Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/02/15


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
950 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 945 PM MDT FRI MAY 1 2015 MINOR UPDATES PLANNED AT THIS TIME. MAINLY SOME LINGERING SHOWERS THIS EVENING. WL GO WITH SHOWERS VS TSTMS IN THE GRIDS FOR THE REST OF THIS EVENING. UPDATE ISSUED AT 641 PM MDT FRI MAY 1 2015 THE FOCUS FOR THUNDERSTORMS HAS SHIFTED TO THE NORTH AND EAST OF DENVER FOR THE MOST PART SO HAVE STARTED TO BACK OFF THE POPS ESPECIALLY OVER THE WESTERN PART OF THE CWA. THE POPS MAY STILL BE A BIT OVERDONE SINCE THE HRRR HINTS AT SOME ADDITIONAL ACTIVITY OVER THE NEXT COUPLE OF HOURS...MAINLY TO THE NORTH NEAR FORT COLLINS AND GREELEY. NOT CONVINCED THIS WILL HAPPEN BUT DO NOT WANT TO LESSEN THE POPS ANY FURTHER TIL I KNOW FOR SURE. IF A STRONG ENOUGH OUTFLOW COULD SLIPS INTO DENVER FROM THE NORTH...IT COULD STILL TRIGGER SOME ADDITIONAL DEVELOPMENT. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 THUNDERSTORMS ARE PRESENTLY MOVING OVER THE PALMER DIVIDE AND OFF THE FOOTHILLS OF BOULDER AND JEFFERSON COUNTY. SOUTHEASTERLY LOW LEVEL WINDS AND SURFACE DEW POINTS IN THE MID AND UPPER 40S SHOULD BE SUFFICIENT TO KEEP THUNDERSTORMS DEVELOPING ACROSS THE PLAINS EARLY THIS EVENING. HAIL UP TO THREE-QUARTERS OF AN INCH WILL BE THE MOST COMMON THREAT FROM THE PULSE-TYPE CONVECTION. WIND SHEAR ALOFT DOES NOT SEEM TO BE STRONG ENOUGH FOR ORGANIZED SUPERCELLS TO DEVELOP. RAINFALL AMOUNTS FROM ALERT GAGES HAVE SHOWN RAINFALL AMOUNTS STAYING LESS THAN A HALF INCH. SOME AREAS MAY RECEIVE SOME STANDING WATER IMMEDIATELY AFTER STORM PASSAGE...BUT NO OTHER PROBLEMS ARE EXPECTED. SKIES SHOULD BECOME PARTLY CLOUDY TO MOSTLY CLEAR LATER TONIGHT AFTER THE EVENING CONVECTION DIES DOWN. SOUTHERLY WINDS ARE EXPECTED TO PREVAIL AS HIGH PRESSURE BUILDS OVER THE CENTRAL PLAINS. TOMORROW SHOULD BE A REPEAT OF TODAY AS THE FLAT UPPER RIDGE REMAINS OVER COLORADO AND MOISTURE REMAINS OVER THE STATE. DAYTIME HEATING WILL AGAIN BE SUFFICIENT TO DE-STABILIZE THE AIRMASS. ONCE AGAIN THE WIND STRUCTURE WILL BE WEAK...SO ONLY SCATTERED NON-SEVERE THUNDERSTORMS ARE EXPECTED. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 MODELS HAVE WEAK SOUTHWESTERLY FLOW ALOFT FOR THE CWA SATURDAY NIGHT THROUGH MONDAY WITH A WEAK UPPER CLOSED LOW TO MOVE INTO THE FOUR CORNERS BY 12Z TUESDAY MORNING. THE QG FIELDS HAVE WEAK UPWARD VERTICAL VELOCITY PROGGED FOR ALL THE CWA SATURDAY NIGHT THROUGH MONDAY NIGHT. THE BOUNDARY LAYER WINDS WILL BE PRETTY WEAK WITH NORMAL DIURNAL PATTERNS SATURDAY NIGHT. THEN A WEAK COLD FRONT WITH UPSLOPE NORTHEASTERLIES ARE PROGGED SUNDAY...WITH EAST-SOUTHEASTERLIES SUNDAY NIGHT THROUGH MONDAY NIGHT. MOISTURE- WISE...SATURDAY EVENING IS FAIRLY DRY. THIS CARRIES INTO SUNDAY MORNING...WITH A SIGNIFICANT INCREASE IN MOISTURE SUNDAY AFTERNOON. BY SUNDAY NIGHT...THE NAM AND ECMWF FURTHER INCREASE MOISTURE...CONTINUING INTO MONDAY. THE GFS DOES NOT DO THIS UNTIL MONDAY AFTERNOON. BOTH THE GFS AND ECMWF SHOW A VERY MOIST MONDAY NIGHT. THE QPF FIELDS HAVE A TAD OF MEASURABLE PRECIPITATION PROGGED SATURDAY EVENING. BY SUNDAY AFTERNOON...THERE IS MUCH MORE PROGGED. THERE IS QPF NOTED ALL SUNDAY NIGHT...MONDAY MORNING... THROUGH MONDAY EVENING...THEN LESS MONDAY OVERNIGHT. THE DEW POINTS ARE IN THE 30S AND LOWER 40S F SATURDAY NIGHT INTO SUNDAY...THEN THEY INCREASE INTO THE 40S TO LOWER 50S FROM LATER SUNDAY THROUGH MONDAY NIGHT. THERE IS SOME CAPE BOTH SATURDAY EVENING...THEN LATE DAY SUNDAY AS WELL...BUT VALUES ARE NOT ABOVE 1000 J/KG EITHER DAY. THERE IS LESS CAPE AROUND FOR LATE DAY MONDAY WITH NONE OVER THE EASTERN HALF OF THE PLAINS. FOR POPS...MINOR ONES SATURDAY EVENING...NOTHING OVERNIGHT...THEN MINOR AGAIN IN THE MOUNTAINS SUNDAY MORNING. BY SUNDAY AFTERNOON THROUGH MONDAY NIGHT WILL GO WITH 30-50%S. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 3-5 C COOLER THAN SATURDAY`S. MONDAY`S HIGHS ARE 1-5 C COOLER AGAIN FROM SUNDAY`S. FOR THE LATER DAYS...TUESDAY THROUGH FRIDAY...MODELS CONTINUE TO SHOW UPPER TROUGHINESS FOR THE CWA ALL FOUR DAYS. THERE IS GOOD MOISTURE MUCH OF THE TIME WITH THE EXCEPTION OF FRIDAY. IT WILL BE A WET...UNSETTLED PERIOD WITH TEMPERATURES A BIT BELOW NORMALS. && .AVIATION...(FOR THE TAFS THROUGH 06Z SATURDAY EVENING) ISSUED AT 945 PM MDT FRI MAY 1 2015 VFR CONDITIONS THROUGH MID AFTERNOON SATURDAY WITH DRAINAGE WINDS OVERNIGHT. COULD SEE ILS CIGS DEVELOPS WITH ANY DEVELOPING TSTMS AFTER 21Z SATURDAY. COVERAGE APPEARS ISOLATED WITH BETTER COVERAGE NORTH OF DENVER IF A WEAK DISTURBANCE MAKES ITS WAY ALONG THE NORTHERN BORDER IN THE AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...COOPER SHORT TERM...DANKERS LONG TERM...RJK AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
650 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 641 PM MDT FRI MAY 1 2015 THE FOCUS FOR THUNDERSTORMS HAS SHIFTED TO THE NORTH AND EAST OF DENVER FOR THE MOST PART SO HAVE STARTED TO BACK OFF THE POPS ESPECIALLY OVER THE WESTERN PART OF THE CWA. THE POPS MAY STILL BE A BIT OVERDONE SINCE THE HRRR HINTS AT SOME ADDITIONAL ACTIVITY OVER THE NEXT COUPLE OF HOURS...MAINLY TO THE NORTH NEAR FORT COLLINS AND GREELEY. NOT CONVINCED THIS WILL HAPPEN BUT DO NOT WANT TO LESSEN THE POPS ANY FURTHER TIL I KNOW FOR SURE. IF A STRONG ENOUGH OUTFLOW COULD SLIPS INTO DENVER FROM THE NORTH...IT COULD STILL TRIGGER SOME ADDITIONAL DEVELOPMENT. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 THUNDERSTORMS ARE PRESENTLY MOVING OVER THE PALMER DIVIDE AND OFF THE FOOTHILLS OF BOULDER AND JEFFERSON COUNTY. SOUTHEASTERLY LOW LEVEL WINDS AND SURFACE DEW POINTS IN THE MID AND UPPER 40S SHOULD BE SUFFICIENT TO KEEP THUNDERSTORMS DEVELOPING ACROSS THE PLAINS EARLY THIS EVENING. HAIL UP TO THREE-QUARTERS OF AN INCH WILL BE THE MOST COMMON THREAT FROM THE PULSE-TYPE CONVECTION. WIND SHEAR ALOFT DOES NOT SEEM TO BE STRONG ENOUGH FOR ORGANIZED SUPERCELLS TO DEVELOP. RAINFALL AMOUNTS FROM ALERT GAGES HAVE SHOWN RAINFALL AMOUNTS STAYING LESS THAN A HALF INCH. SOME AREAS MAY RECEIVE SOME STANDING WATER IMMEDIATELY AFTER STORM PASSAGE...BUT NO OTHER PROBLEMS ARE EXPECTED. SKIES SHOULD BECOME PARTLY CLOUDY TO MOSTLY CLEAR LATER TONIGHT AFTER THE EVENING CONVECTION DIES DOWN. SOUTHERLY WINDS ARE EXPECTED TO PREVAIL AS HIGH PRESSURE BUILDS OVER THE CENTRAL PLAINS. TOMORROW SHOULD BE A REPEAT OF TODAY AS THE FLAT UPPER RIDGE REMAINS OVER COLORADO AND MOISTURE REMAINS OVER THE STATE. DAYTIME HEATING WILL AGAIN BE SUFFICIENT TO DE-STABILIZE THE AIRMASS. ONCE AGAIN THE WIND STRUCTURE WILL BE WEAK...SO ONLY SCATTERED NON-SEVERE THUNDERSTORMS ARE EXPECTED. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 MODELS HAVE WEAK SOUTHWESTERLY FLOW ALOFT FOR THE CWA SATURDAY NIGHT THROUGH MONDAY WITH A WEAK UPPER CLOSED LOW TO MOVE INTO THE FOUR CORNERS BY 12Z TUESDAY MORNING. THE QG FIELDS HAVE WEAK UPWARD VERTICAL VELOCITY PROGGED FOR ALL THE CWA SATURDAY NIGHT THROUGH MONDAY NIGHT. THE BOUNDARY LAYER WINDS WILL BE PRETTY WEAK WITH NORMAL DIURNAL PATTERNS SATURDAY NIGHT. THEN A WEAK COLD FRONT WITH UPSLOPE NORTHEASTERLIES ARE PROGGED SUNDAY...WITH EAST-SOUTHEASTERLIES SUNDAY NIGHT THROUGH MONDAY NIGHT. MOISTURE- WISE...SATURDAY EVENING IS FAIRLY DRY. THIS CARRIES INTO SUNDAY MORNING...WITH A SIGNIFICANT INCREASE IN MOISTURE SUNDAY AFTERNOON. BY SUNDAY NIGHT...THE NAM AND ECMWF FURTHER INCREASE MOISTURE...CONTINUING INTO MONDAY. THE GFS DOES NOT DO THIS UNTIL MONDAY AFTERNOON. BOTH THE GFS AND ECMWF SHOW A VERY MOIST MONDAY NIGHT. THE QPF FIELDS HAVE A TAD OF MEASURABLE PRECIPITATION PROGGED SATURDAY EVENING. BY SUNDAY AFTERNOON...THERE IS MUCH MORE PROGGED. THERE IS QPF NOTED ALL SUNDAY NIGHT...MONDAY MORNING... THROUGH MONDAY EVENING...THEN LESS MONDAY OVERNIGHT. THE DEW POINTS ARE IN THE 30S AND LOWER 40S F SATURDAY NIGHT INTO SUNDAY...THEN THEY INCREASE INTO THE 40S TO LOWER 50S FROM LATER SUNDAY THROUGH MONDAY NIGHT. THERE IS SOME CAPE BOTH SATURDAY EVENING...THEN LATE DAY SUNDAY AS WELL...BUT VALUES ARE NOT ABOVE 1000 J/KG EITHER DAY. THERE IS LESS CAPE AROUND FOR LATE DAY MONDAY WITH NONE OVER THE EASTERN HALF OF THE PLAINS. FOR POPS...MINOR ONES SATURDAY EVENING...NOTHING OVERNIGHT...THEN MINOR AGAIN IN THE MOUNTAINS SUNDAY MORNING. BY SUNDAY AFTERNOON THROUGH MONDAY NIGHT WILL GO WITH 30-50%S. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 3-5 C COOLER THAN SATURDAY`S. MONDAY`S HIGHS ARE 1-5 C COOLER AGAIN FROM SUNDAY`S. FOR THE LATER DAYS...TUESDAY THROUGH FRIDAY...MODELS CONTINUE TO SHOW UPPER TROUGHINESS FOR THE CWA ALL FOUR DAYS. THERE IS GOOD MOISTURE MUCH OF THE TIME WITH THE EXCEPTION OF FRIDAY. IT WILL BE A WET...UNSETTLED PERIOD WITH TEMPERATURES A BIT BELOW NORMALS. && .AVIATION...(FOR THE TAFS THROUGH 06Z SATURDAY EVENING) ISSUED AT 641 PM MDT FRI MAY 1 2015 SHOULD SEE PRIMARILY VFR CONDITIONS THROUGH AT LEAST MID AFTERNOON SATURDAY. WL KEEP VCSH IN THE TAFS FOR A BIT LONGER. STILL SOME TSTMS NEAR FORT COLLINS AND GREELEY SO THE POSSIBILITY OF SOME REDEVELOPMENT IN DENVER DOES EXIST BUT IT DOES APPEAR TO BE LOW AT THIS TIME. BARRING SOME SORT OF OUTFLOW BOUNDARY SLIPPING IN FROM THE NORTH...WINDS SHOULD GO TO MORE OF A DRAINAGE PATTERN THE REST OF THIS EVENING. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...COOPER SHORT TERM...DANKERS LONG TERM...RJK AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1144 PM MDT WED APR 29 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 250 PM MDT WED APR 29 2015 UPPER RIDGE OVER THE AREA TODAY HAS SUPPRESSED CONVECTION OVER THE AREA. HOWEVER...HRRR AND RAP STILL SUGGEST A SMALL WINDOW FOR SOME ISOLATED SHOWERS/THUNDERSTORMS ACROSS THE SOUTHWEST MOUNTAINS AND SANGRE DE CRISTO MOUNTAINS LATE THIS AFTERNOON AND EVENING. SEEING SOME CU DEVELOPMENT ACROSS THE EASTERN SAN JUANS AND SOUTHERN SANGRES...SO WILL MAINTAIN SOME LOW GRADE POPS FOR THESE AREAS. MAIN IMPACT WILL BE AN ISOLATED LIGHTNING STRIKE ALONG WITH GUSTY WINDS. ON THURSDAY...A DISTURBANCE WILL MOVE THROUGH THE NRN U.S. ROCKIES DURING THE AFTERNOON. THIS WILL SEND A PREFRONTAL WIND SHIFT INTO THE PIKES PEAK REGION DURING THE AFTERNOON. INCREASING MID LEVEL MOISTURE AHEAD OF THE DISTURBANCE WILL PRODUCE A ROUND OF ISOLATED TO LOW END SCATTERED SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS. MEANWHILE...WITH THE BOUNDARY STALLING ACROSS NORTHERN EL PASO THIS WILL ALSO PROVIDE A FOCUS FOR THUNDERSTORM DEVELOPMENT DURING THE LATE AFTERNOON AND EARLY EVENING. THUNDERSTORMS WILL REMAIN FAIRLY HIGH BASED...WITH ERRATIC GUSTY WINDS AND LIGHTNING THE PRIMARY STORM THREATS. -KT .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 250 PM MDT WED APR 29 2015 ...INCREASING HEAVY RAIN THREAT EARLY NEXT WEEK... OUR AREA WILL BE UNDER QUASI-ZONAL FLOW ALOFT FOR THE END OF THE WEEK. A COUPLE WEAK DISTURBANCES WILL MOVE THROUGH THE FLOW WHICH WILL HELP GENERATE THUNDERSTORMS AND SHOWERS EACH AFTERNOON AND EVENING. A FRONTAL PUSH OVER THE PLAINS WILL LEAD TO SLIGHTLY COOLER WX ON FRIDAY...WITH TEMPS IN THE 70S OVER THE PLAINS. LOW CLOUDS OVER THE PLAINS SHOULD DISSIPATE BY LATE MORNING... AND INCREASED UPSLOPE OVER THE PLAINS FRI AFTERNOON SHOULD ALSO LEAD TO AN INCREASE IN CONVECTION IN THE AFTERNOON AND EVE. A COUPLE STORMS MAY BE ON THE STRONG SIDE...SO WILL HAVE TO WATCH THE BURN SCARS FRI AFTERNOON AND EVE...BUT STORMS SHOULD BE MOVING AT A DECENT CLIP AND WILL DISSIPATE OFF TO THE EAST FRI EVE. OVER THE WEEKEND...INCREASED ZONAL FLOW WILL BRING JUNE-LIKE TEMPS TO THE REGION...WITH MID 80S A POSSIBILITY FOR THE WARM SPOTS OVER THE PLAINS. EXPECT DIURNAL STORMS AGAIN...FORMING OVER THE HIGHER TRRN AND SHIFTING TO THE PLAINS IN THE EVENING. WILL SEE CONVECTION COVERAGE INCREASE THROUGH THE WEEKEND AS A STRONGER SHORT-WAVE MOVES OUT OF THE PACNW AND THEN THROUGH THE NRN ROCKIES. BY MONDAY...A CUT-OFF LOW OVER THE BAJA REGION WILL BEGIN MOVING INTO THE DESERT SW...AND INCREASED SRLY FLOW IN THE MID LEVELS WILL BRING INCREASED MOISTURE TO SE CO. SO...HEAVY RAIN CHANCES WILL BE ON THE INCREASE MONDAY AND ESPECIALLY BY TUESDAY...AS THE LOW MOVES INTO THE FOUR CORNERS REGION. MAIN THREAT WILL BE HEAVY RAIN BUT INCREASING SHEAR COULD ALSO BRING A FEW STRONG TO SVR STORMS AS THE LOW GETS CLOSER. AFTER TUE...MODELS DIVERGE A BIT ON HOW QUICKLY THE LOW EJECTS TO OUR NORTH AND EAST...AND ALSO THE IMPACT OF A SECOND LOW PRESSURE SYSTEM MOVING INTO THE PACNW. SO...UNCERTAINTY IS PRETTY HIGH BEYOND TUE...BUT IT LOOKS TO BE UNSETTLED THROUGH AT LEAST A GOOD PORTION OF NEXT WEEK. ROSE && .AVIATION... ISSUED AT 1144 PM MDT WED APR 29 2015 UPPER RIDGING WILL ALLOW VFR CONDITIONS TO CONTINUE OVER THE KALS...KCOS AND KPUB TAF SITES THROUGH TONIGHT. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS ALBANY NY
143 PM EDT THU APR 30 2015 .SYNOPSIS... MOST OF EASTERN NEW YORK AND WESTERN NEW ENGLAND WILL STAY DRY THIS AFTERNOON WITH SEASONABLE TEMPERATURES AND PARTLY SUNNY CONDITIONS. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 127 PM EDT...WEAK MID LEVEL RIDGING OVER W-CNTRL NY AHEAD OF A CLOSED LOW OVER THE MIDWEST/LOWER GREAT LAKES REGION WILL KEEP IT MAINLY DRY THIS AFTERNOON. A BROAD CUTOFF UPPER LOW NEAR THE CANADIAN MARITIMES IN THE WESTERN ATLANTIC WILL CONTINUE TO SPREAD SOME CLOUDS WESTWARD OVER WRN NEW ENGLAND AND ERN NY. AN ISOLATED SPRINKLE OR SHOWER IS POSSIBLE LATE THIS AFTERNOON/EARLY THIS EVENING OVER WRN NEW ENGLAND AND THE NRN CATSKILLS.THE LATEST 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP OVER HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. CLOUDS WILL CONTINUE TO INCREASE BASED ON THE LATEST SATELLITE PICTURE...SO EXPECT PARTLY SUNNY/MOSTLY CLOUDY CONDITIONS THIS AFTERNOON. HIGHS THIS AFTERNOON WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID/U60S FOR VALLEY AREAS...AND UPPER 50S TO LOWER 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THE END OF THE TAF PERIOD ENDING AT 18Z FRIDAY. AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. INTERVALS OF CLOUDS AT OR ABOVE 3500 FEET WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD. CLOUDS WILL BECOME BROKEN TO OVERCAST CLOUDS THIS AFTERNOON THROUGH TONIGHT. A VCSH GROUP WAS PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 8 KTS THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THROUGH 18Z FRIDAY. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY: MODERATE OPERATIONAL IMPACT. NUMEROUS -SHRA. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/WASULA NEAR TERM...FRUGIS/11/WASULA SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...11/NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
127 PM EDT THU APR 30 2015 .SYNOPSIS... MOST OF EASTERN NEW YORK AND WESTERN NEW ENGLAND WILL STAY DRY THIS AFTERNOON WITH SEASONABLE TEMPERATURES AND PARTLY SUNNY CONDITIONS. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 127 PM EDT...WEAK MID LEVEL RIDGING OVER W-CNTRL NY AHEAD OF A CLOSED LOW OVER THE MIDWEST/LOWER GREAT LAKES REGION WILL KEEP IT MAINLY DRY THIS AFTERNOON. A BROAD CUTOFF UPPER LOW NEAR THE CANADIAN MARITIMES IN THE WESTERN ATLANTIC WILL CONTINUE TO SPREAD SOME CLOUDS WESTWARD OVER WRN NEW ENGLAND AND ERN NY. AN ISOLATED SPRINKLE OR SHOWER IS POSSIBLE LATE THIS AFTERNOON/EARLY THIS EVENING OVER WRN NEW ENGLAND AND THE NRN CATSKILLS.THE LATEST 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP OVER HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. CLOUDS WILL CONTINUE TO INCREASE BASED ON THE LATEST SATELLITE PICTURE...SO EXPECT PARTLY SUNNY/MOSTLY CLOUDY CONDITIONS THIS AFTERNOON. HIGHS THIS AFTERNOON WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID/U60S FOR VALLEY AREAS...AND UPPER 50S TO LOWER 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH THURSDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /17Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HRS ENDING 12Z/01 AT KPOU/KPSF/KALB/KGFL...AS AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. INTERVALS OF CLOUDS AT OR ABOVE 3500 FEET WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD WITH MORE SCATTERED CLOUDS THIS MORNING...AND BROKEN TO OVERCAST CLOUDS THIS AFTERNOON THROUGH TONIGHT. A VCSH GROUP WAS PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE CEILING AT KPSF COULD LOWER TO 2500 FEET AFTER 09Z. THE WINDS WILL BE LIGHT AND VARIABLE IN DIRECTION AT 3 KT OR LESS THROUGH MID MORNING. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 10 KT IN THE LATE MORNING THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THIS EVENING AND TONIGHT. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/WASULA NEAR TERM...FRUGIS/11/WASULA SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
930 AM EDT THU APR 30 2015 .SYNOPSIS... MOST AREAS WILL STAY DRY TODAY WITH SEASONABLE TEMPERATURES AND PARTIAL SUNSHINE. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 930 AM EDT...WEAK RIDGING IS CURRENTLY IN PLACE OVER OUR REGION. A CLOSED OFF SHORTWAVE TROUGH IS DIVING OUT OF THE GREAT LAKES...WHILE A SLOW MOVING CUTOFF LOW REMAINS WELL TO OUR EAST OVER THE WESTERN ATLANTIC OCEAN. MOSTLY SUNNY TO SUNNY CONDITIONS AND TEMPERATURES IN THE MID 40S TO LOWER 50S PREVAILED ACROSS THE REGION. MOST OF THE REGION IS EXPECTED TO REMAIN MOSTLY SUNNY THIS MORNING. THE SHORTWAVE TROUGH OVER THE GREAT LAKES LOOKS TO DIVE TOWARDS THE MID ATLANTIC STATES TODAY. IT SHOULD REMAIN FAR ENOUGH SOUTHWEST OF OUR AREA TO AVOID HAVING A DIRECT IMPACT...BUT MAY SEND SOME MID AND HIGH LEVEL CLOUDS INTO OUR AREA BY THIS AFTERNOON. MEANWHILE...BROAD N-NE FLOW AROUND THE OCEANIC CLOSED LOW WILL ALLOW SOME LOWER MOISTURE TO WORK ITS WAY INTO OUR REGION AS WELL. THIS MOISTURE...ALONG WITH DAYTIME HEATING...WILL ALLOW FOR SOME DIURNAL CU/STRAOTCU CLOUDS TO DEVELOP THIS AFTN. A STRAY SHOWER OR SPRINKLE IS POSSIBLE OVER THE HIGHER ELEVATIONS LATE TODAY...BUT WIDESPREAD PRECIP ISN/T EXPECTED DUE TO ONLY VERY WEAK BROAD SCALE LIFT IN PLACE. THE 12Z 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP THIS AFTN FOR HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. HIGHS TODAY WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID 60S FOR VALLEY AREAS...AND UPPER 50S TO LOW 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HRS ENDING 12Z/01 AT KPOU/KPSF/KALB/KGFL...AS AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. INTERVALS OF CLOUDS AT OR ABOVE 3500 FEET WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD WITH MORE SCATTERED CLOUDS THIS MORNING...AND BROKEN TO OVERCAST CLOUDS THIS AFTERNOON THROUGH TONIGHT. A VCSH GROUP WAS PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE CEILING AT KPSF COULD LOWER TO 2500 FEET AFTER 09Z. THE WINDS WILL BE LIGHT AND VARIABLE IN DIRECTION AT 3 KT OR LESS THROUGH MID MORNING. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 10 KT IN THE LATE MORNING THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THIS EVENING AND TONIGHT. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS/11 SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
927 AM EDT THU APR 30 2015 .SYNOPSIS... MOST AREAS WILL STAY DRY TODAY WITH SEASONABLE TEMPERATURES AND PARTIAL SUNSHINE. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 930 AM EDT...WEAK RIDGING IS CURRENTLY IN PLACE OVER OUR REGION. A CLOSED OFF SHORTWAVE TROUGH IS DIVING OUT OF THE GREAT LAKES...WHILE A SLOW MOVING CUTOFF LOW REMAINS WELL TO OUR EAST OVER THE WESTERN ATLANTIC OCEAN. MOSTLY SUNNY TO SUNNY CONDITIONS AND TEMPERATURES IN THE MID 40S TO LOWER 50S PREVAILED ACROSS THE REGION. MOST OF THE REGION IS EXPECTED TO REMAIN MOSTLY SUNNY THIS MORNING. THE SHORTWAVE TROUGH OVER THE GREAT LAKES LOOKS TO DIVE TOWARDS THE MID ATLANTIC STATES TODAY. IT SHOULD REMAIN FAR ENOUGH SOUTHWEST OF OUR AREA TO AVOID HAVING A DIRECT IMPACT...BUT MAY SEND SOME MID AND HIGH LEVEL CLOUDS INTO OUR AREA BY THIS AFTERNOON. MEANWHILE...BROAD N-NE FLOW AROUND THE OCEANIC CLOSED LOW WILL ALLOW SOME LOWER MOISTURE TO WORK ITS WAY INTO OUR REGION AS WELL. THIS MOISTURE...ALONG WITH DAYTIME HEATING...WILL ALLOW FOR SOME DIURNAL CU/STRAOTCU CLOUDS TO DEVELOP THIS AFTN. A STRAY SHOWER OR SPRINKLE IS POSSIBLE OVER THE HIGHER ELEVATIONS LATE TODAY...BUT WIDESPREAD PRECIP ISN/T EXPECTED DUE TO ONLY VERY WEAK BROAD SCALE LIFT IN PLACE. THE 12Z 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP THIS AFTN FOR HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. HIGHS TODAY WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID 60S FOR VALLEY AREAS...AND UPPER 50S TO LOW 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HRS ENDING 12Z/01 AT KPOU/KPSF/KALB/KGFL...AS AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. INTERVALS OF CLOUDS AT OR ABOVE 3500 FEET WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD WITH MORE SCATTERED CLOUDS THIS MORNING...AND BROKEN TO OVERCAST CLOUDS THIS AFTERNOON THROUGH TONIGHT. A VCSH GROUP WAS PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE CEILING AT KPSF COULD LOWER TO 2500 FEET AFTER 09Z. THE WINDS WILL BE LIGHT AND VARIABLE IN DIRECTION AT 3 KT OR LESS THROUGH MID MORNING. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 10 KT IN THE LATE MORNING THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THIS EVENING AND TONIGHT. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS/11 SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
702 AM EDT THU APR 30 2015 .SYNOPSIS... MOST AREAS WILL STAY DRY TODAY WITH SEASONABLE TEMPERATURES AND PARTIAL SUNSHINE. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 632 AM EDT...WEAK RIDGING IS CURRENTLY IN PLACE OVER OUR REGION. A CLOSED OFF SHORTWAVE TROUGH IS DIVING OUT OF THE GREAT LAKES...WHILE A SLOW MOVING CUTOFF LOW REMAINS WELL TO OUR EAST OVER THE WESTERN ATLANTIC OCEAN. IR SATELLITE IMAGERY SHOWS SUNNY SKIES OVER MUCH OF THE REGION WITH JUST A FEW THIN HIGH CIRRUS CLOUDS OVER WESTERN AREAS. MOST OF THE REGION LOOKS TO HAVE A MOSTLY SUNNY MORNING...ALLOWING FOR TEMPS TO WARM QUICKLY AFTER MORNING LOWS IN THE LOW 30S TO MID 40S. THE SHORTWAVE TROUGH OVER THE GREAT LAKES LOOKS TO DIVE TOWARDS THE MID ATLANTIC STATES TODAY. IT SHOULD REMAIN FAR ENOUGH SOUTHWEST OF OUR AREA TO AVOID HAVING A DIRECT IMPACT...BUT MAY SEND SOME MID AND HIGH LEVEL CLOUDS INTO OUR AREA BY THIS AFTERNOON. MEANWHILE...BROAD N-NE FLOW AROUND THE OCEANIC CLOSED LOW WILL ALLOW SOME LOWER MOISTURE TO WORK ITS WAY INTO OUR REGION AS WELL. THIS MOISTURE...ALONG WITH DAYTIME HEATING...WILL ALLOW FOR SOME DIURNAL CU/STRAOTCU CLOUDS TO DEVELOP THIS AFTN. A STRAY SHOWER OR SPRINKLE IS POSSIBLE OVER THE HIGHER ELEVATIONS LATE TODAY...BUT WIDESPREAD PRECIP ISN/T EXPECTED DUE TO ONLY VERY WEAK BROAD SCALE LIFT IN PLACE. THE 09Z 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP THIS AFTN FOR HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. HIGHS TODAY WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID 60S FOR VALLEY AREAS...AND UPPER 50S TO LOW 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /11Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HRS ENDING 12Z/01 AT KPOU/KPSF/KALB/KGFL...AS AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. INTERVALS OF CLOUDS AT OR ABOVE 3500 FEET WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD WITH MORE SCATTERED CLOUDS THIS MORNING...AND BROKEN TO OVERCAST CLOUDS THIS AFTERNOON THROUGH TONIGHT. A VCSH GROUP WAS PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE CEILING AT KPSF COULD LOWER TO 2500 FEET AFTER 09Z. THE WINDS WILL BE LIGHT AND VARIABLE IN DIRECTION AT 3 KT OR LESS THROUGH MID MORNING. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 10 KT IN THE LATE MORNING THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THIS EVENING AND TONIGHT. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
632 AM EDT THU APR 30 2015 .SYNOPSIS... MOST AREAS WILL STAY DRY TODAY WITH SEASONABLE TEMPERATURES AND PARTIAL SUNSHINE. SEVERAL NEARBY UPPER LEVEL DISTURBANCES WILL ALLOW FOR MORE CLOUDS ON FRIDAY...WITH A SLIGHT TO LOW CHANCE OF A RAIN SHOWER...WITH TEMPERATURES CONTINUING TO BE NEAR NORMAL LEVELS. EVEN WARMER TEMPERATURES ARE EXPECTED THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 632 AM EDT...WEAK RIDGING IS CURRENTLY IN PLACE OVER OUR REGION. A CLOSED OFF SHORTWAVE TROUGH IS DIVING OUT OF THE GREAT LAKES...WHILE A SLOW MOVING CUTOFF LOW REMAINS WELL TO OUR EAST OVER THE WESTERN ATLANTIC OCEAN. IR SATELLITE IMAGERY SHOWS SUNNY SKIES OVER MUCH OF THE REGION WITH JUST A FEW THIN HIGH CIRRUS CLOUDS OVER WESTERN AREAS. MOST OF THE REGION LOOKS TO HAVE A MOSTLY SUNNY MORNING...ALLOWING FOR TEMPS TO WARM QUICKLY AFTER MORNING LOWS IN THE LOW 30S TO MID 40S. THE SHORTWAVE TROUGH OVER THE GREAT LAKES LOOKS TO DIVE TOWARDS THE MID ATLANTIC STATES TODAY. IT SHOULD REMAIN FAR ENOUGH SOUTHWEST OF OUR AREA TO AVOID HAVING A DIRECT IMPACT...BUT MAY SEND SOME MID AND HIGH LEVEL CLOUDS INTO OUR AREA BY THIS AFTERNOON. MEANWHILE...BROAD N-NE FLOW AROUND THE OCEANIC CLOSED LOW WILL ALLOW SOME LOWER MOISTURE TO WORK ITS WAY INTO OUR REGION AS WELL. THIS MOISTURE...ALONG WITH DAYTIME HEATING...WILL ALLOW FOR SOME DIURNAL CU/STRAOTCU CLOUDS TO DEVELOP THIS AFTN. A STRAY SHOWER OR SPRINKLE IS POSSIBLE OVER THE HIGHER ELEVATIONS LATE TODAY...BUT WIDESPREAD PRECIP ISN/T EXPECTED DUE TO ONLY VERY WEAK BROAD SCALE LIFT IN PLACE. THE 09Z 3KM HRRR SHOWS JUST SOME VERY ISOLATED SPRINKLES/SHOWERS TRYING TO DEVELOP THIS AFTN FOR HIGH TERRAIN AREAS SUCH AS THE TACONICS AND BERKSHIRES...BUT WE WILL HAVE TO SEE IF THESE ACTUALLY DEVELOP INTO ANYTHING MEASURABLE. HIGHS TODAY WON/T BE AS WARM AS YESTERDAY SINCE MIXING WON/T BE QUITE AS DEEP. STILL...IT LOOKS SEASONABLE WITH MID 60S FOR VALLEY AREAS...AND UPPER 50S TO LOW 60S FOR HIGHER TERRAIN AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE SHORTWAVE DIVING INTO THE GREAT LAKES WILL HELP A SFC LOW DEVELOP ALONG THE CAROLINA COASTLINE TONIGHT...WHICH WILL THEN HEAD NORTHEAST AND OUT TO SEA ON FRIDAY. THIS SYSTEM WILL REMAIN WELL SOUTH OF OUR AREA...AND WON/T BE ABLE TO BRING WIDESPREAD PRECIP INTO OUR AREA. AS A RESULT...IT WILL BE MAINLY DRY THROUGH THE SHORT TERM PERIOD. HOWEVER...STILL CANNOT TOTALLY RULE OUT A BRIEF LIGHT SHOWER DUE TO WEAK TROUGH OVERHEAD BETWEEN TONIGHT AND FRIDAY...ESP FOR HIGH TERRAIN AREAS. ANY SHOWER WOULD BE RATHER LIGHT AND BRIEF IN DURATION. BY SATURDAY...UPPER LEVEL HEIGHTS START TO RISE...AS RIDGING BUILDS IN FROM THE OHIO VALLEY. CLOUD COVER WILL PROBABLY BE MOSTLY CLOUDY FOR TONIGHT AND FRIDAY DUE TO THE TROUGH OVERHEAD. HOWEVER...WITH BUILDING HEIGHTS AND WARMING TEMPS ALOFT...SKIES WILL BE PARTLY SUNNY FOR SATURDAY. TEMPS LOOK TO BE IN THE LOW TO MID 60S FOR VALLEY AREAS ON FRIDAY DUE TO THE CLOUD COVER IN PLACE...AND WILL PROBABLY REACH UPPER 60S TO LOW 70S FOR SATURDAY DUE TO MORE EXPECTED SUNSHINE AND WARMER TEMPS ALOFT. LOWS TONIGHT...FRIDAY AND SATURDAY NIGHTS WILL MAINLY BE IN THE 40S...ALTHOUGH SOME 30S ARE POSSIBLE IN HIGH TERRAIN AND OUTLYING AREAS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THERE IS A DECENT CONSENSUS FROM GUIDANCE THAT THE LAST BIT OF THE WESTERN PERIPHERY OF UPPER ENERGY TO OUR EAST WILL EXIT SUNDAY... WITH THE LAST OF ANY ISOLATED SHOWERS MOVING OUT OF WESTERN NEW ENGLAND. THE REGION WILL SEE INCREASING INFLUENCE OF FLAT UPPER RIDGING FROM THE WEST AND LOW LEVEL WARMING MONDAY AND TUESDAY. NORTHERN STREAM ENERGY IN CANADA WILL HELP UPPER HEIGHTS TO FALL AS THE UPPER RIDGING GETS SUPPRESSED SOUTHWARD. A WEAK COLD FRONT IS EXPECTED TO TRACK THROUGH TUESDAY AFTERNOON AND EVENING AS A RESULT OF THE LOWERING HEIGHTS OVER OUR REGION. THERE ARE SOME INDICATIONS OF A LITTLE BIT OF LOW LEVEL JET ENERGY AND SOME WEAK INSTABILITY THAT COULD SUPPORT SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. DEPENDING ON THE TIMING OF THE EXIT OF THE FRONT...A DRYING TREND IS EXPECTED WEDNESDAY. HIGHS SUNDAY IN THE 70S...WITH 60S IN HIGHER ELEVATIONS. HIGHS MONDAY AND TUESDAY IN THE MID TO UPPER 70S...NEAR 70 HIGHER ELEVATIONS. COULD FLIRT WITH 80 BY TUESDAY IN SOME PLACES DEPENDING ON EXTENT OF CLOUD COVER. HIGHS WEDNESDAY IN THE LOWER TO MID 70S...60S IN HIGHER ELEVATIONS. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HRS ENDING 06Z/01 AT KPOU/KPSF/KALB/KGFL...AS AN UPPER LEVEL LOW NEAR THE CANADIAN MARITIMES CONTINUES TO BRING SOME CLOUDS FROM EAST TO WEST OVER THE REGION. A FEW INSTABILITY LIGHT RAIN SHOWERS WILL ALSO BE POSSIBLE AROUND KGFL...KALB AND KPSF THIS EVENING. MID AND HIGH CLOUDS WILL MOVE FROM WESTERN NEW ENGLAND TO THE HUDSON RIVER VALLEY THROUGH THE PERIOD. SOME AREAS COULD SEE PERIODS OF CEILINGS AS LOW AS 4000-5000 FEET THIS AFTERNOON AND EVENING. A VCSH GROUP WAS ALSO PLACED IN THE KALB...KGFL AND KPSF TAFS THIS EVENING...BUT COVERAGE SHOULD BE ISOLATED TO SCATTERED AT BEST AND OF A SHOWERS WERE TO OCCUR...IT WOULD BE QUITE LIGHT...PROBABLY REMAINING VFR. THE WINDS WILL BE FROM THE N TO E AT LESS THAN 10 KT EARLY THIS MORNING THEN BECOME LIGHT AND VARIABLE IN DIRECTION AT 3 KT OR LESS BEFORE SUNRISE. THE WINDS WILL BE FROM THE NE TO SE AT LESS THAN 10 KT IN THE LATE MORNING THROUGH THE AFTERNOON...THEN AT LESS THAN 6 KT THIS EVENING. OUTLOOK... THURSDAY NIGHT-FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHC -SHRA. FRIDAY NIGHT-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ANOTHER WARM DAY IS EXPECTED TODAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY TO START...SOME CLOUDS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON HOURS. IT WILL PROBABLY NOT MIX QUITE AS DEEP AS YESTERDAY...SO DAYTIME TEMPS WILL LIKELY ONLY REACH MID 60S FOR VALLEY AREAS. RH VALUES LOOK TO FALL 30 TO 40 PERCENT FOR VALLEYS...AS 35 TO 45 PERCENT ACROSS THE HIGH TERRAIN. WITH WINDS FAIRLY LIGHT ALOFT...E-NE TODAY WILL ONLY BE ABOUT 5-10 MPH. RH WILL RECOVER TONIGHT 80 TO 100 PERCENT WITH SOME DEW FORMATION AND CALM WINDS. THERE IS THE SLIGHT CHANCE OF A SHOWER AS WELL. RH VALUES WILL DROP TO 35 TO 45 PERCENT BOTH FRIDAY AND SATURDAY AFTERNOONS WITH CONTINUED SEASONABLY WARM TEMPERATURES. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF A SHOWER...BUT MOST AREAS LOOK TO STAY COMPLETELY DRY...WITH A PARTLY TO MOSTLY CLOUDY SKY. WINDS BOTH DAYS WILL BE LIGHT...GENERALLY 5 MPH OR LESS FROM A N-NE DIRECTION ON FRIDAY...AND A N-NW DIRECTION ON SATURDAY. && .HYDROLOGY... NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT FIVE DAYS. ALTHOUGH THERE WILL BE SEVERAL UPPER LEVEL DISTURBANCES TRACKING CLOSE TO THE REGION OVER THE NEXT FEW DAYS...NONE WILL BE DIRECTLY IMPACTING THE AREA. ALTHOUGH A STRAY SHOWER OR TWO WILL BE POSSIBLE FOR TODAY THROUGH FRIDAY /MAINLY OVER HIGH TERRAIN AREAS/...MOST AREAS LOOK TO STAY DRY AND ANY RAIN SHOWERS WILL BE RATHER LIGHT AND BRIEF IN DURATION. MAINLY DRY WEATHER LOOKS TO OCCUR THIS WEEKEND INTO MONDAY...BEFORE A COLD FRONT RETURNS THE CHANCE FOR MORE WIDESPREAD SHOWERS TO THE REGION FOR TUESDAY. NOHRSC ANALYSIS SHOWS THAT ANY SNOWPACK THAT WOULD BE OF HYDROLOGIC SIGNIFICANCE HAS MELTED OUT OF THE ADIRONDACKS AND SRN GREENS...SO THE THREAT FOR SPRING FLOODING DUE TO SNOW/ICE HAS ENDED. 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 WEB SITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
921 AM EDT THU APR 30 2015 .SYNOPSIS... LOW PRESSURE NEAR THE COAST OF THE SOUTHEASTERN STATES WILL MOVE NORTHEASTWARD THOUGH FRIDAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND THE DEPARTING LOW FOR THE WEEKEND AND INTO EARLY NEXT WEEK. A COLD FRONT WILL APPROACH ON TUESDAY AND MAY STALL OVER OUR REGION BY THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 9:30 AM UPDATE: AN UPDATED LOOK AT MESOSCALE MODEL DATA SUCH AS THE RAP HRRR AND WRF-NMM SHOWS A SLIGHTLY LONGER WAIT TIME BEFORE ANY PRECIPITATION ARRIVES THIS AFTERNOON ACROSS THE SOUTHWESTERN PORTION OF THE CWA. ALSO, TEMPERATURES HAVE BEEN LOWERED BY SEVERAL DEGREES THIS MORNING AS THE RISE IN TEMPERATURE IS CONSIDERABLY SLOWER THAN YESTERDAY, LIKELY DUE TO A CHANGE OF AIRMASSES. MODELED 925 MB TEMPERATURES STILL SHOW THE POTENTIAL FOR HIGHS IN THE MID 60`S ON AVERAGE TODAY. PREVIOUS: AN UPR LOW NR THE GRTLKS WILL MOVE SEWD WHILE A SFC LOW OFF THE CAROLINA CST WILL MOVE TO THE NE AND EVENTUALLY E. BOTH OF THESE FEATURES WILL KEEP AN ABUNDANCE OF CLOUDS OVER THE REGION. AS HAS BEEN THE CASE FOR THE PAST FEW DAYS, THERE IS SOME DISAGREEMENT WRT PRECIP PLACEMENT, BUT THE BEST CHCS LOOK TO BE OVER THE LWR DELMARVA AND THEN NWWD INTO MD AND THE WRN PERIPHERY OF THE CWA. MOST LOCATIONS DO APPEAR TO BE DRY DURG THE DAY. THE GFS DOES CONTINUE IT`S WET BIAS, BRINGING SOME PRECIP UP HT I-95 CORRIDOR. IT CAN NOT BE RULED OUT, BUT FOR NOW WILL KEEP THINGS DRY. WITH A GUSTY E TO NE WIND, DESPITE TEMPS INTO THE UPPER 60S, WITH CLOUD COVER WIT WILL FEEL COOLER. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/... THE AFOREMENTIONED UPR LOW WILL BE ABOUT TO PASS OFF THE CST BY DAYBREAK FRI AND THIS WILL CAUSE THE SFC LOW TO MOVE EVEN FURTHER EWD WITH TIME. ONCE AGAIN, MOST, IF NOT ALL PRECIP SHOULD BE CONFINED TO THE LWR DELMARVA WITH MOST OTHER PLACES REMAINING CLOUDY AND DRY. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... COMPLEX PATTERN THROUGH THE WEEKEND ASSOCIATED WITH CUT-OFF, MID-LEVEL LOW INVOF THE MID-ATLANTIC. AS THIS FEATURE MOVES FURTHER OFFSHORE...FAIR WEATHER EXPECTED LATE IN THE WEEKND INTO EARLY NEXT WEEK...BEFORE A COLD FRONT APPROACHES EARLY NEXT WEEK. AS THE FLOW BECOMES PARALLEL TO THIS FEATURE, IT MAY STALL OVER THE MID-ATLANTIC BY THE MIDDLE OF THE WEEK. OVERALL...THE BEST CHANCE OF PRECIP WILL BE FRIDAY MORNING AND AGAIN DURING THE TUE-WED TIME FRAME...WITH TEMPERATURES GRADUALLY WARMING TO ABOVE NORMAL LEVELS BY EARLY NEXT WEEK. FRIDAY...EXPECTING A MOSTLY CLOUDY DAY AS LOW PRESSURE MOVES WELL TO OUR SOUTH. THERE IS SOME UNCERTAINTY AS TO HOW FAR NORTH HEAVIER PRECIP MAKES IT INTO THE DELMARVA...AS WELL AS JUST HOW QUICKLY IT MOVES OFFSHORE. THIS WILL BEAR WATCHING WITH A 2.0 INCH QPF BULLSEYE JUST OFFSHORE. ATTM...GENERALLY LIGHT QPF IN THE FORECAST W/AMOUNTS GENERALLY UNDER 0.5 INCH CONFINED TO THE DELMARVA. COULD CERTAINLY SEE PRECIP LINGER LONGER INTO THE DAY ON FRIDAY IF THIS SYSTEM SLOWS A BIT. WITH HIGH PRESSURE TO THE NORTH...THERE WILL ALSO BE A TIGHT GRADIENT OVER THE AREA...WITH WIND GUSTS UP TO 30 KTS ALONG THE COAST OUT OF THE NORTHEAST. A COOL DAY WITH ONSHORE FLOW. SATURDAY...S/WV DISTURBANCE MOVES SOUTHWARD ALONG THE BACK- SIDE OF DEPARTING MID-LEVEL, CUTOFF LOW. THERE IS SUFFICIENT LOW-LEVEL MOISTURE...ALONG WITH A SURFACE TROUGH...SO -SHRA ARE POSSIBLE. WITH THE MID-LEVEL LOW NEARBY..CANNOT RULE OUT ISOLATED -TSRA...BUT LEFT MENTION OUT OF THE FORECAST FOR NOW AS STABILITY INDICES ARE MARGINAL AT BEST. SUNDAY...EXPECTING GENERALLY FAIR WEATHER WITH TEMPERATURES NEAR SEASONABLE LEVELS. STILL CANNOT RULE OUT AN ISOLATED -SHRA...BUT NOT BUYING THE GFS QPF...WHICH APPEARS OVERDONE. MONDAY...ANOTHER FAIR WEATHER DAY WITH A DRY WARM FRONTAL PASSAGE EXPECTED. ABOVE NORMAL HIGH TEMPERATURES...COOLER NEAR THE COAST IN A SOUTHERLY FLOW. MONDAY NIGHT THRU WEDNESDAY...A COLD FRONT APPROACHES THE REGION...W/THE MID-LEVEL FLOW GRADUALLY BECOMING PARALLEL TO THIS FEATURE...WHICH MAY STALL OVER THE REGION BY MID- WEEK. THIS LEADS TO UNCERTAINTY IN POPS AND TEMPS DURING THIS TIME FRAME. && .AVIATION /13Z THURSDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS WILL PREVAIL AT THE TAF SITES THU THE DAY TODAY AND AT MOST SITES TONIGHT. HOWEVER, AT KMIV AND KACY, SOME MVFR IS FCST TWD THE END OF THE PD. CONFIDENCE IS LWR THAN AVERAGE ON THE MVFR CONDS. AN UPR LOW NR THE GRTLKS WILL MOVE SEWD THRU TONIGHT AND BE LOCATED IN NC BY DAYBREAK FRI. A SFC LOW WILL FORM NR THE CAROLINAS AND MOVE NEWD THEN EWD. SOME PRECIP IS PSBL MAINLY S OF THE TAF SITES, BUT THE BEST CHCS WUD BE AT KMIV AND KACY. FOR NOW WILL LEAVE OUT OF THE INDIVIDUAL FCSTS. A GUSTY E TO NE WIND WILL DEVELOP DURG THE DAY AND CUD GUST AS HIGH AS 20 KT. THE GUSTINESS SHUD DECREASE AFTER SUNSET BUT MAY LINGER AT KMIV AND KACY. OUTLOOK... FRI AND SAT...MVFR POSSIBLE IN SHRA...OTHERWISE VFR EXPECTED. WINDS MAY GUST TO 25 KNOTS OUT OF THE NORTHEAST ON FRI. SUN AND MON...VFR EXPECTED. && .MARINE... THE SCA HEADLINE WILL REMAIN IN PLACE UNCHANGED AS NELY FLOW DEVELOPS AND INCREASES. THE WIND CUD GUST TO 30 KT AND SEAS WILL INCREASE TO AROUND 7 FT. OUTLOOK.. FRI AND FRI NIGHT...WINDS AND SEAS WILL GRADUALLY SUBSIDE BELOW SCA THRESHOLDS FRIDAY EVENING. SAT THRU MON...WINDS AND SEAS EXPECTED TO REMAIN BLW SCA CRITERIA. && .TIDES/COASTAL FLOODING... WITH THE FULL MOON ON SATURDAY, ASTRONOMICAL HIGH TIDES BY FRIDAY WILL ALREADY BE NEAR MEAN HIGHER HIGH WATER. THEREFORE, DEPENDING ON HOW CLOSE THE COASTAL LOW TRACKS TO OUR REGION, THERE IS A CHANCE FOR MINOR TIDAL FLOODING WITH THE HIGH TIDE CYCLE DURING THE DAY ON FRIDAY. THIS IS VERY DEPENDENT ON THE TRACK OF THE LOW, AND AT THIS POINT, THE GFS HAS BEEN TRENDING FURTHER EAST WITH THE TRACK, CLOSER TO THE ECMWF. THE FURTHER EAST THE TRACK IS, THE LESS OF AN IMPACT FOR OUR REGION. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 PM EDT FRIDAY FOR ANZ431-450>455. && $$ SYNOPSIS...FRANCK NEAR TERM...GAINES/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...FRANCK AVIATION...FRANCK/NIERENBERG MARINE...FRANCK/NIERENBERG TIDES/COASTAL FLOODING...
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
938 AM EDT THU APR 30 2015 .DISCUSSION... CURRENT...LATE SEASON FRONTAL PASSAGE IS MAKING PROGRESS SOUTHWARD THROUGH THE AREA. THE BOUNDARY WILL PASS THROUGH THE REMAINDER OF THE TREASURE COAST VEERING WSW/W WINDS TO NW. SOME SPRINKLES MAY BE ASSOCIATED WITH CLEARING LOWER CLOUDS MAINLY DURING THE MORNING BEFORE DEEPER DRYING WORKS SOUTHWARD BEHIND THE FRONTAL PASSAGE THIS AFTERNOON. WINDS DURING THIS AFTERNOON WILL APPROACH 15 MPH WITH SOME GUSTS TO 20 MPH BEFORE TAPERING OFF WITH LOSS OF POST FRONTAL GRADIENT AND AFTERNOON MIXING. LOCAL HRRR GUID SHOWS DEVELOPMENT OF AN MID AFTERNOON SEABREEZE VEERING WINDS TO THE NORTHEAST ALONG THE IMMEDIATE CST. TIMING OF THIS ONSHORE WIND WL DEPEND ON HOW QUICKLY CLOUD COVERAGE DIMINISHES. && .AVIATION...SOME MORNING STRATUS (IFR) TO PLAGUE TERMINALS ALONG THE I-4 CORRIDOR PAST SUNRISE BEFORE BURNING OFF BY AROUND 11 AM. DRIER AIR WILL MOVE INTO THE AREA FROM THE NORTH TODAY BEHIND LATEST WEAK FRONTAL TROUGH. A FEW SPRINKLES ACROSS NORTHERN TERMINALS MAY BE POSSIBLE THROUGH MIDDAY. VFR CONDS PAST MIDDAY. && .MARINE...CURRENT-TONIGHT...THE FRONTAL BOUNDARY WILL PRESS SOUTHWARD ACROSS ALL THE WATERS BY EARLY AFTERNOON. WINDS WILL VEER TO NW WHILE INCREASING TO 15-20 KTS BY EARLY AFTERNOON FOR WELL OFFSHORE. CAUTIONARY STATEMENTS OFFSHORE FOR WINDS. SEAS 2-4 FT NEAR SHORE AND 4-5 FT OFFSHORE. WAVE HEIGHTS WILL FALL BACK TO 3-4 FT AREAWIDE THIS EVENING AND OVERNIGHT. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ JP/ALM
AREA FORECAST DISCUSSION
NWS MIAMI FL
158 AM EDT THU APR 30 2015 .AVIATION... WESTERLY WINDS WILL PREVAIL THROUGH THE FORECAST PERIOD. REGIONAL WINDS FORECAST TO BE IN THE 10 TO 15 KNOT RANGE AROUND 13-15Z THEN SLOWLY DECREASING TO AROUND 10 KNOTS AROUND 18-20Z. REGIONAL OBSERVATIONS INDICATE LINGERING LOW LEVEL STRATUS EARLY THIS MORNING. FOR ALL TERMINALS THERE COULD BE BRIEF MVFR CEILINGS AND VERY BRIEF IFR CEILINGS FROM TIME TO TIME. WILL AMEND IF/AS NECESSARY. 60 && .PREV DISCUSSION... /ISSUED 751 PM EDT WED APR 29 2015/ UPDATE... THE MAIN SHIELD OF RAIN HAS PUSHED WELL OFF TO THE SOUTH AND THERE WILL BE JUST A SLIGHT CHANCE OF SHOWERS TONIGHT MAINLY OVER THE ATLANTIC AND GULF WATERS. DRIER AIR IS EXPECTED TO MOVE INTO THE REGION LATER TONIGHT INTO TOMORROW AS A COLD FRONT MOVES THROUGH THE REGION. PLEASANT CONDITIONS ARE EXPECTED TO LAST INTO THE WEEKEND AS TEMPERATURES RISE INTO THE LOWER TO MID 80S ON SATURDAY AND SUNDAY AFTERNOON. PREV DISCUSSION... /ISSUED 736 PM EDT WED APR 29 2015/ AVIATION... THE WINDS WILL REMAIN SOUTHWEST TONIGHT OVER THE TAF SITES WITH SPEEDS DECREASING FROM AROUND 10 KNOTS THIS EVENING TO AROUND 5 KNOTS LATE TONIGHT. THE WEATHER SHOULD REMAIN DRY OVER MOST OF THE TAF SITES TONIGHT...EXCEPT FOR KPBI WHERE THERE COULD BE A FEW SHOWERS UNTIL 02Z. THEREFORE...VCSH WILL CONTINUE AT KPBI TAF SITE UNTIL 02Z THEN GO DRY FOR REST OF TONIGHT. THE VIS SHOULD REMAIN IN THE VFR CONDITIONS TONIGHT AT ALL OF THE TAF SITES. HOWEVER...THE CEILING COULD FALL INTO THE MVFR CONDITIONS FOR AN HOUR OR TWO THIS EVENING BUT THEN BECOME VFR FOR LATE TONIGHT. AVIATION...54/BNB PREV DISCUSSION... /ISSUED 252 PM EDT WED APR 29 2015/ DISCUSSION... MAIN CONCERN THIS AFTERNOON IS THE POTENTIAL FOR ADDITIONAL CONVECTION OUT AHEAD OF AN APPROACHING COLD FRONT. LATEST VISIBLE SATELLITE STILL SHOWS QUITE A BIT OF DEBRIS CLOUDINESS ACROSS VIRTUALLY ALL OF SOUTH FLORIDA. POCKETS OF CLEARING HAVE SHOWN BRIEFLY ACROSS THE LAKE OKEECHOBEE AREA WHERE ARE A FEW SHOWERS HAVE DEVELOPED. THE DEBRIS CLOUDS ARE THE RESULT OF CONTINUING CONVECTION ACROSS THE KEYS DUE TO A WEAK SURFACE TROUGH. THE COLD FRONT IS STILL PROGGED TO PUSH THROUGH THE AREA LATER THIS EVENING WITH A SLIGHT POSSIBILITY OF ADDITIONAL ORGANIZED SHOWERS AND THUNDERSTORMS OUT AHEAD OF IT...BUT THE THREAT IS LOOKING LESS LIKELY. THE LATEST HRRR WHICH HAS INITIALIZED WELL THROUGH THE MORNING KEEPS THE AREA NEARLY RAIN FREE LATER THIS EVENING. THE AFOREMENTIONED COLD FRONT SHOULD THEN CLEAR THE AREA OVERNIGHT TONIGHT AND INTO THURSDAY TAKING VIRTUALLY ALL OF THE PRECIPITATION WITH IT. BY FRIDAY MORNING...ANOTHER COLD BUT DRY FRONT WILL SURGE INTO SOUTH FLORIDA FROM THE NORTH AS AN H5 TROUGH IS STILL EXPECTED TO DIG SOUTH AND INTO THE CAROLINAS. THIS WILL BRING A MUCH COOLER AND DRIER AIR MASS INTO THE AREA FOR FRIDAY THROUGH SATURDAY. MOST MODEL BLENDS ARE DEPICTING DEWPOINTS IN THE UPPER 50S ACROSS THE EAST COAST METRO AREAS FRIDAY INTO SATURDAY WHICH WILL MAKE FOR VERY PLEASANT CONDITIONS. HIGH PRESSURE BEHIND THE DRY FRONT IS THEN EXPECTED TO QUICKLY PUSH TO THE EAST AND INTO THE WESTERN ATLANTIC. THIS WILL ALLOW FOR A MORE EASTERLY FLOW REGIME TO PREVAIL SUNDAY THROUGH MONDAY. DEEPER MOISTURE WILL THEN RETURN FOR THE FIRST PART OF NEXT WEEK AS MODELS DEPICT AN AREA OF LOW PRESSURE DEVELOPING ACROSS THE YUCATAN CHANNEL AND PUSHING TO THE NORTHEAST AND TOWARD THE BAHAMAS. THIS WILL RETURN DECENT CHANCES FOR SHOWERS AND POSSIBLE THUNDERSTORMS THROUGH MIDWEEK. AVIATION... CLOUDS ARE STILL DRIFTING FROM THE GULF OF MEXICO INTO THE SOUTHERN PORTIONS OF THE CWA. VCSH IS INCLUDED FOR ALL AIRPORTS UNTIL 00Z APR 30. WINDS WILL SHIFT FROM 220 TO 280 AS THE FRONT CONTINUES TO APPROACH FROM THE WEST. THE CLOUD COVER IS NOT ALLOWING FOR SURFACE HEATING. WITHOUT SURFACE HEATING AND THE LOW LEVEL COOLING FROM THE RAINS EARLIER, THUNDERSTORMS ARE NOT VERY LIKELY THIS EVENING. HOWEVER, WE WILL AMEND THE TAFS AS NEEDED. MARINE... SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WILL CONTINUE TO AFFECT THE ATLANTIC WATERS OF BROWARD AND MIAMI-DADE COUNTY THIS AFTERNOON. SOUTHWESTERLY WINDS AHEAD OF A COLD FRONT WILL INCREASE ACROSS THE ATLANTIC WATERS TO NEAR SCA CRITERIA...WILL HOLD OFF FOR NOW AND COVER WITH SCEC. WINDS WILL THEN TURN MORE NORTHWEST OVERNIGHT AND INTO THURSDAY AS THE COLD FRONT PUSHES THROUGH THE AREA. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 84 66 85 65 / 10 10 0 0 FORT LAUDERDALE 84 67 85 69 / 10 10 0 0 MIAMI 85 67 86 68 / 20 10 10 0 NAPLES 82 67 83 62 / 10 0 0 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...23/SK LONG TERM....23/SK AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1146 PM CDT WED APR 29 2015 .UPDATE... ISSUED AT 853 PM CDT WED APR 29 2015 UPPER-LEVEL LOW CONTINUES TO DIVE SLOWLY SOUTH THROUGH THE WESTERN GREAT LAKES REGION. SHOWERS IN ADVANCE OF THIS FEATURE ARE ABOUT AS WIDESPREAD AS THEY HAVE BEEN, WHICH IS NOT SAYING MUCH, AND WILL BRING SPOTTY LIGHT SHOWERS OR SPRINKLES TO THE EASTERN 2/3 OR SO OF THE FORECAST AREA FOR THE NEXT SEVERAL HOURS. HOWEVER, DO NOT EXPECT MUCH IN THE WAY OF MEASURABLE RAINFALL ACROSS CENTRAL AND SOUTHEAST IL. GOING FORECAST WAS IN REASONABLE SHAPE OVERALL, BUT HAVE UPDATED FOR THE LATEST OVERNIGHT TRENDS. THE MOST NOTABLE CHANGE WAS TO DECREASE THE ALREADY LOW POPS A BIT MORE BASED ON RADAR TRENDS. && .SHORT TERM...(TONIGHT) ISSUED AT 243 PM CDT WED APR 29 2015 AN UPPER LEVEL LOW WAS OVER EASTERN LAKE SUPERIOR THIS AFTERNOON WITH ANOTHER UPPER LEVEL LOW OVER SOUTHEAST MO. THE UPPER LEVEL LOW OVER EASTERN LAKE SUPERIOR WILL TRACK SOUTHWARD INTO EAST CENTRAL INDIANA BY NOON THU AND TO BE THE DOMINANT WEATHER SYSTEM TO AFFECT CENTRAL/SE IL NEXT 24 HOURS ESPECIALLY EASTERN IL. SCATTERED TO BROKEN HIGH BASED CUMULUS CLOUDS 7-9K FT WEST OF HIGHWAY 51 WILL CONTINUE TO INCREASE OVER EASTERN IL REST OF TODAY. AS NEXT SHORT WAVE DROPS SOUTHWARD, SHORT RANGE MODELS LIKE HRRR AND RAP DEVELOP ISOLATED CONVECTION OVER CENTRAL IL LATE THIS AFTERNOON AND EARLY EVENING AND SHIFT IT SE LATER THIS EVENING AND OVERNIGHT. CONTINUE 20-30% CHANCES OF SHOWERS THIS EVENING (ISOLATED THUNDER NORTH OF I- 72 UNTIL SUNSET) AND ISOLATED SHOWERS EAST OF I-55 OVERNIGHT. LACK OF MOISTURE WILL KEEP RAINFALL AMOUNTS LIGHT (LESS THAN A TENTH INCH) IF THEY HAPPEN. LOWS OVERNIGHT RANGE FROM LOWER 40S FROM LINCOLN NORTH TO THE UPPER 40S SE OF I-70. NNE WINDS OF 5-10 MPH TONIGHT WITH NO FOG EXPECTED TONIGHT. .LONG TERM...(THURSDAY THROUGH WEDNESDAY) ISSUED AT 243 PM CDT WED APR 29 2015 UPPER LEVEL LOW WILL CONTINUE TO TRACK SOUTH, EAST OF THE AREA, WHICH WILL KEEP THE SURFACE RIDGE TO THE WEST OF THE CWA THURSDAY, KEEPING US WITH NORTHERLY SURFACE WINDS. WILL KEEP A SLIGHT CHANCE OF ISOLATED SHOWERS IN THE EAST FOR THURSDAY AS THE UPPER LOW MOVES SOUTH. ONCE THAT PASSES THURSDAY EVENING DRY WEATHER IS EXPECTED BEGINNING FRIDAY. THE HIGH PRESSURE RIDGE WILL THEN MOVE ACROSS THE AREA FRIDAY WITH DRY WEATHER AND LIGHT WINDS. THIS RIDGE WILL DROP SOUTH OF THE AREA FRIDAY NIGHT AND REMAIN THERE FOR SATURDAY. HOWEVER, NORTHWEST FLOW WILL REMAIN OVER THE AREA INTO THE WEEKEND. A COUPLE OF WEAK WAVES WILL MOVE SOUTHEAST THROUGH THE NORTHWEST FLOW. ANY PCPN ASSOCIATED WITH THESE WAVES SHOULD REMAIN WEST OF THE AREA AT LEAST THROUGH SATURDAY. TEMPS THROUGH THE PERIOD WILL RANGE FROM AROUND NORMAL FOR THURSDAY TO ABOVE NORMAL FOR FRIDAY AND SATURDAY. THE HIGH PRESSURE RIDGE WILL SLIDE INTO THE SOUTHEAST US BY SATURDAY NIGHT, WHICH WILL ALLOW THE UPPER LEVEL FLOW TO BEGIN TO TRANSITION TO A MORE ZONAL PATTER FOR THE WEEKEND. THIS WILL ALSO ALLOW SOUTHERLY WINDS TO RETURN TO THE CWA, BRINGING AN INCREASE IN MOISTURE AND TEMPERATURES. IN ADDITION, ANY PCPN ASSOCIATED WITH ADDITIONAL WEAK MID LEVEL WAVES WILL HOLD TOGETHER LONGER AND BE ABLE TO REACH INTO THE CWA. SO WILL KEEP THE POPS IN THE FORECAST BEGINNING SATURDAY NIGHT AND CONTINUING THROUGH THE WEEKEND AND INTO NEXT WEEK. WITH THE FLOW BECOMING ZONAL ANY SURFACE FRONT WILL BECOME SOMEWHAT STATIONARY OVER THE MIDDLE OF THE CWA THROUGH THE FIRST PART OF THE WEEK. WITH THE INCREASED MOISTURE, IT LOOKS LIKE LIKELY POPS IS WARRANTED FOR THE NORTHERN PARTS OF THE CWA, WITH CHANCE POPS TO THE SOUTH, AND EITHER NO POPS OR SLIGHT CHANCE POPS IN THE SOUTHEAST. TEMPS WILL BECOME WARMER, ESPECIALLY IN THE SOUTHERN HALF OF THE CWA, WHICH SHOULD BE SOUTH OF THE STATIONARY FRONT THROUGH PART OF THE WEEK. ABOVE NORMAL TEMPS CAN BE EXPECTED WITH THIS PATTERN. BELIEVE GUIDANCE IS A LITTLE ON THE WARM SIDE FOR DAYTIME HIGHS, ESPECIALLY IN AREAS WHERE THERE WILL BE PCPN AND CLOUDS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1141 PM CDT WED APR 29 2015 SCATTERED LIGHT SHOWERS/SPRINKLES CONTINUE TO IMPACT THE CENTRAL ILLINOIS TERMINALS THIS EVENING AS AN UPPER LEVEL DISTURBANCE DIVES SOUTH ACROSS THE AREA FROM THE GREAT LAKES REGION. THESE SHOWERS AND ASSOCIATED VFR CIGS NOW APPEAR LIKELY TO HANG ON FOR SEVERAL MORE HOURS, LONGER THAN WAS PREVIOUSLY EXPECTED. EVENTUALLY, SKIES SHOULD CLEAR TOWARD THURSDAY MORNING, ALTHOUGH SOME ADDITIONAL CIGS MY DEVELOP WITH DAYTIME HEATING, ESPECIALLY OVER TOWARD KCMI. NORTHERLY WINDS WILL PREVAIL THROUGH THE PERIOD, BECOMING GUSTY AT TIMES DURING THE DAYTIME HOURS THURSDAY DURING PEAK MIXING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...BAK SHORT TERM...07 LONG TERM...AUTEN AVIATION...BAK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
241 PM EDT THU APR 30 2015 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 225 AM EDT THU APR 30 2015 AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WISCONSIN WILL PUSH ACROSS INDIANA TODAY. THIS WILL RESULT IN SOME CLOUDS ALONG WITH CHANCES FOR A FEW RAIN SHOWERS AND ISOLATED THUNDERSTORMS. THE UPPER LOW WILL DEPART TONIGHT...ALLOWING HIGH PRESSURE TO BUILD ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS WILL BRING DRY AND PLEASANT WEATHER TO CENTRAL INDIANA FOR THE START OF WEEKEND. CHANCE FOR RAIN WILL RETURN TO CENTRAL INDIANA BY SUNDAY AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY APPROACHES THE AREA ALONG WITH WARMER AND MORE HUMID AIR. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1006 AM EDT THU APR 30 2015 CENTER OF THE UPPER LEVEL LOW CURRENTLY LOCATED OVER SOUTHWEST LOWER MICHIGAN WITH FORCING ALOFT EXTENDING SOUTH INTO THE REGION. SEEING A MIX OF CLOUDS WITH POCKETS OF LIGHT SHOWERS AS WELL. TEMPS AS OF 14Z GENERALLY RANGED FROM THE UPPER 40S TO MID 50S. THE UPPER LOW WILL TRACK SOUTHEAST ACROSS THE AREA THROUGH THE AFTERNOON...MAINTAINING UNSETTLED WEATHER WITH SCATTERED CLOUDS AND PRECIP. RAP DATA SHOWING VERY COLD AIR ALOFT ASSOCIATED WITH THIS SYSTEM...ON THE ORDER OF -27 TO -29C AT 500MB. PRESENCE OF THE VERY COLD AIR WILL ENABLE CLOUDS TO EXPAND INTO COVERAGE INTO THE AFTERNOON...AS WELL AS PROMOTE SHOWERS AND ISOLATED CONVECTION. AXIS OF 100-300 J/KG CAPE IN THE HAIL GROWTH LAYER SETTING UP OVER SOUTHEAST HALF OF THE FORECAST AREA THIS AFTERNOON. COMBINED WITH IMPRESSIVE LAPSE RATES IN THE LOWER LEVELS...EXPECT A FEW LIGHTNING STRIKES WITHIN SOME OF THE STRONGER CELLS. WILL INTRODUCE ISOLATED THUNDER MAINLY ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY METRO-MUNCIE LINE. GRAUPEL AND OR SMALL HAIL WILL ALSO BE A POSSIBILITY WITH ANY STRONGER CELL AS WET BULB ZERO LEVELS PROGGED AT 3500-4000FT FOR MUCH OF THE AFTERNOON. PRECIP WILL DIMINISH FROM NORTH TO SOUTH LATE THIS AFTERNOON AS THE UPPER LOW TRACKS INTO NORTHERN KENTUCKY AND INSTABILITY IS LOST. BASED ON MODEL SOUNDINGS...BROUGHT IN WIND GUSTS TO 20-25MPH FOR THE AFTERNOON AS WELL. EXPECT HIGHS MAINLY IN THE MID/UPPER 50S...POSSIBLY LOWER 60S OVER FAR SOUTHERN COUNTIES. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... ISSUED AT 225 AM EDT THU APR 30 2015 MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS. GFS AND NAM BOTH AGREE THAT THE UPPER LOW WILL QUICKLY DEPART THIS EVENING...AND ALONG WITH THE LOSS OF DAYTIME HEATING...AND THE MINIMAL CHANCE FOR SHOWERS TO BEGIN WITH WILL DIMINISH TO NIL. GFS AND NAM THEN ALLOW THE STRONG RIDGE THAT IS IN PLACE OVER THE WESTERN PLAINS TO BUILD EAST ACROSS INDIANA AND THE GREAT LAKES. FORECAST SOUNDINGS ALSO DRY OUT AS HIGH PRESSURE BUILDS ACROSS THE AREA THROUGH THIS PERIOD. THUS WILL TREND TOWARD MOSTLY CLEAR NIGHT AND MOSTLY SUNNY DAYS. AS THE UPPER LOW DEPARTS TONIGHT WARM AIR ADVECTION BEGINS TONIGHT AS THE DOME OF COLD AIR ASSOCIATED WITH THE UPPER LOW DEPARTS. GIVEN THIS WILL TREND TONIGHTS LOWS TOWARD THE WARMER MAVMOS. SUBTLE WARM AIR ADVECTION PATTERN CONTINUES ON FRIDAY INTO SATURDAY AS 850MB TEMPS REACH NEAR 7C BY SAT. WILL TREND HIGHS WITH A SLOWLY GRADUAL WARMING TREND. A MAVMOS/METMOS BLEND SHOULD WORK FINE THERE. && .LONG TERM /SUNDAY NIGHT THROUGH NEXT THURSDAY/... ISSUED AT 240 PM EDT THU APR 30 2015 ENSEMBLES INDICATE INITIALLY ZONAL FLOW EARLY NEXT WEEK WILL AMPLIFY BY THE MIDDLE OF NEXT WEEK AS MEAN TROUGHING DEVELOPS OVER THE WESTERN STATES AND UPPER RIDGING BUILDS INTO THE SOUTHEAST PARTS OF THE COUNTRY. ENSEMBLES SUGGEST THERE MAY A THREAT FOR SHOWERS AND THUNDERSTORMS OVER AT LEAST PARTS OF THE AREA THROUGHOUT THE EXTENDED PERIOD AS A FRONTAL SYSTEM POTENTIALLY GETS HUNG UP NEARBY. MAY END UP BEING SOME DRY PERIODS...BUT FOR NOW WILL BROADBRUSH POPS THROUGHOUT THE PERIOD. && .AVIATION /DISCUSSION FOR THE 301800Z TAFS/... ISSUED AT 1234 PM EDT THU APR 30 2015 THREAT FOR SCATTERED SHOWERS/ISOLATED LIGHTNING STRIKES WILL CONTINUE IN THE VICINITY OF THE TAF SITES THROUGH ABOUT 010000Z AS A VORTICITY LOBE DROPS SOUTH THROUGH THE LOCAL AREA. POTENTIAL FOR ANY DIRECT IMPACTS TOO LOW TO MENTION IN THE FORECAST AT THIS TIME. OTHERWISE...DIURNAL CLOUD BASES AROUND 040 WITH LAYERED CLOUDS ABOVE EXPECTED TO THIN OUT TOWARDS/AFTER SUNSET WITH LOSS OF HEATING AND PASSAGE OF VORTICITY LOBE. OCCASIONAL SURFACE WIND GUSTS AROUND 20 KTS FROM 340-010 DEGREES THIS AFTERNOON SHOULD DIMINISH WITH SUNSET. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....JAS AVIATION...JAS VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1234 PM EDT THU APR 30 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 225 AM EDT THU APR 30 2015 AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WISCONSIN WILL PUSH ACROSS INDIANA TODAY. THIS WILL RESULT IN SOME CLOUDS ALONG WITH CHANCES FOR A FEW RAIN SHOWERS AND ISOLATED THUNDERSTORMS. THE UPPER LOW WILL DEPART TONIGHT...ALLOWING HIGH PRESSURE TO BUILD ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS WILL BRING DRY AND PLEASANT WEATHER TO CENTRAL INDIANA FOR THE START OF WEEKEND. CHANCE FOR RAIN WILL RETURN TO CENTRAL INDIANA BY SUNDAY AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY APPROACHES THE AREA ALONG WITH WARMER AND MORE HUMID AIR. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1006 AM EDT THU APR 30 2015 CENTER OF THE UPPER LEVEL LOW CURRENTLY LOCATED OVER SOUTHWEST LOWER MICHIGAN WITH FORCING ALOFT EXTENDING SOUTH INTO THE REGION. SEEING A MIX OF CLOUDS WITH POCKETS OF LIGHT SHOWERS AS WELL. TEMPS AS OF 14Z GENERALLY RANGED FROM THE UPPER 40S TO MID 50S. THE UPPER LOW WILL TRACK SOUTHEAST ACROSS THE AREA THROUGH THE AFTERNOON...MAINTAINING UNSETTLED WEATHER WITH SCATTERED CLOUDS AND PRECIP. RAP DATA SHOWING VERY COLD AIR ALOFT ASSOCIATED WITH THIS SYSTEM...ON THE ORDER OF -27 TO -29C AT 500MB. PRESENCE OF THE VERY COLD AIR WILL ENABLE CLOUDS TO EXPAND INTO COVERAGE INTO THE AFTERNOON...AS WELL AS PROMOTE SHOWERS AND ISOLATED CONVECTION. AXIS OF 100-300 J/KG CAPE IN THE HAIL GROWTH LAYER SETTING UP OVER SOUTHEAST HALF OF THE FORECAST AREA THIS AFTERNOON. COMBINED WITH IMPRESSIVE LAPSE RATES IN THE LOWER LEVELS...EXPECT A FEW LIGHTNING STRIKES WITHIN SOME OF THE STRONGER CELLS. WILL INTRODUCE ISOLATED THUNDER MAINLY ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY METRO-MUNCIE LINE. GRAUPEL AND OR SMALL HAIL WILL ALSO BE A POSSIBILITY WITH ANY STRONGER CELL AS WET BULB ZERO LEVELS PROGGED AT 3500-4000FT FOR MUCH OF THE AFTERNOON. PRECIP WILL DIMINISH FROM NORTH TO SOUTH LATE THIS AFTERNOON AS THE UPPER LOW TRACKS INTO NORTHERN KENTUCKY AND INSTABILITY IS LOST. BASED ON MODEL SOUNDINGS...BROUGHT IN WIND GUSTS TO 20-25MPH FOR THE AFTERNOON AS WELL. EXPECT HIGHS MAINLY IN THE MID/UPPER 50S...POSSIBLY LOWER 60S OVER FAR SOUTHERN COUNTIES. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... ISSUED AT 225 AM EDT THU APR 30 2015 MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS. GFS AND NAM BOTH AGREE THAT THE UPPER LOW WILL QUICKLY DEPART THIS EVENING...AND ALONG WITH THE LOSS OF DAYTIME HEATING...AND THE MINIMAL CHANCE FOR SHOWERS TO BEGIN WITH WILL DIMINISH TO NIL. GFS AND NAM THEN ALLOW THE STRONG RIDGE THAT IS IN PLACE OVER THE WESTERN PLAINS TO BUILD EAST ACROSS INDIANA AND THE GREAT LAKES. FORECAST SOUNDINGS ALSO DRY OUT AS HIGH PRESSURE BUILDS ACROSS THE AREA THROUGH THIS PERIOD. THUS WILL TREND TOWARD MOSTLY CLEAR NIGHT AND MOSTLY SUNNY DAYS. AS THE UPPER LOW DEPARTS TONIGHT WARM AIR ADVECTION BEGINS TONIGHT AS THE DOME OF COLD AIR ASSOCIATED WITH THE UPPER LOW DEPARTS. GIVEN THIS WILL TREND TONIGHTS LOWS TOWARD THE WARMER MAVMOS. SUBTLE WARM AIR ADVECTION PATTERN CONTINUES ON FRIDAY INTO SATURDAY AS 850MB TEMPS REACH NEAR 7C BY SAT. WILL TREND HIGHS WITH A SLOWLY GRADUAL WARMING TREND. A MAVMOS/METMOS BLEND SHOULD WORK FINE THERE. && .LONG TERM /SUNDAY THROUGH WEDNESDAY NIGHT/... ISSUED AT 318 AM EDT THU APR 30 2015 A WARMER AND SLIGHTLY MORE HUMID AIRMASS WILL BE IN PLACE FOR THE LONG TERM PERIOD AS A WARM FRONT ENTERS THE LOWER MIDWEST. HOWEVER...WITHOUT ANY SIGNIFICANT LIFTING MECHANISMS AND RIDGING ALOFT...SHOWER AND THUNDERSTORM CHANCES WILL BE LOW. MOST CONVECTIVE ACTIVITY WILL BE DIURNALLY DRIVEN. CHANCES WILL INCREASE SLIGHTLY ON TUESDAY NIGHT THOUGH AS A COLD FRONT MOVES ACROSS CENTRAL INDIANA. AS THIS FRONT STALLS OUT AND EVENTUALLY PUSHES BACK NORTH IN THE FORM OF A WARM FRONT LATE IN THE EXTENDED PERIOD...LOW PRECIP CHANCES WILL REMAIN IN THE FORECAST THROUGH WEDNESDAY NIGHT. TRENDED ON THE WARMER SIDE OF GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD DUE TO SOUTHWESTERLY FLOW. HIGHS WILL TOP OFF IN THE MID TO UPPER 70S WITH LOWS GENERALLY IN THE 50S. && .AVIATION /DISCUSSION FOR THE 301800Z TAFS/... ISSUED AT 1234 PM EDT THU APR 30 2015 THREAT FOR SCATTERED SHOWERS/ISOLATED LIGHTNING STRIKES WILL CONTINUE IN THE VICINITY OF THE TAF SITES THROUGH ABOUT 010000Z AS A VORTICITY LOBE DROPS SOUTH THROUGH THE LOCAL AREA. POTENTIAL FOR ANY DIRECT IMPACTS TOO LOW TO MENTION IN THE FORECAST AT THIS TIME. OTHERWISE...DIURNAL CLOUD BASES AROUND 040 WITH LAYERED CLOUDS ABOVE EXPECTED TO THIN OUT TOWARDS/AFTER SUNSET WITH LOSS OF HEATING AND PASSAGE OF VORTICITY LOBE. OCCASIONAL SURFACE WIND GUSTS AROUND 20 KTS FROM 340-010 DEGREES THIS AFTERNOON SHOULD DIMINISH WITH SUNSET. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....TDUD AVIATION...JAS VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1025 AM EDT THU APR 30 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 225 AM EDT THU APR 30 2015 AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WISCONSIN WILL PUSH ACROSS INDIANA TODAY. THIS WILL RESULT IN SOME CLOUDS ALONG WITH CHANCES FOR A FEW RAIN SHOWERS AND ISOLATED THUNDERSTORMS. THE UPPER LOW WILL DEPART TONIGHT...ALLOWING HIGH PRESSURE TO BUILD ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS WILL BRING DRY AND PLEASANT WEATHER TO CENTRAL INDIANA FOR THE START OF WEEKEND. CHANCE FOR RAIN WILL RETURN TO CENTRAL INDIANA BY SUNDAY AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY APPROACHES THE AREA ALONG WITH WARMER AND MORE HUMID AIR. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1006 AM EDT THU APR 30 2015 CENTER OF THE UPPER LEVEL LOW CURRENTLY LOCATED OVER SOUTHWEST LOWER MICHIGAN WITH FORCING ALOFT EXTENDING SOUTH INTO THE REGION. SEEING A MIX OF CLOUDS WITH POCKETS OF LIGHT SHOWERS AS WELL. TEMPS AS OF 14Z GENERALLY RANGED FROM THE UPPER 40S TO MID 50S. THE UPPER LOW WILL TRACK SOUTHEAST ACROSS THE AREA THROUGH THE AFTERNOON...MAINTAINING UNSETTLED WEATHER WITH SCATTERED CLOUDS AND PRECIP. RAP DATA SHOWING VERY COLD AIR ALOFT ASSOCIATED WITH THIS SYSTEM...ON THE ORDER OF -27 TO -29C AT 500MB. PRESENCE OF THE VERY COLD AIR WILL ENABLE CLOUDS TO EXPAND INTO COVERAGE INTO THE AFTERNOON...AS WELL AS PROMOTE SHOWERS AND ISOLATED CONVECTION. AXIS OF 100-300 J/KG CAPE IN THE HAIL GROWTH LAYER SETTING UP OVER SOUTHEAST HALF OF THE FORECAST AREA THIS AFTERNOON. COMBINED WITH IMPRESSIVE LAPSE RATES IN THE LOWER LEVELS...EXPECT A FEW LIGHTNING STRIKES WITHIN SOME OF THE STRONGER CELLS. WILL INTRODUCE ISOLATED THUNDER MAINLY ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY METRO-MUNCIE LINE. GRAUPEL AND OR SMALL HAIL WILL ALSO BE A POSSIBILITY WITH ANY STRONGER CELL AS WET BULB ZERO LEVELS PROGGED AT 3500-4000FT FOR MUCH OF THE AFTERNOON. PRECIP WILL DIMINISH FROM NORTH TO SOUTH LATE THIS AFTERNOON AS THE UPPER LOW TRACKS INTO NORTHERN KENTUCKY AND INSTABILITY IS LOST. BASED ON MODEL SOUNDINGS...BROUGHT IN WIND GUSTS TO 20-25MPH FOR THE AFTERNOON AS WELL. EXPECT HIGHS MAINLY IN THE MID/UPPER 50S...POSSIBLY LOWER 60S OVER FAR SOUTHERN COUNTIES. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... ISSUED AT 225 AM EDT THU APR 30 2015 MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS. GFS AND NAM BOTH AGREE THAT THE UPPER LOW WILL QUICKLY DEPART THIS EVENING...AND ALONG WITH THE LOSS OF DAYTIME HEATING...AND THE MINIMAL CHANCE FOR SHOWERS TO BEGIN WITH WILL DIMINISH TO NIL. GFS AND NAM THEN ALLOW THE STRONG RIDGE THAT IS IN PLACE OVER THE WESTERN PLAINS TO BUILD EAST ACROSS INDIANA AND THE GREAT LAKES. FORECAST SOUNDINGS ALSO DRY OUT AS HIGH PRESSURE BUILDS ACROSS THE AREA THROUGH THIS PERIOD. THUS WILL TREND TOWARD MOSTLY CLEAR NIGHT AND MOSTLY SUNNY DAYS. AS THE UPPER LOW DEPARTS TONIGHT WARM AIR ADVECTION BEGINS TONIGHT AS THE DOME OF COLD AIR ASSOCIATED WITH THE UPPER LOW DEPARTS. GIVEN THIS WILL TREND TONIGHTS LOWS TOWARD THE WARMER MAVMOS. SUBTLE WARM AIR ADVECTION PATTERN CONTINUES ON FRIDAY INTO SATURDAY AS 850MB TEMPS REACH NEAR 7C BY SAT. WILL TREND HIGHS WITH A SLOWLY GRADUAL WARMING TREND. A MAVMOS/METMOS BLEND SHOULD WORK FINE THERE. && .LONG TERM /SUNDAY THROUGH WEDNESDAY NIGHT/... ISSUED AT 318 AM EDT THU APR 30 2015 A WARMER AND SLIGHTLY MORE HUMID AIRMASS WILL BE IN PLACE FOR THE LONG TERM PERIOD AS A WARM FRONT ENTERS THE LOWER MIDWEST. HOWEVER...WITHOUT ANY SIGNIFICANT LIFTING MECHANISMS AND RIDGING ALOFT...SHOWER AND THUNDERSTORM CHANCES WILL BE LOW. MOST CONVECTIVE ACTIVITY WILL BE DIURNALLY DRIVEN. CHANCES WILL INCREASE SLIGHTLY ON TUESDAY NIGHT THOUGH AS A COLD FRONT MOVES ACROSS CENTRAL INDIANA. AS THIS FRONT STALLS OUT AND EVENTUALLY PUSHES BACK NORTH IN THE FORM OF A WARM FRONT LATE IN THE EXTENDED PERIOD...LOW PRECIP CHANCES WILL REMAIN IN THE FORECAST THROUGH WEDNESDAY NIGHT. TRENDED ON THE WARMER SIDE OF GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD DUE TO SOUTHWESTERLY FLOW. HIGHS WILL TOP OFF IN THE MID TO UPPER 70S WITH LOWS GENERALLY IN THE 50S. && .AVIATION /DISCUSSION FOR THE 301500Z KIND TAF UPDATE/... ISSUED AT 1025 AM EDT THU APR 30 2015 VORTICITY LOBE CURRENTLY DROPPING SOUTH ACROSS SOUTHERN LAKE MICHIGAN INTO NORTHERN ILLINOIS IS EXPECTED TO MOVE INTO THE LOCAL AREA BY THE EARLY TO MID AFTERNOON HOURS. SCATTERED SHOWER ACTIVITY IS POSSIBLE WITH THIS FEATURE...HOWEVER THE CHANCES FOR A DIRECT IMPACT ARE TOO LOW TO MENTION AT THIS TIME. CONVECTIVE PARAMETERS INDICATE SOME POTENTIAL FOR A FEW LIGHTNING STRIKES AS WELL. SURFACE WIND REALLY DON/T PICK UP MUCH UNTIL THE UPPER AIR FEATURE GETS CLOSER...SO WILL PUSH BACK THE TIMING OF THE WIND GUSTS A COUPLE MORE HOURS. PREVIOUS DISCUSSION FOLLOWS. VFR CONDITIONS WILL PREVAIL FOR DURATION OF TAF PERIOD DESPITE SOME LOW RAIN CHANCES /MAINLY AT KHUF AND KBMG/ DUE TO AN UPPER LEVEL LOW. WINDS WILL BE NORTHWESTERLY...INCREASING TO 12 TO 14 KTS WITH GUSTS TO 21 KTS LATER THIS MORNING. WINDS WILL TAPER OFF THIS EVENING BUT REMAIN NORTHERLY. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....TDUD AVIATION...TDUD/JAS VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1006 AM EDT THU APR 30 2015 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 225 AM EDT THU APR 30 2015 AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WISCONSIN WILL PUSH ACROSS INDIANA TODAY. THIS WILL RESULT IN SOME CLOUDS ALONG WITH CHANCES FOR A FEW RAIN SHOWERS AND ISOLATED THUNDERSTORMS. THE UPPER LOW WILL DEPART TONIGHT...ALLOWING HIGH PRESSURE TO BUILD ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS WILL BRING DRY AND PLEASANT WEATHER TO CENTRAL INDIANA FOR THE START OF WEEKEND. CHANCE FOR RAIN WILL RETURN TO CENTRAL INDIANA BY SUNDAY AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY APPROACHES THE AREA ALONG WITH WARMER AND MORE HUMID AIR. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1006 AM EDT THU APR 30 2015 CENTER OF THE UPPER LEVEL LOW CURRENTLY LOCATED OVER SOUTHWEST LOWER MICHIGAN WITH FORCING ALOFT EXTENDING SOUTH INTO THE REGION. SEEING A MIX OF CLOUDS WITH POCKETS OF LIGHT SHOWERS AS WELL. TEMPS AS OF 14Z GENERALLY RANGED FROM THE UPPER 40S TO MID 50S. THE UPPER LOW WILL TRACK SOUTHEAST ACROSS THE AREA THROUGH THE AFTERNOON...MAINTAINING UNSETTLED WEATHER WITH SCATTERED CLOUDS AND PRECIP. RAP DATA SHOWING VERY COLD AIR ALOFT ASSOCIATED WITH THIS SYSTEM...ON THE ORDER OF -27 TO -29C AT 500MB. PRESENCE OF THE VERY COLD AIR WILL ENABLE CLOUDS TO EXPAND INTO COVERAGE INTO THE AFTERNOON...AS WELL AS PROMOTE SHOWERS AND ISOLATED CONVECTION. AXIS OF 100-300 J/KG CAPE IN THE HAIL GROWTH LAYER SETTING UP OVER SOUTHEAST HALF OF THE FORECAST AREA THIS AFTERNOON. COMBINED WITH IMPRESSIVE LAPSE RATES IN THE LOWER LEVELS...EXPECT A FEW LIGHTNING STRIKES WITHIN SOME OF THE STRONGER CELLS. WILL INTRODUCE ISOLATED THUNDER MAINLY ALONG AND SOUTHEAST OF A TERRE HAUTE-INDY METRO-MUNCIE LINE. GRAUPEL AND OR SMALL HAIL WILL ALSO BE A POSSIBILITY WITH ANY STRONGER CELL AS WET BULB ZERO LEVELS PROGGED AT 3500-4000FT FOR MUCH OF THE AFTERNOON. PRECIP WILL DIMINISH FROM NORTH TO SOUTH LATE THIS AFTERNOON AS THE UPPER LOW TRACKS INTO NORTHERN KENTUCKY AND INSTABILITY IS LOST. BASED ON MODEL SOUNDINGS...BROUGHT IN WIND GUSTS TO 20-25MPH FOR THE AFTERNOON AS WELL. EXPECT HIGHS MAINLY IN THE MID/UPPER 50S...POSSIBLY LOWER 60S OVER FAR SOUTHERN COUNTIES. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... ISSUED AT 225 AM EDT THU APR 30 2015 MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS. GFS AND NAM BOTH AGREE THAT THE UPPER LOW WILL QUICKLY DEPART THIS EVENING...AND ALONG WITH THE LOSS OF DAYTIME HEATING...AND THE MINIMAL CHANCE FOR SHOWERS TO BEGIN WITH WILL DIMINISH TO NIL. GFS AND NAM THEN ALLOW THE STRONG RIDGE THAT IS IN PLACE OVER THE WESTERN PLAINS TO BUILD EAST ACROSS INDIANA AND THE GREAT LAKES. FORECAST SOUNDINGS ALSO DRY OUT AS HIGH PRESSURE BUILDS ACROSS THE AREA THROUGH THIS PERIOD. THUS WILL TREND TOWARD MOSTLY CLEAR NIGHT AND MOSTLY SUNNY DAYS. AS THE UPPER LOW DEPARTS TONIGHT WARM AIR ADVECTION BEGINS TONIGHT AS THE DOME OF COLD AIR ASSOCIATED WITH THE UPPER LOW DEPARTS. GIVEN THIS WILL TREND TONIGHTS LOWS TOWARD THE WARMER MAVMOS. SUBTLE WARM AIR ADVECTION PATTERN CONTINUES ON FRIDAY INTO SATURDAY AS 850MB TEMPS REACH NEAR 7C BY SAT. WILL TREND HIGHS WITH A SLOWLY GRADUAL WARMING TREND. A MAVMOS/METMOS BLEND SHOULD WORK FINE THERE. && .LONG TERM /SUNDAY THROUGH WEDNESDAY NIGHT/... ISSUED AT 318 AM EDT THU APR 30 2015 A WARMER AND SLIGHTLY MORE HUMID AIRMASS WILL BE IN PLACE FOR THE LONG TERM PERIOD AS A WARM FRONT ENTERS THE LOWER MIDWEST. HOWEVER...WITHOUT ANY SIGNIFICANT LIFTING MECHANISMS AND RIDGING ALOFT...SHOWER AND THUNDERSTORM CHANCES WILL BE LOW. MOST CONVECTIVE ACTIVITY WILL BE DIURNALLY DRIVEN. CHANCES WILL INCREASE SLIGHTLY ON TUESDAY NIGHT THOUGH AS A COLD FRONT MOVES ACROSS CENTRAL INDIANA. AS THIS FRONT STALLS OUT AND EVENTUALLY PUSHES BACK NORTH IN THE FORM OF A WARM FRONT LATE IN THE EXTENDED PERIOD...LOW PRECIP CHANCES WILL REMAIN IN THE FORECAST THROUGH WEDNESDAY NIGHT. TRENDED ON THE WARMER SIDE OF GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD DUE TO SOUTHWESTERLY FLOW. HIGHS WILL TOP OFF IN THE MID TO UPPER 70S WITH LOWS GENERALLY IN THE 50S. && .AVIATION /DISCUSSION FOR THE 30/1200Z TAF ISSUANCE/... ISSUED AT 727 AM EDT THU APR 30 2015 VFR CONDITIONS WILL PREVAIL FOR DURATION OF TAF PERIOD DESPITE SOME LOW RAIN CHANCES /MAINLY AT KHUF AND KBMG/ DUE TO AN UPPER LEVEL LOW. WINDS WILL BE NORTHWESTERLY...INCREASING TO 12 TO 14 KTS WITH GUSTS TO 21 KTS LATER THIS MORNING. WINDS WILL TAPER OFF THIS EVENING BUT REMAIN NORTHERLY. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....TDUD AVIATION...TDUD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
