Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/15/14


AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
910 PM PDT SAT APR 12 2014 .UPDATE... SURFACE OBSERVATIONS IN KERN COUNTY SHOWING HAVE STEADILY SHOWN INCREASING WINDS THIS EVENING AND NOW SEVERAL SPOTS ARE EXCEEDING WIND ADVISORY CRITERIA. HRRR AND ADJMET DATA SUGGEST THIS WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS THEREFORE ISSUED A WIND ADVISORY THROUGH 15Z. OTHERWISE CONVECTIVE ACTIVITY QUICKLY DIMINISHED THIS EVENING AND AT THIS POINT WE/RE JUST LOOKING AT GROUND CLUTTER ON THE 88D. SATELLITE DATA SHOW SKIES HAVE CLEARED OUT AS WELL. GRIDDED DATA ADJUSTED FOR THESE CHANGES AND TRENDS. DRIER AIRMASS TOMORROW WILL INHIBIT ANY APPRECIABLE CAPE FROM DEVELOPING SO NOT EXPECTING ANY ADDITIONAL SHOWERS/STORMS. && .SYNOPSIS... WARM AND DRY TEMPERATURES TO CONTINUE THROUGH THE WEEKEND AND INTO THE WORK WEEK AS WEAK HIGH PRESSURE PREVAILS OVER THE FORECAST AREA. && .DISCUSSION... THE LOW IS EMBEDDED IN AN UPPER-LEVEL TROUGH THAT IS FORECAST TO MOVE ACROSS ARIZONA TONIGHT. A SHORT-WAVE DROPPING INTO THE TROUGH TONIGHT AND SUNDAY WILL KEEP AN EAST-PACIFIC RIDGE OFFSHORE THROUGH SUNDAY...THEN THE RIDGE BUILDS INTO CALIFORNIA SUNDAY NIGHT AND MONDAY. THIS WILL ALLOW TEMPERATURES TO WARM MONDAY BEFORE AN UPPER-LEVEL SHORT-WAVE MOVING INTO THE PACIFIC NORTHWEST KNOCKS THE RIDGE DOWN TUESDAY. 500-MB HEIGHTS OVER THE NORTHERN HALF OF THE HANFORD WARNING/ FORECAST AREA ARE EXPECTED TO FALL BELOW 5700 METERS TUESDAY AFTERNOON AND EVENING. THIS WILL BRING COOLER TEMPERATURES TO THE REGION FOR MIDWEEK BEFORE THE RIDGE REBUILDS INTO THE STATE THURSDAY. ANOTHER TROUGH IS FORECAST TO REACH THE PACIFIC NORTHWEST FRIDAY AND SATURDAY. HOWEVER...THE MODELS DIFFER AS TO EXACT TRACK AND STRENGTH SO NO CHANGES TO THE DAY 6-7 FORECAST AT THIS TIME. && .AVIATION... VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CA INTERIOR THROUGH THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 04-12 96:1908 52:1922 64:1904 34:1953 KFAT 04-13 97:1898 54:1998 59:1936 34:1911 KFAT 04-14 98:1985 52:1956 60:1985 36:1972 KBFL 04-12 98:1908 52:1956 59:1978 33:1903 KBFL 04-13 94:2008 57:2012 59:1930 32:1893 KBFL 04-14 99:1985 56:2003 62:1962 33:1893 && .HNX WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 8 AM PDT SUNDAY CAZ095-098-099. && $$ PUBLIC...INIGUEZ AVN/FW...BSO PREV DISCUSSION...SANGER SYNOPSIS...WP WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
327 PM MDT SUN APR 13 2014 .SHORT TERM...MAIN UPPER TROUGH IS PRESENTLY MOVING OVER THE COLORADO WESTERN SLOPE AND CENTRAL MOUNTAINS. INTENSE SNOW SHOWER ACTIVITY HAS DEVELOPED OVER THE MOUNTAINS WITH SNOWFALL RATES OF ONE TO TWO INCHES PER HOUR IN SUMMIT COUNTY FOR THE LAST COUPLE HOURS. LIGHTNING NETWORKS HAVE SHOWN SOME THUNDERSTORMS OVER GUNNISON AND THE SAN JUAN MOUNTAINS. HAVE ADDED THE MENTION OF ISOLATED THUNDER TO THE MOUNTAIN ZONES FOR THE EARLY PARTS OF THIS EVENING. WITH THE MODERATE AND HEAVY SNOW OCCURRING IN THE MOUNTAINS AT THE PRESENT TIME...WILL CONTINUE ALL OF THE WARNINGS AND ADVISORIES. DEPENDING ON THE PROGRESS OF THE UPPER TROUGH THROUGH THE EVENING HOURS...HIGHLIGHTS MAY BE ABLE TO BE CANCELLED BY MID-EVENING. CONCERNING SNOWFALL AMOUNTS ON THE PLAINS...MESOSCALE AND HI-RES MODELS HAVE TRENDED AWAY FROM AN AREA OF HEAVY SNOW OVER THE NORTHEAST CORNER OF THE STATE. HOWEVER...THE RAP DOES SHOW 3-4+ INCHES OF SNOW ACROSS MOST OF THE PLAINS. WILL NOT ISSUE ANY NEW ADVISORIES...BUT WILL BE MENTIONING 2 TO 5 INCHES OF NEW SNOW IN THE FIRST FORECAST PERIOD. GUSTY NORTH WINDS UP TO 35 MPH SHOULD CONTINUE WELL INTO THE EVENING...SO WILL BE MENTIONING AREAS OF BLOWING SNOW. LATER TONIGHT...THE MODELS ALL POINT TO STRONG SUBSIDENCE BEHIND THIS TROUGH AND RAPID IMPROVEMENT OF WEATHER AFTER MIDNIGHT. TOMORROW WILL CONTINUE DRY WITH SOME WARMING WHICH WILL BE LIMITED BY THE AMOUNTS OF SOIL MOISTURE LEFT OVER FROM TODAY AND TONIGHT SNOW EVENT. .LONG TERM...HIGH PRESSURE RIDGING ALOFT WILL BUILD OVER THE REGION ON MONDAY NIGHT AND TUESDAY. THIS WILL RESULT IN DRYING AND A WARMING TREND WITH READINGS BACK TO NEAR 60 DEGREES OVER LOWER ELEVATIONS ON TUESDAY. THE NEXT UPPER LEVEL DISTURBANCE WILL MOVE INTO COLORADO ON WEDNESDAY THROUGH EARLY THURSDAY WITH THE NEXT CHANCE OF RAIN AND SNOW. THE LONG RANGE MODELS ARE IN A BIT BETTER AGREEMENT TODAY BUT GFS STILL SHOWING THE STRONGEST AND DEEPEST SOLUTION. WITH A BIT BETTER CONTINUITY WILL TREND LOWER TEMPERATURES AND A BIT HIGHER CHANCES OF PRECIP FOR THIS PERIOD. DRY AND WARMER AGAIN FOR LATER IN THE WEEK. && .AVIATION...IFR CONDITIONS WILL PERSIST THROUGH THE EVENING AS THE UPPER DISTURBANCE MOVES FROM THE MOUNTAINS OUT OVER THE PLAINS. EMBEDDED SHOWER ACTIVITY WITHIN THE PRECIPITATION FIELD WILL BE CAPABLE OF PRODUCING MODERATE TO HEAVY SNOW AT TIMES. SNOWFALL RATES MAY EXCEED ONE INCH PER HOUR...BUT WILL GENERATLLY BE LESS THAN ONE-HALF INCH PER HOUR. AS TEMPERATURES COOL IN THE EVENING...ACCUMULATION OF SNOW WILL INCREASE. NORTH WINDS GUSTING TO NEAR 25 KNOTS WILL GENERALLY NOT BE STRONG ENOUGH TO GENERATE ANY BLOWING SNOW. CONDITIONS SHOULD BE IMPROVING BEGIN APPROVING BY ABOUT 03Z WITH SNOW ENDING AROUND 06Z. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ030- 032-037>040-043-045>047. WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ031- 033>036-041. && $$ SHORT TERM...DANKERS LONG TERM....ENTREKIN AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS ALBANY NY
132 AM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL BUILD OFFSHORE AS A WARM FRONT BRINGS SOME CLOUDS AND POSSIBLY A FEW SHOWERS LATE TONIGHT...MAINLY NORTH OF THE CAPITAL REGION. A STRONG SOUTHERLY FLOW WILL BECOME ESTABLISHED TOMORROW AND MONDAY...BRINGING OUR WARMEST WEATHER SINCE EARLY LAST OCTOBER. A STRONG COLD FRONT WILL BRING A ROUND OF RAIN LATE MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 100 AM EDT...RADARS INDICATING SOME SHOWERS STILL TO THE NORTHWEST OF HERKIMER COUNTY...BUT EAST TOWARD NORTHERN HERKIMER COUNTY. THESE SHOWERS ARE ASSOCIATED WITH A MULTI-CONVECTIVE SYSTEM (MCS) WORKING ACROSS ONTARIO AND THE NORTHERN PORTIONS OF LAKE ONTARIO. A WARM FRONT WAS PUSHING INTO NORTHERN PA. ALL OF OUR FORECAST AREA WAS DRY WITH INCREASING HIGH/MID LEVEL CLOUDS. IT LOOKS AS IF THIS MCS WILL IMPACT MAINLY THE ADIRONDACKS AND AREAS NORTH OF THE CAPITAL DISTRICT. HOWEVER...THE HRRR SUGGESTS THAT SHOWERS COULD WORK WELL SOUTH INTO THE CAPITAL REGION BY DAWN. WHILE WE THINK THIS IS LIKELY OVERDONE...WE WILL CONTINUE WITH SLIGHT CHANCES ARE FAR SOUTH AS THE CAPITAL DISTRICT. TEMPERATURES WILL LIKELY NOT FALL AT THAT MUCH MORE OVERNIGHT...AT LEAST FROM THE CAPITAL DISTRICT NORTHWARD...DUE TO AN INCREASE CLOUDS. FURTHER SOUTH...WHERE THE CLOUDS WILL BE THINNEST SO TEMPERATURES COULD DROP SEVERAL MORE DEGREES. OVERNIGHT LOWS LOOK TO BE GENERALLY IN THE 40S...WITH A FEW POCKETS OF UPPER 30S IN SHELTERED MOUNTAIN VALLEY. WE HAVE ADJUSTED A FEW OVERNIGHT LOWS DOWNWARD. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/... ANY LINGERING SCATTERED SHOWER OR ISOLATED THUNDERSTORM ACTIVITY SHOULD END IN THE MORNING AND INCREASING SUNSHINE THROUGH THE AFTERNOON. BOUNDARY LAYER TEMPERATURES CONTINUE TO WARM AND THE WINDS SHOULD BE STEADY...EVEN BREEZY AT TIMES. DECENT MIXING IN THE AFTERNOON SHOULD PUSH TEMPERATURES INTO THE 70S...WITH SOME 60S SOUTHERN ADIRONDACKS AND SOUTHERN GREEN MOUNTAINS...WHERE CLEARING COULD BE DELAYED MOST DUE THE WARM FRONT EXITING THOSE AREAS LAST. PERIODS OF CLOUDS SUNDAY NIGHT ALONG WITH LIGHT SOUTH WINDS AND INCREASING LOW LEVEL MOISTURE SHOULD RESULT IN LOWS IN THE 50S. MORE WARMING MONDAY WITH PERIODS OF MID AND HIGH CLOUDS. HIGHS IN THE 70S TO NEAR 80. SOME INSTABILITY SPREADS ACROSS THE REGION DUE TO THE INCREASING MOISTURE AND BOUNDARY LAYER TEMPERATURES... SO ISOLATED THUNDER IS POSSIBLE AHEAD AND ALONG THE COLD FRONT MONDAY NIGHT AND TUESDAY. BOUNDARY LAYER WIND FIELDS ARE STRONG SO WE WILL HAVE TO SEE IF THERE IS ANY POSSIBILITY FOR STRONG WINDS TO MIX TO THE GROUND IN THUNDERSTORMS. BY LATE MONDAY AFTERNOON AND NIGHT...THE ADVANCING UPPER SYSTEM AND ASSOCIATED COLD FRONT SHOULD SUPPORT DEVELOPMENT OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN WESTERN AREAS...THEN COVERAGE SPREADS TO THE ENTIRE FORECAST AREA THROUGH THE NIGHT. LOWS MONDAY NIGHT IN THE 50S...AROUND 50 SOUTHERN ADIRONDACKS. THE TIMING OF THE COLD FRONT TUESDAY IS A BIT IN QUESTION...BUT SINCE THE UPPER FEATURE IS AN OPEN WAVE...THERE ARE SOME HINTS THAT THE FRONT COULD EXIT OUR FORECAST AREA BY LATE AFTERNOON WITH TEMPERATURES BEGINNING TO FALL THROUGH THE AFTERNOON. REGARDLESS OF THE TIMING...SHOWERS AND ISOLATED THUNDERSTORMS ALONG THE FRONT WITH HIGH TEMPERATURES AROUND 60 TO LOWER 60S BEFORE THE FRONT TRACKS THROUGH. THERE COULD BE SOME ISSUES WITH RIVERS DUE TO RAINFALL AND SNOW MELT WHICH IS DESCRIBED IN THE HYDROLOGY SECTION...AND WILL BE HIGHLIGHTED IN THE HAZARDOUS WEATHER OUTLOOK. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AFTER SOME LINGERING RAIN/SNOW SHOWERS IN THE WAKE OF TUESDAY/S FRONTAL PASSAGE TUE NT/EARLY WED...MUCH BELOW NORMAL TEMPS WILL TAKE HOLD WED...DESPITE FAIR WEATHER. THEREAFTER...A GRADUAL WARMING TREND TOWARD SEASONAL TEMPS WILL RESUME LATER IN THE WEEK AS MID/UPPER LEVEL HEIGHTS RISE. HERE ARE SOME SPECIFICS... TUE NT...THE COLD FRONT SHOULD BE EAST OF THE CWA. HOWEVER...WITH THE MAIN MID/UPPER LEVEL TROUGH REMAINING TO THE WEST...A DISTINCT ANAFRONTAL STRUCTURE SHOULD KEEP PERIODS OF RAIN OR RAIN SHOWERS ACROSS MUCH OF THE REGION EARLY TUE NT...WITH A CHANGE OVER TO SNOW OR A WINTRY MIX ACROSS HIGHER ELEVATIONS OF THE WESTERN ADIRONDACKS...AND EASTERN CATSKILLS. THE PRECIP SHOULD GRADUALLY TAPER OFF FROM W TO E LATER AT NIGHT...BUT AS COLDER AIR CONTINUES TO BUILD INTO THE REGION...ANY PRECIP SHOULD END AS SNOW. SOME MINOR ACCUMS ARE POSSIBLE ACROSS AT LEAST HIGHER ELEVATIONS ACROSS THE REGION...AND DEPENDING ON THE EXACT TIMING OF WHEN THE PRECIP ENDS...CAN NOT RULE OUT SOME MINOR ACCUMS ON COLDER SURFACES EVEN IN SOME VALLEY AREAS. AS LONG AS NO PRONOUNCED WAVES DEVELOP ALONG THE FRONT...THEN SNOWFALL AMTS IN ANY AREA SHOULD REMAIN MINOR. ANY SNOW SHOWERS/FLURRIES SHOULD BECOME CONFINED TO HIGHER ELEVATIONS ACROSS THE SOUTHERN ADIRONDACKS/NORTH COUNTRY AND SOUTHERN VT BY DAYBREAK WED. TEMPS SHOULD FALL INTO THE 20S IN HIGHER ELEVATIONS...AND LOWER 30S IN VALLEYS BY EARLY WED AM. WED-FRI NT...THE UPPER LEVEL TROUGH WILL SWING BY THE REGION RATHER RAPIDLY EARLY WED...WITH RISING HEIGHTS IN ITS WAKE. A SFC HIGH WILL DOMINATE FOR LATER WED INTO FRI. SO...OTHER THAN POSSIBLE LINGERING SNOW SHOWERS ACROSS HIGHER ELEVATIONS WED AM...EXPECT GENERALLY DRY CONDITIONS THROUGH THIS PERIOD. SKIES SHOULD REMAIN GENERALLY CLEAR TO PARTLY CLOUDY...ALTHOUGH CLOUDS MAY BECOME A BIT MORE WIDESPREAD LATE FRI OR FRI NT AS THE LOW LEVEL FLOW BECOMES MORE SOUTHEAST...ALLOWING LOW LEVEL MOISTURE TO BE TRANSPORTED INTO THE REGION FROM THE ATLANTIC OCEAN. TEMPS WILL BE QUITE CHILLY WED-WED NT...WITH MAX TEMPS MAINLY IN THE 40S IN VALLEYS...AND UPPER 20S AND 30S ACROSS HIGHER ELEVATIONS...AND OVERNIGHT MINS IN THE 20S TO LOWER 30S...WITH SOME TEENS POSSIBLE ACROSS PORTIONS OF THE ADIRONDACKS. GRADUAL WARMING IS EXPECTED FOR THU-FRI NT...WITH DAYTIME MAXES REACHING THE 40S TO LOWER 50S ON THU...THEN 50S TO LOWER 60S ON FRI...WARMEST BOTH DAYS IN VALLEY AREAS. OVERNIGHT MINS SHOULD FALL INTO THE 20S AND LOWER 30S THU AM...AND 30S TO AROUND 40 FOR FRI NT/SAT AM. SAT-SAT NT...A SHORTWAVE SLOWLY APPROACHING FROM THE WEST/SOUTHWEST MAY BRING SOME SHOWERS TO THE REGION BY LATE SAT OR SAT NT. WILL INCLUDE SLIGHT CHC POPS. OTHERWISE...A MOISTENING SOUTHEAST/SOUTH LOW LEVEL FLOW SHOULD ALLOW FOR AT LEAST SOME CLOUDS. EXPECT MAX TEMPS TO REACH THE 50S...AND OVERNIGHT MINS TO FALL INTO THE UPPER 30S TO MID 40S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... MAINLY VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE KALB/KPOU/KPSF/KGFL TAF SITES THROUGH THE 24 HOUR TAF PERIOD ENDING 14/06Z. CLOUDS WILL GRADUALLY THICKEN AS A WARM FRONT LIFTS NORTHWARD ACROSS THE REGION OVERNIGHT AND SUNDAY MORNING. CIGS ARE EXPECTED TO LOWER OVERNIGHT...BUT STILL REMAIN IN VFR RANGE. SCATTERED SHOWERS MAY DEVELOP FROM AROUND KGFL-KALB-KPSF TOWARDS 09Z-11Z...SO WILL MENTION VCSH AT KALB/KPSF/KGFL...WITH A TEMPO GROUP FOR MVFR CONDITIONS AT KGFL DUE TO SHOWERS BETWEEN 11Z AND 15Z. SHOWERS ARE EXPECTED TO REMAIN NORTH OF KPOU WITH JUST OVC SKIES. ANY SHOWERS SHOULD LIFT WELL NORTH OF THE ENTIRE REGION BY MID TO LATE MORNING. THERE IS A SLIGHT CHANCE THAT SOME EMBEDDED THUNDERSTORMS COULD OCCUR AT KGFL AROUND OR JUST AFTER DAYBREAK...BUT THE OVERALL PROBABILITY FOR THIS TO OCCUR IS TOO LOW TO MENTION IN THE TAF AT THIS TIME. WINDS WILL BE CALM OR LIGHT AND VARIABLE OVERNIGHT...THEN TREND TO THE SOUTH ON SUNDAY AND INCREASE TO 10-15 KT WITH GUSTS OVER 20 TO 25 KTS...ESPECIALLY AT KALB. LOW LEVEL WIND SHEAR IS POSSIBLE KGFL/KPOU/KPSF FOR A TIME SUNDAY MORNING...AS SFC WINDS REMAIN RELATIVELY LIGHT FROM THE SOUTH TO SOUTHEAST AT LESS THAN 8 KT...WHILE WINDS AROUND 2000-3000 FT AGL INCREASE FROM THE SOUTH TO 35-40 KT. OUTLOOK... LATE SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. MONDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA...TSRA. TUESDAY: HIGH OPERATIONAL IMPACT.WINDY WITH GUSTS TO 33.0 DEFINITE SHRA...TSRA. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY LIKELY SHRA. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... MOST OF THE MOHAWK VALLEY AND CATSKILLS ARE NOW SNOW FREE...WHILE SNOW LINGERS ACROSS THE NORTHERN BERKSHIRES...LAKE GEORGE AREA... THE SOUTHERN GREEN MOUNTAINS AND OF COURSE THE ADIRONDACKS. HIGH PRESSURE WILL BUILD OFFSHORE AS A WARM FRONT BRINGS SOME CLOUDS AND POSSIBLY A FEW SHOWERS LATE TONIGHT...MAINLY NORTH OF THE CAPITAL REGION. A STRONG SOUTHERLY FLOW WILL BECOME ESTABLISHED TOMORROW AND MONDAY...BRINGING OUR WARMEST WEATHER SINCE EARLY LAST OCTOBER. A STRONG COLD FRONT WILL BRING A ROUND OF RAIN LATE MONDAY NIGHT INTO TUESDAY. CLOUDS AND A BREEZE MIGHT PREVENT A FULL RECOVERY OVERNIGHT IN SOME AREAS...BUT THERE ARE CHANCES OF SHOWERS FROM ALBANY NORTH. MOST OF THESE SHOWERS LOOK LIGHT WITH AMOUNTS PROBABLY WELL BELOW A QUARTER OF AN INCH. SUNDAY...A SOUTHERLY BREEZE WILL INCREASE TO BETWEEN 10 AND 20 MPH...GUSTING UP TO 30 MPH IN SOME PLACES. WE EXPECT SOME SUNSHINE AND WARM TEMPERATURES. AFTERNOON RH VALUES WILL BE 35 TO 45 PERCENT SOUTH OF THE MOHAWK VALLEY AND 45 TO 60 PERCENT NORTH OF THE MOHAWK VALLEY. ON SUNDAY NIGHT...RH VALUES RISE TO 80 TO 100 PERCENT AND FALL TO 30 TO 40 PERCENT MONDAY. WIND SPEEDS MONDAY LOOK TO BE SIMILAR TO SUNDAY...WITH SOUTHERLY WINDS 10 TO 20 MPH AND HIGHER GUSTS. THE NEXT CHANCE FOR A SIGNIFICANT WETTING RAIN WILL BE MONDAY NIGHT INTO TUESDAY AS STRONG COLD FRONT SLOWLY WORKS THROUGH THE REGION. && .HYDROLOGY... A FLOOD WARNING REMAINS IN EFFECT FOR THE DELTA DAM ON THE UPPER MOHAWK RIVER UNTIL FURTHER NOTICE...AS RECENT RAINFALL AND SIGNIFICANT SNOW MELT IS EXPECTED TO KEEP THE RESERVOIR ABOVE FLOOD STAGE FOR THE NEXT FEW DAYS. A RIVER FLOOD WARNING HAS ALSO BEEN ISSUED FOR RIVERBANK DUE TO EXPECTED SNOW MELT AND RESULTANT RIVER RISES THIS WEEKEND. OTHER RIVERS IN AND THE ADIRONDACKS...SOUTHERN GREENS...AND BERKSHIRES WILL SEE MINOR DIURNAL RISES DUE TO SNOW MELT. THE ONLY AREAS WHERE SIGNIFICANT RIVER ICE REMAINS ARE THE UPPER HUDSON RIVER AND EAST CANADA CREEK. AT THIS TIME NO SIGNIFICANT ICE JAMS HAVE BEEN REPORTED...AND FLOODING IS NOT ANTICIPATED AT THIS TIME. THERE IS A CHANCE OF SHOWERS TONIGHT INTO SUNDAY...MAINLY NORTH OF THE CAPITAL REGION. WHILE THE SHOWERS THEMSELVES TONIGHT AND SUNDAY LOOK LIGHT...THEY WILL COMBINED WITH VERY MILD TEMPERATURES TO CONTINUE SNOW MELT AND RESULTANT RUNOFF. THEN...A SLOW MOVING COLD FRONT WILL LIKELY BRING MORE SIGNIFICANT RAINFALL MONDAY NIGHT INTO TUESDAY. AT THE VERY LEAST...THIS RAIN ALONG WITH INITIALLY THE WARM TEMPERATURES...WILL LIKELY RESULT IN SIGNIFICANT WITHIN BANK RISES ON MANY RIVERS AND STREAMS. IN OUR NORTHERN AREAS...THE COMBINATION OF RAIN AND SNOW MELT COULD EVEN RESULT IN MINOR TO PERHAPS SOME MODERATE FLOODING ON SOME RIVERS AND STREAMS. ONCE THERE IS BETTER AGREEMENT AS TO THE DEGREE OF SNOW MELT AND RAINFALL AMOUNTS THROUGH TUESDAY...FLOOD WATCHES MAYBE NEED TO BE ISSUED BY THE END OF THE WEEKEND IF CONFIDENCE IN WIDESPREAD FLOODING INCREASES. IT IS ADVISABLE TO STAY TUNED FOR FURTHER UPDATES. 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...NAS NEAR TERM...HWJIV/KL/NAS SHORT TERM...NAS LONG TERM...KL AVIATION...GJM FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
100 AM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL BUILD OFFSHORE AS A WARM FRONT BRINGS SOME CLOUDS AND POSSIBLY A FEW SHOWERS LATE TONIGHT...MAINLY NORTH OF THE CAPITAL REGION. A STRONG SOUTHERLY FLOW WILL BECOME ESTABLISHED TOMORROW AND MONDAY...BRINGING OUR WARMEST WEATHER SINCE EARLY LAST OCTOBER. A STRONG COLD FRONT WILL BRING A ROUND OF RAIN LATE MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 100 AM EDT...RADARS INDICATING SOME SHOWERS STILL TO THE NORTHWEST OF HERKIMER COUNTY...BUT EAST TOWARD NORTHERN HERKIMER COUNTY. THESE SHOWERS ARE ASSOCIATED WITH A MULTI-CONVECTIVE SYSTEM (MCS) WORKING ACROSS ONTARIO AND THE NORTHERN PORTIONS OF LAKE ONTARIO. A WARM FRONT WAS PUSHING INTO NORTHERN PA. ALL OF OUR FORECAST AREA WAS DRY WITH INCREASING HIGH/MID LEVEL CLOUDS. IT LOOKS AS IF THIS MCS WILL IMPACT MAINLY THE ADIRONDACKS AND AREAS NORTH OF THE CAPITAL DISTRICT. HOWEVER...THE HRRR SUGGESTS THAT SHOWERS COULD WORK WELL SOUTH INTO THE CAPITAL REGION BY DAWN. WHILE WE THINK THIS IS LIKELY OVERDONE...WE WILL CONTINUE WITH SLIGHT CHANCES ARE FAR SOUTH AS THE CAPITAL DISTRICT. TEMPERATURES WILL LIKELY NOT FALL AT THAT MUCH MORE OVERNIGHT...AT LEAST FROM THE CAPITAL DISTRICT NORTHWARD...DUE TO AN INCREASE CLOUDS. FURTHER SOUTH...WHERE THE CLOUDS WILL BE THINNEST SO TEMPERATURES COULD DROP SEVERAL MORE DEGREES. OVERNIGHT LOWS LOOK TO BE GENERALLY IN THE 40S...WITH A FEW POCKETS OF UPPER 30S IN SHELTERED MOUNTAIN VALLEY. WE HAVE ADJUSTED A FEW OVERNIGHT LOWS DOWNWARD. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/... ANY LINGERING SCATTERED SHOWER OR ISOLATED THUNDERSTORM ACTIVITY SHOULD END IN THE MORNING AND INCREASING SUNSHINE THROUGH THE AFTERNOON. BOUNDARY LAYER TEMPERATURES CONTINUE TO WARM AND THE WINDS SHOULD BE STEADY...EVEN BREEZY AT TIMES. DECENT MIXING IN THE AFTERNOON SHOULD PUSH TEMPERATURES INTO THE 70S...WITH SOME 60S SOUTHERN ADIRONDACKS AND SOUTHERN GREEN MOUNTAINS...WHERE CLEARING COULD BE DELAYED MOST DUE THE WARM FRONT EXITING THOSE AREAS LAST. PERIODS OF CLOUDS SUNDAY NIGHT ALONG WITH LIGHT SOUTH WINDS AND INCREASING LOW LEVEL MOISTURE SHOULD RESULT IN LOWS IN THE 50S. MORE WARMING MONDAY WITH PERIODS OF MID AND HIGH CLOUDS. HIGHS IN THE 70S TO NEAR 80. SOME INSTABILITY SPREADS ACROSS THE REGION DUE TO THE INCREASING MOISTURE AND BOUNDARY LAYER TEMPERATURES... SO ISOLATED THUNDER IS POSSIBLE AHEAD AND ALONG THE COLD FRONT MONDAY NIGHT AND TUESDAY. BOUNDARY LAYER WIND FIELDS ARE STRONG SO WE WILL HAVE TO SEE IF THERE IS ANY POSSIBILITY FOR STRONG WINDS TO MIX TO THE GROUND IN THUNDERSTORMS. BY LATE MONDAY AFTERNOON AND NIGHT...THE ADVANCING UPPER SYSTEM AND ASSOCIATED COLD FRONT SHOULD SUPPORT DEVELOPMENT OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN WESTERN AREAS...THEN COVERAGE SPREADS TO THE ENTIRE FORECAST AREA THROUGH THE NIGHT. LOWS MONDAY NIGHT IN THE 50S...AROUND 50 SOUTHERN ADIRONDACKS. THE TIMING OF THE COLD FRONT TUESDAY IS A BIT IN QUESTION...BUT SINCE THE UPPER FEATURE IS AN OPEN WAVE...THERE ARE SOME HINTS THAT THE FRONT COULD EXIT OUR FORECAST AREA BY LATE AFTERNOON WITH TEMPERATURES BEGINNING TO FALL THROUGH THE AFTERNOON. REGARDLESS OF THE TIMING...SHOWERS AND ISOLATED THUNDERSTORMS ALONG THE FRONT WITH HIGH TEMPERATURES AROUND 60 TO LOWER 60S BEFORE THE FRONT TRACKS THROUGH. THERE COULD BE SOME ISSUES WITH RIVERS DUE TO RAINFALL AND SNOW MELT WHICH IS DESCRIBED IN THE HYDROLOGY SECTION...AND WILL BE HIGHLIGHTED IN THE HAZARDOUS WEATHER OUTLOOK. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AFTER SOME LINGERING RAIN/SNOW SHOWERS IN THE WAKE OF TUESDAY/S FRONTAL PASSAGE TUE NT/EARLY WED...MUCH BELOW NORMAL TEMPS WILL TAKE HOLD WED...DESPITE FAIR WEATHER. THEREAFTER...A GRADUAL WARMING TREND TOWARD SEASONAL TEMPS WILL RESUME LATER IN THE WEEK AS MID/UPPER LEVEL HEIGHTS RISE. HERE ARE SOME SPECIFICS... TUE NT...THE COLD FRONT SHOULD BE EAST OF THE CWA. HOWEVER...WITH THE MAIN MID/UPPER LEVEL TROUGH REMAINING TO THE WEST...A DISTINCT ANAFRONTAL STRUCTURE SHOULD KEEP PERIODS OF RAIN OR RAIN SHOWERS ACROSS MUCH OF THE REGION EARLY TUE NT...WITH A CHANGE OVER TO SNOW OR A WINTRY MIX ACROSS HIGHER ELEVATIONS OF THE WESTERN ADIRONDACKS...AND EASTERN CATSKILLS. THE PRECIP SHOULD GRADUALLY TAPER OFF FROM W TO E LATER AT NIGHT...BUT AS COLDER AIR CONTINUES TO BUILD INTO THE REGION...ANY PRECIP SHOULD END AS SNOW. SOME MINOR ACCUMS ARE POSSIBLE ACROSS AT LEAST HIGHER ELEVATIONS ACROSS THE REGION...AND DEPENDING ON THE EXACT TIMING OF WHEN THE PRECIP ENDS...CAN NOT RULE OUT SOME MINOR ACCUMS ON COLDER SURFACES EVEN IN SOME VALLEY AREAS. AS LONG AS NO PRONOUNCED WAVES DEVELOP ALONG THE FRONT...THEN SNOWFALL AMTS IN ANY AREA SHOULD REMAIN MINOR. ANY SNOW SHOWERS/FLURRIES SHOULD BECOME CONFINED TO HIGHER ELEVATIONS ACROSS THE SOUTHERN ADIRONDACKS/NORTH COUNTRY AND SOUTHERN VT BY DAYBREAK WED. TEMPS SHOULD FALL INTO THE 20S IN HIGHER ELEVATIONS...AND LOWER 30S IN VALLEYS BY EARLY WED AM. WED-FRI NT...THE UPPER LEVEL TROUGH WILL SWING BY THE REGION RATHER RAPIDLY EARLY WED...WITH RISING HEIGHTS IN ITS WAKE. A SFC HIGH WILL DOMINATE FOR LATER WED INTO FRI. SO...OTHER THAN POSSIBLE LINGERING SNOW SHOWERS ACROSS HIGHER ELEVATIONS WED AM...EXPECT GENERALLY DRY CONDITIONS THROUGH THIS PERIOD. SKIES SHOULD REMAIN GENERALLY CLEAR TO PARTLY CLOUDY...ALTHOUGH CLOUDS MAY BECOME A BIT MORE WIDESPREAD LATE FRI OR FRI NT AS THE LOW LEVEL FLOW BECOMES MORE SOUTHEAST...ALLOWING LOW LEVEL MOISTURE TO BE TRANSPORTED INTO THE REGION FROM THE ATLANTIC OCEAN. TEMPS WILL BE QUITE CHILLY WED-WED NT...WITH MAX TEMPS MAINLY IN THE 40S IN VALLEYS...AND UPPER 20S AND 30S ACROSS HIGHER ELEVATIONS...AND OVERNIGHT MINS IN THE 20S TO LOWER 30S...WITH SOME TEENS POSSIBLE ACROSS PORTIONS OF THE ADIRONDACKS. GRADUAL WARMING IS EXPECTED FOR THU-FRI NT...WITH DAYTIME MAXES REACHING THE 40S TO LOWER 50S ON THU...THEN 50S TO LOWER 60S ON FRI...WARMEST BOTH DAYS IN VALLEY AREAS. OVERNIGHT MINS SHOULD FALL INTO THE 20S AND LOWER 30S THU AM...AND 30S TO AROUND 40 FOR FRI NT/SAT AM. SAT-SAT NT...A SHORTWAVE SLOWLY APPROACHING FROM THE WEST/SOUTHWEST MAY BRING SOME SHOWERS TO THE REGION BY LATE SAT OR SAT NT. WILL INCLUDE SLIGHT CHC POPS. OTHERWISE...A MOISTENING SOUTHEAST/SOUTH LOW LEVEL FLOW SHOULD ALLOW FOR AT LEAST SOME CLOUDS. EXPECT MAX TEMPS TO REACH THE 50S...AND OVERNIGHT MINS TO FALL INTO THE UPPER 30S TO MID 40S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... MAINLY VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE KALB/KPOU/KPSF/KGFL TAF SITES THROUGH THE 24 HOUR TAF PERIOD ENDING 00Z/13 MON. CLOUDS WILL GRADUALLY THICKEN ASSOCIATED WITH A WARM FRONT LIFTING NORTHWARD ACROSS THE REGION OVERNIGHT. CIGS ARE EXPECTED TO LOWER OVERNIGHT...BUT STILL REMAIN IN VFR RANGE. SCATTERED SHOWERS MAY DEVELOP FROM AROUND KGFL-KALB-KPSF TOWARDS 08Z-10Z...SO WILL MENTION VCSH. SHOWERS ARE EXPECTED TO REMAIN NORTH OF KPOU WITH JUST OVC SKIES. ANY SHOWERS SHOULD LIFT WELL NORTH OF THE ENTIRE REGION BY MID TO LATE MORNING. THERE IS A SLIGHT CHANCE THAT SOME EMBEDDED THUNDERSTORMS COULD OCCUR AT KGFL AROUND OR JUST AFTER DAYBREAK...BUT THE OVERALL PROBABILITY FOR THIS TO OCCUR IS TOO LOW FOR MENTION AT THIS TIME. DEPENDING ON IF ENOUGH SHOWERS OCCUR SUNDAY MORNING...THERE IS A SLIGHT CHANCE THAT SOME MVFR CIGS/VSBYS COULD OCCUR AT KGFL FOR A BRIEF PERIOD BEFORE IMPROVING TO VFR SUNDAY AFTERNOON. WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT...THEN TREND INTO THE SOUTH ON SUNDAY AND INCREASE TO 10-15 KT WITH HIGHER GUSTS OVER 20 KT...ESPECIALLY AT KALB. LOW LEVEL WIND SHEAR APPEARS LIKELY AT KGFL/KPOU AND KPSF SUNDAY MORNING...AS SFC WINDS REMAIN RELATIVELY LIGHT FROM THE SOUTH TO SOUTHEAST AT LESS THAN 8 KT...WHILE WINDS AROUND 2000-3000 FT AGL INCREASE FROM THE SOUTH TO 35-40 KT. OUTLOOK... SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. MONDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA...TSRA. TUESDAY: HIGH OPERATIONAL IMPACT.WINDY WITH GUSTS TO 33.0 DEFINITE SHRA...TSRA. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY LIKELY SHRA. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... MOST OF THE MOHAWK VALLEY AND CATSKILLS ARE NOW SNOW FREE...WHILE SNOW LINGERS ACROSS THE NORTHERN BERKSHIRES...LAKE GEORGE AREA... THE SOUTHERN GREEN MOUNTAINS AND OF COURSE THE ADIRONDACKS. HIGH PRESSURE WILL BUILD OFFSHORE AS A WARM FRONT BRINGS SOME CLOUDS AND POSSIBLY A FEW SHOWERS LATE TONIGHT...MAINLY NORTH OF THE CAPITAL REGION. A STRONG SOUTHERLY FLOW WILL BECOME ESTABLISHED TOMORROW AND MONDAY...BRINGING OUR WARMEST WEATHER SINCE EARLY LAST OCTOBER. A STRONG COLD FRONT WILL BRING A ROUND OF RAIN LATE MONDAY NIGHT INTO TUESDAY. CLOUDS AND A BREEZE MIGHT PREVENT A FULL RECOVERY OVERNIGHT IN SOME AREAS...BUT THERE ARE CHANCES OF SHOWERS FROM ALBANY NORTH. MOST OF THESE SHOWERS LOOK LIGHT WITH AMOUNTS PROBABLY WELL BELOW A QUARTER OF AN INCH. SUNDAY...A SOUTHERLY BREEZE WILL INCREASE TO BETWEEN 10 AND 20 MPH...GUSTING UP TO 30 MPH IN SOME PLACES. WE EXPECT SOME SUNSHINE AND WARM TEMPERATURES. AFTERNOON RH VALUES WILL BE 35 TO 45 PERCENT SOUTH OF THE MOHAWK VALLEY AND 45 TO 60 PERCENT NORTH OF THE MOHAWK VALLEY. ON SUNDAY NIGHT...RH VALUES RISE TO 80 TO 100 PERCENT AND FALL TO 30 TO 40 PERCENT MONDAY. WIND SPEEDS MONDAY LOOK TO BE SIMILAR TO SUNDAY...WITH SOUTHERLY WINDS 10 TO 20 MPH AND HIGHER GUSTS. THE NEXT CHANCE FOR A SIGNIFICANT WETTING RAIN WILL BE MONDAY NIGHT INTO TUESDAY AS STRONG COLD FRONT SLOWLY WORKS THROUGH THE REGION. && .HYDROLOGY... A FLOOD WARNING REMAINS IN EFFECT FOR THE DELTA DAM ON THE UPPER MOHAWK RIVER UNTIL FURTHER NOTICE...AS RECENT RAINFALL AND SIGNIFICANT SNOW MELT IS EXPECTED TO KEEP THE RESERVOIR ABOVE FLOOD STAGE FOR THE NEXT FEW DAYS. A RIVER FLOOD WARNING HAS ALSO BEEN ISSUED FOR RIVERBANK DUE TO EXPECTED SNOW MELT AND RESULTANT RIVER RISES THIS WEEKEND. OTHER RIVERS IN AND THE ADIRONDACKS...SOUTHERN GREENS...AND BERKSHIRES WILL SEE MINOR DIURNAL RISES DUE TO SNOW MELT. THE ONLY AREAS WHERE SIGNIFICANT RIVER ICE REMAINS ARE THE UPPER HUDSON RIVER AND EAST CANADA CREEK. AT THIS TIME NO SIGNIFICANT ICE JAMS HAVE BEEN REPORTED...AND FLOODING IS NOT ANTICIPATED AT THIS TIME. THERE IS A CHANCE OF SHOWERS TONIGHT INTO SUNDAY...MAINLY NORTH OF THE CAPITAL REGION. WHILE THE SHOWERS THEMSELVES TONIGHT AND SUNDAY LOOK LIGHT...THEY WILL COMBINED WITH VERY MILD TEMPERATURES TO CONTINUE SNOW MELT AND RESULTANT RUNOFF. THEN...A SLOW MOVING COLD FRONT WILL LIKELY BRING MORE SIGNIFICANT RAINFALL MONDAY NIGHT INTO TUESDAY. AT THE VERY LEAST...THIS RAIN ALONG WITH INITIALLY THE WARM TEMPERATURES...WILL LIKELY RESULT IN SIGNIFICANT WITHIN BANK RISES ON MANY RIVERS AND STREAMS. IN OUR NORTHERN AREAS...THE COMBINATION OF RAIN AND SNOW MELT COULD EVEN RESULT IN MINOR TO PERHAPS SOME MODERATE FLOODING ON SOME RIVERS AND STREAMS. ONCE THERE IS BETTER AGREEMENT AS TO THE DEGREE OF SNOW MELT AND RAINFALL AMOUNTS THROUGH TUESDAY...FLOOD WATCHES MAYBE NEED TO BE ISSUED BY THE END OF THE WEEKEND IF CONFIDENCE IN WIDESPREAD FLOODING INCREASES. IT IS ADVISABLE TO STAY TUNED FOR FURTHER UPDATES. 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...NAS NEAR TERM...HWJIV/KL/NAS SHORT TERM...NAS LONG TERM...KL AVIATION...KL/JPV FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1121 AM CDT SUN APR 13 2014 .DISCUSSION... 417 AM CDT TODAY... EARLY THIS MORNING LOW PRESSURE LIES OVER IOWA WITH A WARM FRONT EXTENDING EAST ACROSS FAR NORTHERN ILLINOIS. THE BOUNDARY WAS DRIVEN SOUTH OVERNIGHT BY CONVECTION/OUTFLOW. ON THE WARM SIDE OF THE FRONT...TEMPERATURES REMAINED IN THE 60S OVERNIGHT...BUT NORTH OF THE FRONT TEMPS QUICKLY FALL OFF INTO THE 40S AND THIS TIGHT THERMAL GRADIENT WILL HOVER ACROSS NORTHERN COUNTIES OF THE STATE THIS MORNING. AS FOR CONVECTION THIS MORNING...THUNDERSTORMS HAVE MOVED EAST OVER LAKE MICHIGAN THIS MORNING WITH STABLE CONDITIONS IN THEIR WAKE AND EXPECT QUIET CONDITIONS TO PERSIST THROUGH THE REMAINDER OF THE MORNING AND EARLY AFTERNOON. COUPLED JET STILL PROGGED TO DEVELOP THIS AFTERNOON WITH MODERATE TO STRONG UPPER LEVEL DIVERGENCE RESULTING IN CYCLOGENENSIS ALONG THE MID MISSISSIPPI VALLEY. ISENTROPIC ASCENT WILL INCREASE THROUGH THE LATE MORNING INTO THE AFTERNOON WITH PRECIP OVERSPREADING NORTHERN ILLINOIS FROM THE WEST. SOUNDINGS STILL INDICATE DEEP SATURATED LAYER WITH PWATS PUSHING TO AROUND 1.4-1.5 INCHES. MODELS IN DECENT AGREEMENT ON PLACEMENT OF AXIS OF HEAVIEST RAIN THIS EVENING AND TONIGHT... STRETCHING FROM EASTERN IOWA TO EAST-CENTRAL WISCONSIN AND CLIPPING NORTH CENTRAL ILLINOIS INCLUDING THE ROCKFORD AREA. HEAVY PRECIP REMAINS A CONCERN THOUGH PRECIP SO FAR HAS UNDERPERFORMED FROM PRIOR EXPECTATIONS AND A PROLONGED PERIOD OF DRY WEATHER OVER NORTH CENTRAL ILLINOIS THE PAST SEVERAL WEEKS WILL HELP MITIGATE THE FLOOD THREAT TO SOME DEGREE. MONDAY... LONGWAVE TROUGH AXIS WILL TRANSLATE EAST ACROSS THE PLAINS MONDAY REACHING THE MISSISSIPPI VALLEY BY THE EVENING. MEANWHILE...COLD ADVECTION INTO THE AREA WILL DRIVE H85 TEMPS DOWN TO AROUND -11C AND SEVERAL SMALLER SCALE DISTURBANCES LIFTING UP THE LEE SIDE OF THE TROUGH WILL RESULT IN RAIN CHANGING OVER TO SNOW ACROSS THE AREA. MODELS HAVE TRENDED MORE BULLISH WITH QPF MONDAY AND CANNOT RULE OUT LIGHT ACCUMULATIONS AT THIS TIME...MAINLY DURING THE LATE AFTERNOON INTO THE EVENING WHEN THE AREA IS BETTER ENTRENCHED IN THE COLD AIR. HIGHS MAY STRUGGLE TO REACH INTO THE LOW 40S FOR MUCH OF THE CWA AND A GUSTY NORTH WIND WILL MAKE IT FEEL CLOSER TO THE FREEZING MARK. TUESDAY THROUGH SATURDAY... GENERALLY QUIET WEATHER EXPECTED TUESDAY AND WEDNESDAY UNDER THE INFLUENCE OF HIGH PRESSURE. BY WEDNESDAY...LOW PRESSURE OVER THE PLAINS WILL HELP SPREAD WARM AIR BACK INTO THE MIDWEST WITH A WARMING TREND THROUGH THURSDAY WHEN TEMPERATURE SHOULD BE CLOSER TO NORMAL. MORE ACTIVE WEATHER MAY RETURN LATE IN THE WEEK INTO THE WEEKEND AS ANOTHER SOUTHWEST LOW LIFTS ACROSS THE MIDWEST BRINGING CHANCES FOR PRECIP AND FLUCTUATING TEMPERATURES. BMD && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * WIND SHIFT TO NORTHEAST AROUND 10 KT ARRIVING BY 1630-17Z. * IFR CIGS ARRIVING BY 18Z AND VSBY LOWERING TO AT LEAST MVFR AND POSSIBLY IFR BY 19Z. * PERIODS OF SHRA/TSRA THIS AFTERNOON AND EVENING...HEAVIEST COULD PRODUCE IFR VSBY. * WINDS TURN NORTH AND GUST TO 25-30 KT LATE THIS EVENING/OVERNIGHT. RC //DISCUSSION...UPDATED 12Z... VERY COMPLEX FORECAST. WEAK PRESSURE PATTERN OVER AREA AT THE MOMENT...WITH WEAK LOW PRESSURE OVER LOWER MICHIGAN AND FRONTAL BOUNDARY SAGGING SOUTHWARD. MAIN CHANGE IN TAF WAS TO BRING SHIFT TO EAST OR NORTHEAST WINDS TO ORD SOONER THAN PREVIOUS FCST AND ALSO INCLUDE MDW IN WIND SHIFT. IT IS POSSIBLE THAT THIS SHIFT COULD OCCUR AS SOON AS 17 OR 18Z. CONFIDENCE IS LOWER IN GYY SEEING SHIFT TO NORTHEAST. IFR CIGS BEHIND THE FRONT ACROSS WI SO THESE SHOULD DEVELOP SOMETIME AFTER THE SHIFT TO EASTERLY WINDS. ITS POSSIBLE THAT WINDS WILL REMAIN EASTERLY UNTIL EARLY EVENING NOW AT ORD/MDW. OTHER CHALLENGE IS WITH SHRA/TSRA TRENDS...AS A COMPLEX LIFTS NORTHEAST FROM IOWA. IT APPEARS THAT THE SHOWERS AND AT LEAST OCNL EMBEDDED THUNDER WILL ARRIVE A BIT SOONER AT THE EASTERN TERMINALS...BUT DURATION COULD BE SHORTER THAN INDICATED IN TEMPO GROUP IN TAF. WILL CONTINUE TO ASSESS OBSERVATIONAL AND RADAR TRENDS FOR UPDATES TO WIND/CIG/AND SHRA/TSRA FORECAST. FROM 12Z... LOW PRESSURE IS OVER THE SOUTHERN PLAINS WITH A FRONT EXTENDING THROUGH NORTHERN IL/SOUTHERN WI. THE FRONT WILL MEANDER TODAY AND THINKING IT WILL IMPACT RFD...ORD...AND DPA. WINDS WILL TURN N TO NE BEHIND THE FRONT...AND BE SOUTH AHEAD OF THE FRONT. RAIN AND STORMS SPREAD NORTH ACROSS THE TERMINALS EARLY THIS AFTN WITH CHANCES OF THUNDERSTORMS INCREASING LATE THIS AFTN INTO THIS EVENING. CIGS WILL LOWER THIS EVENING TO IFR AND THE STRONGEST SHOWERS AND TSRA WILL LIKELY PRODUCE IFR VSBY. INSTABILITY WEAKENS AND SHIFTS SE AS THE LOW MOVES THROUGH THE REGION LATE THIS EVENING. THEREFORE EXPECTING LIMITED TSRA LATE THIS EVENING AND JUST SHRA OVERNIGHT. WINDS WILL ALSO TURN NORTH BEHIND THE LOW AND BEGIN GUSTING. THE HIGHEST GUSTS WILL BE SEEN AT GYY WITH MAX GUSTS OVER 35 KT PSBL. THE OTHER TERMINALS SHOULD SEE GUSTS BTWN 25 AND 30 KT. THE LOWER ATMOSPHERE BEGINS TO DRY MID MONDAY MORNING AND CIGS LIFT TO MVFR. JEE //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE IN WIND SHIFT TO NORTHEAST...LOW-MEDIUM CONFIDENCE IN TIMING OF SHIFT BACK TO SOUTH-SOUTHWEST THIS EVENING. * HIGH CONFIDENCE IN IFR CIGS...MEDIUM-HIGH IN ARRIVAL BY 1730-18Z. * HIGH IN VSBY LOWERING TO MVFR IN BR...MEDIUM IN TIMING...AND MEDIUM IN POTENTIAL FOR IFR VSBY IN BR AND HEAVIEST SHRA/TSRA. * MEDIUM CONFIDENCE IN OVERALL SHRA/TSRA TRENDS AND TIMING THIS AFTERNOON AND EVENING...WITH MEDIUM-HIGH CONFIDENCE THERE WILL BE AT LEAST OCNL TSRA AT THE TERMINALS BY MID AFTERNOON. * HIGH CONFIDENCE IN SHIFT TO GUSTY NORTHERLY WINDS LATE TONIGHT...MEDIUM IN TIMING. RC //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...-RASN PSBLY BCMG -SN AFTER MIDNIGHT. MVFR TO IFR CIGS IMPROVING TO VFR. TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF RAIN OVERNIGHT...MVFR/IFR CIGS PSBL OVERNIGHT. FRIDAY...CHANCE OF RAIN...MVFR TO IFR CIGS PSBL. SATURDAY...CHANCE OF RAIN. JEE && .MARINE... 317 AM CDT HEADLINES...WILL UPGRADE THE GALE WATCHES TO WARNINGS AS GALES ARE STILL EXPECTED. LOW PRESSURE IS OVER THE OK PANHANDLE EARLY THIS MORNING WITH A BROAD TROUGH EXTENDING ALL THE WAY THROUGH THE IL/WI STATE LINE. THERE IS A FRONT IN THE TROUGH BUT IT HOLDS A VARIETY OF FORMS AKA COLD/STATIONARY/WARM AS YOU MOVE ALONG IT...SO WILL REFER TO IT AS A TROUGH FOR SIMPLICITY. THE FRONT WILL MEANDER OVER THE FAR SOUTHERN END OF THE LAKE THIS MORNING WHILE THE LOW MOVES UP THE TROUGH AND PASSES OVER THE SOUTHERN END OF THE LAKE THIS EVENING. NORTH GALES WILL DEVELOP BEHIND THE LOW AND EXTEND THROUGH THE NSH WATERS TONIGHT AND THROUGH MID AFTN MONDAY. WINDS CONTINUE TO DIMINISH THROUGH TUESDAY AS A RIDGE OF HIGH PRESSURE MOVES OVER THE LAKE TUESDAY NIGHT. WINDS TURN SOUTH BEHIND THE RIDGE AND INCREASE TO 30 KT AS A WEAKENING TROUGH OF LOW PRESSURE APPROACHES WEDNESDAY. THE TROUGH PASSES OVER THE LAKE THURSDAY WITH NORTHEAST TO EAST WINDS BEHIND IT. GUIDANCE THEN FEATURES EXTREME DIFFERENCES IN THE PATTERN LATE IN THE WEEK SO HAVE LOW CONFIDENCE IN THE FORECAST PAST THURSDAY. FOR REFERENCE THE ECMWF FEATURES A HIGH MOVING OVER THE LAKE LATE THIS WEEK WHILE THE GFS HAS A LOW MOVING UP THE LAKE AT THE SAME TIME. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...4 PM SUNDAY TO 4 AM MONDAY. GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...4 AM MONDAY TO 4 PM MONDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874...10 PM SUNDAY TO 3 PM MONDAY. GALE WARNING...LMZ080-LMZ675-LMZ777-LMZ779-LMZ876-LMZ878...3 AM MONDAY TO 3 PM MONDAY. && $$ 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 1045 AM CDT Sun Apr 13 2014 .DISCUSSION... ISSUED 1045 AM CDT Sun Apr 13 2014 Will update the forecast to have higher chances of showers and thunderstorms further east into central IL today as area of showers and a few thunderstorms already covering areas west of I-57 and from I-74 sw. SPC expanded slight risk of severe thunderstorms this afternoon and evening to areas west of I-57. Southeast IL se of I-70 should mostly be dry today. Highs this afternoon range from around 70 nw of the IL river to the upper 70s over southeast IL. South winds 15 to 25 mph and gusts of 25 to 35 mph today and strongest over eastern IL. Frontal boundary to stay nw of central IL into this evening and then cold front to push east through IL overnight and thru southeast IL early Monday morning. 07 && .AVIATION... ISSUED 633 AM CDT Sun Apr 13 2014 A rather challenging forecast for this TAF period. Showers and thunderstorms expected to increase in coverage across west central Illinois this morning, but will likely take most of the day to reach as far east as KCMI. Ceilings currently VFR at all TAF sites and even as far back as central Missouri, where the rain is moving in from. Ceiling progs from the RAP and HRRR models showing some brief lowering into MVFR at times, with forecast soundings becoming more favorable for this toward mid afternoon as the rain becomes more widespread, especially KBMI-KSPI westward. There will be some thunder at times, but still some question as to how widespread it will be, so will leave VCTS mention for now. A sharp cold front will be moving across the TAF sites from around 06-10Z, with winds turning northwest and ceilings falling to IFR range. Winds expected to become gusty around mid morning, with the highest gusts this afternoon around 30 knots. Geelhart && .PREV DISCUSSION... ISSUED 249 AM CDT Sun Apr 13 2014 SHORT TERM...Today through Tuesday Frontal boundary currently extending from the southern Great Lakes west-southwestward across Iowa into northern Kansas will serve as the primary focusing mechanism for convection over the next 24 hours. One round of showers/storms aided by 55 to 60kt LLJ has lifted into southern Wisconsin/far northern Illinois, while additional storms are beginning to develop further southwest around the Kansas City area in advance of an upper short-wave tracking out of the southern Rockies. As this feature pushes further eastward, showers and thunderstorms will become more numerous across the Mississippi River Valley into west-central Illinois later this morning. Models continue to suggest that the far E/SE KILX CWA will remain dry throughout the day, so have confined POPs to locations west of a Danville to Effingham line. Will be a windy and warm day as well, with southerly winds gusting to between 30 and 35 mph. Afternoon high temperatures will range from around 70 west of the Illinois River, to the upper 70s south of I-70. As cold front progresses eastward into the region, occasional showers and thunderstorms are expected across the board tonight. With strong convergence along the boundary, ample upper support from the advancing short-wave, and precipitable water values approaching 1.50, locally heavy rainfall will be likely. Despite the threat for high rainfall rates within the storms, the risk for severe weather will be minimal, as strongest instability/low-level wind shear will remain focused further southwest from the Ozarks into east Texas. Cold front will push into Indiana by Monday morning, followed by windy and sharply colder conditions. High temperatures will occur during the morning hours, with readings dropping into the upper 30s/lower 40s during the afternoon. Brisk northwesterly winds gusting to between 25 and 30 mph will make it feel even colder, with wind-chill values dipping into the upper 20s/lower 30s. In addition, approaching northern-stream short-wave will keep precip chances alive despite FROPA. Thermal profiles suggest light rain showers may mix with snow along/west of I-55 during the afternoon as 850mb temps drop into the -4 to -8C range. NAM continues to be the most aggressive in developing snow across central Illinois late Monday afternoon into Monday evening, while all other models are much lighter with the QPF within the cold airmass. Given presence of upper support and adequate moisture profiles, will carry a chance for snow-showers north of I-70 Monday evening. Any accumulations will be minor and mainly confined to grassy surfaces after dark. Once this wave passes, skies will gradually clear from west to east overnight, allowing lows to drop below freezing. LONG TERM...Wednesday through Saturday After cold and dry conditions on Tuesday with highs only reaching the 40s, rising upper heights will allow temperatures to warm back into the 60s by Thursday. Next system of interest is beginning to come into better focus, with the 00z Apr 13 ECMWF coming into better agreement with prior runs of the GFS. Both models now bring an upper wave and its associated frontal boundary into central Illinois on Friday. Despite decent upper dynamics, instability appears meager with this system, so will not mention thunder at this time. Will bring chance POPs for showers into the western half of the CWA Thursday night, then everywhere on Friday. After that, a return to dry weather and near normal temperatures in the 60s can be expected for Saturday. Barnes && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
707 AM CDT SUN APR 13 2014 .DISCUSSION... 417 AM CDT TODAY... EARLY THIS MORNING LOW PRESSURE LIES OVER IOWA WITH A WARM FRONT EXTENDING EAST ACROSS FAR NORTHERN ILLINOIS. THE BOUNDARY WAS DRIVEN SOUTH OVERNIGHT BY CONVECTION/OUTFLOW. ON THE WARM SIDE OF THE FRONT...TEMPERATURES REMAINED IN THE 60S OVERNIGHT...BUT NORTH OF THE FRONT TEMPS QUICKLY FALL OFF INTO THE 40S AND THIS TIGHT THERMAL GRADIENT WILL HOVER ACROSS NORTHERN COUNTIES OF THE STATE THIS MORNING. AS FOR CONVECTION THIS MORNING...THUNDERSTORMS HAVE MOVED EAST OVER LAKE MICHIGAN THIS MORNING WITH STABLE CONDITIONS IN THEIR WAKE AND EXPECT QUIET CONDITIONS TO PERSIST THROUGH THE REMAINDER OF THE MORNING AND EARLY AFTERNOON. COUPLED JET STILL PROGGED TO DEVELOP THIS AFTERNOON WITH MODERATE TO STRONG UPPER LEVEL DIVERGENCE RESULTING IN CYCLOGENENSIS ALONG THE MID MISSISSIPPI VALLEY. ISENTROPIC ASCENT WILL INCREASE THROUGH THE LATE MORNING INTO THE AFTERNOON WITH PRECIP OVERSPREADING NORTHERN ILLINOIS FROM THE WEST. SOUNDINGS STILL INDICATE DEEP SATURATED LAYER WITH PWATS PUSHING TO AROUND 1.4-1.5 INCHES. MODELS IN DECENT AGREEMENT ON PLACEMENT OF AXIS OF HEAVIEST RAIN THIS EVENING AND TONIGHT... STRETCHING FROM EASTERN IOWA TO EAST-CENTRAL WISCONSIN AND CLIPPING NORTH CENTRAL ILLINOIS INCLUDING THE ROCKFORD AREA. HEAVY PRECIP REMAINS A CONCERN THOUGH PRECIP SO FAR HAS UNDERPERFORMED FROM PRIOR EXPECTATIONS AND A PROLONGED PERIOD OF DRY WEATHER OVER NORTH CENTRAL ILLINOIS THE PAST SEVERAL WEEKS WILL HELP MITIGATE THE FLOOD THREAT TO SOME DEGREE. MONDAY... LONGWAVE TROUGH AXIS WILL TRANSLATE EAST ACROSS THE PLAINS MONDAY REACHING THE MISSISSIPPI VALLEY BY THE EVENING. MEANWHILE...COLD ADVECTION INTO THE AREA WILL DRIVE H85 TEMPS DOWN TO AROUND -11C AND SEVERAL SMALLER SCALE DISTURBANCES LIFTING UP THE LEE SIDE OF THE TROUGH WILL RESULT IN RAIN CHANGING OVER TO SNOW ACROSS THE AREA. MODELS HAVE TRENDED MORE BULLISH WITH QPF MONDAY AND CANNOT RULE OUT LIGHT ACCUMULATIONS AT THIS TIME...MAINLY DURING THE LATE AFTERNOON INTO THE EVENING WHEN THE AREA IS BETTER ENTRENCHED IN THE COLD AIR. HIGHS MAY STRUGGLE TO REACH INTO THE LOW 40S FOR MUCH OF THE CWA AND A GUSTY NORTH WIND WILL MAKE IT FEEL CLOSER TO THE FREEZING MARK. TUESDAY THROUGH SATURDAY... GENERALLY QUIET WEATHER EXPECTED TUESDAY AND WEDNESDAY UNDER THE INFLUENCE OF HIGH PRESSURE. BY WEDNESDAY...LOW PRESSURE OVER THE PLAINS WILL HELP SPREAD WARM AIR BACK INTO THE MIDWEST WITH A WARMING TREND THROUGH THURSDAY WHEN TEMPERATURE SHOULD BE CLOSER TO NORMAL. MORE ACTIVE WEATHER MAY RETURN LATE IN THE WEEK INTO THE WEEKEND AS ANOTHER SOUTHWEST LOW LIFTS ACROSS THE MIDWEST BRINGING CHANCES FOR PRECIP AND FLUCTUATING TEMPERATURES. BMD && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * SECOND ROUND OF SHRA/TSRA ARRIVES EARLY THIS AFTN...WITH BEST CHANCE OF TSRA IN THE LATE AFTN/EVENING. * POTENTIAL FOR MULTIPLE WIND SHIFTS OVERNIGHT THROUGH THIS EVENING. * HEAVIER SHRA/TSRA MAY PRODUCE IFR VSBY. * IFR CIGS EXPECTED LATE THIS AFTN/EARLY EVENING. * WINDS TURN NORTH AND GUST TO 25-30 KT LATE THIS EVENING/OVERNIGHT. JEE //DISCUSSION...UPDATED 12Z... LOW PRESSURE IS OVER THE SOUTHERN PLAINS WITH A FRONT EXTENDING THROUGH NORTHERN IL/SOUTHERN WI. THE FRONT WILL MEANDER TODAY AND THINKING IT WILL IMPACT RFD...ORD...AND DPA. WINDS WILL TURN N TO NE BEHIND THE FRONT...AND BE SOUTH AHEAD OF THE FRONT. RAIN AND STORMS SPREAD NORTH ACROSS THE TERMINALS EARLY THIS AFTN WITH CHANCES OF THUNDERSTORMS INCREASING LATE THIS AFTN INTO THIS EVENING. CIGS WILL LOWER THIS EVENING TO IFR AND THE STRONGEST SHOWERS AND TSRA WILL LIKELY PRODUCE IFR VSBY. INSTABILITY WEAKENS AND SHIFTS SE AS THE LOW MOVES THROUGH THE REGION LATE THIS EVENING. THEREFORE EXPECTING LIMITED TSRA LATE THIS EVENING AND JUST SHRA OVERNIGHT. WINDS WILL ALSO TURN NORTH BEHIND THE LOW AND BEGIN GUSTING. THE HIGHEST GUSTS WILL BE SEEN AT GYY WITH MAX GUSTS OVER 35 KT PSBL. THE OTHER TERMINALS SHOULD SEE GUSTS BTWN 25 AND 30 KT. THE LOWER ATMOSPHERE BEGINS TO DRY MID MONDAY MORNING AND CIGS LIFT TO MVFR. JEE //ORD AND MDW CONFIDENCE...UPDATED 12Z... * MEDIUM-HIGH CONFIDENCE IN WINDS REMAINING SOUTHERLY THROUGH THIS MORNING. * HIGH CONFIDENCE IN WINDS SHIFTING DURING THE DAY...LOW CONFIDENCE IN WHEN AND HOW MANY WIND SHIFTS THERE WILL BE THROUGH THIS EVENING. * MEDIUM-HIGH CONFIDENCE IN PRECIP CHANCES INCREASING LATE TODAY INTO THIS EVENING. * HIGH CONFIDENCE IFR CONDITIONS DEVELOPING LATE TODAY OR THIS EVENING...BUT MEDIUM CONFIDENCE ON TIMING. JEE //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...-RASN PSBLY BCMG -SN AFTER MIDNIGHT. MVFR TO IFR CIGS IMPROVING TO VFR. TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF RAIN OVERNIGHT...MVFR/IFR CIGS PSBL OVERNIGHT. FRIDAY...CHANCE OF RAIN...MVFR TO IFR CIGS PSBL. SATURDAY...CHANCE OF RAIN. JEE && .MARINE... 317 AM CDT HEADLINES...WILL UPGRADE THE GALE WATCHES TO WARNINGS AS GALES ARE STILL EXPECTED. LOW PRESSURE IS OVER THE OK PANHANDLE EARLY THIS MORNING WITH A BROAD TROUGH EXTENDING ALL THE WAY THROUGH THE IL/WI STATE LINE. THERE IS A FRONT IN THE TROUGH BUT IT HOLDS A VARIETY OF FORMS AKA COLD/STATIONARY/WARM AS YOU MOVE ALONG IT...SO WILL REFER TO IT AS A TROUGH FOR SIMPLICITY. THE FRONT WILL MEANDER OVER THE FAR SOUTHERN END OF THE LAKE THIS MORNING WHILE THE LOW MOVES UP THE TROUGH AND PASSES OVER THE SOUTHERN END OF THE LAKE THIS EVENING. NORTH GALES WILL DEVELOP BEHIND THE LOW AND EXTEND THROUGH THE NSH WATERS TONIGHT AND THROUGH MID AFTN MONDAY. WINDS CONTINUE TO DIMINISH THROUGH TUESDAY AS A RIDGE OF HIGH PRESSURE MOVES OVER THE LAKE TUESDAY NIGHT. WINDS TURN SOUTH BEHIND THE RIDGE AND INCREASE TO 30 KT AS A WEAKENING TROUGH OF LOW PRESSURE APPROACHES WEDNESDAY. THE TROUGH PASSES OVER THE LAKE THURSDAY WITH NORTHEAST TO EAST WINDS BEHIND IT. GUIDANCE THEN FEATURES EXTREME DIFFERENCES IN THE PATTERN LATE IN THE WEEK SO HAVE LOW CONFIDENCE IN THE FORECAST PAST THURSDAY. FOR REFERENCE THE ECMWF FEATURES A HIGH MOVING OVER THE LAKE LATE THIS WEEK WHILE THE GFS HAS A LOW MOVING UP THE LAKE AT THE SAME TIME. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...4 PM SUNDAY TO 4 AM MONDAY. GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...4 AM MONDAY TO 4 PM MONDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874...10 PM SUNDAY TO 3 PM MONDAY. GALE WARNING...LMZ080-LMZ675-LMZ777-LMZ779-LMZ876-LMZ878...3 AM MONDAY TO 3 PM MONDAY. && $$ 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 634 AM CDT Sun Apr 13 2014 .DISCUSSION... ISSUED 249 AM CDT Sun Apr 13 2014 SHORT TERM...Today through Tuesday Frontal boundary currently extending from the southern Great Lakes west-southwestward across Iowa into northern Kansas will serve as the primary focusing mechanism for convection over the next 24 hours. One round of showers/storms aided by 55 to 60kt LLJ has lifted into southern Wisconsin/far northern Illinois, while additional storms are beginning to develop further southwest around the Kansas City area in advance of an upper short-wave tracking out of the southern Rockies. As this feature pushes further eastward, showers and thunderstorms will become more numerous across the Mississippi River Valley into west-central Illinois later this morning. Models continue to suggest that the far E/SE KILX CWA will remain dry throughout the day, so have confined POPs to locations west of a Danville to Effingham line. Will be a windy and warm day as well, with southerly winds gusting to between 30 and 35 mph. Afternoon high temperatures will range from around 70 west of the Illinois River, to the upper 70s south of I-70. As cold front progresses eastward into the region, occasional showers and thunderstorms are expected across the board tonight. With strong convergence along the boundary, ample upper support from the advancing short-wave, and precipitable water values approaching 1.50, locally heavy rainfall will be likely. Despite the threat for high rainfall rates within the storms, the risk for severe weather will be minimal, as strongest instability/low-level wind shear will remain focused further southwest from the Ozarks into east Texas. Cold front will push into Indiana by Monday morning, followed by windy and sharply colder conditions. High temperatures will occur during the morning hours, with readings dropping into the upper 30s/lower 40s during the afternoon. Brisk northwesterly winds gusting to between 25 and 30 mph will make it feel even colder, with wind-chill values dipping into the upper 20s/lower 30s. In addition, approaching northern-stream short-wave will keep precip chances alive despite FROPA. Thermal profiles suggest light rain showers may mix with snow along/west of I-55 during the afternoon as 850mb temps drop into the -4 to -8C range. NAM continues to be the most aggressive in developing snow across central Illinois late Monday afternoon into Monday evening, while all other models are much lighter with the QPF within the cold airmass. Given presence of upper support and adequate moisture profiles, will carry a chance for snow-showers north of I-70 Monday evening. Any accumulations will be minor and mainly confined to grassy surfaces after dark. Once this wave passes, skies will gradually clear from west to east overnight, allowing lows to drop below freezing. LONG TERM...Wednesday through Saturday After cold and dry conditions on Tuesday with highs only reaching the 40s, rising upper heights will allow temperatures to warm back into the 60s by Thursday. Next system of interest is beginning to come into better focus, with the 00z Apr 13 ECMWF coming into better agreement with prior runs of the GFS. Both models now bring an upper wave and its associated frontal boundary into central Illinois on Friday. Despite decent upper dynamics, instability appears meager with this system, so will not mention thunder at this time. Will bring chance POPs for showers into the western half of the CWA Thursday night, then everywhere on Friday. After that, a return to dry weather and near normal temperatures in the 60s can be expected for Saturday. Barnes && .AVIATION... ISSUED 633 AM CDT Sun Apr 13 2014 A rather challenging forecast for this TAF period. Showers and thunderstorms expected to increase in coverage across west central Illinois this morning, but will likely take most of the day to reach as far east as KCMI. Ceilings currently VFR at all TAF sites and even as far back as central Missouri, where the rain is moving in from. Ceiling progs from the RAP and HRRR models showing some brief lowering into MVFR at times, with forecast soundings becoming more favorable for this toward mid afternoon as the rain becomes more widespread, especially KBMI-KSPI westward. There will be some thunder at times, but still some question as to how widespread it will be, so will leave VCTS mention for now. A sharp cold front will be moving across the TAF sites from around 06-10Z, with winds turning northwest and ceilings falling to IFR range. Winds expected to become gusty around mid morning, with the highest gusts this afternoon around 30 knots. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
WIND. AS THE PREVIOUS FORECAST DISCUSSED...VERY VERY VERY LOW
CONFIDENCE IN WIND DIRECTION FOR THE EASTERN TERMINALS. THE COLD
FRONT COULD STILL SHIFT SOUTH IF THE LINE OF STORMS MOVES THROUGH. THE MAJORITY OF GUIDANCE CONTINUES TO FEATURE SOUTH WINDS. SOME OF THE HI-RES GUIDANCE ALSO CONTINUES TO INDICATE THE COLD FRONT COULD MOVE AROUND TOMORROW AND TEMPORARILY SHIFT WINDS AT ORD NE. WITH VERY LOW CONFIDENCE AND NO GOOD REASON TO MAKE CHANGES...LEFT WINDS IN THE TAFS ALONE. NEXT ROUND OF SHRA/TSRA MOVES IN EARLY IN THE AFTN WITH TSRA AND HEAVY RAIN PSBL. PREVIOUS TIMING IN THE GRIDS LOOKED GOOD AND THINKING A PROB30 FOR TSRA WAS THE BEST WAY TO HANDLE THE SITUATION. MOVED THE POSSIBILITY OF IFR CIGS UP AS WELL AND EXTENDED THE IFR CIGS THROUGH THE OVERNIGHT HOURS AS WELL. JEE //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN SHRA/TSRA IMPACTING ORD/MDW OVERNIGHT. * MEDIUM-HIGH CONFIDENCE IN WINDS REMAINING SOUTHERLY THROUGH LATE TONIGHT. * ABSOLUTELY NO CONFIDENCE IN WIND DIRECTION FORECAST SUNDAY INTO SUNDAY EVENING. * MEDIUM CONFIDENCE IN PRECIP CHANCES INCREASING LATE SUNDAY INTO SUNDAY EVENING. * MEDIUM-HIGH CONFIDENCE IFR CONDITIONS DEVELOPING LATE SUNDAY OR SUNDAY EVENING...BUT LOW CONFIDENCE ON TIMING. JEE //OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z... MONDAY...RAIN LIKELY EARLY. IFR LIKELY. CHANCE OF RAIN OR SNOW MON AFTERNOON AND EVENING. MODERATELY STRONG NORTH WINDS. TUESDAY...MVFR CIGS POSSIBLE...MAINLY EARLY. WEDNESDAY AND THURSDAY...VFR PROBABLE. FRIDAY...CHANCE OF RAIN. IFR POSSIBLE. IZZI && .MARINE... 215 PM CDT A VERY ACTIVE WEATHER PERIOD IS STILL EXPECTED OVER THE LAKE THROUGH MONDAY. A STORM SYSTEM...CURRENT ACROSS THE PLAINS...IS EXPECTED TO MOVE ACROSS THE CENTRAL PORTION OF THE LAKE LATE TONIGHT. THIS LOW WILL DRAPE A FRONTAL BOUNDARY ACROSS THE SOUTHERN SECTIONS OF THE LAKE ON SUNDAY...JUST PRIOR TO ANOTHER AREA OF LOW PRESSURE TRANSITIONING NORTHEASTWARD ACROSS SOUTHERN LAKE MICHIGAN ALONG THIS FRONTAL BOUNDARY SUNDAY NIGHT INTO MONDAY. OVERALL...THIS WILL RESULT IN A RATHER COMPLEX WIND FORECAST ACROSS THE LAKE OVER THE NEXT COUPLE OF DAYS. THIS WILL CREATE LARGE VARIATIONS IN WIND SPEEDS AND DIRECTIONS ACROSS DIFFERENT SECTIONS OF THE LAKE. EASTERLY WINDS WILL GRADUALLY SHIFT OUT OF THE NORTH ACROSS THE NORTHERN 1/3 OF THE LAKE TONIGHT INTO SUNDAY AS THIS FIRST LOW PASSES OVER THE LAKE. THE TRAILING FRONTAL BOUNDARY WILL THEN SLOWLY SHIFT SOUTHWARD ACROSS THE SOUTHERN TIP OF THE LAKE SUNDAY NIGHT...THEN SHIFT OVER THE ENTIRE LAKE BY MONDAY MORNING AS THE SECOND LOW PASSES. THE MAIN CONCERNS THROUGH THE DAY SUNDAY...AS FAR AS HEADLINE CRITERIA WINDS...WILL BE THE THREAT FOR SMALL CRAFT ADVISORY WINDS CONTINUING ON SUNDAY...ESPECIALLY ACROSS THE INDIANA NEAR SHORE WATERS. STRONG SOUTH WINDS MAY CONTINUE HERE AS THE FRONTAL BOUNDARY LOOKS TO REMAIN FARTHER NORTH FOR MUCH OF THE DAY. THIS COULD AGAIN RESULT IN GUSTS UP TO 25 TO 30 KT DURING THE SUNDAY...POSSIBLY REQUIRING THE CURRENT SMALL CRAFT TO BE EXTENDED INTO SUNDAY. HOWEVER...AT THIS TIME I WILL HOLD OFF ON DOING THIS. CONCERNS WILL QUICKLY TRANSITION TO THE GOOD POTENTIAL FOR NORTHERLY GALES IN THE WAKE OF THIS SECOND LOW SUNDAY NIGHT INTO MONDAY. MUCH COLD AIR IS EXPECTED TO SPILL OVER THE LAKE ALONG THE BACK SIDE OF THE IS LOW. IN ADDITION...A RATHER STOUT SURFACE RIDGE OF HIGH PRESSURE IS EXPECTED TO QUICKLY BUILD IN ACROSS THE UPPER MIDWEST LATE SUNDAY NIGHT IN THE WAKE OF THIS LOW. THIS SHOULD RESULT IN A STRENGTHENING PRESSURE GRADIENT...WHICH COULD SUPPORT AROUND 40 KT NORTHERLY GALES FOR A PERIOD LATE SUNDAY NIGHT INTO MONDAY. I HAVE OPTED TO ISSUE A GALE WATCH FOR THIS PERIOD DUE TO THE RELATIVELY HIGH CONFIDENCE IN A PERIOD OF GALE FORCE WINDS. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WILMETTE HARBOR TO MICHIGAN CITY IN UNTIL 4 AM SUNDAY. GALE WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...4 AM MONDAY TO 4 PM MONDAY. GALE WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ669-LMZ671-LMZ868-LMZ870-LMZ872...10 PM SUNDAY TO 3 PM MONDAY. GALE WATCH...LMZ080-LMZ673-LMZ675-LMZ777-LMZ779-LMZ874-LMZ876- LMZ878...3 AM MONDAY TO 3 PM MONDAY. && $$ 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 1150 PM CDT Sat Apr 12 2014 .DISCUSSION... ISSUED 900 PM CDT Sat Apr 12 2014 Latest hourly runs of the HRRR and RAP models suggest that forecast area will remain dry through the night, with the shower/storm threat increasing from the northwest after sunrise Sunday. This is a drier solution than some of the earlier runs, as well as most of the synoptic model runs. Feel this drier trend is the way to go. The local airmass, per 00Z KILX and forecast soundings, is quite dry, and there is not expected to be significant moisture advection into the area overnight. In fact, the low level flow in our area is expected to diminish for a time later tonight, with the best low level inflow apt to remain into the frontal zone to our northwest. This is where significant convection has blown up over the past few hours. The main threat for any precipitation reaching the forecast area before daybreak is if a significant cold pool can develop with the storms to the northwest and help them propagate to the southeast. Even if this were to occur, the storms would be moving into an increasingly hostile environment and should weaken significantly with time. Plan to update to remove PoPs from this evening, and reduce them overnight, restricting them to locations west of the Illinois River Valley. Otherwise, only minor tweaks are needed for the expected hourly trends. Bak && .AVIATION... ISSUED 1150 PM CDT Sat Apr 12 2014 The 06Z TAF forecast becomes rather tricky by late tonight across the central Illinois terminals. Southerly winds, frequently quite gusty, should prevail through the period ahead of a slowly approaching storm system. However, the forecast models continue to struggle with the details regarding when the precipitation threat arrives locally as the system draws closer. This also has a significant impact on how soon conditions fall below VFR. The low pressure center and frontal system with the storm still lie well west and north of central Illinois through thenight. While some of the guidance has precipitation chances arriving tonight as convective storm complex remnants to our northwest sink toward the area, confidence in this occurring is low. The better chance of showers and storms will come later Sunday morning into midday as the main system approaches the Illinois border from the west. Tried to time in arrival of the more widespread pre-frontal precipitation with the best model consensus, and carried no more than a VCSH mention before then. As the front draws closer heading into Sunday evening, showers/storms will become more widespread and heavier, resulting in the development of IFR conditions. Bak && .PREV DISCUSSION... ISSUED 215 PM CDT Sat Apr 12 2014 SHORT TERM...Tonight through Tuesday Warm weather to hold over our area through most of Sunday before a change to much colder weather on Monday. Main forecast concerns will be with timing of showers and thunderstorms into west central IL later this evening and over the remainder of the forecast area by Sunday night with light snow chances rearing its ugly head Monday evening as the last of the southern stream shortwaves pushes across the Ohio Valley. Warm front that raced through our area early this morning became active just after sunrise with severe storms across northern IL. That has effectively put a stop to the northward push of the boundary and that area from far northern IL west-southwest thru central Iowa will be the focus for additional thunderstorm development later this afternoon. Further south in our area, forecast soundings continue to show a capping inversion in place between 800-700 mb and short term forecast models suggest this will hold into the evening hours. So with any focusing mechanism remaining well to our north and the cap in place, POPs late this afternoon thru the mid evening hours will be low. Further west and north, with some impressive CAPE and shear values forecast across Iowa, supercells will likely be the initial storm mode before transitioning to more of quasi-linear system late this evening. Question becomes if it does become organized and a cold pool develops, we will see a shift southeast into our far northwest counties late this evening. This is supported by the SPC WRF and HRW-ARW and NMM simulations which quickly consolidates from any discrete storms in west central Iowa into a fairly decent line of storms before the cold pool becomes dominant and storms dissipate as they translate southeast into our area by midnight. Still the chance that if the storms remain rather un-organized and do not develop any cold pool, we may not see much if any rain across our north overnight as the storm movement will remain mostly east-northeast across Iowa into northern IL. Will continue to keep the highest POPs across the northwest for tonight with no precip expected east of I-55. It still appears we will be able to enjoy one more warm day on Sunday with our east and southeast counties probably rain free until Sunday night. The latest ECMWF and NAM-WRF eject a southern stream wave northeast into the Midwest by late in the day with an increase in shower and thunderstorm chances from west to east with the highest during the day mainly west of I55. Moisture transport really picks up ahead of this wave late in the day with precipitable water values of 1.25-1.40 inches, well above climatological norms for our area for the middle of April. All areas should see a decent rain event Sunday night as the surface wave slowly moves northeast along the boundary, which will be right across our forecast area Sunday night into Monday morning. Better Cape and Shear values will be south of our area with forecast soundings pretty much saturated from the ground up Sunday night, so the main threat will be with the threat for heavy rainfall as the heavier bands of rain with isolated storms move from southwest to northeast. Rainfall totals still look to be in the 1 to 2 inch range with some isolated higher amounts possible Sunday night into early Monday as the surface low enhanced the low level convergence along the slow moving frontal boundary. Much colder weather will slowly filter in on Monday as the wave shifts off to our northeast allowing the boundary to make a bit more progress to our east during the day. May have a tough time getting temps to budge out of the 40s north, with morning highs expected in the southeast before temps fall off in the afternoon. The NAM-WRF and to a certain extent the GFS model suggests additional energy to push across our area on Monday with temp profiles trending colder and more supportive of at least a rain/snow mixture by late afternoon, and especially after dark. However, the better lift looks to shift away from our area in the evening so precip amounts look to be very light, but cold enough to support a mix before the precip shuts down by midnight. With the slow moving 500 mb trof axis finally shifting off to our east late Monday night, skies should begin to clear as high pressure settles in bringing frost/freezing temperatures to most of our area by Tuesday morning with lows from the mid 20s far north to the lower 30s southeast. Quiet weather expected the remainder of the day on Tuesday as the fair weather system drifts across our area keeping it on the dry and chilly side. LONG TERM...Wednesday through Saturday Several weather systems to affect our area this period but moisture will be rather limited with the first wave pushing across the Great Lakes on Thursday. Next wave embedded in the zonal flow arrives on Saturday with a better supply of moisture ahead of it. As a result, will add some mentionable POPs into the grids for the start of the weekend. After the cool start on Wednesday, our upper flow flattens out enough to allow milder temperatures back into the area for the end of the week with temperatures closer to normal for the middle of April. Smith && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1251 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 702 PM CDT SAT APR 12 2014 EVENING SOUNDING SO FAR CONTINUES TO SHOW A CONSIDERABLE CAP IN PLACE WHICH IS PREVENTING CONVECTION FROM OCCURRING ACROSS THE IMMEDIATE AREA. SATELLITE/RADAR TRENDS THE PAST 3 HOURS SHOW NEW CONVECTION DEVELOPING WITH NEW STORMS DEVELOPING BACK TOWARD KOMA AND SOUTH TO KFNB. BASED ON RADAR TRENDS OVER THE PAST 40 MINUTES...A SEMI BROKEN LINE OF CONVECTION WILL BEGIN TO CONNECT THE SOUTHWEST IOWA CONVECTION WITH THE NORTHEAST IOWA CONVECTION. NOWCASTING TOOLS AND TRENDS FROM THE RAP INDICATE CONVECTION WILL JUST SKIRT OR CATCH THE EXTREME NORTHWEST PARTS OF THE AREA OVER THE NEXT 1-2 HOURS. STARTING AROUND 9-10 PM THERE SHOULD BE CONSIDERABLE UPSCALE GROWTH IN AREAL COVERAGE OF CONVECTION AS THE LLJ BEGINS TO STRENGTHEN. UPDATE ISSUED AT 437 PM CDT SAT APR 12 2014 BASED ON CLOUD/RADAR TRENDS AND WHAT IS BEING SUGGESTED INTERNALLY BY TRENDS FROM THE RAP ETC...A MAJORITY OF THE CURRENT CONVECTION SHOULD MOVE ALONG JUST NORTH OF THE AREA THROUGH 7 PM. ADDITIONAL CONVECTION SHOULD DEVELOP TO THE WEST OR WEST/SOUTHWEST ALONG THE BOUNDARY TOWARD KEBS. THERE ARE SUGGESTIONS OF NEW CONVECTIVE BOUNDARIES HELPING TO DEVELOP/PUSH CONVECTION VERY SLOWLY INTO THE HIGHWAY 20 CORRIDOR WEST OF KDBQ BETWEEN 5 AND 7 PM. AFTER 7 PM...IT WILL ONLY BE A MATTER OF TIME BEFORE CONVECTIVE BOUNDARIES AND THE MAIN SYNOPTIC BOUNDARY DEVELOP SCATTERED CONVECTION THAT BECOMES MORE NUMEROUS AS THE EVENING PROGRESSES. && .SYNOPSIS... ISSUED AT 302 PM CDT SAT APR 12 2014 A VERY PRONOUNCED FRONTAL BOUNDARY IS LOCATED FROM SIOUX CITY IOWA THROUGH FAR SOUTHWEST WISCONSIN AS OF 2 PM. THIS FRONT HAS BEEN THE FOCUS FOR ON ROUND OF SEVERE STORMS...AND WILL BE AGAIN THE FOCUS IN A FEW HOURS. THE MORNING ROUND OF SEVERE ELEVATED STORMS PRODUCED COPIOUS AMOUNTS OF LARGE HAIL...AS WELL AS A VERY STRONG PROGRESSIVE DOWN BURST WITH ONE SUPERCELL ALONG HIGHWAY 20 IN STEPHENSON COUNTY. THIS DOWN BURST MAY HAVE PRODUCED WINDS IN EXCESS OF 75 MPH. THE WARM SIDE OF THE BOUNDARY WHICH IS OVER THE ENTIRE CWA...IS WELL MIXED AND CONTINUES TO WARM. TEMPERATURES ARE NEAR 80 OVER ALL OF THE CWA...MAKING THIS EASILY THE WARMEST DAY IN MANY MONTHS. DEW POINTS IN THE MID TO UPPER 50S ARE ALREADY ESTABLISHED OVER THE MIDWEST...AND ANY FURTHER INCREASE WILL LIKELY OCCUR THROUGH CONVERGENCE PROCESSES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 302 PM CDT SAT APR 12 2014 TONIGHT WILL SEE STORMS FIRE INITIALLY IN NORTH CENTRAL IOWA TO NORTHEAST IOWA. DEEP LAYER SHEAR IS SUFFICIENT FOR SUPERCELLS...MUCH LIKE EARLIER TODAY. THIS PORTION OF THE EVENT SHOULD BE JUST NORTH OF THE CWA...BUT COULD IMPACT OUR FAR NORTHWEST THROUGH 7 PM. EITHER WAY...IT IS GOING TO BE CLOSE. BY LATER IN THE EVENING...A COLD POOL SHOULD BE WELL ESTABLISHED ALONG THE FRONT...ALLOWING STORMS TO PUSH EAST AND SOUTH AS A LINE OR BROKEN LINE. AT THAT TIME...THE THREAT SHOULD TRANSITION TO WIND...BEFORE THE LINE STALLS OR RUNS INTO A MORE STOUT CAP/EML STILL PRESENT IN THE WARM SECTOR. WHERE EVER THIS OCCURS...THE LINE SHOULD STALL OR AT LEAST SLOW FOR A POTENTIAL FOR REPEATING/TRAINING STORMS. THUS...THE HIGHEST PROBABILITY FOR SEVERE IS NORTHWEST...AS IS POPS...BUT IT LOOKS LIKE THE HIGHER PROBABILITY FOR TRAINING IS JUXTAPOSED TO THE SOUTHEAST...OVER OUR CENTRAL CWA FROM SOUTHWEST TO NORTHEAST. AS MESOSCALE PROCESSES EVOLVE...WE CAN GREATLY REFINE THIS DUAL THREAT. RAINS TONIGHT WILL BE SIGNIFICANT WITH OVER 1 INCH WHERE STORMS LAY OUT VERY LIKELY. SUNDAY...THE MAIN MOISTURE AND SYSTEM DYNAMICS ARRIVE IN THE MORNING...FOR ANOTHER CONVECTIVE ROUND OF THUNDERSTORMS. MUCH STRONGER UPPER DIFLUENCE IS FORECAST...BUT LESSER CAPE. THUS...EFFICIENT RAINFALL PROCESSES WITH HIGH PWAT VALUES SHOULD SUPPORT RAIN RATES OVER 0.5 PER HOUR AT TIMES. WITH STRONG FORCING ALL DAY...WE COULD SEE RAINFALL OF 1 TO 2 INCHES SUNDAY OVER THE WESTERN 2/3 OF THE CWA. IF WE WERE NOT IN DROUGHT...WITH UNFROZEN GROUND...THIS WOULD BE AN EASY FLASH FLOOD RISK...BUT THAT IS NOT THE CASE. WHILE WE MAY SEE SOME THREAT FOR FLASH FLOODING...AND RIVER FLOODING...IT DOES NOT LOOK WIDESPREAD ENOUGH TO WARRANT A WATCH GIVEN THE DRY ANTECEDENT CONDITIONS. ERVIN .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 302 PM CDT SAT APR 12 2014 THE MAIN FORCING ARRIVES SUNDAY EVENING SO WIDESPREAD RAIN WITH SOME EMBEDDED THUNDERSTORMS SHOULD BE SEEN. AFTER MIDNIGHT THE OVERALL FORCING BEGINS TO WEAKEN AS COLDER AIR STARTS GETTING PULLED INTO THE AREA. THE QUESTION AFTER MIDNIGHT IS HOW FAST DOES THE COLD AIR ARRIVE. BASED ON WHAT IS BEING SUGGESTED A MIX SHOULD DEVELOP PRIOR TO SUNRISE MONDAY OVER THE FAR NORTHWEST PARTS OF THE AREA. FOR THE FIRST FEW HOURS AFTER SUNRISE MONDAY THE MIX OF RAIN AND SNOW WILL MOVE SOUTHEAST WITH THE EXTREME NORTHWEST CHANGING OVER TO ALL SNOW. DUE TO THE WARMER GROUND ANY ACCUMULATIONS SHOULD BE A DUSTING AT BEST. AS MONDAY MORNING PROGRESSES...SOLAR INSOLATION WILL SLOWLY PUSH TEMPERATURES UP IN SPITE OF THE CLOUDS AND PRECIPITATION. BY LATE MORNING THE PRECIPITATION SHOULD CHANGE BACK TO ALL RAIN WITH RAIN ENDING FROM WEST TO EAST MONDAY AFTERNOON. TEMPERATURES WILL AVERAGE WELL BELOW NORMAL. LINGERING LIGHT RAIN WILL BE SEEN ACROSS THE FAR EAST EARLY MONDAY EVENING BEFORE ENDING. THE REMAINDER OF MONDAY NIGHT WILL BE DRY AND COLD AS CANADIAN HIGH PRESSURE BUILDS INTO THE MIDWEST. QUIET AND COOL CONDITIONS WILL BE SEEN ACROSS THE AREA ON TUESDAY AS THE HIGH REMAINS ACROSS THE MIDWEST. TEMPERATURES WILL CONTINUE TO AVERAGE WELL BELOW NORMAL. TUESDAY NIGHT ON... THE CURRENT MODEL CONSENSUS HAS DRY CONDITIONS TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH TEMPERATURES AVERAGING SLIGHTLY BELOW NORMAL. THURSDAY THROUGH SATURDAY THE MODEL CONSENSUS GOES FROM SLIGHT CHANCE POPS THURSDAY...TO CHANCE POPS THURSDAY NIGHT THROUGH SATURDAY. THERE IS LOOSE AGREEMENT THAT ANOTHER SLOW MOVING STORM SYSTEM WILL AFFECT THE MIDWEST IN THE THURSDAY THROUGH SATURDAY TIME FRAME. HOWEVER...THERE ARE DIFFERENCES BETWEEN THE MODELS AS TO HOW THE STORM SYSTEM WILL EVOLVE AND WHERE IT TRACKS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1241 AM CDT SUN APR 13 2014 MCS CURRENTLY WORKING ACROSS THE AREA IS GENERATING AREAS OF 40-50 MPH WINDS FOR BRIEF PERIODS ALONG WITH MOSTLY MVFR CONDITIONS. THIS SYSTEM SHOULD EXIT THE AREA DURING THE NEXT FEW HOURS... LEAVING A BRIEF RESPITE UNTIL THE NEXT ROUND OF RAIN MOVES IN LATER THIS MORNING. LOOKS LIKE WIDESPREAD MVFR/IFR CONDITIONS WILL DEVELOP LATER THIS MORNING AS RAIN REDEVELOPS OVER THE AREA. THE BROAD AREA OF RAIN WILL BE INTERSPERSED WITH SCATTERED THUNDERSTORMS. BUT GIVEN THE DURATION OF RAIN TODAY AND THE LOW CHANCE OF THUNDER AT ANY ONE LOCATION AT ANY ONE TIME...HAVE LEFT IT OUT OF THE FORECAST AT THIS POINT. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...ERVIN SHORT TERM...ERVIN LONG TERM...08 AVIATION...WOLF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
