Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/29/14


AREA FORECAST DISCUSSION
NWS PUEBLO CO
327 PM MDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 327 PM MDT SUN APR 27 2014 CURRENTLY...STRONG UPPER LEVEL AND SURFACE LOW PRESSURE STACKED OVER NORTHWESTERN KS WITH SOUTHERN END OF WRAP AROUND DEFORMATION PRECIP SLOWLY WEAKENING OVER SOUTHEAST CO. FARTHER WEST...LAPS SURFACE PRESSURE DATA SHOWS WEAK SECONDARY LOW PRESSURE NEAR KPUB...WHICH HAS CREATED LIGHTER WINDS OVER MUCH OF PUEBLO COUNTY THIS AFTERNOON...AND HAS IN GENERAL WEAKENED THE PRESSURE GRADIENT ACROSS SOUTHEAST COLORADO. WITH CONVECTION ENDING AND STRONG SURFACE GRADIENT LACKING...WIND SPEEDS HAVE BEGUN TO VERY SLOWLY DECREASE ACROSS THE PLAINS...AND STRONGEST GUSTS HAVE FALLEN BACK INTO THE 40- 45 KT RANGE. LATEST HRRR SUGGESTS WIND SPEEDS HAVE ALREADY PEAKED...AND GIVEN LACK OF OBSERVED 50 KT GUSTS...WILL CANCEL THE HIGH WIND WARNING FOR THE FAR SOUTHEAST. OVER THE MOUNTAINS...STILL SOME -SHSN OVER THE CONTINENTAL DIVIDE...THOUGH WEB CAMS SUGGEST LITTLE IN THE WAY OF ACCUMULATION OR LOW VISIBILITY...AT LEAST AT PASS LEVEL. TONIGHT...WILL KEEP SOME LOW POPS IN THE EVENING TO ACCOUNT FOR LINGERING -SHRA OVER THE SOUTHEAST PLAINS...WITH SOME HIGHER POPS FOR THE CENTRAL MOUNTAINS ALONG THE CONTINENTAL DIVIDE...WHERE SECONDARY UPPER WAVE WILL LIKELY HELP INCREASE -SHSN COVERAGE LATER TONIGHT. EXPECT WINDS TO GRADUALLY DIMINISH ALL AREAS THROUGH THE NIGHT...THOUGH MANY LOCATIONS WILL STAY BREEZY AS STRONG WINDS JUST OFF THE SURFACE PERSIST. EXPECTING ENOUGH IN THE WAY OF WINDS/CLOUDS TO KEEP PLAINS FROM A HARD FREEZE...THOUGH MOST MOUNTAINS AND HIGH VALLEYS WILL DROP INTO THE 20S OR COLDER. MONDAY...UPPER LOW VERY SLOWLY DRIFTS INTO ERN NEBRASKA DURING THE DAY...KEEPING STRONG NW FLOW AT THE SURFACE AND ALOFT ACROSS MOST OF SOUTHERN COLORADO. EXPECT WINDS TO INCREASE ALL AREAS BY MID MORNING...WITH GUSTS IN THE 30-40 KT RANGE MOST LOCATIONS BY AFTERNOON. GIVEN RATHER COLD AIR ALOFT/STEEP LAPSE RATES IN PLACE MON AFTERNOON...SUSPECT AT LEAST ISOLATED RAIN AND SNOW SHOWERS WILL DEVELOP OVER THE MOUNTAINS...WITH PERHAPS A FEW SPRINKLES/LIGHT SHOWERS OVER LOWER ELEVATIONS LATE IN THE DAY. LOW LEVELS WILL BE FAIRLY DRY...WHICH WILL KEEP PRECIP AMOUNTS LIGHT. MAX TEMPS WILL REMAIN COOL...WITH BLENDED NUMERICAL GUIDANCE LOOKING OK FOR HIGHS. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 327 PM MDT SUN APR 27 2014 VERY UNSETTLED PATTERN QUEUED UP FOR THE FORECAST AREA THROUGH THE EXTENDED FORECAST...BUT MODELS ARE LEANING TOWARDS TWO SEPARATE PERIODS OF WEATHER TYPES. MONDAY NIGHT THROUGH THURSDAY...LONG RANGE MODELS INDICATE THAT THE UPPER LOW PRESSURE SYSTEM WILL PINWHEEL ABOUT THE US CENTRAL PLAINS AND UPPER MISSISSIPPI RIVER VALLEY THROUGH THU...BEFORE FINALLY EJECTING TO THE NE ACROSS THE GREAT LAKES. THIS SOLUTION WILL KEEP VERY BRISK AND COOL NORTHERLY FLOW IN PLACE FOR THE STATE INTO THU...AS WELL AS A DAILY SHOT OF SHOWER ACTIVITY FOR THE CWA. AS THE LOW LINGERS...LOBES OF ENERGY WILL ROTATE AROUND THE SYSTEM AND BRING PERIODICALLY BETTER CHANCES FOR SHOWERS...THOUGH THE EXACT TIMING OF THESE WINDOWS IS NEAR IMPOSSIBLE TO PREDICT AT THIS TIME. LOOK FOR MAX TEMPS EACH DAY IN THE 50S TO AROUND 60 F FOR THE LOWER ELEVATIONS...AND 30S TO 40S FOR THE MTS. THE HIGHER TERRAIN IS EXPECTED TO EXPERIENCE ISOLATED TO LOW END SCATTERED POPS THROUGH THU...WITH THE BEST SHOT OF SOME ISOLATED CONVECTION FOR THE PLAINS COMING TUE AFTN...AND AGAIN WED AFTN AND EVE. FRIDAY THROUGH SUNDAY...THE GFS AND EC MODELS HINT THAT BY FRI THE UPPER LOW WILL FINALLY BE PULLING AWAY FROM THE REGION...ALLOWING THE UPPER FLOW TO SHIFT TO A MORE WESTERLY DIRECTION INTO THE WEEKEND. BOTH MODELS DO CONTINUE TO SHOW MEAGER SHOWER ACTIVITY BOTH FRI AND SAT...MAINLY TIED TO THE HIGHER TERRAIN...BUT FEEL THAT THIS FAR OUT THIS MAY BE A BIT OVERDONE. BY SUNDAY PCPN SHOULD COME TO AN END. LOOK FOR A WARMING TREND INTO THE WEEKEND AS THE UPPER FLOW SHIFTS...WITH MAX TEMPS IN THE 60S FOR FRI...THEN 70S FOR BOTH SAT AND SUN. MOORE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 327 PM MDT SUN APR 27 2014 EXPECT VFR CONDITIONS ALL TAF SITES TONIGHT AND MONDAY. GUSTY WINDS AT KCOS AND KALS WILL GRADUALLY DIMINISH AFTER 02Z...THOUGH W-NW WINDS IN THE 10-15 KT RANGE MAY PERSIST THROUGH THE NIGHT. ON MON...NW WINDS WILL INCREASE QUICKLY DURING THE MORNING...WITH GUSTS TO 25 KTS ALL TERMINALS BY 16Z...THEN A FEW GUSTS IN THE 30-35 KT BY 20Z. MAY SEE SOME VIRGA/-SHRA OVER THE MOUNTAINS DRIFT TOWARD KCOS AND KALS AFTER 20Z AS WELL...THOUGH NOT EXPECTING ANY CIG/VIS RESTRICTIONS. OVER THE MOUNTAINS...-SHSN WILL PERSIST THROUGH THE NIGHT...ESPECIALLY NORTH OF MONARCH PASS...WHERE AREAS OF IFR CONDITIONS WILL BE POSSIBLE THROUGH 12Z. ON MON...SHOWERS WILL REDEVELOP WITH PEAKS BECOMING OBSCURED MANY AREAS AFTER 18Z. OVER THE PLAINS...-SHRA WILL CONTINUE TO DIMINISH THROUGH THE EVENING WITH VFR CONDITIONS ALL AREAS BY 02Z. WINDS WILL ALSO SLOWLY DIMINISH THROUGH THE EVENING. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PETERSEN LONG TERM...MOORE AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1203 PM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 1201 PM MDT SUN APR 27 2014 WILL LET WINTER STORM WARNING EXPIRE FOR AREAS ALONG THE CONTINENTAL DIVIDE AS WEB CAMS SUGGEST ONLY VERY LIGHT SNOW LINGERING AS OF NOON...AND LITTLE OR NO ACCUMULATION EXPECTED FOR THE REMAINDER OF THE DAY. UPDATE ISSUED AT 1038 AM MDT SUN APR 27 2014 APPEARS CONVECTION HAS ALLOWED BAND OF HIGHER WINDS ALOFT TO REACH THE SURFACE OVER THE FAR SOUTHEAST PLAINS...WITH GUSTS TO 50 KTS AT KLAA. WILL ISSUE A HIGH WIND WARNING THROUGH THE AFTERNOON TO COVER THREAT OF STRONG GUSTS AS MAIN BAND OF WRAP AROUND PRECIP MOVES EAST THROUGH THE REGION. SOME REPORTS OF LOW VIS IN BLOWING DUST AS WELL...BUT WITH RAIN MOVING TOWARD THE AREA WON`T ISSUE ANY DUST HIGHLIGHTS FOR NOW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM MDT SUN APR 27 2014 CURRENTLY...STRONG UPPER LEVEL LOW PRESSURE CENTER IS CURRENTLY SITTING OVER SOUTHEAST COLORADO. RADAR IS STARTING TO LIGHT UP ALONG THE PALMER DIVIDE...SOUTH ALONG THE I-25 CORRIDOR TO PUEBLO. A FEW LIGHTNING STRIKES ARE ALSO BEING SEEN WITH THIS ACTIVITY. TEMPERATURES ARE COOL...WITH GENERALLY 30S TO 40S UNDER THE DEVELOPING PRECIPITATION. OUT EAST AHEAD OF THE PRECIPITATION ITS CURRENTLY IN THE 50S. GUSTY NORTH WINDS HAVE FILTERED INTO THE PALMER DIVIDE REGION AND SHOULD ONLY STRENGTHEN AND SPREAD ACROSS THE PLAINS THROUGH THE EARLY MORNING HOURS. IT IS ALSO CURRENTLY SNOWING ACROSS THE HIGHER ELEVATIONS...WITH AREA WEBCAMS INDICATING SNOW LEVELS STILL ABOVE 9 TO 10 KFT. TODAY...MODELS ALL IN DECENT AGREEMENT WITH THE UPPER LEVEL LOW SHIFTING NORTHEAST INTO SOUTH CENTRAL NEBRASKA BY THIS AFTERNOON. FOLLOWED A BLEND OF THE RAP AND HRRR HIGH RES MODEL SOLUTIONS AS FAR AS EVOLUTION OF THE STORM SYSTEM. ALL SOLUTIONS ARE DEVELOPING A TROWAL...WHICH IS IN ITS FORMATION STAGE EARLY THIS MORNING...AND TRACKING IT EAST ACROSS THE PLAINS THROUGH THE AFTERNOON AND EXITING KIOWA COUNTY BY SUNSET. UNDER THE TROWAL PRECIPITATION BAND...EXPECT TO SEE PERIODS OF LIGHT TO MODERATE RAINFALL ALONG WITH A FEW THUNDERSTORMS. THE MAIN THREAT FROM THUNDERSTORMS WILL BE LIGHTNING. MOST AREAS ACROSS THE PLAINS...ESPECIALLY AREAS NORTH OF HIGHWAY 50...WILL SEE WETTING RAINS...WITH AROUND ONE TO TWO TENTHS OF AN INCH OF PRECIPITATION. SNOW LEVELS REMAIN TRICKY. THE STORM SYSTEM IS QUITE WARM AND SUGGESTS SNOW LEVELS REMAINING AROUND 9 KFT. HOWEVER...THE CONVECTIVE NATURE OF THE SHOWER ACTIVITY WILL LIKELY FORCE SNOW LEVELS DOWN...ESPECIALLY OVER TELLER COUNTY AND THE PALMER DIVIDE...TO NEAR 8 TO 7 KFT. GIVEN THE WARM GROUND SURFACE TEMPERATURES...WE WILL LIKELY NOT SEE MUCH IN THE WAY OF ACCUMULATIONS OVER THE PALMER DIVIDE. UP IN THE MOUNTAINS ABOVE 9 KFT THERE WILL LIKELY BE A SOLID 6 TO 10 INCHES OF SNOW ALONG THE CONTINENTAL DIVIDE...WHILE AREAS OF THE EASTERN MOUNTAINS SEE AROUND 3 TO 6 INCHES. THE OTHER MAIN FORECAST ISSUE FOR THIS AFTERNOON WILL BE THE WINDS. A STRONG PRESSURE GRADIENT AROUND THE UPPER LEVEL STORM SYSTEM WILL HELP TO GENERATE STRONG NORTH TO NORTHWEST WINDS ACROSS EASTERN COLORADO FOR THIS AFTERNOON. MODEL GUIDANCE SUGGESTS SUSTAINED WINDS APPROACHING 30 KTS WITH GUSTS IN EXCESS OF 50 KTS POSSIBLE. THIS WILL LEAD TO DANGEROUS DRIVING CONDITIONS DUE TO STRONG CROSS WINDS ON EAST-WEST HIGHWAYS. ANY LOOSE OUTDOOR ITEMS SUCH AS PLANTS AND LAWN FURNITURE SHOULD BE BROUGHT INDOORS. TONIGHT...THE UPPER LEVEL STORM SYSTEM WILL CONTINUE TO DRIFT NORTH ACROSS CENTRAL NEBRASKA. THIS WILL KEEP THE REGION UNDER STRONG NORTHERLY FLOW. MODELS ALL IN GOOD AGREEMENT WITH PRECIPITATION COMING TO AN END ACROSS THE PLAINS AROUND 00Z/MON AND FOLLOWED THIS TREND IN THE FORECAST. LIGHT SNOW SHOWERS WILL LIKELY CONTINUE ALONG THE CONTINENTAL DIVIDE TONIGHT WITH THE CENTRAL MOUNTAINS FAVORED DUE TO NORTHWESTERLY OROGRAPHIC UPSLOPE FLOW. TEMPERATURES WILL BE COOL TONIGHT WITH LOWER TO MID 30S EXPECTED FOR THE LOWER ELEVATIONS. GIVEN THE NEAR FREEZING TEMPERATURES...THOSE WITH SENSITIVE OUTDOOR PLANTS SHOULD TAKE PRECAUTIONS TO PROTECT THEM. MOZLEY .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM MDT SUN APR 27 2014 ...CONTINUED COOL AND UNSETTLED... MODELS IN FAIRLY GOOD AGREEMENT WITH THE TRACK OF THE UPPER LOW THROUGH -----...AS IT MAKES SLOW PROGRESS ACROSS THE CENTRAL PLAINS BEFORE GRADUALLY LIFTING TO THE NORTHEAST INTO IA AND MN BY TUESDAY AFTERNOON. TRAILING ENERGY DROPPING DOWN THE WESTERN SIDE OF THE UPPER LOW WILL KEEP UNSETTLED WEATHER OVER THE REGION...ESPECIALLY ALONG THE CONTINENTAL DIVIDE WHERE PERIODIC LIGHT SNOW WILL CONTINUE...AND ACROSS NORTHERN AND EASTERN PORTIONS OF THE SOUTHEAST PLAINS AS ANOTHER LOBE OF ENERGY ROTATES GLANCES BY THE SOUTHEAST PLAINS ALONG THE WESTERN PERIPHERY OF THE UPPER LOW. OVERALL...ACCUMULATIONS REMAIN LIGHT AT THIS POINT. COULD BE FLIRTING WITH CRITICAL FIRE WEATHER CONDITIONS ON MONDAY ACROSS THE SOUTHEAST PLAINS WHERE WINDS WILL REMAIN QUITE STRONG...THOUGH WITH THE COOLER TEMPERATURES...DEW POINTS MAY NOT BE QUITE LOW ENOUGH TO HIT THE 3 HOUR WINDOW OF 15 PERCENT...SO NO FIRE WEATHER HIGHLIGHTS LOOK NECESSARY AT THIS POINT. TEMPERATURES WILL REMAIN BELOW NORMAL AND OVERNIGHT LOWS MONDAY NIGHT AND AGAIN TUESDAY NIGHT WILL STILL COME CLOSE OR HIT THE FREEZING MARK ACROSS THE SOUTHEAST PLAINS. TOO EARLY IN THE GROWING SEASON FOR FROST/FREEZE HIGHLIGHTS AS THESE DO NOT START UNTIL MAY 1ST. A REINFORCING SURGE OF COLD AIR DROPS THROUGH THE SOUTHEAST PLAINS TUESDAY NIGHT. WINDS AND CLOUDS BEHIND THIS MAY HELP KEEP TEMPERATURES SLIGHTLY ABOVE FREEZING ACROSS PORTIONS OF THE PLAINS. HOWEVER...MODELS DIFFER WITH QPF TUESDAY NIGHT...WITH GFS THE WETTEST MODEL...PRINTING 2-4 INCHES OF SNOW FOR THE SOUTHEAST MOUNTAINS. ECMWF ALSO SHOWS SOME SNOW FOR THE SE MTS/ADJACENT PLAINS...BUT IS MUCH LIGHTER...WHILE NAM IS VIRTUALLY DRY. FORECAST LEANS MORE TOWARDS THE ECMWF FOR NOW AS IT IS A NICE COMPROMISE. ANOTHER SHORTWAVE DROPS DOWN THE WESTERN SIDE OF THE BROAD UPPER LOW ACROSS CO ON WEDNESDAY. GFS AND ECMWF PULL THE H7 WINDS A LITTLE MORE OUT OF THE NORTHEAST PERHAPS GIVING THE SE MTS ANOTHER SHOT OF SOME SNOW. GFS IS MUCH HEAVIER THAN EC WITH QPF...SO UNCERTAINTY REMAINS HIGH. UPPER LOW PULLS AWAY TO THE NORTHWEST BY LATE IN THE WEEK...WITH FLOW ALOFT GRADUALLY BECOMING MORE WESTERLY WITH TIME. THIS WILL BODE FOR A GRADUAL WARM UP...THOUGH ECMWF BRINGS ANOTHER FRONT THROUGH THE SOUTHEAST PLAINS FRI NIGHT...WHICH GFS KEEPS WELL TO THE NORTH AND EAST. TOO SOON TO SAY WITH CONFIDENCE...SO HAVE TAPERED BACK THE WARM UP A FEW DEGREES. -KT && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1122 AM MDT SUN APR 27 2014 MAINLY VFR AT TAF SITES TODAY AND TONIGHT...THOUGH A FEW -SHRA BRUSH BY JUST EAST OF KCOS IN THE 18Z-20Z TIME PERIOD. MAIN STORY TODAY WILL BE STRONG N-NW WINDS...AS SURFACE AND UPPER LEVEL LOW PRESSURE REMAINS OVER WESTERN KS THROUGH THE DAY. EXPECT GUSTS IN THE 35-45 KT RANGE AT KCOS UNTIL 00Z-02Z...30-40 KTS AT KALS AND KPUB. WINDS WILL GRADUALLY DIMINISH AFTER SUNSET...THOUGH SPEEDS WILL REMAIN IN THE 10-20 KNOT RANGE MOST OF THE NIGHT. WITH UPPER LOW VERY SLOW TO MOVE AWAY FROM THE AREA MONDAY...EXPECT STRONG W-NW WINDS ONCE AGAIN...WITH GUSTS TO 25 KNOTS ALL TAF SITES BY 15Z-16Z. OVER THE MTS...PRECIP SLOWLY DIMINISHING LATE THIS MORNING...AND EXPECT GRADUALLY IMPROVING CONDITIONS FOR THE REMAINDER OF THE DAY. ON THE PLAINS...BAND OF -SHRA/-TSRA AND MVFR CIGS/VIS WILL CONTINUE TO SHIFT EASTWARD THROUGH 22Z...THEN GRADUALLY MOVE INTO KS BY 00Z. && .PUB WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ095>099. && $$ UPDATE...PETERSEN SHORT TERM...MOZLEY LONG TERM...KT AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1132 AM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 1038 AM MDT SUN APR 27 2014 APPEARS CONVECTION HAS ALLOWED BAND OF HIGHER WINDS ALOFT TO REACH THE SURFACE OVER THE FAR SOUTHEAST PLAINS...WITH GUSTS TO 50 KTS AT KLAA. WILL ISSUE A HIGH WIND WARNING THROUGH THE AFTERNOON TO COVER THREAT OF STRONG GUSTS AS MAIN BAND OF WRAP AROUND PRECIP MOVES EAST THROUGH THE REGION. SOME REPORTS OF LOW VIS IN BLOWING DUST AS WELL...BUT WITH RAIN MOVING TOWARD THE AREA WON`T ISSUE ANY DUST HIGHLIGHTS FOR NOW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM MDT SUN APR 27 2014 CURRENTLY...STRONG UPPER LEVEL LOW PRESSURE CENTER IS CURRENTLY SITTING OVER SOUTHEAST COLORADO. RADAR IS STARTING TO LIGHT UP ALONG THE PALMER DIVIDE...SOUTH ALONG THE I-25 CORRIDOR TO PUEBLO. A FEW LIGHTNING STRIKES ARE ALSO BEING SEEN WITH THIS ACTIVITY. TEMPERATURES ARE COOL...WITH GENERALLY 30S TO 40S UNDER THE DEVELOPING PRECIPITATION. OUT EAST AHEAD OF THE PRECIPITATION ITS CURRENTLY IN THE 50S. GUSTY NORTH WINDS HAVE FILTERED INTO THE PALMER DIVIDE REGION AND SHOULD ONLY STRENGTHEN AND SPREAD ACROSS THE PLAINS THROUGH THE EARLY MORNING HOURS. IT IS ALSO CURRENTLY SNOWING ACROSS THE HIGHER ELEVATIONS...WITH AREA WEBCAMS INDICATING SNOW LEVELS STILL ABOVE 9 TO 10 KFT. TODAY...MODELS ALL IN DECENT AGREEMENT WITH THE UPPER LEVEL LOW SHIFTING NORTHEAST INTO SOUTH CENTRAL NEBRASKA BY THIS AFTERNOON. FOLLOWED A BLEND OF THE RAP AND HRRR HIGH RES MODEL SOLUTIONS AS FAR AS EVOLUTION OF THE STORM SYSTEM. ALL SOLUTIONS ARE DEVELOPING A TROWAL...WHICH IS IN ITS FORMATION STAGE EARLY THIS MORNING...AND TRACKING IT EAST ACROSS THE PLAINS THROUGH THE AFTERNOON AND EXITING KIOWA COUNTY BY SUNSET. UNDER THE TROWAL PRECIPITATION BAND...EXPECT TO SEE PERIODS OF LIGHT TO MODERATE RAINFALL ALONG WITH A FEW THUNDERSTORMS. THE MAIN THREAT FROM THUNDERSTORMS WILL BE LIGHTNING. MOST AREAS ACROSS THE PLAINS...ESPECIALLY AREAS NORTH OF HIGHWAY 50...WILL SEE WETTING RAINS...WITH AROUND ONE TO TWO TENTHS OF AN INCH OF PRECIPITATION. SNOW LEVELS REMAIN TRICKY. THE STORM SYSTEM IS QUITE WARM AND SUGGESTS SNOW LEVELS REMAINING AROUND 9 KFT. HOWEVER...THE CONVECTIVE NATURE OF THE SHOWER ACTIVITY WILL LIKELY FORCE SNOW LEVELS DOWN...ESPECIALLY OVER TELLER COUNTY AND THE PALMER DIVIDE...TO NEAR 8 TO 7 KFT. GIVEN THE WARM GROUND SURFACE TEMPERATURES...WE WILL LIKELY NOT SEE MUCH IN THE WAY OF ACCUMULATIONS OVER THE PALMER DIVIDE. UP IN THE MOUNTAINS ABOVE 9 KFT THERE WILL LIKELY BE A SOLID 6 TO 10 INCHES OF SNOW ALONG THE CONTINENTAL DIVIDE...WHILE AREAS OF THE EASTERN MOUNTAINS SEE AROUND 3 TO 6 INCHES. THE OTHER MAIN FORECAST ISSUE FOR THIS AFTERNOON WILL BE THE WINDS. A STRONG PRESSURE GRADIENT AROUND THE UPPER LEVEL STORM SYSTEM WILL HELP TO GENERATE STRONG NORTH TO NORTHWEST WINDS ACROSS EASTERN COLORADO FOR THIS AFTERNOON. MODEL GUIDANCE SUGGESTS SUSTAINED WINDS APPROACHING 30 KTS WITH GUSTS IN EXCESS OF 50 KTS POSSIBLE. THIS WILL LEAD TO DANGEROUS DRIVING CONDITIONS DUE TO STRONG CROSS WINDS ON EAST-WEST HIGHWAYS. ANY LOOSE OUTDOOR ITEMS SUCH AS PLANTS AND LAWN FURNITURE SHOULD BE BROUGHT INDOORS. TONIGHT...THE UPPER LEVEL STORM SYSTEM WILL CONTINUE TO DRIFT NORTH ACROSS CENTRAL NEBRASKA. THIS WILL KEEP THE REGION UNDER STRONG NORTHERLY FLOW. MODELS ALL IN GOOD AGREEMENT WITH PRECIPITATION COMING TO AN END ACROSS THE PLAINS AROUND 00Z/MON AND FOLLOWED THIS TREND IN THE FORECAST. LIGHT SNOW SHOWERS WILL LIKELY CONTINUE ALONG THE CONTINENTAL DIVIDE TONIGHT WITH THE CENTRAL MOUNTAINS FAVORED DUE TO NORTHWESTERLY OROGRAPHIC UPSLOPE FLOW. TEMPERATURES WILL BE COOL TONIGHT WITH LOWER TO MID 30S EXPECTED FOR THE LOWER ELEVATIONS. GIVEN THE NEAR FREEZING TEMPERATURES...THOSE WITH SENSITIVE OUTDOOR PLANTS SHOULD TAKE PRECAUTIONS TO PROTECT THEM. MOZLEY .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM MDT SUN APR 27 2014 ...CONTINUED COOL AND UNSETTLED... MODELS IN FAIRLY GOOD AGREEMENT WITH THE TRACK OF THE UPPER LOW THROUGH -----...AS IT MAKES SLOW PROGRESS ACROSS THE CENTRAL PLAINS BEFORE GRADUALLY LIFTING TO THE NORTHEAST INTO IA AND MN BY TUESDAY AFTERNOON. TRAILING ENERGY DROPPING DOWN THE WESTERN SIDE OF THE UPPER LOW WILL KEEP UNSETTLED WEATHER OVER THE REGION...ESPECIALLY ALONG THE CONTINENTAL DIVIDE WHERE PERIODIC LIGHT SNOW WILL CONTINUE...AND ACROSS NORTHERN AND EASTERN PORTIONS OF THE SOUTHEAST PLAINS AS ANOTHER LOBE OF ENERGY ROTATES GLANCES BY THE SOUTHEAST PLAINS ALONG THE WESTERN PERIPHERY OF THE UPPER LOW. OVERALL...ACCUMULATIONS REMAIN LIGHT AT THIS POINT. COULD BE FLIRTING WITH CRITICAL FIRE WEATHER CONDITIONS ON MONDAY ACROSS THE SOUTHEAST PLAINS WHERE WINDS WILL REMAIN QUITE STRONG...THOUGH WITH THE COOLER TEMPERATURES...DEW POINTS MAY NOT BE QUITE LOW ENOUGH TO HIT THE 3 HOUR WINDOW OF 15 PERCENT...SO NO FIRE WEATHER HIGHLIGHTS LOOK NECESSARY AT THIS POINT. TEMPERATURES WILL REMAIN BELOW NORMAL AND OVERNIGHT LOWS MONDAY NIGHT AND AGAIN TUESDAY NIGHT WILL STILL COME CLOSE OR HIT THE FREEZING MARK ACROSS THE SOUTHEAST PLAINS. TOO EARLY IN THE GROWING SEASON FOR FROST/FREEZE HIGHLIGHTS AS THESE DO NOT START UNTIL MAY 1ST. A REINFORCING SURGE OF COLD AIR DROPS THROUGH THE SOUTHEAST PLAINS TUESDAY NIGHT. WINDS AND CLOUDS BEHIND THIS MAY HELP KEEP TEMPERATURES SLIGHTLY ABOVE FREEZING ACROSS PORTIONS OF THE PLAINS. HOWEVER...MODELS DIFFER WITH QPF TUESDAY NIGHT...WITH GFS THE WETTEST MODEL...PRINTING 2-4 INCHES OF SNOW FOR THE SOUTHEAST MOUNTAINS. ECMWF ALSO SHOWS SOME SNOW FOR THE SE MTS/ADJACENT PLAINS...BUT IS MUCH LIGHTER...WHILE NAM IS VIRTUALLY DRY. FORECAST LEANS MORE TOWARDS THE ECMWF FOR NOW AS IT IS A NICE COMPROMISE. ANOTHER SHORTWAVE DROPS DOWN THE WESTERN SIDE OF THE BROAD UPPER LOW ACROSS CO ON WEDNESDAY. GFS AND ECMWF PULL THE H7 WINDS A LITTLE MORE OUT OF THE NORTHEAST PERHAPS GIVING THE SE MTS ANOTHER SHOT OF SOME SNOW. GFS IS MUCH HEAVIER THAN EC WITH QPF...SO UNCERTAINTY REMAINS HIGH. UPPER LOW PULLS AWAY TO THE NORTHWEST BY LATE IN THE WEEK...WITH FLOW ALOFT GRADUALLY BECOMING MORE WESTERLY WITH TIME. THIS WILL BODE FOR A GRADUAL WARM UP...THOUGH ECMWF BRINGS ANOTHER FRONT THROUGH THE SOUTHEAST PLAINS FRI NIGHT...WHICH GFS KEEPS WELL TO THE NORTH AND EAST. TOO SOON TO SAY WITH CONFIDENCE...SO HAVE TAPERED BACK THE WARM UP A FEW DEGREES. -KT && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1122 AM MDT SUN APR 27 2014 MAINLY VFR AT TAF SITES TODAY AND TONIGHT...THOUGH A FEW -SHRA BRUSH BY JUST EAST OF KCOS IN THE 18Z-20Z TIME PERIOD. MAIN STORY TODAY WILL BE STRONG N-NW WINDS...AS SURFACE AND UPPER LEVEL LOW PRESSURE REMAINS OVER WESTERN KS THROUGH THE DAY. EXPECT GUSTS IN THE 35-45 KT RANGE AT KCOS UNTIL 00Z-02Z...30-40 KTS AT KALS AND KPUB. WINDS WILL GRADUALLY DIMINISH AFTER SUNSET...THOUGH SPEEDS WILL REMAIN IN THE 10-20 KNOT RANGE MOST OF THE NIGHT. WITH UPPER LOW VERY SLOW TO MOVE AWAY FROM THE AREA MONDAY...EXPECT STRONG W-NW WINDS ONCE AGAIN...WITH GUSTS TO 25 KNOTS ALL TAF SITES BY 15Z-16Z. OVER THE MTS...PRECIP SLOWLY DIMINISHING LATE THIS MORNING...AND EXPECT GRADUALLY IMPROVING CONDITIONS FOR THE REMAINDER OF THE DAY. ON THE PLAINS...BAND OF -SHRA/-TSRA AND MVFR CIGS/VIS WILL CONTINUE TO SHIFT EASTWARD THROUGH 22Z...THEN GRADUALLY MOVE INTO KS BY 00Z. && .PUB WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ095>099. WINTER STORM WARNING UNTIL NOON MDT TODAY FOR COZ058-060-061-066- 068. && $$ UPDATE...PETERSEN SHORT TERM...MOZLEY LONG TERM...KT AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1044 AM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 1038 AM MDT SUN APR 27 2014 APPEARS CONVECTION HAS ALLOWED BAND OF HIGHER WINDS ALOFT TO REACH THE SURFACE OVER THE FAR SOUTHEAST PLAINS...WITH GUSTS TO 50 KTS AT KLAA. WILL ISSUE A HIGH WIND WARNING THROUGH THE AFTERNOON TO COVER THREAT OF STRONG GUSTS AS MAIN BAND OF WRAP AROUND PRECIP MOVES EAST THROUGH THE REGION. SOME REPORTS OF LOW VIS IN BLOWING DUST AS WELL...BUT WITH RAIN MOVING TOWARD THE AREA WON`T ISSUE ANY DUST HIGHLIGHTS FOR NOW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM MDT SUN APR 27 2014 CURRENTLY...STRONG UPPER LEVEL LOW PRESSURE CENTER IS CURRENTLY SITTING OVER SOUTHEAST COLORADO. RADAR IS STARTING TO LIGHT UP ALONG THE PALMER DIVIDE...SOUTH ALONG THE I-25 CORRIDOR TO PUEBLO. A FEW LIGHTNING STRIKES ARE ALSO BEING SEEN WITH THIS ACTIVITY. TEMPERATURES ARE COOL...WITH GENERALLY 30S TO 40S UNDER THE DEVELOPING PRECIPITATION. OUT EAST AHEAD OF THE PRECIPITATION ITS CURRENTLY IN THE 50S. GUSTY NORTH WINDS HAVE FILTERED INTO THE PALMER DIVIDE REGION AND SHOULD ONLY STRENGTHEN AND SPREAD ACROSS THE PLAINS THROUGH THE EARLY MORNING HOURS. IT IS ALSO CURRENTLY SNOWING ACROSS THE HIGHER ELEVATIONS...WITH AREA WEBCAMS INDICATING SNOW LEVELS STILL ABOVE 9 TO 10 KFT. TODAY...MODELS ALL IN DECENT AGREEMENT WITH THE UPPER LEVEL LOW SHIFTING NORTHEAST INTO SOUTH CENTRAL NEBRASKA BY THIS AFTERNOON. FOLLOWED A BLEND OF THE RAP AND HRRR HIGH RES MODEL SOLUTIONS AS FAR AS EVOLUTION OF THE STORM SYSTEM. ALL SOLUTIONS ARE DEVELOPING A TROWAL...WHICH IS IN ITS FORMATION STAGE EARLY THIS MORNING...AND TRACKING IT EAST ACROSS THE PLAINS THROUGH THE AFTERNOON AND EXITING KIOWA COUNTY BY SUNSET. UNDER THE TROWAL PRECIPITATION BAND...EXPECT TO SEE PERIODS OF LIGHT TO MODERATE RAINFALL ALONG WITH A FEW THUNDERSTORMS. THE MAIN THREAT FROM THUNDERSTORMS WILL BE LIGHTNING. MOST AREAS ACROSS THE PLAINS...ESPECIALLY AREAS NORTH OF HIGHWAY 50...WILL SEE WETTING RAINS...WITH AROUND ONE TO TWO TENTHS OF AN INCH OF PRECIPITATION. SNOW LEVELS REMAIN TRICKY. THE STORM SYSTEM IS QUITE WARM AND SUGGESTS SNOW LEVELS REMAINING AROUND 9 KFT. HOWEVER...THE CONVECTIVE NATURE OF THE SHOWER ACTIVITY WILL LIKELY FORCE SNOW LEVELS DOWN...ESPECIALLY OVER TELLER COUNTY AND THE PALMER DIVIDE...TO NEAR 8 TO 7 KFT. GIVEN THE WARM GROUND SURFACE TEMPERATURES...WE WILL LIKELY NOT SEE MUCH IN THE WAY OF ACCUMULATIONS OVER THE PALMER DIVIDE. UP IN THE MOUNTAINS ABOVE 9 KFT THERE WILL LIKELY BE A SOLID 6 TO 10 INCHES OF SNOW ALONG THE CONTINENTAL DIVIDE...WHILE AREAS OF THE EASTERN MOUNTAINS SEE AROUND 3 TO 6 INCHES. THE OTHER MAIN FORECAST ISSUE FOR THIS AFTERNOON WILL BE THE WINDS. A STRONG PRESSURE GRADIENT AROUND THE UPPER LEVEL STORM SYSTEM WILL HELP TO GENERATE STRONG NORTH TO NORTHWEST WINDS ACROSS EASTERN COLORADO FOR THIS AFTERNOON. MODEL GUIDANCE SUGGESTS SUSTAINED WINDS APPROACHING 30 KTS WITH GUSTS IN EXCESS OF 50 KTS POSSIBLE. THIS WILL LEAD TO DANGEROUS DRIVING CONDITIONS DUE TO STRONG CROSS WINDS ON EAST-WEST HIGHWAYS. ANY LOOSE OUTDOOR ITEMS SUCH AS PLANTS AND LAWN FURNITURE SHOULD BE BROUGHT INDOORS. TONIGHT...THE UPPER LEVEL STORM SYSTEM WILL CONTINUE TO DRIFT NORTH ACROSS CENTRAL NEBRASKA. THIS WILL KEEP THE REGION UNDER STRONG NORTHERLY FLOW. MODELS ALL IN GOOD AGREEMENT WITH PRECIPITATION COMING TO AN END ACROSS THE PLAINS AROUND 00Z/MON AND FOLLOWED THIS TREND IN THE FORECAST. LIGHT SNOW SHOWERS WILL LIKELY CONTINUE ALONG THE CONTINENTAL DIVIDE TONIGHT WITH THE CENTRAL MOUNTAINS FAVORED DUE TO NORTHWESTERLY OROGRAPHIC UPSLOPE FLOW. TEMPERATURES WILL BE COOL TONIGHT WITH LOWER TO MID 30S EXPECTED FOR THE LOWER ELEVATIONS. GIVEN THE NEAR FREEZING TEMPERATURES...THOSE WITH SENSITIVE OUTDOOR PLANTS SHOULD TAKE PRECAUTIONS TO PROTECT THEM. MOZLEY .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM MDT SUN APR 27 2014 ...CONTINUED COOL AND UNSETTLED... MODELS IN FAIRLY GOOD AGREEMENT WITH THE TRACK OF THE UPPER LOW THROUGH -----...AS IT MAKES SLOW PROGRESS ACROSS THE CENTRAL PLAINS BEFORE GRADUALLY LIFTING TO THE NORTHEAST INTO IA AND MN BY TUESDAY AFTERNOON. TRAILING ENERGY DROPPING DOWN THE WESTERN SIDE OF THE UPPER LOW WILL KEEP UNSETTLED WEATHER OVER THE REGION...ESPECIALLY ALONG THE CONTINENTAL DIVIDE WHERE PERIODIC LIGHT SNOW WILL CONTINUE...AND ACROSS NORTHERN AND EASTERN PORTIONS OF THE SOUTHEAST PLAINS AS ANOTHER LOBE OF ENERGY ROTATES GLANCES BY THE SOUTHEAST PLAINS ALONG THE WESTERN PERIPHERY OF THE UPPER LOW. OVERALL...ACCUMULATIONS REMAIN LIGHT AT THIS POINT. COULD BE FLIRTING WITH CRITICAL FIRE WEATHER CONDITIONS ON MONDAY ACROSS THE SOUTHEAST PLAINS WHERE WINDS WILL REMAIN QUITE STRONG...THOUGH WITH THE COOLER TEMPERATURES...DEW POINTS MAY NOT BE QUITE LOW ENOUGH TO HIT THE 3 HOUR WINDOW OF 15 PERCENT...SO NO FIRE WEATHER HIGHLIGHTS LOOK NECESSARY AT THIS POINT. TEMPERATURES WILL REMAIN BELOW NORMAL AND OVERNIGHT LOWS MONDAY NIGHT AND AGAIN TUESDAY NIGHT WILL STILL COME CLOSE OR HIT THE FREEZING MARK ACROSS THE SOUTHEAST PLAINS. TOO EARLY IN THE GROWING SEASON FOR FROST/FREEZE HIGHLIGHTS AS THESE DO NOT START UNTIL MAY 1ST. A REINFORCING SURGE OF COLD AIR DROPS THROUGH THE SOUTHEAST PLAINS TUESDAY NIGHT. WINDS AND CLOUDS BEHIND THIS MAY HELP KEEP TEMPERATURES SLIGHTLY ABOVE FREEZING ACROSS PORTIONS OF THE PLAINS. HOWEVER...MODELS DIFFER WITH QPF TUESDAY NIGHT...WITH GFS THE WETTEST MODEL...PRINTING 2-4 INCHES OF SNOW FOR THE SOUTHEAST MOUNTAINS. ECMWF ALSO SHOWS SOME SNOW FOR THE SE MTS/ADJACENT PLAINS...BUT IS MUCH LIGHTER...WHILE NAM IS VIRTUALLY DRY. FORECAST LEANS MORE TOWARDS THE ECMWF FOR NOW AS IT IS A NICE COMPROMISE. ANOTHER SHORTWAVE DROPS DOWN THE WESTERN SIDE OF THE BROAD UPPER LOW ACROSS CO ON WEDNESDAY. GFS AND ECMWF PULL THE H7 WINDS A LITTLE MORE OUT OF THE NORTHEAST PERHAPS GIVING THE SE MTS ANOTHER SHOT OF SOME SNOW. GFS IS MUCH HEAVIER THAN EC WITH QPF...SO UNCERTAINTY REMAINS HIGH. UPPER LOW PULLS AWAY TO THE NORTHWEST BY LATE IN THE WEEK...WITH FLOW ALOFT GRADUALLY BECOMING MORE WESTERLY WITH TIME. THIS WILL BODE FOR A GRADUAL WARM UP...THOUGH ECMWF BRINGS ANOTHER FRONT THROUGH THE SOUTHEAST PLAINS FRI NIGHT...WHICH GFS KEEPS WELL TO THE NORTH AND EAST. TOO SOON TO SAY WITH CONFIDENCE...SO HAVE TAPERED BACK THE WARM UP A FEW DEGREES. -KT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 349 AM MDT SUN APR 27 2014 KALS...A FEW SNOW SHOWERS HAVE MOVED ACROSS THE SAN LUIS VALLEY THIS MORNING. MOST OF THE ACTIVITY SHOULD BE DIMINISHING THROUGH 16Z WITH LIMITED IMPACTS TO THE TERMINAL. STRONG WINDS ARE FORECAST TO DEVELOP FOR THIS AFTERNOON WITH WESTERLY GUSTS TO NEAR 35 KTS LIKELY. WINDS WILL DISSIPATE HEADING INTO THIS EVENING. KCOS...LIGHT RAIN IS MOVING ACROSS EL PASO COUNTY NEAR THE TERMINAL. EXPECT PERIODS OF LIGHT RAIN THROUGH 14Z WITH REDUCED VIS AND CIGS TO MVFR. IT APPEARS TEMPERATURES WILL REMAIN WARM ENOUGH FOR ALL RAIN AT THE TERMINAL. ALL SHOWER ACTIVITY SHOULD BE DONE BY 17Z. STRONG WINDS OUT OF THE NORTHWEST WILL MOVE INTO THE REGION THIS MORNING WITH GUSTS IN EXCESS OF 40 KTS LIKELY. WINDS WILL DISSIPATE AFTER SUNSET. KPUB...THUNDERSTORMS WILL CONTINUE TO IMPACT THE TERMINAL THROUGH 14Z AND WITH SHOWERS IN THE VICINITY THROUGH 16Z. CIGS AND VIS WILL DROP TO MVFR TO IFR WITH THIS THUNDERSTORM ACTIVITY. STRONG WESTERLY WINDS GUSTS TO NEAR 40 KTS ARE EXPECTED THROUGH THIS EVENING. WINDS SHOULD DISSIPATE AFTER SUNSET. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ095>099. WINTER STORM WARNING UNTIL NOON MDT TODAY FOR COZ058-060-061-066- 068. && $$ UPDATE...PETERSEN SHORT TERM...MOZLEY LONG TERM...KT AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
515 AM MDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM MDT SUN APR 27 2014 CURRENTLY...STRONG UPPER LEVEL LOW PRESSURE CENTER IS CURRENTLY SITTING OVER SOUTHEAST COLORADO. RADAR IS STARTING TO LIGHT UP ALONG THE PALMER DIVIDE...SOUTH ALONG THE I-25 CORRIDOR TO PUEBLO. A FEW LIGHTNING STRIKES ARE ALSO BEING SEEN WITH THIS ACTIVITY. TEMPERATURES ARE COOL...WITH GENERALLY 30S TO 40S UNDER THE DEVELOPING PRECIPITATION. OUT EAST AHEAD OF THE PRECIPITATION ITS CURRENTLY IN THE 50S. GUSTY NORTH WINDS HAVE FILTERED INTO THE PALMER DIVIDE REGION AND SHOULD ONLY STRENGTHEN AND SPREAD ACROSS THE PLAINS THROUGH THE EARLY MORNING HOURS. IT IS ALSO CURRENTLY SNOWING ACROSS THE HIGHER ELEVATIONS...WITH AREA WEBCAMS INDICATING SNOW LEVELS STILL ABOVE 9 TO 10 KFT. TODAY...MODELS ALL IN DECENT AGREEMENT WITH THE UPPER LEVEL LOW SHIFTING NORTHEAST INTO SOUTH CENTRAL NEBRASKA BY THIS AFTERNOON. FOLLOWED A BLEND OF THE RAP AND HRRR HIGH RES MODEL SOLUTIONS AS FAR AS EVOLUTION OF THE STORM SYSTEM. ALL SOLUTIONS ARE DEVELOPING A TROWAL...WHICH IS IN ITS FORMATION STAGE EARLY THIS MORNING...AND TRACKING IT EAST ACROSS THE PLAINS THROUGH THE AFTERNOON AND EXITING KIOWA COUNTY BY SUNSET. UNDER THE TROWAL PRECIPITATION BAND...EXPECT TO SEE PERIODS OF LIGHT TO MODERATE RAINFALL ALONG WITH A FEW THUNDERSTORMS. THE MAIN THREAT FROM THUNDERSTORMS WILL BE LIGHTNING. MOST AREAS ACROSS THE PLAINS...ESPECIALLY AREAS NORTH OF HIGHWAY 50...WILL SEE WETTING RAINS...WITH AROUND ONE TO TWO TENTHS OF AN INCH OF PRECIPITATION. SNOW LEVELS REMAIN TRICKY. THE STORM SYSTEM IS QUITE WARM AND SUGGESTS SNOW LEVELS REMAINING AROUND 9 KFT. HOWEVER...THE CONVECTIVE NATURE OF THE SHOWER ACTIVITY WILL LIKELY FORCE SNOW LEVELS DOWN...ESPECIALLY OVER TELLER COUNTY AND THE PALMER DIVIDE...TO NEAR 8 TO 7 KFT. GIVEN THE WARM GROUND SURFACE TEMPERATURES...WE WILL LIKELY NOT SEE MUCH IN THE WAY OF ACCUMULATIONS OVER THE PALMER DIVIDE. UP IN THE MOUNTAINS ABOVE 9 KFT THERE WILL LIKELY BE A SOLID 6 TO 10 INCHES OF SNOW ALONG THE CONTINENTAL DIVIDE...WHILE AREAS OF THE EASTERN MOUNTAINS SEE AROUND 3 TO 6 INCHES. THE OTHER MAIN FORECAST ISSUE FOR THIS AFTERNOON WILL BE THE WINDS. A STRONG PRESSURE GRADIENT AROUND THE UPPER LEVEL STORM SYSTEM WILL HELP TO GENERATE STRONG NORTH TO NORTHWEST WINDS ACROSS EASTERN COLORADO FOR THIS AFTERNOON. MODEL GUIDANCE SUGGESTS SUSTAINED WINDS APPROACHING 30 KTS WITH GUSTS IN EXCESS OF 50 KTS POSSIBLE. THIS WILL LEAD TO DANGEROUS DRIVING CONDITIONS DUE TO STRONG CROSS WINDS ON EAST-WEST HIGHWAYS. ANY LOOSE OUTDOOR ITEMS SUCH AS PLANTS AND LAWN FURNITURE SHOULD BE BROUGHT INDOORS. TONIGHT...THE UPPER LEVEL STORM SYSTEM WILL CONTINUE TO DRIFT NORTH ACROSS CENTRAL NEBRASKA. THIS WILL KEEP THE REGION UNDER STRONG NORTHERLY FLOW. MODELS ALL IN GOOD AGREEMENT WITH PRECIPITATION COMING TO AN END ACROSS THE PLAINS AROUND 00Z/MON AND FOLLOWED THIS TREND IN THE FORECAST. LIGHT SNOW SHOWERS WILL LIKELY CONTINUE ALONG THE CONTINENTAL DIVIDE TONIGHT WITH THE CENTRAL MOUNTAINS FAVORED DUE TO NORTHWESTERLY OROGRAPHIC UPSLOPE FLOW. TEMPERATURES WILL BE COOL TONIGHT WITH LOWER TO MID 30S EXPECTED FOR THE LOWER ELEVATIONS. GIVEN THE NEAR FREEZING TEMPERATURES...THOSE WITH SENSITIVE OUTDOOR PLANTS SHOULD TAKE PRECAUTIONS TO PROTECT THEM. MOZLEY .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM MDT SUN APR 27 2014 ...CONTINUED COOL AND UNSETTLED... MODELS IN FAIRLY GOOD AGREEMENT WITH THE TRACK OF THE UPPER LOW THROUGH -----...AS IT MAKES SLOW PROGRESS ACROSS THE CENTRAL PLAINS BEFORE GRADUALLY LIFTING TO THE NORTHEAST INTO IA AND MN BY TUESDAY AFTERNOON. TRAILING ENERGY DROPPING DOWN THE WESTERN SIDE OF THE UPPER LOW WILL KEEP UNSETTLED WEATHER OVER THE REGION...ESPECIALLY ALONG THE CONTINENTAL DIVIDE WHERE PERIODIC LIGHT SNOW WILL CONTINUE...AND ACROSS NORTHERN AND EASTERN PORTIONS OF THE SOUTHEAST PLAINS AS ANOTHER LOBE OF ENERGY ROTATES GLANCES BY THE SOUTHEAST PLAINS ALONG THE WESTERN PERIPHERY OF THE UPPER LOW. OVERALL...ACCUMULATIONS REMAIN LIGHT AT THIS POINT. COULD BE FLIRTING WITH CRITICAL FIRE WEATHER CONDITIONS ON MONDAY ACROSS THE SOUTHEAST PLAINS WHERE WINDS WILL REMAIN QUITE STRONG...THOUGH WITH THE COOLER TEMPERATURES...DEW POINTS MAY NOT BE QUITE LOW ENOUGH TO HIT THE 3 HOUR WINDOW OF 15 PERCENT...SO NO FIRE WEATHER HIGHLIGHTS LOOK NECESSARY AT THIS POINT. TEMPERATURES WILL REMAIN BELOW NORMAL AND OVERNIGHT LOWS MONDAY NIGHT AND AGAIN TUESDAY NIGHT WILL STILL COME CLOSE OR HIT THE FREEZING MARK ACROSS THE SOUTHEAST PLAINS. TOO EARLY IN THE GROWING SEASON FOR FROST/FREEZE HIGHLIGHTS AS THESE DO NOT START UNTIL MAY 1ST. A REINFORCING SURGE OF COLD AIR DROPS THROUGH THE SOUTHEAST PLAINS TUESDAY NIGHT. WINDS AND CLOUDS BEHIND THIS MAY HELP KEEP TEMPERATURES SLIGHTLY ABOVE FREEZING ACROSS PORTIONS OF THE PLAINS. HOWEVER...MODELS DIFFER WITH QPF TUESDAY NIGHT...WITH GFS THE WETTEST MODEL...PRINTING 2-4 INCHES OF SNOW FOR THE SOUTHEAST MOUNTAINS. ECMWF ALSO SHOWS SOME SNOW FOR THE SE MTS/ADJACENT PLAINS...BUT IS MUCH LIGHTER...WHILE NAM IS VIRTUALLY DRY. FORECAST LEANS MORE TOWARDS THE ECMWF FOR NOW AS IT IS A NICE COMPROMISE. ANOTHER SHORTWAVE DROPS DOWN THE WESTERN SIDE OF THE BROAD UPPER LOW ACROSS CO ON WEDNESDAY. GFS AND ECMWF PULL THE H7 WINDS A LITTLE MORE OUT OF THE NORTHEAST PERHAPS GIVING THE SE MTS ANOTHER SHOT OF SOME SNOW. GFS IS MUCH HEAVIER THAN EC WITH QPF...SO UNCERTAINTY REMAINS HIGH. UPPER LOW PULLS AWAY TO THE NORTHWEST BY LATE IN THE WEEK...WITH FLOW ALOFT GRADUALLY BECOMING MORE WESTERLY WITH TIME. THIS WILL BODE FOR A GRADUAL WARM UP...THOUGH ECMWF BRINGS ANOTHER FRONT THROUGH THE SOUTHEAST PLAINS FRI NIGHT...WHICH GFS KEEPS WELL TO THE NORTH AND EAST. TOO SOON TO SAY WITH CONFIDENCE...SO HAVE TAPERED BACK THE WARM UP A FEW DEGREES. -KT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 349 AM MDT SUN APR 27 2014 KALS...A FEW SNOW SHOWERS HAVE MOVED ACROSS THE SAN LUIS VALLEY THIS MORNING. MOST OF THE ACTIVITY SHOULD BE DIMINISHING THROUGH 16Z WITH LIMITED IMPACTS TO THE TERMINAL. STRONG WINDS ARE FORECAST TO DEVELOP FOR THIS AFTERNOON WITH WESTERLY GUSTS TO NEAR 35 KTS LIKELY. WINDS WILL DISSIPATE HEADING INTO THIS EVENING. KCOS...LIGHT RAIN IS MOVING ACROSS EL PASO COUNTY NEAR THE TERMINAL. EXPECT PERIODS OF LIGHT RAIN THROUGH 14Z WITH REDUCED VIS AND CIGS TO MVFR. IT APPEARS TEMPERATURES WILL REMAIN WARM ENOUGH FOR ALL RAIN AT THE TERMINAL. ALL SHOWER ACTIVITY SHOULD BE DONE BY 17Z. STRONG WINDS OUT OF THE NORTHWEST WILL MOVE INTO THE REGION THIS MORNING WITH GUSTS IN EXCESS OF 40 KTS LIKELY. WINDS WILL DISSIPATE AFTER SUNSET. KPUB...THUNDERSTORMS WILL CONTINUE TO IMPACT THE TERMINAL THROUGH 14Z AND WITH SHOWERS IN THE VICINITY THROUGH 16Z. CIGS AND VIS WILL DROP TO MVFR TO IFR WITH THIS THUNDERSTORM ACTIVITY. STRONG WESTERLY WINDS GUSTS TO NEAR 40 KTS ARE EXPECTED THROUGH THIS EVENING. WINDS SHOULD DISSIPATE AFTER SUNSET. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL NOON MDT TODAY FOR COZ058-060-061-066- 068. && $$ SHORT TERM...MOZLEY LONG TERM...KT AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
955 PM EDT Mon Apr 28 2014 ...SEVERE STORMS AND FLOODING POSSIBLE ACROSS PORTIONS OF THE AREA TUESDAY AND WEDNESDAY... .Near Term [Through Tonight]... A large upper level trough is currently located over the central US, with a ridge axis to its east stretching from the eastern Great Lakes southward into the Carolinas. Under the trough, a 988 mb surface low is centered over eastern Nebraska, with a warm front stretching eastward into the Ohio Valley region and a cold front stretching southward along the Mississippi River. In the warm sector between these fronts, severe thunderstorms have developed this evening, with numerous supercells and associated tornadoes in MS and northwestern AL. These cells have started to congeal into a multi-cellular system, and will likely develop into more of a squall line overnight as they approach the NW edge of our CWA. High-resolution models such the HRRR show this feature entering our far NW counties between 09-12Z Tuesday. As a result, heavy rain, potentially severe winds, isolated tornadoes, and frequent lightning could impact this area near dawn. Otherwise, precipitation should not occur in the rest of our CWA before 12Z tomorrow morning. Warm and humid conditions will prevail overnight across the region, with lows ranging from the lower 70s in the west to the upper 60s in eastern counties. && .Aviation... [Through 00Z Wednesday] VFR conditions will begin to deteriorate this evening bringing low cigs and visbys to the area. Areas of fog are likely throughout the CWA beginning as early as 03 UTC in ECP. Thunderstorms will arrive from the NW at DHN and ECP around dawn, some of which could be severe. There storms will spread over the area throughout the day keeping ceilings low and southerly winds gusty. && .Prev Discussion [255 PM EDT]... .Short Term [Tuesday Through Wednesday Night]... An unsettled pattern will continue through the short term period. The large mid-upper level low will slowly translate from near Iowa northeastward to the Great Lakes area by Wednesday night. The associated surface cold front will approach and eventually push into our CWA. This slow pattern will keep a severe weather threat through the period. SPC has our CWA highlighted for a slight risk of severe weather each day and our locally run CAM models show about a 50 percent probability for severe TSTMS over our western zones Tuesday. The main threat would be damaging winds based on the convective mode, but hail and tornadoes would also be possible based on the steep lapse rates and low-level shear profiles respectively. Additionally, there is a concern for flash flooding at least for our western zones and the flash flood watch in place will remain unchanged for now. PoPs will be justifiably above climo with a west to east taper for most periods. .Long Term [Thursday Through Monday]... The latest GFS and ECMWF solutions continue in to be in fairly good agreement WRT the upper level pattern. The stacked low pressure system will be over the Great Lakes Region with a broad deep trough roughly from the continental divide to the east coast to start the period. A potent shortwave will further sharpen the trough as it drops from the central plains into the southeast Thursday night into Friday. As the shortwave moves east the mid/upper level flow becomes zonal by the end of the weekend. Weak ridging returns to the area to begin the next week. At the surface, a weak front will cut through our CWA Thursday and push to our east by Friday. A wave is forecast to develop on the boundary over the northeast Gulf on Friday. This along with the approaching shortwave and increasing deep layer moisture will keep rain chances in the forecast Friday. High pressure builds in with dry weather for the local region over the weekend and early next week. Temps will be below seasonal levels Friday in the wake of the front with max temps in the upper 60s to lower 70s. Otherwise, temps will be at or just above climo through the period. .Marine... Southerly winds of 15 to 20 knots will continue across the coastal waters at least through Tuesday. Tuesday night and into Wednesday winds and seas are now expected to elevate to advisory levels. Winds will veer from west to east as a cold front passes through later on Wednesday into Wednesday night with diminishing winds and seas. .Fire Weather... Moisture levels will remain high through the upcoming week, so no fire weather concerns are expected. .Hydrology... Locally heavy rainfall is expected this week beginning late tonight and ending sometime on Friday. Rainfall totals for the week will range from 4-6 inches in the Western Florida Panhandle and Southeast Alabama, with higher amounts possible. Elsewhere 2-4 inches of rain is expected across the remainder of the CWA. Most area rivers have crested and have begun falling. However, but if these forecast rainfall totals occur, we expect many area rivers to be back in minor flood stage by the end of the week. The most up-to-date river forecast information can always be found on our AHPS page (below). http:/water.weather.gov/ahps2/index.php?wfo=tae. && .Preliminary Point Temps/PoPs... Tallahassee 69 85 70 86 63 / 10 40 40 50 40 Panama City 71 81 71 80 64 / 20 70 60 60 40 Dothan 70 85 71 83 58 / 50 80 60 70 40 Albany 69 86 71 84 60 / 10 70 50 60 50 Valdosta 67 88 70 86 64 / 10 30 30 50 40 Cross City 67 86 69 86 66 / 10 20 30 30 30 Apalachicola 70 80 73 80 65 / 10 50 40 60 40 && .TAE Watches/Warnings/Advisories... FL...Flash Flood Watch from 4 AM EDT /3 AM CDT/ Tuesday through Wednesday afternoon for Calhoun-Central Walton-Coastal Bay- Coastal Gulf-Gadsden-Holmes-Inland Bay-Inland Gulf-Inland Walton-Jackson-Liberty-South Walton-Washington. High Rip Current Risk until 4 AM EDT /3 AM CDT/ Tuesday for Coastal Bay-Coastal Franklin-Coastal Gulf-South Walton. GA...Flash Flood Watch from 4 AM EDT Tuesday through Wednesday afternoon for Baker-Calhoun-Clay-Decatur-Early-Miller- Quitman-Randolph-Seminole-Terrell. AL...Flash Flood Watch from 3 AM CDT Tuesday through Wednesday afternoon for Coffee-Dale-Geneva-Henry-Houston. GM...None. && $$ NEAR TERM...DVD/LAHR SHORT TERM...BARRY LONG TERM...BARRY AVIATION...BLOCK/HELLER MARINE...BARRY FIRE WEATHER...BLOCK HYDROLOGY...BOLDEN
AREA FORECAST DISCUSSION
NWS MIAMI FL
143 PM EDT SUN APR 27 2014 .AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST WITH SEA BREEZES ALONG BOTH COASTS IN THE AFTERNOONS. THERE COULD BE A FEW TSRA OVER THE INTERIOR AS THE BOUNDARIES CONVERGE BUT THESE WILL REMAIN WELL INLAND FROM THE TERMINALS. KOB && .PREV DISCUSSION... /ISSUED 1130 AM EDT SUN APR 27 2014/ UPDATE... THE SHORT TERM FORECAST WAS UPDATED TO REFLECT A CHANCE OF CONVECTION THIS AFTERNOON...MAINLY EXPECTED IN THE INTERIOR REGION AND FORECAST TO BE A LATE START AROUND 20-21Z WITH SCATTERED SHOWERS AND THUNDERSTORMS ADDED TO THE FORECAST FOR THE INTERIOR. THE CHANGES WERE MADE DUE TO INSPECTION OF THE 12Z SOUNDING AND RECENT MESO-SCALE MODEL GUIDANCE. 60 PREV DISCUSSION... /ISSUED 728 AM EDT SUN APR 27 2014/ AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST WITH SURFACE WIND L/V EARLY ALLOWING FOR SEA BREEZES TO DEVELOP ALONG BOTH COASTS. THERE COULD BE A FEW SHOWERS DEVELOP AS THE BOUNDARIES MERGE BUT ANY ACTIVITY WILL BE WELL INLAND FROM THE TERMINALS. KOB PREV DISCUSSION... /ISSUED 400 AM EDT SUN APR 27 2014/ DISCUSSION... WATER VAPOR IMAGERY AND RAP ANALYSIS THIS MORNING SHOWED A DRY AIRMASS ACROSS SOUTH FLORIDA WITH AN UPPER RIDGE CENTERED OVER THE EASTERN GULF NORTHWARD INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES. A CUTOFF UPPER LEVEL LOW WAS LOCATED OVER THE INTERMOUNTAIN WEST...AND AN UPPER TROUGH WAS OVER THE NORTHEAST. THE DRIER AIR IN THE LOW/MID LEVELS IS FORECAST TO REMAIN ACROSS AT LEAST THE SOUTHERN HALF OF THE REGION INTO TUESDAY MORNING. SO ANY RAIN CHANCES TODAY AND MONDAY WILL BE CONFINED TO THE LAKE REGION. AT THE SURFACE...A WEAK RIDGE OF HIGH PRESSURE WAS CENTERED TO THE EAST OF FLORIDA. THIS RIDGE WILL SLIDE EAST OVER THE NEXT COUPLE DAYS...WITH LIGHT TO MODERATE SOUTHEAST FLOW ACROSS SOUTH FLORIDA. TODAY AND TONIGHT...A SMALL INCREASE IN MOISTURE IS FORECAST ACROSS NORTHERN AND CENTRAL FLORIDA AS A WEAK SHORTWAVE MOVES EASTWARD THIS AFTERNOON. MAINLY DRY AND WARM CONDITIONS WILL CONTINUE FOR SOUTH FLORIDA AS THE UPPER RIDGE SLIDES OVER THE REGION. HOWEVER...LAKE BREEZE AND SEA BREEZE INTERACTION MAY BE ENOUGH TO GET A SHOWER OR TWO TO DEVELOP OVER GLADES COUNTY LATE THIS AFTERNOON. LOW LEVEL MOISTURE WILL INCREASE SLIGHTLY TONIGHT WITH THE STRENGTHENING SOUTHEAST WINDS...AND DEWPOINTS WILL CREEP UP TOWARDS 70F. OVERNIGHT LOWS WILL BE WARM...WITH TEMPERATURES IN THE MID/UPPER 60S INTERIOR TO LOW TO MID 70S FOR THE EAST COAST METRO AREAS. MONDAY AND TUESDAY...THE LARGE AND ANOMALOUS UPPER LEVEL LOW IS FORECAST TO BE LOCATED ACROSS THE MIDDLE OF THE NATION...WITH THE UPPER LEVEL RIDGE OVER SOUTH FLORIDA AND UP THE EASTERN SEA BOARD. THE BAND OF LOW/MID LEVEL DRY AIR WILL REMAIN OVER THE SOUTHERN HALF OF THE REGION...AND ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS IS POSSIBLE ACROSS THE LAKE REGION ON MONDAY. THE BAND OF DRIER AIR IS FORECAST TO PUSH INTO THE WESTERN ATLANTIC BY TUESDAY EVENING...AND SLIGHT CHANCES OF SHOWERS AND STORMS RETURN TO MOST OF THE INTERIOR. TEMPERATURES WILL BE WARM WITH HIGHS IN THE MID 80S TO LOWER 90S. LOWS ARE FORECAST TO BE IN THE MID/UPPER 60S INTERIOR TO LOW/MID 70S EAST COAST METRO AREAS. WEDNESDAY AND THURSDAY...LARGE UPPER LOW/TROUGH WILL REMAIN UPPER MIDWEST/GREAT LAKES REGION...WITH UPPER RIDGING HOLDING ON ACROSS SOUTH FLORIDA. A FRONTAL BOUNDARY IS FORECAST TO PUSH INTO NORTHERN FLORIDA AND STALL. MOISTURE IS FORECAST TO INCREASE AND ISOLATED/SCATTERED SHOWERS AND STORMS ARE FORECAST MAINLY ACROSS THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. THE BEST CHANCES OF RAIN WILL REMAIN FROM THE LAKE REGION NORTHWARD CLOSER TO THE FRONTAL BOUNDARY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND SIMILAR TO THE EARLIER IN THE WEEK. FRIDAY AND SATURDAY...MODELS BEGIN TO DIVERGE SLIGHTLY THE END OF THE WEEK INTO NEXT WEEKEND...DUE TO THEIR HANDLING OF SOUTHERN STREAM ENERGY MOVING OUT OF THE INTERMOUNTAIN WEST. THE ECMWF IS SLIGHTLY DEEPER WITH THE UPPER TROUGH AS IT PHASES THE SHORTWAVE ENERGY WITH THE TROUGH...AND DEVELOPS AN AREA OF LOW PRESSURE ALONG THE FRONTAL BOUNDARY OVER THE GULF OF MEXICO ON FRIDAY. THIS RESULTS IN THE FRONT PUSHING BACK NORTHWARD INTO THE PANHANDLE ON FRIDAY...BEFORE FINALLY PUSHING TOWARDS THE REGION THE LATTER PART OF NEXT WEEKEND. THE GFS HAS THE FRONT NEAR THE REGION ON FRIDAY AND OVER THE REGION ON SATURDAY...WITH HIGHER RAIN CHANCES. FOR NOW...KEPT LOW END CHANCES OF SHOWERS AND STORMS FOR FRIDAY AND SATURDAY. AVIATION... VFR CONDITIONS DOMINATE THROUGH MONDAY. SLIGHTLY STRONGER SOUTHEAST FLOW THIS AFTERNOON SHOULD MEAN LITTLE SEA-BREEZE IMPACT FOR EASTERN TERMINALS...WITH GULF-BREEZE INTRUSION EXPECTED IN NAPLES AFTER 18Z...SHIFTING WINDS TO W. MARINE... A WEAK PRESSURE GRADIENT CONTINUES ACROSS THE REGIONAL WATERS WITH MORE SOUTHEASTERLY FLOW RETURNING TODAY INTO EARLY NEXT WEEK. IN GENERAL SEAS ARE EXPECTED TO BE 3 FEET OR LESS TODAY WITH JUST A GRADUAL INCREASE IN WINDS AND SEAS EARLY NEXT WEEK. && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1130 AM EDT SUN APR 27 2014 .UPDATE... THE SHORT TERM FORECAST WAS UPDATED TO REFLECT A CHANCE OF CONVECTION THIS AFTERNOON...MAINLY EXPECTED IN THE INTERIOR REGION AND FORECAST TO BE A LATE START AROUND 20-21Z WITH SCATTERED SHOWERS AND THUNDERSTORMS ADDED TO THE FORECAST FOR THE INTERIOR. THE CHANGES WERE MADE DUE TO INSPECTION OF THE 12Z SOUNDING AND RECENT MESO-SCALE MODEL GUIDANCE. 60 && .PREV DISCUSSION... /ISSUED 728 AM EDT SUN APR 27 2014/ AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST WITH SURFACE WIND L/V EARLY ALLOWING FOR SEA BREEZES TO DEVELOP ALONG BOTH COASTS. THERE COULD BE A FEW SHOWERS DEVELOP AS THE BOUNDARIES MERGE BUT ANY ACTIVITY WILL BE WELL INLAND FROM THE TERMINALS. KOB PREV DISCUSSION... /ISSUED 400 AM EDT SUN APR 27 2014/ DISCUSSION... WATER VAPOR IMAGERY AND RAP ANALYSIS THIS MORNING SHOWED A DRY AIRMASS ACROSS SOUTH FLORIDA WITH AN UPPER RIDGE CENTERED OVER THE EASTERN GULF NORTHWARD INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES. A CUTOFF UPPER LEVEL LOW WAS LOCATED OVER THE INTERMOUNTAIN WEST...AND AN UPPER TROUGH WAS OVER THE NORTHEAST. THE DRIER AIR IN THE LOW/MID LEVELS IS FORECAST TO REMAIN ACROSS AT LEAST THE SOUTHERN HALF OF THE REGION INTO TUESDAY MORNING. SO ANY RAIN CHANCES TODAY AND MONDAY WILL BE CONFINED TO THE LAKE REGION. AT THE SURFACE...A WEAK RIDGE OF HIGH PRESSURE WAS CENTERED TO THE EAST OF FLORIDA. THIS RIDGE WILL SLIDE EAST OVER THE NEXT COUPLE DAYS...WITH LIGHT TO MODERATE SOUTHEAST FLOW ACROSS SOUTH FLORIDA. TODAY AND TONIGHT...A SMALL INCREASE IN MOISTURE IS FORECAST ACROSS NORTHERN AND CENTRAL FLORIDA AS A WEAK SHORTWAVE MOVES EASTWARD THIS AFTERNOON. MAINLY DRY AND WARM CONDITIONS WILL CONTINUE FOR SOUTH FLORIDA AS THE UPPER RIDGE SLIDES OVER THE REGION. HOWEVER...LAKE BREEZE AND SEA BREEZE INTERACTION MAY BE ENOUGH TO GET A SHOWER OR TWO TO DEVELOP OVER GLADES COUNTY LATE THIS AFTERNOON. LOW LEVEL MOISTURE WILL INCREASE SLIGHTLY TONIGHT WITH THE STRENGTHENING SOUTHEAST WINDS...AND DEWPOINTS WILL CREEP UP TOWARDS 70F. OVERNIGHT LOWS WILL BE WARM...WITH TEMPERATURES IN THE MID/UPPER 60S INTERIOR TO LOW TO MID 70S FOR THE EAST COAST METRO AREAS. MONDAY AND TUESDAY...THE LARGE AND ANOMALOUS UPPER LEVEL LOW IS FORECAST TO BE LOCATED ACROSS THE MIDDLE OF THE NATION...WITH THE UPPER LEVEL RIDGE OVER SOUTH FLORIDA AND UP THE EASTERN SEA BOARD. THE BAND OF LOW/MID LEVEL DRY AIR WILL REMAIN OVER THE SOUTHERN HALF OF THE REGION...AND ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS IS POSSIBLE ACROSS THE LAKE REGION ON MONDAY. THE BAND OF DRIER AIR IS FORECAST TO PUSH INTO THE WESTERN ATLANTIC BY TUESDAY EVENING...AND SLIGHT CHANCES OF SHOWERS AND STORMS RETURN TO MOST OF THE INTERIOR. TEMPERATURES WILL BE WARM WITH HIGHS IN THE MID 80S TO LOWER 90S. LOWS ARE FORECAST TO BE IN THE MID/UPPER 60S INTERIOR TO LOW/MID 70S EAST COAST METRO AREAS. WEDNESDAY AND THURSDAY...LARGE UPPER LOW/TROUGH WILL REMAIN UPPER MIDWEST/GREAT LAKES REGION...WITH UPPER RIDGING HOLDING ON ACROSS SOUTH FLORIDA. A FRONTAL BOUNDARY IS FORECAST TO PUSH INTO NORTHERN FLORIDA AND STALL. MOISTURE IS FORECAST TO INCREASE AND ISOLATED/SCATTERED SHOWERS AND STORMS ARE FORECAST MAINLY ACROSS THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. THE BEST CHANCES OF RAIN WILL REMAIN FROM THE LAKE REGION NORTHWARD CLOSER TO THE FRONTAL BOUNDARY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND SIMILAR TO THE EARLIER IN THE WEEK. FRIDAY AND SATURDAY...MODELS BEGIN TO DIVERGE SLIGHTLY THE END OF THE WEEK INTO NEXT WEEKEND...DUE TO THEIR HANDLING OF SOUTHERN STREAM ENERGY MOVING OUT OF THE INTERMOUNTAIN WEST. THE ECMWF IS SLIGHTLY DEEPER WITH THE UPPER TROUGH AS IT PHASES THE SHORTWAVE ENERGY WITH THE TROUGH...AND DEVELOPS AN AREA OF LOW PRESSURE ALONG THE FRONTAL BOUNDARY OVER THE GULF OF MEXICO ON FRIDAY. THIS RESULTS IN THE FRONT PUSHING BACK NORTHWARD INTO THE PANHANDLE ON FRIDAY...BEFORE FINALLY PUSHING TOWARDS THE REGION THE LATTER PART OF NEXT WEEKEND. THE GFS HAS THE FRONT NEAR THE REGION ON FRIDAY AND OVER THE REGION ON SATURDAY...WITH HIGHER RAIN CHANCES. FOR NOW...KEPT LOW END CHANCES OF SHOWERS AND STORMS FOR FRIDAY AND SATURDAY. AVIATION... VFR CONDITIONS DOMINATE THROUGH MONDAY. SLIGHTLY STRONGER SOUTHEAST FLOW THIS AFTERNOON SHOULD MEAN LITTLE SEA-BREEZE IMPACT FOR EASTERN TERMINALS...WITH GULF-BREEZE INTRUSION EXPECTED IN NAPLES AFTER 18Z...SHIFTING WINDS TO W. MARINE... A WEAK PRESSURE GRADIENT CONTINUES ACROSS THE REGIONAL WATERS WITH MORE SOUTHEASTERLY FLOW RETURNING TODAY INTO EARLY NEXT WEEK. IN GENERAL SEAS ARE EXPECTED TO BE 3 FEET OR LESS TODAY WITH JUST A GRADUAL INCREASE IN WINDS AND SEAS EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 88 73 85 75 / 0 10 10 0 FORT LAUDERDALE 87 77 86 78 / 0 0 0 10 MIAMI 89 76 87 76 / 0 0 10 10 NAPLES 89 70 89 71 / 10 10 10 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
728 AM EDT SUN APR 27 2014 .AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST WITH SURFACE WIND L/V EARLY ALLOWING FOR SEA BREEZES TO DEVELOP ALONG BOTH COASTS. THERE COULD BE A FEW SHOWERS DEVELOP AS THE BOUNDARIES MERGE BUT ANY ACTIVITY WILL BE WELL INLAND FROM THE TERMINALS. KOB && .PREV DISCUSSION... /ISSUED 400 AM EDT SUN APR 27 2014/ DISCUSSION... WATER VAPOR IMAGERY AND RAP ANALYSIS THIS MORNING SHOWED A DRY AIRMASS ACROSS SOUTH FLORIDA WITH AN UPPER RIDGE CENTERED OVER THE EASTERN GULF NORTHWARD INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES. A CUTOFF UPPER LEVEL LOW WAS LOCATED OVER THE INTERMOUNTAIN WEST...AND AN UPPER TROUGH WAS OVER THE NORTHEAST. THE DRIER AIR IN THE LOW/MID LEVELS IS FORECAST TO REMAIN ACROSS AT LEAST THE SOUTHERN HALF OF THE REGION INTO TUESDAY MORNING. SO ANY RAIN CHANCES TODAY AND MONDAY WILL BE CONFINED TO THE LAKE REGION. AT THE SURFACE...A WEAK RIDGE OF HIGH PRESSURE WAS CENTERED TO THE EAST OF FLORIDA. THIS RIDGE WILL SLIDE EAST OVER THE NEXT COUPLE DAYS...WITH LIGHT TO MODERATE SOUTHEAST FLOW ACROSS SOUTH FLORIDA. TODAY AND TONIGHT...A SMALL INCREASE IN MOISTURE IS FORECAST ACROSS NORTHERN AND CENTRAL FLORIDA AS A WEAK SHORTWAVE MOVES EASTWARD THIS AFTERNOON. MAINLY DRY AND WARM CONDITIONS WILL CONTINUE FOR SOUTH FLORIDA AS THE UPPER RIDGE SLIDES OVER THE REGION. HOWEVER...LAKE BREEZE AND SEA BREEZE INTERACTION MAY BE ENOUGH TO GET A SHOWER OR TWO TO DEVELOP OVER GLADES COUNTY LATE THIS AFTERNOON. LOW LEVEL MOISTURE WILL INCREASE SLIGHTLY TONIGHT WITH THE STRENGTHENING SOUTHEAST WINDS...AND DEWPOINTS WILL CREEP UP TOWARDS 70F. OVERNIGHT LOWS WILL BE WARM...WITH TEMPERATURES IN THE MID/UPPER 60S INTERIOR TO LOW TO MID 70S FOR THE EAST COAST METRO AREAS. MONDAY AND TUESDAY...THE LARGE AND ANOMALOUS UPPER LEVEL LOW IS FORECAST TO BE LOCATED ACROSS THE MIDDLE OF THE NATION...WITH THE UPPER LEVEL RIDGE OVER SOUTH FLORIDA AND UP THE EASTERN SEA BOARD. THE BAND OF LOW/MID LEVEL DRY AIR WILL REMAIN OVER THE SOUTHERN HALF OF THE REGION...AND ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS IS POSSIBLE ACROSS THE LAKE REGION ON MONDAY. THE BAND OF DRIER AIR IS FORECAST TO PUSH INTO THE WESTERN ATLANTIC BY TUESDAY EVENING...AND SLIGHT CHANCES OF SHOWERS AND STORMS RETURN TO MOST OF THE INTERIOR. TEMPERATURES WILL BE WARM WITH HIGHS IN THE MID 80S TO LOWER 90S. LOWS ARE FORECAST TO BE IN THE MID/UPPER 60S INTERIOR TO LOW/MID 70S EAST COAST METRO AREAS. WEDNESDAY AND THURSDAY...LARGE UPPER LOW/TROUGH WILL REMAIN UPPER MIDWEST/GREAT LAKES REGION...WITH UPPER RIDGING HOLDING ON ACROSS SOUTH FLORIDA. A FRONTAL BOUNDARY IS FORECAST TO PUSH INTO NORTHERN FLORIDA AND STALL. MOISTURE IS FORECAST TO INCREASE AND ISOLATED/SCATTERED SHOWERS AND STORMS ARE FORECAST MAINLY ACROSS THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. THE BEST CHANCES OF RAIN WILL REMAIN FROM THE LAKE REGION NORTHWARD CLOSER TO THE FRONTAL BOUNDARY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND SIMILAR TO THE EARLIER IN THE WEEK. FRIDAY AND SATURDAY...MODELS BEGIN TO DIVERGE SLIGHTLY THE END OF THE WEEK INTO NEXT WEEKEND...DUE TO THEIR HANDLING OF SOUTHERN STREAM ENERGY MOVING OUT OF THE INTERMOUNTAIN WEST. THE ECMWF IS SLIGHTLY DEEPER WITH THE UPPER TROUGH AS IT PHASES THE SHORTWAVE ENERGY WITH THE TROUGH...AND DEVELOPS AN AREA OF LOW PRESSURE ALONG THE FRONTAL BOUNDARY OVER THE GULF OF MEXICO ON FRIDAY. THIS RESULTS IN THE FRONT PUSHING BACK NORTHWARD INTO THE PANHANDLE ON FRIDAY...BEFORE FINALLY PUSHING TOWARDS THE REGION THE LATTER PART OF NEXT WEEKEND. THE GFS HAS THE FRONT NEAR THE REGION ON FRIDAY AND OVER THE REGION ON SATURDAY...WITH HIGHER RAIN CHANCES. FOR NOW...KEPT LOW END CHANCES OF SHOWERS AND STORMS FOR FRIDAY AND SATURDAY. AVIATION... VFR CONDITIONS DOMINATE THROUGH MONDAY. SLIGHTLY STRONGER SOUTHEAST FLOW THIS AFTERNOON SHOULD MEAN LITTLE SEA-BREEZE IMPACT FOR EASTERN TERMINALS...WITH GULF-BREEZE INTRUSION EXPECTED IN NAPLES AFTER 18Z...SHIFTING WINDS TO W. MARINE... A WEAK PRESSURE GRADIENT CONTINUES ACROSS THE REGIONAL WATERS WITH MORE SOUTHEASTERLY FLOW RETURNING TODAY INTO EARLY NEXT WEEK. IN GENERAL SEAS ARE EXPECTED TO BE 3 FEET OR LESS TODAY WITH JUST A GRADUAL INCREASE IN WINDS AND SEAS EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 88 73 85 75 / 0 10 10 0 FORT LAUDERDALE 87 77 86 78 / 0 0 0 10 MIAMI 89 76 87 76 / 0 0 10 10 NAPLES 89 70 89 71 / 10 10 10 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS JACKSONVILLE FL
625 AM EDT SUN APR 27 2014 .SHORT TERM...TODAY AND TONIGHT...LATEST HRRR AND NARRE MODELS SHOW LOW CLOUDS AND FOG FORMING ALONG FL GULF COAST AND FL ATLANTIC COAST EARLY THIS MORNING. FOG/CLOUDS SHOULD BURN OFF SHORTLY AFTER SUNRISE AGAIN. WEAK STATIONARY FRONT OVER THE AREA WILL DISSIPATE TODAY AS SHORT WAVE RIDGE AXIS APPROACHES FROM THE WEST. WEAK WINDS WILL ALLOW SEABREEZES TO MOVE INLAND REACHING THE INTERIOR BY LATE AFTERNOON AND EARLY EVENING. HAVE KEPT SLGT CHANCE TO CHANCE AFTN/EVEN POPS AS MOISTURE GRADUALLY INCREASES TODAY. A WEAK MID LEVEL IMPULSE WILL RIDE OVER THE RIDGE POSSIBLY ENHANCING SHRA/TSRA ESPECIALLY NEAR THE SEABREEZE COLLISION. TEMPERATURES WILL BE WARM AGAIN WITH MAX TEMPS APPROACHING 90 DEGREES WELL INLAND AND AROUND 80 COAST. MIN TEMPS TONIGHT WILL BE IN THE 60S. .MONDAY THROUGH TUESDAY...LOW AMPLITUDE RIDGING MONDAY WILL FLATTEN MONDAY NIGHT/TUESDAY AS A LARGE TROUGH MOVES ACROSS THE MISSISSIPPI VALLEY. DEEP MOISTURE WILL REMAIN WELL TO THE WEST...SO PRECIP WILL BE CONFINED TO THE AFTN/EARLY EVENING HOURS WITH MAINLY SEABREEZE AND SMALL SCALE INTERACTIONS AS THE TRIGGERS. WILL KEEP POPS SLIGHT CHANCE. HIGH TEMPERATURES WILL RANGE FROM THE UPPER 80S/AROUND 90 INLAND TO THE LOWER/MID 80S COAST. LOWS IN THE MID/UPPER 60S WILL GENERALLY PREVAIL. .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ECMWF/GFS COMING INTO A BIT BETTER AGREEMENT WITH THE TROUGH AND ASSOCIATED SURFACE COLD FRONT...BRINGING AN INITIAL SHORTWAVE ACROSS SE GA WEDNESDAY...SLOWLY BRINGING THE TROUGH INTO THE REGION LATE IN THE WEEK...WITH THE SYSTEMS COLD FRONT CROSSING THE REGION SATURDAY. STILL SOME TIMING DIFFERENCES...SO WILL KEEP POPS CHANCE FROM LATE WEDNESDAY INTO SATURDAY...WITH LOWERING POPS SATURDAY NW TO SE DURING THE DAY. WITH THE MID/UPPER LEVEL FORCING PROGGED TO BE STRETCHING OUT AS IT CROSSES THE REGION...DO NOT EXPECT ORGANIZED SEVERE STORMS LIKE THE SYSTEM IS CURRENTLY PRODUCING IN THE CENTRAL PLAINS. ABOVE NORMAL TEMPERATURES WEDNESDAY WILL GRADUALLY COOL TO NEAR NORMAL BY THE WEEKEND. && .AVIATION... AREAS OF MVFR/LOCAL IFR EARLY THIS MORNING WILL DISSIPATE BY 13-14Z. OTHERWISE...VFR WILL PREVAIL LATE THIS MORNING INTO THE OVERNIGHT HOURS. ISOLATED TO WIDELY SCATTERED SHOWERS WILL LIKELY DEVELOP ALONG THE SEABREEZE THIS AFTN...WILL USE VCSH FOR GNV/VQQ. ISOLATED MVFR CIGS CANNOT BE RULED OUT...BUT CONFIDENCE IS TOO SMALL TO INCLUDE IN THE TERMINALS FOR NOW. SOME MVFR BR WILL BE POSSIBLE FOR VQQ/GNV LATE IN THE OVERNIGHT TONIGHT. && .MARINE...SURFACE HIGH PRESSURE OFF THE EAST COAST WILL RESULT IN A S TO SE FLOW THE NEXT FEW DAYS ENHANCED BY AFTERNOON SEABREEZE FORMATION. THUNDERSTORM ACTIVITY WILL INCREASE MID TO LATE WEEK AS A SLOW MOVING COLD FRONT APPROACHES THE EAST COAST. WINDS WILL LIKELY INCREASE TO CAUTION LEVELS...AND POSSIBLY TO NEAR ADVISORY CONDITIONS OFFSHORE TUESDAY THROUGH WEDNESDAY NIGHT. RIP CURRENTS: LOW RISK TODAY AND MONDAY. && .HYDROLOGY...MAJOR FLOOD STAGE REACHED AT THREE RIVER ESTATES ON THE SUWANNEE RIVER...THIS WILL PERSIST THROUGH THE WEEK. MINOR TO MODERATE FLOODING WILL ALSO CONTINUE ON SEVERAL OTHER NE FL/SE GA RIVERS. && .PRELIMINARY POINT TEMPS/POPS... AMG 88 63 88 65 / 30 20 10 10 SSI 79 67 80 67 / 10 10 10 20 JAX 88 63 89 67 / 20 10 20 20 SGJ 81 67 84 67 / 10 10 20 20 GNV 89 66 88 65 / 30 20 20 20 OCF 89 65 89 65 / 30 20 20 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ ZIBURA/ALLEN
AREA FORECAST DISCUSSION
NWS MIAMI FL
400 AM EDT SUN APR 27 2014 .DISCUSSION... WATER VAPOR IMAGERY AND RAP ANALYSIS THIS MORNING SHOWED A DRY AIRMASS ACROSS SOUTH FLORIDA WITH AN UPPER RIDGE CENTERED OVER THE EASTERN GULF NORTHWARD INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES. A CUTOFF UPPER LEVEL LOW WAS LOCATED OVER THE INTERMOUNTAIN WEST...AND AN UPPER TROUGH WAS OVER THE NORTHEAST. THE DRIER AIR IN THE LOW/MID LEVELS IS FORECAST TO REMAIN ACROSS AT LEAST THE SOUTHERN HALF OF THE REGION INTO TUESDAY MORNING. SO ANY RAIN CHANCES TODAY AND MONDAY WILL BE CONFINED TO THE LAKE REGION. AT THE SURFACE...A WEAK RIDGE OF HIGH PRESSURE WAS CENTERED TO THE EAST OF FLORIDA. THIS RIDGE WILL SLIDE EAST OVER THE NEXT COUPLE DAYS...WITH LIGHT TO MODERATE SOUTHEAST FLOW ACROSS SOUTH FLORIDA. TODAY AND TONIGHT...A SMALL INCREASE IN MOISTURE IS FORECAST ACROSS NORTHERN AND CENTRAL FLORIDA AS A WEAK SHORTWAVE MOVES EASTWARD THIS AFTERNOON. MAINLY DRY AND WARM CONDITIONS WILL CONTINUE FOR SOUTH FLORIDA AS THE UPPER RIDGE SLIDES OVER THE REGION. HOWEVER...LAKE BREEZE AND SEA BREEZE INTERACTION MAY BE ENOUGH TO GET A SHOWER OR TWO TO DEVELOP OVER GLADES COUNTY LATE THIS AFTERNOON. LOW LEVEL MOISTURE WILL INCREASE SLIGHTLY TONIGHT WITH THE STRENGTHENING SOUTHEAST WINDS...AND DEWPOINTS WILL CREEP UP TOWARDS 70F. OVERNIGHT LOWS WILL BE WARM...WITH TEMPERATURES IN THE MID/UPPER 60S INTERIOR TO LOW TO MID 70S FOR THE EAST COAST METRO AREAS. MONDAY AND TUESDAY...THE LARGE AND ANOMALOUS UPPER LEVEL LOW IS FORECAST TO BE LOCATED ACROSS THE MIDDLE OF THE NATION...WITH THE UPPER LEVEL RIDGE OVER SOUTH FLORIDA AND UP THE EASTERN SEA BOARD. THE BAND OF LOW/MID LEVEL DRY AIR WILL REMAIN OVER THE SOUTHERN HALF OF THE REGION...AND ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS IS POSSIBLE ACROSS THE LAKE REGION ON MONDAY. THE BAND OF DRIER AIR IS FORECAST TO PUSH INTO THE WESTERN ATLANTIC BY TUESDAY EVENING...AND SLIGHT CHANCES OF SHOWERS AND STORMS RETURN TO MOST OF THE INTERIOR. TEMPERATURES WILL BE WARM WITH HIGHS IN THE MID 80S TO LOWER 90S. LOWS ARE FORECAST TO BE IN THE MID/UPPER 60S INTERIOR TO LOW/MID 70S EAST COAST METRO AREAS. WEDNESDAY AND THURSDAY...LARGE UPPER LOW/TROUGH WILL REMAIN UPPER MIDWEST/GREAT LAKES REGION...WITH UPPER RIDGING HOLDING ON ACROSS SOUTH FLORIDA. A FRONTAL BOUNDARY IS FORECAST TO PUSH INTO NORTHERN FLORIDA AND STALL. MOISTURE IS FORECAST TO INCREASE AND ISOLATED/SCATTERED SHOWERS AND STORMS ARE FORECAST MAINLY ACROSS THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. THE BEST CHANCES OF RAIN WILL REMAIN FROM THE LAKE REGION NORTHWARD CLOSER TO THE FRONTAL BOUNDARY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND SIMILAR TO THE EARLIER IN THE WEEK. FRIDAY AND SATURDAY...MODELS BEGIN TO DIVERGE SLIGHTLY THE END OF THE WEEK INTO NEXT WEEKEND...DUE TO THEIR HANDLING OF SOUTHERN STREAM ENERGY MOVING OUT OF THE INTERMOUNTAIN WEST. THE ECMWF IS SLIGHTLY DEEPER WITH THE UPPER TROUGH AS IT PHASES THE SHORTWAVE ENERGY WITH THE TROUGH...AND DEVELOPS AN AREA OF LOW PRESSURE ALONG THE FRONTAL BOUNDARY OVER THE GULF OF MEXICO ON FRIDAY. THIS RESULTS IN THE FRONT PUSHING BACK NORTHWARD INTO THE PANHANDLE ON FRIDAY...BEFORE FINALLY PUSHING TOWARDS THE REGION THE LATTER PART OF NEXT WEEKEND. THE GFS HAS THE FRONT NEAR THE REGION ON FRIDAY AND OVER THE REGION ON SATURDAY...WITH HIGHER RAIN CHANCES. FOR NOW...KEPT LOW END CHANCES OF SHOWERS AND STORMS FOR FRIDAY AND SATURDAY. && .AVIATION... VFR CONDITIONS DOMINATE THROUGH MONDAY. SLIGHTLY STRONGER SOUTHEAST FLOW THIS AFTERNOON SHOULD MEAN LITTLE SEA-BREEZE IMPACT FOR EASTERN TERMINALS...WITH GULF-BREEZE INTRUSION EXPECTED IN NAPLES AFTER 18Z...SHIFTING WINDS TO W. && .MARINE... A WEAK PRESSURE GRADIENT CONTINUES ACROSS THE REGIONAL WATERS WITH MORE SOUTHEASTERLY FLOW RETURNING TODAY INTO EARLY NEXT WEEK. IN GENERAL SEAS ARE EXPECTED TO BE 3 FEET OR LESS TODAY WITH JUST A GRADUAL INCREASE IN WINDS AND SEAS EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 88 73 85 75 / 0 10 10 0 FORT LAUDERDALE 87 77 86 78 / 0 0 0 10 MIAMI 89 76 87 76 / 0 0 10 10 NAPLES 89 70 89 71 / 10 10 10 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE...84/AK AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
249 AM EDT SUN APR 27 2014 .SHORT TERM...TODAY AND TONIGHT...LATEST HRRR AND NARRE MODELS SHOW LOW CLOUDS AND FOG FORMING ALONG FL GULF COAST AND FL ATLANTIC COAST EARLY THIS MORNING. FOG/CLOUDS SHOULD BURN OFF SHORTLY AFTER SUNRISE AGAIN. WEAK STATIONARY FRONT OVER THE AREA WILL DISSIPATE TODAY AS SHORT WAVE RIDGE AXIS APPROACHES FROM THE WEST. WEAK WINDS WILL ALLOW SEABREEZES TO MOVE INLAND REACHING THE INTERIOR BY LATE AFTERNOON AND EARLY EVENING. HAVE KEPT SLGT CHANCE TO CHANCE AFTN/EVEN POPS AS MOISTURE GRADUALLY INCREASES TODAY. A WEAK MID LEVEL IMPULSE WILL RIDE OVER THE RIDGE POSSIBLY ENHANCING SHRA/TSRA ESPECIALLY NEAR THE SEABREEZE COLLISION. TEMPERATURES WILL BE WARM AGAIN WITH MAX TEMPS APPROACHING 90 DEGREES WELL INLAND AND AROUND 80 COAST. MIN TEMPS TONIGHT WILL BE IN THE 60S. .MONDAY THROUGH TUESDAY...LOW AMPLITUDE RIDGING MONDAY WILL FLATTEN MONDAY NIGHT/TUESDAY AS A LARGE TROUGH MOVES ACROSS THE MISSISSIPPI VALLEY. DEEP MOISTURE WILL REMAIN WELL TO THE WEST...SO PRECIP WILL BE CONFINED TO THE AFTN/EARLY EVENING HOURS WITH MAINLY SEABREEZE AND SMALL SCALE INTERACTIONS AS THE TRIGGERS. WILL KEEP POPS SLIGHT CHANCE. HIGH TEMPERATURES WILL RANGE FROM THE UPPER 80S/AROUND 90 INLAND TO THE LOWER/MID 80S COAST. LOWS IN THE MID/UPPER 60S WILL GENERALLY PREVAIL. .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ECMWF/GFS COMING INTO A BIT BETTER AGREEMENT WITH THE TROUGH AND ASSOCIATED SURFACE COLD FRONT...BRINGING AN INITIAL SHORTWAVE ACROSS SE GA WEDNESDAY...SLOWLY BRINGING THE TROUGH INTO THE REGION LATE IN THE WEEK...WITH THE SYSTEMS COLD FRONT CROSSING THE REGION SATURDAY. STILL SOME TIMING DIFFERENCES...SO WILL KEEP POPS CHANCE FROM LATE WEDNESDAY INTO SATURDAY...WITH LOWERING POPS SATURDAY NW TO SE DURING THE DAY. WITH THE MID/UPPER LEVEL FORCING PROGGED TO BE STRETCHING OUT AS IT CROSSES THE REGION...DO NOT EXPECT ORGANIZED SEVERE STORMS LIKE THE SYSTEM IS CURRENTLY PRODUCING IN THE CENTRAL PLAINS. ABOVE NORMAL TEMPERATURES WEDNESDAY WILL GRADUALLY COOL TO NEAR NORMAL BY THE WEEKEND. && .AVIATION... VFR CONDITIONS WILL GENERALLY PREVAIL. PATCHES OF MVFR BR WILL BE POSSIBLE ACROSS THE NE FL TERMINALS 08-12Z. ISOLATED TO WIDELY SCATTERED SHOWERS WILL LIKELY DEVELOP ALONG THE SEABREEZE THIS AFTN...WILL USE VCSH FOR GNV/VQQ. ISOLATED MVFR CIGS CANNOT BE RULED OUT...BUT CONFIDENCE IS TOO SMALL TO INCLUDE IN THE TERMINALS FOR NOW. && .MARINE...SURFACE HIGH PRESSURE OFF THE EAST COAST WILL RESULT IN A S TO SE FLOW THE NEXT FEW DAYS ENHANCED BY AFTERNOON SEABREEZE FORMATION. THUNDERSTORM ACTIVITY WILL INCREASE MID TO LATE WEEK AS A SLOW MOVING COLD FRONT APPROACHES THE EAST COAST. WINDS WILL LIKELY INCREASE TO CAUTION LEVELS...AND POSSIBLY TO NEAR ADVISORY CONDITIONS OFFSHORE TUESDAY THROUGH WEDNESDAY NIGHT. RIP CURRENTS: LOW RISK TODAY AND MONDAY. && .HYDROLOGY...MAJOR FLOOD STAGE REACHED AT THREE RIVER ESTATES ON THE SUWANNEE RIVER...THIS WILL PERSIST THROUGH THE WEEK. MINOR TO MODERATE FLOODING WILL ALSO CONTINUE ON SEVERAL OTHER NE FL/SE GA RIVERS. && .PRELIMINARY POINT TEMPS/POPS... AMG 88 63 88 65 / 30 20 10 10 SSI 79 67 80 67 / 10 10 10 20 JAX 88 63 89 67 / 20 10 20 20 SGJ 81 67 84 67 / 10 10 20 20 GNV 89 66 88 65 / 30 20 20 20 OCF 89 65 89 65 / 30 20 20 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ ZIBURA/ALLEN/
AREA FORECAST DISCUSSION
NWS WICHITA KS
110 PM CDT SUN APR 27 2014 ...UPDATED FOR 18Z AVIATION DISCUSSION... .UPDATE... ISSUED AT 109 PM CDT SUN APR 27 2014 STILL SOME POTENTIAL FOR SURFACE-BASED THUNDERSTORM REDEVELOPMENT THIS AFTERNOON GENERALLY ALONG/EAST OF THE FLINT HILLS CORRIDOR. DRYLINE IS CONTINUING TO MIX EASTWARD...CURRENTLY ALONG THE I-135 CORRIDOR. SURFACE HEATING IN WAKE OF MORNING CONVECTION...IN CONCERT WITH 50S TO LOW 60S DEWPOINTS AND STEEPENING LAPSE RATES...OWING TO COOLING ALOFT ASSOCIATED WITH NEGATIVELY TILTED SHORTWAVE APPROACHING FROM THE WEST...WILL ALLOW FOR MLCAPE VALUES OF 1000-2000 J/KG AHEAD OF THE DRYLINE THIS AFTERNOON. TAKING INTO ACCOUNT AMPLE DEEP LAYER SHEAR...CONDITIONS WILL BE FAVORABLE FOR ORGANIZED STRONG/SEVERE STORMS. HOWEVER...SINCE BEST UPPER FORCING IS PUSHING OFF TO THE NORTHEAST...QUESTIONS ARISE WHETHER ENOUGH DRYLINE CONVERGENCE WILL BE PRESENT FOR ACTIVITY TO FORM...WHICH IS SUPPORTED BY LATEST HRRR. IF A FEW STORMS CAN MANAGE TO FORM...QUARTER-GOLFBALL SIZE HAIL AND 70 MPH WINDS WILL BE POSSIBLE. COULD ALSO SEE AN ISOLATED TORNADO GIVEN STEEP LOW- LEVEL LAPSE RATES...AMPLE LOW-LEVEL CAPE...AND STRONG LOW TO DEEP LAYER WIND FIELDS. LATEST MODEL GUIDANCE HAS SLOWED DRYLINE ADVANCEMENT QUITE A BIT...SO THUNDERSTORM THREAT COULD LINGER WELL INTO THE EVENING OVER FAR SOUTHEAST KS. ADK && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 STRONGER FORCING FOR ASCENT HAS ARRIVED EARLY THIS MORNING AS THE APPROACHING UPPER TROF TAKES ON A NEGATIVE TILT AS IT BEGINS TO MOVE OUT ACROSS THE HIGH PLAINS. SCATTERED STRONG CONVECTION HAS DEVELOPED WITHIN THE INCREASINGLY MOIST WARM SECTOR AHEAD OF THE SURFACE DRY-LINE...WITH THE HRRR AND GFS SUPPORTING CONTINUED DEVELOPMENT DURING THE MORNING GENERALLY ALONG/EAST OF THE I-135 CORRIDOR. MARGINALLY SEVERE STORMS WITH HAIL WILL BE POSSIBLE EARLY THIS MORNING. HOWEVER THE MAIN FOCUS FOR A MORE ROBUST AND HIGHER END SEVERE EPISODE WILL AFFECT PORTIONS OF SOUTHEAST KANSAS THIS AFTERNOON BEFORE THE DRY-LINE SWEEPS EAST OF THE AREA BY EARLY EVENING. ML CAPE VALUES OF 1500-2000J/KG AND STRONG SHEAR EXPECT TO RESIDE JUST EAST OF THE DRY-LINE WHERE THE CAP WILL BE ERODED MORE QUICKLY FOR SURFACE BASED CONVECTION DUE TO MID-LEVEL COLD ADVECTION WITH THE ASSOCIATED UPPER TROF. THIS WILL LIKELY RESULT IN STRONG TO SEVERE SURFACE BASED STORMS AS EARLY AS MIDDAY...WHICH WILL AFFECT SOUTHEAST KANSAS DURING THE AFTERNOON. THE RICHER LOW LEVEL MOISTURE WILL ALSO RESULT IN DECENT LOW LEVEL CAPE FOR MORE BUOYANT INITIAL UPDRAFTS WHERE SHEAR MAY COMBINE TO BE SUPPORTIVE OF A FEW TORNADIC STORMS BESIDES LARGE HAIL AND DAMAGING WINDS. THE LATEST TIMING OF THE DRY-LINE SHOULD PUSH MUCH OF THIS ACTIVITY EAST OF THE FORECAST AREA BY 21Z-23Z. THERE IS CONCERN BEHIND THE DRY-LINE THIS AFTERNOON FOR STRONG SOUTH-SOUTHWEST WINDS IN A DRIER AND DEEPLY MIXED LOWER TO MID-TROPOSPHERE. BESIDES A WIND ADVISORY AND FIRE WEATHER CONCERN...AREAS OF HAZE FROM BLOWING DUST AND PERHAPS SOME VISIBILITY RESTRICTIONS MAY RESULT ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. OBSERVATIONS FROM SOUTHEAST COLORADO INTO NORTHEAST NEW MEXICO AND THE TEXAS PANHANDLE ARE ALREADY REPORTING SOME OF THIS AS OF VERY EARLY THIS MORNING. THE DEEP OCCLUDING CYCLONE TO OUR NORTH ACROSS NEBRASKA WILL IMPACT OUR WEATHER INTO MONDAY...WITH GUSTY WINDS BECOMING DIURNALLY STRONGER DURING THE DAY AND LIKELY SUPPORTING ANOTHER WIND ADVISORY. THE CLOSED LOW WILL BROADEN AS IT DRIFTS NORTHEAST ACROSS THE MIDWEST INTO TUESDAY WITH AN UNSEASONABLY CHILLY AIRMASS AND WEAK INSTABILITY SHOWERS POSSIBLE ACROSS THE AREA. DARMOFAL .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 THE CLOSED LOW WILL GRADUALLY LOOSEN ITS GRIP ON THE AREA LATE IN THE WEEK AS IT MOVES EAST ACROSS THE GREAT LAKES WITH GRADUALLY MODERATING TEMPERATURES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 109 PM CDT SUN APR 27 2014 STILL ANTICIPATING POTENTIAL FOR A FEW ISOLATED TO WIDELY SCATTERED THUNDERSTORMS TO REDEVELOP GENERALLY ALONG/EAST OF THE FLINT HILLS THIS AFTERNOON AND PERSIST INTO THE EVENING...AS A DRYLINE AND ASSOCIATED STRONG UPPER TROUGH CONTINUES TO ADVANCE EAST. CONSEQUENTLY...HELD ONTO VCTS WORDING AT KCNU. OTHERWISE...STRONG/GUSTY SOUTH TO SOUTHWEST WINDS ARE ANTICIPATED AREAWIDE THROUGH THE AFTERNOON. WINDS SHOULD SLACKEN SOME OVERNIGHT BUT STILL REMAIN BREEZY OUT OF THE WEST/SOUTHWEST. LATER TONIGHT...MVFR TO LOW VFR CIGS WILL BE POSSIBLE...AS COLD ADVECTION COMMENCES IN WAKE OF A COLD FRONT. STRONG/GUSTY WEST TO NORTHWEST WINDS ANTICIPATED MONDAY...AS LOW PRESSURE SITS AND SPINS NORTH OF THE REGION. ADK && .FIRE WEATHER... ISSUED AT 229 AM CDT SUN APR 27 2014 A SIGNIFICANT FIRE WEATHER DAY IS POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS THIS AFTERNOON...AS VERY STRONG SOUTH-SOUTHWEST WINDS ARE EXPECTED BEHIND THE DRY-LINE. MUCH DRIER AIR AND THE STRONG WINDS WILL RESULT IN VERY HIGH GFDI VALUES AND EXTREME FIRE DANGER ROUGHLY ALONG AND WEST OF THE KANSAS TURNPIKE. IT WILL REMAIN WINDY INTO MONDAY WITH ELEVATED FIRE DANGER EXPECTED AGAIN FOR WESTERN PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS. KED && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 79 49 70 46 / 60 10 20 20 HUTCHINSON 78 47 69 44 / 40 10 20 20 NEWTON 77 47 68 45 / 60 10 20 20 ELDORADO 79 48 70 46 / 90 10 20 20 WINFIELD-KWLD 80 49 72 47 / 80 10 20 20 RUSSELL 75 44 65 42 / 10 20 20 30 GREAT BEND 75 45 66 42 / 10 10 20 30 SALINA 78 47 67 44 / 40 10 20 30 MCPHERSON 78 47 68 44 / 40 10 20 30 COFFEYVILLE 80 51 73 47 / 100 10 20 20 CHANUTE 79 50 71 46 / 100 20 20 20 IOLA 78 50 70 46 / 100 20 20 20 PARSONS-KPPF 80 50 72 47 / 100 20 20 20 && .ICT WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR KSZ032-033- 047>053-067>069-082-083-091>093. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ032-033-047>053- 067>069-082-083-091>093. WIND ADVISORY FROM 9 AM TO 7 PM CDT MONDAY FOR KSZ032-033- 047>053-067-068-082-083. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
620 AM CDT SUN APR 27 2014 ...UPDATED FOR 12Z AVIATION DISCUSSION... .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 STRONGER FORCING FOR ASCENT HAS ARRIVED EARLY THIS MORNING AS THE APPROACHING UPPER TROF TAKES ON A NEGATIVE TILT AS IT BEGINS TO MOVE OUT ACROSS THE HIGH PLAINS. SCATTERED STRONG CONVECTION HAS DEVELOPED WITHIN THE INCREASINGLY MOIST WARM SECTOR AHEAD OF THE SURFACE DRY-LINE...WITH THE HRRR AND GFS SUPPORTING CONTINUED DEVELOPMENT DURING THE MORNING GENERALLY ALONG/EAST OF THE I-135 CORRIDOR. MARGINALLY SEVERE STORMS WITH HAIL WILL BE POSSIBLE EARLY THIS MORNING. HOWEVER THE MAIN FOCUS FOR A MORE ROBUST AND HIGHER END SEVERE EPISODE WILL AFFECT PORTIONS OF SOUTHEAST KANSAS THIS AFTERNOON BEFORE THE DRY-LINE SWEEPS EAST OF THE AREA BY EARLY EVENING. ML CAPE VALUES OF 1500-2000J/KG AND STRONG SHEAR EXPECT TO RESIDE JUST EAST OF THE DRY-LINE WHERE THE CAP WILL BE ERODED MORE QUICKLY FOR SURFACE BASED CONVECTION DUE TO MID-LEVEL COLD ADVECTION WITH THE ASSOCIATED UPPER TROF. THIS WILL LIKELY RESULT IN STRONG TO SEVERE SURFACE BASED STORMS AS EARLY AS MIDDAY...WHICH WILL AFFECT SOUTHEAST KANSAS DURING THE AFTERNOON. THE RICHER LOW LEVEL MOISTURE WILL ALSO RESULT IN DECENT LOW LEVEL CAPE FOR MORE BUOYANT INITIAL UPDRAFTS WHERE SHEAR MAY COMBINE TO BE SUPPORTIVE OF A FEW TORNADIC STORMS BESIDES LARGE HAIL AND DAMAGING WINDS. THE LATEST TIMING OF THE DRY-LINE SHOULD PUSH MUCH OF THIS ACTIVITY EAST OF THE FORECAST AREA BY 21Z-23Z. THERE IS CONCERN BEHIND THE DRY-LINE THIS AFTERNOON FOR STRONG SOUTH-SOUTHWEST WINDS IN A DRIER AND DEEPLY MIXED LOWER TO MID-TROPOSPHERE. BESIDES A WIND ADVISORY AND FIRE WEATHER CONCERN...AREAS OF HAZE FROM BLOWING DUST AND PERHAPS SOME VISIBILITY RESTRICTIONS MAY RESULT ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. OBSERVATIONS FROM SOUTHEAST COLORADO INTO NORTHEAST NEW MEXICO AND THE TEXAS PANHANDLE ARE ALREADY REPORTING SOME OF THIS AS OF VERY EARLY THIS MORNING. THE DEEP OCCLUDING CYCLONE TO OUR NORTH ACROSS NEBRASKA WILL IMPACT OUR WEATHER INTO MONDAY...WITH GUSTY WINDS BECOMING DIURNALLY STRONGER DURING THE DAY AND LIKELY SUPPORTING ANOTHER WIND ADVISORY. THE CLOSED LOW WILL BROADEN AS IT DRIFTS NORTHEAST ACROSS THE MIDWEST INTO TUESDAY WITH AN UNSEASONABLY CHILLY AIRMASS AND WEAK INSTABILITY SHOWERS POSSIBLE ACROSS THE AREA. DARMOFAL .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 THE CLOSED LOW WILL GRADUALLY LOOSEN ITS GRIP ON THE AREA LATE IN THE WEEK AS IT MOVES EAST ACROSS THE GREAT LAKES WITH GRADUALLY MODERATING TEMPERATURES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 615 AM CDT SUN APR 27 2014 NUMEROUS SHOWERS AND THUNDERSTORMS WILL MOVE NORTHEAST ACROSS THE REGION THIS MORNING...AS A STRONG UPPER LEVEL STORM SYSTEM MOVES EASTWARD ACROSS THE CENTRAL PLAINS. A FEW OF THE STORMS COULD BECOME SEVERE ACROSS SOUTHEAST KANSAS. OTHERWISE LOW CLOUDS WILL QUICKLY CLEAR OUT FROM WEST TO EAST AS DRIER AIR PUSHES FROM THE WEST TODAY. SOUTHWEST WINDS WILL INCREASE DRAMATICALLY OVER CENTRAL/SOUTH CENTRAL KANSAS FOR THIS MORNING AND AFTERNOON...WITH GUSTS OVER 35KTS LIKELY. WINDS WILL DECREASE A BIT FOR THIS EVENING AND VEER MORE OUT TO THE WEST. JAKUB && .FIRE WEATHER... ISSUED AT 229 AM CDT SUN APR 27 2014 A SIGNIFICANT FIRE WEATHER DAY IS POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS THIS AFTERNOON...AS VERY STRONG SOUTH-SOUTHWEST WINDS ARE EXPECTED BEHIND THE DRY-LINE. MUCH DRIER AIR AND THE STRONG WINDS WILL RESULT IN VERY HIGH GFDI VALUES AND EXTREME FIRE DANGER ROUGHLY ALONG AND WEST OF THE KANSAS TURNPIKE. IT WILL REMAIN WINDY INTO MONDAY WITH ELEVATED FIRE DANGER EXPECTED AGAIN FOR WESTERN PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS. KED && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 79 49 70 46 / 40 10 20 20 HUTCHINSON 78 47 69 44 / 40 10 20 20 NEWTON 77 47 68 45 / 40 10 20 20 ELDORADO 79 48 70 46 / 50 10 20 20 WINFIELD-KWLD 80 49 72 47 / 50 10 20 20 RUSSELL 75 44 65 42 / 20 20 20 30 GREAT BEND 75 45 66 42 / 10 10 20 30 SALINA 78 47 67 44 / 40 10 20 30 MCPHERSON 78 47 68 44 / 40 10 20 30 COFFEYVILLE 80 51 73 47 / 60 10 20 20 CHANUTE 79 50 71 46 / 60 20 20 20 IOLA 78 50 70 46 / 60 20 20 20 PARSONS-KPPF 80 50 72 47 / 60 20 20 20 && .ICT WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR KSZ032-033-047>053-067>069-082-083-091>093. WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR KSZ032-033-047>053-067>069-082-083-091>093. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
229 AM CDT SUN APR 27 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 STRONGER FORCING FOR ASCENT HAS ARRIVED EARLY THIS MORNING AS THE APPROACHING UPPER TROF TAKES ON A NEGATIVE TILT AS IT BEGINS TO MOVE OUT ACROSS THE HIGH PLAINS. SCATTERED STRONG CONVECTION HAS DEVELOPED WITHIN THE INCREASINGLY MOIST WARM SECTOR AHEAD OF THE SURFACE DRY-LINE...WITH THE HRRR AND GFS SUPPORTING CONTINUED DEVELOPMENT DURING THE MORNING GENERALLY ALONG/EAST OF THE I-135 CORRIDOR. MARGINALLY SEVERE STORMS WITH HAIL WILL BE POSSIBLE EARLY THIS MORNING. HOWEVER THE MAIN FOCUS FOR A MORE ROBUST AND HIGHER END SEVERE EPISODE WILL AFFECT PORTIONS OF SOUTHEAST KANSAS THIS AFTERNOON BEFORE THE DRY-LINE SWEEPS EAST OF THE AREA BY EARLY EVENING. ML CAPE VALUES OF 1500-2000J/KG AND STRONG SHEAR EXPECT TO RESIDE JUST EAST OF THE DRY-LINE WHERE THE CAP WILL BE ERODED MORE QUICKLY FOR SURFACE BASED CONVECTION DUE TO MID-LEVEL COLD ADVECTION WITH THE ASSOCIATED UPPER TROF. THIS WILL LIKELY RESULT IN STRONG TO SEVERE SURFACE BASED STORMS AS EARLY AS MIDDAY...WHICH WILL AFFECT SOUTHEAST KANSAS DURING THE AFTERNOON. THE RICHER LOW LEVEL MOISTURE WILL ALSO RESULT IN DECENT LOW LEVEL CAPE FOR MORE BUOYANT INITIAL UPDRAFTS WHERE SHEAR MAY COMBINE TO BE SUPPORTIVE OF A FEW TORNADIC STORMS BESIDES LARGE HAIL AND DAMAGING WINDS. THE LATEST TIMING OF THE DRY-LINE SHOULD PUSH MUCH OF THIS ACTIVITY EAST OF THE FORECAST AREA BY 21Z-23Z. THERE IS CONCERN BEHIND THE DRY-LINE THIS AFTERNOON FOR STRONG SOUTH-SOUTHWEST WINDS IN A DRIER AND DEEPLY MIXED LOWER TO MID-TROPOSPHERE. BESIDES A WIND ADVISORY AND FIRE WEATHER CONCERN...AREAS OF HAZE FROM BLOWING DUST AND PERHAPS SOME VISIBILITY RESTRICTIONS MAY RESULT ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. OBSERVATIONS FROM SOUTHEAST COLORADO INTO NORTHEAST NEW MEXICO AND THE TEXAS PANHANDLE ARE ALREADY REPORTING SOME OF THIS AS OF VERY EARLY THIS MORNING. THE DEEP OCCLUDING CYCLONE TO OUR NORTH ACROSS NEBRASKA WILL IMPACT OUR WEATHER INTO MONDAY...WITH GUSTY WINDS BECOMING DIURNALLY STRONGER DURING THE DAY AND LIKELY SUPPORTING ANOTHER WIND ADVISORY. THE CLOSED LOW WILL BROADEN AS IT DRIFTS NORTHEAST ACROSS THE MIDWEST INTO TUESDAY WITH AN UNSEASONABLY CHILLY AIRMASS AND WEAK INSTABILITY SHOWERS POSSIBLE ACROSS THE AREA. DARMOFAL .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 229 AM CDT SUN APR 27 2014 THE CLOSED LOW WILL GRADUALLY LOOSEN ITS GRIP ON THE AREA LATE IN THE WEEK AS IT MOVES EAST ACROSS THE GREAT LAKES WITH GRADUALLY MODERATING TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1149 PM CDT SAT APR 26 2014 MAIN CONCERNS: STRONG WINDS...MORNING MVFR CIGS...THUNDERSTORMS. STORM SYSTEM WILL BEGIN LIFTING NORTHEASTWARD OUT OVER THE CENTRAL PLAINS LATE TONIGHT INTO SUNDAY. MVFR CEILINGS WILL LIKELY TRY TO DEVELOP UNDERNEATH THE STRONG SOUTHERLY LOW-LEVEL JET AXIS LATE TONIGHT INTO SUNDAY MORNING. WILL INITIALLY INCLUDE MVFR CIGS AT HUT...ICT...CNU WHERE HIGHEST CONFIDENCE EXISTS. SCATTERED THUNDERSTORMS MAY DEVELOP ACROSS SOUTH CENTRAL/SOUTHEAST KS LATE TONIGHT INTO THE MORNING HOURS SUNDAY. HAVE INCLUDED A TS MENTION AT HUT...ICT...AND CNU FROM 09Z ONWARD. SOUTHERLY WINDS WILL GUST TO AROUND 40 KNOTS OVERNIGHT INTO SUNDAY AREA-WIDE. SOUTHWESTERLY WINDS SHOULD DIMINISH SOME SUNDAY EVENING. JMC && .FIRE WEATHER... ISSUED AT 229 AM CDT SUN APR 27 2014 A SIGNIFICANT FIRE WEATHER DAY IS POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS THIS AFTERNOON...AS VERY STRONG SOUTH-SOUTHWEST WINDS ARE EXPECTED BEHIND THE DRY-LINE. MUCH DRIER AIR AND THE STRONG WINDS WILL RESULT IN VERY HIGH GFDI VALUES AND EXTREME FIRE DANGER ROUGHLY ALONG AND WEST OF THE KANSAS TURNPIKE. IT WILL REMAIN WINDY INTO MONDAY WITH ELEVATED FIRE DANGER EXPECTED AGAIN FOR WESTERN PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS. KED && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 79 49 70 46 / 30 10 20 20 HUTCHINSON 78 47 69 44 / 20 10 20 20 NEWTON 77 47 68 45 / 30 10 20 20 ELDORADO 79 48 70 46 / 40 10 20 20 WINFIELD-KWLD 80 49 72 47 / 40 10 20 20 RUSSELL 75 44 65 42 / 20 20 20 30 GREAT BEND 75 45 66 42 / 10 10 20 30 SALINA 78 47 67 44 / 30 10 20 30 MCPHERSON 78 47 68 44 / 20 10 20 30 COFFEYVILLE 80 51 73 47 / 60 10 20 20 CHANUTE 79 50 71 46 / 60 20 20 20 IOLA 78 50 70 46 / 60 20 20 20 PARSONS-KPPF 80 50 72 47 / 60 20 20 20 && .ICT WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR KSZ032-033-047>053-067>069-082-083-091>093. WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR KSZ032-033-047>053-067>069-082-083-091>093. && $$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1153 PM CDT Sat Apr 26 2014 .UPDATE... Issued at 941 PM CDT SAT APR 26 2014 00Z TOP sounding showed an elevated mixed layer capping off surface based convection. The dryline has retreated west this evening across western Kansas. Therefore have cut back on the precipitation chances until after midnight where chances will continue to increase after 09Z. Strengthening low level jet as well as isentropic lift in the 305K to 310k layer and increasing ascent ahead of the upper trough moving across the Rockies should kick off storms in the overnight hours. HRRR continues to develop convection from southwest and south central Kansas and then move it northeast into the cwa in the 09Z-11Z time period. Current forecast accounts for this scenario very well. && ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Sunday) Issued at 258 PM CDT SAT APR 26 2014 Focus on the period is the isolated severe storm potential early this evening, followed by scattered severe storms being possible early Sunday morning and afternoon. A strong and windy afternoon across northeast Kansas as temperatures warmed into the lower 80s. Wind gusts ahead of a deepening lee trough ranged between 30 and 40 mph during the late morning and afternoon hours. Dryline has setup across western Kansas as moisture pulls northward, noted by upper 50s to near 60 degrees in central Kansas, dropping to the low 20s in far western Kansas. For late this afternoon into early this evening, short and long term guidance is consistently indicating the dryline to bulge eastward into north central Kansas. Strong convergence along and just ahead of the boundary may provide just enough lift to erode the capping inversion in place over far north central areas. Surface based CAPE values increase to 1500 J/KG as effective bulk shear peaks near 45 kts. Strong boundary layer mixing by late afternoon lifts LCL heights to around 4000 feet. Current thinking is that isolated thunderstorms are possible over north central KS during the early evening hours (generally after 6 PM). The higher LCL heights and less than ideal moisture return leaves the tornado threat low for this evening. Main threat with these thunderstorms will be the large hail and localized damaging wind gusts. These storms are expected to track northeast into Nebraska through the evening hours. Conditions remain dry elsewhere. Moisture return and increased cloud cover keep lows mild in the middle to upper 60s. Moisture advection increases overnight into Sunday as the strong upper low lifts northeast through Colorado into northwest Kansas. Widespread, broad ascent increases over southern into portions of northeast Kansas generally after midnight as an 80 kt mid level jet streak rounds the base of the wave. The increasing lift combined with steepening mid level lapse rates and MUCAPE values approaching 3000 J/KG sets the stage for another cluster of thunderstorms to form in the vicinity of southern Kansas, tracking eastward across portions of north central and east central KS. Latest short term guidance is not as aggressive with widespread precip developing further north so have lowered pops to chance and kept highest chances south of Interstate 70. Main threats with these storms would be large hail and strong winds. Uncertainty increases from early morning through the afternoon on Sunday. Most guidance progs the dryline to surge eastward between 7 to 10 AM with showers and thunderstorms possible over the area, remaining elevated in nature due to the strong surface inhibition in place. A few storms may be severe with large hail and gusty winds possible. Main limiting factor would be if these storms create a stable surface layer, limiting surface based cells from developing in the afternoon. Daytime heating and sunshine would allow the surface instability to increase by afternoon, however the increasing surface moisture should hold the overcast skies for much of the day. Assuming convection impacts mainly areas just south of the CWA and perhaps north central areas, much of east central KS would remain precip free for a short time, resulting in a higher risk for severe weather during the late morning into the afternoon. By 1 PM the dryline is shown to be roughly along a line from Washington, to Clay Center, and Abilene. Increased chances for thunderstorms to likely east of this area as the weak capping inversion is able to erode as surface based instability raises to over 2000 J/KG. Maximizing bulk shear in excess of 50 kts suggest strong rotating updrafts, including supercells. The parallel orientation of the winds to the boundary suggest line segments with embedded areas of rotation are also possible. Individual cells stand the best chance of a tornado potential while other modes face a large hail and damaging wind hazard. Best areas to be impacted by these storms are along and east of highway 99 through the early evening as the storms and attendant dryline push eastward. In addition to the thunder, southerly winds remain gusty through Sunday with sustained speeds between 20 and 25 mph with gusts near 35 mph. Dewpoints sharply falling over north central Kansas during the late afternoon Sunday raise the fire danger to very high. .LONG TERM...(Sunday Night through Saturday) Issued at 258 PM CDT SAT APR 26 2014 Line of storms moving through far eastern Kansas Sunday afternoon may linger into the evening hours and have kept a chance far east to accommodate that potential. Dryline and unstable air push eastward, leaving area under northwest flow through the boundary layer Monday and Monday night. A cooler day expected with highs in the 60s. Chance for rain returns on Tuesday as moisture sags southward as upper low drops into the Central Plains. Accumulations are forecast to be light. Repeat performance each day Thursday and again Friday as lobes of energy rotate around the upper trof over the Great Lakes states and keep rounds of clouds, showers, and cool temperatures over the area. May see some improvement by the weekend as trof makes slow eastward progress and temperatures could come back up into the 60s. Overnight lows from the upper 30s on Wednesday night come into the lower 40s by Thursday night and Friday night. && .AVIATION...(For the 06Z TAFs through 06Z Sunday Night) Issued at 1153 PM CDT SAT APR 26 2014 MVFR stratus cigs are expected to form or move in from the south in the 09Z-11Z period. In addition convection is likely to develop with an increase in areal extent in the 11Z-18Z time period and have included a tempo group for now. Surface winds south to southeast will increase to around 18kts with gusts to near 28 kts. Dry line timing still not solid but looks like it will move through MHK around 18Z and TOP and FOE in the 20Z to 21Z time frame. Skies become vfr after 23Z but winds will remain gusty from the south. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...53 SHORT TERM...Bowen LONG TERM...67 AVIATION...53
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1125 PM EDT MON APR 28 2014 .UPDATE... ISSUED AT 1115 PM EDT MON APR 28 2014 SHOWERS AND THUNDERSTORMS CONTINUE TO GRADUALLY MOVE NORTHEAST TOWARD EASTERN KENTUCKY. MODEL GUIDANCE INDICATES THE BAND OF CONVECTION MOVING ACROSS THE AREA OVERNIGHT AND A QUICKER TAPERING OFF FROM WEST TO EAST TOWARD DAWN THAN THE PREVIOUS FORECAST. HOWEVER...SOUTHEAST FLOW ESPECIALLY INTO OUR EASTERN COUNTIES SEEMS TO BE LIMITING THE EASTWARD PROGRESS. ALSO... INSTABILITY DECREASES TO THE EAST AND NORTHEAST. AT THIS POINT... SOME STRONG STORMS APPEAR POSSIBLE...MAINLY ACROSS THE WESTERN PART OF THE CWA AND LOCALLY HEAVY RAIN MAY BE THE PRIMARY THREAT FOR THE DURATION OF THE NIGHT. THE FURTHER EAST AND SOUTHEAST...THE DOWNSLOPE FLOW SHOULD CUT INTO RAINFALL AMOUNTS. THE SOUTH SOUTHEAST FLOW ON THE HIGHER TERRAIN NEAR VA COULD BE GUSTY AT TIMES AND SOME GUSTS AS HIGH AS 30 TO 40 MPH WILL BE POSSIBLE... WITH SUSTAINED WINDS IN THE 15 TO 25 MPH RANGE AT TIMES. UPDATE ISSUED AT 655 PM EDT MON APR 28 2014 THE LULL CONTINUES WITH THE STORMS. JKL AWAITS THE DEVELOPMENT FROM THE WEST AND THEN A PUSH EAST THROUGH THE NIGHT PER THE LATEST RAP AND HRRR MODELS. AS SUCH...HAVE DROPPED THE TORNADO WATCH IN THE FAR SOUTHEAST. ANY REAL THREAT OF SEVERE WEATHER WILL HOLD OFF UNTIL LATER IN THE EVENING. HAVE UPDATED THE POPS/WX GRIDS TO REFLECT THIS TIMING AND ALSO FINE TUNED THE T/TD ONES BASED ON THE LATEST OBS AND TRENDS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 425 PM EDT MON APR 28 2014 19Z SFC ANALYSIS SHOWS THE DEEP AREA OF LOW PRESSURE SPINNING OVER THE CENTRAL PLAINS. THIS SYSTEM/S WARM FRONT IS LAID OUT TO THE EAST JUST NORTH OF THE OHIO RIVER. THIS PLACES EAST KENTUCKY WELL INTO TO THE BROAD WARM SECTOR AND THUS RIPE FOR PERIODS OF SHOWERS AND THUNDERSTORMS. EARLIER SUNSHINE IN THE FAR EAST LED TO WARMER TEMPERATURES AND THIS IS HELPING STORMS SUSTAIN THEMSELVES NEAR THE VIRGINIA BORDER. MEANWHILE...MUCH COOLER TEMPERATURES IN THE REST OF THE CWA...DUE TO THE COLD POOL FROM THE EARLIER MCS TO THE WEST AND MORE EXTENSIVE CLOUD COVER...HAS KEPT THE CONVECTION TAME THERE...FOR NOW. DEWPOINTS REMAIN IN THE UPPER 50S TO LOWER 60S THROUGHOUT THE AREA WHILE THE WINDS ARE RATHER VARIABLE WITH OCCASIONAL SOUTH TO SOUTHWEST GUSTS TO 20 KTS...OUTSIDE OF STORMS. THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE DEEP UPPER LOW TRANSITIONING INTO THE MID MISSISSIPPI VALLEY TONIGHT AND SPREADING WAVES OF ENERGY CLUSTERS OVER EAST KENTUCKY AS IT DOES SO. THE BROAD CLOSED LOW THEN LIFTS NORTH INTO THE WESTERN GREAT LAKES LATER TUESDAY WHILE ONE LAST BATCH OF ENERGY RIDES THROUGH KENTUCKY DURING THE NIGHT. GIVEN THE MODEL AGREEMENT...HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE NAM12 AND HRRR FOR THE NEAR TERM DETAILS. SENSIBLE WEATHER WILL FEATURE PERIODS OF SHOWERS AND THUNDERSTORMS THROUGH THE SHORT TERM PORTION OF THE FORECAST. EACH NEW CLUSTER WILL HAVE A CHANCE TO BECOME SEVERE DEPENDING ON THE INSTABILITY LEFT BEHIND BY EARLIER STORMS AND CLEARING THAT CAN TAKE PLACE DURING THE DAYLIGHT HOURS. THIS WAS WHAT SET UP THE STORMS FOR FAR EAST KENTUCKY THIS AFTERNOON. EXPECT THESE TO CLEAR OUT OVER THE NEXT HOUR OR SO. ABOUT THAT TIME...THE NEXT ROUND OF STORMS SHOULD BE DEVELOPING IN SOUTH CENTRAL KENTUCKY AND WORKING TO MOVE NORTHEAST INTO EAST KENTUCKY LATER IN THE EVENING. STORMS WILL CONTINUE THROUGH THE NIGHT AS THE SET UP REMAINS INTACT. THE ACTUAL COVERAGE AND TIMING OF THESE LATER EVENTS WILL BE PARTIALLY DEPENDENT ON THE EARLIER EVOLUTION SO IT BECOMES HARDER TO PIN POINT. DO EXPECT THIS OVERNIGHT WAVE OF STORMS TO MOVE ON THROUGH TOWARDS DAWN AND EARLY TUESDAY MORNING IN FAR EASTERN PARTS OF THE STATE. ISOLATED TRAINING AND HEAVY RAINS WILL BE POSSIBLE THROUGH THE NIGHT...POSSIBLY RESULTING IN A FLASH FLOOD THREAT. THIS WILL CONTINUE TO BE HIGHLIGHTED IN THE HWO AND SPS. AFTER A MIDDAY LULL ON TUESDAY...LOW TOPPED STORMS SHOULD DEVELOP ACROSS EAST KENTUCKY BY LATE AFTERNOON WITH A CONTINUING POTENTIAL TO BE SEVERE...INCLUDING A SLIGHT TORNADO THREAT DUE TO FAVORABLE WIND SHEAR IN THE LOW LEVELS. THE MORE SUNSHINE THAT MANAGES TO OCCUR DURING THE DAY TUESDAY WILL PLAY INTO HOW STRONG THE STORMS COULD BECOME. THE SYSTEM/S COLD FRONT WILL SWEEP THROUGH LATER THAT NIGHT AND SHOULD END THE RISK FOR SEVERE WEATHER AND ALSO WIND DOWN THE THUNDER CHANCES. USED THE CONSSHORT AS A STARTING POINT FOR THE GRIDS THROUGH THE NEXT 24 HOURS WITH THE CONSALL THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE NUMBERS MAINLY TO CAPTURE THE CURRENT CONDITIONS AND TRENDS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL GUIDANCE THROUGH THE FORECAST. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 330 PM EDT MON APR 28 2014 MODELS REMAIN IN GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER AIR PATTERN THROUGH THE MIDDLE AND END OF THE WEEK. THE LARGE UPPER LOW OVER THE UPPER MS VALLEY WILL MAKES ITS WAY INTO THE GREAT LAKES REGION BY THURSDAY...AND THEN ON INTO CANADA BY FRIDAY. AFTER THIS THERE WILL BE OCCASIONAL SHORT WAVE TROUGHS PASSING BY AS A MEAN LONG WAVE TROUGH REMAINS OVER THE EASTERN PART OF THE U.S. INTO EARLY NEXT WEEK. IT DOES APPEAR THE FLOW WILL BE SLOWLY DEAMPLIFYING THOUGH. HIGHER RAIN AND THUNDERSTORMS CHANCES WILL LINGER INTO THE DAY WEDNESDAY...MAINLY IN THE EASTERN PART OF THE FORECAST AREA. THE DEEPER MOISTURE AND FORCING WILL BE EXITING THE AREA ON WEDNESDAY...BUT MAINLY DIURNAL SHOWER CHANCES WILL LINGER INTO THE WEEKEND. WITH A MEAN TROUGH OVER THE AREA TEMPERATURES WILL ALSO AVERAGE BELOW NORMAL FOR THE END OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL BE WARMING LATE IN THE WEEKEND AND INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 715 PM EDT MON APR 28 2014 VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE AREA THROUGH MID EVENING. THE NEXT STRONG TO SEVERE CLUSTER OF SHOWERS AND STORMS MOVES INTO THE AREA BETWEEN 02 AND 04Z. HAVE GONE WITH MVFR TO IFR CEILINGS AND VISIBILITY THROUGH MUCH OF THE NIGHT AND INTO EARLY TUESDAY MORNING WITH THIS OVERNIGHT ROUND OR TWO OF STORMS. CONDITIONS IMPROVE TEMPORARILY INTO MIDDAY TUESDAY WITH VFR CIGS AND VIS EXPECTED FOR A TIME. WINDS WILL BE OUT OF THE SOUTH FOR MUCH OF THE PERIOD WITH GUSTS UP TO 20 KTS POSSIBLE...OUTSIDE OF AND STORMS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
715 PM EDT MON APR 28 2014 .UPDATE... ISSUED AT 655 PM EDT MON APR 28 2014 THE LULL CONTINUES WITH THE STORMS. JKL AWAITS THE DEVELOPMENT FROM THE WEST AND THEN A PUSH EAST THROUGH THE NIGHT PER THE LATEST RAP AND HRRR MODELS. AS SUCH...HAVE DROPPED THE TORNADO WATCH IN THE FAR SOUTHEAST. ANY REAL THREAT OF SEVERE WEATHER WILL HOLD OFF UNTIL LATER IN THE EVENING. HAVE UPDATED THE POPS/WX GRIDS TO REFLECT THIS TIMING AND ALSO FINE TUNED THE T/TD ONES BASED ON THE LATEST OBS AND TRENDS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 425 PM EDT MON APR 28 2014 19Z SFC ANALYSIS SHOWS THE DEEP AREA OF LOW PRESSURE SPINNING OVER THE CENTRAL PLAINS. THIS SYSTEM/S WARM FRONT IS LAID OUT TO THE EAST JUST NORTH OF THE OHIO RIVER. THIS PLACES EAST KENTUCKY WELL INTO TO THE BROAD WARM SECTOR AND THUS RIPE FOR PERIODS OF SHOWERS AND THUNDERSTORMS. EARLIER SUNSHINE IN THE FAR EAST LED TO WARMER TEMPERATURES AND THIS IS HELPING STORMS SUSTAIN THEMSELVES NEAR THE VIRGINIA BORDER. MEANWHILE...MUCH COOLER TEMPERATURES IN THE REST OF THE CWA...DUE TO THE COLD POOL FROM THE EARLIER MCS TO THE WEST AND MORE EXTENSIVE CLOUD COVER...HAS KEPT THE CONVECTION TAME THERE...FOR NOW. DEWPOINTS REMAIN IN THE UPPER 50S TO LOWER 60S THROUGHOUT THE AREA WHILE THE WINDS ARE RATHER VARIABLE WITH OCCASIONAL SOUTH TO SOUTHWEST GUSTS TO 20 KTS...OUTSIDE OF STORMS. THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE DEEP UPPER LOW TRANSITIONING INTO THE MID MISSISSIPPI VALLEY TONIGHT AND SPREADING WAVES OF ENERGY CLUSTERS OVER EAST KENTUCKY AS IT DOES SO. THE BROAD CLOSED LOW THEN LIFTS NORTH INTO THE WESTERN GREAT LAKES LATER TUESDAY WHILE ONE LAST BATCH OF ENERGY RIDES THROUGH KENTUCKY DURING THE NIGHT. GIVEN THE MODEL AGREEMENT...HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE NAM12 AND HRRR FOR THE NEAR TERM DETAILS. SENSIBLE WEATHER WILL FEATURE PERIODS OF SHOWERS AND THUNDERSTORMS THROUGH THE SHORT TERM PORTION OF THE FORECAST. EACH NEW CLUSTER WILL HAVE A CHANCE TO BECOME SEVERE DEPENDING ON THE INSTABILITY LEFT BEHIND BY EARLIER STORMS AND CLEARING THAT CAN TAKE PLACE DURING THE DAYLIGHT HOURS. THIS WAS WHAT SET UP THE STORMS FOR FAR EAST KENTUCKY THIS AFTERNOON. EXPECT THESE TO CLEAR OUT OVER THE NEXT HOUR OR SO. ABOUT THAT TIME...THE NEXT ROUND OF STORMS SHOULD BE DEVELOPING IN SOUTH CENTRAL KENTUCKY AND WORKING TO MOVE NORTHEAST INTO EAST KENTUCKY LATER IN THE EVENING. STORMS WILL CONTINUE THROUGH THE NIGHT AS THE SET UP REMAINS INTACT. THE ACTUAL COVERAGE AND TIMING OF THESE LATER EVENTS WILL BE PARTIALLY DEPENDENT ON THE EARLIER EVOLUTION SO IT BECOMES HARDER TO PIN POINT. DO EXPECT THIS OVERNIGHT WAVE OF STORMS TO MOVE ON THROUGH TOWARDS DAWN AND EARLY TUESDAY MORNING IN FAR EASTERN PARTS OF THE STATE. ISOLATED TRAINING AND HEAVY RAINS WILL BE POSSIBLE THROUGH THE NIGHT...POSSIBLY RESULTING IN A FLASH FLOOD THREAT. THIS WILL CONTINUE TO BE HIGHLIGHTED IN THE HWO AND SPS. AFTER A MIDDAY LULL ON TUESDAY...LOW TOPPED STORMS SHOULD DEVELOP ACROSS EAST KENTUCKY BY LATE AFTERNOON WITH A CONTINUING POTENTIAL TO BE SEVERE...INCLUDING A SLIGHT TORNADO THREAT DUE TO FAVORABLE WIND SHEAR IN THE LOW LEVELS. THE MORE SUNSHINE THAT MANAGES TO OCCUR DURING THE DAY TUESDAY WILL PLAY INTO HOW STRONG THE STORMS COULD BECOME. THE SYSTEM/S COLD FRONT WILL SWEEP THROUGH LATER THAT NIGHT AND SHOULD END THE RISK FOR SEVERE WEATHER AND ALSO WIND DOWN THE THUNDER CHANCES. USED THE CONSSHORT AS A STARTING POINT FOR THE GRIDS THROUGH THE NEXT 24 HOURS WITH THE CONSALL THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE NUMBERS MAINLY TO CAPTURE THE CURRENT CONDITIONS AND TRENDS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL GUIDANCE THROUGH THE FORECAST. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 330 PM EDT MON APR 28 2014 MODELS REMAIN IN GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER AIR PATTERN THROUGH THE MIDDLE AND END OF THE WEEK. THE LARGE UPPER LOW OVER THE UPPER MS VALLEY WILL MAKES ITS WAY INTO THE GREAT LAKES REGION BY THURSDAY...AND THEN ON INTO CANADA BY FRIDAY. AFTER THIS THERE WILL BE OCCASIONAL SHORT WAVE TROUGHS PASSING BY AS A MEAN LONG WAVE TROUGH REMAINS OVER THE EASTERN PART OF THE U.S. INTO EARLY NEXT WEEK. IT DOES APPEAR THE FLOW WILL BE SLOWLY DEAMPLIFYING THOUGH. HIGHER RAIN AND THUNDERSTORMS CHANCES WILL LINGER INTO THE DAY WEDNESDAY...MAINLY IN THE EASTERN PART OF THE FORECAST AREA. THE DEEPER MOISTURE AND FORCING WILL BE EXITING THE AREA ON WEDNESDAY...BUT MAINLY DIURNAL SHOWER CHANCES WILL LINGER INTO THE WEEKEND. WITH A MEAN TROUGH OVER THE AREA TEMPERATURES WILL ALSO AVERAGE BELOW NORMAL FOR THE END OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL BE WARMING LATE IN THE WEEKEND AND INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 715 PM EDT MON APR 28 2014 VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE AREA THROUGH MID EVENING. THE NEXT STRONG TO SEVERE CLUSTER OF SHOWERS AND STORMS MOVES INTO THE AREA BETWEEN 02 AND 04Z. HAVE GONE WITH MVFR TO IFR CEILINGS AND VISIBILITY THROUGH MUCH OF THE NIGHT AND INTO EARLY TUESDAY MORNING WITH THIS OVERNIGHT ROUND OR TWO OF STORMS. CONDITIONS IMPROVE TEMPORARILY INTO MIDDAY TUESDAY WITH VFR CIGS AND VIS EXPECTED FOR A TIME. WINDS WILL BE OUT OF THE SOUTH FOR MUCH OF THE PERIOD WITH GUSTS UP TO 20 KTS POSSIBLE...OUTSIDE OF AND STORMS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GREIF LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
425 PM EDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 355 PM EDT SUN APR 27 2014 STARTING INTO AN ACTIVE PERIOD DURING THE SHORT TERM. A SURFACE LOW PRESSURE SYSTEM WILL REMAIN OVER THE CENTRAL PLAINS THIS EVENING...WHILE SEVERAL WAVES OF ENERGY WILL CONTINUE TO ROTATE AROUND THIS SYSTEM. EASTERN KY WILL REMAIN IN THE WARM SECTOR...WITH A WARM FRONT POSITIONED ACROSS MUCH OF THE STATE. MEANWHILE...WESTERN AND CENTRAL KY WILL FIND THEMSELVES POSITIONED BETWEEN THE WARM FRONT AND COLD FRONT...WITH WARM UNSTABLE AIR CONTINUING TO FILTER IN AND ABUNDANT MOISTURE TO ACCOMPANY. WHILE NOT MUCH PROGRESSION IS EXPECTED THIS AFTERNOON OR TONIGHT IN TERMS OF THE SURFACE LOW AND THE ASSOCIATED FRONTS...THE INCREASED INSTABILITY DURING THE AFTERNOON WILL WORK TO HELP ANY CONVECTIVE DEVELOPMENT TO SPREAD EASTWARD SLOWLY. LATEST HIRES MODELS...INCLUDING THE NAM12/HRRR/AND ECMWF ALL POINT AT PRECIP ENTERING INTO EASTERN KY BETWEEN 0 AND 6Z AND THEN CONTINUING EASTWARD THROUGHOUT THE NIGHT. IT IS ALSO AROUND THIS POINT THAT GFS40 AND NAM12 FORECAST SOUNDINGS SHOW SOME IMPRESSIVE LOW LEVEL SHEER IN PORTIONS OF EASTERN KY. WHILE LINGERING DRY LOW LEVEL AIR AND SE DOWNSLOPE WINDS COULD WORK TO HOLD OFF SOME PRECIP IN THE EVENING...EXPECT THAT ISOLATED TO SCATTERED SHOWERS WILL DEVELOP. IN DOING SO...MOISTENING OF THE LOW LEVELS WILL BE ENOUGH TO ALLOW UNSTABLE AIR TO RISE AND THUNDERSTORMS TO DEVELOP. IN ADDITION...BASED ON STRONG STORMS THAT HAVE DEVELOPED UPSTREAM...HAVE KEPT THUNDER AS THE PREDOMINATE WX TYPE THIS EVENING AND THROUGH THE NIGHT. BETWEEN 3Z AND 12Z MONDAY...CHANCE POPS WILL OVERSPREAD THE AREA. HOWEVER...LATEST HI-RES GUIDANCE IS POINTING AT A DRY POCKET DEVELOPING AS DOWNSLOPE FLOW INCREASES SLIGHTLY ACROSS THE SOUTHEAST PORTION OF THE STATE. LATEST RUC13 OMEGA IS ALSO SUPPORTIVE OF THIS IDEA...SHOWING DOWNWARD MOTION ACROSS THE SE PORTION OF THE STATE BY 9Z. THE QUESTION THEN WILL BE...HOW MUCH WILL THIS DOWNSLOPING INHIBIT ANY STORM DEVELOPMENT? HOW FAR INTO EASTERN KY COULD IT POTENTIALLY INHIBIT STORM GROWTH AND RAIN...AND WILL WE STILL EXPECT SOME ISOLATED TO SCATTERED CHANCES...OR WILL DOWNSLOPE CUT OFF POTENTIAL ALL TOGETHER? UNFORTUNATELY...THESE ARE ALL QUESTIONS WHICH CAN/T REALLY BE ANSWERED UNTIL THE MAIN CONVECTION REACHES OUR AREA. UNTIL THEN...WILL TRY TO PLAY ON THIS THINKING...AND TREND DOWN POPS SLIGHTLY FOR THE SE PORTION OF THE CWA. DURING THE DAY TOMORROW...SURFACE LOW WILL HAVE PROGRESSED ONLY SLIGHTLY EASTWARD...THOUGH THE SURFACE COLD FRONT WILL HAVE ENTERED INTO THE MISSISSIPPI VALLEY REGION. WITH THE FORCING SO GREAT IN PROXIMITY TO THIS FRONT...AND A STRONG PULL OF GULF MOISTURE...EXPECT SHOWERS/TSRA TO OVERCOME THE DOWNSLOPING PULL. ESPECIALLY IF WINDS SHIFT MORE SOUTHERLY FOR A PERIOD OF TIME...COULD SEE MORE WIDESPREAD DEVELOPMENT ACROSS THIS AREA. UNFORTUNATELY...EVEN THE HI-RES MODELS ARE SHOWING SOME DISAGREEMENT ON THE EXTENT AND MAGNITUDE OF PRECIP FOR TOMORROW...SO HAVE TRIED TO STICK TO A BLEND. Q VECTORS ARE SHOWING THE BEST AREAS FOR UPWARD MOTION AND STORM DEVELOPMENT REMAINING JUST TO OUR NORTH TOMORROW...MAINLY OVER THE UPPER GREAT LAKES REGION. SOME DECENT CONVERGENCE DOES MAKE IT INTO KY AS WELL...MOVING FROM WEST TO EAST ACROSS THE STATE. AS IT HEADS INTO EASTERN KY...EVEN THE QVECTOR CONVERGENCE PICKS UP ON A BRIEF LULL IN ACTIVITY ACROSS THE SE PORTION OF THE STATE WITH DOWNSLOPE WINDS IN PLACE. THIS QUICKLY DISAPPEARS AS THE BEST CONVERGENCE MOVES OVER THE REGION...SO FURTHER SUPPORT THAT AT SOME POINT THE MOISTURE WILL BE ENOUGH TO OVERCOME ANY EFFECTS FROM THE WIND DIRECTION. LOW LEVEL WIND SHEAR DURING THE DAY TOMORROW ISN/T QUITE AS IMPRESSIVE AS THAT EXPECTED THIS EVENING...BUT IT SEEMS TO BE A BIT DEEPER. WINDS IN THE UPPER LEVELS ARE QUITE STRONG...SO EXPECT A GOOD DRIVING FORCE AND THE POTENTIAL FOR A LINE OF SHOWERS/STORMS TO TRAVERSE KY /AS WAS REFLECTED IN THE MONDAY EVENING/MONDAY NIGHT POPS AND WEATHER/. MONDAY NIGHT/S LINE OF STORMS IS ALSO EXPECTED TO BRING THE BEST THREAT FOR HEAVY PRECIP DURING THE SHORT TERM ACCORDING TO THE LAST FEW MODEL RUNS. AFTER ROUND ONE OF PRECIP MOVES IN TONIGHT AND TOMORROW...A STRONGER SECOND LINE WILL DEVELOP CLOSER TO THE FRONT. MOISTURE GETTING PULLED IN WILL ALLOW FOR 6 HOUR QPF AMOUNTS WELL IN THE 1 TO 3 INCH RANGE BY 6Z TUESDAY...TRAVERSING EASTERN KY DURING THIS TIME. WITH THIS AMOUNT OF EXPECTED CONVECTIVE RAIN...AND THE CONTINUED POTENTIAL FOR SOME THUNDERSTORMS PRODUCING HEAVY SHOWERS OVER SMALL AREAS...THERE DOES LIE THE THREAT OF FLOODING ACROSS PORTIONS OF THE STATE...INCLUDING EASTERN KY. WINDS ALOFT ARE QUITE IMPRESSIVE AS THIS LINE MOVES OVER...SO ANY STORMS OR HEAVY RAIN SHOWERS BRING THE THREAT OF TRANSFERRING SOME OF THESE POTENTIALLY DAMAGING WINDS TO THE GROUND. AS FAR AS THE FLOODING...WILL PROBABLY NEED TO ISSUE A WATCH AT SOME POINT IN THE NEAR FUTURE. ELECTED NOT TO DURING THE DAY SHIFT JUST FOR THE SHEER FACT THAT THE MODELS ARE STILL HAVING A HARD TIME AGREEING...AND REALLY ITS GOING TO BE A MATTER OF HOW MUCH PRECIP WE END UP RECEIVING OVERNIGHT TONIGHT AND TOMORROW MORNING TO KNOW HOW SATURATED THE SOIL WILL BE LEADING INTO THE EVENING. WILL MENTION CONCERNS TO INCOMING SHIFT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 425 PM EDT SUN APR 27 2014 THE MODELS CONTINUE TO BE IN GOOD AGREEMENT ALOFT WITH THE LARGE AND LUMBERING CLOSED LOW OVER THE MID SECTION OF THE NATION AT THE START OF THE EXTENDED. THIS DOMINANT FEATURE ROLLS OVER ON ITSELF AS IT SLOWLY FILLS AND LIFTS NORTH INTO THE UPPER MIDWEST AND WESTERN GREAT LAKES BY 00Z THURSDAY. THE SYSTEM BECOMES MORE PROGRESSIVE TOWARD THE END OF THE WEEK...EVENTUALLY EXITING INTO EASTERN CANADA. BEFORE IT DOES SO...A CONTINUATION OF A SERIES OF MID LEVEL ENERGY PACKETS WILL PLOW THROUGH KENTUCKY BRINGING PERIODIC SUPPORT TO CONVECTION THROUGHOUT THE REGION. FOR TUESDAY...A KEY ONE OF THESE PACKETS MOVES OVER EAST KENTUCKY EARLY FOLLOWED BY ANOTHER LATE IN THE DAY AND INTO EARLY WEDNESDAY. THESE PACKETS DO WEAKEN WITH TIME SO THAT THE VERSION THAT GOES THROUGH ON MIDDAY WEDNESDAY WILL LIKELY NOT PACK THE PUNCH OF THE EARLIER ONES. FALLING HEIGHTS LOCALLY WILL BE NOTED INTO THURSDAY MORNING EVEN AS THE MAIN LOW TO THE NORTH WEAKENS BUT BY THIS TIME THE ENERGY SWIRLING PAST WILL BE SIMILARLY WEAKER. IT IS ALSO ABOUT THIS TIME THAT THE AGREEMENT OF THE GEM WITH THE NEARLY LOCKSTEP ECMWF AND GFS AT MID LEVELS FADES AND ITS SOLUTION IS SUBSEQUENTLY DISCOUNTED. THE OTHER MODELS CONTINUE TO MAINTAIN LOWER THAN NORMAL 500MB HEIGHTS OVER EAST KENTUCKY INTO THE WEEKEND DUE TO THE ARRIVAL OF ANOTHER...MORE PROGRESSIVE AND OPEN...TROUGH FROM THE PLAINS. THE GFS IS A BIT BETTER CONSOLIDATED WITH THIS THAN THE ECMWF AS IT TAKES ITS AXIS THROUGH EAST KENTUCKY EARLY SATURDAY WHILE THE ECMWF SNEAKS A LEAD WAVE THROUGH ON FRIDAY WITH THE REST OF THE SYSTEM PASSING THROUGH LATER SATURDAY. HEIGHTS WILL THEN TICK UP IN THE WAKE OF THIS ACTION TO CLOSE OUT THE WEEKEND ON A WELCOMED QUIETER NOTE. FOR THE FORECAST HAVE FOLLOWED A GENERAL MODEL BLEND THROUGH THE REST OF THE WORK WEEK WITH A SLIGHT PREFERENCE FOR THE LATEST ECMWF THEREAFTER. SENSIBLE WEATHER WILL FEATURE AT LEAST ONE LAST STORMY DAY AND NIGHT TO START THE EXTENDED. THE EXPECTATION IS THAT AN ONGOING CLUSTER OF STORMS WILL BE MOVING OUT OF EASTERN KENTUCKY AT 12Z TUESDAY. HOWEVER...THE NEXT SURGE OF LIFT ASSOCIATED WITH THE MID LEVEL WAVE ROLLING INTO THE AREA LATER THAT DAY WILL START TO ACT ON THE ENVIRONMENT OF EAST KENTUCKY DURING THE AFTERNOON. THIS WILL COMBINE WITH THE MOIST BOUNDARY LAYER...HEATING THROUGH THE DAY...TO GENERATE DECENT INSTABILITY LIKELY KICKING OFF ANOTHER CONVECTIVE CLUSTER. WITH THE VEERING SHEAR PROFILE AND POTENTIAL FOR HIGHER INSTABILITY BY EVENING TUESDAY...WILL CONTINUE THE THREAT OF STRONG TO SEVERE STORMS. THESE STORMS MAY LINGER INTO THE NIGHT BEFORE CLEARING OUT TO THE EAST ALONG WITH THE SYSTEM/S SLOW MOVING COLD FRONT FINALLY PUSHING OUT OF THE AREA. THE NEARBY FRONT AND LOW MID LEVEL HEIGHTS SHOULD LEAVE WEDNESDAY WITH A POTENTIAL FOR RENEWED CONVECTION...THOUGH THE THUNDER THREAT WILL PROBABLY BE LIMITED TO THE FAR EAST AND MAINLY EARLIER IN THE DAY. THE THREAT OF SHOWERS WILL THEN CONTINUE THROUGH THE REST OF THE WORK WEEK AND INTO THE FIRST PART OF THE WEEKEND WHILE LIMITED INSTABILITY AND COOLER TEMPERATURES KEEP THE THREAT OF THUNDER TO A MINIMUM. HAVE GONE WITH DRY WEATHER FOR SUNDAY AS HIGH PRESSURE SHOULD BE MOVING OVERHEAD. TEMPERATURES WILL BE DEFINITELY ON THE COOL SIDE OF NORMAL FOR THE BULK OF THE EXTENDED IN THE WAKE OF THE SYSTEM/S SLOW MOVING COLD FRONT PASSING THROUGH ON WEDNESDAY. TUESDAY REMAINS THE MOST CHALLENGING DAY FOR MAX TEMPERATURES DUE TO QUESTIONS OF CLEARING BEHIND THE DEPARTING EARLY MORNING BATCH OF CONVECTION. MORE...AND QUICKER...CLEARING WILL ALLOW TEMPERATURES TO SOAR INTO THE UPPER 70S AND ALSO SPIKE THE INSTABILITY MAKING FOR A BETTER POTENTIAL FOR SEVERE WEATHER. HOWEVER...THERE IS A POTENTIAL FOR CONVECTIVE DEBRIS AND LINGERING LOW CLOUDS/SHOWERS TO KEEP TEMPERATURES CAPPED AND INSTABILITY/SVR POTENTIAL MORE LIMITED. THE CR GRID LOAD CAME IN PRETTY GOOD FOR THE BULK OF THE EXTENDED... THOUGH DID MAKE SOME ADJUSTMENTS TOWARD THE LATEST ECMWF SOLUTION FOR THE END OF THE WORK WEEK AND INTO THE WEEKEND...PARTICULARLY FOR A DRY SUNDAY. DID ALSO FINE TUNE SOME LOW TEMP GRIDS LATER IN THE FORECAST TO ALLOW FOR SOME ENHANCED RIDGE AND VALLEY DETAIL OVER THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 146 PM EDT SUN APR 27 2014 WHILE PREDOMINATE VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF PERIOD...ESPECIALLY INTO THIS EVENING...A STRONG STORM SYSTEM APPROACHING FROM THE SW WILL BE THE MAIN DRIVER FOR BOTH THE WEATHER AND ASSOCIATED PARAMETERS OVER THE NEXT 24 HOURS. CURRENTLY...A COLD FRONT IS POSITIONED JUST WEST OF THE MISSISSIPPI RIVER VALLEY...SLOWLY CRAWLING EASTWARD AS WE HEAD THROUGH THE NEXT 24 HOURS. A LARGE AMOUNT OF INSTABILITY ACCOMPANIES THIS SYSTEM...SO ANY SHOWERS THAT DEVELOP ALSO HAVE THE POTENTIAL FOR TURNING INTO SOME DECENT THUNDERSTORM CELLS. DESPITE MOST MODEL PRECIP DATA AND ONGOING FORECAST...FORECAST SOUNDINGS ARE KEEPING AN AREA OF LOW LEVEL DRY AIR THROUGH PORTIONS OF THE TAF PERIOD...POTENTIALLY HAMPERING CONVECTION. BASED ON THE UPSTREAM CONDITIONS...HOWEVER...DO EXPECT SHOWERS AND THUNDERSTORMS TO AFFECT THE REGION BEGINNING LATE THIS EVENING...THEN CONTINUING INTO THE OVERNIGHT AND TOMORROW. THE EXACT SET UP/TIMING/ AND IMPACTS TO TAF SITES HAS YET TO BE DETERMINED. HOWEVER...SOME LOCALLY HEAVY RAINFALL...STRONG LIGHTNING...AND GUSTY WINDS ARE ALL DEFINITE THREATS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JMW LONG TERM...GREIF AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
