALL CRAFT ADVISORY FROM 2 AM TO 8 PM EDT THURSDAY FOR ANZ250. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR ANZ254. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR ANZ255-256. && $$ SYNOPSIS...BELK/SIPPRELL NEAR TERM...KJC SHORT TERM...BELK LONG TERM...SIPPRELL AVIATION...KJC/SIPPRELL MARINE...BELK/KJC/SIPPRELL
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1255 PM EDT WED MAR 28 2012 .UPDATE... AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... A COLD FRONT SLOWLY SAGGING SOUTH THROUGH SOUTHERN CENTRAL INDIANA WILL KEEP LOW CHANCES FOR THUNDER AROUND THE SOUTHERN COUNTIES UNTIL MID AFTERNOON. MEANWHILE HIGH PRESSURE WILL BUILD IN FROM THE NORTH AND OVERSPREAD THE AREA BRINGING CLEARING SKIES. THE RIDGING WILL RESULT IN DRY WEATHER THROUGH FRIDAY WHEN THE NEXT DISTURBANCE ENTERS THE FORECAST AREA. BEYOND THAT...QUIET CONDITIONS FOR THE REMAINDER OF THE WEEKEND...AND THEN ANOTHER SYSTEM OVER THE GREAT LAKES REGION IS PROGGED FOR MONDAY. ITS ASSOCIATED COLD FRONT WILL TRIGGER THUNDERSTORM ACTIVITY ACROSS CENTRAL INDIANA. && .NEAR TERM /REST OF TODAY/... COLD FRONT HAS SLOWED IN ITS MOVEMENT THROUGH THE AREA AND CONTINUES TO SLOWLY SAG SOUTH. REMOVED POPS FROM AREAS NORTH OF THE FRONT...BUT EVEN THOUGH RPECIP HAS FOR THE MOST PART LEFT THE AREA RAPID UPDATE MODELS SUCH AS HRRR AND VSREFS SHOW REDEVELOPMENT OVER THE NEXT FEW HOURS ALONG/AHEAD OF THE FRONT SO WILL KEEP A LOW CHANCE POPS GOING ACROSS THE SOUTH INTO THE MID AFTERNOON. OTHERWISE HIGH PRESSURE CONTINUES TO BUILD IN FROM THE NORTH AND WILL CLEAR SKIES OUT FROM NORTH TO SOUTH THROUGH THE DAY. TEMPS...MODELS DO NOT SEEM TO BE ACCOUNTING FOR CLEARING VERY WELL...THUS SEEM A TAD LOW ON TODAY/S HIGHS. AS A RESULT...TRENDED A FEW DEGREES ABOVE GUIDANCE DUE TO SUFFICIENT SUNSHINE LATER TODAY. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... THE MAIN FOCUS OF THE SHORT TERM IS THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS ON FRIDAY. RIDGE WILL RE-ESTABLISH ITSELF ACROSS FORECAST AREA TONIGHT BRINGING DRY CONDITIONS THROUGH FRIDAY. HOWEVER...THE RIDGE WILL BREAK DOWN ON THURSDAY NIGHT AS A 500 MB SHORTWAVE APPROACHES CENTRAL INDIANA. THE GFS AND EURO ARE A TAD MORE PROGRESSIVE THAN THE NAM IN REGARD TO PRECIP ON THURSDAY NIGHT...BUT INCREASING ISENTROPIC LIFT SUPPORTS POPS AS EARLY AS FRI 06Z. THE BEST LIFT WILL OCCUR IN THE FRI 12-18Z TIME FRAME AS SHORT WAVE AND SURFACE LOW PASS OVER CENTRAL INDIANA. SO...INTRODUCED DEFINITE POPS INTO GRIDS DURING THAT PERIOD...WHICH MAY HAVE TO BE EXTENDED INTO FRIDAY NIGHT DEPENDING ON POSITION OF ASSOCIATED COLD FRONT. TEMPS...STUCK WITH A BLEND UNTIL FRIDAY. THAT/S WHEN MODELS STARTED HAVING A LITTLE TROUBLE WITH THE AFOREMENTIONED DISTURBANCE. TRENDED ON THE COOLER SIDE FOR DAYTIME HIGHS...AND LEANED ON THE WARMER SIDE FOR FRIDAY NIGHT LOWS DUE TO INCREASED CLOUD COVER. && .LONG TERM /SATURDAY THROUGH TUESDAY NIGHT/... THIS PERIOD BEGINS WITH SOME REMAINING LOW CHANCES FOR POPS AS FRONT IS PROGGED TO BE DROPPING SOUTH OF THE AREA BY SATURDAY AFTERNOON. MODELS HAVE BEEN INCREASINGLY PROGRESSIVE WITH THIS FRONT SO HAVE BACKED OFF ON POPS SLIGHTLY FOR SATURDAY. UPPER RIDGING BUILDS IN EARNEST BY SATURDAY NIGHT...AND PROVIDES QUIET DRY AND WARMER WEATHER FOR CENTRAL INDIANA THROUGH SUNDAY NIGHT. ANOTHER FRONT IS PROGGED TO APPROACH THE REGION SUNDAY NIGHT AND CROSS THE AREA MONDAY INTO MONDAY EVENING...BRINGING CHANCES FOR THUNDER BACK INTO THE FORECAST. RIDGE BUILDS BACK IN BY TUESDAY. && .AVIATION /DISCUSSION FOR 281800Z TAF ISSUANCE/... VFR THROUGH THE PERIOD AND EXCEPT FOR POSSIBLY KBMG...TAFS SHOULD BE MOSTLY CLEAR TOO. A WEAK COLD FRONT OVER SOUTHERN INDIANA MAY PRODUCE AN ISOLATED CB SOUTH OF KBMG EARLY THIS AFTERNOON. BUT I DON`T THINK IT WILL AFFECT ANY OF OUR TAF`S. THIS COLD FRONT WILL MOVE ON TO THE SOUTHEAST AS HIGH PRESSURE OVER THE NORTHERN PLAINS BUILDS EAST INTO THE GREAT LAKES LATER TONIGHT AND THURSDAY. MAIN ISSUE WILL BE WINDS THIS AFTERNOON AS SUSTAINED NORTHWEST WINDS UP TO 15 KNOTS AND GUSTS UP TO 25 KNOTS POSSIBLE. PRESSURE GRADIENT WILL DECREASE THIS AFTERNOON AND WINDS WILL BECOME LIGHT BY TONIGHT. ON THURSDAY WINDS WILL BECOME NORTHEAST 7 TO 10 KNOTS. SOME MID/HIGH CLOUDS MAY SPREAD SPREAD INTO SOUTHERN AND WEST SECTIONS BY MIDDAY THURSDAY AS A WARM FRONT STARTS TO APPROACH FROM THE SOUTHWEST. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD/CP NEAR TERM...TDUD/CP SHORT TERM...TDUD LONG TERM....SMF AVIATION...JH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
324 PM CDT WED MAR 28 2012 .DISCUSSION... ZONAL MID AND UPPER LEVEL FLOW WAS NOTED ACROSS THE CENTRAL AND SOUTHERN PLAINS. A MINOR H5 TROUGH WAS MOVING INTO NORTHWEST KS THIS AFTERNOON. AT 19Z...A WEAK SFC LOW WAS LOCATED NORTHEAST OF DDC. A WARM FRONT FRONT EXTEND EAST-NORTHEAST FROM THE SFC LOW ACROSS CENTRAL AND NORTHEAST KS. THE SFC WARM FRONT WAS LOCATED ABOUT 20 MILES NORTH OF I-70. SOUTH OF THE SFC WARM FRONT DEWPOINTS WERE IN THE LOWER 60S AND SBCAPE WAS IN THE 2,000 TO 2,500 J/KG RANGE. AS TEMPERATURES WARM LATER THIS AFTERNOON...SBCAPE WILL INCREASE TO 3,000 TO 3,500 J/KG ACROSS THE SOUTHERN HALF OF THE CWA. ELEVATED THUNDERSTORMS HAVE DEVELOPED NORTH OF THE WARM FRONT ACROSS SOUTH CENTRAL NE THIS AFTERNOON. THIS AREA OF STORMS WILL EXPAND EAST AND SOUTHEAST ACROSS NORTH CENTRAL KS LATE THIS AFTERNOON. ONCE THE STORMS REACH THE WARM SECTOR THE NEW UPDRAFTS WILL BECOME ROOTED IN THE BOUNDARY LAYER. 0-6KM BULK SHEAR WILL BE ABOUT 40 TO 50 KTS LATE THIS AFTERNOON AND THROUGH THE EVENING HOURS ACROSS THE CWA. GIVEN THE MODERATE VERTICAL WIND SHEAR AND INSTABILITY...THUNDERSTORM UPDRAFTS THAT DEVELOP ALONG AND SOUTH OF THE WARM FRONT WILL ROTATE. THE SUPERCELL THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL...MAY BE UP TO BASEBALL SIZE...AND DAMAGING OUTFLOW WINDS. THE LOW-LEVEL VERTICAL WIND SHEAR IS WEAKER...THUS TORNADO PROBABILITIES WILL BE LOW. HOWEVER...LATE THIS AFTERNOON AND EARLY THIS EVENING ACROSS NORTH CENTRAL KS BRIEF TORNADOES MAY BE POSSIBLE WITH ANY ISOLATED SUPERCELLS. ALSO, IF SUPERCELLS ARE ISOLATED ACROSS EAST CENTRAL KS THE RUC AND NAM MODELS SHOW THE BACKED LOW-LEVEL JET INCREASING TO 30 TO 40 KTS...WHICH WOULD PROVIDE A BETTER ENVIRONMENT FOR ANY ISOLATED SUPERCELL TO PRODUCE TORNADOES FROM 1Z TO 4Z. AS THE EVENING PROGRESSES THE ISOLATED TO SCATTERED SUPERCELL THUNDERSTORMS MAY CONGEAL INTO SEGMENTED SQUALL LINES OR QLCS`S. INDIVIDUAL UPDRAFTS MAY BE STRONG ENOUGH FOR LARGE HAIL...AND THE THREAT FOR DAMAGING WINDS MAY INCREASE WITH THE DEVELOPMENT OF A QLCS THROUGH THE EVENING HOURS ACROSS THE REMAINDER OF THE CWA. THE BEST CHANCES FOR THUNDERSTORMS THIS EVENING WILL BE ALONG AND NORTH OF THE WARM FRONT...WHICH WILL BE ABOUT I-70 NORTH TO THE NE BORDER. THOUGH STORMS WILL DEVELOP SOUTHEAST ACROSS THE REMAINDER OF THE CWA DURING THE LATE EVENING HOURS. THE THREAT FOR SEVERE WEATHER SHOULD DECREASE AFTER MIDNIGHT AS THE INSTABILITY DECREASES. IF A QLCS DEVELOPS THAN HEAVY RAINFALL MAY BE POSSIBLE LATER THIS EVENING ACROSS NORTHEAST AND EAST CENTRAL KS. THURSDAY...A MORE AMPLIFIED H5 TROUGH WILL MOVE ACROSS THE CENTRAL PLAINS DURING THE AFTERNOON HOURS. A SFC COLD FRONT WILL PUSH SOUTHEAST ACROSS NORTH CENTRAL KS BY AFTERNOON. SCATTERED THUNDERSTORMS WILL ONCE AGAIN DEVELOP ALONG AND AHEAD OF THE COLD FRONT. THE 12Z NAM MODEL FORECAST SBCAPE TO INCREASE TO AROUND 3,000 J/KG ACROSS THE WARM SECTOR. THUNDERSTORMS THAT DEVELOP MAY BECOME SEVERE. THE 0-6KM BULK SHEAR WILL BE A BIT STRONGER AHEAD OF THE H5 TROUGH BUT THE LOW-LEVEL WINDS AHEAD OF THE COLD FRONT WILL VEER THROUGH THE AFTERNOON. THEREFORE...THE PRIMARY HAZARD WITH ANY SUPERCELL THUNDERSTORM OR SQUALL LINE WILL BE LARGE HAIL AND DAMAGING OUTFLOW WINDS. SKIES WILL CLEAR BY MID MORNING INTO THE EARLY AFTERNOON HOURS. THUS THE INSOLATION AND SOUTHERLY WINDS AHEAD OF THE COLD FRONT WILL HELP HIGH TEMPERATURES TO REACH THE UPPER 70S TO LOWER 80S ACROSS THE CWA. IF THE SFC FRONT MOVES A BIT FASTER THEN NORTH CENTRAL KS MAY BE A FEW DEGREES COOLER. GARGAN CONVECTION TIED TO COLD FRONT EXPECTED TO MOVE OUT OF EASTERN KANSAS THURSDAY NIGHT...WITH CLEARING SKIES FOR FRIDAY. MUCH ABOVE NORMAL TEMPERATURES SHOULD CONTINUE THROUGH THE WEEKEND. NEXT CHANCE FOR PRECIPITATION WILL OCCUR WITH A STRONGER COLD FRONT COMING THROUGH SUNDAY NIGHT AS DEEP UPPER TROUGH MOVES ACROSS THE PLAINS. SOME WRAPAROUND SHOWERS LOOK LIKE THEY WILL LINGER INTO MONDAY ASSOCIATED WITH THE COLD AIR ALOFT BEHIND THE FRONT. TEMPERATURES TUESDAY MORNING COULD FALL INTO THE 30S BEHIND THAT SYSTEM...BUT WITH EXPECTED MIXING CONTINUING OVERNIGHT...WOULD NOT THINK THAT FROST WOULD BE LIKELY. DRY CONDITIONS AND A GRADUAL WARMUP IS THEN IN STORE FOR THE MIDDLE OF THE WEEK. 60 && .AVIATION... SATELLITE OBS SHOW A BAND OF VFR CLOUDS DRIFTING EASTWARD AROUND THE SURFACE LOW OVER NORTHWEST OKLAHOMA. A SURFACE WARM FRONT WILL SLOWLY LIFT NORTHWARD WITH DEVELOPING STRONG TO SEVERE TSRA OVER THE AREA AFTER 23Z AT KMHK AND 01Z AT KTOP/KFOE. KEPT VCTS AT THIS TIME AS EXACT TIMING OR COVERAGE OF THESE STORMS IS UNCERTAIN. WIND SPEEDS BELOW 10 KTS WILL VARY ALONG THE FRONTAL BOUNDARY FROM NORTHEAST AT KMHK TO EAST SOUTHEAST AT KTOP/KFOE THROUGH 20Z BEFORE BECOMING PREDOMINANTLY SOUTHEAST JUST ABOVE 10 KTS. MVFR CIGS ARE POSSIBLE AS THE PRECIPITATION CLEARS TAF SITES AFTER 05Z AT KMHK AND 07Z AT KTOP/KFOE. BOWEN && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