639 PM CDT FRI MAY 1 2015 .SYNOPSIS... ISSUED AT 321 PM CDT FRI MAY 1 2015 WEAK FRONTAL BOUNDARY WILL DISSIPATE OVER IOWA TONIGHT AS A FRONTAL BOUNDARY DEVELOPS TO THE NORTHWEST ON SATURDAY. THIS FRONT WILL MOVE SOUTHEAST THROUGH THE AREA SUNDAY AFTERNOON AND NIGHT BEFORE STALLING. THE OVERALL WEATHER PATTERN WILL BE ACTIVE WITH THE FRONT IN THE VICINITY THROUGH THE NEXT WEEK. && .SHORT TERM /TONIGHT/... ISSUED AT 321 PM CDT FRI MAY 1 2015 MAIN FORECAST CONCERN WILL BE PRECIPITATION CHANCES THIS EVENING AND AGAIN VERY LATE IN THE PERIOD. ONGOING PRECIPITATION ACROSS CENTRAL PORTION OF THE CWA WILL PERSIST THROUGH THE EVENING...CONTINUING TO PUSH SLOWLY SOUTHEAST. WEAK BOUNDARY AND FORCING WITH PRECIPITATION WILL CONTINUE TO WEAKEN AND WILL SEE PRECIPITATION CONTINUE TO BECOME MORE SCATTERED THROUGH THE LATE EVENING. HRRR MODEL HAS A GOOD HANDLE ON PRECIPITATION TRENDS...AND HAVE TRENDED THIS WAY FOR POPS. GIVEN CURRENT LACK OF INSTABILITY HAVE LEFT THUNDER MENTION OUT...THOUGH COULD SEE SOME ISOLATED THUNDER IN THE LATE AFTERNOON OR EARLY EVENING WITH INCREASING INSTABILITY IN THE FAR WEST. SHORTWAVE LIFTING NORTH FROM KS/NE WILL BEGIN TO PUSH INTO SOUTHWEST NEAR 12Z. HAVE CUT BACK ON POPS WITH SLIGHTLY SLOWER PROGRESSION OF WAVE AND MOISTURE NOTED...NOT PUSHING INTO CWA UNTIL AFTER 12Z. HOWEVER...PLACEMENT MAY BE TOO FAR SOUTH ACROSS THE WEST. HAVE KEPT OVERNIGHT LOW TEMPERATURES DOWN A DEGREE OR TWO GIVEN HOW PRECIPITATION LIMITED DAYTIME HIGHS...AND EXPECT CLEARING SKIES ACROSS THE NORTH TONIGHT. .LONG TERM /SATURDAY THROUGH FRIDAY/... ISSUED AT 321 PM CDT FRI MAY 1 2015 CONTINUED WAA AND POCKETS OF STRONGER THETA-E WILL DOMINATE THROUGH THE NEXT WEEK. A WEAK FEATURE WILL MOVE THROUGH THE AREA ON SATURDAY BRINGING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS...BUT NOTHING TO REALLY FOCUS ON WITH THIS. SUNDAY LOOKS TO BE MORE ACTIVE AS DEW POINTS COME UP AND A STRONGER FRONT MOVES IN. CAPE RISES TO AROUND 2000 J/KG OR SO BY MID DAY SUNDAY WITH LITTLE RESIDUAL CAP. OTHER PARAMETERS ARE NOT AS FAVORABLE WITH INFLOW RELATIVELY WEAK AND OVERALL CONVERGENCE ALONG THE FRONT NOT OPTIMAL. STILL, THUNDER CHANCES ARE DECENT AND IT APPEARS THAT MARGINAL TO SLIGHT THREAD FOR SEVERE LOOKS REASONABLE. THE REST OF THE WEEK WILL BE WARMER THAN NORMAL AND WET. TROUGH IN THE WEST WILL SEND OUT PERIODIC PIECES WITH THE NEXT STRONGER PIECE ARRIVING ABOUT THURSDAY...THE NEXT BEYOND THE FORECAST PERIOD. THOUGH THE SEVERE THREAT LOOKS RELATIVELY LOW...THE CHANCES FOR WIDESPREAD RAINFALL IN EXCESS OF 2 INCHES IN A WEEK IS PRETTY GOOD. DO NOT EXPECT THE RAINFALL TO BE A PROBLEM...BUT IT WILL PUT A CRIMP IN PLANTING PROGRESS. && .AVIATION...02/00Z ISSUED AT 639 PM CDT FRI MAY 1 2015 A WEAK FRONTAL BOUNDARY WILL SLOWLY DISSIPATE ACROSS SOUTHERN TAF LOCATIONS AND WEAK FORCING ASSOCIATED WITH THE BOUNDARY WILL ALSO LINGER SO WHILE ONLY LIGHT SHOWERS ARE EXPECTED THEY WILL LINGER THROUGH 06Z...MAINLY AFFECTING KDSM THROUGH 02Z AND KOTM. ABUNDANT MID LEVEL MOISTURE SHOULD KEEP VFR CIGS IN PLACE FOR MOST LOCATIONS EXCEPT FOR KFOD AND KMCW. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MS MAY 15 SHORT TERM...AWB LONG TERM...MS MAY 15 AVIATION...FAB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
540 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 540 PM MDT FRI MAY 1 2015 UPDATE TO GOING FORECAST TO ACCOUNT FOR VEIL OF MID/HIGH CLOUDS CURRENTLY OVER THE AREA. ALL ACTIVITY EMANATING FROM CONVECTION OFF OVER CENTRAL COLORADO. TREND IS TO CONTINUE EASTWARD THRU THE EVENING HOURS BEFORE DECREASING AFTER MIDNIGHT. HAVE GONE WITH CLOUDY BECOMING PARTLY CLOUDY LATE FOR THE CWA. REST OF FORECAST IS ON TRACK AT THIS TIME. CONVECTION OVER CENTRAL COLORADO IS FINALLY EDGING INTO PORTIONS OF EASTERN COLORADO...SO WILL LEAVE CURRENT POPS FOR TRW/RW IN PLACE. && .SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY) ISSUED AT 150 PM MDT FRI MAY 1 2015 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE IN PLACE ACROSS THE SOUTHERN PLAINS WITH WESTERLY FLOW EXTENDING FROM THE GREAT BASIN ACROSS THE CENTRAL ROCKIES AND INTO THE CENTRAL PLAINS. A WEAK SHORTWAVE H5/H7 TROUGH IS IN THE PROCESS OF ROTATING THROUGH THE MEAN FLOW ACROSS THE CENTRAL ROCKIES WITH SHOWER/THUNDERSTORM DEVELOPMENT APPARENT ON UPSTREAM RADARS MOVING EAST OFF THE HIGHER TERRAIN. AT THE SURFACE LOW PRESSURE IS IN PLACE ACROSS THE CWA WITH A STATIONARY FRONT ALONG THE SOUTHEASTERN CORNER OF THE CWA EXTENDING SOUTH IN SOUTHEAST COLORADO. THIS AFTERNOON-TONIGHT...FOCUS CONTINUES TO BE ON POTENTIAL FOR THUNDERSTORMS DEVELOPING OVER THE CWA OR SPREADING EAST INTO THE CWA AS SHORTWAVE MOVES THROUGH THE REGION. WITH FRONT IN PLACE AND AIR MASS DESTABILIZING THERE IS SOME CONCERN THAT ISOLATED THUNDERSTORMS COULD DEVELOP AHEAD OF MAIN SHORTWAVE. HIGH CINH VALUES CURRENTLY IN PLACE ARE INHIBITING CONVECTION CURRENTLY OVER THE CWA DESPITE INCREASING INSTABILITY. AS SHORTWAVE MOVES EAST IT APPEARS THE CAP SHOULD WEAKEN ALLOWING FOR INCREASING CHANCES FROM THE WEST TO THE EAST. BEST PRECIP SIGNAL FROM RAP/HRRR CONTINUES TO BE IN THE SOUTHWEST PART OF THE CWA. 12Z GUIDANCE WAS RUNNING HIGH REGARDING CAPE VALUES MOST OF THE DAY...THOUGH AS SKIES HAVE CLEARED THE LATEST RAP ANALYSIS DOES SHOW 500-1000 KG/J ML CAPE DEVELOPING OVER THE REGION. SHEER IS NOT PARTICULARLY IMPRESSIVE AND AT THIS POINT SEVERE THREAT SEEMS TO BE LIMITED. ANY SHOWER/THUNDERSTORM ACTIVITY SHOULD QUICKLY DISSIPATE OR TRANSITION EAST OF THE CWA THROUGH LATE THIS EVENING AS A SHARP AREA OF SUBSIDENCE MOVES IN BEHIND EXITING SHORTWAVE. SATURDAY...VERY GOOD WAA IS ADVERTISED AND WITH CLEARING SKIES DURING THE FIRST PART OF THE DAY HIGHS SHOULD REACH THE 80S ACROSS THE CWA...POSSIBLY IN THE MID/UPPER 80S IN THE EAST. THE NEXT SHORTWAVE IS SHOWN TO APPROACH THE REGION FROM THE CENTRAL ROCKIES LATE AFTERNOON WITH THUNDERSTORM INITIATION NEAR SURFACE TROUGH ALONG CO/KS BORDER POSSIBLE AFTER 21Z...OTHERWISE BETTER CHANCES ARRIVE LATER IN THE EVENING. MODELS ARE SHOWING VERY UNSTABLE AIR BUILDING OVER THE REGION WITH NAM ADVERTISING 1500-2500 J/KG OF ML CAPE BY LATE AFTERNOON. SHEER IS A LITTLE BETTER THAN TODAY WITH EFFECTIVE SHEER IN EXCESS OF 35KT. WITH THIS IN MIND ANY THUNDERSTORMS THAT DEVELOP LATE TUESDAY AFTERNOON COULD POTENTIALLY ORGANIZE AND BECOME SEVERE. WITH MINIMAL LOW LEVEL SHEER LARGE HAIL/DAMAGING WIND CONTINUE TO BE MAIN CONCERNS. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 218 PM MDT FRI MAY 1 2015 A FLATTENED RIDGE WILL BE OVER THE SOUTHERN PLAINS THROUGH SUNDAY NIGHT WITH WESTERLY FLOW OVER THE CENTRAL PLAINS. THE SOUTHERN PLAINS RIDGE WILL SHIFT EASTWARD MONDAY WITH SOUTHWEST FLOW OVER THE CENTRAL PLAINS. A SURFACE TROUGH OVER EASTERN COLORADO WILL MIGRATE SLOWLY EAST ACROSS NORTHWEST KANSAS THROUGH SUNDAY NIGHT. SURFACE HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY BEHIND THE EXITING TROUGH. A SHORTWAVE MOVES ACROSS THE FA SATURDAY EVENING WITH SUBSIDENCE INDICATED AFTER 06Z TUESDAY AS THE SHORTWAVE SLIDES SOUTHEAST OUT OF THE AREA. H8-7 LAYER MEAN RH IS NOT IDEAL SO WILL KEEP POPS AT SLIGHT CHANCE. CAPE VALUES UP TO 1000 J/KG ARE EXPECTED WITH AN AREA OF 35 KTS SHEAR OVER NORTHEAST COLORADO. A FEW ISOLATED MARGINALLY SEVERE STORMS ARE POSSIBLE. SUBSIDENCE CONTINUES THROUGH SUNDAY MORNING AND INTO THE AFTERNOON. THE NEXT SHORTWAVE SHOULD IMPACT EASTERN COLORADO BY MID TO LATE AFTERNOON. PLAN TO GO WITH CHANCE POPS OVER WESTERN PORTIONS OF EASTERN COLORADO AND ALSO NEAR THE TROUGH AXIS IN THE SOUTHEASTERN FA. GOOD DYNAMICS AND MOISTURE MOVE ACROSS THE FA SUNDAY NIGHT SO WILL GO WITH HIGHER CHANCE POPS ESPECIALLY IN THE WEST DURING THE EVENING WHERE STORMS SHOULD ALREADY BE IN PROGRESS. HIGH CHANCE POPS WILL CONTINUE AFTER 06Z MONDAY AS THE SHORTWAVE IMPACTS THE ENTIRE AREA. MONDAY DOES NOT APPEAR TO BE AS FAVORABLE FOR PRECIPITATION AS HIGH PRESSURE BUILDING IN FROM THE NORTH PUSHES THE SURFACE BOUNDARY FURTHER SOUTH. FURTHERMORE, THE MAIN SURFACE LOW IS OVER SOUTHERN CALIFORNIA, DYNAMICS ARE MORE UNCERTAIN. CONSEQUENTLY LOWERED POPS SOME BUT STILL KEPT CHANCE POPS OVER THE AREA MONDAY AFTERNOON. MIN TEMPERATURES SHOULD VARY FROM THE UPPER 40S TO THE LOWER 50S SATURDAY AND SUNDAY NIGHTS. MAX TEMPERATURES SHOULD RISE TO THE LOWER TO MID 80S SUNDAY AND THEN COOL TO THE MID 60S TO AROUND 70 MONDAY. IN THE EXTENDED...(TUESDAY THROUGH FRIDAY)...ACTIVE WEATHER IS EXPECTED FOR THIS PART OF THE FORECAST. AN UPPER LEVEL TROUGH OVER THE SW CONUS WILL MOVE NORTHEAST AND PHASE INTO A TROUGH OVER THE PACIFIC NORTHWEST. NUMEROUS SHORTWAVES WILL MOVE THROUGH THE FLOW AND ACROSS THE CENTRAL PLAINS. THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE FA ON A DAILY BASIS THROUGH FRIDAY. MIN TEMPERATURES WILL COOL TO THE UPPER 40S AND LOWER 50S. MAX TEMPERATURES SHOULD RANGE FROM 65 TO 70 TUESDAY WARMING TO THE 70S WEDNESDAY THROUGH FRIDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 540 PM MDT FRI MAY 1 2015 MAINLY VFR CONDITIONS EXPECTED FOR BOTH TAF SITES WITH SCT060-070 SCT-BKN150-250. KGLD MAY SEE MVFR FOG 03Z-06Z. VCSH AFT 18Z SATURDAY FOR BOTH TAF SITES...BUT ONLY KGLD MAY SEE VCSH THRU 06Z TONIGHT. WINDS EXPECTED TO MEANDER FROM SW TO SE 5-10KTS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...DR LONG TERM...FS AVIATION...JN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
628 PM CDT Fri May 1 2015 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Saturday) Issued at 333 PM CDT FRI MAY 1 2015 19Z water vapor shows a ridge of high pressure centered over the AZ/NM boarder and broad cyclonic flow from the Gulf of AK through western Canada. Within this pattern, much of the shortwave activity remains along the Canadian boarder. At the surface, a ridge of high pressure was centered over the MS river valley with a weak trough of low pressure from northwest KS through the eastern Dakotas. For tonight and Saturday, there are two potential sources for forcing convection, and confidence in either one is rather so-so. The first is a possible convectively induced vort max (MCV) coming off the central Rockies this evening. The HRRR and RAP have been the most aggressive in holding precip together off the higher terrain and into the forecast area through Saturday morning. These solutions have also be to aggressive in this afternoon`s precip so I don`t know how much weight to put behind this idea with the GFS and NAM shearing out any MCV. At this point, have taken a wait and see approach for the convection to fully move off the mountains. Additionally the MCV may tend to move just southwest of the forecast area. The second forcing mechanism may end up being the low level jet and isentropic lift. The NAM and GFS seem to favor this, developing precip along the NEB state line and moving it into northern MO Saturday morning. However it appears the low level jet will be veered to the southwest with the stronger wind speeds to the west of the area. Additionally theta-e advection is marginal with the low level jet. The models do prog some isentropic lift over far northeast KS which may explain why they are generating precip. Nevertheless confidence is marginal since the low level jet itself is not very strong and moisture advection with the jet is weak. Have kept some 20 to 30 percent POPs across the northern counties through the morning to account for the possibility. Lows tonight should be a little more mild with readings remaining in the lower and mid 50s. Think skies are likely to remain at least partly cloudy with debris clouds spreading in from the west, helping to keep lows in the 50s. Models show some warm air advection through the day Saturday as low level flow remains southerly. Based on 850 temp progs and some insolation through the afternoon, think highs should warm into the upper 70s and lower 80s. .LONG TERM...(Saturday Night through Friday) Issued at 333 PM CDT FRI MAY 1 2015 Increasing low level southerly flow Saturday night into Sunday brings precipitable water values further above normal to near 1.5 inches. Main forcing mechanism approaches Sunday afternoon as a northern branch wave allows a cold front to settle south into the area, likely from southwest Kansas into east central Nebraska. Could see far western locations impacted late in the afternoon as storms could fire not far to the west-southwest, but chances increase in the next few periods as the front ceases its southerly push, between the northern and southern branches. Just how far the front gets is obviously a challenge and will be key for precip potential. Have tapered southern end of precip chances for Sunday night, with best mean chances Monday into Monday night until southerly flow returns to the northwest, ushering the front back north. At this point Tuesday appears the most likely dry period, with a modest but increasingly powerful upper wave rotating northeast into the Plains Tuesday night into Wednesday night. Expect most locations to see at least some precip in this period with deep south flow keeping available moisture plentiful. Beyond this, model differences increase for a much less confidence forecast, though a modified front could be in play with a still warm and moist airmass to support chance PoPs. As for thunderstorm severity, mid/upper flow is not very strong being between the northern and southern branches. With greater confidence in the late weekend/early next week boundary in the vicinity, there will of course be low level shear potential here with ML CAPE likely around 1500 J/kg. In the latter wetter period, the wave`s orientation keeps winds somewhat unidirectional with height, and instability specifics anything but certain with periodic precip quite likely. Expect highs to be generally near to a few degrees above normal, with main problem being depth/persistence of cloud/precip north of the front Monday to bring possibly cooler temps possible in northern areas. && .AVIATION...(For the 00Z TAFs through 00Z Saturday Evening) Issued at 624 PM CDT FRI MAY 1 2015 VFR conditions expected through a majority of the period. There is a slight chance that an isolated shower or thunderstorm could form or pass near and north of the taf sites tomorrow morning around sunrise. Otherwise occasional gusty winds under 20 kts expected through tomorrow afternoon. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
309 PM EDT Thu Apr 30 2015 .SHORT TERM (Now through Friday Night)... Issued at 305 PM EDT Thu Apr 30 2015 Unseasonably cold mid-level low continues to move southward and was centered over west-central IN at mid-afternoon. The low will propagate over central and eastern KY this evening. As expected, cold mid-level temperatures combined with modest low-level heating have steepened lapse rates and facilitated development of scattered to numerous showers and a few thunderstorms. A few cells have produced pea size hail, brief wind gusts up to 40 mph, and some lightning strikes. Currently, radar data shows better precipitation coverage over east-central KY including the Lexington area, and approaching the eastern half of south-central IN from the north. Latest HRRR model reflectivity forecast captures these areas reasonably well. It maintains the southern IN cells, moving them south-southeast into north-central and east-central KY late this afternoon. Other pop up cells could occur elsewhere as well. Thus, will maintain highest coverage/percentage of precipitation east of Interstate 65, especially over east-central KY. Rainfall intensity and coverage will slowly diminish this evening with loss of daytime heating and as the upper low moves eastward. Overnight, dry weather is expected with some clouds remaining over the east, with fewer clouds over western parts of our forecast area. There could be patchy fog near daybreak over parts of east-central KY. It will be chilly, with lows Friday morning in the upper 30s and lower 40s in many areas. On Friday, the mid-level low will continue pulling eastward away from our area. There could be some residual clouds over the east half of our forecast area, but dry weather is expected. Temperatures will begin a warming trend that will last through the weekend and into next week. Expect highs Friday afternoon in the mid 60s to lower 70s. .LONG TERM (Saturday through Thursday)... Issued at 305 PM EDT Thu Apr 30 2015 Saturday - Saturday Night... NW flow aloft will dominate the pattern, meanwhile surface high pressure will be in place. Models have been consistent now for the past several runs in depicting a shortwave embedded in the flow traversing the area on Saturday. Will continue to keep the forecast dry as this feature looks starved of moisture. Instead, will depict an increase in cloud cover through the afternoon, although still expect partly sunny skies. With plenty of peaks at the sun, will call for temps mostly in the mid 70s. A few spots that see more clouds may stay in the low 70s. Dry conditions will continue into Saturday night where weak and progressive upper ridging slides over the Ohio River Valley. Meanwhile, surface high pressure remains at the surface. Given good radiational cooling conditions, lows will still slide into the upper 40s and low 50s. Sunday - Thursday... Low amplitude NW flow aloft will transition to upper ridging over the CWA to end the weekend and start the new work week. This ridge is then expected to hold over the area through the end of the week. A frontal boundary that looks to stall nearly parallel to the upper flow should stay well to the north across the southern Great Lakes. This pattern will result in continued dry conditions and temperatures rising above normal for this time of year. Can`t rule out an extremely isolated shower or t-storm at some point through the week, however lack of a trigger and mid level subsidence inversion is enough to keep a dry forecast going. Have nudged temperatures up around MEX guidance given the warmer pattern, and wouldn`t be surprised if they end up a couple of degrees warmer. This will result in forecast temperatures more solidly in the low and mid 80s Tue-Thur. Will go with upper 70s to around 80 for Sunday, and around 80 for Monday. Lows each night should mostly be in the 50s, with the usual warm spots likely around 60. && .AVIATION (18Z TAF Update)... Updated at 115 PM EDT Thu Apr 30 2015 Cold mid-level closed low will move south-southeast into southern IN this afternoon and eastern KY this evening. This system combined with low-level heating will result in scattered to numerous showers and embedded thunderstorms this afternoon, before weakening and moving east of the TAF area this evening. Small hail is likely with thunderstorms. Greatest coverage should be east-central KY, including around LEX. Overall, clouds and visibilities should remain VFR, but could dip into MVFR briefly in heavier showers. Overnight and Friday, conditions will be more tranquil with VFR conditions, although there could be patchy MVFR fog at LEX around daybreak. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Short Term........TWF Long Term.........BJS Aviation..........TWF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
135 AM EDT THU APR 30 2015 .UPDATE... ISSUED AT 120 AM EDT THU APR 30 2015 JUST A QUICK UPDATE TO FINE TUNE THE SKY AND POPS THROUGH THE REST OF THE NIGHT...MAINLY TO SLOW THE ARRIVAL OF SHOWERS FROM THE NORTHWEST. HOWEVER...THE LATEST HRRR AND NAM12 DO BRING PCPN INTO THE NORTHERN PORTION OF THE AREA SHORTLY AFTER SUNRISE SO DID NOT BACK OFF TOO DRAMATICALLY. ALSO NUDGED THE HOURLY T/TD GRIDS TOWARD THE LATEST SHORTBLEND GUIDANCE...CURRENT OBS...AND TRENDS. THESE GRID UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1035 PM EDT WED APR 29 2015 CONTINUING TO SEE PATCHES OF CLOUDS ACROSS PORTIONS OF EASTERN KENTUCKY THIS EVENING WITH MORE SUBSTANTIAL CLOUDS ACROSS NORTHERN AND CENTRAL KENTUCKY. THIS AREA OF CLOUD COVER TO OUR NORTH AND WEST WILL SLOWLY ADVECT INTO THE REGION OVERNIGHT. THE THINNING CLOUDS HAVE ALLOWED A FEW OF THE DEEPER VALLEYS TO DECOUPLE AND COOL QUICKER THIS EVENING. THEREFORE MADE UPDATE TO TEMPS...DEWPOINTS...AND CLOUDS THIS UPDATE TO BETTER REPRESENT THE LATEST OBS AND TRENDS. ALSO OPTED TO SLOW RAIN SHOWER CHANCES DOWN SLIGHTLY GOING INTO THE OVERNIGHT AND EARLY MORNING HOURS. OTHERWISE NO MAJOR CHANGES NEEDED FOR THIS UPDATE. UPDATE ISSUED AT 656 PM EDT WED APR 29 2015 CONTINUING TO SEE PATCHES OF CUMULUS ACROSS THE BLUEGRASS STATE THIS AFTERNOON. THIS IS BRINGING PARTLY CLOUDY SKIES AT TIMES TO PORTIONS OF EASTERN KENTUCKY...OTHERWISE DRY CONDITIONS ARE IN PLACE AT THE SURFACE. NO MAJOR CHANGES NEEDED FOR THIS UPDATE WITH MINOR ADJUSTMENTS MADE TO TEMPS...DEWPOINTS...AND SKY FOR THE LATEST OBS AND TRENDS. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 328 PM EDT WED APR 29 2015 A SOUTHERN STREAM LOW IS CURRENTLY PUSHING EWD TOWARD THE ATLANTIC COAST AS A NORTHERN STREAM CLOSED LOW TRACKS SWD FROM THE GREAT LAKES REGION. IN BETWEEN THESE TWO SYSTEMS...A MID LEVEL SHORTWAVE WILL TRACK INTO OUR REGION TONIGHT...BRINGING A MID LEVEL CLOUD DECK THAT WILL LOWER THROUGHOUT THE NIGHT. TOMORROW...THE CLOSED LOW WILL QUICKLY APPROACH EAST KENTUCKY AND THEN MOVE OVER OUR AREA BY TOMORROW AFTERNOON AND EVENING WITH PLENTY OF MID LEVEL ENERGY AND A CORE OF COLDER 500 MB TEMPS. THE SYSTEM WILL THEN EXIT KENTUCKY EARLY FRIDAY MORNING AS SURFACE HIGH PRESSURE BUILDS IN FROM THE WEST/NORTHWEST. AT THE SURFACE...SHOWERS WILL BE POSSIBLE BY DAWN IN THE NORTHWEST PORTION OF THE AREA AS THE SURFACE FEATURE LINKED TO THE CLOSED LOW MOVES INTO KENTUCKY. LAPSE RATES WILL INCREASE THROUGHOUT THURSDAY AFTERNOON WITH INCREASING CAPE AND FALLING LI/S AS THE UPPER LOW MOVES OVERHEAD. AS A RESULT...THUNDERSTORMS WILL BE POSSIBLE IN THE MORNING...AND LIKELY BY THE AFTERNOON DUE TO BETTER INSTABILITY. HAVE UPGRADED THUNDERSTORMS TO LIKELY FROM CHANCES BETWEEN 18-22Z. GRAUPEL IS ALSO A POSSIBILITY FROM ANY STRONGER STORM SO WILL KEEP MENTION OF THIS IN THE HWO. THE CLOUDS AND CONVECTION WILL LIKELY KEEP TEMPS ON THE COOL SIDE THURSDAY. THE CHANCE FOR STORMS WILL COME TO AN END ON THURSDAY EVENING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 350 PM EDT WED APR 29 2015 AN UPPER LEVEL LOW AND TROUGH WILL DEPART TO THE EAST OF THE REGION AT THE START OF THE PERIOD...WITH SHORTWAVE RIDGING MOVING INTO THE OHIO VALLEY IN ITS WAKE. GRADUAL HEIGHT RISES ARE EXPECTED ON AVERAGE FROM THE WEEKEND AND INTO EARLY NEXT WEEK. IN FACT...RECENT MODEL RUNS POINT TOWARD THE RIDGING REMAINING IN CONTROL INTO THE MIDDLE OF NEXT WEEK. ON FRIDAY...ONLY ISOLATED TO SCATTERED SHOWERS ARE ANTICIPATED...AND MAINLY IN THE MORNING TO MIDDAY AS THE UPPER LEVEL SYSTEM DEPARTS. ONCE THE UPPER SYSTEM DEPARTS TO START THE WEEKEND...WARMER AND MAINLY DRY WEATHER IS ANTICIPATED. EVEN A COUPLE OF DISTURBANCES WILL DROP INTO THE REGION IN THE NW FLOW ALOFT TO START THE WEEKEND...AND SOME OF THE GFS AND ECMWF RUNS GENERATE SOME PRECIPITATION ON SATURDAY OR SUNDAY. HOWEVER...ATTM WE DO NOT EXPECT ANYTHING MORE THAN SOME MAINLY MID LEVEL CLOUDS FROM TIME TO TIME OVER THE WEEKEND. THE RIDGING SHOULD KEEP A FRONTAL ZONE NORTH OF THE OH RIVER NEAR THE GREAT LAKES REGION WITH ASSOCIATED MCS ACTIVITY LIKELY REMAINING WELL NORTH OF THE AREA...FROM EARLY IN THE WEEK UNTIL AT LEAST MIDWEEK. TEMPERATURES IN THE WARM SPOTS MAY NEAR THE 80 DEGREE MARK DURING THAT TIME. DIFFERENTIAL HEATING NEAR THE VA BORDER MIGHT BE THE ONLY OTHER REAL TRIGGER FOR ANY ISOLATED CONVECTION PRIOR TO AT LEAST MIDWEEK...BUT THAT IS DOUBTFUL AND HAVE ONLY WENT WITH ISOLATED POPS IN THAT AREA. EVEN FOR WEDNESDAY...WE HAVE ONLY USED SLIGHT CHANCE POPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 135 AM EDT THU APR 30 2015 VFR CONDITIONS WILL CONTINUE TO BE THE STORY FOR MUCH OF THE NIGHT AND THROUGH MIDDAY THURSDAY. CLOUDS WILL BE ON THE INCREASE THROUGH THE REST OF THE NIGHT AS A SURFACE COLD FRONT AND UPPER LEVEL CLOSED LOW DROP SOUTH OUT OF THE GREAT LAKES INTO KY DURING THE DAY THURSDAY. THIS SYSTEM WILL BRING A THREAT OF RAIN SHOWERS TO THE SYM TAF SITE TOWARD DAYBREAK FOLLOWED BY SHOWERS AND THE POTENTIAL FOR THUNDERSTORMS SPREADING SOUTH AS WE MOVE THROUGH THE DAY ON THURSDAY...UNDER THE AUSPICES OF INCREASING INSTABILITY. THE STRONGEST SHOWER OR STORM COULD HAVE MVFR CIGS AND VIS FOR A BRIEF TIME...BUT THE PREVAILING CONDITIONS WILL BE VFR...SO JUST WENT WITH A TEMPO FOR THESE TIMES. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE INTO THE FIRST PART OF THE EVENING BEFORE THE INSTABILITY WANES. AS THE SFC WAVE PASSES TO THE EAST LOOK FOR CIGS TO FALL TO MVFR OR LOWER LATER THURSDAY EVENING AND CONTINUING LOW THROUGH THE NIGHT. WINDS...OUTSIDE OF ANY THUNDERSTORM...WILL BE AROUND 10 KTS OR LESS...GENERALLY FROM THE NORTHWEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JVM/GREIF LONG TERM...JP AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
620 PM EDT THU APR 30 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 329 PM EDT THU APR 30 2015 HIGH PRESSURE WILL BRING FAIR WEATHER THE REMAINDER OF THE WEEK AND INTO MUCH OF THE WEEKEND. TEMPERATURES WILL GRADUALLY MODERATE EACH DAY...REACHING THE UPPER 60S ON FRIDAY AND THE LOWER 70S ON SATURDAY AND SUNDAY. THE PATTERN LOOKS TO TURN WET LATE IN THE WEEKEND AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY WILL BE DRAPED ACROSS THE REGION. SHOWERS AND STORMS ARE IN THE FORECAST FROM SUNDAY AFTERNOON THROUGH WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 329 PM EDT THU APR 30 2015 VERY LITTLE IN THE WAY OF SHORT TERM FORECAST ISSUES WITH HIGH PRESSURE IN CONTROL OF THE WEATHER. THERE MAY BE A STRAY SHOWER THIS EVENING TOWARD BATTLE CREEK AND JACKSON...BUT OTHERWISE EXPECTING DRY WEATHER FROM TONIGHT THROUGH SATURDAY NIGHT. TEMPERATURES WILL BE SLIGHTLY ABOVE SEASONAL NORMS FOR THIS TIME OF YEAR WHICH WILL BE A CHANGE FROM WHERE WE HAVE BEEN OF LATE. OVERALL SKIES WILL BE MOSTLY CLEAR TO PARTLY CLOUDY THROUGH THE PERIOD. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 329 PM EDT THU APR 30 2015 ITS CONTINUING TO LOOK RATHER ACTIVE THROUGH THE LONG TERM PERIOD WITH SHOWERS AND THUNDERSTORMS BEING THE MAIN FOCUS. THE INITIAL ONSET OF PRECIPITATION IS LOOKING TO HOLD OFF RATHER LATE IN THE WEEKEND. AS HAS BEEN THE CASE FOR THE LAST FEW DAYS...THE GFS AND ECMWF HAVE THEIR DISAGREEMENTS WITH TIMING AND PLACEMENT OF THE FRONTAL BOUNDARY THAT WILL ULTIMATELY BE RESPONSIBLE FOR WET CONDITIONS. THE ECMWF IS QUITE PERSISTENT ON PUSHING AN AREA OF LOW PRESSURE EAST OF THE HUDSON BAY. A WEAKER DISTURBANCE DEVELOPS AND ROTATES AROUND THE MAIN LOW AND ATTEMPTS TO PUSH COOLER AIR SOUTHWARD. THE GFS IS SLOWER AND FURTHER WEST WITH THIS MAIN LOW AND KEEPS THE BOUNDARY FURTHER NORTH. THIS WOULD PLAY A LARGE ROLE IN NOT ONLY PRECIPITATION AMOUNTS THROUGH THE AREA BUT ALSO THE TEMPERATURE SPREAD FROM NORTH TO SOUTH. THE PERSISTENCE OF THE ECMWF WOULD NORMALLY BE COMFORTING...BUT RECENT EVENTS HAVE ACTUALLY BEEN WON OUT BY THE GFS. THEREFORE...THE CONFIDENCE ON THE FRONTAL BOUNDARY PLACEMENT IS STILL RATHER LOW. WHILE THE ECMWF IS LESS AMPLIFIED WITH THE UPPER LEVEL RIDGE...THE GFS HAS A TROUGH OVER THE WEST...WHICH WOULD EXPLAIN THE REASONING FOR THE NORTHWARD EXTEND OF THE FRONTAL BOUNDARY AND MORE AMPLIFIED PATTERN. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 620 PM EDT THU APR 30 2015 THE CLOUDS ASSOCIATED WITH THE UPPER LOW ARE DEPARTING AS I WRITE THIS DISCUSSION. I WOULD EXPECT THE TAF SITES OF MKG...GRR AND AZO (CLOSER TO LAKE MICHIGAN) WILL BE CLEAR BY 01Z-02Z BUT THE MORE EASTERN TAF SITES IT MAY TAKE UNTIL 06Z FOR ALL OF THE MID CLOUDS TO DEPART AS UPPER LOW SLOWLY SINKS SOUTH AND SOUTHEAST OF THE AREA. ONCE THAT HAPPENS THROUGH SKIES SHOULD BE TOTALLY CLEAR THROUGH FRIDAY NIGHT. && .MARINE... ISSUED AT 329 PM EDT THU APR 30 2015 MAINTAINED THE SMALL CRAFT ADVISORY WITH THIS FORECAST PACKAGE...BUT IT LOOKS LIKE IT IS SOMEWHAT MARGINAL UP NORTH TOWARDS BIG AND LITTLE SABLE POINTS. THAT SAID...BIG SABLE OB IS SHOWING GUSTS OF 21-24 KNOTS THE LAST FEW HOURS. THE HRRR CONTINUES TO SHOW A CORE OF WIND WORKING DOWN THE SHORE THIS AFTERNOON AND EVENING WITH GUSTS TO AROUND 25 KNOTS. WAVES SHOULD COME UP INTO THE 3-5 FOOT RANGE FOR A FEW HOURS AS THE WIND SHIFTS SOUTH. EXPECTING PORT SHELDON TO COME UP OVER THE NEXT 1-3 HOURS. WINDS AND WAVES SHOULD BE FAIRLY TAME AFTER THIS EVENING AS HIGH PRESSURE BUILDS IN THE NEXT COUPLE DAYS. && .HYDROLOGY... ISSUED AT 139 PM EDT THU APR 30 2015 RIVERS ARE RUNNING NEAR TO BELOW NORMAL. NO ISSUES ARE EXPECTED THROUGH THE WEEKEND. WE ARE MONITORING THE POTENTIAL FOR OVER AN INCH OF RAINFALL DURING THE FIRST HALF OF NEXT WEEK. CONFIDENCE IS CURRENTLY NOT HIGH ON WHERE THE AXIS OF HEAVIEST RAIN WILL BE. WITH THE GREEN-UP UNDERWAY... PLANTS AND SOIL ARE ABLE TO ABSORB A GREATER AMOUNT OF RAIN THAN EARLIER IN THE SPRING. THIS WILL BUFFER RIVER RESPONSE TO SOME EXTENT. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR LMZ847>849. SMALL CRAFT ADVISORY UNTIL 3 AM EDT FRIDAY FOR LMZ844>846. && $$ SYNOPSIS...DUKE SHORT TERM...DUKE LONG TERM...JAM AVIATION...WDM HYDROLOGY...CAS MARINE...DUKE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
329 PM EDT THU APR 30 2015 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/MARINE .SYNOPSIS... ISSUED AT 329 PM EDT THU APR 30 2015 HIGH PRESSURE WILL BRING FAIR WEATHER THE REMAINDER OF THE WEEK AND INTO MUCH OF THE WEEKEND. TEMPERATURES WILL GRADUALLY MODERATE EACH DAY...REACHING THE UPPER 60S ON FRIDAY AND THE LOWER 70S ON SATURDAY AND SUNDAY. THE PATTERN LOOKS TO TURN WET LATE IN THE WEEKEND AND EARLY NEXT WEEK AS A FRONTAL BOUNDARY WILL BE DRAPED ACROSS THE REGION. SHOWERS AND STORMS ARE IN THE FORECAST FROM SUNDAY AFTERNOON THROUGH WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 329 PM EDT THU APR 30 2015 VERY LITTLE IN THE WAY OF SHORT TERM FORECAST ISSUES WITH HIGH PRESSURE IN CONTROL OF THE WEATHER. THERE MAY BE A STRAY SHOWER THIS EVENING TOWARD BATTLE CREEK AND JACKSON...BUT OTHERWISE EXPECTING DRY WEATHER FROM TONIGHT THROUGH SATURDAY NIGHT. TEMPERATURES WILL BE SLIGHTLY ABOVE SEASONAL NORMS FOR THIS TIME OF YEAR WHICH WILL BE A CHANGE FROM WHERE WE HAVE BEEN OF LATE. OVERALL SKIES WILL BE MOSTLY CLEAR TO PARTLY CLOUDY THROUGH THE PERIOD. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 329 PM EDT THU APR 30 2015 ITS CONTINUING TO LOOK RATHER ACTIVE THROUGH THE LONG TERM PERIOD WITH SHOWERS AND THUNDERSTORMS BEING THE MAIN FOCUS. THE INITIAL ONSET OF PRECIPITATION IS LOOKING TO HOLD OFF RATHER LATE IN THE WEEKEND. AS HAS BEEN THE CASE FOR THE LAST FEW DAYS...THE GFS AND ECMWF HAVE THEIR DISAGREEMENTS WITH TIMING AND PLACEMENT OF THE FRONTAL BOUNDARY THAT WILL ULTIMATELY BE RESPONSIBLE FOR WET CONDITIONS. THE ECMWF IS QUITE PERSISTENT ON PUSHING AN AREA OF LOW PRESSURE EAST OF THE HUDSON BAY. A WEAKER DISTURBANCE DEVELOPS AND ROTATES AROUND THE MAIN LOW AND ATTEMPTS TO PUSH COOLER AIR SOUTHWARD. THE GFS IS SLOWER AND FURTHER WEST WITH THIS MAIN LOW AND KEEPS THE BOUNDARY FURTHER NORTH. THIS WOULD PLAY A LARGE ROLE IN NOT ONLY PRECIPITATION AMOUNTS THROUGH THE AREA BUT ALSO THE TEMPERATURE SPREAD FROM NORTH TO SOUTH. THE PERSISTENCE OF THE ECMWF WOULD NORMALLY BE COMFORTING...BUT RECENT EVENTS HAVE ACTUALLY BEEN WON OUT BY THE GFS. THEREFORE...THE CONFIDENCE ON THE FRONTAL BOUNDARY PLACEMENT IS STILL RATHER LOW. WHILE THE ECMWF IS LESS AMPLIFIED WITH THE UPPER LEVEL RIDGE...THE GFS HAS A TROUGH OVER THE WEST...WHICH WOULD EXPLAIN THE REASONING FOR THE NORTHWARD EXTEND OF THE FRONTAL BOUNDARY AND MORE AMPLIFIED PATTERN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 139 PM EDT THU APR 30 2015 THE PATTERN HAS SHIFTED IN MORE OF AN OPTIMISTIC DIRECTION. VFR CONDITIONS ARE EXPECTED THROUGH A LARGE PORTION OF THE AREA. THERE IS SOME QUESTION TO THE EXTENT AND DURATION OF CLOUD COVER AT OUR SOUTHEASTERN SITES. A BROKEN DECK IS EXPECTED TO ROTATE THROUGH THESE LOCATIONS THROUGH EARLY EVENING...BUT THE MOISTURE FOR THIS DECK IS THIN AND EVACUATES RATHER QUICKLY THROUGH LATE EVENING. WINDS WERE ANOTHER AREA I TRENDED DOWN ON AS IT SEEMS WE ARE UNDER-PERFORMING FROM PREVIOUS THOUGHTS. BY LATE EVENING CONDITIONS SHOULD CONTINUE TO IMPROVE AS WINDS DIE DOWN AND ANY CLOUD COVER AROUND KLAN AND KJXN ERODES. && .MARINE... ISSUED AT 329 PM EDT THU APR 30 2015 MAINTAINED THE SMALL CRAFT ADVISORY WITH THIS FORECAST PACKAGE...BUT IT LOOKS LIKE IT IS SOMEWHAT MARGINAL UP NORTH TOWARDS BIG AND LITTLE SABLE POINTS. THAT SAID...BIG SABLE OB IS SHOWING GUSTS OF 21-24 KNOTS THE LAST FEW HOURS. THE HRRR CONTINUES TO SHOW A CORE OF WIND WORKING DOWN THE SHORE THIS AFTERNOON AND EVENING WITH GUSTS TO AROUND 25 KNOTS. WAVES SHOULD COME UP INTO THE 3-5 FOOT RANGE FOR A FEW HOURS AS THE WIND SHIFTS SOUTH. EXPECTING PORT SHELDON TO COME UP OVER THE NEXT 1-3 HOURS. WINDS AND WAVES SHOULD BE FAIRLY TAME AFTER THIS EVENING AS HIGH PRESSURE BUILDS IN THE NEXT COUPLE DAYS. && .HYDROLOGY... ISSUED AT 139 PM EDT THU APR 30 2015 RIVERS ARE RUNNING NEAR TO BELOW NORMAL. NO ISSUES ARE EXPECTED THROUGH THE WEEKEND. WE ARE MONITORING THE POTENTIAL FOR OVER AN INCH OF RAINFALL DURING THE FIRST HALF OF NEXT WEEK. CONFIDENCE IS CURRENTLY NOT HIGH ON WHERE THE AXIS OF HEAVIEST RAIN WILL BE. WITH THE GREEN-UP UNDERWAY... PLANTS AND SOIL ARE ABLE TO ABSORB A GREATER AMOUNT OF RAIN THAN EARLIER IN THE SPRING. THIS WILL BUFFER RIVER RESPONSE TO SOME EXTENT. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR LMZ847>849. SMALL CRAFT ADVISORY UNTIL 3 AM EDT FRIDAY FOR LMZ844>846. && $$ SYNOPSIS...DUKE SHORT TERM...DUKE LONG TERM...JAM AVIATION...JAM HYDROLOGY...CAS MARINE...DUKE
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
137 PM EDT THU APR 30 2015 .AVIATION... A DEFORMATION FORCED RAIN BAND OVER THE DETROIT TAF SITES IS PIVOTING OVER HEAD WHICH WILL DELAY ITS EXIT SOUTHWARD THIS AFTERNOON. ONE ADDITIONAL BAND OF RAIN IS CURRENTLY DEVELOPING OVER SOUTHERN ONTARIO WHICH WILL GET PULLED INTO SOUTHEAST LOWER MI THIS EVENING BEFORE ALSO DROPPING SOUTHWARD OUT OF THE AREA. THESE FEATURES ARE LEADING TO VARIABLE CONDITIONS ACROSS THE REGION AS SUBSIDENCE SINKING INTO NORTHERN AND MID MICHIGAN ERODE THE CLOUD FIELD OVER THOSE AREAS. THE TREND THROUGH THE OVERNIGHT WILL BE FOR SUBSIDENCE TO CONTINUE SOUTHWARD LEADING TO VFR CONDITIONS AT ALL SITES OVERNIGHT AND INTO FRIDAY. MAINLY VFR CONDITIONS THROUGH THE PERIOD OUTSIDE OF THE TWO AFOREMENTIONED MVFR RAIN BANDS. FOR DTW...LIGHT MVFR RAIN SHOWERS WILL BE EXITING RIGHT AROUND 18Z SO WILL BE LEFT OUT OF THE FORECAST. A SECOND BAND OF SHOWERS LOOKS TO TARGET THE AREA LATE THIS EVENING BETWEEN ABOUT 21-00Z. CONFIDENCE IS NOT HIGH WITH TIMING AS THE BAND IS JUST NOW COMING TOGETHER SO WILL CONTINUE TO TEMPO IT IN. CIGS WILL GO VFR OVERNIGHT AS SUBSIDENCE RESULTS IN ONLY CIRRUS DEBRIS. //DTW THRESHOLD PROBABILITIES... * MEDIUM FOR CIGS BELOW 5KFT THIS AFTERNOON AND AGAIN THIS EVENING. * HIGH FOR CIGS ABOVE 5KFT TONIGHT AND TOMORROW. && .PREV DISCUSSION...ISSUED 358 AM EDT THU APR 30 2015 SHORT TERM...TODAY AND TONIGHT THE TIGHT MIDLEVEL POTENTIAL VORTICITY ANOMALY AND ACCOMPANYING MIDLEVEL COLD POOL CONTINUES TO DROP STRAIGHT SOUTHWARD ALONG THE EASTERN SHORELINE OF LAKE MICHIGAN THIS MORNING. CONVERGENCE OF THE MASS FIELD IMMEDIATELY ALONG THE FORWARD EASTERN FLANK OF THIS COLD POOL AND INCREASING EASTERLY SYSTEM RELATIVE FLOW HAS RESULTED IN POSITIVE CONTRIBUTIONS OF BOTH TILTING AND MIDLEVEL STRETCHING DEFORMATION. THE COMBINED FORCING HAS RESULTED IN A WIDESPREAD COVERAGE OF SHOWERS OVER SOUTHEASTERN MICHGIAN FOR MUCH OF THE NIGHT. THE RECENT TREND OF THE RADAR OUTPUT HAS BEEN FOR A FOCUS OF THE RAIN SHOWERS DOWN TO DETROIT AND THE RIVERS. RADAR ECHOES HAVE BEEN HOLDING STEADY IN ADDITION TO BANDS OF CONTINUED CLOUDTOP COOLING IN IR IMAGERY. ALTHOUGH RADAR ESTIMATES LIKELY CONTAIN SOME BRIGHTBAND CONTAMINATION...SOME AREAS OVER WAYNE AND MONROE COUNTIES WILL LIKELY REPORT RAINFALL AMOUNTS OF GREATER THAN .5 INCH. AS A RESULT...INCREASED POPS TO CATEGORICAL THROUGH 12Z. MODEL DATA SUPPORTS BOTH CENTERING AND CONTRACTING THE STRETCHING DEFORMATION AXIS OVER EXTREME EASTERN PORTIONS OF THE CWA AROUND 12Z...BEFORE SLOWLY PIVOTING TO THE SOUTHWEST DURING THE LATE MORNING HOURS. ALL THINGS CONSIDERED...THE SOLUTION SPACE OF THE NAM/RUC/ECWMF AND HRRR HAVE THE MOST TRUSTWORTHY OF OUTPUT WITH REGARDS TO QPF PLACEMENT. THEREFORE...EXPECT A WIDESPREAD COVERAGE OF RAIN SHOWERS TO HOLD FIRM THROUGH 14 OR 15Z...BEFORE SCATTERING OUT. SOME HI RESOLUTION CONVECTION ALLOWING NWP ALONG WITH THE HRRR IS ADVERTISING A SOLUTION FOR A RAIN SHOWER CHANCE ONCE AGAIN DURING THE LATE AFTERNOON. THE SOLUTIONS ARE SUGGESTING THAT RAIN ACTIVITY OVER PORTIONS OF PENNSYLVANIA RESIDE WITHIN A MOISTURE AXIS THAT WILL GET DRAWN NORTHWARD AND THEN ADVECTED WESTWARD TOWARND THE LAKE MICHIGAN PV ANOMALY. THEREFORE...IT IS THIS ACTIVITY THAT COULD BACKDOOR ACROSS THE DETROIT RIVER/LAKE ST CLAIR SOMETIME AFTER 20Z THIS AFTERNOON. CURRENT RADAR MOSAIC SHOWS THIS SHOWER ACTIVITY TO BE STRUGGLING EARLY THIS MORNING...AND WILL ONLY ACCOUNT FOR THIS WITH A CHANCE POP BETWEEN 16-00Z. WITH THE OPAQUE CLOUD...TRENDED HIGH TEMPERATURES DOWNWARD A COUPLE OF DEGREES FOR THE SOUTHERN 1/3RD OF THE CWA. SUBSIDENCE WILL WRAP BACK INTO SOUTHEASTERN MICHIGAN QUICKLY AFTER 00Z TONIGHT. THIS IS EXPECTED TO PUSH ANY REMAINING PRECIPITATION POTENTIAL TO SOUTH OF THE OHIO/MICHIGAN STATELINE. WILL ACTUALLY SEE SOME MINOR WARM AIR ADVECTION OVERNIGHT...KEEPING LOWS IN THE 40S FOR MANY LOCATIONS (RIGHT AROUND AVERAGE). LONG TERM... WARMER WEATHER WILL DEVELOP LATE THIS WEEK INTO THE WEEKEND AS THE CURRENT UPPER LOW MOVES TO THE EAST COAST AND BEYOND AND UPPER LEVEL HEIGHTS BEGIN TO BUILD OVER THE AREA AS THE MAIN WESTERLIES REFOCUS OVER THE NORTHERN PLAINS AND SOUTHERN CANADA AND UPPER TROUGHING OVER THE GREAT LAKES IS REPLACED BY MODEST ZONAL FLOW. WITH THE STORM TRACK SO FAR NORTH INTO THE WEEKEND...MAINLY DRY WEATHER IS EXPECTED INTO MUCH OF SUNDAY WITH TEMPERATURES BUILDING FROM THE MID 60S FRIDAY TO 70 OR BETTER FOR MOST LOCATIONS BOTH SATURDAY AND SUNDAY. WHILE MILD WEATHER WILL PERSIST INTO MUCH OF NEXT WEEK...THE CHANCE OF RAIN...AND THUNDERSTORMS AT TIMES...WILL INCREASE AS A SERIES OF STRONG SHORTWAVE BUCKLE THE STRONG ZONAL FLOW OVER MID NOAM SLIGHTLY AND ALLOWS THE MEAN FRONTAL BOUNDARY DRAPED ALONG THE SWATH OF WESTERLIES TO PUSH SOUTH INTO THE AREA SUNDAY NIGHT...WHERE IT WILL REMAIN UNTIL MIDWEEK. BY THE END OF THE FORECAST PERIOD...A MORE SUBSTANTIAL WESTERN UPPER TROUGH IS EXPECTED TO AMPLIFY AS SHORTWAVE ENERGY DIGGING INTO THE PACIFIC NORTHWEST AND BRITISH COLUMBIA PICK UP AN UPPER LOW MEANDERING OVER CALIFORNIA/FOUR CORNERS. DOWNSTREAM OF THIS FEATURE...UPPER LEVEL HEIGHTS WILL BUILD OVER THE AREA AND MAINTAIN MILD WEATHER GENERALLY ABOVE AVERAGE BY SEVERAL DEGREES. DURING THIS TIME...SHOWER AND THUNDERSTORM CHANCES WILL BECOME MORE SCATTERED AS THE FOCUS OF MORE ORGANIZED CONVECTION SHIFTS BACK NORTH FOR AT LEAST A DAY OR TWO LATE NEXT WEEK. WITH THE TRANSITION TO A MORE MODERATE PATTERN...THERE IS LITTLE TO NO CHANCE OF FROST OVER FREEZING TEMPERATURES FROM THIS WEEKEND INTO MID/LATE NEXT WEEK. MARINE... NORTH TO NORTHEAST FLOW WILL DEVELOP TONIGHT AS AN UPPER LEVEL LOW PRESSURE SYSTEM DROPS SOUTH THROUGH THE CENTRAL GREAT LAKES. THIS FLOW WILL PERSIST THROUGH FRIDAY AS THE LOW PIVOTS EAST TO SOUTHEAST TO THE MID ATLANTIC SHORELINE. WHILE WINDS WILL REMAIN RELATIVELY LIGHT...10 TO 15 KNOT FLOW LATE THURSDAY AND THURSDAY NIGHT WITH GUSTS TO 20 KNOTS WILL PRODUCE SOME ENHANCED WAVE DEVELOPMENT. THAT SAID...WAVES SHOULD STILL REMAIN BELOW SMALL CRAFT CRITERION FOR THE NEARSHORE WATERS. NORTHERLY FLOW WILL BECOME LIGHT AND VARIABLE LATE FRIDAY AND FRIDAY NIGHT AS A SMALL AREA OF SURFACE HIGH PRESSURE SETTLES THROUGH THE AREA. LIGHT SOUTH FLOW WILL THEN BECOME ESTABLISHED HEADING INTO THE WEEKEND AS THIS HIGH SHIFTS TO THE EAST. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DRK SHORT TERM...CB LONG TERM....DG MARINE.......DG YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
657 AM EDT THU APR 30 2015 .AVIATION... LOCALIZED LOW LEVEL DYNAMICS UNDER BROADER DEFORMATION FORCING WILL STALL OUT OVER FAR SOUTHEASTERN MICHIGAN THIS MORNING. BY LATE THIS MORNING OR EARLY AFTERNOON...THE UPPER LEVEL FEATURE RESPONSIBLE FOR THIS PRECIPITATION WILL HAVE PASSED FAR ENOUGH SOUTH TO PIVOT THE BAND OF RAIN SHOWERS BACK TO THE SOUTH AND WEST. WILL CONTINUE TO CALL FOR PREVAILING RAIN AT THE DETROIT TERMINALS UNTIL 15Z BEFORE DRYING THINGS OUT. MODEL DATA DOES SUPPORT BRINGING AN AREA OF ENHANCED MOISTURE BACK INTO SOUTHEASTERN MICHIGAN FROM THE EAST AFTER 20Z. ACCOUNTED FOR THIS POTENTIAL WITH A TEMPO GROUPING. FOR DTW...FORCING WILL STALL OUT OVER THE DETROIT TERMINALS THIS MORNING BEFORE MIGRATING WESTWARD. CIGS ARE EXPECTED TO FALL AND REMAIN BELOW 5 KFT AGL MOMENTARILY. WIDESPREAD LIGHT RAIN SHOWERS WITH POCKETS OF MODERATE RAINFALL ARE EXPECTED TO PERSIST TO AROUND 15Z. VFR CONDITIONS TO RETURN LATE THURSDAY. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CIGS AOB 5KFT THIS MORNING. * LOW FOR CIGS BACK ABOVE 5KFT BY THURSDAY AFTERNOON. && .PREV DISCUSSION...ISSUED 358 AM EDT THU APR 30 2015 SHORT TERM...TODAY AND TONIGHT THE TIGHT MIDLEVEL POTENTIAL VORTICITY ANOMALY AND ACCOMPANYING MIDLEVEL COLD POOL CONTINUES TO DROP STRAIGHT SOUTHWARD ALONG THE EASTERN SHORELINE OF LAKE MICHIGAN THIS MORNING. CONVERGENCE OF THE MASS FIELD IMMEDIATELY ALONG THE FORWARD EASTERN FLANK OF THIS COLD POOL AND INCREASING EASTERLY SYSTEM RELATIVE FLOW HAS RESULTED IN POSITIVE CONTRIBUTIONS OF BOTH TILTING AND MIDLEVEL STRETCHING DEFORMATION. THE COMBINED FORCING HAS RESULTED IN A WIDESPREAD COVERAGE OF SHOWERS OVER SOUTHEASTERN MICHGIAN FOR MUCH OF THE NIGHT. THE RECENT TREND OF THE RADAR OUTPUT HAS BEEN FOR A FOCUS OF THE RAIN SHOWERS DOWN TO DETROIT AND THE RIVERS. RADAR ECHOES HAVE BEEN HOLDING STEADY IN ADDITION TO BANDS OF CONTINUED CLOUDTOP COOLING IN IR IMAGERY. ALTHOUGH RADAR ESTIMATES LIKELY CONTAIN SOME BRIGHTBAND CONTAMINATION...SOME AREAS OVER WAYNE AND MONROE COUNTIES WILL LIKELY REPORT RAINFALL AMOUNTS OF GREATER THAN .5 INCH. AS A RESULT...INCREASED POPS TO CATEGORICAL THROUGH 12Z. MODEL DATA SUPPORTS BOTH CENTERING AND CONTRACTING THE STRETCHING DEFORMATION AXIS OVER EXTREME EASTERN PORTIONS OF THE CWA AROUND 12Z...BEFORE SLOWLY PIVOTING TO THE SOUTHWEST DURING THE LATE MORNING HOURS. ALL THINGS CONSIDERED...THE SOLUTION SPACE OF THE NAM/RUC/ECWMF AND HRRR HAVE THE MOST TRUSTWORTHY OF OUTPUT WITH REGARDS TO QPF PLACEMENT. THEREFORE...EXPECT A WIDESPREAD COVERAGE OF RAIN SHOWERS TO HOLD FIRM THROUGH 14 OR 15Z...BEFORE SCATTERING OUT. SOME HI RESOLUTION CONVECTION ALLOWING NWP ALONG WITH THE HRRR IS ADVERTISING A SOLUTION FOR A RAIN SHOWER CHANCE ONCE AGAIN DURING THE LATE AFTERNOON. THE SOLUTIONS ARE SUGGESTING THAT RAIN ACTIVITY OVER PORTIONS OF PENNSYLVANIA RESIDE WITHIN A MOISTURE AXIS THAT WILL GET DRAWN NORTHWARD AND THEN ADVECTED WESTWARD TOWARND THE LAKE MICHIGAN PV ANOMALY. THEREFORE...IT IS THIS ACTIVITY THAT COULD BACKDOOR ACROSS THE DETROIT RIVER/LAKE ST CLAIR SOMETIME AFTER 20Z THIS AFTERNOON. CURRENT RADAR MOSAIC SHOWS THIS SHOWER ACTIVITY TO BE STRUGGLING EARLY THIS MORNING...AND WILL ONLY ACCOUNT FOR THIS WITH A CHANCE POP BETWEEN 16-00Z. WITH THE OPAQUE CLOUD...TRENDED HIGH TEMPERATURES DOWNWARD A COUPLE OF DEGREES FOR THE SOUTHERN 1/3RD OF THE CWA. SUBSIDENCE WILL WRAP BACK INTO SOUTHEASTERN MICHIGAN QUICKLY AFTER 00Z TONIGHT. THIS IS EXPECTED TO PUSH ANY REMAINING PRECIPITATION POTENTIAL TO SOUTH OF THE OHIO/MICHIGAN STATELINE. WILL ACTUALLY SEE SOME MINOR WARM AIR ADVECTION OVERNIGHT...KEEPING LOWS IN THE 40S FOR MANY LOCATIONS (RIGHT AROUND AVERAGE). LONG TERM... WARMER WEATHER WILL DEVELOP LATE THIS WEEK INTO THE WEEKEND AS THE CURRENT UPPER LOW MOVES TO THE EAST COAST AND BEYOND AND UPPER LEVEL HEIGHTS BEGIN TO BUILD OVER THE AREA AS THE MAIN WESTERLIES REFOCUS OVER THE NORTHERN PLAINS AND SOUTHERN CANADA AND UPPER TROUGHING OVER THE GREAT LAKES IS REPLACED BY MODEST ZONAL FLOW. WITH THE STORM TRACK SO FAR NORTH INTO THE WEEKEND...MAINLY DRY WEATHER IS EXPECTED INTO MUCH OF SUNDAY WITH TEMPERATURES BUILDING FROM THE MID 60S FRIDAY TO 70 OR BETTER FOR MOST LOCATIONS BOTH SATURDAY AND SUNDAY. WHILE MILD WEATHER WILL PERSIST INTO MUCH OF NEXT WEEK...THE CHANCE OF RAIN...AND THUNDERSTORMS AT TIMES...WILL INCREASE AS A SERIES OF STRONG SHORTWAVE BUCKLE THE STRONG ZONAL FLOW OVER MID NOAM SLIGHTLY AND ALLOWS THE MEAN FRONTAL BOUNDARY DRAPED ALONG THE SWATH OF WESTERLIES TO PUSH SOUTH INTO THE AREA SUNDAY NIGHT...WHERE IT WILL REMAIN UNTIL MIDWEEK. BY THE END OF THE FORECAST PERIOD...A MORE SUBSTANTIAL WESTERN UPPER TROUGH IS EXPECTED TO AMPLIFY AS SHORTWAVE ENERGY DIGGING INTO THE PACIFIC NORTHWEST AND BRITISH COLUMBIA PICK UP AN UPPER LOW MEANDERING OVER CALIFORNIA/FOUR CORNERS. DOWNSTREAM OF THIS FEATURE...UPPER LEVEL HEIGHTS WILL BUILD OVER THE AREA AND MAINTAIN MILD WEATHER GENERALLY ABOVE AVERAGE BY SEVERAL DEGREES. DURING THIS TIME...SHOWER AND THUNDERSTORM CHANCES WILL BECOME MORE SCATTERED AS THE FOCUS OF MORE ORGANIZED CONVECTION SHIFTS BACK NORTH FOR AT LEAST A DAY OR TWO LATE NEXT WEEK. WITH THE TRANSITION TO A MORE MODERATE PATTERN...THERE IS LITTLE TO NO CHANCE OF FROST OVER FREEZING TEMPERATURES FROM THIS WEEKEND INTO MID/LATE NEXT WEEK. MARINE... NORTH TO NORTHEAST FLOW WILL DEVELOP TONIGHT AS AN UPPER LEVEL LOW PRESSURE SYSTEM DROPS SOUTH THROUGH THE CENTRAL GREAT LAKES. THIS FLOW WILL PERSIST THROUGH FRIDAY AS THE LOW PIVOTS EAST TO SOUTHEAST TO THE MID ATLANTIC SHORELINE. WHILE WINDS WILL REMAIN RELATIVELY LIGHT...10 TO 15 KNOT FLOW LATE THURSDAY AND THURSDAY NIGHT WITH GUSTS TO 20 KNOTS WILL PRODUCE SOME ENHANCED WAVE DEVELOPMENT. THAT SAID...WAVES SHOULD STILL REMAIN BELOW SMALL CRAFT CRITERION FOR THE NEARSHORE WATERS. NORTHERLY FLOW WILL BECOME LIGHT AND VARIABLE LATE FRIDAY AND FRIDAY NIGHT AS A SMALL AREA OF SURFACE HIGH PRESSURE SETTLES THROUGH THE AREA. LIGHT SOUTH FLOW WILL THEN BECOME ESTABLISHED HEADING INTO THE WEEKEND AS THIS HIGH SHIFTS TO THE EAST. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....CB SHORT TERM...CB LONG TERM....DG MARINE.......DG YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
358 AM EDT THU APR 30 2015 .SHORT TERM...TODAY AND TONIGHT THE TIGHT MIDLEVEL POTENTIAL VORTICITY ANOMALY AND ACCOMPANYING MIDLEVEL COLD POOL CONTINUES TO DROP STRAIGHT SOUTHWARD ALONG THE EASTERN SHORELINE OF LAKE MICHIGAN THIS MORNING. CONVERGENCE OF THE MASS FIELD IMMEDIATELY ALONG THE FORWARD EASTERN FLANK OF THIS COLD POOL AND INCREASING EASTERLY SYSTEM RELATIVE FLOW HAS RESULTED IN POSITIVE CONTRIBUTIONS OF BOTH TILTING AND MIDLEVEL STRETCHING DEFORMATION. THE COMBINED FORCING HAS RESULTED IN A WIDESPREAD COVERAGE OF SHOWERS OVER SOUTHEASTERN MICHGIAN FOR MUCH OF THE NIGHT. THE RECENT TREND OF THE RADAR OUTPUT HAS BEEN FOR A FOCUS OF THE RAIN SHOWERS DOWN TO DETROIT AND THE RIVERS. RADAR ECHOES HAVE BEEN HOLDING STEADY IN ADDITION TO BANDS OF CONTINUED CLOUDTOP COOLING IN IR IMAGERY. ALTHOUGH RADAR ESTIMATES LIKELY CONTAIN SOME BRIGHTBAND CONTAMINATION...SOME AREAS OVER WAYNE AND MONROE COUNTIES WILL LIKELY REPORT RAINFALL AMOUNTS OF GREATER THAN .5 INCH. AS A RESULT...INCREASED POPS TO CATEGORICAL THROUGH 12Z. MODEL DATA SUPPORTS BOTH CENTERING AND CONTRACTING THE STRETCHING DEFORMATION AXIS OVER EXTREME EASTERN PORTIONS OF THE CWA AROUND 12Z...BEFORE SLOWLY PIVOTING TO THE SOUTHWEST DURING THE LATE MORNING HOURS. ALL THINGS CONSIDERED...THE SOLUTION SPACE OF THE NAM/RUC/ECWMF AND HRRR HAVE THE MOST TRUSTWORTHY OF OUTPUT WITH REGARDS TO QPF PLACEMENT. THEREFORE...EXPECT A WIDESPREAD COVERAGE OF RAIN SHOWERS TO HOLD FIRM THROUGH 14 OR 15Z...BEFORE SCATTERING OUT. SOME HI RESOLUTION CONVECTION ALLOWING NWP ALONG WITH THE HRRR IS ADVERTISING A SOLUTION FOR A RAIN SHOWER CHANCE ONCE AGAIN DURING THE LATE AFTERNOON. THE SOLUTIONS ARE SUGGESTING THAT RAIN ACTIVITY OVER PORTIONS OF PENNSYLVANIA RESIDE WITHIN A MOISTURE AXIS THAT WILL GET DRAWN NORTHWARD AND THEN ADVECTED WESTWARD TOWARND THE LAKE MICHIGAN PV ANOMALY. THEREFORE...IT IS THIS ACTIVITY THAT COULD BACKDOOR ACROSS THE DETROIT RIVER/LAKE ST CLAIR SOMETIME AFTER 20Z THIS AFTERNOON. CURRENT RADAR MOSAIC SHOWS THIS SHOWER ACTIVITY TO BE STRUGGLING EARLY THIS MORNING...AND WILL ONLY ACCOUNT FOR THIS WITH A CHANCE POP BETWEEN 16-00Z. WITH THE OPAQUE CLOUD...TRENDED HIGH TEMPERATURES DOWNWARD A COUPLE OF DEGREES FOR THE SOUTHERN 1/3RD OF THE CWA. SUBSIDENCE WILL WRAP BACK INTO SOUTHEASTERN MICHIGAN QUICKLY AFTER 00Z TONIGHT. THIS IS EXPECTED TO PUSH ANY REMAINING PRECIPITATION POTENTIAL TO SOUTH OF THE OHIO/MICHIGAN STATELINE. WILL ACTUALLY SEE SOME MINOR WARM AIR ADVECTION OVERNIGHT...KEEPING LOWS IN THE 40S FOR MANY LOCATIONS (RIGHT AROUND AVERAGE). && .LONG TERM... WARMER WEATHER WILL DEVELOP LATE THIS WEEK INTO THE WEEKEND AS THE CURRENT UPPER LOW MOVES TO THE EAST COAST AND BEYOND AND UPPER LEVEL HEIGHTS BEGIN TO BUILD OVER THE AREA AS THE MAIN WESTERLIES REFOCUS OVER THE NORTHERN PLAINS AND SOUTHERN CANADA AND UPPER TROUGHING OVER THE GREAT LAKES IS REPLACED BY MODEST ZONAL FLOW. WITH THE STORM TRACK SO FAR NORTH INTO THE WEEKEND...MAINLY DRY WEATHER IS EXPECTED INTO MUCH OF SUNDAY WITH TEMPERATURES BUILDING FROM THE MID 60S FRIDAY TO 70 OR BETTER FOR MOST LOCATIONS BOTH SATURDAY AND SUNDAY. WHILE MILD WEATHER WILL PERSIST INTO MUCH OF NEXT WEEK...THE CHANCE OF RAIN...AND THUNDERSTORMS AT TIMES...WILL INCREASE AS A SERIES OF STRONG SHORTWAVE BUCKLE THE STRONG ZONAL FLOW OVER MID NOAM SLIGHTLY AND ALLOWS THE MEAN FRONTAL BOUNDARY DRAPED ALONG THE SWATH OF WESTERLIES TO PUSH SOUTH INTO THE AREA SUNDAY NIGHT...WHERE IT WILL REMAIN UNTIL MIDWEEK. BY THE END OF THE FORECAST PERIOD...A MORE SUBSTANTIAL WESTERN UPPER TROUGH IS EXPECTED TO AMPLIFY AS SHORTWAVE ENERGY DIGGING INTO THE PACIFIC NORTHWEST AND BRITISH COLUMBIA PICK UP AN UPPER LOW MEANDERING OVER CALIFORNIA/FOUR CORNERS. DOWNSTREAM OF THIS FEATURE...UPPER LEVEL HEIGHTS WILL BUILD OVER THE AREA AND MAINTAIN MILD WEATHER GENERALLY ABOVE AVERAGE BY SEVERAL DEGREES. DURING THIS TIME...SHOWER AND THUNDERSTORM CHANCES WILL BECOME MORE SCATTERED AS THE FOCUS OF MORE ORGANIZED CONVECTION SHIFTS BACK NORTH FOR AT LEAST A DAY OR TWO LATE NEXT WEEK. WITH THE TRANSITION TO A MORE MODERATE PATTERN...THERE IS LITTLE TO NO CHANCE OF FROST OVER FREEZING TEMPERATURES FROM THIS WEEKEND INTO MID/LATE NEXT WEEK. && .MARINE... NORTH TO NORTHEAST FLOW WILL DEVELOP TONIGHT AS AN UPPER LEVEL LOW PRESSURE SYSTEM DROPS SOUTH THROUGH THE CENTRAL GREAT LAKES. THIS FLOW WILL PERSIST THROUGH FRIDAY AS THE LOW PIVOTS EAST TO SOUTHEAST TO THE MID ATLANTIC SHORELINE. WHILE WINDS WILL REMAIN RELATIVELY LIGHT...10 TO 15 KNOT FLOW LATE THURSDAY AND THURSDAY NIGHT WITH GUSTS TO 20 KNOTS WILL PRODUCE SOME ENHANCED WAVE DEVELOPMENT. THAT SAID...WAVES SHOULD STILL REMAIN BELOW SMALL CRAFT CRITERION FOR THE NEARSHORE WATERS. NORTHERLY FLOW WILL BECOME LIGHT AND VARIABLE LATE FRIDAY AND FRIDAY NIGHT AS A SMALL AREA OF SURFACE HIGH PRESSURE SETTLES THROUGH THE AREA. LIGHT SOUTH FLOW WILL THEN BECOME ESTABLISHED HEADING INTO THE WEEKEND AS THIS HIGH SHIFTS TO THE EAST. && .AVIATION...ISSUED 140 AM EDT THU APR 30 2015 LOCALIZED LOW LEVEL DYNAMICS UNDER BROADER DEFORMATION FORCING HAS RESULTED IN WIDESPREAD SHOWERS OVER SOUTHEASTERN MICHIGAN TONIGHT. CIGS ARE STILL STRUGGLING WITH DRY AIR IN THE LOWER TROPOSPHERE. GIVEN ADDITIONAL TIGHTENING OF THE THERMAL AND MOISTURE GRADIENTS OVERHEAD IN ADDITION TO TOP DOWN SATURATION...MVFR CIGS ARE STILL EXPECTED TO DEVELOP DURING THE COURSE OF THE NIGHT. THE UPPER LEVEL WAVE RESPONSIBLE FOR THIS INCREASE IN ASCENT WILL DIVE STRAIGHT SOUTHWARD OVER LAKE MICHIGAN TONIGHT. THE SOUTHERN TERMINALS WILL REMAIN WITHIN A PIVOT POINT WHICH SUPPORTS A CONTINUATION OF SHOWERS THROUGH 14-15Z. MODEL DATA THEN SUPPORTS A SIGNIFICANT DOWNTREND IN THE COVERAGE OF SHOWERS FOR THE AFTERNOON HOURS. HOWEVER...MODELS DO SUPPORT PESKY SHOWERS HANGING AROUND FOR THE AFTERNOON ACROSS THE DETROIT TERMINALS AS THE MOISTURE AXIS WILL BE SLOW TO STRIP OUT. FOR DTW...FORCING WILL MAXIMIZE OVER THE DETROIT TERMINAL OVER THE NEXT 6 HOURS. CIGS ARE EXPECTED TO FALL AND REMAIN BELOW 5 KFT AGL MOMENTARILLY. WIDESPREAD LIGHT RAIN SHOWERS WITH POCKETS OF MODERATE RAINFALL ARE EXPECTED TO PERSIST TO AROUND 15Z. VFR CONDITIONS TO RETURN LATE THURSDAY. //DTW THRESHOLD PROBABILITIES... * HIGH FOR CIGS AOB 5KFT THIS MORNING. * LOW FOR CIGS BACK ABOVE 5KFT BY THURSDAY AFTERNOON. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...CB LONG TERM....DG MARINE.......DG AVIATION.....CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