355 PM EDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 355 PM EDT SUN APR 27 2014 STARTING INTO AN ACTIVE PERIOD DURING THE SHORT TERM. A SURFACE LOW PRESSURE SYSTEM WILL REMAIN OVER THE CENTRAL PLAINS THIS EVENING...WHILE SEVERAL WAVES OF ENERGY WILL CONTINUE TO ROTATE AROUND THIS SYSTEM. EASTERN KY WILL REMAIN IN THE WARM SECTOR...WITH A WARM FRONT POSITIONED ACROSS MUCH OF THE STATE. MEANWHILE...WESTERN AND CENTRAL KY WILL FIND THEMSELVES POSITIONED BETWEEN THE WARM FRONT AND COLD FRONT...WITH WARM UNSTABLE AIR CONTINUING TO FILTER IN AND ABUNDANT MOISTURE TO ACCOMPANY. WHILE NOT MUCH PROGRESSION IS EXPECTED THIS AFTERNOON OR TONIGHT IN TERMS OF THE SURFACE LOW AND THE ASSOCIATED FRONTS...THE INCREASED INSTABILITY DURING THE AFTERNOON WILL WORK TO HELP ANY CONVECTIVE DEVELOPMENT TO SPREAD EASTWARD SLOWLY. LATEST HIRES MODELS...INCLUDING THE NAM12/HRRR/AND ECMWF ALL POINT AT PRECIP ENTERING INTO EASTERN KY BETWEEN 0 AND 6Z AND THEN CONTINUING EASTWARD THROUGHOUT THE NIGHT. IT IS ALSO AROUND THIS POINT THAT GFS40 AND NAM12 FORECAST SOUNDINGS SHOW SOME IMPRESSIVE LOW LEVEL SHEER IN PORTIONS OF EASTERN KY. WHILE LINGERING DRY LOW LEVEL AIR AND SE DOWNSLOPE WINDS COULD WORK TO HOLD OFF SOME PRECIP IN THE EVENING...EXPECT THAT ISOLATED TO SCATTERED SHOWERS WILL DEVELOP. IN DOING SO...MOISTENING OF THE LOW LEVELS WILL BE ENOUGH TO ALLOW UNSTABLE AIR TO RISE AND THUNDERSTORMS TO DEVELOP. IN ADDITION...BASED ON STRONG STORMS THAT HAVE DEVELOPED UPSTREAM...HAVE KEPT THUNDER AS THE PREDOMINATE WX TYPE THIS EVENING AND THROUGH THE NIGHT. BETWEEN 3Z AND 12Z MONDAY...CHANCE POPS WILL OVERSPREAD THE AREA. HOWEVER...LATEST HI-RES GUIDANCE IS POINTING AT A DRY POCKET DEVELOPING AS DOWNSLOPE FLOW INCREASES SLIGHTLY ACROSS THE SOUTHEAST PORTION OF THE STATE. LATEST RUC13 OMEGA IS ALSO SUPPORTIVE OF THIS IDEA...SHOWING DOWNWARD MOTION ACROSS THE SE PORTION OF THE STATE BY 9Z. THE QUESTION THEN WILL BE...HOW MUCH WILL THIS DOWNSLOPING INHIBIT ANY STORM DEVELOPMENT? HOW FAR INTO EASTERN KY COULD IT POTENTIALLY INHIBIT STORM GROWTH AND RAIN...AND WILL WE STILL EXPECT SOME ISOLATED TO SCATTERED CHANCES...OR WILL DOWNSLOPE CUT OFF POTENTIAL ALL TOGETHER? UNFORTUNATELY...THESE ARE ALL QUESTIONS WHICH CAN/T REALLY BE ANSWERED UNTIL THE MAIN CONVECTION REACHES OUR AREA. UNTIL THEN...WILL TRY TO PLAY ON THIS THINKING...AND TREND DOWN POPS SLIGHTLY FOR THE SE PORTION OF THE CWA. DURING THE DAY TOMORROW...SURFACE LOW WILL HAVE PROGRESSED ONLY SLIGHTLY EASTWARD...THOUGH THE SURFACE COLD FRONT WILL HAVE ENTERED INTO THE MISSISSIPPI VALLEY REGION. WITH THE FORCING SO GREAT IN PROXIMITY TO THIS FRONT...AND A STRONG PULL OF GULF MOISTURE...EXPECT SHOWERS/TSRA TO OVERCOME THE DOWNSLOPING PULL. ESPECIALLY IF WINDS SHIFT MORE SOUTHERLY FOR A PERIOD OF TIME...COULD SEE MORE WIDESPREAD DEVELOPMENT ACROSS THIS AREA. UNFORTUNATELY...EVEN THE HI-RES MODELS ARE SHOWING SOME DISAGREEMENT ON THE EXTENT AND MAGNITUDE OF PRECIP FOR TOMORROW...SO HAVE TRIED TO STICK TO A BLEND. Q VECTORS ARE SHOWING THE BEST AREAS FOR UPWARD MOTION AND STORM DEVELOPMENT REMAINING JUST TO OUR NORTH TOMORROW...MAINLY OVER THE UPPER GREAT LAKES REGION. SOME DECENT CONVERGENCE DOES MAKE IT INTO KY AS WELL...MOVING FROM WEST TO EAST ACROSS THE STATE. AS IT HEADS INTO EASTERN KY...EVEN THE QVECTOR CONVERGENCE PICKS UP ON A BRIEF LULL IN ACTIVITY ACROSS THE SE PORTION OF THE STATE WITH DOWNSLOPE WINDS IN PLACE. THIS QUICKLY DISAPPEARS AS THE BEST CONVERGENCE MOVES OVER THE REGION...SO FURTHER SUPPORT THAT AT SOME POINT THE MOISTURE WILL BE ENOUGH TO OVERCOME ANY EFFECTS FROM THE WIND DIRECTION. LOW LEVEL WIND SHEAR DURING THE DAY TOMORROW ISN/T QUITE AS IMPRESSIVE AS THAT EXPECTED THIS EVENING...BUT IT SEEMS TO BE A BIT DEEPER. WINDS IN THE UPPER LEVELS ARE QUITE STRONG...SO EXPECT A GOOD DRIVING FORCE AND THE POTENTIAL FOR A LINE OF SHOWERS/STORMS TO TRAVERSE KY /AS WAS REFLECTED IN THE MONDAY EVENING/MONDAY NIGHT POPS AND WEATHER/. MONDAY NIGHT/S LINE OF STORMS IS ALSO EXPECTED TO BRING THE BEST THREAT FOR HEAVY PRECIP DURING THE SHORT TERM ACCORDING TO THE LAST FEW MODEL RUNS. AFTER ROUND ONE OF PRECIP MOVES IN TONIGHT AND TOMORROW...A STRONGER SECOND LINE WILL DEVELOP CLOSER TO THE FRONT. MOISTURE GETTING PULLED IN WILL ALLOW FOR 6 HOUR QPF AMOUNTS WELL IN THE 1 TO 3 INCH RANGE BY 6Z TUESDAY...TRAVERSING EASTERN KY DURING THIS TIME. WITH THIS AMOUNT OF EXPECTED CONVECTIVE RAIN...AND THE CONTINUED POTENTIAL FOR SOME THUNDERSTORMS PRODUCING HEAVY SHOWERS OVER SMALL AREAS...THERE DOES LIE THE THREAT OF FLOODING ACROSS PORTIONS OF THE STATE...INCLUDING EASTERN KY. WINDS ALOFT ARE QUITE IMPRESSIVE AS THIS LINE MOVES OVER...SO ANY STORMS OR HEAVY RAIN SHOWERS BRING THE THREAT OF TRANSFERRING SOME OF THESE POTENTIALLY DAMAGING WINDS TO THE GROUND. AS FAR AS THE FLOODING...WILL PROBABLY NEED TO ISSUE A WATCH AT SOME POINT IN THE NEAR FUTURE. ELECTED NOT TO DURING THE DAY SHIFT JUST FOR THE SHEER FACT THAT THE MODELS ARE STILL HAVING A HARD TIME AGREEING...AND REALLY ITS GOING TO BE A MATTER OF HOW MUCH PRECIP WE END UP RECEIVING OVERNIGHT TONIGHT AND TOMORROW MORNING TO KNOW HOW SATURATED THE SOIL WILL BE LEADING INTO THE EVENING. WILL MENTION CONCERNS TO INCOMING SHIFT. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 459 AM EDT SUN APR 27 2014 A DYNAMIC STORM SYSTEM WILL BRING THE POTENTIAL FOR SEVERE WEATHER AS WELL AS EXCESSIVE RAINFALL TO EASTERN KENTUCKY EARLY ON IN THE EXTENDED PERIOD. THE MODELS ARE IN GOOD AGREEMENT WITH THE BLOCKY LONG WAVE PATTERN TO DOMINATE ACROSS THE CONUS THROUGH THE END OF THE WORK WEEK. A PLAINS UPPER LEVEL LOW WILL SLOWLY SPIRAL ITS WAY TO THE GREAT LAKES BY THE END OF THE PERIOD...KEEPING STORMY WEATHER ACROSS MUCH OF THE MISSISSIPPI VALLEY. DETAILS CONTINUE TO BE CHALLENGING ON TIMING INDIVIDUAL ROUNDS OF ENERGY SPAWNED FROM THE LOW...SO HAVE STUCK CLOSE TO A BLEND OF THE GUIDANCE. ON MONDAY NIGHT...A FAIRLY STOUT LOW LEVEL JET WILL BE NOSING IN FROM THE TENNESSEE VALLEY IN CONJUNCTION WITH GOOD UPPER LEVEL FORCING. THIS WILL RESULT IN A LINE OF INTENSE CONVECTION TO MOVE IN ACROSS KENTUCKY DURING THE EVENING HOURS AND CONTINUE SHIFTING EAST WITH TIME. INSTABILITY CONTINUES TO BE ON THE WEAKER-SIDE...HOWEVER AN AMPLE WIND PROFILE A DEEPER FORCING MAY WIND UP OVERCOMING THE WEAKER INSTABILITY...WITH DAMAGING WINDS THE BIGGEST THREAT AND A SECONDARY THREAT OF ISOLATED EMBEDDED TORNADOES WITHIN ANY BOW STRUCTURES. IN ADDITION TO THE SEVERE THREAT...PWATS WILL BE APPROACHING 90TH PERCENTILE PLUS AND WITH THE CONVECTIVE LINE ORIENTING ITSELF NEARLY PARALLEL WITH THE LOW LEVEL JET...SOME TRAINING WILL BE A GOOD POSSIBILITY. THE QUESTION REMAINS...WHERE DOES ALL OF THIS SET UP EXACTLY. THE GFS/ECMWF AND LATEST 06Z NAM HAVE THE CONVECTIVE LINE CULMINATING OUT IN CENTRAL KY/TN AND SLOWLY MOVES EAST ACROSS OUR AREA OVERNIGHT. AS MENTIONED PREVIOUSLY...WILL HIGHLIGHT THE POTENTIAL IMPACTS IN A SPECIAL WEATHER STATEMENT. ONCE THIS FIRST WAVE MOVES OUT BY TUESDAY MORNING...AN ADDITIONAL ROUND OF ACTIVITY WILL MOVE THROUGH LATE TUESDAY AND ESPECIALLY TUESDAY NIGHT. THE LATEST GUIDANCE FROM THE STORM PREDICTION CENTER SUGGESTS THAT THE MORE ORGANIZED SEVERE THREAT WILL BE IN THE DEEP SOUTH...KEEPING KENTUCKY OUT OF THE SLIGHT RISK. INSTABILITY LOOKS TO BE MEAGER ONCE AGAIN...HOWEVER SHEAR LOOKS AMPLE...WITH MORE DIRECTIONAL SHEAR IN PARTICULAR...SUGGESTING A POTENTIAL OF MORE DISCRETE CELLS. AS SUCH...WILL STILL BE MENTIONING A SEVERE POTENTIAL HERE...BUT WITH JUST LESS UNCERTAINTY SINCE MUCH DEPENDS ON HOW THINGS PLAY OUT PRECEDING THIS PERIOD. UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE WORKWEEK...HOWEVER WITH LESS INTENSITY EACH DAY...AS WE LOSE INSTABILITY AS THE ENTIRE COLUMN COOLS OFF. HAVE STUCK CLOSE TO THE INHERITED FORECAST IDEA...KEEPING POPS MORE DIURNALLY FOCUSED EACH DAY. HIGHS WILL DROP FROM THE 70S TUESDAY AND WEDNESDAY...TO THE UPPER 50S AND LOW 60S BY FRIDAY AND SATURDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 146 PM EDT SUN APR 27 2014 WHILE PREDOMINATE VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF PERIOD...ESPECIALLY INTO THIS EVENING...A STRONG STORM SYSTEM APPROACHING FROM THE SW WILL BE THE MAIN DRIVER FOR BOTH THE WEATHER AND ASSOCIATED PARAMTERS OVER THE NEXT 24 HOURS. CURRENTLY...A COLD FRONT IS POSITIONED JUST WEST OF THE MISSISSIPPI RIVER VALLEY...SLOWLY CRAWLING EASTWARD AS WE HEAD THROUGH THE NEXT 24 HOURS. A LARGE AMOUNT OF INSTABILITY ACCOMPANIES THIS SYSTEM...SO ANY SHOWERS THAT DEVELOP ALSO HAVE THE POTENTIAL FOR TURNING INTO SOME DECENT THUNDERSTORM CELLS. DESPITE MOST MODEL PRECIP DATA AND ONGOING FORECAST...FORECAST SOUNDINGS ARE KEEPING AN AREA OF LOW LEVEL DRY AIR THROUGH PORTIONS OF THE TAF PERIOD...POTENTIALLY HAMPERING CONVECTION. BASED ON THE UPSTREAM CONDITIONS...HOWEVER...DO EXPECT SHOWERS AND THUNDERSTORMS TO AFFECT THE REGION BEGINNING LATE THIS EVENING...THEN CONTINUING INTO THE OVERNIGHT AND TOMORROW. THE EXACT SET UP/TIMING/ AND IMPACTS TO TAF SITES HAS YET TO BE DETERMINED. HOWEVER...SOME LOCALLY HEAVY RAINFALL...STRONG LIGHTNING...AND GUSTY WINDS ARE ALL DEFINATE THREATS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JMW LONG TERM...GEOGERIAN AVIATION...JMW
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
121 PM EDT Sun Apr 27 2014 ...Updated Aviation Discussion... ...Forecast Update... Issued at 905 AM EDT Sun Apr 27 2014 Have updated the grids this morning mainly to account for the expected evolution of convection this afternoon. WV imagery depicts a PV anomaly ejecting out of the main upper low. This shortwave is currently across portions of eastern TX and OK, but will quickly race northeast this afternoon. In response to this ejecting feature, isentropic ascent has led to the development of convection across AR/MS this morning. This convection will continue to push northeast through the day. The latest HRRR has the best handle of the ongoing convection, so have leaned on that for timing. This makes for a slightly faster arrival into the region than the previous forecast, getting convection into our southwest CWA by 18-19Z, and up toward the Louisville metro by about 21-23Z. Guidance still tries to develop decent instability (1000-2000 J/kg MLCAPE) out ahead of this incoming wave this afternoon, although this is likely a bit overdone given dewpoints are too high in guidance. Nonetheless, still feel there is potential for a few strong to perhaps marginally severe storms mainly along and west of I-65 given bulk shear values of 20-30 knots. Will continue to monitor the evolution upstream this morning and provide updates as needed. .SHORT TERM (Now through Monday)... Issued at 300 AM EDT Sun Apr 27 2014 Expect one last warm and partly cloudy day today before a slow moving cyclone brings several days of episodic storminess beginning late this evening. At 500mb a blocking pattern is developing across North America. This will drastically slow the progression of any individual waves across the CONUS through the middle of next week. Currently, a potent jet is wrapping around the eastern side of a deep upper trough now located over Colorado. This cyclone will deepen farther and close off as it encounters a persistent ridge that is forecast to lie right over the Lower Ohio Valley Sunday afternoon. By early Sunday, this cyclone is expected to occlude and become cutoff over western Kansas. Moisture, especially at mid-levels, will increase this afternoon and evening as southwesterly winds aloft brings in modified Gulf moisture northeast from Arkansas. Dewpoints won`t rise much at the surface until tonight as easterly surface winds will continue to advect continental air from over the Appalachians. Expect warm temperatures this afternoon ranging from the upper 70s to near 80. The first of several disturbances associated with the sprawling cyclone over the plains will arrive this evening. Forecast soundings show adequate surface-based instability developing by late afternoon and evening, especially southwest of Louisville. The GFS especially forecasts scattered to numerous showers and thunderstorms developing within the leading edge of a wholesale moisture surge. Aiding any convection may be the remnants of an old northwest to southeast orientated weak stationary front. Episodic convection may continue through much of early Monday as a robust low level jet sets up. After an expected break Monday, a second more potent round of convection is expect to develop later Monday afternoon and continue well into Tuesday morning. This second round will develop within an area of maximized moisture convergence ahead of slow moving occluded front. A potential exists for some training convection and locally excessive rainfall to areas south and east of the Ohio River. Expect mild temperatures in the lower 60s early Monday with highs Monday well into the mid to upper 70s. .LONG TERM (Monday Night through Saturday)... Issued at 300 AM EDT Sun Apr 27 2014 Still some debate about what will be ongoing at the start of the period, with the GFS initiating a new line of convection west of the region Monday afternoon and trudging it across our area Monday night. The NAM however has a stronger line just to our east with a weaker line initiating to the west and moving through Monday night. The 12Z Euro leaned closer to the GFS solution. The biggest factor will be how long precip lingers from earlier in the day Monday, keeping instability down. A look at the end of the high-res WRF-NMM and WRF-ARW indicates that both lean toward the NAM solution. Given this uncertainty, one has to go to the basics. We will have a pretty moist airmass in place. We do have plenty of deep-layered shear to generate stronger thunderstorms. Confidence thus is fairly high that we will have some thunderstorms Monday night, and they should provide heavy rain, perhaps some minor flooding in areas that receive heavy rain tonight and Monday. For Tuesday, model consensus is pretty good that we will see a longer breather in precip, as drier air works in aloft. However a rather potent PV anomaly will rotate around the base of our large scale low in the afternoon. This anomaly looks to come through at a better time of day for severe potential. However the instability looks to be stronger over the Deep South and would not be surprised to see that area keep us from getting too many severe reports in our forecast area. Agree with previous forecaster that the Lake Cumberland region looks to have the best chance for severe, but again this forecast relies on a lot of factors coming together so stay tuned! The multiple rounds of precip across the region, some heavy, could spark some flash flooding. Given how relatively dry we have been the last few weeks and the higher flash flood guidance, will hold off on issuing a watch at this point. Will be issuing a Hydrologic Outlook though, to highlight flood potential and let the next shift or two decide if a flash flood watch is needed. After the round of precip clears the area Tuesday evening, chances for severe weather go down. However we will not be able to get rid of rain chances the rest of the period as the stubborn upper low takes a while to push through the Northern U.S. The GFS has light QPF each day, but the other models are not showing as much. Will keep slight chances each night and low-end chance each day with low QPF. Temperatures will start off above normal for highs Tuesday, then turn noticeably colder as the cold upper low gets closer to our region and lowers thicknesses. Highs could get near 80 Tuesday in the breaks of the clouds. Then Wednesday they should drop to around 70 for most locations before dropping to around 60 Thursday through Saturday. && .AVIATION (18Z TAF Update)... Issued at 119 PM EDT Sun Apr 27 2014 A rather complex TAF period is in store as multiple rounds of convection look to affect TAF sites, along with a marginal LLWS setup tonight. Current radar imagery shows scattered storms developing across portions of TN and western KY. These storms will continue to develop northeast through the afternoon hours. Confidence in storm coverage is highest at KBWG, with decreasing confidence at KSDF and KLEX. Any terminal that does get a storm could see briefly reduced cigs/vsbys, perhaps to IFR in the heavier precipitation. Otherwise, storms should diminish a bit in coverage late this evening as the first wave pushes northeast. A low-level jet will ramp up to the west and slide into the Ohio Valley overnight, helping to bring renewed showers and thunderstorms into the region. This low-level jet will produce a marginal LLWS setup, but think surface winds will likely stay up a bit (perhaps even more than currently forecasted), which should limit impacts. Again, cigs/vsbys will likely drop in the heavier convection. Precipitation will again diminish by mid-morning Monday, setting the stage for another round of convection to develop in the afternoon, possibly affecting KSDF during the planning period. Winds on Monday will be considerably stronger than today, with sustained southerly winds at 13-18 knots, with gusts of 20-25 knots. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....JSD Long Term......RJS Aviation.......KJD
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
907 AM EDT Sun Apr 27 2014 ...Forecast Update... Issued at 905 AM EDT Sun Apr 27 2014 Have updated the grids this morning mainly to account for the expected evolution of convection this afternoon. WV imagery depicts a PV anomaly ejecting out of the main upper low. This shortwave is currently across portions of eastern TX and OK, but will quickly race northeast this afternoon. In response to this ejecting feature, isentropic ascent has led to the development of convection across AR/MS this morning. This convection will continue to push northeast through the day. The latest HRRR has the best handle of the ongoing convection, so have leaned on that for timing. This makes for a slightly faster arrival into the region than the previous forecast, getting convection into our southwest CWA by 18-19Z, and up toward the Louisville metro by about 21-23Z. Guidance still tries to develop decent instability (1000-2000 J/kg MLCAPE) out ahead of this incoming wave this afternoon, although this is likely a bit overdone given dewpoints are too high in guidance. Nonetheless, still feel there is potential for a few strong to perhaps marginally severe storms mainly along and west of I-65 given bulk shear values of 20-30 knots. Will continue to monitor the evolution upstream this morning and provide updates as needed. .SHORT TERM (Now through Monday)... Issued at 300 AM EDT Sun Apr 27 2014 Expect one last warm and partly cloudy day today before a slow moving cyclone brings several days of episodic storminess beginning late this evening. At 500mb a blocking pattern is developing across North America. This will drastically slow the progression of any individual waves across the CONUS through the middle of next week. Currently, a potent jet is wrapping around the eastern side of a deep upper trough now located over Colorado. This cyclone will deepen farther and close off as it encounters a persistent ridge that is forecast to lie right over the Lower Ohio Valley Sunday afternoon. By early Sunday, this cyclone is expected to occlude and become cutoff over western Kansas. Moisture, especially at mid-levels, will increase this afternoon and evening as southwesterly winds aloft brings in modified Gulf moisture northeast from Arkansas. Dewpoints won`t rise much at the surface until tonight as easterly surface winds will continue to advect continental air from over the Appalachians. Expect warm temperatures this afternoon ranging from the upper 70s to near 80. The first of several disturbances associated with the sprawling cyclone over the plains will arrive this evening. Forecast soundings show adequate surface-based instability developing by late afternoon and evening, especially southwest of Louisville. The GFS especially forecasts scattered to numerous showers and thunderstorms developing within the leading edge of a wholesale moisture surge. Aiding any convection may be the remnants of an old northwest to southeast orientated weak stationary front. Episodic convection may continue through much of early Monday as a robust low level jet sets up. After an expected break Monday, a second more potent round of convection is expect to develop later Monday afternoon and continue well into Tuesday morning. This second round will develop within an area of maximized moisture convergence ahead of slow moving occluded front. A potential exists for some training convection and locally excessive rainfall to areas south and east of the Ohio River. Expect mild temperatures in the lower 60s early Monday with highs Monday well into the mid to upper 70s. .LONG TERM (Monday Night through Saturday)... Issued at 300 AM EDT Sun Apr 27 2014 Still some debate about what will be ongoing at the start of the period, with the GFS initiating a new line of convection west of the region Monday afternoon and trudging it across our area Monday night. The NAM however has a stronger line just to our east with a weaker line initiating to the west and moving through Monday night. The 12Z Euro leaned closer to the GFS solution. The biggest factor will be how long precip lingers from earlier in the day Monday, keeping instability down. A look at the end of the high-res WRF-NMM and WRF-ARW indicates that both lean toward the NAM solution. Given this uncertainty, one has to go to the basics. We will have a pretty moist airmass in place. We do have plenty of deep-layered shear to generate stronger thunderstorms. Confidence thus is fairly high that we will have some thunderstorms Monday night, and they should provide heavy rain, perhaps some minor flooding in areas that receive heavy rain tonight and Monday. For Tuesday, model consensus is pretty good that we will see a longer breather in precip, as drier air works in aloft. However a rather potent PV anomaly will rotate around the base of our large scale low in the afternoon. This anomaly looks to come through at a better time of day for severe potential. However the instability looks to be stronger over the Deep South and would not be surprised to see that area keep us from getting too many severe reports in our forecast area. Agree with previous forecaster that the Lake Cumberland region looks to have the best chance for severe, but again this forecast relies on a lot of factors coming together so stay tuned! The multiple rounds of precip across the region, some heavy, could spark some flash flooding. Given how relatively dry we have been the last few weeks and the higher flash flood guidance, will hold off on issuing a watch at this point. Will be issuing a Hydrologic Outlook though, to highlight flood potential and let the next shift or two decide if a flash flood watch is needed. After the round of precip clears the area Tuesday evening, chances for severe weather go down. However we will not be able to get rid of rain chances the rest of the period as the stubborn upper low takes a while to push through the Northern U.S. The GFS has light QPF each day, but the other models are not showing as much. Will keep slight chances each night and low-end chance each day with low QPF. Temperatures will start off above normal for highs Tuesday, then turn noticeably colder as the cold upper low gets closer to our region and lowers thicknesses. Highs could get near 80 Tuesday in the breaks of the clouds. Then Wednesday they should drop to around 70 for most locations before dropping to around 60 Thursday through Saturday. && .AVIATION (12Z TAF Update)... Issued at 640 AM EDT Sun Apr 27 2014 Cirrus, and eventually some mid-level clouds will thicken today as increasing moisture streams northeast and overruns a weak stationary front. Instability will increase late this afternoon and evening. Scattered to numerous thunderstorms will develop at our TAF sites between 00 and 06z this evening, and will likely continue through 12z Monday morning. Although this convection will be episodic, think that at some point convection will affect each of our TAFs. Light winds early this morning will become east southeasterly by this afternoon and average around 7 to 10kt. Southeasterly winds will continue overnight into Monday morning at this same speed. Despite lowering ceilings, our easterly winds will keep away low strato-cu and VFR ceilings are expected up until any convection affect a terminal. MVFR ceilings and visibilities will develop in any thunderstorms. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....JSD Long Term......RJS Aviation.......JSD
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
436 PM CDT SUN APR 27 2014 .DISCUSSION... LATEST WATER VAPOR SATELLITE IMAGERY SHOWED A VIGOROUS UPPER LOW OVER NW KS/SW NE...WITH A VIGOROUS PACIFIC JET NOSING IN FROM THE PAC NW AND CURLING CYCLONICALLY THROUGH THE BASE OF THE LOW. A SUBTROPICAL JET WAS NOTED TO THE SOUTH ACROSS CENTRAL MX INTO THE WRN GULF. KLCH AND KPOE VWPS CONTINUE TO SHOW A 50KT PLUS SOUTHWESTERLY LLJ. AT THE SFC...LOW PRESSURE IS HARD TO MISS OVER NW KS...WITH A TRAILING CDFNT/DRYLINE THROUGH CENTRAL OK/TX. HARD TO HAVE A GREAT DEAL OF FAITH IN ANY SPECIFIC SHORT TERM GUIDANCE...AS PRECIOUS FEW CAUGHT THE ISOLATED TO SCATTERED ELEVATED CONVECTION THAT DEVELOPED THIS AFTERNOON. THE ONLINE SPC 4KM WRF WASNT TOO BAD...AND THE HRRR DID FINALLY CATCH ON. THESE TWO MODELS...WITH SOME ADDITIONAL SUPPORT FROM GLOBAL MODELS...DEPICT A BAND OF CONVECTION INITIATING AFTER MIDNIGHT IN THE VICINITY OF EAST CENTRAL TEXAS NE TWD SHREVEPORT. THE SOUTHWESTWARD EXTENT OF ANY SUCH DEVELOPMENT IS A BIT UNCERTAIN...BUT IT IS NOT OUT OF THE QUESTION FOR NORTHERN ZONES TO BE AFFECTED GIVEN THE THE PROJECTED EAST/NORTHEAST MOVEMENT. WILL MAINTAIN HIGHEST POPS TONIGHT IN THIS AREA...AND HOLD ONTO THE SEVERE WORDING. GENERALLY PRESERVED THE INHERITED INLAND WIND HAZARDS...BUT DID TWEAK THE MARINE HAZARDS A BIT...EASING OUT OF THE SCA FOR THE COASTAL LAKES AND BAYS MID EVENING...AND THE INLAND WATERS WEST OF CAMERON AFTER MIDNIGHT CONCURRENT WITH LATEST PROGS THAT SHOW WINDS STARTING TO DECREASE FROM WEST TO EAST OVERNIGHT AND INTO TOMORROW. A WIND ADVISORY MAY STILL BE WARRANTED FOR A TIME ACROSS SOUTH/EAST CENTRAL LOUISIANA...BUT WILL LET THE OVERNIGHT CREW MAKE THE CALL ON THAT AS IT LOOKS A LITTLE MORE MARGINAL. CONVECTIVE PROSPECTS WILL ALSO SHIFT EAST TOMORROW...AS THE CDFNT PUSHES JUST EAST OF A KSHV TO KLFK LINE BY TOMORROW AFTERNOON. HAVE GENERALLY LEFT THIS PART OF THE FORECAST AS IS...STAYING MAINLY WITH LOW TO MID RANGE POPS AND PRESERVING THE SEVERE WORDING PER SPC DAY 2 CONVECTIVE OUTLOOK. THE FRONT IS STILL FCST TO PUSH THROUGH THE DURING THE AFTERNOON AND EVENING HOURS ON TUE...WITH THE SEVERE RISK DISPLACED TO OUR EAST BY THIS TIME. ALTHOUGH STILL NOT IN IDEAL AGREEMENT...THE GFS HAS COME A LONG WAY TOWARD THE ECMWF SOLUTION IN DEPICTING SOUTHWESTERLY FLOW ALOFT...WITH ONE OR MORE FRONTAL WAVES/LOWS DEVELOPING ALONG THE FRONT. APPEARS THAT THE BEST CHANCE OF ANY RAIN AFFECTING THE AREA WOULD BE THU NIGHT-FRI...AS BOTH MODELS DEPICTING A SHORTWAVE TROF PIVOTING THROUGH THE NW GULF COAST REGION. && .MARINE... GUSTY SOUTH WINDS AND ROUGH SEAS WILL CONTINUE THIS EVENING AS A LOW PRESSURE SYSTEM DEVELOPS IN THE PLAINS. WINDS WILL BEGIN TO DIMINISH A BIT OVER THE COASTAL LAKES AND BAYS TONIGHT AND THE WATERS WEST OF CAMERON LATE TONIGHT INTO TOMORROW. TIDES WILL BE RUNNING ABOUT ONE FOOT ABOVE NORMAL TODAY AND MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE INTO EARLY NEXT WEEK AS THIS LOW PRESSURE SYSTEM SLOWLY MOVES EAST THROUGH THE CENTRAL UNTIED STATES...CULMINATING IN A FRONT CROSSING THE REGION TUESDAY NIGHT. OFFSHORE FLOW WILL PREVAIL IN THE WAKE OF THE FRONT FOR THE REST OF THE WORK WEEK. && .PRELIMINARY POINT TEMPS/POPS... KLCH 72 84 70 85 / 20 30 20 20 KBPT 72 84 69 85 / 20 20 20 20 KAEX 71 85 67 83 / 50 50 30 30 KLFT 72 84 71 85 / 30 40 40 30 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR ACADIA-CALCASIEU- EAST CAMERON-IBERIA-JEFFERSON DAVIS-LAFAYETTE-LOWER ST. MARTIN-ST. MARY-UPPER ST. MARTIN-VERMILION-WEST CAMERON. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR ALLEN-AVOYELLES- BEAUREGARD-EVANGELINE-RAPIDES-ST. LANDRY-VERNON. TX...WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR JEFFERSON-ORANGE. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR HARDIN-NORTHERN JASPER-NORTHERN NEWTON-SOUTHERN JASPER-SOUTHERN NEWTON- TYLER. GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT MONDAY FOR COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM-WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20 TO 60 NM-WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20 TO 60 NM-WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR CALCASIEU LAKE-SABINE LAKE-VERMILION BAY. SMALL CRAFT EXERCISE CAUTION FROM 9 PM THIS EVENING TO MIDNIGHT CDT TONIGHT FOR CALCASIEU LAKE-SABINE LAKE. SMALL CRAFT EXERCISE CAUTION FROM 9 PM CDT THIS EVENING THROUGH MONDAY MORNING FOR VERMILION BAY. SMALL CRAFT ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM-COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM. SMALL CRAFT EXERCISE CAUTION FROM MIDNIGHT CDT TONIGHT THROUGH MONDAY MORNING FOR COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM-COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM. && $$ 13
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
316 PM CDT SUN APR 27 2014 .SYNOPSIS... SURFACE LOW OVER WESTERN KANSAS EARLY THIS AFTERNOON WITH A DRYLINE MOVING INTO THE DALLAS-FORT WORTH AREA. SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI WELL ENTRENCHED IN THE WARM SECTOR. MORNING SOUNDINGS...AND FORECAST AFTERNOON SOUNDINGS SHOW THE AIRMASS IS CAPPED ACROSS THE AREA BELOW 800 MB. A FEW SPOTS OF CONVECTION SHOWING UP OVER SOUTHWEST LOUISIANA...BUT NOTHING ORGANIZED AT THIS TIME. BREEZY CONDITIONS ACROSS THE AREA THIS AFTERNOON WITH A FAIRLY TIGHT PRESSURE GRADIENT ALLOWING GUSTS TO 25 TO 30 MPH. TEMPERATURES ARE WELL INTO THE 80S WITH DEW POINTS MID 60S NORTH TO LOWER 70S SOUTH. && .SHORT TERM... MESOSCALE...INCLUDING HRRR AND 3KM WRF...AND SYNOPTIC SCALE MODELS SHOW VERY LITTLE IF ANY CONVECTION ACROSS THE AREA TONIGHT. THE FACT THAT THERE IS ONGOING CONVECTION OCCURRING IN SW LOUISIANA MERITS THE MENTION OF AT LEAST SMALL POPS TONIGHT...WITH BEST CHANCES NORTH. MESOSCALE 9KM WRF SHOWS LITTLE IN THE WAY OF PRECIPITATION IN OUR AREA PRIOR TO ABOUT 06Z TUESDAY. SYNOPTIC SCALE MODEL SOUNDINGS DO SHOW SOME POTENTIAL FOR THE CAP TO BREAK LATE MONDAY AFTERNOON...BUT MORE LIKELY TO OCCUR AS FRONT APPROACHES OVERNIGHT MONDAY NIGHT INTO TUESDAY MORNING. PLENTY OF INSTABILITY ABOVE THE CAP WITH MID LEVEL LAPSE RATES IN THE 700-500MB LAYER 7-8C/KM...CAPES IN 2000-3000 RANGE. BEST WIND FIELDS WILL BE NORTH OF OUR AREA...BUT DEFINITELY CANNOT RULE OUT SEVERE POTENTIAL WITH ALL MODES OF SEVERE WEATHER STILL POSSIBLE. BEST THREAT WILL BE FROM INTERSTATE 12 NORTHWARD LATE MONDAY NIGHT INTO MIDDAY TUESDAY. PLAN IS TO GO WELL ABOVE MAV POPS FOR MONDAY THROUGH TUESDAY...PAYING SOME HEED TO THE CONSIDERABLY HIGHER PRECIPITATION COVERAGE DEPICTED BY THE ECMWF SOLUTION. MET GUIDANCE ALSO SUPPORTS THIS TO SOME EXTENT...ALTHOUGH EVEN THOSE POPS LOOK A LITTLE LOW FOR MONDAY NIGHT. PRECIPITABLE WATER VALUES NEAR OR ABOVE 1.50 INCHES...SO HEAVY RAIN IS POSSIBLE WITH THESE STORMS. AT THIS POINT...FLASH FLOOD GUIDANCE IS RATHER HIGH...SO WE SHOULD BE ABLE TO HANDLE THE 2 INCHES OR SO THAT THESE STORMS MAY PRODUCE. MAIN PUSH OF DRIER AIR SHOULD MOVE MAIN CONVECTIVE THREAT EAST OF THE AREA BY LATE TUESDAY AFTERNOON. ALL SYNOPTIC SCALE MODELS HAVE COLD FRONT COMPLETELY EAST OF THE AREA BY WEDNESDAY MORNING...BUT STILL CLOSE ENOUGH THAT IT IS NOT CERTAIN THAT POST FRONTAL PRECIPITATION WILL HAVE CLEARED THE AREA. 35 && .LONG TERM... FRONTAL SYSTEM ONLY PROGRESSES SLOWLY EASTWARD WEDNESDAY...WITH RAIN CHANCES REMAINING ACROSS EASTERN SECTIONS AND POSSIBLY THE COASTAL WATERS. BOTH GFS AND ECMWF TAKE A NORTHERN STREAM SHORTWAVE ACROSS THE AREA ON FRIDAY...BUT ECMWF IS MUCH MORE AGGRESSIVE WITH RAIN CHANCES AS IT DEVELOPS A STRONGER SURFACE LOW ALONG THE MIDWEEK FRONT. FOR NOW...HAVE NOT MADE MAJOR CHANGES TO RAIN CHANCES AT THE END OF THE WEEK...BUT WILL NEED TO CONSIDER BUMPING THEM UP IN LATER FORECASTS. EXPECT TEMPERATURES ABOUT 10 DEGREES BELOW NORMAL BEHIND THE MIDWEEK FRONT...MODERATING SOMEWHAT BY WEEKS END. 35 && .AVIATION... GENERALLY MVFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD WITH A BRIEF PERIOD OF IFR CIGS POSSIBLE LATE TONIGHT. GUSTY SOUTH WINDS WILL CAM A BIT AFTER SUNSET BUT WILL REMAIN SUSTAINED IN THE 10 TO 15 KT RANGE OVERNIGHT. EXPECT WINDS TO STRENGTHEN AGAIN AFTER SUNRISE WITH SUSTAINED WINDS OF 15 TO 20 KTS AND GUSTS 20 TO 30 KTS DURING THE DAY MONDAY. BEST CHANCE OF THUNDERSTORMS APPEARS TO BE AFTER 18Z MONDAY...SO THERE IS CURRENTLY NO MENTION OF CONVECTION IN THE TAFS. && .MARINE... SOUTHERLY WINDS WILL INCREASE IN ADVANCE OF A SLOW MOVING LOW PRESSURE SYSTEM MOVING OUT OF THE ROCKIES INTO THE CENTRAL PLAINS THROUGH TUESDAY. WINDS SHOULD RAMP UP ENOUGH TO WARRANT A SMALL CRAFT ADVISORY TONIGHT. WINDS WILL REMAIN ELEVATED THROUGH TUESDAY UNTIL THE FRONT PUSHES THROUGH THE AREA...SO LOOK FOR EXTENSIONS AND CHANGES IN THE SMALL CRAFT CONDITIONS OVER THE NEXT 2 DAYS. THE COLD FRONT WILL MOVE INTO THE REGION AND SLOW DOWN AS IT PUSHES THROUGH TUESDAY NIGHT AND EARLY WEDNESDAY. SHOWERS AND THUNDERSTORMS...SOME STRONG WILL IMPACT THE COASTAL WATERS MONDAY NIGHT THROUGH EARLY WEDNESDAY. THE FRONT WILL GET A STRONGER PUSH OFFSHORE WEDNESDAY NIGHT INTO THURSDAY AS COOLER AIR AND HIGH PRESSURE BUILD OUT OF THE ROCKIES AND PLAINS INTO THE NORTH GULF OF MEXICO. THIS WILL LIKELY CAUSE NORTHWEST WINDS TO BECOME A BIT BREEZY OVER THE COASTAL WATERS WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. && .DECISION SUPPORT... DSS CODE...BLUE. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...SLURRY SUPPORT MONITORING RIVER FLOODING MONITORING SEVERE WEATHER THREAT FOR MONDAY/TUESDAY DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE && .PRELIMINARY POINT TEMPS/POPS... MCB 69 82 69 82 / 20 50 60 40 BTR 71 87 71 87 / 20 40 60 40 ASD 70 84 70 83 / 20 30 60 60 MSY 72 84 72 84 / 20 30 60 50 GPT 73 81 72 81 / 20 30 70 60 PQL 69 81 69 80 / 20 20 60 60 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...SMALL CRAFT ADVISORY FROM 10 PM SUNDAY TO 1 PM MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM. MS...NONE. GM...SMALL CRAFT ADVISORY FROM 10 PM SUNDAY TO 1 PM MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM. && $$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
726 PM EDT MON APR 28 2014 .SYNOPSIS... HIGH PRESSURE WILL BUILD SOUTH ACROSS THE REGION TONIGHT THROUGH WEDNESDAY...THEN MOVE EAST WEDNESDAY NIGHT. LOW PRESSURE WILL MOVE EAST ACROSS THE REGION THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... 720 PM UPDATE: ADJUSTED THE SKY CONDITIONS TO HOLD ONTO MORE CLOUDS ACROSS THE NORTHERN CWA THROUGH EARLY TUESDAY MORNING. THEREFORE, THIS WILL KEEP THE OVERNIGHT TEMPERATURES UP A BIT. THE LATEST HRRR AND GFS INDICATE SHOWERS WEAKENING W/THE LOSS OF SUBSTANTIAL FORCING IN THE MID LEVELS. THEREFORE, SHIFTED THE AXIS OF SHOWERS TO THE WESTERN AREAS OVERNIGHT W/PRECIP CHANCES DROPPING BELOW 10% ACROSS THE EASTERN 1/2 OF THE CWA. PREVIOUS DISCUSSION... SURFACE/UPPER LEVEL LOW PRESSURE LOCATED SOUTHEAST OF NOVA SCOTIA WILL SLOWLY MOVE EAST TONIGHT. HOWEVER...CLOUDS AROUND THE LOWS WILL CONTINUE TO WRAP BACK ACROSS THE REGION FROM THE MARITIMES EARLY TONIGHT. COULD ALSO STILL HAVE AN ISOLATED SHOWER EARLY TONIGHT. HIGH PRESSURE WILL THEN BUILD SOUTH ACROSS THE REGION OVERNIGHT THROUGH TUESDAY. CLOUD COVER WILL DECREASE ACROSS THE REGION OVERNIGHT WITH BUILDING HIGH PRESSURE. PARTLY/MOSTLY SUNNY SKIES ARE THEN EXPECTED ACROSS THE FORECAST AREA TUESDAY. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 20S TO AROUND 30 NORTH...TO THE LOWER TO MID 30S DOWNEAST. HIGH TEMPERATURES TUESDAY WILL RANGE FROM AROUND 50 TO THE LOWER 50S NORTH...TO THE LOWER TO MID 50S DOWNEAST. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... HIGH PRESSURE WILL CREST OVER THE REGION TUESDAY NIGHT ALLOWING FOR SKIES TO BE MAINLY CLEAR TO PARTLY CLOUDY. THIS WILL SET UP FAIRLY GOOD CONDITIONS FOR RADIATIONAL COOLING SO WITH THIS FORECAST LOWERED THE OVERNIGHT LOWS BY A COUPLE DEGREES OVER EASTERN AREAS WHERE SKIES WILL BE CLEAR WITH NEAR CALM WINDS RIGHT UNDER THE RIDGE AXIS. EXPECT LOWS GENERALLY IN THE 20S TO LOW 30S ACROSS THE CWA...COLDEST EAST AND NORTH. FOR WEDNESDAY, SOME MID AND HIGH LEVEL CLOUDINESS WILL START TO ADVANCE INTO THE AREA BUT OTHERWISE EXPECT FAIR WEATHER WITH HIGHS GENERALLY IN THE 50S EXCEPT RIGHT AROUND 50 ALONG THE COAST WHERE AN ONSHORE WIND WILL KEEP TEMPS A BIT COOLER. THE NEXT SYSTEM IN ASSOCIATION WITH AN UPPER LEVEL LOW ADVANCES INTO THE AREA FOR FOR WEDNESDAY NIGHT INTO THURSDAY BRINGING MORE RAIN. OVERALL, MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH THIS SYSTEM ALTHOUGH THE GEM GLOBAL BRINGS IN PRECIPITATION A BIT FASTER WITH THE GFS THE SLOWEST AND THE ECMWF RIGHT IN THE MIDDLE. TRENDED TOWARD THIS MIDDLE SOLUTION IN TERMS OF TIMING THE ONSET OF PRECIPITATION AND EXPECT RAIN TO GRADUALLY BEGIN MOVING IN FROM WEST TO EAST AROUND OR SHORTLY AFTER MIDNIGHT AND REACH EASTERN AREAS THURSDAY MORNING. RAIN LOOKS TO THEN CONTINUE THROUGH A GOOD PORTION OF THE DAY. UTILIZED A BLEND OF THE ECMWF/GEM/GFS FOR QPF AMOUNTS WITH INDICATIONS AT THIS POINT FOR MOST AREAS TO SEE A HALF TO THREE QUARTERS OF AN INCH OF RAIN BY LATE THURSDAY. THE RAIN WILL KEEP TEMPERATURES COOL FOR THURSDAY WITH HIGHS IN THE MID TO UPPER 40S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... A BLOCKING PATTERN FAVORING GENERALLY HIGHER THAN NORMAL HEIGHTS IN NORTHERN PORTIONS OF EASTERN CANADA AND LOWER THAN NORMAL HEIGHTS ACROSS THE NORTHERN US WILL TAKE US THROUGH THE FIRST WEEK OF MAY. THIS WILL KEEP THE PATTERN GENERALLY UNSETTLED AS A TROUGH OF LOW PRESSURE STALLS OVER THE GREAT LAKES INTO THIS WEEKEND WHILE WEAK SHORTWAVES RIPPLE EAST OUT OF THIS TROUGH. THIS PATTERN FAVORS LOTS OF CLOUDS AND MOISTURE WITH SLIGHTLY COOLER THAN NORMAL TEMPERATURES. SOME BREAKS IN THE OVERCAST, HOWEVER, ARE LIKELY FROM TIME TO TIME. AN OCCLUSION WILL BE LIFTING TO OUR NORTHEAST THURSDAY NIGHT WITH SOME SHOWERS LIKELY ACROSS THE NORTH. FRIDAY WILL BE PARTLY TO MOSTLY CLOUDY AS THIS OCCLUSION CONTINUES AWAY TO OUR NORTHEAST. ANOTHER WEAK SHORTWAVE TROUGH WILL MOVE THROUGH ON SATURDAY. THE NORTH WILL LIKELY BE MOSTLY CLOUDY WITH SOME SHOWERS WHILE DOWNEAST STAYS CLOUDY TO PARTLY SUNNY. A THIRD RIPPLE OF LOW PRESSURE PROGRESSING THROUGH ON SUNDAY WILL BRING A CONTINUATION OF CLOUDY TO PARTLY SUNNY SKIES WITH SPOTTY SHOWERS POSSIBLE ACROSS THE AREA. THE UPPER TROUGH OVER THE GREAT LAKES WILL FINALLY MOVE EAST ON MONDAY POSSIBLY CAUSING A PERIOD OF STEADIER RAIN. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... NEAR TERM: OCCASIONAL MVFR CONDITIONS...MOSTLY CEILINGS...WILL OCCUR ACROSS THE REGION EARLY TONIGHT. VFR CONDITIONS WILL THEN DEVELOP OVERNIGHT. VFR CONDITIONS ARE EXPECTED ACROSS THE REGION TUESDAY. SHORT TERM: VFR CONDITIONS WILL PREVAIL TUESDAY NIGHT THROUGH WEDNESDAY BEFORE LOWERING TO MVFR AND EVENTUALLY IFR OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY. OCCASIONAL MVFR CONDITIONS ARE POSSIBLE FRIDAY INTO SATURDAY. && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT STARTING THIS EVENING THEN RUNNING THROUGH TUESDAY FOR MUCH OF THE WATERS...WITH THE EXCEPTION OF THE INTRACOASTAL WATERS. CONDITIONS ON THE INTRACOASTAL WATERS WILL APPROACH SMALL CRAFT ADVISORY LEVELS AND MIGHT NEED TO BE INCLUDED IN THE ADVISORY LATER TONIGHT OR TUESDAY. SHORT TERM: WINDS AND SEAS WILL DIMINISH THROUGH TUESDAY NIGHT. WEDNESDAY WILL FEATURE A BRIEF RESPITE BEFORE WINDS/SEAS COME UP AGAIN LATER WEDNESDAY NIGHT INTO THURSDAY AHEAD OF AN APPROACHING LOW WHICH WILL ALSO BRING RAIN AND FOG. INDICATIONS ARE FOR CONDITIONS TO REACH SCA LEVELS ONCE AGAIN BY THURSDAY AFTERNOON. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR ANZ050-051. && $$ NEAR TERM...HEWITT/NORCROSS SHORT TERM...FITZSIMMONS LONG TERM...BLOOMER AVIATION...HEWITT/NORCROSS/FITZSIMMONS MARINE...HEWITT/NORCROSS/FITZSIMMONS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
645 PM EDT SUN APR 27 2014 .SYNOPSIS... LOW PRESSURE SOUTH OF NOVA SCOTIA WILL CONTINUE MOVING INTO THE OPEN ATLANTIC TONIGHT INTO MONDAY. HIGH PRESSURE WILL BUILD SOUTH ACROSS THE REGION MONDAY NIGHT THROUGH WEDNESDAY. && .NEAR TERM /THROUGH MONDAY/... 645 PM UPDATE...SHOWERS CONTINUE TO PUSH TO THE WEST/SOUTHWEST AROUND LOW PRES EAST OF NOVA SCOTIA. THE SHOWERS HAVE BEEN FALLING APART TO SOME DEGREE AS THEY MOVE INTO EASTERN MAINE WHERE THE LOW LEVELS ARE SOMEWHAT DRY. THE BEST CHANCE FOR A FEW SHOWERS THROUGH THE EVENING WILL BE ACROSS THE EASTERN HALF OF THE CWA. ONLY MINOR TWEAKS TO THE ONGOING FORECAST BASED ON THE LATEST OBSERVATIONS AND RECENT RADAR TRENDS. PREVIOUS DISCUSSION... THE CHALLENGE WILL DEFINITELY BE THE TEMPERATURES AND WHERE TO PLACE RAINFALL CHANCES. LOW PRES WAS SPINNING SE OF NOVA SCOTIA PER THE 18Z ANALYSIS. SFC TROUGH EXTENDING OFF THIS LOW EXTENDED BACK EASTERN AND CENTRAL MAINE. THE FIRST BATCH OF LIGHT RAIN/SHOWERS MOVED SSW EARLY TODAY AND ANOTHER ROUND IS APPROACHING FROM NEW BRUNSWICK. THE RAIN HAS BEEN WEAKENING AS IT RUNS INTO DRIER AIR AS SEEN BY THE LATEST SATELLITE VISIBLE IMAGERY SHOWING BREAKS IN THE CLOUDS. BEST SUPPORT FOR SUBSTANTIAL RAIN HAS BEEN OVER THE EASTERN SECTIONS OF WASHINGTON COUNTY. DECENT LLVL CONVERGENCE AND MID LEVEL FORCING IS THERE AS SEEN BY BOTH THE RAP AND NAM12. EXPECTING THIS TREND TO CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON. CARRIED CHANCE POPS(30-50%) FOR THE CWA TONIGHT W/THE HIGHEST CHANCES ACROSS NORTHERN AND EASTERN SECTIONS. AS ONE TRAVELS FURTHER W AND SW, SHOWERS WILL WEAKEN DUE TO SUBSIDENCE IN PLACE. CLOUDS WILL HANG AROUND THROUGHOUT THE NIGHT AND THIS WILL KEEP TEMPERATURES WELL ABOVE 32F WHICH SHOULD ALLOW FOR ALL LIQUID PRECIP. RAINFALL AMOUNTS HAVE BEEN LIGHT AND SEE NO SUPPORT FOR THIS TO CHANGE MUCH OVER THE NEXT 24 HRS. THEREFORE, STAYED W/QPF OF 0.10" OR LESS THROUGH MONDAY. CONDITIONS LOOK TO IMPROVE THROUGHOUT THE DAY ON MONDAY AS HIGH PRES IS FORECAST TO WEDGE DOWN FROM CANADA. SOME SUNSHINE IS EXPECTED BY MONDAY AFTERNOON ESPECIALLY ACROSS THE NORTHERN AND EASTERN SECTIONS WHILE THE CENTRAL HIGHLANDS WILL HANG ON TO MORE CLOUDS. THIS WILL LEAD TO A VARIATION IN TEMPERATURES. DECIDED TO BOOST DAYTIME HIGHS ON MONDAY UP TO READINGS AOA 50F MAINLY FOR THE NORTHERN AND EASTERN SECTIONS. CENTRAL AND WESTERN AREAS WILL HANG W/MORE CLOUDS THUS KEEPING TEMPERATURES DOWN INTO THE 40S SOMEWHAT SIMILAR TO TODAY. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... HIGH PRESSURE WILL RIDGE SOUTH ACROSS THE REGION MONDAY NIGHT THROUGH EARLY WEDNESDAY...THEN BEGIN TO MOVE EAST LATER WEDNESDAY. CLOUD COVER WILL DECREASE ACROSS THE REGION MONDAY NIGHT. MOSTLY CLEAR SKIES WILL OCCUR ACROSS THE REGION TUESDAY INTO EARLY WEDNESDAY. CLOUD COVER WILL THEN BEGIN TO INCREASE LATER WEDNESDAY...PARTICULARLY ACROSS WESTERN PORTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE AT NEAR NORMAL...TO SLIGHTLY BELOW NORMAL...LEVELS TUESDAY/WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AN UNSETTLED PATTERN WILL TAKE HOLD ONCE AGAIN FOR THE LONG RANGE AS THE RIDGE BREAKS DOWN AND THE NEXT UPPER LEVEL LOW ADVANCES TOWARD THE REGION. CLOUDS WILL INCREASE WEDNESDAY NIGHT WITH RAIN AND SHOWERS DEVELOPING WEST TO EAST FOR THURSDAY AS AN OCCLUSION MOVES THROUGH AHEAD OF A SURFACE LOW ADVANCING NORTH ALONG THE COAST. STEADIER RAIN LOOKS TO TAPER OFF THURSDAY NIGHT WITH RAIN AMOUNTS OF A HALF INCH TO AN INCH POSSIBLE BY THIS TIME. EXPECT SHOWERS TO LINGER INTO FRIDAY IN ASSOCIATION WITH THE BROAD UPPER LEVEL LOW SITUATED OVER THE GREAT LAKES BY THIS TIME AND A LINGERING SURFACE TROUGH. SOME UNCERTAINTY DEVELOPS IN THE FORECAST FOR THE BEGINNING OF NEXT WEEKEND. OVERALL, THE UNSETTLED PATTERN REMAINS HOWEVER THE ECMWF MODEL BRINGS A BRIEF WINDOW OF SOME PARTIAL CLEARING AND DRYING IN FOR SATURDAY WHILE THE GFS SUGGESTS MORE CLOUDS WITH AT LEAST A FEW LINGERING SHOWERS. AT THIS POINT WILL KEEP IN THE CHANCE OF SHOWERS WITH MOSTLY CLOUDY SKIES. A BETTER CHANCE FOR MORE WIDESPREAD RAIN AND SHOWERS DEVELOPS ONCE AGAIN FOR SATURDAY NIGHT AND SUNDAY AS THE NEXT SURFACE WAVE ASSOCIATED WITH THE BROAD UPPER TROUGH DEVELOPS SOUTH OF THE REGION AND MOVES NORTH UP THE COAST. TEMPERATURES THROUGH THE LONG RANGE ARE FORECAST TO REMAIN WITHIN A FEW DEGREES OF AVERAGE FOR THIS TIME OF YEAR. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... NEAR TERM: VFR ACROSS THE NORTHERN TERMINALS THIS AFTERNOON AND MVFR FOR KBGR AND KBHB. EXPECTATION IS FOR CIGS TO DROP TO MVFR ACROSS ALL THE TERMINALS BY THIS EVENING(01Z). A PERIOD OF IFR CAN BE EXPECTED LATER TONIGHT(AFT 05Z) AND THIS WILL MAINLY BE FOR THE NORTHERN TERMINALS. DECIDED TO STAY W/MVFR THROUGH MIDDAY MONDAY. THE UPSHOT TO THIS IS THAT AN IMPROVEMENT TO VFR FOR TAF SITES BY MONDAY EVENING. SHORT TERM: VFR CONDITIONS ARE EXPECTED ACROSS THE REGION MONDAY NIGHT THROUGH WEDNESDAY. VFR WEDNESDAY NIGHT WILL GIVE WAY TO MVFR AND THEN IFR THURSDAY AS RAIN MOVES IN FROM WEST TO EAST. MVFR/IFR CONDITIONS ARE LIKELY TO PERSIST INTO FRIDAY DUE TO LOW STRATUS WITH LINGERING SHOWERS. && .MARINE... NEAR TERM: NO SCA ATTM. LATEST MODEL GUIDANCE HAS BEEN RUNNING TOO HIGH FOR THE WINDS AND ADJUSTMENTS WERE MADE TO PUSH THE SPEEDS BACK. THEREFORE, AFTER COLLABORATION W/GYX, DECISION HERE WAS TO KEEP WINDS GUSTS BELOW 25 KTS W/SUSTAINED WINDS 15+ KTS INTO MONDAY. THE OUTER WATERS BEYOND 25NM COULD SEE GUSTS TO 25KTS. WAVE HEIGHTS WERE ALSO RUNNING BELOW THE GUIDANCE INCLUDING THE LATEST SWAN GUIDANCE. SO, SEAS WERE LIMITED TO 5 FT AND THIS IS AWAY FROM THE INTRA-COASTAL ZONES. SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE ON THE WATERS MONDAY NIGHT INTO EARLY TUESDAY NIGHT. CONDITIONS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY LEVELS LATER TUESDAY NIGHT INTO WEDNESDAY. SCA CONDITIONS WILL BE POSSIBLE THURSDAY AS SE WINDS STRENGTHEN AND WAVE HEIGHTS INCREASE AHEAD OF AN OCCLUSION MOVING THROUGH WHICH WILL ALSO BRING RAIN AND THE POTENTIAL FOR FOG. THESE CONDITIONS IMPROVE FOR FRIDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT SHORT TERM...NORCROSS LONG TERM...FITZSIMMONS AVIATION...CB/HEWITT/NORCROSS MARINE...CB/HEWITT/NORCROSS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
341 PM EDT SUN APR 27 2014 .SYNOPSIS... LOW PRESSURE SOUTH OF NOVA SCOTIA WILL CONTINUE MOVING INTO THE OPEN ATLANTIC TONIGHT INTO MONDAY. HIGH PRESSURE WILL BUILD SOUTH ACROSS THE REGION MONDAY NIGHT THROUGH WEDNESDAY. && .NEAR TERM /THROUGH MONDAY/... THE CHALLENGE WILL DEFINITELY BE THE TEMPERATURES AND WHERE TO PLACE RAINFALL CHANCES. LOW PRES WAS SPINNING SE OF NOVA SCOTIA PER THE 18Z ANALYSIS. SFC TROUGH EXTENDING OFF THIS LOW EXTENDED BACK EASTERN AND CENTRAL MAINE. THE FIRST BATCH OF LIGHT RAIN/SHOWERS MOVED SSW EARLY TODAY AND ANOTHER ROUND IS APPROACHING FROM NEW BRUNSWICK. THE RAIN HAS BEEN WEAKENING AS IT RUNS INTO DRIER AIR AS SEEN BY THE LATEST SATELLITE VISIBLE IMAGERY SHOWING BREAKS IN THE CLOUDS. BEST SUPPORT FOR SUBSTANTIAL RAIN HAS BEEN OVER THE EASTERN SECTIONS OF WASHINGTON COUNTY. DECENT LLVL CONVERGENCE AND MID LEVEL FORCING IS THERE AS SEEN BY BOTH THE RAP AND NAM12. EXPECTING THIS TREND TO CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON. CARRIED CHANCE POPS(30-50%) FOR THE CWA TONIGHT W/THE HIGHEST CHANCES ACROSS NORTHERN AND EASTERN SECTIONS. AS ONE TRAVELS FURTHER W AND SW, SHOWERS WILL WEAKEN DUE TO SUBSIDENCE IN PLACE. CLOUDS WILL HANG AROUND THROUGHOUT THE NIGHT AND THIS WILL KEEP TEMPERATURES WELL ABOVE 32F WHICH SHOULD ALLOW FOR ALL LIQUID PRECIP. RAINFALL AMOUNTS HAVE BEEN LIGHT AND SEE NO SUPPORT FOR THIS TO CHANGE MUCH OVER THE NEXT 24 HRS. THEREFORE, STAYED W/QPF OF 0.10" OR LESS THROUGH MONDAY. CONDITIONS LOOK TO IMPROVE THROUGHOUT THE DAY ON MONDAY AS HIGH PRES IS FORECAST TO WEDGE DOWN FROM CANADA. SOME SUNSHINE IS EXPECTED BY MONDAY AFTERNOON ESPECIALLY ACROSS THE NORTHERN AND EASTERN SECTIONS WHILE THE CENTRAL HIGHLANDS WILL HANG ON TO MORE CLOUDS. THIS WILL LEAD TO A VARIATION IN TEMPERATURES. DECIDED TO BOOST DAYTIME HIGHS ON MONDAY UP TO READINGS AOA 50F MAINLY FOR THE NORTHERN AND EASTERN SECTIONS. CENTRAL AND WESTERN AREAS WILL HANG W/MORE CLOUDS THUS KEEPING TEMPERATURES DOWN INTO THE 40S SOMEWHAT SIMILAR TO TODAY. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... HIGH PRESSURE WILL RIDGE SOUTH ACROSS THE REGION MONDAY NIGHT THROUGH EARLY WEDNESDAY...THEN BEGIN TO MOVE EAST LATER WEDNESDAY. CLOUD COVER WILL DECREASE ACROSS THE REGION MONDAY NIGHT. MOSTLY CLEAR SKIES WILL OCCUR ACROSS THE REGION TUESDAY INTO EARLY WEDNESDAY. CLOUD COVER WILL THEN BEGIN TO INCREASE LATER WEDNESDAY...PARTICULARLY ACROSS WESTERN PORTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE AT NEAR NORMAL...TO SLIGHTLY BELOW NORMAL...LEVELS TUESDAY/WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AN UNSETTLED PATTERN WILL TAKE HOLD ONCE AGAIN FOR THE LONG RANGE AS THE RIDGE BREAKS DOWN AND THE NEXT UPPER LEVEL LOW ADVANCES TOWARD THE REGION. CLOUDS WILL INCREASE WEDNESDAY NIGHT WITH RAIN AND SHOWERS DEVELOPING WEST TO EAST FOR THURSDAY AS AN OCCLUSION MOVES THROUGH AHEAD OF A SURFACE LOW ADVANCING NORTH ALONG THE COAST. STEADIER RAIN LOOKS TO TAPER OFF THURSDAY NIGHT WITH RAIN AMOUNTS OF A HALF INCH TO AN INCH POSSIBLE BY THIS TIME. EXPECT SHOWERS TO LINGER INTO FRIDAY IN ASSOCIATION WITH THE BROAD UPPER LEVEL LOW SITUATED OVER THE GREAT LAKES BY THIS TIME AND A LINGERING SURFACE TROUGH. SOME UNCERTAINTY DEVELOPS IN THE FORECAST FOR THE BEGINNING OF NEXT WEEKEND. OVERALL, THE UNSETTLED PATTERN REMAINS HOWEVER THE ECMWF MODEL BRINGS A BRIEF WINDOW OF SOME PARTIAL CLEARING AND DRYING IN FOR SATURDAY WHILE THE GFS SUGGESTS MORE CLOUDS WITH AT LEAST A FEW LINGERING SHOWERS. AT THIS POINT WILL KEEP IN THE CHANCE OF SHOWERS WITH MOSTLY CLOUDY SKIES. A BETTER CHANCE FOR MORE WIDESPREAD RAIN AND SHOWERS DEVELOPS ONCE AGAIN FOR SATURDAY NIGHT AND SUNDAY AS THE NEXT SURFACE WAVE ASSOCIATED WITH THE BROAD UPPER TROUGH DEVELOPS SOUTH OF THE REGION AND MOVES NORTH UP THE COAST. TEMPERATURES THROUGH THE LONG RANGE ARE FORECAST TO REMAIN WITHIN A FEW DEGREES OF AVERAGE FOR THIS TIME OF YEAR. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... NEAR TERM: VFR ACROSS THE NORTHERN TERMINALS THIS AFTERNOON AND MVFR FOR KBGR AND KBHB. EXPECTATION IS FOR CIGS TO DROP TO MVFR ACROSS ALL THE TERMINALS BY THIS EVENING(01Z). A PERIOD OF IFR CAN BE EXPECTED LATER TONIGHT(AFT 05Z) AND THIS WILL MAINLY BE FOR THE NORTHERN TERMINALS. DECIDED TO STAY W/MVFR THROUGH MIDDAY MONDAY. THE UPSHOT TO THIS IS THAT AN IMPROVEMENT TO VFR FOR TAF SITES BY MONDAY EVENING. SHORT TERM: VFR CONDITIONS ARE EXPECTED ACROSS THE REGION MONDAY NIGHT THROUGH WEDNESDAY. VFR WEDNESDAY NIGHT WILL GIVE WAY TO MVFR AND THEN IFR THURSDAY AS RAIN MOVES IN FROM WEST TO EAST. MVFR/IFR CONDITIONS ARE LIKELY TO PERSIST INTO FRIDAY DUE TO LOW STRATUS WITH LINGERING SHOWERS. && .MARINE... NEAR TERM: NO SCA ATTM. LATEST MODEL GUIDANCE HAS BEEN RUNNING TOO HIGH FOR THE WINDS AND ADJUSTMENTS WERE MADE TO PUSH THE SPEEDS BACK. THEREFORE, AFTER COLLABORATION W/GYX, DECISION HERE WAS TO KEEP WINDS GUSTS BELOW 25 KTS W/SUSTAINED WINDS 15+ KTS INTO MONDAY. THE OUTER WATERS BEYOND 25NM COULD SEE GUSTS TO 25KTS. WAVE HEIGHTS WERE ALSO RUNNING BELOW THE GUIDANCE INCLUDING THE LATEST SWAN GUIDANCE. SO, SEAS WERE LIMITED TO 5 FT AND THIS IS AWAY FROM THE INTRA-COASTAL ZONES. SHORT TERM: SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE ON THE WATERS MONDAY NIGHT INTO EARLY TUESDAY NIGHT. CONDITIONS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY LEVELS LATER TUESDAY NIGHT INTO WEDNESDAY. SCA CONDITIONS WILL BE POSSIBLE THURSDAY AS SE WINDS STRENGTHEN AND WAVE HEIGHTS INCREASE AHEAD OF AN OCCLUSION MOVING THROUGH WHICH WILL ALSO BRING RAIN AND THE POTENTIAL FOR FOG. THESE CONDITIONS IMPROVE FOR FRIDAY. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT SHORT TERM...NORCROSS LONG TERM...FITZSIMMONS AVIATION...HEWITT/NORCROSS MARINE...HEWITT/NORCROSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
703 PM EDT MON APR 28 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 423 PM EDT MON APR 28 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A NEGATIVE TILT MID/UPPER LEVEL TROUGH FROM THE NRN ROCKIES TO THE CENTRAL PLAINS AND MID MS VALLEY. DOWNSTREAM A RIDGE EXTENDED FROM THE MID ATLANTIC THROUGH THE ERN LAKES TO WRN HUDSON BAY. AT THE SFC...GUSTY EAST WINDS PREVAILED AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER ERN NEBRASKA. A BAND OF RAIN OVER NRN WI SUPPORTED BY 295K-300K ISENTROPIC LIFT WAS MAKING VERY SLOW PROGRESS IN LIFTING TO THE NORTH AS IT ENCOUNTERS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 800 MB) TO THE NORTH AND EAST...PER 12Z APX SOUNDING. SOME PCPN MAY DEVELOP ALONG THE WI BORDER THIS EVENING BUT SINCE IT SHOULD BE RELATIVELY LIGHT...MAINLY SPRINKLES...ONLY CHANCE POPS WERE INCLUDED. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...EXPECT WIDESPREAD PCPN TO SPREAD INTO THE SOUTH LATE TONIGHT AND ACROSS THE REST OF THE CWA TUE MORNING. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE REGION WILL FALL UNDER THE TROWAL REGION NORTH OF THE MID/UPPER LOW...PER MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TUE. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS. UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE INTERIOR...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE WRN THIRD TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE ANY ACCUMULATIONS WITH SNOW AMOUNTS ONLY TO AROUND AN INCH EXPECTED ON GRASSY OR SNOW COVERED AREAS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 423 PM EDT MON APR 28 2014 MUCH OF THE LONG TERM FORECAST WILL DEAL WITH THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS THAT WILL GRADUALLY LIFT NORTHEAST THROUGH MUCH OF THE REST OF THE WORK WEEK. THE STRONGEST WAVE OF PRECIPITATION WILL MOVE NORTH THROUGH THE AREA ON TUESDAY AND SHOULD BE SITUATED OVER WESTERN LAKE SUPERIOR AND THE WESTERN THIRD OF THE U.P. AT THE START OF THE LONG TERM PERIOD. THIS WILL CONTINUE TO ROTATE NORTHWEST TUESDAY NIGHT AND LEAD TO A LITTLE BIT OF A BREAK ON THE PRECIPITATION FOR TUESDAY EVENING OVER THE CENTRAL/EAST. AS THE SURFACE LOW MOVES UP INTO THE GREAT LAKES REGION...A MID LEVEL TROUGH WILL SLIDE NORTH THROUGH THE AREA LATE TUESDAY NIGHT THROUGH WEDNESDAY. THINK THE HEAVIEST PRECIP WOULD BE OVER THE EAST THIRD...BUT STILL WOULD EXPECT SCATTERED/NUMEROUS SHOWERS OVER THE WEST/CENTRAL. BETTER DEEP MOISTURE SHIFTS OVER THE WESTERN LAKE AFTER THAT...AND WILL LIKELY LEAD TO A MORE SCATTERED NATURE TO THE SHOWERS. THIS WILL CONTINUE THROUGH THE FIRST PART OF THE WEEKEND AS THE AS THE UPPER LOW SPINS AND BROADENS/WEAKENS. THUS...WILL CONTINUE TO SHOW A GRADUAL DECREASING TREND TO THE POPS. WITH THE POTENTIAL FOR WEAK DISTURBANCES ROTATING THROUGH...THERE MAY BE PERIODS WHERE POPS NEED TO BE BUMPED UP...BUT PINNING THOSE DOWN AT THIS TIME IS TOO DIFFICULT. AS FOR PRECIP TYPE...SHOULD BE ENOUGH WARM AIR WRAPPING IN DURING THE DAY TOMORROW TO CHANGE THE PRECIP OVER TO RAIN OVER MUCH OF THE AREA BY TUESDAY EVENING (EXCEPT FOR A LINGERING MIX NEAR IRONWOOD). THE WARM AIR CONTINUES TO MOVE WEST AROUND THE LOW (REMAINING AROUND 2-4C AT 850MB) THROUGH WEDNESDAY EVENING AND WILL KEEP EVERYTHING AS RAIN. THEN AS THE FLOW STARTS TO BECOME A LITTLE MORE NORTHERLY ON WEDNESDAY NIGHT AND INTO THURSDAY...TEMPERATURES ALOFT BEGIN TO COOL FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA AND COULD LEAD TO A TRANSITION TO TO MORE OF A RAIN/SNOW MIX HEADING INTO THURSDAY/FRIDAY. OPTED TO FOLLOW THE GENERAL IDEA SHOWN BY THE 1000-850MB THICKNESS AND WETBULB0 HEIGHTS THROUGH THE FORECAST PERIOD SINCE IT WAS LARGELY DEALING WITH A NEAR SURFACE WARM LAYER. DID PUT IN SOME FOG FOR THE FAVORED UPSLOPE HIGHER TERRAIN LOCATIONS OF THE CENTRAL/NORTH-CENTRAL ON TUESDAY NIGHT INTO WEDNESDAY WITH THE FAVORABLE EASTERLY UPSLOPE FLOW OF MOIST AIR. ELSEWHERE...WOULD EXPECT IT TO BE JUST A LOW STRATUS DECK. ALL IN ALL...LOOKS TO BE A COOL/CLOUDY/SHOWERY PERIOD THROUGH THE FIRST HALF OF THE WEEKEND. UPPER TROUGH/LOW FINALLY SHIFTS EAST OF THE AREA FOR THE SECOND HALF OF THE WEEKEND...BUT MODELS DIFFER ON EVOLUTION OF THE UPPER LEVEL PATTERN AT THAT POINT. THE GENERAL IDEA IS FOR MORE ZONAL FLOW OR WEAK UPPER LEVEL RIDGING TO DEVELOP OVER THE NORTH-CENTRAL CONUS...WHICH SHOULD LEAD TO A LITTLE DRIER PERIOD THAN SEEN THIS WEEK. THERE ARE HINTS IN THE 12Z GEM/GFS/ECMWF THAT A WEAK DISTURBANCE WILL SHIFT EAST ACROSS THE AREA ON SUNDAY AND BRING SOME SHOWERS. OTHERWISE...MONDAY IS LOOKING LIKE IT MAY END UP DRY WITH THE WEAK UPPER RIDGE SHIFTING CLOSER TO THE AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 703 PM EDT MON APR 28 2014 VFR CONDITIONS WILL PREVAIL UNTIL LATE TONIGHT AT ALL SITES. INCREASING MOISTURE AHEAD OF A WARM FRONT WILL BRING AN INCREASING CHANCE OF RAIN AND SNOW LATE TONIGHT AT ALL TAF SITES AS CIGS LOWER TO MVFR. A MIX OF RAIN AND SNOW WILL MOVE IN DURING THE MORNING WITH CIGS LIKELY LOWERING INTO THE IFR/LIFR RANGE. THE BEST CHANCE FOR SNOW WILL BE OVER THE WEST TOWARD CMX AND ESPECIALLY IWD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 423 PM EDT MON APR 28 2014 EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE INTO TUE EVENING AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER ERN NEBRASKA AND A STRONG HIGH OVER HUDSON BAY. ENE GALES TO 35 KNOTS ARE ALSO POSSIBLE CENTRAL LAKE SUPERIOR TUE BUT SINCE THERE WAS STILL UNCERTAINTY WHETHER THE 30 KNOTS WINDS WILL INCREASE TO GALES...THE WATCH WAS RETAINED FOR THIS LOCATION. THE WINDS WILL DIMINISH TUE EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO FRI AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 423 PM EDT MON APR 28 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TUESDAY MORNING THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN LATER THIS WEEK AS A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECT UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR LSZ264>266. GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ TUESDAY FOR LSZ162-263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB HYDROLOGY...SRF/TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 PM EDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 432 PM EDT SUN APR 27 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A NEGATIVE TILT MID/UPPER LEVEL TROUGH THROUGH THE NW CONUS WITH A LOW OVER WRN KS AND A DOWNSTREAM RIDGE FROM THE SE CONUS THROUGH WRN LAKES INTO MANITOBA. AT THE SFC...A BRISK ERLY FLOW PREVAILED THROUGH THE NRN LAKES BETWEEN HIGH PRES OVER HUDSON BAY AND A DEEP LOW OVER NW KS. AN INITIAL BAND OF LIGHT PCPN WAS PRODUCING MAINLY JUST SPRINKLES INTO THE FAR WRN CWA NEAR IWD AS IT ENCOUNTERS THE VERY DRY LAYER BELOW 750 MB. HOWEVER...A MORE SUBSTANTIAL AREA OF RAIN OVER WRN INTO N CNTRL WI...SUPPORTED BY 300K ISENTROPIC LIFT WAS LIFTING TOWARD UPPER MI. TONIGHT...RADAR TRENDS AND SHORT TERM MODELS SUGGEST THAT SOME LIGHT SHOWERS WILL MOVE INTO THE WEST LATE THIS AFTERNOON AND EVENING. HOWEVER...THERE IS A LOWER CHANCE THAT THERE WILL BE MEASURABLE PCPN GIVEN THE AMOUNT OF DRY AIR TO OVERCOME WITH THE ERLY LOW LEVEL INFLOW. FARTHER TO THE EAST...OVER S CNTRL UPPER MI...THE DRY AIR...PER 12Z APX SOUNDING...SHOULD BE MORE EFFECTIVE AT SLOWING THE ADVANCE AND REDUCING PCPN CHANCES. WITH EVAPORATIVE COOLING AT THE LEADING EDGE OF THE PCPN...SOME SNOW OR SLEET MAY ALSO MIX IN WITH THE RAIN LATE THIS EVENING AND OVERNIGHT...PER NAM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS. MON...THE MODELS WERE IN SLIGHTLY BETTER AGREEMENT IN HANDLING THE ADVANCE OF PCPN INTO UPPER MICHIGAN. THE NAM/GFS/ECMWF WERE NOW ON THE SLOWER SIDE COMPARED TO GEM. AS THE MID/UPPER LEVEL LOW SLOWLY WOBBLES TO THE NORTHEAST AND AN ELONGATED TROUGH/FRONT EXTENDS FROM SRN IA INTO NRN INDIANA. ANOTHER BAND OF RAIN WILL MOVE TOWARD UPPER MI WITH INCREASING 300K-305K ISENTROPIC ASCENT NORTH OF THE 850 MB WARM FRONT THROUGH CNTRL WI. THERE IS STILL LIKELY TO BE SHARP CUTOFF TO THE NRN EDGE OF THE PCPN BAND THROUGH CNTRL UPPER MI. THE HIGHEST CHANCES WILL REMAIN ALONG THE WI BORDER WITH ONLY A SLIGHT CHANCE OVER THE NORTH. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 432 PM EDT SUN APR 27 2014 UPPER LOW OVER THE CENTRAL PLAINS MONDAY AFTERNOON AND ASSOCIATED SFC LOW AND WARM FRONT WILL BE MAIN FOCUS FOR THE FORECAST THIS UPCOMING WEEK. MODELS VERY LOCKED INTO IDEA THAT WHILE WIDESPREAD SHRA AND TSRA AND SEVERE WEATHER IMPACT MID TO LOWER MISSISSIPPI RIVER VALLEY...ADDITIONAL SHRA/TSRA DEVELOP LATE MONDAY AFTN ALONG WARM FRONT EXTENDING TO THE EAST OF SFC LOW OVER NEB. THIS IS IN RESPONSE TO SHORTWAVE/PV ANAMOLY LIFTING AHEAD OF PARENT UPPER LOW. POSSIBLE THAT ADDITIONAL SHRA WILL ALREADY BE LIFTING TOWARD UPR MICHIGAN AS WELL DUE TO REMNANTS OF SHRA/TSRA DEVELOPING OVER THE UPPER MISSISSIPPI RIVER VALLEY MONDAY MORNING PER SSW-NNE ORIENTED FORWARD PROPAGATING CORFIDI VECTORS AND H85-H7 MOSITURE TRANSPORT. AREA OF SHRA/TSRA ALONG WARM FRONT WILL GLIDE TOWARD UPR MICHIGAN OVERNIGHT INTO TUESDAY MORNING DUE TO THE ARRIVAL OF SHORTWAVE AND H85-H5 Q-VECTOR CONVERGENCE ALONG WITH VEERING H85-H7 FLOW FM ESE TO MORE SSW. FOLLOWING THE Q-VECTOR CONVERGENCE AND RIBBON OF MOISTURE TRANSPORT...EXPECT MOST PRECIPITATION TO OCCUR IN THE MORNING. BASED ON 1000-850MB THICKNESSES/H85 TEMPS AND HEIGHT OF WBZERO...MAY SEE SNOW OR A RAIN/SNOW MIX OVER HIGHER TERRAIN OF WEST AND NCNTRL UPR MICHIGAN PERHAPS EVEN LINGERING INTO MID AFTN. MINOR SNOW ACCUMULATIONS SEEM POSSIBLE...ESPECIALLY ON GRASSY SURFACES. WILL LEAVE OUT OF HAZARDOUS WEATHER OUTLOOK FOR NOW AS TRAVEL WOULD PROBABLY BE ONLY MINIMALLY IMPACTED. BY LATE AFTN...EXPECT CHANGE OVER TO RAIN AS H85 TEMPS SURGE ABOVE ZERO. THIS MAY BE OCCURRING WHEN MAJORITY OF HEAVIER PRECIPITATION IS COMING TO AN END THOUGH. BY TUE EVENING...FORECAST SOUNDINGS SHOW DRYING ABOVE H9...SO THERE MAY BE DRIZZLE. TEMPS WILL CONTINUE TO RISE SFC-H85 SO BY THAT TIME WILL ONLY BE DEALING WITH LIQUID PRECIP. ON WEDNESDAY...PRIMARY SHORTWAVE LIFTS NORTH ACROSS THE UPPER GREAT LAKES. SEEMS TO BE A TREND FOR BEST MOISTURE TRANSPORT TO MISS UPR MICHIGAN TO THE EAST...ALLOWING BULK OF RAIN ON WEDNESDAY TO SURGE NORTH ACROSS THE LOWER LAKES. HOWEVER...SIGNAL THAT HIGHER THETA-E AT H8-H7 WILL BE WRAPPING WESTWARD ACROSS UPR MICHIGAN ON CYCLONIC NORTH SIDE OF FILLING SFC-H85 LOWS. RAIN ON WEDNESDAY WOULD ONLY BE BOLSTERED OVER HIGHER TERRAIN OF WESTERN AND NORTH CENTRAL UPPER MICHIGAN WITH NE BLYR WINDS. WEDNESDAY NIGHT INTO THURSDAY...THE VERTICALLY STACKED LOW PRESSURE SYSTEM REMAINS NEARLY STATIONARY OVER THE UPPER GREAT LAKES. UNSETTLED WEATHER PATTERN AND WILL KEEP WITH THE CHANCES THAT CONSENSUS OF MODELS SHOWS. THE GREATEST CHANCES OF RAIN WILL BE ALONG AND NORTH AND WEST OF H85 LOW WHERE HIGHER THETA-E CONTINUES TO WRAP AROUND THE LOW AND ALSO WHERE LINGERING Q-VECTOR CONVERGENCE IS LOCATED. YET...CANNOT RULE OUT PRECIP JUST ABOUT ANYWHERE OVER THE CWA AS OTHER SHORTWAVES WILL PROBABLY BE CYCLING AROUND THE MAIN UPPER LOW CENTER AND THERE SHOULD BE PLENTY OF LOW-MID LEVEL MOISTURE REMAINING OVER REGION. DO NOT EXPECT THE PRECIP THAT OCCURS BEYOND WEDNESDAY EVENING TO BE HEAVY AS RICHER MOISTURE WILL BE HEADING WELL TO THE EAST OF THE REGION BY THAT TIME. GRADUALLY COOLING TEMPERATURES ALOFT AND EVENTUALLY AT THE SFC /H85 TEMPS DROPPING BLO 0C PER GFS/ECMWF/ COULD RESULT IN MIXED RAIN AND SNOW OVER PORTIONS OF CWA LATER WEDNESDAY NIGHT INTO THURSDAY MORNING AND AGAIN THURSDAY NIGHT INTO FRIDAY MORNING. MAY EVEN SEE MIX LATER FRIDAY NIGHT INTO SATURDAY MORNING. ONLY SLIGHT CHANCES FOR POPS BY THAT TIME THOUGH AS SYSTEM WILL BE UNRAVELLING AS IT LIFTS EAST AND NORTH AWAY FM LK SUPERIOR/UPR MICHIGAN. UPPER LEVEL TROUGH STILL FORECAST OVER THE REGION NEXT WEEKEND...SO NO WARM UP IS IN STORE. COULD BE MORE RAIN/SNOW BY NEXT SUNDAY AS THERE ARE HINTS OF STRONGER SYSTEM WORKING THROUGH AT THAT TIME. HOWEVER...SINCE THE TIMING FOR THAT SYSTEM WILL BE COMPLETELY DICTATED BY THE UPPER LOW THIS WEEK AND HOW QUICK IT DEPARTS...THERE IS CONSIDERABLE UNCERTAINTY IN HOW ALL THESE DETAILS WILL EVENTUALLY WORK OUT. THUS...CHANGES TO MODEL CONSENSUS BEYEOND THURSDAY WERE MINIMAL GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 139 PM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS FROM THE WEST THIS AFTERNOON INTO THIS EVENING. THERE COULD BE SOME INTERMITTENT LIGHT RAIN AT KIWD BEGINNING THIS EVENING AS MID LEVELS BEGIN TO MOISTEN...BUT CONDITIONS ARE EXPECTED TO REMAIN VFR. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 432 PM EDT SUN APR 27 2014 EAST WINDS WILL INCREASE TONIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. EXPECT ENE GALES TO 35KTS OVER WESTERN LK SUPERIOR TOWARD DULUTH INTO TUE MORNING. EAST GALES ARE THEN EXPECTED LATE TONIGHT INTO MON OVER THE REST OF THE WESTERN LAKE. WINDS WILL GRADUALLY DIMINISH TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 432 PM EDT SUN APR 27 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS...AND THE STURGEON RIVER NEAR NAHMA JUNCTION IN DELTA COUNTY. AT LEAST THROUGH MONDAY NONE OF THESE RIVERS ARE EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS MAY START TO RISE AGAIN LATER THIS WEEK AS A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECT UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY LATE THIS WEEK. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 AM EDT /10 AM CDT/ TUESDAY FOR LSZ162. GALE WARNING FROM 2 AM TO 8 PM EDT MONDAY FOR LSZ263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...JLB HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
140 PM EDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 515 AM EDT SUN APR 27 2014 WV IMAGERY AND RUC ANALYSIS SHOWS A NEG-TILT TROUGH OVER THE CENTRAL PLAINS WITH BUILDING 5H HGTS AND AMPLIFYING RDG OVER THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDING FROM HUDSON BAY INTO THE WRN GREAT LAKES RESULTED IN A DRY ERLY FLOW ACROSS UPPER MI EARLY THIS MORNING. IR SATELLITE ONLY REVEALS SOME BLOWOFF HIGH CLOUDS FM CONVECTION OVER THE DAKOTAS AND MN SPILLING INTO UPPER MI. TODAY INTO TONIGHT...MODELS INDICATE THE STRONG MID LEVEL LOW NEAR THE AZ/CO BORDER WILL LIFT NORTH INTO NEBRASKA LATE TONIGHT AS THE MID-LVL AND SFC LOW BECOME VERTICALLY STACKED. WAA PCPN LIFTING THROUGH MN AND NRN WI EARLY THIS MORNING AHEAD OF THE 850 MB WARM FRONT HAS BEEN BREAKING APART ON THE NRN EDGE AS IT ENCOUNTERS VERY DRY AIRMASS AND DRY ERLY FLOW CIRCULATING AROUND HUDSON BAY HIGH. DRYNESS OF AIRMASS IN PLACE OVER THE UPPER GREAT LAKES VERY EVIDENT FM 00Z KGRB AND KINL SNDGS. GIVEN DRY AIRMASS IN PLACE WILL LEAN TOWARD DRIER SOLN OF NAM AND REG GEM FOR OUR FCST AREA TODAY INTO TONIGHT OVER SOMEWHAT MORE AGGRESSIVE GFS SOLN. GENERALLY EXPECT THAT PCPN WILL STAY TO THE SOUTH OF THE CWA THROUGH TODAY WITH POSSIBLY SOME LIGHT MIXED PCPN (NO MORE THAN A COUPLE OF HUNDREDTHS OF AN INCH) FINALLY REACHING INTO THE FAR SW PORTION OF THE CWA TONIGHT. TEMPS WILL REMAIN BELOW NORMAL...WITH HIGHS TODAY RANGING FROM THE UPPER 30S/LOWER 40S ALONG GREAT LAKES IN E-NE FLOW TO MID 40S TO AROUND 50 FARTHER INLAND FROM THE GREAT LAKES. LOWS TONIGHT WILL BE IN THE LOWER TO MID 30S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 409 AM EDT SUN APR 27 2014 CHALLENGING LONG TERM IN SPITE OF GOOD MODEL TO MODEL AGREEMENT AND DECENT RUN TO RUN CONTINUITY. A VIGOROUS UPPER LEVEL SHORTWAVE CURRENTLY NEAR THE FOUR CORNERS WILL DEEPEN SIGNIFICANTLY AS IT MOVES INTO THE CENTRAL PLAINS. THE SYSTEM WILL BECOME OCCLUDED AND VERTICALLY STACKED BY 12Z MON WITH THE 986MB SFC LOW OVER NE. THE UPPER LOW WILL BROADEN AND WEAKEN WHILE BECOMING CENTERED NEAR IA BY 00Z WED...WITH THE SYSTEM AT THIS POINT BEING SANDWICHED BETWEEN A STOUT UPPER RIDGE OVER THE W COAST AND A SLIGHTLY WEAKER RIDGE EXTENDING UP THE E COAST AND CURVING BACK OVER HUDSON BAY. THE BLOCKING PATTERN WILL FORCE THE UPPER LOW TO HANG OUT OVER THE NCENTRAL CONUS THROUGH THE MIDDLE OF THIS WEEK WHILE SLOWLY FILLING. MULTIPLE SHORTWAVES WILL BE ROTATING AROUND THE LOW ACCORDING TO MODELS. ADDITIONAL UPPER LEVEL ENERGY WILL LATE IN THE WEEK INTO NEXT WEEKEND...ALLOWING FOR A FRESHENING OF THE PATTERN AND THE UPPER LOW TO EXIT THE REGION. AS PREVIOUSLY MENTIONED...MODELS AGREE WELL AT THIS TIME...BUT THIS SYSTEM WILL UNDERGO A LOT OF CHANGE IN THE NEXT 1-2 DAYS. IT WILL BE INTERESTING TO SEE HOW MODELED MASS FIELDS CHANGE AFTER A SIGNIFICANT SEVERE WEATHER EVENT UNFOLDS ACROSS THE SCENTRAL CONUS TODAY INTO MONDAY. MOST UNCERTAIN AND RIPE FOR CHANGE ARE DETAILS RELATED TO SHORTWAVE ENERGY PROGGED TO ROTATE THROUGH THE CWA A FEW TIMES THIS WEEK. OVERALL...WILL NOT GET TOO SPECIFIC WITH DETAILS YET AND WILL NOT CHANGE THE FORECAST MUCH /ESPECIALLY AFTER MON/. FOR MON...MOISTURE TRANSPORT WILL FOCUS INTO THE REGION ALONG AND BEHIND A WARM FRONT THAT MODELS SHOW STALLING NEAR OR OVER THE FAR SWRN CWA. THINK THAT MODELS ARE ON THE RIGHT TRACK SHOWING A TIGHT GRADIENT TO PRECIP /WHICH ALSO LINES UP WELL WITH PREVIOUS FORECAST/ DUE TO VERY DRY AIR /1000-700MB RH LESS THAN 30 PERCENT/ OVER THE NERN CWA AS A RESULT OF A HUDSON BAY HIGH OF 1050MB. THREW OUT THE NAM FOR THIS PERIOD AS IT WAS BY FAR THE FARTHEST SW WITH THE PRECIP AND OTHER MODELS WERE IN GOOD AGREEMENT IN BRINGING SOME PRECIP TO THE SWRN CWA. PRECIP SHOULD BE ALL RAIN ON MON. THE UPPER LOW MUST BE HUNGRY MON NIGHT BECAUSE MODELS SHOW THE LOW SUCKING IN A WEAK UPPER LOW FROM QUEBEC...FORMING AN UPPER TROUGH OVER THE WRN/NRN CWA MON NIGHT INTO TUE MORNING. COLDER AIR IS BROUGHT IN WITH THE WEAK LOW /IF THAT SCENARIO DOES PLAY OUT/...WHICH WOULD BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHER TERRAIN OF THE NWRN CWA. AT THE TIME SNOW WOULD BE FAVORED PRECIP WILL BE MINIMAL SO NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED. ANOTHER SLUG OF MOISTURE/RAIN COMES ON TUE AS MODELS CURRENTLY SHOW A SHORTWAVE MOVING ROTATING THROUGH THE REGION. THE TIMING COULD CHANGE...BUT GIVEN THAT MODELS CURRENTLY AGREE FAIRLY WELL ON THIS AND THAT THE FORECAST HAS LIKELY OR GREATER POPS...WILL NOT CHANGE THINGS SIGNIFICANTLY. MODELS INDICATE QPF ON TUE OF 0.25 INCHES OVER THE WRN CWA TO OVER A HALF INCH OVER THE ERN CWA. DRIER MID-UPPER LEVEL AIR MOVES IN ON TUE NIGHT...AND WITH LOW LEVEL MOISTURE STAYING PUT DRIZZLE MAY BE THE PRIMARY PRECIP TYPE TUE NIGHT. WILL NOT GET THAT SPECIFIC AT THIS POINT AND JUST CONTINUE TO CALL FOR SOME RAIN. THE UPPER LOW MOVES INTO THE CWA ON WED...BRINGING AN OCCLUDING SFC LOW INTO THE ERN CWA FROM THE S. THIS WOULD LEAD TO ANOTHER ROUND OF RAIN ON WED...ESPECIALLY IF A TROWAL SETS UP ON THE SW SIDE OF THE 850MB LOW /STACKED OVER THE SFC LOW/. AGAIN...LIKELY POPS IN THE PREVIOUS FORECAST LOOK REASONABLE GIVEN SOME UNCERTAINTY SO WILL NOT MAKE SIGNIFICANT CHANGES TO THAT. HAVE FORECASTED STORM TOTAL QPF FROM MONDAY THROUGH WED OF AROUND 1.00 INCHES OVER NRN UPPER MI TO 1.50-2.00 INCHES ALONG THE WI BORDER. WITH THE PATTERN CHANGING AS THE UPPER LOW WEAKENS AND MOVES OUT LATER IN THE WEEK...SIGNIFICANT PRECIP IS LESS LIKELY SO GOING CHANCE POPS IN THE PREVIOUS FORECAST SHOULD HANDLE THINGS WELL. WILL USE A CONSENSUS OF MODELS GUIDANCE DURING THIS PERIOD. COULD SEE A RETURN OF MIXED PRECIP AS COOLER AIR MAY MOVE IN FROM THE NW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 139 PM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS FROM THE WEST THIS AFTERNOON INTO THIS EVENING. THERE COULD BE SOME INTERMITTENT LIGHT RAIN AT KIWD BEGINNING THIS EVENING AS MID LEVELS BEGIN TO MOISTEN...BUT CONDITIONS ARE EXPECTED TO REMAIN VFR. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 515 AM EDT SUN APR 27 2014 EAST WINDS INCREASE TODAY INTO TONIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. EXPECT NE GALES TO 35KTS OVER WESTERN LK SUPERIOR TOWARD DULUTH BY LATE AFTERNOON CONTINUING INTO TUE MORNING. EAST GALES ARE THEN EXPECTED LATE TONIGHT INTO MON OVER THE REST OF THE WESTERN LAKE. WINDS WILL GRADUALLY DIMINISH TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 409 AM EDT SUN APR 27 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. WHILE THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION ARE NOT EXPECTED TO REACH FLOOD STAGE IN THE SHORT TERM...THE STURGEON RIVER NEAR CHASSELL REMAINS NEAR FLOOD STAGE AND IS EXPECTED TO REMAIN STEADY OR SLOWLY FALL INTO EARLY THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. A LARGE LOW PRESSURE SYSTEM WILL MOVE INTO THE GREAT LAKES BY THE MIDDLE OF THIS WEEK. PERIODS OF RAIN ARE POSSIBLE FROM LATE MONDAY THROUGH THURSDAY WITH THE POTENTIAL FOR TOTAL AMOUNTS AN INCH TO TWO INCHES. THIS WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS OVER THE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM EDT /4 PM CDT/ THIS AFTERNOON TO 11 AM EDT /10 AM CDT/ TUESDAY FOR LSZ162. GALE WARNING FROM 2 AM TO 8 PM EDT MONDAY FOR LSZ263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...JLB MARINE...VOSS HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1252 PM EDT SUN APR 27 2014 .AVIATION... //DISCUSSION... VFR CONDITIONS WILL REMAIN IN PLACE TODAY THROUGH MONDAY MORNING AS LOW LEVEL DRY AIR FROM THE EAST BATTLES MOISTURE MOVING IN FROM THE WEST. THE RESULT WILL BE VARYING AMOUNTS OF MID AND HIGH CLOUDS WITH PERSISTENT EASTERLY SURFACE WIND. MEANINGFUL RAINFALL IS NOW EXPECTED TO HOLD OFF UNTIL MONDAY AFTERNOON STARTING IN THE DTW AREA. //DTW THRESHOLD THREATS... * NONE. && .PREV DISCUSSION...ISSUED 403 AM EDT SUN APR 27 2014 SHORT TERM...TODAY AND TONIGHT SURFACE RIDGING IS IN PLACE THIS MORNING FROM JAMES BAY DOWN THROUGH THE LOWER PENINSULA OF MICHIGAN WITH THE LOW TO MIDLEVEL RIDGE AXIS RESIDING WELL WEST OF THE STATE. NOT SURPRISINGLY...THE WEATHER OVER SOUTHEASTERN MICHIGAN HAS BEEN VERY QUIET OVERNIGHT THANKS TO THE STABLE AIRMASS THAT IS IN RESIDENCE. THE LOW STRATOCUMULUS THAT PLAGUED THE NORTHERN CWA FOR MUCH OF TODAY...FORCED FROM COLD AIR ADVECTION....RAPIDLY DISSIPATED THE PAST COUPLE OF HOURS AS HIGH CLOUD SPILLING OVER THE MIDLEVEL RIDGE TRACKED OVERHEAD. THE LOSS OF CLOUD TOP COOLING SEEMED TO HAVE AN ALMOST INSTANTANEOUS IMPACT ON THE CLOUD. IT IS DIFFICULT TO COME UP WITH AN ACCURATE PORTRAYAL OF CLOUDS FOR THE DAYBREAK HOUR AS IT IS A TOUGH TASK TO GAIN SOME HANDLING ON THE OPACITY OF THE CLOUD. WITH THE BLOCKED NATURE OF THE FLOW/TROUGH AXIS REMAINING OVER MUCH OF THE CENTRAL PLAINS TODAY...FAVOR A MORE TRANSPARENT HIGH CLOUD AND WILL BE VERY OPTIMISTIC WITH THE SKY COVER FORECAST FOR TODAY. MODERATION OF THE AIR MASS OF SOME 4C AT 850MB BY THE AFTERNOON ALONG WITH THE IDEA OF MORE INSOLATION...DECIDED TO GO ON THE HIGH END OF GUIDANCE WITH SOME LOCATIONS OVERACHIEVING. HIGHS TODAY ARE EXPECTED TO REACH THE LOWER TO MIDDLE 50S. LOW DEWPOINTS AND CHILLY EASTERLY WIND TRAJECTORIES WILL KEEP SOME DENIZENS OF SOUTHEASTERN MICHIGAN UNSATISFIED FOR A SECOND DAY. THE MIDLEVEL RIDGE AXIS IS FORECASTED TO REMAIN WEST OF SOUTHEASTERN MICHIGAN THROUGH 12Z MONDAY. IN ADDITION...COLD NEAR SURFACE DRAINAGE FLOW IS EXPECTED OFF OF THE CANADIAN SURFACE HIGH. FOR THESE REASONS...REMOVED ALL MENTION OF PRECIPITATION FOR TONIGHT. COULD SEE SOME VIRGA APPROACH LENAWEE AND WASHTENAW COUNTIES AROUND 12Z...BUT FEEL THE POTENTIAL TO MEASURE A HUNDREDTH IS TOO LOW TO WARRANT A PRECIPITATION MENTION. LONG TERM... CUTOFF UPPER LOW POSITIONED OVER NEBRASKA BY MONDAY WILL REMAIN THE PREVALENT LARGE SCALE FEATURE THROUGHOUT THE UPCOMING WORK WEEK AS THE CIRCULATION/TROUGH UNDERGOES CONSIDERABLE EXPANSION IN SCALE. THE CIRCULATION CENTER AND ASSOCIATED MEAN TROUGH AXIS WILL ONLY SLOWLY MIGRATE EASTWARD WITH TIME...A POSITIONING THAT LEAVES SOUTHEAST MICHIGAN FIRMLY WITHIN THE EASTWARD FLANK OF THE LOWER HEIGHT FIELD DURING THE EARLY AND MIDWEEK PERIODS. DEEPENING DOWNSTREAM SOUTHWEST FLOW WILL INITIATE A STRONG LOW-MID LEVEL THETA-E AND WARM AIR ADVECTIVE RESPONSE TODAY AND TONIGHT...THE NET RESULT BEING A STEADY NORTHEASTWARD EXPANSION IN 850-925 MB ISENTROPIC ASCENT AS THE ELEVATED WARM FRONTAL SLOPE WORKS INTO SOUTHEAST MICHIGAN MONDAY AND MONDAY NIGHT. THERE REMAINS SOME UNCERTAINTY YET IN HOW QUICKLY THIS PROCESS UNFOLDS AND TRANSLATES NORTHWARD THROUGH THE DAYLIGHT HOURS ON MONDAY...OWING TO THE OVERALL DEPTH OF THE EXISTING DRY LAYER RETAINED WITH THE SURFACE-925 MB EASTERLY GRADIENT. THIS PARTICULAR PATTERN OFTEN FAVORS A SLOWER EVOLUTION...SUPPORTING THAT OF THE ECMWF/NAM IN PROVIDING A MORE INCREMENTAL RAMP UP OF POPS FROM SOUTH TO NORTH...THE TRI-CITIES/THUMB LARGELY SEEING A DRY START TO THE WEEK. LARGE SCALE ASCENT WILL BE AUGMENTED BY BOTH FAVORABLE EXIT REGION JET DYNAMICS AND SOME FORM OF WEAK CVA AS SHREDS OF MID LEVEL ENERGY WORK THROUGH THE UPSTREAM CIRCULATION. THIS WILL SUPPORT A HIGHER END COVERAGE OF SHOWERS /CONTAINING A FEW RUMBLES OF THUNDER/ BY LATE MONDAY INTO MONDAY NIGHT. QPF POTENTIAL IN THE HALF INCH RANGE WITH THIS FIRST EPISODE OF PRECIPITATION. THE SUBSTANTIAL CLOUD COVER AND INCREASING PROSPECTS FOR SHOWERS WITHIN AN EASTERLY FLOW WILL LOCK TEMPERATURES WITHIN THE LOWER TO MIDDLE 50S AREAWIDE. LARGER SCALE PATTERN WILL CONTINUE TO SUPPORT ADDITIONAL ROUNDS OF SHOWERS WITHIN THE TUESDAY AND WEDNESDAY PERIODS...THE DETAILS SENSITIVE TO PROPER PLACEMENT OF THE GOVERNING BACKGROUND DYNAMICS TIED ADDITIONAL SHORTWAVE ENERGY LODGED IN THE BROADER CYCLONIC FLOW. 00Z MODEL GUIDANCE WOULD SUGGEST THE SURFACE WARM FRONT WILL SHIFT THROUGH ON TUESDAY...PERHAPS PROVIDING A LOW LEVEL ANCHOR POINT FOR ADDITIONAL DEVELOPMENT GIVEN AN ADDED DIURNAL COMPONENT AND CONTINUED FAVORED PLACEMENT OF THE ATTENDANT UPPER JET STREAK. STILL THE POTENTIAL FOR TEMPERATURES TO MAKE A LATE RUN POST- FRONTALLY INTO THE MIDDLE AND UPPER 60S ON TUESDAY. HIGHER END POPS REMAIN WARRANTED THROUGH WEDNESDAY GIVEN THE PATTERN PERSISTENCE...ALTHOUGH THERE MAY BE A NOTEWORTHY BREAK IN ACTIVITY AT SOME POINT WITHIN ANY POCKETS OF MID LEVEL SUBSIDENCE THAT CAN FILL IN IMMEDIATELY BEHIND EXITING SHORTWAVE ENERGY. COOLER AIR WILL RAP BACK IN AROUND THIS SYSTEM BY THURSDAY AND FRIDAY AS THE ENTIRE LONGWAVE TROUGH STRUCTURE SLOWLY WORKS EASTWARD ACROSS THE GREAT LAKES. MOIST CYCLONIC FLOW WITH A GOOD DIURNAL COMPONENT WILL LIKELY TRANSLATE INTO ADDITIONAL SHOWER DEVELOPMENT EACH DAY. THIS WILL FIRMLY HOLD TEMPERATURES BELOW NORMAL /50S/...LIKELY RIGHT INTO NEXT WEEKEND. MARINE... EASTERLY WINDS WILL FIRMLY TAKE HOLD TODAY AND TONIGHT AS HIGH PRESSURE EXITS TO THE EAST AND LOW PRESSURE ORGANIZES OUT WEST. THIS WILL BRING A CORRESPONDING INCREASE IN WAVES ACROSS NORTHERN AND CENTRAL LAKE HURON. WAVE HEIGHTS WILL REACH SMALL CRAFT CONDITIONS BY TONIGHT ACROSS OUTER SAGINAW BAY AND THE NEARSHORE WATERS ALONG THE THUMB. AN ADVISORY IS NOW IN PLACE FOR THESE LOCALES. EXPANSION OF ELEVATED WAVE HEIGHTS ARE EXPECTED OVER ALL NEARSHORE LOCATIONS BY MONDAY. GUSTY EASTERLY FLOW WILL PERSIST THROUGH TUESDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS FROM PORT AUSTIN TO HARBOR BEACH...FROM 2 AM MONDAY TO 10 PM TUESDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....BT SHORT TERM...CB LONG TERM....MR MARINE.......MR YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
750 AM EDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 515 AM EDT SUN APR 27 2014 WV IMAGERY AND RUC ANALYSIS SHOWS A NEG-TILT TROUGH OVER THE CENTRAL PLAINS WITH BUILDING 5H HGTS AND AMPLIFYING RDG OVER THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDING FROM HUDSON BAY INTO THE WRN GREAT LAKES RESULTED IN A DRY ERLY FLOW ACROSS UPPER MI EARLY THIS MORNING. IR SATELLITE ONLY REVEALS SOME BLOWOFF HIGH CLOUDS FM CONVECTION OVER THE DAKOTAS AND MN SPILLING INTO UPPER MI. TODAY INTO TONIGHT...MODELS INDICATE THE STRONG MID LEVEL LOW NEAR THE AZ/CO BORDER WILL LIFT NORTH INTO NEBRASKA LATE TONIGHT AS THE MID-LVL AND SFC LOW BECOME VERTICALLY STACKED. WAA PCPN LIFTING THROUGH MN AND NRN WI EARLY THIS MORNING AHEAD OF THE 850 MB WARM FRONT HAS BEEN BREAKING APART ON THE NRN EDGE AS IT ENCOUNTERS VERY DRY AIRMASS AND DRY ERLY FLOW CIRCULATING AROUND HUDSON BAY HIGH. DRYNESS OF AIRMASS IN PLACE OVER THE UPPER GREAT LAKES VERY EVIDENT FM 00Z KGRB AND KINL SNDGS. GIVEN DRY AIRMASS IN PLACE WILL LEAN TOWARD DRIER SOLN OF NAM AND REG GEM FOR OUR FCST AREA TODAY INTO TONIGHT OVER SOMEWHAT MORE AGGRESSIVE GFS SOLN. GENERALLY EXPECT THAT PCPN WILL STAY TO THE SOUTH OF THE CWA THROUGH TODAY WITH POSSIBLY SOME LIGHT MIXED PCPN (NO MORE THAN A COUPLE OF HUNDREDTHS OF AN INCH) FINALLY REACHING INTO THE FAR SW PORTION OF THE CWA TONIGHT. TEMPS WILL REMAIN BELOW NORMAL...WITH HIGHS TODAY RANGING FROM THE UPPER 30S/LOWER 40S ALONG GREAT LAKES IN E-NE FLOW TO MID 40S TO AROUND 50 FARTHER INLAND FROM THE GREAT LAKES. LOWS TONIGHT WILL BE IN THE LOWER TO MID 30S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 409 AM EDT SUN APR 27 2014 CHALLENGING LONG TERM IN SPITE OF GOOD MODEL TO MODEL AGREEMENT AND DECENT RUN TO RUN CONTINUITY. A VIGOROUS UPPER LEVEL SHORTWAVE CURRENTLY NEAR THE FOUR CORNERS WILL DEEPEN SIGNIFICANTLY AS IT MOVES INTO THE CENTRAL PLAINS. THE SYSTEM WILL BECOME OCCLUDED AND VERTICALLY STACKED BY 12Z MON WITH THE 986MB SFC LOW OVER NE. THE UPPER LOW WILL BROADEN AND WEAKEN WHILE BECOMING CENTERED NEAR IA BY 00Z WED...WITH THE SYSTEM AT THIS POINT BEING SANDWICHED BETWEEN A STOUT UPPER RIDGE OVER THE W COAST AND A SLIGHTLY WEAKER RIDGE EXTENDING UP THE E COAST AND CURVING BACK OVER HUDSON BAY. THE BLOCKING PATTERN WILL FORCE THE UPPER LOW TO HANG OUT OVER THE NCENTRAL CONUS THROUGH THE MIDDLE OF THIS WEEK WHILE SLOWLY FILLING. MULTIPLE SHORTWAVES WILL BE ROTATING AROUND THE LOW ACCORDING TO MODELS. ADDITIONAL UPPER LEVEL ENERGY WILL LATE IN THE WEEK INTO NEXT WEEKEND...ALLOWING FOR A FRESHENING OF THE PATTERN AND THE UPPER LOW TO EXIT THE REGION. AS PREVIOUSLY MENTIONED...MODELS AGREE WELL AT THIS TIME...BUT THIS SYSTEM WILL UNDERGO A LOT OF CHANGE IN THE NEXT 1-2 DAYS. IT WILL BE INTERESTING TO SEE HOW MODELED MASS FIELDS CHANGE AFTER A SIGNIFICANT SEVERE WEATHER EVENT UNFOLDS ACROSS THE SCENTRAL CONUS TODAY INTO MONDAY. MOST UNCERTAIN AND RIPE FOR CHANGE ARE DETAILS RELATED TO SHORTWAVE ENERGY PROGGED TO ROTATE THROUGH THE CWA A FEW TIMES THIS WEEK. OVERALL...WILL NOT GET TOO SPECIFIC WITH DETAILS YET AND WILL NOT CHANGE THE FORECAST MUCH /ESPECIALLY AFTER MON/. FOR MON...MOISTURE TRANSPORT WILL FOCUS INTO THE REGION ALONG AND BEHIND A WARM FRONT THAT MODELS SHOW STALLING NEAR OR OVER THE FAR SWRN CWA. THINK THAT MODELS ARE ON THE RIGHT TRACK SHOWING A TIGHT GRADIENT TO PRECIP /WHICH ALSO LINES UP WELL WITH PREVIOUS FORECAST/ DUE TO VERY DRY AIR /1000-700MB RH LESS THAN 30 PERCENT/ OVER THE NERN CWA AS A RESULT OF A HUDSON BAY HIGH OF 1050MB. THREW OUT THE NAM FOR THIS PERIOD AS IT WAS BY FAR THE FARTHEST SW WITH THE PRECIP AND OTHER MODELS WERE IN GOOD AGREEMENT IN BRINGING SOME PRECIP TO THE SWRN CWA. PRECIP SHOULD BE ALL RAIN ON MON. THE UPPER LOW MUST BE HUNGRY MON NIGHT BECAUSE MODELS SHOW THE LOW SUCKING IN A WEAK UPPER LOW FROM QUEBEC...FORMING AN UPPER TROUGH OVER THE WRN/NRN CWA MON NIGHT INTO TUE MORNING. COLDER AIR IS BROUGHT IN WITH THE WEAK LOW /IF THAT SCENARIO DOES PLAY OUT/...WHICH WOULD BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHER TERRAIN OF THE NWRN CWA. AT THE TIME SNOW WOULD BE FAVORED PRECIP WILL BE MINIMAL SO NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED. ANOTHER SLUG OF MOISTURE/RAIN COMES ON TUE AS MODELS CURRENTLY SHOW A SHORTWAVE MOVING ROTATING THROUGH THE REGION. THE TIMING COULD CHANGE...BUT GIVEN THAT MODELS CURRENTLY AGREE FAIRLY WELL ON THIS AND THAT THE FORECAST HAS LIKELY OR GREATER POPS...WILL NOT CHANGE THINGS SIGNIFICANTLY. MODELS INDICATE QPF ON TUE OF 0.25 INCHES OVER THE WRN CWA TO OVER A HALF INCH OVER THE ERN CWA. DRIER MID-UPPER LEVEL AIR MOVES IN ON TUE NIGHT...AND WITH LOW LEVEL MOISTURE STAYING PUT DRIZZLE MAY BE THE PRIMARY PRECIP TYPE TUE NIGHT. WILL NOT GET THAT SPECIFIC AT THIS POINT AND JUST CONTINUE TO CALL FOR SOME RAIN. THE UPPER LOW MOVES INTO THE CWA ON WED...BRINGING AN OCCLUDING SFC LOW INTO THE ERN CWA FROM THE S. THIS WOULD LEAD TO ANOTHER ROUND OF RAIN ON WED...ESPECIALLY IF A TROWAL SETS UP ON THE SW SIDE OF THE 850MB LOW /STACKED OVER THE SFC LOW/. AGAIN...LIKELY POPS IN THE PREVIOUS FORECAST LOOK REASONABLE GIVEN SOME UNCERTAINTY SO WILL NOT MAKE SIGNIFICANT CHANGES TO THAT. HAVE FORECASTED STORM TOTAL QPF FROM MONDAY THROUGH WED OF AROUND 1.00 INCHES OVER NRN UPPER MI TO 1.50-2.00 INCHES ALONG THE WI BORDER. WITH THE PATTERN CHANGING AS THE UPPER LOW WEAKENS AND MOVES OUT LATER IN THE WEEK...SIGNIFICANT PRECIP IS LESS LIKELY SO GOING CHANCE POPS IN THE PREVIOUS FORECAST SHOULD HANDLE THINGS WELL. WILL USE A CONSENSUS OF MODELS GUIDANCE DURING THIS PERIOD. COULD SEE A RETURN OF MIXED PRECIP AS COOLER AIR MAY MOVE IN FROM THE NW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 741 AM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS FROM THE WEST THIS AFTERNOON INTO THIS EVENING. THERE COULD BE SOME INTERMITTENT LIGHT RAIN AT KIWD BEGINNING THIS EVENING AS MID LEVELS BEGIN TO MOISTEN...BUT CONDITIONS WILL REMAIN VFR. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 515 AM EDT SUN APR 27 2014 EAST WINDS INCREASE TODAY INTO TONIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. EXPECT NE GALES TO 35KTS OVER WESTERN LK SUPERIOR TOWARD DULUTH BY LATE AFTERNOON CONTINUING INTO TUE MORNING. EAST GALES ARE THEN EXPECTED LATE TONIGHT INTO MON OVER THE REST OF THE WESTERN LAKE. WINDS WILL GRADUALLY DIMINISH TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 409 AM EDT SUN APR 27 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. WHILE THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION ARE NOT EXPECTED TO REACH FLOOD STAGE IN THE SHORT TERM...THE STURGEON RIVER NEAR CHASSELL REMAINS NEAR FLOOD STAGE AND IS EXPECTED TO REMAIN STEADY OR SLOWLY FALL INTO EARLY THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. A LARGE LOW PRESSURE SYSTEM WILL MOVE INTO THE GREAT LAKES BY THE MIDDLE OF THIS WEEK. PERIODS OF RAIN ARE POSSIBLE FROM LATE MONDAY THROUGH THURSDAY WITH THE POTENTIAL FOR TOTAL AMOUNTS AN INCH TO TWO INCHES. THIS WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS OVER THE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM EDT /4 PM CDT/ THIS AFTERNOON TO 11 AM EDT /10 AM CDT/ TUESDAY FOR LSZ162. GALE WARNING FROM 2 AM TO 8 PM EDT MONDAY FOR LSZ263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS MARINE...VOSS HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
710 AM EDT SUN APR 27 2014 .AVIATION... //DISCUSSION... THE ARRIVAL OF THE HIGH CLOUD ENDED THE REIGN OF THE LOWER TROPOSPHERIC STRATOCUMULUS THAT HAD BECOME A NUISANCE. RIDGING THROUGHOUT THE COLUMN WILL DOMINATE THE WEATHER TODAY LEADING TO ANOTHER DAY OF QUIET WEATHER. PLENTY OF HIGH CLOUD IS EXPECTED TO SPILL OVER THE RIDGE AXIS WHICH WILL KEEP A BKN CIG OF LITTLE TO NO IMPACT. TIMING OF PRECIPITATION FOR MONDAY REMAINS IN FLUX...ALTHOUGH THERE IS HIGH CONFIDENCE THAT RAINFALL WILL HOLD OFF UNTIL AFTER 12Z MONDAY MORNING. //DTW THRESHOLD THREATS... * AN EASTERLY WIND TRAJECTORY WILL HOLD THROUGHOUT VIRTUALLY ALL OF THE PERIOD. && .PREV DISCUSSION...ISSUED 403 AM EDT SUN APR 27 2014 SHORT TERM...TODAY AND TONIGHT SURFACE RIDGING IS IN PLACE THIS MORNING FROM JAMES BAY DOWN THROUGH THE LOWER PENINSULA OF MICHIGAN WITH THE LOW TO MIDLEVEL RIDGE AXIS RESIDING WELL WEST OF THE STATE. NOT SURPRISINGLY...THE WEATHER OVER SOUTHEASTERN MICHIGAN HAS BEEN VERY QUIET OVERNIGHT THANKS TO THE STABLE AIRMASS THAT IS IN RESIDENCE. THE LOW STRATOCUMULUS THAT PLAGUED THE NORTHERN CWA FOR MUCH OF TODAY...FORCED FROM COLD AIR ADVECTION....RAPIDLY DISSIPATED THE PAST COUPLE OF HOURS AS HIGH CLOUD SPILLING OVER THE MIDLEVEL RIDGE TRACKED OVERHEAD. THE LOSS OF CLOUD TOP COOLING SEEMED TO HAVE AN ALMOST INSTANTANEOUS IMPACT ON THE CLOUD. IT IS DIFFICULT TO COME UP WITH AN ACCURATE PORTRAYAL OF CLOUDS FOR THE DAYBREAK HOUR AS IT IS A TOUGH TASK TO GAIN SOME HANDLING ON THE OPACITY OF THE CLOUD. WITH THE BLOCKED NATURE OF THE FLOW/TROUGH AXIS REMAINING OVER MUCH OF THE CENTRAL PLAINS TODAY...FAVOR A MORE TRANSPARENT HIGH CLOUD AND WILL BE VERY OPTIMISTIC WITH THE SKY COVER FORECAST FOR TODAY. MODERATION OF THE AIR MASS OF SOME 4C AT 850MB BY THE AFTERNOON ALONG WITH THE IDEA OF MORE INSOLATION...DECIDED TO GO ON THE HIGH END OF GUIDANCE WITH SOME LOCATIONS OVERACHIEVING. HIGHS TODAY ARE EXPECTED TO REACH THE LOWER TO MIDDLE 50S. LOW DEWPOINTS AND CHILLY EASTERLY WIND TRAJECTORIES WILL KEEP SOME DENIZENS OF SOUTHEASTERN MICHIGAN UNSATISFIED FOR A SECOND DAY. THE MIDLEVEL RIDGE AXIS IS FORECASTED TO REMAIN WEST OF SOUTHEASTERN MICHIGAN THROUGH 12Z MONDAY. IN ADDITION...COLD NEAR SURFACE DRAINAGE FLOW IS EXPECTED OFF OF THE CANADIAN SURFACE HIGH. FOR THESE REASONS...REMOVED ALL MENTION OF PRECIPITATION FOR TONIGHT. COULD SEE SOME VIRGA APPROACH LENAWEE AND WASHTENAW COUNTIES AROUND 12Z...BUT FEEL THE POTENTIAL TO MEASURE A HUNDREDTH IS TOO LOW TO WARRANT A PRECIPITATION MENTION. LONG TERM... CUTOFF UPPER LOW POSITIONED OVER NEBRASKA BY MONDAY WILL REMAIN THE PREVALENT LARGE SCALE FEATURE THROUGHOUT THE UPCOMING WORK WEEK AS THE CIRCULATION/TROUGH UNGOES CONSIDERABLE EXPANSION IN SCALE. THE CIRCULATION CENTER AND ASSOCIATED MEAN TROUGH AXIS WILL ONLY SLOWLY MIGRATE EASTWARD WITH TIME...A POSITIONING THAT LEAVES SOUTHEAST MICHIGAN FIRMLY WITHIN THE EASTWARD FLANK OF THE LOWER HEIGHT FIELD DURING THE EARLY AND MIDWEEK PERIODS. DEEPENING DOWNSTREAM SOUTHWEST FLOW WILL INITIATE A STRONG LOW-MID LEVEL THETA-E AND WARM AIR ADVECTIVE RESPONSE TODAY AND TONIGHT...THE NET RESULT BEING A STEADY NORTHEASTWARD EXPANSION IN 850-925 MB ISENTROPIC ASCENT AS THE ELEVATED WARM FRONTAL SLOPE WORKS INTO SOUTHEAST MICHIGAN MONDAY AND MONDAY NIGHT. THERE REMAINS SOME UNCERTAINTY YET IN HOW QUICKLY THIS PROCESS UNFOLDS AND TRANSLATES NORTHWARD THROUGH THE DAYLIGHT HOURS ON MONDAY...OWING TO THE OVERALL DEPTH OF THE EXISTING DRY LAYER RETAINED WITH THE SURFACE-925 MB EASTERLY GRADIENT. THIS PARTICULAR PATTERN OFTEN FAVORS A SLOWER EVOLUTION...SUPPORTING THAT OF THE ECMWF/NAM IN PROVIDING A MORE INCREMENTAL RAMP UP OF POPS FROM SOUTH TO NORTH...THE TRI-CITIES/THUMB LARGELY SEEING A DRY START TO THE WEEK. LARGE SCALE ASCENT WILL BE AUGMENTED BY BOTH FAVORABLE EXIT REGION JET DYNAMICS AND SOME FORM OF WEAK CVA AS SHREDS OF MID LEVEL ENERGY WORK THROUGH THE UPSTREAM CIRCULATION. THIS WILL SUPPORT A HIGHER END COVERAGE OF SHOWERS /CONTAINING A FEW RUMBLES OF THUNDER/ BY LATE MONDAY INTO MONDAY NIGHT. QPF POTENTIAL IN THE HALF INCH RANGE WITH THIS FIRST EPISODE OF PRECIPITATION. THE SUBSTANTIAL CLOUD COVER AND INCREASING PROSPECTS FOR SHOWERS WITHIN AN EASTERLY FLOW WILL LOCK TEMPERATURES WITHIN THE LOWER TO MIDDLE 50S AREAWIDE. LARGER SCALE PATTERN WILL CONTINUE TO SUPPORT ADDITIONAL ROUNDS OF SHOWERS WITHIN THE TUESDAY AND WEDNESDAY PERIODS...THE DETAILS SENSITIVE TO PROPER PLACEMENT OF THE GOVERNING BACKGROUND DYNAMICS TIED ADDITIONAL SHORTWAVE ENERGY LODGED IN THE BROADER CYCLONIC FLOW. 00Z MODEL GUIDANCE WOULD SUGGEST THE SURFACE WARM FRONT WILL SHIFT THROUGH ON TUESDAY...PERHAPS PROVIDING A LOW LEVEL ANCHOR POINT FOR ADDITIONAL DEVELOPMENT GIVEN AN ADDED DIURNAL COMPONENT AND CONTINUED FAVORED PLACEMENT OF THE ATTENDANT UPPER JET STREAK. STILL THE POTENTIAL FOR TEMPERATURES TO MAKE A LATE RUN POST- FRONTALLY INTO THE MIDDLE AND UPPER 60S ON TUESDAY. HIGHER END POPS REMAIN WARRANTED THROUGH WEDNESDAY GIVEN THE PATTERN PERSISTENCE...ALTHOUGH THERE MAY BE A NOTEWORTHY BREAK IN ACTIVITY AT SOME POINT WITHIN ANY POCKETS OF MID LEVEL SUBSIDENCE THAT CAN FILL IN IMMEDIATELY BEHIND EXITING SHORTWAVE ENERGY. COOLER AIR WILL RAP BACK IN AROUND THIS SYSTEM BY THURSDAY AND FRIDAY AS THE ENTIRE LONGWAVE TROUGH STRUCTURE SLOWLY WORKS EASTWARD ACROSS THE GREAT LAKES. MOIST CYCLONIC FLOW WITH A GOOD DIURNAL COMPONENT WILL LIKELY TRANSLATE INTO ADDITIONAL SHOWER DEVELOPMENT EACH DAY. THIS WILL FIRMLY HOLD TEMPERATURES BELOW NORMAL /50S/...LIKELY RIGHT INTO NEXT WEEKEND. MARINE... EASTERLY WINDS WILL FIRMLY TAKE HOLD TODAY AND TONIGHT AS HIGH PRESSURE EXITS TO THE EAST AND LOW PRESSURE ORGANIZES OUT WEST. THIS WILL BRING A CORRESPONDING INCREASE IN WAVES ACROSS NORTHERN AND CENTRAL LAKE HURON. WAVE HEIGHTS WILL REACH SMALL CRAFT CONDITIONS BY TONIGHT ACROSS OUTER SAGINAW BAY AND THE NEARSHORE WATERS ALONG THE THUMB. AN ADVISORY IS NOW IN PLACE FOR THESE LOCALES. EXPANSION OF ELEVATED WAVE HEIGHTS ARE EXPECTED OVER ALL NEARSHORE LOCATIONS BY MONDAY. GUSTY EASTERLY FLOW WILL PERSIST THROUGH TUESDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS FROM PORT AUSTIN TO HARBOR BEACH...FROM 2 AM MONDAY TO 10 PM TUESDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....CB SHORT TERM...CB LONG TERM....MR MARINE.......MR YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
517 AM EDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 515 AM EDT SUN APR 27 2014 WV IMAGERY AND RUC ANALYSIS SHOWS A NEG-TILT TROUGH OVER THE CENTRAL PLAINS WITH BUILDING 5H HGTS AND AMPLIFYING RDG OVER THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDING FROM HUDSON BAY INTO THE WRN GREAT LAKES RESULTED IN A DRY ERLY FLOW ACROSS UPPER MI EARLY THIS MORNING. IR SATELLITE ONLY REVEALS SOME BLOWOFF HIGH CLOUDS FM CONVECTION OVER THE DAKOTAS AND MN SPILLING INTO UPPER MI. TODAY INTO TONIGHT...MODELS INDICATE THE STRONG MID LEVEL LOW NEAR THE AZ/CO BORDER WILL LIFT NORTH INTO NEBRASKA LATE TONIGHT AS THE MID-LVL AND SFC LOW BECOME VERTICALLY STACKED. WAA PCPN LIFTING THROUGH MN AND NRN WI EARLY THIS MORNING AHEAD OF THE 850 MB WARM FRONT HAS BEEN BREAKING APART ON THE NRN EDGE AS IT ENCOUNTERS VERY DRY AIRMASS AND DRY ERLY FLOW CIRCULATING AROUND HUDSON BAY HIGH. DRYNESS OF AIRMASS IN PLACE OVER THE UPPER GREAT LAKES VERY EVIDENT FM 00Z KGRB AND KINL SNDGS. GIVEN DRY AIRMASS IN PLACE WILL LEAN TOWARD DRIER SOLN OF NAM AND REG GEM FOR OUR FCST AREA TODAY INTO TONIGHT OVER SOMEWHAT MORE AGGRESSIVE GFS SOLN. GENERALLY EXPECT THAT PCPN WILL STAY TO THE SOUTH OF THE CWA THROUGH TODAY WITH POSSIBLY SOME LIGHT MIXED PCPN (NO MORE THAN A COUPLE OF HUNDREDTHS OF AN INCH) FINALLY REACHING INTO THE FAR SW PORTION OF THE CWA TONIGHT. TEMPS WILL REMAIN BELOW NORMAL...WITH HIGHS TODAY RANGING FROM THE UPPER 30S/LOWER 40S ALONG GREAT LAKES IN E-NE FLOW TO MID 40S TO AROUND 50 FARTHER INLAND FROM THE GREAT LAKES. LOWS TONIGHT WILL BE IN THE LOWER TO MID 30S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 409 AM EDT SUN APR 27 2014 CHALLENGING LONG TERM IN SPITE OF GOOD MODEL TO MODEL AGREEMENT AND DECENT RUN TO RUN CONTINUITY. A VIGOROUS UPPER LEVEL SHORTWAVE CURRENTLY NEAR THE FOUR CORNERS WILL DEEPEN SIGNIFICANTLY AS IT MOVES INTO THE CENTRAL PLAINS. THE SYSTEM WILL BECOME OCCLUDED AND VERTICALLY STACKED BY 12Z MON WITH THE 986MB SFC LOW OVER NE. THE UPPER LOW WILL BROADEN AND WEAKEN WHILE BECOMING CENTERED NEAR IA BY 00Z WED...WITH THE SYSTEM AT THIS POINT BEING SANDWICHED BETWEEN A STOUT UPPER RIDGE OVER THE W COAST AND A SLIGHTLY WEAKER RIDGE EXTENDING UP THE E COAST AND CURVING BACK OVER HUDSON BAY. THE BLOCKING PATTERN WILL FORCE THE UPPER LOW TO HANG OUT OVER THE NCENTRAL CONUS THROUGH THE MIDDLE OF THIS WEEK WHILE SLOWLY FILLING. MULTIPLE SHORTWAVES WILL BE ROTATING AROUND THE LOW ACCORDING TO MODELS. ADDITIONAL UPPER LEVEL ENERGY WILL LATE IN THE WEEK INTO NEXT WEEKEND...ALLOWING FOR A FRESHENING OF THE PATTERN AND THE UPPER LOW TO EXIT THE REGION. AS PREVIOUSLY MENTIONED...MODELS AGREE WELL AT THIS TIME...BUT THIS SYSTEM WILL UNDERGO A LOT OF CHANGE IN THE NEXT 1-2 DAYS. IT WILL BE INTERESTING TO SEE HOW MODELED MASS FIELDS CHANGE AFTER A SIGNIFICANT SEVERE WEATHER EVENT UNFOLDS ACROSS THE SCENTRAL CONUS TODAY INTO MONDAY. MOST UNCERTAIN AND RIPE FOR CHANGE ARE DETAILS RELATED TO SHORTWAVE ENERGY PROGGED TO ROTATE THROUGH THE CWA A FEW TIMES THIS WEEK. OVERALL...WILL NOT GET TOO SPECIFIC WITH DETAILS YET AND WILL NOT CHANGE THE FORECAST MUCH /ESPECIALLY AFTER MON/. FOR MON...MOISTURE TRANSPORT WILL FOCUS INTO THE REGION ALONG AND BEHIND A WARM FRONT THAT MODELS SHOW STALLING NEAR OR OVER THE FAR SWRN CWA. THINK THAT MODELS ARE ON THE RIGHT TRACK SHOWING A TIGHT GRADIENT TO PRECIP /WHICH ALSO LINES UP WELL WITH PREVIOUS FORECAST/ DUE TO VERY DRY AIR /1000-700MB RH LESS THAN 30 PERCENT/ OVER THE NERN CWA AS A RESULT OF A HUDSON BAY HIGH OF 1050MB. THREW OUT THE NAM FOR THIS PERIOD AS IT WAS BY FAR THE FARTHEST SW WITH THE PRECIP AND OTHER MODELS WERE IN GOOD AGREEMENT IN BRINGING SOME PRECIP TO THE SWRN CWA. PRECIP SHOULD BE ALL RAIN ON MON. THE UPPER LOW MUST BE HUNGRY MON NIGHT BECAUSE MODELS SHOW THE LOW SUCKING IN A WEAK UPPER LOW FROM QUEBEC...FORMING AN UPPER TROUGH OVER THE WRN/NRN CWA MON NIGHT INTO TUE MORNING. COLDER AIR IS BROUGHT IN WITH THE WEAK LOW /IF THAT SCENARIO DOES PLAY OUT/...WHICH WOULD BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHER TERRAIN OF THE NWRN CWA. AT THE TIME SNOW WOULD BE FAVORED PRECIP WILL BE MINIMAL SO NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED. ANOTHER SLUG OF MOISTURE/RAIN COMES ON TUE AS MODELS CURRENTLY SHOW A SHORTWAVE MOVING ROTATING THROUGH THE REGION. THE TIMING COULD CHANGE...BUT GIVEN THAT MODELS CURRENTLY AGREE FAIRLY WELL ON THIS AND THAT THE FORECAST HAS LIKELY OR GREATER POPS...WILL NOT CHANGE THINGS SIGNIFICANTLY. MODELS INDICATE QPF ON TUE OF 0.25 INCHES OVER THE WRN CWA TO OVER A HALF INCH OVER THE ERN CWA. DRIER MID-UPPER LEVEL AIR MOVES IN ON TUE NIGHT...AND WITH LOW LEVEL MOISTURE STAYING PUT DRIZZLE MAY BE THE PRIMARY PRECIP TYPE TUE NIGHT. WILL NOT GET THAT SPECIFIC AT THIS POINT AND JUST CONTINUE TO CALL FOR SOME RAIN. THE UPPER LOW MOVES INTO THE CWA ON WED...BRINGING AN OCCLUDING SFC LOW INTO THE ERN CWA FROM THE S. THIS WOULD LEAD TO ANOTHER ROUND OF RAIN ON WED...ESPECIALLY IF A TROWAL SETS UP ON THE SW SIDE OF THE 850MB LOW /STACKED OVER THE SFC LOW/. AGAIN...LIKELY POPS IN THE PREVIOUS FORECAST LOOK REASONABLE GIVEN SOME UNCERTAINTY SO WILL NOT MAKE SIGNIFICANT CHANGES TO THAT. HAVE FORECASTED STORM TOTAL QPF FROM MONDAY THROUGH WED OF AROUND 1.00 INCHES OVER NRN UPPER MI TO 1.50-2.00 INCHES ALONG THE WI BORDER. WITH THE PATTERN CHANGING AS THE UPPER LOW WEAKENS AND MOVES OUT LATER IN THE WEEK...SIGNIFICANT PRECIP IS LESS LIKELY SO GOING CHANCE POPS IN THE PREVIOUS FORECAST SHOULD HANDLE THINGS WELL. WILL USE A CONSENSUS OF MODELS GUIDANCE DURING THIS PERIOD. COULD SEE A RETURN OF MIXED PRECIP AS COOLER AIR MAY MOVE IN FROM THE NW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 125 AM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS TOWARDS THE END OF THE PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 515 AM EDT SUN APR 27 2014 EAST WINDS INCREASE TODAY INTO TONIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. EXPECT NE GALES TO 35KTS OVER WESTERN LK SUPERIOR TOWARD DULUTH BY LATE AFTERNOON CONTINUING INTO TUE MORNING. EAST GALES ARE THEN EXPECTED LATE TONIGHT INTO MON OVER THE REST OF THE WESTERN LAKE. WINDS WILL GRADUALLY DIMINISH TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 409 AM EDT SUN APR 27 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. WHILE THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION ARE NOT EXPECTED TO REACH FLOOD STAGE IN THE SHORT TERM...THE STURGEON RIVER NEAR CHASSELL REMAINS NEAR FLOOD STAGE AND IS EXPECTED TO REMAIN STEADY OR SLOWLY FALL INTO EARLY THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. A LARGE LOW PRESSURE SYSTEM WILL MOVE INTO THE GREAT LAKES BY THE MIDDLE OF THIS WEEK. PERIODS OF RAIN ARE POSSIBLE FROM LATE MONDAY THROUGH THURSDAY WITH THE POTENTIAL FOR TOTAL AMOUNTS AN INCH TO TWO INCHES. THIS WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS OVER THE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM EDT /4 PM CDT/ THIS AFTERNOON TO 11 AM EDT /10 AM CDT/ TUESDAY FOR LSZ162. GALE WARNING FROM 2 AM TO 8 PM EDT MONDAY FOR LSZ263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...07 MARINE...VOSS HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
412 AM EDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 417 PM EDT SAT APR 26 2014 WV IMAGERY AND RUC ANALYSIS INDICATED CONFLUENT MID/UPPER LEVEL FLOW THROUGH THE NRN LAKES BETWEEN A TROUGH INTO THE NE CONUS AND A RIDGE FROM THE MID MS VALLEY INTO THE NRN PLAINS SASK. AT THE SFC...A RIDGE EXTENDED FROM HUDSON BAY INTO THE WRN GREAT LAKES RESULTING IN N TO NE FLOW INTO UPPER MICHIGAN. VIS LOOP SHOWED A CLEARING TREND WITH THE COMBINATION OF DRY ADVECTION AND DAYTIME MIXING HELPING TO SCOUR OUT THE LOW CLOUDS. AFTERNOON TEMPS RANGED FROM THE MID 30S NORTH...DOWNWIND OF LAKE SUPERIOR...TO THE MID 40S OVER THE SOUTH. TONIGHT...EVEN THOUGH THERE MAY BE SOME INCREASE IN HIGH CLOUDS OVERNIGHT AND SOME LIGHT EAST WINDS...EXPECT RADIATIONAL COOLING CONDITIONS WILL BE FAVORABLE ENOUGH TO ALLOW TEMPS TO DROP TOWARD THE LOWER 20S INLAND NORTH AND TO AROUND 30 NEAR THE WI BORDER. SUN...AS THE STRONG MID LEVEL AND SFC LOW MOVE INTO THE CNTRL PLAINS WAA PCPN AHEAD OF THE 850 MB WARM FRONT MAY APPROACH UPPER MI AS IT SPREADS THROUGH WI. HOWEVER...WITH PERSISTENT ERLY LOW LEVEL DRY ADVECTION AND THE VERY DRY PROFILE BELOW 750 MB...PER FCST SOUNDINGS...EXPECT THAT THE PCPN WILL STAY TO THE SOUTH OF THE CWA. TEMPS WILL REMAIN BELOW NORMAL...WITH HIGHS IN THE MID 40S TO AROUND 50 OVER MUCH OF UPPER MICHIGAN. HOWEVER...OVER N CNTRL UPPER MI AND THE KEWEENAW...THE EAST WIND OFF OF LAKE SUPERIOR WILL KEEP HIGHS FROM AROUND 40 TO 45. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 409 AM EDT SUN APR 27 2014 CHALLENGING LONG TERM IN SPITE OF GOOD MODEL TO MODEL AGREEMENT AND DECENT RUN TO RUN CONTINUITY. A VIGOROUS UPPER LEVEL SHORTWAVE CURRENTLY NEAR THE FOUR CORNERS WILL DEEPEN SIGNIFICANTLY AS IT MOVES INTO THE CENTRAL PLAINS. THE SYSTEM WILL BECOME OCCLUDED AND VERTICALLY STACKED BY 12Z MON WITH THE 986MB SFC LOW OVER NE. THE UPPER LOW WILL BROADEN AND WEAKEN WHILE BECOMING CENTERED NEAR IA BY 00Z WED...WITH THE SYSTEM AT THIS POINT BEING SANDWICHED BETWEEN A STOUT UPPER RIDGE OVER THE W COAST AND A SLIGHTLY WEAKER RIDGE EXTENDING UP THE E COAST AND CURVING BACK OVER HUDSON BAY. THE BLOCKING PATTERN WILL FORCE THE UPPER LOW TO HANG OUT OVER THE NCENTRAL CONUS THROUGH THE MIDDLE OF THIS WEEK WHILE SLOWLY FILLING. MULTIPLE SHORTWAVES WILL BE ROTATING AROUND THE LOW ACCORDING TO MODELS. ADDITIONAL UPPER LEVEL ENERGY WILL LATE IN THE WEEK INTO NEXT WEEKEND...ALLOWING FOR A FRESHENING OF THE PATTERN AND THE UPPER LOW TO EXIT THE REGION. AS PREVIOUSLY MENTIONED...MODELS AGREE WELL AT THIS TIME...BUT THIS SYSTEM WILL UNDERGO A LOT OF CHANGE IN THE NEXT 1-2 DAYS. IT WILL BE INTERESTING TO SEE HOW MODELED MASS FIELDS CHANGE AFTER A SIGNIFICANT SEVERE WEATHER EVENT UNFOLDS ACROSS THE SCENTRAL CONUS TODAY INTO MONDAY. MOST UNCERTAIN AND RIPE FOR CHANGE ARE DETAILS RELATED TO SHORTWAVE ENERGY PROGGED TO ROTATE THROUGH THE CWA A FEW TIMES THIS WEEK. OVERALL...WILL NOT GET TOO SPECIFIC WITH DETAILS YET AND WILL NOT CHANGE THE FORECAST MUCH /ESPECIALLY AFTER MON/. FOR MON...MOISTURE TRANSPORT WILL FOCUS INTO THE REGION ALONG AND BEHIND A WARM FRONT THAT MODELS SHOW STALLING NEAR OR OVER THE FAR SWRN CWA. THINK THAT MODELS ARE ON THE RIGHT TRACK SHOWING A TIGHT GRADIENT TO PRECIP /WHICH ALSO LINES UP WELL WITH PREVIOUS FORECAST/ DUE TO VERY DRY AIR /1000-700MB RH LESS THAN 30 PERCENT/ OVER THE NERN CWA AS A RESULT OF A HUDSON BAY HIGH OF 1050MB. THREW OUT THE NAM FOR THIS PERIOD AS IT WAS BY FAR THE FARTHEST SW WITH THE PRECIP AND OTHER MODELS WERE IN GOOD AGREEMENT IN BRINGING SOME PRECIP TO THE SWRN CWA. PRECIP SHOULD BE ALL RAIN ON MON. THE UPPER LOW MUST BE HUNGRY MON NIGHT BECAUSE MODELS SHOW THE LOW SUCKING IN A WEAK UPPER LOW FROM QUEBEC...FORMING AN UPPER TROUGH OVER THE WRN/NRN CWA MON NIGHT INTO TUE MORNING. COLDER AIR IS BROUGHT IN WITH THE WEAK LOW /IF THAT SCENARIO DOES PLAY OUT/...WHICH WOULD BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHER TERRAIN OF THE NWRN CWA. AT THE TIME SNOW WOULD BE FAVORED PRECIP WILL BE MINIMAL SO NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED. ANOTHER SLUG OF MOISTURE/RAIN COMES ON TUE AS MODELS CURRENTLY SHOW A SHORTWAVE MOVING ROTATING THROUGH THE REGION. THE TIMING COULD CHANGE...BUT GIVEN THAT MODELS CURRENTLY AGREE FAIRLY WELL ON THIS AND THAT THE FORECAST HAS LIKELY OR GREATER POPS...WILL NOT CHANGE THINGS SIGNIFICANTLY. MODELS INDICATE QPF ON TUE OF 0.25 INCHES OVER THE WRN CWA TO OVER A HALF INCH OVER THE ERN CWA. DRIER MID-UPPER LEVEL AIR MOVES IN ON TUE NIGHT...AND WITH LOW LEVEL MOISTURE STAYING PUT DRIZZLE MAY BE THE PRIMARY PRECIP TYPE TUE NIGHT. WILL NOT GET THAT SPECIFIC AT THIS POINT AND JUST CONTINUE TO CALL FOR SOME RAIN. THE UPPER LOW MOVES INTO THE CWA ON WED...BRINGING AN OCCLUDING SFC LOW INTO THE ERN CWA FROM THE S. THIS WOULD LEAD TO ANOTHER ROUND OF RAIN ON WED...ESPECIALLY IF A TROWAL SETS UP ON THE SW SIDE OF THE 850MB LOW /STACKED OVER THE SFC LOW/. AGAIN...LIKELY POPS IN THE PREVIOUS FORECAST LOOK REASONABLE GIVEN SOME UNCERTAINTY SO WILL NOT MAKE SIGNIFICANT CHANGES TO THAT. HAVE FORECASTED STORM TOTAL QPF FROM MONDAY THROUGH WED OF AROUND 1.00 INCHES OVER NRN UPPER MI TO 1.50-2.00 INCHES ALONG THE WI BORDER. WITH THE PATTERN CHANGING AS THE UPPER LOW WEAKENS AND MOVES OUT LATER IN THE WEEK...SIGNIFICANT PRECIP IS LESS LIKELY SO GOING CHANCE POPS IN THE PREVIOUS FORECAST SHOULD HANDLE THINGS WELL. WILL USE A CONSENSUS OF MODELS GUIDANCE DURING THIS PERIOD. COULD SEE A RETURN OF MIXED PRECIP AS COOLER AIR MAY MOVE IN FROM THE NW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 125 AM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS TOWARDS THE END OF THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 PM EDT SAT APR 26 2014 EAST WINDS INCREASE ON SUNDAY INTO SUNDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. GUSTS COULD REACH GALE FORCE TO 35KTS OVER FAR WESTERN LK SUPERIOR TOWARD DULUTH BY LATE AFTERNOON. EAST GALES ARE THEN EXPECTED SUN NIGHT INTO MON OVER THE WEST. WINDS WILL GRADUALLY DIMINISH MON NIGHT INTO TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 409 AM EDT SUN APR 27 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. WHILE THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION ARE NOT EXPECTED TO REACH FLOOD STAGE IN THE SHORT TERM...THE STURGEON RIVER NEAR CHASSELL REMAINS NEAR FLOOD STAGE AND IS EXPECTED TO REMAIN STEADY OR SLOWLY FALL INTO EARLY THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. A LARGE LOW PRESSURE SYSTEM WILL MOVE INTO THE GREAT LAKES BY THE MIDDLE OF THIS WEEK. PERIODS OF RAIN ARE POSSIBLE FROM LATE MONDAY THROUGH THURSDAY WITH THE POTENTIAL FOR TOTAL AMOUNTS AN INCH TO TWO INCHES. THIS WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS OVER THE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM EDT /4 PM CDT/ THIS AFTERNOON TO 11 AM EDT /10 AM CDT/ TUESDAY FOR LSZ162. GALE WARNING FROM 2 AM TO 8 PM EDT MONDAY FOR LSZ263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
