Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/21/16
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
931 AM MDT TUE APR 19 2016
.UPDATE...
ISSUED AT 916 AM MDT TUE APR 19 2016
MAIN UPPER LEVEL LOW HAS REFORMED JUST EAST OF DENVER WITH RAIN
AND SNOW SHOWERS ACROSS THE NERN PLAINS. THE UPPER LEVEL LOW IS
SUPPOSED TO MOVE INTO THE FAR NERN CORNER BY LATE AFTN. ALONG AND
EAST OF THE LOW THERE WILL CONTINUE TO BE A THREAT FOR ADDITIONAL
SHOWERS THIS AFTN. MEANWHILE WITH ABUNDANT MOISTURE AND FAVORABLE
LAPSE RATES THIS AFTN SHOULD SEE SOME ADDITIONAL DEVELOPMENT
FURTHER WEST OF THE LOW AS WELL. RAP KEEPS THIS ACTIVITY FOCUSED
ALONG AND NEAR THE NRN FOOTHILLS WHILE THE HRRR KEEPS THE ACTIVITY
EAST OF THE FOOTHILLS FROM DENVER NORTH TO THE WYOMING BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM MDT TUE APR 19 2016
FORECAST UPDATES BEING MADE AS UPPER LEVEL DISTURBANCE IS SPINNING
OUT A BIT FARTHER NORTH THAN ANTICIPATED. AS A RESULT...SNOW WAS
SPREADING NORTH EARLY THIS MORNING INTO THE DENVER METRO AREA AND
I-76 CORRIDOR ON THE PLAINS. A COUPLE EMBEDDED WAVES WERE NOTED IN
THE DISTURBANCE...ONE ROTATING QUICKLY NORTHEAST ACROSS THE PALMER
DIVIDE WITH DEFORMATION SNOWFALL ON THE NORTHERN PERIPHERY
SPREADING NORTH. ANOTHER WAVE WAS HANGING BACK A BIT OVER WESTERN
PARK COUNTY. THIS WILL LIKELY KEEP THE LIGHT SNOW GOING THROUGH AT
LEAST MID MORNING BEFORE TAPERING OFF. SOME RAIN IN THE LOWER
ELEVATIONS...MAINLY BELOW 4500-5000 FEET BUT ENOUGH COOLING DUE TO
DRY AIR AND WET BULB EFFECTS COULD BE A BIT LOWER. AREAS THAT SEE
SNOW THIS MORNING COULD SEE AROUND AN INCH OF ACCUMULATION.
BY LATER THIS MORNING INTO THE AFTERNOON...PRECIPITATION WILL BE
SHIFTING EASTWARD ACROSS THE PLAINS. MESOSCALE MODELS SHOW SOME
CONVECTIVE POTENTIAL AND SEEMS REASONABLE GIVEN INCREASING LAPSE
RATES UNDER THE COLD POOL. THREAT OF ANY THUNDER WOULD BE LIMITED
HOWEVER BY RATHER WIDESPREAD CLOUD DECK WITH SHORT WAVE. WILL
TREND FORECAST WORDING FROM STRATIFORM IN THE MORNING TO SHOWERS
IN THE AFTERNOON. LOCATIONS CLOSER TO THE FRONT RANGE MAY DRY OUT
COMPLETELY THIS AFTERNOON WITH WEAK DOWNSLOPE COMPONENT
DEVELOPING...BUT ITS UNSTABLE ENOUGH FOR A FEW SHOWERS TO STILL
DRIFT OFF THE ELEVATED TERRAIN. SPEAKING OF WHICH...THE MOUNTAINS
ARE EXPECTED TO SEE CONVECTIVE SHOWERS BECOME MORE NUMEROUS
THROUGH LATE AFTERNOON AND EVENING AS ANOTHER WEAK WAVE ROTATING
AROUND THE MAIN UPPER LOW REACHES THE NORTHERN MOUNTAINS. AT THIS
TIME EXPECTING ANOTHER 2 TO 5 INCHES FOR MOST OF THE MOUNTAINS
ABOVE 9000 FEET FOR THIS AFTERNOON THROUGH TONIGHT. PLAINS HAVE
JUST A SLIGHT CHANCE OF A SHOWER OR TWO LINGERING PAST MIDNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 355 AM MDT TUE APR 19 2016
DRIER AND WARMER WEATHER WILL MAKE A RETURN FOR THE LATTER HALF OF
THE WEEK AS AN UPPER RIDGE TAKES A COUPLE DAYS TO DEVELOP OVER THE
STATE. IT LOOKS LIKE SATURDAY WILL BE THE PINNACLE OF THE WARMING
TREND. BEFORE THAT...TEMPERATURES WILL REACH TO THE 50S
WEDNESDAY...60S ON THURSDAY AND THEN AROUND THE 70 DEGREE MARK
FRIDAY AFTERNOON. TEMPERATURES ON SATURDAY SHOULD PEAK IN THE MID
TO UPPER 70S. ON WEDNESDAY...THE UPPER LEVEL CIRCULATION SLOWLY
MOVING OUT OF THE REGION WILL DELIVER ONE FINAL ROUND OF SHOWERS
AS CYCLONIC NORTHWESTERLY FLOW COVERS NORTHEAST COLORADO. MOUNTAIN
AREAS COULD SEE SOME SNOW SHOWERS IN THE MORNING...MIXING IN A FEW
THUNDERSTORMS IN THE AFTERNOON. RAIN SHOWERS WILL ALSO COVER THE
NORTHEAST CORNER OF THE PLAINS WHICH ALSO TRANSITION TO
THUNDERSTORMS IN THE AFTERNOON. MUCH DRIER CONDITIONS WILL THEN
PREVAIL THROUGH THE END OF THE WEEK.
AFTER THE WARM DAYS ON FRIDAY AND SATURDAY...THINGS BEGIN TO COOL
BACK DOWN ON SUNDAY AND MONDAY AS LONG RANGE MODELS SHOW
TROUGHINESS AND MOIST SOUTHWEST FLOW ALOFT ACROSS THE STATE. THE
GFS AND CANADIAN MODELS SHOW THE TROUGH DEEPER THAN THE ECMWF
SOLUTION...SO WILL LEAN TOWARDS THOSE TWO MODELS FOR NOW. THE
APPROACH OF THE TROUGHINESS WILL BRING A RETURN OF SHOWERS...FIRST
IN THE MOUNTAINS AND EVENTUALLY OUT ONTO THE PLAINS DURING THE
FIRST PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 916 AM MDT TUE APR 19 2016
WINDS ARE FCST TO GRADUALLY SHIFT TO MORE ELY BY 18Z AND CONTINUE
THRU THE AFTN. MAIN CONCERN FOR THIS AFTN WILL BE IF ADDITIONAL
SHOWERS DVLP. RAP KEEPS SHOWER DEVELOPMENT IN AND NEAR THE
FOOTHILLS WHILE THE HRRR HAS ACTIVITY REDEVELOPING OVER DIA BY
EARLY AFTN. AT THIS TIME NOT SURE WHICH WAY TO GO SO WILL JUST
MENTION VCNTY FOR THIS AFTN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RPK
SHORT TERM...BARJENBRUCH
LONG TERM...DANKERS
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
ISSUED BY NATIONAL WEATHER SERVICE TAUNTON MA
142 PM EDT TUE APR 19 2016
.SYNOPSIS...
HIGH PRESSURE BUILDS IN TONIGHT AND WEDNESDAY. THE HIGH MOVES OFF
THE COAST THURSDAY. A COLD FRONT WILL SLOWLY WORK ITS WAY THROUGH
THE REGION LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT. HIGH
PRESSURE RETURNS FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
130 PM UPDATE...
NO SIGNIFICANT CHANGES TO FORECAST. CLOUDS HEADING SOUTH OF
NORTHERN CT HAVE INDEED MOSTLY DISSIPATED BY THE TIME OF REACHING
THE CT COAST. BRIEFLY CLOUDED UP IN NEW LONDON COUNTY BUT SHOULD
BECOME MOSTLY SUNNY BY 2 PM. TEMPERATURES EXPECTED TO MAX OUT IN
MID 60S ACROSS MUCH OF SOUTHERN CT...LONG ISLAND AND HUDSON VALLEY
OUTSIDE OF THE METRO AREA. TEMPS SHOULD CONTINUE TO HOVER IN LOWER
70S ACROSS METRO AREA AND ADJACENT NJ.
RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM. COULD SEE SMOKE
FROM FIRE IN MEADOWLANDS ON KOKX RADAR. SMOKE PLUME WAS HEADING SE
TOWARD OPEN WATER.
1115 AM UPDATE...
HAVE MADE ONLY MINOR ADJUSTMENTS TO PRIOR FORECAST TO KEEP
TEMPS...WINDS...SKY COVER AND DEWPOINTS IN LINE WITH CURRENT
OBSERVATIONS/TRENDS. UPPED THE WINDS JUST A BIT AND NOW DEPICT
GUSTS GENERALLY BETWEEN 25 AND 30 MPH FOR THE AFTERNOON. DEWPOINTS
WERE RUNNING HIGHER THAN FORECAST BUT SHOULD DROP RATHER RAPIDLY
AS DEEP VERTICAL MIXING WILL BE TAKING PLACE. THERE IS A SIZABLE
PATCH OF STRATOCUMULUS CLOUDS MOVING SOUTH ACROSS CONNECTICUT BUT
EXPECT PARTIAL DISSIPATION WITH THE AID OF DOWNSLOPING.
NEVERTHELESS...NEEDED TO PUT SOME ADDITIONAL CLOUDS INTO THE CT
AND LONG ISLAND ZONES THROUGH EARLY AFTERNOON.
WIND GUSTS COMBINED WITH LOW RELATIVE HUMIDITIES RESULTING IN
CONTINUATION OF RED FLAG WARNING AS POSTED.
VIGOROUS SHORTWAVE/PVA DIVES OUT OF CANADA FROM AROUND HUDSON
BAY VICINITY ACROSS THE NORTHEAST TODAY...WITH LOWERING HEIGHTS
NOTED. SFC FRONT MOVES THROUGH THIS MORNING...WITH MODELS
INDICATING AREA OF LOW PRESSURE PASSING ACROSS EASTERN LOCALES
THIS MORNING BEFORE TRACKING SOUTHEAST OVER THE WESTERN ATLANTIC
LATE TODAY.
A PASSING SHOWER OR SPRINKLE IS POSSIBLE...ESPECIALLY ACROSS
SOUTHERN NEW ENGLAND/SE CT ZONES. HRRR CONTINUES TO BE THE MOST
AGGRESSIVE WITH ANY SHOWER ACTIVITY WITH HIGHER COVERAGE THAN MOST
OF THE NWP MODEL SUITE THROUGH ABOUT 14Z OR SO.
WINDS SHIFT TO THE NW/N THIS MORNING...AND GUSTS 20 TO 25 MPH ARE
EXPECTED. AFTER MORNING CLOUDS WITH THE FRONT AND ASSOCIATED
TROUGH...CLEARING TAKES PLACE FROM MID TO LATE MORNING AND
THROUGH THE AFTERNOON.
COLDER AIR LAGS A BIT...AND EXPECT TEMPS TO REMAIN QUITE
MILD...ALTHOUGH NOT AS WARM AS YESTERDAY. DEW POINTS LIKELY FALL
LOWER THAN MOS FCST OUTPUT...A TYPICAL OCCURRENCE IN THIS TYPE OF
PATTERN. FEEL DRY EARLY SPRING AIR WILL MIX DOWN RESULTING IN
LOWER DEW POINTS BY MID TO LATE AFTERNOON. THE DRY CONDITIONS
ALONG WITH GUSTY WINDS WARRANT RED FLAG WARNING FOR TODAY AFTER
COLLAB WITH SURROUNDING OFFICES.
SEE FIRE WEATHER SECTIONS FOR RAPID BRUSH FIRE SPREAD CONCERNS.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
DURING THIS TIME FRAME...TROUGH PIVOTS EAST WITH RIDGE BUILDING
BACK IN...ALTHOUGH RIDGE AXIS REMAINS WELL TO THE WEST THROUGH
WEDNESDAY. SFC HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE
GREAT LAKES REGION TONIGHT...THEN OVER OUR AREA BY AFTERNOON
WEDNESDAY.
CAA AND A TIGHT PRESSURE GRADIENT WILL RESULT IN SOME WIND
TONIGHT. WITH AMPLE BOUNDARY LAYER MIXING...RADIATIONAL COOLING
IS NOT EXPECTED TO BE IDEAL. AS SUCH...PATCHY FROST IS
POSSIBLE...BUT DO NOT ANTICIPATE MUCH FROST DEVELOPMENT TONIGHT
ACROSS THE INTERIOR AND PINE BARRENS OF EASTERN LONG ISLAND.
PLENTY OF SUNSHINE IS FORECAST WEDNESDAY ALONG WITH SEASONABLY
MILD TEMPS. LATE DAY SEA BREEZES ARE LIKELY AS THE PRESSURE
GRADIENT RELAXES WITH THE APPROACH OF HIGH PRESSURE.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
WITH CLEAR SKIES AND DIMINISHING WINDS WED NIGHT...OPTIMAL
RADIATIONAL COOLING CONDS EXPECTED...WITH TEMPS DROPPING INTO THE
30S ACROSS MOST OF THE INTERIOR...COASTAL SE CT AND EASTERN LONG
ISLAND...WHERE WIDESPREAD FROST MAY BE POSSIBLE. LOWS ELSEWHERE
SHOULD RANGE FROM THE MID/UPPER 40S INVOF NYC...TO THE LOWER
40S ELSEWHERE.
THE CENTER OF THE HIGH MOVES OFFSHORE ON THURSDAY...AND THE
RESULTING SW FLOW WILL USHER A WARM AND MILD AIR MASS INTO THE
REGION FOR THE END OF THE WORK WEEK.
HIGHS ON WILL BE IN THE LOWER/MID 60S ON THU...THEN IN THE LOWER/MID
70S FOR MOST AREAS ON FRI.
MEANWHILE...LOW PRES MOVING THROUGH THE GREAT LAKES WILL DRAG A COLD
FRONT EAST. DUE TO THE OFFSHORE HIGH...IT WILL TAKE SOME TIME FOR
THE FRONT TO ACTUALLY MAKE IT HERE. HAVE HELD OFF ON CHANCE POP
UNTIL LATE EVENING THU INTO FRI...THEN DRY FRI NIGHT...BUT THE 00Z
ECMWF HAS SLOWED UP EVEN MORE THAN ITS 18/12 PREDECESSOR...WITH
LITTLE IF ANY PRECIP THU NIGHT...THEN CHANCES FOR PRECIP POSSIBLY
LINGERING INTO AT LEAST FRI EVENING. SEVERAL CONVECTIVE PARAMETERS
ALSO SUGGEST POTENTIAL FOR ISOLD/SCT LATE DAY THUNDER FROM NYC
NORTH/WEST.
HIGH PRES THEN BUILDS IN BEHIND THE DEPARTING FRONT FOR THE WEEKEND.
TEMPS WILL GENERALLY RUN AT OR SLIGHTLY ABOVE NORMAL LEVELS.
ANOTHER WEAK FRONTAL SYSTEM MAY IMPACT THE REGION FOR THE START OF
THE NEW WORK WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE AFTERNOON. BKN CIGS FAR SE
CT WILL BECOME SCT BY 19Z. MAINLY N OR NNW WINDS WITH GUSTS TO
AROUND 25 KT UNTIL 22Z OR 23Z...THEN DIMINISHING. OCCASIONAL
GUSTS AT THE NYC TERMINALS...LONG ISLAND TERMINALS AND SOUTHERN CT
TERMINALS APPROACHING 30 KT AT TIMES THIS AFTERNOON. WIND
DIMINISHES OVERNIGHT...ALTHOUGH A FEW GUSTS TO AROUND OR JUST
ABOVE 20 KT MAY PERSIST THIS EVENING TO MIDNIGHT. VFR CONDITIONS
WITH NO CIG OR VSBY LIMITATIONS EXPECTED ON WED.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: ADJUSTED WINDS TO BE MORE FROM N.
KLGA FCSTER COMMENTS: ADJUSTED WINDS TO BE MORE FROM N.
KEWR FCSTER COMMENTS: SMOKE LAYER NE OF FIELD NOT ANTICIPATED TO
MOVE OVER FIELD.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE BRIEFLY HIGHER THAN
FORECAST.
KHPN FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE BRIEFLY HIGHER THAN
FORECAST.
KISP FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE BRIEFLY HIGHER THAN
FORECAST.
.OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
.WEDNESDAY...VFR.
.THURSDAY...VFR. SW GUSTS 20-25KT.
.LATE THURSDAY NIGHT AND FRIDAY...MVFR POSSIBLE IN SCT SHRA.
SLIGHT CHANCE OF TSRA FRI.
.SATURDAY...VFR.
&&
.MARINE...
NEARSHORE N/NW WINDS WILL BE STRONGER...BUT MOST OF THE OPEN
WATERS AWAY FROM LAND SHOULD REMAIN LIGHTER. THESE WINDS MAY
INCREASE BRIEFLY TO SCA CRITERIA LATE TONIGHT INTO EARLY WEDNESDAY
AS LOW PRESSURE PASSES WELL TO THE EAST AND HIGH PRESSURE BUILDS
TO THE NW. AS COOLER AIR MOVES IN...BETTER CHANCE FOR GUSTS ON THE
WATERS LATE TONIGHT. NOT ENOUGH CONFIDENCE THOUGH FOR ANY SCA
ISSUANCE AT THIS TIME.
SEAS GENERALLY REMAINS UNDER 5 FEET THROUGH WEDNESDAY. THE OUTER
PORTIONS OF THE OCEAN WATERS MAY APPROACH 5 FEET BRIEFLY LATE
TONIGHT INTO EARLY WEDNESDAY.
QUIET ON ALL WATERS WED NIGHT INTO THU NIGHT. THERE IS A CHANCE FOR
MARGINAL SCA CONDS ON THE OCEAN WATERS SOME TIME FRI INTO FRI NIGHT
AS A COLD FRONT MOVES SLOWLY ACROSS. TRANQUIL CONDS RETURN BY THE
WEEKEND AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.HYDROLOGY...
NO SIGNIFICANT RAINFALL THROUGH THURSDAY. A COLD FRONT MOVING
THROUGH FROM THU NIGHT INTO FRI NIGHT MAY BRING 1/10 TO 1/4 INCH
BASIN AVG QPF...WITH POTENTIAL FOR LOCALLY UP TO 1/2 INCH WITH
ANY LATE DAY TSTMS. NO FLOODING ISSUES ANTICIPATED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR CTZ005>012.
NY...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR NYZ067>075-
078>081-176>179.
NJ...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR NJZ002-004-
006-103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...THOMPSON
NEAR TERM...THOMPSON
SHORT TERM...OKX STAFF
LONG TERM...OKX STAFF
AVIATION...THOMPSON
MARINE...THOMPSON/OKX STAFF
HYDROLOGY...OKX STAFF
AREA FORECAST DISCUSSION
NWS NEW YORK NY
720 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT PASSES THROUGH THIS MORNING. HIGH PRESSURE BUILDS IN
TONIGHT AND WEDNESDAY. THE HIGH MOVES OFF THE COAST THURSDAY. A
COLD FRONT WILL SLOWLY WORK ITS WAY THROUGH THE REGION LATE
THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT. HIGH PRESSURE RETURNS
FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VIGOROUS SHORTWAVE/PVA DIVES OUT OF CANADA FROM AROUND HUDSON
BAY VICINITY ACROSS THE NORTHEAST TODAY...WITH LOWERING HEIGHTS
NOTED. SFC FRONT MOVES THROUGH THIS MORNING...WITH MODELS
INDICATING AREA OF LOW PRESSURE PASSING ACROSS EASTERN LOCALES
THIS MORNING BEFORE TRACKING SOUTHEAST OVER THE WESTERN ATLANTIC
LATE TODAY.
A PASSING SHOWER OR SPRINKLE IS POSSIBLE...ESPECIALLY ACROSS
SOUTHERN NEW ENGLAND/SE CT ZONES. HRRR CONTINUES TO BE THE MOST
AGGRESSIVE WITH ANY SHOWER ACTIVITY WITH HIGHER COVERAGE THAN MOST
OF THE NWP MODEL SUITE THROUGH ABOUT 14Z OR SO.
WINDS SHIFT TO THE NW/N THIS MORNING...AND GUSTS 20 TO 25 MPH ARE
EXPECTED. AFTER MORNING CLOUDS WITH THE FRONT AND ASSOCIATED
TROUGH...CLEARING TAKES PLACE FROM MID TO LATE MORNING AND
THROUGH THE AFTERNOON.
COLDER AIR LAGS A BIT...AND EXPECT TEMPS TO REMAIN QUITE
MILD...ALTHOUGH NOT AS WARM AS YESTERDAY. DEW POINTS LIKELY FALL
LOWER THAN MOS FCST OUTPUT...A TYPICAL OCCURRENCE IN THIS TYPE OF
PATTERN. FEEL DRY EARLY SPRING AIR WILL MIX DOWN RESULTING IN
LOWER DEW POINTS BY MID TO LATE AFTERNOON. THE DRY CONDITIONS
ALONG WITH GUSTY WINDS WARRANT RED FLAG WARNING FOR TODAY AFTER
COLLAB WITH SURROUNDING OFFICES.
SEE FIRE WEATHER SECTIONS FOR RAPID BRUSH FIRE SPREAD CONCERNS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
DURING THIS TIME FRAME...TROUGH PIVOTS EAST WITH RIDGE BUILDING
BACK IN...ALTHOUGH RIDGE AXIS REMAINS WELL TO THE WEST THROUGH
WEDNESDAY. SFC HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE
GREAT LAKES REGION TONIGHT...THEN OVER OUR AREA BY AFTERNOON
WEDNESDAY.
CAA AND A TIGHT PRESSURE GRADIENT WILL RESULT IN SOME WIND
TONIGHT. WITH AMPLE BOUNDARY LAYER MIXING...RADIATIONAL COOLING
IS NOT EXPECTED TO BE IDEAL. AS SUCH...PATCHY FROST IS
POSSIBLE...BUT DO NOT ANTICIPATE MUCH FROST DEVELOPMENT TONIGHT
ACROSS THE INTERIOR AND PINE BARRENS OF EASTERN LONG ISLAND.
PLENTY OF SUNSHINE IS FORECAST WEDNESDAY ALONG WITH SEASONABLY
MILD TEMPS. LATE DAY SEA BREEZES ARE LIKELY AS THE PRESSURE
GRADIENT RELAXES WITH THE APPROACH OF HIGH PRESSURE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WITH CLEAR SKIES AND DIMINISHING WINDS WED NIGHT...OPTIMAL
RADIATIONAL COOLING CONDS EXPECTED...WITH TEMPS DROPPING INTO THE
30S ACROSS MOST OF THE INTERIOR...COASTAL SE CT AND EASTERN LONG
ISLAND...WHERE WIDESPREAD FROST MAY BE POSSIBLE. LOWS ELSEWHERE
SHOULD RANGE FROM THE MID/UPPER 40S INVOF NYC...TO THE LOWER
40S ELSEWHERE.
THE CENTER OF THE HIGH MOVES OFFSHORE ON THURSDAY...AND THE
RESULTING SW FLOW WILL USHER A WARM AND MILD AIR MASS INTO THE
REGION FOR THE END OF THE WORK WEEK.
HIGHS ON WILL BE IN THE LOWER/MID 60S ON THU...THEN IN THE LOWER/MID
70S FOR MOST AREAS ON FRI.
MEANWHILE...LOW PRES MOVING THROUGH THE GREAT LAKES WILL DRAG A COLD
FRONT EAST. DUE TO THE OFFSHORE HIGH...IT WILL TAKE SOME TIME FOR
THE FRONT TO ACTUALLY MAKE IT HERE. HAVE HELD OFF ON CHANCE POP
UNTIL LATE EVENING THU INTO FRI...THEN DRY FRI NIGHT...BUT THE 00Z
ECMWF HAS SLOWED UP EVEN MORE THAN ITS 18/12 PREDECESSOR...WITH
LITTLE IF ANY PRECIP THU NIGHT...THEN CHANCES FOR PRECIP POSSIBLY
LINGERING INTO AT LEAST FRI EVENING. SEVERAL CONVECTIVE PARAMETERS
ALSO SUGGEST POTENTIAL FOR ISOLD/SCT LATE DAY THUNDER FROM NYC
NORTH/WEST.
HIGH PRES THEN BUILDS IN BEHIND THE DEPARTING FRONT FOR THE WEEKEND.
TEMPS WILL GENERALLY RUN AT OR SLIGHTLY ABOVE NORMAL LEVELS.
ANOTHER WEAK FRONTAL SYSTEM MAY IMPACT THE REGION FOR THE START OF
THE NEW WORK WEEK.
&&
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL MOVE ACROSS THE AREA TERMINALS THIS MORNING. A
WAVE OF LOW PRESSURE ASSOCIATED WITH THE FRONT WILL ALSO PASS
ACROSS THE REGION.
THE FRONT WILL COME THROUGH MOSTLY DRY...HOWEVER A FEW LIGHT SHOWERS
WILL BE POSSIBLE EAST OF NYC. HIGH PRESSURE BUILDS BACK INTO THE
REGION THROUGH THE DAY TODAY.
LIGHT SOUTHWEST TO WEST WINDS AHEAD OF THE LOW AND COLD FRONT WILL
SHIFT TO THE NORTHWEST TO NORTH BEHIND THE FRONT...AND QUICKLY
INCREASE AND BECOME GUSTY AFTER 13Z-14Z. GUSTS TO AROUND 25 KT
ARE LIKELY WITH OCCASIONAL GUSTS AT THE NYC TERMINALS APPROACHING
30 KT DURING THE AFTERNOON. THE WIND GUSTS CONTINUE
OVERNIGHT...BUT LOWER IN SPEED JUST A BIT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KLGA FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KEWR FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KHPN FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KISP FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
.OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
.WEDNESDAY...VFR.
.THURSDAY...VFR. SW GUSTS 20-25KT.
.LATE THURSDAY NIGHT AND FRIDAY...MVFR POSSIBLE WITH A CHANCE
OF SHOWERS IN SHRA.
.SATURDAY...VFR.
&&
.MARINE...
A COLD FRONT MOVES THROUGH THIS MORNING...AND WINDS WILL SHIFT
AROUND TO THE NW/NW. NEARSHORE WINDS WILL BE STRONGER...BUT MOST
OF THE OPEN WATERS AWAY FROM LAND SHOULD REMAIN LIGHTER. THESE
WINDS MAY INCREASE BRIEFLY TO SCA CRITERIA LATE TONIGHT INTO EARLY
WEDNESDAY AS LOW PRESSURE PASSES WELL TO THE EAST AND HIGH
PRESSURE BUILDS TO THE NW. AS COOLER AIR MOVES IN...BETTER CHANCE
FOR GUSTS ON THE WATERS LATE TONIGHT. NOT ENOUGH CONFIDENCE THOUGH
FOR ANY SCA ISSUANCE AT THIS TIME.
SEAS GENERALLY REMAINS UNDER 5 FEET THROUGH WEDNESDAY. THE OUTER
PORTIONS OF THE OCEAN WATERS MAY APPROACH 5 FEET BRIEFLY LATE
TONIGHT INTO EARLY WEDNESDAY.
QUIET ON ALL WATERS WED NIGHT INTO THU NIGHT. THERE IS A CHANCE FOR
MARGINAL SCA CONDS ON THE OCEAN WATERS SOME TIME FRI INTO FRI NIGHT
AS A COLD FRONT MOVES SLOWLY ACROSS. TRANQUIL CONDS RETURN BY THE
WEEKEND AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.FIRE WEATHER...
A RED FLAG WARNING HAS BEEN ISSUED FOR THIS AFTERNOON AND INTO THE
EARLY EVENING DUE TO VERY DRY FUELS...MIN RH 25-30 PERCENT AND
WINDS GUSTS 20 TO 25 MPH.
DRY CONDITIONS ARE EXPECTED ONCE AGAIN ON WEDNESDAY AS RH VALUES
FALL INTO THE 20S DURING THE DAY. NORTH WINDS WILL RANGE FROM
5-10 MPH...AND WILL GIVE WAY TO COASTAL SEA BREEZES IN THE
AFTERNOON.
&&
.HYDROLOGY...
NO SIGNIFICANT RAINFALL THROUGH THURSDAY. A COLD FRONT MOVING
THROUGH FROM THU NIGHT INTO FRI NIGHT MAY BRING 1/10 TO 1/4 INCH
BASIN AVG QPF...WITH POTENTIAL FOR LOCALLY UP TO 1/2 INCH WITH
ANY LATE DAY TSTMS. NO FLOODING ISSUES ANTICIPATED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
CTZ005>012.
NY...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
NYZ067>075-078>081-176>179.
NJ...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...GOODMAN/PW
NEAR TERM...PW
SHORT TERM...PW
LONG TERM...GOODMAN
AVIATION...BC
MARINE...GOODMAN/PW
FIRE WEATHER...
HYDROLOGY...GOODMAN/PW
AREA FORECAST DISCUSSION
NWS NEW YORK NY
408 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT PASSES THROUGH THIS MORNING. HIGH PRESSURE BUILDS IN
TONIGHT AND WEDNESDAY. THE HIGH MOVES OFF THE COAST THURSDAY. A
COLD FRONT WILL SLOWLY WORK ITS WAY THROUGH THE REGION LATE
THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT. HIGH PRESSURE RETURNS
FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VIGOROUS SHORTWAVE/PVA DIVES OUT OF CANADA FROM AROUND HUDSON
BAY VICINITY ACROSS THE NORTHEAST TODAY...WITH LOWERING HEIGHTS
NOTED. SFC FRONT MOVES THROUGH THIS MORNING...WITH MODELS
INDICATING AREA OF LOW PRESSURE PASSING ACROSS EASTERN LOCALES
THIS MORNING BEFORE TRACKING SOUTHEAST OVER THE WESTERN ATLANTIC
LATE TODAY.
A PASSING SHOWER OR SPRINKLE IS POSSIBLE...ESPECIALLY ACROSS
SOUTHERN NEW ENGLAND/SE CT ZONES. HRRR CONTINUES TO BE THE MOST
AGGRESSIVE WITH ANY SHOWER ACTIVITY WITH HIGHER COVERAGE THAN MOST
OF THE NWP MODEL SUITE THROUGH ABOUT 14Z OR SO.
WINDS SHIFT TO THE NW/N THIS MORNING...AND GUSTS 20 TO 25 MPH ARE
EXPECTED. AFTER MORNING CLOUDS WITH THE FRONT AND ASSOCIATED
TROUGH...CLEARING TAKES PLACE FROM MID TO LATE MORNING AND
THROUGH THE AFTERNOON.
COLDER AIR LAGS A BIT...AND EXPECT TEMPS TO REMAIN QUITE
MILD...ALTHOUGH NOT AS WARM AS YESTERDAY. DEW POINTS LIKELY FALL
LOWER THAN MOS FCST OUTPUT...A TYPICAL OCCURRENCE IN THIS TYPE OF
PATTERN. FEEL DRY EARLY SPRING AIR WILL MIX DOWN RESULTING IN
LOWER DEW POINTS BY MID TO LATE AFTERNOON. THE DRY CONDITIONS
ALONG WITH GUSTY WINDS WARRANT RED FLAG WARNING FOR TODAY AFTER
COLLAB WITH SURROUNDING OFFICES.
SEE FIRE WEATHER SECTIONS FOR RAPID BRUSH FIRE SPREAD CONCERNS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
DURING THIS TIME FRAME...TROUGH PIVOTS EAST WITH RIDGE BUILDING
BACK IN...ALTHOUGH RIDGE AXIS REMAINS WELL TO THE WEST THROUGH
WEDNESDAY. SFC HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE
GREAT LAKES REGION TONIGHT...THEN OVER OUR AREA BY AFTERNOON
WEDNESDAY.
CAA AND A TIGHT PRESSURE GRADIENT WILL RESULT IN SOME WIND
TONIGHT. WITH AMPLE BOUNDARY LAYER MIXING...RADIATIONAL COOLING
IS NOT EXPECTED TO BE IDEAL. AS SUCH...PATCHY FROST IS
POSSIBLE...BUT DO NOT ANTICIPATE MUCH FROST DEVELOPMENT TONIGHT
ACROSS THE INTERIOR AND PINE BARRENS OF EASTERN LONG ISLAND.
PLENTY OF SUNSHINE IS FORECAST WEDNESDAY ALONG WITH SEASONABLY
MILD TEMPS. LATE DAY SEA BREEZES ARE LIKELY AS THE PRESSURE
GRADIENT RELAXES WITH THE APPROACH OF HIGH PRESSURE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WITH CLEAR SKIES AND DIMINISHING WINDS WED NIGHT...OPTIMAL
RADIATIONAL COOLING CONDS EXPECTED...WITH TEMPS DROPPING INTO THE
30S ACROSS MOST OF THE INTERIOR...COASTAL SE CT AND EASTERN LONG
ISLAND...WHERE WIDESPREAD FROST MAY BE POSSIBLE. LOWS ELSEWHERE
SHOULD RANGE FROM THE MID/UPPER 40S INVOF NYC...TO THE LOWER
40S ELSEWHERE.
THE CENTER OF THE HIGH MOVES OFFSHORE ON THURSDAY...AND THE
RESULTING SW FLOW WILL USHER A WARM AND MILD AIR MASS INTO THE
REGION FOR THE END OF THE WORK WEEK.
HIGHS ON WILL BE IN THE LOWER/MID 60S ON THU...THEN IN THE LOWER/MID
70S FOR MOST AREAS ON FRI.
MEANWHILE...LOW PRES MOVING THROUGH THE GREAT LAKES WILL DRAG A COLD
FRONT EAST. DUE TO THE OFFSHORE HIGH...IT WILL TAKE SOME TIME FOR
THE FRONT TO ACTUALLY MAKE IT HERE. HAVE HELD OFF ON CHANCE POP
UNTIL LATE EVENING THU INTO FRI...THEN DRY FRI NIGHT...BUT THE 00Z
ECMWF HAS SLOWED UP EVEN MORE THAN ITS 18/12 PREDECESSOR...WITH
LITTLE IF ANY PRECIP THU NIGHT...THEN CHANCES FOR PRECIP POSSIBLY
LINGERING INTO AT LEAST FRI EVENING. SEVERAL CONVECTIVE PARAMETERS
ALSO SUGGEST POTENTIAL FOR ISOLD/SCT LATE DAY THUNDER FROM NYC
NORTH/WEST.
HIGH PRES THEN BUILDS IN BEHIND THE DEPARTING FRONT FOR THE WEEKEND.
TEMPS WILL GENERALLY RUN AT OR SLIGHTLY ABOVE NORMAL LEVELS.
ANOTHER WEAK FRONTAL SYSTEM MAY IMPACT THE REGION FOR THE START OF
THE NEW WORK WEEK.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL MOVE ACROSS THE AREA TERMINALS THROUGH 12Z. A WAVE
OF LOW PRESSURE ASSOCIATED WITH THE FRONT WILL ALSO PASS ACROSS THE
REGION.
THE FRONT WILL COME THROUGH MOSTLY DRY...HOWEVER A FEW LIGHT SHOWERS
WILL BE POSSIBLE EAST OF NYC. HIGH PRESSURE BUILDS BACK INTO THE
REGION THROUGH THE DAY TODAY.
LIGHT SOUTHWEST TO WEST WINDS AHEAD OF THE LOW AND COLD FRONT WILL
SHIFT TO THE NORTHWEST TO NORTH BEHIND THE FRONT...AND QUICKLY
INCREASE AND BECOME GUSTY AFTER 12Z. GUSTS TO AROUND 25 KT ARE
LIKELY WITH OCCASIONAL GUSTS AT THE NYC TERMINALS APPROACHING 30
KT TUESDAY AFTERNOON.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KLGA FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KEWR FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KHPN FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
KISP FCSTER COMMENTS: OCCASIONAL GUSTS MAY BE HIGHER THAN FORECAST.
.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.TUESDAY NIGHT...VFR. NW TO N GUSTS 20-25KT...DIMINISHING AFTER 06Z.
.WEDNESDAY...VFR.
.THURSDAY...VFR. SW GUSTS 20-25KT.
.LATE THURSDAY NIGHT AND FRIDAY...MVFR POSSIBLE WITH A CHANCE
OF SHOWERS IN SHRA.
.SATURDAY...VFR.
&&
.MARINE...
A COLD FRONT MOVES THROUGH THIS MORNING...AND WINDS WILL SHIFT
AROUND TO THE NW/NW. NEARSHORE WINDS WILL BE STRONGER...BUT MOST
OF THE OPEN WATERS AWAY FROM LAND SHOULD REMAIN LIGHTER. THESE
WINDS MAY INCREASE BRIEFLY TO SCA CRITERIA LATE TONIGHT INTO EARLY
WEDNESDAY AS LOW PRESSURE PASSES WELL TO THE EAST AND HIGH
PRESSURE BUILDS TO THE NW. AS COOLER AIR MOVES IN...BETTER CHANCE
FOR GUSTS ON THE WATERS LATE TONIGHT. NOT ENOUGH CONFIDENCE THOUGH
FOR ANY SCA ISSUANCE AT THIS TIME.
SEAS GENERALLY REMAINS UNDER 5 FEET THROUGH WEDNESDAY. THE OUTER
PORTIONS OF THE OCEAN WATERS MAY APPROACH 5 FEET BRIEFLY LATE
TONIGHT INTO EARLY WEDNESDAY.
QUIET ON ALL WATERS WED NIGHT INTO THU NIGHT. THERE IS A CHANCE FOR
MARGINAL SCA CONDS ON THE OCEAN WATERS SOME TIME FRI INTO FRI NIGHT
AS A COLD FRONT MOVES SLOWLY ACROSS. TRANQUIL CONDS RETURN BY THE
WEEKEND AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.FIRE WEATHER...
A RED FLAG WARNING HAS BEEN ISSUED FOR THIS AFTERNOON AND INTO THE
EARLY EVENING DUE TO VERY DRY FUELS...MIN RH 25-30 PERCENT AND
WINDS GUSTS 20 TO 25 MPH.
DRY CONDITIONS ARE EXPECTED ONCE AGAIN ON WEDNESDAY AS RH VALUES
FALL INTO THE 20S DURING THE DAY. NORTH WINDS WILL RANGE FROM
5-10 MPH...AND WILL GIVE WAY TO COASTAL SEA BREEZES IN THE
AFTERNOON.
&&
.HYDROLOGY...
NO SIGNIFICANT RAINFALL THROUGH THURSDAY. A COLD FRONT MOVING
THROUGH FROM THU NIGHT INTO FRI NIGHT MAY BRING 1/10 TO 1/4 INCH
BASIN AVG QPF...WITH POTENTIAL FOR LOCALLY UP TO 1/2 INCH WITH
ANY LATE DAY TSTMS. NO FLOODING ISSUES ANTICIPATED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
CTZ005>012.
NY...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
NYZ067>075-078>081-176>179.
NJ...RED FLAG WARNING FROM NOON TODAY TO 8 PM EDT THIS EVENING FOR
NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...GOODMAN/PW
NEAR TERM...PW
SHORT TERM...PW
LONG TERM...GOODMAN
AVIATION...BC
MARINE...GOODMAN/PW
FIRE WEATHER...PW
HYDROLOGY...GOODMAN/PW
AREA FORECAST DISCUSSION
NWS TAUNTON MA
215 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT CROSSES THE REGION EARLY THIS MORNING WITH A BRIEF BAND
OF SCATTERED RAIN SHOWERS. DRY WEATHER FOLLOWS BUT CAN NOT RULE OUT
A FEW SPOT SHOWERS ACROSS EASTERN NEW ENGLAND LATE THIS AFTERNOON.
HIGH PRESSURE BUILDS OVER THE REGION WEDNESDAY AND THURSDAY. ANOTHER
COLD FRONT SWEEPS ACROSS NEW ENGLAND FRIDAY OR SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
215 AM UPDATE...
COLD FRONT DROPPING SOUTH FROM NORTHERN NEW ENGLAND WILL RESULT IN
MID LEVEL FORCING AND A BRIEF BAND OF RAIN SHOWERS MOVING ACROSS THE
REGION THROUGH 8 AM. RAINFALL WILL NOT LAST LONG IN A GIVEN LOCATION
AND GENERALLY ONLY LOOKING AT AMOUNTS OF A TRACE TO A FEW HUNDREDTHS
OF AN INCH. TEMPS THROUGH DAYBREAK WILL GENERALLY BE IN THE 40S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
915 PM UPDATE FOR TUESDAY...
SCATTERED SHOWERS SHOULD EXIT THE SOUTH COAST BY MID
MORNING...OTHERWISE MAINLY DRY WEATHER FOR MOST OF THE DAY. SHOULD
SEE A FAIR AMOUNT CUMULUS CLOUDS HANG TOUGH ACROSS EASTERN NEW
ENGLAND...BUT STILL PEAKS OF SUN EXPECTED. PLENTY OF SUNSHINE
SHOULD DEVELOP ACROSS THE INTERIOR THOUGH DURING THE AFTERNOON. HIGH
TEMPS SHOULD RECOVER INTO THE UPPER 50S AND 60S ACROSS THE
INTERIOR...BUT SEA BREEZES WILL MAKE IT TOUGH FOR THE IMMEDIATE
EASTERN MA COAST TO RISE MUCH PAST 50.
ONE THING WILL HAVE TO WATCH IS FOR A FEW SHOWERS AND PERHAPS EVEN
AN ISOLATED T-STORM OR TWO ACROSS THE EASTERN HALF OF OUR REGION
FROM MID AFTERNOON INTO THE EARLY EVENING HOURS. THE MODELS SHOWING
100 TO 200 J/KG OF CAPE WITH STEEP MID LEVEL LAPSE RATES. MOISTURE
IS A LIMITING FACTOR THOUGH AND CONVERGENCE IS WEAK...SO CONFIDENCE
ON WHETHER ANYTHING WILL DEVELOP IS LOW. THE LATEST HRRR HAS SOME
ACTIVITY SO WILL HAVE TO MONITOR CLOSELY. ALSO...GIVEN COLD TEMPS
ALOFT NOT OUT OF THE QUESTION FOR SOME GRAUPEL/SMALL HAIL IF
ANYTHING IS ABLE TO DEVELOP.
TUESDAY NIGHT...
DRIER AIR CONTINUES TO ARRIVE. MAINLY CLEAR SKIES WITH SEASONABLE
MIN TEMPERATURES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WEDNESDAY...
CANADIAN HIGH PRESSURE SINKS SOUTHEASTWARD INTO OUR AREA...ALLOWING
FOR MOSTLY SUNNY SKIES AND NEAR SEASONABLE TEMPERATURES. N/NW
BREEZE WILL KEEP LOW DEW POINTS IN PLACE.
MOSTLY CLEAR SKIES WEDNESDAY NIGHT...ACCOMPANIED BY LIGHT
WINDS...WILL ALLOW FOR DECOUPLING AND GOOD RADIATIONAL COOLING.
EXPECTING TEMPS TO DROP INTO MID 30S TO NEAR 40...BUT THERE IS A
CHANCE TEMPS MAY GET A BIT LOWER WHICH WOULD INTRODUCE THE
POTENTIAL FOR SOME FROST. PLEASE SEE THE CLIMATE SECTION FOR MORE
INFO ABOUT THE UPCOMING STARTING DATE FOR THE FROST/FREEZE WARNING
PROGRAM.
THURSDAY...
HIGH PRESSURE CENTER SHIFTS OFFSHORE...WITH THE APPROACH
OF A LOW PRESSURE SYSTEM THAT WILL BE CROSSING THRU THE GREAT LAKES
REGION. MODEL GUIDANCE IN AGREEMENT THAT PRECIPITATION HOLDS OFF
DURING THE DAY...BUT EXPECT TO SEE INCREASING CLOUDINESS FROM WEST
TO EAST. WILL HAVE CHANCE OF SHOWERS FOR THURSDAY NIGHT WITH
MOISTURE INCREASING AHEAD OF THE LOW/S ASSOCIATED COLD FRONT.
THURSDAY WILL BE NOTICEABLY WARMER...HIGHS GENERALLY UPPER 60S TO
LOW 70S. IF CLOUD COVER HOLDS OFF UNTIL VERY LATE IN THE DAY...COULD
BE A FEW DEGREES WARMER.
FRIDAY...
MODELS INDICATE COLD FRONT PASSES THROUGH SOUTHERN NEW ENGLAND
SOMETIME LATE FRIDAY INTO EARLY SATURDAY...WITH LOW PRESSURE
CENTER CROSSING THRU NORTHERN NEW ENGLAND/FAR SOUTHEAST CANADA.
MEANWHILE A SHORT WAVE PASSES THRU THE BASE OF THE UPPER
TROUGH...POTENTIALLY THRU SOUTHERN NEW ENGLAND. PRECIPITABLE WATER
INCREASES TO JUST OVER AN INCH. GFS SHOWS SOME INSTABILITY FOR
FRIDAY AFTERNOON...WITH LIFTED INDEX JUST BELOW 0...TT LOW 50S. SO
SHOWERS AND SOME THUNDERSTORMS LOOK TO BE POSSIBLE FRIDAY...WITH
THE POTENTIAL FOR BRIEF LOCALLY HEAVY RAIN. WILL CONTINUE WITH
CHANCE POPS FOR SHOWERS AND INTRODUCE ISOLATED THUNDER FOR THIS
FORECAST PACKAGE.
SATURDAY THRU MONDAY...
FRONT AND ASSOCIATED SHOWERS EXPECTED TO PUSH OFFSHORE
SATURDAY...ALLOWING FOR A MAINLY DRY DAY WITH HIGH PRESSURE
BUILDING IN FROM THE WEST. POSSIBILITY FOR A SECOND WEAKER FRONT
TO BRING SOME CLOUDS OR A PERIOD OF LIGHT PRECIPITATION LATER ON
IN THE WEEKEND...BUT THERE ARE MODEL DIFFERENCES ON THE TIMING AND
WHETHER OR NOT WE GET ANY QPF. MOST OF THIS 3 DAY PERIOD LOOKS TO
BE DRY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TODAY THROUGH WEDNESDAY/...
TODAY...MODERATE CONFIDENCE. MAINLY VFR THROUGH 12Z DESPITE A BRIEF
BAND OF SCATTERED RAIN SHOWERS ASSOCIATED WITH A COLD FRONT. BEHIND
THE FRONT A PERIOD OF SCATTERED TO BROKEN DECK OF LOW END VFR TO
MVFR CIGS EXPECTED INTO MID AFTERNOON. LOWER CIGS MOST LIKELY
ACROSS EASTERN NEW ENGLAND.
MAINLY VFR FROM MID TO LATE AFTERNOON WITH NNW WIND GUSTS OF 20 TO
30 KNOTS DEVELOPING ACROSS THE INTERIOR. A FEW SPOT SHOWERS WITH A
LOW RISK OF AN ISOLATED T-STORM POSSIBLE ACROSS EASTERN MA ON A SEA
BREEZE FRONT FROM MID TO LATE AFTERNOON INTO THE EARLY EVENING
HOURS.
TONIGHT AND WEDNESDAY...HIGH CONFIDENCE. VFR CONDITIONS. A PERIOD
OF NORTHERLY WIND GUSTS OF 20 TO 25 KNOTS POSSIBLE VERY LATE TONIGHT
INTO WED AM.
KBOS TAF...MODERATE CONFIDENCE IN TAF TODAY...FOLLOWED BY HIGH
CONFIDENCE TONIGHT AND WEDNESDAY.
KBDL TAF...HIGH CONFIDENCE.
OUTLOOK /WEDNESDAY NIGHT THROUGH SATURDAY/...
THURSDAY...HIGH CONFIDENCE. VFR.
FRIDAY...MODERATE CONFIDENCE. VFR WITH AREAS MVFR CIGS/VSBYS IN
SCATTERED SHOWERS. ISOLATED TSRA POSSIBLE.
SATURDAY...HIGH CONFIDENCE. CHANCE FOR SCATTERED SHOWERS W/MVFR CIGS
AND/OR VSBYS EARLY. OTHERWISE VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY/...HIGH CONFIDENCE.
PERSISTENT EAST FLOW ALONG THE EAST COAST OF MA THIS AFTERNOON.
WINDS DIMINISH A LITTLE TONIGHT...BEFORE INCREASING FROM THE NORTH
BEHIND A COLD FRONT LATE TONIGHT INTO TUESDAY MORNING. WEAK LOW
PRESSURE MOVES ACROSS THE WATERS LATE TONIGHT INTO TUESDAY...AND
SHOULD NOT BE A MAJOR FACTOR IN THE WEATHER OUTCOMES. BRIEF
PERIODS OF LOWER VISIBILITY IN SCATTERED SHOWERS. SEAS SHOULD
REMAIN LESS THAN 5 FEET...UNTIL LATE TUESDAY NIGHT ACROSS THE
OUTER COASTAL WATERS.
OUTLOOK /WEDNESDAY NIGHT THROUGH SATURDAY/...MODERATE-HIGH CONFIDENCE...
WEDNESDAY...
NORTH-NORTHWEST WINDS MAY GUST TO 25 KNOTS DURING WEDNESDAY MORNING
WITH 5 TO 7 FOOT SEAS MAINLY ON THE OUTER WATERS. SEAS SHOULD
GRADUALLY SUBSIDE DURING THE DAY. A SMALL CRAFT ADVISORY MAY BE
NEEDED.
THURSDAY THRU SATURDAY...
INCREASING SOUTHWEST WINDS AHEAD OF AN APPROACHING COLD FRONT WHICH
SHOULD CROSS THE WATERS SOMETIME FRIDAY NIGHT INTO SATURDAY. THIS
MAY BUILD SEAS WITH 5 TO 7 FOOT HEIGHTS. A SMALL CRAFT ADVISORY
MAY BE NEEDED FOR SEAS DURING FRIDAY INTO SATURDAY.
&&
.FIRE WEATHER...
TONIGHT AND TUESDAY...
MUCH COOLER WEATHER ALONG WITH A PERIOD OF SHOWERS TONIGHT NORTH
OF THE MASS PIKE ESPECIALLY. RH VALUES NOT AS LOW ON TUESDAY...EVEN
AS WINDS SHIFT TO THE N AND SKIES CLEAR. TEMPERATURES ABOUT 10-15
DEGREES LOWER THAN TODAY. MIN RH VALUES 25-40 PERCENT EXPECTED...
WITH GUSTY NORTH WINDS OF 20-30 MPH LATE IN THE AFTERNOON AND
EVENING. AFTER CONSULTATION WITH FIRE WEATHER PARTNERS...WE WILL
BE ISSUING A FIRE WEATHER WATCH FROM WORCESTER COUNTY WEST IN
MA...ALL OF NORTHERN CT...AND PORTIONS OF NORTHWEST RI.
WEDNESDAY AND THURSDAY...
TEMPERATURES WILL BE WARMER EACH DAY...REACHING THE 60S AND
AROUND 70 INLAND. WARMING AIR AND LOW DEW POINTS WILL MEAN LOW RH
VALUES. CONTINUE TO EXPECT INTERIOR MIN RH OF 20-25 PERCENT
WEDNESDAY...AND 25-30 PCT THURSDAY. COASTAL VALUES WILL BE 30-45 PCT
EACH DAY...EXCEPT HIGHER CAPE/ISLANDS. THE DEVELOPING WARMTH AND
DRYNESS WILL NEED TO BE MONITORED.
FRIDAY...
EXPECTING A SIGNIFICANT INCREASE IN DEW POINTS WITH SOUTHWEST WINDS
HEAD OF AN APPROACHING COLD FRONT. ALTHOUGH WARM...MIN RH MAINLY 50-
60 PERCENT. THE COLD FRONT PUSHES THRU THE AREA SOMETIME FRIDAY
AFTERNOON-FRIDAY NIGHT. ISOLATED THUNDERSTORMS ARE POSSIBLE WITH THE
FRONT.
&&
.CLIMATE...
THE FROST/FREEZE WARNING PROGRAM STARTS APRIL 21 FOR A LARGE PORTION
OF SOUTHERN NEW ENGLAND. THIS INCLUDES ALL OF RHODE ISLAND...EAST
COASTAL MA INCLUSIVE OF ALL OF SOUTHEAST MA...AND NORTHERN CT
FROM HARTFORD COUNTY EAST. FOR OTHER PORTIONS OF THE NWS TAUNTON
COUNTY WARNING AREA...THE FROST/FREEZE WARNING PROGRAM BEGINS IN
EARLY MAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR CTZ002>004.
MA...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR MAZ002>004-008>012-026.
RI...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR RIZ001-003.
MARINE...NONE.
&&
$$
SYNOPSIS...FRANK/BELK/NMB
NEAR TERM...FRANK
SHORT TERM...FRANK/BELK
LONG TERM...NMB
AVIATION...FRANK/NMB
MARINE...BELK/NMB
FIRE WEATHER...STAFF
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS NEW YORK NY
137 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT APPROACHES THE AREA TONIGHT...AND PASSES THROUGH
LATE TONIGHT INTO TUESDAY MORNING. HIGH PRESSURE BUILDS IN TUESDAY
NIGHT AND WEDNESDAY...AND MOVES OFF THE COAST THURSDAY. A COLD
FRONT WILL SLOWLY WORK ITS WAY THROUGH THE REGION LATE THURSDAY
NIGHT THROUGH LATE FRIDAY NIGHT. HIGH PRESSURE RETURNS FOR THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
PHASING PAC AND POLAR JET ENERGY WILL HAVE A TROUGH DIGGING FROM
ONTARIO INTO THE NORTHEAST OVERNIGHT. AT THE SURFACE...A WEAK LOW
PRES SYSTEM MOVING THROUGH SOUTHERN NEW ENGLAND WILL MOVE OFFSHORE
BY MORNING.
WITH BEST FORCING TRACKING TO THE NORTH OF THE REGION AND DEEP NW
FLOW...THIS FRONTAL PASSAGE WILL BE MOISTURE STARVED. NOT EXPECTING
MORE THAN A FEW LIGHT SHOWERS OR SPRINKLES WITH THE PASSAGE...BEST
CHANCE ACROSS EASTERN CT.
MINOR ADJUSTMENTS MADE FOR TEMPS/DEWS AND SKY BASED ON LATEST OBS
AND TRENDS. ALSO...BASED ON LATEST GUIDANCE AND RADAR HAVE BACKED
OFF ON POPS. HRRR IS THE MOST AGGRESSIVE INDICATING A LINE OF
SHOWERS TRACKING THROUGH FROM N TO S FROM THE LOWER HUDSON
VALLEY/NYC EWD...BUT THINK THIS IS OVERDONE. LATEST RUN HAS BACKED
OFF A BIT ON THIS.
CAA IS LAGGING BEHIND THE FRONT...AND WITH LOW-LEVELS BECOMING
MIXED IN WAKE OF FRONTAL PASSAGE...TEMPS WILL BE UNSEASONABLY
MILD...GENERALLY MID TO UPPER 40S...EXCEPT MID 50S IN NYC/NJ
METRO.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
DIGGING SHORTWAVE SWINGS THROUGH NEW ENGLAND TUESDAY AND OFFSHORE
TUE NIGHT. CLIPPER SYSTEM AND TRAILING COLD FRONT SLIDE OFFSHORE
TUESDAY MORNING. GUSTY NW WINDS AND GRADUAL CAA IN ITS WAKE AS
LOW STRENGTHENS AND HIGH PRESSURE BUILDS TOWARDS THE NE.
WITH OFFSHORE FLOW...LAGGING CAA...AND MOSTLY SUNNY AFTERNOON FOR
MOST OF THE REGION...EXPECT TEMPS TO WARM WELL INTO THE MID TO
UPPER 60S INTERIOR...UPPER 60S TO LOWER 70S FOR COASTAL PLAIN.
HAVE UNDERCUT MODEL TDS SEVERAL DEGREES BASED ON DEEP MIXING OF
CONTINENTAL AIRMASS. SEE FIRE WEATHER SECTIONS FOR RAPID BRUSH
FIRE SPREAD CONCERNS.
CANADIAN HIGH PRESSURE BUILDS SE TOWARDS THE REGION TUE NIGHT. CAA
ON GUSTY NW WINDS EXPECTED FOR FIRST HALF OF THE NIGHT...GRADUALLY
RELAXING LATE. LOWS NEAR SEASONABLE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRES BUILDS OVER THE AREA ON WEDNESDAY. WITH UPPER RIDGE
BUILDING OVER WESTERN NY/PA...CAN EXPECT ABUNDANT SUNSHINE AND NEAR
TO SLIGHTLY ABOVE NORMAL TEMPS WITH HIGHS IN THE LOW 60S FOR MOST
AREAS...AND IN THE MID TO UPPER 60S WEST OF THE HUDSON RIVER.
COASTAL AREAS WILL BE A FEW DEGREES COOLER...AND AFTERNOON SEA
BREEZES ARE LIKELY TO DEVELOP.
WITH CLEAR SKIES AND LIGHT WINDS WEDNESDAY NIGHT...OPTIMAL
RADIATIONAL COOLING CONDS EXPECTED...AND TEMPS WILL DROP INTO THE
30S ACROSS INTERIOR NORTHERN ZONES AND EASTERN LONG ISLAND. PATCHY
FROST MAY DEVELOP IN THOSE AREAS. OTHERWISE...LOWS WEDNESDAY NIGHT
WILL RANGE FROM MID TO UPPER 40S IN/AROUND NYC..AND IN THE LOW 40S
MOST ELSEWHERE.
THE CENTER OF THE HIGH MOVES OFFSHORE ON THURSDAY...AND THE
RESULTING SW FLOW WILL USHER A WARM AND MILD AIRMASS INTO THE REGION
FOR THE END OF THE WORK WEEK. HIGHS ON THURSDAY WILL BE WELL INTO
THE 60S...AND THEN HIGHS WILL CLIMB INTO THE 70S FOR MOST AREAS ON
FRIDAY.
MEANWHILE...LOW PRES MOVING THROUGH THE GREAT LAKES WILL DRAG A COLD
FRONT EAST. DUE TO THE OFFSHORE HIGH...IT WILL TAKE SOME TIME FOR
THE FRONT TO ACTUALLY MAKE IT TO THE LOCAL AREA. THERE ARE SOME
DIFFERENCES BETWEEN THE GFS AND THE ECMWF. THE GFS REMAINS THE
QUICKEST TO BRING THE FRONT INTO THE REGION THURSDAY NIGHT AND THEN
IT DEPARTS FRIDAY NIGHT. THE ECMWF HOLDS OFF ON BRINGING THE FRONT
INTO THE REGION UNTIL DURING THE DAY FRIDAY...AND DOES NOT CLEAR
EASTERN ZONES UNTIL SATURDAY MORNING. INSTABILITY PARAMETERS ARE
MARGINAL FOR CONVECTION...SO WILL NOT MENTION THUNDER IN THE
FORECAST AT THIS TIME...BUT WOULD NOT BE SURPRISED IF THERE IS A
RUMBLE OF THUNDER OR 2 FRIDAY AFTERNOON.
DUE TO THE UNCERTAINTY...FOLLOWED WPC GUIDANCE...WHICH GENERALLY
FOLLOWED THE ECMWF. PREFER THE SLOWER APPROACH OF THE FRONT DUE TO
THE STRENGTH OF THE OFFSHORE HIGH.
HIGH PRES THEN BUILDS IN BEHIND THE DEPARTING FRONT FOR THE WEEKEND.
TEMPS WILL GENERALLY RUN AT OR SLIGHTLY ABOVE NORMAL LEVELS.
ANOTHER WEAK FRONTAL SYSTEM MAY IMPACT THE REGION FOR THE START OF
THE NEW WORK WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL MOVE ACROSS THE AREA TERMINALS THROUGH 12Z. A
WAVE OF LOW PRESSURE ASSOCIATED WITH THE FRONT WILL ALSO PASS
ACROSS THE REGION.
THE FRONT WILL COME THROUGH MOSTLY DRY...HOWEVER A FEW LIGHT
SHOWERS WILL BE POSSIBLE WEST OF NYC. HIGH PRESSURE BUILDS BACK
INTO THE REGION THROUGH THE DAY TODAY.
LIGHT SOUTHWEST TO WEST WINDS AHEAD OF THE LOW AND COLD FRONT WILL
SHIFT TO THE NORTHWEST TO NORTH BEHIND THE FRONT...AND QUICKLY
INCREASE AND BECOME GUSTY AFTER 12Z. GUSTS TO AROUND 25 KT ARE
LIKELY WITH OCCASIONAL GUSTS AT THE NYC TERMINALS APPROACHING 30
KT TUESDAY AFTERNOON.
.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.TUESDAY NIGHT...VFR. NW TO N GUSTS 20-25KT...DIMINISHING AFTER 06Z.
.WEDNESDAY...VFR.
.THURSDAY...VFR. SW GUSTS 20-25KT.
.LATE THURSDAY NIGHT AND FRIDAY...MVFR POSSIBLE WITH A CHANCE
OF SHOWERS IN SHRA.
.SATURDAY...VFR.
&&
.MARINE...
SUB-ADVSY CONDS OVERNIGHT. BUOY 44025 HAS BEEN RANGING BETWEEN
4.5 AND 4.9 FT THE PAST FEW HOURS...HOWEVER A DECREASING TREND IS
EXPECTED OVERNIGHT AS THE ELY SWELL DIMINISHES. OTHER OCEAN BUOYS
ARE ALREADY DOWN TO 4 FT.
NW FLOW BEHIND COLD FRONTAL PASSAGE TUE MORNING WILL GRADUALLY
STRENGTHEN THROUGH THE DAY. MARGINAL SCA GUSTS POSSIBLE ACROSS
NEARSHORE WATERS DURING THE DAY.
BETTER POTENTIAL FOR SMALL CRAFT CONDITIONS ON THE OCEAN TUESDAY
NIGHT INTO WEDNESDAY MORNING WITH A GUSTY NW FLOW AND MARGINAL
SEAS BETWEEN HIGH PRES BUILDING OVER WESTERN NY/PA AND DEPARTING
LOW PRES NEAR 40N/60W. GRADIENT SLACKENS BY AFTERNOON...AND
TRANQUIL CONDS IN PLACE THROUGH THURSDAY.
NEXT CHANCE FOR SCA CONDS WILL BE FRIDAY INTO SATURDAY AS A COLD
FRONT MOVES ACROSS THE WATERS. TRANQUIL CONDS RETURN BY SATURDAY
AFTERNOON AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.FIRE WEATHER...
A FIRE WEATHER WATCH HAS BEEN ISSUED FOR TUE AFTERNOON DUE TO VERY
DRY FUELS...MIN RH 25-35 PERCENT AND WINDS GUSTS 20 TO 25 MPH.
DRY CONDS EXPECTED ONCE AGAIN ON WEDNESDAY AS SFC DEWPOINTS WILL
BE IN THE 20S...AND RH VALUES WILL FALL INTO THE 20S DURING THE
DAY. NORTH WINDS WILL RANGE FROM 5-10 MPH...AND WILL GIVE WAY TO
COASTAL SEA BREEZES IN THE AFTERNOON.
&&
.HYDROLOGY...
NO SIGNIFICANT RAINFALL THROUGH THURSDAY.
A COLD FRONT MOVING THROUGH THE REGION THURSDAY NIGHT THROUGH
SATURDAY MORNING MAY RESULT IN UP TO 1/4" QPF.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR CTZ005>012.
NY...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR NYZ067>075-078>081-176>179.
NJ...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
FORECAST UPDATE: PW
AVIATION: BC
AREA FORECAST DISCUSSION
NWS ALBANY NY
120 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT WILL BRING SOME LIGHT RAIN SHOWERS TO THE
REGION OVERNIGHT. BEHIND THE COLD FRONT...COOLER AND BREEZY
CONDITIONS WILL BE IN PLACE FOR TUESDAY. HIGH PRESSURE WILL PROVIDE
DRY WEATHER WITH COMFORTABLE TEMPERATURES ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 120 AM EDT...A COLD FRONT IS NOW SITUATED ACROSS THE
CATSKILLS...MID HUDSON VALLEY AND INTO BERKSHIRES...AND IT WILL
CONTINUE TO SETTLE SOUTHWARD OVER THE NEXT FEW HOURS. IR SATELLITEIMAGERY
SHOWS PLENTY OF CLOUDS FOR AREAS NEAR AND NORTH OF THE CAPITAL
REGION AND BERKSHIRES...WITH SOME BREAKS FOR THE CATSKILLS...MID
HUDSON VALLEY AND NW CT.
BEHIND THE BOUNDARY...A BAND OF RAIN SHOWERS IS ONGOING OVER THE
ADIRONDACKS...LAKE GEORGE REGION...AND INTO SOUTHERN VT. DRY LOW
LEVELS HAS PREVENTED MUCH OF THIS ACTIVITY FROM REACHING THE
GROUND. RADAR TRENDS AND THE LATEST 3KM HRRR SUGGESTS THIS
RAINFALL WILL CONTINUE TO MOVE SOUTH AND EASTWARD OVER THE NEXT
FEW HOURS. THROUGH THE REMAINDER OF THE OVERNIGHT HOURS...THE BEST
CHANCE OF SEEING A RAIN SHOWER WILL BE FOR AREAS NORTH OF
INTERSTATE 90. RAINFALL AMOUNTS WILL ONLY LAST A SHORT DURATION AT
ANY ONE PARTICULAR LOCATION...AND AMOUNTS LOOK TO ONLY BE A FEW
HUNDREDTHS OF AN INCH AT MOST. ANY RAINFALL SHOULD BE DONE BY
SUNRISE.
OVERNIGHT LOWS WILL RANGE FROM THE UPPER 30S OVER THE ADIRONDACKS
TO NEAR 50 IN THE MID HUDSON VALLEY. MOST AREAS LOOK TO SEE LOW
TEMPS IN THE MID TO UPPER 40S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
THE COLD FRONT SHOULD BE JUST SOUTH OF OUR REGION BY TUESDAY. IN ITS
WAKE...THERE COULD BE SOME RESIDUAL CLOUDS...AND PERHAPS ANOTHER
SPRINKLE OR TWO...MAINLY ACROSS THE HIGHER TERRAIN. OTHERWISE IT
WILL DRY WITH INCREASING SUNSHINE AND A NORTHWEST BREEZE. THE BREEZE
COULD GUST TO 30 MPH IN THE USUAL WINDY SPOTS...HIGHER
TERRAIN....MOHAWK VALLEY AND CAPITAL REGION.
TEMPERATURES WILL BE NOTICEABLY COOLER AS H850 TEMPS COOL TO ABOUT -
2C. HOWEVER...WITH GOOD MIXING VALLEYS LOOK TO CRACK THE 60S...50S
HIGHER TERRAIN. THESE VALUES ARE STILL SLIGHTLY ABOVE NORMAL.
HIGH PRESSURE WILL BUILD INTO THE REGION TOMORROW NIGHT THROUGH
WEDNESDAY. THIS WILL PROVIDE A MAINLY CLEAR SKY AND SLACKENING
WINDS. TEMPERATURES WILL TUMBLE TO THE 30S AT NIGHT. THE HIGHS ON
WEDNESDAY WILL BE 55 TO 60 ACROSS THE HIGHER TERRAIN...60 TO 65
VALLEYS.
WEDNESDAY NIGHT WILL FEATURE ANOTHER CLEAR CALM AND CHILLY NIGHT
IN THE 30S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AN UPPER LEVEL RIDGE...STILL IN PLACE FROM EARLIER...BREAKS DOWN
ACROSS THE EASTERN CONUS AND ALLOWS FOR THE UPSTREAM CUT OFF LOW TO
BECOME ENTRAINED INTO THE NORTHERN POLAR JET FOR THE LATER HALF OF
THIS WEEK. THIS WILL BRING INCREASING CLOUDS AND MOISTURE FOR
HIGHER POPS THROUGH THURSDAY INTO AT LEAST THE FIRST HALF OF FRIDAY.
SHOULD REMAIN RATHER MILD AS H850 TEMPS REMAIN AROUND +10C.
IN THE WAKE OF THIS PROGRESSIVE SYSTEM FRIDAY NIGHT AND INTO THE
WEEKEND...COLDER AIR ADVECTS INTO THE REGION AS WE RETURN H850 TEMPS
BELOW 0C. HOWEVER...WITH HIGH SUN ANGLE THOSE VALLEY TEMPERATURES
FOR THE AFTERNOON SHOULD REMAIN INTO THE 50S WITH 40S FOR THE
TERRAIN. HOWEVER...OVERNIGHT LOWS WILL DIP BACK INTO THE 30S WITH
20S FOR THE HIGHER TERRAIN. THERE IS SOME DISCREPANCY WITH RESPECT
TO MOISTURE QUICKLY ADVECTING INTO THE REGION WITHIN THE REGION OF
CONFLUENCE ACROSS THE GREAT LAKES REGION IN THE WAKE OF THE COLD
FRONT. THE GFS WOULD IMPLY CHANCE POPS FOR SATURDAY NIGHT INTO
SUNDAY WHERE BOUNDARY LAYER TEMPS MAY BE COLD ENOUGH FOR A LITTLE
LIGHT SNOW FOR THE HIGHER TERRAIN. THE ARRIVAL OF THE ECMWF ALSO
SUPPORTS THE GFS BUT DELAYED ABOUT 12-18 HOURS. FOR NOW...WE WILL
INTRODUCE SLIGHT CHANCE POPS THROUGH LATE SATURDAY NIGHT INTO
SUNDAY.
TEMPERATURES THROUGH THE WEEKEND WILL LIKELY AVERAGE JUST BELOW
NORMAL.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT CONTINUES TO MOVE SOUTHWARD ACROSS THE REGION AS
A WEAK AREA OF LOW PRESSURE MOVES EASTWARD ALONG THE BOUNDARY.
LIGHT SHOWERS ARE OCCURRING IN THE WAKE OF THE FRONT AND WILL
MOVE ALSO SOUTHWARD ACROSS THE AREA THROUGH THE EARLY MORNING
HOURS. THE SHOWERS WILL WEAKEN AND DISSIPATE AS THEY MOVE
FARTHER SOUTHWARD. HAVE SHOWERS AND MVFR CEILINGS IN KGFL TAF.
VCSH AND SCATTERED MVFR CLOUDS IN KALB AND KPSF TAFS WITH
NO MENTION IN THE KPOU TAF. CLOUD COVER WILL DECREASE AFTER
SUNRISE AND WITH CLEAR SKIES DEVELOPING FOR THE AFTERNOON.
THE PRESSURE GRADIENT WILL TIGHTEN UP ACROSS THE REGION
BETWEEN THE DEPARTING LOW AND AN ADVANCING HIGH AND ALONG
WITH GOOD MIXING WILL RESULT IN BREEZY AND GUSTY CONDITIONS
FROM THE NORTHWEST. EXPECTING SUSTAINED WINDS INCREASING TO
14 TO 18 KNOTS WITH GUSTS WELL INTO THE 20S TO NEAR 30 KNOTS.
WINDS WILL WEAKEN IN THE EVENING.
OUTLOOK...
WED-WED NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THU: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
THU NIGHT-FRI: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
FRI NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SAT: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
...A FIRE WEATHER WATCH HAS BEEN ISSUED FOR ALL OF EASTERN NEW
YORK AND ADJACENT WESTERN NEW ENGLAND FROM 100 PM TO 600 PM EDT ON
TUESDAY...
...LOW RELATIVE HUMIDITIES IN THE 15-25 PERCENT RANGE ON
WEDNESDAY AFTERNOON...
THERE HAS NOT BEEN SIGNIFICANT RAINFALL FOR OVER FIVE DAYS. A COLD
FRONT WILL CROSS THE REGION TONIGHT BUT WILL LIKELY NOT BRING A
QUARTER INCH OF RAINFALL TO REALLY ANY OUR REGION. THERE MIGHT BE A
TENTH OF AN INCH ACROSS PORTIONS OF THE ADIRONDACKS...WITH ONLY
A FEW HUNDREDTHS EXPECTED ELSEWHERE.
TOMORROW...THE WIND WILL INCREASE OUT OF THE NORTHWEST TO 10-15
MPH...GUSTING TO AROUND 25-30 MPH...HIGHEST ACROSS THE MOHAWK
VALLEY...HIGHER TERRAIN AND CAPITAL REGION. RH VALUES LOOK TO DROP
TO AROUND 30 PERCENT OR LESS.
PER COORDINATION WITH OUR MAIN FIRE WEATHER USERS...WE ISSUED A FIRE
WEATHER WATCH AGAIN FOR ALL AREAS...INCLUDING ADJACENT WESTERN NEW
ENGLAND.
THE WINDS WILL RELAX BACK DOWN TO AROUND 5 MPH OVERNIGHT
MONDAY...ALLOWING FOR A NEARLY FULL RECOVERY. ON WEDNESDAY...THE
WIND SHOULD LIGHTER...FROM THE NORTHWEST...5-15 MPH. RELATIVE
HUMIDITIES HOWEVER ONCE AGAIN WILL DROP TO VERY LOW LEVELS...
15-25 PERCENT.
BY THURSDAY...AS HIGH PRESSURE BEGINS TO MOVE EAST...ALLOWING FOR A
SOUTHERN BREEZE 5-15 MPH. AT THIS POINT...AFTERNOON RH VALUES LOOK A
LITTLE HIGHER THAN PREVIOUS DAY...DROPPING TO THE 30S.
THE NEXT CHANCE FOR SIGNIFICANT RAINFALL LOOKS TO BE FRIDAY.
&&
.HYDROLOGY...
NO HYDROLOGIC CONCERNS THROUGH THE REMAINDER OF THE WEEK.
A COLD FRONT WILL PASS THROUGH THE REGION EARLY THIS MORNING WITH
SOME LIGHT RAIN SHOWERS. MOST AREAS WILL ONLY SEE A FEW HUNDREDTHS
OF AN INCH AT MOST.
DRY WEATHER WILL RETURN FOR LATER THIS MORNING THROUGH MOST OF
THURSDAY. SOME ADDITIONAL RAIN SHOWERS ARE POSSIBLE FOR LATE
THURSDAY INTO FRIDAY AS A FRONTAL SYSTEM MOVES ACROSS THE REGION.
IT/S STILL TOO EARLY TO SAY JUST HOW MUCH RAINFALL WILL OCCUR WITH
THIS SYSTEM...BUT AMOUNTS WILL LIKELY VARY ACROSS THE REGION. DRY
WEATHER LOOKS TO RETURN FOR SATURDAY.
AS A RESULT...RIVER AND STREAM LEVELS WILL GENERALLY HOLD STEADY
OR SLOWLY FALL THROUGH THE WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FIRE WEATHER WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS
AFTERNOON FOR CTZ001-013.
NY...FIRE WEATHER WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS
AFTERNOON FOR NYZ032-033-038>043-047>054-058>061-063>066-
082>084.
MA...FIRE WEATHER WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS
AFTERNOON FOR MAZ001-025.
VT...FIRE WEATHER WATCH FROM 1 PM EDT THIS AFTERNOON THROUGH THIS
AFTERNOON FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...IAA
FIRE WEATHER...HWJIV
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1244 AM EDT TUE APR 19 2016
.SYNOPSIS...
A COLD FRONT APPROACHES THE AREA TONIGHT...AND PASSES THROUGH
LATE TONIGHT INTO TUESDAY MORNING. HIGH PRESSURE BUILDS IN TUESDAY
NIGHT AND WEDNESDAY...AND MOVES OFF THE COAST THURSDAY. A COLD
FRONT WILL SLOWLY WORK ITS WAY THROUGH THE REGION LATE THURSDAY
NIGHT THROUGH LATE FRIDAY NIGHT. HIGH PRESSURE RETURNS FOR THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
PHASING PAC AND POLAR JET ENERGY WILL HAVE A TROUGH DIGGING FROM
ONTARIO INTO THE NORTHEAST OVERNIGHT. AT THE SURFACE...A WEAK LOW
PRES SYSTEM MOVING THROUGH SOUTHERN NEW ENGLAND WILL MOVE OFFSHORE
BY MORNING.
WITH BEST FORCING TRACKING TO THE NORTH OF THE REGION AND DEEP NW
FLOW...THIS FRONTAL PASSAGE WILL BE MOISTURE STARVED. NOT EXPECTING
MORE THAN A FEW LIGHT SHOWERS OR SPRINKLES WITH THE PASSAGE...BEST
CHANCE ACROSS EASTERN CT.
MINOR ADJUSTMENTS MADE FOR TEMPS/DEWS AND SKY BASED ON LATEST OBS
AND TRENDS. ALSO...BASED ON LATEST GUIDANCE AND RADAR HAVE BACKED
OFF ON POPS. HRRR IS THE MOST AGGRESSIVE INDICATING A LINE OF
SHOWERS TRACKING THROUGH FROM N TO S FROM THE LOWER HUDSON
VALLEY/NYC EWD...BUT THINK THIS IS OVERDONE. LATEST RUN HAS BACKED
OFF A BIT ON THIS.
CAA IS LAGGING BEHIND THE FRONT...AND WITH LOW-LEVELS BECOMING
MIXED IN WAKE OF FRONTAL PASSAGE...TEMPS WILL BE UNSEASONABLY
MILD...GENERALLY MID TO UPPER 40S...EXCEPT MID 50S IN NYC/NJ
METRO.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
DIGGING SHORTWAVE SWINGS THROUGH NEW ENGLAND TUESDAY AND OFFSHORE
TUE NIGHT. CLIPPER SYSTEM AND TRAILING COLD FRONT SLIDE OFFSHORE
TUESDAY MORNING. GUSTY NW WINDS AND GRADUAL CAA IN ITS WAKE AS
LOW STRENGTHENS AND HIGH PRESSURE BUILDS TOWARDS THE NE.
WITH OFFSHORE FLOW...LAGGING CAA...AND MOSTLY SUNNY AFTERNOON FOR
MOST OF THE REGION...EXPECT TEMPS TO WARM WELL INTO THE MID TO
UPPER 60S INTERIOR...UPPER 60S TO LOWER 70S FOR COASTAL PLAIN.
HAVE UNDERCUT MODEL TDS SEVERAL DEGREES BASED ON DEEP MIXING OF
CONTINENTAL AIRMASS. SEE FIRE WEATHER SECTIONS FOR RAPID BRUSH
FIRE SPREAD CONCERNS.