505 PM MDT MON APR 14 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1252 PM MDT MON APR 14 2014 EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT. ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE CWA. ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND W-SW WINDS DEVELOP LATE TONIGHT. MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA. SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH. MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP (ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH AT THIS TIME. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 237 PM MDT MON APR 14 2014 MODEL SOLUTIONS REMAIN IN CLOSE AGREEMENT THROUGH THE END OF THE WORK WEEK AND THEN BEGIN TO DIVERGE THROUGH THE WEEKEND AS AN UPPER TROUGH MOVES ACROSS THE NORTHERN PLAINS IN THE NORTHERN BRANCH OF THE UPPER FLOW AND A SHORT WAVE TROUGH EMBEDDED IN THE SOUTHERLY BRANCH TRIES TO COME INTO PHASE WITH THE NORTHERLY BRANCH. THE GFS REMAINS THE MORE PROGRESSIVE SOLUTION WHILE THE ECMWF LAGS BEHIND NEARLY 24 HOURS. THIS IS PROVING TO BE TROUBLESOME WITH THE TIMING OF THE PRECIPITATION THAT IS POSSIBLE BETWEEN A LATE FRIDAY TO LATE SATURDAY TIME FRAME. HAVE GONE WITH SOME KIND OF BLENDED COMPROMISE SOLUTION FOR THE FRIDAY THROUGH SUNDAY TIME PERIOD WITH RAIN SHOWERS TRANSITIONING TO A FEW THUNDERSTORMS AND BACK TO RAIN SHOWERS ON SATURDAY AND SATURDAY NIGHT. EXPECT DRY AND WARMER CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND INTO THE BEGINNING OF NEXT WEEK AS A LARGE RIDGE AMPLIFIES OVER THE WESTERN UNITED STATES AND MOVES EAST OVER THE ROCKIES AND HIGH PLAINS REGION. BACKTRACKING TO THE MID-WEEK SYSTEM... EXPECT RAIN TO DEVELOP EAST OF THE ROCKIES LATE WEDNESDAY AND TRANSITION TO SNOW AS IT SPREADS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. EXPECT A TRANSITION BACK TO RAIN DURING THE DAY ON THURSDAY...BUT MAY END UP STAYING MORE SNOW THROUGH THURSDAY MORNING IF TEMPERATURES REMAIN COLDER AND WET BULB ZERO TEMPERATURES ARE COLDER AS THEY WERE WITH THE LAST SYSTEM THAT DEPOSITED SNOW ACROSS THE FORECAST AREA. EXPECT PRECIPITATION TO END FROM WEST TO EAST ACROSS THE FORECAST AREA LATE IN THE DAY ON THURSDAY. TEMPS WILL WARM BRIEFLY ON FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 500 PM MDT MON APR 14 2014 KGLD...VFR CONDITIONS THROUGH THE PERIOD. GUSTY NORTHWEST WINDS AT TAF ISSUANCE WILL QUICKLY SUBSIDE TO AROUND 06KTS BETWEEN 01Z-02Z WHILE BACKING TO THE WEST. AROUND 09Z SOUTHWEST WINDS AROUND 15KTS EXPECTED AND WITH THE ADDITION OF SUNSHINE TUESDAY LATE MORNING THROUGH THE REST OF THE DAY GUSTS OF 25-30KTS EXPECTED. KMCK...VFR CONDITIONS THROUGH THE PERIOD. GUSTY NORTHWEST WINDS AT TAF ISSUANCE WILL QUICKLY SUBSIDE BETWEEN 01Z-02Z TO 10KTS FROM THE WEST. LIGHT SOUTHWEST WINDS EXPECTED BY 09Z BUT AN INCREASE EXPECTED AFTER 16Z WITH SUSTAINED SPEEDS AROUND 15KTS WITH GUSTS AROUND 25KTS THROUGH THE REST OF THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...LOCKHART AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
401 PM MDT SUN APR 13 2014 .SHORT TERM...(THIS AFTERNOON THROUGH MONDAY) ISSUED AT 203 PM MDT SUN APR 13 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7 CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN COLORADO. REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE ADVISORY BEFORE 00Z. REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN THE FAR SOUTH. REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z. LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS THE CWA. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 210 PM MDT SUN APR 13 2014 A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM. MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1149 AM MDT SUN APR 13 2014 AT KMCK...VLIFR CONDITIONS ARE OCCURRING CURRENTLY BECAUSE OF ONE QUARTER MILE VISIBILITY FROM SNOW. RADAR TRENDS AND UPSTREAM OBS SUGGEST THIS WILL LIKELY PERSIST FOR A COUPLE MORE HOURS BEFORE SNOW INTENSITY LESSENS AND CONDITIONS IMPROVE TO IFR. LIGHT SNOW AND IFR CEILINGS WILL PERSIST INTO THE EVENING WITH A GRADUAL IMPROVEMENT EXPECTED. IN THE 03-06Z PERIOD...VFR CONDITIONS SHOULD RETURN. AT KGLD...THE HEAVIEST SNOWFALL AND MOST SIGNIFICANT VISIBILITY REDUCTIONS SHOULD OCCUR THROUGH ABOUT 20-21Z WITH A BAND OF SNOW MOVING EASTWARD ACROSS THE TERMINAL. RADAR TRENDS AND UPSTREAM OBSERVATIONS WERE USED FOR TIMING THE IFR AND POSSIBLY BRIEFLY NEAR LIFR CONDITIONS TRANSITIONING TO MVFR LATER THIS EVENING. IN THE 04-07Z PERIOD...CONDITIONS WILL LIKELY RETURN TO VFR. FOR BOTH TERMINALS...NORTH WINDS WILL PERSIST AND COULD GUST TO 35 KTS THROUGH THE AFTERNOON. THE GUSTS WILL SUBSIDE AND WINDS WILL GRADUALLY VEER SLIGHTLY TO A MORE NORTH-NORTHWESTERLY DIRECTION OVERNIGHT...BUT 12-20 KT WINDS WILL CONTINUE THROUGH THE END OF THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT FOR KSZ001>004-013. WIND ADVISORY UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR KSZ014>016-027>029-041-042. CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ090>092. NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT FOR NEZ079>081. && $$ SHORT TERM...DR LONG TERM...LOCKHART AVIATION...BRB
AREA FORECAST DISCUSSION
NWS TOPEKA KS
355 PM CDT Sun Apr 13 2014 .SHORT TERM...(This Evening through Monday) Issued at 326 PM CDT SUN APR 13 2014 20Z water vapor imagery shows a shortwave lifting across eastern KS as another wave digs south towards the four corners region. This initial wave has sparked a line of thunderstorms to form along a cold front that is surging southeast through the forecast area. Much of the short range guidance is pointing towards the convection to be east of the forecast area by 7 pm, which fits in with current radar trends. Therefore have lowered pops for this evening and removed mention of thunder. There is a band of snow across NEB. The HRRR and RAP suggest the tail end of this precip may move east along the NEB state line through the evening as the first shortwave lifts northeast. Precip accumulations with this should be fairly light as the better mid level frontogenesis stays mainly to the north. However as the second shortwave comes out of the Rockies late tonight and through the morning Monday, this frontogenetical band redevelops south and most guidance is pointing at a band of snow moving over east central KS. The frontogenesis looks strong enough for a decent band of snow and possible accumulations around an inch through late morning Monday. This will be highly dependent on the intensity of the snowfall however since ground temps remain relatively warm. If the band produces higher snowfall rates, some parts of east central KS could see accumulations a little higher. In between the convection this afternoon and the frontogenetical precip overnight, think there will be a lull in the precip and have tapered pops down this evening. Models show saturation in the lower levels hinting at the possibility for some drizzle which could be freezing depending on surface temps. However the conditions for drizzle do not look to persist for long as some mid level drying occurs before the next shortwave moves in and saturates the column. Overall am not to excited about the prospects for drizzle but can`t rule out the chance so will include a mention in the forecast. Lows tonight should fall into the lower 30s due to strong cold air advection behind the front. Temps in central NEB have already fallen into the upper 20s suggesting my lows may not be cool enough. In any case, freezing temps look likely tonight and will issue as freeze warning as we have entered the locally defined growing season. Cold air advection persists through the morning Monday so highs are not expected to warm much. However think clouds will eventually clear out by the afternoon so some insolation may help to warm highs into the 40s. .LONG TERM...(Monday Night through Sunday) Issued at 326 PM CDT SUN APR 13 2014 Monday night through Wednesday looks dry as the central plains see dry northwest flow develop ahead of the next wave expected to dig into the plains by Thursday. The medium range models seem to be in some agreement with timing of the next wave therefore have trended pops up for Thursday and Thursday night. There does not appear to be much instability with this system as warm moist are is slow to return. However there does appear to be another shot of cold air moving in Thursday night which could cause a brief change over to snow before the precip comes to an end. Therefore have maintained a mention of rain and snow for Thursday night. While less certain, there are indications of a southern stream wave trying to phase with a northern stream wave over the area Sunday. Confidence is low since the GFS struggles to advect moisture this far north. However with the ECMWF breaking out some QPF, will insert some low (20-30%) POPs Saturday night and Sunday. A hard freeze looks likely Tuesday morning as skies clear out and surface ridging moves over the region. Therefore have continued with lows in the lower to middle 20s and will post a freeze warning through Tuesday morning too. Southerly flow returns for Wednesday helping to moderate the cool temps before the next cold front moves in Thursday and knocks temps back down into the 40s and 50s for Thursday and Friday. With a split flow for the weekend and the northern stream remaining north, temps should moderate into the 60s for the weekend. && .AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon) Issued at 1237 PM CDT SUN APR 13 2014 Limiting conditions should dominate the forecast with cold front passing MHK recently and then TOP and FOE around 20Z. TSRA ongoing and should persist for a few hours with instability waning with time. Higher confidence in IFR cigs versus precipitation in the bulk of the forecast. Will go ahead with -SN inclusion given for a few hours given model trends. VFR should return by the end of this forecast. && .TOP WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING from Midnight tonight to 10 AM CDT Monday FOR KSZ008>012-020>024-026-034>040-054>056-058-059. FREEZE WARNING from 11 PM Monday to 9 AM CDT Tuesday FOR KSZ008>012-020>024-026-034>040-054>056-058-059. WIND ADVISORY until 9 PM CDT this evening FOR KSZ008>010-020-021- 034. && $$ SHORT TERM...Wolters LONG TERM...Wolters AVIATION...65
AREA FORECAST DISCUSSION
NWS GOODLAND KS
204 PM MDT SUN APR 13 2014 .SHORT TERM...(THIS AFTERNOON THROUGH MONDAY) ISSUED AT 203 PM MDT SUN APR 13 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7 CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN COLORADO. REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE ADVISORY BEFORE 00Z. REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN THE FAR SOUTH. REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z. LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS THE CWA. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 152 AM MDT SUN APR 13 2014 SHORTWAVE TROUGH DROPPING OUT OF THE NORTHERN ROCKIES WILL BEGIN TO APPROACH ON WEDNESDAY. ASSOCIATED SURFACE COLD FRONT WILL BE MOVING INTO THE AREA BY WEDNESDAY AFTERNOON...SO WILL HAVE COOLER TEMPERATURES NORTHWEST. COLD FRONT WILL CLEAR THE AREA BY WEDNESDAY NIGHT AND AS LIFT INCREASES WITH SHORTWAVE TROUGH WILL HAVE A CHANCE FOR SNOW NORTHWEST AND RAIN AND SNOW ELSEWHERE THROUGH THURSDAY. THIS EVENT LOOKS VERY SIMILAR TO THE ONE OCCURRING TODAY ACROSS THE AREA AND COULD BRING ANOTHER FEW INCHES OF SNOW...ALTHOUGH GFS FORECAST OF UP TO A FOOT LOOKS OVERDONE. DROPPED TEMPERATURES ON THURSDAY AS MUCH AS ISC ALLOWED...BUT WITH CLOUDS/UPSLOPE/PRECIPITATION NOT EXPECTING MUCH WARMING. SHORTWAVE RIDGING REBUILDS ON FRIDAY WITH DRY CONDITIONS AND TEMPERATURES REBOUNDING TO SLIGHTLY BELOW NORMAL. SOUTHERN STREAM SYSTEM ON SATURDAY LOOKS RATHER WEAK AT THIS TIME AND MAY BE TOO FAR SOUTH...SO WILL KEEP IT DRY WITH TEMPERATURES SLIGHTLY ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1149 AM MDT SUN APR 13 2014 AT KMCK...VLIFR CONDITIONS ARE OCCURRING CURRENTLY BECAUSE OF ONE QUARTER MILE VISIBILITY FROM SNOW. RADAR TRENDS AND UPSTREAM OBS SUGGEST THIS WILL LIKELY PERSIST FOR A COUPLE MORE HOURS BEFORE SNOW INTENSITY LESSENS AND CONDITIONS IMPROVE TO IFR. LIGHT SNOW AND IFR CEILINGS WILL PERSIST INTO THE EVENING WITH A GRADUAL IMPROVEMENT EXPECTED. IN THE 03-06Z PERIOD...VFR CONDITIONS SHOULD RETURN. AT KGLD...THE HEAVIEST SNOWFALL AND MOST SIGNIFICANT VISIBILITY REDUCTIONS SHOULD OCCUR THROUGH ABOUT 20-21Z WITH A BAND OF SNOW MOVING EASTWARD ACROSS THE TERMINAL. RADAR TRENDS AND UPSTREAM OBSERVATIONS WERE USED FOR TIMING THE IFR AND POSSIBLY BRIEFLY NEAR LIFR CONDITIONS TRANSITIONING TO MVFR LATER THIS EVENING. IN THE 04-07Z PERIOD...CONDITIONS WILL LIKELY RETURN TO VFR. FOR BOTH TERMINALS...NORTH WINDS WILL PERSIST AND COULD GUST TO 35 KTS THROUGH THE AFTERNOON. THE GUSTS WILL SUBSIDE AND WINDS WILL GRADUALLY VEER SLIGHTLY TO A MORE NORTH-NORTHWESTERLY DIRECTION OVERNIGHT...BUT 12-20 KT WINDS WILL CONTINUE THROUGH THE END OF THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT FOR KSZ001>004-013. WIND ADVISORY UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR KSZ014>016-027>029-041-042. CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ090>092. NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT FOR NEZ079>081. && $$ SHORT TERM...DR LONG TERM...024 AVIATION...BRB
AREA FORECAST DISCUSSION
NWS WICHITA KS
1240 PM CDT SUN APR 13 2014 ...UPDATED FOR 18Z AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 347 AM CDT SUN APR 13 2014 THE MAIN STORM SYSTEM IS STILL SITTING OFF OVER THE FOUR CORNER REGION WITH AN ARM OF THE PV ANOMALY EXTENDING ACROSS KANSAS. THIS ARM HELPED TO FIRE THE ACTIVITY ON THE FRONT SATURDAY EVENING. MOISTURE TRANSPORT THIS MORNING IN AN ABUNDANTLY RICH AIRMASS HAS CAUSED THUNDERSTORMS TO DEVELOP OVER SOUTHEAST KANSAS. THE FRONT BISECTS THE FORECAST AREA FROM SALINA SOUTHWEST TO SOUTH OF GREAT BEND. THIS FRONT WILL BE THE FOCUS FOR WEATHER TODAY. BILLINGS WRIGHT && .UPDATE... ISSUED AT 1127 AM CDT SUN APR 13 2014 STILL LOOKING LIKE SCATTERED STRONG/SEVERE STORMS ARE A GOOD BET THIS AFTERNOON...MAINLY AS EARLY AS 1-2PM...GENERALLY ALONG/EAST OF A LINE EXTENDING FROM WELLINGTON TO WICHITA TO HILLSBORO...AS A STRONG COLD FRONT BLASTS SOUTHEAST. CURRENT CLOUDS ARE INHIBITING STRONG SURFACE HEATING AND ASSOCIATED SFC-BASED INSTABILITY...BUT STEEP MID-LEVEL LAPSE RATES AND SOME HEATING WILL LIKELY CONTRIBUTE UP TO 2000 J/KG OF MLCAPE BY PEAK HEATING AHEAD OF THE FRONT. CLOCKWISE TURNING HODOGRAPHS SUGGESTS UPDRAFT ROTATION IS LIKELY...ESPECIALLY AT THE ONSET OF CONVECTIVE INITIATION. THIS WILL SUPPORT LARGE HAIL (GOLFBALL-TENNIS BALL SIZE)...ALTHOUGH LACK OF STRONG MID-LEVEL FLOW AND ASSOCIATED 700-500MB SHEAR SHOULD PREVENT GIANT HAIL FROM OCCURRING. ACTIVITY SHOULD TEND TO GO LINEAR FAIRLY QUICKLY GIVEN STRONG FRONTAL FORCING...DEEP LAYER SHEAR LARGELY ORIENTED PARALLEL TO BOUNDARY...AND FLOW ALOFT TENDING TO BACK WITH HEIGHT. ONCE CONVECTION GOES LINEAR...HAIL SIZE WILL TEND TO DECREASE...WITH QUARTER-GOLFBALL SIZE HAIL AND 60-70 MPH WINDS POSSIBLE. THINKING ALL ACTIVITY WILL EXIT SOUTHEAST KS BETWEEN 7-9 PM. FURTHERMORE...CANNOT RULE OUT AN ISOLATED TORNADO...ESPECIALLY INITIALLY THIS AFTERNOON...BUT TORNADO THREAT SHOULD DECREASE ONCE ACTIVITY BEGINS TO MERGE AND GO LINEAR. ADK && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 THIS PERIOD REMAINS VERY ACTIVE WITH A VARIETY OF WEATHER TYPES TO BRING HAZARDOUS WEATHER TO THE AREA. WILL BREAK THIS SECTION UP BASED ON TYPE OF HAZARDOUS WEATHER VS. A NARRATIVE. SEVERE WEATHER POTENTIAL: THE SEVERE WEATHER THREAT HAS BEEN WELL FORECASTED THE PAST FEW DAYS AND LITTLE HAS CHANGED REGARDING THE MAIN CONCERN. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AS IT ADVANCES SOUTHEASTWARD ACROSS THE AREA THIS AFTERNOON. THE LATEST 5Z HRRR SHOWS THUNDERSTORMS UNZIPPING ALONG THE FRONT AROUND 18-20Z JUST EAST OF WICHITA...ALONG THE KANSAS TURNPIKE. THINK AREAS ALONG AND EAST OF WICHITA WILL HAVE THE BEST CHANCE FOR THUNDERSTORMS IN AN UNSTABLE ATMOSPHERE. TEMPERATURES WILL SOAR THIS AFTERNOON AND WITH 60+ DEWPOINTS...CAPES WILL BE BETWEEN 1500-2500 J/KG. THE CAPE COMBINED WITH ADEQUATE BULK SHEAR WILL FOSTER SEVERE STORM GROWTH WITH LARGE DAMAGING HAIL THE PRIMARY THREAT. HAIL GREATER THAN THE SIZE OF GOLF BALLS AND UP TO BASEBALLS WILL BE POSSIBLE. WIND POTENTIAL: STRONG GUSTY NORTH WINDS WILL ACCOMPANY THE COLD FRONT THIS AFTERNOON. A TIGHT PRESSURE GRADIENT WILL HELP WINDS EXCEED 30 MPH WITH GUSTS UP TO 40-45 MPH. A WIND ADVISORY WAS INHERITED AND WE EXPANDED IT FURTHER EAST AND SOUTH TO COINCIDE WITH GREATEST PERCEIVED THREAT. ALSO EXTENDED THE WIND ADVISORY IN TIME TO 02Z AS THE PRESSURE GRADIENT WILL NOT LET UP UNTIL CLOSE TO MORNING. CONFIDENCE ON STRONGER WINDS PERSISTING PAST 02Z IS NOT HIGH...BUT IF THEY DO COULD SEE ADVISORY EXTENDED IN TIME. SNOW POTENTIAL: THE GUIDANCE CONTINUES TO BE TREND COLDER WITH THE AIRMASS THAT IS FOLLOWING TODAY`S COLD FRONT. THE VERTICAL COLUMN COOLS ENOUGH SUCH THAT SNOW IS GOING TO BE POSSIBLE WITH SOME LIGHT ACCUMULATIONS POSSIBLE. SOUNDINGS SHOW A PROFILE COMPLETELY BELOW ZERO FOR MUCH OF THE FORECAST AREA AS THE COLDER AIR PUSHES SOUTHEAST...THUS SNOW WILL DEVELOP DURING THE OVERNIGHT HOURS AND TRANSITION SOUTHEASTWARD. THE LATEST NAM SHOWS ACCUMULATIONS OF UPWARDS OF 2-3 INCHES...BUT CONFIDENCE ON THOSE AMOUNTS OCCURRING IS LOW. DO THINK THERE COULD BE SOME ACCUMULATIONS IN CENTRAL KANSAS...MAINLY ON GRASSY SURFACES...BUT ALSO ON THE ROADWAYS IF THE RATE IS HIGH ENOUGH. HOWEVER...ANY ACCUMULATION THAT DOES OCCUR WILL NOT LAST VERY LONG...AS WARM SURFACE TEMPERATURES WILL CAUSE IT TO MELT QUICKLY. FREEZE POTENTIAL: THE COLD AIR WILL MOVE INTO THE REGION TONIGHT...AND DOMINATE MONDAY NIGHT/TUESDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR CENTRAL KANSAS FOR TONIGHT/MONDAY MORNING FOR TEMPERATURES THAT WILL DROP BELOW 30 DEGREES. DESPITE THE STRONGER WINDS...COLD TEMPS WILL BE A CONCERN FOR SENSITIVE VEGETATION. CONFIDENCE IN THIS IS MEDIUM AND WENT THE WATCH ROUTE TO ALLOW LATER SHIFTS TO ADJUST IF NEEDED. THE BIGGEST CONCERN...HOWEVER...IS FOR MONDAY NIGHT/TUESDAY MORNING AS WIDESPREAD TEMPS BETWEEN 20-25 DEGREES ARE EXPECTED. HAVE A FREEZE WATCH FOR THE WHOLE AREA AND CONFIDENCE IS VERY HIGH THAT THIS WILL OCCUR. TAKE PRECAUTIONS TO COVER ANY SENSITIVE VEGETATION. TEMPERATURES: TEMPERATURES WILL BE HIGH TODAY AHEAD OF THE FRONT WITH A NON- DIURNAL CURVE. HOWEVER...THE COLD AIRMASS...CLOUDS AND PRECIPITATION POSSIBILITIES WILL KEEP TEMPS COLD ON MONDAY. CURRENTLY THINK HIGHS WILL STRUGGLE TO GET OUT OF THE 40S AND MAY STRUGGLE TO GET OUT OF THE LOW 40S. IF THIS HAPPENS...RECORD COOL HIGHS MAY BE BROKEN FOR MONDAY...SEE CLIMATE SECTION FOR MORE INFORMATION. BILLINGS WRIGHT .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 ZONAL FLOW WILL QUICKLY RETURN TO THE UPPER AIR PATTERN...WITH BREEZY SOUTH WINDS ACROSS EASTERN KANSAS ON WEDNESDAY. THE NEXT UPPER DISTURBANCE WILL APPROACH FOR THURSDAY DRAGGING A FRONT INTO THE AREA. THIS WILL BE THE NEXT CHANCE FOR PRECIPITATION AND ANOTHER COOLER AIRMASS. HAVE DROPPED MAX TEMPS FOR THURSDAY. LITTLE IN THE WAY OF INSTABILITY...SO THINK THE PRECIPITATION WILL MAINLY BE IN THE FORM OF RAIN. THIS SYSTEM WILL EXIT ON FRIDAY...AND TEMPS WILL WARM INTO THE WEEKEND TO NEAR NORMAL. BILLINGS WRIGHT && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1239 PM CDT SUN APR 13 2014 ANTICIPATE NUMEROUS SHOWERS/THUNDERSTORMS GENERALLY EAST OF I-135 THIS AFTERNOON...AS A STRONG COLD FRONT BLASTS SOUTHEAST ACROSS THE REGION. STRONGEST ACTIVITY WILL BE CAPABLE OF LARGE HAIL AND STRONG/SEVERE ERRATIC WINDS. FRONT AND ASSOCIATED THUNDERSTORMS SHOULD EXIT SOUTHEAST KS AROUND 00Z. IN WAKE OF THE FRONT...VERY STRONG NORTHWEST WINDS WILL SPREAD SOUTHEAST...ALONG WITH HIGH IFR TO LOW MVFR CIGS. AS MAIN UPPER SYSTEM PULLS OUT OVERNIGHT...SHOULD EVEN SEE AREAS OF LIGHT SNOW DEVELOP FROM WEST TO EAST LATER TONIGHT INTO MONDAY MORNING...WITH LIGHT ACCUMULATIONS POSSIBLE ACROSS A GOOD CHUNK OF THE AREA. ADK && .FIRE WEATHER... ISSUED AT 347 AM CDT SUN APR 13 2014 GRASSLAND FIRE DANGER IS VERY HIGH THIS AFTERNOON AND MONDAY AFTERNOON ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. THE MOST CONCERNING PERIOD IS THAT BEFORE THUNDERSTORMS DEVELOP. AFTER THAT TIME...THE FIRE DANGER WILL DIMINISH. THE DRY AIR AIRMASS WILL CAUSE EXTREME FIRE DANGER TO BE A CONCERN TUESDAY AND WEDNESDAY WITH BREEZY SOUTH WINDS AND CURED FUELS. BILLINGS WRIGHT && .CLIMATE... ISSUED AT 347 AM CDT SUN APR 13 2014 RECORD COOL HIGHS ARE POSSIBLE ON MONDAY APRIL 14TH, 2014 COOLEST HIGH RECORDS WICHITA....45 DEGREES IN 1928 CHANUTE....47 DEGREES IN 1983 RUSSELL....44 DEGREES IN 1993 SALINA.....44 DEGREES IN 1993 BILLINGS WRIGHT && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 80 34 43 24 / 40 40 50 0 HUTCHINSON 71 31 44 24 / 40 60 30 0 NEWTON 77 31 42 24 / 40 40 40 0 ELDORADO 78 33 42 25 / 60 40 50 0 WINFIELD-KWLD 82 36 44 25 / 60 40 40 0 RUSSELL 55 29 46 23 / 60 60 10 0 GREAT BEND 56 28 46 22 / 60 60 20 0 SALINA 66 31 46 23 / 50 60 20 0 MCPHERSON 70 30 44 24 / 50 60 20 0 COFFEYVILLE 79 38 45 26 / 80 50 50 0 CHANUTE 78 36 44 24 / 80 40 50 0 IOLA 75 36 43 24 / 80 40 50 0 PARSONS-KPPF 79 37 45 24 / 80 50 50 0 && .ICT WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR KSZ032-033-047>053-067>072-082-083-091>096-098>100. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ032-033-047>052- 067-068-082-083-091-092. FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR KSZ032- 033-047>051. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1127 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 1127 AM CDT SUN APR 13 2014 STILL LOOKING LIKE SCATTERED STRONG/SEVERE STORMS ARE A GOOD BET THIS AFTERNOON...MAINLY AS EARLY AS 1-2PM...GENERALLY ALONG/EAST OF A LINE EXTENDING FROM WELLINGTON TO WICHITA TO HILLSBORO...AS A STRONG COLD FRONT BLASTS SOUTHEAST. CURRENT CLOUDS ARE INHIBITING STRONG SURFACE HEATING AND ASSOCIATED SFC-BASED INSTABILITY...BUT STEEP MID-LEVEL LAPSE RATES AND SOME HEATING WILL LIKELY CONTRIBUTE UP TO 2000 J/KG OF MLCAPE BY PEAK HEATING AHEAD OF THE FRONT. CLOCKWISE TURNING HODOGRAPHS SUGGESTS UPDRAFT ROTATION IS LIKELY...ESPECIALLY AT THE ONSET OF CONVECTIVE INITIATION. THIS WILL SUPPORT LARGE HAIL (GOLFBALL-TENNIS BALL SIZE)...ALTHOUGH LACK OF STRONG MID-LEVEL FLOW AND ASSOCIATED 700-500MB SHEAR SHOULD PREVENT GIANT HAIL FROM OCCURRING. ACTIVITY SHOULD TEND TO GO LINEAR FAIRLY QUICKLY GIVEN STRONG FRONTAL FORCING...DEEP LAYER SHEAR LARGELY ORIENTED PARALLEL TO BOUNDARY...AND FLOW ALOFT TENDING TO BACK WITH HEIGHT. ONCE CONVECTION GOES LINEAR...HAIL SIZE WILL TEND TO DECREASE...WITH QUARTER-GOLFBALL SIZE HAIL AND 60-70 MPH WINDS POSSIBLE. THINKING ALL ACTIVITY WILL EXIT SOUTHEAST KS BETWEEN 7-9 PM. FURTHERMORE...CANNOT RULE OUT AN ISOLATED TORNADO...ESPECIALLY INITIALLY THIS AFTERNOON...BUT TORNADO THREAT SHOULD DECREASE ONCE ACTIVITY BEGINS TO MERGE AND GO LINEAR. ADK && .SYNOPSIS... ISSUED AT 347 AM CDT SUN APR 13 2014 THE MAIN STORM SYSTEM IS STILL SITTING OFF OVER THE FOUR CORNER REGION WITH AN ARM OF THE PV ANOMALY EXTENDING ACROSS KANSAS. THIS ARM HELPED TO FIRE THE ACTIVITY ON THE FRONT SATURDAY EVENING. MOISTURE TRANSPORT THIS MORNING IN AN ABUNDANTLY RICH AIRMASS HAS CAUSED THUNDERSTORMS TO DEVELOP OVER SOUTHEAST KANSAS. THE FRONT BISECTS THE FORECAST AREA FROM SALINA SOUTHWEST TO SOUTH OF GREAT BEND. THIS FRONT WILL BE THE FOCUS FOR WEATHER TODAY. BILLINGS WRIGHT && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 THIS PERIOD REMAINS VERY ACTIVE WITH A VARIETY OF WEATHER TYPES TO BRING HAZARDOUS WEATHER TO THE AREA. WILL BREAK THIS SECTION UP BASED ON TYPE OF HAZARDOUS WEATHER VS. A NARRATIVE. SEVERE WEATHER POTENTIAL: THE SEVERE WEATHER THREAT HAS BEEN WELL FORECASTED THE PAST FEW DAYS AND LITTLE HAS CHANGED REGARDING THE MAIN CONCERN. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AS IT ADVANCES SOUTHEASTWARD ACROSS THE AREA THIS AFTERNOON. THE LATEST 5Z HRRR SHOWS THUNDERSTORMS UNZIPPING ALONG THE FRONT AROUND 18-20Z JUST EAST OF WICHITA...ALONG THE KANSAS TURNPIKE. THINK AREAS ALONG AND EAST OF WICHITA WILL HAVE THE BEST CHANCE FOR THUNDERSTORMS IN AN UNSTABLE ATMOSPHERE. TEMPERATURES WILL SOAR THIS AFTERNOON AND WITH 60+ DEWPOINTS...CAPES WILL BE BETWEEN 1500-2500 J/KG. THE CAPE COMBINED WITH ADEQUATE BULK SHEAR WILL FOSTER SEVERE STORM GROWTH WITH LARGE DAMAGING HAIL THE PRIMARY THREAT. HAIL GREATER THAN THE SIZE OF GOLF BALLS AND UP TO BASEBALLS WILL BE POSSIBLE. WIND POTENTIAL: STRONG GUSTY NORTH WINDS WILL ACCOMPANY THE COLD FRONT THIS AFTERNOON. A TIGHT PRESSURE GRADIENT WILL HELP WINDS EXCEED 30 MPH WITH GUSTS UP TO 40-45 MPH. A WIND ADVISORY WAS INHERITED AND WE EXPANDED IT FURTHER EAST AND SOUTH TO COINCIDE WITH GREATEST PERCEIVED THREAT. ALSO EXTENDED THE WIND ADVISORY IN TIME TO 02Z AS THE PRESSURE GRADIENT WILL NOT LET UP UNTIL CLOSE TO MORNING. CONFIDENCE ON STRONGER WINDS PERSISTING PAST 02Z IS NOT HIGH...BUT IF THEY DO COULD SEE ADVISORY EXTENDED IN TIME. SNOW POTENTIAL: THE GUIDANCE CONTINUES TO BE TREND COLDER WITH THE AIRMASS THAT IS FOLLOWING TODAY`S COLD FRONT. THE VERTICAL COLUMN COOLS ENOUGH SUCH THAT SNOW IS GOING TO BE POSSIBLE WITH SOME LIGHT ACCUMULATIONS POSSIBLE. SOUNDINGS SHOW A PROFILE COMPLETELY BELOW ZERO FOR MUCH OF THE FORECAST AREA AS THE COLDER AIR PUSHES SOUTHEAST...THUS SNOW WILL DEVELOP DURING THE OVERNIGHT HOURS AND TRANSITION SOUTHEASTWARD. THE LATEST NAM SHOWS ACCUMULATIONS OF UPWARDS OF 2-3 INCHES...BUT CONFIDENCE ON THOSE AMOUNTS OCCURRING IS LOW. DO THINK THERE COULD BE SOME ACCUMULATIONS IN CENTRAL KANSAS...MAINLY ON GRASSY SURFACES...BUT ALSO ON THE ROADWAYS IF THE RATE IS HIGH ENOUGH. HOWEVER...ANY ACCUMULATION THAT DOES OCCUR WILL NOT LAST VERY LONG...AS WARM SURFACE TEMPERATURES WILL CAUSE IT TO MELT QUICKLY. FREEZE POTENTIAL: THE COLD AIR WILL MOVE INTO THE REGION TONIGHT...AND DOMINATE MONDAY NIGHT/TUESDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR CENTRAL KANSAS FOR TONIGHT/MONDAY MORNING FOR TEMPERATURES THAT WILL DROP BELOW 30 DEGREES. DESPITE THE STRONGER WINDS...COLD TEMPS WILL BE A CONCERN FOR SENSITIVE VEGETATION. CONFIDENCE IN THIS IS MEDIUM AND WENT THE WATCH ROUTE TO ALLOW LATER SHIFTS TO ADJUST IF NEEDED. THE BIGGEST CONCERN...HOWEVER...IS FOR MONDAY NIGHT/TUESDAY MORNING AS WIDESPREAD TEMPS BETWEEN 20-25 DEGREES ARE EXPECTED. HAVE A FREEZE WATCH FOR THE WHOLE AREA AND CONFIDENCE IS VERY HIGH THAT THIS WILL OCCUR. TAKE PRECAUTIONS TO COVER ANY SENSITIVE VEGETATION. TEMPERATURES: TEMPERATURES WILL BE HIGH TODAY AHEAD OF THE FRONT WITH A NON- DIURNAL CURVE. HOWEVER...THE COLD AIRMASS...CLOUDS AND PRECIPITATION POSSIBILITIES WILL KEEP TEMPS COLD ON MONDAY. CURRENTLY THINK HIGHS WILL STRUGGLE TO GET OUT OF THE 40S AND MAY STRUGGLE TO GET OUT OF THE LOW 40S. IF THIS HAPPENS...RECORD COOL HIGHS MAY BE BROKEN FOR MONDAY...SEE CLIMATE SECTION FOR MORE INFORMATION. BILLINGS WRIGHT .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 ZONAL FLOW WILL QUICKLY RETURN TO THE UPPER AIR PATTERN...WITH BREEZY SOUTH WINDS ACROSS EASTERN KANSAS ON WEDNESDAY. THE NEXT UPPER DISTURBANCE WILL APPROACH FOR THURSDAY DRAGGING A FRONT INTO THE AREA. THIS WILL BE THE NEXT CHANCE FOR PRECIPITATION AND ANOTHER COOLER AIRMASS. HAVE DROPPED MAX TEMPS FOR THURSDAY. LITTLE IN THE WAY OF INSTABILITY...SO THINK THE PRECIPITATION WILL MAINLY BE IN THE FORM OF RAIN. THIS SYSTEM WILL EXIT ON FRIDAY...AND TEMPS WILL WARM INTO THE WEEKEND TO NEAR NORMAL. BILLINGS WRIGHT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 AN UNSETTLED AVIATION FORECAST IS EXPECTED ACROSS THE PLAINS TODAY...AS A LOW PRESSURE AREA IN SW KS BEGINS TO MOVE EAST TODAY...WITH A STRONG COLD FRONT PROGGED TO MOVE SOUTHEAST ACROSS THE AREA FOR THE AFTERNOON HOURS. SHRA/TSRA ARE POSSIBLE TO THE EAST OF SYSTEM ACROSS SE KS FOR THE MORNING HOURS AND AGAIN FOR THE AFTERNOON HOURS. SO WILL GO WITH A VCTS FOR THE KCNU TAF FOR THIS CHANCE. COULD SEE A TEMPO GROUP ADDED LATER TODAY FOR MVFR VSBYS FOR POSSIBLE STRONG TO SEVERE STORMS FOR THE AFTERNOON HOURS FOR THIS AREA AS WELL. NEXT CONCERN WILL BE THE TIMING OF THE STRONG COLD FRONT EXPECTED TO PUSH SOUTH INTO SOUTH CENTRAL KS TODAY. COLD FRONT HAS ALREADY PUSHED THROUGH KRSL AND KSLN AT THIS TIME...WITH GUSTY WINDS TO 35 KTS DEVELOPING. EXPECT THIS FRONT TO PUSH INTO KHUT/KICT BY AROUND 16-19Z WITH A DRAMATIC WIND SHIFT TO THE NORTHWEST. COULD SEE SOME POST FRONTAL SHRA/-RA AND MVFR CIGS DEVELOP AS THE FRONT PUSHES SOUTH AND THE COLDER AIR MOVES INTO THE AREA. COULD SEE THE RAIN POSSIBLY MIX WITH OR CHANGE OVER TO SNOW FOR PORTIONS OF CENTRAL AND SOUTH CENTRAL KS FOR ALL THE TAFS EXCEPT FOR KCNU BY AROUND 09Z/MON. AS THIS SNOW CHANCE DEVELOPS...COULD SEE SOME CIGS FLIRT WITH IFR ACROSS PORTIONS OF CENTRAL KS. KETCHAM && .FIRE WEATHER... ISSUED AT 347 AM CDT SUN APR 13 2014 GRASSLAND FIRE DANGER IS VERY HIGH THIS AFTERNOON AND MONDAY AFTERNOON ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. THE MOST CONCERNING PERIOD IS THAT BEFORE THUNDERSTORMS DEVELOP. AFTER THAT TIME...THE FIRE DANGER WILL DIMINISH. THE DRY AIR AIRMASS WILL CAUSE EXTREME FIRE DANGER TO BE A CONCERN TUESDAY AND WEDNESDAY WITH BREEZY SOUTH WINDS AND CURED FUELS. BILLINGS WRIGHT && .CLIMATE... ISSUED AT 347 AM CDT SUN APR 13 2014 RECORD COOL HIGHS ARE POSSIBLE ON MONDAY APRIL 14TH, 2014 COOLEST HIGH RECORDS WICHITA....45 DEGREES IN 1928 CHANUTE....47 DEGREES IN 1983 RUSSELL....44 DEGREES IN 1993 SALINA.....44 DEGREES IN 1993 BILLINGS WRIGHT && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 80 34 43 24 / 40 40 50 0 HUTCHINSON 71 31 44 24 / 40 60 30 0 NEWTON 77 31 42 24 / 40 40 40 0 ELDORADO 78 33 42 25 / 60 40 50 0 WINFIELD-KWLD 82 36 44 25 / 60 40 40 0 RUSSELL 55 29 46 23 / 60 60 10 0 GREAT BEND 56 28 46 22 / 60 60 20 0 SALINA 66 31 46 23 / 50 60 20 0 MCPHERSON 70 30 44 24 / 50 60 20 0 COFFEYVILLE 79 38 45 26 / 80 50 50 0 CHANUTE 78 36 44 24 / 80 40 50 0 IOLA 75 36 43 24 / 80 40 50 0 PARSONS-KPPF 79 37 45 24 / 80 50 50 0 && .ICT WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR KSZ032-033-047>053-067>072-082-083-091>096-098>100. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ032-033-047>052- 067-068-082-083-091-092. FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR KSZ032- 033-047>051. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
655 AM CDT SUN APR 13 2014 ...UPDATED FOR 12Z AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 347 AM CDT SUN APR 13 2014 THE MAIN STORM SYSTEM IS STILL SITTING OFF OVER THE FOUR CORNER REGION WITH AN ARM OF THE PV ANOMALY EXTENDING ACROSS KANSAS. THIS ARM HELPED TO FIRE THE ACTIVITY ON THE FRONT SATURDAY EVENING. MOISTURE TRANSPORT THIS MORNING IN AN ABUNDANTLY RICH AIRMASS HAS CAUSED THUNDERSTORMS TO DEVELOP OVER SOUTHEAST KANSAS. THE FRONT BISECTS THE FORECAST AREA FROM SALINA SOUTHWEST TO SOUTH OF GREAT BEND. THIS FRONT WILL BE THE FOCUS FOR WEATHER TODAY. BILLINGS WRIGHT && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 THIS PERIOD REMAINS VERY ACTIVE WITH A VARIETY OF WEATHER TYPES TO BRING HAZARDOUS WEATHER TO THE AREA. WILL BREAK THIS SECTION UP BASED ON TYPE OF HAZARDOUS WEATHER VS. A NARRATIVE. SEVERE WEATHER POTENTIAL: THE SEVERE WEATHER THREAT HAS BEEN WELL FORECASTED THE PAST FEW DAYS AND LITTLE HAS CHANGED REGARDING THE MAIN CONCERN. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AS IT ADVANCES SOUTHEASTWARD ACROSS THE AREA THIS AFTERNOON. THE LATEST 5Z HRRR SHOWS THUNDERSTORMS UNZIPPING ALONG THE FRONT AROUND 18-20Z JUST EAST OF WICHITA...ALONG THE KANSAS TURNPIKE. THINK AREAS ALONG AND EAST OF WICHITA WILL HAVE THE BEST CHANCE FOR THUNDERSTORMS IN AN UNSTABLE ATMOSPHERE. TEMPERATURES WILL SOAR THIS AFTERNOON AND WITH 60+ DEWPOINTS...CAPES WILL BE BETWEEN 1500-2500 J/KG. THE CAPE COMBINED WITH ADEQUATE BULK SHEAR WILL FOSTER SEVERE STORM GROWTH WITH LARGE DAMAGING HAIL THE PRIMARY THREAT. HAIL GREATER THAN THE SIZE OF GOLF BALLS AND UP TO BASEBALLS WILL BE POSSIBLE. WIND POTENTIAL: STRONG GUSTY NORTH WINDS WILL ACCOMPANY THE COLD FRONT THIS AFTERNOON. A TIGHT PRESSURE GRADIENT WILL HELP WINDS EXCEED 30 MPH WITH GUSTS UP TO 40-45 MPH. A WIND ADVISORY WAS INHERITED AND WE EXPANDED IT FURTHER EAST AND SOUTH TO COINCIDE WITH GREATEST PERCEIVED THREAT. ALSO EXTENDED THE WIND ADVISORY IN TIME TO 02Z AS THE PRESSURE GRADIENT WILL NOT LET UP UNTIL CLOSE TO MORNING. CONFIDENCE ON STRONGER WINDS PERSISTING PAST 02Z IS NOT HIGH...BUT IF THEY DO COULD SEE ADVISORY EXTENDED IN TIME. SNOW POTENTIAL: THE GUIDANCE CONTINUES TO BE TREND COLDER WITH THE AIRMASS THAT IS FOLLOWING TODAY`S COLD FRONT. THE VERTICAL COLUMN COOLS ENOUGH SUCH THAT SNOW IS GOING TO BE POSSIBLE WITH SOME LIGHT ACCUMULATIONS POSSIBLE. SOUNDINGS SHOW A PROFILE COMPLETELY BELOW ZERO FOR MUCH OF THE FORECAST AREA AS THE COLDER AIR PUSHES SOUTHEAST...THUS SNOW WILL DEVELOP DURING THE OVERNIGHT HOURS AND TRANSITION SOUTHEASTWARD. THE LATEST NAM SHOWS ACCUMULATIONS OF UPWARDS OF 2-3 INCHES...BUT CONFIDENCE ON THOSE AMOUNTS OCCURRING IS LOW. DO THINK THERE COULD BE SOME ACCUMULATIONS IN CENTRAL KANSAS...MAINLY ON GRASSY SURFACES...BUT ALSO ON THE ROADWAYS IF THE RATE IS HIGH ENOUGH. HOWEVER...ANY ACCUMULATION THAT DOES OCCUR WILL NOT LAST VERY LONG...AS WARM SURFACE TEMPERATURES WILL CAUSE IT TO MELT QUICKLY. FREEZE POTENTIAL: THE COLD AIR WILL MOVE INTO THE REGION TONIGHT...AND DOMINATE MONDAY NIGHT/TUESDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR CENTRAL KANSAS FOR TONIGHT/MONDAY MORNING FOR TEMPERATURES THAT WILL DROP BELOW 30 DEGREES. DESPITE THE STRONGER WINDS...COLD TEMPS WILL BE A CONCERN FOR SENSITIVE VEGETATION. CONFIDENCE IN THIS IS MEDIUM AND WENT THE WATCH ROUTE TO ALLOW LATER SHIFTS TO ADJUST IF NEEDED. THE BIGGEST CONCERN...HOWEVER...IS FOR MONDAY NIGHT/TUESDAY MORNING AS WIDESPREAD TEMPS BETWEEN 20-25 DEGREES ARE EXPECTED. HAVE A FREEZE WATCH FOR THE WHOLE AREA AND CONFIDENCE IS VERY HIGH THAT THIS WILL OCCUR. TAKE PRECAUTIONS TO COVER ANY SENSITIVE VEGETATION. TEMPERATURES: TEMPERATURES WILL BE HIGH TODAY AHEAD OF THE FRONT WITH A NON- DIURNAL CURVE. HOWEVER...THE COLD AIRMASS...CLOUDS AND PRECIPITATION POSSIBILITIES WILL KEEP TEMPS COLD ON MONDAY. CURRENTLY THINK HIGHS WILL STRUGGLE TO GET OUT OF THE 40S AND MAY STRUGGLE TO GET OUT OF THE LOW 40S. IF THIS HAPPENS...RECORD COOL HIGHS MAY BE BROKEN FOR MONDAY...SEE CLIMATE SECTION FOR MORE INFORMATION. BILLINGS WRIGHT .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 ZONAL FLOW WILL QUICKLY RETURN TO THE UPPER AIR PATTERN...WITH BREEZY SOUTH WINDS ACROSS EASTERN KANSAS ON WEDNESDAY. THE NEXT UPPER DISTURBANCE WILL APPROACH FOR THURSDAY DRAGGING A FRONT INTO THE AREA. THIS WILL BE THE NEXT CHANCE FOR PRECIPITATION AND ANOTHER COOLER AIRMASS. HAVE DROPPED MAX TEMPS FOR THURSDAY. LITTLE IN THE WAY OF INSTABILITY...SO THINK THE PRECIPITATION WILL MAINLY BE IN THE FORM OF RAIN. THIS SYSTEM WILL EXIT ON FRIDAY...AND TEMPS WILL WARM INTO THE WEEKEND TO NEAR NORMAL. BILLINGS WRIGHT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 AN UNSETTLED AVIATION FORECAST IS EXPECTED ACROSS THE PLAINS TODAY...AS A LOW PRESSURE AREA IN SW KS BEGINS TO MOVE EAST TODAY...WITH A STRONG COLD FRONT PROGGED TO MOVE SOUTHEAST ACROSS THE AREA FOR THE AFTERNOON HOURS. SHRA/TSRA ARE POSSIBLE TO THE EAST OF SYSTEM ACROSS SE KS FOR THE MORNING HOURS AND AGAIN FOR THE AFTERNOON HOURS. SO WILL GO WITH A VCTS FOR THE KCNU TAF FOR THIS CHANCE. COULD SEE A TEMPO GROUP ADDED LATER TODAY FOR MVFR VSBYS FOR POSSIBLE STRONG TO SEVERE STORMS FOR THE AFTERNOON HOURS FOR THIS AREA AS WELL. NEXT CONCERN WILL BE THE TIMING OF THE STRONG COLD FRONT EXPECTED TO PUSH SOUTH INTO SOUTH CENTRAL KS TODAY. COLD FRONT HAS ALREADY PUSHED THROUGH KRSL AND KSLN AT THIS TIME...WITH GUSTY WINDS TO 35 KTS DEVELOPING. EXPECT THIS FRONT TO PUSH INTO KHUT/KICT BY AROUND 16-19Z WITH A DRAMATIC WIND SHIFT TO THE NORTHWEST. COULD SEE SOME POST FRONTAL SHRA/-RA AND MVFR CIGS DEVELOP AS THE FRONT PUSHES SOUTH AND THE COLDER AIR MOVES INTO THE AREA. COULD SEE THE RAIN POSSIBLY MIX WITH OR CHANGE OVER TO SNOW FOR PORTIONS OF CENTRAL AND SOUTH CENTRAL KS FOR ALL THE TAFS EXCEPT FOR KCNU BY AROUND 09Z/MON. AS THIS SNOW CHANCE DEVELOPS...COULD SEE SOME CIGS FLIRT WITH IFR ACROSS PORTIONS OF CENTRAL KS. KETCHAM && .FIRE WEATHER... ISSUED AT 347 AM CDT SUN APR 13 2014 GRASSLAND FIRE DANGER IS VERY HIGH THIS AFTERNOON AND MONDAY AFTERNOON ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. THE MOST CONCERNING PERIOD IS THAT BEFORE THUNDERSTORMS DEVELOP. AFTER THAT TIME...THE FIRE DANGER WILL DIMINISH. THE DRY AIR AIRMASS WILL CAUSE EXTREME FIRE DANGER TO BE A CONCERN TUESDAY AND WEDNESDAY WITH BREEZY SOUTH WINDS AND CURED FUELS. BILLINGS WRIGHT && .CLIMATE... ISSUED AT 347 AM CDT SUN APR 13 2014 RECORD COOL HIGHS ARE POSSIBLE ON MONDAY APRIL 14TH, 2014 COOLEST HIGH RECORDS WICHITA....45 DEGREES IN 1928 CHANUTE....47 DEGREES IN 1983 RUSSELL....44 DEGREES IN 1993 SALINA.....44 DEGREES IN 1993 BILLINGS WRIGHT && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 81 33 43 24 / 60 50 50 0 HUTCHINSON 75 30 44 24 / 60 60 30 0 NEWTON 78 31 42 24 / 70 50 40 0 ELDORADO 79 33 42 25 / 80 40 50 0 WINFIELD-KWLD 82 35 44 25 / 80 40 40 0 RUSSELL 58 29 46 23 / 70 70 10 0 GREAT BEND 61 28 46 22 / 70 70 20 0 SALINA 67 30 46 23 / 80 70 20 0 MCPHERSON 72 30 44 24 / 60 60 20 0 COFFEYVILLE 78 38 45 26 / 80 90 50 0 CHANUTE 77 36 44 24 / 80 80 50 0 IOLA 76 36 43 24 / 80 80 50 0 PARSONS-KPPF 77 37 45 24 / 80 80 50 0 && .ICT WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR KSZ032-033-047>053-067>072-082-083-091>096-098>100. FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR KSZ032- 033-047>051. WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ032-033-047>051- 067. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
347 AM CDT SUN APR 13 2014 .SYNOPSIS... ISSUED AT 347 AM CDT SUN APR 13 2014 THE MAIN STORM SYSTEM IS STILL SITTING OFF OVER THE FOUR CORNER REGION WITH AN ARM OF THE PV ANOMALY EXTENDING ACROSS KANSAS. THIS ARM HELPED TO FIRE THE ACTIVITY ON THE FRONT SATURDAY EVENING. MOISTURE TRANSPORT THIS MORNING IN AN ABUNDANTLY RICH AIRMASS HAS CAUSED THUNDERSTORMS TO DEVELOP OVER SOUTHEAST KANSAS. THE FRONT BISECTS THE FORECAST AREA FROM SALINA SOUTHWEST TO SOUTH OF GREAT BEND. THIS FRONT WILL BE THE FOCUS FOR WEATHER TODAY. BILLINGS WRIGHT && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 THIS PERIOD REMAINS VERY ACTIVE WITH A VARIETY OF WEATHER TYPES TO BRING HAZARDOUS WEATHER TO THE AREA. WILL BREAK THIS SECTION UP BASED ON TYPE OF HAZARDOUS WEATHER VS. A NARRATIVE. SEVERE WEATHER POTENTIAL: THE SEVERE WEATHER THREAT HAS BEEN WELL FORECASTED THE PAST FEW DAYS AND LITTLE HAS CHANGED REGARDING THE MAIN CONCERN. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AS IT ADVANCES SOUTHEASTWARD ACROSS THE AREA THIS AFTERNOON. THE LATEST 5Z HRRR SHOWS THUNDERSTORMS UNZIPPING ALONG THE FRONT AROUND 18-20Z JUST EAST OF WICHITA...ALONG THE KANSAS TURNPIKE. THINK AREAS ALONG AND EAST OF WICHITA WILL HAVE THE BEST CHANCE FOR THUNDERSTORMS IN AN UNSTABLE ATMOSPHERE. TEMPERATURES WILL SOAR THIS AFTERNOON AND WITH 60+ DEWPOINTS...CAPES WILL BE BETWEEN 1500-2500 J/KG. THE CAPE COMBINED WITH ADEQUATE BULK SHEAR WILL FOSTER SEVERE STORM GROWTH WITH LARGE DAMAGING HAIL THE PRIMARY THREAT. HAIL GREATER THAN THE SIZE OF GOLF BALLS AND UP TO BASEBALLS WILL BE POSSIBLE. WIND POTENTIAL: STRONG GUSTY NORTH WINDS WILL ACCOMPANY THE COLD FRONT THIS AFTERNOON. A TIGHT PRESSURE GRADIENT WILL HELP WINDS EXCEED 30 MPH WITH GUSTS UP TO 40-45 MPH. A WIND ADVISORY WAS INHERITED AND WE EXPANDED IT FURTHER EAST AND SOUTH TO COINCIDE WITH GREATEST PERCEIVED THREAT. ALSO EXTENDED THE WIND ADVISORY IN TIME TO 02Z AS THE PRESSURE GRADIENT WILL NOT LET UP UNTIL CLOSE TO MORNING. CONFIDENCE ON STRONGER WINDS PERSISTING PAST 02Z IS NOT HIGH...BUT IF THEY DO COULD SEE ADVISORY EXTENDED IN TIME. SNOW POTENTIAL: THE GUIDANCE CONTINUES TO BE TREND COLDER WITH THE AIRMASS THAT IS FOLLOWING TODAY`S COLD FRONT. THE VERTICAL COLUMN COOLS ENOUGH SUCH THAT SNOW IS GOING TO BE POSSIBLE WITH SOME LIGHT ACCUMULATIONS POSSIBLE. SOUNDINGS SHOW A PROFILE COMPLETELY BELOW ZERO FOR MUCH OF THE FORECAST AREA AS THE COLDER AIR PUSHES SOUTHEAST...THUS SNOW WILL DEVELOP DURING THE OVERNIGHT HOURS AND TRANSITION SOUTHEASTWARD. THE LATEST NAM SHOWS ACCUMULATIONS OF UPWARDS OF 2-3 INCHES...BUT CONFIDENCE ON THOSE AMOUNTS OCCURRING IS LOW. DO THINK THERE COULD BE SOME ACCUMULATIONS IN CENTRAL KANSAS...MAINLY ON GRASSY SURFACES...BUT ALSO ON THE ROADWAYS IF THE RATE IS HIGH ENOUGH. HOWEVER...ANY ACCUMULATION THAT DOES OCCUR WILL NOT LAST VERY LONG...AS WARM SURFACE TEMPERATURES WILL CAUSE IT TO MELT QUICKLY. FREEZE POTENTIAL: THE COLD AIR WILL MOVE INTO THE REGION TONIGHT...AND DOMINATE MONDAY NIGHT/TUESDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR CENTRAL KANSAS FOR TONIGHT/MONDAY MORNING FOR TEMPERATURES THAT WILL DROP BELOW 30 DEGREES. DESPITE THE STRONGER WINDS...COLD TEMPS WILL BE A CONCERN FOR SENSITIVE VEGETATION. CONFIDENCE IN THIS IS MEDIUM AND WENT THE WATCH ROUTE TO ALLOW LATER SHIFTS TO ADJUST IF NEEDED. THE BIGGEST CONCERN...HOWEVER...IS FOR MONDAY NIGHT/TUESDAY MORNING AS WIDESPREAD TEMPS BETWEEN 20-25 DEGREES ARE EXPECTED. HAVE A FREEZE WATCH FOR THE WHOLE AREA AND CONFIDENCE IS VERY HIGH THAT THIS WILL OCCUR. TAKE PRECAUTIONS TO COVER ANY SENSITIVE VEGETATION. TEMPERATURES: TEMPERATURES WILL BE HIGH TODAY AHEAD OF THE FRONT WITH A NON- DIURNAL CURVE. HOWEVER...THE COLD AIRMASS...CLOUDS AND PRECIPITATION POSSIBILITIES WILL KEEP TEMPS COLD ON MONDAY. CURRENTLY THINK HIGHS WILL STRUGGLE TO GET OUT OF THE 40S AND MAY STRUGGLE TO GET OUT OF THE LOW 40S. IF THIS HAPPENS...RECORD COOL HIGHS MAY BE BROKEN FOR MONDAY...SEE CLIMATE SECTION FOR MORE INFORMATION. BILLINGS WRIGHT .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN APR 13 2014 ZONAL FLOW WILL QUICKLY RETURN TO THE UPPER AIR PATTERN...WITH BREEZY SOUTH WINDS ACROSS EASTERN KANSAS ON WEDNESDAY. THE NEXT UPPER DISTURBANCE WILL APPROACH FOR THURSDAY DRAGGING A FRONT INTO THE AREA. THIS WILL BE THE NEXT CHANCE FOR PRECIPITATION AND ANOTHER COOLER AIRMASS. HAVE DROPPED MAX TEMPS FOR THURSDAY. LITTLE IN THE WAY OF INSTABILITY...SO THINK THE PRECIPITATION WILL MAINLY BE IN THE FORM OF RAIN. THIS SYSTEM WILL EXIT ON FRIDAY...AND TEMPS WILL WARM INTO THE WEEKEND TO NEAR NORMAL. BILLINGS WRIGHT && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1125 PM CDT SAT APR 12 2014 MAIN AVIATION FORECAST CONCERNS WILL BE ASSOCIATED WITH A STRONG COLD FRONT SET TO MAKE ITS WAY INTO THE AREA ON SUN. A VERY STRONG COLD FRONT IS EXPECTED TO PUSH INTO THE AREA ON SUN WITH AN UNSEASONABLY COLD AIRMASS FOLLOWING BEHIND. STORMS ARE STILL EXPECTED TO DEVELOP ALONG THE FRONT AFTER 18Z...WITH THESE STORMS MAINLY AFFECTING SE KS(KCNU). SEVERE STORMS WILL BE POSSIBLE WITH THIS ACTIVITY. ANY STORMS THAT DEVELOP SHOULD BE OUT OF SE KS BY 03Z. THE SURGE OF COLD AIR WILL BRING WIDESPREAD MVFR CIGS TO CENTRAL KS BY THE EARLY AFTERNOON HOURS ALONG WITH AREAS OF RAINFALL. AFTER 03Z FEEL SOME LIGHT SNOW WILL START TO MIX WITH THE RAIN OVER CENTRAL KS WITH KRSL AND KSLN HAVING THE BEST CHANCE TO SEE SOME SNOW BEFORE 06Z. NORTH WINDS BEHIND THE FRONT WILL BE SUSTAINED IN THE 30-35 MPH RANGE WITH GUSTS 40-45 MPH. LAWSON && .FIRE WEATHER... ISSUED AT 347 AM CDT SUN APR 13 2014 GRASSLAND FIRE DANGER IS VERY HIGH THIS AFTERNOON AND MONDAY AFTERNOON ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. THE MOST CONCERNING PERIOD IS THAT BEFORE THUNDERSTORMS DEVELOP. AFTER THAT TIME...THE FIRE DANGER WILL DIMINISH. THE DRY AIR AIRMASS WILL CAUSE EXTREME FIRE DANGER TO BE A CONCERN TUESDAY AND WEDNESDAY WITH BREEZY SOUTH WINDS AND CURED FUELS. BILLINGS WRIGHT && .CLIMATE... ISSUED AT 347 AM CDT SUN APR 13 2014 RECORD COOL HIGHS ARE POSSIBLE ON MONDAY APRIL 14TH, 2014 COOLEST HIGH RECORDS WICHITA....45 DEGREES IN 1928 CHANUTE....47 DEGREES IN 1983 RUSSELL....44 DEGREES IN 1993 SALINA.....44 DEGREES IN 1993 BILLINGS WRIGHT && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 81 33 43 24 / 60 50 50 0 HUTCHINSON 75 30 44 24 / 60 60 30 0 NEWTON 78 31 42 24 / 70 50 40 0 ELDORADO 79 33 42 25 / 80 40 50 0 WINFIELD-KWLD 82 35 44 25 / 80 40 40 0 RUSSELL 58 29 46 23 / 70 70 10 0 GREAT BEND 61 28 46 22 / 70 70 20 0 SALINA 67 30 46 23 / 80 70 20 0 MCPHERSON 72 30 44 24 / 60 60 20 0 COFFEYVILLE 78 38 45 26 / 80 90 50 0 CHANUTE 77 36 44 24 / 80 80 50 0 IOLA 76 36 43 24 / 80 80 50 0 PARSONS-KPPF 77 37 45 24 / 80 80 50 0 && .ICT WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR KSZ032-033-047>053-067>072-082-083-091>096-098>100. FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR KSZ032- 033-047>051. WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING FOR KSZ032-033-047>051-067. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1133 PM CDT SAT APR 12 2014 ...UPDATED FOR 06Z AVIATION DISCUSSION... .UPDATE... ISSUED AT 750 PM CDT SAT APR 12 2014 UPDATED TO ADJUST STORM CHANCES OVERNIGHT. MAIN REASON FOR THE UPDATE WAS TO KEEP OVERNIGHT POPS TIED CLOSER TO THE BOUNDARY WHICH MEANT REMOVING THEM FOR MOST OF SOUTH CENTRAL AND ALL OF SE KS. MODELS CONTINUE TO AGREE ON BUILDING IN SOME CAPPING OVERNIGHT WHICH SHOULD KEEP THE BETTER COVERAGE ACROSS THE NORTHEAST FRINGES OF THE FORECAST AREA AFTER 06Z. LAWSON && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 258 PM CDT SAT APR 12 2014 THE 17Z RAP ANALYSIS SHOWS 0-6KM SHEAR VALUES IN THE LOWER 30 KNOT RANGE ACROSS THE FORECAST AREA...WITH MLCAPES AROUND 1000 J/KG. 12.15Z RAP FORECAST OF THESE FIELDS SHOWS AN INCREASE IN DEEP LAYER SHEAR AS THE LOW LEVEL JET DEVELOPS THIS EVENING. MLCAPE VALUES MAX OUT AROUND 2000 J/KG THIS AFTERNOON DURING PEAK HEATING...WITH DEWPOINT DEPRESSIONS REACHING OVER 25 DEGREES. AT THIS TIME...NOT THAT EXCITED FOR AFTERNOON CONVECTION ACROSS THE FORECAST AREA...THERE IS JUST TOO MUCH OF A CAP IN PLACE. THE 15Z HRRR DOES PRODUCE SOME CONVECTION OVER THE FORECAST AREA ALONG THE DRYLINE AFTER 00Z...AS DOES THE 12.12Z WRF-NMM. THIS IS MAINLY EAST OF HIGHWAY 14 AND NORTH OF HIGHWAY 400. AT THAT TIME...THE DEEP LAYER SHEAR WILL BE ENOUGH FOR ORGANIZED STORMS. THIS IS ALSO THE BEST TIME FOR A TORNADO THREAT GIVEN THAT DEWPOINT DEPRESSIONS WILL HAVE COME DOWN BY THEN...JUST NOT SURE THEY WILL HAVE COME DOWN ENOUGH. CONFIDENCE IN A TORNADO THREAT IS LOW. WE ARE LOOKING AT DISCREET SUPERCELLS...WITH THE MAIN THREAT BEING LARGE HAIL. BELIEVE THE LARGE HAIL THREAT IS QUITE HIGH GIVEN THAT THERE WILL BE LITTLE CHANCE FOR ANVIL SEEDING AND THE 0-10KM SHEAR IS GREATER THAN 90 KNOTS. THINK THAT BASEBALL HAIL OR LARGER AS A MAX HAIL SIZE IS POSSIBLE FOR ANY ISOLATED SUPERCELL ALONG THE SOUTHERN PERIPHERY OF THE DEVELOPMENT AREA. IT WILL BE INTERESTING TO SEE HOW THIS PANS OUT. TONIGHT...A COLD FRONT WILL MOVE INTO THE REGION...SLOWLY ADVANCING TO THE SOUTHEAST. THIS WILL CREATE A COMPLEX WEATHER SCENARIO FOR SUNDAY THROUGH MONDAY. BEHIND THE FRONT...STRONG NORTHERLY WINDS WILL MOVE IN AS IT PASSES. BUFKIT MOMENTUM TRANSPORT SUGGESTS WINDS OF 30 MPH WITH GUSTS TO 45 MPH. BY SUNDAY AT 18Z...THE FRONT WILL BE APPROXIMATELY LOCATED FROM EMPORIA TO WINFIELD. THE BEST CHANCE OF CONVECTION WILL BE ALONG AND EAST OF THE FRONT...MAINLY ACROSS SOUTHEAST KANSAS. MOISTURE IN THE LOW LEVELS SHOULD BE MORE FAVORABLE FOR STORM DEVELOPMENT...AS WILL FORCING IN THE MID-LEVELS. FAVORABLE SHEAR/BUOYANCY COMBINATIONS...WITH MEAN WIND VECTORS MORE PARALLEL TO THE SURFACE BOUNDARY SUGGESTS A RAPID DEVELOP OF STORMS...WITH STORMS BEING ORGANIZED INTO A LINEAR FASHION. THEREFORE...THE MAIN THREAT FOR SEVERE WEATHER SHOULD BE DAMAGING WIND...WITH LARGE HAIL A SECONDARY THREAT. AS SAID EARLIER...AS THE FRONT EXITS...STRONG NORTHERLY WINDS MOVE IN. TO FURTHER COMPLICATE MATTERS...STRONG COLD ADVECTION MOVES INTO THE REGION AS WELL. SUNDAY NIGHT...THERE WILL BE A PRECIPITATION TYPE PROBLEM AS THE COLD AIR MOVES IN. SOUNDINGS SUGGESTS A CHANGE TO SNOW NORTH OF HIGHWAY 50 BY MONDAY MORNING...WITH A MIX FURTHER SOUTH. ACCUMULATIONS ARE CERTAINLY POSSIBLE...BUT NOT SIGNIFICANT. BUFKIT SOUNDING DATA FROM THE 12Z GFS SUGGESTS THE WIND COULD LAST INTO THE MORNING HOURS OF TUESDAY. HIGH PRESSURE MOVES INTO THE REGION...WITH MONDAY NIGHT IN LINE FOR A REASONABLE FROST/FREEZE SCENARIO. WITH ALL THE COMPLEX WEATHER GOING ON AHEAD OF THIS THREAT...WILL LEAVE THIS FOR LATTER SHIFTS TO CONTEMPLATE. COOK .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 258 PM CDT SAT APR 12 2014 ANOTHER STORM SYSTEM MOVES INTO POSITION...STRETCHING FROM THE HIGH PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY WEDNESDAY. THIS SUGGESTS STRONG SOUTHERLY WINDS ACROSS THE REGION DUE TO A TIGHTENING PRESSURE GRADIENT. THIS WILL UNDOUBTEDLY BE A DANGEROUS DAY FOR FIRES. MOISTURE ADVECTION RETURNS INTO THE REGION WEDNESDAY NIGHT AND THURSDAY AS THE GULF OPENS. AT THIS TIME...THIS SYSTEM IS LOOKING RATHER STRONG AND COULD BRING SEVERE WEATHER INTO THE REGION FOR THE LATTER PORTION OF THE WEEK GIVEN THE FAVORABLE SHEAR/BUOYANCY COMBINATIONS AT THIS TIME. HIGH PRESSURE THEN MOVES INTO THE REGION THEREAFTER. COOK && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1125 PM CDT SAT APR 12 2014 MAIN AVIATION FORECAST CONCERNS WILL BE ASSOCIATED WITH A STRONG COLD FRONT SET TO MAKE ITS WAY INTO THE AREA ON SUN. A VERY STRONG COLD FRONT IS EXPECTED TO PUSH INTO THE AREA ON SUN WITH AN UNSEASONABLY COLD AIRMASS FOLLOWING BEHIND. STORMS ARE STILL EXPECTED TO DEVELOP ALONG THE FRONT AFTER 18Z...WITH THESE STORMS MAINLY AFFECTING SE KS(KCNU). SEVERE STORMS WILL BE POSSIBLE WITH THIS ACTIVITY. ANY STORMS THAT DEVELOP SHOULD BE OUT OF SE KS BY 03Z. THE SURGE OF COLD AIR WILL BRING WIDESPREAD MVFR CIGS TO CENTRAL KS BY THE EARLY AFTERNOON HOURS ALONG WITH AREAS OF RAINFALL. AFTER 03Z FEEL SOME LIGHT SNOW WILL START TO MIX WITH THE RAIN OVER CENTRAL KS WITH KRSL AND KSLN HAVING THE BEST CHANCE TO SEE SOME SNOW BEFORE 06Z. NORTH WINDS BEHIND THE FRONT WILL BE SUSTAINED IN THE 30-35 MPH RANGE WITH GUSTS 40-45 MPH. LAWSON && .FIRE WEATHER... ISSUED AT 258 PM CDT SAT APR 12 2014 THE NEXT REAL FIRE WEATHER CONCERN FOR GRASSLAND WILL NOT BE UNTIL WEDNESDAY. THAT IS WHEN STRONG SOUTHERLY WINDS DEVELOP ACROSS THE AREA FROM THE SOUTHWEST AS A RESULT OF AN INCREASING PRESSURE GRADIENT. THAT SAID...THERE IS A GOOD CHANCE OF RAINFALL SUNDAY AND INTO MONDAY. THIS WITH MILD TEMPERATURES RETURNING TO THE REGION TOWARD THE END OF THE WEEK...SHOULD SPURN MORE GROWTH OF GRASSES...AS WE TREND TOWARD LESSER CURING. COOK && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 65 76 34 45 / 10 60 50 50 HUTCHINSON 62 69 31 45 / 20 60 60 40 NEWTON 64 74 31 43 / 20 70 50 50 ELDORADO 65 75 33 44 / 10 80 50 50 WINFIELD-KWLD 66 77 35 45 / 10 80 40 50 RUSSELL 56 56 28 45 / 20 70 70 20 GREAT BEND 56 58 28 44 / 20 60 70 30 SALINA 60 64 31 46 / 30 60 70 30 MCPHERSON 61 67 30 44 / 30 60 60 40 COFFEYVILLE 65 74 39 45 / 10 60 90 40 CHANUTE 64 73 37 44 / 10 60 80 40 IOLA 64 72 36 44 / 10 70 80 40 PARSONS-KPPF 65 74 38 45 / 10 70 80 40 && .ICT WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 9 AM TO 7 PM CDT SUNDAY FOR KSZ032-033-047- 048. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
108 PM CDT SUN APR 13 2014 .AVIATION... EXPECT A MIX OF MVFR AND LOW VFR CIGS WITH UNRESTRICTED VSBYS TO BEGIN THE 18Z TAF PERIOD. HOWEVER CIGS AND VSBYS WILL LOWER AS WIDESPREAD CONVECTION MOVES WEST TO EAST ACROSS THE FOUR STATE REGION THIS AFTERNOON AND EVENING WITH PERIODS OF IFR FLIGHT WEATHER EXPECT. TSTMS WILL BRING FLIGHT HAZARDS...INCLUDING SEVERE TURBULENCE AND SURFACE WIND GUSTS TO 50 KTS. ALSO... LARGE HAIL WILL BE POSSIBLE IN THE STRONGEST STORMS. THE FIRST ROUND OF CONVECTIVE WEATHER SHOULD END BY 06Z MOST AREAS... HOWEVER CIGS MAY REMAIN IFR IN MANY LOCATIONS. ADDITIONAL TSTMS ARE POSSIBLE BEGINNING AROUND 10Z IN WESTERN AREAS AS A COLD FRONT MOVES INTO THE REGION. THE STORMS SHOULD END AFTER PASSAGE OF THE FRONT MONDAY MORNING...BUT IFR TO MVFR CIGS WILL REMAIN. SURFACE WIND SOUTHERLY 15 TO 25 KTS PREFRONTAL AND NORTHWEST 10 TO 20 POST FRONTAL MONDAY MORNING. /14/ && .PREV DISCUSSION... /ISSUED 1047 AM CDT SUN APR 13 2014/ DISCUSSION... HAVE UPDATED TO SLIGHTLY INCREASE POPS FOR THIS AFTN GIVEN CURRENT TRENDS. STORMS INCREASING ACROSS DALLAS METRO...AND THESE WILL TRACK INTO NW CWA...SO RAISED POPS TO LIKELY THERE. EXPANDED CHANCE POPS SLIGHTLY FURTHER EAST...LEAVING ONLY EXTREME EASTERN CWA IN SLIGHT CHANCE. MODELS STILL SHOWING STORMS BECOME MORE INTENSE DURG AFTN...AND ANY BREAKS IN CLOUD COVER WILL ALLOW TEMPS TO EASILY ACHIEVE 80 DEGREE FCST...AND STG LOW LVL SHEAR ALREADY IN PLACE. SO SVR ALREADY IN FCST REMAINS JUSTIFIED. LAKE WIND AGAIN TODAY APPEARS MARGINAL...WILL DECIDE LATER THIS AFTN WHETHER TO CONTINUE UNTIL 8 PM. NO OTHER CHANGES NEEDED./VII/ PREV DISCUSSION... /ISSUED 635 AM CDT SUN APR 13 2014/ AVIATION... MOSTLY MVFR CEILINGS DOMINATE THE AREAS TERMINAL EARLY THIS MORNING. LOOK FOR THESE CONDITIONS TO CONTINUE THROUGH AT LEAST THE MID MORNING HOURS WITH CEILINGS EXPECTED TO CLIMB TO NEAR 35HDFT-4KFT THROUGH THE AFTERNOON. THE EXCEPTION TO THIS SHOULD BE ACROSS OUR NE TX TERMINALS INTO THE TX TERMINAL WHERE HRRR-3KM REFLECTIVITY DATA IS IN GOOD AGREEMENT THAT CONVECTION SHOULD BEGIN DEVELOPING BETWEEN 16Z AND 21Z. WOULD OBVIOUSLY EXPECT LOWER CEILINGS WITH ANY CONVECTION THAT DEVELOPS LATER TODAY. KEPT THE MENTION OF VCTS GOING FOR THESE TERMINALS WITH A TEMPO GROUP FOR LOWER CEILINGS/VSBYS FOR LATE AFTERNOON INTO EARLY EVENING. FOR THE MLU/ELD TERMINALS...THE ARRIVAL OF CONVECTION WILL BE MUCH LATER TODAY...MORE LIKELY INTO THE EVENING/LATE OVERNIGHT HOURS. ALL THIS CONVECTION WILL DEVELOP WELL AHEAD OF THE FRONTAL BOUNDARY WHICH WILL LIKELY NOT BE MOVING INTO THE TXK/TYR TERMINALS UNTIL NEAR OR SHORTLY AFTER 12Z MON. UNTIL THAT TIME...EXPECT STRONG SOUTHERLY WINDS TODAY WITH A VERY TIGHT PRESSURE GRADIENT IN PLACE. SUSTAINED WINDS WILL BE IN THE 13-16KT RANGE WITH GUSTS LIKELY APPROACHING 22-25KTS ACROSS MOST TERMINAL LOCATIONS. GUSTS WILL LIKELY APPROACH 30KTS BY AFTERNOON AT THE TYR/GGG/TXK TERMINALS. OVERNIGHT...KEPT THE MENTION OF VCTS GOING AS NEW CONVECTION WILL LIKELY DEVELOP ACROSS N TX/S OK IN VICINITY OF THE DRYLINE/COLD FRONT MERGER AND THAT CONVECTION WOULD BE MOVING INTO OUR REGION FROM THE WEST NEAR OR SHORTLY BEFORE SUNRISE MONDAY MORNING. 13 PREV DISCUSSION... /ISSUED 523 AM CDT SUN APR 13 2014/ DISCUSSION... WATER VAPOR IMAGERY INDICATING THE LEAD UPPER LEVEL SHORT WAVE EJECTING OUT OF THE FOUR CORNERS REGION INTO THE SRN PLAINS THIS MORNING. MEANWHILE AT THE SFC...A COLD FRONT EXTENDS FROM EXTREME SE NE BACK ACROSS KS WITH A LOW JUST SOUTH OF DDC VERY NEAR THE BORDER WITH OK WHERE THE DRY LINE EXTENDS SOUTH ACROSS WRN OK/TX. FARTHER SOUTH OVER OUR REGION...A FAIR AMOUNT OF STRATOCU IS SEEN ON SATELLITE UNDER A THICK BLANKET OF CIRRUS STREAMING IN FROM THE SW AHEAD OF THE AFOREMENTIONED SHORT WAVE. THIS IS SETTING THE STAGE FOR OUR ANTICIPATED SEVERE WEATHER EVENT LATER TODAY...MORE SPECIFICALLY LATE THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO MONDAY MORNING. AS WE HAVE BEEN DISCUSSING THE PAST FEW DAYS...THIS EVENT WILL LIKELY COME IN STAGES WITH THE LEAD SHORT WAVE MOVING IN THIS AFTERNOON AND ELIMINATING THE RELATIVELY STRONG CAP IN PLACE THIS MORNING. THE NAM HAS REALLY BACKED OFF ON THE CAP HOLDING SOLID THIS AFTERNOON...COMING MORE IN LINE WITH THE GFS AND ECMWF. THIS ALSO MATCHES UP WELL WITH THE HIGH RESOLUTION HRRR SUGGESTING AMPLE REFLECTIVITY ACROSS OUR NW ZONES LATER THIS AFTERNOON. GIVEN THIS SCENARIO...THE PRIMARY THREATS WITH THIS INITIAL WAVE OF CONVECTION APPEAR TO BE LARGE HAIL AND DAMAGING WINDS WITH THE DRY LINE STILL WELL TO THE WEST OF OUR REGION. DEPENDING ON HOW WORKED OVER THE ATMOSPHERE BECOMES IN THE WAKE OF THE CONVECTION WITH THE LEAD SHORT WAVE...INSTABILITY LATER IN THE EVENING MAY NOT BE QUITE AS STRONG AS INDICATED JUST AHEAD OF THE DRY LINE AND COLD FRONT WHICH NAM GUIDANCE SUGGESTS COULD BE CAPE OF 2000-2500 J/KG. THIS WILL INDEED BEAR WATCHING AS LOW LEVEL AND DEEP LAYER SHEAR WILL BE MORE THAN SUFFICIENT TO SUPPORT DEVELOPING SUPERCELLS AND THE POSSIBILITY OF A FEW ISOLATED TORNADOES. THIS THREAT APPEARS GREATEST OVER SE OK/NE TX CLOSER TO THE TRACK OF THE SFC LOW WHICH IS EXPECTED TO RIDE ALONG THE RED RIVER VALLEY. AS THE COLD FRONT BEGINS TO OVERTAKE THE DRY LINE AROUND MIDNIGHT...THE EVENT SHOULD TRANSITION PRIMARILY TO A DAMAGING WIND THREAT AS AN INTENSE SQUALL LINE IS LIKELY TO DEVELOP ALONG THE LEADING EDGE OR JUST AHEAD OF THE COLD FRONT. EXPECT THIS LINE OF CONVECTION TO GRADUALLY TRANSITION ACROSS THE REGION THROUGHOUT THE MORNING HOURS ON MONDAY...THEN POSSIBLY FOLLOWED BY ANOTHER ROUND OF WEAKER CONVECTION WITH A SECOND SHORT WAVE QUICKLY MOVING IN BEHIND THE FRONT DURING THE AFTERNOON. THE FRONT WILL CLEAR THE REGION BY EARLY MONDAY EVENING WITH PRECIPITATION ENDING SHORTLY THEREAFTER. OUR ATTENTION THEN TURNS TO THE MUCH COOLER AIR IN THE WAKE OF THE COLD FRONT WITH AREAS OF NEAR FREEZING AND POSSIBLY SUB-FREEZING TEMPERATURES ACROSS THE NRN PARTS OF THE REGION ON TUESDAY MORNING AS WELL AS WEDNESDAY MORNING. THIS WILL BE MONITORED VERY CLOSELY AND FREEZE WARNINGS MAY BE NEEDED OVER PARTS OF NE TX/SE OK/SW AR DURING THIS TIMEFRAME. THE REMAINDER OF THE EXTENDED PERIOD WILL BRING NEAR NORMAL TEMPERATURES WITH ANOTHER COLD FRONT AND INCREASING RAIN CHANCES BY LATE THURSDAY INTO FRIDAY. A BRIEF PERIOD OF DRY WEATHER LOOKS LIKELY FOR SATURDAY WITH RAIN RETURNING ONCE AGAIN ON SUNDAY WITH AN UPPER LEVEL DISTURBANCE. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 64 66 36 62 37 / 60 40 20 10 10 MLU 66 70 36 60 36 / 60 50 40 10 10 DEQ 54 56 31 61 32 / 70 30 10 10 10 TXK 58 60 34 61 37 / 70 30 10 10 10 ELD 63 64 33 60 33 / 70 50 30 10 10 TYR 56 61 34 62 39 / 50 30 10 10 10 GGG 59 61 35 62 37 / 50 30 10 10 10 LFK 65 67 36 63 38 / 50 40 20 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153-165>167. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1047 AM CDT SUN APR 13 2014 .DISCUSSION... HAVE UPDATED TO SLIGHTLY INCREASE POPS FOR THIS AFTN GIVEN CURRENT TRENDS. STORMS INCREASING ACROSS DALLAS METRO...AND THESE WILL TRACK INTO NW CWA...SO RAISED POPS TO LIKELY THERE. EXPANDED CHANCE POPS SLIGHTLY FURTHER EAST...LEAVING ONLY EXTREME EASTERN CWA IN SLIGHT CHANCE. MODELS STILL SHOWING STORMS BECOME MORE INTENSE DURG AFTN...AND ANY BREAKS IN CLOUD COVER WILL ALLOW TEMPS TO EASILY ACHIEVE 80 DEGREE FCST...AND STG LOW LVL SHEAR ALREADY IN PLACE. SO SVR ALREADY IN FCST REMAINS JUSTIFIED. LAKE WIND AGAIN TODAY APPEARS MARGINAL...WILL DECIDE LATER THIS AFTN WHETHER TO CONTINUE UNTIL 8 PM. NO OTHER CHANGES NEEDED./VII/ && .PREV DISCUSSION... /ISSUED 635 AM CDT SUN APR 13 2014/ AVIATION... MOSTLY MVFR CEILINGS DOMINATE THE AREAS TERMINAL EARLY THIS MORNING. LOOK FOR THESE CONDITIONS TO CONTINUE THROUGH AT LEAST THE MID MORNING HOURS WITH CEILINGS EXPECTED TO CLIMB TO NEAR 35HDFT-4KFT THROUGH THE AFTERNOON. THE EXCEPTION TO THIS SHOULD BE ACROSS OUR NE TX TERMINALS INTO THE TX TERMINAL WHERE HRRR-3KM REFLECTIVITY DATA IS IN GOOD AGREEMENT THAT CONVECTION SHOULD BEGIN DEVELOPING BETWEEN 16Z AND 21Z. WOULD OBVIOUSLY EXPECT LOWER CEILINGS WITH ANY CONVECTION THAT DEVELOPS LATER TODAY. KEPT THE MENTION OF VCTS GOING FOR THESE TERMINALS WITH A TEMPO GROUP FOR LOWER CEILINGS/VSBYS FOR LATE AFTERNOON INTO EARLY EVENING. FOR THE MLU/ELD TERMINALS...THE ARRIVAL OF CONVECTION WILL BE MUCH LATER TODAY...MORE LIKELY INTO THE EVENING/LATE OVERNIGHT HOURS. ALL THIS CONVECTION WILL DEVELOP WELL AHEAD OF THE FRONTAL BOUNDARY WHICH WILL LIKELY NOT BE MOVING INTO THE TXK/TYR TERMINALS UNTIL NEAR OR SHORTLY AFTER 12Z MON. UNTIL THAT TIME...EXPECT STRONG SOUTHERLY WINDS TODAY WITH A VERY TIGHT PRESSURE GRADIENT IN PLACE. SUSTAINED WINDS WILL BE IN THE 13-16KT RANGE WITH GUSTS LIKELY APPROACHING 22-25KTS ACROSS MOST TERMINAL LOCATIONS. GUSTS WILL LIKELY APPROACH 30KTS BY AFTERNOON AT THE TYR/GGG/TXK TERMINALS. OVERNIGHT...KEPT THE MENTION OF VCTS GOING AS NEW CONVECTION WILL LIKELY DEVELOP ACROSS N TX/S OK IN VICINITY OF THE DRYLINE/COLD FRONT MERGER AND THAT CONVECTION WOULD BE MOVING INTO OUR REGION FROM THE WEST NEAR OR SHORTLY BEFORE SUNRISE MONDAY MORNING. 13 PREV DISCUSSION... /ISSUED 523 AM CDT SUN APR 13 2014/ DISCUSSION... WATER VAPOR IMAGERY INDICATING THE LEAD UPPER LEVEL SHORT WAVE EJECTING OUT OF THE FOUR CORNERS REGION INTO THE SRN PLAINS THIS MORNING. MEANWHILE AT THE SFC...A COLD FRONT EXTENDS FROM EXTREME SE NE BACK ACROSS KS WITH A LOW JUST SOUTH OF DDC VERY NEAR THE BORDER WITH OK WHERE THE DRY LINE EXTENDS SOUTH ACROSS WRN OK/TX. FARTHER SOUTH OVER OUR REGION...A FAIR AMOUNT OF STRATOCU IS SEEN ON SATELLITE UNDER A THICK BLANKET OF CIRRUS STREAMING IN FROM THE SW AHEAD OF THE AFOREMENTIONED SHORT WAVE. THIS IS SETTING THE STAGE FOR OUR ANTICIPATED SEVERE WEATHER EVENT LATER TODAY...MORE SPECIFICALLY LATE THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO MONDAY MORNING. AS WE HAVE BEEN DISCUSSING THE PAST FEW DAYS...THIS EVENT WILL LIKELY COME IN STAGES WITH THE LEAD SHORT WAVE MOVING IN THIS AFTERNOON AND ELIMINATING THE RELATIVELY STRONG CAP IN PLACE THIS MORNING. THE NAM HAS REALLY BACKED OFF ON THE CAP HOLDING SOLID THIS AFTERNOON...COMING MORE IN LINE WITH THE GFS AND ECMWF. THIS ALSO MATCHES UP WELL WITH THE HIGH RESOLUTION HRRR SUGGESTING AMPLE REFLECTIVITY ACROSS OUR NW ZONES LATER THIS AFTERNOON. GIVEN THIS SCENARIO...THE PRIMARY THREATS WITH THIS INITIAL WAVE OF CONVECTION APPEAR TO BE LARGE HAIL AND DAMAGING WINDS WITH THE DRY LINE STILL WELL TO THE WEST OF OUR REGION. DEPENDING ON HOW WORKED OVER THE ATMOSPHERE BECOMES IN THE WAKE OF THE CONVECTION WITH THE LEAD SHORT WAVE...INSTABILITY LATER IN THE EVENING MAY NOT BE QUITE AS STRONG AS INDICATED JUST AHEAD OF THE DRY LINE AND COLD FRONT WHICH NAM GUIDANCE SUGGESTS COULD BE CAPE OF 2000-2500 J/KG. THIS WILL INDEED BEAR WATCHING AS LOW LEVEL AND DEEP LAYER SHEAR WILL BE MORE THAN SUFFICIENT TO SUPPORT DEVELOPING SUPERCELLS AND THE POSSIBILITY OF A FEW ISOLATED TORNADOES. THIS THREAT APPEARS GREATEST OVER SE OK/NE TX CLOSER TO THE TRACK OF THE SFC LOW WHICH IS EXPECTED TO RIDE ALONG THE RED RIVER VALLEY. AS THE COLD FRONT BEGINS TO OVERTAKE THE DRY LINE AROUND MIDNIGHT...THE EVENT SHOULD TRANSITION PRIMARILY TO A DAMAGING WIND THREAT AS AN INTENSE SQUALL LINE IS LIKELY TO DEVELOP ALONG THE LEADING EDGE OR JUST AHEAD OF THE COLD FRONT. EXPECT THIS LINE OF CONVECTION TO GRADUALLY TRANSITION ACROSS THE REGION THROUGHOUT THE MORNING HOURS ON MONDAY...THEN POSSIBLY FOLLOWED BY ANOTHER ROUND OF WEAKER CONVECTION WITH A SECOND SHORT WAVE QUICKLY MOVING IN BEHIND THE FRONT DURING THE AFTERNOON. THE FRONT WILL CLEAR THE REGION BY EARLY MONDAY EVENING WITH PRECIPITATION ENDING SHORTLY THEREAFTER. OUR ATTENTION THEN TURNS TO THE MUCH COOLER AIR IN THE WAKE OF THE COLD FRONT WITH AREAS OF NEAR FREEZING AND POSSIBLY SUB-FREEZING TEMPERATURES ACROSS THE NRN PARTS OF THE REGION ON TUESDAY MORNING AS WELL AS WEDNESDAY MORNING. THIS WILL BE MONITORED VERY CLOSELY AND FREEZE WARNINGS MAY BE NEEDED OVER PARTS OF NE TX/SE OK/SW AR DURING THIS TIMEFRAME. THE REMAINDER OF THE EXTENDED PERIOD WILL BRING NEAR NORMAL TEMPERATURES WITH ANOTHER COLD FRONT AND INCREASING RAIN CHANCES BY LATE THURSDAY INTO FRIDAY. A BRIEF PERIOD OF DRY WEATHER LOOKS LIKELY FOR SATURDAY WITH RAIN RETURNING ONCE AGAIN ON SUNDAY WITH AN UPPER LEVEL DISTURBANCE. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 80 64 66 36 62 / 50 60 40 20 10 MLU 80 66 70 36 60 / 20 60 50 40 10 DEQ 75 54 56 31 61 / 60 70 30 10 10 TXK 78 58 60 34 61 / 60 70 30 10 10 ELD 78 63 64 33 60 / 40 70 50 30 10 TYR 79 56 61 34 62 / 50 50 30 10 10 GGG 79 59 61 35 62 / 50 50 30 10 10 LFK 81 65 67 36 63 / 50 50 40 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153-165>167. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
635 AM CDT SUN APR 13 2014 .AVIATION... MOSTLY MVFR CEILINGS DOMINATE THE AREAS TERMINAL EARLY THIS MORNING. LOOK FOR THESE CONDITIONS TO CONTINUE THROUGH AT LEAST THE MID MORNING HOURS WITH CEILINGS EXPECTED TO CLIMB TO NEAR 35HDFT-4KFT THROUGH THE AFTERNOON. THE EXCEPTION TO THIS SHOULD BE ACROSS OUR NE TX TERMINALS INTO THE TX TERMINAL WHERE HRRR-3KM REFLECTIVITY DATA IS IN GOOD AGREEMENT THAT CONVECTION SHOULD BEGIN DEVELOPING BETWEEN 16Z AND 21Z. WOULD OBVIOUSLY EXPECT LOWER CEILINGS WITH ANY CONVECTION THAT DEVELOPS LATER TODAY. KEPT THE MENTION OF VCTS GOING FOR THESE TERMINALS WITH A TEMPO GROUP FOR LOWER CEILINGS/VSBYS FOR LATE AFTERNOON INTO EARLY EVENING. FOR THE MLU/ELD TERMINALS...THE ARRIVAL OF CONVECTION WILL BE MUCH LATER TODAY...MORE LIKELY INTO THE EVENING/LATE OVERNIGHT HOURS. ALL THIS CONVECTION WILL DEVELOP WELL AHEAD OF THE FRONTAL BOUNDARY WHICH WILL LIKELY NOT BE MOVING INTO THE TXK/TYR TERMINALS UNTIL NEAR OR SHORTLY AFTER 12Z MON. UNTIL THAT TIME...EXPECT STRONG SOUTHERLY WINDS TODAY WITH A VERY TIGHT PRESSURE GRADIENT IN PLACE. SUSTAINED WINDS WILL BE IN THE 13-16KT RANGE WITH GUSTS LIKELY APPROACHING 22-25KTS ACROSS MOST TERMINAL LOCATIONS. GUSTS WILL LIKELY APPROACH 30KTS BY AFTERNOON AT THE TYR/GGG/TXK TERMINALS. OVERNIGHT...KEPT THE MENTION OF VCTS GOING AS NEW CONVECTION WILL LIKELY DEVELOP ACROSS N TX/S OK IN VICINITY OF THE DRYLINE/COLD FRONT MERGER AND THAT CONVECTION WOULD BE MOVING INTO OUR REGION FROM THE WEST NEAR OR SHORTLY BEFORE SUNRISE MONDAY MORNING. 13 && .PREV DISCUSSION... /ISSUED 523 AM CDT SUN APR 13 2014/ DISCUSSION... WATER VAPOR IMAGERY INDICATING THE LEAD UPPER LEVEL SHORT WAVE EJECTING OUT OF THE FOUR CORNERS REGION INTO THE SRN PLAINS THIS MORNING. MEANWHILE AT THE SFC...A COLD FRONT EXTENDS FROM EXTREME SE NE BACK ACROSS KS WITH A LOW JUST SOUTH OF DDC VERY NEAR THE BORDER WITH OK WHERE THE DRY LINE EXTENDS SOUTH ACROSS WRN OK/TX. FARTHER SOUTH OVER OUR REGION...A FAIR AMOUNT OF STRATOCU IS SEEN ON SATELLITE UNDER A THICK BLANKET OF CIRRUS STREAMING IN FROM THE SW AHEAD OF THE AFOREMENTIONED SHORT WAVE. THIS IS SETTING THE STAGE FOR OUR ANTICIPATED SEVERE WEATHER EVENT LATER TODAY...MORE SPECIFICALLY LATE THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO MONDAY MORNING. AS WE HAVE BEEN DISCUSSING THE PAST FEW DAYS...THIS EVENT WILL LIKELY COME IN STAGES WITH THE LEAD SHORT WAVE MOVING IN THIS AFTERNOON AND ELIMINATING THE RELATIVELY STRONG CAP IN PLACE THIS MORNING. THE NAM HAS REALLY BACKED OFF ON THE CAP HOLDING SOLID THIS AFTERNOON...COMING MORE IN LINE WITH THE GFS AND ECMWF. THIS ALSO MATCHES UP WELL WITH THE HIGH RESOLUTION HRRR SUGGESTING AMPLE REFLECTIVITY ACROSS OUR NW ZONES LATER THIS AFTERNOON. GIVEN THIS SCENARIO...THE PRIMARY THREATS WITH THIS INITIAL WAVE OF CONVECTION APPEAR TO BE LARGE HAIL AND DAMAGING WINDS WITH THE DRY LINE STILL WELL TO THE WEST OF OUR REGION. DEPENDING ON HOW WORKED OVER THE ATMOSPHERE BECOMES IN THE WAKE OF THE CONVECTION WITH THE LEAD SHORT WAVE...INSTABILITY LATER IN THE EVENING MAY NOT BE QUITE AS STRONG AS INDICATED JUST AHEAD OF THE DRY LINE AND COLD FRONT WHICH NAM GUIDANCE SUGGESTS COULD BE CAPE OF 2000-2500 J/KG. THIS WILL INDEED BEAR WATCHING AS LOW LEVEL AND DEEP LAYER SHEAR WILL BE MORE THAN SUFFICIENT TO SUPPORT DEVELOPING SUPERCELLS AND THE POSSIBILITY OF A FEW ISOLATED TORNADOES. THIS THREAT APPEARS GREATEST OVER SE OK/NE TX CLOSER TO THE TRACK OF THE SFC LOW WHICH IS EXPECTED TO RIDE ALONG THE RED RIVER VALLEY. AS THE COLD FRONT BEGINS TO OVERTAKE THE DRY LINE AROUND MIDNIGHT...THE EVENT SHOULD TRANSITION PRIMARILY TO A DAMAGING WIND THREAT AS AN INTENSE SQUALL LINE IS LIKELY TO DEVELOP ALONG THE LEADING EDGE OR JUST AHEAD OF THE COLD FRONT. EXPECT THIS LINE OF CONVECTION TO GRADUALLY TRANSITION ACROSS THE REGION THROUGHOUT THE MORNING HOURS ON MONDAY...THEN POSSIBLY FOLLOWED BY ANOTHER ROUND OF WEAKER CONVECTION WITH A SECOND SHORT WAVE QUICKLY MOVING IN BEHIND THE FRONT DURING THE AFTERNOON. THE FRONT WILL CLEAR THE REGION BY EARLY MONDAY EVENING WITH PRECIPITATION ENDING SHORTLY THEREAFTER. OUR ATTENTION THEN TURNS TO THE MUCH COOLER AIR IN THE WAKE OF THE COLD FRONT WITH AREAS OF NEAR FREEZING AND POSSIBLY SUB-FREEZING TEMPERATURES ACROSS THE NRN PARTS OF THE REGION ON TUESDAY MORNING AS WELL AS WEDNESDAY MORNING. THIS WILL BE MONITORED VERY CLOSELY AND FREEZE WARNINGS MAY BE NEEDED OVER PARTS OF NE TX/SE OK/SW AR DURING THIS TIMEFRAME. THE REMAINDER OF THE EXTENDED PERIOD WILL BRING NEAR NORMAL TEMPERATURES WITH ANOTHER COLD FRONT AND INCREASING RAIN CHANCES BY LATE THURSDAY INTO FRIDAY. A BRIEF PERIOD OF DRY WEATHER LOOKS LIKELY FOR SATURDAY WITH RAIN RETURNING ONCE AGAIN ON SUNDAY WITH AN UPPER LEVEL DISTURBANCE. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 80 64 66 36 62 / 30 60 40 20 10 MLU 80 66 70 36 60 / 20 60 50 40 10 DEQ 75 54 56 31 61 / 40 70 30 10 10 TXK 78 58 60 34 61 / 40 70 30 10 10 ELD 78 63 64 33 60 / 20 70 50 30 10 TYR 79 56 61 34 62 / 30 50 30 10 10 GGG 79 59 61 35 62 / 30 50 30 10 10 LFK 81 65 67 36 63 / 30 50 40 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153-165>167. && $$ 13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
523 AM CDT SUN APR 13 2014 .DISCUSSION... WATER VAPOR IMAGERY INDICATING THE LEAD UPPER LEVEL SHORT WAVE EJECTING OUT OF THE FOUR CORNERS REGION INTO THE SRN PLAINS THIS MORNING. MEANWHILE AT THE SFC...A COLD FRONT EXTENDS FROM EXTREME SE NE BACK ACROSS KS WITH A LOW JUST SOUTH OF DDC VERY NEAR THE BORDER WITH OK WHERE THE DRY LINE EXTENDS SOUTH ACROSS WRN OK/TX. FARTHER SOUTH OVER OUR REGION...A FAIR AMOUNT OF STRATOCU IS SEEN ON SATELLITE UNDER A THICK BLANKET OF CIRRUS STREAMING IN FROM THE SW AHEAD OF THE AFOREMENTIONED SHORT WAVE. THIS IS SETTING THE STAGE FOR OUR ANTICIPATED SEVERE WEATHER EVENT LATER TODAY...MORE SPECIFICALLY LATE THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO MONDAY MORNING. AS WE HAVE BEEN DISCUSSING THE PAST FEW DAYS...THIS EVENT WILL LIKELY COME IN STAGES WITH THE LEAD SHORT WAVE MOVING IN THIS AFTERNOON AND ELIMINATING THE RELATIVELY STRONG CAP IN PLACE THIS MORNING. THE NAM HAS REALLY BACKED OFF ON THE CAP HOLDING SOLID THIS AFTERNOON...COMING MORE IN LINE WITH THE GFS AND ECMWF. THIS ALSO MATCHES UP WELL WITH THE HIGH RESOLUTION HRRR SUGGESTING AMPLE REFLECTIVITY ACROSS OUR NW ZONES LATER THIS AFTERNOON. GIVEN THIS SCENARIO...THE PRIMARY THREATS WITH THIS INITIAL WAVE OF CONVECTION APPEAR TO BE LARGE HAIL AND DAMAGING WINDS WITH THE DRY LINE STILL WELL TO THE WEST OF OUR REGION. DEPENDING ON HOW WORKED OVER THE ATMOSPHERE BECOMES IN THE WAKE OF THE CONVECTION WITH THE LEAD SHORT WAVE...INSTABILITY LATER IN THE EVENING MAY NOT BE QUITE AS STRONG AS INDICATED JUST AHEAD OF THE DRY LINE AND COLD FRONT WHICH NAM GUIDANCE SUGGESTS COULD BE CAPE OF 2000-2500 J/KG. THIS WILL INDEED BEAR WATCHING AS LOW LEVEL AND DEEP LAYER SHEAR WILL BE MORE THAN SUFFICIENT TO SUPPORT DEVELOPING SUPERCELLS AND THE POSSIBILITY OF A FEW ISOLATED TORNADOES. THIS THREAT APPEARS GREATEST OVER SE OK/NE TX CLOSER TO THE TRACK OF THE SFC LOW WHICH IS EXPECTED TO RIDE ALONG THE RED RIVER VALLEY. AS THE COLD FRONT BEGINS TO OVERTAKE THE DRY LINE AROUND MIDNIGHT...THE EVENT SHOULD TRANSITION PRIMARILY TO A DAMAGING WIND THREAT AS AN INTENSE SQUALL LINE IS LIKELY TO DEVELOP ALONG THE LEADING EDGE OR JUST AHEAD OF THE COLD FRONT. EXPECT THIS LINE OF CONVECTION TO GRADUALLY TRANSITION ACROSS THE REGION THROUGHOUT THE MORNING HOURS ON MONDAY...THEN POSSIBLY FOLLOWED BY ANOTHER ROUND OF WEAKER CONVECTION WITH A SECOND SHORT WAVE QUICKLY MOVING IN BEHIND THE FRONT DURING THE AFTERNOON. THE FRONT WILL CLEAR THE REGION BY EARLY MONDAY EVENING WITH PRECIPITATION ENDING SHORTLY THEREAFTER. OUR ATTENTION THEN TURNS TO THE MUCH COOLER AIR IN THE WAKE OF THE COLD FRONT WITH AREAS OF NEAR FREEZING AND POSSIBLY SUB-FREEZING TEMPERATURES ACROSS THE NRN PARTS OF THE REGION ON TUESDAY MORNING AS WELL AS WEDNESDAY MORNING. THIS WILL BE MONITORED VERY CLOSELY AND FREEZE WARNINGS MAY BE NEEDED OVER PARTS OF NE TX/SE OK/SW AR DURING THIS TIMEFRAME. THE REMAINDER OF THE EXTENDED PERIOD WILL BRING NEAR NORMAL TEMPERATURES WITH ANOTHER COLD FRONT AND INCREASING RAIN CHANCES BY LATE THURSDAY INTO FRIDAY. A BRIEF PERIOD OF DRY WEATHER LOOKS LIKELY FOR SATURDAY WITH RAIN RETURNING ONCE AGAIN ON SUNDAY WITH AN UPPER LEVEL DISTURBANCE. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 80 64 66 36 62 / 30 60 40 20 10 MLU 80 66 70 36 60 / 20 60 50 40 10 DEQ 75 54 56 31 61 / 40 70 30 10 10 TXK 78 58 60 34 61 / 40 70 30 10 10 ELD 78 63 64 33 60 / 20 70 50 30 10 TYR 79 56 61 34 62 / 30 50 30 10 10 GGG 79 59 61 35 62 / 30 50 30 10 10 LFK 81 65 67 36 63 / 30 50 40 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: LAZ001>006-010>014-017>022. OK...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153-165>167. && $$ 19
AREA FORECAST DISCUSSION
NWS CARIBOU ME