403 AM EDT SUN APR 27 2014 .SHORT TERM...TODAY AND TONIGHT SURFACE RIDGING IS IN PLACE THIS MORNING FROM JAMES BAY DOWN THROUGH THE LOWER PENINSULA OF MICHIGAN WITH THE LOW TO MIDLEVEL RIDGE AXIS RESIDING WELL WEST OF THE STATE. NOT SURPRISINGLY...THE WEATHER OVER SOUTHEASTERN MICHIGAN HAS BEEN VERY QUIET OVERNIGHT THANKS TO THE STABLE AIRMASS THAT IS IN RESIDENCE. THE LOW STRATOCUMULUS THAT PLAGUED THE NORTHERN CWA FOR MUCH OF TODAY...FORCED FROM COLD AIR ADVECTION....RAPIDLY DISSIPATED THE PAST COUPLE OF HOURS AS HIGH CLOUD SPILLING OVER THE MIDLEVEL RIDGE TRACKED OVERHEAD. THE LOSS OF CLOUD TOP COOLING SEEMED TO HAVE AN ALMOST INSTANTANEOUS IMPACT ON THE CLOUD. IT IS DIFFICULT TO COME UP WITH AN ACCURATE PORTRAYAL OF CLOUDS FOR THE DAYBREAK HOUR AS IT IS A TOUGH TASK TO GAIN SOME HANDLING ON THE OPACITY OF THE CLOUD. WITH THE BLOCKED NATURE OF THE FLOW/TROUGH AXIS REMAINING OVER MUCH OF THE CENTRAL PLAINS TODAY...FAVOR A MORE TRANSPARENT HIGH CLOUD AND WILL BE VERY OPTIMISTIC WITH THE SKY COVER FORECAST FOR TODAY. MODERATION OF THE AIR MASS OF SOME 4C AT 850MB BY THE AFTERNOON ALONG WITH THE IDEA OF MORE INSOLATION...DECIDED TO GO ON THE HIGH END OF GUIDANCE WITH SOME LOCATIONS OVERACHIEVING. HIGHS TODAY ARE EXPECTED TO REACH THE LOWER TO MIDDLE 50S. LOW DEWPOINTS AND CHILLY EASTERLY WIND TRAJECTORIES WILL KEEP SOME DENIZENS OF SOUTHEASTERN MICHIGAN UNSATISFIED FOR A SECOND DAY. THE MIDLEVEL RIDGE AXIS IS FORECASTED TO REMAIN WEST OF SOUTHEASTERN MICHIGAN THROUGH 12Z MONDAY. IN ADDITION...COLD NEAR SURFACE DRAINAGE FLOW IS EXPECTED OFF OF THE CANADIAN SURFACE HIGH. FOR THESE REASONS...REMOVED ALL MENTION OF PRECIPITATION FOR TONIGHT. COULD SEE SOME VIRGA APPROACH LENAWEE AND WASHTENAW COUNTIES AROUND 12Z...BUT FEEL THE POTENTIAL TO MEASURE A HUNDREDTH IS TOO LOW TO WARRANT A PRECIPITATION MENTION. && .LONG TERM... CUTOFF UPPER LOW POSITIONED OVER NEBRASKA BY MONDAY WILL REMAIN THE PREVALENT LARGE SCALE FEATURE THROUGHOUT THE UPCOMING WORK WEEK AS THE CIRCULATION/TROUGH UNGOES CONSIDERABLE EXPANSION IN SCALE. THE CIRCULATION CENTER AND ASSOCIATED MEAN TROUGH AXIS WILL ONLY SLOWLY MIGRATE EASTWARD WITH TIME...A POSITIONING THAT LEAVES SOUTHEAST MICHIGAN FIRMLY WITHIN THE EASTWARD FLANK OF THE LOWER HEIGHT FIELD DURING THE EARLY AND MIDWEEK PERIODS. DEEPENING DOWNSTREAM SOUTHWEST FLOW WILL INITIATE A STRONG LOW-MID LEVEL THETA-E AND WARM AIR ADVECTIVE RESPONSE TODAY AND TONIGHT...THE NET RESULT BEING A STEADY NORTHEASTWARD EXPANSION IN 850-925 MB ISENTROPIC ASCENT AS THE ELEVATED WARM FRONTAL SLOPE WORKS INTO SOUTHEAST MICHIGAN MONDAY AND MONDAY NIGHT. THERE REMAINS SOME UNCERTAINTY YET IN HOW QUICKLY THIS PROCESS UNFOLDS AND TRANSLATES NORTHWARD THROUGH THE DAYLIGHT HOURS ON MONDAY...OWING TO THE OVERALL DEPTH OF EXISTING DRY LAYER RETAINED WITH THE SURFACE-925 MB EASTERLY GRADIENT. THIS PARTICULAR PATTERN OFTEN FAVORS A SLOWER EVOLUTION...SUPPORTING THAT OF THE ECMWF/NAM IN PROVIDING A MORE INCREMENTAL RAMP UP OF POPS FROM SOUTH TO NORTH...THE TRI-CITIES/THUMB LARGELY SEEING A DRY START TO THE WEEK. LARGE SCALE ASCENT WILL BE AUGMENTED BY BOTH FAVORABLE EXIT REGION JET DYNAMICS AND SOME FORM OF WEAK CVA AS SHREDS OF MID LEVEL ENERGY WORK THROUGH THE UPSTREAM CIRCULATION. THIS WILL SUPPORT A HIGHER END COVERAGE OF SHOWERS /CONTAINING A FEW RUMBLES OF THUNDER/ BY LATE MONDAY INTO MONDAY NIGHT. QPF POTENTIAL IN THE HALF INCH RANGE WITH THIS FIRST EPISODE OF PRECIPITATION. THE SUBSTANTIAL CLOUD COVER AND INCREASING PROSPECTS FOR SHOWERS WITHIN AN EASTERLY FLOW WILL LOCK TEMPERATURES WITHIN THE LOWER TO MIDDLE 50S AREAWIDE. LARGER SCALE PATTERN WILL CONTINUE TO SUPPORT ADDITIONAL ROUNDS OF SHOWERS WITHIN TUESDAY AND WEDNESDAY PERIODS...THE DETAILS SENSITIVE TO PROPER PLACEMENT OF THE GOVERNING BACKGROUND DYNAMICS TIED ADDITIONAL SHORTWAVE ENERGY LODGED IN THE BROADER CYCLONIC FLOW. 00Z MODEL GUIDANCE WOULD SUGGEST THE SURFACE WARM FRONT WILL SHIFT THROUGH ON TUESDAY...PERHAPS PROVIDING A LOW LEVEL ANCHOR POINT FOR ADDITIONAL DEVELOPMENT GIVEN AN ADDED DIURNAL COMPONENT AND CONTINUED FAVORED PLACEMENT OF THE ATTENDANT UPPER JET STREAK. STILL THE POTENTIAL FOR TEMPERATURES TO MAKE A LATE RUN POST-FRONTALLY INTO THE MIDDLE AND UPPER 60S ON TUESDAY. HIGHER END POPS REMAIN WARRANTED THROUGH WEDNESDAY GIVEN THE PATTERN PERSISTENCE...ALTHOUGH THERE MAY BE A NOTEWORTHY BREAK IN ACTIVITY AT SOME POINT WITHIN ANY POCKETS OF MID LEVEL SUBSIDENCE THAT CAN FILL IN IMMEDIATELY BEHIND EXITING SHORTWAVE ENERGY. COOLER AIR WILL RAP BACK IN AROUND THIS SYSTEM BY THURSDAY AND FRIDAY AS THE ENTIRE LONGWAVE TROUGH STRUCTURE SLOWLY WORKS EASTWARD ACROSS THE GREAT LAKES. MOIST CYCLONIC FLOW WITH A GOOD DIURNAL COMPONENT WILL LIKELY TRANSLATE INTO ADDITIONAL SHOWER DEVELOPMENT EACH DAY. THIS WILL FIRMLY HOLD TEMPERATURES BELOW NORMAL /50S/...LIKELY RIGHT INTO NEXT WEEK. && .MARINE... EASTERLY WINDS WILL FIRMLY TAKE HOLD TODAY AND TONIGHT AS HIGH PRESSURE EXITS TO THE EAST AND LOW PRESSURE ORGANIZES OUT WEST. THIS WILL BRING A CORRESPONDING INCREASE IN WAVES ACROSS NORTHERN AND CENTRAL LAKE HURON. WAVE HEIGHTS WILL REACH SMALL CRAFT CONDITIONS BY TONIGHT ACROSS OUTER SAGINAW BAY AND THE NEARSHORE WATERS ALONG THE THUMB. AN ADVISORY IS NOW IN PLACE FOR THESE LOCALES. EXPANSION OF ELEVATED WAVE HEIGHTS ARE EXPECTED OVER ALL NEARSHORE LOCATIONS BY MONDAY. GUSTY EASTERLY FLOW WILL PERSIST THROUGH TUESDAY. && .AVIATION...ISSUED 1156 PM EDT SAT APR 26 2014 //DISCUSSION... THE PATCH OF VFR STRATUS OVER FNT AND MBS CONTINUES TO BE SLOWLY ERODED BY RIDGING AND DRIER AIR ADVECTING IN ON NORTHEAST FLOW. THE MAIN CONCERN IS UPSTREAM CLOUDS COULD BRING A REINFORCING SHOT OF CLOUD COVER TO THESE SITES OVERNIGHT...HOWEVER WILL CONTINUE A GENERAL CLEARING TREND OVER THE NEXT FEW HOURS. THICKENING HIGH CLOUDS WILL CONTINUE OVERNIGHT AND INTO SUNDAY MORNING AS LOW PRESSURE DEVELOPS OVER THE PLAINS. EASTERLY WINDS AROUND 10 KNOTS ARE EXPECTED DURING THE DAYTIME HOURS ON SUNDAY. //DTW THRESHOLD THREATS... * NONE. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS FROM PORT AUSTIN TO HARBOR BEACH...FROM 2 AM MONDAY TO 10 PM TUESDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...CB LONG TERM....MR MARINE.......MR AVIATION.....KURIMSKI YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
127 AM EDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 417 PM EDT SAT APR 26 2014 WV IMAGERY AND RUC ANALYSIS INDICATED CONFLUENT MID/UPPER LEVEL FLOW THROUGH THE NRN LAKES BETWEEN A TROUGH INTO THE NE CONUS AND A RIDGE FROM THE MID MS VALLEY INTO THE NRN PLAINS SASK. AT THE SFC...A RIDGE EXTENDED FROM HUDSON BAY INTO THE WRN GREAT LAKES RESULTING IN N TO NE FLOW INTO UPPER MICHIGAN. VIS LOOP SHOWED A CLEARING TREND WITH THE COMBINATION OF DRY ADVECTION AND DAYTIME MIXING HELPING TO SCOUR OUT THE LOW CLOUDS. AFTERNOON TEMPS RANGED FROM THE MID 30S NORTH...DOWNWIND OF LAKE SUPERIOR...TO THE MID 40S OVER THE SOUTH. TONIGHT...EVEN THOUGH THERE MAY BE SOME INCREASE IN HIGH CLOUDS OVERNIGHT AND SOME LIGHT EAST WINDS...EXPECT RADIATIONAL COOLING CONDITIONS WILL BE FAVORABLE ENOUGH TO ALLOW TEMPS TO DROP TOWARD THE LOWER 20S INLAND NORTH AND TO AROUND 30 NEAR THE WI BORDER. SUN...AS THE STRONG MID LEVEL AND SFC LOW MOVE INTO THE CNTRL PLAINS WAA PCPN AHEAD OF THE 850 MB WARM FRONT MAY APPROACH UPPER MI AS IT SPREADS THROUGH WI. HOWEVER...WITH PERSISTENT ERLY LOW LEVEL DRY ADVECTION AND THE VERY DRY PROFILE BELOW 750 MB...PER FCST SOUNDINGS...EXPECT THAT THE PCPN WILL STAY TO THE SOUTH OF THE CWA. TEMPS WILL REMAIN BELOW NORMAL...WITH HIGHS IN THE MID 40S TO AROUND 50 OVER MUCH OF UPPER MICHIGAN. HOWEVER...OVER N CNTRL UPPER MI AND THE KEWEENAW...THE EAST WIND OFF OF LAKE SUPERIOR WILL KEEP HIGHS FROM AROUND 40 TO 45. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 417 PM EDT SAT APR 26 2014 UPPER LOW BEGINS THE LONG TERM PERIOD LUMBERING OUT OF THE SOUTHWEST CONUS ACROSS THE CENTRAL PLAINS. SFC LOW NEARBY THE UPPER LOW CENTER WHILE HIGH PRESSURE RIDGE EXTENDS SOUTHWARD FROM HUDSON BAY TO THE GREAT LAKES. UPPER LOW AND ASSOCIATED BLOCKING ALOFT ON ITS EDGES WILL BE MAIN WEATHER INSTIGATORS FOR THE UPCOMING WEEK. IT SEEMS TO ALWAYS BE A STRUGGLE FOR THE MODELS WITH THIS TYPE OF SITUATION WHERE THE UPPER LOW AND ASSOCIATED MOISTURE TRANSPORT RUN INTO THE SFC HIGH AND DRY LOW-LEVEL AIR. MOISTURE ADVECTION ALOFT COULD ALLOW FOR A LOT OF MID CLOUDS AND PERHAPS SOME LGT RAIN OVER THE SOUTHERN CWA MONDAY AFTN INTO MONDAY EVENING. FARTHER NORTH...THINK LOWER SFC-H85 RH OUT OF THE HUDSON BAY HIGH WILL LIMIT ANY PRECIP TO ISOLD SHOWERS OR SPRINKLES. EAST-NORTHEAST WINDS WILL KEEP LK SUPERIOR AREAS IN THE LOWER 40S ON MONDAY...BUT INLAND AREAS CLOSER TO WI BORDER AND OVER THE EASTERN CWA MAY BE ABLE TO PUSH INTO THE 50S WITH BETTER MIXING HEIGHTS UP TO H85. POSSIBLE THAT MID 50S COULD OCCUR OVER FAR EAST IF CLOUDS HOLD OFF LONG ENOUGH. ENOUGH CONFIDENCE THAT ONCE TUESDAY AND WEDNESDAY ARRIVE...UPPER LOW WILL BE EXERTING ENOUGH OF AN INFLUENCE TO RESULT IN PRECIPITATION ACROSS THE CWA. EAST WINDS WITH CLOUDS AND PRECIP WILL KEEP TEMPS IN ALL AREAS WELL BLO NORMAL...WITH HIGHS THIS PERIOD UPR 30S TO LOW 40S NEAR LK SUPERIOR AND MAINLY IN THE 40S INLAND. AS IT APPEARS NOW...AND THIS IS SUBJECT TO CHANGE...SEEMS THAT PRECIPITATION COMES IN TWO WAVES. FIRST MAIN AREA OF PRECIPITATION SUPPORTED BY INITIAL SHORTWAVES ROTATING AROUND THE UPR LOW AND H85-H7 MOISTURE TRANSPORT LIFTS ACROSS THE CWA ON TUESDAY. GFS AND ECMWF SUGGESTS STEADIER PRECIP COULD CHANGE TO MAINLY DRIZZLE TUESDAY AFTN INTO TUESDAY EVENING. PTYPE COULD BE AN ISSUE INITIALLY AS H85 TEMPS BLO ZERO OVER THE WESTERN CWA AND SFC TEMPS IN THE LOW-MID 30S MONDAY NIGHT INTO TUESDAY MORNING POINT TO POSSIBLE RAIN/SNOW MIX. 1000-850MB THICKNESSES RIGHT ON THE 1300-1305M LINE WOULD INDICATE DIFFERENCE BTWN SEEING RAIN...SNOW...OR A MIX WILL BE DEPENDANT ON ELEVATION HEIGHT. THERE IS NOT A LOT OF PRECIP EXPECTED MOST OF MONDAY NIGHT FOR AREAS IN THE RAIN/SNOW ZONE...BUT PRECIP TUESDAY MORNING COULD BE MORE IMPACTED. WOULD NOT BE SURPRISED TO SEE SLUSHY SNOW ACCUMS ON TUESDAY MORNING OVER THE HIGHER TERRAIN OF THE NORTHWEST AND NORTH CENTRAL CWA. ANY MIX WOULD CHANGE TO RAIN IN THE AFTN AS RELATIVELY WARMER AIR ARRIVES FROM THE SOUTH. KEPT RAIN CHANCES FOR TUESDAY NIGHT BUT IT COULD BE DRIZZLE AT TIMES. BEST CHANCE OF RAIN OVER THE EASTERN CWA AHEAD OF STRONGER SHORTWAVE LIFTING IN LATER TUESDAY NIGHT. SHORTWAVE LIFTS ACROSS AREA ON WEDNESDAY WHICH IS ALSO WHEN MAIN SFC LOW ARRIVES OVER THE REGION. EVEN THOUGH BETTER MOISTURE TRANSPORT IS HEADING EAST BY THAT TIME...THERE IS HINT OF WARM AND MOIST AIR WRAPPING BACK ACROSS UPR LAKES AS THE SFC LOW BEGINS TO OCCLUDE. KIND OF EARLY TO BE LOOKING AT TROWAL SPECIFICS BUT THAT MAY BE WHAT MODELS ARE KEYING ON TO BOOST QPF TOTALS ALONG TRACK OF H85 LOW TRACK. UPSLOPE NNW FLOW MAY ALSO INCREASE TOTALS OVER WEST AND NCNTRL LATER WEDNESDAY INTO WEDNESDAY NIGHT. STILL APPEARS THAT TOTAL PRECIP TUESDAY AND WEDNESDAY...AT LEAST IN SOME AREAS...MAY REACH 1 TO 1.5 INCHES. LATER WEDNESDAY NIGHT INTO THURSDAY MAY HAVE TO DEAL WITH MORE PTYPE ISSUES AGAIN AS VERTICALLY STACKED LOW PRESSURE ALLOWS FOR GRADUALLY COOLING TEMPERATURES JUST ABOVE SFC. H85 TEMPS DROP BACK BLO 0C SO COULD SEE MORE RAIN AND SNOW MIX FOR THE WEST HALF OF CWA WEDNESDAY NIGHT INTO THURSDAY MORNING. UNRAVELLING UPPER/SFC LOWS ONLY SLOWLY MOVE OUT OF THE AREA LATE THIS WEEK. ADDITIONAL SHORTWAVES MAY BRING MORE UNSETTLED WEATHER FRIDAY INTO SATURDAY /BOTH RAIN AND SNOW POSSIBLE/...BUT GRADUALLY POPS WILL DROP BACK TO SLIGHT CHANCES BY THAT TIME. CONSENSUS MAX TEMPS CONTINUING TO STAY BLO NORMAL ARE NOT NECESSARILY DESIRED...BUT APPEAR REASONABLE TO CLOSE THE LONG TERM PERIOD. MADE FEW CHANGES TO CONSENSUS TEMPS/POPS/WINDS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 125 AM EDT SUN APR 27 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME INCREASE IN MID CLOUDS TOWARDS THE END OF THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 417 PM EDT SAT APR 26 2014 EAST WINDS INCREASE ON SUNDAY INTO SUNDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE PLAINS. GUSTS COULD REACH GALE FORCE TO 35KTS OVER FAR WESTERN LK SUPERIOR TOWARD DULUTH BY LATE AFTERNOON. EAST GALES ARE THEN EXPECTED SUN NIGHT INTO MON OVER THE WEST. WINDS WILL GRADUALLY DIMINISH MON NIGHT INTO TUE AS THE LOW PRESSURE SYSTEM LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED INTO TUE. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO THU AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 417 PM EDT SAT APR 26 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. WHILE THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION ARE NOT EXPECTED TO REACH FLOOD STAGE IN THE SHORT TERM...THE STURGEON RIVER NEAR CHASSELL REMAINS NEAR FLOOD STAGE AND IS EXPECTED TO REMAIN STEADY FOR THE REST OF THE WEEKEND. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. A LARGE LOW PRESSURE SYSTEM WILL MOVE INTO THE GREAT LAKES BY THE MIDDLE OF NEXT WEEK. PERIODS OF RAIN ARE POSSIBLE FROM LATE MONDAY THROUGH THURSDAY WITH THE POTENTIAL FOR TOTAL AMOUNTS OF AN INCH TO AN INCH AND A HALF. THIS WOULD ADD TO THE FLOOD RISK...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN WHERE SNOWMELT WILL ALSO ADD TO THE RUNOFF. WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS OVER THE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM THIS AFTERNOON THROUGH MONDAY EVENING FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLB HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
324 AM CDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT SUN APR 27 2014 THE SHORT TERM FORECAST CONCERNS REVOLVE AROUND THE IMPACTS OF THE ANOMALOUSLY STRONG TROUGH LIFTING FROM THE GREAT BASIN REGION OF THE SOUTHWESTERN CONUS TO THE CENTRAL PLAINS...NAMELY THE STRONG WINDS TODAY AND POTENTIAL FOR EXCESSIVE RAINFALL TONIGHT. SHOWERS AND THUNDERSTORMS WILL CONTINUE TO EXPAND ACROSS THE AREA IN WAVES TODAY...WHICH WILL MEAN 1-3 HOUR PERIODS OF PRECIPITATION FOLLOWED BY BRIEF RESPITES BETWEEN WAVES. HAVE TRIED TO CAPTURE THIS DIFFICULT SCENARIO IN THE HOURLY POP GRIDS...WITH THE AID OF THE HRRR COMPOSITE REFLECTIVITY. AFTER THE MAIN NOCTURNALLY-DRIVEN ACTIVITY EXITS THE AREA...EXPECT ACTIVITY TO BECOME MORE SPOTTY IN NATURE DURING THE MORNING...UNTIL MORE ROBUST AND ORGANIZED DIURNALLY-DRIVEN SHOWERS AND THUNDERSTORMS ORIGINATED IN THE VICINITY OF THE SURFACE TROUGH /WARM FRONT/ OVER SODAK/NE/IA LIFT NORTHEAST INTO THE AREA BY 00Z. TONIGHT WILL BE INTERESTING...PARTICULARLY FROM A HYDRO PERSPECTIVE...AS PWAT VALUES SOAR TO 200 PERCENT OF NORMAL AND STRONG 850-700MB MOISTURE TRANSPORT FEEDS INTO THE AREA NORTH OF THE WARM FRONT. FOCUS WILL BE ON SOUTHEASTERN MN AND WEST CENTRAL WI...WHERE 1-2 INCH SIX- HOURLY AMOUNTS APPEAR ACHIEVABLE ON SUNDAY NIGHT. AT THIS POINT...THE PLACEMENT OF THE KEY PLAYERS FOR SEVERE WEATHER /I.E. WARM FRONT/ APPEAR TO LIE FAR ENOUGH SOUTH TO KEEP SURFACE BASED STORMS /AND SEVERE ACTIVITY/ TO THE SOUTH OF MN/WI. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 323 AM CDT SUN APR 27 2014 HIGH CONFIDENCE THAT A LARGE SYNOPTIC SCALE UPPER LOW WILL DOMINATE THE CENTRAL PART OF THE CONUS THRU THE UPCOMING WEEK. BY MONDAY...THIS STORM SYSTEM WILL BE VERTICALLY STACKED AND ON THE WEAKENING SIDE AS IT BEGINS TO FILL AND MENANDER ACROSS THE MIDWEST AND EVENTUALLY THE GREAT LAKES REGION BEFORE LIFTING OFF TO THE NE BY NEXT WEEKEND. HOWEVER...DUE TO THE LARGE EXTENT OF THIS SYSTEM AND VERY LITTLE UPPER SUPPORT TO MOVE IT OUT QUICKLY...MODELS MAYBE TOO FAST AS IT BEGINS TO LIFT ACROSS THE GREAT LAKES BY THU/FRI. IN ADDITION...AN UPPER RIDGE WILL BUILD ACROSS SOUTH CENTRAL CANADA...BASICALLY HOLDING THE UPPER LOW FROM MOVING TO THE NORTH OR NORTHEAST. THE MEAN UPPER FLOW WILL BE EAST TO WEST ACROSS SOUTHERN CANADA WHICH LEADS TO THE LOW CONFIDENCE ON HOW QUICK THIS SYSTEM BEGINS TO MOVE OUT. WHAT THIS MEANS AT THE SFC IS A LONG PERIOD OF CLOUDS...PRECIPITATION AND COOL CONDS. THE BEST CHC/S OF WIDESPREAD PRECIPITATION ALONG WITH LOCALLY HEAVY RAINFALL WILL OCCUR BEFORE MONDAY...WITH MAINLY DIURNALLY DRIVEN AFTN/EVENING SHRA IF ANY BREAKS IN THE OVERCAST OCCURS. THERE IS EVEN A CHC OF SNOW SHOWERS MONDAY NIGHT/TUESDAY MORNING...AND AGAIN TUESDAY NIGHT/WEDNESDAY MORNING AS COLDER TEMPS WRAP AROUND THE CORE OF THIS SYSTEM EARLY NEXT WEEK. TEMPS WILL LIKELY HOLD IN THE 40S AND LOWER 50S FOR HIGHS AND LOWS IN THE 30S AND LOWER 40S. ALTHOUGH LIKELY AND HIGH CHC POPS SEEM REASONABLE THRU WEDNESDAY AS THE CORE OF THE MAIN STORM SYSTEM MOVES OVERHEAD...THERE WILL BE A GENERAL LOWERING OF THE CHC/S BY LATER IN THE WEEK AS THE DEEPER MOISTURE AND ENERGY FROM THE UPPER LOW MOVES FURTHER AWAY. AGAIN...THIS IS HIGHLY DEPENDENT ON WHEN THE UPPER LOW MOVES OUT OF THE REGION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1039 PM CDT SAT APR 26 2014 THE GENERAL TREND TOWARD DETERIORATING CONDITIONS STILL LOOKS TO BE INTACT AS WE MOVE THROUGH THE FORECAST PERIOD. STILL A FAIR DEGREE OF UNCERTAINTY WITH RESPECT TO WHEN WE/LL SEE INDIVIDUAL WAVES OF PCPN OVER THE UPCOMING 24 HOURS... BUT TRENDED TOWARD LATEST HRRR AND CAM SOLUTIONS. THESE SUGGEST CURRENTLY LINGERING PCPN WILL LIFT NORTH AND SLOWLY DISSIPATE OVERNIGHT... WITH REDEVELOPMENT AND BLOSSOMING OF PCPN OVER THE SOUTH LATER TONIGHT INTO SUNDAY MORNING AS BETTER LARGE SCALE FORCING WORK INTO THE AREA IN ADVANCE OF UPPER WAVE AND SURFACE LOW. THE REAL QUESTION THEN BECOMES WHETHER AND WHEN WE/LL SEE GAPS IN THE PCPN... AND WHEN LOWER CEILINGS WILL ARRIVE TO STAY. WAS A BIT MORE OPTIMISTIC IN HANGING ONTO HIGHER CEILINGS A BIT LONGER THAN PREVIOUS FORECAST... MORE IN LINE WITH LATEST NAM... BUT COULD CERTAINLY SEE THAT NOT OCCURRING SHOULD THE LOW LEVEL MOISTEN MORE QUICKLY THAN SUGGESTED. COULD ALSO SEE LOWER VISIBILITIES... BUT MUCH WILL DEPEND ON PCPN RATES AND DEGREE OF BR WHICH OCCURS WITH THE PCPN. KMSP...HAVE DECENT CONFIDENCE ON THE OVERALL TRENDS AND CHANGES... BUT TIMING OF PCPN WAVES COULD EASILY DIFFER BY SEVERAL HOURS... AND ULTIMATE CEILINGS/VISIBILITIES COULD BE WORSE THAN INDICATED A BIT SOONER. STRONG EAST WINDS FOR MOST OF THE PERIOD STILL LOOK TO BE A GOOD BET... BUT THE GUSTINESS IS STILL QUESTIONABLE. /OUTLOOK FOR KMSP/ MONDAY...MVFR CEILINGS AND VISIBILITIES... IFR POSSIBLE. PERIODS OF RAIN... CHANCE OF THUNDER. EAST WIND 15 TO 25 KT BECOMING NORTHEAST. MONDAY NIGHT...MVFR CEILINGS AND VISIBILITIES... IFR POSSIBLE. PERIODS OF RAIN... CHANCE OF THUNDER. NORTHEAST WIND 10 TO 20 KT. TUESDAY AND TUESDAY NIGHT...MVFR CEILINGS AND VISIBILITIES... IFR POSSIBLE. PERIODS OF RAIN. NORTHEAST WIND 10 TO 20 KT BECOMING NORTH. WEDNESDAY...MVFR CEILINGS AND VISIBILITIES. RAIN LIKELY. NORTH WIND 10 TO 20 KT BECOMING NORTHWEST. && .HYDROLOGY... ISSUED AT 323 AM CDT SUN APR 27 2014 WESTERN WISCONSIN RIVERS SILL REMAIN A FOCI...PARTICULARLY OVER THE NEXT 24 TO 36 HOURS...WITH WIDESPREAD 1-2 INCH RAINFALL AMOUNTS EXPECTED. AS OF NOW HOWEVER...THE HIGHER PROBABILITIES FOR 3+ TOTALS APPEAR TO LIE SOUTH AND EAST OF THE AREA...WHICH IS WHAT THE RIVERS IN WESTERN WI WOULD NEED FOR FLOODING TO OCCUR. THEREFORE...THE RISK REMAINS LOW UNLESS CONVECTION TONIGHT GETS OUT OF HAND FROM A HEAVY RAIN STANDPOINT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ041-047-048- 054>058-064>066-073. WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR MNZ067-074>077-082>085-091>093. WI...NONE. && $$ SHORT TERM...LS LONG TERM...JLT AVIATION...TRH HYDROLOGY...LS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
1142 PM MDT SAT APR 26 2014 .UPDATE... RED LODGE REPORTING 3 INCHES OF WET SNOW SO FAR...LIVINGSTON ASOS IS MIXING WITH SNOW...JUDITH GAP OBS SUGGEST SNOW...AND WE RECEIVED A SPOTTER REPORT OF SNOW NOW AT RAPELJE. BLX RADAR SHOWS MIXED PCPN DOWN TO ABOUT 4500 FEET...AND THIS IS CONSISTENT WITH THE VARIETY OF REPORTS WE HAVE RECEIVED OVER THE PAST COUPLE HOURS. HAVE MADE SOME WX/SNOW/TEMP ADJUSTMENTS TO ACCOUNT FOR THIS. AS FAR AS PCPN GOES...AN INCH OR MORE OF RAIN HAS FALLEN AT COLUMBUS AND EDGAR AS OF 11PM AND IT IS NOT DONE YET. LOOKS LIKE TOTALS WILL REACH AN INCH AND A HALF IN PLACES BETWEEN BILLINGS AND BIG TIMBER BY THE TIME THE PCPN TAPERS OFF. MID LEVEL LOW STILL PRODUCING SOME MODERATE PCPN IN THIS AREA...BUT DRIER AIR NOTED NEAR CODY IS MOVING NORTHWARD. MID LEVEL FRONTOGENESIS WILL WEAKEN OVER THE NEXT FEW HOURS AND DOWNSLOPE WINDS WILL BEGIN TO DEEPEN SO EXPECT PCPN IN OUR WEST TO TAPER OFF SIGNIFICANTLY OVERNIGHT. FOCUS WILL THEN TURN TO OUR EAST...NOTE THE CONVECTIVE PCPN IN WESTERN SD AND EASTERN WY LIFTING NORTHWARD. JKL && .SHORT TERM...VALID FOR SUN AND MON... SCATTERED SHOWERS AND THUNDERSTORMS WERE MOVING N TOWARD THE FORECAST AREA FROM WY THIS AFTERNOON PER RADAR IMAGERY AND LIGHTNING DATA. CAPES HAVE BEEN INCREASING OVER THE AREA SO HAVE INCREASED THE CHANCE OF THUNDER FOR THIS EVENING. THE CAPES WERE FORECAST TO DIMINISH BY THE RAP AFTER 03Z...SO WILL ONLY HAVE A SLIGHT CHANCE OF THUNDER FOR THE LATE EVENING. BULK SHEAR WAS ALSO FAVORABLE ACROSS THE REGION IN SUPPORT OF THUNDERSTORMS. COMPACT UPPER LOW WAS SEEN ON WATER VAPOR IMAGERY MOVING THROUGH AZ THIS AFTERNOON. PLENTY OF MOISTURE WAS SPREADING N OUT FROM THE LOW IN SW FLOW ALOFT. MODELS AGREED THAT THE UPPER LOW WILL REACH SE CO BY 12Z SUN...ALLOWING THE TROUGH TO GO NEGATIVE TILT AND TAP GULF OF MEXICO MOISTURE. THE LOW WILL MERGE WITH THE NORTHERN BRANCH OF THE TROUGH AS IT MOVES NE THROUGH MON INTO THE CENTRAL PLAINS. THE LARGER CUTOFF WILL THEN MEANDER E MON NIGHT. AT THE SURFACE...AMORPHOUS LOW CENTERS WERE ALONG THE SOUTHERN EDGE OF THE FORECAST AREA THIS AFTERNOON. THESE LOWS WERE FORECAST TO MERGE OVER NE OR E CO BY 12Z SUN WITH AN INVERTED TROUGH EXTENDING FROM THE MERGED LOW INTO THE EASTERN FORECAST AREA. A HALF INCH TO AN INCH OF QPF WILL FALL OVER THE WESTERN ZONES TONIGHT BEFORE THE PRECIPITATION FOCUS SHIFTS TO SE MT...E OF KBIL...DURING SUN MORNING DUE TO THE INVERTED TROUGH. THE INVERTED TROUGH WILL SHIFT SLOWLY E DURING SUN AND A HALF INCH TO AN INCH OF PRECIPITATION IS EXPECTED TO FALL OVER SE MT. THE BEST CHANCES FOR SNOW WILL BE THIS EVENING OVER THE BEARTOOTHS AND ABSAROKAS DUE TO A COMBINATION OF LIFT AND INSTABILITY...BUT DENDRITIC GROWTH WILL BE HIGHER IN THE ATMOSPHERE LIMITING THE GREATER ACCUMULATIONS TO THE HIGHEST ELEVATIONS. THE MAJORITY OF THE MODELS KEPT THE INVERTED TROUGH AND ASSOCIATED PRECIPITATION GOING OVER THE SE THROUGH MON WITH THE ECMWF BEING FURTHEST E OVER THE DAKOTAS. ANOTHER THREE-QUARTERS OF AN INCH OF PRECIPITATION WILL BE POSSIBLE SUN NIGHT...WITH MUCH LESSER AMOUNTS EXPECTED MON. SOME LINGERING PRECIPITATION IS EXPECTED OVER THE SE MON NIGHT. CONTINUED THE FORECAST OF RAIN MIXING WITH THE SNOW LATE SUN NIGHT AND MON NIGHT. A COUPLE INCHES OF SNOW WILL BE POSSIBLE OVER THE SE SUN NIGHT. ONLY MADE SLIGHT POP AND TEMPERATURE ADJUSTMENTS THROUGH THE PERIOD. HIGHS WILL BE IN THE 40S AND 50S SUN AND MON. STILL EXPECTING GUSTY NW WINDS BEHIND THE SURFACE LOW BEGINNING TONIGHT. WILL CONTINUE THE ESF FOR RISING RIVERS AND STREAMS. ARTHUR .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... THE LARGE SCALE SYNOPTIC PATTERN ACROSS THE CONUS WILL EVOLVE SLOWLY THROUGH MIDDLE TO LATE NEXT WEEK AS A BLOCKING PATTERN CONTINUES. TUESDAY THROUGH THURSDAY THE LARGE UPPER-LEVEL LOW WILL DRIFT FROM THE CENTRAL PLAINS TO THE GREAT LAKES AREA... WHICH WILL RESULT IN A CONTINUED WET AND COOL PATTERN FOR THE EASTERN PORTIONS OF THE FORECAST AREA. THE MOISTURE TRANSPORT WILL SLOWLY DIMINISH EACH DAY... AND WILL ALLOW PRECIPITATION TO SLOWLY TAPER OFF. WHILE MODELS HAVE CONTINUED TO SHOW SLOW BREAKDOWN OF THE BLOCKING PATTERN... THURSDAY WILL FINALLY BE WARMER AND DRIER AS ANTICYCLONIC FLOW FINALLY BUILDS IN ALOFT ALONG WITH WARMER 850 MB TEMPERATURES. THE MODEL TREND HAS BEEN TOWARD A SLIGHTLY SLOWER PROGRESSION OF THE MEAN UPPER-LEVEL LOW ON TUESDAY AND WEDNESDAY... WHICH WILL COMBINE WITH SOME ADDITIONAL VORTICITY BEING ADVECTED IN TO THE FORECAST AREA FROM THE EAST ON TUESDAY. THIS WILL MAKE FOR A WETTER TUESDAY ACROSS EASTERN MONTANA THAN WE INITIALLY THOUGHT. THUS...HAVE DECIDED TO INCREASE POPS TO LIKELIES FOR AREAS EAST OF FORSYTH ON TUESDAY AFTERNOON. TEMPERATURES WILL ALSO BE FAIRLY COOL ACROSS THE EAST ... WITH THERMAL PROFILES SHOWING THE POTENTIAL FOR SNOW TO MIX WITH RAIN EARLY TUESDAY MORNING AND THEN AGAIN EARLY WEDNESDAY MORNING. FARTHER WEST THE TEMPERATURES WILL SLOWLY START TO MODERATE INTO WEDNESDAY AS THE NORTH-SOUTH ORIENTED JET STREAM SLOWLY PUSHES EASTWARD AND ALLOWS FOR +10C 850 MB TEMPERATURES TO MOVE INTO THE WEST HALF OF THE FORECAST AREA. SHOWERS ARE STILL POSSIBLE ACROSS SOUTH CENTRAL MONTANA ON TUESDAY AND WEDNESDAY ... GIVEN SOME ADDITIONAL FORCING WRAPPING BACK AROUND THE LOW...HOWEVER THE MAIN DETERRENT TO REALIZING THIS POTENTIAL REMAINS THE STRONG NORTHWESTERLY DOWNSLOPE WINDS. ANOMALOUSLY STRONG NORTHWESTERLY WINDS WILL CONTINUE FOR MUCH OF THE FORECAST AREA ON TUESDAY..WITH THE WINDS SLOWLY TAPER- ING OFF WEDNESDAY INTO THURSDAY. THE PATTERN FAVORS STRONGEST WINDS ACROSS SOUTHEAST MONTANA AND INTO SHERIDAN WY GIVEN THE SURFACE LOW ACROSS THE CENTRAL CONUS SUPPORTING A TIGHT PRES- SURE GRADIENT ACROSS THE CENTRAL AND EASTERN CWA. CIPS ANALOG GUIDANCE SHOWS 50 TO 70 PCT CHANCE OF WIND GUSTS GREATER THAN 30 KTS FROM BILLINGS TO SHERIDAN AND ACROSS SE MT ON TUESDAY. AFTER THE WARMING AND DRYING TREND ON THURSDAY... MODEL SOLU- TIONS DIVERGE READILY. HOWEVER ... THE OVERALL TREND SEEMS TO BE TOWARD NORTHWESTERLY FLOW... WHICH KEEP US FROM WARMING UP SIGNIFICANTLY AND WILL KEEP A SLGT CHANCE OF PRECIPITATION IN THE FORECAST TO END THE WEEK. CHURCH && .AVIATION... SHOWERS AND ISOLATED EVENING THUNDERSTORMS WILL PROVIDE WIDESPREAD MVFR CONDITIONS TONIGHT. THE THUNDER THREAT WILL DECREASE OVERNIGHT. LOCATIONS ABOVE 5500 FEET WILL SEE WET SNOW AND IFR TO LIFR CONDITIONS. THE PRECIPITATION WILL BE HEAVIEST FROM KBIL WEST TONIGHT. THE HEAVIEST PRECIPITATION WILL SHIFT EAST OF KBIL ON SUNDAY. THE MOUNTAINS WILL GET SNOW AND BE OBSCURED THROUGH THE NIGHT INTO THE DAY SUNDAY. TWH && .PRELIMINARY POINT TEMP/POPS... SUN MON TUE WED THU FRI SAT ----------------------------------------------------------- BIL 038/056 036/051 035/053 036/057 037/062 039/065 041/058 +7/W 32/W 23/W 21/N 11/B 12/W 22/W LVM 035/057 033/047 032/051 033/057 035/060 035/062 037/061 +5/W 33/W 23/W 11/B 11/U 12/W 22/W HDN 041/056 033/051 035/052 033/058 032/061 035/066 038/059 99/W 65/W 34/W 42/W 11/B 12/W 22/W MLS 043/047 034/047 035/048 032/051 033/058 037/063 039/058 9+/R 97/O 56/R 53/W 11/B 12/W 22/W 4BQ 042/048 033/046 035/046 032/050 031/057 034/062 037/058 9+/R 97/O 56/R 53/W 11/B 12/W 22/W BHK 042/045 033/044 034/042 031/049 031/054 034/058 036/057 8+/R +8/O 66/R 43/W 12/W 12/W 22/W SHR 039/053 031/046 033/048 033/050 032/056 033/060 036/060 98/W 55/W 24/W 42/W 11/B 12/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
845 PM CDT MON APR 28 2014 .SYNOPSIS... ISSUED AT 337 PM CDT MON APR 28 2014 H5 ANALYSIS FROM THIS MORNING HIGHLIGHTS A NEGATIVE TILTED UPPER LEVEL LOW OVER CENTRAL NEBRASKA WITH A DOWN STREAM RIDGE EXTENDING FROM THE UPPER OHIO VALLEY NWWD INTO THE HUDSON BAY OF CANADA. A STRONG JET STREAK EXTENDED FROM NRN CALIFORNIA...TO CENTRAL TX...CURVING NE INTO THE OZARKS AND LOWER OHIO VALLEY. WITHIN THIS FEATURE...A 90+KT JET MAX EXTENDED FROM SERN OK INTO FAR NERN ARKANSAS. WV IMAGERY AS OF MIDDAY HAS THE UPPER LOW NEAR BROKEN BOW NEBRASKA. AT THE SURFACE...STRONG LOW PRESSURE WAS LOCATED OVER NERN NEBRASKA A COLD FRONT EXTENDED EAST SOUTHEAST OF THE LOW INTO SOUTH CENTRAL IOWA...SOUTH INTO CENTRAL ARKANSAS. STRONG WINDS CONTINUES ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON AND WINDS HAVE GUSTED AS HIGH AS 58 MPH AT THEDFORD AND NORTH PLATTE. OCCASIONAL SHOWERS WERE OCCURRING ACROSS SOUTHWESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON WITH SOME EMBEDDED THUNDERSTORMS IN FAR NORTHEASTERN PORTIONS OF THE FORECAST AREA. TEMPERATURES AT 3 PM CDT RANGED FROM THE MIDDLE 30S TO MIDDLE 40S. && .UPDATE... ISSUED AT 844 PM CDT MON APR 28 2014 NEDOR CAMS AND THE RAP MODEL SUGGEST 1 TO 5 INCHES OF SNOW TONIGHT SPREADING AS FAR EAST AS BROWN AND KEYA PAHA COUNTIES. THE WINTER WEATHER ADVISORY HAS BEEN EXPANDED EAST INTO THE THESE AREAS. WINDS APPEAR TO HAVE DIMINISHED BELOW HIGH WIND CRITERIA SO THE HIGH WIND WARNING HAS BEEN CANCELLED. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 337 PM CDT MON APR 28 2014 CLOSED LOW CONTINUES TO DRIFT SLOWLY ACROSS THE CENTRAL PLAINS. SEVERAL HAZARDS TO CONTENT WITH TONIGHT AND TOMORROW...INCLUDING STRONG WINDS...RAIN AND SNOW. THE SFC LOW MOVES ACROSS THE MISSOURI RIVER TONIGHT...MEANWHILE A HIGH PRESSURE BUILDS ACROSS THE NORTHERN ROCKIES. THIS WILL CREATE A TIGHT PRESSURE GRADIENT AND STRONG WINDS EXPECTED TO CONTINUE. MODELS IN GOOD AGREEMENT BY INCREASING 850 MB WINDS OVERNIGHT TO 60 KTS OVER SW NEB. WILL EXTEND THE HIGH WIND TO ACCOUNT FOR DAYTIME MIXING AND POTENTIAL FOR VERY STRONG WINDS. THEN OVERNIGHT EXPECT SLIGHTLY LESS MIXING AND A HIGH END WIND ADVISORY...HOWEVER WILL CONTINUE TO MONITOR CLOSELY. SO FAR TODAY THE SHOWERS HAVE HELP TO LIMIT THE MIXING AND EXPECT THE NEXT DEFORMATION BAND TO DEVELOP AND BRING ADDITIONAL PRECIPITATION AND LIMIT MIXING THE VERY STRONG WINDS TO THE SFC. NOW PRECIP IS AN ISSUE. 850 MB TEMPS BELOW ZERO ARE SPREADING INTO PORTIONS OF NW NEB EARLY TONIGHT IN THE NAM/EC/GEM...HOWEVER THE GFS IS A LITTLE SLOWER. THIS IS CRITICAL AS LIKE LAST NIGHT...NW NEB SHOULD SEE ENOUGH COLD AIR RETURN FOR SNOW. MODELS BRING MORE OF THE COLD AIR INTO CHERRY COUNTY...WHICH MAKES SENSE AS THE LOW IS A LITTLE FURTHER TO THE SE...AND EXPECT TO SEE SOME SNOW ACROSS SHERIDAN AND CHERRY COUNTY. A MIX OR A CHANGE TO ALL SNOW IS POSSIBLE FURTHER SOUTH AND EAST...AND THIS WILL NEED TO BE MONITORED. WILL ISSUE A WINTER WX ADVISORY FOR SHERIDAN AND CHERRY AS THE SNOW SHOULD PILE UP TO A FEW INCHES...AND CANNOT RULE OUT AROUND 6 NEAR THE BORDER. TOMORROW TEMPS WARM A LITTLE IN THE MORNING AND A CHANGE TO ALL LIQUID IS EXPECTED. MODELS BRING MORE DRY AIR INTO THE SYSTEM WHICH WRAPS ESPECIALLY INTO SW NEB. DID LOWER POPS AND COULD EASILY SEE LITTLE IF ANY PRECIP OVER THE SOUTHERN SANDHILLS AND SOUTHWEST NEB FOR THE AFTERNOON. MEANWHILE WINDS CONTINUE TO BE STRONG AND WILL CONTINUE THE WIND ADVISORY...CONVERTING THE WINTER WX TO A WIND ADVISORY AS THE SNOW IS EXPECTED TO END. THE BIG CONCERN HERE IS THE POTENTIAL FOR HIGH WIND CRITERIA IF WE SEE SOME BREAKS IN THE SKY. THIS WILL ALLOW FOR WARMER TEMPS AND BETTER MIXING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 337 PM CDT MON APR 28 2014 TUESDAY NIGHT THROUGH THURSDAY...WINDS AND PRECIPITATION CHANCES WILL BE THE MAIN FORECASTING CONCERNS FOR THE MIDDLE OF THIS WEEK. FOR TUESDAY NIGHT...THE LATEST MET/MAV GUIDANCE IS INDICATIVE OF BREEZY CONDITIONS CONTINUING INTO THE OVERNIGHT TUESDAY NIGHT. THIS WILL KEEP TEMPS FROM CRASHING INTO THE 20S. THERE IS SOME DISCREPANCIES BTW THE NAM AND GFS SOLNS WITH THEIR DEPICTION OF H85 TEMPS BY 12Z WEDNESDAY WITH THE GFS BEING 2 TO 4C COOLER COMPARED TO THE NAM SOLN. GIVEN THE DISCREPANCIES...DECIDED TO BLEND THE MAV AND MET GUIDANCE FOR LOWS TUESDAY NIGHT. THIS LED TO LOWS AROUND 30 IN THE WEST...TO 35 IN THE EAST. AS FOR PCPN CHANCES...THE LATEST MODELS PUSH A NICE PLUME OF DRY AIR INTO THE FORECAST AREA FROM NORTH TO SOUTH TUESDAY NIGHT. WE WILL STILL SEE SOME LOW CLOUDINESS ACROSS THE FORECAST AREA...HOWEVER...WITH MUCH DRIER AIR MOVING IN ABOVE 6000 FT AGL...DO NOT SEE MUCH OF A THREAT FOR PCPN ANYMORE AND HAVE ELIMINATED IT FROM THE FCST FOR OVERNIGHT TUESDAY NIGHT INTO WEDNESDAY MORNING. ON WEDNESDAY...THE UPPER LEVEL LOW WILL RETROGRADE NORTHWEST INTO CENTRAL AND SRN MINNESOTA. A NICE VORT LOBE WILL ROTATE AROUND THE WESTERN AND SOUTHWESTERN PERIPHERY OF THE LOW...AND WILL INCREASE THE THREAT FOR PCPN IN THE NORTHEASTERN CWA WEDS AFTERNOON/WEDS EVENING. ATTM...THE LATEST NAM AND GFS SOLNS ARE INDICATING SOME WEAK ISENTROPIC LIFT AT THE 295K LEVEL AND LOW COND PRESSURE DEFICITS IN THE EASTERN HALF OF THE FORECAST AREA DURING THE WEDS AFTN/EVE PERIOD. WINDS WILL BE GUSTY WEDNESDAY ONCE AGAIN...ESPECIALLY ACROSS THE WEST AND SOUTHWEST WHERE SOME CLEARING IS POSSIBLE...STEEP LAPSE RATES WILL FACILITATE GOOD MIXING. WITH H85 WINDS AROUND 35 KTS WEDS AFTN...ANOTHER WINDY DAY IS ON TAP ACROSS THE FORECAST AREA...AND MAY FACILITATE ISSUANCE OF YET ANOTHER WIND ADVISORY WEDNESDAY AFTERNOON INTO EARLY WEDS EVENING. BY THURSDAY...THE UPPER LEVEL LOW WILL FINALLY CLEAR THE MIDDLE AND UPPER MISSISSIPPI VALLEYS. THIS WILL LEAD TO LIGHTER WINDS THURSDAY AND WARMER TEMPS WITH READINGS REACHING THE LOWER TO MIDDLE 50S. FRIDAY TO MONDAY...THE UPPER LEVEL LOW WILL BE ABSORBED BY THE NORTHERN STREAM...BEING ABSORBED BY A QUASI STATIONARY LOW OVER CENTRAL CANADA. THIS WILL PLACE THE CENTRAL AND NORTHERN PLAINS IN A ZONAL FLOW PATTERN THIS WEEKEND INTO EARLY NEXT WEEK. TEMPERATURES WILL BE FAIRLY SEASONAL THIS WEEKEND WITH HIGHS GENERALLY IN THE 60S. MAINLY DRY CONDS ARE EXPECTED WITH THE EXCEPTION OF SATURDAY AND SATURDAY NIGHT. A MID LEVEL FRONTO BOUNDARY WILL BE DRAPED ACROSS THE NORTHERN FORECAST AREA AND SOUTH DAKOTA SATURDAY INTO SATURDAY NIGHT. AT THE SAME TIME...A NORTHERN STREAM WAVE WILL LIFT ACROSS THE NRN TIER OF STATES. ENHANCED LIFT WILL BE PRESENT ACROSS NRN NEBRASKA SATURDAY AND SATURDAY NIGHT...AND HAVE INSERTED SOME LOW POPS INTO THE FCST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 635 PM CDT MON APR 28 2014 AREAS OF MVFR/LOCAL IFR/LIFR CONTINUE TONIGHT...MAINLY ALONG AND EAST OF HIGHWAY 83. THE LARGE UPPER LOW DRIFTS EAST TUESDAY WITH MVFR SHIFTING SLOWLY EAST TOWARD HIGHWAY 183. VFR MAY BECOME WIDESPREAD ALONG AND WEST OF HIGHWAY 61. NOTE THE LOCAL IFR/LIFR TONIGHT WILL MOSTLY OCCUR ACROSS NRN NEB AS THE RAIN MIXES OR CHANGES TO WET SNOW. THIS FEATURE COULD CONTINUE TUESDAY MORNING. && .LBF WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ TUESDAY FOR NEZ004-005- 007-009-010-022>029-035>038-056>059-069>071-094. WINTER WEATHER ADVISORY UNTIL 10 AM CDT /9 AM MDT/ TUESDAY FOR NEZ004>006-008-094. WIND ADVISORY FROM 10 AM TO 7 PM CDT TUESDAY FOR NEZ006-008. && $$ UPDATE...CDC SYNOPSIS...CLB SHORT TERM...MASEK LONG TERM...CLB AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
409 PM CDT SUN APR 27 2014 .SYNOPSIS... ISSUED AT 407 PM CDT SUN APR 27 2014 A POTENT...UPPER LEVEL LOW WAS CENTERED OVER WESTERN KS THIS AFTERNOON. A NICE JET STREAK EXTENDED FROM NORTHERN CALIFORNIA...AROUND THE BASE OF THE LOW...NOSING INTO CENTRAL KS. DOWNSTREAM OF THE TROUGH...A HIGH AMPLITUDE...NEGATIVE TILTED RIDGE EXTENDED FROM THE SERN STATES INTO NRN MANITOBA. AT THE SURFACE...LOW PRESSURE WAS NOTED OVER GOODLAND KS WITH A COLD FRONT EXTENDING SSW INTO NERN NEW MEXICO. AN INVERTED TROUGH AXIS EXTENDED NORTH OF THE LOW ALONG THE COLORADO/KS BORDER INTO THE NEBRASKA PANHANDLE. WEST OF THIS INVERTED TROUGH...TEMPS WERE IN THE LOWER TO MID 40S...WHILE EAST OF THE TROUGH AXIS...TEMPS WERE IN THE 60S AND 70S. A DRY LINE...EXTENDED NORTH OF THE SURFACE LOW INTO SWRN NEBRASKA...WHERE IT TURNED SOUTHEAST INOT SOUTH CENTRAL NEBRASKA. THUNDERSTORMS HAVE FIRED ALONG THE DRYLINE THIS AFTERNOON WITH THE TORNADIC THREAT GENERALLY IN SOUTH CENTRAL NEBRASKA WHERE BETTER DIRECTIONAL SHEAR EXISTS. FURTHER NORTH ACROSS THE CENTRAL AND NORTHERN SANDHILLS...GOOD SPEED SHEAR EXISTS...HOWEVER DIRECTIONAL SHEAR IS LACKING PER LATEST KLNX VAD WIND PROFILER. IN THESE AREAS...STRONG TO SEVERE STORMS HAVE OCCURRED WITH LARGE HAIL BEING THE MAIN SEVERE THREAT. && .SHORT TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 407 PM CDT SUN APR 27 2014 FORECAST CONCERNS CONTINUE WITH THUNDERSTORM CHANCES TONIGHT...THEN LEAD TO FORMATION OF DEFORMATION BAND AND SNOW POTENTIAL. THE UPPER LOW WAS CENTERED OVER NORTHWEST KANSAS AS OF 20Z...WITH THE SURFACE CIRCULATION ALMOST DIRECTLY OVER KCBK. WITH THE SYSTEM BEING NEARLY VERTICALLY STACKED OVER NORTHWEST KANSAS THIS AFTERNOON...THERE IS CONCERN THAT THE MODELS MAY BE TRYING TO KICK THE SYSTEM EAST TOO QUICKLY THIS EVENING AND OVERNIGHT. THIS WILL IMPACT THE AREAS THAT CONTINUE TO SEE CONVECTION...WHERE THE PRECIPITATION FALLS...WHERE THE WINDS STRENGTHEN...AND WHERE AND WHEN THE RAIN SWITCHES OVER TO SNOW. THE LATEST RAP MODEL MOVES THE SURFACE CIRCULATION TO NEAR KMCK BY 00Z THIS EVENING THEN OVER KHSI AT 06Z AND THEN MOVES IT UP TO AROUND KBVN BY 12Z. THIS SOLUTION IS QUITE SIMILAR TO THE NEW 18Z NAM. THESE SOLUTIONS CONTINUE TO TRANSPORT MOISTURE AROUND THE CIRCULATION AND ACROSS WESTERN AND CENTRAL NEBRASKA THROUGH THE OVERNIGHT HOURS. STRONG FRONTOGENESIS SETS UP ON THE BACK SIDE OF THE SYSTEM...CENTERED OVER THE PANHANDLE AND WESTERN SANDHILLS OVERNIGHT. WITH GOOD MOISTURE IN THAT AREA AND SUBSTANTIAL LIFT DUE TO THE LARGE SCALE FORCING AND FRONTOGENESIS...EXPECT A GOOD DEFORMATION BAND TO BE ONGOING THROUGH MUCH OF THE NIGHT. SOME AREAS COULD SEE UP TO AN INCH OF MOISTURE BY 12Z MONDAY MORNING. THE BIG QUESTION WITH THE PRECIPITATION IS IF ENOUGH COLD AIR WILL MOVE IN TO GET SOME AREAS TO GET A CHANGEOVER TO SNOW. THE NAM AND THE RAP BOTH SHOW WET BULB PROFILES BELOW ZERO UNTIL ABOUT 300FT OR LESS ABOVE THE GROUND IN AREAS OVER THE NORTHEAST PANHANDLE...ESPECIALLY THE PINE RIDGE. IF THIS TURNS OUT...MAY SEE LOTS OF SNOW FALLING BUT WILL BE MELTING WHEN HITTING THE SURFACE OR JUST PRIOR. BUT...EVEN ONE DEGREE DIFFERENCE WILL BE ALL THAT IS NEEDED TO CHANGE OVER COMPLETELY TO SNOW AND IF RATES BECOME STRONG ENOUGH...COULD GET DECENT ACCUMULATIONS. AT THIS TIME...WITH THE MODELS ALL KEEPING THE WET BULB TEMPERATURE ABOVE 0C...DID PUT A COMPLETE CHANGEOVER TO SNOW IN THE NORTHWEST ZONES...BUT ONLY HAVE ACCUMULATIONS UP TO 2 INCHES ASSUMING THERE WILL BE SUBSTANTIAL MELTING AT THE SURFACE. THE NEXT QUESTION WILL BE WHAT WILL REMAIN FOR CONVECTION AND THUNDERSTORM CHANCES OVERNIGHT. KEPT AT LEAST A MENTION OF ISOLATED THUNDER IN AREAS ALONG THE INVERTED TROUGH GOING NORTH OF THE SURFACE LOW AS MOISTURE AND SOME WEAK INSTABILITY WILL CONTINUE TO CIRCULATE AROUND THE SYSTEM. MOVING ON TO WINDS...A VERY TIGHT PRESSURE GRADIENT WILL BE SEEN ON THE BACKSIDE OF THE SYSTEM...WHICH SHOULD CAUSE WINDS TO STRENGTHEN ACROSS THE AREA AS THE LOW MOVES EAST TONIGHT. THE ONGOING WIND ADVISORY FOR AREAS MAINLY WEST OF HIGHWAY 83 FOR THE OVERNIGHT PERIODS CONTINUES TO LOOK GOOD AS SUSTAINED WINDS AROUND 30MPH STILL LOOK LIKELY. WITH THE POTENTIAL FOR MODERATE TO HEAVY SNOW AND STRONG WINDS OVER THE NORTHEAST PART OF THE FORECAST AREA TONIGHT...DID CONSIDER A NEED FOR A WINTER WEATHER ADVISORY FOR LATE TONIGHT INTO MONDAY MORNING. AT THIS TIME...DUE TO THE UNCERTAINTY ON THE SWITCHOVER TO SNOW...OPTED TO NOT ISSUE AT THIS TIME AND WILL MONITOR CLOSELY IF HEADLINES ARE NEEDED. .LONG TERM...(MONDAY THROUGH SUNDAY) ISSUED AT 407 PM CDT SUN APR 27 2014 TOMORROW THROUGH WEDNESDAY...MAIN FORECAST CHALLENGES ARE WINDS AND PRECIPITATION CHANCES IN ASSOCIATION WITH A SLOW MOVING UPPER LEVEL LOW...WHICH WILL MIGRATE FROM EASTERN NEBRASKA INTO THE UPPER MISSISSIPPI VALLEY OVER THE NEXT 24 TO 84 HOURS. IN ADDITION TO PRECIPITATION CHANCES...THE THREAT FOR SNOW...PARTICULARLY DURING THE NIGHTTIME HOURS...WILL BE A CONCERN ACROSS NORTHERN NEBRASKA MONDAY NIGHT AND TUESDAY NIGHT. FOR MONDAY...PRECIPITATION CHANCES AND WINDS WILL BE THE MAIN FORECASTING CONCERN. ON MONDAY...THE MAIN UPPER LEVEL LOW WILL MEANDER ACROSS CENTRAL NEBRASKA...DRIFTING INTO EASTERN NEBRASKA BY LATE AFTERNOON. STRONG WINDS WILL DEVELOP ACROSS CENTRAL AND WESTERN PORTIONS OF THE FORECAST AREA MONDAY AS H85 WINDS REACH 40 TO 50 KTS IN THE SOUTHWEST AND SOUTHEASTERN PANHANDLE MONDAY AFTERNOON. WIND SPEEDS DECREASE FAIRLY QUICKLY EAST OF THE HIGHWAY 83 CORRIDOR AND DO NOT REALLY BEGIN TO KICK IN UNTIL MONDAY EVENING. TO AVOID CONFUSION...DECIDED TO HOIST A HIGH WIND WATCH FOR LOCATIONS ROUGHLY WEST OF A LINE FROM HAYES CENTER...TO ARTHUR...TO GARDEN COUNTY. IN THESE AREAS...A WIND ADVISORY WILL LIKELY BE NEEDED TOMORROW...BUT AT THIS TIME...I DO NOT HAVE ENOUGH CONFIDENCE TO ISSUE A HIGH WIND WARNING AND WILL ISSUE A WATCH AND LET THE MIDNIGHT CREW MAKE THE CALL. FURTHER EAST...TO THE HIGHWAY 83 CORRIDOR...NORTHERLY WINDS WILL INCREASE BY MIDDAY AND ARE EXPECTED TO REACH ADVISORY CRITERIA...FROM LINCOLN COUNTY NWD TO WESTERN CHERRY COUNTY AND WILL HOIST A WIND ADVISORY FOR THESE AREAS. IN ADDITION TO WIND...THERE IS STILL A SMALL THREAT FOR ACCUMULATING SNOWS MONDAY MORNING IN THE FAR NORTHWESTERN FORECAST AREA IN THE VICINITY OF THE PINE RIDGE. LIKE YESTERDAY...THE NAM HAS THE COLDEST BOUNDARY LAYER OF THE THREE MID RANGE MODELS. GIVEN THE LACK OF COLD UPSTREAM AIR ACROSS NERN WYOMING AND WESTERN SOUTH DAKOTA ATTM...AM INCLINED TO TREND TEMPS TOWARD THE WARMER GFS AND ECMWF SOLNS. WITH THIS IN MIND...HAVE WORDED THE FORECAST WITH A RAIN SNOW MIX THROUGH MID MORNING WITH LITTLE OR NO SNOW ACCUMS EXPECTED. WILL CONTINUE TO MONITOR THIS AREA CLOSELY. AS THE DAY PROGRESSES...WIDESPREAD RAIN WILL CONTINUE...ESPECIALLY ACROSS CENTRAL AND NORTHERN PORTIONS OF THE FORECAST AREA...WHERE A STRONG MID LEVEL DEFORMATION ZONE WILL SET UP AND PERSISTENT ISENTROPIC LIFT CONTINUES THROUGH THE AFTERNOON HOURS. ON MONDAY NIGHT...WINDS WILL INCREASE IN THE EAST AND SUBSIDE SOME IN THE WEST AS THE UPPER LEVEL LOW MEANDERS INTO SWRN IOWA AND NORTHWEST MISSOURI. WINDS WILL REMAIN ON THE GUSTY SIDE INTO THE OVERNIGHT HOURS...WHICH MAY NECESSITATE ISSUANCE OF A WIND ADVISORY MONDAY NIGHT. BASED ON THE LATEST MAV GUIDANCE AND BUFKIT DATA...ALMOST THE ENTIRE FORECAST AREA MAY NEED A WIND ADVISORY FOR MONDAY NIGHT. GIVEN THE ONGOING WIND HEADLINES...WILL HOLD OFF ON ISSUANCE ATTM TO AVOID CONFUSION WITH OUR CURRENT HEADLINES. DECENT ISENTROPIC LIFT CONTINUES INTO TUESDAY MORNING...ESPECIALLY OVER CENTRAL AND NORTHERN NEBRASKA AND WILL CONTINUE LIKELY TO CATEGORICAL POPS OVERNIGHT. TUESDAY THROUGH WEDNESDAY...THE UPPER LEVEL LOW WILL MEANDER EAST ON TUESDAY INTO WEDNESDAY...ENDING UP OVER THE WESTERN GREAT LAKES BY THURSDAY MORNING. DURING THE PERIOD...THE THREAT FOR LIGHT RAIN WILL CONTINUE TUESDAY WITH GUSTY WINDS EXPECTED AS WELL. H85 WINDS WILL DECREASE TO 35 TO 45 KTS ON TUESDAY...SO ANOTHER MAY BE NEEDED FOR TUESDAY ACROSS MOST OF THE FORECAST AREA. TEMPS WILL REMAIN COOL HOWEVER WITH MOSTLY CLOUDY SKIES AND WITH H85 TEMPS RANGING FROM -2C IN THE NORTHEAST...TO 3 C IN THE SOUTHWEST...HIGHS TUESDAY WILL STRUGGLE TO GET OUT OF THE UPPER 30S TO 40S. ON WEDNESDAY...H85 TEMPS WILL WARM TO 1C IN THE NORTHEAST...TO 5C IN THE SOUTHWEST. AFTERNOON HIGHS WILL REBOUND SLIGHTLY TO THE 40S TO LOWER 50S. WINDS WILL BE SOMEWHAT LIGHTER...THOUGH WINDY WITH WIND SPEEDS OF 20 TO 30 MPH...WITH SOME HIGHER GUSTS TO 40 MPH. AT THIS TIME...AM NOT ANTICIPATING ANY WIND HEADLINES ATTM. WEDNESDAY NIGHT AND BEYOND...THE UPPER LEVEL LOW WILL BE ABSORBED BY THE NORTHERN STREAM AND LIFTED EAST TOWARD THE END OF THE WEEK. HOWEVER...LOW PRESSURE ALOFT WILL REMAIN ANCHORED OVER SOUTH CENTRAL CANADA...AND WILL FORCE COLD AIR INTO THE NORTHERN PLAINS LATE IN THE WEEK INTO THE WEEKEND. MAINLY DRY CONDITIONS ARE EXPECTED WITH THIS FLOW REGIME. HIGHS WILL BE MORE MARCH LIKE WITH READINGS IN THE 50S EXPECTED FRIDAY...SATURDAY AND SUNDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1244 PM CDT SUN APR 27 2014 A VIGOROUS UPPER LEVEL LOW WILL TRACK NORTH INTO SOUTHERN PORTIONS OF NEBRASKA OVER THE NEXT 12 HOURS...BECOMING POSITIONED OVER NORTHERN NEBRASKA BY DAYBREAK ON MONDAY. THIS FEATURE WILL SPREAD THUNDERSTORMS TO THE KLBF AND KVTN TERMINALS THIS EVENING...FOLLOWED BY PERSISTENT RAIN SHOWERS AND STRONG NORTHWESTERLY WINDS INTO THE OVERNIGHT HOURS AND MONDAY MORNING. FOR THE KLBF TERMINAL...EXPECT THUNDERSTORMS IN THE VICINITY OF THE TERMINAL THROUGH MID AFTERNOON...WITH MORE PERSISTENT THUNDERSTORMS EXPECTED AFTER MID AFTERNOON. THIS THREAT WILL CONTINUE THROUGH 00Z MONDAY. SHOWERS ARE EXPECTED THEREAFTER WITH CIGS DROPPING DOWN TO 4000 TO 6000 FT AGL RAIN SHOWERS ARE EXPECTED TO END MONDAY MORNING...HOWEVER STRONG NORTHWESTERLY WINDS WITH GUSTS UP TO 40 KTS ARE LIKELY AFTER 15Z MONDAY. FOR THE KVTN TERMINAL...EXPECT OVERCAST SKIES WITH CIGS AROUND 5000 FT AGL THIS AFTERNOON WITH AN INCREASED THREAT FOR THUNDERSTORMS AFTER 21Z. THE THREAT WILL CONTINUE THROUGH EARLY EVENING WITH SHOWERS EXPECTED THEREAFTER. WINDS WILL SHIFT TO THE NORTH AFTER 00Z AND INCREASE WITH GUSTS UP TO 30 KTS POSSIBLE THROUGH 18Z MONDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 6 AM MDT MONDAY FOR NEZ022-035-056>058-069. HIGH WIND WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR NEZ022-035-056>058-069-070. WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ MONDAY FOR NEZ023>025- 036-037-059-071-094. WIND ADVISORY UNTIL 6 PM MDT MONDAY FOR NEZ004. WIND ADVISORY UNTIL 7 AM CDT MONDAY FOR NEZ070. WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR NEZ005-006-008- 009-026-027-038. && $$ SYNOPSIS...CLB SHORT TERM...BROOKS LONG TERM...CLB AVIATION...CLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1259 PM CDT SUN APR 27 2014 .MESOSCALE DISCUSSION... ISSUED AT 1259 PM CDT SUN APR 27 2014 THE COLD FRONT CURRENT EXTENDS FROM LEXINGTON-FRANKLIN-BELOIT KS. TOR WATCH HAS BEEN ISSUED FOR ALL AREAS N OF THE FRONT. AND WHAT IS DISCONCERTING IS THAT THE FRONT IS QUASI-STATIONARY. THE ANVIL CIRRUS FROM MORNING TSTMS OVER ERN NEB/KS HAS RAPIDLY THINNED. THE STATIONARITY OF THE FRONT MEANS A LONGER WINDOW OF OPPORTUNITY FOR SEVERE STORMS. VISIBLE SATELLITE SHOWS INCREASING CU DEVELOPMENT ALONG THE FRONT. WE HAVE ALREADY SEE SOME STORMS DEVELOP. MUCAPE IS CURRENTLY 500-1000 J/KG AND FURTHER INSOLATION WITH DEWPOINTS WELL INTO THE 50S MEANS FURTHER DESTABILIZATION. THE 17Z RAP SUGGESTS CAPE WILL PEAK 1200-2000 J/KG. WITH MORE THAN ADEQUATE SHEAR...THE ENVIRONMENT WILL ONLY BECOME MORE FAVORABLE FOR SEVERE TSTMS. BE ALERT FOR ABNORMAL STORM MOVEMENT IN OUR WARNINGS /TO THE N OR NW/. THESE STORMS WILL BE RACING 45-55 MPH. THAT MEANS YOUR OPPORTUNITY TO RESPOND TO THREATENING WX WILL BE REDUCED. ADDITIONAL STAFFING HAS ARRIVED. PLEASE FOLLOW ALL WARNINGS/STATEMENTS FROM THIS OFFICE AND WE WILL CONT TO PROVIDE MESOSCALE UPDATES VIA THIS PRODUCT AS THE EVENT UNFOLDS...TIME PERMITTING. STORM SPOTTERS AND EMERGENCY MANAGEMENT SHOULD NOW BE ACTIVATED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM CDT SUN APR 27 2014 THERE ARE NUMEROUS FORECAST CONCERNS TODAY INCLUDING THE POTENTIAL OF SEVERE THUNDERSTORMS...ALONG WITH HEADLINES FOR NON- THUNDERSTORM WINDS AND FIRE WEATHER. SEVERE THUNDERSTORMS...THE SEVERE THUNDERSTORM THREAT WAS THE PRIMARY THREAT FOCUSED ON IN THIS FORECAST PACKAGE. FORECAST MODELS HAVE REALLY COME INTO RATHER GOOD AGREEMENT WHEN IT COMES TO THE PROJECTED LOCATION OF THE BIG SYNOPTIC FEATURES TODAY INCLUDING THE SFC AND UPPER LOW POSITION ALONG WITH THE DRY LINE. HOW EXACTLY CONVECTION WILL ORGANIZE AND FORM WITH REGARD TO LOCATION AND TIMING DOES VARY FROM MODEL TO MODEL...BUT THERE IS A DECENT CONSENSUS THAT IS BUILDING. AS FOR THE BIG FEATURES...THE UPPER 500MB LOW WILL SWING ACROSS NORTHWESTERN KANSAS WITH THE SFC LOW JUST TO ITS NORTH OVER SOUTHWEST NEBRASKA. A DRY LINE WILL EXTEND IN AN ARC FROM NEAR THE SFC LOW TOWARDS THE SOUTHEAST AND LIFT NORTHEAST THROUGH THE DAY. THERE WILL BE A FAIRLY DECENT SIZED WARM SECTOR THAT WILL INCLUDE THE NORTHEASTERN HALF OF OUR FORECAST AREA AND MUCH OF EASTERN NEBRASKA. RECENT MODEL RUNS HAVE BEEN SLOWING THE DRY LINE DOWN THIS AFTERNOON. SOME THUNDERSTORMS ARE ALREADY ONGOING THIS MORNING TO OUR SOUTH AND EXPECT THUNDERSTORM ACTIVITY WILL CONTINUE TO PICK UP THROUGH THE MORNING WITH THE BEST CHANCE OF SEVERE THUNDERSTORMS ACROSS OUR AREA BETWEEN 11 AM AND 5 PM. THERE MAY BE MORE THAN ONE ROUND OF THUNDERSTORMS ACROSS OUR NORTHEASTERN ZONES AS THUNDERSTORMS FORM NEAR THE DRY LINE AND THEN MOVE OFF THE DRY LINE INTO THE WARM SECTOR WITH THIS SCENARIO POSSIBLY REPEATING ITSELF. THE GREATEST THREAT OF SEVERE WEATHER ACROSS OUR FORECAST AREA WILL BE ALONG AND NORTH OF THE DRY LINE...WHICH BY AROUND MID DAY SHOULD EXTEND FROM LEXINGTON...TO MINDEN...TO NELSON NEBRASKA. THUNDERSTORMS WILL BE MOVING NORTHERLY AT AROUND 40 TO 60 MPH...BUT COULD EVEN TRACK A LITTLE NORTHWESTERLY ACROSS OUR WESTERN FORECAST AREA IN CLOSER PROXIMITY TO THE SFC LOW. ALL FORMS OF SEVERE WEATHER INCLUDING LARGE HAIL...DAMAGING WINDS...AND TORNADOES WILL BE POSSIBLE TODAY. THIS IS A BIG SPRING STORM SYSTEM WITH A LOT OF WIND SHEAR AND AT LEAST MODEST INSTABILITY WITHIN THE WARM SECTOR. TORNADOES MAY COME FROM LESS THAN CLASSIC LOOKING SUPERCELLS INCLUDING SOME LOWER TOPPED SMALLER SUPERCELLS LOCATED CLOSE TO THE UPPER LOW AND THERE IS EVEN THE POTENTIAL OF SOME NON-MESOCYCLONE/LANDSPOUT TORNADOES GIVEN THE STEEP LAPSE RATES ALONG THE DRY LINE. SPOTTERS SHOULD BE READY FOR ACTIVATION TODAY. WIND ADVISORY...THE LAPSE RATES ARE DRY ADIABATIC ALL THE WAY TO 700 MB THIS AFTERNOON BEHIND THE DRY LINE AND EXPECT STRONG MIXING...WHICH WILL BRING DOWN STRONGER WINDS FROM ALOFT. MODEL GUIDANCE VALUES ARE GENERALLY JUST BELOW WIND ADVISORY THRESHOLDS...BUT HAVE BUMPED UP THE WINDS ABOVE MODEL GUIDANCE ACROSS SOME OF OUR KANSAS COUNTIES GIVEN THE STEEP LAPSE RATES AND HAVE ISSUED A WIND ADVISORY. THIS WIND ADVISORY MAY NEED TO BE EXPANDED FURTHER NORTHWARD TODAY. FIRE WEATHER...SEE FIRE WEATHER SECTION BELOW. TONIGHT...THINGS SHOULD REALLY QUIET DOWN BY LATE EVENING AS THE INSTABILITY IS USED UP AND DEWPOINTS FALL ACROSS OUR FORECAST AREA. LITTLE IF ANY PRECIPITATION IS EXPECTED TONIGHT...BUT CAN NOT RULE OUT A LITTLE SOMETHING DUE TO THE UPPER LOW TRACKING ACROSS THE WESTERN PORTIONS OF OUR FORECAST AREA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 353 AM CDT SUN APR 27 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR PRECIPITATION MONDAY THROUGH THURSDAY AND TEMPERATURES THROUGH THE PERIOD. A STRONG UPPER LEVEL LOW WILL BE THE MAIN FEATURE AFFECTING THE WEATHER THROUGH MOST OF THE PERIOD. THIS LOW WILL BRING PRECIPITATION CHANCES TO THE FORECAST AREA THROUGH THURSDAY BEFORE IT FINALLY MOVES FAR ENOUGH TO THE EAST. THE UPPER LOW WILL MOVE THROUGH NEBRASKA ON MONDAY. WRAP AROUND PRECIPITATION IS EXPECTED TO PUSH INTO THE AREA FROM THE NORTH WITH THE BEST CHANCES IN THE NORTH AND LITTLE TO NO PRECIPITATION EXPECTED FOR KANSAS. PRECIPITATION CONTINUES TO EXPAND MONDAY NIGHT AND MUCH OF THE AREA COULD HAVE PRECIPITATION. MODELS STILL HAVE A FEW MINOR DIFFERENCES AND ONE OF THEM IS THE AMOUNT OF COLD AIR. THE NAM AND THE ECMWF ARE COLDER THAN THE GFS. LATE MONDAY NIGHT INTO TUESDAY MORNING THE TEMPERATURES AT 850MB DIP BELOW FREEZING. THE SURFACE TEMPERATURES IN THE UPPER 30S SHOULD KEEP PRECIPITATION AS RAIN ALTHOUGH THERE COULD BE A SNOWFLAKE OR TWO IN THE NORTHWEST. THE UPPER LOW IS STILL IN THE MID MISSISSIPPI VALLEY ON TUESDAY AND THERE IS STILL A CHANCE FOR SOME SHOWERS THROUGH TUESDAY NIGHT. ONCE AGAIN THE 850MB TEMPERATURES DROP BELOW FREEZING AND WITH SURFACE TEMPERATURES IN THE MID 30S THERE COULD BE A FEW SNOWFLAKES MIXED IN. FOR NOW WILL KEEP THE TREND OF JUST RAIN SHOWERS...BUT THIS BEARS WATCHING. FOR WEDNESDAY INTO THURSDAY...THE UPPER LOW MOVES INTO THE GREAT LAKES BUT A COUPLE OF WAVES CIRCULATING AROUND THE LOW COULD BRING A FEW RAIN CHANCES DURING THE DAY WEDNESDAY AND THURSDAY. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS ONLY IN THE 50S. BY FRIDAY INTO SATURDAY THE UPPER LEVEL LOW WILL BE WELL OUT OF THE AREA. A SURFACE HIGH PRESSURE SYSTEM SETTLES INTO THE AREA ON FRIDAY AND TEMPERATURES WILL START TO WARM UP. WHEN THE SURFACE HIGH MOVES TO THE EAST ON SATURDAY THERE WILL BE SOME WARM ADVECTION AND TEMPERATURES WILL CONTINUE TO WARM INTO THE 60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1223 PM CDT SUN APR 27 2014 FOCUS WILL BE ON THE POTENTIAL FOR SEVERE THUNDERSTORM DEVELOPMENT WITHIN IN THE NEXT FEW HOURS. THE WINDS WILL BE STRONG FROM THE SOUTH AT 20 TO 25 KNOTS AND GUSTS CLOSER TO 35 KNOTS. EVENTUALLY...THESE WINDS WILL CALM DOWN AROUND 7 PM. WATCH FOR THUNDERSTORMS TO DEVELOP...RESULTING IN REDUCED FLIGHT CONDITIONS. && .FIRE WEATHER... ISSUED AT 353 AM CDT SUN APR 27 2014 DEWPOINT TEMPERATURES SHOULD RAPIDLY FALL LATER THIS MORNING AND THIS AFTERNOON BEHIND THE DRY LINE WITH INCREASING WINDS DUE TO INCREASED MIXING. CONSEQUENTLY...A RED FLAG WARNING HAS BEEN ISSUED FOR OUR SOUTHERN FORECAST ZONES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR NEZ072>075- 082>086. KS...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR KSZ005>007- 017>019. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ007-018-019. && $$ MESOSCALE...HALBLAUB SHORT TERM...WESELY LONG TERM...JCB AVIATION...GUERRERO FIRE WEATHER...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
103 AM CDT SUN APR 27 2014 .UPDATE... ISSUED AT 1006 PM CDT SAT APR 26 2014 MAP ANALYSIS INDICATES AN UPPER TROPOSPHERIC SHORTWAVE TROUGH OVER THE SOUTHWESTERN CONUS...WITH A LONGWAVE RIDGE EXTENDING FROM THE LOWER MISSISSIPPI VALLEY INTO THE MISSOURI RIVER VALLEY. UPPER TROPOSPHERIC JET ENERGY EXTENDS FROM THE SOUTHWESTERN CONUS...NORTHEAST INTO THE CENTRAL PLAINS...AND THEN EAST/SOUTHEAST INTO THE MID-ATLANTIC. DESPITE THIS UPPER TROPOSPHERIC JET ENERGY TRYING TO WORK INTO OUR AREA...UPPER TROPOSPHERIC FLOW REMAINS FAIRLY WEAK OVER OUR AREA...MAXING OUT AT AROUND 80KTS NEAR 37000FT AGL PER 00Z SOUNDING DATA FROM KLBF AND KOAX. WATER VAPOR IMAGERY SHOWS THE AFOREMENTIONED UPPER TROPOSPHERIC SHORT WAVE OVER THE SOUTHWESTERN CONUS...WITH INDICATIONS OF A CLOSED CIRCULATION OVER THE FOUR CORNERS AREA. PLENTY OF ENHANCED UPPER TROPOSPHERIC MOISTURE IS ALSO NOTED AHEAD OF THE SHORT WAVE MOVING INTO THE CENTRAL CONUS. AT THE SURFACE AN AREA OF LOW BAROMETRIC PRESSURE EXISTS OVER NORTHEASTERN COLORADO...WITH A STATIONARY BOUNDARY NOTED EXTENDING FROM THE LOW INTO CENTRAL NEBRASKA. A DRY LINE IS ALSO NOTED EXTENDING FROM NEAR KMCK TO NEAR KGCK. THE LOWER TROPOSPHERIC WIND FIELD ACROSS OUR AREA REMAINS FROM THE SOUTHEAST AS A RESULT. WITH THE UPPER TROPOSPHERIC SHORT WAVE REMAINING WELL SOUTHWEST OF THE REGION THUS LIMITING ANY SYNOPTIC-SCALE OMEGA OVER OUR AREA...AND WITH THE LOSS OF DIABATIC HEATING...CONVECTION ALONG/NEAR THE DRY LINE SEEMS HIGHLY UNLIKELY. THAT BEING SAID...A ~55KT JET AXIS JUST ABOVE THE BOUNDARY LAYER IS IN THE PROCESS OF DEVELOPING ACROSS OUR AREA AND GUIDANCE FROM THE HRRR AND 1KM WRF- NMM BOTH SUGGEST ISOLATED CONVECTION WILL BE POSSIBLE ACROSS OUR EASTERN CWA THROUGH 06Z. GIVEN THIS...WENT AHEAD WITH 20% POPS ACROSS OUR EAST 03-06Z. THE NAM AND OPERATIONAL GFS BOTH SUGGEST DEEP-LAYER MUCAPE VALUES WILL DROP INTO THE 100-200J/KG RANGE TONIGHT AND AS A RESULT...SEVERE WEATHER IS NOT CURRENTLY EXPECTED THROUGH THE REMAINDER OF THE NIGHT. ANY CONVECTION THAT DOES DEVELOP ACROSS OUR EAST IS EXPECTED TO QUICKLY MOVE NORTHEAST INTO THE MISSOURI RIVER VALLEY ALONG WITH THE NOSE OF THE LOW LEVEL JET. CLOSER TO SUNRISE...ANOTHER ROUND CONVECTION MAY ALSO DEVELOP ACROSS OUR EAST AS THE AXIS OF UPPER TROPOSPHERIC THERMAL ADVECTION...AHEAD OF THE UPPER TROPOSPHERIC SHORT WAVE AND DRY INTRUSION...MOVES INTO PORTIONS OF THE AREA. GIVEN THIS...WENT AHEAD WITH ANOTHER ROUND OF 20% POPS ACROSS OUR EAST 10-12Z SUNDAY...WITH POPS STILL EXPECTED TO INCREASE ACROSS MUCH OF THE AREA HEADING INTO THE DAY SUNDAY. REMAINDER OF THE FORECAST REMAINS IN GOOD SHAPE...WITH ONLY MINOR CHANGES MADE TO HOURLY TEMPERATURE...WIND...DEW POINT AND SKY GRIDS TO BETTER REFLECT CURRENTLY OBSERVATIONS. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 355 PM CDT SAT APR 26 2014 ...WE WILL BE MONITORING FOR ISOLATED SEVERE STORMS THIS EVENING AND THEN AGAIN TOMORROW FOLLOWED BY WINDY CONDITIONS... ALOFT: A POTENT/DEEP LOW WAS NEAR LAS VEGAS AND MOVING INTO AZ. THIS LOW WILL HEAD E TO THE 4-CORNERS BY 7PM AND THEN BEGIN TO TAKE ON NEGATIVE TONIGHT. IT WILL BE OVER ERN CO BY 7AM TOMORROW AND LIFT NE INTO WRN NEB BY SUNSET. SURFACE: EVOLUTION WILL BE COMPLEX. DEEP LOW PRES WILL CONTINUE TO DEEPEN FURTHER OVER ERN CO AND SHOULD BE DOWN TO ~983 MB BY 7PM. A WARM FRONT WILL ORGANIZE AND GRADUALLY LIFT TO NEAR THE NEB-KS BORDER...WITH THE DRYLINE MIXING INTO SW NEB AND WRN KS. INTO TONIGHT THE LOW WILL LIFT INTO THE SANDHILLS...WITH THE WARM FRONT LIFTING FURTHER INTO NEB. BY DAYBREAK TOMORROW...THE PACIFIC COOL FRONT WILL HAVE MERGED WITH THE DRYLINE AND THE OCCLUSION PROCESS WILL BE UNDERWAY OVER NEB. THE LOW WILL REMAIN QUASI-STATIONARY TOMORROW AS THE COMBINED DRYLINE/FRONT PIVOTS CYCLONICALLY NE ACROSS THE FCST AREA FROM 7AM-4PM. A SECONDARY COLD FRONT WILL WRAP CYCLONICALLY AROUND THE LOW FROM 1PM-7PM. THE REST OF THIS AFTERNOON: PARTLY TO MOSTLY CLOUDY. HOT DOWN IN PARTS OF N-CNTRL KS...WHERE STOCKTON WAS 91F AT 3PM. BREEZY SE WINDS...BORDERING ON WINDY. GRI REPORTED A 38 KT GUST AT 240 PM. TONIGHT: WE WILL BE WATCHING FOR AN ISOLATED TSTM OR TWO TO FIRE E OF HWY 281. OTHERWISE...DRY/BREEZY/VERY MILD. USED CONSENSUS OF MODEL 2M TEMPS WHICH KEEPS LOWS IN THE 60S E OF HWY 183. STRATUS IS EXPECTED TO FORM TONIGHT IN VICINITY OF THE WARM FRONT ...AS DEWPOINTS IN THE 50S ADVECT N. SEVERE: THE MESOSCALE BOUNDARIES ARE ORGANIZING. THE PROBLEM LATE THIS AFTERNOON AND TONIGHT WILL BE THE LACK OF LARGE-SCALE FORCING TO SUFFICIENTLY ERODE THE CAP. IT APPEARS PROBABLE THAT NO TSTMS WILL FORM BEFORE SUNSET. THAT DOES NOT MEAN THE PROBABILITY IS ZERO. THERE IS A HINT OF A SMALL COLD FRONT ALOFT CURRENTLY LIFTING NE FROM TX. THIS SUBTLE FEATURE WILL LIFT N THRU THE FCST AREA 7PM-1AM AND THIS COULD PROVIDE THE TRIGGER. BASED ON HI-RES NONHYDROSTATIC MODELS...A SINGLE STORM MAY GO UP AFTER 5 PM SOMEWHERE NEAR I-70 IN CNTRL KS. A COUPLE MORE STORMS COULD JOIN IT FURTHER NE OVER S-CNTRL NEB. AS IT STANDS NOW...THE TSTM THREAT WILL BE PRIMARILY E OF HWY 281. MLCAPE WILL CONTINUE TO INCREASE TO 2500-3000 J/KG AS A SWATH OF DEWPOINTS IN THE 50S LIFTS INTO NEB. DEEP LAYER SHEAR WILL BE SUFFICIENT FOR SUPERCELL CONVECTIVE MODE...ESPECIALLY IN AN ENVIRONMENT WITH WEAK FORCING. ANY SUPERCELLS THAT DEVELOP SHOULD MOVE NE AROUND 15 KTS. ALL THREATS WILL BE POSSIBLE...INCLUDING HAIL TO THE SIZE OF BASEBALLS...DAMAGING WINDS...AND AN ISOLATED TORNADO. AS MIXING WANES THIS EVENING...0-1 KM SHEAR WILL INCREASE TO 30-35 KTS... PUSHING THE 0-1 KM EHI TO 3-5...MORE THAN SUFFICIENT FOR A SIGNIFICANT TORNADO. ANY TSTMS THAT FORM SHOULD BE OUT OF THE FCST AREA BY 10-11 PM. SUN: HIGHLY VARIABLE. WE WILL PROBABLY BE DEALING WITH STRATUS IN SOME AREAS TO START THE DAY. THE STRONGEST QG FORCING WILL OCCUR 7AM-1PM...ALONG WITH A COLD FRONT ALOFT...INTERACTING WITH THE SURFACE BOUNDARIES. SO A NARROW ARC OF TSTMS COULD FORM FAIRLY EARLY AND RACE N INTO THE SANDHILLS. THE EARLIER THE STORMS FORM...THE MORE SEVERE THEY COULD BE. DRY AIR WRAPPING IN FROM THE SW WILL DIMINISH INSTABILITY AS THE DAY WEARS ON. CLEARING SHOULD THEN OCCUR BEHIND THIS LINE...BEFORE ANOTHER BATCH OF CLOUDS MOVES IN BEHIND THE SECONDARY COLD FRONT. THIS COULD TRIGGER A COUPLE SHWRS. SEVERE: DEEP LAYER SHEAR WILL BE EXTREMELY STRONG /50 KTS/ AND STORMS WILL MOVE RAPIDLY N-NNW AT 50-60 MPH. HAIL AS LARGE AS GOLF BALLS AND WIND DAMAGE WILL BE THE PRIMARY THREATS. HOWEVER... ISOLATED TORNADOES WILL BE POSSIBLE...ESPECIALLY WHERE THE COLD AND WARM FRONTS ARE PINCHING TOGETHER AT THE OCCLUSION. WIND: AN ADVISORY WILL BE NEEDED FOR PARTS OF THE FCST AREA S OF I-80. SUSTAINED WINDS MEETING THE CRITERION ARE IN THE FCST. THIS POTENTIAL NEEDS TO BE RE-EVALUATED BY TONIGHT/S MID SHIFT. IN COORDINATING THE DDC/GLD/LBF...DECIDED TO HOLD OFF. WHILE THE GREATEST PRES RISES WILL OCCUR MORE TO THE W...A TROPOSPHERE FOLD COULD RESULT IN ABNORMALLY HIGH MIXING. THE 18Z NAM HAS THE LOOK OF A "PV HOOK" WHICH COULD THREATEN A 1-2 HR PERIOD OF WARNING CRITERIA WINDS /GUST 40+ AND OR GUSTS 58+/. AS FOR FIRE WX...DEWPOINTS WILL NEED TO BE RE-EVALUATED OVER N-CNTRL KS FOR SUN AFTERNOON. AS OF NOW...THE DEWPOINTS SHOULD RISE A BIT BEHIND THE SECONDARY COLD FRONT. SO CURRENT MINIMUM RH VALUES ARE JUST ABOVE 20%. ENOUGH FOR NEAR-CRITICAL MENTION IN THE HWO. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 355 PM CDT SAT APR 26 2014 A BROAD UPPER LEVEL TROUGH IS EXPECTED TO PERSIST ACROSS THE CENTER OF THE CONUS FOR MUCH OF THE UPCOMING WORK WEEK...WITH BELOW NORMAL HEIGHTS ALOFT EXPECTED TO RESULT IN A SEASONABLY COOL END TO THE MONTH OF APRIL AND BEGINNING TO THE MONTH OF MAY. WHILE THE BEST INSTABILITY WILL BE ON THE WANE AS WE WORK THROUGH THE EVENING HOURS ON SUNDAY...EXPECT SOME MODEST INSTABILITY TO PERSIST ACROSS OUR NORTHWEST AS THE MAIN UPPER LEVEL LOW LIFTS NORTH...RESULTING IN AT LEAST THE CHANCE FOR AN ISOLATED THUNDERSTORM ON THE BACKSIDE OF THE ASSOCIATED COLD FRONT. THEREAFTER...EXPECT THE MAIN UPPER LEVEL LOW TO MEANDER ACROSS THE CENTRAL CONUS FOR SEVERAL DAYS...WITH MULTIPLE UPPER LEVEL DISTURBANCES ON THE BACKSIDE OF THE UPPER LEVEL LOW EXPECTED TO ROTATE ACROSS THE REGION. WHILE THERE WILL BE A CHANCE OF SOME LIGHT RAINFALL OFF AND ON AGAIN THROUGH THURSDAY...THE BEST PERIOD FOR MORE WIDESPREAD BENEFICIAL RAINFALL APPEARS TO BE TUESDAY...WHEN A REINFORCING SHOT OF COLD AIR AND MID LEVEL WAVE ADVECT ACROSS THE LOCAL AREA. THIS WILL LIKELY RESULT IN THE COOLEST DAY OF THE EXTENDED...WITH AFTERNOON HIGHS ONLY EXPECTED TO TOP OUT IN THE LOWER 50S TUESDAY AFTERNOON...AND LOWS BOTH WEDNESDAY AND THURSDAY MORNINGS EXPECTED TO DIP INTO THE 30S ACROSS THE MAJORITY OF THE FORECAST AREA. OTHERWISE...THE MAIN STORY TO START OF THE NEW WEEK WILL BE THE WINDS...AS A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF THE SURFACE LOW WILL RESULT IN A VERY WINDY START TO THE WEEK. MODEL GUIDANCE HAS COME UP SIGNIFICANTLY FROM YESTERDAY WITH A DEEPER LOW EXPECTED TO RESULT IN A VERY TIGHT PRESSURE GRADIENT ACROSS THE REGION. ADDITIONALLY...WITH STRONG WINDS ALOFT...EXPECT ANY MIXING DURING THE AFTERNOON HOURS TO RESULT IN STRONG WIND GUSTS ACROSS THE LOCAL AREA BOTH AFTERNOONS...WITH GUSTS TO 40 MPH OR HIGHER NOT OUT OF THE QUESTION. DID NOT INCREASE WINDS TO MATCH SOME OF THE NUMERICAL GUIDANCE...WHICH SUGGESTS 35KT SUSTAINED WINDS ACROSS OUR WEST ON MONDAY AND LIKELY AGAIN TUESDAY...BUT DID REINTRODUCE A MENTION INTO THE HWO...AS IF TRENDS CONTINUE...WE LIKELY WILL EVENTUALLY NEED A WIND ADVISORY HEADLINE FOR AT LEAST THE WESTERN HALF OF THE FORECAST AREA BOTH DAYS. AS THE MAIN UPPER LOW TRANSITIONS INTO THE EASTERN THIRD OF THE CONUS LATE WEEK...EXPECT THE LOCAL AIRMASS TO BEGIN TO MODERATE AS HEIGHTS BUILD ALOFT...RESULTING IN A RETURN TO SEASONAL TEMPERATURES NEAR 70 DEGREES OVER NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1255 AM CDT SUN APR 27 2014 THERE ARE SEVERAL AVIATION CONCERNS INCLUDING THE POSSIBILITY OF IFR CEILINGS THIS MORNING FOLLOWED BY THE POSSIBILITY OF SEVERE THUNDERSTORMS ONCE THE LOW CLOUDS EXIT TO OUR NORTHEAST. THE WIND WILL ALSO BE RATHER GUSTY AT TIMES TODAY PRIMARILY OUT OF THE SOUTHEAST EARLY AND EVENTUALLY OUT OF THE SOUTH LATER THIS AFTERNOON. THERE ARE CURRENTLY NO LOW CLOUDS ANYWHERE NEAR BY KGRI...BUT FORECAST MODELS ARE TRYING TO DEVELOP WIDESPREAD LOW CLOUDS AS WE NEAR DAWN AND BASED ON THE WEATHER PATTERN THIS SEEMS PRETTY REASONABLE. THESE LOW CLOUDS SHOULD PASS OFF TO OUR NORTHEAST BY MID MORNING ALLOWING FOR SUNSHINE AND DESTABILIZATION WITHIN THE WARM SECTOR. KGRI SHOULD BE LOCATED WITHIN THIS WARM SECTOR FROM AROUND MID MORNING THROUGH AS LATE AS MID AFTERNOON WHEN THE DRY LINE WILL EVENTUALLY PASS THROUGH. THIS IS THE WINDOW WHEN THUNDERSTORMS...SOME POSSIBLY SEVERE WILL BE AROUND THE KGRI AREA. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...BRYANT SHORT TERM...HALBLAUB LONG TERM...ROSSI AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1146 PM CDT SAT APR 26 2014 .UPDATE... ISSUED AT 758 PM CDT SAT APR 26 2014 AS EXPECTED...THE 00Z KOAX INDICATED A HEALTHY CAP ACROSS THE REGION...AND THIS LIKELY PREVENTED STORMS FROM DEVELOPING IN SOUTH CENTRAL NEBRASKA. ALTHOUGH THEY DID TRY AROUND 4 TO 6 PM WITH A COUPLE OF CU CLOUDS TRYING TO DEVELOP ALONG THE WARM FRONT AND SOME CLOUD TOP COOLING INDICATED IR IMAGERY...BUT IT FIZZLED. RECENT RUNS OF THE RAP/HRRR HAVE NOT GIVEN UP ON THE CONVECTIVE INITIATION THOUGH IN THAT AREA...DESPITE NOTHING HAPPENING THUS THE MODELS ARE LIKELY OVERDOING ANY CONVECTIVE DEVELOPMENT TONIGHT. 00Z UPPER AIR ANALYSIS REVEALED THAT THE HEIGHT FALLS FROM THE SOUTHWESTERN TROUGH WERE FINALLY STARTING TO FILTER ONTO THE PLAINS...WITH 10 METER HEIGHT FALLS AT KOMA AND 40 TO 60 METER HEIGHT FALLS ACROSS THE WESTERN HIGH PLAINS. 700 MB TEMPS WERE +8 TO +10 ACROSS MOST OF THE PLAINS. AT THE SURFACE...A WARM FRONT EXTENDED EASTWARD FROM THE LOW ACROSS NORTHEAST CO...EAST SOUTHEAST INTO NORTHEASTERN KANSAS. FOR THE FORECAST OVERNIGHT...WE HAVE MAINTAINED JUST 20 PERCENT CHANCE POPS FOR SOMETHING DEVELOPING NORTH OF THE WARM FRONT WITH WEAK HEIGHT FALLS ALOFT AND POSSIBLE SLIGHT STRENGTHENING OF THE LOW LEVEL JET. THIS IS GENERALLY ALONG/NORTH OF I80...WITH SLIGHT CHANCES SHIFTING NORTH/NORTHEAST THROUGH THE NIGHT. BUT THE FOCUS COULD VERY WELL BE JUST A BIT FURTHER NORTH OF OUR FORECAST AREA ALONG THE 850 MB FRONTAL BOUNDARY INTO SOUTHEAST SD AND NORTHWEST IOWA...KEEPING MOST OF THE FORECAST AREA DRY. THIS IS ALSO IN LINE WITH THE LATEST 01Z SPC DAY 1 OUTLOOK...SHIFTING THE SLIGHT RISK INTO OUR FAR NORTHEASTERNMOST COUNTIES. THERE DOES STILL APPEAR TO BE ANOTHER IMPULSE THAT WILL MOVE INTO THE AREA FROM NORTHEAST KANSAS SUNDAY MORNING THAT THEN ROTATES NORTHWEST INTO THE FORECAST AREA. && .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 322 PM CDT SAT APR 26 2014 STORM SYSTEM IS DEEPENING AND BEGINNING TO AFFECT THE PLAINS. SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES DEEPENING 500MB TROUGH IN THE WESTERN US...WITH 500MB HEIGHT FALLS UP TO 170M CENTERED IN THE CA/NV/AZ BORDER REGION...AND WITH SOUTHWESTERLY UPPER-LEVEL FLOW ACROSS THE CENTRAL US. 300MB JET UP TO 130KT WAS STILL ON THE WEST SIDE OF THE TROUGH...WITH 105-115KT AROUND THE BASE AND TOWARD THE EAST OF THE TROUGH AXIS. 850MB MOISTURE AT 12Z WAS FOCUSED IN TWO SEPARATE AREAS...ONE RIGHT ALONG THE GULF COAST...AND FROM WEST TX THROUGH OK INTO SOUTHWEST MO...WITH 850MB WINDS UP TO AROUND 50KT TRANSPORTING MOISTURE NORTHWARD INTO THE CENTRAL PLAINS. WEAK 850MB FRONT WAS NOTED FROM LOW IN NORTHERN WY/SOUTHERN MT THROUGH NEB INTO NORTHERN MO. 700-500MB DELTA-T OF 20-24C WAS NOTED ACROSS THE PLAINS...WITH THE HIGHEST VALUES ALONG THE HIGH PLAINS TOWARD OK/WEST TX. SURFACE LOW AT 19Z WAS CENTERED IN NORTHEAST CO...WITH WIND SHIFT WARM FRONT EXTENDING ACROSS NEB NEAR THE PLATTE RIVER TOWARD WEST CENTRAL TO SOUTHEAST IA...AND WITH MOISTURE GRADIENT NEAR THE KS/NE BORDER AS UPPER 50S DEWPOINTS HAD ADVANCED INTO NORTHEAST TO CENTRAL KS. MAIN FORECAST CONCERN IS VERY CONDITIONAL CONVECTIVE POTENTIAL THIS EVENING...CONVECTION ON CWA MARGINS TONIGHT...AND MORE WIDESPREAD CONVECTIVE POTENTIAL TOMORROW. RAP CONTINUES TO MIX OUT PROFILE DEEPLY BY 23-00Z AND DEVELOP VERY HIGH-BASED CONVECTION...WHILE HRRR HAS TRENDED FROM PRODUCING A CELL OR TWO THIS EVENING TO NEARLY DRY...AND 12Z 4KM WRF KEPT THE AREA MAINLY DRY THROUGH TONIGHT. MODELS THAT DO PRODUCE SOME CONVECTION LATER TONIGHT ARE DOING SO JUST IN OUR NORTHEASTERNMOST CWA. HAVE KEPT A VERY LOW-CONFIDENCE SMALL AREA OF POPS ADVANCING FROM SOUTHEAST NEB TO NEAR THE I-80 CORRIDOR IN THE EARLY EVENING...THEN SLIGHT CHANCES IN THE NORTHERN CWA THE REST OF THE EVENING BEFORE FOCUSING ON THE NORTHEASTERNMOST FRINGE FOR TONIGHT. AS UPPER LOW EJECTS ACROSS THE ROCKIES TOWARD KS/NEB ON SUNDAY...WITH INCREASING MOISTURE TRANSPORT INTO THE CENTRAL PLAINS...SHOULD SEE CONVECTION DEVELOP BY MIDDAY IN EASTERN NEB...SPREADING INTO WESTERN IA QUICKLY. WITH ABUNDANT SHEAR ACROSS THE AREA...POTENTIAL FOR SEVERE WEATHER DOES EXIST FOR ANY CONVECTION AS IT GETS GOING ACROSS THE AREA FROM MIDDAY THROUGH THE AFTERNOON. ALSO...AM THINKING THAT THERE WILL BE ENOUGH OF A BREAK IN CONVECTION TONIGHT THROUGH MUCH OF THE MORNING THAT AIRMASS WILL HAVE TIME TO SUFFICIENTLY DESTABILIZE AT LEAST IN THE SOUTHERN HALF OF THE CWA IF NOT ACROSS THE ENTIRE CWA. WITH SUCH STRONG UPPER- LEVEL SUPPORT THOUGH...CONVECTION WILL BE QUITE WIDESPREAD...AND THUS CONVECTIVE MODE/THREATS WILL BE MESSY AND COMPLICATED. WITH VERY STRONG DEEP-LAYER SHEAR...ROTATING LARGE HAIL WILL BE A THREAT...AS WELL AS POTENTIAL FOR DAMAGING WIND GUSTS. ENOUGH 0-1KM SHEAR EXISTS FOR A TORNADO THREAT FOR STORMS IF THEY CAN STAND ALONE...THOUGH WORTH NOTING THAT HODOGRAPHS ARE MORE STRAIGHT THAN CURVED IN MOST MODEL SOLUTIONS. STORMS WILL MOVE FAIRLY RAPIDLY TOWARD THE NORTH-NORTHEAST...AND AS THE SURFACE LOW PUSHES EASTWARD...SHOULD EXIT THE CWA THROUGH THE LATE AFTERNOON TO EARLY EVENING HOURS...LEAVING CWA IN DRY SLOT FOR THE REST OF THE NIGHT AND THROUGH MUCH OF MONDAY. ONCE UPPER LOW ADVANCES INTO NEB...IT IS PROGGED TO STALL THROUGH MONDAY...THEN FILL AND DRIFT EASTWARD INTO IOWA ON TUESDAY. PRECIPITATION WILL RETURN TO THE CWA IN THE WRAPAROUND AREA BEGINNING LATE MONDAY...EXPANDING ACROSS THE CWA THROUGH MONDAY NIGHT AND TUESDAY...WITH AT LEAST OCCASIONAL LIGHT PRECIPITATION CONTINUING THROUGH THURSDAY AS CWA REMAINS IN COOL CYCLONIC FLOW BEHIND THE UPPER LOW. REMOVED THUNDER MENTION FROM ANY PRECIPITATION FROM MONDAY EVENING ONWARD...AS AIRMASS REALLY STABILIZES ON THE COLD SIDE OF THE LOW. TEMPERATURES WILL BE MUCH COOLER BEHIND THE LOW...WITH TEMPERATURES ON MONDAY DOWN INTO THE 50S AND LIKELY STRUGGLING TO EVEN REACH 50 ON TUESDAY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 322 PM CDT SAT APR 26 2014 GENERALLY COOLER AND UNSETTLED WEATHER PATTERN WILL CONTINUE THROUGH NEXT WEEKEND. HAVE KEPT SPECIFIC POP MENTIONS OUT OF MOST PERIODS FOR NOW...BUT THINK THERE IS A DECENT CHANCE TO GET AT LEAST LIGHT PRECIPITATION IN AT LEAST SOME PART OF THE CWA ON SOME PERIOD. FOR NOW...HAVE INCREASED CLOUDS A BIT. ALSO KEPT TEMPERATURES ON THE COOL SIDE...WITH TEMPERATURES CONTINUING IN THE 50S THROUGH THURSDAY BEFORE POSSIBLY REBOUNDING INTO THE 60S IN AT LEAST PART OF THE AREA BY FRIDAY OR SATURDAY. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1142 PM CDT SAT APR 26 2014 STILL A FAIRLY COMPLEX AVIATION FORECAST. INITIALLY...VFR CONDITIONS WITH STRONG SOUTHEASTERLY WINDS AT 18 TO 22 KNOTS...GUSTING UP TO 25 TO 30 KNOTS. MVFR CLOUDS ARE STILL EXPECTED TO DEVELOP THROUGH THE NEXT FEW HOURS...BY 09-10Z ACROSS THE REGION. IN ADDITION... THUNDERSTORMS WILL BE POSSIBLE AS HEIGHT FALLS FROM THE UPPER LEVEL TROUGH TO OUR WEST BEGIN TO MOVE INTO THE AREA BY 13-15Z. AFTER THE MORNING CONVECTION...THERE WILL LIKELY BE A BREAK IN THUNDERSTORM ACTIVITY...WITH REDEVELOPMENT OF STRONGER THUNDERSTORMS IN THE MID TO LATE AFTERNOON THAT COULD LINGER THROUGH EARLY EVENING AS A DRY LINE MOVES INTO THE REGION. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DEWALD SHORT TERM...MAYES LONG TERM...MAYES AVIATION...DEWALD
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1138 PM CDT SAT APR 26 2014 .SYNOPSIS... ISSUED AT 358 PM CDT SAT APR 26 2014 AT 19Z...WATER VAPOR IMAGERY SHOWED A DEEP UPPER LEVEL TROUGH ACROSS THE WESTERN CONUS...WITH A STRONG PV ANOMALY AT THE BASE OF THE TROUGH OVER WESTERN ARIZONA. UPPER LEVEL ANALYSIS FROM 12Z SHOWED 100+KT JET ROUNDING THE BASE OF THE TROUGH. DOWNSTREAM OF THE TROUGH...THE RIDGE AXIS WAS FROM THE LOWER MISSISSIPPI RIVER VALLEY...INTO THE NORTHERN PLAINS AND UP INTO THE WESTERN NORTHWEST TERRITORIES IN CANADA. AT THE SURFACE...LOW PRESSURE WAS OVER NORTHERN COLORADO WITH A WARM FRONT EXTENDING ACROSS NORTHERN KANSAS. SOUTH OF THE WARM FRONT TEMPERATURES HAD WARMED INTO THE UPPER 80S AND LOW 90S ALONG WITH BREEZY SOUTHERLY WINDS AND A GOOD DRYLINE FROM EAST OF KHLC INTO THE OKLAHOMA PANHANDLE. TO THE NORTH OF THE FRONT 70S AND LOW 80S WERE OBSERVED WITH SOUTHEAST WINDS. FURTHER NORTH...A STATIONARY FRONT WAS LOCATED FROM WESTERN SOUTH DAKOTA INTO EAST CENTRAL NEBRASKA WITH A SLIGHT WIND SHIFT BEING DEFINED IN THE SURFACE FIELD. WINDS NORTH OF THE FRONT WERE QUITE STRONG...WITH GUSTS OF 35KTS TO 50KTS ACROSS SOUTH DAKOTA. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 358 PM CDT SAT APR 26 2014 THE UPPER LEVEL TROUGH WILL LIFT INTO SOUTHEAST COLORADO BY 12Z SUNDAY. MEANWHILE...THE WARM FRONT WILL LIFT NORTH THIS EVENING AS THE SURFACE LOW SLOWLY MIGRATES EAST INTO SOUTHWEST NEBRASKA. CURRENTLY...THE AREA IS IN THE DRY SLOT OF THE MID LEVEL FLOW AS CAN BE SEEN FROM WATER VAPOR AS THE FETCH OF DRY AIR COMES ALL THE WAY INTO NEBRASKA FROM THE BASE OF THE TROUGH. THE MAIN AREA OF MOISTURE IS BEING PUSHED INTO KANSAS AND EASTERN NEBRASKA AS CAN BE SEEN BY MID LEVEL CLOUD COVER. THIS DRY AIR WILL KEEP ANY SHOWERS/STORMS FROM DEVELOPING NORTH OF THE WARM FRONT YET THIS AFTERNOON. AS THE FRONT MOVES NORTH THE AREA THIS EVENING...MODELS SHOW THE WARM SECTOR STAYING CAPPED AT LEAST UNTIL 00Z AND MUCH OF THE LOCAL AREA STAYING CAPPED UNTIL AFTER 06Z. THE LATEST HRRR FROM 26.18Z DOES SHOW A FEW STORMS DEVELOPING OVER EASTERN NEBRASKA AROUND 00Z. BUT WITH THE MID LEVEL FLOW...ANYTHING THAT DEVELOPS WILL MOVE QUICKLY NORTHEAST. IF THE FORECAST AREA WILL SEE ANY STORMS TONIGHT...WILL NEED STORMS TO DEVELOP LOCALLY. DIDN/T REMOVE CHANCES COMPLETELY OVERNIGHT...BUT CONFIDENCE IS NOT HIGH ON STORM DEVELOPMENT. IF STORMS WOULD DEVELOP THIS EVENING ALONG THE WARM FRONT...SEVERE PARAMETERS DO INDICATE THERE WOULD BE POTENTIAL FOR A FEW ORGANIZED SUPERCELLS. AND WITH GOOD LOW LEVEL HELICITY...CAN/T COMPLETELY RULE OUT A BRIEF ISOLATED TORNADO. HOWEVER...EVEN THOUGH SOUTHEAST AND EASTERLY WINDS ALONG THE WARM FRONT WILL CONTINUE TO PULL MOISTURE INTO NORTH CENTRAL NEBRASKA THIS EVENING AND OVERNIGHT. HOWEVER...THINK SOME OF THE MODELS MAY BE A BIT ROBUST GETTING MID TO UPPER 50 DEWPOINTS IN THESE AREAS. THE LACK OF LOW LEVEL MOISTURE WOULD VERY LIKELY PROHIBIT ANY STORMS PRODUCING TORNADOS. FOR SUNDAY...THE MODELS ARE FINALLY COMING INTO AGREEMENT ON THE TRACK OF THE SYSTEM AS THEY BRING THE 500MB LOW INTO WESTERN NEBRASKA. THERE DOES REMAIN SOME DIFFERENCES THOUGH IN THE WEST TO EAST EXTENT AND ALTHOUGH IT IS NOT MUCH IT HAS A HIGH IMPACT ON THE WEATHER FOR SUNDAY AND SUNDAY NIGHT. FORECAST CONFIDENCE HAS IMPROVED...YET THERE ARE STILL CONSIDERABLE QUESTIONS. WITH THE SURFACE LOW NOW LOOKING MORE LIKELY TO TRACK JUST NORTH OF THE NEBRASKA-KANSAS BORDER SUNDAY AND CENTERED IN THE KLBF/KMCK AREA AT 00Z PRECIPITATION CHANCES WILL INCREASE THROUGH THE DAY...MAINLY ON THE NORTHERN AND WESTERN PERIPHERIES OF THE LOW. SO DID INCREASE CHANCES ACROSS NORTHERN NEBRASKA AND THE PANHANDLE. ON THE BACK SIDE OF THE LOW...WINDS WILL STRENGTHEN CONSIDERABLY BY LATE AFTERNOON. CURRENT FORECAST FOLLOWS A SLOWER EASTERLY PROGRESSION OF THE SURFACE LOW WHICH KEEPS THE WINDS FROM INCREASING UNTIL AFTER 00Z. HOWEVER QUICKER MOVEMENT COULD MEAN STRONG WINDS OF 30KTS SUSTAINED EARLIER. WILL LET ONE MORE FORECAST CYCLE GO TO ALLOW MODELS TO COME INTO BETTER AGREEMENT BEFORE DECIDING ON ANY HEADLINES FOR WINDS DUE TO SOME UNCERTAINTY. IN TERMS OF THUNDERSTORMS FOR SUNDAY...INSTABILITY ISN/T TERRIBLY HIGH...WITH MUCAPE VALUES OF 100J/KG TO 1500 J/KG...BUT WITH STEEP LOW LEVEL LAPSE RATES AND SUFFICIENT SHEAR CAN/T DISCOUNT ANY STORMS AS WELL AS ANY STORMS BECOMING SEVERE. THE PRIMARY AREAS OF CONCERN WILL BE OVER NORTH CENTRAL NEBRASKA /EAST OF HIGHWAY 183/ WHERE THERE WILL BE MORE MOISTURE. SOMETHING TO CONSIDER WATCHING THROUGH THE DAY WILL BE IF ANY CONVECTION GOES UP ON THE WESTERN EDGE OF THE SURFACE LOW AND THE INVERTED TROUGH ACROSS THE WESTERN SANDHILLS. THERE IS ONLY LOW INSTABILITY BUT WITH LOW LEVEL TURNING IN THE VICINITY OF THE BOUNDARY...COULD CAUSE ANY CONVECTION TO SPIN. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 358 PM CDT SAT APR 26 2014 MID RANGE...SUNDAY NIGHT THROUGH TUESDAY...A PERSISTENT...SLOW MOVING UPPER LEVEL LOW...WILL MEANDER FROM SOUTHWESTERN TO NORTHEASTERN NEBRASKA DURING THE PERIOD...EVENTUALLY MOVING EAST OF THE STATE TUESDAY NIGHT. A PLETHORA OF WEATHER WILL OCCUR ON THE BACK SIDE OF THIS FEATURE AS IT MIGRATES ACROSS WESTERN AND NORTH CENTRAL NEBRASKA SUNDAY NIGHT INTO TUESDAY AND THIS WILL BE THE MAIN FORECASTING CHALLENGE FOR THE BEGINNING OF THE WEEK. SUNDAY NIGHT INTO MONDAY...FOR THESE PERIODS...THE THREAT FOR WINTRY WEATHER IN THE NORTHWEST SUNDAY NIGHT THEN WIND POTENTIAL SUNDAY NIGHT INTO MONDAY ARE THE MAIN FORECAST CONCERNS. SUNDAY NIGHT INTO MONDAY...AN INTENSE UPPER LEVEL LOW AND STRONG SURFACE LOW...WILL MEANDER SLOWLY ACROSS NEBRASKA. ON THE BACK SIDE OF THIS FEATURE SUNDAY NIGHT INTO MONDAY...A NICE DEFORMATION BAND OF PCPN IS EXPECTED TO DEVELOP ALONG WITH STRONG WINDS WHICH WILL TRANSITION FROM WEST TO EAST SUNDAY NIGHT INTO MONDAY. HOW FAR EAST THE STRONG WINDS DEVELOP SUNDAY NIGHT INTO MONDAY IS STILL UP IN THE AIR SOME. MORE ON THAT TWO PARAGRAPHS BELOW. EVEN AT ONLY 36 TO 48 HOURS OUT...THE LATEST NAM...GFS AND ECMWF SOLNS ARE STILL HAVING ISSUES WITH THE TRACK OF THE H5 LOW AND TRACK OF THE SURFACE LOW. THE NAM LIFTS THE H5 LOW FROM AROUND ARNOLD NEBRASKA TO NORTH OF ONEILL NEBRASKA FROM 00Z TO 12Z MONDAY. THE GFS LIFTS THE LOW FROM FAR EASTERN FRONTIER COUNTY TO NEAR SPRINGVIEW NEBRASKA DURING THE SAME PERIOD...WHILE THE ECMWF LIFTS THE LOW FROM WESTERN LINCOLN COUNTY TO NEAR VALENTINE. NO SURPRISE...THE NAM IS COLDEST AT H85 WITH SUB FREEZING TEMPS IN THE NORTHWESTERN FORECAST AREA OVERNIGHT SUNDAY NIGHT...WHICH WOULD FAVOR SNOW FOR PRECIPITATION TYPE. THE GFS AND ECMWF ARE CONSIDERABLY WARMER WITH H85 TEMPS OF 2 TO 3 C AT 12Z MONDAY MORNING...FAVORING ALL RAIN OR POSSIBLE RAIN SNOW MIX. ATTM...WILL GO WITH A RAIN/SNOW MIX FOR PTYPE OVERNIGHT SUNDAY NIGHT IN THE FAR NORTHWEST GIVEN THE TRACK DIFFERENCES IN THE UPPER LEVEL SYSTEM. ATTM...WITH TEMPERATURES HOVERING IN THE MIDDLE 30S SUNDAY NIGHT IN THE FAR NORTHWEST...NOT EXPECTING ANY ACCUMS ATTM. THEN THERE IS THE WIND THREAT ON THE BACK SIDE OF THE EXITING SYSTEM. FOR SUNDAY NIGHT...THE ECMWF AND GFS SOLNS ARE IN GENERAL AGREEMENT WITH LOCATION OF THE SURFACE LOW AT 12Z MONDAY...IE OVER THE FAR NERN CWA...WHILE THE NAM12 HAS THE LOW NEAR SIOUX CITY IOWA. NO SURPRISE...THERE ARE SIGNIFICANT DIFFERENCES IN WIND SPEEDS BETWEEN THE MET AND MAV GUIDANCE FOR SUNDAY NIGHT. IF THE MET VERIFIES...WE WOULD PROBABLY NEED SOME SORT OF WIND HEADLINE FOR AT LEAST THE WESTERN HALF OF THE FORECAST AREA SUNDAY NIGHT. WITH THE GFS SOLN...ANY WIND ADVISORY IF NEEDED WOULD BE CONFINED TO THE FAR SOUTHWESTERN AND EASTERN PANHANDLE COUNTIES. THIS LEADS TO THE HEADLINE DILEMMA FOR SUNDAY NIGHT...WINTER HEADLINES IN THE NERN PANHANDLE OR WIND HEADLINES. GIVEN THE DISCREPANCIES IN THE LOCATION OF THE SURFACE LOW AND UPPER LEVEL LOW...WILL HOLD OFF ON HEADLINES FOR SUNDAY NIGHT AND WAIT FOR ANOTHER MODEL RUN TO COME IN. ON MONDAY...THE SURFACE LOW WILL MIGRATE EAST OF THE UPPER LEVEL LOW INTO EASTERN NEBRASKA. AT THE SAME TIME...A DOWNSTREAM BLOCKING RIDGE WILL LIMIT ANY EWD MOVEMENT OF THE H5 LOW...WHICH WILL REMAIN IN PLACE ACROSS CENTRAL NEBRASKA. WRAP AROUND PCPN WILL CONTINUE PARTICULARLY OVER NORTH CENTRAL AND NORTHWESTERN NEBRASKA AS FAVORABLE ISENTROPIC LIFT CONTINUES. IN ADDITION TO COLD RAIN...VERY WINDY CONDITIONS WILL DEVELOP ESPECIALLY ACROSS THE WESTERN 2/3RDS OF THE FORECAST AREA. AGAIN...LIKE SUNDAY NIGHT...WIND SPEEDS WILL BE HIGHLY DEPENDENT ON WHERE THE SURFACE LOW SETS UP ON MONDAY AFTERNOON. BETTER CONFIDENCE EXISTS IN THE WIND FORECAST FOR MONDAY AS THE MODELS HAVE THE SURFACE LOW OVER NERN NEBRASKA BY 00Z TUESDAY. MONDAY NIGHT AND TUESDAY...FROM MONDAY NIGHT INTO TUESDAY AFTERNOON...THE UPPER LEVEL LOW WILL CRAWL SLOWLY EAST INTO THE MID MISSISSIPPI VALLEY. ON MONDAY NIGHT...A STRONG SHORTWAVE WILL ROTATE AROUND THE WESTERN PERIPHERY OF THE CLOSED LOW BRINGING ANOTHER SHOT OF RAIN AND OR SNOW SHOWERS TO THE FORECAST AREA. THE LATEST ECMWF AND GFS SOLNS ARE INDICATING ENOUGH COLD AIR FOR AT LEAST A RAIN SNOW MIX OVERNIGHT MONDAY NIGHT INTO TUESDAY MORNING ACROSS PORTIONS OF NORTH CENTRAL NEBRASKA AND WILL INSERT THIS IN THE UPDATED FORECAST. WINDS WILL BE AN ISSUE ONCE AGAIN ON TUESDAY 40+ KT H85 WINDS WILL BE PRESENT ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. TEMPERATURES TUESDAY WILL BE COOLER AS WELL AND IS SHAPING UP TO BE THE COOLEST DAY OF THE PERIOD ACROSS WESTERN AND NORTH CENTRAL NEBRASKA AS H85 TEMPS DROP DOWN TO -2C TO 5C. ACROSS NORTH CENTRAL NEBRASKA...TEMPERATURES WILL BE COOL ENOUGH TO FACILITATE AT LEAST A RAIN SNOW MIX TROUGH THE MORNING HOURS AND WILL INCLUDE THIS MENTION IN THE FORECAST. TUESDAY NIGHT AND BEYOND...UPPER LOW PRESSURE WILL MEANDER OVER EASTERN IOWA BEFORE LIFTING INTO THE WESTERN GREAT LAKES ON THURSDAY INTO THURSDAY NIGHT. THE THREAT FOR LIGHT PRECIPITATION WILL CONTINUE THROUGH THURSDAY WITH A LIMITED CHANCE FOR RAIN OR SNOW OVER NORTHERN NEBRASKA DURING THE OVERNIGHT AND EARLY MORNING HOURS. WILL KEEP POPS SLIGHT AS MOISTURE WILL BE FAIRLY LIMITED AS WE HEAD INTO THE MIDDLE AND END OF THE WEEK. TEMPERATURES WILL SLOWLY MODERATE INTO THE 50S FOR WEDNESDAY AND THURSDAY...APPROACHING THE LOWER 60S FOR FRIDAY AND SATURDAY AS THE UPPER LEVEL LOW IS ABSORBED BY THE NRN STREAM AND LIFTED INTO EASTERN CANADA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1137 PM CDT SAT APR 26 2014 VFR IS EXPECTED MOST AREAS OVERNIGHT TONIGHT. THERE IS THE POTENTIAL FOR STRATUS TO DEVELOP ACROSS NRN NEB SUNDAY MORNING IN A BELT OF STRONG EAST WINDS. THE MODELS ARE WOBBLING WITH THIS FEATURE SO CONFIDENCE IS LOW. TSTM CHANCES SHOULD INCREASE MARKEDLY FROM 15Z SUNDAY ONWARD AS AN UPPER LEVEL DISTURBANCE...CURRENTLY CROSSING NEW MEXICO...LIFTS NORTH THROUGH THE FCST AREA. THROUGHOUT THE DAY...RAIN CHANCES SHOULD INCREASE ACROSS WRN NEBRASKA WITH THE APPROACH OF A STRONG PACIFIC COLD FRONT CURRENTLY MOVING THROUGH NM...COLO AND WY. THIS FRONT SHOULD MARK THE BEGINNING OF MVFR/IFR CIGS IN RAIN AND LOW CLOUDS. THE FRONT WILL MOVE SLOWLY EAST SUNDAY NIGHT WITH FLIGHT CONDITIONS WORSENING ACROSS NCNTL NEBRASKA SUNDAY EVENING. && .FIRE WEATHER... ISSUED AT 908 PM CDT SAT APR 26 2014 THE LOSS OF DAYTIME HEATING HAS CAUSED WIND SPEEDS TO DROP TO 10 MPH OR LESS. THE THREAT OF CRITICAL FIRE DANGER HAS ENDED AND THE RED FLAG WARNING FOR FRENCHMAN BASIN HAS BEEN CANCELLED. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BROOKS SHORT TERM...BROOKS LONG TERM...CLB AVIATION...CDC FIRE WEATHER...CDC
AREA FORECAST DISCUSSION...CORRECTED
NWS WILMINGTON NC
929 PM EDT MON APR 28 2014 .SYNOPSIS... UNSETTLED WEATHER WILL PERSIST OVER THE NEXT COUPLE OF DAYS. SHOWERS AND THUNDERSTORMS ARE EXPECTED INCREASE IN COVERAGE THROUGH WEDNESDAY AS A TROUGH OF LOW PRESSURE APPROACHES FROM THE WEST. ANOTHER QUICK ROUND OF RAIN IS POSSIBLE LATE FRIDAY AND SATURDAY BEFORE CONDITIONS DRY OUT INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 645 PM MONDAY...A CLUSTER OF STRONG TO SEVERE THUNDERSTORMS DEVELOPED ALONG A STATIONARY FRONT ACROSS SOUTHERN NORTH CAROLINA A FEW HOURS AGO. SUBJECTIVE SURFACE ANALYSIS SHOWED SIGNIFICANT BACKING OF THE LOW- LEVEL WIND ACROSS THE COASTAL PLAIN OF NC WHILE MODIFIED 18Z MODEL SOUNDINGS INDICATED CAPE AS HIGH AS 2700 J/KG EARLIER. MULTI CELL STORMS DEVELOPED BUT DID NOT DISPLAY SIGNIFICANT DEVIANT MOTION AS THEY MIGHT HAVE HAD SUPER CELLS DEVELOPED. STILL... HIGH REFLECTIVITY CORES REACHED INTO COLD ENOUGH LAYERS OF THE ATMOSPHERE TO LEAD US TO BELIEVE LARGE HAIL WAS A SIGNIFICANT THREAT. IF YOU OBSERVED HAIL OR WIND DAMAGE ACROSS ROBESON OR BLADEN COUNTIES THIS EVENING PLEASE LET US KNOW! THE FRONT SHOULD REMAIN NEARLY STATIONARY ACROSS SOUTHERN NORTH CAROLINA THIS EVENING...MAINLY JUST NORTH OF LUMBERTON AND ELIZABETHTOWN ARCING NORTHEASTWARD TOWARD NEW BERN ALONG THE COAST. THIS WILL LEAVE OUR FORECAST AREA IN A WARM AND HUMID TROPICAL AIRMASS WITH DEWPOINTS AND LOW TEMPERATURES FORECAST TO BE IN THE UPPER 60S. THE 500 MB RIDGE AXIS THAT HAS HELPED TO SUPPRESS PRECIPITATION OVER THE PAST FEW HOURS WILL FINALLY PUSH OFFSHORE LATE TONIGHT...AND THERE IS THE POTENTIAL FOR A REDEVELOPMENT OF AT LEAST ISOLATED SHOWERS/T-STORMS JUST BEFORE DAYBREAK AS WIND VECTORS BECOME DIFLUENT ALOFT AND THE 850 MB WIND BACKS AND STRENGTHENS. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... INCREASINGLY WARM AND MORE UNSTABLE AIR MASS WITH TEMPS INTO THE 80S MOST PLACES. MODELS STILL SHOW MID TO UPPER RIDGE LINED UP THE SOUTHEAST COAST WHICH SHOULD HELP TO INHIBIT SOME OF THE STRONGEST CONVECTION RUNNING SOUTH...BUT AS TEMPS WARMED INTO THE 80S AND DEWPOINTS INTO THE MID 60S CLOSER TO 70 OVER SOUTH CAROLINA. HRRR AND RUC SHOWING BEST CAPE LINED UP INLAND FROM SOUTH TO NORTH TOWARD DARLINGTON AND MARLBORO...BUT MAIN FOCUS OF STRONGER CONVECTION WILL BE ALONG THE LINGERING FRONTAL BOUNDARY JUST TO THE NORTH OF LOCAL FORECAST AREA. EXPECT SCT CONVECTION OVER THE AREA WITH MAIN FOCUS ALONG SEA BREEZE CONVERGENT BOUNDARY AND RUNNING ALONG LINGERING FRONTAL BOUNDARY. JUST NORTH OF BOUNDARY STILL SEEING TEMPS NOT EVEN REACHING 70 WITH COOLER AIR WEDGED IN. BEST HELICITY WILL RUN ALONG WARM FRONT WITH VALUES ABOVE 200 JUST TO NORTH. OVERALL SHOULD BE RATHER FINE BOUNDARY OF STRONGEST STORMS AS FORCING REMAINS WEAKER FARTHER SOUTH DUE TO INCREASED SUBSIDENCE WITH MID TO UPPER RIDGE OVER THE SOUTHEAST COAST. OVERALL THREAT OF HAIL AND STRONG WINDS WITH ANY STORMS THAT MAY REACH INTO OUR NORTHERN TIER COUNTIES. THE STEERING FLOW WILL PUSH ANY SHWRS/TSTMS THAT DEVELOP TOWARD THE COAST BUT THE MORE STABILIZED AIR BEHIND SEA BREEZE SHOULD KEEP THE IMMEDIATE COAST FREE OF STORMS. KEPT POPS VERY CLOSE TO PREVIOUS FORECAST WITH ONLY MINOR ADJUSTMENTS AND WILL UPDATE AS NEEDED ONCE CONVECTION FLARES. SHOULD SEE A FAIR AMOUNT OF CLOUDS AS CONVECTIVE DEBRIS CLOUDS WILL BE STEERED EAST MIXED WITH CU FIELD ACROSS THE AREA. THE STALLED BOUNDARY WILL BEGIN TO LIFT NORTH THROUGH TONIGHT AND EXPECT LOCALIZED CONVECTION TO SHUT DOWN AS HEATING OF THE DAY CUTS OFF AFTER SUNSET. THEREFORE WILL TAPER OFF POPS AFTER SUNSET LEAVING BEST CHC TO THE NORTH ALONG BOUNDARY. SHOULD BE A RELATIVELY QUIET NIGHT WITH LOWS WELL ABOVE CLIMO...RUNNING IN THE MID 60S IN A WARM AND HUMID AIRMASS. && .SHORT TERM /6 AM TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 PM MONDAY...ATTENTION THROUGHOUT THE ENTIRE FORECAST PERIOD WILL FOCUS ON UNSETTLED WEATHER...INCLUDING THE THREAT FOR SEVERE WEATHER JUST AHEAD OF AN APPROACHING COLD FRONT. LATEST GUIDANCE CONTINUES TO ILLUSTRATE A LONGWAVE TROUGH ACROSS THE CONUS WITH A PERSISTENT UPPER LEVEL LOW WHICH WILL SLOWLY PROGRESS ACROSS THE MIDWEST OVER THE NEXT COUPLE OF DAYS. WARM TEMPERATURES AND SOUTHWEST FLOW WILL ALLOW FOR A MOISTURE-RICH ATMOSPHERE...AS DEWPOINTS ARE WELL IN THE 60S...TO REMAIN IN PLACE WITH HIGHS ON TUESDAY IN THE LOWER 80S ACROSS THE ENTIRE FORECAST AREA. SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGHOUT THE DAY ON TUESDAY WHICH IS IN GOOD AGREEMENT AS OUR AREA IS INCLUDED IN SPC`S SLIGHT RISK. INTO WEDNESDAY...CONDITIONS WILL CONTINUE TO PROGRESS IN INCREASE...AS IT LOOKS THE BETTER INSTABILITY AND LIFT WILL MOVE INTO THE CENTRAL SC/NC/VA AREA...WITH A HEIGHTENED POSSIBILITY OF SEVERE ESPECIALLY IN OUR WESTERN ZONES. DIFFICULTY WILL BE TIMING AS MODELS HAVE EVER SO SLIGHTLY SLOWED DOWN THE PROGRESSION OF THE SYSTEM IN PAST RUNS. HOWEVER...OVERALL ANTICIPATE MAIN THREAT TO OCCUR WEDNESDAY THROUGHOUT THE DAY WITH AMPLE DIURNAL HEATING WITH HIGHS ON WEDNESDAY AGAIN IN THE 80S...INTO EARLY THURSDAY MORNING. WILL ALSO TAKE INTO ACCOUNT THE INTERACTION OF THE SEA BREEZE AS WELL ON BOTH DAYS AND ANY OTHER WANDERING BOUNDARIES ABOUT THE AREA. THE PRIMARY THREATS WILL BE HAIL AND DAMAGING WINDS...ALONG WITH THE POSSIBILITY OF TORNADOES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...THURSDAY MAY BE RATHER ACTIVE. THE UPPER RIDGE AXIS WILL BE OFFSHORE ALLOWING FOR DEEP SWRLY FLOW. SURFACE BOUNDARY AND UPPER LEVEL VORT MAXES MAY SPONSOR DEEP ENOUGH LIFT FOR FAIRLY WIDESPREAD CONVECTION. WIND FIELDS MAY BE STRONG ENOUGH FOR STORM ORGANIZATION WITH DAMAGING WIND AND/OR HAIL. MORE QUESTIONABLE WHETHER OR NOT INSTABILITY MANAGES TO DEVELOP HOWEVER. BOUNDARY PUSHES OFFSHORE THURSDAY NIGHT WHICH MAY ALLOW FOR A COOLER AND DRIER FRIDAY. TRAILING UPPER ENERGY ON SATURDAY BUT TOUGH CALL AS TO WHETHER OR NOT ENOUGH MOISTURE AROUND FOR MEANINGFUL RAIN CHANCES. DRY WNW FLOW FOR SUNDAY AND MONDAY. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...SHOWERS AND ISOLATED THUNDERSTORMS ARE MOVG E-NE ALONG AND NE OF A N MOVG BOUNDARY ALONG A KLBT/KILM LINE. THE BOUNDARY IS SHIFTING SLOWLY TO THE NORTH. VCTS COULD BE REPORTED AT KLBT EARLY THIS EVENING BUT FEEL ANY TS WILL BE N-NE OF THE TERMINAL. AN ISOLATED SHOWER COULD OCCUR AT KILM EARLY THIS EVENING BUT MOST SHOULD REMAIN N OF THE TERMINAL. CONVECTION SHOULD END LATER THIS EVENING. SHOWERS COULD AGAIN DEVELOP AND MOVE W-N OF KFLO/KLBT BY THE PRE-DAWN HOURS. MOS GUIDANCE FOR SUB VFR CONDITIONS OVERNIGHT IS NOT CONSISTENT... BUT GENERALLY SUGGEST IFR WILL BECOME POSSIBLE BY 04Z AT THE COASTAL /KLBT TERMINALS... AND A FEW HOURS LATER AT KFLO. CIGS WOULD LIFT TO MVFR AT THE COASTAL TERMINALS AFTER 07-08Z WITH IFR MORE LIKELY AT KFLO/KLBT THROUGH 12Z. CONFIDENCE OF TIMING IS LOW AS GUIDANCE SUGGEST CIGS WILL BE MORE TEMPO THAN PERSISTENT. FLIGHT CONDITIONS IMPROVING TO VFR BY MID-LATE MORNING. WILL INDICATE MORNING VCSH WITH VCTS DEVELOPING BY AFTERNOON. WINDS SHOULD BE S GUSTING TO AROUND 20 KTS. EXTENDED OUTLOOK...SCATTERED AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THURSDAY. OTHERWISE EXPECT VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 645 PM MONDAY...BASED ON OBSERVATIONS AND THE 18Z MODELS I HAVE INCREASED WIND SPEEDS THROUGH THE NIGHT BY A FEW KNOTS...WITH 10-15 KNOTS EXPECTED FOR MOST AREAS THROUGH THE NIGHT. THAT SHOULD SUPPORT 2 FOOT SEAS BUILDING THROUGH 3 FEET OVERNIGHT. A CLUSTER OF STRONG TO SEVERE THUNDERSTORMS ACROSS SOUTHEASTERN NC SHOULD LARGELY MISS THE COASTAL WATERS...BUT THERE IS A POTENTIAL FOR ISOLATED SHOWERS OR T-STORMS THIS EVENING...THEN PERHAPS REDEVELOPING VERY LATE TONIGHT. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... QUIET MARINE CONDITIONS OVERALL THROUGH THIS AFTERNOON. HIGH PRESSURE REMAINS OVER THE AREA WITH LINGERING BOUNDARY LIFTING NORTH OF THE THE WATERS. GRADIENT REMAINS LIGHT WITH SOUTH TO SOUTHEAST FLOW REMAINING UNDER 10 KT THROUGH THE MORNING HOURS WITH SEAS 2 FT OR LESS. MAY SEE A FEW LINGERING SHOWERS MAKE IT OVER THE WATERS JUST ALONG NORTHERN PORTION OF LOCAL WATERS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 PM MONDAY...EXPECT SOUTH- SOUTHWEST FLOW TO PERSIST THROUGH THE FORECAST PERIOD WITH INCREASING WINDS WEDNESDAY INTO WEDNESDAY EVENING WHERE WINDS WILL INCREASE TO AROUND 20 TO 25 KTS...WHILE THE REMAINDER OF THE PERIOD ANTICIPATE 15 TO 20 KTS WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE. AS FOR SEAS...2 TO 4 FT WITH 5 FT POSSIBLE. COULD SEE 6 TO 7 FT POSSIBLE IN THE OUTER WATERS WEDNESDAY INTO THURSDAY MORNING. ANTICIPATE CONDITIONS WILL WARRANT A SMALL CRAFT ADVISORY WEDNESDAY EVENING. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 PM MONDAY...PREFRONTAL FLOW REGIME ON THURSDAY PROBABLY STRONG ENOUGH TO WARRANT A SMALL CRAFT ADVISORY. A WINDSHIFT TO A MORE OFFSHORE DIRECTION THURSDAY NIGHT INTO FRIDAY PAIRED WITH A DOWNWARD TREND IN THE WIND SPEED WILL ALLOW ADVISORY TO BE DROPPED. OFFSHORE WINDS AND FAIRLY SEASONABLE SEAS CONTINUES INTO SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ107. MARINE...NONE. && $$ SYNOPSIS...SGL NEAR TERM...RGZ SHORT TERM...SGL LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
813 PM EDT MON APR 28 2014 .SYNOPSIS... UNSETTLED WEATHER WILL PERSIST OVER THE NEXT COUPLE OF DAYS. SHOWERS AND THUNDERSTORMS ARE EXPECTED INCREASE IN COVERAGE THROUGH WEDNESDAY AS A TROUGH OF LOW PRESSURE APPROACHES FROM THE WEST. ANOTHER QUICK ROUND OF RAIN IS POSSIBLE LATE FRIDAY AND SATURDAY BEFORE CONDITIONS DRY OUT INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 645 PM MONDAY...A CLUSTER OF STRONG TO SEVERE THUNDERSTORMS DEVELOPED ALONG A STATIONARY FRONT ACROSS SOUTHERN NORTH CAROLINA A FEW HOURS AGO. SUBJECTIVE SURFACE ANALYSIS SHOWED SIGNIFICANT BACKING OF THE LOW- LEVEL WIND ACROSS THE COASTAL PLAIN OF NC WHILE MODIFIED 18Z MODEL SOUNDINGS INDICATED CAPE AS HIGH AS 2700 J/KG EARLIER. MULTI CELL STORMS DEVELOPED BUT DID NOT DISPLAY SIGNIFICANT DEVIANT MOTION AS THEY MIGHT HAVE HAD SUPER CELLS DEVELOPED. STILL... HIGH REFLECTIVITY CORES REACHED INTO COLD ENOUGH LAYERS OF THE ATMOSPHERE TO LEAD US TO BELIEVE LARGE HAIL WAS A SIGNIFICANT THREAT. IF YOU OBSERVED HAIL OR WIND DAMAGE ACROSS ROBESON OR BLADEN COUNTIES THIS EVENING PLEASE LET US KNOW! THE FRONT SHOULD REMAIN NEARLY STATIONARY ACROSS SOUTHERN NORTH CAROLINA THIS EVENING...MAINLY JUST NORTH OF LUMBERTON AND ELIZABETHTOWN ARCING NORTHEASTWARD TOWARD NEW BERN ALONG THE COAST. THIS WILL LEAVE OUR FORECAST AREA IN A WARM AND HUMID TROPICAL AIRMASS WITH DEWPOINTS AND LOW TEMPERATURES FORECAST TO BE IN THE UPPER 60S. THE 500 MB RIDGE AXIS THAT HAS HELPED TO SUPPRESS PRECIPITATION OVER THE PAST FEW HOURS WILL FINALLY PUSH OFFSHORE LATE TONIGHT...AND THERE IS THE POTENTIAL FOR A REDEVELOPMENT OF AT LEAST ISOLATED SHOWERS/T-STORMS JUST BEFORE DAYBREAK AS WIND VECTORS BECOME DIFLUENT ALOFT AND THE 850 MB WIND BACKS AND STRENGTHENS. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... INCREASINGLY WARM AND MORE UNSTABLE AIR MASS WITH TEMPS INTO THE 80S MOST PLACES. MODELS STILL SHOW MID TO UPPER RIDGE LINED UP THE SOUTHEAST COAST WHICH SHOULD HELP TO INHIBIT SOME OF THE STRONGEST CONVECTION RUNNING SOUTH...BUT AS TEMPS WARMED INTO THE 80S AND DEWPOINTS INTO THE MID 60S CLOSER TO 70 OVER SOUTH CAROLINA. HRRR AND RUC SHOWING BEST CAPE LINED UP INLAND FROM SOUTH TO NORTH TOWARD DARLINGTON AND MARLBORO...BUT MAIN FOCUS OF STRONGER CONVECTION WILL BE ALONG THE LINGERING FRONTAL BOUNDARY JUST TO THE NORTH OF LOCAL FORECAST AREA. EXPECT SCT CONVECTION OVER THE AREA WITH MAIN FOCUS ALONG SEA BREEZE CONVERGENT BOUNDARY AND RUNNING ALONG LINGERING FRONTAL BOUNDARY. JUST NORTH OF BOUNDARY STILL SEEING TEMPS NOT EVEN REACHING 70 WITH COOLER AIR WEDGED IN. BEST HELICITY WILL RUN ALONG WARM FRONT WITH VALUES ABOVE 200 JUST TO NORTH. OVERALL SHOULD BE RATHER FINE BOUNDARY OF STRONGEST STORMS AS FORCING REMAINS WEAKER FARTHER SOUTH DUE TO INCREASED SUBSIDENCE WITH MID TO UPPER RIDGE OVER THE SOUTHEAST COAST. OVERALL THREAT OF HAIL AND STRONG WINDS WITH ANY STORMS THAT MAY REACH INTO OUR NORTHERN TIER COUNTIES. THE STEERING FLOW WILL PUSH ANY SHWRS/TSTMS THAT DEVELOP TOWARD THE COAST BUT THE MORE STABILIZED AIR BEHIND SEA BREEZE SHOULD KEEP THE IMMEDIATE COAST FREE OF STORMS. KEPT POPS VERY CLOSE TO PREVIOUS FORECAST WITH ONLY MINOR ADJUSTMENTS AND WILL UPDATE AS NEEDED ONCE CONVECTION FLARES. SHOULD SEE A FAIR AMOUNT OF CLOUDS AS CONVECTIVE DEBRIS CLOUDS WILL BE STEERED EAST MIXED WITH CU FIELD ACROSS THE AREA. THE STALLED BOUNDARY WILL BEGIN TO LIFT NORTH THROUGH TONIGHT AND EXPECT LOCALIZED CONVECTION TO SHUT DOWN AS HEATING OF THE DAY CUTS OFF AFTER SUNSET. THEREFORE WILL TAPER OFF POPS AFTER SUNSET LEAVING BEST CHC TO THE NORTH ALONG BOUNDARY. SHOULD BE A RELATIVELY QUIET NIGHT WITH LOWS WELL ABOVE CLIMO...RUNNING IN THE MID 60S IN A WARM AND HUMID AIRMASS. && .SHORT TERM /6 AM TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 PM MONDAY...ATTENTION THROUGHOUT THE ENTIRE FORECAST PERIOD WILL FOCUS ON UNSETTLED WEATHER...INCLUDING THE THREAT FOR SEVERE WEATHER JUST AHEAD OF AN APPROACHING COLD FRONT. LATEST GUIDANCE CONTINUES TO ILLUSTRATE A LONGWAVE TROUGH ACROSS THE CONUS WITH A PERSISTENT UPPER LEVEL LOW WHICH WILL SLOWLY PROGRESS ACROSS THE MIDWEST OVER THE NEXT COUPLE OF DAYS. WARM TEMPERATURES AND SOUTHWEST FLOW WILL ALLOW FOR A MOISTURE-RICH ATMOSPHERE...AS DEWPOINTS ARE WELL IN THE 60S...TO REMAIN IN PLACE WITH HIGHS ON TUESDAY IN THE LOWER 80S ACROSS THE ENTIRE FORECAST AREA. SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGHOUT THE DAY ON TUESDAY WHICH IS IN GOOD AGREEMENT AS OUR AREA IS INCLUDED IN SPC`S SLIGHT RISK. INTO WEDNESDAY...CONDITIONS WILL CONTINUE TO PROGRESS IN INCREASE...AS IT LOOKS THE BETTER INSTABILITY AND LIFT WILL MOVE INTO THE CENTRAL SC/NC/VA AREA...WITH A HEIGHTENED POSSIBILITY OF SEVERE ESPECIALLY IN OUR WESTERN ZONES. DIFFICULTY WILL BE TIMING AS MODELS HAVE EVER SO SLIGHTLY SLOWED DOWN THE PROGRESSION OF THE SYSTEM IN PAST RUNS. HOWEVER...OVERALL ANTICIPATE MAIN THREAT TO OCCUR WEDNESDAY THROUGHOUT THE DAY WITH AMPLE DIURNAL HEATING WITH HIGHS ON WEDNESDAY AGAIN IN THE 80S...INTO EARLY THURSDAY MORNING. WILL ALSO TAKE INTO ACCOUNT THE INTERACTION OF THE SEA BREEZE AS WELL ON BOTH DAYS AND ANY OTHER WANDERING BOUNDARIES ABOUT THE AREA. THE PRIMARY THREATS WILL BE HAIL AND DAMAGING WINDS...ALONG WITH THE POSSIBILITY OF TORNADOES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...THURSDAY MAY BE RATHER ACTIVE. THE UPPER RIDGE AXIS WILL BE OFFSHORE ALLOWING FOR DEEP SWRLY FLOW. SURFACE BOUNDARY AND UPPER LEVEL VORT MAXES MAY SPONSOR DEEP ENOUGH LIFT FOR FAIRLY WIDESPREAD CONVECTION. WIND FIELDS MAY BE STRONG ENOUGH FOR STORM ORGANIZATION WITH DAMAGING WIND AND/OR HAIL. MORE QUESTIONABLE WHETHER OR NOT INSTABILITY MANAGES TO DEVELOP HOWEVER. BOUNDARY PUSHES OFFSHORE THURSDAY NIGHT WHICH MAY ALLOW FOR A COOLER AND DRIER FRIDAY. TRAILING UPPER ENERGY ON SATURDAY BUT TOUGH CALL AS TO WHETHER OR NOT ENOUGH MOISTURE AROUND FOR MEANINGFUL RAIN CHANCES. DRY WNW FLOW FOR SUNDAY AND MONDAY. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...SHOWERS AND ISOLATED THUNDERSTORMS ARE MOVG E-NE ALONG AND NE OF A N MOVG BOUNDARY ALONG A KLBT/KILM LINE. THE BOUNDARY IS SHIFTING SLOWLY TO THE NORTH. VCTS COULD BE REPORTED AT KLBT EARLY THIS EVENING BUT FEEL ANY TS WILL BE N-NE OF THE TERMINAL. AN ISOLATED SHOWER COULD OCCUR AT KILM EARLY THIS EVENING BUT MOST SHOULD REMAIN N OF THE TERMINAL. CONVECTION SHOULD END LATER THIS EVENING. SHOWERS COULD AGAIN DEVELOP AND MOVE W-N OF KFLO/KLBT BY THE PRE-DAWN HOURS. MOS GUIDANCE FOR SUB VFR CONDITIONS OVERNIGHT IS NOT CONSISTENT... BUT GENERALLY SUGGEST IFR WILL BECOME POSSIBLE BY 04Z AT THE COASTAL /KLBT TERMINALS... AND A FEW HOURS LATER AT KFLO. CIGS WOULD LIFT TO MVFR AT THE COASTAL TERMINALS AFTER 07-08Z WITH IFR MORE LIKELY AT KFLO/KLBT THROUGH 12Z. CONFIDENCE OF TIMING IS IS LOW AS GUIDANCE SUGGEST CIGS WILL BE MORE TEMPO THAN PERSISTENT. FLIGHT CONDITIONS IMPROVING TO VFR BY MID-LATE MORNING. WILL INDICATE MORNING VCSH WITH VCTS DEVELOPING BY AFTERNOON. WINDS SHOULD BE S GUSTING TO AROUND 20 KTS. EXTENDED OUTLOOK...SCATTERED AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THURSDAY. OTHERWISE EXPECT VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 645 PM MONDAY...BASED ON OBSERVATIONS AND THE 18Z MODELS I HAVE INCREASED WIND SPEEDS THROUGH THE NIGHT BY A FEW KNOTS...WITH 10-15 KNOTS EXPECTED FOR MOST AREAS THROUGH THE NIGHT. THAT SHOULD SUPPORT 2 FOOT SEAS BUILDING THROUGH 3 FEET OVERNIGHT. A CLUSTER OF STRONG TO SEVERE THUNDERSTORMS ACROSS SOUTHEASTERN NC SHOULD LARGELY MISS THE COASTAL WATERS...BUT THERE IS A POTENTIAL FOR ISOLATED SHOWERS OR T-STORMS THIS EVENING...THEN PERHAPS REDEVELOPING VERY LATE TONIGHT. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... QUIET MARINE CONDITIONS OVERALL THROUGH THIS AFTERNOON. HIGH PRESSURE REMAINS OVER THE AREA WITH LINGERING BOUNDARY LIFTING NORTH OF THE THE WATERS. GRADIENT REMAINS LIGHT WITH SOUTH TO SOUTHEAST FLOW REMAINING UNDER 10 KT THROUGH THE MORNING HOURS WITH SEAS 2 FT OR LESS. MAY SEE A FEW LINGERING SHOWERS MAKE IT OVER THE WATERS JUST ALONG NORTHERN PORTION OF LOCAL WATERS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 PM MONDAY...EXPECT SOUTH- SOUTHWEST FLOW TO PERSIST THROUGH THE FORECAST PERIOD WITH INCREASING WINDS WEDNESDAY INTO WEDNESDAY EVENING WHERE WINDS WILL INCREASE TO AROUND 20 TO 25 KTS...WHILE THE REMAINDER OF THE PERIOD ANTICIPATE 15 TO 20 KTS WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE. AS FOR SEAS...2 TO 4 FT WITH 5 FT POSSIBLE. COULD SEE 6 TO 7 FT POSSIBLE IN THE OUTER WATERS WEDNESDAY INTO THURSDAY MORNING. ANTICIPATE CONDITIONS WILL WARRANT A SMALL CRAFT ADVISORY WEDNESDAY EVENING. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 PM MONDAY...PREFRONTAL FLOW REGIME ON THURSDAY PROBABLY STRONG ENOUGH TO WARRANT A SMALL CRAFT ADVISORY. A WINDSHIFT TO A MORE OFFSHORE DIRECTION THURSDAY NIGHT INTO FRIDAY PAIRED WITH A DOWNWARD TREND IN THE WIND SPEED WILL ALLOW ADVISORY TO BE DROPPED. OFFSHORE WINDS AND FAIRLY SEASONABLE SEAS CONTINUES INTO SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ107. MARINE...NONE. && $$ SYNOPSIS...SGL NEAR TERM...RGZ SHORT TERM...SGL LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
131 PM CDT SUN APR 27 2014 .UPDATE... ISSUED AT 123 PM CDT SUN APR 27 2014 SOME ELEVATED CONVECTION BEGINNING AGAIN THIS AFTERNOON VICINITY OF DICKINSON. WILL ADD SOME SCATTERED THUNDERSTORMS THIS AFTERNOON SOUTHWEST. OTHERWISE...PRECIPITATION CONTINUES TO ROTATE NORTH AND EAST THIS AFTERNOON. TEMPERATURES HAVE COOLED TO THE WET BULB TEMPERATURES ACROSS THE NORTH..WHICH IS IN THE LOWER TO MIDDLE 30S. EXPECTING TEMPERATURES TO STAY STEADY THIS AFTERNOON SO CUT HIGH TEMPERATURES INTO THE 30S NORTH THIS AFTERNOON. UPDATE ISSUED AT 945 AM CDT SUN APR 27 2014 FIRST SURGE OF PRECIPITATION HAS MOVED THROUGH THE SOUTH AND IS NOW PIVOTING NORTH AND WEST ACROSS THE REGION. WILL FOCUS THE HIGHER POPS WEST AND NORTH WITH LOWEST SOUTH CENTRAL AND SOUTHEAST TODAY. EARLY STAGES OF THIS CUT OFF LOW ARE RAPIDLY EVOLVING WITH A SECOND SURGE OF MOISTURE ALREADY SHOWING UP ON THE WATER VAPOR IMAGERY MOVING INTO SOUTH DAKOTA. THIS WILL BRING ANOTHER ROUND OF RAIN TO THE SOUTH CENTRAL LATE THIS AFTERNOON AND TONIGHT. SO FAR WIND ADVISORY LOOKS REASONABLE WITH THE HIGHER WINDS EAST. REMOVED THE MENTION OF THUNDERSTORMS AS MORNING SOUNDINGS SHOW ONLY ELEVATED INSTABILITY ABOVE 700 MB AT ABR AND THAT EVEN LOOKS LIMITED. UPDATE ISSUED AT 645 AM CDT SUN APR 27 2014 A BAND OF SHOWERS WITH EMBEDDED THUNDER CONTINUES TO LIFT NORTH ACROSS SOUTHERN NORTH DAKOTA THIS MORNING. CURRENT FORECAST HAS A GOOD HANDLE ON THE TRACK OF THIS PRECIPITATION OVER THE NEXT FEW HOURS SO NO UPDATES PLANNED. STILL SOME UNCERTAINTY ON HOW THINGS WILL PLAY OUT THIS AFTERNOON AFTER THIS BAND LIFTS NORTH. COULD BE A BREAK THIS AFTERNOON AND EARLY EVENING FOR CENTRAL PORTIONS OF THE STATE AS PRECIPITATION BECOMES FOCUSED MORE IN THE WEST AND EASTERN MONTANA. BUT ANOTHER WAVE MOVES THROUGH TONIGHT BRINGING WIDESPREAD PRECIPITATION ONCE AGAIN. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 THUNDER...HEAVY RAINFALL AND SNOWFALL POTENTIAL WILL HIGHLIGHT THE SHORT TERM. FOR THIS MORNING AS OF 08 UTC...THUNDERSTORM ACTIVITY HAS STEADILY INCREASED ACROSS SOUTH DAKOTA IN STRONG MOISTURE TRANSPORT AND ISENTROPIC LIFT WITHIN A ZONE OF 700 MB BASED CAPE VALUES OF 700-1000 J/KG. FOLLOWING THE 06 UTC RAP/HRRR SOLUTIONS...THIS ZONE OF ELEVATED INSTABILITY AND ASSOCIATED CONVECTION WILL CONTINUE TO PROPAGATE NORTH INTO THE I-94 CORRIDOR BY 11 UTC. THE TREND HAS BEEN FOR THE THUNDERSTORMS ACROSS SOUTH DAKOTA TO REMAIN SUB- SEVERE. THAT SAID...PEA SIZE HAIL IS POSSIBLE WITH THE STRONGER STORMS. DID EXPAND THE MENTION OF THUNDERSTORMS TO MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE DAY GENERALLY EAST OF HIGHWAY 85 WHERE THE RAP CONTINUES TO DEPICT 300-500 J/KG OF 700 MB CAPE. IN GENERAL...THE 00 UTC DETERMINISTIC SUITE AND 03 UTC SREF ARE IN GOOD AGREEMENT ON THE EVOLUTION OF THE DEEP LOW ACROSS NEBRASKA THIS MORNING...SLOWLY PROPAGATING INTO MISSOURI ON TUESDAY. THE HEAVIEST RAINFALL AXIS FOR NORTH DAKOTA REMAINS ACROSS SOUTHWEST NORTH DAKOTA IN THE VICINITY OF THE INVERTED SURFACE TROUGH...WHERE TWO TO POSSIBLY THREE INCHES ARE POSSIBLE TROUGH TUESDAY. SEE THE HYDROLOGY SECTION BELOW FOR POTENTIAL IMPACTS. ELSEWHERE...WIDESPREAD ONE TO TWO INCH AMOUNTS ARE EXPECTED. FINALLY...IN REGARDS TO SNOWFALL...DYNAMIC COOLING THIS EVENING AND TONIGHT ACROSS THE WEST AND NORTH CENTRAL WILL BE SUFFICIENT ENOUGH FOR A POTENTIAL CHANGE OVER TO SNOW LATE TONIGHT INTO MONDAY MORNING. SNOWFALL MAY BECOME MORE WIDESPREAD MONDAY NIGHT INTO TUESDAY ACROSS A GREATER PORTION OF WESTERN AND CENTRAL NORTH DAKOTA WITH INCREASED LOW TO MID LEVEL COLD AIR ADVECTION. GIVEN THE WARM GROUND AND NEAR FREEZING TEMPERATURES...SNOW RATIOS WILL BE LOW. THAT SAID...ONE TO TWO INCHES MAY BE POSSIBLE ACROSS THE NORTHWEST TONIGHT INTO MONDAY MORNING. SIMILAR ACCUMULATIONS MAY BE POSSIBLE FOR THE NORTH CENTRAL AND AGAIN ACROSS THE NORTHWEST MONDAY NIGHT INTO TUESDAY MORNING...WITH A DUSTING ELSEWHERE. WILL HIGHLIGHT WITH AN SPS FOR NOW. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 BY THE TIME WE REACH THE LONG TERM PERIOD...OUR PESKY UPPER LOW IS STILL SPINNING OVER THE MIDWEST...LIFTING INTO THE WESTERN GREAT LAKES REGION. INITIALLY DRIER AIR WRAPS AROUND THE LOW BRINGING AND END TO PRECIPITATION FROM NORTH TO SOUTH. ANY LINGERING PRECIPITATION TUESDAY EVENING WOULD LIKELY BE A RAIN SNOW MIX OR ALL SNOW AS COLDER AIR IS WELL ESTABLISHED OVER THE AREA. HOWEVER PRECIPITATION CHANCES WILL BE WANING AND LITTLE TO NO ACCUMULATIONS ARE EXPECTED. ON WEDNESDAY...ANOTHER WAVE OF WRAP AROUND MOISTURE SPREADS EAST TO WEST ACROSS THE AREA BRINGING A CHANCE OF RAIN OR SNOW SHOWERS. WITH THE BEST CHANCES OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. THEN WE DRY OUT AGAIN FROM NORTH TO SOUTH WEDNESDAY NIGHT INTO THURSDAY. ONCE AGAIN LITTLE OR NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED WEDNESDAY THROUGH WEDNESDAY NIGHT BEYOND THIS PERIOD MODELS ARE COMING INTO BETTER AGREEMENT ON A NORTHWEST FLOW PATTERN...WITH A SHARP RIDGE DEVELOPING OVER THE WESTERN U.S. BUT TIMING AND PLACEMENT ISSUES STILL REMAIN. WE WILL SEE PERIODIC QUICK MOVING CLIPPER TYPE SYSTEMS TRACK SOUTHEAST THROUGH THE LOCAL AREA LATE IN THE WORK WEEK AND INTO NEXT WEEKEND...WITH NO BIG WARM-UPS IN STORE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 123 PM CDT SUN APR 27 2014 SLOW MOVING LARGE LOW PRESSURE ACROSS THE CENTRAL PLAINS WILL MAINTAIN IFR CONDITIONS ACROSS THE REGION THIS AFTERNOON AND TONIGHT. SOUTHEAST UPSLOPE FLOW SHOULD LOWER CEILINGS TO LOW IFR AT KDIK. A MIX OF RAIN AND SNOW FROM KDIK-KISN-KMOT WILL LIMIT VSBYS TO BELOW 1 MILE AFTER 10Z. && .HYDROLOGY... ISSUED AT 316 AM CDT SUN APR 27 2014 WIDESPREAD BETWEEN ONE AND TWO INCHES OF RAIN IS FORECAST ACROSS THE AREA WITH UP TO THREE INCHES IN SOUTHWEST NORTH DAKOTA. THIS COULD HAVE SIGNIFICANT IMPACTS IN BASIN HYDROLOGIC RESPONSE. LIMITING FACTORS IN RIVER RESPONSE WILL BE THAT THE FROST IS OUT OF THE GROUND...AND IT HAS BEEN DRY. SOILS WILL BE ABLE TO ABSORB A LOT OF THE RAIN...BUT NOT ALL OF IT. THAT SAID...STREAM AND RIVER RISES...POSSIBLY ABOVE MINOR FLOOD STAGE...ARE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005-013-023-025- 036-037-047-048-050-051. && $$ UPDATE...WAA SHORT TERM...AYD LONG TERM...TWH AVIATION...WAA HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1003 AM CDT SUN APR 27 2014 .UPDATE... ISSUED AT 945 AM CDT SUN APR 27 2014 FIRST SURGE OF PRECIPITATION HAS MOVED THROUGH THE SOUTH AND IS NOW PIVOTING NORTH AND WEST ACROSS THE REGION. WILL FOCUS THE HIGHER POPS WEST AND NORTH WITH LOWEST SOUTH CENTRAL AND SOUTHEAST TODAY. EARLY STAGES OF THIS CUT OFF LOW ARE RAPIDLY EVOLVING WITH A SECOND SURGE OF MOISTURE ALREADY SHOWING UP ON THE WATER VAPOR IMAGERY MOVING INTO SOUTH DAKOTA. THIS WILL BRING ANOTHER ROUND OF RAIN TO THE SOUTH CENTRAL LATE THIS AFTERNOON AND TONIGHT. SO FAR WIND ADVISORY LOOKS REASONABLE WITH THE HIGHER WINDS EAST. REMOVED THE MENTION OF THUNDERSTORMS AS MORNING SOUNDINGS SHOW ONLY ELEVATED INSTABILITY ABOVE 700 MB AT ABR AND THAT EVEN LOOKS LIMITED. UPDATE ISSUED AT 645 AM CDT SUN APR 27 2014 A BAND OF SHOWERS WITH EMBEDDED THUNDER CONTINUES TO LIFT NORTH ACROSS SOUTHERN NORTH DAKOTA THIS MORNING. CURRENT FORECAST HAS A GOOD HANDLE ON THE TRACK OF THIS PRECIPITATION OVER THE NEXT FEW HOURS SO NO UPDATES PLANNED. STILL SOME UNCERTAINTY ON HOW THINGS WILL PLAY OUT THIS AFTERNOON AFTER THIS BAND LIFTS NORTH. COULD BE A BREAK THIS AFTERNOON AND EARLY EVENING FOR CENTRAL PORTIONS OF THE STATE AS PRECIPITATION BECOMES FOCUSED MORE IN THE WEST AND EASTERN MONTANA. BUT ANOTHER WAVE MOVES THROUGH TONIGHT BRINGING WIDESPREAD PRECIPITATION ONCE AGAIN. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 THUNDER...HEAVY RAINFALL AND SNOWFALL POTENTIAL WILL HIGHLIGHT THE SHORT TERM. FOR THIS MORNING AS OF 08 UTC...THUNDERSTORM ACTIVITY HAS STEADILY INCREASED ACROSS SOUTH DAKOTA IN STRONG MOISTURE TRANSPORT AND ISENTROPIC LIFT WITHIN A ZONE OF 700 MB BASED CAPE VALUES OF 700-1000 J/KG. FOLLOWING THE 06 UTC RAP/HRRR SOLUTIONS...THIS ZONE OF ELEVATED INSTABILITY AND ASSOCIATED CONVECTION WILL CONTINUE TO PROPAGATE NORTH INTO THE I-94 CORRIDOR BY 11 UTC. THE TREND HAS BEEN FOR THE THUNDERSTORMS ACROSS SOUTH DAKOTA TO REMAIN SUB- SEVERE. THAT SAID...PEA SIZE HAIL IS POSSIBLE WITH THE STRONGER STORMS. DID EXPAND THE MENTION OF THUNDERSTORMS TO MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE DAY GENERALLY EAST OF HIGHWAY 85 WHERE THE RAP CONTINUES TO DEPICT 300-500 J/KG OF 700 MB CAPE. IN GENERAL...THE 00 UTC DETERMINISTIC SUITE AND 03 UTC SREF ARE IN GOOD AGREEMENT ON THE EVOLUTION OF THE DEEP LOW ACROSS NEBRASKA THIS MORNING...SLOWLY PROPAGATING INTO MISSOURI ON TUESDAY. THE HEAVIEST RAINFALL AXIS FOR NORTH DAKOTA REMAINS ACROSS SOUTHWEST NORTH DAKOTA IN THE VICINITY OF THE INVERTED SURFACE TROUGH...WHERE TWO TO POSSIBLY THREE INCHES ARE POSSIBLE TROUGH TUESDAY. SEE THE HYDROLOGY SECTION BELOW FOR POTENTIAL IMPACTS. ELSEWHERE...WIDESPREAD ONE TO TWO INCH AMOUNTS ARE EXPECTED. FINALLY...IN REGARDS TO SNOWFALL...DYNAMIC COOLING THIS EVENING AND TONIGHT ACROSS THE WEST AND NORTH CENTRAL WILL BE SUFFICIENT ENOUGH FOR A POTENTIAL CHANGE OVER TO SNOW LATE TONIGHT INTO MONDAY MORNING. SNOWFALL MAY BECOME MORE WIDESPREAD MONDAY NIGHT INTO TUESDAY ACROSS A GREATER PORTION OF WESTERN AND CENTRAL NORTH DAKOTA WITH INCREASED LOW TO MID LEVEL COLD AIR ADVECTION. GIVEN THE WARM GROUND AND NEAR FREEZING TEMPERATURES...SNOW RATIOS WILL BE LOW. THAT SAID...ONE TO TWO INCHES MAY BE POSSIBLE ACROSS THE NORTHWEST TONIGHT INTO MONDAY MORNING. SIMILAR ACCUMULATIONS MAY BE POSSIBLE FOR THE NORTH CENTRAL AND AGAIN ACROSS THE NORTHWEST MONDAY NIGHT INTO TUESDAY MORNING...WITH A DUSTING ELSEWHERE. WILL HIGHLIGHT WITH AN SPS FOR NOW. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 BY THE TIME WE REACH THE LONG TERM PERIOD...OUR PESKY UPPER LOW IS STILL SPINNING OVER THE MIDWEST...LIFTING INTO THE WESTERN GREAT LAKES REGION. INITIALLY DRIER AIR WRAPS AROUND THE LOW BRINGING AND END TO PRECIPITATION FROM NORTH TO SOUTH. ANY LINGERING PRECIPITATION TUESDAY EVENING WOULD LIKELY BE A RAIN SNOW MIX OR ALL SNOW AS COLDER AIR IS WELL ESTABLISHED OVER THE AREA. HOWEVER PRECIPITATION CHANCES WILL BE WANING AND LITTLE TO NO ACCUMULATIONS ARE EXPECTED. ON WEDNESDAY...ANOTHER WAVE OF WRAP AROUND MOISTURE SPREADS EAST TO WEST ACROSS THE AREA BRINGING A CHANCE OF RAIN OR SNOW SHOWERS. WITH THE BEST CHANCES OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. THEN WE DRY OUT AGAIN FROM NORTH TO SOUTH WEDNESDAY NIGHT INTO THURSDAY. ONCE AGAIN LITTLE OR NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED WEDNESDAY THROUGH WEDNESDAY NIGHT BEYOND THIS PERIOD MODELS ARE COMING INTO BETTER AGREEMENT ON A NORTHWEST FLOW PATTERN...WITH A SHARP RIDGE DEVELOPING OVER THE WESTERN U.S. BUT TIMING AND PLACEMENT ISSUES STILL REMAIN. WE WILL SEE PERIODIC QUICK MOVING CLIPPER TYPE SYSTEMS TRACK SOUTHEAST THROUGH THE LOCAL AREA LATE IN THE WORK WEEK AND INTO NEXT WEEKEND...WITH NO BIG WARM-UPS IN STORE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT945 AM CDT SUN APR 27 2014 LARGE AND SLOW MOVING LOW PRESSURE ACROSS THE CENTRAL PLAINS WILL BRING WIDESPREAD IFR CONDITIONS ACROSS WEST AND CENTRAL NORTH DAKOTA TODAY AND TONIGHT. GUSTY EAST WINDS 25 TO 38KTS WILL IMPACT KJMS THROUGH 00Z. && .HYDROLOGY... ISSUED AT 316 AM CDT SUN APR 27 2014 WIDESPREAD BETWEEN ONE AND TWO INCHES OF RAIN IS FORECAST ACROSS THE AREA WITH UP TO THREE INCHES IN SOUTHWEST NORTH DAKOTA. THIS COULD HAVE SIGNIFICANT IMPACTS IN BASIN HYDROLOGIC RESPONSE. LIMITING FACTORS IN RIVER RESPONSE WILL BE THAT THE FROST IS OUT OF THE GROUND...AND IT HAS BEEN DRY. SOILS WILL BE ABLE TO ABSORB A LOT OF THE RAIN...BUT NOT ALL OF IT. THAT SAID...STREAM AND RIVER RISES...POSSIBLY ABOVE MINOR FLOOD STAGE...ARE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005-013-023-025- 036-037-047-048-050-051. && $$ UPDATE...WAA SHORT TERM...AYD LONG TERM...TWH AVIATION...WAA HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