308 PM CDT WED MAR 28 2012 .DISCUSSION... THE PRIMARY FOCUS CONTINUES TO BE PERIODIC THUNDERSTORM CHANCES THROUGH THE WEEK. A BROAD MID/UPPER RIDGE WAS COVERING MUCH OF THE CENTRAL AND SOUTHERN CONUS WHILE A SUBTLE SHORTWAVE TROUGH WAS MOVING OVER SOUTHERN KANSAS EARLY THIS AFTERNOON. THE WARM FRONT HAS BECOME DIFFUSE MOST EVIDENT IN THE TD SPREADS LOCATED NEAR I-70 EARLY THIS AFTERNOON. STRONG CINH IS EXPECTED TO PRECLUDE MORE WIDESPREAD THUNDERSTORM DEVELOPMENT FURTHER SOUTH ALONG THE DRY LINE THIS AFTERNOON/EARLY EVENING BUT MAINTAINED HIGHER POPS ALONG AND NORTH OF THE DIFFUSE WARM FRONT BORDERING TOP CWA THIS EVENING/TONIGHT AS STRONGER 305K ISENTROPIC UPGLIDE BECOMES JUXTAPOSED ALONG THE NOSE OF THE LLJ. THE LATEST HRRR KEEPS THE MAIN AREA OF CONVECTION WELL NORTH OF THE FORECAST AREA...BUT MAINTAINED MID POPS ACROSS MUCH OF CENTRAL KANSAS WHERE THE ACTIVITY MAY DEVELOP BEFORE SHIFTING EASTWARD OUT OF THE AREA AFTER 09-11Z OR EARLIER. ANY STORMS THAT DEVELOP THROUGH TONIGHT MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS. THU-SUN...ABOVE NORMAL TEMPERATURES ARE ANTICIPATED THROUGH THE PERIOD WITH ANOTHER OPPORTUNITY FOR DEEP MOIST CONVECTION LATE THURSDAY AFTERNOON/THURSDAY NIGHT AS A SHORT WAVE TROUGH TRANSLATES RAPIDLY EAST OVER THE AREA. THE NAM IS MUCH MORE PROGRESSIVE WITH THE SFC TROUGH AXIS AND TRENDED POPS FURTHER EAST COMPARED TO THE PREVIOUS FORECAST KEEPING THE HIGHEST PROBABILITIES ALONG/EAST OF THE KANSAS TURNPIKE. SHORTWAVE RIDGING IS PROGGED TO RETURN TO THE CENTRAL PLAINS FRI-SAT LEADING TO FAIR WEATHER AND CONTINUED ABOVE NORMAL TEMPERATURES. TRENDED HIGHS ON FRI-SUN SLIGHTLY HIGHER WITH READINGS CLIMBING INTO THE LOW-MID 80S SAT-SUN. MON-WED...ANOTHER MORE ROBUST MID/UPPER TROUGH WILL RACE EASTWARD ACROSS THE CENTRAL PLAINS LATE SUNDAY INTO MONDAY BRINGING A RETURN TO SEASONABLE TEMPERATURES IN THE 60S INTO THE BEGINNING OF NEXT WEEK. PRECIPITATION CHANCES CONTINUE TO LOOK SLIM GIVIN THE PROGRESSIVE NATURE OF THE MID/UPPER TROUGH WITH A RETURN TO ABOVE NORMAL TEMPERATURES TOWARD THE MIDDLE OF THE WEEK. && .FIRE WEATHER... A TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS CENTRAL KANSAS ON THURSDAY WITH WIDELY SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE ALONG AND EAST OF THIS TROUGH. FURTHER WEST...LOW RELATIVE HUMIDITIES MAY COMBINE WITH GUSTY SOUTHWEST WINDS CREATING NEAR CRITICAL FIRE WEATHER CONDITIONS AT TIMES DURING THE AFTERNOON HOURS ON THURSDAY. GUSTY SOUTHWEST WINDS WILL RETURN LATE IN THE WEEKEND AHEAD OF A STRONG STORM SYSTEM MOVING OVER THE ROCKIES. GUSTY NORTHWEST WINDS WILL FOLLOW THE PASSAGE OF A COLD FRONT LATE SUNDAY NIGHT/EARLY MONDAY WITH A RETURN TO MORE SEASONABLE TEMPERATURES FOR THE BEGINNING OF NEXT WEEK. && .AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU AN AREA OF STRATUS/MVFR CIGS MIGRATED INTO CENTRAL KANSAS AT MIDDAY AND WILL GRADUALLY LIFT/DISSIPATE INTO MID-AFTERNOON. ISOLATED TO WIDELY SCATTERED CONVECTION IS EXPECTED TO DEVELOP BY EARLY THIS EVENING ALONG A WARM FRONT...FROM CENTRAL KANSAS INTO THE FLINT HILLS. THIS ACTIVITY SHOULD THEN MOVE OR DEVELOP EAST AND SOUTHEAST INTO FAR EASTERN KANSAS TONIGHT. SURFACE LOW PRESSURE WILL CONTINUE TO HANG OUT ACROSS CENTRAL KANSAS INTO THURSDAY MORNING...WITH A PERIOD OF LOW CIGS/MVFR EXPECTED ACROSS CENTRAL KANSAS. KED && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 61 85 56 79 / 30 30 20 10 HUTCHINSON 60 83 54 78 / 30 20 20 10 NEWTON 60 82 57 78 / 30 20 20 10 ELDORADO 61 84 59 79 / 30 30 30 10 WINFIELD-KWLD 62 85 58 81 / 20 20 40 10 RUSSELL 55 80 49 79 / 20 20 20 10 GREAT BEND 58 81 51 78 / 20 20 20 10 SALINA 59 83 54 80 / 30 20 20 10 MCPHERSON 61 82 54 79 / 30 20 20 10 COFFEYVILLE 63 85 59 81 / 30 20 60 20 CHANUTE 61 84 59 81 / 50 20 60 10 IOLA 61 83 59 81 / 50 20 60 10 PARSONS-KPPF 62 85 59 80 / 30 20 60 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
417 PM EDT WED MAR 28 2012 .SYNOPSIS... A WEAK COLD FRONT WILL CROSS THE REGION THIS EVENING. HIGH PRESSURE BUILDS OVER THE AREA THURSDAY AND FRIDAY. A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL AFFECT THE REGION LATE FRIDAY NIGHT THROUGH SATURDAY. HIGH PRESSURE RETURNS SUNDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... A WEAK COLD FRONT CONTINUES TO TRACK SOUTHWARD THIS AFTERNOON AND WILL PASS THROUGH OUR FA MAINLY BETWEEN 00Z AND 06Z THIS EVENING. AN INCREASED PRESSURE GRADIENT AHEAD OF THE FRONT IS RESULTING IN WARM BUT WINDY CONDITIONS THIS AFTERNOON. GUSTS BETWEEN 30-35 MPH WILL BE COMMON UNTIL SUNSET. CURRENT REGIONAL RADAR MOSAIC SHOWS A BROKEN LINE OF SHOWERS AND TSTMS ALONG THE FRONT. LATEST HRRR AND RUC FORECAST GUIDANCE HAS THE LINE MOSTLY DISSIPATING BEFORE REACHING OUR NORTHERN AREAS AROUND SUNSET. WILL MAINTAIN SLIGHT CHC POPS THROUGH THIS EVENING TO ACCOUNT FOR THE POSSIBILITY THAT THIS ACTIVITY HOLDS TOGETHER BUT NOT OVERLY CONFIDENT THAT IT WILL BE MUCH OF AN ISSUE GIVEN DRY LOW-LEVEL DOWNSLOPE FLOW AND LACK OF INSTABILITY. ONCE THE FRONT DROPS SOUTH OF THE FA OVERNIGHT WILL SEE WIND SHIFT TO THE NW. LOWS WILL BE MILDER THAN LAST NIGHT...IN THE 50S TO LOW 60S. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL BEGIN BUILDING SE ON THURSDAY. SHOULD BE ENOUGH OF A PRESSURE GRADIENT BETWEEN LOW PRESSURE OFF THE NEW ENGLAND COAST AND THE HIGH OVER THE GREAT LAKES TO ALLOW FOR BREEZY NW WINDS (ESPECIALLY EASTERN AREAS THROUGH MID AFTN). DRY AIRMASS BUILDING IN WITH THE SFC HIGH WILL ALLOW FOR PLENTY OF SUNSHINE. LOW-LEVEL THICKNESS VALUES/H85 TEMPS SUPPORT HIGHS FROM THE MID-60S ON THE LOWER MD EASTERN SHORE TO THE LOW/MID 70S IN THE SW ZONES. TURNING CHILLY AGAIN THURSDAY NIGHT WITH THE SFC HIGH BUILDING OVERHEAD AND DRY AIR IN PLACE. LOWS IN THE UPR 30S TO LOW 40S. FOR FRIDAY...THE SFC HIGH MOVES OFFSHORE AND ALLOWS FOR A S-SE FLOW. ANY PRECIP IS EXPECTED TO REMAIN TO OUR SOUTH ALONG A WEAK WARM FRONT. AN ONSHORE COMPONENT TO THE WIND WILL CAUSE THE COOLEST TEMPS TO BE NEAR THE COAST. HIGHS WILL RANGE FROM NR 60 ON THE LWR MD EASTERN SHORE TO THE LOW 70S IN OUR SW ZONES. AN AREA OF LOW PRESSURE WILL TRACK ACROSS THE REGION LATE FRIDAY NIGHT THROUGH SATURDAY MORNING BEFORE MOVING OFFSHORE SATURDAY AFTERNOON. BEST CHANCE FOR PRECIP WILL BE ACROSS OUR NORTHERN ZONES FRIDAY NIGHT...CLOSEST TO THE APPROACHING LOW. WILL THEN CARRY LOW END CHC POPS ALL AREAS ON SATURDAY AS THE SFC LOW TRAVERSES THE REGION. LOWS FRIDAY NIGHT IN THE UPR 40S TO MID 50S. HIGHS SATURDAY FROM THE 60S ON THE EASTERN SHORE TO THE MID/UPR 70S IN OUR SW ZONES. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... A COLD FRONT IS EXPECTED TO DROP THROUGH THE MID ATLANTIC SATURDAY NIGHT FOLLOWED BY HIGH PRESSURE BUILDING IN FROM THE NORTH LATE SATURDAY NIGHT INTO SUNDAY. THERE IS SOME DISAGREEMENT AMONGST MODEL GUIDANCE WITH RESPECT TO HOW QUICKLY THE HIGH MOVES OFF THE COAST SUNDAY AFTERNOON. GIVEN THAT THE HIGH APPEARS RATHER WEAK WILL GO WITH THE IDEA OF IT MOVING OFF THE COAST BY AFTERNOON WITH HIGH TEMPERATURES REACHING THE UPPER 60S IN THE EASTERN SHORE TO MID 70S IN THE PIEDMONT. LOW-LEVEL WARM AIR SURGES INTO THE REGION BY MONDAY ALONG WITH DOWNSLOPE FLOW AND THIS WILL RESULT IN MUCH WARMER HIGH TEMPERATURES. MAXIMA WERE RAISED INTO THE UPPER 70S TO LOW 80S WEST OF THE BAY...BUT LATEST LOW-LEVEL THICKNESSES WOULD SUPPORT LOW TO MID 80S INLAND. TUESDAY SHOULD REMAIN MILD AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. MOISTURE WITH THIS FRONT IS UNCERTAIN AT THIS TIME...SO SLIGHT CHANCE POPS WILL BE MAINTAINED. MORE SEASONAL TEMPERATURES SHOULD ARRIVE BEHIND THE FRONT FOR MIDWEEK. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... A STRONG SURFACE PRESSURE GRADIENT AHEAD OF A COLD FRONT APPROACHING FROM THE NORTH WILL CONTINUE TO DRIVE A 15-20KT SW WIND WITH 25-30KT GUSTS THROUGH LATE AFTERNOON/EARLY EVENING. A BROKEN LINE OF THUNDERSTORMS NEAR THE MASON-DIXON LINE AS OF 17-18Z IS EXPECTED TO DECREASE IN COVERAGE AND INTENSITY AS IT APPROACHES THE LOCAL THE LOCAL TAF SITES VERY LATE THIS AFTERNOON. SBY WOULD APPEAR TO HAVE THE BEST CHANCE (ALBEIT LOW) OF A TS AROUND 22-00Z...WITH A FEW SHOWERS PROGRESSING DOWN THE COAST LATER THIS EVENING. CONFIDENCE OF SHRA OR TS AFFECTING A TERMINAL IS LOW...SO NO WEATHER HAS BEEN INCLUDED WITH THE 18Z TAF ISSUANCE. THE COLD FRONT CLEARS THE REGION LATER TONIGHT WITH A GUSTY NW WIND DEVELOPING THURSDAY MORNING (ESPECIALLY NEAR THE COAST). THERE IS A POTENTIAL FOR ANOTHER ROUND OF 15-20KT SUSTAINED WIND WITH 25-30KT GUSTS. && .MARINE... A COLD FRONT CROSSES THE MID ATLANTIC COAST TONIGHT FOLLOWED BY HIGH PRESSURE BUILDING IN FROM THE NORTH THURSDAY. THE SW WIND OF TODAY WILL DECLINE THIS EVENING...BEFORE SHIFTING TO THE NW AND INCREASING ONCE AGAIN LATE. A MODESTLY STRONG NW WIND SHOULD CONTINUE DURING THE DAY THURSDAY...BEFORE DIMINISHING THURSDAY NIGHT AS HIGH PRESSURE SETTLES OVERHEAD. CURRENT SCA HEADLINES WILL BE MAINTAINED AS IS...ALTHOUGH LATEST GUIDANCE SUGGEST SCA CONDITIONS COULD END BEFORE THURSDAY NIGHT. HIGH PRESSURE SHIFTS OFFSHORE FRIDAY AS LOW PRESSURE APPROACHES FROM THE WEST. THIS AREA OF LOW PRESSURE CROSSES THE MARINE AREA FRIDAY NIGHT AND SATURDAY...WITH HIGH PRESSURE RETURNING SATURDAY NIGHT INTO SUNDAY. HIGH PRESSURE SETTLES OFF THE SOUTHEAST COAST EARLY NEXT WEEK. && .FIRE WEATHER... DRY AND BREEZY CONDITIONS ON THURSDAY MAY ENHANCE FIRE DANGER ESPECIALLY IF THERE IS NOT ANY RAIN WITH THE WEAK COLD FRONTAL PASSAGE TONIGHT. NW WINDS WILL AVERAGE 12-20 MPH THURSDAY WITH GUSTS UP TO 25 MPH. THE STRONGEST WINDS ARE EXPECTED DURING THE MORNING AND EARLY AFTERNOON. ALSO...RH VALUES ARE EXPECTED TO TUMBLE THURSDAY AFTERNOON...LIKELY FALLING INTO THE 22-32 PERCENT RANGE. AFTER COORDINATING WITH THE FIRE AGENCIES IN MD AND VA...WILL NOT BE ISSUING ANY HEADLINES ATTM BECAUSE CONFIDENCE IS NOT HIGH ENOUGH THAT WE SEE WIDESPREAD 20 MPH SUSTAINED WINDS...ESPECIALLY DURING PEAK HEATING IN THE AFTERNOON. WILL SEE HOW MUCH RAIN FALLS TONIGHT AND THEN WILL LIKELY ISSUE AN ENHANCED FIRE DANGER STATEMENT FOR A PORTION OF OUR MD AND VA COUNTIES EARLY THURSDAY MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT THURSDAY NIGHT FOR ANZ630>634-656-658. SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR ANZ650-652-654. && $$ SYNOPSIS...JDM NEAR TERM...JDM SHORT TERM...JDM LONG TERM...AJZ AVIATION...AJZ MARINE...AJZ FIRE WEATHER...JDM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
347 PM EDT WED MAR 28 2012 .SYNOPSIS... A WEAK COLD FRONT WILL CROSS THE REGION THIS EVENING. HIGH PRESSURE BUILDS OVER THE AREA THURSDAY AND FRIDAY. A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL AFFECT THE REGION LATE FRIDAY NIGHT THROUGH SATURDAY. HIGH PRESSURE RETURNS SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... A WEAK COLD FRONT CONTINUES TO TRACK SOUTHWARD THIS AFTERNOON AND WILL PASS THROUGH OUR FA MAINLY BETWEEN 00Z AND 06Z THIS EVENING. AN INCREASED PRESSURE GRADIENT AHEAD OF THE FRONT IS RESULTING IN WARM BUT WINDY CONDITIONS THIS AFTERNOON. GUSTS BETWEEN 30-35 MPH WILL BE COMMON UNTIL SUNSET. CURRENT REGIONAL RADAR MOSAIC SHOWS A BROKEN LINE OF SHOWERS AND TSTMS ALONG THE FRONT. LATEST HRRR AND RUC FORECAST GUIDANCE HAS THE LINE MOSTLY DISSIPATING BEFORE REACHING OUR NORTHERN AREAS AROUND SUNSET. WILL MAINTAIN SLIGT CHC POPS THROUGH THIS EVENING TO ACCOUNT FOR THE POSSIBILITY THAT THIS ACTIVITY HOLDS TOGETHER BUT NOT OVERLY CONFIDENT THAT IT WILL BE MUCH OF AN ISSUE GIVEN DRY LOW-LEVEL DOWNSLOPE FLOW AND LACK OF INSTABILITY. ONCE THE FRONT DROPS SOUTH OF THE FA OVERNIGHT WILL SEE WIND SHIFT TO THE NW. LOWS WILL BE MILDER THAN LAST NIGHT...IN THE 50S TO LOW 60S. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL BEGIN BUILDING SE ON THURSDAY. SHOULD BE ENOUGH OF A PRESSURE GRADIENT BETWEEN LOW PRESSURE OFF THE NEW ENGLAND COAST AND THE HIGH OVER THE GREAT LAKES TO ALLOW FOR BREEZY NW WINDS (ESPECIALLY EASTERN AREAS THROUGH MID AFTN). DRY AIRMASS BUILDING IN WITH THE SFC HIGH WILL ALLOW FOR PLENTY OF SUNSHINE. LOW-LEVEL THICKNESS VALUES/H85 TEMPS SUPPORT HIGHS FROM THE MID-60S ON THE LOWER MD EASTERN SHORE TO THE LOW/MID 70S IN THE SW ZONES. TURNING CHILLY AGAIN THURSDAY NIGHT WITH THE SFC HIGH BUILDING OVERHEAD AND DRY AIR IN PLACE. LOWS IN THE UPR 30S TO LOW 40S. FOR FRIDAY...THE SFC HIGH MOVES OFFSHORE AND ALLOWS FOR A S-SE FLOW. ANY PRECIP IS EXPECTED TO REMAIN TO OUR SOUTH ALONG A WEAK WARM FRONT. AN ONSHORE COMPONENT TO THE WIND WILL CAUSE THE COOLEST TEMPS TO BE NEAR THE COAST. HIGHS WILL RANGE FROM NR 60 ON THE LWR MD EASTERN SHORE TO THE LOW 70S IN OUR SW ZONES. AN AREA OF LOW PRESSURE WILL TRACK ACROSS THE REGION LATE FRIDAY NIGHT THROUGH SATURDAY MORNING BEFORE MOVING OFFSHORE SATURDAY AFTERNOON. BEST CHANCE FOR PRECIP WILL BE ACROSS OUR NORTHERN ZONES FRIDAY NIGHT...CLOSEST TO THE APPROACHING LOW. WILL THEN CARRY LOW END CHC POPS ALL AREAS ON SATURDAY AS THE SFC LOW TRAVERSES THE REGION. LOWS FRIDAY NIGHT IN THE UPR 40S TO MID 50S. HIGHS SATURDAY FROM THE 60S ON THE EASTERN SHORE TO THE MID/UPR 70S IN OUR SW ZONES. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... WILL LEAN A LITTLE CLSR TO THE 12Z ECMWF FOR THE EXTENDED PERIOD. A WRM FRNT WILL LIFT INTO THE AREA FRI NGT THRU SAT NGT...WITH LO PRES EXPECTED TO MOVE EWRD ALNG THE BNDRY...AND OFF THE CST. HAVE SML CHC FOR SHOWERS OR TSTMS DURING SAT...THEN SLGT OR SML CHC FOR SHOWERS SAT NGT INTO SUN MORNG. HI PRES WILL BLD IN AND PROVIDE DRY WX FOR SUN AFTN THRU MON. A COLD FRNT WILL THEN BRING AT LEAST A SLGT CHC FOR SHOWERS OR TSTMS MON NGT AND TUE. MIN TEMPS WILL MAINLY BE IN THE UPR 40S TO MID 50S THRU THE PERIOD. MAX TEMPS WILL RANGE FM THE MID 60S TO UPR 70S SAT...AND MAINLY RANGE FM THE MID 60S TO MID 70S SUN...MON AND TUE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... A STRONG SURFACE PRESSURE GRADIENT AHEAD OF A COLD FRONT APPROACHING FROM THE NORTH WILL CONTINUE TO DRIVE A 15-20KT SW WIND WITH 25-30KT GUSTS THROUGH LATE AFTERNOON/EARLY EVENING. A BROKEN LINE OF THUNDERSTORMS NEAR THE MASON-DIXON LINE AS OF 17-18Z IS EXPECTED TO DECREASE IN COVERAGE AND INTENSITY AS IT APPROACHES THE LOCAL THE LOCAL TAF SITES VERY LATE THIS AFTERNOON. SBY WOULD APPEAR TO HAVE THE BEST CHANCE (ALBEIT LOW) OF A TS AROUND 22-00Z...WITH A FEW SHOWERS PROGRESSING DOWN THE COAST LATER THIS EVENING. CONFIDENCE OF SHRA OR TS AFFECTING A TERMINAL IS LOW...SO NO WEATHER HAS BEEN INCLUDED WITH THE 18Z TAF ISSUANCE. THE COLD FRONT CLEARS THE REGION LATER TONIGHT WITH A GUSTY NW WIND DEVELOPING THURSDAY MORNING (ESPECIALLY NEAR THE COAST). THERE IS A POTENTIAL FOR ANOTHER ROUND OF 15-20KT SUSTAINED WIND WITH 25-30KT GUSTS. && .MARINE... A WINDY PERIOD ON TAP TODAY THROUGH THURSDAY EVENING. TIMING OF WHEN WNDS ACTUALLY REACH SCA LEVELS RATHER PROBLEMATIC. GIST OF FORECAST WAS TO INCREASE SW WINDS INTO SCA LEVELS OVER THE ENTIRE MARINE AREA. GIVEN WAA OVER COOLER WATERS...MIXING WILL BE LIMITED SO WILL STICK WITH A MINIMAL SCA ALTHOUGH THERE COULD BE SOME GUSTS ARND 25 KTS... ESPECIALLY NEAR THE SHORE. LATEST GUID SUGGESTS A LULL IN WINDS THIS EVENING FOR A FEW HOUR PERIOD EITHER SIDE OF THE FROPA...WITH CAA INCREASING THE WINDS LATER TONIGHT. DID NOT WANT TO SPLIT UP THE HEADLINES INTO 2 EVENTS SO WILL ONLY CARRY ONE LONG HEADLINE TO COVER BOTH SIDES OF THE FRONT TO KEEP IT SIMPLE. DECENT CAA THURSDAY WILL INCREASE LAPSE RATES AND ALLOW GOOD MIXING. BUFFER DATA SUGGESTS GUSTS ARND 30 KTS SO WILL CAP THE GUSTS AT THAT LEVEL ATTM. CONDITIONS SLOWLY IMPROVE BY FRIDAY AS HIGH PRESSURE BUILDS INTO THE AREA ALLOWING WINDS AND SEAS TO DROP BELOW SCA LEVELS. && .FIRE WEATHER... DRY AND BREEZY CONDITIONS ON THURSDAY MAY ENHANCE FIRE DANGER ESPECIALLY IF THERE IS NOT ANY RAIN WITH THE WEAK COLD FRONTAL PASSAGE TONIGHT. NW WINDS WILL AVERAGE 12-20 MPH THURSDAY WITH GUSTS UP TO 25 MPH. THE STRONGEST WINDS ARE EXPECTED DURING THE MORNING AND EARLY AFTERNOON. ALSO...RH VALUES ARE EXPECTED TO TUMBLE THURSDAY AFTERNOON...LIKELY FALLING INTO THE 22-32 PERCENT RANGE. AFTER COORDINATING WITH THE FIRE AGENCIES IN MD AND VA...WILL NOT BE ISSUING ANY HEADLINES ATTM BECAUSE CONFIDENCE IS NOT HIGH ENOUGH THAT WE SEE WIDESPREAD 20 MPH SUSTAINED WINDS...ESPECIALLY DURING PEAK HEATING IN THE AFTERNOON. WILL SEE HOW MUCH RAIN FALLS TONIGHT AND THEN WILL LIKELY ISSUE AN ENHANCED FIRE DANGER STATEMENT FOR A PORTION OF OUR MD AND VA COUNTIES EARLY THURSDAY MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT THURSDAY NIGHT FOR ANZ630>634-656-658. SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR ANZ650-652-654. && $$ SYNOPSIS...JDM NEAR TERM...JDM SHORT TERM...JDM LONG TERM... AVIATION...AJZ MARINE... FIRE WEATHER...JDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