548 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH ACROSS THE REGION LATE TONIGHT INTO MONDAY MORNING WITH UNSEASONABLY WARM AIR ACROSS THE AREA MONDAY AFTERNOON INTO TUESDAY. A COLD FRONT FROM QUEBEC WILL APPROACH TUESDAY AND CROSS THE REGION TUESDAY NIGHT. HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY. && .NEAR TERM /THROUGH MONDAY/... 530 PM UPDATE: CHGS THIS UPDATE INCLUDE: 1) INCREASING POPS TO 100 PERCENT FOR TNGT FOR SPCLY THE N PTN OF THE FA XPCTD TO GET A SECOND ROUND OF PRECIP OF GREATER THAN A QUARTER INCH LATER TNGT...2) DELAY THE CHG OVR TO RN ACROSS THE NRN THIRD OF THE FA A COUPLE OF MORE HRS LATER INTO THE ERLY EVE BASED ON HRRR MODEL FCST RADAR REF WHICH SHOWS BRIGHT BANDING CLRG THE ST JOHN VLY DURING THE MID EVE HRS. THIS RESULTED IN REDUCING SNFL IN THE CURRENT 18-24Z TM FRAME OVR PARTICULARLY NE PTNS OF THE FA... BUT ADDING A LITTLE MORE IN THE 00-06Z TM FRAME OVR THE FAR N TO TAKE INTO CONSIDERATION THE SLIGHT DELAY IN THE CHGOVR TO ALL RN. MAX SN RATIOS IN EVEN THE ALL SN PRECIP TYPES WERE HELD DOWN TO 8:1 GIVEN TEMPS SLOWLY RISING TO AND ABV FZG ACROSS THE FAR N OVR THE NEXT FEW HRS. LASTLY...3) LATEST OBSVD HRLY TEMPS WERE MERGED TO FCST MSLY MODEL TEMPS THRU THE NGT TO RE-CONSTRUCT THE FCST HRLY TEMP TREND ACROSS THE REGION TO MON MORN...WHICH MSLY FEATURED SLOWLY RISING TEMPS OVRNGT. ORGNL DISC: LOW PRES CURRENTLY CNTRD OVR THE ERN GRT LAKES W/ A WELL DEFINED WARM FRONT ACROSS SERN ONT AND NRN NYS THEN SEWRD ACROSS THE GULF OF MAINE. ACROSS OUR REGION TO THE N OF THIS WARM FRONT...VERY CHILLY AIR W/ OVERRUNNING SNOW AND RAIN. SNOW HAS ACCUMULATED UP TO AN INCH OR TWO ACROSS THE NRN AREAS THIS AFTN AND THIS TREND WILL CONT INTO THE ERLY EVE HRS BEFORE MILD AIR BEGINS TO FINALLY LIFT UP ACROSS THE REGION. AFTER THE INITIAL SURGE OF OVERRUNNING SNOW AND RAIN PASSES NXT FEW HRS...ALL MODEL GUIDANCE ADVERTISES ANOTHER SLUG OF MOISTURE TO SPREAD ACROSS MAINLY NRN AREAS LATER THIS EVE BEFORE IT SLIDES E OF THE AREA ERLY MON AM. THIS SECOND SLUG SHOULD MOSTLY BE IN THE FORM OF RAIN BUT COULD STILL BE SOME WET SNOW ACROSS THE FAR N FOR A PD THIS EVE... OTHERWISE...THE STRONG WARM FRONT IS FCST TO LIFT NEWRD UP ACROSS THE AREA LATER TNGT INTO MON AM. THIS WILL SET THE STAGE FOR MUCH WARMER AIR TO OVERSPREAD THE AREA BY MON AFTN. TEMPS TNGT SHOULD REMAIN STEADY OR SLOWLY RISE W/ TEMPS ON MON TO BURST INTO THE 60S MOST AREAS AND PSBLY EVEN TOUCH 70 IN A FEW AREAS AWAY FROM THE COAST. THIS WILL LEAD TO A MUCH MORE RAPID RATE OF SNOW MELT WHICH WILL LEAD TO HEIGHTENED FLOODING CONCERNS AND THESE ARE ADDRESSED IN MORE DETAIL IN THE HYDRO SECTION BLO. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... MONDAY NIGHT WILL BE UNSEASONABLY MILD AS SOUTHWEST WINDS IN ADVANCE OF AN APPROACHING COLD FRONT WILL RESULT IN OVERNIGHT LOW TEMPERATURES IN THE UPPER 40S TO NEAR 50 DEGREES ACROSS MOST OF THE FORECAST AREA. EXPECT MOSTLY CLOUDY SKIES ALONG WITH THE CHANCE FOR SHOWERS. THE UNSEASONABLY WARM TEMPERATURES WILL RESULT IN CONTINUED SNOW MELT AND CONTINUED ICE MOVEMENT MONDAY NIGHT. THE COLD FRONT WILL CONTINUE TO SLOWLY APPROACH THE REGION DURING TUESDAY. WEAK AREAS OF LOW PRESSURE WILL MOVE UP ALONG THE APPROACHING COLD FRONT RESULT IN WIDESPREAD RAINFALL DEVELOPING ACROSS THE REGION BY TUESDAY AFTERNOON AND CONTINUING RIGHT THROUGH MUCH OF TUESDAY NIGHT AS THE FRONT SLOWLY CROSSES THE AREA. THE COMBINATION OF RAIN AND UNSEASONABLY WARM TEMPERATURES WILL RESULT IN CONTINUED SNOW MELT AND ICE MELT/MOVEMENT ON AREA RIVERS...ESPECIALLY ACROSS CENTRAL AND NORTHERN AREAS. THIS WILL INCREASE THE POTENTIAL FOR ICE JAMS ON AREA RIVERS. A FLOOD WATCH IS IN EFFECT THROUGH WEDNESDAY. PLEASE SEE THE HYDROLOGY SECTION BELOW FOR MORE DETAILED INFORMATION REGRADING HYDROLOGIC CONCERNS. THE COLD FRONT WILL MOVE EAST OF THE REGION EARLY WEDNESDAY. MUCH COLDER AIR FILTERING IN BEHIND THE COLD FRONT MAY RESULT IN ANY LINGERING RAIN SHOWERS CHANGING TO SNOW SHOWERS BEFORE ENDING LATER WEDNESDAY MORNING. HIGH PRESSURE WILL THEN BEGIN TO BUILD EAST ACROSS THE REGION BY WEDNESDAY AFTERNOON RESULTING IN INCREASING SUNSHINE ALONG WITH BRISK NORTHWEST WINDS. HIGH TEMPERATURES ON WEDNESDAY WILL BE BELOW NORMAL WITH HIGHS RANGING FROM THE UPPER 30S TO NEAR 40 NORTH AND LOW TO MID 40S CENTRAL AND DOWNEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS MAINE WEDNESDAY NIGHT. THIS AREA OF HIGH PRESSURE WILL DOMINATE THE WEATHER KEEPING CONDITIONS COOL AND DRY. THE CENTER OF THIS HIGH WILL MOVE EAST OF MAINE GOING INTO FRIDAY MORNING. THIS WILL BRING RETURN FLOW ACROSS THE REGION AND BRING HIGH TEMPERATURES GENERALLY BACK INTO THE LOWER TO MID 50S ACROSS THE AREA BY FRIDAY. THEN MODELS BEGIN FALLING OUT OF AGREEMENT AS WE GET OUT TOWARD SATURDAY. GFS IS INDICATING UPPER LEVEL LOW AND ASSOCIATED SURFACE LOW AND FRONT PROGRESSING EAST SATURDAY INTO SUNDAY. HOWEVER THE ECMWF SHOWS THIS SYSTEM STAYING SPLIT AND GENERALLY GIVING LITTLE TO NO PRECIP FROM SATURDAY TO SUNDAY. SINCE WE HAVE PLENTY TIME TO CONTINUE TO LOOK AT SUBSEQUENT RUNS FOR CONSISTENCY WILL LEAN TOWARD THE MODEL BLEND APPROACH WITH LITTLE NEED FOR MAJOR ADJUSTMENTS. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... NEAR TERM: IFR CONDS ACROSS THE FAR N W/ SOME SNOW W/ MVFR CENTRAL/SRN AREAS ATTM... IFR SHOULD DVLP SRN TAF SITES THIS AFTN/EVE W/ IFR CONDS DVLPG AT ALL THE TAF SITES BY THE LATE EVE HRS. EXPECT WDSPRD IFR THE THRU TNGT INTO MON AS A VERY WARM AND INCREASINGLY MOIST FLOW DVLPS ACROSS THE AREA... SHORT TERM: WIDESPREAD MVFR/IFR CONDITIONS ARE EXPECTED MONDAY NIGHT THROUGH TUESDAY NIGHT IN DEVELOPING RAIN. MVFR CONDITIONS ARE POSSIBLE EARLY WEDNESDAY MORNING BEFORE HIGH PRESSURE BUILD EAST WITH VFR CONDITIONS AND BRISK NORTHWEST WINDS. CONDITIONS ARE EXPECTED TO STAY VFR THROUGH FRIDAY. && .MARINE... NEAR TERM: A BRISK SRLY GRADIENT AHEAD OF A SLOW MOVG COLD FRONT APPROACHING FROM THE W WILL KEEP THE THREAT OF SCA CONDS GOING ACROSS THE WATERS INTO TUE... SHORT TERM: GUSTY SOUTHWEST WINDS IN ADVANCE OF AN APPROACHING COLD FRONT WILL RESULT IN SMALL CRAFT ADVISORY FOR BOTH WINDS/SEAS THROUGH MONDAY NIGHT WITH EVEN A FEW GUSTS TO 35 KT POSSIBLE MONDAY NIGHT THROUGH TUESDAY NIGHT. THEREFORE...THE SMALL CRAFT ADVISORY WILL LIKELY NEED TO BE EXTENDED BY LATER SHIFTS. GUSTY NORTHWEST WINDS WITH THE PASSAGE OF THE COLD FRONT WILL RESULT IN A CONTINUED CHANCE FOR SMALL CRAFT ADVISORY CONDITIONS ON WEDNESDAY. VISIBILITY WILL BE REDUCED TO 1 TO 3 NM AT TIMES IN RAIN TUESDAY AND TUESDAY NIGHT. && .HYDROLOGY... WILL CONT FLOOD WATCHES... MUCH COLDER AIR ACROSS THE REGION TODAY HAS SLOWED SNOW MELT AND RUNOFF BUT AREA RIVERS/STREAM CONT TO SLOWLY RISE. THIS TREND SHOULD ONLY INCREASE OVER THE NXT SEVERAL DAYS. COLD TEMPS TODAY WILL GIVE WAY TO VERY MILD CONDS ON MON AS A STALLED FRONTAL BNDRY S OF THE AREA LIFTS UP ACROSS THE AREA AS WARM FRONT ERLY MON. IN ADDITION...RAIN/SNOW ACROSS THE AREA TODAY INTO TNGT WILL ADD ADDITIONAL PRECIP AMOUNTS OF .25-.75 INCHES ACROSS THE REGION BY ERLY MON AM. AS A RESULT...THE MAIN THREAT PD FOR THE POTENTIAL FOR FLOODING REMAINS MONDAY THROUGH WEDNESDAY EVENING. MILDER TEMPERATURES ON MON WILL PRODUCE SIGNIFICANT SNOW MELT ACROSS THE REGION WHICH WILL CONTRIBUTE TO RISING RIVER LEVELS WHICH COULD CAUSE ICE TO MOVE AND POSSIBLY JAM. TEMPERATURES WILL REMAIN ABOVE FREEZING MONDAY NIGHT IN ADVANCE OF AN APPROACHING COLD FRONT AND RAIN CHANCES WILL ALSO BEGIN TO INCREASE LATER MONDAY NIGHT. MODERATE TO HEAVY RAIN WILL OCCUR ACROSS THE REGION TUESDAY THROUGH EARLY TUESDAY NIGHT IN ADVANCE OF THE SLOW MOVING COLD FRONT ALONG WITH STILL MILD TEMPERATURES AND SIGNIFICANT SNOW MELT CONTINUING. ALL THIS WILL ONLY ACT TO INCREASE THE THREAT OF FLOODING FROM ICE JAMS AND RISING RIVER LEVELS THROUGH MID WEEK... && .CAR WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH FROM MONDAY MORNING THROUGH WEDNESDAY EVENING FOR MEZ001>006-010-011-015>017-029>032. MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT TUESDAY FOR ANZ050>052. && $$ NEAR TERM...VJN SHORT TERM...DUDA LONG TERM...JORDAN AVIATION...VJN/DUDA MARINE...VJN/DUDA HYDROLOGY...KHW
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAY ME
547 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM FRONT WILL PUSH NORTH OF THE REGION OVERNIGHT. A WARM SOUTHERLY FLOW WILL SET UP AHEAD OF LOW PRESSURE MOVING NORTHEAST OUT OF THE GREAT LAKES ON MONDAY. A SLOW MOVING TRAILING COLD FRONT WILL APPROACH FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL GRADUALLY CROSS THE AREA TUESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST ON WEDNESDAY AND WILL CREST OVER THE REGION ON THURSDAY. HIGH PRESSURE WILL SHIFT OFF TO THE EAST ON FRIDAY. && .NEAR TERM /THROUGH MONDAY/... UPDATE...MINOR TWEAKS TO ADJUST FOR CURRENT OBSERVATIONAL TRENDS. LLVL CLOUDS AND SHRA CONTINUE TO QUICKLY MOVE NEWD. EXPECT THAT WITH LOSS OF DAYTIME HEATING STRATUS WILL REDEVELOP FOR COASTAL ME. MUCH OF NH SHOULD REMAIN MOSTLY CLEAR THRU THE NIGHT WITH JUST SOME PATCHY FOG. AS ELEVATED MIXED LAYER MOVES IN ALOFT LATE THIS EVENING SOME SHRA OR TSTMS ARE POSSIBLE ON THE LEADING EDGE. LATEST HRRR RUNS CONTINUE TO ADVERTISE THIS...SO HAVE ADDED SOME THUNDER TO THE GRIDS AROUND MIDNIGHT AND LATER. PREVIOUS DISCUSSION...JUST GOT A REPORT OF SOME GRAUPEL OUT OF CONVECTIVE SHOWERS IN WRN ME. THESE SHRA WILL CROSS THE CAPITAL AREA AND MID COAST OVER THE NEXT HOUR OR TWO. ANY PRECIP WILL WIND DOWN BY 5 OR 6 PM...AND THE REST OF THE NIGHT LOOKS DRY. TOUGH PART OF FORECAST FOR TONIGHT IS WHERE AND WHETHER THE MARINE/COLD LYR MAXES OUT BEFORE SUNSET. THIS IS ALREADY HAPPENING IN INTERIOR SRN NH...WHERE TEMPS HAVE JUMPED WELL INTO THE 50S IN SOME SPOTS. IN AREAS THAT DO BREAK OUT...MINS TONIGHT WILL DROP OFF SOME. HOWEVER...ALONG THE COAST AND AND IN THE ERN INTERIOR ZONES...WHERE THE MARINE LYR IN ENTRENCHED...IT SEEMS LESS LKLY THAT THE SW WINDS WILL MIX DOWN...AND LOW CLOUDS AND COOLER TEMPS WILL HOLD THRU THE NIGHT. HERE..MINS ARE LKLY TO OCCUR AROUND SUNSET...AS TEMPS WILL LKLY RISE VERY SLOWLY OVERNIGHT. && .SHORT TERM /MONDAY NIGHT/... WILL SEE LINGERING STRATUS AND FOG IN THE MORNING...ESPECIALLY ALONG THE COAST FROM PORTLAND EAST...ALTHOUGH THERE WILL BE ENOUGH SSW FLOW TO BREAK OUT MOST EVERYWHERE BY MID-LATE MORNING. OTHERWISE LOOK FOR SKIES TO BE SUNNY7 TO P/SUNNY THROUGH THE DAY WITH STRONG SW FLOW MIXING DOWN VERY WARM AIR IN THE 925-850MB...WHICH IN THE WARMER INLAND AREAS TRANSLATES TO HIGHS IN THE 70S. ALONG THE COAST S OF CASCO BAY...WILL LKLY SEE SOME TURNING OF THE WINDS TO THE S...WHICH WILL KEEP HIGHS IN THE 60S. ALONG THE MID COAST..HIGHS WILL BE LIMITED TO THE MID 50S TO LOW 60S. WELL DEFINED COLD FRONT CROSSES THE GREAT LAKES AND MOVES INTO WRN NY MON NIGHT. AND THE SSW FLOW WILL PERSIST THROUGH THE NIGHT. THIS WILL KEEP MINS ON THE MILDER SIDE...50S S...AND GENERALLY 40S ELSEWHERE. A FEW SHOWERS COULD DEVELOP AFTER MIDNIGHT ACROSS NH AHEAD OF THE FRONT. ALSO...COASTAL FOG AND STRATUS IS LKLY TO ROLL IN MON EVENING AND PERSIST THROUGH THE NIGHT. IT WILL LKLY MAKE IT ALL THE WAY TO THE FOOTHILLS. && .LONG TERM /TUESDAY THROUGH SUNDAY/... SLOW MOVING COLD FRONT WILL APPROACH FROM THE WEST ON TUESDAY. EXPECT RAIN TO PUSH INTO NEW HAMPSHIRE AND WESTERN MAINE TUESDAY MORNING AND WILL OVERSPREAD THE REMAINDER OF THE FORECAST AREA THROUGH MID AFTERNOON. RAIN WILL COME DOWN HEAVY AT TIMES LATE TUESDAY AFTERNOON AND EVENING AS THE FRONT PUSHES THROUGH THE AREA. WILL LIKELY SEE SOME PROBLEMS OF AREA RIVERS AS ONE TO ONE AND A HALF INCHES OF RAINFALL COMBINES WITH RAPID SNOW MELT AND ICE JAMS ON AREA RIVES. TAIL END OF THE PRECIPITATION WILL LIKELY END AS A BRIEF PERIOD OF WET SNOW OR SLEET AROUND MIDNIGHT TUESDAY NIGHT BUT NOT LOOKING FOR MUCH IF ANY ACCUMULATION. RAIN AND MIXED PRECIP WILL QUICKLY SHIFT EAST OF THE FORECAST AREA AND SKIES WILL CLEAR DOWNWIND OF THE MOUNTAINS BEFORE DAYBREAK. SHOULD BE A MOSTLY SUNNY BUT BREEZY START TO WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE EAST. WINDS WILL QUICKLY DIMINISH TUESDAY AFTERNOON AS TIGHTER GRADIENT SHIFTS EAST AND VARIABLE CLOUDINESS IN THE NORTH WILL ALSO DIMINISH DURING THE AFTERNOON. TEMPERATURES WILL AVERAGE OUT BELOW NORMAL WITH HIGHS RANGING THROUGH THE 30S NORTH AND IN THE LOWER TO MID 40S SOUTH. CLEAR SKIES AND LIGHT WINDS FOR WEDNESDAY NIGHT WILL ALLOW TEMPS TO DROP WELL BELOW NORMAL WITH READINGS DIPPING INTO THE TEENS NORTH AND 20S SOUTH. HIGH PRESSURE WILL SLOWLY SHIFT OFF TO THE EAST THURSDAY AND FRIDAY RESULTING IN TWO FAIRLY NICE DAYS ALONG WITH MODERATING TEMPS. WILL SEE SOME HIGH CLOUDINESS ON FRIDAY BUT BOTH DAYS SHOULD ALSO FEATURE A FAIR AMOUNT OF SUN. EXPECT TEMPS NEAR NORMAL ON THURSDAY WITH HIGHS FROM THE MID 40S TO LOWER 50S. FRIDAY LOOKING SLIGHTLY WARMER WITH HIGHS THROUGHOUT THE REGION IN THE LOWER TO MID 50S...BUT SLIGHTLY COOLER ALONG THE COAST. LOW PRESSURE OVER THE GREAT LAKES WILL DRIVE AN OCCLUDED FRONT TOWARD THE REGION ON SATURDAY. AFTER SOME MORNING SUN CLOUDS WILL BE ON THE INCREASE WITH AFTERNOON SHOWERS PUSHING IN FROM THE WEST. UPPER LOW SWINGING IN FROM THE WEST SATURDAY NIGHT WILL KEEP SHOWER ACTIVITY GOING AND WILL LIKELY BRING ALONG ENOUGH COLDER AIR TO PRODUCE SOME SNOW AT HIGHER ELEVATIONS IN THE NORTH INTO SUNDAY. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... SHORT TERM...COASTAL TERMINAL AND KAUG WILL DROP TO IFR OR LOWER IN LOW STRATUS AND FOG THIS EVENING...AND WILL IMPROVE TO VFR LATE MORNING TO MIDDAY. AT KCON/KLEB/KHIE...WILL SEE SOME FOG AND LOW CLOUDS...PROBABLY REACHING IFR...BUT PROB NOT UNTIL AFTER MIDNIGHT. THEY IMPROVE TO VFR AFTER SUNRISE. AFTER VFR MON AFTERNOON...THE COASTAL TERMINALS LOOK TO FALL TO IFR OR LOWER AGAIN IN STRATUS/FOG AROUND SUNSET...AND THE OTHER TERMINALS WILL FOLLOW SUIT BY MIDNIGHT. LONG TERM...IFR/LIFR CEILINGS/VSBY TUESDAY...IMPROVING TO VFR LATE TUESDAY NIGHT. VFR WEDNESDAY THROUGH FRIDAY. && .MARINE... SHORT TERM...SCA EXTENDED THROUGH MON NIGHT. PERSISTENT SW FLOW WILL PERSIST TONIGHT INTO TUE...AND WILL FRESHEN LATE MONDAY AND MON NIGHT...APPROACHING GALES. LONG TERM...GALES LIKELY TUESDAY THROUGH EARLY WEDNESDAY. && .HYDROLOGY... THE COMBINATION RAPID SNOW MELT AND SOME PERIODS OF RAIN WILL KEEP MOST RIVERS RUNNING HIGH THROUGH THE PERIOD. ICE MOVEMENT WILL ADD TO THE UNPRECICTABILITY OF WATER LEVELS ON AREA RIVERS TODAY AND MONDAY. A MORE SIGNIFICANT FLOODING THREAT IS EXPECTED TUESDAY AND WENESDAY AS POTENTIALLY HEAVY RAINFALL ASSOCIATED WITHA COLD FRONT MOVES ACROSS THE REGION. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR MEZ007>009-012>014- 018>028. NH...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR NHZ001>010-013-014. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ150>154. && $$ NEAR TERM...LEGRO
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
545 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM FRONT WILL PUSH NORTH OF THE REGION OVERNIGHT. A WARM SOUTHERLY FLOW WILL SET UP AHEAD OF LOW PRESSURE MOVING NORTHEAST OUT OF THE GREAT LAKES ON MONDAY. A SLOW MOVING TRAILING COLD FRONT WILL APPROACH FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL GRADUALLY CROSS THE AREA TUESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST ON WEDNESDAY AND WILL CREST OVER THE REGION ON THURSDAY. HIGH PRESSURE WILL SHIFT OFF TO THE EAST ON FRIDAY. && .NEAR TERM /THROUGH MONDAY/... UPDATE...MINOR TWEAKS TO ADJUST FOR CURRENT OBSERVATIONAL TRENDS. LLVL CLOUDS AND SHRA CONTINUE TO QUICKLY MOVE NEWD. EXPECT THAT WITH LOSS OF DAYTIME HEATING STRATUS WILL REDEVELOP FOR COASTAL ME. MUCH OF NH SHOULD REMAIN MOSTLY CLEAR THRU THE NIGHT WITH JUST SOME PATCHY FOG. AS ELEVATED MIXED LAYER MOVES IN ALOFT LATE THIS EVENING SOME SHRA OR TSTMS ARE POSSIBLE ON THE LEADING EDGE. LATEST HRRR RUNS CONTINUE TO ADVERTISE THIS...SO HAVE ADDED SOME THUNDER TO THE GRIDS AROUND MIDNIGHT AND LATER. PREVIOUS DISCUSSION...JUST GOT A REPORT OF SOME GRAUPEL OUT OF CONVECTIVE SHOWERS IN WRN ME. THESE SHRA WILL CROSS THE CAPITAL AREA AND MID COAST OVER THE NEXT HOUR OR TWO. ANY PRECIP WILL WIND DOWN BY 5 OR 6 PM...AND THE REST OF THE NIGHT LOOKS DRY. TOUGH PART OF FORECAST FOR TONIGHT IS WHERE AND WHETHER THE MARINE/COLD LYR MAXES OUT BEFORE SUNSET. THIS IS ALREADY HAPPENING IN INTERIOR SRN NH...WHERE TEMPS HAVE JUMPED WELL INTO THE 50S IN SOME SPOTS. IN AREAS THAT DO BREAK OUT...MINS TONIGHT WILL DROP OFF SOME. HOWEVER...ALONG THE COAST AND AND IN THE ERN INTERIOR ZONES...WHERE THE MARINE LYR IN ENTRENCHED...IT SEEMS LESS LKLY THAT THE SW WINDS WILL MIX DOWN...AND LOW CLOUDS AND COOLER TEMPS WILL HOLD THRU THE NIGHT. HERE..MINS ARE LKLY TO OCCUR AROUND SUNSET...AS TEMPS WILL LKLY RISE VERY SLOWLY OVERNIGHT. && .SHORT TERM /MONDAY NIGHT/... WILL SEE LINGERING STRATUS AND FOG IN THE MORNING...ESPECIALLY ALONG THE COAST FROM PORTLAND EAST...ALTHOUGH THERE WILL BE ENOUGH SSW FLOW TO BREAK OUT MOST EVERYWHERE BY MID-LATE MORNING. OTHERWISE LOOK FOR SKIES TO BE SUNNY7 TO P/SUNNY THROUGH THE DAY WITH STRONG SW FLOW MIXING DOWN VERY WARM AIR IN THE 925-850MB...WHICH IN THE WARMER INLAND AREAS TRANSLATES TO HIGHS IN THE 70S. ALONG THE COAST S OF CASCO BAY...WILL LKLY SEE SOME TURNING OF THE WINDS TO THE S...WHICH WILL KEEP HIGHS IN THE 60S. ALONG THE MID COAST..HIGHS WILL BE LIMITED TO THE MID 50S TO LOW 60S. WELL DEFINED COLD FRONT CROSSES THE GREAT LAKES AND MOVES INTO WRN NY MON NIGHT. AND THE SSW FLOW WILL PERSIST THROUGH THE NIGHT. THIS WILL KEEP MINS ON THE MILDER SIDE...50S S...AND GENERALLY 40S ELSEWHERE. A FEW SHOWERS COULD DEVELOP AFTER MIDNIGHT ACROSS NH AHEAD OF THE FRONT. ALSO...COASTAL FOG AND STRATUS IS LKLY TO ROLL IN MON EVENING AND PERSIST THROUGH THE NIGHT. IT WILL LKLY MAKE IT ALL THE WAY TO THE FOOTHILLS. && .LONG TERM /TUESDAY THROUGH SUNDAY/... SLOW MOVING COLD FRONT WILL APPROACH FROM THE WEST ON TUESDAY. EXPECT RAIN TO PUSH INTO NEW HAMPSHIRE AND WESTERN MAINE TUESDAY MORNING AND WILL OVERSPREAD THE REMAINDER OF THE FORECAST AREA THROUGH MID AFTERNOON. RAIN WILL COME DOWN HEAVY AT TIMES LATE TUESDAY AFTERNOON AND EVENING AS THE FRONT PUSHES THROUGH THE AREA. WILL LIKELY SEE SOME PROBLEMS OF AREA RIVERS AS ONE TO ONE AND A HALF INCHES OF RAINFALL COMBINES WITH RAPID SNOW MELT AND ICE JAMS ON AREA RIVES. TAIL END OF THE PRECIPITATION WILL LIKELY END AS A BRIEF PERIOD OF WET SNOW OR SLEET AROUND MIDNIGHT TUESDAY NIGHT BUT NOT LOOKING FOR MUCH IF ANY ACCUMULATION. RAIN AND MIXED PRECIP WILL QUICKLY SHIFT EAST OF THE FORECAST AREA AND SKIES WILL CLEAR DOWNWIND OF THE MOUNTAINS BEFORE DAYBREAK. SHOULD BE A MOSTLY SUNNY BUT BREEZY START TO WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE EAST. WINDS WILL QUICKLY DIMINISH TUESDAY AFTERNOON AS TIGHTER GRADIENT SHIFTS EAST AND VARIABLE CLOUDINESS IN THE NORTH WILL ALSO DIMINISH DURING THE AFTERNOON. TEMPERATURES WILL AVERAGE OUT BELOW NORMAL WITH HIGHS RANGING THROUGH THE 30S NORTH AND IN THE LOWER TO MID 40S SOUTH. CLEAR SKIES AND LIGHT WINDS FOR WEDNESDAY NIGHT WILL ALLOW TEMPS TO DROP WELL BELOW NORMAL WITH READINGS DIPPING INTO THE TEENS NORTH AND 20S SOUTH. HIGH PRESSURE WILL SLOWLY SHIFT OFF TO THE EAST THURSDAY AND FRIDAY RESULTING IN TWO FAIRLY NICE DAYS ALONG WITH MODERATING TEMPS. WILL SEE SOME HIGH CLOUDINESS ON FRIDAY BUT BOTH DAYS SHOULD ALSO FEATURE A FAIR AMOUNT OF SUN. EXPECT TEMPS NEAR NORMAL ON THURSDAY WITH HIGHS FROM THE MID 40S TO LOWER 50S. FRIDAY LOOKING SLIGHTLY WARMER WITH HIGHS THROUGHOUT THE REGION IN THE LOWER TO MID 50S...BUT SLIGHTLY COOLER ALONG THE COAST. LOW PRESSURE OVER THE GREAT LAKES WILL DRIVE AN OCCLUDED FRONT TOWARD THE REGION ON SATURDAY. AFTER SOME MORNING SUN CLOUDS WILL BE ON THE INCREASE WITH AFTERNOON SHOWERS PUSHING IN FROM THE WEST. UPPER LOW SWINGING IN FROM THE WEST SATURDAY NIGHT WILL KEEP SHOWER ACTIVITY GOING AND WILL LIKELY BRING ALONG ENOUGH COLDER AIR TO PRODUCE SOME SNOW AT HIGHER ELEVATIONS IN THE NORTH INTO SUNDAY. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... SHORT TERM...COASTAL TERMINAL AND KAUG WILL DROP TO IFR OR LOWER IN LOW STRATUS AND FOG THIS EVENING...AND WILL IMPROVE TO VFR LATE MORNING TO MIDDAY. AT KCON/KLEB/KHIE...WILL SEE SOME FOG AND LOW CLOUDS...PROBABLY REACHING IFR...BUT PROB NOT UNTIL AFTER MIDNIGHT. THEY IMPROVE TO VFR AFTER SUNRISE. AFTER VFR MON AFTERNOON...THE COASTAL TERMINALS LOOK TO FALL TO IFR OR LOWER AGAIN IN STRATUS/FOG AROUND SUNSET...AND THE OTHER TERMINALS WILL FOLLOW SUIT BY MIDNIGHT. LONG TERM...IFR/LIFR CEILINGS/VSBY TUESDAY...IMPROVING TO VFR LATE TUESDAY NIGHT. VFR WEDNESDAY THROUGH FRIDAY. && .MARINE... SHORT TERM...SCA EXTENDED THROUGH MON NIGHT. PERSISTENT SW FLOW WILL PERSIST TONIGHT INTO TUE...AND WILL FRESHEN LATE MONDAY AND MON NIGHT...APPROACHING GALES. LONG TERM...GALES LIKELY TUESDAY THROUGH EARLY WEDNESDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR MEZ007>009-012>014- 018>028. NH...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR NHZ001>010-013-014. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ150>154. && $$ NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
420 AM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ANCHORED OFF THE EAST COAST THROUGH MONDAY. A COLD FRONT WILL GRADUALLY MOVE THROUGH THE REGION LATE MONDAY NIGHT INTO TUESDAY...WITH HIGH PRESSURE BUILDING INTO THE AREA FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... HIPRES IS PARKED OVER THE WRN ATLANTIC. A WARM FRONT IS LOCATED OVER THE NORTHEAST STATES. THE MID-ATLANTIC REGION WILL BE SITUATED DEEP INTO THE WARM/MOIST SECTOR AND IN SLY RETURN FLOW AROUND THE HIGH. SFC DEWPOINTS HAD INCREASED INTO THE 50S OVNGT. 11-3.9U SAT AND SFC OBS AT NAK/NHK CAPTURED THE DEVELOPMENT OF STRATUS ALONG THE WRN SHORE OF THE CHSPK. THE HRRR AND LOCAL ARW- WRF4N MODELS HAVE HAD A DECENT HANDLE ON THE LOW CLOUDS THOUGH APPEAR TO BE TOO AGGRESSIVE WITH LOW VSBYS AND FOG. STRATUS SHOULD BE CONFINED TO THE WRN SHORE AND WILL MIX OUT BY MID MRNG. YDA WAS WARM BUT FCST H8-H9 TEMPS TDA ABOUT 3C WARMER...WHICH SHOULD TRANSLATE TO HIGHS IN THE UPPER 70S AND LOWER 80S ACROSS MUCH OF THE REGION. A BAY BREEZE SHOULD DEVELOP THIS AFTN DUE TO A SIGNIFICANT TEMP/DENSITY GRADIENT INLAND AND OVER THE CHSPK BAY WHERE WATERS TEMPS ARE STILL IN THE 50S. SYNOPTIC SLY WINDS WILL BE STRONG ENOUGH TO PREVENT THE COOL MARINE AIR FROM ADVECTING MUCH INLAND. TRIED TO REFLECT THIS IN FCST TEMP/WIND GRIDS- HIGHS STRUGGLE TO REACH 70F ALONG THE IMMEDIATE WRN SHORE OF MD. LOW- AND MID-LVL SUBSIDENCE UNDER THE RIDGE WILL YIELD DRY CONDITIONS TDA. HIPRES WILL RETREAT FURTHER OFFSHORE TNGT AS A COLD FRONT ADVANCES EWD INTO THE MIDWEST/GREAT LAKES REGIONS TNGT. MOIST SLY WINDS 5-15 MPH WILL PERSIST AFTER SUNSET...KEEPING TEMPS MILD TNGT AND FOG POTENTIAL LOW. FCST MIN TEMPS IN THE UPPER 50S/LOWER 60S FAVORED THE WARMER BIAS CORRECT MET/NAM GUIDANCE. STRATUS MAY DEVELOP AGAIN NEAR THE CHSPK BAY. THE COLD FRONT WILL APPROACH THE WRN SIDE OF THE APPALACHIANS ON MON. HEIGHT FALLS ALOFT AHEAD OF THE AMPLIFY CENTRAL CONUS TROUGH WILL SPREAD EWD TOWARD THE ERN SEABOARD DURING THE DAY AND SLY LLVL JET WILL TRANSPORT MOISTURE INTO THE REGION. HOWEVER...POPS WERE KEPT LOW AND COVERAGE LIMITED TO THE MTS AS THE MAIN SYNOPTIC LIFT REMAINS UPSTREAM OF THE CWA. NOT MUCH INSTABILITY PRESENT ON MON DUE TO THE PRESENCE OF A MID-LVL CAPPING INVERSION. THE MID-LVL SUBSIDENCE INVERSION WEAKENS LATE IN THE DAY ACROSS THE WRN HIGHLANDS...WHERE SLIGHT CHANCE OF TSTMS WERE MENTIONED. TEMPS EXPECTED TO REACH THE MID TO UPPER 70S ACROSS MUCH OF THE AREA DESPITE INCREASING CLOUD COVER. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... MON NIGHT...THE 00Z/03Z ENSEMBLE MODEL GUIDANCE IN GENERALLY GOOD AGREEMENT ON POSITION OF THE APPROACHING COLD FRONT MOVING THROUGH THE GREAT LAKES/OHIO/TENNESSEE VALLEY EARLY IN THE PERIOD. MODELS ARE SLOWER WITH FRONTAL PASSAGE THEN WAS ADVERTIZED YESTERDAY...SO THE CWA WILL STILL BE IN A MILD SOUTHERLY REGIME THIS PERIOD. TUE AND TUE NIGHT...THE COLD FRONT WILL MOVE THROUGH DURING THE DAYTIME. STRONG COLD ADVECTION BEHIND THE FRONT WILL USHER IN MUCH COLDER CONDITIONS. RAIN WILL DEVELOP JUST AHEAD AND ALONG THE FRONT WITH AMOUNTS OF BETWEEN ONE HALF TO ONE INCH CWA WIDE...WITH SOME HIGHER AMOUNTS UP TO ONE AND ONE-HALF INCH POSSIBLE IN CONVECTION. INSTABILITY NOT HIGH OWING TO AMPLE CLOUD COVER...BUT SOME ELEVATED CONVECTION INSTABILITY OF 100-500 J/KG...SO THUNDERSTORMS POSSIBLE. TUE NIGHT...THERE COULD BE LINGERING POST-FRONTAL SHOWERS...AND ALONG AND WEST OF THE BLUE RIDGE...COLD AIR ALOFT COULD MEAN SOME SNOW MIXED IN WITH SHOWERS...BUT NOTHING APPRECIABLE EXPECTED FOR ACCUMULATIONS. 85H TEMPS FALL TO -6C TO -10C RANGE LATE TUE NIGHT. STRONG CAA WILL KEEP NW WINDS && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... WED...HIGH PRESSURE CENTER OVER THE OHIO VALLEY WILL MOVE EAST AND AND BE OVER THE REGION BY THE END OF WED. TEMPERATURES ON WED WILL BE UNSEASONABLY COOL BY A GOOD 10 TO 15 DEGF WITH BLUSTRY WINDS TO START THE DAY...GRADUALLY DIMINISHING BY LATE AFTERNOON. THU-FRI...HIGH PRESSURE WILL MOVE NORTHEAST AND FORM A RIDGE ALONG THE EASTERN SEABOARD BRINGING DRY WEATHER AND NORTH TO NORTHEAST WINDS. COOL TEMPS EXPECTED THUR...ALTHOUGH NOT QUITE AS COOL AS WED. TEMPS MODERATE A BIT MORE ON FRI. SAT...LOTS OF UNCERTAINTY AS WE HEAD TOWARD THE WEEKEND. RIGHT NOW IT LOOKS DRY FOR SAT...BUT VARIOUS MODEL SOLNS ARE SHOWING LOW PRESSURE SOMEWHERE OF THE EASTERN SEABOARD...OR GREAT LAKES... DEPENDING ON WHAT MODEL GUIDANCE ONE LOOKS AT. FOR NOW WILL DOWNPLAY PRECIP CHANCES AS UNCERTAINTY IS HIGH. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... LOW CLOUDS HAVE DEVELOPED OVNGT ALONG THE WRN SHORE OF THE MD CHSPK BAY...RESULTING IN MVFR CIGS AT MTN. CIGS MAY LOWER TO IFR TOWARD DAYBREAK AT MTN AND TO MVFR AT BWI. TERMINALS FARTHER WEST WILL NOT BE IMPACTED BY ERY MRNG STRATUS. VFR TDA AND THIS EVE ACROSS ALL TERMINALS. SLY WINDS WILL GUST AROUND 20 KT THIS AFTN. STRATUS MAY DEVELOP ERY MON MRNG AGAIN NEAR THE BAY. VFR ON MON WITH SLY WINDS 15-25 KT. MON NIGHT VFR CONDITIONS INITIALLY...WITH LOWERING CIGS TO MVFR DURING THE OVERNIGHT. ON TUE...IFR CIGS AND VSBYS IN AREAS OF RAIN ALONG AND AHEAD OF THE FRONT...WITH BRIEF PDS OF TSTMS POSSIBLE. FRONT MOVES THROUGH TUE AFTERNOON...WITH CONDITIONS VFR EXPECTED LATE TUE THROUGH THE END OF THE WEEK. NW WINDS 15 TO 20 KT WITH GUSTS TO 25 KT LATE TUE NIGHT AND WED MORNING. && .MARINE... SLY WINDS HAD DIMINISHED OVNGT TO UNDER 15 KT. WINDS WILL INCREASE THIS AFTN AS MIXING DEEPENS. SCA IN EFFECT FOR ALL OF THE WATERS THIS AFTN...TNGT AND NOW MON WITH SLY WINDS 20-25 KT. HOWEVER... WINDS MAY RELAX BRIEFLY LATE TNGT OUTSIDE OF THOSE MARINE LOCATIONS EXPOSED TO SLY CHANNELING. SCA LEVEL WINDS ARE EXPECTED MON NIGHT THROUGH WED. NEAR GALE FORCE WIND GUSTS POSSIBLE LATE TUE EVENING AND EARLY WED MORNING ON THE LOWER BAY AND LOWER TIDAL POTOMAC. WINDS DIMINISH BELOW SCA LEVELS BY LATE WED. THEN SMALL CRAFT ADVISORY LEVEL CONDITIONS ARE NOT LIKELY AGAIN THROUGH THE END OF THE WEEK. && .TIDES/COASTAL FLOODING... NEGATIVE TIDAL ANOMALIES DECREASED LAST NGT AND ARE NOW NEAR ASTRONOMICAL NORM AS A RESULT OF SLY FLOW. EXPECT THIS TREND TO CONTINUE...LEADING TO POSITIVE ANOMALIES BETWEEN ONE-HALF AND ONE FOOT BY TNGT AND MON. CBOFS KEEPS ALL WRN SHORE FCST POINTS BELOW MINOR COASTAL FLOOD THRESHOLD THRU TNGT. WITH THE SOUTHERLY FLOW EXPECTED TO PERSIST THRU MONDAY NIGHT AND A FULL MOON UPCOMING... WATER LEVELS COULD APPROACH MINOR FLOOD CRITERIA AT THE MORE SENSITIVE LOCATIONS MONDAY AND MONDAY NGT. WILL ADD MENTION TO THE HWO. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 PM EDT MONDAY FOR ANZ530>543. && $$ SYNOPSIS...JRK NEAR TERM...JRK SHORT TERM...SMZ LONG TERM...SMZ AVIATION...JRK/SMZ MARINE...JRK/SMZ TIDES/COASTAL FLOODING...JRK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
326 PM EDT SUN APR 13 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 508 AM EDT SUN APR 13 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH NEAR THE WEST COAST WITH A DOWNSTREAM TROUGH FROM CNTRL CANADA INTO THE SW CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE NRN GREAT LAKES. A SHRTWV INTO SW WI NORTH OF A FRONTAL BOUNDARY FROM SW IA INTO NRN IL AND SRN LOWER MI...AND IN AN AREA OF STRONG LOW LEVEL MOISUTR INFLOW...SUPPORTED AN AREA OF TSRA OVER SE WI INTO SRN LAKE MICHIGAN. ANOTHER SIGNIFICANT SHRTWV WAS LIFTING FROM ERN CO/NM TOWARD THE CNTRL PLAINS. OTHERWISE...ONLY SOME PATCHY DRIZZLE AND AREAS OF FOG PREVAILED OVER UPPER MI AS MID LEVEL DRYING ABOVE 850 MB HAS SPREAD OVER THE AREA. TODAY...EXCEPT FOR THE LINGERING FOG EARLY...ESPECIALLY OVER THE E TO NE UPSLOPE FLOW AREAS IN CNTRL UPPER MI...QUIET WEATHER IS EXPECTED AS THE MAIN PCPN AREA WILL REMAIN CLOSER TO THE SFC FRONT NEAR THE IL/W BORDER. NRLY WINDS AND CLOUDS WILL KEEP TEMPS NEAR THE LOWER END OF GUIDANCE...IN THE LOWER 40S NORTH TO THE UPPER 40S SOUTH. TONIGHT...AS THE CNTRL PLAINS SHRTWV MOVES TOWARD THE GREAT LAKES AND UPPER LEVEL DIV ASSOCIATED WITH THE RIGHT ENTRANCE OF THE 130-140KT JET OVER NRN ONTARIO INCREASES...PCPN WILL EXPAND FROM FROM NRN WI INTO THE SE HALF OF UPPER MI. THE MODELS SHOW SIGNFICANT DIFFERENCES WITH HOW FAR TO THE NW THE HEAVIER PCPN SPREADS. THE NAM WITH THE STRONGEST 700-600 MB FGEN FCSTS HIGHER QPF AMOUNTS TO AROUND 0.50 INCH INTO CNTRL UPPER MI. THE REGIONAL-GEM...ECMWF AND GFS KEEP THE HEAVIER PCPN FARTHER TO THE SOUTHEAST. EVEN THOUGH THE STRONGER MID LEVEL DYNAMICS MAY BE POSSIBLE...SUSPECT THAT THE MOISTURE INFLOW TO THE NW PORTION OF THE PCPN SHIELD WILL BE LIMITED BY CONVECTION AND HEAVY RAIN CLOSER TO THE 850 MB FRONT. NEVERTHELESS QPF AMOUNTS OF 0.20 TO 0.40 INCH EAST OF A LINE FROM IMT-P53 COULD SUPPORT WET SNOW ACCUMULATIONS OF A FEW INCHES S COLDER AIR FILTERS INTO THE AREA BRINGING A CHANGEOVER FROM RAIN TO SNOW BY LATE EVENING. AS TEMPS FALL AT OR BELOW 30F CNTRL...SOME SLIPPERY AREA MAY DEVELOP ON UNTREATED ROADS. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 326 PM EDT SUN APR 13 2014 FOCUSED MAINLY ON MID WEEK AS POTENTIAL EXISTS FOR SIGNIFICANT PRECIP. FOR LATER THIS WEEK INTO THE WEEKEND...CONFIDENCE IS REDUCED SIGNIFICANT...SO JUST USED CONSENSUS GUIDANCE FOR THAT TIME PERIOD. SOME ISOLATED-SCATTERED LES IS EXPECTED ON MON NIGHT/TUE AS 850MB TEMPS WILL BE -18C TO -20C WITH NW LOW LEVEL WINDS. INCOMING SFC HIGH PRESSURE WILL LEAD TO A GRADUAL DIMINISHING TREND THROUGH THE PERIOD. WHILE CONFIDENCE IS STILL LIMITED...THE MAIN ATTENTION IN THE LONG TERM WITH THE RESULT OF UPPER LEVEL ENERGY MOVING INTO THE PLAINS TUE NIGHT. BASICALLY...THERE ARE TWO CAMPS THE MODELS ARE IN. THE 12Z/13 GFS 12Z/13 AND GLOBAL GEM PHASE AN UPPER LEVEL TROUGH WITH A SHORTWAVE AS THE TROUGH NEARS THE US/CANADIAN BORDER...WHICH DEEPENS THE TROUGH INTO A CLOSED LOW BY THURSDAY AFTERNOON AND DIRECTS A SECOND SHORTWAVE INTO THE SRN PLAINS. AS A RESULT...THE SFC LOW ASSOCIATED WITH THE SECOND SHORTWAVE DEEPENS AND MOVES TO THE SRN PLAINS...WITH A SFC TROUGH/FRONT DEVELOPING OVER THE CWA THAT REMAINS STATIONARY OVER THE CWA WED THROUGH AT LEAST THU AHEAD OF THE UPPER LOW. THIS IDEA RESULTS IN TOTAL QPF AMOUNTS TUE NIGHT THROUGH THU GENERALLY OF 1-2 INCHES /EVEN BLEND OF THE GEM AND GFS/. THE 00Z/13 ECMWF DOES NOT PHASE THE TROUGH AND FIRST SHORTWAVE...WHICH BRINGS THAT SHORTWAVE AND WEAK SFC LOW S OF THE CWA WED INTO WED NIGHT...WITH MUCH LOWER QPF AMOUNTS ON THE N SIDE OF THE SFC LOW OF UP TO 0.6 INCHES OVER THE NRN CWA. MODELS DO SHOW SIMILAR THERMAL PROFILES THROUGH THIS TIME FRAME...WHICH WOULD SUPPORT A MIX OF RAIN AND SNOW S AND MOSTLY SNOW N. AS FOR MODEL CONTINUITY...THE GFS HAS SHOWN GOOD RUN TO RUN CONTINUITY OVER THE LAST SEVERAL RUNS. THE ECMWF DID SHOW GOOD CONTINUITY UNTIL THE LAST RUN...WHICH TRENDED A LITTLE CLOSER THE GFS. THE GLOBAL GEM HAS BEEN TRENDING TOWARD THE GFS. THIS BEING SAID...STILL HAVE LIMITED CONFIDENCE AS THE HIGHER END QPF AMOUNTS FROM THE GFS/GEM WILL BE VERY DEPENDENT ON MANY OTHER FEATURES...AND FORECASTING MORE ANOMALOUSLY HIGH QPF AMOUNTS IS HARD TO JUSTIFY WITHOUT BETTER CONFIDENCE. USED A CONSENSUS APPROACH WITH A BIAS TOWARD THE GFS/GEM. WILL MENTION IN THE HWO/EHWO THE POTENTIAL FOR MODERATE SNOWFALL AMOUNTS SOMEWHERE IN THE CWA. ON THE HIGH EXTREME FOR QPF...THERE IS POTENTIAL FOR SIGNIFICANT SNOWFALL...BUT /AS MENTIONED PREVIOUSLY/ WILL JUST MENTION MODERATE AMOUNTS FOR NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 112 PM EDT SUN APR 13 2014 MVFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT IWD WITH UPSLOPE FLOW OFF OF LAKE SUPERIOR. CONDITIONS WILL SLOWLY IMPROVE TO MVFR THIS AFTERNOON AT CMX AS DRIER AIR SLOWLY WORKS INTO THE AREA. A SFC LOW IS FCST TO MOVE FROM THE PLAINS INTO THE GREAT LAKES TONIGHT AND SAW WILL BE IN THE LOCATION OF THE NW EDGE OF THE ACCOMPANYING PCPN AREA AND EXPECT A RETURN OF SOME SN/IFR/LIFR CONDITIONS THIS EVENING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 429 AM EDT SUN APR 13 2014 NORTH TO NORTHWEST GALE FORCE GUSTS TO 35 KNOTS EXPECTED ON MONDAY IN WAKE OF LOW PRESSURE SYSTEM LIFTING ACROSS SOUTHERN QUEBEC. PRESSURE GRADIENT WEAKENS BY MONDAY NIGHT TO RESULT IN WINDS LESS THAN 25 KNOTS BY THAT TIME. WINDS CURRENTLY FORECAST TO STAY MAINLY BLO 20 KNOTS REST OF THE WEEK...BUT THIS DEPENDS ON WHETHER ONE OR TWO LOW PRESSURE SYSTEMS IMPACT THE UPPER GREAT LAKES. THE TWO TIME FRAMES OF INTEREST WOULD BE WEDNESDAY AND WEDNESDAY NIGHT AND AGAIN ON FRIDAY. IF EITHER OF THESE LOW PRESSURE SYSTEMS DO OCCUR...THEN WINDS MAY END UP STRONGER THAN CURRENT FORECAST SHOWS. && .HYDROLOGY... ISSUED AT 326 PM EDT SUN APR 13 2014 WITH COOLER TEMPERATURES YESTERDAY AND MUCH COOLER TEMPERATURES TODAY INTO EARLY THIS WEEK...SNOWMELT HAS SLOWED SIGNIFICANTLY AND MAY STOP ALTOGETHER OVER THE COMING FEW DAYS. GIVEN ADDITIONAL OPPORTUNITIES FOR PRECIPITATION THIS WEEK AND WITH 4-9 INCHES OF SNOW WATER EQUIVALENT STILL OVER PARTS OF WESTERN AND CENTRAL UPPER MICHIGAN...THERE WILL BE PLENTY OF WATER AVAILABLE FOR THE SECOND PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS. APPEARS THE WARMER TEMPS WHICH COULD START UP THE NEXT PERIOD OF SNOWMELT/RUNOFF BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM 2 AM TO 2 PM EDT MONDAY FOR MIZ006- 007-085. LAKE SUPERIOR... GALE WARNING FROM 8 AM TO 5 PM EDT MONDAY FOR LSZ266-267. GALE WARNING FROM 8 AM TO 2 PM EDT MONDAY FOR LSZ244-245-264-265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLA HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
113 PM EDT SUN APR 13 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 508 AM EDT SUN APR 13 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH NEAR THE WEST COAST WITH A DOWNSTREAM TROUGH FROM CNTRL CANADA INTO THE SW CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE NRN GREAT LAKES. A SHRTWV INTO SW WI NORTH OF A FRONTAL BOUNDARY FROM SW IA INTO NRN IL AND SRN LOWER MI...AND IN AN AREA OF STRONG LOW LEVEL MOISUTR INFLOW...SUPPORTED AN AREA OF TSRA OVER SE WI INTO SRN LAKE MICHIGAN. ANOTHER SIGNIFICANT SHRTWV WAS LIFTING FROM ERN CO/NM TOWARD THE CNTRL PLAINS. OTHERWISE...ONLY SOME PATCHY DRIZZLE AND AREAS OF FOG PREVAILED OVER UPPER MI AS MID LEVEL DRYING ABOVE 850 MB HAS SPREAD OVER THE AREA. TODAY...EXCEPT FOR THE LINGERING FOG EARLY...ESPECIALLY OVER THE E TO NE UPSLOPE FLOW AREAS IN CNTRL UPPER MI...QUIET WEATHER IS EXPECTED AS THE MAIN PCPN AREA WILL REMAIN CLOSER TO THE SFC FRONT NEAR THE IL/W BORDER. NRLY WINDS AND CLOUDS WILL KEEP TEMPS NEAR THE LOWER END OF GUIDANCE...IN THE LOWER 40S NORTH TO THE UPPER 40S SOUTH. TONIGHT...AS THE CNTRL PLAINS SHRTWV MOVES TOWARD THE GREAT LAKES AND UPPER LEVEL DIV ASSOCIATED WITH THE RIGHT ENTRANCE OF THE 130-140KT JET OVER NRN ONTARIO INCREASES...PCPN WILL EXPAND FROM FROM NRN WI INTO THE SE HALF OF UPPER MI. THE MODELS SHOW SIGNFICANT DIFFERENCES WITH HOW FAR TO THE NW THE HEAVIER PCPN SPREADS. THE NAM WITH THE STRONGEST 700-600 MB FGEN FCSTS HIGHER QPF AMOUNTS TO AROUND 0.50 INCH INTO CNTRL UPPER MI. THE REGIONAL-GEM...ECMWF AND GFS KEEP THE HEAVIER PCPN FARTHER TO THE SOUTHEAST. EVEN THOUGH THE STRONGER MID LEVEL DYNAMICS MAY BE POSSIBLE...SUSPECT THAT THE MOISTURE INFLOW TO THE NW PORTION OF THE PCPN SHIELD WILL BE LIMITED BY CONVECTION AND HEAVY RAIN CLOSER TO THE 850 MB FRONT. NEVERTHELESS QPF AMOUNTS OF 0.20 TO 0.40 INCH EAST OF A LINE FROM IMT-P53 COULD SUPPORT WET SNOW ACCUMULATIONS OF A FEW INCHES S COLDER AIR FILTERS INTO THE AREA BRINGING A CHANGEOVER FROM RAIN TO SNOW BY LATE EVENING. AS TEMPS FALL AT OR BELOW 30F CNTRL...SOME SLIPPERY AREA MAY DEVELOP ON UNTREATED ROADS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 429 AM EDT SUN APR 13 2014 MOST OF THE IMPACTS FROM THE SYSTEM MOVING ACROSS THE UPPER GREAT LAKES OCCUR JUST PRECEEDING THE LONG TERM. KEPT HIGHER LIKELY POPS OVER EAST THROUGH 18Z ON MONDAY AS LAST PUSH OF DIVERGENCE ALOFT AND LINGERING DEEP MOISTURE MAY GENERATE UP TO 0.10 INCH OF LIQUID PRECIP IN THE FORM OF AROUND 1 INCH OF WET SNOW. AWAY FM THIS AREA OF SNOW...HAVE JUST SOME SMALL CHANCES DUE TO UPSLOPE AND SOME MOISTURE OFF THE GAPS IN WESTERN LK SUPERIOR. DEEP MOISTURE WILL BE WELL TO THE EAST AND OVERALL WILL BE SEEING LARGER SCALE SUBSIDENCE OVER MUCH OF CWA BY LATE MONDAY MORNING...SO PROBABLY LOOKING AT FLURRIES OR VERY LIGHT SNOW SHOWERS. UNSEASONABLY DEEP TROUGHING WILL SETTLE OVER THE UPPER GREAT LAKES THE FIRST PART OF THE WEEK. QUITE COOL...WITH H85 TEMPS DOWN TO -18C ON TUESDAY IN THE AXIS OF THE TROUGHING. EVEN WITH GAPS OF OPEN WATER OVER ESPECIALLY WEST HALF OF LK SUPERIOR...DO NOT EXPECT MUCH IN WAY OF LAKE EFFECT LATER MONDAY THROUGH TUESDAY AS AIR IS DRY IN THE LARGER SCALE. SOUNDINGS FM GFS INDICATE AN INVERTED-V LOOK...WITH DRY SUB-CLOUD LAYER UP TO THE THIN MOIST LAYER AROUND H85. BECOMES SLIGHTLY MORE MOIST ON MONDAY NIGHT WITH NIGHTTIME COOLING...BUT EVEN THIS AFFECT SHOULD BE MINIMAL AS LARGER SCALE LOW-LEVELS ARE DOMINATED BY ANTICYCLONIC FLOW. MOST NOTEABLE WILL BE THE COLD...WITH DAYTIME TEMPS ON MONDAY FALLING TO THE UPR TEENS OR LOWER 20S BY LATE AFTN NEAR LK SUPERIOR AND WITH DAYTIME HIGHS ON TUESDAY STRUGGLING TO REACH 32 DEGREES...EVEN OVER SCNTRL. NORMAL HIGHS ON TUESDAY ARE IN THE UPPER 40S NEAR LK SUPERIOR AND INTO THE LOWER 50S NEAR THE WISCONSIN BORDER. DESPITE INCREASING SUNSHINE BY AFTERNOON...READINGS ON TUESDAY WILL END UP 20-25 DEGREES BELOW NORMAL. COOL TEMPS FOR THE NIGHTS AS WELL. MAINLY TEENS EXPECTED BOTH MONDAY NIGHT AND TUESDAY NIGHT...BUT SINGLE DIGITS POSSIBLE AT ANY INTERIOR LOCATION ON MONDAY NIGHT THAT CLEARS OUT BRIEFLY AND ALSO OVER THE EASTERN INTERIOR TUESDAY NIGHT. LATER TUESDAY NIGHT BUT MORE SO INTO WEDNESDAY AND WEDNESDAY NIGHT...GFS STILL SHOWING WIDESPREAD MODERATE QPF WHICH WOULD BE IN THE FORM OF SNOW. GFS HAS SHOWN THIS OVER ITS LAST 5 RUNS BACK TO 00Z ON 12 APRIL. ECMWF RATHER INSISTENT INDICATING WIDESPREAD QPF WILL BE MORE FROM DAKOTAS ACROSS MINNESOTA AND ACROSS FAR WESTERN CWA TO LK SUPERIOR. GFS IDEA IS MORE OR LESS SUPPORTED BY LAST COUPLE GEM-NH RUNS AND 12Z/12 APRIL RUN OF UKMET. DIVING IN MORE IT APPEARS THAT ALTHOUGH THE GFS AND ECMWF IDEAS LOOK SIMILAR IN THE LARGER SCALE /LEAD SHORTWAVE INITIALIZING SFC LOW OVER NORTHERN PLAINS WHILE STRONGER/LARGER SHORTWAVE TROUGH DROPS ACROSS SOUTH CENTRAL CANADA/ THEY DIFFER IN HOW MUCH PHASING OCCURS BTWN THE TWO UPPER LEVEL FEATURES. GFS IS SLOWER TO PHASE THUS BRINGS SFC LOW FARTHER EAST INITIALLY WHILE THE ECMWF PHASES QUICKER AND LIFTS THE LOW MORE NORTHEAST OVER WESTERN UPR MICHIGAN. LEAD SHORTWAVE WILL EMERGE OUT OF STRONG SHORTWAVE TROUGH CURRENTLY SHOWING UP WELL ON WV LOOP OVER THE GULF OF ALASKA. A CONSENSUS OF PRIMARY MODELS INDICATES HIGH CHANCES OVER CWA...BEGINNING VERY LATE TUESDAY NIGHT OVER THE FAR WEST...SPREADING ACROSS ALL CWA ON WEDNESDAY...AND LINGERING INTO THURSDAY MORNING MAINLY EASTERN CWA. PTYPE MAINLY SNOW...THOUGH ENOUGH LOW-LEVEL WARMING OCCURS OVER SCNTRL BY WEDNESDAY NIGHT TO RESULT IN MIX OF RAIN/SNOW. MODERATE SNOW AMOUNTS POSSIBLE...ESPECIALLY NORTH AND WEST CWA PER BLEND OF LATEST GFS/ECMWF/GEM-NH. MIXING RATIOS 2.5-3 G/KG INDICATE MODERATE SNOW AMOUNTS AS WELL WEDNESDAY AND WEDNESDAY NIGHT. 00Z RUN OF ECMWF HAS TRENDED CLOSER TO GFS/GEM-NH IDEAS. WILL LEAVE MENTION OF THIS SYSTEM OUT OF HWOMQT NOW THOUGH SINCE AS THIS IS THE FIRST ECMWF RUN TO SHOW SIMILAR SOLUTION TO GFS WITH THIS SYSTEM. UNCERTAINTY ONLY INCREASES BY FRIDAY AS RECENT RUNS OF GFS BRING ANOTHER SHORTWAVE TROUGH AND WRAPPED UP LOW PRESSURE SYSTEM WITH TOWARD 1 INCH OF QPF ACROSS UPPER LAKES. ECMWF NOT IN AGREEMENT AT ALL WHILE THE GEM-NH SHOWS SOME IDEA THERE COULD BE SOME PRECIP... JUST NOT AS STRONG AS GFS. CONSENSUS...WHICH IS WEIGHTED TOWARD GFS INPUT... GIVES ANOTHER ROUND OF CHANCE POPS FOR FRIDAY. MANUALLY TWEAKED THOSE DOWN SLIGHTLY...BUT LEFT ALONE OTHERWISE. CRITICAL THICKNESSES AND FORECASTED TEMPS INDICATE RAIN OR SNOW IS POSSIBLE. TEMPS FRIDAY AND INTO SATURDAY WILL BE HIGHLY DEPENDANT ON WHETHER ANY SYSTEM IS IN THE VCNTY. IF SO...TEMPS WILL PROBABLY STAY IN THE 30S WITH THE CLOUDS AND PRECIPITATION. IF NOT...INLAND AREAS AWAY FM THE LAKES COULD REACH LOWER 50S ONE OR BOTH OF THESE DAYS AS H85 TEMPS ARE WITHIN A FEW DEGREES OF 0C. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 112 PM EDT SUN APR 13 2014 MVFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT IWD WITH UPSLOPE FLOW OFF OF LAKE SUPERIOR. CONDITIONS WILL SLOWLY IMPROVE TO MVFR THIS AFTERNOON AT CMX AS DRIER AIR SLOWLY WORKS INTO THE AREA. A SFC LOW IS FCST TO MOVE FROM THE PLAINS INTO THE GREAT LAKES TONIGHT AND SAW WILL BE IN THE LOCATION OF THE NW EDGE OF THE ACCOMPANYING PCPN AREA AND EXPECT A RETURN OF SOME SN/IFR/LIFR CONDITIONS THIS EVENING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 429 AM EDT SUN APR 13 2014 NORTH TO NORTHWEST GALE FORCE GUSTS TO 35 KNOTS EXPECTED ON MONDAY IN WAKE OF LOW PRESSURE SYSTEM LIFTING ACROSS SOUTHERN QUEBEC. PRESSURE GRADIENT WEAKENS BY MONDAY NIGHT TO RESULT IN WINDS LESS THAN 25 KNOTS BY THAT TIME. WINDS CURRENTLY FORECAST TO STAY MAINLY BLO 20 KNOTS REST OF THE WEEK...BUT THIS DEPENDS ON WHETHER ONE OR TWO LOW PRESSURE SYSTEMS IMPACT THE UPPER GREAT LAKES. THE TWO TIME FRAMES OF INTEREST WOULD BE WEDNESDAY AND WEDNESDAY NIGHT AND AGAIN ON FRIDAY. IF EITHER OF THESE LOW PRESSURE SYSTEMS DO OCCUR...THEN WINDS MAY END UP STRONGER THAN CURRENT FORECAST SHOWS. && .HYDROLOGY... ISSUED AT 429 AM EDT SUN APR 13 2014 RIVER HYDROGRAPHS INDICATE THAT ICE JAMS AT RKLM4/FRDM4 AND EVEN AT MSQM4 OVER THE LAST FEW DAYS HAVE BROKEN AND RIVERS HAVE LEVELED OFF. AS OF THIS MORNING...NO IMPACTS HAVE BEEN REPORTED FROM THE ICE JAMS. SEEMS THAT WITH THE COOLER TEMPS SEEN ON SATURDAY AND THE COOLER TEMPS EXPECTED FOR MUCH OF THE UPCOMING WEEK /HIGHS 20S TO 30S WITH LOWS WELL BLO FREEZING THROUGH AT LEAST WEDNESDAY/...WE HAVE PROBABLY REACHED THE END OF THIS INITIAL PERIOD OF SNOWMELT/RUNOFF. GIVEN ADDITIONAL OPPORTUNITIES FOR PRECIPITATION THIS WEEK AND WITH 4-9 INCHES OF SNOW WATER EQUIVALENT STILL OVER PARTS OF WESTERN AND CENTRAL UPPER MICHIGAN...THERE WILL BE PLENTY OF WATER AVAILABLE FOR THE SECOND PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS. APPEARS THAT WARMER TEMPS WHICH COULD START UP THE NEXT PERIOD OF SNOWMELT/RUNOFF WILL RETURN BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
738 AM EDT SUN APR 13 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 508 AM EDT SUN APR 13 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH NEAR THE WEST COAST WITH A DOWNSTREAM TROUGH FROM CNTRL CANADA INTO THE SW CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE NRN GREAT LAKES. A SHRTWV INTO SW WI NORTH OF A FRONTAL BOUNDARY FROM SW IA INTO NRN IL AND SRN LOWER MI...AND IN AN AREA OF STRONG LOW LEVEL MOISUTR INFLOW...SUPPORTED AN AREA OF TSRA OVER SE WI INTO SRN LAKE MICHIGAN. ANOTHER SIGNIFICANT SHRTWV WAS LIFTING FROM ERN CO/NM TOWARD THE CNTRL PLAINS. OTHERWISE...ONLY SOME PATCHY DRIZZLE AND AREAS OF FOG PREVAILED OVER UPPER MI AS MID LEVEL DRYING ABOVE 850 MB HAS SPREAD OVER THE AREA. TODAY...EXCEPT FOR THE LINGERING FOG EARLY...ESPECIALLY OVER THE E TO NE UPSLOPE FLOW AREAS IN CNTRL UPPER MI...QUIET WEATHER IS EXPECTED AS THE MAIN PCPN AREA WILL REMAIN CLOSER TO THE SFC FRONT NEAR THE IL/W BORDER. NRLY WINDS AND CLOUDS WILL KEEP TEMPS NEAR THE LOWER END OF GUIDANCE...IN THE LOWER 40S NORTH TO THE UPPER 40S SOUTH. TONIGHT...AS THE CNTRL PLAINS SHRTWV MOVES TOWARD THE GREAT LAKES AND UPPER LEVEL DIV ASSOCIATED WITH THE RIGHT ENTRANCE OF THE 130-140KT JET OVER NRN ONTARIO INCREASES...PCPN WILL EXPAND FROM FROM NRN WI INTO THE SE HALF OF UPPER MI. THE MODELS SHOW SIGNFICANT DIFFERENCES WITH HOW FAR TO THE NW THE HEAVIER PCPN SPREADS. THE NAM WITH THE STRONGEST 700-600 MB FGEN FCSTS HIGHER QPF AMOUNTS TO AROUND 0.50 INCH INTO CNTRL UPPER MI. THE REGIONAL-GEM...ECMWF AND GFS KEEP THE HEAVIER PCPN FARTHER TO THE SOUTHEAST. EVEN THOUGH THE STRONGER MID LEVEL DYNAMICS MAY BE POSSIBLE...SUSPECT THAT THE MOISTURE INFLOW TO THE NW PORTION OF THE PCPN SHIELD WILL BE LIMITED BY CONVECTION AND HEAVY RAIN CLOSER TO THE 850 MB FRONT. NEVERTHELESS QPF AMOUNTS OF 0.20 TO 0.40 INCH EAST OF A LINE FROM IMT-P53 COULD SUPPORT WET SNOW ACCUMULATIONS OF A FEW INCHES S COLDER AIR FILTERS INTO THE AREA BRINGING A CHANGEOVER FROM RAIN TO SNOW BY LATE EVENING. AS TEMPS FALL AT OR BELOW 30F CNTRL...SOME SLIPPERY AREA MAY DEVELOP ON UNTREATED ROADS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 429 AM EDT SUN APR 13 2014 MOST OF THE IMPACTS FROM THE SYSTEM MOVING ACROSS THE UPPER GREAT LAKES OCCUR JUST PRECEEDING THE LONG TERM. KEPT HIGHER LIKELY POPS OVER EAST THROUGH 18Z ON MONDAY AS LAST PUSH OF DIVERGENCE ALOFT AND LINGERING DEEP MOISTURE MAY GENERATE UP TO 0.10 INCH OF LIQUID PRECIP IN THE FORM OF AROUND 1 INCH OF WET SNOW. AWAY FM THIS AREA OF SNOW...HAVE JUST SOME SMALL CHANCES DUE TO UPSLOPE AND SOME MOISTURE OFF THE GAPS IN WESTERN LK SUPERIOR. DEEP MOISTURE WILL BE WELL TO THE EAST AND OVERALL WILL BE SEEING LARGER SCALE SUBSIDENCE OVER MUCH OF CWA BY LATE MONDAY MORNING...SO PROBABLY LOOKING AT FLURRIES OR VERY LIGHT SNOW SHOWERS. UNSEASONABLY DEEP TROUGHING WILL SETTLE OVER THE UPPER GREAT LAKES THE FIRST PART OF THE WEEK. QUITE COOL...WITH H85 TEMPS DOWN TO -18C ON TUESDAY IN THE AXIS OF THE TROUGHING. EVEN WITH GAPS OF OPEN WATER OVER ESPECIALLY WEST HALF OF LK SUPERIOR...DO NOT EXPECT MUCH IN WAY OF LAKE EFFECT LATER MONDAY THROUGH TUESDAY AS AIR IS DRY IN THE LARGER SCALE. SOUNDINGS FM GFS INDICATE AN INVERTED-V LOOK...WITH DRY SUB-CLOUD LAYER UP TO THE THIN MOIST LAYER AROUND H85. BECOMES SLIGHTLY MORE MOIST ON MONDAY NIGHT WITH NIGHTTIME COOLING...BUT EVEN THIS AFFECT SHOULD BE MINIMAL AS LARGER SCALE LOW-LEVELS ARE DOMINATED BY ANTICYCLONIC FLOW. MOST NOTEABLE WILL BE THE COLD...WITH DAYTIME TEMPS ON MONDAY FALLING TO THE UPR TEENS OR LOWER 20S BY LATE AFTN NEAR LK SUPERIOR AND WITH DAYTIME HIGHS ON TUESDAY STRUGGLING TO REACH 32 DEGREES...EVEN OVER SCNTRL. NORMAL HIGHS ON TUESDAY ARE IN THE UPPER 40S NEAR LK SUPERIOR AND INTO THE LOWER 50S NEAR THE WISCONSIN BORDER. DESPITE INCREASING SUNSHINE BY AFTERNOON...READINGS ON TUESDAY WILL END UP 20-25 DEGREES BELOW NORMAL. COOL TEMPS FOR THE NIGHTS AS WELL. MAINLY TEENS EXPECTED BOTH MONDAY NIGHT AND TUESDAY NIGHT...BUT SINGLE DIGITS POSSIBLE AT ANY INTERIOR LOCATION ON MONDAY NIGHT THAT CLEARS OUT BRIEFLY AND ALSO OVER THE EASTERN INTERIOR TUESDAY NIGHT. LATER TUESDAY NIGHT BUT MORE SO INTO WEDNESDAY AND WEDNESDAY NIGHT...GFS STILL SHOWING WIDESPREAD MODERATE QPF WHICH WOULD BE IN THE FORM OF SNOW. GFS HAS SHOWN THIS OVER ITS LAST 5 RUNS BACK TO 00Z ON 12 APRIL. ECMWF RATHER INSISTENT INDICATING WIDESPREAD QPF WILL BE MORE FROM DAKOTAS ACROSS MINNESOTA AND ACROSS FAR WESTERN CWA TO LK SUPERIOR. GFS IDEA IS MORE OR LESS SUPPORTED BY LAST COUPLE GEM-NH RUNS AND 12Z/12 APRIL RUN OF UKMET. DIVING IN MORE IT APPEARS THAT ALTHOUGH THE GFS AND ECMWF IDEAS LOOK SIMILAR IN THE LARGER SCALE /LEAD SHORTWAVE INITIALIZING SFC LOW OVER NORTHERN PLAINS WHILE STRONGER/LARGER SHORTWAVE TROUGH DROPS ACROSS SOUTH CENTRAL CANADA/ THEY DIFFER IN HOW MUCH PHASING OCCURS BTWN THE TWO UPPER LEVEL FEATURES. GFS IS SLOWER TO PHASE THUS BRINGS SFC LOW FARTHER EAST INITIALLY WHILE THE ECMWF PHASES QUICKER AND LIFTS THE LOW MORE NORTHEAST OVER WESTERN UPR MICHIGAN. LEAD SHORTWAVE WILL EMERGE OUT OF STRONG SHORTWAVE TROUGH CURRENTLY SHOWING UP WELL ON WV LOOP OVER THE GULF OF ALASKA. A CONSENSUS OF PRIMARY MODELS INDICATES HIGH CHANCES OVER CWA...BEGINNING VERY LATE TUESDAY NIGHT OVER THE FAR WEST...SPREADING ACROSS ALL CWA ON WEDNESDAY...AND LINGERING INTO THURSDAY MORNING MAINLY EASTERN CWA. PTYPE MAINLY SNOW...THOUGH ENOUGH LOW-LEVEL WARMING OCCURS OVER SCNTRL BY WEDNESDAY NIGHT TO RESULT IN MIX OF RAIN/SNOW. MODERATE SNOW AMOUNTS POSSIBLE...ESPECIALLY NORTH AND WEST CWA PER BLEND OF LATEST GFS/ECMWF/GEM-NH. MIXING RATIOS 2.5-3 G/KG INDICATE MODERATE SNOW AMOUNTS AS WELL WEDNESDAY AND WEDNESDAY NIGHT. 00Z RUN OF ECMWF HAS TRENDED CLOSER TO GFS/GEM-NH IDEAS. WILL LEAVE MENTION OF THIS SYSTEM OUT OF HWOMQT NOW THOUGH SINCE AS THIS IS THE FIRST ECMWF RUN TO SHOW SIMILAR SOLUTION TO GFS WITH THIS SYSTEM. UNCERTAINTY ONLY INCREASES BY FRIDAY AS RECENT RUNS OF GFS BRING ANOTHER SHORTWAVE TROUGH AND WRAPPED UP LOW PRESSURE SYSTEM WITH TOWARD 1 INCH OF QPF ACROSS UPPER LAKES. ECMWF NOT IN AGREEMENT AT ALL WHILE THE GEM-NH SHOWS SOME IDEA THERE COULD BE SOME PRECIP... JUST NOT AS STRONG AS GFS. CONSENSUS...WHICH IS WEIGHTED TOWARD GFS INPUT... GIVES ANOTHER ROUND OF CHANCE POPS FOR FRIDAY. MANUALLY TWEAKED THOSE DOWN SLIGHTLY...BUT LEFT ALONE OTHERWISE. CRITICAL THICKNESSES AND FORECASTED TEMPS INDICATE RAIN OR SNOW IS POSSIBLE. TEMPS FRIDAY AND INTO SATURDAY WILL BE HIGHLY DEPENDANT ON WHETHER ANY SYSTEM IS IN THE VCNTY. IF SO...TEMPS WILL PROBABLY STAY IN THE 30S WITH THE CLOUDS AND PRECIPITATION. IF NOT...INLAND AREAS AWAY FM THE LAKES COULD REACH LOWER 50S ONE OR BOTH OF THESE DAYS AS H85 TEMPS ARE WITHIN A FEW DEGREES OF 0C. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 737 AM EDT SUN APR 13 2014 WITH AN UPSLOPE E WIND WITHIN SHALLOW COOL AIRMASS NORTH OF A STATIONARY FRONT IN THE LOWER GREAT LAKES...EXPECT VLIFR/BLO LANDING MINS TO PERSIST AT CMX/SAW THROUGH MID MORNING. IWD MAY ALSO DROP BACK TO IFR AS NW UPSLOPE WINDS DEVELOP THIS MORNING. EXPECT GRADUAL IMPROVEMENT TO MVFR WITH SOME DAYTIME HEATING IN THE AFTERNOON. DEPENDING ON THE TRACK OF A SFC LOW THAT IS FCST TO MOVE FROM THE PLAINS INTO THE GREAT LAKES TONIGHT AND THE LOCATION OF THE NW EDGE OF THE ACCOMPANYING PCPN AREA...SOME SN/IFR/LIFR CONDITIONS MAY RETURN TO SAW THIS EVENING. BUT SINCE MOST OF THE MODELS FCST THE HEAVIER PCPN TO REMAIN TO THE SE...WILL HAVE MFR CONDITIONS THAT DROP TO IFR LATE TONIGHT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 429 AM EDT SUN APR 13 2014 NORTH TO NORTHWEST GALE FORCE GUSTS TO 35 KNOTS EXPECTED ON MONDAY IN WAKE OF LOW PRESSURE SYSTEM LIFTING ACROSS SOUTHERN QUEBEC. PRESSURE GRADIENT WEAKENS BY MONDAY NIGHT TO RESULT IN WINDS LESS THAN 25 KNOTS BY THAT TIME. WINDS CURRENTLY FORECAST TO STAY MAINLY BLO 20 KNOTS REST OF THE WEEK...BUT THIS DEPENDS ON WHETHER ONE OR TWO LOW PRESSURE SYSTEMS IMPACT THE UPPER GREAT LAKES. THE TWO TIME FRAMES OF INTEREST WOULD BE WEDNESDAY AND WEDNESDAY NIGHT AND AGAIN ON FRIDAY. IF EITHER OF THESE LOW PRESSURE SYSTEMS DO OCCUR...THEN WINDS MAY END UP STRONGER THAN CURRENT FORECAST SHOWS. && .HYDROLOGY... ISSUED AT 429 AM EDT SUN APR 13 2014 RIVER HYDROGRAPHS INDICATE THAT ICE JAMS AT RKLM4/FRDM4 AND EVEN AT MSQM4 OVER THE LAST FEW DAYS HAVE BROKEN AND RIVERS HAVE LEVELED OFF. AS OF THIS MORNING...NO IMPACTS HAVE BEEN REPORTED FROM THE ICE JAMS. SEEMS THAT WITH THE COOLER TEMPS SEEN ON SATURDAY AND THE COOLER TEMPS EXPECTED FOR MUCH OF THE UPCOMING WEEK /HIGHS 20S TO 30S WITH LOWS WELL BLO FREEZING THROUGH AT LEAST WEDNESDAY/...WE HAVE PROBABLY REACHED THE END OF THIS INITIAL PERIOD OF SNOWMELT/RUNOFF. GIVEN ADDITIONAL OPPORTUNITIES FOR PRECIPITATION THIS WEEK AND WITH 4-9 INCHES OF SNOW WATER EQUIVALENT STILL OVER PARTS OF WESTERN AND CENTRAL UPPER MICHIGAN...THERE WILL BE PLENTY OF WATER AVAILABLE FOR THE SECOND PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS. APPEARS THAT WARMER TEMPS WHICH COULD START UP THE NEXT PERIOD OF SNOWMELT/RUNOFF WILL RETURN BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
509 AM EDT SUN APR 13 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 508 AM EDT SUN APR 13 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH NEAR THE WEST COAST WITH A DOWNSTREAM TROUGH FROM CNTRL CANADA INTO THE SW CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE NRN GREAT LAKES. A SHRTWV INTO SW WI NORTH OF A FRONTAL BOUNDARY FROM SW IA INTO NRN IL AND SRN LOWER MI...AND IN AN AREA OF STRONG LOW LEVEL MOISUTR INFLOW...SUPPORTED AN AREA OF TSRA OVER SE WI INTO SRN LAKE MICHIGAN. ANOTHER SIGNIFICANT SHRTWV WAS LIFTING FROM ERN CO/NM TOWARD THE CNTRL PLAINS. OTHERWISE...ONLY SOME PATCHY DRIZZLE AND AREAS OF FOG PREVAILED OVER UPPER MI AS MID LEVEL DRYING ABOVE 850 MB HAS SPREAD OVER THE AREA. TODAY...EXCEPT FOR THE LINGERING FOG EARLY...ESPECIALLY OVER THE E TO NE UPSLOPE FLOW AREAS IN CNTRL UPPER MI...QUIET WEATHER IS EXPECTED AS THE MAIN PCPN AREA WILL REMAIN CLOSER TO THE SFC FRONT NEAR THE IL/W BORDER. NRLY WINDS AND CLOUDS WILL KEEP TEMPS NEAR THE LOWER END OF GUIDANCE...IN THE LOWER 40S NORTH TO THE UPPER 40S SOUTH. TONIGHT...AS THE CNTRL PLAINS SHRTWV MOVES TOWARD THE GREAT LAKES AND UPPER LEVEL DIV ASSOCIATED WITH THE RIGHT ENTRANCE OF THE 130-140KT JET OVER NRN ONTARIO INCREASES...PCPN WILL EXPAND FROM FROM NRN WI INTO THE SE HALF OF UPPER MI. THE MODELS SHOW SIGNFICANT DIFFERENCES WITH HOW FAR TO THE NW THE HEAVIER PCPN SPREADS. THE NAM WITH THE STRONGEST 700-600 MB FGEN FCSTS HIGHER QPF AMOUNTS TO AROUND 0.50 INCH INTO CNTRL UPPER MI. THE REGIONAL-GEM...ECMWF AND GFS KEEP THE HEAVIER PCPN FARTHER TO THE SOUTHEAST. EVEN THOUGH THE STRONGER MID LEVEL DYNAMICS MAY BE POSSIBLE...SUSPECT THAT THE MOISTURE INFLOW TO THE NW PORTION OF THE PCPN SHIELD WILL BE LIMITED BY CONVECTION AND HEAVY RAIN CLOSER TO THE 850 MB FRONT. NEVERTHELESS QPF AMOUNTS OF 0.20 TO 0.40 INCH EAST OF A LINE FROM IMT-P53 COULD SUPPORT WET SNOW ACCUMULATIONS OF A FEW INCHES S COLDER AIR FILTERS INTO THE AREA BRINGING A CHANGEOVER FROM RAIN TO SNOW BY LATE EVENING. AS TEMPS FALL AT OR BELOW 30F CNTRL...SOME SLIPPERY AREA MAY DEVELOP ON UNTREATED ROADS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 429 AM EDT SUN APR 13 2014 MOST OF THE IMPACTS FROM THE SYSTEM MOVING ACROSS THE UPPER GREAT LAKES OCCUR JUST PRECEEDING THE LONG TERM. KEPT HIGHER LIKELY POPS OVER EAST THROUGH 18Z ON MONDAY AS LAST PUSH OF DIVERGENCE ALOFT AND LINGERING DEEP MOISTURE MAY GENERATE UP TO 0.10 INCH OF LIQUID PRECIP IN THE FORM OF AROUND 1 INCH OF WET SNOW. AWAY FM THIS AREA OF SNOW...HAVE JUST SOME SMALL CHANCES DUE TO UPSLOPE AND SOME MOISTURE OFF THE GAPS IN WESTERN LK SUPERIOR. DEEP MOISTURE WILL BE WELL TO THE EAST AND OVERALL WILL BE SEEING LARGER SCALE SUBSIDENCE OVER MUCH OF CWA BY LATE MONDAY MORNING...SO PROBABLY LOOKING AT FLURRIES OR VERY LIGHT SNOW SHOWERS. UNSEASONABLY DEEP TROUGHING WILL SETTLE OVER THE UPPER GREAT LAKES THE FIRST PART OF THE WEEK. QUITE COOL...WITH H85 TEMPS DOWN TO -18C ON TUESDAY IN THE AXIS OF THE TROUGHING. EVEN WITH GAPS OF OPEN WATER OVER ESPECIALLY WEST HALF OF LK SUPERIOR...DO NOT EXPECT MUCH IN WAY OF LAKE EFFECT LATER MONDAY THROUGH TUESDAY AS AIR IS DRY IN THE LARGER SCALE. SOUNDINGS FM GFS INDICATE AN INVERTED-V LOOK...WITH DRY SUB-CLOUD LAYER UP TO THE THIN MOIST LAYER AROUND H85. BECOMES SLIGHTLY MORE MOIST ON MONDAY NIGHT WITH NIGHTTIME COOLING...BUT EVEN THIS AFFECT SHOULD BE MINIMAL AS LARGER SCALE LOW-LEVELS ARE DOMINATED BY ANTICYCLONIC FLOW. MOST NOTEABLE WILL BE THE COLD...WITH DAYTIME TEMPS ON MONDAY FALLING TO THE UPR TEENS OR LOWER 20S BY LATE AFTN NEAR LK SUPERIOR AND WITH DAYTIME HIGHS ON TUESDAY STRUGGLING TO REACH 32 DEGREES...EVEN OVER SCNTRL. NORMAL HIGHS ON TUESDAY ARE IN THE UPPER 40S NEAR LK SUPERIOR AND INTO THE LOWER 50S NEAR THE WISCONSIN BORDER. DESPITE INCREASING SUNSHINE BY AFTERNOON...READINGS ON TUESDAY WILL END UP 20-25 DEGREES BELOW NORMAL. COOL TEMPS FOR THE NIGHTS AS WELL. MAINLY TEENS EXPECTED BOTH MONDAY NIGHT AND TUESDAY NIGHT...BUT SINGLE DIGITS POSSIBLE AT ANY INTERIOR LOCATION ON MONDAY NIGHT THAT CLEARS OUT BRIEFLY AND ALSO OVER THE EASTERN INTERIOR TUESDAY NIGHT. LATER TUESDAY NIGHT BUT MORE SO INTO WEDNESDAY AND WEDNESDAY NIGHT...GFS STILL SHOWING WIDESPREAD MODERATE QPF WHICH WOULD BE IN THE FORM OF SNOW. GFS HAS SHOWN THIS OVER ITS LAST 5 RUNS BACK TO 00Z ON 12 APRIL. ECMWF RATHER INSISTENT INDICATING WIDESPREAD QPF WILL BE MORE FROM DAKOTAS ACROSS MINNESOTA AND ACROSS FAR WESTERN CWA TO LK SUPERIOR. GFS IDEA IS MORE OR LESS SUPPORTED BY LAST COUPLE GEM-NH RUNS AND 12Z/12 APRIL RUN OF UKMET. DIVING IN MORE IT APPEARS THAT ALTHOUGH THE GFS AND ECMWF IDEAS LOOK SIMILAR IN THE LARGER SCALE /LEAD SHORTWAVE INITIALIZING SFC LOW OVER NORTHERN PLAINS WHILE STRONGER/LARGER SHORTWAVE TROUGH DROPS ACROSS SOUTH CENTRAL CANADA/ THEY DIFFER IN HOW MUCH PHASING OCCURS BTWN THE TWO UPPER LEVEL FEATURES. GFS IS SLOWER TO PHASE THUS BRINGS SFC LOW FARTHER EAST INITIALLY WHILE THE ECMWF PHASES QUICKER AND LIFTS THE LOW MORE NORTHEAST OVER WESTERN UPR MICHIGAN. LEAD SHORTWAVE WILL EMERGE OUT OF STRONG SHORTWAVE TROUGH CURRENTLY SHOWING UP WELL ON WV LOOP OVER THE GULF OF ALASKA. A CONSENSUS OF PRIMARY MODELS INDICATES HIGH CHANCES OVER CWA...BEGINNING VERY LATE TUESDAY NIGHT OVER THE FAR WEST...SPREADING ACROSS ALL CWA ON WEDNESDAY...AND LINGERING INTO THURSDAY MORNING MAINLY EASTERN CWA. PTYPE MAINLY SNOW...THOUGH ENOUGH LOW-LEVEL WARMING OCCURS OVER SCNTRL BY WEDNESDAY NIGHT TO RESULT IN MIX OF RAIN/SNOW. MODERATE SNOW AMOUNTS POSSIBLE...ESPECIALLY NORTH AND WEST CWA PER BLEND OF LATEST GFS/ECMWF/GEM-NH. MIXING RATIOS 2.5-3 G/KG INDICATE MODERATE SNOW AMOUNTS AS WELL WEDNESDAY AND WEDNESDAY NIGHT. 00Z RUN OF ECMWF HAS TRENDED CLOSER TO GFS/GEM-NH IDEAS. WILL LEAVE MENTION OF THIS SYSTEM OUT OF HWOMQT NOW THOUGH SINCE AS THIS IS THE FIRST ECMWF RUN TO SHOW SIMILAR SOLUTION TO GFS WITH THIS SYSTEM. UNCERTAINTY ONLY INCREASES BY FRIDAY AS RECENT RUNS OF GFS BRING ANOTHER SHORTWAVE TROUGH AND WRAPPED UP LOW PRESSURE SYSTEM WITH TOWARD 1 INCH OF QPF ACROSS UPPER LAKES. ECMWF NOT IN AGREEMENT AT ALL WHILE THE GEM-NH SHOWS SOME IDEA THERE COULD BE SOME PRECIP... JUST NOT AS STRONG AS GFS. CONSENSUS...WHICH IS WEIGHTED TOWARD GFS INPUT... GIVES ANOTHER ROUND OF CHANCE POPS FOR FRIDAY. MANUALLY TWEAKED THOSE DOWN SLIGHTLY...BUT LEFT ALONE OTHERWISE. CRITICAL THICKNESSES AND FORECASTED TEMPS INDICATE RAIN OR SNOW IS POSSIBLE. TEMPS FRIDAY AND INTO SATURDAY WILL BE HIGHLY DEPENDANT ON WHETHER ANY SYSTEM IS IN THE VCNTY. IF SO...TEMPS WILL PROBABLY STAY IN THE 30S WITH THE CLOUDS AND PRECIPITATION. IF NOT...INLAND AREAS AWAY FM THE LAKES COULD REACH LOWER 50S ONE OR BOTH OF THESE DAYS AS H85 TEMPS ARE WITHIN A FEW DEGREES OF 0C. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 125 AM EDT SUN APR 13 2014 WITH AN UPSLOPE E WIND WITHIN SHALLOW COOL AIRMASS N OF STNRY FNT IN THE LOWER GREAT LKS...EXPECT VLIFR/BLO LANDING MINS TO PERSIST AT CMX THRU SUNRISE. CONDITIONS AT SAW AND IWD SHOULD DETERIORATE TO LIFR/IFR RESPECTIVLEY WITH THE SLOW ARRIVAL OF MORE LLVL MSTR IN THE PRESENCE OF DIURNAL COOLING UNDER MID LVL DRYING AND LGT UPSLOPE WIND COMPONENT AT SAW/WEAKENING DOWNSLOPE WIND AT IWD. EXPECT GRADUAL IMPROVEMENT TO MVFR WITH SOME DAYTIME HEATING ON SUN. DEPENDING ON THE TRACK OF A SFC LO THAT IS FCST TO MOVE FM THE PLAINS INTO THE GREAT LKS TNGT AND THE LOCATION OF THE NW EDGE OF THE ACCOMPANYING PCPN AREA...SOME SN/IFR CONDITIONS MAY RETURN TO SAW THIS EVNG. BUT SINCE MOST OF THE MODELS FCST THE HEAVIER PCPN TO REMAIN TO THE SE...WL FCST JUST MVFR CONDITIONS FOR NOW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 429 AM EDT SUN APR 13 2014 NORTH TO NORTHWEST GALE FORCE GUSTS TO 35 KNOTS EXPECTED ON MONDAY IN WAKE OF LOW PRESSURE SYSTEM LIFTING ACROSS SOUTHERN QUEBEC. PRESSURE GRADIENT WEAKENS BY MONDAY NIGHT TO RESULT IN WINDS LESS THAN 25 KNOTS BY THAT TIME. WINDS CURRENTLY FORECAST TO STAY MAINLY BLO 20 KNOTS REST OF THE WEEK...BUT THIS DEPENDS ON WHETHER ONE OR TWO LOW PRESSURE SYSTEMS IMPACT THE UPPER GREAT LAKES. THE TWO TIME FRAMES OF INTEREST WOULD BE WEDNESDAY AND WEDNESDAY NIGHT AND AGAIN ON FRIDAY. IF EITHER OF THESE LOW PRESSURE SYSTEMS DO OCCUR...THEN WINDS MAY END UP STRONGER THAN CURRENT FORECAST SHOWS. && .HYDROLOGY... ISSUED AT 429 AM EDT SUN APR 13 2014 RIVER HYDROGRAPHS INDICATE THAT ICE JAMS AT RKLM4/FRDM4 AND EVEN AT MSQM4 OVER THE LAST FEW DAYS HAVE BROKEN AND RIVERS HAVE LEVELED OFF. AS OF THIS MORNING...NO IMPACTS HAVE BEEN REPORTED FROM THE ICE JAMS. SEEMS THAT WITH THE COOLER TEMPS SEEN ON SATURDAY AND THE COOLER TEMPS EXPECTED FOR MUCH OF THE UPCOMING WEEK /HIGHS 20S TO 30S WITH LOWS WELL BLO FREEZING THROUGH AT LEAST WEDNESDAY/...WE HAVE PROBABLY REACHED THE END OF THIS INITIAL PERIOD OF SNOWMELT/RUNOFF. GIVEN ADDITIONAL OPPORTUNITIES FOR PRECIPITATION THIS WEEK AND WITH 4-9 INCHES OF SNOW WATER EQUIVALENT STILL OVER PARTS OF WESTERN AND CENTRAL UPPER MICHIGAN...THERE WILL BE PLENTY OF WATER AVAILABLE FOR THE SECOND PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS. APPEARS THAT WARMER TEMPS WHICH COULD START UP THE NEXT PERIOD OF SNOWMELT/RUNOFF WILL RETURN BY NEXT WEEKEND. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...KC MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
956 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 954 AM CDT SUN APR 13 2014 ADDED OCCASIONAL FLURRIES LATE THIS MORNING TO SECTIONS OF THE ARROWHEAD AND GOT RID OF MENTION OF EARLY MORNING FOG TO THE FORECAST. OTHERWISE...NO MAJOR CHANGES MADE TO THE FORECAST. && .SYNOPSIS... ISSUED AT 245 AM CDT SUN APR 13 2014 A SOMEWHAT BUSY SFC PRESS PATTERN EXISTS OVER THE CWA EARLY THIS MORNING. THE PRIMARY BAROCLINIC ZONE IS LOCATED SOUTH OF THE REGION AND ID ASSOCIATED WITH THE SRN PLAINS SFC LOW/ELONGATED TROUGH STRETCHING INTO SRN WISC/MICHIGAN. AS UPPER FLOW AMPLIFIES OVER CTRL CANADA..AN INVERTED SFC TROUGH HAS DEVELOPED AS ADVERTISED FROM SRN BDRY NORTH INTO A WEAK SFC WAVE OVER NWRN ONTARIO. A WELL DEFINED LOW LVL THETAE RIBBON ALONG WITH A DISTINCT WINDSHIFT IS ACCOMPANYING THIS FEATURE. GUSTY WINDS DEVELOP BEHIND THE BDRY AS SFC PGF IS INCREASING QUICKLY. SPOTTY PRECIP IS OCCURRING ALONG THE BORDERLAND AT THIS HOUR. IN BETWEEN THE TWO SYSTEMS A RELATIVE BENIGN LOW LVL WIND PATTERN... COMBINED WITH VERY LOW COND PRESS DEFICITS IN THE BDRY LYR... HAS ALLOWED LOCALLY DENSE FOG/AND LITE PRECIP TO LINGER NEAR THE TWIN PORTS AND ALONG THE NORTH SHORE OF LAKE SUPERIOR. && .SHORT TERM...(TODAY...TONIGHT...MONDAY) ISSUED AT 245 AM CDT SUN APR 13 2014 TODAY...EARLY MORNING FOG/DRIZZLE/CLOUDS WILL BEGIN TO DECREASE BY MID MORNING AS WINDSHIFT ASSOCIATED WITH SFC BDRY PUSHES INTO THE CWA. A DEEPENING OF THE COLD AIR ADVECTION WILL PRODUCE INCREASINGLY GUSTY WINDS AS MOMENTUM TRANSFER IS FAVORED WITHIN A PROGRESSIVELY MORE UNIDIRECTIONAL FLOW IN THE MIXING LAYER. MID LVL FLOW WILL CONTINUE TO BACK OVER NRN PLAINS AND THIS MAY ALLOW NRN FRINGE OF PRECIP FROM PLAINS SYSTEM TO EDGE INTO SERN CWA. MULTI MDL QPF SUPPORTS THIS IDEA. MAX TEMPS BLO CLIMO WITH CAA AND ABUNDANCE OF CLOUDY COVER. FCST 925/850 LAPSE RATES SUGGEST SOME ADDITIONAL INSTABILITY CU MAY BE FAVORED OVER NRN/ERN CWA IN THE AFTN HRS. TONIGHT...MID LVL TROF AMPLIFIES OVER WRN MN AS SFC HIGH PRESSURE BUILDS EAST OVER THE REGION. PRECIP WILL END AS SNOW OVER SERN CWA HOWEVER AT THIS TIME DO NOT ANTICIPATE ANY SIG ACCUMULATION. SREF PLUMES AT KPBH SHOW CONSIDERABLE SPREAD WITH MEAN NEAR AN INCH. TOMORROW...MAIN STORY TOMORROW WILL BE THE PROGRESSION OF THE MID LVL TROF OVER THE CWA WITH A CORRESPONDING INCREASE IN LOW LVL LAPSE RATES. MDLS ARE SKIMPY ON PRECIP HOWEVER GIVEN THE MAGNITUDE OF THE UPPER FEATURE AND THE TIME OF YEAR WOULD SUSPECT THAT INSTABILITY SNOW SHOWERS MAY DEVELOP. MAIN LIMITING FACTOR MAY BE LACK OF SUFFICIENT MOISTURE AND TREND TOWARDS INCREASING SUBSIDENCE INVERSION DURING THE DAY. WELL MIXED BDRY LAYER LOOKS LIKELY AS FCST MIXING LAYER HEIGHT REACHES 6K TO 7K FT DURING THE DAY. THIS SHOULD PROMOTE GUSTY WINDS ONCE AGAIN IN MANY AREAS. MAX TEMPS EVEN LOWER THAN SUNDAY DUE TO A DROP OF ABOUT 4C TO 6C WITHIN THE FCST 925/85H LAYER. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 245 AM CDT SUN APR 13 2014 THE PERIOD WILL BE UNSETTLED...WITH A CHANCE FOR SOME SIGNIFICANT SNOW MID WEEK. MOST OF THE WEEK WILL ALSO BE COLDER THAN NORMAL. A LONG WAVE UPPER TROUGH AXIS WILL SHIFT EAST OF THE NORTHLAND MONDAY NIGHT INTO TUESDAY WITH MOST AREAS DRY. THERE MAY BE SOME SNOW SHOWERS THAT LINGER OVER THE ARROWHEAD AND ALONG THE SOUTH SHORE MONDAY NIGHT...BUT ANY ACCUMULATION LOOKS TO BE LIGHT. EMPHASIS DURING THIS PERIOD WILL BE ON A CHANCE FOR SNOW LATE TUESDAY NIGHT INTO WEDNESDAY NIGHT. THERE CONTINUES TO BE SOME SIGNIFICANT DIFFERENCES WITH THIS SYSTEM...WITH THE GFS QUITE A BIT FASTER BRINGING IN THE SNOW TUESDAY NIGHT. THE ECMWF AND NAM ARE IN A BIG BETTER AGREEMENT ON A SLOWER PROGRESSION. THE MODELS ARE IN AGREEMENT IN DEVELOPING AN AREA OF LOW PRESSURE IN A BAROCLINIC ZONE THAT WILL RESIDE OVER THE REGION. AT THIS TIME...MUCH OF THE REGION LOOKS TO BE COLD ENOUGH TO RECEIVE SNOW. SEVERAL INCHES OF SNOW LOOK LIKELY WITH THIS SYSTEM...BUT THERE STILL IS QUITE A BIT OF UNCERTAINTY IN WHERE AND HOW MUCH WILL FALL AT ANY GIVEN LOCATION. THERE SHOULD BE SOME DECENT FGEN THAT IS ASSOCIATED WITH THIS SYSTEM AS WELL...AND COULD PROVIDE SOME ENHANCED BANDS OF SNOWFALL. BOTH THE GFS/ECMWF AGREE ON DIMINISHING THE CHANCE FOR SNOW QUITE A BIT WEDNESDAY NIGHT. HOWEVER...THE GFS DOES HAVE A MUCH STRONGER UPPER WAVE OVER THE DAKOTAS/MINNESOTA THURSDAY MORNING...THEN DEVELOPS IT INTO AN UPPER LOW OVER MINNESOTA FRIDAY. THE ECMWF IS MORE PROGRESSIVE AND DOES NOT HAVE NEARLY THE AMOUNT OF PRECIP FRIDAY/FRIDAY NIGHT THAT THE GFS SUGGESTS WILL OCCUR OVER THE EASTERN HALF OF THE NORTHLAND. WE HAVE LOW CONFIDENCE IN THE FORECAST DETAILS BEYOND WEDNESDAY. MOST OF THE PERIOD WILL FEATURE BELOW NORMAL TEMPERATURES...WITH THEM RISING LATE IN THE PERIOD TOWARD NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 701 AM CDT SUN APR 13 2014 IFR CEILINGS COVERED MUCH OF THE NORTHLAND....WITH 1SM TO 3SM IN FOG IN SPOTS. CEILINGS/VSBYS SHOULD RISE THIS MORNING AS LOW LEVEL WINDS INCREASE WITH THE TIGHTENING PRESSURE GRADIENT. WINDS WILL BECOME QUITE GUSTY AS WELL AS THE DAY PROGRESSES. THE RAP IS SLOWER TO LIFT CEILINGS TO VFR THAN WHAT THE NAM SOUNDINGS/LOW LEVEL RH SUGGEST. WE FOLLOWED CLOSER TO THE RAP. MOST AREAS SHOULD RISE TO VFR LATE THIS AFTERNOON INTO THE EVENING. && .PRELIMINARY POINT TEMPS/POPS... DLH 38 21 31 16 / 0 10 20 10 INL 35 15 27 9 / 10 10 20 10 BRD 39 22 34 16 / 0 0 10 10 HYR 41 23 34 11 / 10 10 20 10 ASX 41 24 32 15 / 10 10 20 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...BJT SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...MELDE AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
702 AM CDT SUN APR 13 2014 .SYNOPSIS... ISSUED AT 245 AM CDT SUN APR 13 2014 A SOMEWHAT BUSY SFC PRESS PATTERN EXISTS OVER THE CWA EARLY THIS MORNING. THE PRIMARY BAROCLINIC ZONE IS LOCATED SOUTH OF THE REGION AND ID ASSOCIATED WITH THE SRN PLAINS SFC LOW/ELONGATED TROUGH STRETCHING INTO SRN WISC/MICHIGAN. AS UPPER FLOW AMPLIFIES OVER CTRL CANADA..AN INVERTED SFC TROUGH HAS DEVELOPED AS ADVERTISED FROM SRN BDRY NORTH INTO A WEAK SFC WAVE OVER NWRN ONTARIO. A WELL DEFINED LOW LVL THETAE RIBBON ALONG WITH A DISTINCT WINDSHIFT IS ACCOMPANYING THIS FEATURE. GUSTY WINDS DEVELOP BEHIND THE BDRY AS SFC PGF IS INCREASING QUICKLY. SPOTTY PRECIP IS OCCURRING ALONG THE BORDERLAND AT THIS HOUR. IN BETWEEN THE TWO SYSTEMS A RELATIVE BENIGN LOW LVL WIND PATTERN... COMBINED WITH VERY LOW COND PRESS DEFICITS IN THE BDRY LYR... HAS ALLOWED LOCALLY DENSE FOG/AND LITE PRECIP TO LINGER NEAR THE TWIN PORTS AND ALONG THE NORTH SHORE OF LAKE SUPERIOR. && .SHORT TERM...(TODAY...TONIGHT...MONDAY) ISSUED AT 245 AM CDT SUN APR 13 2014 TODAY...EARLY MORNING FOG/DRIZZLE/CLOUDS WILL BEGIN TO DECREASE BY MID MORNING AS WINDSHIFT ASSOCIATED WITH SFC BDRY PUSHES INTO THE CWA. A DEEPENING OF THE COLD AIR ADVECTION WILL PRODUCE INCREASINGLY GUSTY WINDS AS MOMENTUM TRANSFER IS FAVORED WITHIN A PROGRESSIVELY MORE UNIDIRECTIONAL FLOW IN THE MIXING LAYER. MID LVL FLOW WILL CONTINUE TO BACK OVER NRN PLAINS AND THIS MAY ALLOW NRN FRINGE OF PRECIP FROM PLAINS SYSTEM TO EDGE INTO SERN CWA. MULTI MDL QPF SUPPORTS THIS IDEA. MAX TEMPS BLO CLIMO WITH CAA AND ABUNDANCE OF CLOUDY COVER. FCST 925/850 LAPSE RATES SUGGEST SOME ADDITIONAL INSTABILITY CU MAY BE FAVORED OVER NRN/ERN CWA IN THE AFTN HRS. TONIGHT...MID LVL TROF AMPLIFIES OVER WRN MN AS SFC HIGH PRESSURE BUILDS EAST OVER THE REGION. PRECIP WILL END AS SNOW OVER SERN CWA HOWEVER AT THIS TIME DO NOT ANTICIPATE ANY SIG ACCUMULATION. SREF PLUMES AT KPBH SHOW CONSIDERABLE SPREAD WITH MEAN NEAR AN INCH. TOMORROW...MAIN STORY TOMORROW WILL BE THE PROGRESSION OF THE MID LVL TROF OVER THE CWA WITH A CORRESPONDING INCREASE IN LOW LVL LAPSE RATES. MDLS ARE SKIMPY ON PRECIP HOWEVER GIVEN THE MAGNITUDE OF THE UPPER FEATURE AND THE TIME OF YEAR WOULD SUSPECT THAT INSTABILITY SNOW SHOWERS MAY DEVELOP. MAIN LIMITING FACTOR MAY BE LACK OF SUFFICIENT MOISTURE AND TREND TOWARDS INCREASING SUBSIDENCE INVERSION DURING THE DAY. WELL MIXED BDRY LAYER LOOKS LIKELY AS FCST MIXING LAYER HEIGHT REACHES 6K TO 7K FT DURING THE DAY. THIS SHOULD PROMOTE GUSTY WINDS ONCE AGAIN IN MANY AREAS. MAX TEMPS EVEN LOWER THAN SUNDAY DUE TO A DROP OF ABOUT 4C TO 6C WITHIN THE FCST 925/85H LAYER. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 245 AM CDT SUN APR 13 2014 THE PERIOD WILL BE UNSETTLED...WITH A CHANCE FOR SOME SIGNIFICANT SNOW MID WEEK. MOST OF THE WEEK WILL ALSO BE COLDER THAN NORMAL. A LONG WAVE UPPER TROUGH AXIS WILL SHIFT EAST OF THE NORTHLAND MONDAY NIGHT INTO TUESDAY WITH MOST AREAS DRY. THERE MAY BE SOME SNOW SHOWERS THAT LINGER OVER THE ARROWHEAD AND ALONG THE SOUTH SHORE MONDAY NIGHT...BUT ANY ACCUMULATION LOOKS TO BE LIGHT. EMPHASIS DURING THIS PERIOD WILL BE ON A CHANCE FOR SNOW LATE TUESDAY NIGHT INTO WEDNESDAY NIGHT. THERE CONTINUES TO BE SOME SIGNIFICANT DIFFERENCES WITH THIS SYSTEM...WITH THE GFS QUITE A BIT FASTER BRINGING IN THE SNOW TUESDAY NIGHT. THE ECMWF AND NAM ARE IN A BIG BETTER AGREEMENT ON A SLOWER PROGRESSION. THE MODELS ARE IN AGREEMENT IN DEVELOPING AN AREA OF LOW PRESSURE IN A BAROCLINIC ZONE THAT WILL RESIDE OVER THE REGION. AT THIS TIME...MUCH OF THE REGION LOOKS TO BE COLD ENOUGH TO RECEIVE SNOW. SEVERAL INCHES OF SNOW LOOK LIKELY WITH THIS SYSTEM...BUT THERE STILL IS QUITE A BIT OF UNCERTAINTY IN WHERE AND HOW MUCH WILL FALL AT ANY GIVEN LOCATION. THERE SHOULD BE SOME DECENT FGEN THAT IS ASSOCIATED WITH THIS SYSTEM AS WELL...AND COULD PROVIDE SOME ENHANCED BANDS OF SNOWFALL. BOTH THE GFS/ECMWF AGREE ON DIMINISHING THE CHANCE FOR SNOW QUITE A BIT WEDNESDAY NIGHT. HOWEVER...THE GFS DOES HAVE A MUCH STRONGER UPPER WAVE OVER THE DAKOTAS/MINNESOTA THURSDAY MORNING...THEN DEVELOPS IT INTO AN UPPER LOW OVER MINNESOTA FRIDAY. THE ECMWF IS MORE PROGRESSIVE AND DOES NOT HAVE NEARLY THE AMOUNT OF PRECIP FRIDAY/FRIDAY NIGHT THAT THE GFS SUGGESTS WILL OCCUR OVER THE EASTERN HALF OF THE NORTHLAND. WE HAVE LOW CONFIDENCE IN THE FORECAST DETAILS BEYOND WEDNESDAY. MOST OF THE PERIOD WILL FEATURE BELOW NORMAL TEMPERATURES...WITH THEM RISING LATE IN THE PERIOD TOWARD NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 701 AM CDT SUN APR 13 2014 IFR CEILINGS COVERED MUCH OF THE NORTHLAND....WITH 1SM TO 3SM IN FOG IN SPOTS. CEILINGS/VSBYS SHOULD RISE THIS MORNING AS LOW LEVEL WINDS INCREASE WITH THE TIGHTENING PRESSURE GRADIENT. WINDS WILL BECOME QUITE GUSTY AS WELL AS THE DAY PROGRESSES. THE RAP IS SLOWER TO LIFT CEILINGS TO VFR THAN WHAT THE NAM SOUNDINGS/LOW LEVEL RH SUGGEST. WE FOLLOWED CLOSER TO THE RAP. MOST AREAS SHOULD RISE TO VFR LATE THIS AFTERNOON INTO THE EVENING. && .PRELIMINARY POINT TEMPS/POPS... DLH 39 21 31 16 / 10 10 20 10 INL 35 15 27 9 / 10 10 20 10 BRD 41 22 34 16 / 10 10 0 10 HYR 43 23 34 11 / 10 10 20 10 ASX 42 24 32 15 / 10 10 20 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...MELDE AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