646 AM CDT SUN APR 27 2014 .UPDATE... ISSUED AT 645 AM CDT SUN APR 27 2014 A BAND OF SHOWERS WITH EMBEDDED THUNDER CONTINUES TO LIFT NORTH ACROSS SOUTHERN NORTH DAKOTA THIS MORNING. CURRENT FORECAST HAS A GOOD HANDLE ON THE TRACK OF THIS PRECIPITATION OVER THE NEXT FEW HOURS SO NO UPDATES PLANNED. STILL SOME UNCERTAINTY ON HOW THINGS WILL PLAY OUT THIS AFTERNOON AFTER THIS BAND LIFTS NORTH. COULD BE A BREAK THIS AFTERNOON AND EARLY EVENING FOR CENTRAL PORTIONS OF THE STATE AS PRECIPITATION BECOMES FOCUSED MORE IN THE WEST AND EASTERN MONTANA. BUT ANOTHER WAVE MOVES THROUGH TONIGHT BRINGING WIDESPREAD PRECIPITATION ONCE AGAIN. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 THUNDER...HEAVY RAINFALL AND SNOWFALL POTENTIAL WILL HIGHLIGHT THE SHORT TERM. FOR THIS MORNING AS OF 08 UTC...THUNDERSTORM ACTIVITY HAS STEADILY INCREASED ACROSS SOUTH DAKOTA IN STRONG MOISTURE TRANSPORT AND ISENTROPIC LIFT WITHIN A ZONE OF 700 MB BASED CAPE VALUES OF 700-1000 J/KG. FOLLOWING THE 06 UTC RAP/HRRR SOLUTIONS...THIS ZONE OF ELEVATED INSTABILITY AND ASSOCIATED CONVECTION WILL CONTINUE TO PROPAGATE NORTH INTO THE I-94 CORRIDOR BY 11 UTC. THE TREND HAS BEEN FOR THE THUNDERSTORMS ACROSS SOUTH DAKOTA TO REMAIN SUB- SEVERE. THAT SAID...PEA SIZE HAIL IS POSSIBLE WITH THE STRONGER STORMS. DID EXPAND THE MENTION OF THUNDERSTORMS TO MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE DAY GENERALLY EAST OF HIGHWAY 85 WHERE THE RAP CONTINUES TO DEPICT 300-500 J/KG OF 700 MB CAPE. IN GENERAL...THE 00 UTC DETERMINISTIC SUITE AND 03 UTC SREF ARE IN GOOD AGREEMENT ON THE EVOLUTION OF THE DEEP LOW ACROSS NEBRASKA THIS MORNING...SLOWLY PROPAGATING INTO MISSOURI ON TUESDAY. THE HEAVIEST RAINFALL AXIS FOR NORTH DAKOTA REMAINS ACROSS SOUTHWEST NORTH DAKOTA IN THE VICINITY OF THE INVERTED SURFACE TROUGH...WHERE TWO TO POSSIBLY THREE INCHES ARE POSSIBLE TROUGH TUESDAY. SEE THE HYDROLOGY SECTION BELOW FOR POTENTIAL IMPACTS. ELSEWHERE...WIDESPREAD ONE TO TWO INCH AMOUNTS ARE EXPECTED. FINALLY...IN REGARDS TO SNOWFALL...DYNAMIC COOLING THIS EVENING AND TONIGHT ACROSS THE WEST AND NORTH CENTRAL WILL BE SUFFICIENT ENOUGH FOR A POTENTIAL CHANGE OVER TO SNOW LATE TONIGHT INTO MONDAY MORNING. SNOWFALL MAY BECOME MORE WIDESPREAD MONDAY NIGHT INTO TUESDAY ACROSS A GREATER PORTION OF WESTERN AND CENTRAL NORTH DAKOTA WITH INCREASED LOW TO MID LEVEL COLD AIR ADVECTION. GIVEN THE WARM GROUND AND NEAR FREEZING TEMPERATURES...SNOW RATIOS WILL BE LOW. THAT SAID...ONE TO TWO INCHES MAY BE POSSIBLE ACROSS THE NORTHWEST TONIGHT INTO MONDAY MORNING. SIMILAR ACCUMULATIONS MAY BE POSSIBLE FOR THE NORTH CENTRAL AND AGAIN ACROSS THE NORTHWEST MONDAY NIGHT INTO TUESDAY MORNING...WITH A DUSTING ELSEWHERE. WILL HIGHLIGHT WITH AN SPS FOR NOW. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 BY THE TIME WE REACH THE LONG TERM PERIOD...OUR PESKY UPPER LOW IS STILL SPINNING OVER THE MIDWEST...LIFTING INTO THE WESTERN GREAT LAKES REGION. INITIALLY DRIER AIR WRAPS AROUND THE LOW BRINGING AND END TO PRECIPITATION FROM NORTH TO SOUTH. ANY LINGERING PRECIPITATION TUESDAY EVENING WOULD LIKELY BE A RAIN SNOW MIX OR ALL SNOW AS COLDER AIR IS WELL ESTABLISHED OVER THE AREA. HOWEVER PRECIPITATION CHANCES WILL BE WANING AND LITTLE TO NO ACCUMULATIONS ARE EXPECTED. ON WEDNESDAY...ANOTHER WAVE OF WRAP AROUND MOISTURE SPREADS EAST TO WEST ACROSS THE AREA BRINGING A CHANCE OF RAIN OR SNOW SHOWERS. WITH THE BEST CHANCES OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. THEN WE DRY OUT AGAIN FROM NORTH TO SOUTH WEDNESDAY NIGHT INTO THURSDAY. ONCE AGAIN LITTLE OR NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED WEDNESDAY THROUGH WEDNESDAY NIGHT BEYOND THIS PERIOD MODELS ARE COMING INTO BETTER AGREEMENT ON A NORTHWEST FLOW PATTERN...WITH A SHARP RIDGE DEVELOPING OVER THE WESTERN U.S. BUT TIMING AND PLACEMENT ISSUES STILL REMAIN. WE WILL SEE PERIODIC QUICK MOVING CLIPPER TYPE SYSTEMS TRACK SOUTHEAST THROUGH THE LOCAL AREA LATE IN THE WORK WEEK AND INTO NEXT WEEKEND...WITH NO BIG WARM-UPS IN STORE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 645 AM CDT SUN APR 27 2014 WIDESPREAD MVFR CONDITIONS IN STRATUS...RAIN SHOWERS AND EMBEDDED THUNDERSTORMS ARE FORECAST ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. CONDITIONS WILL TREND TOWARDS IFR AND BELOW FOR MOST LOCATIONS TONIGHT...WITH RAIN POSSIBLY CHANGING TO SNOW AT KISN/KDIK/KMOT. STRONG EASTERLY WINDS WILL CONTINUE THIS MORNING AND AFTERNOON. && .HYDROLOGY... ISSUED AT 316 AM CDT SUN APR 27 2014 WIDESPREAD BETWEEN ONE AND TWO INCHES OF RAIN IS FORECAST ACROSS THE AREA WITH UP TO THREE INCHES IN SOUTHWEST NORTH DAKOTA. THIS COULD HAVE SIGNIFICANT IMPACTS IN BASIN HYDROLOGIC RESPONSE. LIMITING FACTORS IN RIVER RESPONSE WILL BE THAT THE FROST IS OUT OF THE GROUND...AND IT HAS BEEN DRY. SOILS WILL BE ABLE TO ABSORB A LOT OF THE RAIN...BUT NOT ALL OF IT. THAT SAID...STREAM AND RIVER RISES...POSSIBLY ABOVE MINOR FLOOD STAGE...ARE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005-013-023-025- 036-037-047-048-050-051. && $$ UPDATE...TWH SHORT TERM...AYD LONG TERM...TWH AVIATION...AYD HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
318 AM CDT SUN APR 27 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 THUNDER...HEAVY RAINFALL AND SNOWFALL POTENTIAL WILL HIGHLIGHT THE SHORT TERM. FOR THIS MORNING AS OF 08 UTC...THUNDERSTORM ACTIVITY HAS STEADILY INCREASED ACROSS SOUTH DAKOTA IN STRONG MOISTURE TRANSPORT AND ISENTROPIC LIFT WITHIN A ZONE OF 700 MB BASED CAPE VALUES OF 700-1000 J/KG. FOLLOWING THE 06 UTC RAP/HRRR SOLUTIONS...THIS ZONE OF ELEVATED INSTABILITY AND ASSOCIATED CONVECTION WILL CONTINUE TO PROPAGATE NORTH INTO THE I-94 CORRIDOR BY 11 UTC. THE TREND HAS BEEN FOR THE THUNDERSTORMS ACROSS SOUTH DAKOTA TO REMAIN SUB- SEVERE. THAT SAID...PEA SIZE HAIL IS POSSIBLE WITH THE STRONGER STORMS. DID EXPAND THE MENTION OF THUNDERSTORMS TO MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE DAY GENERALLY EAST OF HIGHWAY 85 WHERE THE RAP CONTINUES TO DEPICT 300-500 J/KG OF 700 MB CAPE. IN GENERAL...THE 00 UTC DETERMINISTIC SUITE AND 03 UTC SREF ARE IN GOOD AGREEMENT ON THE EVOLUTION OF THE DEEP LOW ACROSS NEBRASKA THIS MORNING...SLOWLY PROPAGATING INTO MISSOURI ON TUESDAY. THE HEAVIEST RAINFALL AXIS FOR NORTH DAKOTA REMAINS ACROSS SOUTHWEST NORTH DAKOTA IN THE VICINITY OF THE INVERTED SURFACE TROUGH...WHERE TWO TO POSSIBLY THREE INCHES ARE POSSIBLE TROUGH TUESDAY. SEE THE HYDROLOGY SECTION BELOW FOR POTENTIAL IMPACTS. ELSEWHERE...WIDESPREAD ONE TO TWO INCH AMOUNTS ARE EXPECTED. FINALLY...IN REGARDS TO SNOWFALL...DYNAMIC COOLING THIS EVENING AND TONIGHT ACROSS THE WEST AND NORTH CENTRAL WILL BE SUFFICIENT ENOUGH FOR A POTENTIAL CHANGE OVER TO SNOW LATE TONIGHT INTO MONDAY MORNING. SNOWFALL MAY BECOME MORE WIDESPREAD MONDAY NIGHT INTO TUESDAY ACROSS A GREATER PORTION OF WESTERN AND CENTRAL NORTH DAKOTA WITH INCREASED LOW TO MID LEVEL COLD AIR ADVECTION. GIVEN THE WARM GROUND AND NEAR FREEZING TEMPERATURES...SNOW RATIOS WILL BE LOW. THAT SAID...ONE TO TWO INCHES MAY BE POSSIBLE ACROSS THE NORTHWEST TONIGHT INTO MONDAY MORNING. SIMILIAR ACCUMULATIONS MAY BE POSSIBLE FOR THE NORTH CENTRAL AND AGAIN ACROSS THE NORTHWEST MONDAY NIGHT INTO TUESDAY MORNING...WITH A DUSTING ELSEWHERE. WILL HIGHLIGHT WITH AN SPS FOR NOW. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 316 AM CDT SUN APR 27 2014 BY THE TIME WE REACH THE LONG TERM PERIOD...OUR PESKY UPPER LOW IS STILL SPINNING OVER THE MIDWEST...LIFTING INTO THE WESTERN GREAT LAKES REGION. INITIALLY DRIER AIR WRAPS AROUND THE LOW BRINGING AND END TO PRECIPITATION FROM NORTH TO SOUTH. ANY LINGERING PRECIPITATION TUESDAY EVENING WOULD LIKELY BE A RAIN SNOW MIX OR ALL SNOW AS COLDER AIR IS WELL ESTABLISHED OVER THE AREA. HOWEVER PRECIPITATION CHANCES WILL BE WANING AND LITTLE TO NO ACCUMULATIONS ARE EXPECTED. ON WEDNESDAY...ANOTHER WAVE OF WRAP AROUND MOISTURE SPREADS EAST TO WEST ACROSS THE AREA BRINGING A CHANCE OF RAIN OR SNOW SHOWERS. WITH THE BEST CHANCES OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. THEN WE DRY OUT AGAIN FROM NORTH TO SOUTH WEDNESDAY NIGHT INTO THURSDAY. ONCE AGAIN LITTLE OR NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED WEDNESDAY THROUGH WEDNESDAY NIGHT BEYOND THIS PERIOD MODELS ARE COMING INTO BETTER AGREEMENT ON A NORTHWEST FLOW PATTERN...WITH A SHARP RIDGE DEVELOPING OVER THE WESTERN U.S. BUT TIMING AND PLACEMENT ISSUES STILL REMAIN. WE WILL SEE PERIODIC QUICK MOVING CLIPPER TYPE SYSTEMS TRACK SOUTHEAST THROUGH THE LOCAL AREA LATE IN THE WORK WEEK AND INTO NEXT WEEKEND...WITH NO BIG WARM-UPS IN STORE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 316 AM CDT SUN APR 27 2014 CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS WESTERN AND CENTRAL NORTH DAKOTA THROUGH THIS MORNING. RAIN SHOWER AND THUNDERSTORM ACTIVITY WILL BECOME MORE WIDESPREAD WITH CEILINGS LOWERING INTO THE MVFR RANGE. EXPECT WIDESPREAD MVFR CONDITIONS IN RAIN AND STRATUS THROUGH THE DAY ON SUNDAY...POSSIBLY LOWERING NEAR IFR AFTER SUNSET. STRONG EASTERLY WINDS WILL CONTINUE TODAY FOR CENTRAL NORTH DAKOTA && .HYDROLOGY... ISSUED AT 316 AM CDT SUN APR 27 2014 WIDESPREAD BETWEEN ONE AND TWO INCHES OF RAIN IS FORECAST ACROSS THE AREA WITH UP TO THREE INCHES IN SOUTHWEST NORTH DAKOTA. THIS COULD HAVE SIGNIFICANT IMPACTS IN BASIN HYDROLOGIC RESPONSE. LIMITING FACTORS IN RIVER RESPONSE WILL BE THAT THE FROST IS OUT OF THE GROUND...AND IT HAS BEEN DRY. SOILS WILL BE ABLE TO ABSORB A LOT OF THE RAIN...BUT NOT ALL OF IT. THAT SAID...STREAM AND RIVER RISES...POSSIBLY ABOVE MINOR FLOOD STAGE...ARE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005-013-023-025- 036-037-047-048-050-051. && $$ SHORT TERM...AYD LONG TERM...TWH AVIATION...AYD HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1258 AM CDT SUN APR 27 2014 .UPDATE... ISSUED AT 1258 AM CDT SUN APR 27 2014 WILL FOLLOW CLOSELY TO 04 UTC HRRR FOR POPS THE REMAINDER OF THE NIGHT AND SUNDAY MORNING AS IT HAS DONE WELL THROUGH THE OVERNIGHT THUS FAR. AS OF 06 UTC...A BAND OF LIGHT TO MODERATE RAIN SHOWERS CONTINUES TO PROPAGATE NORTH INTO THE US HIGHWAY 2 CORRIDOR. FURTHER SOUTH...ISOLATED THUNDERSTORMS WERE DEVELOPING NEAR THE SOUTH DAKOTA BORDER ALONG AND EAST OF THE MISSOURI RIVER ON THE NORTHERN FRINGES OF THE ELEVATED INSTABILITY. FOLLOWING THE HRRR...EXPECT THE WAVE ACROSS CENTRAL SOUTH DAKOTA TO CONTINUE TO LIFT NORTH...LEADING TO AN INCREASE IN SHOWER AND THUNDERSTORM COVERAGE FROM 09-12 UTC ALONG AND SOUTH OF I-94. THEREAFTER...RAIN BECOMES FOCUSED ACROSS SOUTHWEST NORTH DAKOTA ALONG THE INVERTED TROUGH...WITH A POTENTIAL LULL IN RAIN CENTRAL DURING THE MID TO LATE MORNING. UPDATE ISSUED AT 1010 PM CDT SAT APR 26 2014 WIND ADVISORY WAS ALLOWED TO EXPIRE WEST...BUT CONTINUED AND EXPANDED CENTRAL AND EAST THROUGH SUNDAY. BISMARCK WAS STILL GUSTING TO 45 MPH LAST OBSERVATION. IT WILL BE BORDERLINE ADVISORY CRITERIA OVER THE COUNTIES WEST OF THE MISSOURI...MORTON...OLIVER ON SUNDAY BUT CLOSE ENOUGH TO WARRANT KEEPING IT GOING. MESOSCALE MODELS DEPICT THE BAND OF SHOWERS IN EASTERN NORTH DAKOTA MOVING OUT THE NEXT FEW HOURS AND ANOTHER...LARGER...BAND DEVELOPING IN CENTRAL SOUTH DAKOTA AND MOVING INTO THE FORECAST AREA AFTER 2-3 AM SUNDAY. UPDATE ISSUED AT 645 PM CDT SAT APR 26 2014 WILL NEED TO ADD EVENING POPS TO THE ZONES EAST OF A LINE FROM BISMARCK TO MINOT. ELEVATED CONVECTION WAS INITIATING IN NORTHEAST SOUTH DAKOTA ALONG AN AXIS OF MOST UNSTABLE CAPE AS DEPICTED ON THE MESOSCALE ANALYSIS. NWS ABERDEEN HAS HAD REPORTS OF PEA SIZE HAIL WITH THE STRONGER STORMS EAST OF ABERDEEN SOUTH DAKOTA. WIND SPEEDS WARRANT KEEPING THE WIND ADVISORIES IN PLACE. NO OTHER CHANGES THIS UPDATE CYCLE. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 343 PM CDT SAT APR 26 2014 THE HIGHLIGHTS OF THE SHORT TERM INCLUDE STRONG WINDS AND PRECIPITATION POTENTIAL. CURRENTLY...THE NARROW BAND OF SHOWERS HAS LIFTED INTO THE FAR NORTH CENTRAL COUNTIES NORTH OF MINOT TO THE DEVILS LAKE BASIN AND WAS MOVING INTO THE TURTLE MOUNTAIN AREA. THIS BAND OF SHOWERS SHOULD BE NORTH OF THE CANADIAN BORDER BY THE EVENING. A LARGE UPPER LEVEL TROUGH EXTENDED ALONG THE NORTH AMERICAN ROCKIES...WITH A SURFACE LOW OVER EASTERN COLORADO AND ONE OVER FAR SOUTHEASTERN MONTANA. STRONG EAST-SOUTHEAST WINDS HAD BEEN INCREASING ACROSS NORTH DAKOTA...AND HAD ISSUED A WIND ADVISORY FOR THE AFTERNOON AND EVENING HOURS FOR COUNTIES MAINLY SOUTH AND WEST OF THE MISSOURI RIVER...BUT ALSO INCLUDING A FEW COUNTIES IN THE FAR SOUTH CENTRAL. FOR WINDS TONIGHT...THE LATEST MODELS AND MODEL GUIDANCE INDICATE A MORE INTENSE SURFACE LOW AND SUPPORTING SURFACE TO MID-LEVEL WINDS THAT SHOULD RESULT IN STRONGER WINDS THAN EARLIER FORECAST. WILL EXPAND THE WIND ADVISORY EASTWARD FOR TONIGHT TO INCLUDE THE JAMES RIVER BASIN BEGINNING AFTER 10 PM CDT...AND THE WIND ADVISORY ON SUNDAY WILL INCLUDE EMMONS COUNTY TO PIERCE AND ROLETTE COUNTY AND EASTWARD. IN SUMMARY FOR WINDS...STRONGEST WINDS IN THE SOUTHWEST TODAY/THIS EVENING TRANSITIONING TO THE SOUTH CENTRAL OVERNIGHT AND INTO THE EASTERN HALF OF THE STATE DAYTIME ON SUNDAY. THE STRONG SURFACE LOWS MERGE/DEVELOP INTO ONE LARGE SURFACE SYSTEM BY DAYBREAK SUNDAY...CENTERED AROUND EASTERN COLORADO/WESTERN KANSAS/WESTERN NEBRASKA. LITTLE MOVEMENT EASTWARD DURING THE DAY ON SUNDAY...WITH THE LOW CENTERED OVER CENTRAL/EASTERN NEBRASKA BY SUNDAY EVENING. EXPECTING SHOWERS AND POSSIBLE THUNDERSTORMS POSSIBLE OVER SOUTHWESTERN NORTH DAKOTA EARLY IN THE EVENING...BUT BY LATE EVENING/MIDNIGHT THE BEST CHANCES ARE STILL IN THE SOUTHWEST. LATER TONIGHT/TOWARDS DAYBREAK THE INSTABILITY ALOFT...ISENTROPIC LIFT NORTH OF THE INTENSE SURFACE LOW...AND PLENTY OF LOW LEVEL MOISTURE ARRIVE IN NORTH DAKOTA - ALL INGREDIENTS COME TOGETHER FOR WIDESPREAD OUTBREAK OF RAIN SHOWERS ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA...WHICH CONTINUES THROUGH SUNDAY AND INTO THE LONG TERM PORTION OF THE FORECAST. THERE WILL ALSO BE A CHANCE THAT THUNDERSTORMS COULD BE EMBEDDED IN THE SHOWERS MAINLY ACROSS THE SOUTH HALF OF NORTH DAKOTA TONIGHT AND SUNDAY. 1 TO 2 INCHES OF LIQUID PRECIPITATION ARE FORECAST FOR A LARGE PORTION OF WESTERN AND CENTRAL NORTH DAKOTA BEGINNING TONIGHT AND CONTINUING THROUGH DAYBREAK TUESDAY MORNING. AT THIS TIME IT APPEARS THAT THE SOUTHWEST PORTION OF THE STATE IS POISED TO RECEIVE THE HIGHEST AMOUNTS...WITH 2 TO 3 INCHES POSSIBLE IN THE FAR SOUTHWEST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 335 PM CDT SAT APR 26 2014 NOT QUITE DONE WITH WINTER WEATHER YET. A CLOSED UPPER LOW WILL EJECT FROM THE CENTRAL PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES BY THURSDAY EVENING...AND THIS WILL BE THE DOMINATE HEADLINE IN THE EXTENDED WITH A RAIN EVENT...THEN SOME SNOW MONDAY NIGHT AND TUESDAY. ONGOING WET/COOL PATTERN SUNDAY NIGHT WILL CONTINUE INTO TUESDAY BEFORE PRECIPITATION WANES FROM NORTHEAST TO SOUTHWEST DURING THE AFTERNOON. HOWEVER THERE MAY BE ADDITIONAL LIGHT BANDS OF PRECIPITATION FOR WEDNESDAY/WEDNESDAY NIGHT ACROSS CENTRAL NORTH DAKOTA AS ANOTHER LOBE OF ENERGY ROTATES AROUND THE UPPER LOW AND INTO THE NORTHERN HIGH PLAINS. H85 TEMPS ON BOTH THE GFS AND ECMWF...(-2C TO -4C) ALONG WITH THE GFS SOUNDINGS...INDICATE ANY PRECIPITATION FALLING MONDAY NIGHT INTO TUESDAY MORNING WILL BE IN THE FORM OF SNOW ACROSS WESTERN AND CENTRAL NORTH DAKOTA. PRIOR TO THIS...SUNDAY NIGHT INTO MONDAY MORNING....THE THREAT OF A SNOW/RAIN MIX IS MOST PREVALENT ACROSS NORTH CENTRAL AND NORTHWEST NORTH DAKOTA IN CONCERT WITH SUBZERO 850MB TEMPS AND SUFFICIENT AMOUNTS OF PRECIPITATION FORECAST. MAIN UPDATE TO THE ALLBLEND WAS TO SIGNIFICANTLY LOWER HIGHS TUESDAY. WITH CLOUDS AND MOSTLY SNOW OCCURRING FOR MOST OF THE MORNING INTO THE EARLY AFTERNOON...ALONG WITH A NORTHERLY FLOW ADVECTING IN H85 TEMPS BELOW ZERO (-2C TO -4C)...JUST CANNOT FOLLOW THE ALLBLEND FORECAST OF HIGHS WELL INTO THE 40S AND LOWER 50S. HAVE CUT THESE BY ROUGHLY 10 DEGREES...THINKING THAT MOST AREAS WILL REMAIN IN MID TO UPPER 30S FOR MOST OF THE DAY...THEN POSSIBLY RISING TO AROUND 40 AS THE PRECIPITATION TAPERS OFF FROM NORTHEAST TO SOUTHWEST. DRIER AIR IN THE TURTLE MOUNTAINS WILL BEGIN NOSING INTO CENTRAL NORTH DAKOTA IN THE AFTERNOON WITH PERHAPS A FEW BREAKS IN THE CLOUD COVER. HOWEVER CLOUDS AND PRECIPITATION ARE FORECAST TO CONTINUE IN THE SOUTHWEST THROUGH TUESDAY AFTERNOON. ANOTHER HIGHLIGHT...WET SNOWFALL ACCUMULATION POTENTIAL MONDAY NIGHT THROUGH TUESDAY MORNING WILL NEED TO BE MONITORED. LATEST ECMWF HAS H85 TEMPS OF -4C WITH WIDESPREAD PRECIPITATION CONTINUING FROM 06Z THROUGH 18Z TUESDAY. WITH ACTUAL AIR TEMPS IN THE MID 30S AND WET BULB TEMPS ABOVE 32F...SNOWFALL RATES WOULD HAVE TO BECOME FAIRLY HEAVY TO ACCUMULATE SIGNIFICANTLY ON ROADS...A BIT EASIER ON GRASSY AREAS WITH A COUPLE INCHES POSSIBLE. THE WINTER WEATHER DESK ON DAY 3 WHICH INCLUDES THE MONDAY NIGHT INTO TUESDAY TIME FRAME HAS POCKETS OF 1 TO 2 INCHES AND SOME 2 TO 4 INCH SNOWFALL AMOUNTS OVER THE NORTHWEST AND NORTH CENTRAL. THIS SEEMS PLAUSIBLE GIVEN THE DEEP COLD AIR ALOFT AND SHALLOW ABOVE FREEZING LAYER NEAR THE GROUND. OUR LATEST GRIDS HAVE 1 TO 1.5 INCHES OF SNOWFALL IN THE NORTHWEST AND NORTH CENTRAL AND WILL USE THIS AS A STARTING POINT. THIS WILL LIKELY BE ADJUSTED IN THE FUTURE AS THE AMOUNT/AREAL COVERAGE OF PRECIPITATION COINCIDING WITH SUBZERO 850 TEMPS BECOMES CLEARER. TREND IS FOR A BREAK IN THE PRECIPITATION TUESDAY NIGHT FOLLOWED BY ANOTHER ROUND OF LIGHT RAIN/SNOW WEDNESDAY CENTRAL INCLUDING THE JAMES RIVER VALLEY. BRISK NORTHERLY WINDS OF 20 TO 30 MPH CAN ALSO BE EXPECTED WITH HIGHS IN THE 40S AS A 850MB COLD POCKET OF -2C REMAINS OVERHEAD. THE GFS MAINTAINS SOME CHANCES OF PRECIPITATION CONTINUING INTO THURSDAY FOR CENTRAL NORTH DAKOTA WITH ANOTHER BRISK AND CHILLY DAY. FOR FRIDAY AND SATURDAY...STILL SOME UNCERTAINTY ON THE UPPER AIR PATTERN WITH THE ECMWF ADVERTISING A MORE AGGRESSIVE COOLING TREND WITH ANOTHER SYSTEM SLATED FOR SATURDAY. THE 12Z GFS IS BEGINNING TO SHOW SOME SIGNATURE OF THIS. APPEARS SPRINGTIME TEMPERATURES WILL REMAIN ON THE BACK BURNER FOR AT LEAST THE NEXT SEVEN DAYS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1258 AM CDT SUN APR 27 2014 CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE NIGHT AND INTO SUNDAY MORNING. RAIN SHOWER ACTIVITY WILL BECOME MORE WIDESPREAD WITH CEILINGS LOWERING INTO THE MVFR RANGE. EXPECT WIDESPREAD MVFR CONDITIONS IN RAIN AND STRATUS THROUGH THE DAY ON SUNDAY...POSSIBLY LOWERING NEAR IFR AFTER SUNSET. STRONG EASTERLY WINDS WILL CONTINUE TONIGHT INTO SUNDAY MORNING. && .HYDROLOGY... ISSUED AT 1010 PM CDT SAT APR 26 2014 WIDESPREAD BETWEEN ONE AND TWO INCHES OF RAIN IS FORECAST ACROSS THE AREA WITH UP TO THREE INCHES IN SOUTHWEST NORTH DAKOTA. THIS COULD HAVE SIGNIFICANT IMPACTS IN BASIN HYDROLOGIC RESPONSE. LIMITING FACTORS IN RIVER RESPONSE WILL BE THAT THE FROST IS OUT OF THE GROUND...AND IT HAS BEEN DRY. SOILS WILL BE ABLE TO ABSORB A LOT OF THE RAIN...BUT NOT ALL OF IT. THAT SAID...STREAM AND RIVER RISES...POSSIBLY ABOVE MINOR FLOOD STAGE...ARE POSSIBLE. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NDZ004- 005-012-013-019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...KS AVIATION...AYD HYDROLOGY...AYD/KS/JPM
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
442 PM EDT SUN APR 27 2014 .SYNOPSIS... AN APPROACHING STRONG LOW PRESSURE SYSTEM LIFTING SLOWLY THROUGH THE CENTRAL PLAINS AND GREAT LAKES WILL DOMINATE THE WEATHER FOR MUCH OF THE WEEK. A PUSH OF WARM...MOIST AIR AHEAD OF THE SYSTEM WILL BRING EPISODES OF SHOWERS AND THUNDERSTORMS FROM LATE TONIGHT THROUGH WEDNESDAY AS THE LOW LINGERS OVER THE REGION. A COOLER AND STILL UNSETTLED PATTERN WILL TAKE HOLD FOR THE END OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... FCST AREA STILL FAIRLY DRY AHEAD OF APPROACHING AREA OF SHOWERS WITH THE CONTINUED EASTERLY WIND AND DRY LOW LEVELS. HRRR IS TRENDING WITH DIMINISHING THE TSRA CURRENTLY OVER SW IN/SE IL/W KY AS THE BOUNDARY LIFTS ENE TOWARD AREA. HAVE GENERALLY SLOWLY BUILT CHANCE SHRA WITH SCT TSRA AFTER ESPECIALLY 02Z WITH BETTER MOISTURE ARRIVING IN THE WESTERN FCST AREA IN THE 06/12Z TIMEFRAME. PW VALUES ARE APPROACHING 200 PERCENT OF NORMAL TOWARD 12Z...BUT THIS BAND WILL BE FAIRLY PROGRESSIVE AND AM NOT CONCERNED WITH TRW+ ISSUES WITH THIS FIRST ROUND. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... WITH THE FIRST PUSH OF MOISTURE TO LIFT THROUGH THE FCST AREA IN THE 12-18Z TIMEFRAME. A LULL IN THE MORE WIDESPREAD PRECIP IN THE AFTERNOON...THOUGH INSTABILITY TO GENERATE STORMS REACHING SEVERE LEVELS MONDAY AFTERNOON IS DEPENDENT ON HOW WORKED OVER OUR AREA BECOMES DUE TO THE MORNING PRECIP. GFS IS MOST AGGRESSIVE WITH MLCAPES IN THE 500-800 J/KG RANGE ACROSS THE SOUTH...WHEREAS THE NAM MUCH LESS AGRESSIVE WITH THE INSTABY. CONVECTION TO DEVELOP ALONG A PREFRONTAL BOUNDARY MONDAY EVENING/NIGHT IN THE SOUTH. WITH THE INCREASING LLJ INTO THE EVENING...SOME INCREASING LL SHEAR...THOUGH BEST INSTABY AND WIND FIELDS INDICATE THE THREAT WILL BE HIGHER FURTHER TO OUR SOUTH. AS THE ENHANCED MOISTURE TRANSPORT SHIFTS THROUGH THE SOUTHERN OHIO VALLEY ALONG WITH AN INTENSIFYING LLJ...OUR SOUTHERN AND EASTERN AREA WILL SEE THE POTENTIAL FOR SOME HEAVY RAIN AS THE SYSTEM. AGAIN THE POTENTIAL IS BEST TO OUR SOUTH...AND CONFIDENCE OF FLASH FLOODING IS NOT HIGH ENOUGH FOR WATCH ATTM. WILL CONTINUE THE HAZARDOUS WEATHER OUTLOOK MENTION OF HEAVY RAIN ALONG WITH THE POSSIBLE SEVERE THREAT MONDAY EVENING. && .LONG TERM /TUESDAY THROUGH SUNDAY/... BLOCKY PATTERN WITH BROAD SLOW MOVING UPPER LEVEL LOW OVER THE NATIONS MID SECTION TO PROGRESS INTO THE GREAT LAKES BY THE END OF THE WEEK. WITH THE UPPER LOW POSITIONED TO OUR WEST...INITIAL SFC FRONT LOOKS TO PUSH THROUGH ON TUESDAY. THERE LOOKS TO BE ONGOING CONVECTION MAINLY OVER THE EAST IN THE MORNING AND THEN RE-DEVELOPMENT DURG THE LATE AFTN IN THE WEST. WILL CONTINUE TO INCLUDE MENTION OF THUNDER WITH VERY MOIST AIRMASS AND MARGINAL INSTBY INDICATED BY MODEL SOLNS. HEAVY RAIN WILL ALSO BE POSSIBLE MAINLY SE EARLY TUESDAY WITH PW/S APPROACHING 200 PERCENT OF NORMAL. SFC LOW PRESSURE TO PIVOT NE AROUND THE UPPER SYSTEM...PASSING NW OF ILN/S FA TUESDAY NIGHT/WEDNESDAY. THIS LOOKS TO PROVIDE ANOTHER ENHANCED CHANCE FOR PRECIPITATION. MODEL SOLNS WORK SOME DRIER AIR INTO ILN/S FA LATER WEDNESDAY AS THE UPPER LOW PIVOTS INTO THE GREAT LAKES. A DECREASING CHANCE FOR SHOWERS WILL CONTINUE THURSDAY INTO FRIDAY WITH THE UPPER LOW POSITIONED TO OUR NORTH. EXPECT SHOWER ACTIVITY TO BECOME MORE DIURNALLY DRIVEN WITH THE BEST CHANCE ACROSS THE NORTH. UPPER LOW OPENS UP AND PIVOTS NE BUT HANG BACK TROF WILL CONTINUE TO AFFECT THE OHIO VALLEY NEXT SATURDAY. THEREFORE...SHOWERS WILL REMAIN POSSIBLE AND WILL CONTINUE LOW POP CHANCE FOR A SHOWER. WET PATTERN TO CONTINUE INTO NEXT SUNDAY WITH NEXT TROF AND ASSOCIATED SFC FRONT DROPPING SE THRU THE GREAT LAKES. TEMP WISE...READINGS TO START OUT A LTL ABOVE NORMAL ON THE WARM SIDE OF THE SYSTEM TUESDAY AND THEN COOL DOWN 10 TO 15 DEGREES BELOW NORMAL THURSDAY/FRIDAY AS A COOLER AIRMASS MOVES INTO THE REGION. SOME MODERATION EXPECTED BY LATE NEXT WEEKEND BUT READINGS ARE EXPECTED TO STILL BE ABOUT 5 DEGREES BELOW NORMAL. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/... VERY DRY EASTERLY FLOW WILL CONTINUE THROUGH THE NEXT 6-8 HOURS ACROSS ALL TAF SITES. CIRRUS AND A LITTLE SCT-BKN MID CLOUD WILL SLOWLY INCREASE LATER THIS AFTERNOON AND THIS EVENING AS MOISTENING BEGINS ALOFT DOWNSTREAM OF DEEP LOW PRESSURE IN THE CNTL HIGH PLAINS. THINKING THAT A SCT-BKN BAND OF SHOWERS WILL DEVELOP THIS EVENING OVER SRN IND/NRN KY AND WORK SLOWLY NORTHEAST TOWARD CVG/LUK WHILE BATTLING RESIDUAL DRY AIR. ALLOWED FOR A BRIEF PERIOD OF SHOWERS AT THESE SITES BUT CONFIDENCE IS NOT THAT GREAT...MAINTAINED THE SMALL TEMPO GROUP AND PUSHED THIS BACK IN TIME IN ACCORDANCE WITH LATEST SHORT TERM GUIDANCE. AT SITES FURTHER NORTH AND EAST...KEPT VFR CONDITIONS OVERNIGHT AND USED VCSH TO ACCOUNT FOR THE UNCERTAINTY. FEEL A LITTLE BETTER ABOUT A BETTER SLUG OF MOISTURE DRIVING A BAND OF SHOWERS ACROSS THE AREA MONDAY MORNING WITH GENERALLY MINOR IMPACTS TO AVIATION. MVFR VIS/CIG CURRENTLY THE WORST THAT IS EXPECTED...AND COULD END UP LARGELY A VFR EVENT GIVEN HOW MUCH MODELS HAVE OVERESTIMATED LOW LEVEL MOISTURE AS OF LATE. EASTERLY WINDS WILL BE MAINTAINED OVERNIGHT WITH A SLIGHT VEERING TO SOUTHEASTERLY LATER TONIGHT AND TOMORROW AND THEN EVENTUALLY TOWARD SOUTH BY LATER TOMORROW AFTERNOON AS WARM FRONT LIFTS NORTH OF THE AREA. OUTLOOK...MVFR AND OCCASIONALLY SOME IFR CONDITIONS POSSIBLE MONDAY NIGHT INTO TUESDAY WITH SHOWERS AND THUNDERSTORMS. MVFR CONDITIONS EXPECTED AT TIMES INTO WEDNESDAY IN CLOUDS/SHOWERS. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...JDR NEAR TERM...JDR SHORT TERM...JDR LONG TERM...AR AVIATION...BINAU
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
151 PM EDT SUN APR 27 2014 .SYNOPSIS... AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL BRING QUIET WEATHER TO THE REGION TODAY. A LARGE...POTENT LOW PRESSURE SYSTEM WILL MOVE OUT OF THE ROCKIES AND INTO THE PLAINS TONIGHT. A PUSH OF WARM...MOIST AIR AHEAD OF THE SYSTEM WILL BRING EPISODES OF SHOWERS AND THUNDERSTORMS FROM LATE TONIGHT ALL THE WAY THROUGH WEDNESDAY. A COOLER AND STILL UNSETTLED PATTERN WILL TAKE HOLD FOR THE END OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... 27.12Z KILN SOUNDING SHOWING PRETTY CLEARLY THE IMPACT OF THE COLD FRONT THAT PASSED THROUGH THE AREA LAST NIGHT. STILL QUITE MILD /+12C/ AT 850MB WITH DRY WESTERLY FLOW BUT RATHER STRONG COOLING OCCURRED OVERNIGHT CENTERED NEAR/BELOW 925MB WITH EAST/NORTHEAST FLOW. SURFACE TEMPS THIS MORNING RUNNING A GOOD 5-10F COOLER THAN YESTERDAY AREA-WIDE...EVEN NEAR 15F OFF OF YESTERDAY MORNING IN WEST CENTRAL OHIO. THIS MAKES MAX TEMP FORECAST TODAY TOUGH...AS DEPTH OF COOL AIR/EASTERLY FLOW DIMINISHES TOWARD AND SOUTH OF THE OHIO RIVER WITH THE NOW STATIONARY FRONT ANALYZED FROM JUST SOUTH OF EVANSVILLE TO SOUTH OF LEXINGTON. RECENT RAP/HRRR ARE EXTREMELY AGGRESSIVE IN PBL MIXING/WARMING SUGGESTING TEMPS SOARING TO NEAR 80F AS FAR NORTH AS WILMINGTON - AND THUS HAVE BEEN IGNORED. THERE IS CONSENSUS AMONG STATISTICAL REGRESSION OF 925MB TEMPS...MOS GUIDANCE...AND RAW 2M TEMPS FROM VARIOUS NWP THAT SUGGESTS GOING TEMPS ARE ON TRACK /NEAR HIGHER END OF MOS/ WITH EXPECTED HIGHS FROM LOW 60S NORTH TO MID 70S FAR SOUTH. THE DRY AIR SHOULD ALLOW FOR GOOD MIXING...JUST NOT TO DEGREE OF RAP BUFR SOUNDINGS. HAVE CONCERNS THOUGH THAT EASTERLY FLOW/SLOW INCREASE IN MID/HIGH CLOUD WILL KEEP MANY AREAS A LITTLE COOLER THAN FCST SO WILL WATCH. OTHER ISSUE IS RAIN CHANCES THIS EVE IN SE IND/NRN KY. SOME RECENT HRRR /NAM-WRF RUNS HAVE BEEN PRETTY BULLISH IN LEADING ARC OF MOISTURE TRANSPORT /THETA-E ADVECTION ALOFT WILL BRING A BAND OF SHRA/ISOLD TSRA INTO THESE AREAS AROUND SUNSET OR JUST AFTER. OTHER STORM SCALE GUIDANCE /OPERATIONAL AND PARALLEL ARW-WRF/ STRONGLY DISAGREES AND BREAKS UP SHRA BEFORE PENETRATING THE FORECAST AREA. DEGREE OF FORCING LOOKS PRETTY ANEMIC...AND AMBIENT LOW LEVEL MOISTURE IS SCANT. DID INCREASE RAIN CHANCES IN FAR SWRN CORNER OF AREA THIS EVENING...BUT DIDN/T ALLOW THAT PUSH TO MAKE IT VERY FAR INTO THE AREA OVERNIGHT...WAITING UNTIL STRONGER PUSH OF MOISTURE/FORCING ON MONDAY MORNING. SO TONIGHT/S RAIN CHANCES ARE HIGHEST IN ERN IND/NRN KY AND TREND DOWNWARD INTO OHIO. && .SHORT TERM /MONDAY THROUGH TUESDAY/... ADDITIONAL UPPER LEVEL ENERGY EJECTING OUT THE DEEP H5 LOW OVER THE CENTER OF THE COUNTRY WILL COMBINE WITH DAYTIME HEATING AND MOISTURE ADVECTION TO PRODUCE AN AREA SHOWERS AND ISOLD STORMS ON MONDAY. THIS INITIAL WAVE OF STORMS SHOULD PUSH NE BY AFTN AND THERE MAY BE A LULL WITH BREAKS OF SUN. SEVERAL MODELS ARE POINTING TOWARDS A SIGNIFICANT PIECE OF ENERGY EJECTING OUT OF THE UPPER LOW MONDAY AFTN. THIS CAUSES A LINE OF CONVECTION THAT AFFECTS THE FA MONDAY NIGHT. TUESDAY IS LOOKING LIKE THE CONVECTION MIGHT NOT BE AS ORGANIZED AS MONDAY AND MONDAY NIGHT. WITH THE H5 LOW BEGINNING TO FILL...THE MODELS DONT EJECT SIGNIFICANT ENERGY UNTIL TUESDAY NIGHT. THIS WILL LEAVE JUST DAYTIME HEATING TO DRIVE THE CONVECTION. ONCE AGAIN...KEPT THE POPS IN CHC CATEGORY BECAUSE OF THIS ON TUESDAY. THE TEMPERATURE GRADIENT WONT BE AS TIGHT FOR HIGHS ON MONDAY AS THERE WERE ON SUNDAY. NRN COUNTIES SHOULD REACH THE UPPER 60S...BUT THE OHIO RIVER COUNTIES WILL STILL BE IN THE MID 70S. BY TUESDAY EVERYONE SHOULD BE IN TH MID 70S. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LARGE SLOW MOVING UPPER LEVEL LOW OVER THE NATIONS MID SECTION TO PROGRESS INTO THE GREAT LAKES BY THE END OF THE WEEK. WITH THE UPPER LOW POSITIONED TO OUR WEST...SFC FRONT LOOKS TO PUSH THROUGH ON TUESDAY. SOME MODEL SOLN DIFFERENCES EXIST REGARDING TIMING...SO UNCERTAINTY EXISTS REGARDING INSTABILITY AND POTENTIAL FOR SEVERE WEATHER. AS THE LOW APPROACHES... WIND FIELDS INCREASE WITH MARGINAL INSTBY INDICATED ON LATEST RUNS. WILL BECOME MORE FAVORABLE FOR HEAVY RAIN...ESPECIALLY ACROSS THE SE IN THE MORNING. SEVERE WEATHER IS A POSSIBILITY WITH THE BEST THREAT ACROSS THE SOUTH BUT THE DEGREE OF THREAT WILL DEPEND ON THE TRACK AND TIMING OF THE APPROACHING LOW/SFC FRONTAL PASSAGE. WILL CONTINUE LKLY POPS DURG TUESDAY IN THE EAST EARLY AND THEN ENTERING THE WEST LATE. MODEL SOLNS WORKING SOME DRIER AIR INTO ILN/S FA WEDNESDAY AS THE UPPER LOW PIVOTS INTO THE GREAT LAKES. WILL LIMIT POPS TO CHANCE CATEGORY. A DECREASING CHANCE FOR SHOWERS WILL CONTINUE THURSDAY INTO FRIDAY WITH THE UPPER LOW POSITIONED TO OUR NORTH. EXPECT SHOWER ACTIVITY TO BECOME MORE DIURNALLY DRIVEN WITH THE BEST CHANCE ACROSS THE NORTH. MODEL DIFFERENCES INCREASE ON HOW FAST THE UPPER LOW OPENS UP NEXT WEEKEND. WILL CONTINUE LOW POP CHANCE FOR A SHOWER WITH THE BEST THREAT ACRS THE NORTH. TEMP WISE...READINGS TO START OUT A LTL ABOVE NORMAL ON THE WARM SIDE OF THE SYSTEM TUESDAY AND THEN COOL DOWN TO CLOSE TO 10 DEGREES BELOW NORMAL THURSDAY/FRIDAY AS A COOLER AIRMASS MOVES INTO THE REGION. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VERY DRY EASTERLY FLOW WILL CONTINUE THROUGH THE NEXT 6-8 HOURS ACROSS ALL TAF SITES. CIRRUS AND A LITTLE SCT-BKN MID CLOUD WILL SLOWLY INCREASE LATER THIS AFTERNOON AND THIS EVENING AS MOISTENING BEGINS ALOFT DOWNSTREAM OF DEEP LOW PRESSURE IN THE CNTL HIGH PLAINS. THINKING THAT A SCT-BKN BAND OF SHOWERS WILL DEVELOP THIS EVENING OVER SRN IND/NRN KY AND WORK SLOWLY NORTHEAST TOWARD CVG/LUK WHILE BATTLING RESIDUAL DRY AIR. ALLOWED FOR A BRIEF PERIOD OF SHOWERS AT THESE SITES BUT CONFIDENCE IS NOT THAT GREAT...MAINTAINED THE SMALL TEMPO GROUP AND PUSHED THIS BACK IN TIME IN ACCORDANCE WITH LATEST SHORT TERM GUIDANCE. AT SITES FURTHER NORTH AND EAST...KEPT VFR CONDITIONS OVERNIGHT AND USED VCSH TO ACCOUNT FOR THE UNCERTAINTY. FEEL A LITTLE BETTER ABOUT A BETTER SLUG OF MOISTURE DRIVING A BAND OF SHOWERS ACROSS THE AREA MONDAY MORNING WITH GENERALLY MINOR IMPACTS TO AVIATION. MVFR VIS/CIG CURRENTLY THE WORST THAT IS EXPECTED...AND COULD END UP LARGELY A VFR EVENT GIVEN HOW MUCH MODELS HAVE OVERESTIMATED LOW LEVEL MOISTURE AS OF LATE. EASTERLY WINDS WILL BE MAINTAINED OVERNIGHT WITH A SLIGHT VEERING TO SOUTHEASTERLY LATER TONIGHT AND TOMORROW AND THEN EVENTUALLY TOWARD SOUTH BY LATER TOMORROW AFTERNOON AS WARM FRONT LIFTS NORTH OF THE AREA. OUTLOOK...MVFR AND OCCASIONALLY SOME IFR CONDITIONS POSSIBLE MONDAY NIGHT INTO TUESDAY WITH SHOWERS AND THUNDERSTORMS. MVFR CONDITIONS EXPECTED AT TIMES INTO WEDNESDAY IN CLOUDS/SHOWERS. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...SITES NEAR TERM...BINAU SHORT TERM...SITES LONG TERM...AR AVIATION...BINAU
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1035 AM EDT SUN APR 27 2014 .SYNOPSIS... AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL BRING QUIET WEATHER TO THE REGION TODAY. A LARGE...POTENT LOW PRESSURE SYSTEM WILL MOVE OUT OF THE ROCKIES AND INTO THE PLAINS TONIGHT. A PUSH OF WARM...MOIST AIR AHEAD OF THE SYSTEM WILL BRING EPISODES OF SHOWERS AND THUNDERSTORMS FROM LATE TONIGHT ALL THE WAY THROUGH WEDNESDAY. A COOLER AND STILL UNSETTLED PATTERN WILL TAKE HOLD FOR THE END OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... 27.12Z KILN SOUNDING SHOWING PRETTY CLEARLY THE IMPACT OF THE COLD FRONT THAT PASSED THROUGH THE AREA LAST NIGHT. STILL QUITE MILD /+12C/ AT 850MB WITH DRY WESTERLY FLOW BUT RATHER STRONG COOLING OCCURRED OVERNIGHT CENTERED NEAR/BELOW 925MB WITH EAST/NORTHEAST FLOW. SURFACE TEMPS THIS MORNING RUNNING A GOOD 5-10F COOLER THAN YESTERDAY AREA-WIDE...EVEN NEAR 15F OFF OF YESTERDAY MORNING IN WEST CENTRAL OHIO. THIS MAKES MAX TEMP FORECAST TODAY TOUGH...AS DEPTH OF COOL AIR/EASTERLY FLOW DIMINISHES TOWARD AND SOUTH OF THE OHIO RIVER WITH THE NOW STATIONARY FRONT ANALYZED FROM JUST SOUTH OF EVANSVILLE TO SOUTH OF LEXINGTON. RECENT RAP/HRRR ARE EXTREMELY AGGRESSIVE IN PBL MIXING/WARMING SUGGESTING TEMPS SOARING TO NEAR 80F AS FAR NORTH AS WILMINGTON - AND THUS HAVE BEEN IGNORED. THERE IS CONSENSUS AMONG STATISTICAL REGRESSION OF 925MB TEMPS...MOS GUIDANCE...AND RAW 2M TEMPS FROM VARIOUS NWP THAT SUGGESTS GOING TEMPS ARE ON TRACK /NEAR HIGHER END OF MOS/ WITH EXPECTED HIGHS FROM LOW 60S NORTH TO MID 70S FAR SOUTH. THE DRY AIR SHOULD ALLOW FOR GOOD MIXING...JUST NOT TO DEGREE OF RAP BUFR SOUNDINGS. HAVE CONCERNS THOUGH THAT EASTERLY FLOW/SLOW INCREASE IN MID/HIGH CLOUD WILL KEEP MANY AREAS A LITTLE COOLER THAN FCST SO WILL WATCH. OTHER ISSUE IS RAIN CHANCES THIS EVE IN SE IND/NRN KY. SOME RECENT HRRR /NAM-WRF RUNS HAVE BEEN PRETTY BULLISH IN LEADING ARC OF MOISTURE TRANSPORT /THETA-E ADVECTION ALOFT WILL BRING A BAND OF SHRA/ISOLD TSRA INTO THESE AREAS AROUND SUNSET OR JUST AFTER. OTHER STORM SCALE GUIDANCE /OPERATIONAL AND PARALLEL ARW-WRF/ STRONGLY DISAGREES AND BREAKS UP SHRA BEFORE PENETRATING THE FORECAST AREA. DEGREE OF FORCING LOOKS PRETTY ANEMIC...AND AMBIENT LOW LEVEL MOISTURE IS SCANT. DID INCREASE RAIN CHANCES IN FAR SWRN CORNER OF AREA THIS EVENING...BUT DIDN/T ALLOW THAT PUSH TO MAKE IT VERY FAR INTO THE AREA OVERNIGHT...WAITING UNTIL STRONGER PUSH OF MOISTURE/FORCING ON MONDAY MORNING. SO TONIGHT/S RAIN CHANCES ARE HIGHEST IN ERN IND/NRN KY AND TREND DOWNWARD INTO OHIO. && .SHORT TERM /MONDAY THROUGH TUESDAY/... ADDITIONAL UPPER LEVEL ENERGY EJECTING OUT THE DEEP H5 LOW OVER THE CENTER OF THE COUNTRY WILL COMBINE WITH DAYTIME HEATING AND MOISTURE ADVECTION TO PRODUCE AN AREA SHOWERS AND ISOLD STORMS ON MONDAY. THIS INITIAL WAVE OF STORMS SHOULD PUSH NE BY AFTN AND THERE MAY BE A LULL WITH BREAKS OF SUN. SEVERAL MODELS ARE POINTING TOWARDS A SIGNIFICANT PIECE OF ENERGY EJECTING OUT OF THE UPPER LOW MONDAY AFTN. THIS CAUSES A LINE OF CONVECTION THAT AFFECTS THE FA MONDAY NIGHT. TUESDAY IS LOOKING LIKE THE CONVECTION MIGHT NOT BE AS ORGANIZED AS MONDAY AND MONDAY NIGHT. WITH THE H5 LOW BEGINNING TO FILL...THE MODELS DONT EJECT SIGNIFICANT ENERGY UNTIL TUESDAY NIGHT. THIS WILL LEAVE JUST DAYTIME HEATING TO DRIVE THE CONVECTION. ONCE AGAIN...KEPT THE POPS IN CHC CATEGORY BECAUSE OF THIS ON TUESDAY. THE TEMPERATURE GRADIENT WONT BE AS TIGHT FOR HIGHS ON MONDAY AS THERE WERE ON SUNDAY. NRN COUNTIES SHOULD REACH THE UPPER 60S...BUT THE OHIO RIVER COUNTIES WILL STILL BE IN THE MID 70S. BY TUESDAY EVERYONE SHOULD BE IN TH MID 70S. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LARGE SLOW MOVING UPPER LEVEL LOW OVER THE NATIONS MID SECTION TO PROGRESS INTO THE GREAT LAKES BY THE END OF THE WEEK. WITH THE UPPER LOW POSITIONED TO OUR WEST...SFC FRONT LOOKS TO PUSH THROUGH ON TUESDAY. SOME MODEL SOLN DIFFERENCES EXIST REGARDING TIMING...SO UNCERTAINTY EXISTS REGARDING INSTABILITY AND POTENTIAL FOR SEVERE WEATHER. AS THE LOW APPROACHES... WIND FIELDS INCREASE WITH MARGINAL INSTBY INDICATED ON LATEST RUNS. WILL BECOME MORE FAVORABLE FOR HEAVY RAIN...ESPECIALLY ACROSS THE SE IN THE MORNING. SEVERE WEATHER IS A POSSIBILITY WITH THE BEST THREAT ACROSS THE SOUTH BUT THE DEGREE OF THREAT WILL DEPEND ON THE TRACK AND TIMING OF THE APPROACHING LOW/SFC FRONTAL PASSAGE. WILL CONTINUE LKLY POPS DURG TUESDAY IN THE EAST EARLY AND THEN ENTERING THE WEST LATE. MODEL SOLNS WORKING SOME DRIER AIR INTO ILN/S FA WEDNESDAY AS THE UPPER LOW PIVOTS INTO THE GREAT LAKES. WILL LIMIT POPS TO CHANCE CATEGORY. A DECREASING CHANCE FOR SHOWERS WILL CONTINUE THURSDAY INTO FRIDAY WITH THE UPPER LOW POSITIONED TO OUR NORTH. EXPECT SHOWER ACTIVITY TO BECOME MORE DIURNALLY DRIVEN WITH THE BEST CHANCE ACROSS THE NORTH. MODEL DIFFERENCES INCREASE ON HOW FAST THE UPPER LOW OPENS UP NEXT WEEKEND. WILL CONTINUE LOW POP CHANCE FOR A SHOWER WITH THE BEST THREAT ACRS THE NORTH. TEMP WISE...READINGS TO START OUT A LTL ABOVE NORMAL ON THE WARM SIDE OF THE SYSTEM TUESDAY AND THEN COOL DOWN TO CLOSE TO 10 DEGREES BELOW NORMAL THURSDAY/FRIDAY AS A COOLER AIRMASS MOVES INTO THE REGION. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... HIGH LEVEL CLOUDS WILL CONTINUE TO SPILL OVER THE ESTABLISHED H5 RIDGE IN PLACE OVER THE OHIO VALLEY TODAY. NORTHEAST WINDS UNDER 10KT WILL TURN EAST AT 10-14KT SHORTLY AFTER DAYBREAK AND PREVAIL THROUGH THE PERIOD. AS THE H5 RIDGE AXIS ORIENTS NW-SE OVER THE REGION...A WAVE OF VORTICITY IS PROGGED ON THE NAM TO FORCE SOME SHOWERS OUT OF THE MID LEVELS AT KCVG/LUK AFTER ABOUT 2-3Z TONIGHT. THE VORT WEAKENS AS IT RUNS INTO THE RIDGE...PRIMARILY NOTED ON THE NAM. SYNOPTIC MODELS SHOW PRECIP OVER FAR SW OH SPREADING NORTHEAST A BIT TOO RAPIDLY FROM 6-12Z. THIS APPEARS TO BE A LITTLE MUCH GIVEN THE ESTABLISHED H5 RIDGE STILL IN PLACE AT 12Z AND A CONTINUED SUSTAINED SFC WIND FROM THE EAST AOA 12KT. DRYING EAST WINDS WILL HELP KEEP ANY CIGS IN THE VFR CATEGORY UNTIL RAIN BEGINS IN EARNEST AROUND DAYBREAK MONDAY. OUTLOOK...MVFR TO IFR CONDITIONS POSSIBLE AT TIMES IN SHOWERS AND THUNDERSTORMS MONDAY INTO TUESDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...SITES NEAR TERM...BINAU SHORT TERM...SITES LONG TERM...AR AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
206 AM EDT SUN APR 27 2014 .SYNOPSIS... A WEAK COLD FRONT WILL STALL NEAR THE OHIO RIVER TONIGHT AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS OVER THE FRONT AND BRINGS CONTINUED QUIET WEATHER THROUGH SUNDAY. A LARGE...POTENT LOW PRESSURE SYSTEM WILL MOVE SLOWLY OUT OF THE ROCKIES INTO THE HIGH PLAINS ON SUNDAY NIGHT AND MONDAY ALLOWING THE STALLED BOUNDARY ALONG THE OHIO RIVER TO RETURN NORTHWARD AS A WARM FRONT. WITH THIS PUSH OF SOUTHERLY AIR...WARMTH AND MOISTURE AND WILL SPREAD NORTHWARD AND BRING UNSETTLED WEATHER THROUGH THE FIRST HALF OF THE WORK WEEK...WITH EPISODES OF SHOWERS AND THUNDERSTORMS ON TAP FROM LATE SUNDAY NIGHT ALL THE WAY THROUGH WEDNESDAY. A COOLER AND STILL UNSETTLED PATTERN WILL TAKE HOLD FOR THE END OF THE WORK WEEK AND INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A WEAK COLD FRONT WILL SAG SOUTH OF THE OHIO RIVER OVERNIGHT... STALLING OUT JUST SOUTH OF THE AREA BY SUNDAY MORNING. THIS WILL ALLOW A RIDGE OF HIGH PRESSURE TO WEDGE SOUTH INTO THE MIDDLE OHIO VALLEY. MEANWHILE...A MID LEVEL RIDGE WILL BUILD INTO THE AREA FROM THE WEST. A MIX OF MID AND HIGH LEVEL CLOUDS WILL ACCOMPANY A WEAK DISTURBANCE MOVING THROUGH THIS RIDGE LATE TONIGHT. THUS...HAVE CONTINUED WITH PARTLY CLOUDY SKIES. TEMPERATURES WILL VARY CONSIDERABLY BEHIND THE FRONT. LOW WILL RANGE FROM THE UPPER 30S NORTHEAST TO THE LOWER 50S SOUTHWEST. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... CURRENT GOES WATER VAPOR LOOPS AND 26.18Z RAP ANALYSIS CLEARLY SHOW POTENT UPPER LOW DIGGING/TURNING EAST NOW THROUGH AZ. THIS HAS INDUCED STRONG DOWNSTREAM RIDGING FROM THE LOWER MS VALLEY NORTHWARD INTO THE DAKOTAS WHILE GREAT LAKES SYSTEM DRIVING THE COLD FRONT MENTIONED ABOVE SLIDES INTO NEW ENGLAND. THE PROGRESSION OF THE LATTER SYSTEM INTO NEW ENGLAND AND THE FORMER SYSTEM OUT INTO COLORADO WILL ALLOW LARGE SCALE/AMPLIFIED RIDGING INTO AND ACROSS THE OHIO VALLEY ON SUNDAY. THESE RISING HEIGHTS WILL ACT TO STALL THE COLD FRONT CURRENTLY SAGGING THROUGH OHIO...WITH THE FRONT SETTING UP SOMEWHERE NEAR/ALONG THE OHIO RIVER. THERE IS A WEALTH OF MID/UPPER LEVEL MOISTURE STREAMING NORTHEASTWARD THROUGH THE NATIONS MIDSECTION IN THE STRONGER SWLY FLOW ON THE WEST SIDE OF THE RIDGE...SO FEEL TOMORROW WILL HAVE MORE CLOUDS THAN TODAY...LIKELY SOME MID LEVEL AC AND CIRRUS AS WARM/MOIST ADVECTION BEGINS FIRST AT THOSE LEVELS THE RIDGE CROSSES THE AREA. UNDERNEATH...WEAK HIGH PRESSURE WILL BE NOSING SOUTHWARD INTO EASTERN OHIO ON SUNDAY PROVIDING A DRY/EASTERLY BREEZE WHICH WILL KEEP TEMPERATURES A LITTLE COOLER THAN SATURDAY ESP NORTH OF THE OHIO RIVER. THERE WILL STILL BE QUITE A TEMP GRADIENT FROM NRN KY /SOUTH OF THE FRONT/ WHERE TEMPS NEAR 80 WILL BE POSSIBLE AGAIN...AND NORTH OF THE FRONT THE FACTOR OF EAST WINDS...MORE CLOUDS...WILL KEEP TEMPS IN THE 60S. COULD BE A SNEAKY BUST DAY IN TERMS OF TEMPS NOT WARMING AS MUCH AS EXPECTED WITH THE EASTERLY FLOW QUITE STRONG THE FURTHER NORTH OF THE OHIO RIVER ONE GOES. FIRST WAVES OF STRONGER THETA-E ADVECTION ARRIVE /850-700MB/ SUNDAY NIGHT AND PRIMARILY IN LATTER HALF OF THIS PERIOD...AS INITIAL PUSH OF MOISTURE TRANSPORT OCCURS AS SURFACE LOW SWINGS OUT INTO NEBRASKA AND DEEPENS AS THE UPPER LOW REACHES MATURITY AND BECOMES CUT OFF. DESPITE MID/UPPER LEVEL RIDGING STILL LARGELY BEING INTACT OVER THE OHIO VALLEY...THERE IS ENOUGH THERMODYNAMIC FORCING WITH THE WARM/MOIST ADVECTION THAT EXPECT A SCT-BKN WAVE OF SHOWERS AND ISOLD STORMS TO EVOLVE LATER SUNDAY EVENING TO OUR WEST AND CROSS THE AREA LATE SUNDAY NIGHT INTO MONDAY MORNING. DON/T SEE MUCH SEVERE THREAT WITH THIS AT ALL...PER 26.12Z GFS/NAM BUFR SOUNDINGS...INSTBY IS MARGINAL /LESS THAN 1000 J/KG/ AND EFFECTIVE SHEAR FOR THE PARCELS ABOVE THE BOUNDARY LAYER IS RATHER WEAK. THESE SHOULD BE ELEVATED STORMS AND MAIN IMPACTS/THREATS WILL BE SMALL HAIL AND/OR LOCALLY HEAVY DOWNPOURS. HAVE CONTINUED THE MENTION OF 60-75% RAIN CHANCES FOR THIS ACTIVITY...AS THERE REMAINS SOME UNCERTAINTY AT LEAST WITH HOW STRONG THE PUSH OF DEEPER MOISTURE IS AND THE REMAINING ANTECEDENT DRY AIRMASS OVER THE FORECAST AREA. ON MONDAY...THIS INITIAL WAVE OF ADVECTION-INDUCED SHOWERS/STORMS SHOULD PUSH NORTHEAST QUICKLY THROUGH THE MORNING AND MAY VERY WELL HAVE A LULL WITH BREAKS OF SUN IN THE AFTERNOON. HARD TO TELL FOR CERTAIN...WITH LARGE UPPER SYSTEM WELL TO THE WEST...THE ABSENCE OF SYNOPTIC FORCING IS RATHER EASY TO SEE. BUT MOIST FLOW AND CONTINUED WARMING OF THE LOWER TROP SHOULD ALLOW INSTABILITY TO BUILD AND THIS DEVELOPING WARM SECTOR MAY VERY WELL BE FILLED WITH A NUMBER OF CLUSTERS OF SHOWERS AND ISOLATED STORMS. SO THE AFTERNOON HOURS ON MONDAY REMAIN UP FOR GRABS...THERE MAY BE LESS RAIN COVERAGE IN THIS TIME PERIOD THAN CURRENT FORECAST DEPICTS. FEELING MORE CONFIDENT THAT CONFLUENT LOW LEVEL FLOW ALONG/EAST OF MS RIVER INTO THE MID OHIO VALLEY WILL IGNITE WITH SHOWERS/STORMS ON MONDAY EVENING AND NIGHT WHICH SHOULD INVOLVE THE LOCAL AREA AS THE NEXT SHORTWAVE SWINGS THROUGH AND EJECTS NORTHEAST OUT OF THE BASE OF THE LARGE CNTL CONUS TROUGH. GIVEN THE DEEP MSLP WAY TO THE WEST...LOW LEVEL WIND FLOWS WILL HAVE SOME COMPONENT OF SOUTHEAST OR EAST-SOUTHEAST TRAJECTORY ON MONDAY AFTN/EVE...AND GIVEN FAST/SWLY MID/UPPER LEVEL FLOW...PRESENTS AN OPPORTUNITY FOR ORGANIZED SEVERE STORMS ESP IN THE SOUTH WHERE BOUNDARY LAYER INSTBY WILL HAVE THE MOST TIME TO BUILD IN WAKE OF MONDAY MORNING ACTIVITY. HOWEVER...POINT FCST BUFR SOUNDINGS SHOW LACK OF DECENT EML TO STEEPEN TROPOSPHERIC LAPSE RATES...AND CAPE IS THUS TALL/SKINNY AND OVERALL INSTBY STILL LOOKING MARGINAL. BUT SHEAR WILL BE GOOD ESP WITH ANY EASTERLY COMPONENT TO THE LOW LEVEL WIND FIELD...SO IF ANY PROLONGED PERIOD OF HEATING DEVELOPS MONDAY AFTERNOON THE SUBSEQUENT THREATS FOR SEVERE GO UP LATE MON AFTN/NIGHT. RIGHT NOW THERE IS ENOUGH UNCERTAINTY NOT TO GET CARRIED AWAY...AND ACTUALLY GIVEN THE THERMODYNAMICS/PWAT ANOMALIES THERE IS JUST AS MUCH CONCERN FOR A BAND OF HEAVY/EXCESSIVE RAINFALL DEPENDING ON WHERE THE CONFLUENCE SETS UP. SO WATCHING THIS PERIOD CLOSELY. DECIDED NOT TO GET CUTE IN THE FORECAST...AND JUST RUNNING A HIGHER CHANCE FOR SHOWERS/STORMS FROM MONDAY THROUGH MONDAY NIGHT GIVEN OVERALL ENSEMBLE PROBS...DEEP MOISTURE...AND ARRIVAL OF TWO WAVES OF FORCING MENTIONED ABOVE. && .LONG TERM /TUESDAY THROUGH SATURDAY/... LARGE SLOW MOVING UPPER LEVEL LOW OVER THE NATIONS MID SECTION TO PROGRESS INTO THE GREAT LAKES BY THE END OF THE WEEK. WITH THE UPPER LOW POSITIONED TO OUR WEST...SFC FRONT LOOKS TO PUSH THROUGH ON TUESDAY. SOME MODEL SOLN DIFFERENCES EXIST REGARDING TIMING...SO UNCERTAINTY EXISTS REGARDING INSTABILITY AND POTENTIAL FOR SEVERE WEATHER. AS THE LOW APPROACHES... WIND FIELDS INCREASE WITH MARGINAL INSTBY INDICATED ON LATEST RUNS. WILL BECOME MORE FAVORABLE FOR HEAVY RAIN...ESPECIALLY ACROSS THE SE IN THE MORNING. SEVERE WEATHER IS A POSSIBILITY WITH THE BEST THREAT ACROSS THE SOUTH BUT THE DEGREE OF THREAT WILL DEPEND ON THE TRACK AND TIMING OF THE APPROACHING LOW/SFC FRONTAL PASSAGE. WILL CONTINUE LKLY POPS DURG TUESDAY IN THE EAST EARLY AND THEN ENTERING THE WEST LATE. MODEL SOLNS WORKING SOME DRIER AIR INTO ILN/S FA WEDNESDAY AS THE UPPER LOW PIVOTS INTO THE GREAT LAKES. WILL LIMIT POPS TO CHANCE CATEGORY. A DECREASING CHANCE FOR SHOWERS WILL CONTINUE THURSDAY INTO FRIDAY WITH THE UPPER LOW POSITIONED TO OUR NORTH. EXPECT SHOWER ACTIVITY TO BECOME MORE DIURNALLY DRIVEN WITH THE BEST CHANCE ACROSS THE NORTH. MODEL DIFFERENCES INCREASE ON HOW FAST THE UPPER LOW OPENS UP NEXT WEEKEND. WILL CONTINUE LOW POP CHANCE FOR A SHOWER WITH THE BEST THREAT ACRS THE NORTH. TEMP WISE...READINGS TO START OUT A LTL ABOVE NORMAL ON THE WARM SIDE OF THE SYSTEM TUESDAY AND THEN COOL DOWN TO CLOSE TO 10 DEGREES BELOW NORMAL THURSDAY/FRIDAY AS A COOLER AIRMASS MOVES INTO THE REGION. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... HIGH LEVEL CLOUDS WILL CONTINUE TO SPILL OVER THE ESTABLISHED H5 RIDGE IN PLACE OVER THE OHIO VALLEY TODAY. NORTHEAST WINDS 5-9KT IN THE NEXT FEW HOURS WILL TURN EAST AT 10-14KT BEFORE DAYBREAK AND PREVAIL THROUGH THE PERIOD. AS THE H5 RIDGE AXIS SETTLES NW-SE OVER THE REGION...A WAVE OF VORTICITY IS BEING PROGGED ON THE NAM TO FORCE SOME SHOWERS OUT OF THE MID LEVELS AT KCVG/LUK AFTER ABOUT 2-3Z TOMORROW NIGHT. THE VORT WEAKENS AS IT RUNS INTO THE RIDGE...PRIMARILY NOTED ON THE NAM. GFS AND EURO SHOW PRECIP OVER FAR SW OH AT 6Z...SPREADING NORTHEAST A BIT TOO RAPIDLY AFTER 6Z. THIS APPEARS TO BE A LITTLE MUCH GIVEN THE ESTABLISHED H5 RIDGE STILL IN PLACE AT 12Z. INCREASING CHANCES OF RAIN AND LOWER CIGS TOWARDS DAYBREAK MONDAY APPEARS TO BE THE BEST FORECAST AT THIS MOMENT IN TIME BUT WILL ONLY AFFECT KCVG AT THIS ISSUANCE. OUTLOOK...MVFR TO IFR CONDITIONS POSSIBLE AT TIMES IN SHOWERS AND THUNDERSTORMS MONDAY INTO TUESDAY NIGHT. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...BINAU NEAR TERM...BINAU/HICKMAN SHORT TERM...BINAU LONG TERM...AR AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
105 AM EDT SUN APR 27 2014 .SYNOPSIS... A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH TONIGHT BEHIND A COLD FRONT NOW MOVING INTO CENTRAL OHIO. THE HIGH WILL SHIFT EAST SUNDAY AS LOW PRESSURE MOVES THROUGH THE CENTRAL PLAINS. THE LOW WILL MOVE SLOWLY EAST EARLY NEXT WEEK REACHING SOUTHERN WISCONSIN ON TUESDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... COLD ADVECTION IS STRENGTHENING OFF OF LAKE ERIE THIS EVENING AS HIGH PRESSURE BUILDS TO THE NORTH. LOW CLOUDS HAVE BEEN EXPANDING ACROSS NE OHIO/NW PA WITH ENOUGH MOISTURE AND WEAK CONVERGENCE TO SUPPORT THE CLOUDS FOR THE EVENING. THE RUC IS DOING A BETTER JOB WITH THE CLOUDS THAN THE NAM/GFS AND SHOWS SOME POSSIBLE EXPANSION OFF THE WEST END OF THE LAKE OVERNIGHT BUT CONFIDENCE IS LOW WITH LESS MOISTURE TO WORK WITH TOWARDS TOLEDO. IT DOES SEEM LIKE SOME BREAKS MAY DEVELOP ACROSS NE OH/NW PA OVERNIGHT AS THE RIDGE EXPANDS. RAISED TEMPS A FEW DEGREES NEAR THE LAKESHORE AND ACROSS NW OHIO WHERE WINDS ARE 10-20 MPH. ORIGINAL DISCUSSION...COLD FRONT IS NOW SOUTH OF THE AREA SHOWN BY A BAND OF CU FROM NEAR AOH TO HLG. BKN-OVC CLOUD HAD REDEVELOPED ACROSS FAR NERN OHIO AND NWRN PA BUT DRIER AIR MIXING IN HAS ALLOWED THESE TO THIN AND TAKE ON MORE OF A DIURNAL LOOK. MAIN CONCERN FOR TONIGHT IS THE CLOUD COVER NORTH IN ONTARIO AND MICHIGAN. WHILE THESE HAVE HAD A HARD TIME WORKING SOUTH TODAY THE NAM SHOWS FAVORABLE JET ENERGY OVER THE AREA SUPPORTING THE CLOUDS SHIFTING INTO THE AREA FOR A FEW HOURS THIS EVENING/EARLY TONIGHT BEFORE MOVING EAST AGAIN OUT OF THE AREA. OTHERWISE SKIES CLEAR TO PC. LOWS NEAR GUIDANCE NUMBERS GENERALLY LOW TO MID 30S. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/... SUNDAY MODELS SHOW THE SURFACE RIDGE SHIFTING EAST AS THE LOW MOVES ACROSS NEBRASKA. MOISTURE WILL BE INCREASING THROUGH THE DAY HOWEVER EXPECT ON BALANCE A PARTLY CLOUDY DAY. SUNDAY NIGHT MOISTURE CONTINUES TO INCREASE. BROUGHT CHANCE POPS TO THE WESTERN COUNTIES AFTER MIDNIGHT. THERE IS SOME ELEVATED CAPE THAT GETS CLOSE TO THE AREA TOWARD MORNING BUT FOR NOW WILL HOLD OFF WITH THUNDER UNTIL MONDAY. AS FOR MONDAY HIGH POPS SUPPORTED AS DEEP MOISTURE COMBINE WITH AFTERNOON CAPES OF 600-800 J/KG (SW COUNTIES) AND DIVERGENCE ALOFT MOVE INTO THE AREA. WILL HAVE CATEGORICAL POPS WEST AND LIKELY POPS ELSEWHERE. LITTLE CHANGE FOR MONDAY NIGHT INTO EARLY TUESDAY WITH INSTABILITY AND DEEP MOISTURE CONTINUING TO STREAM INTO THE AREA FROM THE SOUTH. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... LITTLE CHANGE IN THE EXTENDED FORECAST. BOTH MODELS CONTINUE TO SHOW VERY SLOW MOVING UPPER LOW MOVING INTO THE CENTRAL LAKES WITH A BLOCKING HIGH IN CANADA SETTING UP WEDNESDAY. EXTENDED PERIOD WILL BE COOL AND WET..WITH A SERIES OF LOWS ROTATING ACROSS THE AREA INTO THE WEEKEND. THERE WILL BE PERIODS OF RAIN...BUT TIMING IT IN AND OUT WITH THE SERIES OF TROUGHS THIS FAR OUT IS PRECARIOUS AT BEST. FOR NOW WILL CARRY CHANCE POPS INTO THE WEEKEND. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... PATCHY MVFR STRATOCU APPEARS TO BE GETTING SOME LAKE EFFECT HELP. NOT SURE EXACTLY HOW LONG THIS WILL HANG AROUND BUT WILL ALLOW FOR MORE OF IT A LITTLE LONGER TONIGHT INTO THE FIRST FEW DAYLIGHT HOURS...ESPECIALLY AROUND NE OH AND NW PA. ONCE THE STRATOCU DISSIPATES...SHOULD JUST SEE SCT DAYTIME CU TODAY WITH PATCHY HIGH AND SOME MID CLOUDS THRU 06Z SUN NIGHT. NE WINDS MAY GUST TO 20 KNOTS FOR TOL AND FDY LATER TODAY AS THE PRESSURE GRADIENT TIGHTENS...ADDING TO THE NORMAL PICKUP DUE TO MIXING FROM DAYTIME HEATING. .OUTLOOK...NON VFR PROBABLE AT TIMES FROM MONDAY AFTERNOON INTO THURSDAY IN PRECIPITATION. && .MARINE... LET THE SMALL CRAFT ADVISORY EXPIRE ON THE EAST END OF THE LAKE. CONTINUED THE SMALL CRAFT ADVISORY ON THE WEST END. THE NORTHEAST WINDS AND WAVES WERE INCREASING AND THEN WILL DECREASE AFTER MIDNIGHT. PREVIOUS DISCUSSIONS... BASED ON THE LOCATION OF THE HIGH AND THE FORECASTED NORTHEAST WINDS INCREASING THIS EVENING UPDATED TO ADD A SMALL CRAFT ADVISORY FOR THE WEST END OF LAKE ERIE THROUGH 4 AM SUNDAY. WAVES WILL BE INCREASING TO SMALL CRAFT ADVISORY CRITERIA AFTER DARK. KEPT SMALL CRAFT ADVISORY UP UNTIL THIS EVENING. NORTHWEST WINDS OF 15 TO 20 KNOTS WILL TURN TO THE NORTHEAST AND DIMINISH AFTER SUNSET. IMPROVING CONDITIONS SUNDAY AS HIGH PRESSURE PUSHES SOUTH OVER THE LAKE. WINDS TURN TO THE SOUTH MONDAY AS A WARM FRONT LIFTS NORTH OF THE LAKE. AFTER THAT UNSETTLED CONDITIONS SET UP BY MID WEEK AS LOW PRESSURE MOVES INTO THE CENTRAL LAKES WEDNESDAY AND LINGERS INTO THE WEEKEND. WILL SEE PERIODS OF SMALL CRAFT ADVISORY CRITERIA AS TROUGHS ROTATE ACROSS LAKE ERIE. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SUNDAY FOR LEZ142>146. && $$ SYNOPSIS...TK NEAR TERM...KEC/TK SHORT TERM...TK LONG TERM...DJB AVIATION...ADAMS MARINE...DJB/KIELTYKA
AREA FORECAST DISCUSSION
NWS PORTLAND OR
444 AM PDT SUN APR 27 2014 .SYNOPSIS...A COLD FRONT WILL MOVE THROUGH THE AREA THIS MORNING. COOL AND SHOWERY WEATHER IS EXPECTED TO CONTINUE INTO SUNDAY AS THE MAIN UPPER TROUGH SWINGS THROUGH THE PACIFIC NORTHWEST. A WARM FRONT MAY BRUSH THE FORECAST AREA WITH SOME RAIN MONDAY...BUT A BIG CHANGE TO DRIER AND MUCH WARMER WEATHER IS LIKELY BEHIND IT. BY WEDNESDAY AND THURSDAY...IT IS LOOKING LIKELY THAT INLAND VALLEYS WILL PUSH INTO THE 80S FOR THE FIRST TIME THIS SEASON. && .SHORT TERM...SUNDAY THROUGH TUESDAY...CONCERNS HOVER AROUND SNOW IN THE CASCADES TODAY...MINOR PRECIP CHANCES FOR MONDAY NIGHT...THEN A TRANSITION TO WELL ABOVE AND POSSIBLY NEAR RECORD HIGH TEMPERATURES LATER THIS WEEK. WHILE THE MAIN BAND OF PRECIPITATION HAS MOVED INTO THE CASCADES...WE CONTINUE TO SEE WAVES OF SHOWERS MOVING THROUGH. THE SURFACE FRONT IS STRETCHED OUT AND REMAINS DRAPED ALONG THE COAST. THE FRONT EXTENDS NORTH AND THEN WEST TO THE OCCLUDED SURFACE LOW IN THE GULF OF ALASKA...AND IT WILL CONTINUE TO SPREAD INLAND EARLY THIS MORNING. SANTIAM PASS (4800 FT) IS SNOW COVERED...AND THE PASSES AROUND MT HOOD THAT ARE CLOSER TO 4000 FEET IN ELEVATION LOOK LIKE THEY ARE GETTING SOME ACCUMULATION NOW. SHOWERS WILL CONTINUE INTO TODAY AS A FAIRLY STRONG SOMEWHAT ZONAL UPPER LEVEL JET REMAINS FOCUSED ON SOUTHERN OREGON...WITH SEVERAL DISTURBANCES PROGGED TO PUSH THROUGH LATER THIS MORNING IN THE STRONG WESTERLY FLOW ALOFT. AS THE DAY CONTINUES...SURFACE HIGH PRESSURE WILL BEGIN TO NOSE INTO THE AREA FROM THE SOUTHWEST WHICH WILL BEGIN TO EAT AWAY AT THE SOUTHERN EXTENT OF SHOWER ACTIVITY TODAY. PRECIPITATION IN THE CASCADES WILL BE FALLING AS SNOW. THIS WILL INCLUDE THE PASSES THIS MORNING...THOUGH RATES DO NOT LOOK TO BE HEAVY AT ANY ONE TIME AND ENOUGH TO GET TO 6" OTHER THAN UP AT THE HIGHEST CASCADE ELEVATIONS. GFS HAS SLIGHTLY HIGHER INSTABILITY PARAMETERS THAN THE OTHER SHORT TERM. RAP SHOWS LESS THAN 200 J/KG AND IS MAXIMIZED IN THE NORTH. THIS LOOKS TO BE THE SET UP FOR SHOWERS WITH SMALL HAIL AND IF ONE SHOWER MAINTAINS ITSELF IN THE AFTERNOON...MAYBE A RUMBLE OF THUNDER OR TWO AT MOST. SREF CALIBRATED PROBABILITY OF THUNDER IS 40-50% IN THE NORTHERN TIER...SO WORTHY OF SLIGHT CHANCE MENTION. TEMPS ALOFT WILL BE WARMING FROM SOUTH TO NORTH SO CHANCES ARE SIGNIFICANTLY REDUCED SOUTH OF THE COLUMBIA RIVER. BY TONIGHT THE UPPER JET WILL BE LIFTING NORTH...AND AS THIS OCCURS SURFACE HIGH PRESSURE BECOMES FIRMLY IN CONTROL AND WILL WIDDLE DOWN THE SHOWERS SIGNIFICANTLY. ENOUGH STABILIZATION IN THE LOW LEVELS MAY RESULT IN SOME FOG BY MONDAY MORNING. LATER MONDAY AND MONDAY NIGHT...THE INITIAL SIGNS OF OUR UPCOMING WEATHER PATTERN CHANGE BECOMES APPARENT AS UPPER LEVEL RIDGING BEGINS TO BUILD ALONG THE COAST. AS THIS AMPLIFICATION IS OCCURRING...UPSTREAM LOW PRESSURE CONTINUES TO DIG. IN THE SOUTHWEST FLOW AHEAD OF THIS LOW...A WARM FRONT WILL APPROACH THE REGION. THERE IS A MODEST MOISTURE FEED OF 1+" PRECIPITABLE WATER VALUES THAT WILL GET PULLED NORTHWARD SOMEWHAT AS THIS IS OCCURRING. THERE IS SOME PRETTY STRONG LOWER LEVEL FRONTOGENESIS INITIALLY WITH THIS WARM FRONT AS WELL...BUT THE FRONT WILL BE RUNNING INTO THE STRENGTHENING RIDGE AND IT WILL START TO WEAKEN INLAND. THE MODELS ARE STILL MIXED ON PRECIPITATION CHANCES WITH THIS FEATURE WITH THE NAM/GFS A BIT MORE AGGRESSIVE...THE ECMWF KEEPS THINGS MAINLY DRY AWAY FROM THE COAST. SO WHILE NAM/GFS/SREF HAVE BEEN SHOWING A TREND TOWARDS SOME LIGHT PRECIP...CAN ONLY GO WITH LOWER END CHANCE POPS AS THE ECMWF KEEPS INLAND AREAS DRY. BEHIND THE FRONT ...SOUTH WINDS WILL PICK UP BRIEFLY ALONG THE COAST. THE QUESTION AFTER THIS IS...HOW WARM WILL IT GET...AND WILL WE NEAR SOME RECORD HIGH TEMPERATURES DURING THE MIDDLE OF THE WEEK. THE UPPER RIDGE WILL TAKE SOME SHAPE OVER THE AREA AND OFFSHORE FLOW WILL BEGIN AS TUESDAY WEARS ON. /KMD .LONG TERM...NO CHANGES...PREVIOUS DISCUSSION UNCHANGED...TUESDAY NIGHT THROUGH SATURDAY... A STRONG UPPER LEVEL RIDGE OVER THE PAC NW WILL BRING DRY AND VERY WARM WEATHER TO THE REGION ON WED AND THU. A THERMALLY INDUCED SURFACE TROUGH IS MODELED TO BRING EASTERLY WIND ON WED...AND MANY INTERIOR LOCATIONS WILL LIKELY BRING AFTERNOON HIGHS INTO THE LOW 80S. IT IS NOT OUT OF THE QUESTION THAT SOME COASTAL SPOTS MAY APPROACH 80 AS WELL. THE SURFACE THERMAL TROUGH LOOKS LIKE IT WILL MOVE ONSHORE THU...LIKELY ALLOWING SOME COOLING ONSHORE FLOW AT THE COAST. BUT DECIDED TO BUMP UP THE INTERIOR TEMPS SEVERAL DEGREES HIGHER THAN WED...WITH HIGHS INTO THE MID 80S. LOOKING AT AREA CLIMATE STATS...IT IS APPEARS POSSIBLE THAT WE MAY MAKE A RUN AT SETTING SOME DAILY MAX TEMP RECORDS ON WED AND THU. BY FRI...THE LATEST MODEL RUNS ARE MOVING THE UPPER LEVEL RIDGE FURTHER EAST...WITH THE SURFACE THERMAL TROF PUSHING EAST OF THE CASCADES. THIS WOULD INDICATE AN INCREASE IN COOLING ONSHORE FLOW. KEPT THE FCST TRENDING IN THIS DIRECTION...BUT INCREASED HIGH TEMPS A BIT AS IT SEEMS THAT THE MODELS ARE OFTEN TOO AGGRESSIVE COOLING THINGS OFF ON THE DAY THAT THE THERMAL TROF IS FCST TO MOVE EAST OF THE REGION. STARTED BRINGING SLIGHT CHANCES FOR PRECIP BACK FRI NIGHT INTO SAT AS AN UPPER LEVEL TROF STARTS TO PUSH IN TO REPLACE THE DEPARTING RIDGE. PYLE && .AVIATION...POST FRONTAL SHOWERS WILL CONTINUE TODAY AND DECREASE THIS EVENING. VFR PREVAILS WITH OCCASIONAL MVFR CIGS IN THE 2000 TO 3000 FT RANGE SO FAR THIS MORNING. MODELS INDICATING MVFR COULD CONTINUE THROUGH 15Z SUN. BELIEVE MVFR CONDITIONS WILL BE SHORT LIVED AND NOT NEEDED AT MOST TAF LOCATIONS. FOR LATER TONIGHT INTO EARLY MONDAY MORE STABLE CONDITIONS MAY BRING PATCHY FOG AND LOW STRATUS ESPECIALLY SOUTH OF KSLE WHERE ONSHORE FLOW WILL BE WEAKEST. KPDX AND APPROACHES...VFR PREVAILING TODAY WITH OCCASIONAL MVFR CIGS AROUND 2000 FT THIS MORNING. HEAVIER SHOWERS MOVING THROUGH THE AREA MAY BRING BRIEF VIS RESTRICTIONS DURING THE MORNING HOURS AS WELL. AIR MASS INSTABILTIY INCREASES LATER THIS AFTERNOON AND EVENING FOR THE POSSIBILITY OF SOME STRONGER SHOWERS DEVELOPING HAIL OR A LIGHTNING STRIKE OR TWO. CONFIDENCE NOT HIGH ENOUGH TO INCLUDE MENTION OF THUNDER 9 HOURS OUT...BUT WILL MONITOR AND MAKE SHORT TERM UPDATES AS NEEDED. && .MARINE...GUSTY WESTERLY WIND WILL CONTINUE THROUGH EARLY MORNING BEFORE EASING. HIGH PRES BUILD OVER THE WATERS LATER TODAY AND MON. ON SAT MODELS PICKED UP ON A NEW FEATURE FOR MON AND CONTINUE WITH THIS TREND THIS MORNING. WHILE THERE ARE SOME DIFFERENCES IN THE MODELS...THE GENERAL IDEA IS TO ROTATE A WARM FRONT TO THE WATERS MON AFTERNOON AND NIGHT. THIS MAY BRING SMALL CRAFT SOUTH- SOUTHEASTERLY WINDS ESPECIALLY FOR THE OUTER MARINE ZONES. HIGH PRES BUILDS TUE WITH A THERMAL TROUGH MOVING NORTH OVER THE WATERS WED. SEAS WILL CONTINUE A TRANSITION FROM WINDWAVE DOMINATED TO FRESH SWELL THEN FINALLY LONGER PERIOD WESTERLY SWELL TODAY. SEAS APPEAR TO REMAIN 10 TO 12 FEET THROUGH AT LEAST MONDAY AFTERNOON. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM PDT THIS MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT MONDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 8 AM PDT THIS MORNING. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 PM THIS AFTERNOON TO 7 PM PDT THIS EVENING. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA..
AREA FORECAST DISCUSSION
NWS PORTLAND OR
323 AM PDT SUN APR 27 2014 .SYNOPSIS...A COLD FRONT WILL MOVE THROUGH THE AREA THIS MORNING. COOL AND SHOWERY WEATHER IS EXPECTED TO CONTINUE INTO SUNDAY AS THE MAIN UPPER TROUGH SWINGS THROUGH THE PACIFIC NORTHWEST. A WARM FRONT MAY BRUSH THE FORECAST AREA WITH SOME RAIN MONDAY...BUT A BIG CHANGE TO DRIER AND MUCH WARMER WEATHER IS LIKELY BEHIND IT. BY WEDNESDAY AND THURSDAY...IT IS LOOKING LIKELY THAT INLAND VALLEYS WILL PUSH INTO THE 80S FOR THE FIRST TIME THIS SEASON. && .SHORT TERM...SUNDAY THROUGH TUESDAY...CONCERNS HOVER AROUND SNOW IN THE CASCADES TODAY...MINOR PRECIP CHANCES FOR MONDAY NIGHT...THEN A TRANSITION TO WELL ABOVE AND POSSIBLY NEAR RECORD HIGH TEMPERATURES LATER THIS WEEK. WHILE THE MAIN BAND OF PRECIPITATION HAS MOVED INTO THE CASCADES...WE CONTINUE TO SEE WAVES OF SHOWERS MOVING THROUGH. THE SURFACE FRONT IS STRETCHED OUT AND REMAINS DRAPED ALONG THE COAST. THE FRONT EXTENDS NORTH AND THEN WEST TO THE OCCLUDED SURFACE LOW IN THE GULF OF ALASKA...AND IT WILL CONTINUE TO SPREAD INLAND EARLY THIS MORNING. SANTIAM PASS (4800 FT) IS SNOW COVERED...AND THE PASSES AROUND MT HOOD THAT ARE CLOSER TO 4000 FEET IN ELEVATION LOOK LIKE THEY ARE GETTING SOME ACCUMULATION NOW. SHOWERS WILL CONTINUE INTO TODAY AS A FAIRLY STRONG SOMEWHAT ZONAL UPPER LEVEL JET REMAINS FOCUSED ON SOUTHERN OREGON...WITH SEVERAL DISTURBANCES PROGGED TO PUSH THROUGH LATER THIS MORNING IN THE STRONG WESTERLY FLOW ALOFT. AS THE DAY CONTINUES...SURFACE HIGH PRESSURE WILL BEGIN TO NOSE INTO THE AREA FROM THE SOUTHWEST WHICH WILL BEGIN TO EAT AWAY AT THE SOUTHERN EXTENT OF SHOWER ACTIVITY TODAY. PRECIPITATION IN THE CASCADES WILL BE FALLING AS SNOW. THIS WILL INCLUDE THE PASSES THIS MORNING...THOUGH RATES DO NOT LOOK TO BE HEAVY AT ANY ONE TIME AND ENOUGH TO GET TO 6" OTHER THAN UP AT THE HIGHEST CASCADE ELEVATIONS. GFS HAS SLIGHTLY HIGHER INSTABILITY PARAMETERS THAN THE OTHER SHORT TERM. RAP SHOWS LESS THAN 200 J/KG AND IS MAXIMIZED IN THE NORTH. THIS LOOKS TO BE THE SET UP FOR SHOWERS WITH SMALL HAIL AND IF ONE SHOWER MAINTAINS ITSELF IN THE AFTERNOON...MAYBE A RUMBLE OF THUNDER OR TWO AT MOST. SREF CALIBRATED PROBABILITY OF THUNDER IS 40-50% IN THE NORTHERN TIER...SO WORTHY OF SLIGHT CHANCE MENTION. TEMPS ALOFT WILL BE WARMING FROM SOUTH TO NORTH SO CHANCES ARE SIGNIFICANTLY REDUCED SOUTH OF THE COLUMBIA RIVER. BY TONIGHT THE UPPER JET WILL BE LIFTING NORTH...AND AS THIS OCCURS SURFACE HIGH PRESSURE BECOMES FIRMLY IN CONTROL AND WILL WIDDLE DOWN THE SHOWERS SIGNIFICANTLY. ENOUGH STABILIZATION IN THE LOW LEVELS MAY RESULT IN SOME FOG BY MONDAY MORNING. LATER MONDAY AND MONDAY NIGHT...THE INITIAL SIGNS OF OUR UPCOMING WEATHER PATTERN CHANGE BECOMES APPARENT AS UPPER LEVEL RIDGING BEGINS TO BUILD ALONG THE COAST. AS THIS AMPLIFICATION IS OCCURRING...UPSTREAM LOW PRESSURE CONTINUES TO DIG. IN THE SOUTHWEST FLOW AHEAD OF THIS LOW...A WARM FRONT WILL APPROACH THE REGION. THERE IS A MODEST MOISTURE FEED OF 1+" PRECIPITABLE WATER VALUES THAT WILL GET PULLED NORTHWARD SOMEWHAT AS THIS IS OCCURRING. THERE IS SOME PRETTY STRONG LOWER LEVEL FRONTOGENESIS INITIALLY WITH THIS WARM FRONT AS WELL...BUT THE FRONT WILL BE RUNNING INTO THE STRENGTHENING RIDGE AND IT WILL START TO WEAKEN INLAND. THE MODELS ARE STILL MIXED ON PRECIPITATION CHANCES WITH THIS FEATURE WITH THE NAM/GFS A BIT MORE AGGRESSIVE...THE ECMWF KEEPS THINGS MAINLY DRY AWAY FROM THE COAST. SO WHILE NAM/GFS/SREF HAVE BEEN SHOWING A TREND TOWARDS SOME LIGHT PRECIP...CAN ONLY GO WITH LOWER END CHANCE POPS AS THE ECMWF KEEPS INLAND AREAS DRY. BEHIND THE FRONT ...SOUTH WINDS WILL PICK UP BRIEFLY ALONG THE COAST. THE QUESTION AFTER THIS IS...HOW WARM WILL IT GET...AND WILL WE NEAR SOME RECORD HIGH TEMPERATURES DURING THE MIDDLE OF THE WEEK. THE UPPER RIDGE WILL TAKE SOME SHAPE OVER THE AREA AND OFFSHORE FLOW WILL BEGIN AS TUESDAY WEARS ON. /KMD .LONG TERM...NO CHANGES...PREVIOUS DISCUSSION UNCHANGED...TUESDAY NIGHT THROUGH SATURDAY... A STRONG UPPER LEVEL RIDGE OVER THE PAC NW WILL BRING DRY AND VERY WARM WEATHER TO THE REGION ON WED AND THU. A THERMALLY INDUCED SURFACE TROUGH IS MODELED TO BRING EASTERLY WIND ON WED...AND MANY INTERIOR LOCATIONS WILL LIKELY BRING AFTERNOON HIGHS INTO THE LOW 80S. IT IS NOT OUT OF THE QUESTION THAT SOME COASTAL SPOTS MAY APPROACH 80 AS WELL. THE SURFACE THERMAL TROUGH LOOKS LIKE IT WILL MOVE ONSHORE THU...LIKELY ALLOWING SOME COOLING ONSHORE FLOW AT THE COAST. BUT DECIDED TO BUMP UP THE INTERIOR TEMPS SEVERAL DEGREES HIGHER THAN WED...WITH HIGHS INTO THE MID 80S. LOOKING AT AREA CLIMATE STATS...IT IS APPEARS POSSIBLE THAT WE MAY MAKE A RUN AT SETTING SOME DAILY MAX TEMP RECORDS ON WED AND THU. BY FRI...THE LATEST MODEL RUNS ARE MOVING THE UPPER LEVEL RIDGE FURTHER EAST...WITH THE SURFACE THERMAL TROF PUSHING EAST OF THE CASCADES. THIS WOULD INDICATE AN INCREASE IN COOLING ONSHORE FLOW. KEPT THE FCST TRENDING IN THIS DIRECTION...BUT INCREASED HIGH TEMPS A BIT AS IT SEEMS THAT THE MODELS ARE OFTEN TOO AGGRESSIVE COOLING THINGS OFF ON THE DAY THAT THE THERMAL TROF IS FCST TO MOVE EAST OF THE REGION. STARTED BRINGING SLIGHT CHANCES FOR PRECIP BACK FRI NIGHT INTO SAT AS AN UPPER LEVEL TROF STARTS TO PUSH IN TO REPLACE THE DEPARTING RIDGE. PYLE && .AVIATION...POST FRONTAL SHOWERS WILL CONTINUE TODAY AND DECREASE THIS EVENING. VFR PREVAILS WITH OCCASIONAL MVFR CIGS IN THE 2000 TO 3000 FT RANGE SO FAR THIS MORNING. MODELS INDICATING MVFR COULD CONTINUE THROUGH 15Z SUN. BELIEVE MVFR CONDITIONS WILL BE SHORT LIVED AND NOT NEEDED AT MOST TAF LOCATIONS. FOR LATER TONIGHT INTO EARLY MONDAY MORE STABLE CONDITIONS MAY BRING PATCHY FOG AND LOW STRATUS ESPECIALLY SOUTH OF KSLE WHERE ONSHORE FLOW WILL BE WEAKEST. KPDX AND APPROACHES...VFR PREVAILING TODAY WITH OCCASIONAL MVFR CIGS AROUND 2000 FT THIS MORNING. HEAVIER SHOWERS MOVING THROUGH THE AREA MAY BRING BRIEF VIS RESTRICTIONS DURING THE MORNING HOURS AS WELL. && .MARINE...GUSTY WESTERLY WIND WILL CONTINUE THROUGH EARLY MORNING BEFORE EASING. HIGH PRES BUILD OVER THE WATERS LATER TODAY AND MON. ON SAT MODELS PICKED UP ON A NEW FEATURE FOR MON AND CONTINUE WITH THIS TREND THIS MORNING. WHILE THERE ARE SOME DIFFERENCES IN THE MODELS...THE GENERAL IDEA IS TO ROTATE A WARM FRONT TO THE WATERS MON AFTERNOON AND NIGHT. THIS MAY BRING SMALL CRAFT SOUTH- SOUTHEASTERLY WINDS ESPECIALLY FOR THE OUTER MARINE ZONES. HIGH PRES BUILDS TUE WITH A THERMAL TROUGH MOVING NORTH OVER THE WATERS WED. SEAS WILL CONTINUE A TRANSITION FROM WINDWAVE DOMINATED TO FRESH SWELL THEN FINALLY LONGER PERIOD WESTERLY SWELL TODAY. SEAS APPEAR TO REMAIN 10 TO 12 FEET THROUGH AT LEAST MONDAY AFTERNOON. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM PDT THIS MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT MONDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 8 AM PDT THIS MORNING. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 PM THIS AFTERNOON TO 7 PM PDT THIS EVENING. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA..
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1023 PM CDT MON APR 28 2014 .MESOSCALE UPDATE... OHX VWP IS NOW SHOWING SOME VEERING OF THE WIND FIELD WITH TIME IN THE LOWER LEVELS. THUS...THE DRIER AIR IS ON THE WAY. THIS IS FURTHER SUPPORTED BY A CONTINUING DECREASE IN COVERAGE OVER THE AREA. WILL GO AHEAD AND CONTINUE TO LOWER POPS GRADUALLY WITH TIME. OTW...STILL NO IMMEDIATE THREAT ACROSS THE TOR WATCH AREA. ACTIVITY OVER NRN AL IS HAVING A DIFFICULT TIME MAINTAINING ANY STRENGTH. STILL...A LITTLE TOO EARLY TO CANCEL THE WATCH SO WILL LET IT RIDE FOR NOW. FOR THE UPDATE...AGAIN WILL LOWER POPS. && .PREV DISCUSSION... /ISSUED 957 PM CDT MON APR 28 2014/ UPDATE... COVERAGE OVER THE MID STATE HAS DECREASED SOME AND IS MORE BROKEN IN NATURE NOW. INSTABILITY PARAMETERS CONTINUE TO LOOK RATHER WEAK ACROSS WESTERN MIDDLE ALTHOUGH 850 MB WIND IS STILL REASONABLY STRONG. STILL HOWEVER...THE BACK EDGE OF THE PRECIP HAS NOT MADE MUCH OF AN ADVANCEMENT EASTWARD YET. FURTHER EAST...CURRENTLY THE TOR WATCH AREA IS NOT UNDER AN IMMEDIATE THREAT. HOWEVER...WE DO SEE SOME STORM REDEVELOPMENT OVER NW AL AT THIS TIME AND HELICITY VALUES OVER THE WATCH AREA REMAIN ELEVATED. THEREFORE...WILL ELECT TO KEEP THE WATCH GOING FOR NOW. MAY BEGIN TO TAPER POPS ACROSS OUR WEST IN AN HOUR OR TWO...DEPENDING ON FUTURE TRENDS. OTW...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 816 PM CDT MON APR 28 2014/ AVIATION 00Z DISCUSSION... SEVERE WEATHER REMAINS A POSSIBILITY FOR THE CSV AREA. SHOWERS AND TSTMS WILL CONTINUE ACROSS MAINLY THE CSV AND BNA AREAS THROUGH AT LEAST 06Z. SOME OF THE STORMS COULD REACH STRONG OR SEVERE LIMITS NEAR CSV BETWEEN NOW AND 06Z. PRECIP SHOULD END BY 09Z FOR CSV WITH A BREAK UNTIL 18Z ON TUESDAY WHEN TSTMS MAY FIRE UP AGAIN. PREV DISCUSSION... /ISSUED 812 PM CDT MON APR 28 2014/ UPDATE... STRONG TO POTENTIALLY SEVERE TSTMS MARCHING NE ACROSS THE SOUTHERN PLATEAU. LAPS STILL SHOWING AN IMPRESSIVE SLUG OF AMPLIFIED HELICITY ACROSS THIS REGION. ALTHOUGH THE HELICITY STRENGTH IS ON THE DOWN SLIDE. TOR WATCH NUMBER 111 WILL BE ALLOWED TO CONTINUE FOR NOW FOR THOSE 6 COUNTIES IN OUR EAST AND SOUTHEAST. OTW...BACK EDGE OF THE SHOWER AND TSTM ACTIVITY EXTENDS FROM CLARKSVILLE SW THROUGH LOBELVILLE. NO EASTWARD PUSH IS INDICATED AND A SLIGHT WESTWARD PUSH IS INDICATED. MODELS STILL IN AGREEMENT WITH DRIER AIR WINNING OUT LATER TONIGHT. AT SOME POINT OVER THE NEXT FEW HOURS...SHOULD BEGIN TO SEE AN EASTWARD PUSH WITH THE PRECIP SLOWLY ENDING FROM WEST TO EAST. INSTABILITY PARAMETERS CONTINUE TO LOOK TOO WEAK TO SUPPORT SEVERE DEVELOPMENT. BUT...PERHAPS A STRONG STORM OR TWO COULD STILL DEVELOP OVER OUR SOUTHERN COUNTIES OVER THE NEXT HOUR OR TWO. FOR THE FORECAST...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 514 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... LATEST LAPS DATA CLEARLY SHOWS THAT THE BETTER INSTABILITY IS OVER OUR SOUTHERN AREAS WHICH IS WHERE THE TOR WATCH IS IN EFFECT. CAPE VALUES...SHOWALTERS ALL IN SUPPORT OF THE SUBSTANTIAL AMOUNTS OF INSTABILITY ACROSS THE SOUTH. CURRENT RADAR SHOWS THE STRONGEST ACTIVITY FROM DICKSON COUNTY SOUTHWARD THROUGH GILES COUNTY WITH AGAIN...THE STRONGEST ACTIVITY THE FURTHER SOUTH YOU GO. WE DO SEE A LINE OF THUNDERSTORMS ATTEMPTING TO DEVELOP BACK ACROSS WESTERN KY. HOWEVER...THERE IS A DEGREE OF INCREASING CAP STRENGTH ACROSS OUR NORTHERN AREAS. THUS...IT MAY HAVE A TOUGH TIME DEVELOPING INTO SOMETHING MORE SUBSTANTIAL. HRRR FURTHER CONCURS WITH THE IDEA OF NO REDEVELOPMENT TONIGHT TO THE WEST OF THE AFOREMENTIONED STRONGEST CONVECTION. BIGGEST POTENTIAL IMPACT OVER THE NEXT FEW HOURS WILL BE OVER OUR SOUTHERN AREAS WHERE THE POTENTIALLY TORNADIC CELLS COULD CLIP OUR FAR SOUTHERN COUNTIES AND EVENTUALLY OUR SOUTHERN PLATEAU. AS FOR THE FLOOD THREAT...THE FLASH FLOOD WATCH CONTINUES THROUGH TUESDAY EVENING. PREV DISCUSSION... /ISSUED 256 PM CDT MON APR 28 2014/ DISCUSSION... SIGNIFICANT SEVERE WEATHER THREAT STILL EXISTS OVER FAR SOUTHERN MIDDLE TN THROUGH TONIGHT... A STRONG LOW PRESSURE CENTER OVER EASTERN NEBRASKA WILL DRAG A COLD FRONT THROUGH THE REGION LATE TONIGHT...WITH ITS UPPER LOW LAGGING AND SPINNING ACROSS THE UPPER MIDWEST. STRONG DIVERGENCE ALOFT ON THE NOSE OF A 115-KT UPPER JET HAS LED TO AMPLE PRECIP ACROSS MIDDLE TN THIS MORNING THROUGH THE EARLY AFTERNOON HOURS. THIS ACTIVITY HAS LED TO 3-5 INCH RAINFALL AMOUNTS MAINLY WEST OF I-65 AND SOUTH OF I-40...WHERE RESIDUAL FLOODING AND FLASH FLOODING CONTINUE. A FLASH FLOOD WATCH CONTINUES FOR ALL OF MIDDLE TN AND WILL BE EXTENDED THROUGH TUESDAY AFTERNOON GIVEN THE RIVER FLOODING THREAT FROM ADDITIONAL RAINS FROM THIS EVENING THROUGH THE OVERNIGHT HOURS. WILL ISSUE THE UPDATED FLASH FLOOD WATCH SOON. MORE INTERESTINGLY...THE MORNING CONVECTION DROPPED AN OUTFLOW BOUNDARY ACROSS FAR SOUTHERN MIDDLE TN...WHERE POINTS NORTH OF THAT BOUNDARY REMAIN IN THE COLD POOL REGION...AND POINTS ALONG AND SOUTH OF THIS BOUNDARY REMAIN VERY UNSTABLE. THIS BOUNDARY EVEN CURLS BACK TO THE WEST A BIT OVER OUR FAR EASTERN CWA. WITH SFC CAPE VALUES AROUND 2000 J/KG AND AMPLE LOW-LEVEL SHEAR AS WELL AS DEEP LAYER SHEAR SOUTH OF THIS BOUNDARY...SPC ISSUED A PDS TORNADO WATCH FOR MAINLY OUR SOUTHERN TWO TIERS OF COUNTIES UNTIL 9PM. ANYTHING CLOSEST TO THE HUNTSVILLE COUNTY WARNING AREA WILL HAVE THE BEST CHANCE SEEING A SIGNIFICANT THREAT FOR SUPERCELLS...WHICH MEANS A TORNADO...HAIL AND DAMAGING WIND THREAT. TORNADOES ON THE GROUND HAVE BEEN REPORTED IN NORTHERN MS ALREADY...MOVING NE. IT WILL BE A CLOSE CALL FOR FAR SOUTHERN MIDDLE TN. FYI...WE WILL ADD GRUNDY COUNTY TO THE WATCH AS WELL. ALSO...NORTH OF THIS BOUNDARY...SEVERE STORMS WILL STILL BE POSSIBLE BUT HAIL WILL BE THE ONLY SEVERE WEATHER THREAT FOR STORMS IN THE COLD POOL. SUPERCELLS OVER MS SHOULD COAGULATE INTO A LARGE AREA OF CONVECTION AND THIS SHOULD SPREAD NORTHWARD WITH TIME. OVERNIGHT...THIS WILL MOVE EAST THROUGH MIDDLE TN...AND POPS COULD TAPER FROM WEST TO EAST TOWARDS TUESDAY MORNING. AN ADDITIONAL 1-2 INCHES OF RAINFALL WILL BE POSSIBLE THROUGH TONIGHT...WITH LOWS AROUND 60. ON TUESDAY...THE SFC LOW SHOULD ROTATE A LITTLE FURTHER EAST AND ANOTHER LOBE OF ENERGY FROM THE UPPER LOW WILL SWING THROUGH THE REGION. WOULD THINK ANOTHER ROUND OF AFTERNOON-EVENING CONVECTION SHOULD EASILY BE GENERATED...THIS TIME WITH MORE SHEAR ACROSS MIDDLE TN...MORE SUNSHINE THROUGH THE MORNING HOURS...AND COLDER AIR ALOFT WITH THE UPPER LOW GETTING CLOSER. WOULD EXPECT ANOTHER ROUND OF SEVERE WEATHER TOMORROW AFTERNOON AND EVENING...WITH LARGE HAIL AND DAMAGING WINDS THE BEST THREAT. EVEN AN ISOLATED TORNADO OR TWO CAN NOT BE RULED OUT. FINALLY THE SYSTEM WILL MOSTLY PULL OUT ON WEDNESDAY...WITH PERHAPS SOME LINGERING SHOWERS INTO WEDNESDAY EVENING. TEMPS WILL COOL OFF INTO THE 70S ON WEDNESDAY...AND EVEN COOLER THURSDAY- SATURDAY IN THE 60S. CONDITIONS SHOULD MOSTLY BE DRY THURSDAY ON...WITH TEMPS WARMING BACK UP TO NEAR 80 SUNDAY AND MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
957 PM CDT MON APR 28 2014 .UPDATE... COVERAGE OVER THE MID STATE HAS DECREASED SOME AND IS MORE BROKEN IN NATURE NOW. INSTABILITY PARAMETERS CONTINUE TO LOOK RATHER WEAK ACROSS WESTERN MIDDLE ALTHOUGH 850 MB WIND IS STILL REASONABLY STRONG. STILL HOWEVER...THE BACK EDGE OF THE PRECIP HAS NOT MADE MUCH OF AN ADVANCEMENT EASTWARD YET. FURTHER EAST...CURRENTLY THE TOR WATCH AREA IS NOT UNDER AN IMMEDIATE THREAT. HOWEVER...WE DO SEE SOME STORM REDEVELOPMENT OVER NW AL AT THIS TIME AND HELICITY VALUES OVER THE WATCH AREA REMAIN ELEVATED. THEREFORE...WILL ELECT TO KEEP THE WATCH GOING FOR NOW. MAY BEGIN TO TAPER POPS ACROSS OUR WEST IN AN HOUR OR TWO...DEPENDING ON FUTURE TRENDS. OTW...NO CHANGES FOR NOW. && .PREV DISCUSSION... /ISSUED 816 PM CDT MON APR 28 2014/ AVIATION 00Z DISCUSSION... SEVERE WEATHER REMAINS A POSSIBILITY FOR THE CSV AREA. SHOWERS AND TSTMS WILL CONTINUE ACROSS MAINLY THE CSV AND BNA AREAS THROUGH AT LEAST 06Z. SOME OF THE STORMS COULD REACH STRONG OR SEVERE LIMITS NEAR CSV BETWEEN NOW AND 06Z. PRECIP SHOULD END BY 09Z FOR CSV WITH A BREAK UNTIL 18Z ON TUESDAY WHEN TSTMS MAY FIRE UP AGAIN. PREV DISCUSSION... /ISSUED 812 PM CDT MON APR 28 2014/ UPDATE... STRONG TO POTENTIALLY SEVERE TSTMS MARCHING NE ACROSS THE SOUTHERN PLATEAU. LAPS STILL SHOWING AN IMPRESSIVE SLUG OF AMPLIFIED HELICITY ACROSS THIS REGION. ALTHOUGH THE HELICITY STRENGTH IS ON THE DOWN SLIDE. TOR WATCH NUMBER 111 WILL BE ALLOWED TO CONTINUE FOR NOW FOR THOSE 6 COUNTIES IN OUR EAST AND SOUTHEAST. OTW...BACK EDGE OF THE SHOWER AND TSTM ACTIVITY EXTENDS FROM CLARKSVILLE SW THROUGH LOBELVILLE. NO EASTWARD PUSH IS INDICATED AND A SLIGHT WESTWARD PUSH IS INDICATED. MODELS STILL IN AGREEMENT WITH DRIER AIR WINNING OUT LATER TONIGHT. AT SOME POINT OVER THE NEXT FEW HOURS...SHOULD BEGIN TO SEE AN EASTWARD PUSH WITH THE PRECIP SLOWLY ENDING FROM WEST TO EAST. INSTABILITY PARAMETERS CONTINUE TO LOOK TOO WEAK TO SUPPORT SEVERE DEVELOPMENT. BUT...PERHAPS A STRONG STORM OR TWO COULD STILL DEVELOP OVER OUR SOUTHERN COUNTIES OVER THE NEXT HOUR OR TWO. FOR THE FORECAST...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 514 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... LATEST LAPS DATA CLEARLY SHOWS THAT THE BETTER INSTABILITY IS OVER OUR SOUTHERN AREAS WHICH IS WHERE THE TOR WATCH IS IN EFFECT. CAPE VALUES...SHOWALTERS ALL IN SUPPORT OF THE SUBSTANTIAL AMOUNTS OF INSTABILITY ACROSS THE SOUTH. CURRENT RADAR SHOWS THE STRONGEST ACTIVITY FROM DICKSON COUNTY SOUTHWARD THROUGH GILES COUNTY WITH AGAIN...THE STRONGEST ACTIVITY THE FURTHER SOUTH YOU GO. WE DO SEE A LINE OF THUNDERSTORMS ATTEMPTING TO DEVELOP BACK ACROSS WESTERN KY. HOWEVER...THERE IS A DEGREE OF INCREASING CAP STRENGTH ACROSS OUR NORTHERN AREAS. THUS...IT MAY HAVE A TOUGH TIME DEVELOPING INTO SOMETHING MORE SUBSTANTIAL. HRRR FURTHER CONCURS WITH THE IDEA OF NO REDEVELOPMENT TONIGHT TO THE WEST OF THE AFOREMENTIONED STRONGEST CONVECTION. BIGGEST POTENTIAL IMPACT OVER THE NEXT FEW HOURS WILL BE OVER OUR SOUTHERN AREAS WHERE THE POTENTIALLY TORNADIC CELLS COULD CLIP OUR FAR SOUTHERN COUNTIES AND EVENTUALLY OUR SOUTHERN PLATEAU. AS FOR THE FLOOD THREAT...THE FLASH FLOOD WATCH CONTINUES THROUGH TUESDAY EVENING. PREV DISCUSSION... /ISSUED 256 PM CDT MON APR 28 2014/ DISCUSSION... SIGNIFICANT SEVERE WEATHER THREAT STILL EXISTS OVER FAR SOUTHERN MIDDLE TN THROUGH TONIGHT... A STRONG LOW PRESSURE CENTER OVER EASTERN NEBRASKA WILL DRAG A COLD FRONT THROUGH THE REGION LATE TONIGHT...WITH ITS UPPER LOW LAGGING AND SPINNING ACROSS THE UPPER MIDWEST. STRONG DIVERGENCE ALOFT ON THE NOSE OF A 115-KT UPPER JET HAS LED TO AMPLE PRECIP ACROSS MIDDLE TN THIS MORNING THROUGH THE EARLY AFTERNOON HOURS. THIS ACTIVITY HAS LED TO 3-5 INCH RAINFALL AMOUNTS MAINLY WEST OF I-65 AND SOUTH OF I-40...WHERE RESIDUAL FLOODING AND FLASH FLOODING CONTINUE. A FLASH FLOOD WATCH CONTINUES FOR ALL OF MIDDLE TN AND WILL BE EXTENDED THROUGH TUESDAY AFTERNOON GIVEN THE RIVER FLOODING THREAT FROM ADDITIONAL RAINS FROM THIS EVENING THROUGH THE OVERNIGHT HOURS. WILL ISSUE THE UPDATED FLASH FLOOD WATCH SOON. MORE INTERESTINGLY...THE MORNING CONVECTION DROPPED AN OUTFLOW BOUNDARY ACROSS FAR SOUTHERN MIDDLE TN...WHERE POINTS NORTH OF THAT BOUNDARY REMAIN IN THE COLD POOL REGION...AND POINTS ALONG AND SOUTH OF THIS BOUNDARY REMAIN VERY UNSTABLE. THIS BOUNDARY EVEN CURLS BACK TO THE WEST A BIT OVER OUR FAR EASTERN CWA. WITH SFC CAPE VALUES AROUND 2000 J/KG AND AMPLE LOW-LEVEL SHEAR AS WELL AS DEEP LAYER SHEAR SOUTH OF THIS BOUNDARY...SPC ISSUED A PDS TORNADO WATCH FOR MAINLY OUR SOUTHERN TWO TIERS OF COUNTIES UNTIL 9PM. ANYTHING CLOSEST TO THE HUNTSVILLE COUNTY WARNING AREA WILL HAVE THE BEST CHANCE SEEING A SIGNIFICANT THREAT FOR SUPERCELLS...WHICH MEANS A TORNADO...HAIL AND DAMAGING WIND THREAT. TORNADOES ON THE GROUND HAVE BEEN REPORTED IN NORTHERN MS ALREADY...MOVING NE. IT WILL BE A CLOSE CALL FOR FAR SOUTHERN MIDDLE TN. FYI...WE WILL ADD GRUNDY COUNTY TO THE WATCH AS WELL. ALSO...NORTH OF THIS BOUNDARY...SEVERE STORMS WILL STILL BE POSSIBLE BUT HAIL WILL BE THE ONLY SEVERE WEATHER THREAT FOR STORMS IN THE COLD POOL. SUPERCELLS OVER MS SHOULD COAGULATE INTO A LARGE AREA OF CONVECTION AND THIS SHOULD SPREAD NORTHWARD WITH TIME. OVERNIGHT...THIS WILL MOVE EAST THROUGH MIDDLE TN...AND POPS COULD TAPER FROM WEST TO EAST TOWARDS TUESDAY MORNING. AN ADDITIONAL 1-2 INCHES OF RAINFALL WILL BE POSSIBLE THROUGH TONIGHT...WITH LOWS AROUND 60. ON TUESDAY...THE SFC LOW SHOULD ROTATE A LITTLE FURTHER EAST AND ANOTHER LOBE OF ENERGY FROM THE UPPER LOW WILL SWING THROUGH THE REGION. WOULD THINK ANOTHER ROUND OF AFTERNOON-EVENING CONVECTION SHOULD EASILY BE GENERATED...THIS TIME WITH MORE SHEAR ACROSS MIDDLE TN...MORE SUNSHINE THROUGH THE MORNING HOURS...AND COLDER AIR ALOFT WITH THE UPPER LOW GETTING CLOSER. WOULD EXPECT ANOTHER ROUND OF SEVERE WEATHER TOMORROW AFTERNOON AND EVENING...WITH LARGE HAIL AND DAMAGING WINDS THE BEST THREAT. EVEN AN ISOLATED TORNADO OR TWO CAN NOT BE RULED OUT. FINALLY THE SYSTEM WILL MOSTLY PULL OUT ON WEDNESDAY...WITH PERHAPS SOME LINGERING SHOWERS INTO WEDNESDAY EVENING. TEMPS WILL COOL OFF INTO THE 70S ON WEDNESDAY...AND EVEN COOLER THURSDAY- SATURDAY IN THE 60S. CONDITIONS SHOULD MOSTLY BE DRY THURSDAY ON...WITH TEMPS WARMING BACK UP TO NEAR 80 SUNDAY AND MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
816 PM CDT MON APR 28 2014 .AVIATION 00Z DISCUSSION... SEVERE WEATHER REMAINS A POSSIBILITY FOR THE CSV AREA. SHOWERS AND TSTMS WILL CONTINUE ACROSS MAINLY THE CSV AND BNA AREAS THROUGH AT LEAST 06Z. SOME OF THE STORMS COULD REACH STRONG OR SEVERE LIMITS NEAR CSV BETWEEN NOW AND 06Z. PRECIP SHOULD END BY 09Z FOR CSV WITH A BREAK UNTIL 18Z ON TUESDAY WHEN TSTMS MAY FIRE UP AGAIN. && .PREV DISCUSSION... /ISSUED 812 PM CDT MON APR 28 2014/ UPDATE... STRONG TO POTENTIALLY SEVERE TSTMS MARCHING NE ACROSS THE SOUTHERN PLATEAU. LAPS STILL SHOWING AN IMPRESSIVE SLUG OF AMPLIFIED HELICITY ACROSS THIS REGION. ALTHOUGH THE HELICITY STRENGTH IS ON THE DOWN SLIDE. TOR WATCH NUMBER 111 WILL BE ALLOWED TO CONTINUE FOR NOW FOR THOSE 6 COUNTIES IN OUR EAST AND SOUTHEAST. OTW...BACK EDGE OF THE SHOWER AND TSTM ACTIVITY EXTENDS FROM CLARKSVILLE SW THROUGH LOBELVILLE. NO EASTWARD PUSH IS INDICATED AND A SLIGHT WESTWARD PUSH IS INDICATED. MODELS STILL IN AGREEMENT WITH DRIER AIR WINNING OUT LATER TONIGHT. AT SOME POINT OVER THE NEXT FEW HOURS...SHOULD BEGIN TO SEE AN EASTWARD PUSH WITH THE PRECIP SLOWLY ENDING FROM WEST TO EAST. INSTABILITY PARAMETERS CONTINUE TO LOOK TOO WEAK TO SUPPORT SEVERE DEVELOPMENT. BUT...PERHAPS A STRONG STORM OR TWO COULD STILL DEVELOP OVER OUR SOUTHERN COUNTIES OVER THE NEXT HOUR OR TWO. FOR THE FORECAST...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 514 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... LATEST LAPS DATA CLEARLY SHOWS THAT THE BETTER INSTABILITY IS OVER OUR SOUTHERN AREAS WHICH IS WHERE THE TOR WATCH IS IN EFFECT. CAPE VALUES...SHOWALTERS ALL IN SUPPORT OF THE SUBSTANTIAL AMOUNTS OF INSTABILITY ACROSS THE SOUTH. CURRENT RADAR SHOWS THE STRONGEST ACTIVITY FROM DICKSON COUNTY SOUTHWARD THROUGH GILES COUNTY WITH AGAIN...THE STRONGEST ACTIVITY THE FURTHER SOUTH YOU GO. WE DO SEE A LINE OF THUNDERSTORMS ATTEMPTING TO DEVELOP BACK ACROSS WESTERN KY. HOWEVER...THERE IS A DEGREE OF INCREASING CAP STRENGTH ACROSS OUR NORTHERN AREAS. THUS...IT MAY HAVE A TOUGH TIME DEVELOPING INTO SOMETHING MORE SUBSTANTIAL. HRRR FURTHER CONCURS WITH THE IDEA OF NO REDEVELOPMENT TONIGHT TO THE WEST OF THE AFOREMENTIONED STRONGEST CONVECTION. BIGGEST POTENTIAL IMPACT OVER THE NEXT FEW HOURS WILL BE OVER OUR SOUTHERN AREAS WHERE THE POTENTIALLY TORNADIC CELLS COULD CLIP OUR FAR SOUTHERN COUNTIES AND EVENTUALLY OUR SOUTHERN PLATEAU. AS FOR THE FLOOD THREAT...THE FLASH FLOOD WATCH CONTINUES THROUGH TUESDAY EVENING. PREV DISCUSSION... /ISSUED 256 PM CDT MON APR 28 2014/ DISCUSSION... SIGNIFICANT SEVERE WEATHER THREAT STILL EXISTS OVER FAR SOUTHERN MIDDLE TN THROUGH TONIGHT... A STRONG LOW PRESSURE CENTER OVER EASTERN NEBRASKA WILL DRAG A COLD FRONT THROUGH THE REGION LATE TONIGHT...WITH ITS UPPER LOW LAGGING AND SPINNING ACROSS THE UPPER MIDWEST. STRONG DIVERGENCE ALOFT ON THE NOSE OF A 115-KT UPPER JET HAS LED TO AMPLE PRECIP ACROSS MIDDLE TN THIS MORNING THROUGH THE EARLY AFTERNOON HOURS. THIS ACTIVITY HAS LED TO 3-5 INCH RAINFALL AMOUNTS MAINLY WEST OF I-65 AND SOUTH OF I-40...WHERE RESIDUAL FLOODING AND FLASH FLOODING CONTINUE. A FLASH FLOOD WATCH CONTINUES FOR ALL OF MIDDLE TN AND WILL BE EXTENDED THROUGH TUESDAY AFTERNOON GIVEN THE RIVER FLOODING THREAT FROM ADDITIONAL RAINS FROM THIS EVENING THROUGH THE OVERNIGHT HOURS. WILL ISSUE THE UPDATED FLASH FLOOD WATCH SOON. MORE INTERESTINGLY...THE MORNING CONVECTION DROPPED AN OUTFLOW BOUNDARY ACROSS FAR SOUTHERN MIDDLE TN...WHERE POINTS NORTH OF THAT BOUNDARY REMAIN IN THE COLD POOL REGION...AND POINTS ALONG AND SOUTH OF THIS BOUNDARY REMAIN VERY UNSTABLE. THIS BOUNDARY EVEN CURLS BACK TO THE WEST A BIT OVER OUR FAR EASTERN CWA. WITH SFC CAPE VALUES AROUND 2000 J/KG AND AMPLE LOW-LEVEL SHEAR AS WELL AS DEEP LAYER SHEAR SOUTH OF THIS BOUNDARY...SPC ISSUED A PDS TORNADO WATCH FOR MAINLY OUR SOUTHERN TWO TIERS OF COUNTIES UNTIL 9PM. ANYTHING CLOSEST TO THE HUNTSVILLE COUNTY WARNING AREA WILL HAVE THE BEST CHANCE SEEING A SIGNIFICANT THREAT FOR SUPERCELLS...WHICH MEANS A TORNADO...HAIL AND DAMAGING WIND THREAT. TORNADOES ON THE GROUND HAVE BEEN REPORTED IN NORTHERN MS ALREADY...MOVING NE. IT WILL BE A CLOSE CALL FOR FAR SOUTHERN MIDDLE TN. FYI...WE WILL ADD GRUNDY COUNTY TO THE WATCH AS WELL. ALSO...NORTH OF THIS BOUNDARY...SEVERE STORMS WILL STILL BE POSSIBLE BUT HAIL WILL BE THE ONLY SEVERE WEATHER THREAT FOR STORMS IN THE COLD POOL. SUPERCELLS OVER MS SHOULD COAGULATE INTO A LARGE AREA OF CONVECTION AND THIS SHOULD SPREAD NORTHWARD WITH TIME. OVERNIGHT...THIS WILL MOVE EAST THROUGH MIDDLE TN...AND POPS COULD TAPER FROM WEST TO EAST TOWARDS TUESDAY MORNING. AN ADDITIONAL 1-2 INCHES OF RAINFALL WILL BE POSSIBLE THROUGH TONIGHT...WITH LOWS AROUND 60. ON TUESDAY...THE SFC LOW SHOULD ROTATE A LITTLE FURTHER EAST AND ANOTHER LOBE OF ENERGY FROM THE UPPER LOW WILL SWING THROUGH THE REGION. WOULD THINK ANOTHER ROUND OF AFTERNOON-EVENING CONVECTION SHOULD EASILY BE GENERATED...THIS TIME WITH MORE SHEAR ACROSS MIDDLE TN...MORE SUNSHINE THROUGH THE MORNING HOURS...AND COLDER AIR ALOFT WITH THE UPPER LOW GETTING CLOSER. WOULD EXPECT ANOTHER ROUND OF SEVERE WEATHER TOMORROW AFTERNOON AND EVENING...WITH LARGE HAIL AND DAMAGING WINDS THE BEST THREAT. EVEN AN ISOLATED TORNADO OR TWO CAN NOT BE RULED OUT. FINALLY THE SYSTEM WILL MOSTLY PULL OUT ON WEDNESDAY...WITH PERHAPS SOME LINGERING SHOWERS INTO WEDNESDAY EVENING. TEMPS WILL COOL OFF INTO THE 70S ON WEDNESDAY...AND EVEN COOLER THURSDAY- SATURDAY IN THE 60S. CONDITIONS SHOULD MOSTLY BE DRY THURSDAY ON...WITH TEMPS WARMING BACK UP TO NEAR 80 SUNDAY AND MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
812 PM CDT MON APR 28 2014 .UPDATE... STRONG TO POTENTIALLY SEVERE TSTMS MARCHING NE ACROSS THE SOUTHERN PLATEAU. LAPS STILL SHOWING AN IMPRESSIVE SLUG OF AMPLIFIED HELICITY ACROSS THIS REGION. ALTHOUGH THE HELICITY STRENGTH IS ON THE DOWN SLIDE. TOR WATCH NUMBER 111 WILL BE ALLOWED TO CONTINUE FOR NOW FOR THOSE 6 COUNTIES IN OUR EAST AND SOUTHEAST. OTW...BACK EDGE OF THE SHOWER AND TSTM ACTIVITY EXTENDS FROM CLARKSVILLE SW THROUGH LOBELVILLE. NO EASTWARD PUSH IS INDICATED AND A SLIGHT WESTWARD PUSH IS INDICATED. MODELS STILL IN AGREEMENT WITH DRIER AIR WINNING OUT LATER TONIGHT. AT SOME POINT OVER THE NEXT FEW HOURS...SHOULD BEGIN TO SEE AN EASTWARD PUSH WITH THE PRECIP SLOWLY ENDING FROM WEST TO EAST. INSTABILITY PARAMETERS CONTINUE TO LOOK TOO WEAK TO SUPPORT SEVERE DEVELOPMENT. BUT...PERHAPS A STRONG STORM OR TWO COULD STILL DEVELOP OVER OUR SOUTHERN COUNTIES OVER THE NEXT HOUR OR TWO. FOR THE FORECAST...NO CHANGES FOR NOW. && .PREV DISCUSSION... /ISSUED 514 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... LATEST LAPS DATA CLEARLY SHOWS THAT THE BETTER INSTABILITY IS OVER OUR SOUTHERN AREAS WHICH IS WHERE THE TOR WATCH IS IN EFFECT. CAPE VALUES...SHOWALTERS ALL IN SUPPORT OF THE SUBSTANTIAL AMOUNTS OF INSTABILITY ACROSS THE SOUTH. CURRENT RADAR SHOWS THE STRONGEST ACTIVITY FROM DICKSON COUNTY SOUTHWARD THROUGH GILES COUNTY WITH AGAIN...THE STRONGEST ACTIVITY THE FURTHER SOUTH YOU GO. WE DO SEE A LINE OF THUNDERSTORMS ATTEMPTING TO DEVELOP BACK ACROSS WESTERN KY. HOWEVER...THERE IS A DEGREE OF INCREASING CAP STRENGTH ACROSS OUR NORTHERN AREAS. THUS...IT MAY HAVE A TOUGH TIME DEVELOPING INTO SOMETHING MORE SUBSTANTIAL. HRRR FURTHER CONCURS WITH THE IDEA OF NO REDEVELOPMENT TONIGHT TO THE WEST OF THE AFOREMENTIONED STRONGEST CONVECTION. BIGGEST POTENTIAL IMPACT OVER THE NEXT FEW HOURS WILL BE OVER OUR SOUTHERN AREAS WHERE THE POTENTIALLY TORNADIC CELLS COULD CLIP OUR FAR SOUTHERN COUNTIES AND EVENTUALLY OUR SOUTHERN PLATEAU. AS FOR THE FLOOD THREAT...THE FLASH FLOOD WATCH CONTINUES THROUGH TUESDAY EVENING. PREV DISCUSSION... /ISSUED 256 PM CDT MON APR 28 2014/ DISCUSSION... .SIGNIFICANT SEVERE WEATHER THREAT STILL EXISTS OVER FAR SOUTHERN MIDDLE TN THROUGH TONIGHT... A STRONG LOW PRESSURE CENTER OVER EASTERN NEBRASKA WILL DRAG A COLD FRONT THROUGH THE REGION LATE TONIGHT...WITH ITS UPPER LOW LAGGING AND SPINNING ACROSS THE UPPER MIDWEST. STRONG DIVERGENCE ALOFT ON THE NOSE OF A 115-KT UPPER JET HAS LED TO AMPLE PRECIP ACROSS MIDDLE TN THIS MORNING THROUGH THE EARLY AFTERNOON HOURS. THIS ACTIVITY HAS LED TO 3-5 INCH RAINFALL AMOUNTS MAINLY WEST OF I-65 AND SOUTH OF I-40...WHERE RESIDUAL FLOODING AND FLASH FLOODING CONTINUE. A FLASH FLOOD WATCH CONTINUES FOR ALL OF MIDDLE TN AND WILL BE EXTENDED THROUGH TUESDAY AFTERNOON GIVEN THE RIVER FLOODING THREAT FROM ADDITIONAL RAINS FROM THIS EVENING THROUGH THE OVERNIGHT HOURS. WILL ISSUE THE UPDATED FLASH FLOOD WATCH SOON. MORE INTERESTINGLY...THE MORNING CONVECTION DROPPED AN OUTFLOW BOUNDARY ACROSS FAR SOUTHERN MIDDLE TN...WHERE POINTS NORTH OF THAT BOUNDARY REMAIN IN THE COLD POOL REGION...AND POINTS ALONG AND SOUTH OF THIS BOUNDARY REMAIN VERY UNSTABLE. THIS BOUNDARY EVEN CURLS BACK TO THE WEST A BIT OVER OUR FAR EASTERN CWA. WITH SFC CAPE VALUES AROUND 2000 J/KG AND AMPLE LOW-LEVEL SHEAR AS WELL AS DEEP LAYER SHEAR SOUTH OF THIS BOUNDARY...SPC ISSUED A PDS TORNADO WATCH FOR MAINLY OUR SOUTHERN TWO TIERS OF COUNTIES UNTIL 9PM. ANYTHING CLOSEST TO THE HUNTSVILLE COUNTY WARNING AREA WILL HAVE THE BEST CHANCE SEEING A SIGNIFICANT THREAT FOR SUPERCELLS...WHICH MEANS A TORNADO...HAIL AND DAMAGING WIND THREAT. TORNADOES ON THE GROUND HAVE BEEN REPORTED IN NORTHERN MS ALREADY...MOVING NE. IT WILL BE A CLOSE CALL FOR FAR SOUTHERN MIDDLE TN. FYI...WE WILL ADD GRUNDY COUNTY TO THE WATCH AS WELL. ALSO...NORTH OF THIS BOUNDARY...SEVERE STORMS WILL STILL BE POSSIBLE BUT HAIL WILL BE THE ONLY SEVERE WEATHER THREAT FOR STORMS IN THE COLD POOL. SUPERCELLS OVER MS SHOULD COAGULATE INTO A LARGE AREA OF CONVECTION AND THIS SHOULD SPREAD NORTHWARD WITH TIME. OVERNIGHT...THIS WILL MOVE EAST THROUGH MIDDLE TN...AND POPS COULD TAPER FROM WEST TO EAST TOWARDS TUESDAY MORNING. AN ADDITIONAL 1-2 INCHES OF RAINFALL WILL BE POSSIBLE THROUGH TONIGHT...WITH LOWS AROUND 60. ON TUESDAY...THE SFC LOW SHOULD ROTATE A LITTLE FURTHER EAST AND ANOTHER LOBE OF ENERGY FROM THE UPPER LOW WILL SWING THROUGH THE REGION. WOULD THINK ANOTHER ROUND OF AFTERNOON-EVENING CONVECTION SHOULD EASILY BE GENERATED...THIS TIME WITH MORE SHEAR ACROSS MIDDLE TN...MORE SUNSHINE THROUGH THE MORNING HOURS...AND COLDER AIR ALOFT WITH THE UPPER LOW GETTING CLOSER. WOULD EXPECT ANOTHER ROUND OF SEVERE WEATHER TOMORROW AFTERNOON AND EVENING...WITH LARGE HAIL AND DAMAGING WINDS THE BEST THREAT. EVEN AN ISOLATED TORNADO OR TWO CAN NOT BE RULED OUT. FINALLY THE SYSTEM WILL MOSTLY PULL OUT ON WEDNESDAY...WITH PERHAPS SOME LINGERING SHOWERS INTO WEDNESDAY EVENING. TEMPS WILL COOL OFF INTO THE 70S ON WEDNESDAY...AND EVEN COOLER THURSDAY- SATURDAY IN THE 60S. CONDITIONS SHOULD MOSTLY BE DRY THURSDAY ON...WITH TEMPS WARMING BACK UP TO NEAR 80 SUNDAY AND MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ 21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
127 PM CDT SUN APR 27 2014 .DISCUSSION... UPDATED FOR 18Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1057 AM CDT SUN APR 27 2014/ UPDATE... CONVECTION CONTINUES ACROSS MUCH OF THE MIDSOUTH. THE ACTIVITY IS AHEAD OF A SECONDARY WARM FRONT. MODELS INDICATE THAT THE FRONT AND CONVECTION WILL SLOWLY LIFT TO THE NORTHEAST AS THE DAY PROGRESSES. BEHIND THE FRONT...THE ATMOSPHERE BECOMES EVEN MORE UNSTABLE. DEWPOINTS WILL CLIMB INTO THE UPPER 60S AS TEMPERATURES RISE INTO THE LOWER 80S. A FEW SUPERCELLS MAY DEVELOP ACROSS SOUTHERN ARKANSAS DURING THE AFTERNOON AND EARLY EVENING HOURS AHEAD OF THE THUNDERSTORM ACTIVITY THAT DEVELOPS ALONG THE DRY LINE WHICH IS CURRENTLY OVER EASTERN OKLAHOMA. THESE SUPERCELLS MAY PUSH INTO EASTERN ARKANSAS DURING THE LATE AFTERNOON TO EARLY EVENING HOURS. MEANWHILE...DRY LINE THUNDERSTORM ACTIVITY WILL LIKELY MOVE INTO THE MIDSOUTH AFTER 8 PM. HAVE ADJUSTED POPS ACCORDINGLY. UPDATE WILL BE OUT SHORTLY. KRM DISCUSSION... /ISSUED 455 AM CDT SUN APR 27 2014/ DANGEROUS SEVERE WEATHER OUTBREAK INCLUDING STRONG TORNADOES EXPECTED ACROSS PORTIONS OF THE MIDSOUTH FROM LATE THIS AFTERNOON INTO TONIGHT. ANOTHER SEVERE WEATHER OUTBREAK IS POSSIBLE MONDAY AND AGAIN TUESDAY FOR PORTIONS OF THE AREA. THE CALM BEFORE THE STORM WAS OBSERVED ACROSS THE MIDSOUTH EARLY THIS MORNING. SKIES WERE MOSTLY CLOUDY WITH A LIGHT SOUTHEAST WIND. TEMPERATURES WERE WARMER THAN THE LAST COUPLE OF MORNINGS WITH READINGS AT 4 AM RANGING FROM 59 DEGREES AT PARIS TN TO 72 DEGREES AT CLARKSDALE MS. A WARM FRONT WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST AND WILL MOVE THROUGH THE REGION THIS MORNING. THE ATMOSPHERE WAS MORE MOIST AND UNSTABLE SOUTHWEST OF THE WARM FRONT WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 60S. A FEW THUNDERSTORMS WERE BEGINNING TO BREAK OUT OVER SOUTHEAST AR. THE LATEST HIGH RESOLUTION RAPID REFRESH MODEL (HRRR) INDICATES SHOWERS AND THUNDERSTORMS INCREASING ALONG THE FRONT THIS MORNING AS IT MOVES INTO THE MIDSOUTH. AN UPPER LEVEL SHORT WAVE WILL ALSO HELP TO TRIGGER SHOWERS AND THUNDERSTORMS. ADJUSTED AND INCREASED THE POPS FOR THIS MORNING BASED ON THE LATEST HRRR MODEL. ATTENTION THEN TURNS TO A MUCH MORE SERIOUS SEVERE WEATHER AND FLASH FLOOD SETUP THAT WILL DEVELOP ACROSS THE MIDSOUTH BEGINNING BY LATE AFTERNOON. AS THE WARM FRONT MOVES TO THE NORTHEAST...VERY UNSTABLE AND MOIST AIR WILL PUSH INTO THE MIDSOUTH. A STRONG AND CLOSED UPPER LEVEL LOW WILL MOVE INTO WESTERN NE AND WESTERN KS. AN ASSOCIATED DRY LINE WILL EXTEND AT EARLY EVENING FROM EASTERN KS INTO EASTERN OK. PARAMETERS ARE COMING TOGETHER FOR THE FORMATION OF DISCRETE SUPERCELLS TO DEVELOP ACROSS THE ARKLATEX REGION INTO CENTRAL AR THIS AFTERNOON...THEN SPREAD INTO EASTERN AR AND PORTIONS OF NORTHWEST MS BY LATE AFTERNOON OR EARLY EVENING...THEN CROSSING INTO WEST TN ALONG THE MS RIVER THIS EVENING. SEVERE WEATHER PARAMETERS ARE IMPRESSIVE FOR THE POSSIBILITY OF SIGNIFICANT TORNADOES. MIXED LAYER MOST UNSTABLE CAPE WILL INCREASE TO BETWEEN 2000 AND 3000 J/KG WITH 0-1 KM STORM RELATIVE HELICITY INCREASING TO BETWEEN 300 AND 350 M2/S2. 850 WINDS INCREASE TO 50 KTS. A MODERATE RISK OF SEVERE THUNDERSTORMS EXIST ACROSS ALL OF EAST ARKANSAS...THE MISSOURI BOOTHEEL AND THOSE PORTIONS OF WEST TENNESSEE AND NORTH MISSISSIPPI ALONG AND WEST OF A LINE FROM DYERSBURG TENNESSEE TO CHARLESTON MISSISSIPPI. A SLIGHT RISK OF SEVERE THUNDERSTORMS EXIST ELSEWHERE ACROSS THE MIDSOUTH FOR TONIGHT. A FEW TORNADOES...DAMAGING WINDS...AND LARGE HAIL ARE LIKELY. TORNADOES MAY BE STRONG ESPECIALLY IN THE MODERATE RISK AREA. THINK TONIGHT WILL BE A VERY ACTIVE NIGHT WEATHERWISE AS THUNDERSTORMS CONTINUE TO PUSH EASTWARD AND CONGEAL INTO ONE OR MORE MESOSCALE CONVECTIVE SYSTEMS. ALTHOUGH...DISCRETE SUPERCELLS MAY ALSO CONTINUE WELL INTO THE NIGHT. THE DRY LINE WILL PUSH INTO WESTERN MO AND WESTERN AR OVERNIGHT. HEAVY RAINFALL AND FLASH FLOODING WILL BE ON THE INCREASE WITH PRECIPITABLE WATER VALUES CLIMBING TO BETWEEN 1.5 AND 1.9 INCHES. ISSUED A WIND ADVISORY FOR STRONG AND GUSTY SOUTHERLY GRADIENT WINDS FOR EAST ARKANSAS...AND PORTIONS OF THE MISSOURI BOOTHEEL AND NORTHWEST MISSISSIPPI FROM LATE THIS MORNING INTO THIS EVENING. ON MONDAY...CONDITIONS MAY SETTLE DOWN BRIEFING LATE TONIGHT AND EARLY MONDAY MORNING WITH INSTABILITY TEMPORARILY WANING. BUT WITH STRONG UPPER LEVEL DYNAMICS AND HIGH SHEAR CONTINUING ALONG WITH SOME INSTABILITY...SOME THUNDERSTORMS STILL MAY POSE A THREAT OF BECOMING SEVERE EVEN EARLY IN THE MORNING. HOWEVER...THE MAIN THREAT OF ANOTHER SEVERE WEATHER OUTBREAK WILL OCCUR MONDAY AFTERNOON INTO MONDAY NIGHT SHIFTING TO EAST OF THE MS RIVER ACROSS MUCH OF NORTH MS INTO PORTIONS OF WEST TN. A FEW STRONG TORNADOES...DAMAGING WINDS...LARGE HAIL...AND HEAVY RAINFALL ARE ALL LIKELY ONCE AGAIN. THE DRY LINE WILL MOVE INTO EASTERN AR BY SUNSET MONDAY AS THE STRONG UPPER LOW OVER THE CENTRAL PLAINS MOVES EASTWARD. THE SITUATION BECOMES SOMEWHAT MUDDLED BY TUESDAY WITH ALL THE PREVIOUS CONVECTION AND THE MODELS NOT IN THE BEST AGREEMENT ON EXACTLY HOW FAST THE DRY LINE / COLD FRONT PUSHES TO THE EAST. RIGHT NOW...IT LOOKS LIKE THE BEST CHANCE FOR ORGANIZED SEVERE WEATHER WILL SHIFT TO NORTHEAST MS. DRY AND COOLER WEATHER WILL RETURN WEDNESDAY CONTINUING INTO THE BEGINNING OF NEXT WEEKEND. JCL && .AVIATION... 18Z TAF CYCLE CONVECTION ASSOCIATED WITH WARM FRONT LIFTING VERY SLOWLY NORTH TODAY. AS A RESULT EXPECT TSRAS THROUGH MOST OF THE AFTERNOON AT KMKL...KJBR AND KMEM WITH MVFR OCNL IFR CONDS. AS THE FRONT AND TSRAS LIFT NORTH VFR CONDS WILL RETURN TEMPORARILY BEFORE THE NEXT LINE OF SHRAS AND TSRAS PUSH IN AHEAD OF THE APPROACHING DRY LINE PUSH IN THIS EVENING AND OVERNIGHT...ALONG WITH MVFR OCNL IFR CONDS. BY LATER TONIGHT AND EARLY MON EXPECT THE MAIN AREA OF SHRAS AND TSRAS TO SHIFT EAST WITH MVFR/IFR CIGS LINGERING. TSRAS MAY START REDEVELOPING BY MID MORNING ON MON SO INCLUDED A VCTS TO INDICATE THAT POSSIBILITY. SE WINDS WILL BE LIGHTER THAN EXPECTED THIS AFTERNOON...EVENTUALLY SHIFTING TO THE SOUTH AND INCREASING THIS EVENING TO 15 KTS WITH HIGHER GUSTS...AND SSW BY MON MORNING. SJM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD- CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI- PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD- CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI- PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR DUNKLIN. FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR ALCORN-BENTON MS- CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS- MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN- TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA. TN...FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR BENTON TN-CARROLL- CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN- HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON- MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1057 AM CDT SUN APR 27 2014 .UPDATE... CONVECTION CONTINUES ACROSS MUCH OF THE MIDSOUTH. THE ACTIVITY IS AHEAD OF A SECONDARY WARM FRONT. MODELS INDICATE THAT THE FRONT AND CONVECTION WILL SLOWLY LIFT TO THE NORTHEAST AS THE DAY PROGRESSES. BEHIND THE FRONT...THE ATMOSPHERE BECOMES EVEN MORE UNSTABLE. DEWPOINTS WILL CLIMB INTO THE UPPER 60S AS TEMPERATURES RISE INTO THE LOWER 80S. A FEW SUPERCELLS MAY DEVELOP ACROSS SOUTHERN ARKANSAS DURING THE AFTERNOON AND EARLY EVENING HOURS AHEAD OF THE THUNDERSTORM ACTIVITY THAT DEVELOPS ALONG THE DRY LINE WHICH IS CURRENTLY OVER EASTERN OKLAHOMA. THESE SUPERCELLS MAY PUSH INTO EASTERN ARKANSAS DURING THE LATE AFTERNOON TO EARLY EVENING HOURS. MEANWHILE...DRY LINE THUNDERSTORM ACTIVITY WILL LIKELY MOVE INTO THE MIDSOUTH AFTER 8 PM. HAVE ADJUSTED POPS ACCORDINGLY. UPDATE WILL BE OUT SHORTLY. KRM && .DISCUSSION... /ISSUED 455 AM CDT SUN APR 27 2014/ DANGEROUS SEVERE WEATHER OUTBREAK INCLUDING STRONG TORNADOES EXPECTED ACROSS PORTIONS OF THE MIDSOUTH FROM LATE THIS AFTERNOON INTO TONIGHT. ANOTHER SEVERE WEATHER OUTBREAK IS POSSIBLE MONDAY AND AGAIN TUESDAY FOR PORTIONS OF THE AREA. THE CALM BEFORE THE STORM WAS OBSERVED ACROSS THE MIDSOUTH EARLY THIS MORNING. SKIES WERE MOSTLY CLOUDY WITH A LIGHT SOUTHEAST WIND. TEMPERATURES WERE WARMER THAN THE LAST COUPLE OF MORNINGS WITH READINGS AT 4 AM RANGING FROM 59 DEGREES AT PARIS TN TO 72 DEGREES AT CLARKSDALE MS. A WARM FRONT WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST AND WILL MOVE THROUGH THE REGION THIS MORNING. THE ATMOSPHERE WAS MORE MOIST AND UNSTABLE SOUTHWEST OF THE WARM FRONT WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 60S. A FEW THUNDERSTORMS WERE BEGINNING TO BREAK OUT OVER SOUTHEAST AR. THE LATEST HIGH RESOLUTION RAPID REFRESH MODEL (HRRR) INDICATES SHOWERS AND THUNDERSTORMS INCREASING ALONG THE FRONT THIS MORNING AS IT MOVES INTO THE MIDSOUTH. AN UPPER LEVEL SHORT WAVE WILL ALSO HELP TO TRIGGER SHOWERS AND THUNDERSTORMS. ADJUSTED AND INCREASED THE POPS FOR THIS MORNING BASED ON THE LATEST HRRR MODEL. ATTENTION THEN TURNS TO A MUCH MORE SERIOUS SEVERE WEATHER AND FLASH FLOOD SETUP THAT WILL DEVELOP ACROSS THE MIDSOUTH BEGINNING BY LATE AFTERNOON. AS THE WARM FRONT MOVES TO THE NORTHEAST...VERY UNSTABLE AND MOIST AIR WILL PUSH INTO THE MIDSOUTH. A STRONG AND CLOSED UPPER LEVEL LOW WILL MOVE INTO WESTERN NE AND WESTERN KS. AN ASSOCIATED DRY LINE WILL EXTEND AT EARLY EVENING FROM EASTERN KS INTO EASTERN OK. PARAMETERS ARE COMING TOGETHER FOR THE FORMATION OF DISCRETE SUPERCELLS TO DEVELOP ACROSS THE ARKLATEX REGION INTO CENTRAL AR THIS AFTERNOON...THEN SPREAD INTO EASTERN AR AND PORTIONS OF NORTHWEST MS BY LATE AFTERNOON OR EARLY EVENING...THEN CROSSING INTO WEST TN ALONG THE MS RIVER THIS EVENING. SEVERE WEATHER PARAMETERS ARE IMPRESSIVE FOR THE POSSIBILITY OF SIGNIFICANT TORNADOES. MIXED LAYER MOST UNSTABLE CAPE WILL INCREASE TO BETWEEN 2000 AND 3000 J/KG WITH 0-1 KM STORM RELATIVE HELICITY INCREASING TO BETWEEN 300 AND 350 M2/S2. 850 WINDS INCREASE TO 50 KTS. A MODERATE RISK OF SEVERE THUNDERSTORMS EXIST ACROSS ALL OF EAST ARKANSAS...THE MISSOURI BOOTHEEL AND THOSE PORTIONS OF WEST TENNESSEE AND NORTH MISSISSIPPI ALONG AND WEST OF A LINE FROM DYERSBURG TENNESSEE TO CHARLESTON MISSISSIPPI. A SLIGHT RISK OF SEVERE THUNDERSTORMS EXIST ELSEWHERE ACROSS THE MIDSOUTH FOR TONIGHT. A FEW TORNADOES...DAMAGING WINDS...AND LARGE HAIL ARE LIKELY. TORNADOES MAY BE STRONG ESPECIALLY IN THE MODERATE RISK AREA. THINK TONIGHT WILL BE A VERY ACTIVE NIGHT WEATHERWISE AS THUNDERSTORMS CONTINUE TO PUSH EASTWARD AND CONGEAL INTO ONE OR MORE MESOSCALE CONVECTIVE SYSTEMS. ALTHOUGH...DISCRETE SUPERCELLS MAY ALSO CONTINUE WELL INTO THE NIGHT. THE DRY LINE WILL PUSH INTO WESTERN MO AND WESTERN AR OVERNIGHT. HEAVY RAINFALL AND FLASH FLOODING WILL BE ON THE INCREASE WITH PRECIPITABLE WATER VALUES CLIMBING TO BETWEEN 1.5 AND 1.9 INCHES. ISSUED A WIND ADVISORY FOR STRONG AND GUSTY SOUTHERLY GRADIENT WINDS FOR EAST ARKANSAS...AND PORTIONS OF THE MISSOURI BOOTHEEL AND NORTHWEST MISSISSIPPI FROM LATE THIS MORNING INTO THIS EVENING. ON MONDAY...CONDITIONS MAY SETTLE DOWN BRIEFING LATE TONIGHT AND EARLY MONDAY MORNING WITH INSTABILITY TEMPORARILY WANING. BUT WITH STRONG UPPER LEVEL DYNAMICS AND HIGH SHEAR CONTINUING ALONG WITH SOME INSTABILITY...SOME THUNDERSTORMS STILL MAY POSE A THREAT OF BECOMING SEVERE EVEN EARLY IN THE MORNING. HOWEVER...THE MAIN THREAT OF ANOTHER SEVERE WEATHER OUTBREAK WILL OCCUR MONDAY AFTERNOON INTO MONDAY NIGHT SHIFTING TO EAST OF THE MS RIVER ACROSS MUCH OF NORTH MS INTO PORTIONS OF WEST TN. A FEW STRONG TORNADOES...DAMAGING WINDS...LARGE HAIL...AND HEAVY RAINFALL ARE ALL LIKELY ONCE AGAIN. THE DRY LINE WILL MOVE INTO EASTERN AR BY SUNSET MONDAY AS THE STRONG UPPER LOW OVER THE CENTRAL PLAINS MOVES EASTWARD. THE SITUATION BECOMES SOMEWHAT MUDDLED BY TUESDAY WITH ALL THE PREVIOUS CONVECTION AND THE MODELS NOT IN THE BEST AGREEMENT ON EXACTLY HOW FAST THE DRY LINE / COLD FRONT PUSHES TO THE EAST. RIGHT NOW...IT LOOKS LIKE THE BEST CHANCE FOR ORGANIZED SEVERE WEATHER WILL SHIFT TO NORTHEAST MS. DRY AND COOLER WEATHER WILL RETURN WEDNESDAY CONTINUING INTO THE BEGINNING OF NEXT WEEKEND. JCL && .AVIATION... 12Z TAF CYCLE CONDITIONS WILL START OFF...WITH TEMPO MVFR WEATHER AS FIRST LINE OF SHOWERS AND STORMS ALONG WARM FRONT LIFTS NORTHWARD LATE THIS MORNING THROUGH EARLY AFTERNOON. EXPECT A PERIOD OF DRY/VFR CONDITIONS FROM ROUGHLY MID AFTERNOON THROUGH EARLY EVENING BEFORE NEXT STRONGER LINE OF STORMS MOVES IN FROM THE WEST. CONDITIONS WILL THEN FALL TO TEMPO IFR...WITH A TRANSITION TO PREDOMINATE IFR/MVFR VERY LATE IN THE CYCLE. SOUTH WINDS AT 8-12KTS EARLY WILL STRENGTHEN THROUGHOUT THE DAY...WITH GUSTS IN THE 22-26KT RANGE CONTINUING THROUGH MOST OF THE NIGHT. JAB && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD- CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI- PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD- CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI- PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR DUNKLIN. FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH TUESDAY EVENING FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA- DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA- PONTOTOC-PRENTISS-QUITMAN-TALLAHATCHIE-TATE-TIPPAH- TISHOMINGO-TUNICA-UNION-YALOBUSHA. TN...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH TUESDAY EVENING FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER- FAYETTE-GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE- LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
639 AM CDT SUN APR 27 2014 .UPDATE... UPDATED FOR 12Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 455 AM CDT SUN APR 27 2014/ DISCUSSION... DANGEROUS SEVERE WEATHER OUTBREAK INCLUDING STRONG TORNADOES EXPECTED ACROSS PORTIONS OF THE MIDSOUTH FROM LATE THIS AFTERNOON INTO TONIGHT. ANOTHER SEVERE WEATHER OUTBREAK IS POSSIBLE MONDAY AND AGAIN TUESDAY FOR PORTIONS OF THE AREA. THE CALM BEFORE THE STORM WAS OBSERVED ACROSS THE MIDSOUTH EARLY THIS MORNING. SKIES WERE MOSTLY CLOUDY WITH A LIGHT SOUTHEAST WIND. TEMPERATURES WERE WARMER THAN THE LAST COUPLE OF MORNINGS WITH READINGS AT 4 AM RANGING FROM 59 DEGREES AT PARIS TN TO 72 DEGREES AT CLARKSDALE MS. A WARM FRONT WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST AND WILL MOVE THROUGH THE REGION THIS MORNING. THE ATMOSPHERE WAS MORE MOIST AND UNSTABLE SOUTHWEST OF THE WARM FRONT WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 60S. A FEW THUNDERSTORMS WERE BEGINNING TO BREAK OUT OVER SOUTHEAST AR. THE LATEST HIGH RESOLUTION RAPID REFRESH MODEL (HRRR) INDICATES SHOWERS AND THUNDERSTORMS INCREASING ALONG THE FRONT THIS MORNING AS IT MOVES INTO THE MIDSOUTH. AN UPPER LEVEL SHORT WAVE WILL ALSO HELP TO TRIGGER SHOWERS AND THUNDERSTORMS. ADJUSTED AND INCREASED THE POPS FOR THIS MORNING BASED ON THE LATEST HRRR MODEL. ATTENTION THEN TURNS TO A MUCH MORE SERIOUS SEVERE WEATHER AND FLASH FLOOD SETUP THAT WILL DEVELOP ACROSS THE MIDSOUTH BEGINNING BY LATE AFTERNOON. AS THE WARM FRONT MOVES TO THE NORTHEAST...VERY UNSTABLE AND MOIST AIR WILL PUSH INTO THE MIDSOUTH. A STRONG AND CLOSED UPPER LEVEL LOW WILL MOVE INTO WESTERN NE AND WESTERN KS. AN ASSOCIATED DRY LINE WILL EXTEND AT EARLY EVENING FROM EASTERN KS INTO EASTERN OK. PARAMETERS ARE COMING TOGETHER FOR THE FORMATION OF DISCRETE SUPERCELLS TO DEVELOP ACROSS THE ARKLATEX REGION INTO CENTRAL AR THIS AFTERNOON...THEN SPREAD INTO EASTERN AR AND PORTIONS OF NORTHWEST MS BY LATE AFTERNOON OR EARLY EVENING...THEN CROSSING INTO WEST TN ALONG THE MS RIVER THIS EVENING. SEVERE WEATHER PARAMETERS ARE IMPRESSIVE FOR THE POSSIBILITY OF SIGNIFICANT TORNADOES. MIXED LAYER MOST UNSTABLE CAPE WILL INCREASE TO BETWEEN 2000 AND 3000 J/KG WITH 0-1 KM STORM RELATIVE HELICITY INCREASING TO BETWEEN 300 AND 350 M2/S2. 850 WINDS INCREASE TO 50 KTS. A MODERATE RISK OF SEVERE THUNDERSTORMS EXIST ACROSS ALL OF EAST ARKANSAS...THE MISSOURI BOOTHEEL AND THOSE PORTIONS OF WEST TENNESSEE AND NORTH MISSISSIPPI ALONG AND WEST OF A LINE FROM DYERSBURG TENNESSEE TO CHARLESTON MISSISSIPPI. A SLIGHT RISK OF SEVERE THUNDERSTORMS EXIST ELSEWHERE ACROSS THE MIDSOUTH FOR TONIGHT. A FEW TORNADOES...DAMAGING WINDS...AND LARGE HAIL ARE LIKELY. TORNADOES MAY BE STRONG ESPECIALLY IN THE MODERATE RISK AREA. THINK TONIGHT WILL BE A VERY ACTIVE NIGHT WEATHERWISE AS THUNDERSTORMS CONTINUE TO PUSH EASTWARD AND CONGEAL INTO ONE OR MORE MESOSCALE CONVECTIVE SYSTEMS. ALTHOUGH...DISCRETE SUPERCELLS MAY ALSO CONTINUE WELL INTO THE NIGHT. THE DRY LINE WILL PUSH INTO WESTERN MO AND WESTERN AR OVERNIGHT. HEAVY RAINFALL AND FLASH FLOODING WILL BE ON THE INCREASE WITH PRECIPITABLE WATER VALUES CLIMBING TO BETWEEN 1.5 AND 1.9 INCHES. ISSUED A WIND ADVISORY FOR STRONG AND GUSTY SOUTHERLY GRADIENT WINDS FOR EAST ARKANSAS...AND PORTIONS OF THE MISSOURI BOOTHEEL AND NORTHWEST MISSISSIPPI FROM LATE THIS MORNING INTO THIS EVENING. ON MONDAY...CONDITIONS MAY SETTLE DOWN BRIEFING LATE TONIGHT AND EARLY MONDAY MORNING WITH INSTABILITY TEMPORARILY WANING. BUT WITH STRONG UPPER LEVEL DYNAMICS AND HIGH SHEAR CONTINUING ALONG WITH SOME INSTABILITY...SOME THUNDERSTORMS STILL MAY POSE A THREAT OF BECOMING SEVERE EVEN EARLY IN THE MORNING. HOWEVER...THE MAIN THREAT OF ANOTHER SEVERE WEATHER OUTBREAK WILL OCCUR MONDAY AFTERNOON INTO MONDAY NIGHT SHIFTING TO EAST OF THE MS RIVER ACROSS MUCH OF NORTH MS INTO PORTIONS OF WEST TN. A FEW STRONG TORNADOES...DAMAGING WINDS...LARGE HAIL...AND HEAVY RAINFALL ARE ALL LIKELY ONCE AGAIN. THE DRY LINE WILL MOVE INTO EASTERN AR BY SUNSET MONDAY AS THE STRONG UPPER LOW OVER THE CENTRAL PLAINS MOVES EASTWARD. THE SITUATION BECOMES SOMEWHAT MUDDLED BY TUESDAY WITH ALL THE PREVIOUS CONVECTION AND THE MODELS NOT IN THE BEST AGREEMENT ON EXACTLY HOW FAST THE DRY LINE / COLD FRONT PUSHES TO THE EAST. RIGHT NOW...IT LOOKS LIKE THE BEST CHANCE FOR ORGANIZED SEVERE WEATHER WILL SHIFT TO NORTHEAST MS. DRY AND COOLER WEATHER WILL RETURN WEDNESDAY CONTINUING INTO THE BEGINNING OF NEXT WEEKEND. JCL && .AVIATION... 12Z TAF CYCLE CONDITIONS WILL START OFF...WITH TEMPO MVFR WEATHER AS FIRST LINE OF SHOWERS AND STORMS ALONG WARM FRONT LIFTS NORTHWARD LATE THIS MORNING THROUGH EARLY AFTERNOON. EXPECT A PERIOD OF DRY/VFR CONDITIONS FROM ROUGHLY MID AFTERNOON THROUGH EARLY EVENING BEFORE NEXT STRONGER LINE OF STORMS MOVES IN FROM THE WEST. CONDITIONS WILL THEN FALL TO TEMPO IFR...WITH A TRANSITION TO PREDOMINATE IFR/MVFR VERY LATE IN THE CYCLE. SOUTH WINDS AT 8-12KTS EARLY WILL STRENGTHEN THROUGHOUT THE DAY...WITH GUSTS IN THE 22-26KT RANGE CONTINUING THROUGH MOST OF THE NIGHT. JAB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR- MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE- LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR DUNKLIN. FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA- LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS- QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION- YALOBUSHA. TN...FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE- GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE- LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