404 PM EDT WED MAR 28 2012 .SYNOPSIS... ISSUED AT 355 PM EDT WED MAR 28 2012 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER THE UPR GRT LKS DOWNSTREAM OF UPR RIDGE IN THE PLAINS. SHRTWV/SFC LO THAT IMPACTED THE AREA YDAY IS NOW MOVING E THRU QUEBEC...BUT CYC SFC-H85 NW FLOW OF MOIST AIR REMAINS IN PLACE OVER THE UPR GRT LKS. A SHRTWV OVER MN IS MOVING SEWD...AND IN CONCERT WITH SOME DEEPER MSTR SHOWN ON THE 12Z INL RAOB HAS CAUSED SOME SCT -SHRA THAT ARE MIXING WITH SN AS COLDER AIR ARRIVES FM THE NW...WHERE THE 12Z H85 TEMP WAS AS LO AS -9C AT YPL. BUT UPSTREAM RAOBS SHOW MID LVL DRYING IN THE WAKE OF THE SHRTWV IS SPREADING SEWD TOWARD THE UPR GRT LKS. DESPITE THE HIER LVL DRYING...MUCH LO CLD LINGERS IN THE LLVL CYC FLOW OF THE MOISTER LLVLS DEPICTED ON THE 12Z INL/YPL RAOBS. SOME CLEARING IS SHOWING UP OVER MANITOBA CLOSER TO DRIER LLVL AIR SHOWN ON THE 12Z THE PAS RAOB AND SFC HI PRES/RDG AXIS UNDER THE UPR RDG. FARTHER TO THE W...A STRONG DISTURBANCE HAS COME ASHORE INTO THE PAC NW. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 355 PM EDT WED MAR 28 2012 MAIN FCST CONCERNS IN THIS PERIOD ARE CLD/CLEARING TRENDS AND TEMPS. TNGT...UPR RDG/SFC HI PRES RDG AXIS TO THE W ARE FCST TO BUILD INTO THE UPR GRT LKS. WITH MORE ACYC FLOW AND SOME DRYING...EXPECT AT LEAST PARTIAL CLRG ESPECIALLY IN DOWNSLOPE AREAS AWAY FM LK SUP IN SLOWLY VEERING FLOW TO MORE NNE BY 12Z THU. BUT EXTENSIVE CLD COVER UPSTREAM/LINGERING H925 THERMAL TROF SUGS THE SC WL BE MORE RESILIENT IN UPSLOPE AREAS NEAR THE LAKE UNDER STRENGTHENING INVRN ASSOCIATED WITH LARGER SCALE SUBSIDENCE. EXPECT THE LOWEST MIN TEMPS WELL DOWN IN THE 20S OVER THE INTERIOR W WHERE MORE EXTENSIVE CLRG IS MOST LIKELY. THU...AS HI PRES IN ONTARIO DRIFTS SLOWLY TO THE E AND DISTURBANCE NOW IN THE PAC NW/SFC LO MOVE TOWARD MN LATE...THE LLVL FLOW WL VEER TO THE E THRU THE DAY. LINGERING LK SC SHOULD SHIFT TO MAINLY OVER THE HURON MTNS/KEWEENAW AS MID/HIER CLD IN ADVANCE OF APRCHG DISTURBANCE ARRIVE IN THE AFTN. THE GFS IS MOST AGGRESSIVE AT MOVING PCPN E INTO THE WRN CWA IN THE AFTN...BUT WL FOLLOW THE SLOWER 12Z NAM/CNDN/UKMET AND 00Z ECWMF WITH VERY DRY AIRMASS ASSOCIATED WITH HUDSON BAY HI PRES IN PLACE AND GFS FCST SHARPER QVECTOR CNVGC/FGEN HOLDING FARTHER TO THE W. MIXING TO H85 ON NAM FCST SDNGS YIELDS HI TEMPS APRCHG 45 AWAY FM LK MODERATION. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 355 PM EDT WED MAR 28 2012 THURSDAY NIGHT INTO FRIDAY...SHORTWAVE TROUGH OVER THE NORTHERN PLAINS POISED TO SLIDE THROUGH THE WESTERN GREAT LAKES BY LATE THURSDAY NIGHT. INITIALLY JUST TO THE WEST OF CWA LARGE SCALE LIFT FM THE SHORTWAVE IS COMPLEMENTED NICELY BY 925-850MB WARM AIR ADVECTION AND DIVERGENCE ALOFT FM JET STREAK OVR ONTARIO. ALL THIS FORCING IS ACTING ON RATHER MOIST AIRMASS WITH PWATS UP TOWARD 200 PCT OF NORMAL. SINCE PRIMARY SHORTWAVE IS SLIDING MAINLY SOUTH OF UPR MI AND RIGHT ENTRANCE REGION/H85 THERMAL GRADIENT FADES THROUGH THE NIGHT...WOULD EXPECT PCPN TO LIGHTEN AS IT MOVES INTO THE CWA OVERNIGHT. FCST SOUNDINGS POINT TO PTYPE MAINLY TAKING THE FORM OF SNOW WITH VERY LITTLE IN WAY OF NEAR SFC WARM LAYER ON SOUNDINGS. BASED ON PREVIOUS MODEL RUNS THIS REPRESENTS A TREND IN THE COOLER DIRECTION. EXPLICIT QPF OUTPUT WITH THE COLDER TREND WOULD SUGGEST A FEW INCHES OF SNOW POSSIBLE IN THE INTERIOR WEST OVERNIGHT THURSDAY NIGHT INTO EARLY FRIDAY. WILL NOT GO WITH THAT MUCH QPF/SNOW YET THOUGH BASED ON NEGATIVE FACTORS MENTIONED BEFORE. STILL...COULD SEE AROUND AN INCH OF SNOW OVER INTERIOR WEST AND SCNTRL. MAJORITY OF PCPN SHOULD EXIT THE SCNTRL/EASTERN CWA FRIDAY AFTN. PLENTY OF CLOUDS WITH THE PCPN ALONG WITH SE WIND OFF LK MICHIGAN WILL HOLD DOWN TEMPERATURES OVR MOST OF THE CWA IN THE LOWER-MID 40S. SHORTWAVE TROUGH SLIDES BY OVER CNTRL CANADA ON SATURDAY BUT MAIN IMPACTS FM DISTURBANCE FCST TO REMAIN MOSTLY NORTH OF CWA WHERE BEST LOW-LEVEL WARM ADVECTION OCCURS AND ALONG AND EAST OF TRACK OF SHORTWAVE. DO HAVE SOME SMALL CHANCES FOR SHOWERS /JUST RAIN AT THIS POINT/ OVER LK SUPERIOR AND IN NORTHERN CWA ON SATURDAY NIGHT. IN THE EXTENDED...PIECE OF BROAD UPPER TROUGH OVER THE NORTHERN PACIFIC IS FORECAST TO EJECT ACROSS THE ROCKIES ON SUNDAY. TROUGH AND ASSOCIATED DEEPENING SFC LOW THEN SLIDE INTO THE UPR LAKES ON MONDAY. DETERMINISTIC MEDIUM RANGE MODELS /GFS/ECMWF/CANADIAN/ INDICATE THAT THE UPPER LOW SLOWS UP EARLY NEXT WEEK AND MAY EVEN TRY TO CUT OFF OVR UPR LAKES AND/OR ONTARIO. NCEP PREFERS THE SLOWER APPROACH AS MODELS HAVE TRENDED THAT WAY. EVENTUALLY GENERAL RESULT WILL BE COOLER AND UNSETTLED WEATHER PATTERN THROUGH MIDDLE OF NEXT WEEK. INITIALLY THOUGH...MONDAY COULD BE ON THE WARMER SIDE OUT AHEAD OF UPR LOW. ECMWF AND GFS DIFFER ON DETAILS AS GFS SHOWS MUCH MORE IN WAY OF CLOUDS AND LIGHTER QPF SUNDAY NIGHT INTO MONDAY MORNING WHILE ECMWF INDICATES A SHARPER COLD FRONT WITH GREATER POTENTIAL FOR CONVECTION JUST AHEAD OF THE FRONT WITH H7-H5 LAPSE RATES TO 7C/KM AND SI/S BLO 0C. THERE ALSO APPEARS TO BE ENHANCED CONVECTIVE POTENTIAL DUE TO SHARPER 1000-850MB MOISTURE FLUX CONVERGENCE FCST IN AFTN DURING PEAK HEATING. LATEST GFS HAS TRENDED WARMER WITH INCREASED CHANCE OF CONVECTION. HAVE INTRODUCED CHANCES FOR THUNDER...FIRST ON SUNDAY NIGHT FOR POSSIBLE ELEVATED CONVECTION ON EDGE OF INSTABILITY GRADIENT AND THEN ON MONDAY WITH THE FROPA. COLDER AIR WORKS IN FOR TUESDAY AND WEDNESDAY. GFS IS BROADER AND LESS AMPLIFIED WITH OVERALL TROUGH WHILE ECMWF INDICATES COOLER AIR SLOWLY MOVING IN ON TUESDAY WITH STRONGER SHOT OF COLD AIR ARRIVING BY WEDNESDAY WITH SHARPER COLD FRONT FCST. ALTHOUGH CONSISTENCY IN HANDLING OF THE TROUGH FM THE MODELS HAS BEEN MUDDLED...DOES APPEAR TO BE A TREND IN HOLDING ON TO THE TROUGH LONGER AND KEEPING COOLER TEMPERATURES OVER GREAT LAKES LONGER FURTHER INTO THE WEEK. TREND MAKES SOME SENSE GIVEN THE AMPLIFIED PATTERN THAT APPEARS TO BE SETTING UP COMPARED TO MORE ZONAL PATTERN IN PLACE CURRENTLY. LATEST ECMWF SLOWER YET IN KEEPING COOL TROUGHING OVER GREAT LAKES AND NORTHEAST INTO LATE NEXT WEEK. TRYING TO PIN DOWN DETAILS TOUGH AT THIS POINT...BUT THIS KIND OF PATTERN WOULD HAVE POTENTIAL TO BRING RAIN/SNOW SHOWERS TO UPR LAKES...ENHANCED BY DAYTIME HEATING AND/OR ANY SHORTWAVES MOVING AROUND THE TROUGH. CONSENSUS POPS SHOW SMALL CHANCES THROUGH MUCH OF THE EXTENDED WHICH SEEMS ON TRACK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 133 PM EDT WED MAR 28 2012 EXPECT GUSTY WINDS TO DIMINISH THIS PERIOD AND VEER TO ENE AT ALL SITES AS HI PRES RDG/WEAKER PRES GRADIENT BUILDS INTO THE UPR GRT LKS. ALTHOUGH MORE ACYC FLOW/SOME LLVL DRYING WL RESULT IN CONDITIONS IMPROVING TO VFR BY THIS EVNG...EXTENSIVE LO CLD/CIGS OBSERVED UPSTREAM SUGGEST A MORE PESSIMISTIC CIG FORECAST THAN SHOWN ON PREVIOUS TAFS. OPTED TO FCST AN MVFR CIG LATER TNGT/EARLY THU AT CMX/SAW DURING TIMES OF UPSLOPE FLOW. THE BEST CHC OF A MORE PERSISTENT VFR CONDITION WL BE AT IWD...WHERE EXPECTED ENE LLVL FLOW WL DOWNSLOPE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 355 PM EDT WED MAR 28 2012 EXPECT NW WINDS UP TO 30 KTS EARLY OVER THE E HALF TO DIMINISH TONIGHT AS HI PRES RIDGE BUILDS OVERHEAD. AS THE HI CENTER SHIFTS EWD TOWARD HUDSON BAY ON THU...A STRONGER E WIND UP TO 25 KTS WILL DEVELOP OVER WESTERN LK SUP WHERE TERRAIN ENHANCES THIS FLOW. GUSTY EAST WINDS SHOULD CONTINUE ON THE LAKE INTO FRIDAY MORNING. AFTER A BRIEF LULL...SOUTH WINDS INCREASE TO 30 KTS ON EAST HALF OF LK SUPERIOR BY SATURDAY AFTN. WINDS SHOULD SETTLE DOWN INTO SUNDAY AS PRESSURE GRADIENT WEAKENS. ANOTHER LOW PRESSURE SYSTEM...POSSIBLY SLOW MOVING...IS EXPECTED TO AFFECT THE WESTERN GREAT LAKES EARLY NEXT WEEK. COULD SEE WINDS UP TO 30 KTS WITH THIS SYSTEM. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...KC SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