CANADIAN HIGH PRESSURE BUILDS SE TOWARDS THE REGION TUE NIGHT. CAA
ON GUSTY NW WINDS EXPECTED FOR FIRST HALF OF THE NIGHT...GRADUALLY
RELAXING LATE. LOWS NEAR SEASONABLE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRES BUILDS OVER THE AREA ON WEDNESDAY. WITH UPPER RIDGE
BUILDING OVER WESTERN NY/PA...CAN EXPECT ABUNDANT SUNSHINE AND NEAR
TO SLIGHTLY ABOVE NORMAL TEMPS WITH HIGHS IN THE LOW 60S FOR MOST
AREAS...AND IN THE MID TO UPPER 60S WEST OF THE HUDSON RIVER.
COASTAL AREAS WILL BE A FEW DEGREES COOLER...AND AFTERNOON SEA
BREEZES ARE LIKELY TO DEVELOP.
WITH CLEAR SKIES AND LIGHT WINDS WEDNESDAY NIGHT...OPTIMAL
RADIATIONAL COOLING CONDS EXPECTED...AND TEMPS WILL DROP INTO THE
30S ACROSS INTERIOR NORTHERN ZONES AND EASTERN LONG ISLAND. PATCHY
FROST MAY DEVELOP IN THOSE AREAS. OTHERWISE...LOWS WEDNESDAY NIGHT
WILL RANGE FROM MID TO UPPER 40S IN/AROUND NYC..AND IN THE LOW 40S
MOST ELSEWHERE.
THE CENTER OF THE HIGH MOVES OFFSHORE ON THURSDAY...AND THE
RESULTING SW FLOW WILL USHER A WARM AND MILD AIRMASS INTO THE REGION
FOR THE END OF THE WORK WEEK. HIGHS ON THURSDAY WILL BE WELL INTO
THE 60S...AND THEN HIGHS WILL CLIMB INTO THE 70S FOR MOST AREAS ON
FRIDAY.
MEANWHILE...LOW PRES MOVING THROUGH THE GREAT LAKES WILL DRAG A COLD
FRONT EAST. DUE TO THE OFFSHORE HIGH...IT WILL TAKE SOME TIME FOR
THE FRONT TO ACTUALLY MAKE IT TO THE LOCAL AREA. THERE ARE SOME
DIFFERENCES BETWEEN THE GFS AND THE ECMWF. THE GFS REMAINS THE
QUICKEST TO BRING THE FRONT INTO THE REGION THURSDAY NIGHT AND THEN
IT DEPARTS FRIDAY NIGHT. THE ECMWF HOLDS OFF ON BRINGING THE FRONT
INTO THE REGION UNTIL DURING THE DAY FRIDAY...AND DOES NOT CLEAR
EASTERN ZONES UNTIL SATURDAY MORNING. INSTABILITY PARAMETERS ARE
MARGINAL FOR CONVECTION...SO WILL NOT MENTION THUNDER IN THE
FORECAST AT THIS TIME...BUT WOULD NOT BE SURPRISED IF THERE IS A
RUMBLE OF THUNDER OR 2 FRIDAY AFTERNOON.
DUE TO THE UNCERTAINTY...FOLLOWED WPC GUIDANCE...WHICH GENERALLY
FOLLOWED THE ECMWF. PREFER THE SLOWER APPROACH OF THE FRONT DUE TO
THE STRENGTH OF THE OFFSHORE HIGH.
HIGH PRES THEN BUILDS IN BEHIND THE DEPARTING FRONT FOR THE WEEKEND.
TEMPS WILL GENERALLY RUN AT OR SLIGHTLY ABOVE NORMAL LEVELS.
ANOTHER WEAK FRONTAL SYSTEM MAY IMPACT THE REGION FOR THE START OF
THE NEW WORK WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A WAVE OF LOW PRESSURE AND ASSOCIATED COLD FRONT ACROSS NORTHERN NEW
ENGLAND WILL MOVE SOUTH THROUGH THE TERMINALS FROM AROUND 06Z
THROUGH 12Z. THERE MAY BE A FEW SHOWERS WITH THE FRONT...ESPECIALLY
ACROSS SOUTHEASTERN CONNECTICUT AND EASTERN LONG ISLAND. HIGH
PRESSURE THEN BUILDS IN FROM THE NORTH THROUGH TUESDAY.
LIGHT SOUTHWEST TO WEST WINDS AHEAD OF THE LOW AND COLD FRONT WILL
SHIFT TO THE NORTHWEST TO NORTH BEHIND THE FRONT...AND QUICKLY
INCREASE AND BECOME GUSTY AFTER 12Z. GUSTS TO AROUND 25 KT ARE
LIKELY WITH OCCASIONAL GUSTS AT THE NYC TERMINALS APPROACHING 30 KT
TUESDAY AFTERNOON.
.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.TUESDAY NIGHT...VFR. NW TO N GUSTS 20-25KT...DIMINISHING AFTER 06Z.
.WEDNESDAY...VFR.
.THURSDAY...VFR. SW GUSTS 20-25KT.
.LATE THURSDAY NIGHT AND FRIDAY...MVFR POSSIBLE WITH A CHANCE
OF SHOWERS IN SHRA.
.SATURDAY...VFR.
&&
.MARINE...
SUB-ADVSY CONDS OVERNIGHT. BUOY 44025 HAS BEEN RANGING BETWEEN
4.5 AND 4.9 FT THE PAST FEW HOURS...HOWEVER A DECREASING TREND IS
EXPECTED OVERNIGHT AS THE ELY SWELL DIMINISHES. OTHER OCEAN BUOYS
ARE ALREADY DOWN TO 4 FT.
NW FLOW BEHIND COLD FRONTAL PASSAGE TUE MORNING WILL GRADUALLY
STRENGTHEN THROUGH THE DAY. MARGINAL SCA GUSTS POSSIBLE ACROSS
NEARSHORE WATERS DURING THE DAY.
BETTER POTENTIAL FOR SMALL CRAFT CONDITIONS ON THE OCEAN TUESDAY
NIGHT INTO WEDNESDAY MORNING WITH A GUSTY NW FLOW AND MARGINAL
SEAS BETWEEN HIGH PRES BUILDING OVER WESTERN NY/PA AND DEPARTING
LOW PRES NEAR 40N/60W. GRADIENT SLACKENS BY AFTERNOON...AND
TRANQUIL CONDS IN PLACE THROUGH THURSDAY.
NEXT CHANCE FOR SCA CONDS WILL BE FRIDAY INTO SATURDAY AS A COLD
FRONT MOVES ACROSS THE WATERS. TRANQUIL CONDS RETURN BY SATURDAY
AFTERNOON AS HIGH PRES BUILDS IN FROM THE WEST.
&&
.FIRE WEATHER...
A FIRE WEATHER WATCH HAS BEEN ISSUED FOR TUE AFTERNOON DUE TO VERY
DRY FUELS...MIN RH 25-35 PERCENT AND WINDS GUSTS 20 TO 25 MPH.
DRY CONDS EXPECTED ONCE AGAIN ON WEDNESDAY AS SFC DEWPOINTS WILL
BE IN THE 20S...AND RH VALUES WILL FALL INTO THE 20S DURING THE
DAY. NORTH WINDS WILL RANGE FROM 5-10 MPH...AND WILL GIVE WAY TO
COASTAL SEA BREEZES IN THE AFTERNOON.
&&
.HYDROLOGY...
NO SIGNIFICANT RAINFALL THROUGH THURSDAY.
A COLD FRONT MOVING THROUGH THE REGION THURSDAY NIGHT THROUGH
SATURDAY MORNING MAY RESULT IN UP TO 1/4" QPF.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR CTZ005>012.
NY...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR NYZ067>075-078>081-176>179.
NJ...FIRE WEATHER WATCH FROM NOON EDT TODAY THROUGH THIS EVENING
FOR NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
213 AM EDT TUE APR 19 2016
.AVIATION...
RECENT RADAR TRENDS AND MODEL RUNS OF THE HRRR ARE BOTH SHOWING
THE OFFSHORE AND NEARSHORE SHOWERS SLIDING SOUTHWARD SO VCSH HAS
BEEN REMOVED FROM ALL TAF SITES. WINDS AT ALL SITES HAVE DROPPED
OFF A BIT AND SHOULD REMAIN NORTHEASTERLY OVERNIGHT. A STRONG
SURFACE HIGH PRESSURE RIDGE THEN BUILDS INTO GEORGIA AND NORTH
FLORIDA LEADING TO WINDS SHIFTING BACK TO EASTERLY AND BECOMING
GUSTY WITH 20KT+ GUSTS BY MID TO LATE MORNING. ALSO AS THE HIGH
PRESSURE BUILDS IN WE WILL BE HAVING A DRIER MORE STABLE AIRMASS
THAN WE HAVE BEEN SEEING THE PAST FEW DAYS SO SHOWER CHANCES WILL
BE LIMITED DURING THE DAY.
/BH
&&
.PREV DISCUSSION... /ISSUED 1244 AM EDT TUE APR 19 2016/
UPDATE...
THE LONG PERIOD NORTHEAST SWELL IS GRADUALLY SUBSIDING, AND THE
HIGH SURF ADVISORY FOR ALL ATLANTIC BEACHES HAS BEEN ALLOWED TO
EXPIRE. HOWEVER...BEACHGOERS CAN STILL EXPERIENCE PERIODS OF ROUGH
CONDITIONS ALONG AREA BEACHES AS GUSTY WINDS CONTINUE THROUGH AT
LEAST TODAY. THE FORECAST PACKAGE HAS BEEN UPDATED TO REMOVE THE
HIGH SURF ADVISORY. THE REST OF THE FORECAST REMAINS ON TRACK.
/AR
PREV DISCUSSION... /ISSUED 815 PM EDT MON APR 18 2016/
UPDATE...SEVERAL ATLANTIC CONVERGENCE BANDS SET UP THIS
AFTERNOON BRINGING LIGHT SHOWERS ALONG THE EAST COAST, LIKELY
AIDED BY DAYTIME HEATING. THE LAST FEW VIS SAT IMAGES SUGGEST A
DOWNWARD TREND IN ACTIVITY THROUGH LATE EVENING, WITH MODELS
SHOWING BANDS PUSHING SOUTHWARDS WITH TIME. WILL ADD THE MENTION
OF ISOLATED SHOWERS IN THE FORECAST ALONG THE EAST COAST THROUGH
LATE EVENING TO ACCOUNT FOR CURRENT ACTIVITY.
OTHERWISE, MAIN CONCERNS WILL BE MARINE RELATED WITH NORTHEASTERLY
SWELL CONTINUING TO BRING HAZARDOUS MARINE CONDITIONS OVER THE
ATLANTIC ALONG WITH A HIGH RISK OF RIP CURRENTS. CONDITIONS WILL
SLOWLY IMPROVE OVERNIGHT, BUT EXPECT THREAT TO CONTINUE THROUGH
TUESDAY. /ALM
AVIATION...GUSTY NE FLOW CONTINUES WITH A FEW SHOWERS BRUSHING
EAST COAST, THOUGH CONDITIONS HAVE REMAINED VFR WHEN SHOWERS PASS
BY. WILL KEEP VCSH IN FORECAST OVERNIGHT FOR EAST COAST SITES
THOUGH MODELS SUGGEST MOST SHRA WILL MOVE SOUTH OF REGION
OVERNIGHT. WINDS BECOMING NNE 6-10KTS OVERNIGHT WITH THE POTENTIAL
FOR MORE INLAND SITES TO BECOME VARIABLE OR NNW AGAIN LATE
TONIGHT. WINDS INCREASE OUT OF THE ENE AFTER 14Z AGAIN, WITH GUSTS
UP TO 20KTS POSSIBLE FROM LATE MORNING THROUGH THE AFTERNOON. KAPF
MAY SEE A SEABREEZE AFTER 20Z WITH WINDS BECOMING NNW. /ALM
PREV DISCUSSION... /ISSUED 340 PM EDT MON APR 18 2016/
SYNOPSIS...HIGH PRESSURE WILL DOMINATE THROUGH THURSDAY. A COLD
FRONT WILL APPROACH FRIDAY AND MOVE THROUGH SOUTH FLORIDA
SATURDAY...BRINGING A CHANCE FOR SHOWERS AND POSSIBLY
THUNDERSTORMS.
SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
NORTHEASTERLY BREEZE HAVE CONTINUED THIS AFTERNOON...USHERING IN
RELATIVELY DRY AND MILD AIR INTO SOUTH FLORIDA. TEMPERATURES TODAY
HAVE BEEN SEVERAL DEGREES BELOW NORMAL ACROSS EASTERN PORTIONS OF
SOUTH FLORIDA...WITH MAXIMA TOPPING OUT AROUND 80 DEGREES. ACROSS
WESTERN SECTIONS...LESS INFLUENCED BY THE ATLANTIC
OCEAN...TEMPERATURES HAVE REACHED SEASONABLY WARM MID 80S. DIURNAL
CU FIELD SHOULD DIMINISH OVERNIGHT...WITH ONLY A FEW CLOUDS
IMPACTING ATLANTIC COASTAL AREAS. LOWS WILL CONTINUE TO RANGE FROM
UPPER 50S WESTERN INTERIOR TO NEAR 70F ALONG THE IMMEDIATE
ATLANTIC COAST.
HIGH PRESSURE RESPONSIBLE FOR RECENT WEATHER WILL REMAIN ANCHORED
OVER GEORGIA INTO WEDNESDAY NIGHT...MEANING VERY LITTLE CHANCE IN
WEATHER THROUGH THE SHORT TERM.
HIGH RISK OF RIP CURRENTS CONTINUES ALONG ATLANTIC BEACHES THROUGH
AT LEAST TUESDAY...AND MAY NEED TO BE EXTENDED FURTHER IN TIME.
LONG TERM /THURSDAY THROUGH SUNDAY NIGHT/...CHANGES IN WEATHER
BEGIN THURSDAY...AS HIPRES SLIDES EWD INTO ATLC. THIS WILL
INITIATE A WARMING TREND...AND ALLOW MOISTURE TO GRADUALLY RETURN
TO THE REGION. A SHORTWAVE TROUGH /REMNANTS OF CLOSED H5 LOPRES
OVER TEXAS TODAY/ WILL CROSS MID-ATLC FRIDAY INTO SATURDAY. AS IT
DOES...ATTENDANT COLD FRONT WILL MOVE THROUGH FLORIDA. ALTHOUGH NO
COOLING IS EXPECTED BEHIND IT...THE FEATURE WILL PROVIDE THE
CONVERGENCE NEEDED TO WORK WITH INSTABILITY AND MOISTURE PRESENT
TO INDUCE SCATTERED SHOWERS FRIDAY AND SATURDAY. SOME
THUNDERSTORMS ALSO APPEAR POSSIBLE. DRIER AIRMASS MAY AGAIN MOVE
INTO THE REGION FOR THE LATTER PORTION OF THE WEEKEND.
AVIATION...
HIGH PRESSURE TO THE NORTH WILL KEEP VFR CONDITIONS AT ALL SOUTH
FLORIDA TAF SITES THROUGH THE TAF PERIOD. AN EASTERLY WIND WILL
CONTINUE THROUGH TOMORROW, GUSTY IN THE AFTERNOON AT TIMES.
MARINE...IN ATLANTIC...NORTHEASTERLY SWELL OF UP TO 7 FEET WILL
ONLY SLOWLY SUBSIDE TONIGHT INTO TUESDAY. IN ADDITION...NE WIND OF
15 KT WILL PREVAIL. THUS...SCA WILL CONTINUE THROUGH AT LEAST
TONIGHT FOR ATLANTIC WATERS OFF MIAMI-DADE AND BROWARD
COUNTIES...AND THROUGH TUESDAY OFF THE PALM BEACH COUNTY COAST.
EVEN AFTER THE SWELL SUBSIDES MID-WEEK...NORTHEAST WIND MAY AGAIN
LEAD TO HAZARDOUS MARINE CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 67 80 69 / 0 0 0 0
FORT LAUDERDALE 80 69 80 72 / 0 0 0 0
MIAMI 81 68 81 71 / 0 0 0 0
NAPLES 83 62 85 63 / 0 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR FLZ168-172-173.
AM...SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR AMZ651-671.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR AMZ650-670.
GM...NONE.
&&
$$
SHORT TERM...99/BH
LONG TERM....99/AR
AVIATION...99/BH
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
829 PM EDT WED APR 20 2016
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL AND DISSIPATE OVER OR NEAR THE
CHARLESTON TRI-COUNTY AREA TONIGHT. ATLANTIC HIGH PRESSURE WILL
THEN PREVAIL THURSDAY INTO FRIDAY. A COLD FRONT WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...FOLLOWED BY HIGH PRESSURE INTO EARLY
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
EARLY WEDNESDAY EVENING...THE BACK DOOR COLD FRONT HAD ADVANCED
INTO THE CHARLESTON TRI-COUNTY REGION...DIVIDING E/NE WINDS
AND TEMPS IN THE 60S/70S TO THE NORTH/EAST FROM TEMPS IN THE
70S/80S SOUTH/WEST.
THIS COLD FRONT WILL IS EXPECTED TO STALL AND GRADUALLY
DISSIPATE OVER OR JUST SOUTH/WEST OF THE CHARLESTON TRI-COUNTY
AREA BY LATER THIS EVENING. THE REMNANTS OF THE FRONT WILL LINGER
WILL THROUGH SUNRISE WITH MODELS SHOWING LOW-LEVEL MOISTURE POOLING
IN ITS VICINITY. THIS COULD PROMOTE SOME STRATUS BUILD DOWN AND
POSSIBLY FOG AFTER MIDNIGHT...BUT RAP POINT SOUNDINGS AT
KCHS...KDYB AND KMKS ARE NOT OVERLY IMPRESSIVE FOR SIGNIFICANT
FOG FORMATION...WILL CONTINUE TO ASSESS. OTHERWISE...FORECASTS
INCLUDE PATCHY FOG FOR THE CHARLESTON TRI-COUNTY AREA AND
DEPICT MOSTLY CLOUDY SKIES FOR AREAS ALONG/NORTH OF I-26.
ELSEWHERE...CONDITIONS WILL FAVOR JUST SHALLOW GROUND FOG A FEW
HOURS PRIOR TO SUNRISE.
ANOTHER A-TYPICAL TEMPERATURE DISTRIBUTION IS ON TAP TONIGHT WITH
THE COOLEST CONDITIONS ONCE AGAIN OCCURRING ACROSS INTERIOR
SOUTHEAST GEORGIA...MORE SPECIFICALLY IN THE FORT STEWART-
LUDOWICI-DARIEN CORRIDOR. HIGH CLOUDS ARE FORECAST TO THIN ENOUGH
TO SUPPORT MODEST RADIATIONAL COOLING WITH TEMPERATURE LIKELY
CRATERING JUST BEFORE DAYBREAK. STRATUS SHOULD KEEP TEMPERATURES A
BIT MORE ELEVATED ACROSS THE NORTHERN ZONES. LOWS WILL RANGE FROM
THE UPPER 50S/NEAR 60 ACROSS THE CHARLESTON TRI-COUNTY AREA TO THE
MID 50S ACROSS THE DARIEN-FORT STEWART-LUDOWICI CORRIDOR.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...SURFACE HIGH PRESSURE IN THE ATLANTIC WILL BE SHIFTING
EASTWARD WHILE A RIDGE AXIS IS POSITIONED OVER THE EAST COAST.
MOISTURE GRADUALLY INCREASES AS WEAK CONVERGENCE SETS UP JUST
OFFSHORE. THIS MAY LEAD TO A FEW LIGHT SHOWERS OFFSHORE. IT IS NOT
OUT OF THE QUESTION THAT A STRAY LIGHT SHOWER COULD REACH NORTHERN
CHARLESTON COUNTY IN THE AFTERNOON...BUT THE PROBABILITIES IN THIS
OCCURRING ARE LOW. REGARDLESS...WE HAVE MAINTAINED A BRIEF PERIOD OF
SLIGHT CHANCE POPS IN THE FORECAST TO ACCOUNT FOR THIS. TEMPERATURES
WILL BE IN THE LOWER 80S AWAY FROM THE LOCALLY COOLER COAST.
INCREASING CLOUDS LATE IN THE DAY AND ESPECIALLY AT NIGHT SHOULD
KEEP LOWS MILD...IN THE LOW 60S.
FRIDAY...THE ATLANTIC SURFACE HIGH WILL BE JUST FAR ENOUGH SHORE TO
LOSE INFLUENCE OVER OUR AREA. INSTEAD THE DOMINANT FEATURE WILL
BECOME A TROUGH MOVING FROM THE GREAT LAKES REGION INTO THE
NORTHEAST. THIS FEATURE WILL PUSH A COLD FRONT TOWARDS OUR AREA.
S/SW WINDS AT THE SURFACE AND AROUND 25 KT OF SW FLOW AT 850 MB WILL
PUSH PWATS TO NEAR 1.50 INCHES. THIS COMBINED WITH SOME INSTABILITY
AND ENERGY FROM A PASSING SHORTWAVE WILL GENERATE SHOWERS AND
THUNDERSTORMS. THE SEVERE THREAT IS LOW BECAUSE INSTABILITY IS
UNIMPRESSIVE AND SHEAR IS WEAK. DESPITE CLOUDY SKIES...COMPRESSIONAL
HEATING AHEAD OF THE FRONT SHOULD ALLOW HIGHS TO REACH AROUND 80
DEGREES. MODELS HAVE COME INTO BETTER AGREEMENT WITH TIMING OF
FRONTAL PASSAGE...SHOWING THE FRONT CROSSING THE LOCAL AREA LATE
FRIDAY NIGHT INTO EARLY SATURDAY. ADJUSTED THE POPS AND WEATHER
GRIDS TO BETTER REFLECT THIS TIMING. PRECIPITATION WILL QUICKLY
DECREASE AS THE FRONT MOVES OFFSHORE EARLY SATURDAY MORNING. QPF
SHOULD GENERALLY BE AROUND 0.25 INCHES. FRIDAY NIGHT LOWS WILL BE
MILD AGAIN...IN THE LOWER 60S.
SATURDAY...SHORTWAVE ENERGY LAGGING BEHIND THE FRONT IN COMBINATION
WITH WEAK INSTABILITY MAY BE ENOUGH TO ALLOW A FEW SHOWERS/ISOLATED
THUNDERSTORMS TO DEVELOP IN THE AFTERNOON. SLIGHT CHANCE POPS REMAIN
IN THE FORECAST. HIGHS WILL RANGE FROM THE UPPER 70S IN THE
NORTH...TO THE LOWER 80S IN THE SOUTH.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD IN FROM THE NORTH ON SUNDAY BEFORE SHIFTING
INTO THE ATLANTIC BY MONDAY. THE FORECAST AREA WILL LARGELY REMAIN
UNDER THE INFLUENCE OF THE SURFACE HIGH THROUGH MIDDLE OF NEXT WEEK.
MODELS DO HINT THAT A BACKDOOR COLD FRONT MAY TRY TO DESCEND INTO
THE AREA LATE TUESDAY OR WEDNESDAY HOWEVER THERE ARE STILL LARGE
DISCREPANCIES BETWEEN MODELS ON TIMING AND EVOLUTION OF THIS
FEATURE. TEMPERATURES WILL BE ON A WARMING TREND THROUGH THE PERIOD
WITH HIGHS SOLIDLY IN THE 80S EACH AFTERNOON.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
VFR AT KSAV...WITH ONLY A LOW PROBABILITY FOR PATCHY GROUND FOG
TOWARD DAYBREAK THURSDAY. AT KCHS...PERIODS OF MVFR CEILINGS WILL
PERSIST TONIGHT INTO EARLY THU...AND IFR/LIFR CEILINGS AND
ASSOCIATED VSBY RESTRICTIONS CANNOT BE RULED OUT LATER TONIGHT.
A BACK DOOR COLD FRONT WILL STALL AND DISSIPATE CLOSE TO THE
TERMINAL LATER THIS EVENING INTO EARLY THURSDAY. AFTER THU AM...
VFR EXPECTED AT KCHS FOR THE BALANCE OF THE 00Z TAF PERIOD.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE POSSIBLE FRIDAY
INTO EARLY SATURDAY AS A COLD FRONT MOVES THROUGH THE AREA WITH
SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
TONIGHT...WINDS WILL GRADUALLY TURN ONSHORE ACROSS THE ENTIRE
MARINE AREA. IN THE WAKE OF A BACK DOOR COLD FRONT...EAST-
NORTHEAST WINDS 10-15 KT WITH GUSTS TO 20 KT WILL PREVAIL THIS
EVENING NORTH OF EDISTO BEACH...INCLUDING CHARLESTON HARBOR. AS
THIS FRONT STALL AND DISSIPATES...THE PRESSURE GRADIENT WILL
WEAKEN AND WINDS WILL DIMINISH ACROSS SC WATERS OVERNIGHT. PATCHY
FOG COULD EVEN DEVELOP LATER TONIGHT ACROSS SC NEAR SHORE WATERS
NORTH OF EDISTO BEACH...INCLUDING CHARLESTON HARBOR. SOUTH OF
EDISTO BEACH...S/SE WINDS 10 KT OR LESS COULD BECOME
LIGHT.VARIABLE AS THE PRESSURE GRADIENT REMAINS WEAK OVERNIGHT.
SEAS WILL RANGE FROM 1-3 FT NEAR SHORE WATERS...HIGHEST NORTH OF
CHARLESTON HARBOR...AND 2-4 FT BEYOND 20 NM.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL REMAIN THE
DOMINANT FEATURE THURSDAY INTO FRIDAY. SOUTH/SOUTHWEST WINDS WILL
INCREASE FRIDAY AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF AN
APPROACHING COLD FRONT...HOWEVER CONDITIONS WILL REMAIN BELOW SMALL
CRAFT ADVISORY CRITERIA. THE FRONT WILL CROSS THE WATERS EARLY
SATURDAY...FOLLOWED BY HIGH PRESSURE THROUGH EARLY NEXT WEEK. WINDS
THROUGH THE PERIOD WILL GENERALLY BE 15 KT OR LESS...WITH SEAS 2-4
FEET ON AVERAGE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...SPR
SHORT TERM...
LONG TERM...
AVIATION...SPR
MARINE...SPR
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
708 PM EDT WED APR 20 2016
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL AND DISSIPATE OVER OR NEAR THE
CHARLESTON TRI-COUNTY AREA TONIGHT. ATLANTIC HIGH PRESSURE WILL
THEN PREVAIL THURSDAY INTO FRIDAY. A COLD FRONT WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...FOLLOWED BY HIGH PRESSURE INTO EARLY
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
EARLY WEDNESDAY EVENING...THE BACK DOOR COLD FRONT HAD ADVANCED
INTO THE CHARLESTON TRI-COUNTY REGION...DIVIDING E/NE WINDS
AND TEMPS IN THE 60S/70S TO THE NORTH/EAST FROM TEMPS IN THE
70S/80S SOUTH/WEST.
THIS COLD FRONT WILL IS EXPECTED TO STALL AND GRADUALLY
DISSIPATE OVER OR JUST SOUTH/WEST OF THE CHARLESTON TRI-COUNTY
AREA BY LATER THIS EVENING. THE REMNANTS OF THE FRONT WILL LINGER
WILL THROUGH SUNRISE WITH MODELS SHOWING LOW-LEVEL MOISTURE POOLING
IN ITS VICINITY. THIS COULD PROMOTE SOME STRATUS BUILD DOWN AND
POSSIBLY FOG AFTER MIDNIGHT...BUT RAP POINT SOUNDINGS AT
KCHS...KDYB AND KMKS ARE NOT OVERLY IMPRESSIVE FOR SIGNIFICANT
FOG FORMATION...WILL CONTINUE TO ASSESS. OTHERWISE...FORECASTS
INCLUDE PATCHY FOG FOR THE CHARLESTON TRI-COUNTY AREA AND
DEPICT MOSTLY CLOUDY SKIES FOR AREAS ALONG/NORTH OF I-26.
ELSEWHERE...CONDITIONS WILL FAVOR JUST SHALLOW GROUND FOG A FEW
HOURS PRIOR TO SUNRISE.
ANOTHER A-TYPICAL TEMPERATURE DISTRIBUTION IS ON TAP TONIGHT WITH
THE COOLEST CONDITIONS ONCE AGAIN OCCURRING ACROSS INTERIOR
SOUTHEAST GEORGIA...MORE SPECIFICALLY IN THE FORT STEWART-
LUDOWICI-DARIEN CORRIDOR. HIGH CLOUDS ARE FORECAST TO THIN ENOUGH
TO SUPPORT MODEST RADIATIONAL COOLING WITH TEMPERATURE LIKELY
CRATERING JUST BEFORE DAYBREAK. STRATUS SHOULD KEEP TEMPERATURES A
BIT MORE ELEVATED ACROSS THE NORTHERN ZONES. LOWS WILL RANGE FROM
THE UPPER 50S/NEAR 60 ACROSS THE CHARLESTON TRI-COUNTY AREA TO THE
MID 50S ACROSS THE DARIEN-FORT STEWART-LUDOWICI CORRIDOR.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...SURFACE HIGH PRESSURE IN THE ATLANTIC WILL BE SHIFTING
EASTWARD WHILE A RIDGE AXIS IS POSITIONED OVER THE EAST COAST.
MOISTURE GRADUALLY INCREASES AS WEAK CONVERGENCE SETS UP JUST
OFFSHORE. THIS MAY LEAD TO A FEW LIGHT SHOWERS OFFSHORE. IT IS NOT
OUT OF THE QUESTION THAT A STRAY LIGHT SHOWER COULD REACH NORTHERN
CHARLESTON COUNTY IN THE AFTERNOON...BUT THE PROBABILITIES IN THIS
OCCURRING ARE LOW. REGARDLESS...WE HAVE MAINTAINED A BRIEF PERIOD OF
SLIGHT CHANCE POPS IN THE FORECAST TO ACCOUNT FOR THIS. TEMPERATURES
WILL BE IN THE LOWER 80S AWAY FROM THE LOCALLY COOLER COAST.
INCREASING CLOUDS LATE IN THE DAY AND ESPECIALLY AT NIGHT SHOULD
KEEP LOWS MILD...IN THE LOW 60S.
FRIDAY...THE ATLANTIC SURFACE HIGH WILL BE JUST FAR ENOUGH SHORE TO
LOSE INFLUENCE OVER OUR AREA. INSTEAD THE DOMINANT FEATURE WILL
BECOME A TROUGH MOVING FROM THE GREAT LAKES REGION INTO THE
NORTHEAST. THIS FEATURE WILL PUSH A COLD FRONT TOWARDS OUR AREA.
S/SW WINDS AT THE SURFACE AND AROUND 25 KT OF SW FLOW AT 850 MB WILL
PUSH PWATS TO NEAR 1.50 INCHES. THIS COMBINED WITH SOME INSTABILITY
AND ENERGY FROM A PASSING SHORTWAVE WILL GENERATE SHOWERS AND
THUNDERSTORMS. THE SEVERE THREAT IS LOW BECAUSE INSTABILITY IS
UNIMPRESSIVE AND SHEAR IS WEAK. DESPITE CLOUDY SKIES...COMPRESSIONAL
HEATING AHEAD OF THE FRONT SHOULD ALLOW HIGHS TO REACH AROUND 80
DEGREES. MODELS HAVE COME INTO BETTER AGREEMENT WITH TIMING OF
FRONTAL PASSAGE...SHOWING THE FRONT CROSSING THE LOCAL AREA LATE
FRIDAY NIGHT INTO EARLY SATURDAY. ADJUSTED THE POPS AND WEATHER
GRIDS TO BETTER REFLECT THIS TIMING. PRECIPITATION WILL QUICKLY
DECREASE AS THE FRONT MOVES OFFSHORE EARLY SATURDAY MORNING. QPF
SHOULD GENERALLY BE AROUND 0.25 INCHES. FRIDAY NIGHT LOWS WILL BE
MILD AGAIN...IN THE LOWER 60S.
SATURDAY...SHORTWAVE ENERGY LAGGING BEHIND THE FRONT IN COMBINATION
WITH WEAK INSTABILITY MAY BE ENOUGH TO ALLOW A FEW SHOWERS/ISOLATED
THUNDERSTORMS TO DEVELOP IN THE AFTERNOON. SLIGHT CHANCE POPS REMAIN
IN THE FORECAST. HIGHS WILL RANGE FROM THE UPPER 70S IN THE
NORTH...TO THE LOWER 80S IN THE SOUTH.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD IN FROM THE NORTH ON SUNDAY BEFORE SHIFTING
INTO THE ATLANTIC BY MONDAY. THE FORECAST AREA WILL LARGELY REMAIN
UNDER THE INFLUENCE OF THE SURFACE HIGH THROUGH MIDDLE OF NEXT WEEK.
MODELS DO HINT THAT A BACKDOOR COLD FRONT MAY TRY TO DESCEND INTO
THE AREA LATE TUESDAY OR WEDNESDAY HOWEVER THERE ARE STILL LARGE
DISCREPANCIES BETWEEN MODELS ON TIMING AND EVOLUTION OF THIS
FEATURE. TEMPERATURES WILL BE ON A WARMING TREND THROUGH THE PERIOD
WITH HIGHS SOLIDLY IN THE 80S EACH AFTERNOON.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
VFR AT KSAV...WITH ONLY A LOW PROBABILITY FOR PATCHY GROUND FOG
TOWARD DAYBREAK THURSDAY. AT KCHS...THE PROBABILITY FOR MVFR OR
LOWER CEILINGS AND ASSOCIATED VSBY RESTRICTIONS WILL INCREASE AS A
BACK DOOR COLD FRONT STALLS AND DISSIPATES CLOSE TO THE TERMINAL
LATER THIS EVENING INTO EARLY THURSDAY. FOR THE 00Z TAFS...WILL
MAINTAIN SCATTERED IFR/MVFR LEVEL CLOUDS AND VISIBILITY JUST ABOVE
MVFR LEVEL...BUT AMENDMENTS FOR WORSE CONDITIONS COULD EVENTUALLY
BE REQUIRED.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE POSSIBLE FRIDAY
INTO EARLY SATURDAY AS A COLD FRONT MOVES THROUGH THE AREA WITH
SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
TONIGHT...WINDS WILL GRADUALLY TURN ONSHORE ACROSS THE ENTIRE
MARINE AREA. IN THE WAKE OF A BACK DOOR COLD FRONT...EAST-
NORTHEAST WINDS 10-15 KT WITH GUSTS TO 20 KT WILL PREVAIL THIS
EVENING NORTH OF EDISTO BEACH...INCLUDING CHARLESTON HARBOR. AS
THIS FRONT STALL AND DISSIPATES...THE PRESSURE GRADIENT WILL
WEAKEN AND WINDS WILL DIMINISH ACROSS SC WATERS OVERNIGHT. PATCHY
FOG COULD EVEN DEVELOP LATER TONIGHT ACROSS SC NEAR SHORE WATERS
NORTH OF EDISTO BEACH...INCLUDING CHARLESTON HARBOR. SOUTH OF
EDISTO BEACH...S/SE WINDS 10 KT OR LESS COULD BECOME
LIGHT.VARIABLE AS THE PRESSURE GRADIENT REMAINS WEAK OVERNIGHT.
SEAS WILL RANGE FROM 1-3 FT NEAR SHORE WATERS...HIGHEST NORTH OF
CHARLESTON HARBOR...AND 2-4 FT BEYOND 20 NM.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL REMAIN THE
DOMINANT FEATURE THURSDAY INTO FRIDAY. SOUTH/SOUTHWEST WINDS WILL
INCREASE FRIDAY AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF AN
APPROACHING COLD FRONT...HOWEVER CONDITIONS WILL REMAIN BELOW SMALL
CRAFT ADVISORY CRITERIA. THE FRONT WILL CROSS THE WATERS EARLY
SATURDAY...FOLLOWED BY HIGH PRESSURE THROUGH EARLY NEXT WEEK. WINDS
THROUGH THE PERIOD WILL GENERALLY BE 15 KT OR LESS...WITH SEAS 2-4
FEET ON AVERAGE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...SPR
SHORT TERM...
LONG TERM...
AVIATION...SPR
MARINE...SPR
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1209 AM CDT TUE APR 19 2016
.SHORT TERM...
216 PM CDT
TONIGHT THROUGH THURSDAY NIGHT...
OUR STREAK OF CHAMBER OF COMMERCE WEATHER DAYS WILL GIVE
WAY TO COOLER AND SHOWERY CONDITIONS THROUGH MID-WEEK...AS THE
LARGE UPPER LOW OVER THE WESTERN CONUS SLOWLY DRIFTS EAST AND
FILLS TO AN OPEN TROUGH WHILE MOVING ACROSS THE FORECAST AREA
THROUGH THURSDAY.
AFTERNOON SURFACE ANALYSIS DEPICTS A WEST-EAST COLD FRONT OVER
NORTHERN WISCONSIN AND LAKE MICHIGAN. THIS FRONT IS PROGGED TO SAG
SOUTH THROUGH THIS EVENING...EVENTUALLY COMBINING WITH RESIDUAL
LAKE BREEZE ONSHORE WINDS AND PUSHING INTO FAR NORTHERN/NORTHEAST
IL BY MIDNIGHT AND EVENTUALLY ACROSS SOUTHERN TIER OF CWA COUNTIES
BY 12Z TUESDAY. THIS WILL SET UP EASTERLY SYNOPTIC WINDS ACROSS
MOST OF THE AREA WITH COOLER TEMPS TUESDAY...AS SURFACE HIGH
PRESSURE BUILDS SOUTHEAST ACROSS ONTARIO AND THE GREAT LAKES
BEHIND THE FRONT. MEANWHILE THE CLOSED UPPER LOW TO OUR WEST WILL
BEGIN TO DRIFT EAST...WITH SOUTH-SOUTHWEST FLOW ADVECTING MOISTURE
INTO THE REGION AND OVER THE LOW-LEVEL BAROCLINIC BOUNDARY
ASSOCIATED WITH THE FRONT. PRECIP POTENTIAL LOOKS TO INCREASE LATE
TONIGHT ESPECIALLY ACROSS THE WESTERN AND SOUTHWESTERN PARTS OF
THE CWA AS A SMALLER SCALE SHORT WAVE ROTATES NORTH-NORTHEAST
AROUND THE MAIN UPPER LOW CIRCULATION AND BRINGS A SLUG OF HIGHER
THETA-E AIR AND INCREASING MOIST CONVERGENCE ON THE ELEVATED
FRONTAL SLOPE. MID-LEVEL LAPSE RATES ARE NOT VERY IMPRESSIVE
THROUGH TUESDAY MORNING...SUGGESTING THE BEST POTENTIAL FOR
THUNDER WILL REMAIN OFF TO THE WEST OF THE CWA ACROSS EASTERN IA.
FARTHER EAST...OUR LOW LEVEL EAST-NORTHEAST FLOW WILL ALSO PROVIDE
RELATIVELY DRY AIR IN THE LOW-LEVELS WHICH WILL LIMIT EASTWARD
EXTENT OF PRECIP PER FORECAST SOUNDINGS ACROSS OUR EASTERN CWA.
PERIODS OF SHOWERS...AND A FEW THUNDERSTORMS...WILL CONTINUE
ACROSS THE AREA THROUGH THURSDAY AS UPPER LOW CONTINUES TO MOVE
SLOWLY EAST AND SOUTH-NORTH ORIENTED PLUME OF MOISTURE SPREADS
INTO THE FORECAST AREA. AS EXPECTED...GUIDANCE DIFFERS WITH
HANDLING OF THE SMALLER SCALE SHORT WAVES WHICH WILL MODULATE
PERIODS OF GREATER SHOWER COVERAGE ACROSS THE AREA...THOUGH MODELS
DO SHOW SOME AGREEMENT IN FOCUSING A PERIOD OF STRONGER FORCING
FROM LATE WEDNESDAY MORNING THROUGH PERHAPS LATE WEDNESDAY
AFTERNOON OR EARLY EVENING. LAPSE RATES ARE ALSO MORE FAVORABLE
FOR SCATTERED THUNDERSTORMS DURING THIS PERIOD ON WEDNESDAY AS
WELL...ESPECIALLY ACROSS THE WESTERN PORTIONS OF THE CWA. SURFACE
LOW ASSOCIATED WITH APPROACHING UPPER LOW/TROUGH TRACKS FROM
EASTERN IA INTO SOUTHERN WI OR THE IL/WI BORDER REGION WEDNESDAY
EVENING...ALLOWING WINDS TO SHIFT SOUTH-SOUTHEAST ACROSS AREA AND
TEMPORARILY LIFT THE FRONT BACK NORTH AS A WARM FRONT BEFORE
TRAILING COLD FRONT PUSHES THROUGH ON THURSDAY. MILD/MOIST WARM
SECTOR WILL CONTINUE TO SUPPORT ISOLATED OR SCATTERED THUNDERSTORM
DEVELOPMENT AHEAD OF THE COLD FRONT ON THURSDAY...THOUGH FORECAST
MLCAPE VALUES ARE GENERALLY LESS THAN 500 J/KG. WHILE COVERAGE
WILL LIKELY NOT BE UNIFORM ACROSS THE FORECAST AREA...MODEL RUN
QPF TOTALS THROUGH THURSDAY EVENING INDICATE FROM ROUGHLY 0.60 TO
1.30 INCHES FOR SOME SPOTS...WITH THESE HIGHER AMOUNTS GENERALLY
ACROSS THE FAR WEST/SOUTHWEST PARTS OF THE FORECAST AREA.
SCATTERED SHOWERS AND THUNDERSTORMS SHOULD DIMINISH QUICKLY
THURSDAY EVENING WITH THE SURFACE COLD FRONT AND UPPER TROUGH AXIS
MOVING EAST OF THE AREA.
WITH EASTERLY FLOW ACROSS NORTHERN PARTS OF THE CWA TUESDAY A
LARGE TEMPERATURE DIFFERENCE IS EXPECTED FROM NORTH TO SOUTH.
TEMPS ACROSS FAR NORTHERN IL ARE EXPECTED TO RANGE FROM THE MID-
50S NEAR THE LAKE TO THE LOW-MID 60S WELL INLAND...WHILE SOUTH OF
I-80 HIGHS SHOULD REACH THE LOW-MID 70S. WINDS SHIFTING SOUTH-
SOUTHEAST WEDNESDAY AND SOUTHWEST-WEST BEHIND THE COLD FRONT
THURSDAY SHOULD RESULT IN SMALLER DIFFERENCES...WITH MID-UPPER 60S
NORTH AND NEAR/AROUND 70 SOUTH.
RATZER
&&
.LONG TERM...
216 PM CDT
FRIDAY THROUGH MONDAY...
UPPER TROUGH CONTINUES TO MOVE AWAY FROM THE AREA FRIDAY...WITH
LARGE SCALE PATTERN EVOLVING INTO A DEEP UPPER TROUGH/LOW OVER
EASTERN CANADA AND NEW ENGLAND...AND AN UPPER RIDGE FROM TEXAS TO
THE WESTERN CANADIAN PRAIRIES. THIS RESULTS IN A NORTHWESTERLY JET
STREAM ACROSS THE UPPER MIDWEST AND GREAT LAKES REGION. WEAK
SURFACE HIGH PRESSURE MOVES ACROSS THE AREA FRIDAY INTO EARLY
SATURDAY...BEFORE ANOTHER WEAK COLD FRONT SAGS SOUTH ACROSS THE
AREA SATURDAY NIGHT OR EARLY SUNDAY MORNING. GUIDANCE HAS TRENDED
FARTHER SOUTH WITH THE LOCATION OF THIS FRONT AND NOT UNLIKE OUR
COLD FRONT EARLY IN THE WEEK...THE BOUNDARY APPEARS TO BECOME
NEARLY STATIONARY FROM WEST-EAST ACROSS OR JUST SOUTH OF THE CWA
SUNDAY. THUS AFTER A COUPLE OF DRY DAYS FRIDAY AND
SATURDAY...PRECIP THREAT LOOKS TO INCREASE AGAIN ALONG THIS
BAROCLINIC ZONE SUNDAY AND CONTINUE MONDAY AS ANOTHER UPPER TROUGH
AND ASSOCIATED SURFACE LOW ADVANCE SLOWLY EAST ACROSS THE PLAINS.
ANOTHER SHARP GRADIENT IN TEMPS IS LIKELY FROM NORTH TO SOUTH
ACROSS THE SURFACE FRONTAL ZONE...AND LOOKS MUCH COOLER FOR SUNDAY
AND MONDAY THAN PREVIOUS FORECASTS WERE FRONT WAS FARTHER NORTH.
RATZER
&&
.AVIATION...
FOR THE 06Z TAFS...
A BACK DOOR COLD FRONT IS CURRENTLY MOVING ACROSS THE TAF
SITES...WITH WINDS BECOMING NORTHEASTERLY ACROSS NORTHERN ILLINOIS
IN ITS WAKE. WINDS OF 10 TO 13 KT ARE EXPECTED OVERNIGHT...WITH A
FEW HIGHER GUSTS POSSIBLE. WINDS WILL REMAIN EAST-NORTHEASTERLY 10
TO 15 KT ACROSS THE AREA DURING THE DAY TUESDAY AS SURFACE HIGH
PRESSURE DOMINATES OVER THE UPPER GREAT LAKES REGION. A STORM SYSTEM
TO OUR WEST WILL EVENTUALLY BRING MORE INCLEMENT WEATHER TO THE
TERMINALS. HOWEVER...IT LOOKS LIKE MUCH OF THIS WEATHER WILL HOLD
OFF UNTIL WEDNESDAY. ASIDE FROM A SMALL POSSIBILITY OF A FEW LIGHT
SHOWERS OR SPRINKLES OVER THE AREA TODAY...I THINK MOST AREAS WILL
STAY DRY WITH VFR CIGS ABOVE 8,000 TO 10,000 FT AGL.
KJB
&&
.MARINE...
216 PM...ONE LARGE AREA OF HIGH PRESSURE OVER THE EASTERN THIRD
OF THE U.S. WILL MOVE SOUTHEAST TONIGHT AND TUESDAY WHILE A SECOND
STRONGER AREA OF HIGH PRESSURE MOVES ACROSS ONTARIO TUESDAY AND
ACROSS THE EASTERN LAKES AND NEW ENGLAND TUESDAY NIGHT INTO
WEDNESDAY. IN BETWEEN...A COLD FRONT WILL MOVE SOUTH ACROSS LAKE
MICHIGAN TONIGHT. WEAK LOW PRESSURE WILL MOVE FROM THE CENTRAL
PLAINS TUESDAY NIGHT TO WISCONSIN THURSDAY MORNING. THE COLD FRONT
WILL LIFT BACK NORTH AS A WARM FRONT WEDNESDAY. THE LOW WILL THEN
MOVE NORTHEAST INTO QUEBEC THURSDAY NIGHT. STRONGER NORTHERLY
WINDS WILL DEVELOP AS THIS LOW DEPARTS AND HIGH PRESSURE BUILDS
ACROSS ONTARIO AND THE UPPER MIDWEST. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1126 PM CDT MON APR 18 2016
.UPDATE...
Issued at 1027 PM CDT Mon Apr 18 2016
Surge of moisture advancing eastward along a trough/frontal
boundary late this evening, with a jump in dew points of about
10-15 degrees extending from near Galesburg to Winchester. LAPS
sounding from Quincy showing the column significantly moistening
over the last couple hours, while humidity levels just east of
this boundary still only about 40-50% at this late hour. Have
tweaked the hourly PoP grids to limit the evening slight chances
from about Peoria-Jacksonville, and overnight have removed the
PoP`s east of a Bloomington-Taylorville line. Have also removed
thunder chances, with no lightning activity being observed to our
west and little in the way of MUCAPE available. Dew point grids
were also significantly adjusted to reflect the timing of this
boundary, primarily west of I-55.
UPDATE Issued at 824 PM CDT Mon Apr 18 2016
Area of rain is starting to cross into far west central Illinois
this hour, but ceilings are above 9,000 feet there so amounts are
fairly light initially. Evening soundings from our office and
Davenport IA show quite a bit of dry air below 20,000 feet that
will need to be overcome, so have made some adjustments to the PoP
trends and basically limited the 30% or higher to along and west
of the Illinois River valley this evening, before increasing them
after midnight. Latest HRRR guidance bring more of the showers
into the area after midnight, and mainly west of I-55. Also made
some adjustments to the thunder chances and limited them to after
midnight, across the western CWA.
&&
.SHORT TERM...(Tonight)
ISSUED AT 245 PM CDT Mon Apr 18 2016
The upper level ridge will finally start to break down across the
central portion of the country as the broad upper low over the
Rockies starts to make its way east towards the Mississippi Valley
later tonight. The leading band of showers well out ahead of the
upper low will track east and into parts of west central Illinois
late tonight and crawl its way east into parts of central and
east central Illinois on Tuesday. With the increase in cloud cover
tonight and a light southerly flow, temperatures will not be as cool
as the past few mornings with early morning lows expected to range
from the lower 50s far north to the upper 50s over the southwest.
.LONG TERM...(Tuesday through Monday)
ISSUED AT 245 PM CDT Mon Apr 18 2016
The initial band of showers will continue to edge east across
our area on Tuesday. In addition, a weak frontal boundary will
slip south through our northern counties during the day which may
help to develop additional showers and isolated storms during the
afternoon, but instability parameters, mid level lapse rates and
shear look weak at this time. Highest POPs will remain over the
west Tuesday night but as shortwave energy rotates northeast into
our area from the upper low on Wednesday and Wednesday night,
POPs will increase to likely over a large part of the forecast
area. As the weakening upper level shortwave shifts across the
area Thursday, the better rain chances shift into our east. The
actual upper trof axis takes until late Thursday night or early
Friday morning to shift east of the state, as a result, will
continue to carry at least low chance POPs during this time frame.
Temperatures will cool a bit from what we have been seeing the
past several days due to the cloud cover and periodic shower
activity, but still average above normal. We may see another 80
degrees over far southeast Illinois tomorrow afternoon as that
part of the forecast area will not see much if any rainfall and
the cloud cover will not be as thick. After that, temperatures
drop back into the mid 60s to low 70s for the remainder of the
week.
With the upper level trof off to our east on Friday, we should see a
period of pleasant weather again on Friday and Saturday as upper
level ridging builds back into the Midwest in response to another
trof moving into the Rockies. After Saturday night or early Sunday,
confidence drops off as models show some significant spread,
especially with the placement of the surface boundary across the
Midwest into early next week. Shower and thunderstorm chances
will increase to our north on Saturday night and gradually work
their way south into next week as the boundary settles south
across our area, with a rather active looking pattern setting up,
at least into the first half of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1126 PM CDT Mon Apr 18 2016
Rain showers over west central Illinois have been reaching the
ground as far east as KMQB as of 04Z, but the areas just east of
there remain very dry in the low levels and precipitation at
KPIA/KSPI likely to hold off until about 08-10Z or so. Not feeling
as confident on the prospects of MVFR conditions, with KPIA most
likely to be close enough to a warm front for this to be a
concern. Have included a TEMPO group for MVFR ceilings early
Tuesday afternoon there, but kept the remaining sites with
ceilings 5000 feet or higher. The threat of showers will diminish
late in the period, with ceilings rising closer to 10,000 feet for
a time.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Smith
LONG TERM...Smith
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1226 PM MDT TUE APR 19 2016
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
EARLY MORNING WV IMAGERY SHOWS LARGE UPPER LOW CENTERED NEAR THE
CO/WY WHICH EXTENDS ACROSS THE CENTRAL ROCKIES AND PLAINS. WV
IMAGERY SHOWS EMBEDDED SHORTWAVE ROTATING AROUND THE CENTER IN
EASTERN COLORADO. RAP SHOWS A STRONG PV 1.5 HEIGHT ANOMALY IN
EASTERN COLORADO HIGHLIGHTING TROPOPAUSE FOLD/STRONG SUBSIDENT
REGION BUILDING INTO SOUTHEAST COLORADO.
THIS MORNING-TODAY...INITIAL FORECAST CONCERN IS ON PRECIP TYPE
AND AMOUNTS. SURFACE TEMPERATURES AND RAP WET BULB TEMPS VARY
WILDLY AND PRECIP TYPE MAY END UP BEING MUCH MORE DYNAMIC THAN
PREVIOUSLY THOUGHT AS POCKETS OF WARMER TEMPERATURES HAVE ADVECTED
NORTHWARD...WHILE MODERATE PRECIP BANDS HAVE COOLED TEMP PROFILES
IN SOME LOCATIONS TO SUPPORT RAIN/SNOW MIX (POSSIBLE COMPLETE
CHANGE OVER). RESULT HAS BEEN MAINLY RAIN...WITH A FEW LOCATIONS
CHANGING OVER BRIEFLY.
FROM A SNOWFALL PERSPECTIVE...WEBCAMS IN REGIONS OF EASTERN
COLORADO THAT HAVE RECEIVED SNOW ONLY SHOW LIGHT PRECIP
ACCUMULATIONS IN GRASS...WITH WARM ROAD SURFACES REMAINING WET. IF
COMPLETE CHANGE OVER TO SNOW OCCURS IN OUR WESTERN CWA WE COULD
SEE AN INCH OR TWO...HOWEVER CONFIDENCE IS LOW THAT WE WOULD SEE
THIS IN ALL BUT A FEW ISOLATED LOCATIONS...AND WARM GROUND
TEMPERATURES ARE GOING TO DO A LOT TO LIMIT THE IMPACTS.
TREND IN LATEST GUIDANCE HAS BEEN TO DOWNPLAY QPF AMOUNTS SLIGHTLY
THROUGH THE MORNING HOURS...WHILE SPEEDING UP EXIT OF PRECIP FROM
THE WEST TO THE EAST IN THE 15-21Z TIME PERIOD. CONSIDERING THE
STRONG REGION OF SUBSIDENCE AND DRYING MID LEVELS ASSOCIATED WITH
TROPOPAUSE FOLD THIS PROGRESSIVE TREND SEEMS REASONABLE. HIGH POPS
ARE STILL REASONABLE...BUT I ADJUSTED TIMING FOR THE LATER PART OF
THE DAY TO SPEED UP DROP OFF IN PRECIP COVERAGE. DESPITE PRECIP
ENDING SOONER LINGERING LOW LEVEL CLOUD COVER WOULD LIKELY LIMIT
DAYTIME LAPSE RATES...AND CONFIDENCE IN THUNDERSTORM DEVELOPMENT
IS LOW. IF THERE IS ANY CLEARING WE COULD SEE A FEW WEAK
THUNDERSTORMS DEVELOP. THIS CLEARING WOULD BE ALSO BE NECESSARY
FOR ANY NON SUPERCELL TORNADO THREAT (VERY LOW CONFIDENCE AT THIS
TIME).
TONIGHT-WEDNESDAY NIGHT...OUR CWA SHOULD BE BETWEEN EMBEDDED
SHORTWAVE TROUGHS/VORT MAXES WITH PRECIP DIMINISHING OVERNIGHT
BEFORE NEXT SHORTWAVE TROUGH/REGION OF UPPER LEVEL DIVERGENCE
MOVES INTO THE REGION FROM THE NORTHWEST WEDNESDAY ON BACK SIDE
OF UPPER LOW (AS IT TRANSITIONS EAST). DURING THE NIGHT TONIGHT WE
COULD SEE A PERIOD OF FOG DEVELOP BEHIND INITIAL SHORTWAVE TROUGH
AS SURFACE HIGH PRESSURE STRENGTHENS ALONG CO/KS BORDER. THERE
SHOULD BE A LULL IN PRECIP BEFORE INCREASING CHANCES DURING THE
DAY. MODELS SHOW A LITTLE BIT BETTER INSTABILITY.
THURSDAY-THURSDAY NIGHT...SHORTWAVE RIDGING WILL BE IN PLACE
DURING THESE PERIODS WITH DRY CONDITIONS AND WARMER HIGH
TEMPERATURES (UPPER 60S/AROUND 70).
.LONG TERM...(FRIDAY THROUGH MONDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
FRIDAY-FRIDAY NIGHT...ELONGATED UPPER RIDGE AXIS EXTENDING FROM
PARTS OF ALASKA SOUTH ALONG THE CONTINENTAL DIVE INTO MEXICO
DRIFTS EVER SO SLOWLY EAST THROUGH THE PERIOD AS A LOW PRESSURE
SYSTEM MOVES INTO SOUTHERN CALIFORNIA. LITTLE IF ANY CLOUDINESS
DURING THE DAY WITH SOUTH WINDS AROUND 15 MPH AND AFTERNOON
TEMPERATURES IN THE LOW TO MID 70S. A FEW HIGH CLOUDS MAY MOVE IN
FROM THE WEST DURING THE NIGHT WITH LOW TEMPERATURES RANGING FROM
THE LOW TO MID 40S IN FAR EASTERN COLORADO...MID 40S TO AROUND 50
ELSEWHERE. NO PRECIPITATION EXPECTED.
SATURDAY-SATURDAY NIGHT...GENERAL IDEA IS FOR THE UPPER RIDGE AXIS
TO SLOWLY MOVE INTO CENTRAL KANSAS DURING THE DAY THEN TOWARD
EASTERN KANSAS AS THE LOW PRESSURE SYSTEM SLOWLY MOVES EAST.
GFS/GEM MODELS HAVE THE LOW OVER SOUTHWEST ARIZONA BY DAYS THEN
INTO NEW MEXICO OVERNIGHT WHILE THE ECMWF HAS IT OVER NORTHERN
UTAH THEN WYOMING. SOME MID AND HIGH CLOUDS EXPECTED TO MOVE INTO
THE WESTERN 1/2 OF THE AREA DURING THE AFTERNOON WITH A PARTLY
CLOUDY SKY OVERNIGHT. A DRY FORECAST EXPECTED...HOWEVER GFS/ECMWF
850MB TEMPERATURES WARM ABOUT 5C FROM FRIDAYS READINGS SUPPORTING
HIGH TEMPERATURES IN THE MID 70S TO LOW 80S...POSSIBLY HIGHER IF
MEX GUIDANCE IS CORRECT. LOW TEMPERATURES IN THE MID 40S TO NEAR
50 FOR FAR EASTERN COLORADO...LOW TO MID 50S ELSEWHERE.
SUNDAY-SUNDAY NIGHT...APPEARS THE EXTENDED FORECAST PROCEDURE IS
LATCHING ON TO THE GFS/GEM MODELS WHICH MOVE THE UPPER LOW INTO
SOUTH CENTRAL COLORADO DURING THE DAY THEN SOUTHWEST KANSAS
OVERNIGHT. HAVE SOME SLIGHT CHANCE POPS ADVERTISED DURING THE DAY
INCREASING A TAD DURING THE NIGHT. AFTERNOON TEMPERATURES REMAIN
WARM WITH LOW TO UPPER 70S WITH OVERNIGHT LOWS IN THE LOW 40S TO
LOW 50S (WEST TO EAST ACROSS THE AREA).
MONDAY-MONDAY NIGHT...FORECAST WEIGHTED TOWARD THE GFS. UPPER LOW
FORECAST TO LIFT INTO NORTHEAST KANSAS BY THE END OF THE DAY THEN
SLOWLY NORTHEAST WHILE ANOTHER UPPER LOW IS FORECAST TO SPIN ITS
WAY SLOWLY SOUTH OVER THE PACIFIC NORTHWEST. NORTHERLY WINDS
EXPECTED WHICH WILL COOL AFTERNOON TEMPERATURES INTO THE UPPER 60S
TO LOW 70S UNDER A MOSTLY CLOUDY SKY. WILL HAVE SOME LOW CHANCE
POPS AS WELL FOR THUNDERSTORMS. QUITE A BIT OF CLOUDINESS
CONTINUES OVERNIGHT WITH LOWS IN THE LOW TO MID 40S AND A
CONTINUED SMALL CHANCE FOR LIGHT RAIN/RAIN SHOWERS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1213 PM MDT TUE APR 19 2016
SCATTERED SHOWERS MOVING THROUGH THE TERMINALS THROUGH THIS
AFTERNOON WILL GRADUALLY DECREASE IN COVERAGE AS THE UPPER LOW
MOVES AWAY. MVFR CEILINGS MAY BRIEFLY RISE TO VFR WITH
SHOWERS...BUT EXPECTING MVFR TO PREVAIL FOR THE MOST PART THROUGH
THE AFTERNOON. THIS EVENING SHOWERS WILL DIMINISH AND CEILINGSIMPROVE
TO VFR. HOWEVER...OVERNIGHT PATCHY FOG AND LOW CEILINGS MAY RETURN
TO BOTH KGLD AND KMCK WITH LIGHT UPSLOPE WINDS AND VERY MOIST
CONDITIONS. THIS MAY RESULT IN A FEW HOURS OF MVFR OR IFR
CONDITIONS AROUND SUNRISE...IMPROVING BY MID MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...024
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1218 PM MDT TUE APR 19 2016
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
EARLY MORNING WV IMAGERY SHOWS LARGE UPPER LOW CENTERED NEAR THE
CO/WY WHICH EXTENDS ACROSS THE CENTRAL ROCKIES AND PLAINS. WV
IMAGERY SHOWS EMBEDDED SHORTWAVE ROTATING AROUND THE CENTER IN
EASTERN COLORADO. RAP SHOWS A STRONG PV 1.5 HEIGHT ANOMALY IN
EASTERN COLORADO HIGHLIGHTING TROPOPAUSE FOLD/STRONG SUBSIDENT
REGION BUILDING INTO SOUTHEAST COLORADO.
THIS MORNING-TODAY...INITIAL FORECAST CONCERN IS ON PRECIP TYPE
AND AMOUNTS. SURFACE TEMPERATURES AND RAP WET BULB TEMPS VARY
WILDLY AND PRECIP TYPE MAY END UP BEING MUCH MORE DYNAMIC THAN
PREVIOUSLY THOUGHT AS POCKETS OF WARMER TEMPERATURES HAVE ADVECTED
NORTHWARD...WHILE MODERATE PRECIP BANDS HAVE COOLED TEMP PROFILES
IN SOME LOCATIONS TO SUPPORT RAIN/SNOW MIX (POSSIBLE COMPLETE
CHANGE OVER). RESULT HAS BEEN MAINLY RAIN...WITH A FEW LOCATIONS
CHANGING OVER BRIEFLY.
FROM A SNOWFALL PERSPECTIVE...WEBCAMS IN REGIONS OF EASTERN
COLORADO THAT HAVE RECEIVED SNOW ONLY SHOW LIGHT PRECIP
ACCUMULATIONS IN GRASS...WITH WARM ROAD SURFACES REMAINING WET. IF
COMPLETE CHANGE OVER TO SNOW OCCURS IN OUR WESTERN CWA WE COULD
SEE AN INCH OR TWO...HOWEVER CONFIDENCE IS LOW THAT WE WOULD SEE
THIS IN ALL BUT A FEW ISOLATED LOCATIONS...AND WARM GROUND
TEMPERATURES ARE GOING TO DO A LOT TO LIMIT THE IMPACTS.
TREND IN LATEST GUIDANCE HAS BEEN TO DOWNPLAY QPF AMOUNTS SLIGHTLY
THROUGH THE MORNING HOURS...WHILE SPEEDING UP EXIT OF PRECIP FROM
THE WEST TO THE EAST IN THE 15-21Z TIME PERIOD. CONSIDERING THE
STRONG REGION OF SUBSIDENCE AND DRYING MID LEVELS ASSOCIATED WITH
TROPOPAUSE FOLD THIS PROGRESSIVE TREND SEEMS REASONABLE. HIGH POPS
ARE STILL REASONABLE...BUT I ADJUSTED TIMING FOR THE LATER PART OF
THE DAY TO SPEED UP DROP OFF IN PRECIP COVERAGE. DESPITE PRECIP
ENDING SOONER LINGERING LOW LEVEL CLOUD COVER WOULD LIKELY LIMIT
DAYTIME LAPSE RATES...AND CONFIDENCE IN THUNDERSTORM DEVELOPMENT
IS LOW. IF THERE IS ANY CLEARING WE COULD SEE A FEW WEAK
THUNDERSTORMS DEVELOP. THIS CLEARING WOULD BE ALSO BE NECESSARY
FOR ANY NON SUPERCELL TORNADO THREAT (VERY LOW CONFIDENCE AT THIS
TIME).
TONIGHT-WEDNESDAY NIGHT...OUR CWA SHOULD BE BETWEEN EMBEDDED
SHORTWAVE TROUGHS/VORT MAXES WITH PRECIP DIMINISHING OVERNIGHT
BEFORE NEXT SHORTWAVE TROUGH/REGION OF UPPER LEVEL DIVERGENCE
MOVES INTO THE REGION FROM THE NORTHWEST WEDNESDAY ON BACK SIDE
OF UPPER LOW (AS IT TRANSITIONS EAST). DURING THE NIGHT TONIGHT WE
COULD SEE A PERIOD OF FOG DEVELOP BEHIND INITIAL SHORTWAVE TROUGH
AS SURFACE HIGH PRESSURE STRENGTHENS ALONG CO/KS BORDER. THERE
SHOULD BE A LULL IN PRECIP BEFORE INCREASING CHANCES DURING THE
DAY. MODELS SHOW A LITTLE BIT BETTER INSTABILITY.
THURSDAY-THURSDAY NIGHT...SHORTWAVE RIDGING WILL BE IN PLACE
DURING THESE PERIODS WITH DRY CONDITIONS AND WARMER HIGH
TEMPERATURES (UPPER 60S/AROUND 70).
.LONG TERM...(FRIDAY THROUGH MONDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
FRIDAY-FRIDAY NIGHT...ELONGATED UPPER RIDGE AXIS EXTENDING FROM
PARTS OF ALASKA SOUTH ALONG THE CONTINENTAL DIVE INTO MEXICO
DRIFTS EVER SO SLOWLY EAST THROUGH THE PERIOD AS A LOW PRESSURE
SYSTEM MOVES INTO SOUTHERN CALIFORNIA. LITTLE IF ANY CLOUDINESS
DURING THE DAY WITH SOUTH WINDS AROUND 15 MPH AND AFTERNOON
TEMPERATURES IN THE LOW TO MID 70S. A FEW HIGH CLOUDS MAY MOVE IN
FROM THE WEST DURING THE NIGHT WITH LOW TEMPERATURES RANGING FROM
THE LOW TO MID 40S IN FAR EASTERN COLORADO...MID 40S TO AROUND 50
ELSEWHERE. NO PRECIPITATION EXPECTED.
SATURDAY-SATURDAY NIGHT...GENERAL IDEA IS FOR THE UPPER RIDGE AXIS
TO SLOWLY MOVE INTO CENTRAL KANSAS DURING THE DAY THEN TOWARD
EASTERN KANSAS AS THE LOW PRESSURE SYSTEM SLOWLY MOVES EAST.
GFS/GEM MODELS HAVE THE LOW OVER SOUTHWEST ARIZONA BY DAYS THEN
INTO NEW MEXICO OVERNIGHT WHILE THE ECMWF HAS IT OVER NORTHERN
UTAH THEN WYOMING. SOME MID AND HIGH CLOUDS EXPECTED TO MOVE INTO
THE WESTERN 1/2 OF THE AREA DURING THE AFTERNOON WITH A PARTLY
CLOUDY SKY OVERNIGHT. A DRY FORECAST EXPECTED...HOWEVER GFS/ECMWF
850MB TEMPERATURES WARM ABOUT 5C FROM FRIDAYS READINGS SUPPORTING
HIGH TEMPERATURES IN THE MID 70S TO LOW 80S...POSSIBLY HIGHER IF
MEX GUIDANCE IS CORRECT. LOW TEMPERATURES IN THE MID 40S TO NEAR
50 FOR FAR EASTERN COLORADO...LOW TO MID 50S ELSEWHERE.
SUNDAY-SUNDAY NIGHT...APPEARS THE EXTENDED FORECAST PROCEDURE IS
LATCHING ON TO THE GFS/GEM MODELS WHICH MOVE THE UPPER LOW INTO
SOUTH CENTRAL COLORADO DURING THE DAY THEN SOUTHWEST KANSAS
OVERNIGHT. HAVE SOME SLIGHT CHANCE POPS ADVERTISED DURING THE DAY
INCREASING A TAD DURING THE NIGHT. AFTERNOON TEMPERATURES REMAIN
WARM WITH LOW TO UPPER 70S WITH OVERNIGHT LOWS IN THE LOW 40S TO
LOW 50S (WEST TO EAST ACROSS THE AREA).
MONDAY-MONDAY NIGHT...FORECAST WEIGHTED TOWARD THE GFS. UPPER LOW
FORECAST TO LIFT INTO NORTHEAST KANSAS BY THE END OF THE DAY THEN
SLOWLY NORTHEAST WHILE ANOTHER UPPER LOW IS FORECAST TO SPIN ITS
WAY SLOWLY SOUTH OVER THE PACIFIC NORTHWEST. NORTHERLY WINDS
EXPECTED WHICH WILL COOL AFTERNOON TEMPERATURES INTO THE UPPER 60S
TO LOW 70S UNDER A MOSTLY CLOUDY SKY. WILL HAVE SOME LOW CHANCE
POPS AS WELL FOR THUNDERSTORMS. QUITE A BIT OF CLOUDINESS
CONTINUES OVERNIGHT WITH LOWS IN THE LOW TO MID 40S AND A
CONTINUED SMALL CHANCE FOR LIGHT RAIN/RAIN SHOWERS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1213 PM MDT TUE APR 19 2016
SCATTERED SHOWERS MOVING THROUGH THE TERMINALS THROUGH THIS
AFTERNOON WILL GRADUALLY DECREASE IN COVERAGE AS THE UPPER LOW
MOVES AWAY. MVFR CEILINGS MAY BRIEFLY RISE TO VFR WITH
SHOWERS...BUT EXPECTING MVFR TO PREVAIL FOR THE MOST PART THROUGH
THE AFTERNOON. THIS EVENING SHOWERS WILL DIMINISH AND CEILINGSIMPROVE
TO VFR. HOWEVER...OVERNIGHT PATCHY FOG AND LOW CEILINGS MAY RETURN
TO BOTH KGLD AND KMCK WITH LIGHT UPSLOPE WINDS AND VERY MOIST
CONDITIONS. THIS MAY RESULT IN A FEW HOURS OF MVFR OR IFR
CONDITIONS AROUND SUNRISE...IMPROVING BY MID MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...024
AREA FORECAST DISCUSSION
NWS GOODLAND KS
524 AM MDT TUE APR 19 2016
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
EARLY MORNING WV IMAGERY SHOWS LARGE UPPER LOW CENTERED NEAR THE
CO/WY WHICH EXTENDS ACROSS THE CENTRAL ROCKIES AND PLAINS. WV
IMAGERY SHOWS EMBEDDED SHORTWAVE ROTATING AROUND THE CENTER IN
EASTERN COLORADO. RAP SHOWS A STRONG PV 1.5 HEIGHT ANOMALY IN
EASTERN COLORADO HIGHLIGHTING TROPOPAUSE FOLD/STRONG SUBSIDENT
REGION BUILDING INTO SOUTHEAST COLORADO.
THIS MORNING-TODAY...INITIAL FORECAST CONCERN IS ON PRECIP TYPE
AND AMOUNTS. SURFACE TEMPERATURES AND RAP WET BULB TEMPS VARY
WILDLY AND PRECIP TYPE MAY END UP BEING MUCH MORE DYNAMIC THAN
PREVIOUSLY THOUGHT AS POCKETS OF WARMER TEMPERATURES HAVE ADVECTED
NORTHWARD...WHILE MODERATE PRECIP BANDS HAVE COOLED TEMP PROFILES
IN SOME LOCATIONS TO SUPPORT RAIN/SNOW MIX (POSSIBLE COMPLETE
CHANGE OVER). RESULT HAS BEEN MAINLY RAIN...WITH A FEW LOCATIONS
CHANGING OVER BRIEFLY.
FROM A SNOWFALL PERSPECTIVE...WEBCAMS IN REGIONS OF EASTERN
COLORADO THAT HAVE RECEIVED SNOW ONLY SHOW LIGHT PRECIP
ACCUMULATIONS IN GRASS...WITH WARM ROAD SURFACES REMAINING WET. IF
COMPLETE CHANGE OVER TO SNOW OCCURS IN OUR WESTERN CWA WE COULD
SEE AN INCH OR TWO...HOWEVER CONFIDENCE IS LOW THAT WE WOULD SEE
THIS IN ALL BUT A FEW ISOLATED LOCATIONS...AND WARM GROUND
TEMPERATURES ARE GOING TO DO A LOT TO LIMIT THE IMPACTS.
TREND IN LATEST GUIDANCE HAS BEEN TO DOWNPLAY QPF AMOUNTS SLIGHTLY
THROUGH THE MORNING HOURS...WHILE SPEEDING UP EXIT OF PRECIP FROM
THE WEST TO THE EAST IN THE 15-21Z TIME PERIOD. CONSIDERING THE
STRONG REGION OF SUBSIDENCE AND DRYING MID LEVELS ASSOCIATED WITH
TROPOPAUSE FOLD THIS PROGRESSIVE TREND SEEMS REASONABLE. HIGH POPS
ARE STILL REASONABLE...BUT I ADJUSTED TIMING FOR THE LATER PART OF
THE DAY TO SPEED UP DROP OFF IN PRECIP COVERAGE. DESPITE PRECIP
ENDING SOONER LINGERING LOW LEVEL CLOUD COVER WOULD LIKELY LIMIT
DAYTIME LAPSE RATES...AND CONFIDENCE IN THUNDERSTORM DEVELOPMENT
IS LOW. IF THERE IS ANY CLEARING WE COULD SEE A FEW WEAK
THUNDERSTORMS DEVELOP. THIS CLEARING WOULD BE ALSO BE NECESSARY
FOR ANY NON SUPERCELL TORNADO THREAT (VERY LOW CONFIDENCE AT THIS
TIME).
TONIGHT-WEDNESDAY NIGHT...OUR CWA SHOULD BE BETWEEN EMBEDDED
SHORTWAVE TROUGHS/VORT MAXES WITH PRECIP DIMINISHING OVERNIGHT
BEFORE NEXT SHORTWAVE TROUGH/REGION OF UPPER LEVEL DIVERGENCE
MOVES INTO THE REGION FROM THE NORTHWEST WEDNESDAY ON BACK SIDE
OF UPPER LOW (AS IT TRANSITIONS EAST). DURING THE NIGHT TONIGHT WE
COULD SEE A PERIOD OF FOG DEVELOP BEHIND INITIAL SHORTWAVE TROUGH
AS SURFACE HIGH PRESSURE STRENGTHENS ALONG CO/KS BORDER. THERE
SHOULD BE A LULL IN PRECIP BEFORE INCREASING CHANCES DURING THE
DAY. MODELS SHOW A LITTLE BIT BETTER INSTABILITY.
THURSDAY-THURSDAY NIGHT...SHORTWAVE RIDGING WILL BE IN PLACE
DURING THESE PERIODS WITH DRY CONDITIONS AND WARMER HIGH
TEMPERATURES (UPPER 60S/AROUND 70).
.LONG TERM...(FRIDAY THROUGH MONDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
FRIDAY-FRIDAY NIGHT...ELONGATED UPPER RIDGE AXIS EXTENDING FROM
PARTS OF ALASKA SOUTH ALONG THE CONTINENTAL DIVE INTO MEXICO
DRIFTS EVER SO SLOWLY EAST THROUGH THE PERIOD AS A LOW PRESSURE
SYSTEM MOVES INTO SOUTHERN CALIFORNIA. LITTLE IF ANY CLOUDINESS
DURING THE DAY WITH SOUTH WINDS AROUND 15 MPH AND AFTERNOON
TEMPERATURES IN THE LOW TO MID 70S. A FEW HIGH CLOUDS MAY MOVE IN
FROM THE WEST DURING THE NIGHT WITH LOW TEMPERATURES RANGING FROM
THE LOW TO MID 40S IN FAR EASTERN COLORADO...MID 40S TO AROUND 50
ELSEWHERE. NO PRECIPITATION EXPECTED.
SATURDAY-SATURDAY NIGHT...GENERAL IDEA IS FOR THE UPPER RIDGE AXIS
TO SLOWLY MOVE INTO CENTRAL KANSAS DURING THE DAY THEN TOWARD
EASTERN KANSAS AS THE LOW PRESSURE SYSTEM SLOWLY MOVES EAST.
GFS/GEM MODELS HAVE THE LOW OVER SOUTHWEST ARIZONA BY DAYS THEN
INTO NEW MEXICO OVERNIGHT WHILE THE ECMWF HAS IT OVER NORTHERN
UTAH THEN WYOMING. SOME MID AND HIGH CLOUDS EXPECTED TO MOVE INTO
THE WESTERN 1/2 OF THE AREA DURING THE AFTERNOON WITH A PARTLY
CLOUDY SKY OVERNIGHT. A DRY FORECAST EXPECTED...HOWEVER GFS/ECMWF
850MB TEMPERATURES WARM ABOUT 5C FROM FRIDAYS READINGS SUPPORTING
HIGH TEMPERATURES IN THE MID 70S TO LOW 80S...POSSIBLY HIGHER IF
MEX GUIDANCE IS CORRECT. LOW TEMPERATURES IN THE MID 40S TO NEAR
50 FOR FAR EASTERN COLORADO...LOW TO MID 50S ELSEWHERE.
SUNDAY-SUNDAY NIGHT...APPEARS THE EXTENDED FORECAST PROCEDURE IS
LATCHING ON TO THE GFS/GEM MODELS WHICH MOVE THE UPPER LOW INTO
SOUTH CENTRAL COLORADO DURING THE DAY THEN SOUTHWEST KANSAS
OVERNIGHT. HAVE SOME SLIGHT CHANCE POPS ADVERTISED DURING THE DAY
INCREASING A TAD DURING THE NIGHT. AFTERNOON TEMPERATURES REMAIN
WARM WITH LOW TO UPPER 70S WITH OVERNIGHT LOWS IN THE LOW 40S TO
LOW 50S (WEST TO EAST ACROSS THE AREA).