455 AM CDT SUN APR 27 2014 .DISCUSSION... DANGEROUS SEVERE WEATHER OUTBREAK INCLUDING STRONG TORNADOES EXPECTED ACROSS PORTIONS OF THE MIDSOUTH FROM LATE THIS AFTERNOON INTO TONIGHT. ANOTHER SEVERE WEATHER OUTBREAK IS POSSIBLE MONDAY AND AGAIN TUESDAY FOR PORTIONS OF THE AREA. THE CALM BEFORE THE STORM WAS OBSERVED ACROSS THE MIDSOUTH EARLY THIS MORNING. SKIES WERE MOSTLY CLOUDY WITH A LIGHT SOUTHEAST WIND. TEMPERATURES WERE WARMER THAN THE LAST COUPLE OF MORNINGS WITH READINGS AT 4 AM RANGING FROM 59 DEGREES AT PARIS TN TO 72 DEGREES AT CLARKSDALE MS. A WARM FRONT WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST AND WILL MOVE THROUGH THE REGION THIS MORNING. THE ATMOSPHERE WAS MORE MOIST AND UNSTABLE SOUTHWEST OF THE WARM FRONT WITH SURFACE DEW POINTS IN THE MIDDLE AND UPPER 60S. A FEW THUNDERSTORMS WERE BEGINNING TO BREAK OUT OVER SOUTHEAST AR. THE LATEST HIGH RESOLUTION RAPID REFRESH MODEL (HRRR) INDICATES SHOWERS AND THUNDERSTORMS INCREASING ALONG THE FRONT THIS MORNING AS IT MOVES INTO THE MIDSOUTH. AN UPPER LEVEL SHORT WAVE WILL ALSO HELP TO TRIGGER SHOWERS AND THUNDERSTORMS. ADJUSTED AND INCREASED THE POPS FOR THIS MORNING BASED ON THE LATEST HRRR MODEL. ATTENTION THEN TURNS TO A MUCH MORE SERIOUS SEVERE WEATHER AND FLASH FLOOD SETUP THAT WILL DEVELOP ACROSS THE MIDSOUTH BEGINNING BY LATE AFTERNOON. AS THE WARM FRONT MOVES TO THE NORTHEAST...VERY UNSTABLE AND MOIST AIR WILL PUSH INTO THE MIDSOUTH. A STRONG AND CLOSED UPPER LEVEL LOW WILL MOVE INTO WESTERN NE AND WESTERN KS. AN ASSOCIATED DRY LINE WILL EXTEND AT EARLY EVENING FROM EASTERN KS INTO EASTERN OK. PARAMETERS ARE COMING TOGETHER FOR THE FORMATION OF DISCRETE SUPERCELLS TO DEVELOP ACROSS THE ARKLATEX REGION INTO CENTRAL AR THIS AFTERNOON...THEN SPREAD INTO EASTERN AR AND PORTIONS OF NORTHWEST MS BY LATE AFTERNOON OR EARLY EVENING...THEN CROSSING INTO WEST TN ALONG THE MS RIVER THIS EVENING. SEVERE WEATHER PARAMETERS ARE IMPRESSIVE FOR THE POSSIBILITY OF SIGNIFICANT TORNADOES. MIXED LAYER MOST UNSTABLE CAPE WILL INCREASE TO BETWEEN 2000 AND 3000 J/KG WITH 0-1 KM STORM RELATIVE HELICITY INCREASING TO BETWEEN 300 AND 350 M2/S2. 850 WINDS INCREASE TO 50 KTS. A MODERATE RISK OF SEVERE THUNDERSTORMS EXIST ACROSS ALL OF EAST ARKANSAS...THE MISSOURI BOOTHEEL AND THOSE PORTIONS OF WEST TENNESSEE AND NORTH MISSISSIPPI ALONG AND WEST OF A LINE FROM DYERSBURG TENNESSEE TO CHARLESTON MISSISSIPPI. PORTIONS OF THIS AREA MAY BE UPGRADED TO HIGH RISK LATER THIS MORNING. A SLIGHT RISK OF SEVERE THUNDERSTORMS EXIST ELSEWHERE ACROSS THE MIDSOUTH FOR TONIGHT. A FEW TORNADOES... DAMAGING WINDS...AND LARGE HAIL ARE LIKELY. TORNADOES MAY BE STRONG ESPECIALLY IN THE MODERATE RISK AREA. THINK TONIGHT WILL BE A VERY ACTIVE NIGHT WEATHERWISE AS THUNDERSTORMS CONTINUE TO PUSH EASTWARD AND CONGEAL INTO ONE OR MORE MESOSCALE CONVECTIVE SYSTEMS. ALTHOUGH...DISCRETE SUPERCELLS MAY ALSO CONTINUE WELL INTO THE NIGHT. THE DRY LINE WILL PUSH INTO WESTERN MO AND WESTERN AR OVERNIGHT. HEAVY RAINFALL AND FLASH FLOODING WILL BE ON THE INCREASE WITH PRECIPITABLE WATER VALUES CLIMBING TO BETWEEN 1.5 AND 1.9 INCHES. ISSUED A WIND ADVISORY FOR STRONG AND GUSTY SOUTHERLY GRADIENT WINDS FOR EAST ARKANSAS...AND PORTIONS OF THE MISSOURI BOOTHEEL AND NORTHWEST MISSISSIPPI FROM LATE THIS MORNING INTO THIS EVENING. ON MONDAY...CONDITIONS MAY SETTLE DOWN BRIEFING LATE TONIGHT AND EARLY MONDAY MORNING WITH INSTABILITY TEMPORARILY WANING. BUT WITH STRONG UPPER LEVEL DYNAMICS AND HIGH SHEAR CONTINUING ALONG WITH SOME INSTABILITY...SOME THUNDERSTORMS STILL MAY POSE A THREAT OF BECOMING SEVERE EVEN EARLY IN THE MORNING. HOWEVER...THE MAIN THREAT OF ANOTHER SEVERE WEATHER OUTBREAK WILL OCCUR MONDAY AFTERNOON INTO MONDAY NIGHT SHIFTING TO EAST OF THE MS RIVER ACROSS MUCH OF NORTH MS INTO PORTIONS OF WEST TN. A FEW STRONG TORNADOES...DAMAGING WINDS...LARGE HAIL...AND HEAVY RAINFALL ARE ALL LIKELY ONCE AGAIN. THE DRY LINE WILL MOVE INTO EASTERN AR BY SUNSET MONDAY AS THE STRONG UPPER LOW OVER THE CENTRAL PLAINS MOVES EASTWARD. THE SITUATION BECOMES SOMEWHAT MUDDLED BY TUESDAY WITH ALL THE PREVIOUS CONVECTION AND THE MODELS NOT IN THE BEST AGREEMENT ON EXACTLY HOW FAST THE DRY LINE / COLD FRONT PUSHES TO THE EAST. RIGHT NOW...IT LOOKS LIKE THE BEST CHANCE FOR ORGANIZED SEVERE WEATHER WILL SHIFT TO NORTHEAST MS. DRY AND COOLER WEATHER WILL RETURN WEDNESDAY CONTINUING INTO THE BEGINNING OF NEXT WEEKEND. JCL && .AVIATION... 06Z TAF CYCLE TAFS WILL GET A BIT MORE COMPLEX OVER THE NEXT 12 HOURS AS A WARM FRONT SURGES NORTH AND BETTER CHANCE OF ORGANIZED POSSIBLY SEVERE THUNDERSTORMS APPROACHES THE MIDSOUTH LATE TOMORROW. WE COULD SEE SOME THUNDERSTORMS ASSOCIATED WITH THE WARM FRONT LATE TONIGHT OR EARLY TOMORROW. INCLUDED A FEW HOURS OF VICINITY THUNDER AT MEM FROM MID MORNING TO EARLY AFTERNOON. THINK WE WILL SEE A BREAK IN WIDESPREAD THUNDER AS THE WARM FRONT SURGES NORTH...WITH PARTLY CLOUDY SKIES DURING MUCH OF THE MIDDAY TIME FRAME INTO THE EVENING HOURS. ADDITIONAL THUNDERSTORMS...LIKELY PREVAILING IS EXPECTED LATE IN THE PERIOD...WILL ADD PREVAILING THUNDER AT MEM AT 00Z AND CARRY IT THROUGH THE END OF THE TAF CYCLE. PREVAILING THUNDER WILL START AN HOUR OR TWO EARLIER AT JBR AND 2-3 HOURS LATER AT MKL AND TUP. WINDS WILL BE STRONG AND GUSTY ASSOCIATED WITH THUNDERSTORMS AND VIS WILL LIKELY DROP TO IFR CONDITIONS FOR BRIEF PERIODS OF TIME. WILL CARRY 3SM IN PREVAILING THUNDER. EXPECT NUMEROUS AMENDMENTS BASED ON RADAR TOMORROW INTO TOMORROW EVENING AS SHOWERS AND THUNDERSTORMS DEVELOP...APPROACH AND MOVE AWAY FROM TAF SITES. WINDS WILL BE SOUTHERLY GENERALLY 10 KT TONIGHT INCREASING TO 10-20 TOMORROW WITH GUSTS TO 25KT. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR- MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE- LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR DUNKLIN. FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA- LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS- QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION- YALOBUSHA. TN...FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE- GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE- LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1218 AM CDT SUN APR 27 2014 .UPDATE... UPDATED FOR 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 939 PM CDT SAT APR 26 2014/ DISCUSSION...01Z SURFACE ANALYSIS PLACES A SURFACE LOW OVER NORTHEAST COLORADO WITH A WARM FRONT EXTENDING SOUTHEAST ACROSS PORTIONS OF EASTERN KANSAS...NORTHWEST TO SOUTHEAST ARKANSAS...AND CENTRAL MISSISSIPPI...AND A DRY LINE LOCATED ACROSS WESTERN KANSAS...THE TEXAS/OKLAHOMA PANHANDLE AND WEST TEXAS. 00Z UPPER AIR ANALYSIS ALONG WITH WATER VAPOR SATELLITE TRENDS /WSR-88D VAD WIND PROFILES INDICATE AN UPPER LEVEL RIDGE PRESENT ACROSS THE LOWER MISSISSIPPI VALLEY. AS OF 8 PM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE IN THE 70S AT MOST LOCATIONS. 00Z UPPER AIR SOUNDINGS FROM KLZK/KSGF SHOW AN 850-800 MB CAPPING INVERSION PRESENT ACROSS THE LOWER MISSISSIPPI VALLEY WHILE THE CAPPING INVERSION IS WEAKER AT KJAN/KSHV. LATEST 00Z WRF IS SLOWLY BEGINNING TO COME IN AND THUS FAR INDICATES THE WARM FRONT CURRENTLY SOUTH AND WEST OF THE FORECAST AREA WILL GRADUALLY LIFT NORTH BY SUNDAY MORNING AND A MID LEVEL SHORTWAVE TROUGH WILL MOVE NORTHEAST ACROSS THE LOWER MISSISSIPPI VALLEY. THIS WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE MID SOUTH SUNDAY MORNING. THE 00Z WRF AGREES WITH THE 26/23Z HRRR RUN THUS FAR. WILL MAKE SOME MINOR ADJUSTMENTS TO TIMING OF POPS SUNDAY MORNING GIVEN CURRENT MODEL TRENDS. WILL MAKE ADJUSTMENTS TO ALL OTHER ELEMENTS AS NEEDED DURING THIS TIMEFRAME. OTHERWISE...THE REMAINDER OF THE FORECAST IS IN EXCELLENT SHAPE OVERALL. UPDATED GRIDS WILL BE AVAILABLE SHORTLY. CJC && .PREV DISCUSSION... /ISSUED 642 PM CDT SAT APR 26 2014/ UPDATE...AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 243 PM CDT SAT APR 26 2014/ SEVERE WEATHER EXPECTED ACROSS THE MIDSOUTH SUNDAY THROUGH TUESDAY... TRANQUIL WEATHER CONTINUES ACROSS THE MIDSOUTH THIS AFTERNOON. SOUTHERLY WINDS HAVE ALLOWED TEMPERATURES TO REACH INTO THE LOWER 80S. THE SOUTHERLY WINDS WILL CONTINUE TO BRING WARM...MOIST AIR FROM THE GULF OF MEXICO INTO THE MIDSOUTH THROUGH TUESDAY. A POTENT LOW PRESSURE SYSTEM HAS MOVED OUT OF THE ROCKIES INTO NORTHWEST KANSAS THIS AFTERNOON. THIS SYSTEM WILL BRING SEVERAL ROUNDS OF SEVERE WEATHER AS THE SYSTEM INTERACTS WITH A WARM UNSTABLE AIRMASS. SEVERE WEATHER WILL BE POSSIBLE BEGINNING ON SUNDAY AND WILL CONTINUE THROUGH TUESDAY. TONIGHT...QUIET WEATHER WILL CONTINUE. CLOUDS WILL BEGIN TO INCREASE BY LATER IN THE EVENING INTO THE OVERNIGHT HOURS. LOWS WILL BE IN THE UPPER 50S TO MID 60S. ON SUNDAY...A SHORTWAVE AHEAD OF THE UPPER LOW WILL MOVE THROUGH THE MIDSOUTH. THIS WILL PRODUCE THE FIRST ROUND OF ACTIVITY. SHOWERS AND THUNDERSTORMS WILL BLOSSOM ACROSS EASTERN ARKANSAS...THE MISSOURI BOOTHEEL...NORTHWEST MISSISSIPPI...AND EXTREME WEST TENNESSEE AFTER 10 AM. DEWPOINTS ARE CURRENTLY IN THE UPPER 40S TO MID 50S. HOWEVER...OVERNIGHT EXPECT DEWPOINTS TO RISE INTO THE LOWER TO MID 60S. BY SUNDAY AFTERNOON...UPPER 60 DEWPOINTS WILL BE COMMON ACROSS THE MISSISSIPPI DELTA. THE COMBINATION OF THE SHORTWAVE AND THE WARM MOIST AIR MAY CAUSE A FEW OF THESE THUNDERSTORMS TO BECOME SEVERE. THE SHORTWAVE WILL PUSH EAST BY 4 PM THUS ACTIVITY MAY BEGIN TO DISSIPATE OR MOVE EAST BY THIS TIME. SECOND ROUND OF ACTIVITY WILL PUSH INTO THE EASTERN ARKANSAS BETWEEN 7-9 PM. THESE THUNDERSTORMS WILL DEVELOP ALONG THE DRY LINE ACROSS EASTERN OKLAHOMA AND WESTERN ARKANSAS DURING THE AFTERNOON HOURS AND WILL PUSH EAST DURING THE EVENING HOURS. THESE STORMS HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER ACROSS THE WESTERN HALF OF THE CWA. DAMAGING WINDS...LARGE HAIL AND A FEW STRONG TORNADOES ARE POSSIBLE. AS THE STORMS PUSH EAST ACROSS THE MISSISSIPPI RIVER AROUND MIDNIGHT INTO THE OVERNIGHT HOURS...QUESTIONS EMERGE IF THEY WILL REMAIN SEVERE DUE TO WAINING INSTABILITY. ON MONDAY...LINGERING SHOWERS AND THUNDERSTORMS FROM OVERNIGHT CONVECTION MAY BE OCCURRING ACROSS AREAS OF WEST TENNESSEE NEAR THE TENNESSEE RIVER AND NORTHEAST MISSISSIPPI. EXPECT THE DRY LINE TO HAVE ADVANCED TO NEAR THE MISSISSIPPI RIVER BY MONDAY MORNING. THE LINE WILL BE THE SOURCE OF REGENERATION OF SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON. AGAIN...THESE STORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL...DAMAGING WINDS AND A FEW STRONG TORNADOES. THE ACTIVITY WILL PUSH EAST DURING THE OVERNIGHT HOURS INTO WEST TENNESSEE AND NORTHEAST MISSISSIPPI. AGAIN QUESTIONS EMERGE ON IF THE ACTIVITY WILL REMAIN SEVERE INTO THE OVERNIGHT HOURS AS INSTABILITY WAINS. ON TUESDAY...REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS WILL OCCUR ALONG AREAS OF WEST TENNESSEE NEAR THE TENNESSEE RIVER INTO NORTHEAST MISSISSIPPI. AGAIN...SOME OF THESE THUNDERSTORMS COULD BECOME SEVERE WITH BEST CHANCES OCCURRING ACROSS NORTHEAST MISSISSIPPI. EXPECT ACTIVITY TO PUSH EAST INTO ALABAMA/MIDDLE TENNESSEE BY EARLY TUESDAY EVENING. THE SHOWERS AND THUNDERSTORMS WILL PRODUCE HEAVY RAIN AND DUE TO THE MULTIPLE ROUNDS OF THUNDERSTORM ACTIVITY WILL GO AHEAD AND ISSUE A FLASH FLOOD WATCH. WIDESPREAD THREE TO FIVE INCHES OF RAINFALL IS EXPECTED WITH ISOLATED HIGHER AMOUNTS. A WIND ADVISORY MAY BECOME NECESSARY DURING THE SUNDAY THROUGH AT LEAST MONDAY TIME FRAME AS GUSTY SOUTHERLY WINDS WILL OCCUR AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WEDNESDAY THROUGH EARLY NEXT WEEKEND...UPPER LOW WILL MEANDER AROUND THE UPPER MIDWEST TO THE OHIO VALLEY. WRAP AROUND SHOWERS COULD SKIRT NORTHERN AREAS OF THE MIDSOUTH BUT FOR NOW WILL LEAVE DRY CONDITIONS. EXPECT COOLER CONDITIONS WITH HIGHS IN THE MID TO UPPER 60S AND LOWS IN THE 40S. KRM && .AVIATION... 06Z TAF CYCLE TAFS WILL GET A BIT MORE COMPLEX OVER THE NEXT 12 HOURS AS A WARM FRONT SURGES NORTH AND BETTER CHANCE OF ORGANIZED POSSIBLY SEVERE THUNDERSTORMS APPROACHES THE MIDSOUTH LATE TOMORROW. WE COULD SEE SOME THUNDERSTORMS ASSOCIATED WITH THE WARM FRONT LATE TONIGHT OR EARLY TOMORROW. INCLUDED A FEW HOURS OF VICINITY THUNDER AT MEM FROM MID MORNING TO EARLY AFTERNOON. THINK WE WILL SEE A BREAK IN WIDESPREAD THUNDER AS THE WARM FRONT SURGES NORTH...WITH PARTLY CLOUDY SKIES DURING MUCH OF THE MIDDAY TIME FRAME INTO THE EVENING HOURS. ADDITIONAL THUNDERSTORMS...LIKELY PREVAILING IS EXPECTED LATE IN THE PERIOD...WILL ADD PREVAILING THUNDER AT MEM AT 00Z AND CARRY IT THROUGH THE END OF THE TAF CYCLE. PREVAILING THUNDER WILL START AN HOUR OR TWO EARLIER AT JBR AND 2-3 HOURS LATER AT MKL AND TUP. WINDS WILL BE STRONG AND GUSTY ASSOCIATED WITH THUNDERSTORMS AND VIS WILL LIKELY DROP TO IFR CONDITIONS FOR BRIEF PERIODS OF TIME. WILL CARRY 3SM IN PREVAILING THUNDER. EXPECT NUMEROUS AMENDMENTS BASED ON RADAR TOMORROW INTO TOMORROW EVENING AS SHOWERS AND THUNDERSTORMS DEVELOP...APPROACH AND MOVE AWAY FROM TAF SITES. WINDS WILL BE SOUTHERLY GENERALLY 10 KT TONIGHT INCREASING TO 10-20 TOMORROW WITH GUSTS TO 25KT. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR- MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA- LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS- QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION- YALOBUSHA. TN...FLASH FLOOD WATCH FROM THIS EVENING THROUGH TUESDAY EVENING FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE- GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE- LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
741 PM CDT MON APR 28 2014 .DISCUSSION... THE DRY LINE/COLD FRONT HAS REVERSED AND WAS MOVING INLAND AT 730 PM. DEWPOINTS ON THE NORTHWEST SIDE OF THE BOUNDARY WERE IN THE MID 30S...WHILE TO ITS SOUTHEAST THE DEWPOINTS WERE IN THE LOWER 70S. A DRASTIC CHANGE IN THE HUMIDITY LEVELS CAN BE FELT WHEREVER THE BOUNDARY CROSSES. THE LATEST RAP LOOKS TO HAVE A GOOD HANDLE ON THE MOVEMENT OF THE BOUNDARY THROUGH TONIGHT AND TUESDAY MORNING. STILL THINK PATCHY FOG IS POSSIBLE LATER TONIGHT ON THE SOUTHERN SIDE OF THE FRONT. FORECAST UPDATE MAINLY TO TWEAK THE DEWPOINT AND HUMIDITY GRIDS. 40 && .PREV DISCUSSION... /ISSUED 631 PM CDT MON APR 28 2014/ DISCUSSION... 00Z TAF DISCUSSION IN AVIATION SECTION. AVIATION... SFC ANALYSIS/RADAR IMAGERY AND EVEN VIS SATELLITE IMAGERY SHOW A DRY LINE PUSHING BACK NORTH WITH VERY MOIST BOUNDARY LAYER SOUTH OF THE BOUNDARY AND DRY NORTH. BOUNDARY SHOULD PUSH BACK NORTH AND SHOULD SEE A RAPID RISE IN SFC MOISTURE AS IT DOES. MAY GET SOME LOW STRATUS OR EVEN SOME PATCHY FOG TO DEVELOP AS A RESULT. DO NOT THINK THERE WILL BE VERY MUCH IN THE WAY OF MVFR CIGS AS THERE MAY BE ENOUGH MIXING OVERNIGHT. STRONGER FRONTAL PUSH IS EXPECTED TOMORROW MORNING WITH MAINLY NW WINDS IN THE AFTERNOON WHICH COULD BE GUSTY. SHOULD ALLOW FOR VFR CIGS ON WEDNESDAY. 39 PREV DISCUSSION... /ISSUED 347 PM CDT MON APR 28 2014/ DISCUSSION... VERY WARM ACROSS SOUTHEAST TEXAS THIS AFTERNOON AS SKIES HAVE CLEARED AND THE DRY LINE HAS MADE IT THROUGH THE CITY OF HOUSTON. THE DRY LINE IS EXPECTED TO RETREAT THIS EVENING AS IT SLOWLY WEAKENS WHICH WILL ALLOW MOISTURE TO WORK ITS WAY BACK INLAND. MOST LIKELY IT SHOULD STALL OUT AROUND A BRENHAM TO CONROE TO LIVINGSTON LINE. WITH THE MOISTURE RETURN PATCHY FOG WILL BE POSSIBLE SOUTH OF THE DRY LINE. A COLD FRONT IS STILL ON TRACK TO PUSH THROUGH THE AREA TOMORROW AFTERNOON. THE GFS REMAINS THE FASTEST WITH THE FRONT PUTTING IT AT THE COAST AROUND NOON WHILE THE ECMWF AND NAM PUT THE FRONT AT THE COAST CLOSER TO 6 PM. HAVE CONTINUED TO PREFER THE ECMWF TIMING. HIGH TEMPERATURES TOMORROW COULD VARY BY 5 TO 10 DEGREES DEPENDING ON WHICH SIDE OF THE COLD FRONT ONE IS ON. WEDNESDAY AND THURSDAY LOOK VERY NICE AS HIGH TEMPERATURES REMAIN WELL BELOW NORMAL. THIS IS ALL THANKS TO SOUTHEAST TEXAS BEING ON THE EAST SIDE OF AN UPPER LEVEL LOW BRINGING MUCH COOLER 850 MB TEMPERATURES INTO THE AREA. A SHORT WAVE WILL DIVE SOUTHWARDS ON THE BACK SIDE OF THE LOW HELPING TO REINFORCE THE LONG WAVE TROUGH. THE SHORT WAVE WILL THEN MOVE OVER THE AREA FRIDAY INTO SATURDAY. THIS WILL ALLOW CLOUDS TO RETURN TO THE AREA THURSDAY AFTERNOON IN FRIDAY MORNING. THE EURO HAD BEEN HINTING AT SOME RAIN CHANCES WITH THE SHORT WAVE IN PREVIOUS RUNS BUT HAS SINCE BACKED OFF. THIS MAKES SENSE GIVEN THE LACK OF MOISTURE OVER THE AREA. KEPT WITH CURRENT FORECAST TRENDS AND REDUCED POPS. 23 MARINE... WEAKENING WINDS AND LOWERING SEAS CAN BE EXPECTED THROUGH TONIGHT. A COLD FRONT WILL MOVE INTO THE COASTAL WATERS LATE TUESDAY AFTERNOON INTO TUESDAY EVENING WITH MODERATE STRONG NORTH WINDS AND BUILDING SEAS EXPECTED IN IT WAKE. BEHIND THE FRONT...CAUTION FLAGS WILL BE NEEDED...AND ADVISORIES ARE POSSIBLE. MODERATE NORTH TO NORTHEAST WINDS ARE EXPECTED WEDNESDAY AND THURSDAY. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 59 82 49 74 46 / 10 10 0 0 0 HOUSTON (IAH) 64 86 53 76 49 / 10 10 0 0 0 GALVESTON (GLS) 72 84 62 76 60 / 10 20 0 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
310 PM CDT SUN APR 27 2014 .DISCUSSION... VISIBLE SATELLITE SHOWS DRY LINE CLEARLY ACROSS CENTRAL TEXAS THIS AFTERNOON. THE DRY LINE IS NOW JUST AT DALLAS- FORT WORTH AND IS EXPECTED TO PUSH EAST THROUGH THE NIGHT. GLOBAL MODELS CONTINUE TO OVER DUE PRECIP ACROSS THE AREA AS THE CAP HAS REMAINED STRONG. A SPECIAL 18Z SOUNDING LAUNCH FROM TEXAS A&M SHOWS A PRETTY STOUT CAP IN PLACE AT 750 MB. CONVECTIVE TEMPERATURE FROM THIS SOUNDING IS IN THE MID 90S WHICH IS VERY UNLIKELY TO OCCUR THIS AFTERNOON. HIGH RES HRRR AND TEXAS TECH WRF STRUGGLE TO DEVELOP PRECIP THIS AFTERNOON INTO EVENING. THE HRRR AND TEXAS TECH WRF DO TRY TO DEVELOP SOMETHING IN HOUSTON COUNTY BUT QUICKLY MOVE IT OFF TO THE NORTHEAST. UPPER LEVEL DIFFLUENCE ALSO APPEARS TO BE NOW MOVING OFF TO THE NORTH AND EAST WITH THE ADVANCING UPPER LEVEL LOW. DUE TO THE MENTIONED ABOVE HAVE TRIMMED BACK POPS AND THE MENTION OF SEVERE. TOMORROW THE DRY LINE WILL STALL OUT ACROSS THE AREA GENERALLY ALONG A LINE FROM WHARTON TO HARRIS TO SAN JANCINTO COUNTY. BEHIND THE DRY LINE LIGHT WEST TO NORTHWEST WINDS AND MOSTLY CLEAR SKIES WILL ALLOW TEMPERATURES TO QUICKLY RISE. HIGHS IN THE LOWER 90S LOOKS LIKELY. NEAR THE COAST TEMPERATURES SHOULD REMAIN MORE CHECKED DUE TO ONSHORE WINDS AND HIGHER DEWPOINTS. STILL EXPECT TEMPERATURES TO REACH THE LOWER 80S. TUESDAY MORNING THE DRY LINE WILL START TO RETREAT AS THE NEXT COLD FRONT APPROACHES THE AREA. WITH LIGHT WINDS AND RISING DEWPOINTS CAN`T RULE OUT SOME PATCHY FOG TUESDAY MORNING. THE SURFACE COLD FRONT IS THEN EXPECTED TO SLOWLY PUSH THROUGH THE AREA ON TUESDAY. THE GFS REMAINS VERY QUICK WITH THE FRONT WHILE THE ECMWF... CANADIAN AND NAM 12 ARE SLOWER. HAVE LEANED TOWARDS THE EURO AS FRONTS USUALLY SLOW DOWN IN THE AFTERNOON IN COMBINATION WITH THE OCCLUDING MID- LATITUDE CYCLONE. FOR THE REST OF THE WORK WEEK BELOW NORMAL TEMPERATURES WILL BE THE STORY AS SOUTHEAST TEXAS REMAINS ON THE BACK SIDE OF THE UPPER LEVEL LOW. THURSDAY A SHORT WAVE WILL BEGIN TO DIVE SOUTHWARDS HELPING TO REINFORCE THE LONG WAVE TROUGH. THIS SHORT WAVE WILL PUSH A WEAK WIND SHIFT THROUGH THE AREA. AS THE VORT MAX MOVES SOUTHWARDS MODELS ARE GENERATING SOME QPF. MOISTURE WILL BE LIMITED BUT CAN`T RULE OUT THE CHANCE COMPLETELY. CURRENT FORECAST LOOKS ON TRACK WITH THIS. 23 && .MARINE... MODERATE TO STRONG ONSHORE WINDS WILL CONTINUE THROUGH TONIGHT UNDER A TIGHT PRESSURE GRADIENT. CAUTION FLAGS ARE UP FOR THE BAYS...AND ADVISORIES ARE IN EFFECT FOR THE COASTAL WATERS. WINDS AND SEAS WILL COME DOWN ON MONDAY AS THE GRADIENT WEAKENS. A STRONG COLD FRONT THAT IS EXPECTED TO BE NEAR THE COAST LATE TUESDAY AFTERNOON OR EARLY TUESDAY EVENING WILL MOVE THROUGH THE WATERS TUESDAY NIGHT. BEHIND THE FRONT... CAUTION FLAGS ARE LIKELY AND ADVISORIES MIGHT BE NEEDED FOR STRENGTHENING NORTH WINDS AND BUILDING SEAS. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 65 91 62 82 51 / 10 10 10 10 10 HOUSTON (IAH) 72 91 68 86 55 / 20 20 10 10 10 GALVESTON (GLS) 73 82 72 82 62 / 20 10 10 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...FORT BEND...GALVESTON... HARRIS...JACKSON...LIBERTY...MATAGORDA...WHARTON. GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY. SMALL CRAFT ADVISORY UNTIL 4 AM CDT MONDAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$ DISCUSSION...23 AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1127 PM CDT SAT APR 26 2014 .UPDATE... The Pacific cold front is visible on the west TX radars and continues to move east toward the CWA. With CINH increasing with the loss of surface heating, any potential precipitation will be tied to the interaction of the front with the shallow, moist airmass in place across the region. Confidence is low that we`ll see storms develop along the boundary, but there is enough of a threat that we`ve opted to leave in a slight chance of thunderstorms overnight. Gusty south winds will veer to the southwest late tonight, becoming westerly at 25-35 mph (gusting up to 45 mph at times) by mid-morning. The combination of these strong winds, warm temperatures, and relative humidities near 10 percent will result in dangerous fire weather conditions through sunset. The current Red Flag Warning looks good. We`re also on track with the Wind Advisory for tomorrow, with the strongest winds expected over the Big Country and Concho Valley. && .AVIATION... /06Z TAFS/ Showers and thunderstorms have had a difficult time materializing across the forecast area and chances continue to diminish that we will see anything during the overnight period. While convection cannot be ruled out, I did remove any mention of thunder from the 06z TAF package. Low clouds are expected to move into the northwest Hill Country for a few hours tonight, primarily in the area of KBBD and KJCT. I included MVFR ceilings for a few hours. Winds will veer to the southwest late tonight as a Pacific cold front moves into the area. This front has moved into West TX and can be seen on the latest radar imagery. By 15z, sustained westerly crosswinds winds of 20-25 kts are expected across West Central TX. Gusts will generally be in the 30-35 kt range, but KABI/KSJT may see occasional gusts approaching 40 kts. Thus, an Airport Weather Warning will likely be required for KABI. Blowing dust is expected across the area, which may reduce visibilities at times. Wind speeds will decrease after 00z, maintaining a general westerly component. Johnson && .PREV DISCUSSION... /ISSUED 620 PM CDT SAT APR 26 2014/ AVIATION... /00Z TAFS/ The primary concern regarding the 00z TAF package is the potential for convection during the evening and overnight hours. Model guidance continues to be all over the place, ranging from isolated evening thunderstorms becoming more widespread overnight, to basically nothing. We have a few cells developing at this time and I think the latter solution is more likely with the best chance of precipitation occurring across the Big Country. I do have VCTS included for a few hours at KABI but left the remaining sites dry for now. Additional development of thunderstorms is possible overnight as a Pacific cold front moves across the CWA, but confidence remains low. We`ll see gusty winds overnight with low-level moisture increasing ahead of the Pacific cold front. I expect MVFR ceilings to affect KJCT and KBBD for a few hours after midnight but strong west winds will bring much drier air in from west TX, quickly shunting that moisture off to the east. Sustained westerly winds of 20-30 kts, gusting to around 35 kts, are expected tomorrow at KSJT and KABI with slightly lower wind speeds at the remaining terminals. The result will be strong west to east crosswinds and patchy blowing dust causing occasional visibility reductions. An Airport Weather Warning will likely be issued later for KABI due to these strong winds. Johnson PREV DISCUSSION... /ISSUED 415 PM CDT SAT APR 26 2014/ SHORT TERM... (Tonight and Sunday) Conditionally severe thunderstorm threat tonight, mainly in the Big Country and Concho Valley. West Central Texas is certainly unstable with RUC SB CAPES up to 3000 J/KG, but warm air aloft may prevent storms from occurring. Surface Observations show only weak low level convergence along the dryline. Some virga indicated in the Big Country from Abilene to west of Wichita Falls, but the mid level instability associated with it appears to be fairly high, above 10000 FT AGL. Both the GFS and the HRRR models develop isolated storms in the Big Country this evening, with the GFS the only one to develop storms later tonight, as a Pacific front catches up with dryline towards midnight. Region should become more unstable as cooler air aloft moves in as an upper trough approaches. There will also be stronger low level convergence, with west winds behind the Pacific front. But storm development is still conditional. Strong downslope west warming winds expected Sunday behind the Pacific Front. Should see Wind Advisory criteria of 25 to 35 mph, with gusts to 45 mph by mid-morning. Have a Red Flag Warning for dangerous fire conditions from 11 AM to 10 PM. FIRE WEATHER... A Red Flag Warning for fire weather is in effect for West Central Texas from 11 AM to 10 PM. Dangerous fire weather conditions Sunday as the dryline and Pacific front sweep through, bringing dry and windy west winds Minimum RH values will fall near 10 percent with 20 foot west winds of 20 to 30 mph gusting to 35 mph. Added Mason and San Saba counties to the Red Flag Warning as 20 foot winds will be close to 20 mph. Elevated fire weather conditions are also expected Monday due to gusty west winds and very dry conditions. LONG TERM... (Sunday night through next Saturday) Warm and dry weather will prevail on Monday, with cooler temperatures Tuesday through next Friday. The large closed upper low will be centered over the Central Plains late this weekend, and will move slowly northeast to the Great Lakes region by mid week. Associated surface low currently over eastern Colorado this evening, will move northeast into eastern Nebraska Sunday evening. Monday will be another warm day with gusty west winds once again with afternoon highs in the mid and upper 80s. A cold front will move across the area Monday night, bringing much cooler temperatures for Tuesday, with highs mainly in the 70s. Northwest flow aloft will prevail across the area Tuesday through much of next week. A persistent surface ridge will remain in place and will result in unseasonably cool temperatures for West Central Texas through Friday. High temperatures through Friday will be mainly in the 70s, with overnight lows in the 40s and 50s. Warmer weather is expected next weekend with near seasonal temperatures. No rain is forecast through the period. && .PRELIMINARY POINT TEMPS/POPS... Abilene 63 88 51 83 48 / 40 0 0 0 0 San Angelo 63 90 51 88 49 / 30 0 0 0 0 Junction 66 92 50 90 47 / 30 5 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING from 11 AM to 10 PM CDT Sunday FOR THE FOLLOWING ZONES: Brown...Callahan...Coke...Coleman...Concho... Crockett...Fisher...Haskell...Irion...Jones...Kimble...Mason... McCulloch...Menard...Nolan...Runnels...San Saba...Schleicher... Shackelford...Sterling...Sutton...Taylor...Throckmorton...Tom Green. WIND ADVISORY from 10 AM to 7 PM CDT Sunday FOR THE FOLLOWING ZONES: Callahan...Coke...Coleman...Concho...Crockett...Fisher... Haskell...Irion...Jones...Nolan...Runnels...Schleicher... Shackelford...Sterling...Taylor...Throckmorton...Tom Green. && $$ 25
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AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
747 PM EDT MON APR 28 2014 .SYNOPSIS... A NEARLY STATIONARY FRONT WILL REMAIN JUST TO THE SOUTH AND WEST OF THE REGION INTO TUESDAY...AND THEN EVENTUALLY LIFT NORTH AS A WARM FROM EARLY WEDNESDAY. A LARGE AND COMPLEX STORM SYSTEM LOCATED OVER THE CENTRAL UNITED STATES WILL SLOWLY MOVE EAST THROUGH MIDWEEK. THIS SYSTEM WILL PROVIDE SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY...SOME WITH VERY HEAVY RAIN AND A SLIGHT RISK OF SEVERE WEATHER. && .NEAR TERM /THROUGH TUESDAY/... AS OF 630 PM EDT MONDAY... FORECAST UPDATED TO ACCOUNT FOR MOVEMENT OF SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE WRN CWA. 19Z HRRR HANDLING THIS PRETTY WELL AND WILL SEE THINGS DRYING OUT OVER THE FAR WRN CWA WHILE THE MAIN BATCH OF SHOWERS HEADS ENE OVER THE BLUE RIDGE INTO THE PIEDMONT THROUGH 8-9 PM. CONVECTION WEAKENED AS IT MOVED INTO THE WEDGE OF STABLE AIR LOCATED MAINLY EAST OF INTERSTATE 77 IN VA/SRN WV. MODIFICATIONS WERE MADE TO TEMPS/SKY COVER AS WELL WITH LESS CLOUDS OVER NC EARLY ON. NEXT ROUND OF SHOWERS MAKES INTO THE CWA AFTER MIDNIGHT. PREVIOUS DISCUSSION AT 330 PM EDT MONDAY... DEEP UPPER LOW NOT MAKING MUCH PROGRESS THROUGH THE MISSISSIPPI VALLEY TONIGHT AND TUESDAY...WITH THE CENTER OF THE LOW ONLY REACHING EASTERN IOWA BY LATE THURSDAY. BUT UPPER LOW IS SO LARGE AND UPPER RIDGING MOVES FAR ENOUGH OFFSHORE TO RESULT IN PERSISTENT SOUTHWEST FLOW ACROSS THE FORECAST AREA. PIECES OF SHORT WAVE ENERGY TRACK OVER THE RIDGE BUT CHALLENGING TO TIMING OF THESE SMALL FEATURES. BUT MODELS LINE UP PRECIPITATION ALONG THE WESTERN SIDE OF THE COUNTY WARNING AREA BY 12Z/8AM TUESDAY. WILL STAY WITH A CATEGORICAL PROBABILITY OF PRECIPITATION TUESDAY MORNING IN THE WESTERN MOUNTAINS. MODELS ERODE EASTERN SIDE OF THE WEDGE AND BRING BETTER INSTABILITY AND CAPES AROUND 2500 J/KG INTO SOUTHERN VIRGINIA TUESDAY AFTERNOON. AREA WITH HIGHEST THREAT OF THUNDERSTORMS ALSO HAS PRECIPITABLE WATER VALUES JUST ABOVE 1.5 INCHES. HEAVY RAIN AND SEVERE THUNDERSTORMS WILL BE A THREAT IN THE SOUTHEAST COUNTY WARNING AREA IN THE AFTERNOON. SEVERE THREAT WILL BE ENHANCED WITH INCREASED SHEAR ALONG THE RETREATING WARM FRONT. CLOUDS AND PRECIPITATION WILL HOLD TEMPERATURES NEAR EVENING VALUES. WILL HAVE OVERNIGHT LOWS CLOSE TO BIAS CORRECTED LOCAL WRF GUIDANCE BUT MORE SO BASED ON CURRENT OBSERVATIONS. AS USUAL...MAX TEMPERATURES ON TUESDAY WILL DEPEND ON POSITION OF THE WEDGE AND THE RESULTING BREAKS IN THE CLOUD COVER ON THE WARM SIDE OF THE BOUNDARY. MET GUIDANCE SEEMS TO HAVE A BETTER HANDLE ON THE WEDGE FOR TUESDAY BUT WILL BE ADJUSTING ACROSS THE SOUTHERN COUNTY WARNING AREA. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 410 PM EST MONDAY... FAIRLY SIGNIFICANT SHORT WAVE LIFTING NORTHEAST AROUND LARGE TROUGH IS LIKELY TO BRING HEAVY BAND OF THUNDERSTORMS ACROSS THE APPALACHIANS OVERNIGHT...BUT WEDGE MAY REMAIN IN PLACE INITIALLY OR ONLY SLOWLY LIFT NORTH...SO SEVERE WX THREAT TUES NIGHT REMAIN UNCLEAR...BUT WILL LIKELY BE MAINLY ACROSS PIEDMONT INITIALLY. HEAVY RAIN WITH SOUTHEAST UPSLOPE AND LIFT OVER WEDGE IS LIKELY A BIGGER ISSUE OVERALL...WITH ONE TO TWO INCHES LOCALLY...ESPECIALLY NEAR BLUE RIDGE. SOME INDICATIONS ANOTHER BAND OF STORMS COULD THEN MOVE IN VERY EARLY WED MORNING...BUT 12Z MODELS HAVE BACKED OFF A LITTLE ON THAT IDEA...WITH MORE LIKELY TIMING BEING MIDDAY TO AFTERNOON AHEAD OF COLD FRONT. STRONG SSW FLOW JUST ABOVE STABLE LAYER EARLY WED MORNING...COMBINED WITH ANY HEAVIER RAIN BANDS...LIKELY TO MIX SHALLOW WEDGE OUT BY DAYBREAK WEDNESDAY. STORMS THAT DEVELOP AHEAD OF COLD FRONT THEN WILL BE DEVELOPING IN UNSTABLE SFC-BASED AIRMASS..WITH FAIRLY STRONG LOW LEVEL SHEAR. GETTING MORE CONCERNED ABOUT SEVERE WEATHER POTENTIAL FOR ENTIRE CWA...BUT ESPECIALLY IN PIEDMONT WITH DIURNAL INCREASE IN INSTABILITY BY AFTERNOON. WINDS...HAIL...BUT THIS WOULD BE HIGHEST CHANCE FOR ANY ISOLATED TORNADOES IN OUR AREA THIS WEEK. WILL NEED TO KEEP A CLOSE EYE ON THIS DEVELOPMENT AND TIMING...AND COMBINED WITH ONGOING FLASH FLOOD THREAT AND THEN EVENTUALLY RIVER FLOOD THREAT (SEE HYDROLOGY SECTION BELOW)...COULD BE A VERY BUSY DAY. TUESDAY NIGHT TEMPS COULD WARM IN SOME LOCATIONS AS WEDGE BREAKS..BUT AT THIS POINT THIS LEVEL OF DETAIL IS HARD TO DEPICT WITH LOW CONFIDENCE IN JUST HOW SOON THIS MAY HAPPEN. COULD BE CLOSE TO MORNING. MODELS A LITTLE FASTER KICKING STORMS EAST BY LATE WED EVENING...WITH SOME LINGERING LIGHT SHOWERS IN WESTERN SLOPES OF APPALACHIANS LINGERING INTO THURSDAY...BUT NOTICEABLY COOLER AIR A LITTLE DELAYED UNTIL THURS NIGHT. STILL MILD TEMPERATURES FOR THE DAYTIME THURSDAY. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 1PM EDT MONDAY... 12Z GFS COMING INTO LINE WITH THE EURO FOR THE EXTENDED SO CONFIDENCE IS GROWING IN THE FORECAST. EXPECTING PATTERN TO MIGRATE FROM A CLOSED LOW OVER THE MIDSECTION OF THE COUNTRY TO A SLOW MOVING BROAD TROF WITH THE CLOSED LOW CENTER RECONFIGURING FURTHER NORTH. THIS WILL ALLOW THE TROF AXIS TO FINALLY MOVE TO OUR EAST LATE SATURDAY...FOLLOWED BY A BROAD FLAT HIGH BUILDING WITH NW FLOW ALOFT INTO NEXT WEEK. FRIDAY LOOKS TO BE MOSTLY DRY WITH A CHC FOR SOME UPSLOPE SHOWERS WEST OF THE BLUE RIDGE. SATURDAY WILL FEATURE A HIGHER CHC OF UPSLOPE SHOWERS AS THE SHORT WAVE KICKER ROTATES AROUND THE BASE OF THE UPPER TROF AND A COLD FRONT SURGES THROUGH THE AREA. MAY SEE SOME SHOWER ACTIVITY CARRY OUT INTO THE PIEDMONT GIVEN THE INSTABILITY IN THE COLD POOL...BUT WILL NOT MENTION ANY THUNDER ACROSS THE FORECAST AREA ATTM. HIGH PRESSURE BUILDS IN FOR SUNDAY MORNING AND IT LOOKS LIKE DECENT RAD COOLING CONDITIONS. THERE MAY BE SOME FROST OR FREEZE CONCERNS TO CONSIDER WEST OF THE BLUE RIDGE SINCE THE LETHARGIC GROWING SEASON WILL HOPEFULLY BE UNDERWAY BY THEN. AS WE HEAD INTO NEXT WEEK...WE WILL WIND UP WITH A FRONTAL BOUNDARY DRAPED OVER US WHICH SHOULD KEEP PCPN IN THE FORECAST MON AND TUE. BELIEVE THERE IS THE POTENTIAL FOR CONVECTION TO RIDE ALONG THIS BOUNDARY AND AFFECT THE AREA BUT DETAILS ARE SKETCHY AT BEST AND WILL NOT ATTEMPT TO GET FANCY THAT FAR OUT. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 740 PM EDT MONDAY... NOT MUCH CHANGE TO THE AVIATION FORECAST...AS WEDGE WILL HOLD CIGS AND SOME VSBYS DOWN AT ALL TAF SITES. EXCEPTION AT TIMES WILL BE BLF WHICH HANGS RIGHT ALONG THE WEDGE FRONT. EARLY THIS EVENING SHOWERS SOME HEAVY MOVE ACROSS DAN/LYH BEFORE EXITING. KEEPING A BREAK IN THE RAIN WITH MAINLY DRIZZLE AND/OR FOG. NEXT ROUND ARRIVES AFTER 05Z-07Z...WITH THE HEAVIER SHOWERS ARRIVING TUE AFTERNOON. OVERALL NOT SEEING ANYTHING IMPROVING ABOVE MVFR THIS TAF PERIOD. WINDS WILL BE MAINLY OUT OF THE NE-SE. SOME STRONGER WINDS MAY IMPACT BLF AHEAD OF THE NEXT WAVE...BUT CONFIDENCE IS LOW TO INCREASE MORE THAN 10-12 KNOTS. BANDS OF HEAVIER SHOWERS AND POSSIBLE THUNDERSTORMS CONTINUE INTO TUESDAY EVENING. A DEEP AREA OF LOW PRESSURE ALOFT SLOWLY DRIFTS INTO THE REGION FROM THE WEST. SUB VFR CONDITIONS CAN BE EXPECTED AGAIN ON WEDNESDAY WITH BANDS OF SHRA/TSRA. APPEARS ENOUGH DRYING ALOFT TO PERHAPS SEE IMPROVEMENT TO VFR ACROSS THE EAST LATER THURSDAY INTO FRIDAY WITH MVFR LIKELY LINGERING AT TIMES ACROSS THE SE WEST VA LOCATIONS INTO FRIDAY. A WEAK LOW PRESSURE SYSTEM WILL CROSS THE TENNESSEE VALLEY ON SATURDAY WITH A CHANCE OF PRECIPITATION AND MVFR CONDITIONS IN THE MOUNTAINS. && .HYDROLOGY... AS OF 300 PM EDT MONDAY... PATTERN SETTING UP WITH SOME IMPRESSIVE STRONG SIGNALS FOR A PROLONGED PERIOD OF RAINFALL WITH HEAVY RAIN AMOUNTS BECOMING MORE LIKELY...ESPECIALLY TUESDAY INTO WEDNESDAY. THIS IS JUST THE BEGINNING OF PROLONGED HEAVY RAINFALL. THE RAIN FROM MONDAY AND TONIGHT WILL MOISTEN THE GROUND. ADDITIONAL RAINFALL WILL INCREASE THE PROBABILITY OF FLASH FLOODING. THE MORE RAIN...THE HIGHER THE THREAT. WITH WIDESPREAD TWO TO FOUR INCHES OF RAINFALL EXPECTED BY THURSDAY MORNING ACROSS THE FORECAST AREA...A FLASH FLOOD WATCH HAS BEEN ISSUED FOR THE ENTIRE COUNTY WARNING AREA. THERE IS AN INCREASING CHANCE FOR MAINSTEM RIVER FLOODING BY MID TO LATE THIS WEEK. BUT STILL TOO EARLY FOR HIGH CONFIDENCE IN WHICH RIVERS AND HOW WIDESPREAD FLOODING WILL BE. STAY TUNED. LATEST RUNS OF ENSEMBLE MODEL FORECAST FROM THE GEFS AND THE NAEFS WERE SUGGESTING AN INCREASING PROBABILITY OF MODERATE RIVER FLOODING ON THE DAN RIVER AT SOUTH BOSTON AND ON THE ROANOKE AT RANDOLPH. FLOODING POSSIBILITIES ARE ALSO INDICATED FOR PARTS OF THE JAMES AND GREENBRIER RIVER BASINS. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR VAZ007-009>018-022-032-033. FLASH FLOOD WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY EVENING FOR VAZ019-020-023-024-034-035-043>047-058-059. NC...FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR NCZ001>003-018>020. FLASH FLOOD WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY EVENING FOR NCZ004>006. WV...FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR WVZ042>045. && $$ SYNOPSIS...JH/SK NEAR TERM...AMS/WP SHORT TERM...SK LONG TERM...MBS AVIATION...AMS/JH/WP HYDROLOGY...AMS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
241 PM PDT SUN APR 27 2014 .SYNOPSIS...COOL AND SHOWERY WEATHER BEHIND A COLD FRONT TODAY. AN UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS THROUGH THE EARLY EVENING. A WARM FRONT MAY BRUSH THE FORECAST AREA WITH SOME RAIN MONDAY NIGHT. A CHANGE TO DRIER AND MUCH WARMER WEATHER TUESDAY THROUGH THE REST OF THE WEEK AS HIGH PRESSURE MOVES IN AND OFFSHORE WINDS DEVELOP. TEMPERATURES SHOULD PEAK IN THE 70S ON TUESDAY AND THE 80S WEDNESDAY AND THURSDAY. THE WINDS WILL TURN ONSHORE FRIDAY FOR SLIGHT COOLING...BUT STILL UNSEASONABLY WARM WEATHER. && .SHORT TERM...TONIGHT THROUGH WEDNESDAY...SHOWERS CONTINUE THIS AFTERNOON AS THE SECOND UPPER LEVEL SHORT WAVE TROUGH MOVES OVER NW OREGON. COLDER AIR ASSOCIATED WITH THE UPPER TROUGH COMBINED WITH WARMER AIR NEAR THE SURFACE...HAS RESULTED IN ENOUGH ATMOSPHERIC INSTABILITY TO SUPPORT A FEW THUNDERSTORMS ACROSS THE AREA. WE HAVE RECEIVED REPORTS OF LIGHTNING...THUNDER AND SMALL HAIL FROM THE COAST TO THE CASCADE FOOTHILLS...THOUGH ISOLATED IN NATURE. THE THREAT FOR THUNDERSTORMS WILL CONTINUE THROUGH LATE THIS AFTERNOON. AN UPPER RIDGE WILL PUSH THE SHORTWAVE NE OF THE REGION THIS EVENING...AND SHOWERS WILL DIMINISH. SNOW LEVELS ARE AROUND 3500 TO 4000 FEET AND WEB CAMERAS ARE SHOWING SNOW COVERING THE ROADS AT MANY OF THE CASCADE PASSES. SNOW RATES HAVE MAINTAINED BELOW ADVISORY CRITERIA FOR ELEVATIONS BELOW 5000 FEET...BUT EXPECT OVER A FOOT OF SNOW AT ABOVE 5000 FEET BY THE END OF TONIGHT. WITH LINGERING SURFACE MOISTURE...LIGHT WINDS...AND CLEARING LATE TONIGHT EXPECT SOME PATCHY FOG AND LOW CLOUDS FOR THE INTERIOR VALLEYS EARLY MONDAY MORNING. DESPITE ANY LOW CLOUDS...TEMPERATURES SHOULD WARM TO NEAR NORMAL TEMPERATURES IN THE AFTERNOON...WITH HIGHS IN THE LOWER 60S FOR THE INLAND VALLEYS AND UPPER 50S FOR THE COAST. SNOW LEVELS WILL RISE UP TO AROUND 6000 FEET BEFORE A WEAK WARM FRONT BRINGS A CHANCE FOR LIGHT RAIN MONDAY NIGHT. THE MODELS STILL VARY ON THE INLAND EXTENT OF THE RAIN WITH ECMWF THE DRIEST AND GFS AND NAM FORECASTING LIGHT QPF ACROSS NW OREGON. STILL THINK THERE IS A POSSIBILITY OF MEASURABLE RAIN MONDAY NIGHT AND HAVE LEFT THE LOW-END CHANCE POPS. HIGH PRESSURE WILL BUILD TUESDAY AND BEGIN A WARMING TREND FOR THE PACIFIC NW. TEMPERATURES WILL WARM TO AROUND 5 DEGREES ABOVE NORMAL FOR THE COAST AND 10 DEGREES ABOVE NORMAL FOR THE INTERIOR VALLEYS. OFFSHORE WINDS WILL DEVELOP TUESDAY NIGHT AND SET THE STAGE FOR A EVEN WARMER DAY ON WEDNESDAY.WEDNESDAY IS EXPECTED TO BE THE WARMEST DAY OF THE YEAR SO FAR. MODELED 850 MB TEMPERATURES ARE AROUND 15C UNDER A 582 DAM 500 MB RIDGE. A THERMAL TROUGH ALONG THE COAST WILL SUPPORT OFFSHORE WINDS...CLEAR SKIES...AND WARMING FOR THE COAST. EXPECT INLAND TEMPERATURES IN THE LOW TO MID 80S AND COASTAL TEMPERATURES IN THE UPPER 70S. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...NOT MUCH CHANGE IN FCST THINKING FOR THE EXTENDED PERIOD TODAY. A STRONG UPPER LEVEL TROF WILL REMAIN IN PLACE OVER THE SECOND HALF OF THE WEEK...WITH DRY AND SIGNIFICANTLY WARMER THAN AVERAGE WEATHER. THE LATEST RUNS OF THE MEDIUM RANGE MODELS CONTINUE TO INDICATE THAT THE OFFSHORE THERMALLY INDUCED SURFACE TROF WILL MOVE ONSHORE THU. THU CONTINUES TO LOOK LIKE THE WARMEST DAY OF THE WEEK...EXCEPT AT THE COAST WHERE SOME LIGHT ONSHORE FLOW MIGHT COOL THINGS OFF A BIT. FOR THE INTERIOR LOWLANDS...WILL KEEP MID 80S IN THE FCST FOR HIGHS . THEN THE THERMAL TROF MOVES OFF TO THE EAST ON FRI...WITH INCREASING ONSHORE FLOW BEGINNING THE COOLING PROCESS. THE HIGH TEMPS FRI WILL LIKELY STILL BE WELL ABOVE NORMAL...BUT SHOULD FALL SEVERAL DEGREES SHORT OF THU. AS THE UPPER LEVEL RIDGE BEGINS TO FLATTEN AND MOVE E NEXT WEEKEND...TEMPS SHOULD RETURN CLOSER TO NORMAL. THERE IS QUITE A BIT OF UNCERTAINTY IN THE MODELS DURING THIS TIME PERIOD...BUT IT APPEARS THAT AN UPPER LEVEL LOW MAY BRING SOME LIGHT RAIN CHANCES AT SOME POINT NEXT WEEKEND. PYLE && .AVIATION...COOL MOIST W FLOW ALOFT...WITH SCATTERED SHOWERS AND ISOLATED TSTMS. OVERALL...VFR CONDITIONS BUT EXPECT BRIEF MVFR UNDER THE SHOWERS INTO THIS EVENING. SOME SHOWERS WILL HAVE SMALL HAIL. WILL ALSO MAINTAIN THREAT OF VERY ISOLATED TSTMS UNTIL 03Z. SHOWERS WILL DECREASE AFTER 03Z...THEN SOME CLEARING. WILL SEE PATCHY FOG/LOW STRATUS BETWEEN 12Z AND 18Z...MAINLY OVER INTERIOR LOWLANDS. OTHERWISE INCREASING MID/HIGH CLOUDS MON AM AS WEAK WARM FRONT APPROACHES. KPDX AND APPROACHES...VFR CONTINUES...WITH OCCASIONAL SHOWERS. WITH BRIEF MVFR CIGS/VIS UNTIL 03Z...THEN SHOWERS DECREASING AND CLOUDS BREAKING UP. AS AIR MASS STABILIZES OVERNIGHT..MAY HAVE PATCHY FOG OR LOW STRATUS AFTER 12Z. ROCKEY && .MARINE...COOL UNSTABLE AIR MASS WITH SHOWERS OVER THE REGION TODAY AND TONIGHT. THOUGH PRES GRADIENTS HAVE RELAXED...WILL STILL HAVE SOME GUSTS TO 25 KT UNDER THE SHOWERS INTO EARLY THIS EVENING. SEAS GENERALLY HOLDING AT 9 TO 10 FT. A WEAK WARM FRONT WILL LIFT N ACROSS THE COASTAL WATERS LATE MON AND MON NIGHT...WITH GUSTS 20 TO 25 KT...MAINLY 10 NM AND FURTHER OFFSHORE. AFTERWARDS...HIGH PRES BUILDS WITH A THERMAL TROUGH BUILDING ALONG THE COAST. THIS WILL BRING QUIET WEATHER FOR WED THROUGH SAT. ROCKEY. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY TONIGHT AND MON ON ALL COASTAL WATERS. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS UNTIL 7 PM TODAY...AND AGAIN 3 AM TO 8 AM MON. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA..
Area Forecast Discussion National Weather Service Spokane WA 224 PM PDT SUN APR 27 2014 .SYNOPSIS... Cool and showery weather will linger into Monday but overall will be not as widespread as the wet weather that occurred over the weekend. Much drier and warmer weather will develop Tuesday through Friday as strong high pressure builds over the region. Warm weather is expected to peak Thursday and Friday with high temperatures 10 to 15 degrees above average. High pressure is expected to gradually break down next weekend ushering in a cooling trend. && .DISCUSSION... Tonight and Monday...An upper level trough will remain over Central and Eastern Washington into North Idaho this evening before moving into Montana on Monday. For this evening the atmosphere will remain moist and unstable over the northern mountains, the eastern third of Washington into the Idaho Panhandle. Models show uncapped CAPE values of 300-600 J/KG with the best instability over the Okanogan Highlands, Northeast Washington Mountains, Spokane area, and Palouse where sunbreaks have helped destabilize the atmosphere. Isolated thunderstorms are expected through early this evening in these areas with small hail or graupel expected with these storms. Across North Central Washington strong downslope flow off the Cascades should result in dry conditions for Wenatchee and Moses Lake. Showers will decrease across the region after sunset with the loss of daytime heating but will persist over the Central Panhandle Mountains and possibly the Camas Prairie during the overnight hours with moist, unstable northwest flow. On Monday the mid levels of the atmosphere will warm as the trough moves east of the region. However models show shallow convection developing over the higher terrain of the northern mountains and Idaho Panhandle during the afternoon. Elsewhere dry conditions are likely on Monday as the beginning of a warming trend takes place. JW Monday night through Wednesday...High pressure will build in from the west Monday night and strengthen through the week. This will result in a warming and drying trend. A few showers will linger across the the central and north Idaho Panhandle mountains Monday evening. And a weak disturbance is expected to move into the ridge on Monday night but will get sheared apart. The effect on sensible weather will be some variable high clouds over the Cascade. Otherwise look for warm sunny days and clear cool nights. Temperatures on Tuesday will warm into the 60s and low 70s and on Wednesday mainly lowers 70s. The temperatures Wednesday will be 5-10 degrees warmer than seasonal normals. Winds will be mainly light and diurnally driven. /Tobin Thursday: Warm and dry weather will continue for at least one more day. The high amplitude ridge still remains quite stout, with lots of sun and temperatures in the 70s common. Upper 70s and lower 80s will also be possible over the deep Columbia Basin. Friday through Sunday night: While Friday will still be mostly warm and dry, there are signs that the ridge will begin to break down and some more unsettled weather will return once again. There are a couple main players that will affect what happens in the far extended portion of the forecast. One is a well-defined low pressure that will move east toward the Pacific Northwest. The other is a weather disturbance that rotates south around a Hudson Bay low trough. The break-down of the ridge will depend on how far east the Pacific low pressure gets and/or how far west the Hudson Bay short-wave is located. The latest runs of the extended models are in decent agreement (finally) that both will move close enough to the Inland Northwest that the ridge will be pushed sufficiently far enough south and east to open up at least some chances for precipitation. Have gone ahead and nudged chances up further for the weekend into early the following week. Right now it looks like the best chances will be over the higher terrain of northeast Washington and the northern/central Idaho Panhandle. And finally, while the ridge break-down is agreed upon by the models, the resulting end location of the Pacific cut-off low pressure is still in question. Went with the status-quo for now with plenty of time (and nice weather) to look into this. As far as temperatures go, a general decrease in temperatures will occur each day beginning Friday, with more normal early May temperatures expected by late in the weekend. ty && .AVIATION... 18Z TAFS: An unstable air mass associated with an upper level trough will promote cumulus buildups through the afternoon with scattered showers and isolated thunderstorms. Downslope flow off the Cascades will result in most of this activity over the eastern third of Washington into the Idaho Panhandle. Meanwhile tightening pressure gradient and good afternoon mixing over Central Washington extending into Spokane and Pullman will result in breezy winds mainly during the afternoon. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 32 54 35 63 39 71 / 20 10 0 0 0 0 Coeur d`Alene 31 53 31 62 37 70 / 40 20 10 0 0 0 Pullman 31 52 32 61 38 69 / 50 10 10 0 0 0 Lewiston 37 58 37 67 42 75 / 20 10 10 0 0 0 Colville 31 60 32 69 37 75 / 50 10 10 0 0 0 Sandpoint 32 50 29 63 36 69 / 60 20 10 0 0 0 Kellogg 33 49 32 62 38 68 / 70 30 10 0 0 0 Moses Lake 33 63 37 69 42 77 / 10 0 0 0 0 0 Wenatchee 40 64 42 71 46 75 / 10 0 0 0 0 0 Omak 32 62 32 70 40 74 / 10 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 1044 AM PDT SUN APR 27 2014 .SYNOPSIS... Widespread rain showers are expected today over north Idaho and eastern Washington. The showery weather today will be accompanied by cooler than average temperatures and breezy conditions this afternoon. Drier and warmer weather will develop on Tuesday, and much above average temperatures are expected Wednesday through at least Friday. && .DISCUSSION... A strong upper level wave over Northeast Washington will move into North Idaho this morning into the early afternoon bringing widespread showers. A combination of moderate precipitation intensity...and wet bulb cooling has allowed snow levels to drop as low as 1500-2000 feet over Pend Oreille and Stevens counties with a report of 1.6" of snow near Clayton, with accumulations also reported in Newport and on Loon Lake Summit. As temperatures warm through the morning this snow will change to a rain/snow mix in the valleys and thus the window for additional accumulations is narrow and by 9-10 am most of what has fallen should begin to melt as temperatures rise above freezing. However in the mountains snow will continue with as much as 2-3 inches possible. Meanwhile behind this wave downslope flow has developed in the lee of the Cascades and thus have removed the chance of showers for the morning in Wenatchee. For this afternoon the atmosphere will destabilize with a 500mb cold pool of -32C over the area. SPC Calibrated thunder chances show the best chances for thunderstorms over the eastern third of Washington where a combination of afternoon sun breaks and lingering low level moisture will result in the highest CAPE values ranging from 300-600 J/KG. Over North Central Washington as the lower levels continue to dry due to downslope off the Cascades cloud bases will rise to where any developing cumulus clouds will be composed of mainly ice crystals with the needed charge separation for thunder unlikely. The HRRR also shows less intensity to the showers in these areas for the afternoon. Thus have removed the slight chance of thunderstorms through the evening for the Methow and Okanogan Valleys. JW && .AVIATION... 18Z TAFS: An unstable air mass associated with an upper level trough will promote cumulus buildups through the afternoon with scattered showers and isolated thunderstorms. Downslope flow off the Cascades will result in most of this activity over the eastern third of Washington into the Idaho Panhandle. Meanwhile tightening pressure gradient and good afternoon mixing over Central Washington extending into Spokane and Pullman will result in breezy winds mainly during the afternoon. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 50 32 54 36 63 40 / 70 20 10 0 0 0 Coeur d`Alene 49 29 53 33 63 35 / 90 60 20 0 0 0 Pullman 50 32 52 33 62 37 / 90 50 20 0 0 0 Lewiston 56 32 58 38 68 41 / 60 20 10 0 0 0 Colville 55 26 60 35 68 38 / 80 50 10 0 0 0 Sandpoint 46 29 50 32 61 34 / 90 60 20 10 0 0 Kellogg 45 29 49 34 61 40 / 90 90 30 10 0 0 Moses Lake 60 34 63 39 68 40 / 20 10 10 0 0 0 Wenatchee 58 35 64 44 69 45 / 20 10 10 0 0 0 Omak 58 30 62 35 68 38 / 30 10 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
838 AM PDT SUN APR 27 2014 .SYNOPSIS...COOL AND SHOWERY WEATHER BEHIND A COLD FRONT TODAY. AN UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS THROUGH THIS EVENING. A WARM FRONT MAY BRUSH THE FORECAST AREA WITH SOME RAIN MONDAY...BUT A CHANGE TO DRIER AND MUCH WARMER WEATHER WILL FOLLOW IT. TUESDAY WILL BE DRY WITH INLAND TEMPERATURES WARMING INTO THE THE 70S. OFFSHORE FLOW WILL ALLOW COASTAL TEMPERATURES TO WARM INTO THE 70S ON WEDNESDAY WITH LOW 80S FOR THE INLAND VALLEYS. ANOTHER WARM DAY EXPECTED THURSDAY BEFORE ONSHORE WINDS BRINGS SLIGHT COOLING FOR FRIDAY. && .UPDATE...TODAY THROUGH TUESDAY SHOWERS ARE COMING IN WITH EARNEST THIS MORNING AS AN UPPER LEVEL SHORTWAVE TROUGH MOVES OVER THE AREA. WATER VAPOR IMAGERY SHOWS ANOTHER SHORTWAVE OFFSHORE THAT WILL KEEP SHOWERS GOING THROUGH THE AFTERNOON. COLD AIR ALOFT WILL INCREASE INSTABILITY ADDING TO THE CONVECTIVE NATURE OF THESE SHOWERS.SMALL HAIL MAY ACCOMPANY SOME OF THE HEAVIER SHOWERS...AND THERE MAY EVEN BE A STRAY LIGHTNING STRIKE...MAINLY TO THE NORTH LATER THIS MORNING AND AFTERNOON. SNOW LEVELS ARE CURRENTLY AROUND 3500 TO 4000 FEET...SO THE CASCADES WILL KEEP GETTING NEW SNOW...THOUGH RATES DO NOT LOOK TO BE HEAVY AT ANY ONE TIME AND ENOUGH TO GET TO 6" OTHER THAN UP AT THE HIGHEST CASCADE ELEVATIONS. BY TONIGHT THE UPPER JET WILL BE LIFTING NORTH...AND AS THIS OCCURS SURFACE HIGH PRESSURE BECOMES FIRMLY IN CONTROL AND WILL WIDDLE DOWN THE SHOWERS SIGNIFICANTLY. ENOUGH STABILIZATION IN THE LOW LEVELS MAY RESULT IN SOME FOG BY MONDAY MORNING. LATER MONDAY AND MONDAY NIGHT...THE INITIAL SIGNS OF OUR UPCOMING WEATHER PATTERN CHANGE BECOMES APPARENT AS UPPER LEVEL RIDGING BEGINS TO BUILD ALONG THE COAST. AS THIS AMPLIFICATION IS OCCURRING...UPSTREAM LOW PRESSURE CONTINUES TO DIG. IN THE SOUTHWEST FLOW AHEAD OF THIS LOW...A WARM FRONT WILL APPROACH THE REGION WITH A MODEST MOISTURE FEED OF 1+" PRECIPITABLE WATER. MODELS INDICATE LOW-LEVEL FRONTOGENESIS INITIALLY WITH THIS WARM FRONT...BUT ARE STRUGGLING WITH HOW THE STRENGTHENING RIDGE WILL INFLUENCE THE FRONTOGENESIS. THE NAM/GFS ARE A BIT MORE AGGRESSIVE WITH FRONTOGENESIS AND RAIN...WHEREAS THE ECMWF SHOWS THE FRONT WEAKENING CONSIDERABLY AND A MAINLY DRY FORECAST. THINK THERE WILL BE ENOUGH LOW-LEVEL MOISTURE TO SQUEEZE OUT SOME LIGHT RAIN AND MAINTAINED THE PREVIOUS FORECAST OF LOWER END CHANCE POPS FOR MONDAY NIGHT. HIGH PRESSURE WILL BUILD TUESDAY AND BEGIN A WARMING TREND FOR THE PACIFIC NW. TEMPERATURES ON TUESDAY ARE EXPECTED TO BE 5 DEGREES WARMER THAN NORMAL FOR THE COAST AND 10 DEGREES WARMER THAN NORMAL FOR THE INTERIOR VALLEY. OFFSHORE WINDS WILL DEVELOP TUESDAY NIGHT AND SET UP WEDNESDAY TO BE THE WARMEST DAY OF THE YEAR SO FAR. HARTLEY/KMD .LONG TERM...NO CHANGES...PREVIOUS DISCUSSION UNCHANGED...TUESDAY NIGHT THROUGH SATURDAY... A STRONG UPPER LEVEL RIDGE OVER THE PAC NW WILL BRING DRY AND VERY WARM WEATHER TO THE REGION ON WED AND THU. A THERMALLY INDUCED SURFACE TROUGH IS MODELED TO BRING EASTERLY WIND ON WED...AND MANY INTERIOR LOCATIONS WILL LIKELY BRING AFTERNOON HIGHS INTO THE LOW 80S. IT IS NOT OUT OF THE QUESTION THAT SOME COASTAL SPOTS MAY APPROACH 80 AS WELL. THE SURFACE THERMAL TROUGH LOOKS LIKE IT WILL MOVE ONSHORE THU...LIKELY ALLOWING SOME COOLING ONSHORE FLOW AT THE COAST. BUT DECIDED TO BUMP UP THE INTERIOR TEMPS SEVERAL DEGREES HIGHER THAN WED...WITH HIGHS INTO THE MID 80S. LOOKING AT AREA CLIMATE STATS...IT IS APPEARS POSSIBLE THAT WE MAY MAKE A RUN AT SETTING SOME DAILY MAX TEMP RECORDS ON WED AND THU. BY FRI...THE LATEST MODEL RUNS ARE MOVING THE UPPER LEVEL RIDGE FURTHER EAST...WITH THE SURFACE THERMAL TROF PUSHING EAST OF THE CASCADES. THIS WOULD INDICATE AN INCREASE IN COOLING ONSHORE FLOW. KEPT THE FCST TRENDING IN THIS DIRECTION...BUT INCREASED HIGH TEMPS A BIT AS IT SEEMS THAT THE MODELS ARE OFTEN TOO AGGRESSIVE COOLING THINGS OFF ON THE DAY THAT THE THERMAL TROF IS FCST TO MOVE EAST OF THE REGION. STARTED BRINGING SLIGHT CHANCES FOR PRECIP BACK FRI NIGHT INTO SAT AS AN UPPER LEVEL TROF STARTS TO PUSH IN TO REPLACE THE DEPARTING RIDGE. PYLE && .AVIATION...COOL MOIST W FLOW ALOFT...WITH SCATTERED SHOWERS. OVERALL...VFR CONDITIONS...BUT EXPECT BRIEF MVFR UNDER THE SHOWERS THROUGH THE DAY. SOME SHOWERS WILL HAVE SMALL HAIL. WILL ALSO MAINTAIN THREAT OF VERY ISOLATED TSTMS UNTIL 03Z. SHOWERS WILL DECREASE AFTER 03Z...WITH SOME CLEARING AT THAT TIME. LATER TONIGHT INTO EARLY MON...THE MORE STABLE CONDITIONS WILL BRING PATCHY FOG/LOW STRATUS...MAINLY OVER INTERIOR LOWLANDS. KPDX AND APPROACHES...VFR TODAY AND TONIGHT. HOWEVER...WILL HAVE OCCASIONAL SHOWERS...WITH BRIEF MVFR CIGS/VIS UNTIL 02Z. AFTER 02Z...SHOWERS DECREASING. ROCKEY && .MARINE...COOL UNSTABLE AIR MASS WITH SHOWERS OVER THE REGION TODAY AND TONIGHT. THOUGH PRES GRADIENTS HAVE RELAXED...WILL STILL HAVE SOME GUSTS TO 25 KT UNDER THE SHOWERS TODAY. SEAS GENERALLY HOLDING AT 9 TO 10 FT. HIGH PRES BUILD OVER THE WATERS THROUGH MON. MODELS CONTINUE TO ROTATE A WARM FRONT ACROSS WATERS LATE MON THIS MAY BRING PERIOD OF S TO SE WINDS OF 20 TO 25 KT...MAINLY OVER THE OUTER WATERS. HIGH PRES BUILDS TUE WITH A THERMAL TROUGH BUILDING ALONG THE COAST WILL BRING QUIET WEATHER FOR WED THROUGH FRI. ROCKEY. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS THROUGH MON AFTERNOON ON ALL COASTAL WATERS. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS FROM 2 PM TO 7 PM TODAY. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA..
Area Forecast Discussion National Weather Service Spokane WA 816 AM PDT SUN APR 27 2014 .SYNOPSIS... Widespread rain showers are expected today over north Idaho and eastern Washington. The showery weather today will be accompanied by cooler than average temperatures and breezy conditions this afternoon. Drier and warmer weather will develop on Tuesday, and much above average temperatures are expected Wednesday through at least Friday. && .DISCUSSION... A strong upper level wave over Northeast Washington will move into North Idaho this morning into the early afternoon bringing widespread showers. A combination of moderate precipitation intensity...and wet bulb cooling has allowed snow levels to drop as low as 1500-2000 feet over Pend Oreille and Stevens counties with a report of 1.6" of snow near Clayton, with accumulations also reported in Newport and on Loon Lake Summit. As temperatures warm through the morning this snow will change to a rain/snow mix in the valleys and thus the window for additional accumulations is narrow and by 9-10 am most of what has fallen should begin to melt as temperatures rise above freezing. However in the mountains snow will continue with as much as 2-3 inches possible. Meanwhile behind this wave downslope flow has developed in the lee of the Cascades and thus have removed the chance of showers for the morning in Wenatchee. For this afternoon the atmosphere will destabilize with a 500mb cold pool of -32C over the area. SPC Calibrated thunder chances show the best chances for thunderstorms over the eastern third of Washington where a combination of afternoon sun breaks and lingering low level moisture will result in the highest CAPE values ranging from 300-600 J/KG. Over North Central Washington as the lower levels continue to dry due to downslope off the Cascades cloud bases will rise to where any developing cumulus clouds will be composed of mainly ice crystals with the needed charge separation for thunder unlikely. The HRRR also shows less intensity to the showers in these areas for the afternoon. Thus have removed the slight chance of thunderstorms through the evening for the Methow and Okanogan Valleys. JW && .AVIATION... 12Z TAFS: An occluded front will continue to slowly push across the region this morning spreading precipitation from southwest to northeast across the aviation area. Some snow may mix in with the rain at times and briefly accumulate above 2100 feet this morning. The atmosphere will destabilize in the afternoon and evening and may allow a few weak pulse thunderstorms to occur. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 50 32 54 36 63 40 / 80 20 10 0 0 0 Coeur d`Alene 50 29 53 33 63 35 / 90 60 20 0 0 0 Pullman 50 32 52 33 62 37 / 90 50 20 0 0 0 Lewiston 56 32 58 38 68 41 / 60 20 10 0 0 0 Colville 55 26 60 35 68 38 / 80 50 10 0 0 0 Sandpoint 48 29 50 32 61 34 / 90 60 20 10 0 0 Kellogg 46 29 49 34 61 40 / 90 90 30 10 0 0 Moses Lake 60 34 63 39 68 40 / 20 10 10 0 0 0 Wenatchee 58 35 64 44 69 45 / 20 10 10 0 0 0 Omak 58 30 62 35 68 38 / 30 10 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1052 PM CDT MON APR 28 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 957 PM CDT MON APR 28 2014 SURFACE DATA THIS EVENING SHOWING SOME VERY DRY AIR HAS SETTLED OVER FAR NORTHERN WISCONSIN AS A BAND OF RAIN LIFTS NORTH OVER NORTHERN WISCONSIN. SURFACE DEWPOINTS IN THE MID TEENS OVER VILAS AND FLORENCE COUNTIES WHILE DEWPOINTS WERE IN THE 30S OVER RHI. TEMPS RATHER MILD LATE THIS EVENING BUT ADDED A BRIEF MIX FAR NORTH DUE TO EVAP COOLING AFFECTS AS THIS BAND LIFTS NORTH. && .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 240 PM CDT MON APR 28 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A LARGE AND STUBBORN UPPER LOW SPINNING OVER THE CENTRAL GREAT PLAINS AND A WARM FRONT POSITIONED OVER CENTRAL IOWA TO CENTRAL INDIANA. WARM CONVEYOR BELT IS RISING OVER THE 850MB FRONT LOCATED OVER SOUTHERN WISCONSIN AND ALONG WITH MID-LEVEL FGEN...IS HELPING TO PRODUCE AN ARCING BAND OF RAIN FROM CENTRAL MINNESOTA TO CENTRAL LOWER MICHIGAN. THIS BAND HAS BEEN SLOWING LIFTING NORTH TODAY WITH ASSISTANCE FROM A SHORTWAVE LOBE OVER IOWA...WHICH IS ROTATING AROUND THE PARENT CYCLONE. THIS BAND WILL CONTINUE TO LIFT NORTH AND COULD REACH THE U.P BORDER BY THE END OF THE AFTERNOON. FAR NORTHERN WISCONSIN HAS BEEN DRY SO FAR TODAY WHERE TEMPS HAVE RISEN INTO THE LOWER 50S...BUT THIS SHOULD END SOON. PRECIP TRENDS AND AMOUNTS REMAIN THE MAIN FORECAST CONCERNS. TONIGHT...SLOW MOVING UPPER LOW OVER THE CENTRAL GREAT PLAINS WILL CONTINUE ITS SLOW JAUNT TO THE EAST. EAST OF THIS UPPER LOW...850MB WARM FRONT WILL LIFT NORTH INTO CENTRAL AND NORTHEAST WISCONSIN WHILE THE LEFT FRONT QUAD OF A JET STREAK WILL PUSH NORTHWARD ACROSS WISCONSIN. PLENTY OF MID-LEVEL FGEN AND UPPER DIVERGENCE WITHIN THE PWAT MAXIMUM BAND TO SUPPORT THE ARCING BAND OF RAIN OVER THE WESTERN GREAT LAKES TO LIFT SLOWLY NORTHWARD THROUGH THE NIGHT. A HALF INCH TO AN INCH OF RAIN IS POSSIBLE ACROSS CENTRAL AND EAST-CENTRAL WISCONSIN THAT WILL LIKELY AGGRAVATE RIVER FLOODING. AS THE PRECIP MOVES INTO NORTHERN WISCONSIN TONIGHT AND THE BOUNDARY LAYER COOLS...PROGGED SOUNDINGS LOOK COLD ENOUGH FOR WET SNOW FLAKES TO MIX IN WITH THE RAIN. PERHAPS COULD SEE A LITTLE COATING ON GRASSY SURFACES BUT TEMPS ARE EXPECTED TO REMAIN ABOVE FREEZING SO HARD TO SEE ANY ACCUMULATION ON ROADWAYS. WINDS WILL REMAIN GUSTY AND ACTUALLY INCREASE LATE TONIGHT OVER THE FOX VALLEY AS THE TRAJECTORIES TURN NORTHEAST AND FUNNEL DOWN THE BAY. WILL HAVE GUSTS UP TO 40 MPH LATE. LOWS IN THE MID TO UPPER 30S. TUESDAY...THE UPPER LOW WILL NOSE ITS WAY INTO THE SOUTHWESTERN GREAT LAKES. OTHERWISE...LITTLE CHANGES SYNOPTICALLY. WILL HAVE A STRONG SHORTWAVE ROTATE AROUND THE UPPER LOW INTO NORTHERN LAKE MICHIGAN DURING THE AFTERNOON WHICH WILL PUSH A 850MB TROUGH INTO NORTHEAST WISCONSIN. THIS MAY BRING BREAKS IN THE RAIN AND DIMINISHING WINDS OVER EAST-CENTRAL AND NORTHEAST WISCONSIN DURING THE PM HOURS...BUT EXPECT THE STEADY RAINS TO CONTINUE OVER NORTH-CENTRAL WISCONSIN THROUGH THE DAY. SOME RAIN WILL STILL HAVE SOME SNOW MIXED IN DURING THE MORNING HOURS. ANOTHER QUARTER TO A HALF INCH OF RAIN APPEARS POSSIBLE. HIGHS RANGING FROM AROUND 40 NORTH TO NEAR 50S SOUTH. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 240 PM CDT MON APR 28 2014 PCPN TRENDS AND TEMPERATURES ARE THE MAIN FCST CONCERNS. THE UPPER LEVEL LOW IS EXPECTED TO LINGER OVER THE WESTERN GREAT LAKES THROUGH THURSDAY...THEN WEAKEN INTO AN OPEN WAVE AND SHIFT EAST. THE MOST SIGNIFICANT BAND OF PCPN SHOULD ALREADY HAVE MOVED THROUGH THE CWA (MONDAY AFTERNOON THROUGH TUESDAY)...BUT A HIGH POP/LOW QPF SCENARIO IS LIKELY TO CONTINUE THROUGH THURSDAY. MODELS ARE ALL OVER THE PLACE WITH REGARD TO THE VARIOUS S/W TROFS ROTATING AROUND THE MAIN UPPER LOW...SO HAVE GONE WITH A MULTI- MODEL BLEND...RESULTING IN BROADBRUSH LIKELY POPS FROM TUES NGT THROUGH THURSDAY. PCPN SHOULD BE ALMOST ALL RAIN...BUT KEPT A MIX IN OVER VILAS CO LATE WED NGT/EARLY THU. THE UPPER AIR PATTERN IS EXPECTED TO GRADUALLY TRANSITION TO ZONAL FLOW BY THE END OF THE WEEKEND/EARLY NEXT WEEK...WITH OCNL S/W TROFS AND WEAK COLD FRONTS MOVING THROUGH. SMALL POPS ARE WARRANTED DURING THIS PERIOD...BUT PCPN AMOUNTS SHOULD BE ON THE LIGHT SIDE. THE AIR MASS WILL REMAIN COOL ENOUGH FOR A LIGHT MIX OF RAIN AND SNOW SHOWERS OVER NORTHERN WI DURING SOME OF THE NIGHTTIME PERIODS. TEMPERATURES WILL REMAIN BLO NORMAL THROUGH THE PERIOD...WITH HIGHS MAINLY IN THE UPPER 40S TO MIDDLE 50S...AND LOWS IN THE 30S AND LOWER 40S. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1051 PM CDT MON APR 28 2014 A LARGE UPPER LOW SYSTEM SLOWLY CHURNING ACROSS MID SECTION OF THE COUNTRY THIS WEEK WILL CONTINUE TO LIFT BANDS OF SHOWERS NORTH OVER THE STATE FOR MUCH OF THE WEEK. DRY AIR ON EASTERLY WINDS WILL CONTINUE TO FILTER INTO THE AREA TO KEEP CIGS MAINLY AT VFR LEVELS OVER FAR NORTHEAST WISCONSIN FOR A TIME TONIGHT. AS SHOWERS BECOME MORE WIDESPREAD FROM SOUTH TO NORTH OVERNIGHT INTO TUESDAY...CIGS WILL LOWER TO MVFR OR IFR LEVELS. COMPACT PRESSURE GRADIENT AHEAD OF THE LARGE SURFACE LOW OVER THE CENTRAL PLAINS WILL ENSURE GUSTY WINDS AT THE SURFACE FOR A FEW DAYS. && .HYDROLOGY... ISSUED AT 240 PM CDT MON APR 28 2014 RAINFALL TOTALS OF 1 TO 2 INCHES CAN BE EXPECTED BY WEDNESDAY AFTERNOON. THE HIGHEST TOTALS WILL BE ACROSS PORTIONS OF CENTRAL WISCONSIN INTO THE FOX VALLEY REGION. THE RESULTING RUNOFF COULD CAUSE SOME MINOR RIVER FLOODING...AS SEVERAL RIVERS STILL REMAIN ABOVE BANKFULL. WILL CONTINUE TO MENTION THE RIVER FLOODING THREAT IN A HYDROLOGIC OUTLOOK AND THE HAZARDOUS WEATHER OUTLOOK. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........TDH SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......TDH HYDROLOGY......MPC
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
958 PM CDT MON APR 28 2014 NEW INFORMATION ADDED TO UPDATE SECTION .UPDATE... ISSUED AT 957 PM CDT MON APR 28 2014 SURFACE DATA THIS EVENING SHOWING SOME VERY DRY AIR HAS SETTLED OVER FAR NORTHERN WISCONSIN AS A BAND OF RAIN LIFTS NORTH OVER NORTHERN WISCONSIN. SURFACE DEWPOINTS IN THE MID TEENS OVER VILAS AND FLORENCE COUNTIES WHILE DEWPOINTS WERE IN THE 30S OVER RHI. TEMPS RATHER MILD LATE THIS EVENING BUT ADDED A BRIEF MIX FAR NORTH DUE TO EVAP COOLING AFFECTS AS THIS BAND LIFTS NORTH. && .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 240 PM CDT MON APR 28 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A LARGE AND STUBBORN UPPER LOW SPINNING OVER THE CENTRAL GREAT PLAINS AND A WARM FRONT POSITIONED OVER CENTRAL IOWA TO CENTRAL INDIANA. WARM CONVEYOR BELT IS RISING OVER THE 850MB FRONT LOCATED OVER SOUTHERN WISCONSIN AND ALONG WITH MID-LEVEL FGEN...IS HELPING TO PRODUCE AN ARCING BAND OF RAIN FROM CENTRAL MINNESOTA TO CENTRAL LOWER MICHIGAN. THIS BAND HAS BEEN SLOWING LIFTING NORTH TODAY WITH ASSISTANCE FROM A SHORTWAVE LOBE OVER IOWA...WHICH IS ROTATING AROUND THE PARENT CYCLONE. THIS BAND WILL CONTINUE TO LIFT NORTH AND COULD REACH THE U.P BORDER BY THE END OF THE AFTERNOON. FAR NORTHERN WISCONSIN HAS BEEN DRY SO FAR TODAY WHERE TEMPS HAVE RISEN INTO THE LOWER 50S...BUT THIS SHOULD END SOON. PRECIP TRENDS AND AMOUNTS REMAIN THE MAIN FORECAST CONCERNS. TONIGHT...SLOW MOVING UPPER LOW OVER THE CENTRAL GREAT PLAINS WILL CONTINUE ITS SLOW JAUNT TO THE EAST. EAST OF THIS UPPER LOW...850MB WARM FRONT WILL LIFT NORTH INTO CENTRAL AND NORTHEAST WISCONSIN WHILE THE LEFT FRONT QUAD OF A JET STREAK WILL PUSH NORTHWARD ACROSS WISCONSIN. PLENTY OF MID-LEVEL FGEN AND UPPER DIVERGENCE WITHIN THE PWAT MAXIMUM BAND TO SUPPORT THE ARCING BAND OF RAIN OVER THE WESTERN GREAT LAKES TO LIFT SLOWLY NORTHWARD THROUGH THE NIGHT. A HALF INCH TO AN INCH OF RAIN IS POSSIBLE ACROSS CENTRAL AND EAST-CENTRAL WISCONSIN THAT WILL LIKELY AGGRAVATE RIVER FLOODING. AS THE PRECIP MOVES INTO NORTHERN WISCONSIN TONIGHT AND THE BOUNDARY LAYER COOLS...PROGGED SOUNDINGS LOOK COLD ENOUGH FOR WET SNOW FLAKES TO MIX IN WITH THE RAIN. PERHAPS COULD SEE A LITTLE COATING ON GRASSY SURFACES BUT TEMPS ARE EXPECTED TO REMAIN ABOVE FREEZING SO HARD TO SEE ANY ACCUMULATION ON ROADWAYS. WINDS WILL REMAIN GUSTY AND ACTUALLY INCREASE LATE TONIGHT OVER THE FOX VALLEY AS THE TRAJECTORIES TURN NORTHEAST AND FUNNEL DOWN THE BAY. WILL HAVE GUSTS UP TO 40 MPH LATE. LOWS IN THE MID TO UPPER 30S. TUESDAY...THE UPPER LOW WILL NOSE ITS WAY INTO THE SOUTHWESTERN GREAT LAKES. OTHERWISE...LITTLE CHANGES SYNOPTICALLY. WILL HAVE A STRONG SHORTWAVE ROTATE AROUND THE UPPER LOW INTO NORTHERN LAKE MICHIGAN DURING THE AFTERNOON WHICH WILL PUSH A 850MB TROUGH INTO NORTHEAST WISCONSIN. THIS MAY BRING BREAKS IN THE RAIN AND DIMINISHING WINDS OVER EAST-CENTRAL AND NORTHEAST WISCONSIN DURING THE PM HOURS...BUT EXPECT THE STEADY RAINS TO CONTINUE OVER NORTH-CENTRAL WISCONSIN THROUGH THE DAY. SOME RAIN WILL STILL HAVE SOME SNOW MIXED IN DURING THE MORNING HOURS. ANOTHER QUARTER TO A HALF INCH OF RAIN APPEARS POSSIBLE. HIGHS RANGING FROM AROUND 40 NORTH TO NEAR 50S SOUTH. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 240 PM CDT MON APR 28 2014 PCPN TRENDS AND TEMPERATURES ARE THE MAIN FCST CONCERNS. THE UPPER LEVEL LOW IS EXPECTED TO LINGER OVER THE WESTERN GREAT LAKES THROUGH THURSDAY...THEN WEAKEN INTO AN OPEN WAVE AND SHIFT EAST. THE MOST SIGNIFICANT BAND OF PCPN SHOULD ALREADY HAVE MOVED THROUGH THE CWA (MONDAY AFTERNOON THROUGH TUESDAY)...BUT A HIGH POP/LOW QPF SCENARIO IS LIKELY TO CONTINUE THROUGH THURSDAY. MODELS ARE ALL OVER THE PLACE WITH REGARD TO THE VARIOUS S/W TROFS ROTATING AROUND THE MAIN UPPER LOW...SO HAVE GONE WITH A MULTI- MODEL BLEND...RESULTING IN BROADBRUSH LIKELY POPS FROM TUES NGT THROUGH THURSDAY. PCPN SHOULD BE ALMOST ALL RAIN...BUT KEPT A MIX IN OVER VILAS CO LATE WED NGT/EARLY THU. THE UPPER AIR PATTERN IS EXPECTED TO GRADUALLY TRANSITION TO ZONAL FLOW BY THE END OF THE WEEKEND/EARLY NEXT WEEK...WITH OCNL S/W TROFS AND WEAK COLD FRONTS MOVING THROUGH. SMALL POPS ARE WARRANTED DURING THIS PERIOD...BUT PCPN AMOUNTS SHOULD BE ON THE LIGHT SIDE. THE AIR MASS WILL REMAIN COOL ENOUGH FOR A LIGHT MIX OF RAIN AND SNOW SHOWERS OVER NORTHERN WI DURING SOME OF THE NIGHTTIME PERIODS. TEMPERATURES WILL REMAIN BLO NORMAL THROUGH THE PERIOD...WITH HIGHS MAINLY IN THE UPPER 40S TO MIDDLE 50S...AND LOWS IN THE 30S AND LOWER 40S. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 643 PM CDT MON APR 28 2014 A LARGE UPPER LOW SYSTEM SLOWLY CHURNING ACROSS MID SECTION OF THE COUNTRY THIS WEEK WILL CONTINUE TO LIFT BANDS OF SHOWERS NORTH OVER THE STATE FOR MUCH OF THE WEEK. DRY AIR ON EASTERLY WINDS WILL CONTINUE TO POUR INTO THE AREA TO KEEP CIGS MAINLY AT VFR LEVELS OVER NORTHEAST WISCONSIN. AS SHOWERS BECOME MORE WIDESPREAD FROM SOUTHWEST TO NORTHEAST OVERNIGHT INTO TUESDAY...CIGS WILL LOWER TO MVFR OR IFR LEVELS. COMPACT PRESSURE GRADIENT AHEAD OF THE LARGE SURFACE LOW OVER THE CENTRAL PLAINS WILL ENSURE GUSTY WINDS AT THE SURFACE FOR A FEW DAYS. && .HYDROLOGY... ISSUED AT 240 PM CDT MON APR 28 2014 RAINFALL TOTALS OF 1 TO 2 INCHES CAN BE EXPECTED BY WEDNESDAY AFTERNOON. THE HIGHEST TOTALS WILL BE ACROSS PORTIONS OF CENTRAL WISCONSIN INTO THE FOX VALLEY REGION. THE RESULTING RUNOFF COULD CAUSE SOME MINOR RIVER FLOODING...AS SEVERAL RIVERS STILL REMAIN ABOVE BANKFULL. WILL CONTINUE TO MENTION THE RIVER FLOODING THREAT IN A HYDROLOGIC OUTLOOK AND THE HAZARDOUS WEATHER OUTLOOK. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........TDH SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......TDH HYDROLOGY......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
644 PM CDT MON APR 28 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 240 PM CDT MON APR 28 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A LARGE AND STUBBORN UPPER LOW SPINNING OVER THE CENTRAL GREAT PLAINS AND A WARM FRONT POSITIONED OVER CENTRAL IOWA TO CENTRAL INDIANA. WARM CONVEYOR BELT IS RISING OVER THE 850MB FRONT LOCATED OVER SOUTHERN WISCONSIN AND ALONG WITH MID-LEVEL FGEN...IS HELPING TO PRODUCE AN ARCING BAND OF RAIN FROM CENTRAL MINNESOTA TO CENTRAL LOWER MICHIGAN. THIS BAND HAS BEEN SLOWING LIFTING NORTH TODAY WITH ASSISTANCE FROM A SHORTWAVE LOBE OVER IOWA...WHICH IS ROTATING AROUND THE PARENT CYCLONE. THIS BAND WILL CONTINUE TO LIFT NORTH AND COULD REACH THE U.P BORDER BY THE END OF THE AFTERNOON. FAR NORTHERN WISCONSIN HAS BEEN DRY SO FAR TODAY WHERE TEMPS HAVE RISEN INTO THE LOWER 50S...BUT THIS SHOULD END SOON. PRECIP TRENDS AND AMOUNTS REMAIN THE MAIN FORECAST CONCERNS. TONIGHT...SLOW MOVING UPPER LOW OVER THE CENTRAL GREAT PLAINS WILL CONTINUE ITS SLOW JAUNT TO THE EAST. EAST OF THIS UPPER LOW...850MB WARM FRONT WILL LIFT NORTH INTO CENTRAL AND NORTHEAST WISCONSIN WHILE THE LEFT FRONT QUAD OF A JET STREAK WILL PUSH NORTHWARD ACROSS WISCONSIN. PLENTY OF MID-LEVEL FGEN AND UPPER DIVERGENCE WITHIN THE PWAT MAXIMUM BAND TO SUPPORT THE ARCING BAND OF RAIN OVER THE WESTERN GREAT LAKES TO LIFT SLOWLY NORTHWARD THROUGH THE NIGHT. A HALF INCH TO AN INCH OF RAIN IS POSSIBLE ACROSS CENTRAL AND EAST-CENTRAL WISCONSIN THAT WILL LIKELY AGGRAVATE RIVER FLOODING. AS THE PRECIP MOVES INTO NORTHERN WISCONSIN TONIGHT AND THE BOUNDARY LAYER COOLS...PROGGED SOUNDINGS LOOK COLD ENOUGH FOR WET SNOW FLAKES TO MIX IN WITH THE RAIN. PERHAPS COULD SEE A LITTLE COATING ON GRASSY SURFACES BUT TEMPS ARE EXPECTED TO REMAIN ABOVE FREEZING SO HARD TO SEE ANY ACCUMULATION ON ROADWAYS. WINDS WILL REMAIN GUSTY AND ACTUALLY INCREASE LATE TONIGHT OVER THE FOX VALLEY AS THE TRAJECTORIES TURN NORTHEAST AND FUNNEL DOWN THE BAY. WILL HAVE GUSTS UP TO 40 MPH LATE. LOWS IN THE MID TO UPPER 30S. TUESDAY...THE UPPER LOW WILL NOSE ITS WAY INTO THE SOUTHWESTERN GREAT LAKES. OTHERWISE...LITTLE CHANGES SYNOPTICALLY. WILL HAVE A STRONG SHORTWAVE ROTATE AROUND THE UPPER LOW INTO NORTHERN LAKE MICHIGAN DURING THE AFTERNOON WHICH WILL PUSH A 850MB TROUGH INTO NORTHEAST WISCONSIN. THIS MAY BRING BREAKS IN THE RAIN AND DIMINISHING WINDS OVER EAST-CENTRAL AND NORTHEAST WISCONSIN DURING THE PM HOURS...BUT EXPECT THE STEADY RAINS TO CONTINUE OVER NORTH-CENTRAL WISCONSIN THROUGH THE DAY. SOME RAIN WILL STILL HAVE SOME SNOW MIXED IN DURING THE MORNING HOURS. ANOTHER QUARTER TO A HALF INCH OF RAIN APPEARS POSSIBLE. HIGHS RANGING FROM AROUND 40 NORTH TO NEAR 50S SOUTH. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 240 PM CDT MON APR 28 2014 PCPN TRENDS AND TEMPERATURES ARE THE MAIN FCST CONCERNS. THE UPPER LEVEL LOW IS EXPECTED TO LINGER OVER THE WESTERN GREAT LAKES THROUGH THURSDAY...THEN WEAKEN INTO AN OPEN WAVE AND SHIFT EAST. THE MOST SIGNIFICANT BAND OF PCPN SHOULD ALREADY HAVE MOVED THROUGH THE CWA (MONDAY AFTERNOON THROUGH TUESDAY)...BUT A HIGH POP/LOW QPF SCENARIO IS LIKELY TO CONTINUE THROUGH THURSDAY. MODELS ARE ALL OVER THE PLACE WITH REGARD TO THE VARIOUS S/W TROFS ROTATING AROUND THE MAIN UPPER LOW...SO HAVE GONE WITH A MULTI- MODEL BLEND...RESULTING IN BROADBRUSH LIKELY POPS FROM TUES NGT THROUGH THURSDAY. PCPN SHOULD BE ALMOST ALL RAIN...BUT KEPT A MIX IN OVER VILAS CO LATE WED NGT/EARLY THU. THE UPPER AIR PATTERN IS EXPECTED TO GRADUALLY TRANSITION TO ZONAL FLOW BY THE END OF THE WEEKEND/EARLY NEXT WEEK...WITH OCNL S/W TROFS AND WEAK COLD FRONTS MOVING THROUGH. SMALL POPS ARE WARRANTED DURING THIS PERIOD...BUT PCPN AMOUNTS SHOULD BE ON THE LIGHT SIDE. THE AIR MASS WILL REMAIN COOL ENOUGH FOR A LIGHT MIX OF RAIN AND SNOW SHOWERS OVER NORTHERN WI DURING SOME OF THE NIGHTTIME PERIODS. TEMPERATURES WILL REMAIN BLO NORMAL THROUGH THE PERIOD...WITH HIGHS MAINLY IN THE UPPER 40S TO MIDDLE 50S...AND LOWS IN THE 30S AND LOWER 40S. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 643 PM CDT MON APR 28 2014 A LARGE UPPER LOW SYSTEM SLOWLY CHURNING ACROSS MID SECTION OF THE COUNTRY THIS WEEK WILL CONTINUE TO LIFT BANDS OF SHOWERS NORTH OVER THE STATE FOR MUCH OF THE WEEK. DRY AIR ON EASTERLY WINDS WILL CONTINUE TO POUR INTO THE AREA TO KEEP CIGS MAINLY AT VFR LEVELS OVER NORTHEAST WISCONSIN. AS SHOWERS BECOME MORE WIDESPREAD FROM SOUTHWEST TO NORTHEAST OVERNIGHT INTO TUESDAY...CIGS WILL LOWER TO MVFR OR IFR LEVELS. COMPACT PRESSURE GRADIENT AHEAD OF THE LARGE SURFACE LOW OVER THE CENTRAL PLAINS WILL ENSURE GUSTY WINDS AT THE SURFACE FOR A FEW DAYS. && .HYDROLOGY... ISSUED AT 240 PM CDT MON APR 28 2014 RAINFALL TOTALS OF 1 TO 2 INCHES CAN BE EXPECTED BY WEDNESDAY AFTERNOON. THE HIGHEST TOTALS WILL BE ACROSS PORTIONS OF CENTRAL WISCONSIN INTO THE FOX VALLEY REGION. THE RESULTING RUNOFF COULD CAUSE SOME MINOR RIVER FLOODING...AS SEVERAL RIVERS STILL REMAIN ABOVE BANKFULL. WILL CONTINUE TO MENTION THE RIVER FLOODING THREAT IN A HYDROLOGIC OUTLOOK AND THE HAZARDOUS WEATHER OUTLOOK. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......TDH HYDROLOGY......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
557 PM CDT SUN APR 27 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 238 PM CDT SUN APR 27 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW OCCLUDED LOW PRESSURE SPINNING OVER WESTERN KANSAS. A WARM FRONT EXTENDS FROM THIS LOW EASTWARD INTO THE OHIO VALLEY. NORTH OF THIS WARM FRONT...MID-LEVEL THETAE ADVECTION AND FGEN IS CONTRIBUTING TO A BAND OF LIGHT RAIN PROGRESSING NORTHWARD ACROSS THE FORECAST AREA THIS AFTERNOON. SHOWERS ARE TRYING TO REDEVELOP SOUTH OF THIS RAIN BAND OVER SOUTHWEST WISCONSIN...BUT COVERAGE IS SIGNIFICANTLY LESS OVER EASTERN IOWA AND NORTHERN ILLINOIS. THEN A POTENT LINE OF STORMS IS PROGRESSING NORTHEAST ACROSS IOWA AND MISSOURI. RAIN CHANCES AND AMOUNTS ARE THE MAIN FORECAST CONCERN IN THE SHORT TERM. TONIGHT...THE OCCLUDED CYCLONE OVER THE CENTRAL PLAINS WILL MOVE VERY LITTLE TO THE NORTHEAST FROM CENTRAL KANSAS TO NORTHEAST NEBRASKA WHILE HUDSON BAY HIGH PRESSURE REMAINS IN PLACE. ANTICIPATING THAT ARCING BAND OF RAIN ASSOCIATED WITH MID-LEVEL MOISTURE ADVECTION AND FGEN WILL HAVE WEAKENED AT THE START OF THE EVENING AS IT MOVES INTO A DRIER AIRMASS...BUT COULD STILL BE SOME SHOWERS HANGING ON ACROSS NORTHERN WISCONSIN AND WILL LEAVE A CHANCE IN THE FORECAST. THEN ANTICIPATE THAT THERE WILL BE A BREAK OR REDUCED COVERAGE OF PRECIP FOR A PERIOD THIS EVENING BEFORE THE LINE OF CONVECTION OVER THE PLAINS PIVOTS AS IT MOVES NE INTO WISCONSIN. THINK THIS LINE WILL MAKE IT INTO CENTRAL WISCONSIN AND THE SOUTHERN FOX VALLEY LATE TONIGHT (THOUGH WILL NOT BE NEARLY AS INTENSE AS IT STANDS CURRENTLY) DUE TO INCREASING 900-800MB MOISTURE TRANSPORT AND FGEN. PRIOR TO THIS AREA OF RAIN ARRIVING...CANNOT RULE OUT SPOTTY TO SCATTERED SHOWERS REDEVELOPING. BUT IN GENERAL...WILL HAVE THE LOWEST CHANCE OF PRECIP EARLY IN THE EVENING AND THEN GRADUALLY INCREASE CHANCES THROUGH THE NIGHT. LOWS SHOULD BE RELATIVELY STEADY IN THE MIDDLE TO UPPER 30S. MONDAY...THE ARCING BAND OF RAIN WILL SLOWLY LIFT NORTHEAST THROUGH THE DAY BUT SHOULD BE GRADUALLY WEAKENING AS IT DOES SO. SOME CONCERN THAT THE RAINS COULD BRING DOWN SOME BEEFY GUSTS FROM ALOFT AS THE NAM IS DEPICTING WINDS UPWARDS OF 60 KTS ABOUT 2KFT ABOVE THE SURFACE OVER CENTRAL WISCONSIN. WILL MENTION HIGHER GUSTS IN THE HWO. DESPITE MID-LEVEL HEIGHT FALLS...INSTABILITY APPEARS TOO MARGINAL FOR MUCH OF A THUNDER CHANCE. BUT WITH PWATS OVER AN INCH AND THE SLOWLY FORWARD PROGRESSION...DECENT RAINS ARE LIKELY OVER CENTRAL AND EAST-CENTRAL WISCONSIN OF A HALF INCH TO AN INCH. NORTHERN AND NE WISCONSIN WILL BE RELATIVELY DRIER DUE TO THE DRY NE LOW LEVEL FLOW BUT THAT AREA SHOULD SEE RAIN TOO. HIGHS ONLY IN THE LOW TO MIDDLE 40S. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 238 PM CDT SUN APR 27 2014 PCPN TRENDS THROUGHOUT THE PERIOD...AND STRONG E-NE WINDS MONDAY NIGHT INTO TUESDAY MORNING...ARE THE MAIN FCST CONCERNS. AN UPPER LEVEL LOW WILL MOVE TOWARD THE UPPER MISSISSIPPI VALLEY ON MONDAY NIGHT...REMAIN OVER THE WESTERN GREAT LAKES FROM TUESDAY THROUGH THURSDAY...THEN WEAKEN AND GRADUALLY SHIFT NE ON THURSDAY NIGHT AND FRIDAY. ALTHOUGH PCPN WILL BE IN THE FCST THROUGHOUT THE PERIOD...THE BEST RAINFALL SHOULD OCCUR AS A STRONG S/W TROF ROTATES THROUGH LATE MONDAY NIGHT INTO TUESDAY MORNING...AND AS ANOTHER WAVE OR WEAK UPPER LOW AFFECTS NE/N WI LATE TUESDAY NIGHT INTO WEDNESDAY. PCPN SHOULD BECOME MORE SCATTERED IN NATURE DURING THE LATTER HALF OF THE WEEK. MOST OF THE PCPN SHOULD FALL AS RAIN... ALTHOUGH A MIX OF RAIN/SNOW IS POSSIBLE OVER PARTS OF NC/FAR NE WI LATE MON NGT/EARLY TUE...AND AGAIN LATE WED NGT/EARLY THU AND LATE THU NGT/EARLY FRI. SIGNIFICANT RAINFALL AMOUNTS MAY CAUSE SOME MINOR RIVER FLOODING DURING THE UPCOMING WORK WEEK. A STRONG PRESSURE GRADIENT WILL SET UP BETWEEN A LARGE HUDSON BAY HIGH AND LOW PRESSURE APPROACHING FROM THE CENTRAL PLAINS ON MON NGT. WITH ENE WINDS OF 35-50 KTS ABOUT A THOUSAND FEET OFF THE SFC...STRONG GUSTS OF 30 TO 40 MPH MAY OCCUR IN THE FAVORED LOCATIONS...MAINLY CENTRAL WI AND THE FOX VALLEY. THE WINDS ARE EXPECTED TO DECREASE AS AN INVERTED SFC TROF ARRIVES AND THE GRADIENT WEAKENS TUESDAY AFTERNOON. THE MAIN WEATHER FEATURE FOR NEXT WEEKEND IS A COLD FRONT THAT IS PROGGED TO MOVE THROUGH THE REGION ON SUNDAY. THIS LOOKS LIKE A FAIRLY DYNAMIC SYSTEM...SO POPS MAY NEED TO BE INCREASED WITH SUBSEQUENT FCSTS. TEMPERATURES WILL REMAIN WELL BELOW NORMAL...WITH HIGHS IN THE 40S AND LOWER 50S THROUGH MOST OF THE PERIOD. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 557 PM CDT SUN APR 27 2014 BANDS OF RAIN WITH EMBEDDED STORMS WILL LIFT NORTHWARD OF THE STATE AS SOUTH WINDS ALOFT BRING IN INCREASING MOISTURE. MEANWHILE DRY AIR ON EASTERLY WINDS WILL CONTINUE TO POUR INTO THE AREA TO KEEP CIGS MAINLY AT VFR LEVELS FOR MOST OF TONIGHT. AS SHOWERS BECOME MORE WIDESPREAD FROM SOUTHWEST TO NORTHEAST LATER TONIGHT INTO MONDAY...CIGS WILL ALSO LOWER TO MVFR LEVELS FROM SOUTHWEST TO NORTHEAST LATE TONIGHT INTO MONDAY. COMPACT PRESSURE GRADIENT AHEAD OF A LARGE SURFACE LOW OVER THE CENTRAL PLAINS WILL ENSURE GUSTY WINDS AT THE SURFACE FOR A FEW DAYS ALONG WITH LLWS CONDITIONS DUE TO 2000 FOOT WINDS WINDS UP TO 50 KTS THROUGH MONDAY. && .HYDROLOGY... ISSUED AT 238 PM CDT SUN APR 27 2014 RAINFALL TOTALS OF 1.5 INCHES OVER FAR NORTHERN WI...AND 1.5 TO 2.5 INCHES OVER THE SRN THREE-QUARTERS OF THE FCST AREA...ARE EXPECTED DURING THE SUNDAY NGT THROUGH WEDNESDAY NGT PERIOD. THE RESULTING RUNOFF COULD CAUSE SOME MINOR RIVER FLOODING...AS SEVERAL RIVERS STILL REMAIN ABOVE BANKFULL. WILL CONTINUE TO MENTION THE RIVER FLOODING THREAT IN A HYDROLOGIC OUTLOOK AND THE HAZARDOUS WEATHER OUTLOOK. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......TDH HYDROLOGY......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
336 PM CDT SUN APR 27 2014 .SHORT TERM... TONIGHT AND MONDAY...FORECAST CONFIDENCE IS HIGH. SCATTERED SHOWERS CONTINUE TO DEVELOP ACROSS WESTERN PORTIONS OF THE AREA...WITH MORE SHOWERS AND STORMS DEVELOPING INTO WEST CENTRAL TO NORTH CENTRAL ILLINOIS. THESE CONTINUE TO DEVELOP ON THE 850 MB LOW LEVEL JET AND FOCUSED LOW LEVEL WARM AIR ADVECTION. ADDED POPS THROUGH THE REST OF THE AFTERNOON TO ACCOUNT FOR THE CURRENT SHOWERS OVER THE WESTERN COUNTIES. THE ACTIVITY TO OUR SOUTH MAY MOVE INTO THE SOUTHERN PORTIONS OF THE AREA BY 00Z MONDAY PER HRRR AND 4KM WRF/NMM MODELS. ELEVATED CAPES ARE A FEW HUNDRED J/KG...SO COULD HEAR CLAPS OF THUNDER AS WELL. THUS...KEPT THE POPS GOING INTO THE EARLY EVENING IN THE WEST AND SOUTHWEST COUNTIES. MAY HAVE TO GO HIGHER WITH POPS IF THIS ACTIVITY REMAINS ORGANIZED. HRRR AND 4KM WRF/NMM MODELS BRINGING MAIN WARM CONVEYOR BELT RAIN INTO THE AREA AT SLIGHTLY DIFFERENT TIMES...THE HRRR NOT UNTIL AFTER MIDNIGHT AND THE WRF/NMM AFTER 03Z MONDAY. USED THE 4KM WRF/NMM FOR TIMING...AS IT SEEMS TO HAVE A DECENT HANDLE ON CURRENT CONVECTION AND PRECIPITATION. HIGH POPS THEN LINGER LATER TONIGHT INTO MONDAY...WITH WARM CONVEYOR BELT RAIN OVER THE AREA. ISOLATED THUNDER KEPT WITH WEAK ELEVATED CAPE. COULD SEE LIGHTER RAIN IN THE AFTERNOON IN THE WESTERN COUNTIES...AS BEST UPWARD VERTICAL MOTION SHIFTS NORTH OF THAT AREA FOR A TIME. QPF TONIGHT INTO MONDAY NIGHT IS FORECAST BETWEEN 1.75 AND AROUND 2.00 INCHES. GUSTY EAST WINDS WILL LINGER TONIGHT AND MONDAY...WITH TIGHT PRESSURE GRADIENT ACROSS THE AREA. GUSTS TO 30 TO 33 KNOTS ARE EXPECTED AT TIMES. MAY SEE A FEW GUSTS AND SUSTAINED WINDS GET NEAR WIND ADVISORY LEVELS...MAINLY IN THE WEST...WITH STRONG LOW LEVEL WINDS JUST OFF THE SURFACE. MOST GUSTS WILL REMAIN BELOW CRITERIA. TEMPERATURES WILL REMAIN COOL WITH THE RAIN AND GUSTY EAST WINDS. MONDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM. THE OCCLUDED LOW WILL BE OVER FAR ERN NE EARLY MONDAY EVENING AND SLOWLY MOVE EWD. THE UPPER TROUGH AXIS EXTENDING FROM THE OCCLUSION WILL PIVOT NWD THROUGH WI MON NT...BRINGING ANOTHER ROUND OF WIDESPREAD MODERATE RAINFALL. THE OCCLUDED FRONT WILL MAKE IT TO THE IL/WI BORDER BY 12Z TUE. THE SFC LOW WILL THEN BECOME A BROAD N-S TROUGH OF LOW PRESSURE FROM SRN WI THROUGH IL. THIS WILL BRING THE OCCLUDED FRONT NWD INTO CENTRAL WI...THUS MILDER TEMPS ARE EXPECTED FOR TUE BUT SHOWERY CONDITIONS WILL CONTINUE ALONG WITH CHANCES OF TSTORMS WITH THE WARMER AND MORE UNSTABLE CONDITIONS. THE LARGE UPPER LOW OVER THE UPPER MS RIVER VALLEY WILL THEN AID IN ANOTHER ROUND OF CYCLOGENESIS OVER MI TUE NT BUT THAT WILL ALSO QUICKLY OCCLUDE WITH THE LOW OVER WI OR MI FOR WED. THE LARGE UPPER LOW ALOFT WILL ENSURE SHOWERY CONDITIONS CONTINUING THROUGH THIS PERIOD. AROUND 2 INCHES OF RAIN IS FORECAST FROM TNT THROUGH MON NT WITH SHOWERY CONDITIONS EXPECTED AFTERWARD. REISSUED THE HYDROLOGIC OUTLOOK WITH MANY RIVERS EXPECTED TO BE AT ABOVE NORMAL FLOWS WITH A FEW REACHING MINOR FLOOD STAGE. .LONG TERM... THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM THE LARGE OCCLUDED LOW WILL TAKE UNTIL ABOUT SAT TO MOVE AWAY WITH A WEAK RIDGE OF HIGH PRESSURE SHIFTING EWD ACROSS THE REGION. ANOTHER STRONG SHORTWAVE TROUGH AND SFC WAVE WITH THE POLAR JET STREAM WILL THEN QUICKLY MOVE EWD ACROSS WI FOR SUN. THUS THE RAIN CHANCES WILL CONTINUE THROUGH THE EXTENDED AS WELL. BELOW NORMAL TEMPS TO PREVAIL. && .AVIATION/00Z TAFS/... SCATTERED SHOWERS AND AN ISOLATED STORM ARE POSSIBLE THROUGH EARLY THIS EVENING...ESPECIALLY AT MADISON. COULD SEE MVFR VISIBILITIES IF ANY OF THESE GO OVER THE AIRPORT. FOR NOW...MAY PUT VICINITY SHOWERS IN TAF AT MADISON. MAIN ROUND OF MODERATE RAIN/SHOWERS WILL MOVE NORTHEAST INTO TAF SITES THIS EVENING...BY 03Z MONDAY AT MADISON AND 06Z MONDAY AT THE EASTERN SITES. THE RAIN WILL THEN LINGER LATER TONIGHT AND MONDAY. MVFR CEILINGS AND VISIBILITIES ARE EXPECTED DURING THIS TIME...WITH IFR VISIBILITIES POSSIBLE IN HEAVIER RAIN. ISOLATED THUNDERSTORMS ARE POSSIBLE...BUT WILL LEAVE MENTION OUT OF TAFS FOR NOW. GUSTY EAST WINDS WILL LINGER TONIGHT AND MONDAY...AS LOW PRESSURE SLOWLY MOVES TOWARD THE REGION FROM THE WEST. SOME GUSTS TO 30 KNOTS ARE EXPECTED. SOME POTENTIAL FOR LOW LEVEL WIND SHEAR TONIGHT INTO EARLY MONDAY MORNING...AS EASTERLY 1500 FOOT WINDS APPROACHING 50 TO 55 KNOTS. STILL FEEL THAT SUSTAINED WINDS AND GUSTS WILL BE STRONG ENOUGH TO PREVENT MENTION IN TAFS FOR NOW. && .MARINE... SMALL CRAFT ADVISORY CONTINUES FOR THE NEARSHORE WATERS OF LAKE MICHIGAN UNTIL LATER TUESDAY AFTERNOON. WINDS ARE EXPECTED TO RAMP BACK UPWARDS BY EARLY EVENING...WITH TIGHT PRESSURE GRADIENT WITH APPROACHING LOW PRESSURE FROM THE WEST. GUSTY EAST WINDS ARE THEN EXPECTED TO LINGER INTO MONDAY. GUSTS TO 30 KNOTS ARE EXPECTED TONIGHT INTO MONDAY...WITH A FEW TO 35 KNOTS. NOT EXPECTING GALE FORCE GUSTS TO BE FREQUENT ENOUGH FOR A GALE WARNING AT THIS TIME. WINDS WILL THEN SLOWLY WEAKEN MONDAY NIGHT AND TUESDAY. HIGH WAVES ARE EXPECTED WITH THE GUSTY ONSHORE WINDS TONIGHT INTO TUESDAY AFTERNOON. THEY SHOULD BUILD TO 6 TO 10 FEET TONIGHT INTO MONDAY...WITH SOME 8 TO 12 FOOT WAVES POSSIBLE SOUTH OF NORTH POINT LIGHTHOUSE. WAVES WILL SLOWLY SUBSIDE MONDAY NIGHT INTO TUESDAY...FALLING BELOW 4 FEET BY LATE TUESDAY AFTERNOON. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 4 PM CDT TUESDAY FOR LMZ643>646. && $$ TONIGHT/MONDAY AND AVIATION/MARINE...WOOD MONDAY NIGHT THROUGH SUNDAY...GEHRING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
313 PM CDT SUN APR 27 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 313 PM CDT SUN APR 27 2014 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHING ALONG THE BRITISH COLUMBIA COAST...A POTENT NEGATIVELY TILTED TROUGH AND UPPER LOW OVER KANSAS...AND A STRONG UPPER LEVEL RIDGE FROM THE SOUTHEASTERN U.S. INTO MANITOBA. IN- BETWEEN THE UPPER LOW AND RIDGE...PROFILER AND VWP DATA SHOWED A 30- 50 KT JET CORE AT 850MB FROM THE WESTERN GULF OF MEXICO NORTHWARD THROUGH MINNESOTA RAPIDLY TRANSPORTING MOISTURE NORTHWARD. GOES PRECIPITABLE WATER IMAGERY DEPICTED VALUES OF 1-1.5 INCHES ENCOMPASSING MUCH OF IOWA SOUTHWARD INTO LOUISIANA...WITH LOWER VALUES OF LESS THAN 0.5 INCH OVER MUCH OF KANSAS INTO WESTERN OKLAHOMA WHERE A DRY SLOT EXISTS. ALONG AND JUST EAST/NORTHEAST OF THIS GRADIENT OF PRECIPITABLE WATER...NUMEROUS SHOWERS AND THUNDERSTORMS HAVE DEVELOPED FROM CENTRAL IOWA AND MISSOURI. SOME OF THESE STORMS ARE INTENSE TOO...MOSTLY SOUTH OF I-80 WHERE 750-1500 J/KG OF MLCAPE EXISTS PER RAP ANALYSIS. FARTHER NORTHEAST... SHOWERS AND EMBEDDED THUNDERSTORMS THAT AFFECTED THE FORECAST AREA THIS MORNING HAVE MOSTLY LIFTED NORTH OF I-90. THESE ARE ASSOCIATED WITH MID-LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION OF AN UPPER JET OVER LAKE SUPERIOR. LASTLY...A TIGHT PRESSURE GRADIENT IN PLACE COMBINED WITH THAT AFOREMENTIONED STRONG 850MB JET CORE HAS LED TO BRISK EAST WINDS. THESE HAVE BEEN SUSTAINED AT 15-35 MPH WITH GUSTS OF 25-45 MPH...STRONGEST WEST OF THE MS RIVER. VERY GOOD MODEL AGREEMENT CONTINUES THAT THE BAND OF SHOWERS AND THUNDERSTORMS TO OUR SOUTHWEST WILL LIFT NORTHEAST THROUGH THE FORECAST AREA TONIGHT INTO MONDAY MORNING. THIS IS ALL IN RESPONSE TOO THE UPPER LOW AND ASSOCIATED SHORTWAVE TROUGH LIFTING INTO NEBRASKA AND IOWA BY 18Z MONDAY. THE QUESTION IS AMOUNT WHICH HAS BIG IMPACTS ON POTENTIAL FOR RIVER FLOODING. THE AMOUNT HAS STRONG TIES TO EVOLUTION OF CONVECTION OVER WESTERN MISSOURI AND SOUTHWEST IOWA IN WHICH THERE ARE THREE SCENARIOS... 1. THE CONVECTION TURNS INTO A FORWARD PROPAGATING SQUALL LINE...ESSENTIALLY LIMITING HEAVIER RAINFALL INTO THE FORECAST AREA. THIS SQUALL LINE FALLS APART OVER ILLINOIS LATE THIS EVENING AS IT RUNS INTO MORE STABLE AIR. 2. THE CONVECTION WEAKENS AS IT PUSHES EAST...RESULTING IN A PERSISTENT WARM CONVEYOR BELT OF SHOWERS AND EMBEDDED THUNDERSTORMS. THE TRAINING FACTOR COMES INTO PLAY...ALLOWING FOR HEAVIER RAINFALL...ESPECIALLY ACROSS NORTHEAST IOWA THIS EVENING. 3. THE CONVECTION WEAKENS AS IT PUSHES EAST...AND ESSENTIALLY MUCH OF THE SHOWER ACTIVITY FALLS APART BY 04Z. ALL THREE IDEAS ARE CERTAINLY PLAUSIBLE...BUT IT IS SERIOUSLY WORTH NOTING THE CONVECTION HAS BEEN OUTRUNNING MOST MODELS. THE ONLY MODEL THAT HAS BEEN HANDLING THIS WELL IS THE 00Z SPC WRF-NMM... WHICH IS SCENARIO NUMBER 3 ABOVE. THEREFORE...HAVE TRIED TO LEAN MORE TOWARDS THAT FOR PRECIPITATION CHANCES AND QPF. STILL...THE FORECAST MAY BE OVERDONE...ESPECIALLY WITH PRECIPITATION CHANCES IN THAT 04-09Z TIME FRAME. WOULD THINK THAT PERISTENT 850MB MOISTURE TRANSPORT WOULD AT LEAST CONTINUE SOME SHOWER ACTIVITY AND NOT COMPLETELY END...THUS THE HIGHER CHANCES IN THE FORECAST. ALL THREE SCENARIOS ABOVE REGENERATE SHOWERS AND EMBEDDED THUNDERSTORM ACTIVITY OVER THE FORECAST AREA AROUND 09Z...ASSOCIATED WITH DPVA FROM THE APPROACHING NEGATIVELY TILTED SHORTWAVE TROUGH. SEE HYDROLOGY SECTION BELOW FOR IMPACT ON RIVERS. AFTER THE RAIN AND CONVECTION TONIGHT/MONDAY MORNING...ATTENTION THEN TURNS TO A WARM FRONT PROGGED TO LIFT THROUGH IOWA. THE MAJORITY OF MODELS KEEP IT JUST SOUTH OF THE FORECAST AREA...EITHER ALONG OR SOUTH OF US-20. THE NORTHWARD PROGRESS OF THE FRONT HINGES QUITE A BIT ON MORNING PRECIPITATION. CONVECTION LOOKS LIKELY TO FIRE ALONG AND SOUTH OF THIS FRONTAL BOUNDARY. SOME OF THIS CONVECTION COULD CREEP INTO FAR SOUTHERN PORTIONS OF THE FORECAST AREA IN THE LATE AFTERNOON...AND POSSIBLY BE SEVERE. NOTE THAT A VERY TIGHT GRADIENT OF INSTABILITY WILL EXIST...SO ANY SEVERE THREAT SHOULD BE CONFINED TO FAYETTE EAST TO GRANT COUNTIES. LASTLY...REGARDING THE WIND ADVISORY...AS EXPECTED THE CONDITIONS HAVE BEEN MARGINAL. WILL KEEP IT GOING THROUGH 9 PM AS SUSTAINED SPEEDS CONTINUE TO PULSE UP AND DOWN TO 30 MPH. THERE IS A POSSIBILITY THE ADVISORY MAY NEED TO BE EXTENDED TO MIDNIGHT SEEING SOME LAV GUIDANCE HOLDING RST...TOB AND OLZ BETWEEN 25-30 KT TO 06Z. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 313 PM CDT SUN APR 27 2014 THE UPPER LOW OVER NEBRASKA ON MONDAY IS THE MAIN FEATURE OF FOCUS FOR THE LONG TERM PERIOD. MODELS CONTINUE TO SUGGEST THIS UPPER LOW WILL PLAGUE THE FORECAST AREA THROUGH AT LEAST THURSDAY AS IT SLOWLY TRACKS NORTHEAST INTO UPPER MICHIGAN. HEADING INTO THE WEEKEND...THE UPPER PATTERN REMAINS COOL AS RIDGING HOLDS IN PLACE OVER THE WESTERN U.S. INTO WESTERN CANADA...CAUSING TROUGHING TO PERSIST OVER THE GREAT LAKES REGION. THIS IS VERY WELL AGREED UPON BY THE 27.06Z/12Z GFS AND 27.00Z/12Z ECMWF. FOR MONDAY NIGHT INTO TUESDAY. CONDITIONS REMAIN FAVORABLE FOR A BAND OF SHOWERS TO FORM JUST NORTH OF THAT WARM FRONTAL BOUNDARY IN IOWA MONDAY EVENING...ASSOCIATED WITH DPVA FORCING AND 800-900MB FRONTOGENESIS. THIS BAND...AFFECTING LOCATIONS SOUTH OF I-90 MONDAY EVENING...SHOULD TRANSLATE NORTHWARD TO ALONG AND NORTH OF I-90 BY TUESDAY MORNING...WITH PRECIPITATION POSSIBLY TAILING OFF TO THE SOUTH. THEN WE GET INTO A COLD CONVEYOR BELT SCENARIO FOR TUESDAY AFTERNOON OVER NORTHWESTERN SECTIONS OF THE FORECAST AREA. OTHER SHOWERS SHOULD POP UP ELSEWHERE UNDER THE UPPER LOW DUE TO MID LEVEL COLD AIR. THERE COULD EVEN BE SOME THUNDER WITH THEM...BUT CONFIDENCE TOO LOW TO INCLUDE RIGHT NOW. FROM TUESDAY NIGHT THROUGH THURSDAY...THE FORECAST AREA PRETTY MUCH SITS IN A GRADUALLY WEAKENING COLD CONVEYOR BELT OF SHOWERS...WITH PERHAPS SOME DIURNAL ENHANCEMENT THAT COULD INCREASE COVERAGE. GIVEN HIGH CONFIDENCE OF PRECIPITATION AROUND...HAVE USED COVERAGE VERBIAGE. WITH PLENTY OF CLOUDS AND SHOWER ACTIVITY AROUND... COMBINED WITH 850MB TEMPS ONLY AROUND 0C PLUS OR MINUS 2 C...EXPECT CHILLY TEMPERATURES. CHANCES OF PRECIPITATION CONTINUE OFF AND ON FOR THURSDAY NIGHT RIGHT THROUGH SUNDAY AS SHORTWAVES DROP SOUTHEAST THROUGH THE GREAT LAKES TROUGHING. SOME SIGNAL THAT A SHORTWAVE TROUGH ON SUNDAY MIGHT BE MORE POTENT...SO CHANCES MAY NEED TO BE RAISED BEYOND THE CURRENT FORECAST OF A MODEL CONSENSUS. AS IT STANDS RIGHT NOW THE AIR IS NOT COLD ENOUGH FOR SNOW...BUT ITS NOT FAR OFF. 850MB STANDARDIZED ANOMALIES GENERALLY HOLD AROUND 1 STANDARD DEVIATION BELOW NORMAL...OR BETWEEN -4C AND 0C. NEEDLESS TO SAY...BELOW NORMAL TEMPERATURES CONTINUE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1246 PM CDT SUN APR 27 2014 AT 27.17Z...A BAND OF SHOWERS AND IOSLATED THUNDERSTORMS WAS LOCATED ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. THE MESO MODELS ARE IN DECENT AGREEMENT THAT THIS BAND WILL MOVE OUT THE TAF SITES AROUND 27.1830Z AND THEN CEILINGS WILL RISE INTO THE 4 TO 8K FOOT LAYER. ANOTHER BAND OF SHOWERS AND THUNDERSTORMS WILL MOVE BACK INTO THE TAF SITES AROUND 28.00Z. AS THIS OCCURS...CEILINGS WILL ONCE AGAIN BECOME IFR/MVFR. BEYOND THIS PERIOD IS VERY UNCERTAIN DUE TO DIFFERING SOLUTIONS ON HOW THIS BAND IS HANDLED BY THE MESO MODELS. DUE TO THIS...PLAYED IT ON THE CONSERVATIVE SIDE AND KEPT IFR/MVFR CEILINGS FOR NOW. WITH KLSE ONLY INTERMITTENTLY GUSTING...KEPT LOW LEVEL WIND SHEAR IN THE FORECAST THROUGHOUT THE PERIOD. && .HYDROLOGY... ISSUED AT 313 PM CDT SUN APR 27 2014 PRECIPITATION FORECASTS REMAIN VERY UNCERTAIN FOR TONIGHT AS SHOWERS AND EMBEDDED THUNDERSTORMS OVER CENTRAL IOWA ARE MOVING FASTER THAN MOST MODELS. IN FACT...THE ONE MODEL THAT IS HANDLING THE PRECIPITATION WELL SUGGESTS WE COULD HAVE A BREAK OF 6 HOURS OF NO PRECIPITATION TONIGHT AFTER THEY PASS. ADDITIONALLY...THE CONVECTION TO THE SOUTH MAY END UP INGESTING MORE OF THE MOISTURE...LIMITING HEAVIER RAINFALL OVER THE FORECAST AREA. THIS SCENARIO IS LOOKING MORE LIKELY FOR TONIGHT. BETTER CONFIDENCE FOR MUCH OF THE AREA TO SEE ANYWHERE FROM 1/4 TO 1 INCH OF RAIN ON MONDAY...WITH ANOTHER 1/2 TO 1 INCH FROM MONDAY NIGHT INTO TUESDAY. IN SUMMARY...BASED ON RFC FORECAST DATA...CONFIDENCE WAS ONLY HIGH ENOUGH TO PUT A FLOOD WATCH ON THE TURKEY RIVER. SHOULD AROUND 1 INCH MATERIALIZE OVER THE BASIN THIS EVENING...THE WATCH WILL NEED TO BE UPGRADED. ELSEWHERE...HAVE CONTINUED THE ESF. THERE ARE SOME SIGNALS THAT HEAVIER QPF COULD FALL OVER WISCONSIN. SHOULD THIS MATERIALIZE...MORE FLOOD WATCHES FOR AREA RIVERS MAY BE REQUIRED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ086-087-094-095. IA...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ008>010-018-019- 029. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE HYDROLOGY...AJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND MONDAY ISSUED AT 238 PM CDT SUN APR 27 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW OCCLUDED LOW PRESSURE SPINNING OVER WESTERN KANSAS. A WARM FRONT EXTENDS FROM THIS LOW EASTWARD INTO THE OHIO VALLEY. NORTH OF THIS WARM FRONT...MID-LEVEL THETAE ADVECTION AND FGEN IS CONTRIBUTING TO A BAND OF LIGHT RAIN PROGRESSING NORTHWARD ACROSS THE FORECAST AREA THIS AFTERNOON. SHOWERS ARE TRYING TO REDEVELOP SOUTH OF THIS RAIN BAND OVER SOUTHWEST WISCONSIN...BUT COVERAGE IS SIGNIFICANTLY LESS OVER EASTERN IOWA AND NORTHERN ILLINOIS. THEN A POTENT LINE OF STORMS IS PROGRESSING NORTHEAST ACROSS IOWA AND MISSOURI. RAIN CHANCES AND AMOUNTS ARE THE MAIN FORECAST CONCERN IN THE SHORT TERM. TONIGHT...THE OCCLUDED CYCLONE OVER THE CENTRAL PLAINS WILL MOVE VERY LITTLE TO THE NORTHEAST FROM CENTRAL KANSAS TO NORTHEAST NEBRASKA WHILE HUDSON BAY HIGH PRESSURE REMAINS IN PLACE. ANTICIPATING THAT ARCING BAND OF RAIN ASSOCIATED WITH MID-LEVEL MOISTURE ADVECTION AND FGEN WILL HAVE WEAKENED AT THE START OF THE EVENING AS IT MOVES INTO A DRIER AIRMASS...BUT COULD STILL BE SOME SHOWERS HANGING ON ACROSS NORTHERN WISCONSIN AND WILL LEAVE A CHANCE IN THE FORECAST. THEN ANTICIPATE THAT THERE WILL BE A BREAK OR REDUCED COVERAGE OF PRECIP FOR A PERIOD THIS EVENING BEFORE THE LINE OF CONVECTION OVER THE PLAINS PIVOTS AS IT MOVES NE INTO WISCONSIN. THINK THIS LINE WILL MAKE IT INTO CENTRAL WISCONSIN AND THE SOUTHERN FOX VALLEY LATE TONIGHT (THOUGH WILL NOT BE NEARLY AS INTENSE AS IT STANDS CURRENTLY) DUE TO INCREASING 900-800MB MOISTURE TRANSPORT AND FGEN. PRIOR TO THIS AREA OF RAIN ARRIVING...CANNOT RULE OUT SPOTTY TO SCATTERED SHOWERS REDEVELOPING. BUT IN GENERAL...WILL HAVE THE LOWEST CHANCE OF PRECIP EARLY IN THE EVENING AND THEN GRADUALLY INCREASE CHANCES THROUGH THE NIGHT. LOWS SHOULD BE RELATIVELY STEADY IN THE MIDDLE TO UPPER 30S. MONDAY...THE ARCING BAND OF RAIN WILL SLOWLY LIFT NORTHEAST THROUGH THE DAY BUT SHOULD BE GRADUALLY WEAKENING AS IT DOES SO. SOME CONCERN THAT THE RAINS COULD BRING DOWN SOME BEEFY GUSTS FROM ALOFT AS THE NAM IS DEPICTING WINDS UPWARDS OF 60 KTS ABOUT 2KFT ABOVE THE SURFACE OVER CENTRAL WISCONSIN. WILL MENTION HIGHER GUSTS IN THE HWO. DESPITE MID-LEVEL HEIGHT FALLS...INSTABILITY APPEARS TOO MARGINAL FOR MUCH OF A THUNDER CHANCE. BUT WITH PWATS OVER AN INCH AND THE SLOWLY FORWARD PROGRESSION...DECENT RAINS ARE LIKELY OVER CENTRAL AND EAST-CENTRAL WISCONSIN OF A HALF INCH TO AN INCH. NORTHERN AND NE WISCONSIN WILL BE RELATIVELY DRIER DUE TO THE DRY NE LOW LEVEL FLOW BUT THAT AREA SHOULD SEE RAIN TOO. HIGHS ONLY IN THE LOW TO MIDDLE 40S. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 238 PM CDT SUN APR 27 2014 PCPN TRENDS THROUGHOUT THE PERIOD...AND STRONG E-NE WINDS MONDAY NIGHT INTO TUESDAY MORNING...ARE THE MAIN FCST CONCERNS. AN UPPER LEVEL LOW WILL MOVE TOWARD THE UPPER MISSISSIPPI VALLEY ON MONDAY NIGHT...REMAIN OVER THE WESTERN GREAT LAKES FROM TUESDAY THROUGH THURSDAY...THEN WEAKEN AND GRADUALLY SHIFT NE ON THURSDAY NIGHT AND FRIDAY. ALTHOUGH PCPN WILL BE IN THE FCST THROUGHOUT THE PERIOD...THE BEST RAINFALL SHOULD OCCUR AS A STRONG S/W TROF ROTATES THROUGH LATE MONDAY NIGHT INTO TUESDAY MORNING...AND AS ANOTHER WAVE OR WEAK UPPER LOW AFFECTS NE/N WI LATE TUESDAY NIGHT INTO WEDNESDAY. PCPN SHOULD BECOME MORE SCATTERED IN NATURE DURING THE LATTER HALF OF THE WEEK. MOST OF THE PCPN SHOULD FALL AS RAIN... ALTHOUGH A MIX OF RAIN/SNOW IS POSSIBLE OVER PARTS OF NC/FAR NE WI LATE MON NGT/EARLY TUE...AND AGAIN LATE WED NGT/EARLY THU AND LATE THU NGT/EARLY FRI. SIGNIFICANT RAINFALL AMOUNTS MAY CAUSE SOME MINOR RIVER FLOODING DURING THE UPCOMING WORK WEEK. A STRONG PRESSURE GRADIENT WILL SET UP BETWEEN A LARGE HUDSON BAY HIGH AND LOW PRESSURE APPROACHING FROM THE CENTRAL PLAINS ON MON NGT. WITH ENE WINDS OF 35-50 KTS ABOUT A THOUSAND FEET OFF THE SFC...STRONG GUSTS OF 30 TO 40 MPH MAY OCCUR IN THE FAVORED LOCATIONS...MAINLY CENTRAL WI AND THE FOX VALLEY. THE WINDS ARE EXPECTED TO DECREASE AS AN INVERTED SFC TROF ARRIVES AND THE GRADIENT WEAKENS TUESDAY AFTERNOON. THE MAIN WEATHER FEATURE FOR NEXT WEEKEND IS A COLD FRONT THAT IS PROGGED TO MOVE THROUGH THE REGION ON SUNDAY. THIS LOOKS LIKE A FAIRLY DYNAMIC SYSTEM...SO POPS MAY NEED TO BE INCREASED WITH SUBSEQUENT FCSTS. TEMPERATURES WILL REMAIN WELL BELOW NORMAL...WITH HIGHS IN THE 40S AND LOWER 50S THROUGH MOST OF THE PERIOD. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1239 PM CDT SUN APR 27 2014 NORTH OF A WARM FRONT POSITIONED OVER THE CENTRAL MISSISSIPPI VALLEY...AREAS OF RAIN WILL BE LIFTING NORTH ACROSS THE REGION. THE FIRST WAVE OF RAIN WILL MOVE THROUGH EARLY THIS AFTERNOON BRINGING SCT MVFR CIGS AND VSBYS MAINLY TO CENTRAL AND NORTH-CENTRAL WISCONSIN. THE REST OF THE REGION SHOULD REMAIN VFR THANKS TO DRY LOW LEVEL AIR. A BREAK IN THE RAINFALL SHOULD OCCUR LATER THIS AFTERNOON INTO THIS EVENING BEFORE THE NEXT ROUND PUSHES NORTHWARD LATE TONIGHT INTO MONDAY MORNING. DESPITE THE BREAK IN THE RAIN...EAST WINDS WILL REMAIN GUSTY AND WIND SHEAR UP TO 55 KTS WILL REMAIN PRESENT ALOFT. LITTLE CHANGES IN REGARDS TO THE GUSTY EAST WINDS AND WIND SHEAR THROUGH MONDAY. && .HYDROLOGY... ISSUED AT 238 PM CDT SUN APR 27 2014 RAINFALL TOTALS OF 1.5 INCHES OVER FAR NORTHERN WI...AND 1.5 TO 2.5 INCHES OVER THE SRN THREE-QUARTERS OF THE FCST AREA...ARE EXPECTED DURING THE SUNDAY NGT THROUGH WEDNESDAY NGT PERIOD. THE RESULTING RUNOFF COULD CAUSE SOME MINOR RIVER FLOODING...AS SEVERAL RIVERS STILL REMAIN ABOVE BANKFULL. WILL CONTINUE TO MENTION THE RIVER FLOODING THREAT IN A HYDROLOGIC OUTLOOK AND THE HAZARDOUS WEATHER OUTLOOK. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......MPC HYDROLOGY......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1249 PM CDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 PM CDT SUN APR 27 2014 BEGINNING TO FEEL THE AFFECTS OF DEEP LOW PRESSURE CENTERED IN NEW MEXICO WITH BANDS OF ELEVATED THUNDERSTORMS ACROSS THE REGION FROM KABR TO KDVN AND HEADING FOR THE FORECAST AREA. TRIED TO MAKE SOME TIMING IMPROVEMENTS TO THE PRECIPITATION TODAY...AND THEN SOME LARGER CHANGES TO OVERNIGHT RAINFALL TOTALS /UP IN THE WEST BY .3 TO .5 INCHES/...BUT MUCH OF TONIGHTS FORECAST LEFT AS WAS. GOES WATER VAPOR IMAGERY SHOWING A DEEP LOW WITH TROPOPAUSE FOLD DOWN TO 700 MB OVER NEW MEXICO PER RAP TROP ANALYSIS. SURFACE PRESSURE CONTINUES TO FALL ACROSS SD/MN /1 MB PER HOUR/ INCREASING THE PRESSURE GRADIENT...AND WINDS ARE RESPONDING WITH 25 MPH GUSTS TO 35 MPH ALREADY TONIGHT IN EASTERLY FLOW. SURFACE LOW PRESSURE NOW CENTERED IN NERN CO TO WRN NE AT 986 MB. SURFACE WARM SECTOR CONTINUING TO MOISTEN WITH 60F DEWPOINT LINE NOW INTO NEB. NORTH OF THE W-E FRONT NEAR OMAHA-KSTL LINE...DEWPOINTS CONTINUE TO FALL IN STRONG DRIER EASTERLY FLOW /30S/...PRODUCING SOME FIGHT TO RAIN SHOWERS TO HIT THE SURFACE /NOT THE TSRA THOUGH AS HOURLY 0.25 INCH REPORTS ARE COMMON IN IA/. GOES BLENDED PRECIPITABLE WATER /PW/ HOURLY LOOP SHOWS THE MAIN PLUME OF MOISTURE FOR INFLOW INTO TONIGHTS RAIN IS SHIFTING NORTH THRU OK/AR AT THIS TIME...WITH 1.5 INCH VALUES. ALREADY PRESENT FROM THE DAKOTAS SEWRD INTO IA...A PW AXIS EXISTS OF ABOUT 0.60 INCHES WHICH IS 125-150 PERCENT NORMAL. THIS IS MAINLY MOISTURE ABOVE 700MB /PER 00Z RAOB AT KABR/ AND ALSO CO-LOCATED WITH PRETTY STEEP 500-700MB LAPSE RATES OF 7-8C/KM...WHICH IS WHERE THE RADAR ECHOES HAVE DEVELOPED TONIGHT WITH MOST LIGHTNING. LAPSE RATE GRADIENT RUNS KABR-KMCW WITH MAX OVER NEB AT 06Z. THE LATEST RAP ANALYSIS SHOWS THESE LAPSE RATE STEEPENING AS AN ELEVATED MIXED LAYER MOVES IN FROM THE SOUTH...WHICH PUSHES THE GRADIENT AND DESTABILIZATION INTO THE WESTERN FORECAST AREA BY SUNRISE. LAPSE RATES AND INSTABILITY ARE STILL FORECAST TO REMAIN MAINLY WEST OF THE FORECAST AREA THROUGH TONIGHT. SOME 200 J/KG OF INSTABILITY EXISTS ACROSS THE VERY WESTERN FORECAST AREA SO WE SHOULD SEE A DECREASE IN THE LIGHTNING AS THESE STORMS MOVE NORTH. THESE STORMS ARE LOCATED ON THE NOSE OF THE 750-850MB MOISTURE TRANSPORT AND LLJ CONVERGENCE. KDMX IS 60 KTS FROM THE SOUTH PER RADAR AND KARX 88D SHOWED 40 KTS FROM THE SE...SO NICE CONVERGENCE TO MOIST PLUME ALOFT. LATEST RAP AND LONGER RANGE MODELS AGREE ON MOVING THIS SHOWER AND SCT TSRA REGION NORTHWARD THROUGH THE AREA THIS MORNING WITH TRANSPORT CONVERGENCE. TSRA SHOULD GIVE WAY TO MORE SHRA. THE HRRR AND RAP...AS WELL AS NAM AND GFS...HAVE THE IDEA OF A DECREASE OR LULL IN SHOWERY ACTIVITY THIS AFTERNOON AS TRANSPORT AND MOISTURE ADVECTION SHIFTS NORTHEAST. HAVE BUILT THIS INTO THE RAIN CHANCES...WITH AN INCREASE LATE TODAY AND EVENING AS MAIN MOIST PLUME AND FORCING RETURNS WITH AROUND 1 INCH OF RAIN MOST AREAS. HAVE ONLY BOTTOMED THE RAIN CHANCES OUT TO ABOUT 50 PERCENT THIS AFTERNOON...BUT IT IS A START. WIND ADVISORY IS ON TRACK FOR TODAY ALTHOUGH THE GFS IS MUCH LESS ROBUST WITH WINDS TODAY. FROM CURRENT OBSERVATIONS GUSTING TO 35 MPH WEST OF MISS RIVER AND WITH AN INCREASE IN THE PRESSURE GRADIENT TODAY...WIND ADVISORY LOOKS ON TRACK. KARX 88D HAS 45-50 KTS AT 500M ABOVE THE RADAR AT 08Z. IT COULD BE RATHER GUSTY EAST OF THE RIVER TOO IN WI WITH STRONG WINDS RIGHT ABOVE THE SURFACE AND SOME SHALLOW MIXING THIS AFTERNOON WITHOUT RAIN. GUSTS IN THE 30S ARE IN THE FORECAST...BUT WE MAY NEED TO EXPAND THE ADVISORY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 339 AM CDT SUN APR 27 2014 RAIN BAND CONTINUES TO AFFECT WI AREAS MONDAY MORNING AND A BREAK SEEMS TO OCCUR THEN BEFORE THE WARM FRONT AGAIN BECOMES ACTIVE IN THE AFTERNOON ACROSS THE SOUTH. THIS WILL BE IN RESPONSE TO ANOTHER STRONG SPOKE OF SHORTWAVE ENERGY ROTATING NORTH AROUND THE LONGWAVE TROUGH. SEVERE WEATHER CHANCES REALLY BANK ON INSTABILITY OVER THE AREA /DUH/ AND THE WARM SECTOR/FRONT LOCATION WHICH HAS BEEN FORECAST RIGHT ON THE SOUTHERN FORECAST AREA BORDER OR SOUTH...AND RUNNING W-E. THE SHORTWAVE TROUGH ROTATING NORTHWARD LOOKS TO DEVELOP LIFT AND CLOUDS/RAIN BY MID-DAY MONDAY WHICH DOESNT NOT LEAVE MUCH TIME TO DESTABILIZE. THE LATEST SPC FORECAST HAS SHIFTED THE DAY 2 SLIGHT RISK NORTH TO JUST SOUTH OF KDBQ. THERE SEEMS TO BE SOME ELEVATED INSTABILITY NORTH OF THE FRONT IN THE SOUTHERN FORECAST AREA FOR SOME STRONG LOW-TOPPED STORMS. WIND SHEAR IS FAIR SO DYNAMIC LIFT WILL HAVE TO ASSIST TO INVIGORATE THE STORMS...BUT OVERALL THE THREAT SEEMS LOW BUT POSSIBLE...WITH MARGINAL WIND/HAIL. IF THE FRONT SHOULD MOVE INTO THE AREA...SOME LOW-LEVEL VORTICITY WOULD BE AVAILABLE...WHICH WOULD MAKE AN ISOLATED TORNADO POSSIBLE. AT THIS TIME...THE FRONT SEEMS CLOSE BUT NOT INTO THE AREA. WILL CONTINUE TO MENTION THE LIMITED THREAT ACROSS OUR SOUTHERN AREA MONDAY AFTERNOON/EVENING. MORE RAIN AGAIN AS THIS SHORTWAVE TROUGH MOVES NORTH AND ANOTHER THEN FOLLOW BEHIND FOR TUESDAY. THE LOW BEGINS TO SHIFT EAST ENHANCING THE DEFORMATION ON THE NORTH SIDE...SO ANOTHER INCH IS POSSIBLE AGAIN MONDAY NIGHT AND TUESDAY. OVERALL...SREF RUNS ARE CONSISTENT IN SHOWING 2-2.5 INCHES STORM TOTAL ACROSS THE AREA /MEAN/ WITH LITTLE SPREAD IN THE MEMBERS SURPRISINGLY. THIS IS OUR CURRENT FORECAST RAINFALL. SEE HYDROLOGY SECTION FOR IMPACTS ON RIVERS. WEDNESDAY THROUGH SATURDAY...A COOL AND SHOWERY WEEK UNDER THE INFLUENCE OF THE DEEP OCCLUDED LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1246 PM CDT SUN APR 27 2014 AT 27.17Z...A BAND OF SHOWERS AND IOSLATED THUNDERSTORMS WAS LOCATED ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. THE MESO MODELS ARE IN DECENT AGREEMENT THAT THIS BAND WILL MOVE OUT THE TAF SITES AROUND 27.1830Z AND THEN CEILINGS WILL RISE INTO THE 4 TO 8K FOOT LAYER. ANOTHER BAND OF SHOWERS AND THUNDERSTORMS WILL MOVE BACK INTO THE TAF SITES AROUND 28.00Z. AS THIS OCCURS...CEILINGS WILL ONCE AGAIN BECOME IFR/MVFR. BEYOND THIS PERIOD IS VERY UNCERTAIN DUE TO DIFFERING SOLUTIONS ON HOW THIS BAND IS HANDLED BY THE MESO MODELS. DUE TO THIS...PLAYED IT ON THE CONSERVATIVE SIDE AND KEPT IFR/MVFR CEILINGS FOR NOW. WITH KLSE ONLY INTERMITTENTLY GUSTING...KEPT LOW LEVEL WIND SHEAR IN THE FORECAST THROUGHOUT THE PERIOD. && .HYDROLOGY... ISSUED AT 339 AM CDT SUN APR 27 2014 WITH VALUES STILL IN THE 2-3 INCH RANGE FOR STORM TOTAL PRECIPITATION THROUGH TUESDAY...FLOODING ON AREA RIVERS IS STILL QUITE POSSIBLE. REVIEWING THE FORECASTS FOR THE CURRENT 72-HOUR RAINFALL AND ITS AFFECT ON RIVERS...THE RIVERS RESPOND BY RISING TO/NEAR MINOR FLOOD STAGE AT MANY SITES. THE DAY SHIFT TODAY WILL REVIEW THE INFORMATION AND ARE CONSIDERING...IN COOPERATION WITH THE RIVER FORECAST CENTER...PLACING THE 72 HOUR RAIN INTO THE ACTUAL FORECASTS. RECALL THE POSTED FORECASTS THAT ARE ISSUED ONLY USE 24 HOUR FORECAST RAINFALL. IN HIGHER CONFIDENCE SITUATIONS LIKE THIS EVENT...IT WOULD BE BETTER TO HAVE THAT 72 HOUR TOTAL INCLUDED. HOWEVER...USERS OF RIVER DATA CAN GO TO THE LINK BELOW TO SEE 72 HOUR RAINFALL RIVER HYDROGRAPHS AT ANY TIME /ALL LOWER CASE AND SCROLL TO BOTTOM OF PAGE/... WWW.CRH.NOAA.GOV/CRH/RFC/MAPGRAPHICALDISPLAY.PHP WILL HOLD OFF FROM ISSUING A FLOOD WATCH AS THE DAY SHIFT WILL HAVE TO VISIT THIS TOPIC WITH THE 72 HOUR RAINFALL RIVER && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ086-087-094-095. IA...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ008>010-018-019- 029. && $$ SHORT TERM...BAUMGARDT LONG TERM...BAUMGARDT AVIATION...BOYNE HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1214 PM CDT SUN APR 27 2014 .UPDATE...AREAS OF SHOWERS/RAIN MOVING NORTHEAST THROUGH THE NORTHWESTERN AND NORTHEASTERN PORTIONS OF THE AREA. THESE WERE BEING DRIVEN BY LOW LEVEL WARM AIR ADVECTION AND 850 MB LOW LEVEL JET. HRRR MODEL TAKING THIS PRECIPITATION NORTHEASTWARD AND OUT OF THE AREA BY 18Z TO 19Z SUNDAY...WHICH SEEMS REASONABLE. A FEW SHOWERS STILL MAY OCCUR THIS AFTERNOON...THOUGH MOST OF THE AREA SHOULD REMAIN DRY. MAIN ROUND OF MODERATE RAIN WITH WARM CONVEYOR BELT IS NOT EXPECTED UNTIL THIS EVENING. SO...ADJUSTED POPS DOWNWARD AFTER 18Z TO 19Z THIS AFTERNOON ACROSS THE AREA. GUSTY EAST WINDS WILL LINGER WITH TIGHT PRESSURE GRADIENT. SKIES SHOULD REMAIN MOSTLY CLOUDY...WITH A FEW BREAKS POSSIBLE. HIGHS SHOULD REMAIN IN THE MID 40S LAKESIDE...TO THE UPPER 40S INLAND NORTH...AND LOWER TO MID 50S INLAND SOUTH. && .AVIATION/18Z TAFS/...SHOWERS MAY AFFECT MADISON FOR THE NEXT HOUR BEFORE MOVING OFF TO THE NORTHEAST OR DIMINISHING. MAY SEE A SHOWER THIS AFTERNOON OCCUR...BUT MOST OF THE AREA SHOULD REMAIN DRY WITH VFR CONDITIONS. GUSTY EAST WINDS WILL LINGER. MAIN ROUND OF MODERATE RAIN/SHOWERS WILL MOVE NORTHEAST INTO TAF SITES THIS EVENING...BY 02Z MONDAY AT MADISON AND 05Z MONDAY AT THE EASTERN SITES. THE RAIN WILL THEN LINGER LATER TONIGHT AND MONDAY. MVFR CEILINGS AND VISIBILITIES ARE EXPECTED DURING THIS TIME...WITH IFR VISIBILITIES POSSIBLE IN HEAVIER RAIN. GUSTY EAST WINDS WILL LINGER TONIGHT AND MONDAY...AS LOW PRESSURE SLOWLY MOVES TOWARD THE REGION FROM THE WEST. SOME GUSTS TO 30 KNOTS ARE EXPECTED. SOME POTENTIAL FOR LOW LEVEL WIND SHEAR TONIGHT INTO EARLY MONDAY MORNING...AS EASTERLY 1500 FOOT WINDS APPROACH 50 KNOTS. FEEL SUSTAINED WINDS AND GUSTS WILL BE STRONG ENOUGH TO PREVENT MENTION IN TAFS FOR NOW. && .MARINE...SMALL CRAFT ADVISORY CONTINUES FOR THE NEARSHORE WATERS OF LAKE MICHIGAN UNTIL LATER TUESDAY AFTERNOON. TIGHT PRESSURE GRADIENT WITH APPROACHING LOW PRESSURE FROM THE WEST WILL CONTINUE TO BRING GUSTY EAST WINDS THIS AFTERNOON INTO MONDAY. GUSTS TO 30 KNOTS ARE EXPECTED TONIGHT INTO MONDAY...WITH A FEW TO 35 KNOTS. NOT EXPECTING GALE FORCE GUSTS TO BE FREQUENT ENOUGH FOR A GALE WARNING AT THIS TIME. WINDS WILL THEN SLOWLY WEAKEN MONDAY NIGHT AND TUESDAY. HIGH WAVES ARE EXPECTED WITH THE GUSTY ONSHORE WINDS THIS AFTERNOON INTO TUESDAY AFTERNOON. THEY SHOULD BUILD TO 6 TO 10 FEET TONIGHT INTO MONDAY...WITH SOME 8 TO 12 FOOT WAVES POSSIBLE SOUTH OF NORTH POINT LIGHTHOUSE. WAVES WILL SLOWLY SUBSIDE MONDAY NIGHT INTO TUESDAY...FALLING BELOW 4 FEET BY LATE TUESDAY AFTERNOON. && .PREV DISCUSSION... /ISSUED 530 AM CDT SUN APR 27 2014/ SHORT TERM...TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. HRRR HANDLING LIGHT RAIN WITH FIRST PUSH OF MAINLY 700MB WARM AIR ADVECTION...AIDED BY ULD IN RIGHT ENTRANCE REGION OF 250 MB JET MAX WELL. GETTING ISOLATED 0.01 AMOUNTS ON SOME OF THE OBSERVATIONS... WITH MAINLY TRACE AMOUNTS IN 10SM LIGHT RAIN FALLING FROM 9K TO 10K FT BASES WITH MOST OF THE REPORTS FROM NRN HALF OF THE CWA. BAND WILL SHIFT OUT OF FORECAST AREA BETWEEN 09Z AND 10Z WITH BETTER 700- 850 MB FRONTOGENETIC RESPONSE. NEXT BAND OF SHOWERS MORE CLOSELY TIED WITH 850 MB WAA AND NEXT ROUND OF 700-850 MB FRONTOGENESIS WILL ENTER THE SW CORNER OF THE CWA BY 12Z AND LIFT NORTH-NORTHEAST THROUGH CWA...EXITING TO THE NORTH. SOME CONVECTION IN IOWA ON NOSE OF STRONGEST 850 MB WINDS WHICH WILL BRUSH PAST TO THE WEST. WILL LIMIT ISOLATED THUNDER TO JUST THE FAR WEST/SOUTHWEST THIS MORNING. HAVE REDUCED POPS FOR A TIME FROM LATE MORNING INTO THE AFTERNOON TO REFLECT A POTENTIAL BREAK IN THE SHOWERS...ESPECIALLY IN THE EAST. COOL EASTERLY FLOW WILL HOLD TEMPS DOWN...WITH ONLY THE FAR SOUTH REACHING THE 50S AWAY FROM THE LAKE...AND THAT IS IF THERE IS THE EXPECTED BREAK IN THE PRECIPITATION. GULF OPENS UP TO THE SYSTEM BY THIS EVENING WITH PRECIPITABLE WATER VALUES AROUND 1 INCH WITHIN WARM CONVEYOR BELT. HAVE CATEGORICAL POPS SPREADING IN FROM WEST TO EAST WITH BETTER Q-VECTOR CONVERGENCE/SYSTEM DYNAMICS. BEGINNING OF A PROLONGED PERIOD OF WET WEATHER. QPF TOTALS BY MONDAY MORNING WILL RANGE FROM BETWEEN 1/3 OF AN INCH TO 1/2 INCH IN THE EAST...TO BETWEEN 3/4 INCH AND 1.3 INCHES IN THE FAR SOUTHWEST...WHERE WPC HAS A SLIGHT CHANCE/5 TO 10 PCT/OF EXCESSIVE RAINFALL. RIVERS WILL BE QUICK TO RESPOND TO THIS RAIN AS THEY ARE ALREADY HIGH FROM SNOW MELT AND PREVIOUS HEAVY RAINFALL...WITH SURROUNDING LOW-LANDS ALREADY SATURATED AND UNABLE TO HOLD EXCESS WATER FROM ENTERING THE MAINSTEM CHANNELS. MONDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM. THE OCCLUDED LOW PRESSURE SYSTEM WILL GRADUALLY BROADEN AS IT MOVES FROM NEBRASKA TO THE MN/WI/IA BORDER. THE 925MB WARM FRONT WILL BE STATIONED ACROSS NORTHERN IL MONDAY MORNING...THEN CREEP NORTHWARD INTO CENTRAL WI THROUGH TUESDAY AFTERNOON. MEANWHILE...THE 850MB WARM FRONT WILL REMAIN STATIONARY OVER CENTRAL WI THROUGH TUESDAY MORNING...THEN LIFT NORTHWARD AS THE CLOSED LOW APPROACHES SOUTHWEST WI. THE DEEP MOISTURE WILL CONTINUE TO STREAM INTO SOUTHERN WI THROUGH TUESDAY. WAVES OF VORTICITY AND WARM AIR ADVECTION LEAD TO STRONG UPWARD MOTION OVER SOUTHERN WI. THE STRONG DYNAMICS AND STEEP MID LEVEL LAPSE RATES WILL ALLOW FOR ELEVATED THUNDERSTORMS. RAINFALL RATES OF 1 TO 2 INCHES PER HOUR ARE EXPECTED WITH THESE STORMS. TIMING OF THESE WAVES IS STILL A LITTLE UNCERTAIN...SO DID NOT TRY TO TIME THESE WAVES IN THE FORECAST WEATHER GRIDS QUITE YET BUT THE TREND IS SHOWN IN THE QPF GRIDS. MODELS ARE LATCHING ON TO RAIN TAPERING OFF SOMEWHAT ACROSS SOUTHERN WI FOR MONDAY AFTERNOON. THEN ANOTHER BAND OF MODERATE TO HEAVY RAIN SHOWERS IS EXPECTED TO LIFT INTO SOUTHERN WI MON EVENING AND EXIT AROUND MIDNIGHT. FOR TUESDAY...YET ANOTHER ROUND OF SHOWERS AND ISOLATED THUNDER IS EXPECTED AS THE SURFACE LOW GETS INTO SOUTHWEST WI. THESE COULD BECOME SURFACE BASED SINCE THE SURFACE WARM FRONT WILL LIKELY REACH FAR SOUTHERN WI. TEMPERATURES WILL BE WARMER ON TUESDAY...BUT THEY WILL ULTIMATELY DEPEND ON SKY COVER AND EXACT LOCATION OF THE WARM FRONT. PRECIPITABLE WATER VALUES WILL RISE TO AROUND AN INCH WITH THIS PLUME OF MOISTURE STREAMING INTO SOUTHERN WI. THIS IS BETWEEN THE 75TH PERCENTILE AND 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. A CONSENSUS OF MODELS AND WPC YIELDS 1.5-2.00 INCHES FROM MON THROUGH TUE. A HYDROLOGIC OUTLOOK IS IN EFFECT TO ADDRESS THE RISE IN RIVERS AND THE POTENTIAL FOR MINOR FLOODING ON SOME RIVERS. LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...FORECAST CONFIDENCE MEDIUM. THE OCCLUDED LOW WILL MEANDER NORTHEAST OVER THE UPPER GREAT LAKES THROUGH FRIDAY MORNING. DRY AIR WRAPPING INTO THE OCCLUDED SYSTEM BY TUESDAY NIGHT WILL CUT OFF THE DEEP MOISTURE. CLOUDS AND SCATTERED SHOWERS WILL CONTINUE TO BE POSSIBLE THROUGH FRIDAY DUE TO THE CYCLONIC FLOW AND LINGERING LOW LEVEL MOISTURE. WINDS WILL GENERALLY BE OUT OF THE EAST FOR THE WEEK WHICH MEANS COOLER NEAR THE LAKE WITH HIGHS IN THE UPPER 40S THERE AND LOWER 50S INLAND. MODELS ARE SHOWING A BROAD UPPER TROUGH HANGING OUT OVER THE GREAT LAKES REGION THROUGH NEXT WEEKEND WHICH WOULD ALLOW FOR PERSISTENT CLOUDS...COOL TEMPERATURES AND INTERMITTENT SHOWERS. THERE WILL BE PERIODS OF DRY WEATHER FROM FRI THROUGH THE WEEKEND...BUT IT IS IMPOSSIBLE TO TIME IT RIGHT NOW. AVIATION/12Z TAFS/... FIRST BAND OF WIDELY SCATTERED SHOWERS IS LIFTING AWAY TO THE NORTHEAST WITH A SECOND BAND MOVING INTO SW WI. A FEW ISOLATED SHOWERS WILL AFFECT TAF SITES AHEAD OF THE SECOND BAND. UPSTREAM OBS CONFIRM PREVAILING VFR CONDITIONS EXPECTED...EVEN WITH THE SCATTERED SHOWERS...THROUGH THE DAY AS LOW-LEVEL DRY AIR WILL PREVENT CIGS FROM DROPPING BELOW VFR LEVELS AND ONLY SPOTTY SHOWERS MAY BRIEFLY DROP VSBYS BELOW 6SM. WILL HANDLE THESE LOWER VSBY SHOWERS AS THEY FORM AND APPROACH TAF SITES. ANY THUNDER LOOKS TO REMAIN SW OF TAF SITES TODAY. SUSTAINED EAST WINDS OF 15 TO 20 KNOTS ARE EXPECTED WITH GUSTS OF 25 TO 30 KNOTS BY LATE MORNING THROUGH TONIGHT. MVFR/IFR CONDITIONS WILL COME TONIGHT WITH STEADY SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORMS WITH MOISTURE STREAMING NORTH AHEAD OF APPROACHING LOW PRESSURE. THIS WILL BE THE START OF A PROLONGED PERIOD OF OCCASIONAL SHOWERS THROUGH MOST OF THE UPCOMING WEEK AS THE LOW SLOWLY TRACKS ACROSS THE REGION WITH RAINFALL TOTALS BETWEEN 2.5 INCHES AND 3 INCHES...WITH HALF OR MORE OF THAT TOTAL FALLING FROM TONIGHT THROUGH MONDAY NIGHT. MARINE... THE SMALL CRAFT ADVISORY IS IN EFFECT UNTIL LATE TUESDAY AFTERNOON FOR ALL NEARSHORE ZONES AS EAST WINDS WILL CONTINUE TO INCREASE TO 15 TO 25 KNOTS...WITH GUSTS UP TO 30 KNOTS BY TONIGHT THROUGH MONDAY...AS LOW PRESSURE SLOWLY APPROACHES THE REGION. THERE WILL BE SOME MOMENTUM TRANSFER THROUGH THE INVERSION OVER THE STABLE WATER FOR A FEW GUSTS TO HIT GALE FORCE LEVELS...BUT NOT FREQUENT ENOUGH TO RAISE THE HEADLINE TO A GALE WARNING AT THIS TIME...THOUGH LATER SHIFTS WILL HAVE TO MONITOR. THE PERSISTENT EAST WINDS WILL BUILD WAVES TO 6 TO 10 FEET BY LATE TONIGHT AND HOLD THEM THERE THROUGH MONDAY. WINDS WILL SLOWLY LOWER LATE MONDAY INTO TUESDAY AS THE SURFACE PRESSURE GRADIENT RELAXES WITH THE LOW MOVING INTO THE WESTERN GREAT LAKES. WAVES WILL SLOWLY SUBSIDE WITH THE EASING WINDS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 4 PM CDT TUESDAY FOR LMZ643>646. && $$ UPDATE...WOOD TODAY/TONIGHT AND AVIATION/MARINE...REM MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