321 PM CDT WED MAR 28 2012 .SHORT TERM... ISSUED AT 320 PM CDT WED MAR 28 2012 (TONIGHT THROUGH FRIDAY) PRIMARY CONCERN IN THE SHORT TERM IS POPS TONIGHT THROUGH FRIDAY. QUASI-STATIONARY FRONT EXTENDS FROM NEAR FARMINGTON WEST-NORTHWEST BETWEEN COLUMBIA AND SEDALIA TO NEAR TOPEKA. UNSTABLE AIRMASS IS EVIDENT IN CUMULUS FIELD SOUTH OF THE FRONT AND SHOWERS ARE ALREADY BREAKING OUT SOUTH OF THE ST LOUIS METRO AREA. EXPECT WIDELY SCATTERED SHOWERS TO CONTINUE ALONG AND SOUTH OF THE FRONT THIS AFTERNOON AND INTO THIS EVENING...BUT THE MAIN SHOW WILL DEVELOP ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS WHERE INSTABILITY AND FORCING IS GREATEST. SOME QUESTION AS TO WHAT CONVECTIVE MODE THE STORMS WILL ULTIMATELY TAKE. INSTABILITY AND SHEAR IS GREAT ENOUGH FOR SOME ORGANIZATION...AND THE HRRR HAS ALTERNATELY BEEN DEVELOPING DISCRETE SUPERCELLS...BOW ECHOS...AND OCCASIONALLY MULTICELL CLUSTERS. THINK EITHER THE MULTICELL CLUSTER OR BOW ECHO IS MOST LIKELY. FORWARD PROPAGATING CORFIDI VECTORS WOULD MOVE ANY MCS THAT DEVELOPS EAST-SOUTHEAST INTO WESTERN MISSOURI. STORMS SHOULD RUN OUT OF INSTABILITY AS THEY APPROACH CENTRAL MISSOURI AND SHOULD BE IN THE WANING PHASE. WILL CONTINUE THE CHANCE FOR WIDELY SCATTERED THUNDERSTORMS ON THURSDAY AS FRONT LIFTS BACK ACROSS THE AREA...THEN ANOTHER SHOT OF PRECIP THURSDAY NIGHT AS A SHORTWAVE RIPPLES ACROSS IOWA AND MISSOURI ACCOMPANIED BY ANOTHER WEAK COLD FRONT. CARNEY && .LONG TERM... ISSUED AT 320 PM CDT WED MAR 28 2012 (SATURDAY THROUGH WEDNESDAY) PRIMARY CONCERN IN THE SHORT TERM IS POPS TONIGHT THROUGH FRIDAY. QUASI-STATIONARY FRONT EXTENDS FROM NEAR FARMINGTON WEST-NORTHWEST BETWEEN COLUMBIA AND SEDALIA TO NEAR TOPEKA. UNSTABLE AIRMASS IS EVIDENT IN CUMULUS FIELD SOUTH OF THE FRONT AND SHOWERS ARE ALREADY BREAKING OUT SOUTH OF THE ST LOUIS METRO AREA. EXPECT WIDELY SCATTERED SHOWERS TO CONTINUE ALONG AND SOUTH OF THE FRONT THIS AFTERNOON AND INTO THIS EVENING...BUT THE MAIN SHOW WILL DEVELOP ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS WHERE INSTABILITY AND FORCING IS GREATEST. SOME QUESTION AS TO WHAT CONVECTIVE MODE THE STORMS WILL ULTIMATELY TAKE. INSTABILITY AND SHEAR IS GREAT ENOUGH FOR SOME ORGANIZATION...AND THE HRRR HAS ALTERNATELY BEEN DEVELOPING DISCRETE SUPERCELLS...BOW ECHOS...AND OCCASIONALLY MULTICELL CLUSTERS. THINK EITHER THE MULTICELL CLUSTER OR BOW ECHO IS MOST LIKELY. FORWARD PROPAGATING CORFIDI VECTORS WOULD MOVE ANY MCS THAT DEVELOPS EAST-SOUTHEAST INTO WESTERN MISSOURI. STORMS SHOULD RUN OUT OF INSTABILITY AS THEY APPROACH CENTRAL MISSOURI AND SHOULD BE IN THE WANING PHASE. WILL CONTINUE THE CHANCE FOR WIDELY SCATTERED THUNDERSTORMS ON THURSDAY AS FRONT LIFTS BACK ACROSS THE AREA...THEN ANOTHER SHOT OF PRECIP THURSDAY NIGHT AS A SHORTWAVE RIPPLES ACROSS IOWA AND MISSOURI ACCOMPANIED BY ANOTHER WEAK COLD FRONT. THE FRONT WILL CONTINUE SOUTH INTO THE LOWER MISSISSIPPI VALLEY BY SATURDAY BRINGING AN END TO THE PRECIP CHANCES FOR THE WEEKEND. TEMPERATURES SHOULD REMAIN ABOVE NORMAL IN THE UPPER 70S TO THE LOWER 80S. A SHARP TROF WILL DEVELOP OVER THE PLAINS SUNDAY NIGHT INTO MONDAY WITH SURFACE CYCLOGENESIS TAKING PLACE OVER THE NORTHEAST PLAINS OR THE UPPER MIDWEST. SOME TIMING DIFFERENCES ON MEDIUM RANGE MODELS IS MAKING PRECIP TIMING DIFFICULT...BUT EXPECT SHOWERS AND THUNDERSTORMS TO BE IN THE AREA MONDAY AND MONDAY NIGHT...POSSIBLY LINGERING INTO TUESDAY. EXPECTING TEMPERATURES BEHIND THE FRONT TO BE MORE SEASONABLE IN THE 60S AND LOWER 70S. CARNEY && .AVIATION... ISSUED AT 1226 PM CDT WED MAR 28 2012 FRONT BISECTS THE CWA WITH ALL TERMINALS TO THE NORTH OF THIS FEATURE WITH CLEAR SKIES AND LIGHT NORTHERLY WINDS. FRONT IS ATTEMPTING TO BUCKLE BACK NORTH ACROSS WESTERN MISSOURI AND THIS IS WHERE CONVECTIVE INITIATION WILL TAKE PLACE THIS EVENING. AT THIS TIME IT APPEARS THAT AN MCS WILL DEVELOP NEAR KANSAS CITY AND MOVE EAST/SOUTHEAST INTO CENTRAL MISSOURI AND THE OZARKS OVERNIGHT. HAVE MAINTAINED A PERIOD OF SHOWERS AT KCOU...WITH JUST AN INCREASE OF HIGH/MID LEVEL CLOUDS ELSEWHERE. SPECIFICS FOR KSTL... VFR CONDITIONS EXPECTED AS FRONT HAS DRIFTED SOUTH OF THE TERMINAL. LIGHT NORTH WIND WILL CONTINUE WITH ONLY AN INCREASE IN HIGH/MID LEVEL CLOUDS FROM CONVECTION THAT WILL REMAIN WEST OF THE TERMINAL THROUGH AT LEAST 12Z. CVKING && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
303 PM MDT WED MAR 28 2012 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY... AN OPEN SHORTWAVE TROUGH AND COLD FRONT MOVES OVER WESTERN AND CENTRAL MONTANA TODAY. THUNDERSTORMS ARE EXPECTED WITH THE FRONT. THIS EVENING THE FRONT SPREADS ACROSS NORTHEAST MONTANA...LOSING SOME OF ITS PUNCH. A FEW THUNDERSTORMS MIGHT MAKE IT INTO OUR WESTERN ZONES...BUT CAPE THAT IS APPARENT TO OUR WEST DISSIPATES BY 00Z. BOTH THE RUC AND GFS BRING SCATTERED RAIN SHOWERS WITH THIS FRONT THIS EVENING...MAINLY OVER PHILLIPS AND VALLEY COUNTIES. KEPT ISOLATED POPS IN ACROSS THE AREA AFTER MIDNIGHT. A LEE SURFACE TROUGH SHIFTING EAST ACROSS THE AREA THE MOSTLY SOUTHEASTERLY WINDS WILL SHIFT TO THE NORTHWEST. AFTER PASSAGE OF THE TROUGH...FLOW ALOFT BECOMES MOSTLY ZONAL WHILE SURFACE WINDS BECOME SOUTHWESTERLY THROUGH FRIDAY...WHICH WILL TREND TEMPERATURES UPWARD. THICKNESS HEIGHTS BEGIN THURSDAY MORNING AROUND 540DM...THEN INCREASE TO OVER 550DM BY EVENING. SO EXPECT MAXIMUM TEMPERATURES TO WARM TO AROUND 15F DEGREES ABOVE NORMAL. WEAK UPPER RIDGING WILL WILL BRING MOSTLY SUNNY SKIES FOR A MILD DAY. THICKNESS HEIGHTS INCREASE TO AROUND 560DM ON FRIDAY SO HIGHS COULD REACH AROUND 25F DEGREES ABOVE NORMAL. HOWEVER A SIGNIFICANT AMOUNT OF PACIFIC MOISTURE MOVES INTO THE NORTHERN ROCKIES AND DISTURBANCES IN THE FLOW ALOFT WILL INCREASE CLOUD COVER...WHICH COULD INITIATE A FEW SHOWERS IN THE AFTERNOON. WHILE MET AND MAV GUIDANCE SUGGEST WARM TEMPERATURES...OVERCAST SKY COVER COULD LIMIT MAXIMUM TEMPERATURES LOWER THAN GUIDANCE. SCT .LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY... THE BULK OF CHANGES WERE MADE IN REGARDS TO THE LATE WEEKEND SYSTEM. MODELS CONTINUE TO STRUGGLE WITH THE DETAILS OF THE LOW PRESSURE SYSTEM FOR SATURDAY NIGHT INTO SUNDAY NIGHT. BUT GIVEN ANY SOLUTION A PATTERN CHANGE IS IN STORE FOR NORTHEAST MONTANA...WITH COOLER MORE NORMAL TEMPERATURES LINGERING INTO EARLY NEXT WEEK. THUS CONSERVATIVELY TRENDED UP POPS FOR THE SATURDAY NIGHT INTO SUNDAY NIGHT TIME-FRAME. ALSO TRENDED UP WINDS AS SUNDAY INTO MONDAY LOOKS WINDY AS THE SURFACE LOW MOVES THROUGH. OTHERWISE ANY OTHER TWEAKS WERE MINOR AS UPPER RIDGING BUILDS IN NEXT WEEK. GILCHRIST PREVIOUS LONG TERM DISCUSSION...A MODERATELY STRONG LOW PRESSURE SYSTEM FROM THE W ARRIVES THIS WEEKEND...WHICH MODELS AGREE WITH AND ALL PRODUCE SIGNIFICANT PRECIP OVER PARTS OF NE MT. DIFFERENCES THOUGH ON LOCATION IN NE MT...AS MOST...BUT NOT ALL...RECENT MODELS KEEP THE STRONGER PART OF THE SYSTEM OVER CANADA. ALSO WITH POOR MODEL HANDLING OF PAST FEW SYSTEMS AND THE DRY PATTERN OF LATE...WILL GO SOMEWHAT CONSERVATIVE WITH POPS. 2 PERIODS OF CHANCE POPS LOOK PLENTY ADEQUATE. THE AIR-MASS WITH THIS SYSTEM WILL BE UNSTABLE ENOUGH FOR SHOWERY PRECIP...AND POSSIBLY AN ISOLATED THUNDERSTORM...ALTHOUGH MODELS TEND OVERLY UNSTABLE IN EARLY SPRING. STRONG COLD ADVECTION FOLLOWS...BUT THEY VARY QUITE A BIT TOO ON WHETHER THERE WILL BE ENOUGH COLD ADVECTION FOR SOME PRECIP TO END AS SNOW LATE SAT NIGHT. ADDED SNOW SHOWER MENTION TO ONLY N VALLEY AND SW PHILLIPS ZONES. A VERY WINDY DAY SUNDAY THOUGH AS 850 WINDS OF 35 TO 50 KT LIKELY TO MIX TO THE SURFACE. FOR THE REST OF THE FORECAST PERIOD...POOR MODEL AGREEMENT. MOST MODELS FAVOR RIDGING WITH DRY WEATHER AND MODEST WARMING. LATEST GFS WAS AN OUTLIER WITH OTHER MODELS THOUGH AND LOOKS THAT WAY ON ITS ENSEMBLES AS IT BREAKS THE RIDGE DOWN VERY QUICK TUE/WED. SIMONSEN && .AVIATION... VFR CONDITIONS WILL LARGELY DOMINATE AT ALL THE TERMINALS OVER THE NEXT 24 HOURS. A WEAK FRONTAL PASSAGE THIS EVENING WILL BRING A FEW SHOWERS...BUT CEILINGS AND OR VISIBILITY IS EXPECTED TO REMAIN VFR. GUSTY SOUTHEAST WINDS WILL CONTINUE THROUGH EARLY EVENING...WHEN THEY WILL DECREASE TO AROUND 10KTS. A WIND SHIFT WILL OCCUR WITH THE SURFACE FRONT AFTER MIDNIGHT FROM SOUTHEAST TO NORTHWEST. NORTHWEST WINDS WILL CONTINUE INTO THURSDAY MORNING...AND SKIES WILL GRADUALLY CLEAR BY MIDDAY THURSDAY. GILCHRIST && .FIRE WEATHER... WILL CONTINUE TO WATCH THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON. METEOROLOGICAL CONDITIONS REMAIN MARGINAL FOR CRITICAL FIRE WEATHER CONDITIONS...BASED ON RELATIVE HUMIDITIES IN THE LOWER 20S AND WINDS OF 15-20 MPH. FIRE WEATHER CONDITIONS COULD BECOME CRITICAL ON FRIDAY AFTERNOON...ALSO BASED ON EXPECTED WARM TEMPERATURES...RESULTING IN LOW RELATIVE HUMIDITIES...ALONG WITH SOUTHWEST WINDS OF AROUND 20MPH. SCT && .CLIMATE... THE FIRST 27 DAYS OF MARCH ARE THE WARMEST ON RECORD IN GLASGOW. THE AVERAGE TEMPERATURE OF 40.7 DEGREES IS 10.0 DEGREES ABOVE NORMAL. WE HAVE A GOOD CHANCE OF SETTING THE ALL-TIME RECORD FOR THE ENTIRE MONTH OF MARCH...WHICH WAS MARCH 1986. MARCH WILL MAKE FOR THE 9TH STRAIGHT MONTH THAT HAS BEEN WARMER THAN NORMAL. THE 26 DAY PERIOD FROM THE 2ND TO THE 27TH...ONLY 0.07 INCH OF PRECIP FELL...WHICH IS TIED FOR 10TH DRIEST. DUE TO 0.33 ON THE FIRST...MARCH AS A WHOLE WILL NOT RANK AS UNUSUALLY DRY. SIMONSEN && .GLASGOW WATCHES/WARNINGS/ADVISORIES... LAKE WIND ADVISORY UNTIL 6 PM MDT THIS EVENING FOR FORT PECK LAKE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