MONDAY-MONDAY NIGHT...FORECAST WEIGHTED TOWARD THE GFS. UPPER LOW
FORECAST TO LIFT INTO NORTHEAST KANSAS BY THE END OF THE DAY THEN
SLOWLY NORTHEAST WHILE ANOTHER UPPER LOW IS FORECAST TO SPIN ITS
WAY SLOWLY SOUTH OVER THE PACIFIC NORTHWEST. NORTHERLY WINDS
EXPECTED WHICH WILL COOL AFTERNOON TEMPERATURES INTO THE UPPER 60S
TO LOW 70S UNDER A MOSTLY CLOUDY SKY. WILL HAVE SOME LOW CHANCE
POPS AS WELL FOR THUNDERSTORMS. QUITE A BIT OF CLOUDINESS
CONTINUES OVERNIGHT WITH LOWS IN THE LOW TO MID 40S AND A
CONTINUED SMALL CHANCE FOR LIGHT RAIN/RAIN SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 523 AM MDT TUE APR 19 2016
SHOWERS CURRENTLY OVER KGLD WILL CONTINUE TO SPREAD NORTHEAST OVER
KMCK WITHIN THE FIRST FEW HOURS OF THE TAF PERIOD. CURRENT TRENDS
SUPPORT MAINLY RAIN AT BOTH TERMINALS...THOUGH I STILL COULDNT
RULE OUT A MIX WITH SNOW DURING THE EARLY TAF PERIOD AT KGLD. THE
COMBINATION OF SHOWERS AND LINGERING LOW LEVEL MOISTURE WILL LEAD
TO AT LEAST PERIODS OF MVFR CONDITIONS AT KGLD (LESS LIKELY AT
KMCK). BASED ON RADAR/SATELLITE AND LATEST SHORT RANGE
GUIDANCE...MAIN AREA OF PRECIP SHOULD BE IN THE MORNING WITH
COVERAGE DECREASING IN THE AFTERNOON. I COULD STILL SEE A FEW
ISOLATED SHOWERS TONIGHT...HOWEVER CONFIDENCE IS LOW THAT ANYTHING
WOULD BE LINGERING WITHIN THE VICINITY OF EITHER TERMINAL.
WITH SURFACE HIGH PRESSURE IN PLACE...LIGHT WINDS...AND AMPLE LOW
LEVEL MOISTURE THERE IS A POSSIBILITY FOR FOG AND LOW STRATUS
DEVELOPMENT AROUND 06Z NEAR THE COLORADO STATE LINE. IFR
CONDITIONS ARE CURRENTLY MOST LIKELY AT KGLD WITH AT LEAST MVFR
AT KMCK. I TRENDED TAFS DOWN AT BOTH TERMINALS...BUT HELD OFF ON
INTRODUCING LIFR CONDITIONS DURING THIS UPDATE. THERE IS JUST TOO
MUCH UNCERTAINTY ON WHERE/EXTENT OF ANY SUB IFR CONDITIONS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
232 AM MDT TUE APR 19 2016
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
EARLY MORNING WV IMAGERY SHOWS LARGE UPPER LOW CENTERED NEAR THE
CO/WY WHICH EXTENDS ACROSS THE CENTRAL ROCKIES AND PLAINS. WV
IMAGERY SHOWS EMBEDDED SHORTWAVE ROTATING AROUND THE CENTER IN
EASTERN COLORADO. RAP SHOWS A STRONG PV 1.5 HEIGHT ANOMALY IN
EASTERN COLORADO HIGHLIGHTING TROPOPAUSE FOLD/STRONG SUBSIDENT
REGION BUILDING INTO SOUTHEAST COLORADO.
THIS MORNING-TODAY...INITIAL FORECAST CONCERN IS ON PRECIP TYPE
AND AMOUNTS. SURFACE TEMPERATURES AND RAP WET BULB TEMPS VARY
WILDLY AND PRECIP TYPE MAY END UP BEING MUCH MORE DYNAMIC THAN
PREVIOUSLY THOUGHT AS POCKETS OF WARMER TEMPERATURES HAVE ADVECTED
NORTHWARD...WHILE MODERATE PRECIP BANDS HAVE COOLED TEMP PROFILES
IN SOME LOCATIONS TO SUPPORT RAIN/SNOW MIX (POSSIBLE COMPLETE
CHANGE OVER). RESULT HAS BEEN MAINLY RAIN...WITH A FEW LOCATIONS
CHANGING OVER BRIEFLY.
FROM A SNOWFALL PERSPECTIVE...WEBCAMS IN REGIONS OF EASTERN
COLORADO THAT HAVE RECEIVED SNOW ONLY SHOW LIGHT PRECIP
ACCUMULATIONS IN GRASS...WITH WARM ROAD SURFACES REMAINING WET. IF
COMPLETE CHANGE OVER TO SNOW OCCURS IN OUR WESTERN CWA WE COULD
SEE AN INCH OR TWO...HOWEVER CONFIDENCE IS LOW THAT WE WOULD SEE
THIS IN ALL BUT A FEW ISOLATED LOCATIONS...AND WARM GROUND
TEMPERATURES ARE GOING TO DO A LOT TO LIMIT THE IMPACTS.
TREND IN LATEST GUIDANCE HAS BEEN TO DOWNPLAY QPF AMOUNTS SLIGHTLY
THROUGH THE MORNING HOURS...WHILE SPEEDING UP EXIT OF PRECIP FROM
THE WEST TO THE EAST IN THE 15-21Z TIME PERIOD. CONSIDERING THE
STRONG REGION OF SUBSIDENCE AND DRYING MID LEVELS ASSOCIATED WITH
TROPOPAUSE FOLD THIS PROGRESSIVE TREND SEEMS REASONABLE. HIGH POPS
ARE STILL REASONABLE...BUT I ADJUSTED TIMING FOR THE LATER PART OF
THE DAY TO SPEED UP DROP OFF IN PRECIP COVERAGE. DESPITE PRECIP
ENDING SOONER LINGERING LOW LEVEL CLOUD COVER WOULD LIKELY LIMIT
DAYTIME LAPSE RATES...AND CONFIDENCE IN THUNDERSTORM DEVELOPMENT
IS LOW. IF THERE IS ANY CLEARING WE COULD SEE A FEW WEAK
THUNDERSTORMS DEVELOP. THIS CLEARING WOULD BE ALSO BE NECESSARY
FOR ANY NON SUPERCELL TORNADO THREAT (VERY LOW CONFIDENCE AT THIS
TIME).
TONIGHT-WEDNESDAY NIGHT...OUR CWA SHOULD BE BETWEEN EMBEDDED
SHORTWAVE TROUGHS/VORT MAXES WITH PRECIP DIMINISHING OVERNIGHT
BEFORE NEXT SHORTWAVE TROUGH/REGION OF UPPER LEVEL DIVERGENCE
MOVES INTO THE REGION FROM THE NORTHWEST WEDNESDAY ON BACK SIDE
OF UPPER LOW (AS IT TRANSITIONS EAST). DURING THE NIGHT TONIGHT WE
COULD SEE A PERIOD OF FOG DEVELOP BEHIND INITIAL SHORTWAVE TROUGH
AS SURFACE HIGH PRESSURE STRENGTHENS ALONG CO/KS BORDER. THERE
SHOULD BE A LULL IN PRECIP BEFORE INCREASING CHANCES DURING THE
DAY. MODELS SHOW A LITTLE BIT BETTER INSTABILITY.
THURSDAY-THURSDAY NIGHT...SHORTWAVE RIDGING WILL BE IN PLACE
DURING THESE PERIODS WITH DRY CONDITIONS AND WARMER HIGH
TEMPERATURES (UPPER 60S/AROUND 70).
.LONG TERM...(FRIDAY THROUGH MONDAY NIGHT)
ISSUED AT 232 AM MDT TUE APR 19 2016
FRIDAY-FRIDAY NIGHT...ELONGATED UPPER RIDGE AXIS EXTENDING FROM
PARTS OF ALASKA SOUTH ALONG THE CONTINENTAL DIVE INTO MEXICO
DRIFTS EVER SO SLOWLY EAST THROUGH THE PERIOD AS A LOW PRESSURE
SYSTEM MOVES INTO SOUTHERN CALIFORNIA. LITTLE IF ANY CLOUDINESS
DURING THE DAY WITH SOUTH WINDS AROUND 15 MPH AND AFTERNOON
TEMPERATURES IN THE LOW TO MID 70S. A FEW HIGH CLOUDS MAY MOVE IN
FROM THE WEST DURING THE NIGHT WITH LOW TEMPERATURES RANGING FROM
THE LOW TO MID 40S IN FAR EASTERN COLORADO...MID 40S TO AROUND 50
ELSEWHERE. NO PRECIPITATION EXPECTED.
SATURDAY-SATURDAY NIGHT...GENERAL IDEA IS FOR THE UPPER RIDGE AXIS
TO SLOWLY MOVE INTO CENTRAL KANSAS DURING THE DAY THEN TOWARD
EASTERN KANSAS AS THE LOW PRESSURE SYSTEM SLOWLY MOVES EAST.
GFS/GEM MODELS HAVE THE LOW OVER SOUTHWEST ARIZONA BY DAYS THEN
INTO NEW MEXICO OVERNIGHT WHILE THE ECMWF HAS IT OVER NORTHERN
UTAH THEN WYOMING. SOME MID AND HIGH CLOUDS EXPECTED TO MOVE INTO
THE WESTERN 1/2 OF THE AREA DURING THE AFTERNOON WITH A PARTLY
CLOUDY SKY OVERNIGHT. A DRY FORECAST EXPECTED...HOWEVER GFS/ECMWF
850MB TEMPERATURES WARM ABOUT 5C FROM FRIDAYS READINGS SUPPORTING
HIGH TEMPERATURES IN THE MID 70S TO LOW 80S...POSSIBLY HIGHER IF
MEX GUIDANCE IS CORRECT. LOW TEMPERATURES IN THE MID 40S TO NEAR
50 FOR FAR EASTERN COLORADO...LOW TO MID 50S ELSEWHERE.
SUNDAY-SUNDAY NIGHT...APPEARS THE EXTENDED FORECAST PROCEDURE IS
LATCHING ON TO THE GFS/GEM MODELS WHICH MOVE THE UPPER LOW INTO
SOUTH CENTRAL COLORADO DURING THE DAY THEN SOUTHWEST KANSAS
OVERNIGHT. HAVE SOME SLIGHT CHANCE POPS ADVERTISED DURING THE DAY
INCREASING A TAD DURING THE NIGHT. AFTERNOON TEMPERATURES REMAIN
WARM WITH LOW TO UPPER 70S WITH OVERNIGHT LOWS IN THE LOW 40S TO
LOW 50S (WEST TO EAST ACROSS THE AREA).
MONDAY-MONDAY NIGHT...FORECAST WEIGHTED TOWARD THE GFS. UPPER LOW
FORECAST TO LIFT INTO NORTHEAST KANSAS BY THE END OF THE DAY THEN
SLOWLY NORTHEAST WHILE ANOTHER UPPER LOW IS FORECAST TO SPIN ITS
WAY SLOWLY SOUTH OVER THE PACIFIC NORTHWEST. NORTHERLY WINDS
EXPECTED WHICH WILL COOL AFTERNOON TEMPERATURES INTO THE UPPER 60S
TO LOW 70S UNDER A MOSTLY CLOUDY SKY. WILL HAVE SOME LOW CHANCE
POPS AS WELL FOR THUNDERSTORMS. QUITE A BIT OF CLOUDINESS
CONTINUES OVERNIGHT WITH LOWS IN THE LOW TO MID 40S AND A
CONTINUED SMALL CHANCE FOR LIGHT RAIN/RAIN SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1128 PM MDT MON APR 18 2016
VFR TO IFR CONDITIONS FORECAST FOR THE TAFS. MODELS HAVE SLOWED
DOWN THE ARRIVAL OF THE RAINFALL. WOULD NOT BE SURPRISED IF THE
RAINFALL COMES AN HOUR OR SO LATER THAN CURRENTLY FORECAST BASED
ON THE SLOWER TREND OVER THE LAST DAY OR SO. CEILING AT KPUB FELL
TO IFR WHEN THE PRECIPITATION MOVED OVERHEAD. BASED ON THAT EXPECT
THE SAME TREND FOR KGLD. KMCK MAY NOT FALL AS LOW DUE TO THE
PRECIPITATION WEAKENING AS IT APPROACHES THE SITE. KGLD WILL HAVE
VISIBILITY REDUCTIONS DUE TO THE MODERATE RAINFALL AND THE BRIEF
DURATION OF SNOW. THE BAND OF PRECIPITATION WILL MOVE NORTHEAST
WITH CONDITIONS IMPROVING AT KGLD FIRST IN THE AFTERNOON...THEN
KMCK DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...JTL
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1142 PM CDT MON APR 18 2016
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 309 PM CDT MON APR 18 2016
A shortwave continues to lift through northeast KS per the 20Z water
vapor imagery. Meanwhile the cut off upper low remains over
northwest CO. Surface obs indicate the trough axis is just to the
east of the forecast area with some drier and cooler air advecting
in from the northwest.
Subsidence from the shortwave is expected to keep the weather dry
over the forecast area for tonight. The main concern is whether some
fog develops. This is highly dependent on whether skies clear out
and the boundary layer radiates outs. Latest visible satellite
continues to show expansive stratocu deck across western KS and the
18Z RAP has trended towards keeping a stratus deck over the forecast
area through the night. Since the HRRR/RAP/SREF show visibilities
remaining at 5 miles or better, will keep the mention of patchy fog
across north central KS inserted by the prev shift since some breaks
in the clouds are possible, but will not expand it and any further.
Later shifts will need to watch the cloud trends for clearing. Then
the potential for fog ,even dense fog, would increase. Have not made
many changes to the low temp forecast as models continue to support
readings from the mid 40s across north central KS to the lower 50s
in east central KS as a result of some weak cold air advection.
For Tuesday, models show the potential for another shortwave to
round the bottom of the cut off low and lift north. As it does,
there is some modest moisture return as 850 winds veer around more
to the southeast. So with the prospects for increasing large scale
forcing, chances for precip increase through the afternoon from
south to north. Models show very modest instability developing given
mid level lapse rates remaining around 6 C/km. The GFS is most
aggressive in developing some instability across east central KS
tomorrow afternoon, but it also tries to break out the sun and heat
things up a little more. So while some thunderstorms cannot be ruled
out, think rain showers are most likely. Models do not show any warm
air advection and feel like clouds are going to be hard to scour
out. With this in mind, have afternoon highs in the mid and upper
60s.
.LONG TERM...(Tuesday Night through Monday)
Issued at 309 PM CDT MON APR 18 2016
Models are trending to a stronger wave rotating around the upper low
Tuesday night into Wednesday, with good forcing aloft interacting
with increasing moisture for another likely moderate, fairly
widespread rain event. It again appears to occur in the late Tuesday
night to Wednesday morning hours but a lack of consistent training
and instability still weak at best should keep amounts from being
troublesome. May have some clearing in the afternoon for temps to
push into the middle to upper 60s but this could be a challenge
depending on precip and temp timing. Not expecting much chance for
fog development WEdnesday night with northwest winds increasing
behind a weak surface trough and some high cloud remaining. The
northwest winds will not be able to bring in much air in this
stagnant pattern and warmer temps are anticipated for Thursday. Will
need to maintain some small pops for most areas through early
Thursday with the mean upper trough still upstream.
Longer range periods continue to show upper ridging in control of
the central CONUS into at least Saturday, but models become
increasingly into disagreement in handling of energy along nearly
the Pacific coast of much of North America. The 12Z ECMWF weakens
much of this energy, allowing for at least weak ridging aloft to
persist, allowing a front to sink south through the Northern Plains,
while the 12Z GFS and a few of its ensembles brings a shortwave on
east through the Southern Rockies over the weekend with a more
obviously wet and stormy scenario for late Sunday into Monday. With
many other GFS ensembles differing significantly, have kept precip
chances somewhat reduced compared to the GFS. Highs still look to
rise toward 80 for the weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1139 PM CDT MON APR 18 2016
MVFR ceilings are lasting longer than previously thought therefore
have extended them into the late morning. There is a chance if MHK
can clear out there will ground fog. Due to the uncertainty of
this clearing have kept it as a tempo group for now. The ceilings
may lift above MVFR tomorrow around mid day.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
104 PM CDT TUE APR 19 2016
.DISCUSSION...
QUICK EARLY AFTERNOON UPDATE TO ALLOW FLASH FLOOD WATCH TO EXPIRE
AS SCHEDULED.
13
&&
.PREV DISCUSSION... /ISSUED 1223 PM CDT TUE APR 19 2016/
DISCUSSION...
18Z TAFS.
AVIATION...
RADAR SHOWS MOST OF THE SHOWER AND THUNDERSTORM COVERAGE ACROSS SE
TEXAS THIS MORNING. BASED ON HRRR AND MESOSCALE FORECAST
TRENDS...EXPECT CONVECTION TO INCREASE ACROSS SW LOUISIANA EARLY
THIS AFTERNOON AS AIRMASS REMAINS UNCAPPED. RAIN COVERAGE WILL
WILL INCREASE AS WELL OVER CENTRAL AND SOUTH CENTRAL LOUISIANA
THROUGH THE AFTERNOON. WILL END PRECIPITATION AROUND 03Z
EVERYWHERE. MVFR CIGS AND VISIBILITIES ARE EXPECTED THROUGH THE
REMAINDER OF THE DAY...THEN TRENDING TOWARD IFR OVERNIGHT.
PREV DISCUSSION... /ISSUED 1136 AM CDT TUE APR 19 2016/
DISCUSSION...
MUCH QUIETER ACROSS THE AREA THIS MORNING VS 24 HRS AGO...WITH
ISOLATED TO SCATTERED SHOWERS DEVELOPING OVER EAST TX/WRN LA AS
OPPOSED TO WELL ORGANIZED AND WIDESPREAD CONVECTION. FLASH FLOOD
WATCH REMAINS IN EFFECT FOR ANOTHER 90 MINUTES...AND WILL TAKE
THAT TIME TO MONITOR ONGOING RADAR TRENDS AS WELL AS INCOMING
GUIDANCE FOR RAINFALL POTENTIAL THE REST OF TODAY AND TOMORROW.
CURRENT THINKING IS THAT WITH CONVECTION REMAINING DISORGANIZED
AND POSING A MORE ISOLATED AND LOCAL HEAVY RAIN RISK TODAY...WE
WILL ALLOW THE WATCH TO EXPIRE AS SCHEDULED.
FORECAST IS GENERALLY ON TARGET...WITH ONLY MINOR ADJUSTMENTS TO
FIRST PERIOD GRIDS.
13
PREV DISCUSSION... /ISSUED 459 AM CDT TUE APR 19 2016/
DISCUSSION...
STORMS YESTERDAY PRODUCED FOUR TO SIX INCHES OF RAINS WITH
FLOODING ACROSS COUNTIES IN SOUTHEAST TEXAS AND SOUTHWEST
LOUISIANA... SEVEN RIVER FORECAST SITES ARE NOW CURRENTLY IN
FLOOD WITH A MAJORITY OF THE LOCATIONS IN SE TX.
THIS MORNING IS STARTING OUT A BIT MORE QUIET AS THE RADAR IS
INDICATING ONLY A FEW SHOWERS ON RADAR... THESE STORMS ARE
LIFTING TO THE NORTH. WHAT LOOKS TO BE HAPPENING IS THE ATMOSPHERE
IS TAKING A BREATHER BEFORE THE NEXT ROUND. CURRENTLY TEMPERATURES
ARE RANGING FROM THE MID 60S INLAND TO NEAR 70 TOWARDS THE
COAST ON LIGHT SOUTHEAST WINDS.
THE UPPER LEVEL LOW THAT HAS BEEN SUPPORTING STORMS STILL REMAINS
BACK TO THE NORTHWEST. ADDITIONAL SHORTWAVES ARE EXPECTED TO
ADVECT UNDER THE SYSTEM AND WILL MOVE ACROSS THE REGION TODAY.
THIS WILL MEAN ANOTHER ROUND OF STORMS DEVELOPING TOWARDS THE NOON
HOUR AND CONTINUING INTO THE AFTERNOON HOURS. TEMPERATURES TO
MODERATE FROM CLOUDS AND RAINS.
WE ARE CURRENTLY IN A PERSISTENT PATTERN THAT IS EXPECTED TO HOLD
THROUGH THURSDAY... FINALLY DRAWING TO A CLOSE EARLY FRIDAY
MORNING AS THE LOW MOVES EAST AND NORTHEAST OF THE REGION WITH
SINKING AIR BECOMING ESTABLISHED ALOFT.
THE REGION HAS BEEN COMPLETELY SATURATED FROM RAINS... ADDITIONAL
RAINS ARE EXPECTED TO RUNOFF INTO DITCHES AND BAYOUS WITH MORE
RIVER FLOODING ANTICIPATED OVER THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 76 63 76 65 / 70 50 70 60
LCH 76 68 77 68 / 70 40 50 40
LFT 78 67 80 68 / 50 40 40 40
BPT 77 68 78 68 / 70 40 60 40
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1109 PM CDT MON APR 18 2016
.UPDATE...
CONVECTION HAS BEEN SLOWLY DIMINISHING IN ASSOCIATION WITH AN MCV
OVER THE COASTAL WATERS THIS EVENING. THIS ACTIVITY EARLIER
EXTENDED IN A LINE ACRS SW LA INTO CNTL LA. AS THESE STORMS
WEAKENED AND COLLAPSED...THEY PRODUCED STRONG AND GUSTY WINDS
ACRS THE COASTAL WATERS AND SW LA FOR A FEW HOURS...EVEN SPREADING
BRIEFLY INTO SE TX BEFORE FINALLY DIMINISHING...AND PROMPTED THE
ISSUANCE OF A COUPLE OF SPECIAL WEATHER STATEMENTS AND SPECIAL
MARINE WARNINGS. A FEW OF THE MEASURED PEAK WINDS INCLUDE 44 MPH
AT SOUTHLAND FIELD IN CARLYSS...46 MPH AT LAKE CHARLES REGIONAL
AIRPORT...AND A 45 KT (52 MPH) WIND GUST AT KVBS AWOS 20 MILES
SOUTH OF JOHNSONS BAYOU.
OTHERWISE...ACTIVITY HAS DIMINISHED ACRS THE AREA THIS EVENING BUT
RECENT RADAR TRENDS INDICATE SHOWERS RE-DEVELOPING ACRS SE TX AND
WRN LA. HI-RES GUIDANCE CONTINUES TO INDICATE SHOWERS AND A FEW
STORMS WILL BECOMING MORE NMRS THROUGH THE NIGHT ACRS THIS
AREA...AND WITH ABUNDANT MOISTURE OVER THE AREA...SOME STORMS WILL
BE CAPABLE OF PRODUCING HEAVY RAINFALL. RECENT MRMS BIAS CORRECTED
RAINFALL ESTIMATES INDICATE 2 TO 6 INCHES OF RAIN FELL ACRS SE TX
AND EXTREME SW LA TODAY WITH LOCALLY HIGHER AMOUNTS UP TO AROUND 8
INCHES. WITH OVERNIGHT CONVECTION EXPECTED TO PERSIST INTO THE
DAY TUESDAY...WENT AHEAD AND EXTENDED THE FLASH FLOOD WATCH
THROUGH 18Z TUESDAY.
ADJUSTED HOURLY WINDS THIS EVENING TO REFLECT OBS AND TRENDS AND
ALSO FINE TUNED POPS AS WELL. REMAINDER OF FCST LOOKS FINE.
24
&&
.PREV DISCUSSION... /ISSUED 542 PM CDT MON APR 18 2016/
DISCUSSION...
00Z TAF ISSUANCE.
AVIATION...
COMPLEX OF SHRA/TSRA OVER W LA FROM POE TO LCH AND CAMERON
EXTENDING OFFSHORE...MOVING EAST AT ~10 MPH. THUS...PREVAILING
SHRA/TSRA AND MVFR CEILINGS EXPECTED AT LCH...AND AT AEX SHORTLY
AS IT ARRIVES. FOR BPT...HEAVIEST CONVECTION OUT OF SE TX...WITH
ONLY INTERMITTENT SHRA EXPECTED THIS EVENING AND OVERNIGHT...BUT
MVFR TO IFR CEILINGS EXPECTED. AT LFT/ARA...LEFT TEMPO GROUP FOR
INTERMITTENT SHRA AS THIS COMPLEX MOVES FURTHER EAST...BUT BELIEVE
IT WILL CONTINUE WEAKENING AND BE CLOSE TO DISSIPATION BY THE TIME
IT ARRIVES OVER ACADIANA. OTHERWISE...MVFR TO IFR CEILINGS
EXPECTED AT REMAINING SITES OVERNIGHT INTO TUE MORNING.
FOR LATE TUE MORNING INTO THE AFTERNOON...ANOTHER ROUND OF
SHRA/TSRA EXPECTED TO FORM OVER SE TX/W LA BY LATE MORNING INTO
THE AFTERNOON HOURS AND SPREAD EAST AS WELL. PLACED PROB30 GROUP
FROM 18-24Z FOR TSRA & IFR VSBY/CEILINGS.
PREV DISCUSSION... /ISSUED 453 PM CDT MON APR 18 2016/
DISCUSSION...
IN TERMS OF THE OVERALL PATTERN EVOLUTION...LITTLE HAS CHANGED
SINCE YESTERDAY...WITH AN UPPER LOW/TROF OVER THE ROCKIES FCST TO
SLOWLY TRANSLATE EWD AS THE DOWNSTREAM RIDGE OVER THE ERN CONUS
BREAKS DOWN...EVENTUALLY SENDING A CDFNT THROUGH THE REGION LATE
THU INTO FRIDAY. UNTIL THEN...A SOUTHERLY MOIST LOW LEVEL INFLOW
ALONG WITH PERIODIC IMPULSES EJECTING DOWNSTREAM OF THE UPPER LOW
WILL AID IN GENERATING CLUSTERS OF SHOWERS AND THUNDERSTORMS.
FOR THE REST OF TODAY AND INTO TONIGHT...CURRENT N-S ORIENTED
COMPLEX OF CONVECTION IS PROGGED TO CONTINUE SLOWLY EWD...WITH THE
MODEL GUIDANCE THAT ACTUALLY DEPICTS IT INDICATING WEAKENING AND
DISSIPATION AS IT REACHES INTO EAST/SOUTH CENTRAL LOUISIANA. THE
EXPERIMENTAL HRRR APPEARS TO HAVE CAPTURED THIS CONVECTION THE
BEST...AND IS IN LINE WITH THIS SCENARIO. IT SHOWS A GENERAL 1 TO
2 INCH SWATH OF RAIN GENERALLY WITHIN A REGION BOUNDED BY THE
CURRENT WESTERN EDGE OF THE CONVECTION TO ROUGHLY AN ALEXANDRIA TO
LAKE ARTHUR LINE...WITH AMOUNTS TAPERING OF QUICKLY TO AROUND A
TENTH OF AN INCH OR LESS EAST OF A MARKSVILLE TO LAFAYETTE LINE.
VERY LITTLE ADDITIONAL RAINFALL IS FORECAST OVER EAST TEXAS THE
REST OF THE AFTERNOON AND EVENING...THOUGH INDICATIONS IN THIS AND
OTHER GUIDANCE POINT TO NEW CONVECTIVE DEVELOPMENT OVER EAST TX
AND WESTERN LA DURING THE OVERNIGHT HRS TWD TUE MORNING. MSTR
CONTENT IS PROGGED TO REMAIN QUITE HIGH...MEANING ANY CONVECTION
THAT DEVELOPS WILL BE CAPABLE OF HIGH RAINFALL RATES...AND WILL
ALSO BE FALLING OVER AREAS THAT RECEIVED ANYWHERE FROM 2 TO
UPWARDS OF 6 INCHES OF RAIN TODAY. THUS...EVEN THOUGH NOT MUCH
RAIN IS EXPECTED IN THE WATCH AREA FOR A PERIOD OF TIME AFTER THE
CURRENT ACTIVITY MOVES OFF TO THE EAST...OPTED TO LEAVE THE FLOOD
WATCH IN PLACE THROUGH THE CURRENT 7AM TUE EXPIRATION TIME.
PENDING THE DEVELOPMENT OF THIS ADDITIONAL RAINFALL...THE WATCH
WILL EITHER BE CANCELLED OR EXTENDED IN TIME LATER SHIFTS.
FCST BEYOND THIS TIME BECOMES MORE UNCERTAIN...BUT IT APPEARS THAT
ANOTHER ROUND OF RAIN WILL MOVE THROUGH THE AREA ON WED AS ONE OF
THE AFOREMENTIONED IMPULSES TRAVERSES THE REGION...WITH YET MORE
RAIN ON THURSDAY AS THE CDFNT SAGS INTO THE GULF COAST STATES.
SOME LINGERING RAIN IS POSSIBLE ON FRIDAY...BUT AT LEAST THE START
OF THE WEEKEND LOOKS DRY WITH RIDGING BUILDING IN BEHIND THE
DEPARTING TROF.
13
MARINE...
LOW PRESSURE TO THE NORTHWEST AND HIGH PRESSURE TO THE EAST WILL
KEEP THE NORTHWEST GULF OF MEXICO IN A LONG FETCH OF ONSHORE
WINDS. ELEVATED WINDS WILL CONTINUE THIS EVENING...BUT BEGIN TO
SUBSIDE DURING THE OVERNIGHT PERIOD. ADDITIONALLY...SHOWER AND
THUNDERSTORM ACTIVITY WILL CONTINUE TO BE POSSIBLE AS DEEPENING
MOISTURE COMBINES WITH AN AREA OF LOW PRESSURE ALOFT OVER THE
SOUTHERN ROCKIES AND HIGH PLAINS.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 63 76 64 79 / 70 70 50 50
LCH 69 77 68 79 / 70 70 40 50
LFT 67 78 67 80 / 40 40 30 40
BPT 68 77 68 79 / 60 90 40 50
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR LAZ027-030-041-
073.
COASTAL FLOOD WARNING UNTIL 7 AM CDT TUESDAY FOR LAZ041.
COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR LAZ052>054-073-
074.
TX...FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR TXZ180-201-215-
216-259>262.
COASTAL FLOOD WARNING UNTIL 7 AM CDT TUESDAY FOR TXZ216.
COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR TXZ215.
GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR GMZ470-472-475.
SMALL CRAFT EXERCISE CAUTION UNTIL 7 AM CDT TUESDAY FOR GMZ450-
452-455.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1055 PM EDT WED APR 20 2016
.SYNOPSIS...
HIGH PRESSURE OVER NEW YORK STATE WILL MOVE INTO THE MID ATLANTIC
TONIGHT BEFORE SLIDING OFFSHORE THURSDAY. A COLD FRONT WILL MOVE
THROUGH THE REGION FRIDAY. HIGH PRESSURE RETURNS FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
HIGH PRESSURE CONTINUES TO SLIDE EAST-SOUTHEAST AWAY FROM THE AREA
THIS EVENING. HIGH CLOUDS WILL START TO INCREASE OVERNIGHT AS THE
SYSTEM TO THE WEST APPROACHES BUT SHOULD STAY CLEAR ENOUGH TO
ALLOW RADIATIONAL COOLING AWAY FROM THE CITIES. THE DECOUPLING
SHOULD ALSO ALLOW SMOKE AROUND THE ROCKY MOUNT FIRE TO SETTLE
IN THE SURROUNDING VALLEYS...PARTICULARLY TO THE NORTH OF THE FIRE
SINCE WINDS HAVE SHIFTED DEFINITIVELY SOUTH. HAVE INCLUDED AREAS
OF SMOKE FOR THIS AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
HIGH PRES MOVES OFFSHORE THU. TEMPS WL BE A FEW DEGS WARMER THAN
TDA - HIGHS IN THE LM70S. THU NGT WL BE WARMER W/ LOWS IN THE
MU50S.
AS THE CD FNT DRAWS CLOSER TO THE RGN THERE WL FINALLY BE CHCS FOR
PCPN LATE THU NGT. BUT THE BEST CHC FOR RAIN WL BE ON FRI AS WELL
AS THE PSBLTY OF SOME TSTM ACTVTY. ATTM QPF LOOKS TO BE ARND 1/2
INCH. HOW MUCH IMPACT THIS WL HV ON THE ROCKINGHAM FIRE TIME WL
TELL.
IF THE RAIN DOES NOT HV MUCH OF AN IMPACT ON THE FIRE SAT COULD
BECOME A PRBLM AS HIGH PRES BLDS BACK INTO THE RGN AND WINDS
BECOME GUSTY. HIGHS AGN IN U60S/L70S.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
HIGH PRES MOVES OFF OF THE MID-ATLANTIC COAST ON SUN AND DRY
CONDITIONS CONTINUE INTO EARLY MON. COLD FRONT APPROACHES FROM THE
NORTH ON MON AND BECOMES STATIONARY OVER OUR REGION INTO TUE.
PRECIP EXPECTED TO ARRIVE FROM THE NW ON MON AND REMAIN INTO TUE
AS FRONT SLOWLY PUSHES SOUTH TUE INTO WED.
WED CONDITIONS ARE MORE UNCERTAIN. GUIDANCE SUGGEST EITHER THAT A
LOW PRESS WILL MOVE FROM THE PLAINS AND ACROSS OUR REGION BRINGING
ADDITIONAL PRECIP...OR THAT A WEAK HIGH PRES SYSTEM WILL BUILDS
ACROSS AND KEEPS THE AREA MOSTLY DRY.
TEMPS WILL BE NEAR OR ABOVE NORMAL DURING THIS PERIOD... WITH HIGH
TEMPS IN THE 60S AND 70S AND LOW TEMPS IN THE 40S AND 50S.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
VFR CONDS THRU THU NGT. A CD FNT CROSSING THE RGN FRI WL BRING
SHRA/ISOLD CNVCTN/PTNL FOR SUB VFR CIGS. VFR RETURNS FRI NGT THRU
SAT NGT AS HIGH PRES RETURNS.
VFR CONDITIONS EXPECTED ON SUN WITH HIGH PRES DOMINATING THE
WEATHER CONDITIONS OVER OUR REGION. SUB-VFR CONDITIONS POSSIBLE
ON MON AND TUE AS COLD FRONT APPROACHES AND LINGERS OVER OUR
REGION BRINGING A CHANCE OF SHOWERS.
&&
.MARINE...
MINOR SOUTHERLY CHANNELING HAS BROUGHT SCA CONDITIONS ACROSS MUCH
OF THE BAY TONIGHT AND HAVE ISSUED SCA TO COVER THROUGH TOMORROW
MORNING. HRRR IS MODELING THIS BEST AND IT KEEPS THE WINDS GOING
THRU THE NIGHT. MAY BE A LULL IN THE MORNING BEFORE SOUTHWEST
FLOW AHEAD OF THE APPROACHING FRONTAL SYSTEM KICKS IN. AS
MENTIONED EARLIER...THIS SOUTHWEST FLOW LOOKS A BIT STRONGER IN
THE LATEST GUIDANCE AND DECIDED TO PUT OUT AN SCA FOR TOMORROW
AFTERNOON AS WELL. BY TOMORROW AFTERNOON...THINK MOST GUSTS WILL
BE NEAR-SHORE GIVEN THE WARMER AIR OVER THE COOLER WATER SHOULD
LIMIT GUSTS OVER THE OPEN BAY. THESE WINDS MAY CONTINUE THURSDAY
NIGHT AND WILL LIKELY OCCUR AGAIN FRIDAY INTO FRIDAY NIGHT.
BEHIND FRONT...SCA GUSTS STILL LOOKING LIKE A GOOD BET SATURDAY
AS WELL ON THE COLD ADVECTION NORTHWEST FLOW.
SUB-SCA CONDITIONS EXPECTED FROM SUN INTO TUE AS WINDS WILL
REMAIN BELOW CRITERIA DURING THIS PERIOD.
&&
.TIDES/COASTAL FLOODING...
SOUTHERLY FLOW AND FULL MOON WORKING TO RAISE ANOMALIES ACROSS THE
TIDAL WATERS. LOOKING LIKE WE WILL BE CLOSE TO MINOR AT OUR
SENSITIVE SITES ON THURSDAY. WILL NEED TO CLOSELY MONITOR
POTENTIAL FOR COASTAL FLOOD ADVISORIES.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ531>534-
537-539>543.
SMALL CRAFT ADVISORY FROM NOON TO 6 PM EDT THURSDAY FOR ANZ530-
535-536-538.
&&
$$
PRODUCTS...WOODY!/IMR/RCM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
110 PM EDT TUE APR 19 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT TUE APR 19 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CO/WY AND RIDGING FROM SRN SASK/MANITOBA THROUGH NRN MN AND
WI...LEAVING NW FLOW THROUGH MOST OF NRN ONTARIO GRAZING THE NRN
LAKES. AT THE SFC...NE LOW LEVEL FLOW PREVAILED BETWEEN HIGH PRES
OVER NRN ONTARIO INTO LAKE SUPERIOR AND A TROUGH FROM NRN SD INTO NE
IA WITH A FRONT INTO THE WRN LAKES. PCPN ASSOCIATED WITH
FGEN/DEFORMATION NORTH OF THE FRONT LINGERED THROUGH THE UPPER MS
VALLEY AND ACROSS CNTRL WI TO NEAR GRB. OVER UPPER MI...UPSLOPE NE
FLOW HAS SUPPORTED SOME PATCHY FOG AND LOW CLOUDS OVER N CNTRL UPPER
MI. OTHERWISE...IR LOOP SHOWED MAINLY JUST MID/HIGH CLOUDS ACROSS
THE AREA...THICKEST OVER THE SOUTH.
MODELS SUGGEST THAT PCPN ASSOCIATED WITH THE MID LEVEL LOW EDGING
INTO THE PLAINS AND THE DEFORMATION ZONE LIFTING SLOWLY NE FROM THE
UPPER MS VALLEY WILL APPROACH UPPER MI. HOWEVER...GIVEN THE DRY ESE
LOW LEVEL FLOW FROM THE NRN ONTARIO HIGH AND RELATIVELY WEAK FORCING
AND MOISTURE INFLOW...EXPECT THE RAIN TO REMAIN TO THE SW OF THE
CWA.
LINGERING LOW CLOUDS OVER FAVORED UPSLOPE LOCATIONS NORTH SHOULD
DISSIPATE BY MID MORNING AS DAYTIME MIXING INCREASES. WITH 850 MB
TEMPS AROUND 6C...EXPECT ENOUGH SUNSHINE THROUGH THE HIGH CLOUDS TO
BOOST TEMPS INTO THE LOWER 60S INLAND. LAKE BREEZES WILL KEEP TEMPS
INTO THE UPPER 40S AND LOWER 50S ALONG THE GREAT LAKES. THICKER
CLOUDS AND INCREASING SRLY FLOW INTO W UPPER MI TONIGHT WILL HELP
KEEP TEMPS FROM FALLING OFF AS FAR WITH MIN READINGS INTO THE LOW TO
MID 40S. OTHERWISE...TEMPS SHOULD DROP INTO THE MID 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE APR 19 2016
AN UPPER LOW OVER THE PLAINS WED MORNING WILL BEGIN TO SHIFT TOWARD
THE AREA THROUGH WED AS AN UPPER TROUGH MOVES INTO CENTRAL CANADA.
WEAK FORCING MAY LEAD TO SOME LIGHT RAIN SHOWERS WED...BUT MODELS
HAVE TRENDED DRIER...SO DOUBT THE RAIN WILL BE ABLE TO SIGNIFICANTLY
OVERCOME THAT DRY AIR. WILL CONTINUE SLIGHT CHANCE POPS.
THE UPPER LOW GETS ABSORBED INTO THE UPPER TROUGH AS IS PASSES
THROUGH THE AREA ON WED NIGHT AND THU. BEST FORCING FOR WIDESPREAD
PRECIP LOOKS TO BE OVER THE SOUTHEASTERN CWA WITH MORE SCATTERED
COVERAGE ELSEWHERE. PRECIP SHOULD BE ALL RAIN...WITH DRIZZLE IN
UPSLOPE N WIND AREAS LATE THU INTO EARLY THU NIGHT. WITH DRY AIR
MOVING IN BEHIND THE SYSTEM...THINK THAT PRECIP WILL END BEFORE ANY
PTYPE CHANGE OCCURS.
FRI LOOKS DRY AS HIGH PRESSURE MOVES IN. THE COLDER AIR AND N WINDS
THAT MOVE IN WITH THE CANADIAN TROUGH WILL KEEP HIGH TEMPS ALONG
LAKE SUPERIOR AROUND 40 AND UP TO THE LOW 50S NEAR THE WI BORDER.
COULD SEE SOME WAA/ISENTROPIC ASCENT PRECIP LATE FRI INTO SAT...BUT
CONFIDENCE IS LOW GIVEN HIGHLY VARIABLE MODEL SOLUTIONS OVER THE
LAST COUPLE OF DAYS. WEEKEND TEMPS WILL BE SIMILAR TO FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 109 PM EDT TUE APR 19 2016
VFR CONDITIONS AND LIGHT WINDS ASSOCIATED WITH HIGH PRESSURE MOVING
THROUGH ONTARIO WILL PREDOMINATE FOR THE REST OF THE TAF PERIOD AT
ALL 3 SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT TUE APR 19 2016
WINDS LOOK TO STAY BELOW 25 KNOTS FOR THIS ENTIRE FORECAST PERIOD
WITH NO GALES EXPECTED. EXPECT HIGH PRESSURE TO BRINGS LIGHT WINDS
THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE
SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25
KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE
SETTLES TO THE NW. WINDS STAY LIGHT THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT TUE APR 19 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT TUE APR 19 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CO/WY AND RIDGING FROM SRN SASK/MANITOBA THROUGH NRN MN AND
WI...LEAVING NW FLOW THROUGH MOST OF NRN ONTARIO GRAZING THE NRN
LAKES. AT THE SFC...NE LOW LEVEL FLOW PREVAILED BETWEEN HIGH PRES
OVER NRN ONTARIO INTO LAKE SUPERIOR AND A TROUGH FROM NRN SD INTO NE
IA WITH A FRONT INTO THE WRN LAKES. PCPN ASSOCIATED WITH
FGEN/DEFORMATION NORTH OF THE FRONT LINGERED THROUGH THE UPPER MS
VALLEY AND ACROSS CNTRL WI TO NEAR GRB. OVER UPPER MI...UPSLOPE NE
FLOW HAS SUPPORTED SOME PATCHY FOG AND LOW CLOUDS OVER N CNTRL UPPER
MI. OTHERWISE...IR LOOP SHOWED MAINLY JUST MID/HIGH CLOUDS ACROSS
THE AREA...THICKEST OVER THE SOUTH.
MODELS SUGGEST THAT PCPN ASSOCIATED WITH THE MID LEVEL LOW EDGING
INTO THE PLAINS AND THE DEFORMATION ZONE LIFTING SLOWLY NE FROM THE
UPPER MS VALLEY WILL APPROACH UPPER MI. HOWEVER...GIVEN THE DRY ESE
LOW LEVEL FLOW FROM THE NRN ONTARIO HIGH AND RELATIVELY WEAK FORCING
AND MOISTURE INFLOW...EXPECT THE RAIN TO REMAIN TO THE SW OF THE
CWA.
LINGERING LOW CLOUDS OVER FAVORED UPSLOPE LOCATIONS NORTH SHOULD
DISSIPATE BY MID MORNING AS DAYTIME MIXING INCREASES. WITH 850 MB
TEMPS AROUND 6C...EXPECT ENOUGH SUNSHINE THROUGH THE HIGH CLOUDS TO
BOOST TEMPS INTO THE LOWER 60S INLAND. LAKE BREEZES WILL KEEP TEMPS
INTO THE UPPER 40S AND LOWER 50S ALONG THE GREAT LAKES. THICKER
CLOUDS AND INCREASING SRLY FLOW INTO W UPPER MI TONIGHT WILL HELP
KEEP TEMPS FROM FALLING OFF AS FAR WITH MIN READINGS INTO THE LOW TO
MID 40S. OTHERWISE...TEMPS SHOULD DROP INTO THE MID 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE APR 19 2016
AN UPPER LOW OVER THE PLAINS WED MORNING WILL BEGIN TO SHIFT TOWARD
THE AREA THROUGH WED AS AN UPPER TROUGH MOVES INTO CENTRAL CANADA.
WEAK FORCING MAY LEAD TO SOME LIGHT RAIN SHOWERS WED...BUT MODELS
HAVE TRENDED DRIER...SO DOUBT THE RAIN WILL BE ABLE TO SIGNIFICANTLY
OVERCOME THAT DRY AIR. WILL CONTINUE SLIGHT CHANCE POPS.
THE UPPER LOW GETS ABSORBED INTO THE UPPER TROUGH AS IS PASSES
THROUGH THE AREA ON WED NIGHT AND THU. BEST FORCING FOR WIDESPREAD
PRECIP LOOKS TO BE OVER THE SOUTHEASTERN CWA WITH MORE SCATTERED
COVERAGE ELSEWHERE. PRECIP SHOULD BE ALL RAIN...WITH DRIZZLE IN
UPSLOPE N WIND AREAS LATE THU INTO EARLY THU NIGHT. WITH DRY AIR
MOVING IN BEHIND THE SYSTEM...THINK THAT PRECIP WILL END BEFORE ANY
PTYPE CHANGE OCCURS.
FRI LOOKS DRY AS HIGH PRESSURE MOVES IN. THE COLDER AIR AND N WINDS
THAT MOVE IN WITH THE CANADIAN TROUGH WILL KEEP HIGH TEMPS ALONG
LAKE SUPERIOR AROUND 40 AND UP TO THE LOW 50S NEAR THE WI BORDER.
COULD SEE SOME WAA/ISENTROPIC ASCENT PRECIP LATE FRI INTO SAT...BUT
CONFIDENCE IS LOW GIVEN HIGHLY VARIABLE MODEL SOLUTIONS OVER THE
LAST COUPLE OF DAYS. WEEKEND TEMPS WILL BE SIMILAR TO FRI.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 738 AM EDT TUE APR 19 2016
AS DAYTIME MIXING INCREASES BY MID MORNING...EXPECT LINGERING LOW
CLOUDS AND FOG AT CMX AND SAW TO BREAK UP AND GIVE WAY TO VFR WX.
THESE VFR CONDITIONS AND LIGHT WINDS ASSOCIATED WITH HIGH PRES
SLIDING SE THROUGH ONTARIO WILL THEN PREDOMINATE FOR THE REST OF THE
TAF PERIOD AT ALL 3 SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT TUE APR 19 2016
WINDS LOOK TO STAY BELOW 25 KNOTS FOR THIS ENTIRE FORECAST PERIOD
WITH NO GALES EXPECTED. EXPECT HIGH PRESSURE TO BRINGS LIGHT WINDS
THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE
SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25
KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE
SETTLES TO THE NW. WINDS STAY LIGHT THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EDT TUE APR 19 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT TUE APR 19 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CO/WY AND RIDGING FROM SRN SASK/MANITOBA THROUGH NRN MN AND
WI...LEAVING NW FLOW THROUGH MOST OF NRN ONTARIO GRAZING THE NRN
LAKES. AT THE SFC...NE LOW LEVEL FLOW PREVAILED BETWEEN HIGH PRES
OVER NRN ONTARIO INTO LAKE SUPERIOR AND A TROUGH FROM NRN SD INTO NE
IA WITH A FRONT INTO THE WRN LAKES. PCPN ASSOCIATED WITH
FGEN/DEFORMATION NORTH OF THE FRONT LINGERED THROUGH THE UPPER MS
VALLEY AND ACROSS CNTRL WI TO NEAR GRB. OVER UPPER MI...UPSLOPE NE
FLOW HAS SUPPORTED SOME PATCHY FOG AND LOW CLOUDS OVER N CNTRL UPPER
MI. OTHERWISE...IR LOOP SHOWED MAINLY JUST MID/HIGH CLOUDS ACROSS
THE AREA...THICKEST OVER THE SOUTH.
MODELS SUGGEST THAT PCPN ASSOCIATED WITH THE MID LEVEL LOW EDGING
INTO THE PLAINS AND THE DEFORMATION ZONE LIFTING SLOWLY NE FROM THE
UPPER MS VALLEY WILL APPROACH UPPER MI. HOWEVER...GIVEN THE DRY ESE
LOW LEVEL FLOW FROM THE NRN ONTARIO HIGH AND RELATIVELY WEAK FORCING
AND MOISTURE INFLOW...EXPECT THE RAIN TO REMAIN TO THE SW OF THE
CWA.
LINGERING LOW CLOUDS OVER FAVORED UPSLOPE LOCATIONS NORTH SHOULD
DISSIPATE BY MID MORNING AS DAYTIME MIXING INCREASES. WITH 850 MB
TEMPS AROUND 6C...EXPECT ENOUGH SUNSHINE THROUGH THE HIGH CLOUDS TO
BOOST TEMPS INTO THE LOWER 60S INLAND. LAKE BREEZES WILL KEEP TEMPS
INTO THE UPPER 40S AND LOWER 50S ALONG THE GREAT LAKES. THICKER
CLOUDS AND INCREASING SRLY FLOW INTO W UPPER MI TONIGHT WILL HELP
KEEP TEMPS FROM FALLING OFF AS FAR WITH MIN READINGS INTO THE LOW TO
MID 40S. OTHERWISE...TEMPS SHOULD DROP INTO THE MID 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE APR 19 2016
AN UPPER LOW OVER THE PLAINS WED MORNING WILL BEGIN TO SHIFT TOWARD
THE AREA THROUGH WED AS AN UPPER TROUGH MOVES INTO CENTRAL CANADA.
WEAK FORCING MAY LEAD TO SOME LIGHT RAIN SHOWERS WED...BUT MODELS
HAVE TRENDED DRIER...SO DOUBT THE RAIN WILL BE ABLE TO SIGNIFICANTLY
OVERCOME THAT DRY AIR. WILL CONTINUE SLIGHT CHANCE POPS.
THE UPPER LOW GETS ABSORBED INTO THE UPPER TROUGH AS IS PASSES
THROUGH THE AREA ON WED NIGHT AND THU. BEST FORCING FOR WIDESPREAD
PRECIP LOOKS TO BE OVER THE SOUTHEASTERN CWA WITH MORE SCATTERED
COVERAGE ELSEWHERE. PRECIP SHOULD BE ALL RAIN...WITH DRIZZLE IN
UPSLOPE N WIND AREAS LATE THU INTO EARLY THU NIGHT. WITH DRY AIR
MOVING IN BEHIND THE SYSTEM...THINK THAT PRECIP WILL END BEFORE ANY
PTYPE CHANGE OCCURS.
FRI LOOKS DRY AS HIGH PRESSURE MOVES IN. THE COLDER AIR AND N WINDS
THAT MOVE IN WITH THE CANADIAN TROUGH WILL KEEP HIGH TEMPS ALONG
LAKE SUPERIOR AROUND 40 AND UP TO THE LOW 50S NEAR THE WI BORDER.
COULD SEE SOME WAA/ISENTROPIC ASCENT PRECIP LATE FRI INTO SAT...BUT
CONFIDENCE IS LOW GIVEN HIGHLY VARIABLE MODEL SOLUTIONS OVER THE
LAST COUPLE OF DAYS. WEEKEND TEMPS WILL BE SIMILAR TO FRI.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 132 AM EDT TUE APR 19 2016
AS DRIER LLVL AIR ARRIVES EARLY THIS MRNG...EXPECT LINGERING LO CLDS
TO BREAK UP AND GIVE WAY TO VFR WX. THESE VFR CONDITIONS AND LIGHT
WINDS ASSOCIATED WITH HI PRES SLIDING SE THRU ONTARIO WL THEN
PREDOMINATE THE REST OF THE TAF PERIOD AT ALL 3 SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT TUE APR 19 2016
WINDS LOOK TO STAY BELOW 25 KNOTS FOR THIS ENTIRE FORECAST PERIOD
WITH NO GALES EXPECTED. EXPECT HIGH PRESSURE TO BRINGS LIGHT WINDS
THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE
SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25
KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE
SETTLES TO THE NW. WINDS STAY LIGHT THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS JACKSON MS
820 PM CDT WED APR 20 2016
.UPDATE...A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS EXTEND FROM
NEAR GRENADA TO JUST WEST OF JACKSON DOWN INTO NATCHEZ THIS MORNING
AND IS EVER SO SLOWLY MOVING TO THE EAST. HI-RES MODELS SUGGEST THIS
BAND OF SHOWERS WILL CONTINUE TO SLOWLY MOVE EASTWARD THROUGH THE
EVENING INTO THE OVERNIGHT HOURS AND SLOWLY DISSIPATE...WITH
ISOLATED SHOWERS POSSIBLE ACROSS THE AREA THROUGH THE NIGHT. EXPECT
THE ACTIVITY TO REMAIN BELOW STRONG TO SEVERE LIMITS AS THERE IS
VERY LITTLE INSTABILITY TO WORK WITH. MADE A FEW MINOR ADJUSTMENTS
TO THE FORECAST...BUT FOR THE MOST PART IS ON TRACK./15/
.DISCUSSION...A COLD FRONT CONTINUES TO PUSH SLOWLY TOWARD THE
REGION WITH THE BOUNDARY NOW BACK IN THE ARKLATEX AND HEADED THIS
WAY. HOWEVER...THE MAIN BAND OF SHOWERS AND THUNDERSTORMS (NOW
COMING INTO WESTERN PORTIONS OF THE FORECAST AREA) IS BEING
TRIGGERED BY A WEAK SURFACE TROUGH RUNNING OUT A DECENT WAYS IN
ADVANCE OF THE FRONT. REGIONAL RADARS REVEAL A FEW ROBUST CELLS WITH
A FAIR AMOUNT OF LIGHTNING AND HEAVY DOWNPOURS APPROACHING THE MS
RIVER...AND ONLY ISOLATED CELLS BETWEEN THE MS RIVER AND I-55.
FORTUNATELY...ATMOSPHERIC INSTABILITY IS NOT HIGH AND WIND SHEAR IS
REALLY INSUFFICIENT TO ORGANIZE STORMS INTO MODES THAT WOULD BE MORE
WORRISOME FOR SEVERE WEATHER.
EXPECTING ALL THIS ACTIVITY TO CONTINUE TO TREND EAST THROUGH THIS
EVENING...WORKING INTO THE I-55 CORRIDOR BY EARLY THIS EVENING.
LATEST HIRES HRRR RUNS STILL SUGGEST A WEST TO EAST GRADIENT OF FUEL
(MOISTURE ADVECTION AND INSTABILITY) CATALYZING STORMS WILL DROP OFF
QUICKLY EAST OF I-55...SO EXPECT LATER THIS EVENING THAT CONVECTION
WILL HAVE A VERY DIFFICULT TIME GETTING MUCH INTO EASTERN MS.
HOWEVER...I AM SLIGHTLY WORRIED THAT THE EXPECTED STALLING NORTH TO
SOUTH AXIS OF CONVECTION NEAR THE I-55 CORRIDOR LATER THIS EVENING
COULD BE THE FOCUS FOR MORE REDEVELOPMENT LATER TONIGHT AS GULF
MOISTURE ADVECTION INCREASES SOMEWHAT (IN TANDEM WITH INVIGORATING
LOW LEVEL JET). SUCH A SCENARIO COULD POTENTIALLY BRING HEAVY RAIN
WORRIES LATER TONIGHT INTO EARLY TOMORROW INTO PLAY A LITTLE FURTHER
EAST THAN WE WERE PREVIOUSLY ANTICIPATING...BUT FOR NOW WE WILL
CONTINUE TO KEEP THE MAIN LIMITED RISK OF HEAVY RAIN ISSUES LATE
TONIGHT INTO TOMORROW CONFINED TO WESTERN ZONES. THIS LATTER AREA
SHOULD THEORETICALLY EXPERIENCE THE BEST LIFT AND MOISTURE ADVECTION
THROUGH THIS TIME IF MESOSCALE INFLUENCES FROM INCOMING WEAK MCS
DOES NOT OVERLY BIAS THE SYNOPTIC SETUP.
ONCE AGAIN...THE RISK OF SEVERE STORMS THROUGH TONIGHT AND EARLY
TOMORROW LOOKS TOO LOW TO MENTION IN THE HWO OR GRAPHICS...BUT THERE
MAY BE A WINDOW TOMORROW AFTERNOON FOR IMPRESSIVE CAPE (MLCAPE NEAR
2000 J/KG) TO BUILD AS THE FRONT ITSELF PUSHES CLOSER TO THE REGION.
AGAIN...SHEAR SHOULD REMAIN VERY MARGINAL FOR MUCH ORGANIZATION TO
STORMS...BUT THE EVEN MARGINAL INSTABILITY MAY PUSH AN ISOLATED
STORM OR TWO TO SEVERE LIMITS IF CAPE VALUES REALLY MANAGE TO PEAK
UP TO (OR ABOVE) THE PREVIOUSLY MENTIONED LEVEL. STILL DO NOT HAVE
QUITE ENOUGH CONFIDENCE TO ISSUE AN OFFICIAL LIMITED RISK FOR SEVERE
STORMS IN THE HWO/GRAPHICS...BECAUSE IT IS MORE LIKELY MOST STORMS
WILL NOT DO MORE THAN PRODUCE BRIEF GUSTY WINDS...SMALL
HAIL...FREQUENT LIGHTNING...AND HEAVY DOWNPOURS. OF COURSE WE WILL
MONITOR CLOSELY FOR ANY NEEDED ADJUSTMENTS TO THIS THINKING.
THE MEAT OF THE UPPER DISTURBANCE DRIVING MOVEMENT OF THE INCOMING
FRONT WILL START TRANSITIONING TO OUR EAST THURSDAY NIGHT...BUT THE
FRONT REALLY LOOKS TO DRAGS ITSELF INTO THE REGION VERY SLOWLY AS
THE IMPETUS FOR MOVEMENT ALOFT IS REALLY FOCUSED WELL TO OUR NORTH.
IT IS POSSIBLE THE TAIL END OF THIS FRONT COULD CONTINUE TO KICK UP
A FEW SHOWERS OR STORMS THROUGH FRIDAY (ESPECIALLY ACROSS CENTRAL
AND EASTERN MS) DESPITE LIFT ALOFT REALLY WEAKENING QUICKLY.
BUT THE FRONT SHOULD GET OUT OF THE WAY BY THE WEEKEND...LEAVING
DECENT AND WARM CONDITIONS AT THE RIGHT TIME. A WEAK DISTURBANCE
SLIDING INTO THE LOWER MS VALLEY ON MONDAY MAY KICK UP A FEW MORE
SHOWERS...AND MAYBE A STORM...SUNDAY NIGHT INTO MONDAY BUT BY THIS
TIME THE BULK OF ENERGY SHOULD START TO SHIFT NORTH AND NORTHWEST OF
OUR AREA. THIS ENERGY INFLUX INTO THE PLAINS AND MID MS VALLEY NEXT
WEEK COULD SPELL SOME STORMY TIMES FOR THEM AND WE WILL HAVE TO
WATCH ANOTHER ROUND OR TWO OF MODEL RUNS TO FIGURE OUT IF THIS
STORMINESS MIGHT NOT SAG INTO AT LEAST NORTHERN PORTIONS OF THE
FORECAST AREA FOR A FEW DAYS NEXT WORK WEEK. OTHERWISE...EXPECT A
TREND TOWARD TYPICAL LATE SPRING WARMTH. /BB/
&&
.AVIATION...A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS IS
CURRENTLY MOVING ACROSS THE AREA THIS EVENING. ALL SITES REMAIN
VFR...BUT EXPECT TEMPO REDUCTIONS TO MVFR IN HEAVIER RAINSHOWERS AT
GLH/GWO/JAN/HBG THIS EVENING AS THE SHOWERS MOVE THROUGH. THE WINDS
WILL REMAIN OUT OF THE SOUTHEAST-SOUTH AT 5-8KTS THROUGH MUCH OF
THE PERIOD./15/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 62 79 61 78 / 64 74 61 30
MERIDIAN 56 78 61 77 / 20 60 68 45
VICKSBURG 62 80 60 80 / 66 64 51 22
HATTIESBURG 60 79 62 78 / 19 51 60 43
NATCHEZ 63 79 61 80 / 69 62 48 26
GREENVILLE 62 78 60 79 / 58 62 50 16
GREENWOOD 63 79 59 78 / 81 65 61 23
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
BB/7/19
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
938 PM CDT WED APR 20 2016
.UPDATE...
Issued at 933 PM CDT Wed Apr 20 2016
Western edge of rain shield is currently clearing the Mississippi
River. Further to the west...a broken line of showers exists from
just east of KJEF to just east of KUIN. These showers are along a
weak cold front which is by and large going to wash out
overnight. Shower activity expected to dissipate along it within
the next couple of hours. Rest of tonight should see decreasing
precipitation chances and sky cover for most locations. Decreased
low temperatures a couple of degrees west of the Mississippi where
combination of a clear sky...light/variable winds...and lowering
dewpoints should promote good conditions for radiational cooling.
Gosselin
&&
.SHORT TERM... (Through Late Tonight)
Issued at 337 PM CDT Wed Apr 20 2016
Widespread showers are moving through the area this afternoon
ahead of a strong vortmax on the eastern side of the upper level low
over Nebraska. 850mb winds have turned to the southwest ahead of
this system bringing plenty of moisture up from the southeast Plains
and lower Mississippi Valley. There is a wind shift to the west
from about 850mb to the surface forecast to come through the area
tonight, and this wind shift should cut off much of the low level
moisture which will shut off the precip as it passes. This should
happen west of the Mississippi river by 06Z and through our eastern
CWFA by 10-12Z Thursday. There is another shot at more convection
on Thursday as the cold core of the upper low moves across northern
portions of the area. Lapse rates steepen nicely and there will
be another low level trof to provide lift. Not sure right now how
much convection there will be, but it`s certainly worth chance
PoPs...especially over northern portions of the area.
Carney
.LONG TERM... (Thursday through Next Wednesday)
Issued at 337 PM CDT Wed Apr 20 2016
Upper level low will open up and finally shift east of the region
Thursday night with the associated surface low dragging a cold front
southeastward through our forecast area. There may be lingering
showers, mainly east of the Mississippi River Thursday evening, but
the precipitation should shift completely east of the forecast area
by late Thursday night. The NAM model has some light QPF for
southwest IL on Friday, but it looks a little too far west with the
upper level trough compared to the GFS and ECMWF models. For now
will keep the forecast dry for Friday, although there should be some
low level cloud cover at least over the eastern portion of the
forecast area. Cooler temperatures can be expected Friday night due
to a clearing sky with surface ridging extending from the Great
Lakes region southwest into MO. A warming trend will begin on
Saturday due to upper level ridging over the region, and as
surface/low level winds become southeasterly/southerly as the
surface/850 mb ridge shifts east-southeast of the region.
Temperatures by Sunday should be about 10-15 degrees above normal
for late April. Precipitation will return to our area Sunday night
as an upper level low or trough moves eastward through the northern
Plains while an associated surface low drags a cold front
southeastward into our area. The GFS is stronger or deeper with the
upper level low and surface low compared to the ECMWF model and is
more progressive with the front. For now will keep chance pops going
for Monday through Tuesday, although if the GFS model solution turns
out to be correct there should be a break in the precipitation
during this period as surface ridging builds southward into the area
behind the cold front. The ECMWF model has convection continuing
across parts of the area during this period as the cold front sags
only slowly southward through our forecast area. Precipitation
should ramp up across the area Tuesday night into Wednesday as
another upper level low moves into the Plains and a warm front
approaches.
GKS
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 637 PM CDT Wed Apr 20 2016
Light rain should continue to affect the metro terminals into the
mid evening hours before pushing off slowly to the east. Frontal
boundary will shortly move through KCOU and KUIN brining an end to
the shower threat as well as shifting winds from the south to the
west. Scattered showers/storms expected to develop by early
afternoon on Thursday.
Specifics for KSTL:
Expect light rain to end by late evening. Expect dry weather then
until possibly early Thursday afternoon with scattered
showers/storms develop across the area. Winds will also increase a
bit out of the southwest on Thursday afternoon with some gusts of
20-25 knots as well.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Springfield MO
701 PM CDT WED APR 20 2016
.SHORT TERM...(This evening through Thursday morning)
Issued at 220 PM CDT Wed Apr 20 2016
Scattered showers and a few rumbles of thunder have been observed
today across the eastern Ozarks, ahead of a weak frontal boundary
that is passing through the area. That front will sweep east
through the rest of this evening, with some clearing and advection
of dry air in its wake. Will need to watch fog potential across
southern/south central Missouri tonight, where rain fell and
skies may clear just long enough for patchy ground fog to form.
Any clearing will be fairly short lived however, as another lobe
of vorticity rounds the base of the upper low toward sunrise. This
will likely result in renewed cloud cover and set the stage for
additional shower chances Thursday morning.
.LONG TERM...(Thursday through Wednesday)
Issued at 220 PM CDT Wed Apr 20 2016
Showers and a few isolated rumbles of thunder will again be
possible across portions of the Ozarks during the day Thursday as
the slow moving upper level low finally swings northeast of the
region taking the clouds and rain with it.
Upper level ridging will replace the departing system and bring
very pleasant conditions to the region for Friday and into early
Sunday afternoon with afternoon highs climbing into the 70s.
A strong and quick moving storm system will begin to move into
the region late Sunday afternoon into the evening hours bringing
return chances for showers and thunderstorms through early Monday
morning. A quick moving shortwave ridge will move over the region
for Tuesday followed quickly by another storm system that will
bring more rain and storm chances to the area late Tuesday night
through Wednesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 642 PM CDT Wed Apr 20 2016
For the KSGF/KJLN/KBBG tafs: Low pressure will move slowly east
from IA to IL with a sfc trough passing through the region late
in the taf period. High res model guidance shows some spotty
light showers with VFR ceilings moving into the area toward
12z/7am and have included vcsh for all tafs. Most guidance is
indicating fog east and southeast of KSGF late tonight and
included IFR cat fog in the KBBG taf 10z-14z.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Boxell
LONG TERM...Hatch
AVIATION...DSA
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
641 PM CDT WED APR 20 2016
.SHORT TERM... (Through Late Tonight)
Issued at 337 PM CDT Wed Apr 20 2016
Widespread showers are moving through the area this afternoon
ahead of a strong vortmax on the eastern side of the upper level low
over Nebraska. 850mb winds have turned to the southwest ahead of
this system bringing plenty of moisture up from the southeast Plains
and lower Mississippi Valley. There is a wind shift to the west
from about 850mb to the surface forecast to come through the area
tonight, and this wind shift should cut off much of the low level
moisture which will shut off the precip as it passes. This should
happen west of the Mississippi river by 06Z and through our eastern
CWFA by 10-12Z Thursday. There is another shot at more convection
on Thursday as the cold core of the upper low moves across northern
portions of the area. Lapse rates steepen nicely and there will
be another low level trof to provide lift. Not sure right now how
much convection there will be, but it`s certainly worth chance
PoPs...especially over northern portions of the area.
Carney
.LONG TERM... (Thursday through Next Wednesday)
Issued at 337 PM CDT Wed Apr 20 2016
Upper level low will open up and finally shift east of the region
Thursday night with the associated surface low dragging a cold front
southeastward through our forecast area. There may be lingering
showers, mainly east of the Mississippi River Thursday evening, but
the precipitation should shift completely east of the forecast area
by late Thursday night. The NAM model has some light QPF for
southwest IL on Friday, but it looks a little too far west with the
upper level trough compared to the GFS and ECMWF models. For now
will keep the forecast dry for Friday, although there should be some
low level cloud cover at least over the eastern portion of the
forecast area. Cooler temperatures can be expected Friday night due
to a clearing sky with surface ridging extending from the Great
Lakes region southwest into MO. A warming trend will begin on
Saturday due to upper level ridging over the region, and as
surface/low level winds become southeasterly/southerly as the
surface/850 mb ridge shifts east-southeast of the region.
Temperatures by Sunday should be about 10-15 degrees above normal
for late April. Precipitation will return to our area Sunday night
as an upper level low or trough moves eastward through the northern
Plains while an associated surface low drags a cold front
southeastward into our area. The GFS is stronger or deeper with the
upper level low and surface low compared to the ECMWF model and is
more progressive with the front. For now will keep chance pops going
for Monday through Tuesday, although if the GFS model solution turns
out to be correct there should be a break in the precipitation
during this period as surface ridging builds southward into the area
behind the cold front. The ECMWF model has convection continuing
across parts of the area during this period as the cold front sags
only slowly southward through our forecast area. Precipitation
should ramp up across the area Tuesday night into Wednesday as
another upper level low moves into the Plains and a warm front
approaches.
GKS
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 637 PM CDT Wed Apr 20 2016
Light rain should continue to affect the metro terminals into the
mid evening hours before pushing off slowly to the east. Frontal
boundary will shortly move through KCOU and KUIN brining an end to
the shower threat as well as shifting winds from the south to the
west. Scattered showers/storms expected to develop by early
afternoon on Thursday.
Specifics for KSTL:
Expect light rain to end by late evening. Expect dry weather then
until possibly early Thursday afternoon with scattered
showers/storms develop across the area. Winds will also increase a
bit out of the southwest on Thursday afternoon with some gusts of
20-25 knots as well.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
641 PM CDT WED APR 20 2016
.SHORT TERM... (Through Late Tonight)
Issued at 337 PM CDT Wed Apr 20 2016
Widespread showers are moving through the area this afternoon
ahead of a strong vortmax on the eastern side of the upper level low
over Nebraska. 850mb winds have turned to the southwest ahead of
this system bringing plenty of moisture up from the southeast Plains
and lower Mississippi Valley. There is a wind shift to the west
from about 850mb to the surface forecast to come through the area
tonight, and this wind shift should cut off much of the low level
moisture which will shut off the precip as it passes. This should
happen west of the Mississippi river by 06Z and through our eastern
CWFA by 10-12Z Thursday. There is another shot at more convection
on Thursday as the cold core of the upper low moves across northern
portions of the area. Lapse rates steepen nicely and there will
be another low level trof to provide lift. Not sure right now how
much convection there will be, but it`s certainly worth chance
PoPs...especially over northern portions of the area.
Carney
.LONG TERM... (Thursday through Next Wednesday)
Issued at 337 PM CDT Wed Apr 20 2016
Upper level low will open up and finally shift east of the region
Thursday night with the associated surface low dragging a cold front
southeastward through our forecast area. There may be lingering
showers, mainly east of the Mississippi River Thursday evening, but
the precipitation should shift completely east of the forecast area
by late Thursday night. The NAM model has some light QPF for
southwest IL on Friday, but it looks a little too far west with the
upper level trough compared to the GFS and ECMWF models. For now
will keep the forecast dry for Friday, although there should be some
low level cloud cover at least over the eastern portion of the
forecast area. Cooler temperatures can be expected Friday night due
to a clearing sky with surface ridging extending from the Great
Lakes region southwest into MO. A warming trend will begin on
Saturday due to upper level ridging over the region, and as
surface/low level winds become southeasterly/southerly as the
surface/850 mb ridge shifts east-southeast of the region.
Temperatures by Sunday should be about 10-15 degrees above normal
for late April. Precipitation will return to our area Sunday night
as an upper level low or trough moves eastward through the northern
Plains while an associated surface low drags a cold front
southeastward into our area. The GFS is stronger or deeper with the
upper level low and surface low compared to the ECMWF model and is
more progressive with the front. For now will keep chance pops going
for Monday through Tuesday, although if the GFS model solution turns
out to be correct there should be a break in the precipitation
during this period as surface ridging builds southward into the area
behind the cold front. The ECMWF model has convection continuing
across parts of the area during this period as the cold front sags
only slowly southward through our forecast area. Precipitation
should ramp up across the area Tuesday night into Wednesday as
another upper level low moves into the Plains and a warm front
approaches.
GKS
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 637 PM CDT Wed Apr 20 2016
Light rain should continue to affect the metro terminals into the
mid evening hours before pushing off slowly to the east. Frontal
boundary will shortly move through KCOU and KUIN brining an end to
the shower threat as well as shifting winds from the south to the
west. Scattered showers/storms expected to develop by early
afternoon on Thursday.
Specifics for KSTL:
Expect light rain to end by late evening. Expect dry weather then
until possibly early Thursday afternoon with scattered
showers/storms develop across the area. Winds will also increase a
bit out of the southwest on Thursday afternoon with some gusts of
20-25 knots as well.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
631 PM CDT WED APR 20 2016
.Discussion...
Issued at 313 PM CDT WED APR 20 2016
For most of the forecast area, the rain this morning cleared out
early this afternoon. Within the last hour or so, reflectivity has
lit back up along a boundary currently laid out vertically across
eastern MO. However, this very broken, thin line of precip is already
on the very eastern edge of the forecast area with nothing else
currently popping up on radar. As for the cloud cover, other than
some occasional breaks, they`re here to stay through tomorrow night.
Surface low currently in western IA responsible for the cloud cover
and precip will be relatively slow to exit out of the area. Parent
upper low will finally phase with the larger scale pattern by the end
of the week, allowing for a progressiveness of the weather, but not
before periodic rain chances persist through tomorrow. Upper-level
ridging will then briefly take control into the weekend, allowing for
dry conditions and warming temps. Precip chances will once again
enter back into the forecast area Sunday as a low pressure system
crosses the Upper Plains. What will need to be monitored is the
timing of the associated frontal boundary late Sunday as there may be
enough instability and shear to work with to allow the opportunity
for storms to become feisty. Stay tuned as the models hone in better
on this system, then focus will shift to the next low right on its
heels by the middle of next week. Looks to be another unsettled week
ahead.
Temperatures wise, as already alluded to, highs will warm back into
the 70s by this weekend, flirting with perhaps some 80s on Sunday.
Temps will then moderate by the start of the next work week with near
or slightly above normal temps anticipated through the forecast
period.
&&
.Aviation...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 631 PM CDT WED APR 20 2016
VFR conditions spread across the terminals late this afternoon as
today`s low clouds scattered out. More low clouds will sweep across
the region around sunrise Thursday morning along with the potential
for some showers, but confidence in any activity directly affecting
any of the terminals is rather low. Have also kept clouds in the MVFR
range, but this might need adjustment overnight as CIGs develop and
move in. Otherwise, expect surface winds to stay from the west
through the night and start to veer to the north through the day
Thursday.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...lg
Aviation...Cutter
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
631 PM CDT WED APR 20 2016
.Discussion...
Issued at 313 PM CDT WED APR 20 2016
For most of the forecast area, the rain this morning cleared out
early this afternoon. Within the last hour or so, reflectivity has
lit back up along a boundary currently laid out vertically across
eastern MO. However, this very broken, thin line of precip is already
on the very eastern edge of the forecast area with nothing else
currently popping up on radar. As for the cloud cover, other than
some occasional breaks, they`re here to stay through tomorrow night.
Surface low currently in western IA responsible for the cloud cover
and precip will be relatively slow to exit out of the area. Parent
upper low will finally phase with the larger scale pattern by the end
of the week, allowing for a progressiveness of the weather, but not
before periodic rain chances persist through tomorrow. Upper-level
ridging will then briefly take control into the weekend, allowing for
dry conditions and warming temps. Precip chances will once again
enter back into the forecast area Sunday as a low pressure system
crosses the Upper Plains. What will need to be monitored is the
timing of the associated frontal boundary late Sunday as there may be
enough instability and shear to work with to allow the opportunity
for storms to become feisty. Stay tuned as the models hone in better
on this system, then focus will shift to the next low right on its
heels by the middle of next week. Looks to be another unsettled week
ahead.
Temperatures wise, as already alluded to, highs will warm back into
the 70s by this weekend, flirting with perhaps some 80s on Sunday.
Temps will then moderate by the start of the next work week with near
or slightly above normal temps anticipated through the forecast
period.
&&
.Aviation...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 631 PM CDT WED APR 20 2016
VFR conditions spread across the terminals late this afternoon as
today`s low clouds scattered out. More low clouds will sweep across
the region around sunrise Thursday morning along with the potential
for some showers, but confidence in any activity directly affecting
any of the terminals is rather low. Have also kept clouds in the MVFR
range, but this might need adjustment overnight as CIGs develop and
move in. Otherwise, expect surface winds to stay from the west
through the night and start to veer to the north through the day
Thursday.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...lg
Aviation...Cutter
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
405 PM CDT WED APR 20 2016
.Discussion...
Issued at 313 PM CDT WED APR 20 2016
For most of the forecast area, the rain this morning cleared out
early this afternoon. Within the last hour or so, reflectivity has
lit back up along a boundary currently laid out vertically across
eastern MO. However, this very broken, thin line of precip is already
on the very eastern edge of the forecast area with nothing else
currently popping up on radar. As for the cloud cover, other than
some occasional breaks, they`re here to stay through tomorrow night.
Surface low currently in western IA responsible for the cloud cover
and precip will be relatively slow to exit out of the area. Parent
upper low will finally phase with the larger scale pattern by the end
of the week, allowing for a progressiveness of the weather, but not
before periodic rain chances persist through tomorrow. Upper-level
ridging will then briefly take control into the weekend, allowing for
dry conditions and warming temps. Precip chances will once again
enter back into the forecast area Sunday as a low pressure system
crosses the Upper Plains. What will need to be monitored is the
timing of the associated frontal boundary late Sunday as there may be
enough instability and shear to work with to allow the opportunity
for storms to become feisty. Stay tuned as the models hone in better
on this system, then focus will shift to the next low right on its
heels by the middle of next week. Looks to be another unsettled week
ahead.
Temperatures wise, as already alluded to, highs will warm back into
the 70s by this weekend, flirting with perhaps some 80s on Sunday.
Temps will then moderate by the start of the next work week with near
or slightly above normal temps anticipated through the forecast
period.
&&
.Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1242 PM CDT WED APR 20 2016
MVFR ceilings have been hanging on into the early afternoon hours but
is anticipated to finally rise by mid-afternoon. For most of the
overnight hours at the four terminals, ceilings should be in the VFR
category before dropping back down in the pre-dawn hours on Thursday.