649 AM CDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 PM CDT SUN APR 27 2014 BEGINNING TO FEEL THE AFFECTS OF DEEP LOW PRESSURE CENTERED IN NEW MEXICO WITH BANDS OF ELEVATED THUNDERSTORMS ACROSS THE REGION FROM KABR TO KDVN AND HEADING FOR THE FORECAST AREA. TRIED TO MAKE SOME TIMING IMPROVEMENTS TO THE PRECIPITATION TODAY...AND THEN SOME LARGER CHANGES TO OVERNIGHT RAINFALL TOTALS /UP IN THE WEST BY .3 TO .5 INCHES/...BUT MUCH OF TONIGHTS FORECAST LEFT AS WAS. GOES WATER VAPOR IMAGERY SHOWING A DEEP LOW WITH TROPOPAUSE FOLD DOWN TO 700 MB OVER NEW MEXICO PER RAP TROP ANALYSIS. SURFACE PRESSURE CONTINUES TO FALL ACROSS SD/MN /1 MB PER HOUR/ INCREASING THE PRESSURE GRADIENT...AND WINDS ARE RESPONDING WITH 25 MPH GUSTS TO 35 MPH ALREADY TONIGHT IN EASTERLY FLOW. SURFACE LOW PRESSURE NOW CENTERED IN NERN CO TO WRN NE AT 986 MB. SURFACE WARM SECTOR CONTINUING TO MOISTEN WITH 60F DEWPOINT LINE NOW INTO NEB. NORTH OF THE W-E FRONT NEAR OMAHA-KSTL LINE...DEWPOINTS CONTINUE TO FALL IN STRONG DRIER EASTERLY FLOW /30S/...PRODUCING SOME FIGHT TO RAIN SHOWERS TO HIT THE SURFACE /NOT THE TSRA THOUGH AS HOURLY 0.25 INCH REPORTS ARE COMMON IN IA/. GOES BLENDED PRECIPITABLE WATER /PW/ HOURLY LOOP SHOWS THE MAIN PLUME OF MOISTURE FOR INFLOW INTO TONIGHTS RAIN IS SHIFTING NORTH THRU OK/AR AT THIS TIME...WITH 1.5 INCH VALUES. ALREADY PRESENT FROM THE DAKOTAS SEWRD INTO IA...A PW AXIS EXISTS OF ABOUT 0.60 INCHES WHICH IS 125-150 PERCENT NORMAL. THIS IS MAINLY MOISTURE ABOVE 700MB /PER 00Z RAOB AT KABR/ AND ALSO CO-LOCATED WITH PRETTY STEEP 500-700MB LAPSE RATES OF 7-8C/KM...WHICH IS WHERE THE RADAR ECHOES HAVE DEVELOPED TONIGHT WITH MOST LIGHTNING. LAPSE RATE GRADIENT RUNS KABR-KMCW WITH MAX OVER NEB AT 06Z. THE LATEST RAP ANALYSIS SHOWS THESE LAPSE RATE STEEPENING AS AN ELEVATED MIXED LAYER MOVES IN FROM THE SOUTH...WHICH PUSHES THE GRADIENT AND DESTABILIZATION INTO THE WESTERN FORECAST AREA BY SUNRISE. LAPSE RATES AND INSTABILITY ARE STILL FORECAST TO REMAIN MAINLY WEST OF THE FORECAST AREA THROUGH TONIGHT. SOME 200 J/KG OF INSTABILITY EXISTS ACROSS THE VERY WESTERN FORECAST AREA SO WE SHOULD SEE A DECREASE IN THE LIGHTNING AS THESE STORMS MOVE NORTH. THESE STORMS ARE LOCATED ON THE NOSE OF THE 750-850MB MOISTURE TRANSPORT AND LLJ CONVERGENCE. KDMX IS 60 KTS FROM THE SOUTH PER RADAR AND KARX 88D SHOWED 40 KTS FROM THE SE...SO NICE CONVERGENCE TO MOIST PLUME ALOFT. LATEST RAP AND LONGER RANGE MODELS AGREE ON MOVING THIS SHOWER AND SCT TSRA REGION NORTHWARD THROUGH THE AREA THIS MORNING WITH TRANSPORT CONVERGENCE. TSRA SHOULD GIVE WAY TO MORE SHRA. THE HRRR AND RAP...AS WELL AS NAM AND GFS...HAVE THE IDEA OF A DECREASE OR LULL IN SHOWERY ACTIVITY THIS AFTERNOON AS TRANSPORT AND MOISTURE ADVECTION SHIFTS NORTHEAST. HAVE BUILT THIS INTO THE RAIN CHANCES...WITH AN INCREASE LATE TODAY AND EVENING AS MAIN MOIST PLUME AND FORCING RETURNS WITH AROUND 1 INCH OF RAIN MOST AREAS. HAVE ONLY BOTTOMED THE RAIN CHANCES OUT TO ABOUT 50 PERCENT THIS AFTERNOON...BUT IT IS A START. WIND ADVISORY IS ON TRACK FOR TODAY ALTHOUGH THE GFS IS MUCH LESS ROBUST WITH WINDS TODAY. FROM CURRENT OBSERVATIONS GUSTING TO 35 MPH WEST OF MISS RIVER AND WITH AN INCREASE IN THE PRESSURE GRADIENT TODAY...WIND ADVISORY LOOKS ON TRACK. KARX 88D HAS 45-50 KTS AT 500M ABOVE THE RADAR AT 08Z. IT COULD BE RATHER GUSTY EAST OF THE RIVER TOO IN WI WITH STRONG WINDS RIGHT ABOVE THE SURFACE AND SOME SHALLOW MIXING THIS AFTERNOON WITHOUT RAIN. GUSTS IN THE 30S ARE IN THE FORECAST...BUT WE MAY NEED TO EXPAND THE ADVISORY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 339 AM CDT SUN APR 27 2014 RAIN BAND CONTINUES TO AFFECT WI AREAS MONDAY MORNING AND A BREAK SEEMS TO OCCUR THEN BEFORE THE WARM FRONT AGAIN BECOMES ACTIVE IN THE AFTERNOON ACROSS THE SOUTH. THIS WILL BE IN RESPONSE TO ANOTHER STRONG SPOKE OF SHORTWAVE ENERGY ROTATING NORTH AROUND THE LONGWAVE TROUGH. SEVERE WEATHER CHANCES REALLY BANK ON INSTABILITY OVER THE AREA /DUH/ AND THE WARM SECTOR/FRONT LOCATION WHICH HAS BEEN FORECAST RIGHT ON THE SOUTHERN FORECAST AREA BORDER OR SOUTH...AND RUNNING W-E. THE SHORTWAVE TROUGH ROTATING NORTHWARD LOOKS TO DEVELOP LIFT AND CLOUDS/RAIN BY MID-DAY MONDAY WHICH DOESNT NOT LEAVE MUCH TIME TO DESTABILIZE. THE LATEST SPC FORECAST HAS SHIFTED THE DAY 2 SLIGHT RISK NORTH TO JUST SOUTH OF KDBQ. THERE SEEMS TO BE SOME ELEVATED INSTABILITY NORTH OF THE FRONT IN THE SOUTHERN FORECAST AREA FOR SOME STRONG LOW-TOPPED STORMS. WIND SHEAR IS FAIR SO DYNAMIC LIFT WILL HAVE TO ASSIST TO INVIGORATE THE STORMS...BUT OVERALL THE THREAT SEEMS LOW BUT POSSIBLE...WITH MARGINAL WIND/HAIL. IF THE FRONT SHOULD MOVE INTO THE AREA...SOME LOW-LEVEL VORTICITY WOULD BE AVAILABLE...WHICH WOULD MAKE AN ISOLATED TORNADO POSSIBLE. AT THIS TIME...THE FRONT SEEMS CLOSE BUT NOT INTO THE AREA. WILL CONTINUE TO MENTION THE LIMITED THREAT ACROSS OUR SOUTHERN AREA MONDAY AFTERNOON/EVENING. MORE RAIN AGAIN AS THIS SHORTWAVE TROUGH MOVES NORTH AND ANOTHER THEN FOLLOW BEHIND FOR TUESDAY. THE LOW BEGINS TO SHIFT EAST ENHANCING THE DEFORMATION ON THE NORTH SIDE...SO ANOTHER INCH IS POSSIBLE AGAIN MONDAY NIGHT AND TUESDAY. OVERALL...SREF RUNS ARE CONSISTENT IN SHOWING 2-2.5 INCHES STORM TOTAL ACROSS THE AREA /MEAN/ WITH LITTLE SPREAD IN THE MEMBERS SURPRISINGLY. THIS IS OUR CURRENT FORECAST RAINFALL. SEE HYDROLOGY SECTION FOR IMPACTS ON RIVERS. WEDNESDAY THROUGH SATURDAY...A COOL AND SHOWERY WEEK UNDER THE INFLUENCE OF THE DEEP OCCLUDED LOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 649 AM CDT SUN APR 27 2014 STRONG EAST WINDS AND PERIODS OF SHOWERS ARE EXPECTED AT THE TAF SITES TODAY INTO TONIGHT. THE MAIN CONCERN THIS MORNING IS LOW LEVEL WINDS SHEAR BEFORE SURFACE WINDS INCREASE LATER THIS MORNING. EAST/SOUTHEAST WINDS INCREASE TO AROUND 50 KTS AT 1500 FT...CREATING LLWS AT KLSE. EASTERLY SURFACE WINDS WILL INCREASE INTO THE 25 TO 30 KT RANGE TODAY WITH GUSTS AROUND 39 KTS POSSIBLE. THE STRONGEST WINDS WILL OCCUR AT KRST. WIDESRPEAD SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TONIGHT AS LOW PRESSURE EDGES EAST OUT OF THE CENTRAL PLAINS. MVFR CONDITIONS ARE POSSIBLE IN THE HEAVIER RAIN SHOWERS TONIGHT. SHOWERS AND STRONG EASTERLY WINDS WILL PERSIST THROUGH MUCH OF THE OVERNIGHT HOURS. && .HYDROLOGY... ISSUED AT 339 AM CDT SUN APR 27 2014 WITH VALUES STILL IN THE 2-3 INCH RANGE FOR STORM TOTAL PRECIPITATION THROUGH TUESDAY...FLOODING ON AREA RIVERS IS STILL QUITE POSSIBLE. REVIEWING THE FORECASTS FOR THE CURRENT 72-HOUR RAINFALL AND ITS AFFECT ON RIVERS...THE RIVERS RESPOND BY RISING TO/NEAR MINOR FLOOD STAGE AT MANY SITES. THE DAY SHIFT TODAY WILL REVIEW THE INFORMATION AND ARE CONSIDERING...IN COOPERATION WITH THE RIVER FORECAST CENTER...PLACING THE 72 HOUR RAIN INTO THE ACTUAL FORECASTS. RECALL THE POSTED FORECASTS THAT ARE ISSUED ONLY USE 24 HOUR FORECAST RAINFALL. IN HIGHER CONFIDENCE SITUATIONS LIKE THIS EVENT...IT WOULD BE BETTER TO HAVE THAT 72 HOUR TOTAL INCLUDED. HOWEVER...USERS OF RIVER DATA CAN GO TO THE LINK BELOW TO SEE 72 HOUR RAINFALL RIVER HYDROGRAPHS AT ANY TIME /ALL LOWER CASE AND SCROLL TO BOTTOM OF PAGE/... WWW.CRH.NOAA.GOV/CRH/RFC/MAPGRAPHICALDISPLAY.PHP WILL HOLD OFF FROM ISSUING A FLOOD WATCH AS THE DAY SHIFT WILL HAVE TO VISIT THIS TOPIC WITH THE 72 HOUR RAINFALL RIVER && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ086-087-094-095. IA...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ008>010-018-019- 029. && $$ SHORT TERM...BAUMGARDT LONG TERM...BAUMGARDT AVIATION...WETENKAMP HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CDT SUN APR 27 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 PM CDT SUN APR 27 2014 BEGINNING TO FEEL THE AFFECTS OF DEEP LOW PRESSURE CENTERED IN NEW MEXICO WITH BANDS OF ELEVATED THUNDERSTORMS ACROSS THE REGION FROM KABR TO KDVN AND HEADING FOR THE FORECAST AREA. TRIED TO MAKE SOME TIMING IMPROVEMENTS TO THE PRECIPITATION TODAY...AND THEN SOME LARGER CHANGES TO OVERNIGHT RAINFALL TOTALS /UP IN THE WEST BY .3 TO .5 INCHES/...BUT MUCH OF TONIGHTS FORECAST LEFT AS WAS. GOES WATER VAPOR IMAGERY SHOWING A DEEP LOW WITH TROPOPAUSE FOLD DOWN TO 700 MB OVER NEW MEXICO PER RAP TROP ANALYSIS. SURFACE PRESSURE CONTINUES TO FALL ACROSS SD/MN /1 MB PER HOUR/ INCREASING THE PRESSURE GRADIENT...AND WINDS ARE RESPONDING WITH 25 MPH GUSTS TO 35 MPH ALREADY TONIGHT IN EASTERLY FLOW. SURFACE LOW PRESSURE NOW CENTERED IN NERN CO TO WRN NE AT 986 MB. SURFACE WARM SECTOR CONTINUING TO MOISTEN WITH 60F DEWPOINT LINE NOW INTO NEB. NORTH OF THE W-E FRONT NEAR OMAHA-KSTL LINE...DEWPOINTS CONTINUE TO FALL IN STRONG DRIER EASTERLY FLOW /30S/...PRODUCING SOME FIGHT TO RAIN SHOWERS TO HIT THE SURFACE /NOT THE TSRA THOUGH AS HOURLY 0.25 INCH REPORTS ARE COMMON IN IA/. GOES BLENDED PRECIPITABLE WATER /PW/ HOURLY LOOP SHOWS THE MAIN PLUME OF MOISTURE FOR INFLOW INTO TONIGHTS RAIN IS SHIFTING NORTH THRU OK/AR AT THIS TIME...WITH 1.5 INCH VALUES. ALREADY PRESENT FROM THE DAKOTAS SEWRD INTO IA...A PW AXIS EXISTS OF ABOUT 0.60 INCHES WHICH IS 125-150 PERCENT NORMAL. THIS IS MAINLY MOISTURE ABOVE 700MB /PER 00Z RAOB AT KABR/ AND ALSO CO-LOCATED WITH PRETTY STEEP 500-700MB LAPSE RATES OF 7-8C/KM...WHICH IS WHERE THE RADAR ECHOES HAVE DEVELOPED TONIGHT WITH MOST LIGHTNING. LAPSE RATE GRADIENT RUNS KABR-KMCW WITH MAX OVER NEB AT 06Z. THE LATEST RAP ANALYSIS SHOWS THESE LAPSE RATE STEEPENING AS AN ELEVATED MIXED LAYER MOVES IN FROM THE SOUTH...WHICH PUSHES THE GRADIENT AND DESTABILIZATION INTO THE WESTERN FORECAST AREA BY SUNRISE. LAPSE RATES AND INSTABILITY ARE STILL FORECAST TO REMAIN MAINLY WEST OF THE FORECAST AREA THROUGH TONIGHT. SOME 200 J/KG OF INSTABILITY EXISTS ACROSS THE VERY WESTERN FORECAST AREA SO WE SHOULD SEE A DECREASE IN THE LIGHTNING AS THESE STORMS MOVE NORTH. THESE STORMS ARE LOCATED ON THE NOSE OF THE 750-850MB MOISTURE TRANSPORT AND LLJ CONVERGENCE. KDMX IS 60 KTS FROM THE SOUTH PER RADAR AND KARX 88D SHOWED 40 KTS FROM THE SE...SO NICE CONVERGENCE TO MOIST PLUME ALOFT. LATEST RAP AND LONGER RANGE MODELS AGREE ON MOVING THIS SHOWER AND SCT TSRA REGION NORTHWARD THROUGH THE AREA THIS MORNING WITH TRANSPORT CONVERGENCE. TSRA SHOULD GIVE WAY TO MORE SHRA. THE HRRR AND RAP...AS WELL AS NAM AND GFS...HAVE THE IDEA OF A DECREASE OR LULL IN SHOWERY ACTIVITY THIS AFTERNOON AS TRANSPORT AND MOISTURE ADVECTION SHIFTS NORTHEAST. HAVE BUILT THIS INTO THE RAIN CHANCES...WITH AN INCREASE LATE TODAY AND EVENING AS MAIN MOIST PLUME AND FORCING RETURNS WITH AROUND 1 INCH OF RAIN MOST AREAS. HAVE ONLY BOTTOMED THE RAIN CHANCES OUT TO ABOUT 50 PERCENT THIS AFTERNOON...BUT IT IS A START. WIND ADVISORY IS ON TRACK FOR TODAY ALTHOUGH THE GFS IS MUCH LESS ROBUST WITH WINDS TODAY. FROM CURRENT OBSERVATIONS GUSTING TO 35 MPH WEST OF MISS RIVER AND WITH AN INCREASE IN THE PRESSURE GRADIENT TODAY...WIND ADVISORY LOOKS ON TRACK. KARX 88D HAS 45-50 KTS AT 500M ABOVE THE RADAR AT 08Z. IT COULD BE RATHER GUSTY EAST OF THE RIVER TOO IN WI WITH STRONG WINDS RIGHT ABOVE THE SURFACE AND SOME SHALLOW MIXING THIS AFTERNOON WITHOUT RAIN. GUSTS IN THE 30S ARE IN THE FORECAST...BUT WE MAY NEED TO EXPAND THE ADVISORY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 339 AM CDT SUN APR 27 2014 RAIN BAND CONTINUES TO AFFECT WI AREAS MONDAY MORNING AND A BREAK SEEMS TO OCCUR THEN BEFORE THE WARM FRONT AGAIN BECOMES ACTIVE IN THE AFTERNOON ACROSS THE SOUTH. THIS WILL BE IN RESPONSE TO ANOTHER STRONG SPOKE OF SHORTWAVE ENERGY ROTATING NORTH AROUND THE LONGWAVE TROUGH. SEVERE WEATHER CHANCES REALLY BANK ON INSTABILITY OVER THE AREA /DUH/ AND THE WARM SECTOR/FRONT LOCATION WHICH HAS BEEN FORECAST RIGHT ON THE SOUTHERN FORECAST AREA BORDER OR SOUTH...AND RUNNING W-E. THE SHORTWAVE TROUGH ROTATING NORTHWARD LOOKS TO DEVELOP LIFT AND CLOUDS/RAIN BY MID-DAY MONDAY WHICH DOESNT NOT LEAVE MUCH TIME TO DESTABILIZE. THE LATEST SPC FORECAST HAS SHIFTED THE DAY 2 SLIGHT RISK NORTH TO JUST SOUTH OF KDBQ. THERE SEEMS TO BE SOME ELEVATED INSTABILITY NORTH OF THE FRONT IN THE SOUTHERN FORECAST AREA FOR SOME STRONG LOW-TOPPED STORMS. WIND SHEAR IS FAIR SO DYNAMIC LIFT WILL HAVE TO ASSIST TO INVIGORATE THE STORMS...BUT OVERALL THE THREAT SEEMS LOW BUT POSSIBLE...WITH MARGINAL WIND/HAIL. IF THE FRONT SHOULD MOVE INTO THE AREA...SOME LOW-LEVEL VORTICITY WOULD BE AVAILABLE...WHICH WOULD MAKE AN ISOLATED TORNADO POSSIBLE. AT THIS TIME...THE FRONT SEEMS CLOSE BUT NOT INTO THE AREA. WILL CONTINUE TO MENTION THE LIMITED THREAT ACROSS OUR SOUTHERN AREA MONDAY AFTERNOON/EVENING. MORE RAIN AGAIN AS THIS SHORTWAVE TROUGH MOVES NORTH AND ANOTHER THEN FOLLOW BEHIND FOR TUESDAY. THE LOW BEGINS TO SHIFT EAST ENHANCING THE DEFORMATION ON THE NORTH SIDE...SO ANOTHER INCH IS POSSIBLE AGAIN MONDAY NIGHT AND TUESDAY. OVERALL...SREF RUNS ARE CONSISTENT IN SHOWING 2-2.5 INCHES STORM TOTAL ACROSS THE AREA /MEAN/ WITH LITTLE SPREAD IN THE MEMBERS SURPRISINGLY. THIS IS OUR CURRENT FORECAST RAINFALL. SEE HYDROLOGY SECTION FOR IMPACTS ON RIVERS. WEDNESDAY THROUGH SATURDAY...A COOL AND SHOWERY WEEK UNDER THE INFLUENCE OF THE DEEP OCCLUDED LOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1155 PM CDT SAT APR 26 2014 DRY EASTERLY WINDS CONTINUE TO SLOW THE LOWERING OF CLOUDS ACROSS THE AREA. THIS LOOKS TO CONTINUE OVERNIGHT...THUS SLOWED THE LOWERING OF THE CLOUDS TO MVFR AT KRST FROM 27.11Z TO 27.21Z. THIS MAY HAVE TO SLOWED A BIT MORE INTO SUNDAY EVENING. MEANWHILE KLSE SHOULD BE FAR ENOUGH EAST TO KEEP VFR CONDITIONS THERE THROUGH AT LEAST 28.04Z. SUB CLOUD EVAPORATION SHOULD HELP BRING THE STRONGER WINDS FROM ALOFT TO THE SURFACE OVERNIGHT. AS A RESULT...INCREASED THE WIND GUSTS UP INTO THE 25 TO 30 KNOT RANGE. ON SUNDAY...IT STILL LOOKS LIKE A TIGHT PRESSURE GRADIENT AHEAD OF THE APPROACHING LOW WILL PRODUCE SUSTAINED WINDS IN THE 15 TO 30 KNOT RANGE. IN ADDITION... THE WINDS WILL GUSTS UP TO 35 KNOTS ON SUNDAY. THE HIGHEST WIND GUSTS WILL BE FOUND ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. && .HYDROLOGY... ISSUED AT 339 AM CDT SUN APR 27 2014 WITH VALUES STILL IN THE 2-3 INCH RANGE FOR STORM TOTAL PRECIPITATION THROUGH TUESDAY...FLOODING ON AREA RIVERS IS STILL QUITE POSSIBLE. REVIEWING THE FORECASTS FOR THE CURRENT 72-HOUR RAINFALL AND ITS AFFECT ON RIVERS...THE RIVERS RESPOND BY RISING TO/NEAR MINOR FLOOD STAGE AT MANY SITES. THE DAY SHIFT TODAY WILL REVIEW THE INFORMATION AND ARE CONSIDERING...IN COOPERATION WITH THE RIVER FORECAST CENTER...PLACING THE 72 HOUR RAIN INTO THE ACTUAL FORECASTS. RECALL THE POSTED FORECASTS THAT ARE ISSUED ONLY USE 24 HOUR FORECAST RAINFALL. IN HIGHER CONFIDENCE SITUATIONS LIKE THIS EVENT...IT WOULD BE BETTER TO HAVE THAT 72 HOUR TOTAL INCLUDED. HOWEVER...USERS OF RIVER DATA CAN GO TO THE LINK BELOW TO SEE 72 HOUR RAINFALL RIVER HYDROGRAPHS AT ANY TIME /ALL LOWER CASE AND SCROLL TO BOTTOM OF PAGE/... WWW.CRH.NOAA.GOV/CRH/RFC/MAPGRAPHICALDISPLAY.PHP WILL HOLD OFF FROM ISSUING A FLOOD WATCH AS THE DAY SHIFT WILL HAVE TO VISIT THIS TOPIC WITH THE 72 HOUR RAINFALL RIVER FORECASTS TODAY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR MNZ086-087-094-095. IA...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR IAZ008>010-018-019-029. && $$ SHORT TERM...BAUMGARDT LONG TERM...BAUMGARDT AVIATION...BOYNE HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1155 PM CDT SAT APR 26 2014 .UPDATE... ISSUED AT 1001 PM CDT SAT APR 26 2014 LATEST KARX RADAR...SHOWING A BAND OF PRECIPITATION MOVING NORTHEAST THROUGH PARTS OF SOUTHEAST MINNESOTA AND WEST CENTRAL WISCONSIN. THIS WAS ASSOCIATED WITH STRONG 700 TO 500 MB FRONOTOGENESIS. THE RAP AND NAM SHOW THAT THIS FORCING WILL SHIFT ALONG AND NORTH OF INTERSTATE 90 THROUGH 27.09Z AND THEN WEAKENS IT. THIS SEEMS TO MATCH THE PRECIPITATION THAT SHOWS UP IN THE MESO MODELS...SO TRENDED THE HIGHEST PRECIPITATION CHANCES THROUGH 27.09Z TO BETTER MATCH THEM. AFTER 27.09Z...THE PRECIPITATION CHANCES DRAMATICALLY INCREASE ACROSS SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN. THIS IS WHEN THE BEST 850 MB MOISTURE TRANPSORT IS MOVING INTO THIS AREA AND THE DEVELOPMENT OF STRONG 900 TO 800 MB FRONTOGENESIS. && .SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT) ISSUED AT 343 PM CDT SAT APR 26 2014 RAIN AND WIND ARE THE MAIN CONCERNS THROUGH SUNDAY NIGHT. CURRENT ANALYSIS SHOWS NOSE OF HIGH PRESSURE OVER HUDSONS BAY EXTENDING SOUTHWARD INTO WI WHILE STRENGTHENING CYCLOGENESIS WAS TAKING PLACE ON THE FRONT RANGE OF THE COLORADO ROCKIES. HIGH/MID CLOUDS IN BROAD ISENTROPIC LIFT AHEAD OF THE LOW WAS SPREADING EASTWARD INTO THE AREA. OTHERWISE...TEMPERATURES ACROSS THE AREA THIS AFTERNOON RANGED FROM AROUND THE 50 DEGREE MARK ACROSS NORTH CENTRAL WI...TO THE 60 DEGREE MARK ACROSS PORTIONS OF SOUTHEAST MN/NORTHEAST IA/FAR SOUTHWEST WI. WATER VAPOR SHOWS A POTENT MID/UPPER LEVEL TROUGH PUSHING TOWARD THE 4-CORNERS AREA. THIS WILL LEAD TO FURTHER INTENSIFICATION OF THE SURFACE LOW AS IT MOVES INTO THE PLAINS TONIGHT. INCREASING 850- 700MB MOISTURE TRANSPORT AHEAD OF THE LOW AND STRENGTHENING MID- LEVEL FRONTOGENESIS VICINITY OF THE I-94 CORRIDOR OF MN INTO WESTERN WI WILL LIKELY PRODUCE INCREASING BAND OF ACCAS AND SHOWERS THIS EVENING WITH SHOWERS EXPECTED TO FILL IN FROM THE SOUTHWEST AS WELL IN EASTERN PERIPHERY OF THE AXIS OF MOISTURE TRANSPORT/LIFT. CANNOT RULE OUT SOME EMBEDDED THUNDERSTORMS WITH SOME ELEVATED MUCAPE INCREASING INTO THE 250-500J/KG RANGE AFTER MIDNIGHT PER THE NAM. PLAN ON LOW TEMPERATURES TONIGHT IN THE MIDDLE 30S NORTH OF I- 94...TO THE LOWER 40S ELSEWHERE. WITH TEMPERATURES HOVERING NERVOUSLY CLOSE TO THE FREEZING MARK ACROSS TAYLOR COUNTY...MAY ALSO HAVE TO WATCH CLOSELY FOR THE OUTSIDE CHANCE OF SOME FREEZING RAIN THERE AND POINTS NORTH. PLAN ON SHOWERS THROUGH SUNDAY ALONG WITH THE CHANCE OF ISOLATED- SCATTERED THUNDER FOR AREAS MAINLY ALONG AND SOUTH OF I-90. IT WILL BE WINDY AS WELL ACROSS THE AREA AS THE PRESSURE GRADIENT TIGHTENS SIGNIFICANTLY BETWEEN THE HUDSON BAY HIGH AND DEEPENING LOW PRESSURE MOVING INTO THE CENTRAL PLAINS. EAST WINDS LOOK TO PICK UP INTO THE 20-30 MPH SUSTAINED RANGE WITH WIND GUSTS WEST OF THE RIVER IN THE WIND-PRONE AREAS OF SOUTHEAST MN/NORTHEAST IA 40-45 MPH. FOR THIS REASON...OPTED TO HOIST A WIND ADVISORY FOR THOSE MORE WIND-PRONE AREAS FROM 9AM-9PM SUNDAY. BOTTOM LINE...WILL BE A RAW DAY IN GENERAL WITH HIGHS ONLY IN THE MID 40 TO LOWER 50S COMBINED WITH THE WIND AND SHOWERS. SURFACE LOW LINKS UP WITH THE MID/UPPER LEVEL CLOSED LOW IN THE CENTRAL PLAINS SUNDAY NIGHT WITH AXIS OF DEEP MOISTURE TRANSPORT TAPPING THE GULF OF MEXICO FOCUSING RIGHT INTO THE AREA FOR MORE SHOWERS. AS A RESULT...HEAVIEST RAINFALL AMOUNTS EXPECTED IN THIS PERIOD AS PRECIPITABLE WATER VALUES INCREASE INTO THE 1-1.5 INCH RANGE. THE BEST INSTABILITY FOR THUNDER LOOKS TO FOCUSED MAINLY ALONG/SOUTH OF THE I-90 CORRIDOR ONCE AGAIN. IN FACT...THE 26.12Z ECMWF SHOWING SOME 750-1000J/KG ELEVATED MUCAPE NOSING TOWARD PORTIONS OF NORTHEAST IA BY 12Z MONDAY. WILL HAVE TO KEEP AN EYE ON THIS FOR THE POSSIBILITY OF A FEW HAIL PRODUCING STORMS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 343 PM CDT SAT APR 26 2014 FOR SUNDAY NIGH THROUGH TUESDAY... THE CLOSED LOW AMBLES ITS WAY INTO IA DURING THE DAY MONDAY WITH MAIN FOCUS OF MOISTURE TRANSPORT ON A WEAKENING TREND AND SHIFTING MAINLY NORTHEAST OF I-94. WILL BE WATCHING AREAS ACROSS NORTHEAST IA/FAR SOUTHWEST WI MONDAY AFTN/EVE AS THIS AREA GETS VERY CLOSE TO SOME CLEARING/DESTABILIZATION AHEAD OF THE CLOSED LOW. NAM SHOWING MUCAPE INCREASING INTO THE 600-1100J/KG RANGE WITH 0-6KM BULK SHEAR IN THE 30-40KT RANGE FOR THE POSSIBILITY OF A FEW SEVERE THUNDERSTORMS. OTHERWISE...LOOK FOR A PRETTY DECENT TEMPERATURE GRADIENT ACROSS THE AREA...RANGING FROM THE MIDDLE/UPPER 40S NORTHEAST OF I-94...TO THE UPPER 50S/A FEW LOWER 60S ACROSS PORTION OF NORTHEAST IA INTO FAR SOUTHWEST WI. LOOK FOR SHOWERS TO CONTINUE MONDAY NIGHT THROUGH TUESDAY WITH NAM/GFS/ECMWF/GEM ALL SHOWING TROWAL SIGNATURE MOISTURE WRAPPING INTO THE AREA NORTH OF THE CLOSED LOW AS IT LIFTS OUT OF IA AND ALONG THE IA/WI BORDER. HIGHS ON TUESDAY WILL BE STUCK IN THE MIDDLE/UPPER 40S NORTHEAST OF I-94...TO THE UPPER 50S ACROSS PORTION OF NORTHEAST IA INTO FAR SOUTHWEST WI. FOR WEDENESDAY THROUGH SATURDAY... COOL/SHOWERY PERIOD CONTINUES THROUGH THE PERIOD AS THE CLOSED LOW CAMPS OUT OVER THE GREAT LAKES/UPPER MISSISSIPPI RIVER REGION. RAINFALL DOES LOOK TO BE ON THE LIGHTER SIDE THOUGH...BUT SHOWERY AND COOLER THAN NORMAL NONETHELESS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1155 PM CDT SAT APR 26 2014 DRY EASTERLY WINDS CONTINUE TO SLOW THE LOWERING OF CLOUDS ACROSS THE AREA. THIS LOOKS TO CONTINUE OVERNIGHT...THUS SLOWED THE LOWERING OF THE CLOUDS TO MVFR AT KRST FROM 27.11Z TO 27.21Z. THIS MAY HAVE TO SLOWED A BIT MORE INTO SUNDAY EVENING. MEANWHILE KLSE SHOULD BE FAR ENOUGH EAST TO KEEP VFR CONDITIONS THERE THROUGH AT LEAST 28.04Z. SUB CLOUD EVAPORATION SHOULD HELP BRING THE STRONGER WINDS FROM ALOFT TO THE SURFACE OVERNIGHT. AS A RESULT...INCREASED THE WIND GUSTS UP INTO THE 25 TO 30 KNOT RANGE. ON SUNDAY...IT STILL LOOKS LIKE A TIGHT PRESSURE GRADIENT AHEAD OF THE APPROACHING LOW WILL PRODUCE SUSTAINED WINDS IN THE 15 TO 30 KNOT RANGE. IN ADDITION... THE WINDS WILL GUSTS UP TO 35 KNOTS ON SUNDAY. THE HIGHEST WIND GUSTS WILL BE FOUND ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. && .HYDROLOGY... ISSUED AT 343 PM CDT SAT APR 26 2014 WITH TOTAL RAINFALL THROUGH TUESDAY NEARING 2 INCHES...EXPECT RISES ON AREA RIVERWAYS. IN FACT...CONFIDENCE IS FAIRLY HIGH THIS RAINFALL WILL PUSH A FEW AREA RIVERS TO NEAR FLOOD STAGE SUCH AS THE KICKAPOO...TURKEY...UPPER IOWA RIVERWAYS. THE MISSISSIPPI WILL REMAIN HIGH BUT REMAINING BELOW FLOOD STAGE AT THIS POINT. SHOULD HEAVIER RAIN MATERIALIZE WITH SAY ANOTHER 1 INCH OR MORE OCCURRING THROUGH TUESDAY...SOME MINOR-MODERATE FLOODING COULD RESULT. CONSIDERED A FLOOD WATCH FOR MONDAY NIGHT THROUGH WEDNESDAY...BUT THERE IS STILL CONSIDERABLE UNCERTAINTY ON PLACEMENT AND AMOUNT OF RAIN. WILL THEREFORE HOLD OFF FOR NOW AND PASS ALONG TO THE NIGHT SHIFT TO ASSESS WITH HOPEFULLY BETTER MODEL RESOLUTION. FEELING RIGHT NOW IS THIS IS NOT A QUICK RESPONSE/FLASHY SITUATION GIVEN LOWER INSTABILITY PARAMETERS FOR LOCALIZED HEAVY RAIN FROM THUNDERSTORMS. WILL THEREFORE CONTINUE HYDROLOGIC ESF STATEMENTS FOR NOW. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WIND ADVISORY FROM 9 AM TO 9 PM CDT SUNDAY FOR MNZ086-087-094- 095. IA...WIND ADVISORY FROM 9 AM TO 9 PM CDT SUNDAY FOR IAZ008>010-018- 019-029. && $$ UPDATE...BOYNE SHORT TERM...DAS LONG TERM....DAS AVIATION...BOYNE HYDROLOGY....DAS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
740 PM MDT MON APR 28 2014 .UPDATE... ISSUED AT 728 PM MDT MON APR 28 2014 UPDATED POP...TEMPERATURES...AND WINDS THROUGH TUESDAY AS A STRONG CLOSED LOW ALOFT OVER KANSAS/NEBRASKA WILL MOVE VERY LITTLE OVER THE NEXT 24 HOURS. A STRONG DISTURBANCE WILL ROTATE COUNTERCLOCKWISE AROUND THIS LOW AND MOVE OVER THE FORECAST AREA TOMORROW. EXPECT VERY SIMILAR CONDITIONS ON TUESDAY COMPARED TO TODAY...WITH STRONG WINDS ACROSS THE HIGH PLAINS AND A BETTER CHANCE FOR SCATTERED TO NUMEROUS SNOW/RAIN SHOWERS...ESPECIALLY IN THE AFTERNOON. HEAVY SNOW SHOWERS CAN NOT BE RULED OUT WITH VISIBILITIES BRIEFLY LOWERING TO ONE QUARTER MILE OR LESS AT TIMES. TEMPERATURES WILL STRUGGLE TO REACH THE LOW TO MID 40S AGAIN...AS NORTHERLY WINDS GUST TO NEAR 60 MPH OVER PORTIONS OF THE HIGH PLAINS AND RIDGES. DECIDED TO EXTEND THE HIGH WIND WARNING FOR THE SOUTHERN PANHANDLE INTO TUESDAY AFTERNOON. ALTHOUGH GUSTS OVER 58 MPH ARE NOT EXPECTED TONIGHT...DECIDED THE DURATION OF ANY LULL IN THE WINDS TO BE RELATIVELY SHORT IN DURATION TO EXPIRE THE CURRENT HEADLINE. MIDNIGHT SHIFT MAY HAVE TO EXTEND THIS WARNING FURTHER WEST OR NORTH...SINCE CURRENT MODELS ARE SHOWING SLIGHTLY STRONGER WINDS COMPARED TO TODAY. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 247 PM MDT MON APR 28 2014 MAIN CONCERN THIS PERIOD WILL CONTINUE TO BE WINDS AS THEY WILL REMAIN RATHER STRONG THOUGH WEDNESDAY...ESPECIALLY OVER THE PLAINS. IN THE IMMEDIATE SHORT-TERM CURRENT ADVY/HI WIND HILITES LOOK FINE OVER MOST OF THE PANHANDLE AND WILL KEEP UP INTO THIS EVENING...HOWEVER WILL TRIM OUT DAWES AND BOX BUTTE COUNTIES AS WINDS HAVE DROPPED OFF THERE. UPPER LOW OVER NEB WILL DRIFT ONLY SLOWLY EASTWARD OR MEANDER THROUGH WEDS WITH STRONG MID-LEVEL WINDS MIXING DOWN TO THE SURFACE BOTH AFTERNOONS. BIG DILEMMA IS HOW MUCH. CLOUDS AND PCPN WILL TEND TO LIMIT MIXING SOME. PROGGED 800MB WINDS FOR TUESDAY ABOUT THE SAME AS TODAY WHERE MOST AREAS STAYED IN ADVISORY SPEEDS. WILL NEED AT LEAST AN ADVISORY FOR THE PANHANDLE AGAIN TUESDAY AND COULD FLIRT WITH HIGH WIND LEVELS DESPITE SLIGHTLY LESS GRADIENT IF MORE MIXING OCCURS. WILL HOLD OFF ON NEW HILITES FOR NOW... ALLOWING CURRENT ONES TO EXPIRE FIRST. WRAP-AROUND PRECIPITATION WILL ALSO CONTINUE TONIGHT AND TUESDAY THEN SHOULD TREND DOWN TUESDAY NIGHT AND WEDS AS THE UPPER LOW DRIFTS FARTHER AWAY AND A SOMEWHAT DRIER NORTHERLY FLOW OCCURS OVER THE AREA. SOME LIGHT SNOW ACCUMULATIONS POSSIBLE OVER THE NORTHERN PANHANDLE TONIGHT THOUGH HIGHER AMOUNTS LOOK TO BE JUST A BIT TO THE EAST. TEMPERATURES REMAINING COOL THROUGH WEDNESDAY. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 247 PM MDT MON APR 28 2014 LATEST WATER VAPOR LOOP WAS SHOWING THE UPPER LEVEL RIDGE BUILDING ACROSS THE PACIFIC NORTHWEST IN RESPONSE TO THE DIGGING UPPER LEVEL TROF OFF THE GULF OF ALASKA. THIS SCENARIO WILL FAVOR RATHER DRY AND COOL CONDITIONS ON THURSDAY. BEYOND THURSDAY...THE UPPER LEVEL PATTERN BEGINS TO FLATTEN OUT SOME WHICH WILL FAVOR MORE UNSETTLED CONDITIONS TOWARDS THE WEEKEND. FRIDAY-SATURDAY: THE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH A WARM UP TAKING PLACE THIS WEEKEND AS 700MB TEMPERATURE STANDARDIZED ANOMALIES APPROACH TO 1 STANDARD DEVIATION. THIS SHOULD ALLOW FOR TEMPERATURES TO CLIMB TO AROUND 70 ON SATURDAY. IT MAY BE A TAD COOLER ACROSS NORTHEAST CORNER OF OUR FORECAST AREA CLOSER TO THE UPPER LEVEL TROF PUSHING DOWN INTO THE NORTHERN PLAINS. A WEAK BOUNDARY IS EXPECTED TO DIVE SOUTHEAST ACROSS THE AREA ON FRIDAY AND MAY BRING A CHANCE OF SHOWERS MAINLY ACROSS AREAS EAST OF THE LARAMIE RANGE FRIDAY MORNING. ELSEWHERE...THERE WILL BE SOME GOOD UPSLOPE FLOW IN THE HIGHER ELEVATIONS WHICH WILL FAVOR SOME SCATTERED RAIN SHOWERS ON FRIDAY. SATURDAY WE MAY SEE MORE OF A THREAT OF SOME SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A BOUNDARY EXTENDING FROM THE SOUTHERN PANHANDLE TO DOUGLAS. THIS AREA MAY ACTUALLY SEE A FEW THUNDERSTORMS DURING THE AFTERNOON WITH CAPE VALUES REACHING 1000J/KG. WE WILL SEE HOW THINGS EVOLVE AS WE APPROACH THE WEEKEND ESPECIALLY WITH REGARDS TO THE POSITION OF THE WAVES. SUNDAY-MONDAY: THE MODELS DO SHOW SOME WEAK UPPER LEVEL RIDGING TAKING PLACE WHICH WILL KEEP OUR TEMPERATURES ON THE MILD SIDE. THE SURFACE LEE TROF MAY ALSO BECOME ESTABLISHED WHICH MAY FAVOR BETTER MOISTURE EAST OF THE LARAMIE RANGE. AS A RESULT...WE MAY SEE A CHANCE OF THUNDERSTORMS EARLY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY AFTERNOON) ISSUED AT 458 PM MDT MON APR 28 2014 STRATUS LIKELY TO MOVE INTO THE KCDR AND KAIA AERODROMES THIS EVENING AND PERSIST INTO TUESDAY MORNING. LATEST HRRR FORECAST DOES SHOW SOME TEMPO IFR CONDITIONS UP THAT WAY FOR A TIME TONIGHT. BIG ISSUE IS WIND...WHICH WILL DIE OFF SLIGHTLY TONIGHT...BUT THEN PICK UP AROUND THE 14Z TIME FRAME TUESDAY. WIND GUSTS OR 45 TO 50KTS LIKELY FOR THE SOUTHERN PANHANDLE AIRPORTS ONCE AGAIN TUESDAY. && .FIRE WEATHER... ISSUED AT 247 PM MDT MON APR 28 2014 NO CONCERNS ANTICIPATED THROUGH THE WEEK WITH TEMPERATURES EXPECTED TO BE COOL TO MILD THROUGH THE MID PART OF THE WEEK THEN WARM SOME BY THE END OF THE WEEK. CONDITIONS WILL REMAIN NON- CRITICAL OUTSIDE OF WINDS WHICH WILL REMAIN RATHER STRONG MAINLY IN THE AFTERNOONS OVER THE PLAINS THROUGH WEDS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR NEZ095-096. HIGH WIND WARNING UNTIL 8 PM MDT TUESDAY FOR NEZ019>021-054-055. && $$ UPDATE...TJT SHORT TERM...RE LONG TERM...REC AVIATION...CLAYCOMB FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1127 AM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 826 AM MDT SUN APR 27 2014 LATEST VISIBLE SATELLITE IMAGERY SHOWING UPPER LEVEL LOW STAYING FARTHER SOUTH THAT THE MODELS INDICATED YESTERDAY...AND THE LOW LOOKS TO BE PUSHING FARTHER EASTWARD TOO. THIS MAKES IT MUCH LESS FAVORABLE TO WIDESPREAD PRECIPITATION ACROSS THE FORECAST AREA TODAY. DRY WEDGE ALREADY WRAPPING NORTHWARDS INTO WESTERN NEBRASKA...WHICH WILL LIKELY CUT OFF THE ONLY MOISTURE SOURCE FOR SOUTHEAST WYOMING. ALSO THUNDERSTORMS ERUPTING ACROSS THE PLAINS DISRUPTING THE MOISTURE THAT WOULD HAVE LIKELY WRAPPED WESTWARD INTO THE AREA. WILL WATCH THE TRENDS OVER THE NEXT SEVERAL HOURS...BUT GENERALLY EXPECTING LESS PRECIPITATION WITH THE FARTHER EAST TRACK OF THE UPPER LOW. STILL...NASTY CONDITIONS WILL CONTINUE OVER THE SUMMIT THROUGH THIS MORNING AND LIKELY INTO EARLY AFTERNOON BEFORE SNOW STARTS TO WIND DOWN IN THAT AREA. UPDATE ISSUED AT 602 AM MDT SUN APR 27 2014 LATEST HRRR CONFIRMS THE TREND OF 06Z DATA POINTING TOWARDS LESS SNOWFALL AMOUNTS ACROSS ELEVATIONS ABOVE 7500 FEET IN SOUTHEAST WYOMING. RADAR RETURNS HAVE NOT BEEN SHOWING THE ENHANCEMENT THAT WAS EARLIER EXPECTED EITHER BY THIS POINT. SO...HAVE OPTED TO DOWNGRADE THE WINTER STORM WARNING TO A WINTER WEATHER ADVISORY. NOT TO SAY ACCUMULATING SNOW WILL NOT FALL TODAY...JUST IN LIGHTER AMOUNTS THAT WAS EARLIER ANTICIPATED. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 AN ACTIVE DAY SHAPING UP AS LOW PRESSURE STACKS OVR CENTRAL NEBRASKA. SATELLITE PIX SHOWS THIS WELL-DEFINED LOW PRESSURE SPINNING ALONG THE CO/NM STATELINE WITH THE LAST FEW FRAMES BEGINNING TO SHOW A NORTHEASTERLY TURN. 08Z SFC ANALYSIS PLACES 986MB LOW JUST TO THE EAST OF THE CWFA...NORTHEAST OF OGALLALA. HAVE SEEN A BREAK PRECIP OVR THE PAST FEW HOURS WITH THE EXCEPTION OF UP TO AN INCH OF NEW SNOW FALLING OVR THE SRN LARAMIE RANGE. HOWEVER...THIS TOO LOOKS SHORT-LIVED AS SHOWERS HAVE BEGAN TO BLOSSOM OVR NRN COLORADO SINCE 0830Z. MODELS ARE ALL SIMILAR IN STACKING THIS STRONG AREA OF LOW PRESSURE ALONG THE NE/KS STATELINES BY 00Z MONDAY. THIS TRACK HAS TRENDED TOWARDS THE SRN SOLUTIONS FROM A FEW DAYS AGO. TWO MAIN CONCERNS FROM THIS STORM TODAY WILL BE THE STRONG WIND POTENTIAL MAINLY THIS AFTERNOON AS WELL AS SNOW ACCUMULATIONS AND SNOW LEVELS. THE SRN TRACK OF THE LOW HAS SHIFTED THE STRONGEST WINDS FARTHER SOUTH THAN EARLIER RUNS HAD SUGGESTED. SO...HAVE CANCELLED THE HIGH WIND WATCH ACROSS CONVERSE/NIOBRARA/GOSHEN/PLATTE COUNTIES. FARTHER SOUTH...THE GFS/NAM STILL HAVE DIFFERING SOLUTIONS WITH THE NAM SIGNIFICANTLY WEAKER THAN THE GFS. A RESULT OF THE NAM SHOWING VERY LITTLE MIXING IN THE BOUNDARY LAYER. COMPARATIVELY...THE GFS IS AS IT USUALLY IS...THE BULLISH OUTLIER WHEN IT COMES TO THE DEPTH OF THE MIXED LAYER AND AVAILABLE WIND SPEEDS AT THE TOP. MEANWHILE... LATEST HRRR OUTPUT SUGGEST GUSTS OF 45-55 MPH FROM CHEYENNE TO SIDNEY BY THIS AFTERNOON. MUCH WILL DEPEND ON HOW OF THE STEEP SUN ANGLE IS ABLE TO MIX THE BOUNDARY LAYER THIS AFTERNOON. HAVE OPTED TO UPGRADE TO A HIGH WIND WARNING FOR LARAMIE...KIMBALL AND CHEYENNE COUNTIES. HOWEVER...IT LOOKS TO BE A FAIRLY MARGINAL EVENT AT THIS POINT. HAVE ALSO ADDED SCOTTS BLUFF...BANNER AND MORRILL COUNTIES TO A WIND ADVISORY. PRECIP HAS BEEN FAIRLY SLOW TO GET GOING THIS MORNING...BUT THIS WILL CHANGE SHORTLY AS IMPRESSIVE POCKET OF QG LIFT MOVES FROM NORTHEAST COLORADO INTO WRN NEBRASKA. SO...EXPECT PRECIP TO BEGIN TO INCREASE THRU THE MORNING. WET BULB ZERO HEIGHTS HAVE ALREADY FALLEN TO AROUND 6500 FEET THIS MORNING AND WITH PRECIPITATION...THESE WILL LIKELY FALL TO AROUND 5500 FEET. SNOW AMOUNTS WILL LIKELY BE ON THE LIGHT SIDE OF WARNING CRITERIA...BUT GIVEN HOW LATE IN THE SEASON IT IS...PLUS THE COMBINATION OF THE STRONG NORTHWEST WINDS...FEEL THE WINTER STORM WARNING IS STILL JUSTIFIED FOR NOW. THIS MAY CHANGE DEPENDING UPON HOW SNOW DEVELOPS THIS MORNING. PRECIPITATION WILL LIFT INTO ERN ZONES FOR THIS EVENING AND TONIGHT. SNOW-LEVELS WILL FALL TO AROUND 4000 FEET TONIGHT...SO SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE EVEN ALONG THE PINE RIDGE. THE UPPER-LOW WILL WOBBLE AROUND IN NEBRASKA ON MONDAY MOVING VERY LITTLE. PRECIPITATION COVERAGE WILL BE LESS ON MONDAY...WHICH WILL ALLOW FOR DEEPER BOUNDARY LAYER MIXING. WILL UNDOUBTEDLY BE STARING AT ANOTHER DAY OF POTENTIAL WIND HIGHLIGHTS...ESPECIALLY OVR PORTIONS OF THE WRN NEBRASKA PANHANDLE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 UNSEASONABLY COOL PATTERN IS STILL SHOWN THROUGH MUCH OF THE EXTENDED PERIOD. NORTHERLY FLOW ALOFT IS OVER THE REGION ON MON NIGHT AND CONTINUES WELL INTO THURS. THIS KEEPS 700MB TEMPS IN THE -6C TO -10C RANGE THROUGH THURS SO HIGHS WILL STRUGGLE TO GET OUT OF THE 40S...ESPECIALLY WITH WIDESPREAD CLOUD COVER. SHORTWAVES PIVOTING SOUTHWARD WILL COMBINE WITH GOOD 700-500MB MOISTURE TO KEEP A CHANCE OF LIGHT SHOWERS GOING MON NIGHT THROUGH WED. NOT EXPECTING ANY TSTMS IN THE STABLE COOL AIRMASS. THE OTHER MAIN STORY THROUGH WED WILL BE THE WINDY CONDITIONS ACROSS THE PLAINS. THE GFS INDICATES NORTHERLY 700MB WINDS OF 35-45 KTS FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE FOR THE ENTIRE PERIOD FROM MON NIGHT INTO THURS MORNING. OF COURSE WINDS WILL COME DOWN DURING THE OVERNIGHT HOURS WITH THE LOSS OF DAYTIME MIXING...HOWEVER MAY GET GUSTS TO ADVISORY CRITERIA OVER THE PANHANDLE AT LEAST ON TUES AFTN. THE GRADIENT WEAKENS BY THURS AND INTO FRI. WILL LIKELY BEGIN TO SEE TEMPS MODERATE ON FRI AND ESPECIALLY INTO SAT AS THE PERSISTENT NORTHERLY FLOW BECOMES MORE ZONAL. NOT SEEING ANY ABOVE AVERAGE TEMPS ANYTIME IN THE LONG TERM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY MORNING) ISSUED AT 1127 AM MDT SUN APR 27 2014 BANDS OF RAIN AND SNOW SHOWERS OVER MUCH OF SE WYOMING INTO THE NEB PANHANDLE WILL PERSIST THIS AFTERNOON WITH WIDESPREAD MVFR/IFR CIGS AND VSBYS. STRONG NW WINDS ALSO WILL OCCUR OVER THE AREA ESPECIALLY EAST OF THE MTNS THROUGH TONIGHT THOUGH EASING SOME THIS EVENING. SOME IMPROVEMENT IN CONDITIONS TONIGHT WITH CIGS RISING TO VFR FROM WEST TO EAST. && .FIRE WEATHER... ISSUED AT 339 AM MDT SUN APR 27 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A LARGE STORM SYSTEM WILL BE STATIONARY OVER THE CENTRAL PLAINS. UNSEASONABLY COOL TEMPERATURES COMBINED WITH WETTING RAINS/SNOWS WILL PREVENT ANY FIRE SPREAD CONCERNS. NORTHWEST WINDS OF 30 TO 50 MPH CAN BE EXPECTED OVER A LARGE PART OF THE DISTRICT HOWEVER DURING THIS PERIOD. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR WYZ118-119. WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ103- 105-110-112-114>117. NE...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR NEZ054-055. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ019>021. && $$ UPDATE...SML SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
840 AM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 826 AM MDT SUN APR 27 2014 LATEST VISIBLE SATELLITE IMAGERY SHOWING UPPER LEVEL LOW STAYING FARTHER SOUTH THAT THE MODELS INDICATED YESTERDAY...AND THE LOW LOOKS TO BE PUSHING FARTHER EASTWARD TOO. THIS MAKES IT MUCH LESS FAVORABLE TO WIDESPREAD PRECIPITATION ACROSS THE FORECAST AREA TODAY. DRY WEDGE ALREADY WRAPPING NORTHWARDS INTO WESTERN NEBRASKA...WHICH WILL LIKELY CUT OFF THE ONLY MOISTURE SOURCE FOR SOUTHEAST WYOMING. ALSO THUNDERSTORMS ERUPTING ACROSS THE PLAINS DISRUPTING THE MOISTURE THAT WOULD HAVE LIKELY WRAPPED WESTWARD INTO THE AREA. WILL WATCH THE TRENDS OVER THE NEXT SEVERAL HOURS...BUT GENERALLY EXPECTING LESS PRECIPITATION WITH THE FARTHER EAST TRACK OF THE UPPER LOW. STILL...NASTY CONDITIONS WILL CONTINUE OVER THE SUMMIT THROUGH THIS MORNING AND LIKELY INTO EARLY AFTERNOON BEFORE SNOW STARTS TO WIND DOWN IN THAT AREA. UPDATE ISSUED AT 602 AM MDT SUN APR 27 2014 LATEST HRRR CONFIRMS THE TREND OF 06Z DATA POINTING TOWARDS LESS SNOWFALL AMOUNTS ACROSS ELEVATIONS ABOVE 7500 FEET IN SOUTHEAST WYOMING. RADAR RETURNS HAVE NOT BEEN SHOWING THE ENHANCEMENT THAT WAS EARLIER EXPECTED EITHER BY THIS POINT. SO...HAVE OPTED TO DOWNGRADE THE WINTER STORM WARNING TO A WINTER WEATHER ADVISORY. NOT TO SAY ACCUMULATING SNOW WILL NOT FALL TODAY...JUST IN LIGHTER AMOUNTS THAT WAS EARLIER ANTICIPATED. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 AN ACTIVE DAY SHAPING UP AS LOW PRESSURE STACKS OVR CENTRAL NEBRASKA. SATELLITE PIX SHOWS THIS WELL-DEFINED LOW PRESSURE SPINNING ALONG THE CO/NM STATELINE WITH THE LAST FEW FRAMES BEGINNING TO SHOW A NORTHEASTERLY TURN. 08Z SFC ANALYSIS PLACES 986MB LOW JUST TO THE EAST OF THE CWFA...NORTHEAST OF OGALLALA. HAVE SEEN A BREAK PRECIP OVR THE PAST FEW HOURS WITH THE EXCEPTION OF UP TO AN INCH OF NEW SNOW FALLING OVR THE SRN LARAMIE RANGE. HOWEVER...THIS TOO LOOKS SHORT-LIVED AS SHOWERS HAVE BEGAN TO BLOSSOM OVR NRN COLORADO SINCE 0830Z. MODELS ARE ALL SIMILAR IN STACKING THIS STRONG AREA OF LOW PRESSURE ALONG THE NE/KS STATELINES BY 00Z MONDAY. THIS TRACK HAS TRENDED TOWARDS THE SRN SOLUTIONS FROM A FEW DAYS AGO. TWO MAIN CONCERNS FROM THIS STORM TODAY WILL BE THE STRONG WIND POTENTIAL MAINLY THIS AFTERNOON AS WELL AS SNOW ACCUMULATIONS AND SNOW LEVELS. THE SRN TRACK OF THE LOW HAS SHIFTED THE STRONGEST WINDS FARTHER SOUTH THAN EARLIER RUNS HAD SUGGESTED. SO...HAVE CANCELLED THE HIGH WIND WATCH ACROSS CONVERSE/NIOBRARA/GOSHEN/PLATTE COUNTIES. FARTHER SOUTH...THE GFS/NAM STILL HAVE DIFFERING SOLUTIONS WITH THE NAM SIGNIFICANTLY WEAKER THAN THE GFS. A RESULT OF THE NAM SHOWING VERY LITTLE MIXING IN THE BOUNDARY LAYER. COMPARATIVELY...THE GFS IS AS IT USUALLY IS...THE BULLISH OUTLIER WHEN IT COMES TO THE DEPTH OF THE MIXED LAYER AND AVAILABLE WIND SPEEDS AT THE TOP. MEANWHILE... LATEST HRRR OUTPUT SUGGEST GUSTS OF 45-55 MPH FROM CHEYENNE TO SIDNEY BY THIS AFTERNOON. MUCH WILL DEPEND ON HOW OF THE STEEP SUN ANGLE IS ABLE TO MIX THE BOUNDARY LAYER THIS AFTERNOON. HAVE OPTED TO UPGRADE TO A HIGH WIND WARNING FOR LARAMIE...KIMBALL AND CHEYENNE COUNTIES. HOWEVER...IT LOOKS TO BE A FAIRLY MARGINAL EVENT AT THIS POINT. HAVE ALSO ADDED SCOTTS BLUFF...BANNER AND MORRILL COUNTIES TO A WIND ADVISORY. PRECIP HAS BEEN FAIRLY SLOW TO GET GOING THIS MORNING...BUT THIS WILL CHANGE SHORTLY AS IMPRESSIVE POCKET OF QG LIFT MOVES FROM NORTHEAST COLORADO INTO WRN NEBRASKA. SO...EXPECT PRECIP TO BEGIN TO INCREASE THRU THE MORNING. WET BULB ZERO HEIGHTS HAVE ALREADY FALLEN TO AROUND 6500 FEET THIS MORNING AND WITH PRECIPITATION...THESE WILL LIKELY FALL TO AROUND 5500 FEET. SNOW AMOUNTS WILL LIKELY BE ON THE LIGHT SIDE OF WARNING CRITERIA...BUT GIVEN HOW LATE IN THE SEASON IT IS...PLUS THE COMBINATION OF THE STRONG NORTHWEST WINDS...FEEL THE WINTER STORM WARNING IS STILL JUSTIFIED FOR NOW. THIS MAY CHANGE DEPENDING UPON HOW SNOW DEVELOPS THIS MORNING. PRECIPITATION WILL LIFT INTO ERN ZONES FOR THIS EVENING AND TONIGHT. SNOW-LEVELS WILL FALL TO AROUND 4000 FEET TONIGHT...SO SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE EVEN ALONG THE PINE RIDGE. THE UPPER-LOW WILL WOBBLE AROUND IN NEBRASKA ON MONDAY MOVING VERY LITTLE. PRECIPITATION COVERAGE WILL BE LESS ON MONDAY...WHICH WILL ALLOW FOR DEEPER BOUNDARY LAYER MIXING. WILL UNDOUBTEDLY BE STARING AT ANOTHER DAY OF POTENTIAL WIND HIGHLIGHTS...ESPECIALLY OVR PORTIONS OF THE WRN NEBRASKA PANHANDLE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 UNSEASONABLY COOL PATTERN IS STILL SHOWN THROUGH MUCH OF THE EXTENDED PERIOD. NORTHERLY FLOW ALOFT IS OVER THE REGION ON MON NIGHT AND CONTINUES WELL INTO THURS. THIS KEEPS 700MB TEMPS IN THE -6C TO -10C RANGE THROUGH THURS SO HIGHS WILL STRUGGLE TO GET OUT OF THE 40S...ESPECIALLY WITH WIDESPREAD CLOUD COVER. SHORTWAVES PIVOTING SOUTHWARD WILL COMBINE WITH GOOD 700-500MB MOISTURE TO KEEP A CHANCE OF LIGHT SHOWERS GOING MON NIGHT THROUGH WED. NOT EXPECTING ANY TSTMS IN THE STABLE COOL AIRMASS. THE OTHER MAIN STORY THROUGH WED WILL BE THE WINDY CONDITIONS ACROSS THE PLAINS. THE GFS INDICATES NORTHERLY 700MB WINDS OF 35-45 KTS FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE FOR THE ENTIRE PERIOD FROM MON NIGHT INTO THURS MORNING. OF COURSE WINDS WILL COME DOWN DURING THE OVERNIGHT HOURS WITH THE LOSS OF DAYTIME MIXING...HOWEVER MAY GET GUSTS TO ADVISORY CRITERIA OVER THE PANHANDLE AT LEAST ON TUES AFTN. THE GRADIENT WEAKENS BY THURS AND INTO FRI. WILL LIKELY BEGIN TO SEE TEMPS MODERATE ON FRI AND ESPECIALLY INTO SAT AS THE PERSISTENT NORTHERLY FLOW BECOMES MORE ZONAL. NOT SEEING ANY ABOVE AVERAGE TEMPS ANYTIME IN THE LONG TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 548 AM MDT SUN APR 27 2014 RADAR SHOWS THE COVERAGE OF RAIN AND SNOW BEGINNING TO INCREASE ACROSS AREAS IN SOUTHEAST WY. KEPT KLAR IN IFR VIS AND LIGHT SNOW THROUGH MID-MORNING. STILL SOME QUESTION AS TO WHETHER RAIN WILL TRANSITION OVER TO SNOW AT KCYS BY LATER THIS MORNING. A LARGE BAND OF LIGHT RAIN IS FCSTED TO DEVELOP OVER MUCH OF THE PANHANDLE BY LATE MORNING AND PERSIST THROUGH THE EVENING. GENERALLY HAVE MVFR CONDITIONS IN THE RAIN OVER THE PANHANDLE...ALTHOUGH BRIEF IFR VIS COULD BE POSSIBLE IF MODERATE RAIN DEVELOPS. NORTHWEST WINDS WILL INCREASE THROUGH THE MORNING WITH WIDESPREAD GUSTS TO 35-45 KTS EXPECTED IN THE AFTERNOON. && .FIRE WEATHER... ISSUED AT 339 AM MDT SUN APR 27 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A LARGE STORM SYSTEM WILL BE STATIONARY OVER THE CENTRAL PLAINS. UNSEASONABLY COOL TEMPERATURES COMBINED WITH WETTING RAINS/SNOWS WILL PREVENT ANY FIRE SPREAD CONCERNS. NORTHWEST WINDS OF 30 TO 50 MPH CAN BE EXPECTED OVER A LARGE PART OF THE DISTRICT HOWEVER DURING THIS PERIOD. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR WYZ118-119. WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ103- 105-110-112-114>117. NE...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR NEZ054-055. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ019>021. && $$ UPDATE...SML SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
607 AM MDT SUN APR 27 2014 .UPDATE... ISSUED AT 602 AM MDT SUN APR 27 2014 LATEST HRRR CONFIRMS THE TREND OF 06Z DATA POINTING TOWARDS LESS SNOWFALL AMOUNTS ACROSS ELEVATIONS ABOVE 7500 FEET IN SOUTHEAST WYOMING. RADAR RETURNS HAVE NOT BEEN SHOWING THE ENHANCEMENT THAT WAS EARLIER EXPECTED EITHER BY THIS POINT. SO...HAVE OPTED TO DOWNGRADE THE WINTER STORM WARNING TO A WINTER WEATHER ADVISORY. NOT TO SAY ACCUMULATING SNOW WILL NOT FALL TODAY...JUST IN LIGHTER AMOUNTS THAT WAS EARLIER ANTICIPATED. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 AN ACTIVE DAY SHAPING UP AS LOW PRESSURE STACKS OVR CENTRAL NEBRASKA. SATELLITE PIX SHOWS THIS WELL-DEFINED LOW PRESSURE SPINNING ALONG THE CO/NM STATELINE WITH THE LAST FEW FRAMES BEGINNING TO SHOW A NORTHEASTERLY TURN. 08Z SFC ANALYSIS PLACES 986MB LOW JUST TO THE EAST OF THE CWFA...NORTHEAST OF OGALLALA. HAVE SEEN A BREAK PRECIP OVR THE PAST FEW HOURS WITH THE EXCEPTION OF UP TO AN INCH OF NEW SNOW FALLING OVR THE SRN LARAMIE RANGE. HOWEVER...THIS TOO LOOKS SHORT-LIVED AS SHOWERS HAVE BEGAN TO BLOSSOM OVR NRN COLORADO SINCE 0830Z. MODELS ARE ALL SIMILAR IN STACKING THIS STRONG AREA OF LOW PRESSURE ALONG THE NE/KS STATELINES BY 00Z MONDAY. THIS TRACK HAS TRENDED TOWARDS THE SRN SOLUTIONS FROM A FEW DAYS AGO. TWO MAIN CONCERNS FROM THIS STORM TODAY WILL BE THE STRONG WIND POTENTIAL MAINLY THIS AFTERNOON AS WELL AS SNOW ACCUMULATIONS AND SNOW LEVELS. THE SRN TRACK OF THE LOW HAS SHIFTED THE STRONGEST WINDS FARTHER SOUTH THAN EARLIER RUNS HAD SUGGESTED. SO...HAVE CANCELLED THE HIGH WIND WATCH ACROSS CONVERSE/NIOBRARA/GOSHEN/PLATTE COUNTIES. FARTHER SOUTH...THE GFS/NAM STILL HAVE DIFFERING SOLUTIONS WITH THE NAM SIGNIFICANTLY WEAKER THAN THE GFS. A RESULT OF THE NAM SHOWING VERY LITTLE MIXING IN THE BOUNDARY LAYER. COMPARATIVELY...THE GFS IS AS IT USUALLY IS...THE BULLISH OUTLIER WHEN IT COMES TO THE DEPTH OF THE MIXED LAYER AND AVAILABLE WIND SPEEDS AT THE TOP. MEANWHILE... LATEST HRRR OUTPUT SUGGEST GUSTS OF 45-55 MPH FROM CHEYENNE TO SIDNEY BY THIS AFTERNOON. MUCH WILL DEPEND ON HOW OF THE STEEP SUN ANGLE IS ABLE TO MIX THE BOUNDARY LAYER THIS AFTERNOON. HAVE OPTED TO UPGRADE TO A HIGH WIND WARNING FOR LARAMIE...KIMBALL AND CHEYENNE COUNTIES. HOWEVER...IT LOOKS TO BE A FAIRLY MARGINAL EVENT AT THIS POINT. HAVE ALSO ADDED SCOTTS BLUFF...BANNER AND MORRILL COUNTIES TO A WIND ADVISORY. PRECIP HAS BEEN FAIRLY SLOW TO GET GOING THIS MORNING...BUT THIS WILL CHANGE SHORTLY AS IMPRESSIVE POCKET OF QG LIFT MOVES FROM NORTHEAST COLORADO INTO WRN NEBRASKA. SO...EXPECT PRECIP TO BEGIN TO INCREASE THRU THE MORNING. WET BULB ZERO HEIGHTS HAVE ALREADY FALLEN TO AROUND 6500 FEET THIS MORNING AND WITH PRECIPITATION...THESE WILL LIKELY FALL TO AROUND 5500 FEET. SNOW AMOUNTS WILL LIKELY BE ON THE LIGHT SIDE OF WARNING CRITERIA...BUT GIVEN HOW LATE IN THE SEASON IT IS...PLUS THE COMBINATION OF THE STRONG NORTHWEST WINDS...FEEL THE WINTER STORM WARNING IS STILL JUSTIFIED FOR NOW. THIS MAY CHANGE DEPENDING UPON HOW SNOW DEVELOPS THIS MORNING. PRECIPITATION WILL LIFT INTO ERN ZONES FOR THIS EVENING AND TONIGHT. SNOW-LEVELS WILL FALL TO AROUND 4000 FEET TONIGHT...SO SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE EVEN ALONG THE PINE RIDGE. THE UPPER-LOW WILL WOBBLE AROUND IN NEBRASKA ON MONDAY MOVING VERY LITTLE. PRECIPITATION COVERAGE WILL BE LESS ON MONDAY...WHICH WILL ALLOW FOR DEEPER BOUNDARY LAYER MIXING. WILL UNDOUBTEDLY BE STARING AT ANOTHER DAY OF POTENTIAL WIND HIGHLIGHTS...ESPECIALLY OVR PORTIONS OF THE WRN NEBRASKA PANHANDLE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 UNSEASONABLY COOL PATTERN IS STILL SHOWN THROUGH MUCH OF THE EXTENDED PERIOD. NORTHERLY FLOW ALOFT IS OVER THE REGION ON MON NIGHT AND CONTINUES WELL INTO THURS. THIS KEEPS 700MB TEMPS IN THE -6C TO -10C RANGE THROUGH THURS SO HIGHS WILL STRUGGLE TO GET OUT OF THE 40S...ESPECIALLY WITH WIDESPREAD CLOUD COVER. SHORTWAVES PIVOTING SOUTHWARD WILL COMBINE WITH GOOD 700-500MB MOISTURE TO KEEP A CHANCE OF LIGHT SHOWERS GOING MON NIGHT THROUGH WED. NOT EXPECTING ANY TSTMS IN THE STABLE COOL AIRMASS. THE OTHER MAIN STORY THROUGH WED WILL BE THE WINDY CONDITIONS ACROSS THE PLAINS. THE GFS INDICATES NORTHERLY 700MB WINDS OF 35-45 KTS FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE FOR THE ENTIRE PERIOD FROM MON NIGHT INTO THURS MORNING. OF COURSE WINDS WILL COME DOWN DURING THE OVERNIGHT HOURS WITH THE LOSS OF DAYTIME MIXING...HOWEVER MAY GET GUSTS TO ADVISORY CRITERIA OVER THE PANHANDLE AT LEAST ON TUES AFTN. THE GRADIENT WEAKENS BY THURS AND INTO FRI. WILL LIKELY BEGIN TO SEE TEMPS MODERATE ON FRI AND ESPECIALLY INTO SAT AS THE PERSISTENT NORTHERLY FLOW BECOMES MORE ZONAL. NOT SEEING ANY ABOVE AVERAGE TEMPS ANYTIME IN THE LONG TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 548 AM MDT SUN APR 27 2014 RADAR SHOWS THE COVERAGE OF RAIN AND SNOW BEGINNING TO INCREASE ACROSS AREAS IN SOUTHEAST WY. KEPT KLAR IN IFR VIS AND LIGHT SNOW THROUGH MID-MORNING. STILL SOME QUESTION AS TO WHETHER RAIN WILL TRANSITION OVER TO SNOW AT KCYS BY LATER THIS MORNING. A LARGE BAND OF LIGHT RAIN IS FCSTED TO DEVELOP OVER MUCH OF THE PANHANDLE BY LATE MORNING AND PERSIST THROUGH THE EVENING. GENERALLY HAVE MVFR CONDITIONS IN THE RAIN OVER THE PANHANDLE...ALTHOUGH BRIEF IFR VIS COULD BE POSSIBLE IF MODERATE RAIN DEVELOPS. NORTHWEST WINDS WILL INCREASE THROUGH THE MORNING WITH WIDESPREAD GUSTS TO 35-45 KTS EXPECTED IN THE AFTERNOON. && .FIRE WEATHER... ISSUED AT 339 AM MDT SUN APR 27 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A LARGE STORM SYSTEM WILL BE STATIONARY OVER THE CENTRAL PLAINS. UNSEASONABLY COOL TEMPERATURES COMBINED WITH WETTING RAINS/SNOWS WILL PREVENT ANY FIRE SPREAD CONCERNS. NORTHWEST WINDS OF 30 TO 50 MPH CAN BE EXPECTED OVER A LARGE PART OF THE DISTRICT HOWEVER DURING THIS PERIOD. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR WYZ118-119. WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ103- 105-110-112-114>117. NE...HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR NEZ054-055. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ019>021. && $$ UPDATE...HAHN SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
553 AM MDT SUN APR 27 2014 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 AN ACTIVE DAY SHAPING UP AS LOW PRESSURE STACKS OVR CENTRAL NEBRASKA. SATELLITE PIX SHOWS THIS WELL-DEFINED LOW PRESSURE SPINNING ALONG THE CO/NM STATELINE WITH THE LAST FEW FRAMES BEGINNING TO SHOW A NORTHEASTERLY TURN. 08Z SFC ANALYSIS PLACES 986MB LOW JUST TO THE EAST OF THE CWFA...NORTHEAST OF OGALLALA. HAVE SEEN A BREAK PRECIP OVR THE PAST FEW HOURS WITH THE EXCEPTION OF UP TO AN INCH OF NEW SNOW FALLING OVR THE SRN LARAMIE RANGE. HOWEVER...THIS TOO LOOKS SHORT-LIVED AS SHOWERS HAVE BEGAN TO BLOSSOM OVR NRN COLORADO SINCE 0830Z. MODELS ARE ALL SIMILAR IN STACKING THIS STRONG AREA OF LOW PRESSURE ALONG THE NE/KS STATELINES BY 00Z MONDAY. THIS TRACK HAS TRENDED TOWARDS THE SRN SOLUTIONS FROM A FEW DAYS AGO. TWO MAIN CONCERNS FROM THIS STORM TODAY WILL BE THE STRONG WIND POTENTIAL MAINLY THIS AFTERNOON AS WELL AS SNOW ACCUMULATIONS AND SNOW LEVELS. THE SRN TRACK OF THE LOW HAS SHIFTED THE STRONGEST WINDS FARTHER SOUTH THAN EARLIER RUNS HAD SUGGESTED. SO...HAVE CANCELLED THE HIGH WIND WATCH ACROSS CONVERSE/NIOBRARA/GOSHEN/PLATTE COUNTIES. FARTHER SOUTH...THE GFS/NAM STILL HAVE DIFFERING SOLUTIONS WITH THE NAM SIGNIFICANTLY WEAKER THAN THE GFS. A RESULT OF THE NAM SHOWING VERY LITTLE MIXING IN THE BOUNDARY LAYER. COMPARATIVELY...THE GFS IS AS IT USUALLY IS...THE BULLISH OUTLIER WHEN IT COMES TO THE DEPTH OF THE MIXED LAYER AND AVAILABLE WIND SPEEDS AT THE TOP. MEANWHILE... LATEST HRRR OUTPUT SUGGEST GUSTS OF 45-55 MPH FROM CHEYENNE TO SIDNEY BY THIS AFTERNOON. MUCH WILL DEPEND ON HOW OF THE STEEP SUN ANGLE IS ABLE TO MIX THE BOUNDARY LAYER THIS AFTERNOON. HAVE OPTED TO UPGRADE TO A HIGH WIND WARNING FOR LARAMIE...KIMBALL AND CHEYENNE COUNTIES. HOWEVER...IT LOOKS TO BE A FAIRLY MARGINAL EVENT AT THIS POINT. HAVE ALSO ADDED SCOTTS BLUFF...BANNER AND MORRILL COUNTIES TO A WIND ADVISORY. PRECIP HAS BEEN FAIRLY SLOW TO GET GOING THIS MORNING...BUT THIS WILL CHANGE SHORTLY AS IMPRESSIVE POCKET OF QG LIFT MOVES FROM NORTHEAST COLORADO INTO WRN NEBRASKA. SO...EXPECT PRECIP TO BEGIN TO INCREASE THRU THE MORNING. WET BULB ZERO HEIGHTS HAVE ALREADY FALLEN TO AROUND 6500 FEET THIS MORNING AND WITH PRECIPITATION...THESE WILL LIKELY FALL TO AROUND 5500 FEET. SNOW AMOUNTS WILL LIKELY BE ON THE LIGHT SIDE OF WARNING CRITERIA...BUT GIVEN HOW LATE IN THE SEASON IT IS...PLUS THE COMBINATION OF THE STRONG NORTHWEST WINDS...FEEL THE WINTER STORM WARNING IS STILL JUSTIFIED FOR NOW. THIS MAY CHANGE DEPENDING UPON HOW SNOW DEVELOPS THIS MORNING. PRECIPITATION WILL LIFT INTO ERN ZONES FOR THIS EVENING AND TONIGHT. SNOW-LEVELS WILL FALL TO AROUND 4000 FEET TONIGHT...SO SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE EVEN ALONG THE PINE RIDGE. THE UPPER-LOW WILL WOBBLE AROUND IN NEBRASKA ON MONDAY MOVING VERY LITTLE. PRECIPITATION COVERAGE WILL BE LESS ON MONDAY...WHICH WILL ALLOW FOR DEEPER BOUNDARY LAYER MIXING. WILL UNDOUBTEDLY BE STARING AT ANOTHER DAY OF POTENTIAL WIND HIGHLIGHTS...ESPECIALLY OVR PORTIONS OF THE WRN NEBRASKA PANHANDLE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 UNSEASONABLY COOL PATTERN IS STILL SHOWN THROUGH MUCH OF THE EXTENDED PERIOD. NORTHERLY FLOW ALOFT IS OVER THE REGION ON MON NIGHT AND CONTINUES WELL INTO THURS. THIS KEEPS 700MB TEMPS IN THE -6C TO -10C RANGE THROUGH THURS SO HIGHS WILL STRUGGLE TO GET OUT OF THE 40S...ESPECIALLY WITH WIDESPREAD CLOUD COVER. SHORTWAVES PIVOTING SOUTHWARD WILL COMBINE WITH GOOD 700-500MB MOISTURE TO KEEP A CHANCE OF LIGHT SHOWERS GOING MON NIGHT THROUGH WED. NOT EXPECTING ANY TSTMS IN THE STABLE COOL AIRMASS. THE OTHER MAIN STORY THROUGH WED WILL BE THE WINDY CONDITIONS ACROSS THE PLAINS. THE GFS INDICATES NORTHERLY 700MB WINDS OF 35-45 KTS FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE FOR THE ENTIRE PERIOD FROM MON NIGHT INTO THURS MORNING. OF COURSE WINDS WILL COME DOWN DURING THE OVERNIGHT HOURS WITH THE LOSS OF DAYTIME MIXING...HOWEVER MAY GET GUSTS TO ADVISORY CRITERIA OVER THE PANHANDLE AT LEAST ON TUES AFTN. THE GRADIENT WEAKENS BY THURS AND INTO FRI. WILL LIKELY BEGIN TO SEE TEMPS MODERATE ON FRI AND ESPECIALLY INTO SAT AS THE PERSISTENT NORTHERLY FLOW BECOMES MORE ZONAL. NOT SEEING ANY ABOVE AVERAGE TEMPS ANYTIME IN THE LONG TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 548 AM MDT SUN APR 27 2014 RADAR SHOWS THE COVERAGE OF RAIN AND SNOW BEGINNING TO INCREASE ACROSS AREAS IN SOUTHEAST WY. KEPT KLAR IN IFR VIS AND LIGHT SNOW THROUGH MID-MORNING. STILL SOME QUESTION AS TO WHETHER RAIN WILL TRANSITION OVER TO SNOW AT KCYS BY LATER THIS MORNING. A LARGE BAND OF LIGHT RAIN IS FCSTED TO DEVELOP OVER MUCH OF THE PANHANDLE BY LATE MORNING AND PERSIST THROUGH THE EVENING. GENERALLY HAVE MVFR CONDITIONS IN THE RAIN OVER THE PANHANDLE...ALTHOUGH BRIEF IFR VIS COULD BE POSSIBLE IF MODERATE RAIN DEVELOPS. NORTHWEST WINDS WILL INCREASE THROUGH THE MORNING WITH WIDESPREAD GUSTS TO 35-45 KTS EXPECTED IN THE AFTERNOON. && .FIRE WEATHER... ISSUED AT 339 AM MDT SUN APR 27 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A LARGE STORM SYSTEM WILL BE STATIONARY OVER THE CENTRAL PLAINS. UNSEASONABLY COOL TEMPERATURES COMBINED WITH WETTING RAINS/SNOWS WILL PREVENT ANY FIRE SPREAD CONCERNS. NORTHWEST WINDS OF 30 TO 50 MPH CAN BE EXPECTED OVER A LARGE PART OF THE DISTRICT HOWEVER DURING THIS PERIOD. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING FROM 9 AM THIS MORNING TO 9 PM MDT THIS EVENING FOR WYZ118-119. WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ103- 105-110-112-114>117. NE...HIGH WIND WARNING FROM 9 AM THIS MORNING TO 9 PM MDT THIS EVENING FOR NEZ054-055. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ019>021. && $$ SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
402 AM MDT SUN APR 27 2014 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 AN ACTIVE DAY SHAPING UP AS LOW PRESSURE STACKS OVR CENTRAL NEBRASKA. SATELLITE PIX SHOWS THIS WELL-DEFINED LOW PRESSURE SPINNING ALONG THE CO/NM STATELINE WITH THE LAST FEW FRAMES BEGINNING TO SHOW A NORTHEASTERLY TURN. 08Z SFC ANALYSIS PLACES 986MB LOW JUST TO THE EAST OF THE CWFA...NORTHEAST OF OGALLALA. HAVE SEEN A BREAK PRECIP OVR THE PAST FEW HOURS WITH THE EXCEPTION OF UP TO AN INCH OF NEW SNOW FALLING OVR THE SRN LARAMIE RANGE. HOWEVER...THIS TOO LOOKS SHORT-LIVED AS SHOWERS HAVE BEGAN TO BLOSSOM OVR NRN COLORADO SINCE 0830Z. MODELS ARE ALL SIMILAR IN STACKING THIS STRONG AREA OF LOW PRESSURE ALONG THE NE/KS STATELINES BY 00Z MONDAY. THIS TRACK HAS TRENDED TOWARDS THE SRN SOLUTIONS FROM A FEW DAYS AGO. TWO MAIN CONCERNS FROM THIS STORM TODAY WILL BE THE STRONG WIND POTENTIAL MAINLY THIS AFTERNOON AS WELL AS SNOW ACCUMULATIONS AND SNOW LEVELS. THE SRN TRACK OF THE LOW HAS SHIFTED THE STRONGEST WINDS FARTHER SOUTH THAN EARLIER RUNS HAD SUGGESTED. SO...HAVE CANCELLED THE HIGH WIND WATCH ACROSS CONVERSE/NIOBRARA/GOSHEN/PLATTE COUNTIES. FARTHER SOUTH...THE GFS/NAM STILL HAVE DIFFERING SOLUTIONS WITH THE NAM SIGNIFICANTLY WEAKER THAN THE GFS. A RESULT OF THE NAM SHOWING VERY LITTLE MIXING IN THE BOUNDARY LAYER. COMPARATIVELY...THE GFS IS AS IT USUALLY IS...THE BULLISH OUTLIER WHEN IT COMES TO THE DEPTH OF THE MIXED LAYER AND AVAILABLE WIND SPEEDS AT THE TOP. MEANWHILE... LATEST HRRR OUTPUT SUGGEST GUSTS OF 45-55 MPH FROM CHEYENNE TO SIDNEY BY THIS AFTERNOON. MUCH WILL DEPEND ON HOW OF THE STEEP SUN ANGLE IS ABLE TO MIX THE BOUNDARY LAYER THIS AFTERNOON. HAVE OPTED TO UPGRADE TO A HIGH WIND WARNING FOR LARAMIE...KIMBALL AND CHEYENNE COUNTIES. HOWEVER...IT LOOKS TO BE A FAIRLY MARGINAL EVENT AT THIS POINT. HAVE ALSO ADDED SCOTTS BLUFF...BANNER AND MORRILL COUNTIES TO A WIND ADVISORY. PRECIP HAS BEEN FAIRLY SLOW TO GET GOING THIS MORNING...BUT THIS WILL CHANGE SHORTLY AS IMPRESSIVE POCKET OF QG LIFT MOVES FROM NORTHEAST COLORADO INTO WRN NEBRASKA. SO...EXPECT PRECIP TO BEGIN TO INCREASE THRU THE MORNING. WET BULB ZERO HEIGHTS HAVE ALREADY FALLEN TO AROUND 6500 FEET THIS MORNING AND WITH PRECIPITATION...THESE WILL LIKELY FALL TO AROUND 5500 FEET. SNOW AMOUNTS WILL LIKELY BE ON THE LIGHT SIDE OF WARNING CRITERIA...BUT GIVEN HOW LATE IN THE SEASON IT IS...PLUS THE COMBINATION OF THE STRONG NORTHWEST WINDS...FEEL THE WINTER STORM WARNING IS STILL JUSTIFIED FOR NOW. THIS MAY CHANGE DEPENDING UPON HOW SNOW DEVELOPS THIS MORNING. PRECIPITATION WILL LIFT INTO ERN ZONES FOR THIS EVENING AND TONIGHT. SNOW-LEVELS WILL FALL TO AROUND 4000 FEET TONIGHT...SO SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE EVEN ALONG THE PINE RIDGE. THE UPPER-LOW WILL WOBBLE AROUND IN NEBRASKA ON MONDAY MOVING VERY LITTLE. PRECIPITATION COVERAGE WILL BE LESS ON MONDAY...WHICH WILL ALLOW FOR DEEPER BOUNDARY LAYER MIXING. WILL UNDOUBTEDLY BE STARING AT ANOTHER DAY OF POTENTIAL WIND HIGHLIGHTS...ESPECIALLY OVR PORTIONS OF THE WRN NEBRASKA PANHANDLE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 339 AM MDT SUN APR 27 2014 UNSEASONABLY COOL PATTERN IS STILL SHOWN THROUGH MUCH OF THE EXTENDED PERIOD. NORTHERLY FLOW ALOFT IS OVER THE REGION ON MON NIGHT AND CONTINUES WELL INTO THURS. THIS KEEPS 700MB TEMPS IN THE -6C TO -10C RANGE THROUGH THURS SO HIGHS WILL STRUGGLE TO GET OUT OF THE 40S...ESPECIALLY WITH WIDESPREAD CLOUD COVER. SHORTWAVES PIVOTING SOUTHWARD WILL COMBINE WITH GOOD 700-500MB MOISTURE TO KEEP A CHANCE OF LIGHT SHOWERS GOING MON NIGHT THROUGH WED. NOT EXPECTING ANY TSTMS IN THE STABLE COOL AIRMASS. THE OTHER MAIN STORY THROUGH WED WILL BE THE WINDY CONDITIONS ACROSS THE PLAINS. THE GFS INDICATES NORTHERLY 700MB WINDS OF 35-45 KTS FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE FOR THE ENTIRE PERIOD FROM MON NIGHT INTO THURS MORNING. OF COURSE WINDS WILL COME DOWN DURING THE OVERNIGHT HOURS WITH THE LOSS OF DAYTIME MIXING...HOWEVER MAY GET GUSTS TO ADVISORY CRITERIA OVER THE PANHANDLE AT LEAST ON TUES AFTN. THE GRADIENT WEAKENS BY THURS AND INTO FRI. WILL LIKELY BEGIN TO SEE TEMPS MODERATE ON FRI AND ESPECIALLY INTO SAT AS THE PERSISTENT NORTHERLY FLOW BECOMES MORE ZONAL. NOT SEEING ANY ABOVE AVERAGE TEMPS ANYTIME IN THE LONG TERM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 1148 PM MDT SAT APR 26 2014 SCATTERED SHOWERS WILL BE POSSIBLE OVER MUCH OF THE AREA THROUGH THE NIGHT. KLAR COULD CHANGE OVER TO SNOW AFTER AROUND 09Z...SO HAVE IFR VIS IN LIGHT SNOW AT THAT POINT. MVFR CIGS WILL BE POSSIBLE AT KCDR THROUGH THE NIGHT. NORTHWEST WINDS WILL ALSO BEGIN TO INCREASE AFTER AROUND 09Z...ESPECIALLY OVER SOUTHEAST WY WHERE GUSTS TO 35 KTS WILL BE POSSIBLE. && .FIRE WEATHER... ISSUED AT 339 AM MDT SUN APR 27 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A LARGE STORM SYSTEM WILL BE STATIONARY OVER THE CENTRAL PLAINS. UNSEASONABLY COOL TEMPERATURES COMBINED WITH WETTING RAINS/SNOWS WILL PREVENT ANY FIRE SPREAD CONCERNS. NORTHWEST WINDS OF 30 TO 50 MPH CAN BE EXPECTED OVER A LARGE PART OF THE DISTRICT HOWEVER DURING THIS PERIOD. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING FROM 9 AM THIS MORNING TO 9 PM MDT THIS EVENING FOR WYZ118-119. WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR WYZ103-105- 110-112-114>117. NE...HIGH WIND WARNING FROM 9 AM THIS MORNING TO 9 PM MDT THIS EVENING FOR NEZ054-055. WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR NEZ019>021. && $$ SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS ALBANY NY
501 AM EDT TUE APR 29 2014 .SYNOPSIS... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. TEMPERATURES WILL REMAIN QUITE COOL THROUGH WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 445 AM EDT...LOW CLOUDS HAVE OVERSPREAD MOST OF THE REGION...WITH THE EXCEPTION OF PORTIONS OF THE WESTERN ADIRONDACKS AND MOHAWK VALLEY. THE COMBINATION OF CLOUDS...AND SOME WIND...HAVE KEPT TEMPS FROM FALLING MUCH OVERNIGHT...AND ARE GENERALLY STILL IN THE MID 40S TO LOWER 50S. TEMPS MAY FALL ANOTHER 2-4 DEGREES THROUGH SUNRISE...ESP ACROSS PORTIONS OF THE BERKSHIRES AND SOUTHERN VT...AS SLIGHTLY COOLER AIR SPREADS WESTWARD...ALONG WITH SOME ADIABATIC COOLING FROM LIFTING ACROSS EAST FACING TERRAIN. THROUGH THIS MORNING...EXPECT MOSTLY CLOUDY SKIES TO CONTINUE...ALTHOUGH A FEW BREAKS IN THE CLOUDS ARE POSSIBLE...ESP ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE A DOWNSLOPING E/SE FLOW MAY HELP TO OCCASIONALLY BREAK UP THE LOWER CLOUD DECK. OTHERWISE...LITTLE IN THE WAY OF RAINFALL IS EXPECTED THROUGH NOONTIME...WITH THE POSSIBLE EXCEPTION BEING SOME SPOTTY DRIZZLE OR SPRINKLES ACROSS UPSLOPE AREAS OF THE SOUTHERN GREEN MTNS/BERKSHIRES...AND PERHAPS THE EASTERN CATSKILLS. TEMPS SHOULD SLOWLY RISE INTO AND THROUGH THE LOWER/MID 50S IN MOST AREAS...AND PERHAPS UPPER 50S ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE SOME BRIEF BREAKS OF SUN AND WARMING FROM DOWNSLOPING IS POSSIBLE. THIS AFTERNOON...LIGHT RAIN SHOULD BEGIN TO OVERSPREAD THE REGION FROM WEST/SOUTHWEST TO EAST/NORTHEAST. HAVE FOLLOWED THE RUC 13/HRRR AND HI-RES WRF FOR GENERAL TIMING...WHICH BRINGS RAIN INTO THE WESTERN MOHAWK VALLEY/SCHOHARIE VALLEY/EASTERN CATSKILLS AND MID HUDSON VALLEY MAINLY W OF THE HUDSON RIVER BETWEEN 1-3 PM...INTO THE CENTRAL/EASTERN MOHAWK VALLEY...CAPITAL REGION...MID HUDSON VALLEY E OF THE HUDSON RIVER AND WESTERN LITCHFIELD CO BETWEEN ROUGHLY 2 AND 4 PM...ACROSS THE LAKE GEORGE REGION/SE ADIRONDACKS/UPPER HUDSON VALLEY AND EASTERN LITCHFIELD CO BETWEEN 4-6 PM...AND EVENTUALLY INTO SOUTHERN VT AND THE BERKSHIRES BETWEEN 6-8 PM. TEMPS WILL LIKELY FALL SEVERAL DEGREES ONCE THE RAIN BEGINS DUE TO WET BULB/EVAPORATIONAL COOLING. EAST/SOUTHEAST WINDS WILL INCREASE THROUGH THE DAY...WITH SOME GUSTS POSSIBLY REACHING 20-25 MPH AT TIMES...EXCEPT 25-35 MPH ACROSS PORTIONS OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... TONIGHT...A SURGE OF ISENTROPIC LIFT...MOST NOTABLY ALONG THE 300 K SFC...WILL DEVELOP FROM W TO E ACROSS THE REGION OVERNIGHT. EXPECT PERIODS OF LIGHT TO MODERATE RAIN OVERNIGHT...WITH THE STEADIEST AND MOST PERSISTENT RAIN EXPECTED ACROSS PORTIONS OF THE WESTERN MOHAWK VALLEY AND SW ADIRONDACKS...AS WELL AS ACROSS THE EASTERN CATSKILLS. SOME SLEET COULD MIX IN AT TIMES ACROSS HIGHER ELEVATIONS OF THE SW ADIRONDACKS...SOUTHERN VT AND NORTHERN BERKSHIRES...AND PERHAPS EVEN THE EASTERN CATSKILLS AS A DRY WEDGE AROUND 3500-5000 FT AGL ADVECTS WESTWARD...WHILE RAIN FALLS THROUGH THIS LAYER. GUSTY E/SE WINDS WILL CONTINUE...OCCASIONALLY GUSTING UP TO 25-35 MPH AT TIMES ACROSS THE HIGHER TERRAIN OF WESTERN NEW ENGLAND AND THE TACONICS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. WED-THU MORNING...THE COMBINATION OF ISENTROPIC LIFT...LOW LEVEL CONVERGENCE...AND OVERALL SYNOPTIC FORCING...AS WELL AS THE CLOSEST PROXIMITY OF THE LOW LEVEL JET...WILL MOVE ACROSS THE REGION LATE WED INTO WED NT...RESULTING IN THE PERIOD OF HEAVIEST RAINFALL. THE RAIN MAY BE MORE INTERMITTENT AT TIMES WED AM...BEFORE SEVERAL SURGES OF MODERATE TO EVEN HEAVY RAIN DEVELOP LATE WED AFTN INTO WED NT. IN ADDITION...SHOWALTER INDICES ARE FORECAST TO DIP INTO THE 0 TO -2 C RANGE WED NT FROM AROUND INTERSTATE 90 SOUTHWARD. HAVE THEREFORE INCLUDED SLIGHT CHC OF THUNDER FOR CENTRAL AND SOUTHERN AREAS. BY EARLY THU...THE BEST AXIS OF FORCING AND ELEVATED INSTABILITY SHOULD SHIFT PRIMARILY INTO THE MID HUDSON VALLEY...NW CT...AND PERHAPS SW MA...WHERE THE HEAVIEST RAINFALL SHOULD STILL BE OCCURRING. GIVEN THAT THE SOUTH TO SOUTHWEST FLOW THROUGH A DEEP LAYER OF THE MIDDLE/UPPER TROPOSPHERE WILL LINE UP...THERE IS SOME POTENTIAL FOR TRAINING OF HEAVIER RAINFALL. HOWEVER...THERE REMAINS SOME UNCERTAINTY AS TO WHERE ANY POTENTIAL AXIS OF HEAVIEST AND MOST PERSISTENT RAINFALL WILL OCCUR...AS SOME MODELS SUGGEST THIS AXIS COULD SET UP JUST SOUTH AND WEST OF OUR REGION. IN ADDITION...THERE IS SOME POSSIBILITY THAT DEEPER CONVECTION CLOSE TO THE DEVELOPING TRIPLE POINT ACROSS NJ OR NYC/LI COULD LIMIT THE OVERALL MOISTURE TRANSPORT FURTHER N INTO OUR REGION. DUE TO THIS LINGERING UNCERTAINTY...WILL HOLD OFF ON ANY FLOOD WATCH AT THIS TIME. AS FOR TEMPS...WED SHOULD BE QUITE COOL GIVEN CLOUDS AND RAINFALL...WITH MAXES GENERALLY ONLY REACHING THE MID 40S TO LOWER 50S. TEMPS WILL HOLD NEARLY STEADY OR FALL SLIGHTLY FROM THESE MAX TEMPS EARLY WED NT...BEFORE GRADUALLY RISING AGAIN LATE WED NT. ALSO...WILL HAVE TO WATCH FOR STRONG WIND POTENTIAL WED AFTERNOON AND NIGHT...ESP ACROSS THE HIGHER TERRAIN OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AND PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS...WHERE SOME EAST/SOUTHEAST WINDS COULD GUST OVER 45 MPH. IF THIS POTENTIAL INCREASES FURTHER...THEN WIND ADVISORIES MAY NEED TO BE ISSUED FOR THESE AREAS. THU AFTN-THU NT...AN OCCLUDED FRONTAL BOUNDARY SHOULD MOVE EAST OF THE REGION BY THU AFTN. HOWEVER...SOME SHOWERS WILL REMAIN POSSIBLE AS THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. SHOWERS SHOULD GRADUALLY DECREASE IN AREAL COVERAGE THU NT. TEMPS ON THU SHOULD REACH 65-70 IN VALLEYS...AND MID 50S TO MID 60S FOR HIGHER ELEVATIONS...WITH EVEN WARMER MAX TEMPS POSSIBLE IF SOME BREAKS OF SUN DEVELOP IN THE AFTERNOON. EXPECT THU NT MINS TO FALL INTO THE MID 30S TO LOWER 40S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AN UNSETTLED PATTERN WILL CONTINUE THROUGH MUCH OF THE LONG TERM PERIOD. FOR FRIDAY...EXPECT WIDELY SCATTERED TO SCATTERED SHOWERS WITH THE HIGHEST POPS ACRS THE NORTHWEST THIRD OF THE FA. THIS WILL BE DUE TO THE MID LEVEL TROUGH AXIS PASSING ACROSS THE FA WITH SEVERAL VORT MAXS ROTATING AROUND THE BASE OF THE TROUGH. HIGHS ON FRIDAY ARE EXPECTED TO BE IN THE UPPER 40S AND LOWER 50S TO MID 60S ACRS THE SE PTN OF THE FA. BY FRIDAY NIGHT. THE BEST CHANCE OF SEEING SHOWERS WILL BE ACRS THE WRN ADIRONDACKS WHERE SOME LAKE ENHANCED SHOWERS ARE POSSIBLE. LOWS FRIDAY NIGHT WILL RANGE FROM THE MID 30S NORTHWEST TO MID 40S SOUTHEAST. SO LIGHT SNOW ACCUMULATION IS POSSIBLE ACROSS THE WESTERN ADIRONDACKS. ON SATURDAY AND SATURDAY NIGHT...THERE WILL BE ANOTHER SHORTWAVE TROUGH AXIS IN CLOSE PROXIMITY TO OUR REGION. HAVE GONE WITH LIKELY POPS SATURDAY ACRS THE NORTHWEST THIRD OF THE FA WITH CHANCE POPS ELSEWHERE AND CHANCE POPS ACRS THE FA SATURDAY NIGHT. HIGHS WILL RANGE FROM THE MID 50S TO MID 60S WITH LOWS SATURDAY NIGHT IN THE MID 30S TO MID 40S ONCE AGAIN.. SUNDAY INTO MONDAY...A STRONG CLOSED OFF UPPER LEVEL LOW WILL APPROACH THE REGION...AS IT ROTATES AROUND THE BROAD SCALE UPPER LEVEL TROUGH SITUATED OVER EASTERN CANADA. THIS WILL PROVIDE LIFT FOR SOME ADDITIONAL RAIN SHOWERS ALTHOUGH THEIR WILL BE A GRADUAL DECREASE IN POPS AS WE GO FROM SUNDAY INTO MONDAY. EXPECT HIGHS ON SUNDAY AND MONDAY TO RANGE FROM THE MID 50S NORTHWEST TO THE MID 60S SOUTHEAST WITH LOWS SUNDAY NIGHT IN THE MID 30S TO MID 40S. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... A SPRAWLING STORM SYSTEM OVER THE GREAT PLAINS WILL SLOWLY APPROACH THE REGION OVER THE NEXT FEW DAYS. CLOUDS AT ALL LEVELS WILL INCREASE OVERNIGHT...ALTHOUGH IT WILL STAY DRY WITH NO PRECIPITATION AND REMAIN VFR...EXCEPT FOR SOME MVFR CONDITIONS AT KPSF...MOST SITES WILL HAVE BKN CIGS AT 5-7 KFT AND BKN-OVC CIGS AT 25K BY DAYBREAK TUESDAY. RAIN SHOWERS WILL SLOWLY SPREAD FROM SOUTHWEST TO NORTHEAST ACROSS THE REGION DURING THE AFTN HOURS. IT MAY TAKE UNTIL THE LATE AFTN OR EVENING FOR SHOWERS TO REACH KALB/KGFL...AND CONDITIONS SHOULD STAY VFR FOR THESE SITES. FURTHER SOUTH...KPOU/KPSF MAY SEE MVFR CIGS/VSBYS BY LATE IN THE DAY...AS COVERAGE AND INTENSITY OF SHOWERS INCREASE. MOST TAF SITES CAN EXPECT MVFR CONDITIONS WITH REDUCED VISIBILITY BY LATE EVENING WITH SHOWERS...EXCEPT FOR KPSF WHICH WILL HAVE IFR CONDITIONS WITH AN INCREASING PRESSURE GRADIENT...E-SE WINDS OF 5-10 KTS TONIGHT WILL INCREASE TO AROUND 10-15 KTS ON TUESDAY...AND BE STRONGEST DURING THE AFTN/EVENING HOURS. OUTLOOK... WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. PDS RA...TSRA. THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... ...WIND GUSTS OF 25-35 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON...ESPECIALLY ACROSS HIGHER ELEVATIONS OF WESTERN NEW ENGLAND... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. MINIMUMS RELATIVE HUMIDITIES WILL FALL INTO THE 30-40 PERCENT RANGE THIS AFTERNOON ACROSS THE UPPER HUDSON VALLEY AND SOUTHERN VT...AND 40-50 PERCENT ELSEWHERE. THE RH WILL RECOVER TO 75-90 PERCENT TONIGHT...WITH A WETTING RAINFALL DEVELOPING. THE RH WILL FALL INTO THE 60-70 PERCENT RANGE WED AFTERNOON. EAST TO SOUTHEAST WINDS WILL INCREASE TO 15-25 MPH TODAY...WITH SOME GUSTS UP TO 35 MPH POSSIBLE ACROSS HIGHER ELEVATIONS. THESE WINDS WILL DECREASE SLIGHTLY TONIGHT TO 10-20 MPH...THEN INCREASE ONCE AGAIN BY WED AFTERNOON TO 15-30 MPH. && .HYDROLOGY... ...THE POTENTIAL FOR HEAVY RAINFALL CONTINUES TO INCREASE...ESPECIALLY FOR THE SE CATSKILLS...MID HUDSON VALLEY AND INTO NW CT... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BRING AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER.THE RAIN COULD COME DOWN HEAVY AT TIMES LATE WEDNESDAY AFTERNOON THROUGH EARLY THURSDAY MORNING...RESULTING IN THE BULK OF THE RAINFALL. AT THIS TIME...EXPECTED RAINFALL FOR TUESDAY THROUGH THURSDAY IS 1 TO 2 INCHES...WITH 2 TO 3 INCHES ACROSS THE CENTRAL AND SOUTHEASTERN CATSKILLS...MID HUDSON VALLEY INTO THE BERKSHIRES AND ACROSS LITCHFIELD COUNTY. THIS RAINFALL WOULD RESULT IN WIDESPREAD SIGNIFICANT WITHIN BACK RISES ON RIVERS AND STREAMS...AND MINOR FLOODING OF URBAN...LOW LYING AND POOR DRAINAGE AREAS DURING PERIOD OF HEAVY RAINFALL. BASED ON CURRENT FORECASTS...SOME OF THE RIVER POINTS IN THE HOUSATONIC BASIN WOULD REACH ACTION STAGE WITH CLOSE TO MINOR FLOOD POSSIBLE IN THE LOWER PORTION OF THE BASIN AT GAYLORDSVILLE AND STEVENSON DAM. THERE IS STILL UNCERTAINTY IN THE FORECAST SINCE WE ARE DEALING WITH A CUT OFF LOW PRESSURE SYSTEM. SMALL CHANGES IN THE FORECASTED RAINFALL COULD LEAD TO FLOODING ISSUES. AS OF NOW...THE HEAVIEST AXIS OF MOST PERSISTENT RAINFALL LOOKS TO BE JUST SOUTHWEST OF OUR REGION. HOWEVER...SHOULD FUTURE FORECASTS SUGGEST THAT THIS AXIS SHIFTS FURTHER NORTH AND EAST...THEN A FLOOD WATCH MAY HAVE TO BE ISSUED FOR PORTIONS OF THE FORECAST AREA. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...KL/IAA/FRUGIS NEAR TERM...KL SHORT TERM...KL LONG TERM...FRUGIS/11 AVIATION...FRUGIS/11 FIRE WEATHER...KL/IAA HYDROLOGY...KL/IAA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
416 AM CDT TUE APR 29 2014 .DISCUSSION... 309 AM CDT MASSIVE UPPER LOW THAT HAS DOMINATED THE WEATHER THE PAST COUPLE DAYS WILL CONTINUE TO DO SO FOR SEVERAL MORE DAYS AS A VERY IMPRESSIVE REX BLOCK AS SET UP WITH A NEARLY 580DM UPPER HIGH OVER HUDSON BAY. MODELS DO WEAKEN THE UPPER HIGH OVER THE NEXT COUPLE DAYS WHICH ALLOWS UPPER LOW TO WOBBLE NORTHWARD WHILE SLOWLY FILLING AND ITS IMPACTS ON THE REGION GRADUALLY LESSENING. SURFACE LOW OVER SOUTHWEST IOWA EARLY THIS MORNING WILL MOVE EAST-NORTHEASTWARD TODAY INTO NORTHERN ILLINOIS BY THIS EVENING. BAROCLINICITY OF THE SYSTEM CONTINUES TO WEAKEN BUT REMNANT WARM FRONT EXTENDING EAST FROM THE LOW WILL LIFT NORTH ACROSS THE CWA TODAY AND RESULT IN A WIND SHIFT TO THE SOUTH ACROSS MOST...IF NOT ALL...OF THE CWA THIS AFTERNOON. IN ADDITION TO WHAT IS LEFT OF THE WARM FRONT LIFTING NORTH...WE SHOULD ALSO SEE A PRONOUNCE MID LEVEL DRY INTRUSION ROTATE NORTHWARD INTO THE CWA THIS MORNING AND RESULT IN A PERIOD OF SUNSHINE THIS MORNING...POSSIBLY INTO THE AFTERNOON. CONCERNED THAT THIS MIXED SUNSHINE COULD RESULT IN MODEST SFC BASED INSTABILITY DEVELOPING WHICH COULD ALLOW FOR SCATTERED THUNDERSTORMS TO DEVELOP BY LATE MORNING/EARLY AFTERNOON...ESPECIALLY IN THE VICINITY OF THE NORTHWARD LIFTING WARM FRONT. MANY OF THE VARIOUS CONVECTIVE ALLOWING MODELS ARE DEPICTING CONVECTIVE INITIATION BY LATE MORNING/EARLY AFTERNOON IN THE AREA. WHILE INSTABILITY LOOKS TO BE MODEST...THE AMBIENT VERTICAL VORTICITY IN THE VICINITY OF THE UPPER LOW COMBINED WITH 0-4KM BULK SHEAR VALUES OF 30-40KT (ESPECIALLY EASTERN CWA WHERE BETTER INSTABILITY SHOULD RESIDE) DOES RAISE CONCERNS ABOUT A LOW TOPPED/MINI SUPERCELL SCENARIO POTENTIALLY UNFOLDING TODAY. CONFIDENCE IS LOW AND STORM MOTION SHOULD BE LARGELY PERPENDICULAR TO THE WARM FRONT...SO EVEN IF MINI SUP`S DO MATERIALIZE ANY TORNADO THREAT WOULD BE BRIEF AND VERY LIKELY ON THE LOW END OF THE INTENSITY SPECTRUM BUT SOMETHING TO MONITOR TODAY NONE THE LESS. WARM FRONT SHOULD LIFT NORTH INTO WISCONSIN LATER THIS AFTERNOON WITH POTENTIALLY ANOTHER SIZABLE BREAK IN THE PRECIP THREAT LATER THIS AFTERNOON BEFORE NEXT SHORTWAVE PIVOTS AROUND THE UPPER LOW AND LIKELY BRINGS ADDITIONAL SHOWERS INTO AREA TONIGHT. REALLY IT SHOULD BE THE SAME STORY FOR THE REMAINDER OF THE WORK WEEK WITH OCNL BOUTS OF AT LEAST SCT`D SHOWERS. TIMING THESE INDIVIDUAL IMPULSES PIVOTING AROUND THE WOBBLING UPPER LOW IS DIFFICULT A DAY OR TWO OUT...BUT FAIRLY CONFIDENT THERE WILL BE PERIODIC BOUTS OF AT LEAST SCTD SHOWERS THROUGH THE REST OF THE WEEK WITH DRY HOURS LIKELY OUT NUMBERING RAINY HOURS BY A SIGNIFICANT RATIO. TEMPERATURES TODAY SHOULD HAVE AN OPPORTUNITY TO WARM UP NICELY GIVEN SOME MIXED SUNSHINE AND THE LIMITED WARM AIR ADVECTION THAT WILL TAKE PLACE. OVER TIME THE UPPER COLD POOL WILL SETTLE OVER THE AREA AND SHOULD KEEP SKIES LARGELY CLOUDY AND TEMPERATURES MUCH COOLER AND BELOW AVERAGE THROUGH THE REMAINDER OF THE WORK WEEK. TRANSITION TOWARD DRIER CONDITIONS AND TEMPERATURES GETTING CLOSER TO SEASONAL NORMS. MODEL BLENDED COCKTAIL DID COME UP WITH POPS THROUGH THE WEEKEND AND ATTEMPTED TO BACK OFF SOME BUT RELUCTANTLY WAS LEFT WITH SOME LOW END CHANCES FOR PRECIP THIS WEEKEND IN THE GRIDS/FORECAST...BUT SUSPECT THOSE POPS WILL BE ABLE TO BE PULLED IN THE NEXT DAY OR TWO. IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * ISOLATED SHOWERS THROUGH ARND 11Z...WITH A BREAK IN PCPN POTENTIAL UNTIL TUESDAY AFTERNOON. * ELY-ESELY WINDS 5-10KT THROUGH LATE MORNING...THEN VEERING SLY WITH OCNL GUSTS TO ARND 15KT. * IFR AND OCNL LIFR CIGS UNTIL WARM FRONTAL PASSAGE BTWN 10-12Z. KREIN //DISCUSSION...UPDATED 09Z... LATEST RADAR TRENDS INDICATE THE BULK OF THE PCPN HAS LIFTED NORTH OF THE TERMINALS...BUT IN A VERY MOIST ENVIRONMENT...THERE IS STILL THE CHANCE FOR AN ISOLATED LIGHT SHOWER OR SOME PATCHY DRIZZLE. AS OF 09Z...CIGS HAVE DROPPED TO ANYWHERE FROM 200FT TO 500FT ACROSS THE AREA AS THE WARM FRONT LIFTS NORTH. THE WARM FRONT WAS APPROACHING THE I-80 CORRIDOR AND SLOWLY MOVING NWD WITH CONDITIONS IMPROVING SOUTH OF THE BOUNDARY. ANTICIPATE THAT THE WARM FRONT WILL MOVE THROUGH NRN IL/IN BTWN 10-12Z...WITH WINDS VEERING TO SLY. THE PRESSURE GRADIENT AT THE SFC WILL BE RATHER WEAK WITH AND FOLLOWING THE FROPA...SO ANTICIPATE THAT SUSTAINED SLY WINDS WILL BE AT OR LESS THAN 10KT...WITH PERHAPS A FEW HIGHER GUSTS FROM LATE MORNING AND THROUGH THE EVENING. THERE WILL BE PERIODIC CHANCES FOR SCT SHOWERS WITH MVFR CIGS/VIS AS THE UPPER LOW REMAINS OVER THE MIDWEST...THOUGH COVERAGE AND TIMING WILL HAVE A RELATIVELY LOW CONFIDENCE FACTOR IN THE ABSENCE OF A STRONG FOCUSING MECHANISM. KREIN //ORD AND MDW CONFIDENCE...UPDATED 09Z... * LOW TO MEDIUM CONFIDENCE IN CIG/VIS TRENDS...BUT LOW CONFIDENCE IN THE LOWER EXTENT AND DURATION OF IFR CIGS/VIS FOR THE REMAINDER OF THE OVERNIGHT HOURS. * MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS. KREIN //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY THROUGH SUNDAY...CHANCE OF RAIN EACH DAY...MVFR LIKELY WITH IFR POSSIBLE. LENNING && .MARINE... 300 AM CDT A BROAD AREA OF LOW PRESSURE IS CENTERED OVER SOUTHWESTERN IOWA EARLY THIS MORNING WITH A STRONG WARM FRONT EXTENDING EAST THROUGH CENTRAL ILLINOIS AND INDIANA. A STRONG EASTERLY GRADIENT REMAINS IN PLACE OVER LAKE MICHIGAN AS HIGH PRESSURE REMAINS PARKED OVER SOUTHEASTERN CANADA. AS THE WARM FRONT INCHES NORTHWARD...THE GRADIENT OVER THE LAKE WILL GRADUALLY RELAX FROM SOUTH TO NORTH...WITH WINDS VEERING TO SOUTHEASTERLY AND WEAKENING. HAVE LET THE GALE WARNING FOR THE SOUTHERN PORTIONS OF THE LAKE EXPIRE AS THE GRADIENT OVER THE FAR SOUTHERN PORTIONS OF THE LAKE HAS ALREADY WEAKENED ENOUGH TO LET WINDS SUBSIDE BELOW GALE FORCE...AND EXPECT THIS TREND TO CONTINUE THROUGH THE DAY...WITH WINDS FINALLY DROPPING BELOW GALE FORCE OVER THE NORTHERN PORTIONS OF THE LAKE BY LATE THIS AFTERNOON. AS THE WARM FRONT MOVED NORTH UP THE LAKE...RELATIVELY WARMER AND MOIST AIR WILL OVERSPREAD THE COLDER WATERS OF THE LAKE...WHICK WILL ALLOW FOR AREAS OF FOG TO FORM. THIS FOG MAY BE OCCASIONALLY DENSE...AND WILL CONTINUE CONTINUING THROUGH MID WEEK. WHILE A MORE RELAXED GRADIENT WILL THEN PREVAIL FOR THE REMAINDER OF THIS WEEK ACROSS LAKE MICHIGAN...GENERAL LOW PRESSURE AND BROAD CYCLONIC FLOW WILL STILL PERSIST ACROSS THE GREAT LAKES REGION. WINDS WILL REMAIN AROUND 15 TO 25 KTS THROUGH THE WEEK WITH CONTINUED PERIODS OF UNSETTLED WEATHER AND INTERMITTENT PERIODS OF SHOWERS AND AREAS OF FOG. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ563 UNTIL 4 PM TUESDAY. GALE WARNING...LMZ366-LMZ565-LMZ567-LMZ868 UNTIL 10 AM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 10 AM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion National Weather Service Lincoln IL 351 AM CDT Tue Apr 29 2014 .DISCUSSION... ISSUED 334 AM CDT Tue Apr 29 2014 Upper low over the Missouri River Valley this morning with an occluding sfc low...and occluded front wrapped up all the way over into Central Illinois. Forecast both deceptively simple and problematic. Very little in the way of detail available with the upper low parking over the center of the country and keeping much of the Midwest under the influence of the cyclonic flow. Cloudy, cool, and periodic rain chances will keep ILX in a rather springlike pattern for most of the remains of the week. By the weekend, the upper low ejects to the NE, with Central Illinois in northwesterly flow. Although it is a pattern shift, northwesterly flow is just as dominated by periodic precip. Forecast peppered with pops through Day 7, and cooler than average overall. SHORT TERM...Today and tomorrow... Though models hinting to keep us dry this morning with some drier air on sat imagery, most models quickly get showery again this afternoon under the upper low. With cyclonic flow aloft, any clearing will lend itself to a diurnal shower pattern. Pops in the overnight tonight may be slightly overdone, once the diurnal influence disappears at dusk, but will have to see the wave pattern pushing around the low today to see if another dynamic may hold the showers over into the night hours. Tomorrow is similarly cloudy but even cooler as more cold air builds into the region. Similar afternoon shower potential. Keeping thunder out of the forecast as the low further occludes and loses a bit of potency. Tomorrow night shower pops starting to erode...and maintain the better chances closer to the low center as it begins to drift across the nrn tier of the state and open up. LONG TERM...Thursday through Monday... Cloudy, cool, and another chance of afternoon showers for Thursday, though if the models continue to push the upper low out on Thursday afternoon/evening, that influence may go away and dry out that pd. For Friday through the weekend...Cooler temps and northwesterly flow. Pops are low overall bc there is little consistency from model to model with small wave rippling through the flow aloft. A southerly component to the winds and a building ridge over the Plains slowly bring temps up late in the weekend. HJS && .AVIATION... ISSUED 1148 PM CDT Mon Apr 28 2014 VFR conditions will prevail at the central Illinois terminals tonight through Tuesday afternoon, before MVFR ceilings gradually spread in from the west. Earlier rains have pushed east of the TAF sites late this evening, leaving behind a mid-level overcast and dry conditions. Clouds will tend to thin/dissipate as the night progresses, with partly sunny skies noted by Tuesday morning. Meanwhile, an upper-level low currently centered over eastern Kansas will slowly track eastward, spreading lower clouds and scattered showers into the area toward midday into the afternoon. Based on HRRR and NAM data, have introduced VCSH at KPIA and KSPI by 18z, then further east to KCMI after 22z. While clouds will thicken/lower later in the day, MVFR ceilings will hold off until evening between 00z and 03z. Winds will initially be light from the E/SE tonight, but then will become gusty out of the S/SW on Tuesday. Forecast soundings and numeric guidance suggest gusts of around 20kt across much of the area and in the 20 to 25kt range further east at KCMI. Barnes && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1248 AM CDT TUE APR 29 2014 .DISCUSSION... 230 PM CDT MESOSCALE DISCUSSION FROM 17Z... THE MAIN CONCERNS TODAY CONTINUE TO FOCUS ON THE THREAT FOR STRONG TO SEVERE THUNDERSTORM DEVELOPMENT THIS AFTERNOON. LOW PRESSURE...BOTH AT THE SURFACE AND ALOFT CONTINUE TO BE IN PLACE ACROSS EASTERN SECTIONS OF NEBRASKA TODAY...WHILE THE ASSOCIATED WARM FRONTAL BOUNDARY IS DRAPED EASTWARD ACROSS CENTRAL PORTIONS OF THE STATE. AS OF 16 UTC...THIS FRONT IS LOCATED FROM JUST NORTH OF KSPI...EAST-SOUTHEASTWARD NEAR KDEC AND TO THE NORTH OF KRSV IN CENTRAL ILLINOIS. THIS FRONT IS EXPECTED TO SLOWLY SHIFT NORTHWARD INTO MY FAR SOUTHERN CENTRAL ILLINOIS COUNTIES LATER THIS AFTERNOON. THE AIRMASS TO THE SOUTH OF THIS WARM FRONT FEATURES TEMPERATURES WARMING INTO THE LOWER 70S WITH DEW POINTS GENERALLY NEAR 60 AND LESS CLOUD COVER...WHILE THE TYPICAL LOW IFR CIGS AND EASTERLY COOL FLOW REMAINS IN PLACE NORTH OF THE BOUNDARY. THE EXPECTATIONS ARE THAT A MID LEVEL VORT MAX/IMPULSE AND ASSOCIATED SPEED MAX IN EXCESS OF 70 KT...PER 12 UTC RAOBS OUT OF KSGF AND KLZK AND THE LATEST WATER VAPOR IMAGERY...WILL EJECT EAST-NORTHEASTWARD ACROSS CENTRAL ILLINOIS AND INTO INDIANA LATE THIS AFTERNOON AND EVENING ALONG THE EASTERN PERIPHERY OF THE MID/UPPER LEVEL VORTEX CENTERED ACROSS NEBRASKA. AS THIS OCCURS...INCREASING FORCING FOR ASCENT WILL LIKELY OVERSPREAD THE AREA BY MID TO LATE AFTERNOON LEADING TO THE DEVELOPMENT OF STORMS FROM SOUTHEASTERN IOWA ACROSS CENTRAL PORTIONS OF ILLINOIS. A MID LEVEL COLD POOL...FEATURING 500 MB TEMPERATURES AROUND -18 C...WILL ACCOMPANY THIS MID LEVEL IMPULSE...AND THIS WILL RESULT IN INCREASING LAPSE RATES ACROSS THE AREA. OVERALL...MODEL GUIDANCE CONTINUES TO SUGGEST DEEP LAYER SHEAR WILL BE SUFFICIENT TO SUPPORT SOME SUPER CELLS...AND GIVEN THE STEEPENING LAPSE RATES...THIS AFTERNOON LARGE HAIL WILL LIKELY BE THE GREATEST THREAT WITH THESE STORMS. IT STILL APPEARS THERE COULD BE A SMALL TORNADO THREAT AS WELL ACROSS WEST CENTRAL ILLINOIS IN CLOSER PROXIMATELY TO THE UPPER LOW...WHERE BETTER VERTICAL VORTICITY WILL BE PRESENT. THE MAIN THREAT FOR SEVERE WEATHER STILL APPEARS TO BE MAINLY SOUTH OF INTERSTATE 80...AND THE MAIN TIMING LOOKS TO BE FROM AROUND 3-4 THIS AFTERNOON THROUGH 7-8 PM THIS EVENING. KJB TONIGHT... MAIN CONCERNS FOR THIS EVENING WILL BE POTENTIAL FOR ONGOING STRONG/SEVERE STORMS IN PROXIMITY TO THE FRONTAL BOUNDARY...AND ANY STORMS THAT PASS NORTH OF THE BOUNDARY LIFTING NORTH INTO THE CWFA COULD PRODUCE LARGE DAMAGING HAIL WITH SUCH A STRONGLY SHEARED ENVIRONMENT AND VERY STEEP LAPSE RATES. VISIBLE IMAGERY THIS AFTERNOON HAS EXTENSIVE CLOUD COVER PRODUCING CONSIDERABLE SOLAR SHIELDING FOR THE BULK OF THE CWFA...WHICH KEEPING TEMPS IN CHECK GENERALLY IN THE 50S. THE EXCEPTION IS LOCATIONS ADJACENT TO LAKE MICHIGAN WHERE THE STRONG EAST FLOW HAS HELD TEMPS IN THE UPR 40S. KILX 18Z SOUNDING SHOWS VERY IMPRESSIVE LAPSE RATES...ABOVE THE CAPPED ENVIRONMENT. AN ARC OF STORMS WAS DEVELOPING THIS AFTERNOON FROM SOUTHWEST IOWA STRETCHING SOUTHEAST THROUGH NORTHEAST MISSOURI AND SLOWLY LIFTING NORTH/NORTHWEST. GIVEN THE ENVIRONMENTAL CONDITIONS...MAINLY WITH THE STEEP LAPSE RATES AND FAVORABLE SHEAR THE POSSIBILITY FOR A FEW SUPERCELLS TO DEVELOP. IN ADDITION HELICITY ALONG AND JUST NORTH OF THE FRONTAL BOUNDARY HAS INCREASED...WHICH IS SUGGESTIVE THAT A FEW OF THE STRONGER STORMS COULD BEGIN TO ROTATE. THUS THE THREAT FOR AN ISOLATED TORNADO IS NOT ZERO. THE GREATEST THREAT FROM SEVERE STORMS OVER OUR FORECAST AREA REMAINS DAMAGING WINDS AND LARGE HAIL THOUGH. GUIDANCE CONTINUES TO SUGGEST A DRY WEDGE WILL PUSH NORTHEAST INTO THE CWFA THIS EVENING...WHICH COULD BRING A PERIOD OF DRY WEATHER THIS EVENING. HAVE NOT DEVIATED MUCH FROM EARLIER THINKING...WHICH WAS MAINLY JUST A LOWERING OF POPS TO SUGGEST COVERAGE WILL BE LESS OVERNIGHT. IN ADDITION IT DOES APPEAR THE CONVECTIVE THREAT WILL END ARND MIDNIGHT. TUESDAY THROUGH THURSDAY... 500MB LOW WILL DRIFT EAST ACROSS CENTRAL IOWA TUE MORNING. THE DOMINANT LONGWAVE FEATURE REMAINS THE SFC RIDGE PARKED OVER HUDSON BAY...WHICH HAS REMAINED VERY STRONG. THIS IS CREATING A LOG-JAM...IN THAT THE MID-LVL VORT/SFC LOW WILL NOT BE ABLE TO DEPART THE REGION VERY QUICKLY AND REMAIN QUASI-STATIONARY THROUGH THE MIDDLE OF THE WEEK. WITH SOME HEATING AT THE SFC EXPECTED TUE...AND MID-LVL INSTABILITY...A FEW ISOLATED THUNDERSTORMS COULD DEVELOP. FORTUNATELY THE ENVIRONMENT DOES NOT LOOK CONDUCIVE FOR SEVERE WEATHER TUE AFTN. THEN FOR WED IT LOOKS LIKE THE CONVECTIVE CHANCES WILL BE SHIFTING TO THE EAST OF THE FORECAST AREA. TUE WILL LIKELY BE THE WARMEST DAY IN THE MEDIUM TERM...WITH TEMPS BEING ABLE TO REACH THE LOW/MID 60S. THEN WITH CONSIDERABLE SOLAR SHIELDING WED/THUR TEMPS WILL LIKELY STRUGGLE TO WARM BEYOND THE 50S. CHANCES FOR PRECIP WILL SLOWLY DECREASE THROUGHOUT THE WEEK. FRIDAY THROUGH EARLY NEXT WEEK... ENSEMBLES HAVE BEEN INDICATING A HIGH-AMPLITUDE WAVE DEVELOPING ACROSS ALASKA AND COVERING MUCH OF THE WEST COAST. THIS SUGGESTS THAT THE GREAT LAKES REGION WILL SEE TROUGHING FOR THE UPCOMING WEEKEND...THEN A SLOW RELAXING OF THE TROUGH INTO A QUASI-ZONAL FLOW FOR EARLY NEXT WEEK. GUIDANCE INDICATES THAT A PERIOD OF DRY WEATHER SHOULD DEVELOP OVER THE FORECAST AREA FOR A PORTION OF THE WEEKEND...THEN A WEAK WAVE IS PROGGED TO QUICKLY SLIDE SOUTHEAST ACROSS THE UPPER MIDWEST LATER IN THE WEEKEND AND COULD BRING ANOTHER CHANCE FOR SHOWERS TOWARDS THE END OF THE WEEKEND INTO EARLY NEXT WEEK. TEMPS FOR THE WEEKEND WILL SLOWLY RETURN TO NEAR SEASONAL CONDITIONS. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * SCATTERED SHOWERS THROUGH ARND 09Z...WITH A BREAK IN PCPN POTENTIAL UNTIL TUESDAY AFTERNOON. * ELY-ESELY WINDS ARND 10KT THROUGH LATE MORNING...THEN VEERING SLY WITH OCNL GUSTS TO ARND 15KT. * VARIABLE CIGS BTWN VFR AND MVFR. OCNL BRIEF PERIODS IFR CIGS POSSIBLE THROUGH ARND 10Z. KREIN //DISCUSSION...UPDATED 06Z... THUNDERSTORMS HAVE PUSHED WELL EAST OF THE TERMINALS...BUT SCATTERED SHOWERS ASSOCIATED WITH A BROAD...DEEP UPPER LOW WILL CONTINUE FOR THE NEXT FEW HOURS. LATEST RADAR TRENDS INDICATE SCATTERED AREAS OF PCPN MOVING NWD DRIVEN BY STRONG SLY FLOW ALOFT...BUT A WARM FRONT REMAINS TO THE SOUTH OF THE TERMINALS...SO SFC WINDS WILL CONTINUE TO BE ELY-ESELY UNTIL THE WARM FRONT PUSHES NWD. AT ISSUANCE TIME...THE WARM FRONT IS STILL THROUGH CNTRL IL/IN...BUT SLOWLY MOVING NWD. CIGS WILL REMAIN A CONCERN WHILE THE WARM FRONT REMAINS SOUTH OF THE TERMINALS. THERE ARE POCKETS OF IFR CIGS OVER THE AREA...WITH RFD/DPA/GYY STARTING OUT THE PERIOD WITH IFR CIGS. THERE WILL BE A CHANCE FOR PERIODS OF CIGS LOWERING INTO IFR AT ORD/MDW...BUT TIMING AND DURATION REMAIN UNCERTAIN...SO WILL KEEP CIGS AT LOWER END MVFR AT ORD/MDW FOR NOW...THOUGH AMENDMENTS ARE CERTAINLY POSSIBLE. ANTICIPATE THAT THE WARM FRONT WILL MOVE THROUGH NRN IL/IN BTWN 12-15Z...WITH WINDS VEERING TO SLY. THE PRESSURE GRADIENT AT THE SFC WILL BE RATHER WEAK WITH AND FOLLOWING THE FROPA...SO ANTICIPATE THAT SUSTAINED SLY WINDS WILL BE AT OR LESS THAN 10KT...WITH PERHAPS A FEW HIGHER GUSTS FROM LATE MORNING AND THROUGH THE EVENING. THERE WILL BE PERIODIC CHANCES FOR SCT SHOWERS WITH MVFR CIGS/VIS AS THE UPPER LOW REMAINS OVER THE MIDWEST...THOUGH COVERAGE AND TIMING WILL HAVE A RELATIVELY LOW CONFIDENCE FACTOR IN THE ABSENCE OF A STRONG FOCUSING MECHANISM. KREIN //ORD AND MDW CONFIDENCE...UPDATED 06Z... * LOW TO MEDIUM CONFIDENCE IN CIG/VIS TRENDS...BUT LOW CONFIDENCE IN TIMING AND DURATION OF IFR CIGS/VIS FOR THE REMAINDER OF THE OVERNIGHT HOURS. * MEDIUM TO HIGH CONFIDENCE IN PERIODS OF SCT SHRA...BUT LOW CONFIDENCE IN TIMING AND COVERAGE. * MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS. KREIN //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY THROUGH SUNDAY...CHANCE OF RAIN EACH DAY...MVFR LIKELY WITH IFR POSSIBLE. LENNING && .MARINE... 303 PM CDT STRONG LOW PRESSURE OVER EASTERN NEBRASKA WILL MOVE ONLY VERY SLOWLY EASTWARD TONIGHT AND TUESDAY REACHING NORTHERN ILLINOIS TUESDAY NIGHT. A WARM FRONT ASSOCIATED WITH THIS LOW WILL PIVOT NORTH ACROSS LAKE MICHIGAN TONIGHT LYING WEST-EAST ACROSS THE CENTRAL PART OF THE LAKE BY LATE TUESDAY. GALE FORCE WINDS WILL EXTEND INTO THE OVERNIGHT TONIGHT ACROSS THE NORTH HALF OF THE LAKE AS THE PRESSURE GRADIENT STRENGTHENS OVER THIS REGION NORTH OF THE WARM FRONT.... AND AS VERY STRONG HIGH PRESSURE REMAINS ANCHORED OVER FAR NORTHERN QUEBEC. MEANWHILE GALE FORCE WINDS WILL RELAX AFTER EARLY EVENING AS AS THE WARM FRONT APPROACHES AND LIFTS NORTH FROM THE SOUTH ACROSS SOUTHERN LAKE MICHIGAN. THE RELATIVELY WARM AND MOIST AIRMASS MOVING OVER THE COLDER WATERS OF THE LAKE WILL ALSO ALLOW FOR AREAS OF FOG TO FORM... OCCASIONALLY DENSE... CONTINUING THROUGH MID WEEK. WHILE A MORE RELAXED GRADIENT WILL THEN PREVAIL FOR THE REMAINDER OF THE WEEK WEDNESDAY INTO SATURDAY ACROSS LAKE MICHIGAN... LOW PRESSURE AND BROAD CYCLONIC FLOW WILL STILL PERSIST ACROSS THE GREAT LAKES REGION. WINDS WILL REMAIN AROUND OR BELOW 25 KTS LATE WEEK HOWEVER WITH CONTINUED UNSETTLED WEATHER WITH INTERMITTENT PERIODS OF SHOWERS AND AREAS OF FOG. ED F && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM TUESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 9 AM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1148 PM CDT Mon Apr 28 2014 .DISCUSSION... ISSUED 900 PM CDT Mon Apr 28 2014 Line of convection has pushed east of the I-55 corridor and weakened considerably this evening as it encountered a more stable airmass across east-central Illinois. 01z/8PM surface analysis shows 992mb low over western Iowa, with warm frontal boundary extending eastward across the far northern KILX CWA. Meanwhile, a cold front/dryline is analyzed arcing southeastward from the low to near I-55. Showers/storms will continue ahead of the dryline for the next couple of hours before diminishing and pushing into Indiana around midnight. Updated the forecast to better reflect hourly temps and expected POP trends for the remainder of the night. New zones have already been sent. Barnes && .AVIATION... ISSUED 1148 PM CDT Mon Apr 28 2014 VFR conditions will prevail at the central Illinois terminals tonight through Tuesday afternoon, before MVFR ceilings gradually spread in from the west. Earlier rains have pushed east of the TAF sites late this evening, leaving behind a mid-level overcast and dry conditions. Clouds will tend to thin/dissipate as the night progresses, with partly sunny skies noted by Tuesday morning. Meanwhile, an upper-level low currently centered over eastern Kansas will slowly track eastward, spreading lower clouds and scattered showers into the area toward midday into the afternoon. Based on HRRR and NAM data, have introduced VCSH at KPIA and KSPI by 18z, then further east to KCMI after 22z. While clouds will thicken/lower later in the day, MVFR ceilings will hold off until evening between 00z and 03z. Winds will initially be light from the E/SE tonight, but then will become gusty out of the S/SW on Tuesday. Forecast soundings and numeric guidance suggest gusts of around 20kt across much of the area and in the 20 to 25kt range further east at KCMI. Barnes && .PREV DISCUSSION... ISSUED 317 PM CDT Mon Apr 28 2014 Main concerns will be storms developing over the area and moving in from the west this afternoon and early tonight. Then the concern will shift and become the continue chances of diurnal precip for the rest of the week as the upper level low slowly drifts eastward into the Great Lakes region later this week. Models look ok with the overall pattern and sfc features through the period. Only differences seen will be in the mesoscale features for rest of the afternoon and into tonight. SHORT TERM...Tonight through Thursday Tornado watch continues til 7pm as storms have fired on the dry line in MO early this afternoon. These storms will be moving northeast and northerly during the period over the western parts of the area. Hail appears to be the main threat right now, but isolated tornadoes will also be possible if the storms begin to rotate. The storms are low-topped and will remain that way. Thunderstorms will be possible again tomorrow as the upper level low will still be northwest of the area, though closer than today. Severe weather is not expected tomorrow as the best moisture will have moved east of the area. Skies will also be cloudy south of the low system, so instability will be quite low. Then diurnal showers will be possible remainder of the period as the the forecast area remains in cyclonic flow through the week. This flow will also have temps much cooler through the period. LONG TERM...Thursday night through Monday Cyclonic flow continues through the rest of the week and into the weekend. Then by end of the weekend, the system will push out of the area. We will finally have some dry periods as high pressure builds in for a brief period. Then another system is expected to move into the area for Sunday. Temps will remain on the cool side through the period. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
141 AM EDT TUE APR 29 2014 .UPDATE... ISSUED AT 141 AM EDT TUE APR 29 2014 AS OF 0530Z...SHOWERS AND THUNDERSTORMS CONTINUE TO STREAM INTO THE AREA FROM THE SOUTHWEST. STILL HAVE LIKELY TO CAT POPS IN THE FORECAST AND DESPITE SOME TEMPERATURE DIFFERENCES...THE FORECAST LOOKS TO BE ON TRACK. WILL BE FRESHENING UP THE POP FORECAST IN THE NEXT COUPLE OF THE HOURS FOR THE MORNING PACKAGE AND SEND OUT A NEW ZFP THEN. THE GRIDS HAVE BEEN SENT TO NDFD SERVERS. UPDATE ISSUED AT 1115 PM EDT MON APR 28 2014 SHOWERS AND THUNDERSTORMS CONTINUE TO GRADUALLY MOVE NORTHEAST TOWARD EASTERN KENTUCKY. MODEL GUIDANCE INDICATES THE BAND OF CONVECTION MOVING ACROSS THE AREA OVERNIGHT AND A QUICKER TAPERING OFF FROM WEST TO EAST TOWARD DAWN THAN THE PREVIOUS FORECAST. HOWEVER...SOUTHEAST FLOW ESPECIALLY INTO OUR EASTERN COUNTIES SEEMS TO BE LIMITING THE EASTWARD PROGRESS. ALSO... INSTABILITY DECREASES TO THE EAST AND NORTHEAST. AT THIS POINT... SOME STRONG STORMS APPEAR POSSIBLE...MAINLY ACROSS THE WESTERN PART OF THE CWA AND LOCALLY HEAVY RAIN MAY BE THE PRIMARY THREAT FOR THE DURATION OF THE NIGHT. THE FURTHER EAST AND SOUTHEAST...THE DOWNSLOPE FLOW SHOULD CUT INTO RAINFALL AMOUNTS. THE SOUTH SOUTHEAST FLOW ON THE HIGHER TERRAIN NEAR VA COULD BE GUSTY AT TIMES AND SOME GUSTS AS HIGH AS 30 TO 40 MPH WILL BE POSSIBLE... WITH SUSTAINED WINDS IN THE 15 TO 25 MPH RANGE AT TIMES. UPDATE ISSUED AT 655 PM EDT MON APR 28 2014 THE LULL CONTINUES WITH THE STORMS. JKL AWAITS THE DEVELOPMENT FROM THE WEST AND THEN A PUSH EAST THROUGH THE NIGHT PER THE LATEST RAP AND HRRR MODELS. AS SUCH...HAVE DROPPED THE TORNADO WATCH IN THE FAR SOUTHEAST. ANY REAL THREAT OF SEVERE WEATHER WILL HOLD OFF UNTIL LATER IN THE EVENING. HAVE UPDATED THE POPS/WX GRIDS TO REFLECT THIS TIMING AND ALSO FINE TUNED THE T/TD ONES BASED ON THE LATEST OBS AND TRENDS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 425 PM EDT MON APR 28 2014 19Z SFC ANALYSIS SHOWS THE DEEP AREA OF LOW PRESSURE SPINNING OVER THE CENTRAL PLAINS. THIS SYSTEM/S WARM FRONT IS LAID OUT TO THE EAST JUST NORTH OF THE OHIO RIVER. THIS PLACES EAST KENTUCKY WELL INTO TO THE BROAD WARM SECTOR AND THUS RIPE FOR PERIODS OF SHOWERS AND THUNDERSTORMS. EARLIER SUNSHINE IN THE FAR EAST LED TO WARMER TEMPERATURES AND THIS IS HELPING STORMS SUSTAIN THEMSELVES NEAR THE VIRGINIA BORDER. MEANWHILE...MUCH COOLER TEMPERATURES IN THE REST OF THE CWA...DUE TO THE COLD POOL FROM THE EARLIER MCS TO THE WEST AND MORE EXTENSIVE CLOUD COVER...HAS KEPT THE CONVECTION TAME THERE...FOR NOW. DEWPOINTS REMAIN IN THE UPPER 50S TO LOWER 60S THROUGHOUT THE AREA WHILE THE WINDS ARE RATHER VARIABLE WITH OCCASIONAL SOUTH TO SOUTHWEST GUSTS TO 20 KTS...OUTSIDE OF STORMS. THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE DEEP UPPER LOW TRANSITIONING INTO THE MID MISSISSIPPI VALLEY TONIGHT AND SPREADING WAVES OF ENERGY CLUSTERS OVER EAST KENTUCKY AS IT DOES SO. THE BROAD CLOSED LOW THEN LIFTS NORTH INTO THE WESTERN GREAT LAKES LATER TUESDAY WHILE ONE LAST BATCH OF ENERGY RIDES THROUGH KENTUCKY DURING THE NIGHT. GIVEN THE MODEL AGREEMENT...HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE NAM12 AND HRRR FOR THE NEAR TERM DETAILS. SENSIBLE WEATHER WILL FEATURE PERIODS OF SHOWERS AND THUNDERSTORMS THROUGH THE SHORT TERM PORTION OF THE FORECAST. EACH NEW CLUSTER WILL HAVE A CHANCE TO BECOME SEVERE DEPENDING ON THE INSTABILITY LEFT BEHIND BY EARLIER STORMS AND CLEARING THAT CAN TAKE PLACE DURING THE DAYLIGHT HOURS. THIS WAS WHAT SET UP THE STORMS FOR FAR EAST KENTUCKY THIS AFTERNOON. EXPECT THESE TO CLEAR OUT OVER THE NEXT HOUR OR SO. ABOUT THAT TIME...THE NEXT ROUND OF STORMS SHOULD BE DEVELOPING IN SOUTH CENTRAL KENTUCKY AND WORKING TO MOVE NORTHEAST INTO EAST KENTUCKY LATER IN THE EVENING. STORMS WILL CONTINUE THROUGH THE NIGHT AS THE SET UP REMAINS INTACT. THE ACTUAL COVERAGE AND TIMING OF THESE LATER EVENTS WILL BE PARTIALLY DEPENDENT ON THE EARLIER EVOLUTION SO IT BECOMES HARDER TO PIN POINT. DO EXPECT THIS OVERNIGHT WAVE OF STORMS TO MOVE ON THROUGH TOWARDS DAWN AND EARLY TUESDAY MORNING IN FAR EASTERN PARTS OF THE STATE. ISOLATED TRAINING AND HEAVY RAINS WILL BE POSSIBLE THROUGH THE NIGHT...POSSIBLY RESULTING IN A FLASH FLOOD THREAT. THIS WILL CONTINUE TO BE HIGHLIGHTED IN THE HWO AND SPS. AFTER A MIDDAY LULL ON TUESDAY...LOW TOPPED STORMS SHOULD DEVELOP ACROSS EAST KENTUCKY BY LATE AFTERNOON WITH A CONTINUING POTENTIAL TO BE SEVERE...INCLUDING A SLIGHT TORNADO THREAT DUE TO FAVORABLE WIND SHEAR IN THE LOW LEVELS. THE MORE SUNSHINE THAT MANAGES TO OCCUR DURING THE DAY TUESDAY WILL PLAY INTO HOW STRONG THE STORMS COULD BECOME. THE SYSTEM/S COLD FRONT WILL SWEEP THROUGH LATER THAT NIGHT AND SHOULD END THE RISK FOR SEVERE WEATHER AND ALSO WIND DOWN THE THUNDER CHANCES. USED THE CONSSHORT AS A STARTING POINT FOR THE GRIDS THROUGH THE NEXT 24 HOURS WITH THE CONSALL THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE NUMBERS MAINLY TO CAPTURE THE CURRENT CONDITIONS AND TRENDS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL GUIDANCE THROUGH THE FORECAST. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 330 PM EDT MON APR 28 2014 MODELS REMAIN IN GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER AIR PATTERN THROUGH THE MIDDLE AND END OF THE WEEK. THE LARGE UPPER LOW OVER THE UPPER MS VALLEY WILL MAKES ITS WAY INTO THE GREAT LAKES REGION BY THURSDAY...AND THEN ON INTO CANADA BY FRIDAY. AFTER THIS THERE WILL BE OCCASIONAL SHORT WAVE TROUGHS PASSING BY AS A MEAN LONG WAVE TROUGH REMAINS OVER THE EASTERN PART OF THE U.S. INTO EARLY NEXT WEEK. IT DOES APPEAR THE FLOW WILL BE SLOWLY DEAMPLIFYING THOUGH. HIGHER RAIN AND THUNDERSTORMS CHANCES WILL LINGER INTO THE DAY WEDNESDAY...MAINLY IN THE EASTERN PART OF THE FORECAST AREA. THE DEEPER MOISTURE AND FORCING WILL BE EXITING THE AREA ON WEDNESDAY...BUT MAINLY DIURNAL SHOWER CHANCES WILL LINGER INTO THE WEEKEND. WITH A MEAN TROUGH OVER THE AREA TEMPERATURES WILL ALSO AVERAGE BELOW NORMAL FOR THE END OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL BE WARMING LATE IN THE WEEKEND AND INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 141 AM EDT TUE APR 29 2014 EXPECT TEMPORARY MVFR TO IFR CONDITIONS HEADING INTO THE MORNING HOURS THROUGH MUCH OF EASTERN KENTUCKY AND THE TAF SITES. WILL PIN POINT TIMES OF WORST CONDITIONS IN THE 09Z TO 15Z TIME FRAME BEFORE SHOWING VFR CONDITIONS THIS AFTERNOON. THOUGH THROUGH THIS TIME...THERE STANDS THE CHANCE OF A VICINITY THUNDERSTORM PASSING BY ONE OF THE TAF SITES. A NEW CLUSTER OF STORMS IS EXPECTED BY THE LAST 6 HOURS OF THE TAF PERIOD OVER MOST OF THE TAF SITES. THIS WILL LEAD TO MVFR TO IFR CONDITIONS. OTHERWISE FOR WINDS...MAINLY OUT OF THE SOUTHEAST SWITCHING AROUND TO THE SOUTHWEST AND WEST BY THE END OF THE PERIOD WITH A FEW GUSTS TO 20 KNOTS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...GREIF LONG TERM...SBH AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