100 PM EDT WED MAR 28 2012 .SYNOPSIS... A COLD FRONT WILL PASS SOUTHEAST THROUGH THE REGION TODAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...LEADING TO TRANQUIL CONDITIONS ON THURSDAY. ON FRIDAY...A LOW PRESSURE SYSTEM WILL DEVELOP IN THE CENTRAL PLAINS AND MOVE INTO THE REGION...BRINGING THE NEXT CHANCE OF PRECIPITATION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... GOING FORECAST IN GOOD SHAPE AND ONLY MINOR TWEAKS NEEDED THIS MORNING. 28.12Z KILN RAOB INDICATED IN EXCESS OF 1000 J/KG OF ELEVATED INSTABILITY FOR PARCELS LIFTED FROM ABOUT 900MB...AND NO DOUBT SOME OF THIS BEING REALIZED WITH SHOWERS/SCT STORMS SEEN ON KILN WSR-88D THIS MORNING. FORCING FOR ASCENT THUS FAR DRIVEN BY LOW LEVEL THETA-E ADVECTION JUST ABOVE THE INVERSION...AS SFC COLD FRONT ATTENDANT TO THE GREAT LAKES SHORTWAVE TROUGH IS STILL BACK IN NWRN OH INTO SWRN IND. FRONT SHOULD PASS QUICKLY SOUTHEAST THROUGH THE ILN FORECAST AREA THROUGH 6 PM...AND THERE IS REMARKABLE AGREEMENT FROM THE CONVECTION ALLOWING MODELS /NSSL-WRF...NCEP ARW WRF...AND HRRR/ THAT CONVECTION WILL SLOWLY DEVELOP THROUGH THE DAY ALONG/JUST AHEAD OF THE FRONT...PEAKING IN THE FAR SOUTHERN/SERN FORECAST AREA BETWEEN 2PM AND 5 PM. BEST CHANCE FOR A STRONGER STORM IN THE LOWER SCIOTO VALLEY AND NERN KY...WHERE BEST INSTABILITY /MLCAPE AROUND 1000 J/KG/ WILL HAVE BUILT. 28.12Z RUC FORECAST SOUNDINGS AT PMH VALID 20Z INDICATE DEEP WLY TROPOSPHERIC FLOW...AND STRONG...SUGGESTING SOME STORM ORGANIZATION IS LIKELY BUT NOT DIRECTIONAL SHEAR IS DEFINITELY LACKING. WIND/HAIL THE MAIN THREATS IN THE FAR SOUTH. BACK TO THE N/W BEHIND THE FRONT IN WCNTL/CNTL OH...AMPLE SUNSHINE AND CRASHING DEWPOINTS/COLD ADVECTION WILL BRING WINDS UP IN THE MID TO LATE AFTERNOON WHICH SHOULD GET SOME GUSTS ABOVE 30KTS IN THE WIND PRONE AREAS. LAPSE RATES ON FCST SOUNDINGS ARE STEEP WITH A STRONG FLOW IN THE BOUNDARY LAYER. CHANGES THIS MORNING TO FORECAST TO BUMP WINDS UP JUST A BIT IN THE NORTH...AND BUMP RAIN CHANCES IN THE SOUTH UP A BIT. OTHERWISE FCST IN GOOD SHAPE. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... HIGH PRESSURE WILL FILL IN BEHIND THE COLD FRONT FOR TONIGHT AND THURSDAY...AS NORTHWEST FLOW CONTINUES ALOFT. THE COOL DOWN BEHIND THE FRONT WILL RESULT IN A 10-15 DEGREE DROP FROM WEDNESDAY TO THURSDAY...WITH WARM ADVECTION NOT REALLY KICKING BACK IN UNTIL THURSDAY NIGHT. THIS WILL LEAD TO TWO NIGHTS ON THE COOL SIDE OF THINGS. TEMPERATURES IN THE FAR NORTH ON WEDNESDAY NIGHT APPEAR THAT THEY MAY BE COLD ENOUGH TO SUPPORT SOME FROST...ALTHOUGH A LACK OF MOISTURE MAY PRECLUDE THIS FROM OCCURRING. CONDITIONS FOR A FREEZE IN CENTRAL OHIO ON THURSDAY NIGHT LOOK SLIGHTLY LESS FAVORABLE THAN THEY DID PREVIOUSLY (WITH A BUMP FORWARD IN TIMING ON THE NEXT WEATHER SYSTEM)...BUT THERE IS CERTAINLY STILL ENOUGH OF A CHANCE TO KEEP AN HWO MENTION. MODEL GUIDANCE REMAINS IN POOR AGREEMENT FOR THE SYSTEM ON FRIDAY AND SATURDAY. OF CONCERN IS THE FACT THAT THE ECMWF HAS BEEN STEADY IN ITS SLOWER SOLUTION WITH A DEEPER MID-LEVEL TROUGH...WHILE THE GFS AND NAM ARE BOTH IN REMARKABLE AGREEMENT ON A FASTER PROGRESSION AND STRONGER SURFACE LOW. THUS...CONFIDENCE IN THE FORECAST FROM FRIDAY AND BEYOND IS BELOW AVERAGE. PRECIPITATION OVER THE FORECAST AREA IS CERTAIN TO OCCUR DURING THIS TIME FRAME...AND THE OVERALL TREND HAS BEEN SLIGHTLY SPED UP IN THIS FORECAST PACKAGE. ASIDE FROM THE PRECIPITATION CHANCES...THE TRACK AND STRENGTH OF THE SURFACE LOW WILL ALSO HAVE MAJOR IMPLICATIONS ON FRONTS...TEMPERATURES...AND ANY POTENTIAL SEVERE THREAT. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... TEMPERATURES WILL BE ABOVE NORMAL WITH HIGHS IN THE 60S AND 70S. THE COOLEST DAY LOOKS TO BE SATURDAY WITH LOW TO MID 60S FORECAST DUE TO COLD ADVECTION AND CLOUDS BEHIND THE LOW. THE WARMEST READINGS INTO THE MID 70S ARE FORECAST FOR MONDAY WHEN ADVECTION OCCURS AHEAD OF THE COLD FRONT. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... 18Z TAFS WILL FEATURE VFR CONDITIONS FOR ALL THE SITES...AS IT IS EXPECTED THAT THUNDERSTORM ACTIVITY WILL BE SOUTH/EAST OF KCVG/KLUK BY 18Z. THEREFORE...TAFS MAINLY DEAL WITH GUSTY AFTERNOON WINDS TODAY AS COLD FRONT SHIFTS THROUGH AND COLD ADVECTION AND STEEPENING LAPSE RATES YIELD SOME WNWLY GUSTS TO 25 OR 30KTS. DO EXPECT SOME SCT CUMULUS TO FORM THIS AFTERNOON ESPECIALLY NEAR CNTL OH BUT SHOULD BE VFR. WATCHING ANOTHER BATCH OF STRATOCUMULUS OVER WI/LOWER MI THAT MAY TRY TO STRETCH INTO CNTL OH AND THE MIAMI VALLEY LATER TONIGHT. RIGHT NOW THINKING IT WILL BREAK UP/SCATTER AS IT DOES SO. WILL HINT AT THIS LOW CONFIDENCE ITEM WITH SCTO25-SCT030 HOWEVER. FLOW SHOULD TURN NLY OVERNIGHT AND NOT COMPLETELY DECOUPLE...WINDS STAYING ABOVE 5KTS IN MOST AREAS. COULD EVEN TURN NELY FOR A TIME AT THE CINCINNATI AREA TERMINALS. A QUIET THURSDAY IN STORE WITH RESIDUAL STRATOCUMULUS /AT THIS TIME EXPECTED TO BE VFR AND SCATTERED/ WITH LIGHT NLY FLOW. OUTLOOK...THUNDERSTORMS POSSIBLE FRIDAY INTO SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...BINAU SHORT TERM...HATZOS LONG TERM...CONIGLIO AVIATION...BINAU
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
345 PM CDT WED MAR 28 2012 .SHORT TERM... CONVOLUTED PATTERN IN PLACE ACROSS THE AREA GIVEN THE LARGE CONVECTIVELY ENHANCED DISTURBANCE LOCATED TO OUR SE AND GENERAL WEAK KINEMATICS ACROSS WEST TEXAS. THE DRYLINE HAS REMAINED FAIRLY DIFFUSE THROUGH THE DAY ALTHOUGH AS OF 3 PM...SOME BACKING OF THE SFC WINDS HAVE BEEN NOTED ALONG WITH SOME CUMULUS DEVELOPMENT FROM ERN GAINES COUNTY THROUGH BRISCOE COUNTY. MEANWHILE...AN OUTFLOW BOUNDARY FROM THE MCS IS MOVING TOWARD THE SRN ROLLING PLAINS WITH NEAR 60F DEWPOINTS APPROACHING STONEWALL COUNTY. THERE IS LITTLE INDICATION OF A CONVECTIVE SIGNAL IN ANY OF THE OBJECTIVE GUIDANCE FOR THE REMAINDER OF THE AFTERNOON AND EVENING...ALTHOUGH RUC ANALYSIS SHOWS THE ATMOSPHERE TO BE NEARLY UNCAPPED WITH ABOUT 500-1000 J/KG OF CAPE IN MUCH OF THE ROLLING PLAINS. ALOFT...THERE IS ANOTHER WEAK WAVE LOCATED IN NRN MX BUT THIS IS LIKELY TOO FAR REMOVED TO PROVIDE SIGNIFICANT LIFT THIS EVENING. THUS THE ENVIRONMENT IS JUST MARGINALLY SUPPORTIVE OF CONVECTIVE DEVELOPMENT...WITH WEAK DRYLINE FORCING WE CAN/T RULE OUT A FEW ISOLD STORMS MAINLY ACROSS THE SRN SPLNS AND ROLLING PLAINS. THE MAIN STORM THREAT WILL BE STRONG DOWNDRAFT WINDS BUT IF A STORM CAN TAP INTO THE DEEPER MOISTURE MOVING IN FROM THE SE THERE MAY BE A MARGINAL HAIL THREAT AS WELL. THE DRYLINE SHOULD RETREAT THROUGH MOST OF THE FA OVERNIGHT...WITH HOPEFULLY NO REPEAT OF THE NOCTURNAL MCS INTERCEPTING OUR MOISTURE RETURN. SOME LIGHT FOG IS AGAIN EXPECTED EARLY THU MORNING...FOLLOWED BY THE DRYLINE MIXING INTO THE WESTERN ROLLING PLAINS BY EARLY AFTERNOON. FCST SDNGS SHOW THAT THE AIRMASS SHOULD WARM UP NICELY IN THE DRY AIR WITH AFTERNOON HIGHS APPROACHING 90F ACROSS THE SRN AND CENTRAL SPLNS. GIVEN THE DEGREE OF SFC HEATING...A LITTLE MORE SHARPLY DEFINED DRYLINE...AND INCREASED LARGE-SCALE ASCENT AS A SHORTWAVE APPROACHES FROM THE WEST LATE IN THE DAY...WE THINK THE POTENTIAL WILL IMPROVE FOR CONVECTIVE INITIATION ALONG THE DRYLINE THU AFTERNOON/EVE. FCST SDNGS SHOW A DEEP DRY-ADIABATIC CONVECTIVE BOUNDARY LAYER ALONG THE DRYLINE BY LATE AFTERNOON WITH NO INHIBITION...AND MODEST MLCAPES...AROUND 1000 J/KG OR SO. IN ADDITION...SFC TO 6 KM SHEAR WILL BE FAIRLY WEAK. THIS WILL LIMIT STORM ORGANIZATION...AND KEEP STRONG WIND GUSTS AND MARGINALLY LARGE HAIL AS THE MAIN THREATS. SOME UNCERTAINTY WITH TIMING OF THE LIFT AND DRYLINE LOCATION PREVENT US FROM GOING HIGHER THAN SLIGHT CHANCE FOR NOW. && .LONG TERM... LARGELY UNEVENTFUL FORECAST FOR MUCH /IF NOT ALL/ OF THE EXTENDED FORECAST AS MECHANISMS FOR ASCENT APPEAR HARD TO COME BY WITHIN WEAK WESTERLY UPPER FLOW. EVEN THE RECENT DRYLINE IS PROGGED TO REMAIN DIFFUSE DURING THE AFTERNOON TOMORROW AND FRIDAY AS IT MIXES ALONG OR JUST EAST OF THE EDGE OF THE CAPROCK. VERTICAL CIRCULATIONS WITH SUCH DRYLINES ARE GREATLY REDUCED...BUT WE HAVE RETAINED SOME MENTION OF PRECIP OFF THE CAP THU NIGHT AS A SHALLOW S/W TROF IN THE CENTRAL PLAINS GLANCES THE REGION. ALSO...SUBTLE UPPER DIVERGENCE ASSOCIATED WITH AN APPROACHING UPPER WIND MAX COULD OFFER A BIT MORE ASSISTANCE FOR ISOLATED THUNDER BEFORE LIFT DIMINISHES LATE IN THE NIGHT. DESPITE A FRONTOLYSIZING COLD FRONT DRIFTING SOUTH FROM THE PANHANDLE ON FRIDAY BEHIND THE S/W TROF...SUBTLE RIDGING ALOFT THROUGHOUT THE PLAINS IS NOT BODING WELL FOR STORM CHANCES FRIDAY AFTERNOON. NAM CONTINUES TO CONVECT THIS DAY...ALTHOUGH THIS RECENT OVERZEALOUS NATURE OF THE MODEL HAS NOT ENJOYED MUCH SUCCESS SO WE ARE QUITE DOUBTFUL OF ITS QPF. APPROACH OF A PROGRESSIVE PACIFIC TROUGH BY THE WEEKEND WILL SECURE STRONGER W-SWLY WINDS IN THE LOW-MID TROPOSPHERE. SUBSEQUENT BOOST OF THICKNESSES SHOULD EASILY PUSH MOST AREA HIGHS AOA 90 DEG AS THE DRYLINE MIXES NEAR OR JUST BEYOND OUR ERN COUNTIES. TREND WITH THIS NEXT TROUGH HAS BEEN TO SLOW DOWN A BIT AMONG THE GFS/ECMWF/GEFS MEAN AND THIS WOULD DELAY THE ARRIVAL OF STRONGEST WINDS INTO THE PANHANDLE AND NWRN SOUTH PLAINS. BIGGEST CHANGE HERE CONCERNS THE IMPENDING PACIFIC FRONT THAT IS NOW PROGGED TO RID MUCH OF THE LONE STAR STATE OF GULF MOISTURE ON MONDAY AS THE BASE OF THE TROF BECOMES -TILTED AND DIVES INTO THE OZARKS. THIS WILL LIKELY DELAY THE RETURN OF MOISTURE MUCH LATER THAN EARLIER FORECASTS SUGGESTED...SO A DRY START TO APRIL APPEARS IN ORDER. TEMPS SHOULD PLUMMET BLO NORMAL FOR A CHANGE ON MONDAY WITH GRADUAL MODIFICATION THEREAFTER. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 46 85 44 82 48 / 10 10 10 10 10 TULIA 50 87 48 85 49 / 10 20 10 10 10 PLAINVIEW 50 88 49 86 50 / 10 20 10 10 10 LEVELLAND 49 89 50 87 50 / 10 10 10 10 10 LUBBOCK 54 90 53 88 52 / 10 20 10 10 10 DENVER CITY 49 89 50 86 50 / 10 10 10 10 10 BROWNFIELD 50 90 52 86 51 / 10 20 10 10 10 CHILDRESS 58 89 56 88 54 / 10 20 20 10 10 SPUR 55 88 56 87 53 / 20 20 20 10 10 ASPERMONT 61 87 58 87 56 / 10 20 20 10 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 33/93