For this TAF issuance, have indicated MVFR ceilings but is not out of
the realm of possibilities to dip down into the IFR category tomorrow
morning, which may need to be included in subsequent forecasts. Look
for the winds to remain primarily out of the W-SW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...lg
Aviation...lg
Area Forecast Discussion
National Weather Service Saint Louis MO
338 PM CDT WED APR 20 2016
.SHORT TERM... (Through Late Tonight)
Issued at 337 PM CDT Wed Apr 20 2016
Widespread showers are moving through the area this afternoon
ahead of a strong vortmax on the eastern side of the upper level low
over Nebraska. 850mb winds have turned to the southwest ahead of
this system bringing plenty of moisture up from the southeast Plains
and lower Mississippi Valley. There is a wind shift to the west
from about 850mb to the surface forecast to come through the area
tonight, and this wind shift should cut off much of the low level
moisture which will shut off the precip as it passes. This should
happen west of the Mississippi river by 06Z and through our eastern
CWFA by 10-12Z Thursday. There is another shot at more convection
on Thursday as the cold core of the upper low moves across northern
portions of the area. Lapse rates steepen nicely and there will
be another low level trof to provide lift. Not sure right now how
much convection there will be, but it`s certainly worth chance
PoPs...especially over northern portions of the area.
Carney
.LONG TERM... (Thursday through Next Wednesday)
Issued at 337 PM CDT Wed Apr 20 2016
Upper level low will open up and finally shift east of the region
Thursday night with the associated surface low dragging a cold front
southeastward through our forecast area. There may be lingering
showers, mainly east of the Mississippi River Thursday evening, but
the precipitation should shift completely east of the forecast area
by late Thursday night. The NAM model has some light QPF for
southwest IL on Friday, but it looks a little too far west with the
upper level trough compared to the GFS and ECMWF models. For now
will keep the forecast dry for Friday, although there should be some
low level cloud cover at least over the eastern portion of the
forecast area. Cooler temperatures can be expected Friday night due
to a clearing sky with surface ridging extending from the Great
Lakes region southwest into MO. A warming trend will begin on
Saturday due to upper level ridging over the region, and as
surface/low level winds become southeasterly/southerly as the
surface/850 mb ridge shifts east-southeast of the region.
Temperatures by Sunday should be about 10-15 degrees above normal
for late April. Precipitation will return to our area Sunday night
as an upper level low or trough moves eastward through the northern
Plains while an associated surface low drags a cold front
southeastward into our area. The GFS is stronger or deeper with the
upper level low and surface low compared to the ECMWF model and is
more progressive with the front. For now will keep chance pops going
for Monday through Tuesday, although if the GFS model solution turns
out to be correct there should be a break in the precipitation
during this period as surface ridging builds southward into the area
behind the cold front. The ECMWF model has convection continuing
across parts of the area during this period as the cold front sags
only slowly southward through our forecast area. Precipitation
should ramp up across the area Tuesday night into Wednesday as
another upper level low moves into the Plains and a warm front
approaches.
GKS
&&
.AVIATION... (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1247 PM CDT Wed Apr 20 2016
Areas of showers and isolated thunderstorms with associated MVFR
and potentially IFR flight conditions will move northeast across
the area this afternoon. Showers should diminish and move east of
the region this evening leaving an isolated shower or two possible
overnight. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Specifics for KSTL:
Area of showers will impact the terminal early this afternoon
bringing MVFR CIGS/VSBYS. Expect conditions to improve after the
rain ends later this afternoon...though timing of the improvement
is uncertain. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Saint Louis MO
338 PM CDT WED APR 20 2016
.SHORT TERM... (Through Late Tonight)
Issued at 337 PM CDT Wed Apr 20 2016
Widespread showers are moving through the area this afternoon
ahead of a strong vortmax on the eastern side of the upper level low
over Nebraska. 850mb winds have turned to the southwest ahead of
this system bringing plenty of moisture up from the southeast Plains
and lower Mississippi Valley. There is a wind shift to the west
from about 850mb to the surface forecast to come through the area
tonight, and this wind shift should cut off much of the low level
moisture which will shut off the precip as it passes. This should
happen west of the Mississippi river by 06Z and through our eastern
CWFA by 10-12Z Thursday. There is another shot at more convection
on Thursday as the cold core of the upper low moves across northern
portions of the area. Lapse rates steepen nicely and there will
be another low level trof to provide lift. Not sure right now how
much convection there will be, but it`s certainly worth chance
PoPs...especially over northern portions of the area.
Carney
.LONG TERM... (Thursday through Next Wednesday)
Issued at 337 PM CDT Wed Apr 20 2016
Upper level low will open up and finally shift east of the region
Thursday night with the associated surface low dragging a cold front
southeastward through our forecast area. There may be lingering
showers, mainly east of the Mississippi River Thursday evening, but
the precipitation should shift completely east of the forecast area
by late Thursday night. The NAM model has some light QPF for
southwest IL on Friday, but it looks a little too far west with the
upper level trough compared to the GFS and ECMWF models. For now
will keep the forecast dry for Friday, although there should be some
low level cloud cover at least over the eastern portion of the
forecast area. Cooler temperatures can be expected Friday night due
to a clearing sky with surface ridging extending from the Great
Lakes region southwest into MO. A warming trend will begin on
Saturday due to upper level ridging over the region, and as
surface/low level winds become southeasterly/southerly as the
surface/850 mb ridge shifts east-southeast of the region.
Temperatures by Sunday should be about 10-15 degrees above normal
for late April. Precipitation will return to our area Sunday night
as an upper level low or trough moves eastward through the northern
Plains while an associated surface low drags a cold front
southeastward into our area. The GFS is stronger or deeper with the
upper level low and surface low compared to the ECMWF model and is
more progressive with the front. For now will keep chance pops going
for Monday through Tuesday, although if the GFS model solution turns
out to be correct there should be a break in the precipitation
during this period as surface ridging builds southward into the area
behind the cold front. The ECMWF model has convection continuing
across parts of the area during this period as the cold front sags
only slowly southward through our forecast area. Precipitation
should ramp up across the area Tuesday night into Wednesday as
another upper level low moves into the Plains and a warm front
approaches.
GKS
&&
.AVIATION... (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1247 PM CDT Wed Apr 20 2016
Areas of showers and isolated thunderstorms with associated MVFR
and potentially IFR flight conditions will move northeast across
the area this afternoon. Showers should diminish and move east of
the region this evening leaving an isolated shower or two possible
overnight. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Specifics for KSTL:
Area of showers will impact the terminal early this afternoon
bringing MVFR CIGS/VSBYS. Expect conditions to improve after the
rain ends later this afternoon...though timing of the improvement
is uncertain. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
221 PM CDT WED APR 20 2016
.SHORT TERM...(This evening through Thursday morning)
Issued at 220 PM CDT Wed Apr 20 2016
Scattered showers and a few rumbles of thunder have been observed
today across the eastern Ozarks, ahead of a weak frontal boundary
that is passing through the area. That front will sweep east
through the rest of this evening, with some clearing and advection
of dry air in its wake. Will need to watch fog potential across
southern/south central Missouri tonight, where rain fell and
skies may clear just long enough for patchy ground fog to form.
Any clearing will be fairly short lived however, as another lobe
of vorticity rounds the base of the upper low toward sunrise. This
will likely result in renewed cloud cover and set the stage for
additional shower chances Thursday morning.
.LONG TERM...(Thursday through Wednesday)
Issued at 220 PM CDT Wed Apr 20 2016
Showers and a few isolated rumbles of thunder will again be
possible across portions of the Ozarks during the day Thursday as
the slow moving upper level low finally swings northeast of the
region taking the clouds and rain with it.
Upper level ridging will replace the departing system and bring
very pleasant conditions to the region for Friday and into early
Sunday afternoon with afternoon highs climbing into the 70s.
A strong and quick moving storm system will begin to move into
the region late Sunday afternoon into the evening hours bringing
return chances for showers and thunderstorms through early Monday
morning. A quick moving shortwave ridge will move over the region
for Tuesday followed quickly by another storm system that will
bring more rain and storm chances to the area late Tuesday night
through Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1213 PM CDT Wed Apr 20 2016
MVFR to IFR cigs early this afternoon should improve heading into
the latter portion of this afternoon and this evening. Rain
chances will remain widely scattered, with little significant
impact expected where it does occur. Winds will be westerly.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Boxell
LONG TERM...Hatch
AVIATION...Boxell
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
123 PM CDT WED APR 20 2016
.SHORT TERM... (Today and Tonight)
Issued at 324 AM CDT Wed Apr 20 2016
A large swath of showers and some thunderstorms extended from
eastern KS into eastern OK around midnight. This activity was in
part due to a well-defined short wave trof rotating through the
central Plains. Since that time the swath has fragmented and
weakened considerably with the main concentration of precipitation
across northeast KS and southeast NE. Further south the coverage
of precipitation in advance of the short wave trof consisted of
small bands and scattered showers. I think this is what we will
mainly see this morning as the short wave continues to rotate to
the northeast across the area. In the wake of this morning
activity, additional showers and thunderstorms, possibly a broken
line, are expected to develop around mid afternoon across eastern
MO along/ahead of the advancing cold front pushing then push
across SW/SC IL in the evening.
Glass
.LONG TERM... (Tonight through Tuesday)
Issued at 314 AM CDT Wed Apr 20 2016
The upper low/trof currently centered in western NE will evolve
into a mobile positively tilted trof by Thursday. A cold pocket
aloft will contribute to weak instability, peaking with diurnal
heating, and will support scattered primarily afternoon and early
evening showers and thunderstorms along a secondary cold front.
The threat of precipitation will wane with the loss of heating and
passage of the upper trof axis Thursday evening, and yet another
cold front from the north will move through the area from late
Thursday night though Friday morning. High pressure will then
build into the region on Friday in the wake of this later front
and dominate through early Saturday. Retreating high pressure on
Saturday will allow return flow and WAA to get underway on
Saturday afternoon. By Sunday, temperatures will back around the
80 degree mark as ridging aloft builds into the area and south-
southwesterly low level flow/WAA is well established. Beyond
Sunday there is a good deal of diversity in the model solutions
leading to low confidence in details. It does however appear that
next week will feature at least one period of stormy conditions
more typical of spring.
Glass
&&
.AVIATION... (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1247 PM CDT Wed Apr 20 2016
Areas of showers and isolated thunderstorms with associated MVFR
and potentially IFR flight conditions will move northeast across
the area this afternoon. Showers should diminish and move east of
the region this evening leaving an isolated shower or two possible
overnight. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Specifics for KSTL:
Area of showers will impact the terminal early this afternoon
bringing MVFR CIGS/VSBYS. Expect conditions to improve after the
rain ends later this afternoon...though timing of the improvement
is uncertain. CIG/VIS trends are low confidence tonight as some
partial clearing is possible. If this occurs, there will likely be
fog...tho again this is low confidence.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1247 PM CDT WED APR 20 2016
.Discussion...
Issued at 301 AM CDT WED APR 20 2016
A large area of rain tracking across northeast KS this morning is in
response to a sharply-negatively tilted shortwave trough tracking
through the area, and associated cyclogenesis occurring over
northeast Kansas. Both of these features will track into southern
Iowa by mid- to late-morning, taking the bulk of precipitation with
them. However, a few lingering showers and isolated storms are
possible through the afternoon, mainly across northern and central MO
where a weak front will be tracking through. Shear along the front
will be a bit higher today, so shouldn`t be supportive of the weak
landspouts that we`ve seen across parts of Missouri the past couple
of days.
Large upper low will begin shifting east of the area as an open wave
late tonight into Thursday as it phases with the northern jet stream.
Scattered showers are possible late tonight and into Thursday as this
system passes through with the highest chances across northern
Missouri. Low-level ridging building in behind this system will
finally bring an end to precipitation chances altogether Thursday
evening.
Broad upper-level ridging will build into much of the central U.S.
Friday and Saturday, keeping dry weather through most of the weekend
while temperatures gradually climb to near 80 degrees by Sunday. This
ridge will flatten by Sunday afternoon, setting the stage for more
active weather heading into next week as another deep upper trough
takes shape to the west. This trough will likely send several rounds
of precipitation into the region next week, some of which may need to
be watched for the potential for strong/severe storms.
&&
.Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1242 PM CDT WED APR 20 2016
MVFR ceilings have been hanging on into the early afternoon hours but
is anticipated to finally rise by mid-afternoon. For most of the
overnight hours at the four terminals, ceilings should be in the VFR
category before dropping back down in the pre-dawn hours on Thursday.
For this TAF issuance, have indicated MVFR ceilings but is not out of
the realm of possibilities to dip down into the IFR category tomorrow
morning, which may need to be included in subsequent forecasts. Look
for the winds to remain primarily out of the W-SW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...lg
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1247 PM CDT WED APR 20 2016
.Discussion...
Issued at 301 AM CDT WED APR 20 2016
A large area of rain tracking across northeast KS this morning is in
response to a sharply-negatively tilted shortwave trough tracking
through the area, and associated cyclogenesis occurring over
northeast Kansas. Both of these features will track into southern
Iowa by mid- to late-morning, taking the bulk of precipitation with
them. However, a few lingering showers and isolated storms are
possible through the afternoon, mainly across northern and central MO
where a weak front will be tracking through. Shear along the front
will be a bit higher today, so shouldn`t be supportive of the weak
landspouts that we`ve seen across parts of Missouri the past couple
of days.
Large upper low will begin shifting east of the area as an open wave
late tonight into Thursday as it phases with the northern jet stream.
Scattered showers are possible late tonight and into Thursday as this
system passes through with the highest chances across northern
Missouri. Low-level ridging building in behind this system will
finally bring an end to precipitation chances altogether Thursday
evening.
Broad upper-level ridging will build into much of the central U.S.
Friday and Saturday, keeping dry weather through most of the weekend
while temperatures gradually climb to near 80 degrees by Sunday. This
ridge will flatten by Sunday afternoon, setting the stage for more
active weather heading into next week as another deep upper trough
takes shape to the west. This trough will likely send several rounds
of precipitation into the region next week, some of which may need to
be watched for the potential for strong/severe storms.
&&
.Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1242 PM CDT WED APR 20 2016
MVFR ceilings have been hanging on into the early afternoon hours but
is anticipated to finally rise by mid-afternoon. For most of the
overnight hours at the four terminals, ceilings should be in the VFR
category before dropping back down in the pre-dawn hours on Thursday.
For this TAF issuance, have indicated MVFR ceilings but is not out of
the realm of possibilities to dip down into the IFR category tomorrow
morning, which may need to be included in subsequent forecasts. Look
for the winds to remain primarily out of the W-SW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...lg
Area Forecast Discussion
National Weather Service Springfield MO
1217 PM CDT WED APR 20 2016
...Aviation Update...
.SHORT TERM...(Today through Thursday)
Issued at 250 AM CDT Wed Apr 20 2016
The upper level low that has been anchored out west the past few
days will begin an eastward track the next couple of days as it
opens up. A lead shortwave will lift north of the area today while
a weak front pushes east across the area. Isolated to scattered
showers will continue across the area today. However with the
primary lifting mechanism tracking north of the area the
potential for a widespread soaking rain is diminishing. The lack
of instability will result in limited development of
thunderstorms.
The potential for a few showers will continue tonight and Thursday
as the primary upper level trough axis makes its way across the
region.
Overall confidence in the short term forecast is high.
.LONG TERM...(Thursday through Tuesday)
Issued at 250 AM CDT Wed Apr 20 2016
A warming trend along with more sunshine will return Friday into
the weekend in the wake of the exiting upper level trough. Upper
level ridging and southerly winds will help to push high
temperatures well into the 70s to near 80 degrees.
A more active weather pattern will return next week as a series of
disturbances track eastward across the region. However, forecast
certainty of the details in regards to precipitation timing and
coverage remain low.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1213 PM CDT Wed Apr 20 2016
MVFR to IFR cigs early this afternoon should improve heading into
the latter portion of this afternoon and this evening. Rain
chances will remain widely scattered, with little significant
impact expected where it does occur. Winds will be westerly.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Boxell
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
621 AM CDT WED APR 20 2016
.SHORT TERM... (Today and Tonight)
Issued at 324 AM CDT Wed Apr 20 2016
A large swath of showers and some thunderstorms extended from
eastern KS into eastern OK around midnight. This activity was in
part due to a well-defined short wave trof rotating through the
central Plains. Since that time the swath has fragmented and
weakened considerably with the main concentration of precipitation
across northeast KS and southeast NE. Further south the coverage
of precipitation in advance of the short wave trof consisted of
small bands and scattered showers. I think this is what we will
mainly see this morning as the short wave continues to rotate to
the northeast across the area. In the wake of this morning
activity, additional showers and thunderstorms, possibly a broken
line, are expected to develop around mid afternoon across eastern
MO along/ahead of the advancing cold front pushing then push
across SW/SC IL in the evening.
Glass
.LONG TERM... (Tonight through Tuesday)
Issued at 314 AM CDT Wed Apr 20 2016
The upper low/trof currently centered in western NE will evolve
into a mobile positively tilted trof by Thursday. A cold pocket
aloft will contribute to weak instability, peaking with diurnal
heating, and will support scattered primarily afternoon and early
evening showers and thunderstorms along a secondary cold front.
The threat of precipitation will wane with the loss of heating and
passage of the upper trof axis Thursday evening, and yet another
cold front from the north will move through the area from late
Thursday night though Friday morning. High pressure will then
build into the region on Friday in the wake of this later front
and dominate through early Saturday. Retreating high pressure on
Saturday will allow return flow and WAA to get underway on
Saturday afternoon. By Sunday, temperatures will back around the
80 degree mark as ridging aloft builds into the area and south-
southwesterly low level flow/WAA is well established. Beyond
Sunday there is a good deal of diversity in the model solutions
leading to low confidence in details. It does however appear that
next week will feature at least one period of stormy conditions
more typical of spring.
Glass
&&
.AVIATION... (For the 12z TAFs through 12z Thursday Morning)
Issued at 612 AM CDT Wed Apr 20 2016
Area of MVFR ceilings from left over convection to our west last
night will continue to spread east and lift throughout the
morning. Forecasting the cloud base at VFR level by the time it
reaches St. Louis Metro later this afternoon. This may be too
optomistic and will need to be monitored. Otherwise...some
scattered showers and thunderstorms are expected to develop this
afternoon across mainly eastern Missouri and Illinois. Some
potential for fog tonight if sky can clear and wind decreases.
Specifics for KSTL:
Light showers will impact terminal the next few hours with a
better chance of showers and thunderstorms developing this
afternoon. MVFR ceilings to the southwest are expected to lift to
VFR level by the time they advect over the terminal. Could see
some fog develop late tonight if sky can clear and wind decreases.
CVKING
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
620 AM CDT WED APR 20 2016
.Discussion...
Issued at 301 AM CDT WED APR 20 2016
A large area of rain tracking across northeast KS this morning is in
response to a sharply-negatively tilted shortwave trough tracking
through the area, and associated cyclogenesis occurring over
northeast Kansas. Both of these features will track into southern
Iowa by mid- to late-morning, taking the bulk of precipitation with
them. However, a few lingering showers and isolated storms are
possible through the afternoon, mainly across northern and central MO
where a weak front will be tracking through. Shear along the front
will be a bit higher today, so shouldn`t be supportive of the weak
landspouts that we`ve seen across parts of Missouri the past couple
of days.
Large upper low will begin shifting east of the area as an open wave
late tonight into Thursday as it phases with the northern jet stream.
Scattered showers are possible late tonight and into Thursday as this
system passes through with the highest chances across northern
Missouri. Low-level ridging building in behind this system will
finally bring an end to precipitation chances altogether Thursday
evening.
Broad upper-level ridging will build into much of the central U.S.
Friday and Saturday, keeping dry weather through most of the weekend
while temperatures gradually climb to near 80 degrees by Sunday. This
ridge will flatten by Sunday afternoon, setting the stage for more
active weather heading into next week as another deep upper trough
takes shape to the west. This trough will likely send several rounds
of precipitation into the region next week, some of which may need to
be watched for the potential for strong/severe storms.
&&
.Aviation...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 620 AM CDT WED APR 20 2016
Surface low over northeast KS will track into southeast NE over the
next couple of hours, taking most rainfall with it and also bringing
winds around from the southwest. This wind shift will enter far
western MO between 8 AM and 9 AM. A few scattered showers possible
through the morning, otherwise slowly improving conditions with
clouds becoming scattered VFR later this morning and afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...Hawblitzel
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
620 AM CDT WED APR 20 2016
.Discussion...
Issued at 301 AM CDT WED APR 20 2016
A large area of rain tracking across northeast KS this morning is in
response to a sharply-negatively tilted shortwave trough tracking
through the area, and associated cyclogenesis occurring over
northeast Kansas. Both of these features will track into southern
Iowa by mid- to late-morning, taking the bulk of precipitation with
them. However, a few lingering showers and isolated storms are
possible through the afternoon, mainly across northern and central MO
where a weak front will be tracking through. Shear along the front
will be a bit higher today, so shouldn`t be supportive of the weak
landspouts that we`ve seen across parts of Missouri the past couple
of days.
Large upper low will begin shifting east of the area as an open wave
late tonight into Thursday as it phases with the northern jet stream.
Scattered showers are possible late tonight and into Thursday as this
system passes through with the highest chances across northern
Missouri. Low-level ridging building in behind this system will
finally bring an end to precipitation chances altogether Thursday
evening.
Broad upper-level ridging will build into much of the central U.S.
Friday and Saturday, keeping dry weather through most of the weekend
while temperatures gradually climb to near 80 degrees by Sunday. This
ridge will flatten by Sunday afternoon, setting the stage for more
active weather heading into next week as another deep upper trough
takes shape to the west. This trough will likely send several rounds
of precipitation into the region next week, some of which may need to
be watched for the potential for strong/severe storms.
&&
.Aviation...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 620 AM CDT WED APR 20 2016
Surface low over northeast KS will track into southeast NE over the
next couple of hours, taking most rainfall with it and also bringing
winds around from the southwest. This wind shift will enter far
western MO between 8 AM and 9 AM. A few scattered showers possible
through the morning, otherwise slowly improving conditions with
clouds becoming scattered VFR later this morning and afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...Hawblitzel
Area Forecast Discussion
National Weather Service Springfield MO
558 AM CDT WED APR 20 2016
...Update to Aviation Discussion for 12Z TAFS...
.SHORT TERM...(Today through Thursday)
Issued at 250 AM CDT Wed Apr 20 2016
The upper level low that has been anchored out west the past few
days will begin an eastward track the next couple of days as it
opens up. A lead shortwave will lift north of the area today while
a weak front pushes east across the area. Isolated to scattered
showers will continue across the area today. However with the
primary lifting mechanism tracking north of the area the
potential for a widespread soaking rain is diminishing. The lack
of instability will result in limited development of
thunderstorms.
The potential for a few showers will continue tonight and Thursday
as the primary upper level trough axis makes its way across the
region.
Overall confidence in the short term forecast is high.
.LONG TERM...(Thursday through Tuesday)
Issued at 250 AM CDT Wed Apr 20 2016
A warming trend along with more sunshine will return Friday into
the weekend in the wake of the exiting upper level trough. Upper
level ridging and southerly winds will help to push high
temperatures well into the 70s to near 80 degrees.
A more active weather pattern will return next week as a series of
disturbances track eastward across the region. However, forecast
certainty of the details in regards to precipitation timing and
coverage remain low.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 557 AM CDT Wed Apr 20 2016
For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will occur early
this morning and gradually improve this morning with VFR
conditions expected by this afternoon. Fog will also impact the
KBBG TAF site early this morning.
A cold front will spread east across the area later this morning.
A few showers will be possible along the front, but the better
chances for rain will be to the north of the area, so left rain
out of the TAFS. Winds will be out of the southeast ahead of the
front with winds becoming westerly behind the front this
afternoon.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Wise
Area Forecast Discussion
National Weather Service Saint Louis MO
348 AM CDT WED APR 20 2016
.SHORT TERM... (Today and Tonight)
Issued at 324 AM CDT Wed Apr 20 2016
A large swath of showers and some thunderstorms extended from
eastern KS into eastern OK around midnight. This activity was in
part due to a well-defined short wave trof rotating through the
central Plains. Since that time the swath has fragmented and
weakened considerably with the main concentration of precipitation
across northeast KS and southeast NE. Further south the coverage
of precipitation in advance of the short wave trof consisted of
small bands and scattered showers. I think this is what we will
mainly see this morning as the short wave continues to rotate to
the northeast across the area. In the wake of this morning
activity, additional showers and thunderstorms, possibly a broken
line, are expected to develop around mid afternoon across eastern
MO along/ahead of the advancing cold front pushing then push
across SW/SC IL in the evening.
Glass
.LONG TERM... (Tonight through Tuesday)
Issued at 314 AM CDT Wed Apr 20 2016
The upper low/trof currently centered in western NE will evolve
into a mobile positively tilted trof by Thursday. A cold pocket
aloft will contribute to weak instability, peaking with diurnal
heating, and will support scattered primarily afternoon and early
evening showers and thunderstorms along a secondary cold front.
The threat of precipitation will wane with the loss of heating and
passage of the upper trof axis Thursday evening, and yet another
cold front from the north will move through the area from late
Thursday night though Friday morning. High pressure will then
build into the region on Friday in the wake of this later front
and dominate through early Saturday. Retreating high pressure on
Saturday will allow return flow and WAA to get underway on
Saturday afternoon. By Sunday, temperatures will back around the
80 degree mark as ridging aloft builds into the area and south-
southwesterly low level flow/WAA is well established. Beyond
Sunday there is a good deal of diversity in the model solutions
leading to low confidence in details. It does however appear that
next week will feature at least one period of stormy conditions
more typical of spring.
Glass
&&
.AVIATION... (For the 06z TAFs through 06z Wednesday Night)
Issued at 1144 PM CDT Tue Apr 19 2016
Expect rest of tonight to be dry across terminals as rain/storms
have weakened and are dissipating currently across northeastern
Missouri. Some fog possible...particularly at KSUS and KCPS with
at least a partially clearing sky and low T/Td spreads. IFR visbys
not out of the question but for now went MVFR. Thinking there
should be enough clouds at KCOU and KUIN to preclude fog
development but this will have to be watched as well. Still
expecting some scattered showers and possibly a few storms to
affect metro terminals late Wednesay morning. Additional scattered
activity along/ahead of cold front will carry a higher threat of
thunder during the afternoon hours. By Wednesday evening...threat
of showers/storms should push off to the south and east of the
terminals with winds beginning to veer to the southwest as front
slowly moves through the bi-state area.
Specifics for KSTL:
Expecting dry/VFR conditions for rest of tonight. High T/Td spread
expected to prevent fog prevention. Scattered showers/possibly a
storm may affect terminal late morning. Then another break before
another round of showers/storms develops along/ahead of cold front
late afternoon. By Wednesday evening...threat of showers/storms
should push off to the east.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Saint Louis MO
348 AM CDT WED APR 20 2016
.SHORT TERM... (Today and Tonight)
Issued at 324 AM CDT Wed Apr 20 2016
A large swath of showers and some thunderstorms extended from
eastern KS into eastern OK around midnight. This activity was in
part due to a well-defined short wave trof rotating through the
central Plains. Since that time the swath has fragmented and
weakened considerably with the main concentration of precipitation
across northeast KS and southeast NE. Further south the coverage
of precipitation in advance of the short wave trof consisted of
small bands and scattered showers. I think this is what we will
mainly see this morning as the short wave continues to rotate to
the northeast across the area. In the wake of this morning
activity, additional showers and thunderstorms, possibly a broken
line, are expected to develop around mid afternoon across eastern
MO along/ahead of the advancing cold front pushing then push
across SW/SC IL in the evening.
Glass
.LONG TERM... (Tonight through Tuesday)
Issued at 314 AM CDT Wed Apr 20 2016
The upper low/trof currently centered in western NE will evolve
into a mobile positively tilted trof by Thursday. A cold pocket
aloft will contribute to weak instability, peaking with diurnal
heating, and will support scattered primarily afternoon and early
evening showers and thunderstorms along a secondary cold front.
The threat of precipitation will wane with the loss of heating and
passage of the upper trof axis Thursday evening, and yet another
cold front from the north will move through the area from late
Thursday night though Friday morning. High pressure will then
build into the region on Friday in the wake of this later front
and dominate through early Saturday. Retreating high pressure on
Saturday will allow return flow and WAA to get underway on
Saturday afternoon. By Sunday, temperatures will back around the
80 degree mark as ridging aloft builds into the area and south-
southwesterly low level flow/WAA is well established. Beyond
Sunday there is a good deal of diversity in the model solutions
leading to low confidence in details. It does however appear that
next week will feature at least one period of stormy conditions
more typical of spring.
Glass
&&
.AVIATION... (For the 06z TAFs through 06z Wednesday Night)
Issued at 1144 PM CDT Tue Apr 19 2016
Expect rest of tonight to be dry across terminals as rain/storms
have weakened and are dissipating currently across northeastern
Missouri. Some fog possible...particularly at KSUS and KCPS with
at least a partially clearing sky and low T/Td spreads. IFR visbys
not out of the question but for now went MVFR. Thinking there
should be enough clouds at KCOU and KUIN to preclude fog
development but this will have to be watched as well. Still
expecting some scattered showers and possibly a few storms to
affect metro terminals late Wednesay morning. Additional scattered
activity along/ahead of cold front will carry a higher threat of
thunder during the afternoon hours. By Wednesday evening...threat
of showers/storms should push off to the south and east of the
terminals with winds beginning to veer to the southwest as front
slowly moves through the bi-state area.
Specifics for KSTL:
Expecting dry/VFR conditions for rest of tonight. High T/Td spread
expected to prevent fog prevention. Scattered showers/possibly a
storm may affect terminal late morning. Then another break before
another round of showers/storms develops along/ahead of cold front
late afternoon. By Wednesday evening...threat of showers/storms
should push off to the east.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
302 AM CDT WED APR 20 2016
...Chance of Showers Continues into Thursday then a Warmer Weekend...
.SHORT TERM...(Today through Thursday)
Issued at 250 AM CDT Wed Apr 20 2016
The upper level low that has been anchored out west the past few
days will begin an eastward track the next couple of days as it
opens up. A lead shortwave will lift north of the area today while
a weak front pushes east across the area. Isolated to scattered
showers will continue across the area today. However with the
primary lifting mechanism tracking north of the area the
potential for a widespread soaking rain is diminishing. The lack
of instability will result in limited development of
thunderstorms.
The potential for a few showers will continue tonight and Thursday
as the primary upper level trough axis makes its way across the
region.
Overall confidence in the short term forecast is high.
.LONG TERM...(Thursday through Tuesday)
Issued at 250 AM CDT Wed Apr 20 2016
A warming trend along with more sunshine will return Friday into
the weekend in the wake of the exiting upper level trough. Upper
level ridging and southerly winds will help to push high
temperatures well into the 70s to near 80 degrees.
A more active weather pattern will return next week as a series of
disturbances track eastward across the region. However, forecast
certainty of the details in regards to precipitation timing and
coverage remain low.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1147 PM CDT Tue Apr 19 2016
Still playing the IFR/MVFR game tonight with TAFS. Ceilings have
been up and down all evening and should settle in with mostly IFR
during the overnight. Not real hip on rain chances outside of JLN
and have gone with mainly VCSH wording early on. Models show most
of precipitation over northwest MO late tonight as energy lifts
northeast with the slow moving upper low.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
301 AM CDT WED APR 20 2016
.Discussion...
Issued at 301 AM CDT WED APR 20 2016
A large area of rain tracking across northeast KS this morning is in
response to a sharply-negatively tilted shortwave trough tracking
through the area, and associated cyclogenesis occurring over
northeast Kansas. Both of these features will track into southern
Iowa by mid- to late-morning, taking the bulk of precipitation with
them. However, a few lingering showers and isolated storms are
possible through the afternoon, mainly across northern and central MO
where a weak front will be tracking through. Shear along the front
will be a bit higher today, so shouldn`t be supportive of the weak
landspouts that we`ve seen across parts of Missouri the past couple
of days.
Large upper low will begin shifting east of the area as an open wave
late tonight into Thursday as it phases with the northern jet stream.
Scattered showers are possible late tonight and into Thursday as this
system passes through with the highest chances across northern
Missouri. Low-level ridging building in behind this system will
finally bring an end to precipitation chances altogether Thursday
evening.
Broad upper-level ridging will build into much of the central U.S.
Friday and Saturday, keeping dry weather through most of the weekend
while temperatures gradually climb to near 80 degrees by Sunday. This
ridge will flatten by Sunday afternoon, setting the stage for more
active weather heading into next week as another deep upper trough
takes shape to the west. This trough will likely send several rounds
of precipitation into the region next week, some of which may need to
be watched for the potential for strong/severe storms.
&&
.Aviation...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1156 PM CDT TUE APR 19 2016
Rain is currently moving north and will have likely spread across all
the west Missouri terminals by 1 AM. Current CIGs are in the MVFR
range, though up stream obs show some IFR conditions under the
heavier rain. Expect activity to persist through sunrise as a little
surface low spins up and moves northeast Wednesday pushing the
storms off to north while allow surface winds to continue veering
around to the west by early afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...Cutter
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1156 PM CDT TUE APR 19 2016
.Discussion...
Issued at 310 PM CDT TUE APR 19 2016
Short Term (Today through Thursday night):
The main feature of interest in the short term continues to be the
upper level low out west. It is centered over northeastern Colorado
this afternoon. This low will continue to meander slowly eastward
tonight as it remains cut off from the upper level steering flow. It
will however take on a negative tilt this evening with an associated
vort max rotating around the base of the trough. This will help a
surface low to develop across eastern Kansas tonight. This will
provide for good forcing and expect showers to develop across
eastern Kansas tonight and spread northeastward across the area.
Despite good forcing, weak lapse rates and only a couple hundred
Joules of CAPE should limit thunderstorm activity however, isolated
storms can not be ruled out across northeastern Kansas and
northwestern Missouri. Tomorrow the upper level low will move into
the vicinity of the Missouri/Iowa border continuing showers and
isolated thunderstorm chances generally north of the Missouri River.
Cloud cover and precipitation will also keep temperatures in the low
to mid 60s across the northern CWA while temperatures across the
south will range into the lower 70s. The upper low will continue to
remain near stationary tomorrow night and will continue shower
chance tomorrow night. Thursday the upper level system finally gets
absorbed into the upper level flow north of the area. Residual
showers on the back side of the exiting upper level trough will
remain possible on Thursday before finally drying out Thursday night
as the upper level trough exits the region. Highs Thursday will
remain in the mid 60s to lower 70s.
Extended Range (Friday through Tuesday):
As the upper level system exits the region, upper level ridging over
the Rockies will begin to push eastward and begin to build into the
local area on Friday. This ridge will remain over the area through
Sunday providing warm temperatures for the upcoming weekend. Highs
by Sunday will rise into the upper 70s to lower 80s. On
Sunday/Sunday night another upper level low will move out from the
central Rockies into the northern Plains flattening the upper level
ridge and will force a cold front into the eastern Plains. This will
bring the next round of showers and thunderstorms to the area late
Sunday into Sunday night. Unsettled weather may then continue into
the beginning of next week as the upper level low weakens across the
northern Plains on Monday leaving the cold front stalled across the
CWA Monday into Tuesday continuing shower and thunderstorm chances.
&&
.Aviation...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1156 PM CDT TUE APR 19 2016
Rain is currently moving north and will have likely spread across all
the west Missouri terminals by 1 AM. Current CIGs are in the MVFR
range, though up stream obs show some IFR conditions under the
heavier rain. Expect activity to persist through sunrise as a little
surface low spins up and moves northeast Wednesday pushing the
storms off to north while allow surface winds to continue veering
around to the west by early afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...73
Aviation...Cutter
Area Forecast Discussion
National Weather Service Springfield MO
1150 PM CDT TUE APR 19 2016
.SHORT TERM...(This evening through Wednesday)
Issued at 243 PM CDT Tue Apr 19 2016
The slow moving upper low will continue to move eastward over the
next 24 hours and bring the potential for showers and isolated
thunderstorms to the Ozarks. Winds across the region will remain
southerly with temperatures falling into the 50`s tonight. May
need to watch for some very patchy fog again in the morning, but
coverage should be rather spotty as rain coverage should be
greater than last night.
Limited instability and little shear will significantly limit any
potential for strong or severe storms through Wednesday. An
Isolated rumble of thunder will likely be the most storms can
muster despite temperatures climbing into the upper 60s to lower
70s as the upper low begins to lift slowly to the northeast.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 243 PM CDT Tue Apr 19 2016
The upper low will continue to make its slow eastward progression
Wednesday night through Thursday night with the potential for
additional showers and isolated thunderstorms.
Despite the cloud cover and rain potential, temperatures will be
in the upper 40s into the 50s overnight and in the 70s during the
afternoons as we head into the weekend.
Upper level ridging will take control of the regions weather for
Friday and Saturday with highs climbing into the upper 70s with
sunny skies.
For the later half of the weekend however, the upper level flow
will become more southwesterly which will bring the return for
rain and storms chances for late Sunday night into the beginning
of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1147 PM CDT Tue Apr 19 2016
Still playing the IFR/MVFR game tonight with TAFS. Ceilings have
been up and down all evening and should settle in with mostly IFR
during the overinght. Not real hip on rain chances outside of JLN
and have gone with mainly VCSH wording early on. Models show most
of precipitation over northwest MO late tonight as energy lifts
northeast with the slow moving upper low.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Springfield MO
1150 PM CDT TUE APR 19 2016
.SHORT TERM...(This evening through Wednesday)
Issued at 243 PM CDT Tue Apr 19 2016
The slow moving upper low will continue to move eastward over the
next 24 hours and bring the potential for showers and isolated
thunderstorms to the Ozarks. Winds across the region will remain
southerly with temperatures falling into the 50`s tonight. May
need to watch for some very patchy fog again in the morning, but
coverage should be rather spotty as rain coverage should be
greater than last night.
Limited instability and little shear will significantly limit any
potential for strong or severe storms through Wednesday. An
Isolated rumble of thunder will likely be the most storms can
muster despite temperatures climbing into the upper 60s to lower
70s as the upper low begins to lift slowly to the northeast.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 243 PM CDT Tue Apr 19 2016
The upper low will continue to make its slow eastward progression
Wednesday night through Thursday night with the potential for
additional showers and isolated thunderstorms.
Despite the cloud cover and rain potential, temperatures will be
in the upper 40s into the 50s overnight and in the 70s during the
afternoons as we head into the weekend.
Upper level ridging will take control of the regions weather for
Friday and Saturday with highs climbing into the upper 70s with
sunny skies.
For the later half of the weekend however, the upper level flow
will become more southwesterly which will bring the return for
rain and storms chances for late Sunday night into the beginning
of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1147 PM CDT Tue Apr 19 2016
Still playing the IFR/MVFR game tonight with TAFS. Ceilings have
been up and down all evening and should settle in with mostly IFR
during the overinght. Not real hip on rain chances outside of JLN
and have gone with mainly VCSH wording early on. Models show most
of precipitation over northwest MO late tonight as energy lifts
northeast with the slow moving upper low.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...Lindenberg
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1149 PM CDT TUE APR 19 2016
.UPDATE...
Issued at 939 PM CDT Tue Apr 19 2016
Area of rain/embedded thunderstorms should continue to slowly
weaken and drift northward overnight tonight. Do not expect much
if any in the way of activity after midnight tonight. Next round
of at least scattered showers/storms will try and move
north/northeast from south-central/southeast Missouri early
Wednesday morning. Adjusted PoPs for the rest of tonight and also
raised low temperatures a couple of degrees in most locations due
to high dewpoints and clouds.
Gosselin
&&
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 06z TAFs through 06z Wednesday Night)
Issued at 1144 PM CDT Tue Apr 19 2016
Expect rest of tonight to be dry across terminals as rain/storms
have weakened and are dissipating currently across northeastern
Missouri. Some fog possible...particularly at KSUS and KCPS with
at least a partially clearing sky and low T/Td spreads. IFR visbys
not out of the question but for now went MVFR. Thinking there
should be enough clouds at KCOU and KUIN to preclude fog
development but this will have to be watched as well. Still
expecting some scattered showers and possibly a few storms to
affect metro terminals late Wednesay morning. Additional scattered
activity along/ahead of cold front will carry a higher threat of
thunder during the afternoon hours. By Wednesday evening...threat
of showers/storms should push off to the south and east of the
terminals with winds beginning to veer to the southwest as front
slowly moves through the bi-state area.
Specifics for KSTL:
Expecting dry/VFR conditions for rest of tonight. High T/Td spread
expected to prevent fog prevention. Scattered showers/possibly a
storm may affect terminal late morning. Then another break before
another round of showers/storms develops along/ahead of cold front
late afternoon. By Wednesday evening...threat of showers/storms
should push off to the east.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
941 PM CDT TUE APR 19 2016
.UPDATE...
Issued at 939 PM CDT Tue Apr 19 2016
Area of rain/embedded thunderstorms should continue to slowly
weaken and drift northward overnight tonight. Do not expect much
if any in the way of activity after midnight tonight. Next round
of at least scattered showers/storms will try and move
north/northeast from south-central/southeast Missouri early
Wednesday morning. Adjusted PoPs for the rest of tonight and also
raised low temperatures a couple of degrees in most locations due
to high dewpoints and clouds.
Gosselin
&&
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 643 PM CDT Tue Apr 19 2016
Main area of showers and thunderstorms along a frontal boundary
may affect the KUIN and KCOU terminals over the next couple of
hours. Showers and storms should gradually wane overnight with
most of the area dry. Area of showers and embedded storms look to
come toward the metro terminals Wednesday morning. Another round
along the actual cold front may affect all of the terminals during
the afternoon and possibly into the early evening hours.
Ceilings will also lower to MVFR on Wednesday as low-level
moisture increases.
Specifics for KSTL:
Expect a dry night with VFR conditions. Round of showers/embedded
storms expected to move in from south/southwest Wednesday morning.
Another round of showers/storms along cold front for Wednesday
afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
726 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 643 PM CDT Tue Apr 19 2016
Main area of showers and thunderstorms along a frontal boundary
may affect the KUIN and KCOU terminals over the next couple of
hours. Showers and storms should gradually wane overnight with
most of the area dry. Area of showers and embedded storms look to
come toward the metro terminals Wednesday morning. Another round
along the actual cold front may affect all of the terminals during
the afternoon and possibly into the early evening hours.
Ceilings will also lower to MVFR on Wednesday as low-level
moisture increases.
Specifics for KSTL:
Expect a dry night with VFR conditions. Round of showers/embedded
storms expected to move in from south/southwest Wednesday morning.
Another round of showers/storms along cold front for Wednesday
afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
726 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 643 PM CDT Tue Apr 19 2016
Main area of showers and thunderstorms along a frontal boundary
may affect the KUIN and KCOU terminals over the next couple of
hours. Showers and storms should gradually wane overnight with
most of the area dry. Area of showers and embedded storms look to
come toward the metro terminals Wednesday morning. Another round
along the actual cold front may affect all of the terminals during
the afternoon and possibly into the early evening hours.
Ceilings will also lower to MVFR on Wednesday as low-level
moisture increases.
Specifics for KSTL:
Expect a dry night with VFR conditions. Round of showers/embedded
storms expected to move in from south/southwest Wednesday morning.
Another round of showers/storms along cold front for Wednesday
afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
726 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 643 PM CDT Tue Apr 19 2016
Main area of showers and thunderstorms along a frontal boundary
may affect the KUIN and KCOU terminals over the next couple of
hours. Showers and storms should gradually wane overnight with
most of the area dry. Area of showers and embedded storms look to
come toward the metro terminals Wednesday morning. Another round
along the actual cold front may affect all of the terminals during
the afternoon and possibly into the early evening hours.
Ceilings will also lower to MVFR on Wednesday as low-level
moisture increases.
Specifics for KSTL:
Expect a dry night with VFR conditions. Round of showers/embedded
storms expected to move in from south/southwest Wednesday morning.
Another round of showers/storms along cold front for Wednesday
afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
726 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 643 PM CDT Tue Apr 19 2016
Main area of showers and thunderstorms along a frontal boundary
may affect the KUIN and KCOU terminals over the next couple of
hours. Showers and storms should gradually wane overnight with
most of the area dry. Area of showers and embedded storms look to
come toward the metro terminals Wednesday morning. Another round
along the actual cold front may affect all of the terminals during
the afternoon and possibly into the early evening hours.
Ceilings will also lower to MVFR on Wednesday as low-level
moisture increases.
Specifics for KSTL:
Expect a dry night with VFR conditions. Round of showers/embedded
storms expected to move in from south/southwest Wednesday morning.
Another round of showers/storms along cold front for Wednesday
afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
641 PM CDT TUE APR 19 2016
.Discussion...
Issued at 310 PM CDT TUE APR 19 2016
Short Term (Today through Thursday night):
The main feature of interest in the short term continues to be the
upper level low out west. It is centered over northeastern Colorado
this afternoon. This low will continue to meander slowly eastward
tonight as it remains cut off from the upper level steering flow. It
will however take on a negative tilt this evening with an associated
vort max rotating around the base of the trough. This will help a
surface low to develop across eastern Kansas tonight. This will
provide for good forcing and expect showers to develop across
eastern Kansas tonight and spread northeastward across the area.
Despite good forcing, weak lapse rates and only a couple hundred
Joules of CAPE should limit thunderstorm activity however, isolated
storms can not be ruled out across northeastern Kansas and
northwestern Missouri. Tomorrow the upper level low will move into
the vicinity of the Missouri/Iowa border continuing showers and
isolated thunderstorm chances generally north of the Missouri River.
Cloud cover and precipitation will also keep temperatures in the low
to mid 60s across the northern CWA while temperatures across the
south will range into the lower 70s. The upper low will continue to
remain near stationary tomorrow night and will continue shower
chance tomorrow night. Thursday the upper level system finally gets
absorbed into the upper level flow north of the area. Residual
showers on the back side of the exiting upper level trough will
remain possible on Thursday before finally drying out Thursday night
as the upper level trough exits the region. Highs Thursday will
remain in the mid 60s to lower 70s.
Extended Range (Friday through Tuesday):
As the upper level system exits the region, upper level ridging over
the Rockies will begin to push eastward and begin to build into the
local area on Friday. This ridge will remain over the area through
Sunday providing warm temperatures for the upcoming weekend. Highs
by Sunday will rise into the upper 70s to lower 80s. On
Sunday/Sunday night another upper level low will move out from the
central Rockies into the northern Plains flattening the upper level
ridge and will force a cold front into the eastern Plains. This will
bring the next round of showers and thunderstorms to the area late
Sunday into Sunday night. Unsettled weather may then continue into
the beginning of next week as the upper level low weakens across the
northern Plains on Monday leaving the cold front stalled across the
CWA Monday into Tuesday continuing shower and thunderstorm chances.
&&
.Aviation...(For the 00Z TAFS through 00Z Wednesday Evening)
Issued at 641 PM CDT TUE APR 19 2016
VFR conditions this evening are not expected to last as showers will
move northeast across the region late tonight into Wednesday morning.
Low end MVFR to IFR CIGs will spread across the terminals around
midnight along with scattered showers that will persist until around
sunrise Wednesday. Winds will veer around overnight to the south,
southwest and finally west by Wednesday afternoon as the center of a
small surface low, that brought the showers, moves northeast through
northwest Missouri. CIgs will likely go back to VFR for the
afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...73
Aviation...Cutter
Area Forecast Discussion
National Weather Service Springfield MO
600 PM CDT TUE APR 19 2016
.SHORT TERM...(This evening through Wednesday)
Issued at 243 PM CDT Tue Apr 19 2016
The slow moving upper low will continue to move eastward over the
next 24 hours and bring the potential for showers and isolated
thunderstorms to the Ozarks. Winds across the region will remain
southerly with temperatures falling into the 50`s tonight. May
need to watch for some very patchy fog again in the morning, but
coverage should be rather spotty as rain coverage should be
greater than last night.
Limited instability and little shear will significantly limit any
potential for strong or severe storms through Wednesday. An
Isolated rumble of thunder will likely be the most storms can
muster despite temperatures climbing into the upper 60s to lower
70s as the upper low begins to lift slowly to the northeast.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 243 PM CDT Tue Apr 19 2016
The upper low will continue to make its slow eastward progression
Wednesday night through Thursday night with the potential for
additional showers and isolated thunderstorms.
Despite the cloud cover and rain potential, temperatures will be
in the upper 40s into the 50s overnight and in the 70s during the
afternoons as we head into the weekend.
Upper level ridging will take control of the regions weather for
Friday and Saturday with highs climbing into the upper 70s with
sunny skies.
For the later half of the weekend however, the upper level flow
will become more southwesterly which will bring the return for
rain and storms chances for late Sunday night into the beginning
of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 557 PM CDT Tue Apr 19 2016
Pesky upper level low underneath blocking omega pattern still
sitting off to the west. Scattered showers will remain in the
terminals and mainly keeping in VCSH in the forecast. Main
aviation concern again will be with the MVFR/IFR conditions. Will
see ceilings lower again tonight, eventually into the IFR category
at the 3 terminal locations. Conditions will improve during the
day Wednesday, back into MVFR/VFR by late in the day.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Saint Louis MO
340 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1244 PM CDT Tue Apr 19 2016
A large upper level storm system centered over Colorado is sending
waves of smaller disturbances into the Mississippi Valley. Most of
the lower ceilings have risen at this time, and I expect VFR
ceilings and visibilities to prevail this afternoon and evening.
However...isolated to widely scattered showers may temporarily
lower the flight category to MVFR or even IFR in the heavier rain.
Coverage is uncertain, but best estimate at this time is 20-30
percent. Showers should dissipate slowly this evening after we
lose daytime heating. Think lower ceilings will develop again
Wednesday morning ahead of the surface trof of low pressure which
will move into the area toward the end of the period.
Additionally, more showers and probably thunderstorms as well are
expected to develop during the mid to late morning. IFR ceilings
are possible...but did not want to go that low until confidence
improves so have MVFR in all the terminal forecasts for Wednesday
morning.
Specifics for KSTL:
Expect VFR flight conditions to prevail at Lambert this afternoon
into the overnight period as well. Widely scattered showers are
developing over eastern Missouri. Looks like there are a couple
of stronger ones with some lighting in them now too. Unfortunately
there really aren`t any easily definable features to try to time
any precipitation at Lambert...something could develop over the
terminal with little or no warning. Fortunately the majority of
the showers should be brief and not particularly heavy. The most
likely impact would be a brief period of 3-5SM visibility. Showers
should dissipate slowly after sunset. MVFR looks likely tomorrow
morning ahead of a surface trof with scattered showers developing
after 12Z. Showers and thunderstorms are likely after 17Z.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Saint Louis MO
340 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late Tonight)
Issued at 340 PM CDT Tue Apr 19 2016
Large upper level low spinning over northeast Colorado will begin to
move slowly eastward tonight and pick up speed on Wednesday. Several
lobes of vorticity will rotate around the low tonight and Wednesday
which will continue to keep the threat for precip over the region. I
can`t say that there will be any time through 00Z Thursday that is
certain to be dry, but at least through mid morning the showers will
be more scattered in nature than wide-spread. The showers currently
on the scope should dissipate slowly this evening with a few likely
popping up at times across the CWFA through the night. Expect
increasing Increasing coverage during the late morning and afternoon
on Wednesday as 850mb winds veer to the southwest and one of the
more prominent vort-lobes rotates through Missouri into Illinois.
This combined with the 850mb moisture convergence and the associated
surface trof will likely touch off more widespread showers and
thunderstorms. Temperatures will be highly dependent on what areas
get precipitation. I stuck pretty close to ensemble MOS guidance
for lows tonight and highs Wednesday.
Carney
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 340 PM CDT Tue Apr 19 2016
A longwave upper-level RIDGE will dominate the central CONUS thru
the upcoming weekend.
The wx won`t be typical for a longwave RIDGE, however, because of
the presence of a cutoff LOW, that by the time Wednesday night rolls
around, will be in the process of being re-absorbed back into the
main flow and will be on the move.
The models still track the main system center to our north on
late Wednesday night and Thursday, leaving only the northern CWA
across northern MO and central IL with any measure of upper support
for pcpn. There will also be a surface cold front slowly dropping
thru Thursday that will maintain lift and focus. So, rain chances
will continue easily thru Thursday.
The more significant drying of the column and subsequent reduction
in rain chances should arrive with passage of the TROF axis late
Thursday, but even with this, there is some model discrepancy on
timing, with the GEM delaying this until early Friday morning, but
the mode amongst the solutions favors late Thursday afternoon or
early evening. Temps will temporarily dip back to near normal for
late week between the clouds, rain, and brief intrusion of a cooler
airmass behind the Thursday front.
The departure of the leftover cutoff LOW system which should be by
Friday will mean a more typical result for a longwave upper RIDGE--
and back to dry and warm wx for the weekend for most areas once the
southerly winds kick back in on Saturday. Daytime max temps
should reach near 80F again.
The GFS has since backed off its adverisement of a strong upper level
system for next Monday, but both the EC and GFS now at least show a
favorable setup for what should be a frontal boundary dropping south
into our region for late Monday into Tuesday with a supportive flow
aloft from the W-NW. So despite losing what would have been good
upper support, the signal for rain chances is no less good late
Monday and Tuesday than it was 24hrs ago, and largely maintained the
at or slightly above average climo PoPs during this period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1244 PM CDT Tue Apr 19 2016
A large upper level storm system centered over Colorado is sending
waves of smaller disturbances into the Mississippi Valley. Most of
the lower ceilings have risen at this time, and I expect VFR
ceilings and visibilities to prevail this afternoon and evening.
However...isolated to widely scattered showers may temporarily
lower the flight category to MVFR or even IFR in the heavier rain.
Coverage is uncertain, but best estimate at this time is 20-30
percent. Showers should dissipate slowly this evening after we
lose daytime heating. Think lower ceilings will develop again
Wednesday morning ahead of the surface trof of low pressure which
will move into the area toward the end of the period.
Additionally, more showers and probably thunderstorms as well are
expected to develop during the mid to late morning. IFR ceilings
are possible...but did not want to go that low until confidence
improves so have MVFR in all the terminal forecasts for Wednesday
morning.
Specifics for KSTL:
Expect VFR flight conditions to prevail at Lambert this afternoon
into the overnight period as well. Widely scattered showers are
developing over eastern Missouri. Looks like there are a couple
of stronger ones with some lighting in them now too. Unfortunately
there really aren`t any easily definable features to try to time
any precipitation at Lambert...something could develop over the
terminal with little or no warning. Fortunately the majority of
the showers should be brief and not particularly heavy. The most
likely impact would be a brief period of 3-5SM visibility. Showers
should dissipate slowly after sunset. MVFR looks likely tomorrow
morning ahead of a surface trof with scattered showers developing
after 12Z. Showers and thunderstorms are likely after 17Z.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
310 PM CDT TUE APR 19 2016
.Discussion...
Issued at 310 PM CDT TUE APR 19 2016
Short Term (Today through Thursday night):
The main feature of interest in the short term continues to be the
upper level low out west. It is centered over northeastern Colorado
this afternoon. This low will continue to meander slowly eastward
tonight as it remains cut off from the upper level steering flow. It
will however take on a negative tilt this evening with an associated
vort max rotating around the base of the trough. This will help a
surface low to develop across eastern Kansas tonight. This will
provide for good forcing and expect showers to develop across
eastern Kansas tonight and spread northeastward across the area.
Despite good forcing, weak lapse rates and only a couple hundred
Joules of CAPE should limit thunderstorm activity however, isolated
storms can not be ruled out across northeastern Kansas and
northwestern Missouri. Tomorrow the upper level low will move into
the vicinity of the Missouri/Iowa border continuing showers and
isolated thunderstorm chances generally north of the Missouri River.
Cloud cover and precipitation will also keep temperatures in the low
to mid 60s across the northern CWA while temperatures across the
south will range into the lower 70s. The upper low will continue to
remain near stationary tomorrow night and will continue shower
chance tomorrow night. Thursday the upper level system finally gets
absorbed into the upper level flow north of the area. Residual
showers on the back side of the exiting upper level trough will
remain possible on Thursday before finally drying out Thursday night
as the upper level trough exits the region. Highs Thursday will
remain in the mid 60s to lower 70s.
Extended Range (Friday through Tuesday):
As the upper level system exits the region, upper level ridging over
the Rockies will begin to push eastward and begin to build into the
local area on Friday. This ridge will remain over the area through
Sunday providing warm temperatures for the upcoming weekend. Highs
by Sunday will rise into the upper 70s to lower 80s. On
Sunday/Sunday night another upper level low will move out from the
central Rockies into the northern Plains flattening the upper level
ridge and will force a cold front into the eastern Plains. This will
bring the next round of showers and thunderstorms to the area late
Sunday into Sunday night. Unsettled weather may then continue into
the beginning of next week as the upper level low weakens across the
northern Plains on Monday leaving the cold front stalled across the
CWA Monday into Tuesday continuing shower and thunderstorm chances.
&&
.Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1222 PM CDT TUE APR 19 2016
Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the
TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will
prevail til tonight when showers will move into the terminals
around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z
window. Isold thunder will be poss with good forcing but time of day
and weak lapse rates should limit thunder chances. Consequently, have
left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow
morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier
showers.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...73
Aviation...73
Area Forecast Discussion
National Weather Service Springfield MO
243 PM CDT TUE APR 19 2016
.SHORT TERM...(This evening through Wednesday)
Issued at 243 PM CDT Tue Apr 19 2016
The slow moving upper low will continue to move eastward over the
next 24 hours and bring the potential for showers and isolated
thunderstorms to the Ozarks. Winds across the region will remain
southerly with temperatures falling into the 50`s tonight. May
need to watch for some very patchy fog again in the morning, but
coverage should be rather spotty as rain coverage should be
greater than last night.
Limited instability and little shear will significantly limit any
potential for strong or severe storms through Wednesday. An
Isolated rumble of thunder will likely be the most storms can
muster despite temperatures climbing into the upper 60s to lower
70s as the upper low begins to lift slowly to the northeast.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 243 PM CDT Tue Apr 19 2016
The upper low will continue to make its slow eastward progression
Wednesday night through Thursday night with the potential for
additional showers and isolated thunderstorms.
Despite the cloud cover and rain potential, temperatures will be
in the upper 40s into the 50s overnight and in the 70s during the
afternoons as we head into the weekend.
Upper level ridging will take control of the regions weather for
Friday and Saturday with highs climbing into the upper 70s with
sunny skies.
For the later half of the weekend however, the upper level flow
will become more southwesterly which will bring the return for
rain and storms chances for late Sunday night into the beginning
of next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1234 PM CDT Tue Apr 19 2016
Off and on shower activity can be expected again through this TAF
cycle. Visibilities have improved from early this morning,
however, ceilings have been behaving a tad erratic. Ceiling
heights will be the primary challenge through the next 24 hours as
all terminals will alternate between IFR and MVFR conditions at
times. There may even been some brief VFR mixed in this afternoon
as some breaks in the cloud cover have been observed from time to
time on satellite imagery.
Fog/low stratus may once again impact the forecast tomorrow,
though, the signal isn`t nearly as strong as yesterday`s. Still,
enough confidence is there to lower visibilities down to the MVFR
range briefly Wednesday morning. Winds will continue to be light
and variable through the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...Frye
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
111 PM CDT TUE APR 19 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 323 AM CDT Tue Apr 19 2016
Water vapor imagery depicting a well defined conveyor belt of
moisture flowing into the region as a result of deep layered
south-southwesterly flow well ahead of the Rockies upper low. An
initial low amplitude impulse in the flow aloft is contributing to
a broken swath of rain/showers through central and northeast MO.
This precipitation should continue a north-northeast movement this
morning shunting to the east and gradually weakening. There may
be a good bit of downtime then from mid-morning into early
afternoon where any precipitation is spotty. However from mid-late
afternoon the diffuse boundary and weak convergence zone
stretching across central and northeast MO is expected to become
the focus for scattered showers and thunderstorms as diurnal
heating results in a weakly unstable and uncapped air mass.
Glass
.LONG TERM... (Tonight through Monday)
Issued at 323 AM CDT Tue Apr 19 2016
Showers and thunderstorms originating this afternoon are expected
to dissipate by mid-evening once instability wanes and also given
the overall weak forcing. Once again there may then be a good deal
of dry time with only spotty precipitation until well overnight.
At that time a rather prominent short wave trof will begin
spreading large scale ascent from western MO into central MO as it
rotates northeastward in advance of the slowly migrating upper
low. Precipitation chances will ramp-up Wednesday into Wednesday
evening as the aforementioned short wave continues to rotate to
the northeast producing large scale ascent, as the low level
southerly flow/WAA increases, and as the accompanying surface low
and frontal system moves into the region. The precipitation threat
should then diminish overnight as the upper trof becomes more
positively tilted and migratory, and as deeper moisture is
transported into the OH/TN Valleys in advance of the advancing
surface cold front.
There will remain a threat of scattered showers on Thursday in the
post-frontal cyclonic flow and until the passage of the upper trof
axis to the east.
High pressure should dominate on Friday bringing tranquil weather
and seasonable temperatures. The high will then begin retreating
Saturday bringing some moderation, with a bigger warm-up on Sunday
as ridging aloft progresses into the MS valley from the Plains and
low level southerly flow/WAA gets well established. Lot of
uncertainty beyond Sunday with some large pattern differences
amongst the deterministic models and large spreads in the EPS. In
general however an increasing threat of stormy conditions seems to
be the trend.
Glass
&&
.AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1244 PM CDT Tue Apr 19 2016
A large upper level storm system centered over Colorado is sending
waves of smaller disturbances into the Mississippi Valley. Most of
the lower ceilings have risen at this time, and I expect VFR
ceilings and visibilities to prevail this afternoon and evening.
However...isolated to widely scattered showers may temporarily
lower the flight category to MVFR or even IFR in the heavier rain.
Coverage is uncertain, but best estimate at this time is 20-30
percent. Showers should dissipate slowly this evening after we
lose daytime heating. Think lower ceilings will develop again
Wednesday morning ahead of the surface trof of low pressure which
will move into the area toward the end of the period.
Additionally, more showers and probably thunderstorms as well are
expected to develop during the mid to late morning. IFR ceilings
are possible...but did not want to go that low until confidence
improves so have MVFR in all the terminal forecasts for Wednesday
morning.
Specifics for KSTL:
Expect VFR flight conditions to prevail at Lambert this afternoon
into the overnight period as well. Widely scattered showers are
developing over eastern Missouri. Looks like there are a couple
of stronger ones with some lighting in them now too. Unfortunately
there really aren`t any easily definable features to try to time
any precipitation at Lambert...something could develop over the
terminal with little or no warning. Fortunately the majority of
the showers should be brief and not particularly heavy. The most
likely impact would be a brief period of 3-5SM visibility. Showers
should dissipate slowly after sunset. MVFR looks likely tomorrow
morning ahead of a surface trof with scattered showers developing
after 12Z. Showers and thunderstorms are likely after 17Z.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
1234 PM CDT TUE APR 19 2016
...18z Aviation Update...
.SHORT TERM...(Today through Wednesday Night)
Issued at 245 AM CDT Tue Apr 19 2016
Moist and unsettled weather conditions will be the story the next
couple of days as the upper low positioned over the southern
Rockies begins a slow eastward progression. Meanwhile a diffuse
frontal boundary remain nearly stalled from north central Oklahoma
into northern Missouri. A broad region of upper level divergence
superimposed over at least weak low level convergence near the
front along with a continued moisture advection will support
scattered to numerous showers today.
After a lull this evening we could see an increase in the
coverage of showers later tonight into Wednesday as a shortwave
swings northeast from the southern Plains ahead of the upper low.
While most everyone will see rainfall the potential for heavy rain
has decreased from previous forecast due to the lack of strong
deep synoptic scale lift and limited instability. This lack of
instability will limit the coverage of thunderstorms with just
isolated embedded thunder expected.
.LONG TERM...(Thursday through Monday)
Issued at 245 AM CDT Tue Apr 19 2016
The upper low will begin to open up and move steadily east during
late week. The chance for isolated to scattered showers will
linger Thursday as the upper level trough axis swings across the
region.
Upper level ridging will build into the region heading into Friday
and this weekend following the passage of the upper level trough.
Building 500 MB heights and return southerly flow will push
temperatures well into the 70s if not near the 80 degree mark this
weekend.
Models continue to show a more unsettled weather pattern returning
next week but details yet to be determined.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1234 PM CDT Tue Apr 19 2016
Off and on shower activity can be expected again through this TAF
cycle. Visibilities have improved from early this morning,
however, ceilings have been behaving a tad erratic. Ceiling
heights will be the primary challenge through the next 24 hours as
all terminals will alternate between IFR and MVFR conditions at
times. There may even been some brief VFR mixed in this afternoon
as some breaks in the cloud cover have been observed from time to
time on satellite imagery.
Fog/low stratus may once again impact the forecast tomorrow,
though, the signal isn`t nearly as strong as yesterday`s. Still,
enough confidence is there to lower visibilities down to the MVFR
range briefly Wednesday morning. Winds will continue to be light
and variable through the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Frye
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1222 PM CDT TUE APR 19 2016
.Discussion...
Issued at 254 AM CDT TUE APR 19 2016
Large closed low slowly drifting into the High Plains remains the
main weather story for the next few days, as this system will
continue to push several more rounds of rain into the region.
For today, a weak cold front is becoming quasi-stationary near the
southern and eastern borders of our forecast area, and this feature
will be the primary focus for any rainfall through most of the
afternoon. This will keep the higher precipitation chances focused
across the Clinton/Sedalia areas and then up the US-63 corridor.
Areas further west should stay dry most the day with a few peeks of
sun possible.
Rainfall chances increase significantly later tonight when most
models agree that a fairly strong and negatively-tilted shortwave
will round the base of the mean upper low and eject into our area.
This will likely lead to small-scale cyclogenesis over northeast KS,
with resulting lift bringing a large area of rain to eastern KS and
western MO late tonight. A focused area of convergence/frontogenesis
near the surface low combined with precipitable water values between
an inch and an inch and a half could favor some modest rainfall
amounts, particularly from eastern KS into northwest MO where some
areas could see an inch or more of rain from this system. Most
precipitation will taper off Weds afternoon as the surface low tracks
into Iowa, though a few showers or storms could linger into central
MO along a trailing front.
Large upper low will finally begin to push east of the region on
Thursday when it will merge with the northern jet stream and phase
into a broad, progressive upper wave. A few showers are possible
Thursday on the back side of this system, otherwise the departure of
the upper low will finally allow for drying conditions heading into
Friday and Saturday. Deep upper ridging building in behind this
system will bring a warming trend into the weekend with several areas
pushing 80 degrees by Sunday.
&&
.Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1222 PM CDT TUE APR 19 2016
Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the
TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will
prevail til tonight when showers will move into the terminals
around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z
window. Isold thunder will be poss with good forcing but time of day
and weak lapse rates should limit thunder chances. Consequently, have
left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow
morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier
showers.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...73
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
631 AM CDT TUE APR 19 2016
.Discussion...
Issued at 254 AM CDT TUE APR 19 2016
Large closed low slowly drifting into the High Plains remains the
main weather story for the next few days, as this system will
continue to push several more rounds of rain into the region.
For today, a weak cold front is becoming quasi-stationary near the
southern and eastern borders of our forecast area, and this feature
will be the primary focus for any rainfall through most of the
afternoon. This will keep the higher precipitation chances focused
across the Clinton/Sedalia areas and then up the US-63 corridor.
Areas further west should stay dry most the day with a few peeks of
sun possible.
Rainfall chances increase significantly later tonight when most
models agree that a fairly strong and negatively-tilted shortwave
will round the base of the mean upper low and eject into our area.
This will likely lead to small-scale cyclogenesis over northeast KS,
with resulting lift bringing a large area of rain to eastern KS and
western MO late tonight. A focused area of convergence/frontogenesis
near the surface low combined with precipitable water values between
an inch and an inch and a half could favor some modest rainfall
amounts, particularly from eastern KS into northwest MO where some
areas could see an inch or more of rain from this system. Most
precipitation will taper off Weds afternoon as the surface low tracks
into Iowa, though a few showers or storms could linger into central
MO along a trailing front.
Large upper low will finally begin to push east of the region on
Thursday when it will merge with the northern jet stream and phase
into a broad, progressive upper wave. A few showers are possible
Thursday on the back side of this system, otherwise the departure of
the upper low will finally allow for drying conditions heading into
Friday and Saturday. Deep upper ridging building in behind this
system will bring a warming trend into the weekend with several areas
pushing 80 degrees by Sunday.
&&
.Aviation...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 631 AM CDT TUE APR 19 2016
Most shower activity today will be confined to central and eastern
Missouri, with the KC and STJ areas remaining dry for much of the
day. MVFR ceilings are gradually lifting to VFR across eastern KS,
and expect this trend to continue into western MO through the
morning. Widespread rain will overspread the region late tonight.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...Hawblitzel
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
631 AM CDT TUE APR 19 2016
.Discussion...
Issued at 254 AM CDT TUE APR 19 2016
Large closed low slowly drifting into the High Plains remains the
main weather story for the next few days, as this system will
continue to push several more rounds of rain into the region.
For today, a weak cold front is becoming quasi-stationary near the
southern and eastern borders of our forecast area, and this feature
will be the primary focus for any rainfall through most of the
afternoon. This will keep the higher precipitation chances focused
across the Clinton/Sedalia areas and then up the US-63 corridor.
Areas further west should stay dry most the day with a few peeks of
sun possible.
Rainfall chances increase significantly later tonight when most
models agree that a fairly strong and negatively-tilted shortwave
will round the base of the mean upper low and eject into our area.
This will likely lead to small-scale cyclogenesis over northeast KS,
with resulting lift bringing a large area of rain to eastern KS and
western MO late tonight. A focused area of convergence/frontogenesis
near the surface low combined with precipitable water values between
an inch and an inch and a half could favor some modest rainfall
amounts, particularly from eastern KS into northwest MO where some
areas could see an inch or more of rain from this system. Most
precipitation will taper off Weds afternoon as the surface low tracks
into Iowa, though a few showers or storms could linger into central
MO along a trailing front.
Large upper low will finally begin to push east of the region on
Thursday when it will merge with the northern jet stream and phase
into a broad, progressive upper wave. A few showers are possible
Thursday on the back side of this system, otherwise the departure of
the upper low will finally allow for drying conditions heading into
Friday and Saturday. Deep upper ridging building in behind this
system will bring a warming trend into the weekend with several areas
pushing 80 degrees by Sunday.
&&
.Aviation...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 631 AM CDT TUE APR 19 2016
Most shower activity today will be confined to central and eastern
Missouri, with the KC and STJ areas remaining dry for much of the
day. MVFR ceilings are gradually lifting to VFR across eastern KS,
and expect this trend to continue into western MO through the
morning. Widespread rain will overspread the region late tonight.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
558 AM CDT TUE APR 19 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 323 AM CDT Tue Apr 19 2016
Water vapor imagery depicting a well defined conveyor belt of
moisture flowing into the region as a result of deep layered
south-southwesterly flow well ahead of the Rockies upper low. An
initial low amplitude impulse in the flow aloft is contributing to
a broken swath of rain/showers through central and northeast MO.
This precipitation should continue a north-northeast movement this
morning shunting to the east and gradually weakening. There may
be a good bit of downtime then from mid-morning into early
afternoon where any precipitation is spotty. However from mid-late
afternoon the diffuse boundary and weak convergence zone
stretching across central and northeast MO is expected to become
the focus for scattered showers and thunderstorms as diurnal
heating results in a weakly unstable and uncapped air mass.
Glass
.LONG TERM... (Tonight through Monday)
Issued at 323 AM CDT Tue Apr 19 2016
Showers and thunderstorms originating this afternoon are expected
to dissipate by mid-evening once instability wanes and also given
the overall weak forcing. Once again there may then be a good deal
of dry time with only spotty precipitation until well overnight.
At that time a rather prominent short wave trof will begin
spreading large scale ascent from western MO into central MO as it
rotates northeastward in advance of the slowly migrating upper
low. Precipitation chances will ramp-up Wednesday into Wednesday
evening as the aforementioned short wave continues to rotate to
the northeast producing large scale ascent, as the low level
southerly flow/WAA increases, and as the accompanying surface low
and frontal system moves into the region. The precipitation threat
should then diminish overnight as the upper trof becomes more
postively tilted and migratory, and as deeper moisture is transported
into the OH/TN Valleys in advance of the advancing surface cold
front.
There will remain a threat of scattered showers on Thursday in the
post-frontal cyclonic flow and until the passage of the upper trof
axis to the east.
High pressure should dominate on Friday bringing tranquil weather
and seasonable temperatures. The high will then begin retreating
Saturday bringing some moderation, with a bigger warm-up on Sunday
as ridging aloft progresses into the MS valley from the Plains and
low level southerly flow/WAA gets well established. Lot of
uncertainty beyond Sunday with some large pattern differences
amongst the deterministic models and large spreads in the EPS. In
general however an increasing threat of stormy conditions seems to
be the trend.
Glass
&&
.AVIATION... (For the 12z TAFs through 12z Wednesday Morning)
Issued at 549 AM CDT Tue Apr 19 2016
Band of light rain from near KCOU to KUIN will gradually dissipate
this morning. Additional light showers and isolated thunderstorms
are possible this afternoon...but sparse coverage precludes
placing in TAFS. Ceilings will remain in the VFR category...with
generally light and variable winds.
Specifics for KSTL: Band of light rain this morning should stay
west of KSTL metro...and ceilings will likely remain above 7000
feet for the duration of this TAF period. There is a chance for
scattered showers and isolated thunderstorms this afternoon...but
coverage is expected to remain sparse. Winds will remain light
southwest to south.
Browning
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
549 AM CDT TUE APR 19 2016
...Update to Aviation Discussion for 12Z TAFS...
.SHORT TERM...(Today through Wednesday Night)
Issued at 245 AM CDT Tue Apr 19 2016
Moist and unsettled weather conditions will be the story the next
couple of days as the upper low positioned over the southern
Rockies begins a slow eastward progression. Meanwhile a diffuse
frontal boundary remain nearly stalled from north central Oklahoma
into northern Missouri. A broad region of upper level divergence
superimposed over at least weak low level convergence near the
front along with a continued moisture advection will support
scattered to numerous showers today.
After a lull this evening we could see an increase in the
coverage of showers later tonight into Wednesday as a shortwave
swings northeast from the southern Plains ahead of the upper low.
While most everyone will see rainfall the potential for heavy rain
has decreased from previous forecast due to the lack of strong
deep synoptic scale lift and limited instability. This lack of
instability will limit the coverage of thunderstorms with just
isolated embedded thunder expected.
.LONG TERM...(Thursday through Monday)
Issued at 245 AM CDT Tue Apr 19 2016
The upper low will begin to open up and move steadily east during
late week. The chance for isolated to scattered showers will
linger Thursday as the upper level trough axis swings across the
region.
Upper level ridging will build into the region heading into Friday
and this weekend following the passage of the upper level trough.
Building 500 MB heights and return southerly flow will push
temperatures well into the 70s if not near the 80 degree mark this
weekend.
Models continue to show a more unsettled weather pattern returning
next week but details yet to be determined.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 543 AM CDT Tue Apr 19 2016
For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will continue at
the KJLN TAF site early this morning, then will improve through
the day. Ceilings may lower into the MVFR range at the KSGF and
KBBG TAF sites this morning before improving this afternoon.
Patchy fog will also occur early this morning, especially at the
KBBG site.
Showers should remain north and south of the TAF sites through
this morning, then scattered showers will be possible this
afternoon into tonight across the area.
Ceilings are expected to lower into the MVFR to IFR range again
tonight into early Wednesday morning.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Wise
Area Forecast Discussion
National Weather Service Saint Louis MO
349 AM CDT TUE APR 19 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 323 AM CDT Tue Apr 19 2016
Water vapor imagery depicting a well defined conveyor belt of
moisture flowing into the region as a result of deep layered
south-southwesterly flow well ahead of the Rockies upper low. An
initial low amplitude impulse in the flow aloft is contributing to
a broken swath of rain/showers through central and northeast MO.
This precipitation should continue a north-northeast movement this
morning shunting to the east and gradually weakening. There may
be a good bit of downtime then from mid-morning into early
afternoon where any precipitation is spotty. However from mid-late
afternoon the diffuse boundary and weak convergence zone
stretching across central and northeast MO is expected to become
the focus for scattered showers and thunderstorms as diurnal
heating results in a weakly unstable and uncapped air mass.
Glass
.LONG TERM... (Tonight through Monday)
Issued at 323 AM CDT Tue Apr 19 2016
Showers and thunderstorms originating this afternoon are expected
to dissipate by mid-evening once instability wanes and also given
the overall weak forcing. Once again there may then be a good deal
of dry time with only spotty precipitation until well overnight.
At that time a rather prominent short wave trof will begin
spreading large scale ascent from western MO into central MO as it
rotates northeastward in advance of the slowly migrating upper
low. Precipitation chances will ramp-up Wednesday into Wednesday
evening as the aforementioned short wave continues to rotate to
the northeast producing large scale ascent, as the low level
southerly flow/WAA increases, and as the accompanying surface low
and frontal system moves into the region. The precipitation threat
should then diminish overnight as the upper trof becomes more
postively tilted and migratory, and as deeper moisture is transported
into the OH/TN Valleys in advance of the advancing surface cold
front.
There will remain a threat of scattered showers on Thursday in the
post-frontal cyclonic flow and until the passage of the upper trof
axis to the east.
High pressure should dominate on Friday bringing tranquil weather
and seasonable temperatures. The high will then begin retreating
Saturday bringing some moderation, with a bigger warm-up on Sunday
as ridging aloft progresses into the MS valley from the Plains and
low level southerly flow/WAA gets well established. Lot of
uncertainty beyond Sunday with some large pattern differences
amongst the deterministic models and large spreads in the EPS. In
general however an increasing threat of stormy conditions seems to
be the trend.
Glass
&&
.AVIATION... (For the 06z TAFs through 06z Tuesday Night)
Issued at 1133 PM CDT Mon Apr 18 2016
Scattered showers will affect KCOU and possibly KUIN through the
rest of tonight. Showers should be light and likely not pose
visibility issues. For the metro terminals...showers should stay
west. Ceilings will also lower at KCOU and KUIN into MVFR later on
tonight. Some minor visibility reduction is also possible in fog
at KCOU. For Tuesday...highest threat of showers/storms again from
KCOU to KUIN with the best chance of convection during the late
afternoon and early evening hours. Heavier showers/storms could dip visibilities
down briefly into IFR. Metro terminals again likely too far to
the east.