619 PM CDT FRI MAY 1 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 242 PM CDT FRI MAY 1 2015 WEAK HIGH PRESSURE OVERHEAD WILL PIVOT MOISTURE NORTHWARD THIS EVENING. THE RAP AND HRRR SUGGEST WEAKLY ORGANIZED DISCRETE SHOWER AND THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON AND THIS EVENING. OTHER THAN GUSTY OUTFLOW WINDS...NO SIGNIFICANT WEATHER IS EXPECTED AND NO STORMS SHOULD REACH SEVERE LIMITS. A WARM FRONT WILL LIFT NORTH AS THE HIGH MOVES EAST LATER THIS EVENING. DEW POINTS SHOULD INCREASE TO AROUND 50F BY MID SATURDAY MORNING. THE NAM CONTINUES TO ADVERTISE A FAIRLY ROBUST DRYLINE SURGE SATURDAY AFTN FOCUSED ALONG HIGHWAY 20 WEST OF VALENTINE. DESTABILIZATION IS POSSIBLE ACROSS PINE RIDGE AND THE WRN SANDHILLS SOUTH THROUGH IMPERIAL AROUND 21Z. THE NAM DID SHOW ABOUT 20 TO 30 J/KG OF INHIBITION SO POPS ARE ISOLATED. MLCAPE NEAR 1500 J/KG AND BULK SHEAR TO 450 MB OF 30 TO 35 KT COULD SUPPORT AN ISOLATED STRONG OR SEVERE STORM DURING THE PEAK HEATING PERIOD. THE BULK RICHARDSON NUMBER IS CLOSE TO 50 AT THIS TIME AND SHEAR PROFILES LOOK SMOOTHLY CURVED. LOWS TONIGHT FALL TO THE UPPER 40S TO AROUND 50. HIGHS SATURDAY RISE INTO THE LOW TO MID 80S WITH MIXING HEIGHTS NEAR 700 MB. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 242 PM CDT FRI MAY 1 2015 A TRAJECTORY FROM THE PACIFIC SOUTHWEST CONTINUES SATURDAY NIGHT WHILE A TRAJECTORY FROM THE TEXAS GULF COAST CROSSES CENTRAL AND EASTERN NEBRASKA. THE PACIFIC MOISTURE WILL THUS BE IN PLACE WHEN A SURFACE FRONT COMES THROUGH SUNDAY MORNING. THE TIMING OF THE FRONT IS NOT REAL FAVORABLE FOR THUNDERSTORMS. HOWEVER...THE LIFT SHOULD BE SUFFICIENT TO TRIGGER ISOLATED CONVECTION BY SUNDAY EVENING WITH IT CONTINUING SUNDAY NIGHT AND MONDAY IN CENTRAL AND SOUTHWEST NEBRASKA. WITH THE FRONT BECOMING STATIONARY ACROSS CENTRAL KANSAS...SOME UPGLIDE WILL CONTINUE INTO MONDAY AFTERNOON AND EVENING. THIS CAN BE SEEN WITH THE PRESSURE LEVELS AND MOISTURE TRANSPORT VECTORS OVER CENTRAL...SOUTH CENTRAL AND SOUTHWEST NEBRASKA ON THE 300K AND 305K SURFACES. THE INSTABILITY...AT ABOUT 0C FOR THE 800MB BASED LIFTED INDEX...IS EXPECTED TO BE MARGINAL. AS A RESULT...ONLY A FEW EMBEDDED THUNDERSTORMS ARE EXPECTED IN AN AREA OF GENERAL RAIN OR SHOWERS. WITH PRECIPITABLE WATER EXCEEDING 0.7 INCH...SIGNIFICANT PRECIPITATION TOTALS CAN BE EXPECTED ALONG A BROKEN BOW-NORTH PLATTE-IMPERIAL LINE AND SOUTH WITH AMOUNTS DROPPING OFF SHARPLY NORTH OF THAT LINE. AS THE ACTIVE UPPER PATTERN CONTINUES...ANOTHER NEGATIVELY TILTED TROUGH PIVOTS ACROSS THE NORTHERN PLAINS. AHEAD OF THE SYSTEM...A GOOD MOISTURE TRAJECTORY CONTINUES TUESDAY NIGHT AND WEDNESDAY FROM THE TEXAS GULF COAST INTO NEBRASKA AND THE DAKOTAS. AS THE CYCLONE MAKES ITS WAY NORTHWARD...WARM ADVECTION ALOFT WILL CONTINUE BRINGING WIDESPREAD RAINFALL TO WESTERN NEBRASKA. BY EARLY THURSDAY...THE DRY INTRUSION OVERTAKES THE CYCLONE AND BRINGS AN END TO THE PRECIPITATION IN CENTRAL AND WESTERN NEBRASKA. THERE IS SIGNIFICANT DISAGREEMENT BETWEEN THE 00Z ECMWF AND THE 12Z GFS40 WITH THIS SYSTEM...SO CONFIDENCE IS NOT HIGH IN THE SOLUTIONS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 620 PM CDT FRI MAY 1 2015 VFR CONDITIONS THE NEXT 24 HOURS FOR THE KLBF AND KVTN TERMINALS. LIGHT SOUTHEAST WINDS TONIHGT AROUND 5 MPH WILL BECOME SOUTH AND INCREASE TO 18010G18KT AFTER 17Z. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...SPRINGER AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
344 AM EDT THU APR 30 2015 .SYNOPSIS... VARIABLE CLOUDS, DRY WEATHER AND SEASONABLY MILD TEMPERATURES WILL BE THE RULE OF THUMB ACROSS THE REGION THROUGH SATURDAY AS WEAK HIGH PRESSURE REMAINS ACROSS THE REGION. TEMPERATURES WARM CONSIDERABLY ABOVE AVERAGE FOR SUNDAY INTO MONDAY AS SOUTHERLY WINDS RETURN TO THE REGION. THE NEXT CHANCE FOR SIGNIFICANT PRECIPITATION WILL OCCUR MONDAY NIGHT INTO TUESDAY AS A COLD FRONT SAGS INTO THE REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 330 AM EDT THURSDAY...ANOTHER PLEASANT MID-SPRING DAY ON TAP AS WEAK HIGH PRESSURE REMAINS SANDWICHED ACROSS THE REGION BETWEEN MARITIME LOW PRESSURE AND ADDITIONAL UPPER ENERGY DROPPING SOUTHWARD THROUGH THE GREAT LAKES. INDEED AFTER PERUSAL OF THIS MORNING`S DATA IT APPEARS TODAY WILL NEARLY MIMIC YESTERDAY`S CONDITIONS. MEAN LOW TO MID LEVEL FLOW WILL REMAIN NORTH TO NORTHEASTERLY THROUGH THE DAY WHICH WILL ONCE AGAIN TRANSPORT OCCASIONAL CLOUD COVER OF MARITIME ORIGIN SOUTHWESTWARD INTO THE AREA, CLOUDS BEING MOST PREVALENT ACROSS OUR EASTERN COUNTIES. MEAN 925 MB TEMPERATURES ARE PERHAPS A DEGREE OR TWO WARMER THAN YESTERDAY SO HIGHS RANGING FROM THE LOW TO MID 60S EAST AND MID TO UPPER 60S FROM THE CHAMPLAIN VALLEY WEST LOOKS RIGHT ON TRACK. CAN`T COMPLETELY RULE OUT A STRAY SPRINKLE ACROSS THE HIGHER TERRAIN OF OUR EASTERN VT COUNTIES TODAY, BUT BY AND LARGE DRY WEATHER IS EXPECTED. WINDS NORTH TO NORTHEASTERLY 5 TO 15 MPH, HIGHEST IN THE SLV. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... AS OF 330 AM EDT THURSDAY...MORE OF THE SAME BY TONIGHT THROUGH SATURDAY AS UPPER LOW PRESSURE SLIDES BY TO OUR WEST AND SOUTH AND MEAN PBL FLOW REMAINS GENERALLY LIGHT. WEAK ENERGY SLIDING SOUTHWESTWARD WITHIN THE NORTHEASTERLY MID LEVEL FLOW COULD PRODUCE A STRAY LIGHT SHOWER OR SPRINKLE ACROSS THE SOUTHERN HIGH TERRAIN TONIGHT, OTHERWISE DRY WEATHER SHOULD CONTINUE THROUGH THE PERIOD UNDER VARIABLY CLOUDY/PARTLY CLOUDY SKIES. HIGH TEMPERATURES RANGING THROUGH THE 60S ON FRIDAY, WARMING INTO THE MID 60S TO LOWER 70S BY SATURDAY AS WINDS TREND MORE WESTERLY AND BEGIN TO USHER IN AN AIRMASS MORE CONTINENTAL IN NATURE. DID OPT TO UNDERCUT OVERNIGHT LOWS BY JUST A FEW DEGREES (30S TO LOWER 40S) GIVEN FORECAST OF AT LEAST SOME BREAKS IN THE CLOUD COVER AND RECENT WARM BIAS IN THE BLENDED MOS GUIDANCE. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 341 AM EDT THURSDAY...IT`S GETTING TO BE A BIT OF A BROKEN RECORD WITH THE EXTENDED PERIOD. THE MODELS HAVE BEEN QUITE CONSISTENT WITH THE WARM SEASONALLY DRY CONDITIONS DOMINATED BY AN UPPER LEVEL RIDGE OVER THE WEEKEND GIVING WAY TO A SURFACE FRONTAL SYSTEM ON TUESDAY AFTERNOON THAT LOOKS LIKE IT SHOULD BRING RAIN SHOWERS TO NEARLY THE ENTIRE FORECAST AREA AS IT DROPS SOUTH FROM CANADA. SUNDAY THERE WILL BE A MODERATE UPPER LEVEL RIDGE THAT KEEPS THE AREA NICE HIGH AND DRY AS A SURFACE HIGH CENTERED OVER THE GULF COAST KEEPS THE EASTERN CONUS CALM AND DRY. LOCALLY WE WILL SEE LIGHT TO MODERATE WEST TO SOUTHWEST WINDS ON THE NORTH SIDE OF THE HIGH AND TEMPS SHOULD WARM INTO THE UPPER 60S WITH LOW 70S POSSIBLE IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS. MONDAY THAT HIGH CONTINUES TO DRIFT EASTWARD AND WILL BRING WHAT SHOULD BE A WONDERFUL DAY ON MONDAY WITH TEMPERATURES CREEPING UP INTO THE MID TO UPPER 70S UNDER PARTLY CLOUDY SKIES. FROM THERE A THE UPPER LEVEL FLOW TURNS ZONAL ON TUESDAY AND A WEAK SURFACE FRONT BRINGS A LIKELY CHANCE OF RAIN AS THE FRONT DROPS SOUTH ALONG THE INTERNATIONAL BORDER INTO NORTHERN NEW YORK AND NEW ENGLAND. THAT BIT OF PRECIP WILL CAUSE TEMPS TO COOL SLIGHTLY WHICH WILL BE A TREND NEXT WEEK OF TEMPS ONLY WARMING IN THE MID WEEK TO SEASONAL MID 60S ACROSS THE AREA. LOW TEMPS THROUGH THE PERIOD WILL REMAIN FAIRLY CONSISTENT IN THE UPPER 40S TO LOW 50S WITH THE WARMEST OVERNIGHT LOWS OCCURRING MONDAY NIGHT INTO TUESDAY MORNING BEFORE THE FRONT COOLS THE AREA DOWN SLIGHTLY. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... THROUGH 06Z FRIDAY...EXPECT PREVAILING VFR THROUGH THE FORECAST PERIOD WITH POSSIBLE MVFR STRATUS AT MPV AND MVFR/IFR GROUND FOG AT SLK. CURRENTLY SKIES CONTINUE TO RANGE FROM CLEAR ACROSS MSS/SLK/BTV TO SOME HIGH CLOUD OVER PBG AND OVC MID-CLOUDS FOR MPV. EXPECT THESE TRENDS TO CONTINUE OVERNIGHT. LATEST GUIDANCE CONTINUES TO POINT TO IDEA OF LOWER STRATUS DECK INTRUDING INTO MPV OVERNIGHT AS LOW- LEVEL FLOW BECOMES EASTERLY, THOUGH CURRENT OBSERVATIONS IN THE GULF OF MAINE AND SOUTHERN NEW ENGLAND SHOW OVC VFR CEILINGS 4000-5000 FEET. AT SLK, PROJECTED LOW TEMPERATURES DROP A FEW DEGREES BELOW CROSSOVER TEMPS IN THE MID- 30S UNDER CLEAR SKIES AND LIGHTENING WINDS, SUPPORTING SOME MVFR TO IFR LIGHT FOG IN LIGHT BL FLOW CONDITIONS. I TRENDED BACK THE TIMING OF THE FOG TO MATCH MORE OF THE RAP SOUNDING. GIVEN WE ARE STILL IN THE PRE GREEN UP PHASE THE ONSET OF LIGHT GROUND FOG WILL LIKELY ONLY OCCUR ONCE WE ARE A FEW DEGREES COLDER THAN THE ACTUAL CROSSOVER TEMP. NORTH/NORTHEAST WINDS BECOME LIGHT/VARIABLE OVERNIGHT. VFR CONDITIONS INTO THURSDAY WITH SCT/BKN CLOUDINESS BETWEEN 5000-7000FT. WINDS GENERALLY NORTH/NORTHEAST 5-8 KTS. OUTLOOK 06Z FRIDAY THROUGH MONDAY... 06Z FRIDAY - 12Z MONDAY...GENERALLY VFR CONDITIONS AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE REGION. SOME MVFR SHOWERS ARE POSSIBLE FRIDAY/SATURDAY AS A COASTAL LOW PASSES WELL OFFSHORE. 12Z MONDAY - 00Z TUESDAY...VFR WITH A CHANCE FOR MVFR SHOWERS AS LOW PRESSURE PASSES NORTH OF THE INTL BORDER. && .EQUIPMENT... AS OF 730 PM EDT TUESDAY...THE TEMPERATURE AND DEW POINT HAS BEEN SPORADICALLY MISSING FROM THE AWOS (AUTOMATED WEATHER OBSERVING SYSTEM) AT RUTLAND (KRUT) SOUTHERN VERMONT REGIONAL AIRPORT. THE FAA AOCC HAS BEEN NOTIFIED OF THIS PROBLEM AND HAVE OPENED A TROUBLE TICKET. THE FAA HAS MAINTENANCE RESPONSIBILITY FOR THE AWOS AT RUTLAND VERMONT. NO ESTIMATE IS AVAILABLE AT THIS TIME AS TO WHEN THE TEMPERATURE AND DEW POINT WILL AGAIN CONSISTENTLY BE REPORTED IN THE KRUT OBSERVATIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...JMG SHORT TERM...JMG LONG TERM...DEAL AVIATION...DEAL EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
331 AM EDT THU APR 30 2015 .SYNOPSIS... VARIABLE CLOUDS, DRY WEATHER AND SEASONABLY MILD TEMPERATURES WILL BE THE RULE OF THUMB ACROSS THE REGION THROUGH SATURDAY AS WEAK HIGH PRESSURE REMAINS ACROSS THE REGION. TEMPERATURES WARM CONSIDERABLY ABOVE AVERAGE FOR SUNDAY INTO MONDAY AS SOUTHERLY WINDS RETURN TO THE REGION. THE NEXT CHANCE FOR SIGNIFICANT PRECIPITATION WILL OCCUR MONDAY NIGHT INTO TUESDAY AS A COLD FRONT SAGS INTO THE REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 330 AM EDT THURSDAY...ANOTHER PLEASANT MID-SPRING DAY ON TAP AS WEAK HIGH PRESSURE REMAINS SANDWICHED ACROSS THE REGION BETWEEN MARITIME LOW PRESSURE AND ADDITIONAL UPPER ENERGY DROPPING SOUTHWARD THROUGH THE GREAT LAKES. INDEED AFTER PERUSAL OF THIS MORNING`S DATA IT APPEARS TODAY WILL NEARLY MIMIC YESTERDAY`S CONDITIONS. MEAN LOW TO MID LEVEL FLOW WILL REMAIN NORTH TO NORTHEASTERLY THROUGH THE DAY WHICH WILL ONCE AGAIN TRANSPORT OCCASIONAL CLOUD COVER OF MARITIME ORIGIN SOUTHWESTWARD INTO THE AREA, CLOUDS BEING MOST PREVALENT ACROSS OUR EASTERN COUNTIES. MEAN 925 MB TEMPERATURES ARE PERHAPS A DEGREE OR TWO WARMER THAN YESTERDAY SO HIGHS RANGING FROM THE LOW TO MID 60S EAST AND MID TO UPPER 60S FROM THE CHAMPLAIN VALLEY WEST LOOKS RIGHT ON TRACK. CAN`T COMPLETELY RULE OUT A STRAY SPRINKLE ACROSS THE HIGHER TERRAIN OF OUR EASTERN VT COUNTIES TODAY, BUT BY AND LARGE DRY WEATHER IS EXPECTED. WINDS NORTH TO NORTHEASTERLY 5 TO 15 MPH, HIGHEST IN THE SLV. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... AS OF 330 AM EDT THURSDAY...MORE OF THE SAME BY TONIGHT THROUGH SATURDAY AS UPPER LOW PRESSURE SLIDES BY TO OUR WEST AND SOUTH AND MEAN PBL FLOW REMAINS GENERALLY LIGHT. WEAK ENERGY SLIDING SOUTHWESTWARD WITHIN THE NORTHEASTERLY MID LEVEL FLOW COULD PRODUCE A STRAY LIGHT SHOWER OR SPRINKLE ACROSS THE SOUTHERN HIGH TERRAIN TONIGHT, OTHERWISE DRY WEATHER SHOULD CONTINUE THROUGH THE PERIOD UNDER VARIABLY CLOUDY/PARTLY CLOUDY SKIES. HIGH TEMPERATURES RANGING THROUGH THE 60S ON FRIDAY, WARMING INTO THE MID 60S TO LOWER 70S BY SATURDAY AS WINDS TREND MORE WESTERLY AND BEGIN TO USHER IN AN AIRMASS MORE CONTINENTAL IN NATURE. DID OPT TO UNDERCUT OVERNIGHT LOWS BY JUST A FEW DEGREES (30S TO LOWER 40S) GIVEN FORECAST OF AT LEAST SOME BREAKS IN THE CLOUD COVER AND RECENT WARM BIAS IN THE BLENDED MOS GUIDANCE. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 235 PM EDT WEDNESDAY...WEATHER TRENDS GOING INTO THE EXTENDED PERIOD CONTINUE TO HIGHLIGHT GENERALLY DRY AND WARM CONDITIONS DOMINATED BY AN UPPER RIDGE FOR THE WEEKEND AND A FAST ZONAL FLOW GOING INTO NEXT WEEK. FORECAST PERIOD BEGINS SATURDAY WHERE AN UPPER LEVEL TROUGH WILL BE EXITING OFF THE ATLANTIC SEABOARD WITH HIGH PRESSURE BUILDING ACROSS MUCH OF THE CENTRAL/SOUTHERN EAST COAST ALONG WITH AND UPPER RIDGE OVER THE NORTHEAST. THIS RIDGE REMAIN GENERALLY IN PLACE FOR THE WEEKEND AND INTO MONDAY OFFERING MOSTLY DRY CONDITIONS. I SAY MOSTLY DRY BECAUSE A SURFACE WARM FRONT WILL PUSH INTO THE NORTHEAST LATE SUNDAY WHICH MAY SPARK A FEW SPRINKLES AND/OR SHOWERS, BUT OVERALL MOISTURE WARM FRONT SHIFTS NORTHEAST OF THE BTV CWA ON MONDAY FULLY ENTRENCHING THE AREA IN THE WARM SECTOR WITH THE WARMEST TEMPS OF THE WEEK EXPECTED BEFORE THE UPPER FLOW TURNS ZONAL AND SOME ENERGY COMING OUT OF THE MIDWEST LOOKS TO RENEW CHANCES FOR SHOWERS TOWARDS MID-WEEK. BEST PART OF THE EXTENDED FORECAST WILL BE A WELCOMED WARMING TREND WITH TEMPS WARMING ABOVE NORMAL FOR THE WEEKEND AND MONDAY. HIGHS WARM INTO THE 60S AREA-WIDE FOR THE WEEKEND AND FURTHER INTO 70S FOR MONDAY, BUT SCALE BACK INTO THE 60S TOWARDS MID-WEEK WITH THE THREAT OF RAIN. LOWS WILL RANGE FROM THE UPPER 30S TO MID 40S SATURDAY NIGHT, BUT WARM INTO 40S AREA-WIDE SUNDAY NIGHT, AND FURTHER INTO THE 50S FOR MONDAY NIGHT. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... THROUGH 06Z FRIDAY...EXPECT PREVAILING VFR THROUGH THE FORECAST PERIOD WITH POSSIBLE MVFR STRATUS AT MPV AND MVFR/IFR GROUND FOG AT SLK. CURRENTLY SKIES CONTINUE TO RANGE FROM CLEAR ACROSS MSS/SLK/BTV TO SOME HIGH CLOUD OVER PBG AND OVC MID-CLOUDS FOR MPV. EXPECT THESE TRENDS TO CONTINUE OVERNIGHT. LATEST GUIDANCE CONTINUES TO POINT TO IDEA OF LOWER STRATUS DECK INTRUDING INTO MPV OVERNIGHT AS LOW- LEVEL FLOW BECOMES EASTERLY, THOUGH CURRENT OBSERVATIONS IN THE GULF OF MAINE AND SOUTHERN NEW ENGLAND SHOW OVC VFR CEILINGS 4000-5000 FEET. AT SLK, PROJECTED LOW TEMPERATURES DROP A FEW DEGREES BELOW CROSSOVER TEMPS IN THE MID- 30S UNDER CLEAR SKIES AND LIGHTENING WINDS, SUPPORTING SOME MVFR TO IFR LIGHT FOG IN LIGHT BL FLOW CONDITIONS. I TRENDED BACK THE TIMING OF THE FOG TO MATCH MORE OF THE RAP SOUNDING. GIVEN WE ARE STILL IN THE PRE GREEN UP PHASE THE ONSET OF LIGHT GROUND FOG WILL LIKELY ONLY OCCUR ONCE WE ARE A FEW DEGREES COLDER THAN THE ACTUAL CROSSOVER TEMP. NORTH/NORTHEAST WINDS BECOME LIGHT/VARIABLE OVERNIGHT. VFR CONDITIONS INTO THURSDAY WITH SCT/BKN CLOUDINESS BETWEEN 5000-7000FT. WINDS GENERALLY NORTH/NORTHEAST 5-8 KTS. OUTLOOK 06Z FRIDAY THROUGH MONDAY... 06Z FRIDAY - 12Z MONDAY...GENERALLY VFR CONDITIONS AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE REGION. SOME MVFR SHOWERS ARE POSSIBLE FRIDAY/SATURDAY AS A COASTAL LOW PASSES WELL OFFSHORE. 12Z MONDAY - 00Z TUESDAY...VFR WITH A CHANCE FOR MVFR SHOWERS AS LOW PRESSURE PASSES NORTH OF THE INTL BORDER. && .EQUIPMENT... AS OF 730 PM EDT TUESDAY...THE TEMPERATURE AND DEW POINT HAS BEEN SPORADICALLY MISSING FROM THE AWOS (AUTOMATED WEATHER OBSERVING SYSTEM) AT RUTLAND (KRUT) SOUTHERN VERMONT REGIONAL AIRPORT. THE FAA AOCC HAS BEEN NOTIFIED OF THIS PROBLEM AND HAVE OPENED A TROUBLE TICKET. THE FAA HAS MAINTENANCE RESPONSIBILITY FOR THE AWOS AT RUTLAND VERMONT. NO ESTIMATE IS AVAILABLE AT THIS TIME AS TO WHEN THE TEMPERATURE AND DEW POINT WILL AGAIN CONSISTENTLY BE REPORTED IN THE KRUT OBSERVATIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...JMG SHORT TERM...JMG LONG TERM...LAHIFF AVIATION...DEAL EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
157 AM EDT THU APR 30 2015 .SYNOPSIS... VARIABLY CLOUDY SKIES AND SEASONABLY MILD TEMPERATURES WILL PERSIST THROUGH THE REST OF THE WEEK AS A LARGE LOW PRESSURE SYSTEM REMAINS WELL OFF THE NORTHEAST UNITED STATES COASTLINE AND ANOTHER SYSTEM PASSES WELL SOUTH OF THE REGION. TEMPERATURES TREND WARMER BY THIS WEEKEND INTO EARLY NEXT WEEK AS SOUTHERLY WINDS RETURN TO THE AREA. OUTSIDE OF A STRAY LIGHT SHOWER ON FRIDAY AND SUNDAY MAINLY DRY WEATHER IS EXPECTED UNTIL TUESDAY WHEN A SURFACE FRONT BRINGS A BETTER CHANCE FOR RAIN. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... AS OF 1009 PM EDT WEDNESDAY...FORECAST REMAINS IN REAL GOOD SHAPE AS CLOUD COVER RANGES FROM CLEAR ACROSS THE ST. LAWRENCE VALLEY AND ADIRONDACKS REGION TO OVERCAST IN CENTRAL AND EASTERN VT. NO MAJOR CHANGES TO THOSE EXPECTATIONS THROUGH THE REST OF THE EVENING. I DID BACK OFF ON MENTION OF PATCHY DRIZZLE IN SOUTHERN VT, HOWEVER. HIGH-RESOLUTION GUIDANCE RH PROGS SUGGESTED POTENTIAL FOR LOWER STRATUS AND POTENTIAL FOR PATCHY DRIZZLE. HOWEVER IT APPEARS THAT GUIDANCE IS OVERDOING LOW-LEVEL MOISTURE, AS METARS IN SOUTHERN NEW ENGLAND INTO NEW HAMPSHIRE SHOW MOSTLY OVERCAST LOW-TO-MID LEVEL CLOUDINESS (4 TO 8 THOUSAND FEET AGL). ASIDE FROM SUBTLE ADJUSTMENTS TO HOURLY TEMPS, DEWPOINTS AND WINDS, REMAINDER OF THE FORECAST IS UNCHANGED. LOOKING AT LOWS LARGELY IN THE 40S, THOUGH CLOSER TO MID 30S IN THE ADIRONDACKS. && .SHORT TERM /8 AM THIS MORNING THROUGH FRIDAY NIGHT/... AS OF 337 PM EDT WEDNESDAY...OVERALL SITUATION REMAINS SIMILAR THURSDAY WITH CLOSED LOW OFFSHORE AND OTHER CLOSED LOW DIVING TO OUR SOUTH AND WEST. MOISTURE STILL EXPECTED TO BE PINWHEELING AROUND...SO EXPECTING VARIABLE PARTLY-MOSTLY CLOUDY SKIES. A HIGHER ELEVATION LIGHT SPRINKLE/SHOWER ALSO CAN`T BE RULED OUT. LOOKING AT HIGHS IN THE 60S FOR MOST LOCATIONS. STRONGER SURGE OF MARINE AIR/BACKDOOR FRONT LOOKS TO ORGANIZE LATER THURSDAY AND PROPAGATE SOUTHWESTWARD ALONG THE SOUTHERN NEW ENGLAND COASTLINE. SOME OF THAT MARINE AIR MAY AGAIN MAKE IT UP INTO PORTIONS OF SOUTHERN VERMONT SO HAVE A SLIGHT CHANCE OF RAIN SHOWERS/PATCHY DRIZZLE IN SOME LOCATIONS. OTHERWISE EXPECT MOSTLY CLOUDY SKIES AND LOWS IN THE UPPER 30S TO MID 40S. BY FRIDAY...THE SECOND UPPER LOW WILL BE DIGGING WELL SOUTH OF THE REGION...HOWEVER THE NORTH COUNTRY WILL STILL BE IN THE LARGE SCALE TROUGH UNDER NORTHERLY FLOW...SO ANOTHER DAY OF VARIABLE CLOUDINESS IS ON TAP ALONG WITH THE POSSIBILITY OF AN ISOLATED INSTABILITY RAIN SHOWER OR TWO...MAINLY HIGHER TERRAIN. HIGHS WILL BE PRETTY MUCH IN THE 60S AREA-WIDE ONCE AGAIN. THE UPPER LOW FINALLY BEGINS TO DEPART ON FRIDAY WITH VARIABLE CLOUDS AND LOWS IN THE 30S/40S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 235 PM EDT WEDNESDAY...WEATHER TRENDS GOING INTO THE EXTENDED PERIOD CONTINUE TO HIGHLIGHT GENERALLY DRY AND WARM CONDITIONS DOMINATED BY AN UPPER RIDGE FOR THE WEEKEND AND A FAST ZONAL FLOW GOING INTO NEXT WEEK. FORECAST PERIOD BEGINS SATURDAY WHERE AN UPPER LEVEL TROUGH WILL BE EXITING OFF THE ATLANTIC SEABOARD WITH HIGH PRESSURE BUILDING ACROSS MUCH OF THE CENTRAL/SOUTHERN EAST COAST ALONG WITH AND UPPER RIDGE OVER THE NORTHEAST. THIS RIDGE REMAIN GENERALLY IN PLACE FOR THE WEEKEND AND INTO MONDAY OFFERING MOSTLY DRY CONDITIONS. I SAY MOSTLY DRY BECAUSE A SURFACE WARM FRONT WILL PUSH INTO THE NORTHEAST LATE SUNDAY WHICH MAY SPARK A FEW SPRINKLES AND/OR SHOWERS, BUT OVERALL MOISTURE WARM FRONT SHIFTS NORTHEAST OF THE BTV CWA ON MONDAY FULLY ENTRENCHING THE AREA IN THE WARM SECTOR WITH THE WARMEST TEMPS OF THE WEEK EXPECTED BEFORE THE UPPER FLOW TURNS ZONAL AND SOME ENERGY COMING OUT OF THE MIDWEST LOOKS TO RENEW CHANCES FOR SHOWERS TOWARDS MID-WEEK. BEST PART OF THE EXTENDED FORECAST WILL BE A WELCOMED WARMING TREND WITH TEMPS WARMING ABOVE NORMAL FOR THE WEEKEND AND MONDAY. HIGHS WARM INTO THE 60S AREA-WIDE FOR THE WEEKEND AND FURTHER INTO 70S FOR MONDAY, BUT SCALE BACK INTO THE 60S TOWARDS MID-WEEK WITH THE THREAT OF RAIN. LOWS WILL RANGE FROM THE UPPER 30S TO MID 40S SATURDAY NIGHT, BUT WARM INTO 40S AREA-WIDE SUNDAY NIGHT, AND FURTHER INTO THE 50S FOR MONDAY NIGHT. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... THROUGH 06Z FRIDAY...EXPECT PREVAILING VFR THROUGH THE FORECAST PERIOD WITH POSSIBLE MVFR STRATUS AT MPV AND MVFR/IFR GROUND FOG AT SLK. CURRENTLY SKIES CONTINUE TO RANGE FROM CLEAR ACROSS MSS/SLK/BTV TO SOME HIGH CLOUD OVER PBG AND OVC MID-CLOUDS FOR MPV. EXPECT THESE TRENDS TO CONTINUE OVERNIGHT. LATEST GUIDANCE CONTINUES TO POINT TO IDEA OF LOWER STRATUS DECK INTRUDING INTO MPV OVERNIGHT AS LOW- LEVEL FLOW BECOMES EASTERLY, THOUGH CURRENT OBSERVATIONS IN THE GULF OF MAINE AND SOUTHERN NEW ENGLAND SHOW OVC VFR CEILINGS 4000-5000 FEET. AT SLK, PROJECTED LOW TEMPERATURES DROP A FEW DEGREES BELOW CROSSOVER TEMPS IN THE MID- 30S UNDER CLEAR SKIES AND LIGHTENING WINDS, SUPPORTING SOME MVFR TO IFR LIGHT FOG IN LIGHT BL FLOW CONDITIONS. I TRENDED BACK THE TIMING OF THE FOG TO MATCH MORE OF THE RAP SOUNDING. GIVEN WE ARE STILL IN THE PRE GREEN UP PHASE THE ONSET OF LIGHT GROUND FOG WILL LIKELY ONLY OCCUR ONCE WE ARE A FEW DEGREES COLDER THAN THE ACTUAL CROSSOVER TEMP. NORTH/NORTHEAST WINDS BECOME LIGHT/VARIABLE OVERNIGHT. VFR CONDITIONS INTO THURSDAY WITH SCT/BKN CLOUDINESS BETWEEN 5000-7000FT. WINDS GENERALLY NORTH/NORTHEAST 5-8 KTS. OUTLOOK 06Z FRIDAY THROUGH MONDAY... 06Z FRIDAY - 12Z MONDAY...GENERALLY VFR CONDITIONS AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE REGION. SOME MVFR SHOWERS ARE POSSIBLE FRIDAY/SATURDAY AS A COASTAL LOW PASSES WELL OFFSHORE. 12Z MONDAY - 00Z TUESDAY...VFR WITH A CHANCE FOR MVFR SHOWERS AS LOW PRESSURE PASSES NORTH OF THE INTL BORDER. && .EQUIPMENT... AS OF 730 PM EDT TUESDAY...THE TEMPERATURE AND DEW POINT HAS BEEN SPORADICALLY MISSING FROM THE AWOS (AUTOMATED WEATHER OBSERVING SYSTEM) AT RUTLAND (KRUT) SOUTHERN VERMONT REGIONAL AIRPORT. THE FAA AOCC HAS BEEN NOTIFIED OF THIS PROBLEM AND HAVE OPENED A TROUBLE TICKET. THE FAA HAS MAINTENANCE RESPONSIBILITY FOR THE AWOS AT RUTLAND VERMONT. NO ESTIMATE IS AVAILABLE AT THIS TIME AS TO WHEN THE TEMPERATURE AND DEW POINT WILL AGAIN CONSISTENTLY BE REPORTED IN THE KRUT OBSERVATIONS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...MUCCILLI NEAR TERM...LOCONTO/MUCCILLI SHORT TERM...MUCCILLI LONG TERM...LAHIFF AVIATION...DEAL EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS RALEIGH NC
802 PM EDT FRI MAY 1 2015 .SYNOPSIS...AN UPPER LEVEL LOW AND ASSOCIATED SURFACE LOW WILL MOVE EAST OF THE AREA TONIGHT...AS HIGH PRESSURE AND MORE SEASONABLE CONDITIONS SPREAD IN FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 320 PM FRIDAY... WATER VAPOR AND LATEST RAP DATA SUGGEST THE UPPER LOW IS NOW OVER THE PAMLICO SOUND AND CONTINUING TO DRIFT EAST...WHILE THE STRONGEST ASSOCIATED VORTICITY IS NOW OVER SOUTHEASTERN NC. MOIST NORTHEASTERLY FLOW...30-35KT AT 850MB...AND ISENTROPIC LIFT OVER THE NORTHERN COASTAL PLAIN HAS GIVEN WAY TO SOME ISENTROPIC DOWNGLIDE THIS AFTERNOON PER RAP ANALYSIS. THE STEEPER LAPSE RATES THAT WERE OVER CENTRAL NC THIS MORNING HAVE ALSO SHIFTED SOUTH/EAST...AND WITH THE LOSS OF BETTER FORCING/LAPSE RATES...SHOWERS HAVE BECOME MORE SCATTERED ACROSS THE NORTHERN PIEDMONT/COASTAL PLAIN OVER THE PAST COUPLE HOURS. THERE ARE SOME ADDITIONAL SMALL DISTURBANCES IN THE CYCLONIC FLOW ALOFT THAT SHOULD AID SHOWER ACTIVITY FOR A FEW MORE HOURS...MOST NOTABLY WITH AN AREA OF SHOWERS MOVING SOUTH THROUGH SOUTHWESTERN VA. THE LATEST HRRR SHOWS THIS CONVECTION REACHING THE TRIAD AROUND 21Z BUT DWINDLING BEFORE MOVING MUCH FURTHER SOUTHEAST AS HEATING...WHAT LITTLE WE HAVE HAD...IS LOST. WILL TREND POPS DOWN FROM WEST TO EAST FOR MOST OF THE AREA...KEEPING A CHANCE POP ACROSS THE WEST THROUGH 00Z. TONIGHT...SKIES WILL BEGIN TO CLEAR WITHIN THE SUBSIDENCE BEHIND THE UPPER LOW...THOUGH GUIDANCE IS IN PRETTY GOOD AGREEMENT ON SOME LINGERING MOISTURE NEAR 5K FT...WHICH SHOULD ALSO DRIFT SOUTHEAST WITH TIME AS THE LOW LEVEL FLOW CONTINUES TO BACK AROUND TO MORE NORTHERLY. A LIGHT WIND WILL CONTINUE OVER THE COASTAL PLAIN...BUT BUT TO THE WEST SOME PATCHY FOG SEEMS POSSIBLE GIVEN LITTLE CHANGE IN AIRMASS AND LIGHT WINDS/DRYING ALOFT. SREF PROBABILITIES FOR FOG ARE NOT VERY HIGH...SO DENSE FOG IS NOT EXPECTED. LOWS IN THE UPPER 40S. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... AS OF 320 PM FRIDAY... ONE LAST RIBBON OF VORTICITY IS EXPECTED TO DROP SOUTH ACROSS THE COASTAL PLAIN AROUND MIDDAY...AND ALL MODELS SHOW A SIGNAL FOR AT LEAST ISOLATED SHOWERS WITH SOME SHALLOW INSTABILITY BEFORE THE ATMOSPHERE DRIES OUT MORE SUBSTANTIALLY AND STRONGER SUBSIDENCE SETS IN. WILL KEEP THE SLIGHT CHANCE POP FROM ROUGHLY ROXBORO TO CLINTON THROUGH MID AFTERNOON. HIGHS 72-76 NORTHEAST TO SOUTHWEST. HIGHS PRESSURE WILL FINALLY BUILD OVERHEAD SATURDAY NIGHT AND SKIES WILL FULLY CLEAR. DESPITE THE GOOD RADIATIONAL COOLING CONDITIONS...THE AIRMASS ACTUALLY MODIFIES SLIGHTLY AND LOWS WILL BE COMPARABLE TO TONIGHT...IF NOT WARMER IN SOME SPOTS WITH UPPER 40S AND LOWER 50S. && .LONG TERM /SUNDAY THROUGH FRIDAY/... AS OF 240 PM FRIDAY... HIGH PRESSURE OVERHEAD ON SUNDAY WILL SLOWLY MIGRATE OFFSHORE BUT CONTINUE TO RIDGE WESTWARD INTO NC THROUGH TUESDAY. A WEAK TROUGH WILL GET SANDWICHED BETWEEN THE EXITING HIGH AND A HIGH OVER THE GREAT LAKES MID-WEEK. ALTHOUGH SOME OF THE MODELS INDICATE A SLIGHT CHANCE FOR SOME SHOWERS IN THE FAR NORTHWEST DURING THE AFTERNOON PERIODS MON-WED...MOST OF THE SHOWER ACTIVITY SHOULD STAY WELL TO THE NORTH AND NORTHWEST. CENTRAL NC WILL REMAIN UNDER HIGH PRESSURE BUT GENERALLY WEAK SURFACE FLOW FOR THE REMAINDER OF THE WEEK. WEDNESDAY THROUGH FRIDAY GETS INTERESTING TO OUR SOUTHEAST AS BOTH THE GFS AND ECMWF GENERATE A TROPICAL LOW PRESSURE SYSTEM OVER THE CARIBBEAN...MOVING SLOWLY NORTH AND STALLING OFF THE CAROLINA COAST. WHILE THERE IS STILL A GOOD DEAL OF UNCERTAINTY WITH THIS SYSTEM GIVEN THAT IT IS FAR OUT IN THE MODEL FORECAST PERIOD...THE FACT THAT BOTH MODELS SHOW SIMILAR FEATURES INCREASES THE CHANCE THAT SOMETHING OF INTEREST WILL DEVELOP OFF THE SOUTHEAST ATLANTIC COAST TOWARD THE END OF THE WEEK. REGARDLESS...ITS EVOLUTION WILL BE SOMETHING TO WATCH. AS FOR TEMPERATURES...STILL EXPECT OUR FIRST EXTENDED PERIOD OF 80 DEGREE DAYS...WITH HIGHS INCREASING ABOUT A DEGREE OR SO A DAY FROM THE MID TO UPPER 70S ON SUNDAY INTO THE LOW TO MID 80S BY FRIDAY. LOWS WILL SEE A SIMILAR TREND...INCREASING FROM THE MID 50S SUNDAY NIGHT INTO THE UPPER 50S TO LOW 60S BY FRIDAY NIGHT. SKIES WILL GENERALLY BE CLEAR TO PARTLY CLOUDY THROUGH MOST OF THE PERIOD...WITH FAIRLY LIGHT WINDS...EXCEPT IN THE SOUTHEAST AS THAT LOW HANGS OFF THE CAROLINA COAST. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... AS OF 800 PM FRIDAY... SHOWER ACTIVITY CONTINUES TO DIMINISH ACROSS THE AREA. VFR CONDITIONS ARE EXPECTED TO PREVAIL DURING THE NEXT 24 HOURS... AS THE UPPER LEVEL LOW PULLS AWAY FROM THE COAST AND SURFACE HIGH PRESSURE BUILDS IN TO THE AREA. THERE IS A CHANCE OF PATCHY FOG OVERNIGHT AS CLOUD COVER CONTINUES TO DIMINISH... BUT CONFIDENCE IS TOO LOW FOR ANY SITE OTHER THAN KRWI TO INCLUDE MENTION AT THIS TIME. OUTLOOK... VFR CONDITIONS ARE LIKELY TO CONTINUE THROUGH THE WEEKEND IN TO EARLY NEXT WEEK AS HIGH PRESSURE MOVES ACROSS THE AREA. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...22 NEAR TERM...22 SHORT TERM...22 LONG TERM...KC AVIATION...30
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
305 PM EDT THU APR 30 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE SLOWLY UP THE CAROLINA COAST THROUGH TONIGHT BEFORE FINALLY MOVING AWAY FROM THE AREA DURING FRIDAY. THE RISK FOR SHOWERS AND SOME THUNDERSTORMS WILL REMAIN THROUGH FRIDAY. HIGH PRESSURE WILL BUILD ACROSS THE AREA FOR THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK. THE DRY WEATHER AND RETURNING SUNSHINE WILL ALLOW TEMPERATURES TO RETURN TO SEASONABLE LEVELS BY THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT.../ AS OF 300 PM THURSDAY...LOW PRESSURE CENTERED SOUTH OF CAPE HATTERAS SHOULD SLOW TONIGHT AS A POWERFUL UPPER LEVEL DISTURBANCE DIVES SOUTHWARD FROM INDIANA INTO NORTH CAROLINA. ALTHOUGH LOW-LEVEL BAROCLINICITY IS VERY WEAK...A FAVORABLY ORIENTED JET STREAK OFFSHORE PLUS INCOMING VORTICITY WITH THE DISTURBANCE SHOULD LEAD TO SLOWLY FALLING PRESSURES OFFSHORE. AWAY FROM EXTREME EASTERN NC (INCLUDING WILMINGTON) THERE HAS BEEN PLENTY OF SUNSHINE TODAY. TEMPERATURES RISING INTO THE 70S PLUS RATHER COOL TEMPERATURES ALOFT HAVE HELPED GENERATE SURFACE-BASED CAPE AS LARGE AS 500 J/KG ALONG AND WEST OF I-95. SO FAR THIS HAS RESULTED IN AN EXPANSIVE CUMULUS FIELD ACROSS WESTERN NC PLUS A SMATTERING OF SHOWERS. AS 800-600 MB TEMPERATURES FALL FURTHER THIS EVENING AND THE FIRST OF SEVERAL UPPER DISTURBANCES ARRIVES FROM THE WEST...THE POTENTIAL FOR SHOWERS WILL EXPAND ACROSS SOUTHEASTERN NORTH CAROLINA AND NORTHERN PORTIONS OF THE PEE DEE REGION. I HAVE DECIDED NOT TO INCLUDE THUNDER IN THE FORECAST AS IT APPEARS AN INVERSION BETWEEN 500-600 MB SHOULD BE SUFFICIENTLY STRONG TO CAP OFF UPDRAFTS BEFORE THEY BECOME COLD ENOUGH ALOFT. 12Z MODELS HAVE BACKED OFF A LITTLE COMPARED TO THEIR 00Z/06Z COUNTERPARTS WITH THE SOUTHERN EXTENT OF PRECIPITATION...AND THIS TREND IS ECHOED BY THE LAST FEW HRRR RUNS AS WELL. BY LATE TONIGHT THE MAIN UPPER LOW WILL WOBBLE INTO CENTRAL NORTH CAROLINA. NEAR AND NORTH OF THE LOW IS WHERE UNSTABLE CONDITIONS SHOULD CONTINUE OVERNIGHT DUE TO COLD AIR ALOFT. OUR FORECAST AREA SHOULD LARGELY REMAIN SOUTH OF THE INSTABILITY...SO ASIDE FROM MAINTAINING 30-40 PERCENT POPS ACROSS LUMBERTON-ELIZABETHTOWN-BURGAW I HAVE CUT POPS TO 10-20 POPS OVERNIGHT...WITH LOWS GENERALLY IN THE LOWER 50S EXCEPT MID 50S AT THE BEACHES. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 PM THURSDAY... A STRONG UPPER LOW WILL CUT BY TO OUR NORTH ON FRIDAY. EVEN SO WE SHOULD SEE VERY STRONG PVA AND HEIGHT FALLS LOCALLY AND SOME LIGHT SHOWERS SEEM LIKELY OVER NORTHERN ZONES. STILL TOUGH TO RULE OUT THUNDER WITH UPWARDS OF 600J/KG OF CAPE DEVELOPING. SOME OF THIS INSTABILITY MAY GO SUFFICIENTLY INTO THE HAIL GROWTH LAYER FOR SOME PEA SIZED HAIL TO REACH THE GROUND UNDERNEATH THE DEEPER CONVECTIVE CELLS. CLOUD COVER WILL MEANWHILE BRING ONE LAST DAY OF CONSIDERABLY COOL TEMPS WITH HIGHS STUCK IN THE 60S. DRY AIR MOVES IN FRIDAY NIGHT INTO SATURDAY. THERE IS HOWEVER ONE TRAILING VORT AND WRAPAROUND MOISTURE ON SATURDAY AND SOME GUIDANCE HINTING AT PRECIP OVER CAPE FEAR/COASTAL NC ZONES. FEEL IF ANYTHING AT ALL WILL BE JUST NON-MEASURABLE AND HAVE KEPT THE FORECAST DRY AT THIS TIME. THE DECREASED CLOUD COVER WILL ALLOW FOR A NICE BUMP IN TEMPERATURES COME SATURDAY BUT THE NORTHERLY FLOW COMPONENT THROUGH A DEEP LAYER WILL STILL KEEP US A TAD BELOW CLIMO. && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 3 PM THURSDAY...BERMUDA HIGH AND MID LEVEL RIDGE BUILDING OVER THE SOUTHEAST WILL KEEP THE REGION DRY DURING THE PERIOD WITH TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO. AS FAR AS THE TROPICAL WAVE/LOW COMBO EMERGING FROM THE BAHAMAS NEXT WEEK GOES THE LATEST MEDIUM RANGE GUIDANCE HAS FALLEN OUT OF FAVOR WITH THIS SCENARIOS. NEARLY ALL OF THE GUIDANCE (INCLUDING THE ENSEMBLES) NOW SHOW A SHEARED OUT SURFACE WAVE MOVING EAST-NORTHEAST...REMAINING WELL SOUTHEAST OF THE COAST. LATER IN THE PERIOD CANNOT RULE OUT AN ISOLATED SEA BREEZE SHOWER AS LOW LEVEL MOISTURE INCREASES BUT COVERAGE WILL BE QUITE LIMITED AND DOES NOT WARRANT INCLUSION OF POP GREATER THAN 15 AT THIS TIME. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AS OF 18Z...CONDITIONS WILL GRADUALLY DETERIORATE TO MVFR/IFR LATER TODAY AND CONTINUE THROUGH MUCH OF THE VALID TAF PERIOD AS LOW CLOUDS...AREAS OF FOG...AND PERIODS OF RAIN MOVE THROUGH THE FORECAST AREA. VFR PREVAILS THIS AFTERNOON WITH LIGHT EAST-NORTHEAST WINDS AND ISOLATED TO SCATTERED SHOWERS AS SEEN FROM LATEST SATELLITE IMAGERY. FOR THIS AFTERNOON AND INTO THE EVENING HOURS...EXPECT RAINFALL TO BECOME MORE WIDESPREAD. CONDITIONS WILL GRADUALLY DETERIORATE TO MVFR/IFR AND CONTINUE INTO SATURDAY AS LOW CIGS AND AREAS OF FOG ADVECT ACROSS THE AREA. EXPECT WINDS TO BACK TO THE NORTHEAST AT ALL SITES THIS AFTERNOON AS LOW PRESSURE MOVES CLOSER TO THE AREA...INCREASING TO AOB 10 KTS...AND POTENTIALLY SLIGHTLY HIGHER ALONG THE COAST. INTO THE OVERNIGHT HOURS...RAIN WILL TAPER OFF BUT ANTICIPATE A RETURN OF -RA/SHRA THURSDAY MORNING. EXTENDED OUTLOOK...A CONTINUING CHANCE FOR SHOWERS WITH POTENTIAL MVFR/IFR CONDITIONS THROUGH FRIDAY. OTHERWISE EXPECT VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM THURSDAY...LOW PRESSURE HAS MOVED SOUTH OF HATTERAS THIS AFTERNOON BUT SHOULD SLOW TONIGHT AS A STRONG UPPER LEVEL DISTURBANCE APPROACHES FROM THE WEST. THIS DISTURBANCE WILL CREATE A ZONE OF WEAKENED PRESSURE GRADIENT ACROSS EASTERN NORTH CAROLINA TONIGHT...WHILE TO THE SOUTH ACROSS SOUTH CAROLINA THE GRADIENT SHOULD GRADUALLY TIGHTEN WITH INCREASING WESTERLY WINDS EXPECTED. BY DAYBREAK WINDS JUST EAST OF WINYAH BAY/GEORGETOWN COULD REACH 15-20 KT. THE VARIOUS COMPUTER MODELS HAVE DIFFERING POSITIONS OF WHERE THE BOUNDARY BETWEEN THESE STRONGER WEST WINDS AND LIGHTER NORTH WINDS CLOSER TO THE LOW WILL SET UP...AND I HAVE FOLLOWED THE 12Z GFS AS A GUIDE TONIGHT. SEAS CURRENTLY RANGE FROM 2-3 FEET INSIDE 20 MILES OF SHORE...TO 4 FEET OUT AT THE FRYING PAN SHOALS BUOY. SEAS MAY SUBSIDE A BIT THIS EVENING BUT SHOULD INCREASE AGAIN OVERNIGHT...ESPECIALLY SOUTH OF CAPE FEAR...DUE TO THE INCREASING WIND SPEEDS. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 PM THURSDAY...LOW PRESSURE OFF CAPE HATTERAS WILL BE SLOW TO MOVE ON FRIDAY, ENERGIZED IN PART BY A STRONG LOW IN THE MID LEVELS. THIS FEATURE WILL STRENGTHEN VERTICAL MIXING MORE THAN THE ACTUAL SURFACE PRESSURE GRADIENT, POSSIBLY ENOUGH FOR SOME ADVISORY-WORTHY 25KT WINDS OVER MAINLY JUST OUR NORTHERNMOST ZONE-MAINLY FRIDAY NIGHT. ALL MODELS ARE NOT CONVINCED OF THIS AND THERE IS STILL A BIT OF TIME TO IRON OUT THE UNCERTAINTY SO ONE WILL NOT BE RAISED AT THIS TIME. THE LOW WILL BE GRADUALLY PULLING AWAY TO THE NORTHEAST ON SATURDAY. WINDS LOCALLY WILL REMAIN N TO NW AND SLOWLY SUBSIDE. THERE MAY EVEN BE A BIT OF BACKSWELL FROM THE OFFSHORE STORM AS IT GROWS A BIT LARGER IN SIZE. LONG TERM /SUNDAY THROUGH TUESDAY/... AS OF 3 PM THURSDAY...SURFACE HIGH MOVING OFF THE COAST SUN MORNING WILL SETUP NEAR BERMUDA SUN EVENING AND REMAIN IN PLACE THROUGH THE END OF THE PERIOD. LIGHT AND VARIABLE WINDS ON SUN...WITH SEA BREEZE DOMINATING NEAR SHORE FLOW...WILL BECOME SOUTHEAST TO SOUTH MON AND TUE. GRADIENT WILL REMAIN ON THE WEAK SIDE WITH SPEEDS GENERALLY 10 KT OR LESS. DAILY SEA BREEZE WILL RESULT IN A SLIGHT BUMP IN SPEEDS NEAR SHORE IN THE AFTERNOON. SEAS AROUND 2 FT WILL BE MAINTAINED THROUGH THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...TRA SHORT TERM...MBB LONG TERM...III AVIATION...SGL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EDT THU APR 30 2015 .SYNOPSIS...LOW PRESSURE WILL LINGER OVER AND JUST OFF THE NORTH CAROLINA COAST THROUGH FRIDAY. A STRONG UPPER LEVEL DISTURBANCE WILL APPROACH THE AREA FROM THE NORTHWEST TODAY... THEN SHIFT OVERHEAD TONIGHT THROUGH FRIDAY. THE LOW AND DISTURBANCE WILL MOVE OFFSHORE LATE FRIDAY NIGHT... AND HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. && .NEAR TERM /TODAY THROUGH FRIDAY NIGHT/... AS OF 340 AM THURSDAY... OUR WEATHER FOR THE NEXT 36-48 HOURS WILL BE DRIVEN BY TWO PRIMARY FEATURES... A SHORTWAVE TROUGH CROSSING SRN AL/GA THIS MORNING THEN MOVING OFFSHORE BY AFTERNOON... AND A POTENT MID LEVEL LOW OVER LOWER MI THIS MORNING THAT WILL CROSS NC LATE TONIGHT THROUGH FRI. BOTH OF THESE WILL BE OPERATING ON A SOMEWHAT MOIST COLUMN WITH SLIGHTLY ABOVE NORMAL PW AND COOLING TEMPS ALOFT... LEADING TO UNSETTLED WEATHER FOR CENTRAL NC. FOR THIS MORNING... AREAS OF LIGHT RAIN AND DRIZZLE PERSIST OVER AND EAST OF THE TRIANGLE... A FUNCTION OF ENHANCED ATLANTIC EASTERLY INFLOW AND MOIST ISENTROPIC UPGLIDE AROUND 295K NEAR AND NE OF THE 850 MB LOW OVER SE NC. THIS LOW WILL MOVE SLOWLY NE OVER ERN NC TODAY... AS THE ABOVE-NORMAL PW SHIFTS SLOWLY EAST TO COASTAL SECTIONS... AND ACCORDINGLY THE MOIST UPGLIDE WILL TRANSLATE NE INTO ERN VA LATER TODAY. WE`LL RETAIN A GOOD CHANCE OF RAIN IN THE EAST FOR MUCH OF THE MORNING... GRADUALLY SHIFTING EAST OF THE AREA BY THE NOON HOUR. MEANWHILE... THE WRN CWA WILL SEE A BRIEF LULL IN PRECIP CHANCES THIS MORNING... BENEATH LOWER PW... DOWNSLOPE 850 MB FLOW... AND NEUTRAL VERTICAL MOTION BEHIND THE DEPARTING WAVE ALOFT. THE LATEST HRRR RUNS SUPPORT PATCHES OF FOG THROUGH DAYBREAK IN THE SW CWA... WHERE SKIES FIRST CLEARED OUT EARLIER THIS MORNING. FOR THIS AFTERNOON... THE RELATIVE MINIMUM IN RAIN CHANCES FOR MOST OF CENTRAL NC WILL BE SHORT LIVED... AS THE MI LOW DROPS SSE TOWARD THE WEST SLOPES OF THE SRN APPALACHIANS... WITH WEAK BUT PERSISTENT MID LEVEL HEIGHT FALLS STRETCHING ACROSS NC. MID LEVEL LAPSE RATES OF 6.5-7.0 C/KM SPREAD INTO WRN/CENTRAL NC FROM THE NW DURING THE DAY... PUSHING MUCAPE VALUES UP TO 250-750 J/KG... WITH ADDED FORCING FOR ASCENT FROM MID LEVEL DPVA AND PERSISTENT UPPER DIVERGENCE. THE HI-RES WRF ARW/NMM AS WELL AS RECENT HRRR RUNS SHOW SHOWERS DEVELOPING OVER THE WRN PIEDMONT EARLY THIS AFTERNOON (RIGHT ON THE HEELS OF THE RAIN THAT WILL BE PUSHING OUT OF THE FAR NE CWA BY THIS TIME)... AND THE FORECAST WILL FOLLOW THESE TRENDS WITH POPS RAMPING UP TO GOOD CHANCE AND LOW-END LIKELY ESPECIALLY ACROSS THE NORTH THIS AFTERNOON... STARTING FIRST OVER THE NW CWA AND SPREADING ESE. DON`T EXPECT ANY SEVERE WEATHER... BUT GIVEN THESE STEEP LAPSE RATES AND INVERTED-V SIGNALS ON FORECAST SOUNDINGS LATE TODAY... LOCALLY STRONGER WIND GUSTS AND A LITTLE SMALL HAIL ARE NOT OUT OF THE QUESTION. EXPECT HIGHS FROM THE MID 60S NE WHERE SKIES WILL STAY MOSTLY CLOUDY... TO THE LOWER 70S IN THE SW CWA WHERE SUNSHINE WILL BE MOST ABUNDANT THROUGH THE FIRST HALF OF THE DAY. FOR TONIGHT THROUGH FRI NIGHT: THE MID LEVEL LOW IS EXPECTED TO DIVE FROM ERN KY ESE THROUGH WRN NC TONIGHT... AND THE SCATTERED TO NUMEROUS SHOWERS AND PERHAPS A FEW STORMS OVER THE PIEDMONT AND INTO THE SANDHILLS EARLY THIS EVENING WILL ACCORDINGLY SPREAD EAST. COVERAGE SHOULD DECREASE A BIT WITH THE NOCTURNAL COOLING TRIMMING INSTABILITY SOMEWHAT... BUT THE MID LEVEL LAPSE RATES WILL REMAIN AROUND 6.5 OVER THE NRN CWA OVERNIGHT... WITH PERSISTENT LOW LEVEL MASS CONVERGENCE ALONG THE SHARPENING LOW LEVEL TROUGH AXIS ACROSS NC... ALONG WITH PERSISTENT UPPER DIVERGENCE. PW WILL STAY ELEVATED ESPECIALLY ACROSS THE NE HALF OF THE FORECAST AREA. WILL KEEP CHANCE POPS OVERNIGHT INTO FRI... HIGHEST OVER THE NRN AND ERN CWA. LOWS 48- 53. SHOWERS SHOULD SLOWLY DECREASE AND EXIT TO THE EAST AS THE LOW TO MID LEVEL LOW DEPARTS TO OUR EAST DURING FRI. WILL KEEP CHANCE POPS ESPECIALLY NORTH AND EAST THROUGH EARLY AFTERNOON... THEN DECREASE CHANCES FROM MID AFTERNOON ONWARD. WITH CONSIDERABLE CLOUDS FOR MOST OF THE DAY AND MODEL THICKNESSES RUNNING 20 M OR SO BELOW NORMAL... EXPECT COOL HIGHS FROM THE LOWER 60S NE TO UPPER 60S SW. WE SHOULD SEE CLEARING SKIES FRI NIGHT AS THE COLUMN DRIES OUT WITHIN POST-LOW SUBSIDENCE. LOWS AROUND 45-50. -GIH && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 245 AM THURSDAY... CERTAINLY A DRYING TREND FOR THE WEEKEND AS SURFACE HIGH PRESSURE MOVES IN FROM THE WEST WITH NORTHWEST FLOW ALOFT. WINDS WILL BE LIGHT SO ANY COLD AIR ADVECTION ASSOCIATED WITH THE FRONT SIDE OF THE HIGH WILL BE LIMITED AND PARTLY CLOUDY SKIES FOR MUCH OF THE DAY SHOULD ALLOW FOR DAYTIME HEATING TO BRING MAX TEMPERATURE UP INTO THE LOW TO MID 70S FOR MUCH OF THE AREA. LATER IN THE AFTERNOON...MODELS ARE TRYING TO PICK UP A SURFACE TROUGH EXTENDING FROM A LOW PRESSURE CENTERED OVER QUEBEC. THE BEST VORTICITY ASSOCIATED WITH THIS FEATURE IS BETWEEN 900-800 MB AND THE MODEL PRODUCES SOME BROKEN CEILINGS WITH A FEW LIGHT SHOWERS ACROSS THE EASTERN HALF OF THE CWA. QPF IS VERY MINIMAL AND CONFIDENCE IS LOW THAT THERE WOULD BE ENOUGH FORCING OR MOISTURE TO PRODUCE ANY RAIN. MORE LIKELY WILL SEE AN INCREASE IN CLOUDS BUT SUBSIDENCE FROM THE APPROACHING HIGH WILL LIKELY OVERCOME MOST OF WHAT THE SURFACE TROUGH HAS TO OFFER. WILL CARRY SLIGHT CHANCE POPS SATURDAY AFTERNOON IN THE NORTHEAST BUT OTHERWISE DRY. THIS FEATURE WILL MOVE OFF TO THE EAST SATURDAY NIGHT AND SKIES WILL BE MOSTLY CLEAR WITH LOWS IN THE LOWER 50S. SUNDAY THE HIGH PRESSURE SYSTEM MOVES OVER THE AREA AND OFF TO THE EAST BY LATE AFTERNOON/EVENING. WARM MOIST AIR ADVECTION COULD BRING SOME BROKEN CUMULUS TO THE AREA BY THE AFTERNOON BUT MOISTURE IS LIMITED AND OTHER THAN A STRAY SHOWER OR TWO EXPECT DRY CONDITIONS. WITH SOUTHWESTERLY RETURN FLOW OVER THE AREA (ALTHOUGH VERY LIGHT) EXPECT HIGHS TO MOVE UP INTO THE UPPER 70S. LOWS IN THE MID 50S. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 245 AM THURSDAY... THE HIGH WILL REMAIN IN PLACE FOR THE FIRST HALF OF THE WORK WEEK AND A SIMILAR PATTERN WILL RESULT IN MOSTLY DRY WEATHER WITH WARM TEMPERATURES...WITH HIGHS NEAR 80 DEGREES. A STATIONARY FRONT DRAPED ACROSS THE MID-ATLANTIC MAY THREATEN NORTHERN COUNTIES WITH A FEW CLOUDS BUT OTHERWISE NOT MUCH IMPACT TO WEATHER. THE GFS HINTS AT THIS FEATURE TRYING TO PUSH DOWN INTO THE AREA ON WEDNESDAY BUT THE ECMWF KEEPS THE FEATURE OVER THE DC AREA. THEREFORE CONFIDENCE IS LOW ENOUGH IN THE PLACEMENT OF THIS FEATURE TO KEEP THE FORECAST DRY AND PARTLY CLOUDY THROUGH WEDNESDAY. LOWS DURING THIS TIMEFRAME IN THE UPPER 50S TO NEAR 60 DEGREES. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 650 AM THURSDAY... WITH THE EXCEPTION OF FAY... WHICH WILL SEE A PERIOD OF MVFR CIGS UNTIL AROUND 15Z THIS MORNING... EASTERN TAFS INCLUDING RDU/RWI SHOULD SEE VFR CONDITIONS THROUGH 18Z THIS AFTERNOON... WITH ANY CIGS HOLDING ABOVE 4000 FT AGL... HOWEVER PERIODS OF PATCHY LIGHT RAIN AT THESE SITES THIS MORNING THROUGH EARLY AFTERNOON MAY PRODUCE BRIEF BORDERLINE MVFR VSBYS (5SM-6SM). AT INT/GSO... A PERIOD OF MVFR FOG IS EXPECTED EARLY THIS MORNING (MAINLY UNTIL 13Z)... ALTHOUGH OTHERWISE VFR CONDITIONS WILL DOMINATE FROM MID MORNING THROUGH 18Z WITH A LOWER CHANCE OF RAIN AS COMPARED TO EASTERN SITES. AFTER 18Z... AN APPROACHING STRONG UPPER LOW FROM THE NW WILL BRING A GOOD CHANCE OF SHOWERS AND ISOLATED STORMS... FIRST AT INT/GSO/RDU/RWI THEN AT FAY AFTER 21Z. SUB-VFR CIGS/VSBYS WILL INITIALLY BE BRIEF WITH THESE SHOWERS BEFORE 00Z. AFTER 00Z... IFR FOG/STRATUS IS EXPECTED TO FORM AT RDU/RWI/FAY... WHILE VFR CIGS SHOULD HOLD AT INT/GSO THROUGH THE END OF THE TAF VALID PERIOD (06Z FRI). GOOD CHANCE OF SUB-VFR CONDITIONS (MAINLY IFR) AS WE APPROACH DAYBREAK FRI... ESPECIALLY AT RDU/RWI... AS A STRONG UPPER LEVEL DISTURBANCE SHIFTS OVER THE AREA. WINDS WILL BE LIGHT (UNDER 8 KTS) AND VARIABLE... EXCEPT 15Z-22Z WHEN WINDS WILL BE AROUND 8 KTS AND MAINLY FROM THE NW AT INT/GSO/FAY AND MAINLY FROM THE NORTH AT RDU/RWI. LOOKING BEYOND 12Z EARLY FRI MORNING: CIGS ARE EXPECTED TO SLOWLY RISE TO MVFR BY 16Z-18Z AND TO VFR BY 21Z FRI AS THE DISTURBANCE EXITS. VFR CONDITIONS THEN LIKELY FRI NIGHT THROUGH MON AS HIGH PRESSURE BUILDS OVER THE REGION. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...ELLIS LONG TERM...ELLIS AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
340 AM EDT THU APR 30 2015 .SYNOPSIS...LOW PRESSURE WILL LINGER OVER AND JUST OFF THE NORTH CAROLINA COAST THROUGH FRIDAY. A STRONG UPPER LEVEL DISTURBANCE WILL APPROACH THE AREA FROM THE NORTHWEST TODAY... THEN SHIFT OVERHEAD TONIGHT THROUGH FRIDAY. THE LOW AND DISTURBANCE WILL MOVE OFFSHORE LATE FRIDAY NIGHT... AND HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. && .NEAR TERM /TODAY THROUGH FRIDAY NIGHT/... AS OF 340 AM THURSDAY... OUR WEATHER FOR THE NEXT 36-48 HOURS WILL BE DRIVEN BY TWO PRIMARY FEATURES... A SHORTWAVE TROUGH CROSSING SRN AL/GA THIS MORNING THEN MOVING OFFSHORE BY AFTERNOON... AND A POTENT MID LEVEL LOW OVER LOWER MI THIS MORNING THAT WILL CROSS NC LATE TONIGHT THROUGH FRI. BOTH OF THESE WILL BE OPERATING ON A SOMEWHAT MOIST COLUMN WITH SLIGHTLY ABOVE NORMAL PW AND COOLING TEMPS ALOFT... LEADING TO UNSETTLED WEATHER FOR CENTRAL NC. FOR THIS MORNING... AREAS OF LIGHT RAIN AND DRIZZLE PERSIST OVER AND EAST OF THE TRIANGLE... A FUNCTION OF ENHANCED ATLANTIC EASTERLY INFLOW AND MOIST ISENTROPIC UPGLIDE AROUND 295K NEAR AND NE OF THE 850 MB LOW OVER SE NC. THIS LOW WILL MOVE SLOWLY NE OVER ERN NC TODAY... AS THE ABOVE-NORMAL PW SHIFTS SLOWLY EAST TO COASTAL SECTIONS... AND ACCORDINGLY THE MOIST UPGLIDE WILL TRANSLATE NE INTO ERN VA LATER TODAY. WE`LL RETAIN A GOOD CHANCE OF RAIN IN THE EAST FOR MUCH OF THE MORNING... GRADUALLY SHIFTING EAST OF THE AREA BY THE NOON HOUR. MEANWHILE... THE WRN CWA WILL SEE A BRIEF LULL IN PRECIP CHANCES THIS MORNING... BENEATH LOWER PW... DOWNSLOPE 850 MB FLOW... AND NEUTRAL VERTICAL MOTION BEHIND THE DEPARTING WAVE ALOFT. THE LATEST HRRR RUNS SUPPORT PATCHES OF FOG THROUGH DAYBREAK IN THE SW CWA... WHERE SKIES FIRST CLEARED OUT EARLIER THIS MORNING. FOR THIS AFTERNOON... THE RELATIVE MINIMUM IN RAIN CHANCES FOR MOST OF CENTRAL NC WILL BE SHORT LIVED... AS THE MI LOW DROPS SSE TOWARD THE WEST SLOPES OF THE SRN APPALACHIANS... WITH WEAK BUT PERSISTENT MID LEVEL HEIGHT FALLS STRETCHING ACROSS NC. MID LEVEL LAPSE RATES OF 6.5-7.0 C/KM SPREAD INTO WRN/CENTRAL NC FROM THE NW DURING THE DAY... PUSHING MUCAPE VALUES UP TO 250-750 J/KG... WITH ADDED FORCING FOR ASCENT FROM MID LEVEL DPVA AND PERSISTENT UPPER DIVERGENCE. THE HI-RES WRF ARW/NMM AS WELL AS RECENT HRRR RUNS SHOW SHOWERS DEVELOPING OVER THE WRN PIEDMONT EARLY THIS AFTERNOON (RIGHT ON THE HEELS OF THE RAIN THAT WILL BE PUSHING OUT OF THE FAR NE CWA BY THIS TIME)... AND THE FORECAST WILL FOLLOW THESE TRENDS WITH POPS RAMPING UP TO GOOD CHANCE AND LOW-END LIKELY ESPECIALLY ACROSS THE NORTH THIS AFTERNOON... STARTING FIRST OVER THE NW CWA AND SPREADING ESE. DON`T EXPECT ANY SEVERE WEATHER... BUT GIVEN THESE STEEP LAPSE RATES AND INVERTED-V SIGNALS ON FORECAST SOUNDINGS LATE TODAY... LOCALLY STRONGER WIND GUSTS AND A LITTLE SMALL HAIL ARE NOT OUT OF THE QUESTION. EXPECT HIGHS FROM THE MID 60S NE WHERE SKIES WILL STAY MOSTLY CLOUDY... TO THE LOWER 70S IN THE SW CWA WHERE SUNSHINE WILL BE MOST ABUNDANT THROUGH THE FIRST HALF OF THE DAY. FOR TONIGHT THROUGH FRI NIGHT: THE MID LEVEL LOW IS EXPECTED TO DIVE FROM ERN KY ESE THROUGH WRN NC TONIGHT... AND THE SCATTERED TO NUMEROUS SHOWERS AND PERHAPS A FEW STORMS OVER THE PIEDMONT AND INTO THE SANDHILLS EARLY THIS EVENING WILL ACCORDINGLY SPREAD EAST. COVERAGE SHOULD DECREASE A BIT WITH THE NOCTURNAL COOLING TRIMMING INSTABILITY SOMEWHAT... BUT THE MID LEVEL LAPSE RATES WILL REMAIN AROUND 6.5 OVER THE NRN CWA OVERNIGHT... WITH PERSISTENT LOW LEVEL MASS CONVERGENCE ALONG THE SHARPENING LOW LEVEL TROUGH AXIS ACROSS NC... ALONG WITH PERSISTENT UPPER DIVERGENCE. PW WILL STAY ELEVATED ESPECIALLY ACROSS THE NE HALF OF THE FORECAST AREA. WILL KEEP CHANCE POPS OVERNIGHT INTO FRI... HIGHEST OVER THE NRN AND ERN CWA. LOWS 48- 53. SHOWERS SHOULD SLOWLY DECREASE AND EXIT TO THE EAST AS THE LOW TO MID LEVEL LOW DEPARTS TO OUR EAST DURING FRI. WILL KEEP CHANCE POPS ESPECIALLY NORTH AND EAST THROUGH EARLY AFTERNOON... THEN DECREASE CHANCES FROM MID AFTERNOON ONWARD. WITH CONSIDERABLE CLOUDS FOR MOST OF THE DAY AND MODEL THICKNESSES RUNNING 20 M OR SO BELOW NORMAL... EXPECT COOL HIGHS FROM THE LOWER 60S NE TO UPPER 60S SW. WE SHOULD SEE CLEARING SKIES FRI NIGHT AS THE COLUMN DRIES OUT WITHIN POST-LOW SUBSIDENCE. LOWS AROUND 45-50. -GIH && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 245 AM THURSDAY... CERTAINLY A DRYING TREND FOR THE WEEKEND AS SURFACE HIGH PRESSURE MOVES IN FROM THE WEST WITH NORTHWEST FLOW ALOFT. WINDS WILL BE LIGHT SO ANY COLD AIR ADVECTION ASSOCIATED WITH THE FRONT SIDE OF THE HIGH WILL BE LIMITED AND PARTLY CLOUDY SKIES FOR MUCH OF THE DAY SHOULD ALLOW FOR DAYTIME HEATING TO BRING MAX TEMPERATURE UP INTO THE LOW TO MID 70S FOR MUCH OF THE AREA. LATER IN THE AFTERNOON...MODELS ARE TRYING TO PICK UP A SURFACE TROUGH EXTENDING FROM A LOW PRESSURE CENTERED OVER QUEBEC. THE BEST VORTICITY ASSOCIATED WITH THIS FEATURE IS BETWEEN 900-800 MB AND THE MODEL PRODUCES SOME BROKEN CEILINGS WITH A FEW LIGHT SHOWERS ACROSS THE EASTERN HALF OF THE CWA. QPF IS VERY MINIMAL AND CONFIDENCE IS LOW THAT THERE WOULD BE ENOUGH FORCING OR MOISTURE TO PRODUCE ANY RAIN. MORE LIKELY WILL SEE AN INCREASE IN CLOUDS BUT SUBSIDENCE FROM THE APPROACHING HIGH WILL LIKELY OVERCOME MOST OF WHAT THE SURFACE TROUGH HAS TO OFFER. WILL CARRY SLIGHT CHANCE POPS SATURDAY AFTERNOON IN THE NORTHEAST BUT OTHERWISE DRY. THIS FEATURE WILL MOVE OFF TO THE EAST SATURDAY NIGHT AND SKIES WILL BE MOSTLY CLEAR WITH LOWS IN THE LOWER 50S. SUNDAY THE HIGH PRESSURE SYSTEM MOVES OVER THE AREA AND OFF TO THE EAST BY LATE AFTERNOON/EVENING. WARM MOIST AIR ADVECTION COULD BRING SOME BROKEN CUMULUS TO THE AREA BY THE AFTERNOON BUT MOISTURE IS LIMITED AND OTHER THAN A STRAY SHOWER OR TWO EXPECT DRY CONDITIONS. WITH SOUTHWESTERLY RETURN FLOW OVER THE AREA (ALTHOUGH VERY LIGHT) EXPECT HIGHS TO MOVE UP INTO THE UPPER 70S. LOWS IN THE MID 50S. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 245 AM THURSDAY... THE HIGH WILL REMAIN IN PLACE FOR THE FIRST HALF OF THE WORK WEEK AND A SIMILAR PATTERN WILL RESULT IN MOSTLY DRY WEATHER WITH WARM TEMPERATURES...WITH HIGHS NEAR 80 DEGREES. A STATIONARY FRONT DRAPED ACROSS THE MID-ATLANTIC MAY THREATEN NORTHERN COUNTIES WITH A FEW CLOUDS BUT OTHERWISE NOT MUCH IMPACT TO WEATHER. THE GFS HINTS AT THIS FEATURE TRYING TO PUSH DOWN INTO THE AREA ON WEDNESDAY BUT THE ECMWF KEEPS THE FEATURE OVER THE DC AREA. THEREFORE CONFIDENCE IS LOW ENOUGH IN THE PLACEMENT OF THIS FEATURE TO KEEP THE FORECAST DRY AND PARTLY CLOUDY THROUGH WEDNESDAY. LOWS DURING THIS TIMEFRAME IN THE UPPER 50S TO NEAR 60 DEGREES. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 115 AM THURSDAY... EASTERN TAFS INCLUDING RDU/RWI/FAY SHOULD SEE VFR CONDITIONS PERSIST THROUGH 18Z THIS AFTERNOON... WITH ANY CIGS HOLDING ABOVE 4000 FT AGL... HOWEVER PERIODS OF PATCHY LIGHT RAIN AT THESE SITES THIS MORNING THROUGH EARLY AFTERNOON MAY PRODUCE BRIEF BORDERLINE MVFR VSBYS (5SM-6SM). AT INT/GSO... A PERIOD OF IFR/LIFR FOG IS EXPECTED EARLY THIS MORNING (MAINLY 06Z-12Z)... ALTHOUGH OTHERWISE VFR CONDITIONS WILL DOMINATE FROM MID MORNING THROUGH 18Z WITH A LOWER CHANCE OF RAIN AS COMPARED TO EASTERN SITES. AFTER 18Z... AN APPROACHING STRONG UPPER LOW FROM THE NW WILL BRING A GOOD CHANCE OF SHOWERS AND ISOLATED STORMS... FIRST AT INT/GSO/RDU/RWI THEN AT FAY AFTER 21Z. SUB-VFR CIGS/VSBYS WILL INITIALLY BE BRIEF WITH THESE SHOWERS BEFORE 00Z. AFTER 00Z... IFR FOG/STRATUS IS EXPECTED TO FORM AT RDU/RWI/FAY... WHILE VFR CIGS SHOULD HOLD AT INT/GSO THROUGH THE END OF THE TAF VALID PERIOD (06Z FRI). WINDS WILL BE LIGHT (UNDER 8 KTS) AND VARIABLE EXCEPT 15Z-21Z WHEN WINDS WILL BE AROUND 8 KTS AND MAINLY FROM THE NW AT INT/GSO/FAY AND MAINLY FROM THE NORTH AT RDU/RWI. LOOKING BEYOND 06Z EARLY FRI MORNING: GOOD CHANCE OF SUB-VFR CONDITIONS (MAINLY IFR) AS WE APPROACH DAYBREAK FRI... AS A STRONG UPPER LEVEL DISTURBANCE SHIFTS OVER THE AREA. CIGS ARE EXPECTED TO SLOWLY RISE TO MVFR BY 16Z-18Z AND TO VFR BY 21Z FRI AS THE DISTURBANCE EXITS. VFR CONDITIONS THEN LIKELY FRI NIGHT THROUGH MON AS HIGH PRESSURE BUILDS OVER THE REGION. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...ELLIS LONG TERM...ELLIS AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1227 AM CDT THU APR 30 2015 .UPDATE... ISSUED AT 1221 AM CDT THU APR 30 2015 NO MAJOR CHANGES TO THE FORECAST THIS EVENING. UPDATED NEAR TERM FORECAST TO MATCH OBSERVATION TRENDS. UPDATE ISSUED AT 935 PM CDT WED APR 29 2015 GIVEN STEEP MID LEVEL RATES ALONG AND AHEAD OF THE COLD FRONT ACROSS EASTERN MONTANA...AND SPORADIC LIGHTNING STRIKES ASSOCIATED WITH THE ONGOING PRECIPITATION...ADDED AN ISOLATED THUNDER MENTION ACROSS THE WEST LATE TONIGHT INTO THURSDAY MORNING. UPDATE ISSUED AT 551 PM CDT WED APR 29 2015 NO SIGNIFICANT CHANGES WITH THIS UPDATE OTHER THAN TO EXPAND THE ISOLATED SHOWER MENTION ACROSS THE WEST LATE TONIGHT GIVEN TRENDS IN THE 19-21 UTC HRRR ITERATIONS WHICH PROPAGATE SHOWERS ALONG THE COLD FRONT ACROSS THE MONTANA BORDER AROUND 10 UTC. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 317 PM CDT WED APR 29 2015 CURRENTLY...SUNNY SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA. AS UPPER LEVEL RIDGING MOVES INTO WESTERN AND CENTRAL NORTH DAKOTA. CURRENT TEMPERATURES ARE IN THE UPPER 60S TO LOWER 70S STATEWIDE. SURFACE HIGH PRESSURE WAS LOCATED OVER THE EASTERN DAKOTA AND MINNESOTA WITH DEVELOPING LOW PRESSURE IN THE LEE OF THE CANADIAN AND NORTHERN ROCKIES. TONIGHT...EXPECT MAINLY CLEAR SKIES...BUT SHOULD SEE INCREASING CLOUDS WEST TOWARD MORNING AS THE MID-UPPER LEVEL RIDGE PUSHES INTO MINNESOTA AND SOUTHWEST FLOW ALOFT BRINGS INCREASING MID LEVEL MOISTURE INTO THE WEST. A SHORTWAVE TRACKING ACROSS THE NORTHERN ROCKIES IS SITUATED OVER NORTH CENTRAL MONTANA WITH AN ASSOCIATED SURFACE COLD FRONT OVER WESTERN NORTH DAKOTA. INCREASING 850MB WINDS AHEAD OF THE FRONT WITH THERMAL RIDGING MOVING INTO THE AREA SHOULD KEEP OVERNIGHT LOWS MILD WITH READINGS GENERALLY IN THE 40S. THURSDAY...THE UPPER LEVEL TROUGH MOVES INTO EASTERN MONTANA AROUND MIDDAY AND INTO WESTERN NORTH DAKOTA BY EARLY EVENING. THIS WILL PUSH THE COLD FRONT TO NEAR THE HIGHWAY 83 CORRIDOR BY MIDDAY. AHEAD OF THE COLD FRONT WARM SOUTH TO SOUTHWEST WINDS SHOULD BUMP TEMPERATURES INTO THE LOW TO MIDDLE 70S. THE DRY SOUTHWEST FLOW SHOULD ALLOW DEWPOINT TEMPERATURES TO FALL TO THE LOW TO MID 30S SOUTH CENTRAL...AND INTO THE LOWER 30S OVER THE JAMES RIVER VALLEY. AS WE MIX OUT IN THE AFTERNOON...WE SEE THE POTENTIAL FOR SUSTAINED WINDS AROUND 20 MPH WITH GUSTS TO AROUND 30 MPH OVER THE JAMES RIVER VALLEY...TAPERING SLIGHTLY AS YOU GO WEST TO THE MISSOURI RIVER VALLEY. THIS PRODUCE AFTERNOON HUMIDITIES FROM THE UPPER TEENS IN THE SOUTHERN JAMES RIVER VALLEY...TO THE MID TO UPPER 20S ALONG THE MISSOURI RIVER. WILL BE ISSUING A RED FLAG WARNING DUE TO THE LOW HUMIDITIES AND STRONG WINDS THURSDAY AFTERNOON INTO THE EARLY EVENING. NORTHWEST WINDS BEHIND THE COLD FRONT WILL BRING IN COOLER AIR...RAISING HUMIDITIES AND BRINGING A CHANCE OF SHOWERS. INSTABILITY IS LIMITED BUT DID MENTION AN ISOLATE THUNDERSTORM THURSDAY AFTERNOON. CRITICAL FIRE WEATHER ISSUES ARE EXPECTED TO DIMINISH WITH THE PASSAGE OF THE COLD FRONT. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 317 PM CDT WED APR 29 2015 AS AN UPPER LEVEL TROUGH...LOCATED OVER SASKATCHEWAN AND EASTERN NORTH DAKOTA...CONTINUES EASTWARD ACROSS THE NORTHERN PLAINS...CHANCES FOR RAIN WILL PERSIST IN CENTRAL AND EASTERN AREAS OF THE STATE THROUGH THURSDAY NIGHT. THEREAFTER...THE CURRENT ENSEMBLE AND DETERMINISTIC MODELS PROVIDE AGREEMENT ON ZONAL FLOW BECOMING DOMINANT THE THROUGH PERIOD. SEVERAL EMBEDDED UNPREDICTABLE SHORTWAVES ARE PROJECTED WITHIN THE UPPER LEVEL FLOW...CREATING FREQUENT CHANCES FOR RAIN AND THE POSSIBILITY FOR THUNDERSTORMS. THIS WEEKEND LOOKS TO BE THE BEST CHANCES FOR WIDESPREAD RAIN WITH THUNDERSTORMS MOSTLY CONFINED TO SOUTHERN AREAS OF THE STATE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1221 AM CDT THU APR 30 2015 A COLD FRONT WILL ENTER WESTERN NORTH DAKOTA EARLY THURSDAY MORNING AND MOVE INTO CENTRAL NORTH DAKOTA BY THE AFTERNOON. SCATTERED SHOWERS AND AN ISOLATED THUNDERSTORM OR TWO ARE EXPECTED ALONG THE FRONT. SOUTHERLY WINDS GUSTING NEAR 30 KTS AHEAD OF THE FRONT WILL BECOME WESTERLY BEHIND THE FRONT. VFR CONDITIONS EXPECTED OUTSIDE OF SHOWERS AND THUNDERSTORMS. && .BIS WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR NDZ023-025-036-037-046>048-050-051. && $$ UPDATE...AJ SHORT TERM...AC LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1049 PM EDT FRI MAY 1 2015 .SYNOPSIS... A WEAK SURFACE TROUGH WILL REMAIN OVER EASTERN PENNSYLVANIA INTO TONIGHT. HIGH PRESSURE WILL THEN DRIFT SLOWLY FROM THE TENNESSEE VALLEY TO THE EAST COAST BY THE END OF THE WEEKEND...LEADING TO WARMER TEMPERATURES THAT WILL CONTINUE THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... REGIONAL RADAR LOOP AT 03Z SHOWS SHOWERS HAVE DWINDLED ALONG SFC TROF AND PLUME OF HIGHER PWATS ACROSS THE SUSQ VALLEY. BASED ON RADAR TRENDS AND LATEST HRRR OUTPUT...HAVE REMOVED MENTION OF PRECIP FOR THE REST OF THE NIGHT. IR IMAGERY SHOWS CLEARING SKIES ALREADY WORKING INTO THE NW MTNS AS OF 03Z...AND EXPECT THIS CLEARING TREND TO PUSH SE OVERNIGHT. THE CLOUDS WILL REMAIN MOST PERSISTENT IN THE HIGHER PWAT AIR EAST OF THE TROF ACROSS THE SE COUNTIES. CLEARING SKY...LGT WIND AND DRIER AIR SHOULD ALLOW TEMPS TO FALL INTO THE U30S ACROSS THE NW MTNS BY DAWN...WHILE THE L/M40S EXPECTED ELSEWHERE. SOME PATCHY FOG MAY FORM OVERNIGHT ACROSS THE SUSQ VALLEY...WHERE LOW LVL MOISTURE WILL REMAIN THE HIGHEST EAST OF SFC TROF. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... SATURDAY LOOKS EVEN DRIER AND CERTAINLY MILDER THAN TODAY...WITH SOME DIURNAL CU POPPING UP. ISOLD DIURNAL CONVECTION EXPECTED AGAIN IN VICINITY OF WEAK SFC TROUGH...WHICH WILL LIE ACROSS SE PA. WILL CARRY SCHC OF A PM -SHRA FROM HARRISBURG SOUTH AND EASTWARD. ENS MEAN 8H TEMPS SHOULD TRANSLATE TO MAX TEMPS FROM THE U60S OVR THE HIGH TERRAIN...TO THE L70S IN THE VALLEYS. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... A HIGH PRESSURE SYSTEM WILL RESIDE OVER THE REGION THROUGH THE SECOND HALF OF THE WEEKEND AND THROUGH MONDAY. AS THE RIDGE MOVES EASTWARD A WEAK ZONAL FLOW MOVES OVER THE REGION OUT AHEAD OF AN APPROACHING BOUNDARY THAT WILL LAY ACROSS PENNSYLVANIA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY IS ALONG THE SOUTHERN END OF AN UPPER LEVEL TROUGH THAT WILL BE MOVING THROUGH EASTERN CANADA. MID TO LOW LEVEL MOISTURE SHOULD ALLOW FOR SHOWERS THROUGH THIS TIMEFRAME. HAVE INCREASED POPS AND ADJUSTED TIMING OF POSSIBLE THUNDER. ESPECIALLY AS THIS PATTERN COULD ALLOW FOR UPSTREAM FORMING OF CONVECTION THAT GETS FUNNELED EASTWARD IN THE WESTERLY FLOW ALONG THE TOP OF THE UPPER RIDGE. THESE SHOWERS AND THUNDERSTORMS COULD CONTINUE TUESDAY NIGHT. EXPECT A CHANCE FOR THE SYSTEM TO WEAKEN...BUT SHOWERS TO REMAIN POSSIBLE THROUGH WEDNESDAY INTO WEDNESDAY NIGHT. THE REGION SHOULD THEN DRY OUT AS A NEGATIVELY TILTED RIDGE BUILDS OVER THE MIDWEST THROUGH THE SECOND HALF OF NEXT WEEK. THIS RIDGE SHOULD KEEP ANY PRECIPITATION AT BAY INTO FRIDAY...THOUGH THE LONG RANGE MODELS BEGIN TO VARY IN SOLUTION...ESPECIALLY TIMING AND STRENGTH. THE GEFS ENSEMBLES DON/T HAVE A CLEAR SIGNAL AT THIS POINT FOR THE SECOND HALF OF NEXT WEEK. DUE TO THE VARIABILITY IN THE EXTENDED FORECAST HAVE KEPT ONLY A MENTION OF SHOWERS IN THE FORECAST FOR THE SECOND HALF OF NEXT WEEK...BUT OVERALL IT SHOULD BE QUITE MILD WITH MUCH OF THE TIME BEING RAIN FREE. THE WARMING TREND WILL CONTINUE AS TEMPERATURES SHOULD BE ABOVE NORMAL THROUGH NEXT WEEK. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... DIURNAL SHOWERS BEGINNING TO WANE AS THE SUN SETS. THERE WAS ENOUGH SHOWER COVERAGE TO WARRANT THE MENTION OF BR IN THE OVERNIGHT PERIOD...SIMILAR TO LAST NIGHT. DID NOT BRING ANY PARTICULAR AIRFIELD BELOW VFR BUT DID MENTION A SLIGHT REDUCTION IN VIS/CIGS AT MOST SITES. HIGH PRESSURE THEN MOVES IN FROM THE WEST THROUGH MONDAY WITH MAINLY VFR CONDITIONS. THERE COULD STILL BE SOME ISOLD POP UPS FOR THE AFTN ON SAT AND PERHAPS SUNDAY - BUT MAINLY MORE TO THE EAST OF THE AREA. APPROACHING FRONT MAY TRIGGER SOME SHOWERS IN THE NORTH ON TUESDAY. OUTLOOK... SAT-MON...GENERALLY VFR. TUE...VFR...WITH SHRA IN THE NORTH. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...FITZGERALD SHORT TERM...DANGELO/FITZGERALD LONG TERM...LA CORTE/CERU AVIATION...TYBURSKI
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
922 PM EDT FRI MAY 1 2015 .SYNOPSIS... A WEAK SURFACE TROUGH WILL REMAIN OVER PENNSYLVANIA INTO TONIGHT. HIGH PRESSURE WILL THEN DRIFT SLOWLY FROM THE TENNESSEE VALLEY TO THE EAST COAST BY THE END OF THE WEEKEND...LEADING TO WARMER TEMPERATURES THAT WILL CONTINUE THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... REGIONAL RADAR LOOP AT 01Z SHOWING ONLY A FEW ISOLD LEFT ALONG SFC TROF AND PLUME OF HIGHER PWATS RUNNING FROM ARND KBGM SOUTH THRU ARND KHGR. SHORTWAVE SEEN ENTERING NW PA AT 01Z IN WV LOOP WILL PUSH THIS BOUNDARY AND REMAINING CHC OF AN ISOLD -SHRA SE OVERNIGHT. BASED ON RADAR TRENDS AND LATEST HRRR OUTPUT...WILL ONLY CARRY MENTION OF A -SHRA OVR THE EASTERN ZONES THRU MIDNIGHT...AFTER WHICH THE CHC OF MEASURABLE PRECIP SHOULD FALL BLW 10 PCT. IR IMAGERY SHOWS CLEARING SKIES ALREADY WORKING INTO THE NW MTNS AS OF 01Z...AND EXPECT THIS CLEARING TREND TO PUSH SE OVERNIGHT. THE CLOUDS WILL REMAIN MOST PERSISTENT IN THE HIGHER PWAT AIR EAST OF THE TROF ACROSS THE SE COUNTIES. CLEARING SKY...LGT WIND AND DRIER AIR SHOULD ALLOW TEMPS TO FALL INTO THE U30S ACROSS THE NW MTNS BY DAWN...WHILE THE L/M40S EXPECTED ELSEWHERE. SOME PATCHY FOG MAY FORM OVERNIGHT ACROSS THE SUSQ VALLEY...WHERE LOW LVL MOISTURE WILL REMAIN THE HIGHEST EAST OF SFC TROF. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... SATURDAY LOOKS EVEN DRIER AND CERTAINLY MILDER THAN TODAY...WITH SOME DIURNAL CU POPPING UP. ISOLD DIURNAL CONVECTION EXPECTED AGAIN IN VICINITY OF WEAK SFC TROUGH...WHICH WILL LIE ACROSS SE PA. WILL CARRY SCHC OF A PM -SHRA FROM HARRISBURG SOUTH AND EASTWARD. ENS MEAN 8H TEMPS SHOULD TRANSLATE TO MAX TEMPS FROM THE U60S OVR THE HIGH TERRAIN...TO THE L70S IN THE VALLEYS. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... A HIGH PRESSURE SYSTEM WILL RESIDE OVER THE REGION THROUGH THE SECOND HALF OF THE WEEKEND AND THROUGH MONDAY. AS THE RIDGE MOVES EASTWARD A WEAK ZONAL FLOW MOVES OVER THE REGION OUT AHEAD OF AN APPROACHING BOUNDARY THAT WILL LAY ACROSS PENNSYLVANIA MONDAY NIGHT INTO TUESDAY. THIS BOUNDARY IS ALONG THE SOUTHERN END OF AN UPPER LEVEL TROUGH THAT WILL BE MOVING THROUGH EASTERN CANADA. MID TO LOW LEVEL MOISTURE SHOULD ALLOW FOR SHOWERS THROUGH THIS TIMEFRAME. HAVE INCREASED POPS AND ADJUSTED TIMING OF POSSIBLE THUNDER. ESPECIALLY AS THIS PATTERN COULD ALLOW FOR UPSTREAM FORMING OF CONVECTION THAT GETS FUNNELED EASTWARD IN THE WESTERLY FLOW ALONG THE TOP OF THE UPPER RIDGE. THESE SHOWERS AND THUNDERSTORMS COULD CONTINUE TUESDAY NIGHT. EXPECT A CHANCE FOR THE SYSTEM TO WEAKEN...BUT SHOWERS TO REMAIN POSSIBLE THROUGH WEDNESDAY INTO WEDNESDAY NIGHT. THE REGION SHOULD THEN DRY OUT AS A NEGATIVELY TILTED RIDGE BUILDS OVER THE MIDWEST THROUGH THE SECOND HALF OF NEXT WEEK. THIS RIDGE SHOULD KEEP ANY PRECIPITATION AT BAY INTO FRIDAY...THOUGH THE LONG RANGE MODELS BEGIN TO VARY IN SOLUTION...ESPECIALLY TIMING AND STRENGTH. THE GEFS ENSEMBLES DON/T HAVE A CLEAR SIGNAL AT THIS POINT FOR THE SECOND HALF OF NEXT WEEK. DUE TO THE VARIABILITY IN THE EXTENDED FORECAST HAVE KEPT ONLY A MENTION OF SHOWERS IN THE FORECAST FOR THE SECOND HALF OF NEXT WEEK...BUT OVERALL IT SHOULD BE QUITE MILD WITH MUCH OF THE TIME BEING RAIN FREE. THE WARMING TREND WILL CONTINUE AS TEMPERATURES SHOULD BE ABOVE NORMAL THROUGH NEXT WEEK. && .AVIATION /01Z SATURDAY THROUGH WEDNESDAY/... DIURNAL SHOWERS BEGINNING TO WANE AS THE SUN SETS. THERE WAS ENOUGH SHOWER COVERAGE TO WARRANT THE MENTION OF BR IN THE OVERNIGHT PERIOD...SIMILAR TO LAST NIGHT. DID NOT BRING ANY PARTICULAR AIRFIELD BELOW VFR BUT DID MENTION A SLIGHT REDUCTION IN VIS/CIGS AT MOST SITES. HIGH PRESSURE THEN MOVES IN FROM THE WEST THROUGH MONDAY WITH MAINLY VFR CONDITIONS. THERE COULD STILL BE SOME ISOLD POP UPS FOR THE AFTN ON SAT AND PERHAPS SUNDAY - BUT MAINLY MORE TO THE EAST OF THE AREA. APPROACHING FRONT MAY TRIGGER SOME SHOWERS IN THE NORTH ON TUESDAY. OUTLOOK... SAT-MON...GENERALLY VFR. TUE...VFR...WITH SHRA IN THE NORTH. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...FITZGERALD SHORT TERM...DANGELO/FITZGERALD LONG TERM...LA CORTE/CERU AVIATION...TYBURSKI