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1233 PM CDT WED MAR 28 2012 .DISCUSSION... SEE 18Z AVIATION DISCUSSION BELOW. && .AVIATION... CURRENTLY...THERE IS AN AREA OF SHOWERS AND THUNDERSTORMS MOVING NORTH/NORTHWEST TOWARD THE KBBD TERMINAL. THIS IS LIKELY A RESULT OF A SMALL MID LEVEL DISTURBANCE SPINNING OVER THE WESTERN HILL COUNTRY AREA. EXPECT THIS ACTIVITY TO IMPACT BRADY BETWEEN NOW AND 19Z BEFORE GENERALLY DISSIPATING. ALSO EXPECT MOST OF THE ACTIVITY ASSOCIATED WITH THIS DISTURBANCE TO BEGIN MOVING EASTWARD AS THE DISTURBANCE DOES AS WELL. OVERNIGHT...WE MAY SEE ISOLATED TO SCATTERED THUNDERSTORMS DEVELOP WEST OF THE AREA...AND TRY TO MOVE EAST TOWARD OUR TAF SITES...BUT EXPECT THE ACTIVITY TO DISSIPATE DURING THE EVENING HOURS BEFORE GETTING A CHANCE TO MAKE SIGNIFICANT PROGRESS INTO OUR FORECAST AREA. OVERNIGHT...SOUTHEAST WINDS SHOULD CONTINUE. MODEL SOUNDINGS SUGGEST THAT LOW CLOUDS WILL STRUGGLE TO IMPACT KSJT AND KABI...SO HAVE ONLY INCLUDED A SCT020 GROUP FOR THESE SITES DURING THE EARLY MORNING HOURS WHILE MVFR CIGS ARE EXPECTED TO IMPACT KSOA...KJCT AND KBBD. 20 && .PREV DISCUSSION... /ISSUED 1042 AM CDT WED MAR 28 2012/ DISCUSSION... HAVE MADE SOME MINOR ADJUSTMENTS TO CLOUD COVER AND MAX TEMPS FOR TODAY AS WELL AS WX/POP GRIDS TO ACCOUNT FOR DEVELOPING SHOWERS/STORMS ACROSS OUR SOUTHEASTERN COUNTIES. THE HRRR SHOWS THIS ACTIVITY DISSIPATING DURING THE AFTERNOON...SO WILL KEEP THE AREA CONFINED TO OUR SOUTHEASTERN COUNTIES FOR NOW...AND KEEP AN EYE ON IT. HAVE SLIGHTLY LOWERED MAX TEMPS FOR SOUTHERN AREAS WHERE MORE CLOUD COVER AND THE AFOREMENTIONED PRECIPITATION IS OCCURRING. UPDATED GRIDS HAVE BEEN PUBLISHED. 20 PREV DISCUSSION... /ISSUED 555 AM CDT WED MAR 28 2012/ DISCUSSION... /SEE BELOW FOR AVIATION DISCUSSION/ AVIATION... STRATUS WITH MVFR CIGS WAS REDEVELOPING ACROSS WEST CENTRAL THIS MORNING...HAVING BEEN PARTIALLY DISRUPTED BY MCS OVER SOUTH CENTRAL TEXAS. CIGS EXPECTED TO LIFT OR SCATTER OUT BY LATE MORNING ACROSS WEST CENTRAL TEXAS. WHILE AN ISOLATED THUNDERSTORM POSSIBLE LATE AFTERNOON AND EVENING...BEST CHANCE OF STORMS WILL NEAR SONORA...MAINLY AFTER 3Z. HAVE STRATUS WITH MVFR CIGS RETURNING AT CLIMATOLOGICAL FAVORABLE TIMES TONIGHT...6Z AT KJCT AND KSOA...7Z AT KBBD...AND 9Z AT SJT. PREV DISCUSSION... /ISSUED 348 AM CDT WED MAR 28 2012/ SHORT TERM... MCS THAT MOVED THROUGH CROCKETT AND SUTTON COUNTIES OVERNIGHT...WAS MOVING THROUGH THE HILL COUNTRY AND RIO GRANDE RIVER THIS MORNING...AS FAR SOUTH AS LAREDO. MCS DEVELOPED IN THE HIGHER ELEVATIONS AROUND FT STOCKTON YESTERDAY AFTERNOON...THEN MOVED SOUTHEAST. IT HAS LEFT AN OUTFLOW BOUNDARY IN THE CONCHO VALLEY. WITH DAYTIME HEATING...POTENTIAL EXISTS FOR SOME ISOLATED THUNDERSTORMS TO DEVELOP ALONG THE REMNANT THUNDERSTORM OUTFLOW BOUNDARY LATE AFTERNOON. THERE IS A BETTER CHANCE OF STORMS TONIGHT HOWEVER...TO THE WEST AND SOUTH OF THE CONCHO VALLEY...AS BOTH NAM AND GFS MODELS INDICATED ANOTHER AREA OF CONVECTION TO REDEVELOP IN HIGHER ELEVATIONS AROUND FORT STOCKTON...THEN MOVE SOUTHEAST. APPROACH OF AN UPPER TROUGH NEAR BAJA CALIFORNIA WILL HELP PROVIDE ADDITIONAL LIFT. DEVELOPMENT AND PATH OF MCS REMAINS PROBLEMATIC HOWEVER... AS STEERING CURRENTS ALOFT ARE WEAK...AND MCS MOVEMENT WILL BE DEPENDENT IF OR WHERE A STRONG COLD POOL DEVELOPS. WILL KEEP HIGHEST POPS OVER CROCKETT COUNTY TONIGHT. LONG TERM... UPPER LEVEL SHORTWAVE EVIDENT ON WATER VAPOR NEAR BAJA WILL SLIDE INTO WEST CENTRAL TEXAS FOR THURSDAY...AIDING CONVECTIVE DEVELOPMENT. RIGHT NOW...WILL FOCUS POPS ON THURSDAY ACROSS THE SOUTHERN COUNTIES...WHERE A REMNANT MCS FROM TONIGHT AND/OR ITS BOUNDARIES MAY STILL BE IN THE AREA...AND ALONG THE WESTERN CONCHO VALLEY AND BIG COUNTRY ALONG THE DRYLINE. WILL THEN SPREAD THE RAIN CHANCES AREAWIDE FOR THURSDAY NIGHT. STILL SOME QUESTION ABOUT THE SPEED OF THE SHORTWAVE AND HOW QUICKLY IT WILL EXIT TO THE EAST...BUT FOR RIGHT NOW...WILL CONTINUE THE TREND IN THE CURRENT FORECAST AND WILL CARRY SLIGHT SOME POPS FOR THE EASTERN AREA INTO FRIDAY AS WELL. UPPER LEVEL SUPPORT FOR ANY CONVECTIVE DEVELOPMENT OVER THE WEEKEND WILL BE QUESTIONABLE...AND BEST INSTABILITY WILL BE ALONG THE EASTERN BORDER OF THE AREA. COULD RUN ISOLATED POPS FOR THE FEW STORMS THAT MAY DEVELOP...BUT AT THIS POINT...WILL JUST OPT TO NOT INCLUDE A MENTION AT ALL. FAIRLY STRONG FRONTAL BOUNDARY MOVES THROUGH THE AREA ON MONDAY...KNOCKING DOWN THE WELL ABOVE TEMPERATURES DOWN TO SOMETHING CLOSER TO NORMAL. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 61 84 61 85 57 / 10 20 30 20 10 SAN ANGELO 60 83 60 84 56 / 20 30 30 20 10 JUNCTION 61 80 62 80 57 / 20 30 40 20 20 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
347 PM CDT WED MAR 28 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT 347 PM CDT WED MAR 28 2012 AT 3 PM...A 1020 MB SURFACE HIGH WAS CENTERED OVER THE EASTERN DAKOTAS AND WESTERN MINNESOTA. THIS HIGH WILL DRIFT EAST ACROSS THE AREA TONIGHT. MEANWHILE A TROUGH OF LOW PRESSURE...LOCATED OVER NORTHEAST WISCONSIN...WAS PRODUCING A BROKEN DECK OF CLOUDS ACROSS NORTHERN MINNESOTA...AND NORTHERN AND EASTERN WISCONSIN. THE VISIBLE SATELLITE LOOP SHOWS THAT THESE CLOUDS ARE CELLULAR IN NATURE...THEREFORE...EXPECT THAT THESE CLOUDS WILL CONTINUE TO QUICKLY ERODE AND DISSIPATE LATE THIS AFTERNOON AND EVENING. WITH CLEAR SKIES AND LIGHT WINDS EXPECTED TONIGHT...TEMPERATURES ALONG AND NORTH OF THE INTERSTATE 94 CORRIDOR WILL LIKELY FALL INTO THE UPPER 20S. DUE TO THIS...A FREEZE WARNING HAS BEEN ISSUED FOR THESE AREAS. DUE TO THE URBAN HEAT ISLAND AND THE PROXIMITY TO THE UNUSUALLY WARM MISSISSIPPI RIVER...THE CITY OF LA CROSSE MAY NOT SEE FROST...BUT THE REMAINDER OF LA CROSSE COUNTY WILL LIKELY SEE FROST ALONG WITH BUFFALO...TREMPEALEAU...AND VERNON COUNTIES. DUE TO THIS...A FROST ADVISORY HAS BEEN ISSUED FOR THESE COUNTIES FOR TONIGHT. ON THURSDAY...THE CLOUDS WILL BE ON THE INCREASE AS A SHORT WAVE TROUGH MOVES TOWARD THE REGION FROM THE DAKOTAS. THIS SYSTEM WILL THEN MOVE EAST THROUGH THE REGION ON THURSDAY NIGHT AND EARLY FRIDAY MORNING. THIS IS A BIT FASTER THAN PREVIOUS MODEL RUNS... SO THE PRECIPITATION WAS REMOVED FOR FRIDAY AFTERNOON. ALONG WITH SHOWERS...THE MOST UNSTABLE CAPES CLIMB UP TO 250 J/KG. DUE TO THIS...KEPT ISOLATED THUNDERSTORMS IN THE FORECAST FROM LATE THURSDAY AFTERNOON INTO THURSDAY NIGHT. ON FRIDAY AND FRIDAY NIGHT...ANOTHER AREA OF COOLER AIR WILL SPILL INTO THE WESTERN GREAT LAKES BEHIND THE DEPARTING SHORT WAVE TROUGH. BOTH OF THESE TIME PERIODS HAVE BEEN GETTING PROGRESSIVELY COOLER ACROSS WISCONSIN. DUE TO THIS...LOWERED THE TEMPERATURES A FEW MORE DEGREES THAN THE PREVIOUS FORECAST. UNLIKE TONIGHT... THERE LOOKS LIKE THERE MAY BE A BIT MORE CLOUDS. HOWEVER IF THERE IS LESS CLOUDS...WE MAY HAVE ANOTHER NIGHT FOR POTENTIAL FROST AND FREEZE HEADLINES ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN. .LONG TERM...SATURDAY THROUGH WEDNESDAY 347 PM CDT WED MAR 28 2012 ON SATURDAY...THE MODELS CONTINUE TO SHOW THAT THE COLDER AIR WILL BE MUCH SLOWER AT MOVING OUT OF THE WESTERN GREAT LAKES. AS A RESULT...LOWERED THE MAXIMUM TEMPERATURES A FEW MORE DEGREES. THESE TEMPERATURES ARE NOT QUITE AS COLD WHAT THE ECMWF OR GEM IS INDICATING...SO THEY MAY HAVE TO BE LOWERED EVEN MORE. ON SUNDAY...850 MB TEMPERATURES WILL CLIMB INTO 16 TO 18C RANGE AND SOUTHERLY WINDS IN THE 10 TO 20 KNOT RANGE. THIS WILL ALLOW TEMPERATURES TO CLIMB WELL INTO MID AND UPPER 70S. THERE MAY BE EVEN A FEW LOW 80S. ON SUNDAY NIGHT...IT LOOKS LIKE THE COLD FRONT WILL BE A BIT SLOWER MOVING INTO THE REGION. AS A RESULT...THE PRECIPITATION CHANCES WERE REMOVED FROM THE FORECAST. && .AVIATION...THROUGH 18Z THURSDAY 1236 PM CDT WED MAR 28 2012 MAIN AVIATION FORECAST CONCERNS IS LOW PRESSURE OVER THE GREAT LAKES REGION WRAPPING STRATOCUMULUS CLOUD DECK INTO THE REGION THIS AFTERNOON AND INTO THE EARLY EVENING HOURS. CEILING HEIGHTS WITHIN THE STRATOCUMULUS DECK ARE IN THE MVFR RANGE OF 2000 TO 3500 FEET. THE COMBINATION OF ABUNDANT SUNSHINE AHEAD OF THE DECK OF CLOUDS AND SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE NORTHERN PLAINS...STRATOCUMULUS DECK IS SLOWLY ERODING ON SOUTHERN FLANK PER LATEST VISIBLE SATELLITE IMAGERY. LATEST 28.15Z RUC AND 28.12Z NAM SHOW STRATOCUMULUS DECK TO HOLD TOGETHER BEFORE ERODING LATE THIS AFTERNOON AND EARLY EVENING HOURS PER RELATIVE HUMIDITY FIELDS AT 850MB AND 925MB. FOR NOW...HAVE INTRODUCED BROKEN LAYER AT MVFR CONDITIONS AT KRST AND ADDED A TEMPO GROUP OF SCATTERED CLOUDS THROUGH 22Z WEDNESDAY. AT KLSE...CEILINGS HEIGHTS SHOULD BE ABOVE 3000 FEET AND IN THE VFR RANGE. NEXT AVIATION CONCERN IS APPROACHING COLD FRONT FOR THURSDAY. LATEST DETERMINISTIC 28.12Z MODELS SHOW PRESSURE GRADIENT TIGHTENING AND WIND DIRECTION SHIFTING TO SOUTHEAST AFTER 13Z THURSDAY. SUSTAIN WIND SPEEDS ARE EXPECTED TO BE AROUND 15 KNOTS AND GUST UP TO AROUND 20 KNOTS...ESPECIALLY AT KRST. && .ARX WATCHES/WARNINGS/ADVISORIES... 