Specifics for KSTL:
Lion`s share of shower/thunderstorm activity expected to stay west
of terminal through Tuesday night. However...scattered
showers/storms are possible Tuesday afternoon/evening in
particular. Continue to leave out prevailing group as chances look
higher further to the west. Winds will remain light/variable
before turning southeasterly again Tuesday afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
258 AM CDT TUE APR 19 2016
...Good Chance for Showers Today through Wednesday...
.SHORT TERM...(Today through Wednesday Night)
Issued at 245 AM CDT Tue Apr 19 2016
Moist and unsettled weather conditions will be the story the next
couple of days as the upper low positioned over the southern
Rockies begins a slow eastward progression. Meanwhile a diffuse
frontal boundary remain nearly stalled from north central Oklahoma
into northern Missouri. A broad region of upper level divergence
superimposed over at least weak low level convergence near the
front along with a continued moisture advection will support
scattered to numerous showers today.
After a lull this evening we could see an increase in the
coverage of showers later tonight into Wednesday as a shortwave
swings northeast from the southern Plains ahead of the upper low.
While most everyone will see rainfall the potential for heavy rain
has decreased from previous forecast due to the lack of strong
deep synoptic scale lift and limited instability. This lack of
instability will limit the coverage of thunderstorms with just
isolated embedded thunder expected.
.LONG TERM...(Thursday through Monday)
Issued at 245 AM CDT Tue Apr 19 2016
The upper low will begin to open up and move steadily east during
late week. The chance for isolated to scattered showers will
linger Thursday as the upper level trough axis swings across the
region.
Upper level ridging will build into the region heading into Friday
and this weekend following the passage of the upper level trough.
Building 500 MB heights and return southerly flow will push
temperatures well into the 70s if not near the 80 degree mark this
weekend.
Models continue to show a more unsettled weather pattern returning
next week but details yet to be determined.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1132 PM CDT Mon Apr 18 2016
Scattered light showers across the area this evening and have
affected the terminal locations with some light rain. While
showers will be in the vicinity of the aviation sites tonight and
Tue morning, the main concern will be with MVFR and IFR
conditions. Will see ceilings deteriorate overnight and may build
down enough for visibilities to also be affected. Showers will
again become more numerous late in the period as the upper level
shortwave to the west slowly approaches.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Foster
LONG TERM...Foster
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
254 AM CDT TUE APR 19 2016
.Discussion...
Issued at 254 AM CDT TUE APR 19 2016
Large closed low slowly drifting into the High Plains remains the
main weather story for the next few days, as this system will
continue to push several more rounds of rain into the region.
For today, a weak cold front is becoming quasi-stationary near the
southern and eastern borders of our forecast area, and this feature
will be the primary focus for any rainfall through most of the
afternoon. This will keep the higher precipitation chances focused
across the Clinton/Sedalia areas and then up the US-63 corridor.
Areas further west should stay dry most the day with a few peeks of
sun possible.
Rainfall chances increase significantly later tonight when most
models agree that a fairly strong and negatively-tilted shortwave
will round the base of the mean upper low and eject into our area.
This will likely lead to small-scale cyclogenesis over northeast KS,
with resulting lift bringing a large area of rain to eastern KS and
western MO late tonight. A focused area of convergence/frontogenesis
near the surface low combined with precipitable water values between
an inch and an inch and a half could favor some modest rainfall
amounts, particularly from eastern KS into northwest MO where some
areas could see an inch or more of rain from this system. Most
precipitation will taper off Weds afternoon as the surface low tracks
into Iowa, though a few showers or storms could linger into central
MO along a trailing front.
Large upper low will finally begin to push east of the region on
Thursday when it will merge with the northern jet stream and phase
into a broad, progressive upper wave. A few showers are possible
Thursday on the back side of this system, otherwise the departure of
the upper low will finally allow for drying conditions heading into
Friday and Saturday. Deep upper ridging building in behind this
system will bring a warming trend into the weekend with several areas
pushing 80 degrees by Sunday.
&&
.Aviation...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1153 PM CDT MON APR 18 2016
Scattered showers have moved out of west central and northwest MO and
will gradually shift east overnight. Extensive area of MVFR ceilings
will likely remain intact over northern, west central and central MO
overnight. Satellite imagery does show the clearing line over central
KS shifting east and projects to reach the MO/KS border around 12z.
These clouds will then be replaced by broken VFR ceilings for most of
Tuesday. Should start to see scattered convection form or move into
west central MO and east central KS by late Tuesday evening.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...MJ
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
254 AM CDT TUE APR 19 2016
.Discussion...
Issued at 254 AM CDT TUE APR 19 2016
Large closed low slowly drifting into the High Plains remains the
main weather story for the next few days, as this system will
continue to push several more rounds of rain into the region.
For today, a weak cold front is becoming quasi-stationary near the
southern and eastern borders of our forecast area, and this feature
will be the primary focus for any rainfall through most of the
afternoon. This will keep the higher precipitation chances focused
across the Clinton/Sedalia areas and then up the US-63 corridor.
Areas further west should stay dry most the day with a few peeks of
sun possible.
Rainfall chances increase significantly later tonight when most
models agree that a fairly strong and negatively-tilted shortwave
will round the base of the mean upper low and eject into our area.
This will likely lead to small-scale cyclogenesis over northeast KS,
with resulting lift bringing a large area of rain to eastern KS and
western MO late tonight. A focused area of convergence/frontogenesis
near the surface low combined with precipitable water values between
an inch and an inch and a half could favor some modest rainfall
amounts, particularly from eastern KS into northwest MO where some
areas could see an inch or more of rain from this system. Most
precipitation will taper off Weds afternoon as the surface low tracks
into Iowa, though a few showers or storms could linger into central
MO along a trailing front.
Large upper low will finally begin to push east of the region on
Thursday when it will merge with the northern jet stream and phase
into a broad, progressive upper wave. A few showers are possible
Thursday on the back side of this system, otherwise the departure of
the upper low will finally allow for drying conditions heading into
Friday and Saturday. Deep upper ridging building in behind this
system will bring a warming trend into the weekend with several areas
pushing 80 degrees by Sunday.
&&
.Aviation...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1153 PM CDT MON APR 18 2016
Scattered showers have moved out of west central and northwest MO and
will gradually shift east overnight. Extensive area of MVFR ceilings
will likely remain intact over northern, west central and central MO
overnight. Satellite imagery does show the clearing line over central
KS shifting east and projects to reach the MO/KS border around 12z.
These clouds will then be replaced by broken VFR ceilings for most of
Tuesday. Should start to see scattered convection form or move into
west central MO and east central KS by late Tuesday evening.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Hawblitzel
Aviation...MJ
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1153 PM CDT MON APR 18 2016
.Discussion...
Issued at 332 PM CDT MON APR 18 2016
Water vapor imagery and H5 heights indicate the extensive closed low
still positioned over the inter-mountain west with cold front
currently moving through eastern Nebraska and Kansas, extending down
into the Texas panhandle. At the regional level, band of heavier
precip has moved northeastward through the morning and early
afternoon, gradually weakening with time as primary forcing remained
north across Iowa. Scattered showers remain on the backside of the
main band, and the HRRR has done a great job with the overall precip
trend. With a few hundred joules of CAPE, might see an isolated
thunderstorm or two with this scattered activity. Western half of
the CWA should see a downward trend in activity towards evening.
Another vorticity maxima will peel off from the main low late
tonight into Tuesday morning. Cold front looks to stall across the
region from southwest to northeast Missouri. Greater chances for
precip will focus near this diffuse cold front and with 600-800 J/kg
of CAPE forecast Tuesday afternoon, expect to see thunderstorm
development by early afternoon. Showers and thunderstorms expected
once again Wednesday in somewhat of a wash-rinse-repeat cycle. Upper
low finally begins to eject into the Plains Tuesday night into
Wednesday, eventually merging into the northern stream flow. As the
trough passes to the north of the region, we could see a few more
showers and thunderstorms into Thursday.
Upper level ridging will build into the central conus as we head
into the weekend, bringing warm temperatures and relatively quiet
weather. The next system to watch will be a trough ejecting out of
the central Rockies the beginning of the next work week.
&&
.Aviation...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1153 PM CDT MON APR 18 2016
Scattered showers have moved out of west central and northwest MO and
will gradually shift east overnight. Extensive area of MVFR ceilings
will likely remain intact over northern, west central and central MO
overnight. Satellite imagery does show the clearing line over central
KS shifting east and projects to reach the MO/KS border around 12z.
These clouds will then be replaced by broken VFR ceilings for most of
Tuesday. Should start to see scattered convection form or move into
west central MO and east central KS by late Tuesday evening.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...PMM
Aviation...MJ
AREA FORECAST DISCUSSION
NWS BILLINGS MT
1128 AM MDT TUE APR 19 2016
.UPDATE...
QUICK UPDATE THIS MORNING PRIMARILY TO CANCEL WINTER WEATHER
ADVISORIES IN BIG HORN COUNTY MONTANA AND SHERIDAN COUNTY
WYOMING...INCLUDING THE BIGHORN MOUNTAINS. THE THREAT OF
SIGNIFICANT SNOW ACCUMULATION HAS DIMINISHED GREATLY...WITH ONLY
RAIN SHOWERS EXPECTED OVER LOWER ELEVATIONS AND FOOTHILLS...AND
REDUCED SNOW ACCUMULATIONS IN THE HIGH TERRAIN.
HAVE ALSO PARED BACK POPS SIGNIFICANTLY ACROSS THE REGION BASED
ON HRRR GUIDANCE AND SATELLITE TRENDS OF MOISTURE TRANSFER...AS
WELL AS CURRENT OBS AROUND THE REGION. KEPT SLIGHT CHANCE POPS
ACROSS THE EAST THIS MORNING AND EARLY AFTERNOON...WITH CLEARING
FROM NORTH TO SOUTH THROUGH THE EVENING.
FINALLY EXTENDED THE MENTION OF PATCHY FOG ACROSS CENTRAL AND
EASTERN ZONES INTO THIS AFTERNOON...WITH GENERALLY LOW CIGS ACROSS
THE REGION CONTINUING TO IMPACT HIGHER HILLS AS FOG. GILSTAD
&&
.SHORT TERM...VALID FOR TDY AND WED...
SHOWERS WERE ONGOING ACROSS MUCH OF THE CENTRAL AND SOUTHERN
PORTIONS OF THE FORECAST AREA. A BACK EDGE TO THE PRECIPITATION WAS
SEEN OVER THE WESTERN DAKOTAS IN ASSOCIATION WITH A DRY SLOT
WORKING ITS WAY THROUGH THE UPPER LEVEL LOW. THE BEST MOISTURE AND
ENERGY WILL CONTINUE TO WORK SOUTH AND WEST THROUGH THE FORECAST
AREA DURING THE EARLY MORNING HOURS. THE BEST LOCATIONS FOR
ADDITIONAL PRECIP WILL BE OVER PORTIONS OF SOUTHERN BIG
HORN...SHERIDAN AND STILLWATER COUNTIES WHERE THE BEST UPSLOPE
FORCING WILL SQUEEZE OUT THE LAST OF THE MOISTURE. THE LAST BIT OF
MID-LEVEL COLD AIR WILL MOVE THROUGH AND GRADUALLY WARM THIS
MORNING OVER THE BIG HORNS. WITH THIS IN MIND HAVE LEFT THE WINTER
WEATHER ADVISORY INTACT THROUGH NOON...WHERE ADDITIONAL SNOW
AMOUNTS OF 1 TO 3 INCHES ARE POSSIBLE ABOVE 5000 FEET. FOR THE
REST OF THE MORNING...SHOWERS WILL QUICKLY DIMINISH FROM NORTH TO
SOUTH. WARMER TEMPERATURES IN THE MID 50S ARE EXPECTED THIS
AFTERNOON. RAIN AND SHOW SHOULD COMPLETELY CLEAR THE FORECAST AREA
BY THIS EVENING.
THE UPPER LEVEL LOW CONTINUES ITS EASTWARD TREK TONIGHT. UPPER
LEVEL RIDGING AND CLEARING SKIES WILL MOVE INTO THE FORECAST AREA
TONIGHT. FOG COULD BE A CONCERN LATE TONIGHT AS AMPLE BOUNDARY
LAYER MOISTURE WILL BE AVAILABLE AND WINDS WILL ALSO BE
RELATIVELY LIGHT. WITH THIS IN MIND PUT PATCHY FOG FROM ROUNDUP
TO RED LODGE AND LOCATIONS EAST. ANY FOG THAT FORMS SHOULD
DISSIPATE BY THE LATE MORNING AS UPPER LEVEL SUBSIDENCE AND DRY
AIR IS ADVECTED IN. EXPECT AN EVEN WARMER DAY IN THE UPPER 60S.
MOSTLY CLEAR CONDITIONS CONTINUE INTO THURSDAY MORNING SO WILL PUT
ADDITIONAL CHANCES FOR FOG IN THE WEATHER GRIDS...THOUGH IT WILL
LIKELY BE MORE SPORADIC. DOBBS
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
HIGH PRESSURE WILL PREVAIL OVER THE REGION WEDNESDAY THROUGH
FRIDAY WITH A WARMING TREND AND GENERALLY DRY CONDITIONS. LOOK FOR
HIGHS AROUND 80 BY FRIDAY WITH SOME ISOLATED CONVECTION POSSIBLE
IN THE WEST...MAINLY OVER THE HIGH COUNTRY.
BEYOND FRIDAY...MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WITH
SOLVING A DEVELOPING SPLIT FLOW ALOFT INVOLVED WITH AN UPPER LOW
DROPPING TO THE CALIFORNIA COAST. THE ECMWF BRINGS THE UPPER LOW
NORTH RIGHT OVER OUR REGION BY SUNDAY. THIS SOLUTION WOULD BE
MUCH WETTER AND DRASTICALLY COOLER THAN THE GFS SOLUTION WHICH
KEEPS THE UPPER DOWN IN THE DESERT BUT HAS A PROGRESSIVE TROUGH IN
THE NORTHERN STREAM MOVING WEST ACROSS THE ROCKIES. ENSEMBLES SHOW
A WIDE SPREAD ACROSS THE BOARD FOR EACH MODEL. RMOP /RELATIVE
MEASURE OF PREDICTABILLITY/ NUMBERS AREA QUITE LOW OVER OUR REGION
FOR THE WEEKEND. SO WILL STICK TO A BLEND TO REDUCE RISK OF BIG
BUST. BT
&&
.AVIATION...
VFR CONDITIONS EXPECTED TO PREVAIL MOST LOCATIONS THROUGH MIDNIGHT
TONIGHT...WITH THE ONLY EXCEPTION BEING IN THE VICINITY OF THE
MOUNTAINS WHERE SOME MOUNTAIN OBSCURATION CAN BE EXPECTED IN
ISOLATED MVFR CONDITIONS. AFTER MIDNIGHT EXPECT AREAS OF FOG TO
DEVELOP IN AN AREA EAST OF A SHERIDAN WYOMING TO BILLINGS LINE
WHICH IS EXPECTED TO CREATE MVFR CONDITIONS WITH SOME ISOLATED
IFR/LIFR UNTIL AFTER SUNRISE ON WEDNESDAY MORNING. ANTICIPATE FOG
TO BURN OFF BY MID-MORNING WEDNESDAY WITH FULL SUNSHINE. MEIER
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 055 039/071 042/078 048/082 049/072 047/062 041/056
6/W 10/U 00/U 00/U 02/T 43/W 33/W
LVM 062 037/072 039/077 042/081 042/071 040/061 037/055
2/W 10/U 01/U 00/U 13/T 44/W 44/W
HDN 053 035/071 036/079 040/082 042/074 042/066 038/057
4/W 20/U 00/U 00/U 02/T 33/W 32/W
MLS 054 038/068 039/077 044/081 045/071 045/065 040/056
2/W 10/U 00/U 00/U 01/B 34/W 33/W
4BQ 047 035/067 035/075 042/081 044/073 044/067 040/057
2/W 11/B 00/U 00/U 01/B 34/W 33/W
BHK 050 034/067 036/074 042/077 041/065 041/060 038/054
2/W 11/B 00/U 00/U 01/B 34/W 33/W
SHR 049 031/064 033/074 037/079 040/073 041/064 037/057
4/W 21/U 00/U 00/U 02/T 33/W 33/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
1126 AM MDT TUE APR 19 2016
.UPDATE...
QUICK UPDATE THIS MORNING PRIMARILY TO CANCEL WINTER WEATHER
ADVISORIES IN BIG HORN COUNTY MONTANA AND SHERIDAN COUNTY
WYOMING...INCLUDING THE BIGHORN MOUNTAINS. THE THREAT OF
SIGNIFICANT SNOW ACCUMULATION HAS DIMINISHED GREATLY...WITH ONLY
RAIN SHOWERS EXPECTED OVER LOWER ELEVATIONS AND FOOTHILLS...AND
REDUCED SNOW ACCUMULATIONS IN THE HIGH TERRAIN.
HAVE ALSO PARED BACK POPS SIGNIFICANTLY ACROSS THE REGION BASED
ON HRRR GUIDANCE AND SATELLITE TRENDS OF MOISTURE TRANSFER...AS
WELL AS CURRENT OBS AROUND THE REGION. KEPT SLIGHT CHANCE POPS
ACROSS THE EAST THIS MORNING AND EARLY AFTERNOON...WITH CLEARING
FROM NORTH TO SOUTH THROUGH THE EVENING.
FINALLY EXTENDED THE MENTION OF PATCHY FOG ACROSS CENTRAL AND
EASTERN ZONES INTO THIS AFTERNOON...WITH GENERALLY LOW CIGS ACROSS
THE REGION CONTINUING TO IMPACT HIGHER HILLS AS FOG. GILSTAD
&&
.SHORT TERM...VALID FOR TDY AND WED...
SHOWERS WERE ONGOING ACROSS MUCH OF THE CENTRAL AND SOUTHERN
PORTIONS OF THE FORECAST AREA. A BACK EDGE TO THE PRECIPITATION WAS
SEEN OVER THE WESTERN DAKOTAS IN ASSOCIATION WITH A DRY SLOT
WORKING ITS WAY THROUGH THE UPPER LEVEL LOW. THE BEST MOISTURE AND
ENERGY WILL CONTINUE TO WORK SOUTH AND WEST THROUGH THE FORECAST
AREA DURING THE EARLY MORNING HOURS. THE BEST LOCATIONS FOR
ADDITIONAL PRECIP WILL BE OVER PORTIONS OF SOUTHERN BIG
HORN...SHERIDAN AND STILLWATER COUNTIES WHERE THE BEST UPSLOPE
FORCING WILL SQUEEZE OUT THE LAST OF THE MOISTURE. THE LAST BIT OF
MID-LEVEL COLD AIR WILL MOVE THROUGH AND GRADUALLY WARM THIS
MORNING OVER THE BIG HORNS. WITH THIS IN MIND HAVE LEFT THE WINTER
WEATHER ADVISORY INTACT THROUGH NOON...WHERE ADDITIONAL SNOW
AMOUNTS OF 1 TO 3 INCHES ARE POSSIBLE ABOVE 5000 FEET. FOR THE
REST OF THE MORNING...SHOWERS WILL QUICKLY DIMINISH FROM NORTH TO
SOUTH. WARMER TEMPERATURES IN THE MID 50S ARE EXPECTED THIS
AFTERNOON. RAIN AND SHOW SHOULD COMPLETELY CLEAR THE FORECAST AREA
BY THIS EVENING.
THE UPPER LEVEL LOW CONTINUES ITS EASTWARD TREK TONIGHT. UPPER
LEVEL RIDGING AND CLEARING SKIES WILL MOVE INTO THE FORECAST AREA
TONIGHT. FOG COULD BE A CONCERN LATE TONIGHT AS AMPLE BOUNDARY
LAYER MOISTURE WILL BE AVAILABLE AND WINDS WILL ALSO BE
RELATIVELY LIGHT. WITH THIS IN MIND PUT PATCHY FOG FROM ROUNDUP
TO RED LODGE AND LOCATIONS EAST. ANY FOG THAT FORMS SHOULD
DISSIPATE BY THE LATE MORNING AS UPPER LEVEL SUBSIDENCE AND DRY
AIR IS ADVECTED IN. EXPECT AN EVEN WARMER DAY IN THE UPPER 60S.
MOSTLY CLEAR CONDITIONS CONTINUE INTO THURSDAY MORNING SO WILL PUT
ADDITIONAL CHANCES FOR FOG IN THE WEATHER GRIDS...THOUGH IT WILL
LIKELY BE MORE SPORADIC. DOBBS
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
HIGH PRESSURE WILL PREVAIL OVER THE REGION WEDNESDAY THROUGH
FRIDAY WITH A WARMING TREND AND GENERALLY DRY CONDITIONS. LOOK FOR
HIGHS AROUND 80 BY FRIDAY WITH SOME ISOLATED CONVECTION POSSIBLE
IN THE WEST...MAINLY OVER THE HIGH COUNTRY.
BEYOND FRIDAY...MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WITH
SOLVING A DEVELOPING SPLIT FLOW ALOFT INVOLVED WITH AN UPPER LOW
DROPPING TO THE CALIFORNIA COAST. THE ECMWF BRINGS THE UPPER LOW
NORTH RIGHT OVER OUR REGION BY SUNDAY. THIS SOLUTION WOULD BE
MUCH WETTER AND DRASTICALLY COOLER THAN THE GFS SOLUTION WHICH
KEEPS THE UPPER DOWN IN THE DESERT BUT HAS A PROGRESSIVE TROUGH IN
THE NORTHERN STREAM MOVING WEST ACROSS THE ROCKIES. ENSEMBLES SHOW
A WIDE SPREAD ACROSS THE BOARD FOR EACH MODEL. RMOP /RELATIVE
MEASURE OF PREDICTABILLITY/ NUMBERS AREA QUITE LOW OVER OUR REGION
FOR THE WEEKEND. SO WILL STICK TO A BLEND TO REDUCE RISK OF BIG
BUST. BT
&&
.AVIATION...
WIDESPREAD RAIN AND MIXED RAIN AND SNOW WILL CONTINUE ACROSS THE
FORECAST AREA THROUGH 18Z BEFORE SLOWLY DIMINISHING IN THE
AFTERNOON. MVFR TO IFR CONDITIONS OR LOWER ARE LIKELY EAST AND
SOUTH OF KBIL INCLUDING KSHR AND KMLS...AND ALONG THE FOOTHILL
LOCATIONS AROUND RED LODGE. VFR TO MVFR CONDITIONS ARE EXPECTED
W/NW OF KBIL. MOUNTAINS WILL BE OBSCURED. LOOK FOR SURFACE
VISIBILITIES TO BECOME PRIMARILY VFR IN THE AFTERNOON AND
CEILINGS TO BECOME PRIMARILY VFR TO MVFR BY 00Z WEDNESDAY. BT
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 055 039/071 042/078 048/082 049/072 047/062 041/056
6/W 10/U 00/U 00/U 02/T 43/W 33/W
LVM 062 037/072 039/077 042/081 042/071 040/061 037/055
2/W 10/U 01/U 00/U 13/T 44/W 44/W
HDN 053 035/071 036/079 040/082 042/074 042/066 038/057
4/W 20/U 00/U 00/U 02/T 33/W 32/W
MLS 054 038/068 039/077 044/081 045/071 045/065 040/056
2/W 10/U 00/U 00/U 01/B 34/W 33/W
4BQ 047 035/067 035/075 042/081 044/073 044/067 040/057
2/W 11/B 00/U 00/U 01/B 34/W 33/W
BHK 050 034/067 036/074 042/077 041/065 041/060 038/054
2/W 11/B 00/U 00/U 01/B 34/W 33/W
SHR 049 031/064 033/074 037/079 040/073 041/064 037/057
4/W 21/U 00/U 00/U 02/T 33/W 33/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 PM CDT WED APR 20 2016
.SYNOPSIS...
ISSUED AT 405 PM CDT WED APR 20 2016
H5 ANALYSIS THIS MORNING HAD A CLOSED LOW OVER NORTH PLATTE WITH
RIDGING OFF TO THE WEST OVER THE INTERMOUNTAIN WEST INTO THE
PANHANDLE OF IDAHO. EAST OF THE LOW...A LOW AMPLITUDE RIDGE OF
HIGH PRESSURE EXTENDS FROM THE FLORIDA PANHANDLE NORTH TO THE
OHIO VALLEY. HT FALLS THIS MORNING WERE MOST PRONOUNCED ACROSS
EASTERN KANSAS AND EASTERN NEBRASKA...WITH 70 METER FALLS NOTED AT
OMAHA AND 100 METER FALLS NOTED AT TOPEKA. CURRENT SATELLITE
IMAGERY HAS THE LOW NEAR LEXINGTON NEBRASKA WITH A SECONDARY
CIRCULATION NOTED AROUND OMAHA. SHOWERS HAVE CONTINUED TO ROTATE
AROUND THE NORTHERN AND WESTERN PERIPHERY OF THE LOW TODAY AND
HAVE MADE IT AS FAR WEST AS A MERRIMAN TO OGALLALA LINE. OVER THE
PAST COUPLE OF HOURS...SOME CONVECTIVE SHOWERS HAVE DEVELOPED OVER
SERN LINCOLN AND FRONTIER COUNTIES. ELSEWHERE...A MORE PERSISTENT
SHIELD OF RAIN WAS OCCURRING ACROSS THE NEBRASKA SANDHILLS.
HOURLY RAINFALL RATES WERE LIGHT...AT OR UNDER 3 HUNDREDTHS OF AN
INCH. TEMPERATURES AS OF 3 PM CDT RANGED FROM 51 TO 59 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 PM CDT WED APR 20 2016
THIS EVENING AND TONIGHT...EXPANDED HIGH CHC POPS WEST TO HWY 83
TO ACCOUNT FOR SCATTERED SHOWERS ROTATING AROUND THE LOW. ALSO
EXPANDED ISO THUNDER MENTION FOR SOUTHERN HALF OF THE FORECAST
AREA. FORECAST SOUNDINGS SHOW STEEP LOW LEVEL LAPSE RATES AND
PERIODS OF SIGNIFICANT LIFT. RAP ANALYSIS ALSO SHOWS MARGINAL
CAPE...GENERALLY 500 J/KG OR LESS...LIFTED INDEX AS LOW AS -1...
AND MID LEVEL LAPSE RATES NEAR 7C/KM. GIVEN DEEP COLD AIR
ALOFT...SMALL HAIL IS POSSIBLE WITH ANY STORM. HRRR AND RAP
INDICATE MOST OF THE SHOWER/STORM ACTIVITY OUTSIDE NORTH CENTRAL
NEBRASKA WILL BE DIURNALLY DRIVEN. SLOWLY PULL POPS FOR
BOYD...HOLT...WHEELER COUNTIES TONIGHT DUE TO THE PROXIMITY OF AN
AREA OF STEADY RAIN OVER NORTHEAST NEBRASKA. MADE LITTLE CHANGE TO
MIN TEMPS AS PREVIOUS FORECAST LOWS ARE SIMILAR TO 12Z MOS
GUIDANCE SUITE...COOLER PANHANDLE AND WEST FOR CLEARING SKY AND
LIGHT WINDS AND MILD NORTH CENTRAL FOR SUSTAINED CLOUDINESS.
DESPITE RECENT RAINFALL AND LIGHTENING WINDS OVERNIGHT...RISK OF
FOG IS LOW. SLIGHTLY DRIER AIR MOVES IN AS SHOWN BY FALLING MIXING
RATIOS...AND AS SURFACE WINDS TURN WESTERLY/NORTHWESTER...ITS NOT
AS FAVORABLE FOR FOG FORMATION.
THURSDAY...H5 LOW SCOOTS EAST INTO IOWA AND THE H3 JET MAX CENTERS
OVER THE MISSOURI RIVER. TRENDED MAX TEMPS TOWARD THE MAV...WHICH
RESULTED IN AN INCREASE OF A DEGREE OR SO AREAWIDE. NAM SOUNDINGS
INDICATE DRY AIR ALOFT...WEAK TO NON EXISTENT LIFT IN THE LOWER
LEVELS...AND A MIXED LAYER APPROACH 700HPA. MID LEVEL FGEN FORCING
ALSO WEAKENS AS THE LOW MOVES EAST OF THE AREA. WITH MAINLY FAIR
CONDITIONS AND UNINHIBITED MIXING...BREEZY NORTH WINDS ARE LIKELY
AND H85 TEMPS AROUND 10C SHOULD TRANSLATE TO HIGHS NEAR 70F.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 405 PM CDT WED APR 20 2016
MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE MID RANGE...A
BENIGN WEATHER PATTERN IS EXPECTED IN THE MID RANGE WITH
TEMPERATURES BEING THE MAIN FORECASTING CHALLENGE. THE CLOSED LOW
WILL TRACK INTO THE OHIO VALLEY THURSDAY NIGHT INTO FRIDAY...WHILE
RIDGING ALOFT BUILDS EAST FROM THE CENTRAL ROCKIES INTO THE
CENTRAL PLAINS. TEMPERATURES FRIDAY WILL REACH THE LOWER TO MIDDLE
70S...FOLLOWED BY MID 70S TO AROUND 80 FOR SATURDAY. THE LATEST
NAM SOLN WAS BEGINNING TO INDICATE A FAVORABLE ENVIRONMENT FOR
THUNDERSTORMS SATURDAY AFTERNOON IN THE WEST WITH VERY FAVORABLE
SURFACE BASED INSTABILITY AND A DECENT AMOUNT OF SD CAPE.
HOWEVER...SHEAR LOOKS WEAK ATTM. THE GFS AND ECMWF SOLNS HOLD OFF
ON CONVECTION UNTIL SAT EVENING AND HAVE OPTED TO GO THIS ROUTE
AND LEAVE SAT AFTERNOON DRY FOR NOW. BETTER CHANCES FOR
PRECIPITATION WILL ARRIVE IN THE WEST SATURDAY EVENING AS A LEAD
SHORTWAVE CROSSES THE PANHANDLE.
LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...BEGINNING SATURDAY
NIGHT...CHANCES FOR PCPN WILL INCREASE IN THE WEST AS A LEAD
SHORTWAVE CROSSES THE PANHANDLE. THIS WILL BE FOLLOWED BY A CLOSED
LOW WHICH TRACKS ACROSS SRN SD SUNDAY INTO SUNDAY NIGHT. WRAP
AROUND PCPN FROM THE SYSTEM WILL IMPACT THE NORTHERN CWA ON
SUNDAY AND SUNDAY NIGHT. FURTHER SOUTH...COOLER AND WINDY CONDS
ARE EXPECTED SUNDAY...WITH NOT MUCH IN THE WAY OF PCPN EXPECTED.
BETTER CHANCES FOR PRECIPITATION WILL ARRIVE MONDAY NIGHT INTO
WEDNESDAY AS A SECOND UPPER LOW LEVEL LOW TRACKS FROM THE CENTRAL
ROCKIES ONTO THE CENTRAL PLAINS. TEMPERATURES WILL BE MUCH COOLER
AS WELL WITH HIGHS IN THE 50S BY MIDWEEK NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 623 PM CDT WED APR 20 2016
THE RAIN AND LOCAL MVFR CIGS SHOULD EXIT THE FCST AREA AOA 06Z-07Z THIS
EVENING AS SHOWN BY THE RAP AND HRRR MODELS. THEREAFTER MIDLEVEL
DRYING AND NORTH WINDS SHOULD PRODUCE VFR CONDITIONS ALL AREAS
THROUGH THURSDAY AFTN. THE MODELS SUGGEST ISOLD SHRA/MVFR CIGS
EAST OF HWY 183 THURSDAY AFTN.
&&
.HYDROLOGY...
ISSUED AT 405 PM CDT WED APR 20 2016
RISES EXPECTED TO CONTINUE ON THE SOUTH PLATTE RIVER FOR THE NEXT
SEVERAL DAYS DUE TO RECENT PRECIPITATION OVER WESTERN NEBRASKA
AND COLORADO. USGS STREAM GAUGE AT ATWOOD CO HAS SHOWN A LEVELING
OFF WHILE JULESBURG STILL SHOWS A STEADY RISE. IN COORDINATION
WITH THE MBRFC...A FORECAST SHOWS A CREST AROUND 7 FEET LATE
FRIDAY AT ROSCOE...WHICH PUTS IT AT ACTION STAGE. NO FLOODING IS
EXPECTED AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...CDC
HYDROLOGY...BUTTLER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
120 AM CDT TUE APR 19 2016
.UPDATE...
ISSUED AT 120 AM CDT TUE APR 19 2016
MAIN UPDATE FOR THE EARLY MORNING FORECAST ISSUANCE WAS TO TREND
POPS BACK ACROSS THE SOUTH WHERE RADAR IS VOID OF ECHOS. ALSO
TRENDED THE DISSIPATION OF RAIN A BIT FASTER AS LATEST TRENDS AND
HIGH RES GUIDANCE INDICATE. FORCING WILL BE ON THE DECREASE
THROUGH THE MORNING HOURS NOW AS THE EMBEDDED S/WV WHICH TRIGGERED
THE LARGE BAND OF PRECIPITATION ROTATES SOUTHWEST OUT OF THE
REGION...WITH OMEGA RAPIDLY DECREASING IN ITS WAKE.
UPDATE ISSUED AT 928 PM CDT MON APR 18 2016
RECENT RAP SIMULATIONS /ESPECIALLY ITS 01 UTC RUN/ AND THE 00 UTC
NAM ARE PARTICULARLY IN SYNC WITH OBSERVED RADAR TRENDS...SO WE
RELIED ON THEM TO REFINE HOURLY POPS THROUGH 15 UTC. THIS ONCE
AGAIN MEANT DELAYING THE NORTHWARD SPREAD OF RAINFALL AND HENCE A
REDUCTION IN OVERALL POPS ALONG THE HIGHWAY 2 CORRIDOR SUCH THAT
THEY MAXIMIZE ONLY AROUND 50 PERCENT AT MINOT TUESDAY MORNING.
THE MAIN SHIELD OF RAIN IS WELL-ESTABLISHED AND INTENSIFYING
ACROSS SOUTHERN ND AT 02 UTC...AND PER RAP AND NAM OMEGA FIELDS
SHOULD BE AT ITS PEAK THROUGH ABOUT 09 UTC...AFTER WHICH BOTH MID-
LEVEL FRONTOGENESIS AND THETA-E ADVECTION /AND FORCING ON
ISENTROPIC SURFACES/ QUICKLY WANES.
UPDATE ISSUED AT 610 PM CDT MON APR 18 2016
RAIN IS FILLING IN OVER SOUTHWEST AND SOUTH CENTRAL ND...AND THE
BETTER-FORCED BATCH OF MORE WIDESPREAD RAIN IN NORTHERN SD IS ON
TRACK TO EASE INTO THE AREA THIS EVENING TOO. THE MAIN CHANGE WE
MADE WITH THIS UPDATE WAS TO SLOW THE NORTHWARD ADVANCE OF HIGHER
POPS OVER NORTHWEST AND NORTH CENTRAL ND AS RADAR IMAGERY REVEALS
A FASTER EAST TO WEST TRANSLATION THAN A NORTHWARD MOVEMENT. THUS
POPS FROM WILLISTON TO MINOT AND RUGBY WERE RATHER SIGNIFICANTLY
LOWERED THROUGH 06 UTC. OTHERWISE...WE ARE MONITORING ADVECTION/
UPSLOPE-AIDED FOG ALONG THE COTEAU REGION OF NORTHWEST AND CENTRAL
ND...BUT ARE HANDLING IT WITH A SPECIAL WEATHER STATEMENT AND WEB
GRAPHIC VICE AN ADVISORY UNTIL OR UNLESS IT BECOMES APPARENT THAT
IT WILL BECOME MORE WIDESPREAD.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 235 PM CDT MON APR 18 2016
CURRENT SURFACE ANALYSIS PLACES LOW OVER SOUTHEASTERN SOUTH DAKOTA
WITH HIGH OVER SOUTHERN SASKATCHEWAN/MANITOBA/ONTARIO. UPPER
LEVEL ANALYSIS PLACES BROAD LOW CENTERED OVER THE CENTRAL ROCKIES
WITH BLOCKING RIDGE STRETCHING FROM THE GULF UP INTO THE OHIO
RIVER VALLEY. MOISTURE CONTINUES TO STREAM INTO THE AREA AHEAD OF
THE LOW WITH SOME SHOWERS CURRENTLY OVER THE AREA.
FOR THE REST OF THIS AFTERNOON INTO THIS EVENING...RAIN COVERAGE
WILL BE ON THE INCREASE PRIMARILY OVER SOUTHERN LOCATIONS AS NEXT
WAVE PRODUCING BROAD AREA OF PRECIPITATION OVER SOUTH DAKOTA
GRADUALLY LIFTS INTO THE AREA LATE THIS AFTERNOON INTO THIS
EVENING. WARM AIR ADVECTION ALOFT SUGGESTS THAT PRECIPITATION
SHOULD REMAIN AS RAIN THROUGHOUT THE AREA WHICH IS ALSO SHOW ON
FORECAST SOUNDINGS. ONLY PLACE THAT WE MAY NEED TO KEEP AN EYE ON
OVERNIGHT WOULD BE OVER FAR SOUTHWEST NORTH DAKOTA IN THE HIGHER
ELEVATIONS...THOUGH IF ANY SNOW WERE TO DEVELOP IT WOULD BE SHORT
LIVED. THE NEXT CONCERN WOULD BE FOG WITH PLENTY OF MOISTURE IN
PLACE AND VARIOUS LOCATIONS AROUND THE AREA ALREADY REPORTING
REDUCED VISIBILITIES. MORE OR LESS WENT WITH A BROAD-BRUSH
APPROACH WITH THE GREATEST COVERAGE NORTHEAST OF THE
COTEAU...SPREADING SOUTHWEST LATE TONIGHT.
ON TUESDAY...FOG MAY LINGER OVER THE AREA THROUGH THE MORNING
HOURS BEFORE DIMINISHING. OTHERWISE...EXPECT A GRADUAL DISSIPATION
OF PRECIPITATION AS UPPER LOW STARTS A SLOW MOVE TOWARDS THE
CENTRAL PLAINS AS RIDGE TO THE EAST BREAKS DOWN. THIS WILL ALLOW
MILDER TEMPERATURES THROUGH THE AREA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 235 PM CDT MON APR 18 2016
UPPER LOW GRADUALLY WORKS FROM THE CENTRAL PLAINS INTO THE MIDWEST
TUESDAY NIGHT INTO WEDNESDAY WITH RIDGE BUILDING INTO THE AREA
BRINGING DRIER CONDITIONS AND MILD TEMPERATURES. RIDGE WILL BRING
MAINLY DRY CONDITIONS GOING INTO THE WEEKEND. MODELS SUGGEST AN
UNSETTLED PATTERN DEVELOPING ON SUNDAY AND CONTINUING INTO NEXT
WEEK THOUGH ARE HAVING PROBLEMS WITH THE PLACEMENT OF SOME KEY
FEATURES. THEREFORE...WILL KEEP CHANCES FOR PRECIPITATION IN THE
FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 120 AM CDT TUE APR 19 2016
WIDESPREAD IFR AND SOME LIFR CONDITIONS WILL CONTINUE TONIGHT
INTO TUESDAY MORNING ACROSS WESTERN AND CENTRAL ND AS SLOW-MOVING
LOW PRESSURE MOVES EAST ACROSS THE CENTRAL PLAINS. RAIN WILL BE
MOST PERSISTENT AND THE MOST INTENSE OVER SOUTHWEST AND SOUTH
CENTRAL ND...BUT AT LEAST A CHANCE OF RAIN EXISTS FOR ALMOST ALL
OF WESTERN AND CENTRAL ND AT SOME POINT TONIGHT AND TUESDAY
MORNING. CONDITIONS IMPROVE TUESDAY AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JJS
LONG TERM...JJS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS Tulsa OK
258 PM CDT TUE APR 19 2016
.DISCUSSION...
Persistent areas of light rain have plagued northeast Oklahoma much
of Today as strong isentropic lift and a mid-level shortwave easing
across the area have combined forces to wring the plentiful moisture
out of the air. The HRRR has this activity breaking down over the next
few hours in advance of the next round of showers and thunderstorms.
The next round of showers and thunderstorms is expected to move into
eastern Oklahoma later this evening as the upper level low that has been
stuck over the Rockies finally begins to move off to the east. This activity
is expected to be east and south of the forecast area by sunrise on Wednesday.
Additional showers and thunderstorms will be possible Wednesday night into
Thursday as a secondary upper level low scoots across the area. The best
chances of showers and thunderstorms will be south of Interstate 40.The chances
of showers and thunderstorms end Thursday evening as a storm system finally
moves east of the area.
High pressure aloft and at the surface prevails through much of the weekend
providing dry conditions and warmer temperatures. Chances of showers and
thunderstorms return early next week with the approach of the next storm
system.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 54 72 52 74 / 90 10 20 20
FSM 60 75 56 76 / 60 60 20 20
MLC 58 74 53 73 / 80 30 30 30
BVO 51 72 48 75 / 90 10 20 20
FYV 54 71 49 72 / 60 50 20 20
BYV 54 72 51 74 / 40 50 20 20
MKO 57 74 52 74 / 80 30 20 20
MIO 55 72 51 74 / 80 30 20 20
F10 57 72 53 73 / 80 20 20 20
HHW 61 75 57 73 / 70 50 30 40
&&
.TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...18
LONG TERM....10
AREA FORECAST DISCUSSION
NWS Tulsa OK
1132 PM CDT MON APR 18 2016
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Ceilings and visibilities have not diminished as quickly as
earlier expected so the main change to the TAFs has been to push
back the IFR/MVFR visibilities and lower ceilings to 08-09Z. Low
level moisture looks to diminish some near the NE OK terminals
mid to late afternoon tomorrow with VFR conditions now expected.
Daytime showers looking like they will be more spotty so will
transition the earlier PROB30 mentions of showers to VCSH at all
terminals. Additional showers looking likely late tomorrow evening
and especially after the valid TAF period so will include PROB30
mention at the E OK terminals at the very end of the TAF period.
&&
.PREV DISCUSSION... /ISSUED 924 PM CDT MON APR 18 2016/
DISCUSSION...
Narrow band of showers continues across parts
of eastern OK...along weak front/inverted surface
trof where modest dewpoint pooling was occurring.
This activity has been slowly diminishing this
evening...and HRRR suggests this trend will continue.
Could see an slight uptick in coverage across southeast
OK and western AR later tonight as low-level strengthens
some across eastern TX.
Have maintained highest pops across our eastern sections
the rest of the night...and will remove mention of
thunder.
&&
.TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...22
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1001 PM CDT WED APR 20 2016
.DISCUSSION...ONGOING SEVERE THUNDERSTORMS AND HEAVY RAINFALL
CONTINUES OVER ZAPATA COUNTY LATE THIS EVENING. THE CONVECTION IS
EXPECTED TO WEAKEN OVER THE COUPLE OF HOURS AS THE ATMOSPHERE
BECOMES MORE STABLE. MADE A QUICK UPDATE TO INCREASE POPS ACROSS
ZAPATA COUNTY AND LOWER POPS ACROSS THE EASTERN PORTIONS OF DEEP
SOUTH TEXAS. THE REST OF THE FORECAST LOOKS GOOD AND NO OTHER
CHANGES NEEDED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 708 PM CDT WED APR 20 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...SATELLITE AND RADAR IMAGES INDICATE SOME ONGOING
CONVECTION WITH MID TO HIGH LEVEL CLOUDS OVER THE MOUNTAINS OF
NORTHEAST MEXICO THIS EVENING. WITH SURFACE INSTABILITY
RELATIVELY HIGH ACROSS THE PORTIONS OF DEEP SOUTH TEXAS AND WEST
TO EAST FLOW ALOFT...THERE IS A SMALL CHANCE THAT SOME STORMS
COULD MOVE INTO THE WESTERN PORTIONS OF THE CWA LATER THIS
EVENING. AN ISOLATED STORM COULD IMPACT MFE THROUGH LATE THIS
EVENING...SO WILL CONTINUE TO MENTION VCTS FOR MFE THROUGH 04Z.
OTHERWISE...MID TO HIGH LEVEL CLOUD COVER WILL INCREASE ACROSS THE
RIO GRANDE VALLEY THROUGH THIS EVENING DUE TO DEBRIS CLOUDS FROM
THE EARLIER STORMS OVER NORTHERN MEXICO. LOW CLOUDS EXPECTED TO
DEVELOP LATER THIS EVENING RESULTING IN MVFR TO POSSIBLE IFR
CEILINGS OVERNIGHT. VFR CONDITIONS WILL RETURN LATE THURSDAY
MORNING INTO EARLY AFTERNOON.
PREV DISCUSSION... /ISSUED 311 PM CDT WED APR 20 2016/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...SATELLITE AND RADAR
IMAGES INDICATE CONVECTION CONTINUING TO DEVELOP ACROSS NORTHEAST
MEXICO THIS AFTERNOON AND BOTH THE NAM AND HRRR CONTINUE TO
INDICATE CONVECTION DEVELOPING ACROSS EXTREME WESTERN PORTIONS OF
THE CWA LATE THIS AFTERNOON INTO THIS EVENING. WITH THE SURFACE
INSTABILITY REMAINING HIGH ACROSS THE RIO GRANDE VALLEY AND
NORTHERN RANCHLANDS...CANNOT RULE OUT THE POTENTIAL FOR ISOLATED
SEVERE THUNDERSTORMS ACROSS PORTIONS OF ZAPATA...JIM HOGG...AND
STARR COUNTIES THIS EVENING. THE GREATEST THREAT FOR SEVERE
APPEARS TO BE HAIL AND DAMAGING WINDS. HEAVY RAINFALL CAN BE
EXPECTED WITH SOME OF THE STRONGER TO SEVERE STORMS. WILL GO WITH
THE HIGHEST POPS ACROSS THE WESTERN PORTIONS OF THE CWA WITH LOWER
POPS TOWARDS THE COAST THIS EVENING.
THE FORECAST FOR THURSDAY AND THURS NIGHT IS CHALLENGING WITH THE
WEST TO NORTHWEST FLOW ALOFT BUT THE NAM AND GFS HAVE A CONVECTIVE
BOUNDARY DEVELOPING ACROSS PORTIONS OF CENTRAL TX THURSDAY AND AS
THIS FEATURE MOVES SOUTHWARD IT WILL PROVIDE A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE CWA THURSDAY INTO
THURS NIGHT AS MOISTURE POOLS ALONG AND AHEAD OF A WEAK COLD FRONT
MOVES SOUTHWARD ACROSS SOUTH TX.
LONG TERM /FRIDAY THROUGH WEDNESDAY/...UPPER LEVEL RIDGE WILL
BEGINS TO BUILD ACROSS THE DESERT SOUTHWEST INTO S TEXAS FRIDAY
WITH A WEAK FRONT MOVING SOUTH. WEAK FRONT COMBINED WITH PERTURBATIONS
WITHIN THE FLOW WILL ENHANCE SHOWERS AND THUNDERSTORMS ACROSS THE
CWA. THE BOUNDARY WILL STALLED OVER DEEP SOUTH TEXAS WITH WINDS
REMAINING EASTERLY INTO SATURDAY. AN ABUNDANT SURGE OF MOISTURE
WILL MOVE INTO THE AREA CONTINUING THE DEVELOPMENT OF MORE SHOWERS
AND THUNDERSTORMS ACROSS THE WESTERN COUNTIES THIS WEEKEND. MODEL
GUIDANCE CONTINUE TO SHOW ABOVE 1.5 IN OF PRECIPITABLE WATER
THROUGH THE WEEKEND WHICH WILL FAVOR THE DEVELOPMENT WITH THIS
TROUGH AS IT MOVES EASTWARD. DRIER AIR MASS MOVES INTO THE AREA
MONDAY WITH LESS SIDE TROUGH DEVELOPING OVER SOUTH CENTRAL TEXAS.
THIS WILL LIMIT THE POTENTIAL FOR RAIN BUT A FEW ISOLATED SHOWERS
CAN`T BE RULED NEAR THE COAST WITH THE SEABREEZE. THE RIDGE WILL
BE IN CONTROL OF THE AREA MONDAY AND TUESDAY LIMITING THE
POTENTIAL FOR RAIN THROUGH MID WEEK. THE SOUTHERLY FLOW WILL
INCREASE TO MORE BREEZE CONDITIONS MONDAY AS THE NEXT UPPER TROUGH
STRENGTHENS OVER THE PAC NORTHWEST. MODELS ARE IN PRETTY GOOD
AGREEMENT WITH GFS BEEN SLIGHTLY MORE PROGRESSIVE WITH THE NEXT
LOW PRESSURE SYSTEM WHILE THE ECMWF IS A BIT SLOWER. EVEN WITH THE
SLIGHT DIFFERENCE STILL SHOW THE POTENTIAL FOR RAIN FOR THE
WEEKEND AND THE DRY AIR FILTERING IN BY EARLY NEXT WEEK. LEAN
TOWARDS A BLEND OF THE TWO MODELS FOR THIS PACKAGE.
MARINE...TONIGHT THROUGH THURSDAY NIGHT...SEAS WERE NEAR 4 FEET
WITH EAST TO SOUTHEAST WINDS NEAR 10 KNOTS AT BUOY020 EARLY THIS
AFTERNOON. LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS TONIGHT INTO THURSDAY WITH LOW PRESSURE ACROSS
NORTHEAST MEXICO AND A WEAK COLD FRONT DRAPED ACROSS NORTH TEXAS.
THE BOUNDARY WILL MOVE INTO SOUTH TX THURS NIGHT AND THIS WILL
CONTINUE TO PROVIDE A WEAK PRESSURE GRADIENT ACROSS THE LOWER TX
COAST.
FRIDAY THROUGH TUESDAY...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
FOR THE EARLY PORTION OF THE LONG TERM PERIOD AS ABUNDANT MOISTURE
IN THE REGION WILL ALLOW FOR CONVECTION TO CONTINUE. EXPECT A
MODERATE SOUTHEAST FLOW ACROSS THE GULF WITH SEAS BETWEEN 2 TO 4
FEET THROUGH THE WEEKEND. RIDGE BEGINS TO BUILD LOWERING SEAS EVEN
LESS THAN 2 FEET SAT AND SUN. AN INFLUX OF MOISTURE WILL SURGE
NORTH SAT NIGHT INTO SUN INCREASING THE CHANCE OF SHOWERS ONCE
AGAIN. SEAS WILL BEGIN TO INCREASE INTO MONDAY AS A STRONG SURFACE
LOW STRENGTHENS OVER THE CENTRAL PLAINS. SEAS WILL BEGIN TO BUILD
TO 3 TO 6 FEET WITH SCEC POSSIBLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 72 82 71 80 / 10 20 20 20
BROWNSVILLE 72 85 71 83 / 10 20 20 30
HARLINGEN 71 87 70 84 / 10 20 20 30
MCALLEN 72 90 71 87 / 10 30 20 30
RIO GRANDE CITY 71 92 70 88 / 30 20 30 30
SOUTH PADRE ISLAND 72 78 71 77 / 10 20 20 20
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM...63
LONG TERM/UPPER AIR...60
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
708 PM CDT WED APR 20 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...SATELLITE AND RADAR IMAGES INDICATE SOME ONGOING
CONVECTION WITH MID TO HIGH LEVEL CLOUDS OVER THE MOUNTAINS OF
NORTHEAST MEXICO THIS EVENING. WITH SURFACE INSTABILITY
RELATIVELY HIGH ACROSS THE PORTIONS OF DEEP SOUTH TEXAS AND WEST
TO EAST FLOW ALOFT...THERE IS A SMALL CHANCE THAT SOME STORMS
COULD MOVE INTO THE WESTERN PORTIONS OF THE CWA LATER THIS
EVENING. AN ISOLATED STORM COULD IMPACT MFE THROUGH LATE THIS
EVENING...SO WILL CONTINUE TO MENTION VCTS FOR MFE THROUGH 04Z.
OTHERWISE...MID TO HIGH LEVEL CLOUD COVER WILL INCREASE ACROSS THE
RIO GRANDE VALLEY THROUGH THIS EVENING DUE TO DEBRIS CLOUDS FROM
THE EARLIER STORMS OVER NORTHERN MEXICO. LOW CLOUDS EXPECTED TO
DEVELOP LATER THIS EVENING RESULTING IN MVFR TO POSSIBLE IFR
CEILINGS OVERNIGHT. VFR CONDITIONS WILL RETURN LATE THURSDAY
MORNING INTO EARLY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 311 PM CDT WED APR 20 2016/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...SATELLITE AND RADAR
IMAGES INDICATE CONVECTION CONTINUING TO DEVELOP ACROSS NORTHEAST
MEXICO THIS AFTERNOON AND BOTH THE NAM AND HRRR CONTINUE TO
INDICATE CONVECTION DEVELOPING ACROSS EXTREME WESTERN PORTIONS OF
THE CWA LATE THIS AFTERNOON INTO THIS EVENING. WITH THE SURFACE
INSTABILITY REMAINING HIGH ACROSS THE RIO GRANDE VALLEY AND
NORTHERN RANCHLANDS...CANNOT RULE OUT THE POTENTIAL FOR ISOLATED
SEVERE THUNDERSTORMS ACROSS PORTIONS OF ZAPATA...JIM HOGG...AND
STARR COUNTIES THIS EVENING. THE GREATEST THREAT FOR SEVERE
APPEARS TO BE HAIL AND DAMAGING WINDS. HEAVY RAINFALL CAN BE
EXPECTED WITH SOME OF THE STRONGER TO SEVERE STORMS. WILL GO WITH
THE HIGHEST POPS ACROSS THE WESTERN PORTIONS OF THE CWA WITH LOWER
POPS TOWARDS THE COAST THIS EVENING.
THE FORECAST FOR THURSDAY AND THURS NIGHT IS CHALLENGING WITH THE
WEST TO NORTHWEST FLOW ALOFT BUT THE NAM AND GFS HAVE A CONVECTIVE
BOUNDARY DEVELOPING ACROSS PORTIONS OF CENTRAL TX THURSDAY AND AS
THIS FEATURE MOVES SOUTHWARD IT WILL PROVIDE A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE CWA THURSDAY INTO
THURS NIGHT AS MOISTURE POOLS ALONG AND AHEAD OF A WEAK COLD FRONT
MOVES SOUTHWARD ACROSS SOUTH TX.
LONG TERM /FRIDAY THROUGH WEDNESDAY/...UPPER LEVEL RIDGE WILL
BEGINS TO BUILD ACROSS THE DESERT SOUTHWEST INTO S TEXAS FRIDAY
WITH A WEAK FRONT MOVING SOUTH. WEAK FRONT COMBINED WITH PERTURBATIONS
WITHIN THE FLOW WILL ENHANCE SHOWERS AND THUNDERSTORMS ACROSS THE
CWA. THE BOUNDARY WILL STALLED OVER DEEP SOUTH TEXAS WITH WINDS
REMAINING EASTERLY INTO SATURDAY. AN ABUNDANT SURGE OF MOISTURE
WILL MOVE INTO THE AREA CONTINUING THE DEVELOPMENT OF MORE SHOWERS
AND THUNDERSTORMS ACROSS THE WESTERN COUNTIES THIS WEEKEND. MODEL
GUIDANCE CONTINUE TO SHOW ABOVE 1.5 IN OF PRECIPITABLE WATER
THROUGH THE WEEKEND WHICH WILL FAVOR THE DEVELOPMENT WITH THIS
TROUGH AS IT MOVES EASTWARD. DRIER AIR MASS MOVES INTO THE AREA
MONDAY WITH LESS SIDE TROUGH DEVELOPING OVER SOUTH CENTRAL TEXAS.
THIS WILL LIMIT THE POTENTIAL FOR RAIN BUT A FEW ISOLATED SHOWERS
CAN`T BE RULED NEAR THE COAST WITH THE SEABREEZE. THE RIDGE WILL
BE IN CONTROL OF THE AREA MONDAY AND TUESDAY LIMITING THE
POTENTIAL FOR RAIN THROUGH MID WEEK. THE SOUTHERLY FLOW WILL
INCREASE TO MORE BREEZE CONDITIONS MONDAY AS THE NEXT UPPER TROUGH
STRENGTHENS OVER THE PAC NORTHWEST. MODELS ARE IN PRETTY GOOD
AGREEMENT WITH GFS BEEN SLIGHTLY MORE PROGRESSIVE WITH THE NEXT
LOW PRESSURE SYSTEM WHILE THE ECMWF IS A BIT SLOWER. EVEN WITH THE
SLIGHT DIFFERENCE STILL SHOW THE POTENTIAL FOR RAIN FOR THE
WEEKEND AND THE DRY AIR FILTERING IN BY EARLY NEXT WEEK. LEAN
TOWARDS A BLEND OF THE TWO MODELS FOR THIS PACKAGE.
MARINE...TONIGHT THROUGH THURSDAY NIGHT...SEAS WERE NEAR 4 FEET
WITH EAST TO SOUTHEAST WINDS NEAR 10 KNOTS AT BUOY020 EARLY THIS
AFTERNOON. LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS TONIGHT INTO THURSDAY WITH LOW PRESSURE ACROSS
NORTHEAST MEXICO AND A WEAK COLD FRONT DRAPED ACROSS NORTH TEXAS.
THE BOUNDARY WILL MOVE INTO SOUTH TX THURS NIGHT AND THIS WILL
CONTINUE TO PROVIDE A WEAK PRESSURE GRADIENT ACROSS THE LOWER TX
COAST.
FRIDAY THROUGH TUESDAY...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
FOR THE EARLY PORTION OF THE LONG TERM PERIOD AS ABUNDANT MOISTURE
IN THE REGION WILL ALLOW FOR CONVECTION TO CONTINUE. EXPECT A
MODERATE SOUTHEAST FLOW ACROSS THE GULF WITH SEAS BETWEEN 2 TO 4
FEET THROUGH THE WEEKEND. RIDGE BEGINS TO BUILD LOWERING SEAS EVEN
LESS THAN 2 FEET SAT AND SUN. AN INFLUX OF MOISTURE WILL SURGE
NORTH SAT NIGHT INTO SUN INCREASING THE CHANCE OF SHOWERS ONCE
AGAIN. SEAS WILL BEGIN TO INCREASE INTO MONDAY AS A STRONG SURFACE
LOW STRENGTHENS OVER THE CENTRAL PLAINS. SEAS WILL BEGIN TO BUILD
TO 3 TO 6 FEET WITH SCEC POSSIBLE.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
318 PM CDT TUE APR 19 2016
.SHORT TERM...
PRECIP CHANCES WILL CONTINUE TO BE THE FOCUS TONIGHT AND AGAIN
WEDNESDAY. ONGOING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
BEGINNING TO MARCH EWD ACROSS THE NRN HALF OF THE FCST AREA AT A
PRETTY GOOD CLIP. THE SOURCE REGION FOR CONVECTIVE REDEVELOPMENT
THAT HAD BEEN ANCHORED IN ERN NM IS SHIFTING TO THE WRN SOUTH
PLAINS. THIS ADJUSTEMENT OCCURRING IN RESPONSE TO THE MAIN UPPER
TROUGH OVER NRN NM SHOWING EWD MOVEMENT PER WATER VAPOR IMAGERY THE
LAST COUPLE HOURS. TROUGH AXIS SHOULD SHIFT TO THE EAST OF THE FCST
AREA AROUND 06Z WITH HIGH CHANCE TO LIKELY POPS ERN HALF OF THE FCST
AREA APPROPRIATE UNTIL THEN. COULD ALSO SEE A SHIFT SWD WITH THE
CONVECTION AS OUTFLOW INTERACTS WITH LOW LEVEL MOISTURE SRN SOUTH
AND ROLLING PLAINS PER HRRR OUTPUT.
FOCUS THEN SHIFTS TO PRECIP CHANCE WEDNESDAY. APPEARS A DECENTLY
DEFINED DRYLINE WILL SHIFT INTO THE WRN ZONES DURING THE AFTN. LOW
LEVEL MOISTURE TO REMAIN IN PLACE TO ITS EAST WITH SFC DEW POINT
TEMPS UPPER 40S-LOWER 50S. NOT MUCH UPPER SUPPORT EVIDENT WITH A
SHORT WAVE TROUGH PROGGED TO SEWD THROUGH THE MEAN FLOW FROM SRN
COLORADO TWD THE PANHANDLE. WEAKLY FORCED CONVECTIVE INITIATION
POSSIBLE LATE AFTN JUST EAST OF THE DRYLINE GENERALLY ALONG I-27.
ONLY OTHER ISSUE IS CHANCE FOR FOG AROUND SUNRISE. COOL...MOIST AIR
MASS WITH UPSLOPE EASTERLY LOW LEVEL FLOW POINT TO THE POSSIBILITY.
NO CONSENUS FROM GUIDANCE ATTM. WILL KEEP MENTION OUT FOR NOW AND
LET NEXT SHIFT REEVALUATE.
.LONG TERM...
A SECONDARY COLD FRONT WILL PUSH THROUGH TOMORROW NIGHT AS A SHORT
WAVE ROTATES AROUND THE BACKSIDE OF THE MUCH LARGER UPPER LEVEL LOW
ACROSS THE MIDWEST. WITH PLENTY OF MOISTURE IN PLACE AS WELL AS LIFT
FROM THE SHORTWAVE A COMPLEX OF SHOWERS AND THUNDERSTORMS WILL BE
HIGHLY POSSIBLE ACROSS THE EASTERN TX PANHANDLE AND ROLLING PLAINS.
WHILE SOME HEAVY RAIN WILL BE POSSIBLE AS PWATS WILL BE OVER 1 INCH
THE COMPLEX SHOULD MOVE QUICK ENOUGH TO HELP MITIGATE FLOODING
CONCERNS. WINDS WILL REMAIN OUT OF THE NORTHEAST INTO LATE THURSDAY
NIGHT WHICH WILL HELP KEEP TEMPS INTO THE LOW 70S. WINDS WILL TURN
BACK TO THE SOUTH/SOUTHEAST BY EARLY FRIDAY AFTERNOON AS A LEE TROF
DEVELOPS. THIS...IN ADDITION TO AN UPPER RIDGE MOVING OVER THE
REGION...WILL ALLOW TEMPS TO WARM BACK TO NEAR AVERAGE FRIDAY. TEMPS
WILL CONTINUE TO WARM TO SEVERAL DEGREES ABOVE AVERAGE BY SUNDAY AS
WINDS WILL CONTINUOUSLY STAY OUT OF THE SOUTH TO SOUTHWEST. THE LEE
TROF WILL PUSH SOUTHWARD STARTING LATE SUNDAY MORNING ALLOWING A
DRYLINE TO PUSH EASTWARD FROM NM. A SMALL CHANCE EXISTS FOR ISOLATED
THUNDERSTORMS ALONG THE DRYLINE...MOSTLY OVER THE ROLLING
PLAINS...SUNDAY BUT WILL BE DEPENDENT ON THE TIMING OF A PASSING
SHORTWAVE. WINDS WILL BE FAIRLY BREEZY...SPECIFICALLY ACROSS OUR
NORTHWESTERN COUNTIES...BEHIND THE DRYLINE AS THE MID TO LOWER
LEVELS DRY AND THERMAL PROFILES BECOME SUPER ADIABATIC. CONDITIONS
BEYOND LATE SUNDAY BECOME QUESTIONABLE AS MODELS BEGIN TO DIVERGE
WITH THE UPPER LEVEL PATTERN. THE ECMWF BRINGS AN UPPER LEVEL LOW
CLOSE TO THE REGION BY MONDAY AFTERNOON/EVENING WHICH WOULD ALLOW
WINDS TO KEEP BLOWING WHILE THE GFS TAKES A MORE PACIFIST ROLE BY
KEEPING FLOW MOSTLY ZONAL AND DELAYING THE APPROACH OF THE LOW UNTIL
EARLY WEDNESDAY. EITHER WAY THE FORECAST LOOKS TO REMAIN DRY.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07/51
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
304 PM CDT TUE APR 19 2016
.SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
AT 245PM...VISIBLE SATELLITE SHOWED CONVECTIVE INITIATION
BEGINNING OFF THE MEXICAN MOUNTAINS AND UP THROUGH THE BIG BEND
AREA. FARTHER EAST INTO OUR CWA...STRATUS WAS JUST BEGINNING TO
DETERIORATE WHICH HAS BEEN LIMITING THE CONVECTIVE POTENTIAL.
HOWEVER STILL WITH A FEW HOURS OF HEATING LEFT IN THE DAY...A
SLIGHT CHANCE OF STRONG TO SEVERE THUNDERSTORMS COULD BE POSSIBLE
FOR THE WESTERN PLATEAU COUNTIES...LIKE VAL VERDE. LOW LEVEL LAPSE
RATES ON THE PLATEAU ARE SUB 6 DEG/KM PER THE RAP HOWEVER AND WITH
SUPERCELL STORM MOTION VECTORS WEST OF THE RIO GRANDE PARALLEL TO
THE RIVER AND APPRECIABLE CONVECTION INHIBITION FARTHER
EAST...CONFIDENCE IS LOW ON STORMS IN OUR CWA THIS EVENING.
HOWEVER...SHOULD SOME CELLS MAKE IT INTO THE CWA...ENOUGH
INSTABILITY MAY BE GENERATED BY LATE THIS AFTERNOON TO WARRANT A
MARGINALLY SEVERE HAIL THREAT.
THIS CONVECTION FARTHER WEST AND NORTH IS BEING PRETTY WELL
HANDLED IN THE HI RESOLUTION MODELS THIS AFTERNOON AND THEY ARE
INDICATING CONGLOMERATING INTO A QUASI LINEAR SYSTEM OR BROKEN
LINE OF MULTI CELLS PUSHING SOUTHEAST INTO THE NORTHERN CWA BY
EARLY TOMORROW MORNING. MORE SPECIFICALLY THE 4AM-10AM TIME FRAME.
THE LINE SHOULD BE ABLE TO PASS THROUGH AT A DECENT
SPEED...ENOUGH TO TYPICALLY NOT BE MUCH OF A CONCERN FOR FLASH
FLOODING. IN FACT...PWATS AT 12Z ARE ONLY IN THE 1.4 INCH RANGE IN
THE AUSTIN AREA. SO IT LOOKS LIKE QPF WISE...THAT GENERALLY AROUND
AN INCH OR SO WILL RESULT FROM THE PASSAGE OF THIS LINE.
HOWEVER...WHILE ISOLATED...THERE MAY BE SOME SPOTS THAT GET 3
INCHES OR SO WHICH WOULD BE QUITE PROBLEMATIC FOR COUNTIES IN THE
EAST WHICH RECEIVED OVER 8 INCHES OF RAIN FROM YESTERDAY.
THEREFORE THE DECISION TO MAINTAIN A FFA EAST OF I35 WAS MADE FOR
THOSE HIGHLY VULNERABLE ANTECEDENT COUNTIES SPECIFICALLY...WHILE
OTHER COUNTIES SHOULD BE ABLE TO HANDLE THE RAINFALL.
&&
.LONG TERM (THURSDAY THROUGH TUESDAY)...
THE BIG UPPER LOW OVER THE ROCKIES RESPONSIBLE FOR ALL OF OUR RAIN
ACTIVITY LATELY WILL BEGIN TO FINALLY SHIFT EASTWARD THURSDAY AND
PROGRESS ACROSS THE CENTRAL UNITED STATES. THIS SHOULD QUICKLY
TRANSITION THE UPPER LEVEL PATTERN FOR THE REGION INTO A NORTHWEST
FLOW SITUATION. ANOTHER SHORTWAVE WILL PASS INTO THE RED RIVER
VALLEY AND INTO THE ARKLATEX THURSDAY AS WELL. THIS WILL BRING
ANOTHER SHOT AT SHOWERS AND STORMS THURSDAY AFTERNOON AND EVENING
FAVORING THE NORTHERN AND EASTERN ZONES YET AGAIN.
A COLD FRONT WILL PUSH THROUGH THE AREA LATE THURSDAY NIGHT BEHIND
THE QPF REPLACING THE AIR MASS WITH MUCH DRIER AIR FRIDAY. A BRIEF
DRY PERIOD WILL EXIST THROUGH SATURDAY AFTERNOON WHEN A WEAK
SHORTWAVE COMES ACROSS THE STATE THIS WEEKEND WITH THE NEXT POP
OPPORTUNITY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 66 79 65 79 60 / 50 60 30 40 20
AUSTIN BERGSTROM INTL AIRPORT 66 79 64 79 59 / 50 60 30 40 20
NEW BRAUNFELS MUNI AIRPORT 66 80 64 80 61 / 40 60 30 40 30
BURNET MUNI AIRPORT 63 78 62 78 57 / 50 40 30 40 20
DEL RIO INTL AIRPORT 65 83 66 85 62 / 40 30 20 20 20
GEORGETOWN MUNI AIRPORT 65 78 63 78 58 / 50 60 30 40 20
HONDO MUNI AIRPORT 65 82 65 84 61 / 40 30 30 30 20
SAN MARCOS MUNI AIRPORT 66 79 65 79 60 / 50 60 30 40 30
LA GRANGE - FAYETTE REGIONAL 68 78 65 79 61 / 50 60 30 50 30
SAN ANTONIO INTL AIRPORT 66 81 66 81 63 / 40 50 30 40 20
STINSON MUNI AIRPORT 68 82 67 82 63 / 40 40 30 40 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR THE FOLLOWING
COUNTIES: BASTROP...CALDWELL...DE WITT...FAYETTE...GONZALES...
LAVACA...LEE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...TB3
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1227 PM CDT TUE APR 19 2016
.DISCUSSION...
18Z AVIATION...SEEING ISOLATED SHRA ALONG AND EAST OF A LBX TO
IAH LINE. WITH ADDITIONAL DAYTIME HEATING SHOULD SEE SHRA
COVERAGE EXPAND AND ISO TSRA DEVELOPING AROUND 20Z. THE MAIN
CONCERN IS THE POTENTIAL FOR A LINE OF TSRA TOMORROW MORNING
MOVING EAST ACROSS SE TX DURING THE 9Z TO 18Z PD. CONFIDENCE IS
NOT HIGH ON THIS HAPPENING...BUT WORTHY OF A PROB30 ATTM. WILL SEE
WIDESPREAD MVFR CEILINGS AND POSSIBLY IFR CEILINGS TONIGHT INTO
WED AM. 33
&&
.PREV DISCUSSION... /ISSUED 955 AM CDT TUE APR 19 2016/
DISCUSSION...
SE TX WAS STILL UNDER THE INFLUENCE OF MOISTURE STREAMING IN FROM
THE PACIFIC AROUND AN UPPER LOW LOCATED OVER THE PLAINS. AT 9 AM A
SURFACE TROUGH WAS LOCATED ALONG THE IMMEDIATE COAST WITH AN UPPER
LEVEL SHORTWAVE TROUGH MOVING INTO SE TX FROM THE SOUTH. SCATTERED
SHOWERS AND THUNDERSTORMS WERE OCCURRING OVER CHAMBERS AND LIBERTY
COUNTIES IN ASSOCIATION WITH THIS UPPER LEVEL SYSTEM. HIGH
RESOLUTION MODELS PICKED UP ON THIS SYSTEM. LATER THIS AFTERNOON
BEST CHANCES OF RAIN WILL BE ALONG THE COAST AND GALVESTON BAY.
SCATTERED CHANCES WILL BE FURTHER INLAND MAINLY NORTH OF THE
INTERSTATE 10 CORRIDOR NEAR THE COAST AND POINTS WEST.
40
PREV DISCUSSION... /ISSUED 644 AM CDT TUE APR 19 2016/
AVIATION...
STARTING THE MORNING OFF WITH SOME IFR CEILINGS AND VISIBILITIES IN
AND AROUND CLL AND UTS WITH SOME MVFR DECKS FURTHER SOUTH TOWARD THE
COAST. GENERALLY EXPECT TO SEE MVFR CEILINGS TODAY WITH SHRA POSSIBLE
THIS MORNING AND TSRA POSSIBLE THIS AFTERNOON. BEST COVERAGE MIGHT END
UP BEING BETWEEN IAH AND GLS. ANTICIPATE A BREAK TONIGHT WHICH COULD
ALLOW FOR A POSSIBLE LOWERING OF AREA CEILINGS AND VISIBILITIES INTO
IFR LEVELS. LOOKS LIKE THE AREA COULD GET ANOTHER SHOT OF SHRA/TSRA
DURING THE DAY ON WEDNESDAY AS AN EASTWARD/SOUTHEASTWARD MOVING STORM
COMPLEX MOVES ACROSS THE AREA. 42
PREV DISCUSSION... /ISSUED 501 AM CDT TUE APR 19 2016/
FLASH FLOOD WATCH TO CONTINUE TODAY...
DISCUSSION...
AFTER A LONG MORNING ON THE WARNING DESK YESTERDAY...BACK AT THE
FORECAST DESK ONE MORE TIME. AREA RADAR ARE RATHER QUIET COMPARED
TO 24 HOURS AGO. SURFACE OBSERVATIONS SHOWING SOME PATCHY FOG WITH
OVERALL STABLE BOUNDARY LAYER MAINLY FROM BRENHAM TO COLLEGE
STATION OVER TO HUNTSVILLE. SURFACE ANALYSIS ALSO SHOWS 70
DEWPOINTS JUST OFF THE COAST WHICH MAY STILL ADVECT INLAND DESPITE
A WEAK PRESSURE GRADIENT. VAD WIND PROFILES AT THE KHGX 88D SHOW
30-35KTS JUST 2000-5000FT AGL VEERING FROM S TO SW WHICH SUGGESTS
WARM ADVECTION PATTERN. ALOFT LOOKING AT WATER VAPOR
IMAGERY...CLOSED UPPER LEVEL LOW WAS LOCATED OVER THE CENTRAL AND
NORTH ROCKIES. UPPER LEVEL RIDGE HAS WEAKENED OVER THE MISSISSIPPI
AND OHIO RIVER VALLEYS WHILE A RIDGE HAS STRENGTHENED OVER THE
PACIFIC COAST. IT APPEARS THAT THIS BLOCKING PATTERN MAY BE IN THE
PROCESS OF BREAKING DOWN THE NEXT COUPLE OF DAYS. SYNOPTIC MODELS
SEEM ON TRACK WITH THIS SCENARIO.
TODAY LOOKS LIKE MORE OF A RECOVERY DAY FOR THE ATMOSPHERE. BUT AS
NOTED WITH THE VAD WIND PROFILE...COULD SEE AN INFLUX OF MOISTURE
ALONG THE COAST LATER THIS MORNING AND FURTHER INLAND LATER THIS
AFTERNOON. WATER VAPOR IMAGERY SHOWS WHAT LOOKS LIKE A COUPLE OF
WEEK SHORT WAVE TROUGHS THAT COULD BE ON TRACK TO MOVE OVER THE
AREA TODAY SUPPORT AT LEAST SOME BROAD LARGE SCALE ASCENT. IT IS
HARD TO TELL IF THE MODELS ARE RESOLVING ANY OF THESE FEATURES OR
NOT. MESOSCALE MODELS LIKE THE HRRR AND THE TEXAS TECH WRF SHOW
THUNDERSTORM DEVELOPMENT LATER IN THE MORNING ALONG THE COAST AND
THEN INLAND. LOOKS LIKE CONVECTIVE INITIATION MAY BE ALONG A
BOUNDARY MOVING NORTH OUT OF THE GULF. WRF-ARW HAS A HINT OF THIS
AS WELL BUT NOT AS PRONOUNCED. RIGHT NOW THINK A GENERAL 40-60
PERCENT RAIN CHANCE WILL COVER THE POSSIBILITY OF SCATTERED
ACTIVITY. JUST WORRIED THAT IF SOME OF THESE STORMS GET A BIT MORE
ORGANIZED THEN WE WILL SEE RAIN RATES BACK IN THE 1-2 INCH AN HOUR
RANGE. PRECIP WATER VALUES ARE STILL EXPECTED TO BE AROUND 1.6-1.7
INCHES. BASED ON UPWIND CORFIDI VECTORS...STORM MOTIONS WILL BE
ON THE SLOW SIDE SO A LOCALIZED SPOT OF 2-3 INCHES OF RAIN WILL BE
POSSIBLE. IT IS FOR THIS REASON WE WILL CONTINUE THE FLASH FLOOD
WATCH UNTIL 12Z WEDNESDAY.
THE FLASH FLOOD WATCH MAY NEED TO BE EXTENDED THROUGH WEDNESDAY.
LOOKS LIKE GFS/NAM AND THEN HIGH RES WRF MODELS WANT TO BRING A
SQUALL LINE/MCS INTO SE TX LATE TONIGHT INTO WEDNESDAY MORNING.
GFS SHOWS PRECIP WATER VALUES GOING UP TO 1.8 INCHES WITH S/SW
BOUNDARY LAYER FLOW AROUND 20-30KTS. THIS WOULD CERTAINLY SUPPORT
MORE HEAVY RAINFALL. A STRONG SHORT WAVE TROUGH ALSO ROUNDS THE
BASE OF THE MAIN UPPER LOW NOW OVER THE PLAINS THROUGH THURSDAY. A
COLD FRONT WORKS INTO THE AREA DURING THIS TIME AND MAY BE THE
FOCUS FOR MORE RAINFALL. HATE TO SOUND LIKE A BROKEN RECORD BUT AT
LEAST ANOTHER CHANCE FOR THE FLASH FLOOD WATCH TO BE EXTENDED.
RAINFALL AMOUNTS FOR THE NEXT 3 DAYS ARE IN THE NEIGHBORHOOD OF 2
TO 4 INCHES WITH OBVIOUSLY LOCALLY HIGHER AMOUNTS.
COLD FRONT WORKS THROUGH THE AREA THURSDAY NIGHT SO EXPECT SOME
DRIER CONDITIONS OVER THE WEEKEND. WARM AIR ADVECTION PATTERN SETS
UP AGAIN SUNDAY INTO EARLY NEXT WEEK WHICH WILL SUPPORT SOME LOW
20-30 PERCENT RAIN CHANCES.
39
MARINE...
LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND
THUNDERSTORMS WILL PERSIST UNTIL THURSDAY NIGHT WHEN A COLD FRONT
MOVES THROUGH THE AREA. THE LIGHT TO MODERATE OFFSHORE WINDS BEHIND
THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS
RETURN TO THE AREA ON SATURDAY OR SATURDAY NIGHT AND STRENGTHEN ON
SUNDAY AND MONDAY. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 67 78 66 79 60 / 40 70 40 50 30
HOUSTON (IAH) 67 78 67 81 63 / 40 70 40 60 30
GALVESTON (GLS) 70 76 70 78 68 / 30 60 30 40 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...NONE.
&&
$$
DISCUSSION...33
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
1214 PM CDT TUE APR 19 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...SURFACE HIGH PRESSURE CENTERED OVER DEEP SOUTH TEXAS
COMBINED WITH A STABILIZED ATMOSPHERE FROM LAST NIGHT`S
THUNDERSTORM ACTIVITY IS BRINGING VFR CONDITIONS TO THE ENTIRE
REGION. VFR CONDITIONS TO PREVAIL THROUGH ROUGHLY 05Z THIS
EVENING WHEN MVFR CIGS WILL BEGIN TO DEVELOP ACROSS PORTIONS OF
THE FORECAST AREA. MAY ALSO SEE SOME ISOLATED THUNDERSTORMS MAINLY
WEST OF HIGHWAY 281 AFTER 22Z THIS AFTERNOON AND CONTINUING INTO
THIS EVENING. VFR CONDITIONS TO RETURN TO THE REGION AFTER 16Z
WEDNESDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 632 AM CDT TUE APR 19 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CONFIDENCE IN PRECIPITATION FOR TODAY HAS DECREASED AS
06Z MODEL GUIDANCE AND MOST RECENT HIGH RESOLUTION MODEL GUIDANCE
KEEPS THE AREA STABILIZED THROUGH MUCH OF THE DAY WITH LITTLE IF
ANY PRECIPITATION ACROSS DEEP SOUTH TEXAS. THEREFORE HAVE REMOVED
MENTION OF PRECIPITATION FROM THE TAFS. MFE HAS RECENTLY BEEN
IMPACTED BY LIFR CIGS WHICH SHOULD LAST THROUGH MID MORNING.
OTHERWISE THE TAF SITE WILL BE VFR TODAY. WESTERLY WINDS
CURRENTLY BEHIND A WAKE LOW FROM EARLY THIS MORNING WILL
EVENTUALLY BECOME SOUTHEASTERLY LATE THIS MORNING WITH A FEW GUSTS
TO 20 KNOTS. TONIGHT MVFR CIGS WILL DEVELOP ACROSS MUCH OF THE
VALLEY. FOG SHOULD NOT BE AN ISSUE AS SFC WINDS WILL REMAIN
ELEVATED AROUND 8-10 KNOTS.
PREV DISCUSSION... /ISSUED 352 AM CDT TUE APR 19 2016/
SHORT TERM /TODAY THROUGH WEDNESDAY/...OVERNIGHT CONVECTION HAS
CLEARED THE COAST AND ASSOCIATED WAKE LOW DEVELOPED AND DROVE WINDS
UP AS IT DEPARTED OFF THE COAST. WIND GUSTS REACHED 52 KNOTS AT
VALLEY INTERNATIONAL AIRPORT AND 47 KNOTS AT BROWNSVILLE SOUTH PADRE
ISLAND INTERNATIONAL AIRPORT. ATMOSPHERE IS WORKED OVER AND
STABILIZED PER THE HRRR AND LITTLE IF ANY PRECIPITATION IS EXPECTED
THROUGH LATE MORNING.
UPPER AIR PATTERN IS CHARACTERIZED BY A SLOW MOVING UPPER LOW ACROSS
THE CENTRAL ROCKIES WITH A WEAKENING RIDGE TO THE EAST OF THIS
FEATURE. THE RIDGE WILL BEGIN TO MOVE EASTWARD AND THE UPPER LOW
WILL DO THE SAME AND WEAKEN AS IT MAKES IT ACROSS THE CENTRAL PLAINS.
THE SURFACE PATTERN WILL BE CHARACTERIZED BY MAINLY EAST TO
SOUTHEAST WINDS AND A WEAK INVERTED TROUGH ACROSS SOUTH TEXAS.
MOISTURE WILL REMAIN HIGH WITH PWATS OF 1.6 TO 1.8 INCHES IN THE
SHORT TERM.
THERE WILL BE A WEAK PERTURBATION TO MOVE THROUGH THE FLOW THIS
AFTERNOON...ALONG WITH WEAK DIFFLUENCE ALOFT...SHOULD KICK OFF
ISOLATED TO SCATTERED SHOWERS AND STORMS. CURRENT 30/40 POPS THIS
AFTERNOON AND TONIGHT LOOK REASONABLE. THERE IS SOME DISCREPANCIES
BETWEEN THE MODELS ON LOCATIONS OF PRECIPITATION SO CONFIDENCE IS ON
THE LOW SIDE TODAY CONCERNING PRECIPITATION. EXPECT PRECIPITATION TO
GET STARTED ALONG THE COAST WHERE BEST MOISTURE AND LOW LEVEL
CONVERGENCE RESIDES THEN DEVELOP INLAND AS THE PERTURBATION MOVES
OVERHEAD.
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...H5 TROUGH FINALLY
OPENS UP AND MOVES EAST WEDNESDAY NIGHT AS THE BLOCKING PATTERN
RELEASES SOMEWHAT ACROSS THE WESTERN HEMISPHERE. WHILE
INSTABILITY ALOFT IS DECREASED...DEEP MOISTURE REMAINS IN PLACE
ACROSS SOUTH TEXAS... WITH PW VALUES BETWEEN 1.5 AND 1.7 THURSDAY
AFTERNOON. WITH FORECAST HIGHS IN THE UPPER 80S AND LOWER
90S...THE SEABREEZE SHOULD BE ABLE TO SPARK WIDELY SCATTERED
SHOWERS MAINLY DURING PEAK HEATING HOURS. MORE TRANQUIL CONDITIONS
ARE FORECAST ON THURSDAY AS WEAK RIDGING MOVES THROUGH
ALOFT...FURTHER STABILIZING THE ATMOSPHERE. A FEW SEABREEZE TYPE
SHOWERS ARE STILL POSSIBLE...BUT WOULD BE ISOLATED. SATURDAY THE
NEXT H5 TROUGH COMES ASHORE AND INTO THE FOUR CORNERS REGION.
DIFFLUENCE AHEAD OF THIS SYSTEM WILL BRING GOOD INSTABILITY TO THE
MOUNTAINS IN MEXICO. WITH GULF MOISTURE STILL IN THE
REGION...THUNDERSTORMS HAVE A GOOD CHANCE TO MOVE INTO THE
WESTERN COUNTIES LATE SATURDAY AFTERNOON INTO THE EVENING. AFTER
SATURDAY...MODELS DIVERGE CONSIDERABLY WITH REGARD TO THE NEXT H5
TROUGH...SO FORECAST CONFIDENCE INTO EARLY NEXT WEEK IS LOWERED.
IT DOES LOOK AS THOUGH A GOOD PUSH OF DRIER AIR MOVES INTO THE
REGION...WHICH WOULD BRING AN END TO THIS CURRENT WET REGIME.
MARINE...
NOW THROUGH WEDNESDAY...SSE WINDS AT 10 KNOTS AND SEAS AROUND 7 FEET
WERE REPORTED AT BUOY 42020 EARLY THIS MORNING. NORTHERN FRINGES OF
OVERNIGHT MCS WERE MOVING THROUGH THE SOUTHERN COASTAL WATERS AS OF
THIS WRITING. THIS WILL CAUSE LOCALLY HIGHER WINDS AND SEAS AS THIS
AREA PASSES BY. WINDS WILL GENERALLY BE MODERATE TODAY WITH LONG
FETCH OF EASTERLY WAVES KEEPING SEA HEIGHTS AROUND 7 FEET. SCA IS
EXTENDED THROUGH 7 PM THIS EVENING. MODERATE WINDS AND DIMINISHING
SEA HEIGHTS ARE EXPECTED WEDNESDAY.
BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ150-155-
170-175.
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
19/67
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
955 AM CDT TUE APR 19 2016
.DISCUSSION...
SE TX WAS STILL UNDER THE INFLUENCE OF MOISTURE STREAMING IN FROM
THE PACIFIC AROUND AN UPPER LOW LOCATED OVER THE PLAINS. AT 9 AM A
SURFACE TROUGH WAS LOCATED ALONG THE IMMEDIATE COAST WITH AN UPPER
LEVEL SHORTWAVE TROUGH MOVING INTO SE TX FROM THE SOUTH. SCATTERED
SHOWERS AND THUNDERSTORMS WERE OCCURRING OVER CHAMBERS AND LIBERTY
COUNTIES IN ASSOCIATION WITH THIS UPPER LEVEL SYSTEM. HIGH
RESOLUTION MODELS PICKED UP ON THIS SYSTEM. LATER THIS AFTERNOON
BEST CHANCES OF RAIN WILL BE ALONG THE COAST AND GALVESTON BAY.
SCATTERED CHANCES WILL BE FURTHER INLAND MAINLY NORTH OF THE
INTERSTATE 10 CORRIDOR NEAR THE COAST AND POINTS WEST.
40
&&
.PREV DISCUSSION... /ISSUED 644 AM CDT TUE APR 19 2016/
AVIATION...
STARTING THE MORNING OFF WITH SOME IFR CEILINGS AND VISIBILITIES IN
AND AROUND CLL AND UTS WITH SOME MVFR DECKS FURTHER SOUTH TOWARD THE
COAST. GENERALLY EXPECT TO SEE MVFR CEILINGS TODAY WITH SHRA POSSIBLE
THIS MORNING AND TSRA POSSIBLE THIS AFTERNOON. BEST COVERAGE MIGHT END
UP BEING BETWEEN IAH AND GLS. ANTICIPATE A BREAK TONIGHT WHICH COULD
ALLOW FOR A POSSIBLE LOWERING OF AREA CEILINGS AND VISIBILITIES INTO
IFR LEVELS. LOOKS LIKE THE AREA COULD GET ANOTHER SHOT OF SHRA/TSRA
DURING THE DAY ON WEDNESDAY AS AN EASTWARD/SOUTHEASTWARD MOVING STORM
COMPLEX MOVES ACROSS THE AREA. 42
PREV DISCUSSION... /ISSUED 501 AM CDT TUE APR 19 2016/
.FLASH FLOOD WATCH TO CONTINUE TODAY...
DISCUSSION...
AFTER A LONG MORNING ON THE WARNING DESK YESTERDAY...BACK AT THE
FORECAST DESK ONE MORE TIME. AREA RADAR ARE RATHER QUIET COMPARED
TO 24 HOURS AGO. SURFACE OBSERVATIONS SHOWING SOME PATCHY FOG WITH
OVERALL STABLE BOUNDARY LAYER MAINLY FROM BRENHAM TO COLLEGE
STATION OVER TO HUNTSVILLE. SURFACE ANALYSIS ALSO SHOWS 70
DEWPOINTS JUST OFF THE COAST WHICH MAY STILL ADVECT INLAND DESPITE
A WEAK PRESSURE GRADIENT. VAD WIND PROFILES AT THE KHGX 88D SHOW
30-35KTS JUST 2000-5000FT AGL VEERING FROM S TO SW WHICH SUGGESTS
WARM ADVECTION PATTERN. ALOFT LOOKING AT WATER VAPOR
IMAGERY...CLOSED UPPER LEVEL LOW WAS LOCATED OVER THE CENTRAL AND
NORTH ROCKIES. UPPER LEVEL RIDGE HAS WEAKENED OVER THE MISSISSIPPI
AND OHIO RIVER VALLEYS WHILE A RIDGE HAS STRENGTHENED OVER THE
PACIFIC COAST. IT APPEARS THAT THIS BLOCKING PATTERN MAY BE IN THE
PROCESS OF BREAKING DOWN THE NEXT COUPLE OF DAYS. SYNOPTIC MODELS
SEEM ON TRACK WITH THIS SCENARIO.
TODAY LOOKS LIKE MORE OF A RECOVERY DAY FOR THE ATMOSPHERE. BUT AS
NOTED WITH THE VAD WIND PROFILE...COULD SEE AN INFLUX OF MOISTURE
ALONG THE COAST LATER THIS MORNING AND FURTHER INLAND LATER THIS
AFTERNOON. WATER VAPOR IMAGERY SHOWS WHAT LOOKS LIKE A COUPLE OF
WEEK SHORT WAVE TROUGHS THAT COULD BE ON TRACK TO MOVE OVER THE
AREA TODAY SUPPORT AT LEAST SOME BROAD LARGE SCALE ASCENT. IT IS
HARD TO TELL IF THE MODELS ARE RESOLVING ANY OF THESE FEATURES OR
NOT. MESOSCALE MODELS LIKE THE HRRR AND THE TEXAS TECH WRF SHOW
THUNDERSTORM DEVELOPMENT LATER IN THE MORNING ALONG THE COAST AND
THEN INLAND. LOOKS LIKE CONVECTIVE INITIATION MAY BE ALONG A
BOUNDARY MOVING NORTH OUT OF THE GULF. WRF-ARW HAS A HINT OF THIS
AS WELL BUT NOT AS PRONOUNCED. RIGHT NOW THINK A GENERAL 40-60
PERCENT RAIN CHANCE WILL COVER THE POSSIBILITY OF SCATTERED
ACTIVITY. JUST WORRIED THAT IF SOME OF THESE STORMS GET A BIT MORE
ORGANIZED THEN WE WILL SEE RAIN RATES BACK IN THE 1-2 INCH AN HOUR
RANGE. PRECIP WATER VALUES ARE STILL EXPECTED TO BE AROUND 1.6-1.7
INCHES. BASED ON UPWIND CORFIDI VECTORS...STORM MOTIONS WILL BE
ON THE SLOW SIDE SO A LOCALIZED SPOT OF 2-3 INCHES OF RAIN WILL BE
POSSIBLE. IT IS FOR THIS REASON WE WILL CONTINUE THE FLASH FLOOD
WATCH UNTIL 12Z WEDNESDAY.
THE FLASH FLOOD WATCH MAY NEED TO BE EXTENDED THROUGH WEDNESDAY.
LOOKS LIKE GFS/NAM AND THEN HIGH RES WRF MODELS WANT TO BRING A
SQUALL LINE/MCS INTO SE TX LATE TONIGHT INTO WEDNESDAY MORNING.
GFS SHOWS PRECIP WATER VALUES GOING UP TO 1.8 INCHES WITH S/SW
BOUNDARY LAYER FLOW AROUND 20-30KTS. THIS WOULD CERTAINLY SUPPORT
MORE HEAVY RAINFALL. A STRONG SHORT WAVE TROUGH ALSO ROUNDS THE
BASE OF THE MAIN UPPER LOW NOW OVER THE PLAINS THROUGH THURSDAY. A
COLD FRONT WORKS INTO THE AREA DURING THIS TIME AND MAY BE THE
FOCUS FOR MORE RAINFALL. HATE TO SOUND LIKE A BROKEN RECORD BUT AT
LEAST ANOTHER CHANCE FOR THE FLASH FLOOD WATCH TO BE EXTENDED.
RAINFALL AMOUNTS FOR THE NEXT 3 DAYS ARE IN THE NEIGHBORHOOD OF 2
TO 4 INCHES WITH OBVIOUSLY LOCALLY HIGHER AMOUNTS.
COLD FRONT WORKS THROUGH THE AREA THURSDAY NIGHT SO EXPECT SOME
DRIER CONDITIONS OVER THE WEEKEND. WARM AIR ADVECTION PATTERN SETS
UP AGAIN SUNDAY INTO EARLY NEXT WEEK WHICH WILL SUPPORT SOME LOW
20-30 PERCENT RAIN CHANCES.
39
MARINE...
LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND
THUNDERSTORMS WILL PERSIST UNTIL THURSDAY NIGHT WHEN A COLD FRONT
MOVES THROUGH THE AREA. THE LIGHT TO MODERATE OFFSHORE WINDS BEHIND
THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS
RETURN TO THE AREA ON SATURDAY OR SATURDAY NIGHT AND STRENGTHEN ON
SUNDAY AND MONDAY. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 76 67 78 66 79 / 40 40 70 40 50
HOUSTON (IAH) 74 67 78 67 81 / 50 40 70 40 60
GALVESTON (GLS) 73 70 76 70 78 / 50 30 60 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...NONE.
&&
$$
DISCUSSION...40
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
644 AM CDT TUE APR 19 2016
.AVIATION...
STARTING THE MORNING OFF WITH SOME IFR CEILINGS AND VISIBILITIES IN
AND AROUND CLL AND UTS WITH SOME MVFR DECKS FURTHER SOUTH TOWARD THE
COAST. GENERALLY EXPECT TO SEE MVFR CEILINGS TODAY WITH SHRA POSSIBLE
THIS MORNING AND TSRA POSSIBLE THIS AFTERNOON. BEST COVERAGE MIGHT END
UP BEING BETWEEN IAH AND GLS. ANTICIPATE A BREAK TONIGHT WHICH COULD
ALLOW FOR A POSSIBLE LOWERING OF AREA CEILINGS AND VISIBILITIES INTO
IFR LEVELS. LOOKS LIKE THE AREA COULD GET ANOTHER SHOT OF SHRA/TSRA
DURING THE DAY ON WEDNESDAY AS AN EASTWARD/SOUTHEASTWARD MOVING STORM
COMPLEX MOVES ACROSS THE AREA. 42
&&
.PREV DISCUSSION... /ISSUED 501 AM CDT TUE APR 19 2016/
..FLASH FLOOD WATCH TO CONTINUE TODAY...
DISCUSSION...
AFTER A LONG MORNING ON THE WARNING DESK YESTERDAY...BACK AT THE
FORECAST DESK ONE MORE TIME. AREA RADAR ARE RATHER QUIET COMPARED
TO 24 HOURS AGO. SURFACE OBSERVATIONS SHOWING SOME PATCHY FOG WITH
OVERALL STABLE BOUNDARY LAYER MAINLY FROM BRENHAM TO COLLEGE
STATION OVER TO HUNTSVILLE. SURFACE ANALYSIS ALSO SHOWS 70
DEWPOINTS JUST OFF THE COAST WHICH MAY STILL ADVECT INLAND DESPITE
A WEAK PRESSURE GRADIENT. VAD WIND PROFILES AT THE KHGX 88D SHOW
30-35KTS JUST 2000-5000FT AGL VEERING FROM S TO SW WHICH SUGGESTS
WARM ADVECTION PATTERN. ALOFT LOOKING AT WATER VAPOR
IMAGERY...CLOSED UPPER LEVEL LOW WAS LOCATED OVER THE CENTRAL AND
NORTH ROCKIES. UPPER LEVEL RIDGE HAS WEAKENED OVER THE MISSISSIPPI
AND OHIO RIVER VALLEYS WHILE A RIDGE HAS STRENGTHENED OVER THE
PACIFIC COAST. IT APPEARS THAT THIS BLOCKING PATTERN MAY BE IN THE
PROCESS OF BREAKING DOWN THE NEXT COUPLE OF DAYS. SYNOPTIC MODELS
SEEM ON TRACK WITH THIS SCENARIO.
TODAY LOOKS LIKE MORE OF A RECOVERY DAY FOR THE ATMOSPHERE. BUT AS
NOTED WITH THE VAD WIND PROFILE...COULD SEE AN INFLUX OF MOISTURE
ALONG THE COAST LATER THIS MORNING AND FURTHER INLAND LATER THIS
AFTERNOON. WATER VAPOR IMAGERY SHOWS WHAT LOOKS LIKE A COUPLE OF
WEEK SHORT WAVE TROUGHS THAT COULD BE ON TRACK TO MOVE OVER THE
AREA TODAY SUPPORT AT LEAST SOME BROAD LARGE SCALE ASCENT. IT IS
HARD TO TELL IF THE MODELS ARE RESOLVING ANY OF THESE FEATURES OR
NOT. MESOSCALE MODELS LIKE THE HRRR AND THE TEXAS TECH WRF SHOW
THUNDERSTORM DEVELOPMENT LATER IN THE MORNING ALONG THE COAST AND
THEN INLAND. LOOKS LIKE CONVECTIVE INITIATION MAY BE ALONG A
BOUNDARY MOVING NORTH OUT OF THE GULF. WRF-ARW HAS A HINT OF THIS
AS WELL BUT NOT AS PRONOUNCED. RIGHT NOW THINK A GENERAL 40-60
PERCENT RAIN CHANCE WILL COVER THE POSSIBILITY OF SCATTERED
ACTIVITY. JUST WORRIED THAT IF SOME OF THESE STORMS GET A BIT MORE
ORGANIZED THEN WE WILL SEE RAIN RATES BACK IN THE 1-2 INCH AN HOUR
RANGE. PRECIP WATER VALUES ARE STILL EXPECTED TO BE AROUND 1.6-1.7
INCHES. BASED ON UPWIND CORFIDI VECTORS...STORM MOTIONS WILL BE
ON THE SLOW SIDE SO A LOCALIZED SPOT OF 2-3 INCHES OF RAIN WILL BE
POSSIBLE. IT IS FOR THIS REASON WE WILL CONTINUE THE FLASH FLOOD
WATCH UNTIL 12Z WEDNESDAY.
THE FLASH FLOOD WATCH MAY NEED TO BE EXTENDED THROUGH WEDNESDAY.
LOOKS LIKE GFS/NAM AND THEN HIGH RES WRF MODELS WANT TO BRING A
SQUALL LINE/MCS INTO SE TX LATE TONIGHT INTO WEDNESDAY MORNING.
GFS SHOWS PRECIP WATER VALUES GOING UP TO 1.8 INCHES WITH S/SW
BOUNDARY LAYER FLOW AROUND 20-30KTS. THIS WOULD CERTAINLY SUPPORT
MORE HEAVY RAINFALL. A STRONG SHORT WAVE TROUGH ALSO ROUNDS THE
BASE OF THE MAIN UPPER LOW NOW OVER THE PLAINS THROUGH THURSDAY. A
COLD FRONT WORKS INTO THE AREA DURING THIS TIME AND MAY BE THE
FOCUS FOR MORE RAINFALL. HATE TO SOUND LIKE A BROKEN RECORD BUT AT
LEAST ANOTHER CHANCE FOR THE FLASH FLOOD WATCH TO BE EXTENDED.
RAINFALL AMOUNTS FOR THE NEXT 3 DAYS ARE IN THE NEIGHBORHOOD OF 2
TO 4 INCHES WITH OBVIOUSLY LOCALLY HIGHER AMOUNTS.
COLD FRONT WORKS THROUGH THE AREA THURSDAY NIGHT SO EXPECT SOME
DRIER CONDITIONS OVER THE WEEKEND. WARM AIR ADVECTION PATTERN SETS
UP AGAIN SUNDAY INTO EARLY NEXT WEEK WHICH WILL SUPPORT SOME LOW
20-30 PERCENT RAIN CHANCES.
39
MARINE...
LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND
THUNDERSTORMS WILL PERSIST UNTIL THURSDAY NIGHT WHEN A COLD FRONT
MOVES THROUGH THE AREA. THE LIGHT TO MODERATE OFFSHORE WINDS BEHIND
THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS
RETURN TO THE AREA ON SATURDAY OR SATURDAY NIGHT AND STRENGTHEN ON
SUNDAY AND MONDAY. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 67 78 66 79 / 40 40 70 40 50
HOUSTON (IAH) 78 67 78 67 81 / 50 40 70 40 60
GALVESTON (GLS) 76 70 76 70 78 / 50 30 60 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 7 AM CDT THIS MORNING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
632 AM CDT TUE APR 19 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...CONFIDENCE IN PRECIPITATION FOR TODAY HAS DECREASED AS
06Z MODEL GUIDANCE AND MOST RECENT HIGH RESOLUTION MODEL GUIDANCE
KEEPS THE AREA STABILIZED THROUGH MUCH OF THE DAY WITH LITTLE IF
ANY PRECIPITATION ACROSS DEEP SOUTH TEXAS. THEREFORE HAVE REMOVED
MENTION OF PRECIPITATION FROM THE TAFS. MFE HAS RECENTLY BEEN
IMPACTED BY LIFR CIGS WHICH SHOULD LAST THROUGH MID MORNING.
OTHERWISE THE TAF SITE WILL BE VFR TODAY. WESTERLY WINDS
CURRENTLY BEHIND A WAKE LOW FROM EARLY THIS MORNING WILL
EVENTUALLY BECOME SOUTHEASTERLY LATE THIS MORNING WITH A FEW GUSTS
TO 20 KNOTS. TONIGHT MVFR CIGS WILL DEVELOP ACROSS MUCH OF THE
VALLEY. FOG SHOULD NOT BE AN ISSUE AS SFC WINDS WILL REMAIN
ELEVATED AROUND 8-10 KNOTS.
&&
.PREV DISCUSSION... /ISSUED 352 AM CDT TUE APR 19 2016/
SHORT TERM /TODAY THROUGH WEDNESDAY/...OVERNIGHT CONVECTION HAS
CLEARED THE COAST AND ASSOCIATED WAKE LOW DEVELOPED AND DROVE WINDS
UP AS IT DEPARTED OFF THE COAST. WIND GUSTS REACHED 52 KNOTS AT
VALLEY INTERNATIONAL AIRPORT AND 47 KNOTS AT BROWNSVILLE SOUTH PADRE
ISLAND INTERNATIONAL AIRPORT. ATMOSPHERE IS WORKED OVER AND
STABILIZED PER THE HRRR AND LITTLE IF ANY PRECIPITATION IS EXPECTED
THROUGH LATE MORNING.
UPPER AIR PATTERN IS CHARACTERIZED BY A SLOW MOVING UPPER LOW ACROSS
THE CENTRAL ROCKIES WITH A WEAKENING RIDGE TO THE EAST OF THIS
FEATURE. THE RIDGE WILL BEGIN TO MOVE EASTWARD AND THE UPPER LOW
WILL DO THE SAME AND WEAKEN AS IT MAKES IT ACROSS THE CENTRAL PLAINS.
THE SURFACE PATTERN WILL BE CHARACTERIZED BY MAINLY EAST TO
SOUTHEAST WINDS AND A WEAK INVERTED TROUGH ACROSS SOUTH TEXAS.
MOISTURE WILL REMAIN HIGH WITH PWATS OF 1.6 TO 1.8 INCHES IN THE
SHORT TERM.
THERE WILL BE A WEAK PERTURBATION TO MOVE THROUGH THE FLOW THIS
AFTERNOON...ALONG WITH WEAK DIFFLUENCE ALOFT...SHOULD KICK OFF
ISOLATED TO SCATTERED SHOWERS AND STORMS. CURRENT 30/40 POPS THIS
AFTERNOON AND TONIGHT LOOK REASONABLE. THERE IS SOME DISCREPANCIES
BETWEEN THE MODELS ON LOCATIONS OF PRECIPITATION SO CONFIDENCE IS ON
THE LOW SIDE TODAY CONCERNING PRECIPITATION. EXPECT PRECIPITATION TO
GET STARTED ALONG THE COAST WHERE BEST MOISTURE AND LOW LEVEL
CONVERGENCE RESIDES THEN DEVELOP INLAND AS THE PERTURBATION MOVES
OVERHEAD.
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...H5 TROUGH FINALLY
OPENS UP AND MOVES EAST WEDNESDAY NIGHT AS THE BLOCKING PATTERN
RELEASES SOMEWHAT ACROSS THE WESTERN HEMISPHERE. WHILE
INSTABILITY ALOFT IS DECREASED...DEEP MOISTURE REMAINS IN PLACE
ACROSS SOUTH TEXAS... WITH PW VALUES BETWEEN 1.5 AND 1.7 THURSDAY
AFTERNOON. WITH FORECAST HIGHS IN THE UPPER 80S AND LOWER
90S...THE SEABREEZE SHOULD BE ABLE TO SPARK WIDELY SCATTERED
SHOWERS MAINLY DURING PEAK HEATING HOURS. MORE TRANQUIL CONDITIONS
ARE FORECAST ON THURSDAY AS WEAK RIDGING MOVES THROUGH
ALOFT...FURTHER STABILIZING THE ATMOSPHERE. A FEW SEABREEZE TYPE
SHOWERS ARE STILL POSSIBLE...BUT WOULD BE ISOLATED. SATURDAY THE
NEXT H5 TROUGH COMES ASHORE AND INTO THE FOUR CORNERS REGION.
DIFFLUENCE AHEAD OF THIS SYSTEM WILL BRING GOOD INSTABILITY TO THE
MOUNTAINS IN MEXICO. WITH GULF MOISTURE STILL IN THE
REGION...THUNDERSTORMS HAVE A GOOD CHANCE TO MOVE INTO THE
WESTERN COUNTIES LATE SATURDAY AFTERNOON INTO THE EVENING. AFTER
SATURDAY...MODELS DIVERGE CONSIDERABLY WITH REGARD TO THE NEXT H5
TROUGH...SO FORECAST CONFIDENCE INTO EARLY NEXT WEEK IS LOWERED.
IT DOES LOOK AS THOUGH A GOOD PUSH OF DRIER AIR MOVES INTO THE
REGION...WHICH WOULD BRING AN END TO THIS CURRENT WET REGIME.
MARINE...
NOW THROUGH WEDNESDAY...SSE WINDS AT 10 KNOTS AND SEAS AROUND 7 FEET
WERE REPORTED AT BUOY 42020 EARLY THIS MORNING. NORTHERN FRINGES OF
OVERNIGHT MCS WERE MOVING THROUGH THE SOUTHERN COASTAL WATERS AS OF
THIS WRITING. THIS WILL CAUSE LOCALLY HIGHER WINDS AND SEAS AS THIS
AREA PASSES BY. WINDS WILL GENERALLY BE MODERATE TODAY WITH LONG
FETCH OF EASTERLY WAVES KEEPING SEA HEIGHTS AROUND 7 FEET. SCA IS
EXTENDED THROUGH 7 PM THIS EVENING. MODERATE WINDS AND DIMINISHING
SEA HEIGHTS ARE EXPECTED WEDNESDAY.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ150-155-
170-175.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
55
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
501 AM CDT TUE APR 19 2016
...FLASH FLOOD WATCH TO CONTINUE TODAY...
.DISCUSSION...
AFTER A LONG MORNING ON THE WARNING DESK YESTERDAY...BACK AT THE
FORECAST DESK ONE MORE TIME. AREA RADAR ARE RATHER QUIET COMPARED
TO 24 HOURS AGO. SURFACE OBSERVATIONS SHOWING SOME PATCHY FOG WITH
OVERALL STABLE BOUNDARY LAYER MAINLY FROM BRENHAM TO COLLEGE
STATION OVER TO HUNTSVILLE. SURFACE ANALYSIS ALSO SHOWS 70
DEWPOINTS JUST OFF THE COAST WHICH MAY STILL ADVECT INLAND DESPITE
A WEAK PRESSURE GRADIENT. VAD WIND PROFILES AT THE KHGX 88D SHOW
30-35KTS JUST 2000-5000FT AGL VEERING FROM S TO SW WHICH SUGGESTS
WARM ADVECTION PATTERN. ALOFT LOOKING AT WATER VAPOR
IMAGERY...CLOSED UPPER LEVEL LOW WAS LOCATED OVER THE CENTRAL AND
NORTH ROCKIES. UPPER LEVEL RIDGE HAS WEAKENED OVER THE MISSISSIPPI
AND OHIO RIVER VALLEYS WHILE A RIDGE HAS STRENGTHENED OVER THE
PACIFIC COAST. IT APPEARS THAT THIS BLOCKING PATTERN MAY BE IN THE
PROCESS OF BREAKING DOWN THE NEXT COUPLE OF DAYS. SYNOPTIC MODELS
SEEM ON TRACK WITH THIS SCENARIO.
TODAY LOOKS LIKE MORE OF A RECOVERY DAY FOR THE ATMOSPHERE. BUT AS
NOTED WITH THE VAD WIND PROFILE...COULD SEE AN INFLUX OF MOISTURE
ALONG THE COAST LATER THIS MORNING AND FURTHER INLAND LATER THIS
AFTERNOON. WATER VAPOR IMAGERY SHOWS WHAT LOOKS LIKE A COUPLE OF
WEEK SHORT WAVE TROUGHS THAT COULD BE ON TRACK TO MOVE OVER THE
AREA TODAY SUPPORT AT LEAST SOME BROAD LARGE SCALE ASCENT. IT IS
HARD TO TELL IF THE MODELS ARE RESOLVING ANY OF THESE FEATURES OR
NOT. MESOSCALE MODELS LIKE THE HRRR AND THE TEXAS TECH WRF SHOW
THUNDERSTORM DEVELOPMENT LATER IN THE MORNING ALONG THE COAST AND
THEN INLAND. LOOKS LIKE CONVECTIVE INITIATION MAY BE ALONG A
BOUNDARY MOVING NORTH OUT OF THE GULF. WRF-ARW HAS A HINT OF THIS
AS WELL BUT NOT AS PRONOUNCED. RIGHT NOW THINK A GENERAL 40-60
PERCENT RAIN CHANCE WILL COVER THE POSSIBILITY OF SCATTERED
ACTIVITY. JUST WORRIED THAT IF SOME OF THESE STORMS GET A BIT MORE
ORGANIZED THEN WE WILL SEE RAIN RATES BACK IN THE 1-2 INCH AN HOUR
RANGE. PRECIP WATER VALUES ARE STILL EXPECTED TO BE AROUND 1.6-1.7
INCHES. BASED ON UPWIND CORFIDI VECTORS...STORM MOTIONS WILL BE
ON THE SLOW SIDE SO A LOCALIZED SPOT OF 2-3 INCHES OF RAIN WILL BE
POSSIBLE. IT IS FOR THIS REASON WE WILL CONTINUE THE FLASH FLOOD
WATCH UNTIL 12Z WEDNESDAY.
THE FLASH FLOOD WATCH MAY NEED TO BE EXTENDED THROUGH WEDNESDAY.
LOOKS LIKE GFS/NAM AND THEN HIGH RES WRF MODELS WANT TO BRING A
SQUALL LINE/MCS INTO SE TX LATE TONIGHT INTO WEDNESDAY MORNING.
GFS SHOWS PRECIP WATER VALUES GOING UP TO 1.8 INCHES WITH S/SW
BOUNDARY LAYER FLOW AROUND 20-30KTS. THIS WOULD CERTAINLY SUPPORT
MORE HEAVY RAINFALL. A STRONG SHORT WAVE TROUGH ALSO ROUNDS THE
BASE OF THE MAIN UPPER LOW NOW OVER THE PLAINS THROUGH THURSDAY. A
COLD FRONT WORKS INTO THE AREA DURING THIS TIME AND MAY BE THE
FOCUS FOR MORE RAINFALL. HATE TO SOUND LIKE A BROKEN RECORD BUT AT
LEAST ANOTHER CHANCE FOR THE FLASH FLOOD WATCH TO BE EXTENDED.
RAINFALL AMOUNTS FOR THE NEXT 3 DAYS ARE IN THE NEIGHBORHOOD OF 2
TO 4 INCHES WITH OBVIOUSLY LOCALLY HIGHER AMOUNTS.
COLD FRONT WORKS THROUGH THE AREA THURSDAY NIGHT SO EXPECT SOME
DRIER CONDITIONS OVER THE WEEKEND. WARM AIR ADVECTION PATTERN SETS
UP AGAIN SUNDAY INTO EARLY NEXT WEEK WHICH WILL SUPPORT SOME LOW
20-30 PERCENT RAIN CHANCES.
39
&&
.MARINE...
LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND
THUNDERSTORMS WILL PERSIST UNTIL THURSDAY NIGHT WHEN A COLD FRONT
MOVES THROUGH THE AREA. THE LIGHT TO MODERATE OFFSHORE WINDS BEHIND
THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS
RETURN TO THE AREA ON SATURDAY OR SATURDAY NIGHT AND STRENGTHEN ON
SUNDAY AND MONDAY. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 67 78 66 79 / 40 40 70 40 50
HOUSTON (IAH) 78 67 78 67 81 / 50 40 70 40 60
GALVESTON (GLS) 76 70 76 70 78 / 50 30 60 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 7 AM CDT THIS MORNING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
352 AM CDT TUE APR 19 2016
.SHORT TERM /TODAY THROUGH WEDNESDAY/...OVERNIGHT CONVECTION HAS
CLEARED THE COAST AND ASSOCIATED WAKE LOW DEVELOPED AND DROVE WINDS
UP AS IT DEPARTED OFF THE COAST. WIND GUSTS REACHED 52 KNOTS AT
VALLEY INTERNATIONAL AIRPORT AND 47 KNOTS AT BROWNSVILLE SOUTH PADRE
ISLAND INTERNATIONAL AIRPORT. ATMOSPHERE IS WORKED OVER AND
STABILIZED PER THE HRRR AND LITTLE IF ANY PRECIPITATION IS EXPECTED
THROUGH LATE MORNING.
UPPER AIR PATTERN IS CHARACTERIZED BY A SLOW MOVING UPPER LOW ACROSS
THE CENTRAL ROCKIES WITH A WEAKENING RIDGE TO THE EAST OF THIS
FEATURE. THE RIDGE WILL BEGIN TO MOVE EASTWARD AND THE UPPER LOW
WILL DO THE SAME AND WEAKEN AS IT MAKES IT ACROSS THE CENTRAL PLAINS.
THE SURFACE PATTERN WILL BE CHARACTERIZED BY MAINLY EAST TO
SOUTHEAST WINDS AND A WEAK INVERTED TROUGH ACROSS SOUTH TEXAS.
MOISTURE WILL REMAIN HIGH WITH PWATS OF 1.6 TO 1.8 INCHES IN THE
SHORT TERM.
THERE WILL BE A WEAK PERTURBATION TO MOVE THROUGH THE FLOW THIS
AFTERNOON...ALONG WITH WEAK DIFFLUENCE ALOFT...SHOULD KICK OFF
ISOLATED TO SCATTERED SHOWERS AND STORMS. CURRENT 30/40 POPS THIS
AFTERNOON AND TONIGHT LOOK REASONABLE. THERE IS SOME DISCREPANCIES
BETWEEN THE MODELS ON LOCATIONS OF PRECIPITATION SO CONFIDENCE IS ON
THE LOW SIDE TODAY CONCERNING PRECIPITATION. EXPECT PRECIPITATION TO
GET STARTED ALONG THE COAST WHERE BEST MOISTURE AND LOW LEVEL
CONVERGENCE RESIDES THEN DEVELOP INLAND AS THE PERTURBATION MOVES
OVERHEAD.
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...H5 TROUGH FINALLY
OPENS UP AND MOVES EAST WEDNESDAY NIGHT AS THE BLOCKING PATTERN
RELEASES SOMEWHAT ACROSS THE WESTERN HEMISPHERE. WHILE
INSTABILITY ALOFT IS DECREASED...DEEP MOISTURE REMAINS IN PLACE
ACROSS SOUTH TEXAS... WITH PW VALUES BETWEEN 1.5 AND 1.7 THURSDAY
AFTERNOON. WITH FORECAST HIGHS IN THE UPPER 80S AND LOWER
90S...THE SEABREEZE SHOULD BE ABLE TO SPARK WIDELY SCATTERED
SHOWERS MAINLY DURING PEAK HEATING HOURS. MORE TRANQUIL CONDITIONS
ARE FORECAST ON THURSDAY AS WEAK RIDGING MOVES THROUGH
ALOFT...FURTHER STABILIZING THE ATMOSPHERE. A FEW SEABREEZE TYPE
SHOWERS ARE STILL POSSIBLE...BUT WOULD BE ISOLATED. SATURDAY THE
NEXT H5 TROUGH COMES ASHORE AND INTO THE FOUR CORNERS REGION.
DIFFLUENCE AHEAD OF THIS SYSTEM WILL BRING GOOD INSTABILITY TO THE
MOUNTAINS IN MEXICO. WITH GULF MOISTURE STILL IN THE
REGION...THUNDERSTORMS HAVE A GOOD CHANCE TO MOVE INTO THE
WESTERN COUNTIES LATE SATURDAY AFTERNOON INTO THE EVENING. AFTER
SATURDAY...MODELS DIVERGE CONSIDERABLY WITH REGARD TO THE NEXT H5
TROUGH...SO FORECAST CONFIDENCE INTO EARLY NEXT WEEK IS LOWERED.
IT DOES LOOK AS THOUGH A GOOD PUSH OF DRIER AIR MOVES INTO THE
REGION...WHICH WOULD BRING AN END TO THIS CURRENT WET REGIME.
&&
.MARINE...
NOW THROUGH WEDNESDAY...SSE WINDS AT 10 KNOTS AND SEAS AROUND 7 FEET
WERE REPORTED AT BUOY 42020 EARLY THIS MORNING. NORTHERN FRINGES OF
OVERNIGHT MCS WERE MOVING THROUGH THE SOUTHERN COASTAL WATERS AS OF
THIS WRITING. THIS WILL CAUSE LOCALLY HIGHER WINDS AND SEAS AS THIS
AREA PASSES BY. WINDS WILL GENERALLY BE MODERATE TODAY WITH LONG
FETCH OF EASTERLY WAVES KEEPING SEA HEIGHTS AROUND 7 FEET. SCA IS
EXTENDED THROUGH 7 PM THIS EVENING. MODERATE WINDS AND DIMINISHING
SEA HEIGHTS ARE EXPECTED WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 82 74 84 73 / 40 30 20 30
BROWNSVILLE 84 73 85 72 / 40 30 30 30
HARLINGEN 86 73 87 72 / 40 30 30 30
MCALLEN 88 73 88 72 / 40 40 30 30
RIO GRANDE CITY 89 72 90 71 / 30 40 30 40
SOUTH PADRE ISLAND 78 73 78 72 / 40 30 20 30
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ150-155-
170-175.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
55/64
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
532 AM EDT THU APR 21 2016
.SYNOPSIS...
THE FRONTAL BOUNDARY WILL SHIFT BACK TO THE NORTHEAST TODAY.
INCREASING MOISTURE AND A COLD FRONT WILL APPROACH FROM THE WEST
LATE THURSDAY THROUGH EARLY SATURDAY... BRINGING A CHANCE OF
SHOWERS AND A FEW THUNDERSTORMS...MAINLY DURING FRIDAY AFTERNOON
AND EVENING. DRY HIGH PRESSURE WILL BUILD BACK INTO THE REGION
LATE SATURDAY THROUGH TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY THIS MORNING...ONSHORE FLOW HAS ALLOWED LOW LEVEL MOISTURE
TO MOVE INLAND. LOW STRATUS WILL STRETCH FROM THE CENTRAL MIDLANDS
INTO THE PEE DEE REGION...SCATTERING OUT SHORTLY AFTER SUNRISE AS
DRIER AIR MIXES DOWN. MOISTURE INCREASES AND THE INSULATING STRATUS
WILL KEEP LOW TEMPERATURES IN THE NORTHERN AND CENTRAL MIDLANDS IN
THE UPPER 50S. ELSEWHERE EXPECT LOWS IN THE MID 50S.
TODAY...THE UPPER RIDGE WILL SHIFT OFF THE EAST COAST CREATING A
MORE S/SW FLOW REGIME AND MODERATE WARM ADVECTION ACROSS THE
REGION. THE STALLED FRONTAL BOUNDARY WILL LIFT TO THE NORTHEAST
OUT OF THE FORECAST AREA (FA) TODAY. UPPER LEVEL MOISTURE
ADVECTION AND HIGH CLOUDS WILL CONTINUE TO FLOW OVER THE REGION.
DESPITE PARTLY CLOUDY SKIES...LOCAL FORECAST TOOLS FAVOR THE
WARMER TEMPERATURE GUIDANCE DUE TO WARM ADVECTION AHEAD OF THE
COLD FRONT. EXPECT HIGHS IN THE LOW TO MID 80S.
HI RESOLUTION MODELS SHOW A SEA BREEZE BOUNDARY MOVING INLAND
INTO THE WESTERN FA LATE THIS AFTERNOON/EVENING. MID LEVEL DRY AIR
AND A SMALL CAPPING INVERSION WILL LIMIT CONVECTIVE DEVELOPMENT.
RECENT HRRR MODEL RUNS INDICATE SCATTERED TO ISOLATED SHOWERS
DEVELOPING ALONG THE COAST. WRF-ARW AND NMM MODELS ALSO KEEP
SHOWERS WEST OF THE AREA INCREASING CONFIDENCE IN A DRY FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
CLOSED UPPER TROUGH WILL CONTINUE TRACKING EASTWARD TOWARDS THE
REGION OVERNIGHT. SURFACE WARM FRONT SHOULD BE NORTH OF THE CWA TO
START THE PERIOD...WITH THE MAIN COLD FRONT STILL MOVING EAST OF
THE MISSISSIPPI RIVER. THIS PUTS THE REGION IN THE WARM SECTOR OF
THE NEXT SYSTEM. LOW-LEVEL FLOW OVERNIGHT AND INTO FRIDAY WILL BE
OUT OF THE SOUTH TO SOUTHWEST...ALLOWING FOR AN INCREASE IN
MOISTURE. DO EXPECT THE EARLY PART OF TONIGHT TO BE DRY...THEN
SHOULD SEE AN INCREASE IN POPS FROM WEST TO EAST AFTER MIDNIGHT.
UPPER TROUGH MOVING THROUGH THE EASTERN CONUS ON FRIDAY WILL
DRIVE COLD FRONT TOWARD THE REGION THROUGH THE DAY. EXPECT MAINLY
SHOWERS EARLY IN THE DAY FRIDAY...WITH POTENTIAL FOR ISOLATED
THUNDERSTORMS IN THE AFTERNOON AS THE AIR MASS BECOMES WEAKLY TO
MODERATELY UNSTABLE. STRONGER CONVECTION MORE LIKELY WEST OF THE
REGION BACK IN NORTHWEST GEORGIA. DECREASING POPS THROUGH THE
NIGHT FRIDAY INTO SATURDAY MORNING AS FRONT MOVES THROUGH THE
AREA. DRY CONDITIONS ONCE AGAIN FOR SATURDAY. GUIDANCE TEMPERATURES
THROUGH THE PERIOD SEEM REASONABLE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE TO SETTLE INTO THE CWA FROM SATURDAY THROUGH
MONDAY. MOISTURE INCREASE MID WEEK AND ANOTHER FRONT POSSIBLY
MOVING SOUTH FROM THE NORTH MAY LEAD TO ISOLATED OR SCATTERED
AFTERNOON SHOWERS TUESDAY AND WEDNESDAY. TEMPERATURES SHOULD BE AT
OR ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
ONSHORE FLOW HAS ALLOWED A PLUME OF LOW LEVEL MOISTURE TO
MOVE INLAND. THE HIGHEST MOISTURE CONTENT IS LOCATED FROM THE
CENTRAL MIDLANDS INTO THE PEE DEE REGION...WITH CAE/CUB AND OGB AT
THE PERIPHERY. MODELS SUGGEST MVFR/IFR CIGS AT CAE/CUB AND
OGB...MIXING OUT SHORTLY AFTER SUNRISE. EXPECT SOUTH WINDS FROM 5
TO 10 KNOTS THROUGH THE REST OF THE MORNING. A COLD FRONT
APPROACHING FROM THE WEST AND A TIGHTENING PRESSURE GRADIENT WILL
CREATE GUSTY CONDITIONS TODAY. BUFKIT FORECAST SOUNDINGS INDICATE
THE POTENTIAL FOR GUSTS UP TO 20 KNOTS DURING THE AFTERNOON HOURS.
LATE THIS EVENING...MODELS SUPPORT SHOWERS DEVELOPING AHEAD OF
THE APPROACHING COLD FRONT. THESE SHOWERS MAY REACH THE CENTRAL
MIDLANDS AND CSRA TAF SITES NEAR THE END OF THE TAF
PERIOD...HOWEVER WILL KEEP OUT OF TAFS FOR THE TIME BEING DUE TO
TIMING UNCERTAINTY. LOW CIGS AHEAD OF THE COLD FRONT MAY ALSO
DEVELOP. THE SREF ENSEMBLE SUGGESTS THE POTENTIAL FOR MVFR CIGS
NEAR THE END OF THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE THURSDAY NIGHT
THROUGH EARLY SATURDAY AS A COLD FRONT CROSSES THE REGION.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
346 AM CDT THU APR 21 2016
.SHORT TERM...
FRONTAL ZONE EXTENDING ROUGHLY ALONG THE MISSISSIPPI VALLEY
APPEARS TO BE WEAKENING IN FAVOR OF BETTER UPPER DYNAMICS AND
SUPPORT FARTHER WEST IN NORTH TEXAS. THE LEADING FRONT MAY SERVE
AS A LOCAL FOCUS FOR CONVECTION WITH SOME HEATING BUT COMPLEX OF
STORMS MOVING ALONG THE COAST IN WHAT APPEARS TO BE A MINOR MCV
MAY IMPEDE INFLOW AS WELL AS PROVIDE THICK CANOPY OVER THE AREA
THIS MORNING. LATEST HRRR MODEL RUN DOES SHOW THIS SCENARIO WITH
ONLY MODEST COVERAGE OVER LAND AREAS AND MORE ROBUST CONVECTION
OVER THE NEAR SHORE WATERS. WILL INDICATE 50-60 PERCENT RAIN
CHANCES TODAY BUT MCV PROGRESSION WILL MAINTAIN UNCERTAINTY ON QPF
EXPECTATIONS. WPC HAS OUTLOOKED A SLIGHT RISK FOR FLASH FLOODING
THAT MAY POTENTIALLY MATERIALIZE LATER TODAY. BETTER FRONTAL
FORCING IS THEN EXPECTED OVERNIGHT INTO FRIDAY MORNING BUT ARE IN
CONSENSUS IN SHOWING SOME BRIEF STALLING ALONG THE COAST UNTIL THE
DENSER AIR MASS ARRIVES LATE FRIDAY INTO EAERLY SATURDAY. RAIN
CHANCES WILL BE MAINTAINED THROUGH FRIDAY NIGHT WITH CONSIDERABLE
IMPROVEMENT EXPECTED FOR THE WEEKEND. 24/RR
.LONG TERM...
SURFACE HIGH PRESSURE TO PROVIDE FAIR WEATHER THROUGH EARLY
MONDAY. A FRONTAL ZONE IN THE NORTHERN STATES WILL USHER A TROWAL
ALONG THE LOWER MISSISSIPPI VALLEY TO AID IN FOCUSING RAINFALL
ONCE AGAIN OVERNIGHT MONDAY. SUPPORT FOR CONVECTION WILL BE
LIMITED AND WANING UPON ARRIVAL AS HIGH PRESSURE BUILDS FROM THE
EAST TO BRING ABOVE NORMAL TEMPERATURES AND LOWER RAIN CHANCES
LATTER PART OF THE FORECAST PERIOD. 24/RR
&&
.AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL TODAY OUTSIDE OF SHOWERS AND
STORMS. A SYSTEM WILL BE MOVING INTO THE AREA BRINGING A CHANCE OF
SHOWERS AND THUNDERSTORMS TODAY. THE BEST CHANCE FOR RAIN WILL BE
THIS AFTERNOON ACROSS THE AREA. EXPECT THE RAIN CHANCES TO REMAIN
HIGH INTO THE EVENING AND OVERNIGHT HOURS. WILL HAVE TO MAKE SOME
CHANGES WITH THE NEXT ISSUANCE AND WILL HAVE MONITOR THE
SITUATION THROUGHOUT THE DAY. 13/MH
&&
.MARINE...
EXPECT GENERALLY LIGHT EAST TO SOUTHEAST WINDS. A COLD FRONT IS
STILL EXPECTED TO MOVE THROUGH THE COASTAL WATERS ON FRIDAY. EXPECT
OFFSHORE WINDS LATE FRIDAY AND SATURDAY BEFORE QUICKLY VEERING BACK
TO ONSHORE SUNDAY AS HIGH PRESSURE MOVES OVER THE EASTERN GULF AND
ALONG THE ATLANTIC COAST. 13/MH
&&
.DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...MINOR RIVER FLOODING.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 77 61 79 58 / 60 60 40 10
BTR 80 63 81 59 / 70 60 40 10
ASD 78 65 80 61 / 50 50 40 10
MSY 79 66 79 64 / 50 40 40 20
GPT 77 66 78 63 / 50 40 40 20
PQL 77 64 78 61 / 40 30 40 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
24/RR
13/MH
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1140 PM CDT WED APR 20 2016
.SYNOPSIS...
ISSUED AT 405 PM CDT WED APR 20 2016
H5 ANALYSIS THIS MORNING HAD A CLOSED LOW OVER NORTH PLATTE WITH
RIDGING OFF TO THE WEST OVER THE INTERMOUNTAIN WEST INTO THE
PANHANDLE OF IDAHO. EAST OF THE LOW...A LOW AMPLITUDE RIDGE OF
HIGH PRESSURE EXTENDS FROM THE FLORIDA PANHANDLE NORTH TO THE
OHIO VALLEY. HT FALLS THIS MORNING WERE MOST PRONOUNCED ACROSS
EASTERN KANSAS AND EASTERN NEBRASKA...WITH 70 METER FALLS NOTED AT
OMAHA AND 100 METER FALLS NOTED AT TOPEKA. CURRENT SATELLITE
IMAGERY HAS THE LOW NEAR LEXINGTON NEBRASKA WITH A SECONDARY
CIRCULATION NOTED AROUND OMAHA. SHOWERS HAVE CONTINUED TO ROTATE
AROUND THE NORTHERN AND WESTERN PERIPHERY OF THE LOW TODAY AND
HAVE MADE IT AS FAR WEST AS A MERRIMAN TO OGALLALA LINE. OVER THE
PAST COUPLE OF HOURS...SOME CONVECTIVE SHOWERS HAVE DEVELOPED OVER
SERN LINCOLN AND FRONTIER COUNTIES. ELSEWHERE...A MORE PERSISTENT
SHIELD OF RAIN WAS OCCURRING ACROSS THE NEBRASKA SANDHILLS.
HOURLY RAINFALL RATES WERE LIGHT...AT OR UNDER 3 HUNDREDTHS OF AN
INCH. TEMPERATURES AS OF 3 PM CDT RANGED FROM 51 TO 59 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 405 PM CDT WED APR 20 2016
THIS EVENING AND TONIGHT...EXPANDED HIGH CHC POPS WEST TO HWY 83
TO ACCOUNT FOR SCATTERED SHOWERS ROTATING AROUND THE LOW. ALSO
EXPANDED ISO THUNDER MENTION FOR SOUTHERN HALF OF THE FORECAST
AREA. FORECAST SOUNDINGS SHOW STEEP LOW LEVEL LAPSE RATES AND
PERIODS OF SIGNIFICANT LIFT. RAP ANALYSIS ALSO SHOWS MARGINAL
CAPE...GENERALLY 500 J/KG OR LESS...LIFTED INDEX AS LOW AS -1...
AND MID LEVEL LAPSE RATES NEAR 7C/KM. GIVEN DEEP COLD AIR
ALOFT...SMALL HAIL IS POSSIBLE WITH ANY STORM. HRRR AND RAP
INDICATE MOST OF THE SHOWER/STORM ACTIVITY OUTSIDE NORTH CENTRAL
NEBRASKA WILL BE DIURNALLY DRIVEN. SLOWLY PULL POPS FOR
BOYD...HOLT...WHEELER COUNTIES TONIGHT DUE TO THE PROXIMITY OF AN
AREA OF STEADY RAIN OVER NORTHEAST NEBRASKA. MADE LITTLE CHANGE TO
MIN TEMPS AS PREVIOUS FORECAST LOWS ARE SIMILAR TO 12Z MOS
GUIDANCE SUITE...COOLER PANHANDLE AND WEST FOR CLEARING SKY AND
LIGHT WINDS AND MILD NORTH CENTRAL FOR SUSTAINED CLOUDINESS.
DESPITE RECENT RAINFALL AND LIGHTENING WINDS OVERNIGHT...RISK OF
FOG IS LOW. SLIGHTLY DRIER AIR MOVES IN AS SHOWN BY FALLING MIXING
RATIOS...AND AS SURFACE WINDS TURN WESTERLY/NORTHWESTER...ITS NOT
AS FAVORABLE FOR FOG FORMATION.
THURSDAY...H5 LOW SCOOTS EAST INTO IOWA AND THE H3 JET MAX CENTERS
OVER THE MISSOURI RIVER. TRENDED MAX TEMPS TOWARD THE MAV...WHICH
RESULTED IN AN INCREASE OF A DEGREE OR SO AREAWIDE. NAM SOUNDINGS
INDICATE DRY AIR ALOFT...WEAK TO NON EXISTENT LIFT IN THE LOWER
LEVELS...AND A MIXED LAYER APPROACH 700HPA. MID LEVEL FGEN FORCING
ALSO WEAKENS AS THE LOW MOVES EAST OF THE AREA. WITH MAINLY FAIR
CONDITIONS AND UNINHIBITED MIXING...BREEZY NORTH WINDS ARE LIKELY
AND H85 TEMPS AROUND 10C SHOULD TRANSLATE TO HIGHS NEAR 70F.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 405 PM CDT WED APR 20 2016
MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE MID RANGE...A
BENIGN WEATHER PATTERN IS EXPECTED IN THE MID RANGE WITH
TEMPERATURES BEING THE MAIN FORECASTING CHALLENGE. THE CLOSED LOW
WILL TRACK INTO THE OHIO VALLEY THURSDAY NIGHT INTO FRIDAY...WHILE
RIDGING ALOFT BUILDS EAST FROM THE CENTRAL ROCKIES INTO THE
CENTRAL PLAINS. TEMPERATURES FRIDAY WILL REACH THE LOWER TO MIDDLE
70S...FOLLOWED BY MID 70S TO AROUND 80 FOR SATURDAY. THE LATEST
NAM SOLN WAS BEGINNING TO INDICATE A FAVORABLE ENVIRONMENT FOR
THUNDERSTORMS SATURDAY AFTERNOON IN THE WEST WITH VERY FAVORABLE
SURFACE BASED INSTABILITY AND A DECENT AMOUNT OF SD CAPE.
HOWEVER...SHEAR LOOKS WEAK ATTM. THE GFS AND ECMWF SOLNS HOLD OFF
ON CONVECTION UNTIL SAT EVENING AND HAVE OPTED TO GO THIS ROUTE
AND LEAVE SAT AFTERNOON DRY FOR NOW. BETTER CHANCES FOR
PRECIPITATION WILL ARRIVE IN THE WEST SATURDAY EVENING AS A LEAD
SHORTWAVE CROSSES THE PANHANDLE.
LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...BEGINNING SATURDAY
NIGHT...CHANCES FOR PCPN WILL INCREASE IN THE WEST AS A LEAD
SHORTWAVE CROSSES THE PANHANDLE. THIS WILL BE FOLLOWED BY A CLOSED
LOW WHICH TRACKS ACROSS SRN SD SUNDAY INTO SUNDAY NIGHT. WRAP
AROUND PCPN FROM THE SYSTEM WILL IMPACT THE NORTHERN CWA ON
SUNDAY AND SUNDAY NIGHT. FURTHER SOUTH...COOLER AND WINDY CONDS
ARE EXPECTED SUNDAY...WITH NOT MUCH IN THE WAY OF PCPN EXPECTED.
BETTER CHANCES FOR PRECIPITATION WILL ARRIVE MONDAY NIGHT INTO
WEDNESDAY AS A SECOND UPPER LOW LEVEL LOW TRACKS FROM THE CENTRAL
ROCKIES ONTO THE CENTRAL PLAINS. TEMPERATURES WILL BE MUCH COOLER
AS WELL WITH HIGHS IN THE 50S BY MIDWEEK NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1140 PM CDT WED APR 20 2016
VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH THURSDAY EVENING.
LOW PRESSURE WILL DRIFT INTO THE MIDWEST THURSDAY WITH DRIER MORE
STABLE AIR MOVING INTO WESTERN AND NORTH CENTRAL NEBRASKA.
&&
.HYDROLOGY...
ISSUED AT 405 PM CDT WED APR 20 2016
RISES EXPECTED TO CONTINUE ON THE SOUTH PLATTE RIVER FOR THE NEXT
SEVERAL DAYS DUE TO RECENT PRECIPITATION OVER WESTERN NEBRASKA
AND COLORADO. USGS STREAM GAUGE AT ATWOOD CO HAS SHOWN A LEVELING
OFF WHILE JULESBURG STILL SHOWS A STEADY RISE. IN COORDINATION
WITH THE MBRFC...A FORECAST SHOWS A CREST AROUND 7 FEET LATE
FRIDAY AT ROSCOE...WHICH PUTS IT AT ACTION STAGE. NO FLOODING IS
EXPECTED AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...CDC
HYDROLOGY...BUTTLER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
242 AM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE AND AN ACCOMPANYING FRONTAL SYSTEM WILL MOVE EAST
ACROSS THE OHIO VALLEY TOWARD THE REGION TODAY. RAIN LATER TODAY
INTO FRIDAY WILL BE FOLLOWED BY MILD AND DRY WEATHER THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
20 DEWPOINTS THE BIG STORY AND ANY RAIN APPROACHING FROM THE WEST
WILL HAVE TO DO QUITE A BIT OF MOISTENING TO THE LOWER ATMOSPHERE
BEFORE IT WOULD REACH THE GROUND. HAVE DELAYED THE ONSET OF SHRA
IN THE WEST TO VERY LATE MORNING AND EARLY AFTN IN LINE WITH THE
CONCEPTUAL/HUMAN MODEL...AND THE LATEST HRRR AND RAP. TEMPS MAY
DIP INTO THE 30S IN THE EASTERN VALLEYS WHERE THERE IS LESS WIND.
MOST OTHER PLACES WILL SEE TEMPS STAY MILD THRU SUNRISE. WE
SHOULD ALSO TEMPS RISE INTO THE U60S-L70S.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
MODELS IN REASONABLY GOOD AGREEMENT SHOWING TWO WAVES OF SHOWERS
THURSDAY AND FRIDAY AS A LONG WAVE TROUGH MOVES EAST FROM
THE MIDWEST TOWARD THE MID-ATLANTIC. THE FIRST WAVE OF SHOWERS
WILL BE ASSOCIATED WITH SOME ISENTROPIC LIFT AHEAD OF A WEAK
SURFACE WAVE TRACKING NORTHEAST UP THE SAINT LAWRENCE VALLEY
THURSDAY INTO THURSDAY EVENING WITH A SURFACE TROUGH EXTENDING
SOUTH ACROSS PENNSYLVANIA. OVERALL FORCING WITH THIS FIRST WAVE
WILL NOT BE VERY IMPRESSIVE BUT SHOULD BE ENOUGH TO TRIGGER A FEW
SHOWERS DURING THE DAY THURSDAY MOVING FROM WEST TO EAST. BEST
CHANCE OF SHOWERS WILL BE OVER THE NORTHWESTERN PART OF PA CLOSEST
TO THE BEST DYNAMICAL FORCING. POPS WILL BE LOWER FARTHER SOUTH
AND EAST TOWARD THE SUSQUEHANNA VALLEY.
BETTER CHANCE FOR SHOWERS WILL BE FRIDAY AS THE MAIN MID-LEVEL LOW
PRESSURE AREA APPROACHES FROM THE MIDWEST. INTERESTING FACTOR
WITH THIS SYSTEM WILL BE THE POTENTIAL FOR SOME MODEST
INSTABILITY TO DEVELOP AHEAD OF THE ASSOCIATED COLD FRONT FRIDAY
AFTERNOON... WHICH COULD RESULT IN SCATTERED THUNDERSTORMS ALONG
WITH THE SHOWERS. AT THIS POINT ANY INSTABILITY LOOKS TO BE SMALL
ENOUGH TO KEEP THE SEVERE RISK VERY LOW. LATEST SPC OUTLOOK
CONFIRMS THIS THINKING WITH PA IN A GENERAL THUNDER OUTLOOK BUT
NO SEVERE RISK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DRY WEATHER WILL RETURN BEHIND THE COLD FRONT FRIDAY NIGHT. AT THIS
POINT THE WEEKEND LOOKS TO BE DRY WITH SEASONABLY MILD
TEMPERATURES AS HIGH PRESSURE MOVES FROM THE MID-WEST OVER THE
MID- ATLANTIC. NEXT WEATHER SYSTEM WILL APPROACH FROM THE MIDWEST
EARLY NEXT WEEK WITH A CHANCE OF SHOWERS INCREASING MONDAY
THROUGH TUESDAY. TEMPERATURES WILL TREND COOLER BY TUESDAY AS A
DEVELOPING GREENLAND BLOCK FORCES UPPER LEVEL LOW PRESSURE OVER
QUEBEC WHICH WILL DRIVE A COOL AIRMASS SOUTHEAST FROM CANADA
TOWARD THE NORTHEAST U.S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE AND ASSOC DRY AIR MASS OVER THE REGION WILL ENSURE
VFR CONDS AND LIGHT WINDS FOR THE BALANCE OF THE NIGHT. AN
APPROACHING COLD FRONT WILL SPREAD SCT SHOWERS INTO THE WESTERN
HALF OF PA LATE THIS MORNING THRU THIS EVENING. ALTHOUGH
WIDESPREAD VFR CONDS WILL PREVAIL...BRIEF REDUCTIONS ARE POSSIBLE
IN PASSING SHOWERS FROM KAOO TO KIPT AND POINTS NWRD.
OUTLOOK...
FRI...SCT PM TSRA IMPACTS POSSIBLE.
SAT...EARLY AM LOW CIGS POSSIBLE W MTNS.
SUN...NO SIG WX EXPECTED.
MON...PM SHRA/REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
150 AM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE AND AN ACCOMPANYING FRONTAL SYSTEM WILL MOVE EAST
ACROSS THE OHIO VALLEY TOWARD THE REGION TODAY. RAIN LATER TODAY
INTO FRIDAY WILL BE FOLLOWED BY MILD AND DRY WEATHER THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
20 DEWPOINTS THE BIG STORY AND ANY RAIN APPROACHING FROM THE WEST
WILL HAVE TO DO QUITE A BIT OF MOISTENING TO THE LOWER ATMOSPHERE
BEFORE IT WOULD REACH THE GROUND. HAVE DELAYED THE ONSET OF SHRA
IN THE WEST TO VERY LATE MORNING AND EARLY AFTN IN LINE WITH THE
CONCEPTUAL/HUMAN MODEL...AND THE LATEST HRRR AND RAP. TEMPS MAY
DIP INTO THE 30S IN THE EASTERN VALLEYS WHERE THERE IS LESS WIND.
MOST OTHER PLACES WILL SEE TEMPS STAY MILD THRU SUNRISE. WE
SHOULD ALSO TEMPS RISE INTO THE U60S-L70S.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
MODELS IN REASONABLY GOOD AGREEMENT SHOWING TWO WAVES OF SHOWERS
THURSDAY AND FRIDAY AS A LONG WAVE TROUGH MOVES EAST FROM
THE MIDWEST TOWARD THE MID-ATLANTIC. THE FIRST WAVE OF SHOWERS
WILL BE ASSOCIATED WITH SOME ISENTROPIC LIFT AHEAD OF A WEAK
SURFACE WAVE TRACKING NORTHEAST UP THE SAINT LAWRENCE VALLEY
THURSDAY INTO THURSDAY EVENING WITH A SURFACE TROUGH EXTENDING
SOUTH ACROSS PENNSYLVANIA. OVERALL FORCING WITH THIS FIRST WAVE
WILL NOT BE VERY IMPRESSIVE BUT SHOULD BE ENOUGH TO TRIGGER A FEW
SHOWERS DURING THE DAY THURSDAY MOVING FROM WEST TO EAST. BEST
CHANCE OF SHOWERS WILL BE OVER THE NORTHWESTERN PART OF PA CLOSEST
TO THE BEST DYNAMICAL FORCING. POPS WILL BE LOWER FARTHER SOUTH
AND EAST TOWARD THE SUSQUEHANNA VALLEY.
BETTER CHANCE FOR SHOWERS WILL BE FRIDAY AS THE MAIN MID-LEVEL LOW
PRESSURE AREA APPROACHES FROM THE MIDWEST. INTERESTING FACTOR
WITH THIS SYSTEM WILL BE THE POTENTIAL FOR SOME MODEST
INSTABILITY TO DEVELOP AHEAD OF THE ASSOCIATED COLD FRONT FRIDAY
AFTERNOON... WHICH COULD RESULT IN SCATTERED THUNDERSTORMS ALONG
WITH THE SHOWERS. AT THIS POINT ANY INSTABILITY LOOKS TO BE SMALL
ENOUGH TO KEEP THE SEVERE RISK VERY LOW. LATEST SPC OUTLOOK
CONFIRMS THIS THINKING WITH PA IN A GENERAL THUNDER OUTLOOK BUT
NO SEVERE RISK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DRY WEATHER WILL RETURN BEHIND THE COLD FRONT FRIDAY NIGHT. AT THIS
POINT THE WEEKEND LOOKS TO BE DRY WITH SEASONABLY MILD
TEMPERATURES AS HIGH PRESSURE MOVES FROM THE MID-WEST OVER THE
MID- ATLANTIC. NEXT WEATHER SYSTEM WILL APPROACH FROM THE MIDWEST
EARLY NEXT WEEK WITH A CHANCE OF SHOWERS INCREASING MONDAY
THROUGH TUESDAY. TEMPERATURES WILL TREND COOLER BY TUESDAY AS A
DEVELOPING GREENLAND BLOCK FORCES UPPER LEVEL LOW PRESSURE OVER
QUEBEC WHICH WILL DRIVE A COOL AIRMASS SOUTHEAST FROM CANADA
TOWARD THE NORTHEAST U.S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
UPDATED AT 03Z... VFR WITH CLEAR SKIES THROUGH THIS EVENING.
INCREASING MID AND HIGH CLOUDS LATE TONIGHT THROUGH THURSDAY
MORNING WITH CIGS AOA 10 KFT. SCATTERED SHOWERS DEVELOPING
THURSDAY AFTERNOON MAINLY AT BFD/JST/AOO/UNV WITH LOCALIZED MVFR
CONDITIONS POSSIBLE. HAVE INCREASED CIGS TO BROKEN BUT LEFT THEM
VFR THROUGH 00Z.
OUTLOOK...
THU NGT - FRI...SHRA/RESTRICTIONS POSSIBLE.
SAT-SUN...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...CERU/MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
321 AM EDT THU APR 21 2016
.SYNOPSIS...
PRECIPITATION CHANCES INCREASE THRU FRIDAY AS A SECOND COLD FRONT
MOVES IN FROM THE WEST...ALTHOUGH RAINFALL AMOUNTS ARE EXPECTED
TO REMAIN LIGHT. FOLLOWING THE FRONTAL PASSAGE ON SATURDAY...DRY
AND WARM HIGH PRESSURE WILL BUILD IN ACROSS THE FORECAST AREA FOR
SUNDAY. THE HIGH WILL SLIDE OFFSHORE EARLY MONDAY IN ADVANCE OF
ANOTHER WEAK FRONT AND CHANCE FOR LIGHT PRECIPITATION TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM...A SHALLOW WEDGE OF HIGH PRESSURE PERSISTS OVER MOST
OF THE AREA...THE HIGH BEING CENTERED OFF THE MID-ATLANTIC COAST
AND DRIFTING SOUTH. AN AREA OF LOW STRATUS WILL PERSIST THRU THE
MORNING OVER THE ERN HALF OF THE CWFA AS MOIST LOW LEVEL FLOW
OCCURS OVER THE WEDGE.
AFTER DAYBREAK...AS THE HIGH BECOMES CENTERED OFF THE OUTER
BANKS...THE FLOW WILL VEER AND THE LOW LEVEL THERMAL GRADIENT
WILL WEAKEN. THIS WILL ALLOW THE STRATUS TO DISSOLVE. SKIES
TODAY ARE EXPECTED TO BE PARTLY TO MOSTLY SUNNY WITH MAINLY
PATCHY CIRRUS. MEANWHILE...LOW PRESSURE WILL MOVE EWD THRU THE
MISSISSIPPI VALLEY. THE ASSOCIATED UPPER TROUGH WILL BEGIN TO
DISPLACE THE INCUMBENT RIDGE OVER OUR AREA LATE IN THE DAY. AT
THAT TIME PREFRONTAL WAA WILL BEGIN TO INCREASE OVER THE MTNS. WITH
TEMPS WARMING A CATEGORY OR SO ABOVE NORMAL...AND WITH LAPSE RATES
BECOMING A BIT MORE FAVORABLE...A FEW SHOWERS OR LOW-TOPPED TSTMS
ARE POSSIBLE MAINLY OVER SW NC.
GFS AND NAM QPF SUGGEST THERE MAY BE A ROUND OF LIGHT PRECIP
ASSOCIATED WITH WARM CONVEYOR BELT THAT PROGRESSES ACRS THE AREA
DURING THE FIRST HALF OF THE NIGHT...FOLLOWED BY ANOTHER ROUND
PRECIP INVOF THE COLD FRONT FRIDAY MRNG. ISENTROPIC LIFT IS
SOMEWHAT MURKY WITH THAT FEATURE...SO I EFFECTIVELY ADVERTISE A
GRADUAL INCREASE FROM W TO E...AS MOISTURE DEEPENS AND SHORTWAVE
APPROACHES. WITH INCREASING CLOUDS AND BREEZY CONDITIONS TONIGHT...I
FAVORED THE WARMER TEMP GUIDANCE. MINS WILL BE NEAR 10 DEGREES
ABOVE NORMAL.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 210 AM THURSDAY...AN UPPER LOW AND ITS ASSOCIATED TROUGH MOVE
INTO THE AREA FRIDAY AND ACROSS THE AREA FRIDAY NIGHT. THE
ASSOCIATED COLD FRONT MOVES INTO THE AREA FROM THE WEST FRIDAY THEN
ACROSS AND EAST OF THE AREA FRIDAY NIGHT. LOW LEVEL AND MID LEVEL
FORCING...ALONG WITH UPPER DIVERGENCE...INCREASE ENOUGH TO WARRANT
THE CONTINUED LIKELY POP FOR FRIDAY. INSTABILITY DEVELOPS AS WELL
KEEPING THE POTENTIAL FOR THUNDERSTORMS OVER THE AREA. HOWEVER...
THE INSTABILITY REMAINS WEAK WITH EVEN THE MUCAPE BELOW 1000 J/KG.
GUIDANCE HAS BACKED OFF ON THE INCREASING SHEAR KEEPING IT WEAK OVER
OUR AREA...WITH BETTER SHEAR NORTH AND SOUTH OF THE CWFA. STILL...
GIVEN THE COMBINATION OF FORCING AND INSTABILITY AND FAVORABLE
TIMING...AN ISOLATED SEVERE STORM CANNOT BE RULED OUT...BUT THE
CHANCE REMAINS VERY LOW. CHANCE OF EXCESSIVE QPF REMAINS QUITE LOW
AS WELL. GIVEN THE RECENT DRY CONDITIONS...MODERATE RAINFALL WOULD
BE VERY WELCOME. PRECIP TAPERS OFF FRIDAY NIGHT AS THE FRONT MOVES
EAST OF THE AREA. HIGHS WILL BE A FEW DEGREES ABOVE NORMAL WITH LOWS
5 TO 10 DEGREES ABOVE.
DRY CONDITIONS AND CLEARING SKIES RETURN SATURDAY AS HIGH PRESSURE
BUILDS BACK INTO THE AREA. HIGHS WILL BE AROUND 5 DEGREES ABOVE
NORMAL WITH LOWS 5 TO 10 DEGREES ABOVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...A PROGRESSIVE PATTERN SETS UP FOR THE MEDIUM
RANGE. UPPER RIDGE AXIS CROSSES THE AREA SUNDAY...WITH WEAK SHORT
WAVE ENERGY MOVING THROUGH MONDAY. FLOW REMAINS ZONAL OVER THE AREA
TUESDAY AS A SHORT WAVE PASSES BY TO OUR NORTH...WITH YET ANOTHER
RIDGE AXIS MOVING THROUGH ON WEDNESDAY. AT THE SURFACE...HIGH
PRESSURE OVER THE AREA SUNDAY SLIDES EAST MONDAY WITH SOUTH TO
SOUTHWESTERLY FLOW DEVELOPING. THE GFS SHOWS SOME SHOWERS DEVELOPING
ACROSS THE MOUNTAINS MONDAY...BUT KEPT THE FORECAST DRY IN LINE WITH
THE ECMWF AND CANADIAN. THE TUESDAY SHORT WAVE MOVES A SURFACE LOW
ACROSS THE MID-ATLANTIC WHICH DRAGS A COLD FRONT SOUTH TOWARD OUR
AREA. THE GFS MOVES THE FRONT INTO OUR AREA FASTER THAN THE ECMWF
AND CANADIAN. THE ECMWF DOES MOVE THE FRONT INTO THE AREA WEDNESDAY
WHILE THE GFS STALLS THE FRONT ACROSS THE CAROLINAS. FOLLOWING A
GUIDANCE BLEND BRINGS CHANCE POP INTO THE MOUNTAINS AND I-40
CORRIDOR TUESDAY...THEN ACROSS THE ENTIRE CWFA WEDNESDAY.
HIGHS RISE THROUGH THE PERIOD...REACHING THE MID 80S OUTSIDE OF THE
MTNS TUESDAY...AND AROUND 80 IN THE MOUNTAIN VALLEYS. HIGHS FALL A
FEW DEGREES ON WEDNESDAY. LOWS FOLLOW A SIMILAR TREND...RISING INTO
THE LOW 60S OUTSIDE OF THE MOUNTAINS AND MID 50S MOUNTAIN VALLEYS.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
AT KCLT/KHKY...ATLANTIC MOISTURE FLOWING OVER SHALLOW WEDGE OF HIGH
PRESSURE IS ALREADY PRODUCING MVFR CIGS OVER THE NC PIEDMONT. THE
NAM FAMILY OF MODELS IS HANDLING THE STRATUS MOST ACCURATELY
ATTM...SO USED A CONSENSUS OF NAM AND HRRR FOR CLOUD BASES THRU
THE MRNG. THEY GENERALLY SHOW AT LEAST BKN MVFR PERSISTING UNTIL A
COUPLE HRS AFTER DAYBREAK...AND HINT AT PATCHY IFR AS WELL. WITH
CIGS ALREADY DEVELOPING AND WITH DRY SFC DEWPOINTS...NOT SURE IF
SATURATION WILL OCCUR LOW ENOUGH TO BRING CIGS TO IFR...SO THAT IS
LEFT IN TEMPO. FOLLOWING THE DISSOLUTION OF THE STRATUS...MAINLY
MID-HIGH CLOUDS WILL BE SEEN TODAY. APPROACH OF COLD FRONT FROM THE
WEST TONIGHT WILL REINTRODUCE A LOW VFR DECK THIS EVENING. WINDS
WILL REMAIN SOUTHERLY...AND A FEW LOW-END GUSTS ARE POSSIBLE
THIS AFTN.