522 AM EDT TUE APR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 520 AM EDT TUE APR 29 2014 WV IMAGERY AND RUC ANALYSIS REVEALS REX BLOCK PATTERN OVER THE CENTRAL PORTION OF NORTH AMERICA WITH A HIGH OVER HUDSON BAY AND AN OCCLUDING CLOSED LOW OVER THE IOWA/MISSOURI BORDER. AT THE SFC...A FEW SITES WERE REPORTING GUSTY EAST TO NORTHEAST WINDS AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER NW MISSOURI. BOTH KCMX AND KMNM WERE REPORTING WIND GUSTS TO NEAR 40 MPH AT TIMES EARLY THIS MORNING. A BAND OF RAIN OVER NORTHERN LAKE MI AND SE UPPER MI SUPPORTED BY 295K-300K ISENTROPIC ASCENT WAS MAKING VERY SLOW NORTHWARD PROGRESS AS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 750 MB) TO THE NORTH AND EAST...PER 00Z APX SOUNDING. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...INCREASING 295K ISENTROPIC ASCENT WILL FINALLY OVERCOME LOW-LVL DRY AIR AND ALLOW PCPN TO SPREAD FROM SCNTRL/SE CWA NORTH AND WEST ACROSS THE REST OF WEST AND CENTRAL UPPER MI LATER THIS MORNING AND AFTERNOON. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE HEAVIER PCPN WILL COINCIDE WITH TROWAL REGION NORTH OF THE MID/UPPER LOW AS NOTED ON MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TONIGHT. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS THERE. SOME UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET- BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE WRN INTERIOR THIS MORNING...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE FAR WEST TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE SNOW ACCUMULATION TO AN INCH OR MAYBE TWO TOWARD KIWD WITH MOST ACCUMULATION ON GRASSY OR SNOW COVERED AREAS. WITH MODELS SHOWING SHORTWAVE AND ASSOC TROWAL REGION LIFTING NORTH AND WEST OF THE FCST AREA TONIGHT ALONG WITH CORRESPONDING WEAKENING OF ISENTROPIC ASCENT AND TRANSITION TO MID-LVL Q-VECT DIVERGENCE... LOOK FOR HEAVIER PCPN TO TAPER OFF AND BECOME MORE LIGHT AND SCATTERED WITH MOST LOCATIONS SEEING BTWN .1 TO .2 INCH. WITH WARMING LOW-LVLS AS NOTED ON SOUNDINGS AND RISING 1000-850 MB THICKNESSES WOULD EXPECT PTYPE MOSTLY RAIN TONIGHT. AREA RIVERS AND STREAMS WILL NEED TO BE MONITORED CLOSELY OVER THE NEXT SEVERAL DAYS AS RUNOFF FROM PCPN AND SNOWMELT WILL LEAD TO RISING RIVER LEVELS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER TEMPS IF MODELS VERIFY WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 203 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL PREVAIL UNTIL TUE MORNING AT ALL SITES. INCREASING MOISTURE AHEAD OF A WARM FRONT WILL BRING AN INCREASING CHANCE OF RAIN AND SNOW TUE MORNING INTO TUE AFTERNOON AT ALL TAF SITES AS CIGS LOWER TO LIFR AND REMAIN LIFR INTO TUE EVENING. SAW HAS DECOUPLED SO PUT LLWS IN FOR THE OVERNIGHT HOURS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT TUE APR 29 2014(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 423 PM EDT MON APR 28 2014 AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER CENTRAL PLAINS AND THE STRONG HIGH OVER HUDSON BAY EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE EVENING. THESE WINDS WILL ALSO BE ENHANCED BY CHANNELING BETWEEN THE KEWEENAW PENINSULA AND ISLE ROYALE. A FEW ENE GALE FORCE GUSTS TO 35 KNOTS ARE ALSO POSSIBLE OVER CENTRAL LAKE SUPERIOR MAINLY THIS MORNING BUT SUSTAINED GALES ARE NOT EXPECTED SO WATCH HEADLINE HAS BEEN DROPPED. THE WINDS WILL DIMINISH THIS EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO SAT AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...07 MARINE...VOSS HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
503 AM EDT TUE APR 29 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 423 PM EDT MON APR 28 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A NEGATIVE TILT MID/UPPER LEVEL TROUGH FROM THE NRN ROCKIES TO THE CENTRAL PLAINS AND MID MS VALLEY. DOWNSTREAM A RIDGE EXTENDED FROM THE MID ATLANTIC THROUGH THE ERN LAKES TO WRN HUDSON BAY. AT THE SFC...GUSTY EAST WINDS PREVAILED AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER ERN NEBRASKA. A BAND OF RAIN OVER NRN WI SUPPORTED BY 295K-300K ISENTROPIC LIFT WAS MAKING VERY SLOW PROGRESS IN LIFTING TO THE NORTH AS IT ENCOUNTERS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 800 MB) TO THE NORTH AND EAST...PER 12Z APX SOUNDING. SOME PCPN MAY DEVELOP ALONG THE WI BORDER THIS EVENING BUT SINCE IT SHOULD BE RELATIVELY LIGHT...MAINLY SPRINKLES...ONLY CHANCE POPS WERE INCLUDED. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...EXPECT WIDESPREAD PCPN TO SPREAD INTO THE SOUTH LATE TONIGHT AND ACROSS THE REST OF THE CWA TUE MORNING. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE REGION WILL FALL UNDER THE TROWAL REGION NORTH OF THE MID/UPPER LOW...PER MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TUE. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS. UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE INTERIOR...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE WRN THIRD TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE ANY ACCUMULATIONS WITH SNOW AMOUNTS ONLY TO AROUND AN INCH EXPECTED ON GRASSY OR SNOW COVERED AREAS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER TEMPS IF MODELS VERIFY WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 203 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL PREVAIL UNTIL TUE MORNING AT ALL SITES. INCREASING MOISTURE AHEAD OF A WARM FRONT WILL BRING AN INCREASING CHANCE OF RAIN AND SNOW TUE MORNING INTO TUE AFTERNOON AT ALL TAF SITES AS CIGS LOWER TO LIFR AND REMAIN LIFR INTO TUE EVENING. SAW HAS DECOUPLED SO PUT LLWS IN FOR THE OVERNIGHT HOURS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 423 PM EDT MON APR 28 2014 EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE INTO TUE EVENING AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER ERN NEBRASKA AND A STRONG HIGH OVER HUDSON BAY. ENE GALES TO 35 KNOTS ARE ALSO POSSIBLE CENTRAL LAKE SUPERIOR TUE BUT SINCE THERE WAS STILL UNCERTAINTY WHETHER THE 30 KNOTS WINDS WILL INCREASE TO GALES...THE WATCH WAS RETAINED FOR THIS LOCATION. THE WINDS WILL DIMINISH TUE EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO FRI AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
208 AM EDT TUE APR 29 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 423 PM EDT MON APR 28 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A NEGATIVE TILT MID/UPPER LEVEL TROUGH FROM THE NRN ROCKIES TO THE CENTRAL PLAINS AND MID MS VALLEY. DOWNSTREAM A RIDGE EXTENDED FROM THE MID ATLANTIC THROUGH THE ERN LAKES TO WRN HUDSON BAY. AT THE SFC...GUSTY EAST WINDS PREVAILED AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER ERN NEBRASKA. A BAND OF RAIN OVER NRN WI SUPPORTED BY 295K-300K ISENTROPIC LIFT WAS MAKING VERY SLOW PROGRESS IN LIFTING TO THE NORTH AS IT ENCOUNTERS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 800 MB) TO THE NORTH AND EAST...PER 12Z APX SOUNDING. SOME PCPN MAY DEVELOP ALONG THE WI BORDER THIS EVENING BUT SINCE IT SHOULD BE RELATIVELY LIGHT...MAINLY SPRINKLES...ONLY CHANCE POPS WERE INCLUDED. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...EXPECT WIDESPREAD PCPN TO SPREAD INTO THE SOUTH LATE TONIGHT AND ACROSS THE REST OF THE CWA TUE MORNING. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE REGION WILL FALL UNDER THE TROWAL REGION NORTH OF THE MID/UPPER LOW...PER MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TUE. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS. UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE INTERIOR...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE WRN THIRD TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE ANY ACCUMULATIONS WITH SNOW AMOUNTS ONLY TO AROUND AN INCH EXPECTED ON GRASSY OR SNOW COVERED AREAS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 423 PM EDT MON APR 28 2014 MUCH OF THE LONG TERM FORECAST WILL DEAL WITH THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS THAT WILL GRADUALLY LIFT NORTHEAST THROUGH MUCH OF THE REST OF THE WORK WEEK. THE STRONGEST WAVE OF PRECIPITATION WILL MOVE NORTH THROUGH THE AREA ON TUESDAY AND SHOULD BE SITUATED OVER WESTERN LAKE SUPERIOR AND THE WESTERN THIRD OF THE U.P. AT THE START OF THE LONG TERM PERIOD. THIS WILL CONTINUE TO ROTATE NORTHWEST TUESDAY NIGHT AND LEAD TO A LITTLE BIT OF A BREAK ON THE PRECIPITATION FOR TUESDAY EVENING OVER THE CENTRAL/EAST. AS THE SURFACE LOW MOVES UP INTO THE GREAT LAKES REGION...A MID LEVEL TROUGH WILL SLIDE NORTH THROUGH THE AREA LATE TUESDAY NIGHT THROUGH WEDNESDAY. THINK THE HEAVIEST PRECIP WOULD BE OVER THE EAST THIRD...BUT STILL WOULD EXPECT SCATTERED/NUMEROUS SHOWERS OVER THE WEST/CENTRAL. BETTER DEEP MOISTURE SHIFTS OVER THE WESTERN LAKE AFTER THAT...AND WILL LIKELY LEAD TO A MORE SCATTERED NATURE TO THE SHOWERS. THIS WILL CONTINUE THROUGH THE FIRST PART OF THE WEEKEND AS THE AS THE UPPER LOW SPINS AND BROADENS/WEAKENS. THUS...WILL CONTINUE TO SHOW A GRADUAL DECREASING TREND TO THE POPS. WITH THE POTENTIAL FOR WEAK DISTURBANCES ROTATING THROUGH...THERE MAY BE PERIODS WHERE POPS NEED TO BE BUMPED UP...BUT PINNING THOSE DOWN AT THIS TIME IS TOO DIFFICULT. AS FOR PRECIP TYPE...SHOULD BE ENOUGH WARM AIR WRAPPING IN DURING THE DAY TOMORROW TO CHANGE THE PRECIP OVER TO RAIN OVER MUCH OF THE AREA BY TUESDAY EVENING (EXCEPT FOR A LINGERING MIX NEAR IRONWOOD). THE WARM AIR CONTINUES TO MOVE WEST AROUND THE LOW (REMAINING AROUND 2-4C AT 850MB) THROUGH WEDNESDAY EVENING AND WILL KEEP EVERYTHING AS RAIN. THEN AS THE FLOW STARTS TO BECOME A LITTLE MORE NORTHERLY ON WEDNESDAY NIGHT AND INTO THURSDAY...TEMPERATURES ALOFT BEGIN TO COOL FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA AND COULD LEAD TO A TRANSITION TO TO MORE OF A RAIN/SNOW MIX HEADING INTO THURSDAY/FRIDAY. OPTED TO FOLLOW THE GENERAL IDEA SHOWN BY THE 1000-850MB THICKNESS AND WETBULB0 HEIGHTS THROUGH THE FORECAST PERIOD SINCE IT WAS LARGELY DEALING WITH A NEAR SURFACE WARM LAYER. DID PUT IN SOME FOG FOR THE FAVORED UPSLOPE HIGHER TERRAIN LOCATIONS OF THE CENTRAL/NORTH-CENTRAL ON TUESDAY NIGHT INTO WEDNESDAY WITH THE FAVORABLE EASTERLY UPSLOPE FLOW OF MOIST AIR. ELSEWHERE...WOULD EXPECT IT TO BE JUST A LOW STRATUS DECK. ALL IN ALL...LOOKS TO BE A COOL/CLOUDY/SHOWERY PERIOD THROUGH THE FIRST HALF OF THE WEEKEND. UPPER TROUGH/LOW FINALLY SHIFTS EAST OF THE AREA FOR THE SECOND HALF OF THE WEEKEND...BUT MODELS DIFFER ON EVOLUTION OF THE UPPER LEVEL PATTERN AT THAT POINT. THE GENERAL IDEA IS FOR MORE ZONAL FLOW OR WEAK UPPER LEVEL RIDGING TO DEVELOP OVER THE NORTH-CENTRAL CONUS...WHICH SHOULD LEAD TO A LITTLE DRIER PERIOD THAN SEEN THIS WEEK. THERE ARE HINTS IN THE 12Z GEM/GFS/ECMWF THAT A WEAK DISTURBANCE WILL SHIFT EAST ACROSS THE AREA ON SUNDAY AND BRING SOME SHOWERS. OTHERWISE...MONDAY IS LOOKING LIKE IT MAY END UP DRY WITH THE WEAK UPPER RIDGE SHIFTING CLOSER TO THE AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 203 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL PREVAIL UNTIL TUE MORNING AT ALL SITES. INCREASING MOISTURE AHEAD OF A WARM FRONT WILL BRING AN INCREASING CHANCE OF RAIN AND SNOW TUE MORNING INTO TUE AFTERNOON AT ALL TAF SITES AS CIGS LOWER TO LIFR AND REMAIN LIFR INTO TUE EVENING. SAW HAS DECOUPLED SO PUT LLWS IN FOR THE OVERNIGHT HOURS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 423 PM EDT MON APR 28 2014 EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE INTO TUE EVENING AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER ERN NEBRASKA AND A STRONG HIGH OVER HUDSON BAY. ENE GALES TO 35 KNOTS ARE ALSO POSSIBLE CENTRAL LAKE SUPERIOR TUE BUT SINCE THERE WAS STILL UNCERTAINTY WHETHER THE 30 KNOTS WINDS WILL INCREASE TO GALES...THE WATCH WAS RETAINED FOR THIS LOCATION. THE WINDS WILL DIMINISH TUE EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO FRI AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 423 PM EDT MON APR 28 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TUESDAY MORNING THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN LATER THIS WEEK AS A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECT UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR LSZ264>266. GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB HYDROLOGY...SRF/TITUS
AREA FORECAST DISCUSSION
NWS DULUTH MN
1229 AM CDT TUE APR 29 2014 .UPDATE... ISSUED AT 1010 PM CDT MON APR 28 2014 MADE VERY LITTLE CHANGES AFTER PREVIOUS CHANGES TO CHASE THE MIXED PRECIPITATION. PRECIPITATION LOCATION AND TYPE HAVE BEEN DIFFICULT TONIGHT. WHILE CLOQUET AND WEST DULUTH HAVE BEEN GETTING SNOW, THEN RAIN, THEN SLEET, THEN SNOW. HERE AT THE AIRPORT WE HAD SLEET, BUT HAVEN`T HAD ANY PRECIPITATION FOR 4 HOURS. BUT SLEETING JUST SOUTHWEST OF THE NWS AT ADOLPH. VERY TIGHT GRADIENT. PCPN AREA IS JUST ALONG OR NORTH OF US HIGHWAY 2 IN MN AND VERY GENERALLY ALONG 2 IN WI. NORTH OF THE PCPN DEW POINTS ARE IN THE TEENS. SOUTH..THEY ARE IN THE 30S. SO THE DRY AIR IS WINNING FOR NOW. WILL NOT MAKE CHANGES TO TUESDAY ATTM,..BUT INTERESTING TO SEE BOTH THE LOCAL WRF AND HRRR KEEPING MUCH OF THE NORTHERN HALF OF NORTHLAND DRY THROUGH TUESDAY MORNING. ANOTHER AREA OF MOISTURE WILL BE MOVING INTO THE REGION FROM THE SOUTH LATER TONIGHT SO WILL LEAVE POPS AS ARE. UPDATE ISSUED AT 443 PM CDT MON APR 28 2014 UPDATED TO ADD SLEET AS HAS BEEN OCCURRING IN THE DULUTH AREA FOR PAST HOUR. && .SHORT TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 315 PM CDT MON APR 28 2014 AT 315PM/2015Z...THERE WAS A LOW PRESSURE SYSTEM CENTERED OVER EASTERN NEBRASKA. MUCH OF THE UPPER MIDWEST AND PLAINS HAD CLOUDY SKIES DUE TO THIS SYSTEM. HIGH PRESSURE WAS CENTERED EAST OF HUDSON BAY. MUCH OF THE SOUTHERN AND AND WESTERN FORECAST AREA HAD LIGHT TO MODERATE RAIN MOVING THROUGH THE REGION. THE NORTHLAND HAD GUSTY EAST TO NE WINDS. THE WINDS WERE PARTICULARLY STRONG OVER WESTERN LAKE SUPERIOR AND NEAR THE TWIN PORTS AREA. THE TWIN PORTS AREA WAS SEEING SUSTAINED WINDS OF 25 TO 35 MPH WITH GUSTS OF 35 TO 50 MPH. THE BONG AND BLATNIK BRIDGES BETWEEN DULUTH AND SUPERIOR WERE SEEING EVEN HIGHER GUSTS OF 50 TO 60 MPH. THE ARROWHEAD AND IRON RANGE AREAS WERE PRIMARILY DRY DUE TO DRIER AIR FROM CANADA FILTERING INTO THE REGION. THERE HAD REPORTS THROUGH THE LATE MORNING AND EARLY AFTERNOON OF POWER OUTAGES AND DOWNED TREES ACROSS THE TWIN PORTS AREA. THE MAIN CONCERNS THROUGH TONIGHT ARE THE WINDS AND POTENTIAL FOR MIXED PCPN. LET US BEGIN WITH THE WINDS. IT APPEARS THE STRONG WINDS WILL CONTINUE THROUGH AT LEAST EARLY THIS EVENING. THE MODELS INDICATE THE WINDS OVER THE LAKE WILL GRADUALLY SHIFT TO THE NE THROUGH TONIGHT. THIS SHOULD SHIFT THE STRONGER WINDS AWAY FROM DULUTH AND TO THE SOUTH SHORE IN NW WISCONSIN. WE MIGHT NEED TO ISSUE A WIND ADVISORY FOR THE SOUTH SHORE COUNTIES THIS EVENING OR OVERNIGHT IF IT APPEARS THE WINDS WILL BE STRONG ENOUGH AT THAT TIME. THE MODELS SUGGEST THE RAIN OVER THE NORTHLAND WILL BEGIN TO FIZZLE OUT LATE THIS AFTERNOON AND THIS EVENING...BUT THAT A NARROW BAND OF LIGHT TO MODERATE PCPN COULD LINGER INTO EARLY THIS EVENING DUE TO SOME LOW TO MID LEVEL FRONTOGENESIS. THE HRRR/WRF/NAM ARE SHOWING THIS BANDS SOMEWHERE NEAR...OVER...OR SOUTH OF THE TWIN PORTS. ALSO...MORE DRIER AIR WILL BE WORKING INTO NORTHERN MINNESOTA...SO CHANCES OF PCPN WILL DECREASE ACROSS THE NW FORECAST AREA. THE MODELS INDICATE TEMPERATURES ALOFT WILL COOL INTO THIS EVENING...AND THERE WILL LIKELY BE A TRANSITION TO SNOW OVERNIGHT FOR AT LEAST MUCH OF NE MINNESOTA AND BORDER AREAS OF NW WISCONSIN. THERE COULD BE A SHORT PERIOD OF FREEZING RAIN NEAR THE TWIN PORTS AND CLOQUET AREAS THIS EVENING IF THE SURFACE TEMPERATURES ARE ABLE TO COOL QUICKLY ENOUGH BEFORE THE PCPN TRANSITIONS FROM RAIN TO SNOW. I HAVE LOW CONFIDENCE OF THIS OCCURRING...SO I DID NOT FORECAST ANY ICE ACCUMULATION AND HELD OFF ON ANOTHER FREEZING RAIN ADVISORY. THE EVENING SHIFT WILL NEED TO REEVALUATE THE SITUATION EARLY THIS EVENING. MUCH OF THE SNOW THAT WILL FALL TONIGHT WILL LIKELY MELT. HOWEVER...IF SURFACE TEMPERATURES ARE ABLE TO COOL MORE THAN THOUGHT...THEN THERE COULD BE MORE SIGNIFICANT SNOW ACCUMULATION. I FORECASTED ABOUT 1 TO 2 INCHES OF ACCUMULATION FOR THE TWIN PORTS / CLOQUET / MOOSE LAKES AREAS THROUGH TONIGHT. MUCH LESSER AMOUNTS ARE EXPECTED ELSEWHERE ACROSS THE NORTHLAND SINCE SURFACE TEMPERATURES WILL LIKELY STAY IN THE MID 30S MUCH LONGER THAN THE TWIN PORTS AREA...WHERE IT WILL COOL TO THE LOW 30S BY EARLY THIS EVENING. .LONG TERM...(TUESDAY THROUGH MONDAY) ISSUED AT 315 PM CDT MON APR 28 2014 GENERAL AGREEMENT THAT STACKED SFC/UPPER LOW WILL ROTATE A SHORTWAVE LOBE CYCLONICALLY INTO THE CWA TUESDAY. THIS ALLOWS A SURGE OF MOISTURE TRANSPORT TO OCCUR NEAR THE 85H LEVEL AND WORKS ITS WAY FROM THE SRN CWA INTO THE CTRL CWA AS THE DAY UNFOLDS. UNFORTUNATELY WE STILL HAVE PTYPE ISSUES AS THE USUAL CAST OF CHARACTERS...VERTICAL MOTION...ICE CRYSTAL INITIATION OR NOT...AND BOUNDARY LAYER TEMPS. WILL GO AHEAD AND GIVE IT THE BEST SHOT AND PUSH AN AREA OF MODERATE SNOW INTENSITY ACROSS NW WISC ZONES INTO THE TWIN PORTS BETWEEN 12Z/18Z. MAY SEE A FEW INCHES IN THAT TIME HOWEVER WITH SFC TEMPS NEAR AND ABOVE FREEZING ENOUGH MELTING AND COMPACTION MAY OCCUR TO REDUCE MUCH IN THE WAY OF ACCUMULATION. THE TIMING OF ADDITIONAL AREAS OF ENHANCED ASCENT ARE DIFFICULT BEYOND TOMORROW AFTERNOON. UNSETTLED WEATHER WILL REMAIN ACROSS THE CWA THROUGH THE WEEK. THE SYNOPTIC SCALE PATTERN FEATURES A BLOCKED MID LVL FLOW AT LEAST UNTIL THURSDAY...IF NOT LONGER. THE SFC LOW WILL CRAWL SLOWLY EAST INTO UPPER MICHIGAN BY THURSDAY. THE DEEP MOIST CYCLONIC CIRCULATION OVERHEAD SHOULD KEEP PRECIP IN THE AREA THROUGH LATE THURSDAY...ALTHOUGH IT MAY BE OCCASIONAL IN NATURE. MDL CONSENSUS QPF SUGGESTS AREAL AVERAGES OF ABOUT .25 TO .50 INCHES ARE POSSIBLE WED INTO FRIDAY. ALTHOUGH SPRING BLOCKS ARE NOTORIOUS FOR MAINTAINING THEIR INTEGRITY...LATEST NWP SOLUTIONS ARE UNANIMOUS THAT THE CLOSED CIRCULATION WILL BE EJECTED EASTWARD THIS WEEKEND AS THE UPPER JET INCREASES ACROSS SRN CANADA INTO THE NRN PLAINS. TEMPS REMAIN BELOW CLIMO THROUGH THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1227 AM CDT TUE APR 29 2014 AN AREA OF MVFR CONDITIONS WILL BE OVER THE SOUTHERN AREAS WITH SPOTTY SHOWERS OF SNOW...RAIN OR SLEET...WHILE NORTHERN AREAS OF KDLH...KHIB AND KINL WILL BE MAINLY VFR. CIGS AND VSBYS WILL GO BACK DOWN TO MVFR OR IFR LATER TODAY...MAINLY AFTER 12Z TO 18Z AS MORE ROBUST LIFT AND MOISTURE COME BACK TO TO THE REGION FOR MORE SNOW. && .PRELIMINARY POINT TEMPS/POPS... DLH 33 40 35 43 / 90 80 60 50 INL 34 45 37 45 / 80 80 60 50 BRD 35 44 37 46 / 80 80 60 40 HYR 34 45 36 46 / 90 80 60 60 ASX 34 40 35 43 / 90 80 60 60 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...GALE WARNING UNTIL 10 AM CDT THIS MORNING FOR LSZ140>147. SMALL CRAFT ADVISORY UNTIL 4 AM CDT WEDNESDAY FOR LSZ121-148. && $$ UPDATE...CLC SHORT TERM...GROCHOCINSKI LONG TERM...CANNON AVIATION...CLC/MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1123 PM CDT MON APR 28 2014 .SYNOPSIS... ISSUED AT 337 PM CDT MON APR 28 2014 H5 ANALYSIS FROM THIS MORNING HIGHLIGHTS A NEGATIVE TILTED UPPER LEVEL LOW OVER CENTRAL NEBRASKA WITH A DOWN STREAM RIDGE EXTENDING FROM THE UPPER OHIO VALLEY NWWD INTO THE HUDSON BAY OF CANADA. A STRONG JET STREAK EXTENDED FROM NRN CALIFORNIA...TO CENTRAL TX...CURVING NE INTO THE OZARKS AND LOWER OHIO VALLEY. WITHIN THIS FEATURE...A 90+KT JET MAX EXTENDED FROM SERN OK INTO FAR NERN ARKANSAS. WV IMAGERY AS OF MIDDAY HAS THE UPPER LOW NEAR BROKEN BOW NEBRASKA. AT THE SURFACE...STRONG LOW PRESSURE WAS LOCATED OVER NERN NEBRASKA A COLD FRONT EXTENDED EAST SOUTHEAST OF THE LOW INTO SOUTH CENTRAL IOWA...SOUTH INTO CENTRAL ARKANSAS. STRONG WINDS CONTINUES ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON AND WINDS HAVE GUSTED AS HIGH AS 58 MPH AT THEDFORD AND NORTH PLATTE. OCCASIONAL SHOWERS WERE OCCURRING ACROSS SOUTHWESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON WITH SOME EMBEDDED THUNDERSTORMS IN FAR NORTHEASTERN PORTIONS OF THE FORECAST AREA. TEMPERATURES AT 3 PM CDT RANGED FROM THE MIDDLE 30S TO MIDDLE 40S. && .UPDATE... ISSUED AT 844 PM CDT MON APR 28 2014 NEDOR CAMS AND THE RAP MODEL SUGGEST 1 TO 5 INCHES OF SNOW TONIGHT SPREADING AS FAR EAST AS BROWN AND KEYA PAHA COUNTIES. THE WINTER WEATHER ADVISORY HAS BEEN EXPANDED EAST INTO THE THESE AREAS. WINDS APPEAR TO HAVE DIMINISHED BELOW HIGH WIND CRITERIA SO THE HIGH WIND WARNING HAS BEEN CANCELLED. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 337 PM CDT MON APR 28 2014 CLOSED LOW CONTINUES TO DRIFT SLOWLY ACROSS THE CENTRAL PLAINS. SEVERAL HAZARDS TO CONTENT WITH TONIGHT AND TOMORROW...INCLUDING STRONG WINDS...RAIN AND SNOW. THE SFC LOW MOVES ACROSS THE MISSOURI RIVER TONIGHT...MEANWHILE A HIGH PRESSURE BUILDS ACROSS THE NORTHERN ROCKIES. THIS WILL CREATE A TIGHT PRESSURE GRADIENT AND STRONG WINDS EXPECTED TO CONTINUE. MODELS IN GOOD AGREEMENT BY INCREASING 850 MB WINDS OVERNIGHT TO 60 KTS OVER SW NEB. WILL EXTEND THE HIGH WIND TO ACCOUNT FOR DAYTIME MIXING AND POTENTIAL FOR VERY STRONG WINDS. THEN OVERNIGHT EXPECT SLIGHTLY LESS MIXING AND A HIGH END WIND ADVISORY...HOWEVER WILL CONTINUE TO MONITOR CLOSELY. SO FAR TODAY THE SHOWERS HAVE HELP TO LIMIT THE MIXING AND EXPECT THE NEXT DEFORMATION BAND TO DEVELOP AND BRING ADDITIONAL PRECIPITATION AND LIMIT MIXING THE VERY STRONG WINDS TO THE SFC. NOW PRECIP IS AN ISSUE. 850 MB TEMPS BELOW ZERO ARE SPREADING INTO PORTIONS OF NW NEB EARLY TONIGHT IN THE NAM/EC/GEM...HOWEVER THE GFS IS A LITTLE SLOWER. THIS IS CRITICAL AS LIKE LAST NIGHT...NW NEB SHOULD SEE ENOUGH COLD AIR RETURN FOR SNOW. MODELS BRING MORE OF THE COLD AIR INTO CHERRY COUNTY...WHICH MAKES SENSE AS THE LOW IS A LITTLE FURTHER TO THE SE...AND EXPECT TO SEE SOME SNOW ACROSS SHERIDAN AND CHERRY COUNTY. A MIX OR A CHANGE TO ALL SNOW IS POSSIBLE FURTHER SOUTH AND EAST...AND THIS WILL NEED TO BE MONITORED. WILL ISSUE A WINTER WX ADVISORY FOR SHERIDAN AND CHERRY AS THE SNOW SHOULD PILE UP TO A FEW INCHES...AND CANNOT RULE OUT AROUND 6 NEAR THE BORDER. TOMORROW TEMPS WARM A LITTLE IN THE MORNING AND A CHANGE TO ALL LIQUID IS EXPECTED. MODELS BRING MORE DRY AIR INTO THE SYSTEM WHICH WRAPS ESPECIALLY INTO SW NEB. DID LOWER POPS AND COULD EASILY SEE LITTLE IF ANY PRECIP OVER THE SOUTHERN SANDHILLS AND SOUTHWEST NEB FOR THE AFTERNOON. MEANWHILE WINDS CONTINUE TO BE STRONG AND WILL CONTINUE THE WIND ADVISORY...CONVERTING THE WINTER WX TO A WIND ADVISORY AS THE SNOW IS EXPECTED TO END. THE BIG CONCERN HERE IS THE POTENTIAL FOR HIGH WIND CRITERIA IF WE SEE SOME BREAKS IN THE SKY. THIS WILL ALLOW FOR WARMER TEMPS AND BETTER MIXING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 337 PM CDT MON APR 28 2014 TUESDAY NIGHT THROUGH THURSDAY...WINDS AND PRECIPITATION CHANCES WILL BE THE MAIN FORECASTING CONCERNS FOR THE MIDDLE OF THIS WEEK. FOR TUESDAY NIGHT...THE LATEST MET/MAV GUIDANCE IS INDICATIVE OF BREEZY CONDITIONS CONTINUING INTO THE OVERNIGHT TUESDAY NIGHT. THIS WILL KEEP TEMPS FROM CRASHING INTO THE 20S. THERE IS SOME DISCREPANCIES BTW THE NAM AND GFS SOLNS WITH THEIR DEPICTION OF H85 TEMPS BY 12Z WEDNESDAY WITH THE GFS BEING 2 TO 4C COOLER COMPARED TO THE NAM SOLN. GIVEN THE DISCREPANCIES...DECIDED TO BLEND THE MAV AND MET GUIDANCE FOR LOWS TUESDAY NIGHT. THIS LED TO LOWS AROUND 30 IN THE WEST...TO 35 IN THE EAST. AS FOR PCPN CHANCES...THE LATEST MODELS PUSH A NICE PLUME OF DRY AIR INTO THE FORECAST AREA FROM NORTH TO SOUTH TUESDAY NIGHT. WE WILL STILL SEE SOME LOW CLOUDINESS ACROSS THE FORECAST AREA...HOWEVER...WITH MUCH DRIER AIR MOVING IN ABOVE 6000 FT AGL...DO NOT SEE MUCH OF A THREAT FOR PCPN ANYMORE AND HAVE ELIMINATED IT FROM THE FCST FOR OVERNIGHT TUESDAY NIGHT INTO WEDNESDAY MORNING. ON WEDNESDAY...THE UPPER LEVEL LOW WILL RETROGRADE NORTHWEST INTO CENTRAL AND SRN MINNESOTA. A NICE VORT LOBE WILL ROTATE AROUND THE WESTERN AND SOUTHWESTERN PERIPHERY OF THE LOW...AND WILL INCREASE THE THREAT FOR PCPN IN THE NORTHEASTERN CWA WEDS AFTERNOON/WEDS EVENING. ATTM...THE LATEST NAM AND GFS SOLNS ARE INDICATING SOME WEAK ISENTROPIC LIFT AT THE 295K LEVEL AND LOW COND PRESSURE DEFICITS IN THE EASTERN HALF OF THE FORECAST AREA DURING THE WEDS AFTN/EVE PERIOD. WINDS WILL BE GUSTY WEDNESDAY ONCE AGAIN...ESPECIALLY ACROSS THE WEST AND SOUTHWEST WHERE SOME CLEARING IS POSSIBLE...STEEP LAPSE RATES WILL FACILITATE GOOD MIXING. WITH H85 WINDS AROUND 35 KTS WEDS AFTN...ANOTHER WINDY DAY IS ON TAP ACROSS THE FORECAST AREA...AND MAY FACILITATE ISSUANCE OF YET ANOTHER WIND ADVISORY WEDNESDAY AFTERNOON INTO EARLY WEDS EVENING. BY THURSDAY...THE UPPER LEVEL LOW WILL FINALLY CLEAR THE MIDDLE AND UPPER MISSISSIPPI VALLEYS. THIS WILL LEAD TO LIGHTER WINDS THURSDAY AND WARMER TEMPS WITH READINGS REACHING THE LOWER TO MIDDLE 50S. FRIDAY TO MONDAY...THE UPPER LEVEL LOW WILL BE ABSORBED BY THE NORTHERN STREAM...BEING ABSORBED BY A QUASI STATIONARY LOW OVER CENTRAL CANADA. THIS WILL PLACE THE CENTRAL AND NORTHERN PLAINS IN A ZONAL FLOW PATTERN THIS WEEKEND INTO EARLY NEXT WEEK. TEMPERATURES WILL BE FAIRLY SEASONAL THIS WEEKEND WITH HIGHS GENERALLY IN THE 60S. MAINLY DRY CONDS ARE EXPECTED WITH THE EXCEPTION OF SATURDAY AND SATURDAY NIGHT. A MID LEVEL FRONTO BOUNDARY WILL BE DRAPED ACROSS THE NORTHERN FORECAST AREA AND SOUTH DAKOTA SATURDAY INTO SATURDAY NIGHT. AT THE SAME TIME...A NORTHERN STREAM WAVE WILL LIFT ACROSS THE NRN TIER OF STATES. ENHANCED LIFT WILL BE PRESENT ACROSS NRN NEBRASKA SATURDAY AND SATURDAY NIGHT...AND HAVE INSERTED SOME LOW POPS INTO THE FCST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1123 PM CDT MON APR 28 2014 MVFR IN RAIN AND LOW CIGS ANDLOCAL IFR/LIFR IN SNOW CONTINUE TONIGHT AND IMPROVE TO VFR/MVFR BETWEEN 15Z-18Z TUESDAY. IT IS DIFFICULT TO FORECAST WHEN ALL AREAS WILL BE VFR TUESDAY EVENING GIVEN THE AMOUNT OF TRAPPED MOISTURE BELOW 3000 FEET AGL. THERE ARE INDICATIONS THAT VFR COULD BECOME WIDESPREAD ALONG AND WEST OF HIGHWAY 83 BY 00Z TUESDAY EVENING. && .LBF WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ TUESDAY FOR NEZ004-005- 007-009-010-022>029-035>038-056>059-069>071-094. WINTER WEATHER ADVISORY UNTIL 10 AM CDT /9 AM MDT/ TUESDAY FOR NEZ004>006-008-094. WIND ADVISORY FROM 10 AM TO 7 PM CDT TUESDAY FOR NEZ006-008. && $$ UPDATE...CDC SYNOPSIS...CLB SHORT TERM...MASEK LONG TERM...CLB AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
113 AM CDT TUE APR 29 2014 .UPDATE... ISSUED AT 113 AM CDT TUE APR 29 2014 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. FOLLOWED CLOSELY TO THE 04 UTC HRRR FOR POPS AND PRECIPITATION TYPE TONIGHT INTO TUESDAY MORNING BASED UPON THE SUPERIOR VERIFICATION OF THE HRRR THROUGHOUT THIS STORM. PREDOMINATELY SNOW WILL CONTINUE WEST...TRANSITIONING TO MOSTLY RAIN ACROSS THE JAMES RIVER VALLEY WHERE LOW LEVEL WARM AIR ADVECTION SHOULD HOLD SURFACE TEMPERATURES IN THE 36-38 F RANGE MUCH OF THE NIGHT. UPDATE ISSUED AT 944 PM CDT MON APR 28 2014 CONTINUING TO SEE TEMPS A LITTLE WARMER THAN FORECAST ACROSS EASTERN CWA INCLUDING JAMES RIVER VALLEY...RESULTING IN MAINLY RAIN THIS EVENING. OTHERWISE CONTINUING TO SEE LIGHT SNOW WEST AND A MIX CENTRAL. MAIN CHANGES WITH UPDATE WERE TO INCREASE TEMPS EAST AND KEEP A MIX OF PRECIP THERE LONGER. AREA OF SLIGHTLY STRONGER REFLECTIVITIES CURRENTLY MOVING INTO FAR SOUTHEAST CWA WITH A SLOW EXPANSION OF WEAK REFLECTIVITIES TOWARD THE UPPER JAMES RIVER VALLEY FARTHER NORTH. UPDATE ISSUED AT 701 PM CDT MON APR 28 2014 MINOR ADJUSTMENTS MADE TO PRECIP TYPE AND TEMPS...MAINLY ACROSS THE EASTERN CWA. REFLECTIVITIES HAVE DIMINISHED IN GENERAL...BUT CONTINUE TO SEE A HIGH POP/LOW QPF EVENT THROUGH THE NIGHT. FARTHER EAST...INCLUDING JAMESTOWN...LIGHT RAIN CONTINUES WITH RADAR SHOWING WEAK RETURNS AT BEST IN THAT AREA. OTHERWISE...BAND OF PRECIP HAS CONTINUED TO PUSH INTO FAR WESTERN ND WITH KISN RECENTLY REPORTING LIGHT RAIN AND KDIK REPORTING LIGHT SNOW WITH THE LAST OB. RUC/HRRR CONTINUE TO SUPPORT ONGOING LIGHT PRECIP THROUGH THE NIGHT WITH AREAS ACROSS THE EAST EXPECTED TO FILL IN THIS EVENING. FOR TOMORROW...MODELS LOOK TO BE IN GOOD AGREEMENT WITH DRYER AIR PUNCHING IN FROM NORTHEAST TO SOUTHWEST DURING THE DAY...BRINGING AN END TO PRECIP. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 352 PM CDT MON APR 28 2014 FORECAST CHALLENGE WILL BE THE RAIN/SNOW DEMARCATION TONIGHT. WITH TEMPERATURES IN THE MID 30S MANY AREAS THERE IS A FINE LINE BETWEEN RAIN AND SNOW THIS AFTERNOON. RAIN HAS CHANGED TO SNOW FROM HARVEY AND DENHOFF TO JAMESTOWN. SOUTH CENTRAL...AROUND BISMARCK/MANDAN TEMPERATURES ARE WARM ENOUGH FOR RAIN THROUGH THE AFTERNOON AND ACROSS THE WEST IT WAS COOL ENOUGH FOR LIGHT SNOW. TEMPS WILL LIKELY FALL TO THE MID 30S BY EARLY EVENING SOUTH CENTRAL AND SNOW WILL SPREAD INTO THE SOUTH CENTRAL. MODELS FORECAST ENOUGH QPF FOR 1 TO 2 INCHES OF SNOW ACROSS THE REGION ON TUESDAY DRYING AIR FROM THE NORTHEAST WILL BRING AN END TOP THE PRECIPITATION WITH COOL TEMPERATURES AGAIN. HIGHS WILL LIKELY REMAIN IN THE UPPER 30S TO AROUND 40 WEST TO THE LOWER 40S CENTRAL. WILL HANDLE THIS WITH AN SPECIAL WEATHER STATEMENT FOR 1 TO 2 INCHES OF SNOW WITH AN ISOLATED 3 INCH AMOUNT NOT OUT OF THE REALM OF POSSIBILITY IN THE JAMES RIVER VALLEY. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 352 PM CDT MON APR 28 2014 AN ACTIVE AND COOL WEATHER PATTERN FOR THE LONG TERM PERIOD. LARGE UPPER LEVEL LOW PRESSURE CENTERED OVER THE WESTERN GREAT LAKES/UPPER MISSISSIPPI VALLEY REGION WILL CONTINUE TO SPIN THROUGH WEDNESDAY NIGHT...THEN WILL FINALLY LIFT NORTHEAST THURSDAY INTO FRIDAY INTO SOUTHEASTERN CANADA. FOR THE NORTHERN PLAINS...CYCLONIC FLOW ALOFT WILL TRANSITION TO A NORTHWESTERLY FLOW ALOFT THURSDAY ONCE THE LOW LIFTS OUT...THEN QUASI-ZONAL LATE IN THE WEEKEND INTO THE EARLY PORTIONS OF THE FOLLOWING WORK WEEK. DRY AIR WILL SPREAD FROM NORTH TO SOUTH TUESDAY NIGHT ENDING MOST IF NOT ALL PRECIPITATION ACROSS WEST AND CENTRAL NORTH DAKOTA. INCREASING CHANCES FOR RAIN OR SNOW EAST OF HIGHWAY 83 ON WEDNESDAY AS THE UPPER LOW WOBBLES/RETROGRADES SLIGHTLY WEST..ALLOWING FOR ONE OF ITS SPIRAL ARMS OF MOISTURE TO ROTATE THROUGH THE EASTERN DAKOTAS. CHANCES FOR PRECIPITATION ACROSS EASTERN NORTH DAKOTA DECREASE WEDNESDAY NIGHT INTO THURSDAY AS THE UPPER LOW ONCE AGAIN MOVES FARTHER EAST. PRECIPITATION AMOUNTS WEDNESDAY MORNING THROUGH WEDNESDAY EVENING WILL BE MINIMAL SO ANY SNOW AMOUNTS WILL ALSO BE MINIMAL...WITH UP TO A HALF AN INCH OF SNOW FROM THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY. DRY CONDITIONS OVERNIGHT WEDNESDAY THROUGH THURSDAY MORNING AS A SUBTLE S/WV RIDGE PASSES THROUGH THE AREA. AS OUR FLOW ALOFT BECOMES MORE NORTHWEST...SEVERAL EMBEDDED WAVES WILL TRACK FROM NORTHWEST TO SOUTHEAST THROUGH THE NORTHERN PLAINS LATER IN THE DAY THURSDAY...THROUGH THURSDAY NIGHT...AND INTO FRIDAY...EACH GENERATING A CHANCE OF RAIN OR SNOW (DEPENDING ON THE THERMAL PROFILE AND SFC TEMPERATURES). FURTHER OUT IN TIME...OVER THE WEEKEND...THERE STILL EXISTS LOTS OF UNCERTAINTY. THE 12Z ECMWF DROPS A STRONG MID LEVEL S/WV TROUGH/SFC COLD FRONT THROUGH THE REGION SATURDAY...WHILE THE GFS KEEPS THIS FEATURE OFF TO OUR NORTH AND EAST. BOTH MAINTAIN WELL BELOW AVERAGE TEMPERATURES AND SOME SORT OF PRECIPITATION CHANCES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 113 AM CDT TUE APR 29 2014 WIDESPREAD IFR CONDITIONS IN SNOW...RAIN AND STRATUS WILL CONTINUE ACROSS WESTERN AND CENTRAL NORTH DAKOTA TONIGHT INTO TUESDAY MORNING. PRECIPITATION WILL END AND STRATUS LIFT FROM NORTHEAST TO SOUTHWEST LATE TUESDAY MORNING AND THROUGH THE AFTERNOON. STRONG NORTHERLY WINDS WITH GUSTS OF 25-30 KTS ARE EXPECTED FOR ALL TERMINALS ON TUESDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...WAA LONG TERM...NH AVIATION...AYD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1133 PM CDT MON APR 28 2014 .AVIATION 06Z DISCUSSION... CONVECTION ON THE DECREASE CURRENTLY. BY 09Z...MOST OF THE PRECIPITATION WILL BE OUT OF THE AREA. SOME LIGHT FOG WILL THEN BE POSSIBLE BUT CIGS SHOULD NOT BE TOO LOW THROUGH 12Z. DURING THE DAY ON TUESDAY...THE ATMOSPHERE WILL RECHARGE ONCE AGAIN WITH THUNDERSTORMS POSSIBLE MAINLY AFTER 18Z. SOME OF THESE STORMS COULD BE STRONG AND MAYBE EVEN SEVERE. SOME SHOWER AND TSTM ACTIVITY WILL PERSIST BEYOND 00Z...ESPECIALLY ACROSS EASTERN MID TN. && .PREV DISCUSSION... /ISSUED 1023 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... OHX VWP IS NOW SHOWING SOME VEERING OF THE WIND FIELD WITH TIME IN THE LOWER LEVELS. THUS...THE DRIER AIR IS ON THE WAY. THIS IS FURTHER SUPPORTED BY A CONTINUING DECREASE IN COVERAGE OVER THE AREA. WILL GO AHEAD AND CONTINUE TO LOWER POPS GRADUALLY WITH TIME. OTW...STILL NO IMMEDIATE THREAT ACROSS THE TOR WATCH AREA. ACTIVITY OVER NRN AL IS HAVING A DIFFICULT TIME MAINTAINING ANY STRENGTH. STILL...A LITTLE TOO EARLY TO CANCEL THE WATCH SO WILL LET IT RIDE FOR NOW. FOR THE UPDATE...AGAIN WILL LOWER POPS. PREV DISCUSSION... /ISSUED 957 PM CDT MON APR 28 2014/ UPDATE... COVERAGE OVER THE MID STATE HAS DECREASED SOME AND IS MORE BROKEN IN NATURE NOW. INSTABILITY PARAMETERS CONTINUE TO LOOK RATHER WEAK ACROSS WESTERN MIDDLE ALTHOUGH 850 MB WIND IS STILL REASONABLY STRONG. STILL HOWEVER...THE BACK EDGE OF THE PRECIP HAS NOT MADE MUCH OF AN ADVANCEMENT EASTWARD YET. FURTHER EAST...CURRENTLY THE TOR WATCH AREA IS NOT UNDER AN IMMEDIATE THREAT. HOWEVER...WE DO SEE SOME STORM REDEVELOPMENT OVER NW AL AT THIS TIME AND HELICITY VALUES OVER THE WATCH AREA REMAIN ELEVATED. THEREFORE...WILL ELECT TO KEEP THE WATCH GOING FOR NOW. MAY BEGIN TO TAPER POPS ACROSS OUR WEST IN AN HOUR OR TWO...DEPENDING ON FUTURE TRENDS. OTW...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 816 PM CDT MON APR 28 2014/ AVIATION 00Z DISCUSSION... SEVERE WEATHER REMAINS A POSSIBILITY FOR THE CSV AREA. SHOWERS AND TSTMS WILL CONTINUE ACROSS MAINLY THE CSV AND BNA AREAS THROUGH AT LEAST 06Z. SOME OF THE STORMS COULD REACH STRONG OR SEVERE LIMITS NEAR CSV BETWEEN NOW AND 06Z. PRECIP SHOULD END BY 09Z FOR CSV WITH A BREAK UNTIL 18Z ON TUESDAY WHEN TSTMS MAY FIRE UP AGAIN. PREV DISCUSSION... /ISSUED 812 PM CDT MON APR 28 2014/ UPDATE... STRONG TO POTENTIALLY SEVERE TSTMS MARCHING NE ACROSS THE SOUTHERN PLATEAU. LAPS STILL SHOWING AN IMPRESSIVE SLUG OF AMPLIFIED HELICITY ACROSS THIS REGION. ALTHOUGH THE HELICITY STRENGTH IS ON THE DOWN SLIDE. TOR WATCH NUMBER 111 WILL BE ALLOWED TO CONTINUE FOR NOW FOR THOSE 6 COUNTIES IN OUR EAST AND SOUTHEAST. OTW...BACK EDGE OF THE SHOWER AND TSTM ACTIVITY EXTENDS FROM CLARKSVILLE SW THROUGH LOBELVILLE. NO EASTWARD PUSH IS INDICATED AND A SLIGHT WESTWARD PUSH IS INDICATED. MODELS STILL IN AGREEMENT WITH DRIER AIR WINNING OUT LATER TONIGHT. AT SOME POINT OVER THE NEXT FEW HOURS...SHOULD BEGIN TO SEE AN EASTWARD PUSH WITH THE PRECIP SLOWLY ENDING FROM WEST TO EAST. INSTABILITY PARAMETERS CONTINUE TO LOOK TOO WEAK TO SUPPORT SEVERE DEVELOPMENT. BUT...PERHAPS A STRONG STORM OR TWO COULD STILL DEVELOP OVER OUR SOUTHERN COUNTIES OVER THE NEXT HOUR OR TWO. FOR THE FORECAST...NO CHANGES FOR NOW. PREV DISCUSSION... /ISSUED 514 PM CDT MON APR 28 2014/ MESOSCALE UPDATE... LATEST LAPS DATA CLEARLY SHOWS THAT THE BETTER INSTABILITY IS OVER OUR SOUTHERN AREAS WHICH IS WHERE THE TOR WATCH IS IN EFFECT. CAPE VALUES...SHOWALTERS ALL IN SUPPORT OF THE SUBSTANTIAL AMOUNTS OF INSTABILITY ACROSS THE SOUTH. CURRENT RADAR SHOWS THE STRONGEST ACTIVITY FROM DICKSON COUNTY SOUTHWARD THROUGH GILES COUNTY WITH AGAIN...THE STRONGEST ACTIVITY THE FURTHER SOUTH YOU GO. WE DO SEE A LINE OF THUNDERSTORMS ATTEMPTING TO DEVELOP BACK ACROSS WESTERN KY. HOWEVER...THERE IS A DEGREE OF INCREASING CAP STRENGTH ACROSS OUR NORTHERN AREAS. THUS...IT MAY HAVE A TOUGH TIME DEVELOPING INTO SOMETHING MORE SUBSTANTIAL. HRRR FURTHER CONCURS WITH THE IDEA OF NO REDEVELOPMENT TONIGHT TO THE WEST OF THE AFOREMENTIONED STRONGEST CONVECTION. BIGGEST POTENTIAL IMPACT OVER THE NEXT FEW HOURS WILL BE OVER OUR SOUTHERN AREAS WHERE THE POTENTIALLY TORNADIC CELLS COULD CLIP OUR FAR SOUTHERN COUNTIES AND EVENTUALLY OUR SOUTHERN PLATEAU. AS FOR THE FLOOD THREAT...THE FLASH FLOOD WATCH CONTINUES THROUGH TUESDAY EVENING. PREV DISCUSSION... /ISSUED 256 PM CDT MON APR 28 2014/ DISCUSSION... SIGNIFICANT SEVERE WEATHER THREAT STILL EXISTS OVER FAR SOUTHERN MIDDLE TN THROUGH TONIGHT... A STRONG LOW PRESSURE CENTER OVER EASTERN NEBRASKA WILL DRAG A COLD FRONT THROUGH THE REGION LATE TONIGHT...WITH ITS UPPER LOW LAGGING AND SPINNING ACROSS THE UPPER MIDWEST. STRONG DIVERGENCE ALOFT ON THE NOSE OF A 115-KT UPPER JET HAS LED TO AMPLE PRECIP ACROSS MIDDLE TN THIS MORNING THROUGH THE EARLY AFTERNOON HOURS. THIS ACTIVITY HAS LED TO 3-5 INCH RAINFALL AMOUNTS MAINLY WEST OF I-65 AND SOUTH OF I-40...WHERE RESIDUAL FLOODING AND FLASH FLOODING CONTINUE. A FLASH FLOOD WATCH CONTINUES FOR ALL OF MIDDLE TN AND WILL BE EXTENDED THROUGH TUESDAY AFTERNOON GIVEN THE RIVER FLOODING THREAT FROM ADDITIONAL RAINS FROM THIS EVENING THROUGH THE OVERNIGHT HOURS. WILL ISSUE THE UPDATED FLASH FLOOD WATCH SOON. MORE INTERESTINGLY...THE MORNING CONVECTION DROPPED AN OUTFLOW BOUNDARY ACROSS FAR SOUTHERN MIDDLE TN...WHERE POINTS NORTH OF THAT BOUNDARY REMAIN IN THE COLD POOL REGION...AND POINTS ALONG AND SOUTH OF THIS BOUNDARY REMAIN VERY UNSTABLE. THIS BOUNDARY EVEN CURLS BACK TO THE WEST A BIT OVER OUR FAR EASTERN CWA. WITH SFC CAPE VALUES AROUND 2000 J/KG AND AMPLE LOW-LEVEL SHEAR AS WELL AS DEEP LAYER SHEAR SOUTH OF THIS BOUNDARY...SPC ISSUED A PDS TORNADO WATCH FOR MAINLY OUR SOUTHERN TWO TIERS OF COUNTIES UNTIL 9PM. ANYTHING CLOSEST TO THE HUNTSVILLE COUNTY WARNING AREA WILL HAVE THE BEST CHANCE SEEING A SIGNIFICANT THREAT FOR SUPERCELLS...WHICH MEANS A TORNADO...HAIL AND DAMAGING WIND THREAT. TORNADOES ON THE GROUND HAVE BEEN REPORTED IN NORTHERN MS ALREADY...MOVING NE. IT WILL BE A CLOSE CALL FOR FAR SOUTHERN MIDDLE TN. FYI...WE WILL ADD GRUNDY COUNTY TO THE WATCH AS WELL. ALSO...NORTH OF THIS BOUNDARY...SEVERE STORMS WILL STILL BE POSSIBLE BUT HAIL WILL BE THE ONLY SEVERE WEATHER THREAT FOR STORMS IN THE COLD POOL. SUPERCELLS OVER MS SHOULD COAGULATE INTO A LARGE AREA OF CONVECTION AND THIS SHOULD SPREAD NORTHWARD WITH TIME. OVERNIGHT...THIS WILL MOVE EAST THROUGH MIDDLE TN...AND POPS COULD TAPER FROM WEST TO EAST TOWARDS TUESDAY MORNING. AN ADDITIONAL 1-2 INCHES OF RAINFALL WILL BE POSSIBLE THROUGH TONIGHT...WITH LOWS AROUND 60. ON TUESDAY...THE SFC LOW SHOULD ROTATE A LITTLE FURTHER EAST AND ANOTHER LOBE OF ENERGY FROM THE UPPER LOW WILL SWING THROUGH THE REGION. WOULD THINK ANOTHER ROUND OF AFTERNOON-EVENING CONVECTION SHOULD EASILY BE GENERATED...THIS TIME WITH MORE SHEAR ACROSS MIDDLE TN...MORE SUNSHINE THROUGH THE MORNING HOURS...AND COLDER AIR ALOFT WITH THE UPPER LOW GETTING CLOSER. WOULD EXPECT ANOTHER ROUND OF SEVERE WEATHER TOMORROW AFTERNOON AND EVENING...WITH LARGE HAIL AND DAMAGING WINDS THE BEST THREAT. EVEN AN ISOLATED TORNADO OR TWO CAN NOT BE RULED OUT. FINALLY THE SYSTEM WILL MOSTLY PULL OUT ON WEDNESDAY...WITH PERHAPS SOME LINGERING SHOWERS INTO WEDNESDAY EVENING. TEMPS WILL COOL OFF INTO THE 70S ON WEDNESDAY...AND EVEN COOLER THURSDAY- SATURDAY IN THE 60S. CONDITIONS SHOULD MOSTLY BE DRY THURSDAY ON...WITH TEMPS WARMING BACK UP TO NEAR 80 SUNDAY AND MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR TNZ005>011-023>034- 056>066-075-077>080-093>095. && $$ 21
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
423 AM CDT TUE APR 29 2014 .SHORT TERM (TODAY THROUGH WEDNESDAY)...MARINE LAYER WITH LOW STRATUS AND FOG HAS MOVED INTO THE COASTAL PLAINS EARLY THIS MORNING. A TROUGH AXIS AHEAD OF THE FRONT...OVER THE HILL COUNTRY EARLY THIS MORNING...WILL MOVE TOWARD THE COAST BY 15Z WITH THE FRONT MOVING IN LATER THIS MORNING. HIGHER NORTH WINDS BEHIND FRONT SINCE IT IS HARD TO SAY COLD FRONT WHEN THE TEMPERATURES ARE STILL EXPECTED TO REACH THE 90S TODAY. WENT WITH HRRR MODEL DEPICTING MUCH LOWER DEWPOINT TEMPS REACHING THE COASTAL PLAINS THIS AFTERNOON. COOLER AND DRIER AIR WILL REACH AREA FOR TONIGHT WITH LOWS MAINLY IN THE 50S. READINGS WILL FINALLY BE CLOSER TO NORMAL FOR WEDNESDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE AREA. && .MARINE (TODAY THROUGH WEDNESDAY)...WIDESPREAD FOG HAS MOVED INTO THE NORTHWEST GULF EARLY THIS MORNING. THIS FOG IS MIXED WITH SMOKE FROM CENTRAL AMERICA/YUCATAN PENINSULA AND VISIBILITIES ARE VERY POOR OVER THE WATERS. ISSUED DENSE FOG ADVISORY EARLIER AND KEPT EXPIRATION TIME AT 14Z. EXPECTING WINDS TO SHIFT TO SOUTHWEST WITH VISIBILITIES SLOWLY IMPROVING BEFORE MAIN FRONTAL WIND SHIFT MOVES INTO THE WATERS BY 18Z. WINDS WILL SLOWLY INCREASE AND SHOULD AT LEAST BE SCEC LEVELS FOR TONIGHT...BUT COULD BE LOW END SCA OVER THE OFFSHORE WATERS. WINDS WILL SUBSIDE AND TURN MORE TO THE NORTHEAST FOR WEDNESDAY. && .FIRE WEATHER (TODAY)...WITH GUSTY NORTH WINDS AND VERY DRY AIR MOVING INTO THE AREA FOR THIS AFTERNOON...ELEVATED FIRE DANGER THREAT WILL EXIST OVER THE BRUSH COUNTRY AND INLAND COASTAL PLAINS. MINIMUM RH LEVELS COULD FALL TO AROUND 10 PERCENT THIS AFTERNOON. && .LONG TERM (WEDNESDAY NIGHT THROUGH TUESDAY)...MILD TEMPERATURES WILL CONTINUE THROUGH THE REST OF THE WORK WEEK AS AN UPPER LVL LOW CONTINUES TO BE CENTERED OVER THE NORTHERN CENTRAL STATES. SURFACE TO LOW LVLS OF THE ATMOSPHERE REMAINS RATHER DRY...THOUGH PACIFIC MOISTURE PLUME BEGINS WORKING INTO THE UPPER LVLS DURING THE END OF THE WEEK. THIS WILL LEAD INCREASED CLOUD COVER ACROSS MUCH OF THE REGION MIDWEEK. BY FRIDAY UPPER LVL LOW FINALLY OPENS AND TROUGH SWINGS THROUGH TO THE EAST. RIDGING WILL THEN OCCUR OVER THE WEEKEND...AND TEMPERATURES WILL WARM BACK UP AS ONSHORE FLOW RETURNS AND MOISTURE INCREASES IN THE LOWER LEVELS. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 94 57 83 56 78 / 10 10 10 10 10 VICTORIA 89 52 80 50 78 / 10 10 10 10 10 LAREDO 97 60 87 58 81 / 10 10 10 10 10 ALICE 94 55 84 53 79 / 10 10 10 10 10 ROCKPORT 88 59 80 59 76 / 10 10 10 10 10 COTULLA 93 52 85 52 79 / 10 10 10 10 10 KINGSVILLE 95 55 84 55 77 / 10 10 10 10 10 NAVY CORPUS 86 62 79 63 76 / 10 10 10 10 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS... BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR... COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM... COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. && $$ TMT/89...SHORT TERM LK/84...LONG TERM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1156 PM CDT MON APR 28 2014 .DISCUSSION... 06Z TAF DISCUSSION. && .AVIATION... BOUNDARY CONTINUES TO MOVE NORTH JUST PASSING KIAH AND SAW DEWPOINT JUMP NEARLY 21 DEGREES. WITH LIGHT WINDS COULD GET MORE FOG THAN STRATUS SOUTH OF THE BOUNDARY. ADJUSTED SOME OF THE TAFS IN THAT TREND BUT MAY NEED MORE AMMENDMENTS. STRONGER FRONTAL PUSH STILL ON TRACK FOR TOMORROW AND SEE CIGS IMPROVE. WINDS STILL GUSTY IN THE AFTERNOON. 39 && .PREV DISCUSSION... /ISSUED 741 PM CDT MON APR 28 2014/ DISCUSSION... THE DRY LINE/COLD FRONT HAS REVERSED AND WAS MOVING INLAND AT 730 PM. DEWPOINTS ON THE NORTHWEST SIDE OF THE BOUNDARY WERE IN THE MID 30S...WHILE TO ITS SOUTHEAST THE DEWPOINTS WERE IN THE LOWER 70S. A DRASTIC CHANGE IN THE HUMIDITY LEVELS CAN BE FELT WHEREVER THE BOUNDARY CROSSES. THE LATEST RAP LOOKS TO HAVE A GOOD HANDLE ON THE MOVEMENT OF THE BOUNDARY THROUGH TONIGHT AND TUESDAY MORNING. STILL THINK PATCHY FOG IS POSSIBLE LATER TONIGHT ON THE SOUTHERN SIDE OF THE FRONT. FORECAST UPDATE MAINLY TO TWEAK THE DEWPOINT AND HUMIDITY GRIDS. 40 PREV DISCUSSION... /ISSUED 631 PM CDT MON APR 28 2014/ DISCUSSION... 00Z TAF DISCUSSION IN AVIATION SECTION. AVIATION... SFC ANALYSIS/RADAR IMAGERY AND EVEN VIS SATELLITE IMAGERY SHOW A DRY LINE PUSHING BACK NORTH WITH VERY MOIST BOUNDARY LAYER SOUTH OF THE BOUNDARY AND DRY NORTH. BOUNDARY SHOULD PUSH BACK NORTH AND SHOULD SEE A RAPID RISE IN SFC MOISTURE AS IT DOES. MAY GET SOME LOW STRATUS OR EVEN SOME PATCHY FOG TO DEVELOP AS A RESULT. DO NOT THINK THERE WILL BE VERY MUCH IN THE WAY OF MVFR CIGS AS THERE MAY BE ENOUGH MIXING OVERNIGHT. STRONGER FRONTAL PUSH IS EXPECTED TOMORROW MORNING WITH MAINLY NW WINDS IN THE AFTERNOON WHICH COULD BE GUSTY. SHOULD ALLOW FOR VFR CIGS ON WEDNESDAY. 39 PREV DISCUSSION... /ISSUED 347 PM CDT MON APR 28 2014/ DISCUSSION... VERY WARM ACROSS SOUTHEAST TEXAS THIS AFTERNOON AS SKIES HAVE CLEARED AND THE DRY LINE HAS MADE IT THROUGH THE CITY OF HOUSTON. THE DRY LINE IS EXPECTED TO RETREAT THIS EVENING AS IT SLOWLY WEAKENS WHICH WILL ALLOW MOISTURE TO WORK ITS WAY BACK INLAND. MOST LIKELY IT SHOULD STALL OUT AROUND A BRENHAM TO CONROE TO LIVINGSTON LINE. WITH THE MOISTURE RETURN PATCHY FOG WILL BE POSSIBLE SOUTH OF THE DRY LINE. A COLD FRONT IS STILL ON TRACK TO PUSH THROUGH THE AREA TOMORROW AFTERNOON. THE GFS REMAINS THE FASTEST WITH THE FRONT PUTTING IT AT THE COAST AROUND NOON WHILE THE ECMWF AND NAM PUT THE FRONT AT THE COAST CLOSER TO 6 PM. HAVE CONTINUED TO PREFER THE ECMWF TIMING. HIGH TEMPERATURES TOMORROW COULD VARY BY 5 TO 10 DEGREES DEPENDING ON WHICH SIDE OF THE COLD FRONT ONE IS ON. WEDNESDAY AND THURSDAY LOOK VERY NICE AS HIGH TEMPERATURES REMAIN WELL BELOW NORMAL. THIS IS ALL THANKS TO SOUTHEAST TEXAS BEING ON THE EAST SIDE OF AN UPPER LEVEL LOW BRINGING MUCH COOLER 850 MB TEMPERATURES INTO THE AREA. A SHORT WAVE WILL DIVE SOUTHWARDS ON THE BACK SIDE OF THE LOW HELPING TO REINFORCE THE LONG WAVE TROUGH. THE SHORT WAVE WILL THEN MOVE OVER THE AREA FRIDAY INTO SATURDAY. THIS WILL ALLOW CLOUDS TO RETURN TO THE AREA THURSDAY AFTERNOON IN FRIDAY MORNING. THE EURO HAD BEEN HINTING AT SOME RAIN CHANCES WITH THE SHORT WAVE IN PREVIOUS RUNS BUT HAS SINCE BACKED OFF. THIS MAKES SENSE GIVEN THE LACK OF MOISTURE OVER THE AREA. KEPT WITH CURRENT FORECAST TRENDS AND REDUCED POPS. 23 MARINE... WEAKENING WINDS AND LOWERING SEAS CAN BE EXPECTED THROUGH TONIGHT. A COLD FRONT WILL MOVE INTO THE COASTAL WATERS LATE TUESDAY AFTERNOON INTO TUESDAY EVENING WITH MODERATE STRONG NORTH WINDS AND BUILDING SEAS EXPECTED IN IT WAKE. BEHIND THE FRONT...CAUTION FLAGS WILL BE NEEDED...AND ADVISORIES ARE POSSIBLE. MODERATE NORTH TO NORTHEAST WINDS ARE EXPECTED WEDNESDAY AND THURSDAY. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 59 82 49 74 46 / 10 10 0 0 0 HOUSTON (IAH) 64 86 53 76 49 / 10 10 0 0 0 GALVESTON (GLS) 72 84 62 76 60 / 10 20 0 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...39
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 346 AM CDT TUE APR 29 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW UPPER LOW AND ASSOCIATED SURFACE SYSTEM OVER FAR SOUTHWEST IA. THIS SYSTEM IS EXPECTED TO MOVE SLOWLY NORTHEAST INTO WI THROUGH THIS PERIOD. EXPECT PERIODS OF RAIN TO MOVE NORTH THROUGH THE STATE THROUGH WED AS ENERGY ROTATES AROUND LOW. HEAVIER AREA OF RAIN NOW MOVING MOVING THROUGH SOUTHERN HALF OF STATE. DRY AIR VERY PRESENT ON APX EVENING SOUNDING BEING ADVECTED IN OVER NORTHERN WI ON STRONG EAST WINDS...LIMITING PCPN AMOUNTS SO FAR. THIS DRY AIR VERY EVIDENT OVER FAR NORTH WHERE DEW POINTS STILL IN THE 20S. AS PCPN MOVES IN OVER NORTH SEEING SNOW/SLEET SHOWING UP...THOUGH SURFACE TEMPS STILL MILD SO AM NOT LOOKING AT ANY ACCUMULATION. WILL CONTINUE TO CARRY MIX INTO THE MORNING HOURS. LOW LEVEL TEMP FIELDS POINT TO MAINLY RAIN THROUGH REMAINDER OF THE PERIOD AS WEAK WAA BRINGS 850 TEMP UP TO +2 OVER VILAS COUNTY BY TONIGHT. AS LOW MOVES NORTH LOOK FOR WINDS TO BACK OFF...BECOMING LIGHT LATER TONIGHT INTO WED. MAY SEE SOME FOG WITH LINGERING MOISTURE. WILL ADD TO MARINE ZONES AT THIS TIME AND LET LATER SHIFT DEBATE LAND ZONES. BEST MOISTURE/PW`S OVER 1 INCH NOW OFF TO THE EAST OF STATE...WILL DROP ISSUING ESF WITH LESSER QPF EXPECTED. TEMPS TO REMAIN BELOW SEASONABLE NORMS. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 346 AM CDT TUE APR 29 2014 UNSETTLED CONDITIONS WILL CONTINUE INTO THE WEEKEND AND POSSIBLY EARLY NEXT WEEK. FIRST...UPPER LOW WILL SLOWLY MOVE AWAY FROM THE AREA ON THURSDAY...THEN SEVERAL SYSTEMS MOVING THROUGH THE MEAN FLOW WILL BRING CHANCES FOR SHOWERS AT TIMES FRIDAY INTO EARLY NEXT WEEK. UPPER LOW EXPECTED TO SLOWLY MOVE ACROSS THE AREA WEDNESDAY NIGHT. WILL NEED TO WATCH FOR A POTENTIAL SHARS (SUBTLE HEAVY RAINFALL SIGNATURE EVENT) WITH THESE TYPES OF SYSTEMS DEPENDING ON LOCATION OF SHORTWAVE ENERGY AND LOW LEVEL CONVERGENCE AREAS. THESE TYPES OF SYSTEM COULD BRING CONSIDERABLY MORE RAIN THAT WHAT IS IN THE QPF FORECAST GRID. UNFORTUNATELY...WAY TOO EARLY TO DETERMINE IF OR WHERE THIS TYPE OF EVENT WOULD FORM. EVEN IF A SHARS EVENT DOES DEVELOP...IT WOULD BRING LOCALIZED HEAVIER RAINFALL TOTALS THAN WHAT IS IN THE CURRENT FORECAST AND COULD IMPACT RIVER FORECASTS. COOL CYCLONIC FLOW WILL CONTINUE TO BRING INSTABILITY SHOWERS ON THURSDAY WHICH MAY LINGER INTO THURSDAY EVENING...WITH POSSIBILITY OF AN ISOLATED SHOWER BETWEEN 06Z-12Z FRIDAY. ON FRIDAY...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED COLD FRONT WILL MOVE ACROSS THE REGION ON FRIDAY (MAYBE FRIDAY EVENING ACROSS THE EAST). COOL CYCLONIC FLOW...FORCING ALOFT AND FRONTAL BOUNDARY WITH DEW POINTS POOLING INTO THE LOWER TO MIDDLE 40S WILL BE SUFFICIENT FOR A CHANCE OF SHOWERS. LOOKED AT THUNDER PROSPECTS...DID NOT SUPPORT ADDING THUNDER AT THIS POINT. A STRONGER SHORTWAVE IS EXPECTED MOVE ACROSS THE WESTERN GREAT LAKES ON SATURDAY...BRINGING ANOTHER CHANCE OF SHOWERS. A WEAK BOUNDARY IS EXPECTED TO DROP ACROSS THE AREA DURING THE PEAK HEATING OF THE DAY ON SUNDAY...WARRANTING A CHANCE OF SHOWERS. A FEW SHOWERS MAY LINGER INTO SUNDAY EVENING...THEN DRY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF SUNDAY NIGHT INTO MONDAY MORNING. WITH THE EXPECTED CLOUDS AND SOME RAIN DURING THE DAY TIME HOURS...EXPECTED TEMPERATURES TO RUN BELOW NORMAL FOR MUCH OF THE PERIOD. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1051 PM CDT MON APR 28 2014 A LARGE UPPER LOW SYSTEM SLOWLY CHURNING ACROSS MID SECTION OF THE COUNTRY THIS WEEK WILL CONTINUE TO LIFT BANDS OF SHOWERS NORTH OVER THE STATE FOR MUCH OF THE WEEK. DRY AIR ON EASTERLY WINDS WILL CONTINUE TO FILTER INTO THE AREA TO KEEP CIGS MAINLY AT VFR LEVELS OVER FAR NORTHEAST WISCONSIN FOR A TIME TONIGHT. AS SHOWERS BECOME MORE WIDESPREAD FROM SOUTH TO NORTH OVERNIGHT INTO TUESDAY...CIGS WILL LOWER TO MVFR OR IFR LEVELS. COMPACT PRESSURE GRADIENT AHEAD OF THE LARGE SURFACE LOW OVER THE CENTRAL PLAINS WILL ENSURE GUSTY WINDS AT THE SURFACE FOR A FEW DAYS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......RE AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1110 PM CDT MON APR 28 2014 .SHORT TERM...(TONIGHT AND TUESDAY) ISSUED AT 322 PM CDT MON APR 28 2014 WATCHING THE FRONTAL STRUCTURE TO THE SOUTH CLOSELY AND INSTABILITY TO SEE IF CHANGES IN SEVERE WEATHER FORECASTS NEED TO BE CHANGED...AND TRYING TO BUILD IN BETTER TIMING OVERNIGHT FOR NEXT WAVE OF RAIN. WINDS STILL STRONG...BUT THOSE SHOULD BE DECREASING AFTER MIDNIGHT. GOES WATER VAPOR IMAGERY SHOWING THE MAIN LONG WAVE ANCHORED NEAR CENTRAL NEB WITH A NUMBER OF SHORTWAVE TROUGHS WITHIN THE LARGE TROUGH AREA MOVING NORTH THROUGH IA/MO. IT APPEARS ONE SMALLER CURL CAN BE SEEN IN NERN MO HEADING NORTH. THE AREA HAS BEEN UNDER 300-500MB QG CONVERGENCE LIFT AHEAD OF THIS BROAD TROUGH SPOKE ROTATING NORTHWARD...WITH ISENTROPIC LIFT IN THE LOW-LEVELS NORTH OF THE WARM FRONT...AND THE RAIN TODAY NOW LIFTING NORTH. THE WARM FRONT CONTINUES TO HOLD NEARLY IN PLACE SOUTH OF I-80 AT 19Z. MEANWHILE THE COLD FRONT FROM OMAHA TO CENTRAL MO WAS CLEAR ON VISIBLE IMAGERY AND CONVECTING NOW...AND OVER THE PAST HOURS THE OCCLUSION AND TRIPLE POINT ARE RIPPING EAST...NOW NEAR KDSM. THE STORMS ON THIS OCCLUSION AND COLD FRONT WILL ROTATE NORTHWARD TONIGHT INTO THE FORECAST AREA. 12Z RAOB PRECIPITABLE WATER VALUES ARE NOT AS HIGH AS THE MORNING MODEL INITIALIZATIONS...WITH THE 28.12Z GFS/NAM SHOWING A 1-1.25 INCH PLUME FROM NRN IL INTO SERN MN. KMPX WAS ONLY 0.62 AT 12Z FROM THE RAOB. 1500 FT WINDS OF AREA 88D VAD WINDS ARE STILL IN THE 40-50KT RANGE FROM KMKX- KMPX...EXPLAINING THE CONTINUED WIND GUSTS IN THE 30S MPH. AS THE LATER AFTERNOON PROGRESSES...THE COLD FRONT WILL CONTINUE THE OCCLUSION PROGRESSES SEWRD TOWARD IL. BY EVENING THE TRIPLE POINT SHOULD BE WELL INTO IL WITH A BAND OF TSRA ALONG AND NORTH OF THE OCCLUSION HEADING NORTH TOWARD THE AREA. THE OCCLUSION BOUNDARY STAYS NEAR I-80 IN THE LATEST HRRR RUNS...WITH THE ELEVATED TSRA AND PRECIPITATION BAND ROTATING INTO MN/WI. THE MOST UNSTABLE CAPE ANALYSIS SHOWS 250 J/KG IN THE SOUTHERN FORECAST AREA AT 20Z...WITH ABOUT 500 J/KG APPROACHING THE SOUTHERN FORECAST AREA. AS WITH DAYS PAST...AS THIS TSRA BAND APPROACHES NERN IA AND SWRN WI AFTER 5 PM...CONVECTIVE ACTIVITY IS EXPECTED TO DEGRADE. SOME SMALL HAIL IS POSSIBLE FROM THE STORMS IN THE SOUTHERN FORECAST AREA...BUT THEN A TRANSITION TO A MORE STRATIFORM RAIN REGION WILL OCCUR. THERE IS EXCELLENT AGREEMENT ON THE MODEL GUIDANCE ON THE BAND ROTATING NORTH THROUGH THE AREA OVERNIGHT. HAVE FORECAST AMOUNTS OF LESS THAN ONE-HALF OF AN INCH. WITH MODELS TOO HIGH ON PRECIPITABLE WATER...HAVE DISCOUNTED HEAVIER RAINFALL TOTALS SUCH AS THE 28.12Z. THE BAND WILL ROTATE INTO THE NORTHERN FORECAST AREA TUESDAY MORNING AND SLOW ITS PROGRESS AS THE SURFACE LOW SHIFTS TOWARD ROCKFORD IL. THIS WILL PROVIDE A QUICK WARM UP TO THE BOUNDARY LAYER AND SOME INSTABILITY ACROSS SOUTHWEST WI FOR A TIME TUESDAY. HAVE ADDED SOME THUNDER THERE BUT DO NOT EXPECT MORE THAN PEA SIZED HAIL WITH 250 J/KG OF CAPE OR SO. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 322 PM MON APR 28 2014 TUESDAY NIGHT THROUGH THURSDAY NIGHT THE AREA WILL BE RIGHT UNDER THE OCCLUDED DEEP LOW WITH SPOKES OF ENERGY CONTINUING TO ROTATE THROUGH THE AREA. THE MODEL GUIDANCE AGREES ON THE BIG PICTURE BUT THE DETAILS OF TIMING ON RAIN CHANCES ARE ALL OVER THE PLACE AMONG ALL THE AVAILABLE MODELS. HAVE KEPT THIS PERIOD SHOWERY WITH MUCH LIGHTER WINDS THAN WE HAVE SEEN. FAIRLY SATURATED CONDITIONS AND SHORTWAVES THAT WILL BE ROTATING THROUGH THE LONG WAVE WILL BRING MORE ORGANIZED SHOWER AREAS I AM SURE. AT THIS POINT...RAISED RAIN CHANCES THROUGH THIS PERIOD TO AT LEAST 60 PERCENT WITH MORE DETAIL TO BE ADDED AS WE GET CLOSER TO THOSE DAYS AND CAN IDENTIFY WHERE TO IMPROVE THE FORECAST. COOL AND CLOUDY WITH LIGHT RAINFALL /LESS THAN ONE TENTH PER 12 HOURS/ FOR MOST EVERYWHERE. FRIDAY THROUGH MONDAY A BELOW NORMAL TEMPERATURE PERIOD. LONG WAVE TROUGH AND SHORTWAVE ACTIVITY SPOKING AROUND THE LOW WILL MAKE FOR DETAILS IN THIS PERIOD DIFFICULT. BY FRIDAY IT WOULD APPEAR THE MODEL CONSENSUS SUGGEST THE AREA INTO NORTHWEST FLOW WHICH CAUSES ITS OWN ISSUES FOR TIMING OF SHOWERS WITH SHORTWAVE TROUGHS. HEIGHTS RISE MORE OVER THE GREAT LAKES ON FRIDAY NIGHT AND SATURDAY AS ENERGY CRASHES ONTO THE WEST COAST. THIS ENERGY THEN EJECTS INTO THE PLAINS BY LATER SATURDAY WITH CYCLOGENESIS AND SOUTHERLY RETURN FLOW ACTIVATING ON THE FRONT TO THE SOUTHWEST. FOR A 150 HOUR FORECAST...THERE IS PRETTY GOOD AGREEMENT WITH THE LATEST TWO RUNS OF THE ECMWF/GFS MODELS THAT SHOWERS/RAIN WILL SPREAD ACROSS THE REGION SUNDAY WITH THE NORMAL WARM FRONTAL LIFT SIGNALS OF ISENTROPIC LIFT...MOISTURE TRANSPORT CONVERGENCE. WHILE PLACEMENT IS VARIED...THE GENERAL AGREEMENT ADDS TO CONFIDENCE. BOTTOM LINE IS SATURDAY LOOKS LIKE THE DRIER DAY STILL BUT CONFIDENCE IS SOMEWHAT LOW WITH NORTHWEST FLOW VERY DIFFICULT TO FORECAST 5 DAYS OUT. TEMPERATURES DONT LOOK TO REBOUND MUCH UNTIL SATURDAY...BUT CLOUDS MAKE ALL THE DIFFERENCE THIS TIME OF YEAR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1110 PM CDT MON APR 28 2014 CLOSED...VERTICALLY STACKED LOW WILL BE THE WEATHER MAKER OVER THE NEXT FEW DAYS. THIS WILL KEEP KRST/KLSE UNDER A PROLONGED PERIOD OF MVFR/IFR CIGS...WITH BOUTS OF MVFR VSBYS DURING -SHRA/RA. TIMING THE PROBABLE WET AND DRY PERIODS IS CHALLENGING...AND HAVE BEEN LEANING ON -SHRA OR VCSH WITH NO VSBY RESTRICTION TO SHOW CONFIDENCE. MODELS DO FAVOR KEEPING KRST IN RAIN MORE OFTEN THEN NOT THROUGH MUCH OF TUE...WHILE KLSE COULD SPEND MORE TIME IN A DRIER REGION. WINDS WILL STAY STRONG TONIGHT...BUT AS THE LOW INCHES NORTHWARD TUE...EXPECT SOME SLACKENING IN THE PRESSURE GRADIENT...AND A REDUCTION IN WIND SPEEDS. DIRECTION WILL BECOME MORE NORTHERLY TUE...THEN SHIFTING NORTHWEST LATE TUE NIGHT. LLWS REMAINS A CONCERN AT KLSE WITH AROUND 50 KTS AT 2 KFT. WILL CONTINUE A MENTION IN FORECAST INTO THE OVERNIGHT HOURS. && .HYDROLOGY... ISSUED AT 322 PM CDT MON APR 28 2014 AFTER RECEIVING LESS RAIN OVERNIGHT THAN ORIGINALLY THOUGHT...THE RIVER SITUATION SEEMS LIKE IT WILL BEHAVE FOR THIS STORM. WE ARE EXPECTING ABOUT 0.50 TO 0.75 INCHES OF RAIN TONIGHT AND TUESDAY FOR MOST AREAS WHICH WILL MEAN BANKFULL RIVER RISES FOR MOST RIVERS...AND A LOW FLOODING THREAT. THE KICKAPOO MAY BE THE CLOSEST RIVER TO FLOODING. MAYBE THE MAIN STORY IS THE MISSISSIPPI RIVER THAT WILL SWALLOW ALL THE INCOMING TRIBUTARY WATER AND CONTINUE TO RISE ALL NEXT WEEK. FROM WINONA MN SOUTH...IT APPEARS THE MISSISSIPPI RIVER WILL BE APPROACHING MINOR FLOOD LEVELS BY LATER THIS WEEK...WITH FLOODING LIKELY FURTHER NORTH. THE FLOOD WATCH HAS BEEN ISSUED FOR THE WINONA AND SOUTH FLOODING THREAT. AFTER TONIGHT...RAINFALL AMOUNTS WILL TURN MORE SHOWERY AS THE GULF MOISTURE PLUME IS SHUNTED EAST. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR WIZ041-053-054-061. MN...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR MNZ088-096. IA...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR IAZ011-030. && SHORT TERM...BAUMGARDT LONG TERM....BAUMGARDT AVIATION.....RIECK HYDROLOGY....BAUMGARDT
AREA FORECAST DISCUSSION
NWS ALBANY NY
625 AM EDT TUE APR 29 2014 .SYNOPSIS... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. TEMPERATURES WILL REMAIN QUITE COOL THROUGH WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 630 AM EDT...LOW CLOUDS HAVE OVERSPREAD MOST OF THE REGION...WITH THE EXCEPTION OF PORTIONS OF THE WESTERN ADIRONDACKS AND MOHAWK VALLEY. THE COMBINATION OF CLOUDS...AND SOME WIND...HAVE KEPT TEMPS FROM FALLING MUCH OVERNIGHT...AND ARE GENERALLY STILL IN THE MID 40S TO LOWER 50S. TEMPS MAY FALL ANOTHER 2-4 DEGREES THROUGH SUNRISE...ESP ACROSS PORTIONS OF THE BERKSHIRES AND SOUTHERN VT...AS SLIGHTLY COOLER AIR SPREADS WESTWARD...ALONG WITH SOME ADIABATIC COOLING FROM LIFTING ACROSS EAST FACING TERRAIN. ALSO...SOME ISOLATED SPRINKLES/PATCHY DRIZZLE HAVE DEVELOPED ACROSS PORTIONS OF THE SOUTHERN GREENS/BERKSHIRES...AND THE GREATER CAPITAL REGION. HAVE ADDED MENTION OF SPRINKLES FOR THE NEXT 2-4 HOURS TO ACCOUNT FOR THIS. AREAS OF THE HELDERBERGS AND SE CATSKILLS WILL ALSO BE SUSCEPTIBLE TO THESE SPRINKLES/DRIZZLE AS WELL. OTHERWISE...THROUGH NOON...EXPECT MOSTLY CLOUDY SKIES TO CONTINUE...ALTHOUGH A FEW BREAKS IN THE CLOUDS ARE POSSIBLE...ESP ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE A DOWNSLOPING E/SE FLOW MAY HELP TO OCCASIONALLY BREAK UP THE LOWER CLOUD DECK. OTHERWISE...LITTLE IN THE WAY OF RAINFALL IS EXPECTED THROUGH NOONTIME...WITH THE POSSIBLE EXCEPTION BEING SOME SPOTTY DRIZZLE OR SPRINKLES ACROSS UPSLOPE AREAS OF THE SOUTHERN GREEN MTNS/BERKSHIRES...AND PERHAPS THE EASTERN CATSKILLS. TEMPS SHOULD SLOWLY RISE INTO AND THROUGH THE LOWER/MID 50S IN MOST AREAS...AND PERHAPS UPPER 50S ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE SOME BRIEF BREAKS OF SUN AND WARMING FROM DOWNSLOPING IS POSSIBLE. THIS AFTERNOON...LIGHT RAIN SHOULD BEGIN TO OVERSPREAD THE REGION FROM WEST/SOUTHWEST TO EAST/NORTHEAST. HAVE FOLLOWED THE RUC 13/HRRR AND HI-RES WRF FOR GENERAL TIMING...WHICH BRINGS RAIN INTO THE WESTERN MOHAWK VALLEY/SCHOHARIE VALLEY/EASTERN CATSKILLS AND MID HUDSON VALLEY MAINLY W OF THE HUDSON RIVER BETWEEN 1-3 PM...INTO THE CENTRAL/EASTERN MOHAWK VALLEY...CAPITAL REGION...MID HUDSON VALLEY E OF THE HUDSON RIVER AND WESTERN LITCHFIELD CO BETWEEN ROUGHLY 2 AND 4 PM...ACROSS THE LAKE GEORGE REGION/SE ADIRONDACKS/UPPER HUDSON VALLEY AND EASTERN LITCHFIELD CO BETWEEN 4-6 PM...AND EVENTUALLY INTO SOUTHERN VT AND THE BERKSHIRES BETWEEN 6-8 PM. TEMPS WILL LIKELY FALL SEVERAL DEGREES ONCE THE RAIN BEGINS DUE TO WET BULB/EVAPORATIONAL COOLING. EAST/SOUTHEAST WINDS WILL INCREASE THROUGH THE DAY...WITH SOME GUSTS POSSIBLY REACHING 20-25 MPH AT TIMES...EXCEPT 25-35 MPH ACROSS PORTIONS OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... TONIGHT...A SURGE OF ISENTROPIC LIFT...MOST NOTABLY ALONG THE 300 K SFC...WILL DEVELOP FROM W TO E ACROSS THE REGION OVERNIGHT. EXPECT PERIODS OF LIGHT TO MODERATE RAIN OVERNIGHT...WITH THE STEADIEST AND MOST PERSISTENT RAIN EXPECTED ACROSS PORTIONS OF THE WESTERN MOHAWK VALLEY AND SW ADIRONDACKS...AS WELL AS ACROSS THE EASTERN CATSKILLS. SOME SLEET COULD MIX IN AT TIMES ACROSS HIGHER ELEVATIONS OF THE SW ADIRONDACKS...SOUTHERN VT AND NORTHERN BERKSHIRES...AND PERHAPS EVEN THE EASTERN CATSKILLS AS A DRY WEDGE AROUND 3500-5000 FT AGL ADVECTS WESTWARD...WHILE RAIN FALLS THROUGH THIS LAYER. GUSTY E/SE WINDS WILL CONTINUE...OCCASIONALLY GUSTING UP TO 25-35 MPH AT TIMES ACROSS THE HIGHER TERRAIN OF WESTERN NEW ENGLAND AND THE TACONICS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. WED-THU MORNING...THE COMBINATION OF ISENTROPIC LIFT...LOW LEVEL CONVERGENCE...AND OVERALL SYNOPTIC FORCING...AS WELL AS THE CLOSEST PROXIMITY OF THE LOW LEVEL JET...WILL MOVE ACROSS THE REGION LATE WED INTO WED NT...RESULTING IN THE PERIOD OF HEAVIEST RAINFALL. THE RAIN MAY BE MORE INTERMITTENT AT TIMES WED AM...BEFORE SEVERAL SURGES OF MODERATE TO EVEN HEAVY RAIN DEVELOP LATE WED AFTN INTO WED NT. IN ADDITION...SHOWALTER INDICES ARE FORECAST TO DIP INTO THE 0 TO -2 C RANGE WED NT FROM AROUND INTERSTATE 90 SOUTHWARD. HAVE THEREFORE INCLUDED SLIGHT CHC OF THUNDER FOR CENTRAL AND SOUTHERN AREAS. BY EARLY THU...THE BEST AXIS OF FORCING AND ELEVATED INSTABILITY SHOULD SHIFT PRIMARILY INTO THE MID HUDSON VALLEY...NW CT...AND PERHAPS SW MA...WHERE THE HEAVIEST RAINFALL SHOULD STILL BE OCCURRING. GIVEN THAT THE SOUTH TO SOUTHWEST FLOW THROUGH A DEEP LAYER OF THE MIDDLE/UPPER TROPOSPHERE WILL LINE UP...THERE IS SOME POTENTIAL FOR TRAINING OF HEAVIER RAINFALL. HOWEVER...THERE REMAINS SOME UNCERTAINTY AS TO WHERE ANY POTENTIAL AXIS OF HEAVIEST AND MOST PERSISTENT RAINFALL WILL OCCUR...AS SOME MODELS SUGGEST THIS AXIS COULD SET UP JUST SOUTH AND WEST OF OUR REGION. IN ADDITION...THERE IS SOME POSSIBILITY THAT DEEPER CONVECTION CLOSE TO THE DEVELOPING TRIPLE POINT ACROSS NJ OR NYC/LI COULD LIMIT THE OVERALL MOISTURE TRANSPORT FURTHER N INTO OUR REGION. DUE TO THIS LINGERING UNCERTAINTY...WILL HOLD OFF ON ANY FLOOD WATCH AT THIS TIME. AS FOR TEMPS...WED SHOULD BE QUITE COOL GIVEN CLOUDS AND RAINFALL...WITH MAXES GENERALLY ONLY REACHING THE MID 40S TO LOWER 50S. TEMPS WILL HOLD NEARLY STEADY OR FALL SLIGHTLY FROM THESE MAX TEMPS EARLY WED NT...BEFORE GRADUALLY RISING AGAIN LATE WED NT. ALSO...WILL HAVE TO WATCH FOR STRONG WIND POTENTIAL WED AFTERNOON AND NIGHT...ESP ACROSS THE HIGHER TERRAIN OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AND PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS...WHERE SOME EAST/SOUTHEAST WINDS COULD GUST OVER 45 MPH. IF THIS POTENTIAL INCREASES FURTHER...THEN WIND ADVISORIES MAY NEED TO BE ISSUED FOR THESE AREAS. THU AFTN-THU NT...AN OCCLUDED FRONTAL BOUNDARY SHOULD MOVE EAST OF THE REGION BY THU AFTN. HOWEVER...SOME SHOWERS WILL REMAIN POSSIBLE AS THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. SHOWERS SHOULD GRADUALLY DECREASE IN AREAL COVERAGE THU NT. TEMPS ON THU SHOULD REACH 65-70 IN VALLEYS...AND MID 50S TO MID 60S FOR HIGHER ELEVATIONS...WITH EVEN WARMER MAX TEMPS POSSIBLE IF SOME BREAKS OF SUN DEVELOP IN THE AFTERNOON. EXPECT THU NT MINS TO FALL INTO THE MID 30S TO LOWER 40S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AN UNSETTLED PATTERN WILL CONTINUE THROUGH MUCH OF THE LONG TERM PERIOD. FOR FRIDAY...EXPECT WIDELY SCATTERED TO SCATTERED SHOWERS WITH THE HIGHEST POPS ACRS THE NORTHWEST THIRD OF THE FA. THIS WILL BE DUE TO THE MID LEVEL TROUGH AXIS PASSING ACROSS THE FA WITH SEVERAL VORT MAXS ROTATING AROUND THE BASE OF THE TROUGH. HIGHS ON FRIDAY ARE EXPECTED TO BE IN THE UPPER 40S AND LOWER 50S TO MID 60S ACRS THE SE PTN OF THE FA. BY FRIDAY NIGHT. THE BEST CHANCE OF SEEING SHOWERS WILL BE ACRS THE WRN ADIRONDACKS WHERE SOME LAKE ENHANCED SHOWERS ARE POSSIBLE. LOWS FRIDAY NIGHT WILL RANGE FROM THE MID 30S NORTHWEST TO MID 40S SOUTHEAST. SO LIGHT SNOW ACCUMULATION IS POSSIBLE ACROSS THE WESTERN ADIRONDACKS. ON SATURDAY AND SATURDAY NIGHT...THERE WILL BE ANOTHER SHORTWAVE TROUGH AXIS IN CLOSE PROXIMITY TO OUR REGION. HAVE GONE WITH LIKELY POPS SATURDAY ACRS THE NORTHWEST THIRD OF THE FA WITH CHANCE POPS ELSEWHERE AND CHANCE POPS ACRS THE FA SATURDAY NIGHT. HIGHS WILL RANGE FROM THE MID 50S TO MID 60S WITH LOWS SATURDAY NIGHT IN THE MID 30S TO MID 40S ONCE AGAIN.. SUNDAY INTO MONDAY...A STRONG CLOSED OFF UPPER LEVEL LOW WILL APPROACH THE REGION...AS IT ROTATES AROUND THE BROAD SCALE UPPER LEVEL TROUGH SITUATED OVER EASTERN CANADA. THIS WILL PROVIDE LIFT FOR SOME ADDITIONAL RAIN SHOWERS ALTHOUGH THEIR WILL BE A GRADUAL DECREASE IN POPS AS WE GO FROM SUNDAY INTO MONDAY. EXPECT HIGHS ON SUNDAY AND MONDAY TO RANGE FROM THE MID 50S NORTHWEST TO THE MID 60S SOUTHEAST WITH LOWS SUNDAY NIGHT IN THE MID 30S TO MID 40S. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... A SPRAWLING STORM SYSTEM OVER THE GREAT PLAINS WILL SLOWLY APPROACH THE REGION OVER THE NEXT FEW DAYS. VFR/MVFR CONDITIONS ARE EXPECTED AT THE TAF SITES FROM THIS MORNING THROUGH EARLY THIS AFTERNOON. CIGS WL GENERALLY BE BKN-OVC 015-035 WITH HIGH LEVEL CLOUDS ABOVE. RAIN SHOWERS WILL SLOWLY SPREAD FROM SOUTHWEST TO NORTHEAST ACROSS THE REGION DURING THE AFTN HOURS. IT MAY TAKE UNTIL THE LATE AFTN OR EVENING FOR SHOWERS TO REACH KALB/KGFL...AND CONDITIONS SHOULD INITIALLY BE VFR FOR THE TAF SITES. FURTHER SOUTH...KPOU/KPSF MAY SEE MVFR CIGS/VSBYS BY LATE IN THE DAY...AS COVERAGE AND INTENSITY OF SHOWERS INCREASE. MOST TAF SITES CAN EXPECT MVFR CONDITIONS WITH REDUCED VISIBILITY BY LATE EVENING WITH SHOWERS...EXCEPT FOR KPSF WHICH WILL HAVE IFR CONDITIONS. IFR CONDITIONS ARE EXPECTED AT ALL THE TAF SITES LATE AT NIGHT GENERALLY AFTER 08Z. WITH AN INCREASING PRESSURE GRADIENT...E-SE WINDS OF 5-10 KTS TONIGHT WILL INCREASE TO AROUND 10-15 KTS ON TUESDAY...AND BE STRONGEST DURING THE AFTN/EVENING HOURS. WINDS MAY SHIFT MORE TO TH EAST LATE TONIGHT EXCEPT AT KGFL WHERE WINDS WILL BE NW. OUTLOOK... WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. PDS RA...TSRA. THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... WIND GUSTS OF 25-35 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON...ESPECIALLY ACROSS HIGHER ELEVATIONS OF WESTERN NEW ENGLAND... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. MINIMUMS RELATIVE HUMIDITIES WILL FALL INTO THE 30-40 PERCENT RANGE THIS AFTERNOON ACROSS THE UPPER HUDSON VALLEY AND SOUTHERN VT...AND 40-50 PERCENT ELSEWHERE. THE RH WILL RECOVER TO 75-90 PERCENT TONIGHT...WITH A WETTING RAINFALL DEVELOPING. THE RH WILL FALL INTO THE 60-70 PERCENT RANGE WED AFTERNOON. EAST TO SOUTHEAST WINDS WILL INCREASE TO 15-25 MPH TODAY...WITH SOME GUSTS UP TO 35 MPH POSSIBLE ACROSS HIGHER ELEVATIONS. THESE WINDS WILL DECREASE SLIGHTLY TONIGHT TO 10-20 MPH...THEN INCREASE ONCE AGAIN BY WED AFTERNOON TO 15-30 MPH. && .HYDROLOGY... THE POTENTIAL FOR HEAVY RAINFALL CONTINUES TO INCREASE...ESPECIALLY FOR THE SE CATSKILLS...MID HUDSON VALLEY AND INTO NW CT... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BRING AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER.THE RAIN COULD COME DOWN HEAVY AT TIMES LATE WEDNESDAY AFTERNOON THROUGH EARLY THURSDAY MORNING...RESULTING IN THE BULK OF THE RAINFALL. AT THIS TIME...EXPECTED RAINFALL FOR TUESDAY THROUGH THURSDAY IS 1 TO 2 INCHES...WITH 2 TO 3 INCHES ACROSS THE CENTRAL AND SOUTHEASTERN CATSKILLS...MID HUDSON VALLEY INTO THE BERKSHIRES AND ACROSS LITCHFIELD COUNTY. THIS RAINFALL WOULD RESULT IN WIDESPREAD SIGNIFICANT WITHIN BACK RISES ON RIVERS AND STREAMS...AND MINOR FLOODING OF URBAN...LOW LYING AND POOR DRAINAGE AREAS DURING PERIOD OF HEAVY RAINFALL. BASED ON CURRENT FORECASTS...SOME OF THE RIVER POINTS IN THE HOUSATONIC BASIN WOULD REACH ACTION STAGE WITH CLOSE TO MINOR FLOOD POSSIBLE IN THE LOWER PORTION OF THE BASIN AT GAYLORDSVILLE AND STEVENSON DAM. THERE IS STILL UNCERTAINTY IN THE FORECAST SINCE WE ARE DEALING WITH A CUT OFF LOW PRESSURE SYSTEM. SMALL CHANGES IN THE FORECASTED RAINFALL COULD LEAD TO FLOODING ISSUES. AS OF NOW...THE HEAVIEST AXIS OF MOST PERSISTENT RAINFALL LOOKS TO BE JUST SOUTHWEST OF OUR REGION. HOWEVER...SHOULD FUTURE FORECASTS SUGGEST THAT THIS AXIS SHIFTS FURTHER NORTH AND EAST...THEN A FLOOD WATCH MAY HAVE TO BE ISSUED FOR PORTIONS OF THE FORECAST AREA. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/FRUGIS/KL NEAR TERM...KL SHORT TERM...KL LONG TERM...FRUGIS/11 AVIATION...11 FIRE WEATHER...IAA/KL HYDROLOGY...IAA/KL
AREA FORECAST DISCUSSION
NWS ALBANY NY
615 AM EDT TUE APR 29 2014 .SYNOPSIS... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. TEMPERATURES WILL REMAIN QUITE COOL THROUGH WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 445 AM EDT...LOW CLOUDS HAVE OVERSPREAD MOST OF THE REGION...WITH THE EXCEPTION OF PORTIONS OF THE WESTERN ADIRONDACKS AND MOHAWK VALLEY. THE COMBINATION OF CLOUDS...AND SOME WIND...HAVE KEPT TEMPS FROM FALLING MUCH OVERNIGHT...AND ARE GENERALLY STILL IN THE MID 40S TO LOWER 50S. TEMPS MAY FALL ANOTHER 2-4 DEGREES THROUGH SUNRISE...ESP ACROSS PORTIONS OF THE BERKSHIRES AND SOUTHERN VT...AS SLIGHTLY COOLER AIR SPREADS WESTWARD...ALONG WITH SOME ADIABATIC COOLING FROM LIFTING ACROSS EAST FACING TERRAIN. THROUGH THIS MORNING...EXPECT MOSTLY CLOUDY SKIES TO CONTINUE...ALTHOUGH A FEW BREAKS IN THE CLOUDS ARE POSSIBLE...ESP ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE A DOWNSLOPING E/SE FLOW MAY HELP TO OCCASIONALLY BREAK UP THE LOWER CLOUD DECK. OTHERWISE...LITTLE IN THE WAY OF RAINFALL IS EXPECTED THROUGH NOONTIME...WITH THE POSSIBLE EXCEPTION BEING SOME SPOTTY DRIZZLE OR SPRINKLES ACROSS UPSLOPE AREAS OF THE SOUTHERN GREEN MTNS/BERKSHIRES...AND PERHAPS THE EASTERN CATSKILLS. TEMPS SHOULD SLOWLY RISE INTO AND THROUGH THE LOWER/MID 50S IN MOST AREAS...AND PERHAPS UPPER 50S ACROSS PORTIONS OF THE UPPER HUDSON VALLEY WHERE SOME BRIEF BREAKS OF SUN AND WARMING FROM DOWNSLOPING IS POSSIBLE. THIS AFTERNOON...LIGHT RAIN SHOULD BEGIN TO OVERSPREAD THE REGION FROM WEST/SOUTHWEST TO EAST/NORTHEAST. HAVE FOLLOWED THE RUC 13/HRRR AND HI-RES WRF FOR GENERAL TIMING...WHICH BRINGS RAIN INTO THE WESTERN MOHAWK VALLEY/SCHOHARIE VALLEY/EASTERN CATSKILLS AND MID HUDSON VALLEY MAINLY W OF THE HUDSON RIVER BETWEEN 1-3 PM...INTO THE CENTRAL/EASTERN MOHAWK VALLEY...CAPITAL REGION...MID HUDSON VALLEY E OF THE HUDSON RIVER AND WESTERN LITCHFIELD CO BETWEEN ROUGHLY 2 AND 4 PM...ACROSS THE LAKE GEORGE REGION/SE ADIRONDACKS/UPPER HUDSON VALLEY AND EASTERN LITCHFIELD CO BETWEEN 4-6 PM...AND EVENTUALLY INTO SOUTHERN VT AND THE BERKSHIRES BETWEEN 6-8 PM. TEMPS WILL LIKELY FALL SEVERAL DEGREES ONCE THE RAIN BEGINS DUE TO WET BULB/EVAPORATIONAL COOLING. EAST/SOUTHEAST WINDS WILL INCREASE THROUGH THE DAY...WITH SOME GUSTS POSSIBLY REACHING 20-25 MPH AT TIMES...EXCEPT 25-35 MPH ACROSS PORTIONS OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... TONIGHT...A SURGE OF ISENTROPIC LIFT...MOST NOTABLY ALONG THE 300 K SFC...WILL DEVELOP FROM W TO E ACROSS THE REGION OVERNIGHT. EXPECT PERIODS OF LIGHT TO MODERATE RAIN OVERNIGHT...WITH THE STEADIEST AND MOST PERSISTENT RAIN EXPECTED ACROSS PORTIONS OF THE WESTERN MOHAWK VALLEY AND SW ADIRONDACKS...AS WELL AS ACROSS THE EASTERN CATSKILLS. SOME SLEET COULD MIX IN AT TIMES ACROSS HIGHER ELEVATIONS OF THE SW ADIRONDACKS...SOUTHERN VT AND NORTHERN BERKSHIRES...AND PERHAPS EVEN THE EASTERN CATSKILLS AS A DRY WEDGE AROUND 3500-5000 FT AGL ADVECTS WESTWARD...WHILE RAIN FALLS THROUGH THIS LAYER. GUSTY E/SE WINDS WILL CONTINUE...OCCASIONALLY GUSTING UP TO 25-35 MPH AT TIMES ACROSS THE HIGHER TERRAIN OF WESTERN NEW ENGLAND AND THE TACONICS...AS WELL AS PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS. WED-THU MORNING...THE COMBINATION OF ISENTROPIC LIFT...LOW LEVEL CONVERGENCE...AND OVERALL SYNOPTIC FORCING...AS WELL AS THE CLOSEST PROXIMITY OF THE LOW LEVEL JET...WILL MOVE ACROSS THE REGION LATE WED INTO WED NT...RESULTING IN THE PERIOD OF HEAVIEST RAINFALL. THE RAIN MAY BE MORE INTERMITTENT AT TIMES WED AM...BEFORE SEVERAL SURGES OF MODERATE TO EVEN HEAVY RAIN DEVELOP LATE WED AFTN INTO WED NT. IN ADDITION...SHOWALTER INDICES ARE FORECAST TO DIP INTO THE 0 TO -2 C RANGE WED NT FROM AROUND INTERSTATE 90 SOUTHWARD. HAVE THEREFORE INCLUDED SLIGHT CHC OF THUNDER FOR CENTRAL AND SOUTHERN AREAS. BY EARLY THU...THE BEST AXIS OF FORCING AND ELEVATED INSTABILITY SHOULD SHIFT PRIMARILY INTO THE MID HUDSON VALLEY...NW CT...AND PERHAPS SW MA...WHERE THE HEAVIEST RAINFALL SHOULD STILL BE OCCURRING. GIVEN THAT THE SOUTH TO SOUTHWEST FLOW THROUGH A DEEP LAYER OF THE MIDDLE/UPPER TROPOSPHERE WILL LINE UP...THERE IS SOME POTENTIAL FOR TRAINING OF HEAVIER RAINFALL. HOWEVER...THERE REMAINS SOME UNCERTAINTY AS TO WHERE ANY POTENTIAL AXIS OF HEAVIEST AND MOST PERSISTENT RAINFALL WILL OCCUR...AS SOME MODELS SUGGEST THIS AXIS COULD SET UP JUST SOUTH AND WEST OF OUR REGION. IN ADDITION...THERE IS SOME POSSIBILITY THAT DEEPER CONVECTION CLOSE TO THE DEVELOPING TRIPLE POINT ACROSS NJ OR NYC/LI COULD LIMIT THE OVERALL MOISTURE TRANSPORT FURTHER N INTO OUR REGION. DUE TO THIS LINGERING UNCERTAINTY...WILL HOLD OFF ON ANY FLOOD WATCH AT THIS TIME. AS FOR TEMPS...WED SHOULD BE QUITE COOL GIVEN CLOUDS AND RAINFALL...WITH MAXES GENERALLY ONLY REACHING THE MID 40S TO LOWER 50S. TEMPS WILL HOLD NEARLY STEADY OR FALL SLIGHTLY FROM THESE MAX TEMPS EARLY WED NT...BEFORE GRADUALLY RISING AGAIN LATE WED NT. ALSO...WILL HAVE TO WATCH FOR STRONG WIND POTENTIAL WED AFTERNOON AND NIGHT...ESP ACROSS THE HIGHER TERRAIN OF THE SOUTHERN GREENS/BERKSHIRES/TACONICS/LITCHFIELD HILLS...AND PORTIONS OF THE EASTERN CATSKILLS AND WESTERN ADIRONDACKS...WHERE SOME EAST/SOUTHEAST WINDS COULD GUST OVER 45 MPH. IF THIS POTENTIAL INCREASES FURTHER...THEN WIND ADVISORIES MAY NEED TO BE ISSUED FOR THESE AREAS. THU AFTN-THU NT...AN OCCLUDED FRONTAL BOUNDARY SHOULD MOVE EAST OF THE REGION BY THU AFTN. HOWEVER...SOME SHOWERS WILL REMAIN POSSIBLE AS THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. SHOWERS SHOULD GRADUALLY DECREASE IN AREAL COVERAGE THU NT. TEMPS ON THU SHOULD REACH 65-70 IN VALLEYS...AND MID 50S TO MID 60S FOR HIGHER ELEVATIONS...WITH EVEN WARMER MAX TEMPS POSSIBLE IF SOME BREAKS OF SUN DEVELOP IN THE AFTERNOON. EXPECT THU NT MINS TO FALL INTO THE MID 30S TO LOWER 40S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AN UNSETTLED PATTERN WILL CONTINUE THROUGH MUCH OF THE LONG TERM PERIOD. FOR FRIDAY...EXPECT WIDELY SCATTERED TO SCATTERED SHOWERS WITH THE HIGHEST POPS ACRS THE NORTHWEST THIRD OF THE FA. THIS WILL BE DUE TO THE MID LEVEL TROUGH AXIS PASSING ACROSS THE FA WITH SEVERAL VORT MAXS ROTATING AROUND THE BASE OF THE TROUGH. HIGHS ON FRIDAY ARE EXPECTED TO BE IN THE UPPER 40S AND LOWER 50S TO MID 60S ACRS THE SE PTN OF THE FA. BY FRIDAY NIGHT. THE BEST CHANCE OF SEEING SHOWERS WILL BE ACRS THE WRN ADIRONDACKS WHERE SOME LAKE ENHANCED SHOWERS ARE POSSIBLE. LOWS FRIDAY NIGHT WILL RANGE FROM THE MID 30S NORTHWEST TO MID 40S SOUTHEAST. SO LIGHT SNOW ACCUMULATION IS POSSIBLE ACROSS THE WESTERN ADIRONDACKS. ON SATURDAY AND SATURDAY NIGHT...THERE WILL BE ANOTHER SHORTWAVE TROUGH AXIS IN CLOSE PROXIMITY TO OUR REGION. HAVE GONE WITH LIKELY POPS SATURDAY ACRS THE NORTHWEST THIRD OF THE FA WITH CHANCE POPS ELSEWHERE AND CHANCE POPS ACRS THE FA SATURDAY NIGHT. HIGHS WILL RANGE FROM THE MID 50S TO MID 60S WITH LOWS SATURDAY NIGHT IN THE MID 30S TO MID 40S ONCE AGAIN.. SUNDAY INTO MONDAY...A STRONG CLOSED OFF UPPER LEVEL LOW WILL APPROACH THE REGION...AS IT ROTATES AROUND THE BROAD SCALE UPPER LEVEL TROUGH SITUATED OVER EASTERN CANADA. THIS WILL PROVIDE LIFT FOR SOME ADDITIONAL RAIN SHOWERS ALTHOUGH THEIR WILL BE A GRADUAL DECREASE IN POPS AS WE GO FROM SUNDAY INTO MONDAY. EXPECT HIGHS ON SUNDAY AND MONDAY TO RANGE FROM THE MID 50S NORTHWEST TO THE MID 60S SOUTHEAST WITH LOWS SUNDAY NIGHT IN THE MID 30S TO MID 40S. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... A SPRAWLING STORM SYSTEM OVER THE GREAT PLAINS WILL SLOWLY APPROACH THE REGION OVER THE NEXT FEW DAYS. VFR/MVFR CONDITIONS ARE EXPECTED AT THE TAF SITES FROM THIS MORNING THROUGH EARLY THIS AFTERNOON. CIGS WL GENERALLY BE BKN-OVC 015-035 WITH HIGH LEVEL CLOUDS ABOVE. RAIN SHOWERS WILL SLOWLY SPREAD FROM SOUTHWEST TO NORTHEAST ACROSS THE REGION DURING THE AFTN HOURS. IT MAY TAKE UNTIL THE LATE AFTN OR EVENING FOR SHOWERS TO REACH KALB/KGFL...AND CONDITIONS SHOULD INITIALLY BE VFR FOR THE TAF SITES. FURTHER SOUTH...KPOU/KPSF MAY SEE MVFR CIGS/VSBYS BY LATE IN THE DAY...AS COVERAGE AND INTENSITY OF SHOWERS INCREASE. MOST TAF SITES CAN EXPECT MVFR CONDITIONS WITH REDUCED VISIBILITY BY LATE EVENING WITH SHOWERS...EXCEPT FOR KPSF WHICH WILL HAVE IFR CONDITIONS. IFR CONDITIONS ARE EXPECTED AT ALL THE TAF SITES LATE AT NIGHT GENERALLY AFTER 08Z. WITH AN INCREASING PRESSURE GRADIENT...E-SE WINDS OF 5-10 KTS TONIGHT WILL INCREASE TO AROUND 10-15 KTS ON TUESDAY...AND BE STRONGEST DURING THE AFTN/EVENING HOURS. WINDS MAY SHIFT MORE TO TH EAST LATE TONIGHT EXCEPT AT KGFL WHERE WINDS WILL BE NW. OUTLOOK... WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. PDS RA...TSRA. THURSDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... WIND GUSTS OF 25-35 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON...ESPECIALLY ACROSS HIGHER ELEVATIONS OF WESTERN NEW ENGLAND... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BEGIN TO IMPACT OUR REGION TODAY...WITH MOSTLY CLOUDY SKIES...AND AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER. MINIMUMS RELATIVE HUMIDITIES WILL FALL INTO THE 30-40 PERCENT RANGE THIS AFTERNOON ACROSS THE UPPER HUDSON VALLEY AND SOUTHERN VT...AND 40-50 PERCENT ELSEWHERE. THE RH WILL RECOVER TO 75-90 PERCENT TONIGHT...WITH A WETTING RAINFALL DEVELOPING. THE RH WILL FALL INTO THE 60-70 PERCENT RANGE WED AFTERNOON. EAST TO SOUTHEAST WINDS WILL INCREASE TO 15-25 MPH TODAY...WITH SOME GUSTS UP TO 35 MPH POSSIBLE ACROSS HIGHER ELEVATIONS. THESE WINDS WILL DECREASE SLIGHTLY TONIGHT TO 10-20 MPH...THEN INCREASE ONCE AGAIN BY WED AFTERNOON TO 15-30 MPH. && .HYDROLOGY... THE POTENTIAL FOR HEAVY RAINFALL CONTINUES TO INCREASE...ESPECIALLY FOR THE SE CATSKILLS...MID HUDSON VALLEY AND INTO NW CT... A LARGE AND SLOW MOVING...COMPLEX STORM SYSTEM WILL BRING AN INCREASING CHANCE FOR RAIN DURING THIS AFTERNOON. PERIODS OF RAIN ARE THEN EXPECTED FOR TONIGHT THROUGH EARLY THURSDAY MORNING...WITH SOME HEAVY RAIN POSSIBLE FROM WEDNESDAY THROUGH EARLY THURSDAY...ALONG WITH A FEW RUMBLES OF THUNDER.THE RAIN COULD COME DOWN HEAVY AT TIMES LATE WEDNESDAY AFTERNOON THROUGH EARLY THURSDAY MORNING...RESULTING IN THE BULK OF THE RAINFALL. AT THIS TIME...EXPECTED RAINFALL FOR TUESDAY THROUGH THURSDAY IS 1 TO 2 INCHES...WITH 2 TO 3 INCHES ACROSS THE CENTRAL AND SOUTHEASTERN CATSKILLS...MID HUDSON VALLEY INTO THE BERKSHIRES AND ACROSS LITCHFIELD COUNTY. THIS RAINFALL WOULD RESULT IN WIDESPREAD SIGNIFICANT WITHIN BACK RISES ON RIVERS AND STREAMS...AND MINOR FLOODING OF URBAN...LOW LYING AND POOR DRAINAGE AREAS DURING PERIOD OF HEAVY RAINFALL. BASED ON CURRENT FORECASTS...SOME OF THE RIVER POINTS IN THE HOUSATONIC BASIN WOULD REACH ACTION STAGE WITH CLOSE TO MINOR FLOOD POSSIBLE IN THE LOWER PORTION OF THE BASIN AT GAYLORDSVILLE AND STEVENSON DAM. THERE IS STILL UNCERTAINTY IN THE FORECAST SINCE WE ARE DEALING WITH A CUT OFF LOW PRESSURE SYSTEM. SMALL CHANGES IN THE FORECASTED RAINFALL COULD LEAD TO FLOODING ISSUES. AS OF NOW...THE HEAVIEST AXIS OF MOST PERSISTENT RAINFALL LOOKS TO BE JUST SOUTHWEST OF OUR REGION. HOWEVER...SHOULD FUTURE FORECASTS SUGGEST THAT THIS AXIS SHIFTS FURTHER NORTH AND EAST...THEN A FLOOD WATCH MAY HAVE TO BE ISSUED FOR PORTIONS OF THE FORECAST AREA. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/FRUGIS/KL NEAR TERM...KL SHORT TERM...KL LONG TERM...FRUGIS/11 AVIATION...11 FIRE WEATHER...IAA/KL HYDROLOGY...IAA/KL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1122 AM EDT TUE APR 29 2014 ...STRONG TO SEVERE STORMS LOOKING TO BUILD BACK INTO WESTERN PORTIONS OF AREA LATE AFTERNOON INTO EVENING... .UPDATE... MADE SIGNIFICANT UPDATES TO POP AND WEATHER TRENDS TODAY AS MAJORITY OF GUIDANCE AND OBS TRENDS SUGGEST LULL IN ACTIVITY UNTIL AFTER ABOUT 21Z THIS AFTERNOON. SOME UPSTREAM CONVECTION ALONG THE FLORIDA PANHANDLE MAY ALSO CONTRIBUTE TO THE BREAK IN ACTION. OF THE SUITE OF HI-RES SOLUTIONS...THE RUC HAS VERIFIED THE BEST INITIALLY AND TRIGGERS DEVELOPMENT ALONG THE MISSISSIPPI/ALABAMA BORDER WHICH SEEMS LEGIT GIVEN AN AREA OF SOLAR SHELTERING OCCURRING WITH LINGERING MORNING CLOUD COVERAGE. STORMS SHOULD MAKE THERE WAY INTO THE WESTERN PORTIONS OF THE CWA NEAR 23/00Z. STILL DAMAGING WIND AND TORNADO THREAT GIVEN INSTABILITY AND SHEAR PARAMETERS WORKING INTO NORTHWEST HALF OF CWA THOUGH UNCERTAINTY OF IT PROPAGATING INTO EAST CENTRAL GA. ALSO LATEST HPC QPF LOOKS REASONABLE SO HAVE UPDATED TOTALS TO GET AN ADDITIONAL 2-3 INCHES THROUGH WEDNESDAY. PREVIOUS DISCUSSION FOLLOWS... && .PREV DISCUSSION... /ISSUED 745 AM EDT TUE APR 29 2014/ .SHORT TERM /TODAY THROUGH WEDNESDAY/... BROAD CLOSED UPPER LOW OVER THE MID WEST WILL PERSIST THROUGH THE PERIOD. THE CYCLONIC UPPER FLOW WILL SEND SEVERAL SHORT WAVES THROUGH THE SOUTHEAST STATES THROUGH WEDNESDAY WITH PERIODS OF SHOWERS AND THUNDERSTORMS. TIMING OF THESE WAVES IS DIFFICULT...AND THERE ARE ALSO UNCERTAINTIES CONCERNING THE EVOLUTION OF CURRENT CONVECTION. THERE MAY BE A BRIEF BREAK AFTER THIS MORNINGS ACTIVITY WITH REDEVELOPMENT EXPECTED THIS AFTERNOON AND EVENING. HAVE GENERALLY KEPT POPS HIGH ACROSS MUCH OF THE CWA. THE SURFACE FRONT MAY DRIFT INTO NORTHWEST GA ON WEDNESDAY. HAVE SHOWN SOME DECREASE IN POPS ACROSS THE NORTHWEST ON WEDNESDAY...BUT ONLY A FEW DEGREES OFF THE AFTERNOON MAX TEMPERATURES. 41 && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... COLD FRONT EXPECTED TO EXIT THE AREA LATE WEDNESDAY NIGHT..ENDING THUNDERSTORM CHANCES. THE DIFFICULTY THEN BECOMES THE SW UPPER FLOW CONTINUES THRU ABOUT 12Z SAT WITH POTENTIAL FOR MAINLY LIGHT SHOWER CHANCES OVER MAINLY CENTRAL GA AS SOME LESSER MOISTURE MOVES THROUGH THE FLOW. AFTER 12Z SAT THE UPPER TROUGH MOVES ACROSS THE AREA WITH A DRY FORECAST FOR THE REST OF THE LONG TERM. TEMPERATURES WILL TRANSITION TO BELOW NORMAL AT THE START OF THE LONG TERM THEN BACK TO NORMAL ON SATURDAY AND THEN ABOVE NORMAL THE REST OF THE LONG TERM. BDL && .HYDROLOGY... A FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY NIGHT HIGHLIGHTING THE IMPACTS OF 2 TO 4 INCHES IN NORTH GA TO 1 TO 2 INCHES CENTRAL GA. ISOLATED HIGHER AMOUNTS WILL BE POSSIBLE. THESE RAINFALL AMOUNTS SHOULD CAUSE WIDESPREAD MINOR AREAL AND RIVER FLOODING. THE GREATEST FLASH FLOOD THREAT WILL BE IN NORTH GA IN URBAN AREAS AND IN ROLLING HILLS OR MOUNTAINOUS TERRAINS WITH HIGH RAINFALL RATES. MOST STREAMFLOWS ARE RUNNING NEAR NORMAL NORTH GA TO WELL ABOVE NORMAL CENTRAL GA. && .AVIATION... 12Z UPDATE... THUNDERSTORMS HAVE DIMINISHED IN INTENSITY AND HAVE REMOVED MOST COUNTIES FROM THE TORNADO WATCH. EXPECT SOME SHOWER/THUNDERSTORM ACTIVITY THROUGH THE MORNING BUT NOT SEVERE. SHOULD BE SOME REDEVELOPMENT THIS AFTERNOON AND EVENING WITH DAYTIME HEATING AND A FEW SEVERE POSSIBLE THEN. CEILINGS AND VISIBILITY SHOULD BE MOSTLY VFR BUT EXPECT MVFR OR IFR WITH RAIN. WINDS WILL VARY AROUND 180 TODAY 10 TO 15KT WITH SOME GUSTS TO 25 TO 30KT ESPECIALLY IN STORMS. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS 41 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 66 79 55 73 / 80 90 60 10 ATLANTA 66 75 54 70 / 80 90 20 10 BLAIRSVILLE 61 70 49 66 / 90 90 20 10 CARTERSVILLE 64 74 50 70 / 90 90 20 10 COLUMBUS 67 78 57 73 / 70 90 40 10 GAINESVILLE 65 73 53 69 / 90 90 20 10 MACON 69 81 58 74 / 60 80 60 30 ROME 64 74 50 69 / 90 80 20 10 PEACHTREE CITY 67 75 53 71 / 80 90 20 10 VIDALIA 69 83 63 75 / 50 60 70 40 && .FFC WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR THE FOLLOWING ZONES: BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY... BUTTS...CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA... CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...CRISP... DADE...DAWSON...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL... FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...GLASCOCK... GORDON...GREENE...GWINNETT...HALL...HANCOCK...HARALSON... HARRIS...HEARD...HENRY...HOUSTON...JACKSON...JASPER... JEFFERSON...JOHNSON...JONES...LAMAR...LAURENS...LUMPKIN... MACON...MADISON...MARION...MERIWETHER...MONROE...MONTGOMERY... MORGAN...MURRAY...MUSCOGEE...NEWTON...NORTH FULTON...OCONEE... OGLETHORPE...PAULDING...PEACH...PICKENS...PIKE...POLK... PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING... STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR... TOOMBS...TOWNS...TREUTLEN...TROUP...TWIGGS...UNION...UPSON... WALKER...WALTON...WARREN...WASHINGTON...WEBSTER...WHEELER... WHITE...WHITFIELD...WILCOX...WILKES...WILKINSON. && $$ SHORT TERM...41/BAKER LONG TERM...BDL AVIATION...41
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1156 AM EDT TUE APR 29 2014 .UPDATE... ISSUED AT 1153 AM EDT TUE APR 29 2014 ...ADVISORY ISSUED FOR NEAR TERM TRAVEL HAZARDS... BASED ON NUMEROUS REPORTS OF ACCIDENTS AND WEBCAMS CONFIRMING THAT SNOW IS ACCUMULATING ON ROADWAYS OVER THE HIGHER TERRAIN /~1500 FT/ WILL ISSUE A SHORT FUSED WINTER WEATHER ADVISORY TO COVER THE TRAVEL HAZARD THROUGH EARLY AFTERNOON. THE IMPACTS WILL BE COMPLETELY TIED TO PRECIPITATION RATES...AND WITH THE BACK EDGE OF RETURNS ALREADY PULLING NORTH THROUGH MENOMINEE COUNTY...THIS PROVIDED A PRETTY SHORT WINDOW FOR ACCUMULATING SNOW. STILL 2-4" IS LIKELY OVER THE HIGH TERRAIN BEFORE PRECIPITATION TAPERS TO DRIZZLE. UPDATE ISSUED AT 954 AM EDT TUE APR 29 2014 ...QUICK BURST OF SNOW THIS MORNING AS PRECIPITATION ARRIVES... BASED ON MORNING SPOTTER REPORTS AND AREA WEBCAMS...HAVE BOOSTED SNOW TOTALS SLIGHTLY AS PRECIPITATION IS ARRIVING AS A BURST OF SNOW FOR AREAS FROM MARQUETTE SOUTH AND WEST. DUAL POL VARIABLES FROM THE KMQT-88D SUGGEST A GROWING SURFACE-BASED WARM LAYER AT MQT...AND DO EXPECT A PRETTY STEADY TRANSITION TO RAIN FROM EAST TO WEST DURING THE MORNING...WITH THIS CHANGEOVER NOT REACHING AREAS FROM ONTONAGON TO IRONWOOD UNTIL LATE AFTERNOON...BY WHICH TIME THE HEAVIEST BAND OF PRECIPITATION WILL BE BEGINNING TO LIFT NORTH OF THE REGION. ISSUED A SPS TO HANDLE QUICK BURST OF SNOW...AND MAY DO SO ONCE MORE FOR WESTERN ZONES AS PRECIPITATION ARRIVES HERE. DID SLOW PRECIPITATION ARRIVAL JUST A TAD BASED ON MORNING RADAR EVOLUTION...BUT NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 520 AM EDT TUE APR 29 2014 WV IMAGERY AND RUC ANALYSIS REVEALS REX BLOCK PATTERN OVER THE CENTRAL PORTION OF NORTH AMERICA WITH A HIGH OVER HUDSON BAY AND AN OCCLUDING CLOSED LOW OVER THE IOWA/MISSOURI BORDER. AT THE SFC...A FEW SITES WERE REPORTING GUSTY EAST TO NORTHEAST WINDS AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER NW MISSOURI. BOTH KCMX AND KMNM WERE REPORTING WIND GUSTS TO NEAR 40 MPH AT TIMES EARLY THIS MORNING. A BAND OF RAIN OVER NORTHERN LAKE MI AND SE UPPER MI SUPPORTED BY 295K-300K ISENTROPIC ASCENT WAS MAKING VERY SLOW NORTHWARD PROGRESS AS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 750 MB) TO THE NORTH AND EAST...PER 00Z APX SOUNDING. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...INCREASING 295K ISENTROPIC ASCENT WILL FINALLY OVERCOME LOW-LVL DRY AIR AND ALLOW PCPN TO SPREAD FROM SCNTRL/SE CWA NORTH AND WEST ACROSS THE REST OF WEST AND CENTRAL UPPER MI LATER THIS MORNING AND AFTERNOON. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE HEAVIER PCPN WILL COINCIDE WITH TROWAL REGION NORTH OF THE MID/UPPER LOW AS NOTED ON MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TONIGHT. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS THERE. SOME UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET- BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE WRN INTERIOR THIS MORNING...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE FAR WEST TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE SNOW ACCUMULATION TO AN INCH OR MAYBE TWO TOWARD KIWD WITH MOST ACCUMULATION ON GRASSY OR SNOW COVERED AREAS. WITH MODELS SHOWING SHORTWAVE AND ASSOC TROWAL REGION LIFTING NORTH AND WEST OF THE FCST AREA TONIGHT ALONG WITH CORRESPONDING WEAKENING OF ISENTROPIC ASCENT AND TRANSITION TO MID-LVL Q-VECT DIVERGENCE... LOOK FOR HEAVIER PCPN TO TAPER OFF AND BECOME MORE LIGHT AND SCATTERED WITH MOST LOCATIONS SEEING BTWN .1 TO .2 INCH. WITH WARMING LOW-LVLS AS NOTED ON SOUNDINGS AND RISING 1000-850 MB THICKNESSES WOULD EXPECT PTYPE MOSTLY RAIN TONIGHT. AREA RIVERS AND STREAMS WILL NEED TO BE MONITORED CLOSELY OVER THE NEXT SEVERAL DAYS AS RUNOFF FROM PCPN AND SNOWMELT WILL LEAD TO RISING RIVER LEVELS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 715 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL QUICKLY LOWER TO MVFR AND THEN LIFR AS RAIN MOVES IN FM THE SE THIS MORNING INTO EARLY AFTERNOON. RAIN WILL MIX WITH OR CHANGE TO ALL SNOW AT KIWD TODAY AN COULD RESTRICT VSBYS TO IFR. UPSLOPE FOG COULD ALSO DEVELOP AT KIWD AND KSAW AS RAIN AND WARMER DEWPOINTS MOVE OVER COLDER LAKE SUPERIOR. ENE WINDS WILL GUST AOA 30 KNOTS AT KCMX THIS MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT TUE APR 29 2014 AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER CENTRAL PLAINS AND THE STRONG HIGH OVER HUDSON BAY EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE EVENING. THESE WINDS WILL ALSO BE ENHANCED BY CHANNELING BETWEEN THE KEWEENAW PENINSULA AND ISLE ROYALE. A FEW ENE GALE FORCE GUSTS TO 35 KNOTS ARE ALSO POSSIBLE OVER CENTRAL LAKE SUPERIOR MAINLY THIS MORNING BUT SUSTAINED GALES ARE NOT EXPECTED SO WATCH HEADLINE HAS BEEN DROPPED. THE WINDS WILL DIMINISH THIS EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE && .MQT WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR MIZ002-004-005-009>011-084. LS...GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263-264. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ221-248- 250. && $$ UPDATE...ARNOTT/APX SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS HYDROLOGY...TITUS MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1001 AM EDT TUE APR 29 2014 .UPDATE... ISSUED AT 954 AM EDT TUE APR 29 2014 ...QUICK BURST OF SNOW THIS MORNING AS PRECIPITATON ARRIVES... BASED ON MORNING SPOTTER REPORTS AND AREA WEBCAMS...HAVE BOOSTED SNOW TOTALS SLIGHTLY AS PRECIPITATION IS ARRIVING AS A BURST OF SNOW FOR AREAS FROM MARQUETTE SOUTH AND WEST. DUAL POL VARIABLES FROM THE KMQT-88D SUGGEST A GROWING SURFACE-BASED WARM LAYER AT MQT...AND DO EXPECT A PRETTY STEADY TRANSITION TO RAIN FROM EAST TO WEST DURING THE MORNING...WITH THIS CHANGEOVER NOT REACHING AREAS FROM ONTONAGON TO IRONWOOD UNTIL LATE AFTERNOON...BY WHICH TIME THE HEAVIEST BAND OF PRECIPITATION WILL BE BEGINNING TO LIFT NORTH OF THE REGION. ISSUED A SPS TO HANDLE QUICK BURST OF SNOW...AND MAY DO SO ONCE MORE FOR WESTERN ZONES AS PRECIPITATION ARRIVES HERE. DID SLOW PRECIPITATION ARRIVAL JUST A TAD BASED ON MORNING RADAR EVOLUTION...BUT NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 520 AM EDT TUE APR 29 2014 WV IMAGERY AND RUC ANALYSIS REVEALS REX BLOCK PATTERN OVER THE CENTRAL PORTION OF NORTH AMERICA WITH A HIGH OVER HUDSON BAY AND AN OCCLUDING CLOSED LOW OVER THE IOWA/MISSOURI BORDER. AT THE SFC...A FEW SITES WERE REPORTING GUSTY EAST TO NORTHEAST WINDS AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER NW MISSOURI. BOTH KCMX AND KMNM WERE REPORTING WIND GUSTS TO NEAR 40 MPH AT TIMES EARLY THIS MORNING. A BAND OF RAIN OVER NORTHERN LAKE MI AND SE UPPER MI SUPPORTED BY 295K-300K ISENTROPIC ASCENT WAS MAKING VERY SLOW NORTHWARD PROGRESS AS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 750 MB) TO THE NORTH AND EAST...PER 00Z APX SOUNDING. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...INCREASING 295K ISENTROPIC ASCENT WILL FINALLY OVERCOME LOW-LVL DRY AIR AND ALLOW PCPN TO SPREAD FROM SCNTRL/SE CWA NORTH AND WEST ACROSS THE REST OF WEST AND CENTRAL UPPER MI LATER THIS MORNING AND AFTERNOON. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE HEAVIER PCPN WILL COINCIDE WITH TROWAL REGION NORTH OF THE MID/UPPER LOW AS NOTED ON MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TONIGHT. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS THERE. SOME UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET- BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE WRN INTERIOR THIS MORNING...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE FAR WEST TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE SNOW ACCUMULATION TO AN INCH OR MAYBE TWO TOWARD KIWD WITH MOST ACCUMULATION ON GRASSY OR SNOW COVERED AREAS. WITH MODELS SHOWING SHORTWAVE AND ASSOC TROWAL REGION LIFTING NORTH AND WEST OF THE FCST AREA TONIGHT ALONG WITH CORRESPONDING WEAKENING OF ISENTROPIC ASCENT AND TRANSITION TO MID-LVL Q-VECT DIVERGENCE... LOOK FOR HEAVIER PCPN TO TAPER OFF AND BECOME MORE LIGHT AND SCATTERED WITH MOST LOCATIONS SEEING BTWN .1 TO .2 INCH. WITH WARMING LOW-LVLS AS NOTED ON SOUNDINGS AND RISING 1000-850 MB THICKNESSES WOULD EXPECT PTYPE MOSTLY RAIN TONIGHT. AREA RIVERS AND STREAMS WILL NEED TO BE MONITORED CLOSELY OVER THE NEXT SEVERAL DAYS AS RUNOFF FROM PCPN AND SNOWMELT WILL LEAD TO RISING RIVER LEVELS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 715 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL QUICKLY LOWER TO MVFR AND THEN LIFR AS RAIN MOVES IN FM THE SE THIS MORNING INTO EARLY AFTERNOON. RAIN WILL MIX WITH OR CHANGE TO ALL SNOW AT KIWD TODAY AN COULD RESTRICT VSBYS TO IFR. UPSLOPE FOG COULD ALSO DEVELOP AT KIWD AND KSAW AS RAIN AND WARMER DEWPOINTS MOVE OVER COLDER LAKE SUPERIOR. ENE WINDS WILL GUST AOA 30 KNOTS AT KCMX THIS MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT TUE APR 29 2014 AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER CENTRAL PLAINS AND THE STRONG HIGH OVER HUDSON BAY EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE EVENING. THESE WINDS WILL ALSO BE ENHANCED BY CHANNELING BETWEEN THE KEWEENAW PENINSULA AND ISLE ROYALE. A FEW ENE GALE FORCE GUSTS TO 35 KNOTS ARE ALSO POSSIBLE OVER CENTRAL LAKE SUPERIOR MAINLY THIS MORNING BUT SUSTAINED GALES ARE NOT EXPECTED SO WATCH HEADLINE HAS BEEN DROPPED. THE WINDS WILL DIMINISH THIS EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE && .MQT WATCHES/WARNINGS/ADVISORIES... MI...NONE. LS...GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263-264. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ221-248- 250. && $$ UPDATE...ARNOTT/APX SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS HYDROLOGY...TITUS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
727 AM EDT TUE APR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 520 AM EDT TUE APR 29 2014 WV IMAGERY AND RUC ANALYSIS REVEALS REX BLOCK PATTERN OVER THE CENTRAL PORTION OF NORTH AMERICA WITH A HIGH OVER HUDSON BAY AND AN OCCLUDING CLOSED LOW OVER THE IOWA/MISSOURI BORDER. AT THE SFC...A FEW SITES WERE REPORTING GUSTY EAST TO NORTHEAST WINDS AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER NW MISSOURI. BOTH KCMX AND KMNM WERE REPORTING WIND GUSTS TO NEAR 40 MPH AT TIMES EARLY THIS MORNING. A BAND OF RAIN OVER NORTHERN LAKE MI AND SE UPPER MI SUPPORTED BY 295K-300K ISENTROPIC ASCENT WAS MAKING VERY SLOW NORTHWARD PROGRESS AS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 750 MB) TO THE NORTH AND EAST...PER 00Z APX SOUNDING. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...INCREASING 295K ISENTROPIC ASCENT WILL FINALLY OVERCOME LOW-LVL DRY AIR AND ALLOW PCPN TO SPREAD FROM SCNTRL/SE CWA NORTH AND WEST ACROSS THE REST OF WEST AND CENTRAL UPPER MI LATER THIS MORNING AND AFTERNOON. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE HEAVIER PCPN WILL COINCIDE WITH TROWAL REGION NORTH OF THE MID/UPPER LOW AS NOTED ON MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TONIGHT. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS THERE. SOME UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET- BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE WRN INTERIOR THIS MORNING...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE FAR WEST TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE SNOW ACCUMULATION TO AN INCH OR MAYBE TWO TOWARD KIWD WITH MOST ACCUMULATION ON GRASSY OR SNOW COVERED AREAS. WITH MODELS SHOWING SHORTWAVE AND ASSOC TROWAL REGION LIFTING NORTH AND WEST OF THE FCST AREA TONIGHT ALONG WITH CORRESPONDING WEAKENING OF ISENTROPIC ASCENT AND TRANSITION TO MID-LVL Q-VECT DIVERGENCE... LOOK FOR HEAVIER PCPN TO TAPER OFF AND BECOME MORE LIGHT AND SCATTERED WITH MOST LOCATIONS SEEING BTWN .1 TO .2 INCH. WITH WARMING LOW-LVLS AS NOTED ON SOUNDINGS AND RISING 1000-850 MB THICKNESSES WOULD EXPECT PTYPE MOSTLY RAIN TONIGHT. AREA RIVERS AND STREAMS WILL NEED TO BE MONITORED CLOSELY OVER THE NEXT SEVERAL DAYS AS RUNOFF FROM PCPN AND SNOWMELT WILL LEAD TO RISING RIVER LEVELS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER TEMPS IF MODELS VERIFY WELL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 715 AM EDT TUE APR 29 2014 VFR CONDITIONS WILL QUICKLY LOWER TO MVFR AND THEN LIFR AS RAIN MOVES IN FM THE SE THIS MORNING INTO EARLY AFTERNOON. RAIN WILL MIX WITH OR CHANGE TO ALL SNOW AT KIWD TODAY AN COULD RESTRICT VSBYS TO IFR. UPSLOPE FOG COULD ALSO DEVELOP AT KIWD AND KSAW AS RAIN AND WARMER DEWPOINTS MOVE OVER COLDER LAKE SUPERIOR. ENE WINDS WILL GUST AOA 30 KNOTS AT KCMX THIS MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT TUE APR 29 2014 AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER CENTRAL PLAINS AND THE STRONG HIGH OVER HUDSON BAY EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE EVENING. THESE WINDS WILL ALSO BE ENHANCED BY CHANNELING BETWEEN THE KEWEENAW PENINSULA AND ISLE ROYALE. A FEW ENE GALE FORCE GUSTS TO 35 KNOTS ARE ALSO POSSIBLE OVER CENTRAL LAKE SUPERIOR MAINLY THIS MORNING BUT SUSTAINED GALES ARE NOT EXPECTED SO WATCH HEADLINE HAS BEEN DROPPED. THE WINDS WILL DIMINISH THIS EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED INTO SAT AS THE LOW FILLS AND REMAINS NEAR UPPER MICHIGAN. && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE SIGNIFICANT ICE REMAINS AT THE SHORE OR JUST OFFSHORE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS MARINE...VOSS HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
ISSUED BY NATIONAL WEATHER SERVICE ALBANY NY 1053 AM EDT TUE APR 29 2014 .SYNOPSIS... LOW PRESSURE WILL SPIN OVER THE NORTHERN OHIO VALLEY AND THE GREAT LAKES REGION FOR THE NEXT FEW DAYS. THIS WILL KEEP A STEADY STREAM OF MODERATE RAIN SHOWERS MOVING OVER OUR REGION THROUGH EARLY THURSDAY. WINDS WILL BECOME GUSTY ON WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1053 AM EDT...LOW STRATUS CLOUDS IN PLACE WITH E-SE FLOW ACROSS THE AREA. RAIN ALSO DEVELOPING FROM WEST TO EAST DUE TO ISENTROPIC LIFT ON THE 295K SURFACE. CURRENT RADAR AND OBSERVATIONS INDICATE RAIN IS STARTING ACROSS THE FINGER LAKES AND SOUTHERN TIER WEST OF BGM IN NEW YORK...AND JUST ABOUT ENTERING NORTHEAST PA ACROSS BRADFORD/LUZERNE COUNTIES. RAIN WILL BE MAINLY LIGHT TODAY...AS LOW LEVELS WILL TAKE TIME FOR COMPLETE SATURATION TO OCCUR. WILL GRADUALLY INCREASE POPS FROM WEST TO EAST THROUGH THIS AFTERNOON. CURRENT HRRR SEEMS TO HAVE A GOOD HANDLE ON THE PRECIP. TEMPERATURES WILL BE COOL DUE TO EXTENSIVE CLOUD COVER AND DEVELOPING RAINFALL. HIGH TEMPERATURES WILL LIKELY OCCUR EARLY THIS AFTERNOON FOR CENTRAL/EASTERN ZONE...AS COOLING WILL TAKE PLACE ONCE RAIN COMMENCES. HIGHS ONLY EXPECTED TO BE IN THE 50S FOR MOST AREAS...WITH UPPER 40S OVER THE HIGHER TERRAIN. GUSTY SOUTHEAST WINDS WILL CONTINUE THROUGH THE AFTERNOON AND ALSO TONIGHT...AS A LOW LEVEL JET INCREASES. MAX GUSTS EXPECTED TO BE AROUND 35 TO 40 MPH...WITH POTENTIALLY STRONGER GUSTS ON WEDNESDAY AS THE FLOW STRENGTHENS FURTHER. TOWARDS THIS EVENING...A BRIEF BREAK IN THE RAINFALL WILL BE POSSIBLE FOR WESTERN/CENTRAL ZONES...AS THE FIRST WAVE OF LIFT MOVES EAST. HOWEVER...ADDITIONAL MOISTURE/LIFT IS EXPECTED TO RE- DEVELOP FROM SW TO NE ACROSS THE REGION LATER TONIGHT. RAINFALL AMOUNTS THROUGH TONIGHT WILL BE AROUND ONE HALF TO ONE INCH...WITH THE GREATEST AMOUNTS ACROSS THE SOUTHEAST HALF OF THE AREA...ESPECIALLY FROM AROUND SCRANTON/WILKES-BARRE NORTHEASTWARD INTO THE CATSKILLS. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... THE ENTIRE PERIOD LOOKS UNSETTLED AND SHOWERY. THE STEADIEST PRECIP WILL BE FROM THIS AFTERNOON THROUGH WEDNESDAY NIGHT, AS LOW WRAPS UP OVER THE OHIO VALLEY AND GREAT LAKES. THE MOST INTERESTING PERIOD APPEARS TO BE EARLY WEDNESDAY THROUGH WEDNESDAY AFTERNOON, WHEN 60-70 KNOT JET BETWEEN 900-850MB RIPS UP THE CENTRAL SOUTHERN TIER TOWARD THE WESTERN MOHAWK VALLEY. ISENTROPIC LIFT ALONG AND AHEAD OF THE JET WILL ENHANCE POTENTIAL FOR MODERATE RAIN (WITH BRIEF PERIODS OF HEAVY DOWNPOURS POSSIBLE). THIS SAME JET COULD CAUSE ADVISORY CRITERIA WINDS, AND WE ARE CLOSELY MONITORING THE POTENTIAL. AT THIS POINT, THE STRENGTH OF THE JET BELOW 850MB MEETS THE CRITERIA FOR ADVISORY WIND GUSTS IN SE FLOW PER LOCAL RESEARCH STUDY. HOWEVER...LOCAL RESEARCH ALSO INDICATES THESE EVENTS ARE GENERALLY ASSOCIATED WITH VERY STRONG CYCLONES OVER THE GREAT LAKES, AND SHARPER 500H TROFS THAN WE ARE FORECASTING. TOTAL RAINFALL THROUGH EARLY THURSDAY WILL RANGE FROM 1.50 TO 2.00 INCHES OVER THE NORTHERN FA, AND 2.00 TO 2.70 INCHES OVER NERN PA. THIS SOAKING RAIN IS MUCH NEEDED GIVEN THE RECENT DRY SPELL. THE QPF WILL CAUSE SIGNIFICANT RISES, BUT THE DURATION MAY BE STRETCHED OUT ENOUGH TO AVOID SIGNIFICANT ISSUES. WILL HOLD OFF ON WATCH AT THIS JUNCTURE, AS WE STILL HAVE 24 TO 30 HOURS BEFORE THE HEAVIEST RAIN IS SCHEDULED TO ARRIVE, AND TIME TO ASSESS THE RIVER RESPONSE. ALSO...THE FIRST 12 HOURS OF THE EVENT MAY PRODUCE LESS QPF THAN ANTICIPATED AS THE EASTWARD RAIN EXTENT IS RUNNING BEHIND THE PROGS. CANNOT RULE OUT ISOLATED THUNDER ON WEDNESDAY, MAINLY OVER THE CENTRAL SOUTHERN TIER REGION WHERE THERE IS ENOUGH MID LEVEL INSTABILITY TO TAKE ADVANTAGE OF THE LIFT. && .LONG TERM /FRIDAY THROUGH MONDAY/... PATTERN WILL CONTINUE TO BE DOMINATED BY EFFECTS OF UPPER LEVEL LOW INITIALLY OVER WESTERN GREAT LAKES. IT MAY BRIEFLY OPEN UP ONLY TO RETROGRADE FARTHER WEST BY GETTING ABSORBED INTO ANOTHER DIGGING NORTHERN STREAM TROUGH IN THE CANADIAN PLAINS. WAVES WILL BE EMBEDDED IN THE BROAD CYCLONIC FLOW AROUND THE UPPER LOW...INCLUDING A LARGER JOINT SOUTHERN STREAM/NORTHERN STREAM WAVE LIFTING THROUGH SATURDAY...THUS SHOWERS ARE LIKELY THEN. THOUGH TEMPERATURES WILL KNOCK DOWN SLIGHTLY WITH THAT WAVE...CORE OF COLDER AIR WILL REMAIN WELL NORTHWEST CLOSER TO THE UPPER LOW...SO THOUGH A BIT ON THE COOL SIDE AT TIMES...OVERALL NOT FAR FROM CLIMATOLOGY. WE WILL STILL HAVE SOME CHANCE FOR SHOWERS SUNDAY AND MONDAY...AS SMALLER WAVES AND THEN A PIECE OF THE UPPER LOW ITSELF BREAK OFF AND HEAD TOWARDS OUR REGION. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... LRG CLSD LOW WILL SLOWLY MEANDER EWRD FOR THE NEXT SVRL DAYS AND PUSH RAIN INTO THE REGION. HIPRES RDGG DOWN THE EST CST WILL KEEP DRIER AIR AND VFR CONDS THRU AT LEAST MID MRNG BEFORE THE RAIN BEGINS. THEN...SLOWLY LWRG CONDS TO MVFR LATE IN THE AFTN THRU THE END OF THE PD DUE TO VSBYS AND LWR CIGS. HILLTOP STATIONS ITH AND BGM COULD SEE OCNL IFR CIGS AFT 06Z. TGT GRADIENT BETWEEN THE HI TO THE EAST AND THE MIDWEST LOW WILL PRODUCE GUSTY SE WINDS TODAY AND CNTG THRU THE TAF PD. OUTLOOK... WED AND THU...MVFR AND MAYBE IFR RESTRICTIONS IN RAIN SHOWERS. FRI/SAT...MVFR RESTRICTIONS IN SCT SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJP NEAR TERM...DJP SHORT TERM...DJP LONG TERM...MDP AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1035 AM EDT TUE APR 29 2014 .SYNOPSIS... HIGH PRESSURE WILL BRING DRY WEATHER THROUGH MOST OF TODAY. A LARGE AREA OF LOW PRESSURE ACROSS THE CENTRAL UNITED STATES WILL GRADUALLY SHIFT EASTWARD. THIS SYSTEM WILL BRING INCREASINGLY BREEZY CONDITIONS TODAY...FOLLOWED BY PERIODS OF RAIN...ESPECIALLY WEDNESDAY THROUGH THURSDAY MORNING. RAIN MAY BE HEAVY AT TIMES WEDNESDAY NIGHT. TEMPERATURES WILL REMAIN SLIGHTLY BELOW SEASONAL AVERAGES THROUGH THE END OF THE WEEK. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... AS OF 1031 AM EDT TUESDAY...DRIER AIR FROM THE EAST HAS PUSHED ACROSS MUCH OF CENTRAL AND NORTHERN VERMONT RESULTING IN MOSTLY SUNNY CONDITIONS. HAVE MADE SOME ADJUSTMENTS TO SKY COVER THROUGH THIS AFTERNOON BASED ON CURRENT CONDITIONS AND RUC RH PROFILES. MINOR ADJUSTMENTS ALSO TO TEMPERATURES...BUT OVERALL FORECAST IS ON TRACK. BROAD DEEP- LAYER LOW PRESSURE SYSTEM AFFECTING MUCH OF THE CENTRAL AND MIDWEST U.S. WILL GRADUALLY HAVE AN INCREASING INFLUENCE ON OUR WEATHER OVER THE COMING DAYS. MEANWHILE...IT LOOKS LIKE MOST OF THE FORECAST AREA WILL SEE ONE MORE DRY DAY TODAY BEFORE THE WET WEATHER ARRIVES. SURFACE RIDGE AXIS ACROSS NEW ENGLAND THIS MORNING WILL SHIFT SLOWLY EASTWARD INTO THE GULF OF MAINE BY THIS EVENING AND GENERALLY REMAIN IN CONTROL OF OUR WEATHER THROUGH THE DAYLIGHT HOURS...WITH UPSTREAM FRONTAL RAIN SLOW TO MOVE EAST DUE TO THE RIDGE ALONG THE EAST COAST. MAIN IMPACT TODAY WILL BE INCREASINGLY GUSTY EAST TO SOUTHEAST WINDS...ESPECIALLY ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS...AND ACROSS THE NORTHERN ADIRONDACKS INTO THE SAINT LAWRENCE VALLEY. SOUTHEAST WINDS OF 15-25 MPH WITH AFTERNOON GUSTS UP TO 35 MPH ARE LIKELY. EXPECT VARIABLE AMOUNTS OF CLOUD COVER THROUGH EARLY AFTERNOON...FOLLOWED BY INCREASING CLOUDS FROM SOUTHWEST TO NORTHEAST. BEST CHANCE FOR PROLONGED SUNSHINE WILL BE ACROSS CENTRAL/NRN VT. RAINFALL WILL HOLD OFF IN MOST AREAS...ALTHOUGH THERE IS A CHANCE FOR SHOWERS BY LATE IN THE DAY OVER THE SAINT LAWRENCE VALLEY AND WESTERN ADIRONDACKS. TEMPERATURES WILL BE A LITTLE MILDER THAN RECENT DAYS...BUT STILL A BIT COOL FOR LATE APRIL DUE MARINE MODIFIED AIR WORKING IN ON LOW LEVEL EASTERLY FLOW. MAX TEMPERATURES EXPECTED TO RANGE FROM 55 TO 60 DEGREES ACROSS MOST OF THE AREA THIS AFTERNOON. MARINE INFLUENCE A BIT MORE PRONOUNCED ACROSS S-CENTRAL VT...WITH TEMPS REMAINING IN THE UPR 40S TO AROUND 50 IN THE SPRINGFIELD VT AREA INTO THE SRN GREENS. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... AS OF 446 AM EDT TUESDAY...FOR TONIGHT THROUGH WEDNESDAY...700-500MB RIDGE AXIS REMAINS ACROSS CENTRAL/EASTERN NEW ENGLAND. BEST CHANCES FOR RAIN TONIGHT INTO WEDNESDAY MORNING MORNING WILL BE ACROSS NORTHERN NEW YORK...THEN AS RIDGE AXIS MOVES SLOWLY EAST...MORE WIDESPREAD RAINFALL MOVES INTO VERMONT WEDNESDAY AFTERNOON. MARINE MODIFIED AIR MASS REMAINS OVER THE REGION AND WE WILL SEE A CONTINUATION OF GUSTY SOUTHEAST WINDS AT 15 TO 25 MPH WITH GUSTS 35 MPH...ESPECIALLY DURING WEDNESDAY. MIN TEMPS TONIGHT IN THE MID 30S TO LOWER 40S...WITH HIGHS WEDNESDAY IN THE 40S TO AROUND 50. THE MOST WIDESPREAD AND SIGNIFICANT RAINFALL WITH THIS EVENT STILL SHAPING UP TO OCCUR WEDNESDAY NIGHT. FRONTAL RAIN BAND ASSOCIATED WITH APPROACHING OCCLUSION FROM THE SOUTHWEST WILL FINALLY SPREAD STEADY RAIN ACROSS THE ENTIRE FORECAST AREA. STRONG SOUTHERLY 850 MB JET MOVES ACROSS THE AREA WEDNESDAY NIGHT...WHEN BEST FORCING AND LIFT WILL OCCUR. THIS COUPLED WITH PRECIPITABLE WATER VALUES OF AROUND 1.25 INCHES ALL SUPPORT POSSIBILITY OF MODERATE TO EVEN HEAVY RAINFALL AT TIMES. GUSTY SOUTHEAST WINDS SHOULD GRADUALLY DIMINISH OVERNIGHT...BUT WILL STILL SEE SOME OROGRAPHIC INFLUENCES AFFECTING PRECIPITATION AMOUNTS...WITH SOME ENHANCEMENT ACROSS THE EAST FACING SLOPES OF THE GREEN MOUNTAINS AND THE NORTHERN ADIRONDACKS. RAIN WILL TAPER OFF TO SHOWERS DURING THURSDAY AS OCCLUDED FRONT MAKES ITS EASTWARD ACROSS FORECAST AREA...WHILE TRAILING MID LEVEL SHORTWAVE MOVES ACROSS THE AREA LATER IN THE DAY. HIGH POPS PREFERRED THROUGH MUCH OF THE DAY. TEMPS MILDER WITH HIGHS AROUND 60. A BIT COOLER IN EASTERN VERMONT WHERE FRONTAL PASSAGE NOT EXPECTED TILL LATE IN THE DAY. AS FOR STORM TOTAL RAINFALL...LOOKING AT 1.25-1.5" ACROSS SOUTH-CENTRAL VERMONT AND FOR THE NORTHERN ADIRONDACKS AND ST. LAWRENCE VALLEY. GENERALLY 0.75-1" IN THE CHAMPLAIN VALLEY AND NORTHEAST KINGDOM WHERE AMOUNTS LOWER DUE SOME SHADOWING. HYDROLOGICALLY...RIVERS HAVE RECEDED TO NEAR BASE LEVELS BUT WILL NEED TO MONITOR AUSABLE FORKS AND OTTER CREEK AT CENTER RUTLAND IF RAINFALL EXCEEDS CURRENT EXPECATATIONS. BASED ON CURRENT FORECAST...ALL RIVERS WILL REMAIN WITHIN BANKFULL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 351 AM EDT TUESDAY...VERY LITTLE CHANGE FROM PREVIOUS FORECAST THINKING AS THE REGION WILL LARGELY BE DOMINATED BY A SLOW MOVING CLOSED UPPER LEVEL LOW AND TROUGH THROUGH MUCH OF THE EXTENDED PERIOD. THE RESULT WILL BE GENERALLY CLOUDY AND COOL CONDITIONS WITH ON AND OFF CHANCES FOR PRECIPITATION...MAINLY DURING THE DAYLIGHT HOURS. TEMPS WILL RUN SLIGHTLY BELOW NORMAL WITH HIGHS IN THE 50S...AND LOWS IN THE MID 30S TO LOW 40S. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... THROUGH 12Z WEDNESDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD AS THE REGION REMAINS IN-BETWEEN UPPER LEVEL LOW PRESSURE SYSTEMS TO OUR EAST AND WEST TODAY. SOUTHEAST FLOW WILL BRING IN OCCASIONAL MVFR TO KRUT/KMPV EARLY THIS MORNING...BUT THE TREND WILL BE TOWARDS ALL SITES BEING VFR UNDER MID CLOUDS BY MID-DAY AS LOW LEVELS DRY OUT. SOUTHEAST FLOW STRENGTHENS THROUGH THE DAY AS WELL WITH ANY SUNSHINE INCREASING MIXING AND EXPECT TO SEE GUSTS OF 20-30KTS ACROSS THE REGION. LATE TODAY MID CLOUDS THICKEN IN ADVANCE OF PRECIP MOVING INTO NORTHERN NEW YORK THIS EVENING...THOUGH THOUGH CONDITIONS WILL REMAIN LARGELY VFR THROUGH 12Z EXCEPT FOR KRUT AND KMPV WHERE MVFR CIGS WILL RETURN OVERNIGHT. OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY... 12Z WED THRU 00Z THU...VFR WITH OCCASIONAL MVFR IN SHOWERS. 00Z THU THRU 00Z FRI...MVFR WITH OCCASIONAL IFR IN RAIN. 00Z FRI THRU 00Z SUN...MAINLY MVFR WITH OCCASIONAL VFR IN SCATTERED SHOWERS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...RJS NEAR TERM...BANACOS/RJS SHORT TERM...RJS LONG TERM...LAHIFF AVIATION...LAHIFF
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