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
318 AM EDT THU APR 30 2015 .SYNOPSIS... AN UPPER LOW WILL DROP SLOWLY ACROSS THE AREA THURSDAY AND FRIDAY. HIGH PRESSURE WILL THEN DRIFT SLOWLY FROM THE TENNESSEE VALLEY TO THE EAST COAST AND OVER BERMUDA. THE TEMPERATURES SHOULD WARM AND WEATHER STAY FAIR SATURDAY INTO THE NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 1030 PM UPDATE... MINOR CHANGES MADE TO SEVERAL WEATHER ELEMENTS FOR THE OVERNIGHT PERIOD. LATEST HRRR AND WRF ARW MODELS SUGGEST THAT MOST /OR ALL/ OF THE NIGHT WILL BE DRY ACROSS CENTRAL AND ERN PARTS OF THE CWA. SHOWERS WILL BE SLOWLY DEVELOPING AND DRIFTING NORTH ACROSS THE WRN MTNS...AS A RESULT OF A LLVL INVERTED TROUGH /NEAR THE PA/OH BORDER AT 0230Z/ DRIFTING A BIT MORE TO THE EAST...AND BEING OVERRUN BY THE LEADING EDGE OF SOME MID LAYER COOLING AND INCREASED UPPER LEVEL DIVERGENCE. QPF THROUGH 12Z IS LESS THAN ONE-TENTH OF AN INCH WHERE IT DOES RAIN ACROSS THE WRN MTNS. ELSEWHERE...ZEROES IN THE RAINFALL DEPT WILL CONTINUE TO SUFFICE. EARLY EVENING DISCUSSION... MAINLY SCATTERED...FLAT HIGH-BASED CU ARE MELTING AWAY WITH THE SETTING SUN IN MANY LOCATIONS. A BKN LAYER OF CLOUDS AT THIS SAME LEVEL COVERING PORTIONS OF THE NW MTNS SHOULD SLOWLY EXPAND SOUTH AND EAST ACROSS THE CWA OVERNIGHT AS PWATS INCREASE BY ABOUT 0.25 OF AN INCH AND LARGE SCALE UPPER LEVEL DIVERGENCE/LIFT INCREASES AHEAD OF A WEAK CLOSED LOW AT 500 MB. SKY COVER MAY BE SKEWED MORE TWD SKC THAN BKN OVER THE NEXT 3-5 HOURS ACRS MUCH OF CENTRAL PENN. WINDS WILL BE VERY LIGHT FOR THE MOST PART AND VEER BY ABOUT 40-50 DEG THROUGH THE NIGHT /FROM NORTH TO NORTHEAST/. A WEAK NERLY UPSLOPE FLOW AT LOW LEVELS WILL COMBINE WITH THE INCREASING DYNAMIC LIFT FROM THE APPROACHING UPPER LOW...TO EXPAND THE CLOUD COVER IN THE 7-10 KFT AGL LAYER...AND TRIGGER SOME SHOWERS ACROSS THE LAURELS LATER THIS EVENING. THE SHOWERS WILL INCREASE IN AREAL COVERAGE LATE TONIGHT AND EARLY THURSDAY. MIN TEMPS EARLY THURSDAY WILL VARY FROM THE UPPER 30S AND LOWER 40S ACROSS THE NORTH...AND MID TO UPPER 40S IN THE SOUTH. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/... SHOWERS OVER THE LAURELS/WRN MTS WILL SPREAD OUT A BIT...ADVANCING TO THE EAST AND NORTH THROUGH THE MORNING AS THE UPPER HEIGHTS GET LOWEST OVERHEAD IN THE AFTERNOON/EVENING. BUT THE COLDEST OF THE AIR WILL PASS TO OUR SOUTH. THE INSTABILITY AND SLOW MOVING NATURE OF THESE SHOWERS COULD PRODUCE SOME HEAVY RAIN. QPF GETS CLOSE TO AN INCH BY THE END OF THE DAY OVER THE SW...WITH A HALF AN INCH OR SO UP TO STATE COLLEGE AND HARRISBURG. CAPES REMAIN BELOW 500 IN GENERAL AND LI/S SCRAPE -1...SO A MENTION OF THUNDER IS WARRANTED BUT ALSO NOT ENTIRELY NECESSARY. MAXES SHOULD BE BACK NEAR 70 OR EVEN L70S IN THE EAST WHERE A P/S SKY IN THE MORNING SHOULD HELP TEMPS RISE. THE CLOUDS SHOULD KEEP EVERYONE ELSE IN THE U50S TO M60S. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... LINGERING COLD TEMPS ALOFT...COMBINED WITH WEAK SHORTWAVES DIVING INTO BASE OF UPPER TROUGH OVR PA...SHOULD PROMOTE SCT DIURNAL SHOWERS FRI AND SAT. PLENTY OF CU/SC EXPECTED BENEATH UPPER TROF WITH HIGHS ONLY IN THE U50S/L60S FRIDAY...THEN BRIGHTER/MILDER WX LIKELY SAT...AS HEIGHTS BEGIN TO RISE OVR THE NORTHEAST CONUS. HIGH CONFIDENCE IN A WARMING TREND SUN-TUE...AS ALL MED RANGE GUIDANCE SHOWS A BUILDING RIDGE ACROSS THE NORTHEAST CONUS. AS SFC HIGH PUSHES OFF THE E COAST...RETURN SW FLOW WILL ADVECT INCREASINGLY WARM AIR INTO PA. GEFS AND ECENS MEAN 8H TEMPS RISE TO BTWN 10-12C BY EARLY NEXT WEEK...IMPLYING WIDESPREAD 70S FOR HIGHS AND SOME 80S IN THE S VALLEYS. ECENS TRACKS A WEAK NORTHERN STREAM SHORTWAVE ACROSS ONTARIO/QUEBEC EARLY NEXT WEEK. WILL INTRODUCE AN INCREASING CHC OF SHRA/TSRA LATE MON/TUE...AS ASSOC DYING COLD FRONT PUSHES SOUTHWARD FROM NY STATE. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... LOW PRESSURE OVER MICHIGAN EARLY THIS MORNING WILL DIVE SOUTHEAST TO WEST VIRGINIA BY THIS EVENING. THIS SYSTEM WILL BRING SHOWERS TO THE WESTERN HALF OF THE STATE TODAY. HOWEVER...SIG CIG/VIS REDUCTIONS ARE NOT ANTICIPATED. BIGGEST THREAT TO AVIATION DURING THE DAYLIGHT HRS WILL COME BTWN 18Z-00Z...WHEN A FEW TSRA COULD DEVELOP OVR THE CENTRAL PART OF THE STATE...GENERALLY WEST OF KMDT AND KIPT. A BRIEF VIS REDUCTION IS POSSIBLE FROM THESE STORMS. HOWEVER...WILL NOT CARRY EXPLICIT MENTION OF TSRA IN FCST ATTM...AS ANY REDUCTIONS WOULD BE BRIEF AND IMPOSSIBLE TO TIME THIS FAR OUT. SHRA/TSRA SHOULD DIMINISH AFTER DARK...AS LOW PRESSURE SYSTEM PASSES SOUTH OF THE STATE. HOWEVER...MOIST EASTERLY FLOW ASCENDING THE LAUREL HIGHLANDS COULD POTENTIALLY RESULT IFR CIGS AT KJST AFTER 23Z. OUTLOOK... FRI...AM LOW CIGS POSSIBLE KJST/KAOO. SAT-MON...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO/LAMBERT NEAR TERM...LAMBERT SHORT TERM...DANGELO LONG TERM...FITZGERALD/GARTNER AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1209 AM EDT THU APR 30 2015 .SYNOPSIS... AN UPPER LOW WILL DROP SLOWLY ACROSS THE AREA THURSDAY AND FRIDAY. HIGH PRESSURE WILL THEN DRIFT SLOWLY FROM THE TENNESSEE VALLEY TO THE EAST COAST AND OVER BERMUDA. THE TEMPERATURES SHOULD WARM AND WEATHER STAY FAIR SATURDAY INTO THE NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 1030 PM UPDATE... MINOR CHANGES MADE TO SEVERAL WEATHER ELEMENTS FOR THE OVERNIGHT PERIOD. LATEST HRRR AND WRF ARW MODELS SUGGEST THAT MOST /OR ALL/ OF THE NIGHT WILL BE DRY ACROSS CENTRAL AND ERN PARTS OF THE CWA. SHOWERS WILL BE SLOWLY DEVELOPING AND DRIFTING NORTH ACROSS THE WRN MTNS...AS A RESULT OF A LLVL INVERTED TROUGH /NEAR THE PA/OH BORDER AT 0230Z/ DRIFTING A BIT MORE TO THE EAST...AND BEING OVERRUN BY THE LEADING EDGE OF SOME MID LAYER COOLING AND INCREASED UPPER LEVEL DIVERGENCE. QPF THROUGH 12Z IS LESS THAN ONE-TENTH OF AN INCH WHERE IT DOES RAIN ACROSS THE WRN MTNS. ELSEWHERE...ZEROES IN THE RAINFALL DEPT WILL CONTINUE TO SUFFICE. EARLY EVENING DISCUSSION... MAINLY SCATTERED...FLAT HIGH-BASED CU ARE MELTING AWAY WITH THE SETTING SUN IN MANY LOCATIONS. A BKN LAYER OF CLOUDS AT THIS SAME LEVEL COVERING PORTIONS OF THE NW MTNS SHOULD SLOWLY EXPAND SOUTH AND EAST ACROSS THE CWA OVERNIGHT AS PWATS INCREASE BY ABOUT 0.25 OF AN INCH AND LARGE SCALE UPPER LEVEL DIVERGENCE/LIFT INCREASES AHEAD OF A WEAK CLOSED LOW AT 500 MB. SKY COVER MAY BE SKEWED MORE TWD SKC THAN BKN OVER THE NEXT 3-5 HOURS ACRS MUCH OF CENTRAL PENN. WINDS WILL BE VERY LIGHT FOR THE MOST PART AND VEER BY ABOUT 40-50 DEG THROUGH THE NIGHT /FROM NORTH TO NORTHEAST/. A WEAK NERLY UPSLOPE FLOW AT LOW LEVELS WILL COMBINE WITH THE INCREASING DYNAMIC LIFT FROM THE APPROACHING UPPER LOW...TO EXPAND THE CLOUD COVER IN THE 7-10 KFT AGL LAYER...AND TRIGGER SOME SHOWERS ACROSS THE LAURELS LATER THIS EVENING. THE SHOWERS WILL INCREASE IN AREAL COVERAGE LATE TONIGHT AND EARLY THURSDAY. MIN TEMPS EARLY THURSDAY WILL VARY FROM THE UPPER 30S AND LOWER 40S ACROSS THE NORTH...AND MID TO UPPER 40S IN THE SOUTH. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... SHOWERS OVER THE LAURELS/WRN MTS WILL SPREAD OUT A BIT...ADVANCING TO THE EAST AND NORTH THROUGH THE MORNING AS THE UPPER HEIGHTS GET LOWEST OVERHEAD IN THE AFTERNOON/EVENING. BUT THE COLDEST OF THE AIR WILL PASS TO OUR SOUTH. THE INSTABILITY AND SLOW MOVING NATURE OF THESE SHOWERS COULD PRODUCE SOME HEAVY RAIN. QPF GETS CLOSE TO AN INCH BY THE END OF THE DAY OVER THE SW...WITH A HALF AN INCH OR SO UP TO STATE COLLEGE AND HARRISBURG. CAPES REMAIN BELOW 500 IN GENERAL AND LI/S SCRAPE -1...SO A MENTION OF THUNDER IS WARRANTED BUT ALSO NOT ENTIRELY NECESSARY. MAXES SHOULD BE BACK NEAR 70 OR EVEN L70S IN THE EAST WHERE A P/S SKY IN THE MORNING SHOULD HELP TEMPS RISE. THE CLOUDS SHOULD KEEP EVERYONE ELSE IN THE U50S TO M60S. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... LINGERING COLD TEMPS ALOFT...COMBINED WITH WEAK SHORTWAVES DIVING INTO BASE OF UPPER TROUGH OVR PA...SHOULD PROMOTE SCT DIURNAL SHOWERS FRI AND SAT. PLENTY OF CU/SC EXPECTED BENEATH UPPER TROF WITH HIGHS ONLY IN THE U50S/L60S FRIDAY...THEN BRIGHTER/MILDER WX LIKELY SAT...AS HEIGHTS BEGIN TO RISE OVR THE NORTHEAST CONUS. HIGH CONFIDENCE IN A WARMING TREND SUN-TUE...AS ALL MED RANGE GUIDANCE SHOWS A BUILDING RIDGE ACROSS THE NORTHEAST CONUS. AS SFC HIGH PUSHES OFF THE E COAST...RETURN SW FLOW WILL ADVECT INCREASINGLY WARM AIR INTO PA. GEFS AND ECENS MEAN 8H TEMPS RISE TO BTWN 10-12C BY EARLY NEXT WEEK...IMPLYING WIDESPREAD 70S FOR HIGHS AND SOME 80S IN THE S VALLEYS. ECENS TRACKS A WEAK NORTHERN STREAM SHORTWAVE ACROSS ONTARIO/QUEBEC EARLY NEXT WEEK. WILL INTRODUCE AN INCREASING CHC OF SHRA/TSRA LATE MON/TUE...AS ASSOC DYING COLD FRONT PUSHES SOUTHWARD FROM NY STATE. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... LATEST SHORT RANGE MODELS DELAY THE RAIN AS IT CORRESPONDS TO THE DRY LOW LEVELS. THE LOW LEVELS WILL SLOWLY MOISTENS THROUGH THE OVERNIGHT PERIOD. AS AN UPPER LEVEL LOW DROPS SOUTH THROUGH MICHIGAN AND DOWN THROUGH THE SOUTH...THE FLOW WILL SHIFT TO THE SOUTH AND COUPLED WITH MOISTENING LLVL FLOW WILL COMBINE TO CREATE SOME INSTABILITY THROUGH THE NIGHT AND EXPAND IN THE HEATING OF THE DAY TOMORROW. VFR WILL CONTINUE THROUGH MOST OF THE EVENING...SLOWLY DECREASING IN CIGS AND VSBYS BEGINNING AT JST AND CREEPING TO THE NORTH AND THEN EASTWARD WITH MVFR CONDITIONS THE MAIN CONCERN IN RAIN SHOWERS AND LOWERING CIGS. AS THE SHRA SPREADS TO THE N/E THROUGH THE LATE NIGHT AND EARLY MORNING AND KBFD AND KAOO MAY HAVE SHOWERS BEFORE SUNRISE. SOME POSSIBLE OF THUNDER EXISTS AFTER 18Z THURSDAY...MAINLY IN THE SRN TERMINALS. IPT WILL REMAIN ABOVE MVFR BEFORE LATE TOMORROW AFTERNOON...WHEN THE SHOWERS WILL OVERSPREAD THE REGION. MDT AND LNS WILL REMAIN VFR BEFORE MVFR CIGS IN SHOWERS ARRIVE LATE TOMORROW AFTERNOON. OUTLOOK... FRI...LOW VFR/MVFR IN SCATTERED RAIN SHOWERS. SAT-MON...VFR BUT WITH SCATTERED DIURNAL SHOWERS POSSIBLE...MAINLY OVER THE MTNS && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO/LAMBERT NEAR TERM...LAMBERT SHORT TERM...DANGELO LONG TERM...FITZGERALD/GARTNER AVIATION...DANGELO/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
438 PM EDT THU APR 30 2015 .SYNOPSIS... AS A LOW PRESSURE SYSTEM GRADUALLY MOVES OFFSHORE TONIGHT AND TOMORROW...DRIER AIR WILL OVERSPREAD THE REGION AND REMAIN IN PLACE THROUGH EARLY NEXT WEEK. THIS PATTERN WILL BE SLOW TO CHANGE AND WILL FAVOR MOSTLY DRY AND MILD CONDITIONS THROUGH MID WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 425 PM...THE FIRST REAL BAND OF SHOWERS ASSOCIATED WITH UPPER LOW/COLD POOL AND NW FLOW IS PROGRESSING ACROSS THE NC MTNS ATTM. IT/S NOT ABUNDANTLY CLEAR HOW THIS ACTIVITY WILL RESPOND TO THE ONGOING DOWNSLOPE FLOW EAST OF THE BLUE RIDGE...SO WHILE POPS HAVE BEEN INCREASED ACROSS THE NC FOOTHILLS...THEY HAVE BEEN MAINTAINED IN THE 50-60 PERCENT RANGE. THE PRIMARY ADJUSTMENT TO THE FORECAST FOR THE REMAINDER OF THE AFTERNOON HAS BEEN TO TEMPER THE THUNDER MENTION...AS COVERAGE OF DEEPER CONVECTION HAS BEEN ISOLATED AT BEST THUS FAR...AND IS UNLIKELY TO CHANGE BASED UPON THE RATHER SHALLOW NATURE OF BUOYANCY PROFILES. WE WILL GENERALLY MENTION SCATTERED TS ACROSS THE MTNS...AND ISOLATED TO THE EAST. HAVING SAID THAT...THERE WILL PROBABLY BE QUITE A BIT OF SMALL HAIL THIS AFTERNOON...AS FREEZING LEVELS ARE BELOW 10 KFT...AND WILL ONLY FALL MORE AS THE UPPER LOW DRAWS NEARER. SOME GUSTY WINDS WILL ALSO LIKELY BE SEEN IN LIGHT OF LOW LEVEL LAPSE RATES GREATER THEN 9 C/KM AND SURFACE DEWPOINT DEPRESSIONS OF AROUND 30 DEGREES. AS OF 225 PM EDT THU...A CLOSED 500 MB LOW SPINNING OVER THE OHIO VALLEY WILL MOVE SE ACROSS THE APPALACHIANS TONIGHT. AHEAD OF THIS SYSTEM...REGIONAL RADAR COVERAGE HAS INCREASED FROM SE KY TO THE SRN APPALACHIANS. THE LATEST HRRR MODEL RUNS INDICATE SEVERAL ROUNDS OF SCATTERED CONVECTION CROSSING THE REGION THROUGH THE EVENING HOURS...IMPACTING LOCATIONS FARTHER S WITH TIME AS A COLD FRONT PUSHES THROUGH THE AREA. STEEP MID LEVEL LAPSE RATES AROUND 7 DEG C/KM OR BETTER WILL TRAVERSE THE AREA WITH THE UPPER COLD POCKET...ESPECIALLY THE INTERSTATE 40 CORRIDOR. IN ADDITION... FREEZING LEVELS AT OR BELOW 8 KFT WILL CONTRIBUTE TO SMALL HAIL POTENTIAL WITH ANY BETTER CONVECTIVE ELEMENTS. SHEAR COULD BE A BIT BETTER IN SRN SECTIONS THIS EVENING...BUT THE WIND DOES NOT APPEAR TO POSE MUCH THREAT GIVEN THE LIMITED DCAPE AND SHALLOW TOPS. THE HWO MENTION ADVERTISING SMALL HAIL WITH ANY THUNDER WILL BE MAINTAINED. THE COLD CORE LOW WILL PASS OVERHEAD TONIGHT...WITH SOME MEASURE OF NW FLOW MOISTURE PERSISTING ALONG THE SPINE OF THE SRN APPALACHIANS INTO FRI MORNING. CONTINUED MTN SHOWERS FROM STEEP LAPSE RATES WILL BE THE MAIN CONCERN. ALTHOUGH 850 MB TEMPS SHOULD STAY JUST ABOVE FREEZING...ANY BETTER SHOWER RATES COULD BRING SNOW LEVELS DOWN INTO THE HIGHER TERRAIN. ANY SNOW ACCUMS SHOULD BE LIGHT AND CONFINED TO THE RIDGE TOPS...BUT FLURRIES/RIME/GRAUPEL UNDER ANY HEAVIER SHOWERS CANNOT BE RULED OUT DOWN INTO THE MTN VALLEYS. ALSO CANNOT RULE OUT ISOLD ADVECTIVE FREEZE ACROSS THE HIGHEST PEAKS OVERNIGHT...BUT NO WARNING PRODUCT SHOULD BE NEEDED. THE CLOSED H5 LOW SHOULD MOVE OFF TO THE EAST FRI MORNING...WITH DEEP LAYER NRLY FLOW IN PLACE ACROSS THE FORECAST AREA. MOISTURE IN THE NRLY FLOW WILL AFFECT MAINLY THE FOOTHILLS AND PIEDMONT OF WRN NC FRI. FAIRLY STEEP LAPSE RATES WILL KEEP THE SHOWER POTENTIAL GOING THROUGH FRI. WILL FEATURE MAXES A BIT BELOW GUIDANCE CONSENSUS GIVEN THE COLD AIR STRATOCUMULUS SKY COVER. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... AS OF 200 PM THU...CLOSED UPPER LOW WILL MOVE FURTHER OUT OVER THE ATLANTIC FRI NIGHT INTO SAT...AND AS HEIGHTS RISE IN ITS WAKE DRY HIGH PRESSURE WILL FILL IN OVER OUR AREA. DIURNAL ACTIVITY FRI AFTN DOES NOT APPEAR TO STAND MUCH CHANCE OF LASTING PAST 00Z SAT...SO A DRY FCST FOR THE FRI NIGHT PERIOD LOOKS FINE. MIN/MAX TEMPS SATURDAY WILL BE A COUPLE DEGREES BELOW CLIMO. SUBSIDENCE BENEATH THE HIGH APPEARS TO BE ENOUGH TO STIFLE ANY DIURNAL CONVECTION SATURDAY EVEN WITH A WEAK UPPER WAVE PASSING OVERHEAD. HOWEVER...BY SUNDAY THE HIGH WILL HAVE SHIFTED TO THE SOUTHEAST COAST. THE SUBSIDENCE INVERSION IS A BIT WEAKER AND LAPSE RATES BENEATH IT A BIT BETTER. WE ALSO LOOK TO WARM A LITTLE MORE...MAXES RETURNING TO ABOUT CLIMO. LOW POPS ARE SUGGESTED BY THE NAM/GFS INVOF THE BLUE RIDGE WHERE RELATIVELY SHALLOW CONVECTION COULD FIRE. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 100 PM THU...HIGH PRESSURE INITIALLY OVER THE EAST COAST SUNDAY NIGHT WILL SHIFT EWD INTO A BERMUDA HIGH CONFIGURATION OVER THE SUBSEQUENT FEW DAYS. UPPER HEIGHTS AND THICKNESSES GRADUALLY INCREASE OVER THE SOUTHEAST AS A RESULT...SO WE CAN EXPECT TEMPS TO RISE A BIT ABOVE NORMAL BY MIDWEEK. GULF FLOW WILL ALLOW AN UPWARD TREND IN AFTERNOON INSTABILITY THRU THE PERIOD...SUGGESTING INCREASING POPS EACH DAY. HOWEVER THEY REMAIN LOW ENOUGH TO MITIGATE SEVERE THREAT. OPERATIONAL GFS/EC AS WELL AS MOST GEFS MEMBERS INDICATE AN INVERTED TROUGH DEVELOPING ON THE SRN BOUNDARY OF THE BERMUDA HIGH BY LATE TUE...WHICH DRIFTS NWD AND CLOSES OFF BY EARLY THU. THERE IS SOME SPREAD ON HOW FAR WEST THIS FEATURE TRACKS...THE EC KEEPING IT NEAR THE ATLANTIC COAST VICE THE GFS AND GEFS CONSENSUS TAKING IT E OF THE BAHAMAS. IT APPEARS UNLIKELY TO BRING ANY PRECIP TO OUR AREA BASED ON THE CURRENT PROGS. && .AVIATION /21Z THURSDAY THROUGH TUESDAY/... AT KCLT...AN UPPER LEVEL CLOSED LOW WILL APPROACH FROM THE NW THIS EVENING. ISOLD TO SCT SHOWERS HAVE BROKEN OUT AHEAD OF THE SYSTEM...BUT WITH NO THUNDER REPORTED ACROSS THE WRN CAROLINAS SO FAR. THERE REMAINS THE POTENTIAL FOR ISOLD TSRA AMONG THE SCT TO NUMEROUS SHOWERS...BUT TEMPO SHRA WILL BE PREFERRED AT THE AIRFIELD. EXPECT WNW FLOW TO CONTINUE THROUGH LATE AFTN...WITH WINDS TURNING MORE NW THEN N TONIGHT WITH A COLD FROPA. STRATOCUMULUS VFR CIGS WILL LIKELY PERSIST THROUGH THE REMAINDER OF THE TAF PERIOD IN MOIST NRLY FLOW. ALTHOUGH THUNDER IS NOT EXPECTED AT THE AIRFIELD...ANY TSRA WOULD LIKELY CONTAIN SMALL HAIL. ELSEWHERE...SHRA/TSRA COVERAGE WILL INCREASE MAINLY FROM KAVL TO KHKY THROUGH LATE AFTERNOON...WITH SCATTERED SHRA COVERAGE EVENTUALLY EXPANDING SWD TOWARD THE UPSTATE TAF SITES. ANY TSRA THAT FORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL GIVEN THE LOW FREEZING LEVELS. VCSH WILL LIKELY CONTINUE THROUGH THE TAF PERIOD AT KAVL TO POSSIBLY KHKY WITH THE PASSING UPPER COLD POOL AND MOIST NRLY FLOW. EXPECT MAINLY NW WINDS...EXCEPT BRIEFLY WSW AT KGMU AND KGSP THIS AFTN IN WEAK LEE TROUGHING. LOW END GUSTS ARE LIKELY AT KAVL. FLOW WILL BECOME MORE NRLY TONIGHT THROUGH FRI AS THE UPPER LOW MOVES EAST. EXPECT VFR CONDITIONS THROUGHOUT...ALTHOUGH MVFR CIGS COULD APPROACH KAVL IN THE FRENCH BROAD VALLEY IN MOIST NW FLOW OVERNIGHT. OUTLOOK...DRY HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA LATE FRIDAY THROUGH THE WEEKEND. RETURN FLOW MOISTURE WILL ONLY SLOWLY REDEVELOP EARLY NEXT WEEK. CONFIDENCE TABLE... 20-02Z 02-08Z 08-14Z 14-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% MED 77% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% 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 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JPT NEAR TERM...HG/JDL SHORT TERM...WIMBERLEY LONG TERM...WIMBERLEY AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
236 PM EDT THU APR 30 2015 .SYNOPSIS... AS A LOW PRESSURE SYSTEM GRADUALLY MOVES OFFSHORE TONIGHT AND TOMORROW...DRIER AIR WILL OVERSPREAD THE REGION AND REMAIN IN PLACE THROUGH EARLY NEXT WEEK. THIS PATTERN WILL BE SLOW TO CHANGE AND WILL FAVOR MOSTLY DRY AND MILD CONDITIONS THROUGH MID WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 225 PM EDT THU...A CLOSED 500 MB LOW SPINNING OVER THE OHIO VALLEY WILL MOVE SE ACROSS THE APPALACHIANS TONIGHT. AHEAD OF THIS SYSTEM...REGIONAL RADAR COVERAGE HAS INCREASED FROM SE KY TO THE SRN APPALACHIANS. THE LATEST HRRR MODEL RUNS INDICATE SEVERAL ROUNDS OF SCATTERED CONVECTION CROSSING THE REGION THROUGH THE EVENING HOURS...IMPACTING LOCATIONS FARTHER S WITH TIME AS A COLD FRONT PUSHES THROUGH THE AREA. STEEP MID LEVEL LAPSE RATES AROUND 7 DEG C/KM OR BETTER WILL TRAVERSE THE AREA WITH THE UPPER COLD POCKET...ESPECIALLY THE INTERSTATE 40 CORRIDOR. IN ADDITION... FREEZING LEVELS AT OR BELOW 8 KFT WILL CONTRIBUTE TO SMAIL HAIL POTENTIAL WITH ANY BETTER CONVECTIVE ELEMENTS. SHEAR COULD BE A BIT BETTER IN SRN SECTIONS THIS EVENING...BUT THE WIND DOES NOT APPEAR TO POSE MUCH THREAT GIVEN THE LIMITED DCAPE AND SHALLOW TOPS. THE HWO MENTION ADVERTISING SMALL HAIL WITH ANY THUNDER WILL BE MAINTAINED. THE COLD CORE LOW WILL PASS OVERHEAD TONIGHT...WITH SOME MEASURE OF NW FLOW MOISTURE PERSISTING ALONG THE SPINE OF THE SRN APPALACHIANS INTO FRI MORNING. CONTINUED MTN SHOWERS FROM STEEP LAPSE RATES WILL BE THE MAIN CONCERN. ALTHOUGH 850 MB TEMPS SHOULD STAY JUST ABOVE FREEZING...ANY BETTER SHOWER RATES COULD BRING SNOW LEVELS DOWN INTO THE HIGHER TERRAIN. ANY SNOW ACCUMS SHOULD BE LIGHT AND CONFINED TO THE RIDGE TOPS...BUT FLURRIES/RIME/GRAUPEL UNDER ANY HEAVIER SHOWERS CANNOT BE RULED OUT DOWN INTO THE MTN VALLEYS. ALSO CANNOT RULE OUT ISOLD ADVECTIVE FREEZE ACROSS THE HIGHEST PEAKS OVERNIGHT...BUT NO WARNING PRODUCT SHOULD BE NEEDED. THE CLOSED H5 LOW SHOULD MOVE OFF TO THE EAST FRI MORNING...WITH DEEP LAYER NRLY FLOW IN PLACE ACROSS THE FORECAST AREA. MOISTURE IN THE NRLY FLOW WILL AFFECT MAINLY THE FOOTHILLS AND PIEDMONT OF WRN NC FRI. FAIRLY STEEP LAPSE RATES WILL KEEP THE SHOWER POTENTIAL GOING THROUGH FRI. WILL FEATURE MAXES A BIT BELOW GUIDANCE CONSENSUS GIVEN THE COLD AIR STRATOCUMULUS SKY COVER. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... AS OF 200 PM THU...CLOSED UPPER LOW WILL MOVE FURTHER OUT OVER THE ATLANTIC FRI NIGHT INTO SAT...AND AS HEIGHTS RISE IN ITS WAKE DRY HIGH PRESSURE WILL FILL IN OVER OUR AREA. DIURNAL ACTIVITY FRI AFTN DOES NOT APPEAR TO STAND MUCH CHANCE OF LASTING PAST 00Z SAT...SO A DRY FCST FOR THE FRI NIGHT PERIOD LOOKS FINE. MIN/MAX TEMPS SATURDAY WILL BE A COUPLE DEGREES BELOW CLIMO. SUBSIDENCE BENEATH THE HIGH APPEARS TO BE ENOUGH TO STIFLE ANY DIURNAL CONVECTION SATURDAY EVEN WITH A WEAK UPPER WAVE PASSING OVERHEAD. HOWEVER...BY SUNDAY THE HIGH WILL HAVE SHIFTED TO THE SOUTHEAST COAST. THE SUBSIDENCE INVERSION IS A BIT WEAKER AND LAPSE RATES BENEATH IT A BIT BETTER. WE ALSO LOOK TO WARM A LITTLE MORE...MAXES RETURNING TO ABOUT CLIMO. LOW POPS ARE SUGGESTED BY THE NAM/GFS INVOF THE BLUE RIDGE WHERE RELATIVELY SHALLOW CONVECTION COULD FIRE. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 100 PM THU...HIGH PRESSURE INITIALLY OVER THE EAST COAST SUNDAY NIGHT WILL SHIFT EWD INTO A BERMUDA HIGH CONFIGURATION OVER THE SUBSEQUENT FEW DAYS. UPPER HEIGHTS AND THICKNESSES GRADUALLY INCREASE OVER THE SOUTHEAST AS A RESULT...SO WE CAN EXPECT TEMPS TO RISE A BIT ABOVE NORMAL BY MIDWEEK. GULF FLOW WILL ALLOW AN UPWARD TREND IN AFTERNOON INSTABILITY THRU THE PERIOD...SUGGESTING INCREASING POPS EACH DAY. HOWEVER THEY REMAIN LOW ENOUGH TO MITIGATE SEVERE THREAT. OPERATIONAL GFS/EC AS WELL AS MOST GEFS MEMBERS INDICATE AN INVERTED TROUGH DEVELOPING ON THE SRN BOUNDARY OF THE BERMUDA HIGH BY LATE TUE...WHICH DRIFTS NWD AND CLOSES OFF BY EARLY THU. THERE IS SOME SPREAD ON HOW FAR WEST THIS FEATURE TRACKS...THE EC KEEPING IT NEAR THE ATLANTIC COAST VICE THE GFS AND GEFS CONSENSUS TAKING IT E OF THE BAHAMAS. IT APPEARS UNLIKELY TO BRING ANY PRECIP TO OUR AREA BASED ON THE CURRENT PROGS. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... AT KCLT...AN UPPER LEVEL CLOSED LOW WILL APPROACH FROM THE NW THIS EVENING. ISOLD TO SCT SHOWERS HAVE BROKEN OUT AHEAD OF THE SYSTEM...BUT WITH NO THUNDER REPORTED ACROSS THE WRN CAROLINAS SO FAR. THERE REMAINS THE POTENTIAL FOR ISOLD TSRA AMONG THE SCT TO NUMEROUS SHOWERS...BUT TEMPO SHRA WILL BE PREFERRED AT THE AIRFIELD. EXPECT WNW FLOW TO CONTINUE THROUGH LATE AFTN...WITH WINDS TURNING MORE NW THEN N TONIGHT WITH A COLD FROPA. STRATOCUMULUS VFR CIGS WILL LIKELY PERSIST THROUGH THE REMAINDER OF THE TAF PERIOD IN MOIST NRLY FLOW. ALTHOUGH THUNDER IS NOT EXPECTED AT THE AIRFIELD...ANY TSRA WOULD LIKELY CONTAIN SMALL HAIL. ELSEWHERE...SHRA/TSRA COVERAGE WILL INCREASE MAINLY FROM KAVL TO KHKY THROUGH LATE AFTERNOON...WITH SCATTERED SHRA COVERAGE EVENTUALLY EXPANDING SWD TOWARD THE UPSTATE TAF SITES. ANY TSRA THAT FORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL GIVEN THE LOW FREEZING LEVELS. VCSH WILL LIKELY CONTINUE THROUGH THE TAF PERIOD AT KAVL TO POSSIBLY KHKY WITH THE PASSING UPPER COLD POOL AND MOIST NRLY FLOW. EXPECT MAINLY NW WINDS...EXCEPT BRIEFLY WSW AT KGMU AND KGSP THIS AFTN IN WEAK LEE TROUGHING. LOW END GUSTS ARE LIKELY AT KAVL. FLOW WILL BECOME MORE NRLY TONIGHT THROUGH FRI AS THE UPPER LOW MOVES EAST. EXPECT VFR CONDITIONS THROUGHOUT...ALTHOUGH MVFR CIGS COULD APPROACH KAVL IN THE FRENCH BROAD VALLEY IN MOIST NW FLOW OVERNIGHT. OUTLOOK...DRY HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA LATE FRIDAY THROUGH THE WEEKEND. RETURN FLOW MOISTURE WILL ONLY SLOWLY REDEVELOP EARLY NEXT WEEK. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 86% HIGH 95% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% 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 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JPT NEAR TERM...HG SHORT TERM...WIMBERLEY LONG TERM...WIMBERLEY AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
203 PM EDT THU APR 30 2015 .SYNOPSIS... LOW PRESSURE WILL DEEPEN AS IT TRACKS OFFSHORE TODAY. IN THE WAKE OF THIS SYSTEM...DRY AIR WILL OVERSPREAD THE REGION TODAY AND SHOULD CONTINUE THROUGH THE WEEKEND. THE PATTERN WILL UNDERGO SLOW CHANGES THROUGH NEXT WEEK...FAVORING DRY AND MILD CONDITIONS. && .NEAR TERM /THROUGH FRIDAY/... AS OF 145 PM EDT THU...A CLOSED 500 MB LOW PRESSURE SYSTEM WILL MOVE FROM THE OH VALLEY THIS AFTN TO THE SRN APPALACHIANS TONIGHT. AHEAD OF THIS SYSTEM...REGIONAL RADAR COVERAGE IS INCREASING ACROSS SE KY...SW VA...AND ERN TN. THE LATEST HRRR HAS THE FIRST ROUND OF CONVECTION DEVELOPING EWD OFF THE BLUE RIDGE THIS AFTN...WHILE A SECOND ROUND FORMS CIRCA 20Z OVER THE MTNS. THERE COULD WELL BE THREE WAVES OF CONVECTION THROUGH EVENING...EACH A LITTLE FARTHER S...AS A SFC COLD FRONT WORKS SE THROUGH THE REGION. STEEP MID LEVEL LAPSE RATES AROUND 7 DEG C/KM OR BETTER WILL TRAVERSE THE AREA WITH THE UPPER COLD POCKET...ESPECIALLY THE INTERSTATE 40 CORRIDOR. THIS WILL COMBINE WITH FREEZING LEVELS AT OR BELOW 8 KFT TO YIELD HAIL POTENTIAL WITH ANY BETTER CONVECTIVE ELEMENTS. SHEAR COULD BE A BIT BETTER IN SRN SECTIONS THIS EVENING...BUT THE WIND DOES NOT APPEAR TO POSE MUCH THREAT WITH LIMITED DCAPE AND SHALLOW TOPS. THE HWO MENTION ADVERTISING HAIL WILL BE MAINTAINED. THE COLD CORE LOW WILL PASS OVERHEAD TONIGHT...WITH SOME MEASURE OF NW FLOW MOISTURE THEN PERSISTING ALONG THE SPINE OF THE SRN APPALACHIANS INTO FRI MORNING. CONTINUED MTN SHOWERS FROM STEEP LAPSE RATES WILL BE THE MAIN CONCERN. ALTHOUGH 850 MB TEMPS SHOULD STAY JUST ABOVE FREEZING...ANY BETTER SHOWER RATES COULD BRING SNOW LEVELS DOWN INTO THE HIGHER TERRAIN. ANY SNOW ACCUMS SHOULD BE LIGHT AND CONFINED TO THE RIDGE TOPS...BUT FLURRIES/RIME/GRAUPEL UNDER ANY HEAVIER SHOWERS CANNOT BE RULED OUT DOWN IN THE MTN VALLEYS. ALSO CANNOT RULE OUT ADVECTIVE FREEZE ACROSS THE HIGHEST PEAKS OVERNIGHT. THE CLOSED H5 LOW SHOULD MOVE OFF TO THE EAST FRI MORNING...WITH DEEP LAYER NRLY FLOW IN PLACE ACROSS THE FORECAST AREA. MOISTURE IN THE NRLY FLOW WILL AFFECT MAINLY THE FOOTHILLS AND PIEDMONT OF WRN NC FRI. FAIRLY STEEP LAPSE RATES WILL KEEP THE SHOWER POTENTIAL GOING THROUGH FRI. WILL FEATURE MAXES A BIT BELOW GUIDANCE CONSENSUS GIVEN THE COLD AIR STRATOCU POTENTIAL. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/... AS OF 240 AM THURSDAY...SHORT RANGE MODELS INDICATE THAT THE AXIS OF A LONGWAVE TROF WILL RIPPLE EAST OF THE FORECAST AREA DURING THE DAYLIGHT HOURS ON FRIDAY. IN THE WAKE OF THE TROF...COOL AND MOIST H85 WINDS WILL CONTINUE FROM A NORTH-NORTHWEST DIRECTION ACROSS THE NC MTNS...WEAKENING DURING THE EVENING. THE COMBINATION OF WEAK UPSLOPE FLOW ON THE NORTHWEST SLOPES OF THE APPALACHIANS AND WEAK INSTABILITY SHOULD SUPPORT A FEW -SHRA ON FRIDAY. IN ADDITION...A VORT MAX MAY PROVIDE ENOUGH LIFT TO RESULT IN ANOTHER AREA OF -SHRA ACROSS THE I-77 CORRIDOR DURING THE MORNING HOURS. USING A BLEND OF PREFERRED TEMPERATURE GUIDANCE...I WILL FORECAST U50S ACROSS THE MTNS WITH MID TO UPPER 60S EAST. FRIDAY NIGHT THROUGH SATURDAY...MID LEVEL HEIGHTS WILL STEADILY RISE FROM THE WEST ACROSS THE WESTERN CAROLINAS AND NE GA. THE CENTER OF A LARGE AREA OF HIGH PRESSURE WILL SLIDE ACROSS THE SOUTHEAST U.S. I WILL FORECAST DRY CONDITIONS THROUGH SATURDAY. TEMPERATURES SHOULD BEGIN THE DAY NEAR NORMAL...WITH HIGH TEMPERATURES WITHIN 3 TO 4 DEGREES OF NORMAL. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 3 AM THURSDAY...THE GFS AND ECMWF INDICATE THAT A WEAK MID LEVEL REX BLOCK WILL DEVELOP OVER THE SOUTHERN CONUS EARLY NEXT WEEK...PEAKING ON TUESDAY. AT THE SFC...VERY LITTLE CHANGE FROM DAY TO DAY...THE CENTER OF A LARGE AREA OF HIGH PRESSURE WILL REMAIN ACROSS THE SOUTHEAST. OVERALL...TEMPERATURES WILL RANGE 2 TO 4 DEGREES ABOVE NORMAL...LIGHT WINDS...AND PARTLY CLOUDY SKY CONDITIONS. EAST H85 WINDS SHOULD SUPPORT A GRADUAL RISE AND HUMIDITY ACROSS THE WESTERN CAROLINAS AND NE GA. WEAK DIURNAL INSTABILITY AND PERIODS OF UPSLOPE FLOW MAY RESULT IN LOW COVERAGE OF CONVECTION DURING THE MID TO LATE AFTERNOON...PRIMARILY ON TUESDAY AND WEDNESDAY. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AT KCLT...AN UPPER LEVEL CLOSED LOW WILL APPROACH FROM THE NW THIS AFTN AND EVENING. ISOLD TO SCT SHOWERS HAVE BROKEN OUT AHEAD OF THE SYSTEM...BUT WITH NO THUNDER SO FAR. THERE REMAINS THE POTENTIAL FOR ISOLD TSRA AMONG THE SCT TO NUMEROUS SHOWERS...BUT TEMPO SHRA WILL BE PREFERRED AT THE AIRFIELD. EXPECT WNW FLOW TO CONTINUE THROUGH LATE AFTN...WITH WINDS TURNING MORE NW THEN N TONIGHT WITH A COLD FROPA. STRATOCUMULUS VFR CIGS WILL LIKELY PERSIST THROUGH THE REMAINDER OF THE TAF PERIOD IN MOIST NRLY FLOW. ALTHOUGH THUNDER IS NOT EXPECTED AT THE AIRFIELD...ANY TSRA WOULD LIKELY CONTAIN SMALL HAIL. ELSEWHERE...SHRA/TSRA COVERAGE WILL INCREASE MAINLY FROM KAVL TO KHKY THROUGH LATE AFTERNOON...WITH SCATTERED SHRA COVERAGE EVENTUALLY EXPANDING SWD TOWARD THE UPSTATE TAF SITES. ANY TSRA THAT FORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL GIVEN THE LOW FREEZING LEVELS. VCSH WILL LIKELY CONTINUE THROUGH THE TAF PERIOD AT KAVL TO POSSIBLY KHKY WITH THE PASSING UPPER COLD POOL AND MOIST NRLY FLOW. EXPECT MAINLY NW WINDS...EXCEPT BRIEFLY WSW AT KGMU AND KGSP THIS AFTN IN WEAK LEE TROUGHING. LOW END GUSTS ARE LIKELY AT KAVL. FLOW WILL BECOME MORE NRLY TONIGHT THROUGH FRI AS THE UPPER LOW MOVES EAST. EXPECT VFR CONDITIONS THROUGHOUT...ALTHOUGH MVFR CIGS COULD APPROACH KAVL IN THE FRENCH BROAD VALLEY IN MOIST NW FLOW OVERNIGHT. OUTLOOK...DRY HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA LATE FRIDAY THROUGH THE WEEKEND. RETURN FLOW MOISTURE WILL ONLY SLOWLY REDEVELOP EARLY NEXT WEEK. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 86% HIGH 95% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% 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 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...NED NEAR TERM...HG SHORT TERM...NED LONG TERM...NED AVIATION...HG
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1228 PM CDT THU APR 30 2015 .UPDATE... ISSUED AT 1225 PM CDT THU APR 30 2015 SEE UPDATED AVIATION DISCUSSION BELOW. UPDATE ISSUED AT 1039 AM CDT THU APR 30 2015 STARTED RED FLAG EARLY AS TEMPERATURES HAVE ALREADY JUMPED INTO THE 60S WITH RH VALUES DOWN IN THE 20S. WINDS HAVE PEAKED AT KMBG/KABR AROUND 30MPH AS WELL. FOCUS SHIFTS TO AFTERNOON CONVECTION. HRRR INDICATES HIGH/SFC BASED CONVECTION DEVELOPING BETWEEN KMBG/KABR THIS AFTERNOON...WITH BASES ABOVE 0C...SO POTENTIALLY A DRY MICROBURST ENVIRONMENT. NAM SOUNDINGS ARE A TAD MORE HUMID...BUT CIGS WILL LIKELY STILL BE ABOVE 7KFT AND HAVE TO OVERCOME A VERY DRY SUBCLOUD LAYER FOR PRECIPITATION TO REACH THE SURFACE. AS FOR TIMING...THE 12Z NAM IS STILL RATHER CONSISTENT...IN LINE WITH FORECAST AND PREVIOUS NAM/GFS GUIDANCE. THE HRRR IS MUCH FARTHER EAST...SO AT THIS POINT WILL KEEP CURRENT PROGRESSION OF POPS ACROSS THE CWA. && .SHORT TERM...(TODAY THROUGH SATURDAY AFTERNOON) ISSUED AT 347 AM CDT THU APR 30 2015 FIRST ITEM OF DISCUSSION WILL BE THE VERY HIGH FIRE DANGER DEVELOPING ACROSS THE AREA THIS AFTERNOON. FORECAST RH VALUES ARE STILL EXPECTED TO RANGE FROM THE UPPER TEENS TO LOW 20S EAST OF THE MISSOURI RIVER. SOUTH WINDS WILL ALSO INCREASE THIS AFTERNOON AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF AN APPROACHING COLD FRONT. SHOULD BE ABLE TO SEE SOME WIND GUSTS MEET OR EXCEED 25 MPH ACROSS NORTH CENTRAL INTO NORTHEAST SD. PREVIOUS SHIFT HAD ALREADY ISSUED A RED FLAG WARNING FOR FIRE ZONES 269 AND 271. BASED ON CURRENT FORECAST RH AND WIND GUSTS...HAVE DECIDED TO EXPAND RED FLAG WARNING TO INCLUDE FIRE ZONES 272 AND 273 AS WELL. WIND SPEEDS MAY BE A BIT MARGINAL...BUT SHOULD STILL BE AROUND OR JUST OVER 25 MPH GUSTS FOR MUCH OF THE AREA. MIXED LAYER WINDS ARE NOT ALL TOO IMPRESSIVE...ONLY AROUND 20 KNOTS. BUT SHOULD BE ENOUGH MOMENTUM TO SEE HIGHER GUSTS. WILL ALSO BE WATCHING A COLD FRONT MOVING INTO THE WESTERN CWA LATE THIS AFTERNOON. ALL HI RES MODELS ARE SHOWING SCT ACTIVITY MOVING INTO CORSON AND DEWEY COUNTIES AFTER 21Z SO HAVE INCREASED POPS AND WENT WITH COVERAGE WORDING INSTEAD OF UNCERTAINTY. HI RES SIMULATED REFLECTIVITY ALSO SUGGESTING ACTIVITY HOLDS TOGETHER ALONG THE FRONT IN SOME FORM OF A BROKEN LINE AS IT TRACKS EAST ACROSS THE CWA. HAVE INCREASED POPS OVERNIGHT A BIT AS WELL AND CONTINUED THE COVERAGE WORDING. ONLY MINIMAL INSTABILITY PRESENT BUT JUST ENOUGH TO SUPPORT SOME EMBEDDED THUNDERSHOWERS AS WELL. ACTIVITY ASSOCIATED WITH THIS FRONT LOOKS TO CLEAR THE CWA BY 12Z FRIDAY. FRIDAY ITSELF LOOKING VERY PLEASANT AS SFC HIGH PRESSURE MOVES ACROSS THE REGION. WINDS WILL BE FAIRLY LIGHT WITH SUNNY SKIES AND TEMPS IN THE 70S FOR HIGHS. WILL CONTINUE WITH DRY CONDITIONS FRIDAY NIGHT. ON SATURDAY...MID LEVEL TEMPS WARM QUITE A BIT AS SOUTHERLY FLOW INCREASES. GOOD MIXING DEVELOPS BY AFTERNOON WITH IMPRESSIVE WARMING AT THE SFC. WIDESPREAD 80S ARE EXPECTED AND ANTICIPATE SATURDAY TO BE THE WARMEST DAY OF THE SPRING THUS FAR. WILL ALSO HAVE TO WATCH THE ARRIVAL OF A SFC TROUGH SATURDAY AFTERNOON WHICH COULD SPARK A FEW SHOWERS OR STORMS. MOISTURE MAY BE LIMITED SO WILL ONLY INCLUDE SLIGHT CHANCE POPS AT THIS TIME. .LONG TERM...(SATURDAY EVENING THROUGH WEDNESDAY) ISSUED AT 347 AM CDT THU APR 30 2015 A WEAK FRONT/TROUGH WILL MOVE THROUGH THE PLAINS ON SAT NIGHT/SUNDAY BRINGING A CHANCE OF SHOWERS AND TSTORMS. ZONAL FLOW ALOFT AND HIGH PRESSURE NEAR THE SURFACE WILL KEEP SUNDAY NIGHT THROUGH MONDAY NIGHT RELATIVELY QUIET...THOUGH SUPERBLEND KEEPS SOME POPS ACROSS THE SOUTHERN CWA DUE TO A WEAK SHORTWAVE THAT MAY BRING SHOWERS. THE PATTERN BEGINS TO SHIFT TUESDAY NIGHT AS A POTENT UPPER LOW STARTS TO MOVE EAST. COUPLED WITH SOUTHERLY FLOW AT THE SFC AHEAD OF AN APPROACHING ATMOSPHERICALLY STACKED LOW AND AN OPEN GULF STARTING ON WED PRECIP CHANCES WILL INCREASE GREATLY. BOTH THE ECMWF AND THE GFS ARE IN GOOD AGREEMENT ON THIS MID WEEK SYSTEM. IF THIS PATTERN PERSISTS AND IT DOES NOT SHIFT SOUTH AS HAS BEEN THE TREND...THIS LOW WILL BE ONE OF THE MORE WELL DEVELOPED SYNOPTIC SYSTEMS THE REGION HAS SEEN ALL YEAR. TEMPERATURES WILL CLIMB INTO THE 70S THROUGH THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1225 PM CDT THU APR 30 2015 VFR CONDITIONS WILL PREVAIL ACROSS THE AREA THROUGH THE TAF PERIOD. LOOK FOR A LINE OF RAIN SHOWERS TO PUSH ACROSS THE CWA DURING THE LATE AFTERNOON AND OVERNIGHT HOURS. AN ISOLATED THUNDERSTORM OR TWO ARE POSSIBLE AS WELL...BUT WILL NOT MENTION IN ANY TAF SITES DUE TO UNCERTAINTY OF WHERE DEVELOPMENT MAY BE. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR SDZ269-271>273. MN...NONE. && $$ UPDATE...CONNELLY SHORT TERM...TMT LONG TERM...WISE AVIATION...PARKIN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
1053 AM CDT THU APR 30 2015 .UPDATE... ISSUED AT 1039 AM CDT THU APR 30 2015 STARTED RED FLAG EARLY AS TEMPERATURES HAVE ALREADY JUMPED INTO THE 60S WITH RH VALUES DOWN IN THE 20S. WINDS HAVE PEAKED AT KMBG/KABR AROUND 30MPH AS WELL. FOCUS SHIFTS TO AFTERNOON CONVECTION. HRRR INDICATES HIGH/SFC BASED CONVECTION DEVELOPING BETWEEN KMBG/KABR THIS AFTERNOON...WITH BASES ABOVE 0C...SO POTENTIALLY A DRY MICROBURST ENVIRONMENT. NAM SOUNDINGS ARE A TAD MORE HUMID...BUT CIGS WILL LIKELY STILL BE ABOVE 7KFT AND HAVE TO OVERCOME A VERY DRY SUBCLOUD LAYER FOR PRECIPITATION TO REACH THE SURFACE. AS FOR TIMING...THE 12Z NAM IS STILL RATHER CONSISTENT...IN LINE WITH FORECAST AND PREVIOUS NAM/GFS GUIDANCE. THE HRRR IS MUCH FARTHER EAST...SO AT THIS POINT WILL KEEP CURRENT PROGRESSION OF POPS ACROSS THE CWA. && .SHORT TERM...(TODAY THROUGH SATURDAY AFTERNOON) ISSUED AT 347 AM CDT THU APR 30 2015 FIRST ITEM OF DISCUSSION WILL BE THE VERY HIGH FIRE DANGER DEVELOPING ACROSS THE AREA THIS AFTERNOON. FORECAST RH VALUES ARE STILL EXPECTED TO RANGE FROM THE UPPER TEENS TO LOW 20S EAST OF THE MISSOURI RIVER. SOUTH WINDS WILL ALSO INCREASE THIS AFTERNOON AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF AN APPROACHING COLD FRONT. SHOULD BE ABLE TO SEE SOME WIND GUSTS MEET OR EXCEED 25 MPH ACROSS NORTH CENTRAL INTO NORTHEAST SD. PREVIOUS SHIFT HAD ALREADY ISSUED A RED FLAG WARNING FOR FIRE ZONES 269 AND 271. BASED ON CURRENT FORECAST RH AND WIND GUSTS...HAVE DECIDED TO EXPAND RED FLAG WARNING TO INCLUDE FIRE ZONES 272 AND 273 AS WELL. WIND SPEEDS MAY BE A BIT MARGINAL...BUT SHOULD STILL BE AROUND OR JUST OVER 25 MPH GUSTS FOR MUCH OF THE AREA. MIXED LAYER WINDS ARE NOT ALL TOO IMPRESSIVE...ONLY AROUND 20 KNOTS. BUT SHOULD BE ENOUGH MOMENTUM TO SEE HIGHER GUSTS. WILL ALSO BE WATCHING A COLD FRONT MOVING INTO THE WESTERN CWA LATE THIS AFTERNOON. ALL HI RES MODELS ARE SHOWING SCT ACTIVITY MOVING INTO CORSON AND DEWEY COUNTIES AFTER 21Z SO HAVE INCREASED POPS AND WENT WITH COVERAGE WORDING INSTEAD OF UNCERTAINTY. HI RES SIMULATED REFLECTIVITY ALSO SUGGESTING ACTIVITY HOLDS TOGETHER ALONG THE FRONT IN SOME FORM OF A BROKEN LINE AS IT TRACKS EAST ACROSS THE CWA. HAVE INCREASED POPS OVERNIGHT A BIT AS WELL AND CONTINUED THE COVERAGE WORDING. ONLY MINIMAL INSTABILITY PRESENT BUT JUST ENOUGH TO SUPPORT SOME EMBEDDED THUNDERSHOWERS AS WELL. ACTIVITY ASSOCIATED WITH THIS FRONT LOOKS TO CLEAR THE CWA BY 12Z FRIDAY. FRIDAY ITSELF LOOKING VERY PLEASANT AS SFC HIGH PRESSURE MOVES ACROSS THE REGION. WINDS WILL BE FAIRLY LIGHT WITH SUNNY SKIES AND TEMPS IN THE 70S FOR HIGHS. WILL CONTINUE WITH DRY CONDITIONS FRIDAY NIGHT. ON SATURDAY...MID LEVEL TEMPS WARM QUITE A BIT AS SOUTHERLY FLOW INCREASES. GOOD MIXING DEVELOPS BY AFTERNOON WITH IMPRESSIVE WARMING AT THE SFC. WIDESPREAD 80S ARE EXPECTED AND ANTICIPATE SATURDAY TO BE THE WARMEST DAY OF THE SPRING THUS FAR. WILL ALSO HAVE TO WATCH THE ARRIVAL OF A SFC TROUGH SATURDAY AFTERNOON WHICH COULD SPARK A FEW SHOWERS OR STORMS. MOISTURE MAY BE LIMITED SO WILL ONLY INCLUDE SLIGHT CHANCE POPS AT THIS TIME. .LONG TERM...(SATURDAY EVENING THROUGH WEDNESDAY) ISSUED AT 347 AM CDT THU APR 30 2015 A WEAK FRONT/TROUGH WILL MOVE THROUGH THE PLAINS ON SAT NIGHT/SUNDAY BRINGING A CHANCE OF SHOWERS AND TSTORMS. ZONAL FLOW ALOFT AND HIGH PRESSURE NEAR THE SURFACE WILL KEEP SUNDAY NIGHT THROUGH MONDAY NIGHT RELATIVELY QUIET...THOUGH SUPERBLEND KEEPS SOME POPS ACROSS THE SOUTHERN CWA DUE TO A WEAK SHORTWAVE THAT MAY BRING SHOWERS. THE PATTERN BEGINS TO SHIFT TUESDAY NIGHT AS A POTENT UPPER LOW STARTS TO MOVE EAST. COUPLED WITH SOUTHERLY FLOW AT THE SFC AHEAD OF AN APPROACHING ATMOSPHERICALLY STACKED LOW AND AN OPEN GULF STARTING ON WED PRECIP CHANCES WILL INCREASE GREATLY. BOTH THE ECMWF AND THE GFS ARE IN GOOD AGREEMENT ON THIS MID WEEK SYSTEM. IF THIS PATTERN PERSISTS AND IT DOES NOT SHIFT SOUTH AS HAS BEEN THE TREND...THIS LOW WILL BE ONE OF THE MORE WELL DEVELOPED SYNOPTIC SYSTEMS THE REGION HAS SEEN ALL YEAR. TEMPERATURES WILL CLIMB INTO THE 70S THROUGH THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 630 AM CDT THU APR 30 2015 SOUTHERLY WINDS WILL INCREASE TO 15 TO 30 KTS AHEAD OF A COLD FRONT TODAY. AS THE FRONT MOVES THROUGH LATE THIS AFTERNOON/EVENING WINDS WILL SHIFT TO THE NORTHWEST AND DIMINISH. SOME SHOWERS MAY ACCOMPANY THE FRONT. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR SDZ269-271>273. MN...NONE. && $$ UPDATE...CONNELLY SHORT TERM...TMT LONG TERM...WISE AVIATION...WISE
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1226 PM EDT THU APR 30 2015 .DISCUSSION...MRX BACK UP AND RUNNING AFTER AN AWIPS2 UPGRADE. WAITING FOR ATMOSPHERE TO HEAT UP JUST A BIT MORE AND CAUSE SOME SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO DEVELOP. LATEST NAM AND RAP SHOW THE GREATER COVERAGE THIS AFTERNOON WILL BE ACROSS SW VA AND NE TN...CLOSER TO THE COOLER TEMPERATURES ALOFT. ADJUSTED A FEW SKY AND HOURLY GRIDS TO REFLECT THE WARMER TEMPS AT NOON...DUE MOSTLY TO LESS SKY COVER. NUDGED MAX TEMP GRID UP ALSO BUT ALLOWED FOR COOLER TEMPERATURES BY MID TO LATE AFTERNOON AS CONVECTION POPS ACROSS THE REGION. .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 74 45 70 49 / 30 20 0 0 KNOXVILLE MCGHEE TYSON AIRPORT, TN 70 45 65 49 / 60 30 10 0 OAK RIDGE, TN 70 45 67 48 / 60 30 10 0 TRI CITIES AIRPORT, TN 68 42 64 45 / 60 60 30 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ TG
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
337 AM CDT THU APR 30 2015 .DISCUSSION... IR IMAGERY SHOWING AN UPPER LEVEL SYSTEM CURRENTLY SPINNING OVER LOWER MICHIGAN. THIS FEATURE WILL BE MIDDLE TN`S NEXT WEATHER MAKER AS IT MOVES SOUTHWARD TODAY. MODELS AND THE HRRR DATA ARE ALL IN LINE WITH SPREADING SHOWER ACTIVITY SOUTHWARD THROUGH THE AREA...BEGINNING JUST BEFORE NOON FAR NORTH...AND THEN SPREADING SOUTHWARD ACROSS THE MID STATE THEREAFTER. THE ACTUAL POSITION OF THE UPPER LOW WILL BE OVER EASTERN KY AT 00Z THIS EVENING. MOISTURE WILL EXTEND WELL TO THE WEST OF THE TRACK. THUS...POPS WILL INCREASE FROM WEST TO EAST WITH 50 POPS OVER OUR PLATEAU. AS FOR ANY THUNDER CHANCES...COOLER AIR IS NOTED ALOFT...BUT THE BETTER SHOWALTER AND MID LEVEL THETA-E PARAMETERS WILL BE LOCATED TO OUR EAST. A FEW RESIDUAL SHOWERS WILL LINGER INTO THIS EVENING ACROSS THE PLATEAU...THEN PARTIAL CLEARING IS EXPECTED. HIGH PRESSURE AT THE SFC WILL THEN BUILD IN WITH 1 LAST NIGHT WITH LOW TEMPS IN THE 40S FOR FRI NT. A WARMING TREND WILL THEN COMMENCE WITH HEIGHTS ON THE INCREASE ON INTO THE EXTENDED PERIOD. STILL NO ORGANIZED FRONTAL PASSAGES ARE INDICATED...JUST WARM AND DRY. TEMPERATURES WILL BE A GOOD 5 TO 10 DEGREES BELOW NORMAL THROUGH FRI NT. THEN...WITH THE WARMING TREND...HIGH TEMPS WILL REACHING INTO THE LOWER TO PERHAPS MID 80S BY THE MIDDLE PORTION OF NEXT WEEK. .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 70 43 71 49 / 30 10 0 05 CLARKSVILLE 69 41 69 48 / 20 05 0 05 CROSSVILLE 65 39 64 44 / 50 20 10 10 COLUMBIA 72 44 71 49 / 20 10 0 05 LAWRENCEBURG 72 45 70 48 / 20 10 05 05 WAVERLY 70 42 69 48 / 20 05 0 05 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1152 PM CDT WED APR 29 2015 .DISCUSSION... UPDATED FOR 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 1050 PM CDT WED APR 29 2015/ UPDATE... TEMPERATURES ARE DROPPING OFF A LITTLE QUICKER THAN FORECAST THIS EVENING WITH LIGHT WIND AND CLEAR SKIES. HAVE LOWERED OVERNIGHT LOWS A LITTLE IN MANY LOCATIONS. UPDATED ZONES AND GRIDS HAVE BEEN SENT. JCL && .UPDATE... /ISSUED 720 PM CDT WED APR 29 2015/ AT EARLY EVENING...A FEW SHOWERS WERE PUSHING THROUGH PORTIONS OF EAST CENTRAL AR AND NORTHWEST MS AS THE POTENT UPPER LEVEL DISTURBANCE CONTINUE TO PUSH SOUTH-SOUTHEASTWARD. THE SHOWERS ARE QUICKLY DECREASING IN COVERAGE AND EXPECT THEM TO SOON DISSIPATE. SKIES ARE EXPECTED TO SOON CLEAR ACROSS THE MIDSOUTH FOR THE REMAINDER OF TONIGHT. UPDATED THE ZONE FORECAST AND GRIDS TO REMOVE REMAINDER OF AFTERNOON WORDING. ALSO MADE A FEW TWEAKS TO THE OVERNIGHT LOW TEMPERATURES AND WINDS. UPDATE... /ISSUED 511 PM CDT WED APR 29 2015/ ALSO INCLUDED ISOLATED THUNDERSTORMS ALONG WITH MENTION OF SCATTERED SHOWERS ACROSS NORTHEAST AR. LIGHTNING HAS BEEN DETECTED WITH WEAK SURFACE BASED INSTABILITY. UPDATE... /ISSUED 456 PM CDT WED APR 29 2015/ SCATTERED SHOWERS ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE ARE MOVING SOUTH-SOUTHEASTWARD THROUGH NORTHEAST AR. LIGHT RAIN WAS REPORTED AT CORNING AR WHILE WALNUT RIDGE AR REPORTED A WIND GUST TO NEAR 40 MPH WITH ONE OF THE SHOWERS. THE LATEST HRRR SHOWS THESE SHOWERS CONTINUING TO PUSH SOUTH-SOUTHEASTWARD THROUGH NORTHEAST AR OVER THE NEXT FEW HOURS. WHILE THE HRRR DOES MOVE THEM INTO MEMPHIS...THE RAP DISSIPATES THE SHOWERS WITH SUNSET BEFORE THEY REACH MEMPHIS. WILL MONITOR THIS...BUT FOR NOW ONLY INCLUDED THE SHOWERS ACROSS NORTHEAST AR. JCL && .DISCUSSION... /ISSUED 332 PM CDT WED APR 29 2015/ CURRENTLY AS OF 3PM... TEMPERATURES ARE IN THE 70S THROUGHOUT THE MIDSOUTH FOR THE FIRST TIME SINCE SATURDAY BUT STILL ARE A FEW DEGREES BELOW LATE APRIL NORMALS. SKIES ARE MOSTLY CLEAR THROUGHOUT THE CWA BUT THAT WILL SOON CHANGE AS AN UPPER LEVEL SHORTWAVE REVOLVING AROUND A CLOSED LOW NORTH OF THE GREAT LAKES HAS BEGUN TO MOVE INTO THE REGION INCREASING CLOUDINESS MAINLY IN THE WESTERN AND SOUTHERN COUNTIES OF THE MIDSOUTH. KNQA RADAR IS ALREADY DEPICTING LIGHT SHOWERS MOVING INTO THE FAR NORTHEASTERN CWA... HOWEVER IT IS LIKELY THAT THIS PRECIPITATION IS NOT REACHING THE GROUND DUE TO REALLY DRY SURFACE AIR IN PLACE. SHORT TERM...THE AFOREMENTIONED SHORTWAVE WILL CONTINUE TO PUSH THROUGH THE REGION OVER NIGHT. MODELS AGREE ON VERY LITTLE QPF WITH THIS DISTURBANCE AND THE MAJORITY OF THE MIDSOUTH WILL STAY DRY. HOWEVER.. THE LATEST RUN OF THE HRRR DEPICTS SOME VERY ISOLATED SHOWER ACTIVITY MOVING THROUGH NORTHEASTERN ARKANSAS AND NORTH WEST MISSISSIPPI THIS EVENING. ON A BROADER SCALE... AN UPPER LEVEL TROF WILL REMAIN OVER THE EASTERN UNITED STATES WHILE UPPER RIDGING TAKES PLACE NEAR THE MISSISSIPPI RIVER VALLEY. THE CLOSED LOW OVER THE GREATS LAKES WILL PUSH SOUTHWARD THROUGH THE OHIO VALLEY REGION JUST EAST OF THE MIDSOUTH ON THURSDAY. THE ONLY EFFECT THIS SYSTEM WILL HAVE ON OUR CWA IS SLIGHTLY RAISED POPS FOR THE COUNTIES IN WEST TENNESSEE NEAR THE TENNESSEE RIVER... HOWEVER MOST OF THE PRECIP WILL STAY FAR EAST OF OUR CWA. ABNORMALLY DRY AIR ASSOCIATED WITH A BROAD SURFACE HIGH WILL BEGIN TO FILTER INTO THE MIDSOUTH THURSDAY. NORTHWESTERLY FLOW WILL KEEP TEMPERATURES SLIGHTLY COOLER THAN NORMAL OVER THE NEXT FEW DAYS AS HIGH PRESSURE REMAINS PARKED OVER THE MIDSOUTH. LONG TERM... TEMPERATURES WILL INCREASE TO NEAR NORMAL VALUES BY THE WEEKEND AND ABOVE AVERAGE BY EARLY NEXT WEEK AS THE SURFACE HIGH SLOWLY SHIFTS EAST AND FLOW BECOMES MORE SOUTHERLY. THE FORECAST WILL REMAIN DRY THROUGH MIDWEEK NEXT WEEK. MODELS AGREE ON A MORE DYNAMIC WEATHER PATTERN SETTING UP BY LATE NEXT WEEK AS A DEEP TROF APPROACHES THE REGION. JPM3 && .AVIATION... 06Z TAF CYCLE VFR WITH PATCHY MIDLEVEL CLOUDS ASSOCIATED WITH A WEAK COLD FRONT. LIGHT WINDS OVERNIGHT WILL BECOME GUSTY FROM THE NORTHWEST BEFORE NOON. POST FRONTAL WINDS WILL VEER NORTH AND WEAKEN NEAR SUNSET. JAB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
908 PM EDT FRI MAY 1 2015 .SYNOPSIS... AN UPPER LEVEL LOW PRESSURE SYSTEM WILL PROGRESS EASTWARD...OUT OF THE REGION OVERNIGHT. HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND AND BE POSITIONED ACROSS OUR REGION INTO MUCH OF NEXT WEEK. OUR NEXT BEST CHANCE OF PRECIPITATION WILL COME DURING THE MIDDLE OF NEXT WEEK WHEN A BACKDOOR COLD FRONT APPROACHES OUR AREA. && .NEAR TERM /THROUGH SATURDAY/... AS OF 908 PM EDT FRIDAY... UPPER LOW WILL DRIFT EAST INTO THE ATLANTIC OCEAN OVERNIGHT AND SATURDAY. A BROAD RIDGE OF HIGH PRESSURE WILL BUILD EAST FROM THE OHIO VALLEY FOR SATURDAY. KFCX WSR-88D AT 01Z SHOWED SOME ISOLATED CONVECTION DROPPING SOUTH ACROSS EASTERN PORTIONS OF FORECAST AREA. THIS EVENING 00Z RNK SOUNDING SHOWED THE DRIER AIR PUSHING AROUND 700 MB WITH A NORTHERLY FLOW AND PWAT AT 0.46 IN. THE NAM...HRRR...RNK WRFARW AND HIRESW-ARW SUPPORT THE MENTION OF ISOLATED SHOWERS TONIGHT UNTIL AROUND 06Z...MAINLY EAST OF THE BLUE RIDGE MOUNTAINS. PATCHES OF FOG WILL DEVELOP OVERNIGHT ESPECIALLY WHERE IT RAIN FRIDAY. LOW TEMPERATURES OVERNIGHT WILL RANGE FROM AROUND 40 DEGREES IN THE NORTHWEST MOUNTAINS TO THE MID TO UPPER 40S IN THE PIEDMONT. HAVE A GOOD NIGHT. AS OF 555 PM EDT FRIDAY... ADJUSTED TEMPERATURES DOWN IN RAIN COOLED LOCATIONS AND BLEND LAMP TEMPERATURES INTO THE OVERNIGHT. MODIFIED POPS AND WEATHER WITH LATEST WSR-88D TRENDS AND SHAPED POPS THIS EVENING INTO TONIGHT TOWARDS A BLEND OF THE HRRR AND THE RNK WRFARW. AS THE UPPER LOW PUSHES EAST...AREAL COVERAGE OF CONVECTION WILL DIMINISH AND EXIT THE REGION. PATCHES OF FOG WILL DEVELOP ESPECIALLY WHERE IT RAIN THIS AFTERNOON AND THIS EVENING AND CONTINUE INTO THE OVERNIGHT. HELD ON TO THE THE OVERNIGHT LOW TEMPERATURES FROM AROUND 40 DEGREES IN THE NORTHWEST MOUNTAINS TO THE UPPER 40S IN THE PIEDMONT. AS OF 300 PM EDT FRIDAY... AN AREA OF SHOWERS WITH A FEW THUNDERSTORMS CONTINUES TO EXPAND IN COVERAGE BETWEEN ROUGHLY HOT SPRINGS AND BLACKSBURG VA. THE PRECIPITATION WAS EXPANDING TOWARDS THE S-SW. HEADING INTO THIS EVENING...THE REGION OF PRECIPITATION WILL GRADUALLY MAKE PROGRESS EASTWARD...IN PACE WITH THE PROGRESSION OF THE RESPONSIBLE UPPER LEVEL LOW PRESSURE SYSTEM. COVERAGE WILL START TO DECREASE AT SUNSET...WITH THE LAST SHOWERS EXITING THE AREA OR DISSIPATING AROUND 11PM BETWEEN DANVILLE AND LYNCHBURG. CLOUD COVER WILL BE ON THE DECREASE THE REMAINDER OF THE NIGHT. PATCHY LIGHT RIVER VALLEY FOG WILL BE POSSIBLE...AND ALSO IN VALLEYS THAT RECEIVED PRECIPITATION THIS AFTERNOON OR EVENING. LOW TEMPERATURES WILL RANGE FROM AROUND 40 TO THE MID 40S ACROSS THE MOUNTAINS...WITH MID 40S TO UPPER 40S ACROSS THE PIEDMONT. ON SATURDAY...HIGH PRESSURE WILL START TO WORK ITS WAY INTO THE REGION FROM THE WEST. ONE LATE SHORTWAVE TROUGH ROUNDING THE BACKSIDE OF THE DEPARTING UPPER LOW IS EXPECTED TO MOVE SOUTH THROUGH CENTRAL VIRGINIA AND NORTH CAROLINA TOMORROW AFTERNOON. THIS FEATURE PASSING AT THE TIME OF PEAK HEATING MAY HELP TO GENERATE SOME ISOLATED SHOWERS...GENERALLY ALONG AND EAST OF A LEXINGTON VA TO REIDSVILLE NORTH CAROLINA LINE. THANKS TO BUILDING HEIGHTS AND LESS CLOUD COVER...ANTICIPATE A MILDER DAY ON SATURDAY AS COMPARED TO TODAY. HIGHS ACROSS THE MOUNTAINS WILL RANGE FROM THE MID 60S TO NEAR 70 DEGREES...WITH LOW TO MID 70S ACROSS THE PIEDMONT. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/... AS OF 315 PM EDT FRIDAY... 500 MB HEIGHTS GRADUALLY RISE SATURDAY NIGHT AND SUNDAY AS THE PATTERN BECOMES MORE ZONAL. BUFKIT DATA FOR SUNDAY IN THE SOUTHWEST COUNTY WARNING AREA SHOWED A LARGE ENOUGH LOW LEVEL LAPSE RATE AND A LAYER OF MOISTURE THAT WOULD SUPPORT SHOWERS ISOLATED THUNDERSTORMS. HOWEVER...THERE WILL ONLY BE MINIMAL LIFT FROM ANY VORTICITY SO COVERAGE WILL BE CONFINED TO AREAS WITH THE BEST HEATING AND INSTABILITY. AIR MASS WARMS THROUGH THE PERIOD AND WILL BE CLOSE TO +10 TO +12 VALUES AT 850 MB BY THE END OF THE DAY ON MONDAY. THIS WILL PUT MAXIMUM TEMPERATURES JUST ABOVE NORMAL MONDAY. HIGH PRESSURE WILL BE OVER THE AREA SATURDAY NIGHT AND SUNDAY. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 125 PM EDT FRIDAY... LONG WAVE PATTERN ADVERTISED BY MODELS SHOWED TROFING IN THE WESTERN UNITED STATES AND A BROAD SOUTHEAST U.S. RIDGE. A SURFACE COLD FRONT THE THE NORTHERN STREAM WILL BE OVER THE GREAT LAKES ON MONDAY AND WILL PUSH SOUTH AS A BACKDOOR FRONT OVER THE MID ATLANTIC REGION TUESDAY AND WEDNESDAY. QUESTIONABLE HOW FAR SOUTH THIS BOUNDARY GETS HEADING INTO A LARGE RIDGE OVER THE SOUTHEAST. BEST PROBABILITY OF PRECIPITATION WILL BE IN THE VICINITY OF THIS BOUNDARY. OTHERWISE THE CHANCE WILL BE LIMITED TO AIRMASS TYPE THUNDERSTORMS...MAINLY IN THE MOUNTAINS EACH AFTERNOON AND EVENING. MAXIMUM/MINIMUM TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE NORMAL TUESDAY THROUGH FRIDAY. && .AVIATION /01Z SATURDAY THROUGH WEDNESDAY/... AS OF 745 PM EDT FRIDAY... IMPROVING AVIATION CONDITIONS EXPECTED THIS TAF VALID PERIOD. PESKY UPPER LOW CENTERED NEAR ORF WILL DRIFT FURTHER OUT TO SEA OVERNIGHT AND SATURDAY. A BROAD RIDGE OF HIGH PRESSURE WILL BUILD EAST FROM THE OH/TN VALLEY FOR THE WEEKEND. HOWEVER...THE LAST FEW LOBES OF PVA WILL ROTATE AROUND THE BACK SIDE OF THE UPPER LOW AND WILL CONTINUE TO SUPPORT A FEW SHOWERS MAINLY EAST OF THE BLUE RIDGE OVERNIGHT. NOT TOTALLY CONVINCED THAT THERE MIGHT NOT BE ONE OR TWO SHOWER ACROSS THE FAR EASTERN PIEDMONT SATURDAY AFTERNOON DURING MAX HEATING AS THE LAST VESTIGES OF THE UPPER LOW LINGER IN THAT REGION...BUT WITH THE POSSIBLE EXCEPTION OF LYH...THIS SHOULD REMAIN EAST OF THE TAF VALID SITES. CIGS/VSBYS ARE VFR AT THE CURRENT TIME...EXCEPT FOR KDAN...WHERE AN AREA OF SHRA...WITH SOME +SHRA...WILL DRIFT THROUGH OVER THE NEXT HOUR. ONE CONCERN OVERNIGHT IS FOG POTENTIAL...AND THEN LOW CLOUDS ACROSS EASTERN WV. WITH MOIST GROUND FROM RAINFALL THIS AFTERNOON...AM CONCERNED THAT FOG WILL GROUND FOG WILL DEVELOP IN SOME AREAS OVERNIGHT...INCLUDING LYH/DAN/LWB/BCB. LESS CONVINCED THAT SUCH WILL OCCUR AT ROA. BUFKIT SHOWS GOOD POTENTIAL FOR FOG DEVELOPMENT AT LYH AND DAN. NEGATING EFFECT WOULD BE A LIGHT NW BREEZE...BUT DO NOT FEEL THIS WILL BE ENOUGH TO PRECLUDE FOG DEVELOPMENT ACROSS THE PIEDMONT. HAVE LOWERED VISIBILITIES TO IFR IN BR AT LYH/BCB/LWB IN THE 08Z-12Z TIME FRAME. AFTER 14Z SAT...EXPECT VFR CONDITIONS AREA WIDE...WITH JUST SOME BKN LOW END VFR CIGS ACROSS THE PIEDMONT DURING PEAK HEATING. WINDS LIGHT AND MOSTLY NW THROUGH THE TAF VALID PERIOD ON THE BACK SIDE OF THE UPPER LOW...BUT SOME VARIABLE WINDS THIS EVENING. AT ANY RATE...SPEEDS MOSTLY 7KTS OR LESS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGH 14Z...THEN HIGH CONFIDENCE IN VFR VSBYS AT ALL TAF SITES. MEDIUM CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD. NOTE...THE VISIBILITY SENSOR AT THE ASOS AT KBLF CONTINUES TO MALFUNCTION. WILL CONTINUE WITH AMD NOT SKED APPENDED TO ITS TAF. EXTENDED AVIATION DISCUSSION... OTHER THAN SOME PATCHY LATE NIGHT/EARLY MORNING RIVER VALLEY FOG IN THE TYPICAL LOCATIONS...VFR CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. SCATTERED AFTERNOON SHOWERS COULD AFFECT THE MOUNTAINS TUE...BUT MORE LIKELY WED-THU AS A BACK DOOR FRONT DRIFTS TOWARD THE REGION. HIGH PRESSURE ALOFT WILL NOT PROVIDE MUCH IN THE WAY OF ANY SYNOPTIC-SCALE FORCING THROUGH THE PERIOD THOUGH. && .EQUIPMENT... AS OF 907 PM EDT FRIDAY... THE VISIBILITY SENSOR AT THE BLUEFIELD...KBLF...ASOS MAY ALTERNATE BETWEEN AVAILABLE AND UNAVAILABLE UNTIL SUCH TIME APPROPRIATE CORRECTIVE MEASURES CAN BE COMPLETED. THE NOAA WEATHER RADIO AT ROANOKE VIRGINIA...WXL60...WHICH BROADCASTS AT A FREQUENCY OF 162.475 MHZ...IS BACK ON THE AIR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/KK SHORT TERM...AMS/RAB LONG TERM...AMS AVIATION...DS EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