ELSEWHERE...MOST GUIDANCE KEEPS THE IFR CIGS EAST OF THE REMAINING
TAF SITES...BUT MVFR SHOULD EXPAND OVER KGSP/KGMU/KAVL BEFORE
DAWN. CAN/T TOTALLY RULE OUT IFR...SO I WILL KEEP AN EYE ON NEARBY
TRENDS AND AMD IF NECESSARY. THIS WILL BE THE MAIN IMPACTFUL WEATHER
THRU THE DAY TODAY...WITH SCT-BKN CIRRUS AND MODEST SOUTHERLY
WINDS. A SMALL CHC OF TSRA EXISTS OVER THE SW NC MTNS...BUT CHC
IS TOO LOW TO MENTION AT KAVL. COLD FRONT WILL BRING BETTER SHRA
CHANCES THIS EVENING FROM WEST TO EAST...HENCE PROB30 AT KAVL. MVFR
CIGS WILL PRECEDE THE FRONT...BUT ONLY KAND IS EXPECTED TO SEE
SUCH PRIOR TO 06Z.
OUTLOOK...RAIN CHANCES INCREASE EARLY FRI AHEAD OF ANOTHER COLD
FRONT APPROACHING THE AREA. HIGH PRESSURE AND MOSTLY VFR CONDITIONS
WILL RETURN SATURDAY FOLLOWING THE DEPARTURE OF THE FRONT.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-06Z
KCLT HIGH 96% HIGH 92% HIGH 100% HIGH 100%
KGSP HIGH 90% HIGH 92% HIGH 100% HIGH 100%
KAVL HIGH 85% HIGH 92% HIGH 100% MED 78%
KHKY HIGH 91% HIGH 89% HIGH 100% HIGH 100%
KGMU HIGH 98% HIGH 98% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 91% HIGH 100% HIGH 88%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...WIMBERLEY
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
314 AM EDT THU APR 21 2016
.SYNOPSIS...
PRECIPITATION CHANCES INCREASE THRU FRIDAY AS A SECOND COLD FRONT
MOVES IN FROM THE WEST...ALTHOUGH RAINFALL AMOUNTS ARE EXPECTED
TO REMAIN LIGHT. FOLLOWING THE FRONTAL PASSAGE ON SATURDAY...DRY
AND WARM HIGH PRESSURE WILL BUILD IN ACROSS THE FORECAST AREA FOR
SUNDAY. THE HIGH WILL SLIDE OFFSHORE EARLY MONDAY IN ADVANCE OF
ANOTHER WEAK FRONT AND CHANCE FOR LIGHT PRECIPITATION TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM...A SHALLOW WEDGE OF HIGH PRESSURE PERSISTS OVER MOST
OF THE AREA...THE HIGH BEING CENTERED OFF THE MID-ATLANTIC COAST
AND DRIFTING SOUTH. AN AREA OF LOW STRATUS WILL PERSIST THRU THE
MORNING OVER THE ERN HALF OF THE CWFA AS MOIST LOW LEVEL FLOW
OCCURS OVER THE WEDGE.
AFTER DAYBREAK...AS THE HIGH BECOMES CENTERED OFF THE OUTER
BANKS...THE FLOW WILL VEER AND THE LOW LEVEL THERMAL GRADIENT
WILL WEAKEN. THIS WILL ALLOW THE STRATUS TO DISSOLVE. SKIES
TODAY ARE EXPECTED TO BE PARTLY TO MOSTLY SUNNY WITH MAINLY
PATCHY CIRRUS. MEANWHILE...LOW PRESSURE WILL MOVE EWD THRU THE
MISSISSIPPI VALLEY. THE ASSOCIATED UPPER TROUGH WILL BEGIN TO
DISPLACE THE INCUMBENT RIDGE OVER OUR AREA LATE IN THE DAY. AT
THAT TIME PREFRONTAL WAA WILL BEGIN TO INCREASE OVER THE MTNS. WITH
TEMPS WARMING A CATEGORY OR SO ABOVE NORMAL...AND WITH LAPSE RATES
BECOMING A BIT MORE FAVORABLE...A FEW SHOWERS OR LOW-TOPPED TSTMS
ARE POSSIBLE MAINLY OVER SW NC.
GFS AND NAM QPF SUGGEST THERE MAY BE A ROUND OF LIGHT PRECIP
ASSOCIATED WITH WARM CONVEYOR BELT THAT PROGRESSES ACRS THE AREA
DURING THE FIRST HALF OF THE NIGHT...FOLLOWED BY ANOTHER ROUND
PRECIP INVOF THE COLD FRONT FRIDAY MRNG. IN LIGHT OF SOMEWHAT MURKY
ISENTROPIC LIFT...I WILL ADVERTISE A GENERAL INCREASE THRU THE NIGHT
FROM W TO E...AS MOISTURE DEEPENS AND SHORTWAVE APPROACHES. WITH
INCREASING CLOUDS AND BREEZY CONDITIONS TONIGHT...I FAVORED THE
WARMER TEMP GUIDANCE. MINS WILL BE NEAR 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 210 AM THURSDAY...AN UPPER LOW AND ITS ASSOCIATED TROUGH MOVE
INTO THE AREA FRIDAY AND ACROSS THE AREA FRIDAY NIGHT. THE
ASSOCIATED COLD FRONT MOVES INTO THE AREA FROM THE WEST FRIDAY THEN
ACROSS AND EAST OF THE AREA FRIDAY NIGHT. LOW LEVEL AND MID LEVEL
FORCING...ALONG WITH UPPER DIVERGENCE...INCREASE ENOUGH TO WARRANT
THE CONTINUED LIKELY POP FOR FRIDAY. INSTABILITY DEVELOPS AS WELL
KEEPING THE POTENTIAL FOR THUNDERSTORMS OVER THE AREA. HOWEVER...
THE INSTABILITY REMAINS WEAK WITH EVEN THE MUCAPE BELOW 1000 J/KG.
GUIDANCE HAS BACKED OFF ON THE INCREASING SHEAR KEEPING IT WEAK OVER
OUR AREA...WITH BETTER SHEAR NORTH AND SOUTH OF THE CWFA. STILL...
GIVEN THE COMBINATION OF FORCING AND INSTABILITY AND FAVORABLE
TIMING...AN ISOLATED SEVERE STORM CANNOT BE RULED OUT...BUT THE
CHANCE REMAINS VERY LOW. CHANCE OF EXCESSIVE QPF REMAINS QUITE LOW
AS WELL. GIVEN THE RECENT DRY CONDITIONS...MODERATE RAINFALL WOULD
BE VERY WELCOME. PRECIP TAPERS OFF FRIDAY NIGHT AS THE FRONT MOVES
EAST OF THE AREA. HIGHS WILL BE A FEW DEGREES ABOVE NORMAL WITH LOWS
5 TO 10 DEGREES ABOVE.
DRY CONDITIONS AND CLEARING SKIES RETURN SATURDAY AS HIGH PRESSURE
BUILDS BACK INTO THE AREA. HIGHS WILL BE AROUND 5 DEGREES ABOVE
NORMAL WITH LOWS 5 TO 10 DEGREES ABOVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...A PROGRESSIVE PATTERN SETS UP FOR THE MEDIUM
RANGE. UPPER RIDGE AXIS CROSSES THE AREA SUNDAY...WITH WEAK SHORT
WAVE ENERGY MOVING THROUGH MONDAY. FLOW REMAINS ZONAL OVER THE AREA
TUESDAY AS A SHORT WAVE PASSES BY TO OUR NORTH...WITH YET ANOTHER
RIDGE AXIS MOVING THROUGH ON WEDNESDAY. AT THE SURFACE...HIGH
PRESSURE OVER THE AREA SUNDAY SLIDES EAST MONDAY WITH SOUTH TO
SOUTHWESTERLY FLOW DEVELOPING. THE GFS SHOWS SOME SHOWERS DEVELOPING
ACROSS THE MOUNTAINS MONDAY...BUT KEPT THE FORECAST DRY IN LINE WITH
THE ECMWF AND CANADIAN. THE TUESDAY SHORT WAVE MOVES A SURFACE LOW
ACROSS THE MID-ATLANTIC WHICH DRAGS A COLD FRONT SOUTH TOWARD OUR
AREA. THE GFS MOVES THE FRONT INTO OUR AREA FASTER THAN THE ECMWF
AND CANADIAN. THE ECMWF DOES MOVE THE FRONT INTO THE AREA WEDNESDAY
WHILE THE GFS STALLS THE FRONT ACROSS THE CAROLINAS. FOLLOWING A
GUIDANCE BLEND BRINGS CHANCE POP INTO THE MOUNTAINS AND I-40
CORRIDOR TUESDAY...THEN ACROSS THE ENTIRE CWFA WEDNESDAY.
HIGHS RISE THROUGH THE PERIOD...REACHING THE MID 80S OUTSIDE OF THE
MTNS TUESDAY...AND AROUND 80 IN THE MOUNTAIN VALLEYS. HIGHS FALL A
FEW DEGREES ON WEDNESDAY. LOWS FOLLOW A SIMILAR TREND...RISING INTO
THE LOW 60S OUTSIDE OF THE MOUNTAINS AND MID 50S MOUNTAIN VALLEYS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
AT KCLT/KHKY...ATLANTIC MOISTURE FLOWING OVER SHALLOW WEDGE OF HIGH
PRESSURE IS ALREADY PRODUCING MVFR CIGS OVER THE NC PIEDMONT. THE
NAM FAMILY OF MODELS IS HANDLING THE STRATUS MOST ACCURATELY
ATTM...SO USED A CONSENSUS OF NAM AND HRRR FOR CLOUD BASES THRU
THE MRNG. THEY GENERALLY SHOW AT LEAST BKN MVFR PERSISTING UNTIL A
COUPLE HRS AFTER DAYBREAK...AND HINT AT PATCHY IFR AS WELL. WITH
CIGS ALREADY DEVELOPING AND WITH DRY SFC DEWPOINTS...NOT SURE IF
SATURATION WILL OCCUR LOW ENOUGH TO BRING CIGS TO IFR...SO THAT IS
LEFT IN TEMPO. FOLLOWING THE DISSOLUTION OF THE STRATUS...MAINLY
MID-HIGH CLOUDS WILL BE SEEN TODAY. APPROACH OF COLD FRONT FROM THE
WEST TONIGHT WILL REINTRODUCE A LOW VFR DECK THIS EVENING. WINDS
WILL REMAIN SOUTHERLY...AND A FEW LOW-END GUSTS ARE POSSIBLE
THIS AFTN.
ELSEWHERE...MOST GUIDANCE KEEPS THE IFR CIGS EAST OF THE REMAINING
TAF SITES...BUT MVFR SHOULD EXPAND OVER KGSP/KGMU/KAVL BEFORE
DAWN. CAN/T TOTALLY RULE OUT IFR...SO I WILL KEEP AN EYE ON NEARBY
TRENDS AND AMD IF NECESSARY. THIS WILL BE THE MAIN IMPACTFUL WEATHER
THRU THE DAY TODAY...WITH SCT-BKN CIRRUS AND MODEST SOUTHERLY
WINDS. A SMALL CHC OF TSRA EXISTS OVER THE SW NC MTNS...BUT CHC
IS TOO LOW TO MENTION AT KAVL. COLD FRONT WILL BRING BETTER SHRA
CHANCES THIS EVENING FROM WEST TO EAST...HENCE PROB30 AT KAVL. MVFR
CIGS WILL PRECEDE THE FRONT...BUT ONLY KAND IS EXPECTED TO SEE
SUCH PRIOR TO 06Z.
OUTLOOK...RAIN CHANCES INCREASE EARLY FRI AHEAD OF ANOTHER COLD
FRONT APPROACHING THE AREA. HIGH PRESSURE AND MOSTLY VFR CONDITIONS
WILL RETURN SATURDAY FOLLOWING THE DEPARTURE OF THE FRONT.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-06Z
KCLT HIGH 96% HIGH 92% HIGH 100% HIGH 100%
KGSP HIGH 90% HIGH 92% HIGH 100% HIGH 100%
KAVL HIGH 85% HIGH 92% HIGH 100% MED 78%
KHKY HIGH 91% HIGH 89% HIGH 100% HIGH 100%
KGMU HIGH 98% HIGH 98% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 91% HIGH 100% HIGH 88%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...WIMBERLEY
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
159 AM EDT THU APR 21 2016
.SYNOPSIS...
PRECIPITATION CHANCES INCREASE THROUGH FRIDAY AS A SECOND COLD
FRONT MOVES IN FROM THE WEST...ALTHOUGH RAINFALL AMOUNTS ARE
EXPECTED TO REMAIN LIGHT. FOLLOWING THE FRONTAL PASSAGE ON
SATURDAY...DRY AND WARM HIGH PRESSURE WILL BUILD IN ACROSS THE
FORECAST AREA FOR SUNDAY. THE HIGH WILL SLIDE OFFSHORE EARLY
MONDAY IN ADVANCE OF ANOTHER WEAK FRONT AND CHANCE FOR LIGHT
PRECIPITATION FROM MONDAY EVENING THROUGH WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 145 AM...STRATUS ARE BEGINNING TO DEVELOP EAST OF HWY 321
AS ATLANTIC MOISTURE FLOWS OVER WEAKENING WEDGE. BEST GUIDANCE
CONSENSUS SUGGESTS THESE CLOUDS WILL HAVE TROUBLE EXPANDING TO THE
BLUE RIDGE...BUT MAY CONTINUE TO EXPAND OVER ERN UPSTATE SC. SOME
LIGHT FOG MAY DEVELOP AS WELL...BUT DEWPT DEPRESSIONS ARE GENERALLY
TOO LARGE TO EXPECT SIGNIFICANT VSBY RESTRICTIONS. UPDATED TEMPS
ARE SOMEWHAT WARMER ON ACCOUNT OF THE STRATUS.
MODELS WILL ERODE WEDGE THROUGH THE EVENING/OVERNIGHT
HOURS...ALLOWING SFC FLOW OVER THE PIEDMONT TO GRADUALLY VEER
AS WEAK MOISTURE ADVECTION COMMENCES. HOWEVER IT IS NOT UNTIL
MIDDAY THAT UPGLIDE/UPSLOPE WILL BE CAPABLE OF PRECIP...THOUGH
LITTLE FURTHER ENHANCEMENT OCCURS DURING THE DAY. GUIDANCE FAVORS
SHRA POTENTIAL LATE IN THE PERIOD ACROSS THE WESTERN HALF OF THE
FCST AREA...WITH PROFILES POSSIBLY SUPPORTING WEAK TSRA. POPS ARE
REINTRODUCED LATE WITH CHANCES ALONG THE HIGH TERRAIN WHILE SLIGHT
CHANCES PREVAIL OVER THE FTHILLS AND WESTERN PIEDMONTS OF NC/SC AS
WELL AS NORTHEAST GA. EXPECTING OVERNIGHT LOWS TO BE GENERALLY 4-6
DEGREES ABOVE NORMAL WHILE HIGHS ON THURSDAY TOP OUT NEAR NORMAL.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
AS OF 210 PM WEDNESDAY...THE SHORT TERM WILL SEE THE BREAKING DOWN
OF THE OMEGA-BLOCK PATTERN THAT HAS BEEN IMPACTING THE WEATHER ACROSS
MUCH OF THE EAST FOR THE PAST WEEK OR SO...AS A PROGRESSIVE/COMPACT
UPPER LOW MOVES ACROSS THE OHIO VALLEY AND VICINITY THU NIGHT/
FRIDAY. WHILE THIS WILL BE THE GENERAL TREND...THE LATEST MODEL
GUIDANCE IS NOT IN THE GREATEST AGREEMENT REGARDING THE
TRACK/TIMING/INTENSITY OF THIS FEATURE AS IT PROGRESSES ACROSS THE
EASTERN CONUS. THERE ARE ESSENTIALLY TWO CAMPS...THE FARTHER
SOUTH/SLOWER/STRONGER SOLUTION (CANADIAN GEM AND THE NAM) AND THE
FARTHER NORTH/FASTER/WEAKER SOLUTION (THE GFS AND ECMWF). AS
SUCH...THE FORMER CAMP DEPICTS STRONGER FORCING/QPF ACROSS OUR AREA
DURING THE DAY FRIDAY (AS THIS BETTER FORCING INTERACTS WITH A MORE
UNSTABLE AIR MASS IN THIS SLOWER SCENARIO)... WHILE THE LATTER CAMP
DEPICTS CONSIDERABLY LIGHTER PRECIP ACROSS THE AREA THU NIGHT AND
EARLY FRIDAY. EVEN IF THE NAM/CANADIAN CAMP PROVES VERIFYING CLOSER
TO REALITY...THERE IS NOT EXACTLY IDEAL OVERLAP BETWEEN THE
STRONGEST FORCING...BUOYANCY...AND WIND SHEAR...WHICH MAY COMBINE TO
LIMIT THE OVERALL COVERAGE AND INTENSITY OF CONVECTION.
NEVERTHELESS...FROM A POP STANDPOINT IT WOULD APPEAR THAT LIKELIES
ARE WARRANTED ACROSS THE FORECAST AREA FRIDAY. THERE WILL BE A
CHANCE FOR A SEVERE STORM OR TWO ACROSS THE PIEDMONT FRI
AFTERNOON...ESP IF THE SLOWER MODEL SOLUTIONS END UP WORKING
OUT.
CONDITIONS WILL GRADUALLY CLEAR LATE FRI INTO SATURDAY...SETTING THE
STAGE FOR ANOTHER MOSTLY SUNNY SATURDAY (EXCEPT PERHAPS WITH SOME NW
FLOW CLOUDS POSSIBLE ACROSS THE FAR WESTERN NC MTNS) WITH TEMPS
AVERAGING A CATEGORY OR SO ABOVE CLIMO.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 310 AM WEDNESDAY...UPPER RIDGING BUILDS INTO THE AREA SUNDAY
WITH WEAK SHORT WAVE ENERGY CROSSING THE AREA MONDAY AND TUESDAY.
DURING THIS TIME...A STRONG UPPER LOW DEVELOPS OVER EASTERN QUEBEC
WHICH RETROGRADES BY THE END OF THE PERIOD. AT THE SURFACE...HIGH
PRESSURE CROSSES THE AREA SUNDAY AND MOVES INTO THE ATLANTIC MONDAY.
A COLD FRONT DROPS SOUTH TOWARD THE AREA MONDAY. ON TUESDAY...THE
GFS BRINGS THE FRONT SOUTH INTO THE AREA WHILE THE ECMWF KEEPS THE
FRONT NORTH OF THE AREA. BOTH MODELS DEVELOP A LOW PRESSURE CENTER
ALONG THE FRONT AS IT MOVES SOUTH. THE GFS BRINGS MORE IN THE WAY OF
PRECIP TO OUR AREA SINCE IT IS FARTHER SOUTH. HOWEVER...THE ECMWF
DOES SHOW PRECIP MOVING INTO AT LEAST THE NORTHERN CWFA. USING A
GUIDANCE BLEND KEEPS THE FORECAST DRY THROUGH MONDAY...WITH CHANCE
POP DEVELOPING FOR MAINLY THE MOUNTAINS ON TUESDAY.
WITH THE FRONT REMAINING NORTH OF THE AREA UNTIL VERY LATE IN THE
PERIOD...HIGHS WILL RISE BACK INTO THE 80S FOR MOST OF THE AREA BY
TUESDAY...WHILE LOWS RISE INTO THE 60S FOR MOST OF THE AREA.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AT KCLT/KHKY...ATLANTIC MOISTURE FLOWING OVER SHALLOW WEDGE OF HIGH
PRESSURE IS ALREADY PRODUCING MVFR CIGS OVER THE NC PIEDMONT. THE
NAM FAMILY OF MODELS IS HANDLING THE STRATUS MOST ACCURATELY
ATTM...SO USED A CONSENSUS OF NAM AND HRRR FOR CLOUD BASES THRU
THE MRNG. THEY GENERALLY SHOW AT LEAST BKN MVFR PERSISTING UNTIL A
COUPLE HRS AFTER DAYBREAK...AND HINT AT PATCHY IFR AS WELL. WITH
CIGS ALREADY DEVELOPING AND WITH DRY SFC DEWPOINTS...NOT SURE IF
SATURATION WILL OCCUR LOW ENOUGH TO BRING CIGS TO IFR...SO THAT IS
LEFT IN TEMPO. FOLLOWING THE DISSOLUTION OF THE STRATUS...MAINLY
MID-HIGH CLOUDS WILL BE SEEN TODAY. APPROACH OF COLD FRONT FROM THE
WEST TONIGHT WILL REINTRODUCE A LOW VFR DECK THIS EVENING. WINDS
WILL REMAIN SOUTHERLY...AND A FEW LOW-END GUSTS ARE POSSIBLE
THIS AFTN.
ELSEWHERE...MOST GUIDANCE KEEPS THE IFR CIGS EAST OF THE REMAINING
TAF SITES...BUT MVFR SHOULD EXPAND OVER KGSP/KGMU/KAVL BEFORE
DAWN. CAN/T TOTALLY RULE OUT IFR...SO I WILL KEEP AN EYE ON NEARBY
TRENDS AND AMD IF NECESSARY. THIS WILL BE THE MAIN IMPACTFUL WEATHER
THRU THE DAY TODAY...WITH SCT-BKN CIRRUS AND MODEST SOUTHERLY
WINDS. A SMALL CHC OF TSRA EXISTS OVER THE SW NC MTNS...BUT CHC
IS TOO LOW TO MENTION AT KAVL. COLD FRONT WILL BRING BETTER SHRA
CHANCES THIS EVENING FROM WEST TO EAST...HENCE PROB30 AT KAVL. MVFR
CIGS WILL PRECEDE THE FRONT...BUT ONLY KAND IS EXPECTED TO SEE
SUCH PRIOR TO 06Z.
OUTLOOK...RAIN CHANCES INCREASE EARLY FRI AHEAD OF ANOTHER COLD
FRONT APPROACHING THE AREA. HIGH PRESSURE AND MOSTLY VFR CONDITIONS
WILL RETURN SATURDAY FOLLOWING THE DEPARTURE OF THE FRONT.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 91% HIGH 95% HIGH 100% HIGH 100%
KGSP HIGH 91% HIGH 92% HIGH 100% HIGH 100%
KAVL HIGH 88% HIGH 88% HIGH 100% HIGH 83%
KHKY HIGH 92% HIGH 89% HIGH 100% HIGH 100%
KGMU HIGH 99% HIGH 94% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 92% HIGH 100% HIGH 91%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JMP
NEAR TERM...CDG/WIMBERLEY
SHORT TERM...JDL
LONG TERM...PM
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1249 AM CDT THU APR 21 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...A CLUSTER OF DISSIPATING THUNDERSTORMS HAS SLOWLY BEEN
MOVING FROM THE WESTERN PORTION OF DEEP SOUTH TEXAS AND THE RIO
GRANDE VALLEY INTO THE CENTRAL PORTION. LIGHT RAIN HAS DEVELOPED
WITHIN THE VICINITY OF MFE...AND SHOULD PERSIST THROUGH THE NEXT
FEW HOURS. MEANWHILE...IT IS ANTICIPATED THAT BRO AND HRL WILL
REMAIN DRY. MVFR CEILINGS ARE ALSO ANTICIPATED FOR THE REMAINDER
OF THE OVERNIGHT HOURS AND THROUGH THURSDAY MORNING. TOMORROW
AFTERNOON...VFR WILL RETURN WITH MODERATE SURFACE WINDS...WITH
VFR/MVFR ANTICIPATED TOMORROW NIGHT.
&&
.PREV DISCUSSION... /ISSUED 1001 PM CDT WED APR 20 2016/
DISCUSSION...ONGOING SEVERE THUNDERSTORMS AND HEAVY RAINFALL
CONTINUES OVER ZAPATA COUNTY LATE THIS EVENING. THE CONVECTION IS
EXPECTED TO WEAKEN OVER THE COUPLE OF HOURS AS THE ATMOSPHERE
BECOMES MORE STABLE. MADE A QUICK UPDATE TO INCREASE POPS ACROSS
ZAPATA COUNTY AND LOWER POPS ACROSS THE EASTERN PORTIONS OF DEEP
SOUTH TEXAS. THE REST OF THE FORECAST LOOKS GOOD AND NO OTHER
CHANGES NEEDED AT THIS TIME.
PREV DISCUSSION... /ISSUED 708 PM CDT WED APR 20 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...SATELLITE AND RADAR IMAGES INDICATE SOME ONGOING
CONVECTION WITH MID TO HIGH LEVEL CLOUDS OVER THE MOUNTAINS OF
NORTHEAST MEXICO THIS EVENING. WITH SURFACE INSTABILITY
RELATIVELY HIGH ACROSS THE PORTIONS OF DEEP SOUTH TEXAS AND WEST
TO EAST FLOW ALOFT...THERE IS A SMALL CHANCE THAT SOME STORMS
COULD MOVE INTO THE WESTERN PORTIONS OF THE CWA LATER THIS
EVENING. AN ISOLATED STORM COULD IMPACT MFE THROUGH LATE THIS
EVENING...SO WILL CONTINUE TO MENTION VCTS FOR MFE THROUGH 04Z.
OTHERWISE...MID TO HIGH LEVEL CLOUD COVER WILL INCREASE ACROSS THE
RIO GRANDE VALLEY THROUGH THIS EVENING DUE TO DEBRIS CLOUDS FROM
THE EARLIER STORMS OVER NORTHERN MEXICO. LOW CLOUDS EXPECTED TO
DEVELOP LATER THIS EVENING RESULTING IN MVFR TO POSSIBLE IFR
CEILINGS OVERNIGHT. VFR CONDITIONS WILL RETURN LATE THURSDAY
MORNING INTO EARLY AFTERNOON.
PREV DISCUSSION... /ISSUED 311 PM CDT WED APR 20 2016/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...SATELLITE AND RADAR
IMAGES INDICATE CONVECTION CONTINUING TO DEVELOP ACROSS NORTHEAST
MEXICO THIS AFTERNOON AND BOTH THE NAM AND HRRR CONTINUE TO
INDICATE CONVECTION DEVELOPING ACROSS EXTREME WESTERN PORTIONS OF
THE CWA LATE THIS AFTERNOON INTO THIS EVENING. WITH THE SURFACE
INSTABILITY REMAINING HIGH ACROSS THE RIO GRANDE VALLEY AND
NORTHERN RANCHLANDS...CANNOT RULE OUT THE POTENTIAL FOR ISOLATED
SEVERE THUNDERSTORMS ACROSS PORTIONS OF ZAPATA...JIM HOGG...AND
STARR COUNTIES THIS EVENING. THE GREATEST THREAT FOR SEVERE
APPEARS TO BE HAIL AND DAMAGING WINDS. HEAVY RAINFALL CAN BE
EXPECTED WITH SOME OF THE STRONGER TO SEVERE STORMS. WILL GO WITH
THE HIGHEST POPS ACROSS THE WESTERN PORTIONS OF THE CWA WITH LOWER
POPS TOWARDS THE COAST THIS EVENING.
THE FORECAST FOR THURSDAY AND THURS NIGHT IS CHALLENGING WITH THE
WEST TO NORTHWEST FLOW ALOFT BUT THE NAM AND GFS HAVE A CONVECTIVE
BOUNDARY DEVELOPING ACROSS PORTIONS OF CENTRAL TX THURSDAY AND AS
THIS FEATURE MOVES SOUTHWARD IT WILL PROVIDE A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE CWA THURSDAY INTO
THURS NIGHT AS MOISTURE POOLS ALONG AND AHEAD OF A WEAK COLD FRONT
MOVES SOUTHWARD ACROSS SOUTH TX.
LONG TERM /FRIDAY THROUGH WEDNESDAY/...UPPER LEVEL RIDGE WILL
BEGINS TO BUILD ACROSS THE DESERT SOUTHWEST INTO S TEXAS FRIDAY
WITH A WEAK FRONT MOVING SOUTH. WEAK FRONT COMBINED WITH PERTURBATIONS
WITHIN THE FLOW WILL ENHANCE SHOWERS AND THUNDERSTORMS ACROSS THE
CWA. THE BOUNDARY WILL STALLED OVER DEEP SOUTH TEXAS WITH WINDS
REMAINING EASTERLY INTO SATURDAY. AN ABUNDANT SURGE OF MOISTURE
WILL MOVE INTO THE AREA CONTINUING THE DEVELOPMENT OF MORE SHOWERS
AND THUNDERSTORMS ACROSS THE WESTERN COUNTIES THIS WEEKEND. MODEL
GUIDANCE CONTINUE TO SHOW ABOVE 1.5 IN OF PRECIPITABLE WATER
THROUGH THE WEEKEND WHICH WILL FAVOR THE DEVELOPMENT WITH THIS
TROUGH AS IT MOVES EASTWARD. DRIER AIR MASS MOVES INTO THE AREA
MONDAY WITH LESS SIDE TROUGH DEVELOPING OVER SOUTH CENTRAL TEXAS.
THIS WILL LIMIT THE POTENTIAL FOR RAIN BUT A FEW ISOLATED SHOWERS
CAN`T BE RULED NEAR THE COAST WITH THE SEABREEZE. THE RIDGE WILL
BE IN CONTROL OF THE AREA MONDAY AND TUESDAY LIMITING THE
POTENTIAL FOR RAIN THROUGH MID WEEK. THE SOUTHERLY FLOW WILL
INCREASE TO MORE BREEZE CONDITIONS MONDAY AS THE NEXT UPPER TROUGH
STRENGTHENS OVER THE PAC NORTHWEST. MODELS ARE IN PRETTY GOOD
AGREEMENT WITH GFS BEEN SLIGHTLY MORE PROGRESSIVE WITH THE NEXT
LOW PRESSURE SYSTEM WHILE THE ECMWF IS A BIT SLOWER. EVEN WITH THE
SLIGHT DIFFERENCE STILL SHOW THE POTENTIAL FOR RAIN FOR THE
WEEKEND AND THE DRY AIR FILTERING IN BY EARLY NEXT WEEK. LEAN
TOWARDS A BLEND OF THE TWO MODELS FOR THIS PACKAGE.
MARINE...TONIGHT THROUGH THURSDAY NIGHT...SEAS WERE NEAR 4 FEET
WITH EAST TO SOUTHEAST WINDS NEAR 10 KNOTS AT BUOY020 EARLY THIS
AFTERNOON. LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS TONIGHT INTO THURSDAY WITH LOW PRESSURE ACROSS
NORTHEAST MEXICO AND A WEAK COLD FRONT DRAPED ACROSS NORTH TEXAS.
THE BOUNDARY WILL MOVE INTO SOUTH TX THURS NIGHT AND THIS WILL
CONTINUE TO PROVIDE A WEAK PRESSURE GRADIENT ACROSS THE LOWER TX
COAST.
FRIDAY THROUGH TUESDAY...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
FOR THE EARLY PORTION OF THE LONG TERM PERIOD AS ABUNDANT MOISTURE
IN THE REGION WILL ALLOW FOR CONVECTION TO CONTINUE. EXPECT A
MODERATE SOUTHEAST FLOW ACROSS THE GULF WITH SEAS BETWEEN 2 TO 4
FEET THROUGH THE WEEKEND. RIDGE BEGINS TO BUILD LOWERING SEAS EVEN
LESS THAN 2 FEET SAT AND SUN. AN INFLUX OF MOISTURE WILL SURGE
NORTH SAT NIGHT INTO SUN INCREASING THE CHANCE OF SHOWERS ONCE
AGAIN. SEAS WILL BEGIN TO INCREASE INTO MONDAY AS A STRONG SURFACE
LOW STRENGTHENS OVER THE CENTRAL PLAINS. SEAS WILL BEGIN TO BUILD
TO 3 TO 6 FEET WITH SCEC POSSIBLE.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
337 AM CDT THU APR 21 2016
.TODAY AND TONIGHT...FORECAST CONFIDENCE - LOW TO MEDIUM.
FORECAST CONCERNS FOCUS ON PRECIP THREAT RETURNING TODAY AND FOG.
DRIER AIR WRAPPING AROUND UPSTREAM LOW PRESSURE ERODING LOW CLOUDS
OVER FAR SOUTHWEST WI AND WILL AFFECT SOUTHWEST CWA NEXT SEVERAL
HOURS. THIS WILL ALLOW FOG TO DEVELOP AND FOG COULD EASILY TURN
DENSE FOR SEVERAL HOURS. WITH EARLIER SUNRISE...WL HOLD OFF ON
ISSUING DENSE FOG ADVY FOR KEFT/KMRJ AREAS AND GO WITH SPS FOR
NOW...HOWEVER MAY NEED TO GO WITH ADVY SHOULD VSBYS RAPIDLY FALL
IN NEXT 1-2 HOURS. FOG SHOULD LIFT AFTER 13Z.
FARTHER EAST...EXPCT SCT -SHRA TO GRADUALLY DIMINISH THRU THE EARLY
MORNING AS LOW LEVEL MOISTURE ADVECTION WEAKENS. HRRR HAS BEEN
SHOWING SCT -SHRA REFORMING OVER CENTRAL AND EASTERN CWA EARLY THIS
MORNING BUT OTHER SHORT TERM GUIDANCE DRIER AND SUCCUMBING TO DRYING
MID-LEVEL AIR FROM THE SOUTHWEST. DIFFICULT TO FIND FORCING
MECHANISM FOR THESE -SHRA DEPICTED BY HRRR...SO WL GO WITH MAINLY
DRY CONDITIONS THIS MRNG ACROSS CENTRAL CWA AND KEEP SMALL CHANCE
FOR LINGERING -SHRA IN EAST FOR A FEW HOURS.
EXPECT LOW CLOUDS TO THIN ACROSS CENTRAL AND MOST OF EASTERN CWA
LATER THIS MRNG BUT MORE CLOUDS AND FOG MAY LINGER CLOSER TO THE
LAKE DUE TO LAKE BREEZE.
DESPITE WEAK SHEAR...DEWPOINTS IN THE 50S AND PARTIAL SUNSHINE
SHOULD RESULT IN MUCAPES INCREASING TO 300 TO 800 J THIS AFTN.
STRONGEST FORCING ASSOCIATED WITH UPPER LOW TO REMAIN TO THE SOUTH
OF THE IL BORDER THIS AFTN...HOWEVER WL STILL HAVE LOW PRESSURE TROF
MOVING THRU SRN WI. IN ADDITION...SRN CWA GETS GRAZED BY STRONGER
SYNOPTIC FORCING FROM LEFT EXIT REGION OF UPPER JET. HENCE EXPECT
SCT SHRA AND A FEW TSTRMS TO DEVELOP OVER CWA THIS AFTN INTO THE
EARLY EVE BEFORE DIMINISHING. BACK DOOR COLD FRONT WILL SWEEP
ACROSS CWA AFT MIDNIGHT USHERING COOLER AND DRIER AIR BACK INTO THE
REGION.
.FRIDAY AND FRIDAY NIGHT - CONFIDENCE...MEDIUM
CONSIDERABLE DAVA TAKES HOLD WITH INCOMING MID LEVEL RIDGING IN
THE WAKE OF DEPARTED SHORTWAVE INTO THE OHIO VALLEY. LOW LEVEL
COLD ADVECTION WELL UNDERWAY IN THE WAKE OF THE THURSDAY NIGHT
COLD FRONT. LLVL RH PROGS AND MOS DATA SUGGEST SOME MORNING
CLOUDINESS HANGING ON BUT THINGS SCOUR OUT IN THE AFTERNOON. MAIN
CONCERN THEN SHIFTS TO FROST POTENTIAL FOR LATER FRIDAY NIGHT.
SURFACE HIGH RIDGES IN AND WINDS ARE PROGGD TO BECOME QUITE LIGHT.
925 TEMPS ARE SUPPORTIVE OF THE CHILLY 30S THAT MOS IS GENERATING
SO HAVE INTRODUCED FROST INTO THE GRIDS FOR LATER FRIDAY NIGHT.
WHERE TEMPS ARE COLDEST AT SOME OF THE INTERIOR SECTIONS OF THE
CWA HAVE WENT WITH AREAS OF FROST WITH PATCHY ELSEWHERE. MAY END
UP NEEDING AN ADVISORY BUT AT THIS TIME WILL MENTION IN HWO.
.SATURDAY - CONFIDENCE...MEDIUM
SO AFTER A CHILLY START ANOTHER QUIET DAY IS IN STORE FOR SRN WI
WITH THE SURFACE RIDGE AXIS SHIFTING TO OUR EAST. THIS WILLS ET UP
A NICE RETURN AND 850/925 WAA. WARMUP WILL BE TEMPERED LAKESIDE AS
ONSHORE FLOW FROM THE SE WILL DOMINATE.
.SATURDAY NIGHT THROUGH MONDAY NIGHT - CONFIDENCE...MEDIUM
AN UNSETTLED PATTERN IS EXPECTED WITH SURFACE WARM FRONT SETTING UP
ACROSS CNTRL OR SRN WI. LOW PRESSURE IN THE NRN PLAINS WILL BE
DRIVEN BY APPROACHING MID LEVEL WAVE AND INCREASING DCVA THERE. SO
SHRA/TSRA INITIALLY WILL BE DRIVEN BY THE LLJ INTERACTION WITH THE
SFC/850 FRONTS IN THE STATE. THE SURFACE LOW IS THEN EXPECTED TO
WORK EASTWARD ALONG THE SFC FRONT SUNDAY NIGHT INTO MONDAY WHICH
WILL SUPPORT MORE ROUNDS OF SHRA/TSRA. IN ADDITION THERE WILL BE
TIMES WHEN THE LEFT FRONT EXIT REGION OF THE UPPER JET WILL BE
SITUATED FAVORABLY ACROSS SRN WI FOR ENHANCED LIFT. THE GFS
CONTINUES TO BE THE FASTER SOLUTION EXITING THIS PRECIP EARLY MONDAY
EVENING WHILE THE ECMWF HANGS ONTO SOME PRECIP ALL OF MONDAY NIGHT.
.TUESDAY - CONFIDENCE...LOW TO MEDIUM
DUE TO THE DIFFERING SPEEDS OF THIS SYSTEM THERE IS SOME TIMING
CONCERNS. THE GFS CONTINUES TO BE THE FASTEST SOLUTION WITH THE LOW
AND UPPER WAVE OFF TO OUR EAST WHILE THE ECMWF AND GEM SLOWER SPEED
SUGGESTS PRECIP COULD LINGER INTO TUESDAY MORNING. WILL GO WITH A
MORE PROGRESSIVE SOLUTION THAT THE GFS IS SHOWING AND THE SUPERBLEND
POPS TEND TO FAVOR THIS TREND. SO WILL GO DRY WITH A COOLER DAY AS
NORTHEAST WINDS AND SUBSIDENCE TAKE OVER DUE TO THE EXITING WAVE AND
LOW LEVEL CAA REGIME WITH INCOMING SFC HIGH.
.WEDNESDAY - CONFIDENCE...MEDIUM
PATTERN REMAINS FAIRLY ACTIVE WITH ANOTHER 500 MILLIBAR WAVE RIDING
NORTHEAST INTO THE UPPER MIDWEST. A SURFACE LOW DEVELOPS FROM THE
DAKOTAS AND MINNESOTA WITH POTENTIAL FOR A STRONG SOUTHERLY WAA
REGIME AND 925 TEMPS POSSIBLY GETTING BACK INTO THE TEENS CELSIUS.
WILL GO WITH THE SUPERBLEND POPS FOR MORE SHRA/TSRA. WILL HAVE TO
KEEP AN EYE ON THIS ONE. SYSTEM HAS SOME PRETTY HIGH CWASP NUMBERS
...ATTM THESE HIGHEST NUMBERS ARE JUST TO OUR SOUTH. DECENT
DYNAMICS. LONG WAYS OFF BUT FOR THIS FAR OUT SOME GOOD CONSENSUS
BETWEEN THE ECMWF AND GFS. SUPERBLEND TEMPS MAY BE TOO COOL GIVEN
THE POTENTIAL WARM SIGNAL WITH THE 850/925 TEMPS.
&&
.AVIATION/12Z TAFS/...LIGHT ONSHORE FLOW WL CONTINUE TO PULL LAKE
INDUCED FOG INTO ERN TAF SITES INTO THE MORNING...AND MAY LINGER
AT KMKE THRU MUCH OF THE DAY. HOWEVER LOWEST VSBYS ARE EXPECTED
THIS MRNG. OTHERWISE IFR CIGS OVER TAF SITES SHOULD SLOWLY LIFT
THIS MRNG AND SHOULD TRANSITION TO VFR... HOWEVER CONFIDENCE LOW
IN EAST DUE TO LAKE BREEZE AND PERSISTENT ONSHORE FLOW. A BRIEF
T-STORM MAY AFFECT TAF SITES THIS AFTN OR EARLY EVE. BACK DOOR
COLD FRONT WILL RESULT IN ABRUPT WIND SHIFT AND GUSTY WINDS LATER
TNGT.
&&
.MARINE...MOIST LOW LEVEL AIR HAS SPREAD INTO THE SOUTHERN PORTION
OF THE NEARSHORE WATERS. KENOSHA WEBCAMS SHOW DENSE FOG AT THE SHORE
WHERE DEWPOINTS HAVE RISEN INTO THE LOWER 50S. DEWPOINTS REMAIN A
LITTLE LOWER FARTHER NORTH TOWARD SHEBOYGAN...HOWEVER WEBCAMS IN
THIS AREA ARE ALSO SHOWING LOWERING VSBYS. LAKE MI TEMPS REMAIN
MOSTLY IN THE LOWER 40S SO COOL WATER AND LIGHT WINDS ARE RESULTING
IN AREAS OF DENSE FOG. WINDS ARE EXPECTED TO REMAIN LIGHT SOUTH TO
SOUTHEAST TODAY AS WEAK LOW PRESSURE APPROACHES. HENCE EXPECT
AREAS OF DENSE FOG TO PERSIST AND WILL POST MARINE DENSE FOG ADVY
UNTIL 00Z FRI.
LOW PRESSURE WILL EXIT REGION OVERNIGHT. TIGHTENING PRESSURE
GRADIENT TO THE NORTH WILL PULL BACK DOOR COLD FRONT ACROSS NEAR
SHORE AREA FROM 05Z THROUGH 10Z TONIGHT. ABRUPT WIND SHIFT TO THE
NORTH TO NORTHEAST CAN BE EXPECTED WITH A RAPID INCREASE IN WIND
GUSTS. WIND GUSTS MAY APPROACH 30 KTS FOR SEVERAL HOURS. HENCE WL
POST SMALL CRAFT ADVISORY FOR LATE TONIGHT THROUGH FRIDAY DUE TO
LINGERING HIGH WAVES.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
SMALL CRAFT ADVISORY FROM 2 AM TO 10 PM CDT FRIDAY FOR LMZ645-
646.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 PM CDT FRIDAY
FOR LMZ643-644.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...MBK
FRIDAY THROUGH WEDNESDAY...COLLAR
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
750 AM EDT THU APR 21 2016
.SYNOPSIS...
THE FRONTAL BOUNDARY WILL SHIFT BACK TO THE NORTHEAST TODAY.
ANOTHER COLD FRONT WILL CROSS THE AREA FRIDAY NIGHT. DRY HIGH
PRESSURE WILL BUILD BACK INTO THE REGION LATE SATURDAY THROUGH
TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE UPPER RIDGE WILL SHIFT OFF THE EAST COAST CREATING A MORE
S/SW FLOW REGIME AND MODERATE WARM ADVECTION ACROSS THE REGION.
THE STALLED FRONTAL BOUNDARY WILL LIFT TO THE NORTHEAST OUT OF THE
FORECAST AREA (FA) TODAY. UPPER LEVEL MOISTURE ADVECTION AND HIGH
CLOUDS WILL CONTINUE TO FLOW OVER THE REGION. DESPITE PARTLY
CLOUDY SKIES...LOCAL FORECAST TOOLS FAVOR THE WARMER TEMPERATURE
GUIDANCE DUE TO WARM ADVECTION AHEAD OF THE COLD FRONT. EXPECT
HIGHS IN THE LOW TO MID 80S.
HI RESOLUTION MODELS SHOW A SEA BREEZE BOUNDARY MOVING INLAND
INTO THE WESTERN FA LATE THIS AFTERNOON/EVENING. MID LEVEL DRY AIR
AND A SMALL CAPPING INVERSION WILL LIMIT CONVECTIVE DEVELOPMENT.
RECENT HRRR MODEL RUNS INDICATE SCATTERED TO ISOLATED SHOWERS
DEVELOPING ALONG THE COAST. WRF-ARW AND NMM MODELS ALSO KEEP
SHOWERS WEST OF THE AREA INCREASING CONFIDENCE IN A DRY FORECAST.
CLOSED UPPER TROUGH WILL CONTINUE TRACKING EASTWARD TOWARDS THE
REGION OVERNIGHT. SURFACE WARM FRONT SHOULD BE NORTH OF THE CWA TO
START THE PERIOD...WITH THE MAIN COLD FRONT STILL MOVING EAST OF
THE MISSISSIPPI RIVER. THIS PUTS THE REGION IN THE WARM SECTOR OF
THE NEXT SYSTEM. LOW-LEVEL FLOW OVERNIGHT WILL BE OUT OF THE
SOUTH TO SOUTHWEST...ALLOWING FOR AN INCREASE IN MOISTURE. DO
EXPECT THE EARLY PART OF TONIGHT TO BE DRY...THEN SHOULD SEE AN
INCREASE IN POPS FROM WEST TO EAST AFTER MIDNIGHT.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
UPPER TROUGH MOVING THROUGH THE EASTERN CONUS ON FRIDAY WILL
DRIVE COLD FRONT TOWARD THE REGION THROUGH THE DAY. EXPECT MAINLY
SHOWERS EARLY IN THE DAY FRIDAY...WITH POTENTIAL FOR ISOLATED
THUNDERSTORMS IN THE AFTERNOON AS THE AIR MASS BECOMES WEAKLY TO
MODERATELY UNSTABLE. STRONGER CONVECTION MORE LIKELY WEST OF THE
REGION BACK IN NORTHWEST GEORGIA. DECREASING POPS THROUGH THE
NIGHT FRIDAY INTO SATURDAY MORNING AS FRONT MOVES THROUGH THE
AREA. DRY CONDITIONS ONCE AGAIN FOR SATURDAY. GUIDANCE
TEMPERATURES THROUGH THE PERIOD SEEM REASONABLE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE TO SETTLE INTO THE CWA FROM SATURDAY THROUGH
MONDAY. MOISTURE INCREASE MID WEEK AND ANOTHER FRONT POSSIBLY
MOVING SOUTH FROM THE NORTH MAY LEAD TO ISOLATED OR SCATTERED
AFTERNOON SHOWERS TUESDAY AND WEDNESDAY. TEMPERATURES SHOULD BE AT
OR ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
ONSHORE FLOW BROUGHT LOW LEVEL MOISTURE TO AREA PRODUCING
IFR/MVFR CONDITIONS. LOW CLOUDS/FOG EXPECTED TO MIX OUT 14Z-15Z
AS INVERSION BREAKS AND WIND INCREASE. A COLD FRONT APPROACHING
FROM THE WEST AND A TIGHTENING PRESSURE GRADIENT WILL CREATE GUSTY
WINDS FROM MID-MORNING ON. BUFKIT FORECAST SOUNDINGS INDICATE THE
POTENTIAL FOR GUSTS 20 TO 25 KNOTS DURING THE AFTERNOON HOURS.
MODELS SUPPORT SHOWERS DEVELOPING AHEAD OF THE APPROACHING COLD
FRONT. THESE SHOWERS MAY REACH THE CENTRAL MIDLANDS AND CSRA TAF
SITES NEAR THE END OF THE TAF PERIOD...HOWEVER WILL KEEP OUT OF
TAFS FOR THE TIME BEING DUE TO TIMING UNCERTAINTY. LOW CIGS AHEAD
OF THE COLD FRONT MAY ALSO DEVELOP. THE SREF ENSEMBLE SUGGESTS THE
POTENTIAL FOR MVFR CIGS NEAR THE END OF THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE FRIDAY THROUGH
EARLY SATURDAY AS A COLD FRONT CROSSES THE REGION.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
956 AM CDT THU APR 21 2016
.UPDATE...
SATELLITE BEGINNING TO SHOW ENHANCED AREAS OF NEW CONVECTION
DEVELOPING ACROSS SOUTHEAST TEXAS AND THUS WE START ANEW AGAIN
WITH THE RAIN...IT`S COMING. WE HAVE A CONSISTENT MESSAGE...POPS
REMAIN HIGH ACROSS THE AREA...A FLASH FLOOD WATCH IS IN EFFECT
TODAY..WE HAVE A SATURATED GROUND ...AND FLOODING RAINS ARE
LIKELY TO OCCUR. DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE
ROADS...TURN AROUND DON`T DROWN. DO NOT GO NEAR CREEKS...DITCHES
OR DRIVE INTO LOW AREAS LIKE UNDERPASSES...THESE ARE REALLY
DANGEROUS PLACES TO BE IN FLASH FLOODING RAINS.
DEWPOINTS HAVE RECOVERED ACROSS SOUTHEAST TEXAS AND HRRR INDICATES
THIS WILL BE A FAVORABLE PLACE FOR FLOODING RAINS TO DEVELOP AND
MOVE EAST ACROSS THE I-10 CORRIDOR AREA. WPC INDICATING 2 TO 3
INCH RAINS COULD DEVELOP FAIRLY QUICKLY ONCE THE STORMS
BEGIN...THEREFORE ...FLASH FLOOD WARNINGS ARE LIKELY IN THE NEXT
FEW HOURS. STAY ABREAST OF THE WEATHER FOLKS.
NO CHANGES TO FORECAST...WILL LET IT RIDE.
&&
.PREV DISCUSSION... /ISSUED 648 AM CDT THU APR 21 2016/
AVIATION...SHOWER AND THUNDERSTORM ACTIVITY OVER THE SOUTHERN
PORTION OF THE AREA EARLIER HAS NOW SETTLED SOUTH INTO THE NEAR
COASTAL WATERS AND WEAKENED. REDEVELOPMENT IS EXPECTED LATE
MORNING AND THROUGH THE AFTERNOON OVER THE AREA AS ANOTHER WEATHER
DISTURBANCE APPROACHES FROM EAST TEXAS AND MOVES ACROSS THE
REGION. EARLY MORNING VISIBILITY RESTRICTIONS ALONG WITH IFR
STRATUS CEILINGS AT BPT AND AEX WILL BE LIFTING SHORTLY. MVFR INTO
VFR CEILINGS WILL GENERALLY PREVAIL AT ALL TERMINALS THROUGH THE
REMAINDER OF THE DAY.
PREV DISCUSSION... /ISSUED 423 AM CDT THU APR 21 2016/
DISCUSSION...
BUSY WEATHER PATTERN OVER THE REGION AS THE DISTURBANCE YESTERDAY
IS ANCHORED ALONG THE SOUTHERN LOUISIANA COAST THIS MORNING. THIS
SYSTEM IS EXPECTED TO MOVE EASTWARD THROUGH THE DAY. MEANWHILE
ANOTHER UPPER LEVEL DISTURBANCE IS MOVING INTO CENTRAL TEXAS THIS
MORNING AND LOOKS TO MAKE SOUTHEAST TEXAS DURING THE LATE MORNING/
EARLY AFTERNOON HOURS THEN MOVING INTO SOUTHERN LOUISIANA. THE
RECENT RAINS OVER THE LAST SEVERAL DAYS HAS PRODUCED RAINFALL
TOTAL OVER SIX INCHES IN SOME LOCATIONS AND TWO TO THREE INCHES
IS COMMON ACROSS MOST OF THE REGION. AS A RESULT... THE GROUND IS
COMPLETELY SATURATED... RAINS TODAY ARE EXPECTED TO FLOW INTO LOW
LYING AREAS...STREAMS AND BAYOUS. A FLASH FLOOD WATCH WILL
CONTINUE THROUGH THE MORNING INTO THE AFTERNOON HOURS.
ABOUT THE ONLY GOOD NEWS IS BEHIND THIS NEXT DISTURBANCE WILL BE A
SLOW MOVING COOL FRONT THAT WILL FINALLY BRING THE AREA SOME REST
FROM THE RECENT RAINS. FRIDAY AND INTO THE WEEKEND LOOKS TO BE
DRY. THE DOWN SIDE IS MORE RAINS ARE EXPECTED LATE SUNDAY INTO
MONDAY AS ANOTHER UPPER LEVEL DISTURBANCE MOVES INTO THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 78 62 80 59 / 70 40 20 10
LCH 78 66 81 63 / 70 40 20 10
LFT 80 66 81 62 / 70 40 30 10
BPT 79 64 82 63 / 70 30 20 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH UNTIL 6 PM CDT THIS EVENING FOR LAZ027>033-
041>045-052>055-073-074.
TX...FLASH FLOOD WATCH UNTIL 6 PM CDT THIS EVENING FOR TXZ180-201-215-
216-259>262.
GM...NONE.
&&
$$
PUBLIC...06
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1104 AM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE WESTERN ATLANTIC TODAY. A COLD FRONT
WILL APPROACH FROM THE WEST FRIDAY...PUSHING OFF THE COAST LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING. HIGH PRESSURE RETURNS FOR
SATURDAY AFTERNOON INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS AN UPPER LEVEL CLOSED LOW
OVER IA THIS MORNING...WITH AN UPPER LEVEL RIDGE OVER THE ERN CONUS.
AT THE SFC...HIGH PRESSURE HAS CENTERED OFFSHORE AS A BROAD AREA OF
LOW PRESSURE ASSOCIATED WITH THE UPPER LOW HAS LOCATED OVER THE
UPPER MIDWEST. THE ATTENDANT COLD FRONT EXTENDS SWWD INTO THE SRN
PLAINS. BETWEEN THESE SFC FEATURES...SLY/RETURN FLOW OVER THE LOCAL
AREA HAS RESULTED IN INCREASING MOISTURE/DEWPOINTS. AN INFLUX IN MID
LEVEL MOISTURE AHEAD OF THE APPROACHING STORM SYSTEM WILL RESULT IN
A PARTLY CLOUDY TO MOSTLY CLOUDY SKY TODAY. THE RAP INDICATES A WEAK
VORT MAX PUSHING ACROSS THE NRN NECK LATE THIS MORNING...WHICH IS
JUST ENOUGH FORCING TO PRODUCE ISOLATED LIGHT SHOWERS. ELSEWHERE...A
LACK OF APPRECIABLE FORCING AND STABLE CONDITIONS UNDER THE UPPER
LEVEL RIDGE WILL RESULT IN DRY CONDITIONS THRU MID AFTERNOON.
SHOWERS OVER THE NRN NECK EXPECTED TO DISSIPATE LATE MORNING/EARLY
AFTERNOON. A WARM FRONT LIFTS ACROSS THE REGION TODAY...WITH MODEST
DESTABILIZATION EXPECTED ACROSS SRN VA AND SE VA/NE NC. MOISTURE
RETURN AND LIFT INDICATED IN THE 300K SURFACES WILL RESULT IN
SHOWERS ACROSS THE AFOREMENTIONED REGION THIS AFTERNOON. AGAIN...A
LACK OF STRONG FORCING FOR ASCENT AND DEEP MOISTURE WILL RESULT IN
ONLY ISOLATED TO WIDELY SCATTERED LIGHT SHOWERS. RETURN FLOW OF 10
TO 15 MPH WILL PUSH TEMPS INTO THE LOW/MID 70S...EVEN WITH CLOUD
COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
EXPECT DRY CONDITIONS TO PREVAIL TNGT...AS A COLD FRONT WILL BE
PUSHING INTO/THRU THE OH AND TN VALLEYS. BUT...WILL KEEP SLIGHT
CHC/CHC POPS FOR EXTRM NW COUNTIES...IN CASE A FEW SHOWERS WELL IN
ADVANCE OF THE FRONT MAKE IT INTO THESE AREAS TWD FRI MORNG. IN
ADDITION...SMOKE FM FIRES IN ERN NC WILL SPREAD SMOKE NWD INTO NE
NC. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR THOSE AREAS
INTO EARLY FRI MORNG. MILD TNGT WITH LOWS IN THE UPR 50S TO LWR
60S.
AFOREMENTIONED UPR LO CONTINUES TO DE-AMPLIFY AS IT TRACKS THRU
THE OH VALLEY DURING FRI...PUSHING THE COLD FRONT INTO WRN VA/NC
BY 00Z SAT. PWATS PROGGED IN THE 1.25 TO 1.4 INCH RANGE AHEAD OF
THE FRONT (+1 STD DEV) FRI AFTN. FORECAST CONTINUES TO FAVOR THE
PROGRESSIVE RUNS OF THE GFS/ECMWF...WITH SHOWERS SPREADING INTO
THE PIEDMONT AND CNTRL VA FRI MORNG...AND THE REST OF THE AREA
FRI AFTN INTO FRI EVENG. INSTABILITY REMAINS MARGINAL ALONG WITH
MEAGER LAPSE RATES AND MODEST SHEAR. ALSO...LITTLE IF ANY
INSTABILITY EXISTS IN THE MIXED PHASE LAYER. HOWEVER...GIVEN THE
TIME OF DAY AND CLIMO...CANNOT RULE OUT EMBEDDED THUNDER AND WILL
LEAVE CHC IN THE FCST. MAIN CONCERN FRI WILL BE THE LACK OF
ADEQUATE FORCING FOR ASCENT...AS THE BEST HEIGHT FALLS REMAIN N
OF THE REGION. IF WE GET ENOUGH LIFT AND MOISTURE FEED...QPF AMTS
COULD RANGE FM .20 TO .40 INCH WITH THESE FRONT. WARM SECTOR AND
RETURN FLO WILL PUSH TEMPS INTO THE MID TO UPR 70S...EVEN WITH
MOSTLY CLOUDY CONDITIONS AND INCOMING PCPN. SHOWERS...AND POSSIBLY
A TSTM...WILL NOW LINGER OVR CNTRL/ERN COUNTIES INTO FRI NGT...AS
00Z/21 GFS/ECMWF MODEL RUNS ARE A LITTLE SLOWER. BULK OF PCPN WILL
MOVE OFF THE CST BY 12Z SAT.
MAINTAINED A SLGT CHC OVR THE REGION THRU SAT MORNG UNTIL THE UPR
TROF SHIFTS OFF THE CST BY 18Z. THEN...DRY CONDITIONS EXPECTED
SAT AFTN INTO SAT NGT...AS HI PRES BLDS IN FM THE NNW. ONLY
EXPECT MODEST CAA BEHIND THE FRONT...AS H85 TEMPS DROP ONLY A FEW
DEGS COMPARED TO FRI...RANGING FROM 6 TO 8C. EXPECT N WINDS OF 10
TO 15 MPH SAT. HIGHS GENERALLY IN THE LWR TO MID 70S (COOLER ALNG
THE CST).
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDS INTO THE MID-ATLANTIC SATURDAY NIGHT AND
GRADUALLY SLIDES OFFSHORE SUNDAY. MOSTLY CLEAR/SUNNY AND DRY
CONDITIONS ARE EXPECTED. LOWS SATURDAY NIGHT WILL BE SEASONALLY COOL
DROPPING INTO THE MID/UPPER 40S FOR MOST OF THE AREA...WITH LOW 50S
FOR SE COASTAL LOCATIONS. HIGHS SUNDAY MODERATE INTO THE LOW/MID 70S
FOR MOST OF THE AREA...BUT ONLY IN THE 60S FOR THE ERN SHORE DUE TO
LIGHT ONSHORE FLOW. THE HIGH SLIDES FARTHER OFFSHORE SUNDAY NIGHT
AND MONDAY AS A COLD FRONT APPROACHES FROM THE N MONDAY. 20/12Z
NUMERICAL GUIDANCE GENERALLY KEEPS THE BOUNDARY N OF THE LOCAL AREA
THROUGH THE DAY MONDAY...WHICH WOULD PLACE THE LOCAL AREA IN DEEP
LAYER SW FLOW WITH A MID/UPPER RIDGE BREAKING DOWN. THIS WOULD
RESULT IN A RATHER WARM DAY...AND HIGHS HAVE BEEN NUDGE UPWARD INTO
THE UPPER 70S/LOW 80S...WITH LOW/MID 70S FOR THE ERN SHORE UNDER A
PARTLY TO MOSTLY SUNNY SKY. THIS IS AFTER LOWS SUNDAY NIGHT IN THE
LOW/MID 50S. THE FRONT GRADUALLY DROPS THROUGH THE AREA TUESDAY. THE
MAIN FORCING ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH
GENERALLY PASSES N OF THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES
AS THE FEATURE PASSES OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY
20-30% (MAINLY N) AT THIS TIME. HIGHS TUESDAY ARE FORECAST TO BE IN
THE 70S AFTER MORNING LOWS IN THE 50S. HIGH PRESSURE BUILDS IN FROM
THE N TROUGH MIDWEEK...AS A LOW PRESSURE SYSTEM WITH LIMITED
MOISTURE APPROACHES FROM THE W. FORECAST HIGHS WEDNESDAY RANGE FROM
THE 60S ALONG THE COAST...TO THE LOW 70S INLAND.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS CONTINUE THROUGH THE FORECAST PERIOD. SURFACE HIGH
NOW LOCATED OFF THE MID ATLANTIC COAST WITH S WINDS AT 10 KTS OR
LESS. MOISTURE IN THE FORM OF HIGH AND MID LEVEL CLOUDS (4-5K FT
CU) WILL INCREASE AHEAD OF AN APPROACHING WARM FRONT TODAY. 00Z
MODEL GUIDANCE SUGGESTS AN ISOLATED SHOWER POSSIBLE BETWEEN 18Z-
00Z ACROSS SERN TAF SITES AS THIS BOUNDARY LIFTS NORTHWARD...BUT
CHANCE OF THIS AT ANY ONE SITE IS LOW SO PCPN WAS LEFT OUT OF
FORECAST FOR NOW. S-SW WINDS GUST 15-20 KT THIS AFTN AS PRESSURE
GRADIENT TIGHTENS BETWEEN THE DEPARTING HIGH AND APPROACHING LOW
TO THE WEST.
OUTLOOK...NEXT CHANCE FOR PRECIPITATION AND FLIGHT RESTRICTIONS
LOOKS TO BE FRI/FRI NIGHT (POTENTIALLY LINGERING THROUGH SAT
MORNING ACRS SE VA/NE NC) AS A COLD FRONT MOVES OFF THE COAST WITH
GRADUAL CLEARING OUT/DRIER AGAIN SATURDAY AFTN WITH DRY AND VFR
CONDS CONTINUING THROUGH MONDAY.
&&
.MARINE...
WINDS NOW SOUTH AROUND THE HIGH THAT HAS MOVED OFF THE COAST. SOME
CHANNELING POSSIBLE FROM TIME TO TIME TODAY AND TONIGHT...BUT THINK
WINDS WILL AVERAGE BELOW 20 KTS. WAVE GUIDANCE SUGGESTS SEAS OUT
NEAR BUOY 44009 REACH 5 FT FOR A FEW HOURS TONIGHT...BUT CONFIDENCE
IN THIS HAPPENING IS NOT THAT HIGH SO ELECTED TO HOLD OFF ON ANY
HEADLINE WITH THIS FORECAST PACKAGE.
OTW...NEXT CHANCE FOR ANY SCA HEADLINES WILL COME SAT MORNING AS
WINDS TURN NORTH BEHIND A COLD FRONTAL PASSAGE FRI NIGHT. CAA SURGE
APPEARS MINIMAL AT THIS POINT (15-20 KTS) ACROSS THE CHES BAY. HIGH
PRESSURE BUILDS OVER THE AREA SAT NIGHT AND SUN RESULTING IN BETTER
BOATING CONDITIONS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...SAM
SHORT TERM...SAM/TMG
LONG TERM...AJZ
AVIATION...MPR
MARINE...AJZ/MPR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
932 AM CDT THU APR 21 2016
.UPDATE...
ISSUED AT 911 AM CDT THU APR 21 2016
FOR MORNING UPDATE MAIN CHANGES WERE TO WIND AND CLOUD COVER.
LATEST MAV GUIDANCE HAS A PRETTY GOOD GRASP ON WINDS WHICH ARE
HIGHER THAN PREVIOUS FORECAST SUGGESTED. THEREFORE...HAVE
INCREASED WIND SPEEDS A BIT...PARTICULARLY OVER CENTRAL NORTH
DAKOTA. NEXT CONCERN IS CLOUD COVER WITH SOME EXPANDING AREAS OF
LOW CLOUDS. HRRR RUNS CONTINUE THE EXPANSION OF THE LOW CLOUD
COVER THROUGH THE MORNING...RAISING IT AND BREAKING IT UP IN THE
AFTERNOON. WILL ADDRESS THIS BY RAISING CLOUD COVER OVER MOST
AREAS.
UPDATE ISSUED AT 638 AM CDT THU APR 21 2016
NO CHANGES TO THE FORECAST OTHER THAN TO BLEND TO OBSERVED TRENDS
THROUGH 11 UTC AS THE SURFACE COLD FRONT HAS PROPAGATED THROUGH
NORTH DAKOTA EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT THU APR 21 2016
EARLY THIS MORNING A COLD FRONT CONTINUED TO PUSH SOUTHEAST ACROSS
THE STATE. MOST LOCATIONS HAVE SWITCHED OVER TO NORTHWEST WINDS
AND COLD AIR ADVECTION HAS TAKEN HOLD. TEMPERATURES TODAY WILL BE
COOLER WITH READINGS MAINLY IN THE 50S AS COLD AIR ADVECTION WILL
CONTINUE THROUGH THE DAY.
TONIGHT...HIGH PRESSURE SHIFTS OFF TO THE EAST AND RETURN FLOW
KICKS IN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU APR 21 2016
THE END OF THE WEEK LOOKS RATHER WARM. STRONG WARM AIR ADVECTION
AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM WILL COMBINE WITH
COMPRESSIONAL WARMING TO PRODUCE TEMPERATURES NEAR 80 ACROSS
PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA.
A POTENT SYSTEM IS TAKING AIM ON THE NORTHERN PLAINS FOR SATURDAY
AND SUNDAY. MODELS ARE IN SURPRISINGLY GOOD AGREEMENT WITH TIMING
AND PLACEMENT OF PRECIPITATION. THEREFORE...THUNDERSTORMS AND
WIDESPREAD RAINFALL APPEAR LIKELY AS A STACKED LOW DEVELOPS OVER
SOUTH DAKOTA. AT THIS TIME IT APPEARS PRECIPITATION AMOUNTS NEAR
AN INCH ARE POSSIBLE ACROSS PORTIONS OF SOUTHERN NORTH DAKOTA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 638 AM CDT THU APR 21 2016
VFR CONDITIONS ARE FORECAST FOR THE 12 UTC TAF CYCLE AS COOL HIGH
PRESSURE BUILDS ACROSS NORTH DAKOTA TODAY IN THE WAKE OF A COLD
FRONT OVERNIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1128 AM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE AND AN ACCOMPANYING FRONTAL SYSTEM WILL MOVE EAST
ACROSS THE MIDWEST AND OHIO VALLEY TOWARD THE REGION TODAY.
SHOWERS SPREADING INTO THE REGION THIS EVENING INTO FRIDAY WILL
BE FOLLOWED BY MILD AND DRY WEATHER THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VARYING AMOUNTS OF MID LEVEL CLOUDS WERE SPREADING EAST ACROSS THE
STATE LATE THIS MORNING. ANY RADAR RETURNS ARE WEAK WITH RAIN
EVAPORATING ABOUT 6-8 KFT AGL..IN THE DRY LOW TO MID LEVEL AIR.
TEMPS ARE RUNNING RIGHT ON TRACK WITH HOURLY GRIDDED DATA AND ON
TRACK TO REACH HIGHS IN THE U60S ACROSS THE NRN MTNS...AND LOWER
TO MID 70S ELSEWHERE.
LAST FEW RUNS OF THE HRRR HAVE SHOWN A SLIGHTLY BETTER CHC AND
EARLIER ONSET TIME FOR SCATTERED SHOWERS ACROSS WESTERN AND
CENTRAL PENN LATER THIS AFTERNOON /WEST/ AND EARLY THIS EVENING
/CENTRAL MTNS AND MID SUSQ VALLEY/. STILL...QPF THROUGH THE FIRST
HALF OF TONIGHT SHOULD BE LIGHT AND UNDER ONE TENTH OF AN INCH IN
MOST PLACES...WITH THE EXCEPTION OF THE NW MTNS THAT COULD SEE
AROUND 2 TENTHS OF AN INCH BY 06Z FRIDAY.
WINDS WILL BE SOUTHERLY...AND MAY BE 10-12MPH IN THE SE LATER IN
THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
UPPER LOW OVER THE PLAINS WILL OPEN UP A BIT AND JOIN UP WITH THE
LONG-WAVE TROUGH DROPPING INTO ERN CANADA. THE MOISTURE FEED GETS
BETTER TONIGHT AND FRIDAY...BUT THE UPPER LOW TAKES UNTIL FRI
EVENING/NIGHT TO MOVE OVERHEAD. THE SYSTEM SEEMS TO BE A LITTLE
SLOWER IN PASSING THAN IT APPEARED IN PREVIOUS DAYS. THE SFC LOW
STAYS WELL TO OUR NORTH AS IT OCCLUDES.
SHOWERS WILL BE SPOTTY OVERNIGHT AND HELD MAINLY TO THE NW
HALF/THIRD OF THE AREA. HOWEVER...A STRAY SHOWER MAY ESCAPE INTO
THE EAST. A VERY LOW POP IS WARRANTED FOR THE SE TONIGHT.
FRIDAY LOOKS PRETTY CLOUDY AND SHOWERY. TEMPS WILL STILL BE MILD
DUE TO THE MILD START AND CLOUD COVER. BUT MAXES WILL HOLD A
LITTLE CLOSER TO NORMS FRIDAY THAN THURS - AND MANY PREV DAYS.
THE FORCING WITH THIS SYSTEM IS NEBULOUS AND UPLIFT IS NOT VERY
ORGANIZED. WILL KEEP POPS LOWER THAN CATEGORICAL DUE TO THE
EXPECTED COVERAGE...WHICH SHOULD EVENTUALLY GET EVERY LOCATION
WET. BUT 100POPS SEEMS LIKE OVERKILL FOR THE LARGE BREAKS IN
BETWEEN THE NUMEROUS SHOWERS. FRIDAY NIGHT LOOKS LIKE IT COULD
STILL HOLD SOME SHOWERS...ESP IN THE S/SE AS THE UPPER LOW AND
REAL COLD AIR TAKE UNTIL MIDNIGHT OR SO ON FRIDAY NIGHT TO PASS
COMPLETELY THROUGH. PWATS IN THE 1 TO 1.25 INCH RANGE DO LAST FOR
ABOUT 24 HRS. BUT WITHOUT GOOD EASTERLY/OFF-ATLANTIC FLOW AND ONLY
QUESTIONABLE/DISORGANIZED FORCING...QPF IS STILL SLATED TO HOLD
TO ONLY 0.25 INCHES SE TO 0.6 INCHES NW. MINS FRI NIGHT WILL BE
REALLY CLOSE TO NORMALS NORTH AND JUST A HAIR ABOVE THEM IN THE
SOUTH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE COLD AIR BEHIND THE SERIES OF FRONTS WHICH MOVE THROUGH
FRIDAY AND FRIDAY NIGHT WILL BE MODIFIED AS IT MOVES THROUGH THE
UPPER PLAINS AND UPPER GREAT LAKES. THUS...TEMPS WILL NOT BE ALL
THAT COLD. MAXES SAT WILL BE JUST A DEG OR TWO COOLER THAN
NORMALS.
THE UPPER RIDGING OVER THE MIDWEST OVER THE WEEKEND WILL BE
SUPPRESSED SOUTHWARD IN THE FIRST HALF OF THE NEW WEEK. AN UPPER
LOW RIDING OVER THE RIDGE MON-TUES WILL BRING THE NEXT CHC OF
RAIN. WHAT LOOKS LIKE A POTENT STORM IN THE PLAINS/MIDWEST FILLS
AS THE UPPER LOW IS CAUGHT IN THE FASTER WESTERLIES. WARM FRONTAL
PRECIP SHOULD STAY TO THE NORTH OF THE AREA MONDAY. AT THIS POINT
THE WETTEST TIME LOOKS TO BE MON NIGHT-TUES. BUT THE PATTERN
REMAINS PROGRESSIVE AND AFTER ANOTHER DAY OR TWO OF HIGH PRESSURE
AND INCREASING TEMPS...ANOTHER SHOT AT RAIN WILL COME FOR THE
LATTER PART OF NEXT WEEK.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
A WARM FRONT LIFTING NORTHEAST INTO THE AREA WILL SPREAD SCT
SHOWERS INTO THE AREA /MAINLY NEAR AND TO THE WEST OF A KJST TO
KBFD LINE/ LATER TODAY.
DRY AIR IN THE LOW LVLS SHOULD ENSURE VFR CONDS ACROSS THE ENTIRE
AREA THROUGH MID AFTERNOON. HOWEVER...A BLEND OF LATEST NEAR TERM
MDLS SUGGEST A HEAVIER SHOWER THIS LATE AFTN OR EARLY EVENING
COULD PRODUCE A BRIEF VIS REDUCTION IN SOME SPOTS. BEST CHC WILL
BE ACROSS THE NW MTNS /KBFD/ AND LEAST CHC ARND KMDT/KLNS.
OUTLOOK...
FRI...SCT PM TSRA IMPACTS POSSIBLE.
SAT...EARLY AM LOW CIGS POSSIBLE W MTNS.
SUN...NO SIG WX EXPECTED.
MON...PM SHRA/REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...DANGELO
AVIATION...FITZGERALD/LAMBERT
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1042 AM EDT THU APR 21 2016
.DISCUSSION...
OBSERVED TEMPERATURES HAVE BEEN RUNNING A LITTLE HIGHER THAN
FORECAST IN A FEW SPOTS...AND THE LATEST MOS GUIDANCE SUPPORTS
RAISING TEMPERATURES A LITTLE FOR TODAY...MAINLY AROUND KNOXVILLE.
THE WARMER TEMPS WILL ALSO MEAN LOWER RH VALUES...INTO THE 25-30
PERCENT RANGE FROM KNOXVILLE TO SW VA. WEATHER CONDITIONS WILL NOT
BE HELPFUL FOR ONGOING WILDFIRES THIS AFTERNOON...WITH S-SW WINDS
OF 10-15 MPH...AND GUSTS TO 30 MPH IN THE MOUNTAINS.
FORTUNATELY...RAIN WILL BE MOVING INTO THE PLATEAU LATE THIS
AFTERNOON...BETWEEN 5 AND 8 PM ACCORDING TO THE HRRR AND RAP. THE
UPDATE WILL ADJUST POPS TODAY AND TONIGHT TO REFLECT THIS. AMOUNTS
OF A TENTH TO A QUARTER INCH ARE EXPECTED THROUGH TONIGHT...WITH
MORE POSSIBLE WITH A SECOND ROUND OF SHOWERS FRIDAY MORNING.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1143 AM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE ALONG THE COAST WILL CONTINUE TO MOVE EAST AND
OFFSHORE TODAY. A WARM FRONT WILL PASS NORTHEAST THROUGH THE
REGION TONIGHT AHEAD OF AN APPROACHING COLD FRONT THAT WILL
REMAIN JUST WEST OF THE MOUNTAINS THROUGH EARLY FRIDAY. THIS
FRONT SHOULD PUSH EAST ACROSS THE AREA FRIDAY AFTERNOON BRINGING
A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS
INTO FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1145 AM EDT THURSDAY...
ANOTHER MINOR UPDATE TO ACCOUNT FOR CLEARING STRATUS DECK IN EAST
AND ALSO DEEPER MIXING THAN PREVIOUSLY THOUGHT...LIKELY RESULTING
IN SOME STRONGER WIND GUSTS THROUGH THE AFTERNOON...IN THE 16 TO
24 MPH RANGE IN THE MOUNTAINS. TONGUE OF HIGHER DEW PT AIR HAS
PUSHED INTO THE NC FOOTHILLS BUT SHOULD MIX OUT OVER NEXT COUPLE
HOURS SO MADE SOME MINOR ADJUSTMENTS FOR THAT AS WELL. OTHERWISE
NO OTHER CHANGES AT THIS TIME.
PREV DISCUSSION AS OF 958 AM EDT THURSDAY...
BROKEN STRATUS DECK FROM MOIST SOUTHEASTERLY LOW LEVEL FLOW
BEGINNING TO ERODE QUICKLY WEST OF THE BLUE RIDGE...AND SATELLITE
AS WELL AS NEAR TERM MODELS SUGGEST THAT WILL CONTINUE FAIRLY
QUICKLY EAST OF BLUE RIDGE AS WELL. MEANWHILE...CLOUD COVER ACROSS
TN...KY...WV IS MAINLY MID TO HIGH AND FAIRLY THIN AND SO DO NOT
THINK THIS WILL HAVE MUCH IMPACT ON TEMPS. THUS BUMPED UP HIGH
TEMPS A FEW DEG AND HOPE THAT IS ENOUGH...AND ALSO REDUCED CLOUD
COVER SOMEWHAT.