830 PM CDT Mon Apr 14 2014 .UPDATE: Issued at 830 PM CDT Mon Apr 14 2014 Band of snow has effectively left our CWA leaving behind a region of drizzle in its wake, now primarily confined to parts of southwest IL. The clearing line has made it almost to Jacksonville, IL, just passed thru Bowling Green, MO and near Rolla, MO. At its current rate, the skies are expected to clear for nearly the entire CWA by 06z, just in time for the start of a total lunar eclipse. Diurnal cloudiness driving southeast from IA is expected to further break up and dissipate over the next few hours. Temps continue to be on track with current forecast, supporting continuation of Freeze Warnings with widespread mins in the mid to upper 20s. Note that our forecast will either set or approach current record low temps. See CLIMATE section below. TES && .SHORT TERM: (Through Late Tonight) Issued at 324 PM CDT Mon Apr 14 2014 Main concerns deal with the band of snow currently extending from near Pittsfield to Rolla as well as the going freeze warning. The band has been reducing visibilities to as low as 1/2 mile with some reports of accumulation on grassy surfaces. It is being caused by mid level frontogenesis ahead of the 500mb trough that will move through the area tonight. The RAP and HRRR does show the frotogenesis weakening as it moves acrosss the CWA, but do think that it will likely maintain itself the next few hours before it weakens by early evening. Have extrapolated the band through CWA through early evening, with little or no accumulation of snow expected given the warm low level and surface temperatures. The precipitation and clouds will clear out quick as subsidence moves in behind the passage of the upper trough. With cold air advection and dry dewpoints, expect temperatures to drop quickly to near MOS temperatures. Going freeze warning looks good and plan no changes to it. Britt .LONG TERM: (Tuesday through Next Monday) Issued at 324 PM CDT Mon Apr 14 2014 (Tuesday through Thursday) Have kept Tuesday into Thursday dry as the area will remain cut off from any notable moisture from the Gulf and the active storm track stays north of the area. While Tuesday night will not be as cold as tonight, most areas will still be in the lower to mid 30s for lows. (Thursday Night-Next Monday) The ECMWF and GFS are now similar with the amplitude and timing of the mid level trough and attendant cold front that will move across the area on Friday. Will continue with the chance of showers on Thursday night and Friday before subsidence works in behind the trough keeping Friday night and Saturday dry. Then confidence begins to wane late in the weekend as they both develop QPF over the area. The GFS is placing more emphasis on an northern stream upper over the Upper Midwest while ECMWF is placing it`s emphasis on a shortwave coming out of the southwest CONUS. Either way, will continue the chance of showers we have going Saturday night into Sunday night. Temperatures during the period look to be near or slightly below normal. Britt && .AVIATION: (For the 00z TAFs through 00z Tuesday Evening) Issued at 654 PM CDT Mon Apr 14 2014 Back edge of light snow and mvfr cigs making progress to the east early this evening. Should see skies scatter out by 01z at KCOU and KUIN, and in the metro area by 02z. Otherwise, gusty northwest winds to diminish as surface ridge builds in then back to the west by midday on Tuesday. Specifics for KSTL: Back edge of light snow and mvfr cigs making progress to the east early this evening. Should see skies scatter out by 02z in the metro area. Otherwise, gusty northwest winds to diminish by 06z as surface ridge builds in then back to the west by 17z Tuesday then to the south by 01z Wednesday. Byrd && .CLIMATE: RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FREEZE WARNING until 9 AM CDT Tuesday FOR Audrain MO-Boone MO- Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO- Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...FREEZE WARNING until 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL- Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL- Pike IL-Randolph IL-St. Clair IL-Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
655 PM CDT Mon Apr 14 2014 .UPDATE: Issued at 607 PM CDT Mon Apr 14 2014 Band of pcpn of what is mostly snow is actually moving more to the northeast than east, and as a result, should only very briefly affect portions of STL Metro East early this evening, and many areas further E and S not at all, such as Salem and Sparta, IL. Have this band of pcpn exiting the CWA into central IL around 9pm, weakening as it does so. Isolated pockets of slush on grassy areas expected with most locations not getting any accums at all, with relatively warm surfaces from recent warm days and above freezing air temps currently. Still looking good for lunar eclipse viewing later tonight with clearing already making its way into central MO and this will sweep eastward across much of the CWA this evening. Freeze warnings still look on target with widespread mins in the mid-upper 20s. TES && .SHORT TERM: (Through Late Tonight) Issued at 324 PM CDT Mon Apr 14 2014 Main concerns deal with the band of snow currently extending from near Pittsfield to Rolla as well as the going freeze warning. The band has been reducing visibilities to as low as 1/2 mile with some reports of accumulation on grassy surfaces. It is being caused by mid level frontogenesis ahead of the 500mb trough that will move through the area tonight. The RAP and HRRR does show the frotogenesis weakening as it moves acrosss the CWA, but do think that it will likely maintain itself the next few hours before it weakens by early evening. Have extrapolated the band through CWA through early evening, with little or no accumulation of snow expected given the warm low level and surface temperatures. The precipitation and clouds will clear out quick as subsidence moves in behind the passage of the upper trough. With cold air advection and dry dewpoints, expect temperatures to drop quickly to near MOS temperatures. Going freeze warning looks good and plan no changes to it. Britt .LONG TERM: (Tuesday through Next Monday) Issued at 324 PM CDT Mon Apr 14 2014 (Tuesday through Thursday) Have kept Tuesday into Thursday dry as the area will remain cut off from any notable moisture from the Gulf and the active storm track stays north of the area. While Tuesday night will not be as cold as tonight, most areas will still be in the lower to mid 30s for lows. (Thursday Night-Next Monday) The ECMWF and GFS are now similar with the amplitude and timing of the mid level trough and attendant cold front that will move across the area on Friday. Will continue with the chance of showers on Thursday night and Friday before subsidence works in behind the trough keeping Friday night and Saturday dry. Then confidence begins to wane late in the weekend as they both develop QPF over the area. The GFS is placing more emphasis on an northern stream upper over the Upper Midwest while ECMWF is placing it`s emphasis on a shortwave coming out of the southwest CONUS. Either way, will continue the chance of showers we have going Saturday night into Sunday night. Temperatures during the period look to be near or slightly below normal. Britt && .AVIATION: (For the 00z TAFs through 00z Tuesday Evening) Issued at 654 PM CDT Mon Apr 14 2014 Back edge of light snow and mvfr cigs making progress to the east early this evening. Should see skies scatter out by 01z at KCOU and KUIN, and in the metro area by 02z. Otherwise, gusty northwest winds to diminish as surface ridge builds in then back to the west by midday on Tuesday. Specifics for KSTL: Back edge of light snow and mvfr cigs making progress to the east early this evening. Should see skies scatter out by 02z in the metro area. Otherwise, gusty northwest winds to diminish by 06z as surface ridge builds in then back to the west by 17z Tuesday then to the south by 01z Wednesday. Byrd && .CLIMATE: RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO- Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-Marion MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
607 PM CDT Mon Apr 14 2014 .UPDATE: Issued at 607 PM CDT Mon Apr 14 2014 Band of pcpn of what is mostly snow is actually moving more to the northeast than east, and as a result, should only very briefly affect portions of STL Metro East early this evening, and many areas further E and S not at all, such as Salem and Sparta, IL. Have this band of pcpn exiting the CWA into central IL around 9pm, weakening as it does so. Isolated pockets of slush on grassy areas expected with most locations not getting any accums at all, with relatively warm surfaces from recent warm days and above freezing air temps currently. Still looking good for lunar eclipse viewing later tonight with clearing already making its way into central MO and this will sweep eastward across much of the CWA this evening. Freeze warnings still look on target with widespread mins in the mid-upper 20s. TES && .SHORT TERM: (Through Late Tonight) Issued at 324 PM CDT Mon Apr 14 2014 Main concerns deal with the band of snow currently extending from near Pittsfield to Rolla as well as the going freeze warning. The band has been reducing visibilities to as low as 1/2 mile with some reports of accumulation on grassy surfaces. It is being caused by mid level frontogenesis ahead of the 500mb trough that will move through the area tonight. The RAP and HRRR does show the frotogenesis weakening as it moves acrosss the CWA, but do think that it will likely maintain itself the next few hours before it weakens by early evening. Have extrapolated the band through CWA through early evening, with little or no accumulation of snow expected given the warm low level and surface temperatures. The precipitation and clouds will clear out quick as subsidence moves in behind the passage of the upper trough. With cold air advection and dry dewpoints, expect temperatures to drop quickly to near MOS temperatures. Going freeze warning looks good and plan no changes to it. Britt .LONG TERM: (Tuesday through Next Monday) Issued at 324 PM CDT Mon Apr 14 2014 (Tuesday through Thursday) Have kept Tuesday into Thursday dry as the area will remain cut off from any notable moisture from the Gulf and the active storm track stays north of the area. While Tuesday night will not be as cold as tonight, most areas will still be in the lower to mid 30s for lows. (Thursday Night-Next Monday) The ECMWF and GFS are now similar with the amplitude and timing of the mid level trough and attendant cold front that will move across the area on Friday. Will continue with the chance of showers on Thursday night and Friday before subsidence works in behind the trough keeping Friday night and Saturday dry. Then confidence begins to wane late in the weekend as they both develop QPF over the area. The GFS is placing more emphasis on an northern stream upper over the Upper Midwest while ECMWF is placing it`s emphasis on a shortwave coming out of the southwest CONUS. Either way, will continue the chance of showers we have going Saturday night into Sunday night. Temperatures during the period look to be near or slightly below normal. Britt && .AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon) Issued at 1208 PM CDT Mon Apr 14 2014 Area of SN continues to move ewd. Have made some slight changes to the prev TAFs based on latest RADAR trends and mdl guidance. Confidence is higher that precip will be all SN at COU/UIN early this afternoon. With ample cloud cover across the region, believe temps will remain cold enuf for all SN at SUS/CPS late this afternoon. However, with some uncertainty and since main focus shud be nw of sites, will leave precip as a RA/SN mix for now. Beyond precip, cigs shud lift quickly and remain VFR thru the remainder of the TAF period. Specifics for KSTL: With clouds expected to remain in place, precip this afternoon has a better chance of being SN. However, with placement of precip wrt the terminal, precip may remain as a very light RA or more likely DZ. Beyond precip this afternoon, cigs shud lift quickly to VFR and remain VFR thru the remainder of the TAF period. Tilly && .CLIMATE: RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO- Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-Marion MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
542 PM CDT Sun Apr 13 2014 .SHORT TERM: (Through Late Tonight) Issued at 359 PM CDT Sun Apr 13 2014 (Tonight-Monday Night) Main question tonight will be severe weather chances. Large area of stratiform rain currently over the CWA may suppress these chances as latest SPC objective MUCAPE analysis is mostly below 500 j/kg except across northern Missouri and west central Illinois. The latest runs of the HRRR has been trending toward weaker storms these evening because weaker instability. However, if the rain can mover out of the area, there are very steep lapse rates over the Central Plains that could help quickly destabilize the atmosphere ahead of the line of the storms currently over eastern Kansas. Deep layer shear between 00-03Z will be between 35-50kts which will be sufficient for organized severe storms. Otherwise, forecast did not require too much changes as I still expect front to march southeast across the CWA tonight. Thunderstorm threat will end with the front and change to a plain cold rain. Have kept likely chances to for rain on Monday as the ECMWF/GFS/NAM all mid-level frontogenesis moving across the region during the day. Also added likely chances over the eastern counties on Monday evening as ascent from the mid level trough will not clear the CWA until overnight Monday night. Forecast soundings and critical thicknesses still point to snow mixing with the rain from northwest to southeast during the day on Monday. Do not have any accumulating snow at the moment as the low atmosphere will be rather warm during the day, as will the surface temperatures after this unseasonably warm weekend. With the much colder air moving into the area, temperatures will fall below freezing over the entire CWA on Monday night. Many areas will see temperatures in the mid to upper 20s. Britt .LONG TERM: (Monday through Next Sunday) Issued at 359 PM CDT Sun Apr 13 2014 (Tuesday-Sunday) Upper trough will move east of the area by Tuesday bringing dry weather for mid week. While Monday night looks like the coldest, Tuesday night will likely still have temperatures around freezing before lows become more seasonable later in the week. While the ECMWF has trended deeper and consequently slower with the trough that will move through the central CONUS late this week, it is still not as deep as the GFS or the Canadian GEM. Will stick with the more consistent ECMWF as the GFS is quicker to move the front through the area on Thursday night than it was before. Will keep Thursday dry with the front staying to the northwest most of the day with a chance of showers Thursday night and Friday as the front moves across the area. By next weekend, winds turn out of the southwest quickly behind a retreating high allowing gulf moisture to move north from the Gulf quickly into the area. Britt && .AVIATION: (For the 00z TAFs through 00z Monday Evening) Issued at 512 PM CDT Sun Apr 13 2014 Cold front extending from a weak surface low over southeast IA southwest through northwest MO and southeast KS will move sewd through UIN and COU this evening, and through the St Louis metro area just after 06z Monday. Scattered showers will continue ahead of the front early this evening with a line of thunderstorms along the cold front moving through the taf sites later this evening. Relatively strong and gusty sly surface winds will veer around to a nwly direction after fropa and remain strong and gusty late tonight and Monday due to a tight surface pressure gradient. Ceilings will likely fall into the IFR catagory behind this front. There will be some post frontal light rain on Monday, possibly mixing with or changing to light snow in UIN and COU as colder air continues to filter sewd into the area. Specifics for KSTL: Showers and thunderstorms over south central MO will move northeastward into STL later this evening, while a line of thunderstorms along the cold front over northwest and west central MO moves into the STL area by late evening. Strong and gusty sly winds will veer around to a wly direction late tonight after fropa and a nwly direction Monday morning. The wind will remain strong and gusty through Monday, then diminish Monday night as a surface ridge approaches and the surface pressure gradient relaxes. The cloud ceiling will lower into the IFR catagory late tonight after fropa, then rise into the MVFR catagory Monday afternoon or evening. Periods of light rain can be expected on Monday, possibly changing to a little light rain/snow mix before ending Monday evening. GKS && .CLIMATE: Issued at 330 AM CDT Sun Apr 13 2014 RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
404 PM CDT Sun Apr 13 2014 .SHORT TERM: (Through Late Tonight) Issued at 359 PM CDT Sun Apr 13 2014 (Tonight-Monday Night) Main question tonight will be severe weather chances. Large area of stratiform rain currently over the CWA may suppress these chances as latest SPC objective MUCAPE analysis is mostly below 500 j/kg except across northern Missouri and west central Illinois. The latest runs of the HRRR has been trending toward weaker storms these evening because weaker instability. However, if the rain can mover out of the area, there are very steep lapse rates over the Central Plains that could help quickly destabilize the atmosphere ahead of the line of the storms currently over eastern Kansas. Deep layer shear between 00-03Z will be between 35-50kts which will be sufficient for organized severe storms. Otherwise, forecast did not require too much changes as I still expect front to march southeast across the CWA tonight. Thunderstorm threat will end with the front and change to a plain cold rain. Have kept likely chances to for rain on Monday as the ECMWF/GFS/NAM all mid-level frontogenesis moving across the region during the day. Also added likely chances over the eastern counties on Monday evening as ascent from the mid level trough will not clear the CWA until overnight Monday night. Forecast soundings and critical thicknesses still point to snow mixing with the rain from northwest to southeast during the day on Monday. Do not have any accumulating snow at the moment as the low atmosphere will be rather warm during the day, as will the surface temperatures after this unseasonably warm weekend. With the much colder air moving into the area, temperatures will fall below freezing over the entire CWA on Monday night. Many areas will see temperatures in the mid to upper 20s. Britt .LONG TERM: (Monday through Next Sunday) Issued at 359 PM CDT Sun Apr 13 2014 (Tuesday-Sunday) Upper trough will move east of the area by Tuesday bringing dry weather for mid week. While Monday night looks like the coldest, Tuesday night will likely still have temperatures around freezing before lows become more seasonable later in the week. While the ECMWF has trended deeper and consequently slower with the trough that will move through the central CONUS late this week, it is still not as deep as the GFS or the Canadian GEM. Will stick with the more consistent ECMWF as the GFS is quicker to move the front through the area on Thursday night than it was before. Will keep Thursday dry with the front staying to the northwest most of the day with a chance of showers Thursday night and Friday as the front moves across the area. By next weekend, winds turn out of the southwest quickly behind a retreating high allowing gulf moisture to move north from the Gulf quickly into the area. Britt && .AVIATION: (For the 18z TAFs through 18z Monday Afternoon) Issued at 1257 PM CDT Sun Apr 13 2014 Latest weather trends shows band of rainshowers from IRK through central Missouri and southwest into south central Missouri moving northeast into eastern sections of the state. Narrow band of thunderstorms entering west-central Missouri at this time shows recent signs of slight weakening. More organized storms continue to develop from TOP to ICT. Eastern Missouri and southwest Illinois will continue to receive light rainshowers this afternoon ending by 2100 - 2200 UTC. The stronger storms along far western Missouri shows trend of continued weakening as it hit more stable air over central Missouri. Will bring in rainshowers over COU...UIN...and STL terminal from 1800 UTC and ending precipitation between 2100 to 2200 UTC. The band of storms entering far western Missouri may reach COU area around 2300 - 0000 UTC if it holds together. Specifics for KSTL: Band of rainshowers from north central Missouri through south central Missouri will enter STL area after 1800 and should end around 2100 UTC. Expect visibility restrictions of about 5 miles in light rain. The stronger convection over far western Missouri may not reach STL since this system will be entering in more stable atmosphere. Stronger storms over east central through south-central Kansas is associated with the cold front. This band of storms will be entering the STL area after 0400 UTC. Gusty winds are likely with these storms. Surface winds will likely be southwest at 15 kts with gusts to as high as 25 kts. Przybylinski && .CLIMATE: Issued at 330 AM CDT Sun Apr 13 2014 RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
251 PM CDT Sun Apr 13 2014 .UPDATE... Issued at 1025 AM CDT SUN APR 13 2014 Forecast evolving much as expected this morning. 12z NAM is suggesting arrival into the SGF CWA to be 1-3 hours slower...with development of strong to severe storms east of I35 over eastern Kansas and Oklahoma toward 21z...reaching southeast Kansas and western Missouri in the 23-01z time frame. Convection currently most prevalent over northeast Oklahoma into western Missouri ahead of approaching lead 700 MB shortwave depicted over central Oklahoma at 12z but weakening as it moves into eastern Oklahoma per water vapor at 14z. Obviously enough jet support to lead to elevated convection though suspect this activity to further weaken by late morning as low level jet diminishes. AC deck in behind 700 MB shortwave westward into western OK has filled in a bit which may have a bearing on afternoon instability...though RUC and 12z NAM lower RH satisfactory to lead to 2000+ MLCAPE ahead of main 500 MB wave. Lastly...wavy surface front extending from near STJ to SLN to TX Panhandle with slug of low to mid 60 dew points surging northward through central OK. Dew points though east of I-35 drop considerable into the lower 50s over eastern OK. Lower dew points wont help CAP evident ab 12z SGF RAOB...though MDCRS aircraft soundings showing CAP weakening ahead of main shortwave. && .SHORT TERM...(This Evening through Monday Night) Issued at 1245 PM CDT SUN APR 13 2014 A strong cold front will sweep through the region tonight with unseasonable cold Mon/Mon night. Guidance is continuing to indicate light precip ahead of the main long wave trough axis over the Plains Monday. Progged vertical thermal profiles support some wet snow at many locations from mid morning into the afternoon, particularly over western and and northern halves of cwfa. Blustery, cold, and damp sums it up for the day on Monday. A widespread frost/hard freeze looks likely Mon night with most guidance dropping temperatures well down into the 20s. A sfc ridge axis will be over the region by 12z Tue with light winds aiding in radiational cooling. Freeze watch is out now for Mon night, and the warning will follow either later today or tonight. .LONG TERM...(Tuesday through Sunday) Issued at 1245 PM CDT SUN APR 13 2014 Cold temperatures and a dry air mass will continue into Tuesday. The sfc ridge axis will shift east of the area late Tue/Tue night. While a light south to southeast wind will become established over the area Tue night, the dry air mass will still likely allow temperatures to drop quickly in the evening and reach down to near freezing in many areas. Will look at at the possibility of a frost advisory as that time period draws closer. Temperatures will moderate somewhat for Wed-Thu. Another shortwave and sfc low/trough will pass through the region Thu night/early Fri. Gulf moisture will be greatly limited/modified ahead of this system with showers/isolate tstms expected. Looks like a more amplified upper level pattern may become established over the CONUS by late in the week with a sharp upper level ridge axis setting up over the eastern Rockies or Plains by late in the week. The 00z ECMWF is more progressive with the ridge (versus the 12z GFS), shifting it east of the area by Sunday and spitting out some light precip late in the weekend. Will probably hold off on any significant mention of precip for now with dry low levels expected to be in place with sfc high pressure just off to the east. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 640 AM CDT SUN APR 13 2014 Issued at 1225 PM CDT SUN APR 13 2014 We will continue to see scattered showers and storms over the southwest Missouri airports through the afternoon...however we expect ceilings to remain VFR ahead of the dry line and cold front which extended across south central Kansas through central Oklahoma at 17Z. A tight pressure gradient ahead of the front should keep winds gusting above 20 mph through the afternoon. Strong to severe thunderstorms could affect the airports roughly from 23Z to 3Z...as the cold front moves across the area. These storms could produce wind gusts in excess of 50 knots and hail to 1.75 inches in diameter. Winds will shift to the west and southwest around midnight with ceilings expected to drop to IFR through the night and into tomorrow. We could see the ceilings break before 18Z Monday with the passage of the 700 mb trough. Expect Springfield and Branson to remain IFR with periods of light rain through 18Z. && .CLIMATE... Issued at 247 PM CDT SUN APR 13 2014 Record lows for April 15th: Springfield: 25 deg F...1928 Joplin : 26 deg F...1983 West Plains: 25 deg F...1950 Rolla-Vichy: 27 deg F...1962 && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FREEZE WATCH from Monday evening through Tuesday morning FOR MOZ055>058-066>071-077>083-088>098-101>106. KS...FREEZE WATCH from Monday evening through Tuesday morning FOR KSZ073-097-101. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Foster CLIMATE...DSA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
149 PM CDT Sun Apr 13 2014 .MESOSCALE DISCUSSION... Issued at 119 PM CDT SUN APR 13 2014 Surface analysis at 18z indicated that a sharp and swiftly moving cold front is currently situated from Lamoni, IA to Manhattan, KS. Regional mosaic radar confirms this by indicating the fine line associated with the cold front. By 19z it appears FROPA will occur in the northern KC Metro, with FROPA for the entire metro area by 20z. Areas north of the cold front will no longer have any threat for tornadic activity. Areas along and south of the cold front will continue to have a threat for strong surface based storms, with a very low-end tornado threat for the rest of the afternoon. Cloud cover over the area has generally abated the instability, however visible imagery indicates plenty of clearing across SE Kansas, resulting in building instability along the order of 2000 to 3000 J/kg of SB Cape. Thunderstorm activity is ongoing deep within the warm sector, and likely will tap into the 2000+ J/kg of surface based instability and 20 to 40 kts of effective shear. It appears that these storms, numerous in nature, could potentially be tied to a potent shortwave trough which is currently centered over western Kansas with the leading edge moving over the warm sector in C/E Kansas. While the atmosphere certainly contains the ingredients for high-impact severe weather, it appears that the chances for widespread high-impact severe weather is minimal at this point, considering how storms appear to be evolving across C/E Kansas. HRRR trends over the past few runs confirm the idea that by 20z the storm activity will likely be widespread in coverage, which would likely hamper the ability for any single thunderstorm to become organized. Generally expect widespread strong thunderstorms to skirt through the northern KC Metro within the next couple of hours, with perhaps another round of storms moving into the KC Metro area closer to 21z to 23z. With that said, even with a linear or disorganized complex of storms, the aforementioned area of high instability will migrate eastward into the area, and wind profiles will be favorable for rotating storms, so it will be necessary to keep a close eye on any strong updraft within the complex for rotation. Behind the cold front some lingering instability will support post frontal thunderstorm activity, and with shear increasing behind the line it will be possible to see some quasi organized activity in the cold air behind the front, however it would almost surely be elevated in nature, making the only threat marginal to low-end severe hail. && .DISCUSSION... Issued at 344 AM CDT SUN APR 13 2014 Today: --------------------- Scattered, elevated thunderstorms may continue through the next several hours on the nose of the LLJ, and could continue to produce isolated severe hail in an environment with around 800-1000 J/kg of MUCAPE and 30-40 kts 0-6 km bulk shear. A brief lull in thunderstorm activity is possible around sunrise as ongoing storms push east; however, additional storm development is expected to begin along the nearly stationary surface front/inverted trough axis by mid morning across far NE Kansas and NW Missouri. Storms will gradually spread along the boundary this morning, then will push southeastward during the afternoon as the associated surface low kicks eastward into central MO and drags the front across the forecast area. Additional storm development is also possible early this afternoon just ahead of the surface low across east central KS and west central MO, but will gradually conglomerate with frontal precipitation during the mid-afternoon. MUCAPE values of 1000-1500 J/kg are possible along and ahead of the boundary this afternoon despite generally weak surface heating, and will be accompanied by deep-layer shear values of 30-40 kts. Low- level shear profiles are unidirectional and fairly unimpressive near the surface, keeping the tornado potential very low. If storms can become a bit more isolated just ahead of the surface boundary, large hail will be possible; but with fairly widespread convection and competing updrafts, shear vectors oriented nearly perpendicular to the boundary and overall uni-directional shear, briefly damaging winds and marginally severe (~1") hail seem the most likely candidate for a severe threat this afternoon-evening. Tonight and Monday: --------------------- Behind the surface front, much cooler temperatures will filter into the region. Profiles will quickly become supportive of a rain/snow mix or brief periods of all snow late tonight into early Monday morning, and fairly widespread (light) precipitation looks probable along the northwest side of the surface low. Accumulating snow will be very difficult to come by due to low snow rates and and very warm and wet surfaces, but can`t rule out a brief tenth of an inch or so on grassy surface across far northwest Missouri. Precipitation should taper off from northwest to southeast on Monday afternoon, exiting the region completely by sunset. Tuesday Morning: --------------------- A surface ridge will drift eastward across the forecast area late Monday night into Tuesday morning while chilly northwest flow aloft continues to usher in unseasonably cold temperatures. A damaging freeze is likely Tuesday morning for any vegetation that has bloomed out across the region, and a freeze headline will likely be needed as Tuesday AM draws closer. Wednesday - Saturday: --------------------- Gradually warming temperatures are expected through Thursday, then a clipper system may shove a cold front through the area again on Thursday night into Friday. The GFS is the most aggressive in bringing cold temperatures (and measurable snow) back into the CWA for Thursday night into Friday morning, but have kept a warmer blend in the forecast for now. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1247 PM CDT SUN APR 13 2014 Very messy afternoon with scattered convection early this afternoon from extreme eastern KS across northern and central MO before a line of strong/isolated severe storms moves from west to east this afternoon. This line should affect the terminals before 22z with MVFR cigs. Winds will switch abruptly to the north and remain strong and gusty with the passage of the front. Post-frontal rain and embedded thunderstorms will linger for a couple of hours after frontal passage. An area of wrap around rain and drizzle likely to move in later this evening. Temperatures should be cold enough for a rain/snow mix after midnight over far northwest MO. Another system moves in from the west on Monday with the entire column cooling well below zero such that snow is expected over east central KS/west central MO. Could see minor accumulations on grassy surfaces. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ MESOSCALE...Leighton DISCUSSION...Laflin AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
113 PM CDT Sun Apr 13 2014 .UPDATE... Issued at 1025 AM CDT SUN APR 13 2014 Forecast evolving much as expected this morning. 12z NAM is suggesting arrival into the SGF CWA to be 1-3 hours slower...with development of strong to severe storms east of I35 over eastern Kansas and Oklahoma toward 21z...reaching southeast Kansas and western Missouri in the 23-01z time frame. Convection currently most prevalent over northeast Oklahoma into western Missouri ahead of approaching lead 700 MB shortwave depicted over central Oklahoma at 12z but weakening as it moves into eastern Oklahoma per water vapor at 14z. Obviously enough jet support to lead to elevated convection though suspect this activity to further weaken by late morning as low level jet diminishes. AC deck in behind 700 MB shortwave westward into western OK has filled in a bit which may have a bearing on afternoon instability...though RUC and 12z NAM lower RH satisfactory to lead to 2000+ MLCAPE ahead of main 500 MB wave. Lastly...wavy surface front extending from near STJ to SLN to TX Panhandle with slug of low to mid 60 dew points surging northward through central OK. Dew points though east of I-35 drop considerable into the lower 50s over eastern OK. Lower dew points wont help CAP evident ab 12z SGF RAOB...though MDCRS aircraft soundings showing CAP weakening ahead of main shortwave. && .SHORT TERM...(This Evening through Monday Night) Issued at 1245 PM CDT SUN APR 13 2014 A strong cold front will sweep through the region tonight with unseasonable cold Mon/Mon night. Guidance is continuing to indicate light precip ahead of the main long wave trough axis over the Plains Monday. Progged vertical thermal profiles support some wet snow at many locations from mid morning into the afternoon, particularly over western and and northern halves of cwfa. Blustery, cold, and damp sums it up for the day on Monday. A widespread frost/hard freeze looks likely Mon night with most guidance dropping temperatures well down into the 20s. A sfc ridge axis will be over the region by 12z Tue with light winds aiding in radiational cooling. Freeze watch is out now for Mon night, and the warning will follow either later today or tonight. .LONG TERM...(Tuesday through Sunday) Issued at 1245 PM CDT SUN APR 13 2014 Cold temperatures and a dry air mass will continue into Tuesday. The sfc ridge axis will shift east of the area late Tue/Tue night. While a light south to southeast wind will become established over the area Tue night, the dry air mass will still likely allow temperatures to drop quickly in the evening and reach down to near freezing in many areas. Will look at at the possibility of a frost advisory as that time period draws closer. Temperatures will moderate somewhat for Wed-Thu. Another shortwave and sfc low/trough will pass through the region Thu night/early Fri. Gulf moisture will be greatly limited/modified ahead of this system with showers/isolate tstms expected. Looks like a more amplified upper level pattern may become established over the CONUS by late in the week with a sharp upper level ridge axis setting up over the eastern Rockies or Plains by late in the week. The 00z ECMWF is more progressive with the ridge (versus the 12z GFS), shifting it east of the area by Sunday and spitting out some light precip late in the weekend. Will probably hold off on any significant mention of precip for now with dry low levels expected to be in place with sfc high pressure just off to the east. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 640 AM CDT SUN APR 13 2014 Issued at 1225 PM CDT SUN APR 13 2014 We will continue to see scattered showers and storms over the southwest Missouri airports through the afternoon...however we expect ceilings to remain VFR ahead of the dry line and cold front which extended across south central Kansas through central Oklahoma at 17Z. A tight pressure gradient ahead of the front should keep winds gusting above 20 mph through the afternoon. Strong to severe thunderstorms could affect the airports roughly from 23Z to 3Z...as the cold front moves across the area. These storms could produce wind gusts in excess of 50 knots and hail to 1.75 inches in diameter. Winds will shift to the west and southwest around midnight with ceilings expected to drop to IFR through the night and into tomorrow. We could see the ceilings break before 18Z Monday with the passage of the 700 mb trough. Expect Springfield and Branson to remain IFR with periods of light rain through 18Z. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FREEZE WATCH from Monday evening through Tuesday morning FOR MOZ055>058-066>071-077>083-088>098-101>106. KS...FREEZE WATCH from Monday evening through Tuesday morning FOR KSZ073-097-101. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Foster
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1238 PM CDT Sun Apr 13 2014 .UPDATE... Issued at 1025 AM CDT SUN APR 13 2014 Forecast evolving much as expected this morning. 12z NAM is suggesting arrival into the SGF CWA to be 1-3 hours slower...with development of strong to severe storms east of I35 over eastern Kansas and Oklahoma toward 21z...reaching southeast Kansas and western Missouri in the 23-01z time frame. Convection currently most prevalent over northeast Oklahoma into western Missouri ahead of approaching lead 700 MB shortwave depicted over central Oklahoma at 12z but weakening as it moves into eastern Oklahoma per water vapor at 14z. Obviously enough jet support to lead to elevated convection though suspect this activity to further weaken by late morning as low level jet diminishes. AC deck in behind 700 MB shortwave westward into western OK has filled in a bit which may have a bearing on afternoon instability...though RUC and 12z NAM lower RH satisfactory to lead to 2000+ MLCAPE ahead of main 500 MB wave. Lastly...wavy surface front extending from near STJ to SLN to TX Panhandle with slug of low to mid 60 dew points surging northward through central OK. Dew points though east of I-35 drop considerable into the lower 50s over eastern OK. Lower dew points wont help CAP evident ab 12z SGF RAOB...though MDCRS aircraft soundings showing CAP weakening ahead of main shortwave. && .SHORT TERM...(Today through Monday) Issued at 252 AM CDT SUN APR 13 2014 It is a very mild and breezy morning across southeast Kansas and the Missouri Ozarks. Temperatures this morning are where our normal highs would be for this time of year. Some convection is already developing across portions of southeast Kansas this morning. This will continue to further develop and move northward. The 00z 4KM WFR model shows this development well and think that the model has a good handle of the evolution of storms today and this evening for the area. All the 00z suite of models show convection developing by 18z across southwestern Missouri into central Missouri in the warm sector. Bulk shear will be up to 50 knots. Instability will between 1000-1200 J/KG. 0-3KM Storm Relative Helicities will be up to 500 M2/S2. This convection may be strong to severe with the primary threats large hail and damaging wind gusts. There will be a low potential for an isolated tornado or two mainly late this afternoon into the early evening hours with the better potential over southeast Kansas into extreme southwestern Missouri. A strong to severe line of storms will be developing along the advancing cold front by 00z across southeast Kansas into western Missouri. The main threat again will be large hail and damaging wind gusts. The front will slowly undercut the line of storms through the evening hours as it advances southeastward. The front will be through Springfield before Midnight and through the eastern Ozarks before 6 am. Storm total rainfall will be around 1 inch with isolated amounts up to 2 inches. .LONG TERM...(Monday through Saturday) Issued at 252 AM CDT SUN APR 13 2014 Much colder air will be moving in on gusty northerly winds by Monday morning. The main trough will be moving through the area by the midday and early afternoon hours. Monday will be a shock compared to the nice warm weather this weekend. Cloudy and dreary conditions with north winds gusting up to 35 mph...off and on rain showers with temperatures falling most of the day into the middle and upper 30s...Wind chills will be in the 20s. There is still indications from the models and forecast soundings that enough cold air aloft will be available for either some wet snow mixing in or changing over by late morning to midday on Monday. The better potential for seeing wet snow falling will be along and north of the I-44 corridor and the higher elevations of the Ozark Plateau. No accumulations are expected with the warm ground temperatures and the air temperatures will be in the middle to upper 30s. Skies will clear from west to east Monday evening and temperatures will continue to drop as the Canadian high pressure moves in. There is high confidence that most of the area will see temperatures in the middle to upper 20s Monday night into Tuesday morning. Some patchy to areas of frost may occur if the wind relax enough and in sheltered areas. Will go ahead and issue a Freeze Watch area wide for Monday night. Temperatures will slowly moderate through the middle of the week. May see another round of frost and near freezing temperatures Tuesday night into Wednesday morning. Temperatures will be near seasonable averages by Thursday before another trough and cold front moves through and briefly cools temperatures back down for the end of the week. A good chance of showers will accompanying the cold front late Thursday into Friday. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1225 PM CDT SUN APR 13 2014 We will continue to see scattered showers and storms over the southwest Missouri airports through the afternoon...however we expect ceilings to remain VFR ahead of the dry line and cold front which extended across south central Kansas through central Oklahoma at 17Z. A tight pressure gradient ahead of the front should keep winds gusting above 20 mph through the afternoon. Strong to severe thunderstorms could affect the airports roughly from 23Z to 3Z...as the cold front moves across the area. These storms could produce wind gusts in excess of 50 knots and hail to 1.75 inches in diameter. Winds will shift to the west and southwest around midnight with ceilings expected to drop to IFR through the night and into tomorrow. We could see the ceilings break before 18Z Monday with the passage of the 700 mb trough. Expect Springfield and Branson to remain IFR with periods of light rain through 18Z. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FREEZE WATCH from Monday evening through Tuesday morning FOR MOZ055>058-066>071-077>083-088>098-101>106. KS...FREEZE WATCH from Monday evening through Tuesday morning FOR KSZ073-097-101. && $$ UPDATE...Runnels SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Terry
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1027 AM CDT Sun Apr 13 2014 .UPDATE... Issued at 1025 AM CDT SUN APR 13 2014 Forecast evolving much as expected this morning. 12z NAM is suggesting arrival into the SGF CWA to be 1-3 hours slower...with development of strong to severe storms east of I35 over eastern Kansas and Oklahoma toward 21z...reaching southeast Kansas and western Missouri in the 23-01z time frame. Convection currently most prevalent over northeast Oklahoma into western Missouri ahead of approaching lead 700 MB shortwave depicted over central Oklahoma at 12z but weakening as it moves into eastern Oklahoma per water vapor at 14z. Obviously enough jet support to lead to elevated convection though suspect this activity to further weaken by late morning as low level jet diminishes. AC deck in behind 700 MB shortwave westward into western OK has filled in a bit which may have a bearing on afternoon instability...though RUC and 12z NAM lower RH satisfactory to lead to 2000+ MLCAPE ahead of main 500 MB wave. Lastly...wavy surface front extending from near STJ to SLN to TX Panhandle with slug of low to mid 60 dew points surging northward through central OK. Dew points though east of I-35 drop considerable into the lower 50s over eastern OK. Lower dew points wont help CAP evident ab 12z SGF RAOB...though MDCRS aircraft soundings showing CAP weakening ahead of main shortwave. && .SHORT TERM...(Today through Monday) Issued at 252 AM CDT SUN APR 13 2014 It is a very mild and breezy morning across southeast Kansas and the Missouri Ozarks. Temperatures this morning are where our normal highs would be for this time of year. Some convection is already developing across portions of southeast Kansas this morning. This will continue to further develop and move northward. The 00z 4KM WFR model shows this development well and think that the model has a good handle of the evolution of storms today and this evening for the area. All the 00z suite of models show convection developing by 18z across southwestern Missouri into central Missouri in the warm sector. Bulk shear will be up to 50 knots. Instability will between 1000-1200 J/KG. 0-3KM Storm Relative Helicities will be up to 500 M2/S2. This convection may be strong to severe with the primary threats large hail and damaging wind gusts. There will be a low potential for an isolated tornado or two mainly late this afternoon into the early evening hours with the better potential over southeast Kansas into extreme southwestern Missouri. A strong to severe line of storms will be developing along the advancing cold front by 00z across southeast Kansas into western Missouri. The main threat again will be large hail and damaging wind gusts. The front will slowly undercut the line of storms through the evening hours as it advances southeastward. The front will be through Springfield before Midnight and through the eastern Ozarks before 6 am. Storm total rainfall will be around 1 inch with isolated amounts up to 2 inches. .LONG TERM...(Monday through Saturday) Issued at 252 AM CDT SUN APR 13 2014 Much colder air will be moving in on gusty northerly winds by Monday morning. The main trough will be moving through the area by the midday and early afternoon hours. Monday will be a shock compared to the nice warm weather this weekend. Cloudy and dreary conditions with north winds gusting up to 35 mph...off and on rain showers with temperatures falling most of the day into the middle and upper 30s...Wind chills will be in the 20s. There is still indications from the models and forecast soundings that enough cold air aloft will be available for either some wet snow mixing in or changing over by late morning to midday on Monday. The better potential for seeing wet snow falling will be along and north of the I-44 corridor and the higher elevations of the Ozark Plateau. No accumulations are expected with the warm ground temperatures and the air temperatures will be in the middle to upper 30s. Skies will clear from west to east Monday evening and temperatures will continue to drop as the Canadian high pressure moves in. There is high confidence that most of the area will see temperatures in the middle to upper 20s Monday night into Tuesday morning. Some patchy to areas of frost may occur if the wind relax enough and in sheltered areas. Will go ahead and issue a Freeze Watch area wide for Monday night. Temperatures will slowly moderate through the middle of the week. May see another round of frost and near freezing temperatures Tuesday night into Wednesday morning. Temperatures will be near seasonable averages by Thursday before another trough and cold front moves through and briefly cools temperatures back down for the end of the week. A good chance of showers will accompanying the cold front late Thursday into Friday. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 640 AM CDT SUN APR 13 2014 Pilots can expect deteriorating flight conditions today into tonight. VFR ceilings and scattered showers will prevail through midday with some areas of MVFR ceilings. Gusty southerly winds will continue through the day with frequent gusts over 25 kts. Low level wind shear will persist early this morning. Showers and thunderstorms will increase from the west late this afternoon into the this evening ahead of advancing cold front. Some of the storms along the front could be strong to possibly severe. MVFR to IFR conditions along with a wind shift to the northwest will follow the frontal passage this evening. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FREEZE WATCH from Monday evening through Tuesday morning FOR MOZ055>058-066>071-077>083-088>098-101>106. KS...FREEZE WATCH from Monday evening through Tuesday morning FOR KSZ073-097-101. && $$ UPDATE...Runnels SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Foster
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1207 AM CDT Sun Apr 13 2014 .MESOSCALE DISCUSSION... Issued at 1121 PM CDT SAT APR 12 2014 Cooling of the boundary layer is causing storms to transition to an elevated nature which is making the effects of the dry warm layer year 800 hPa even more pronounced. This resulted in a quick dissipation of any storms near or south of I-70 where the capping inversion is strongest and these areas are likely to remain dry overnight. Further north, intensifying LLJ is aiding the progression of strong storms between STJ and MCI where there remains MUCAPE of over 1000 J/kg. However this elevated instability is progged to weaken to the east of I-35 so the threat for strong storms will diminish as storms push into this less unstable airmass. && .SHORT TERM...(This Evening through Monday Night) Issued at 408 PM CDT SAT APR 12 2014 Tonight: Frontal boundaries will likely be the focus for most of the convection tonight. A warm front extends from a weak low near OMA through northern IL. A diffuse area of low pressure over southwest KS is connected to the OMA low by a very weak cold front. Strong and gusty southerly winds have pulled up the season`s first large swath of gulf moisture into KS/MO as noted by 60ish dewpoints while southwesterly h8 winds spread an elevated mixed layer across KS and MO resulting in a moderately strong cap.The end result is the warmest temperatures of the year with MLCAPEs around 2500 J/kg but marginal 0-6km shear around 35 kts. Evening convective activity will likely be closely tied to the IA warm front. Best severe threat will reside over IA with isolated severe storms possible over northwest MO mainly this evening. Large hail would be the most likely severe threat. A h7 shortwave is progged to lift northeast through northern KS/NE and activate this warm front. Last 4-5 runs of the HRRR has consistently shown scattered convection popping up along this boundary around 22z. The convection further south which the HRRR and RAP develop over east central KS is a bit suspicious as it forms within the well capped environment with no boundary nearby. Wouldn`t be surprised if it actually form further west along the dryline over central KS where some cu has recently formed. Prefer to limit the evening convection to northwest and north central MO. Also have low confidence in the NAM and GFS propagating an MCS southward into east central KS and west central MO by 06Z. Overall, will concentrate highest PoPs across northern MO and lower them south of the MO River. Sunday-Sunday night: A broad upper trough over the desert southwest is expected to lift northeast on Sunday and enhance the downstream lift via increasing/expanding upper level diffluence. This in turn will lead to widespread convection with heavy rains likely. Scattered convection will likely be ongoing Sunday morning and this plus extensive low level cloud cover will make it difficult to realize the moderate instability the soundings show. Should some breaks occur of any meaningful length of time then we could tap into this instability and give a boost to our severe threat. For now strong storms are possible south of the MO River on Sunday with a minimal severe threat. The main weather threat will be from heavy rains due to very efficient deep, tropical-like convection, which could train during the afternoon and early evening. The true cold front currently lies form eastern ND through west central SD which will reinforce the frontal boundary on Sunday. A second and much deeper northern upper trough will push this front southeast with strong cold air advection rushing in Sunday night. Inspection of Bufr soundings suggest the rain could mix with snow over parts of northwest MO late Sunday night. Monday-Monday night: A very raw and blustery day with temperatures 20 degrees below average. While the NAM had previously been discounted as being too cold and generating several inches of snow the latest GFS and ECMWF have been trending colder and also generating at least a rain/snow mix. Started trending colder yesterday and continue doing so today. Areas of light rain mixed with snow seems plausible if not likely Monday morning. Will hold off on mentioning any snow amounts for now. Very cold temperatures will settle in overnight Monday as skies clear out. Will see sub-freezing temperatures everywhere with many locations experiencing several hours of temperatures below 28F at which water freezes inside most plants. Will be issuing headlines eventually for Monday night/Tuesday morning. .LONG TERM...(Tuesday through Saturday) Issued at 408 PM CDT SAT APR 12 2014 Tuesday-Saturday After a chilly start Tuesday morning, temperatures will steadily rebound Tuesday into Wednesday, with highs primarily in the 50s and 60s respectively. Model solutions vary greatly with regards to timing, amplification/strength, and placement of the next upper trough to affect the area Thursday or Friday. This provides relatively high uncertainty to the expected weather during this period, and likewise the degree of cooler weather to follow upon the frontal passage. As for temperatures during the period, readings should remain slightly below climatological normals for this time of year. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1206 AM CDT SUN APR 13 2014 Storms should remain north and east of the KC and STJ areas for the remainder of the night. Earlier storms left winds variable but they should return from the SSE over the next several hours. MVFR ceilings developing over TX should rapidly expand northward early Sunday morning and could make it as far north as northern MO by sunrise. Widespread thunderstorms are likely beginning early Sunday afternoon as a cold front moves in. Some of these may be strong. Front will push through the area toward 00Z with some gusty winds and showers lingering through the evening. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...MJ LONG TERM...Blair AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1122 PM CDT Sat Apr 12 2014 .MESOSCALE DISCUSSION... Issued at 1121 PM CDT SAT APR 12 2014 Cooling of the boundary layer is causing storms to transition to an elevated nature which is making the effects of the dry warm layer year 800 hPa even more pronounced. This resulted in a quick dissipation of any storms near or south of I-70 where the capping inversion is strongest and these areas are likely to remain dry overnight. Further north, intensifying LLJ is aiding the progression of strong storms between STJ and MCI where there remains MUCAPE of over 1000 J/kg. However this elevated instability is progged to weaken to the east of I-35 so the threat for strong storms will diminish as storms push into this less unstable airmass. && .SHORT TERM...(This Evening through Monday Night) Issued at 408 PM CDT SAT APR 12 2014 Tonight: Frontal boundaries will likely be the focus for most of the convection tonight. A warm front extends from a weak low near OMA through northern IL. A diffuse area of low pressure over southwest KS is connected to the OMA low by a very weak cold front. Strong and gusty southerly winds have pulled up the season`s first large swath of gulf moisture into KS/MO as noted by 60ish dewpoints while southwesterly h8 winds spread an elevated mixed layer across KS and MO resulting in a moderately strong cap.The end result is the warmest temperatures of the year with MLCAPEs around 2500 J/kg but marginal 0-6km shear around 35 kts. Evening convective activity will likely be closely tied to the IA warm front. Best severe threat will reside over IA with isolated severe storms possible over northwest MO mainly this evening. Large hail would be the most likely severe threat. A h7 shortwave is progged to lift northeast through northern KS/NE and activate this warm front. Last 4-5 runs of the HRRR has consistently shown scattered convection popping up along this boundary around 22z. The convection further south which the HRRR and RAP develop over east central KS is a bit suspicious as it forms within the well capped environment with no boundary nearby. Wouldn`t be surprised if it actually form further west along the dryline over central KS where some cu has recently formed. Prefer to limit the evening convection to northwest and north central MO. Also have low confidence in the NAM and GFS propagating an MCS southward into east central KS and west central MO by 06Z. Overall, will concentrate highest PoPs across northern MO and lower them south of the MO River. Sunday-Sunday night: A broad upper trough over the desert southwest is expected to lift northeast on Sunday and enhance the downstream lift via increasing/expanding upper level diffluence. This in turn will lead to widespread convection with heavy rains likely. Scattered convection will likely be ongoing Sunday morning and this plus extensive low level cloud cover will make it difficult to realize the moderate instability the soundings show. Should some breaks occur of any meaningful length of time then we could tap into this instability and give a boost to our severe threat. For now strong storms are possible south of the MO River on Sunday with a minimal severe threat. The main weather threat will be from heavy rains due to very efficient deep, tropical-like convection, which could train during the afternoon and early evening. The true cold front currently lies form eastern ND through west central SD which will reinforce the frontal boundary on Sunday. A second and much deeper northern upper trough will push this front southeast with strong cold air advection rushing in Sunday night. Inspection of Bufr soundings suggest the rain could mix with snow over parts of northwest MO late Sunday night. Monday-Monday night: A very raw and blustery day with temperatures 20 degrees below average. While the NAM had previously been discounted as being too cold and generating several inches of snow the latest GFS and ECMWF have been trending colder and also generating at least a rain/snow mix. Started trending colder yesterday and continue doing so today. Areas of light rain mixed with snow seems plausible if not likely Monday morning. Will hold off on mentioning any snow amounts for now. Very cold temperatures will settle in overnight Monday as skies clear out. Will see sub-freezing temperatures everywhere with many locations experiencing several hours of temperatures below 28F at which water freezes inside most plants. Will be issuing headlines eventually for Monday night/Tuesday morning. .LONG TERM...(Tuesday through Saturday) Issued at 408 PM CDT SAT APR 12 2014 Tuesday-Saturday After a chilly start Tuesday morning, temperatures will steadily rebound Tuesday into Wednesday, with highs primarily in the 50s and 60s respectively. Model solutions vary greatly with regards to timing, amplification/strength, and placement of the next upper trough to affect the area Thursday or Friday. This provides relatively high uncertainty to the expected weather during this period, and likewise the degree of cooler weather to follow upon the frontal passage. As for temperatures during the period, readings should remain slightly below climatological normals for this time of year. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 632 PM CDT SAT APR 12 2014 Line of convection developing across cntrl KS will remain north and west of KC for much of the night. There is a chance that additional storms could develop closer to MCI around 09Z...but better chances appear to be just to the north near STJ so thunder was kept out of the KC terminals for now. Will keep a close eye in case thunder needs to be added later on. Widespread rain and thunderstorms likely on Sunday with a cold front moving into the region. Trends have slowed down the timing of this front and attendant thunderstorms to the early afternoon hours for the KC area. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ MESOSCALE...Hawblitzel SHORT TERM...MJ LONG TERM...Blair AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
331 PM CDT SUN APR 13 2014 .SHORT TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 220 PM CDT SUN APR 13 2014 PRIMARY FORECAST CONCERN WILL BE WITH THE FIRST 12 HOURS OF THE FORECAST AND ITS VARIETY OF WEATHER ACROSS THE AREA. COLDER AIR CONTINUES ITS SLOW ADVANCE INTO EASTERN NEBRASKA AT 19Z WITH SNOW NOW FALLING ACROSS NORTHEAST NEBRASKA WEST OF A COLUMBUS TO SIOUX CITY LINE. SHORT RANGE MODELS SUCH AS THE HRRR SUGGEST MAIN ORIENTATION OF THE SNOW BAND WILL GENERALLY SETUP IN AN AREA BOUNDED BY COLUMBUS TO TEKAMAH ON THE SOUTH AND YANKTON TO NELIGH ON THE NORTH THROUGH THE REMAINDER OF THE AFTERNOON AS MID LEVEL CLOSED LOW TRACKS EAST INTO CENTRAL IOWA. SNOW THEN SPREADS EAST AND ENDS FROM THE WEST DURING THE EVENING ACROSS THE REMAINDER OF EASTERN NEBRASKA AND SOUTHWEST IOWA AS THE MID LEVEL LOW CONTINUES TO LIFT TOWARD THE GREAT LAKES REGION AND THE SURFACE LOW MOVES INTO NORTHERN ILLINOIS. EXPECT SNOW TO END SHORTLY AFTER MIDNIGHT IN THE FAR SOUTHEAST CORNER OF THE FORECAST AREA. WILL LIKELY EXPAND WINTER WEATHER ADVISORY ACROSS THIS AREA THROUGH THE 00Z TIME FRAME IN LINE WITH EXPECTED SNOW. CURRENT INDICATIONS ARE FOR 1 TO 3 INCH ACCUMULATIONS BY EVENING IN THE ADVISORY AREA WITH AN INCH OR LESS ELSEWHERE THROUGH THE EVENING. WILL ALSO EXPAND WIND ADVISORY ACROSS REMAINDER OF SOUTHEAST NEBRASKA AND SOUTHWEST IOWA AND EXTEND THROUGH 03Z. WEATHER CONDITIONS IMPROVE FOR THE AREA AFTER TONIGHT ALTHOUGH TEMPERATURES WILL BE ON THE COOL SIDE MONDAY. ANOTHER CLIPPER MOVES INTO THE NORTHERN PLAINS TUESDAY WITH WARMER AIR RETURNING TO THE AREA IN ADVANCE OF THIS SYSTEM. COLD FRONT THEN MOVES SOUTH INTO THE AREA ON WEDNESDAY WITH ANOTHER CHANCE OF RAIN OR SNOW. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 220 PM CDT SUN APR 13 2014 COOL AND WET START TO THE EXTENDED PERIOD AS PREVIOUSLY MENTIONED COLD FRONT MOVES SOUTH OF THE AREA WITH ANOTHER COLD UPPER TROUGH DEVELOPING OVER THE CENTRAL PART OF THE COUNTRY. DAY TO DAY WARMING FOLLOWS THIS SYSTEM FOR FRIDAY THROUGH SUNDAY && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1222 PM CDT SUN APR 13 2014 SCATTERED THUNDERSTORMS REMAINED OVER SERN NEBR AT TAF ISSUANCE TIME ALTHOUGH WOULD EXPECT ACTIVITY TO BECOME MORE FOCUSED SE OF KLNK/KOMA BY 2 OR 3 PM CDT. OTHERWISE STRONG NNE SURFACE WINDS WILL PREVAIL INTO THIS EVENING BEFORE DECREASING. COLDER AIR SPREADING SE INTO ERN NEBRASKA WILL LIKELY TURN RAIN TO A RAIN/SNOW MIX TO NERN NEBR...INCLUDING KOFK...WITH A PERIOD OF SNOW LIKELY LATER THIS AFTN INTO EARLY EVENING BEFORE PRECIP ENDS. DUE TO ONGOING INSTABILITY OVER THE AREA THIS AFTERNOON...THERE COULD ALSO BE SLEET MIXED IN WITH SOME OF THE PRECIP THROUGH MID AFTN AS WELL. COLDER AIR SHOULD ALSO BRING A PERIOD OF RAIN/SNOW MIX AT KOMA AND KLNK THIS EVENING...IF NOT A PERIOD OF JUST SNOW...BEFORE PRECIP ENDS AT THOSE 2 SITES LATE THIS EVENING OR EARLY TONIGHT. IN GENERAL IFR OR NEAR IFR CONDITIONS EXPECTED IN PRECIP BEFORE CIGS IMPROVE A FEW HOURS AFTER PRECIP ENDS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NEZ015>018-030>034- 042>045-050>053-065>068-078-088>093. WINTER WEATHER ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ015>018-030>034-042>045. IA...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ043-055-056-069- 079-080-090-091. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...CHERMOK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
123 PM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 122 PM CDT SUN APR 13 2014 ALLOWED THE WINTER WEATHER ADVISORY TO EXPIRE FOR SHERIDAN AND WESTERN CHERRY COUNTIES AS ONLY LIGHT SNOW REMAINS IN THOSE AREAS. REPORTS FROM THAT AREA INDICATE AMOUNTS UP TO 3 INCHES HAVE FALLEN AND WINDS ARE CAUSING SOME LOCALIZED BLOWING SNOW. THIS SHOULD IMPROVE THROUGH THE AFTERNOON. THE PRIMARY BAND OF SNOW HAS SHIFTED EAST AND IS NOW GENERALLY SOUTH AND EAST OF A LINE FROM OGALLALA TO THEDFORD. THE LATEST MESOSCALE MODELS HAD LATCHED ON TO THAT AND THE TREND IN THE MODELS IS FOR THE SNOW TO CONTINUE SINKING TO THE SOUTH AND EAST THROUGH THE AFTERNOON AS THE WHOLE SYSTEM MOVES EAST. ADDITIONAL COUNTIES OVER THE PANHANDLE AND WESTERN SANDHILLS WILL LIKELY BE CANCELLED EARLY IN THE NEXT SEVERAL HOURS AS CONDITIONS ARE CONFIRMED TO HAVE IMPROVED. UPDATE ISSUED AT 920 AM CDT SUN APR 13 2014 FORECAST WAS UPDATED TO COOL HOURLY TEMPERATURES A BIT QUICKER THAN WAS ORIGINALLY EXPECTED AS WELL AS TO INCREASE PRECIPITATION CHANCES THROUGHOUT THE DAY AS SNOW AND RAIN IS ONGOING. AT THE SURFACE...THE FREEZING LINE WAS ROUGHLY FROM KSNY TO KTIF TO KANW...HOWEVER LAPS SOUNDINGS SHOW THAT THE AIR ALOFT HAS COOLED SO MOST OF THE AREA SHOULD ONLY SEE SNOW FALLING ALTHOUGH WHERE IT IS WARMER IT MAY MELT ON CONTACT. THIS IS ALSO BEING CONFIRMED BY DUAL-POL RADAR AS THERE IS A CC DISCONTINUITY FROM AROUND KIML TO KLBF TO KONL...SO EITHER A MIX OR RAIN IS CURRENTLY FALLING SOUTH AND EAST OF THIS LINE. UPDATE ISSUED AT 720 AM CDT SUN APR 13 2014 THUNDERSTORMS HAVE BEEN SLOWLY INCREASING ACROSS THE WFO GID FCST AREA THIS MORNING AND NOW ARE DEVELOPING WEST THROUGH THE WFO GLD FCST AREA...AIMED AT SWRN NEB. SO THIS UPDATE IS FOR THE ISOLATED STORMS. NOTE THE RAP MAINTAINS NEGATIVE LIFTED INDICES WELL EAST OF THIS AREA OF DEVELOPMENT SO THIS IS AN UNEXPECTED BUT THEY APPEAR TO BE ASSOCIATED WITH A DEVELOPING DEFORMATION ZONE ACROSS THE SANDHILLS WHICH THE LATEST RAP IS INTENSIFYING THIS MORNING BEFORE OUR SECOND HEAVY SNOW BAND DEVELOPS ACROSS SCNTL NEB THIS AFTERNOON. UPDATE ISSUED AT 713 AM CDT SUN APR 13 2014 NEDOR CAMS IN SHERIDAN COUNTY INDICATE HEAVY BLOWING SNOW IN SPOTS WITH REDUCED VISIBILITY AND SNOW COVERED ROADS. THE HRRR SUGGESTS SNOW THROUGH 15Z SO A WINTER WEATHER ADVISORY IS IN PLACE THERE AND IN WRN CHERRY COUNTY UNTIL 18Z...GIVEN THE LATEST RADAR TRENDS IN CHERRY COUNTY AND TEMPERATURES IN THE UPPER 20S AT KIEN. UPDATE ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 122 PM CDT SUN APR 13 2014 IFR/LIFR CONDITIONS WILL BE IN PLACE FOR KLBF THROUGH A PORTION OF THE AFTERNOON AS SNOW FALLS ACROSS THE AREA. THE STORM SYSTEM BRINGING THE SNOW WILL MOVE EAST OVER THE NEXT 24 HOURS SO ONCE THE SNOW ENDS CONDITIONS WILL IMPROVE. LIGHT SNOW WILL CONTINUE TO FALL AFTER THE MAIN BAND OF SNOW MOVES OUT OF THE AREA...KEEPING VISIBILITIES AT MVFR FOR A FEW HOURS. BY 00Z...BOTH KVTN AND KLBF ARE EXPECTED TO BE MVFR OR BETTER...WITH VFR BY 03Z. WINDS WILL ALSO STAY STRONG THROUGH THE AFTERNOON...AND WILL SLOWLY DIMINSISH THIS EVENING. AFTER 06Z...EXPECT NO FURTHER GUSTS BUT AS THE BOUNDARY LAYER MIXED MONDAY MORNING LOOK FOR GUSTS TO 20KTS AGAIN. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>029-035>038-056>059-069>071. WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR NEZ004-094. && $$ UPDATE...BROOKS SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...BROOKS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
929 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 920 AM CDT SUN APR 13 2014 FORECAST WAS UPDATED TO COOL HOURLY TEMPERATURES A BIT QUICKER THAN WAS ORIGINALLY EXPECTED AS WELL AS TO INCREASE PRECIPITATION CHANCES THROUGHOUT THE DAY AS SNOW AND RAIN IS ONGOING. AT THE SURFACE...THE FREEZING LINE WAS ROUGHLY FROM KSNY TO KTIF TO KANW...HOWEVER LAPS SOUNDINGS SHOW THAT THE AIR ALOFT HAS COOLED SO MOST OF THE AREA SHOULD ONLY SEE SNOW FALLING ALTHOUGH WHERE IT IS WARMER IT MAY MELT ON CONTACT. THIS IS ALSO BEING CONFIRMED BY DUAL-POL RADAR AS THERE IS A CC DISCONTINUITY FROM AROUND KIML TO KLBF TO KONL...SO EITHER A MIX OR RAIN IS CURRENTLY FALLING SOUTH AND EAST OF THIS LINE. UPDATE ISSUED AT 720 AM CDT SUN APR 13 2014 THUNDERSTORMS HAVE BEEN SLOWLY INCREASING ACROSS THE WFO GID FCST AREA THIS MORNING AND NOW ARE DEVELOPING WEST THROUGH THE WFO GLD FCST AREA...AIMED AT SWRN NEB. SO THIS UPDATE IS FOR THE ISOLATED STORMS. NOTE THE RAP MAINTAINS NEGATIVE LIFTED INDICES WELL EAST OF THIS AREA OF DEVELOPMENT SO THIS IS AN UNEXPECTED BUT THEY APPEAR TO BE ASSOCIATED WITH A DEVELOPING DEFORMATION ZONE ACROSS THE SANDHILLS WHICH THE LATEST RAP IS INTENSIFYING THIS MORNING BEFORE OUR SECOND HEAVY SNOW BAND DEVELOPS ACROSS SCNTL NEB THIS AFTERNOON. UPDATE ISSUED AT 713 AM CDT SUN APR 13 2014 NEDOR CAMS IN SHERIDAN COUNTY INDICATE HEAVY BLOWING SNOW IN SPOTS WITH REDUCED VISIBILITY AND SNOW COVERED ROADS. THE HRRR SUGGESTS SNOW THROUGH 15Z SO A WINTER WEATHER ADVISORY IS IN PLACE THERE AND IN WRN CHERRY COUNTY UNTIL 18Z...GIVEN THE LATEST RADAR TRENDS IN CHERRY COUNTY AND TEMPERATURES IN THE UPPER 20S AT KIEN. UPDATE ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 IFR/LOCAL LIFR FROM BIG SPRINGS TO BREWSTER WILL PROPAGATE SOUTH AND EAST TODAY AND EXIT THE FCST AREA AROUND 00Z. VFR IS EXPECTED THEREAFTER. WINDS TODAY 36027G40KT DIMINISH THIS EVENING AROUND SUNSET. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>029-035>038-056>059-069>071. WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR NEZ004-094. && $$ UPDATE...BROOKS SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
727 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 720 AM CDT SUN APR 13 2014 THUNDERSTORMS HAVE BEEN SLOWLY INCREASING ACROSS THE WFO GID FCST AREA THIS MORNING AND NOW ARE DEVELOPING WEST THROUGH THE WFO GLD FCST AREA...AIMED AT SWRN NEB. SO THIS UPDATE IS FOR THE ISOLATED STORMS. NOTE THE RAP MAINTAINS NEGATIVE LIFTED INDICES WELL EAST OF THIS AREA OF DEVELOPMENT SO THIS IS AN UNEXPECTED BUT THEY APPEAR TO BE ASSOCIATED WITH A DEVELOPING DEFORMATION ZONE ACROSS THE SANDHILLS WHICH THE LATEST RAP IS INTENSIFYING THIS MORNING BEFORE OUR SECOND HEAVY SNOW BAND DEVELOPS ACROSS SCNTL NEB THIS AFTERNOON. UPDATE ISSUED AT 713 AM CDT SUN APR 13 2014 NEDOR CAMS IN SHERIDAN COUNTY INDICATE HEAVY BLOWING SNOW IN SPOTS WITH REDUCED VISIBILITY AND SNOW COVERED ROADS. THE HRRR SUGGESTS SNOW THROUGH 15Z SO A WINTER WEATHER ADVISORY IS IN PLACE THERE AND IN WRN CHERRY COUNTY UNTIL 18Z...GIVEN THE LATEST RADAR TRENDS IN CHERRY COUNTY AND TEMPERATURES IN THE UPPER 20S AT KIEN. UPDATE ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 IFR/LOCAL LIFR FROM BIG SPRINGS TO BREWSTER WILL PROPAGATE SOUTH AND EAST TODAY AND EXIT THE FCST AREA AROUND 00Z. VFR IS EXPECTED THEREAFTER. WINDS TODAY 36027G40KT DIMINISH THIS EVENING AROUND SUNSET. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 1 PM CDT /NOON MDT/ THIS AFTERNOON FOR NEZ004-022>029-035>038-056>059-069>071-094. && $$ UPDATE...CDC SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