754 PM EDT FRI MAY 1 2015 .SYNOPSIS... AN UPPER LEVEL LOW PRESSURE SYSTEM WILL PROGRESS EASTWARD...OUT OF THE REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND AND BE POSITIONED ACROSS OUR REGION INTO MUCH OF NEXT WEEK. OUR NEXT BEST CHANCE OF PRECIPITATION WILL COME DURING THE MIDDLE OF NEXT WEEK WHEN A BACKDOOR COLD FRONT APPROACHES OUR AREA. && .NEAR TERM /THROUGH SATURDAY/... AS OF 555 PM EDT FRIDAY... ADJUSTED TEMPERATURES DOWN IN RAIN COOLED LOCATIONS AND BLEND LAMP TEMPERATURES INTO THE OVERNIGHT. MODIFIED POPS AND WEATHER WITH LATEST WSR-88D TRENDS AND SHAPED POPS THIS EVENING INTO TONIGHT TOWARDS A BLEND OF THE HRRR AND THE RNK WRFARW. AS THE UPPER LOW PUSHES EAST...AREAL COVERAGE OF CONVECTION WILL DIMINISH AND EXIT THE REGION. PATCHES OF FOG WILL DEVELOP ESPECIALLY WHERE IT RAIN THIS AFTERNOON AND THIS EVENING AND CONTINUE INTO THE OVERNIGHT. HELD ON TO THE THE OVERNIGHT LOW TEMPERATURES FROM AROUND 40 DEGREES IN THE NORTHWEST MOUNTAINS TO THE UPPER 40S IN THE PIEDMONT. AS OF 300 PM EDT FRIDAY... AN AREA OF SHOWERS WITH A FEW THUNDERSTORMS CONTINUES TO EXPAND IN COVERAGE BETWEEN ROUGHLY HOT SPRINGS AND BLACKSBURG VA. THE PRECIPITATION WAS EXPANDING TOWARDS THE S-SW. HEADING INTO THIS EVENING...THE REGION OF PRECIPITATION WILL GRADUALLY MAKE PROGRESS EASTWARD...IN PACE WITH THE PROGRESSION OF THE RESPONSIBLE UPPER LEVEL LOW PRESSURE SYSTEM. COVERAGE WILL START TO DECREASE AT SUNSET...WITH THE LAST SHOWERS EXITING THE AREA OR DISSIPATING AROUND 11PM BETWEEN DANVILLE AND LYNCHBURG. CLOUD COVER WILL BE ON THE DECREASE THE REMAINDER OF THE NIGHT. PATCHY LIGHT RIVER VALLEY FOG WILL BE POSSIBLE...AND ALSO IN VALLEYS THAT RECEIVED PRECIPITATION THIS AFTERNOON OR EVENING. LOW TEMPERATURES WILL RANGE FROM AROUND 40 TO THE MID 40S ACROSS THE MOUNTAINS...WITH MID 40S TO UPPER 40S ACROSS THE PIEDMONT. ON SATURDAY...HIGH PRESSURE WILL START TO WORK ITS WAY INTO THE REGION FROM THE WEST. ONE LATE SHORTWAVE TROUGH ROUNDING THE BACKSIDE OF THE DEPARTING UPPER LOW IS EXPECTED TO MOVE SOUTH THROUGH CENTRAL VIRGINIA AND NORTH CAROLINA TOMORROW AFTERNOON. THIS FEATURE PASSING AT THE TIME OF PEAK HEATING MAY HELP TO GENERATE SOME ISOLATED SHOWERS...GENERALLY ALONG AND EAST OF A LEXINGTON VA TO REIDSVILLE NORTH CAROLINA LINE. THANKS TO BUILDING HEIGHTS AND LESS CLOUD COVER...ANTICIPATE A MILDER DAY ON SATURDAY AS COMPARED TO TODAY. HIGHS ACROSS THE MOUNTAINS WILL RANGE FROM THE MID 60S TO NEAR 70 DEGREES...WITH LOW TO MID 70S ACROSS THE PIEDMONT. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/... AS OF 315 PM EDT FRIDAY... 500 MB HEIGHTS GRADUALLY RISE SATURDAY NIGHT AND SUNDAY AS THE PATTERN BECOMES MORE ZONAL. BUFKIT DATA FOR SUNDAY IN THE SOUTHWEST COUNTY WARNING AREA SHOWED A LARGE ENOUGH LOW LEVEL LAPSE RATE AND A LAYER OF MOISTURE THAT WOULD SUPPORT SHOWERS ISOLATED THUNDERSTORMS. HOWEVER...THERE WILL ONLY BE MINIMAL LIFT FROM ANY VORTICITY SO COVERAGE WILL BE CONFINED TO AREAS WITH THE BEST HEATING AND INSTABILITY. AIR MASS WARMS THROUGH THE PERIOD AND WILL BE CLOSE TO +10 TO +12 VALUES AT 850 MB BY THE END OF THE DAY ON MONDAY. THIS WILL PUT MAXIMUM TEMPERATURES JUST ABOVE NORMAL MONDAY. HIGH PRESSURE WILL BE OVER THE AREA SATURDAY NIGHT AND SUNDAY. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 125 PM EDT FRIDAY... LONG WAVE PATTERN ADVERTISED BY MODELS SHOWED TROFING IN THE WESTERN UNITED STATES AND A BROAD SOUTHEAST U.S. RIDGE. A SURFACE COLD FRONT THE THE NORTHERN STREAM WILL BE OVER THE GREAT LAKES ON MONDAY AND WILL PUSH SOUTH AS A BACKDOOR FRONT OVER THE MID ATLANTIC REGION TUESDAY AND WEDNESDAY. QUESTIONABLE HOW FAR SOUTH THIS BOUNDARY GETS HEADING INTO A LARGE RIDGE OVER THE SOUTHEAST. BEST PROBABILITY OF PRECIPITATION WILL BE IN THE VICINITY OF THIS BOUNDARY. OTHERWISE THE CHANCE WILL BE LIMITED TO AIRMASS TYPE THUNDERSTORMS...MAINLY IN THE MOUNTAINS EACH AFTERNOON AND EVENING. MAXIMUM/MINIMUM TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE NORMAL TUESDAY THROUGH FRIDAY. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... AS OF 745 PM EDT FRIDAY... IMPROVING AVIATION CONDITIONS EXPECTED THIS TAF VALID PERIOD. PESKY UPPER LOW CENTERED NEAR ORF WILL DRIFT FURTHER OUT TO SEA OVERNIGHT AND SATURDAY. A BROAD RIDGE OF HIGH PRESSURE WILL BUILD EAST FROM THE OH/TN VALLEY FOR THE WEEKEND. HOWEVER...THE LAST FEW LOBES OF PVA WILL ROTATE AROUND THE BACK SIDE OF THE UPPER LOW AND WILL CONTINUE TO SUPPORT A FEW SHOWERS MAINLY EAST OF THE BLUE RIDGE OVERNIGHT. NOT TOTALLY CONVINCED THAT THERE MIGHT NOT BE ONE OR TWO SHOWER ACROSS THE FAR EASTERN PIEDMONT SATURDAY AFTERNOON DURING MAX HEATING AS THE LAST VESTIGES OF THE UPPER LOW LINGER IN THAT REGION...BUT WITH THE POSSIBLE EXCEPTION OF LYH...THIS SHOULD REMAIN EAST OF THE TAF VALID SITES. CIGS/VSBYS ARE VFR AT THE CURRENT TIME...EXCEPT FOR KDAN...WHERE AN AREA OF SHRA...WITH SOME +SHRA...WILL DRIFT THROUGH OVER THE NEXT HOUR. ONE CONCERN OVERNIGHT IS FOG POTENTIAL...AND THEN LOW CLOUDS ACROSS EASTERN WV. WITH MOIST GROUND FROM RAINFALL THIS AFTERNOON...AM CONCERNED THAT FOG WILL GROUND FOG WILL DEVELOP IN SOME AREAS OVERNIGHT...INCLUDING LYH/DAN/LWB/BCB. LESS CONVINCED THAT SUCH WILL OCCUR AT ROA. BUFKIT SHOWS GOOD POTENTIAL FOR FOG DEVELOPMENT AT LYH AND DAN. NEGATING EFFECT WOULD BE A LIGHT NW BREEZE...BUT DO NOT FEEL THIS WILL BE ENOUGH TO PRECLUDE FOG DEVELOPMENT ACROSS THE PIEDMONT. HAVE LOWERED VISIBILITIES TO IFR IN BR AT LYH/BCB/LWB IN THE 08Z-12Z TIME FRAME. AFTER 14Z SAT...EXPECT VFR CONDITIONS AREA WIDE...WITH JUST SOME BKN LOW END VFR CIGS ACROSS THE PIEDMONT DURING PEAK HEATING. WINDS LIGHT AND MOSTLY NW THROUGH THE TAF VALID PERIOD ON THE BACK SIDE OF THE UPPER LOW...BUT SOME VARIABLE WINDS THIS EVENING. AT ANY RATE...SPEEDS MOSTLY 7KTS OR LESS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGH 14Z...THEN HIGH CONFIDENCE IN VFR VSBYS AT ALL TAF SITES. MEDIUM CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD. NOTE...THE VISIBILITY SENSOR AT THE ASOS AT KBLF CONTINUES TO MALFUNCTION. WILL CONTINUE WITH AMD NOT SKED APPENDED TO ITS TAF. EXTENDED AVIATION DISCUSSION... OTHER THAN SOME PATCHY LATE NIGHT/EARLY MORNING RIVER VALLEY FOG IN THE TYPICAL LOCATIONS...VFR CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. SCATTERED AFTERNOON SHOWERS COULD AFFECT THE MOUNTAINS TUE...BUT MORE LIKELY WED-THU AS A BACK DOOR FRONT DRIFTS TOWARD THE REGION. HIGH PRESSURE ALOFT WILL NOT PROVIDE MUCH IN THE WAY OF ANY SYNOPTIC-SCALE FORCING THROUGH THE PERIOD THOUGH. && .EQUIPMENT... AS OF 330 PM EDT FRIDAY... THE VISIBILITY SENSOR AT THE BLUEFIELD...KBLF...ASOS MAY ALTERNATE BETWEEN AVAILABLE AND UNAVAILABLE UNTIL SUCH TIME APPROPRIATE CORRECTIVE MEASURES CAN BE COMPLETED. THE NOAA WEATHER RADIO AT ROANOKE VIRGINIA...WXL60...WHICH BROADCASTS AT A FREQUENCY OF 162.475 MHZ...IS BACK ON THE AIR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/KK SHORT TERM...AMS/RAB LONG TERM...AMS AVIATION...DS EQUIPMENT...DS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1050 AM CDT THU APR 30 2015 .UPDATE... DEEP 500 MB LOW PUSHING SOUTH ACROSS LAKE MICHIGAN HAS BROUGHT OVERCAST SKIES AND A FEW SPRINKLES TO EASTERN WISCONSIN. THE LOW SHOULD FINALLY MOVE OUT OF THE AREA THIS AFTERNOON...ALLOWING THE SKIES TO SCATTER OUT RESULTING IN A VERY PLEASANT AFTERNOON AND EVENING. WE ENDED UP ADJUSTING TEMPS UP A FEW DEGREES IN OUR WEST WHERE MOSTLY CLEAR TO CLEAR SKIES ARE EXPECTED THROUGH THE DAY. OTHERWISE LEFT TO FORECAST AS IS. && .AVIATION/18Z TAFS/... A DEEP MID-LEVEL LOW HAS BROUGHT MVFR CIGS TO MKE...ENW...AND UES. CONDITIONS SHOULD RAPIDLY IMPROVE THIS AFTERNOON AS THE LOW FINALLY MOVES OUT OF THE FORECAST AREA...ALLOWING SKIES TO SCATTER OUT. SKIES SHOULD REMAIN MOSTLY CLEAR OVERNIGHT AND REMAIN MOSTLY CLEAR THROUGH AROUND NOON. TOMORROW AFTERNOON...A MID-LEVEL SHORTWAVE WILL APPROACH THE STATE BRINGING SOME SCATTERED CLOUDS INTO SE WI. && .PREV DISCUSSION... /ISSUED 338 AM CDT THU APR 30 2015/ TODAY...FORECAST CONFIDENCE HIGH SURFACE HIGH PRESSURE BUILDS DOWN OVER WISCONSIN TODAY INTO TONIGHT AS MID-UPPER LEVEL CLOSED LOW NEAR THE LOWER MICHIGAN/INDIANA BORDER AT 12Z DROPS SE THROUGH THE DAY. AREA REMAINS UNDER CYCLONIC FLOW THROUGH MOST OF THE THE DAY. SATELLITE IMAGERY BRINGING SOME BROKEN CUMULUS DOWN THE LAKE AND EASTERN WISCONSIN WITH INSTABILITY AS 850-925 MB COLD POOLS ROTATE OVER THE STATE THIS MORNING...MAINLY OVER THE EASTERN HALF OF THE CWA. HRRR ALONE AMONG THE HI-RES/RAPID UPDATED MODELS IN SHOWING SPOTTY LIGHT QPF OVER THE EAST BETWEEN 14Z AND 18Z. HAVE PUT ISOLATED SPRINKLES OVER THE EAST THIS MORNING. EXPECT GUSTY NORTH WINDS...ESPECIALLY IN THE EAST...WITH MIXING UP TO 20 TO 30 KNOT WINDS WITH WINDS EASING THROUGH THE AFTERNOON. CLOUDS AND NORTHERLY WINDS WILL KEEP THE EAST COOL...WITH HIGHS AROUND 50 ALONG THE LAKE AND NEAR 60 INLAND...WHILE A BIT MORE SUN WILL ALLOW HIGHS IN THE MID 60S IN THE WEST. TONIGHT...FORECAST CONFIDENCE HIGH HIGH PRESSURE FIRMLY SETTLES OVER THE STATE WITH AMPLIFIED BUT NARROW MID-LEVEL RIDGE PUSHING INTO THE REGION OVERNIGHT. MADE A DOWNWARD TWEAK TO CONSENSUS LOWS WITH CLEARING SKIES AND LIGHT WINDS. FRIDAY AND SATURDAY...FORECAST CONFIDENCE...MEDIUM IT LOOKS MAINLY DRY FRIDAY AND SATURDAY AS HIGH PRESSURE SLIDES FROM OVERHEAD FRIDAY MORNING TO SOUTHEAST OF THE AREA SATURDAY. A FEW SHOWERS ARE NOT OUT OF THE QUESTION FRIDAY AFTERNOON INTO SATURDAY AS THE HIGH DEPARTS...BUT NOT SEEING ENOUGH MOISTURE AND ORGANIZED LIFT TO CONSIDER POPS MOST AREAS. ABOVE NORMAL TEMPERATURES ARE EXPECTED BOTH FRIDAY AND SATURDAY. A LAKE BREEZE IS LIKELY FRIDAY...SO EXPECT COOLER TEMPS NEAR THE LAKE. SOUTHWEST WINDS SHOULD BE STRONG ENOUGH SATURDAY TO PUSH THE MILDER TEMPS ALL THE WAY TO THE LAKE. THE EXCEPTION MAY BE NORTH OF MILWAUKEE...WHERE THE WINDS MAY BE MORE SOUTHERLY AND BRING IN SOME COOLER LAKE AIR ALONG SHORE...ESPECIALLY TOWARD SHEBOYGAN. SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE...MEDIUM MODELS ARE STILL POINTING TO A PROLONGED PERIOD OF WET WEATHER BEGINNING ON SUNDAY. SOUTHERLY LOW LEVEL FLOW WILL BRING WARM AND UNSTABLE CONDITIONS FOR SUNDAY...WITH A SHORTWAVE EXPECTED TO KICK OFF SHOWERS AND STORMS. COULD SEE A FEW STRONGER STORMS IN THE AFTERNOON AND EVENING...PARTICULARLY IN THE WESTERN FORECAST AREA WHERE THERE IS EXPECTED TO BE A BETTER COMBINATION OF SHEAR AND INSTABILITY. MORE SHOWERS/STORMS ARE POSSIBLE SUNDAY NIGHT INTO MONDAY AS A COLD FRONT DROPS SOUTHWARD THROUGH THE FORECAST AREA. THE FRONT IS PROGGED TO STALL JUST SOUTH OF THE STATE FOR TUESDAY...BRINGING A CHANCE FOR MORE ROUNDS OF SHOWERS AND STORMS. MODELS THEN BRING THE FRONT BACK NORTHWARD WEDNESDAY...RESULTING IN MORE STORM CHANCES. WELL ABOVE NORMAL TEMPS WILL LIKELY CONTINUE THROUGH MONDAY...WITH HIGHS COOLING BACK TO AROUND NORMAL VALUES TUESDAY BEHIND THE COLD FRONT. TEMPS WILL THEN LIKELY WARM BACK UP WEDNESDAY IF THE FRONT DOES INDEED LIFT NORTHWARD INTO/THROUGH THE FORECAST AREA. AVIATION/12Z TAFS/... EXPECT CLOUDS OVER THE EASTERN CWA THIS MORNING TO REMAIN AT VFR LEVELS...THOUGH SOME INDICATION OF A SHORT PERIOD OF A BROKEN MVFR CLOUD DECK THAT WOULD AFFECT THE LAKESHORE COUNTIES MID-LATE MORNING. COULD ALSO SEE A FEW SPRINKLES AS WELL BUT VERY ISOLATED AND TOO FEW TO MENTION IN THE EASTERN TAFS. NORTH-NORTHEAST WINDS WILL BE GUSTY AS WELL WITH MIXING UP TO 20-30 KNOT WINDS BRINGING SOME NEAR 20 KNOT GUSTS TO THE SURFACE. WINDS WILL EASE THROUGH THE AFTERNOON. VFR FOR THE REMAINDER OF THE FORECAST AS HIGH PRESSURE BUILDS IN. MARINE...ISSUED A SMALL CRAFT ADVISORY FOR THE SOUTHERN-MOST MARINE ZONES AS NORTHERLY WIND GUSTS HAVE BEEN RISING TO 22-25 KNOTS WITH TIGHTER GRADIENT THAN EXPECTED OVER THE SOUTHERN WATERS OF LAKE MICHIGAN. WILL CARRY IT UNTIL 7 PM...BUT WILL PROBABLY NOT NEED TO GO THAT LONG AS WINDS EASE THROUGH THE AFTERNOON. BOATERS IN THE REST OF THE NEARSHORE WATERS SHOULD EXERCISE CAUTION AS WINDS WILL GUST TO 20 KNOTS AT TIMES THROUGH THE MORNING. FIRE WEATHER... IT WILL BE DRY INTO THE WEEKEND WITH MINIMUM RELATIVE HUMIDITY VALUES SOMEWHAT ON THE LOW SIDE TODAY AND FRIDAY...IN THE 30-40 PERCENT RANGE...BEFORE RISING ABOVE 40 PERCENT FOR THE WEEKEND AND BEGINNING OF NEXT WEEK. EXPECT SOME GUSTY NORTH WINDS...ESPECIALLY THIS MORNING...WITH THE WINDS SLOWLY EASING THROUGH THE AFTERNOON. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ646. && $$ UPDATE...BSH TODAY/TONIGHT AND AVIATION/MARINE...REM FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
338 AM CDT THU APR 30 2015 .TODAY...FORECAST CONFIDENCE HIGH SURFACE HIGH PRESSURE BUILDS DOWN OVER WISCONSIN TODAY INTO TONIGHT AS MID-UPPER LEVEL CLOSED LOW NEAR THE LOWER MICHIGAN/INDIANA BORDER AT 12Z DROPS SE THROUGH THE DAY. AREA REMAINS UNDER CYCLONIC FLOW THROUGH MOST OF THE THE DAY. SATELLITE IMAGERY BRINGING SOME BROKEN CUMULUS DOWN THE LAKE AND EASTERN WISCONSIN WITH INSTABILITY AS 850-925 MB COLD POOLS ROTATE OVER THE STATE THIS MORNING...MAINLY OVER THE EASTERN HALF OF THE CWA. HRRR ALONE AMONG THE HI-RES/RAPID UPDATED MODELS IN SHOWING SPOTTY LIGHT QPF OVER THE EAST BETWEEN 14Z AND 18Z. HAVE PUT ISOLATED SPRINKLES OVER THE EAST THIS MORNING. EXPECT GUSTY NORTH WINDS...ESPECIALLY IN THE EAST...WITH MIXING UP TO 20 TO 30 KNOT WINDS WITH WINDS EASING THROUGH THE AFTERNOON. CLOUDS AND NORTHERLY WINDS WILL KEEP THE EAST COOL...WITH HIGHS AROUND 50 ALONG THE LAKE AND NEAR 60 INLAND...WHILE A BIT MORE SUN WILL ALLOW HIGHS IN THE MID 60S IN THE WEST. .TONIGHT...FORECAST CONFIDENCE HIGH HIGH PRESSURE FIRMLY SETTLES OVER THE STATE WITH AMPLIFIED BUT NARROW MID-LEVEL RIDGE PUSHING INTO THE REGION OVERNIGHT. MADE A DOWNWARD TWEAK TO CONSENSUS LOWS WITH CLEARING SKIES AND LIGHT WINDS. .FRIDAY AND SATURDAY...FORECAST CONFIDENCE...MEDIUM IT LOOKS MAINLY DRY FRIDAY AND SATURDAY AS HIGH PRESSURE SLIDES FROM OVERHEAD FRIDAY MORNING TO SOUTHEAST OF THE AREA SATURDAY. A FEW SHOWERS ARE NOT OUT OF THE QUESTION FRIDAY AFTERNOON INTO SATURDAY AS THE HIGH DEPARTS...BUT NOT SEEING ENOUGH MOISTURE AND ORGANIZED LIFT TO CONSIDER POPS MOST AREAS. ABOVE NORMAL TEMPERATURES ARE EXPECTED BOTH FRIDAY AND SATURDAY. A LAKE BREEZE IS LIKELY FRIDAY...SO EXPECT COOLER TEMPS NEAR THE LAKE. SOUTHWEST WINDS SHOULD BE STRONG ENOUGH SATURDAY TO PUSH THE MILDER TEMPS ALL THE WAY TO THE LAKE. THE EXCEPTION MAY BE NORTH OF MILWAUKEE...WHERE THE WINDS MAY BE MORE SOUTHERLY AND BRING IN SOME COOLER LAKE AIR ALONG SHORE...ESPECIALLY TOWARD SHEBOYGAN. .SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE...MEDIUM MODELS ARE STILL POINTING TO A PROLONGED PERIOD OF WET WEATHER BEGINNING ON SUNDAY. SOUTHERLY LOW LEVEL FLOW WILL BRING WARM AND UNSTABLE CONDITIONS FOR SUNDAY...WITH A SHORTWAVE EXPECTED TO KICK OFF SHOWERS AND STORMS. COULD SEE A FEW STRONGER STORMS IN THE AFTERNOON AND EVENING...PARTICULARLY IN THE WESTERN FORECAST AREA WHERE THERE IS EXPECTED TO BE A BETTER COMBINATION OF SHEAR AND INSTABILITY. MORE SHOWERS/STORMS ARE POSSIBLE SUNDAY NIGHT INTO MONDAY AS A COLD FRONT DROPS SOUTHWARD THROUGH THE FORECAST AREA. THE FRONT IS PROGGED TO STALL JUST SOUTH OF THE STATE FOR TUESDAY...BRINGING A CHANCE FOR MORE ROUNDS OF SHOWERS AND STORMS. MODELS THEN BRING THE FRONT BACK NORTHWARD WEDNESDAY...RESULTING IN MORE STORM CHANCES. WELL ABOVE NORMAL TEMPS WILL LIKELY CONTINUE THROUGH MONDAY...WITH HIGHS COOLING BACK TO AROUND NORMAL VALUES TUESDAY BEHIND THE COLD FRONT. TEMPS WILL THEN LIKELY WARM BACK UP WEDNESDAY IF THE FRONT DOES INDEED LIFT NORTHWARD INTO/THROUGH THE FORECAST AREA. && .AVIATION/12Z TAFS/... EXPECT CLOUDS OVER THE EASTERN CWA THIS MORNING TO REMAIN AT VFR LEVELS...THOUGH SOME INDICATION OF A SHORT PERIOD OF A BROKEN MVFR CLOUD DECK THAT WOULD AFFECT THE LAKESHORE COUNTIES MID-LATE MORNING. COULD ALSO SEE A FEW SPRINKLES AS WELL BUT VERY ISOLATED AND TOO FEW TO MENTION IN THE EASTERN TAFS. NORTH-NORTHEAST WINDS WILL BE GUSTY AS WELL WITH MIXING UP TO 20-30 KNOT WINDS BRINGING SOME NEAR 20 KNOT GUSTS TO THE SURFACE. WINDS WILL EASE THROUGH THE AFTERNOON. VFR FOR THE REMAINDER OF THE FORECAST AS HIGH PRESSURE BUILDS IN. && .MARINE...ISSUED A SMALL CRAFT ADVISORY FOR THE SOUTHERN-MOST MARINE ZONES AS NORTHERLY WIND GUSTS HAVE BEEN RISING TO 22-25 KNOTS WITH TIGHTER GRADIENT THAN EXPECTED OVER THE SOUTHERN WATERS OF LAKE MICHIGAN. WILL CARRY IT UNTIL 7 PM...BUT WILL PROBABLY NOT NEED TO GO THAT LONG AS WINDS EASE THROUGH THE AFTERNOON. BOATERS IN THE REST OF THE NEARSHORE WATERS SHOULD EXERCISE CAUTION AS WINDS WILL GUST TO 20 KNOTS AT TIMES THROUGH THE MORNING. && .FIRE WEATHER... IT WILL BE DRY INTO THE WEEKEND WITH MINIMUM RELATIVE HUMIDITY VALUES SOMEWHAT ON THE LOW SIDE TODAY AND FRIDAY...IN THE 30-40 PERCENT RANGE...BEFORE RISING ABOVE 40 PERCENT FOR THE WEEKEND AND BEGINNING OF NEXT WEEK. EXPECT SOME GUSTY NORTH WINDS...ESPECIALLY THIS MORNING...WITH THE WINDS SLOWLY EASING THROUGH THE AFTERNOON. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ646. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1002 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 959 PM MDT FRI MAY 1 2015 WE HAVE ADDED AREAS OF DENSE FOG THROUGH AROUND 1 AM FOR THE INTERSTATE 80 SUMMIT BETWEEN LARAMIE AND CHEYENNE AS WELL AS OVER THE WESTERN FOOTHILLS OF LARAMIE COUNTY BASED ON WEBCAMS. WE BELIEVE THE FOG WILL QUICKLY DISSIPATE BETWEEN MIDNIGHT AND 3 AM AS THE BOUNDARY LAYER WINDS BECOME WEST. UPDATE ISSUED AT 932 PM MDT FRI MAY 1 2015 GRIDDED FORECASTS UPDATED TO REMOVE SHOWERS AND THUNDERSTORMS FOR THE REST OF THE NIGHT AND TO ADJUST TEMPERATURES...DEWPOINTS...WINDS AND CLOUD COVER FOR THE REST OF THE NIGHT. UPDATE ISSUED AT 602 PM MDT FRI MAY 1 2015 OUR GRIDDED FORECASTS HAVE BEEN UPDATED PRIMARILY TO ACCOUNT FOR SPATIAL COVERAGE OF SHOWERS AND THUNDERSTORMS...OVER EASTERN LARAMIE COUNTY OF WYOMING...AND OVER KIMBALL AND WESTERN CHEYENNE COUNTIES OF NEBRASKA. HAVE TOUCHED UP OTHER METEOROLOGICAL VARIABLES FOR THE REST OF THE NIGHT BASED ON TRENDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 354 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS ARE ON THE UPTICK ALONG THE INTERSTATE 80 CORRIDOR IN SOUTHEAST WY THIS AFTERNOON. AS EXPECTED...THE GREATEST COVERAGE HAS BEEN IN ALBANY IN LARAMIE COUNTIES WITH ENHANCED LOWER LEVEL CONVERGENCE ALONG THE LARAMIE RANGE. THE KCYS RADAR LOOP ALSO SHOWS NUMEROUS BOUNDARIES IN THE VICINITY OF CYS...LIKELY PLAYING A ROLE IN CONVECTIVE EVOLUTION. CLOUDS CLEARED LATE THIS AM...HELPING PUSH SFC TEMPS INTO THE 55-65 DEGREE RANGE AMID DECENT LLVL MOISTURE WITH DEWPOINTS IN THE MID 40S F. THIS BENEATH STEEP MID LEVEL LAPSE RATES ON THE ORDER OF 8-9 DEG C/KM IS CONTRIBUTING TO SBCAPES ON THE ORDER OF 1500 J/KG PER THE 21Z SPC MESOANALYSIS. GFS AND NAM BUFKIT SOUNDINGS BOTH SHOW H5 FLOW AROUND 30 KTS...WHICH COMBINED WITH GOOD VEERING IN THE SFC-500 MILLIBAR LAYER IS CONTRIBUTING TO EFFECTIVE BULK SHEAR VALUES FAVORABLE FOR ROTATING UPDRAFTS (35-45 KTS). COULD SEE A HAIL THREAT EVOLVE WITH SOME CELLS...BUT DO NOT EXPECT TO SEE MORE THAN ONE OR TWO SEVERE STORMS. OPTED TO MAINTAIN SMALL HAIL AND GUSTY WIND WORDING IN THE OFFICIAL FORECAST. LATEST HRRR HAS CHANGED VERY LITTLE FROM THIS MORNING...AND APPEARS TO BE ACCURATELY SHOWING CONVECTIVE ELEMENTS BETWEEN LARAMIE AND CHEYENNE. FOR THAT REASON... WILL MAINTAIN LIKELY POPS FOR THOSE AREAS. CONVECTIVE COVERAGE WILL DWINDLE OVERNIGHT WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. QUASI-ZONAL FLOW ALOFT PERSISTS INTO SATURDAY. A SERIES OF MID LEVEL DISTURBANCES WILL TRAVERSE THE FLOW OVER THE CENTRAL ROCKIES...ONCE AGAIN PROMOTING AFTERNOON CONVECTION CHANCES. THE DAY 2 SPC OUTLOOK HAS SHIFTED THE MARGINAL RISK EAST OF OUR CWA...WHICH MAKES SENSE AS THE LATEST IN-HOUSE WRF PLACES THE BEST INSTABILITY AXIS EAST OF AN ALLIANCE TO SIDNEY LINE BETWEEN 18-20Z SAT. POTENTIAL FOR WIDESPREAD THUNDERSTORMS WILL DEPEND ON THE TIMING OF THE DRYLINE. GFS AND NAM BOTH PUSH THIS FEATURE EAST OF THE CWA BY EARLY TO MID AFTERNOON... BUT MODELS TEND TO MIX DRYLINES A BIT QUICKLY. LATER SHIFTS MAY NEED TO ADJUST POPS ACCORDINGLY IF IT APPEARS THE LOW-LEVEL CONVERGENCE ZONE WILL HANG ANY FURTHER WEST. A MUCH WARMER DAY APPEARS TO BE ON TAP TOMORROW FOR THE PLAINS WITH WESTERLY DOWNSLOPE FLOW...AND 700 MILLIBAR TEMPS AROUND 8-10 DEG C. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 354 PM MDT FRI MAY 1 2015 THIS PERIOD WILL BE DOMINATED BY GENERALLY CONSISTENT SOUTHWEST FLOW ACROSS THE INTERMOUNTAIN WEST AS YET ANOTHER LARGE SCALE TROUGH IS CARVED INTO THE WRN CONUS. MOISTURE ADVECTION ALONG WITH DIFFICULT TO TIME SHORTWAVES EMBEDDED WITHIN THIS FLOW WILL SET THE STAGE FOR A RELATIVELY UNSETTLED PERIOD. THIS BEGINS ON SUNDAY/MONDAY AS WEAK SFC BOUNDARY SETTLES SOUTH ACROSS THE PLAINS HANGING UP AROUND THE FRONT RANGE. MEANWHILE...RELATIVELY WEAK SHORTWAVE ENERGY WILL LIFT ACROSS THIS BOUNDARY AND WHEN COMBINED WITH WEAK INSTABILITY PROGS (SBCAPE 300- 500 J/KG) WILL PRODUCE AFTERNOON/EVENING CONVECTION BOTH DAYS. A STRONGER EJECTING TROUGH WILL MOVE THROUGH THE CWFA TUE/WED. BUT WITH MORE MOISTURE AND THICKER CLOUD CANOPY...INSTABILITIES ARE PROGD TO BE LESS. SOUTHWEST FLOW PERSISTS INTO THURSDAY WITH THE NEXT TROUGH SWINGING OUT OF THE DEEPENING WEST COAST TROUGH FOR FRIDAY OR FRIDAY NIGHT...DEPENDING ON THE MEDIUM RANGE GUIDANCE OF CHOICE. ISOLATED TO SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS ARE HARD TO ARGUE WITH REALLY ANY DAY NEXT WEEK. SO HAVE KEPT PRECIP CHANCES FAIRLY BROAD BRUSH BUT NOT WIDESPREAD NEXT WEEK. SUNDAY WILL BE THE WARMEST DAY OF THE WEEK WITH HIGHS REACHING THE 60S/70S. HIGHS WILL FALL BACK INTO THE 60S GENERALLY MON-FRI. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 536 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS WILL DIE OFF ACROSS FAR SOUTHEAST WYOMING AND SOUTHERN NEBRASKA PANHANDLE OVER THE NEXT FEW HOURS. OTHER THAN LOCAL MVFR NEAR SHOWERS AND THUNDERSTORMS MAINLY LOOKING AT VFR THROUGH THE TAF PERIOD...ALTHOUGH PATCHY RADIATION FOG IS POSSIBLE LATE TONIGHT WITH LIGHT WINDS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON...SOME WITH GUSTY WINDS AND SMALL HAIL. && .FIRE WEATHER... ISSUED AT 354 PM MDT FRI MAY 1 2015 FIRE WEATHER CONCERNS WILL BE ON THE LOW SIDE WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. WHILE ANY GIVEN STORM MAY PRODUCE GUSTY AND ERRATIC WINDS...NO DRY LIGHTNING IS EXPECTED. AFTERNOON RELATIVE HUMIDITY VALUES SHOULD REMAIN ABOVE 15 PERCENT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...RUBIN SHORT TERM...CLH LONG TERM...CAH AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
937 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 932 PM MDT FRI MAY 1 2015 GRIDDED FORECASTS UPDATED TO REMOVE SHOWERS AND THUNDERSTORMS FOR THE REST OF THE NIGHT AND TO ADJUST TEMPERATURES...DEWPOINTS...WINDS AND CLOUD COVER FOR THE REST OF THE NIGHT. UPDATE ISSUED AT 602 PM MDT FRI MAY 1 2015 OUR GRIDDED FORECASTS HAVE BEEN UPDATED PRIMARILY TO ACCOUNT FOR SPATIAL COVERAGE OF SHOWERS AND THUNDERSTORMS...OVER EASTERN LARAMIE COUNTY OF WYOMING...AND OVER KIMBALL AND WESTERN CHEYENNE COUNTIES OF NEBRASKA. HAVE TOUCHED UP OTHER METEOROLOGICAL VARIABLES FOR THE REST OF THE NIGHT BASED ON TRENDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 354 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS ARE ON THE UPTICK ALONG THE INTERSTATE 80 CORRIDOR IN SOUTHEAST WY THIS AFTERNOON. AS EXPECTED...THE GREATEST COVERAGE HAS BEEN IN ALBANY IN LARAMIE COUNTIES WITH ENHANCED LOWER LEVEL CONVERGENCE ALONG THE LARAMIE RANGE. THE KCYS RADAR LOOP ALSO SHOWS NUMEROUS BOUNDARIES IN THE VICINITY OF CYS...LIKELY PLAYING A ROLE IN CONVECTIVE EVOLUTION. CLOUDS CLEARED LATE THIS AM...HELPING PUSH SFC TEMPS INTO THE 55-65 DEGREE RANGE AMID DECENT LLVL MOISTURE WITH DEWPOINTS IN THE MID 40S F. THIS BENEATH STEEP MID LEVEL LAPSE RATES ON THE ORDER OF 8-9 DEG C/KM IS CONTRIBUTING TO SBCAPES ON THE ORDER OF 1500 J/KG PER THE 21Z SPC MESOANALYSIS. GFS AND NAM BUFKIT SOUNDINGS BOTH SHOW H5 FLOW AROUND 30 KTS...WHICH COMBINED WITH GOOD VEERING IN THE SFC-500 MILLIBAR LAYER IS CONTRIBUTING TO EFFECTIVE BULK SHEAR VALUES FAVORABLE FOR ROTATING UPDRAFTS (35-45 KTS). COULD SEE A HAIL THREAT EVOLVE WITH SOME CELLS...BUT DO NOT EXPECT TO SEE MORE THAN ONE OR TWO SEVERE STORMS. OPTED TO MAINTAIN SMALL HAIL AND GUSTY WIND WORDING IN THE OFFICIAL FORECAST. LATEST HRRR HAS CHANGED VERY LITTLE FROM THIS MORNING...AND APPEARS TO BE ACCURATELY SHOWING CONVECTIVE ELEMENTS BETWEEN LARAMIE AND CHEYENNE. FOR THAT REASON... WILL MAINTAIN LIKELY POPS FOR THOSE AREAS. CONVECTIVE COVERAGE WILL DWINDLE OVERNIGHT WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. QUASI-ZONAL FLOW ALOFT PERSISTS INTO SATURDAY. A SERIES OF MID LEVEL DISTURBANCES WILL TRAVERSE THE FLOW OVER THE CENTRAL ROCKIES...ONCE AGAIN PROMOTING AFTERNOON CONVECTION CHANCES. THE DAY 2 SPC OUTLOOK HAS SHIFTED THE MARGINAL RISK EAST OF OUR CWA...WHICH MAKES SENSE AS THE LATEST IN-HOUSE WRF PLACES THE BEST INSTABILITY AXIS EAST OF AN ALLIANCE TO SIDNEY LINE BETWEEN 18-20Z SAT. POTENTIAL FOR WIDESPREAD THUNDERSTORMS WILL DEPEND ON THE TIMING OF THE DRYLINE. GFS AND NAM BOTH PUSH THIS FEATURE EAST OF THE CWA BY EARLY TO MID AFTERNOON... BUT MODELS TEND TO MIX DRYLINES A BIT QUICKLY. LATER SHIFTS MAY NEED TO ADJUST POPS ACCORDINGLY IF IT APPEARS THE LOW-LEVEL CONVERGENCE ZONE WILL HANG ANY FURTHER WEST. A MUCH WARMER DAY APPEARS TO BE ON TAP TOMORROW FOR THE PLAINS WITH WESTERLY DOWNSLOPE FLOW...AND 700 MILLIBAR TEMPS AROUND 8-10 DEG C. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 354 PM MDT FRI MAY 1 2015 THIS PERIOD WILL BE DOMINATED BY GENERALLY CONSISTENT SOUTHWEST FLOW ACROSS THE INTERMOUNTAIN WEST AS YET ANOTHER LARGE SCALE TROUGH IS CARVED INTO THE WRN CONUS. MOISTURE ADVECTION ALONG WITH DIFFICULT TO TIME SHORTWAVES EMBEDDED WITHIN THIS FLOW WILL SET THE STAGE FOR A RELATIVELY UNSETTLED PERIOD. THIS BEGINS ON SUNDAY/MONDAY AS WEAK SFC BOUNDARY SETTLES SOUTH ACROSS THE PLAINS HANGING UP AROUND THE FRONT RANGE. MEANWHILE...RELATIVELY WEAK SHORTWAVE ENERGY WILL LIFT ACROSS THIS BOUNDARY AND WHEN COMBINED WITH WEAK INSTABILITY PROGS (SBCAPE 300- 500 J/KG) WILL PRODUCE AFTERNOON/EVENING CONVECTION BOTH DAYS. A STRONGER EJECTING TROUGH WILL MOVE THROUGH THE CWFA TUE/WED. BUT WITH MORE MOISTURE AND THICKER CLOUD CANOPY...INSTABILITIES ARE PROGD TO BE LESS. SOUTHWEST FLOW PERSISTS INTO THURSDAY WITH THE NEXT TROUGH SWINGING OUT OF THE DEEPENING WEST COAST TROUGH FOR FRIDAY OR FRIDAY NIGHT...DEPENDING ON THE MEDIUM RANGE GUIDANCE OF CHOICE. ISOLATED TO SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS ARE HARD TO ARGUE WITH REALLY ANY DAY NEXT WEEK. SO HAVE KEPT PRECIP CHANCES FAIRLY BROAD BRUSH BUT NOT WIDESPREAD NEXT WEEK. SUNDAY WILL BE THE WARMEST DAY OF THE WEEK WITH HIGHS REACHING THE 60S/70S. HIGHS WILL FALL BACK INTO THE 60S GENERALLY MON-FRI. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 536 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS WILL DIE OFF ACROSS FAR SOUTHEAST WYOMING AND SOUTHERN NEBRASKA PANHANDLE OVER THE NEXT FEW HOURS. OTHER THAN LOCAL MVFR NEAR SHOWERS AND THUNDERSTORMS MAINLY LOOKING AT VFR THROUGH THE TAF PERIOD...ALTHOUGH PATCHY RADIATION FOG IS POSSIBLE LATE TONIGHT WITH LIGHT WINDS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON...SOME WITH GUSTY WINDS AND SMALL HAIL. && .FIRE WEATHER... ISSUED AT 354 PM MDT FRI MAY 1 2015 FIRE WEATHER CONCERNS WILL BE ON THE LOW SIDE WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. WHILE ANY GIVEN STORM MAY PRODUCE GUSTY AND ERRATIC WINDS...NO DRY LIGHTNING IS EXPECTED. AFTERNOON RELATIVE HUMIDITY VALUES SHOULD REMAIN ABOVE 15 PERCENT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...RUBIN SHORT TERM...CLH LONG TERM...CAH AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
605 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 602 PM MDT FRI MAY 1 2015 OUR GRIDDED FORECASTS HAVE BEEN UPDATED PRIMARILY TO ACCOUNT FOR SPATIAL COVERAGE OF SHOWERS AND THUNDERSTORMS...OVER EASTERN LARAMIE COUNTY OF WYOMING...AND OVER KIMBALL AND WESTERN CHEYENNE COUNTIES OF NEBRASKA. HAVE TOUCHED UP OTHER METEOROLOGICAL VARIABLES FOR THE REST OF THE NIGHT BASED ON TRENDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 354 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS ARE ON THE UPTICK ALONG THE INTERSTATE 80 CORRIDOR IN SOUTHEAST WY THIS AFTERNOON. AS EXPECTED...THE GREATEST COVERAGE HAS BEEN IN ALBANY IN LARAMIE COUNTIES WITH ENHANCED LOWER LEVEL CONVERGENCE ALONG THE LARAMIE RANGE. THE KCYS RADAR LOOP ALSO SHOWS NUMEROUS BOUNDARIES IN THE VICINITY OF CYS...LIKELY PLAYING A ROLE IN CONVECTIVE EVOLUTION. CLOUDS CLEARED LATE THIS AM...HELPING PUSH SFC TEMPS INTO THE 55-65 DEGREE RANGE AMID DECENT LLVL MOISTURE WITH DEWPOINTS IN THE MID 40S F. THIS BENEATH STEEP MID LEVEL LAPSE RATES ON THE ORDER OF 8-9 DEG C/KM IS CONTRIBUTING TO SBCAPES ON THE ORDER OF 1500 J/KG PER THE 21Z SPC MESOANALYSIS. GFS AND NAM BUFKIT SOUNDINGS BOTH SHOW H5 FLOW AROUND 30 KTS...WHICH COMBINED WITH GOOD VEERING IN THE SFC-500 MILLIBAR LAYER IS CONTRIBUTING TO EFFECTIVE BULK SHEAR VALUES FAVORABLE FOR ROTATING UPDRAFTS (35-45 KTS). COULD SEE A HAIL THREAT EVOLVE WITH SOME CELLS...BUT DO NOT EXPECT TO SEE MORE THAN ONE OR TWO SEVERE STORMS. OPTED TO MAINTAIN SMALL HAIL AND GUSTY WIND WORDING IN THE OFFICIAL FORECAST. LATEST HRRR HAS CHANGED VERY LITTLE FROM THIS MORNING...AND APPEARS TO BE ACCURATELY SHOWING CONVECTIVE ELEMENTS BETWEEN LARAMIE AND CHEYENNE. FOR THAT REASON... WILL MAINTAIN LIKELY POPS FOR THOSE AREAS. CONVECTIVE COVERAGE WILL DWINDLE OVERNIGHT WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. QUASI-ZONAL FLOW ALOFT PERSISTS INTO SATURDAY. A SERIES OF MID LEVEL DISTURBANCES WILL TRAVERSE THE FLOW OVER THE CENTRAL ROCKIES...ONCE AGAIN PROMOTING AFTERNOON CONVECTION CHANCES. THE DAY 2 SPC OUTLOOK HAS SHIFTED THE MARGINAL RISK EAST OF OUR CWA...WHICH MAKES SENSE AS THE LATEST IN-HOUSE WRF PLACES THE BEST INSTABILITY AXIS EAST OF AN ALLIANCE TO SIDNEY LINE BETWEEN 18-20Z SAT. POTENTIAL FOR WIDESPREAD THUNDERSTORMS WILL DEPEND ON THE TIMING OF THE DRYLINE. GFS AND NAM BOTH PUSH THIS FEATURE EAST OF THE CWA BY EARLY TO MID AFTERNOON... BUT MODELS TEND TO MIX DRYLINES A BIT QUICKLY. LATER SHIFTS MAY NEED TO ADJUST POPS ACCORDINGLY IF IT APPEARS THE LOW-LEVEL CONVERGENCE ZONE WILL HANG ANY FURTHER WEST. A MUCH WARMER DAY APPEARS TO BE ON TAP TOMORROW FOR THE PLAINS WITH WESTERLY DOWNSLOPE FLOW...AND 700 MILLIBAR TEMPS AROUND 8-10 DEG C. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 354 PM MDT FRI MAY 1 2015 THIS PERIOD WILL BE DOMINATED BY GENERALLY CONSISTENT SOUTHWEST FLOW ACROSS THE INTERMOUNTAIN WEST AS YET ANOTHER LARGE SCALE TROUGH IS CARVED INTO THE WRN CONUS. MOISTURE ADVECTION ALONG WITH DIFFICULT TO TIME SHORTWAVES EMBEDDED WITHIN THIS FLOW WILL SET THE STAGE FOR A RELATIVELY UNSETTLED PERIOD. THIS BEGINS ON SUNDAY/MONDAY AS WEAK SFC BOUNDARY SETTLES SOUTH ACROSS THE PLAINS HANGING UP AROUND THE FRONT RANGE. MEANWHILE...RELATIVELY WEAK SHORTWAVE ENERGY WILL LIFT ACROSS THIS BOUNDARY AND WHEN COMBINED WITH WEAK INSTABILITY PROGS (SBCAPE 300- 500 J/KG) WILL PRODUCE AFTERNOON/EVENING CONVECTION BOTH DAYS. A STRONGER EJECTING TROUGH WILL MOVE THROUGH THE CWFA TUE/WED. BUT WITH MORE MOISTURE AND THICKER CLOUD CANOPY...INSTABILITIES ARE PROGD TO BE LESS. SOUTHWEST FLOW PERSISTS INTO THURSDAY WITH THE NEXT TROUGH SWINGING OUT OF THE DEEPENING WEST COAST TROUGH FOR FRIDAY OR FRIDAY NIGHT...DEPENDING ON THE MEDIUM RANGE GUIDANCE OF CHOICE. ISOLATED TO SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS ARE HARD TO ARGUE WITH REALLY ANY DAY NEXT WEEK. SO HAVE KEPT PRECIP CHANCES FAIRLY BROAD BRUSH BUT NOT WIDESPREAD NEXT WEEK. SUNDAY WILL BE THE WARMEST DAY OF THE WEEK WITH HIGHS REACHING THE 60S/70S. HIGHS WILL FALL BACK INTO THE 60S GENERALLY MON-FRI. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 536 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS WILL DIE OFF ACROSS FAR SOUTHEAST WYOMING AND SOUTHERN NEBRASKA PANHANDLE OVER THE NEXT FEW HOURS. OTHER THAN LOCAL MVFR NEAR SHOWERS AND THUNDERSTORMS MAINLY LOOKING AT VFR THROUGH THE TAF PERIOD...ALTHOUGH PATCHY RADIATION FOG IS POSSIBLE LATE TONIGHT WITH LIGHT WINDS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON...SOME WITH GUSTY WINDS AND SMALL HAIL. && .FIRE WEATHER... ISSUED AT 354 PM MDT FRI MAY 1 2015 FIRE WEATHER CONCERNS WILL BE ON THE LOW SIDE WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. WHILE ANY GIVEN STORM MAY PRODUCE GUSTY AND ERRATIC WINDS...NO DRY LIGHTNING IS EXPECTED. AFTERNOON RELATIVE HUMIDITY VALUES SHOULD REMAIN ABOVE 15 PERCENT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...RUBIN SHORT TERM...CLH LONG TERM...CAH AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
549 PM MDT FRI MAY 1 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 354 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS ARE ON THE UPTICK ALONG THE INTERSTATE 80 CORRIDOR IN SOUTHEAST WY THIS AFTERNOON. AS EXPECTED...THE GREATEST COVERAGE HAS BEEN IN ALBANY IN LARAMIE COUNTIES WITH ENHANCED LOWER LEVEL CONVERGENCE ALONG THE LARAMIE RANGE. THE KCYS RADAR LOOP ALSO SHOWS NUMEROUS BOUNDARIES IN THE VICINITY OF CYS...LIKELY PLAYING A ROLE IN CONVECTIVE EVOLUTION. CLOUDS CLEARED LATE THIS AM...HELPING PUSH SFC TEMPS INTO THE 55-65 DEGREE RANGE AMID DECENT LLVL MOISTURE WITH DEWPOINTS IN THE MID 40S F. THIS BENEATH STEEP MID LEVEL LAPSE RATES ON THE ORDER OF 8-9 DEG C/KM IS CONTRIBUTING TO SBCAPES ON THE ORDER OF 1500 J/KG PER THE 21Z SPC MESOANALYSIS. GFS AND NAM BUFKIT SOUNDINGS BOTH SHOW H5 FLOW AROUND 30 KTS...WHICH COMBINED WITH GOOD VEERING IN THE SFC-500 MILLIBAR LAYER IS CONTRIBUTING TO EFFECTIVE BULK SHEAR VALUES FAVORABLE FOR ROTATING UPDRAFTS (35-45 KTS). COULD SEE A HAIL THREAT EVOLVE WITH SOME CELLS...BUT DO NOT EXPECT TO SEE MORE THAN ONE OR TWO SEVERE STORMS. OPTED TO MAINTAIN SMALL HAIL AND GUSTY WIND WORDING IN THE OFFICIAL FORECAST. LATEST HRRR HAS CHANGED VERY LITTLE FROM THIS MORNING...AND APPEARS TO BE ACCURATELY SHOWING CONVECTIVE ELEMENTS BETWEEN LARAMIE AND CHEYENNE. FOR THAT REASON... WILL MAINTAIN LIKELY POPS FOR THOSE AREAS. CONVECTIVE COVERAGE WILL DWINDLE OVERNIGHT WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. QUASI-ZONAL FLOW ALOFT PERSISTS INTO SATURDAY. A SERIES OF MID LEVEL DISTURBANCES WILL TRAVERSE THE FLOW OVER THE CENTRAL ROCKIES...ONCE AGAIN PROMOTING AFTERNOON CONVECTION CHANCES. THE DAY 2 SPC OUTLOOK HAS SHIFTED THE MARGINAL RISK EAST OF OUR CWA...WHICH MAKES SENSE AS THE LATEST IN-HOUSE WRF PLACES THE BEST INSTABILITY AXIS EAST OF AN ALLIANCE TO SIDNEY LINE BETWEEN 18-20Z SAT. POTENTIAL FOR WIDESPREAD THUNDERSTORMS WILL DEPEND ON THE TIMING OF THE DRYLINE. GFS AND NAM BOTH PUSH THIS FEATURE EAST OF THE CWA BY EARLY TO MID AFTERNOON... BUT MODELS TEND TO MIX DRYLINES A BIT QUICKLY. LATER SHIFTS MAY NEED TO ADJUST POPS ACCORDINGLY IF IT APPEARS THE LOW-LEVEL CONVERGENCE ZONE WILL HANG ANY FURTHER WEST. A MUCH WARMER DAY APPEARS TO BE ON TAP TOMORROW FOR THE PLAINS WITH WESTERLY DOWNSLOPE FLOW...AND 700 MILLIBAR TEMPS AROUND 8-10 DEG C. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 354 PM MDT FRI MAY 1 2015 THIS PERIOD WILL BE DOMINATED BY GENERALLY CONSISTENT SOUTHWEST FLOW ACROSS THE INTERMOUNTAIN WEST AS YET ANOTHER LARGE SCALE TROUGH IS CARVED INTO THE WRN CONUS. MOISTURE ADVECTION ALONG WITH DIFFICULT TO TIME SHORTWAVES EMBEDDED WITHIN THIS FLOW WILL SET THE STAGE FOR A RELATIVELY UNSETTLED PERIOD. THIS BEGINS ON SUNDAY/MONDAY AS WEAK SFC BOUNDARY SETTLES SOUTH ACROSS THE PLAINS HANGING UP AROUND THE FRONT RANGE. MEANWHILE...RELATIVELY WEAK SHORTWAVE ENERGY WILL LIFT ACROSS THIS BOUNDARY AND WHEN COMBINED WITH WEAK INSTABILITY PROGS (SBCAPE 300- 500 J/KG) WILL PRODUCE AFTERNOON/EVENING CONVECTION BOTH DAYS. A STRONGER EJECTING TROUGH WILL MOVE THROUGH THE CWFA TUE/WED. BUT WITH MORE MOISTURE AND THICKER CLOUD CANOPY...INSTABILITIES ARE PROGD TO BE LESS. SOUTHWEST FLOW PERSISTS INTO THURSDAY WITH THE NEXT TROUGH SWINGING OUT OF THE DEEPENING WEST COAST TROUGH FOR FRIDAY OR FRIDAY NIGHT...DEPENDING ON THE MEDIUM RANGE GUIDANCE OF CHOICE. ISOLATED TO SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS ARE HARD TO ARGUE WITH REALLY ANY DAY NEXT WEEK. SO HAVE KEPT PRECIP CHANCES FAIRLY BROAD BRUSH BUT NOT WIDESPREAD NEXT WEEK. SUNDAY WILL BE THE WARMEST DAY OF THE WEEK WITH HIGHS REACHING THE 60S/70S. HIGHS WILL FALL BACK INTO THE 60S GENERALLY MON-FRI. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 536 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS WILL DIE OFF ACROSS FAR SOUTHEAST WYOMING AND SOUTHERN NEBRASKA PANHANDLE OVER THE NEXT FEW HOURS. OTHER THAN LOCAL MVFR NEAR SHOWERS AND THUNDERSTORMS MAINLY LOOKING AT VFR THROUGH THE TAF PERIOD...ALTHOUGH PATCHY RADIATION FOG IS POSSIBLE LATE TONIGHT WITH LIGHT WINDS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS SATURDAY AFTERNOON...SOME WITH GUSTY WINDS AND SMALL HAIL. && .FIRE WEATHER... ISSUED AT 354 PM MDT FRI MAY 1 2015 FIRE WEATHER CONCERNS WILL BE ON THE LOW SIDE WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. WHILE ANY GIVEN STORM MAY PRODUCE GUSTY AND ERRATIC WINDS...NO DRY LIGHTNING IS EXPECTED. AFTERNOON RELATIVE HUMIDITY VALUES SHOULD REMAIN ABOVE 15 PERCENT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...CLH LONG TERM...CAH AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1211 PM MDT THU APR 30 2015 .UPDATE... ISSUED AT 955 AM MDT THU APR 30 2015 TODAYS FORECAST LOOKS TO BE RIGHT ON TRACK. SUNNY SKIES THIS MORNING WILL GIVE WAY TO SHOWERS AND ISOLATED THUNDERSTORM ACTIVITY THIS AFTERNOON AND EVENING...PARTICULARLY INTO SOUTHERN PORTIONS OF THE FORECAST AREA. THE MAIN FOCUS FOR SHOWERS AND THUNDERSTORMS WILL BE NEAR A MIDLEVEL FRONTAL BOUNDARY WHICH WILL HANG UP NEAR THE INTERSTATE 80 CORRIDOR THIS AFTERNOON AND EVENING. RELATIVELY COOL AND STABLE AIR WILL BE FOUND FARTHER NORTH...MAKING CONVECTION LESS OF A CONCERN. WILL KEEP AN EYE ON CAPE VALUES THIS AFTERNOON...BUT THERE ARE BIG DIFFERENCES AMONGST MODELS WITH THE NAM SHOWING 1000-1500 J/KG CAPE. THIS APPEARS TO BE A BIT TOO HIGH WHICH SEEMS TO BE COMMON IN THE NAM OUTPUT. THE GFS AND RUC SEEM MORE REASONABLE AROUND 500 J/KG OR LESS THIS AFTERNOON. REGARDLESS...NOT EXPECTING SEVERE THUNDERSTORMS WITH ANY CHANCE FOR SEVERE THUNDERSTORMS VERY LOW. GENERALLY LOOKING FOR GARDEN VARIETY THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS POSSIBLE WITH A FEW STRONGER THUNDERSTORMS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 230 AM MDT THU APR 30 2015 UPPER RIDGE AXIS SHIFTING EAST OF THE CWA THIS MORNING WITH AN UPPER SHORTWAVE MOVING EAST OVER THE NW PART OF THE COUNTRY. THIS SYSTEM WILL PROGRESS RATHER QUICKLY EAST THROUGH THIS EVENING AND PUSH A COLD FRONT ACROSS THE CWA BY LATE THIS AFTERNOON. UPSLOPE FLOW AND SOME INSTABILITY WILL ALLOW FOR SCTD SHOWERS AND A FEW TSTRMS TO DEVELOP OVER SE WY THIS AFTERNOON WITH ACTIVITY PROGRESSING EAST ACROSS THE PANHANDLE THIS EVENING. A NARROW BAND OF DECENT CAPE PROGGED THIS AFTERNOON OVER THE SRN PANHANDLE AND FAR SE WY WITH VALUES FROM ABOUT 500-1000J/KG SO A STRONGER STORM OR TWO NOT OUT OF THE QUESTION. ACTIVITY SHOULD END LATER THIS EVENING AS A SFC HIGH SETTLES DOWN THE HIGH PLAINS AND INSTABILITY FALLS OFF. ZONAL UPPER FLOW THEN SETS UP OVER THE CWA FRIDAY THROUGH SATURDAY WITH SEVERAL RIPPLES IN THIS FLOW. SHOULD SEE SOME CONVECTION FIRE MAINLY OVER THE SRN MTNS FRIDAY AFTERNOON THEN GREATER COVERAGE OF ACTIVITY SATURDAY AFTERNOON. TEMPS MILD THROUGH THE PERIOD. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 230 AM MDT THU APR 30 2015 UNSETTLED WEATHER LOOKS LIKELY IN THE LONG TERM AS A VERY SLOW MOVING UPPER LOW MOVES THROUGH THE AREA. AFTERNOON CONVECTION COULD STILL BE ONGOING SATURDAY EVENING ALONG THE I-80 CORRIDOR FROM CHEYENNE TO RAWLINS. CONVECTION FORECAST TO COME TO AN END THOUGH TOWARDS MIDNIGHT. GUIDANCE STILL SHOWS A BOUNDARY LAYING ALONG THE LARAMIE RANGE SUNDAY AND THIS WILL BE THE FOCUSING MECHANISM FOR MORE WIDESPREAD SHOWERS AND THUNDERSTORMS SUNDAY AFTERNOON. SOME DIFFERENCES BETWEEN THE GFS AND ECMWF ON LOCATION OF THE CONVECTION. GFS FOCUSING ON AREAS EAST OF THE LARAMIE RANGE WHILE ECMWF CONCENTRATING ON AREAS WEST. TENDING TOWARDS THE ECMWF SOLUTION AND CONCENTRATED HIGHER POPS WEST. WEAK UPPER TROUGH MOVES THROUGH SUNDAY NIGHT INTO MONDAY MORNING SHOULD MOVE CONVECTION EAST INTO THE PANHANDLE OVERNIGHT. BUT CONVECTION BLOSSOMS AGAIN OVER SOUTHEAST WYOMING MONDAY AFTERNOON AS ANOTHER PIECE OF ENERGY SPINS OFF A LOW OVER THE DESERT SOUTHWEST. SURFACE HIGH PRESSURE OVER THE DAKOTAS WILL GIVE US A FAVORABLE SOUTHEAST UPSLOPE FLOW THAT WILL ENHANCE SHOWERS EAST OF THE LARAMIE RANGE. BOTH THE GFS AND ECMWF SHOW POSSIBILITY OF HEAVY RAIN OVER THE SOUTHERN PANHANDLE INTO THE CHEYENNE AREA MONDAY EVENING. BY TUESDAY...UPPER LOW FORECAST TO BE MOVING INTO SOUTHWESTERN COLORADO. A 60KT JET FINGER IN A FAVORABLE LOCATION FOR SOUTHEAST WYOMING AND NEBRASKA PANHANDLE TO SEE THE POSSIBILITY OF SOME SEVER THUNDERSTORMS TUESDAY. SOMETHING THAT WILL BECOME CLEARER AS WE CLOSER TO THE EVENT. LOW FORECAST TO MOVE INTO EASTERN COLORADO WEDNESDAY. SHOULD SEE WIDESPREAD SHOWERS/THUNDERSTORMS DURING THE DAY WEDNESDAY. GOOD NEWS IS THAT BOTH GFS AND ECMWF ARE KEEPING WARM TEMPERATURES AT 700MBS...AROUND +6C...SO PRECIP WILL FALL AS LIQUID AND NOT AS SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1208 PM MDT THU APR 30 2015 VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS. ISOLATED TO WIDELY SCATTERED SHOWERS AND STORMS WILL DEVELOP ACROSS MUCH OF THE AREA THIS AFTERNOON...WITH SHOWERS BECOMING MORE WIDESPREAD OVER THE WESTERN PANHANDLE DURING THE EVENING AND OVERNIGHT. ANY SHOWERS AND THUNDERSTORMS COULD BE ACCOMPANIED BY GUSTY/ERRATIC WINDS AND BRIEF MVFR VSBYS. && .FIRE WEATHER... ISSUED AT 230 AM MDT THU APR 30 2015 A COOL FRONT WILL PASS ACROSS THE DISTRICTS TODAY BRINGING A NORTHERLY WIND SWITCH AND SCATTERED SHOWERS AND A FEW TSTRMS THIS AFTERNOON INTO THIS EVENING. CONCERNS LOW OVERALL THROUGH THE UPCOMING WEEKEND WITH NON-CRITICAL WEATHER CONDITIONS AND GREENING FUELS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...SML SHORT TERM...RE LONG TERM...GCC AVIATION...CLH FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
956 AM MDT THU APR 30 2015 .UPDATE... ISSUED AT 955 AM MDT THU APR 30 2015 TODAYS FORECAST LOOKS TO BE RIGHT ON TRACK. SUNNY SKIES THIS MORNING WILL GIVE WAY TO SHOWERS AND ISOLATED THUNDERSTORM ACTIVITY THIS AFTERNOON AND EVENING...PARTICULARLY INTO SOUTHERN PORTIONS OF THE FORECAST AREA. THE MAIN FOCUS FOR SHOWERS AND THUNDERSTORMS WILL BE NEAR A MIDLEVEL FRONTAL BOUNDARY WHICH WILL HANG UP NEAR THE INTERSTATE 80 CORRIDOR THIS AFTERNOON AND EVENING. RELATIVELY COOL AND STABLE AIR WILL BE FOUND FARTHER NORTH...MAKING CONVECTION LESS OF A CONCERN. WILL KEEP AN EYE ON CAPE VALUES THIS AFTERNOON...BUT THERE ARE BIG DIFFERENCES AMONGST MODELS WITH THE NAM SHOWING 1000-1500 J/KG CAPE. THIS APPEARS TO BE A BIT TOO HIGH WHICH SEEMS TO BE COMMON IN THE NAM OUTPUT. THE GFS AND RUC SEEM MORE REASONABLE AROUND 500 J/KG OR LESS THIS AFTERNOON. REGARDLESS...NOT EXPECTING SEVERE THUNDERSTORMS WITH ANY CHANCE FOR SEVERE THUNDERSTORMS VERY LOW. GENERALLY LOOKING FOR GARDEN VARIETY THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS POSSIBLE WITH A FEW STRONGER THUNDERSTORMS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 230 AM MDT THU APR 30 2015 UPPER RIDGE AXIS SHIFTING EAST OF THE CWA THIS MORNING WITH AN UPPER SHORTWAVE MOVING EAST OVER THE NW PART OF THE COUNTRY. THIS SYSTEM WILL PROGRESS RATHER QUICKLY EAST THROUGH THIS EVENING AND PUSH A COLD FRONT ACROSS THE CWA BY LATE THIS AFTERNOON. UPSLOPE FLOW AND SOME INSTABILITY WILL ALLOW FOR SCTD SHOWERS AND A FEW TSTRMS TO DEVELOP OVER SE WY THIS AFTERNOON WITH ACTIVITY PROGRESSING EAST ACROSS THE PANHANDLE THIS EVENING. A NARROW BAND OF DECENT CAPE PROGGED THIS AFTERNOON OVER THE SRN PANHANDLE AND FAR SE WY WITH VALUES FROM ABOUT 500-1000J/KG SO A STRONGER STORM OR TWO NOT OUT OF THE QUESTION. ACTIVITY SHOULD END LATER THIS EVENING AS A SFC HIGH SETTLES DOWN THE HIGH PLAINS AND INSTABILITY FALLS OFF. ZONAL UPPER FLOW THEN SETS UP OVER THE CWA FRIDAY THROUGH SATURDAY WITH SEVERAL RIPPLES IN THIS FLOW. SHOULD SEE SOME CONVECTION FIRE MAINLY OVER THE SRN MTNS FRIDAY AFTERNOON THEN GREATER COVERAGE OF ACTIVITY SATURDAY AFTERNOON. TEMPS MILD THROUGH THE PERIOD. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 230 AM MDT THU APR 30 2015 UNSETTLED WEATHER LOOKS LIKELY IN THE LONG TERM AS A VERY SLOW MOVING UPPER LOW MOVES THROUGH THE AREA. AFTERNOON CONVECTION COULD STILL BE ONGOING SATURDAY EVENING ALONG THE I-80 CORRIDOR FROM CHEYENNE TO RAWLINS. CONVECTION FORECAST TO COME TO AN END THOUGH TOWARDS MIDNIGHT. GUIDANCE STILL SHOWS A BOUNDARY LAYING ALONG THE LARAMIE RANGE SUNDAY AND THIS WILL BE THE FOCUSING MECHANISM FOR MORE WIDESPREAD SHOWERS AND THUNDERSTORMS SUNDAY AFTERNOON. SOME DIFFERENCES BETWEEN THE GFS AND ECMWF ON LOCATION OF THE CONVECTION. GFS FOCUSING ON AREAS EAST OF THE LARAMIE RANGE WHILE ECMWF CONCENTRATING ON AREAS WEST. TENDING TOWARDS THE ECMWF SOLUTION AND CONCENTRATED HIGHER POPS WEST. WEAK UPPER TROUGH MOVES THROUGH SUNDAY NIGHT INTO MONDAY MORNING SHOULD MOVE CONVECTION EAST INTO THE PANHANDLE OVERNIGHT. BUT CONVECTION BLOSSOMS AGAIN OVER SOUTHEAST WYOMING MONDAY AFTERNOON AS ANOTHER PIECE OF ENERGY SPINS OFF A LOW OVER THE DESERT SOUTHWEST. SURFACE HIGH PRESSURE OVER THE DAKOTAS WILL GIVE US A FAVORABLE SOUTHEAST UPSLOPE FLOW THAT WILL ENHANCE SHOWERS EAST OF THE LARAMIE RANGE. BOTH THE GFS AND ECMWF SHOW POSSIBILITY OF HEAVY RAIN OVER THE SOUTHERN PANHANDLE INTO THE CHEYENNE AREA MONDAY EVENING. BY TUESDAY...UPPER LOW FORECAST TO BE MOVING INTO SOUTHWESTERN COLORADO. A 60KT JET FINGER IN A FAVORABLE LOCATION FOR SOUTHEAST WYOMING AND NEBRASKA PANHANDLE TO SEE THE POSSIBILITY OF SOME SEVER THUNDERSTORMS TUESDAY. SOMETHING THAT WILL BECOME CLEARER AS WE CLOSER TO THE EVENT. LOW FORECAST TO MOVE INTO EASTERN COLORADO WEDNESDAY. SHOULD SEE WIDESPREAD SHOWERS/THUNDERSTORMS DURING THE DAY WEDNESDAY. GOOD NEWS IS THAT BOTH GFS AND ECMWF ARE KEEPING WARM TEMPERATURES AT 700MBS...AROUND +6C...SO PRECIP WILL FALL AS LIQUID AND NOT AS SNOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 528 AM MDT THU APR 30 2015 FIRST OFF...DO BELIEVE WE ARE HAVING ISSUES WITH THE KCYS VISIBILITY SENSOR THIS MORNING. WILL HAVE TECHNICIANS CHECK IT OUT WHEN THEY COME IN. VISIBILITY HERE AT KCYS IS IN GOOD SHAPE. VFR CONDITIONS MOST OF THE DAY TODAY FOR ALL SOUTHEAST WYOMING AND NEBRASKA PANHANDLE AIRPORTS. COLD FRONT STILL ON TRACK TO MOVE INTO THE AREA FROM WEST TO EAST THIS AFTERNOON...SO COULD BE LOOKING AT SHOWERS AND THUNDERSTORMS BEGINNING AT KRWL SHORTLY AFTER 19Z. SREF GUIDANCE SHOWING LOWERING CONDITIONS HERE AT KCYS AFTER 06Z WITH NORTHEAST UPSLOPE WINDS BEHIND THE FRONT. STARTED TRENDING KCYS DOWN TO ACCOUNT FOR THIS. && .FIRE WEATHER... ISSUED AT 230 AM MDT THU APR 30 2015 A COOL FRONT WILL PASS ACROSS THE DISTRICTS TODAY BRINGING A NORTHERLY WIND SWITCH AND SCATTERED SHOWERS AND A FEW TSTRMS THIS AFTERNOON INTO THIS EVENING. CONCERNS LOW OVERALL THROUGH THE UPCOMING WEEKEND WITH NON-CRITICAL WEATHER CONDITIONS AND GREENING FUELS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...SML SHORT TERM...RE LONG TERM...GCC AVIATION...GCC FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1242 AM MDT SAT MAY 2 2015 .UPDATE... ISSUED AT 1242 AM MDT SAT MAY 2 2015 WITH CLEARING SKIES AND DECREASING DEWPOINT DEPRESSIONS OVER WELD COUNTY...AS WELL AS THE HRRR AND RAP HI RES MODELS SHOWING SOME VISIBILITY REDUCTIONS IN A FEW HOURS....HAVE ADDED SOME PATCHY FOG ALONG THE SOUTH PLATTE RIVER VALLEY IN WELD...MORGAN AND LOGAN COUNTIES THROUGH MID MORNING HOURS. UPDATE ISSUED AT 945 PM MDT FRI MAY 1 2015 MINOR UPDATES PLANNED AT THIS TIME. MAINLY SOME LINGERING SHOWERS THIS EVENING. WL GO WITH SHOWERS VS TSTMS IN THE GRIDS FOR THE REST OF THIS EVENING. UPDATE ISSUED AT 641 PM MDT FRI MAY 1 2015 THE FOCUS FOR THUNDERSTORMS HAS SHIFTED TO THE NORTH AND EAST OF DENVER FOR THE MOST PART SO HAVE STARTED TO BACK OFF THE POPS ESPECIALLY OVER THE WESTERN PART OF THE CWA. THE POPS MAY STILL BE A BIT OVERDONE SINCE THE HRRR HINTS AT SOME ADDITIONAL ACTIVITY OVER THE NEXT COUPLE OF HOURS...MAINLY TO THE NORTH NEAR FORT COLLINS AND GREELEY. NOT CONVINCED THIS WILL HAPPEN BUT DO NOT WANT TO LESSEN THE POPS ANY FURTHER TIL I KNOW FOR SURE. IF A STRONG ENOUGH OUTFLOW COULD SLIPS INTO DENVER FROM THE NORTH...IT COULD STILL TRIGGER SOME ADDITIONAL DEVELOPMENT. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 THUNDERSTORMS ARE PRESENTLY MOVING OVER THE PALMER DIVIDE AND OFF THE FOOTHILLS OF BOULDER AND JEFFERSON COUNTY. SOUTHEASTERLY LOW LEVEL WINDS AND SURFACE DEW POINTS IN THE MID AND UPPER 40S SHOULD BE SUFFICIENT TO KEEP THUNDERSTORMS DEVELOPING ACROSS THE PLAINS EARLY THIS EVENING. HAIL UP TO THREE-QUARTERS OF AN INCH WILL BE THE MOST COMMON THREAT FROM THE PULSE-TYPE CONVECTION. WIND SHEAR ALOFT DOES NOT SEEM TO BE STRONG ENOUGH FOR ORGANIZED SUPERCELLS TO DEVELOP. RAINFALL AMOUNTS FROM ALERT GAGES HAVE SHOWN RAINFALL AMOUNTS STAYING LESS THAN A HALF INCH. SOME AREAS MAY RECEIVE SOME STANDING WATER IMMEDIATELY AFTER STORM PASSAGE...BUT NO OTHER PROBLEMS ARE EXPECTED. SKIES SHOULD BECOME PARTLY CLOUDY TO MOSTLY CLEAR LATER TONIGHT AFTER THE EVENING CONVECTION DIES DOWN. SOUTHERLY WINDS ARE EXPECTED TO PREVAIL AS HIGH PRESSURE BUILDS OVER THE CENTRAL PLAINS. TOMORROW SHOULD BE A REPEAT OF TODAY AS THE FLAT UPPER RIDGE REMAINS OVER COLORADO AND MOISTURE REMAINS OVER THE STATE. DAYTIME HEATING WILL AGAIN BE SUFFICIENT TO DE-STABILIZE THE AIRMASS. ONCE AGAIN THE WIND STRUCTURE WILL BE WEAK...SO ONLY SCATTERED NON-SEVERE THUNDERSTORMS ARE EXPECTED. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 341 PM MDT FRI MAY 1 2015 MODELS HAVE WEAK SOUTHWESTERLY FLOW ALOFT FOR THE CWA SATURDAY NIGHT THROUGH MONDAY WITH A WEAK UPPER CLOSED LOW TO MOVE INTO THE FOUR CORNERS BY 12Z TUESDAY MORNING. THE QG FIELDS HAVE WEAK UPWARD VERTICAL VELOCITY PROGGED FOR ALL THE CWA SATURDAY NIGHT THROUGH MONDAY NIGHT. THE BOUNDARY LAYER WINDS WILL BE PRETTY WEAK WITH NORMAL DIURNAL PATTERNS SATURDAY NIGHT. THEN A WEAK COLD FRONT WITH UPSLOPE NORTHEASTERLIES ARE PROGGED SUNDAY...WITH EAST-SOUTHEASTERLIES SUNDAY NIGHT THROUGH MONDAY NIGHT. MOISTURE- WISE...SATURDAY EVENING IS FAIRLY DRY. THIS CARRIES INTO SUNDAY MORNING...WITH A SIGNIFICANT INCREASE IN MOISTURE SUNDAY AFTERNOON. BY SUNDAY NIGHT...THE NAM AND ECMWF FURTHER INCREASE MOISTURE...CONTINUING INTO MONDAY. THE GFS DOES NOT DO THIS UNTIL MONDAY AFTERNOON. BOTH THE GFS AND ECMWF SHOW A VERY MOIST MONDAY NIGHT. THE QPF FIELDS HAVE A TAD OF MEASURABLE PRECIPITATION PROGGED SATURDAY EVENING. BY SUNDAY AFTERNOON...THERE IS MUCH MORE PROGGED. THERE IS QPF NOTED ALL SUNDAY NIGHT...MONDAY MORNING... THROUGH MONDAY EVENING...THEN LESS MONDAY OVERNIGHT. THE DEW POINTS ARE IN THE 30S AND LOWER 40S F SATURDAY NIGHT INTO SUNDAY...THEN THEY INCREASE INTO THE 40S TO LOWER 50S FROM LATER SUNDAY THROUGH MONDAY NIGHT. THERE IS SOME CAPE BOTH SATURDAY EVENING...THEN LATE DAY SUNDAY AS WELL...BUT VALUES ARE NOT ABOVE 1000 J/KG EITHER DAY. THERE IS LESS CAPE AROUND FOR LATE DAY MONDAY WITH NONE OVER THE EASTERN HALF OF THE PLAINS. FOR POPS...MINOR ONES SATURDAY EVENING...NOTHING OVERNIGHT...THEN MINOR AGAIN IN THE MOUNTAINS SUNDAY MORNING. BY SUNDAY AFTERNOON THROUGH MONDAY NIGHT WILL GO WITH 30-50%S. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 3-5 C COOLER THAN SATURDAY`S. MONDAY`S HIGHS ARE 1-5 C COOLER AGAIN FROM SUNDAY`S. FOR THE LATER DAYS...TUESDAY THROUGH FRIDAY...MODELS CONTINUE TO SHOW UPPER TROUGHINESS FOR THE CWA ALL FOUR DAYS. THERE IS GOOD MOISTURE MUCH OF THE TIME WITH THE EXCEPTION OF FRIDAY. IT WILL BE A WET...UNSETTLED PERIOD WITH TEMPERATURES A BIT BELOW NORMALS. && .AVIATION...(FOR THE TAFS THROUGH 06Z SATURDAY EVENING) ISSUED AT 945 PM MDT FRI MAY 1 2015 VFR CONDITIONS THROUGH MID AFTERNOON SATURDAY WITH DRAINAGE WINDS OVERNIGHT. COULD SEE ILS CIGS DEVELOPS WITH ANY DEVELOPING TSTMS AFTER 21Z SATURDAY. COVERAGE APPEARS ISOLATED WITH BETTER COVERAGE NORTH OF DENVER IF A WEAK DISTURBANCE MAKES ITS WAY ALONG THE NORTHERN BORDER IN THE AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KRIEDERMAN SHORT TERM...DANKERS LONG TERM...RJK AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1130 PM MDT FRI MAY 1 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 257 PM MDT FRI MAY 1 2015 ...STORMS MOVING INTO EASTERN COLORADO THIS EVENING... ...WARM WEEKEND ON THE WAY... LATEST HRRR HAS A DECENT HANDLE ON THE CONVECTION...AND ALONG WITH OTHER HI-RES GUIDANCE SHOWS A WAVE OF CONVECTION INCREASING IN COVERAGE OVER THE I-25 CORRIDOR THIS AFTERNOON...THEN CLEARING I-25 BY 00-01Z THIS EVENING. STORMS WILL THEN CONSOLIDATE INTO AN MCS OVER THE ERN PLAINS THIS EVENING. THEN...SHOULD SEE SHOWERS AND STORMS MOVING INTO WRN KS BY 03Z OR SO THIS EVE. AFTER 06Z...PRECIP SHOULD BE OVER FOR MOST OF THE AREA...WITH JUST SOME LINGERING SHOWERS POSSIBLE OVER THE FAR ERN PLAINS AND HYR TRRN. UPPER RIDGE AND ASSOCIATED AVA SHOULD HELP SUPPRESS THINGS THROUGH SAT MORNING. TOMORROW...A WARMER DAY IS IN STORE...AS FLOW BECOMES A BIT MORE ZONAL AND H7 TEMPS RISE TO AROUND 10 DEG C. EXPECT 80 PLUS DEG TEMPS OVER MUCH OF THE PLAINS BY AFTERNOON...WITH 60S AND 70S FOR THE HIGHER ELEVATIONS. ANOTHER WEAK DISTURBANCE WILL SPARK SOME AFTERNOON STORMS MOVING OFF THE MTS SAT AFTERNOON...BUT WITH DEW POINTS IN THE 30S CONVECTION WILL NOT BE AS STRONG AS IT IS/WILL BE TODAY...AND COVERAGE A BIT LESS AS WELL. ROSE .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 257 PM MDT FRI MAY 1 2015 A RATHER WET PERIOD IS EXPECTED THE FIRST PART HALF OF NEXT WEEK. ON SUN AN UPR TROF WL MOVE TO ALONG THE CA COAST...WITH MSTR AHEAD OF THIS SYSTEM MOVING INTO THE FORECAST AREA...ALONG WITH A SHORTWAVE TROF IN THE AFTERNOON AND EVENING HOURS. IT STILL LOOKS LIKE A FRONT WL HANG UP ALONG THE PALMER DVD SUN AFTERNOON AND THEN WORK ITS WAY SOUTH IN THE EVENING HOURS. MUCH OF THE AREA WL SEE AT LEAST ISOLD TO SCT SHOWERS AND TSTMS SUN AND SUN EVENING. HIGH TEMPS ON SUN SHOULD STILL BE ABOVE AVERAGE BY ABOUT 5-10 DEG. ON MON THE UPR TROF MOVES INTO THE WRN STATES...WITH AN UPR LOW CENTER EXPECTED TO BE OVR SWRN AZ BY 00Z TUE. MSTR WL CONTINUE STREAMING INTO THE FORECAST AREA AHEAD OF THIS SYSTEM. OVR ERN PORTIONS OF THE FORECAST AREA...LOW TO MID LEVEL SERLY WINDS SHOULD HELP ENHANCE PCPN CHANCE ALONG AND ADJACENT TO THE ERN MTNS. WIDESPREAD PCPN IS EXPECTED ON MON ALONG WITH COOLER TEMPS. THE ECMWF AND GFS LIFT THE UPR LOW NORTHEASTWARD ON TUE. THE GFS IS A LITTLE FARTHER NORTH THAN THE GFS WITH THE LOW CENTER. THE GFS HAS IT IN NERN CO BY 00Z WED WITH THE ECMWF SHOWING IT OVR SERN CO. EITHER WAY...WIDESPREAD PCPN SHOULD CONTINUE THRU TUE. THIS SYSTEM WEAKENS AS IT MOVES NORTH-NORTHEASTWARD TUE NIGHT THROUGH WED...MOVING INTO THE WRN DAKOTAS BY 00Z THU. ALTHOUGH PCPN CHANCES ARE EXPECTED TO DECREASE SOME TUE NIGHT...THERE SHOULD STILL BE PLENTY OF MSTR AROUND FOR AN INCREASE IN ACTIVITY IN THE AFTERNOON AND EVENING HOURS ON WED AS THINGS REMAIN UNSETTLED. TEMPS REMAIN QUITE WARM AS THIS SYSTEM AFFECTS THE AREA AND SNOW ACCUMULATIONS ARE GENERALLY EXPECTED TO REMAIN OVR THE HYR MTN AREAS. SOME AREAS...ESPECIALLY NR THE ERN MTN...COULD SEE PERIODS OF HEAVY RAIN. ANOTHER UPR LOW IS THEN FORECAST TO MOVE INTO THE GREAT BASIN FOR LATE THU AND FRI. THIS WL KEEP THE WX UNSETTLED WITH PROBABLY FAIRLY WIDESPREAD PCPN CHANCES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1130 PM MDT FRI MAY 1 2015 OUTSIDE OF ISOLATED PRIMARILY AFTERNOON SHOWERS AND THUNDERSTORMS...TAF SITES KALS...KCOS AND KPUB SHOULD EXPERIENCE VFR CONDITIONS INTO FRIDAY EVENING. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1148 PM CDT FRI MAY 1 2015 .SYNOPSIS... ISSUED AT 321 PM CDT FRI MAY 1 2015 WEAK FRONTAL BOUNDARY WILL DISSIPATE OVER IOWA TONIGHT AS A FRONTAL BOUNDARY DEVELOPS TO THE NORTHWEST ON SATURDAY. THIS FRONT WILL MOVE SOUTHEAST THROUGH THE AREA SUNDAY AFTERNOON AND NIGHT BEFORE STALLING. THE OVERALL WEATHER PATTERN WILL BE ACTIVE WITH THE FRONT IN THE VICINITY THROUGH THE NEXT WEEK. && .SHORT TERM /TONIGHT/... ISSUED AT 321 PM CDT FRI MAY 1 2015 MAIN FORECAST CONCERN WILL BE PRECIPITATION CHANCES THIS EVENING AND AGAIN VERY LATE IN THE PERIOD. ONGOING PRECIPITATION ACROSS CENTRAL PORTION OF THE CWA WILL PERSIST THROUGH THE EVENING...CONTINUING TO PUSH SLOWLY SOUTHEAST. WEAK BOUNDARY AND FORCING WITH PRECIPITATION WILL CONTINUE TO WEAKEN AND WILL SEE PRECIPITATION CONTINUE TO BECOME MORE SCATTERED THROUGH THE LATE EVENING. HRRR MODEL HAS A GOOD HANDLE ON PRECIPITATION TRENDS...AND HAVE TRENDED THIS WAY FOR POPS. GIVEN CURRENT LACK OF INSTABILITY HAVE LEFT THUNDER MENTION OUT...THOUGH COULD SEE SOME ISOLATED THUNDER IN THE LATE AFTERNOON OR EARLY EVENING WITH INCREASING INSTABILITY IN THE FAR WEST. SHORTWAVE LIFTING NORTH FROM KS/NE WILL BEGIN TO PUSH INTO SOUTHWEST NEAR 12Z. HAVE CUT BACK ON POPS WITH SLIGHTLY SLOWER PROGRESSION OF WAVE AND MOISTURE NOTED...NOT PUSHING INTO CWA UNTIL AFTER 12Z. HOWEVER...PLACEMENT MAY BE TOO FAR SOUTH ACROSS THE WEST. HAVE KEPT OVERNIGHT LOW TEMPERATURES DOWN A DEGREE OR TWO GIVEN HOW PRECIPITATION LIMITED DAYTIME HIGHS...AND EXPECT CLEARING SKIES ACROSS THE NORTH TONIGHT. .LONG TERM /SATURDAY THROUGH FRIDAY/... ISSUED AT 321 PM CDT FRI MAY 1 2015 CONTINUED WAA AND POCKETS OF STRONGER THETA-E WILL DOMINATE THROUGH THE NEXT WEEK. A WEAK FEATURE WILL MOVE THROUGH THE AREA ON SATURDAY BRINGING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS...BUT NOTHING TO REALLY FOCUS ON WITH THIS. SUNDAY LOOKS TO BE MORE ACTIVE AS DEW POINTS COME UP AND A STRONGER FRONT MOVES IN. CAPE RISES TO AROUND 2000 J/KG OR SO BY MID DAY SUNDAY WITH LITTLE RESIDUAL CAP. OTHER PARAMETERS ARE NOT AS FAVORABLE WITH INFLOW RELATIVELY WEAK AND OVERALL CONVERGENCE ALONG THE FRONT NOT OPTIMAL. STILL, THUNDER CHANCES ARE DECENT AND IT APPEARS THAT MARGINAL TO SLIGHT THREAD FOR SEVERE LOOKS REASONABLE. THE REST OF THE WEEK WILL BE WARMER THAN NORMAL AND WET. TROUGH IN THE WEST WILL SEND OUT PERIODIC PIECES WITH THE NEXT STRONGER PIECE ARRIVING ABOUT THURSDAY...THE NEXT BEYOND THE FORECAST PERIOD. THOUGH THE SEVERE THREAT LOOKS RELATIVELY LOW...THE CHANCES FOR WIDESPREAD RAINFALL IN EXCESS OF 2 INCHES IN A WEEK IS PRETTY GOOD. DO NOT EXPECT THE RAINFALL TO BE A PROBLEM...BUT IT WILL PUT A CRIMP IN PLANTING PROGRESS. && .AVIATION...02/06Z ISSUED AT 1148 PM CDT FRI MAY 1 2015 VERY LIGHT SHOWERS TIED TO A WEAK DISTURBANCE AND SOME WEAK FORCING ACROSS THE AREA WILL CONTINUE TO WANE OVER THE NEXT COUPLE OF HOURS. BETWEEN 12Z AND 15Z ANOTHER UPPER LEVEL DISTURBANCE AND SOME FORCING TIED TO IT WILL SHIFT ACROSS CENTRAL/SOUTHERN IOWA. THERE SHOULD BE SOME SHOWERS ASSOCIATED WITH THIS FEATURE AS WELL. WE WILL BE A BIT MORE UNSTABLE TOMORROW SO THUNDERSTORMS WILL DEVELOP AS WELL BUT LOW LEVEL MOISTURE WILL BE LACKING SO WE ARE NOT LOOKING FOR MUCH IN THE WAY OF PRECIP OR LOW CIGS DURING THE FORECAST PERIOD. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MS MAY 15 SHORT TERM...AWB LONG TERM...MS MAY 15 AVIATION...FAB
AREA FORECAST DISCUSSION
NWS TOPEKA KS
353 AM CDT Sat May 2 2015 .SHORT TERM...(Today and Tonight) Issued at 351 AM CDT SAT MAY 2 2015 Showers/isolated thunderstorms across southeast Nebraska and far northeast KS are occurring in elevated warm advection zone near convergence at nose of low-level jet. This activity has been confined to far northeastern part of forecast area and should remain there this morning. Bigger question what else gets going in central/north central KS in the next few hours and that could move across a far greater portion of northeast KS this morning. Poorly defined shortwave trough seen best in RAP analysis and also somewhat apparent in water vapor loop moving toward north central KS at the current time. HRRR, RAP and 06Z NAM all have a larger area of precip developing in the next few hours apparently associated with this feature. If it develops as forecast, it will affect a wider part of northeast KS this morning than previously thought. Have expanded area of 20-30 percent POPs this morning due to trends in short range models, but difficult to go too high with virtually nothing showing up on radar over central KS at this time. Whatever precip develops should be moving out of far northeast KS early this afternoon and expect dry conditions for the rest of this afternoon through tonight as weak ridging aloft is over the area. Temps today will depend on cloud cover with far eastern KS most likely to see the most persistent clouds and temps only in the upper 70s while some clearing this afternoon in central KS should lead to lower 80s. .LONG TERM...(Sunday through Friday) Issued at 351 AM CDT SAT MAY 2 2015 By Sunday, models show a broad mid-level ridge stretched across the southern conus with surface low pressure extending from the High Plains into the Northern Plains. With this low pressure just west of the forecast area, a decent pressure gradient is expected to set up over the area, resulting in breezy southerly winds supporting good warm-air advection across the entire forecast area. With these conditions in place, have continued to trend on the warmer side of model guidance with highs in the low/mid 80s. Models continue to hold off on the front moving into north central Kansas until Sunday evening, so have a dry forecast for the daytime hours with chance to likely PoPs Sunday night through Monday as the cold front advances into the CWA and then stalls out over the area. By Monday the mid-level ridge will be focused across the southeastern U.S. and should start building northward Monday night into Tuesday, causing the stalled cold front to lift northward as a warm front. There are still some model discrepancies with how far north the warm front will lift (near the KS/NE border or into southern NE), but have lowered or even removed PoPs from far east central Kansas Monday night with likely PoPs still near the KS/NE border. The best chance for dry conditions looks to be on Tuesday with the front likely to the north, so have continued to drop PoPs to only slight chances or even dry for some locations. However, shower and thunderstorm chances return Tuesday night as a mid-level trough over the southwestern U.S. lifts northeastward toward the area, strengthening the surface low pressure system and pushing it into the High Plains. Models seem to be coming into slightly better agreement with the tracking of the mid-level trough and surface low, with the trough lifting into the Central Plains Wed/Wed night and into the Northern Plains by Thursday. At the surface, the surface low and associated cold front look to be stalled out along the High Plains Tuesday night through Wednesday before shifting a bit further east. With this steady southerly flow into the region, should see some modest moisture advection into the area by mid- week as we should be able to tap into moisture from the Gulf of Mexico. This moisture advection along with some mid-level forcing will bring increasing chances for scattered showers and thunderstorms Tuesday night through Wednesday night with diminishing chances for the remainder of the week as we lose the mid-level forcing. With low confidence in whether or not scattered precipitation will be lingering by the end of the week, have dropped PoPs to low-end chances for Thursday night and Friday. The persistent southerly flow and moisture advection also will lead to mild conditions with highs in the 70s and lows in the 50s/60s as well as humid conditions with dewpoints steadily in the 50s/60s. && .AVIATION...(For the 06Z TAFs through 06Z Saturday Night) Issued at 1128 PM CDT FRI MAY 1 2015 VFR conditions expected through most of the taf period. Low level wind shear was not well forecasted by the models therefore have added a group based on current observations. The models are also hinting at a shortwave tracking across the area during mid day. An isolated shower or storm could be possible with this feature although confidence was too low at this point to mention. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GDP LONG TERM...Hennecke AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS GOODLAND KS