631 AM CDT TUE APR 29 2014 .DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS. && .AVIATION...LOW CLOUD SATELLITE IMAGE SHOWS THE LOW STRATUS LAYER HAS MOVED INLAND TO EAST OF HEBBRONVILLE TO NORTHWEST OF BEEVILLE. NON-UNIFORM CATEGORIES EXIST WITHIN THIS CLOUD LAYER...SOME AREAS ALONG THE COAST THEN UP TO VICTORIA HAVE LOW MVFR CEILINGS AND MVFR VSBYS. WHILE AREAS ON THE WESTERN EDGE OF THE CLOUD LAYER FROM ALICE TO BEEVILLE HAVE VLIFR CEILINGS/VSBYS WITH PATCHY DENSE FOG. EXPECT THIS CLOUD LAYER WILL LINGER UNTIL AROUND 14Z. WINDS WILL BE TURNING TO THE NORTHWEST WITH AN IMPROVEMENT TO VFR BETWEEN 14-15Z. WINDS WILL STEADILY INCREASE TO THE NORTH BY 18Z WITH GUSTS TO NEAR 25 KNOTS FOR THIS AFTERNOON WITH CLEAR SKIES/VFR CONDITIONS. WINDS WILL DIMINISH BY THIS EVENING WITH VFR CONDITIONS TONIGHT. && .PREV DISCUSSION... /ISSUED 423 AM CDT TUE APR 29 2014/ SHORT TERM (TODAY THROUGH WEDNESDAY)...MARINE LAYER WITH LOW STRATUS AND FOG HAS MOVED INTO THE COASTAL PLAINS EARLY THIS MORNING. A TROUGH AXIS AHEAD OF THE FRONT...OVER THE HILL COUNTRY EARLY THIS MORNING...WILL MOVE TOWARD THE COAST BY 15Z WITH THE FRONT MOVING IN LATER THIS MORNING. HIGHER NORTH WINDS BEHIND FRONT SINCE IT IS HARD TO SAY COLD FRONT WHEN THE TEMPERATURES ARE STILL EXPECTED TO REACH THE 90S TODAY. WENT WITH HRRR MODEL DEPICTING MUCH LOWER DEWPOINT TEMPS REACHING THE COASTAL PLAINS THIS AFTERNOON. COOLER AND DRIER AIR WILL REACH AREA FOR TONIGHT WITH LOWS MAINLY IN THE 50S. READINGS WILL FINALLY BE CLOSER TO NORMAL FOR WEDNESDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE AREA. MARINE (TODAY THROUGH WEDNESDAY)...WIDESPREAD FOG HAS MOVED INTO THE NORTHWEST GULF EARLY THIS MORNING. THIS FOG IS MIXED WITH SMOKE FROM CENTRAL AMERICA/YUCATAN PENINSULA AND VISIBILITIES ARE VERY POOR OVER THE WATERS. ISSUED DENSE FOG ADVISORY EARLIER AND KEPT EXPIRATION TIME AT 14Z. EXPECTING WINDS TO SHIFT TO SOUTHWEST WITH VISIBILITIES SLOWLY IMPROVING BEFORE MAIN FRONTAL WIND SHIFT MOVES INTO THE WATERS BY 18Z. WINDS WILL SLOWLY INCREASE AND SHOULD AT LEAST BE SCEC LEVELS FOR TONIGHT...BUT COULD BE LOW END SCA OVER THE OFFSHORE WATERS. WINDS WILL SUBSIDE AND TURN MORE TO THE NORTHEAST FOR WEDNESDAY. FIRE WEATHER (TODAY)...WITH GUSTY NORTH WINDS AND VERY DRY AIR MOVING INTO THE AREA FOR THIS AFTERNOON...ELEVATED FIRE DANGER THREAT WILL EXIST OVER THE BRUSH COUNTRY AND INLAND COASTAL PLAINS. MINIMUM RH LEVELS COULD FALL TO AROUND 10 PERCENT THIS AFTERNOON. LONG TERM (WEDNESDAY NIGHT THROUGH TUESDAY)...MILD TEMPERATURES WILL CONTINUE THROUGH THE REST OF THE WORK WEEK AS AN UPPER LVL LOW CONTINUES TO BE CENTERED OVER THE NORTHERN CENTRAL STATES. SURFACE TO LOW LVLS OF THE ATMOSPHERE REMAINS RATHER DRY...THOUGH PACIFIC MOISTURE PLUME BEGINS WORKING INTO THE UPPER LVLS DURING THE END OF THE WEEK. THIS WILL LEAD INCREASED CLOUD COVER ACROSS MUCH OF THE REGION MIDWEEK. BY FRIDAY UPPER LVL LOW FINALLY OPENS AND TROUGH SWINGS THROUGH TO THE EAST. RIDGING WILL THEN OCCUR OVER THE WEEKEND...AND TEMPERATURES WILL WARM BACK UP AS ONSHORE FLOW RETURNS AND MOISTURE INCREASES IN THE LOWER LEVELS. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 94 57 83 56 78 / 10 10 10 10 10 VICTORIA 89 52 80 50 78 / 10 10 10 10 10 LAREDO 97 60 87 58 81 / 10 10 10 10 10 ALICE 94 55 84 53 79 / 10 10 10 10 10 ROCKPORT 88 59 80 59 76 / 10 10 10 10 10 COTULLA 93 52 85 52 79 / 10 10 10 10 10 KINGSVILLE 95 55 84 55 77 / 10 10 10 10 10 NAVY CORPUS 86 62 79 63 76 / 10 10 10 10 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS... BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR... COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM... COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. && $$ TMT/89...AVIATION
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
644 AM CDT TUE APR 29 2014 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 346 AM CDT TUE APR 29 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW UPPER LOW AND ASSOCIATED SURFACE SYSTEM OVER FAR SOUTHWEST IA. THIS SYSTEM IS EXPECTED TO MOVE SLOWLY NORTHEAST INTO WI THROUGH THIS PERIOD. EXPECT PERIODS OF RAIN TO MOVE NORTH THROUGH THE STATE THROUGH WED AS ENERGY ROTATES AROUND LOW. HEAVIER AREA OF RAIN NOW MOVING MOVING THROUGH SOUTHERN HALF OF STATE. DRY AIR VERY PRESENT ON APX EVENING SOUNDING BEING ADVECTED IN OVER NORTHERN WI ON STRONG EAST WINDS...LIMITING PCPN AMOUNTS SO FAR. THIS DRY AIR VERY EVIDENT OVER FAR NORTH WHERE DEW POINTS STILL IN THE 20S. AS PCPN MOVES IN OVER NORTH SEEING SNOW/SLEET SHOWING UP...THOUGH SURFACE TEMPS STILL MILD SO AM NOT LOOKING AT ANY ACCUMULATION. WILL CONTINUE TO CARRY MIX INTO THE MORNING HOURS. LOW LEVEL TEMP FIELDS POINT TO MAINLY RAIN THROUGH REMAINDER OF THE PERIOD AS WEAK WAA BRINGS 850 TEMP UP TO +2 OVER VILAS COUNTY BY TONIGHT. AS LOW MOVES NORTH LOOK FOR WINDS TO BACK OFF...BECOMING LIGHT LATER TONIGHT INTO WED. MAY SEE SOME FOG WITH LINGERING MOISTURE. WILL ADD TO MARINE ZONES AT THIS TIME AND LET LATER SHIFT DEBATE LAND ZONES. BEST MOISTURE/PW`S OVER 1 INCH NOW OFF TO THE EAST OF STATE...WILL DROP ISSUING ESF WITH LESSER QPF EXPECTED. TEMPS TO REMAIN BELOW SEASONABLE NORMS. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 346 AM CDT TUE APR 29 2014 UNSETTLED CONDITIONS WILL CONTINUE INTO THE WEEKEND AND POSSIBLY EARLY NEXT WEEK. FIRST...UPPER LOW WILL SLOWLY MOVE AWAY FROM THE AREA ON THURSDAY...THEN SEVERAL SYSTEMS MOVING THROUGH THE MEAN FLOW WILL BRING CHANCES FOR SHOWERS AT TIMES FRIDAY INTO EARLY NEXT WEEK. UPPER LOW EXPECTED TO SLOWLY MOVE ACROSS THE AREA WEDNESDAY NIGHT. WILL NEED TO WATCH FOR A POTENTIAL SHARS (SUBTLE HEAVY RAINFALL SIGNATURE EVENT) WITH THESE TYPES OF SYSTEMS DEPENDING ON LOCATION OF SHORTWAVE ENERGY AND LOW LEVEL CONVERGENCE AREAS. THESE TYPES OF SYSTEM COULD BRING CONSIDERABLY MORE RAIN THAT WHAT IS IN THE QPF FORECAST GRID. UNFORTUNATELY...WAY TOO EARLY TO DETERMINE IF OR WHERE THIS TYPE OF EVENT WOULD FORM. EVEN IF A SHARS EVENT DOES DEVELOP...IT WOULD BRING LOCALIZED HEAVIER RAINFALL TOTALS THAN WHAT IS IN THE CURRENT FORECAST AND COULD IMPACT RIVER FORECASTS. COOL CYCLONIC FLOW WILL CONTINUE TO BRING INSTABILITY SHOWERS ON THURSDAY WHICH MAY LINGER INTO THURSDAY EVENING...WITH POSSIBILITY OF AN ISOLATED SHOWER BETWEEN 06Z-12Z FRIDAY. ON FRIDAY...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED COLD FRONT WILL MOVE ACROSS THE REGION ON FRIDAY (MAYBE FRIDAY EVENING ACROSS THE EAST). COOL CYCLONIC FLOW...FORCING ALOFT AND FRONTAL BOUNDARY WITH DEW POINTS POOLING INTO THE LOWER TO MIDDLE 40S WILL BE SUFFICIENT FOR A CHANCE OF SHOWERS. LOOKED AT THUNDER PROSPECTS...DID NOT SUPPORT ADDING THUNDER AT THIS POINT. A STRONGER SHORTWAVE IS EXPECTED MOVE ACROSS THE WESTERN GREAT LAKES ON SATURDAY...BRINGING ANOTHER CHANCE OF SHOWERS. A WEAK BOUNDARY IS EXPECTED TO DROP ACROSS THE AREA DURING THE PEAK HEATING OF THE DAY ON SUNDAY...WARRANTING A CHANCE OF SHOWERS. A FEW SHOWERS MAY LINGER INTO SUNDAY EVENING...THEN DRY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF SUNDAY NIGHT INTO MONDAY MORNING. WITH THE EXPECTED CLOUDS AND SOME RAIN DURING THE DAY TIME HOURS...EXPECTED TEMPERATURES TO RUN BELOW NORMAL FOR MUCH OF THE PERIOD. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 640 AM CDT TUE APR 29 2014 AN UPPER LOW PRESSURE SYSTEM ACROSS MID SECTION OF THE COUNTRY WILL CONTINUE TO LIFT BANDS OF SHOWERS NORTH OVER THE STATE FOR MUCH OF THE WEEK AS IT MOVES NORTHEAST INTO THE STATE. CIGS WILL VARY FROM IVFR TO MVFR...LOWERING TO IFR AS THE LOW MOVES CLOSER TO THE STATE TONIGHT. WINDS ALSO EXPECTED TO BACK OFF AS THE LOW APPROACHES. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......RE AVIATION.......TE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
657 PM EDT Tue Apr 29 2014 ...STRONG TO SEVERE THUNDERSTORMS EXPECTED THROUGH WEDNESDAY... ...HEAVY RAINFALL WITH AREAS OF FLASH AND RIVERINE FLOODING EXPECTED AS WELL... .Near Term [Through Tonight]... During the late afternoon our CWA experienced a lull with mostly stratiform precipitation over land areas and scattered thunderstorms well offshore. However by 6 PM EDT...radar... satellite and upstream obs indicated next round of strong to possible severe convection entering our Wrn most counties in the form of a potent MCS tracking EWD across Wrn FL Panhandle. All this assocd with increasing moisture flux and high cape advecting newd ahead of mid-south cold front. Satellite water vapor shows increasingly tall Tcu advecting newd under strong moisture flux into srn edge of MCS aiding in cell mergers and convergence. This reflected in increasingly impressive lighting plots. Latest HRRR implies that Panhandle storms could become quite organized later this eve. A Severe tstm warning was just issued for these storms moving Ewd around 25 mph just before entering Walton County. SPENES estimates 1-2 inch per hour rainfall rates with this system. With redevelopment expected to occur on back edge of slow moving MCS and higher moisture flux/cape advancing Ewd...additional heavy rains are expected through this evening across especially FL Panhandle and adjacent SE AL/SW GA and will be closely monitored for flooding concerns in addition to severe weather. Weak steering flow and SWLY steering flow would favor training of incoming cells so isold areas could expect 3-5 inches which on top of already saturated grounds would aggravate flooding concerns. For now flash flood watch will remain in place through Wednesday evening for all but the Valdosta region and the SE Big Bend. && .Marine... Strong and gusty onshore winds over the Panhandle waters necessitated the issuance of a Small Craft Advisory thru sunrise as the pressure gradient tightens around an approaching cold front moving from west to east. Exercise caution level winds are expected for the remaining waters. After the cold front passes on Wednesday, offshore winds will prevail through the weekend until high pressure builds in the Gulf on Sunday switching our prevailing winds out of the east. && .Prev Discussion [319 PM EDT]... .Short Term [Wednesday Through Thursday Night]... The closed mid-upper level low over the Upper Mississippi River Valley will finally eject to the northeast and across the Great Lakes region on Thursday. Even so, the local area will remain under deep southwest flow. The associated surface cold front will move into our western zones Wednesday and slowly push east our FA by Thursday night. An ongoing severe weather threat will mark the beginning of the period as a squall continues to advance from west to east. The current thinking as that the leading edge of strong to severe convection will be entering our western GA zones and the western Florida Big Bend. Forecast CAPE values are over 2000 J/JG and local CAM models continue to generate very high updraft helicity and updraft velocity values, so an isolated strong tornado or two cannot be ruled out. There will be an accompanying flash flooding threat which is detailed below in the hydrology section. Rain chances will continue until the frontal passage late Thursday or Thursday night but the severe threat should end after Wednesday. .Long Term [Friday Through Tuesday]... The stubborn surface low that has been stuck over the CONUS for the past few days finally begins to lift into eastern Canada by Friday. The associated trailing cold front will finally push through our area for good bringing with it the chance for showers on Friday afternoon. Behind the front ridging will settle in place. Rain chances will be minimal and southerly flow at the end of the period will bring sticky conditions with high temperatures in the upper 80s and dewpoints near 60. .Aviation... [Through 18Z Wednesday] Rain and thunderstorms will come to an end this evening from west to east. Expect IFR/LIFR CIGS and VI`S to develop due to plentiful boundary layer moisture and frontal forcing. Winds will increase again tomorrow morning out of the south and additional thunderstorms will impact DHN and ABY, bringing potentially gusty winds and low CIGS/VI`S. .Fire Weather... No fire weather concerns. .Hydrology... Rainfall totals this morning are already in the 1 to 3 inch range across the region. Rain will continue this afternoon throughout most of the region. Another 1 to 3 inches is expected this afternoon, particularly in the eastern half of the CWA. Another round of rain and thunderstorms are expected tonight into tomorrow. This will bring an additional 2 to 5 inches of rainfall with isolated higher amounts possible. Flash flooding will be possible tomorrow. Flooding continues on the Suwannee River in the eastern Big Bend, but most other rivers have receded. Rainfall totals will be sufficient to bring many rivers into minor flood stage once again. There is uncertainty about how much the rivers will rise, since most of the rain hasn`t fallen yet. The most up-to-date river forecast information can always be found on our AHAPS page (below). http:/water.weather.gov/ahps2/index.php?wfo=tae. && .Preliminary Point Temps/PoPs... Tallahassee 70 84 67 80 59 / 40 60 50 50 50 Panama City 72 79 63 76 58 / 70 70 40 50 50 Dothan 70 78 59 76 53 / 80 70 40 40 30 Albany 70 81 63 77 55 / 60 70 60 40 30 Valdosta 69 87 67 80 57 / 30 50 50 50 50 Cross City 70 86 69 82 62 / 20 40 30 50 60 Apalachicola 73 79 66 75 58 / 40 60 40 50 60 && .TAE Watches/Warnings/Advisories... FL...Flash Flood Watch through Wednesday evening for Calhoun-Central Walton-Coastal Bay-Coastal Franklin-Coastal Gulf-Coastal Wakulla-Gadsden-Holmes-Inland Bay-Inland Franklin-Inland Gulf-Inland Wakulla-Inland Walton-Jackson-Leon-Liberty- South Walton-Washington. High Rip Current Risk through Wednesday evening for Coastal Bay- Coastal Franklin-Coastal Gulf-South Walton. GA...Flash Flood Watch through Wednesday evening for Baker-Ben Hill- Calhoun-Clay-Colquitt-Decatur-Dougherty-Early-Grady-Irwin- Lee-Miller-Mitchell-Quitman-Randolph-Seminole-Terrell- Thomas-Tift-Turner-Worth. AL...Flash Flood Watch through Wednesday evening for Coffee-Dale- Geneva-Henry-Houston. GM...Small Craft Advisory until 8 AM EDT Wednesday for Coastal waters from Apalachicola to Destin FL out 20 NM-Waters from Apalachicola to Destin FL from 20 to 60 NM. && $$ NEAR TERM...BLOCK SHORT TERM...BARRY LONG TERM...BARRY/WALSH AVIATION...BARRY/WALSH MARINE...BLOCK FIRE WEATHER...BLOCK HYDROLOGY...MCDERMOTT
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
412 PM EDT TUE APR 29 2014 .SYNOPSIS... A SLOW MOVING FRONTAL SYSTEM WILL APPROACH FROM THE WEST THROUGH WEDNESDAY. THE FRONT WILL EXTEND THROUGH THE FORECAST AREA WEDNESDAY NIGHT AND MOVE EAST OF THE AREA THURSDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... THE MIDDLE AFTERNOON ANALYSIS SHOWED A WEDGE FRONT NEAR THE NORTH CAROLINA AND SOUTH CAROLINA BORDER. SOUTH OF THIS FEATURE LI/S WERE -4 TO -7. RADAR AT 19Z NOT SHOWING ANY SHOWERS IN THE AREA. LAPS SOUNDINGS SUGGESTING MID LEVEL CAP AND TRIGGER FOR CONVECTION LACKING. THE THUNDERSTORM COMPLEX EXTENDING ALONG THE GULF COAST WAS LIMITING THE TRANSPORT OF MOISTURE NORTHWARD AND INTO THE FORECAST AREA. THE HRRR SHOWED LITTLE SHOWER COVERAGE DURING THE REST OF THE AFTERNOON AND OVERNIGHT. THIS IS SUPPORTED BY LATEST RAP MODEL. THE NAM INDICATES SURFACE-BASED LI/S -4 TO -6 TONIGHT WITH CONTINUED HIGH SHEAR. EXPECT H85 WINDS NEAR 35 KNOTS. THE SHEAR MAY BE ENHANCED IN THE NORTH PART IF THE WEDGE FRONT PERSISTS. SEVERE THUNDERSTORMS WILL BE POSSIBLE BECAUSE OF THE INSTABILITY AND SHEAR. HOWEVER...THE LIMITING FACTOR MAY CONTINUE TO BE A LACK OF DEEP MOISTURE IN THE WAKE OF THE LARGE THUNDERSTORM COMPLEX SOUTH OF THE FORECAST AREA AND LACK OF SHORT WAVE TRIGGER. BASED ON LATEST GUIDANCE WILL LOWER POPS OVERNIGHT...WITH CHANCE MAINLY ALONG THE NORTH CAROLINA BORDER NEAR STATIONARY FRONT. WITH COLD FRONT MOVING INTO NORTH GEORGIA LATE TONIGHT MAY SEE SHOWERS DEVELOPING IN THE WEST MIDLANDS/PIEDMONT...SO CHANCE POPS AND INCREASING TO THE EAST TOWARD MORNING. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF CLOUDINESS AND MIXING. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... MOISTURE SHOULD BECOME DEEP JUST AHEAD OF THE SLOW MOVING COLD FRONT. BELIEVE THE FRONT WILL BE JUST WEST OF THE FORECAST AREA WEDNESDAY AND EXTEND THROUGH THE AREA WEDNESDAY NIGHT. THE NAM SHOWS PRECIPITABLE WATER INCREASING TO NEAR 1.9 OF AN INCH BY WEDNESDAY AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE A 40-KNOT H85 JET. THE MOISTURE AND CONVERGENCE ASSOCIATED WITH THE FRONT SUPPORT LIKELY OR CATEGORICAL POPS. THE NAM INDICATES SURFACE-BASED LI/S NEAR -5 WEDNESDAY AND WEDNESDAY EVENING. THE INSTABILITY AND SHEAR SUPPORT POSSIBLE SEVERE THUNDERSTORMS. HIGH PRECIPITABLE WATER AND POSSIBLE TRAINING SUPPORTS HEAVY RAIN. THE NAM...GFS...AND SREF MEAN ARE ALL BELOW FLASH FLOOD GUIDANCE SO WE HAVE HELD OFF ISSUING A FLOOD WATCH FOR NOW. && .LONG TERM /THURSDAY THROUGH TUESDAY/... THE NAM AND GFS CONTINUE TO INDICATE DEEP MOISTURE WILL SHIFT EAST OF THE FORECAST AREA EARLY THURSDAY. THE FRONT WILL SHIFT JUST OFF THE COAST. THE NAM INDICATES SURFACE-BASED LI/S ABOVE 0 BY 12Z THURSDAY. THE SHOWER CHANCE SHOULD DIMINISH FROM WEST TO EAST. THE GFS AND ECMWF INDICATE A DRY PATTERN DURING THE REST OF THE MEDIUM-RANGE PERIOD. MOISTURE ASSOCIATED WITH THE FRONT APPEARS TO REMAIN SOUTH AND EAST OF THE AREA EARLY. DRY SURFACE RIDGING JUST TO THE SOUTH APPEARS TO DOMINATE DURING THE MIDDLE AND LATE PART OF THE PERIOD. THE GFS...ECMWF...AND EKD MOS PLUS GFS ENSEMBLE MEAN INDICATE POPS AROUND 20 PERCENT EARLY...AND LESS THAN 20 PERCENT DURING THE REST OF THE PERIOD. THE GUIDANCE WAS CONSISTENT WITH TEMPERATURES NEAR CLIMATOLOGY. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS INTO THE EVENING HOURS WITH CONDITIONS DETERIORATING OVERNIGHT. CLOUDINESS CONTINUES TO BLANKET THE REGION WHICH WILL ACT TO LIMIT CONVECTION AT THE TAF SITES THIS EVENING. THE BETTER CHANCE FOR STORMS LOOKS TO BE FURTHER NORTH OF THE TAF SITES CLOSER TO THE FRONTAL BOUNDARY EXTENDING THROUGH NORTH CAROLINA. AS THE COLD FRONT APPROACHES THE REGION FROM THE WEST OVERNIGHT EXPECT SHOWERS TO MOVE IN WITH CLOUD BASES LOWERING TO MVFR...POSSIBLY IFR...DURING THE EARLY MORNING HOURS. WENT WITH VCSH FOR NOW DUE TO LOW CONFIDENCE IN TIMING. WINDS WILL BE SOUTHERLY THROUGH THE PERIOD AROUND 11 KNOTS WITH GUSTS UP TO 18 KNOTS. .EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS THROUGH THURSDAY NIGHT AS THE FRONTAL SYSTEM SLOWLY CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
352 PM EDT TUE APR 29 2014 .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... MAIN CONCERN WILL BE WITH SEVERE POTENTIAL THIS EVENING INTO THE OVERNIGHT WITH THE ANTICIPATED NEXT WAVE OF CONVECTION. THE DAYTIME PERIOD HAS BEEN LARGELY A LULL IN ACTIVITY DUE TO UPSTREAM CONVECTION ALONG NORTHERN FLORIDA AND CAPPING FROM LINGERING MIDLEVEL CLOUD COVERAGE THAT HAS FINALLY STARTED TO MIX OUT. OUT OF THE SUITE OF HI-RES SOLUTIONS...THE RUC...LOCAL WRF...AND HRRR HAVE BEEN TRENDING THE BEST WITH PREVIOUS DEVELOPMENT AND LACK THEREOF SO HAVE LEANED HEAVILY TOWARD THEM WITH OVERNIGHT POPS AND GREATEST STORM POTENTIAL. THESE MODELS AGREE WITH CONVECTIVE INITIATION OCCURRING NEAR THE MS/AL BORDER BY 20-21Z...WHICH SEEMS LEGIT GIVEN AN OBSERVED MESO-LOW TRACKING ALONG THE SFC FRONT IN SOUTHERN MS AND ALREADY SEEING SOME ENHANCED CU FIELD DEVELOPING. THE EVOLUTION OF DEVELOPMENT BRINGS CELLS INTO WESTERN PORTIONS OF THE CWA AFTER 00Z TONIGHT THEN SPREADING NORTH OF THE I-85 CORRIDOR. THE INSTABILITY AND SHEAR PARAMETERS ARE STILL QUITE FAVORABLE FOR STRONG TO SEVERE DEVELOPMENT THIS EVENING AND EARLY MORNING WITH DAMAGING WINDS AND TORNADOES AS THE MAIN THREATS. MLCAPE VALUES ARE LOOKING TO BE NEAR 1000 J/KG...0-1KM HELICITY AROUND 150 M2/S2...0-1KM BULK SHEAR NEAR 30 KTS...AND 0-6KM BULK IN THE 50-60 KT ZONE FOR THE NORTHWEST HALF OF THE AREA. THE BEST CHANCE FOR SEVERE DEVELOPMENT LOOKS TO BE IN THE 01Z-07Z PERIOD ALONG AND NORTH OF THE I-85 CORRIDOR INCLUDING THE ATLANTA METRO AREA. THIS ALSO COINCIDES WITH INCREASING SREF ENSEMBLE MEAN STP VALUES APPROACHING 2. SHEAR VECTOR ORIENTATION SUPPORTS EMBEDDED OR SEMI-DISCRETE SUPERCELL CONVECTIVE MODE IN THE 00Z-09Z PERIOD...THEN BECOMES MORE PARALLEL AS A MORE LINEAR SWATH SETS UP. THIS AGREES WITH CONSENSUS AMONG THE MODELS AS TRAINING CELLS STALLING ALONG THE I-85 CORRIDOR IN THE MORNING HOURS IS POSSIBLE. THERE COULD THEREFORE BE AN INCREASED FLASH FLOODING THREAT. SEE HYDRO SECTION BELOW FOR MORE DETAILS ON QPF WITH THE EVENT. THE FRONT FINALLY PUSHES THROUGH WEDNESDAY THOUGH THE ENVIRONMENT LOOKS LESS FAVORABLE THAN OVERNIGHT TONIGHT FOR SEVERE POTENTIAL. WHILE THE GREATEST POPS WILL TRANSITION TO SOUTHEAST CWA FOR WEDNESDAY AFTERNOON...CANNOT RULE OUT SOME STRONG TO ISOLATED SEVERE POTENTIAL ATTM. BAKER .LONG TERM /THURSDAY THROUGH TUESDAY/... NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. THE COLD FRONT BRINGING SEVERE WEATHER TO THE STATE IN THE SHORT TERM IS EXPECTED TO EXIT THE AREA LATE WEDNESDAY NIGHT..ENDING THE THREAT OF SEVERE STORMS. THE DIFFICULTY THEN BECOMES THE SW UPPER FLOW CONTINUES THROUGH ABOUT 12Z SAT WITH POTENTIAL FOR MAINLY LIGHT SHOWER AND THUNDERSTORM CHANCES OVER MAINLY SE PORTION OF THE CWA AS SOME LESSER MOISTURE MOVES THROUGH THE FLOW. AFTER 12Z SAT THE UPPER TROUGH MOVES ACROSS THE AREA WITH A DRY FORECAST FOR THE REST OF THE LONG TERM. TEMPERATURES WILL TRANSITION TO BELOW NORMAL AT THE START OF THE LONG TERM THEN BACK TO NORMAL ON SATURDAY AND THEN ABOVE NORMAL THE REST OF THE LONG TERM. 01 && .HYDROLOGY... HPC QPF LOOKS REASONABLE GIVEN THE AFOREMENTIONED STORM TRENDS IN THE HI-RES SOLUTIONS. THE HEAVIEST AMOUNTS LOOK TO FALL IN THE OVERNIGHT PERIOD TONIGHT WITH A WIDESPREAD 2 INCHES AND POSSIBLY HIGHER AMOUNTS WITH TRAINING CELLS ALONG AND NEAR THE I-85 CORRIDOR. WILL KEEP THE CURRENT FLOOD WATCH GOING THROUGH WEDNESDAY NIGHT. BAKER && .AVIATION... 18Z UPDATE... INITIAL VFR CONDITIONS LOWERING TO MVFR OVERNIGHT WITH INCREASED PRECIP CHANCE FROM WEST. EXPECT CU FIELD TO DEVELOP NEAR 4 KFT THIS AFTERNOON AND TSRA POTENTIAL MAINLY FOR NORTHERN SITES ON THE INCREASE THIS EVENING IN THE 01Z-05Z PERIOD AND COULD SEE SOME STRONG TO SEVERE STORMS. MAIN THREATS WITH STRONGER DEVELOPMENT WILL BE DAMAGING WINDS AND TORNADOES. PRECIP AXIS MAY LINGER ACROSS KATL AND NEARBY SITES THROUGH THE EARLY MORNING WITH SOME HEAVY RAIN POSSIBLE AS WELL. DEVELOPMENT MAY STRUGGLE TO GET AS FAR SOUTHEAST AS KMCN TONIGHT. WINDS STAYING MAINLY SW 12-15 KTS GUSTING 18-22 KTS. //ATL CONFIDENCE...18Z UPDATE... MEDIUM ON OVERNIGHT PRECIP. HIGH ON ALL ELSE. BAKER && .PRELIMINARY POINT TEMPS/POPS... ATHENS 65 78 55 74 / 100 80 50 20 ATLANTA 65 75 53 71 / 100 60 20 10 BLAIRSVILLE 61 70 50 67 / 100 70 20 10 CARTERSVILLE 66 76 49 71 / 100 60 10 10 COLUMBUS 68 80 57 74 / 60 60 40 20 GAINESVILLE 64 75 53 70 / 100 70 30 10 MACON 68 82 58 75 / 40 70 60 30 ROME 65 76 48 70 / 90 60 10 10 PEACHTREE CITY 65 76 51 72 / 100 60 20 20 VIDALIA 70 86 67 78 / 30 60 60 50 && .FFC WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR THE FOLLOWING ZONES: BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY... BUTTS...CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA... CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...CRISP... DADE...DAWSON...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL... FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...GLASCOCK... GORDON...GREENE...GWINNETT...HALL...HANCOCK...HARALSON... HARRIS...HEARD...HENRY...HOUSTON...JACKSON...JASPER... JEFFERSON...JOHNSON...JONES...LAMAR...LAURENS...LUMPKIN... MACON...MADISON...MARION...MERIWETHER...MONROE...MONTGOMERY... MORGAN...MURRAY...MUSCOGEE...NEWTON...NORTH FULTON...OCONEE... OGLETHORPE...PAULDING...PEACH...PICKENS...PIKE...POLK... PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING... STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR... TOOMBS...TOWNS...TREUTLEN...TROUP...TWIGGS...UNION...UPSON... WALKER...WALTON...WARREN...WASHINGTON...WEBSTER...WHEELER... WHITE...WHITFIELD...WILCOX...WILKES...WILKINSON. && $$ SHORT TERM...BAKER LONG TERM....01 AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
344 PM EDT TUE APR 29 2014 .SYNOPSIS... A SLOW MOVING FRONTAL SYSTEM WILL APPROACH FROM THE WEST THROUGH WEDNESDAY. THE FRONT WILL EXTEND THROUGH THE FORECAST AREA WEDNESDAY NIGHT AND MOVE EAST OF THE AREA THURSDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... THE MIDDLE AFTERNOON ANALYSIS SHOWED A WEDGE FRONT NEAR THE NORTH CAROLINA AND SOUTH CAROLINA BORDER. SOUTH OF THIS FEATURE LI/S WERE -4 TO -7. RADAR AT 19Z NOT SHOWING ANY SHOWERS IN THE AREA. LAPS SOUNDINGS SUGGESTING MID LEVEL CAP AND TRIGGER FOR CONVECTION LACKING. THE THUNDERSTORM COMPLEX EXTENDING ALONG THE GULF COAST WAS LIMITING THE TRANSPORT OF MOISTURE NORTHWARD AND INTO THE FORECAST AREA. THE HRRR SHOWED LITTLE SHOWER COVERAGE DURING THE REST OF THE AFTERNOON AND OVERNIGHT. THIS IS SUPPORTED BY LATEST RAP MODEL. THE NAM INDICATES SURFACE-BASED LI/S -4 TO -6 TONIGHT WITH CONTINUED HIGH SHEAR. EXPECT H85 WINDS NEAR 35 KNOTS. THE SHEAR MAY BE ENHANCED IN THE NORTH PART IF THE WEDGE FRONT PERSISTS. SEVERE THUNDERSTORMS WILL BE POSSIBLE BECAUSE OF THE INSTABILITY AND SHEAR. HOWEVER...THE LIMITING FACTOR MAY CONTINUE TO BE A LACK OF DEEP MOISTURE IN THE WAKE OF THE LARGE THUNDERSTORM COMPLEX SOUTH OF THE FORECAST AREA AND LACK OF SHORT WAVE TRIGGER. BASED ON LATEST GUIDANCE WILL LOWER POPS OVERNIGHT...WITH CHANCE MAINLY ALONG THE NORTH CAROLINA BORDER NEAR STATIONARY FRONT. WITH COLD FRONT MOVING INTO NORTH GEORGIA LATE TONIGHT MAY SEE SHOWERS DEVELOPING IN THE WEST MIDLANDS/PIEDMONT...SO CHANCE POPS AND INCREASING TO THE EAST TOWARD MORNING. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF CLOUDINESS AND MIXING. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... MOISTURE SHOULD BECOME DEEP JUST AHEAD OF THE SLOW MOVING COLD FRONT. BELIEVE THE FRONT WILL BE JUST WEST OF THE FORECAST AREA WEDNESDAY AND EXTEND THROUGH THE AREA WEDNESDAY NIGHT. THE NAM SHOWS PRECIPITABLE WATER INCREASING TO NEAR 1.9 OF AN INCH BY WEDNESDAY AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE A 40-KNOT H85 JET. THE MOISTURE AND CONVERGENCE ASSOCIATED WITH THE FRONT SUPPORT LIKELY OR CATEGORICAL POPS. THE NAM INDICATES SURFACE-BASED LI/S NEAR -5 WEDNESDAY AND WEDNESDAY EVENING. THE INSTABILITY AND SHEAR SUPPORT POSSIBLE SEVERE THUNDERSTORMS. HIGH PRECIPITABLE WATER AND POSSIBLE TRAINING SUPPORTS HEAVY RAIN. THE NAM...GFS...AND SREF MEAN ARE ALL BELOW FLASH FLOOD GUIDANCE SO WE HAVE HELD OFF ISSUING A FLOOD WATCH FOR NOW. && .LONG TERM /THURSDAY THROUGH TUESDAY/... THE NAM AND GFS CONTINUE TO INDICATE DEEP MOISTURE WILL SHIFT EAST OF THE FORECAST AREA EARLY THURSDAY. THE FRONT WILL SHIFT JUST OFF THE COAST. THE NAM INDICATES SURFACE-BASED LI/S ABOVE 0 BY 12Z THURSDAY. THE SHOWER CHANCE SHOULD DIMINISH FROM WEST TO EAST. THE GFS AND ECMWF INDICATE A DRY PATTERN DURING THE REST OF THE MEDIUM-RANGE PERIOD. MOISTURE ASSOCIATED WITH THE FRONT APPEARS TO REMAIN SOUTH AND EAST OF THE AREA EARLY. DRY SURFACE RIDGING JUST TO THE SOUTH APPEARS TO DOMINATE DURING THE MIDDLE AND LATE PART OF THE PERIOD. THE GFS...ECMWF...AND EKD MOS PLUS GFS ENSEMBLE MEAN INDICATE POPS AROUND 20 PERCENT EARLY...AND LESS THAN 20 PERCENT DURING THE REST OF THE PERIOD. THE GUIDANCE WAS CONSISTENT WITH TEMPERATURES NEAR CLIMATOLOGY. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS INTO THE EVENING HOURS WITH CONDITIONS DETERIORATING LATE THIS EVENING AND OVERNIGHT. CLOUDINESS CONTINUES TO BLANKET THE REGION LIMITING CONVECTION. SATELLITE IMAGERY SHOWS SOME BREAKS DEVELOPING IN THE UPPER CLOUDS ACROSS THE AREA WHICH SHOULD ALLOW FOR A BIT MORE HEATING AND ALLOW SHOWERS AND THUNDERSTORMS TO DEVELOP OVER THE NEXT COUPLE OF HOURS. WITH THE CLOUDS SUPPRESSING CONVECTION CONFIDENCE REMAINS LOW IN TIMING AND COVERAGE OF SHOWERS AND THUNDERSTORMS SO HAVE REMAINED WITH VCTS FROM LATE AFTERNOON THROUGH THE EVENING HOURS AND WILL ADJUST AS NEEDED. AS THE FRONT MOVES CLOSER TO THE REGION OVERNIGHT EXPECT SHOWERS TO BECOME MORE WIDESPREAD WITH CLOUD BASES CONTINUING TO LOWER MVFR...POSSIBLE IFR...DURING THE EARLY MORNING HOURS. WINDS WILL BE SOUTHERLY THROUGH THE PERIOD AROUND 11 KNOTS WITH GUSTS UP TO 18 KNOTS. .EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS THROUGH THURSDAY NIGHT AS THE FRONTAL SYSTEM SLOWLY CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
232 PM EDT TUE APR 29 2014 .SYNOPSIS... A SLOW MOVING FRONTAL SYSTEM WILL APPROACH FROM THE WEST THROUGH WEDNESDAY. THE FRONT WILL EXTEND THROUGH THE FORECAST AREA WEDNESDAY NIGHT AND MOVE EAST OF THE AREA THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... THE MIDDLE AFTERNOON ANALYSIS SHOWED A WEDGE FRONT NEAR THE NORTH CAROLINA AND SOUTH CAROLINA BORDER. SOUTH OF THIS FEATURE LI/S WERE -4 TO -7. SHOWERS WERE ISOLATED MAINLY BECAUSE OF A LACK OF DEEP MOISTURE AND LOW-LEVEL FORCING WITH THE COLD FRONT STILL WELL TO THE WEST. THE THUNDERSTORM COMPLEX EXTENDING ALONG THE GULF COAST WAS LIMITING THE TRANSPORT OF MOISTURE NORTHWARD AND INTO THE FORECAST AREA. THE HRRR SHOWED LITTLE SHOWER COVERAGE DURING THE REST OF THE AFTERNOON. THE NAM INDICATES SURFACE-BASED LI/S -4 TO -6 TONIGHT WITH CONTINUED HIGH SHEAR. EXPECT H85 WINDS NEAR 35 KNOTS. THE SHEAR MAY BE ENHANCED IN THE NORTH PART IF THE WEDGE FRONT PERSISTS. SEVERE THUNDERSTORMS WILL BE POSSIBLE BECAUSE OF THE INSTABILITY AND SHEAR. HOWEVER...THE LIMITING FACTOR MAY CONTINUE TO BE A LACK OF DEEP MOISTURE IN THE WAKE OF THE LARGE THUNDERSTORM COMPLEX SOUTH OF THE FORECAST AREA. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF CLOUDINESS AND MIXING. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... MOISTURE SHOULD BECOME DEEP JUST AHEAD OF THE SLOW MOVING COLD FRONT. BELIEVE THE FRONT WILL BE JUST WEST OF THE FORECAST AREA WEDNESDAY AND EXTEND THROUGH THE AREA WEDNESDAY NIGHT. THE NAM SHOWS PRECIPITABLE WATER INCREASING TO NEAR 1.9 OF AN INCH BY WEDNESDAY AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE A 40-KNOT H85 JET. THE MOISTURE AND CONVERGENCE ASSOCIATED WITH THE FRONT SUPPORT LIKELY OR CATEGORICAL POPS. THE NAM INDICATES SURFACE-BASED LI/S NEAR -5 WEDNESDAY AND WEDNESDAY EVENING. THE INSTABILITY AND SHEAR SUPPORT POSSIBLE SEVERE THUNDERSTORMS. HIGH PRECIPITABLE WATER AND POSSIBLE TRAINING SUPPORTS HEAVY RAIN. THE NAM...GFS...AND SREF MEAN ARE ALL BELOW FLASH FLOOD GUIDANCE SO WE HAVE HELD OFF ISSUING A FLOOD WATCH FOR NOW. && .LONG TERM /THURSDAY THROUGH TUESDAY/... THE NAM AND GFS CONTINUE TO INDICATE DEEP MOISTURE WILL SHIFT EAST OF THE FORECAST AREA EARLY THURSDAY. THE FRONT WILL SHIFT JUST OFF THE COAST. THE NAM INDICATES SURFACE-BASED LI/S ABOVE 0 BY 12Z THURSDAY. THE SHOWER CHANCE SHOULD DIMINISH FROM WEST TO EAST. THE GFS AND ECMWF INDICATE A DRY PATTERN DURING THE REST OF THE MEDIUM-RANGE PERIOD. MOISTURE ASSOCIATED WITH THE FRONT APPEARS TO REMAIN SOUTH AND EAST OF THE AREA EARLY. DRY SURFACE RIDGING JUST TO THE SOUTH APPEARS TO DOMINATE DURING THE MIDDLE AND LATE PART OF THE PERIOD. THE GFS...ECMWF...AND EKD MOS PLUS GFS ENSEMBLE MEAN INDICATE POPS AROUND 20 PERCENT EARLY...AND LESS THAN 20 PERCENT DURING THE REST OF THE PERIOD. THE GUIDANCE WAS CONSISTENT WITH TEMPERATURES NEAR CLIMATOLOGY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS INTO THE EVENING HOURS WITH CONDITIONS DETERIORATING LATE THIS EVENING AND OVERNIGHT. CLOUDINESS CONTINUES TO BLANKET THE REGION LIMITING CONVECTION. SATELLITE IMAGERY SHOWS SOME BREAKS DEVELOPING IN THE UPPER CLOUDS ACROSS THE AREA WHICH SHOULD ALLOW FOR A BIT MORE HEATING AND ALLOW SHOWERS AND THUNDERSTORMS TO DEVELOP OVER THE NEXT COUPLE OF HOURS. WITH THE CLOUDS SUPPRESSING CONVECTION CONFIDENCE REMAINS LOW IN TIMING AND COVERAGE OF SHOWERS AND THUNDERSTORMS SO HAVE REMAINED WITH VCTS FROM LATE AFTERNOON THROUGH THE EVENING HOURS AND WILL ADJUST AS NEEDED. AS THE FRONT MOVES CLOSER TO THE REGION OVERNIGHT EXPECT SHOWERS TO BECOME MORE WIDESPREAD WITH CLOUD BASES CONTINUING TO LOWER MVFR...POSSIBLE IFR...DURING THE EARLY MORNING HOURS. WINDS WILL BE SOUTHERLY THROUGH THE PERIOD AROUND 11 KNOTS WITH GUSTS UP TO 18 KNOTS. .EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS THROUGH THURSDAY NIGHT AS THE FRONTAL SYSTEM SLOWLY CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
231 PM EDT TUE APR 29 2014 .PREV DISCUSSION... /ISSUED 1122 AM EDT TUE APR 29 2014/ ..STRONG TO SEVERE STORMS LOOKING TO BUILD BACK INTO WESTERN PORTIONS OF AREA LATE AFTERNOON INTO EVENING... .UPDATE... MADE SIGNIFICANT UPDATES TO POP AND WEATHER TRENDS TODAY AS MAJORITY OF GUIDANCE AND OBS TRENDS SUGGEST LULL IN ACTIVITY UNTIL AFTER ABOUT 21Z THIS AFTERNOON. SOME UPSTREAM CONVECTION ALONG THE FLORIDA PANHANDLE MAY ALSO CONTRIBUTE TO THE BREAK IN ACTION. OF THE SUITE OF HI-RES SOLUTIONS...THE RUC HAS VERIFIED THE BEST INITIALLY AND TRIGGERS DEVELOPMENT ALONG THE MISSISSIPPI/ALABAMA BORDER WHICH SEEMS LEGIT GIVEN AN AREA OF SOLAR SHELTERING OCCURRING WITH LINGERING MORNING CLOUD COVERAGE. STORMS SHOULD MAKE THERE WAY INTO THE WESTERN PORTIONS OF THE CWA NEAR 23/00Z. STILL DAMAGING WIND AND TORNADO THREAT GIVEN INSTABILITY AND SHEAR PARAMETERS WORKING INTO NORTHWEST HALF OF CWA THOUGH UNCERTAINTY OF IT PROPAGATING INTO EAST CENTRAL GA. ALSO LATEST HPC QPF LOOKS REASONABLE SO HAVE UPDATED TOTALS TO GET AN ADDITIONAL 2-3 INCHES THROUGH WEDNESDAY. PREVIOUS DISCUSSION FOLLOWS... BAKER && PREV DISCUSSION... /ISSUED 745 AM EDT TUE APR 29 2014/ .SHORT TERM /TODAY THROUGH WEDNESDAY/... BROAD CLOSED UPPER LOW OVER THE MID WEST WILL PERSIST THROUGH THE PERIOD. THE CYCLONIC UPPER FLOW WILL SEND SEVERAL SHORT WAVES THROUGH THE SOUTHEAST STATES THROUGH WEDNESDAY WITH PERIODS OF SHOWERS AND THUNDERSTORMS. TIMING OF THESE WAVES IS DIFFICULT...AND THERE ARE ALSO UNCERTAINTIES CONCERNING THE EVOLUTION OF CURRENT CONVECTION. THERE MAY BE A BRIEF BREAK AFTER THIS MORNINGS ACTIVITY WITH REDEVELOPMENT EXPECTED THIS AFTERNOON AND EVENING. HAVE GENERALLY KEPT POPS HIGH ACROSS MUCH OF THE CWA. THE SURFACE FRONT MAY DRIFT INTO NORTHWEST GA ON WEDNESDAY. HAVE SHOWN SOME DECREASE IN POPS ACROSS THE NORTHWEST ON WEDNESDAY...BUT ONLY A FEW DEGREES OFF THE AFTERNOON MAX TEMPERATURES. 41 && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... COLD FRONT EXPECTED TO EXIT THE AREA LATE WEDNESDAY NIGHT..ENDING THUNDERSTORM CHANCES. THE DIFFICULTY THEN BECOMES THE SW UPPER FLOW CONTINUES THRU ABOUT 12Z SAT WITH POTENTIAL FOR MAINLY LIGHT SHOWER CHANCES OVER MAINLY CENTRAL GA AS SOME LESSER MOISTURE MOVES THROUGH THE FLOW. AFTER 12Z SAT THE UPPER TROUGH MOVES ACROSS THE AREA WITH A DRY FORECAST FOR THE REST OF THE LONG TERM. TEMPERATURES WILL TRANSITION TO BELOW NORMAL AT THE START OF THE LONG TERM THEN BACK TO NORMAL ON SATURDAY AND THEN ABOVE NORMAL THE REST OF THE LONG TERM. BDL && .HYDROLOGY... A FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY NIGHT HIGHLIGHTING THE IMPACTS OF 2 TO 4 INCHES IN NORTH GA TO 1 TO 2 INCHES CENTRAL GA. ISOLATED HIGHER AMOUNTS WILL BE POSSIBLE. THESE RAINFALL AMOUNTS SHOULD CAUSE WIDESPREAD MINOR AREAL AND RIVER FLOODING. THE GREATEST FLASH FLOOD THREAT WILL BE IN NORTH GA IN URBAN AREAS AND IN ROLLING HILLS OR MOUNTAINOUS TERRAINS WITH HIGH RAINFALL RATES. MOST STREAMFLOWS ARE RUNNING NEAR NORMAL NORTH GA TO WELL ABOVE NORMAL CENTRAL GA. && .AVIATION... 18Z UPDATE... INITIAL VFR CONDITIONS LOWERING TO MVFR OVERNIGHT WITH INCREASED PRECIP CHANCE FROM WEST. EXPECT CU FIELD TO DEVELOP NEAR 4 KFT THIS AFTERNOON AND TSRA POTENTIAL MAINLY FOR NORTHERN SITES ON THE INCREASE THIS EVENING IN THE 01Z-05Z PERIOD AND COULD SEE SOME STRONG TO SEVERE STORMS. MAIN THREATS WITH STRONGER DEVELOPMENT WILL BE DAMAGING WINDS AND TORNADOES. PRECIP AXIS MAY LINGER ACROSS KATL AND NEARBY SITES THROUGH THE EARLY MORNING WITH SOME HEAVY RAIN POSSIBLE AS WELL. DEVELOPMENT MAY STRUGGLE TO GET AS FAR SOUTHEAST AS KMCN TONIGHT. WINDS STAYING MAINLY SW 12-15 KTS GUSTING 18-22 KTS. //ATL CONFIDENCE...18Z UPDATE... MEDIUM ON OVERNIGHT PRECIP. HIGH ON ALL ELSE. BAKER && .PRELIMINARY POINT TEMPS/POPS... ATHENS 75 66 79 55 / 40 80 90 60 ATLANTA 75 66 75 54 / 50 80 90 20 BLAIRSVILLE 71 61 70 49 / 70 90 90 20 CARTERSVILLE 76 64 74 50 / 60 90 90 20 COLUMBUS 78 67 78 57 / 40 70 90 40 GAINESVILLE 74 65 73 53 / 40 90 90 20 MACON 77 69 81 58 / 80 60 80 60 ROME 79 64 74 50 / 70 90 80 20 PEACHTREE CITY 77 67 75 53 / 40 80 90 20 VIDALIA 82 69 83 63 / 50 50 60 70 && .FFC WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR THE FOLLOWING ZONES: BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY... BUTTS...CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA... CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...CRISP... DADE...DAWSON...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL... FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...GLASCOCK... GORDON...GREENE...GWINNETT...HALL...HANCOCK...HARALSON... HARRIS...HEARD...HENRY...HOUSTON...JACKSON...JASPER... JEFFERSON...JOHNSON...JONES...LAMAR...LAURENS...LUMPKIN... MACON...MADISON...MARION...MERIWETHER...MONROE...MONTGOMERY... MORGAN...MURRAY...MUSCOGEE...NEWTON...NORTH FULTON...OCONEE... OGLETHORPE...PAULDING...PEACH...PICKENS...PIKE...POLK... PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING... STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR... TOOMBS...TOWNS...TREUTLEN...TROUP...TWIGGS...UNION...UPSON... WALKER...WALTON...WARREN...WASHINGTON...WEBSTER...WHEELER... WHITE...WHITFIELD...WILCOX...WILKES...WILKINSON. && $$ SHORT TERM...41/BAKER LONG TERM....BDL AVIATION...BAKER
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 PM EDT TUE APR 29 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 340 PM EDT TUE APR 29 2014 18Z SFC ANALYSIS SHOWS OUR NEMESIS OF A BROAD STACKED LOW CENTERED OVER EASTERN IOWA. EAST KENTUCKY REMAINS IN THE SYSTEM/S SOUPY WARM SECTOR AS DEWPOINTS ARE STARTING TO COME BACK UP FROM THE MIDDAY DROPOFF WITH SOME NOW TO NEAR 60 DEGREES IN THE EAST. EXPECT THESE TO CONTINUE TO COME UP THROUGH THE REST OF THE AFTERNOON. TEMPERATURES...MEANWHILE...ARE GENERALLY IN THE MID AND UPPER 70S THROUGH THE AREA. THIS IS ENOUGH FOR SOME SHOWERS AND THUNDERSTORMS TO DEVELOP OVER THE EAST IN THE WAKE OF THIS MORNING/S BOUNDARY AND ITS ILL-FATED ATTEMPT TO PULL AWAYS FROM THIS PART OF THE STATE. THIS BONUS CONVECTION WILL NEED TO BE WATCHED FOR STRONGER DEVELOPMENT GIVEN THE ENVIRONMENT...BUT THE MAIN THREAT LIKELY ARRIVES FOR EAST KENTUCKY CLOSER TOWARD SUNSET AND FROM THE SOUTHWEST. WINDS ARE BREEZY OUT OF THE SOUTHWEST FOR MOST OF THE AREA WITH GUSTS TO 20 KTS OR SO. THE MODELS REMAIN IN PRETTY GOOD AGREEMENT ALOFT WITH THE BROAD CUT OFF LOW SLOWLY TUMBLING NORTHEAST INTO THE GREAT LAKES BY THURSDAY MORNING. THIS PROCESS WILL INVOLVE A COUPLE OF LINGERING SHORTWAVES RIDING THE FAST MID LEVEL FLOW BENEATH THE LOW...RUNNING ACROSS WESTERN KENTUCKY AND THEN NORTHEAST INTO THE OHIO VALLEY. THE FIRST OF THESE MOVES THROUGH KENTUCKY TOWARD MIDNIGHT WHILE ANOTHER PASSES BY LATER WEDNESDAY. HAVE FOLLOWED A MODEL BLEND FOR THE FORECAST WHILE LEANING TOWARD THE HRRR AND NAM12 FOR DETAILS TONIGHT. SENSIBLE WEATHER WILL FEATURE AN ACTIVE EVENING AND EARLY OVERNIGHT WITH A DECENT POTENTIAL FOR DAMAGING WIND GUSTS FROM THE STRONGER STORMS WHILE LARGE HAIL AND AN ISOLATED TORNADO CANNOT BE RULED OUT SHOULD BE SOME DISCREET CELLS EXHIBIT SUPERCELL CHARACTERISTICS. HAVE TIMED THESE THROUGH THE CWA MAINLY IN THE EVENING EXPECTING MORE STABLE AIR TO DEVELOP AFTER 06Z FROM THE EVENING STORMS. HOWEVER... LOCALIZED HEAVY RAIN WILL REMAIN A CONCERN WHERE ANY STORMS TRAIN. MORE WIDESPREAD RAINS OVER THE CUMBERLAND VALLEY WILL NEED TO BE WATCHED CLOSELY AS THE FFG IS THE LOWEST THERE OWING TO THE TWO PLUS INCHES THAT FELL THERE LAST NIGHT. THERE REMAINS JUST TOO MUCH UNCERTAINTY TO GO WITH A FLOOD WATCH FOR THIS PART OF THE EAST KENTUCKY WITH THE GFS KEEPING ITS HEAVIER BAND TO THE NORTHWEST AND THE NAM PLACING ITS OWN TO THE EAST OF THE LOWER FFG AREAS. WILL MONITOR THE SITUATION THROUGH THE EVENING FOR A POSSIBLE SHORTER FUSE WATCH DEPENDING HOW THE STORMS AND ANY TRAINING DEVELOPS. FOR WEDNESDAY...HAVE INCLUDED A SLIGHT CHANCE OF THUNDER THROUGH NOON IN THE WEST UNTIL THE LIS GO STRONGLY POSITIVE IN THE AFTERNOON AS THE SFC WINDS GO WEST AND A COLD FRONT MOVES ON THROUGH. DID DROP THE THUNDER FURTHER EAST WITH TIME. CARRIED A SMALL CHANCE OF SHOWERS THROUGH THE EVENING AND INTO THE NIGHT OVER THE EASTERN PARTS OF THE AREA...BUT RAINFALL AMOUNTS AND CONVECTIVE DEVELOPMENT WILL BE RATHER PALTRY POST COLD FRONT. USED THE CONSSHORT...AND THE BC VERSION...AS A STARTING POINT FOR THE GRIDS THROUGH THE NEXT 24 HOURS WITH THE CONSALL PRELOADED THEREAFTER. MADE ONLY SOME SMALL ADJUSTMENTS TO THE NUMBERS MAINLY TO CAPTURE THE CURRENT CONDITIONS AND TRENDS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL GUIDANCE TONIGHT AND THROUGH THE FORECAST...CLOSER TO THE MET NUMBERS. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 PM EDT TUE APR 29 2014 MODELS REMAIN IN GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER AIR PATTERN THROUGH THE END OF THE THE WEEK AND INTO EARLY NEXT WEEK. THE LARGE UPPER LOW OVER THE UPPER MS VALLEY/UPPER GREAT LAKES AT THE START OF THE PERIOD WILL MAKES ITS WAY INTO CANADA ON FRIDAY. AFTER THIS THERE WILL BE OCCASIONAL SHORT WAVE TROUGHS PASSING BY AS A MEAN LONG WAVE TROUGH REMAINS OVER THE EASTERN PART OF THE U.S. INTO EARLY NEXT WEEK. ANOTHER UPPER LOW IS FORECAST TO MOVE ACROSS THE NORTHERN GREAT LAKES LATE IN THE WEEKEND AND INTO NEW ENGLAND BY EARLY NEXT WEEK. THE PRIMARY FORECAST CHALLENGE REVOLVES AROUND PRECIPITATION CHANCES WITH ANY PASSING SHORT WAVES...AND THE PASSAGE OF A WEAK COLD FRONT THIS WEEKEND. HAVE FOLLOWED A BLENDED MODEL AND INHERITED FORECAST APPROACH FOR RAIN CHANCES FOR MOST OF THE LONG RANGE PERIOD WHICH YIELDS VERY LOW PROBABILITIES FOR MAINLY AFTERNOON SHOWERS EACH DAY FROM THURSDAY THROUGH SUNDAY. WILL NOT MENTION ANY RAIN CHANCE FOR MONDAY OR TUESDAY BUT LOW RAIN CHANCES MAY NEED TO BE INTRODUCED IN LATER FORECASTS AS IT APPEARS A WARM FRONT WILL BE MOVING ACROSS THE AREA. BELOW NORMAL TEMPERATURES WILL PREVAIL THROUGH THE FIRST PART OF THE FORECAST PERIOD...WITH RISING HEIGHTS EARLY NEXT WEEK LEADING TO A WARMING TREND AS WE MOVE INTO TUESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 215 PM EDT TUE APR 29 2014 SIMILAR TO YESTERDAY AFTERNOON...THERE REMAINS SOME UNCERTAINTY AS TO THE TIMING AND EXTENT OF THE CONVECTION THROUGH THE NIGHT. BEST INDICATIONS ARE THAT SHOWERS AND THUNDERSTORMS WILL DEVELOP AND MOVE BACK INTO THE AREA BETWEEN 23Z TO 01Z AND THEN FURTHER SATURATE THE LOW LEVELS ALLOWING FOR MVFR TO IFR CONDITIONS THROUGH THE REST OF THE OVERNIGHT TAF PERIOD. WINDS WILL BE GENERALLY OUT OF THE SOUTH AND SOUTHWEST THROUGH THE FIRST PART OF THE FORECAST INCREASING THROUGH THE FIRST PART OF THE NIGHT WITH GUSTS REACHING UP TO 25 KNOTS. THEY SHOULD THEN SETTLE SOMEWHAT FROM THE SOUTHWEST TO WEST INTO THE DAY WEDNESDAY AS CIGS AND VIS IMPROVE...BUT SHOWERS REMAIN AROUND. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
215 PM EDT TUE APR 29 2014 .UPDATE... ISSUED AT 200 PM EDT TUE APR 29 2014 FAR EASTERN KENTUCKY REMAINS MOSTLY CLOUDY AS CU HAS DEVELOPED WHERE THE CIRRUS THINNED. TO THE WEST...THOUGH...SKIES REMAIN CLEAR TO PARTLY SUNNY ALLOWING TEMPERATURES TO CLIMB INTO THE MID AND UPPER 70S. THIS WILL BE THE FUEL TO ANY STORMS THAT DEVELOP LATER THIS AFTERNOON AND INTO THE EVENING. THE HRRR STILL KEEPS THE CONVECTION OUT OF HERE THROUGH 00Z...BUT ALREADY A FEW PIN PRICK SHOWERS AND SPRINKLES ARE POPPING UP OVER EASTERN KENTUCKY INDICATING THAT CONVECTIVE TEMPERATURES ARE BEING REACHED. STILL EXPECT THE STRONGER STORMS TO HOLD OFF UNTIL CLOSER TO SUNSET...STARTING TO THE WEST IN RESPONSE TO THE APPROACHING MID LEVEL WAVE. THE LATEST MODEL SOUNDINGS ARE NOT QUITE A EXTREME AS THEY WERE EARLIER...BUT STILL INDICATE DECENT KEY INDICES FOR SEVERE WEATHER THROUGH MIDNIGHT. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST OBSERVATIONS/TRENDS AND SHIPPED THEM TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1050 AM EDT TUE APR 29 2014 14Z SFC ANALYSIS SHOWS A DEEP AND MATURE AREA OF LOW PRESSURE SPINNING OVER THE MISSOURI VALLEY WITH A WARM FRONT WELL NORTH OF EAST KENTUCKY. THE LATEST WAVE OF SHOWERS AND ISOLATED THUNDERSTORMS HAVE JUST ABOUT EXITED FAR EAST KENTUCKY...THOUGH THE LATEST HRRR DOES HOLD THEM IN THE FAR EAST FOR A FEW MORE HOURS. TEMPERATURES AT 10 AM VARY FRO THE LOW 60S WITH THE RAIN IN THE FAR EAST TO THE MIDDLE AND UPPER 60S IN THE WEST AND SOUTH WHERE THE CLOUDS ARE BREAKING UP. DEWPOINTS...MEANWHILE REMAIN IN THE UPPER 50S NORTHEAST TO THE LOWER 60S IN THE SOUTH. OF CRITICAL IMPORTANCE IS THE FADING OF THE HIGH CLOUDS THAT ACCOMPANIED THE LAST CONVECTIVE WAVE NOW EXITING. THESE ARE DISSOLVING FAST OVER THE WESTERN 2/3RDS OF THE CWA...JUSTIFYING OUR CONCERN FOR WARMER TEMPS AND HIGHER INSTABILITY BY LATE AFTERNOON AND EARLY EVENING. IN CONJUNCTION WITH THE APPROACH OF ANOTHER POTENT MID LEVEL WAVE BENEATH THE BASE OF A DEEP UPPER LEVEL LOW...THIS WOULD PROVIDE THE FUEL FOR THUNDERSTORM REDEVELOPMENT WITH SEVERE WEATHER A DISTINCT POSSIBILITY. THE STORMS THAT DEVELOP SHOULD FAVOR FORMING LINES AND BOWS WITH DAMAGING WINDS THE MAIN THREAT...BUT A FEW SUPERCELLS CANNOT BE RULED OUT ALONG WITH THE POTENTIAL FOR ISOLATED LARGE HAIL OR TORNADO OCCURRENCES. HAVE UPDATED THE GRIDS TO REFLECT THESE THOUGHTS... ALLOWING STORMS TO REDEVELOP JUST BEFORE 00Z IN THE WEST...A BLENDING OF THE 12Z NAM AND THE HRRR...AND GRADUALLY SLIDING EAST THROUGH THE NIGHT WITH ONE OR TWO ROUNDS OF CONVECTION POSSIBLE. DO EXPECT THE INSTABILITY TO BE WORKED OUT FOR MOST OF THE AREA BY MIDNIGHT OR SHORTLY THEREAFTER AND ANY LINGERING CONVECTION TO FOLLOW MORE SUBDUED. DID ALSO UPDATE THE T AND TD GRIDS TO BETTER MATCH UP WITH CURRENT OBS AND TRENDS. THESE UPDATES HAVE BEEN SENT WITH A ZONE AND SPS TOUCH UP TO FOLLOW. UPDATE ISSUED AT 730 AM EDT TUE APR 29 2014 UPDATED THE GRIDS TO INPUT THE LATEST OBS FOR TEMPS AND DEW POINTS. ALSO THE SHOWER ACTIVITY LOOKS TO BE ENDING FROM SOUTHWEST TO NORTHEAST AND ADJUSTED THE POPS TO ADDRESS THIS. OTHERWISE...THE CURRENT FORECAST IS STILL LOOKING GOOD TO GO AND WILL LET THE ZFP RIDE A BIT LONGER THIS MORNING. ANOTHER ASPECT IS APPARENT WITH THIS TREND...THE FIRST SIGNS OF CLEARING ARE BEGINNING TO OCCUR. WILL STRESS THIS TO THE DAY SHIFT AS THE THREAT OF SEVERE WEATHER IS LOOKING MORE LIKELY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 355 AM EDT TUE APR 29 2014 CURRENT CONDITIONS ACROSS EASTERN KENTUCKY FEATURE MAINLY SHOWERS CONTINUING TO STREAM NORTHEASTWARD INTO EASTERN KENTUCKY WITH A SLOW MOVING COLD FRONT OUT TO THE WEST. THIS ACTIVITY MOVING THROUGH EASTERN KENTUCKY IS MAINLY SUPPORTED BY THE LL JET MOVING NORTHEASTWARD AND MINIMAL INSTABILITY...IN FACT...HAVE SLIGHT CHANCE THUNDER THROUGH THE MORNING HOURS. THE PROBLEM HERE IS THE SHOWERS MOVING OVER THE SAME AREA IN THE SOUTHWEST AND ALL ALONG I-75. SOME SMALL FLOODING PROBLEMS MAY ARISE HEADING INTO THE MORNING HOURS AS MOISTURE CONTINUES TO STREAM NORTHEAST OUT OF CENTRAL TN. SO HAVE ISSUED AN URBAN AND SMALL STREAMS COVERING THE ROCKCASTLE... PULASKI...AND WAYNE COUNTY AREAS. SLOWLY BUT SURELY...THIS WEAKENED MCS WILL TRACK EASTWARD OUT OF EASTERN KENTUCKY LATER THIS MORNING BRINGING AN END TO THE MODERATE SHOWER ACTIVITY. MODELS SUGGEST THAT THE LINE OF SHOWERS WILL EXIT AND THERE STANDS THE CHANCE FOR SOME CLEARING IN THE WESTERN CWA. WILL KEEP THE CHANCE FOR SHOWERS AND THUNDERSTORMS THROUGH LATE MORNING WITH AT LEAST SOME GOOD CLOUD COVER DUE TO THE CONTINUED MOISTURE IN THE AREA AND UPPER LEVEL LIFT REMAINING IN THE VICINITY. THIS WILL AT LEAST HINDER THE ATMOSPHERE BECOMING UNSTABLE TODAY. WITH ALL THE RAIN TODAY AND SOME CLOUD COVER OVER THE AREA...KNOCKED DOWN HIGH TEMPS TODAY A FEW DEGREES...ESPECIALLY WITH MOS BEING A IN THE MID TO LOW 70S AND WENT ABOVE MOS A BIT TO THE UPPER 70S. KEEP IN MIND THAT IF...COMBINED WITH STRONG SOUTHERLY FLOW OF WARM MOIST AIR AND SOME CLEARING ALLOW TEMPS TO REACH THE LOW 80S...AN ACTIVE SEVERE WEATHER DAY MAY ENSUE BY THIS EVENING IN EARNEST. GETTING INTO THIS EVENING...THE COMPLEX UPPER LOW WILL CONTINUE TO SIT AND SPIN OVER THE NORTHERN MS RIVER VALLEY AS ANOTHER STRONG SHORTWAVE MOVES THROUGH THE BASE OF THE UPPER LEVEL TROUGH AND CONVERGES OVER THE MID MS RIVER VALLEY. THIS WILL PROVIDE ADDED UPPER LEVEL SUPPORT AS CONVECTION AND RENEWED SEVERE WEATHER WILL LIKELY BEGIN HERE AGAIN IN SOUTH CENTRAL TN...AND NORTHERN MS/AL. THIS ACTIVITY WILL THEN MOVE NORTH AS CONTINUED DEVELOPMENT BEGINS IN SOUTH CENTRAL KY AND MOVES EAST NORTHEAST. DUE TO THIS...WILL REINTRODUCE LIKELY TO DEFINITE POPS INTO THE WEST BY 00Z TONIGHT. THIS ROUND OF POSSIBLE SEVERE WEATHER WILL LAST THROUGH THE 00Z TO 06Z TONIGHT BEFORE THE GOOD INSTABILITY AND SHEAR MOVES EAST. WILL KEEP THE CHANCE OF PRECIP THROUGH THE NIGHT AND HAVE SHOWERS COMING TO AN END BY WEDNESDAY AFTERNOON AS THE BEST SUPPORT AND INSTABILITY EXITS EAST KENTUCKY. THOUGH...THE MODELS DO CONTINUE TO HAVE THE UPPER LOW STALLED OVER THE UPPER MS RIVER VALLEY SO THE CHANCE FOR SHOWERS MAY BECOME A DIURNALLY DRIVEN MECHANISM. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 448 AM EDT TUE APR 29 2014 THE MODELS START OUT IN VERY GOOD AGREEMENT WITH A STRONG POLAR VORTEX OVER SOUTHERN MINNESOTA WITH THE TROUGH AXIS EXTENDING SOUTH SOUTHWEST OVER OKLAHOMA. THERE IS A STRONG BLOCKING UPPER HIGH OVER THE WEST COAST. THE SURFACE FRONT SHOULD BE MOVING OUT OF EASTERN KENTUCKY AS THE PERIOD BEGINS WITH SURFACE RIDGING MOVING INTO THE AREA. BY FRIDAY MORNING...THE POLAR VORTEX MOVES TO THE NORTHEAST INTO CANADA WHERE IT BELONGS. AT THE SURFACE...THE HIGH CENTER WILL BE OVER EASTERN KENTUCKY. THE UPPER TROUGH AXIS IS SHIFTING TO THE SOUTHWEST. THE HARD PART OF THIS FORECAST IS TO TRY TO TIME ANY SHORT WAVES ACROSS THE AREA THAT MAY OR MAY NOT BE ABLE TO GENERATE ANY MEASURABLE SHOWERS. THE NEXT FRONT WILL MOVE ACROSS THE AREA ON MONDAY AS THE BLOCKING RIDGE AND STRONG LOW RECEDE AND ALLOW A MORE ZONAL PATTERN TO ESTABLISH ITSELF ACROSS THE CONUS. THE MODEL ARE HAVING A HARD TIME TRYING TO FIGURE OUT WHAT TO DO WITH THE RESIDUAL LOW/TROUGH OVER THE SOUTHWEST. THE ECMWF MOVES THE LOW SLOWLY ACROSS THE GULF COAST DURING THE PERIOD. USED TO MODEL BLEND BUT THEN NUDGED THE FORECAST 25 PERCENT TOWARD THE 00 GMT ECMWF. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 215 PM EDT TUE APR 29 2014 SIMILAR TO YESTERDAY AFTERNOON...THERE REMAINS SOME UNCERTAINTY AS TO THE TIMING AND EXTENT OF THE CONVECTION THROUGH THE NIGHT. BEST INDICATIONS ARE THAT SHOWERS AND THUNDERSTORMS WILL DEVELOP AND MOVE BACK INTO THE AREA BETWEEN 23Z TO 01Z AND THEN FURTHER SATURATE THE LOW LEVELS ALLOWING FOR MVFR TO IFR CONDITIONS THROUGH THE REST OF THE OVERNIGHT TAF PERIOD. WINDS WILL BE GENERALLY OUT OF THE SOUTH AND SOUTHWEST THROUGH THE FIRST PART OF THE FORECAST INCREASING THROUGH THE FIRST PART OF THE NIGHT WITH GUSTS REACHING UP TO 25 KNOTS. THEY SHOULD THEN SETTLE SOMEWHAT FROM THE SOUTHWEST TO WEST INTO THE DAY WEDNESDAY AS CIGS AND VIS IMPROVE...BUT SHOWERS REMAIN AROUND. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...SHALLENBERGER LONG TERM...JJ AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
156 PM EDT TUE APR 29 2014 .UPDATE... ISSUED AT 1153 AM EDT TUE APR 29 2014 ...ADVISORY ISSUED FOR NEAR TERM TRAVEL HAZARDS... BASED ON NUMEROUS REPORTS OF ACCIDENTS AND WEBCAMS CONFIRMING THAT SNOW IS ACCUMULATING ON ROADWAYS OVER THE HIGHER TERRAIN /~1500 FT/ WILL ISSUE A SHORT FUSED WINTER WEATHER ADVISORY TO COVER THE TRAVEL HAZARD THROUGH EARLY AFTERNOON. THE IMPACTS WILL BE COMPLETELY TIED TO PRECIPITATION RATES...AND WITH THE BACK EDGE OF RETURNS ALREADY PULLING NORTH THROUGH MENOMINEE COUNTY...THIS PROVIDED A PRETTY SHORT WINDOW FOR ACCUMULATING SNOW. STILL 2-4" IS LIKELY OVER THE HIGH TERRAIN BEFORE PRECIPITATION TAPERS TO DRIZZLE. UPDATE ISSUED AT 954 AM EDT TUE APR 29 2014 ...QUICK BURST OF SNOW THIS MORNING AS PRECIPITATION ARRIVES... BASED ON MORNING SPOTTER REPORTS AND AREA WEBCAMS...HAVE BOOSTED SNOW TOTALS SLIGHTLY AS PRECIPITATION IS ARRIVING AS A BURST OF SNOW FOR AREAS FROM MARQUETTE SOUTH AND WEST. DUAL POL VARIABLES FROM THE KMQT-88D SUGGEST A GROWING SURFACE-BASED WARM LAYER AT MQT...AND DO EXPECT A PRETTY STEADY TRANSITION TO RAIN FROM EAST TO WEST DURING THE MORNING...WITH THIS CHANGEOVER NOT REACHING AREAS FROM ONTONAGON TO IRONWOOD UNTIL LATE AFTERNOON...BY WHICH TIME THE HEAVIEST BAND OF PRECIPITATION WILL BE BEGINNING TO LIFT NORTH OF THE REGION. ISSUED A SPS TO HANDLE QUICK BURST OF SNOW...AND MAY DO SO ONCE MORE FOR WESTERN ZONES AS PRECIPITATION ARRIVES HERE. DID SLOW PRECIPITATION ARRIVAL JUST A TAD BASED ON MORNING RADAR EVOLUTION...BUT NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 520 AM EDT TUE APR 29 2014 WV IMAGERY AND RUC ANALYSIS REVEALS REX BLOCK PATTERN OVER THE CENTRAL PORTION OF NORTH AMERICA WITH A HIGH OVER HUDSON BAY AND AN OCCLUDING CLOSED LOW OVER THE IOWA/MISSOURI BORDER. AT THE SFC...A FEW SITES WERE REPORTING GUSTY EAST TO NORTHEAST WINDS AS A RESULT OF A TIGHT PRES GRADIENT BETWEEN STRONG HIGH PRES OVER HUDSON BAY AND A LOW OVER NW MISSOURI. BOTH KCMX AND KMNM WERE REPORTING WIND GUSTS TO NEAR 40 MPH AT TIMES EARLY THIS MORNING. A BAND OF RAIN OVER NORTHERN LAKE MI AND SE UPPER MI SUPPORTED BY 295K-300K ISENTROPIC ASCENT WAS MAKING VERY SLOW NORTHWARD PROGRESS AS IT ENCOUNTERS DRY EASTERLY FLOW (BELOW 750 MB) TO THE NORTH AND EAST...PER 00Z APX SOUNDING. AS THE MID LEVEL LOW WOBBLES TO THE NORTHEAST AND A SHORTWAVE LIFTS NORTH INTO UPPER MI...INCREASING 295K ISENTROPIC ASCENT WILL FINALLY OVERCOME LOW-LVL DRY AIR AND ALLOW PCPN TO SPREAD FROM SCNTRL/SE CWA NORTH AND WEST ACROSS THE REST OF WEST AND CENTRAL UPPER MI LATER THIS MORNING AND AFTERNOON. THE PCPN IS EXPECTED TO TAPER OFF FROM SSE TO NNW BY MID TO LATE AFTERNOON. THE HEAVIER PCPN WILL COINCIDE WITH TROWAL REGION NORTH OF THE MID/UPPER LOW AS NOTED ON MODELS 310-320 THETA-E LAYER. ALTHOUGH MOST AREAS SHOULD SEE QPF AMOUNTS IN THE 0.50 TO .75 INCH RANGE...THE STRONGEST LIFT AND MOISTURE INFLOW IS EXPECTED OVER THE SE CWA WHERE QPF COULD EXCEED AN INCH THROUGH TONIGHT. UPSLOPE NE FLOW INTO N CNTRL UPPER MI COULD ALSO SUPPORT RELATIVELY HIGHER PCPN AMOUNTS THERE. SOME UNCERTAINTY REMAINS WITH THE PCPN TYPE OVER THE HIGHER TERRAIN OF THE WRN HALF OF UPPER MI. THE 12Z NAM LOW LEVEL THICKNESS AND WET- BULB ZERO HEIGHTS SUGGEST THAT SNOW MAY BE THE PREDOMINATE PCPN TYPE OVER THE WRN INTERIOR THIS MORNING...AND ESPECIALLY OVER THE HIGHER TERRAIN OF THE FAR WEST TOWARD IWD. EVEN WITH THE HIGH QPF AMOUNTS...VERY LOW SLR VALUES AND RELATIVELY WARM ROAD SURFACES SHOULD MINIMIZE SNOW ACCUMULATION TO AN INCH OR MAYBE TWO TOWARD KIWD WITH MOST ACCUMULATION ON GRASSY OR SNOW COVERED AREAS. WITH MODELS SHOWING SHORTWAVE AND ASSOC TROWAL REGION LIFTING NORTH AND WEST OF THE FCST AREA TONIGHT ALONG WITH CORRESPONDING WEAKENING OF ISENTROPIC ASCENT AND TRANSITION TO MID-LVL Q-VECT DIVERGENCE... LOOK FOR HEAVIER PCPN TO TAPER OFF AND BECOME MORE LIGHT AND SCATTERED WITH MOST LOCATIONS SEEING BTWN .1 TO .2 INCH. WITH WARMING LOW-LVLS AS NOTED ON SOUNDINGS AND RISING 1000-850 MB THICKNESSES WOULD EXPECT PTYPE MOSTLY RAIN TONIGHT. AREA RIVERS AND STREAMS WILL NEED TO BE MONITORED CLOSELY OVER THE NEXT SEVERAL DAYS AS RUNOFF FROM PCPN AND SNOWMELT WILL LEAD TO RISING RIVER LEVELS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 501 AM EDT TUE APR 29 2014 THE BEGINNING OF THE LONG TERM PERIOD CONTINUES TO BE DOMINATED BY THE UPPER LOW CURRENTLY OVER THE CENTRAL CONUS. BY 12Z WED...THE UPPER LOW WILL CENTERED ALONG THE MN/WI BORDER AND WILL WOBBLE E TO NEAR ERN WI BY 12Z THU BEFORE MOVING E OF THE CWA BY 00Z FRI. WITH THE UPPER LOW TO THE SW/S AND A WEAK SFC LOW S/SE OF THE CWA WED THROUGH THU...LIGHT RAIN IS EXPECTED BOTH DAYS ACROSS MOST OF THE CWA. MODELS INDICATE PIECES OF ENERGY ROTATING AROUND THE UPPER LOW AND THROUGH THE CWA...WHICH WILL LEAD TO PERIODS OF HEAVIER PRECIP AND GREATER COVERAGE...FOLLOWED BY PERIODS OF LIGHTER PRECIP WITH LESSER COVERAGE. GIVEN UNCERTAINTY WITH EXACT TIMING/MAGNITUDE OF ADDITIONAL ENERGY...BROAD BRUSHED POPS WILL COVER THINGS AT THIS POINT...WITH MORE ENHANCEMENT NEEDED BY LATER SHIFTS. WARM NOSE CENTERED AROUND 850MB WILL KEEP PRECIP AS RAIN FROM 12Z WED THROUGH MOST OF WED NIGHT UNTIL COLDER AIR MOVES IN BEHIND THE UPPER LOW. ANY MIXED PRECIP OR SNOW FOR THE REST OF THU WILL BE CONFINED TO THE HIGHER TERRAIN OF NWRN UPPER MI AS ABOVE 0C TEMPS WILL BE CLOSER TO THE SFC AND CONFINED MORE TO THE LOWER TERRAIN AND ERN CWA. CONTINUED TO USE MODELED WET BULB ZERO HEIGHTS AND 1000-850MB THICKNESS FOR PTYPES. CONFIDENCE IN THE REST OF THE FORECAST PERIOD IS LOWER AS MODEL AGREEMENT IS POOR. IN GENERAL...UPPER TROUGHING WITH MORE SUBTLE EMBEDDED PIECES OF ENERGY IS SHOWN OVER THE NCENTRAL CONUS FRI INTO SUN...RESULTING IN CONTINUED COLD AND WET CONDITIONS...BUT WITH LESSER QPF AMOUNTS THAT WHAT WE WILL SEE TODAY INTO WED. MODELS THEN SHOW ZONAL OR WEAK RIDGING DEVELOPING SUN INTO EARLY NEXT WEEK...WHICH SHOULD LEAD TO DRIER CONDITIONS AND EVENTUALLY WARMER && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 155 PM EDT TUE APR 29 2014 ...OVERALL IFR CONDITIONS THROUGH WEDNESDAY 18Z... BATCH OF WIDESPREAD PRECIPITATION (MAINLY SNOW) IN THE PROCESS OF WORKING UP THROUGH WESTERN UPPER MICHIGAN THIS AFTERNOON...LEADING TO SOLID IFR CONDITIONS AT THE TERMINAL SITES. HOWEVER...SRN BACK EDGE OF PRECIPITATION ALREADY IN THE PROCESS OF ADVANCING INTO THE UPPER PENINSULA AND EXPECT PRECIP TO TAPER OFF QUICKLY OVER THE NEXT 1 TO 3 HOURS. BUT...ABUNDANT LOW CLOUDS (SUB 1K FEET) AND PERHAPS A LITTLE BIT OF DRIZZLE WILL REMAIN THROUGH THE BALANCE OF THE AFTERNOON AND EVEN THROUGH TONIGHT WITH IFR CONDITIONS LIKELY REMAINING DOMINANT. LATER THIS EVENING...ANOTHER BATCH OF RAIN SHOWERS FORMING OVER SRN WISCONSIN/CHICAGO LOOKING TO ROTATE UP INTO WESTERN UPPER MICHIGAN AND LOOKING TO BRING ANOTHER PERIOD OF MORE WIDESPREAD SHOWERS (MAINLY RAIN ANTICIPATED) LATER THIS EVENING AND OVERNIGHT. BUT EXACT TIMING OF SHOWERS IS A BIT UNCERTAIN AT THIS POINT AND HAVE JUST GENERIC SHRADZ FOR THE TERMINAL SITES. ADDITIONAL SHOWERS ANTICIPATED ON TUESDAY. POSSIBLE CIGS/VSBYS MAY TRY TO NUDGE UP TO MVFR BY MIDDAY TUESDAY...BUT WILL KEEP THE FORECAST ON THE PESSIMISTIC IFR SIDE OF THINGS FOR NOW. WINDS...NORTHEAST AND GUSTY THROUGH LATE AFTERNOON...BUT WILL DIMINISH TO UNDER 10 KNOTS THIS EVENING THROUGH TUESDAY AS THE STACKED LOW PRESSURE SYSTEM INCHES INTO THE WESTERN GREAT LAKES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 520 AM EDT TUE APR 29 2014 AS A RESULT OF THE STRONG PRES GRADIENT BTWN A DEEP LOW OVER CENTRAL PLAINS AND THE STRONG HIGH OVER HUDSON BAY EAST TO NORTHEAST GALES ARE EXPECTED TO CONTINUE OVER THE WRN PORTION OF LAKE SUPERIOR THROUGH TUE EVENING. THESE WINDS WILL ALSO BE ENHANCED BY CHANNELING BETWEEN THE KEWEENAW PENINSULA AND ISLE ROYALE. A FEW ENE GALE FORCE GUSTS TO 35 KNOTS ARE ALSO POSSIBLE OVER CENTRAL LAKE SUPERIOR MAINLY THIS MORNING BUT SUSTAINED GALES ARE NOT EXPECTED SO WATCH HEADLINE HAS BEEN DROPPED. THE WINDS WILL DIMINISH THIS EVENING AS THE LOW LIFTS TO THE NORTH TOWARD THE WRN GREAT LAKES AND THE PRES GRADIENT WEAKENS. HOWEVER WINDS TO 30 KNOTS ARE STILL EXPECTED UNTIL LATE TUE NIGHT. WINDS ARE EXPECTED TO DROP OFF TO 25 KNOTS OR LESS FROM WED && .HYDROLOGY... ISSUED AT 501 AM EDT TUE APR 29 2014 RUNOFF FROM RECENT SNOWMELT AND RAINFALL CONTINUES TO FLOW THROUGH THE GROUND...SO DESPITE THE RECENT COOLER WEATHER...SOME AREA STREAMS AND RIVERS REMAIN HIGH. LOCATIONS THAT ARE STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE STURGEON RIVER NEAR CHASSELL...THE PAINT RIVER NEAR CRYSTAL FALLS AND THE STURGEON RIVER NEAR NAHMA JUNCTION. AT LEAST THROUGH TONIGHT THESE RIVERS ARE NOT EXPECTED TO REACH FLOOD STAGE...BUT THESE AND OTHER RIVERS WILL START TO RISE AGAIN TONIGHT AND WEDNESDAY DUE TO A LOW PRESSURE SYSTEM AND WIDESPREAD PRECIPITATION AFFECTING UPPER MICHIGAN. TOTAL LIQUID EQUIVALENT PRECIPITATION AMOUNTS COULD REACH 1 TO 2 INCHES BY THURSDAY. THE PRECIPITATION WOULD ADD TO THE FLOOD RISK. WHILE WIDESPREAD AND AREAL FLOODING IS NOT EXPECTED...RFC ENSEMBLE FORECASTS DO SHOW SIGNIFICANT RISES ON A FEW OF THE RIVERS IF HIGHER QPF FROM THE MODELS VERIFIES. THE MOST UNCERTAINTY EXISTS OVER THE RIVERS OF NORTHWEST UPPER MI...PARTICULARLY THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER. THESE RIVERS STILL HAVE A FEW INCHES OF SNOW WATER EQUIVALENT IN THEIR BASINS AND IT IS UNKNOWN EXACTLY HOW MUCH MELTING OF THAT SNOWPACK WILL OCCUR WITH THE PRECIPITATION /WHICH WILL FALL AS WET SNOW FOR THE MOST PART TODAY AND ALL RAIN TONIGHT AND WEDNESDAY/. WILL CONTINUE TO MONITOR THESE AREAS ESPECIALLY CLOSE. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD MONITOR RIVER LEVELS THIS WEEK. REPORTS INDICATE LITTLE ICE REMAINS ON AREA RIVERS...SO THE ICE JAM FLOODING THREAT HAS GREATLY DIMINISHED. THE ONLY EXCEPTION MIGHT BE AT THE MOUTHS OF RIVERS THAT FLOW INTO THE GREAT LAKES WHERE && .MQT WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR MIZ002-004-005-009>011-084. LS...GALE WARNING UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR LSZ162- 263-264. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ221-248- 250. && $$ UPDATE...ARNOTT/APX SHORT TERM...VOSS LONG TERM...TITUS AVIATION...ADAM HYDROLOGY...TITUS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS DULUTH MN
432 PM CDT TUE APR 29 2014 .UPDATE... ISSUED AT 430 PM CDT TUE APR 29 2014 HAVE INCREASED SNOWFALL AMOUNTS THIS EVENING FOR THE TWIN PORTS AND I-35 CORRIDOR. THE SNOW WILL BE LOCALIZED WITH SOME AREAS SEEING LITTLE OR NO SNOW. HOWEVER...AREAS THAT DO SEE SNOW CAN EXPECT 1-3" OF ACCUMULATION. SNOWFALL SPOTTERS ARE REPORTING LOCALIZED HEAVY SNOW WITHIN A FEW OF THE SHOWERS. && .SHORT TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 311 PM CDT TUE APR 29 2014 AT 300PM/2000Z...THERE WAS A LARGE LOW PRESSURE SYSTEM CENTERED OVER EASTERN IOWA. HIGH PRESSURE WAS CENTERED OVER HUDSON BAY AND QUEBEC. MUCH OF THE UPPER MIDWEST HAD RAIN AND SNOW SHOWERS AND CLOUDY SKIES...WHILE THE NORTHERN PLAINS OF NW MINNESOTA AND NORTH DAKOTA HAD CLEAR SKIES DUE TO THE INFLUENCE OF THE CANADIAN HIGH PRESSURE. THERE WAS LIGHT TO MODERATE RAIN AND SNOW IN NW WISCONSIN ASSOCIATED WITH THE LOW PRESSURE SYSTEM...AND WHICH WAS GRADUALLY MOVING WEST AND NORTHWARD INTO THE CENTRAL FORECAST AREA. THE BAND OF RAIN AND SNOW WAS ALSO ASSOCIATED WITH A SHORTWAVE OVER WESTERN WISCONSIN SHIFTING TO THE NORTH AND WEST. TEMPERATURES RANGED FROM THE LOW 30S IN NW WISCONSIN AND THE UPPER 30S TO NEAR 50 DEGREES IN NE MINNESOTA. THE CONCERN FOR THIS EVENING IS THE CURRENT MAIN BAND OF SNOW SHOWERS IN NW WISCONSIN...AND HOW IT WILL AFFECT OTHER AREAS AS IT MOVES WEST. IN THIS MAIN BAND OF MAXIMIZED OMEGA...SNOW IS FALLING FROM ALOFT AND AT FALLING AS RAIN AT FIRST ALONG ITS WESTERN LEADING EDGE. THEN THE TEMPERATURES NEAR THE SURFACE ARE FALLING...AND ALLOWING THE PCPN TO SWITCH FROM RAIN TO SNOW NEAR THE SURFACE. THE RELATIVELY WARM SURFACE IS MAKING IT TAKE SOME TIME FOR SNOW TO ACCUMULATE...ESPECIALLY ON THE ROADS. WE HAVE GOTTEN PLENTY OF REPORTS THOUGH THAT THE SNOW IS EVENTUALLY ACCUMULATING ON GRASS AND ROOFS AND SUCH...AND CREATING SLUSHY ROADS. VISIBILITY IS ALSO LOW AT TIMES DURING THE HEAVIER SNOW RATES. THIS BAND WILL BE SHIFTING INTO AREAS OF THE CENTRAL AND WESTERN FORECAST AREA THAT HAVE GOTTEN MUCH WARMER THAN NW WISCONSIN GOT TODAY DUE TO NW WISCONSIN BEING WET AND CLOUDY FOR MOST OF TODAY...WHILE WESTERN AREAS REMAINED DRY. THEREFORE...I THINK IT WILL TAKE EXTRA TIME FOR THE PCPN TO SWITCH TO SNOW AND FOR THE SNOW TO ACCUMULATE AS IT MOVES INTO THE WESTERN FORECAST AREA. HOWEVER...AREAS COULD SEE UP TO A COUPLE INCHES OF SNOW ACCUMULATION. IF THE SNOW LINGERS LONG ENOUGH AND/OR FALLS HEAVY ENOUGH...ACCUMULATION COULD BE GREATER. AT THIS POINT WE HAVE BEEN COVERING THIS SYSTEM WITH NOWCASTS DUE TO SNOW ACCUMULATION BEING LESS THAN 3 INCHES...BUT WE MIGHT NEED TO RECONSIDER A WINTER WEATHER ADVISORY IF SNOWFALL AMOUNTS APPEAR TO BE MORE THAN FORECAST. THE HRRR HAS BEEN DOING FAIRLY WELL DEPICTING THE TIMING OF THIS BAND OF RAIN AND SNOW...SO I LEANED ON THAT MODEL FOR MY HOURLY FORECAST THROUGH TONIGHT. IT APPEARS THAT HUMIDITY IN THE ICE NUCLEATION LAYER COULD DRY UP FOR A TIME TONIGHT IN THE WAKE OF THE BAND OF PCPN...SO PCPN COULD SWITCH FROM SNOW/RAIN TO DRIZZLE FOR A PERIOD. HOWEVER...IT THEN APPEARS SATURATION IN THE ICE NUCLEATION LAYER WILL INCREASE AGAIN LATE TONIGHT. THIS IS WHY I HAVE BOTH RAIN AND SNOW IN THE FORECAST FOR MOST THE FORECAST AREA ALL THE WAY THROUGH TONIGHT. SURFACE TEMPERATURES ARE FORECAST TO PRIMARILY BE JUST ABOVE FREEZING TONIGHT...SO I DID NOT PUT ANY FREEZING RAIN IN THE FORECAST. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 311 PM CDT TUE APR 29 2014 TIS THE SEASON...FOR ATMOSPHERIC BLOCKS THAT IS...AND THE LARGE CLOSED LOW OVER EASTERN IOWA IS TAKING CENTER STAGE. MDLS DISPLAY STRONG CONSENSUS THAT MID LVL FEATURE WILL MEANDER INTO SRN MN BY WED MORNING...AND THEN SLIDE EAST TOWARDS NRN IL BY THUR MORNING. AS THIS OCCURS...A LARGE DEEP AND MOIST CIRCULATION WILL ENCOMPASS THE ENTIRE REGION. AS EXPRESSED IN PREVIOUS DISCUSSIONS THIS TYPE OF SYNOPTIC PATTERN WILL GUARANTEE HIGH AMOUNTS OF CLOUD COVER HOWEVER THE SKILL LEVEL FOR POPS IS RATHER LIMITED. CHARACTERISTICALLY THIS TYPE OF SYSTEM WOULD EXHIBIT HIGHER POPS DIURNALLY WITH DAYTIME CONVECTION AND MIN POPS IN THE OVERNIGHT. HOWEVER GIVEN THE EXTENSIVE CLOUD CANOPY THE AMOUNT OF DIURNAL INSTABILITY WILL BE LIMITED. THIS LEAVES THE POTENTIAL FOR PRECIP TO BE MORE ALIGNED WITH MIGRATORY SHORTWAVE FEATURES ALOFT. WILL USE A HIGH POP/LOW QPF THEME THROUGH MID DAY THURSDAY. MDLS LIFT SYSTEM EAST FRIDAY AS AN UPSTREAM KICKER ARRIVES EMBEDDED WITHIN THE NW FLOW. WHILE THIS SYSTEM WILL ACT TO IMPROVE THE WEATHER INITIALLY IT WILL EVENTUALLY AMPLIFY OVERHEAD SATURDAY WHICH MAY LEAD TO AN INCREASE IN POPS FOR THE NRN TIER OF ZONES. THERE DOES APPEAR TO BE A MDT TO HIGH PROBABILITY THAT FAIR WX MAY RETURN BY SUNDAY AND CONTINUE INTO NEXT WEEK BASED ON THE MID LVL FLOW WHICH ESTABLISHES RIDGING ALOFT OVER THE NRN PLAINS. TEMPS BLO LIMO THROUGH THE WEEK...AND THEN AIMING FOR NEAR SEASONAL VALUES EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1240 PM CDT TUE APR 29 2014 MAIN ITEM OF INTEREST IS AREA OF MDT/HEAVY SNOW ASSOCIATED WITH OMEGA/DGZ CROSSING WISC ZONES EARLY THIS AFTERNOON. THIS FORCING WILL ADVECT INTO KDLH BY 19Z AND PERSIST THROUGH LATE AFTERNOON. INITIAL PTYPE OF RASN SHOULD TRANSITION QUICKLY ONCE VERTICAL MOTION INCREASES. OTHERWISE GUSTY WINDS WILL CONTINUE THROUGH THE AFTN AND EARLY EVENING HRS. CEILINGS WILL LOWER THROUGH THE PERIOD AS MID LVL LOW MOVES INTO SERN MN AND SATURATION DEEPENS WITHIN THE CYCLONIC CIRCULATION. && .PRELIMINARY POINT TEMPS/POPS... DLH 32 41 36 44 / 100 80 70 60 INL 34 44 36 49 / 90 80 70 50 BRD 35 45 38 48 / 90 80 70 40 HYR 35 46 37 47 / 80 80 70 60 ASX 34 40 35 43 / 90 80 70 60 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT WEDNESDAY FOR LSZ121-140>148. && $$ UPDATE...GRANING SHORT TERM...GROCHOCINSKI LONG TERM...CANNON AVIATION...CANNON
AREA FORECAST DISCUSSION
NWS DULUTH MN
312 PM CDT TUE APR 29 2014 .SHORT TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 311 PM CDT TUE APR 29 2014 AT 300PM/2000Z...THERE WAS A LARGE LOW PRESSURE SYSTEM CENTERED OVER EASTERN IOWA. HIGH PRESSURE WAS CENTERED OVER HUDSON BAY AND QUEBEC. MUCH OF THE UPPER MIDWEST HAD RAIN AND SNOW SHOWERS AND CLOUDY SKIES...WHILE THE NORTHERN PLAINS OF NW MINNESOTA AND NORTH DAKOTA HAD CLEAR SKIES DUE TO THE INFLUENCE OF THE CANADIAN HIGH PRESSURE. THERE WAS LIGHT TO MODERATE RAIN AND SNOW IN NW WISCONSIN ASSOCIATED WITH THE LOW PRESSURE SYSTEM...AND WHICH WAS GRADUALLY MOVING WEST AND NORTHWARD INTO THE CENTRAL FORECAST AREA. THE BAND OF RAIN AND SNOW WAS ALSO ASSOCIATED WITH A SHORTWAVE OVER WESTERN WISCONSIN SHIFTING TO THE NORTH AND WEST. TEMPERATURES RANGED FROM THE LOW 30S IN NW WISCONSIN AND THE UPPER 30S TO NEAR 50 DEGREES IN NE MINNESOTA. THE CONCERN FOR THIS EVENING IS THE CURRENT MAIN BAND OF SNOW SHOWERS IN NW WISCONSIN...AND HOW IT WILL AFFECT OTHER AREAS AS IT MOVES WEST. IN THIS MAIN BAND OF MAXIMIZED OMEGA...SNOW IS FALLING FROM ALOFT AND AT FALLING AS RAIN AT FIRST ALONG ITS WESTERN LEADING EDGE. THEN THE TEMPERATURES NEAR THE SURFACE ARE FALLING...AND ALLOWING THE PCPN TO SWITCH FROM RAIN TO SNOW NEAR THE SURFACE. THE RELATIVELY WARM SURFACE IS MAKING IT TAKE SOME TIME FOR SNOW TO ACCUMULATE...ESPECIALLY ON THE ROADS. WE HAVE GOTTEN PLENTY OF REPORTS THOUGH THAT THE SNOW IS EVENTUALLY ACCUMULATING ON GRASS AND ROOFS AND SUCH...AND CREATING SLUSHY ROADS. VISIBILITY IS ALSO LOW AT TIMES DURING THE HEAVIER SNOW RATES. THIS BAND WILL BE SHIFTING INTO AREAS OF THE CENTRAL AND WESTERN FORECAST AREA THAT HAVE GOTTEN MUCH WARMER THAN NW WISCONSIN GOT TODAY DUE TO NW WISCONSIN BEING WET AND CLOUDY FOR MOST OF TODAY...WHILE WESTERN AREAS REMAINED DRY. THEREFORE...I THINK IT WILL TAKE EXTRA TIME FOR THE PCPN TO SWITCH TO SNOW AND FOR THE SNOW TO ACCUMULATE AS IT MOVES INTO THE WESTERN FORECAST AREA. HOWEVER...AREAS COULD SEE UP TO A COUPLE INCHES OF SNOW ACCUMULATION. IF THE SNOW LINGERS LONG ENOUGH AND/OR FALLS HEAVY ENOUGH...ACCUMULATION COULD BE GREATER. AT THIS POINT WE HAVE BEEN COVERING THIS SYSTEM WITH NOWCASTS DUE TO SNOW ACCUMULATION BEING LESS THAN 3 INCHES...BUT WE MIGHT NEED TO RECONSIDER A WINTER WEATHER ADVISORY IF SNOWFALL AMOUNTS APPEAR TO BE MORE THAN FORECAST. THE HRRR HAS BEEN DOING FAIRLY WELL DEPICTING THE TIMING OF THIS BAND OF RAIN AND SNOW...SO I LEANED ON THAT MODEL FOR MY HOURLY FORECAST THROUGH TONIGHT. IT APPEARS THAT HUMIDITY IN THE ICE NUCLEATION LAYER COULD DRY UP FOR A TIME TONIGHT IN THE WAKE OF THE BAND OF PCPN...SO PCPN COULD SWITCH FROM SNOW/RAIN TO DRIZZLE FOR A PERIOD. HOWEVER...IT THEN APPEARS SATURATION IN THE ICE NUCLEATION LAYER WILL INCREASE AGAIN LATE TONIGHT. THIS IS WHY I HAVE BOTH RAIN AND SNOW IN THE FORECAST FOR MOST THE FORECAST AREA ALL THE WAY THROUGH TONIGHT. SURFACE TEMPERATURES ARE FORECAST TO PRIMARILY BE JUST ABOVE FREEZING TONIGHT...SO I DID NOT PUT ANY FREEZING RAIN IN THE FORECAST. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 311 PM CDT TUE APR 29 2014 TIS THE SEASON...FOR ATMOSPHERIC BLOCKS THAT IS...AND THE LARGE CLOSED LOW OVER EASTERN IOWA IS TAKING CENTER STAGE. MDLS DISPLAY STRONG CONSENSUS THAT MID LVL FEATURE WILL MEANDER INTO SRN MN BY WED MORNING...AND THEN SLIDE EAST TOWARDS NRN IL BY THUR MORNING. AS THIS OCCURS...A LARGE DEEP AND MOIST CIRCULATION WILL ENCOMPASS THE ENTIRE REGION. AS EXPRESSED IN PREVIOUS DISCUSSIONS THIS TYPE OF SYNOPTIC PATTERN WILL GUARANTEE HIGH AMOUNTS OF CLOUD COVER HOWEVER THE SKILL LEVEL FOR POPS IS RATHER LIMITED. CHARACTERISTICALLY THIS TYPE OF SYSTEM WOULD EXHIBIT HIGHER POPS DIURNALLY WITH DAYTIME CONVECTION AND MIN POPS IN THE OVERNIGHT. HOWEVER GIVEN THE EXTENSIVE CLOUD CANOPY THE AMOUNT OF DIURNAL INSTABILITY WILL BE LIMITED. THIS LEAVES THE POTENTIAL FOR PRECIP TO BE MORE ALIGNED WITH MIGRATORY SHORTWAVE FEATURES ALOFT. WILL USE A HIGH POP/LOW QPF THEME THROUGH MID DAY THURSDAY. MDLS LIFT SYSTEM EAST FRIDAY AS AN UPSTREAM KICKER ARRIVES EMBEDDED WITHIN THE NW FLOW. WHILE THIS SYSTEM WILL ACT TO IMPROVE THE WEATHER INITIALLY IT WILL EVENTUALLY AMPLIFY OVERHEAD SATURDAY WHICH MAY LEAD TO AN INCREASE IN POPS FOR THE NRN TIER OF ZONES. THERE DOES APPEAR TO BE A MDT TO HIGH PROBABILITY THAT FAIR WX MAY RETURN BY SUNDAY AND CONTINUE INTO NEXT WEEK BASED ON THE MID LVL FLOW WHICH ESTABLISHES RIDGING ALOFT OVER THE NRN PLAINS. TEMPS BLO LIMO THROUGH THE WEEK...AND THEN AIMING FOR NEAR SEASONAL VALUES EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1240 PM CDT TUE APR 29 2014 MAIN ITEM OF INTEREST IS AREA OF MDT/HEAVY SNOW ASSOCIATED WITH OMEGA/DGZ CROSSING WISC ZONES EARLY THIS AFTERNOON. THIS FORCING WILL ADVECT INTO KDLH BY 19Z AND PERSIST THROUGH LATE AFTERNOON. INITIAL PTYPE OF RASN SHOULD TRANSITION QUICKLY ONCE VERTICAL MOTION INCREASES. OTHERWISE GUSTY WINDS WILL CONTINUE THROUGH THE AFTN AND EARLY EVENING HRS. CEILINGS WILL LOWER THROUGH THE PERIOD AS MID LVL LOW MOVES INTO SERN MN AND SATURATION DEEPENS WITHIN THE CYCLONIC CIRCULATION. && .PRELIMINARY POINT TEMPS/POPS... DLH 32 41 36 44 / 90 80 70 60 INL 34 44 36 49 / 90 80 70 50 BRD 35 45 38 48 / 80 80 70 40 HYR 35 46 37 47 / 70 80 70 60 ASX 34 40 35 43 / 70 80 70 60 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-140>148. && $$ SHORT TERM...GROCHOCINSKI LONG TERM...CANNON AVIATION...CANNON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
144 PM EDT TUE APR 29 2014 .SYNOPSIS... HIGH PRESSURE WILL BRING DRY WEATHER THROUGH MOST OF TODAY. A LARGE AREA OF LOW PRESSURE ACROSS THE CENTRAL UNITED STATES WILL GRADUALLY SHIFT EASTWARD. THIS SYSTEM WILL BRING INCREASINGLY BREEZY CONDITIONS TODAY...FOLLOWED BY PERIODS OF RAIN...ESPECIALLY WEDNESDAY THROUGH THURSDAY MORNING. RAIN MAY BE HEAVY AT TIMES WEDNESDAY NIGHT. TEMPERATURES WILL REMAIN SLIGHTLY BELOW SEASONAL AVERAGES THROUGH THE END OF THE WEEK. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... AS OF 1247 PM EDT TUESDAY...DRIER AIR FROM THE EAST HAS PUSHED ACROSS MUCH OF CENTRAL AND NORTHERN VERMONT RESULTING IN MOSTLY SUNNY CONDITIONS THROUGH FILTERED HIGH CLOUDINESS. HAVE MADE SOME ADJUSTMENTS TO SKY COVER THROUGH THIS AFTERNOON BASED ON CURRENT CONDITIONS AND RUC RH PROFILES. MEANWHILE...FRONTAL RAINBAND IS APPROACHING SOUTHWESTERN ST. LAWRENCE COUNTY NY...WITH LIGHT RAIN DEVELOPING ACROSS FAR SWRN PORTIONS OF THE COUNTY LATE THIS AFTN. MINOR ADJUSTMENTS MADE TO POPS ACROSS ST. LAWRENCE COUNTY TO ACCOUNT FOR RADAR TRENDS AT THIS TIME...BUT OVERALL FORECAST IS ON TRACK. BROAD DEEP-LAYER LOW PRESSURE SYSTEM AFFECTING MUCH OF THE CENTRAL AND MIDWEST U.S. WILL GRADUALLY HAVE AN INCREASING INFLUENCE ON OUR WEATHER OVER THE COMING DAYS. MEANWHILE...IT LOOKS LIKE MOST OF THE FORECAST AREA WILL SEE ONE MORE DRY DAY TODAY BEFORE THE WET WEATHER ARRIVES. SURFACE RIDGE AXIS ACROSS NEW ENGLAND THIS MORNING WILL SHIFT SLOWLY EASTWARD INTO THE GULF OF MAINE BY THIS EVENING AND GENERALLY REMAIN IN CONTROL OF OUR WEATHER THROUGH THE DAYLIGHT HOURS...WITH UPSTREAM FRONTAL RAIN SLOW TO MOVE EAST DUE TO THE RIDGE ALONG THE EAST COAST. MAIN IMPACT TODAY WILL BE INCREASINGLY GUSTY EAST TO SOUTHEAST WINDS...ESPECIALLY ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS...AND ACROSS THE NORTHERN ADIRONDACKS INTO THE SAINT LAWRENCE VALLEY. SOUTHEAST WINDS OF 15-25 MPH WITH AFTERNOON GUSTS UP TO 35 MPH ARE LIKELY. EXPECT VARIABLE AMOUNTS OF CLOUD COVER THROUGH EARLY AFTERNOON...FOLLOWED BY INCREASING CLOUDS FROM SOUTHWEST TO NORTHEAST. BEST CHANCE FOR PROLONGED SUNSHINE WILL BE ACROSS CENTRAL/NRN VT. RAINFALL WILL HOLD OFF IN MOST AREAS...ALTHOUGH THERE IS A CHANCE FOR SHOWERS BY LATE IN THE DAY OVER THE SAINT LAWRENCE VALLEY AND WESTERN ADIRONDACKS. TEMPERATURES WILL BE A LITTLE MILDER THAN RECENT DAYS...BUT STILL A BIT COOL FOR LATE APRIL DUE MARINE MODIFIED AIR WORKING IN ON LOW LEVEL EASTERLY FLOW. MAX TEMPERATURES EXPECTED TO RANGE FROM 55 TO 60 DEGREES ACROSS MOST OF THE AREA THIS AFTERNOON. MARINE INFLUENCE A BIT MORE PRONOUNCED ACROSS S-CENTRAL VT...WITH TEMPS REMAINING IN THE UPR 40S TO AROUND 50 IN THE SPRINGFIELD VT AREA INTO THE SRN GREENS. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... AS OF 446 AM EDT TUESDAY...FOR TONIGHT THROUGH WEDNESDAY...700-500MB RIDGE AXIS REMAINS ACROSS CENTRAL/EASTERN NEW ENGLAND. BEST CHANCES FOR RAIN TONIGHT INTO WEDNESDAY MORNING MORNING WILL BE ACROSS NORTHERN NEW YORK...THEN AS RIDGE AXIS MOVES SLOWLY EAST...MORE WIDESPREAD RAINFALL MOVES INTO VERMONT WEDNESDAY AFTERNOON. MARINE MODIFIED AIR MASS REMAINS OVER THE REGION AND WE WILL SEE A CONTINUATION OF GUSTY SOUTHEAST WINDS AT 15 TO 25 MPH WITH GUSTS 35 MPH...ESPECIALLY DURING WEDNESDAY. MIN TEMPS TONIGHT IN THE MID 30S TO LOWER 40S...WITH HIGHS WEDNESDAY IN THE 40S TO AROUND 50. THE MOST WIDESPREAD AND SIGNIFICANT RAINFALL WITH THIS EVENT STILL SHAPING UP TO OCCUR WEDNESDAY NIGHT. FRONTAL RAIN BAND ASSOCIATED WITH APPROACHING OCCLUSION FROM THE SOUTHWEST WILL FINALLY SPREAD STEADY RAIN ACROSS THE ENTIRE FORECAST AREA. STRONG SOUTHERLY 850 MB JET MOVES ACROSS THE AREA WEDNESDAY NIGHT...WHEN BEST FORCING AND LIFT WILL OCCUR. THIS COUPLED WITH PRECIPITABLE WATER VALUES OF AROUND 1.25 INCHES ALL SUPPORT POSSIBILITY OF MODERATE TO EVEN HEAVY RAINFALL AT TIMES. GUSTY SOUTHEAST WINDS SHOULD GRADUALLY DIMINISH OVERNIGHT...BUT WILL STILL SEE SOME OROGRAPHIC INFLUENCES AFFECTING PRECIPITATION AMOUNTS...WITH SOME ENHANCEMENT ACROSS THE EAST FACING SLOPES OF THE GREEN MOUNTAINS AND THE NORTHERN ADIRONDACKS. RAIN WILL TAPER OFF TO SHOWERS DURING THURSDAY AS OCCLUDED FRONT MAKES ITS EASTWARD ACROSS FORECAST AREA...WHILE TRAILING MID LEVEL SHORTWAVE MOVES ACROSS THE AREA LATER IN THE DAY. HIGH POPS PREFERRED THROUGH MUCH OF THE DAY. TEMPS MILDER WITH HIGHS AROUND 60. A BIT COOLER IN EASTERN VERMONT WHERE FRONTAL PASSAGE NOT EXPECTED TILL LATE IN THE DAY. AS FOR STORM TOTAL RAINFALL...LOOKING AT 1.25-1.5" ACROSS SOUTH- CENTRAL VERMONT AND FOR THE NORTHERN ADIRONDACKS AND ST. LAWRENCE VALLEY. GENERALLY 0.75-1" IN THE CHAMPLAIN VALLEY AND NORTHEAST KINGDOM WHERE AMOUNTS LOWER DUE SOME SHADOWING. HYDROLOGICALLY...RIVERS HAVE RECEDED TO NEAR BASE LEVELS BUT WILL NEED TO MONITOR AUSABLE FORKS AND OTTER CREEK AT CENTER RUTLAND IF RAINFALL EXCEEDS CURRENT EXPECTATIONS. BASED ON CURRENT FORECAST...ALL RIVERS WILL REMAIN WITHIN BANKFULL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 351 AM EDT TUESDAY...VERY LITTLE CHANGE FROM PREVIOUS FORECAST THINKING AS THE REGION WILL LARGELY BE DOMINATED BY A SLOW MOVING CLOSED UPPER LEVEL LOW AND TROUGH THROUGH MUCH OF THE EXTENDED PERIOD. THE RESULT WILL BE GENERALLY CLOUDY AND COOL CONDITIONS WITH ON AND OFF CHANCES FOR PRECIPITATION...MAINLY DURING THE DAYLIGHT HOURS. TEMPS WILL RUN SLIGHTLY BELOW NORMAL WITH HIGHS IN THE 50S...AND LOWS IN THE MID 30S TO LOW 40S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THROUGH 18Z WEDNESDAY...LOW PRESSURE SYSTEM APPROACHES FROM THE GREAT LAKES REGION OVER THE NEXT FEW DAYS. CLOUDS AND PRECIPITATION ASSOCIATED WITH WARM FRONT SPREAD OUT AHEAD OF THE SYSTEM. VARIABLY CLOUDINESS ACROSS THE AREA TODAY...MAINLY VFR CEILING HEIGHTS...THOUGH OCCASIONALLY MVFR. WINDS ARE STRONG OUT OF THE SOUTHEAST. CLOUDS INCREASE AND LOWER OVERNIGHT AHEAD OF APPROACHING PRECIPITATION...WITH PRECIP MOVING INTO THE AREA TOWARDS MORNING. MAINLY VFR CONDITIONS CONTINUE THROUGH 12Z...THEN CONDITIONS LOWER TO MVFR. OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY... 18Z WED THRU 00Z THU...VFR WITH OCCASIONAL MVFR IN SHOWERS. 00Z THU THRU 00Z FRI...MVFR WITH OCCASIONAL IFR IN RAIN. 00Z FRI THRU SUN...MAINLY MVFR WITH OCCASIONAL VFR IN SCATTERED SHOWERS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...RJS NEAR TERM...BANACOS/RJS SHORT TERM...RJS LONG TERM...LAHIFF AVIATION...NEILES
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1251 PM EDT TUE APR 29 2014 .SYNOPSIS... HIGH PRESSURE WILL BRING DRY WEATHER THROUGH MOST OF TODAY. A LARGE AREA OF LOW PRESSURE ACROSS THE CENTRAL UNITED STATES WILL GRADUALLY SHIFT EASTWARD. THIS SYSTEM WILL BRING INCREASINGLY BREEZY CONDITIONS TODAY...FOLLOWED BY PERIODS OF RAIN...ESPECIALLY WEDNESDAY THROUGH THURSDAY MORNING. RAIN MAY BE HEAVY AT TIMES WEDNESDAY NIGHT. TEMPERATURES WILL REMAIN SLIGHTLY BELOW SEASONAL AVERAGES THROUGH THE END OF THE WEEK. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... AS OF 1247 PM EDT TUESDAY...DRIER AIR FROM THE EAST HAS PUSHED ACROSS MUCH OF CENTRAL AND NORTHERN VERMONT RESULTING IN MOSTLY SUNNY CONDITIONS THROUGH FILTERED HIGH CLOUDINESS. HAVE MADE SOME ADJUSTMENTS TO SKY COVER THROUGH THIS AFTERNOON BASED ON CURRENT CONDITIONS AND RUC RH PROFILES. MEANWHILE...FRONTAL RAINBAND IS APPROACHING SOUTHWESTERN ST. LAWRENCE COUNTY NY...WITH LIGHT RAIN DEVELOPING ACROSS FAR SWRN PORTIONS OF THE COUNTY LATE THIS AFTN. MINOR ADJUSTMENTS MADE TO POPS ACROSS ST. LAWRENCE COUNTY TO ACCOUNT FOR RADAR TRENDS AT THIS TIME...BUT OVERALL FORECAST IS ON TRACK. BROAD DEEP-LAYER LOW PRESSURE SYSTEM AFFECTING MUCH OF THE CENTRAL AND MIDWEST U.S. WILL GRADUALLY HAVE AN INCREASING INFLUENCE ON OUR WEATHER OVER THE COMING DAYS. MEANWHILE...IT LOOKS LIKE MOST OF THE FORECAST AREA WILL SEE ONE MORE DRY DAY TODAY BEFORE THE WET WEATHER ARRIVES. SURFACE RIDGE AXIS ACROSS NEW ENGLAND THIS MORNING WILL SHIFT SLOWLY EASTWARD INTO THE GULF OF MAINE BY THIS EVENING AND GENERALLY REMAIN IN CONTROL OF OUR WEATHER THROUGH THE DAYLIGHT HOURS...WITH UPSTREAM FRONTAL RAIN SLOW TO MOVE EAST DUE TO THE RIDGE ALONG THE EAST COAST. MAIN IMPACT TODAY WILL BE INCREASINGLY GUSTY EAST TO SOUTHEAST WINDS...ESPECIALLY ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS...AND ACROSS THE NORTHERN ADIRONDACKS INTO THE SAINT LAWRENCE VALLEY. SOUTHEAST WINDS OF 15-25 MPH WITH AFTERNOON GUSTS UP TO 35 MPH ARE LIKELY. EXPECT VARIABLE AMOUNTS OF CLOUD COVER THROUGH EARLY AFTERNOON...FOLLOWED BY INCREASING CLOUDS FROM SOUTHWEST TO NORTHEAST. BEST CHANCE FOR PROLONGED SUNSHINE WILL BE ACROSS CENTRAL/NRN VT. RAINFALL WILL HOLD OFF IN MOST AREAS...ALTHOUGH THERE IS A CHANCE FOR SHOWERS BY LATE IN THE DAY OVER THE SAINT LAWRENCE VALLEY AND WESTERN ADIRONDACKS. TEMPERATURES WILL BE A LITTLE MILDER THAN RECENT DAYS...BUT STILL A BIT COOL FOR LATE APRIL DUE MARINE MODIFIED AIR WORKING IN ON LOW LEVEL EASTERLY FLOW. MAX TEMPERATURES EXPECTED TO RANGE FROM 55 TO 60 DEGREES ACROSS MOST OF THE AREA THIS AFTERNOON. MARINE INFLUENCE A BIT MORE PRONOUNCED ACROSS S-CENTRAL VT...WITH TEMPS REMAINING IN THE UPR 40S TO AROUND 50 IN THE SPRINGFIELD VT AREA INTO THE SRN GREENS. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... AS OF 446 AM EDT TUESDAY...FOR TONIGHT THROUGH WEDNESDAY...700-500MB RIDGE AXIS REMAINS ACROSS CENTRAL/EASTERN NEW ENGLAND. BEST CHANCES FOR RAIN TONIGHT INTO WEDNESDAY MORNING MORNING WILL BE ACROSS NORTHERN NEW YORK...THEN AS RIDGE AXIS MOVES SLOWLY EAST...MORE WIDESPREAD RAINFALL MOVES INTO VERMONT WEDNESDAY AFTERNOON. MARINE MODIFIED AIR MASS REMAINS OVER THE REGION AND WE WILL SEE A CONTINUATION OF GUSTY SOUTHEAST WINDS AT 15 TO 25 MPH WITH GUSTS 35 MPH...ESPECIALLY DURING WEDNESDAY. MIN TEMPS TONIGHT IN THE MID 30S TO LOWER 40S...WITH HIGHS WEDNESDAY IN THE 40S TO AROUND 50. THE MOST WIDESPREAD AND SIGNIFICANT RAINFALL WITH THIS EVENT STILL SHAPING UP TO OCCUR WEDNESDAY NIGHT. FRONTAL RAIN BAND ASSOCIATED WITH APPROACHING OCCLUSION FROM THE SOUTHWEST WILL FINALLY SPREAD STEADY RAIN ACROSS THE ENTIRE FORECAST AREA. STRONG SOUTHERLY 850 MB JET MOVES ACROSS THE AREA WEDNESDAY NIGHT...WHEN BEST FORCING AND LIFT WILL OCCUR. THIS COUPLED WITH PRECIPITABLE WATER VALUES OF AROUND 1.25 INCHES ALL SUPPORT POSSIBILITY OF MODERATE TO EVEN HEAVY RAINFALL AT TIMES. GUSTY SOUTHEAST WINDS SHOULD GRADUALLY DIMINISH OVERNIGHT...BUT WILL STILL SEE SOME OROGRAPHIC INFLUENCES AFFECTING PRECIPITATION AMOUNTS...WITH SOME ENHANCEMENT ACROSS THE EAST FACING SLOPES OF THE GREEN MOUNTAINS AND THE NORTHERN ADIRONDACKS. RAIN WILL TAPER OFF TO SHOWERS DURING THURSDAY AS OCCLUDED FRONT MAKES ITS EASTWARD ACROSS FORECAST AREA...WHILE TRAILING MID LEVEL SHORTWAVE MOVES ACROSS THE AREA LATER IN THE DAY. HIGH POPS PREFERRED THROUGH MUCH OF THE DAY. TEMPS MILDER WITH HIGHS AROUND 60. A BIT COOLER IN EASTERN VERMONT WHERE FRONTAL PASSAGE NOT EXPECTED TILL LATE IN THE DAY. AS FOR STORM TOTAL RAINFALL...LOOKING AT 1.25-1.5" ACROSS SOUTH-CENTRAL VERMONT AND FOR THE NORTHERN ADIRONDACKS AND ST. LAWRENCE VALLEY. GENERALLY 0.75-1" IN THE CHAMPLAIN VALLEY AND NORTHEAST KINGDOM WHERE AMOUNTS LOWER DUE SOME SHADOWING. HYDROLOGICALLY...RIVERS HAVE RECEDED TO NEAR BASE LEVELS BUT WILL NEED TO MONITOR AUSABLE FORKS AND OTTER CREEK AT CENTER RUTLAND IF RAINFALL EXCEEDS CURRENT EXPECATATIONS. BASED ON CURRENT FORECAST...ALL RIVERS WILL REMAIN WITHIN BANKFULL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 351 AM EDT TUESDAY...VERY LITTLE CHANGE FROM PREVIOUS FORECAST THINKING AS THE REGION WILL LARGELY BE DOMINATED BY A SLOW MOVING CLOSED UPPER LEVEL LOW AND TROUGH THROUGH MUCH OF THE EXTENDED PERIOD. THE RESULT WILL BE GENERALLY CLOUDY AND COOL CONDITIONS WITH ON AND OFF CHANCES FOR PRECIPITATION...MAINLY DURING THE DAYLIGHT HOURS. TEMPS WILL RUN SLIGHTLY BELOW NORMAL WITH HIGHS IN THE 50S...AND LOWS IN THE MID 30S TO LOW 40S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THROUGH 12Z WEDNESDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD AS THE REGION REMAINS IN-BETWEEN UPPER LEVEL LOW PRESSURE SYSTEMS TO OUR EAST AND WEST TODAY. SOUTHEAST FLOW WILL BRING IN OCCASIONAL MVFR TO KRUT/KMPV EARLY THIS MORNING...BUT THE TREND WILL BE TOWARDS ALL SITES BEING VFR UNDER MID CLOUDS BY MID-DAY AS LOW LEVELS DRY OUT. SOUTHEAST FLOW STRENGTHENS THROUGH THE DAY AS WELL WITH ANY SUNSHINE INCREASING MIXING AND EXPECT TO SEE GUSTS OF 20-30KTS ACROSS THE REGION. LATE TODAY MID CLOUDS THICKEN IN ADVANCE OF PRECIP MOVING INTO NORTHERN NEW YORK THIS EVENING...THOUGH THOUGH CONDITIONS WILL REMAIN LARGELY VFR THROUGH 12Z EXCEPT FOR KRUT AND KMPV WHERE MVFR CIGS WILL RETURN OVERNIGHT. OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY... 12Z WED THRU 00Z THU...VFR WITH OCCASIONAL MVFR IN SHOWERS. 00Z THU THRU 00Z FRI...MVFR WITH OCCASIONAL IFR IN RAIN. 00Z FRI THRU 00Z SUN...MAINLY MVFR WITH OCCASIONAL VFR IN SCATTERED SHOWERS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...RJS NEAR TERM...BANACOS/RJS SHORT TERM...RJS LONG TERM...LAHIFF AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1257 PM CDT TUE APR 29 2014 .UPDATE... 18Z TAF DISCUSSION. && .AVIATION... MAIN FORECAST ISSUE REVOLVES AROUND CONVECTION IMPACTING AIRPORTS. LEANED HEAVILY ON THE HRRR MODEL FOR TIMING/IMPACTS...AND REMOVED TS MENTION FROM CKV TAF AS MOST ACTIVITY WILL BE FROM BNA EASTWARD. TSRA LOOKS TO AFFECT BNA/CSV BETWEEN 22/23Z THROUGH 02/03Z...WITH ADDITIONAL -SHRA EXPECTED AT CSV AFTER 02Z. MVFR/IFR CONDITIONS POSSIBLE IN HEAVIER -SHRA/-TSRA...BUT OTHERWISE VFR EXPECTED. PATCHY FOG POSSIBLE LATE IN THE TAF PERIOD. SHAMBURGER && .PREV DISCUSSION... /ISSUED 1247 PM CDT TUE APR 29 2014/ MESOSCALE UPDATE... SURFACE FRONT DRAPED FROM 998 MBAR CYCLONE CENTERED OVER FAR EASTERN IOWA DOWN THROUGH WESTERN KENTUCKY...WESTERN MIDDLE TENNESSEE THEN ON DOWN THROUGH CENTRAL MISSISSIPPI AND INTO A LOW THAT JUST FORMED IN CENTRAL LOUISIANA. DRIER AIR HAS MOVED IN OVER WESTERN MIDDLE TENNESSEE JUST WEST OF THE FRONT. SURFACE WINDS HAVE PICKED UP IN SPEED NORTHWEST MIDDLE TENNESSEE AND AREAS NORTHWARD TOWARD CYCLONE CENTER. THUNDERSTORMS HAVE DEVELOPED OVER NORTHEAST LOUISIANA AT MID-DAY. THESE STORMS WILL MOVE NORTHEAST INTO MISSISSPPI SHORTLY AND EVENTUALLY ACROSS NORTHERN ALABAMA AND INTO MIDDLE TENNESSEE AFTER 4 PM. A FEW STORMS COULD BE SEVERE SOUTH AND EAST OF NASHVILLE LATE AFTERNOON AND THIS EVENING WITH DAMAGING WINDS AND LARGE HAIL BEING THE MAIN THREAT. ISOLATED TORNADOES ARE POSSIBLE. && .OHX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR TNZ007>011- 025>034-056>066-075-077>080-093>095. && $$ 55
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1141 AM CDT TUE APR 29 2014 .UPDATE... VERY STRONG NORTH-NORTHWEST WINDS WERE SPREADING OUT OF THE PANHANDLE INTO OUR NORTH-CENTRAL AND NORTHEAST COUNTIES LATE THIS MORNING. BLOWING DUST ALREADY LESS THAN A MILE REPORTED IN SWISHER COUNTY...WITH SIMILAR REPORTS NORTHWARD THROUGH THE PANHANDLE. WE HAVE EXPANDED THE WIND ADVISORY TO INCLUDE CASTRO AND HALE COUNTIES...AND ALSO ADDED A BLOWING DUST ADVISORY FOR THOSE AREAS WITHIN THE WIND ADVISORY MAINLY ON THE CAP-ROCK. THE HIGHEST WIND SPEEDS STILL APPEAR TO BE IN THE 16Z-18Z TIME FRAME WITH THE LATEST RAP RUNS...THEN SHOULD SLOWLY SUBSIDE THROUGH THE AFTERNOON. ADDRESSING THE FREEZE WATCH FOR LATER TONIGHT...FIRST THOUGHTS ARE THIS IS A GENUINELY COLD AIRMASS BUT WIND SPEEDS MAY NOT DROP ENOUGH FOR A WIDESPREAD HARD FREEZE. WILL STUDY MORE THIS AFTERNOON. RMCQUEEN && .AVIATION... WINDS AND BLOWING DUST RESTRICTIONS AT BOTH SITES THIS AFTERNOON EXPECTED TO TAPER OFF TONIGHT WITH VFR THUS DOMINATING. A HIGH- BASED LOW CLOUD DECK WILL AT LEAST SCATTER ACROSS BOTH KLBB AND KCDS THIS AFTERNOON. RMCQUEEN && .FIRE WEATHER... STRONG DRY WINDS TODAY...WITH AFTERNOON HUMIDITY BOTTOMING OUT AROUND 15 TO 25 PERCENT TODAY...EVEN LESS THAN 15 PERCENT ACROSS THE SOUTHWESTERN SOUTH PLAINS WHERE RED FLAG MINUTES LIKELY WILL CLICK OFF. BUT WITH TEMPERATURES 10 TO 15 DEGREES COLDER THAN NORMAL WE WILL NOT ISSUE EITHER A RED FLAG OR FIRE DANGER PRODUCT FOR TODAY. THIS IS A BIT OF A GREY AREA FOR US AS THE WINDS APPEAR STRONG ENOUGH TO BE A SIGNIFICANT CONCERN...BUT WILL BE AT LEAST SOMEWHAT COUNTERED BY THE SIGNIFICANTLY BELOW NORMAL TEMPERATURES. CAUTION CERTAINLY IS ADVISED FOR ANYONE CONTEMPLATING BURNS TODAY. RMCQUEEN && .PREV DISCUSSION... /ISSUED 616 AM CDT TUE APR 29 2014/ AVIATION... ANOTHER LOW TO MID LEVEL SPEED MAX IS ROTATING SWD THROUGH THE CNTL PLAINS THIS MORNING AND WILL MOVE OVER THE FCST AREA BY MID MORNING WITH NORTH TO NW WINDS INCREASING TO AROUND 25G35KT FOR LATE MORNING TO EARLY EVENING. SOME MINOR OBSTRUCTION TO VSBY DUE TO BLDU EXPECTED AT KLBB. PREV DISCUSSION... /ISSUED 230 AM CDT TUE APR 29 2014/ SHORT TERM... TODAY WILL BE ANOTHER...BUT WHAT SHOULD BE THE LAST...WINDY DAY ACROSS THE FCST AREA...ALTHOUGH SOME NORTH BREEZES ARE STILL EXPECTED LATER IN THE WEEK. THE STORM SYSTEM THAT HAS BEEN RESPONSIBLE FOR THE WIND THE LAST COUPLE OF DAYS IS NOW CENTERED OVER IOWA AND MISSOURI AND WILL SHIFT EWD TO ILLINOIS AND WISCONSIN BY OVERNIGHT TONIGHT. SFC LOW PRESSURE CENTER WILL BE NEARLY CO-LOCATED WITH THE UPPER SYSTEM. HOWEVER...HIGH PRESSURE BUILDING IN BEHIND A COLD FRONT THAT MOVED THROUGH THE AREA LAST NIGHT WILL KEEP THE SFC PRESSURE GRADIENT FAIRLY TIGHT. IN ADDITION...MODELS CONTINUE TO SHOW A CORE OF HIGHER NORTH TO NW WINDS AT 850-700 MB THAT WILL ROTATE SWD ON THE BACK SIDE OF THE MASSIVELY LARGE UPPER STORM SYSTEM. MIXING OF THAT MOMENTUM TO THE SFC SHOULD RESULT IN AT LEAST 20-30 MPH WINDS AREAWIDE WITH A VERY GOOD CHANCE OF THE NERN THIRD OF THE FCST AREA SEEING WINDS PUSH TOWARD 35 MPH... PARTICULARLY THIS MORNING BEFORE PRESSURE GRADIENT BEGINS TO RELAX. SOME CONCERN THAT MIXING MAY NOT BE TERRIBLY EFFICIENT WITH THE COLD ADVECTION AND THAT LINGERING MID LEVEL CLOUD COVER MAY ALSO RETARD MIXING POTENTIAL. MODELS SEEM TO BE PICKING UP ON SOME OF THESE CONCERNS AS WELL. HOWEVER...ATTM WILL GIVE THE NOD TOWARD THE STRONGER GFS GIVEN SLIGHTLY BETTER INITIALIZATION AND EXPECTATION THAT THE WRF-NAM IS OVERDOING MID LEVEL MOISTURE THAT WILL REMAIN OVER THE REGION. AS A RESULT WILL ISSUE A WIND ADVISORY FOR TODAY FOR AREAS GENERALLY EAST OF A TULIA TO SPUR LINE. OTHER CONCERN THIS MORNING IS POTENTIAL FOR A LIGHT FREEZE ACROSS THE NWRN ZONES LATE TONIGHT AND EARLY WEDNESDAY. UNSEASONABLY COLD AIR MASS WILL CONTINUE TO SETTLE ACROSS THE FCST AREA THROUGH THE EVENING HOURS. HAVE SOME CONCERN BASED ON UNCERTAINTIES REGARDING MID LEVEL CLOUD COVER AND HOW WELL SFC WINDS WILL BE ABLE TO DIMINISH WITH ANOTHER 850 MB CORE OF STRONGER WINDS PROGGED TO MOVE OVERHEAD...BUT BOTH RAW MODEL TEMPS AND MOS TEMPS SUGGEST THAT A PERIOD OF 30-32F IS POSSIBLE IN AT LEAST POCKETS OF THE NWRN ZONES. AM NOT SOLD ON THE IDEA...BUT GIVEN WE ARE NOW ABOUT 8-12 DAYS AFTER THE AVG DATE OF THE LAST FREEZE AND A LITTLE MORE SINCE THE ACTUAL LAST FREEZE FOR THAT AREA AM INCLINED TO ISSUE A FREEZE WATCH. LONG TERM... THE UA LOW THAT HAS BEEN DOMINATING THE CENTRAL CONUS...HAS SLOWLY SHIFTED NE TOWARDS THE WRN GREAT LAKES REGION EARLY THIS MORNING...WHILST UA RIDGING IMPINGES ON THE WRN CONUS. AS SUCH...WNWRLY FLOW ALOFT DOMINATED ACROSS THE SOUTHERN PLAINS...LEADING TO PERSISTENT SFC RIDGING AND THUS PERSISTENT NRLY SFC WINDS USHERING IN A COOLER AIRMASS. THIS WILL RESULT IN BELOW NORM TEMPS /50S AND 60S/ THROUGH AT LEAST THURSDAY...WITH THE COOLEST DAY OF THE WEEK OCCURRING TOMORROW. MID-UPPER HEIGHT GRADIENTS WILL BE WANING BY TOMORROW...BUT SLIGHTLY BREEZY NRLY WINDS /15-20 MPH/ ARE STILL ON TAP /MORE SO OFF THE CAPROCK/...WITH MOST WELCOMED LIGHT WIND SPEEDS OCCURRING BY THURSDAY. AN UA SHORTWAVE TROUGH WILL BE SWEEPING ACROSS THE REGION ON THURSDAY...WITH MODELS CONTINUING TO DEPICT LIGHT QPF SIGNALS ACROSS EAST NM. BOTH THE NAM AND GFS CONFINES THE PRECIP TO THE MOUNTAINOUS TERRAIN OF NM...WITH THE ECMWF DEPICTING A STRONGER SHORTWAVE TROUGH AND HENCE THE POTENTIAL FOR LIGHT PRECIP ACROSS WRN ZONES. MODEL SOUNDINGS DISPLAYING A RATHER DRY SUB-CLOUD LAYER SUGGEST MID-LEVEL CLOUDINESS LIKELY BEING THE RULE...AND WILL OPT TO CONTINUE BELOW MENTIONABLE POPS ATTM. UA RIDGING WILL PROGRESS EWRD ACROSS THE CENTRAL CONUS THIS WEEKEND WHICH WILL BRING ABOUT NEAR ZONAL FLOW AND CAUSE THE STUBBORN BROAD UA LOW TO FINALLY LIFT NE INTO QUEBEC. GRADUALLY WARMING WILL THEREBY COMMENCE AS THE RETURN OF SFC LEE TROUGHING AND S-SW SFC WINDS TAKES SHAPE. TEMPS WILL WARM FROM THE 70S AND 80S ON FRIDAY TO THE 80S AND 90S BY SUNDAY. ABOVE NORMAL WARMTH WILL PERSIST INTO EARLY NEXT WEEK...THOUGH TEMPS WILL BE A FEW DEGREES COOLER NEAR THE TEXAS AND NEW MEXICO BORDER...DUE TO HEIGHT FALLS FROM A PACIFIC UA DISTURBANCE MOVING ON THE CALI SHORE. ALL IN ALL...A RELATIVELY QUIET AND DRY EXTENDED FORECAST. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 62 32 59 35 61 / 0 0 0 10 10 TULIA 64 34 60 37 64 / 0 0 0 0 10 PLAINVIEW 65 35 61 37 64 / 0 0 0 0 10 LEVELLAND 67 36 63 36 64 / 0 0 0 0 10 LUBBOCK 67 37 63 36 65 / 0 0 0 0 10 DENVER CITY 67 39 64 38 64 / 0 0 0 0 10 BROWNFIELD 68 39 64 37 66 / 0 0 0 0 10 CHILDRESS 70 41 67 38 69 / 0 0 0 0 0 SPUR 71 41 66 38 69 / 0 0 0 0 10 ASPERMONT 73 44 67 38 71 / 0 0 0 0 10 && .LUB WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ022>026-029>032-037-038. BLOWING DUST ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ022>025-029>031. FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR THE FOLLOWING ZONES: TXZ021-022-027-028. && $$ 05/99/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
250 PM CDT TUE APR 29 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 250 PM CDT TUE APR 29 2014 CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED STRONG RIDGING ALONG THE U.S. WEST COAST THROUGH SOUTHWEST CANADA...INTO HUDSON BAY AND NEW ENGLAND...WHILE AN UPPER LOW WAS CUT OFF OVER THE FORECAST AREA. A DRY SLOT ROTATING AROUND THE UPPER LOW HAS KICKED THE SHOWERS ALONG AND NORTH OF I-90 THIS MORNING TO LAKE SUPERIOR AND BACK SOUTHWEST INTO SOUTHWEST MN. MEANWHILE... UNDER THE UPPER LOW...SHOWERS HAVE DEVELOPED OVER EASTERN IOWA INTO SOUTHERN WI. UPWARDS OF 250 J/KG OF MOST UNSTABLE CAPE WAS DEPICTED BY RAP ANALYSIS SUPPORTING THE SHOWERS. THIS PRECIPITATION WAS ALSO CO-LOCATED WITH A SURFACE LOW NEW GRANT COUNTY WITH A WARM FRONT EXTENDING EAST TO KENOSHA WI AND A COLD FRONT EXTENDING SOUTHWESTWARD. COLDER AIR CONTINUES TO GET GRADUALLY WRAPPED AROUND THE UPPER LOW TOO...WITH THE 12Z MPX AND INL SOUNDINGS REPORTING 925MB AND 850MB TEMPS BETWEEN 0 AND -2C. THIS COLDER AIR ALLOWED FOR SOME LIGHT SNOW TO FALL NORTH OF THE TWIN CITIES THIS MORNING. EVEN SOME SNOW FELL ALONG AND NORTH OF I-90 THIS MORNING WHERE HEAVIER PRECIPITATION RESULTED IN DYNAMIC AND EVAPORATIVE COOLING. MOST OF THE SNOW WAS CONFINED TO GRASSY SURFACES. VERY LITTLE CHANGE IS FORECAST IN THE UPPER LEVEL PATTERN TONIGHT AND WEDNESDAY AS THE UPPER LOW BASICALLY MOVES NOWHERE. THIS LEAVES SHORTWAVES ROTATING AROUND THE UPPER LOW TO IMPACT THE MOVEMENT OF PRECIPITATION. FOR TONIGHT...MAIN COLD CONVEYOR BELT AFFECTING MINNESOTA CURRENTLY LOOKS TO WRAP BACK INTO MUCH OF SOUTHEAST MN AND NORTHEAST IOWA THIS EVENING...THEN LINGER THROUGH THE OVERNIGHT HOURS WHILE POSSIBLY BREAKING UP SOME. SOME OF THE COLD CONVEYOR BELT COULD WRAP INTO SOUTHWEST AND CENTRAL WISCONSIN OVERNIGHT. COMBINATION OF NOCTURNAL COOLING AND EVAPORATIVE COOLING FROM SOME LOW LEVEL DRY AIR WRAPPING AROUND THE SURFACE LOW MAY ALLOW THE RAIN TO CHANGE OVER TO SNOW...AS DEPICTED IN WET-BULB ZERO HEIGHT PROGS DROPPING BELOW 1000 FT. AUSTIN TO CHARLES CITY LOOKS TO HAVE THE HIGHEST PROBABILITY OF SEEING SNOW ACCUMULATION. HOWEVER...LITTLE ACCUMULATION IS ANTICIPATED SINCE THE PRECIPITATION IS EXPECTED TO BE LIGHT AND THE GROUND IS WARM. TO THE EAST...THE SHOWERS ACROSS SOUTHERN WISCONSIN SHOULD ROTATE INTO CENTRAL AND NORTHWEST WISCONSIN THROUGH THE NIGHT. A SLIGHTLY COOLER NIGHT IS LIKELY...PARTICULARLY WEST OF THE MISSISSIPPI RIVER DUE TO THE COOLER AIR OVER MINNESOTA ROTATING AROUND THE UPPER LOW. ON WEDNESDAY...THERE IS NO REAL STRONG IDENTIFICATION FEATURE FOR PRODUCING PRECIPITATION...THOUGH MOST MODELS CONTINUE TO INDICATE LIGHT SHOWER ACTIVITY AROUND. IT APPEARS MUCH OF THIS SHOWER ACTIVITY IS LIKELY A INSTABILITY ISSUE...RESULTING FROM COLDER AIR ALOFT FROM THE UPPER LOW. SCATTERED TO NUMEROUS SHOWERS SEEMS THE BEST WAY TO DESCRIBE THE PRECIPITATION. 850MB TEMPS RANGING FROM -3C WEST TO 2C EAST...PLENTY OF CLOUD COVER AND THE SHOWER ACTIVITY WILL HELP TO KEEP TEMPERATURES DOWN WELL BELOW NORMAL AGAIN. SIDED TOWARDS THE LOW SIDE OF TEMPERATURE GUIDANCE. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 250 PM CDT TUE APR 29 2014 FOR THOSE LOOKING FOR A PATTERN CHANGE...ITS COMING...WITH GOOD MODEL AGREEMENT FOR A SWITCH TO UPPER LEVEL RIDGING OVER THE FORECAST AREA EARLY NEXT WEEK. SO THERE WILL BE A GRADUAL MODERATION TO TEMPERATURES. THE UPPER LOW LOOKS TO HANG AROUND THE FORECAST AREA WEDNESDAY NIGHT...BUT THEN A MORE POTENT SHORTWAVE DROPPING DOWN THROUGH SOUTH CENTRAL CANADA WILL HELP TO KICK THE UPPER LOW OUT TO THE NORTHEAST ON THURSDAY. BY 00Z FRIDAY...MODELS HAVE THE UPPER LOW CENTERED OVER LAKE HURON. UNTIL THE UPPER LOW DEPARTS...WE WILL NEED TO CONTEND WITH SHOWER ACTIVITY ROTATING AROUND IT...ESPECIALLY THROUGH THURSDAY MORNING. THERE ARE SOME INDICATIONS THAT THE SHOWER ACTIVITY COULD DIMINISH WEST OF THE MISSISSIPPI RIVER THURSDAY AFTERNOON FROM THE 29.00Z ECMWF AND 29.12Z CANADIAN...BUT THIS WILL ALL HINGE ON HOW FAST THE UPPER LOW EJECTS. TEMPERATURES ARE STILL GOING TO BE COOL THROUGH THURSDAY GIVEN 850MB TEMPS HOLDING BETWEEN - 2C AND 1C AND CLOUDS/SHOWERS. DESPITE THE COOL 850MB TEMPS...PROGGED WETBULB ZERO HEIGHTS ARE ABOVE 1500 FT AGL...WHICH SHOULD KEEP SNOW OUT OF THE PICTURE. THE PLAGUE OF RAIN THAT HAS BEEN OVER THE AREA MAY FINALLY TAKE A BREAK THURSDAY NIGHT AS SOME WEAK RIDGING BOTH AT THE SURFACE AND ALOFT MOVES INTO THE AREA. CLOUD CLEARING LOOKS TO BE A BIT SLOWER...AND POSSIBLY NOT EVEN CLEARING AT ALL IN WISCONSIN. IN FACT...THE 29.12Z NAM SUGGESTS PERHAPS SOME DRIZZLE LINGERING IN WISCONSIN AS A RESULT OF THESE CLOUDS HANGING AROUND. ALTHOUGH ITS IN THE MINORITY OF MODEL GUIDANCE...FELT A 20 PERCENT CHANCE FOR RAIN IS WARRANTED FOR WISCONSIN. A WEAK SHORTWAVE IS PROGGED TO DROP SOUTHEAST THROUGH THE AREA ON FRIDAY...IN THE NORTHWEST FLOW ALOFT BEHIND THE EJECTING UPPER LOW. 29.12Z GFS IS MOST AGGRESSIVE WITH PRODUCING SHOWERS WITH THIS WAVE...BUT THE ECMWF HINTS AT POTENTIAL PRECIPITATION. KEPT SOME LOWER PROBABILITIES IN FOR THIS WAVE TO ACCOUNT FOR THESE MODEL SCENARIOS. FOR THE WEEKEND...THE MAIN ITEM OF INTEREST IS THE AFOREMENTIONED POTENT SHORTWAVE OVER SOUTH CENTRAL CANADA PROGGED TO BARREL THROUGH NORTHERN PORTIONS OF THE UPPER GREAT LAKES SATURDAY AFTERNOON AND EVENING. THERE ARE SOME MODEL DIFFERENCES ON SPEED AND LOCATION...BUT ALL HAVE THE SAME IDEA. GIVEN THE POTENT NATURE OF THE WAVE...PRECIPITATION LOOKS LIKELY...BUT THE DIFFERENCES CREATE ISSUES WITH GOING TOO HIGH ON CHANCES. FEEL PRETTY CONFIDENT NORTHERN WISCONSIN WILL SEE RAIN...BUT ELSEWHERE IT IS A BIT UNCERTAIN. CANNOT RULE OUT SOME THUNDER EITHER WITH THE SHORTWAVE GIVEN SOME STEEPER MID LEVEL LAPSE RATES PROGGED TO ACCOMPANY IT. LOOKS LIKE BOTH SATURDAY NIGHT AND SUNDAY WILL THEN END UP DRY DUE TO SUBSIDENCE BEHIND THE WAVE. WITH THE RETURN TO UPPER RIDGING EARLY NEXT WEEK...ISENTROPIC LIFT AND WARM ADVECTION COME INTO THE PICTURE. BOTH THE 29.12Z ECMWF AND GFS DEPICT SOME LIGHT PRECIPITATION POSSIBLE FOR BOTH MONDAY AND TUESDAY...ENOUGH TO WARRANT 20-30 PERCENT CHANCES. THE WARM ADVECTION CLOUDS/PRECIPITATION AND A WARM FRONT SITUATED TO THE SOUTH CLOSER TO I-70 WILL HOLD TEMPERATURES BACK FROM REACHING NORMAL. NEVERTHELESS...THE TEMPERATURES EARLY NEXT WEEK LOOK TO BE MUCH CLOSER TO NORMAL COMPARED TO NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 104 PM CDT TUE APR 29 2014 UPPER LOW WILL BE NEARLY STATIONARY OVERHEAD THROUGH THE NEXT 24 HOURS...LEADING TO IFR/LIFR MAINLY CLOUD CEILING CONDITIONS. KRST WILL SEE A LIGHT RAIN/SNOW MIXTURE...SWITCHING TO MAINLY RAIN LATER THIS AFTERNOON AND THEN BACK TO A MIX THIS EVENING AGAIN WITH COOLING. KLSE EXPECTED TO SEE OFF/ON SCATTERED -SHRA ACTIVITY THROUGH THE PERIOD. && .HYDROLOGY... ISSUED AT 250 PM CDT TUE APR 29 2014 THE MAJORITY OF THE HEAVY RAIN HAS ENDED NOW FOR THE REST OF THE WEEK...WHICH WILL GREATLY HELP DIMINISH THE CONCERN FOR FLOODING ON TRIBUTARIES. RUNOFF IS EXPECTED TO RAISE WATER LEVELS ON THE TRIBUTARIES BUT NO FLOODING IS ANTICIPATED FOR THEM. MEANWHILE...PLENTIFUL RAIN THAT FELL UPSTREAM OVER CENTRAL MINNESOTA COMBINED WITH THE RAIN THAT FELL OVER THE FORECAST AREA WILL ALLOW THE MISSISSIPPI RIVER TO CONTINUE TO RISE. MANY SITES ALONG THE MISSISSIPPI RIVER SHOULD RISE TO OR ABOVE FLOOD STAGE OVER THE NEXT WEEK. FLOOD WATCHES AND WARNINGS ARE POSTED ALONG THE MISSISSIPPI AS A RESULT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR WIZ033-041-053-054-061. MN...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR MNZ088-096. IA...FLOOD WATCH FROM LATE SATURDAY NIGHT THROUGH TUESDAY EVENING FOR IAZ011-030. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...DAS HYDROLOGY...AJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND WEDNESDAY ISSUED AT 220 PM CDT TUE APR 29 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A LARGE OCCLUDED CYCLONE SPINNING OVER EASTERN IOWA AND AN OCCLUDED FRONT EXTENDING EAST ACROSS LOWER MICHIGAN. EARLIER BAND OF RAIN AND SNOW THAT IMPACTED THE REGION THIS MORNING HAS PIVOTED AROUND TO THE UPPER PENINSULA AND NORTHWEST WISCONSIN FOR THE MOST PART. STILL SOME LIGHT RAIN AND LIGHT SNOW ONGOING OVER NORTH-CENTRAL WISCONSIN WHERE EARLIER REPORTS INDICATE 1 TO 2 INCHES OF SNOW FELL. THOUGH OBS ARE NOT NECESSARILY REPORTING IT...THINK A WIDESPREAD AREA OF MIST AND DRIZZLE ARE OCCURRING ELSEWHERE. NEXT AREA OF SHOWERS IS DEVELOPING OVER SOUTHERN WISCONSIN AND NORTHERN ILLINOIS AND ARE BEGINNING TO ENTER THE SOUTHERN FORECAST AREA. STILL ANOTHER AREA OF SHOWERS IS ROTATING AROUND THE UPPER LOW OVER NORTHERN MISSOURI. TIMING OF SHOWERS IS THE MAIN FORECAST CONCERN. TONIGHT...THE LARGE AND STUBBORN OCCLUDED CYCLONE WILL LIFT NORTHEAST INTO SOUTHWEST WISCONSIN LATE TONIGHT. AHEAD OF THE LOW...THE OCCLUDED FRONT WILL SHIFT NORTHWARD INTO CENTRAL WISCONSIN. NEXT AREA OF RAINFALL IS TAKING SHAPE OVER SOUTHERN WISCONSIN AND NORTHERN ILLINOIS AND SHOULD MOVE INTO CENTRAL AND NORTHEAST WISCONSIN LATER THIS AFTERNOON INTO THIS EVENING. ANOTHER SHORTWAVE WILL BE ROTATING AROUND THE UPPER LOW FROM NORTHERN MISSOURI AND MOVE INTO NORTHEAST WISCONSIN LATE TONIGHT...WHICH SHOULD BRING ADDITIONAL RAINFALL. A SILVER LINING IS THAT TEMPERATURES WILL BE WARMING ALOFT...ENOUGH TO PRECLUDE A MENTION OF SNOW. BUT WITH THE SURFACE LOW MOVING INTO THE STATE AND WIND FIELDS WEAKENING...LOW STRATUS SHOULD BE GRADUALLY LOWERING THROUGH THE NIGHT AND COULD SEE AREAS OF FOG DEVELOP OVER CENTRAL AND EAST-CENTRAL WISCONSIN. LOWS IN THE MID 30S TO LOWER 40S. WEDNESDAY...THE UPPER LOW WILL MEANDER NORTHEAST ACROSS THE FORECAST AREA. THE SHORTWAVE ARRIVING LATE TONIGHT COULD BRING DECENT RAINS INTO NORTHEAST WISCONSIN DURING THE MORNING BEFORE SHIFTING NORTH INTO THE UPPER PENINSULA IN THE AFTERNOON. BUT THE PRESENCE OF THE LOW SHOULD STILL GENERATE SCATTERED SHOWERS FOR THE AFTERNOON. SOME MODERATION OF TEMPS COULD BRING HIGHS INTO THE MID 40S NORTH TO THE LOW 50S SOUTH. .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY ISSUED AT 220 PM CDT TUE APR 29 2014 PCPN TRENDS AND TEMPERATURES ARE THE MAIN FCST CONCERNS. THE UPPER LEVEL LEVEL LOW IS EXPECTED TO DRIFT EAST ACROSS WI ON WEDS NGT. SEVERAL MODELS SUGGEST THAT A WEAK DRY SLOT WILL BE IN PLACE OVER EASTERN WI DURING THE EVENING...THEN GRADUALLY FILL IN AS THE LOW SHIFTS EAST. WILL ADJUSTED POP TRENDS ACCORDINGLY...BUT 12 HOUR POPS WILL BE IN THE LIKELY CATEGORY OVER THE ENTIRE CWA. WILL CONTINUE WITH LIKELY POPS ON THURSDAY AS THE UPPER LOW WEAKENS OVER NE WI. PCPN WILL BECOME MORE SCATTERED ON THU NGT/FRI... AS A COUPLE S/W TROFS AND A WEAK COLD FRONT TRAVERSE THE REGION. GFS/ECMWF HAVE COME INTO BETTER AGREEMENT ON A DYNAMIC SYSTEM AND COLD FRONT MOVG THROUGH WI ON SATURDAY. THE LFQ OF A 110 KT JET STREAK AND A POTENT S/W TROF WILL MOVE THROUGH DURING THE MIDDLE OF THE DAY. HAVE INCREASED POPS TO 50-60 PERCENT...AND ADDED ISOLD THUNDER AS H7-H5 LAPSE RATES INCREASE TO 7 C/KM. AFTER THE COLD FRONT MOVES THROUGH...CANADIAN HIGH PRESSURE WILL BUILD INTO THE WESTERN GREAT LAKES...AND SHOULD BRING A RARE PERIOD OF DRY WEATHER FROM SATURDAY NIGHT THROUGH SUNDAY NIGHT. AS THE CANADIAN HIGH SHIFTS EAST EARLY IN THE NEXT WORK WEEK... SFC/H8 WARM FRONTS WILL WORK THEIR WAY TOWARD THE WI/IL BORDER. THIS MAY BRING A SMALL OF SHOWERS...AND POSSIBLY ISOLD TSTMS OVER OUR SOUTHERN COUNTIES. DUE TO LOW CONFIDENCE HAVE KEPT THE MENTION OF THUNDER OUT OF THE FCST. TEMPERATURES WILL REMAIN BLO NORMAL FOR MOST OF THE PERIOD. WAA EARLY NEXT WEEK SHOULD ALLOW TEMPERATURES TO MODERATE A LITTLE BIT. IF THE RAIN HOLDS OFF AND PARTIAL SUNSHINE OCCURS... TEMPS MAY NEED TO BE RAISED ON MONDAY AND TUESDAY. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1145 AM CDT TUE APR 29 2014 A LARGE UPPER LEVEL LOW WILL GRADUALLY MOVE NORTHEAST INTO THE WESTERN GREAT LAKES LATE TONIGHT INTO WEDNESDAY. THIS LOW WILL CONTINUE TO SEND BANDS OF PRECIPITATION ACROSS NORTH-CENTRAL AND NORTHEAST WISCONSIN THROUGH THE END OF THE TAF PERIOD. THE SNOWFALL ACROSS NORTH-CENTRAL WISCONSIN IS ANTICIPATED TO SWITCH BACK TO RAIN EARLY TO MIDDLE AFTERNOON...WHICH WILL HELP VSBYS IMPROVE TO MVFR. HOWEVER...PLENTY OF IFR CIGS ARE LIFTING NORTHWARD ACROSS CENTRAL AND NORTHEAST WISCONSIN AND EXPECT CIGS TO REMAIN IFR THROUGH EARLY THIS EVENING. THEN AS A BROAD SURFACE LOW MOVES INTO THE SOUTHWEST WISCONSIN LATE TONIGHT...WEAKENING WINDS AND AN INFLUX OF MOISTURE WILL LIKELY LOWER CIGS INTO THE LIFR RANGE. DENSE FOG IS ALSO POSSIBLE ALONG THE LAKE MICHIGAN SHORELINE AS THIS OCCURS AS WELL. EXPECT ONLY SLOW IMPROVEMENT OF THE CIGS/VSBSY TOMORROW MORNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1146 AM CDT TUE APR 29 2014 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY ISSUED AT 346 AM CDT TUE APR 29 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW UPPER LOW AND ASSOCIATED SURFACE SYSTEM OVER FAR SOUTHWEST IA. THIS SYSTEM IS EXPECTED TO MOVE SLOWLY NORTHEAST INTO WI THROUGH THIS PERIOD. EXPECT PERIODS OF RAIN TO MOVE NORTH THROUGH THE STATE THROUGH WED AS ENERGY ROTATES AROUND LOW. HEAVIER AREA OF RAIN NOW MOVING MOVING THROUGH SOUTHERN HALF OF STATE. DRY AIR VERY PRESENT ON APX EVENING SOUNDING BEING ADVECTED IN OVER NORTHERN WI ON STRONG EAST WINDS...LIMITING PCPN AMOUNTS SO FAR. THIS DRY AIR VERY EVIDENT OVER FAR NORTH WHERE DEW POINTS STILL IN THE 20S. AS PCPN MOVES IN OVER NORTH SEEING SNOW/SLEET SHOWING UP...THOUGH SURFACE TEMPS STILL MILD SO AM NOT LOOKING AT ANY ACCUMULATION. WILL CONTINUE TO CARRY MIX INTO THE MORNING HOURS. LOW LEVEL TEMP FIELDS POINT TO MAINLY RAIN THROUGH REMAINDER OF THE PERIOD AS WEAK WAA BRINGS 850 TEMP UP TO +2 OVER VILAS COUNTY BY TONIGHT. AS LOW MOVES NORTH LOOK FOR WINDS TO BACK OFF...BECOMING LIGHT LATER TONIGHT INTO WED. MAY SEE SOME FOG WITH LINGERING MOISTURE. WILL ADD TO MARINE ZONES AT THIS TIME AND LET LATER SHIFT DEBATE LAND ZONES. BEST MOISTURE/PW`S OVER 1 INCH NOW OFF TO THE EAST OF STATE...WILL DROP ISSUING ESF WITH LESSER QPF EXPECTED. TEMPS TO REMAIN BELOW SEASONABLE NORMS. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY ISSUED AT 346 AM CDT TUE APR 29 2014 UNSETTLED CONDITIONS WILL CONTINUE INTO THE WEEKEND AND POSSIBLY EARLY NEXT WEEK. FIRST...UPPER LOW WILL SLOWLY MOVE AWAY FROM THE AREA ON THURSDAY...THEN SEVERAL SYSTEMS MOVING THROUGH THE MEAN FLOW WILL BRING CHANCES FOR SHOWERS AT TIMES FRIDAY INTO EARLY NEXT WEEK. UPPER LOW EXPECTED TO SLOWLY MOVE ACROSS THE AREA WEDNESDAY NIGHT. WILL NEED TO WATCH FOR A POTENTIAL SHARS (SUBTLE HEAVY RAINFALL SIGNATURE EVENT) WITH THESE TYPES OF SYSTEMS DEPENDING ON LOCATION OF SHORTWAVE ENERGY AND LOW LEVEL CONVERGENCE AREAS. THESE TYPES OF SYSTEM COULD BRING CONSIDERABLY MORE RAIN THAT WHAT IS IN THE QPF FORECAST GRID. UNFORTUNATELY...WAY TOO EARLY TO DETERMINE IF OR WHERE THIS TYPE OF EVENT WOULD FORM. EVEN IF A SHARS EVENT DOES DEVELOP...IT WOULD BRING LOCALIZED HEAVIER RAINFALL TOTALS THAN WHAT IS IN THE CURRENT FORECAST AND COULD IMPACT RIVER FORECASTS. COOL CYCLONIC FLOW WILL CONTINUE TO BRING INSTABILITY SHOWERS ON THURSDAY WHICH MAY LINGER INTO THURSDAY EVENING...WITH POSSIBILITY OF AN ISOLATED SHOWER BETWEEN 06Z-12Z FRIDAY. ON FRIDAY...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED COLD FRONT WILL MOVE ACROSS THE REGION ON FRIDAY (MAYBE FRIDAY EVENING ACROSS THE EAST). COOL CYCLONIC FLOW...FORCING ALOFT AND FRONTAL BOUNDARY WITH DEW POINTS POOLING INTO THE LOWER TO MIDDLE 40S WILL BE SUFFICIENT FOR A CHANCE OF SHOWERS. LOOKED AT THUNDER PROSPECTS...DID NOT SUPPORT ADDING THUNDER AT THIS POINT. A STRONGER SHORTWAVE IS EXPECTED MOVE ACROSS THE WESTERN GREAT LAKES ON SATURDAY...BRINGING ANOTHER CHANCE OF SHOWERS. A WEAK BOUNDARY IS EXPECTED TO DROP ACROSS THE AREA DURING THE PEAK HEATING OF THE DAY ON SUNDAY...WARRANTING A CHANCE OF SHOWERS. A FEW SHOWERS MAY LINGER INTO SUNDAY EVENING...THEN DRY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF SUNDAY NIGHT INTO MONDAY MORNING. WITH THE EXPECTED CLOUDS AND SOME RAIN DURING THE DAY TIME HOURS...EXPECTED TEMPERATURES TO RUN BELOW NORMAL FOR MUCH OF THE PERIOD. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1145 AM CDT TUE APR 29 2014 A LARGE UPPER LEVEL LOW WILL GRADUALLY MOVE NORTHEAST INTO THE WESTERN GREAT LAKES LATE TONIGHT INTO WEDNESDAY. THIS LOW WILL CONTINUE TO SEND BANDS OF PRECIPITATION ACROSS NORTH-CENTRAL AND NORTHEAST WISCONSIN THROUGH THE END OF THE TAF PERIOD. THE SNOWFALL ACROSS NORTH-CENTRAL WISCONSIN IS ANTICIPATED TO SWITCH BACK TO RAIN EARLY TO MIDDLE AFTERNOON...WHICH WILL HELP VSBYS IMPROVE TO MVFR. HOWEVER...PLENTY OF IFR CIGS ARE LIFTING NORTHWARD ACROSS CENTRAL AND NORTHEAST WISCONSIN AND EXPECT CIGS TO REMAIN IFR THROUGH EARLY THIS EVENING. THEN AS A BROAD SURFACE LOW MOVES INTO THE SOUTHWEST WISCONSIN LATE TONIGHT...WEAKENING WINDS AND AN INFLUX OF MOISTURE WILL LIKELY LOWER CIGS INTO THE LIFR RANGE. DENSE FOG IS ALSO POSSIBLE ALONG THE LAKE MICHIGAN SHORELINE AS THIS OCCURS AS WELL. EXPECT ONLY SLOW IMPROVEMENT OF THE CIGS/VSBSY TOMORROW MORNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......RE AVIATION.......MPC