717 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 713 AM CDT SUN APR 13 2014 NEDOR CAMS IN SHERIDAN COUNTY INDICATE HEAVY BLOWING SNOW IN SPOTS WITH REDUCED VISIBILITY AND SNOW COVERED ROADS. THE HRRR SUGGESTS SNOW THROUGH 15Z SO A WINTER WEATHER ADVISORY IS IN PLACE THERE AND IN WRN CHERRY COUNTY UNTIL 18Z...GIVEN THE LATEST RADAR TRENDS IN CHERRY COUNTY AND TEMPERATURES IN THE UPPER 20S AT KIEN. UPDATE ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 IFR/LOCAL LIFR FROM BIG SPRINGS TO BREWSTER WILL PROPAGATE SOUTH AND EAST TODAY AND EXIT THE FCST AREA AROUND 00Z. VFR IS EXPECTED THEREAFTER. WINDS TODAY 36027G40KT DIMINISH THIS EVENING AROUND SUNSET. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 1 PM CDT /NOON MDT/ THIS AFTERNOON FOR NEZ004-022>029-035>038-056>059-069>071-094. && $$ UPDATE...CDC SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
654 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 654 AM CDT SUN APR 13 2014 IFR/LOCAL LIFR FROM BIG SPRINGS TO BREWSTER WILL PROPAGATE SOUTH AND EAST TODAY AND EXIT THE FCST AREA AROUND 00Z. VFR IS EXPECTED THEREAFTER. WINDS TODAY 36027G40KT DIMINISH THIS EVENING AROUND SUNSET. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>029-035>038-056>059-069>071. && $$ UPDATE...CDC SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
539 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 539 AM CDT SUN APR 13 2014 SFC WINDS HAVE INCREASED TO 30 MPH OR STRONGER THIS HOUR AND SNOW IS UNDERWAY AT THEDFORD AND WEST THROUGH THE PANHANDLE SO THE WINTER WEATHER ADVISORY IS IN EFFECT NOW THROUGH 7 PM CDT. THE 09Z RAP MODEL WHICH SUCCESSFULLY PREDICTED THE SNOW BAND DEVELOPING ACROSS THE CNTL SANDHILLS SWINGS THIS BAND SOUTH THROUGH LINCOLN COUNTY AND MERGES IT THIS AFTN WITH A NEW BAND DEVELOPING FROM KLXN TO KODX...A BIT EAST OF THE 07Z-08Z RUNS. THE SNOW FORECAST APPEARS TO BE GENERALLY ON TRACK AND THE QPF RATES IN THE 09Z MODEL RUN INDICATE 1 TO 2 INCH PER HOUR RATES. UPDATE ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1222 AM CDT SUN APR 13 2014 A STRONG UPPER LEVEL TROUGH OF LOW PRESSURE WILL TRACK ACROSS THE CENTRAL PLAINS OVER THE NEXT 24 HOURS. THIS WILL LEAD TO THE DEVELOPMENT OF RAIN SHOWERS AND SNOW ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA INTO THE OVERNIGHT HOURS AND ON SUNDAY. FOR THE KLBF TERMINAL...VFR CIGS ARE EXPECTED THROUGH SUNRISE SUNDAY WITH CIGS RANGING FROM 5000 TO 10000 FT AGL. CIGS WILL LOWER TO MVFR AFTER 13Z AND REMAIN THERE THROUGH 03Z MONDAY. RAIN AND SNOW SHOWERS WILL DEVELOP SUNDAY MORNING...WITH A CHANGEOVER TO ALL SNOW BY LATE MORNING. VISBYS MAY DROP DOWN TO 1SM WITH CIGS AROUND 1000 FT AGL BY LATE MORNING...AND WILL PERSIST THROUGH THE LATE AFTERNOON HOURS ON SUNDAY. FLT CONDS WILL IMPROVE GREATLY BY 00Z MONDAY WITH VFR CIGS EXPECTED AFTER 03Z MONDAY. FOR THE KVTN TERMINAL...MVFR CIGS WILL DEVELOP AFTER 11Z SUNDAY AND WILL PERSIST THROUGH MID AFTERNOON SUNDAY. LIGHT RAIN OR SNOW SHOWERS ARE LIKELY OVERNIGHT TONIGHT THROUGH MIDDAY SUNDAY. VISBYS MAY DROP AS LOW AS 2SM...ESPECIALLY DURING THE EARLY TO MID MORNING HOURS SUNDAY. VFR CIGS WILL RETURN BY MID AFTERNOON WITH CIGS RANGING FROM 8000 TO 12000 FT AGL AFTER 22Z SUNDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>029-035>038-056>059-069>071. && $$ UPDATE...CDC SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
423 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 422 AM CDT SUN APR 13 2014 THE 08Z RAP AND 05Z HRRR ARE CONSISTENT WITH A HEAVY SNOW BAND DEVELOPING THIS AFTERNOON STRETCHING THROUGH FRONTIER...CUSTER AND WHEELER COUNTIES. THE FORECAST HAS BEEN UPDATED FOR THIS EXPECTED SNOWFALL AND THE ADDITION OF WHEELER COUNTY TO THE WINTER WEATHER ADVISORY. THE EXPECTED 4 INCH TOTALS IN THESE AREAS IS CONSISTENT THE THE LATEST SOLNS OF THE HRRR AND RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1222 AM CDT SUN APR 13 2014 A STRONG UPPER LEVEL TROUGH OF LOW PRESSURE WILL TRACK ACROSS THE CENTRAL PLAINS OVER THE NEXT 24 HOURS. THIS WILL LEAD TO THE DEVELOPMENT OF RAIN SHOWERS AND SNOW ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA INTO THE OVERNIGHT HOURS AND ON SUNDAY. FOR THE KLBF TERMINAL...VFR CIGS ARE EXPECTED THROUGH SUNRISE SUNDAY WITH CIGS RANGING FROM 5000 TO 10000 FT AGL. CIGS WILL LOWER TO MVFR AFTER 13Z AND REMAIN THERE THROUGH 03Z MONDAY. RAIN AND SNOW SHOWERS WILL DEVELOP SUNDAY MORNING...WITH A CHANGEOVER TO ALL SNOW BY LATE MORNING. VISBYS MAY DROP DOWN TO 1SM WITH CIGS AROUND 1000 FT AGL BY LATE MORNING...AND WILL PERSIST THROUGH THE LATE AFTERNOON HOURS ON SUNDAY. FLT CONDS WILL IMPROVE GREATLY BY 00Z MONDAY WITH VFR CIGS EXPECTED AFTER 03Z MONDAY. FOR THE KVTN TERMINAL...MVFR CIGS WILL DEVELOP AFTER 11Z SUNDAY AND WILL PERSIST THROUGH MID AFTERNOON SUNDAY. LIGHT RAIN OR SNOW SHOWERS ARE LIKELY OVERNIGHT TONIGHT THROUGH MIDDAY SUNDAY. VISBYS MAY DROP AS LOW AS 2SM...ESPECIALLY DURING THE EARLY TO MID MORNING HOURS SUNDAY. VFR CIGS WILL RETURN BY MID AFTERNOON WITH CIGS RANGING FROM 8000 TO 12000 FT AGL AFTER 22Z SUNDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>029-035>038-056>059-069>071. && $$ UPDATE...CDC SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
343 AM CDT SUN APR 13 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 308 AM CDT SUN APR 13 2014 THE 05Z RAP APPEARS TO BE LEADING THE MODEL PACK FOLLOWED BY THE HRRR AND THEN THE NAM DEVELOPING A FULL BLOWN SPRING SNOW STORM. WATER VAPOR AND THE RAP PV 1.0 SFC SUGGEST THE NRN AND SRN STREAM DISTURBANCES MAY PHASE THIS AFTERNOON. AS A RESULT...THE MODELS ARE COUPLING THE 850-700MB AND 700-500MB PETERSON FGEN ACROSS CNTL NEB THIS AFTN AND PRODUCING A HEAVY RAIN-SNOW BAND FROM ROUGHLY 50 MILES EITHER SIDE OF AN ARC FROM KHDE TO KBVN. THE NAM AND SREF ARE FARTHER WEST AND NORTH WELL INTO THE FCST AREA WHILE THE RAP AND HRRR ARE MOSTLY EAST OF THE FCST AREA IN CNTL NEB. THE FORECAST FOLLOWS 50 PERCENT OF THE PREVIOUS FORECAST AND 50 PERCENT OF THE 05Z RAP...WHICH IS RUN EVERY HOUR. THE 07Z RAP HAS SHIFTED THE HEAVIEST QPF...1.5 INCHES...BACK WEST INTO EASTERN FRONTIER AND CUSTER COUNTIES. REGARDLESS...THE FORECAST PRODUCES 1 TO 4 INCHES OF SNOW GENERALLY ACROSS WRN NEB...SRN NEB AND CUSTER COUNTY TODAY BUT ERRORS COULD BE LARGE IN THESE TYPES OF EVENTS. THE STAKES ARE QUITE HIGH WITH THIS ONE AS A 30-50 KT BARRIER JET DEVELOPS FROM 850-750MB NEAR OR JUST EAST OF THE FCST AREA. 30 TO 35 MPH SFC WINDS SHOULD DEVELOP UNDER THAT JET AND EXTEND WEST THROUGH LINCOLN COUNTY. THE WIND ADVISORY HAS BEEN REPLACED WITH A WINTER WEATHER ADVISORY. THE RAP AND HRRR SHOW THE RAIN BAND ACROSS NRN NEB DECAYING EARLY THIS MORNING FOLLOWED BY THE FORMATION OF A SECOND HEAVIER SNOW BAND ACROSS THE CNTL SANDHILLS AND SWRN NEB TO BE FOLLOWED BY A THIRD AND HEAVIER RAIN-SNOW BAND ACROSS CNTL NEB THIS AFTERNOON. THE LATTER TWO BANDS ARE BELIEVED TO BE CAPABLE OF PRODUCING SNOWFALL RATES IN EXCESS OF 1 INCH PER HOUR AND THE 07Z RAP INDICATES 3 INCHES PER HOUR ACROSS SERN CUSTER AND ERN FRONTIER COUNTIES. TEMPERATURES TODAY FALL MOST OF THE DAY ACCORDING TO THE MODEL CONSENSUS AND EVEN BELOW FREEZING ACROSS THE NORTHWEST. THERE IS NO CHANGE TO THE TEMPERATURE FORECAST FOR TONIGHT WITH LOWS IN THE 20S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 308 AM CDT SUN APR 13 2014 COLD TEMPERATURES WILL BE THE STORY MONDAY...AS A BATCH OF LATE SEASON ARCTIC AIR OOZES SOUTH INTO THE PLAINS BEHIND THE DEPARTING STORM SYSTEM. H85 TEMPERATURES WILL GRADUALLY WARM THROUGH THE DAY...AS THE FLOW ALOFT SHIFTS FROM NORTH DURING THE MORNING TO NORTHWEST BY AFTERNOON. DESPITE THE SLIGHT WARMING ALOFT...HIGHS WILL ONLY BE IN THE 40S AREA WIDE...ALONG WITH NORTHWEST WINDS 10 TO 20 MPH. IF A BAND OF HEAVY SNOW MATERIALIZES TODAY...THEN HIGHS MAY ONLY REACH THE 30S WHERE THE SNOW FALLS. HIGH PRESSURE RIDGE AXIS SHIFTS EAST OF THE AREA TUESDAY...WITH MUCH WARMER AIR ADVECTING NORTHEAST INTO THE AREA. SHOULD SEE HIGHS INTO THE 60S AT MOST LOCATIONS. THE NEXT SYSTEM...WHICH MODELS HAVE BEEN STRUGGLING WITH...ARRIVES WEDNESDAY NIGHT INTO THURSDAY. THE TREND IS FOR A WEAKER LESS AMPLIFIED SYSTEM. UNTIL THE MODELS CONVERGE ON AN OVERALL SOLUTION...WILL CONTINUE TO BLANKET THE AREA WITH LOW POPS OF 20 TO 40 PERCENT. THE BEST CHANCE FOR PRECIPITATION AT THIS POINT LOOKS TO BE IN SOUTHWEST NEBRASKA...WHERE THE HIGHER 40 POPS RESIDE. OTHERWISE MORE COLD AIR WILL BE DRAWN SOUTH...BUT HERE TOO MODELS DIFFER ON JUST HOW MUCH COLD AIR. THE GFS IS THE COLDEST...BUT IT HAS ALSO BEEN THE MOST AMPLIFIED AND IS NOW BACKING OFF. THE ECMWF HAS JUST A GLANCING BLOW OF COLD AIR THURSDAY...WITH A QUICK WARM UP FRIDAY INTO SATURDAY. WILL CONTINUE TO MONITOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1222 AM CDT SUN APR 13 2014 A STRONG UPPER LEVEL TROUGH OF LOW PRESSURE WILL TRACK ACROSS THE CENTRAL PLAINS OVER THE NEXT 24 HOURS. THIS WILL LEAD TO THE DEVELOPMENT OF RAIN SHOWERS AND SNOW ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA INTO THE OVERNIGHT HOURS AND ON SUNDAY. FOR THE KLBF TERMINAL...VFR CIGS ARE EXPECTED THROUGH SUNRISE SUNDAY WITH CIGS RANGING FROM 5000 TO 10000 FT AGL. CIGS WILL LOWER TO MVFR AFTER 13Z AND REMAIN THERE THROUGH 03Z MONDAY. RAIN AND SNOW SHOWERS WILL DEVELOP SUNDAY MORNING...WITH A CHANGEOVER TO ALL SNOW BY LATE MORNING. VISBYS MAY DROP DOWN TO 1SM WITH CIGS AROUND 1000 FT AGL BY LATE MORNING...AND WILL PERSIST THROUGH THE LATE AFTERNOON HOURS ON SUNDAY. FLT CONDS WILL IMPROVE GREATLY BY 00Z MONDAY WITH VFR CIGS EXPECTED AFTER 03Z MONDAY. FOR THE KVTN TERMINAL...MVFR CIGS WILL DEVELOP AFTER 11Z SUNDAY AND WILL PERSIST THROUGH MID AFTERNOON SUNDAY. LIGHT RAIN OR SNOW SHOWERS ARE LIKELY OVERNIGHT TONIGHT THROUGH MIDDAY SUNDAY. VISBYS MAY DROP AS LOW AS 2SM...ESPECIALLY DURING THE EARLY TO MID MORNING HOURS SUNDAY. VFR CIGS WILL RETURN BY MID AFTERNOON WITH CIGS RANGING FROM 8000 TO 12000 FT AGL AFTER 22Z SUNDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 7 AM CDT /6 AM MDT/ THIS MORNING TO 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ022>028-035>038-056>059- 069>071. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1206 AM CDT SUN APR 13 2014 .UPDATE... ISSUED AT 1156 PM CDT SAT APR 12 2014 HAVE CANCELED SEVERE WATCH FOR SOUTHWEST IOWA BUT HAVE KEPT THREE FAR SOUTHEAST NEBRASKA COUNTIES IN WATCH 71 AS A PESKY STORM MIGRATES ACROSS THE BORDER. THIS ONE APPEARS AS THOUGH IT WILL STAY JUST BELOW SEVERE WITH SMALL HAIL AND SOME LOCALLY HEAVY RAIN...BUT COULD PULSE UP AS LOW LEVEL JET STRENGTHENS. OTHERWISE PRECIPITATION HAS ENDED ACROSS MOST OF THE CWA. LATEST RUNS OF RAP AND HRRR STILL SUGGEST A LULL IN ACTIVITY FOR A FEW HOURS BEFORE ELEVATED FRONTAL BOUNDARY LIGHTS UP IN AROUND 4 OR 5 AM IN A LINE FROM RED OAK TO LINCOLN. SEVERE PROBABILITIES DECREASE WITH THIS LINE...BUT HAIL IS STILL POSSIBLE. EXPANSION TO THE NORTH THEN ENSUES THROUGH THE MORNING. UPDATE ISSUED AT 952 PM CDT SAT APR 12 2014 CONVECTION HAS PUSHED EAST OF OUR WESTERN IOWA COUNTIES JUST BEFORE 10 PM. SURFACE LOW AND UPPER WAVE HELPED TO INTENSIFY STORMS THERE EARLIER IN THE EVENING WITH SOME REPORTS OF GOLF BALL HAIL. SEVERE WATCH FOR WEST CENTRAL IOWA WAS CANCELLED JUST BEFORE 10 PM EXPIRATION WITH A NEW WATCH ISSUED EAST OF OUR AREA. STILL HAVE FAR SOUTHEAST NEBRASKA AND A FEW SOUTHWEST IOWA COUNTIES IN A WATCH THROUGH 2 AM. RADAR TRENDS FROM NORTHEAST KANSAS CONVECTION SUGGEST STORMS THERE WILL STAY SOUTH OF SOUTHEAST NEBRASKA. HOWEVER THOSE STORMS ARE ONLY A COUNTY AWAY AND EARLIER CONVECTION PRODUCED FAST-MOVING LEFT MOVER THAT DROPPED LARGE HAIL IN FALLS CITY. THUS WILL MAINTAIN WATCH AT LEAST FOR A COUPLE MORE HOURS IN SOUTHEAST NEBRASKA. SOUTHWEST IOWA COUNTIES MAY BE A DIFFERENT STORY AS STORMS HAVE MOVED EAST AND LIKELIHOOD OF REDEVELOPMENT TO THE WEST OVER THE NEXT SEVERAL HOURS IS WANING. WILL RE-EVALUATE THIS IN THE NEXT HOUR OR SO. SHORT RANGE MESOSCALE MODELS ARE STILL SUGGESTING THERE MAY BE A BREAK IN CONVECTIVE ACTIVITY UNTIL LATER TONIGHT WHEN LOW LEVEL JET STRENGTHENS AND OVERRIDES SOUTHWARD MOVING COLD FRONT. WOULD EXPECT THAT ACTIVITY TO START LIGHTING UP NEAR OR AFTER 4 AM ALONG AND SOUTH OF INTERSTATE 80 AND EXPAND NORTH THROUGH SUNRISE. && .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 300 PM CDT SAT APR 12 2014 CONVECTIVE TRENDS TONIGHT AND PRECIPITATION COVERAGE/TYPE SUNDAY PRIMARY CONCERN IN SHORT TERM. WEAK WIND SHIFT/FRONT CONTINUED TO PRESS SEWD INTO THE AFTN EXTENDING FROM NEAR HARLAN IA TO A LITTLE SE OF OLU AT 20Z...ALTHOUGH BETTER SFC COOLING LAGGED WELL TO THE NORTH. MOST OF THE AREA IN ADVANCE OF WIND SHIFT HAS HAD ENOUGH OF A SW COMPONENT TO WIND THAT IT HAD COMBINED WITH MIXING TO LOWER MANY SFC DWPTS INTO MID 50S OR LOWER...MAIN EXCEPTION THROUGH 20Z FROM SE CORNER OF NEBR INTO SW IA. THIS HAS HELPED KEEP MIXED LAYER CIN VALUES STILL FAIRLY HIGH WITH IT WEAKENING IN CNTRL IA TOWARD NEBR CITY PER SPC MESO PAGE. THUS...WOULD EXPECT FIRST OR AT LEAST HIGHEST CONVECTION CHANCES WOULD BE IN IA COUNTIES THROUGH SUNSET WHICH WAS SUPPORTED BY EARLIER THAN 18Z RAP AND ALSO 12Z 4KM WRF. WITH DECENT...ALTHOUGH NOT EXCEPTIONALLY HIGH...DEEP SHEAR AND ML CAPE VALUES OF AROUND 2K J/KG....CONDITIONAL SEVERE THREAT REMAINS IN PLACE WITH LARGE HAIL/WIND RISK EARLY PROBABLY SHIFTING MORE TOWARD WIND THREAT THIS EVENING. CONVECTIVE DEVELOPMENT FARTHER SW THIS EVENING OR NORTH OF BOUNDARY OVERNIGHT SOMEWHAT LESS CERTAIN WITH SOME HINTS BY TWO ABOVE SHORTER TERM MODELS INDICATING A LULL LATER THIS EVENING/EARLY TONIGHT BEFORE REDEVELOPMENT TOWARD OR NORTH OF OMAHA/LINCOLN BY 12Z. NE NEBR COULD REMAIN DRY ALL NIGHT...AND EVEN INTO MID/LATE SUN MORNING PER NAM...BUT INTRODUCED MODEST POPS TOWARD 12Z INCREASING INTO CATEGORICAL MOST/ALL AREAS THEN TOWARD MIDDAY. NAM HAD BACKED OFF SOMEWHAT ON COOLING AIRMASS AS PRECIP FELL NRN ZONES...EXCEPT FAR NW...AND 12Z GFS/NAM/ECMWF SUGGESTED THAT MUCH OF THE PRECIP COULD REMAIN LIQUID MUCH OF THE DAY. HOWEVER...KEPT A R/S MIX IN ACROSS NERN NEBR. SOME CONVECTIVE THREAT COULD CONTINUE SERN ZONES INTO AT LEAST MIDDAY AS H85 BOUNDARY REMAINS NEAR SERN NEBR AND WOULD SUSPECT BEST SIGNIFICANT PRECIP CHANCES WOULD FOCUS TOWARD THAT AREA DUE TO LOW/MID LVL FRONTOGENETICAL FORCING. HOWEVER...SOME HINT AT A MID LVL FRONTO BAND OF PRECIP SETTING UP ACROSS THE NORTH THUS AS MENTIONED ABOVE CATEGORICAL POPS WERE MAINTAINED/INCLUDED ALL AREAS AT LEAST SOME POINT IN THE DAY. MOST TEMPS STEADY/FALLING BUT IF PRECIP WOULD STAY OUT OF SERN ZONES UNTIL CLOSER TO MIDDAY COULD SEE A FUTURE NEED FOR A SLIGHT UPWARD BUMP THERE. WINDS OVER N AND W WILL BE STRONG ENOUGH TO POSSIBLY WARRANT AN ADVISORY IN LATER FORECASTS...BUT WILL WAIT UNTIL CONVECTIVE THREAT/PRECIP TRENDS BEFORE THAT PASS FIRST. KEPT RAIN/SNOW MIX W/SNOW ON NW FRINGE MENTION IN FORECAST SUN NIGHT AS COLDER AIR SPILLS SOUTH...ALTHOUGH NOT A CERTAINTY AS GFS ENDS BULK OF PRECIP MOST AREAS AS SOUNDINGS BECOME COLD ENOUGH TO SUPPORT SNOW. WITH SOME WIND/CLOUDS PERSISTING...KEPT LOWS ON OR ABOVE WARMER GUID VALUES SUN NIGHT. WITH SHORTWAVE ENERGY HOLDING BACK INTO MONDAY...DID UP POPS A LITTLE SERN ZONES SUNDAY NIGHT BUT KEPT MONDAY DRY FOR NOW. TEMPS LOOK TO BE WELL BELOW NORMAL. FORECAST LOOKS DRY THEN INTO TUE AND WITH INCREASED MIXING ON TUESDAY AHEAD OF NEXT TROUGH...TEMPERATURES SHOULD RETURN CLOSER TO NORMAL. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 300 PM CDT SAT APR 12 2014 KEPT SLGT CHANCE POPS IN WED AFTN FAR NRN ZONES AS 12Z GFS/ECM BROUGHT NEXT FRONT/TROUGH INTO THAT REGION LATE IN THE DAY. READINGS SHOULD REBOUND AHEAD OF THIS FRONT...AND IF TRENDS PERSIST...COULD SEE A NEED FOR FURTHER RAISING IN LATER FORECASTS. UNCERTAINTIES INCREASE IN THU/FRI PERIOD AS GFS CLOSES OF A COLD UPPER TROUGH LOOKING DOWNRIGHT NASTY THU NIGHT NERN NEBR. WHILE ECMWF WAS MORE PROGRESSIVE...IT TOO TRENDED COLDER. THUS WOULD THINK SOME RAIN/SNOW MIX MENTION WAS STILL WARRANTED WED NGT AND THURSDAY NIGHT NWRN ZONES AND EVEN EXTENDED MENTION INTO THU MORNING. COULD FORESEE THIS THREAT BEING SHIFTED SE IF COLD TRENDS WOULD CONTINUE. SATURDAY DOES APPEAR A RETURN TO NEAR OR ABOVE NORMAL TEMPERATURES...AND POPS WERE MENTIONED PER MODEL BLEND. HOWEVER...MODEL INCONSISTENCY IN THURSDAY AND BEYOND PERIODS LEAD TO LITTLE CONFIDENCE IN MUCH OF THE EXTENDED. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1156 PM CDT SAT APR 12 2014 SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE 10Z TO 14Z TIME FRAME NEAR KLNK AND KOMA...WITH RAIN SPREADING NORTH TO KOFK BY 15Z OR SO. MVFR CIGS/VSBYS CAN BE EXPECTED WITH ANY RAIN/THUNDER INITIALLY...THEN MVFR CIGS WILL ENVELOP ALL OF EASTERN NEBRASKA AS RAIN CONTINUE THROUGH THE AFTERNOON. EXPECT CIGS NEAR FL015 AND VSBYS 3-5SM WITH OCCASIONAL LOWERING OF BOTH CIGS AND VSBYS WITH HEAVIER RAIN MOVES THROUGH. NORTH WINDS WILL ALSO INCREASE INTO THE 15 TO 30KT RANGE BY 15Z AT ALL TAF SITES AND COULD GUST OVER 40KT AT TIMES ESPECIALLY AT KLNK. AS THE PRECIPITATION MOVES OUT OF THE AREA BETWEEN 00Z AND 06Z...EXPECT IMPROVING CONDITIONS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DERGAN SHORT TERM...CHERMOK LONG TERM...CHERMOK AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
806 PM EDT MON APR 14 2014 .SYNOPSIS... VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY... FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY LATE THIS WEEK. && .NEAR TERM /UNTIL 2 AM TUESDAY MORNING/... WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT. && .SHORT TERM /2 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... A LINE OF HEAVY RAIN SHOWERS ARE SLOWLY PUSHING EAST THIS EVENING ACROSS CENTRAL NEW YORK. THESE SHOWERS WILL HAVE VFR CIGS AND IFR VISBYS. CIGS ARE EXPECTED TO FALL TO LOW END MVFR OVER THE NEXT FEW HOURS BEHIND THE LINE OF SHOWERS. THE FORECAST AFTER THE PASSAGE OF THE LINE OF SHOWERS BECOMES MESSY. ADDITIONAL RAIN SHOWERS WILL DEVELOP TONIGHT AFTER 00Z AHEAD OF AN APPROACHING COLD FRONT. THESE SHOWERS WILL BECOME WIDESPREAD AND CONDITIONS WILL FALL BELOW ALTERNATE MINIMUMS IN VISBYS AD CIGS TOWARDS 12Z TUESDAY. THE COLD FRONT WILL BE VERY STRONG AND PRODUCE LLWS FOR A COUPLE OF HOURS AS IT PASSES THROUGH. RAPID COOLING WILL OCCUR BEHIND THE FROPA RESULTING IN A CHANGE OVER TO A WINTRY MIX THEN TO SNOW. EXPECT IFR CONDITIONS FROM 12Z TO 00Z TOMORROW. CONFIDENCE IS MEDIUM TO LOW ON HOW LONG THE LOW CIGS WILL REMAIN LOCKED OVER THE REGION. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NYZ009-037. && $$ SYNOPSIS...MSE NEAR TERM...BMW SHORT TERM...MSE LONG TERM... AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
639 PM EDT SUN APR 13 2014 .SYNOPSIS... LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT...WITH THE POTENTIAL FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY. && .NEAR TERM /THROUGH MONDAY/... 635 PM UPDATE... REMOVED SLIGHT CHANCE OF SHOWER FROM ONEIDA COUNTY THIS EVENING WITH BOUNDARY LAYER BEING TOO DRY TO REALIZE THE SPOTTY QPF OF EARLIER MODELS. WITH A GOOD AMOUNT OF SUNSHINE SINCE THE HIGH THIN CLOUDS ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A FEW DEGREES SHY OF DAILY RECORDS. PREVIOUS DISCUSSION... VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD MINS TNGT. NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT -SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT. TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE FNT ON TUE. BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF CNTRL NY. MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH COOLER WITH MAXES ONLY U30S TO L40S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH 18Z MONDAY. THROUGH EARLY EVENING SCT/BKN MID/HIGH LEVEL CLOUDS. AT KRME/KSYR, A NON RESTRICTIVE LIGHT SHOWER IN POSSIBLE DUE TO PROXIMITY TO WARM FRONT BUT NOT INCLUDED IN TAF DUE TO LOW PROBABILITY. OVERNIGHT AND THROUGH EARLY AFTERNOON MONDAY JUST HIGH CLOUDS WELL IN ADVANCE OF SFC TROF. DURING THE LATE AFTERNOON PERIOD SCATTERED CONVECTION IS POSSIBLE WITH BRIEF RESTRICTIONS. SOUTHWEST WINDS AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS DECREASING THIS EVENING TO AROUND 10 KNOTS. SOUTHWEST WINDS INCREASING AGAIN BY MID MORNING AT 15-20 KNOTS WITH GUSTS NEAR 3O KNOTS. OUTLOOK... MON NIGHT/TUE...MVFR/IFR RESTRICTIONS IN RAIN SHOWERS CHANGING TO SNOW SHOWERS DURING THE AFTERNOON PERIOD. TUESDAY NIGHT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED...VFR. THURSDAY/FRIDAY...VFR. && .FIRE WEATHER... 635 PM SUNDAY UPDATE... CONDITIONS APPROACHED CRITICAL VALUES THIS AFTERNOON /SUNDAY/ BUT WINDS WILL CONTINUE TO BACK OFF THIS EVENING ALONG WITH GRADUALLY RECOVERING RELATIVE HUMIDITY. FAIRLY WARM WITH STOUT SOUTH- SOUTHWEST WINDS AGAIN MONDAY...BUT WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS WHAT WE JUST HAD THIS SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25 PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON- EVENING /ESPECIALLY CENTRAL NY/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...MDP SHORT TERM... LONG TERM...RRM AVIATION...RRM FIRE WEATHER...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
153 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM SOUTHWEST FLOW WILL PERSIST OVER THE AREA THROUGH MONDAY WITH HIGH TEMPERATURES REACHING INTO THE 70S TODAY AND MONDAY. A COLD FRONT WILL PASS THROUGH THE AREA ON TUESDAY PROVIDING A SOAKING RAIN. OVERNIGHT TEMPERATURES BEHIND THE COLD FRONT ON TUESDAY NIGHT WILL DROP DOWN INTO THE 20S. && .NEAR TERM /THROUGH TONIGHT/... 1020 AM UPDATE...HAVE INTRODUCED LOW CHC POPS FOR NRN ZONES LATE THIS AFTN AND EARLY EVNG FOR POTNL -SHRA AS NXT WEAK S/WV GOES BY. ACTIVITY MAY BE AIDED BY LOW LVL CONVERGENCE ASSCD WITH FNTL BNDRY. OTRW HI CLD DECK HAS THINNED OVER THE PAST FEW HRS ALLOWING FOR MORE SUNSHINE. HAVE RAISED TEMPS BY A FEW DEG WITH MAXES ARND 80 CNTRL SRN TIER INTO THE FINGER LAKES. PREV BLO... 825 AM UPDATE...WE HAVE LOWERED POPS ACRS NRN ZONES AS MOST OF THE -SHRA ACTIVITY HAS MOVD OUT OF THE RGN. LOTS OF UPR CLD ACRS THE AREA TDA. RUC ADVERTISES 925 TEMPS OF 20-22C IN AN AXIS ACRS THE CNTRL SRN TIER AND FINGER LAKES...WHICH IF MIXED DOWN WITH FULL SUN WOULD RESULT IN MAXES OF 80-85. THESE 925 FCST TEMPS ARE A FEW DEG WARMER THAN OTHER GUIDANCE (WE NOTE +17C AT 925 FROM THE 12Z BUF SNDG). GIVEN THIS AND THE ABUNDANT CLD HI CLD CVR WE`LL LEAVE MAXES AS IS. PREV BLO... 5 AM UPDATE... MINOR UPDATE TO ADD IN SPRINKLES AND/OR ISOLD SHOWERS ACRS NEPA AND WRN CATS FORMING ON NOSE OF H8 LLJ. HV RMVD THUNDER MENTION FOR THIS MRNG FM ALL GRIDS AS NO LGTNG STRIKES NOTED IN THE LAST 4 HRS. ALL ELSE LOOKS TO BE ON TRACK AT THIS TIME WITH BULK OF THE PCPN LKLY TO BE NORTH OF CWA WITHIN THE NEXT COUPLE OF HRS. PREV DISCUSSION BLO... 330 AM UPDATE... WMFNT WL LIFT THRU CWA THIS MRNG, LVG AREA IN WARM SECTOR AND SWRLY FLOW. LGT RAIN SHOWERS EXPECTED ACRS NRN ZONES THIS MRNG WL LIFT NORTH AS BNDRY LIFTS THRU THE REGION. CLDS WL GRADUALLY BE ON THE DECREASE BUT WITH AREA IN INCRSG MID-LVL MOISTURE RIDING NORTH EXPECT CUMULUS TO DVLP AND RESULT IN PCLDY CONDS THROUGHOUT THE DAY. H8 TEMPS CLIMBING TO +12C EXPECTED TO YIELD ANOTHER SUMMERY DAY. HIGH TEMPS WL BE SVRL DEGREES WARMER THAN YDA WITH L/M 70S COMMON ACRS THE AREA - NEARLY 15-20 DEGREES ABV NORMAL. WARM SW FLOW WL CONTINUE TONIGHT AS CWA RMNS LOCKED INTO WM SECTOR. BY 12Z MONDAY EXPECT CDFNT TO BE LOCATED IN VICINITY OF THE THUMB OF LWR MICHIGAN AND SLIDING EAST. GOM WL BE WIDE OPEN TONIGHT WITH H8 WINDS DRAWING IN PW VALUES APPCHG 1 INCH BY 12Z MONDAY. THIS IS ALREADY 1-2 SD ABV NORMAL FOR THIS TIME OF YR. DWPT VALUES WL INCREASE INTO THE 50S TONIGHT WITH OVRNGT LOWS ONLY DROPPING INTO THE MID-50S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... 330 AM UPDATE... FRONT WL APPCH EVER CLOSER DRG THE DAY MONDAY, BUT STILL RMN FAR ENUF TO THE WEST THAT PCPN WL BE HARD-PRESSED TO MV INTO CWA MUCH BFR 21Z. IT IS POSSIBLE THAT AN ISOLD SHOWER OR TWO WL OCCUR AFT 18Z AS LEAD S/WV TRACKS THRU THE AREA BUT BEST FRCG LOOKS TO BE ALONG FRONT TWD 00Z. HV BACKED OFF SLIGHTLY WITH POPS FOR MON AFTN TO ACCNT FOR SLOWER MVMNT OF CDFNT PER 00Z NAM AND EC. INSTABILITY IS PROGGED TO INCRS ON MONDAY WITH SHOWERS EXPECTED EARLY THAN GIVING WAY TO ISOLD CONVECTION BY LATE AFTN. GIVEN INCRSG MOISTURE ALONG WITH CLDS HV DROPPED MAX TEMPS BY A DEGREE OR TWO BUT STILL RANGING IN THE LWR TO UPR 70S. AN 80-DEGREE READING IS NOT OUT OF THE QUESTION. FROPA EXPECTED TO HOLD OFF UNTIL SOMETIME TUE MRNG, THUS HV BUMPED TEMPS AND DWPT VALUES UP FOR MON NGT. EXPECT MOST OF THE AREA TO BE LOCKED INTO SHOWERS WITH SOME THUNDER AFTER 06Z. MED RANGE MODELS GIVING SOME INDICATION OF LIGHTER PCPN OCCURRING IN SHADOWING AFFECTS IN SRLY FLOW ACRS CNTR SXN OF CWA TWD 12Z. THUS, EXPECT HIGHER QPF AMNTS BTWN 06Z AND 12Z TUE ACRS NW ZONES AND TERRAIN AREAS OF SERN ZONES. FROPA NOW EXPECTED TO HAPPEN DRG THE DAY ON TUE WITH RAINY DAY EXPECTED. HEAVIEST PCPN LOOKS TO FALL DRG THE MAIN PART OF THE DAY WITH STORM-TOTAL QPF AMNTS BTWN 12Z TUE-00Z WED ARND 1 INCH. THIS WL BE IN CONJUNCTION WITH RRQ OF 250MB JET STREAK LEADING TO STRONG FRCG OVR MOST OF CWA DRG THE DAY. TEMPS EXPECTED TO FALL DRG THE COURSE OF THE DAY WITH HIGH TEMPS OCCURRING AT DAYBREAK ACRS NRN ZONES, MID-MRNG OVR CNTRL SXNS AND EARLY AFTN ACRS NEPA. HV SIDED WITH NON-DIURNAL TREND OF MET/MAV GUIDANCE AS THEY SEEM TO BE MOST REASONABLE. 00Z EURO LOOKS WAY TOO COLD FOR TEMPS ON TUE WITH TEMPS DOWN INTO THE 20S AREAWIDE BY 00Z WED. TUE NGT EXPECTED TO BE VRY CLD WITH LOWS ULTIMATELY DROPPING INTO THE 20S AND POSSIBLY TEENS OVR NRN ONEIDA CNTY. ANY LINGERING PCPN WL MIX WITH AND EVENTUALLY CHG TO SNOW DRG THE OVRNGT WITH ONLY A DUSTING EXPECTED OVR HIGHER TERRAIN OF WRN CATS. SFC HIPRES QUICKLY BUILDS IN AFT 06Z. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH 18Z MONDAY. THROUGH EARLY EVENING SCT/BKN MID/HIGH LEVEL CLOUDS. AT KRME/KSYR, A NON RESTRICTIVE LIGHT SHOWER IN POSSIBLE DUE TO PROXIMITY TO WARM FRONT BUT NOT INCLUDED IN TAF DUE TO LOW PROBABILITY. OVERNIGHT AND THROUGH EARLY AFTERNOON MONDAY JUST HIGH CLOUDS WELL IN ADVANCE OF SFC TROF. DURING THE LATE AFTERNOON PERIOD SCATTERED CONVECTION IS POSSIBLE WITH BRIEF RESTRICTIONS. SOUTHWEST WINDS AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS DECREASING THIS EVENING TO AROUND 10 KNOTS. SOUTHWEST WINDS INCREASING AGAIN BY MID MORNING AT 15-20 KNOTS WITH GUSTS NEAR 3O KNOTS. OUTLOOK... MON NIGHT/TUE...MVFR/IFR RESTRICTIONS IN RAIN SHOWERS CHANGING TO SNOW SHOWERS DURING THE AFTERNOON PERIOD. TUESDAY NIGHT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED...VFR. THURSDAY/FRIDAY...VFR. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS MOISTURE INCREASES AHEAD OF NEXT STORM SYSTEM TODAY THROUGH TUESDAY. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...RRM AVIATION...RRM FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
150 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM SOUTHWEST FLOW WILL PERSIST OVER THE AREA THROUGH MONDAY WITH HIGH TEMPERATURES REACHING INTO THE 70S TODAY AND MONDAY. A COLD FRONT WILL PASS THROUGH THE AREA ON TUESDAY PROVIDING A SOAKING RAIN. OVERNIGHT TEMPERATURES BEHIND THE COLD FRONT ON TUESDAY NIGHT WILL DROP DOWN INTO THE 20S. && .NEAR TERM /THROUGH TONIGHT/... 1020 AM UPDATE...HAVE INTRODUCED LOW CHC POPS FOR NRN ZONES LATE THIS AFTN AND EARLY EVNG FOR POTNL -SHRA AS NXT WEAK S/WV GOES BY. ACTIVITY MAY BE AIDED BY LOW LVL CONVERGENCE ASSCD WITH FNTL BNDRY. OTRW HI CLD DECK HAS THINNED OVER THE PAST FEW HRS ALLOWING FOR MORE SUNSHINE. HAVE RAISED TEMPS BY A FEW DEG WITH MAXES ARND 80 CNTRL SRN TIER INTO THE FINGER LAKES. PREV BLO... 825 AM UPDATE...WE HAVE LOWERED POPS ACRS NRN ZONES AS MOST OF THE -SHRA ACTIVITY HAS MOVD OUT OF THE RGN. LOTS OF UPR CLD ACRS THE AREA TDA. RUC ADVERTISES 925 TEMPS OF 20-22C IN AN AXIS ACRS THE CNTRL SRN TIER AND FINGER LAKES...WHICH IF MIXED DOWN WITH FULL SUN WOULD RESULT IN MAXES OF 80-85. THESE 925 FCST TEMPS ARE A FEW DEG WARMER THAN OTHER GUIDANCE (WE NOTE +17C AT 925 FROM THE 12Z BUF SNDG). GIVEN THIS AND THE ABUNDANT CLD HI CLD CVR WE`LL LEAVE MAXES AS IS. PREV BLO... 5 AM UPDATE... MINOR UPDATE TO ADD IN SPRINKLES AND/OR ISOLD SHOWERS ACRS NEPA AND WRN CATS FORMING ON NOSE OF H8 LLJ. HV RMVD THUNDER MENTION FOR THIS MRNG FM ALL GRIDS AS NO LGTNG STRIKES NOTED IN THE LAST 4 HRS. ALL ELSE LOOKS TO BE ON TRACK AT THIS TIME WITH BULK OF THE PCPN LKLY TO BE NORTH OF CWA WITHIN THE NEXT COUPLE OF HRS. PREV DISCUSSION BLO... 330 AM UPDATE... WMFNT WL LIFT THRU CWA THIS MRNG, LVG AREA IN WARM SECTOR AND SWRLY FLOW. LGT RAIN SHOWERS EXPECTED ACRS NRN ZONES THIS MRNG WL LIFT NORTH AS BNDRY LIFTS THRU THE REGION. CLDS WL GRADUALLY BE ON THE DECREASE BUT WITH AREA IN INCRSG MID-LVL MOISTURE RIDING NORTH EXPECT CUMULUS TO DVLP AND RESULT IN PCLDY CONDS THROUGHOUT THE DAY. H8 TEMPS CLIMBING TO +12C EXPECTED TO YIELD ANOTHER SUMMERY DAY. HIGH TEMPS WL BE SVRL DEGREES WARMER THAN YDA WITH L/M 70S COMMON ACRS THE AREA - NEARLY 15-20 DEGREES ABV NORMAL. WARM SW FLOW WL CONTINUE TONIGHT AS CWA RMNS LOCKED INTO WM SECTOR. BY 12Z MONDAY EXPECT CDFNT TO BE LOCATED IN VICINITY OF THE THUMB OF LWR MICHIGAN AND SLIDING EAST. GOM WL BE WIDE OPEN TONIGHT WITH H8 WINDS DRAWING IN PW VALUES APPCHG 1 INCH BY 12Z MONDAY. THIS IS ALREADY 1-2 SD ABV NORMAL FOR THIS TIME OF YR. DWPT VALUES WL INCREASE INTO THE 50S TONIGHT WITH OVRNGT LOWS ONLY DROPPING INTO THE MID-50S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... 330 AM UPDATE... FRONT WL APPCH EVER CLOSER DRG THE DAY MONDAY, BUT STILL RMN FAR ENUF TO THE WEST THAT PCPN WL BE HARD-PRESSED TO MV INTO CWA MUCH BFR 21Z. IT IS POSSIBLE THAT AN ISOLD SHOWER OR TWO WL OCCUR AFT 18Z AS LEAD S/WV TRACKS THRU THE AREA BUT BEST FRCG LOOKS TO BE ALONG FRONT TWD 00Z. HV BACKED OFF SLIGHTLY WITH POPS FOR MON AFTN TO ACCNT FOR SLOWER MVMNT OF CDFNT PER 00Z NAM AND EC. INSTABILITY IS PROGGED TO INCRS ON MONDAY WITH SHOWERS EXPECTED EARLY THAN GIVING WAY TO ISOLD CONVECTION BY LATE AFTN. GIVEN INCRSG MOISTURE ALONG WITH CLDS HV DROPPED MAX TEMPS BY A DEGREE OR TWO BUT STILL RANGING IN THE LWR TO UPR 70S. AN 80-DEGREE READING IS NOT OUT OF THE QUESTION. FROPA EXPECTED TO HOLD OFF UNTIL SOMETIME TUE MRNG, THUS HV BUMPED TEMPS AND DWPT VALUES UP FOR MON NGT. EXPECT MOST OF THE AREA TO BE LOCKED INTO SHOWERS WITH SOME THUNDER AFTER 06Z. MED RANGE MODELS GIVING SOME INDICATION OF LIGHTER PCPN OCCURRING IN SHADOWING AFFECTS IN SRLY FLOW ACRS CNTR SXN OF CWA TWD 12Z. THUS, EXPECT HIGHER QPF AMNTS BTWN 06Z AND 12Z TUE ACRS NW ZONES AND TERRAIN AREAS OF SERN ZONES. FROPA NOW EXPECTED TO HAPPEN DRG THE DAY ON TUE WITH RAINY DAY EXPECTED. HEAVIEST PCPN LOOKS TO FALL DRG THE MAIN PART OF THE DAY WITH STORM-TOTAL QPF AMNTS BTWN 12Z TUE-00Z WED ARND 1 INCH. THIS WL BE IN CONJUNCTION WITH RRQ OF 250MB JET STREAK LEADING TO STRONG FRCG OVR MOST OF CWA DRG THE DAY. TEMPS EXPECTED TO FALL DRG THE COURSE OF THE DAY WITH HIGH TEMPS OCCURRING AT DAYBREAK ACRS NRN ZONES, MID-MRNG OVR CNTRL SXNS AND EARLY AFTN ACRS NEPA. HV SIDED WITH NON-DIURNAL TREND OF MET/MAV GUIDANCE AS THEY SEEM TO BE MOST REASONABLE. 00Z EURO LOOKS WAY TOO COLD FOR TEMPS ON TUE WITH TEMPS DOWN INTO THE 20S AREAWIDE BY 00Z WED. TUE NGT EXPECTED TO BE VRY CLD WITH LOWS ULTIMATELY DROPPING INTO THE 20S AND POSSIBLY TEENS OVR NRN ONEIDA CNTY. ANY LINGERING PCPN WL MIX WITH AND EVENTUALLY CHG TO SNOW DRG THE OVRNGT WITH ONLY A DUSTING EXPECTED OVR HIGHER TERRAIN OF WRN CATS. SFC HIPRES QUICKLY BUILDS IN AFT 06Z. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH 18Z MONDAY. THROUGH EARLY EVENING SCT/BKN MID/HIGH LEVEL CLOUDS. AT KRME/KSYR, A NON RESTRICTIVE LIGHT SHOWER IN POSSIBLE DUE TO PROXIMITY TO WARM FRONT BUT NOT INCLUDED IN TAF DUE TO LOW PROBABILITY. OVERNIGHT AND THROUGH EARLY AFTERNOON MONDAY JUST HIGH CLOUDS WELL IN ADVANCE OF SFC TROF. DURING THE LATE AFTERNOON PERIOD SCATTERED CONVECTION IS POSSIBLE WITH BRIEF RESTRICTIONS. SOUTHWEST WINDS AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS DECREASING THIS EVENING TO AROUND 10 KNOTS. SOUTHWEST WINDS INCREASING AGAIN BY MID MORNING AT 15-20 KNOTS WITH GUSTS NEAR 3O KNOTS. OUTLOOK... MON NIGHT/TUE...MVFR/IFR RESTRICTIONS IN RAIN SHOWERS CHANGING TO SNOW SHOWERS DURING THE AFTERNOON PERIOD. TUESDAY NIGHT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS. WED...VFR. THURSDAY/FRIDAY...VFR. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS MOISTURE INCREASES AHEAD OF NEXT STORM SYSTEM TODAY THROUGH TUESDAY. .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...RRM AVIATION...CMG/RRM FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1237 PM EDT SUN APR 13 2014 .SYNOPSIS... A WARM SOUTHWEST FLOW WILL PERSIST OVER THE AREA THROUGH MONDAY WITH HIGH TEMPERATURES REACHING INTO THE 70S TODAY AND MONDAY. A COLD FRONT WILL PASS THROUGH THE AREA ON TUESDAY PROVIDING A SOAKING RAIN. OVERNIGHT TEMPERATURES BEHIND THE COLD FRONT ON TUESDAY NIGHT WILL DROP DOWN INTO THE 20S. && .NEAR TERM /THROUGH TONIGHT/... 1020 AM UPDATE...HAVE INTRODUCED LOW CHC POPS FOR NRN ZONES LATE THIS AFTN AND EARLY EVNG FOR POTNL -SHRA AS NXT WEAK S/WV GOES BY. ACTIVITY MAY BE AIDED BY LOW LVL CONVERGENCE ASSCD WITH FNTL BNDRY. OTRW HI CLD DECK HAS THINNED OVER THE PAST FEW HRS ALLOWING FOR MORE SUNSHINE. HAVE RAISED TEMPS BY A FEW DEG WITH MAXES ARND 80 CNTRL SRN TIER INTO THE FINGER LAKES. PREV BLO... 825 AM UPDATE...WE HAVE LOWERED POPS ACRS NRN ZONES AS MOST OF THE -SHRA ACTIVITY HAS MOVD OUT OF THE RGN. LOTS OF UPR CLD ACRS THE AREA TDA. RUC ADVERTISES 925 TEMPS OF 20-22C IN AN AXIS ACRS THE CNTRL SRN TIER AND FINGER LAKES...WHICH IF MIXED DOWN WITH FULL SUN WOULD RESULT IN MAXES OF 80-85. THESE 925 FCST TEMPS ARE A FEW DEG WARMER THAN OTHER GUIDANCE (WE NOTE +17C AT 925 FROM THE 12Z BUF SNDG). GIVEN THIS AND THE ABUNDANT CLD HI CLD CVR WE`LL LEAVE MAXES AS IS. PREV BLO... 5 AM UPDATE... MINOR UPDATE TO ADD IN SPRINKLES AND/OR ISOLD SHOWERS ACRS NEPA AND WRN CATS FORMING ON NOSE OF H8 LLJ. HV RMVD THUNDER MENTION FOR THIS MRNG FM ALL GRIDS AS NO LGTNG STRIKES NOTED IN THE LAST 4 HRS. ALL ELSE LOOKS TO BE ON TRACK AT THIS TIME WITH BULK OF THE PCPN LKLY TO BE NORTH OF CWA WITHIN THE NEXT COUPLE OF HRS. PREV DISCUSSION BLO... 330 AM UPDATE... WMFNT WL LIFT THRU CWA THIS MRNG, LVG AREA IN WARM SECTOR AND SWRLY FLOW. LGT RAIN SHOWERS EXPECTED ACRS NRN ZONES THIS MRNG WL LIFT NORTH AS BNDRY LIFTS THRU THE REGION. CLDS WL GRADUALLY BE ON THE DECREASE BUT WITH AREA IN INCRSG MID-LVL MOISTURE RIDING NORTH EXPECT CUMULUS TO DVLP AND RESULT IN PCLDY CONDS THROUGHOUT THE DAY. H8 TEMPS CLIMBING TO +12C EXPECTED TO YIELD ANOTHER SUMMERY DAY. HIGH TEMPS WL BE SVRL DEGREES WARMER THAN YDA WITH L/M 70S COMMON ACRS THE AREA - NEARLY 15-20 DEGREES ABV NORMAL. WARM SW FLOW WL CONTINUE TONIGHT AS CWA RMNS LOCKED INTO WM SECTOR. BY 12Z MONDAY EXPECT CDFNT TO BE LOCATED IN VICINITY OF THE THUMB OF LWR MICHIGAN AND SLIDING EAST. GOM WL BE WIDE OPEN TONIGHT WITH H8 WINDS DRAWING IN PW VALUES APPCHG 1 INCH BY 12Z MONDAY. THIS IS ALREADY 1-2 SD ABV NORMAL FOR THIS TIME OF YR. DWPT VALUES WL INCREASE INTO THE 50S TONIGHT WITH OVRNGT LOWS ONLY DROPPING INTO THE MID-50S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... 330 AM UPDATE... FRONT WL APPCH EVER CLOSER DRG THE DAY MONDAY, BUT STILL RMN FAR ENUF TO THE WEST THAT PCPN WL BE HARD-PRESSED TO MV INTO CWA MUCH BFR 21Z. IT IS POSSIBLE THAT AN ISOLD SHOWER OR TWO WL OCCUR AFT 18Z AS LEAD S/WV TRACKS THRU THE AREA BUT BEST FRCG LOOKS TO BE ALONG FRONT TWD 00Z. HV BACKED OFF SLIGHTLY WITH POPS FOR MON AFTN TO ACCNT FOR SLOWER MVMNT OF CDFNT PER 00Z NAM AND EC. INSTABILITY IS PROGGED TO INCRS ON MONDAY WITH SHOWERS EXPECTED EARLY THAN GIVING WAY TO ISOLD CONVECTION BY LATE AFTN. GIVEN INCRSG MOISTURE ALONG WITH CLDS HV DROPPED MAX TEMPS BY A DEGREE OR TWO BUT STILL RANGING IN THE LWR TO UPR 70S. AN 80-DEGREE READING IS NOT OUT OF THE QUESTION. FROPA EXPECTED TO HOLD OFF UNTIL SOMETIME TUE MRNG, THUS HV BUMPED TEMPS AND DWPT VALUES UP FOR MON NGT. EXPECT MOST OF THE AREA TO BE LOCKED INTO SHOWERS WITH SOME THUNDER AFTER 06Z. MED RANGE MODELS GIVING SOME INDICATION OF LIGHTER PCPN OCCURRING IN SHADOWING AFFECTS IN SRLY FLOW ACRS CNTR SXN OF CWA TWD 12Z. THUS, EXPECT HIGHER QPF AMNTS BTWN 06Z AND 12Z TUE ACRS NW ZONES AND TERRAIN AREAS OF SERN ZONES. FROPA NOW EXPECTED TO HAPPEN DRG THE DAY ON TUE WITH RAINY DAY EXPECTED. HEAVIEST PCPN LOOKS TO FALL DRG THE MAIN PART OF THE DAY WITH STORM-TOTAL QPF AMNTS BTWN 12Z TUE-00Z WED ARND 1 INCH. THIS WL BE IN CONJUNCTION WITH RRQ OF 250MB JET STREAK LEADING TO STRONG FRCG OVR MOST OF CWA DRG THE DAY. TEMPS EXPECTED TO FALL DRG THE COURSE OF THE DAY WITH HIGH TEMPS OCCURRING AT DAYBREAK ACRS NRN ZONES, MID-MRNG OVR CNTRL SXNS AND EARLY AFTN ACRS NEPA. HV SIDED WITH NON-DIURNAL TREND OF MET/MAV GUIDANCE AS THEY SEEM TO BE MOST REASONABLE. 00Z EURO LOOKS WAY TOO COLD FOR TEMPS ON TUE WITH TEMPS DOWN INTO THE 20S AREAWIDE BY 00Z WED. TUE NGT EXPECTED TO BE VRY CLD WITH LOWS ULTIMATELY DROPPING INTO THE 20S AND POSSIBLY TEENS OVR NRN ONEIDA CNTY. ANY LINGERING PCPN WL MIX WITH AND EVENTUALLY CHG TO SNOW DRG THE OVRNGT WITH ONLY A DUSTING EXPECTED OVR HIGHER TERRAIN OF WRN CATS. SFC HIPRES QUICKLY BUILDS IN AFT 06Z. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VFR CONDITIONS EXPECTED THROUGH THE FCST CYCLE. LGT RAIN SHWRS EARLY ON IN THE VICINITY OF SYR AND RME WILL QUICKLY RETREAT AS A WARM FRONT LIFTS NORTH INTO NORTHERN NY. AS THE HEATING CYCLE BEGINS...WINDS WILL INCREASE FROM THE SOUTHWEST WITH GUSTS UP TO 25 KTS LIKELY UNDER STRONG BOUNDARY LAYER MIXING. WINDS WILL BEGIN TO WEAKEN BY EARLY EVENING WITH ONLY UPPER CI EXPECTED AFTER 04Z. OUTLOOK... MON...VFR. MON NIGHT/TUE/TUE NGT...MVFR/IFR RESTRICTIONS IN SHOWERS. WED...VFR. THURS...VFR. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS MOISTURE INCREASES AHEAD OF NEXT STORM SYSTEM TODAY THROUGH TUESDAY. .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...RRM AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1021 AM EDT SUN APR 13 2014 .SYNOPSIS... A WARM SOUTHWEST FLOW WILL PERSIST OVER THE AREA THROUGH MONDAY WITH HIGH TEMPERATURES REACHING INTO THE 70S TODAY AND MONDAY. A COLD FRONT WILL PASS THROUGH THE AREA ON TUESDAY PROVIDING A SOAKING RAIN. OVERNIGHT TEMPERATURES BEHIND THE COLD FRONT ON TUESDAY NIGHT WILL DROP DOWN INTO THE 20S. && .NEAR TERM /THROUGH TONIGHT/... 1020 AM UPDATE...HAVE INTRODUCED LOW CHC POPS FOR NRN ZONES LATE THIS AFTN AND EARLY EVNG FOR POTNL -SHRA AS NXT WEAK S/WV GOES BY. ACTIVITY MAY BE AIDED BY LOW LVL CONVERGENCE ASSCD WITH FNTL BNDRY. OTRW HI CLD DECK HAS THINNED OVER THE PAST FEW HRS ALLOWING FOR MORE SUNSHINE. HAVE RAISED TEMPS BY A FEW DEG WITH MAXES ARND 80 CNTRL SRN TIER INTO THE FINGER LAKES. PREV BLO... 825 AM UPDATE...WE HAVE LOWERED POPS ACRS NRN ZONES AS MOST OF THE -SHRA ACTIVITY HAS MOVD OUT OF THE RGN. LOTS OF UPR CLD ACRS THE AREA TDA. RUC ADVERTISES 925 TEMPS OF 20-22C IN AN AXIS ACRS THE CNTRL SRN TIER AND FINGER LAKES...WHICH IF MIXED DOWN WITH FULL SUN WOULD RESULT IN MAXES OF 80-85. THESE 925 FCST TEMPS ARE A FEW DEG WARMER THAN OTHER GUIDANCE (WE NOTE +17C AT 925 FROM THE 12Z BUF SNDG). GIVEN THIS AND THE ABUNDANT CLD HI CLD CVR WE`LL LEAVE MAXES AS IS. PREV BLO... 5 AM UPDATE... MINOR UPDATE TO ADD IN SPRINKLES AND/OR ISOLD SHOWERS ACRS NEPA AND WRN CATS FORMING ON NOSE OF H8 LLJ. HV RMVD THUNDER MENTION FOR THIS MRNG FM ALL GRIDS AS NO LGTNG STRIKES NOTED IN THE LAST 4 HRS. ALL ELSE LOOKS TO BE ON TRACK AT THIS TIME WITH BULK OF THE PCPN LKLY TO BE NORTH OF CWA WITHIN THE NEXT COUPLE OF HRS. PREV DISCUSSION BLO... 330 AM UPDATE... WMFNT WL LIFT THRU CWA THIS MRNG, LVG AREA IN WARM SECTOR AND SWRLY FLOW. LGT RAIN SHOWERS EXPECTED ACRS NRN ZONES THIS MRNG WL LIFT NORTH AS BNDRY LIFTS THRU THE REGION. CLDS WL GRADUALLY BE ON THE DECREASE BUT WITH AREA IN INCRSG MID-LVL MOISTURE RIDING NORTH EXPECT CUMULUS TO DVLP AND RESULT IN PCLDY CONDS THROUGHOUT THE DAY. H8 TEMPS CLIMBING TO +12C EXPECTED TO YIELD ANOTHER SUMMERY DAY. HIGH TEMPS WL BE SVRL DEGREES WARMER THAN YDA WITH L/M 70S COMMON ACRS THE AREA - NEARLY 15-20 DEGREES ABV NORMAL. WARM SW FLOW WL CONTINUE TONIGHT AS CWA RMNS LOCKED INTO WM SECTOR. BY 12Z MONDAY EXPECT CDFNT TO BE LOCATED IN VICINITY OF THE THUMB OF LWR MICHIGAN AND SLIDING EAST. GOM WL BE WIDE OPEN TONIGHT WITH H8 WINDS DRAWING IN PW VALUES APPCHG 1 INCH BY 12Z MONDAY. THIS IS ALREADY 1-2 SD ABV NORMAL FOR THIS TIME OF YR. DWPT VALUES WL INCREASE INTO THE 50S TONIGHT WITH OVRNGT LOWS ONLY DROPPING INTO THE MID-50S. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... 330 AM UPDATE... FRONT WL APPCH EVER CLOSER DRG THE DAY MONDAY, BUT STILL RMN FAR ENUF TO THE WEST THAT PCPN WL BE HARD-PRESSED TO MV INTO CWA MUCH BFR 21Z. IT IS POSSIBLE THAT AN ISOLD SHOWER OR TWO WL OCCUR AFT 18Z AS LEAD S/WV TRACKS THRU THE AREA BUT BEST FRCG LOOKS TO BE ALONG FRONT TWD 00Z. HV BACKED OFF SLIGHTLY WITH POPS FOR MON AFTN TO ACCNT FOR SLOWER MVMNT OF CDFNT PER 00Z NAM AND EC. INSTABILITY IS PROGGED TO INCRS ON MONDAY WITH SHOWERS EXPECTED EARLY THAN GIVING WAY TO ISOLD CONVECTION BY LATE AFTN. GIVEN INCRSG MOISTURE ALONG WITH CLDS HV DROPPED MAX TEMPS BY A DEGREE OR TWO BUT STILL RANGING IN THE LWR TO UPR 70S. AN 80-DEGREE READING IS NOT OUT OF THE QUESTION. FROPA EXPECTED TO HOLD OFF UNTIL SOMETIME TUE MRNG, THUS HV BUMPED TEMPS AND DWPT VALUES UP FOR MON NGT. EXPECT MOST OF THE AREA TO BE LOCKED INTO SHOWERS WITH SOME THUNDER AFTER 06Z. MED RANGE MODELS GIVING SOME INDICATION OF LIGHTER PCPN OCCURRING IN SHADOWING AFFECTS IN SRLY FLOW ACRS CNTR SXN OF CWA TWD 12Z. THUS, EXPECT HIGHER QPF AMNTS BTWN 06Z AND 12Z TUE ACRS NW ZONES AND TERRAIN AREAS OF SERN ZONES. FROPA NOW EXPECTED TO HAPPEN DRG THE DAY ON TUE WITH RAINY DAY EXPECTED. HEAVIEST PCPN LOOKS TO FALL DRG THE MAIN PART OF THE DAY WITH STORM-TOTAL QPF AMNTS BTWN 12Z TUE-00Z WED ARND 1 INCH. THIS WL BE IN CONJUNCTION WITH RRQ OF 250MB JET STREAK LEADING TO STRONG FRCG OVR MOST OF CWA DRG THE DAY. TEMPS EXPECTED TO FALL DRG THE COURSE OF THE DAY WITH HIGH TEMPS OCCURRING AT DAYBREAK ACRS NRN ZONES, MID-MRNG OVR CNTRL SXNS AND EARLY AFTN ACRS NEPA. HV SIDED WITH NON-DIURNAL TREND OF MET/MAV GUIDANCE AS THEY SEEM TO BE MOST REASONABLE. 00Z EURO LOOKS WAY TOO COLD FOR TEMPS ON TUE WITH TEMPS DOWN INTO THE 20S AREAWIDE BY 00Z WED. TUE NGT EXPECTED TO BE VRY CLD WITH LOWS ULTIMATELY DROPPING INTO THE 20S AND POSSIBLY TEENS OVR NRN ONEIDA CNTY. ANY LINGERING PCPN WL MIX WITH AND EVENTUALLY CHG TO SNOW DRG THE OVRNGT WITH ONLY A DUSTING EXPECTED OVR HIGHER TERRAIN OF WRN CATS. SFC HIPRES QUICKLY BUILDS IN AFT 06Z. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... QUIET BUT BELOW NORMAL PERIOD SETTING UP EARLY ON AS CANADIAN HIGH PRESSURE SETTLES OVER THE REGION FOLLOWING TUESDAY/S COLD FRONT. HIGH TEMPS LOOK TO ONLY WARM INTO THE LOWER THE MIDDLE 40S ON WEDNESDAY...WITH SLIGHT MODERATION EXPECTED THROUGH THE DURATION OF THE WORK WEEK. NEXT CHANCE FOR PRECIP LOOKS TO ARRIVE NEXT WEEKEND AS SERIES OF TROUGHS CONSOLIDATE OVER THE NATION/S MIDSECTION. AS THIS OCCURS...BOTH THE GFS AND ECMWF SHOW DEVELOPING CYCLOGENESIS ACROSS THE MID MISS RVR VLY WITH THIS LOW GRADUALLY LIFTING NORTH WELL WEST OF OUR FCST AREA. THAT SAID...THE GFS SHOWS A MUCH MORE AMPLIFIED WOUND-UP CLOSED LOW SOLUTION WHILE THE ECMWF MAINTAINS A PROGRESSIVE OPEN WAVE. AS ONE CAN IMAGINE THE FORMER OFFERS A WETTER SOLUTION THAN THE LATTER. BASED ON THESE DIFFERENCES AND DISTANCE OUT INTO THE FCST PERIOD...NO SIGNIFICANT CHANGES MADE THIS MORNING. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... VFR CONDITIONS EXPECTED THROUGH THE FCST CYCLE. LGT RAIN SHWRS EARLY ON IN THE VICINITY OF SYR AND RME WILL QUICKLY RETREAT AS A WARM FRONT LIFTS NORTH INTO NORTHERN NY. AS THE HEATING CYCLE BEGINS...WINDS WILL INCREASE FROM THE SOUTHWEST WITH GUSTS UP TO 25 KTS LIKELY UNDER STRONG BOUNDARY LAYER MIXING. WINDS WILL BEGIN TO WEAKEN BY EARLY EVENING WITH ONLY UPPER CI EXPECTED AFTER 04Z. OUTLOOK... MON...VFR. MON NIGHT/TUE/TUE NGT...MVFR/IFR RESTRICTIONS IN SHOWERS. WED...VFR. THURS...VFR. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS MOISTURE INCREASES AHEAD OF NEXT STORM SYSTEM TODAY THROUGH TUESDAY. .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...CMG AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
825 AM EDT SUN APR 13 2014 .SYNOPSIS... LIGHT SHOWERS WILL DRIFT OFF TO THE NORTH AS A WARM FRONT PUSHES THROUGH CENTRAL NEW YORK THIS MORNING. A WARM SOUTHWEST FLOW WILL PERSIST OVER THE AREA THROUGH MONDAY WITH HIGH TEMPERATURES REACHING INTO THE 70S TODAY AND MONDAY. A COLD FRONT WILL PASS THROUGH THE AREA ON TUESDAY PROVIDING A SOAKING RAIN. OVERNIGHT TEMPERATURES BEHIND THE COLD FRONT ON TUESDAY NIGHT WILL DROP DOWN INTO THE 20S. && .NEAR TERM /THROUGH TONIGHT/... 825 AM UPDATE...WE HAVE LOWERED POPS ACRS NRN ZONES AS MOST OF THE -SHRA ACTIVITY HAS MOVD OUT OF THE RGN. LOTS OF UPR CLD ACRS THE AREA TDA. RUC ADVERTISES 925 TEMPS OF 20-22C IN AN AXIS ACRS THE CNTRL SRN TIER AND FINGER LAKES...WHICH IF MIXED DOWN WITH FULL SUN WOULD RESULT IN MAXES OF 80-85. THESE 925 FCST TEMPS ARE A FEW DEG WARMER THAN OTHER GUIDANCE (WE NOTE +17C AT 925 FROM THE 12Z BUF SNDG). GIVEN THIS AND THE ABUNDANT CLD HI CLD CVR WE`LL LEAVE MAXES AS IS. PREV BLO... 5 AM UPDATE... MINOR UPDATE TO ADD IN SPRINKLES AND/OR ISOLD SHOWERS ACRS NEPA AND WRN CATS FORMING ON NOSE OF H8 LLJ. HV RMVD THUNDER MENTION FOR THIS MRNG FM ALL GRIDS AS NO LGTNG STRIKES NOTED IN THE LAST 4 HRS. ALL ELSE LOOKS TO BE ON TRACK AT THIS TIME WITH BULK OF THE PCPN LKLY TO BE NORTH OF CWA WITHIN THE NEXT COUPLE OF HRS. PREV DISCUSSION BLO... 330 AM UPDATE... WMFNT WL LIFT THRU CWA THIS MRNG, LVG AREA IN WARM SECTOR AND SWRLY FLOW. LGT RAIN SHOWERS EXPECTED ACRS NRN ZONES THIS MRNG WL LIFT NORTH AS BNDRY LIFTS THRU THE REGION. CLDS WL GRADUALLY BE ON THE DECREASE BUT WITH AREA IN INCRSG MID-LVL MOISTURE RIDING NORTH EXPECT CUMULUS TO DVLP AND RESULT IN PCLDY CONDS THROUGHOUT THE DAY. H8 TEMPS CLIMBING TO +12C EXPECTED TO YIELD ANOTHER SUMMERY DAY. HIGH TEMPS WL BE SVRL DEGREES WARMER THAN YDA WITH L/M 70S COMMON ACRS THE AREA - NEARLY 15-20 DEGREES ABV NORMAL. WARM SW FLOW WL CONTINUE TONIGHT AS CWA RMNS LOCKED INTO WM SECTOR. BY 12Z MONDAY EXPECT CDFNT TO BE LOCATED IN VICINITY OF THE THUMB OF LWR MICHIGAN AND SLIDING EAST. GOM WL BE WIDE OPEN TONIGHT WITH H8 WINDS DRAWING IN PW VALUES APPCHG 1 INCH BY 12Z MONDAY. THIS IS ALREADY 1-2 SD ABV NORMAL FOR THIS TIME OF YR. DWPT VALUES WL INCREASE INTO THE 50S TONIGHT WITH OVRNGT LOWS ONLY DROPPING INTO THE MID-50S. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... 330 AM UPDATE... FRONT WL APPCH EVER CLOSER DRG THE DAY MONDAY, BUT STILL RMN FAR ENUF TO THE WEST THAT PCPN WL BE HARD-PRESSED TO MV INTO CWA MUCH BFR 21Z. IT IS POSSIBLE THAT AN ISOLD SHOWER OR TWO WL OCCUR AFT 18Z AS LEAD S/WV TRACKS THRU THE AREA BUT BEST FRCG LOOKS TO BE ALONG FRONT TWD 00Z. HV BACKED OFF SLIGHTLY WITH POPS FOR MON AFTN TO ACCNT FOR SLOWER MVMNT OF CDFNT PER 00Z NAM AND EC. INSTABILITY IS PROGGED TO INCRS ON MONDAY WITH SHOWERS EXPECTED EARLY THAN GIVING WAY TO ISOLD CONVECTION BY LATE AFTN. GIVEN INCRSG MOISTURE ALONG WITH CLDS HV DROPPED MAX TEMPS BY A DEGREE OR TWO BUT STILL RANGING IN THE LWR TO UPR 70S. AN 80-DEGREE READING IS NOT OUT OF THE QUESTION. FROPA EXPECTED TO HOLD OFF UNTIL SOMETIME TUE MRNG, THUS HV BUMPED TEMPS AND DWPT VALUES UP FOR MON NGT. EXPECT MOST OF THE AREA TO BE LOCKED INTO SHOWERS WITH SOME THUNDER AFTER 06Z. MED RANGE MODELS GIVING SOME INDICATION OF LIGHTER PCPN OCCURRING IN SHADOWING AFFECTS IN SRLY FLOW ACRS CNTR SXN OF CWA TWD 12Z. THUS, EXPECT HIGHER QPF AMNTS BTWN 06Z AND 12Z TUE ACRS NW ZONES AND TERRAIN AREAS OF SERN ZONES. FROPA NOW EXPECTED TO HAPPEN DRG THE DAY ON TUE WITH RAINY DAY EXPECTED. HEAVIEST PCPN LOOKS TO FALL DRG THE MAIN PART OF THE DAY WITH STORM-TOTAL QPF AMNTS BTWN 12Z TUE-00Z WED ARND 1 INCH. THIS WL BE IN CONJUNCTION WITH RRQ OF 250MB JET STREAK LEADING TO STRONG FRCG OVR MOST OF CWA DRG THE DAY. TEMPS EXPECTED TO FALL DRG THE COURSE OF THE DAY WITH HIGH TEMPS OCCURRING AT DAYBREAK ACRS NRN ZONES, MID-MRNG OVR CNTRL SXNS AND EARLY AFTN ACRS NEPA. HV SIDED WITH NON-DIURNAL TREND OF MET/MAV GUIDANCE AS THEY SEEM TO BE MOST REASONABLE. 00Z EURO LOOKS WAY TOO COLD FOR TEMPS ON TUE WITH TEMPS DOWN INTO THE 20S AREAWIDE BY 00Z WED. TUE NGT EXPECTED TO BE VRY CLD WITH LOWS ULTIMATELY DROPPING INTO THE 20S AND POSSIBLY TEENS OVR NRN ONEIDA CNTY. ANY LINGERING PCPN WL MIX WITH AND EVENTUALLY CHG TO SNOW DRG THE OVRNGT WITH ONLY A DUSTING EXPECTED OVR HIGHER TERRAIN OF WRN CATS. SFC HIPRES QUICKLY BUILDS IN AFT 06Z. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... QUIET BUT BELOW NORMAL PERIOD SETTING UP EARLY ON AS CANADIAN HIGH PRESSURE SETTLES OVER THE REGION FOLLOWING TUESDAY/S COLD FRONT. HIGH TEMPS LOOK TO ONLY WARM INTO THE LOWER THE MIDDLE 40S ON WEDNESDAY...WITH SLIGHT MODERATION EXPECTED THROUGH THE DURATION OF THE WORK WEEK. NEXT CHANCE FOR PRECIP LOOKS TO ARRIVE NEXT WEEKEND AS SERIES OF TROUGHS CONSOLIDATE OVER THE NATION/S MIDSECTION. AS THIS OCCURS...BOTH THE GFS AND ECMWF SHOW DEVELOPING CYCLOGENESIS ACROSS THE MID MISS RVR VLY WITH THIS LOW GRADUALLY LIFTING NORTH WELL WEST OF OUR FCST AREA. THAT SAID...THE GFS SHOWS A MUCH MORE AMPLIFIED WOUND-UP CLOSED LOW SOLUTION WHILE THE ECMWF MAINTAINS A PROGRESSIVE OPEN WAVE. AS ONE CAN IMAGINE THE FORMER OFFERS A WETTER SOLUTION THAN THE LATTER. BASED ON THESE DIFFERENCES AND DISTANCE OUT INTO THE FCST PERIOD...NO SIGNIFICANT CHANGES MADE THIS MORNING. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR CONDITIONS EXPECTED THROUGH THE FCST CYCLE. LGT RAIN SHWRS EARLY ON IN THE VICINITY OF SYR AND RME WILL QUICKLY RETREAT AS A WARM FRONT LIFTS NORTH INTO NORTHERN NY. AS THE HEATING CYCLE BEGINS...WINDS WILL INCREASE FROM THE SOUTHWEST WITH GUSTS UP TO 25 KTS LIKELY UNDER STRONG BOUNDARY LAYER MIXING. WINDS WILL BEGIN TO WEAKEN BY EARLY EVENING WITH ONLY UPPER CI EXPECTED AFTER 04Z. OUTLOOK... MON...VFR. MON NIGHT/TUE/TUE NGT...MVFR/IFR RESTRICTIONS IN SHOWERS. WED...VFR. THURS...VFR. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS MOISTURE INCREASES AHEAD OF NEXT STORM SYSTEM TODAY THROUGH TUESDAY. .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...PVN NEAR TERM...PVN SHORT TERM...PVN LONG TERM...CMG AVIATION...CMG FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1027 PM EDT MON APR 14 2014 .SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1015 PM MONDAY... WARM MOIST AIR CONTINUES TO FILTER INTO CENTRAL NC THIS EVENING WITH DEWPOINTS INCREASING INTO THE LOWER TO MID 60S AS SOUTH TO SOUTHEASTERLY FLOW IS INCREASING IN ADVANCE OF A STRONG COLD FRONT... CURRENTLY EXTENDING FROM THE EASTERN GREAT LAKES REGION SOUTH-SOUTHWESTWARD TO THE AROUND NEW ORLEANS. THIS FRONT WILL CONTINUE PUSHING EASTWARD OVERNIGHT... APPROACHING THE CENTRAL TO SOUTHERN APPALACHIANS BY 12Z TUESDAY. THE WEAK PRE-FRONTAL BAND OF CONVECTION THAT MOVED ACROSS TN/GA/SC AND WESTERN NC EARLIER TODAY WEAKENED FURTHER THIS EVENING AND HAS LEFT AN OUTFLOW BOUNDARY ACROSS PORTIONS OF THE WESTERN PIEDMONT. NEW SHOWERS AND STORMS ARE NOW FORMING ON THE BOUNDARY. INSTABILITY IS INCREASE ACROSS THE AREA IN GENERAL... WITH A NOSE OF MLCAPE (SMALL AMOUNT 100-250 J/KG) EXTENDING UP TOWARDS THE DAVIDSON/ROWAN COUNTY LINE. THIS COUPLE WITH STRONG DEEP LAYER SHEAR (0-6 KM SHEAR OF AROUND 40-50 KTS) AND A FAVORABLE LOW LEVEL WIND PROFILE (0-1KM SRH OF 150-200 M2/S2) HAS YIELDED SOME WEAK ROTATION WITH THESE VERY SHALLOW SHOWERS/STORMS FROM TIME TO TIME. AT THIS TIME DO NOT THINK ANY WEAK ROTATION WILL RESULT IN ANY ISOLATED BRIEF TORNADOES AS THE UPDRAFTS DO NO APPEAR STRONG ENOUGH. THAT SAID... WE WILL NEED TO KEEP AN EYE ON THE RADAR FOR ANY QUICK SPIKE IN INTENSITY WITH THESE SHOWERS/STORMS SINCE THEY ARE INVOF THE REMNANT OUTFLOW BOUNDARY FROM EARLIER. GIVEN THE ABOVE MENTIONED DEEP SHEAR AND FAVORABLE ATLANTIC LOW LEVEL SOUTHEASTERLY INFLOW WE WILL NEED TO WATCH ANY CONVECTION THAT FORMS OVER THE AREA OVERNIGHT... ESPECIALLY WITH THE LATEST RAP SHOWING AS MUCH AS 500 J/KG OF MLCAPE MOVING INTO OUR SOUTH/SOUTHEASTERN HALF OF CENTRAL NC OVERNIGHT. LATEST HRRR AND RAP SHOW AN INCREASE IN ACTIVITY AFTER 06Z TONIGHT. THUS... WILL MAINTAIN HIGH POPS AFTER 06Z TONIGHT AND MAINTAIN MENTION OF SOME STRONG WIND GUSTS. EXPECT OVERNIGHT LOWS WILL BE WARM GIVEN THE INCREASING MOISTURE/CLOUD COVER. THUS... EXPECT LOW TEMPS WILL BE IN THE LOWER TO MID 60S. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40-50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST. STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING... KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32 MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... FOR WED THROUGH THU NIGHT: THE INTENSE BUT DAMPENING TROUGH WILL TRACK QUICKLY TO OUR NORTHEAST IN THE PREDAWN HOURS WED...AND WILL BE FOLLOWED BY GENERALLY FLAT SW FLOW OVER THE SOUTHEAST/MIDSOUTH/ CAROLINAS THROUGH WED. FORECAST SOUNDINGS ARE VERY DRY AND STABLE AS THE CENTER OF THE COOL SURFACE HIGH PRESSURE MOVES FROM THE OHIO VALLEY NORTHEASTWARD OVER THE ST LAWRENCE VALLEY WHILE NOSING DOWN THROUGH NC. EXPECT BREEZY AND COOL WINDS FROM THE NE WED... DIMINISHING LATE WED INTO THU AS THE MSLP GRADIENT RELAXES. LOW LEVEL THICKNESSES ARE EXPECTED TO PLUNGE TUE NIGHT TO OVER 70 M BELOW NORMAL...WITH ONLY MODEST RECOVERY DURING THE DAY... TRANSLATING TO HIGHS IN THE LOW-MID 50S. (AND THIS MAY EVEN BE OPTIMISTIC CONSIDERING THE PROJECTED 925 MB TEMPS BROUGHT DOWN DRY ADIABATICALLY YIELD HIGHS ONLY AROUND 50 OVER MUCH OF CENTRAL NC.) EXPECT MOSTLY CLEAR SKIES TO CONTINUE THROUGH THU NIGHT WITH DEEP DRY/STABLE AIR AS THE SLOWLY RETREATING AND MODIFYING SURFACE RIDGE NOSES INTO NC FROM THE NORTH... ALTHOUGH WE COULD START TO SEE PATCHY STRATUS LATE THU NIGHT WITH INCREASING ONSHORE-DIRECTED FLOW. LIGHT WINDS AND A CONTINUED ANOMALOUSLY COOL AIR MASS WILL FOSTER GOOD RADIATIONAL COOLING CONDITIONS... AND ANOTHER LIGHT FREEZE IS POSSIBLE WED NIGHT... PARTICULARLY IN THE RURAL AREAS OF THE PIEDMONT. NOT QUITE AS COOL THU WITH HIGHS EXPECTED TO BE 59-64. LOWS THU NIGHT 37-42 WITH RISING DEW POINTS. FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE. WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED. EXPECT TEMPS CLOSE TO NORMAL MON. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 800 PM MONDAY... MOSTLY VFR CONDITIONS REMAIN ACROSS THE REGION AT THIS HOUR...BUT THIS WILL CHANGE FAIRLY SOON AS AVIATION CONDITIONS DETERIORATE WITHIN A RAPIDLY MOISTENING AIR MASS AHEAD OF AN APPROACHING COLD FRONT. WIDELY SCATTERED SHOWERS WILL CONTINUE ACROSS THE REGION...WITH BRIEF SUB-VFR CONDITIONS OCCURRING WITHIN ANY SHOWER. IT STILL APPEARS THAT SHOWER COVERAGE WILL INCREASE AFTER MIDNIGHT AS THE LOW LEVEL FLOW STRENGTHENS EVEN MORE (GUSTS OF 20-25 KNOTS WILL BE POSSIBLE). REGARDLESS...CIGS SHOULD FALL INTO THE IFR TO LIFR RANGE OVER THE NEXT COUPLE OF HOURS AND THEN REMAIN THERE THROUGH THE MORNING HOURS. THERE COULD BE A BRIEF LULL IN THE PRECIP TUESDAY MORNING AND THIS IS WHEN CIGS MAY BRIEFLY RISE INTO THE MVFR RANGE. HOWEVER...THIS WILL BE SHORT-LIVED AS SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE ACROSS THE AREA FROM WEST TO EAST AHEAD AND ALONG THE COLD FRONT. FRONTAL PASSAGE IS EXPECTED TO OCCUR LATE TUESDAY AFTERNOON INTO EARLY TUESDAY EVENING (MAYBE JUST AFTER THE CURRENT TAF PERIOD IN THE EAST)...WITH CLOUDS GRADUALLY LIFTING AND CLEARING AS WINDS SHIFT TO THE NORTHWEST AND REMAIN GUSTY...LIKELY 25-30 KNOTS. OUTLOOK...CONDITIONS WILL IMPROVE TUESDAY NIGHT BEHIND THE DEPARTING FRONT AND THEN MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ007>010-021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...BSD SHORT TERM...DJF LONG TERM...HARTFIELD AVIATION...KRD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
835 PM EDT MON APR 14 2014 .SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM MONDAY... AS PRECIPITABLE WATER VALUES HAVE CLIMBED TO NEAR AN INCH...AND INSTABILITY HAS INCREASED DURING THE DAY WITH MSAS SHOWING LIFTED INDICES AROUND -2C AND MLCAPE ON THE SPC MESOANALYSIS A COUPLE OF HUNDRED J/KG...A FEW SHOWERS HAVE DEVELOPED OVER THE PIEDMONT IN UPPER DIFFLUENCE AS A MODEST MID-LEVEL SHORTWAVE MOVES THROUGH. THE LATEST HRRR WRF IS HANDLING THE LOCATION...COVERAGE...AND INTENSITY OF THESE SHOWERS FAIRLY WELL...AND THOUGH AN ISOLATED THUNDERSTORM IS POSSIBLE...MOSTLY THE RELATIVELY DEEP CONVECTION SHOULD REMAIN AS SHOWERS. OVERNIGHT...A GRADUAL INCREASE IN MOISTURE CONTINUES...WITH PRECIPITABLE WATER VALUES INCREASING TO NEAR 1.5 INCHES BY 12Z TUESDAY AS 850MB THETA-E VALUES INCREASE AS WELL. MID-LEVEL SHORTWAVES MOVING TOWARD CENTRAL NORTH CAROLINA SHOULD WEAKEN AS THEY APPROACH...AND THE NAM IN PARTICULAR FORECASTS 850MB LIFT TO DECREASE...BUT 850MB WINDS INCREASE LATE TONIGHT WHICH SHOULD ADD TO MOISTURE TRANSPORT AND LIFT...AND 0-3KM SHEAR INCREASES AS WELL TO AROUND 40KT PARTICULARLY IN THE SOUTHWEST PIEDMONT LATE. ALREADY... THE COVERAGE OF SHOWERS HAS INCREASED TOWARD THE FOOTHILLS...AND GRADUALLY DURING THE EVENING AND OVERNIGHT HOURS THE COVERAGE OF NUMEROUS OR GREATER SHOWERS AND ISOLATED THUNDERSTORMS SHOULD MOVE EAST ACROSS CENTRAL NORTH CAROLINA. THROUGH MIDNIGHT...THE AREA WITH BETTER COVERAGE OF SHOWERS SHOULD BE OVER THE FAR WESTERN PIEDMONT...THEN OVERNIGHT...EXPECT BETTER COVERAGE GRADUALLY EASTWARD. AS WINDS ALOFT INCREASE...AN ISOLATED STRONG STORM CANNOT BE RULED OUT...ESPECIALLY OVER THE SOUTHWEST PIEDMONT WHERE THE COMBINATION OF SHEAR AND 850MB WINDS AND LIFT IS EXPECTED TO BE BEST OVERNIGHT. ALSO...IT IS INTERESTING THAT THE NAM MOS GUIDANCE FORECASTS SUSTAINED WINDS TO 25KT AT KGSO AND EVEN THE GFS FORECASTS SUSTAINED SURFACE WINDS TO JUST BELOW 20KT LATE TONIGHT. A FEW DECENT GUSTS ARE POSSIBLE...IT WOULD SEEM...AS ANY HEAVIER SHOWER MOVES THROUGH OVERNIGHT. AROUND AND JUST AFTER 06Z... THE GFS BUFR SOUNDINGS SHOW A MOIST ADIABATIC PROFILE AT KGSO WITH WINDS JUST OFF THE SURFACE TO 40KT...AND THE NAM...WHILE DRIER...DOES HAVE A SLIGHTLY STEEPER LAPSE RATE. OVERNIGHT LOWS SHOULD BE WARM...IN THE LOWER TO MID 60S AHEAD OF THE FRONT. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 300 PM MONDAY... WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40-50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST. STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING... KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32 MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... FOR WED THROUGH THU NIGHT: THE INTENSE BUT DAMPENING TROUGH WILL TRACK QUICKLY TO OUR NORTHEAST IN THE PREDAWN HOURS WED...AND WILL BE FOLLOWED BY GENERALLY FLAT SW FLOW OVER THE SOUTHEAST/MIDSOUTH/ CAROLINAS THROUGH WED. FORECAST SOUNDINGS ARE VERY DRY AND STABLE AS THE CENTER OF THE COOL SURFACE HIGH PRESSURE MOVES FROM THE OHIO VALLEY NORTHEASTWARD OVER THE ST LAWRENCE VALLEY WHILE NOSING DOWN THROUGH NC. EXPECT BREEZY AND COOL WINDS FROM THE NE WED... DIMINISHING LATE WED INTO THU AS THE MSLP GRADIENT RELAXES. LOW LEVEL THICKNESSES ARE EXPECTED TO PLUNGE TUE NIGHT TO OVER 70 M BELOW NORMAL...WITH ONLY MODEST RECOVERY DURING THE DAY... TRANSLATING TO HIGHS IN THE LOW-MID 50S. (AND THIS MAY EVEN BE OPTIMISTIC CONSIDERING THE PROJECTED 925 MB TEMPS BROUGHT DOWN DRY ADIABATICALLY YIELD HIGHS ONLY AROUND 50 OVER MUCH OF CENTRAL NC.) EXPECT MOSTLY CLEAR SKIES TO CONTINUE THROUGH THU NIGHT WITH DEEP DRY/STABLE AIR AS THE SLOWLY RETREATING AND MODIFYING SURFACE RIDGE NOSES INTO NC FROM THE NORTH... ALTHOUGH WE COULD START TO SEE PATCHY STRATUS LATE THU NIGHT WITH INCREASING ONSHORE-DIRECTED FLOW. LIGHT WINDS AND A CONTINUED ANOMALOUSLY COOL AIR MASS WILL FOSTER GOOD RADIATIONAL COOLING CONDITIONS... AND ANOTHER LIGHT FREEZE IS POSSIBLE WED NIGHT... PARTICULARLY IN THE RURAL AREAS OF THE PIEDMONT. NOT QUITE AS COOL THU WITH HIGHS EXPECTED TO BE 59-64. LOWS THU NIGHT 37-42 WITH RISING DEW POINTS. FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE. WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED. EXPECT TEMPS CLOSE TO NORMAL MON. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 800 PM MONDAY... MOSTLY VFR CONDITIONS REMAIN ACROSS THE REGION AT THIS HOUR...BUT THIS WILL CHANGE FAIRLY SOON AS AVIATION CONDITIONS DETERIORATE WITHIN A RAPIDLY MOISTENING AIR MASS AHEAD OF AN APPROACHING COLD FRONT. WIDELY SCATTERED SHOWERS WILL CONTINUE ACROSS THE REGION...WITH BRIEF SUB-VFR CONDITIONS OCCURRING WITHIN ANY SHOWER. IT STILL APPEARS THAT SHOWER COVERAGE WILL INCREASE AFTER MIDNIGHT AS THE LOW LEVEL FLOW STRENGTHENS EVEN MORE (GUSTS OF 20-25 KNOTS WILL BE POSSIBLE). REGARDLESS...CIGS SHOULD FALL INTO THE IFR TO LIFR RANGE OVER THE NEXT COUPLE OF HOURS AND THEN REMAIN THERE THROUGH THE MORNING HOURS. THERE COULD BE A BRIEF LULL IN THE PRECIP TUESDAY MORNING AND THIS IS WHEN CIGS MAY BRIEFLY RISE INTO THE MVFR RANGE. HOWEVER...THIS WILL BE SHORT-LIVED AS SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE ACROSS THE AREA FROM WEST TO EAST AHEAD AND ALONG THE COLD FRONT. FRONTAL PASSAGE IS EXPECTED TO OCCUR LATE TUESDAY AFTERNOON INTO EARLY TUESDAY EVENING (MAYBE JUST AFTER THE CURRENT TAF PERIOD IN THE EAST)...WITH CLOUDS GRADUALLY LIFTING AND CLEARING AS WINDS SHIFT TO THE NORTHWEST AND REMAIN GUSTY...LIKELY 25-30 KNOTS. OUTLOOK...CONDITIONS WILL IMPROVE TUESDAY NIGHT BEHIND THE DEPARTING FRONT AND THEN MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ007>010-021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...DJF SHORT TERM...DJF LONG TERM...HARTFIELD AVIATION...KRD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
803 PM EDT MON APR 14 2014 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS TONIGHT AND TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE INTO THE AREA AND STALL INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 700 PM MONDAY...THE REMAINDER OF THE EVENING POPS WILL TAKE INTO ACCOUNT THE CURRENT PCPN PAINTED BY MOSAIC RADAR ALONG WITH ITS CURRENT AND FUTURE MOVEMENT. FOR POPS AFTER MIDNIGHT THROUGH DAYBREAK...HAVE FOLLOWED MORE CLOSELY TO THE HRRR OUTPUT MIMICKING PROGGED REFLECTIVITY ACROSS THE FA AS WELL AS THE LATEST SREF OVERNIGHT PROBABILITIES FOR MEASURABLE RAIN. IN ESSENCE...THE BEST SYNOPTIC/MESOSCALE UVVS TO REMAIN WEST AND NORTH OF THE FA DURING THE PRE-DAWN TUE HOURS. AND AS A RESULT...HAVE ALIGNED THE HIER POPS ACROSS THE NORTHERN AND WESTERN PORTIONS OF THE ILM CWA. THE EASTERN AND SOUTHERN PORTIONS OF THE ILM CWA YOU WILL FIND MUCH LOWER POPS. THIS PLAN OF ACTION ALIGNS UP NICELY WITH OUR NEIGHBORING CWAS. LATEST LIGHTNING OBSERVING NETWORK CONTINUES TO INDICATE A LACK OF ANY STRIKES UP TO THIS POINT. WILL THEREFORE CONTINUE WITHOUT INDICATING THUNDER FOR THE REMAINDER OF THIS EVENING. HOWEVER...DID INDICATE ISOLATED THUNDER DURING THE PRE- DAWN TUE HRS...AND CONTINUING INTO DAYLIGHT TUE MORNING. PROGGED OVERNIGHT TSTORM PARAMETERS RATHER WEAK BUT NEVERTHELESS PRESENT ENUF TO INCLUDE THUNDER. LATEST OBSERVED TEMPS/DEWPOINTS LOOKING AOK WITH THE CURRENT FORECAST AND SEE NO TWEAKING TO THE OVERNIGHT MINS AT THIS TIME. PREVIOUS DISCUSSION.................................... AS OF 300 PM MONDAY...SCATTERED SHOWERS HAVE DEVELOPED ACROSS THE AREA AS EXPECTED...THANKS TO MOIST ADVECTION ON S/SE WINDS AROUND A SURFACE HIGH PRESSURE CENTERED WELL OFFSHORE. SHOWERS HAVE DEVELOPED ALONG CONVERGENT BOUNDARIES...SINCE MORE WIDESPREAD ACTIVITY IS LIMITED BY A DECENT INVERSION ABOVE 800MB...AND PERSISTENT VERY DRY AIR IN THE MID-LEVELS. THIS INVERSION IS PROGGED TO SLOWLY ERODE THROUGH THE REMAINDER OF THE AFTN INTO THIS EVENING...AS MID-LEVEL THICKNESSES DECREASE IN ADVANCE OF AN APPROACHING UPPER LOW AND COLD FRONT. AT THE SAME TIME...MID-LEVELS WILL MOISTEN TONIGHT...AND THUS PRECIPITATION WILL HAVE THE POTENTIAL TO BECOME MORE WIDESPREAD THROUGH TONIGHT. HOWEVER...THE NATURE OF THE SHOWERS HAS BEEN PRIMARILY CONVECTIVE...ALBEIT OF SHALLOW NATURE. THUS WITH LOSS OF DIURNAL HEATING...THERE IS LIKELY TO BE A PERIOD OF REDUCED COVERAGE/ACTIVITY AFTER DARK BEFORE PRECIP RAMPS BACK UP AGAIN TOWARDS DAYBREAK. HAVE SHOWN THIS IN POP GRIDS...THE EXCEPTION BEING OVER THE WATERS WHERE ACTIVITY MAY BLOSSOM OVER THE GULF STREAM AND ADVECT INTO THE COASTAL WATERS (POSSIBLY ONSHORE AS WELL)...BUT THE MOST SIGNIFICANT RAINFALL WILL HOLD OFF UNTIL AFTER THIS PERIOD. TEMPS TONIGHT WILL REMAIN QUITE WARM AS SOUTHERLY WINDS INCREASE OVERNIGHT AS THE PRESSURE GRADIENT TIGHTENS. HAVE SHOWN A NON-TYPICAL DIURNAL CURVE...WITH MINS BEING REACHED A FEW HOURS AFTER MIDNIGHT...AND THEN RISING TOWARDS DAWN. LOWS WILL BE IN THE MID/UPR 60S...SUPPORTING VERY LITTLE DIURNAL CHANGE OVERNIGHT. && .SHORT TERM /6 AM TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...A STRONG COLD FRONT WILL MOVE MOVE THROUGH THE AREA TUESDAY BRINGING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. WINDS AT H8 ARE FORECAST TO BE IN THE 50 TO 55 KT RANGE WITH 0-3 KM SRH VALUES IN EXCESS OF 300 DURING THE AFTERNOON WHEN A SQUALL LINE IS EXPECTED TO MOVE THROUGH. MAX TEMPERATURES IN THE MID TO UPPER 70S WILL YIELD CAPE VALUES BELOW 1000 J/KG BUT THERE STILL IS SOME POTENTIAL FOR TEMPERATURES IN THE LOWER 80S WHICH WOULD YIELD CAPES AROUND 2000 J/KG AND ENHANCE SEVERE WEATHER POTENTIAL. SHOWERS AND STORMS END RAPIDLY BY ABOUT 03Z WEDNESDAY WITH FROPA FOLLOWED BY STRONG CAA RESULTING IN TEMPERATURES FALLING TO THE MID 30S TO AROUND 40. GUIDANCE HAS TRENDED COLDER TUESDAY NIGHT AND THERE IS SOME POTENTIAL FOR NEAR FREEZING TEMPERATURES NW BUT WILL WAIT TO SEE LATER MODEL RUNS TO SEE IF THE TREND CONTINUES. MAINLY CLEAR SKIES ARE EXPECTED WEDNESDAY WITH CAA CONTINUING ON N TO NE FLOW WHICH SHOULD YIELD MAX TEMPERATURES IN THE UPPER 50S TO LOWER 60S. AT THIS TIME...CONTINUED LIGHT WINDS AND A SLIGHT INCREASE IN CLOUDS...ESPECIALLY NE...SHOULD PRECLUDE A FREEZE BUT SOME FROST IS NOT OUT OF THE REALM OF POSSIBILITY...ESPECIALLY WESTERN AREAS. MINS WILL BE IN THE MID TO UPPER 30S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...STRONG HIGH PRESSURE CENTERED ACROSS NEW ENGLAND AND THE CANADIAN MARITIMES WILL REMAIN IN PLACE...AND MAY PERSIST INTO FRI...ALTHOUGH THE PRESSURES WILL BE LOWERING WITH TIME...AN INDICATION THAT THE WEDGE WILL BE WEAKENING WITH TIME. LATEST MODEL DATA INDICATES THE ORIENTATION OF THE WEDGE AND ITS EASTWARD EXTENSION DOES NOT SUPPORT THE DEVELOPMENT OF A COASTAL TROUGH NEAR THE COAST. THE DEVELOPING AND PRONOUNCED TROUGH INITIALLY OFFSHORE DOES MIGRATE CLOSER TO THE COAST BY THE WEEKEND AS THE UPSTREAM TROUGH STRUGGLES TO GAIN PROXIMITY AS THE UPPER SUPPORT REMAINS WELL AWAY FROM THE SOUTHEAST AND IS LIFTING NE AND FURTHER AWAY. THE CLOSER THE TROUGH IS TO THE COAST...THE GREATER THE ISENTROPIC LIFT POTENTIAL AND THE HIGHER THE RISK FOR RAINFALL. THE GFS AND EUROPEAN MODELS ARE SHOWING VERY DIVERSE SOLUTIONS THIS WEEKEND AND EARLY NEXT WEEK. THE EURO IS POINTING TO A WET FRI NIGHT AND SAT AS LOW PRESSURE MOVES OUT OF THE GULF OF MEXICO AND UP THE SOUTHEAST COAST. THE GFS KEEPS PRECIPITATION OFFSHORE DURING THIS TIME...BUT DOES BRING A WAVE OF LOW PRESSURE AND A SLUG OF DEEPER MOISTURE ACROSS THE FORECAST AREA LATE IN THE WEEKEND AND ON MON WITH A FRONTAL BOUNDARY STALLED NEAR IF NOT OVER THE FORECAST AREA. THE EURO ON THE OTHER HAND DOES NOT BRING THIS WAVE ACROSS THE AREA UNTIL MON NIGHT. THUS...THE WEEKEND AND EARLY NEXT WEEK FORECAST IS VERY MUCH A LOW CONFIDENCE FORECAST AND WILL BENEFIT FROM MODEL CONSISTENCY IF NOT A MORE UNIFIED SOLUTION WITH LATER RENDITIONS. TEMPERATURES WILL STILL BE COOL AND WELL BELOW NORMAL ON THU...WITH A SLOW MODERATING TREND THROUGH MON. HIGHS THU ARE NOT EXPECTED TO EXCEED THE LOWER TO PERHAPS MID 60S. WE WILL ADD ABOUT 5 DEGREES TO THAT ON FRI WITH TEMPS BACK TO NORMAL FOR THE WEEKEND AND MON... LOWER TO MID 70S. LOWS WILL BE CHILLY LATE WEEK...AROUND 40 THU NIGHT...NO FREEZE IS EXPECTED. MINIMUMS WILL BE ON THE UPSWING INTO EARLY NEXT WEEK...RETURNING TO NEAR NORMAL FRI NIGHT AND THEN ABOVE NORMAL SAT NIGHT AND SUN NIGHT. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...A MIX OF MVFR/IFR WITH POSSIBLE BRIEF PERIODS VFR EXPECTED THROUGH THE OVERNIGHT HOURS AS LOWERED CIGS AND ISOLATED SHOWERS MOVE THROUGH. LOWERED RESTRICTIONS CONTINUE INTO TUESDAY WITH INCREASING CHANCES FOR WIDESPREAD RAINFALL AND ISOLATED TO SCATTERED THUNDERSTORMS...SOME SEVERE. VFR/MVFR/IFR CONDITIONS ARE CURRENTLY AFFECTING THE AREA TAF SITES THIS EVENING AS VARYING CEILING HEIGHTS AND ISOLATED SHOWERS MOVE ACROSS THE AREA...WHICH IS EXPECTED TO PREVAIL THROUGH THE OVERNIGHT HOURS. SOUTH-SOUTHWEST WINDS WILL CONTINUE AOB 10 KTS WITH OCCASIONAL GUSTS AROUND 15-20 KTS POSSIBLE. ON TUESDAY CONFIDENCE REMAINS LOWERED REGARDING FLIGHT RESTRICTIONS GIVEN VARYING CLOUD HEIGHTS AND SHOWERS...OVERALL THOUGH ANTICIPATE MVFR/IFR AGAIN WITH INTERMITTENT IMPROVEMENTS TO VFR POSSIBLE. CHANCES INCREASE THROUGHOUT THE DAY FOR THUNDERSTORMS...WITH THE POSSIBILITY OF SOME BEING SEVERE...THOUGH CONFIDENCE IS LOW IF THE ANTICIPATED LINE OF CONVECTION WILL MAKE IT TO THE COAST. PRIMARY THREAT WITH POSSIBLE SEVERE WEATHER WILL BE DAMAGING WINDS. SOUTH-SOUTHWEST WINDS WILL CONTINUE ON TUESDAY AOB 10-15 KTS WITH HIGHER GUSTS POSSIBLE...ESPECIALLY IN STRONGER STORMS. EXTENDED OUTLOOK...BECOMING LATE VFR TUESDAY NIGHT...CONTINUING THROUGH THURSDAY. POSSIBLE FOG/STRATUS FRIDAY AND SATURDAY...LOW CONFIDENCE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 715 PM MONDAY...WIND SPEEDS STILL SLOW TO INCREASE ACROSS THE COASTAL WATERS DUE TO THE STABLE LOW LEVEL MARINE LAYER INDUCED BY THE COOL SHELF WATERS WITH READINGS IN THE LOW TO MID 60S. AS THE SFC PG TIGHTENS OVERNIGHT...WIND SPEEDS WILL FOLLOW SUIT. COULD SEE WIND GUSTS UP TO 25 KT LATE TONIGHT AS THE LOW LEVEL STABLE MARINE LAYER DECREASES IN DEPTH ALLOWING SOME OF THOSE HIER WINDS JUST OFF THE DECK TO DROP DOWN TO THE OCEAN SFC. THE SFC PRESSURE PATTERN WILL CONTINUE TO PRODUCE A SOUTHERLY WIND DIRECTION OVERNIGHT...AND INTO DAYLIGHT TUE. BUILDING SIGNIFICANT SEAS WILL HIGHLIGHT THE OVERNIGHT PERIOD AND CONTINUE INTO DAYLIGHT TUE. CURRENTLY...THE MAJORITY OF THE SIGNIFICANT SEAS MAKE-UP COMES FROM A SE-S PSEUDO SWELL FROM THE OFFSHORE WATERS. THIS A RESULT OF THE STRONGER WINDS FURTHER OFFSHORE HAVING A DECENT FETCH TO BUILD UPON. WIND DRIVEN WAVES WILL BECOME THE DOMINANT CONTRIBUTOR TO SIGNIFICANT SEAS BY DAYBREAK TUE. PREVIOUS DISCUSSION................................... AS OF 300 PM MONDAY...HIGH PRESSURE WELL OFFSHORE WILL SLOWLY RETREAT TO THE EAST THROUGH TONIGHT...AS A COLD FRONT APPROACHES FROM THE WEST. THIS WILL DRIVE THE CURRENT 10 KT S/SE WINDS UPWARD THROUGH THE PERIOD...BECOMING 15-20 KTS TONIGHT WITH A SLIGHT VEERING TO THE SOUTH. THESE STRONGER WINDS AND CONTINUED LONG DURATION FETCH AROUND THE HIGH PRESSURE WILL FORCE WAVE HEIGHTS TO AMPLIFY TONIGHT. EXPECT WAVE HEIGHTS TO GROW TO 4-6 FT OVERNIGHT...AND THE SMALL CRAFT ADVISORY HAS BEEN EXTENDED TO BEGIN AT 8PM TONIGHT FOR ALL THE COASTAL WATERS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED THROUGH MUCH OF THE PERIOD WITH S TO SW WINDS OF 20 TO 25 KT TUESDAY WHICH WILL SHIFT TO N TO NE AFTER THE FROPA TUESDAY NIGHT AND INCREASE TO 25 TO 30 KT. N TO NE WINDS WILL CONTINUE THROUGH WED NIGHT AS THEY GRADUALLY DIMINISH TO 15 TO 20 KT. SEAS WILL BUILD TO 6 TO 8 FT ON THE OPEN WATERS TUESDAY...MAY RELAX A LITTLE AS THE FRONT GOES THROUGH...THEN BUILD AS HIGH AS 9 FT TUESDAY NIGHT. SEAS WILL SLOWLY SUBSIDE WEDNESDAY AND WEDNESDAY NIGHT BUT RESIDUAL 6 FOOTERS ARE POSSIBLE AT 20 NM AROUND DAYBREAK THURSDAY. FOR NOW SCA HAS BEEN EXTENDED THROUGH 2 AM THURSDAY BUT MAY NEED TO BE EXTENDED FURTHER IN TIME IN LATER FORECASTS. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...A PROLONGED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS...ASSOCIATED WITH A COOL WEDGE OF HIGH PRESSURE AND ITS ASSOCIATED TIGHT PRESSURE GRADIENT...IS EXPECTED TO DROP BELOW THRESHOLDS THU NIGHT OR FRI. SEAS OF 6 FT ACROSS PORTIONS OF THE OUTER WATERS WILL BE THE LAST TO DROP BELOW THRESHOLD. THE JUXTAPOSITION OF A DEVELOPING COASTAL TROUGH MAY COMPLICATE THE WIND FORECAST FRI THROUGH SAT. AT THIS TIME...WILL KEEP NE WINDS THROUGHOUT THE PERIOD...HIGHEST THU AND THU NIGHT...UP TO 20 TO 25 KT. SEAS WILL BE HIGHEST DURING THIS TIME AS WELL...UP TO 5 TO 7 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT THURSDAY FOR AMZ250-252- 254-256. && $$ SYNOPSIS...RAN NEAR TERM...DCH/JDW SHORT TERM...RAN LONG TERM...RJD AVIATION...SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