228 AM MDT SAT MAY 2 2015 .UPDATE... ISSUED AT 540 PM MDT FRI MAY 1 2015 UPDATE TO GOING FORECAST TO ACCOUNT FOR VEIL OF MID/HIGH CLOUDS CURRENTLY OVER THE AREA. ALL ACTIVITY EMANATING FROM CONVECTION OFF OVER CENTRAL COLORADO. TREND IS TO CONTINUE EASTWARD THRU THE EVENING HOURS BEFORE DECREASING AFTER MIDNIGHT. HAVE GONE WITH CLOUDY BECOMING PARTLY CLOUDY LATE FOR THE CWA. REST OF FORECAST IS ON TRACK AT THIS TIME. CONVECTION OVER CENTRAL COLORADO IS FINALLY EDGING INTO PORTIONS OF EASTERN COLORADO...SO WILL LEAVE CURRENT POPS FOR TRW/RW IN PLACE. && .SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY) ISSUED AT 150 PM MDT FRI MAY 1 2015 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE IN PLACE ACROSS THE SOUTHERN PLAINS WITH WESTERLY FLOW EXTENDING FROM THE GREAT BASIN ACROSS THE CENTRAL ROCKIES AND INTO THE CENTRAL PLAINS. A WEAK SHORTWAVE H5/H7 TROUGH IS IN THE PROCESS OF ROTATING THROUGH THE MEAN FLOW ACROSS THE CENTRAL ROCKIES WITH SHOWER/THUNDERSTORM DEVELOPMENT APPARENT ON UPSTREAM RADARS MOVING EAST OFF THE HIGHER TERRAIN. AT THE SURFACE LOW PRESSURE IS IN PLACE ACROSS THE CWA WITH A STATIONARY FRONT ALONG THE SOUTHEASTERN CORNER OF THE CWA EXTENDING SOUTH IN SOUTHEAST COLORADO. THIS AFTERNOON-TONIGHT...FOCUS CONTINUES TO BE ON POTENTIAL FOR THUNDERSTORMS DEVELOPING OVER THE CWA OR SPREADING EAST INTO THE CWA AS SHORTWAVE MOVES THROUGH THE REGION. WITH FRONT IN PLACE AND AIR MASS DESTABILIZING THERE IS SOME CONCERN THAT ISOLATED THUNDERSTORMS COULD DEVELOP AHEAD OF MAIN SHORTWAVE. HIGH CINH VALUES CURRENTLY IN PLACE ARE INHIBITING CONVECTION CURRENTLY OVER THE CWA DESPITE INCREASING INSTABILITY. AS SHORTWAVE MOVES EAST IT APPEARS THE CAP SHOULD WEAKEN ALLOWING FOR INCREASING CHANCES FROM THE WEST TO THE EAST. BEST PRECIP SIGNAL FROM RAP/HRRR CONTINUES TO BE IN THE SOUTHWEST PART OF THE CWA. 12Z GUIDANCE WAS RUNNING HIGH REGARDING CAPE VALUES MOST OF THE DAY...THOUGH AS SKIES HAVE CLEARED THE LATEST RAP ANALYSIS DOES SHOW 500-1000 KG/J ML CAPE DEVELOPING OVER THE REGION. SHEER IS NOT PARTICULARLY IMPRESSIVE AND AT THIS POINT SEVERE THREAT SEEMS TO BE LIMITED. ANY SHOWER/THUNDERSTORM ACTIVITY SHOULD QUICKLY DISSIPATE OR TRANSITION EAST OF THE CWA THROUGH LATE THIS EVENING AS A SHARP AREA OF SUBSIDENCE MOVES IN BEHIND EXITING SHORTWAVE. SATURDAY...VERY GOOD WAA IS ADVERTISED AND WITH CLEARING SKIES DURING THE FIRST PART OF THE DAY HIGHS SHOULD REACH THE 80S ACROSS THE CWA...POSSIBLY IN THE MID/UPPER 80S IN THE EAST. THE NEXT SHORTWAVE IS SHOWN TO APPROACH THE REGION FROM THE CENTRAL ROCKIES LATE AFTERNOON WITH THUNDERSTORM INITIATION NEAR SURFACE TROUGH ALONG CO/KS BORDER POSSIBLE AFTER 21Z...OTHERWISE BETTER CHANCES ARRIVE LATER IN THE EVENING. MODELS ARE SHOWING VERY UNSTABLE AIR BUILDING OVER THE REGION WITH NAM ADVERTISING 1500-2500 J/KG OF ML CAPE BY LATE AFTERNOON. SHEER IS A LITTLE BETTER THAN TODAY WITH EFFECTIVE SHEER IN EXCESS OF 35KT. WITH THIS IN MIND ANY THUNDERSTORMS THAT DEVELOP LATE TUESDAY AFTERNOON COULD POTENTIALLY ORGANIZE AND BECOME SEVERE. WITH MINIMAL LOW LEVEL SHEER LARGE HAIL/DAMAGING WIND CONTINUE TO BE MAIN CONCERNS. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 226 AM MDT SAT MAY 2 2015 THE LONG TERM FORECAST PERIODS BEGINS WITH AN UPPER LEVEL SHORTWAVE TROUGH THAT TAKES A NEGATIVE TILT INTO THE HIGH PLAINS REGION...WHICH WILL BRING CHANCES FOR SHOWERS AND THUNDERSTORMS TUESDAY. ALTHOUGH A NEGATIVE TILT USUALLY SIGNIFIES STEEP LAPSE RATES ALOFT...IN THIS CASE THE LAPSE RATES ARE NOT TOO IMPRESSIVE WITH VERY LITTLE CAPE IN THE PROFILE. BETWEEN 200 AND 500 J/KG OF CAPE IS PRESENT ACROSS THE AREA TUESDAY AFTERNOON AND EVENING...BUT THAT IS ENOUGH WITH VERY SATURATED FORECAST SOUNDINGS TO PRODUCE EFFICIENT RAINFALL. STRONG SOUTHERLY FLOW THROUGHOUT THE ENTIRE ATMOSPHERIC PROFILE WILL ADVECT MOIST GULF AIR INTO THE REGION WITH PRECIPITABLE WATER AMOUNTS ACROSS THE AREA GREATER THAN ONE INCH...WHICH IS IN THE 99TH PERCENTILE BASED ON CLIMATOLOGY. THEREFORE...INCREASED POP AND QPF VALUES IN THE FORECAST FOR THIS PERIOD WITH THE EXPECTATION OF WIDESPREAD MODERATE RAINFALL...WITH LOCALLY HEAVY AMOUNTS. IN THE EARLY MORNING HOURS WEDNESDAY...GFS SOUNDINGS INDICATE AN INTRUSION OF DRY MID LEVEL AIR...WHICH WILL INCREASE CAPE VALUES IN THE PROFILE HEADING INTO WEDNESDAY AFTERNOON BETWEEN 1000 AND 1800 J/KG....WHICH COULD RESULT IN SOME STRONGER THUNDERSTORMS. SEVERE POTENTIAL DOES NOT LOOK STRONG AT THIS POINT WITH WEAK SURFACE FORCING...MARGINAL SPEED AND DIRECTIONAL SHEAR...AND DISAGREEMENT IN MODEL FORECASTS REGARDING JET POSITION. ALTHOUGH MODELS DISAGREE SLIGHTLY TO THE UPPER LEVEL TROUGH POSITION...TIMING AND PATTERN GENERALLY LINE UP ON THURSDAY AFTERNOON WITH THE UPPER TROUGH GETTING PINCHED OFF FROM THE MAIN FLOW AND BECOMING CUT OFF OVER THE WESTERN THIRD OF THE CONUS. BECAUSE THE LOW WILL BECOME REMOVED FROM THE MAIN UPPER JET FLOW...THE FEATURE WILL SPIN SLOWLY EASTWARD OVER THE HIGH PLAINS REGION PROVIDING CHANCES FOR SHOWERS AND THUNDERSTORMS THURSDAY NIGHT THROUGH FRIDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1115 PM MDT FRI MAY 1 2015 KGLD...VFR THROUGH THE PERIOD. SOUTHWEST WINDS 5-10KTS AT TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH AT SIMILAR SPEEDS AROUND 19Z THEN SOUTHWEST NEAR 10KTS FROM 02Z THROUGH THE REST OF THE TAF PERIOD. THUNDERSTORMS ARE POSSIBLE AROUND OR OVER THE TERMINAL AFTER 02Z THUS VCTS WORDING. KMCK...VFR THROUGH THE PERIOD. LIGHT SOUTHWEST WIND AT TAF ISSUANCE EXPECTED THROUGH THE TAF PERIOD. MAY SEE A FEW SHOWERS FROM TAF ISSUANCE THROUGH 07Z AND VARIABLE WINDS GUSTING 20KTS OR SO POSSIBLE. OTHERWISE...NO PRECIPITATION EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...DR LONG TERM...MK AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1115 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 540 PM MDT FRI MAY 1 2015 UPDATE TO GOING FORECAST TO ACCOUNT FOR VEIL OF MID/HIGH CLOUDS CURRENTLY OVER THE AREA. ALL ACTIVITY EMANATING FROM CONVECTION OFF OVER CENTRAL COLORADO. TREND IS TO CONTINUE EASTWARD THRU THE EVENING HOURS BEFORE DECREASING AFTER MIDNIGHT. HAVE GONE WITH CLOUDY BECOMING PARTLY CLOUDY LATE FOR THE CWA. REST OF FORECAST IS ON TRACK AT THIS TIME. CONVECTION OVER CENTRAL COLORADO IS FINALLY EDGING INTO PORTIONS OF EASTERN COLORADO...SO WILL LEAVE CURRENT POPS FOR TRW/RW IN PLACE. && .SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY) ISSUED AT 150 PM MDT FRI MAY 1 2015 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE IN PLACE ACROSS THE SOUTHERN PLAINS WITH WESTERLY FLOW EXTENDING FROM THE GREAT BASIN ACROSS THE CENTRAL ROCKIES AND INTO THE CENTRAL PLAINS. A WEAK SHORTWAVE H5/H7 TROUGH IS IN THE PROCESS OF ROTATING THROUGH THE MEAN FLOW ACROSS THE CENTRAL ROCKIES WITH SHOWER/THUNDERSTORM DEVELOPMENT APPARENT ON UPSTREAM RADARS MOVING EAST OFF THE HIGHER TERRAIN. AT THE SURFACE LOW PRESSURE IS IN PLACE ACROSS THE CWA WITH A STATIONARY FRONT ALONG THE SOUTHEASTERN CORNER OF THE CWA EXTENDING SOUTH IN SOUTHEAST COLORADO. THIS AFTERNOON-TONIGHT...FOCUS CONTINUES TO BE ON POTENTIAL FOR THUNDERSTORMS DEVELOPING OVER THE CWA OR SPREADING EAST INTO THE CWA AS SHORTWAVE MOVES THROUGH THE REGION. WITH FRONT IN PLACE AND AIR MASS DESTABILIZING THERE IS SOME CONCERN THAT ISOLATED THUNDERSTORMS COULD DEVELOP AHEAD OF MAIN SHORTWAVE. HIGH CINH VALUES CURRENTLY IN PLACE ARE INHIBITING CONVECTION CURRENTLY OVER THE CWA DESPITE INCREASING INSTABILITY. AS SHORTWAVE MOVES EAST IT APPEARS THE CAP SHOULD WEAKEN ALLOWING FOR INCREASING CHANCES FROM THE WEST TO THE EAST. BEST PRECIP SIGNAL FROM RAP/HRRR CONTINUES TO BE IN THE SOUTHWEST PART OF THE CWA. 12Z GUIDANCE WAS RUNNING HIGH REGARDING CAPE VALUES MOST OF THE DAY...THOUGH AS SKIES HAVE CLEARED THE LATEST RAP ANALYSIS DOES SHOW 500-1000 KG/J ML CAPE DEVELOPING OVER THE REGION. SHEER IS NOT PARTICULARLY IMPRESSIVE AND AT THIS POINT SEVERE THREAT SEEMS TO BE LIMITED. ANY SHOWER/THUNDERSTORM ACTIVITY SHOULD QUICKLY DISSIPATE OR TRANSITION EAST OF THE CWA THROUGH LATE THIS EVENING AS A SHARP AREA OF SUBSIDENCE MOVES IN BEHIND EXITING SHORTWAVE. SATURDAY...VERY GOOD WAA IS ADVERTISED AND WITH CLEARING SKIES DURING THE FIRST PART OF THE DAY HIGHS SHOULD REACH THE 80S ACROSS THE CWA...POSSIBLY IN THE MID/UPPER 80S IN THE EAST. THE NEXT SHORTWAVE IS SHOWN TO APPROACH THE REGION FROM THE CENTRAL ROCKIES LATE AFTERNOON WITH THUNDERSTORM INITIATION NEAR SURFACE TROUGH ALONG CO/KS BORDER POSSIBLE AFTER 21Z...OTHERWISE BETTER CHANCES ARRIVE LATER IN THE EVENING. MODELS ARE SHOWING VERY UNSTABLE AIR BUILDING OVER THE REGION WITH NAM ADVERTISING 1500-2500 J/KG OF ML CAPE BY LATE AFTERNOON. SHEER IS A LITTLE BETTER THAN TODAY WITH EFFECTIVE SHEER IN EXCESS OF 35KT. WITH THIS IN MIND ANY THUNDERSTORMS THAT DEVELOP LATE TUESDAY AFTERNOON COULD POTENTIALLY ORGANIZE AND BECOME SEVERE. WITH MINIMAL LOW LEVEL SHEER LARGE HAIL/DAMAGING WIND CONTINUE TO BE MAIN CONCERNS. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 218 PM MDT FRI MAY 1 2015 A FLATTENED RIDGE WILL BE OVER THE SOUTHERN PLAINS THROUGH SUNDAY NIGHT WITH WESTERLY FLOW OVER THE CENTRAL PLAINS. THE SOUTHERN PLAINS RIDGE WILL SHIFT EASTWARD MONDAY WITH SOUTHWEST FLOW OVER THE CENTRAL PLAINS. A SURFACE TROUGH OVER EASTERN COLORADO WILL MIGRATE SLOWLY EAST ACROSS NORTHWEST KANSAS THROUGH SUNDAY NIGHT. SURFACE HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY BEHIND THE EXITING TROUGH. A SHORTWAVE MOVES ACROSS THE FA SATURDAY EVENING WITH SUBSIDENCE INDICATED AFTER 06Z TUESDAY AS THE SHORTWAVE SLIDES SOUTHEAST OUT OF THE AREA. H8-7 LAYER MEAN RH IS NOT IDEAL SO WILL KEEP POPS AT SLIGHT CHANCE. CAPE VALUES UP TO 1000 J/KG ARE EXPECTED WITH AN AREA OF 35 KTS SHEAR OVER NORTHEAST COLORADO. A FEW ISOLATED MARGINALLY SEVERE STORMS ARE POSSIBLE. SUBSIDENCE CONTINUES THROUGH SUNDAY MORNING AND INTO THE AFTERNOON. THE NEXT SHORTWAVE SHOULD IMPACT EASTERN COLORADO BY MID TO LATE AFTERNOON. PLAN TO GO WITH CHANCE POPS OVER WESTERN PORTIONS OF EASTERN COLORADO AND ALSO NEAR THE TROUGH AXIS IN THE SOUTHEASTERN FA. GOOD DYNAMICS AND MOISTURE MOVE ACROSS THE FA SUNDAY NIGHT SO WILL GO WITH HIGHER CHANCE POPS ESPECIALLY IN THE WEST DURING THE EVENING WHERE STORMS SHOULD ALREADY BE IN PROGRESS. HIGH CHANCE POPS WILL CONTINUE AFTER 06Z MONDAY AS THE SHORTWAVE IMPACTS THE ENTIRE AREA. MONDAY DOES NOT APPEAR TO BE AS FAVORABLE FOR PRECIPITATION AS HIGH PRESSURE BUILDING IN FROM THE NORTH PUSHES THE SURFACE BOUNDARY FURTHER SOUTH. FURTHERMORE, THE MAIN SURFACE LOW IS OVER SOUTHERN CALIFORNIA, DYNAMICS ARE MORE UNCERTAIN. CONSEQUENTLY LOWERED POPS SOME BUT STILL KEPT CHANCE POPS OVER THE AREA MONDAY AFTERNOON. MIN TEMPERATURES SHOULD VARY FROM THE UPPER 40S TO THE LOWER 50S SATURDAY AND SUNDAY NIGHTS. MAX TEMPERATURES SHOULD RISE TO THE LOWER TO MID 80S SUNDAY AND THEN COOL TO THE MID 60S TO AROUND 70 MONDAY. IN THE EXTENDED...(TUESDAY THROUGH FRIDAY)...ACTIVE WEATHER IS EXPECTED FOR THIS PART OF THE FORECAST. AN UPPER LEVEL TROUGH OVER THE SW CONUS WILL MOVE NORTHEAST AND PHASE INTO A TROUGH OVER THE PACIFIC NORTHWEST. NUMEROUS SHORTWAVES WILL MOVE THROUGH THE FLOW AND ACROSS THE CENTRAL PLAINS. THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE FA ON A DAILY BASIS THROUGH FRIDAY. MIN TEMPERATURES WILL COOL TO THE UPPER 40S AND LOWER 50S. MAX TEMPERATURES SHOULD RANGE FROM 65 TO 70 TUESDAY WARMING TO THE 70S WEDNESDAY THROUGH FRIDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1115 PM MDT FRI MAY 1 2015 KGLD...VFR THROUGH THE PERIOD. SOUTHWEST WINDS 5-10KTS AT TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH AT SIMILAR SPEEDS AROUND 19Z THEN SOUTHWEST NEAR 10KTS FROM 02Z THROUGH THE REST OF THE TAF PERIOD. THUNDERSTORMS ARE POSSIBLE AROUND OR OVER THE TERMINAL AFTER 02Z THUS VCTS WORDING. KMCK...VFR THROUGH THE PERIOD. LIGHT SOUTHWEST WIND AT TAF ISSUANCE EXPECTED THROUGH THE TAF PERIOD. MAY SEE A FEW SHOWERS FROM TAF ISSUANCE THROUGH 07Z AND VARIABLE WINDS GUSTING 20KTS OR SO POSSIBLE. OTHERWISE...NO PRECIPITATION EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...DR LONG TERM...FS AVIATION...99
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1133 PM CDT Fri May 1 2015 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Saturday) Issued at 333 PM CDT FRI MAY 1 2015 19Z water vapor shows a ridge of high pressure centered over the AZ/NM boarder and broad cyclonic flow from the Gulf of AK through western Canada. Within this pattern, much of the shortwave activity remains along the Canadian boarder. At the surface, a ridge of high pressure was centered over the MS river valley with a weak trough of low pressure from northwest KS through the eastern Dakotas. For tonight and Saturday, there are two potential sources for forcing convection, and confidence in either one is rather so-so. The first is a possible convectively induced vort max (MCV) coming off the central Rockies this evening. The HRRR and RAP have been the most aggressive in holding precip together off the higher terrain and into the forecast area through Saturday morning. These solutions have also be to aggressive in this afternoon`s precip so I don`t know how much weight to put behind this idea with the GFS and NAM shearing out any MCV. At this point, have taken a wait and see approach for the convection to fully move off the mountains. Additionally the MCV may tend to move just southwest of the forecast area. The second forcing mechanism may end up being the low level jet and isentropic lift. The NAM and GFS seem to favor this, developing precip along the NEB state line and moving it into northern MO Saturday morning. However it appears the low level jet will be veered to the southwest with the stronger wind speeds to the west of the area. Additionally theta-e advection is marginal with the low level jet. The models do prog some isentropic lift over far northeast KS which may explain why they are generating precip. Nevertheless confidence is marginal since the low level jet itself is not very strong and moisture advection with the jet is weak. Have kept some 20 to 30 percent POPs across the northern counties through the morning to account for the possibility. Lows tonight should be a little more mild with readings remaining in the lower and mid 50s. Think skies are likely to remain at least partly cloudy with debris clouds spreading in from the west, helping to keep lows in the 50s. Models show some warm air advection through the day Saturday as low level flow remains southerly. Based on 850 temp progs and some insolation through the afternoon, think highs should warm into the upper 70s and lower 80s. .LONG TERM...(Saturday Night through Friday) Issued at 333 PM CDT FRI MAY 1 2015 Increasing low level southerly flow Saturday night into Sunday brings precipitable water values further above normal to near 1.5 inches. Main forcing mechanism approaches Sunday afternoon as a northern branch wave allows a cold front to settle south into the area, likely from southwest Kansas into east central Nebraska. Could see far western locations impacted late in the afternoon as storms could fire not far to the west-southwest, but chances increase in the next few periods as the front ceases its southerly push, between the northern and southern branches. Just how far the front gets is obviously a challenge and will be key for precip potential. Have tapered southern end of precip chances for Sunday night, with best mean chances Monday into Monday night until southerly flow returns to the northwest, ushering the front back north. At this point Tuesday appears the most likely dry period, with a modest but increasingly powerful upper wave rotating northeast into the Plains Tuesday night into Wednesday night. Expect most locations to see at least some precip in this period with deep south flow keeping available moisture plentiful. Beyond this, model differences increase for a much less confidence forecast, though a modified front could be in play with a still warm and moist airmass to support chance PoPs. As for thunderstorm severity, mid/upper flow is not very strong being between the northern and southern branches. With greater confidence in the late weekend/early next week boundary in the vicinity, there will of course be low level shear potential here with ML CAPE likely around 1500 J/kg. In the latter wetter period, the wave`s orientation keeps winds somewhat unidirectional with height, and instability specifics anything but certain with periodic precip quite likely. Expect highs to be generally near to a few degrees above normal, with main problem being depth/persistence of cloud/precip north of the front Monday to bring possibly cooler temps possible in northern areas. && .AVIATION...(For the 06Z TAFs through 06Z Saturday Night) Issued at 1128 PM CDT FRI MAY 1 2015 VFR conditions expected through most of the taf period. Low level wind shear was not well forecasted by the models therefore have added a group based on current observations. The models are also hinting at a shortwave tracking across the area during mid day. An isolated shower or storm could be possible with this feature although confidence was too low at this point to mention. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS DULUTH MN
351 AM CDT SAT MAY 2 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 351 AM CDT SAT MAY 2 2015 VERY WARM THIS WEEKEND WITH A CHANCE FOR SHOWERS AND THUNDERSTORMS THIS EVENING THROUGH SUNDAY AS A COLD FRONT WORKS ITS WAY EAST ACROSS THE REGION. HAVE SOME CONCERNS RELATED TO JUST HOW FAR EAST THE PRECIPITATION MAKES IT TONIGHT...BUT SUNDAY LOOKS FAIRLY WET ACROSS PORTIONS OF NORTHWEST WISCONSIN. TEMPS WILL BE IN THE MID 70S TO NEAR 80 TODAY...WELL ABOVE NORMAL BUT NOT NEARING ANY RECORD HIGHS. COOLER TOMORROW BEHIND THE COLD FRONT. EARLY THIS MORNING PATCHY FOG HAS DEVELOPED IN PORTIONS OF INLAND NORTHEAST TO EAST CENTRAL MINNESOTA...BUT DO NOT EXPECT FOG TO LAST VERY LONG PAST SUNRISE. TODAY...MOSTLY SUNNY AND WARM WITH SOUTHWEST WINDS OF 10 TO 15 MPH. DRY...WITH RELATIVE HUMIDITY FALLING TO 20 TO 30 PERCENT ACROSS MUCH OF NORTH-CENTRAL MINNESOTA. WINDS IN THIS REGION WILL GUST TO OVER 25 MPH AT TIMES DUE TO DEEP MIXING...SEE THE LATEST FIRE WEATHER FORECAST FOR MORE DETAILS WITH REGARD TO FIRE WEATHER RISK. AS A COLD FRONT APPROACHES FROM THE WEST THERE WILL BE INCREASING CLOUDS IN THE FORM OF CU ACROSS NORTH-CENTRAL MINNESOTA....MAINLY FROM LEECH LAKE TO INTERNATIONAL FALLS AND POINTS WEST BY THE LATE AFTERNOON. TEMPERATURES VERY WARM...IN THE MID 70S TO NEAR 80 INLAND...BUT AS COOL AS THE MID 50S TO MID 60S ADJACENT TO LAKE SUPERIOR...WITH COOLER TEMPS MOVING INLAND ACROSS PORTIONS OF THE NORTH SHORE DUE TO SOUTH TO SOUTHEAST WINDS OVER THE LAKE. TONIGHT...A LINE OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS NORTH CENTRAL MINNESOTA EARLY THIS EVENING BUT LIKELY DISSIPATE AS THEY MOVE INTO NORTHEAST MINNESOTA TONIGHT. KEPT POPS GOING OVERNIGHT WHERE THE BEST EML WILL BE LOCATED...BUT THINK DRY AIR AT LOW LEVELS WILL CAUSE THE LINE OF PRECIP TO GENERALLY DISSIPATE BY MIDNIGHT. MOST OF THE CONVECTION-ALLOWING GUIDANCE SUPPORTS THIS SOLUTION...THOUGH SOME OF THE PARAMETERIZED GUIDANCE SUCH AS THE ECMWF DEPICT A MUCH MORE MOIST ENVIRONMENT SUSTAINING PRECIP OVERNIGHT. BELIEVE THIS TO BE DUE TO OVERSATURATION AT MID AND UPPER LEVELS...AND THUS THINK THIS SOLUTION IS OVERDONE. GEM OFFERS A REASONABLE COMPROMISE OF THE AVAILABLE GUIDANCE...SO LEANED TOWARDS THIS FOR THE OVERNIGHT POPS. TEMPS MILD OVERNIGHT DUE TO CLOUDS COVER ALONG/BEHIND THE FRONT AND SW FLOW LEADING TO CONTINUED WAA AHEAD OF THE FRONT...IN THE UPPER 40S NEAR THE LAKE TO LOW/MID 50S MOST LOCATIONS INLAND...WHICH IS 10 TO 20 DEGREES ABOVE NORMAL. SUNDAY...AFTER A LULL IN PRECIP LATE SAT NIGHT ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL DEVELOP. MLCAPE OF 500 TO 1500 WILL BE MORE THAN ENOUGH TO SUPPORT A FEW STRONG THUNDERSTORMS...WITH SMALL HAIL AND GUSTY WINDS THE MAIN THREAT. PWAT VALUES WILL BE ABOVE NORMAL AT JUST OVER AN INCH ACROSS NORTHWEST WISCONSIN...WITH A TALL AND SKINNY CAPE PROFILE SUPPORTING THE POSSIBILITY OF MODERATE TO LOCALLY HEAVY RAINFALL...WITH SOME LOCATIONS REVIVING OVER A HALF INCH OF RAINFALL SUNDAY AFTERNOON. HIGH TEMPS COOLER...IN THE LOW TO MID 70S. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 351 AM CDT SAT MAY 2 2015 THE COLD FRONT WILL PASS OVER WISCONSIN SUNDAY EVENING...EXITING TO THE EAST BY MIDNIGHT. SCATTERED STORMS WILL BE LIKELY IN THE HAYWARD TO PARK FALLS AREA DURING THE EVENING HOURS. SFC HIGH PRESSURE WILL BUILD OVER MN LATE SUNDAY NIGHT...CENTERING OVER THE WESTERN LAKE SUPERIOR REGION MONDAY. MODELS ARE IN GOOD AGREEMENT THAT A VORT MAX TRANSLATES ALONG THE INTERNATIONAL BORDER SUNDAY NIGHT/MONDAY...ALLOWING FOR COOLING TEMPS ALOFT AND H85 TEMPERATURES TO DIP INTO THE SINGLE DIGITS MONDAY. ALTHOUGH HIGH TEMPS WILL BE SLIGHTLY COOLER /IN THE 60S MONDAY/...THE DRY AIR MASS AND STEEP LAPSE RATES WILL PROMOTE DEEP MIXING AND LOW RH VALUES AROUND 20 PERCENT. WINDS WILL GENERALLY BE OUT OF THE NORTHWEST TO NORTH WITH AFTERNOON GUSTS AROUND 15 MPH. FOCUS TURNS TO LONG WAVE TROUGH IN THE PACIFIC NORTHWEST...THAT EJECTS A SHORT WAVE INTO THE UPPER PLAINS MID-WEEK. THE WAVE WILL LIFT A WARM FRONT ACROSS THE NORTHLAND TUESDAY NIGHT/WEDNESDAY...BRINGING A TRANSITION TO GUSTY SOUTHERLY WINDS /EXCEPT EAST NEAR LAKE SUPERIOR/ AND INCREASING MOISTURE. LONG RANGE MODELS SHOW A TREND TOWARDS A WET PERIOD AS THE WAVES ORGANIZES INTO A SFC LOW OVER THE DAKOTAS WED NIGHT...AND SLOWLY MIGRATES EAST ACROSS MINN THROUGH THE END OF THE WEEK. THE PROLONGED PERIOD OF RETURN FLOW AND SLOW MOVING LOW PRESSURE SYSTEM WILL BRING THE POTENTIAL FOR WIDESPREAD, LONG DURATION, RAINFALL ACROSS MUCH OF THE FORECAST AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 100 AM CDT SAT MAY 2 2015 VFR CONDITIONS EXPECTED AT ALL TERMINALS THROUGH THE FORECAST PERIOD. WINDS WILL BECOME VERY LIGHT TONIGHT. THE LATEST 00Z GUIDANCE ALONG WITH THE LAST SEVERAL HRRR RUNS HAVE BACKED OFF ON FOG DEVELOPING AT KDLH AND KHIB. FELT CONFIDENT ENOUGH TO KEEP FOG OUT OF THE FORECAST. RIDGING WILL OCCUR OVER THE MID ATLANTIC ON SATURDAY...THIS WILL ALLOW SSW WINDS TO DEVELOP AT ALL TERMINALS. DAY TIME HEATING ALONG WITH VERY DRY AIR IN THE LOWER LEVELS WILL ALLOW GUSTY WINDS TO DEVELOP DURING THE AFTERNOON AT ALL SITES EXCEPT FOR KHYR. LATE SATURDAY AFTERNOON A COLD FRONT WILL MOVE INTO WESTERN MINNESOTA FROM THE DAKOTAS. THIS WILL ALLOW SHOWERS AND PERHAPS A FEW THUNDERSTORMS TO DEVELOP. STILL UNCERTAIN ON THE EXTENT OF THE THUNDERSTORM ACTIVITY...SO KEPT VCSH AT KINL AND KBRD. && .PRELIMINARY POINT TEMPS/POPS... DLH 73 52 72 43 / 10 20 50 0 INL 80 49 72 38 / 20 20 20 0 BRD 77 54 73 43 / 10 30 40 0 HYR 75 54 75 43 / 10 0 80 20 ASX 76 51 75 43 / 10 10 80 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING FOR MNZ010-018-025-026. WI...NONE. LS...NONE. && $$ SHORT TERM...JJM LONG TERM...GRANING AVIATION...GRANING/WL
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
101 AM CDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 401 PM CDT FRI MAY 1 2015 WEAKENING FRONTAL ZONE CURRENTLY BISECTING THE DULUTH CWA FROM SW TO NE SHOULD SLOWLY WASH OUT OVERNIGHT TONIGHT AS THE PARENT WAVE IN ONTARIO CONTINUES TO PULL AWAY FROM THE REGION AND WEAKEN. A FAIR AMOUNT OF BOUNDARY LAYER CUMULUS HAS DEVELOPED THIS AFTERNOON FROM THE BRAINERD AREA NEWD TO THE MN ARROWHEAD..SO A FEW ISOLATED SHOWERS CANNOT BE RULED OUT WITHIN THE WEAKENING FRONTAL ZONE ACROSS EASTERN MN/THE ARROWHEAD/NW WISCONSIN. HOWEVER..WE EXPECT ANY SHOWERS..IF THEY OCCUR AT ALL..TO BE QUITE SHORT LIVED. WEAK LOW LEVEL RIDGING WILL TAKE HOLD OVERNIGHT..WITH CLEARING SKIES AND LIGHT WINDS. TEMPS SHOULD BE ABLE TO DROP FAIRLY RAPIDLY..ESPECIALLY IN AREAS THAT CLEAR SOONER. SOME AREAS OF FOG ARE ALSO EXPECTED OVERNIGHT OVER THE EASTERN HALF OF THE CWA. THE MAIN CONCERN ON SATURDAY WILL BE THE CRITICAL FIRE WEATHER CONDITIONS THAT ARE EXPECTED TO DEVELOP..ESPECIALLY ACROSS THE NW PARTS OF THE CWA. WHILE THE STRONGEST S/SW WINDS ARE EXPECTED TO REMAIN TO THE WEST OF OUR AREA ACROSS THE RED RIVER VALLEY..TEMPS SHOULD RISE TO NEAR THE WARMEST READINGS OF THE SPRING SO FAR.. WITH UPPER 70S OR EVEN LOWER 80S OVER THE WESTERN QUARTER TO THIRD OF THE CWA. MOISTURE RETURN WILL BE MEAGER AHEAD OF THE NEXT SYSTEM..AT LEAST INITIALLY..AND WITH VEGETATION STILL NOT IN A ROBUST GREEN UP STATE..BOUNDARY LAYER MOISTURE SHOULD PLUMMET TO HUMIDITY VALUES LESS THAN 20 PERCENT IN MANY AREAS SAT AFTERNOON/EVENING OUT WEST. WE COORDINATED A FIRE WEATHER WATCH WITH THE FGF OFFICE AND MIFC FOR KOOCHICHING/ITASCA AND NORTHERN CASS COUNTIES FROM 11 AM THROUGH 8 PM SATURDAY. A FEW SHOWERS/TSTORMS SHOULD INITIATE OVER ERN ND WITH THE NEXT FRONT SAT EVENING..BUT ANY PRECIP SHOULD TAKE UNTIL WELL AFTER 00Z SAT EVENING TO REACH NCENT MN. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 401 PM CDT FRI MAY 1 2015 A COLD FRONT WILL MOVE WNW TO ESE ACROSS NE MINNESOTA AND NW WISCONSIN SUNDAY. MOST OF THE MODELS CONTINUE TO INDICATE THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS WITH THE PASSING FRONT. THE HIGHEST CHANCES FOR SHOWERS AND STORMS IS NW WISCONSIN DURING THE AFTERNOON AND EVENING OF SUNDAY. THIS IS ALSO WHERE THERE COULD BE STRONG TO NEARLY SEVERE THUNDERSTORMS. AT THIS TIME...IT APPEARS THERE WILL BE SUFFICIENT INSTABILITY AND WIND SHEAR TO SUPPORT STRONG TO SEVERE THUNDERSTORMS. THE PRECIPITABLE WATER VALUES WILL CLIMB TO NEARLY 1.5 INCHES IN THE SE FORECAST AREA...SO NW WISCONSIN COULD ALSO GET HEAVY RAIN. HIGH PRESSURE WILL MOVE INTO THE NORTHLAND EARLY NEXT WEEK...PROVIDING WARM AND DRY WEATHER MONDAY AND TUESDAY. THE GFS/GEM/ECMWF CONTINUE TO INDICATE THAT A LOW PRESSURE IN THE HIGH PLAINS NEAR COLORADO WILL LIFT INTO THE NORTHERN PLAINS AND CANADA WEDNESDAY AND THURSDAY. THE WARM FRONT ASSOCIATED WITH THE LOW PRESSURE WILL LIFT INTO THE NORTHERN PLAINS AND UPPER MIDWEST. THE NORTHLAND WILL SEE A PERIOD OF WARM AND MORE HUMID SOUTHERLY FLOW WITH AN EXTENDED PERIOD OF HIGHER CHANCES OF SHOWERS AND THUNDERSTORMS FOR WEDNESDAY THROUGH AT LEAST THURSDAY. THE RAINS COULD BRING RELIEF TO DROUGHT STRICKEN MINNESOTA AND WISCONSIN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 100 AM CDT SAT MAY 2 2015 VFR CONDITIONS EXPECTED AT ALL TERMINALS THROUGH THE FORECAST PERIOD. WINDS WILL BECOME VERY LIGHT TONIGHT. THE LATEST 00Z GUIDANCE ALONG WITH THE LAST SEVERAL HRRR RUNS HAVE BACKED OFF ON FOG DEVELOPING AT KDLH AND KHIB. FELT CONFIDENT ENOUGH TO KEEP FOG OUT OF THE FORECAST. RIDGING WILL OCCUR OVER THE MID ATLANTIC ON SATURDAY...THIS WILL ALLOW SSW WINDS TO DEVELOP AT ALL TERMINALS. DAY TIME HEATING ALONG WITH VERY DRY AIR IN THE LOWER LEVELS WILL ALLOW GUSTY WINDS TO DEVELOP DURING THE AFTERNOON AT ALL SITES EXCEPT FOR KHYR. LATE SATURDAY AFTERNOON A COLD FRONT WILL MOVE INTO WESTERN MINNESOTA FROM THE DAKOTAS. THIS WILL ALLOW SHOWERS AND PERHAPS A FEW THUNDERSTORMS TO DEVELOP. STILL UNCERTAIN ON THE EXTENT OF THE THUNDERSTORM ACTIVITY...SO KEPT VCSH AT KINL AND KBRD. && .PRELIMINARY POINT TEMPS/POPS... DLH 51 72 43 66 / 10 50 0 0 INL 51 70 38 67 / 30 10 0 0 BRD 54 73 43 70 / 30 50 0 0 HYR 54 75 43 69 / 0 70 30 0 ASX 53 74 43 69 / 0 60 20 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...FIRE WEATHER WATCH FROM 11 AM CDT THIS MORNING THROUGH THIS EVENING FOR MNZ010-018-025-026. WI...NONE. LS...NONE. && $$ AVIATION...GRANING/WL
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1156 PM CDT FRI MAY 1 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 242 PM CDT FRI MAY 1 2015 WEAK HIGH PRESSURE OVERHEAD WILL PIVOT MOISTURE NORTHWARD THIS EVENING. THE RAP AND HRRR SUGGEST WEAKLY ORGANIZED DISCRETE SHOWER AND THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON AND THIS EVENING. OTHER THAN GUSTY OUTFLOW WINDS...NO SIGNIFICANT WEATHER IS EXPECTED AND NO STORMS SHOULD REACH SEVERE LIMITS. A WARM FRONT WILL LIFT NORTH AS THE HIGH MOVES EAST LATER THIS EVENING. DEW POINTS SHOULD INCREASE TO AROUND 50F BY MID SATURDAY MORNING. THE NAM CONTINUES TO ADVERTISE A FAIRLY ROBUST DRYLINE SURGE SATURDAY AFTN FOCUSED ALONG HIGHWAY 20 WEST OF VALENTINE. DESTABILIZATION IS POSSIBLE ACROSS PINE RIDGE AND THE WRN SANDHILLS SOUTH THROUGH IMPERIAL AROUND 21Z. THE NAM DID SHOW ABOUT 20 TO 30 J/KG OF INHIBITION SO POPS ARE ISOLATED. MLCAPE NEAR 1500 J/KG AND BULK SHEAR TO 450 MB OF 30 TO 35 KT COULD SUPPORT AN ISOLATED STRONG OR SEVERE STORM DURING THE PEAK HEATING PERIOD. THE BULK RICHARDSON NUMBER IS CLOSE TO 50 AT THIS TIME AND SHEAR PROFILES LOOK SMOOTHLY CURVED. LOWS TONIGHT FALL TO THE UPPER 40S TO AROUND 50. HIGHS SATURDAY RISE INTO THE LOW TO MID 80S WITH MIXING HEIGHTS NEAR 700 MB. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 242 PM CDT FRI MAY 1 2015 A TRAJECTORY FROM THE PACIFIC SOUTHWEST CONTINUES SATURDAY NIGHT WHILE A TRAJECTORY FROM THE TEXAS GULF COAST CROSSES CENTRAL AND EASTERN NEBRASKA. THE PACIFIC MOISTURE WILL THUS BE IN PLACE WHEN A SURFACE FRONT COMES THROUGH SUNDAY MORNING. THE TIMING OF THE FRONT IS NOT REAL FAVORABLE FOR THUNDERSTORMS. HOWEVER...THE LIFT SHOULD BE SUFFICIENT TO TRIGGER ISOLATED CONVECTION BY SUNDAY EVENING WITH IT CONTINUING SUNDAY NIGHT AND MONDAY IN CENTRAL AND SOUTHWEST NEBRASKA. WITH THE FRONT BECOMING STATIONARY ACROSS CENTRAL KANSAS...SOME UPGLIDE WILL CONTINUE INTO MONDAY AFTERNOON AND EVENING. THIS CAN BE SEEN WITH THE PRESSURE LEVELS AND MOISTURE TRANSPORT VECTORS OVER CENTRAL...SOUTH CENTRAL AND SOUTHWEST NEBRASKA ON THE 300K AND 305K SURFACES. THE INSTABILITY...AT ABOUT 0C FOR THE 800MB BASED LIFTED INDEX...IS EXPECTED TO BE MARGINAL. AS A RESULT...ONLY A FEW EMBEDDED THUNDERSTORMS ARE EXPECTED IN AN AREA OF GENERAL RAIN OR SHOWERS. WITH PRECIPITABLE WATER EXCEEDING 0.7 INCH...SIGNIFICANT PRECIPITATION TOTALS CAN BE EXPECTED ALONG A BROKEN BOW-NORTH PLATTE-IMPERIAL LINE AND SOUTH WITH AMOUNTS DROPPING OFF SHARPLY NORTH OF THAT LINE. AS THE ACTIVE UPPER PATTERN CONTINUES...ANOTHER NEGATIVELY TILTED TROUGH PIVOTS ACROSS THE NORTHERN PLAINS. AHEAD OF THE SYSTEM...A GOOD MOISTURE TRAJECTORY CONTINUES TUESDAY NIGHT AND WEDNESDAY FROM THE TEXAS GULF COAST INTO NEBRASKA AND THE DAKOTAS. AS THE CYCLONE MAKES ITS WAY NORTHWARD...WARM ADVECTION ALOFT WILL CONTINUE BRINGING WIDESPREAD RAINFALL TO WESTERN NEBRASKA. BY EARLY THURSDAY...THE DRY INTRUSION OVERTAKES THE CYCLONE AND BRINGS AN END TO THE PRECIPITATION IN CENTRAL AND WESTERN NEBRASKA. THERE IS SIGNIFICANT DISAGREEMENT BETWEEN THE 00Z ECMWF AND THE 12Z GFS40 WITH THIS SYSTEM...SO CONFIDENCE IS NOT HIGH IN THE SOLUTIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1155 PM CDT FRI MAY 1 2015 VFR CONDITIONS FOR THE KLBF AND KVTN TERMINALS THE NEXT 24 HRS. ISOLATED THUNDERSTORMS NORTH OF THE KLBF TERMINAL ATTM SHOULD REAMIN OUTSIDE THE VICINITY THROUGH 08Z. OTHERWISE SKIES TO BECOME MOSTLY CLEAR OVERNIGHT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...SPRINGER AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1159 PM CDT FRI MAY 1 2015 .UPDATE... ISSUED AT 1159 PM CDT FRI MAY 1 2015 LATEST REGIONAL RADAR AND BOWMAN RADAR SHOWS SOME MID LEVEL RETURNS OVER MILES CITY. THE HRRR 1KM SLICE AND COMPOSITE REFLECTIVITY PICKS UP ON THIS AREA AND TRIES TO DEVELOP AN ISOLATED SHOWER OR TWO THROUGH 10Z ACROSS THE SOUTHWEST. CLOUD BASES APPEAR AROUND 15KFT CURRENTLY...AND WITH THE FAIRLY QUICK SPEED IN THE ECHOES AND MINIMAL AREAL COVERAGE...AT BEST A SPRINKLE OR BRIEF WIND GUST MAY OCCUR. OTHERWISE TEMPERATURES COOLING INTO THE MID 40S AT DICKINSON AND GLEN ULLIN...SO HAVE ADJUSTED HOURLY TEMPS DOWN A BIT QUICKER. OVERNIGHT LOWS ALREADY HAD THEM IN THE LOWER 40S AND WITH PASSING CLOUDS OVERNIGHT THIS REMAINS ON TRACK. MAIN CONCERN WILL BE FIRE WEATHER SATURDAY AND WILL LOOK MORE CLOSELY AT THIS IN THE NEXT UPDATE. UPDATE ISSUED AT 924 PM CDT FRI MAY 1 2015 THE FORECAST FOR THE OVERNIGHT REMAINS ON TRACK...WITH A RELATIVELY MILD NIGHT EXPECTED WITH LOWS IN THE MID TO UPPER 40S WITH LIGHT SOUTHERLY FLOW AHEAD OF THE PRE-FRONTAL TROUGH ACROSS EASTERN MONTANA. UPDATE ISSUED AT 714 PM CDT FRI MAY 1 2015 QUICK UPDATE TO EXPIRE THE RED FLAG WARNING ON TIME. NO OTHER CHANGES NEEDED OTHER THAN TO BLEND TO OBSERVED TRENDS TROUGH 00 UTC. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 255 PM CDT FRI MAY 1 2015 CURRENT SURFACE ANALYSIS PLACES LOW OVER SOUTHERN ALBERTA WITH WARM SOUTHWESTERLY FLOW OVER OUR AREA. UPPER LEVEL ANALYSIS PLACES FLAT RIDGE OVER THE ROCKIES INTO THE PLAINS WITH WESTERLY FLOW OVER THE NORTHERN PLAINS BRINGING QUIET WEATHER TO THE AREA. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...BREEZY CONDITIONS OVER THE WEST AND NORTH CENTRAL WILL SUBSIDE THIS EVENING. OTHERWISE...QUIET WEATHER EXPECTED. ON SATURDAY...SURFACE LOW SLIDES EAST ACROSS SOUTHERN SASKATCHEWAN/MANITOBA...WHILE A COLD FRONT PUSHES ITS WAY INTO WESTERN/CENTRAL NORTH DAKOTA. EXPECT GUSTY WINDS TO DEVELOP AHEAD OF AND ALONG THE FRONT IN REGION OF STRONG MIXING/STEEP LAPSE RATES. GUSTY WINDS WILL ALSO CONTINUE AFTER FRONTAL PASSAGE. A FEW THUNDERSTORMS MAY DEVELOP OVER SOUTH CENTRAL NORTH DAKOTA INTO THE JAMES RIVER VALLEY WHERE MODEST INSTABILITY IS NOTED...THOUGH NOT MUCH IN THE WAY OF PRECIPITATION EXPECTED GIVEN THE DRY LOW LEVELS THOUGH THIS MAY BE CONDUCIVE TO STORMS POSSIBLY DEVELOPING STRONG WIND GUSTS. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 255 PM CDT FRI MAY 1 2015 THE LONG TERM FORECAST IS DOMINATED BY A WEST COAST TROUGH THAT IS FORECAST TO BECOME PHASED WITH THE EASTERN PACIFIC CUT OFF LOW NEAR 160W IN CURRENT SATELLITE IMAGERY. REMAINING SHORTWAVE ENERGY FROM THE CUT OFF LOW IS THEN FORECAST TO EJECT INTO THE NORTHERN PLAINS BY SATURDAY. MODELS/ENSEMBLES HAVE BEEN FAIRLY CONSISTENT WITH THIS FEATURE OVER THE PAST COUPLE DAYS...AND THE STRONG MID LEVEL DYNAMICS ASSOCIATED WITH THE WAVE SUPPORT SOME OF THE HIGHER PRECIPITATION CHANCES SEEN IN THE REGION FOR SOME TIME. AT THIS POINT...THERE IS NO INDICATION OF WHETHER STORMS WILL BECOME SEVERE...BUT THAT IS CERTAINLY A POSSIBILITY AS SUCH DYNAMICALLY FORCED SYSTEMS ARE TYPICALLY ACCOMPANIED BY AT LEAST SOME SEVERE WEATHER DURING SPRING MONTHS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1159 PM CDT FRI MAY 1 2015 VFR CIGS/VSBYS NEXT 24HR. A COLD FRONT WILL MOVE INTO WESTERN NORTH DAKOTA BETWEEN 12Z-15Z SATURDAY...THEN TRANSLATE INTO CENTRAL NORTH DAKOTA SATURDAY AFTERNOON...21Z-00Z. EXPECTED A WIND SHIFT FROM SOUTHWEST TO WEST/NORTHWEST. A VCTS WILL BE MENTIONED AT KMOT AND KJMS SATURDAY AFTERNOON. && .FIRE WEATHER... ISSUED AT 255 PM CDT FRI MAY 1 2015 CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE OVER MANY PARTS OF WESTERN AND NORTH CENTRAL NORTH DAKOTA THROUGH THIS AFTERNOON. ON SATURDAY...CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE ACROSS ALL OF NORTH DAKOTA WITH LOW RELATIVE HUMIDITY VALUES AND GUSTY SOUTHWEST WINDS. WINDS WILL START TO SWITCH TOWARDS THE NORTHWEST IN THE WEST AND CENTRAL AS A COLD FRONT MOVES INTO THE AREA. ISOLATED THUNDERSTORMS WILL BE POSSIBLE ACROSS PORTIONS OF THE AREA. LOW RELATIVE HUMIDITY VALUES ARE EXPECTED FOR THE BEGINNING OF NEXT WEEK WITH OCCASIONAL BREEZY CONDITIONS. CONDITIONS WILL BE MONITORED TO SEE IF FURTHER HEADLINES WILL BE NEEDED. DAILY CHANCES FOR WETTING RAINS WILL COME TOWARDS THE MIDDLE OF NEXT WEEK. && .BIS WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM 11 AM CDT /10 AM MDT/ SATURDAY THROUGH SATURDAY EVENING FOR NDZ001>005-009>013-017>023-025-031>037- 040>048-050-051. && $$ UPDATE...KS SHORT TERM...JJS LONG TERM...SCHECK AVIATION...KS FIRE WEATHER...JJS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
147 AM EDT SAT MAY 2 2015 .SYNOPSIS... AN UPPER LEVEL LOW PRESSURE SYSTEM WILL PROGRESS EASTWARD...OUT OF THE REGION OVERNIGHT. HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND AND BE POSITIONED ACROSS OUR REGION INTO MUCH OF NEXT WEEK. OUR NEXT BEST CHANCE OF PRECIPITATION WILL COME DURING THE MIDDLE OF NEXT WEEK WHEN A BACKDOOR COLD FRONT APPROACHES OUR AREA. && .NEAR TERM /THROUGH TODAY/... AS OF 908 PM EDT FRIDAY... UPPER LOW WILL DRIFT EAST INTO THE ATLANTIC OCEAN OVERNIGHT AND SATURDAY. A BROAD RIDGE OF HIGH PRESSURE WILL BUILD EAST FROM THE OHIO VALLEY FOR SATURDAY. KFCX WSR-88D AT 01Z SHOWED SOME ISOLATED CONVECTION DROPPING SOUTH ACROSS EASTERN PORTIONS OF FORECAST AREA. THIS EVENING 00Z RNK SOUNDING SHOWED THE DRIER AIR PUSHING AROUND 700 MB WITH A NORTHERLY FLOW AND PWAT AT 0.46 IN. THE NAM...HRRR...RNK WRFARW AND HIRESW-ARW SUPPORT THE MENTION OF ISOLATED SHOWERS TONIGHT UNTIL AROUND 06Z...MAINLY EAST OF THE BLUE RIDGE MOUNTAINS. PATCHES OF FOG WILL DEVELOP OVERNIGHT ESPECIALLY WHERE IT RAIN FRIDAY. LOW TEMPERATURES OVERNIGHT WILL RANGE FROM AROUND 40 DEGREES IN THE NORTHWEST MOUNTAINS TO THE MID TO UPPER 40S IN THE PIEDMONT. HAVE A GOOD NIGHT. AS OF 555 PM EDT FRIDAY... ADJUSTED TEMPERATURES DOWN IN RAIN COOLED LOCATIONS AND BLEND LAMP TEMPERATURES INTO THE OVERNIGHT. MODIFIED POPS AND WEATHER WITH LATEST WSR-88D TRENDS AND SHAPED POPS THIS EVENING INTO TONIGHT TOWARDS A BLEND OF THE HRRR AND THE RNK WRFARW. AS THE UPPER LOW PUSHES EAST...AREAL COVERAGE OF CONVECTION WILL DIMINISH AND EXIT THE REGION. PATCHES OF FOG WILL DEVELOP ESPECIALLY WHERE IT RAIN THIS AFTERNOON AND THIS EVENING AND CONTINUE INTO THE OVERNIGHT. HELD ON TO THE THE OVERNIGHT LOW TEMPERATURES FROM AROUND 40 DEGREES IN THE NORTHWEST MOUNTAINS TO THE UPPER 40S IN THE PIEDMONT. AS OF 300 PM EDT FRIDAY... AN AREA OF SHOWERS WITH A FEW THUNDERSTORMS CONTINUES TO EXPAND IN COVERAGE BETWEEN ROUGHLY HOT SPRINGS AND BLACKSBURG VA. THE PRECIPITATION WAS EXPANDING TOWARDS THE S-SW. HEADING INTO THIS EVENING...THE REGION OF PRECIPITATION WILL GRADUALLY MAKE PROGRESS EASTWARD...IN PACE WITH THE PROGRESSION OF THE RESPONSIBLE UPPER LEVEL LOW PRESSURE SYSTEM. COVERAGE WILL START TO DECREASE AT SUNSET...WITH THE LAST SHOWERS EXITING THE AREA OR DISSIPATING AROUND 11PM BETWEEN DANVILLE AND LYNCHBURG. CLOUD COVER WILL BE ON THE DECREASE THE REMAINDER OF THE NIGHT. PATCHY LIGHT RIVER VALLEY FOG WILL BE POSSIBLE...AND ALSO IN VALLEYS THAT RECEIVED PRECIPITATION THIS AFTERNOON OR EVENING. LOW TEMPERATURES WILL RANGE FROM AROUND 40 TO THE MID 40S ACROSS THE MOUNTAINS...WITH MID 40S TO UPPER 40S ACROSS THE PIEDMONT. ON SATURDAY...HIGH PRESSURE WILL START TO WORK ITS WAY INTO THE REGION FROM THE WEST. ONE LATE SHORTWAVE TROUGH ROUNDING THE BACKSIDE OF THE DEPARTING UPPER LOW IS EXPECTED TO MOVE SOUTH THROUGH CENTRAL VIRGINIA AND NORTH CAROLINA TOMORROW AFTERNOON. THIS FEATURE PASSING AT THE TIME OF PEAK HEATING MAY HELP TO GENERATE SOME ISOLATED SHOWERS...GENERALLY ALONG AND EAST OF A LEXINGTON VA TO REIDSVILLE NORTH CAROLINA LINE. THANKS TO BUILDING HEIGHTS AND LESS CLOUD COVER...ANTICIPATE A MILDER DAY ON SATURDAY AS COMPARED TO TODAY. HIGHS ACROSS THE MOUNTAINS WILL RANGE FROM THE MID 60S TO NEAR 70 DEGREES...WITH LOW TO MID 70S ACROSS THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH MONDAY/... AS OF 315 PM EDT FRIDAY... 500 MB HEIGHTS GRADUALLY RISE SATURDAY NIGHT AND SUNDAY AS THE PATTERN BECOMES MORE ZONAL. BUFKIT DATA FOR SUNDAY IN THE SOUTHWEST COUNTY WARNING AREA SHOWED A LARGE ENOUGH LOW LEVEL LAPSE RATE AND A LAYER OF MOISTURE THAT WOULD SUPPORT SHOWERS ISOLATED THUNDERSTORMS. HOWEVER...THERE WILL ONLY BE MINIMAL LIFT FROM ANY VORTICITY SO COVERAGE WILL BE CONFINED TO AREAS WITH THE BEST HEATING AND INSTABILITY. AIR MASS WARMS THROUGH THE PERIOD AND WILL BE CLOSE TO +10 TO +12 VALUES AT 850 MB BY THE END OF THE DAY ON MONDAY. THIS WILL PUT MAXIMUM TEMPERATURES JUST ABOVE NORMAL MONDAY. HIGH PRESSURE WILL BE OVER THE AREA SATURDAY NIGHT AND SUNDAY. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 125 PM EDT FRIDAY... LONG WAVE PATTERN ADVERTISED BY MODELS SHOWED TROFING IN THE WESTERN UNITED STATES AND A BROAD SOUTHEAST U.S. RIDGE. A SURFACE COLD FRONT THE THE NORTHERN STREAM WILL BE OVER THE GREAT LAKES ON MONDAY AND WILL PUSH SOUTH AS A BACKDOOR FRONT OVER THE MID ATLANTIC REGION TUESDAY AND WEDNESDAY. QUESTIONABLE HOW FAR SOUTH THIS BOUNDARY GETS HEADING INTO A LARGE RIDGE OVER THE SOUTHEAST. BEST PROBABILITY OF PRECIPITATION WILL BE IN THE VICINITY OF THIS BOUNDARY. OTHERWISE THE CHANCE WILL BE LIMITED TO AIRMASS TYPE THUNDERSTORMS...MAINLY IN THE MOUNTAINS EACH AFTERNOON AND EVENING. MAXIMUM/MINIMUM TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE NORMAL TUESDAY THROUGH FRIDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 135 AM EDT SATURDAY... GENERALLY IMPROVING FLT CONDITIONS WILL CONTINUE OVERNIGHT AS THE SURFACE/UPPER LOW CONTINUE TO MOVE EAST OF THE AREA. PSBL GROUND FOG IN SOME AREAS OVERNIGHT...BUT SO FAR VERY IT HAS BEEN PATCHY...WENT WITH MVFR FOR A PERIOD AT DAN/LWB/BCB AND IFR AT LYH WHERE IT SEEMS TO BE DEVELOPING EARLIER. AFTER 14Z SAT...EXPECT VFR CONDITIONS AREA WIDE. WINDS LIGHT AND MOSTLY NW THROUGH THE TAF VALID PERIOD ON THE BACK SIDE OF THE UPPER LOW...BUT SOME VARIABLE WINDS THIS EVENING. AT ANY RATE...SPEEDS MOSTLY 7KTS OR LESS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN VSBYS THROUGH 14Z...THEN HIGH CONFIDENCE IN VFR VSBYS AT ALL TAF SITES. MEDIUM CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD. NOTE...THE VISIBILITY SENSOR AT THE ASOS AT KBLF CONTINUES TO MALFUNCTION. WILL CONTINUE WITH AMD NOT SKED APPENDED TO ITS TAF. EXTENDED AVIATION DISCUSSION... OTHER THAN SOME PATCHY LATE NIGHT/EARLY MORNING RIVER VALLEY FOG IN THE TYPICAL LOCATIONS...VFR CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. SCATTERED AFTERNOON SHOWERS COULD AFFECT THE MOUNTAINS TUE...BUT MORE LIKELY WED-THU AS A BACK DOOR FRONT DRIFTS TOWARD THE REGION. HIGH PRESSURE ALOFT WILL NOT PROVIDE MUCH IN THE WAY OF ANY SYNOPTIC-SCALE FORCING THROUGH THE PERIOD THOUGH. && .EQUIPMENT... AS OF 907 PM EDT FRIDAY... THE VISIBILITY SENSOR AT THE BLUEFIELD...KBLF...ASOS MAY ALTERNATE BETWEEN AVAILABLE AND UNAVAILABLE UNTIL SUCH TIME APPROPRIATE CORRECTIVE MEASURES CAN BE COMPLETED. THE NOAA WEATHER RADIO AT ROANOKE VIRGINIA...WXL60...WHICH BROADCASTS AT A FREQUENCY OF 162.475 MHZ...IS BACK ON THE AIR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/KK SHORT TERM...AMS/RAB LONG TERM...AMS AVIATION...DS/PC EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1106 PM MDT FRI MAY 1 2015 .UPDATE... ISSUED AT 959 PM MDT FRI MAY 1 2015 WE HAVE ADDED AREAS OF DENSE FOG THROUGH AROUND 1 AM FOR THE INTERSTATE 80 SUMMIT BETWEEN LARAMIE AND CHEYENNE AS WELL AS OVER THE WESTERN FOOTHILLS OF LARAMIE COUNTY BASED ON WEBCAMS. WE BELIEVE THE FOG WILL QUICKLY DISSIPATE BETWEEN MIDNIGHT AND 3 AM AS THE BOUNDARY LAYER WINDS BECOME WEST. UPDATE ISSUED AT 932 PM MDT FRI MAY 1 2015 GRIDDED FORECASTS UPDATED TO REMOVE SHOWERS AND THUNDERSTORMS FOR THE REST OF THE NIGHT AND TO ADJUST TEMPERATURES...DEWPOINTS...WINDS AND CLOUD COVER FOR THE REST OF THE NIGHT. UPDATE ISSUED AT 602 PM MDT FRI MAY 1 2015 OUR GRIDDED FORECASTS HAVE BEEN UPDATED PRIMARILY TO ACCOUNT FOR SPATIAL COVERAGE OF SHOWERS AND THUNDERSTORMS...OVER EASTERN LARAMIE COUNTY OF WYOMING...AND OVER KIMBALL AND WESTERN CHEYENNE COUNTIES OF NEBRASKA. HAVE TOUCHED UP OTHER METEOROLOGICAL VARIABLES FOR THE REST OF THE NIGHT BASED ON TRENDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 354 PM MDT FRI MAY 1 2015 SHOWERS AND THUNDERSTORMS ARE ON THE UPTICK ALONG THE INTERSTATE 80 CORRIDOR IN SOUTHEAST WY THIS AFTERNOON. AS EXPECTED...THE GREATEST COVERAGE HAS BEEN IN ALBANY IN LARAMIE COUNTIES WITH ENHANCED LOWER LEVEL CONVERGENCE ALONG THE LARAMIE RANGE. THE KCYS RADAR LOOP ALSO SHOWS NUMEROUS BOUNDARIES IN THE VICINITY OF CYS...LIKELY PLAYING A ROLE IN CONVECTIVE EVOLUTION. CLOUDS CLEARED LATE THIS AM...HELPING PUSH SFC TEMPS INTO THE 55-65 DEGREE RANGE AMID DECENT LLVL MOISTURE WITH DEWPOINTS IN THE MID 40S F. THIS BENEATH STEEP MID LEVEL LAPSE RATES ON THE ORDER OF 8-9 DEG C/KM IS CONTRIBUTING TO SBCAPES ON THE ORDER OF 1500 J/KG PER THE 21Z SPC MESOANALYSIS. GFS AND NAM BUFKIT SOUNDINGS BOTH SHOW H5 FLOW AROUND 30 KTS...WHICH COMBINED WITH GOOD VEERING IN THE SFC-500 MILLIBAR LAYER IS CONTRIBUTING TO EFFECTIVE BULK SHEAR VALUES FAVORABLE FOR ROTATING UPDRAFTS (35-45 KTS). COULD SEE A HAIL THREAT EVOLVE WITH SOME CELLS...BUT DO NOT EXPECT TO SEE MORE THAN ONE OR TWO SEVERE STORMS. OPTED TO MAINTAIN SMALL HAIL AND GUSTY WIND WORDING IN THE OFFICIAL FORECAST. LATEST HRRR HAS CHANGED VERY LITTLE FROM THIS MORNING...AND APPEARS TO BE ACCURATELY SHOWING CONVECTIVE ELEMENTS BETWEEN LARAMIE AND CHEYENNE. FOR THAT REASON... WILL MAINTAIN LIKELY POPS FOR THOSE AREAS. CONVECTIVE COVERAGE WILL DWINDLE OVERNIGHT WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. QUASI-ZONAL FLOW ALOFT PERSISTS INTO SATURDAY. A SERIES OF MID LEVEL DISTURBANCES WILL TRAVERSE THE FLOW OVER THE CENTRAL ROCKIES...ONCE AGAIN PROMOTING AFTERNOON CONVECTION CHANCES. THE DAY 2 SPC OUTLOOK HAS SHIFTED THE MARGINAL RISK EAST OF OUR CWA...WHICH MAKES SENSE AS THE LATEST IN-HOUSE WRF PLACES THE BEST INSTABILITY AXIS EAST OF AN ALLIANCE TO SIDNEY LINE BETWEEN 18-20Z SAT. POTENTIAL FOR WIDESPREAD THUNDERSTORMS WILL DEPEND ON THE TIMING OF THE DRYLINE. GFS AND NAM BOTH PUSH THIS FEATURE EAST OF THE CWA BY EARLY TO MID AFTERNOON... BUT MODELS TEND TO MIX DRYLINES A BIT QUICKLY. LATER SHIFTS MAY NEED TO ADJUST POPS ACCORDINGLY IF IT APPEARS THE LOW-LEVEL CONVERGENCE ZONE WILL HANG ANY FURTHER WEST. A MUCH WARMER DAY APPEARS TO BE ON TAP TOMORROW FOR THE PLAINS WITH WESTERLY DOWNSLOPE FLOW...AND 700 MILLIBAR TEMPS AROUND 8-10 DEG C. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 354 PM MDT FRI MAY 1 2015 THIS PERIOD WILL BE DOMINATED BY GENERALLY CONSISTENT SOUTHWEST FLOW ACROSS THE INTERMOUNTAIN WEST AS YET ANOTHER LARGE SCALE TROUGH IS CARVED INTO THE WRN CONUS. MOISTURE ADVECTION ALONG WITH DIFFICULT TO TIME SHORTWAVES EMBEDDED WITHIN THIS FLOW WILL SET THE STAGE FOR A RELATIVELY UNSETTLED PERIOD. THIS BEGINS ON SUNDAY/MONDAY AS WEAK SFC BOUNDARY SETTLES SOUTH ACROSS THE PLAINS HANGING UP AROUND THE FRONT RANGE. MEANWHILE...RELATIVELY WEAK SHORTWAVE ENERGY WILL LIFT ACROSS THIS BOUNDARY AND WHEN COMBINED WITH WEAK INSTABILITY PROGS (SBCAPE 300- 500 J/KG) WILL PRODUCE AFTERNOON/EVENING CONVECTION BOTH DAYS. A STRONGER EJECTING TROUGH WILL MOVE THROUGH THE CWFA TUE/WED. BUT WITH MORE MOISTURE AND THICKER CLOUD CANOPY...INSTABILITIES ARE PROGD TO BE LESS. SOUTHWEST FLOW PERSISTS INTO THURSDAY WITH THE NEXT TROUGH SWINGING OUT OF THE DEEPENING WEST COAST TROUGH FOR FRIDAY OR FRIDAY NIGHT...DEPENDING ON THE MEDIUM RANGE GUIDANCE OF CHOICE. ISOLATED TO SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS ARE HARD TO ARGUE WITH REALLY ANY DAY NEXT WEEK. SO HAVE KEPT PRECIP CHANCES FAIRLY BROAD BRUSH BUT NOT WIDESPREAD NEXT WEEK. SUNDAY WILL BE THE WARMEST DAY OF THE WEEK WITH HIGHS REACHING THE 60S/70S. HIGHS WILL FALL BACK INTO THE 60S GENERALLY MON-FRI. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1102 PM MDT FRI MAY 1 2015 PATCHY FOG WITH IFR CONDITIONS NEAR THE SOUTHERN LARAMIE RANGE WILL PERSIST THE NEXT FEW HOURS BUT SHOULD DISSIPATE AS WEST WINDS ERODE THE FOG. FOG WILL BE POSSIBLE AT THE KCYS TAF SITE BUT OTHER TAF SITES WILL LIKELY NOT BE AFFECTED TONIGHT. OTHERWISE FOR TONIGHT THROUGH TOMORROW MORNING VFR FOR MOST OF THE FORECAST AREA. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP SATURDAY AFTERNOON. GUSTY WINDS AND SMALL HAIL WILL BE POSSIBLE WITH SOME STORMS. && .FIRE WEATHER... ISSUED AT 354 PM MDT FRI MAY 1 2015 FIRE WEATHER CONCERNS WILL BE ON THE LOW SIDE WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. WHILE ANY GIVEN STORM MAY PRODUCE GUSTY AND ERRATIC WINDS...NO DRY LIGHTNING IS EXPECTED. AFTERNOON RELATIVE HUMIDITY VALUES SHOULD REMAIN ABOVE 15 PERCENT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...RUBIN SHORT TERM...CLH LONG TERM...CAH AVIATION...SML FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
836 AM PDT Sat May 2 2015 .Synopsis... Warm temperatures with a slight chance of mountain thunderstorms continuing through early next week. Cooler and possibly more unsettled weather will set in late next week. && .Discussion... A cooler start to the day today, especially from Fairfield westward, where there has been cool Delta flow. Temperatures overall around 2 to 8 degrees cooler than this time on Friday. Highs today are on track to be in the upper 80s over most of the Valley, perhaps reaching around 90 for a few spots like Redding and Modesto. Vallejo/Benicia are currently overcast with marine stratus, and may struggle to reach 70 this afternoon. The mountains should be quite mild, maybe a couple of degrees cooler than on Friday. Temperatures on Sunday overall should drop a few degrees as atmospheric heights lower a bit more. Still, temperatures will remain well above normal levels. Forecast is on track, no changes made. EK .Extended Discussion (Wednesday through Saturday) Mid range models in fairly good agreement now in digging upper low pressure system over Pacific Northwest southward into Northern California on Wednesday. Even with the cooling expected on Wednesday...daytime highs are still forecast to come in just above normal for early May. Enough moisture and instability with this system to justify slight threat of mountain thunderstorms Wednesday but valley is likely to remain dry. Models dig the low farther south on Thursday and all linger the low over the western U.S but differ on the details as would be expected with a close low. Conditions become more unstable Thursday as cooler air aloft moves into the region and shower/thunderstorm threat will likely become more widespread. At this time...ECMWF and GFS have low/trough axis east of Norcal which would make the thunderstorm threat a mainly mountain only feature. GEM model holds low center over Norcal which would bring a shower/thunderstorm threat to all areas of Norcal. For now GEM is the outlying model and less favored. All models move the low little on Friday so expect little change Friday from Thursday in overall weather. All extended models shift the low into the Great Basin by next Saturday bringing much more stable conditions to the north state although RAP around moisture could still bring a threat of showers to the Sierra and northern mountains. Daytime high temperatures should be on a slight climbing trend by the end of next week. && .Aviation... Generally VFR conditions the next 24 hours across interior Northern California. A few thunderstorms may form along the Sierra this afternoon and early evening. Winds generally below 15 knots except southwest 15 to 20 knots gusting to 30 kt through the Delta and locally gusty in vicinity of Sierra thunderstorms. EK && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
345 AM PDT Sat May 2 2015 .Synopsis... Warm temperatures with a slight chance of mountain thunderstorms will continue through early next week. Cooler and possibly more unsettled weather will set in late next week. && .Discussion... Clear skies prevail across most of interior Northern California with dry westerly flow aloft. The marine layer has returned along the coast, although has deepened to only 1000 ft at Fort Ord. Even with a decent onshore push at this hour, we have only seen a modest amount of cooling across the interior. A bit of marine stratus has made it to the western Delta near Vallejo, but don`t expect it to push much farther inland by sunrise. Warm temperatures are expected to continue through the weekend, though the trend is a slow, gradually-cooling one. Highs today and Sunday across the Central Valley will be in the mid 80s to lower 90s, coolest near the Delta. Temperatures across the mountains should reach the 60s to 80s range. A few showers or thunderstorms will be possible again over the high Sierra and Lassen Park, but southwest flow aloft should quickly blow them east of the crest. Onshore flow should increase Monday into Tuesday as an upper trough moves through the Pacific Northwest. That should bring at least a bit more synoptic cooling and a stronger Delta Breeze. Temperatures are likely to remain above normal through the short term though. Dang .Extended Discussion (Wednesday through Saturday) Mid range models in fairly good agreement now in digging upper low pressure system over Pacific Northwest southward into Northern California on Wednesday. Even with the cooling expected on Wednesday...daytime highs are still forecast to come in just above normal for early May. Enough moisture and instability with this system to justify slight threat of mountain thunderstorms Wednesday but valley is likely to remain dry. Models dig the low farther south on Thursday and all linger the low over the western U.S but differ on the details as would be expected with a close low. Conditions become more unstable Thursday as cooler air aloft moves into the region and shower/thunderstorm threat will likely become more widespread. At this time...ECMWF and GFS have low/trough axis east of Norcal which would make the thunderstorm threat a mainly mountain only feature. GEM model holds low center over Norcal which would bring a shower/thunderstorm threat to all areas of Norcal. For now GEM is the outlying model and less favored. All models move the low little on Friday so expect little change Friday from Thursday in overall weather. All extended models shift the low into the Great Basin by next Saturday bringing much more stable conditions to the north state although RAP around moisture could still bring a threat of showers to the Sierra and northern mountains. Daytime high temperatures should be on a slight climbing trend by the end of next week. && .Aviation... Generally VFR conditions the next 24 hours across interior Northern California. A few thunderstorms may form along the Sierra this afternoon and early evening. Winds generally below 15 knots except southwest 15 to 20 knots through the delta and gusty in vicinity of thundestorms. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1100 AM EDT SAT MAY 2 2015 .SYNOPSIS... LOW PRESSURE OFF THE NORTH CAROLINA COAST WILL MOVE FARTHER OUT TO SEA TODAY. AN EXPANSIVE AREA OF HIGH PRESSURE WILL REMAIN IN CONTROL OF THE EASTERN THIRD OF THE COUNTRY THIS WEEKEND. THE CENTER OF THE HIGH WILL SHIFT OFFSHORE SUNDAY NIGHT AND MONDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST MONDAY NIGHT. THIS FRONT IS EXPECTED TO WEAKEN AND STALL OVER THE AREA TUESDAY INTO WEDNESDAY. HIGH PRESSURE BUILDS BACK INTO THE AREA LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MORNING CLOUDS HAVE PRETTY MUCH DISSIPATED ACROSS OUR CWA. MORNING SOUNDINGS DO SHOW CONVECTIVE TEMPS BEING REACHED. MODELING STILL SHOWING A LEE SIDE TROF DEVELOPING THIS AFTERNOON, BUT LAST FEW RAP AND HRRR NOT THAT ENTHUSED ABOUT SHOWERS. WE SCALED BACK COVERAGE, TIMING AND AMOUNTS. GIVEN YESTERDAY`S RESULTS WERE LESS THAN EXPECTED, IF MESOSCALE MODELING TREND CONTINUES, WE MAY DO FURTHER SCALING BACK WITH NEXT UPDATE. 12Z SOUNDINGS SHOWING MAX TEMPS IN THE 60S FOR TODAY. GIVEN CONTINUED AIR MASS MODIFICATION AND CONVECTIVE TEMPS IN THE 60S, WE SHOULD GET TO CURRENT HIGH TEMPS AND NO CHANGES WERE MADE. HIGH PRESSURE WILL SLOWLY BUILD INTO THE REGION FROM THE W AS LOW PRES OFF THE COAST MOVES AWAY FROM THE REGION. AS A RESULT, MAINLY DRY WX AND WARMING TEMPS ARE IN STORE TODAY. WITH LIGHT FLOW, TEMPS WILL BE COOLER ALG THE CST WHERE A SEABREEZE IS EXPECTED TO DEVELOP. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... THE SFC RIDGE WILL MOVE FURTHER INTO THE REGION TONIGHT AND EXPECT A GENLY CLEAR SKY AND NOT MUCH WIND. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE LARGE-SCALE PLAYERS NEXT WEEK INCLUDE PERSISTENT TROUGHING OVER THE WESTERN CONUS AND DOWNSTREAM RIDGING OVER MUCH OF THE EASTERN CONUS AND WESTERN ATLANTIC. THIS PATTERN WILL RESULT IN WARMER THAN NORMAL TEMPS AND FEW OPPORTUNITIES FOR PRECIPITATION FOR THE MID-ATLANTIC REGION FOR THE LONG-TERM PERIOD. MAX TEMPS GENERALLY RANGE FROM THE MID 70S TO LOWER 80S EACH DAY (EXCEPT COOLER ALONG THE COAST AND IN THE POCONOS). THE CENTER OF THE SURFACE HIGH PRESSURE AND H8 ANTICYCLONE WILL BE POSITIONED OVER THE SOUTHEAST STATES ON SUNDAY. THESE FEATURES WILL PROGRESS DOWNSTREAM TOWARD THE EAST COAST SUNDAY NIGHT AND THEN OVER THE WESTERN ATLANTIC ON MONDAY. SOUTHWESTERLY RETURN FLOW AROUND THE HIGH WILL DRAW EVEN WARMER AND SLIGHTLY MORE HUMID AIR UP THE EASTERN SEABOARD. A COLD FRONT IS EXPECTED TO DROP SOUTHWARD INTO THE REGION TUESDAY MORNING. THE COMBINATION OF UNIDIRECTIONAL W-SW FLOW ALOFT THAT BECOMES ORIENTED PARALLEL TO THE BOUNDARY AND DOWNSTREAM BLOCKING (FROM THE HIGH OVER THE WESTERN ATLANTIC AND CAROLINAS) WILL LIKELY CAUSE THE FRONT TO STALL OVER THE FORECAST AREA THRU WEDNESDAY. THE BOUNDARY WILL ALSO BECOME INCREASINGLY DIFFUSE DURING THIS TIME. THE BEST, IF NOT THE ONLY APPRECIABLE CHANCE FOR PRECIPITATION NEXT WEEK WILL BE TUESDAY-WEDNESDAY. WHILE FORCING FROM THIS DECAYING BOUNDARY ITSELF WILL BE WEAK, WE WILL HAVE TO WATCH FOR MID-LEVEL SHORTWAVE ENERGY THAT EJECTS OUT OF THE SOUTHWEST CONUS TROUGH TO RIDE ATOP THE DOWNSTREAM RIDGE AND EVENTUALLY MOVE INTO OUR AREA SOMETIME DURING THE TUESDAY AFTERNOON- WEDNESDAY MORNING PERIOD. THIS WOULD ENHANCE COVERAGE OF SHOWERS. HOWEVER, THE TIMING AND STRENGTH OF ANY SUCH IMPULSE IS STILL UNCERTAIN THIS FAR OUT, SO POPS WERE KEPT GENERALLY LOW. THE 00Z GUIDANCE PROGS THE GREATER INSTABILITY THAT MAY BE SUFFICIENT FOR CONVECTION TO BE CONFINED TO NEAR THE FRONT OWING TO MOISTURE POOLING ALONG THE BOUNDARY. KEPT CHANCES FOR THUNDERSTORMS LOW AREA WIDE DUE TO UNCERTAINTY IN THE LOCATION OF THE BOUNDARY. THE REMNANTS OF THE OLD FRONTAL BOUNDARY IS FORECAST TO BECOME WASHED OUT ACROSS THE AREA BY WEDNESDAY NIGHT. UPPER RIDGE BUILDING WILL OCCUR OVER THE MIDWEST AND MID ATLANTIC LATE IN THE WEEK. THIS ALLOWS THE WARMTH TO PERSIST ACROSS THE FORECAST AREA THRU THE END OF THE WEEK. MODELS ARE IN GOOD AGREEMENT WITH A CUTOFF LOW FORMING OFF THE SOUTHEAST COAST THURSDAY. WITH WEAK STEERING FLOW UNDERNEATH THE UPPER RIDGE, THE LOW IS NOT EXPECTED TO MAKE MUCH ADVANCEMENT TOWARD OUR AREA, RESULTING IN A DRY FORECAST FOR THURSDAY AND FRIDAY. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS ARE EXPECTED THRU THE TAF PD AS HIGH PRES BUILDS IN FROM THE W. THERE WILL BE SOME LINGERING SC AT TIMES THRU THE DAY BEFORE THE SKY BECOMES MAINLY CLR OVERNIGHT. WIND WILL SHIFT FROM NELY TO ELY AND EVENTUALLY S DURG THE DAY AND BECOME LIGHT OVERNIGHT. SPEEDS WILL REMAIN LESS THAN 10 KT. A SEA BREEZE FRONT IS EXPECTED TO WORK ITS WAY INLAND FROM THE CST DURG THE AFTN. OUTLOOK... SUNDAY AND MONDAY...VFR. LIGHT NW WINDS SUNDAY WILL BECOME SWLY AND INCREASE ON MONDAY. GUSTS TO 20 KT POSSIBLE MONDAY AFTERNOON. TUESDAY AND WEDNESDAY...PREDOMINATELY VFR. BRIEF/LOCAL RESTRICTIONS IN SCT SHOWERS AND ISO TSTMS AS A COLD FRONT DROPS SOUTHWARD AND THEN STALLS OVER THE AREA. BEST CHANCE FOR PRECIP WOULD BE TUESDAY AFTERNOON THRU WEDNESDAY MORNING. && .MARINE... WE MADE A COUPLE OF CHANGES TO THE WINDS FOR THIS AFTERNOON AND EVENING BASED ON LATEST 12Z NAM AND SOME OF THE LATEST HRRR AND RAP AS THEY HAVE A DECENT WIND SHIFT/ SEA AND BAY BREEZE FRONT PREDICTED TO DEVELOP. WE WILL EXTEND THE SCA FOR A FEW MORE HOURS AS OBSERVED SEAS ARE ABOUT A FOOT ABOVE WAVE WATCH GUIDANCE. ONCE THIS CURRENT SCA COMES DOWN, NO ADDITIONAL MARINE HEADLINES ARE EXPECTED IN THE NR OR SHORT TERM PDS. OUTLOOK... SUNDAY THROUGH WEDNESDAY...WINDS AND WAVES WILL PREDOMINATELY STAY BELOW SCA CRITERIA. S-SW FLOW WILL INCREASE TO 15-20 KT MONDAY AFTERNOON THRU WEDNESDAY BUT THE WARM AIR ATOP THE COLDER WATERS WILL NOT PROVIDE MUCH OPPORTUNITY FOR STRONGER WINDS ALOFT TO MIX DOWN TO THE SURFACE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ452>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ451. && $$ SYNOPSIS...KLEIN NEAR TERM...GIGI/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...KLEIN AVIATION...KLEIN/NIERENBERG MARINE...GIGI/KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
918 AM EDT SAT MAY 2 2015 .SYNOPSIS... LOW PRESSURE OFF THE NORTH CAROLINA COAST WILL MOVE FARTHER OUT TO SEA TODAY. AN EXPANSIVE AREA OF HIGH PRESSURE WILL REMAIN IN CONTROL OF THE EASTERN THIRD OF THE COUNTRY THIS WEEKEND. THE CENTER OF THE HIGH WILL SHIFT OFFSHORE SUNDAY NIGHT AND MONDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST MONDAY NIGHT. THIS FRONT IS EXPECTED TO WEAKEN AND STALL OVER THE AREA TUESDAY INTO WEDNESDAY. HIGH PRESSURE BUILDS BACK INTO THE AREA LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MORNING CLOUDS HAVE PRETTY MUCH DISSIPATED ACROSS OUR CWA. MORNING SOUNDINGS DO SHOW CONVECTIVE TEMPS BEING REACHED. MODELING STILL SHOWING A LEE SIDE TROF DEVELOPING THIS AFTERNOON, BUT LAST FEW RAP AND HRRR NOT THAT ENTHUSED ABOUT SHOWERS. WE SCALED BACK COVERAGE, TIMING AND AMOUNTS. GIVEN YESTERDAY`S RESULTS WERE LESS THAN EXPECTED, IF MESOSCALE MODELING TREND CONTINUES, WE MAY DO FURTHER SCALING BACK WITH NEXT UPDATE. 12Z SOUNDINGS SHOWING MAX TEMPS IN THE 60S FOR TODAY. GIVEN CONTINUED AIR MASS MODIFICATION AND CONVECTIVE TEMPS IN THE 60S, WE SHOULD GET TO CURRENT HIGH TEMPS AND NO CHANGES WERE MADE. HIGH PRESSURE WILL SLOWLY BUILD INTO THE REGION FROM THE W AS LOW PRES OFF THE COAST MOVES AWAY FROM THE REGION. AS A RESULT, MAINLY DRY WX AND WARMING TEMPS ARE IN STORE TODAY. WITH LIGHT FLOW, TEMPS WILL BE COOLER ALG THE CST WHERE A SEABREEZE IS EXPECTED TO DEVELOP. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... THE SFC RIDGE WILL MOVE FURTHER INTO THE REGION TONIGHT AND EXPECT A GENLY CLEAR SKY AND NOT MUCH WIND. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE LARGE-SCALE PLAYERS NEXT WEEK INCLUDE PERSISTENT TROUGHING OVER THE WESTERN CONUS AND DOWNSTREAM RIDGING OVER MUCH OF THE EASTERN CONUS AND WESTERN ATLANTIC. THIS PATTERN WILL RESULT IN WARMER THAN NORMAL TEMPS AND FEW OPPORTUNITIES FOR PRECIPITATION FOR THE MID-ATLANTIC REGION FOR THE LONG-TERM PERIOD. MAX TEMPS GENERALLY RANGE FROM THE MID 70S TO LOWER 80S EACH DAY (EXCEPT COOLER ALONG THE COAST AND IN THE POCONOS). THE CENTER OF THE SURFACE HIGH PRESSURE AND H8 ANTICYCLONE WILL BE POSITIONED OVER THE SOUTHEAST STATES ON SUNDAY. THESE FEATURES WILL PROGRESS DOWNSTREAM TOWARD THE EAST COAST SUNDAY NIGHT AND THEN OVER THE WESTERN ATLANTIC ON MONDAY. SOUTHWESTERLY RETURN FLOW AROUND THE HIGH WILL DRAW EVEN WARMER AND SLIGHTLY MORE HUMID AIR UP THE EASTERN SEABOARD. A COLD FRONT IS EXPECTED TO DROP SOUTHWARD INTO THE REGION TUESDAY MORNING. THE COMBINATION OF UNIDIRECTIONAL W-SW FLOW ALOFT THAT BECOMES ORIENTED PARALLEL TO THE BOUNDARY AND DOWNSTREAM BLOCKING (FROM THE HIGH OVER THE WESTERN ATLANTIC AND CAROLINAS) WILL LIKELY CAUSE THE FRONT TO STALL OVER THE FORECAST AREA THRU WEDNESDAY. THE BOUNDARY WILL ALSO BECOME INCREASINGLY DIFFUSE DURING THIS TIME. THE BEST, IF NOT THE ONLY APPRECIABLE CHANCE FOR PRECIPITATION NEXT WEEK WILL BE TUESDAY-WEDNESDAY. WHILE FORCING FROM THIS DECAYING BOUNDARY ITSELF WILL BE WEAK, WE WILL HAVE TO WATCH FOR MID-LEVEL SHORTWAVE ENERGY THAT EJECTS OUT OF THE SOUTHWEST CONUS TROUGH TO RIDE ATOP THE DOWNSTREAM RIDGE AND EVENTUALLY MOVE INTO OUR AREA SOMETIME DURING THE TUESDAY AFTERNOON- WEDNESDAY MORNING PERIOD. THIS WOULD ENHANCE COVERAGE OF SHOWERS. HOWEVER, THE TIMING AND STRENGTH OF ANY SUCH IMPULSE IS STILL UNCERTAIN THIS FAR OUT, SO POPS WERE KEPT GENERALLY LOW. THE 00Z GUIDANCE PROGS THE GREATER INSTABILITY THAT MAY BE SUFFICIENT FOR CONVECTION TO BE CONFINED TO NEAR THE FRONT OWING TO MOISTURE POOLING ALONG THE BOUNDARY. KEPT CHANCES FOR THUNDERSTORMS LOW AREA WIDE DUE TO UNCERTAINTY IN THE LOCATION OF THE BOUNDARY. THE REMNANTS OF THE OLD FRONTAL BOUNDARY IS FORECAST TO BECOME WASHED OUT ACROSS THE AREA BY WEDNESDAY NIGHT. UPPER RIDGE BUILDING WILL OCCUR OVER THE MIDWEST AND MID ATLANTIC LATE IN THE WEEK. THIS ALLOWS THE WARMTH TO PERSIST ACROSS THE FORECAST AREA THRU THE END OF THE WEEK. MODELS ARE IN GOOD AGREEMENT WITH A CUTOFF LOW FORMING OFF THE SOUTHEAST COAST THURSDAY. WITH WEAK STEERING FLOW UNDERNEATH THE UPPER RIDGE, THE LOW IS NOT EXPECTED TO MAKE MUCH ADVANCEMENT TOWARD OUR AREA, RESULTING IN A DRY FORECAST FOR THURSDAY AND FRIDAY. && .AVIATION /13Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS ARE EXPECTED THRU THE TAF PD AS HIGH PRES BUILDS IN FROM THE W. THERE WILL BE SOME LINGERING SC AT TIMES THRU THE DAY BEFORE THE SKY BECOMES MAINLY CLR OVERNIGHT. WIND WILL SHIFT FROM NELY TO ELY AND EVENTUALLY S DURG THE DAY AND BECOME LIGHT OVERNIGHT. SPEEDS WILL REMAIN LESS THAN 10 KT. A SEA BREEZE FRONT IS EXPECTED TO WORK ITS WAY INLAND FROM THE CST DURG THE AFTN. OUTLOOK... SUNDAY AND MONDAY...VFR. LIGHT NW WINDS SUNDAY WILL BECOME SWLY AND INCREASE ON MONDAY. GUSTS TO 20 KT POSSIBLE MONDAY AFTERNOON. TUESDAY AND WEDNESDAY...PREDOMINATELY VFR. BRIEF/LOCAL RESTRICTIONS IN SCT SHOWERS AND ISO TSTMS AS A COLD FRONT DROPS SOUTHWARD AND THEN STALLS OVER THE AREA. BEST CHANCE FOR PRECIP WOULD BE TUESDAY AFTERNOON THRU WEDNESDAY MORNING. && .MARINE... WE WILL EXTEND THE SCA FOR A FEW MORE HOURS AS OBSERVED SEAS ARE ABOUT A FOOT ABOVE WAVE WATCH GUIDANCE. ONCE THIS CURRENT SCA COMES DOWN, NO ADDITIONAL MARINE HEADLINES ARE EXPECTED IN THE NR OR SHORT TERM PDS. OUTLOOK... SUNDAY THROUGH WEDNESDAY...WINDS AND WAVES WILL PREDOMINATELY STAY BELOW SCA CRITERIA. S-SW FLOW WILL INCREASE TO 15-20 KT MONDAY AFTERNOON THRU WEDNESDAY BUT THE WARM AIR ATOP THE COLDER WATERS WILL NOT PROVIDE MUCH OPPORTUNITY FOR STRONGER WINDS ALOFT TO MIX DOWN TO THE SURFACE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ452>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ451. && $$ SYNOPSIS...KLEIN NEAR TERM...GIGI/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...KLEIN AVIATION...KLEIN/NIERENBERG MARINE...GIGI/KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS TOPEKA KS