253 PM CDT WED MAR 28 2012 WI...FROST ADVISORY FROM 1 AM TO 9 AM CDT THURSDAY FOR WIZ032-033-041- 053. FREEZE WARNING FROM 1 AM TO 9 AM CDT THURSDAY FOR WIZ017-029-034- 042>044. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...DTJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1237 PM CDT WED MAR 28 2012 .SHORT TERM... 356 AM CDT WED MAR 28 2012 FORECAST CONCERNS THIS PACKAGE...FROST POTENTIAL TONIGHT...RAIN CHANCES CENTERED ON THU NIGHT...TEMPERATURES. DATA ANALYSIS AT 06Z HAD A BROAD AREA OF LOW PRESSURE CENTERED JUST NORTH OF LK SUPERIOR. PRESSURE GRADIENT AROUND THIS LOW STILL EXTENDED ACROSS MN/WI/MUCH OF IA AND CONTINUED TO RELAX EARLY THIS MORNING. WINDS ACROSS MOST OF MN/WI REMAINED IN THE 10-20KT RANGE. CLOUDS IN THE CIRCULATION AROUND THE LOW COVERED CENTRAL/ NORTHERN MN AND WI NORTH OF HWY 29...WITH GENERALLY CLEAR SKIES ELSEWHERE ACROSS THE UPPER MIDWEST. TEMPS ACROSS THE REGION COOLING IN THE WEST/NORTHWEST FLOW BUT REMAINED WELL ABOVE NORMAL. 28.00Z MODELS INITIALIZED WELL. SOLUTIONS QUITE SIMILAR FOR TODAY THRU THU THEN DIVERGE WITH THE STRENGTH/TIMING OF THE SHORTWAVE AND SFC LOW/TROUGH TO MOVE ACROSS THE MID/UPPER MS VALLEY THU NIGHT. DPROG/DT OF 500MB HGTS AT 28.00Z SHOWED THE RUNS OF 26.00Z AND 27.00Z VERIFIED WELL ACROSS NOAM/EASTERN PAC WITH BETTER RUN-TO-RUN CONSISTENCY BY ECMWF. MODELS CONVERGING TOWARD A TIGHTER CONSENSUS THRU THU AS THE NEXT SHORTWAVE ENERGY FROM THE PACIFIC MOVES INTO THE CENTRAL/NORTHERN PLAINS BY 00Z FRI. FROM THERE MODELS DIVERGE WITH THE EVOLUTION OF THIS TROUGH AS IT MOVES EAST THRU THE REGION THU NIGHT/FRI. SOMEWHAT BETTER RUN-TO-RUN CONSISTENCY BY ECMWF THU NIGHT THRU FRI NIGHT...BUT COULD BE BETTER. CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED MODELS ON TRACK WITH THE SFC FEATURES OVER CENTRAL NOAM. PER WV IMAGERY...ECMWF/GEM LOOKED BETTER THAN NAM/GFS/MET WITH THE SHORTWAVE ENERGY IN THE TROUGH APPROACHING THE WEST COAST. ECMWF/GEM ARE A COUPLE OF THE SLOWER SOLUTIONS WITH THIS ENERGY AS IT CROSSES THE MID/UPPER MS VALLEY THU NIGHT/FRI. WITH ECMWF/GEM LOOKING BETTER AT 06Z...FAVORED A MODEL/ENSEMBLE CONSENSUS WEIGHTED TOWARD THEM ESPECIALLY THU NIGHT/FRI. HOWEVER GIVEN THE MODEL SPREAD FCST CONFIDENCE FALLS TO AVERAGE FOR THU NIGHT THRU FRI NIGHT. FOR THE SHORT TERM...THE LOW NORTH OF LK SUPERIOR MOVES QUICKLY AWAY FROM THE REGION TODAY. HOWEVER MDT 925 PRESSURE GRADIENT/WINDS REMAIN OVER THE AREA MUCH OF THE DAY. WITH PLENTY OF SUNSHINE AND MODEL SOUNDINGS INDICATING MIXING TO AROUND 900MB...WINDS WILL REMAIN BRISK/BREEZY TODAY. SFC RIDGE AXIS DRIFTS RATHER QUICKLY EAST ACROSS THE AREA TONIGHT...AND IS OVER EASTERN WI BY 12Z THU. WINDS BECOME LIGHT THIS EVENING BUT APPEARS WINDS MAY STIR/INCREASE A BIT LATE TONIGHT...ESPECIALLY OVER THE WEST HALF OF THE FCST AREA. COLDEST OF THE LOW LEVEL AIRMASS IS OVER THE EAST HALF OF THE FCST AREA TONIGHT...ALONG WITH THE LIGHTEST WINDS...WITH LOWS TONIGHT FALLING INTO THE 30S...COLDEST ALONG/NORTHEAST OF I-94. CONTINUED MENTION OF FROST OVER MAINLY THE EAST 2/3 OF THE FCST AREA TONIGHT. WILL LEAVE ANY POTENTIAL FROST HEADLINES TONIGHT TO DAY CREW WHO CAN MONITOR TEMPS/DEWPOINT/WIND TRENDS THRU THE EARLY AFTERNOON HOURS. HIGH CONTINUES TO MOVE OFF THU WITH INCREASING SOUTHEAST WINDS BETWEEN IT AND THE NEXT LOW/TROUGH INTO THE CENTRAL/NORTHERN PLAINS. MID/HIGH LEVEL MOISTURE AHEAD OF THIS TROUGH SPREADS EAST ACROSS THE AREA THU WITH THE INCREASE OF LOWER LEVEL MOISTURE REACHING THE WEST END OF THE FCST AREA EITHER LATE THU AFTERNOON OR THU EVENING. DEEPER/STRONGER OF THE FORCING FROM 925-850MB WARM/MOISTURE ADVECTION/ISENTROPIC LIFT THRU PV ADVECTION/DIVERGENCE ALOFT AHEAD OF THE SHORTWAVE MOVE INTO/ACROSS THE AREA THU NIGHT. ADDED A SMALL -SHRA CHANCE TO THE WEST END OF THE FCST AREA LATE THU AFTERNOON TO BLEND WITH NEIGHBORING GRIDS. RAISED RAIN CHANCES BY LATE THU NIGHT TOWARD 80 PERCENT WITH EVEN THE LOOSE MODEL CONSENSUS ALL PRODUCING SOME PRECIP OVER THE AREA. LEANING TOWARD THE SLOWER ECMWF/GEM FOR FRI...CONTINUED 20-50 PERCENT RAIN CHANCES...HIGHEST EAST...OVER THE FCST AREA FRI MORNING. CAPE LOOKS TO REMAIN LIMITED THU NIGHT/FRI MORNING. GIVEN THE STRENGTH/DEPTH OF THE FORCING/LIFT AND MODEL SOUNDINGS SHOWING NEAR NEUTRAL STABILITY ABOVE 850MB CONTINUED MENTION OF ISOLATED OR SCT TSRA IN THE LATE THU AFTERNOON THRU FRI MORNING PERIODS. WEAK SFC-500MB RIDGING BUILDS ACROSS THE AREA FOR LATER FRI/FRI NIGHT. LEANING TOWARD THE SLOWER ECMWF/GEM...ANY RETURNING LOWER LEVEL MOISTURE TRANSPORT/WARM ADVECTION WOULD REMAIN WEST OF THE FCST AREA FRI NIGHT AND REMOVED THE SMALL -SHRA/TSRA CHANCE. WITH PLENTY OF SUNSHINE TODAY...AT LEAST OVER THE CENTRAL/SOUTH PARTS OF THE FCST AREA...FAVORED WARMER OF THE GUIDANCE HIGHS. WITH THE COOL/DRY AIRMASS OVER THE AREA...FAVORED COOLER OF GUIDANCE LOWS TONIGHT. GUIDANCE HIGHS SIMILAR AND LOOK REASONABLE FOR THU. WITH THICKER CLOUDS/-SHRA...FAVORED WARMER OF GUIDANCE LOWS THU NIGHT. WITH TIMING UNCERTAINTIES...USED A BLEND OF GUIDANCE HIGHS/ LOWS FOR FRI/FRI NIGHT. .LONG TERM...SATURDAY THROUGH TUESDAY 356 AM CDT WED MAR 28 2012 SOME IMPROVEMENT OF CONSISTENCY AMONG 28.00Z MODEL RUNS FOR SAT INTO SUN...BUT BETWEEN MODEL AND RUN-TO-RUN CONSISTENCY CONTINUES TO LEAVE A LOT TO BE DESIRED BY SUN NIGHT AND FOR EARLY NEXT WEEK. AVERAGE CONFIDENCE SAT INTO SUN WITH IMPROVING MODEL CONSENSUS INDICATING SHORTWAVE RIDGING ALOFT CROSSING THE UPPER MIDWEST. WEEKEND TRENDING TO BE DRY OR ONLY VERY SMALL -SHRA/TSRA CHANCES AND A WARMING PERIOD WITH THE RIDGING/RISING HGTS AND PERSISTENT LOW LEVEL WARM ADVECTION OVER THE REGION. WITH THE VERY LOW CONSISTENCY AMONG THE MODELS BY MON/TUE...FCST CONFIDENCE THESE PERIODS QUITE LOW AS WELL. SOME SIGNAL AMONG ALL MODELS FOR TROUGHING TO MOVE INTO/ACROSS THE UPPER MIDWEST IN THE MON/TUE TIMEFRAME BUT DETAIL DIFFERENCE QUITE LARGE. ONE OF THE MOST EXTREME SOLUTIONS FOR EARLY NEXT WEEK IS THE UKMET...WITH A LARGE NEGATIVE TILT CENTRAL CONUS TROUGH AND A 984MB SFC LOW NEAR KDBQ MON EVENING. IMPLICATIONS FOR THIS WOULD NOT GO WELL WITH OUR WARM/EARLY START TO SPRING. WITH LOW CONFIDENCE AND ALL THE MODEL SPREAD STAYED NEAR THE MODEL/ENSEMBLE CONSENSUS FOR DAYS 6/7. DID RAISE HIGHS A BIT SUNDAY WITH STRONG RIDGING/WARMING AHEAD OF ANY TROUGHING/SFC LOW FOR EARLY NEXT WEEK. && .AVIATION...THROUGH 18Z THURSDAY 1236 PM CDT WED MAR 28 2012 MAIN AVIATION FORECAST CONCERNS IS LOW PRESSURE OVER THE GREAT LAKES REGION WRAPPING STRATOCUMULUS CLOUD DECK INTO THE REGION THIS AFTERNOON AND INTO THE EARLY EVENING HOURS. CEILING HEIGHTS WITHIN THE STRATOCUMULUS DECK ARE IN THE MVFR RANGE OF 2000 TO 3500 FEET. THE COMBINATION OF ABUNDANT SUNSHINE AHEAD OF THE DECK OF CLOUDS AND SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE NORTHERN PLAINS...STRATOCUMULUS DECK IS SLOWLY ERODING ON SOUTHERN FLANK PER LATEST VISIBLE SATELLITE IMAGERY. LATEST 28.15Z RUC AND 28.12Z NAM SHOW STRATOCUMULUS DECK TO HOLD TOGETHER BEFORE ERODING LATE THIS AFTERNOON AND EARLY EVENING HOURS PER RELATIVE HUMIDITY FIELDS AT 850MB AND 925MB. FOR NOW...HAVE INTRODUCED BROKEN LAYER AT MVFR CONDITIONS AT KRST AND ADDED A TEMPO GROUP OF SCATTERED CLOUDS THROUGH 22Z WEDNESDAY. AT KLSE...CEILINGS HEIGHTS SHOULD BE ABOVE 3000 FEET AND IN THE VFR RANGE. NEXT AVIATION CONCERN IS APPROACHING COLD FRONT FOR THURSDAY. LATEST DETERMINISTIC 28.12Z MODELS SHOW PRESSURE GRADIENT TIGHTENING AND WIND DIRECTION SHIFTING TO SOUTHEAST AFTER 13Z THURSDAY. SUSTAIN WIND SPEEDS ARE EXPECTED TO BE AROUND 15 KNOTS AND GUST UP TO AROUND 20 KNOTS...ESPECIALLY AT KRST. && .ARX WATCHES/WARNINGS/ADVISORIES... 356 AM CDT WED MAR 28 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION...DTJ