738 PM EDT MON APR 14 2014 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS TONIGHT AND TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE INTO THE AREA AND STALL INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 700 PM MONDAY...THE REMAINDER OF THE EVENING POPS WILL TAKE INTO ACCOUNT THE CURRENT PCPN PAINTED BY MOSAIC RADAR ALONG WITH ITS CURRENT AND FUTURE MOVEMENT. FOR POPS AFTER MIDNIGHT THROUGH DAYBREAK...HAVE FOLLOWED MORE CLOSELY TO THE HRRR OUTPUT MIMICKING PROGGED REFLECTIVITY ACROSS THE FA AS WELL AS THE LATEST SREF OVERNIGHT PROBABILITIES FOR MEASURABLE RAIN. IN ESSENCE...THE BEST SYNOPTIC/MESOSCALE UVVS TO REMAIN WEST AND NORTH OF THE FA DURING THE PRE-DAWN TUE HOURS. AND AS A RESULT...HAVE ALIGNED THE HIER POPS ACROSS THE NORTHERN AND WESTERN PORTIONS OF THE ILM CWA. THE EASTERN AND SOUTHERN PORTIONS OF THE ILM CWA YOU WILL FIND MUCH LOWER POPS. THIS PLAN OF ACTION ALIGNS UP NICELY WITH OUR NEIGHBORING CWAS. LATEST LIGHTNING OBSERVING NETWORK CONTINUES TO INDICATE A LACK OF ANY STRIKES UP TO THIS POINT. WILL THEREFORE CONTINUE WITHOUT INDICATING THUNDER FOR THE REMAINDER OF THIS EVENING. HOWEVER...DID INDICATE ISOLATED THUNDER DURING THE PRE- DAWN TUE HRS...AND CONTINUING INTO DAYLIGHT TUE MORNING. PROGGED OVERNIGHT TSTORM PARAMETERS RATHER WEAK BUT NEVERTHELESS PRESENT ENUF TO INCLUDE THUNDER. LATEST OBSERVED TEMPS/DEWPOINTS LOOKING AOK WITH THE CURRENT FORECAST AND SEE NO TWEAKING TO THE OVERNIGHT MINS AT THIS TIME. PREVIOUS DISCUSSION................................................ AS OF 300 PM MONDAY...SCATTERED SHOWERS HAVE DEVELOPED ACROSS THE AREA AS EXPECTED...THANKS TO MOIST ADVECTION ON S/SE WINDS AROUND A SURFACE HIGH PRESSURE CENTERED WELL OFFSHORE. SHOWERS HAVE DEVELOPED ALONG CONVERGENT BOUNDARIES...SINCE MORE WIDESPREAD ACTIVITY IS LIMITED BY A DECENT INVERSION ABOVE 800MB...AND PERSISTENT VERY DRY AIR IN THE MID-LEVELS. THIS INVERSION IS PROGGED TO SLOWLY ERODE THROUGH THE REMAINDER OF THE AFTN INTO THIS EVENING...AS MID-LEVEL THICKNESSES DECREASE IN ADVANCE OF AN APPROACHING UPPER LOW AND COLD FRONT. AT THE SAME TIME...MID-LEVELS WILL MOISTEN TONIGHT...AND THUS PRECIPITATION WILL HAVE THE POTENTIAL TO BECOME MORE WIDESPREAD THROUGH TONIGHT. HOWEVER...THE NATURE OF THE SHOWERS HAS BEEN PRIMARILY CONVECTIVE...ALBEIT OF SHALLOW NATURE. THUS WITH LOSS OF DIURNAL HEATING...THERE IS LIKELY TO BE A PERIOD OF REDUCED COVERAGE/ACTIVITY AFTER DARK BEFORE PRECIP RAMPS BACK UP AGAIN TOWARDS DAYBREAK. HAVE SHOWN THIS IN POP GRIDS...THE EXCEPTION BEING OVER THE WATERS WHERE ACTIVITY MAY BLOSSOM OVER THE GULF STREAM AND ADVECT INTO THE COASTAL WATERS (POSSIBLY ONSHORE AS WELL)...BUT THE MOST SIGNIFICANT RAINFALL WILL HOLD OFF UNTIL AFTER THIS PERIOD. TEMPS TONIGHT WILL REMAIN QUITE WARM AS SOUTHERLY WINDS INCREASE OVERNIGHT AS THE PRESSURE GRADIENT TIGHTENS. HAVE SHOWN A NON-TYPICAL DIURNAL CURVE...WITH MINS BEING REACHED A FEW HOURS AFTER MIDNIGHT...AND THEN RISING TOWARDS DAWN. LOWS WILL BE IN THE MID/UPR 60S...SUPPORTING VERY LITTLE DIURNAL CHANGE OVERNIGHT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...A STRONG COLD FRONT WILL MOVE MOVE THROUGH THE AREA TUESDAY BRINGING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. WINDS AT H8 ARE FORECAST TO BE IN THE 50 TO 55 KT RANGE WITH 0-3 KM SRH VALUES IN EXCESS OF 300 DURING THE AFTERNOON WHEN A SQUALL LINE IS EXPECTED TO MOVE THROUGH. MAX TEMPERATURES IN THE MID TO UPPER 70S WILL YIELD CAPE VALUES BELOW 1000 J/KG BUT THERE STILL IS SOME POTENTIAL FOR TEMPERATURES IN THE LOWER 80S WHICH WOULD YIELD CAPES AROUND 2000 J/KG AND ENHANCE SEVERE WEATHER POTENTIAL. SHOWERS AND STORMS END RAPIDLY BY ABOUT 03Z WEDNESDAY WITH FROPA FOLLOWED BY STRONG CAA RESULTING IN TEMPERATURES FALLING TO THE MID 30S TO AROUND 40. GUIDANCE HAS TRENDED COLDER TUESDAY NIGHT AND THERE IS SOME POTENTIAL FOR NEAR FREEZING TEMPERATURES NW BUT WILL WAIT TO SEE LATER MODEL RUNS TO SEE IF THE TREND CONTINUES. MAINLY CLEAR SKIES ARE EXPECTED WEDNESDAY WITH CAA CONTINUING ON N TO NE FLOW WHICH SHOULD YIELD MAX TEMPERATURES IN THE UPPER 50S TO LOWER 60S. AT THIS TIME...CONTINUED LIGHT WINDS AND A SLIGHT INCREASE IN CLOUDS...ESPECIALLY NE...SHOULD PRECLUDE A FREEZE BUT SOME FROST IS NOT OUT OF THE REALM OF POSSIBILITY...ESPECIALLY WESTERN AREAS. MINS WILL BE IN THE MID TO UPPER 30S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...STRONG HIGH PRESSURE CENTERED ACROSS NEW ENGLAND AND THE CANADIAN MARITIMES WILL REMAIN IN PLACE...AND MAY PERSIST INTO FRI...ALTHOUGH THE PRESSURES WILL BE LOWERING WITH TIME...AN INDICATION THAT THE WEDGE WILL BE WEAKENING WITH TIME. LATEST MODEL DATA INDICATES THE ORIENTATION OF THE WEDGE AND ITS EASTWARD EXTENSION DOES NOT SUPPORT THE DEVELOPMENT OF A COASTAL TROUGH NEAR THE COAST. THE DEVELOPING AND PRONOUNCED TROUGH INITIALLY OFFSHORE DOES MIGRATE CLOSER TO THE COAST BY THE WEEKEND AS THE UPSTREAM TROUGH STRUGGLES TO GAIN PROXIMITY AS THE UPPER SUPPORT REMAINS WELL AWAY FROM THE SOUTHEAST AND IS LIFTING NE AND FURTHER AWAY. THE CLOSER THE TROUGH IS TO THE COAST...THE GREATER THE ISENTROPIC LIFT POTENTIAL AND THE HIGHER THE RISK FOR RAINFALL. THE GFS AND EUROPEAN MODELS ARE SHOWING VERY DIVERSE SOLUTIONS THIS WEEKEND AND EARLY NEXT WEEK. THE EURO IS POINTING TO A WET FRI NIGHT AND SAT AS LOW PRESSURE MOVES OUT OF THE GULF OF MEXICO AND UP THE SOUTHEAST COAST. THE GFS KEEPS PRECIPITATION OFFSHORE DURING THIS TIME...BUT DOES BRING A WAVE OF LOW PRESSURE AND A SLUG OF DEEPER MOISTURE ACROSS THE FORECAST AREA LATE IN THE WEEKEND AND ON MON WITH A FRONTAL BOUNDARY STALLED NEAR IF NOT OVER THE FORECAST AREA. THE EURO ON THE OTHER HAND DOES NOT BRING THIS WAVE ACROSS THE AREA UNTIL MON NIGHT. THUS...THE WEEKEND AND EARLY NEXT WEEK FORECAST IS VERY MUCH A LOW CONFIDENCE FORECAST AND WILL BENEFIT FROM MODEL CONSISTENCY IF NOT A MORE UNIFIED SOLUTION WITH LATER RENDITIONS. TEMPERATURES WILL STILL BE COOL AND WELL BELOW NORMAL ON THU...WITH A SLOW MODERATING TREND THROUGH MON. HIGHS THU ARE NOT EXPECTED TO EXCEED THE LOWER TO PERHAPS MID 60S. WE WILL ADD ABOUT 5 DEGREES TO THAT ON FRI WITH TEMPS BACK TO NORMAL FOR THE WEEKEND AND MON... LOWER TO MID 70S. LOWS WILL BE CHILLY LATE WEEK...AROUND 40 THU NIGHT...NO FREEZE IS EXPECTED. MINIMUMS WILL BE ON THE UPSWING INTO EARLY NEXT WEEK...RETURNING TO NEAR NORMAL FRI NIGHT AND THEN ABOVE NORMAL SAT NIGHT AND SUN NIGHT. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 18Z...A STABLE LAYER AROUND 6500 FT HAS KEPT THE ATMOSPHERE A BIT CAPPED...BUT THAT STABLE LAYER SHOULD DISSIPATE THIS EVENING WITH MORE WIDESPREAD CONVECTION EXPECTED TO BREAK OUT AFTER MIDNIGHT. CEILINGS WILL LOWER WITH THE COMMENCEMENT OF PRECIP...POSSIBLY IFR CONDITIONS INLAND. WINDS WILL STAY ABOVE 7-8 KTS OVERNIGHT...IN FACT THEY WILL INCREASE TOWARD MORNING AS THE GRADIENT TIGHTENS AHEAD OF THE FRONT. TUESDAY...CONVECTION WILL BE IN AND OUT WITH DECENT COVERAGE. MODELS INDICATE WE WILL GET ENOUGH SOLAR INSOLATION AND WARM AIR ADVECTION TO SUPPORT POSSIBLE STRONG STORMS AFTER MIDDAY...STARTING FROM THE SOUTHWEST. CAPE COULD APPROACH 1000 J/KG WITH 55 KTS AT 2500 FEET. THE MARINE LAYER MAY SPARE THE COAST FROM STRONG STORMS IF THEY WAIT TO ARRIVE BY LATE AFTERNOON OR EVENING. EXTENDED OUTLOOK...BECOMING VFR TUESDAY NIGHT...CONTINUING THROUGH THURSDAY. POSSIBLE FOG/STRATUS FRIDAY AND SATURDAY...LOW CONFIDENCE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 715 PM MONDAY...WIND SPEEDS STILL SLOW TO INCREASE ACROSS THE COASTAL WATERS DUE TO THE STABLE LOW LEVEL MARINE LAYER INDUCED BY THE COOL SHELF WATERS WITH READINGS IN THE LOW TO MID 60S. AS THE SFC PG TIGHTENS OVERNIGHT...WIND SPEEDS WILL FOLLOW SUIT. COULD SEE WIND GUSTS UP TO 25 KT LATE TONIGHT AS THE LOW LEVEL STABLE MARINE LAYER DECREASES IN DEPTH ALLOWING SOME OF THOSE HIER WINDS JUST OFF THE DECK TO DROP DOWN TO THE OCEAN SFC. THE SFC PRESSURE PATTERN WILL CONTINUE TO PRODUCE A SOUTHERLY WIND DIRECTION OVERNIGHT...AND INTO DAYLIGHT TUE. BUILDING SIGNIFICANT SEAS WILL HIGHLIGHT THE OVERNIGHT PERIOD AND CONTINUE INTO DAYLIGHT TUE. CURRENTLY...THE MAJORITY OF THE SIGNIFICANT SEAS MAKE-UP COMES FROM A SE-S PSEUDO SWELL FROM THE OFFSHORE WATERS. THIS A RESULT OF THE STRONGER WINDS FURTHER OFFSHORE HAVING A DECENT FETCH TO BUILD UPON. WIND DRIVEN WAVES WILL BECOME THE DOMINANT CONTRIBUTOR TO SIGNIFICANT SEAS BY DAYBREAK TUE. PREVIOUS DISCUSSION.............................................. AS OF 300 PM MONDAY...HIGH PRESSURE WELL OFFSHORE WILL SLOWLY RETREAT TO THE EAST THROUGH TONIGHT...AS A COLD FRONT APPROACHES FROM THE WEST. THIS WILL DRIVE THE CURRENT 10 KT S/SE WINDS UPWARD THROUGH THE PERIOD...BECOMING 15-20 KTS TONIGHT WITH A SLIGHT VEERING TO THE SOUTH. THESE STRONGER WINDS AND CONTINUED LONG DURATION FETCH AROUND THE HIGH PRESSURE WILL FORCE WAVE HEIGHTS TO AMPLIFY TONIGHT. EXPECT WAVE HEIGHTS TO GROW TO 4-6 FT OVERNIGHT...AND THE SMALL CRAFT ADVISORY HAS BEEN EXTENDED TO BEGIN AT 8PM TONIGHT FOR ALL THE COASTAL WATERS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED THROUGH MUCH OF THE PERIOD WITH S TO SW WINDS OF 20 TO 25 KT TUESDAY WHICH WILL SHIFT TO N TO NE AFTER THE FROPA TUESDAY NIGHT AND INCREASE TO 25 TO 30 KT. N TO NE WINDS WILL CONTINUE THROUGH WED NIGHT AS THEY GRADUALLY DIMINISH TO 15 TO 20 KT. SEAS WILL BUILD TO 6 TO 8 FT ON THE OPEN WATERS TUESDAY...MAY RELAX A LITTLE AS THE FRONT GOES THROUGH...THEN BUILD AS HIGH AS 9 FT TUESDAY NIGHT. SEAS WILL SLOWLY SUBSIDE WEDNESDAY AND WEDNESDAY NIGHT BUT RESIDUAL 6 FOOTERS ARE POSSIBLE AT 20 NM AROUND DAYBREAK THURSDAY. FOR NOW SCA HAS BEEN EXTENDED THROUGH 2 AM THURSDAY BUT MAY NEED TO BE EXTENDED FURTHER IN TIME IN LATER FORECASTS. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...A PROLONGED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS...ASSOCIATED WITH A COOL WEDGE OF HIGH PRESSURE AND ITS ASSOCIATED TIGHT PRESSURE GRADIENT...IS EXPECTED TO DROP BELOW THRESHOLDS THU NIGHT OR FRI. SEAS OF 6 FT ACROSS PORTIONS OF THE OUTER WATERS WILL BE THE LAST TO DROP BELOW THRESHOLD. THE JUXTAPOSITION OF A DEVELOPING COASTAL TROUGH MAY COMPLICATE THE WIND FORECAST FRI THROUGH SAT. AT THIS TIME...WILL KEEP NE WINDS THROUGHOUT THE PERIOD...HIGHEST THU AND THU NIGHT...UP TO 20 TO 25 KT. SEAS WILL BE HIGHEST DURING THIS TIME AS WELL...UP TO 5 TO 7 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT THURSDAY FOR AMZ250-252- 254-256. && $$ SYNOPSIS...RAN NEAR TERM...DCH/JDW SHORT TERM...RAN LONG TERM...RJD AVIATION...SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
351 PM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN INTO MONDAY. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM SUNDAY...HIGH PRESSURE CENTERED WELL OFFSHORE AND A BUILDING MID-LEVEL RIDGE HAS CREATED ANOTHER BEAUTIFUL MID-SPRING DAY ACROSS THE CAROLINAS. SOME INCREASED MOISTURE HAS HELPED SPAWN WIDESPREAD SCT/BKN DIURNAL CU ALONG AND AHEAD OF THE WESTWARD ADVANCING SEA BREEZE BOUNDARY. HRRR STILL SUGGESTS A FEW SHOWERS WILL DEVELOP WITHIN THIS CU TODAY BEFORE LOSS OF HEATING...BUT A SIGNIFICANT SUBSIDENCE INVERSION ABOVE 800MB IS PREVENTING MUCH VERTICAL DEPTH TO THE CU...AND THE MID-LEVELS REMAIN EXCEEDINGLY DRY. THUS...HAVE KEPT POP TO SILENT AND JUST CARRIED A TOKEN 5% ALONG THE SEA BREEZE UNTIL NIGHTFALL. ANY PRECIP CHANCES...ALONG WITH CONVECTIVE CLOUD COVER...WILL ERODE AFTER DARK WITH LOSS OF HEATING. WINDS WILL REMAIN ELEVATED TONIGHT WHICH ACT TO PUMP ADDITIONAL MOISTURE INTO THE LOW LEVELS OF THE ATMOSPHERIC COLUMN. ONCE AGAIN THERE MAY BE A FOG CONCERN TONIGHT. HOWEVER...THESE SAME WINDS WILL KEEP TEMPS ELEVATED...CREATING SURFACE DEWPOINT DEPRESSIONS SEVERAL DEGREES ABOVE 0. ADDITIONALLY...LLJ IS PROGGED TO RISE TO 25-30 KTS...ABOUT 10 KTS HIGHER THAN LAST NIGHT...WHICH WOULD LIKELY HELP MIX OUT MUCH IN THE WAY OF FOG. NEAR-SURFACE HYDROLAPSE RATES ARE ALSO MUCH LESS FAVORABLE. THEREFORE...HAVE KEPT ANY MENTION OF FOG OUT OF THE WX GRIDS...BUT SHALLOW FOG WILL BE POSSIBLE...ESPECIALLY INLAND. LOWS TONIGHT WILL STAY QUITE WARM ON THE SOUTHERLY WINDS...WITH LOWS DROPPING ONLY INTO THE LOW 60S ACROSS THE EASTERN HALF OF THE CWA...UPPER 50S IN THE FAR WESTERN ZONES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...HIGH PRESSURE WILL SHIFT OFF THE COAST MONDAY AS A COLD FRONT APPROACHES FROM THE WEST AND PASSES THROUGH THE AREA LATE TUESDAY. THE RESULT WILL BE INCREASING CLOUDS ON MONDAY WITH THE POSSIBILITY OF ISOLATED TO SCATTERED AFTERNOON SHOWERS AND POSSIBLY THUNDERSTORMS. MAX TEMPERATURES WILL REACH THE MID 70S TO AROUND 80. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE IN LOW LEVEL CONFLUENT FLOW MONDAY NIGHT AS THE FRONT CONTINUES TO APPROACH FROM THE WEST. LOWS WILL FALL TO THE LOW TO MIDDLE 60S UNDER A MAINLY CLOUDY SKY. NUMEROUS SHOWERS AND THUNDERSTORMS ARE ON TAP FOR TUESDAY INTO THE EARLY EVENING AS THE FRONT MOVES THROUGH THE AREA. WHILE WINDS AT H8 AND H9 ARE NOT OVERLY IMPRESSIVE...PEAKING AROUND 50 KT AT H8 AROUND 18Z...STORM RELATIVE HELICITY VALUES PEAK IN THE 250 TO 350 RANGE. GIVEN FORECAST MAX TEMPERATURES IN THE MIDDLE TO PERHAPS UPPER 70S...CAPE VALUES AROUND 1000 J/KG ARE ON TAP. THESE FACTORS COMBINED MAKE SEVERE THUNDERSTORMS A POSSIBILITY TUESDAY. A POTENTIAL FURTHER COMPLICATION FOR TUESDAY IS TEMPERATURES. TEXT MOS BULLETINS ARE GIVING MAX TEMPERATURES IN THE LOW TO MIDDLE 80S. UNLESS THERE ARE SIGNIFICANT BREAKS IN THE CLOUD COVER TUESDAY...THIS IS NOT EXPECTED TO HAPPEN BUT IF IT DID...THE RESULTING CAPE VALUES WOULD REACH OR EXCEED 2500 J/KG. THAT WOULD GREATLY ENHANCE SEVERE WEATHER POTENTIAL TUESDAY. THE FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY EVENING AND BRING A RAPID END TO THE WIDESPREAD SHOWERS AND STORMS. STRONG CAA SETS UP LATE AND MINS WILL FALL INTO THE LOW TO MID 40S MOST AREAS EXCEPT FOR A FEW UPPER 40S SOUTH AND EAST. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 300 PM SUNDAY...TWO OPPORTUNITIES FOR RAINFALL IN THE UPCOMING WEEK. ONE JUST PRIOR TO THE START OF THIS FORECAST PERIOD AND ANOTHER WITH A DEVELOPING COASTAL TROUGH LATE IN THE WEEK AND AHEAD OF A COLD FRONT. THE PASSAGE OF A COLD FRONT SAT NIGHT SHOULD END THE RISK FOR SHOWERS AND THUNDERSTORMS. IN THE WAKE OF A STRONG COLD FRONT...CHILLY HIGH PRESSURE WILL BUILD ACROSS THE AREA AND STRENGTHEN ACROSS NEW ENGLAND...EVOLVING INTO A PERSISTENT WEDGE WED AND THU. NE TO E FLOW IN THE LOWEST 5-6 KFT WILL BE TOPPED BY A WSW TO W FLOW. HOWEVER...PRECIPITABLE WATER VALUES WILL BE AS LOW AS A QUARTER OF AN INCH AND THE DRY AIR IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE LOOK FORMIDABLE. THEREFORE... WILL REFRAIN FROM ANY MENTION OF PRECIPITATION IN THE MIDDLE OF THE WEEK. HOWEVER...PATTERN IS CONDUCIVE FOR THE DEVELOPMENT OF LOWER CLOUDS...ESPECIALLY AS THE LOW-LEVEL FLOW TURNS EASTERLY WED NIGHT AND THU. AS THE WEDGE REORIENTS ITSELF THU NIGHT AND FRI...WE WILL HAVE TO WATCH FOR THE DEVELOPMENT OF A COASTAL TROUGH. THE LONG TERM MODELS HAVE BEEN CONSISTENT WITH THE DEVELOPMENT OF THIS FEATURE...BUT DO DIFFER AS TO ITS JUXTAPOSITION. AS A COLD FRONT APPROACHES...THE WEDGE SHOULD BEGIN TO ERODE FRI AND FRI NIGHT AND THE COASTAL TROUGH SHOULD BE DRAWN TO A POSITION VERY NEAR...IF NOT ON THE COAST. THUS WILL TREND POPS HIGHER DURING THIS TIME. MIXED LAYER CAPE VALUES DO INCREASE FRI INTO SAT AHEAD OF THE FRONT AND WILL INCLUDE MENTION OF THUNDERSTORMS. IN THE WAKE OF COLD FRONTAL PASSAGE SAT NIGHT...DRIER AND MORE STABLE AIR MAY BE SLOW TO ARRIVE FOR SUN WITH PERHAPS AN UPPER LEVEL FEATURE TRAVERSING THE AREA AS MAIN UPPER LOW MOVES ACROSS THE GREAT LAKES AND NORTHEAST. COLUMN LOOKS MUCH TOO DRY BELOW 10 KFT TO SUPPORT RAINFALL AND SO WILL KEEP POPS BELOW THRESHOLD FOR THE LAST DAY OF THE UPCOMING WEEKEND. TEMPERATURES WILL BE COOL FOR MUCH OF THE LONG TERM FORECAST. TEMPERATURES WILL BE MUCH BELOW NORMAL WED AND THU AND MAXIMUMS MAY NOT EXCEED 60 DEGREES IN SOME AREAS. LOWS WED NIGHT AND THU NIGHT WILL BE WELL DOWN IN THE 40S AND MAY DROP INTO THE UPPER 30S IN SOME INLAND SPOTS. TEMPS WILL RECOVER SLOWLY FRI AND INTO THE WEEKEND AND SHOULD BE NEAR NORMAL FOR THE UPCOMING WEEKEND. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 18Z...COMBINATION OF THE MEAN WIND AND THE SEA BREEZE WILL CONTINUE TO CREATE S/SE WINDS THROUGH THE AFTN...STRONGEST AT THE COASTAL TERMINALS. DIURNAL CU ALONG AND AHEAD OF THE SEA BREEZE BOUNDARY WILL BECOME BKN...ESPECIALLY INLAND...BUT VFR WILL REMAIN THROUGH NIGHTFALL. THE HIGH-RES HRRR CONTINUES TO DEVELOP A FEW SHOWERS ACROSS THE AREA THIS AFTN...BUT BELIEVE THE AIR ALOFT IS TOO DRY TO SUPPORT ANYTHING MORE THAN AN ISOLATED SPRINKLE...SO HAVE NOT ADDED A MENTION INTO ANY TAF. WINDS WILL REMAIN ELEVATED TONIGHT WHICH SHOULD PREVENT MUCH IN THE WAY OF FOG LOCALLY...BUT SOME RESTRICTIONS ARE POSSIBLE...ESPECIALLY INLAND WHERE SURFACE DEWPOINT DEPRESSIONS WILL BE LESS THAN NEAR THE COAST AND WINDS WILL BE LIGHTER. HAVE ADDED A TEMPO MVFR GROUP AT FLO/LBT...ALONG WITH SOME SCT IFR STRATUS SINCE WINDS OF 25-30 KTS ABOVE THE NOCTURNAL INVERSION COULD FORCE A STRATUS LAYER AS OPPOSED TO FOG. SOME STRATUS MAY ALSO ADVECT ONSHORE NEAR THE MYRTLES TOWARDS MORNING. VFR WILL RETURN ON MONDAY. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS LATE MONDAY THROUGH TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. VFR WEDNESDAY AND THURSDAY. POSSIBLE FOG/STRATUS THURSDAY NIGHT INTO FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM SUNDAY...HIGH PRESSURE EXTENDING BACK ACROSS THE COASTAL WATERS FROM WELL OFFSHORE WILL MAINTAIN ITS INFLUENCE LOCALLY THROUGH TONIGHT. A VERY WEAK PRESSURE GRADIENT HAS KEPT WINDS BELOW 10 KTS TODAY...BUT THESE WILL RISE SLOWLY TONIGHT TO 10-15 KTS FROM THE S/SE AROUND THE HIGH PRESSURE. THIS COMBINATION OF INCREASED WINDS AND A CONTINUING LOW-AMPLITUDE SE GROUND SWELL WILL DRIVE SEAS UP TO 2-4 FT BY THE END OF THE PERIOD. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...INCREASING WINDS AND SEAS ARE EXPECTED THROUGH THE PERIOD AS A COLD FRONT APPROACHES FROM THE WEST MONDAY AND MONDAY NIGHT BEFORE MOVING THROUGH THE AREA TUESDAY. S TO SE WINDS OF 10 TO 15 KT MONDAY WILL INCREASE TO 15 TO 20 KT MONDAY NIGHT. SPEEDS WILL RAMP UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY NIGHT. SEAS OF 3 TO 4 FT MONDAY MORNING WILL BUILD TO 4 TO 6 FT BY TUESDAY MORNING AND PEAK AROUND 7 FT DURING THE DAY TUESDAY. AFTER THE FROPA TUESDAY EVENING...SEAS WILL FURTHER BUILD TUESDAY NIGHT...PERHAPS REACHING 8 OR 9 FT AT 20 NM BY DAYBREAK TUESDAY. DUE TO UNCERTAINTIES IN THE EXACT TIMING...WILL NOT ISSUE A 4TH PERIOD SMALL CRAFT ADVISORY BUT ONE WILL BE REQUIRED AT SOME POINT TUESDAY AND A GALE WARNING MAY BE REQUIRED FOR TUESDAY NIGHT. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...A PROLONGED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS IS EXPECTED. GUSTS TO GALE FORCE ARE POSSIBLE INTO WED. THE TIGHTEST PRESSURE GRADIENT IS EXPECTED TO DEVELOP IN THE WAKE OF A STRONG COLD FRONT AS STRONG HIGH PRESSURE NOSES INTO THE CAROLINAS AND THEN EVOLVES INTO A PERSISTENT WEDGE OF HIGH PRESSURE WED AND THU. THE STRONGEST WINDS ARE EXPECTED INTO WED AND IT IS DURING THIS TIME THAT GUSTS TO GALE FORCE ARE MOST PROBABLE. SUSTAINED WIND SPEEDS MAY BRIEFLY REACH GALE CRITERIA DURING THIS TIME. ONCE THE VERY TIGHT PRESSURE GRADIENT DEVELOPS...IT IS EXPECTED TO PERSIST. THEREFORE...WIND SPEEDS ARE EXPECTED TO REMAIN ABOVE SMALL CRAFT ADVISORY THRESHOLDS INTO THU NIGHT OR FRI. THE WIND DIRECTION WILL BE NE...VEERING TO A MORE EASTERLY DIRECTION AS A COASTAL TROUGH BECOMES MORE PRONOUNCED ON FRI. SEAS WILL BE HIGHEST WED...7 TO 9 FT AND UP TO 10 FT NEAR FRYING PAN SHOALS BUOY AS A DRY AND CHILLY NE SURGE ENVELOPS THE WATERS. SEAS WILL LIKELY NOT FALL BELOW 6 FT ACROSS THE OUTER WATERS UNTIL FRI. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...JDW SHORT TERM...31 LONG TERM...RJD AVIATION...43/JDW
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
307 PM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE CONTINUES OFFSHORE THROUGH TONIGHT. A COLD FRONT WILL APPROACH FROM THE WEST LATE MONDAY AND SLOWLY CROSS THE REGION TUESDAY NIGHT. LOW PRESSURE WILL LIFT NORTHEAST ALONG THE FRONT WELL OFFSHORE OF THE COAST ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN FROM THE NORTH THURSDAY INTO FRIDAY THEN SLIDE OFFSHORE SATURDAY AS A TROUGH OF LOW PRESSURE DEVELOPS NEAR THE COAST. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AS OF 115 PM SUN...A FEW MINOR TWEAKS WITH THE EARLY AFTERNOON UPDATE. TEMPS HAVE WARMED FASTER THAN EXPECTED AND THUS INCREASED MAX TEMPS A FEW DEGREES TODAY...81-83F INLAND TO MID 70S OBX/SOUTHERN COAST. LASTEST HRRR AND MESOMODELS SUPPORT ISOLATED SHOWERS FOR INLAND COASTAL PLAIN ZONES THIS AFTERNOON DURING PEAK HEATING. SCATTERED TO BROKEN STRATOCUMULUS HAS ALREADY DEVELOPED AND MAY HAVE ENOUGH CONVERGENCE ALONG/AHEAD OF THE SEA-BREEZE TO PRODUCE A SHOWER OR TWO. CLOUDS AND ANY LIGHT SHOWERS WILL DISSIPATE LATE THIS AFTERNOON WITH LOSS OF DAYTIME HEATING. UPPER RIDGE WILL CONTINUE OVER THE SOUTHEAST TODAY WITH SFC HIGH PRESSURE CENTERED OFFSHORE. S/SW FLOW CONTINUES WITH GUSTS AROUND 20 MPH THIS AFTERNOON. LITTLE CHANGE IN THE AIRMASS OVER YESTERDAY WITH PWATS A LITTLE BELOW CLIMO AROUND 2/3" AND WILL SEE MAINLY SUNNY SKIES THIS MORNING AND DIURNALLY DRIVEN CU DEVELOPING FOR THE AFTERNOON WITH A TYPICAL SEABREEZE PATTERN CLEARING CLOUDS FROM THE COAST THROUGH THE AFTERNOON. LOW LEVEL THICKNESSES ONLY SLIGHTLY LOWER THAN YESTERDAY AND EXPECT HIGHS AROUND 10 DEGREES ABOVE NORMAL...IN THE LOWER 80S INLAND TO LOW TO MID 70S ALONG THE IMMEDIATE COAST. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... AS OF 345 AM SUN...THE UPPER RIDGE SLIDES EWD TONIGHT AS AN UPPER TROUGH DIGS INTO THE CENTRAL CONUS BRINGING INCREASING SWLY FLOW ALOFT. SFC HIGH PRES PERSISTS OFFSHORE CONTINUING TO BRING S/SW LOW LEVEL FLOW. MAINLY CLEAR SKIES EXPECTED IN THE EVENING BUT MODEL SOUNDINGS BRING INCREASING MOISTURE BELOW 900MB AS WELL AS INCREASING MOISTURE ALOFT LATE...SO TREND SKIES TO PARTLY CLOUDY AFTER MIDNIGHT...BUT OTHERWISE DRY CONDITIONS EXPECTED. LOW LEVEL MIXING CONTINUES TO BRING MILD OVERNIGHT TEMPS WITH LOWS IN THE UPPER 50S/LOWER 60S. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... AS OF 300 PM SUNDAY...THE UPPER FLOW IS FORECAST TO BECOME MORE AMPLIFIED BY MONDAY NIGHT CONTINUING INTO WEDNESDAY AS A FULL LATITUDE TROUGH MOVES OUT OF THE CENTRAL US INTO EAST WHILE BECOMING NEGATIVELY TILTED BEFORE LIFTING OUT WEDNESDAY. THIS WILL BRING A PERIOD OF UNSETTLED WEATHER TO EASTERN NC MONDAY NIGHT THROUGH TUESDAY NIGHT/POSSIBLY WEDNESDAY MORNING IMMEDIATE COAST. THE PRECIPITATION WILL INITIALLY BE DRIVEN BY WARM ADVECTION AND MAYBE SPEED CONVERGENCE WITH ONSHORE SOUTHERLY FLOW MONDAY NIGHT INTO EARLY TUESDAY. THEN EXPECTING STRONG TO POSSIBLY SEVERE CONVECTION TO DEVELOP LATER TUESDAY AFTERNOON AND EVENING AHEAD OF A STRONG COLD FRONT MOVING INTO THE AREA. CAPE VALUES ARE FORECAST TO REACH 500+ J/KG WITH A 50-60 KT LOW LEVEL JET, LIFTED INDEX VALUES OF -2 TO -4 AND PW VALUES TO 1.75" WHICH IS > +2 SD FROM NORMAL. TORRENTIAL DOWNPOURS, DAMAGING WINDS AND ISOLATED TORNADOES WOULD BE THE MAIN THREATS. CLOUDS AND SHOWERS WILL LIMIT HIGH TEMPS BUT MOST LOCATIONS SHOULD REACH INTO THE 70S ESPECIALLY IF ANY PROLONGED SUNNY BREAKS DEVELOP. WANING CONVECTION WILL BE MOVING OFFSHORE TUESDAY NIGHT WITH A MUCH COOLER AIRMASS BUILDING INTO THE AREA WITH STRONG SFC HIGH PRESSURE TO THE NORTH. LOWS MAY REACH NEAR 40 INLAND EARLY WED AND DEPENDING ON AMOUNT OF CLOUD COVER WHICH PERSISTS IN THE WEDGE SURFACE PATTERN, HIGHS MAY ONLY REACH INTO THE LOW TO MID 50S ON WEDNESDAY IN STRONG POST FRONTAL NORTHERLY FLOW. THESE TEMPERATURES WILL BE 15-20 DEGREES BELOW NORMAL. HIGH PRES WEDGE HOLDS TIGHT WED NIGHT WITH LOWS INLAND POSSIBLY DROPPING INTO THE UPPER 30S DEPENDING ON THE DEGREE OF DECOUPLING. HOWEVER AN ONSHORE FLOW WILL TEND TO KEEP LOWS IN THE UPPER 40 TO NEAR 50 ALONG THE COAST WED NIGHT. DRY WEATHER TO CONTINUE INTO THURSDAY AS THE HIGH STILL INFLUENCES THE WEATHER WHILE TEMPERATURES MODERATE INTO THE MIDDLE 60S WHICH IS STILL AROUND 10 DEGREES BELOW NORMAL. THE FORECAST FOR FRIDAY THROUGH EASTER WEEKEND WILL BE LOW CONFIDENCE AS THERE IS A LOT SPREAD IN THE ENSEMBLES. THE WEDGE PATTERN OF MID WEEK WILL BE BREAKING DOWN AS A TROUGH OF LOW PRESSURE OFFSHORE BEGINS TO DRIFT TOWARD THE COAST WITH POSSIBLE MULTIPLE WEAK AREAS OF LOW PRESSURE FORMING ALONG IT ALONG OR JUST OFF OF THE COAST FRIDAY AND SATURDAY AS A MID LEVEL TROUGH/POSSIBLE CLOSED OFF UPPER LOW MOVE INTO THE AREA. THUS WILL NEED TO CARRY CHANCE POPS THROUGH AT LEAST SATURDAY, ESPECIALLY COASTAL AREAS. DRIER WEATHER COULD BE IN STORE FOR EASTER SUNDAY IF A COLD FRONT MOVES THROUGH THE AREA SATURDAY NIGHT PUSHING THE MOISTURE OFFSHORE. MORE CONFIDENCE IN THE TEMPERATURE FORECAST WITH READINGS MODERATING FROM THE MIDDLE TO PERHAPS UPPER 60S FRIDAY BACK TO CLIMATOLOGICAL NORMS IN THE 70S FOR THE WEEKEND. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... SHORT TERM /THROUGH MONDAY MORNING/... AS OF 120 PM SUN...PREDOMINANTLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD WITH CLEAR TO PARTLY CLOUDY SKIES AS HIGH PRESSURE OFFSHORE CONTINUES TO DOMINATE THE REGION. S/SW FLOW CONTINUES TODAY WITH GUSTS UP TO 20 KT THIS AFTERNOON AND DIURNALLY DRIVEN STRATOCUMULUS OVERSPREADS THE TAF SITES. CANNOT RULE OUT A BRIEF ISOLATED SHOWER OR TWO BUT SHOULD HAVE LITTLE IMPACT ON AVIATION SO WILL NOT INCLUDE IN TAFS AT THIS TIME. MODEL SOUNDINGS SHOWING LOW LEVEL MOISTURE INCREASING THIS EVENING AND COULD SEE SCT CLOUDS AROUND 2K FT DEVELOPING LATE IN THE EVENING AND AFTER MIDNIGHT. LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM SUNDAY...SHOWERS AND SCATTERED TSTMS WILL LEAD TO PERIODS OF REDUCED FLIGHT CATEGORIES AND GUSTY SW WINDS MONDAY NIGHT AND TUESDAY AS A STRONG COLD FRONT CROSSES THE AREA. THE PRECIPITATION IS FORECAST TO MOVE OUT OF THE REGION LATE TUESDAY NIGHT OR EARLY WEDNESDAY WITH CLEARING SKIES AND PREDOMINANT VFR RETURNING WEDNESDAY AND CONTINUING THROUGH THURSDAY AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. SHOWERS AND POSSIBLE SUB VFR CONDITIONS COULD RETURN FRIDAY AS MOISTURE ASSOCIATED WITH A COASTAL TROUGH MOVES INTO THE AREA. && .MARINE... SHORT TERM /THROUGH MONDAY/... AS OF 120 PM SUN...LATEST SURFACE AND BUOY DATA INDICATES SOUTHERLY WINDS 5-10 KT ACROSS THE WATERS WITH SEAS 1-3 FT. HIGH PRESSURE WILL PERSIST OFFSHORE THROUGH THE SHORT TERM BRINGING S/SSW FLOW. WINDS GENERALLY 10 KT OR LESS THIS MORNING BUT SOME TIGHTENING OF THE GRADIENT THIS AFTERNOON INCREASES WINDS TO 10-15 KT THROUGH TONIGHT. WAVES AROUND 2 FT BUILD TO 3-4 FT THIS AFTERNOON INTO TONIGHT. LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM SUNDAY...MARINERS CAN EXPECT ROUGH CONDITIONS FOR MUCH OF THE WEEK ACROSS THE EASTERN NC WATERS. INCREASING SSW FLOW AHEAD OF A COLD FRONT WILL LEAD TO A PERIOD OF STRONG SMALL CRAFT CONDITIONS MONDAY NIGHT THROUGH TUESDAY. THE COLD FRONT PASSES THROUGH THE MARINE AREA TUESDAY NIGHT WITH STRONG POST FRONTAL NORTHERLY WINDS POSSIBLY REACHING GALE FORCE AT TIMES TUESDAY NIGHT INTO WEDNESDAY IN AN INLAND WEDGE/OFFSHORE FRONT SURFACE PRESSURE PATTERN. WINDS SHIFT MORE NE BUT ONLY VERY SLOWLY DECREASE THURSDAY WHICH WILL MAINTAIN SMALL CRAFT ADVISORY THRESHOLDS FOR ELEVATED SEAS THROUGH FRIDAY. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...NONE. && $$ SYNOPSIS...DAG NEAR TERM...DAG SHORT TERM...DAG LONG TERM...BTC/JME AVIATION...DAG MARINE...JME/DAG
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
122 PM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE CONTINUES OFFSHORE THROUGH TONIGHT. A COLD FRONT WILL APPROACH FROM THE WEST LATE MONDAY AND SLOWLY CROSS THE REGION TUESDAY. LOW PRESSURE WILL LIFT NORTHEAST ALONG THE FRONT WELL OFFSHORE OF THE COAST ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN FROM THE NORTH THURSDAY INTO FRIDAY THEN SLIDE OFFSHORE SATURDAY AS A TROUGH OF LOW PRESSURE DEVELOPS NEAR THE COAST. && .NEAR TERM /THIS AFTERNOON/... AS OF 115 PM SUN...A FEW MINOR TWEAKS WITH THE EARLY AFTERNOON UPDATE. TEMPS HAVE WARMED FASTER THAN EXPECTED AND THUS INCREASED MAX TEMPS A FEW DEGREES TODAY...81-83F INLAND TO MID 70S OBX/SOUTHERN COAST. LASTEST HRRR AND MESOMODELS SUPPORT ISOLATED SHOWERS FOR INLAND COASTAL PLAIN ZONES THIS AFTERNOON DURING PEAK HEATING. SCATTERED TO BROKEN STRATOCUMULUS HAS ALREADY DEVELOPED AND MAY HAVE ENOUGH CONVERGENCE ALONG/AHEAD OF THE SEA-BREEZE TO PRODUCE A SHOWER OR TWO. CLOUDS AND ANY LIGHT SHOWERS WILL DISSIPATE LATE THIS AFTERNOON WITH LOSS OF DAYTIME HEATING. UPPER RIDGE WILL CONTINUE OVER THE SOUTHEAST TODAY WITH SFC HIGH PRESSURE CENTERED OFFSHORE. S/SW FLOW CONTINUES WITH GUSTS AROUND 20 MPH THIS AFTERNOON. LITTLE CHANGE IN THE AIRMASS OVER YESTERDAY WITH PWATS A LITTLE BELOW CLIMO AROUND 2/3" AND WILL SEE MAINLY SUNNY SKIES THIS MORNING AND DIURNALLY DRIVEN CU DEVELOPING FOR THE AFTERNOON WITH A TYPICAL SEABREEZE PATTERN CLEARING CLOUDS FROM THE COAST THROUGH THE AFTERNOON. LOW LEVEL THICKNESSES ONLY SLIGHTLY LOWER THAN YESTERDAY AND EXPECT HIGHS AROUND 10 DEGREES ABOVE NORMAL...IN THE LOWER 80S INLAND TO LOW TO MID 70S ALONG THE IMMEDIATE COAST. && .SHORT TERM /TONIGHT/... AS OF 345 AM SUN...THE UPPER RIDGE SLIDES EWD TONIGHT AS AN UPPER TROUGH DIGS INTO THE CENTRAL CONUS BRINGING INCREASING SWLY FLOW ALOFT. SFC HIGH PRES PERSISTS OFFSHORE CONTINUING TO BRING S/SW LOW LEVEL FLOW. MAINLY CLEAR SKIES EXPECTED IN THE EVENING BUT MODEL SOUNDINGS BRING INCREASING MOISTURE BELOW 900MB AS WELL AS INCREASING MOISTURE ALOFT LATE...SO TREND SKIES TO PARTLY CLOUDY AFTER MIDNIGHT...BUT OTHERWISE DRY CONDITIONS EXPECTED. LOW LEVEL MIXING CONTINUES TO BRING MILD OVERNIGHT TEMPS WITH LOWS IN THE UPPER 50S/LOWER 60S. && .LONG TERM /MONDAY THROUGH SATURDAY/... FLOW BECOMES MORE AMPLIFIED EARLY THIS FORECAST PERIOD WITH FULL LATITUDE TROF DIGGING THRU THE CENTRAL US. THIS WILL BRING ABOUT AN INCREASINGLY UNSETTLED PERIOD OF WEATHER EARLY NEXT WEEK. UPPER FLOW BACKS TO THE SW WITH SFC HIGH OFFSHORE PROVIDING A DEEPENING MOIST SW FLOW MONDAY. A LEAD SHORT WAVE IN THE SW FLOW ALOFT BRINGS INCREASING CHANCES FOR SHOWERS AND POSSIBLE TSTMS MONDAY AFTERNOON AND MONDAY NIGHT. SHUD SEE PLENTY OF SUN EARLY MONDAY ALLOWING TEMPS TO REACH AROUND 80 DEGREES INLAND (AROUND 70 BEACHES) ON THE MILD SW FLOW BEFORE AFTERNOON INCREASING CLOUDS AND SCATTERED SHOWERS MOVE IN. THE MILD SW FLOW CONTINUES MONDAY NIGHT WITH LOWS ONLY IN THE LOW TO MID 60S DESPITE A GOOD CHANCE OF SHOWERS OVERNIGHT. TUESDAY LOOKING TO BE CONVECTIVELY ACTIVE WITH A SHARP UPPER TROF AND SFC COLD FRONT POISED TO CROSS THE AREA DURING THE LATE AFTN AND EVENING. CAPE VALUES 500+ J/KG AND 50-60KT LOW LEVEL JET WILL SUPPORT STRONG TO POSSIBLY SEVERE THUNDERSTORMS AND WILL MENTION THE THREAT IN UPDATED HWO THIS MORNING. CLOUDS AND SHOWERS MAY PUT A LID ON HIGH TEMPS BUT MOST AREAS SHUD REACH INTO THE 70S ESPECIALLY IF ANY PROLONGED SUNNY BREAKS DEVELOP ON TUESDAY. WANING CONVECTION MOVES OFFSHORE TUESDAY NIGHT WITH A MUCH COOLER AIRMASS BUILDING INTO THE AREA WITH STRONG SFC HIGH PRESSURE TO THE NORTH. LOWS MAY REACH NEAR 40 INLAND EARLY WED AND DESPITE PLENTY OF SUNSHINE HIGHS MAY ONLY REACH INTO THE LOW TO MID 50S ON WEDNESDAY WHICH IS 15-20 DEGS BLO NORMAL. HIGH PRES WEDGE HOLDS TIGHT WED NIGHT WITH LOWS INLAND POSSIBLY DROPPING INTO THE UPPER 30S. HOWEVER AN ONSHORE FLOW WILL KEEP LOWS IN THE UPPER 40 TO NEAR 50 ALONG THE COAST WED NIGHT. HIGH PRESSURE WEDGE WILL GRADUALLY BREAK DOWN LATE IN THE WEEK AS AN OFFSHORE TROF OF LOW PRESSURE BACKS UP TOWARD THE SE COAST. TEMPERATURES WILL MODERATE THRU THE END OF THE WEEK WITH HIGHS SURGING BACK INTO THE 60S THU/FRI. PRECIP CHANCES WILL ALSO BE GRADUALLY INCREASING DURING THE LATE WEEK AND INTO EARLY NEXT WEEKEND COURTESY OF THE INLAND MOVING COASTAL TROF AND APPROACHING MID LEVEL TROF. TEMPERATURES WILL AGAIN BE NEAR CLIMATOLOGICAL NORMS AHEAD OF NEXT COLD FRONT FRI NIGHT INTO SAT. && .AVIATION /17Z SUNDAY THROUGH THURSDAY/... SHORT TERM /THROUGH MONDAY MORNING/... AS OF 120 PM SUN...PREDOMINANTLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD WITH CLEAR TO PARTLY CLOUDY SKIES AS HIGH PRESSURE OFFSHORE CONTINUES TO DOMINATE THE REGION. S/SW FLOW CONTINUES TODAY WITH GUSTS UP TO 20 KT THIS AFTERNOON AND DIURNALLY DRIVEN STRATOCUMULUS OVERSPREADS THE TAF SITES. CANNOT RULE OUT A BRIEF ISOLATED SHOWER OR TWO BUT SHOULD HAVE LITTLE IMPACT ON AVIATION SO WILL NOT INCLUDE IN TAFS AT THIS TIME. MODEL SOUNDINGS SHOWING LOW LEVEL MOISTURE INCREASING THIS EVENING AND COULD SEE SCT CLOUDS AROUND 2K FT DEVELOPING LATE IN THE EVENING AND AFTER MIDNIGHT. LONG TERM /MONDAY THROUGH THURSDAY/... MAINLY VFR EXPECTED ON MONDAY BEFORE INCREASING CHANCES OF SHOWERS AND SCATTERED TSTMS LEAD TO PERIODS OF REDUCED FLIGHT CATEGORIES AND GUSTY SW WINDS MONDAY NIGHT AND TUESDAY. PRECIPITATION MOVES OUT TUESDAY EVENING WITH CLEARING SKIES AND PREDOMINANT VFR RETURNING TUESDAY NIGHT AND LIKELY CONTINUING THRU THURSDAY AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. && .MARINE... SHORT TERM /THROUGH TONIGHT/... AS OF 120 PM SUN...LATEST SURFACE AND BUOY DATA INDICATES SOUTHERLY WINDS 5-10 KT ACROSS THE WATERS WITH SEAS 1-3 FT. HIGH PRESSURE WILL PERSIST OFFSHORE THROUGH THE SHORT TERM BRINGING S/SSW FLOW. WINDS GENERALLY 10 KT OR LESS THIS MORNING BUT SOME TIGHTENING OF THE GRADIENT THIS AFTERNOON INCREASES WINDS TO 10-15 KT THROUGH TONIGHT. WAVES AROUND 2 FT BUILD TO 3-4 FT THIS AFTERNOON INTO TONIGHT. LONG TERM /MONDAY THROUGH THURSDAY/... INCREASING SSW FLOW AHEAD OF A COLD FRONT WILL LEAD TO A PERIOD OF SMALL CRAFT CONDITIONS MONDAY NIGHT THRU TUESDAY. THE COLD FRONT PASSES THRU THE MARINE AREA TUESDAY NIGHT WITH STRONG POST FRONTAL NORTHERLY WINDS POSSIBLY NEARING GALE FORCE AT TIMES LATE TUESDAY NIGHT AND WEDNESDAY. WINDS SHIFT MORE NE BUT ONLY VERY SLOWLY DECREASING THRU THURSDAY WHICH WILL LIKELY MAINTAIN SMALL CRAFT ADVISORY THRESHOLDS THRU THE END OF THE FORECAST PERIOD. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...NONE. && $$ SYNOPSIS...SK NEAR TERM...SK/DAG SHORT TERM...SK LONG TERM...BTC AVIATION...BTC/SK/DAG MARINE...BTC/SK/DAG
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1005 AM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO SATURDAY...BRINGING COOL TEMPERATURES FOR MIDWEEK FOLLOWED BY MODERATING TEMPERATURES INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM SUNDAY...ANOTHER BEAUTIFUL MID-SPRING DAY ACROSS THE CAROLINAS TODAY AS HIGH PRESSURE CONTINUES ITS INFLUENCE OVER THE REGION. ALTHOUGH THE CENTER OF THIS HIGH IS WELL OFF THE MID-ATLANTIC COAST...IT CONTINUES TO RIDGE BACK TOWARDS THE SOUTHEAST...WITH WARM S/SW RETURN FLOW FLOODING INTO THE LOCAL AREA. AT THE SAME TIME...MID LEVEL RIDGING HAS EXPANDED OVERHEAD...FORCING SUBSIDENCE AND VERY DRY AIR ABOVE 800MB. THIS IS CLEARLY EVIDENT ON 12Z KCHS SOUNDING WITH MOISTURE ONLY PRESENT ABOVE 300MB...AND NOTED LOCALLY BY WIDESPREAD AIRCRAFT CONTRAILS PERSISTING OUTSIDE THE ILM WFO THIS MORNING. TEMPS HAVE SOARED ABOVE ANY OF THE FORECAST CURVES THUS FAR...AND HAVE BUMPED INHERITED HIGH TEMPS A DEGREE OR TWO ACROSS THE AREA...WITH WIDESPREAD 80+ EXPECTED TODAY...MID 70S AT THE BEACHES. HRRR ONCE AGAIN SUGGESTS SOME ISOLATED SEA BREEZE SHOWERS WILL BE POSSIBLE THIS AFTN...AND HAVE CARRIED A TOKEN 5% POP ALONG THIS BOUNDARY. HOWEVER...EXPECT IT IS ONCE AGAIN OVERDOING PRECIP...ESPECIALLY NOTING HOW DRY SOUNDINGS ARE AND HOW SIGNIFICANT THE SUBSIDENCE INVERSION IS THIS MORNING. DO EXPECT DIURNAL CU TO BECOME MODERATE AND WIDESPREAD LATER TODAY...BUT NO PRECIP IS ANTICIPATED. LOWS TONIGHT WILL REMAIN QUITE WARM AS SOUTHERLY FLOW INCREASES ON A SLOWLY TIGHTENING PRESSURE GRADIENT. THIS SHOULD PRECLUDE MUCH FOG OVERNIGHT...ALTHOUGH PATCHY FOG WILL BE POSSIBLE. LOWS WILL DROP TO A DEGREE OR TWO EITHER SIDE OF 60 BY MONDAY MORNING. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 AM SUNDAY...A COLD FRONT WILL BE NEARING THE CAROLINAS ON MONDAY AS HIGH PRESSURE SLIPS FURTHER OFF SHORE. AS THE MID TO UPPER TROUGH SHIFTS EAST THROUGH THE DAY A DEEP S TO SW FLO WILL DEVELOP. WILL BASICALLY SEE AN INCREASINGLY MOIST AND WARM ENVIRONMENT AS WE TAP INTO BOTH ATLANTIC AND GULF MOISTURE. PCP WATER VALUES WILL INCREASE CLOSE TO 1.5 INCHES BY MON EVENING. THE MID LEVELS WILL REMAIN FAIRLY DRY INITIALLY WITH MOISTURE PROFILES AND SOUNDINGS SHOWING GREATER RH LEVELS CONFINED TO THE UPPER LEVELS AND BELOW H50...BUT BY MON EVENING INTO TUES INCREASING WINDS WILL PROVIDE DEEPENING MOISTURE THROUGH THE COLUMN. THEREFORE EXPECT CLOUDS TO INCREASE THROUGH LATE MONDAY WITH INCREASING CHC OF PCP MON NIGHT INTO TUES AHEAD OF COLD FRONT. WILL INCLUDE A CHC OF LOCALIZED CONVECTION MAINLY ASSOCIATED WITH CONVERGENCE ALONG SEA BREEZE. ALTHOUGH CLOUDS WILL INCREASE DURING THE DAY ON MONDAY...TEMPS WILL SOAR WELL INTO THE 70S AND WITH CLOUDS IN THE FORECAST FOR MON NIGHT...EXPECT ABOVE NORMAL TEMPS IN THE 60S. UPPER TROUGH WILL PUSH COLD FRONT THROUGH THE CAROLINAS MON NIGHT INTO TUES. AS LOW LEVEL FLOW INCREASES AHEAD OF THE FRONT THERE WILL BE INCREASING MOISTURE AND LIFT TO PROVIDE FOR CHC OF SHOWERS AND THUNDERSTORMS. MAY SEE MORE IN THE WAY OF SPEED CONVERGENCE GENERATING COASTAL SHOWERS FEEDING ON SHORE WITH INCREASING SOUTHERLY FLOW WITH MORE NUMEROUS SHOWER AND THUNDERSTORMS ALONG AND AHEAD OF COLD FRONT WHERE BETTER UPPER LEVEL SUPPORT WILL BE THROUGH TUESDAY. PCP WATER VALUES WILL INCREASE UP AROUND 1.75 INCHES BY NOON ON TUES A LLJ INCREASES UP TO 45 KTS. LOOKS LIKE THE THE BEST ACTIVITY WILL COME THROUGH TUES AFTN INTO THE EVENING ALONG AND JUST AHEAD OF COLD FRONT WHERE GREATEST LIFT AND MOISTURE WILL BE. EXPECT MAIN THREAT TO BE HEAVY RAIN AND SOME ISOLATED STRONGER DAMAGING WINDS. SPC INCLUDED CAROLINAS IN SLIGHT RISK FOR TUES WITH WITH POTENTIAL FOR DAMAGING WINDS BUT MENTION OF TORNADOES POSSIBLE. ALTHOUGH CLOUDS AND PCP WILL BE IN THE FORECAST FOR TUES...TEMPS WILL REACH CLOSER TO 80 WITH PLENTY OF WAA AHEAD OF FRONT. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 300 AM SUNDAY...COOL HIGH PRESSURE WILL BUILD IN BEHIND COLD FRONT ON WEDNESDAY. LOW LEVEL THICKNESSES AND 850 TEMPS PLUMMET FROM AROUND 14 C DOWN CLOSE TO 6C IN COOL NORTHERLY WINDS. TEMPS MAY BE TRICKY ON WED. ENOUGH DRY AIR AND SUBSIDENCE SHOULD BE PRESENT TO OFFSET THIS CAA AND THEREFORE EXPECT ENOUGH SUNSHINE TO OFFSET SOME OF THE CAA. THEREFORE DEPENDING ON QUICKLY WE CLEAR AND HOW MUCH SUN WE GET...COULD MAKE A MAJOR DIFFERENCE IN THE WED AFTN TEMPS. FOR NOW WILL GO WITH AN ALMOST 20 DEGREE DROP FROM PREVIOUS DAY WITH MAX TEMPS CLOSER TO 60. HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THROUGH THE CAROLINAS THROUGH THURS INTO FRI WHILE THE BOUNDARY TO THE SOUTH BEGINS TO RETURN NORTH AS A WARM FRONT. LOOKS LIKE A WEDGE TYPE PATTERN DEVELOPS WITH WARM FRONT/COASTAL TROUGH SHIFTING NORTH. FOR NOW IT LOOKS LIKE WE MAY SQUEEZE OUT SOME DECENT WEATHER THROUGH WED INTO THURS WITH INCREASING LIFT WITH CLOUDS AND PCP MOVING UP FROM THE SOUTH BY FRI. AT THE SAME TIME A LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT THROUGH THE AREA FRI NIGHT INTO EARLY SAT. OVERALL THINK GREATER CHC OF CLOUDS AND PCP WILL ENTER INTO THE FORECAST BY LATE THURS THROUGH FRI WITH TEMPS RUNNING BELOW NORMAL BUT WARMING EACH DAY HEADING INTO THE WEEKEND. DRY HIGH PRESSURE WILL BUILD BACK IN THROUGH THE WEEKEND WITH WARMING TEMPS. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 12Z...PATCHES OF DENSE FOG INLAND WILL MIX OUT SOMETIME BETWEEN 13-14Z AS THE INVERSION BREAKS. THE RUC HAS ABOUT 1000 CAPE BY MIDDAY...BUT LITTLE MOISTURE TO WORK WITH. THE HRRR KICKS OFF A COUPLE OF SHOWERS BY 16Z...BUT THINK IT WILL BE SPRINKLE AT MOST. MORE THAN LIKELY JUST MODERATE CU. SOUTHERLY WINDS AT ALL TERMINALS TODAY...PICKING UP BY LATE MORNING WITH THE BEST MIXING CONDITIONS. LIGHT WINDS TONIGHT...BUT THEY MAY STAY UP ENOUGH TO PRECLUDE ANY FOG. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS LATE MONDAY THROUGH TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM SUNDAY...VERY CALM ACROSS THE COASTAL WATERS THIS MORNING...WITH FRYING PAN SHOALS ACTUALLY REPORTING 0 KTS OF WIND WITH THE LAST OBSERVATION. HIGH PRESSURE EXTENDING BACK TOWARDS THE COAST IS RESPONSIBLE FOR THE WEAK GRADIENT AND CALM CONDITIONS...AND ALTHOUGH S/SE WINDS WILL INCREASE TO AROUND 10 KTS LATER TODAY...OVERALL MARINE CONDITIONS WILL REMAIN TRANQUIL THROUGH THE PERIOD. SEAS OF 1-2 FT CURRENTLY WILL RISE TO 2-3 FT BY THE END OF THE PERIOD...WITH A LOW AMPLITUDE SE GROUND SWELL AND SE WIND WAVE COMPRISING THE SPECTRUM. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 AM SUNDAY...COLD FRONT WILL APPROACH THE CAROLINAS AS HIGH PRESSURE SLIPS FARTHER OFF SHORE THROUGH MONDAY. EXPECT GRADIENT TO TIGHTEN THROUGH THE DAY WITH INCREASING SOUTHERLY RETURN FLOW WITH S-SE WINDS UP TO 15 KTS BY AFTN AND UP TO 15 TO 20 KTS BY MON NIGHT. THIS PERSISTENT SOUTHERLY FLOW WILL PUSH SEAS UP INTO SCA THRESHOLDS BY MON EVENING AHEAD OF COLD FRONT BUT WILL CONTINUE TO TO INCREASE AS WINDS INCREASE UP TO 25 KTS THROUGH TUES. WNA SHOWS SEAS PEAKING AROUND 6 TO 8 FT TUES EVENING BUT WILL REMAIN HIGH IN NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT INTO WED. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 300 AM SUNDAY...A PROLONGED PERIOD OF SCA CONDITIONS WILL LAST AS GRADIENT REMAINS PINCHED IN WEDGE/COASTAL TROUGH PATTERN THROUGH WED INTO THURS AS HIGH PRESSURE BUILDS IN. GALE FORCE WINDS ARE POSSIBLE IN NORTHERLY SURGE BEHIND FRONT THROUGH WED. SEAS WILL BE UP TO 6 TO 8 FT EARLY WED. WINDS WILL BEGIN TO VEER AROUND TO THE NE AND LIGHTEN SLIGHTLY DOWN TO 15 TO 20 KTS BY THURS WITH SEAS DROPPING NEAR OR BELOW SCA THRESHOLDS ON THURS...BUT REMAINING 4 TO 6 FT THROUGH THURS NIGHT INTO EARLY FRI. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...JDW SHORT TERM...RGZ LONG TERM...RGZ AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
710 AM EDT SUN APR 13 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO SATURDAY...BRINGING COOL TEMPERATURES FOR MIDWEEK FOLLOWED BY MODERATING TEMPERATURES INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM SUNDAY...WITH THE LATEST NEAR TERM UPDATE...I HAVE LOWERED MINIMUM TEMPERATURES PER OBSERVATIONS...THE DRY COLUMN AND FADING...FOR THE MOMENT...CIRRUS ARE ALLOWING TEMPERATURES TO DROP A BIT QUICKER THAN ANTICIPATED. ALSO ADDED MORE PATCHY FOG. OTHERWISE...ANOTHER WONDERFUL DAY IS IN STORE FOR THE CWA AS HIGH PRESSURE PREVAILS THROUGH ALL LEVELS OF THE ATMOSPHERE. THE ONLY GAME IN TOWN IS THE MAX/MIN TEMPERATURE FORECAST FOR THE PERIODS. THE GUIDANCE IS VERY CLOSE BUT THE NAM/MET NUMBERS HAVE A SLIGHT EDGE...WARMER AND WENT WITH THESE NUMBERS. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 AM SUNDAY...A COLD FRONT WILL BE NEARING THE CAROLINAS ON MONDAY AS HIGH PRESSURE SLIPS FURTHER OFF SHORE. AS THE MID TO UPPER TROUGH SHIFTS EAST THROUGH THE DAY A DEEP S TO SW FLO WILL DEVELOP. WILL BASICALLY SEE AN INCREASINGLY MOIST AND WARM ENVIRONMENT AS WE TAP INTO BOTH ATLANTIC AND GULF MOISTURE. PCP WATER VALUES WILL INCREASE CLOSE TO 1.5 INCHES BY MON EVENING. THE MID LEVELS WILL REMAIN FAIRLY DRY INITIALLY WITH MOISTURE PROFILES AND SOUNDINGS SHOWING GREATER RH LEVELS CONFINED TO THE UPPER LEVELS AND BELOW H50...BUT BY MON EVENING INTO TUES INCREASING WINDS WILL PROVIDE DEEPENING MOISTURE THROUGH THE COLUMN. THEREFORE EXPECT CLOUDS TO INCREASE THROUGH LATE MONDAY WITH INCREASING CHC OF PCP MON NIGHT INTO TUES AHEAD OF COLD FRONT. WILL INCLUDE A CHC OF LOCALIZED CONVECTION MAINLY ASSOCIATED WITH CONVERGENCE ALONG SEA BREEZE. ALTHOUGH CLOUDS WILL INCREASE DURING THE DAY ON MONDAY...TEMPS WILL SOAR WELL INTO THE 70S AND WITH CLOUDS IN THE FORECAST FOR MON NIGHT...EXPECT ABOVE NORMAL TEMPS IN THE 60S. UPPER TROUGH WILL PUSH COLD FRONT THROUGH THE CAROLINAS MON NIGHT INTO TUES. AS LOW LEVEL FLOW INCREASES AHEAD OF THE FRONT THERE WILL BE INCREASING MOISTURE AND LIFT TO PROVIDE FOR CHC OF SHOWERS AND THUNDERSTORMS. MAY SEE MORE IN THE WAY OF SPEED CONVERGENCE GENERATING COASTAL SHOWERS FEEDING ON SHORE WITH INCREASING SOUTHERLY FLOW WITH MORE NUMEROUS SHOWER AND THUNDERSTORMS ALONG AND AHEAD OF COLD FRONT WHERE BETTER UPPER LEVEL SUPPORT WILL BE THROUGH TUESDAY. PCP WATER VALUES WILL INCREASE UP AROUND 1.75 INCHES BY NOON ON TUES A LLJ INCREASES UP TO 45 KTS. LOOKS LIKE THE THE BEST ACTIVITY WILL COME THROUGH TUES AFTN INTO THE EVENING ALONG AND JUST AHEAD OF COLD FRONT WHERE GREATEST LIFT AND MOISTURE WILL BE. EXPECT MAIN THREAT TO BE HEAVY RAIN AND SOME ISOLATED STRONGER DAMAGING WINDS. SPC INCLUDED CAROLINAS IN SLIGHT RISK FOR TUES WITH WITH POTENTIAL FOR DAMAGING WINDS BUT MENTION OF TORNADOES POSSIBLE. ALTHOUGH CLOUDS AND PCP WILL BE IN THE FORECAST FOR TUES...TEMPS WILL REACH CLOSER TO 80 WITH PLENTY OF WAA AHEAD OF FRONT. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 300 AM SUNDAY...COOL HIGH PRESSURE WILL BUILD IN BEHIND COLD FRONT ON WEDNESDAY. LOW LEVEL THICKNESSES AND 850 TEMPS PLUMMET FROM AROUND 14 C DOWN CLOSE TO 6C IN COOL NORTHERLY WINDS. TEMPS MAY BE TRICKY ON WED. ENOUGH DRY AIR AND SUBSIDENCE SHOULD BE PRESENT TO OFFSET THIS CAA AND THEREFORE EXPECT ENOUGH SUNSHINE TO OFFSET SOME OF THE CAA. THEREFORE DEPENDING ON QUICKLY WE CLEAR AND HOW MUCH SUN WE GET...COULD MAKE A MAJOR DIFFERENCE IN THE WED AFTN TEMPS. FOR NOW WILL GO WITH AN ALMOST 20 DEGREE DROP FROM PREVIOUS DAY WITH MAX TEMPS CLOSER TO 60. HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THROUGH THE CAROLINAS THROUGH THURS INTO FRI WHILE THE BOUNDARY TO THE SOUTH BEGINS TO RETURN NORTH AS A WARM FRONT. LOOKS LIKE A WEDGE TYPE PATTERN DEVELOPS WITH WARM FRONT/COASTAL TROUGH SHIFTING NORTH. FOR NOW IT LOOKS LIKE WE MAY SQUEEZE OUT SOME DECENT WEATHER THROUGH WED INTO THURS WITH INCREASING LIFT WITH CLOUDS AND PCP MOVING UP FROM THE SOUTH BY FRI. AT THE SAME TIME A LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT THROUGH THE AREA FRI NIGHT INTO EARLY SAT. OVERALL THINK GREATER CHC OF CLOUDS AND PCP WILL ENTER INTO THE FORECAST BY LATE THURS THROUGH FRI WITH TEMPS RUNNING BELOW NORMAL BUT WARMING EACH DAY HEADING INTO THE WEEKEND. DRY HIGH PRESSURE WILL BUILD BACK IN THROUGH THE WEEKEND WITH WARMING TEMPS. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 12Z...PATCHES OF DENSE FOG INLAND WILL MIX OUT SOMETIME BETWEEN 13-14Z AS THE INVERSION BREAKS. THE RUC HAS ABOUT 1000 CAPE BY MIDDAY...BUT LITTLE MOISTURE TO WORK WITH. THE HRRR KICKS OFF A COUPLE OF SHOWERS BY 16Z...BUT THINK IT WILL BE SPRINKLE AT MOST. MORE THAN LIKELY JUST MODERATE CU. SOUTHERLY WINDS AT ALL TERMINALS TODAY...PICKING UP BY LATE MORNING WITH THE BEST MIXING CONDITIONS. LIGHT WINDS TONIGHT...BUT THEY MAY STAY UP ENOUGH TO PRECLUDE ANY FOG. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS LATE MONDAY THROUGH TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM SUNDAY...JUST LIKE THE PUBLIC PART OF THE FORECAST...THE COASTAL WATERS WILL BE TRANQUIL AS WILL. BERMUDA HIGH PRESSURE WILL BE THE MAIN FEATURE PROVIDING SOUTHEAST WINDS OF 10-15 KNOTS...PROBABLY LEANING TOWARD THE LOWER END OF THE RANGE. THE FETCH HAS BEEN IN PLACE A COUPLE OF DAYS NOW BUT THE WAVE SPECTRUM IS STILL PRIMARILY SHORTER PERIOD WIND WAVES. EXPECT MUCH OF THE SAME TODAY AS WE SAW SATURDAY...2-3 FEET. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 AM SUNDAY...COLD FRONT WILL APPROACH THE CAROLINAS AS HIGH PRESSURE SLIPS FARTHER OFF SHORE THROUGH MONDAY. EXPECT GRADIENT TO TIGHTEN THROUGH THE DAY WITH INCREASING SOUTHERLY RETURN FLOW WITH S-SE WINDS UP TO 15 KTS BY AFTN AND UP TO 15 TO 20 KTS BY MON NIGHT. THIS PERSISTENT SOUTHERLY FLOW WILL PUSH SEAS UP INTO SCA THRESHOLDS BY MON EVENING AHEAD OF COLD FRONT BUT WILL CONTINUE TO TO INCREASE AS WINDS INCREASE UP TO 25 KTS THROUGH TUES. WNA SHOWS SEAS PEAKING AROUND 6 TO 8 FT TUES EVENING BUT WILL REMAIN HIGH IN NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT INTO WED. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 300 AM SUNDAY...A PROLONGED PERIOD OF SCA CONDITIONS WILL LAST AS GRADIENT REMAINS PINCHED IN WEDGE/COASTAL TROUGH PATTERN THROUGH WED INTO THURS AS HIGH PRESSURE BUILDS IN. GALE FORCE WINDS ARE POSSIBLE IN NORTHERLY SURGE BEHIND FRONT THROUGH WED. SEAS WILL BE UP TO 6 TO 8 FT EARLY WED. WINDS WILL BEGIN TO VEER AROUND TO THE NE AND LIGHTEN SLIGHTLY DOWN TO 15 TO 20 KTS BY THURS WITH SEAS DROPPING NEAR OR BELOW SCA THRESHOLDS ON THURS...BUT REMAINING 4 TO 6 FT THROUGH THURS NIGHT INTO EARLY FRI. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...SHK SHORT TERM...RGZ LONG TERM...RGZ AVIATION...43
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
145 PM EDT SUN APR 13 2014 .SYNOPSIS... SOUTHERLY FLOW INCREASES THIS AFTERNOON WITH WARM SUMMER LIKE TEMPERATURES. STRONG FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... SENT A QUICK UPDATE TO INCREASE COVERAGE OF LIGHT SHOWERS ACROSS PORTIONS OF SOUTHEAST OHIO DURING THE MORNING HOURS PER LATEST RADAR IMAGES. ALSO INCREASE SKY THERE FOR CONSISTENCY. REST OF FORECAST REMAIN REPRESENTATIVE. PREVIOUS DISCUSSION BELOW... 6 AM UPDATE. WIDELY SCATTERED NOCTURNAL MID LEVEL SHOWERS HAVE FORMED OVER CENTRAL AND SOUTHWESTERN OHIO...ON THE NOSE OF AN 850 MB SOUTHWESTERLY JET. THESE ARE TRACKING NORTHEAST...MAINLY NORTHWEST OF PERRY...VINTON AND MORGAN COUNTIES. WILL INCLUDE JUST A SMALL CHANCE OF A SHOWER THERE EARLY THIS MORNING...BEFORE THEY DISSIPATE SHORTLY AFTER DAWN. OTHERWISE...CLOUDS OVER SOUTHEAST OHIO WILL DECREASE TO JUST MAINLY THIN CIRRUS DURING THE DAY. REMAINDER OF AREA NO CHANGE. PREVIOUS DISCUSSION... HIGH PRESSURE OFF THE EAST COAST WILL STILL BE STRONG ENOUGH TO DOMINATE OUR WEATHER THIS PERIOD...ALTHOUGH CLOUDS INCREASE FROM THE WEST LATE TONIGHT AHEAD OF AN APPROACHING COLD FRONT. THE BIG ISSUE TODAY WILL BE FIRE DANGER. WITH INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND APPROACHING COLD FRONT...SOUTHERLY WINDS WILL BECOME GUSTY UP TO NEAR 30 MPH IN PLACES LATER THIS MORNING AND AFTERNOON. PLENTY OF SUNSHINE AND SOUTHERLY WINDS WILL DRIVE TEMPERATURES WELL INTO 80S THIS AFTERNOON...ABOVE MOST GUIDANCE WITH A RECENT HISTORY OF COLD BIAS. LOW LEVEL MOISTURE WILL BE SLOW TO INCREASE TODAY...SO THAT THE COMBINATION OF THESE FACTORS AND DRYING FUELS PRESENT AN ENHANCED FIRE THREAT. THE RAP MODEL IN THE HI RES SUITE OF MODELS SHOW THIS MOST CLEARLY WITH SOME DRIER AIR MIXING DOWN DURING THE DAY. WE FORECAST RELATIVE HUMIDITIES TO DROP INTO THE 25 TO 30 PERCENT RANGE THIS AFTERNOON...NOT QUITE ENOUGH FOR A RED FLAG WARNING. HOWEVER...ENOUGH CONCERN TO ISSUE A SPECIAL WEATHER STATEMENT FOR AN ENHANCED FIRE THREAT TODAY. WILL MONITOR RELATIVE HUMIDITIES CLOSELY FOR ANY CHANGES. PLENTY OF SUNSHINE TODAY THRU THIN HIGH CLOUDS. FOR TONIGHT...SOUTH WINDS DO SUBSIDE WITH LOSS OF HEATING...WHILE CLOUDS DO INCREASE FROM THE WEST LATER TONIGHT AHEAD OF THE APPROACHING COLD FRONT. HAVE TO GO ABOVE GUIDANCE AGAIN TONIGHT...WITH A SOUTHERLY BREEZE PREVAILING AND CLOUDS INCREASING. LOOK FOR LOWS MOSTLY IN THE 60S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... LOW LEVEL JET AHEAD OF THE COLD FRONT NOW NOT BEING DEPICTED AS STRONG COMPARED TO THE MODEL RUNS LAST NIGHT. NEVERTHELESS...COLD FRONT IS POTENT AND WILL EXPECT A LINE OF CONVECTION CAPABLE OF STRONG WINDS DESPITE THE WEAKENED LOW LEVEL DYNAMICS. INSTABILITY STILL LESS THAN IMPRESSIVE WITH DEWPOINTS IN THE LOW 50S. QUESTIONS ARISE IN THE POPS AHEAD OF THIS EXPECTED LINE ON MONDAY IN THE WARM SECTOR. CANNOT LEAVE POPS OUT...BUT IN EFFORTS TO GET MORE DETERMINISTIC WITH THE TIMING OF CONVECTION CHANCES...HAVE TRIMMED THE FRONT END BY A FEW HOURS AND WAIT UNTIL MID AFTERNOON BEFORE INTRODUCING THE HIGHER POPS. DUE TO THE NORTHWARD TRACK OF THE MAIN CENTER OF LOW PRESSURE WITH THIS FRONTAL SYSTEM...IT WILL TAKE SOME TIME TO CLEAR THE FRONTOGENETIC FORCING OUT OF THE CWA...NECESSITATING THE CHANCES FOR POPS INTO TUESDAY. A VERY COLD AIRMASS FOLLOWS BEHIND THE SYSTEM WITH THICKNESSES DROPPING TO AROUND 520DKM OVER THE NORTHWEST ZONES AND 850MB TEMPERATURES IN THE -10-12C RANGE...DEPENDING ON THE MODEL. REGARDLESS...IT WILL BE COLD...AND WILL LIKELY END UP BELOW FREEZING TUESDAY NIGHT WITH A SURFACE DOME OF HIGH PRESSURE OVER THE MIDDLE OHIO VALLEY. LIKELY WILL HAVE A SHARP DISCREPANCY IN BETWEEN THE HILL TOPS AND THE VALLEYS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... GENERALLY QUIET REST OF THE WORK WEEK WX WISE. CONTINUES TO LOOK LIKE QUITE A CHILLY NIGHT TUESDAY WITH MANY PLACES DIPPING WELL BELOW FREEZING. SOME MODERATION ON WEDNESDAY BUT STILL BELOW NORMAL FOR THIS TIME OF YEAR. THE MORE ROBUST WARM UP OCCURS THURSDAY AND FRIDAY AS UPPER HEIGHTS BUILD AND WAA COMMENCES ON DEVELOPING SW FLOW ALOFT. SOME DIFFERENCES AMONGST THE MODELS BECOME EVIDENT FOR SATURDAY REGARDING INBOUND TROF AND ASSOCIATED COLD FRONT. WILL PLAY IT CLOSE TO WPC AND GO WITH SOME CHANCE POPS AT THIS DISTANCE. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... SATELLITE IMAGES SHOW HIGH LEVEL CIRRUS CROSSING THE AREA. SFC OBSERVATIONS INDICATED THAT THE STRONG SOUTHWEST WINDS ARE MIXING DOWN TO THE SURFACE AS EXPECTED. RADAR VAD WINDS SHOW SOUTHWEST WINDS A LITTLE STRONGER ABOUT 2000 FEET. THIS COULD PRODUCE MOUNTAIN TURBULENCE MAINLY AFFECTING BKW AND EKN THIS AFTERNOON THROUGH TONIGHT. MODELS SHOW INCREASING SOUTHWEST FLOW OVERNIGHT. UNDER WAA AND ISENTROPIC UPGLIDE...THE LOWER ATMOSPHERE COULD DECOUPLE PRODUCING LIGHT VARIABLE WINDS AT THE SURFACE...BUT 20 TO 30 KNOTS WINDS ALOFT. THIS COULD PRODUCE LLWS FOR AREAS THAT DECOUPLE OVERNIGHT. WINDS WILL INCREASE ONCE AGAIN MONDAY WITH DIURNAL MIXING GUSTY UP TO 30 KNOTS ACCOUNTING FOR BUFKIT SOUNDING MOMENTUM TRANSFER. MIXING COULD BE BEST IF A DIURNAL DECK CU DEVELOPS PROVIDING AREAS OF DIFFERENTIAL HEATING. EXPECT STRONG WINDS OVER HIGHER ELEVATIONS. THE INCREASE IN WINDS IS DUE TO THE APPROACHING STRONG COLD FRONT. HOWEVER...THE FRONT AND THE CONVECTION ASSOCIATED WITH IT COULD ENTER SOUTHEAST OH BY THE END OF THE PERIOD OR BY 18Z MONDAY. MVFR/IFR CEILINGS COULD DEVELOP OVER BKW AND OTHER MOUNTAINS VALLEYS UNDER SURFACE SOUTHEAST FLOW. OTHERWISE...WIDESPREAD IFR CONDITIONS EXPECTED THROUGH THE PERIOD, EXCEPT FOR CEILINGS AROUND 8000 FEET AND A BRIEF SHOWER OVER PARTS FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY... FORECAST CONFIDENCE: HIGH. ALTERNATE SCENARIOS: LLWS COULD BE INCLUDED IN TAF LATER IF ATMOSPHERE DECOUPLES...MAINLY AT EKN AND CRW. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z MONDAY... IFR CONDITIONS EXPECTED LATE MONDAY INTO MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...ARJ/JMV SHORT TERM...ARJ/26 LONG TERM...30 AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
747 AM EDT SUN APR 13 2014 .SYNOPSIS... SOUTHERLY FLOW INCREASES SUNDAY WITH WARM SUMMER LIKE TEMPERATURES. STRONG FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... SENT A QUICK UPDATE TO INCREASE COVERAGE OF LIGHT SHOWERS ACROSS PORTIONS OF SOUTHEAST OHIO DURING THE MORNING HOURS PER LATEST RADAR IMAGES. ALSO INCREASE SKY THERE FOR CONSISTENCY. REST OF FORECAST REMAIN REPRESENTATIVE. PREVIOUS DISCUSSION BELOW... 6 AM UPDATE. WIDELY SCATTERED NOCTURNAL MID LEVEL SHOWERS HAVE FORMED OVER CENTRAL AND SOUTHWESTERN OHIO...ON THE NOSE OF AN 850 MB SOUTHWESTERLY JET. THESE ARE TRACKING NORTHEAST...MAINLY NORTHWEST OF PERRY...VINTON AND MORGAN COUNTIES. WILL INCLUDE JUST A SMALL CHANCE OF A SHOWER THERE EARLY THIS MORNING...BEFORE THEY DISSIPATE SHORTLY AFTER DAWN. OTHERWISE...CLOUDS OVER SOUTHEAST OHIO WILL DECREASE TO JUST MAINLY THIN CIRRUS DURING THE DAY. REMAINDER OF AREA NO CHANGE. PREVIOUS DISCUSSION... HIGH PRESSURE OFF THE EAST COAST WILL STILL BE STRONG ENOUGH TO DOMINATE OUR WEATHER THIS PERIOD...ALTHOUGH CLOUDS INCREASE FROM THE WEST LATE TONIGHT AHEAD OF AN APPROACHING COLD FRONT. THE BIG ISSUE TODAY WILL BE FIRE DANGER. WITH INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND APPROACHING COLD FRONT...SOUTHERLY WINDS WILL BECOME GUSTY UP TO NEAR 30 MPH IN PLACES LATER THIS MORNING AND AFTERNOON. PLENTY OF SUNSHINE AND SOUTHERLY WINDS WILL DRIVE TEMPERATURES WELL INTO 80S THIS AFTERNOON...ABOVE MOST GUIDANCE WITH A RECENT HISTORY OF COLD BIAS. LOW LEVEL MOISTURE WILL BE SLOW TO INCREASE TODAY...SO THAT THE COMBINATION OF THESE FACTORS AND DRYING FUELS PRESENT AN ENHANCED FIRE THREAT. THE RAP MODEL IN THE HI RES SUITE OF MODELS SHOW THIS MOST CLEARLY WITH SOME DRIER AIR MIXING DOWN DURING THE DAY. WE FORECAST RELATIVE HUMIDITIES TO DROP INTO THE 25 TO 30 PERCENT RANGE THIS AFTERNOON...NOT QUITE ENOUGH FOR A RED FLAG WARNING. HOWEVER...ENOUGH CONCERN TO ISSUE A SPECIAL WEATHER STATEMENT FOR AN ENHANCED FIRE THREAT TODAY. WILL MONITOR RELATIVE HUMIDITIES CLOSELY FOR ANY CHANGES. PLENTY OF SUNSHINE TODAY THRU THIN HIGH CLOUDS. FOR TONIGHT...SOUTH WINDS DO SUBSIDE WITH LOSS OF HEATING...WHILE CLOUDS DO INCREASE FROM THE WEST LATER TONIGHT AHEAD OF THE APPROACHING COLD FRONT. HAVE TO GO ABOVE GUIDANCE AGAIN TONIGHT...WITH A SOUTHERLY BREEZE PREVAILING AND CLOUDS INCREASING. LOOK FOR LOWS MOSTLY IN THE 60S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... LOW LEVEL JET AHEAD OF THE COLD FRONT NOW NOT BEING DEPICTED AS STRONG COMPARED TO THE MODEL RUNS LAST NIGHT. NEVERTHELESS...COLD FRONT IS POTENT AND WILL EXPECT A LINE OF CONVECTION CAPABLE OF STRONG WINDS DESPITE THE WEAKENED LOW LEVEL DYNAMICS. INSTABILITY STILL LESS THAN IMPRESSIVE WITH DEWPOINTS IN THE LOW 50S. QUESTIONS ARISE IN THE POPS AHEAD OF THIS EXPECTED LINE ON MONDAY IN THE WARM SECTOR. CANNOT LEAVE POPS OUT...BUT IN EFFORTS TO GET MORE DETERMINISTIC WITH THE TIMING OF CONVECTION CHANCES...HAVE TRIMMED THE FRONT END BY A FEW HOURS AND WAIT UNTIL MID AFTERNOON BEFORE INTRODUCING THE HIGHER POPS. DUE TO THE NORTHWARD TRACK OF THE MAIN CENTER OF LOW PRESSURE WITH THIS FRONTAL SYSTEM...IT WILL TAKE SOME TIME TO CLEAR THE FRONTOGENETIC FORCING OUT OF THE CWA...NECESSITATING THE CHANCES FOR POPS INTO TUESDAY. A VERY COLD AIRMASS FOLLOWS BEHIND THE SYSTEM WITH THICKNESSES DROPPING TO AROUND 520DKM OVER THE NORTHWEST ZONES AND 850MB TEMPERATURES IN THE -10-12C RANGE...DEPENDING ON THE MODEL. REGARDLESS...IT WILL BE COLD...AND WILL LIKELY END UP BELOW FREEZING TUESDAY NIGHT WITH A SURFACE DOME OF HIGH PRESSURE OVER THE MIDDLE OHIO VALLEY. LIKELY WILL HAVE A SHARP DISCREPANCY IN BETWEEN THE HILL TOPS AND THE VALLEYS. && .LONG TERM /THURSDAY THROUGH SATURDAY/... GENERALLY QUIET REST OF THE WORK WEEK WX WISE. CONTINUES TO LOOK LIKE QUITE A CHILLY NIGHT TUESDAY WITH MANY PLACES DIPPING WELL BELOW FREEZING. SOME MODERATION ON WEDNESDAY BUT STILL BELOW NORMAL FOR THIS TIME OF YEAR. THE MORE ROBUST WARM UP OCCURS THURSDAY AND FRIDAY AS UPPER HEIGHTS BUILD AND WAA COMMENCES ON DEVELOPING SW FLOW ALOFT. SOME DIFFERENCES AMONGST THE MODELS BECOME EVIDENT FOR SATURDAY REGARDING INBOUND TROF AND ASSOCIATED COLD FRONT. WILL PLAY IT CLOSE TO WPC AND GO WITH SOME CHANCE POPS AT THIS DISTANCE. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... 12Z SUNDAY THRU 12Z MONDAY... COLD FRONT WELL TO THE WEST WILL SLOWLY APPROACH FROM THE WEST...BUT STILL REMAIN WELL WEST OF THE AREA AT 06Z MONDAY. MAIN FEATURE TODAY WILL BE THE SOUTH WINDS GUSTING UP TO 25 TO 30 MPH BY 15Z UPON MIXING THRU HEATING...SUBSIDING SOMEWHAT AROUND 00Z WITH LOSS OF HEATING. EXCEPT FOR CEILINGS AROUND 8000 FEET AND A BRIEF SHOWER OVER PARTS OF SOUTHEAST OHIO THRU 14Z...VFR MOSTLY CLEAR WITH THIN HIGH CLOUDS THRU 06Z WILL DOMINATE THE ENTIRE AREA. CEILINGS AOA 8000 FEET RAPIDLY SPREADING FROM WEST TO EAST THRU 12Z. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY... FORECAST CONFIDENCE: HIGH. ALTERNATE SCENARIOS: NONE. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 12Z MONDAY... IFR CONDITIONS EXPECTED LATE MONDAY INTO MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...JMV/ARJ SHORT TERM...26 LONG TERM...30 AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
614 AM EDT SUN APR 13 2014 .SYNOPSIS... SOUTHERLY FLOW INCREASES SUNDAY WITH WARM SUMMER LIKE TEMPERATURES. STRONG FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... 6 AM UPDATE. WIDELY SCATTERED NOCTURNAL MID LEVEL SHOWERS HAVE FORMED OVER CENTRAL AND SOUTHWESTERN OHIO...ON THE NOSE OF AN 850 MB SOUTHWESTERLY JET. THESE ARE TRACKING NORTHEAST...MAINLY NORTHWEST OF PERRY...VINTON AND MORGAN COUNTIES. WILL INCLUDE JUST A SMALL CHANCE OF A SHOWER THERE EARLY THIS MORNING...BEFORE THEY DISSIPATE SHORTLY AFTER DAWN. OTHERWISE...CLOUDS OVER SOUTHEAST OHIO WILL DECREASE TO JUST MAINLY THIN CIRRUS DURING THE DAY. REMAINDER OF AREA NO CHANGE. PREVIOUS DISCUSSION... HIGH PRESSURE OFF THE EAST COAST WILL STILL BE STRONG ENOUGH TO DOMINATE OUR WEATHER THIS PERIOD...ALTHOUGH CLOUDS INCREASE FROM THE WEST LATE TONIGHT AHEAD OF AN APPROACHING COLD FRONT. THE BIG ISSUE TODAY WILL BE FIRE DANGER. WITH INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND APPROACHING COLD FRONT...SOUTHERLY WINDS WILL BECOME GUSTY UP TO NEAR 30 MPH IN PLACES LATER THIS MORNING AND AFTERNOON. PLENTY OF SUNSHINE AND SOUTHERLY WINDS WILL DRIVE TEMPERATURES WELL INTO 80S THIS AFTERNOON...ABOVE MOST GUIDANCE WITH A RECENT HISTORY OF COLD BIAS. LOW LEVEL MOISTURE WILL BE SLOW TO INCREASE TODAY...SO THAT THE COMBINATION OF THESE FACTORS AND DRYING FUELS PRESENT AN ENHANCED FIRE THREAT. THE RAP MODEL IN THE HI RES SUITE OF MODELS SHOW THIS MOST CLEARLY WITH SOME DRIER AIR MIXING DOWN DURING THE DAY. WE FORECAST RELATIVE HUMIDITIES TO DROP INTO THE 25 TO 30 PERCENT RANGE THIS AFTERNOON...NOT QUITE ENOUGH FOR A RED FLAG WARNING. HOWEVER...ENOUGH CONCERN TO ISSUE A SPECIAL WEATHER STATEMENT FOR AN ENHANCED FIRE THREAT TODAY. WILL MONITOR RELATIVE HUMIDITIES CLOSELY FOR ANY CHANGES. PLENTY OF SUNSHINE TODAY THRU THIN HIGH CLOUDS. FOR TONIGHT...SOUTH WINDS DO SUBSIDE WITH LOSS OF HEATING...WHILE CLOUDS DO INCREASE FROM THE WEST LATER TONIGHT AHEAD OF THE APPROACHING COLD FRONT. HAVE TO GO ABOVE GUIDANCE AGAIN TONIGHT...WITH A SOUTHERLY BREEZE PREVAILING AND CLOUDS INCREASING. LOOK FOR LOWS MOSTLY IN THE 60S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... LOW LEVEL JET AHEAD OF THE COLD FRONT NOW NOT BEING DEPICTED AS STRONG COMPARED TO THE MODEL RUNS LAST NIGHT. NEVERTHELESS...COLD FRONT IS POTENT AND WILL EXPECT A LINE OF CONVECTION CAPABLE OF STRONG WINDS DESPITE THE WEAKENED LOW LEVEL DYNAMICS. INSTABILITY STILL LESS THAN IMPRESSIVE WITH DEWPOINTS IN THE LOW 50S. QUESTIONS ARISE IN THE POPS AHEAD OF THIS EXPECTED LINE ON MONDAY IN THE WARM SECTOR. CANNOT LEAVE POPS OUT...BUT IN EFFORTS TO GET MORE DETERMINISTIC WITH THE TIMING OF CONVECTION CHANCES...HAVE TRIMMED THE FRONT END BY A FEW HOURS AND WAIT UNTIL MID AFTERNOON BEFORE INTRODUCING THE HIGHER POPS. DUE TO THE NORTHWARD TRACK OF THE MAIN CENTER OF LOW PRESSURE WITH THIS FRONTAL SYSTEM...IT WILL TAKE SOME TIME TO CLEAR THE FRONTOGENETIC FORCING OUT OF THE CWA...NECESSITATING THE CHANCES FOR POPS INTO TUESDAY. A VERY COLD AIRMASS FOLLOWS BEHIND THE SYSTEM WITH THICKNESSES DROPPING TO AROUND 520DKM OVER THE NORTHWEST ZONES AND 850MB TEMPERATURES IN THE -10-12C RANGE...DEPENDING ON THE MODEL. REGARDLESS...IT WILL BE COLD...AND WILL LIKELY END UP BELOW FREEZING TUESDAY NIGHT WITH A SURFACE DOME OF HIGH PRESSURE OVER THE MIDDLE OHIO VALLEY. LIKELY WILL HAVE A SHARP DISCREPANCY IN BETWEEN THE HILL TOPS AND THE VALLEYS. && .LONG TERM /THURSDAY THROUGH SATURDAY/... GENERALLY QUIET REST OF THE WORK WEEK WX WISE. CONTINUES TO LOOK LIKE QUITE A CHILLY NIGHT TUESDAY WITH MANY PLACES DIPPING WELL BELOW FREEZING. SOME MODERATION ON WEDNESDAY BUT STILL BELOW NORMAL FOR THIS TIME OF YEAR. THE MORE ROBUST WARM UP OCCURS THURSDAY AND FRIDAY AS UPPER HEIGHTS BUILD AND WAA COMMENCES ON DEVELOPING SW FLOW ALOFT. SOME DIFFERENCES AMONGST THE MODELS BECOME EVIDENT FOR SATURDAY REGARDING INBOUND TROF AND ASSOCIATED COLD FRONT. WILL PLAY IT CLOSE TO WPC AND GO WITH SOME CHANCE POPS AT THIS DISTANCE. && .AVIATION /10Z SUNDAY THROUGH THURSDAY/... 06Z SUNDAY THRU 06Z MONDAY... COLD FRONT WELL TO THE WEST WILL SLOWLY APPROACH FROM THE WEST...BUT STILL REMAIN WELL WEST OF THE AREA AT 06Z MONDAY. MAIN FEATURE TODAY WILL BE THE SOUTH WINDS GUSTING UP TO 25 TO 30 MPH BY 15Z UPON MIXING THRU HEATING...SUBSIDING SOMEWHAT AROUND 00Z WITH LOSS OF HEATING. EXCEPT FOR CEILINGS AROUND 8000 FEET AND A BRIEF SHOWER OVER PARTS OF SOUTHEAST OHIO THRU 14Z...VFR MOSTLY CLEAR WITH THIN HIGH CLOUDS THRU 06Z WILL DOMINATE THE ENTIRE AREA. CEILINGS AOA 8000 FEET RAPIDLY SPREADING FROM WEST TO EAST THRU 12Z. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY... FORECAST CONFIDENCE: HIGH. ALTERNATE SCENARIOS: NONE. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 12Z MONDAY... IFR CONDITIONS EXPECTED LATE MONDAY INTO MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...JMV SHORT TERM...26 LONG TERM...30 AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
401 AM EDT SUN APR 13 2014 .SYNOPSIS... SOUTHERLY FLOW INCREASES SUNDAY WITH WARM SUMMER LIKE TEMPERATURES. STRONG FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... HIGH PRESSURE OFF THE EAST COAST WILL STILL BE STRONG ENOUGH TO DOMINATE OUR WEATHER THIS PERIOD...ALTHOUGH CLOUDS INCREASE FROM THE WEST LATE TONIGHT AHEAD OF AN APPROACHING COLD FRONT. THE BIG ISSUE TODAY WILL BE FIRE DANGER. WITH INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND APPROACHING COLD FRONT...SOUTHERLY WINDS WILL BECOME GUSTY UP TO NEAR 30 MPH IN PLACES LATER THIS MORNING AND AFTERNOON. PLENTY OF SUNSHINE AND SOUTHERLY WINDS WILL DRIVE TEMPERATURES WELL INTO 80S THIS AFTERNOON...ABOVE MOST GUIDANCE WITH A RECENT HISTORY OF COLD BIAS. LOW LEVEL MOISTURE WILL BE SLOW TO INCREASE TODAY...SO THAT THE COMBINATION OF THESE FACTORS AND DRYING FUELS PRESENT AN ENHANCED FIRE THREAT. THE RAP MODEL IN THE HI RES SUITE OF MODELS SHOW THIS MOST CLEARLY WITH SOME DRIER AIR MIXING DOWN DURING THE DAY. WE FORECAST RELATIVE HUMIDITIES TO DROP INTO THE 25 TO 30 PERCENT RANGE THIS AFTERNOON...NOT QUITE ENOUGH FOR A RED FLAG WARNING. HOWEVER...ENOUGH CONCERN TO ISSUE A SPECIAL WEATHER STATEMENT FOR AN ENHANCED FIRE THREAT TODAY. WILL MONITOR RELATIVE HUMIDITIES CLOSELY FOR ANY CHANGES. PLENTY OF SUNSHINE TODAY THRU THIN HIGH CLOUDS. FOR TONIGHT...SOUTH WINDS DO SUBSIDE WITH LOSS OF HEATING...WHILE CLOUDS DO INCREASE FROM THE WEST LATER TONIGHT AHEAD OF THE APPROACHING COLD FRONT. HAVE TO GO ABOVE GUIDANCE AGAIN TONIGHT...WITH A SOUTHERLY BREEZE PREVAILING AND CLOUDS INCREASING. LOOK FOR LOWS MOSTLY IN THE 60S. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... LOW LEVEL JET AHEAD OF THE COLD FRONT NOW NOT BEING DEPICTED AS STRONG COMPARED TO THE MODEL RUNS LAST NIGHT. NEVERTHELESS...COLD FRONT IS POTENT AND WILL EXPECT A LINE OF CONVECTION CAPABLE OF STRONG WINDS DESPITE THE WEAKENED LOW LEVEL DYNAMICS. INSTABILITY STILL LESS THAN IMPRESSIVE WITH DEWPOINTS IN THE LOW 50S. QUESTIONS ARISE IN THE POPS AHEAD OF THIS EXPECTED LINE ON MONDAY IN THE WARM SECTOR. CANNOT LEAVE POPS OUT...BUT IN EFFORTS TO GET MORE DETERMINISTIC WITH THE TIMING OF CONVECTION CHANCES...HAVE TRIMMED THE FRONT END BY A FEW HOURS AND WAIT UNTIL MID AFTERNOON BEFORE INTRODUCING THE HIGHER POPS. DUE TO THE NORTHWARD TRACK OF THE MAIN CENTER OF LOW PRESSURE WITH THIS FRONTAL SYSTEM...IT WILL TAKE SOME TIME TO CLEAR THE FRONTOGENETIC FORCING OUT OF THE CWA...NECESSITATING THE CHANCES FOR POPS INTO TUESDAY. A VERY COLD AIRMASS FOLLOWS BEHIND THE SYSTEM WITH THICKNESSES DROPPING TO AROUND 520DKM OVER THE NORTHWEST ZONES AND 850MB TEMPERATURES IN THE -10-12C RANGE...DEPENDING ON THE MODEL. REGARDLESS...IT WILL BE COLD...AND WILL LIKELY END UP BELOW FREEZING TUESDAY NIGHT WITH A SURFACE DOME OF HIGH PRESSURE OVER THE MIDDLE OHIO VALLEY. LIKELY WILL HAVE A SHARP DISCREPANCY IN BETWEEN THE HILL TOPS AND THE VALLEYS. && .LONG TERM /THURSDAY THROUGH SATURDAY/... GENERALLY QUIET REST OF THE WORK WEEK WX WISE. CONTINUES TO LOOK LIKE QUITE A CHILLY NIGHT TUESDAY WITH MANY PLACES DIPPING WELL BELOW FREEZING. SOME MODERATION ON WEDNESDAY BUT STILL BELOW NORMAL FOR THIS TIME OF YEAR. THE MORE ROBUST WARM UP OCCURS THURSDAY AND FRIDAY AS UPPER HEIGHTS BUILD AND WAA COMMENCES ON DEVELOPING SW FLOW ALOFT. SOME DIFFERENCES AMONGST THE MODELS BECOME EVIDENT FOR SATURDAY REGARDING INBOUND TROF AND ASSOCIATED COLD FRONT. WILL PLAY IT CLOSE TO WPC AND GO WITH SOME CHANCE POPS AT THIS DISTANCE. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... 06Z SUNDAY THRU 06Z MONDAY... COLD FRONT WELL TO THE WEST WILL SLOWLY APPROACH FROM THE WEST...BUT STILL REMAIN WELL WEST OF THE AREA AT 06Z MONDAY. MAIN FEATURE TODAY WILL BE THE SOUTH WINDS GUSTING UP TO 25 TO 30 MPH BY 15Z UPON MIXING THRU HEATING...SUBSIDING SOMEWHAT AROUND 00Z WITH LOSS OF HEATING. VFR MOSTLY CLEAR WITH THIN HIGH CLOUDS THRU 06Z...THEN CEILINGS AOA 8000 FEET RAPIDLY SPREADING FROM WEST TO EAST THRU 12Z. NO PRECIP. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY... FORECAST CONFIDENCE: HIGH. ALTERNATE SCENARIOS: NONE. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE SUN 04/13/14 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 06Z MONDAY... IFR CONDITIONS EXPECTED LATE MONDAY INTO MONDAY NIGHT UNDER MODERATE RAIN SHOWERS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JMV/26 NEAR TERM...JMV SHORT TERM...26 LONG TERM...30 AVIATION...JMV
AREA FORECAST DISCUSSION
NWS TULSA OK
409 PM CDT SUN APR 13 2014 .DISCUSSION... SQUALL LINE DEVELOPING ALONG THE COLD FRONT IS EXPECTED TO CONTINUE TO BUILD SOUTH AND SWEEP ACROSS THE ENTIRE FORECAST AREA LATE THIS AFTERNOON AND THIS EVENING AS SHOWN BY THE LATEST RUNS OF THE HRRR AND LOCAL IN-HOUSE MODELS. THE MAIN SEVERE WEATHER THREAT WILL LIKELY BE TRANSITIONING FROM HAIL TO DAMAGING WINDS OVER TIME...WITH TORNADO PROBABILITIES BEING QUITE LOW DUE TO THE LINEAR NATURE OF THE STORMS. INSTABILITY DECREASES WITH EASTWARD EXTENT DIE TO PERSISTENT CLOUDS/SHOWERS IN SOUTHEAST OKLAHOMA AND WESTERN ARKANSAS SO THERE IS ALSO SOME QUESTION AS TO WHETHER STORMS WILL MAINTAIN THEIR INTENSITY INTO THIS EVENING. MUCH COLDER AIR WILL OVERSPREAD THE AREA BEHIND THE FRONT. SOME LIGHT RAIN WILL BE POSSIBLE MONDAY AHEAD OF A SECONDARY UPPER TROF BUT AMOUNTS WILL BE VERY LIGHT. CLEARING SKIES AND LIGHT WINDS WILL RESULT IN A FREEZE IN ALL AREAS TUESDAY MORNING AND HAVE NOW PLACED THE ENTIRE FORECAST AREA UNDER A FREEZE WARNING. MOST LOCATIONS WILL BE VERY NEAR THE COLDEST TEMPERATURES EVER RECORDED FOR SO LATE IN THE SEASON...WHICH AT TUL/MLC/FYV/FSM ARE THE SAME AS THE RECORD LOWS FOR THE DATE OF APRIL 15TH. TEMPERATURES WILL WARM BACK CLOSER TO NORMAL FOR THE REST OF THE WEEK INTO NEXT WEEKEND...WITH SHOWER AND THUNDERSTORM CHANCES THURSDAY/THURSDAY NIGHT AND AGAIN SATURDAY NIGHT/SUNDAY. STAYED CLOSE TO GUIDANCE TEMPERATURES THE NEXT COUPLE DAYS. && .PRELIMINARY POINT TEMPS/POPS... TUL 38 47 28 61 / 50 30 0 0 FSM 46 50 28 61 / 80 30 10 0 MLC 41 48 29 61 / 60 20 10 0 BVO 36 47 25 61 / 40 30 0 0 FYV 39 43 24 57 / 80 30 10 0 BYV 40 43 25 56 / 80 40 10 0 MKO 40 47 27 60 / 60 30 10 0 MIO 37 44 26 59 / 50 40 10 0 F10 39 47 28 61 / 50 20 10 0 HHW 46 52 30 60 / 70 20 10 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...FREEZE WARNING FROM 1 AM TUESDAY TO 9 AM TUESDAY FOR OKZ049- OKZ053-OKZ054-OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060- OKZ061-OKZ062-OKZ063-OKZ064-OKZ065-OKZ066-OKZ067-OKZ068- OKZ069-OKZ070-OKZ071-OKZ072-OKZ073-OKZ074-OKZ075-OKZ076. AR...FREEZE WARNING FROM 1 AM TUESDAY TO 9 AM TUESDAY FOR ARZ001- ARZ002-ARZ010-ARZ011-ARZ019-ARZ020-ARZ029. && $$ SHORT TERM...02 LONG TERM....05 PLATE
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