911 AM CDT Sat May 2 2015 .UPDATE... Issued at 911 AM CDT SAT MAY 2 2015 Updated the forecast to keep a mention of scattered showers over eastern KS into the early afternoon. The RAP has analyzed a weak vort max drifting over the area which can be seen in the 500MB profiler data. Think the HRRR may have a reasonable grasp on the showers through the morning. Also there appears to be little or no instability. Mid level lapse rates are not that steep and models prog little change to them into the early afternoon. With there being little lightning activity now, do not think it will intensify over the next several hours so have removed the mention of thunder from the forecast. UPDATE Issued at 649 AM CDT SAT MAY 2 2015 More light showers are developing across central and south central KS this morning and have upped POPs for southern portions of forecast area this morning because of that. Precip falling from mid-level deck and considerable low-level dry air to overcome, so expect sprinkles to a few hundredths at most with this activity. Short range models weaken this area this morning as it moves east. Otherwise no changes to going forecast. && .SHORT TERM...(Today and Tonight) Issued at 351 AM CDT SAT MAY 2 2015 Showers/isolated thunderstorms across southeast Nebraska and far northeast KS are occurring in elevated warm advection zone near convergence at nose of low-level jet. This activity has been confined to far northeastern part of forecast area and should remain there this morning. Bigger question what else gets going in central/north central KS in the next few hours and that could move across a far greater portion of northeast KS this morning. Poorly defined shortwave trough seen best in RAP analysis and also somewhat apparent in water vapor loop moving toward north central KS at the current time. HRRR, RAP and 06Z NAM all have a larger area of precip developing in the next few hours apparently associated with this feature. If it develops as forecast, it will affect a wider part of northeast KS this morning than previously thought. Have expanded area of 20-30 percent POPs this morning due to trends in short range models, but difficult to go too high with virtually nothing showing up on radar over central KS at this time. Whatever precip develops should be moving out of far northeast KS early this afternoon and expect dry conditions for the rest of this afternoon through tonight as weak ridging aloft is over the area. Temps today will depend on cloud cover with far eastern KS most likely to see the most persistent clouds and temps only in the upper 70s while some clearing this afternoon in central KS should lead to lower 80s. .LONG TERM...(Sunday through Friday) Issued at 351 AM CDT SAT MAY 2 2015 By Sunday, models show a broad mid-level ridge stretched across the southern CONUS with surface low pressure extending from the High Plains into the Northern Plains. With this low pressure just west of the forecast area, a decent pressure gradient is expected to set up over the area, resulting in breezy southerly winds supporting good warm-air advection across the entire forecast area. With these conditions in place, have continued to trend on the warmer side of model guidance with highs in the low/mid 80s. Models continue to hold off on the front moving into north central Kansas until Sunday evening, so have a dry forecast for the daytime hours with chance to likely PoPs Sunday night through Monday as the cold front advances into the CWA and then stalls out over the area. By Monday the mid-level ridge will be focused across the southeastern U.S. and should start building northward Monday night into Tuesday, causing the stalled cold front to lift northward as a warm front. There are still some model discrepancies with how far north the warm front will lift (near the KS/NE border or into southern NE), but have lowered or even removed PoPs from far east central Kansas Monday night with likely PoPs still near the KS/NE border. The best chance for dry conditions looks to be on Tuesday with the front likely to the north, so have continued to drop PoPs to only slight chances or even dry for some locations. However, shower and thunderstorm chances return Tuesday night as a mid-level trough over the southwestern U.S. lifts northeastward toward the area, strengthening the surface low pressure system and pushing it into the High Plains. Models seem to be coming into slightly better agreement with the tracking of the mid-level trough and surface low, with the trough lifting into the Central Plains Wed/Wed night and into the Northern Plains by Thursday. At the surface, the surface low and associated cold front look to be stalled out along the High Plains Tuesday night through Wednesday before shifting a bit further east. With this steady southerly flow into the region, should see some modest moisture advection into the area by mid- week as we should be able to tap into moisture from the Gulf of Mexico. This moisture advection along with some mid-level forcing will bring increasing chances for scattered showers and thunderstorms Tuesday night through Wednesday night with diminishing chances for the remainder of the week as we lose the mid-level forcing. With low confidence in whether or not scattered precipitation will be lingering by the end of the week, have dropped PoPs to low-end chances for Thursday night and Friday. The persistent southerly flow and moisture advection also will lead to mild conditions with highs in the 70s and lows in the 50s/60s as well as humid conditions with dewpoints steadily in the 50s/60s. && .AVIATION...(For the 12Z TAFs through 12Z Sunday Morning) Issued at 649 AM CDT SAT MAY 2 2015 Considerable mid-level cloudiness expected for much of the day time hours. Light showers may affect MHK, TOP and FOE this morning but may be nothing more than sprinkles. Fewer clouds expected by late afternoon. VFR through the period. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Wolters SHORT TERM...GDP LONG TERM...Hennecke AVIATION...GDP
AREA FORECAST DISCUSSION
NWS TOPEKA KS
656 AM CDT Sat May 2 2015 ...Update to short term and aviation forecast discussion... .UPDATE... Issued at 649 AM CDT SAT MAY 2 2015 More light showers are developing across central and south central KS this morning and have upped POPs for southern portions of forecast area this morning because of that. Precip falling from mid-level deck and considerable low-level dry air to overcome, so expect sprinkles to a few hundredths at most with this activity. Short range models weaken this area this morning as it moves east. Otherwise no changes to going forecast. && .SHORT TERM...(Today and Tonight) Issued at 351 AM CDT SAT MAY 2 2015 Showers/isolated thunderstorms across southeast Nebraska and far northeast KS are occurring in elevated warm advection zone near convergence at nose of low-level jet. This activity has been confined to far northeastern part of forecast area and should remain there this morning. Bigger question what else gets going in central/north central KS in the next few hours and that could move across a far greater portion of northeast KS this morning. Poorly defined shortwave trough seen best in RAP analysis and also somewhat apparent in water vapor loop moving toward north central KS at the current time. HRRR, RAP and 06Z NAM all have a larger area of precip developing in the next few hours apparently associated with this feature. If it develops as forecast, it will affect a wider part of northeast KS this morning than previously thought. Have expanded area of 20-30 percent POPs this morning due to trends in short range models, but difficult to go too high with virtually nothing showing up on radar over central KS at this time. Whatever precip develops should be moving out of far northeast KS early this afternoon and expect dry conditions for the rest of this afternoon through tonight as weak ridging aloft is over the area. Temps today will depend on cloud cover with far eastern KS most likely to see the most persistent clouds and temps only in the upper 70s while some clearing this afternoon in central KS should lead to lower 80s. .LONG TERM...(Sunday through Friday) Issued at 351 AM CDT SAT MAY 2 2015 By Sunday, models show a broad mid-level ridge stretched across the southern conus with surface low pressure extending from the High Plains into the Northern Plains. With this low pressure just west of the forecast area, a decent pressure gradient is expected to set up over the area, resulting in breezy southerly winds supporting good warm-air advection across the entire forecast area. With these conditions in place, have continued to trend on the warmer side of model guidance with highs in the low/mid 80s. Models continue to hold off on the front moving into north central Kansas until Sunday evening, so have a dry forecast for the daytime hours with chance to likely PoPs Sunday night through Monday as the cold front advances into the CWA and then stalls out over the area. By Monday the mid-level ridge will be focused across the southeastern U.S. and should start building northward Monday night into Tuesday, causing the stalled cold front to lift northward as a warm front. There are still some model discrepancies with how far north the warm front will lift (near the KS/NE border or into southern NE), but have lowered or even removed PoPs from far east central Kansas Monday night with likely PoPs still near the KS/NE border. The best chance for dry conditions looks to be on Tuesday with the front likely to the north, so have continued to drop PoPs to only slight chances or even dry for some locations. However, shower and thunderstorm chances return Tuesday night as a mid-level trough over the southwestern U.S. lifts northeastward toward the area, strengthening the surface low pressure system and pushing it into the High Plains. Models seem to be coming into slightly better agreement with the tracking of the mid-level trough and surface low, with the trough lifting into the Central Plains Wed/Wed night and into the Northern Plains by Thursday. At the surface, the surface low and associated cold front look to be stalled out along the High Plains Tuesday night through Wednesday before shifting a bit further east. With this steady southerly flow into the region, should see some modest moisture advection into the area by mid- week as we should be able to tap into moisture from the Gulf of Mexico. This moisture advection along with some mid-level forcing will bring increasing chances for scattered showers and thunderstorms Tuesday night through Wednesday night with diminishing chances for the remainder of the week as we lose the mid-level forcing. With low confidence in whether or not scattered precipitation will be lingering by the end of the week, have dropped PoPs to low-end chances for Thursday night and Friday. The persistent southerly flow and moisture advection also will lead to mild conditions with highs in the 70s and lows in the 50s/60s as well as humid conditions with dewpoints steadily in the 50s/60s. && .AVIATION...(For the 12Z TAFs through 12Z Sunday Morning) Issued at 649 AM CDT SAT MAY 2 2015 Considerable mid-level cloudiness expected for much of the day time hours. Light showers may affect MHK, TOP and FOE this morning but may be nothing more than sprinkles. Fewer clouds expected by late afternoon. VFR through the period. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GDP SHORT TERM...GDP LONG TERM...Hennecke AVIATION...GDP
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
919 AM CDT Sat May 2 2015 .UPDATE... Issued at 907 AM CDT SAT MAY 2 2015 Raised PoPs over most of the CWA to account for ongoing convection over the northwest third of the forecast area as well as the approaching activity now over central KS. The northwest MO activity is associated with moderately strong isentropic ascent on the 300K and 305K surfaces as well as support from a shortwave trough moving east across NE. The KS activity is associated with a weak mid-level vorticity trough and vorticity max. The 12z NAM picks up on the KS vorticity max and even strengthens it as it moves into northwest MO. Not quite buying the strengthening process nor the placement but do expect the feature to persist as it moves east into the CWA. The HRRR model trend maintains a steady flow of scattered showers being generated over southeast NE and moving into northwest MO while the initial activity weakens as it moves into northeast MO. The HRRR also holds onto the KS activity as it crosses into west central MO by 18z as well as continuing east into the central portion of the forecast area. What this all means is a need to increase PoPs and clouds across the CWA and a need to lower temperatures across the northern half of the CWA where PoPs are highest. Will monitor cloud/precipitation trends as there is a good chance we`ll need to lower temperatures further over the west central CWA. One last item is we`ve stripped away thunder from the forecast as the instability is puny and not expected to increase. There may be a stray cg strike in the far northwest near the southern edge of the stronger isentropic ascent and where lightning is occurring over southwest IA. && .DISCUSSION... Issued at 351 AM CDT SAT MAY 2 2015 Today/Tonight: Several subtle upper disturbances will move through the region, aiding in the development of scattered convection. The most probable locations to receive light measurable precipitation will be along and north of the Interstate 70 corridor. The most active period should coincide with the approach of these impulses, with this morning into the early afternoon one round, and another possible overnight. Modest instability will gradually increase from west to east during the day, and therefore a few scattered thunderstorms will be possible this morning into the evening. Temperatures should warm well into the 70s during the afternoon, even with broken cloud cover. Overnight temperatures will remain in the lower 60s to upper 50s in part to increased moisture advection and cloud cover. Sunday/Monday: A large upper trough skirting the US/Canada border will send a cold front approaching the area by Sunday night. This will be the primary focus for the most spatially concentrated area for convection during this period. The front is expected to settle near northwest Missouri on Monday before stalling, and with strong daytime heating, convection is expected to develop over NW MO. Deep layer shear is expected to be rather weak, unless a subtle upper disturbance not yet resolvable can enhance speeds, although moderate instability around MUCAPE 1500 J/kg will develop ahead of the boundary. While severe weather is not likely, a few stronger storms may evolve during the afternoon and evening hours. Tuesday through Saturday: An active pattern looks to evolve across much of the region, albeit severe weather probabilities still appear low/uncertain at this time. A negatively-tilted shortwave trough is projected to lift into the Plains Tuesday into Wednesday. In its wake, continued southwesterly flow will establish over the region, with several embedded upper disturbances expected to move through. While specific details are not resolvable in this period for this particular pattern, it is reasonable to believe several episodes of convection will be possible for portions of the area. Questions regarding an initial meridional wind field and the degree of destabilization limits confidence/signal for severe weather. As for temperatures, above normal readings are expected to continue, with highs in the 70s and 80s. && .AVIATION...(For the 12Z TAFS through 12Z Sunday Morning) Issued at 548 AM CDT SAT MAY 2 2015 VFR anticipated through the period. Scattered convection near terminals should result in minimal impacts. Scattered precipitation should clear area by mid-afternoon. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...MJ DISCUSSION...Blair AVIATION...Blair
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
902 AM MDT SAT MAY 2 2015 .UPDATE... FORECAST WAS IN GOOD SHAPE THIS MORNING. ONLY CHANGES WERE TO INCREASE WIND SPEEDS OVER SOME AREAS DUE TO WINDS ALREADY KICKING UP IN KLVM...KBIL AND KBHK...AND DUE TO THE STRONG INVERTED-V NATURE OF RAP SOUNDINGS AND GOOD W FLOW THROUGH THE COLUMN. ALSO ADJUSTED MORNING SKY COVER WITH SATELLITE IMAGERY SHOWING AREAS OF HIGH CLOUDINESS ACROSS THE REGION. COLD FRONT WAS ENTERING N MT PER 14Z SURFACE OBSERVATIONS. FRONT WAS NOT OVERLY STRONG WITH ONLY A 10 DEGREE TEMPERATURE DIFFERENCE ACROSS THE BOUNDARY AND NO REAL DEWPOINT DIFFERENCE. MODELS HAD THE FRONT MOVING INTO THE NORTHERN FORECAST AREA BY 00Z...THEN SINKING S THROUGH THE REMAINDER OF THE AREA BY 06Z WITH SURFACE WINDS BECOMING NE. MODELS WERE IN GOOD AGREEMENT IN KEEPING THE PRECIPITATION CHANCES FOCUSED OVER THE S MOUNTAINS. OTHERWISE...LIFT WAS LIMITED WITH LITTLE JET DIVERGENCE AND ONLY WEAK FRONTOGENESIS. NOTED THE HRRR TRIED TO DEVELOP SOME CONVECTION NEAR KMLS...BUT WITH THE AIRMASS BEING SO DRY...THIS WILL NOT BE A CONCERN. TEMPERATURES AND RELATIVE HUMIDITIES WERE IN GOOD SHAPE TODAY. CONVECTION SHOULD PERSIST OVER THE MOUNTAINS INTO THIS EVENING THEN SHIFT E OVERNIGHT. ARTHUR && .SHORT TERM...VALID FOR TDY AND SUN... FAIRLY UNEVENTFULL WEEKEND IN STORE WITH THE EXCEPTION OF A COLD FRONT WHICH WILL MOVE ACROSS THE FORECAST AREA TODAY. A FAST AND MAINLY WESTERLY FLOW ALOFT WILL CONTINUE TODAY THROUGH MOST OF SUNDAY. A COLD FRONT WILL DROP SOUTH ACROSS THE AREA LATE THIS AFTERNOON BRINGING A WIND SHIFT TO THE NORTHWEST THEN NORTHEAST TONIGHT INTO SUNDAY. MODELS SHOW VERY LITTLE MOISTURE ASSOCIATED WITH THE FRONT BUT WE WILL CONTINUE WITH A SLIGHT SHOWER/THUNDERSTORM CHANCE...MAINLY OVER AND NEAR THE MOUNTAINS THIS AFTERNOON THROUGH THIS EVENING. TEMPERATURES TODAY WILL AGAIN BE ABOVE NORMAL WITH MOST AREAS WARMING INTO THE MIDDLE TO UPPER 70S WITH POSSIBLY AN 80 DEGREE READING FOR A FEW AREAS. STRONGER JET DYNAMICS STAY ALONG THE CANADIAN BORDER DURING THE DAY SUNDAY. HOWEVER...A SMALL DISTURBANCE WILL MOVE NORTH OUT OF COLORADO AND WYOMING DURING THE AFTERNOON AND EVENING. THIS DISTURBANCE WILL MAINLY STAY TO OUR SOUTH ACROSS WYOMING BUT THE NORTHERN EDGE MAY BRUSH OUR FAR SOUTHERN AREAS ALONG THE MONTANA/WYOMING BORDER SO WILL MAINTAIN A SLIGHT SHOWER CHANCE FOR THOSE AREAS. TEMPERATURES SUNDAY WILL BE COOLER AND CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH READINGS IN THE 60S. HOOLEY .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... MODELS HAVE CONTINUED TO SHOW BETTER AGREEMENT WITH THE LATEST RUNS. THEY CONTINUE TO CONVERGE ON THE GENERAL SOLUTION THE GFS HAS BEEN PRESENTING OVER THE PAST SEVERAL RUNS OF A PACIFIC LOW MOVING ON SHORE AND INTO THE NORTHERN GREAT BASIN. THE SPECIFICS REMAIN UNCERTAIN. THERE REMAINS A LARGE SPREAD IN THE GFS ENSEMBLE WELL AS BETWEEN THE GFS...EC...AND GEM. WITH THE INCREASING CONFIDENCE...HAVE INCREASED POPS SLIGHTLY. ALSO THERE IS SOME CAPE DURING THE AFTERNOON ON WEDNESDAY...SO HAVE ADDED SOME THUNDERSTORMS WEDNESDAY. THE BEGINNING OF THE WEEK WILL SEE WARM TEMPERATURES...WITH THE AREA IN WESTERLY FLOW. WITH SOME LIFT AS A WEAK WAVE MOVES THROUGH THE FLOW. THE MOUNTAINS WILL HAVE A SLIGHT CHANCE FOR RAIN...AN ISOLATED THUNDERSTORM COULD MOVE OFF THE TERRAIN INTO THE WESTERN PLAINS. WITH INCREASED CLOUD COVER AND INCREASED RAIN CHANCES FOR THE SECOND HALF OF THE WEEK...TEMPERATURES WILL BE BACK NEAR NORMAL IN THE MID 60S. REIMER && .AVIATION... VFR EXPECTED OVER THE NEXT 24 HOURS. NO AVIATION HAZARDS EXPECTED. REIMER/FRIEDERS && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 078 045/066 044/077 048/078 047/063 043/053 038/060 0/B 11/B 11/B 22/T 43/T 44/W 33/W LVM 074 036/066 038/075 043/075 041/060 038/050 033/058 1/N 11/B 12/T 23/T 44/T 44/W 33/W HDN 081 042/069 042/080 045/079 047/065 041/053 035/062 0/B 11/B 21/B 12/T 43/T 44/W 32/W MLS 080 045/067 043/075 049/078 050/066 042/054 037/061 1/B 11/B 12/W 12/T 43/T 33/W 32/W 4BQ 080 044/067 044/073 047/076 049/064 043/054 035/061 0/B 11/B 32/T 12/T 44/T 43/W 22/W BHK 079 040/064 038/071 044/072 049/061 041/055 033/058 0/B 21/B 12/T 11/N 44/T 43/W 33/W SHR 077 043/065 043/071 043/073 045/061 040/053 033/057 0/B 12/W 22/T 23/T 44/T 44/W 33/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1032 AM EDT SAT MAY 2 2015 .SYNOPSIS... HIGH PRESSURE WILL PROVIDE AN IDEAL SPRING WEEKEND WITH PLENTY OF SUNSHINE AND WARM TEMPERATURES AWAY FROM THE IMMEDIATE LAKESHORES. A COLD FRONT WILL CROSS THE AREA LATE MONDAY THROUGH TUESDAY AND BRING THE NEXT CHANCE OF RAIN AND POSSIBLY A FEW THUNDERSTORMS. TEMPERATURES WILL ONLY COOL FOR ONE DAY BEHIND THE COLD FRONT WITH PLENTY OF WARMTH RETURNING FOR THE SECOND HALF OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... IR SATELLITE IMAGERY SHOWS PATCHY HIGH CLOUDS EXTENDING FROM OHIO INTO THE LOWER LAKES. THESE WILL CONTINUE TO MOVE ACROSS THE REGION TODAY BUT WILL NOT BE THICK ENOUGH TO HAVE MUCH OF AN IMPACT ON TEMPERATURES. ONLY VERY MINOR CHANGES FOR THE FORECAST UPDATE. WILL BLEND IN THE HRRR TO FINE TUNE LAKE-BREEZES AND UPDATE SKY COVER BASED ON LATEST SATELLITE TRENDS. HIGH PRESSURE SURFACE AND ALOFT WILL BUILD INTO THE OHIO VALLEY AND GREAT LAKES TODAY AND PROVIDE A CONTINUATION OF THE VERY PLEASANT SPRING WEATHER. 850MB TEMPS OF AROUND +7C WILL SUPPORT HIGHS IN THE LOWER 70S AT LOWER ELEVATIONS INLAND FROM THE LAKES... WITH UPPER 60S ON THE HILLS. SOUTHWEST GRADIENT ONSHORE FLOW WILL KEEP AREAS EAST AND NORTHEAST OF LAKES ERIE AND ONTARIO COOLER... INCLUDING THE BUFFALO AND WATERTOWN AREAS. STRONG DIFFERENTIAL HEATING SHOULD ALLOW SOME SEMBLANCE OF A LAKE BREEZE TO DEVELOP ALONG THE SOUTH SHORE OF LAKE ONTARIO AND TURN THE SURFACE WINDS MORE NORTHWEST DURING THE AFTERNOON...COOLING THAT LAKESHORE AS WELL. TONIGHT HIGH PRESSURE WILL REMAIN IN PLACE FROM THE OHIO VALLEY TO THE MID ATLANTIC. A WEAK MID LEVEL SHORTWAVE WILL ROUND THE TOP OF THE RIDGE AND CROSS SOUTHERN ONTARIO AND NORTHERN NY. THIS MAY BRING A FEW PATCHY CLOUDS TO THE NORTH COUNTRY...BUT OTHERWISE MAINLY CLEAR SKIES WILL CONTINUE FOR THE REST OF THE AREA. EXPECT LOWS IN THE MID TO UPPER 40S ON THE LAKE PLAINS...WITH LOWER 40S AND EVEN UPPER 30S IN THE COOLER SOUTHERN TIER VALLEYS AND TUG HILL REGION. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... NO CHANGES MADE. SHORTWAVE UPPER-LEVEL RIDGING BUILDS ACROSS THE FORECAST AREA ON SUNDAY...WITH A SURFACE HIGH SLIDING OFF THE MID ATLANTIC COAST. THE RISING HEIGHTS ACROSS WESTERN NEW YORK WILL PUSH 850 MB TEMPERATURES TO AROUND +8C BY SUNDAY AFTERNOON. WITH THE SURFACE HIGH LOCATED SE OF THE AREA...WINDS WILL TURN TOWARD TO THE SOUTHWEST. SOUTHWEST WINDS WILL FAVOR DOWNSLOPE FLOW IN THE GENESEE VALLEY AND NORTHEAST OF THE TUG HILL REGION. THIS WILL ALLOW FOR THE WARMEST TEMPERATURES READING PUSHING CLOSE TO 80 IN THESE REGIONS. ELSEWHERE...MID 70S WILL BE COMMON. UNFORTUNATELY FOR THE BUFFALO AND WATERTOWN METRO AREAS...A SOUTHWEST FLOW MEANS LAKE BREEZES WILL KEEP THE IMMEDIATE SHORELINE THE COOLEST / WITH TEMPS IN THE 50S/ WITH STEADILY INCREASING TEMPERATURES INLAND. SKIES SHOULD BE MAINLY CLEAR...WITH THE EXCEPTION OF SOME AFTERNOON CUMULUS DEVELOPING OVER THE ALLEGHENY PLATEAU. THESE CU COULD BECOME DEVELOPED ENOUGH TO SUPPORT A LIGHT SPRINKLE OR SHOWER...BUT GIVEN RISING HEIGHTS AND DRY LOW-LEVELS WILL ONLY GIVE THIS A SLIGHT CHANCE. SUNDAY NIGHT WILL BE VERY MILD WITH LIGHT SOUTHERLY WINDS AND MOONLIT SKIES. TEMPERATURES WILL REMAIN IN THE 50S FOR MOST LOCATIONS. THE EXCEPTION WILL BE ANY INTERIOR VALLEYS WHERE THE WINDS CAN GO CALM...BUT EVEN THEN TEMPERATURES WILL ONLY LIKELY DIP INTO THE 40S. ON MONDAY...AN APPROACHING SHORTWAVE OVER THE UPPER GREAT LAKES...WILL INCREASE THE SOUTHWESTERLY FLOW ACROSS WESTERN AND CENTRAL NEW YORK. WINDS WILL PICK UP AND BECOME GUSTY BY MONDAY AFTERNOON AHEAD OF THE ASSOCIATED COLD FRONT MOVING IN FROM THE WEST. WINDS WILL LIKELY BE STRONGEST ACROSS THE NIAGARA FRONTIER AND INTO THE SAINT LAWRENCE RIVER VALLEY...WITH WIND GUSTS 30 TO 35 MPH LIKELY BY MONDAY AFTERNOON. THE COMBINATION OF THE THERMAL RIDGE FINALLY CROSSING THE FORECAST AREA AHEAD OF THE FRONT AND THE INCREASE SOUTHWESTERLY WINDS WILL PROMOTE AND EVEN WARMER DAY THAN SUNDAY. LOCATION ALONG THE GENESEE VALLEY SHOULD EASILY PUSH INTO THE LOWER 80S WITH THE STRONG DOWNSLOPE FLOW. ELSEWHERE MOST LOCATIONS WILL EASILY IN THE MID 70S. THE SAME EXCEPTIONS APPLY FOR BUFFALO AND WATERTOWN AS ON SUNDAY...WHERE THE SOUTHWEST FLOW OFF THE LAKE WILL KEEP THE METRO AREAS MUCH COOLER. BY LATE MONDAY...SCATTERED RAIN SHOWERS AND THUNDERSTORMS WILL APPROACH THE AREA FROM THE WEST ALONG THE COLD FRONT. WITH THE SHORTWAVE TROUGH PASSING WELL TO THE NORTH...DONT EXPECT A STRONG PUSH OF PRECIPITATION WITH THE FRONT...BUT WILL BE ENOUGH TO HELP FOCUS SCATTERED SHOWERS AND THUNDERSTORMS. THE OTHER CONSEQUENCE OF THE SHORTWAVE DEPARTING TO THE NORTH IS THAT THE FRONT BOUNDARY WILL SAG ACROSS THE FORECAST AREA MONDAY NIGHT AND BECOME STALLED ALMOST WEST-EAST ACROSS NEW YORK STATE. WITH FRONTOGENSIS AND SOME LIGHT ISENTROPIC ASCENT OVER THE BOUNDARY BEING THE ONLY FORCING MECHANISM...EXPECT FAIRLY SCATTERED / DISORGANIZED SHOWERS AND POSSIBLY SOME RUMBLES OF THUNDER TO LINGER MONDAY NIGHT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE AFOREMENTIONED BAROCLINIC ZONE WILL BE STALLED ACROSS OR JUST SOUTH OF THE FORECAST AREA BY TUESDAY MORNING. THIS BOUNDARY WILL SLOWLY CONTINUE TO SHIFT SOUTH THROUGH THE DAY. LIGHT NORTHERLY FLOW IN PLACE ON BOTH THE 00Z GFS AND 00Z ECMWF DEPICTING THE COLD FRONT TO REMAIN SOUTH OF THE REGION BY MIDDAY. HIGHS WILL REMAIN SLIGHTLY BELOW NORMAL WITH AFTERNOON TEMPERATURES ONLY IN THE LOWER 60S. SKIES WILL CLEAR OUT TUESDAY NIGHT. THE REMAINDER OF THE WORK WEEK WILL LIKELY REMAIN DRY AS ANOTHER RIDGE OF HIGH PRESSURE FROM SOUTHERN CANADA BECOMES ESTABLISHED OVER THE MIDWEST AND EASTERN GREAT LAKES REGION. TEMPERATURES WILL GRADUALLY WARM THROUGH THE PERIOD WITH HIGHS WEDNESDAY AROUND 70...INCREASING TO THE MID 70S TO LOWER 80S BY THE END OF THE WEEK. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... VFR WILL PREVAIL FOR THE 15Z TAF CYCLE. AN AREA OF THIN CIRRUS LEVEL CLOUDINESS WILL CROSS THE REGION FROM WEST TO EAST TODAY...AND SOME SCT DIURNAL CUMULUS MAY DEVELOP BY AFTERNOON ACROSS THE HIGHER TERRAIN WELL INLAND FROM THE LAKES...NEITHER OF WHICH WILL HAVE ANY IMPACT ON AVIATION. A FEW MORE MID LEVEL CLOUDS BEGIN TO INCREASE LATER TONIGHT. OUTLOOK... SUNDAY AND MONDAY...VFR. MONDAY NIGHT AND TUESDAY...A CHANCE OF SHOWERS AND THUNDERSTORMS AND LOCAL MVFR. WOODENEST...VFR. && .MARINE... HIGH PRESSURE WILL SLOWLY CROSS THE LOWER LAKES AND OHIO VALLEY THIS WEEKEND AND PROVIDE RELATIVELY LIGHT WINDS AND WAVE ACTION. SOUTHWEST WINDS WILL INCREASE SOME ON MONDAY AHEAD OF A COLD FRONT...ALTHOUGH THE COLD LAKE WATERS WILL STABILIZE THE BOUNDARY LAYER OVER THE LAKES AND KEEP WINDS LIGHTER IN THE MARINE ENVIRONMENT THAN OVER THE SURROUNDING LAND. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...HITCHCOCK NEAR TERM...APFFEL/HITCHCOCK SHORT TERM...CHURCH/HIBBERT LONG TERM...CHURCH AVIATION...APFFEL/HITCHCOCK MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
946 AM EDT SAT MAY 2 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND INTO MUCH OF THE EARLY WEEK. OUR NEXT BEST CHANCE OF PRECIPITATION WILL COME DURING THE MIDDLE OF NEXT WEEK WHEN A BACKDOOR COLD FRONT APPROACHES OUR AREA. && .NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM EDT SATURDAY... OVERALL A NICE DAY TO START OFF THE WEEKEND. THE DENSE FOG ADVISORY EXPIRED AT 9AM. THERE ARE STILL SOME ISOLATED POCKETS OF RIVER VALLEY FOG ACROSS THE MOUNTAIN EMPIRE...HOWEVER THAT SHOULD BURN OFF WITHIN THE NEXT HOUR OR SO. MOST OF THE REGION CAN EXPECT A DRY AND PARTLY SUNNY DAY...ALTHOUGH THERE IS THE SLIGHT CHANCE FOR AN ISOLATED SHOWER FOR A BRIEF WINDOW THIS AFTERNOON EAST OF THE BLUE RIDGE. HRRR CONTINUES TO SHOW WEAK INSTABILITY OF 100-300 MU CAPE EARLY THIS AFTERNOON AND WANTS TO POP UP A FEW SHOWERS...THEREFORE ADDED SLIGHT CHANCE POPS OUT EAST. AS OF 730 AM EDT SATURDAY... DENSE FOG ADVISORY FOR A FEW COUNTIES IN THE NORTH EXPIRES AT 13Z. SURFACE AND UPPER LOW WILL CONTINUE TO MOVE FURTHER OUT INTO THE ATLANTIC OCEAN TODAY WITH HIGH PRESSURE AND DRIER AIR OVER THE OHIO VALLEY BUILDING EASTWARD. TODAY WILL BE PARTLY TO MOSTLY SUNNY AND MILDER WITH HIGHS ACROSS THE MOUNTAINS RANGING FROM THE MID 60S TO NEAR 70 DEGREES...WITH LOW TO MID 70S ACROSS THE PIEDMONT. CONTINUED DRY AND TRANQUIL OVERNIGHT WITH LOWS NEAR SEASONAL NORMALS IN THE 40S. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 PM EDT FRIDAY... WEAK HIGH PRESSURE WILL SLIDE ACROSS THE REGION SUNDAY. AS THIS HIGH MOVES TO THE COAST...LIGHT SOUTHERLY FLOW WILL BRING WARM MOIST AIR INTO THE REGION. WITH SOME WEAKNESS ALOFT FROM AN UPPER LEVEL TROUGH...ISOLATED SHOWERS ARE POSSIBLE OVER THE NORTH CAROLINA HIGH COUNTRY LATE SUNDAY AFTERNOON. ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE MONDAY AFTERNOON AS A COOL POOL ALOFT DRIFTS OVER THE REGION. TEMPERATURES WILL RUN WARMER THAN NORMAL SUNDAY AND MONDAY WITH AREAS SEEING SHOWERS PEAKING IN THE UPPER 60S AND LOCATIONS REMAIN DRY WARMING INTO THE 70S. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 125 PM EDT FRIDAY... LONG WAVE PATTERN ADVERTISED BY MODELS SHOWED TROFING IN THE WESTERN UNITED STATES AND A BROAD SOUTHEAST U.S. RIDGE. A SURFACE COLD FRONT THE THE NORTHERN STREAM WILL BE OVER THE GREAT LAKES ON MONDAY AND WILL PUSH SOUTH AS A BACKDOOR FRONT OVER THE MID ATLANTIC REGION TUESDAY AND WEDNESDAY. QUESTIONABLE HOW FAR SOUTH THIS BOUNDARY GETS HEADING INTO A LARGE RIDGE OVER THE SOUTHEAST. BEST PROBABILITY OF PRECIPITATION WILL BE IN THE VICINITY OF THIS BOUNDARY. OTHERWISE THE CHANCE WILL BE LIMITED TO AIRMASS TYPE THUNDERSTORMS...MAINLY IN THE MOUNTAINS EACH AFTERNOON AND EVENING. MAXIMUM/MINIMUM TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE NORMAL TUESDAY THROUGH FRIDAY. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... AS OF 735 AM EDT SATURDAY... PATCHY FOG POSSIBLE FOR AN HOUR OR TWO THIS MORNING BUT AFTER 13Z EXPECT VFR CONDITIONS AREA WIDE TODAY. WINDS LIGHT AND MOSTLY NW TODAY BECOMING CALM OR LIGHT VARIABLE THIS EVENING AND OVERNIGHT. NOTE...THE VISIBILITY SENSOR AT THE ASOS AT KBLF CONTINUES TO MALFUNCTION. WILL CONTINUE WITH AMD NOT SKED APPENDED TO ITS TAF. EXTENDED AVIATION DISCUSSION... OTHER THAN SOME PATCHY LATE NIGHT/EARLY MORNING RIVER VALLEY FOG IN THE TYPICAL LOCATIONS...VFR CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. SCATTERED AFTERNOON SHOWERS COULD AFFECT THE MOUNTAINS TUE...BUT MORE LIKELY WED-THU AS A BACK DOOR FRONT DRIFTS TOWARD THE REGION. HIGH PRESSURE ALOFT WILL NOT PROVIDE MUCH IN THE WAY OF ANY SYNOPTIC-SCALE FORCING THROUGH THE PERIOD THOUGH. && .EQUIPMENT... AS OF 907 PM EDT FRIDAY... THE VISIBILITY SENSOR AT THE BLUEFIELD...KBLF...ASOS MAY ALTERNATE BETWEEN AVAILABLE AND UNAVAILABLE UNTIL SUCH TIME APPROPRIATE CORRECTIVE MEASURES CAN BE COMPLETED. THE NOAA WEATHER RADIO AT ROANOKE VIRGINIA...WXL60...WHICH BROADCASTS AT A FREQUENCY OF 162.475 MHZ...IS BACK ON THE AIR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...CF/PC SHORT TERM...RCS LONG TERM...AMS AVIATION...DS/PC EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
348 PM EDT SAT MAY 2 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN TO OUR SOUTH THROUGH MONDAY, KEEPING FAIR WEATHER ACROSS THE AREA. A COLD FRONT IS FORECAST TO MOVE ACROSS THE AREA TUESDAY, THEN STALL SOUTH OF THE AREA THROUGH THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... A COMBINATION OF THE GFS AND WRF-NMM LOOKED BEST OFF THE 500MB INITIALIZATION WITH A SLIGHT NOD TO THE WRF-NMMB AT BOTH 850MB AND 925MB WHERE THE GFS SHOWED SOME 1C COLD BIASES. MODERATING TREND THROUGH THE SHORT TERM WILL CONTINUE WITH LITTLE IF ANY PCPN AND NO PCPN EXPECTED AFTER EARLY THIS EVENING. THE HRRR HAD A GOOD HANDLE ON LOCATIONS OF BULKIER CU AND ADJUSTMENTS TO ISOLATED SHOWERS (MORE LIKELY JUST SPRINKLES OR A FEW BIG DROPS HITTING THE WINDSHIELD) WERE BASED ON ITS LATEST OUTPUT. FORECAST SOUNDINGS STILL ARE CAPPED AND WITH THE SHORT WAVE MOVING OFFSHORE SHOULD ONLY BECOME MORE SO AS THE AFTN AND EARLY EVE PROGRESS, SO NO THUNDER. BASED ON UPWIND SATL INFO, DOESNT LOOK LIKE CLOUDS ARE GOING TO GET TRAPPED UNDER THE INVERSION, SO MOST SHOULD BE GONE BY EVENING`S END. WINDS WILL BE LIGHT, IF NOT CALM, IN MOST AREAS. WE RADIATED MIN TEMPS DOWN TOWARD THE LOWER STAT GUIDANCE DATASETS. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... INCREASED RIDGING AND FARTHER OFFSHORE MOVEMENT OF THE 500MB TROF AND SFC LOW WILL TRANSLATE INTO A WARMER DAY ON SUNDAY WITH LESS CUMULUS CLOUDS AROUND AND NO CHANCE FOR PCPN. 18C AIR AT BOTH 925MB AND 850MB OVER THE UPPER PLAINS WILL START MAKING A TURN TOWARD OUR CWA, BUT NOT ARRIVE IN TIME FOR SUNDAY. NEVERTHELESS, THERE WILL BE A SEVERAL DEG C UPTICK IN TEMPS AT BOTH THOSE LEVELS SUNDAY. LIKE TODAY, THE WARMER PART OF OUR AIR MASS WILL BE OVER THE NWRN PART OF OUR CWA VS SOUTHEAST. THUS MAX TEMPS (AWAY FROM THE IMMEDIATE SHORE AND HIGHER TERRAIN) ARE PREDICTED TO BE QUITE UNIFORM. THIS IS IN LINE WITH FCST CONTINUITY AND THE HIGHER MOS DATASETS. A SEA BREEZE FRONT SHOULD FORM AGAIN, LIKELY NOT AS VIGOROUS AS TODAY`S. NONETHELESS SOME COOLING WILL OCCUR AT OR CLOSER TO THE COAST AS THE AFTERNOON PROGRESSES. WATER TEMPS ARE STILL QUITE CHILLY. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THE HIGH PRESSURE TO OUR SOUTH BUILDS SLIGHTLY FURTHER OFFSHORE SUNDAY NIGHT, BUT MOSTLY REMAINS IN PLACE THROUGH MONDAY. THE HIGH WILL BEGIN GETTING SQUEEZED FURTHER OFFSHORE AND AWAY FROM THE AREA MONDAY NIGHT. HOWEVER, OUR AREA ON THE NORTHERN FRINGE OF THE HIGH THROUGH MONDAY NIGHT, WHICH WILL KEEP RATHER TRANQUIL WEATHER ACROSS THE AREA THROUGH MONDAY NIGHT. A COLD FRONT IS FORECAST TO MOVE ACROSS THE AREA TUESDAY INTO TUESDAY NIGHT, WHILE PW VALUES INCREASE TO AROUND 1.0-1.5 INCHES. WITH AN INCREASE IN MOISTURE AND WARM TEMPERATURES, THERE IS SOME INSTABILITY FORECAST, WITH MLCAPE VALUES AROUND 500 J/KG, SLIGHTLY NEGATIVE LI VALUES, AND TOTAL TOTAL VALUES NEAR 50. SO AS THE FRONT MOVES THROUGH THE AREA, SCATTERED SHOWERS ARE EXPECTED, ALONG WITH ISOLATED THUNDERSTORMS. THE FRONT SHOULD MOVE ACROSS THE AREA INTO TUESDAY NIGHT, AND SHOWER/THUNDERSTORM ACTIVITY SHOULD MOVE THROUGH WITH THE FRONT AND/OR DIMINISH THROUGH THE NIGHT. AS THE FRONT SLOWLY PASSES THROUGH THE AREA TUESDAY NIGHT INTO WEDNESDAY, IT IS FORECAST TO STALL OUT TO OUR SOUTH THROUGH THE REMAINDER OF THE WEEK, AND MAY END UP WASHING OUT TO OUR SOUTH. WITH THE FRONT TO OUR SOUTH, HIGH PRESSURE FROM THE NORTH WILL TRY TO NOSE ITS WAY INTO THE AREA THROUGH THE END OF THE WEEK. THIS SHOULD KEEP THE WEATHER DRY THROUGH FRIDAY, AND WITH RIDGING BUILDING ALOFT, TEMPERATURES ARE FORECAST TO REMAIN ABOVE NORMAL THROUGH THE END OF THE WEEK. WEDNESDAY MAY BE THE COOLEST DAY WITH A NORTH/NORTHEAST FLOW ACROSS THE AREA WHICH MAY BRING IN COOLER AIR AND KEEP CLOUD COVER IN AS WELL. THE DRY WEATHER SHOULD REMAIN THROUGH FRIDAY NIGHT, BUT ISOLATED SHOWERS MAY RETURN FOR SATURDAY AS RETURN FLOW DEVELOPS ACROSS THE AREA, INCREASING MOISTURE AND DAYTIME INSTABILITY ACROSS THE AREA WHICH COULD LEAD TO A SLIGHT CHANCE OF SHOWERS, ESPECIALLY ACROSS THE WESTERN HALF OF THE AREA. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. 18Z TAFS WERE VFR. REST OF THIS AFTERNOON...CU BASED VFR CIG FROM THE DELAWARE RIVER VALLEY TERMINALS NORTHWESTWARD. WE EXPECT KACY AND KMIV TO PREVAIL WITHOUT A CIG. SOME ISOLATED SHOWERS ARE POSSIBLE NORTHERN AIRPORTS, EVEN MORE ISOLATED THAN YESTERDAY AND WERE NOT INCLUDED. SEA BREEZE FRONT IS MAKING CONSIDERABLE WESTWARD MOVEMENT. AT 20Z IT WAS FROM ABOUT KMIV TO CHATSWORTH IN BURLINGTON COUNTY THRU MOST OF OCEAN COUNTY AND ALONG THE MIDDLESEX AND MONMOUTH COUNTY LINE. PRECEDING IT WINDS ARE LIGHT FROM A WESTERLY COMPONENT AT LESS THAN 10 KNOTS. BY 21Z SEA/BAY BREEZE FRONT SHOULD SHOULD BE THROUGH ALL OF DELAWARE BAY TO KVAY AND KSMQ. BY 23Z MORE CONFIDENT IT SHOULD BE THROUGH DELAWARE AND THE DELAWARE RIVER AIRPORTS INCLUDING KPHL AND BE APPROACHING KLOM AND KDYL. WINDS BEHIND THE SEA BREEZE FRONT SHOULD BE SOUTH TO SOUTHEAST AT AROUND 10 KNOTS. THIS EVENING...THE SEA BREEZE FRONT ADVANCEMENT SHOULD SLOW. IT MIGHT MAKE IT TO KABE. OTHERWISE WINDS WILL BE LIGHT AND VARIABLE WITH SOME VFR ISOLATED/SCATTERED MID LEVEL DEBRIS CLOUDS. OVERNIGHT...CLEAR SKIES AND LIGHT AND VARIABLE WINDS. WE DO NOT HAVE FOG PREDICTED AT THE TERMINALS. CONFIDENCE ABOUT NO FOG AT MORE RURAL AIRPORTS IS MODERATE. AIR MASS HAS BEEN CLEAN AND DEW POINTS ARE NOT RISING THIS AFTERNOON. SUNDAY MORNING INTO EARLY AFTERNOON...VFR NO CIG EXPECTED, LESS CUMULUS CLOUDS THAN TODAY. WINDS BECOMING WEST AT 5 TO 10 KNOTS. ANOTHER SEA BREEZE FRONT IS EXPECTED TO DEVELOP AND WE START THAT AT KACY AT 17Z. OUTLOOK... SUNDAY NIGHT-MONDAY NIGHT...VFR. SOUTHWEST WIND GUSTS AROUND 20 KNOTS MONDAY. TUESDAY-TUESDAY NIGHT...GENERALLY VFR WITH SHOWERS POSSIBLE. SOUTHWEST WIND GUSTS AROUND 20 KNOTS TUESDAY. WEDNESDAY...MOSTLY VFR, POSSIBLE NEAR MVFR CIGS. WEDNESDAY NIGHT-THURSDAY...IMPROVING CONDITIONS TO VFR OVERNIGHT AND CONTINUING THROUGH THURSDAY. && .MARINE... SEAS CONTINUE TO BE SLOWER TO SUBSIDE THAN ANTICIPATED AS THE OFFSHORE PROGRESSION OF THE LOW IS NOT FAST ENOUGH TO NEGATE THE WESTWARD PROPAGATION OF HIGHER SEAS. WAVE WATCH GUIDANCE CONTINUES TO RUN APPROXIMATELY HALF A FOOT TOO LOW. BUOY65 SEAS HAVE BEEN HOLDING AT 4 FEET, SO WE WILL HOLD OFF ON REISSUING A SCA FOR THE MONMOUTH COASTAL WATERS. THE OTHER COASTAL WATERS, WE WILL EXTEND THE SCA FOR SEVERAL MORE HOURS INTO THE NIGHT. ON DELAWARE BAY, IN THE NEAR TERM A STRONG BAY BREEZE WILL WORK ITS WAY UP THE BAY, BUT GUSTS SHOULD BE JUST BELOW SCA CRITERIA. WINDS WILL DECREASE THIS EVENING. WE REMAIN CONFIDENT THAT SUB SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR ON SUNDAY AS THE LOW MOVES FARTHER OFFSHORE AND A HIGH PRESSURE RIDGES OVER THE COASTAL WATERS. A SEA BREEZE FLOW SHOULD DEVELOP AGAIN AND CHANNEL UP DELAWARE BAY. OUTLOOK... SUNDAY NIGHT-THURSDAY...SUB SMALL CRAFT ADVISORY CONDITIONS EXPECTED. HOWEVER, WINDS MAY GUST AROUND 20 KNOTS AND SEAS APPROACH 4 FEET THROUGH THE PERIOD. FRONTAL BOUNDARY IS EXPECTED TO MOVE SOUTH OF THE WATERS ON TUESDAY AND STALL TO OUR SOUTH THROUGH THE END OF THE WEEK. && .FIRE WEATHER... RELATIVE HUMIDITY VALUES AROUND 25-30 PERCENT, ALONG WITH WIND GUSTS OF 20-25 MPH WILL LEAD TO ENHANCED FIRE WEATHER CONCERNS ON MONDAY FOR PORTIONS OF THE FORECAST AREA. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT SUNDAY FOR ANZ452>455. SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ451. && $$ SYNOPSIS...ROBERTSON NEAR TERM...GIGI SHORT TERM...GIGI LONG TERM...ROBERTSON AVIATION...GIGI/ROBERTSON MARINE...GIGI/ROBERTSON FIRE WEATHER...ROBERTSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
102 PM EDT SAT MAY 2 2015 .SYNOPSIS... LOW PRESSURE OFF THE NORTH CAROLINA COAST WILL MOVE FARTHER OUT TO SEA THIS AFTERNOON. AN EXPANSIVE AREA OF HIGH PRESSURE WILL REMAIN IN CONTROL OF THE EASTERN THIRD OF THE COUNTRY THIS WEEKEND. THE CENTER OF THE HIGH WILL SHIFT OFFSHORE SUNDAY NIGHT AND MONDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST MONDAY NIGHT. THIS FRONT IS EXPECTED TO WEAKEN AND STALL OVER THE AREA TUESDAY INTO WEDNESDAY. HIGH PRESSURE BUILDS BACK INTO THE AREA LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CURRENT ESTF WE ADJUSTED MAX TEMPS UPWARD INLAND A COUPLE OF DEGREES BASED ON CURRENT OBS AND TRENDS. WE DIDNT CHANGE LOW POPS MUCH AS INLAND CU ARE SHOWING SOME VERTICAL DEVELOPMENT. SOUNDINGS LOOK CAPPED, SO THUNDER NOT EXPECTED EVENT THOUGH WE DO HAVE SOME CAPE AND SFC BASED LI(S) SHOULD BE DROPPING TO AROUND 0C. HIGH PRESSURE WILL SLOWLY BUILD INTO THE REGION FROM THE W AS LOW PRES OFF THE COAST MOVES AWAY FROM THE REGION. AS A RESULT, MAINLY DRY WX AND WARMING TEMPS ARE IN STORE TODAY. WITH LIGHT FLOW, TEMPS WILL BE COOLER ALG THE CST WHERE A SEABREEZE IS EXPECTED TO DEVELOP AND MOVE PRETTY FAR INLAND AS THE AFTERNOON PROGRESSES. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... THE SFC RIDGE WILL MOVE FURTHER INTO THE REGION TONIGHT AND EXPECT A GENLY CLEAR SKY AND NOT MUCH WIND. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE LARGE-SCALE PLAYERS NEXT WEEK INCLUDE PERSISTENT TROUGHING OVER THE WESTERN CONUS AND DOWNSTREAM RIDGING OVER MUCH OF THE EASTERN CONUS AND WESTERN ATLANTIC. THIS PATTERN WILL RESULT IN WARMER THAN NORMAL TEMPS AND FEW OPPORTUNITIES FOR PRECIPITATION FOR THE MID-ATLANTIC REGION FOR THE LONG-TERM PERIOD. MAX TEMPS GENERALLY RANGE FROM THE MID 70S TO LOWER 80S EACH DAY (EXCEPT COOLER ALONG THE COAST AND IN THE POCONOS). THE CENTER OF THE SURFACE HIGH PRESSURE AND H8 ANTICYCLONE WILL BE POSITIONED OVER THE SOUTHEAST STATES ON SUNDAY. THESE FEATURES WILL PROGRESS DOWNSTREAM TOWARD THE EAST COAST SUNDAY NIGHT AND THEN OVER THE WESTERN ATLANTIC ON MONDAY. SOUTHWESTERLY RETURN FLOW AROUND THE HIGH WILL DRAW EVEN WARMER AND SLIGHTLY MORE HUMID AIR UP THE EASTERN SEABOARD. A COLD FRONT IS EXPECTED TO DROP SOUTHWARD INTO THE REGION TUESDAY MORNING. THE COMBINATION OF UNIDIRECTIONAL W-SW FLOW ALOFT THAT BECOMES ORIENTED PARALLEL TO THE BOUNDARY AND DOWNSTREAM BLOCKING (FROM THE HIGH OVER THE WESTERN ATLANTIC AND CAROLINAS) WILL LIKELY CAUSE THE FRONT TO STALL OVER THE FORECAST AREA THRU WEDNESDAY. THE BOUNDARY WILL ALSO BECOME INCREASINGLY DIFFUSE DURING THIS TIME. THE BEST, IF NOT THE ONLY APPRECIABLE CHANCE FOR PRECIPITATION NEXT WEEK WILL BE TUESDAY-WEDNESDAY. WHILE FORCING FROM THIS DECAYING BOUNDARY ITSELF WILL BE WEAK, WE WILL HAVE TO WATCH FOR MID-LEVEL SHORTWAVE ENERGY THAT EJECTS OUT OF THE SOUTHWEST CONUS TROUGH TO RIDE ATOP THE DOWNSTREAM RIDGE AND EVENTUALLY MOVE INTO OUR AREA SOMETIME DURING THE TUESDAY AFTERNOON- WEDNESDAY MORNING PERIOD. THIS WOULD ENHANCE COVERAGE OF SHOWERS. HOWEVER, THE TIMING AND STRENGTH OF ANY SUCH IMPULSE IS STILL UNCERTAIN THIS FAR OUT, SO POPS WERE KEPT GENERALLY LOW. THE 00Z GUIDANCE PROGS THE GREATER INSTABILITY THAT MAY BE SUFFICIENT FOR CONVECTION TO BE CONFINED TO NEAR THE FRONT OWING TO MOISTURE POOLING ALONG THE BOUNDARY. KEPT CHANCES FOR THUNDERSTORMS LOW AREA WIDE DUE TO UNCERTAINTY IN THE LOCATION OF THE BOUNDARY. THE REMNANTS OF THE OLD FRONTAL BOUNDARY IS FORECAST TO BECOME WASHED OUT ACROSS THE AREA BY WEDNESDAY NIGHT. UPPER RIDGE BUILDING WILL OCCUR OVER THE MIDWEST AND MID ATLANTIC LATE IN THE WEEK. THIS ALLOWS THE WARMTH TO PERSIST ACROSS THE FORECAST AREA THRU THE END OF THE WEEK. MODELS ARE IN GOOD AGREEMENT WITH A CUTOFF LOW FORMING OFF THE SOUTHEAST COAST THURSDAY. WITH WEAK STEERING FLOW UNDERNEATH THE UPPER RIDGE, THE LOW IS NOT EXPECTED TO MAKE MUCH ADVANCEMENT TOWARD OUR AREA, RESULTING IN A DRY FORECAST FOR THURSDAY AND FRIDAY. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. 18Z TAFS ARE VFR. THIS AFTERNOON...CU BASED VFR CIG IS DEVELOPING NORTHWEST HALF OF OUR AREA AND THIS SHOULD CONTINUE. SOME ISOLATED SHOWERS ARE POSSIBLE NORTHWEST AIRPORTS, EVEN MORE ISOLATED THAN YESTERDAY AND WERE NOT INCLUDED. BIGGEST FEATURE WILL BE A SEA BREEZE FRONT THAT IS EXPECTED TO MAKE CONSIDERABLE WESTWARD MOVEMENT. PRECEDING IT WINDS SHOULD BE LIGHT FROM THE WEST TO NORTHWEST AT LESS THAN 10 KNOTS. THE SEA BREEZE FRONT IS ALREADY JUST INLAND IN MONMOUTH AND OCEAN COUNTIES AND BY 21Z SHOULD REACH KMIV-KVAY AND APPROACHING KSMQ. BY 23Z IT SHOULD BE THROUGH MOST OF DELAWARE AND THE DELAWARE RIVER AIRPORTS INCLUDING KPHL AND BE APPROACHING KLOM AND KDYL. WINDS BEHIND THE SEA BREEZE FRONT SHOULD BE SOUTH TO SOUTHEAST AT AROUND 10 KNOTS. THIS EVENING...THE SEA BREEZE FRONT ADVANCEMENT SHOULD SLOW. IT MIGHT MAKE IT TO KABE. OTHERWISE WINDS WILL BE LIGHT AND VARIABLE WITH SOME VFR ISOLATED/SCATTERED MID LEVEL DEBRIS CLOUDS. OVERNIGHT...CLEAR SKIES AND LIGHT AND VARIABLE WINDS. WE DO NOT HAVE FOG PREDICTED AT THE TERMINALS. CONFIDENCE ABOUT NO FOG AT MORE RURAL AIRPORTS IS MODERATE. AIR MASS HAS BEEN CLEAN AND DEW POINTS ARE NOT RISING THIS AFTERNOON. SUNDAY MORNING INTO EARLY AFTERNOON...VFR NO CIG EXPECTED, LESS CUMULUS CLOUDS THAN TODAY. WINDS BECOMING WEST AT 5 TO 10 KNOTS. ANOTHER SEA BREEZE FRONT IS EXPECTED TO DEVELOP AND WE START THAT AT KACY AT 17Z. OUTLOOK... SUNDAY AFTERNOON AND MONDAY...VFR. LIGHT NW WINDS SUNDAY WILL BECOME SWLY AND INCREASE ON MONDAY. GUSTS TO 20 KT POSSIBLE MONDAY AFTERNOON. TUESDAY AND WEDNESDAY...PREDOMINATELY VFR. BRIEF/LOCAL RESTRICTIONS IN SCT SHOWERS AND ISO TSTMS AS A COLD FRONT DROPS SOUTHWARD AND THEN STALLS OVER THE AREA. BEST CHANCE FOR PRECIP WOULD BE TUESDAY AFTERNOON THRU WEDNESDAY MORNING. && .MARINE... WE MADE A COUPLE OF CHANGES TO THE WINDS FOR THIS AFTERNOON AND EVENING BASED ON LATEST 12Z NAM AND SOME OF THE LATEST HRRR AND RAP AS THEY HAVE A DECENT WIND SHIFT/ SEA AND BAY BREEZE FRONT PREDICTED TO DEVELOP. WE WILL EXTEND THE SCA FOR A FEW MORE HOURS AS OBSERVED SEAS ARE ABOUT A FOOT ABOVE WAVE WATCH GUIDANCE. ONCE THIS CURRENT SCA COMES DOWN, NO ADDITIONAL MARINE HEADLINES ARE EXPECTED IN THE NR OR SHORT TERM PDS. OUTLOOK... SUNDAY THROUGH WEDNESDAY...WINDS AND WAVES WILL PREDOMINATELY STAY BELOW SCA CRITERIA. S-SW FLOW WILL INCREASE TO 15-20 KT MONDAY AFTERNOON THRU WEDNESDAY BUT THE WARM AIR ATOP THE COLDER WATERS WILL NOT PROVIDE MUCH OPPORTUNITY FOR STRONGER WINDS ALOFT TO MIX DOWN TO THE SURFACE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ452>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ451. && $$ SYNOPSIS...KLEIN NEAR TERM...GIGI/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...KLEIN AVIATION...GIGI/KLEIN MARINE...GIGI/KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1232 PM EDT SAT MAY 2 2015 .SYNOPSIS... LOW PRESSURE OFF THE NORTH CAROLINA COAST WILL MOVE FARTHER OUT TO SEA TODAY. AN EXPANSIVE AREA OF HIGH PRESSURE WILL REMAIN IN CONTROL OF THE EASTERN THIRD OF THE COUNTRY THIS WEEKEND. THE CENTER OF THE HIGH WILL SHIFT OFFSHORE SUNDAY NIGHT AND MONDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST MONDAY NIGHT. THIS FRONT IS EXPECTED TO WEAKEN AND STALL OVER THE AREA TUESDAY INTO WEDNESDAY. HIGH PRESSURE BUILDS BACK INTO THE AREA LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CURRENT ESTF WE ADJUSTED MAX TEMPS UPWARD INLAND A COUPLE OF DEGREES BASED ON CURRENT OBS AND TRENDS. WE DIDNT CHANGE LOW POPS MUCH AS INLAND CU ARE SHOWING SOME VERTICAL DEVELOPMENT. SOUNDINGS LOOK CAPPED, SO THUNDER NOT EXPECTED EVENT THOUGH WE DO HAVE SOME CAPE AND SFC BASED LI(S) SHOULD BE DROPPING TO AROUND 0C. HIGH PRESSURE WILL SLOWLY BUILD INTO THE REGION FROM THE W AS LOW PRES OFF THE COAST MOVES AWAY FROM THE REGION. AS A RESULT, MAINLY DRY WX AND WARMING TEMPS ARE IN STORE TODAY. WITH LIGHT FLOW, TEMPS WILL BE COOLER ALG THE CST WHERE A SEABREEZE IS EXPECTED TO DEVELOP AND MOVE PRETTY FAR INLAND AS THE AFTERNOON PROGRESSES. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... THE SFC RIDGE WILL MOVE FURTHER INTO THE REGION TONIGHT AND EXPECT A GENLY CLEAR SKY AND NOT MUCH WIND. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE LARGE-SCALE PLAYERS NEXT WEEK INCLUDE PERSISTENT TROUGHING OVER THE WESTERN CONUS AND DOWNSTREAM RIDGING OVER MUCH OF THE EASTERN CONUS AND WESTERN ATLANTIC. THIS PATTERN WILL RESULT IN WARMER THAN NORMAL TEMPS AND FEW OPPORTUNITIES FOR PRECIPITATION FOR THE MID-ATLANTIC REGION FOR THE LONG-TERM PERIOD. MAX TEMPS GENERALLY RANGE FROM THE MID 70S TO LOWER 80S EACH DAY (EXCEPT COOLER ALONG THE COAST AND IN THE POCONOS). THE CENTER OF THE SURFACE HIGH PRESSURE AND H8 ANTICYCLONE WILL BE POSITIONED OVER THE SOUTHEAST STATES ON SUNDAY. THESE FEATURES WILL PROGRESS DOWNSTREAM TOWARD THE EAST COAST SUNDAY NIGHT AND THEN OVER THE WESTERN ATLANTIC ON MONDAY. SOUTHWESTERLY RETURN FLOW AROUND THE HIGH WILL DRAW EVEN WARMER AND SLIGHTLY MORE HUMID AIR UP THE EASTERN SEABOARD. A COLD FRONT IS EXPECTED TO DROP SOUTHWARD INTO THE REGION TUESDAY MORNING. THE COMBINATION OF UNIDIRECTIONAL W-SW FLOW ALOFT THAT BECOMES ORIENTED PARALLEL TO THE BOUNDARY AND DOWNSTREAM BLOCKING (FROM THE HIGH OVER THE WESTERN ATLANTIC AND CAROLINAS) WILL LIKELY CAUSE THE FRONT TO STALL OVER THE FORECAST AREA THRU WEDNESDAY. THE BOUNDARY WILL ALSO BECOME INCREASINGLY DIFFUSE DURING THIS TIME. THE BEST, IF NOT THE ONLY APPRECIABLE CHANCE FOR PRECIPITATION NEXT WEEK WILL BE TUESDAY-WEDNESDAY. WHILE FORCING FROM THIS DECAYING BOUNDARY ITSELF WILL BE WEAK, WE WILL HAVE TO WATCH FOR MID-LEVEL SHORTWAVE ENERGY THAT EJECTS OUT OF THE SOUTHWEST CONUS TROUGH TO RIDE ATOP THE DOWNSTREAM RIDGE AND EVENTUALLY MOVE INTO OUR AREA SOMETIME DURING THE TUESDAY AFTERNOON- WEDNESDAY MORNING PERIOD. THIS WOULD ENHANCE COVERAGE OF SHOWERS. HOWEVER, THE TIMING AND STRENGTH OF ANY SUCH IMPULSE IS STILL UNCERTAIN THIS FAR OUT, SO POPS WERE KEPT GENERALLY LOW. THE 00Z GUIDANCE PROGS THE GREATER INSTABILITY THAT MAY BE SUFFICIENT FOR CONVECTION TO BE CONFINED TO NEAR THE FRONT OWING TO MOISTURE POOLING ALONG THE BOUNDARY. KEPT CHANCES FOR THUNDERSTORMS LOW AREA WIDE DUE TO UNCERTAINTY IN THE LOCATION OF THE BOUNDARY. THE REMNANTS OF THE OLD FRONTAL BOUNDARY IS FORECAST TO BECOME WASHED OUT ACROSS THE AREA BY WEDNESDAY NIGHT. UPPER RIDGE BUILDING WILL OCCUR OVER THE MIDWEST AND MID ATLANTIC LATE IN THE WEEK. THIS ALLOWS THE WARMTH TO PERSIST ACROSS THE FORECAST AREA THRU THE END OF THE WEEK. MODELS ARE IN GOOD AGREEMENT WITH A CUTOFF LOW FORMING OFF THE SOUTHEAST COAST THURSDAY. WITH WEAK STEERING FLOW UNDERNEATH THE UPPER RIDGE, THE LOW IS NOT EXPECTED TO MAKE MUCH ADVANCEMENT TOWARD OUR AREA, RESULTING IN A DRY FORECAST FOR THURSDAY AND FRIDAY. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS ARE EXPECTED THRU THE TAF PD AS HIGH PRES BUILDS IN FROM THE W. THERE WILL BE SOME LINGERING SC AT TIMES THRU THE DAY BEFORE THE SKY BECOMES MAINLY CLR OVERNIGHT. WIND WILL SHIFT FROM NELY TO ELY AND EVENTUALLY S DURG THE DAY AND BECOME LIGHT OVERNIGHT. SPEEDS WILL REMAIN LESS THAN 10 KT. A SEA BREEZE FRONT IS EXPECTED TO WORK ITS WAY INLAND FROM THE CST DURG THE AFTN. OUTLOOK... SUNDAY AND MONDAY...VFR. LIGHT NW WINDS SUNDAY WILL BECOME SWLY AND INCREASE ON MONDAY. GUSTS TO 20 KT POSSIBLE MONDAY AFTERNOON. TUESDAY AND WEDNESDAY...PREDOMINATELY VFR. BRIEF/LOCAL RESTRICTIONS IN SCT SHOWERS AND ISO TSTMS AS A COLD FRONT DROPS SOUTHWARD AND THEN STALLS OVER THE AREA. BEST CHANCE FOR PRECIP WOULD BE TUESDAY AFTERNOON THRU WEDNESDAY MORNING. && .MARINE... WE MADE A COUPLE OF CHANGES TO THE WINDS FOR THIS AFTERNOON AND EVENING BASED ON LATEST 12Z NAM AND SOME OF THE LATEST HRRR AND RAP AS THEY HAVE A DECENT WIND SHIFT/ SEA AND BAY BREEZE FRONT PREDICTED TO DEVELOP. WE WILL EXTEND THE SCA FOR A FEW MORE HOURS AS OBSERVED SEAS ARE ABOUT A FOOT ABOVE WAVE WATCH GUIDANCE. ONCE THIS CURRENT SCA COMES DOWN, NO ADDITIONAL MARINE HEADLINES ARE EXPECTED IN THE NR OR SHORT TERM PDS. OUTLOOK... SUNDAY THROUGH WEDNESDAY...WINDS AND WAVES WILL PREDOMINATELY STAY BELOW SCA CRITERIA. S-SW FLOW WILL INCREASE TO 15-20 KT MONDAY AFTERNOON THRU WEDNESDAY BUT THE WARM AIR ATOP THE COLDER WATERS WILL NOT PROVIDE MUCH OPPORTUNITY FOR STRONGER WINDS ALOFT TO MIX DOWN TO THE SURFACE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ452>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ451. && $$ SYNOPSIS...KLEIN NEAR TERM...GIGI/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...KLEIN AVIATION...KLEIN/NIERENBERG MARINE...GIGI/KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS LINCOLN IL
256 PM CDT SAT MAY 2 2015 .SHORT TERM...(TONIGHT) ISSUED AT 255 PM CDT SAT MAY 2 2015 A WEAK SHORT WAVE OVER WESTERN IA WILL TRACK EAST TO THE IL/IA BORDER BY MIDNIGHT AND WEAKEN AS IT MOVES ACROSS CENTRAL AND NORTHERN IL OVERNIGHT. AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS OVER NORTHERN MO AND SOUTHERN IA WILL CONTINUE TO TRACK EASTWARD INTO WEST CENTRAL IL EARLY THIS EVENING BETWEEN 6-8 PM AND INTO CENTRAL IL LATER THIS EVENING AND OVERNIGHT AS SHOWERS BECOME MORE ISOLATED. HAVE 20-30% CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS FROM I-55 NW AFTER SUNSET TONIGHT AND LINGERING ISOLATED LIGHT SHOWERS UNTIL MID SUNDAY MORNING NORTH OF I-72 UNTIL WEAKENING SHORT WAVE PASSES EAST OF IL INTO WESTERN IN BY MIDDAY SUNDAY. MID AND HIGH CLOUDS WILL CONTINUE TO INCREASE FROM THE WEST LATE THIS AFTERNOON AND EVENING WITH SOUTHEAST IL SEEING LESS CLOUD COVER TONIGHT SINCE CLOSER TO HIGH PRESSURE RIDGE OVER SOUTHEAST STATES. LOWS TONIGHT IN THE LOW TO MID 50S WITH COOLEST READINGS NEAR WABASH RIVER WHERE LIGHER WINDS AND LESS CLOUD COVER TONIGHT. SSW WINDS 7- 14 MPH AND GUSTS 15-20 MPH THIS AFTERNOON TO DIMINISH LESS THAN 10 MPH AFTER SUNSET AND VEER SSE. && .LONG TERM...(SUNDAY THROUGH SATURDAY) ISSUED AT 255 PM CDT SAT MAY 2 2015 IOWA SHORTWAVE FORECAST BY MODELS TO TRACK ACROSS THE AREA OVERNIGHT AND INTO THE MORNING HOURS OF SUNDAY BRINGING ISOLATED SHOWERS TO PARTS OF THE FORECAST AREA. SOUNDINGS STILL SHOWING A VERY DRY PROFILE BELOW 850 MB INTO SUNDAY MORNING BEFORE THE WAVE SHIFTS OFF TO OUR EAST DURING THE MORNING. WILL KEEP SLIGHTS GOING FOR A FEW HOURS IN THE MORNING BEFORE THE WAVE MOVES OUT OF THE AREA. OUR ATTENTION THEN TURNS TO A NORTHERN STREAM SHORTWAVE THAT WILL DRAG A COLD FRONT SOUTHEAST INTO THE LOWER GREAT LAKES LATE SUNDAY AND INTO MONDAY INCREASING THE CHANCES FOR MORE WIDESPREAD SHOWERS AND STORMS...ESPECIALLY OVER THE NORTHERN HALF OF THE FORECAST AREA WHERE THE BOUNDARY IS FORECAST TO BECOME STATIONARY. AFTER OUR SLIGHT CHANCES SUNDAY MORNING...THE REST OF THE DAY LOOKS QUIET AND WARM WITH A GUSTY SOUTH TO SOUTHWEST WIND HELPING TO PUSH AFTERNOON TEMPS INTO THE UPPER 70S TO LOWER 80S. POPS START TO RAMP UP SUNDAY NIGHT ACROSS THE FAR NORTHWEST AS THE BOUNDARY EDGES SLOWLY SOUTHEAST WITH MODELS TRENDING SLOWER WITH THE FRONTAL BOUNDARY AND QPF ALONG IT. MAY HAVE TO SLOW THE ONSET OF THE SHOWERS EVEN MORE IF THESE TRENDS CONTINUE. BETTER LOW LEVEL JET SUPPORT AND 850 MB THETA-E ADVECTION REMAINS OUT TO OUR NORTHWEST LATE SUNDAY NIGHT WITH MOST MODELS SUGGESTING THAT A CLUSTER OF STORMS...AT LEAST WHAT`S LEFT OF THEM...WILL APPROACH OUR FAR NORTHWEST COUNTIES WELL AFTER MIDNIGHT SUNDAY NIGHT. THE SHOWER AND THUNDERSTORM CHANCES WILL CONTINUE TO SPREAD SLOWLY SOUHTEAST ON MONDAY AND INTO MONDAY NIGHT WITH THE HIGHER THREAT BEING AGAIN WHERE THE BOUNDARY IS EXPECTED TO BECOME STATIONARY... WHICH AT THIS TIME LOOKS TO BE NORTH OF I-72. FORECAST SOUNDINGS SHOWING MIXED LAYER CAPES OF AROUND 1500 J/KG MONDAY AFTERNOON INTO EARLY MONDAY EVENING WITH THE STRONGER 500 MB WIND FLOW TO OUR NORTH WITH 30-35 KTS FORECAST. SPC HAS A LARGE AREA OF MARGINAL RISK FOR SEVERE STORMS MONDAY AFTERNOON AND EVENING STRETCHING FROM THE SOUTHERN PLAINS UP ACROSS THE NORTHERN HALF OF OUR CWA. SEVERE PARAMETERS BORDERLINE AT THIS TIME BUT WITH THE BOUNDARY IN THE AREA AND FORECAST CONVECTIVE TEMPS AROUND 80...MULTI-CELL STORMS SHOULD DEVELOP DURING THE AFTERNOON AND CONTINUE INTO THE EVENING WITH THE POSSIBILITY FOR SOME GUSTY WINDS...HAIL AND HEAVY RAINFALL WITH SOME OF THE MORE ORGANIZED CLUSTERS OF STORMS THAT FORM ALONG THE STALLED FRONTAL BOUNDARY. MODELS SUGGEST THE BOUNDARY WILL SHIFT NORTH OF THE AREA STARTING ON TUESDAY AS UPPER LEVEL HEIGHTS BUILD IN RESPONSE TO A RATHER VIGOROUS UPPER WAVE THAT WILL BE PUSHING ACROSS THE SOUTHERN ROCKIES AND EVENTUALLY SWING NORTHEAST INTO THE PLAINS BY MID TO LATE IN THE UPCOMING WORK WEEK. WILL INDICATE A BIT OF A LULL IN THE SHOWER AND STORM CHANCES UNTIL LATE THURSDAY OR FRIDAY WHEN THE WAVE WILL APPROACH OUR AREA. TEMPERATURES LOOK TO BE ABOVE NORMAL THRU THE WORK WEEK WITH AFTERNOON HIGHS CLIMBING INTO THE UPPER 70S TO LOWER 80S...WHILE EARLY MORNING LOWS ONLY DROP OFF INTO THE UPPER 50S TO LOWER 60S TUESDAY MORNING...WITH MOST OF OUR AREA SEEING LOW TEMPERATURES IN THE LOW TO MID 60S FOR THE REMAINDER OF THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1255 PM CDT SAT MAY 2 2015 VFR CONDITIONS ARE FORECAST TO CONTINUE ACROSS THE CENTRAL IL AIRPORTS THROUGH SUNDAY. SCATTERED TO BROKEN MID/HIGH CLOUDS ABOVE 7K FT WILL SPREAD EAST ACROSS CENTRAL IL THIS AFTERNOON. WEAK SHORT WAVE OVER WESTERN IA TO TRACK EAST TOWARD THE IL/IA BORDER BY MIDNIGHT TONIGHT AND WEAKEN FURTHER. VCSH AT PIA AFTER 02Z AND AS FAR EAST AT I-55 AT BMI AND SPI AFTER 04Z TONIGHT. LATEST HRRR AND RAP MODELS SHOW ISOLATED SHOWERS THIS FAR EAST DURING 2ND HALF OF EVENING WHILE NAM MODEL (WHICH INITIALIZED TOO DRY) KEEPS CENTRAL IL DRY NEXT 24 HOURS. SSW WINDS 9-13 KTS THIS AFTERNOON TO BE SSE 4-8 KTS TONIGHT AND SSW 9-13 KTS SUNDAY WITH FEW-SCT CUMULUS CLOUDS 5-6 KFT AND SOME BROKEN MID LEVEL CLOUDS AT OR ABOVE 10K FT. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...07 LONG TERM...SMITH AVIATION...07