415 PM CDT SUN APR 13 2014 .DISCUSSION... .SYNOPSIS... A COUPLE OF UPPER LEVEL SHORTWAVES WILL MOVE THROUGH THE MID-SOUTH THIS EVENING AS A STRONG LOW PRESSURE SYSTEM DEPARTS TO THE NORTHEAST. AS THE LOW MOVES OFF TO THE NORTHEAST...WINDS WILL BECOME MORE BACKED AT THE SURFACE AND A STRONG 50 TO 60 KT MID- LEVEL WESTERLY JET WILL SUPPORT THE CHANCE FOR SOME STRONG TO SEVERE THUNDERSTORMS THROUGH LATE THIS EVENING...MAINLY ALONG AND WEST OF THE MISSISSIPPI RIVER. THE PRIMARY HAZARDS WILL BE DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY MODE IS EXPECTED TO BE A FORCED LINE OF STORMS...ALTHOUGH A TORNADO CANNOT BE RULED OUT. .OVERNIGHT TONIGHT AND INTO TOMORROW AFTERNOON... SUFFICIENT INSTABILITY TO SUPPORT SEVERE THUNDERSTORM DEVELOPMENT WILL BE AVAILABLE OVER A LARGE PART OF THE FORECAST AREA OVERNIGHT AND INTO TOMORROW AFTERNOON...WITH THE BEST INGREDIENTS FOR SEVERE WEATHER SPECIFICALLY OVER NORTH MISSISSIPPI DURING LATE MORNING TO AFTERNOON HOURS ON MONDAY. MODEL GUIDANCE SUGGESTS THAT 1000 TO NEAR 2000 J/KG OF SBCAPE WILL BE ON HAND...ALONG WITH LI/S -6 TO -8C...AND 0-6 KM BULK SHEAR AROUND 60KTS. IN ADDITION...MODELS ARE IN AGREEMENT THAT A DEVELOPING SURFACE LOW WILL TRACK ALONG THE COLD FRONT AND MOVE TO THE NORTHEAST BY TOMORROW EVENING. ALL OF THESE PARAMETERS AND THE LOCATION OF LOW WILL SUPPORT A POTENTIAL FOR DAMAGING WINDS...HAIL...AND PERHAPS A TORNADO. THE LIMITING FACTOR WILL OBVIOUSLY BE CLOUD COVER TOMORROW IN THE WARM SECTOR...AND UNIDIRECTIONAL WIND PROFILES. THE COLD FRONT WILL EXIT THE REGION BY LATE MONDAY NIGHT. BEHIND THE FRONT...VERY COLD AND DRY AIR WILL FUNNEL INTO THE REGION BY TUESDAY MORNING. CURRENT THINKING IS THAT TEMPERATURES WILL DIP INTO THE 30S...BUT THE ATMOSPHERE SHOULD REMAIN MOIST ENOUGH TO FEND OFF ANY FROST FORMING OVERNIGHT ON TUESDAY. FOG WILL MOST LIKELY BE WHAT DEVELOPS INSTEAD. BY TUESDAY...TEMPERATURES WILL STRUGGLE TO CLIMB INTO THE UPPER 50S DURING THE DAY AS STRONG CAA WILL BE PERSISTENT ALL DAY LONG. WINDS WILL DIE DOWN AFTER MIDNIGHT AND TEMPERATURES ARE EXPECTED TO DROP OFF VERY QUICKLY. LOWS WILL BOTTOM OUT IN THE LOWER 30S AND MANY PLACES WILL DIP INTO THE UPPER 20S. A FREEZE WARNING WILL MOST LIKELY BE NEEDED FOR WEDNESDAY MORNING. BY WEDNESDAY HIGH PRESSURE WILL BUILD INTO THE REGION AND TEMPERATURES WILL FINALLY BEGIN TO MODERATE AND A WARMING TREND WILL BEGIN. ANOTHER COLD FRONT IS EXPECTED TO MOVE THROUGH THE MID-SOUTH ON FRIDAY INTO SATURDAY BRINGING RAIN A SLIGHT CHANCE OF THUNDERSTORMS TO THE MID-SOUTH. .THIS WEEKEND... HIGH PRESSURE WILL BRIEFLY BUILD IN ON SATURDAY BEFORE ANOTHER SYSTEM MOVES IN BY LATE SUNDAY. SLIGHT CHANCES FOR RAIN WILL BE POSSIBLE. BY MONDAY...TEMPERATURES ARE EXPECTED TO REBOUND BACK TO SEASONAL TEMPERATURES WITH HIGHS IN THE 70S AND LOWS IN THE 50S. AC3 && .AVIATION... 18Z TAFS MAIN CONCERN REMAINS TIMING OF TSRA ARRIVAL THIS EVENING. FOR THE 18Z TAFS... HAVE MADE ONLY MINOR TIMING ADJUSTMENTS BASED ON 12Z NAM AND 15Z HRRR MODELS. TS CANNOT BE RULED OUT FOR ANY PERIOD BEYOND 03Z...WITH MULTIPLE UPPER LEVEL IMPULSES LIFTING THROUGH AHEAD OF THE MAIN UPPER TROF. HAVE LIMITED TS/VCTS MENTION TO THOSE PERIODS MOST FAVORABLE. SUSPECT THAT THERE WILL BE LULL DURING THE 11Z TO 15Z PERIOD...BUT WITH IFR/MVFR CIGS PREVAILING WITH SCATTERED SHRA. PWB && .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. MO...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1250 PM CDT SUN APR 13 2014 .UPDATE... UPDATED FOR 18Z AVIATION DISCUSSION BELOW. && .PREV DISCUSSION... /ISSUED 946 AM CDT SUN APR 13 2014/ UPDATE... QUICK UPDATE TO INCLUDE THE ISSUANCE OF A WIND ADVISORY FOR NORTHEAST ARKANSAS...THE MISSOURI BOOTHEEL...AND EXTREME NORTHWEST MISSISSIPPI THROUGH THIS EVENING. ELSEWHERE...WINDS WILL BE STRONG 15 TO 25 MPH WITH GUSTS NEAR 30 MPH WHICH IS JUST BELOW CRITERIA. THE REST OF THE FORECAST IS IN GOOD SHAPE...WITH HIGHS IN THE UPPER 70S TODAY AND RAIN ARRIVING INTO MID-SOUTH BY LATE AFTERNOON. NEW ZONES AND GRIDS ARE ALREADY AVAILABLE. AC3 PREV DISCUSSION... /ISSUED 629 AM CDT SUN APR 13 2014/ DISCUSSION... UPDATED FOR 12Z AVIATION DISCUSSION PREV DISCUSSION... /ISSUED 429 AM CDT SUN APR 13 2014/ DISCUSSION... EARLY MORNING TEMPERATURES ARE IN THE MIDDLE TO UPPER 60S ACROSS THE MIDSOUTH. CLOUDY SKIES SHOULD KEEP TEMPERATURES FROM FALLING MUCH MORE RESULTING IN MORNING LOWS ONLY A DEGREE OR TWO COOLER THAN THEY ARE RIGHT NOW. THERE WILL BE A FEW BREAKS IN THE CLOUD COVER THIS MORNING...BUT CLOUD COVER WILL INCREASE DURING THE DAY WITH MOSTLY CLOUDY CONDITIONS AREA WIDE FOR MOST OF THE AFTERNOON. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON...MAINLY WEST OF THE MISSISSIPPI RIVER. SOUTHWEST FLOW IS IN PLACE ACROSS THE MIDSOUTH. A SHORTWAVE TROUGH WILL APPROACH WEST ARKANSAS BY SUNSET. THUNDERSTORMS WILL DEVELOP AHEAD OF THIS FEATURE AND POSSIBLY TRACK AS FAR EAST AS EASTERN ARKANSAS BEFORE SUNSET. A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS IS EXPECTED OVERNIGHT. THE STORM PREDICTION CENTER HAS A LARGE PORTION OF THE MIDSOUTH IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS TODAY/TONIGHT. THIS AREA INCLUDES LOCATIONS GENERALLY WEST OF A LINE FROM DYERSBURG TO OXFORD. CONDITIONS CONTINUE TO TREND IN A DIRECTION MORE FAVORABLE FOR SEVERE THUNDERSTORMS TONIGHT. GUIDANCE DEW POINTS ARE NOW IN THE LOW TO MIDDLE 60S ENHANCING INSTABILITY TO MORE THAN 1000 J/KG OVERNIGHT WITH 0-6KM SHEAR UP TO 50-55KT AND A MID LEVEL JET OF 70 KTS. DIFFLUENCE IN THE UPPER LEVELS WILL HELP TO VENT STORMS EARLY...BUT DIMINISHES A BIT BY 06Z. BEFORE MIDNIGHT FEEL LIKE THE GREATEST THREAT FOR SEVERE WEATHER WILL BE ALONG AND WEST OF THE MISSISSIPPI RIVER...WITH THE FOCUS SHIFTING TO NORTH MISSISSIPPI AFTER MIDNIGHT. LARGE HAIL AND DAMAGING WIND LOOK TO BE THE MAIN THREATS. THESE STORMS WILL LIKELY MOVE INTO THE MIDSOUTH RATHER THAN DEVELOP HERE...SO IT SHOULD GIVE US A BIT MORE TIME TO PREPARE AS WE SEE THINGS INITIATE TO OUR WEST. A FAST MOVING COLD FRONT WILL MARK THE END OF THE THUNDERSTORMS LATE TONIGHT INTO EARLY MONDAY MORNING. ADDITIONALLY...WINDS WILL BE STRONG BOTH AHEAD AND BEHIND THE COLD FRONT. IT LOOKS LIKE SPEEDS SHOULD BE JUST BELOW ADVISORY CRITERIA...SUSTAINED BETWEEN 17 AND 22KT...WITH GUSTS OVER 25 KTS. HIGHS TODAY SHOULD APPROACH 80 DEGREES. COOLER CONDITIONS ARE EXPECTED FOR THE BEGINNING OF THE WORK WEEK. HIGH TEMPERATURES MONDAY MAY OCCUR PRIOR TO SUNRISE WITH FALLING OR STEADY TEMPERATURES FOR MUCH OF THE MIDSOUTH DURING THE DAY. TUESDAY MORNING AND ESPECIALLY WEDNESDAY MORNING WE COULD SEE PATCHY FROST ACROSS THE MIDSOUTH AS LOWS DIP INTO THE MID 30S. A FROST ADVISORY WILL LIKELY BE NEEDED WEDNESDAY AREA WIDE AND POSSIBLY TUESDAY FOR PORTIONS OF THE MIDSOUTH. HIGH TEMPERATURES TUESDAY WILL BE WELL BELOW NORMAL...AS MUCH AS 25 DEGREES BELOW NORMAL...IN THE LOW TO MIDDLE 50S. IT SHOULD BE 10 TO 15 DEGREES WARMER WEDNESDAY AS HIGHS REBOUND INTO THE MID 60S. THE WARMING TREND...ALONG WITH DRY CONDITIONS...WILL CONTINUE THURSDAY. FRIDAY STILL LOOKS QUESTIONABLE. THE GFS STILL BRINGS A VIGOROUS NEGATIVELY TILTED LONGWAVE TROUGH ACROSS THE MISSISSIPPI RIVER VALLEY EARLY FRIDAY. THE ECMWF IS LESS BULLISH IN ITS SOLUTION...BUT HAS TRENDED WETTER. WILL MAINTAIN SLIGHT CHANCE POPS FOR NOW...BUT LIKELY TREND WETTER IN UPCOMING UPDATES. SATURDAY SHOULD BE COOLER AND DRY. 30 && .AVIATION... 18Z TAFS MAIN CONCERN REMAINS TIMING OF TSRA ARRIVAL THIS EVENING. FOR THE 18Z TAFS... HAVE MADE ONLY MINOR TIMING ADJUSTMENTS BASED ON 12Z NAM AND 15Z HRRR MODELS. TS CANNOT BE RULED OUT FOR ANY PERIOD BEYOND 03Z...WITH MULTIPLE UPPER LEVEL IMPULSES LIFTING THROUGH AHEAD OF THE MAIN UPPER TROF. HAVE LIMITED TS/VCTS MENTION TO THOSE PERIODS MOST FAVORABLE. SUSPECT THAT THERE WILL BE LULL DURING THE 11Z TO 15Z PERIOD...BUT WITH IFR/MVFR CIGS PREVAILING WITH SCATTERED SHRA. PWB && .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. MO...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR DUNKLIN-PEMISCOT. MS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR COAHOMA-TUNICA. TN...NONE. && $$
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
905 PM EDT MON APR 14 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH THE AREA FROM THE WEST LATE TONIGHT AND PASS ACROSS THE REGION DURING TUESDAY RESULTING IN WIDESPREAD SHOWERS. MUCH COLDER AIR WILL RUSH IN BEHIND THE FRONT TUESDAY AFTERNOON AS UNSEASONABLY COLD HIGH PRESSURE BEGINS TO BUILD IN ON STRONG NORTHWEST WINDS INTO TUESDAY NIGHT. THE HIGH WILL BUILD OVER THE MID ATLANTIC REGION WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TUESDAY/... AS OF 830 PM EDT MONDAY... SHOWERS HAVE BEEN SLOW TO EVOLVE THIS EVENING WITH MOSTLY LIGHT RAINFALL SEEN ACROSS THE SRN BLUE RIDGE ATTM DESPITE INCREASING MOISTURE OFF EVENING SOUNDINGS. MODELS REMAIN OVERDONE WITH DEGREE OF LIFT UNDER PASSING SHORTWAVES WELL AHEAD OF THE MAIN UPPER TROF THIS EVENING AS THE FLOW REMAINS MORE SW AND FORCING WEAK. LATEST HRRR SEEMS TO HAVE A HANDLE ON LIGHTER SHRA FOR A WHILE LONGER BEFORE THE FLOW DEEPENS/BACKS AND BETTER ISENTROPIC LIFT KICKS IN WITH AN INCREASING SOUTHERLY JET ESPCLY AFTER MIDNIGHT. HAVE ALREADY UPDATED TO LOWER POPS THIS EVENING...THEN QUICKLY REBOUND TO CATEGORICAL MOST SECTIONS OVERNIGHT AS BANDS OF SHRA BEGIN TO LIFT NORTH AHEAD OF THE WAVE AS WEAK INSTABILITY SHIFTS NORTH ACROSS SOUTHERN/EASTERN SECTIONS LATE. GIVEN THIS ALONG WITH STRONGER WIND FIELDS INCLUDED A LOW TOPPED TSRA MENTION ESPCLY FAR WEST JUST AHEAD OF THE FRONT AROUND DAWN AND OUT EAST FOR LOW TOPPED BANDS LATE AS WELL. BUMPED UP LOWS A LITTLE OUT WEST AS EXPECT THE FRONT TO BE JUST SLOW ENOUGH TO KEEP MOST TEMP FALLS FROM OCCURRING UNTIL THE MORNING. OTRW A MILD NIGHT WITH LOWS 50S TO LOWER 60S. WINDS AND LOW TOPPED SHRA THE MAIN CONCERNS DURING TUESDAY WITH STRONG ENOUGH GUSTS TO SUPPORT AT LEAST AN ADVISORY BLUE RIDGE SECTIONS WITH POSSIBLE BANDED SHRA OUT EAST DESPITE LIMITED INSTABILITY. AFTER COORDINATION WITH OTHER OFFICES HAVE DECIDED TO GIVE THE MIDSHIFT ANOTHER LOOK RATHER THAN HOISTING A WIND ADVISORY TONIGHT AS MAY BE CLOSE TO WARNING CRITERIA OVER THE SW FOR A PERIOD TUESDAY AFTERNOON. OTRW MADE SOME ADJUSTS TO TIMING OF THE HEAVIER SHRA AND POSSIBLE ISOLATED TSRA TUESDAY. PREVIOUS DISCUSSION AS OF 320 PM EDT MONDAY... SHOWERS STARTING TO ENTER THE WRN CWA THIS AFTERNOON. 12Z MODELS AND LATEST LOCAL HIGH-RES FAVOR SLOWER TIMING TO THE EAST THRU DUSK...BUT BY MIDNIGHT MOST AREAS WILL SEE LIKELY TO CATEGORICAL POPS AS SERIES OF UPPER VORTS MOVING AHEAD OF THE FRONT SHIFT FROM THE GULF COAST STATES INTO VA. APPEARS THUNDER THREAT WILL STAY ISOLATED AT BEST GIVEN INSTABILITY IS WEAK. GOOD JET DYNAMICS WILL LEAD TO POCKETS OF HEAVY RAIN OVERNIGHT INTO TUESDAY...AS FRONT APPROACHES. MODELS IN AGREEMENT EASING THE FRONT INTO THE MOUNTAINS BY 12Z-15Z TUESDAY AND SHIFTING TO THE EAST OF THE FORECAST AREA BY LATE TUE AFTERNOON. DESPITE FRONT MOVING THROUGH APPEARS ENOUGH LIFT AROUND THE BACKSIDE WITH SOUTHERLY JET TO KEEP THREAT OF RAIN WELL INTO TUESDAY AFTERNOON. RUSH OF COLDER AIR WORKS IN ABOUT 2-4 HOURS BEHIND THE FRONT CHANGING ANY LINGERING PRECIP TO SNOW SHOWERS IN THE HIGHER ELEVATIONS. GIVEN WARMER GROUND THE SNOW AMOUNTS THROUGH TOMORROW WILL BE LESS THAN AN INCH OVER THE RIDGETOPS ABOVE 3000 FT. WILL HAVE TO WATCH FOR ISOLATED FLOODING GIVEN WAVES OF LOW PRESSURE ALONG THE FRONT AND POTENTIAL FOR SOME TRAINING...ALTHOUGH SPEED OF FRONT MAY HINDER IT SOME. STILL QPF LOOKING ON THE ORDER OF 1 TO 1.5 INCHES...THOUGH LOCALLY HIGHER SEEMS LIKELY IN HEAVIER DOWNPOURS. WILL HOLD OFF ON ANY FLOOD WATCHES. EVEN THE RIVER ENSEMBLE FORECASTS ARE NOT TAKING ANY RIVER STAGES ABOVE FLOOD STAGE. WILL HAVE TO WATCH SOUTH BOSTON ON THE DAN THOUGH...GIVEN AMOUNTS SEEM SIMILAR TO LAST WEEK. THE OTHER ISSUE SHOULD BE WINDS BEHIND THE FRONT AS 6 HR PRESSURE RISES ON THE ORDER OF 6 TO 12 MB ARE EXPECTED. MADE SOME ADJUSTMENTS UP IN WIND GUSTS TO 40 KNOTS ACROSS THE SRN BLUE RIDGE AND ADJACENT AREAS. WILL ALLOW FOR ONE MORE RUN OF THE MODELS AS CLOUD COVER WILL TEMPER SOME OF THE GUSTS ABOVE INVERSION. HWO WILL MENTION WIND ADVISORY POTENTIAL. AS FOR TEMPS WILL BE SEEING SLOW FALLING AT BEST OVERNIGHT WITH CONTINUED SOUTH FLOW...WITH SHOWERS HELPING TO COOL IT SOME. TOMORROW WILL BE MILD IN THE FAR EAST BUT TEMPS WILL BE FALLING TO THE FREEZING MARK INTO THE UPPER 30S ACROSS THE MOUNTAINS BY DUSK. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 355 PM EDT MONDAY... H85 TEMPS PLUNGE BEHIND STRONG COLD FRONT TUESDAY NIGHT...NEARING -12C PER THE GFS. MOISTURE DRIES OUT RATHER QUICKLY ALOFT...BUT SHOULD BE ENOUGH TO GENERATE AN HOUR OR TWO OF UPSLOPE SNOW SHOWERS ACROSS WESTERN GREENBRIER WHERE A QUICK HALF INCH OR LESS MAY FALL ABOVE 2500 FEET. SNOW SHOWERS/FLURRIES MAY FALL FOR A BRIEF TIME DOWN TO BLUEFIELD...BUT NO ACCUMULATION IS EXPECTED. SKIES SHOULD CLEAR RAPIDLY....WITH STRONG DOWNSLOPE...AND H85 JET NEAR 50KTS SHOULD PRODUCE WIND ADVISORY CRITERIA ACROSS NW NC/EXTREME SW VA AT THE VERY LEAST. POSSIBLY A SMALL WINDOW TUESDAY EVENING WITH HIGH WIND CRITERIA GUSTS NW NC. 1030MB HIGH PRESSURE NOSES ACROSS THE MOUNTAINS QUICKLY...AND MOS GUIDANCE IS SOLIDLY AT OR BELOW 32F FOR LOWS WED MORNING EVEN ACROSS THE PIEDMONT/SOUTHSIDE. BECAUSE OF THIS ISSUED A FREEZE WATCH EAST OF THE BLUE RIDGE. WINDS SHOULD HOLD THROUGH MUCH OF THE NIGHT...AND SOMETIMES LOWS COME IN A FEW DEGREES WARMER IN THIS SETUP. THUS THE CHANCE OF A WIDESPREAD FREEZE MAY BE MARGINAL ACROSS THE SOUTHEASTERN CWA...SOUTHSIDE/NC PIEDMONT. MUCH BETTER CHANCE NORTH OF THIS REGION. SURFACE HIGH PRESSURE WEDGING DOWN THE APPALACHIANS IS PRETTY MUCH LOCKED IN THROUGH THURSDAY NIGHT...WITH DRY SUNNY DAYS AND COLD NIGHTS EXPECTED. WITH LESS WIND WEDNESDAY NIGHT AND DEWPOINTS INTO THE TEENS WED PM...CONDS MAY BE EVEN MORE FAVORABLE FOR MORE WIDESPREAD FREEZE...WITH ANOTHER WATCH NECESSARY WED NIGHT/THURS MORNING. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 355 PM EDT MONDAY... WEAK TROUGH THROUGH THE MIDWEST EVENTUALLY PUSHES EAST...AND WEDGING HIGH PRESSURE EVENTUALLY DEPARTS THIS WEEKEND. WITH A RATHER DRY ANTECEDENT AIRMASS...QUESTIONABLE IF THIS MIDWEST TROUGH PRODUCES ANY PRECIP ONCE IT ARRIVES ACROSS THE OHIO VALLEY AND MIDDLE ATLANTIC THIS WEEKEND. OP GFS IS FAR MORE WET THAN THE ECMWF. THUS...POPS WERE KEPT RATHER LOW. A ZONAL UPPER FLOW TAKES SHAPE BY LATE WEEKEND INTO EARLY NEXT WEEK...WITH UNEVENTFUL AND DRY WEATHER CONTINUING ACROSS THE REGION. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... AS OF 705 PM EDT MONDAY... VFR CIGS THIS EVENING WILL GRADUALLY DETERIORATE TO MVFR THEN IFR AFTER MIDNIGHT WITH SHOWERS ON THE INCREASE BY LATE TONIGHT. HOWEVER WITH THE LATEST RADAR TRENDS AND SHORT TERM GUIDANCE INDICATING ONLY VERY LIGHT SHOWERS EARLY AND PERHAPS A BREAK BEFORE THE MORE SUBSTANTIAL RAINFALL ARRIVES LATER...HAVE SLOWED DOWN THE ONSET OF SUB-VFR VSBYS THIS EVENING. APPEARS ONCE THE MAIN AREA OF LIFT STARTS TO APPROACH LATER TONIGHT WILL SEE HEAVIER SHOWERS RESULT IN VSBYS FALLING TO HIGH END IFR/LOW END MVFR INTO TUESDAY MORNING. A TSRA IS POSSIBLE AS SHOWERS MAY ALIGN IN A NARROW BAND JUST AHEAD OF THE FRONT AROUND DAYBREAK OVER THE FAR WEST BUT NOT ENOUGH COVERAGE/THREAT OVERALL TO HAVE IN TAFS. COLD FRONT SHOULD BE PASSING THE BLF/LWB REGION AROUND 13Z/9AM AND THEN EAST TO BCB/ROA BY NOON AND THE EASTERN SITES 18-20Z. FRONT WILL BE ACCOMPANIED BY A QUICK BAND OF HEAVIER RAINFALL AND SHIFTING WINDS AROUND TO THE NW WITH GUSTS TOPPING 30-40 KTS OVER THE MOUNTAIN LOCATIONS. LOWER IFR/LIFR UPSLOPE DRIVEN CIGS LIKELY AROUND KBLF WITH PRECIP CHANGING TO SNOW SHOWERS QUICKLY BEHIND THE FRONT AT BLF AND POSSIBLY LWB IN THE AFTERNOON. RAIN SHOULD PULL EAST OF THE BLUE RIDGE SHORTLY AFTER MIDDAY TUESDAY WITH CIGS IMPROVING TO HIGH END MVFR BY LATE IN THE DAY. PRECIP AND LOWER CIGS MAY LINGER OUT EAST BEHIND THE FRONT WITH MVFR CONDITIONS AT LYH/DAN PERSISTING BEHIND THE BOUNDARY UNTIL EARLY EVENING. STRONG NW WINDS WILL REMAIN AN ISSUE INTO TUESDAY NIGHT WITH ANOTHER PERIOD OF GUSTS OVER 40 KNOTS POSSIBLE. HOWEVER SMALL WINDOW AS HIGH PRESSURE BUILDS IN WEDNESDAY MORNING WITH SPEEDS DECREASING TO BELOW 10 KTS MOST SPOTS BY DAYBREAK WEDNESDAY. MUCH DRIER AIR WORKS IN BEHIND THE FRONT WEDNESDAY WITH STRONG HIGH PRESSURE WEDGED IN FROM THE NE. THIS SHOULD ALLOW A RETURN TO WIDESPREAD VFR WITH THIS SCENARIO CONTINUING THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND AND THE NEXT COLD FRONT TO THE NW. THIS FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW AND WEAK ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. THIS SYSTEM MAY BRING MVFR CIGS TO THE MOUNTAINS SATURDAY ALONG WITH A FEW SHOWERS OTRW VFR ELSW TO START THE WEEKEND. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR VAZ022>024-032>035-043>047-058-059. NC...FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ003>006-019-020. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH/WP SHORT TERM...KM LONG TERM...KM AVIATION...JH/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
343 PM CDT SUN APR 13 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 343 PM CDT SUN APR 13 2014 BUSY PERIOD TONIGHT INTO TOMORROW MORNING AS A LOW PRESSURE SYSTEM TRACKS THROUGH NORTHERN ILLINOIS. HEAVY RAIN...SNOW...AND STRONG WINDS ARE ALL CONCERNS TONIGHT INTO TOMORROW MORNING. CURRENTLY...THE LEAD MID LEVEL TROUGH IS PROPAGATING TO THE NORTH ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH SOME LOW LEVEL CONVERGENCE OCCURRING ALONG A SOUTHWEST TO NORTHEAST ORIENTED WARM FRONT THAT RUNS FROM SOUTHEAST IOWA THROUGH SOUTHERN WISCONSIN. MODERATE TO HEAVY RAIN HAS ALREADY MOVED INTO NORTHEAST IOWA AND SOUTHWEST WISCONSIN AND WILL CONTINUE TO TRACK TO THE NORTHEAST INTO THIS EVENING AS THE SURFACE LOW MOVES UP IN THE REGION. MOST OF THE 0-3KM MUCAPE THAT THE 13.19Z RAP SHOWS STAYS IN NORTHERN ILLINOIS AND DOES NOT REACH THE REGION. SO...THINKING THAT THERE SHOULD NOT BE MUCH LIGHTNING WITH THIS RAIN INTO THE EVENING HOURS. WITH 1 TO 2 INCHES OF RAIN STILL FORECAST FOR THE SAME AREAS THAT WERE HIT BY 1 TO 3 INCHES OF RAIN YESTERDAY...HAVE KEPT THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN. TO THE WEST SIDE OF THE SYSTEM WE GO WHERE THE CONCERN IS ON WHEN THE THERMAL PROFILE WILL COOL ENOUGH TO CHANGE THE PRECIPITATION OVER TO ALL SNOW ALONG WITH HOW WINDY IT WILL BE. IN REGARD TO THE SNOW...WITH LOW TO MID LEVEL COLD AIR ADVECTION KICKING IN THIS EVENING AS THE LOW DEEPENS...THE PRECIPITATION TYPE WILL BE DEPENDENT UPON WHAT THE SURFACE TEMPERATURES ARE. LOOKING OUT WEST RIGHT NOW...MOST OBSERVATIONS THAT ARE REPORTING SNOW ARE IN THE 30F TO 35F RANGE THOUGH SOME OF THESE TEMPERATURE DROPS APPEAR TO BE DUE TO EVAPORATIVE COOLING THANKS TO THE PRECIPITATION FALLING THROUGH THE COLUMN. BASED ON THE 13.19Z RAP & 13.12Z NAM/GFS SOUNDINGS...IT LOOKS LIKE THE CHANGE OVER SHOULD OCCUR TO ALL SNOW THIS EVENING BETWEEN 8-10PM IN NORTH CENTRAL IOWA AND SOUTHEAST MINNESOTA. THIS CHANGE OVER WILL THEN GRADUALLY PUSH EASTWARD INTO WESTERN WISCONSIN OVERNIGHT. SNOW TOTALS ARE PROBLEMATIC AS A RESULT SINCE A LOT HINGES ON HOW FAST THE CHANGE OVER OCCURS...IS THERE STRONG FORCING STILL THERE AS THE COLD AIR ARRIVES...AND ALSO IF THERE EVEN IS ICE THERE AS A LOT OF THE SOUNDINGS SHOW A DRY LAYER BETWEEN -8C TO -20C. MOST OF THE 13.12Z COBB DATA FROM THE NAM/GFS IS SHOWING ABOUT 1 TO 2 INCHES OCCURRING OVERNIGHT THOUGH A LOT OF THE SREF DATA IS MUCH HIGHER THAN THAT. GIVEN THE NUMBER OF NEGATIVES WORKING AGAINST THIS...TRENDED TOWARD THESE LOWER TOTALS WHICH STILL ARE A BIT HIGHER THAN WHAT PREVIOUSLY WAS BEING FORECAST BY GUIDANCE. THE MAIN SNOW SHOULD FALL BETWEEN 7PM-1AM IN NORTHEAST IOWA/SOUTHEAST MINNESOTA AND THEN BETWEEN 1AM-7AM IN WESTERN WISCONSIN/FAR NORTHEAST IOWA. WINDS WILL CONTINUALLY INCREASE THROUGH TONIGHT AS THE PRESSURE GRADIENT TIGHTENS UP WITH THE LOW. THE STRONGEST LOW LEVEL WINDS HAVE ALREADY DEVELOPED ACROSS WESTERN IOWA WHERE 30 TO 40KT WINDS ARE FAIRLY WIDESPREAD IN THE AREA WHERE SNOW IS FALLING. CONCERNED THAT THESE CONDITIONS WILL TRANSLATE EASTWARD INTO NORTHEAST IOWA AND SOUTHEAST MINNESOTA THIS EVENING. THE STRONGEST WINDS LOOK LIKE THEY WILL MAINLY BE IN NORTHEAST IOWA WITH BUFKIT SOUNDINGS SHOWING SOME 35 TO 40KT WINDS MIXING DOWN AS THE SNOW IS COMING DOWN. DISCUSSED THE IDEA OF DOING A WINTER WEATHER OR WIND ADVISORY WITH MPX/DMX...BUT DECIDED THAT THE WIND GUSTS MAY NOT HIT ADVISORY CRITERIA AND SNOW AMOUNTS MAY NOT BE HIGH ENOUGH TO CAUSE A LARGE IMPACT. CONDITIONS WILL HAVE TO BE MONITORED CLOSELY THIS EVENING FOR A POSSIBLE QUICK UPGRADE WITH THE 9PM TO 3AM TIME FRAME THE MAIN PERIOD OF CONCERN. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 343 PM CDT SUN APR 13 2014 THE MAIN STORIES THROUGH THIS WEEK ARE WITH THE POTENTIAL ACCUMULATING SNOW ON TUESDAY NIGHT/WEDNESDAY AND ANOTHER SYSTEM LATER IN THE WEEK. MORE FOCUS WENT INTO THE TUESDAY NIGHT/WEDNESDAY SYSTEM SINCE THERE IS QUITE A BIT OF UNCERTAINTY WITH THE LATE WEEK SYSTEM. THE 13.12Z NAM/GFS DEVELOPS A BAND OF SNOW ACROSS NORTHERN WISCONSIN LATE TUESDAY NIGHT WHILE THE 13.12Z ECMWF KEEPS US DRY. SOME ACCUMULATING SNOW IS LIKELY IN THE NAM/GFS SCENARIOS THOUGH ENOUGH UNCERTAINTY IS THERE THANKS TO THE ECMWF. IT LOOKS LIKE WE GET WARM SECTORED ON WEDNESDAY AS THE SYSTEM STALLS OUT WITH THE PRECIPITATION SETTING UP FROM UPPER MICHIGAN DOWN THROUGH CENTRAL IOWA ON THURSDAY. THE 13.12Z GFS THEN SPINS UP A POTENT SYSTEM FOR FRIDAY THAT TRACKS THROUGH WISCONSIN WHILE EH ECMWF HARDLY HAS A LOW DEVELOPING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1233 PM CDT SUN APR 13 2014 WIDESPREAD -RA/RA AND SHRA WILL SPREAD ACROSS THE TAF SITES THIS AFTERNOON AND EARLY THIS EVENING. VSBYS WILL MAINLY BE IN THE 1 TO 4SM RANGE WITH IFR CIGS THRU EARLY THIS EVENING. COLDER AIR THEN SPREADS ACROSS THE AREA THIS EVENING WITH THE RAIN MIXING WITH/ CHANGING TO SNOW THRU THE MID EVENING HOURS. IFR CIGS/VSBYS EXPECTED DURING THE EVENING INTO OVERNIGHT HOURS. PRESSURE GRADIENT OVER THE AREA WILL TIGHTEN THIS AFTERNOON AND REMAIN QUITE TIGHT TONIGHT INTO MONDAY. NORTH WINDS OF 15-20KTS G25-30KTS EXPECTED LATE THIS AFTERNOON/EVENING...BECOMING NORTHWEST FOR LATER TONIGHT/MON. DRIER LOW LEVEL AIR THEN EXPECTED TO SPREAD WEST TO EAST ACROSS THE AREA LATE TONIGHT AND MONDAY. THE PRECIP LOOKS TO END AROUND 07Z AT KRST AND AROUND 09Z AT KLSE...WITH VSBYS BECOMING VFR AND CIGS RISING INTO MVFR/VFR FOR LATE TONIGHT AND MON. && .HYDROLOGY... ISSUED AT 343 PM CDT SUN APR 13 2014 WITH MODERATE TO AT TIMES HEAVY RAIN FALLING INTO TONIGHT...WILL KEEP THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN. WITH 1 TO 3 INCHES OF RAIN FALLING LAST NIGHT ACROSS THIS AREA AND ANOTHER 1 TO 2 INCHES POSSIBLE...SAW NO NEED TO DROP IT. THERE DOES NOT APPEAR TO BE MUCH INSTABILITY THAT MAKES IT UP IN THE REGION THIS AFTERNOON INTO TONIGHT...SO MOST OF THE RAIN SHOULD NOT FALL AT A GREAT ENOUGH OF A RATE TO PROMPT FLASH FLOODING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR WIZ043-044-053>055-061. MN...NONE. IA...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR IAZ030. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION.....RRS HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1051 PM MDT SAT APR 12 2014 .SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT) ISSUED AT 340 PM MDT SAT APR 12 2014 CONVECTION HAS BEEN STEADILY INITIATING SINCE NOON MAINLY ALONG AND WEST OF I-25 WITH EVEN A FEW LIGHTNING STRIKES NOTED IN CARBON COUNTY. CONVECTIVE ACTIVITY WILL CONTINUE TO BLOSSOM INTO THE EVENING HOURS WITH LIFTED INDICES AROUND -1C AND PROGD SBCAPE VALUES OF 200-500 J/KG ARE REALIZED. AT THE SFC...WINDS HAVE TURNED NORTHEAST THIS AFTERNOON AS PRESSURES HAVE BEEN STEADILY FALLING ACROSS COLORADO. AT 20Z...THE BEST PRESSURE RISES WERE FOUND ACROSS MONTANA AND WRN NORTH DAKOTA. THESE PRESSURE RISES WILL SHIFT SOUTH TONIGHT AS THE COLD AIR MASS SETTLES IN. SATELLITE PIX STILL SHOW TWO SEPARATE SHORTWAVES...ONE DIVING SE THRU THE PACNW AND THE SRN STREAM ACCELERATING ENE TOWARDS THE FOUR CORNERS. THE SRN STREAM SHORTWAVE WILL EJECT ONTO THE CENTRAL PLAINS SUNDAY MORNING...WHILE THE NRN STREAM ENERGY FOLLOWS...TAKING AIM ON THE CENTRAL ROCKIES. ALTHO THE BULK OF THE SRN STREAM SHORTWAVE WILL REMAIN SOUTH OF THE CWA...IT HAS BEEN EFFECTIVE IN ADVECTING PACIFIC MOISTURE AHEAD OF THE TRAILING AND STRONGER NRN STREAM DISTURBANCE. AS THE COLD AIR MASS SAGS SOUTH TONIGHT...PERSISTENT WEST/SOUTHWEST FLOW ABOVE IT WILL SET-UP FAVORABLE OVERRUNNING/ISENTROPIC LIFT. ADDITIONALLY... STRONG NORTHEAST WINDS WILL ENHANCE OROGRAPHICS...ESPECIALLY ALONG THE LARAMIE AND SNOWY RANGES. H3 JET COUPLING OF RRQ/LFQ WILL FURTHER ENHANCE MOIST ASCENT. PROGD BUFKIT SOUNDINGS ALSO SHOWS SATURATION WITHIN THE BEST DENDRITIC GROWTH LAYER DURING THE DAY ON SUNDAY. EVERYTHING STILL POINTS TO A WIDESPREAD MODERATE TO HEAVY SNOW EVENT MAINLY IMPACTING SOUTHEAST WYOMING. HAVE KEPT SNOW AMOUNTS FAIRLY SIMILAR TO THOSE INHERITED...POINTING TO 4 TO 8 INCHES BELOW 7500 FEET IN SE WY...WITH 8 TO 14 INCHES ABOVE. THE EXCEPTION WILL BE ACROSS LOWER ELEVATIONS OF CARBON COUNTY AND MOST OF THE WESTERN NEBRASKA PANHANDLE WHERE EITHER LESS FAVORABLE CONDITIONS EXIST OR LOWER ELEVATIONS DELAYS TRANSITION TO SNOW. THE OTHER CONCERN WILL BE BLOWING SNOW AS WINDS GUST UP TO 35 MPH. THE ONE QUESTION THAT REMAINS IS WHAT IMPACT IF ANY THE STEEPER SUN ANGLE HAS DURING THE DAYTIME...ESPECIALLY ON ROADWAYS. HOWEVER... THINK SNOWFALL RATES WILL BE SUFFICIENT TO OVERCOME THIS. IN AN EARLIER UPDATE...UPGRADED THE WINTER STORM WATCH TO A WARNING FOR MUCH OF SOUTHEAST WYOMING. HAVE ALSO ISSUED ADVISORIES IN COUNTIES CLOSEST TO THE NEBRASKA STATELINE AND NRN SIOUX COUNTY. DELAYED THE BEGINNING TIME ACROSS EXTREME SOUTHEAST WYOMING TO 3 AM...AS THE COLDER AIR WILL GET IN A BIT LATER THAN EARLIER ANTICIPATED. OTHERWISE...SNOW WILL COME TO AN END SUNDAY EVENING...SO THE 00Z MONDAY END TIME OF THE HAZARD STILL LOOKS ON TRACK. TEMPS ARE GOING TO BE SIGNIFICANTLY COLDER SUNDAY WITH HIGHS STRUGGLING TO GET OUT OF THE 20S MANY AREAS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 340 PM MDT SAT APR 12 2014 MONDAY...MODERATELY STRONG NORTHWEST FLOW ALOFT WILL PRODUCE A BREEZY TO WINDY DAY WITH ONLY SLIGHT MODIFICATION IN MAXIMUM TEMPERATURES DUE TO HIGH ALBEDO FROM THE RECENT SNOWPACK...THOUGH STILL EXPECT HIGH TEMPERATURES TO CLIMB ABOVE FREEZING AT LOWER ELEVATIONS DUE TO RATHER HIGH MID APRIL SUN ANGLE AND DOWNSLOPE LOW LEVEL WINDS. TUESDAY...DECENT WARMING TREND EXPECTED AS THE FLOW ALOFT BACKS TO WEST NORTHWEST IN ADVANCE OF THE NEXT APPROACHING SHORTWAVE TROUGH ALOFT FROM MONTANA AND IDAHO...BOOSTING MAXIMUM TEMPERATURES WELL INTO THE 50S AND SOME LOWER 60S DUE TO DEVELOPING SURFACE LEE TROUGHING AND 700 MB TEMPERATURES CLIMBING TO 0 CELSIUS. WEDNESDAY...NEXT SHORTWAVE TROUGH ALOFT PASSAGE ALONG WITH ITS ASSOCIATED COLD FRONTAL PASSAGE WILL BRING COOLER TEMPERATURES AND SCATTERED SHOWERS DUE TO LIFT FROM CYCLONIC FLOW ALOFT AND ADEQUATE LOW AND MID LEVEL MOISTURE. THURSDAY...AFOREMENTIONED SHORTWAVE TROUGH ALOFT MOVES INTO THE CENTRAL PLAINS STATES...WITH LEFTOVER SCATTERED SHOWERS ONGOING INTO THE AFTERNOON HOURS ALONG AND EAST OF INTERSTATE 25. RESIDUAL CLOUD COVER AND PROJECTED THICKNESSES AND 700 MB TEMPERATURES WILL YIELD HIGH TEMPERATURES IN THE UPPER 30S AND 40S AT LOWER ELEVATIONS. FRIDAY...TYPICAL MID APRIL SYNOPTIC PATTERN EXPECTED WITH PROGRESSIVE SHORTWAVE TROUGHS ALOFT...AND OUR COUNTIES WILL BE IN THE WARM SECTOR MUCH OF THE DAY IN ADVANCE OF THE NEXT SHORTWAVE TROUGH ALOFT MOVES ACROSS MONTANA AND WYOMING...THUS YIELDING MAXIMUM TEMPERATURES IN THE 50S AND LOWER 60S. ISOLATED SHOWERS EXPECTED OVER THE HIGHER TERRAIN DUE TO DIFFERENTIAL HEATING... INCLUDING THE NORTHERN LARAMIE...SNOWY AND SIERRA MADRE RANGES AND OVER THE PINE RIDGE FROM LUSK TO NEAR CHADRON. SATURDAY...DRYING OUT PERIOD IN THE WAKE OF THE SHORTWAVE TROUGH PASSAGE. SLOW WARMING TREND ON TAP BASED ON PROJECTED 1000-500 MB THICKNESSES AND 700 MB TEMPERATURES...NEAR 5610 METERS AND 2 CELSIUS...RESPECTIVELY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 1048 PM MDT SAT APR 12 2014 LATEST HRRR FORECAST MAY BE A LITTLE TOO BULLISH ON WIDESPREAD IFR/LIFR AS WE ARE STILL VFR AT MOST LOCATIONS. BASED ON THIS TREND...DECIDED TO HOLD OFF A COUPLE HOURS ON IFR CONDITIONS FOR AIRPORTS EAST OF THE LARAMIE RANGE. EVENTUALLY...THE WIDESPREAD IFR/LIFR DOES MAKE IT INTO OUR FORECAST AREA...SAY AFTER 08 TO 09Z AND PERSISTS THROUGH MUCH OF SUNDAY. SNOW ENDS LATE AFTERNOON AND EARLY EVENING WITH IMPROVING CONDITIONS. && .FIRE WEATHER... ISSUED AT 300 AM MDT SAT APR 12 2014 NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS A SIGNIFICANT SPRING SNOWSTORM BRINGS SIGNIFICANT SNOW ACCUMULATIONS TO MUCH OF THE AREA. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER WEATHER ADVISORY UNTIL 6 PM MDT SUNDAY FOR WYZ102. WINTER STORM WARNING UNTIL 6 PM MDT SUNDAY FOR WYZ101-103>105- 110-114. WINTER STORM WARNING FROM 3 AM TO 6 PM MDT SUNDAY FOR WYZ106-107- 115>118. WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM MDT SUNDAY FOR WYZ108- 112-119. NE...WINTER WEATHER ADVISORY UNTIL 6 PM MDT SUNDAY FOR NEZ095. && $$ SHORT TERM...HAHN LONG TERM...RUBIN AVIATION...CLAYCOMB FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
406 AM CDT Tue Apr 15 2014 .SHORT TERM...(Today and Tonight) Issued at 302 AM CDT TUE APR 15 2014 Extreme fire danger conditions return for portions of north central Kansas followed by strong winds and warmer temperatures. Departing upper trough continues to track eastward over the Mid Atlantic region as quiet and cold conditions have settled across northeast Kansas this morning. A quick rebound in temperatures is on tap for today as variable winds shift to the south, advecting warmer air into the area. A surface trough, currently positioned over northern Colorado, deepens eastward this afternoon, increasing southwesterly winds 15 to 20 MPH west to east after 1 PM across north central areas. Sounding profilers depict strong mixing through 800 MB across the area, lowering dewpoint temperatures into the lower 20s and upper teens. Please refer to the fire weather discussion below for additional details. Have issued a Red Flag Warning for low humidity and gusty winds for this afternoon into the early evening across portions of north central Kansas. Highs today are expected to recover into the upper 50s and low 60s by late afternoon underneath sunny skies. Southerly winds increase between 20 and 25 mph sustained this evening as a strong 70 kt low level jet develops coincident with the upper trough over the northern plains. The increased mid level clouds from the passing system and the mixed boundary layer should keep overnight lows much warmer in the lower 40s. .LONG TERM...(Wednesday through Monday) Issued at 302 AM CDT TUE APR 15 2014 Early Wednesday morning, a 60 kt low level jet will be oriented across the forecast area. While this jet will weaken and gradually slide to the east, morning mixing will likely bring some rather strong wind gusts to the surface by 10 AM or so...potentially in the 45 to 50 mph range. Have not quite gone that high in the forecast given high cloud cover and a fairly rapid decrease in wind speeds by late morning, but it is possible. Expect a rather warm day on Wednesday although a cold front will make its way into the northwest half of the area by late afternoon. Will likely have a thermal ridge very near the frontal boundary which would focus the warmest temps near and just ahead of the front. With the wind, warm temps, and relatively dry low levels, will have fire weather concerns for Wed as well...more details in the fire weather section below. The front will continue to slowly progress through the area overnight, although it`s expected to be a dry front through midnight or so. Beyond midnight, and incoming short wave trough will interact with the frontal zone as it becomes nearly stationary near/just south of the forecast area. This will result in an enhanced area of vertical motion spreading east across KS, focused mainly across the southern 2/3 of the forecast area. Expect this to persist through the day on Thursday before the wave passes overhead on Thursday evening and subsidence takes over. Expect rather persistent light precipitation with this system. THE ECMWF is on the dry side of model guidance in terms of total QPF while it seems that the NAM/GFS are probably picking up on some of the expected mesoscale lift enhancements and producing slightly higher amounts. Dry advection from the north will provide a sharp cutoff to the precipitation, and have reduced POPs in northern KS with some potential for areas near the Nebraska border to end up dry if the dry advection is strong enough. Precip type will be predominantly rain although there seems to be a period early Thursday morning when it could change to snow especially on the northern fringes of the precip area. Accumulation appears unlikely at this time. Will see a nice warm-up for the weekend as upper ridging returns to the area on the heels of the Thursday system. Expect moisture advection to bring dewpoints well into the 50s by Saturday in advance of the next upper trough. This system has trended slightly slower over recent model runs but otherwise fairly consistent in bringing another chance for widespread precipitation to the area. Do not expect much instability with this storm system but could still see periods of thunder. This looks to be a pretty widespread rain with the best chances Saturday night into Sunday, but do not expect particularly heavy amounts. Should also see continued warm temperatures throughout the weekend with highs in the upper 60s, and even warmer behind the system on Monday as little to no cold advection is expected behind the trough. && .FIRE WEATHER...(This Afternoon and Wednesday) Issued at 4 AM CDT TUE APR 15 2014 Expect southerly winds over north central Kansas to quickly increase after 12 PM as a surface trough rapidly deepens over the central and northern plains. 850 MB winds increase from near 10 KTS to over 30 KTS by 3 PM this afternoon, mixing dewpoint temperatures down into the upper teens. Decided to use a combination of the latest RAP and NAM, with a lean towards the RAP as previous events trended drier than forecast. These extreme fire danger conditions with the continuation of critical fuels has prompted a Red Flag Warning after 1 PM for Cloud, Republic, and Ottawa counties. Very high fire danger conditions exist across the remainder of the CWA this afternoon into the early evening. It is important to note the southerly winds will increase through the evening and overnight hours with gusts near 30 MPH and sustained speeds between 20 and 25 mph. For Wednesday, should start the day windy with lower than normal sunrise RH. While there will be some modest moisture increase with the southerly winds, expect it to be shallow. Deep mixing by late morning to early afternoon will pull drier air to the surface along with potentially very strong wind gusts. At the same time, the incoming cold front will bring a zone of much lighter winds as far east as Manhattan by mid afternoon although RH may be lowest near the front. Behind the front, temperatures will not be much cooler and winds will increase out of the northwest. All-in-all, expect the most volatile combination of strong wind and low RH to be southeast of an Abilene to Seneca line through the day...many of the areas to see the highest rainfall totals this past weekend. Current MinRH forecast is in the 22 to 27 percent range but could see it ending up a bit lower while winds in this area gust to 40+ mph. && .AVIATION...(For the 06Z TAFs through 06Z Tuesday Night) Issued at 1146 PM CDT MON APR 14 2014 VFR conditions expected through the taf period. && .TOP WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING until 9 AM CDT this morning FOR KSZ008>012- 020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...Bowen LONG TERM...Barjenbruch AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1030 PM MDT MON APR 14 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1252 PM MDT MON APR 14 2014 EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT. ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE CWA. ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND W-SW WINDS DEVELOP LATE TONIGHT. MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA. SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH. MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP (ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH AT THIS TIME. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 237 PM MDT MON APR 14 2014 MODEL SOLUTIONS REMAIN IN CLOSE AGREEMENT THROUGH THE END OF THE WORK WEEK AND THEN BEGIN TO DIVERGE THROUGH THE WEEKEND AS AN UPPER TROUGH MOVES ACROSS THE NORTHERN PLAINS IN THE NORTHERN BRANCH OF THE UPPER FLOW AND A SHORT WAVE TROUGH EMBEDDED IN THE SOUTHERLY BRANCH TRIES TO COME INTO PHASE WITH THE NORTHERLY BRANCH. THE GFS REMAINS THE MORE PROGRESSIVE SOLUTION WHILE THE ECMWF LAGS BEHIND NEARLY 24 HOURS. THIS IS PROVING TO BE TROUBLESOME WITH THE TIMING OF THE PRECIPITATION THAT IS POSSIBLE BETWEEN A LATE FRIDAY TO LATE SATURDAY TIME FRAME. HAVE GONE WITH SOME KIND OF BLENDED COMPROMISE SOLUTION FOR THE FRIDAY THROUGH SUNDAY TIME PERIOD WITH RAIN SHOWERS TRANSITIONING TO A FEW THUNDERSTORMS AND BACK TO RAIN SHOWERS ON SATURDAY AND SATURDAY NIGHT. EXPECT DRY AND WARMER CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND INTO THE BEGINNING OF NEXT WEEK AS A LARGE RIDGE AMPLIFIES OVER THE WESTERN UNITED STATES AND MOVES EAST OVER THE ROCKIES AND HIGH PLAINS REGION. BACKTRACKING TO THE MID-WEEK SYSTEM... EXPECT RAIN TO DEVELOP EAST OF THE ROCKIES LATE WEDNESDAY AND TRANSITION TO SNOW AS IT SPREADS ACROSS THE FORECAST AREA WEDNESDAY NIGHT. EXPECT A TRANSITION BACK TO RAIN DURING THE DAY ON THURSDAY...BUT MAY END UP STAYING MORE SNOW THROUGH THURSDAY MORNING IF TEMPERATURES REMAIN COLDER AND WET BULB ZERO TEMPERATURES ARE COLDER AS THEY WERE WITH THE LAST SYSTEM THAT DEPOSITED SNOW ACROSS THE FORECAST AREA. EXPECT PRECIPITATION TO END FROM WEST TO EAST ACROSS THE FORECAST AREA LATE IN THE DAY ON THURSDAY. TEMPS WILL WARM BRIEFLY ON FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1030 PM MDT MON APR 14 2014 KGLD...VFR CONDITIONS THROUGH THE PERIOD. WEST/SOUTHWEST WINDS AROUND 10KTS AT TAF ISSUANCE WILL INCREASE A BIT TOWARD 15KTS AROUND 09Z AND CONTINUE THROUGH 14Z. AFTER 14Z WINDS EXPECTED TO INCREASE WITH SUSTAINED SPEEDS OF 15-20KTS WITH GUSTS NEAR 30KTS THROUGH 02Z BEFORE DIMINISHING TO AROUND 12KTS THROUGH THE REST OF THE TAF PERIOD. ONLY HIGH CLOUDINESS EXPECTED...MAINLY DURING THE AFTERNOON AND EVENING. KMCK...VFR CONDITIONS THROUGH THE PERIOD. WEST/SOUTHWEST WINDS AROUND 06KTS EXPECTED THROUGH 16Z. AFTER 16Z SOUTHWEST WINDS AROUND 15KTS WITH GUSTS NEAR 25KTS EXPECTED THROUGH 02Z BEFORE BACKING TO THE SOUTH AROUND 11KTS FOR THE REMAINDER OF THE TAF PERIOD. ONLY HIGH CLOUDINESS EXPECTED...MAINLY DURING THE AFTERNOON AND EVENING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...LOCKHART AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EDT TUE APR 15 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT TUE APR 15 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD -SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE ERN LAKE. TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 459 AM EDT TUE APR 15 2014 ...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO THURSDAY... SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON 290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS. ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS. NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL SOMEWHERE IN THE WESTERN CWA. EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF. THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1 INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1 RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA. SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM. FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND 850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER. RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO PREFERRED BY HPC. NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE WEEKEND. ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85 MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES. THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT LAKES. MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF THESE DAYS ENDS UP DRY WITH SOME SUNSHINE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 134 AM EDT TUE APR 15 2014 ALTHOUGH AN UPPER DISTURBANCE WL BE PASSING OVER THE UPR LKS THIS MRNG AND AIRMASS IS SUFFICIENTLY COLD FOR LK EFFECT SHSN...DRY AIRMASS SHOWN ON THE 00Z INL AND YPL RAOBS INDICATE VFR CONDITIONS WL PREDOMINATE. BEST CHC FOR SOME MVFR CONDITIONS WL BE AT CMX AND IWD WITH A MORE UPSLOPE NNW FLOW...BUT INCLUDED ONLY TEMPO GROUPS IN THE FIRST 6 HRS NOW. ARRIVAL OF SFC HI PRES RDG WL BRING VFR CONDITIONS THIS EVNG. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 459 AM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. 30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 459 AM EDT TUE APR 15 2014 GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR MIZ001>005-009>011-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...KC MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1138 PM CDT Mon Apr 14 2014 .UPDATE: Issued at 830 PM CDT Mon Apr 14 2014 Band of snow has effectively left our CWA leaving behind a region of drizzle in its wake, now primarily confined to parts of southwest IL. The clearing line has made it almost to Jacksonville, IL, just passed thru Bowling Green, MO and near Rolla, MO. At its current rate, the skies are expected to clear for nearly the entire CWA by 06z, just in time for the start of a total lunar eclipse. Diurnal cloudiness driving southeast from IA is expected to further break up and dissipate over the next few hours. Temps continue to be on track with current forecast, supporting continuation of Freeze Warnings with widespread mins in the mid to upper 20s. Note that our forecast will either set or approach current record low temps. See CLIMATE section below. TES && .SHORT TERM: (Through Late Tonight) Issued at 324 PM CDT Mon Apr 14 2014 Main concerns deal with the band of snow currently extending from near Pittsfield to Rolla as well as the going freeze warning. The band has been reducing visibilities to as low as 1/2 mile with some reports of accumulation on grassy surfaces. It is being caused by mid level frontogenesis ahead of the 500mb trough that will move through the area tonight. The RAP and HRRR does show the frotogenesis weakening as it moves acrosss the CWA, but do think that it will likely maintain itself the next few hours before it weakens by early evening. Have extrapolated the band through CWA through early evening, with little or no accumulation of snow expected given the warm low level and surface temperatures. The precipitation and clouds will clear out quick as subsidence moves in behind the passage of the upper trough. With cold air advection and dry dewpoints, expect temperatures to drop quickly to near MOS temperatures. Going freeze warning looks good and plan no changes to it. Britt .LONG TERM: (Tuesday through Next Monday) Issued at 324 PM CDT Mon Apr 14 2014 (Tuesday through Thursday) Have kept Tuesday into Thursday dry as the area will remain cut off from any notable moisture from the Gulf and the active storm track stays north of the area. While Tuesday night will not be as cold as tonight, most areas will still be in the lower to mid 30s for lows. (Thursday Night-Next Monday) The ECMWF and GFS are now similar with the amplitude and timing of the mid level trough and attendant cold front that will move across the area on Friday. Will continue with the chance of showers on Thursday night and Friday before subsidence works in behind the trough keeping Friday night and Saturday dry. Then confidence begins to wane late in the weekend as they both develop QPF over the area. The GFS is placing more emphasis on an northern stream upper over the Upper Midwest while ECMWF is placing it`s emphasis on a shortwave coming out of the southwest CONUS. Either way, will continue the chance of showers we have going Saturday night into Sunday night. Temperatures during the period look to be near or slightly below normal. Britt && .AVIATION: (For the 06z TAFs through 06z Tuesday Night) Issued at 1136 PM CDT Mon Apr 14 2014 Skies have cleared out of taf sites, so clear skies and northwest winds to persist overnight. Will see some diurnal cu develop by midday on Tuesday with winds gradually backing to the southwest then south as surface ridge moves to the east. Specifics for KSTL: Skies have cleared out of taf sites, so clear skies and northwest winds to persist overnight. Will see some diurnal cu develop by 18z Tuesday with winds gradually backing to the southwest then south by 01z Wednesday as surface ridge moves to the east. Byrd && .CLIMATE: RECORD LOWS FOR 4/15: STL - 27 IN 1928 COU - 25 IN 1928 UIN - 24 IN 1928 FAM - 24 IN 1928 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FREEZE WARNING until 9 AM CDT Tuesday FOR Audrain MO-Boone MO- Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO- Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...FREEZE WARNING until 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL- Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL- Pike IL-Randolph IL-St. Clair IL-Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
404 AM EDT TUE APR 15 2014 .SYNOPSIS... A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA TODAY. MUCH COLDER AIR WILL FOLLOW THIS FRONT WITH A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY THIS EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD...WITH MILDER WEATHER RETURNING BY LATE THIS WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... SCATTERED SHRA WERE DEVELOPING IN ADVANCE OF THE SHARP COLD FRONT THAT WILL MOVE ACRS CENTRAL NY AND NORTHEAST PA BETWEEN 11Z AND 19Z FROM NW TO SE. MOST OF THESE SHRA WILL BE VFR WITH PATCHY AREAS OF MVFR IN THE HEAVIEST SHRA. THE COLD FRONT W/ A SHARP WIND SHIFT FROM S TO NW REACHES SYR-PEO BY 12Z TO 13Z...UCA-ELM BY 14Z...KITH BY 15Z...KBGM BY 16Z...AND KAVP BY 19Z. FOR A FEW HOURS AFTER FRONTAL PASSAGE CIGS AND VSBYS WILL DROP TO IFR WITH RA AND BR...THEN THE PRECIP WILL BECOME A MIX OF SNOW/PL AND RAIN WITH A VERY SHARP LOW-LEVEL INVERSION. THERE CUD BE LOW-LEVEL WIND SHEAR AT THE POINT IN THE INVERSION LAYER WHICH WILL BE FAIRLY LOW. THUS LLWS REMAINS IN ALL TAFS TO ACCOUNT FOR A FEW HOUR WINDOW THIS AFTERNOON. AS THE COLD AIR LAYER DEEPENS VERTICALLY THE SHEAR WILL LESSEN TWD EVE. IN CONJUNCTION WITH THIS DEEPENING COLD LAYER...THE PRECIP WILL TURN TO ALL SNOW. I EXPECT MAINLY IFR CIG AND VSBY IN SNOW AND BR FOR A FEW HOURS. THEN CONDITIONS WILL IMPROVE TO MAINLY MVFR TO VFR CIG AND VSBY IN -SHSN MOSTLY AFTER 00Z. WINDS WILL BE MAINLY S-SE ARND 10 KNOTS WITH OCCASIONAL GUST TO 20 KNOTS...THEN THE WINDS WILL SHIFT TO THE NW AFTER FROPA AN AVERAGE 10 TO 20 KNOTS GUSTS TO 25 KTS OR MORE. WINDS CUD GET EVEN STRONGER TWD 00Z. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS THROUGH WEDNESDAY. && .HYDROLOGY... AT THIS TIME LATEST TOTAL PRECIPITATION FORECASTS ARE FOR 1.5 INCHES TO 1.75 INCHES MAINLY EAST OF THE I-81 CORRIDOR AND LESS THAN 1.5 INCHES TO THE WEST. THE COMPLICATING FACTOR IS THAT THE TAIL OF END OF THIS PRECIPITATION LIKELY WILL BE IN THE FORM OF SNOW. OF CONCERN IS THAT A LOT OF THIS RAIN COULD FALL IN A FAIRLY SHORT PERIOD OF TIME INCREASING THE THREAT FOR SOME FLOOD ISSUES ON SMALLER STREAMS...AND ESPECIALLY URBAN AND POOR DRAINAGE AREAS. AS OF EARLY THIS MORNING...FLOOD WATCHES AND WARNINGS REMAIN IN EFFECT FOR ONEIDA COUNTY WHERE WE ARE WATCHING THE WEST CANADA CREEK CLOSELY. THE WEST CANADA CREEK WAS AT 1226.26 FEET AS OF 245 AM EDT AND STILL RISING AT A STEADY CLIP. A FLOOD WARNING IS IN EFFECT FOR THIS CREEK AS PER NWS ALY. LATEST NERFC FORECAST GUIDANCE BRINGS IT 1228 FEET WHICH IS AT THE MODERATE FLOOD LEVEL. IN ADDTN THERE WILL CONTINUE TO BE THE POTENTIAL FOR SMALLER STREAMS IN ONEIDA COUNTY TO SPILL THEIR BANKS LATER TODAY AS AN ADDITIONAL 1.5 INCHES OF RAIN OR SO WILL BE POSSIBLE. CONCERNED ABT THE SRLY UPSLOPE FLOW THAT COULD ENHANCE RAINFALL AS WELL. FOR NOW THE ONEIDA CREEK AT ONEIDA IS NOT EXPECTED TO FLOOD BUT IF LOCALLY HEAVIER RAIN (MORE THAN 2 INCHES) FALLS IN THAT WATERSHED...FLOODING WILL BE POSSIBLE. THE SAQUOIT CREEK AND ORISKANY CREEKS ALSO WILL HAVE THE POTENTIAL TO FLOOD IF ENOUGH RAIN FALLS IN THESE SMALLER WATERSHEDS. FLASH FLOOD GUIDANCE FOR ONEIDA COUNTY IS BETWEEN 2.0 AND 2.5 INCHES IN A 3 TO 6 HOUR PERIOD. THIS COULD BE A LITTLE HARD TO COME BY...EXCEPT LOCALLY. SO A FLOOD WATCH WILL CONT FOR ONEIDA COUNTY TO COVER THE ELEVATED POTENTIAL FOR FLOOD ISSUES UP THERE. FARTHER SOUTH THERE IS MORE UNCERTAINTY. CURRENT RIVER FORECASTS SHOW NO RIVER FLOODING...EVEN IN THE HEADWATERS. HEADWATER FORECAST GUIDANCE FOR MOST AREAS IS RUNNING AOA 2 INCHES IN 3 TO 6 HOURS EXCEPT AT SHERBURNE WHERE IT IS CLOSER TO 1 INCHES FOR MINOR FLOODING AND 1.5 INCHES FOR MODERATE FLOODING. THIS POINT WILL BEARS WATCHING AND IS AN OUTLIER AMONG ALL OTHER HEADWATER FORECAST POINTS. A FEW HEADWATER POINTS CUD SEE MINOR FLOODING WITH 1.5 INCHES OF RAIN IN 6 HOURS BUT MODERATE FLOODING THRESHOLDS ARE OVER 2 INCHES. SO AFTER COLLABORATION WITH NEIGHBORING NWS OFFICES DECIDED NOT TO ISSUE AN FFA JUST YET. IF A BAND OF HEAVY DEVELOPS LATER THIS MORNING AND HAS 1 INCH PER HOUR OR 2 INCH PER 3 HOUR RAINFALL RATES THE DAY SHIFT CAN ISSUE A SHORT FUSED FLASH FLOOD WATCH AS NECESSARY. WE WILL BE ISSUING AN SPS TO COVER THE POTENTIAL FOR SOME FLOODING OUTSIDE OUR FLOOD WATCH AREA AND HIT THE URBAN...POOR DRAINAGE AND LOW-LYING AREAS THE HARDEST. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR NYZ009-037. && $$ SYNOPSIS...DJN NEAR TERM...BMW SHORT TERM...MSE LONG TERM... AVIATION...DJN FIRE WEATHER...DJN HYDROLOGY...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
200 AM EDT TUE APR 15 2014 .SYNOPSIS... VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY... FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY LATE THIS WEEK. && .NEAR TERM /THROUGH TODAY/... WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT. && .SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/... A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND SLEET. DETAILS ARE GIVEN BELOW. A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION. EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE SEASONABLE FOR JUNE THAN MID-APRIL. A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS. SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE CERTAIN. SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES. SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE. THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA. STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT 850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL ACCUMULATIONS SHOULD BE LIGHT. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL. FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH SLGT CHC/LOW CHC POPS FOR THIS PD. TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL NORMS. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... SCATTERED SHRA WERE DEVELOPING IN ADVANCE OF THE SHARP COLD FRONT THAT WILL MOVE ACRS CENTRAL NY AND NORTHEAST PA BETWEEN 11Z AND 19Z FROM NW TO SE. MOST OF THESE SHRA WILL BE VFR WITH PATCHY AREAS OF MVFR IN THE HEAVIEST SHRA. THE COLD FRONT W/ A SHARP WIND SHIFT FROM S TO NW REACHES SYR-PEO BY 12Z TO 13Z...UCA-ELM BY 14Z...KITH BY 15Z...KBGM BY 16Z...AND KAVP BY 19Z. FOR A FEW HOURS AFTER FRONTAL PASSAGE CIGS AND VSBYS WILL DROP TO IFR WITH RA AND BR...THEN THE PRECIP WILL BECOME A MIX OF SNOW/PL AND RAIN WITH A VERY SHARP LOW-LEVEL INVERSION. THERE CUD BE LOW-LEVEL WIND SHEAR AT THE POINT IN THE INVERSION LAYER WHICH WILL BE FAIRLY LOW. THUS LLWS REMAINS IN ALL TAFS TO ACCOUNT FOR A FEW HOUR WINDOW THIS AFTERNOON. AS THE COLD AIR LAYER DEEPENS VERTICALLY THE SHEAR WILL LESSEN TWD EVE. IN CONJUNCTION WITH THIS DEEPENING COLD LAYER...THE PRECIP WILL TURN TO ALL SNOW. I EXPECT MAINLY IFR CIG AND VSBY IN SNOW AND BR FOR A FEW HOURS. THEN CONDITIONS WILL IMPROVE TO MAINLY MVFR TO VFR CIG AND VSBY IN -SHSN MOSTLY AFTER 00Z. WINDS WILL BE MAINLY S-SE ARND 10 KNOTS WITH OCCASIONAL GUST TO 20 KNOTS...THEN THE WINDS WILL SHIFT TO THE NW AFTER FROPA AN AVERAGE 10 TO 20 KNOTS GUSTS TO 25 KTS OR MORE. WINDS CUD GET EVEN STRONGER TWD 00Z. OUTLOOK... TUE NGT...SCT MVFR IN -SHSN CNTRL NY. WED-THU-FRI...VFR. FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS THROUGH WEDNESDAY. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...FLOOD WATCH FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR NYZ009-037. && $$ SYNOPSIS...MSE NEAR TERM...BMW SHORT TERM...MSE LONG TERM... AVIATION...DJN FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
438 AM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE WEST TODAY AND SLOWLY CROSS THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD IN FROM THE NORTH WEDNESDAY INTO FRIDAY...THEN SLIDE OFFSHORE SATURDAY AS A TROUGH OF LOW PRESSURE DEVELOPS NEAR THE COAST SATURDAY. HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY AND MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 4 AM TUE...STRONG...MOIST SOUTHERLY FLOW CONTINUES AHEAD OF A ROBUST LONG WAVE TROUGH PRESENTLY OVER THE MISS RIVER VALLEY WITH A SFC COLD FRONT ACROSS THE OHIO AND TENN RIVER VALLEYS. SCT- NUMEROUS SHOWERS ARE LIFTING N OFF THE ATLANTIC AND ACROSS COASTAL AREAS EARLY THIS MORNING...MAINLY EAST OF HIGHWAY 17...WITH MORE ISOL SHOWERS ACROSS THE COASTAL PLAIN. FARTHER TO THE WEST...AN AREA OF CONVECTION IS CURRENTLY LIFTING ACROSS UPSTATE SC INTO THE WESTERN NC PIEDMONT. HRRR KEEPS THESE STORMS WEST OF THE AREA EARLY THIS MORNING...BUT MESO MODELS LIFT AN AREA OF DIFF VORT ADVECTION ACROSS THE AREA AFTER DAYBREAK AND ENHANCE COVERAGE OF SHOWERS ACROSS EASTERN NC. INSTABILITY INCREASES AFTER DAYBREAK AS WELL BRINGING INCREASING CONVECTIVE CHANCES. MODELS HAVE LI`S INCREASING TO AROUND -2 TO -4 C AND CAPE AROUND 1000-1500 J/KG THIS AFTERNOON WITH 0-6KM BULK SHEAR INCREASING TO 40-60 KT AHEAD OF THE FRONT. THE SHEAR IS MAINLY UNIDIRECTIONAL SUGGESTING DAMAGING WINDS AS THE MAIN THREAT OF SEVERE...WITH THE BEST CHANCE FOR SEVERE STORMS FROM MID AFTERNOON TO MID EVENING ASSOC WITH STRONG FRONTAL FORCING. STRONG SLY FLOW PERSISTS TODAY WITH WIND GUSTS AROUND 25-35 MPH. MOVED THE START TIME OF THE WIND ADVISORY FOR THE OBX AND CARTERET CO TO 4 PM AS MODELS SHOWING SLY WINDS INCREASING TO ADVISORY CRITERIA JUST AHEAD OF THE FRONT. A VERY MILD START THIS MORNING WITH TEMPS AROUND 70 AND DEWPOINT TEMPS IN THE MID TO UPPER 60. MAINLY CLOUDY SKIES WILL KEEP SHORT THERMOMETER WITH HIGH EXPECTED IN THE UPPER 70S INLAND AND LOW TO MID 70S ALONG THE COAST. && .SHORT TERM /TONIGHT/... AS OF 4 AM TUE...THE AFOREMENTIONED COLD FRONT PROGGED TO BE MOVING ACROSS THE COASTAL PLAIN AT THE START OF THE SHORT TERM PERIOD WITH AN ON-GOING SEVERE THREAT ASSOC WITH STRONG FRONTAL FORCING IN A MOIST AND UNSTABLE ENVIRONMENT. HOWEVER THE FRONT IS EXPECTED TO BE PUSHING OFF THE COAST BETWEEN 00Z-02Z WITH THE SEVERE THREAT QUICKLY ENDING AFTER FROPA. STRONG CAA DEVELOPS BEHIND THE FRONT BRINGING NLY WINDS AROUND 15-25 MPH INLAND TO 25-35 MPH WITH HIGHER GUST ALONG THE OBX AND WILL CONTINUE THE WIND ADVISORY INTO WEDNESDAY. THIS COULD BRING MINOR COASTAL FLOODING ISSUES ACROSS THE OBX AND SOUTHERN PAMLICO SOUND AREAS AS WELL...SEE BELOW FOR DISCUSSION. TEMPS EXPECTED TO FALL INTO THE UPPER 30S INLAND TO MID 40S ALONG THE COAST BY DAYBREAK WEDNESDAY. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 225 AM TUE...MODELS IN DECENT AGREEMENT AT THE START OF THE EXTENDED FORECAST PERIODS WITH NEARLY ZONAL FLOW BEHIND EXITING TROUGH OVER THE SOUTHEAST. WILL SEE SOME DIFFERENCES STARTING THURSDAY AS ECMWF SPINS UP A LOW OFFSHORE AND GFSENSEMBLE MAINTAINS A TROUGH. THIS COULD EFFECT SURFACE WIND SPEED ALONG THE COASTAL SECTIONS THROUGH THE END OF THE WORKWEEK. THIS DEEPER LOW PRESSURE IS SUPPORTED BY WEAK UPPER LEVEL ENERGY NOTED IN ECMWF. DIFFERENCES BECOME MORE SIGNIFICANT BY THE WEEKEND AS ECMWF DROPS A DEEP TROUGH INTO FLORIDA WHILE THE GFS NOTES A WEAKER UPPER TROUGH. THIS AGAIN AFFECTS THE SURFACE PATTERN WITH ECMWF DEVELOPING A DEEP SURFACE LOW PRESSURE OFF THE FLORIDA COAST AND GFS KEEPING AN INVERTED TROUGH OFFSHORE. CURRENT GFS IS TRENDING SOMEWHAT DEEPER WITH WEEKEND TROUGH THAN PREVIOUS RUN. NEARLY ZONAL FLOW AT THE BEGINNING OF THE FORECAST PERIOD WILL BECOME SOUTHWESTERLY AS TROUGH DIGS INTO THE CENTRAL PLAINS STATES. WEAK UPPER LEVEL IMPULSES WILL MOVE THROUGH THE SOUTHWEST FLOW THROUGH THE REMAINDER OF THE WORK WEEK. AT THE SURFACE HIGH PRESSURE WILL BUILD INTO CENTRAL PART OF NORTH CAROLINA WITH LOW PRESSURE DEVELOPING OFFSHORE. COASTAL SECTIONS WILL HAVE BREEZY CONDITIONS WITH A SMALL CHANCE OF SHOWERS...DEPENDING ON STRENGTH AND PLACEMENT OF LOW PRESSURE OFFSHORE. THE STRONG NORTHERLY FLOW WILL KEEP TEMPERATURES BELOW NORMAL WITH LOW TEMPERATURES IN THE MID 30S TO LOWER 40S AND HIGH TEMPERATURES IN THE 50S WEDNESDAY. THIS PATTERN WILL REMAIN THROUGH THE WORKWEEK WITH RISING HEIGHTS ALLOW TEMPERATURES TO RISE INTO THE UPPER 50S TO LOWER 60S. BY SATURDAY UPPER TROUGH WILL MOVE ACROSS THE EAST COAST WITH LOW PRESSURE DEVELOPING OFF THE FLORIDA COAST...ACCORDING TO ECMWF. DUE TO UNCERTAINTY IN THIS TIME PERIOD...WONT MAKE ANY CHANGES TO THE GRIDS. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... SHORT TERM /THROUGH TONIGHT/... AS OF 4 AM TUE...GENERALLY MVFR CONDITIONS EXPECTED INTO MID AFTERNOON WITH SCT SHOWERS ACROSS RTES AHEAD OF A STRONG COLD FRONT. COULD SEE A FEW THUNDERSTORMS THIS MORNING WITH INCREASING INSTABILITY. STRONG SLY WINDS AROUND 15-20 KT WITH GUSTS AROUND 25 KT TODAY. BY MID TO LATE AFTERNOON THE FRONT WILL BE PUSHING INTO RTES BRINGING STRONG FRONTAL FORCING AND THE CHANCE FOR STRONG TO SEVERE THUNDERSTORMS AND CONDITIONS AOB IFR. WINDS BECOME NLY AFTER FROPA WITH STRONG CAA DEVELOPING AND COULD SEE GUSTS AROUND 30 KT DURING EVENING...BUT WILL SEE CLEARING SKIES WITH VFR CONDITIONS RETURNING LATE EVENING AND AFTER MIDNIGHT. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 231 AM TUE...VFR CONDITIONS WILL PREDOMINATE THROUGH FRIDAY WITH HIGH PRESSURE BUILDING IN THE CENTRAL PART OF NORTH CAROLINA. MAIN PROBLEM WILL BE WIND WITH NORTHERLY FLOW GUSTING TO 25 KT ON WEDNESDAY...STRONGEST NEARER THE COAST. MODELS TRENDING DRIER THAN PREVIOUS RUNS...BUT MAY SEE SOME SUB VFR CONDITIONS SATURDAY WITH ISOLATED SHOWERS. && .MARINE... SHORT TERM /THROUGH TUESDAY/... AS OF 4 AM TUE...MARINE OBS SHOWING SLY WINDS AROUND 15-25 KT WITH SEAS AROUND 4-7 FT MOST AREAS...BUT UP TO 9 FT OFFSHORE ONSLOW BAY. WINDS INCREASE TO 20-30 KT TODAY AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST WITH SEAS BUILDING TO 7-11 FT. FREQUENT GUSTS TO GALE FORCE LIKELY ACROSS THE CENTRAL WATERS WITH BETTER MIXING HERE AND MOVED START TIME OF THE GALE WARNING TO 18Z HERE. THE COLD FRONT WILL CROSS THE WATERS THIS EVENING WITH STRONG NLY FLOW TO GALE FORCE DEVELOPING MOST AREAS...LIKELY JUST BELOW GALE FOR THE PAMLICO AND NEUSE RIVER ZONES. SEAS BUILD TO 10-15 FT NRN WATERS AFTER MIDNIGHT AND REMAIN AROUND 6-10 FT SOUTHERN WATERS. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 236 AM TUE...STRONG NORTHERLY FLOW WILL START THE PERIOD ON WEDNESDAY BEHIND DEPARTING COLD FRONT. GALE FORCE SPEEDS EXPECTED THROUGH MUCH OF THE DAY ON WEDNESDAY WITH TIGHT GRADIENT BETWEEN THE FRONT AND HIGH PRESSURE BUILDING INTO THE CENTER PART OF THE STATE. GRADIENT WILL LOOSEN WEDNESDAY AFTERNOON/EVENING...BUT SPEEDS EXPECTED TO REMAIN IN THE 20 KN RANGE THURSDAY. SOME DIFFERENCES IN MODELS BY THE END OF THE WEEK AND INTO THE WEEKEND WITH STRENGTH OF LOW PRESSURE/TROUGH OFFSHORE DETERMINING SPEEDS OVER THE WATERS. FOR NOW WILL STAY WITH 15 TO 20 KTS. && .TIDES/COASTAL FLOODING... ELEVATED WATER LEVELS CAN BE EXPECT AS A STRONG N/NE FLOW DEVELOPS BEHIND A SHARP COLD FRONT LATE TUESDAY NIGHT AND EARLY WEDNESDAY. THE STRONG WINDS COINCIDE WITH A HIGH ASTRONOMICAL CYCLE COMING OUT OF THIS EARLY WEEKS FULL MOON. NW GALES GRADUALLY SHIFTING TO N TONIGHT AND WEDNESDAY SUGGEST HIGHEST WATER LEVELS...AROUND 2-3 FT TIDAL ANOMALIES FOR THE CENTRAL AND SOUTHERN OBX ADJACENT TO THE PAMLICO SOUND BASED ON COASTAL FLOOD CLIMATOLOGY. CERA WEBSITE KEEPS MAX WATER LEVELS ANOMALIES BETWEEN 1.5-2 FT BUT FEEL IT COULD BE A LITTLE HIGHER WITH MINOR IMPACTS AND WILL ISSUE A COASTAL FLOOD ADVISORY FOR OBX DARE AND HYDE WITH THE MORNING PACKAGE. WINDS DO NOT SHIFT TO NE UNTIL WED AFTERNOON AND ARE DECREASING BELOW GALES AS THEY DO...SO AT THIS TIME THINK THE SOUTHERN PAMLICO SOUND AND NEUSE/PAMLICO RIVER AREAS WILL HAVE LESS OF AN IMPACT. THE HIGH WATER LEVELS WILL ONLY SLOWLY SUBSIDE AS A MODERATE NNE FLOW IS MAINTAINED BETWEEN STRONG HIGH PRES TO THE NORTH AND OFFSHORE LOW PRESSURE TROF THRU THE END OF THE WEEK. && NC...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 5 PM EDT WEDNESDAY FOR NCZ095-103-104. COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO 8 PM EDT WEDNESDAY FOR NCZ103-104. MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 5 PM EDT WEDNESDAY FOR AMZ136-137. GALE WARNING FROM 8 PM THIS EVENING TO 5 PM EDT WEDNESDAY FOR AMZ130-131-135-150. GALE WARNING FROM 2 PM THIS AFTERNOON TO 5 PM EDT WEDNESDAY FOR AMZ152-154. GALE WARNING FROM 8 PM THIS EVENING TO 4 PM EDT WEDNESDAY FOR AMZ156-158. && $$ SYNOPSIS...SK NEAR TERM...SK SHORT TERM...SK LONG TERM...CGG AVIATION...CGG/SK MARINE...CGG/SK TIDES/COASTAL FLOODING...SK/BTC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
303 AM EDT TUE APR 15 2014 .SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST AHEAD OF A COLD FRONT THAT WILL CROSS THE CAROLINAS THIS AFTERNOON AND EVENING. UNSEASONABLY STRONG AND COOL HIGH PRESSURE WILL THEN BUILD EAST ACROSS THE MIDDLE ATLANTIC REGION TONIGHT THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1015 PM MONDAY... WARM MOIST AIR CONTINUES TO FILTER INTO CENTRAL NC THIS EVENING WITH DEWPOINTS INCREASING INTO THE LOWER TO MID 60S AS SOUTH TO SOUTHEASTERLY FLOW IS INCREASING IN ADVANCE OF A STRONG COLD FRONT... CURRENTLY EXTENDING FROM THE EASTERN GREAT LAKES REGION SOUTH-SOUTHWESTWARD TO THE AROUND NEW ORLEANS. THIS FRONT WILL CONTINUE PUSHING EASTWARD OVERNIGHT... APPROACHING THE CENTRAL TO SOUTHERN APPALACHIANS BY 12Z TUESDAY. THE WEAK PRE-FRONTAL BAND OF CONVECTION THAT MOVED ACROSS TN/GA/SC AND WESTERN NC EARLIER TODAY WEAKENED FURTHER THIS EVENING AND HAS LEFT AN OUTFLOW BOUNDARY ACROSS PORTIONS OF THE WESTERN PIEDMONT. NEW SHOWERS AND STORMS ARE NOW FORMING ON THE BOUNDARY. INSTABILITY IS INCREASE ACROSS THE AREA IN GENERAL... WITH A NOSE OF MLCAPE (SMALL AMOUNT 100-250 J/KG) EXTENDING UP TOWARDS THE DAVIDSON/ROWAN COUNTY LINE. THIS COUPLE WITH STRONG DEEP LAYER SHEAR (0-6 KM SHEAR OF AROUND 40-50 KTS) AND A FAVORABLE LOW LEVEL WIND PROFILE (0-1KM SRH OF 150-200 M2/S2) HAS YIELDED SOME WEAK ROTATION WITH THESE VERY SHALLOW SHOWERS/STORMS FROM TIME TO TIME. AT THIS TIME DO NOT THINK ANY WEAK ROTATION WILL RESULT IN ANY ISOLATED BRIEF TORNADOES AS THE UPDRAFTS DO NO APPEAR STRONG ENOUGH. THAT SAID... WE WILL NEED TO KEEP AN EYE ON THE RADAR FOR ANY QUICK SPIKE IN INTENSITY WITH THESE SHOWERS/STORMS SINCE THEY ARE INVOF THE REMNANT OUTFLOW BOUNDARY FROM EARLIER. GIVEN THE ABOVE MENTIONED DEEP SHEAR AND FAVORABLE ATLANTIC LOW LEVEL SOUTHEASTERLY INFLOW WE WILL NEED TO WATCH ANY CONVECTION THAT FORMS OVER THE AREA OVERNIGHT... ESPECIALLY WITH THE LATEST RAP SHOWING AS MUCH AS 500 J/KG OF MLCAPE MOVING INTO OUR SOUTH/SOUTHEASTERN HALF OF CENTRAL NC OVERNIGHT. LATEST HRRR AND RAP SHOW AN INCREASE IN ACTIVITY AFTER 06Z TONIGHT. THUS... WILL MAINTAIN HIGH POPS AFTER 06Z TONIGHT AND MAINTAIN MENTION OF SOME STRONG WIND GUSTS. EXPECT OVERNIGHT LOWS WILL BE WARM GIVEN THE INCREASING MOISTURE/CLOUD COVER. THUS... EXPECT LOW TEMPS WILL BE IN THE LOWER TO MID 60S. TUE-TUE NIGHT: WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID- MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40- 50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100- 300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST. STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING... KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32 MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 235 AM TUESDAY... WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE) WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900 MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER- ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE 50S. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE 20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO 33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER... GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 300 AM TUESDAY... THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50 DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 200 AM TUESDAY... 24 HOUR TAF PERIOD: MVFR/IFR CONDITIONS ACROSS THE AREA WILL LIKELY DECREASE FURTHER INTO IFR/LIFR BY DAYBREAK TUESDAY. HEAVY SHOWERS AND THUNDERSTORMS ARE APPROACHING FROM THE SOUTHWEST...ALREADY IMPACTING KINT AND KGSO...AND LIKELY MOVING OVER KFAY AND KRDU OVER THE NEXT COUPLE HOURS (AND KRWI THEREAFTER). THOUGH IT IS POSSIBLE THE CIGS MAY IMPROVE SLIGHTLY WITH THESE HEAVY SHOWERS...VISBYS WILL LIKELY DECREASE. AS ALREADY SEEN AT KINT AND KGSO...SOUTHWEST WINDS WILL BECOME GUSTY (20-25 KTS) AS THE LOW LEVEL FLOW STRENGTHENS. IF THERE IS A BREAK IN THE PRECIP TUESDAY MORNING...CONDITIONS MAY IMPROVE BACK TO MVFR...BUT EXPECT MORE SHOWERS AND THUNDERSTORMS TO MOVE ACROSS THE AREA AHEAD OF THE COLD FRONT...EXPECTED TO MOVE FROM WEST TO EAST THROUGH CENTRAL NC DURING THE LATE AFTERNOON/EARLY EVENING. ALTHOUGH WINDS WILL REMAIN STRONG AND GUSTY THROUGH THE TAF PERIOD...EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE FRONT. CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT... WITH VFR CONDITIONS EXPECTED BY THE END OF THE PERIOD. -KC LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ007>010-021>026-038>041-073>077-083-084. && $$ SYNOPSIS...MWS NEAR TERM...BSD/DJF SHORT TERM...MWS/KCP LONG TERM...KCP AVIATION...KCP/KRD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
254 AM EDT TUE APR 15 2014 .SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST AHEAD OF A COLD FRONT THAT WILL CROSS THE CAROLINAS THIS AFTERNOON AND EVENING. UNSEASONABLY STRONG AND COOL HIGH PRESSURE WILL THEN BUILD EAST ACROSS THE MIDDLE ATLANTIC REGION TONIGHT THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1015 PM MONDAY... WARM MOIST AIR CONTINUES TO FILTER INTO CENTRAL NC THIS EVENING WITH DEWPOINTS INCREASING INTO THE LOWER TO MID 60S AS SOUTH TO SOUTHEASTERLY FLOW IS INCREASING IN ADVANCE OF A STRONG COLD FRONT... CURRENTLY EXTENDING FROM THE EASTERN GREAT LAKES REGION SOUTH-SOUTHWESTWARD TO THE AROUND NEW ORLEANS. THIS FRONT WILL CONTINUE PUSHING EASTWARD OVERNIGHT... APPROACHING THE CENTRAL TO SOUTHERN APPALACHIANS BY 12Z TUESDAY. THE WEAK PRE-FRONTAL BAND OF CONVECTION THAT MOVED ACROSS TN/GA/SC AND WESTERN NC EARLIER TODAY WEAKENED FURTHER THIS EVENING AND HAS LEFT AN OUTFLOW BOUNDARY ACROSS PORTIONS OF THE WESTERN PIEDMONT. NEW SHOWERS AND STORMS ARE NOW FORMING ON THE BOUNDARY. INSTABILITY IS INCREASE ACROSS THE AREA IN GENERAL... WITH A NOSE OF MLCAPE (SMALL AMOUNT 100-250 J/KG) EXTENDING UP TOWARDS THE DAVIDSON/ROWAN COUNTY LINE. THIS COUPLE WITH STRONG DEEP LAYER SHEAR (0-6 KM SHEAR OF AROUND 40-50 KTS) AND A FAVORABLE LOW LEVEL WIND PROFILE (0-1KM SRH OF 150-200 M2/S2) HAS YIELDED SOME WEAK ROTATION WITH THESE VERY SHALLOW SHOWERS/STORMS FROM TIME TO TIME. AT THIS TIME DO NOT THINK ANY WEAK ROTATION WILL RESULT IN ANY ISOLATED BRIEF TORNADOES AS THE UPDRAFTS DO NO APPEAR STRONG ENOUGH. THAT SAID... WE WILL NEED TO KEEP AN EYE ON THE RADAR FOR ANY QUICK SPIKE IN INTENSITY WITH THESE SHOWERS/STORMS SINCE THEY ARE INVOF THE REMNANT OUTFLOW BOUNDARY FROM EARLIER. GIVEN THE ABOVE MENTIONED DEEP SHEAR AND FAVORABLE ATLANTIC LOW LEVEL SOUTHEASTERLY INFLOW WE WILL NEED TO WATCH ANY CONVECTION THAT FORMS OVER THE AREA OVERNIGHT... ESPECIALLY WITH THE LATEST RAP SHOWING AS MUCH AS 500 J/KG OF MLCAPE MOVING INTO OUR SOUTH/SOUTHEASTERN HALF OF CENTRAL NC OVERNIGHT. LATEST HRRR AND RAP SHOW AN INCREASE IN ACTIVITY AFTER 06Z TONIGHT. THUS... WILL MAINTAIN HIGH POPS AFTER 06Z TONIGHT AND MAINTAIN MENTION OF SOME STRONG WIND GUSTS. EXPECT OVERNIGHT LOWS WILL BE WARM GIVEN THE INCREASING MOISTURE/CLOUD COVER. THUS... EXPECT LOW TEMPS WILL BE IN THE LOWER TO MID 60S. TUE-TUE NIGHT: WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID- MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40- 50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100- 300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST. STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING... KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32 MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 235 AM TUESDAY... WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE) WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900 MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER- ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE 50S. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE 20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO 33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER... GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE. WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED. EXPECT TEMPS CLOSE TO NORMAL MON. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 200 AM TUESDAY... 24 HOUR TAF PERIOD: MVFR/IFR CONDITIONS ACROSS THE AREA WILL LIKELY DECREASE FURTHER INTO IFR/LIFR BY DAYBREAK TUESDAY. HEAVY SHOWERS AND THUNDERSTORMS ARE APPROACHING FROM THE SOUTHWEST...ALREADY IMPACTING KINT AND KGSO...AND LIKELY MOVING OVER KFAY AND KRDU OVER THE NEXT COUPLE HOURS (AND KRWI THEREAFTER). THOUGH IT IS POSSIBLE THE CIGS MAY IMPROVE SLIGHTLY WITH THESE HEAVY SHOWERS...VISBYS WILL LIKELY DECREASE. AS ALREADY SEEN AT KINT AND KGSO...SOUTHWEST WINDS WILL BECOME GUSTY (20-25 KTS) AS THE LOW LEVEL FLOW STRENGTHENS. IF THERE IS A BREAK IN THE PRECIP TUESDAY MORNING...CONDITIONS MAY IMPROVE BACK TO MVFR...BUT EXPECT MORE SHOWERS AND THUNDERSTORMS TO MOVE ACROSS THE AREA AHEAD OF THE COLD FRONT...EXPECTED TO MOVE FROM WEST TO EAST THROUGH CENTRAL NC DURING THE LATE AFTERNOON/EARLY EVENING. ALTHOUGH WINDS WILL REMAIN STRONG AND GUSTY THROUGH THE TAF PERIOD...EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE FRONT. CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT... WITH VFR CONDITIONS EXPECTED BY THE END OF THE PERIOD. -KC LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR NCZ007>010-021>026-038>041-073>077-083-084. && $$ SYNOPSIS...MWS NEAR TERM...BSD/DJF SHORT TERM...MWS/KCP LONG TERM...HARTFIELD AVIATION...KC/KRD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