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1255 PM CDT SAT MAY 2 2015 .UPDATE... ISSUED AT 1045 AM CDT SAT MAY 2 2015 FORECAST GENERALLY ON TRACK THOUGH WILL NEED TO UPDATE FOR MORE CLOUD COVER THIS AFTERNOON ESPECIALLY WESTERN AREAS. SHOWERS AND ISOLATED THUNDERSTORMS SHOULD STAY WEST OF CENTRAL IL THROUGH SUNSET PER LATEST HIGH RESOLUTION MODELS. MILDER HIGHS IN THE MID TO UPPER 70S THIS AFTERNOON WITH PARTLY TO MOSTLY SUNNY SKIES AND SOUTHWEST WINDS 5-15 MPH THIS AFTERNOON. 1022 MB HIGH PRESSURE RIDGE OVER KY AND TN RIVER VALLEY WILL SHIFT SE OF KY/TN BY THIS EVENING WHILE WEAK UPPER LEVEL RIDGE INTO IL TODAY. THIS WILL KEEP CENTRAL AND SOUTHEAST IL DRY TODAY WITH INCREASING SW WINDS BRINGING IN MILDER TEMPERATURES. WEAK SHORT WAVE NEAR IA/NE BORDER TO TRACK EAST INTO EASTERN IA BY MID EVENING WITH SHOWERS AND ISOLATED THUNDERSTORMS SPREADING EASTWARD ACROSS SOUTHERN IA AND NORTHERN MO THIS AFTERNOON, AND INTO WEST CENTRAL IL AFTER SUNSET. && .SHORT TERM...(TODAY) ISSUED AT 331 AM CDT SAT MAY 2 2015 A SHORTWAVE HIGH PRESSURE RIDGE EMBEDDED IN WESTERLY FLOW ALOFT WILL BE THE DOMINATING WEATHER FEATURE TODAY...PROMOTING GENERAL SUBSIDENCE AND LIGHT CLOUD COVER THROUGH THE DAY. WITH SLOWLY MOISTENING LOWER LEVELS...THERE SHOULD BE ENOUGH MOISTURE FOR A SHALLOW SCATTERED CUMULUS LAYER DEVELOPING IN LATE MORNING THROUGH AFTERNOON. HIGH CLOUD COVER ASSOCIATED WITH AN APPROACHING UPPER LEVEL DISTURBANCE WILL START TO SPREAD INTO CENTRAL IL LATE IN THE AFTERNOON. RELATIVELY LIGHT SOUTHWESTERLY WINDS AROUND 6 TO 10 MPH EXPECTED TODAY...ALONG WITH HIGH TEMPERATURES REACHING THE MID 70S. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 331 AM CDT SAT MAY 2 2015 HIGH PRESSURE RIDGE AXIS FROM THE WESTERN GULF COAST UP INTO THE GREAT LAKES THIS MORNING KEEPING THE WEATHER MILD IN THE SHORT TERM THROUGH THE WEEKEND. QUASI ZONAL FLOW OVER THE WESTERN HALF OF THE COUNTRY AND INTO THE PLAINS SLOWLY SHIFTS TO THE MIDWEST LATER IN THE WEEKEND. WITH THE ZONAL FLOW ALOFT...A FRONT SETTLES INTO THE REGION AND STALLS OUT...BECOMING A FOCUS FOR STORMS AND PRECIP FOR THE START OF THE WORK WEEK. PRECIP CHANCES HOLDING ON UNTIL A RIDGE BEGINS TO BUILD INTO THE MIDWEST FROM THE SOUTHEASTERN CONUS. INFLUENCE OF THE RIDGE ERODING THE SOUTHERN EXTENT OF THE SHOWERS AT LEAST TUES NIGHT THROUGH WED NIGHT. MODELS SHIFT GEARS AGAIN ON THE OTHER SIDE OF MIDWEEK, GOING TO A MORE SOUTHWESTERLY FLOW AND AN ACTIVE WEATHER PATTERN AS WAVES CONTINUE TO RIPPLE AROUND THE SWRN LOW AND INTO THE MIDWEST. A RATHER WET FORECAST OVERALL, WITH SEVERAL DIFFERENT PATTERNS ESTABLISHING THEMSELVES...AND KEEPING SHOWERS AND THUNDERSTORMS IN THE OUTLOOK. NOT MUCH IN THE WAY OF MODEL DIFFERENCES OVERALL AND GUIDANCE SEEMS TO BE TRENDING WARMER. ECMWF 850MB TEMPS STAYING IN THE 11-13C THROUGH MIDWEEK...EVEN WARMER TO WRAP UP THE WORK WEEK...BUT THOSE WARMER TEMPS ALOFT WILL BE COUNTERED BY PRECIP IN THE MORE ACTIVE SWRLY PATTERN. OVERALL, CONCERN IN THE FORECAST CENTERS ON THE LOCATION OF THE FRONT STALLING OUT AND THE SUBSEQUENT FOCUS FOR THE PRECIPITATION/TRAINING. NOT MUCH IN THE WAY OF SEVERE WEATHER EXPECTED AT THIS POINT...BUT PROLONGED RAINFALL MAY NEED TO BE WATCHED A BIT FOR MON AND TUES, PARTICULARLY IN THE NORTHERN HALF OF THE STATE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1255 PM CDT SAT MAY 2 2015 VFR CONDITIONS ARE FORECAST TO CONTINUE ACROSS THE CENTRAL IL AIRPORTS THROUGH SUNDAY. SCATTERED TO BROKEN MID/HIGH CLOUDS ABOVE 7K FT WILL SPREAD EAST ACROSS CENTRAL IL THIS AFTERNOON. WEAK SHORT WAVE OVER WESTERN IA TO TRACK EAST TOWARD THE IL/IA BORDER BY MIDNIGHT TONIGHT AND WEAKEN FURTHER. VCSH AT PIA AFTER 02Z AND AS FAR EAST AT I-55 AT BMI AND SPI AFTER 04Z TONIGHT. LATEST HRRR AND RAP MODELS SHOW ISOLATED SHOWERS THIS FAR EAST DURING 2ND HALF OF EVENING WHILE NAM MODEL (WHICH INITIALIZED TOO DRY) KEEPS CENTRAL IL DRY NEXT 24 HOURS. SSW WINDS 9-13 KTS THIS AFTERNOON TO BE SSE 4-8 KTS TONIGHT AND SSW 9-13 KTS SUNDAY WITH FEW-SCT CUMULUS CLOUDS 5-6 KFT AND SOME BROKEN MID LEVEL CLOUDS AT OR ABOVE 10K FT. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...07 SHORT TERM...ONTON LONG TERM...HJS AVIATION...07
AREA FORECAST DISCUSSION
NWS TOPEKA KS
406 PM CDT Sat May 2 2015 .SHORT TERM...(This Evening through Sunday) Issued at 404 PM CDT SAT MAY 2 2015 19Z water vapor imagery shows a shortwave moving across IA while 500MB profiler data suggests a more subtle wave has passed through eastern KS. Meanwhile a weak mid level ridge has propagated east and is centered over the TX big bend region with the mean westerlies remain north along the Canadian boarder. At the surface, high pressure over the southeast U.S. and low pressure in the northern plains has favored continued moisture advection with southerly winds bringing mid 50s dewpoints into the central plains. For tonight and Sunday, large scale forcing continues to be absent from the pattern. However models hint at the possibility for sporadic shower activity as early as this evening. The HRRR and RAP are the most optimistic in generating the shower activity. It appears the evening QPF is driven by warm air advection and isentropic upglide around 700MB. However RAP soundings suggest moisture will be rather limited in this layer. Because of this and the general subsidence behind the subtle wave, am not convinced showers will redevelop across central KS this evening. There are also signs that another subtle wave could come out of the CO Rockies late tonight and Sunday morning with some elevated light shower activity. There is a more organized signal in the isentropic surfaces of a shallow layer of lift Sunday morning. With bases at 10 KFT and little if any instability above this layer, am not sure any precip would amount to much and it end up being mainly virga. So have maintained a dry forecast for now, but there could be some light hit or miss precip with not much impact. Thanks for the collaboration EAX and ICT. Southerly winds and increased low level moisture should help keep lows tonight around 60 degrees. Increasing clouds from the west should also help keep overnight lows mild. With continued southerly winds, models continue the warming trend at 850MB with good mixing. Therefore have maintained highs in the lower and mid 80s. However if there is elevated shower activity, the forecast may be to warm for areas that remain cloudy. .LONG TERM...(Sunday Night through Saturday) Issued at 404 PM CDT SAT MAY 2 2015 Several opportunities for precipitation remain present through the forecast, with challenges on where and when the higher chances will be being the main challenge. The main trend in the nearer periods is the trend for a farther north settling of the cold front as it enters the area. Getting the front much past the northwest counties could be difficult with little/no additional frontogenesis from convection through Sunday afternoon along it and west to southwest flow over it. Have continued to taper precip chances, especially in the south into Monday night. There continues to be at least minor potential for severe weather and perhaps training storms near the boundary. NAM continues to look overdone with low level moisture and thus CAPE, but values near 2000 J/kg seem possible along the front with flow aloft nearly parallel to the boundary with slow cell motions and PWs near 1.5", more likely late Monday into Monday night. The front/effective front remains on track to mix back north Tuesday with some drier air moving in through the day, but attention then turns to the southwest as an upper wave remains on track to push slowly northeast through the Central Plains Tuesday night through Wednesday night. Models are fairly consistent with better upper forcing to the northwest and southeast, but also with widespread convection developing to the south-southwest and translating through late Tuesday night into Wednesday. Beyond Wednesday night, there continues to be indications of a weak boundary near to just west of the area with continued moisture availability into the area into Saturday. && .AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon) Issued at 1224 PM CDT SAT MAY 2 2015 Improving conditions will be the trend for the rest of today outside of the increase in winds. Gusts are likely as clouds dissipate and mixing takes place. Wind shear conditions could be present tomorrow morning with the LLJ increasing over the region, but did leave mention out of the TAFs for now. There is the possibility also for a round of showers or elevated convection late in the TAF period associated with a vorticity max moving out of the Central Rockies affecting all the terminals. Timing on this would be uncertain at this point but will be something to pay attention to for longer term planning. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Drake
AREA FORECAST DISCUSSION
NWS GOODLAND KS
235 PM MDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 157 PM MDT SAT MAY 2 2015 LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW WESTERLY ZONAL FLOW IN PLACE FROM THE GREAT BASIN ACROSS THE CENTRAL ROCKIES INTO THE MISSISSIPPI VALLEY WITH EMBEDDED H5/H7 SHORTWAVE TROUGHS MOVING THROUGH THE MEAN FLOW. AT THE SURFACE LEE TROUGH HAS DEVELOPED ACROSS EASTERN COLORADO WITH A MEAN SURFACE TROUGH FROM THE NE PANHANDLE AND ALONG THE COLORADO BORDER. THUNDERSTORM ACTIVITY HAS ALREADY DEVELOPED ALONG THE CHEYENNE RIDGE AND HIGHER TERRAIN IN COLORADO. THIS AFTERNOON-TONIGHT...RAP ANALYSIS (WHICH IS IN LINE WITH EARLIER NAM) SHOWS 2000 J/KG OF SB CAPE IN PLACE ALONG AND AHEAD OF THE SURFACE TROUGH...CENTERED OVER OUR CWA. CINH APPEARS TO BE WEAKENING...HOWEVER ONLY SOME SHALLOW CU HAVE FORMED SO FAR THIS AFTERNOON. AS MID LEVEL VORTICITY ROTATES FROM THE CENTRAL ROCKIES INTO EASTERN COLORADO I WOULD EXPECT DEVELOPMENT TO SPREAD EAST WHICH IS IN LINE WITH SYNOPTIC SCALE GUIDANCE. HRRR/RAP BOTH INDICATE ISOLATED ACTIVITY DEVELOPING ALONG AND EAST OF THE SURFACE TROUGH OVER OUR CWA WITH ADDITIONAL ACTIVITY SPREADING IN FROM THE WEST. BULK SHEER/HELICITY ARE NOT VERY IMPRESSIVE AT THIS POINT WHERE BETTER INSTABILITY IS IN PLACE (WEST). MOISTURE PROFILES ARE NOT PARTICULARLY IMPRESSIVE...AND THIS COULD LIMIT COVERAGE TO ISOLATE/SCATTERED. BETTER PRECIP SIGNAL AND INSTABILITY ARE SHOW IN IN THE LOWER SHEER ENVIRONMENT...WHERE PULSE TYPE THUNDERSTORMS WOULD BE MORE LIKELY. STEEP MID LEVEL LAPSE RATES AND MODERATE INSTABILITY COULD SUPPORT STRONGER UPDRAFTS/CORES...WITH LARGE HAIL/SEVERE WINDS POSSIBLE. DCAPE VALUES 1000-1500 J/KG AND IN HIGHER TD DEPRESSIONS (MAINLY WEST) DO RAISE A CONCERN FOR INCREASED MICROBURST POTENTIAL WITH SOME OF THESE STORMS. IF ANY OF THIS ACTIVITY WAS TO MOVE INTO THE EASTERN CWA IT COULD BECOME MORE ORGANIZED WITH INCREASING SPEED SHEER (35KT BULK EFFECTIVE SHEER AROUND 00Z). AS THE SUN SETS AND WE LOOSE DAYTIME HEATING ANY LINGERING ACTIVITY SHOULD QUICKLY WEAKEN AS THERE IS ELEVATED CAPE LATE AND ONLY A WEAK LLJ IN PLACE OVERNIGHT. SUNDAY...ANOTHER VERY WARM DAY IS EXPECTED AS SURFACE TROUGH DEEPENS A LITTLE OVER THE CWA AND WAA INCREASES OVER THE CWA. THIS IS IN RESPONSE TO A STRONGER SHORTWAVE TROUGH MOVING INTO THE NORTHERN PLAINS AND A COLD FRONT DROPPING SOUTH INTO NORTHERN NEBRASKA. HIGHS SHOULD BE SIMILAR TO TODAY WITH MOST IN THE 80S...AND A FEW LOCATIONS APPROACHING 90 (MAINLY MCCOOK/HILL CITY). SURFACE TROUGH WILL SHIFT JUST A LITTLE BIT EAST AND LOW LEVEL MOISTURE RETURN COULD BRING HIGHER TD VALUES INTO NORTH CENTRAL KS. NAM MAY BE A LITTLE HIGH...BUT EITHER WAY THIS BETTER BL MOISTURE WILL SUPPORT HIGHER CAPE VALUES IN THE AFTERNOON IN THE 2000-2500 J/KG RANGE. SHEER MAY ALSO BE A LITTLE BIT BETTER WHERE GOOD INSTABILITY IS IN PLACE THAN TODAY...SO THERE MAY BE A BIGGER THREAT FOR MORE ORGANIZE THUNDERSTORM DEVELOPMENT IF ANYTHING IS TO DEVELOP IN THE AFTERNOON. THUNDERSTORM ACTIVITY IS SHOWN TO INITIATE PRIMARILY ALONG SURFACE TROUGH IN THE AFTERNOON. HOWEVER WITH DRIER MOISTURE PROFILES AGAIN IN PLACE COVERAGE COULD BE LIMITED AT LEAST UNTIL LATER WHEN BETTER LARGE SCALE FORCING/DEEPER MOISTURE MOVINGS IN TO THE REGION FROM THE NORTHWEST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 233 PM MDT SAT MAY 2 2015 UPPER LEVEL FLOW WILL BE SOUTHWEST FROM SUNDAY NIGHT THROUGH TUESDAY AHEAD OF A LOW MOVING EAST FROM THE DESERT SOUTHWEST INTO THE CENTRAL AND SOUTHERN ROCKIES. A SURFACE TROUGH NEAR NORTHWEST KANSAS WILL MOVE EAST MONDAY. HIGH PRESSURE WILL BUILD INTO NORTHWEST KANSAS MONDAY NIGHT AND TUESDAY. AN AREA OF LOW PRESSURE WILL MOVE INTO COLORADO TUESDAY. A SHORTWAVE SHOULD AFFECT THE FA SUNDAY EVENING AND INITIATE STORMS NEAR THE SURFACE TROUGH OVER NORTHEAST COLORADO INTO SOUTHWEST NEBRASKA. PLAN TO USE HIGH CHANCE POPS IN THAT AREA WITH LOWER CHANCE POPS ELSEWHERE ACROSS THE FA. PLAN TO KEEP HIGHER CHANCE POPS ACROSS THE NORTHERN FA AS STORMS DRIFT NORTHEAST INTO THE FA OVERNIGHT. THERE SHOULD BE A LULL MONDAY MORNING BEHIND THE EXITING WAVE. POPS WILL INCREASE TO HIGH CHANCE MONDAY AFTERNOON AND EVENING AS THE NEXT SHORTWAVE COMES THROUGH. MOISTURE AND DYNAMICS LOOK GOOD FOR MONDAY NIGHT SO WILL CONTINUE HIGH CHANCE AND LIKELY POPS. GOOD DYNAMICS AND MOISTURE CONTINUE TO STREAM ACROSS THE FA TUESDAY AS THE MAIN TROUGH MOVES INTO THE AREA. PRECIPITABLE WATER VALUES ACROSS THE FA FOR TUESDAY RANGE FROM 1.0 TO 1.2 INCHES. PLAN TO CONTINUE LIKELY AND DEFINITE POPS. MIN TEMPERATURES THROUGH MONDAY NIGHT SHOULD COOL INTO THE MID 40S IN EASTERN COLORADO TO THE MID 50S IN THE EASTERN FA. MAX TEMPERATURES MONDAY SHOULD RANGE FROM THE LOWER 60S IN EASTERN COLORADO TO THE LOWER 70S IN THE EASTERN FA. IN THE EXTENDED...(TUESDAY NIGHT THROUGH SATURDAY)...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE CENTRAL PLAINS TUESDAY NIGHT AND WEDNESDAY AND THEN LIFT OUT OF THE AREA WEDNEDAY NIGHT. GOOD DYNAMICS AND MOISTURE SUPPORT HIGH POPS THROUGH WEDNESDAY. POPS WILL DECREASE TO CHANCE THURSDAY AND FRIDAY BEHIND THE EXITING TROUGH WITH A COUPLE OF SHORTWAVES IN SOUTHWEST FLOW PRODUCING STORMS. POPS WILL INCREASE AGAIN SATURDAY AS THE NEXT UPPER LEVEL TROUGH BEGINS IMPACTING THE CENTRAL PLAINS. MIN TEMPERATURES SHOULD RANGE FROM 45 TO 55 THROUGH FRIDAY NIGHT WITH COOLER READINGS IN EASTERN COLORADO. MAX TEMPERATURES WILL GENERALLY WARM TO THE 70S EACH DAY WITH SOME UPPER 60S POSSIBLE IN EASTERN COLORADO AND NEAR 80 IN THE EASTERN FA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1137 AM MDT SAT MAY 2 2015 VFR CONDITIONS AND WINDS LESS THAN 12KT SHOULD PREVAIL AT BOTH KGLD AND KMCK TERMINALS THROUGH THE TAF PERIOD. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING ALONG SURFACE TROUGH THIS AFTERNOON AND EVENING. BETTER COVERAGE SHOULD REMAIN ALONG COLORADO STATE LINE WITH ACTIVITY TRANSITIONING EAST AND SOUTH BASED ON SHORT RANGE GUIDANCE. THIS PLACES ACTIVITY WITHIN THE VICINITY OF KGLD...BUT LIKELY SOUTH OF KMCK. POTENTIAL EXISTS FOR STRONG/SEVERE THUNDERSTORMS WITH HAIL/STRONG WINDS WITH SOME OF THESE STORMS...SO WILL NEED TO AMEND IF IT LOOKS LIKE ANY PARTICULAR STORM WILL IMPACT A TERMINAL. COVERAGE/CONFIDENCE TOO LOW TO INCLUDE MORE THAN VCTS AT KGLD AT THIS TIME. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...FS AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
157 PM MDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 157 PM MDT SAT MAY 2 2015 LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW WESTERLY ZONAL FLOW IN PLACE FROM THE GREAT BASIN ACROSS THE CENTRAL ROCKIES INTO THE MISSISSIPPI VALLEY WITH EMBEDDED H5/H7 SHORTWAVE TROUGHS MOVING THROUGH THE MEAN FLOW. AT THE SURFACE LEE TROUGH HAS DEVELOPED ACROSS EASTERN COLORADO WITH A MEAN SURFACE TROUGH FROM THE NE PANHANDLE AND ALONG THE COLORADO BORDER. THUNDERSTORM ACTIVITY HAS ALREADY DEVELOPED ALONG THE CHEYENNE RIDGE AND HIGHER TERRAIN IN COLORADO. THIS AFTERNOON-TONIGHT...RAP ANALYSIS (WHICH IS IN LINE WITH EARLIER NAM) SHOWS 2000 J/KG OF SB CAPE IN PLACE ALONG AND AHEAD OF THE SURFACE TROUGH...CENTERED OVER OUR CWA. CINH APPEARS TO BE WEAKENING...HOWEVER ONLY SOME SHALLOW CU HAVE FORMED SO FAR THIS AFTERNOON. AS MID LEVEL VORTICITY ROTATES FROM THE CENTRAL ROCKIES INTO EASTERN COLORADO I WOULD EXPECT DEVELOPMENT TO SPREAD EAST WHICH IS IN LINE WITH SYNOPTIC SCALE GUIDANCE. HRRR/RAP BOTH INDICATE ISOLATED ACTIVITY DEVELOPING ALONG AND EAST OF THE SURFACE TROUGH OVER OUR CWA WITH ADDITIONAL ACTIVITY SPREADING IN FROM THE WEST. BULK SHEER/HELICITY ARE NOT VERY IMPRESSIVE AT THIS POINT WHERE BETTER INSTABILITY IS IN PLACE (WEST). MOISTURE PROFILES ARE NOT PARTICULARLY IMPRESSIVE...AND THIS COULD LIMIT COVERAGE TO ISOLATE/SCATTERED. BETTER PRECIP SIGNAL AND INSTABILITY ARE SHOW IN IN THE LOWER SHEER ENVIRONMENT...WHERE PULSE TYPE THUNDERSTORMS WOULD BE MORE LIKELY. STEEP MID LEVEL LAPSE RATES AND MODERATE INSTABILITY COULD SUPPORT STRONGER UPDRAFTS/CORES...WITH LARGE HAIL/SEVERE WINDS POSSIBLE. DCAPE VALUES 1000-1500 J/KG AND IN HIGHER TD DEPRESSIONS (MAINLY WEST) DO RAISE A CONCERN FOR INCREASED MICROBURST POTENTIAL WITH SOME OF THESE STORMS. IF ANY OF THIS ACTIVITY WAS TO MOVE INTO THE EASTERN CWA IT COULD BECOME MORE ORGANIZED WITH INCREASING SPEED SHEER (35KT BULK EFFECTIVE SHEER AROUND 00Z). AS THE SUN SETS AND WE LOOSE DAYTIME HEATING ANY LINGERING ACTIVITY SHOULD QUICKLY WEAKEN AS THERE IS ELEVATED CAPE LATE AND ONLY A WEAK LLJ IN PLACE OVERNIGHT. SUNDAY...ANOTHER VERY WARM DAY IS EXPECTED AS SURFACE TROUGH DEEPENS A LITTLE OVER THE CWA AND WAA INCREASES OVER THE CWA. THIS IS IN RESPONSE TO A STRONGER SHORTWAVE TROUGH MOVING INTO THE NORTHERN PLAINS AND A COLD FRONT DROPPING SOUTH INTO NORTHERN NEBRASKA. HIGHS SHOULD BE SIMILAR TO TODAY WITH MOST IN THE 80S...AND A FEW LOCATIONS APPROACHING 90 (MAINLY MCCOOK/HILL CITY). SURFACE TROUGH WILL SHIFT JUST A LITTLE BIT EAST AND LOW LEVEL MOISTURE RETURN COULD BRING HIGHER TD VALUES INTO NORTH CENTRAL KS. NAM MAY BE A LITTLE HIGH...BUT EITHER WAY THIS BETTER BL MOISTURE WILL SUPPORT HIGHER CAPE VALUES IN THE AFTERNOON IN THE 2000-2500 J/KG RANGE. SHEER MAY ALSO BE A LITTLE BIT BETTER WHERE GOOD INSTABILITY IS IN PLACE THAN TODAY...SO THERE MAY BE A BIGGER THREAT FOR MORE ORGANIZE THUNDERSTORM DEVELOPMENT IF ANYTHING IS TO DEVELOP IN THE AFTERNOON. THUNDERSTORM ACTIVITY IS SHOWN TO INITIATE PRIMARILY ALONG SURFACE TROUGH IN THE AFTERNOON. HOWEVER WITH DRIER MOISTURE PROFILES AGAIN IN PLACE COVERAGE COULD BE LIMITED AT LEAST UNTIL LATER WHEN BETTER LARGE SCALE FORCING/DEEPER MOISTURE MOVINGS IN TO THE REGION FROM THE NORTHWEST. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 226 AM MDT SAT MAY 2 2015 THE LONG TERM FORECAST PERIODS BEGINS WITH AN UPPER LEVEL SHORTWAVE TROUGH THAT TAKES A NEGATIVE TILT INTO THE HIGH PLAINS REGION...WHICH WILL BRING CHANCES FOR SHOWERS AND THUNDERSTORMS TUESDAY. ALTHOUGH A NEGATIVE TILT USUALLY SIGNIFIES STEEP LAPSE RATES ALOFT...IN THIS CASE THE LAPSE RATES ARE NOT TOO IMPRESSIVE WITH VERY LITTLE CAPE IN THE PROFILE. BETWEEN 200 AND 500 J/KG OF CAPE IS PRESENT ACROSS THE AREA TUESDAY AFTERNOON AND EVENING...BUT THAT IS ENOUGH WITH VERY SATURATED FORECAST SOUNDINGS TO PRODUCE EFFICIENT RAINFALL. STRONG SOUTHERLY FLOW THROUGHOUT THE ENTIRE ATMOSPHERIC PROFILE WILL ADVECT MOIST GULF AIR INTO THE REGION WITH PRECIPITABLE WATER AMOUNTS ACROSS THE AREA GREATER THAN ONE INCH...WHICH IS IN THE 99TH PERCENTILE BASED ON CLIMATOLOGY. THEREFORE...INCREASED POP AND QPF VALUES IN THE FORECAST FOR THIS PERIOD WITH THE EXPECTATION OF WIDESPREAD MODERATE RAINFALL...WITH LOCALLY HEAVY AMOUNTS. IN THE EARLY MORNING HOURS WEDNESDAY...GFS SOUNDINGS INDICATE AN INTRUSION OF DRY MID LEVEL AIR...WHICH WILL INCREASE CAPE VALUES IN THE PROFILE HEADING INTO WEDNESDAY AFTERNOON BETWEEN 1000 AND 1800 J/KG....WHICH COULD RESULT IN SOME STRONGER THUNDERSTORMS. SEVERE POTENTIAL DOES NOT LOOK STRONG AT THIS POINT WITH WEAK SURFACE FORCING...MARGINAL SPEED AND DIRECTIONAL SHEAR...AND DISAGREEMENT IN MODEL FORECASTS REGARDING JET POSITION. ALTHOUGH MODELS DISAGREE SLIGHTLY TO THE UPPER LEVEL TROUGH POSITION...TIMING AND PATTERN GENERALLY LINE UP ON THURSDAY AFTERNOON WITH THE UPPER TROUGH GETTING PINCHED OFF FROM THE MAIN FLOW AND BECOMING CUT OFF OVER THE WESTERN THIRD OF THE CONUS. BECAUSE THE LOW WILL BECOME REMOVED FROM THE MAIN UPPER JET FLOW...THE FEATURE WILL SPIN SLOWLY EASTWARD OVER THE HIGH PLAINS REGION PROVIDING CHANCES FOR SHOWERS AND THUNDERSTORMS THURSDAY NIGHT THROUGH FRIDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1137 AM MDT SAT MAY 2 2015 VFR CONDITIONS AND WINDS LESS THAN 12KT SHOULD PREVAIL AT BOTH KGLD AND KMCK TERMINALS THROUGH THE TAF PERIOD. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING ALONG SURFACE TROUGH THIS AFTERNOON AND EVENING. BETTER COVERAGE SHOULD REMAIN ALONG COLORADO STATE LINE WITH ACTIVITY TRANSITIONING EAST AND SOUTH BASED ON SHORT RANGE GUIDANCE. THIS PLACES ACTIVITY WITHIN THE VICINITY OF KGLD...BUT LIKELY SOUTH OF KMCK. POTENTIAL EXISTS FOR STRONG/SEVERE THUNDERSTORMS WITH HAIL/STRONG WINDS WITH SOME OF THESE STORMS...SO WILL NEED TO AMEND IF IT LOOKS LIKE ANY PARTICULAR STORM WILL IMPACT A TERMINAL. COVERAGE/CONFIDENCE TOO LOW TO INCLUDE MORE THAN VCTS AT KGLD AT THIS TIME. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...MK AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1244 PM CDT Sat May 2 2015 .UPDATE... Issued at 911 AM CDT SAT MAY 2 2015 Updated the forecast to keep a mention of scattered showers over eastern KS into the early afternoon. The RAP has analyzed a weak vort max drifting over the area which can be seen in the 500MB profiler data. Think the HRRR may have a reasonable grasp on the showers through the morning. Also there appears to be little or no instability. Mid level lapse rates are not that steep and models prog little change to them into the early afternoon. With there being little lightning activity now, do not think it will intensify over the next several hours so have removed the mention of thunder from the forecast. UPDATE Issued at 649 AM CDT SAT MAY 2 2015 More light showers are developing across central and south central KS this morning and have upped POPs for southern portions of forecast area this morning because of that. Precip falling from mid-level deck and considerable low-level dry air to overcome, so expect sprinkles to a few hundredths at most with this activity. Short range models weaken this area this morning as it moves east. Otherwise no changes to going forecast. && ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 351 AM CDT SAT MAY 2 2015 Showers/isolated thunderstorms across southeast Nebraska and far northeast KS are occurring in elevated warm advection zone near convergence at nose of low-level jet. This activity has been confined to far northeastern part of forecast area and should remain there this morning. Bigger question what else gets going in central/north central KS in the next few hours and that could move across a far greater portion of northeast KS this morning. Poorly defined shortwave trough seen best in RAP analysis and also somewhat apparent in water vapor loop moving toward north central KS at the current time. HRRR, RAP and 06Z NAM all have a larger area of precip developing in the next few hours apparently associated with this feature. If it develops as forecast, it will affect a wider part of northeast KS this morning than previously thought. Have expanded area of 20-30 percent POPs this morning due to trends in short range models, but difficult to go too high with virtually nothing showing up on radar over central KS at this time. Whatever precip develops should be moving out of far northeast KS early this afternoon and expect dry conditions for the rest of this afternoon through tonight as weak ridging aloft is over the area. Temps today will depend on cloud cover with far eastern KS most likely to see the most persistent clouds and temps only in the upper 70s while some clearing this afternoon in central KS should lead to lower 80s. .LONG TERM...(Sunday through Friday) Issued at 351 AM CDT SAT MAY 2 2015 By Sunday, models show a broad mid-level ridge stretched across the southern CONUS with surface low pressure extending from the High Plains into the Northern Plains. With this low pressure just west of the forecast area, a decent pressure gradient is expected to set up over the area, resulting in breezy southerly winds supporting good warm-air advection across the entire forecast area. With these conditions in place, have continued to trend on the warmer side of model guidance with highs in the low/mid 80s. Models continue to hold off on the front moving into north central Kansas until Sunday evening, so have a dry forecast for the daytime hours with chance to likely PoPs Sunday night through Monday as the cold front advances into the CWA and then stalls out over the area. By Monday the mid-level ridge will be focused across the southeastern U.S. and should start building northward Monday night into Tuesday, causing the stalled cold front to lift northward as a warm front. There are still some model discrepancies with how far north the warm front will lift (near the KS/NE border or into southern NE), but have lowered or even removed PoPs from far east central Kansas Monday night with likely PoPs still near the KS/NE border. The best chance for dry conditions looks to be on Tuesday with the front likely to the north, so have continued to drop PoPs to only slight chances or even dry for some locations. However, shower and thunderstorm chances return Tuesday night as a mid-level trough over the southwestern U.S. lifts northeastward toward the area, strengthening the surface low pressure system and pushing it into the High Plains. Models seem to be coming into slightly better agreement with the tracking of the mid-level trough and surface low, with the trough lifting into the Central Plains Wed/Wed night and into the Northern Plains by Thursday. At the surface, the surface low and associated cold front look to be stalled out along the High Plains Tuesday night through Wednesday before shifting a bit further east. With this steady southerly flow into the region, should see some modest moisture advection into the area by mid- week as we should be able to tap into moisture from the Gulf of Mexico. This moisture advection along with some mid-level forcing will bring increasing chances for scattered showers and thunderstorms Tuesday night through Wednesday night with diminishing chances for the remainder of the week as we lose the mid-level forcing. With low confidence in whether or not scattered precipitation will be lingering by the end of the week, have dropped PoPs to low-end chances for Thursday night and Friday. The persistent southerly flow and moisture advection also will lead to mild conditions with highs in the 70s and lows in the 50s/60s as well as humid conditions with dewpoints steadily in the 50s/60s. && .AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon) Issued at 1224 PM CDT SAT MAY 2 2015 Improving conditions will be the trend for the rest of today outside of the increase in winds. Gusts are likely as clouds dissipate and mixing takes place. Wind shear conditions could be present tomorrow morning with the LLJ increasing over the region, but did leave mention out of the TAFs for now. There is the possibility also for a round of showers or elevated convection late in the TAF period associated with a vorticity max moving out of the Central Rockies affecting all the terminals. Timing on this would be uncertain at this point but will be something to pay attention to for longer term planning. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Wolters SHORT TERM...GDP LONG TERM...Hennecke AVIATION...Drake
AREA FORECAST DISCUSSION
NWS DULUTH MN
325 PM CDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 324 PM CDT SAT MAY 2 2015 A SFC LOW WAS MOVING INTO NW ONTARIO AT 19Z WITH A TRAILING COLD FRONT SWWD INTO WESTERN ND. A SFC TROF WAS ALSO FOUND IN CENTRAL ND. THUNDERSTORMS WERE FIRING AHEAD OF THIS TROF IN THE VCNTY OF EMBEDDED PIECES OF ENERGY IN FAST ZONAL FLOW ALOFT. AN AREA OF SFC FGEN WAS ALSO CO-LOCATED WITH THE STORMS. EXPECT THIS LINE OF STORMS TO REACH NW MN BY 21Z. THE STORMS WILL CONTINUE TO MOVE EWD AND REACH THE NW CORNER OF KOOCHICHING COUNTY BY 01Z. HOWEVER...IT IS AT THIS POINT IN TIME WHEN THE STORMS BEGIN TO ENCOUNTER DRIER AIR THAT HAS BEEN CAMPED OUT OVER THE FORECAST AREA. LATEST SHORT TERM HIRES MODELS INCLUDING THE HRRR AND RAP SHOW THIS TREND AS WELL. AS THIS INITIAL ROUND OF STORMS DISSOLVES...THE NEXT ROUND WILL BEGIN TO DEVELOP OVER THE WESTERN HALF OF THE AREA AROUND 06Z AS THE SFC FRONT MAKES PROGRESS EWD INTO THE REGION. A LOW LEVEL INVERSION SEEN ON AREA FORECAST SOUNDINGS INDICATE THAT THESE STORMS WILL BE ELEVATED IN NATURE. ON SUNDAY...THE FRONT WILL PROGRESS SLOWLY EWD THROUGH THE DAY. SOME WEAK THUNDERSTORMS WILL BE AROUND IN THE MORNING AS A THERMAL RIDGE AXIS IS OVER THE REGION AND INSTABILITY IS WEAK. BY AFTERNOON...THE FRONT PUSHES INTO NW WI WITH MAX HEATING...STORMS WILL BECOME A BIT MORE VIGOROUS...AND BORDER ON SEVERE. SBCAPE INCREASES TO NEAR 3000 J/KG AND LI/S TO -8C PER FORECAST SOUNDINGS. SHOULD SEE SOME STORMS NEAR SEVERE WITH LARGE HAIL AND BRIEF HEAVY RAIN AS PWATS ARE 1 TO 1.25 INCHES. MODELS COME INTO AGREEMENT WITH THIS SOLUTION AND HAVE ROBUST QPF BY 00Z MONDAY. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 324 PM CDT SAT MAY 2 2015 SUNDAY EVENING THE COLD FRONT MOVES SOUTHEAST AWAY FROM THE AREA...AND WHILE I HAVE MAINTAINED SOME POPS FOR THE EVENING HOURS...EXPECT THEY WILL ONLY BE ONGOING AT THE VERY BEGINNING OF THE PERIOD AND EXIT QUICKLY DURING THE EVENING. A COOLER AND DRIER AIRMASS MOVES INTO THE AREA AFTER MIDNIGHT AND WILL LINGER THROUGH MONDAY AND MONDAY NIGHT. LOWS SUNDAY NIGHT AND MONDAY NIGHT TO FALL INTO THE MID 30S TO MID 40S FOR MUCH OF THE AREA...WITH HIGHS MONDAY BACK IN THE 60S TO AROUND 70. THE UPPER LEVEL PATTERN IS EXPECTED TO SHIFT TO A LONGWAVE TROUGH OVER THE WEST COAST AND ROCKIES...WITH WEAK RIDGING TO ZONAL FLOW OVER THE EASTERN CONUS. THIS TROUGHINESS TO OUR WEST IS GOING TO SENT A STRONG...SLOW MOVING UPPER LEVEL LOW SHORTWAVE ACROSS THE UPPER MIDWEST TUESDAY THROUGH FRIDAY...WITH SOME FAIRLY HIGH CHANCES FOR PRECIPITATION DURING THE PERIOD. TEMPERATURES WILL ALSO BE ABOVE NORMAL WITH HIGHS IN THE 70S EVEN WITH INCREASED CLOUD COVER AND PRECIPITATION. THIS SYSTEM TO MOVE OFF TO THE NORTHEAST BY SATURDAY...BUT THE UPPER LEVEL PATTERN OF A TROUGH OUT WEST REMAINS WITH WARM AIR STILL BEING FUNNELED IN OUR DIRECTION AND SOME LINGERING PRECIPITATION CHANCES INTO THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1245 PM CDT SAT MAY 2 2015 A COLD FRONT WILL TRIGGER SHOWERS AND THUNDERSTORMS AS IT TRACKS ACROSS NORTHWEST MINNESOTA THIS EVENING. THERE IS SOME UNCERTAINTY IN TIMING AND WHETHER THE STORMS WILL HOLD TOGETHER AS THEY REACH THE KINL AREA...AND HAVE PUT IN ONLY A PROB30 GROUP AT THIS TIME...WITH NO THUNDER IN ANY OF THE OTHER TAFS...JUST VCSH GROUPS AS THE FRONT MOVES THROUGH. AHEAD OF THE FRONT...WINDS ALOFT AT 1.5-2 KFT INCREASE TO 30-35 KTS FOR 06Z-12Z LATE TONIGHT. HAVE ADDED LLWS FOR KDLH AND KHIB...AND MAY NEED TO ALSO BE ADDED FOR KHYR AS WELL. ADDITIONAL THUNDERSTORM ACTIVITY IS EXPECTED AFTER 18Z SUNDAY...BUT MAINLY FOR KHYR. && .PRELIMINARY POINT TEMPS/POPS... DLH 52 77 44 67 / 10 40 0 0 INL 48 73 38 66 / 10 10 0 0 BRD 54 76 44 70 / 30 30 0 0 HYR 53 77 44 70 / 10 60 20 0 ASX 53 80 44 67 / 10 60 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ010-018-025- 026. WI...NONE. LS...NONE. && $$ SHORT TERM...GSF LONG TERM...LE AVIATION...LE
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1234 PM CDT Sat May 2 2015 .UPDATE... Issued at 907 AM CDT SAT MAY 2 2015 Raised PoPs over most of the CWA to account for ongoing convection over the northwest third of the forecast area as well as the approaching activity now over central KS. The northwest MO activity is associated with moderately strong isentropic ascent on the 300K and 305K surfaces as well as support from a shortwave trough moving east across NE. The KS activity is associated with a weak mid-level vorticity trough and vorticity max. The 12z NAM picks up on the KS vorticity max and even strengthens it as it moves into northwest MO. Not quite buying the strengthening process nor the placement but do expect the feature to persist as it moves east into the CWA. The HRRR model trend maintains a steady flow of scattered showers being generated over southeast NE and moving into northwest MO while the initial activity weakens as it moves into northeast MO. The HRRR also holds onto the KS activity as it crosses into west central MO by 18z as well as continuing east into the central portion of the forecast area. What this all means is a need to increase PoPs and clouds across the CWA and a need to lower temperatures across the northern half of the CWA where PoPs are highest. Will monitor cloud/precipitation trends as there is a good chance we`ll need to lower temperatures further over the west central CWA. One last item is we`ve stripped away thunder from the forecast as the instability is puny and not expected to increase. There may be a stray cg strike in the far northwest near the southern edge of the stronger isentropic ascent and where lightning is occurring over southwest IA. && .DISCUSSION... Issued at 351 AM CDT SAT MAY 2 2015 Today/Tonight: Several subtle upper disturbances will move through the region, aiding in the development of scattered convection. The most probable locations to receive light measurable precipitation will be along and north of the Interstate 70 corridor. The most active period should coincide with the approach of these impulses, with this morning into the early afternoon one round, and another possible overnight. Modest instability will gradually increase from west to east during the day, and therefore a few scattered thunderstorms will be possible this morning into the evening. Temperatures should warm well into the 70s during the afternoon, even with broken cloud cover. Overnight temperatures will remain in the lower 60s to upper 50s in part to increased moisture advection and cloud cover. Sunday/Monday: A large upper trough skirting the US/Canada border will send a cold front approaching the area by Sunday night. This will be the primary focus for the most spatially concentrated area for convection during this period. The front is expected to settle near northwest Missouri on Monday before stalling, and with strong daytime heating, convection is expected to develop over NW MO. Deep layer shear is expected to be rather weak, unless a subtle upper disturbance not yet resolvable can enhance speeds, although moderate instability around MUCAPE 1500 J/kg will develop ahead of the boundary. While severe weather is not likely, a few stronger storms may evolve during the afternoon and evening hours. Tuesday through Saturday: An active pattern looks to evolve across much of the region, albeit severe weather probabilities still appear low/uncertain at this time. A negatively-tilted shortwave trough is projected to lift into the Plains Tuesday into Wednesday. In its wake, continued southwesterly flow will establish over the region, with several embedded upper disturbances expected to move through. While specific details are not resolvable in this period for this particular pattern, it is reasonable to believe several episodes of convection will be possible for portions of the area. Questions regarding an initial meridional wind field and the degree of destabilization limits confidence/signal for severe weather. As for temperatures, above normal readings are expected to continue, with highs in the 70s and 80s. && .AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon) Issued at 1228 PM CDT SAT MAY 2 2015 VFR conditions this afternoon despite thick mid level ceilings around 10k ft and showers. An area of showers with pockets of MVFR ceilings with the heavier showers will slowly shift east across northern MO this afternoon. Activity should gradually weaken. Band of spotty showers over eastern KS will also track east and affect the west central MO terminals through mid afternoon, then clouds thin out. Increasingly southwesterly low level jet will advance east overnight. Expect these winds to reach the ground by mid morning resulting in gusty conditions. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...MJ DISCUSSION...Blair AVIATION...MJ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
343 PM CDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 341 PM CDT SAT MAY 2 2015 ONVECTION CHANCES HEADLINES THE SHORT TERM DISCUSSION. THE BEST CHANCES OF MEASURABLE QPF APPEARS TO COME LATE THIS AFTERNOON/EARLY EVENING...AND THEN AGAIN SUNDAY AFTERNOON. NEAR ZONAL FLOW ALOFT ACROSS THE CENTRAL PLAINS WILL PERSIST THROUGH THE SHORT TERM PERIOD...WITH A BROAD AREA OF HIGH PRESSURE LOCATED OVER THE SOUTH CENTRAL CONUS...AND A TROUGH NOTED NORTH OF THE CANADIAN BORDER...CURRENTLY NEAR ALBERTA. THIS PATTERN IS ALLOWING A LEE SURFACE TROUGH TO DEEPEN AND SLOWLY MOVE EASTWARD FROM THE HIGH PLAINS ONTO THE WESTERN SANDHILLS. AS OF 19Z...A QUICK SUBJECTIVE ANALYSIS OF THE SFC WOULD INDICATE THE TROUGH NOW EAST OF KAIA...LOCATED WEST OF A KOGA TO MRRR1 LINE. CONVECTIVE DEVELOPMENT HAS JUST BEGUN ALONG AND EAST OF THE TROUGH...FROM CENTRAL CHERRY COUNTY SOUTH TO NEAR KIML. THE CU IS WELL IN IT/S INFANCY STAGE...WITH FULL DEVELOPMENT LIKELY TWO 1-2 HOURS /OR MORE/ FROM NOW. DETERMINISTIC AND LATEST HI-RES GUIDANCE CONTINUES TO SHOW GOOD AGREEMENT IN TWO INITIAL AREAS OF TSTORMS...FIRST ACROSS SOUTHWEST NEBRASKA AND THE OTHER FROM CENTRAL CHERRY COUNTY SOUTH INTO THE CENTRAL SANDHILLS...HOWEVER THE LATEST 02/17Z SPC HRRR SUGGESTS A BROKEN LINE EXTENDING ACROSS MUCH OF THE SFC TROUGH...WITH THE LINE ADVANCING EAST WITH TIME. LOWER TROPOSPHERIC MOISTURE IS NOW DECREASING WITH THE INCREASED AFTERNOON MIXING...WITH MOST LOCATIONS TD/S NOW BELOW 10C. SO...NOT COMPLETELY BUYING INTO THE NOTION OF THE EXTENDED BROKEN LINE OF TSTORMS...BUT ISOLATED CONVECTION IS STILL ANTICIPATED. WILL CARRY ISO-SCT POPS EAST OF THE SFC TROUGH THROUGH THE FA THIS EVENING. LLJ DOES RAMP UP SLIGHTLY OVERNIGHT...MAY POSSIBLY SEE A LINGERING STORM ACROSS OUR EAST BEYOND 06Z...OR ADDITIONAL WEAK CONVECTION DEVELOP ELSEWHERE...BUT CHANCES WILL BE MINUSCULE AFTER 06Z TONIGHT. IN TERMS OF SEVERE...LATEST THERMO PARAMETERS INDICATE UPWARDS TO 1500-2000 J/KG OF MLCAPE...HOWEVER SHEAR IS MARGINAL WHERE TOWERS ARE CURRENTLY GOING UP...SO WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED THIS AFTERNOON OR EVENING...BUT A FEW STRONG/LOW-END SVR STORMS MAY PRODUCE HAIL OR ESPECIALLY GUSTY WIND AS SOUNDINGS REVEAL A INCREASING INVERTED-V PROFILE. SUNDAY...A COLD FRONT AND/OR SFC TROUGH WILL PROVIDE FOR A CHANCE OF ADDITIONAL STORM DEVELOPMENT DURING THE AFTERNOON HOURS...BUT THE BETTER FOCUS FOR WIDESPREAD STORMS APPEARS TO REMAIN EAST AND SOUTH OF THE FORECAST AREA. BY 21Z...STEEP LAPSE RATES WILL CONTRIBUTE TO UPWARDS OF 1000-1500 J/KG CAPE ACROSS NORTH CENTRAL NEBRASKA WITH FAVORABLE SHEAR FOR SOME DEVELOPMENT...THUS WILL MAINTAIN ISOLATED TO SCATTERED CHANCES OF STORMS ACROSS NORTH CENTRAL NEBRASKA DURING THE AFTERNOON HOURS. BETTER MOISTURE IN THE LOWER TROPOSPHERE WOULD ALLOW FOR SOME RAIN PRODUCING STORMS IN THIS AREA. ONCE AGAIN HOWEVER...WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 341 PM CDT SAT MAY 2 2015 UNSETTLED PERIOD AHEAD AS A LARGE LONG WAVE TROUGH WILL BE ESTABLISHED ACROSS THE WESTERN PORTION OF THE UNITED STATES THROUGH MUCH OF THE COMING WEEK. RAIN CHANCES LOOK GOOD FOR MUCH OF THE CENTRAL PLAINS AS A RESULT...WITH AT LEAST SOME CHANCE OF A FEW SCATTERED SEVERE THUNDERSTORMS. A COLD FRONT WILL SETTLE ACROSS NORTHERN KANSAS MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO BE ONGOING ACROSS A GOOD PORTION OF WESTERN AND NORTH CENTRAL NEBRASKA MONDAY MORNING...AIDED BY A COMBINATION OF A SOUTHERLY LOW LEVEL JET NOSING INTO THE AREA AND A SHORTWAVE ALOFT EJECTING NORTHEAST ACROSS THE REGION. MAY BE A BIT OF A LULL IN THE PRECIPITATION MONDAY AFTERNOON AND MONDAY EVENING...BUT CANNOT COMPLETELY RULE OUT AT LEAST SOME SCATTERED SHOWERS/T-STORMS...ESPECIALLY AGAIN MONDAY NIGHT AS THE H850MB FRONT IS ANCHORED ALONG THE NEBRASKA KANSAS BORDER AND THE SOUTHERLY LOW LEVEL JET STRENGTHENS ONCE AGAIN. TUESDAY INTO WEDNESDAY APPEARS TO BE THE BEST CHANCE FOR PRECIPITATION. A STRONG SHORTWAVE WILL EJECT NORTHEAST FROM THE LONG WAVE TROUGH DURING THIS TIME. GOOD MODEL AND ENSEMBLE AGREEMENT THAT THIS WILL BE NEGATIVELY TILTED AS IT EMERGES ONTO THE PLAINS. HAVE INCREASED CHANCES FOR RAIN A FURTHER TUESDAY INTO WEDNESDAY...AS STRONG MOISTURE TRANSPORT AND STRONG LIFT SHOULD ENSURE RAIN. SOME INSTABILITY IN THE MID LEVELS...SO WILL KEEP THE THUNDER MENTION GOING. CERTAINLY COULD BE SOME STRONG OR PERHAPS EVEN A SEVERE STORM OR TWO DURING THIS TIMEFRAME...BUT MAY VERY WELL BE SOCKED IN WITH LOW CLOUDS DUE TO SUCH STRONG MOISTURE ADVECTION...AND THIS WOULD CUT DOWN ON SURFACE BASED INSTABILITY AND OTHERWISE MORE ROBUST SEVERE WEATHER THREAT. WILL CONTINUE TO MONITOR THIS PERIOD CLOSELY. ABOVE MENTIONED SHORTWAVE MOVES NORTHEAST AWAY FROM THE AREA THURSDAY...AND HAVE TRIED TO REFLECT THIS WITH ONLY SLIGHT OR LOW CHANCE POPS. THEN THE MAIN LONG WAVE TROUGH WILL EJECT EAST INTO THE CENTRAL AND NORTHERN PLAINS THURSDAY NIGHT THOUGH SATURDAY. AGAIN APPEARS A NEGATIVE TILT WITH THIS SYSTEM...WHICH WILL QUICKLY HELP PULL MOISTURE BACK INTO THE WESTERN HIGH PLAINS. MORE RAIN LIKELY AS THIS OCCURS INTO THE FIRST OF THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1249 PM CDT SAT MAY 2 2015 THUNDERSTORM CHANCES HEADLINE THE AVIATION DISCUSSION...WITH TWO POSSIBLE...ALBEIT SLIGHT...CHANCES OF STORMS IMPACTING PORTIONS OF THE SANDHILLS REGION. THE FIRST CHANCE COMES LATE AFTERNOON AND INTO THE EVENING HOURS TONIGHT WHEN A SFC TROUGH ADVANCES EAST ACROSS THE SANDHILLS. THE 02.12Z NAM AND LATEST HRRR SEEM TO BE A GOOD COMPROMISE IN THAT STORMS SHOULD FORM ACROSS THE HEART OF THE SANDHILLS AND POSSIBLY ACROSS SW NEBRASKA. THE SECOND CHANCE COMES LATE IN THE FORECAST PERIOD SUNDAY MORNING...WHERE NORTH CENTRAL NEBRASKA IS FAVORED FOR STORM DEVELOPMENT. BOTH INSTANCES STORMS WILL BE ISOLATED TO SCATTERED AT BEST...SO CONFIDENCE IN STORMS IMPACTING EITHER KVTN OR KLBF IS LOW...MAY NEED UPDATES. IF A STORM DOES IMPACT A TERMINAL...GUSTY ERRATIC WIND AND SMALL HAIL WOULD BE POSSIBLE. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JACOBS LONG TERM...TAYLOR AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1249 PM CDT SAT MAY 2 2015 .UPDATE... ISSUED AT 700 AM CDT SAT MAY 2 2015 PRECIPITATION ENDING OVER NORTH CENTRAL NEBRASKA EARLY THIS MORNING. SOME PATCHY FOG ALONG THE PLATTE RIVER VALLEY. SINCE IT IS SO LOCALIZED HAVE LEFT OUT OF THE FORECAST AND WILL COVER WITH NOWCASTS. UPDATED WEATHER...WINDS AND SKY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 322 AM CDT SAT MAY 2 2015 MODELS HAVE GOOD RUN TO RUN CONSISTENCY IN THE NEAR TERM AND HAVE GOOD CONFIDENCE IN THE FORECAST. FIRST CONCERN IS WHETHER TO INCLUDE PRECIP IN THE FORECAST THIS MORNING. THUNDERSTORMS INTO SOUTH CENTRAL CHERRY COUNTY, STORMS ARE MOVING TO THE EAST SOUTHEAST AROUND 20KTS AND THIS SHOULD HAVE MOST ACTIVITY CLEARING FORECAST AREA BY 1230Z. WILL CARRY A PRE FIRST PERIOD. TEMPERATURES AND PRECIPITATION THIS AFTERNOON AND THIS EVENING WILL BE MAIN FORECAST CHALLENGE. STILL 59F AT 1 AM CDT AT KLBF. CLEARING SKIES THIS MORNING AND LIGHT NORTH WINDS ON THE BACKSIDE OF WEAK DISTURBANCE WILL DROP TEMPERATURES TO AROUND 50F OVER MOST OF THE FORECAST AREA. VERY WARM START TO THE DAY. STRONG SOUTHERLY FLOW BEGINNING OVER NORTHWEST NEBRASKA AND EXPANDING EAST THROUGH WESTERN NEBRASKA THROUGH THE DAY. HEATING OF THE DAY TD`S IN THE LOW 50S AND WEAK FORCING IN THE AFTERNOON ALONG THE SURFACE TROUGH WITH SOME MARGINAL MUCAPE WILL BRING THE CHANCE FOR ISOLATED THUNDERSTORMS AGAIN ALONG THE TROUGH AXIS AND THEN SHIFTING EAST THROUGH THE DAY AND EARLY EVENING. WEAK LLJ WILL DEVELOP TO THE THE SOUTHWEST AND CARRY AND ENHANCE TRW AS THEY MOVE EAST. LLJ NOT AS STRONG 20 TO 25 KTS. DYNAMICS WILL DIMINISH THROUGH 6Z AND HAVE ENDED CHANCES AFTER THEN. LOWS AGAIN AROUND 50. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 322 AM CDT SAT MAY 2 2015 THE LONG TERM PERIOD IS FILLED WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS AS A LONGWAVE TROUGH SETS UP OVER THE WESTERN CONUS. THE UPPER AIR PATTERN SUNDAY MORNING WILL BE HIGHLIGHTED BY A STRONG LOW OFF THE PAC NW COAST...AND A WEAKER LOW TO THE SOUTH OVER THE NORTHERN BAJA. THE SPLIT FLOW PHASES OVER THE CENTRAL CONUS AS A LOW AMPLITUDE BEGINS TO SET UP OVER THE EASTERN HALF OF THE CONUS. THE POSITION OF THE HIGH PRESSURE WILL OPEN UP THE GULF OF MEXICO EARLY NEXT WEEK AS MEAN SOUTHERLY LOW LEVEL FLOW DEVELOPS FROM THE YUCATAN PENINSULA NORTHWARD UP THE PLAINS. A COLD FRONT WILL SLOWLY MOVE OVER THE CWA SUNDAY...STRETCHING FROM SOUTHWEST TO NORTH CENTRAL NEBRASKA BY LATE AFTERNOON. THIS WILL LIKELY SERVE AS THE FOCUS FOR ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT AS RICHER THETA-E AIR POOLS IN THE VICINITY OF THE SFC FRONTAL AXIS. STEEPENING MID LEVEL LAPSE RATES WILL SUPPORT A FEW STRONG TO MARGINALLY SEVERE STORMS...HOWEVER THE OVERALL SEVERE THREAT SHOULD BE LOW OWING TO A LACK OF QUALITY MOISTURE DEPTH...MEAGER DEEP LAYER SHEAR...AND WEAK UPPER LEVEL SUPPORT. THE FRONT STALLS OUT OVER KANSAS ON MONDAY AND EASTERLY UPSLOPE FLOW SETS UP OVER THE CWA. THIS WILL LEAD TO THE DEVELOPMENT OF WIDESPREAD CLOUDINESS...COOLER TEMPS...AND CONTINUED CHANCES FOR SHOWERS AND STORMS. THE GFS...EC...AND THEIR RESPECTIVE ENSEMBLES ARE IN FAIRLY GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER LEVEL PATTERN IN THE TUESDAY-WEDNESDAY TIMEFRAME. THE SOUTHERN STREAM PV EJECTS OUT OF THE DESERT SOUTHWEST TOWARD THE CENTRAL PLAINS. HEIGHT RISES OCCUR DOWNSTREAM AS THE UPPER LEVEL FLOW BECOMES NEARLY MERIDIONAL OVER THE CENTRAL CONUS. CROSS SECTIONS SHOW STRONG THETA-E ADVECTION IN THE LOW TO MID LEVELS WITH IMPRESSIVE MOISTURE TRANSPORT INTO WESTERN NEBRASKA. GFS PUSHES PWATS INTO THE 2+ STANDARD DEVIATIONS ABOVE CLIMO RANGE FOR NORTH PLATTE. WIDESPREAD SHOWERS AND STORMS APPEAR LIKELY AT THIS TIME...AS WELL AS A POSSIBILITY FOR LOCALIZED HEAVY RAINFALL. THE SEVERE THREAT TUESDAY AND WEDNESDAY IS TOUGH TO DISCERN AS THE WIDESPREAD AND PERSISTENT QPF CURRENTLY SHOWN IN THE MODELS WOULD LIKELY LIMIT THE DEGREE OF DESTABILIZATION. MODELS MAINTAIN DECENT AGREEMENT WITH THEIR HANDLING OF SYNOPTIC FEATURES TOWARD THE LATTER HALF OF NEXT WEEK. THE UPPER LEVEL LOW OVER THE PAC NW SLOWLY DROPS SOUTHEAST INTO THE CENTRAL ROCKIES WITH BROAD ANTICYCLONIC FLOW HOLDING STRONG OVER THE EASTERN CONUS. THIS WILL KEEP CONDITIONS FAVORABLE FOR MORE UNSETTLED WEATHER OVER THE CENTRAL PLAINS INCLUDING THE POTENTIAL FOR SEVERE WEATHER LATE IN THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1249 PM CDT SAT MAY 2 2015 THUNDERSTORM CHANCES HEADLINE THE AVIATION DISCUSSION...WITH TWO POSSIBLE...ALBEIT SLIGHT...CHANCES OF STORMS IMPACTING PORTIONS OF THE SANDHILLS REGION. THE FIRST CHANCE COMES LATE AFTERNOON AND INTO THE EVENING HOURS TONIGHT WHEN A SFC TROUGH ADVANCES EAST ACROSS THE SANDHILLS. THE 02.12Z NAM AND LATEST HRRR SEEM TO BE A GOOD COMPROMISE IN THAT STORMS SHOULD FORM ACROSS THE HEART OF THE SANDHILLS AND POSSIBLY ACROSS SW NEBRASKA. THE SECOND CHANCE COMES LATE IN THE FORECAST PERIOD SUNDAY MORNING...WHERE NORTH CENTRAL NEBRASKA IS FAVORED FOR STORM DEVELOPMENT. BOTH INSTANCES STORMS WILL BE ISOLATED TO SCATTERED AT BEST...SO CONFIDENCE IN STORMS IMPACTING EITHER KVTN OR KLBF IS LOW...MAY NEED UPDATES. IF A STORM DOES IMPACT A TERMINAL...GUSTY ERRATIC WIND AND SMALL HAIL WOULD BE POSSIBLE. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...POWER SHORT TERM...POWER LONG TERM...MARTIN AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
135 PM EDT SAT MAY 2 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND INTO MUCH OF THE EARLY WEEK. OUR NEXT BEST CHANCE OF PRECIPITATION WILL COME DURING THE MIDDLE OF NEXT WEEK WHEN A BACKDOOR COLD FRONT APPROACHES OUR AREA. && .NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM EDT SATURDAY... OVERALL A NICE DAY TO START OFF THE WEEKEND. THE DENSE FOG ADVISORY EXPIRED AT 9AM. THERE ARE STILL SOME ISOLATED POCKETS OF RIVER VALLEY FOG ACROSS THE MOUNTAIN EMPIRE...HOWEVER THAT SHOULD BURN OFF WITHIN THE NEXT HOUR OR SO. MOST OF THE REGION CAN EXPECT A DRY AND PARTLY SUNNY DAY...ALTHOUGH THERE IS THE SLIGHT CHANCE FOR AN ISOLATED SHOWER FOR A BRIEF WINDOW THIS AFTERNOON EAST OF THE BLUE RIDGE. HRRR CONTINUES TO SHOW WEAK INSTABILITY OF 100-300 MU CAPE EARLY THIS AFTERNOON AND WANTS TO POP UP A FEW SHOWERS...THEREFORE ADDED SLIGHT CHANCE POPS OUT EAST. AS OF 730 AM EDT SATURDAY... DENSE FOG ADVISORY FOR A FEW COUNTIES IN THE NORTH EXPIRES AT 13Z. SURFACE AND UPPER LOW WILL CONTINUE TO MOVE FURTHER OUT INTO THE ATLANTIC OCEAN TODAY WITH HIGH PRESSURE AND DRIER AIR OVER THE OHIO VALLEY BUILDING EASTWARD. TODAY WILL BE PARTLY TO MOSTLY SUNNY AND MILDER WITH HIGHS ACROSS THE MOUNTAINS RANGING FROM THE MID 60S TO NEAR 70 DEGREES...WITH LOW TO MID 70S ACROSS THE PIEDMONT. CONTINUED DRY AND TRANQUIL OVERNIGHT WITH LOWS NEAR SEASONAL NORMALS IN THE 40S. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 PM EDT FRIDAY... WEAK HIGH PRESSURE WILL SLIDE ACROSS THE REGION SUNDAY. AS THIS HIGH MOVES TO THE COAST...LIGHT SOUTHERLY FLOW WILL BRING WARM MOIST AIR INTO THE REGION. WITH SOME WEAKNESS ALOFT FROM AN UPPER LEVEL TROUGH...ISOLATED SHOWERS ARE POSSIBLE OVER THE NORTH CAROLINA HIGH COUNTRY LATE SUNDAY AFTERNOON. ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE MONDAY AFTERNOON AS A COOL POOL ALOFT DRIFTS OVER THE REGION. TEMPERATURES WILL RUN WARMER THAN NORMAL SUNDAY AND MONDAY WITH AREAS SEEING SHOWERS PEAKING IN THE UPPER 60S AND LOCATIONS REMAIN DRY WARMING INTO THE 70S. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 125 PM EDT FRIDAY... LONG WAVE PATTERN ADVERTISED BY MODELS SHOWED TROFING IN THE WESTERN UNITED STATES AND A BROAD SOUTHEAST U.S. RIDGE. A SURFACE COLD FRONT THE THE NORTHERN STREAM WILL BE OVER THE GREAT LAKES ON MONDAY AND WILL PUSH SOUTH AS A BACKDOOR FRONT OVER THE MID ATLANTIC REGION TUESDAY AND WEDNESDAY. QUESTIONABLE HOW FAR SOUTH THIS BOUNDARY GETS HEADING INTO A LARGE RIDGE OVER THE SOUTHEAST. BEST PROBABILITY OF PRECIPITATION WILL BE IN THE VICINITY OF THIS BOUNDARY. OTHERWISE THE CHANCE WILL BE LIMITED TO AIRMASS TYPE THUNDERSTORMS...MAINLY IN THE MOUNTAINS EACH AFTERNOON AND EVENING. MAXIMUM/MINIMUM TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE NORMAL TUESDAY THROUGH FRIDAY. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 130 PM EDT SATURDAY... HIGH PRESSURE WAS OVER THE TENNESSEE VALLEY THIS AFTERNOON. SATELLITE PICTURES SHOWED SCATTERED TO BROKEN VFR CUMULUS...MAINLY EAST OF THE BLUE RIDGE. CLOUD COVER WILL DIMINISH THIS EVENING ONCE THE SUN SETS. WINDS WILL BECOME LIGHT AND VARIABLE TONIGHT AS HIGH PRESSURE CROSSES THE AREA. EXPECT DEW POINTS ARE LOW ENOUGH TO LIMIT FORMATION OF FOG OVERNIGHT. THE MOST LIKELY LOCATION THAT MAY SEE SHALLOW GROUND FOG IS KLWB BUT CONFIDENCE WAS NOT HIGH ENOUGH TO ADD TO THE TAF AT THIS TIME. NOTE...THE VISIBILITY SENSOR AT THE ASOS AT KBLF CONTINUES TO BE OUT OF SERVICE. REPAIRS MAY NOT BE POSSIBLE UNTIL THE END OF MAY. WILL CONTINUE WITH AMD NOT SKED APPENDED TO THIS TAF. EXTENDED AVIATION DISCUSSION... OTHER THAN SOME PATCHY LATE NIGHT/EARLY MORNING RIVER VALLEY FOG IN THE TYPICAL LOCATIONS...VFR CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. SCATTERED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THE SOUTHERN BLUE RIDGE ON TUESDAY...WHICH WOULD YIELD MVFR CONDITIONS. SHOWERS AND THUNDERSTORMS WILL BE MORE WIDESPREAD ON WEDNESDAY AND THURSDAY AS A BACK DOOR FRONT ENTERS THE REGION. HIGH PRESSURE ALOFT WILL LIMIT MUCH IN THE WAY OF ANY SYNOPTIC-SCALE FORCING THROUGH THE PERIOD. && .EQUIPMENT... AS OF 130 PM EDT SATURDAY... THE VISIBILITY SENSOR AT THE BLUEFIELD...KBLF...ASOS MAY ALTERNATE BETWEEN AVAILABLE AND UNAVAILABLE UNTIL FURTHER NOTICE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...CF/PC SHORT TERM...RCS LONG TERM...AMS AVIATION...AMS/PC EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
341 PM CDT SAT MAY 2 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 341 PM CDT SAT MAY 2 2015 FORECAST FOCUS IS ON SMALL RAIN CHANCES TONIGHT...AND BETTER RISK FOR SHOWERS AND STRONG THUNDERSTORMS ON SUNDAY. WEAK SHORT WAVE TROUGH MOVING THROUGH IA THIS AFTERNOON WITH A FEW SHOWERS AND ISOLATED THUNDERSTORMS OCCURRING. MODELS HAVING SOME ISSUES WITH HOW TO HANDLE THIS FEATURE. DISTURBANCE IS MOVING DUE EAST AND SHOULD CONTINUE TO DO SO THIS EVENING. SOME MODELS INSIST ON NEW DEVELOPMENT OVERNIGHT IN THE DEFORMATION AREA ON THE BACK SIDE OF THE WAVE...LIKELY AS THE LOW LEVEL JET ENHANCES MOISTURE TRANSPORT INTO THE REGION. BUT NOT SOLD ON THAT HAPPENING. HAVE MAINTAINED A LOW CHANCE OVER OUR FAR SOUTHERN AREA BUT OTHERWISE LEAVING THE FORECAST DRY TONIGHT. OF LARGER CONCERN IS THE COLD FRONT MOVING THROUGH THE AREA SUNDAY AFTERNOON AND EVENING. A POTENT SHORT WAVE TROUGH WILL PASS INTO FAR NORTHERN MN LATE SUNDAY...HELPING SUPPORT THE FRONT AS IT DROPS SOUTHWARD. FRONTAL PASSAGE IN THE MOST OPPORTUNE TIME OF DAY...AND AMPLE MOISTURE LOOKS TO BE AVAILABLE AS SOUTHERLY WINDS CONTINUE TO ENHANCE TRANSPORT AHEAD OF THE BOUNDARY. MODEL CAPE FORECAST SUGGESTS AS MUCH AS 2500-3000 J/KG...BUT THIS LIKELY OVERDONE AS MODEL DEWPOINTS APPEAR TO BE INFLATED A BUT. BUT SUFFICE TO SAY THERE WILL BE ENOUGH INSTABILITY TO SUPPORT STRONG UPDRAFTS. BETTER SHEAR LOOKS TO LAG BEHIND THE FRONT...BUT ENOUGH PRESENT FOR STRONG STORMS...ESPECIALLY GIVEN THE COLD AIR MOVING IN BEHIND. HAIL AND STRONG WIND ARE A POSSIBILITY AND SPC INCLUDES OUR AREA IN THE DAY 2 SLIGHT RISK. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 341 PM CDT SAT MAY 2 2015 FRONT CONTINUES SOUTH THROUGH THE AREA EARLY MONDAY...BUT THEN STALLS OUT. BOUNDARY LOOKS TO LINGER AROUND THE GENERAL AREA ALL THE WAY INTO WEDNESDAY. WITH THIS BOUNDARY SERVING AS A FOCAL POINT...COULD SEE PERIODIC SHOWERS AND ISOLATED THUNDERSTORMS INTO MID WEEK. MEDIUM RANGE MODELS THEN IN GOOD AGREEMENT THAT A SIGNIFICANT SHORT WAVE TROUGH WILL EJECT NORTHEAST UP AND ACROSS OUR REGION OUT OF THE MEAN WEST COAST LONG WAVE TROUGH. THIS WILL PASS LATE WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A COUPLE OF PERIODS OF SHOWERS AND THUNDERSTORMS. YET ANOTHER SIGNIFICANT SYSTEM LOOKS TO MOVE IN FOR NEXT WEEKEND...SO A PERIOD OF ACTIVE WEATHER LOOKS TO BE IN THE OFFING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 102 PM CDT SAT MAY 2 2015 A SHORT WAVE TROUGH MOVING THROUGH THE MID MISSISSIPPI RIVER VALLEY IS PRODUCING A 7-12K BROKEN DECK OF CLOUDS SOUTH OF INTERSTATE 90. THE HRRR SUGGESTS THAT SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP IN THIS AREA AROUND 03.20Z. MEANWHILE THE RAP KEEPS THE AREA DRY. AT THIS TIME...LEANING MORE TOWARD THE RAP. THESE CLOUDS WILL MOVE EAST OF THE AREA BY 03.06Z. BOTH TAF SITES ARE ON THE NORTHERN EDGE...SO JUST MENTIONED A SCATTERED 7 TO 8K DECK. IN ADDITION TO THE CLOUDS...THE SOUTH WINDS WILL GUST INTO THE 20 TO 25 KNOT RANGE THROUGH 03.01Z. ON SUNDAY MORNING...A BROKEN 25K DECK OF CLOUDS WILL MOVE INTO THE AREA AHEAD OF AN APPROACHING COLD FRONT. WITH DIURNAL MIXING... THE WINDS WILL START TO GUST INTO THE 20 TO 25 KNOT RANGE AFTER 03.14Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...MW LONG TERM...MW AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
103 PM CDT SAT MAY 2 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 314 AM CDT SAT MAY 2 2015 WATER VAPOR SATELLITE IMAGERY THIS MORNING MAKES SOME SUGGESTION OF A WEAK SHORT WAVE TROUGH OVER EASTERN WYOMING. THIS IS THE FEATURE THE 02.00Z MODELS INDICATE WILL PASS ACROSS IOWA THIS AFTERNOON AND EVENING. THIS WAVE WILL ONLY BE ABLE TO PRODUCE SOME VERY WEAK PV ADVECTION IN THE 500-300 MB LAYER. HOWEVER...AS IT COMES ACROSS THE 02.00Z NAM SUGGEST THE LOW LEVEL RETURN FLOW WILL INCREASE DURING THE AFTERNOON AHEAD OF IT WITH SOME WEAK MOISTURE TRANSPORT INTO THE AREA AT 850 MB FOR LATE THIS AFTERNOON INTO THE EVENING. SOME ISENTROPIC UP GLIDE ON THE ORDER OF 1 TO 2 UBAR/S WILL DEVELOP AS WELL DURING THE LATE AFTERNOON AND THEN INCREASE TO 2 TO 4 UBAR/S OVERNIGHT ON THE 300K SURFACE. THE MOISTURE TRANSPORT ON THIS LAYER COULD ALSO INCREASE OVERNIGHT INTO THE AREA. THESE FEATURES COULD BE ENOUGH TO GENERATE A FEW SHOWERS AND STORMS SIMILAR TO WHAT THE NAM AND 02.00Z HI-RES NMM SHOW. WILL CONTINUE TO HAVE SOME RAIN CHANCES UP TO ABOUT 20 PERCENT FOR MOST OF THE AREA TONIGHT...BUT IF THE HI-RES MODELS ARE CORRECT...THE ACTIVITY COULD BE CONFINED TO THE IOWA/MINNESOTA BORDER AND SOUTH. THE FOCUS THEN TURNS TO THE SYSTEM COMING IN FOR SUNDAY AND SUNDAY NIGHT. THE SHORT WAVE TROUGH CURRENTLY OVER SOUTHERN BRITISH COLUMBIA WILL AMPLIFY AS IT MOVES EAST BUT FOR THE MOST PART REMAINS SOMEWHAT POSITIVELY TILTED AS IT MOVES ACROSS SOUTHERN CANADA AND THE EXTREME NORTHERN PORTIONS OF THE U.S. THE MODELS HAVE ALSO BEEN CONSISTENT IN TRYING TO SHOW SOME SECONDARY SHORT WAVE TROUGHS COMING ACROSS THE UPPER MIDWEST AHEAD OF THE MAIN SHORT WAVE TROUGH...WHETHER THESE BREAK OFF FROM THE MAIN TROUGH OR ARE GENERATED BY CONVECTION...IS DIFFERENT FROM MODEL TO MODEL. NONE OF THE MODELS REALLY GENERATE ANY PV ADVECTION OVER THE AREA WITH THE 02.00Z ECMWF THE FARTHEST SOUTH BRINGING SOME WEAK PV ADVECTION ACROSS NORTHERN WISCONSIN SUNDAY NIGHT. IF THIS IS TRUE...IS WILL LEAVE THE LOW LEVEL FORCING ALONG THE FRONT AS THE MAIN DRIVER FOR THE DEVELOPMENT OF THE CONVECTION. THE FRONTOGENESIS ALONG THE FRONT LOOKS TO MAINLY BE IN THE 1000-700 MB LAYER AND SHOULD BE WEAK TO MODERATE IN STRENGTH. THE ISENTROPIC UP GLIDE ON THE 305K SURFACE LOOKS LIKE IT SHOULD BE IN THE 3-5 UBAR/S RANGE. MOST OF THE MOISTURE TRANSPORT STILL LOOKS TO BE THROUGH THE AREA TERMINATING NORTH OF THE AREA WITH THE MAIN SHORT WAVE TROUGH. WITH THESE FORCING SIGNALS...HAVE SOME CONCERNS ABOUT HOW MUCH CONVECTION WILL ACTUALLY FORM ALONG THE FRONT. GRANTED...IT IS RIGHT AT THE END OF THE HI-RES MODEL RUNS...BUT THE ARW AND NMM BOTH ONLY SHOW A BROKEN AND NARROW LINE OF CONVECTION ALONG THE FRONT BY 00Z MONDAY. THESE MODELS ALSO SHOW THIS ONLY GETTING INTO THE FAR NORTHWESTERN SECTIONS OF THE FORECAST AREA LATE SUNDAY AFTERNOON. THE STORMS THAT DO DEVELOP STILL LOOK TO HAVE SOME POTENTIAL TO PRODUCE SEVERE WEATHER WITH DAMAGING WINDS AND LARGE HAIL THE MAIN THREATS. AN AXIS OF 1500 J/KG OF ML CAPE SHOULD BE IN PLACE AHEAD OF THE FRONT FOR SUNDAY AFTERNOON INTO THE EARLY EVENING. THE BEST SHEAR WILL BE CONFINED TO THE 0-3 KM LAYER BUT MAY BE ONLY ABOUT 25 KNOTS AHEAD OF THE FRONT WITH THE NAM AND GFS SHOWING THE BEST SHEAR REMAINING BEHIND THE FRONT. THE FRONT AND CONVECTION SHOULD MOVE THROUGH PRETTY QUICKLY SUNDAY NIGHT WITH THE ACTIVITY CONFINED TO THE SOUTHEAST HALF OR SO OF THE AREA AFTER 06Z MONDAY. THE FRONT THEN LOOKS TO BECOME STATIONARY SOUTH OF THE AREA FOR MONDAY. THERE WILL BE ACTIVITY ALONG AND NORTH OF THE FRONT AND THE CONCERN IS JUST HOW FAR NORTH THIS WILL EXTENT. THE NAM AND ECMWF WOULD SUGGEST IT WOULD STAY SOUTH OF THE AREA WHILE THE GFS BRINGS IT INTO THE SOUTHERN SECTIONS OF THE AREA. IF THE FRONT DOES MAKE IT INTO NORTHERN MISSOURI BEFORE STALLING OUT...WHICH IS THE MODEL CONSENSUS...FEEL THE NAM AND ECMWF HAVE A BETTER CHANCE OF BEING CORRECT AND WILL ONLY SHOW A SMALL CHANCE ACROSS THE SOUTH TO HONOR THE GFS. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 314 AM CDT SAT MAY 2 2015 ONCE THE SHORT WAVE TROUGH FROM SUNDAY NIGHT MOVES PAST THE AREA...THE FLOW IS STILL EXPECTED TO BECOME SOUTHWEST WITH A LARGE UPPER LEVEL LOW OFF THE PACIFIC NORTHWEST COAST AND ANOTHER LOW OVER THE SOUTHWEST. AS THE LOW OFF THE NORTHWEST COAST MOVES INLAND AND THE UPPER LEVEL RIDGE AMPLIFIES OVER THE SOUTHEAST CONUS...IT WILL FORCE THE SOUTHWEST SYSTEM TO MOVE NORTHEAST TOWARD THE REGION THROUGH THE PERIOD. IT DOES NOT LOOK LIKE THIS WILL COME THROUGH AS ONE PIECE OF ENERGY BUT ACTUALLY GET STRUNG OUT AND ACT AS SEVERAL SHORT WAVE TROUGHS. THE FRONT THAT STALLS SOUTH OF THE AREA WILL GET DRAWN BACK NORTH TUESDAY AND TUESDAY NIGHT AND SHOULD BE NORTH OF THE AREA BY WEDNESDAY NIGHT. A COLD FRONT WILL THEN START TO APPROACH FROM THE WEST THURSDAY AND MOVE INTO THE AREA FRIDAY. WITH THIS PATTERN...WILL HAVE TO CARRY RAIN CHANCES FOR EACH PERIOD BUT DOUBTFUL THERE WILL ACTUALLY BE THAT MUCH RAIN AROUND. COULD SEE SOME POTENTIAL FOR A DRY PERIOD OR TWO ONCE THE FRONT MOVES NORTH OF THE AREA...BUT CONFIDENCE IS NOT HIGH ENOUGH TO TRY AND INCORPORATE THAT INTO THE FORECAST AT THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 102 PM CDT SAT MAY 2 2015 A SHORT WAVE TROUGH MOVING THROUGH THE MID MISSISSIPPI RIVER VALLEY IS PRODUCING A 7-12K BROKEN DECK OF CLOUDS SOUTH OF INTERSTATE 90. THE HRRR SUGGESTS THAT SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP IN THIS AREA AROUND 03.20Z. MEANWHILE THE RAP KEEPS THE AREA DRY. AT THIS TIME...LEANING MORE TOWARD THE RAP. THESE CLOUDS WILL MOVE EAST OF THE AREA BY 03.06Z. BOTH TAF SITES ARE ON THE NORTHERN EDGE...SO JUST MENTIONED A SCATTERED 7 TO 8K DECK. IN ADDITION TO THE CLOUDS...THE SOUTH WINDS WILL GUST INTO THE 20 TO 25 KNOT RANGE THROUGH 03.01Z. ON SUNDAY MORNING...A BROKEN 25K DECK OF CLOUDS WILL MOVE INTO THE AREA AHEAD OF AN APPROACHING COLD FRONT. WITH DIURNAL MIXING... THE WINDS WILL START TO GUST INTO THE 20 TO 25 KNOT RANGE AFTER 03.14Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...BOYNE