203 AM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH THE AREA FROM THE WEST LATE TONIGHT AND PASS ACROSS THE REGION DURING TUESDAY RESULTING IN WIDESPREAD SHOWERS. MUCH COLDER AIR WILL RUSH IN BEHIND THE FRONT TUESDAY AFTERNOON AS UNSEASONABLY COLD HIGH PRESSURE BEGINS TO BUILD IN ON STRONG NORTHWEST WINDS INTO TUESDAY NIGHT. THE HIGH WILL BUILD OVER THE MID ATLANTIC REGION WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 830 PM EDT MONDAY... SHOWERS HAVE BEEN SLOW TO EVOLVE THIS EVENING WITH MOSTLY LIGHT RAINFALL SEEN ACROSS THE SRN BLUE RIDGE ATTM DESPITE INCREASING MOISTURE OFF EVENING SOUNDINGS. MODELS REMAIN OVERDONE WITH DEGREE OF LIFT UNDER PASSING SHORTWAVES WELL AHEAD OF THE MAIN UPPER TROF THIS EVENING AS THE FLOW REMAINS MORE SW AND FORCING WEAK. LATEST HRRR SEEMS TO HAVE A HANDLE ON LIGHTER SHRA FOR A WHILE LONGER BEFORE THE FLOW DEEPENS/BACKS AND BETTER ISENTROPIC LIFT KICKS IN WITH AN INCREASING SOUTHERLY JET ESPCLY AFTER MIDNIGHT. HAVE ALREADY UPDATED TO LOWER POPS THIS EVENING...THEN QUICKLY REBOUND TO CATEGORICAL MOST SECTIONS OVERNIGHT AS BANDS OF SHRA BEGIN TO LIFT NORTH AHEAD OF THE WAVE AS WEAK INSTABILITY SHIFTS NORTH ACROSS SOUTHERN/EASTERN SECTIONS LATE. GIVEN THIS ALONG WITH STRONGER WIND FIELDS INCLUDED A LOW TOPPED TSRA MENTION ESPCLY FAR WEST JUST AHEAD OF THE FRONT AROUND DAWN AND OUT EAST FOR LOW TOPPED BANDS LATE AS WELL. BUMPED UP LOWS A LITTLE OUT WEST AS EXPECT THE FRONT TO BE JUST SLOW ENOUGH TO KEEP MOST TEMP FALLS FROM OCCURRING UNTIL THE MORNING. OTRW A MILD NIGHT WITH LOWS 50S TO LOWER 60S. WINDS AND LOW TOPPED SHRA THE MAIN CONCERNS DURING TUESDAY WITH STRONG ENOUGH GUSTS TO SUPPORT AT LEAST AN ADVISORY BLUE RIDGE SECTIONS WITH POSSIBLE BANDED SHRA OUT EAST DESPITE LIMITED INSTABILITY. AFTER COORDINATION WITH OTHER OFFICES HAVE DECIDED TO GIVE THE MIDSHIFT ANOTHER LOOK RATHER THAN HOISTING A WIND ADVISORY TONIGHT AS MAY BE CLOSE TO WARNING CRITERIA OVER THE SW FOR A PERIOD TUESDAY AFTERNOON. OTRW MADE SOME ADJUSTS TO TIMING OF THE HEAVIER SHRA AND POSSIBLE ISOLATED TSRA TUESDAY. PREVIOUS DISCUSSION AS OF 320 PM EDT MONDAY... SHOWERS STARTING TO ENTER THE WRN CWA THIS AFTERNOON. 12Z MODELS AND LATEST LOCAL HIGH-RES FAVOR SLOWER TIMING TO THE EAST THRU DUSK...BUT BY MIDNIGHT MOST AREAS WILL SEE LIKELY TO CATEGORICAL POPS AS SERIES OF UPPER VORTS MOVING AHEAD OF THE FRONT SHIFT FROM THE GULF COAST STATES INTO VA. APPEARS THUNDER THREAT WILL STAY ISOLATED AT BEST GIVEN INSTABILITY IS WEAK. GOOD JET DYNAMICS WILL LEAD TO POCKETS OF HEAVY RAIN OVERNIGHT INTO TUESDAY...AS FRONT APPROACHES. MODELS IN AGREEMENT EASING THE FRONT INTO THE MOUNTAINS BY 12Z-15Z TUESDAY AND SHIFTING TO THE EAST OF THE FORECAST AREA BY LATE TUE AFTERNOON. DESPITE FRONT MOVING THROUGH APPEARS ENOUGH LIFT AROUND THE BACKSIDE WITH SOUTHERLY JET TO KEEP THREAT OF RAIN WELL INTO TUESDAY AFTERNOON. RUSH OF COLDER AIR WORKS IN ABOUT 2-4 HOURS BEHIND THE FRONT CHANGING ANY LINGERING PRECIP TO SNOW SHOWERS IN THE HIGHER ELEVATIONS. GIVEN WARMER GROUND THE SNOW AMOUNTS THROUGH TOMORROW WILL BE LESS THAN AN INCH OVER THE RIDGETOPS ABOVE 3000 FT. WILL HAVE TO WATCH FOR ISOLATED FLOODING GIVEN WAVES OF LOW PRESSURE ALONG THE FRONT AND POTENTIAL FOR SOME TRAINING...ALTHOUGH SPEED OF FRONT MAY HINDER IT SOME. STILL QPF LOOKING ON THE ORDER OF 1 TO 1.5 INCHES...THOUGH LOCALLY HIGHER SEEMS LIKELY IN HEAVIER DOWNPOURS. WILL HOLD OFF ON ANY FLOOD WATCHES. EVEN THE RIVER ENSEMBLE FORECASTS ARE NOT TAKING ANY RIVER STAGES ABOVE FLOOD STAGE. WILL HAVE TO WATCH SOUTH BOSTON ON THE DAN THOUGH...GIVEN AMOUNTS SEEM SIMILAR TO LAST WEEK. THE OTHER ISSUE SHOULD BE WINDS BEHIND THE FRONT AS 6 HR PRESSURE RISES ON THE ORDER OF 6 TO 12 MB ARE EXPECTED. MADE SOME ADJUSTMENTS UP IN WIND GUSTS TO 40 KNOTS ACROSS THE SRN BLUE RIDGE AND ADJACENT AREAS. WILL ALLOW FOR ONE MORE RUN OF THE MODELS AS CLOUD COVER WILL TEMPER SOME OF THE GUSTS ABOVE INVERSION. HWO WILL MENTION WIND ADVISORY POTENTIAL. AS FOR TEMPS WILL BE SEEING SLOW FALLING AT BEST OVERNIGHT WITH CONTINUED SOUTH FLOW...WITH SHOWERS HELPING TO COOL IT SOME. TOMORROW WILL BE MILD IN THE FAR EAST BUT TEMPS WILL BE FALLING TO THE FREEZING MARK INTO THE UPPER 30S ACROSS THE MOUNTAINS BY DUSK. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AS OF 355 PM EDT MONDAY... H85 TEMPS PLUNGE BEHIND STRONG COLD FRONT TUESDAY NIGHT...NEARING -12C PER THE GFS. MOISTURE DRIES OUT RATHER QUICKLY ALOFT...BUT SHOULD BE ENOUGH TO GENERATE AN HOUR OR TWO OF UPSLOPE SNOW SHOWERS ACROSS WESTERN GREENBRIER WHERE A QUICK HALF INCH OR LESS MAY FALL ABOVE 2500 FEET. SNOW SHOWERS/FLURRIES MAY FALL FOR A BRIEF TIME DOWN TO BLUEFIELD...BUT NO ACCUMULATION IS EXPECTED. SKIES SHOULD CLEAR RAPIDLY....WITH STRONG DOWNSLOPE...AND H85 JET NEAR 50KTS SHOULD PRODUCE WIND ADVISORY CRITERIA ACROSS NW NC/EXTREME SW VA AT THE VERY LEAST. POSSIBLY A SMALL WINDOW TUESDAY EVENING WITH HIGH WIND CRITERIA GUSTS NW NC. 1030MB HIGH PRESSURE NOSES ACROSS THE MOUNTAINS QUICKLY...AND MOS GUIDANCE IS SOLIDLY AT OR BELOW 32F FOR LOWS WED MORNING EVEN ACROSS THE PIEDMONT/SOUTHSIDE. BECAUSE OF THIS ISSUED A FREEZE WATCH EAST OF THE BLUE RIDGE. WINDS SHOULD HOLD THROUGH MUCH OF THE NIGHT...AND SOMETIMES LOWS COME IN A FEW DEGREES WARMER IN THIS SETUP. THUS THE CHANCE OF A WIDESPREAD FREEZE MAY BE MARGINAL ACROSS THE SOUTHEASTERN CWA...SOUTHSIDE/NC PIEDMONT. MUCH BETTER CHANCE NORTH OF THIS REGION. SURFACE HIGH PRESSURE WEDGING DOWN THE APPALACHIANS IS PRETTY MUCH LOCKED IN THROUGH THURSDAY NIGHT...WITH DRY SUNNY DAYS AND COLD NIGHTS EXPECTED. WITH LESS WIND WEDNESDAY NIGHT AND DEWPOINTS INTO THE TEENS WED PM...CONDS MAY BE EVEN MORE FAVORABLE FOR MORE WIDESPREAD FREEZE...WITH ANOTHER WATCH NECESSARY WED NIGHT/THURS MORNING. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 355 PM EDT MONDAY... WEAK TROUGH THROUGH THE MIDWEST EVENTUALLY PUSHES EAST...AND WEDGING HIGH PRESSURE EVENTUALLY DEPARTS THIS WEEKEND. WITH A RATHER DRY ANTECEDENT AIRMASS...QUESTIONABLE IF THIS MIDWEST TROUGH PRODUCES ANY PRECIP ONCE IT ARRIVES ACROSS THE OHIO VALLEY AND MIDDLE ATLANTIC THIS WEEKEND. OP GFS IS FAR MORE WET THAN THE ECMWF. THUS...POPS WERE KEPT RATHER LOW. A ZONAL UPPER FLOW TAKES SHAPE BY LATE WEEKEND INTO EARLY NEXT WEEK...WITH UNEVENTFUL AND DRY WEATHER CONTINUING ACROSS THE REGION. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 150 AM EDT TUESDAY... MVFR TO IFR CIGS/VSBYS IN AREAS OF RAIN SHOWERS AND FOG EXPECTED THROUGH AROUND 18Z...AT WHICH POINT A STRONG COLD FRONT WILL MOVE THROUGH...IMPROVING CIGS TO VFR AFT 18Z PIEDMONT...BUT WITH CONTINUED MVFR CIGS IN UPSLOPE FLOW AND -SHRA OR EVEN POSSIBLY -SHSN EASTERN WV TAF SITES. BCB WILL SEE PERIODS OF MVFR CIGS CONTINUING THROUGH EVENING. MVFR VSBYS MAY CONTINUE AT BLF FOR A WHILE IN THE AFTERNOON/EARLY EVENING...BUT SHOULD IMPROVE TO VFR AT ALL OTHER SITES BY 20Z. WINDS WILL BE ONE OF THE GREATEST CONCERNS THIS TAF VALID CYCLE...MAINLY BEHIND THE FRONT. AHEAD OF THE FRONT...A GENERAL INCREASE OF SSE-SSW WINDS OF 10-20KTS CAN BE EXPECTED...BUT BEHIND THE FRONT...EXPECT WNW-NW 15-20KTS WITH GUSTS 30-40KTS. IT APPEARS THAT THIS WILL ONLY BE FOR A FEW HOURS...THEN DIMINISHING FAIRLY RAPIDLY AFT 02Z. MEDIUM CONFIDENCE IN CIGS/VSBYS THROUGH THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID PERIOD. LOW CONFIDENCE IN POTENTIAL FOR TSRA ROA/LYH/DAN AND LOW CONFIDENCE FOR -SHSN AT BLF/LWB THROUGH TAF VALIDP PERIOD. EXTENDED AVIATION DISCUSSION... MUCH DRIER AIR WORKS IN BEHIND THE FRONT WEDNESDAY WITH STRONG HIGH PRESSURE WEDGED IN FROM THE NE. THIS SHOULD ALLOW A RETURN TO WIDESPREAD VFR WITH THIS SCENARIO CONTINUING THURSDAY WITH HIGH PRESSURE RIDGING IN FROM OFF NEW ENGLAND AND THE NEXT COLD FRONT TO THE NW. THIS FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW AND WEAK ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. THIS SYSTEM MAY BRING MVFR CIGS TO THE MOUNTAINS SATURDAY ALONG WITH A FEW SHOWERS OTRW VFR ELSW TO START THE WEEKEND. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR VAZ022>024-032>035-043>047-058-059. NC...FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR NCZ003>006-019-020. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH/WP SHORT TERM...KM LONG TERM...KM AVIATION...JH/RAB
AREA FORECAST DISCUSSION
NWS MIAMI FL
950 AM EDT TUE APR 15 2014 .UPDATE... SOMEWHAT OF A FORECAST DILEMMA THIS MORNING CONCERNING THE CHANCE OF AFTERNOON THUNDERSTORMS. A COLD FRONT CURRENTLY IS MOVING ACROSS THE FLORIDA PANHANDLE WITH A BAND OF SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT THROUGH THE BIG BEND AREA AND INTO THE NORTHEAST GULF OF MEXICO. PLENTY OF SUN IS OCCURRING ACROSS SOUTH FLORIDA WHICH WILL PROVIDE SUFFICIENT DIURNAL HEATING TODAY AS THE FRONT APPROACHES CENTRAL FLORIDA LATE THIS AFTERNOON. HOWEVER, HEREIN LIES THE QUESTION. THE 12Z MFL SOUNDING CONTINUES TO SHOW A QUITE STABLE LAYER OF AIR WITH THE BASE AT ABOUT 10K AND EXTENDING UPWARDS TO ABOUT 15K. THIS IS GOING TO BE A INHIBITING FACTOR WITH ANY SHOWER ACTIVITY HAVING A TOUGH TIME BREAKING THROUGH THIS STABLE CAP. HOWEVER, DUE TO THE SUFFICIENT HEATING THAT WILL BE TAKING PLACE AND MAXIMUM AFTERNOON TEMPERATURES APPROACHING THE 90 DEGREE MARK BY 2-3 PM EDT THIS COULD PROVIDE THE NECESSARY BUOYANCY TO PENETRATE THE STABLE LAYER. SOME OF THE HIGH RESOLUTION SHORT TERM COMPUTER MODELS DO SHOW SOME CONVECTIVE DEVELOPMENT AT THAT TIME AND THEN MOVING TOWARDS THE EAST COAST IN THE GENERAL SOUTHWEST STEERING FLOW. STILL, THE HRRR WHICH IS VERY RELIABLE FOR SOUTH FLORIDA ONLY SHOWS ISOLATED DEVELOPMENT AND MAINLY ALONG THE PALM BEACH COASTAL AREA. THE FORTUNATE ASPECT OF THE HRRR IS THAT IT UPDATES EVERY HOUR SO WILL BE TAKING A CLOSE LOOK AT ITS SOLUTIONS OVER THE NEXT SEVERAL HOURS AND MAY NEED TO SCALE BACK POPS AT LEAST OVER THE WESTERN PORTIONS OF THE PENINSULA. KOB && .PREV DISCUSSION... /ISSUED 722 AM EDT TUE APR 15 2014/ SHORT TERM... A COLD FRONT OVER THE FLORIDA PANHANDLE WILL CONTINUE TO MOVE SOUTHWARD DOWN THE SUNSHINE STATE TODAY AND THROUGH SOUTH FLORIDA THIS EVENING. THE WINDS OVER SOUTH FLORIDA TODAY WILL BE FROM SOUTH/SOUTHWEST DIRECTION AHEAD OF THE FRONT ALLOWING TEMPERATURES TO WARM UP INTO THE MID TO UPPER 80S OVER MOST AREAS...EXCEPT AROUND 90 ALONG THE EAST COAST METRO AREAS. AT THE SAME TIME...MOISTURE WILL ALSO BE WORKING INTO SOUTH FLORIDA FROM THE SOUTH LEADING TO SCATTERED SHOWERS AND EVEN SOME THUNDERSTORMS OVER SOUTH FLORIDA THIS AFTERNOON INTO THIS EVENING. ONE OR TWO OF THE STORMS COULD EVEN BECOME STRONG LATE THIS AFTERNOON INTO THIS EVENING MAINLY AROUND THE LAKE OKEECHOBEE REGION AND THE EAST COAST METRO AREAS WHERE PERHAPS BETTER CONVERGENCE WILL BE. THE PRIMARY IMPACTS FROM THE STRONG STORMS WILL BE GUSTY WINDS...AS A LOW LEVEL JET OF 40 TO 50 KNOTS WILL BE MOVING THROUGH THE AREA. SO WILL MENTION THIS IN THE HWO MORNING PACKAGE. DRIER AIR WILL THEN BE WORKING INTO SOUTH FLORIDA FOR LATE TONIGHT. HOWEVER...THE DRY AIR WILL NOT LAST LONG AS THE FRONT WILL STALL OVER THE FLORIDA KEYS LATE TONIGHT BEFORE MOVING BACK NORTHWARD THROUGH SOUTH FLORIDA WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THIS WILL BRING BACK SOME MOISTURE ALONG WITH A CHANCE OF SHOWERS TO THE AREA. SO WILL CONTINUE THE ISOLATED TO SCATTERED SHOWERS OVER SOUTH FLORIDA FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THE LATEST MEDIUM RANGE MODELS ARE NOW SHOWING LOW PRESSURE DEVELOPING OVER THE NORTHERN GULF OF MEXICO LATE THIS WEEK AND MOVING EAST ACROSS NORTH FLORIDA BEFORE MOVING INTO THE WESTERN ATLANTIC WATERS THIS WEEKEND. THIS WILL PUSH THE FRONT BACK SOUTHWARD THROUGH SOUTH FLORIDA FRIDAY NIGHT. SO THE TROPICAL MOISTURE WILL REMAIN IN PLACE FOR LATE THIS WEEK BEFORE DRIER AIR WORKS INTO SOUTH FLORIDA FOR THIS WEEKEND. SO WILL CONTINUE THE SCATTERED POPS OVER SOUTH FLORIDA LATE THIS WEEK ALONG WITH A THREAT OF THUNDERSTORMS. THE EASTER WEEKEND OVER SOUTH FLORIDA LOOKS DRY NOW. THEREFORE...THE POPS HAVE BEEN REMOVED OVER SOUTH FLORIDA THIS WEEKEND ALONG WITH SKIES MOSTLY CLEAR. LONG TERM... LOW PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC WATERS EARLY NEXT WEEK ALLOWING FOR HIGH PRESSURE TO BUILD INTO THE SOUTHEASTERN UNITED STATES. THIS WILL ALLOW FOR AN EASTERLY WIND FLOW OVER THE AREA EARLY NEXT WEEK. SO SOME LOW LEVEL MOISTURE SHOULD RETURN TO SOUTH FLORIDA EARLY NEXT WEEK LEADING TO A FEW SHOWERS. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER SOUTH FLORIDA FOR EARLY NEXT WEEK. AVIATION... SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM OR TWO...ARE LIKELY TO DEVELOP THIS AFTERNOON...ESPECIALLY AT KAPF AND KPBI. DUE TO LOW TS RISK...FEEL VCSH IS SUFFICIENT...WITH VFR CONDITIONS MOST PREVALENT. SOUTH WINDS WILL INCREASE TODAY AND BECOME GUSTY THIS AFTERNOON. AS COLD FRONT MOVES IN OVERNIGHT...WINDS WILL SHIFT TO WEST. MARINE... THE WINDS TODAY WILL BE FROM THE SOUTH/SOUTHWEST DIRECTION AT 15 KNOTS OR LESS BEFORE SWINGING TO A NORTHERLY DIRECTION LATE TONIGHT INTO WEDNESDAY. THE WIND DIRECTION WILL CONTINUE TO SWING TO A EASTERLY DIRECTION WEDNESDAY NIGHT INTO THURSDAY WITH SPEEDS AT 15 KNOTS OR LESS. THERE WILL ALSO BE A SMALL NORTHEAST SWELL WORKING INTO THE SOUTH FLORIDA WATERS FROM THE NORTH WEDNESDAY NIGHT INTO THURSDAY. THE SEAS SHOULD REMAIN BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS TODAY INTO WEDNESDAY...BUT COULD GET TO 7 FEET IN PALM BEACH WATERS ON THURSDAY DUE TO THE SMALL NORTHEAST SWELLS. CLIMATE... THE HIGHS AROUND 90 DEGREES TODAY OVER THE EAST COAST METRO AREAS WILL BE GETTING CLOSE TO THE RECORD HIGHS FOR THIS DATE WHICH ARE: CITIES FORECAST HIGHS RECORD HIGHS MIA 90 93 - 1975 FLL 90 93 - 2001 PBI 90 93 - 1999 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 AM EDT TUE APR 15 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT TUE APR 15 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD -SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE ERN LAKE. TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 459 AM EDT TUE APR 15 2014 ...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO THURSDAY... SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON 290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS. ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS. NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL SOMEWHERE IN THE WESTERN CWA. EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF. THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1 INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1 RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA. SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM. FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND 850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER. RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO PREFERRED BY HPC. NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE WEEKEND. ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85 MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES. THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT LAKES. MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF THESE DAYS ENDS UP DRY WITH SOME SUNSHINE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 728 AM EDT TUE APR 15 2014 THE COMBINATION OF AN UPPER LEVEL DISTURBANCE AND COLD LIGHT NNW FLOW OVER PARTIAL OPEN WATERS OF WRN LAKE SUPERIOR WILL BE ENOUGH TO SUPPORT SCT -SHSN THIS MORNING WITH OCNL CONDITIONS INTO THE MVFR RANGE AT IWD/CMX. OTHERWISE...DIURNAL HEATING WILL ALSO SUPPORT ADDITIONAL -SHSN WITH POTENTIAL FOR CONDITIONS NEAR INTO THE MVFR CATEGORY. AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING WITH VFR CONDITIONS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 459 AM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. 30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 459 AM EDT TUE APR 15 2014 GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR MIZ001>005-009>011-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1010 AM EDT TUE APR 15 2014 .SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST TODAY... AHEAD OF A COLD FRONT THAT WILL CROSS THE REGION THIS AFTERNOON THROUGH EARLY EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH TONIGHT THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1010 AM TUESDAY... HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST) INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT. PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID- UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S EAST. -GIH MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE 30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 235 AM TUESDAY... WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE) WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900 MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER- ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE 50S. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE 20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO 33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER... GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50 DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 740 AM TUESDAY... 24 HOUR TAF PERIOD: A LINE OF HEAVY SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE THROUGH THE AREA...APPROACHING KRWI...AND MOVING OVER THE TERMINAL DURING THE NEXT HOUR OR TWO. WITH THE BREAK IN THE PRECIP THIS MORNING AT THE OTHER TERMINALS...CONDITIONS HAVE/SHOULD TEMPORARILY IMPROVE(D) BACK TO VFR/MVFR. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND WILL LIKELY RESULT IN PERIODS OF REDUCED CIGS AND VISBYS. IN THE WAKE OF THESE AFT/EVE SHOWERS AND STORMS...THE COLD FRONT WILL TRAVERSE FROM WEST TO EAST THROUGH CENTRAL NC. ALTHOUGH WINDS WILL REMAIN STRONG THROUGH 12Z... EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE FRONT. THE GUSTS MAY BRIEFLY DIE OUT BETWEEN 06Z AND 12Z WEDNESDAY MORNING. CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT...WITH VFR CONDITIONS EXPECTED FOR THE LAST 6-12 HOURS OF THE TAF PERIOD. -KC LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010- 021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/MWS SHORT TERM...MWS/KCP LONG TERM...KCP AVIATION...KCP CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1153 AM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY. UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST TO START THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1150 AM EDT MONDAY...BASED ON THE RAPID COOL-OFF OVER THE NC MTNS...AS WELL AS UPSTREAM SNOW REPORTS...I NOW HAVE SOME MINOR SNOW ACCUMULATIONS ABOVE 5KFT OVER THE SMOKY MOUNTAINS AND THE NRN NC MTNS. ALSO ADJUSTED TEMPS AND DEWPOINTS ACROSS THE REGION TO ACCOUNT FOR THE RAPID TEMPERATURE DROP BEHIND THE FRONT. NO CHANGE ON THE THINKING IN THE WARM SECTOR. SHOWERS AND A FEW TSTMS SHOULD INCREASE ALONG AND AHEAD OF THE FRONT...BUT NOT EXPECTING ENOUGH HEATING FOR A SEVERE THREAT UNTIL THE CONVECTION GETS EAST OF THE FORECAST AREA. AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE. THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS. AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY. I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD BRING SOME GOOD GUSTS TO THE MTNS. AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS. AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT. THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE... WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS. THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA. WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU MIDNIGHT. PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED. WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20 DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3 KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT. WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES WARMER THAN VALUES OBSERVED ON WED. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5 TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK. THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH. MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON AFTERNOON. && .AVIATION /16Z TUESDAY THROUGH SATURDAY/... AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING TOWARD DAYBREAK. ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING. OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE SYSTEM DEVELOPS ALONG THE COAST. CONFIDENCE TABLE... 16-22Z 22-04Z 04-10Z 10-16Z KCLT HIGH 95% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 90% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 83% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 89% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 92% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOWS FOR WEDNESDAY APRIL 16... AVL...26 IN 1943 CLT...29 IN 2008 GSP...24 IN 1907 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR GAZ010-017-018-026-028-029. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017. NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082- 501>510. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053- 058-059-062>065-501-503-505-507-509. SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR SCZ001>014-019. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY/RWH CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1044 AM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY. UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST TO START THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE. THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS. AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY. I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD BRING SOME GOOD GUSTS TO THE MTNS. AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS. AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT. THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE... WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS. THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA. WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU MIDNIGHT. PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED. WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20 DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3 KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT. WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES WARMER THAN VALUES OBSERVED ON WED. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5 TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK. THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH. MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON AFTERNOON. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING TOWARD DAYBREAK. ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING. OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE SYSTEM DEVELOPS ALONG THE COAST. CONFIDENCE TABLE... 14-20Z 20-02Z 02-08Z 08-14Z KCLT HIGH 93% HIGH 94% HIGH 100% HIGH 100% KGSP HIGH 90% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 84% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 88% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 89% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 92% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOWS FOR WEDNESDAY APRIL 16... AVL...26 IN 1943 CLT...29 IN 2008 GSP...24 IN 1907 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR GAZ010-017-018-026-028-029. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017. NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082- 501>510. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053- 058-059-062>065-501-503-505-507-509. SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR SCZ001>014-019. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY/RWH CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
912 AM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY. UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST TO START THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY. I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD BRING SOME GOOD GUSTS TO THE MTNS. AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS. AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT. THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE... WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS. THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA. WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU MIDNIGHT. PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED. WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20 DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3 KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT. WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES WARMER THAN VALUES OBSERVED ON WED. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5 TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK. THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH. MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON AFTERNOON. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING TOWARD DAYBREAK. ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING. OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE SYSTEM DEVELOPS ALONG THE COAST. CONFIDENCE TABLE... 13-19Z 19-01Z 01-07Z 07-13Z KCLT HIGH 87% HIGH 94% HIGH 100% HIGH 100% KGSP HIGH 92% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 85% HIGH 98% HIGH 100% HIGH 100% KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 92% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 90% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOWS FOR WEDNESDAY APRIL 16... AVL...26 IN 1943 CLT...29 IN 2008 GSP...24 IN 1907 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR GAZ010-017-018-026-028-029. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017. NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082- 501>510. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053- 058-059-062>065-501-503-505-507-509. SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR SCZ001>014-019. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY/RWH SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY/RWH CLIMATE...
AREA FORECAST DISCUSSION
NWS MIAMI FL
133 PM EDT TUE APR 15 2014 .AVIATION... MESOSCALE GUIDANCE HAS BEEN LESS THAN IMPRESSIVE IN TERMS OF SHOWER COVERAGE FOR THIS AFTERNOON...BUT STILL APPEARS ISOLATED/SCATTERED ACTIVITY WILL FORM DURING MID/LATE- AFTERNOON HOURS. VCSH CONTINUED IN TAFS TO ACCOUNT FOR THIS. VFR CONDITIONS SHOULD PREVAIL BUT LOCALIZED RESTRICTIONS PLAUSIBLE IN/NEAR CONVECTION. THUNDER CANT BE RULED OUT BUT PROB IS QUITE LOW. SSE WINDS OF 15-25 KTS WILL BECOME SSW LATER THIS AFTERNOON. THE WEST LATE THIS EVENING AS COLD FRONT MOVES IN. WINDS TURN NORTHERLY WEDNESDAY MORNING...AND MODELS INDICATED LOW STRATUS COULD INVADE FROM NORTH AND HOLD OVER SOUTH FLORIDA INTO AFTERNOON. ELECTED TO NOT GO AGGRESSIVE THIS FAR OUT...BUT BKN035 INTRODUCED BEGINNING ROUGHLY AT SUNRISE. && .PREV DISCUSSION... /ISSUED 950 AM EDT TUE APR 15 2014/ UPDATE... SOMEWHAT OF A FORECAST DILEMMA THIS MORNING CONCERNING THE CHANCE OF AFTERNOON THUNDERSTORMS. A COLD FRONT CURRENTLY IS MOVING ACROSS THE FLORIDA PANHANDLE WITH A BAND OF SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT THROUGH THE BIG BEND AREA AND INTO THE NORTHEAST GULF OF MEXICO. PLENTY OF SUN IS OCCURRING ACROSS SOUTH FLORIDA WHICH WILL PROVIDE SUFFICIENT DIURNAL HEATING TODAY AS THE FRONT APPROACHES CENTRAL FLORIDA LATE THIS AFTERNOON. HOWEVER, HEREIN LIES THE QUESTION. THE 12Z MFL SOUNDING CONTINUES TO SHOW A QUITE STABLE LAYER OF AIR WITH THE BASE AT ABOUT 10K AND EXTENDING UPWARDS TO ABOUT 15K. THIS IS GOING TO BE A INHIBITING FACTOR WITH ANY SHOWER ACTIVITY HAVING A TOUGH TIME BREAKING THROUGH THIS STABLE CAP. HOWEVER, DUE TO THE SUFFICIENT HEATING THAT WILL BE TAKING PLACE AND MAXIMUM AFTERNOON TEMPERATURES APPROACHING THE 90 DEGREE MARK BY 2-3 PM EDT THIS COULD PROVIDE THE NECESSARY BUOYANCY TO PENETRATE THE STABLE LAYER. SOME OF THE HIGH RESOLUTION SHORT TERM COMPUTER MODELS DO SHOW SOME CONVECTIVE DEVELOPMENT AT THAT TIME AND THEN MOVING TOWARDS THE EAST COAST IN THE GENERAL SOUTHWEST STEERING FLOW. STILL, THE HRRR WHICH IS VERY RELIABLE FOR SOUTH FLORIDA ONLY SHOWS ISOLATED DEVELOPMENT AND MAINLY ALONG THE PALM BEACH COASTAL AREA. THE FORTUNATE ASPECT OF THE HRRR IS THAT IT UPDATES EVERY HOUR SO WILL BE TAKING A CLOSE LOOK AT ITS SOLUTIONS OVER THE NEXT SEVERAL HOURS AND MAY NEED TO SCALE BACK POPS AT LEAST OVER THE WESTERN PORTIONS OF THE PENINSULA. KOB PREV DISCUSSION... /ISSUED 722 AM EDT TUE APR 15 2014/ SHORT TERM... ONE OR TWO OF THE STORMS COULD EVEN BECOME STRONG LATE THIS AFTERNOON INTO THIS EVENING MAINLY AROUND THE LAKE OKEECHOBEE REGION AND THE EAST COAST METRO AREAS WHERE PERHAPS BETTER CONVERGENCE WILL BE. THE PRIMARY IMPACTS FROM THE STRONG STORMS WILL BE GUSTY WINDS...AS A LOW LEVEL JET OF 40 TO 50 KNOTS WILL BE MOVING THROUGH THE AREA. SO WILL MENTION THIS IN THE HWO MORNING PACKAGE. DRIER AIR WILL THEN BE WORKING INTO SOUTH FLORIDA FOR LATE TONIGHT. HOWEVER...THE DRY AIR WILL NOT LAST LONG AS THE FRONT WILL STALL OVER THE FLORIDA KEYS LATE TONIGHT BEFORE MOVING BACK NORTHWARD THROUGH SOUTH FLORIDA WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THIS WILL BRING BACK SOME MOISTURE ALONG WITH A CHANCE OF SHOWERS TO THE AREA. SO WILL CONTINUE THE ISOLATED TO SCATTERED SHOWERS OVER SOUTH FLORIDA FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THE LATEST MEDIUM RANGE MODELS ARE NOW SHOWING LOW PRESSURE DEVELOPING OVER THE NORTHERN GULF OF MEXICO LATE THIS WEEK AND MOVING EAST ACROSS NORTH FLORIDA BEFORE MOVING INTO THE WESTERN ATLANTIC WATERS THIS WEEKEND. THIS WILL PUSH THE FRONT BACK SOUTHWARD THROUGH SOUTH FLORIDA FRIDAY NIGHT. SO THE TROPICAL MOISTURE WILL REMAIN IN PLACE FOR LATE THIS WEEK BEFORE DRIER AIR WORKS INTO SOUTH FLORIDA FOR THIS WEEKEND. SO WILL CONTINUE THE SCATTERED POPS OVER SOUTH FLORIDA LATE THIS WEEK ALONG WITH A THREAT OF THUNDERSTORMS. THE EASTER WEEKEND OVER SOUTH FLORIDA LOOKS DRY NOW. THEREFORE...THE POPS HAVE BEEN REMOVED OVER SOUTH FLORIDA THIS WEEKEND ALONG WITH SKIES MOSTLY CLEAR. LONG TERM... LOW PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC WATERS EARLY NEXT WEEK ALLOWING FOR HIGH PRESSURE TO BUILD INTO THE SOUTHEASTERN UNITED STATES. THIS WILL ALLOW FOR AN EASTERLY WIND FLOW OVER THE AREA EARLY NEXT WEEK. SO SOME LOW LEVEL MOISTURE SHOULD RETURN TO SOUTH FLORIDA EARLY NEXT WEEK LEADING TO A FEW SHOWERS. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER SOUTH FLORIDA FOR EARLY NEXT WEEK. MARINE... THE WINDS TODAY WILL BE FROM THE SOUTH/SOUTHWEST DIRECTION AT 15 KNOTS OR LESS BEFORE SWINGING TO A NORTHERLY DIRECTION LATE TONIGHT INTO WEDNESDAY. THE WIND DIRECTION WILL CONTINUE TO SWING TO A EASTERLY DIRECTION WEDNESDAY NIGHT INTO THURSDAY WITH SPEEDS AT 15 KNOTS OR LESS. THERE WILL ALSO BE A SMALL NORTHEAST SWELL WORKING INTO THE SOUTH FLORIDA WATERS FROM THE NORTH WEDNESDAY NIGHT INTO THURSDAY. THE SEAS SHOULD REMAIN BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS TODAY INTO WEDNESDAY...BUT COULD GET TO 7 FEET IN PALM BEACH WATERS ON THURSDAY DUE TO THE SMALL NORTHEAST SWELLS. CLIMATE... THE HIGHS AROUND 90 DEGREES TODAY OVER THE EAST COAST METRO AREAS WILL BE GETTING CLOSE TO THE RECORD HIGHS FOR THIS DATE WHICH ARE: CITIES FORECAST HIGHS RECORD HIGHS MIA 90 93 - 1975 FLL 90 93 - 2001 PBI 90 93 - 1999 && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 67 80 71 84 / 30 30 30 40 FORT LAUDERDALE 70 81 74 85 / 30 30 30 30 MIAMI 71 82 73 85 / 30 30 30 40 NAPLES 67 84 68 88 / 20 20 20 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....54/BNB AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
634 PM EDT TUE APR 15 2014 .SYNOPSIS... A STRONG COLD FRONT MOVES OFF THE COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TONIGHT AND SETTLES OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... COLD FRONT CRNTLY MOVING ACROSS SERN VA/NRN NC ERLY THIS EVE WITH A NRLY SOLID BAND OF MDT-HVY SHWRS/TSTRMS ALONG IT. HAVING TO HAND EDIT THE TEMP/DP TEMP GRID AS MODELS NOT HANDLING THE 20+ DEGREE TMP DROP IN 1 HOUR BEHIND THE FROPA THAT WELL. ADJUSTED GRIDS PER LATEST RADAR TRENDS. INCREASED POPS TO CATEGORICAL ALL AREAS NEXT 1-3 HRS AS DEEP MOISTURE CONTINUES TO FEED INTO THIS SYSTM EVEN BEHIND THE FRNT. STILL EXPECT THIS SYSTM TO SWEEP OFFSHORE AFTER MIDNIGHT WITH FAIRLY RAPID CLRG. STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. FOR A FEW HOURS THIS EVENING...WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE EXPECTED OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING. THESE WINDS ARE ALSO INDICATED IN THE VIRGINIA PORTION OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY. LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA EASTERN SHORE. THE FREEZE WARNING IS ALSO IN EFFECT FOR THE MD EASTERN SHORE EXCEPT FOR OCEAN CITY AND FOR NORTHAMPTON COUNTY NORTH CAROLINA. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST DURING THE SHORT TERM. DUE TO N TO NW WINDS AND COLD TEMPERATURES ALOFT... CLOUDS FROM STREAMERS ARE EXPECTED OVER THE CHESAPEAKE BAY AND EASTERN PORTIONS OF SOUTH SIDE HAMPTON ROADS ON WEDNESDAY... ESPECIALLY IN THE MORNING. TEMPERATURES WILL REMAIN COOL WEDNESDAY AND THURSDAY WITH HIGHS MAINLY IN THE 50S. ON WEDNESDAY... TEMPERATURES MAY GET NO HIGHER THAN THE MID TO UPR 40S ALONG THE COAST INCLUDING THE NORFOLK AND VIRGINIA BEACH AREA AND THE LOWER EASTERN SHORE. LOWS THURSDAY MORNING AGAIN ARE FORECAST TO FALL TO AROUND 30 OVER INTERIOR PORTIONS. SOME FROST IS POSSIBLE AS WELL INCLUDING LOCATIONS THAT ONLY FALL TO THE LOW TO MID 30S. ANY NEEDED HEADLINES WILL BE DEFERRED TO LATER SHIFTS. TEMPERATURES WARM A BIT FRIDAY WITH HIGHS IN THE LOWER 60S OVER INTERIOR AREAS. THERE WILL BE A SLIGHT CHANCE FOR RAIN TOWARD THE COAST...ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME. MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED COVERAGE TO NO HIGHER THAN 40 PERCENT. TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70 DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT 10 DEGREES ABOVE NORMAL). && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR. IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY. SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA. && .MARINE... GALE WARNGS WILL CONTINUE AS PLANNED FOR ALL WTRS TDY INTO TNGT. A STRONG COLD FRNT IS CURRENTLY APPROACHING THE MID ATLANTIC CST...WITH GUSTY SLY FLOW AHEAD OF THE FRNT TO BE FOLLOWED BY STRONGER NW FLOW BEHIND THE FRNT. EXPECT GUSTS UP TO 35-40 KT OVRNGT AS THE FRNT PUSHES OFFSHORE AND HI PRES BLDS IN FROM THE W WITH LARGE PRES RISES. WAVES WILL RISE TO 4 TO 6 FT OVR THE BAY...AND SEAS WILL RISE TO 6 TO 9 FT ON THE CSTL WTRS. HI PRES CONTINUES TO BLD IN THRU WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN SIGNIFICANTLY. STILL HAVE THE GALES ENDING AT 7 AM FOR THE BAY/RIVERS...AND HOLDING INTO THE ERLY AFTN FOR THE CST AND SOUND. HI PRES SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES WED NGT THRU FRI...AS A WEAK CSTL TROF DEVELOPS OFF THE SE CST. THIS WILL RESULT IN A PROLONGED PERIOD OF NE WINDS AND ELEVATED SEAS THRU THE END OF THE WEEK. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024. NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012. VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049- 060>085-087>094. MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654. GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658. GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638. && $$ SYNOPSIS...LSA NEAR TERM...MPR/LSA SHORT TERM...LSA LONG TERM...BMD AVIATION...LKB/JAB MARINE...MAS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
406 PM EDT TUE APR 15 2014 .SYNOPSIS... A STRONG COLD FRONT WILL MOVE OFF THE COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TUESDAY NIGHT AND SETTLES OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... UPPER AIR ANALYSIS HAS A LONG WAVE TROUGH EXTENDING FROM CANADA ACROSS THE EASTERN GREAT LAKES TO THE SOUTHERN APPALACHIANS. A COLD FRONT EXTENDED FROM NORTH OF NEW ENGLAND ACROSS NEW JERSEY TO CENTRAL VIRGINIA TO GEORGIA. THESE TWO FEATURES WILL MOVE QUICKLY TO THE EAST OF THE AREA TONIGHT. THE COLD FRONT IS EXPECTED TO EXIT THE AREA ON THE NORTH CAROLINA COAST AROUND 02Z. WHILE THUNDERSTORMS ARE STILL POSSIBLE...SEVERE THUNDERSTORMS LOOK UNLIKELY AT THIS POINT. PART OF THIS IS DUE TO STABILIZATION FROM EARLIER PRECIPITATION. SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE AHEAD OF THE FRONT AND ESPECIALLY ALONG THE FRONT. THUNDERSTORMS WILL END NEAR THE TIME OF THE FRONTAL PASSAGE. RAIN CONTINUES IN MOST LOCATIONS THIS EVENING...ENDING FROM WEST TO EAST LATE THIS EVENING AND EARLY WEDNESDAY MORNING. INCLUDING RAIN THAT FELL EARLIER TODAY...MOST LOCATIONS CAN EXPECT A TOTAL OF AROUND AN INCH OF RAIN FROM THE EVENT WITH SOME LOCALLY HIGHER AMOUNTS. STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. FOR A FEW HOURS THIS EVENING...WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE EXPECTED OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING. THESE WINDS ARE ALSO INDICATED IN THE VIRGINIA PORTION OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY. TEMPERATURES DROP QUICKLY BEHIND THE FRONT WITH READINGS FALLING INTO THE 40S WEST OF INTERSTATE 95 THIS EVENING. LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA EASTERN SHORE. THE FREEZE WARNING IS ALSO IN EFFECT FOR THE MD EASTERN SHORE EXCEPT FOR OCEAN CITY AND FOR NORTHAMPTON COUNTY NORTH CAROLINA. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST DURING THE SHORT TERM. DUE TO N TO NW WINDS AND COLD TEMPERATURES ALOFT... CLOUDS FROM STREAMERS ARE EXPECTED OVER THE CHESAPEAKE BAY AND EASTERN PORTIONS OF SOUTH SIDE HAMPTON ROADS ON WEDNESDAY... ESPECIALLY IN THE MORNING. TEMPERATURES WILL REMAIN COOL WEDNESDAY AND THURSDAY WITH HIGHS MAINLY IN THE 50S. ON WEDNESDAY... TEMPERATURES MAY GET NO HIGHER THAN THE MID TO UPR 40S ALONG THE COAST INCLUDING THE NORFOLK AND VIRGINIA BEACH AREA AND THE LOWER EASTERN SHORE. LOWS THURSDAY MORNING AGAIN ARE FORECAST TO FALL TO AROUND 30 OVER INTERIOR PORTIONS. SOME FROST IS POSSIBLE AS WELL INCLUDING LOCATIONS THAT ONLY FALL TO THE LOW TO MID 30S. ANY NEEDED HEADLINES WILL BE DEFERRED TO LATER SHIFTS. TEMPERATURES WARM A BIT FRIDAY WITH HIGHS IN THE LOWER 60S OVER INTERIOR AREAS. THERE WILL BE A SLIGHT CHANCE FOR RAIN TOWARD THE COAST...ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME. MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED COVERAGE TO NO HIGHER THAN 40 PERCENT. TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70 DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT 10 DEGREES ABOVE NORMAL). && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR. IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY. SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA. && .MARINE... GALE WARNGS WILL CONTINUE AS PLANNED FOR ALL WTRS TDY INTO TNGT. A STRONG COLD FRNT IS CURRENTLY APPROACHING THE MID ATLANTIC CST...WITH GUSTY SLY FLOW AHEAD OF THE FRNT TO BE FOLLOWED BY STRONGER NW FLOW BEHIND THE FRNT. EXPECT GUSTS UP TO 35-40 KT OVRNGT AS THE FRNT PUSHES OFFSHORE AND HI PRES BLDS IN FROM THE W WITH LARGE PRES RISES. WAVES WILL RISE TO 4 TO 6 FT OVR THE BAY...AND SEAS WILL RISE TO 6 TO 9 FT ON THE CSTL WTRS. HI PRES CONTINUES TO BLD IN THRU WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN SIGNIFICANTLY. STILL HAVE THE GALES ENDING AT 7 AM FOR THE BAY/RIVERS...AND HOLDING INTO THE ERLY AFTN FOR THE CST AND SOUND. HI PRES SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES WED NGT THRU FRI...AS A WEAK CSTL TROF DEVELOPS OFF THE SE CST. THIS WILL RESULT IN A PROLONGED PERIOD OF NE WINDS AND ELEVATED SEAS THRU THE END OF THE WEEK. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024. NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012. VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049- 060>085-087>094. MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654. GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658. GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638. && $$ SYNOPSIS...LSA NEAR TERM...LSA SHORT TERM...LSA LONG TERM...BMD AVIATION...LKB/JAB MARINE...MAS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
308 PM EDT TUE APR 15 2014 .SYNOPSIS... A STRONG COLD FRONT WILL CROSS THE AREA TODAY...THEN MOVE OFF THE COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TUESDAY NIGHT AND SETTLES OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY AND THURSDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... THE SEVERE THREAT FOR THIS AFTERNOON AND EVENING HAS DIMINISHED FROM EARLIER FORECASTS. THE SPC SLIGHT RISK HAS BEEN REMOVED. THIS DOES NOT ELIMINATE THE POSSIBILITY OF SEVERE THUNDERSTORMS. SHOWERS AND THUNDERSTORMS ALONG THE COLD FRONT COULD STILL MIX DOWN SOME WIND GUSTS THAT WOULD APPROACH OR EXCEED SEVERE CRITERIA. THE SEVERE POTENTIAL HAS DIMINISHED FOR A FEW REASONS: THE LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED OFFSHORE AROUND NOON RESULTED IN SOME STABILIZING. THUNDERSTORMS OVER GEORGIA IS ROBBING SOME OF THE INFLUX OF MOISTURE TO THE AREA. FINALLY...THE BACKING OF SURFACE WINDS TO SE IS NOT AS IMPRESSIVE AS EARLIER EXPECTED. AT 1 PM EDT...THE COLD FRONT WAS NEAR THE SHENANDOAH VALLEY IN NORTHERN VIRGINIA AND JUST EAST OF LYNCHBURG. A BAND OF HEAVY RAIN AND GUSTY WINDS CAN BE EXPECTED WITH THE FRONTAL PASSAGE. MOST WIND GUSTS SHOULD BE 40 MPH OR LESS BUT ISOLATED SEVERE GUSTS ARE STILL POSSIBLE. HIGH TEMPERATURES TODAY WILL GENERALLY RUN BETWEEN 70 AND 75. TEMPERATURES WILL FALL NOTICEABLY FOLLOWING THE COLD FRONT WITH READINGS IN THE 50S IN THE PIEDMONT COUNTIES AND INTERIOR NORTHERN NECK BY LATE AFTERNOON. STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE EXPECTED THIS EVENING OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING. THESE WINDS ARE ALSO EXPECTED IN THE VIRGINIA PORTION OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY. RAIN MOVES OFF THE COAST LATE THIS EVENING. SKIES WILL CLEAR OVERNIGHT FROM WEST TO EAST. . LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA EASTERN SHORE. THE FREEZE WARNING IS IN EFFECT FOR THE MD EASTERN SHORE EXCEPT FOR OCEAN CITY. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/... COLD WEDNESDAY UNDER SUNNY SKIES. LIKELY WILL BE SOME STREAMERS OVER THE BAY INTO SE VA/NE NC WEDS MORNING. H85 TEMPS WILL FALL TO ~-5C (-2 STD DEV)...TRANSLATING TO DAYTIME TEMPS GENERALLY IN THE LOW 50S...EVEN UNDER THE STRONG APRIL SUN. TEMPS AGAIN MAY FALL TO AROUND FREEZING OVER INLAND COUNTIES WED NIGHT-THURS MORNING. THERE IS A POSSIBILITY FOR LIGHT RAIN NEAR THE NC COAST BY THURS. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME. MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED COVERAGE TO NO HIGHER THAN 40 PERCENT. TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70 DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT 10 DEGREES ABOVE NORMAL). && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR. IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY. SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA. && .MARINE... RAISED GALE WARNINGS FOR ALL MARINE ZONES...REMOVED RAMP-UP SCA`S AS WE ARE WITHIN ~ 12 HRS OF THE ONSET OF GALE CONDITIONS. SOUTHERLY FLOW TODAY WILL INCREASE TO AROUND 20-25 KT WITH GUSTS TO 30 KT...AS PRESSURE FALLS MOVE INTO THE AREA AHEAD OF THE APPROACHING COLD FRONT. HOWEVER...STRONGER WINDS ARE ANTICIPATED BETWEEN ABOUT 20Z AND 00Z AS WINDS SHIFT IN ASSOCIATION WITH THE FRONT (AND MAY BE ENHANCED BY SCATTERED CONVECTION). THIS EVENING...IMPRESSIVE PRESSURE RISES ON THE ORDER OF 12 TO 15 MB IN A 6 HR PERIOD SHOULD BRING GUSTS OF 35-40 KT FOR ALL ZONES. THIS WILL ALSO USHER IN MUCH COLDER AIR THAT WILL ENHANCE MIXING OVER THE WATERS. WAVES WILL BLD TO 4 TO 6 FT OVR THE CHES BAY...AND SEAS WILL BLD TO 5 TO 9 FT ON THE COASTAL WATERS. HI PRES WILL THEN BLD JUST TO THE N BY WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN SIGNIFICANTLY. HAVE THE GALES ENDING AT 12Z FOR THE BAY/RIVERS...BUT HOLDING INTO EARLY AFTN FOR THE COAST AND CURRITUCK SOUND. HIGH PRESSURE SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES WED NGT THRU FRI...AS A WEAK COASTAL TROUGH DEVELOPS OFF THE SE COAST. THIS WILL RESULT IN NE WINDS AND ELEVATED SEAS THRU THE END OF THE WEEK. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024. NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012. VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049- 060>085-087>094. MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654. GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658. GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638. && $$ SYNOPSIS...LSA NEAR TERM...LSA SHORT TERM...SAM LONG TERM...BMD AVIATION...LKB/JAB MARINE...LKB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
145 PM EDT TUE APR 15 2014 .SYNOPSIS... A STRONG COLD FRONT WILL CROSS THE AREA TODAY...THEN MOVE OFF THE COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TUESDAY NIGHT AND SETTLES OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... THE SEVERE THREAT FOR THIS AFTERNOON AND EVENING HAS DIMINISHED FROM EARLIER FORECASTS. THE SPC SLIGHT RISK HAS BEEN REMOVED. THIS DOES NOT ELIMINATE THE POSSIBILITY OF SEVERE THUNDERSTORMS. SHOWERS AND THUNDERSTORMS ALONG THE COLD FRONT COULD STILL MIX DOWN SOME WIND GUSTS THAT WOULD APPROACH OR EXCEED SEVERE CRITERIA. THE SEVERE POTENTIAL HAS DIMINISHED FOR A FEW REASONS: THE LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED OFFSHORE AROUND NOON RESULTED IN SOME STABILIZING. THUNDERSTORMS OVER GEORGIA IS ROBBING SOME OF THE INFLUX OF MOISTURE TO THE AREA. FINALLY...THE BACKING OF SURFACE WINDS TO SE IS NOT AS IMPRESSIVE AS EARLIER EXPECTED. AT 1 PM EDT...THE COLD FRONT WAS NEAR THE SHENANDOAH VALLEY IN NORTHERN VIRGINIA AND JUST EAST OF LYNCHBURG. A BAND OF HEAVY RAIN AND GUSTY WINDS CAN BE EXPECTED WITH THE FRONTAL PASSAGE. MOST WIND GUSTS SHOULD BE 40 MPH OR LESS BUT ISOLATED SEVERE GUSTS ARE STILL POSSIBLE. HIGH TEMPERATURES TODAY WILL GENERALLY RUN BETWEEN 70 AND 75. TEMPERATURES WILL FALL NOTICEABLY FOLLOWING THE COLD FRONT WITH READINGS IN THE 50S IN THE PIEDMONT COUNTIES AND INTERIOR NORTHERN NECK BY LATE AFTERNOON. STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE EXPECTED THIS EVENING OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING. THESE WINDS ARE ALSO EXPECTED IN THE VIRGINIA PORTION OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY. RAIN MOVES OFF THE COAST LATE THIS EVENING. SKIES WILL CLEAR OVERNIGHT FROM WEST TO EAST. . LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA EASTERN SHORE. THE FREEZE WARNING IS IN EFFECT FOR THE MD EASTERN SHORE EXCEPT FOR OCEAN CITY. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... COLD WEDNESDAY UNDER SUNNY SKIES. LIKELY WILL BE SOME STREAMERS OVER THE BAY INTO SE VA/NE NC WEDS MORNING. H85 TEMPS WILL FALL TO ~-5C (-2 STD DEV)...TRANSLATING TO DAYTIME TEMPS GENERALLY IN THE LOW 50S...EVEN UNDER THE STRONG APRIL SUN. TEMPS AGAIN MAY FALL TO AROUND FREEZING OVER INLAND COUNTIES WED NIGHT-THURS MORNING. THERE IS A POSSIBILITY FOR LIGHT RAIN NEAR THE NC COAST BY THURS. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... STRONG SFC HIGH PRESSURE REMAINS ANCHORED OVER NEW ENGLAND TO BEGIN THE MEDIUM RANGE FORECAST PERIOD, RESULTING IN CONTINUED NE FLOW OVER THE MID ATLANTIC FRIDAY. TEMPERATURES WILL BE COOL TO BEGIN THE PERIOD FRIDAY...ABOUT ONE STANDARD DEVIATION BELOW NORMAL...WITH TEMPS MODERATING A BIT SATURDAY. ALOFT, NORTHERN STREAM SHORTWAVE TROUGH, AND ATTENDANT SFC LOW IS EXPECTED TO PUSH ACROSS THE MID MS VLY TOWARDS THE EASTERN GREAT LAKES FRI-SAT, EVENTUALLY PUSHING A MAINLY DRY COLD FRONT THROUGH SAT NGT AND EARLY SUNDAY. BOTH MODELS DO TAKE A PIECE OF SHORTWAVE ENERGY ACROSS THE MID-SOUTH TOWARDS THE CAROLINA COAST FRIDAY-SATURDAY, WITH RESULTANT WEAK INVERTED TROUGHING THAT DEVELOPS PROMPTING SOME LOW POPS LATER FRIDAY AND SATURDAY. THE 12Z/14 EURO SOLUTION REMAINS A BIT WETTER THAN THE PROGRESSIVE GFS SOLUTION. HAVE SPLIT THE DIFFERENCE BETWEEN THE GFS/UKMET FOR THIS PACKAGE. RIGHT NOW, IT APPEARS THAT THE BEST RAIN CHC WOULD BE OVER EASTERN SECTIONS ALONG THE COASTAL TROUGH FRIDAY NIGHT THROUGH MIDDAY SATURDAY. UPPER TROUGH EJECTS NORTHEAST LATER SATURDAY, WITH SHORTWAVE RIDGING ARRIVING FROM THE WEST SHUNTING SYSTEM OFFSHORE. QUICK CLEARING EXPECTED THEREAFTER TOWARDS THE TAIL END OF THE PERIOD (EASTER SUNDAY AND MONDAY). && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR. IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY. SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA. && .MARINE... RAISED GALE WARNINGS FOR ALL MARINE ZONES...REMOVED RAMP-UP SCA`S AS WE ARE WITHIN ~ 12 HRS OF THE ONSET OF GALE CONDITIONS. SOUTHERLY FLOW TODAY WILL INCREASE TO AROUND 20-25 KT WITH GUSTS TO 30 KT...AS PRESSURE FALLS MOVE INTO THE AREA AHEAD OF THE APPROACHING COLD FRONT. HOWEVER...STRONGER WINDS ARE ANTICIPATED BETWEEN ABOUT 20Z AND 00Z AS WINDS SHIFT IN ASSOCIATION WITH THE FRONT (AND MAY BE ENHANCED BY SCATTERED CONVECTION). THIS EVENING...IMPRESSIVE PRESSURE RISES ON THE ORDER OF 12 TO 15 MB IN A 6 HR PERIOD SHOULD BRING GUSTS OF 35-40 KT FOR ALL ZONES. THIS WILL ALSO USHER IN MUCH COLDER AIR THAT WILL ENHANCE MIXING OVER THE WATERS. WAVES WILL BLD TO 4 TO 6 FT OVR THE CHES BAY...AND SEAS WILL BLD TO 5 TO 9 FT ON THE COASTAL WATERS. HI PRES WILL THEN BLD JUST TO THE N BY WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN SIGNIFICANTLY. HAVE THE GALES ENDING AT 12Z FOR THE BAY/RIVERS...BUT HOLDING INTO EARLY AFTN FOR THE COAST AND CURRITUCK SOUND. HIGH PRESSURE SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES WED NGT THRU FRI...AS A WEAK COASTAL TROUGH DEVELOPS OFF THE SE COAST. THIS WILL RESULT IN NE WINDS AND ELEVATED SEAS THRU THE END OF THE WEEK. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024. NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012. VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049- 060>085-087>094. MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654. GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658. GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638. && $$ SYNOPSIS...LSA NEAR TERM...LSA SHORT TERM...SAM LONG TERM...MAM/JEF AVIATION...LKB/JAB MARINE...LKB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
531 PM EDT TUE APR 15 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE WED INTO WED NIGHT. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON 285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE 4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT. WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7 INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY 1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO WARNING. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 531 PM EDT TUE APR 15 2014 LONG TERM PORTION OF THE FCST WILL BEGIN COLD/WINTRY AS SHORTWAVE TAKES ADVANTAGE OF LINGERING TIGHT THERMAL GRADIENT OVER THE AREA BTWN DEPARTING UNUSUALLY COLD AIR MASS FOR MID APR AND WARMTH SPREADING OUT ACROSS THE CNTRL/SRN PLAINS. TEMPS WILL THEN SLOWLY MODERATE AS DEEP TROF AND ASSOCIATED LATE SEASON ARCTIC AIR LIFT TO GREENLAND...AND PACIFIC AIR MAKES INCREASING INROADS ACROSS THE CONUS AND SRN CANADA. HEADING DOWN THE ROAD...IT LOOKS LIKE TEMPS NEXT WEEK WILL GENERALLY FLUCTUATE AROUND NORMAL...BUT NOT SIGNIFICANTLY ABOVE OR BLO NORMAL DURING THE TEMP SWINGS. THERE ARE SOME INDICATIONS FROM GEM ENSEMBLES AND GFS RUNS THAT THE PATTERN MAY BE FAIRLY ACTIVE OVER THE NEXT COUPLE OF WEEKS WHICH WILL MEAN RAINFALL FOR MOST IF NOT ALL PCPN EVENTS. HOPEFULLY...SIGNIFICANT RAINFALL WILL BE AVOIDED AS THE SNOWMELT SEASON RESUMES. BEGINNING WED NIGHT...A HVY/WET SNOW EVENT WILL BE UNDERWAY AS SHORTWAVE APPROACHES FROM THE UPPER MISSISSIPPI VALLEY. WITH 12Z MODEL RUNS...MODELS THAT HAD MAX QPF AXIS ON THE NW SIDE OF THE MODEL SPREAD HAVE SHIFTED SLIGHTLY S AND E. RESULT IS IMPROVING MODEL AGREEMENT NOW ON WHERE AXIS OF HEAVIEST PCPN WILL SET UP. IT APPEARS MAX QPF AXIS SHOULD RUN ROUGHLY FROM JUST N OF THE TWIN CITIES TO THE HURON MTNS. THE NAM IS DISPLACED A LITTLE TO THE NW OF THIS AXIS WHILE THE GEM REGIONAL/HEMISPHERIC ARE DISPLACED A LITTLE TO THE SE. ALTHOUGH SFC LOW ASSOCIATED WITH SHORTWAVE WILL BE WEAKENING AS IT TRACKS FROM THE NRN/CNTRL PLAINS TO THE UPPER LAKES...BEST COMBINATION OF FORCING/MOISTURE WILL COME TOGETHER FROM ERN MN E AND NE NTO UPPER MI BEFORE SYSTEM BEGINS TO FALL APART. AT THE UPPER LEVELS...RIGHT ENTRANCE OF UPPER JET STREAK RUNNING FROM NRN LAKE SUPERIOR/NRN ONTARIO EASTWARD WILL PROVIDE HEALTHY UPPER DIVERGENCE. THERE ARE EVEN SOME HINTS OF BRIEF UPPER JET COUPLING WITH LEFT EXIT OF JET SHIFTING ACROSS THE UPPER MIDWEST THAT IS SUPPORTING THE SHORTWAVE. AT THE LOWER LEVELS...STRONG ISENTROPIC ASCENT IS NOTED WITH MIXING RATIOS OF 3 TO 4G/KG AVBL AROUND 700-750MB. IN ADDITION...THERE IS STRONG FRONTOGENESIS WITH NEGATIVE EPV/CONVECTIVE INSTABILITY NOTED OVERTOP THE FGEN. FINALLY...STEEP MIDLEVEL LAPSE RATES ARE NOTED ADVECTING INTO THE SRN SIDE OF THE PCPN AREA. ALL THIS POINTS TO THE LIKELIHOOD FOR HEAVIER BANDING OF SNOW WITHIN THE OVERALL MDT/HVY PCPN AREA OR EVEN CONVECTIVE SNOW AT TIMES...CERTAINLY NOT ATYPICAL FOR SPRINGTIME HVY SNOW EVENTS. ULTIMATE PLACEMENT OF HEAVIEST SNOW WILL HINGE ON WHERE THESE HEAVIER SNOWBANDS OR CONVECTIVE ELEMENTS SET UP. AS IT STANDS NOW...LOCATIONS W OF KIMT/KMQT LINE SHOULD HAVE NO PROBLEM REACHING WARNING CRITERIA WITH STORM TOTAL AMOUNTS AROUND 1 FOOT...PROBABLY IN MANY LOCATIONS. ADVY ISSUED FOR NEXT TIER OF COUNTIES E MAY IN FACT NEED TO BE UPGRADED TO WARNINGS GIVEN MODEL TRENDS. FINALLY... EVEN THE FAR E COUNTIES OF SCHOOLCRAFT AND LUCE MAY NEED TO BE ADDED TO AN ADVY IF THE E TREND HOLDS UP IN NEXT SET OF MODEL RUNS. PCPN WINDS DOWN QUICKLY THU AND WILL LIKELY END. SFC HIGH PRES THEN BUILDS INTO THE UPPER LAKES THU NIGHT THRU FRI NIGHT TO PROVIDE A PERIOD OF QUIET WEATHER. NAM IN PARTICULAR SUGGESTS LOW CLOUDS MAY LINGER THU NIGHT...AND THAT MAY BE THE CASE WITH SHALLOW COLD AIR MASS OVER EXPANDING OPEN WATER ON LAKE SUPERIOR. IF CLOUDS DO CLEAR OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI UNDER MID LEVEL TROF AND ASSOCIATED THERMAL TROF. NOT OUT OF THE QUESTION THAT A FEW FLURRIES COULD EVEN DEVELOP. FRI HIGHS WILL BE IN THE 30S N WITH A CHILLY WIND OFF THE ICE TO THE 40S S. WITH CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT. MODELS THEN DIVERGE WITH PROGRESSION OF NEXT SHORTWAVE FEATURE MOVING OFF THE PACIFIC IN LOWER AMPLITUDE FLOW...THOUGH AGREEMENT IS IMPROVING WITH TODAYS 12Z MODEL RUNS. GEM IS STRONGER WITH WAVE AND IS HEAVIER WITH THE QPF THAN THE GFS/ECWMF. HOWEVER...BOTH THE GFS AND ECMWF ARE TRENDING TOWARD A WETTER SYSTEM NOW. SOME -RA POSSIBLY MIXED WITH A LITTLE SNOW OVER HIGHER TERRAIN WILL PROBABLY REACH THE W SAT AFTN...THEN SPREAD E SAT NIGHT/SUN. WITH WETTER TRENDS NOTED...WILL TRENDING POPS UP TO CHC. MON/TUE...ECMWF HAS BEEN CONSISTENT SHOWING TROF DEVELOPMENT INTO THE W COAST WITH DOWNSTREAM RIDGE BUILDING INTO THE ROCKIES/WRN PLAINS WHILE TROF SETTLES INTO THE ERN CONUS. THE GFS IS CONSIDERABLY MORE PRONOUNCED WITH EASTWARD EXTENT OF RIDGE/HIGHER HEIGHTS INTO THE GREAT LAKES...BUT THE 12Z GFS IS NOW SHOWING SIGNS OF HEADING IN THE DIRECTION OF THE ECMWF. WILL LEAN TOWARD THE MORE CONSISTENT ECMWF WHICH TYPICALLY VERIFIES BETTER. RESULT IS A COOLER THAN GFS SCENARIO...BUT STILL CLOSE TO NORMAL FOR TEMPS. IF ANY MINOR WAVES TRACK SE ACROSS THE AREA INTO THE ERN TROF...THERE MAY BE SOME SCT LIGHT -SHRA AT TIMES. AT THIS POINT...NOTHING SUGGESTS THE NEED FOR AN EXPLICIT MENTION OF PCPN MON OR TUE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 138 PM EDT TUE APR 15 2014 DIURNAL HEATING AND THE PRESENCE OF AN UPPER LEVEL TROUGH WILL SUPPORT -SHSN WITH POTENTIAL FOR CONDITIONS INTO THE MVFR CATEGORY THROUGH 21Z. AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING WITH VFR CONDITIONS. LOOK FOR CONDITIONS TO LOWER TO IFR AT KIWD BY LATE WED MORNING AND TO MVFR AT KCMX AND KSAW BTWN 16-18Z WITH THE ONSET OF SNOW AHEAD OF APPROACHING SYSTEM OVER THE NRN PLAINS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 531 PM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT WITH SFC HIGH PRES RIDGE OVER THE AREA. APPROACHING LOW PRESSURE SYSTEM FM THE PLAINS WILL RESULT IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. WENT WITH A GALE WARNING FOR FAR WRN LAKE SUPERIOR WEDNESDAY AFTN INTO THU MORNING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 531 PM EDT TUE APR 15 2014 RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS... RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS. HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO 1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES ARRIVE NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY FROM NOON WEDNESDAY TO NOON EDT THURSDAY FOR MIZ006-013. WINTER STORM WARNING FROM NOON WEDNESDAY TO 11 AM EDT THURSDAY FOR MIZ004-084. WINTER STORM WARNING FROM NOON WEDNESDAY TO NOON EDT THURSDAY FOR MIZ005. WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ WEDNESDAY TO 11 AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011. WINTER STORM WARNING FROM 2 PM WEDNESDAY TO NOON EDT THURSDAY FOR MIZ001-003. WINTER WEATHER ADVISORY FROM 9 AM WEDNESDAY TO 10 AM CDT THURSDAY FOR MIZ012. LAKE SUPERIOR... GALE WARNING FROM 2 PM EDT /1 PM CDT/ WEDNESDAY TO 11 AM EDT /10 AM CDT/ THURSDAY FOR LSZ162. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...ROLFSON AVIATION...VOSS MARINE...VOSS HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
157 PM EDT TUE APR 15 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT TUE APR 15 2014 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD -SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE ERN LAKE. TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE. TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 459 AM EDT TUE APR 15 2014 ...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO THURSDAY... SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON 290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS. THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS. ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS. NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL SOMEWHERE IN THE WESTERN CWA. EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF. THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1 INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1 RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA. SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM. FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND 850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER. RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO PREFERRED BY HPC. NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE WEEKEND. ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85 MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES. THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT LAKES. MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF THESE DAYS ENDS UP DRY WITH SOME SUNSHINE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 138 PM EDT TUE APR 15 2014 DIURNAL HEATING AND THE PRESENCE OF AN UPPER LEVEL TROUGH WILL SUPPORT -SHSN WITH POTENTIAL FOR CONDITIONS INTO THE MVFR CATEGORY THROUGH 21Z. AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING WITH VFR CONDITIONS. LOOK FOR CONDITIONS TO LOWER TO IFR AT KIWD BY LATE WED MORNING AND TO MVFR AT KCMX AND KSAW BTWN 16-18Z WITH THE ONSET OF SNOW AHEAD OF APPROACHING SYSTEM OVER THE NRN PLAINS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 459 AM EDT TUE APR 15 2014 WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. 30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST PERIOD. && .HYDROLOGY... ISSUED AT 459 AM EDT TUE APR 15 2014 GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR MIZ001>005-009>011-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...VOSS MARINE...JLA HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
255 PM EDT TUE APR 15 2014 .SYNOPSIS...A STRONG COLD FRONT WILL CROSS THE AREA THROUGH EARLY EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH LATE TONIGHT THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1010 AM TUESDAY... HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST) INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT. PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID- UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S EAST. -GIH MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE 30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 255 PM TUESDAY... WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE) WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900 MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER- ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE 50S. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE 20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO 33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS THURSDAY AND THURSDAY NIGHT... HIGH PRESSURE AND DRY AIRMASS WILL MEAN FAIR WEATHER FOR THURSDAY. HIGH CLOUDS WILL BE ON THE INCREASE LATE AS SW FLOW ALOFT INCREASES AHEAD OF THE SHORT WAVE CROSSING THE SOUTHERN PLAINS. WITH LOW LEVEL THICKNESSES REBOUNDING 30-40M FROM WEDNESDAY...LOOK FOR HIGHS IN THE MID 60S. STILL COOL THURSDAY NIGHT WITH LOWS 5-10 DEGREES BELOW NORMAL...RANGING FROM THE UPPER 30S TO LOWER 40S. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 255 PM TUESDAY... AT THE START OF FRIDAY...THE UPPER TROUGH WILL BE CROSSING THE MISSISSIPPI RIVER VALLEY. MEANWHILE...A SOUTHERN STREAM SHORTWAVE MOVING ACROSS THE NE GOMEX WILL MOVE TOWARD THE WESTERN ATLANTIC BY DAYS END. IN RESPONSE...SURFACE LOW PRESSURE WILL DEVELOP IN VICINITY OF THE GULF STREAM AND LIFT TO THE NE AS THE AFOREMENTIONED SHORT WAVE MOVES EAST. MEANWHILE...THE NORTHERN STREAM UPPER TROUGH AXIS WILL CROSS THE CAROLINAS BETWEEN 00-06Z SATURDAY. RIGHT NOW IT APPEARS THAT THESE SYSTEMS WILL HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER FRIDAY AND FRIDAY NIGHT...MAINLY BECAUSE...1) THE MOISTURE ASSOC WITH THE SYSTEM OFF THE COAST IS PROGGED TO REMAIN WELL TO OUR EAST...AND 2) THE NORTHERN TROUGH AXIS WILL MOVE ACROSS OUR AREA MOISTURE-STARVED...WITH THE BULK OF ITS MOISTURE REMAINING WELL TO OUR NORTH. THEN IN THE WAKE OF THE UPPER TROUGH AXIS AND SFC COLD FRONT PASSAGE SATURDAY MORNING...HIGH PRESSURE AND DRY AIRMASS WILL BUILD SOUTH ACROSS THE CAROLINAS AND PROVIDE FAIR AND SEASONABLE WEATHER FOR THE REST OF WEEKEND. UNSETTLED WEATHER MAY RETURN EARLY NEXT WEEK WITH A SHORT WAVE EMBEDDED IN THE NW FLOW MOVING ACROSS OUR AREA LATE MONDAY THROUGH MIDDAY TUESDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 240 PM TUESDAY... ADVERSE AVIATION CONDITIONS WILL DOMINATE FOR THE NEXT 6-9 HOURS OR SO... FOLLOWED BY QUICK IMPROVEMENT TO VFR... BUT BRISK GUSTY WINDS WILL PERSIST. A COLD FRONT IS CURRENTLY MOVING THROUGH CENTRAL NC. PATCHY SHOWERS HAVE PRECEDED THIS FRONT ACROSS THE ENTIRE AREA IN RECENT HOURS... BUT ALONG AND JUST AHEAD OF THIS FRONT... A SOLID BAND OF HEAVY SHOWERS AND A FEW STORMS WILL SWEEP EASTWARD FROM NOW THROUGH ABOUT 03Z. CURRENT TAFS REFLECT THIS WITH A PERIOD OF IFR VSBYS AND MVFR TO IFR CIGS... AND STRONG GUSTY WINDS THROUGH LATE THIS AFTERNOON. WINDS WILL SHIFT SUDDENLY WITH FRONTAL PASSAGE... AS WINDS FROM THE SW SHIFT AROUND TO NW AND GUST UP TO 25-35 KTS... SO AVIATION INTERESTS SHOULD KEEP A CLOSE TAB ON THE FRONTAL POSITION IN THE NEXT SEVERAL HOURS. BETWEEN 02Z (WEST) AND 06Z (EAST)... CIGS ARE LIKELY TO RISE TO VFR WITH P6SM VSBYS AS SKIES CLEAR OUT. BRISK WINDS FROM NW WILL PERSIST THE REST OF TONIGHT... SUSTAINED NEAR 12- 18 KTS WITH A FEW GUSTS... THEN WILL SWING AROUND TO BE FROM THE NORTH AND EVENTUALLY NORTHEAST VERY LATE TONIGHT THROUGH WED MORNING... WITH VFR CONDITIONS LIKELY. LOOKING BEYOND 18Z WED... VFR CONDITIONS LIKELY THROUGH THU... ALTHOUGH THERE IS A CHANCE OF IFR CIGS WITH STRATUS AT FAY/RWI AS SURFACE WINDS SHIFT AROUND TO BE FROM THE SE AND BRING IN ATLANTIC LOW LEVEL MOISTURE. THIS CHANCE IS GREATER LATE THU NIGHT INTO FRI MORNING. A MID LEVEL TROUGH WILL MOVE THROUGH THE EASTERN US FRI THROUGH SAT... AND MAY BRING A PERIOD OF SUB-VFR CONDITIONS... BUT UNCERTAINTY IN THE DETAILS WITH THIS IS HIGH. -GIH && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010- 021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/MWS SHORT TERM...MWS/KCP LONG TERM...NP AVIATION...HARTFIELD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 PM EDT TUE APR 15 2014 .SYNOPSIS...A STRONG COLD FRONT WILL CROSS THE AREA THROUGH EARLY EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTH LATE TONIGHT THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1010 AM TUESDAY... HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST) INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT. PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID- UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S EAST. -GIH MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE 30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 235 AM TUESDAY... WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE) WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND. COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900 MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER- ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE 50S. PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT 12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE 20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO 33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER... GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50 DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 240 PM TUESDAY... ADVERSE AVIATION CONDITIONS WILL DOMINATE FOR THE NEXT 6-9 HOURS OR SO... FOLLOWED BY QUICK IMPROVEMENT TO VFR... BUT BRISK GUSTY WINDS WILL PERSIST. A COLD FRONT IS CURRENTLY MOVING THROUGH CENTRAL NC. PATCHY SHOWERS HAVE PRECEDED THIS FRONT ACROSS THE ENTIRE AREA IN RECENT HOURS... BUT ALONG AND JUST AHEAD OF THIS FRONT... A SOLID BAND OF HEAVY SHOWERS AND A FEW STORMS WILL SWEEP EASTWARD FROM NOW THROUGH ABOUT 03Z. CURRENT TAFS REFLECT THIS WITH A PERIOD OF IFR VSBYS AND MVFR TO IFR CIGS... AND STRONG GUSTY WINDS THROUGH LATE THIS AFTERNOON. WINDS WILL SHIFT SUDDENLY WITH FRONTAL PASSAGE... AS WINDS FROM THE SW SHIFT AROUND TO NW AND GUST UP TO 25-35 KTS... SO AVIATION INTERESTS SHOULD KEEP A CLOSE TAB ON THE FRONTAL POSITION IN THE NEXT SEVERAL HOURS. BETWEEN 02Z (WEST) AND 06Z (EAST)... CIGS ARE LIKELY TO RISE TO VFR WITH P6SM VSBYS AS SKIES CLEAR OUT. BRISK WINDS FROM NW WILL PERSIST THE REST OF TONIGHT... SUSTAINED NEAR 12- 18 KTS WITH A FEW GUSTS... THEN WILL SWING AROUND TO BE FROM THE NORTH AND EVENTUALLY NORTHEAST VERY LATE TONIGHT THROUGH WED MORNING... WITH VFR CONDITIONS LIKELY. LOOKING BEYOND 18Z WED... VFR CONDITIONS LIKELY THROUGH THU... ALTHOUGH THERE IS A CHANCE OF IFR CIGS WITH STRATUS AT FAY/RWI AS SURFACE WINDS SHIFT AROUND TO BE FROM THE SE AND BRING IN ATLANTIC LOW LEVEL MOISTURE. THIS CHANCE IS GREATER LATE THU NIGHT INTO FRI MORNING. A MID LEVEL TROUGH WILL MOVE THROUGH THE EASTERN US FRI THROUGH SAT... AND MAY BRING A PERIOD OF SUB-VFR CONDITIONS... BUT UNCERTAINTY IN THE DETAILS WITH THIS IS HIGH. -GIH && .CLIMATE... THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING... AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED: WED 04/16 THU 04/17 LOW/YEAR LOW MAX/YEAR LOW/YEAR FAY: 28/1943 56/1950 31/1953 GSO: 25/1943 48/1929 29/1953 RDU: 28/1950 46/1890 29/1962 && .RAH WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010- 021>026-038>041-073>077-083-084. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/MWS SHORT TERM...MWS/KCP LONG TERM...KCP AVIATION...HARTFIELD CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
148 PM EDT TUE APR 15 2014 .SYNOPSIS... A COLD FRONT WILL MOVE OFF THE CAROLINA COAST TONIGHT AS UNSEASONABLY COLD HIGH PRESSURE BUILDS ACROSS OUR REGION AND REMAINS INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST TO START THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 145 PM EDT MONDAY...A LINE OF SHOWERS AND TSTMS HAS DEVELOPED AHEAD OF THE SFC COLD FRONT. THIS IS PRETTY MUCH WHAT WAS EXPECTED AND THE LINE SHOULD MARCH EASTWARD ACROSS THE REST OF THE FORECAST AREA DURING THE REMAINDER OF THE AFTN. AS OF 1150 AM EDT MONDAY...BASED ON THE RAPID COOL-OFF OVER THE NC MTNS...AS WELL AS UPSTREAM SNOW REPORTS...I NOW HAVE SOME MINOR SNOW ACCUMULATIONS ABOVE 5KFT OVER THE SMOKY MOUNTAINS AND THE NRN NC MTNS. ALSO ADJUSTED TEMPS AND DEWPOINTS ACROSS THE REGION TO ACCOUNT FOR THE RAPID TEMPERATURE DROP BEHIND THE FRONT. NO CHANGE ON THE THINKING IN THE WARM SECTOR. SHOWERS AND A FEW TSTMS SHOULD INCREASE ALONG AND AHEAD OF THE FRONT...BUT NOT EXPECTING ENOUGH HEATING FOR A SEVERE THREAT UNTIL THE CONVECTION GETS EAST OF THE FORECAST AREA. AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE. THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS. AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY. I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD BRING SOME GOOD GUSTS TO THE MTNS. AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS. AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT. THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE... WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS. THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA. WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU MIDNIGHT. PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED. WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20 DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 210 PM TUESDAY...A DRY AND COOL ARIMASS WILL DOMINATE THE WEATHER THROUGH THURSDAY. AT THE SURFACE...A CP HIGH CENTERED OVER NEW ENGLAND WILL SLOWLY MOVE NORTHEAST...WITH A DRY WEDGE REMAINING ALONG THE EAST SLOPES OF THE APPALACHIANS. 12Z MODELS CONTINUE TO SHOW AN INCREASE IN MOISTURE ON FRI AS A SHORT WAVE TROUGH APPROACHES FROM THE WEST AND WINDS VEER TO A MORE EASTERLY/UPSLOPE COMPONENT. ALSO...CYCLOGENESIS IS STILL EXPECTED ALONG THE OLD FRONTAL ZONE OVER THE CENTRAL GULF AS THE UPPER WAVE APPROACHES. HOWEVER...WILL DISCOUNT THE CMH SOLUTION OF A MORE NORTHERN DEVELOPMENT OF THE LOW AND SIGNIFICANT QPF EXTENDING NORTH INTO THE AREA AND ACCEPT THE IDEA OF THE GFS/ECM THAT THE ASSOCIATED QPF WILL STAY WELL SOUTH OF THE AREA. THEREFORE EXPECT QPFTO BE MINIMAL OR NON-EXISTANT. WILL HAVE SOME VERY LOW END POPS OVER THE MOUNTAINS WHERE UPSLOPE FLOW COULD SQUEEZE OUT SOME SPRINKLES. THIS IDEA IS SUPPORTED BY THE NAM/SREF. THE HIGHEST IMPACT WEATHER THROUGH THE SHORT TERM WILL BE THE COLD TEMPS AGAIN WED NIGHT. WITH VERY FAVORABLE RADIATIONAL COOLING CONDITIONS ALONG WITH THE DRY AIRMASS...FROST/FREEZE CONDITIONS ARE EXPECTED EARLY THU. FREEZING TEMPS ARE A GOOD BET ACROSS ALL OF THE MOUNTAINS/FOOTHILLS AND PORTIONS OF THE PIEDMONT. WILL BE POSTING A FREEZE WATCH FOR MOST OF THE AREA FOR WED NIGHT. ALSO...SOME SCT FROST CAN`T BE RULED OUT EARLY FRI OVER NORTHERN AREAS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5 TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK. THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH. MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON AFTERNOON. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AT KCLT...A LINE OF SHOWERS AND TSTMS WILL CROSS THE AIRFIELD BETWEEN 18-20 UTC. EXPECT GUSTY AND ERRATIC WINDS AND VERY HEAVY RAIN AS THE LINE PASSES. WINDS WILL SHIFT TO THE NORTHWEST BEHIND THE LINE AS A COLD FRONT CROSSES THE AIRFIELD. MVFR CIGS ARE EXPECTED TO PERSIST FOR A COUPLE HOURS AFTER THE FRONTAL PASSAGE. WINDS WILL GUST UP TO 28-30 KTS INTO THE EVENING HOURS. LATER TONIGHT THE WINDS WILL VEER TO THE NORTHEAST AS HIGH PRESSURE MOVES INTO THE MID-ATLANTIC STATES. ELSEWHERE...A COLD FRONT WITH ASSOCIATED SHRA/TSTMS WAS CROSSING THE AIRFIELDS AT KGSP/KGMU AT ISSUANCE TIME. WINDS WILL SHIFT TO THE NORTHWEST BEHIND THE LINE OF STORMS...THOUGH SCT SHOWERS AND MVFR CIGS AREA EXPECTED TO PERSIST FOR A COUPLE HOURS BEHIND THE FRONT. WINDS MAY GUST AS HIGH AS 30 KTS INTO THE EVENING HOURS. WINDS AT KAVL WILL BE STRONGER...GUSTING ALMOST TO 40KTS FROM THE NW INTO THE EVENING HOURS. OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE SYSTEM DEVELOPS ALONG THE COAST. CONFIDENCE TABLE... 17-23Z 23-05Z 05-11Z 11-17Z KCLT HIGH 87% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 93% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 95% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 96% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 93% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 93% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOWS FOR WEDNESDAY APRIL 16... AVL...26 IN 1943 CLT...29 IN 2008 GSP...24 IN 1907 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR GAZ010-017-018-026-028-029. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017. NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082- 501>510. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053- 058-059-062>065-501-503-505-507-509. SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY FOR SCZ001>014-019. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY CLIMATE...