HRRR AND SOME OTHER HI RES MODELS SUGGEST JUST BARELY ENOUGH
INSTABILITY IN CENTRAL NC AND VA TO GENERATE AN ISOLATED LATE
AFTERNOON SHOWER...BUT MOST LIKELY THIS WILL REMAIN JUST EAST OF
OUR FORECAST AREA...SO KEPT POPS BELOW 15 PERCENT BUT DID NUDGE
UPWARD AND WILL NEED TO MONITOR THIS AREA LATER TODAY FOR ANY
DEVELOPMENT IN CASE IT IS A LITTLE FARTHER WEST THAN EXPECTED.
OTHERWISE...MOST GUIDANCE CONTINUES TO SLOW DOWN APPROACH OF ANY
PRECIP AHEAD OF THE FRONT THAT IS CURRENTLY OVER NEAR THE
MISSISSIPPI RIVER. MAY NOT BE WORTH MENTIONING CHANCE POPS EVEN
IN FAR WEST UNTIL WELL AFTER MIDNIGHT. HRRR DOES SUGGEST SOME
SHOWERS ARRIVE IN FAR SW VA AROUND MIDNIGHT...BUT OTHER GUIDANCE
SHOWS THESE DISSIPATING AS THEY MOVE IN TO SOMEWHAT DRIER AIR.
THUS CONTINUED THE TREND OF REDUCING POPS THIS EVENING TO SLIGHT
CHC OR LESS...AND MAY NEED TO DO THIS EVEN MORE ON FUTURE UPDATES.
PREV DISCUSSION AS OF 222 AM EDT THURSDAY...
MOISTURE TO GRADUALLY RETURN ACROSS THE REGION OVER THE NEXT 24 HOURS
AS THE SURFACE-85H FLOW QUICKLY VEERS FROM SE THIS MORNING TO SW WHILE
INCREASING THIS AFTERNOON/OVERNIGHT AHEAD OF THE COLD FRONT TO THE
WEST. THIS LOW LOW LEVEL SOUTH/SE FLOW THIS MORNING WILL AGAIN ADVECT
LOW CLOUDS NOW OVER NORTH CAROLINA INTO AREAS MAINLY ALONG/EAST OF THE
BLUE RIDGE BEFORE GETTING BOOTED EAST THIS AFTERNOON AS THE FLOW TURNS
MORE SW. COULD EVEN SEE A SPOTTY LIGHT SHOWER OR SPOT OR TWO OF DRIZZLE
SOUTHERN BLUE RIDGE AND POINTS EAST THIS MORNING SO INCLUDED SOME
MENTION TO INIT. LATEST GUIDANCE INDICATES THAT MOST OF THE LOW CLOUDS
SHOULD BE EAST OF THE CWA BY MID AFTERNOON ALLOWING DEEPENING WARM
ADVECTION TO RETURN UNDER MOSTLY SHEARED MID/HIGH CLOUDS WITH
CONVECTION ALONG THE COLD FRONT TO THE WEST. MOISTURE ALONG WITH
LIFT/INSTABILITY APPEARS TOO LACKING TO PRODUCE MUCH IN THE WAY OF
SHOWERS THIS AFTERNOON DESPITE TEMPS WARMING BACK INTO THE 70S. THUS
CUTTING BACK ON POPS OUTSIDE OF THE FAR SW LATE WITH THINGS
TURNING BREEZY/MILD UNDER PARTLY SUNNY SKIES PER DRY AIR ALOFT.
WEAK RESIDUAL WARM FRONT WILL LIFT NE THROUGH THE REGION OVERNIGHT
RESULTING IN ADDED LOW LEVEL MOISTURE RETURN AS DEWPOINTS LOOK TO SURGE
INTO THE 50S. HOWEVER MOISTURE DEPTH WILL BE SHALLOW AND STILL LIMITED
BY MID LEVEL DRY AIR...SO POPS QUITE IFFY DURING THE EVENING AND MOSTLY
CONFINED TO THE FAR WEST AT BEST WHERE WILL KEEP SOME LOW CHANCE POPS.
UPPER LOW ACROSS THE MIDWEST SHOULD DRIFT MORE EASTWARD LATE TONIGHT
ALLOWING THE TRAILING SURFACE COLD FRONT TO WORK INTO THE OHIO/TN
VALLEY REGION BY DAYBREAK. GUIDANCE SUGGESTS POSSIBLE MULTIPLE BANDS OR
CLUSTERS OF DISORGANIZED SHOWERS LIKELY WITHIN THE PRE-FRONTAL AXIS OF
DEEP MOISTURE THAT LOOK TO PUSH OUT TO ALONG THE BLUE RIDGE. AGAIN THE
GFS REMAINS THE FASTEST WITH THE 00Z ECMWF MUCH SLOWER WITH SHOWERS
JUST TOUCHING THE FAR WESTERN COUNTIES BY 12Z. SINCE THE REMAINDER OF
THE SOLUTIONS AS WELL AS THE LATEST SREF SHOWING AT LEAST SOME SHOWERS
ACROSS THE MOUNTAINS...WILL CARRY MID LEVEL CHANCE POPS WEST OVERNIGHT
AND LOWER POPS EAST. OTRW BECOMING MOSTLY CLOUDY BUT QUITE MILD UNDER
SW BREEZES AND INCREASING MOISTURE WITH LOWS ONLY 50S TO AROUND 60 IN
SPOTS.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 235 AM EDT THURSDAY...
A COLD FRONT WILL MOVE EAST ACROSS THE REGION FRIDAY INTO FRIDAY
NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD AND ALONG THE
FRONT. SURFACE BASED CAPE VARIES AVERAGE AROUND 500-1000 J/KG AND
SURFACE BASED LIFTED INDICES ARE AROUND -2. THE DAY TWO CONVECTIVE
OUTLOOK PLACES OUR ENTIRE FORECAST AREA IN GENERAL THUNDERSTORMS
WITH A MARGINAL THREAT TO OUR SOUTH ACROSS ALABAMA AND GEORGIA.
HIGH TEMPERATURES FRIDAY WILL RANGE FROM THE MID 60S IN THE
MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
THE FRONT WILL EXIT THE AREA FRIDAY NIGHT WITH THE GREATEST
ABUNDANCE OF LINGERING SHOWERS ACROSS THE SOUTHEAST PORTION OF THE
AREA. LOW TEMPERATURES FRIDAY NIGHT WILL VARY FROM THE MID 40S IN
THE NORTHWEST MOUNTAINS TO THE MID 50S IN THE PIEDMONT.
ISOLATED SHOWERS WILL ALSO BE ASSOCIATED WITH PASSAGE OF THE 850 MB
FRONT AND INCREASING NORTHWEST FLOW ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA. THIS SHOWERS WILL LINGER SATURDAY MORNING. HIGH PRESSURE
WILL BUILD INTO THE AREA BY SATURDAY AFTERNOON BEHIND THE DEPARTING
COLD FRONT. HIGH TEMPERATURES SATURDAY WILL REACH READINGS FROM THE
UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS OUR AREA SATURDAY NIGHT
INTO SUNDAY. LOW TEMPERATURES SATURDAY WILL DROP TO AROUND 40 IN THE
COLDER MOUNTAINS VALLEYS TO NEAR 50 DEGREES IN THE PIEDMONT. SUNDAY
HIGH TEMPERATURES WILL WARM TO 70 DEGREES IN THE MOUNTAINS AND
APPROACH 80 DEGREES IN THE PIEDMONT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...
AN AXIS OF HIGH PRESSURE WILL SLOWLY PROGRESS ACROSS THE REGION INTO
EARLY NEXT WEEK. DRY AND PROGRESSIVELY MILDER CONDITIONS
ARE EXPECTED.
MONDAY NIGHT INTO WEDNESDAY...GUIDANCE IS VARIABLE REGARDING THE
APPROACH AND POSSIBLE PASSAGE OF A COLD FRONT. THE GFS IS MORE
PROGRESSIVE WHILE THE ECMWF IS SLOWER BY AROUND HALF OF A DAY.
ALSO...DIFFERENCES EXIST REGARDING A POTENTIAL SOUTHERLY WAVE MOVING
NORTHEAST ALONG THE FRONT ON WEDNESDAY...THAT BUCKLES THE FEATURE
BACK INTO OUR REGION. OUR FORECAST SOLUTION WILL REFLECT CLOSER TO
THAT OF THE ECMWF THAT HAS A SLOWER PROGRESSION...AND ALLOWS FOR
GREATER IMPACT FROM THE SOUTHERLY WAVE AND MORE ROBUST DAY OF
PRECIPITATION AND COOLER CONDITIONS ON WEDNESDAY.
TEMPERATURES WILL TREND MILDER DURING THIS PORTION OF THE FORECAST
THROUGH TUESDAY WHEN READINGS WILL AVERAGE FIVE TO TEN DEGREES ABOVE
NORMAL. WEDNESDAY IS EXPECTED TO BE COOLER WITH CLOUDS AND
PRECIPITATION ACROSS THE AREA.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM EDT THURSDAY...
MVFR TO OCNL IFR CIGS HAVE OVERSPREAD MUCH OF THE REGION...MAINLY
ALONG AND EAST OF THE BLUE RIDGE EARLY THIS MORNING...WITH MOSTLY
VFR TO THE NW AT KBLF/KLWB WHERE ON THE EDGE OF THE CANOPY.
LATEST GUIDANCE CONTINUES TO SHOW MUCH OF THIS LOWER CLOUD COVER
PERSISTING AND POSSIBLY BRIEFLY BACKING INTO THE SE WEST VA SITES
BEFORE SHIFTING EAST BY MID TO LATE MORNING. HOWEVER TIMING OF
IMPROVING CONDITIONS REMAINS IFFY WITH TRENDS SUGGESTING THAT MVFR
CIGS COULD LINGER EAST OF THE BLUE RIDGE UNTIL EARLY AFTERNOON. THUS
HAVE LOWERED CLOUD BASES A BIT MORE AS CURRENT OBS SUPPORT SOME
BRIEF IFR CIGS AND SPOTTY -SHRA BEFORE THE FLOW TURNS MORE
SOUTH/SW BY AFTERNOON AND THINGS MIX OUT PER LATEST BUFKIT RAOBS.
OTHERWISE MODELS SEEM TO HAVE A GOOD HANDLE ON THE LOW LEVEL
MOISTURE AND BEGIN PULLING IT OUT TO THE EAST BY THIS AFTERNOON
WITH ALL SITES VFR BY EARLY TO MID AFTERNOON IF NOT SOONER. WINDS
WILL GENERALLY BE LIGHT WITH SOME DIURNAL GUSTY CONDITIONS
BECOMING ESTABLISHED LATE THIS MORNING...AND THEN INCREASING FROM
THE SOUTH/SW AS THE LOW LEVEL JET PICKS UP. COULD SEE SOME GUSTS
TO 20-25 KNOTS ONCE LOW CLOUDS EXIT LEAVING MAINLY MID AND HIGH
CLOUDS DURING THE AFTERNOON.
WEAK WARM FRONT WILL DRIFT NORTH THROUGH THE AREA OVERNIGHT WHILE
DEEPER MOISTURE SHOULD REMAIN LIMITED TO AREAS JUST WEST OF THE
MOUNTAINS UNTIL LATE TONIGHT. BANDS OF SHOWERS COULD WORK EAST
INTO THE KBLF/KLWB VICINITY WELL AFTER MIDNIGHT WITH THE APPROACH
OF THE UPSTREAM COLD FRONT. HOWEVER SLOWER MODEL TIMING WOULD
SUGGEST THAT MOST AREAS WILL STAY VFR OVERNIGHT UNTIL LATE WHEN
CIGS COULD FALL INTO MVFR LEVELS MOUNTAINS WITH SHRA POSSIBLE.
EXTENDED AVIATION DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG WITH A COLD FRONT OVER
THE MIDWEST STATES WILL BEGIN TO BRING AN INCREASE IN DEEPER
MOISTURE AND COULD RESULT IN PERIODS OF SUB-VFR CEILINGS AS WELL
AS SHOWERS AND ISOLATED THUNDERSTORMS FRIDAY....WITH BEST
PROBABILITY IN THE MOUNTAINS FRIDAY MORNING AND OUT EAST IN THE
AFTERNOON. VFR SHOULD RETURN BEHIND THE FRONT FOR THE WEEKEND INTO
MONDAY AS HIGH PRESSURE CROSSES THE REGION. HOWEVER SOME LOWER
CIGS MIGHT REDEVELOP ACROSS THE MOUNTAINS BY SUNDAY AS LIGHT
EASTERLY FLOW SETS UP UNDER ANOTHER WEAK WEDGE WHICH SHOULD FADE
BY EARLY NEXT WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SK
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH/MBS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1000 AM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE ALONG THE COAST WILL CONTINUE TO MOVE EAST AND
OFFSHORE TODAY. A WARM FRONT WILL PASS NORTHEAST THROUGH THE
REGION TONIGHT AHEAD OF AN APPROACHING COLD FRONT THAT WILL
REMAIN JUST WEST OF THE MOUNTAINS THROUGH EARLY FRIDAY. THIS
FRONT SHOULD PUSH EAST ACROSS THE AREA FRIDAY AFTERNOON BRINGING
A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS
INTO FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 958 AM EDT THURSDAY...
BROKEN STRATUS DECK FROM MOIST SOUTHEASTERLY LOW LEVEL FLOW
BEGINNING TO ERODE QUICKLY WEST OF THE BLUE RIDGE...AND SATELLITE
AS WELL AS NEAR TERM MODELS SUGGEST THAT WILL CONTINUE FAIRLY
QUICKLY EAST OF BLUE RIDGE AS WELL. MEANWHILE...CLOUD COVER ACROSS
TN...KY...WV IS MAINLY MID TO HIGH AND FAIRLY THIN AND SO DO NOT
THINK THIS WILL HAVE MUCH IMPACT ON TEMPS. THUS BUMPED UP HIGH
TEMPS A FEW DEG AND HOPE THAT IS ENOUGH...AND ALSO REDUCED CLOUD
COVER SOMEWHAT.
HRRR AND SOME OTHER HI RES MODELS SUGGEST JUST BARELY ENOUGH
INSTABILITY IN CENTRAL NC AND VA TO GENERATE AN ISOLATED LATE
AFTERNOON SHOWER...BUT MOST LIKELY THIS WILL REMAIN JUST EAST OF
OUR FORECAST AREA...SO KEPT POPS BELOW 15 PERCENT BUT DID NUDGE
UPWARD AND WILL NEED TO MONITOR THIS AREA LATER TODAY FOR ANY
DEVELOPMENT IN CASE IT IS A LITTLE FARTHER WEST THAN EXPECTED.
OTHERWISE...MOST GUIDANCE CONTINUES TO SLOW DOWN APPROACH OF ANY
PRECIP AHEAD OF THE FRONT THAT IS CURRENTLY OVER NEAR THE
MISSISSIPPI RIVER. MAY NOT BE WORTH MENTIONING CHANCE POPS EVEN
IN FAR WEST UNTIL WELL AFTER MIDNIGHT. HRRR DOES SUGGEST SOME
SHOWERS ARRIVE IN FAR SW VA AROUND MIDNIGHT...BUT OTHER GUIDANCE
SHOWS THESE DISSIPATING AS THEY MOVE IN TO SOMEWHAT DRIER AIR.
THUS CONTINUED THE TREND OF REDUCING POPS THIS EVENING TO SLIGHT
CHC OR LESS...AND MAY NEED TO DO THIS EVEN MORE ON FUTURE UPDATES.
AS OF 222 AM EDT THURSDAY...
MOISTURE TO GRADUALLY RETURN ACROSS THE REGION OVER THE NEXT 24 HOURS
AS THE SURFACE-85H FLOW QUICKLY VEERS FROM SE THIS MORNING TO SW WHILE
INCREASING THIS AFTERNOON/OVERNIGHT AHEAD OF THE COLD FRONT TO THE
WEST. THIS LOW LOW LEVEL SOUTH/SE FLOW THIS MORNING WILL AGAIN ADVECT
LOW CLOUDS NOW OVER NORTH CAROLINA INTO AREAS MAINLY ALONG/EAST OF THE
BLUE RIDGE BEFORE GETTING BOOTED EAST THIS AFTERNOON AS THE FLOW TURNS
MORE SW. COULD EVEN SEE A SPOTTY LIGHT SHOWER OR SPOT OR TWO OF DRIZZLE
SOUTHERN BLUE RIDGE AND POINTS EAST THIS MORNING SO INCLUDED SOME
MENTION TO INIT. LATEST GUIDANCE INDICATES THAT MOST OF THE LOW CLOUDS
SHOULD BE EAST OF THE CWA BY MID AFTERNOON ALLOWING DEEPENING WARM
ADVECTION TO RETURN UNDER MOSTLY SHEARED MID/HIGH CLOUDS WITH
CONVECTION ALONG THE COLD FRONT TO THE WEST. MOISTURE ALONG WITH
LIFT/INSTABILITY APPEARS TOO LACKING TO PRODUCE MUCH IN THE WAY OF
SHOWERS THIS AFTERNOON DESPITE TEMPS WARMING BACK INTO THE 70S. THUS
CUTTING BACK ON POPS OUTSIDE OF THE FAR SW LATE WITH THINGS
TURNING BREEZY/MILD UNDER PARTLY SUNNY SKIES PER DRY AIR ALOFT.
WEAK RESIDUAL WARM FRONT WILL LIFT NE THROUGH THE REGION OVERNIGHT
RESULTING IN ADDED LOW LEVEL MOISTURE RETURN AS DEWPOINTS LOOK TO SURGE
INTO THE 50S. HOWEVER MOISTURE DEPTH WILL BE SHALLOW AND STILL LIMITED
BY MID LEVEL DRY AIR...SO POPS QUITE IFFY DURING THE EVENING AND MOSTLY
CONFINED TO THE FAR WEST AT BEST WHERE WILL KEEP SOME LOW CHANCE POPS.
UPPER LOW ACROSS THE MIDWEST SHOULD DRIFT MORE EASTWARD LATE TONIGHT
ALLOWING THE TRAILING SURFACE COLD FRONT TO WORK INTO THE OHIO/TN
VALLEY REGION BY DAYBREAK. GUIDANCE SUGGESTS POSSIBLE MULTIPLE BANDS OR
CLUSTERS OF DISORGANIZED SHOWERS LIKELY WITHIN THE PRE-FRONTAL AXIS OF
DEEP MOISTURE THAT LOOK TO PUSH OUT TO ALONG THE BLUE RIDGE. AGAIN THE
GFS REMAINS THE FASTEST WITH THE 00Z ECMWF MUCH SLOWER WITH SHOWERS
JUST TOUCHING THE FAR WESTERN COUNTIES BY 12Z. SINCE THE REMAINDER OF
THE SOLUTIONS AS WELL AS THE LATEST SREF SHOWING AT LEAST SOME SHOWERS
ACROSS THE MOUNTAINS...WILL CARRY MID LEVEL CHANCE POPS WEST OVERNIGHT
AND LOWER POPS EAST. OTRW BECOMING MOSTLY CLOUDY BUT QUITE MILD UNDER
SW BREEZES AND INCREASING MOISTURE WITH LOWS ONLY 50S TO AROUND 60 IN
SPOTS.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 235 AM EDT THURSDAY...
A COLD FRONT WILL MOVE EAST ACROSS THE REGION FRIDAY INTO FRIDAY
NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD AND ALONG THE
FRONT. SURFACE BASED CAPE VARIES AVERAGE AROUND 500-1000 J/KG AND
SURFACE BASED LIFTED INDICES ARE AROUND -2. THE DAY TWO CONVECTIVE
OUTLOOK PLACES OUR ENTIRE FORECAST AREA IN GENERAL THUNDERSTORMS
WITH A MARGINAL THREAT TO OUR SOUTH ACROSS ALABAMA AND GEORGIA.
HIGH TEMPERATURES FRIDAY WILL RANGE FROM THE MID 60S IN THE
MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
THE FRONT WILL EXIT THE AREA FRIDAY NIGHT WITH THE GREATEST
ABUNDANCE OF LINGERING SHOWERS ACROSS THE SOUTHEAST PORTION OF THE
AREA. LOW TEMPERATURES FRIDAY NIGHT WILL VARY FROM THE MID 40S IN
THE NORTHWEST MOUNTAINS TO THE MID 50S IN THE PIEDMONT.
ISOLATED SHOWERS WILL ALSO BE ASSOCIATED WITH PASSAGE OF THE 850 MB
FRONT AND INCREASING NORTHWEST FLOW ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA. THIS SHOWERS WILL LINGER SATURDAY MORNING. HIGH PRESSURE
WILL BUILD INTO THE AREA BY SATURDAY AFTERNOON BEHIND THE DEPARTING
COLD FRONT. HIGH TEMPERATURES SATURDAY WILL REACH READINGS FROM THE
UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS OUR AREA SATURDAY NIGHT
INTO SUNDAY. LOW TEMPERATURES SATURDAY WILL DROP TO AROUND 40 IN THE
COLDER MOUNTAINS VALLEYS TO NEAR 50 DEGREES IN THE PIEDMONT. SUNDAY
HIGH TEMPERATURES WILL WARM TO 70 DEGREES IN THE MOUNTAINS AND
APPROACH 80 DEGREES IN THE PIEDMONT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...
AN AXIS OF HIGH PRESSURE WILL SLOWLY PROGRESS ACROSS THE REGION INTO
EARLY NEXT WEEK. DRY AND PROGRESSIVELY MILDER CONDITIONS
ARE EXPECTED.
MONDAY NIGHT INTO WEDNESDAY...GUIDANCE IS VARIABLE REGARDING THE
APPROACH AND POSSIBLE PASSAGE OF A COLD FRONT. THE GFS IS MORE
PROGRESSIVE WHILE THE ECMWF IS SLOWER BY AROUND HALF OF A DAY.
ALSO...DIFFERENCES EXIST REGARDING A POTENTIAL SOUTHERLY WAVE MOVING
NORTHEAST ALONG THE FRONT ON WEDNESDAY...THAT BUCKLES THE FEATURE
BACK INTO OUR REGION. OUR FORECAST SOLUTION WILL REFLECT CLOSER TO
THAT OF THE ECMWF THAT HAS A SLOWER PROGRESSION...AND ALLOWS FOR
GREATER IMPACT FROM THE SOUTHERLY WAVE AND MORE ROBUST DAY OF
PRECIPITATION AND COOLER CONDITIONS ON WEDNESDAY.
TEMPERATURES WILL TREND MILDER DURING THIS PORTION OF THE FORECAST
THROUGH TUESDAY WHEN READINGS WILL AVERAGE FIVE TO TEN DEGREES ABOVE
NORMAL. WEDNESDAY IS EXPECTED TO BE COOLER WITH CLOUDS AND
PRECIPITATION ACROSS THE AREA.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM EDT THURSDAY...
MVFR TO OCNL IFR CIGS HAVE OVERSPREAD MUCH OF THE REGION...MAINLY
ALONG AND EAST OF THE BLUE RIDGE EARLY THIS MORNING...WITH MOSTLY
VFR TO THE NW AT KBLF/KLWB WHERE ON THE EDGE OF THE CANOPY.
LATEST GUIDANCE CONTINUES TO SHOW MUCH OF THIS LOWER CLOUD COVER
PERSISTING AND POSSIBLY BRIEFLY BACKING INTO THE SE WEST VA SITES
BEFORE SHIFTING EAST BY MID TO LATE MORNING. HOWEVER TIMING OF
IMPROVING CONDITIONS REMAINS IFFY WITH TRENDS SUGGESTING THAT MVFR
CIGS COULD LINGER EAST OF THE BLUE RIDGE UNTIL EARLY AFTERNOON. THUS
HAVE LOWERED CLOUD BASES A BIT MORE AS CURRENT OBS SUPPORT SOME
BRIEF IFR CIGS AND SPOTTY -SHRA BEFORE THE FLOW TURNS MORE
SOUTH/SW BY AFTERNOON AND THINGS MIX OUT PER LATEST BUFKIT RAOBS.
OTHERWISE MODELS SEEM TO HAVE A GOOD HANDLE ON THE LOW LEVEL
MOISTURE AND BEGIN PULLING IT OUT TO THE EAST BY THIS AFTERNOON
WITH ALL SITES VFR BY EARLY TO MID AFTERNOON IF NOT SOONER. WINDS
WILL GENERALLY BE LIGHT WITH SOME DIURNAL GUSTY CONDITIONS
BECOMING ESTABLISHED LATE THIS MORNING...AND THEN INCREASING FROM
THE SOUTH/SW AS THE LOW LEVEL JET PICKS UP. COULD SEE SOME GUSTS
TO 20-25 KNOTS ONCE LOW CLOUDS EXIT LEAVING MAINLY MID AND HIGH
CLOUDS DURING THE AFTERNOON.
WEAK WARM FRONT WILL DRIFT NORTH THROUGH THE AREA OVERNIGHT WHILE
DEEPER MOISTURE SHOULD REMAIN LIMITED TO AREAS JUST WEST OF THE
MOUNTAINS UNTIL LATE TONIGHT. BANDS OF SHOWERS COULD WORK EAST
INTO THE KBLF/KLWB VICINITY WELL AFTER MIDNIGHT WITH THE APPROACH
OF THE UPSTREAM COLD FRONT. HOWEVER SLOWER MODEL TIMING WOULD
SUGGEST THAT MOST AREAS WILL STAY VFR OVERNIGHT UNTIL LATE WHEN
CIGS COULD FALL INTO MVFR LEVELS MOUNTAINS WITH SHRA POSSIBLE.
EXTENDED AVIATION DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG WITH A COLD FRONT OVER
THE MIDWEST STATES WILL BEGIN TO BRING AN INCREASE IN DEEPER
MOISTURE AND COULD RESULT IN PERIODS OF SUB-VFR CEILINGS AS WELL
AS SHOWERS AND ISOLATED THUNDERSTORMS FRIDAY....WITH BEST
PROBABILITY IN THE MOUNTAINS FRIDAY MORNING AND OUT EAST IN THE
AFTERNOON. VFR SHOULD RETURN BEHIND THE FRONT FOR THE WEEKEND INTO
MONDAY AS HIGH PRESSURE CROSSES THE REGION. HOWEVER SOME LOWER
CIGS MIGHT REDEVELOP ACROSS THE MOUNTAINS BY SUNDAY AS LIGHT
EASTERLY FLOW SETS UP UNDER ANOTHER WEAK WEDGE WHICH SHOULD FADE
BY EARLY NEXT WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SK
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH/MBS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1006 AM CDT THU APR 21 2016
.UPDATE...
SHOULD SEE A MIX OF SUN AND CLOUDS TODAY...AS BEGINNING TO SEE
MORE HOLES IN THE CLOUD DECK THIS MORNING. WITH TEMPS ALREADY IN
THE LOW 60S MANY PLACES...FORECAST HIGHS IN THE UPPER 60S SEEM TO
BE ON TRACK. WITH WEAK SURFACE WINDS...WILL LIKELY SEE A LAKE
BREEZE DEVELOP. TEMPS NEAR THE LAKE TODAY WILL BE DEPENDENT ON
TIMING OF HOLES IN THE CLOUDS VS HOW QUICKLY THE LAKE BREEZE MOVES
INLAND. WILL MAINTAIN UPPER 50S AND LOW 60S NEAR THE LAKE FOR NOW.
WILL SEE SOME SCATTERED SHOWERS DEVELOP THIS AFTERNOON...WITH A
LITTLE THUNDER ALSO POSSIBLE. BEST CHANCE FOR SHOWERS/STORMS WILL
BE ACROSS THE SOUTHERN HALF OF THE FORECAST AREA.
&&
.AVIATION/18Z TAFS/...
THERE IS A CHANCE OF SHOWERS THIS AFTERNOON AND EVENING...WITH
CONDITIONS TURNING DRY TONIGHT INTO FRIDAY AS HIGH PRESSURE MOVES
INTO THE AREA.
SOME LOW CIGS/VSBYS WILL LINGER INTO LATE MORNING IN THE
EAST...WITH VFR CONDITIONS LIKELY TO RETURN MOST PLACES THIS
AFTERNOON.
WINDS WILL BE LIGHT AND VARIABLE MUCH OF THE DAY...BECOMING
NORTHERLY AND BREEZY THIS EVENING AND OVERNIGHT AS A COLD FRONT
DROPS SOUTHWARD THROUGH THE FORECAST AREA. LOWER CIGS ARE POSSIBLE
BEHIND THIS FRONT...EVENTUALLY MIXING OUT FRIDAY AFTERNOON.
&&
.MARINE...
DENSE FOG WILL REMAIN A CONCERN FOR THE NEARSHORE WATERS TODAY WITH
A MILD AND MOIST LOW-LEVEL AIRMASS IN PLACE ATOP THE COOLER LAKE
WATERS. LIGHT SOUTH TO SOUTHEASTERLY WINDS WILL CONTINUE...WITH THE
MARINE DENSE FOG ADVISORY REMAINING IN EFFECT UNTIL 00Z FRIDAY.
THEREAFTER...A BACK DOOR COLD FRONT WILL PUSH SOUTH THROUGH THE
COASTAL WATERS FROM ROUGHLY 05Z TO 10Z TONIGHT. EXPECT A RAPID
INCREASE IN WIND GUSTS DURING THIS TIME...ALONG WITH A NORTH TO
NORTHEASTERLY WIND SHIFT FOLLOWING THE FRONTAL PASSAGE. A SMALL
CRAFT ADVISORY FOR WINDS AND WAVES IS IN EFFECT FROM LATE TONIGHT
THROUGH FRIDAY.
&&
.PREV DISCUSSION... /ISSUED 337 AM CDT THU APR 21 2016/
TODAY AND TONIGHT...FORECAST CONFIDENCE - LOW TO MEDIUM.
FORECAST CONCERNS FOCUS ON PRECIP THREAT RETURNING TODAY AND FOG.
DRIER AIR WRAPPING AROUND UPSTREAM LOW PRESSURE ERODING LOW CLOUDS
OVER FAR SOUTHWEST WI AND WILL AFFECT SOUTHWEST CWA NEXT SEVERAL
HOURS. THIS WILL ALLOW FOG TO DEVELOP AND FOG COULD EASILY TURN
DENSE FOR SEVERAL HOURS. WITH EARLIER SUNRISE...WL HOLD OFF ON
ISSUING DENSE FOG ADVY FOR KEFT/KMRJ AREAS AND GO WITH SPS FOR
NOW...HOWEVER MAY NEED TO GO WITH ADVY SHOULD VSBYS RAPIDLY FALL
IN NEXT 1-2 HOURS. FOG SHOULD LIFT AFTER 13Z.
FARTHER EAST...EXPCT SCT -SHRA TO GRADUALLY DIMINISH THRU THE EARLY
MORNING AS LOW LEVEL MOISTURE ADVECTION WEAKENS. HRRR HAS BEEN
SHOWING SCT -SHRA REFORMING OVER CENTRAL AND EASTERN CWA EARLY THIS
MORNING BUT OTHER SHORT TERM GUIDANCE DRIER AND SUCCUMBING TO DRYING
MID-LEVEL AIR FROM THE SOUTHWEST. DIFFICULT TO FIND FORCING
MECHANISM FOR THESE -SHRA DEPICTED BY HRRR...SO WL GO WITH MAINLY
DRY CONDITIONS THIS MRNG ACROSS CENTRAL CWA AND KEEP SMALL CHANCE
FOR LINGERING -SHRA IN EAST FOR A FEW HOURS.
EXPECT LOW CLOUDS TO THIN ACROSS CENTRAL AND MOST OF EASTERN CWA
LATER THIS MRNG BUT MORE CLOUDS AND FOG MAY LINGER CLOSER TO THE
LAKE DUE TO LAKE BREEZE.
DESPITE WEAK SHEAR...DEWPOINTS IN THE 50S AND PARTIAL SUNSHINE
SHOULD RESULT IN MUCAPES INCREASING TO 300 TO 800 J THIS AFTN.
STRONGEST FORCING ASSOCIATED WITH UPPER LOW TO REMAIN TO THE SOUTH
OF THE IL BORDER THIS AFTN...HOWEVER WL STILL HAVE LOW PRESSURE TROF
MOVING THRU SRN WI. IN ADDITION...SRN CWA GETS GRAZED BY STRONGER
SYNOPTIC FORCING FROM LEFT EXIT REGION OF UPPER JET. HENCE EXPECT
SCT SHRA AND A FEW TSTRMS TO DEVELOP OVER CWA THIS AFTN INTO THE
EARLY EVE BEFORE DIMINISHING. BACK DOOR COLD FRONT WILL SWEEP
ACROSS CWA AFT MIDNIGHT USHERING COOLER AND DRIER AIR BACK INTO THE
REGION.
FRIDAY AND FRIDAY NIGHT - CONFIDENCE...MEDIUM
CONSIDERABLE DAVA TAKES HOLD WITH INCOMING MID LEVEL RIDGING IN
THE WAKE OF DEPARTED SHORTWAVE INTO THE OHIO VALLEY. LOW LEVEL
COLD ADVECTION WELL UNDERWAY IN THE WAKE OF THE THURSDAY NIGHT
COLD FRONT. LLVL RH PROGS AND MOS DATA SUGGEST SOME MORNING
CLOUDINESS HANGING ON BUT THINGS SCOUR OUT IN THE AFTERNOON. MAIN
CONCERN THEN SHIFTS TO FROST POTENTIAL FOR LATER FRIDAY NIGHT.
SURFACE HIGH RIDGES IN AND WINDS ARE PROGGD TO BECOME QUITE LIGHT.
925 TEMPS ARE SUPPORTIVE OF THE CHILLY 30S THAT MOS IS GENERATING
SO HAVE INTRODUCED FROST INTO THE GRIDS FOR LATER FRIDAY NIGHT.
WHERE TEMPS ARE COLDEST AT SOME OF THE INTERIOR SECTIONS OF THE
CWA HAVE WENT WITH AREAS OF FROST WITH PATCHY ELSEWHERE. MAY END
UP NEEDING AN ADVISORY BUT AT THIS TIME WILL MENTION IN HWO.
SATURDAY - CONFIDENCE...MEDIUM
SO AFTER A CHILLY START ANOTHER QUIET DAY IS IN STORE FOR SRN WI
WITH THE SURFACE RIDGE AXIS SHIFTING TO OUR EAST. THIS WILLS ET UP
A NICE RETURN AND 850/925 WAA. WARMUP WILL BE TEMPERED LAKESIDE AS
ONSHORE FLOW FROM THE SE WILL DOMINATE.
SATURDAY NIGHT THROUGH MONDAY NIGHT - CONFIDENCE...MEDIUM
AN UNSETTLED PATTERN IS EXPECTED WITH SURFACE WARM FRONT SETTING UP
ACROSS CNTRL OR SRN WI. LOW PRESSURE IN THE NRN PLAINS WILL BE
DRIVEN BY APPROACHING MID LEVEL WAVE AND INCREASING DCVA THERE. SO
SHRA/TSRA INITIALLY WILL BE DRIVEN BY THE LLJ INTERACTION WITH THE
SFC/850 FRONTS IN THE STATE. THE SURFACE LOW IS THEN EXPECTED TO
WORK EASTWARD ALONG THE SFC FRONT SUNDAY NIGHT INTO MONDAY WHICH
WILL SUPPORT MORE ROUNDS OF SHRA/TSRA. IN ADDITION THERE WILL BE
TIMES WHEN THE LEFT FRONT EXIT REGION OF THE UPPER JET WILL BE
SITUATED FAVORABLY ACROSS SRN WI FOR ENHANCED LIFT. THE GFS
CONTINUES TO BE THE FASTER SOLUTION EXITING THIS PRECIP EARLY MONDAY
EVENING WHILE THE ECMWF HANGS ONTO SOME PRECIP ALL OF MONDAY NIGHT.
TUESDAY - CONFIDENCE...LOW TO MEDIUM
DUE TO THE DIFFERING SPEEDS OF THIS SYSTEM THERE IS SOME TIMING
CONCERNS. THE GFS CONTINUES TO BE THE FASTEST SOLUTION WITH THE LOW
AND UPPER WAVE OFF TO OUR EAST WHILE THE ECMWF AND GEM SLOWER SPEED
SUGGESTS PRECIP COULD LINGER INTO TUESDAY MORNING. WILL GO WITH A
MORE PROGRESSIVE SOLUTION THAT THE GFS IS SHOWING AND THE SUPERBLEND
POPS TEND TO FAVOR THIS TREND. SO WILL GO DRY WITH A COOLER DAY AS
NORTHEAST WINDS AND SUBSIDENCE TAKE OVER DUE TO THE EXITING WAVE AND
LOW LEVEL CAA REGIME WITH INCOMING SFC HIGH.
WEDNESDAY - CONFIDENCE...MEDIUM
PATTERN REMAINS FAIRLY ACTIVE WITH ANOTHER 500 MILLIBAR WAVE RIDING
NORTHEAST INTO THE UPPER MIDWEST. A SURFACE LOW DEVELOPS FROM THE
DAKOTAS AND MINNESOTA WITH POTENTIAL FOR A STRONG SOUTHERLY WAA
REGIME AND 925 TEMPS POSSIBLY GETTING BACK INTO THE TEENS CELSIUS.
WILL GO WITH THE SUPERBLEND POPS FOR MORE SHRA/TSRA. WILL HAVE TO
KEEP AN EYE ON THIS ONE. SYSTEM HAS SOME PRETTY HIGH CWASP NUMBERS
..ATTM THESE HIGHEST NUMBERS ARE JUST TO OUR SOUTH. DECENT
DYNAMICS. LONG WAYS OFF BUT FOR THIS FAR OUT SOME GOOD CONSENSUS
BETWEEN THE ECMWF AND GFS. SUPERBLEND TEMPS MAY BE TOO COOL GIVEN
THE POTENTIAL WARM SIGNAL WITH THE 850/925 TEMPS.
AVIATION/12Z TAFS/...LIGHT ONSHORE FLOW WL CONTINUE TO PULL LAKE
INDUCED FOG INTO ERN TAF SITES INTO THE MORNING...AND MAY LINGER
AT KMKE THRU MUCH OF THE DAY. HOWEVER LOWEST VSBYS ARE EXPECTED
THIS MRNG. OTHERWISE IFR CIGS OVER TAF SITES SHOULD SLOWLY LIFT
THIS MRNG AND SHOULD TRANSITION TO VFR... HOWEVER CONFIDENCE LOW
IN EAST DUE TO LAKE BREEZE AND PERSISTENT ONSHORE FLOW. A BRIEF
T-STORM MAY AFFECT TAF SITES THIS AFTN OR EARLY EVE. BACK DOOR
COLD FRONT WILL RESULT IN ABRUPT WIND SHIFT AND GUSTY WINDS LATER
TNGT.
MARINE...MOIST LOW LEVEL AIR HAS SPREAD INTO THE SOUTHERN PORTION
OF THE NEARSHORE WATERS. KENOSHA WEBCAMS SHOW DENSE FOG AT THE SHORE
WHERE DEWPOINTS HAVE RISEN INTO THE LOWER 50S. DEWPOINTS REMAIN A
LITTLE LOWER FARTHER NORTH TOWARD SHEBOYGAN...HOWEVER WEBCAMS IN
THIS AREA ARE ALSO SHOWING LOWERING VSBYS. LAKE MI TEMPS REMAIN
MOSTLY IN THE LOWER 40S SO COOL WATER AND LIGHT WINDS ARE RESULTING
IN AREAS OF DENSE FOG. WINDS ARE EXPECTED TO REMAIN LIGHT SOUTH TO
SOUTHEAST TODAY AS WEAK LOW PRESSURE APPROACHES. HENCE EXPECT
AREAS OF DENSE FOG TO PERSIST AND WILL POST MARINE DENSE FOG ADVY
UNTIL 00Z FRI.
LOW PRESSURE WILL EXIT REGION OVERNIGHT. TIGHTENING PRESSURE
GRADIENT TO THE NORTH WILL PULL BACK DOOR COLD FRONT ACROSS NEAR
SHORE AREA FROM 05Z THROUGH 10Z TONIGHT. ABRUPT WIND SHIFT TO THE
NORTH TO NORTHEAST CAN BE EXPECTED WITH A RAPID INCREASE IN WIND
GUSTS. WIND GUSTS MAY APPROACH 30 KTS FOR SEVERAL HOURS. HENCE WL
POST SMALL CRAFT ADVISORY FOR LATE TONIGHT THROUGH FRIDAY DUE TO
LINGERING HIGH WAVES.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
SMALL CRAFT ADVISORY FROM 2 AM TO 10 PM CDT FRIDAY FOR LMZ645-
646.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 PM CDT FRIDAY
FOR LMZ643-644.
&&
$$
UPDATE...DDV/SPM
TODAY/TONIGHT AND AVIATION/MARINE...MBK
FRIDAY THROUGH WEDNESDAY...COLLAR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
619 AM CDT THU APR 21 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CDT THU APR 21 2016
MAIN FCST CONCERNS THIS PERIOD...LINGERING -SHRA TODAY/THIS
EVENING...CLOUD TRENDS/TEMPERATURES TODAY/TONIGHT.
WV/IR IMAGERY AND SFC OBS AT 06Z SHOWED A SFC THRU MID LEVEL LOW
SPINNING OVER WESTERN IA...MAKING VERY LITTLE PROGRESS EASTWARD
SINCE 00Z. WV IMAGERY SHOWED MID LEVEL DRYING HAD SPREAD NORTHWARD
ACROSS MUCH OF WI/EASTERN MN ON THE EAST SIDE OF THE LOW...CLEARING
THE BULK OF THE -SHRA OUT OF THE FCST AREA. THIS DRYING WORKING
THE LOWER CLOUDS AS WELL...WITH FOG-PRODUCT IMAGERY INDICATING
CLEAR TO PARTLY CLOUDY SKIES OVER THE SOUTHWEST HALF OF THE FCST
AREA...WITH THIS DECREASE OF CLOUDS SPREADING NORTHEAST EARLY THIS
MORNING. SOME FOG DEVELOPING IN THE AREAS WHERE SKIES HAD
CLEARED...AIDED BY LIGHT WINDS AND THE RECENT /BUT LIGHT/ RAINS.
MODEL RUNS OF 21.00Z INITIALIZED QUITE WELL. MODEL CONSENSUS HAS
TRENDED THE SLOWER/STRONGER/FURTHER SOUTH OF THE EARLIER RUNS AS THE
OLD MID LEVEL LOW TRACKS ACROSS SOUTHERN IA TODAY THEN ACROSS IL
TONIGHT. NOT AS SLOW/SOUTH AS THE 20.00Z CAN-GEM THOUGH. RATHER
TIGHT MODEL CONSENSUS THRU 12Z FRI HAS SHORT-TERM FCST CONFIDENCE ON
THE GOOD SIDE THIS CYCLE.
IN THE SHORT TERM...MODEL CONSENSUS TRENDS LEAD TO SOME NEEDED
ADJUSTMENTS TO THE FCST...ESPECIALLY WITH CLOUD TRENDS AND TIMING OF
-SHRA CHANCES TODAY/THIS EVENING. STRONGER SHORTWAVE AROUND THE EAST
SIDE OF THE MID LEVEL LOW WAS LIFTING NORTH OF THE FCST AREA EARLY
THIS MORNING WITH DRY SLOT/DRYING IN THE 800-500MB LAYER SEEN IN WV
IMAGERY EAST OF THE MID LEVEL LOW ROTATING ACROSS THE AREA. NEARLY
VERTICALLY STACKED SFC-500MB LOW OVER NOW HAS A LESS PW TO WORK WITH
AND A DRIER COLUMN AHEAD OF IT TO OVERCOME AS IT T MOVES EAST TODAY.
MUCH LIKE WED...BIGGER CHALLENGE TODAY WILL BE CLOUD TRENDS AS THE
DRY SLOT PIVOTS ACROSS THE AREA. APPEARS MUCH OF THE FCST AREA WILL
NOW SEE A PERIOD OF SUNSHINE THIS MORNING AND TRENDED BOTH CLOUDS/
SHRA CHANCES DOWN THIS MORNING. WITH THE DRIER AIR AHEAD OF IT AND
FURTHER SOUTH TRACK OF THE 500MB LOW/SHORTWAVE WITH IT...APPEARS
BULK OF THE SHRA WITH THAT PORTION OF THE SYSTEM WILL PASS SOUTH OF
THE FCST AREA THIS AFTERNOON AND REDUCED THOSE PRECIP CHANCES AS
WELL. SLOWER EASTWARD PROGRESS OF THE ENTIRE TROUGH NOW PIVOTS THE
DEFORMATION -SHRA BAND WRAPPED AROUND THE NORTHWEST SIDE OF THE
CIRCULATION INTO THE FCST AREA LATE THIS AFTERNOON/THIS EVENING.
WITH THE 700-500MB LOW OPENING UP THIS EVENING AS IT MOVES EAST OF
THE REGION...DEFORMATION BAND LOOSES MUCH OF ITS FORCING/MOISTURE
FEED AND QUICKLY DIMINISHES AFTER 03Z AT IT TRIES TO CROSS THE
FCST AREA. RAISED -SHRA CHANCES A BIT IN THE 00-03Z PERIOD THEN
THE QUICKLY DIMINISHING TREND OF -SHRA AFTER 03Z LOOKS GOOD.
OTHER CONCERN TONIGHT IS CLOUD CLEARING TREND. MODELS CLEAR OUT
THE MOISTURE AROUND/ABOVE 850MB AS NORTHWEST FLOW AND DEEPER
LAYERED SUBSIDENCE SPREAD IN BEHIND THE DEPARTING TROUGH. STRONGER
PRESSURE RISES BUILD IN LATER TONIGHT TOO...BUT RATHER CONSISTENT
SIGNAL AMONG MODELS FOR 925MB MOISTURE TO ROTATE SOUTH INTO THE
AREA TONIGHT. SOUNDINGS SHOWING THIS MOISTURE STUCK IN/UNDER A
RATHER STRONG INVERSION IN THE 925-875MB LAYER. WITH CLOUDS
UPSTREAM OVER WESTERN ONTARIO IN THIS MOISTURE FIELD...TRENDED
TOWARD SLOWER DECREASE/CLEARING OF THE CLOUDS TONIGHT. WITH SOME
SUNSHINE EXPECTED MOST LOCATIONS THIS MORNING...LEANED TOWARD
WARMER OF THE GUIDANCE HIGHS. CLEARING NORTH TO SOUTH LATER
TONIGHT WILL SET THE FCST AREA UP FOR A LARGER TEMP GRADIENT BY
FRI MORNING. FAVORED WARMER OF GUIDANCE LOWS ACROSS THE SOUTH END
OF THE FCST AREA AND BLEND OF THE LOWS ACROSS THE NORTH END. NORTH
GRADIENT WINDS/BOUNDARY LAYER MIXING SHOULD KEEP ANY
FROST/FREEZING TEMPS AT BAY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 408 AM CDT THU APR 21 2016
FOR FRIDAY THRU SATURDAY NIGHT...
MAIN FCST CONCERNS THIS PERIOD...COOL TEMPERATURES/PATCHY FROST
POSSIBILITIES FRI NIGHT...RETURNING -SHRA/ISOLATED TSRA CHANCES SAT
NIGHT.
21.00Z MODEL RUNS IN VERY GOOD AGREEMENT ON RISING HGTS/SHORTWAVE
RIDGING TO BUILD INTO THE UPPER MIDWEST FRI...WITH THIS RIDGING TO
THEN HOLD OVER THE REGION FRI NIGHT/SAT. MODELS CONTINUE TREND OF
WEAKENING THIS RIDGING OVER THE REGION SAT NIGHT...AHEAD OF THE NEXT
TROUGH/MID LEVEL LOW FROM THE WESTERN CONUS AS IT MOVE INTO THE
WY/CO/NEB/SD AREA. MUCH TIGHTER CONSENSUS ON THIS FEATURE THIS CYCLE
VS. THE 19.00Z/20.00Z RUNS. FCST CONFIDENCE IN THE FRI THRU SAT
NIGHT PERIOD IS GOOD THIS CYCLE.
WITH PROGRESSIVE FLOW AND RISING HGTS/SHORTWAVE RIDGING BUILDING IN
FRI...ANY REMAINING CLOUDS SHOULD EXIT RATHER QUICKLY FRI MORNING AS
THE SFC-850MB RIDGE AXIS AND ITS ANTI-CYCLONIC FLOW BUILDS
SOUTHEAST ACROSS THE REGION. 925MB TEMPS ONLY IN THE +7C TO +11C
RANGE AT 00Z SAT. EVEN WITH PLENTY OF SUNSHINE FRI...HIGHS FRI
LOOKING TO BE IN THE MID 50S-LOWER 60S MOST LOCATIONS. SFC RIDGE
AXIS IS STILL NEAR OVER THE FCST AREA FRI EVENING...WITH WINDS
EXPECTED TO DECOUPLE FOR A WHILE MOST LOCATIONS. GRADIENT REMAINS
QUITE WEAK OVER THE EAST SIDE OF THE FCST AREA THRU 12Z SAT...FOR
LIGHT/VARIABLE WINDS AND STRONGER RADIATIONAL COOLING. COOLER
AIRMASS...925MB TEMPS +3C TO +6C...REMAINS OVER THE EAST HALF OF
THE FCST AREA FRI NIGHT WHILE WARM ADVECTION AND SOME SOUTHEAST
GRADIENT WINDS SPREAD OVER THE WEST HALF OF THE FCST AREA. TEMPS
ACROSS THE EAST SIDE OF THE FCST AREA LOOKING TO DROP INTO THE MID
30S LATE FRI NIGHT AND ADDED PATCHY/AREAS OF FROST TO THE GRIDS IN
THE USUAL COLDER LOW-LAYING LOCATIONS IN THE 06Z-14Z SAT PERIOD.
MAY YET NEED A FROST ADVISORY FOR JACKSON/MONROE/ADAMS/JUNEAU
COUNTIES LATE FRI NIGHT INTO EARLY SAT MORNING. SOUTHERLY
FLOW/WARM ADVECTION SPREAD ACROSS THE AREA SAT AS LOW PRESSURE/MID
LEVEL TROUGHING START TO MOVE INTO THE PLAINS. 925MB TEMPS BY SAT
AFTERNOON SUPPORTING HIGHS IN THE 60S TO NEAR 70...FOR WHAT SHOULD
BE A RATHER NICE WEATHER DAY ON THE FRONT HALF OF THE WEEKEND.
FIRST MOISTURE AHEAD OF THE PLAINS SYSTEM ARRIVES SAT NIGHT...WITH
THE NOSE OF THE LOW LEVEL JET/MOISTURE TRANSPORT BEING LIFTED OVER A
FRONTAL BOUNDARY PROGGED TO SAG SLOWLY SOUTH THRU THE REGION. RATHER
TIGHT MODEL CONSENSUS FOR THIS BOUNDARY TO LIE ACROSS SOUTHERN MN TO
NEAR KGRB AT 12Z SUN. PW VALUES INCREASE INTO THE 1+ INCH RANGE BY
12Z SUN. MODELS RATHER CONSISTENT IN DEVELOPING PRECIP NEAR/NORTH OF
THE FRONTAL BOUNDARY...ESPECIALLY LATER SAT NIGHT. CARRIED 20-50
PERCENT SHRA CHANCES SAT EVENING...MAINLY OVER THE NORTHEAST 1/2 OF
THE FCST AREA...RAISING TO 40-60 PERCENT AFTER MIDNIGHT. LESSER
CHANCES ACROSS THE SOUTH PORTIONS OF THE FCST AREA SAT NIGHT...
SOUTH OF THE FRONT. SMALL TSRA CHANCE WEST OF THE MS RIVER LATER SAT
NIGHT REASONABLE AS IMPROVING MODEL SIGNAL FOR MUCAPE TO INCREASE
INTO THE 250-500 J/KG RANGE AS THE COLUMN BECOMES INCREASINGLY MOIST.
FAVORED WARMER OF GUIDANCE HIGHS FRI...COOLER OF GUIDANCE LOWS FRI
NIGHT THEN A BLEND OF THE GUIDANCE HIGHS/LOWS FOR SAT/SAT NIGHT.
FOR SUNDAY THRU WEDNESDAY...DAYS 4 TO 7...
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES MUCH OF THE
PERIOD.
MEDIUM RANGE MODEL RUNS OF 21.00Z OFFER A TIGHTENING CONSENSUS FOR
THE CO/WY/NEB/SD LOW/TROUGH TO MOVE SLOWLY EAST SUN ACROSS THE
PLAINS SUN/SUN NIGHT...THEN ACROSS THE UPPER MIDWEST MON/MON NIGHT.
IMPROVING SIGNAL FOR SHORTWAVE RIDGING TO BUILD ACROSS THE UPPER
MIDWEST TUE...WITH THE NEXT STRONGER TROUGH/ENERGY APPROACHING/
MOVING INTO THE UPPER MIDWEST WED. WITH BETTER MODEL AGREEMENT ALL
THE WAY THRU WED...FCST CONFIDENCE IN THE DAY 4-7 PERIOD IS AVERAGE
THIS CYCLE.
TIGHTER MODEL CONSENSUS CONTINUES TO SAG THE FRONTAL BOUNDARY SLOWLY
SOUTH ACROSS THE FCST AREA SUN/SUN NIGHT...THIS AS THE SFC LOW MOVE
EAST/SOUTHEAST ALONG IT. SOME MODEL DETAIL DIFFERENCES ON THE SPEED
OF THE LOW MOVING EAST...BUT BIGGER PICTURE IS BROAD FORCING/ASCENT
ACROSS THE AREA THESE PERIODS AHEAD OF THE APPROACHING SFC-500MB
LOW. CONSENSUS SHRA CHANCES IN TOE 40-70 PERCENT RANGE SUN/SUN NIGHT
LOOKING GOOD FOR NOW...WITH POTENTIAL FOR SOME 1 TO 2 INCH RAINFALL
TOTALS FROM 12Z SUN TO 12Z MON. MUCAPE SUN/SUN NIGHT GENERALLY
PROGGED TO BE IN THE 250-500 J/KG RANGE. THIS ALONG WITH THE BROAD
FORCING/ASCENT...ACCOUNTS FOR THE ISOLATED-SCT TSRA MENTION ACROSS
MOST OF THE FCST AREA THESE PERIODS. MAIN TROUGH PROGGED TO WEAKEN
AS IT PASSES MON/MON NIGHT WITH THE FRONT BEING PUSHED FURTHER SOUTH
OF THE FCST AREA. DECREASING MAINLY SHRA CHANCES MON/MON NIGHT
LOOKING WELL TRENDED...AS DO COOLER TEMPS AS NORTH/NORTHEAST FLOW
AND LOW LEVEL COLD ADVECTION SPREADS ACROSS THE AREA. TUE TRENDING
TO BE THE DRY DAY AS THE MID LEVEL SHORTWAVE RIDGING AND SFC HIGH
PRESSURE BUILD ACROSS THE REGION. THE DRYNESS NEXT WEEK APPEARS
SHORT LIVED AS THE NEXT SFC-MID LEVEL LOW WITH ITS ROUND OF MOISTURE
INCREASE...LOWER LEVEL THERMO-DYNAMIC FORCING AND DIVERGENCE ALOFT
APPROACHES/SPREADS INTO THE REGION TUE NIGHT/WED. SHRA/TSRA CHANCES
INCREASING INTO THE 30-50 PERCENT RANGE BY WED REASONABLE AT THIS
TIME. GIVEN SOME MODEL DETAIL VARIABILITY FOR SUN-WED...MODEL/
ENSEMBLE CONSENSUS OF HIGHS/LOWS THRU THIS PERIOD LOOKING WELL
TRENDED AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 619 AM CDT THU APR 21 2016
THE DENSE FOG THAT FORMED OVERNIGHT IS ALREADY STARTING TO
DISSIPATE AS A MID LEVEL CLOUD DECK MOVES IN FROM THE SOUTH.
EXPECTING THAT THIS WILL BE PRETTY MUCH GONE AT BOTH SITES BY
14Z...BUT KRST WILL START OUT MUCH LOWER THAN KLSE AS THE CLOUDS
HAVE YET TO MOVE IN. AS THE SURFACE LOW OVER WESTERN IOWA MOVES
EAST TODAY...EXPECT TO SEE THE BAND OF LOWER CLOUDS OVER SOUTHWEST
AND CENTRAL MINNESOTA MOVE INTO THE AREA. BOTH THE 21.06Z AND
21.09Z RAP WOULD SUGGEST THESE WILL COME IN AS A LOW VFR DECK.
THERE COULD BE SOME SHOWERS WITH THESE CLOUDS AS WELL...BUT
THE HI-RES MODELS SUGGEST ANY SHOWERS WOULD BE VERY LATE THIS
AFTERNOON. CONFIDENCE THAT THE FORCING WILL BE STRONG ENOUGH TO
STILL BE PRODUCING SHOWERS IS NOT VERY HIGH SO WILL LET LATER
FORECAST ADD A VCSH IF NEEDED. AS THE WINDS COME AROUND TO THE
NORTHWEST THE LOWER CLOUDS OVER NORTHWEST MINNESOTA AND SOUTHWEST
ONTARIO SHOULD COME DOWN OVERNIGHT TO PRODUCE A MVFR CEILING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
225 PM EDT THU APR 21 2016
.SYNOPSIS...
SURFACE HIGH PRESSURE OFF THE COAST WITH A MOIST SOUTHERLY FLOW
ACROSS THE REGION TODAY. AN APPROACHING COLD FRONT WILL CROSS THE
AREA FRIDAY NIGHT. SHOWERS AND THUNDERSTORMS EXPECTED AHEAD OF THE
FRONT ON FRIDAY. DRY HIGH PRESSURE WILL BUILD INTO THE REGION
LATE SATURDAY THROUGH TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE UPPER RIDGE WILL SHIFT OFF THE EAST COAST THIS AFTERNOON
CREATING A MORE S/SW FLOW REGIME AND MODERATE WARM ADVECTION
ACROSS THE REGION. SKIES WILL BE PARTLY CLOUDY THIS AFTERNOON
WITH HIGHS IN THE LOW TO MID 80S.
HIGH RESOLUTION MODELS SHOW A SEA BREEZE BOUNDARY MOVING INLAND
LATE THIS AFTERNOON/EVENING. MID LEVEL DRY AIR AND A SMALL
CAPPING INVERSION WILL LIMIT CONVECTIVE DEVELOPMENT. HRRR MODEL
RUNS INDICATE SCATTERED TO ISOLATED SHOWERS DEVELOPING ALONG THE
COAST.
CLOSED UPPER LOW WILL CONTINUE TRACKING EASTWARD TOWARDS THE
REGION OVERNIGHT WITH A COLD FRONT MOVING EAST OF THE MISSISSIPPI
RIVER. THIS PUTS THE REGION IN THE WARM SECTOR OF THE NEXT SYSTEM.
LOW-LEVEL FLOW OVERNIGHT WILL BE OUT OF THE SOUTH TO SOUTHWEST...
ALLOWING FOR AN INCREASE IN MOISTURE. DO EXPECT THE EARLY PART OF
TONIGHT TO BE DRY...THEN SHOULD SEE AN INCREASE IN POPS FROM WEST
TO EAST AFTER MIDNIGHT. MILD TEMPERATURES TONIGHT WITH LOWS MAINLY
IN THE LOWER 60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
MOST PLACES LOOK TO GET WET ON FRIDAY AS A MODERATE STRENGTH UPPER
TROF AND ASSOCIATED COLD FRONT APPROACHES FROM THE WEST. DEEP
MOISTURE FLOW AHEAD OF THE SYSTEM SHOULD RAISE PWS TO AROUND 1.5
INCHES ACROSS THE CWA...AND DECENT LIFT DUE TO DIFFERENTIAL
VORTICITY ADVECTION IN MID LEVELS AND UPPER LEVEL JET DIVERGENCE
WILL PRODUCE WIDESPREAD SHOWERS WITH A FEW THUNDERSTORMS. THERE
WILL BE SOME MODEST LOW LEVEL CAPE WITH VALUES POTENTIALLY AS HIGH
AS 1000 J/KG...BUT DEEP LAYERED SHEAR IS NOT TOO IMPRESSIVE...SO
THE THREAT FOR SEVERE WEATHER LOOKS LOW. QPF WILL GENERALLY BE 1/2
INCH OR LESS...BUT PLACES THAT DO SEE SOME
THUNDERSTORMS...ESPECIALLY IN THE SOUTHEASTERN THIRD OF THE
CWA...COULD GET LOCALLY UP TO AN INCH. TEMPS SHOULD BE SEASONABLY
WARM IN THE UPPER 70S DESPITE CLOUD COVER AS THERE WILL BE LOW
LEVEL WARM ADVECTION AHEAD OF THE COLD FRONT.
FRIDAY NIGHT...THE BEST OF THE UPPER SUPPORT SHOULD MOVE THROUGH
QUICKLY...AS WILL THE COLD FRONT. SHOWERS WILL END FROM WEST TO
EAST DURING THE EVENING...WITH JUST A FEW LINGERING IN THE
SOUTHEAST AFTER MIDNIGHT. TEMPS WILL DROP DOWN INTO THE UPPER
50S...NOT PARTICULARLY COOL AS CLOUDS WILL NOT CLEAR UNTIL LATE
AND WINDS WILL REMAIN UP.
SATURDAY SHOULD BE MOSTLY DRY AS THE FRONT MOVES OFFSHORE. I CANT
RULE OUT A SHOWER IN THE NORTHEAST AS ANOTHER SPOKE OF ENERGY
DROPS INTO NORTH CAROLINA...BUT CHANCES LOOK TOO LOW AT THIS TIME
TO MENTION IN THE FORECAST. TEMPS WILL BE SEASONABLE WITH MID 70S
NORTH TO NEAR 80 IN THE CSRA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A SURFACE AREA OF HIGH PRESSURE WILL MOVE INTO THE SOUTHEAST FROM
SUNDAY INTO TUESDAY...KEEPING THE CWA DRY. THE AIR MASS WILL WARM
UP UNDER SUN ANGLE EQUIVALENT TO LATE AUGUST...WITH MAX TEMPS IN
THE LOWER TO MID 80S ON SUNDAY TO THE UPPER 80S TO NEAR 90 ON
TUESDAY. A COLD FRONT WILL APPROACH THE AREA FROM THE NORTH ON
WEDNESDAY...BUT IT IS TOO EARLY TO TELL IF IT WILL STALL JUST
NORTH OF THE CWA OR MAKE IT INTO THE CWA. MOST OF THE MID AND
UPPER LEVEL JET ENERGY WILL STAY TO THE NORTH IN EITHER CASE...BUT
A CLOSER FRONT COULD MEAN A BETTER CHANCE OF DIURNAL CONVECTION
WITH MAX TEMPS WELL UP INTO THE 80S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THIS EVENING.
SOUTHERLY FLOW ACROSS THE REGION BETWEEN HIGH PRESSURE OFF THE
COAST AND APPROACHING COLD FRONT WILL BRING INCREASING MOISTURE TO
THE REGION. VFR THIS AFTERNOON AND EVENING WITH CLOUDS BASES AT OR
ABOVE 5000 FEET. MVFR/IFR CIGS FORECAST TO DEVELOP 06Z-13Z WITH
INCREASING LOW LEVEL MOISTURE UNDER NOCTURNAL INVERSION. SCATTERED
SHOWERS EXPECTED TO DEVELOP AFTER 06Z IN WEAKLY UNSTABLE AIRMASS.
CONVECTION SHOULD INCREASE IN COVERAGE AND INTENSITY FRIDAY AFTERNOON.
LOW LEVEL WIND SHEAR POSSIBLE 04Z-12Z AS A LOW LEVEL JET DEVELOPS
OVER THE REGION. HAVE NOT INCLUDED LOW LEVEL WIND SHEAR IN TAFS AT
TIME GIVEN LOW CONFIDENCE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE FRIDAY INTO
FRIDAY EVENING FROM LOW CLOUDS/SHOWERS/ISOLATED THUNDERSTORMS
AHEAD OF THE FRONT. CONDITIONS WILL IMPROVE BY SATURDAY...WITH VFR
EXPECTED INTO EARLY NEXT WEEK.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
201 PM EDT THU APR 21 2016
.SYNOPSIS...
SURFACE HIGH PRESSURE OFF THE COAST WITH A MOIST SOUTHERLY FLOW
ACROSS THE REGION TODAY. AN APPROACHING COLD FRONT WILL CROSS THE
AREA FRIDAY NIGHT. SHOWERS AND THUNDERSTORMS EXPECTED AHEAD OF THE
FRONT ON FRIDAY. DRY HIGH PRESSURE WILL BUILD INTO THE REGION
LATE SATURDAY THROUGH TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE UPPER RIDGE WILL SHIFT OFF THE EAST COAST THIS AFTERNOON
CREATING A MORE S/SW FLOW REGIME AND MODERATE WARM ADVECTION
ACROSS THE REGION. SKIES WILL BE PARTLY CLOUDY THIS AFTERNOON
WITH HIGHS IN THE LOW TO MID 80S.
HIGH RESOLUTION MODELS SHOW A SEA BREEZE BOUNDARY MOVING INLAND
LATE THIS AFTERNOON/EVENING. MID LEVEL DRY AIR AND A SMALL
CAPPING INVERSION WILL LIMIT CONVECTIVE DEVELOPMENT. HRRR MODEL
RUNS INDICATE SCATTERED TO ISOLATED SHOWERS DEVELOPING ALONG THE
COAST.
CLOSED UPPER LOW WILL CONTINUE TRACKING EASTWARD TOWARDS THE
REGION OVERNIGHT WITH A COLD FRONT MOVING EAST OF THE MISSISSIPPI
RIVER. THIS PUTS THE REGION IN THE WARM SECTOR OF THE NEXT SYSTEM.
LOW-LEVEL FLOW OVERNIGHT WILL BE OUT OF THE SOUTH TO SOUTHWEST...
ALLOWING FOR AN INCREASE IN MOISTURE. DO EXPECT THE EARLY PART OF
TONIGHT TO BE DRY...THEN SHOULD SEE AN INCREASE IN POPS FROM WEST
TO EAST AFTER MIDNIGHT. MILD TEMPERATURES TONIGHT WITH LOWS MAINLY
IN THE LOWER 60S.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
UPPER TROUGH MOVING THROUGH THE EASTERN CONUS ON FRIDAY WILL
DRIVE COLD FRONT TOWARD THE REGION THROUGH THE DAY. EXPECT MAINLY
SHOWERS EARLY IN THE DAY FRIDAY...WITH POTENTIAL FOR ISOLATED
THUNDERSTORMS IN THE AFTERNOON AS THE AIR MASS BECOMES WEAKLY TO
MODERATELY UNSTABLE. STRONGER CONVECTION MORE LIKELY WEST OF THE
REGION BACK IN NORTHWEST GEORGIA. DECREASING POPS THROUGH THE
NIGHT FRIDAY INTO SATURDAY MORNING AS FRONT MOVES THROUGH THE
AREA. DRY CONDITIONS ONCE AGAIN FOR SATURDAY. GUIDANCE
TEMPERATURES THROUGH THE PERIOD SEEM REASONABLE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE TO SETTLE INTO THE CWA FROM SATURDAY THROUGH
MONDAY. MOISTURE INCREASE MID WEEK AND ANOTHER FRONT POSSIBLY
MOVING SOUTH FROM THE NORTH MAY LEAD TO ISOLATED OR SCATTERED
AFTERNOON SHOWERS TUESDAY AND WEDNESDAY. TEMPERATURES SHOULD BE AT
OR ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH MONDAY/...
HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THIS EVENING.
SOUTHERLY FLOW ACROSS THE REGION BETWEEN HIGH PRESSURE OFF THE
COAST AND APPROACHING COLD FRONT WILL BRING INCREASING MOISTURE TO
THE REGION. VFR THIS AFTERNOON AND EVENING WITH CLOUDS BASES AT OR
ABOVE 5000 FEET. MVFR/IFR CIGS FORECAST TO DEVELOP 06Z-13Z WITH
INCREASING LOW LEVEL MOISTURE UNDER NOCTURNAL INVERSION. SCATTERED
SHOWERS EXPECTED TO DEVELOP AFTER 06Z IN WEAKLY UNSTABLE AIRMASS.
CONVECTION SHOULD INCREASE IN COVERAGE AND INTENSITY FRIDAY AFTERNOON.
LOW LEVEL WIND SHEAR POSSIBLE 04Z-12Z AS A LOW LEVEL JET DEVELOPS
OVER THE REGION. HAVE NOT INCLUDED LOW LEVEL WIND SHEAR IN TAFS AT
TIME GIVEN LOW CONFIDENCE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE FRIDAY AFTERNOON
THROUGH EARLY SATURDAY AS A COLD FRONT CROSSES THE REGION.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
345 PM EDT THU APR 21 2016
.SYNOPSIS...
ISSUED AT 334 PM EDT THU APR 21 2016
SHOWERS AND A FEW THUNDERSTORMS WILL IMPACT THE REGION INTO
TONIGHT. SEVERE WEATHER IS NOT EXPECTED AT THIS TIME...BUT THE
STRONGEST STORMS COULD PRODUCE SMALL HAIL. RAIN CHANCES WILL
LINGER INTO FRIDAY MAINLY ALONG AND SOUTHEAST OF INTERSTATE 69.
LOWS TONIGHT IN THE MID 40S TO MID 50S.HIGHS ON FRIDAY WILL
GENERALLY BE IN THE UPPER 50S TO MIDDLE 60S AWAY FROM LAKE
MICHIGAN...WITH COOL ONSHORE FLOW LEADING TO HIGHS ONLY AROUND 50.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 334 PM EDT THU APR 21 2016
MAIN FOCUS ON CONVECTIVE DEVELOPMENT IN FAR WESTERN PARTS OF
FORECAST AREA AS WELL AS UPSTREAM NEAR THE UPPER LOW.
SOME POCKETS OF CLEARING/BREAKS HAVE OCCURRED ALLOWING TEMPERATURES
TO CLIMB INTO THE 60S ACROSS THE AREA AND MAKING A RUN AT 70 IN
WEST/SW LOCATIONS. NARROW PLUME OF HIGHER DEWPOINTS WAS NOW SHIFTING
ACROSS THE FORECAST AREA WITH SLIGHTLY LOWER READINGS UNDER THE
CLEARING AND WHERE CONVECTION WAS ATTEMPTING TO POP. ISOLATED
SHOWERS/STORMS HAVE BEEN DEVELOPING OVER THE LAST 30 TO 60
MINUTES...LIKELY CONTAINING AT LEAST SOME SMALL HAIL. ARC OF STORMS
ONGOING CLOSER TO THE UPPER LOW FROM WATERLOO IOWA TO MOLINE TO WEST
OF SPRINGFIELD IL. HRRR SUGGESTS THIS ACTIVITY WILL MOVE SLOWLY
NORTHEAST AND EXPAND MORE IN THE 22 TO 02Z WINDOW. HAVE KEPT HIGH
SCT TO NUMEROUS SHOWERS WITH MENTION OF THUNDER THROUGH THE EVENING.
EVE SHIFT MAY NEED TO ADJUST FOR TRENDS. TEMPERATURES WILL SLOWLY
FALL THIS EVENING AS AREA REMAINS IN THE WARM SECTOR...WITH SLOW
FALL OVERNIGHT AS THE COLD FRONT APPROACHES.
UPPER LOW WILL CONTINUE TO OPEN AND LINGER FRIDAY...ONLY DRIFTING
SLOWLY EAST INTO SOUTHERN OHIO BY 00Z SAT. GIVEN UPSTREAM TRENDS
UNDER THE UPPER LOW WITH SCATTERED SHOWERS AROUND...SEE NO REASON TO
MAKE ANY MAJOR CHANGES TO SE HALF OF THE AREA INTO MID AFTERNOON
WITH SCATTERED SHOWERS. WHILE NOT INTRODUCED...MAY NEED TO ADD
PASSING MENTION OF THUNDER AS SFC CAPE INCREASES TO AROUND 500 J/KG
AND MARGINAL LAPSE RATES.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 334 PM EDT THU APR 21 2016
A MORE PROGRESSIVE FLOW PATTERN WILL TAKE HOLD ON THE LOWER 48 THIS
WEEKEND INTO NEXT WEEK AS A SERIES OF WESTERN CONUS SHORTWAVES
EJECT/SHEAR EAST INTO MORE CONFLUENT/WNW FLOW OVER THE GREAT LAKES
REGION. LUCKILY THE WEEKEND WILL FEATURE DRY CONDITIONS WITH HIGH
PRESSURE IN CONTROL IN BETWEEN WAVES. SATURDAY THE COOLER/SUNNIER
DAY UNDER HIGH PRESSURE WITH WARM ADVECTION BEHIND SFC HIGH ALLOWING
HIGHS TO RETURN INTO THE 70S BY SUNDAY. FRONTAL SYSTEMS WITH THE
AFOREMENTIONED SHORTWAVES THEN BRING MORE UNSETTLED WX NEXT
WEEK...WITH LATEST GUIDANCE FAVORING MONDAY/MONDAY NIGHT AND
WEDNESDAY/WEDNESDAY NIGHT FOR HIGHER POPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1202 PM EDT THU APR 21 2016
LOWER CLOUDS SHOULD QUICKLY LIFT/DISSIPATE AS DENSER OVERCAST
SHIFTS EAST. VIS SATELLITE SHOWS MORE OF A CELLULAR NATURE TO
CLOUD COVER WITH SCT TO BKN COVERAGE OF CU EXPECTED THROUGH THE
AFTERNOON. WHILE BOTH SITES ARE SEEING A GENERAL LULL
NOW...SHOWERS AND POSSIBLY A FEW THUNDERSTORMS WILL APPROACH/ENTER
THE AIRSPACE OF EACH AIRPORT MAINLY AFTER 20Z. WILL LIKELY LEAVE
ANY MENTION OF THUNDER OUT UNLESS CLEAR SIGNALS BEGIN TO SHOW IN
ABOUT AN HOUR WHEN THE TAFS ARE ISSUED. ACTIVITY WILL CONTINUE
INTO THIS EVENING UNTIL THE LOW AND MAIN COLD FRONT SHIFT EAST
LATE TONIGHT INTO FRIDAY. AT LEAST A PERIOD OF IFR CONDITIONS
STILL LOOKS LIKELY NEAR/AFTER 12Z AS THE UPPER LEVEL SYSTEM MOVES
OVERHEAD AND WILL BE SLOW TO LEAVE...ESPECIALLY AT KFWA.
&&
.MARINE...
WEBCAMS SHOWING A GOOD DEAL OF DENSE FOG IN THE NEARSHORE WATERS
WARRANTING ISSUANCE OF A MARINE DENSE FOG ADVISORY INTO THIS
EVENING UNTIL COLDER AIR STARTS TO MOVE IN. WILL ALSO HOIST SMALL
CRAFT ADVISORY FOR FRIDAY INTO FRIDAY EVENING FOR INCREASING NW
FLOW AND HIGHER WAVES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...DENSE FOG ADVISORY UNTIL 2 AM EDT FRIDAY FOR LMZ043-046.
SMALL CRAFT ADVISORY FROM 8 AM FRIDAY TO 2 AM EDT SATURDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...STEINWEDEL
AVIATION...FISHER
MARINE...FISHER
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1219 PM EDT THU APR 21 2016
.SYNOPSIS...
ISSUED AT 1219 PM EDT THU APR 21 2016
SHOWERS AND A FEW THUNDERSTORMS WILL IMPACT THE REGION INTO
TONIGHT. SEVERE WEATHER IS NOT EXPECTED AT THIS TIME...BUT THE
STRONGEST STORMS COULD PRODUCE SMALL HAIL. HIGHS TODAY WILL REACH
THE UPPER 60S TO LOWER 70S...WARMEST CLOSER TO THE ILLINOIS STATE
LINE WHERE MORE SUNSHINE IS LIKELY TO OCCUR. RAIN CHANCES WILL
CONTINUE INTO TONIGHT WITH LOWS IN THE UPPER 40S TO LOW 50S.
&&
.UPDATE...
ISSUED AT 1202 PM EDT THU APR 21 2016
UPDATED GRIDS COMING SHORTLY TO LOWER POPS EAST FOR THE NEXT
SEVERAL HOURS AS MAIN AREA OF PRECIPITATION NOW MOVING AWAY WITH
MORE SHOWERY ACTIVITY EXPECTED INTO MID AFTERNOON.
VIS SAT SHOWING BREAKS OCCURRING IN DRY SLOT OF THE SYSTEM WITH
TEMPERATURES AND DEWPOINTS INCREASING (PUSHING NEAR 60 DEWPOINTS
NOW IN FAR SW). HRRR GENERALLY ON TRACK WITH STEADY RAINFALL
MOVING AWAY AND A FEW HOUR LULL WITH LITTLE MORE THAN SOME WIDELY
SCATTERED SHOWERS THROUGH ABOUT 20Z. AS PEAK HEATING
OCCURS...SHORTWAVE ARRIVES WITH DECREASING UPPER LEVEL
TEMPERATURES SHOULD SEE AN UPTICK IN COVERAGE AND INTENSITY WITH
WIDELY SCATTERED THUNDERSTORMS DEVELOPING. WIND FIELDS PRETTY
PATHETIC BUT LOW LEVEL LAPSE RATES INCREASE SUFFICIENTLY TO HELP
GET THINGS GOING...BUT CELLS LIKELY TO COLLAPSE FAIRLY QUICK.
ISOLATED STRONGER STORMS WOULD BE CAPABLE OF MARGINALLY SEVERE
HAIL IF THEY CAN PERSIST LONG ENOUGH AND IN THE DISSIPATION STAGE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM EDT THU APR 21 2016
INCREASING S/SW LLJ AHEAD OF APPROACHING CLOSED LOW SUPPORTING A
HEALTHY SWATH OF 295-300K SYSTEM RELATIVE ISENTROPIC ASCENT AND
MOISTURE ADVECTION EARLY THIS MORNING. DRY ANTECEDENT AIRMASS HAS
NOW BEEN LARGELY DISPLACED WITH 300K MIXING RATIOS CLIMBING TO
AROUND 7 G/KG AND PW VALUES APPROACHING 1.3 INCHES. LOW LEVEL
CONFLUENCE ZONE WILL MAKE SLOW EASTWARD PROGRESS LATER THIS MORNING
AS IT BECOMES ORIENTED PARALLEL TO MEAN FLOW ALOFT. CONTINUAL MOIST
ISENTROPIC ASCENT IN REGION OF GOOD UPPER DIVERGENCE AND AT LEAST
NEUTRAL STATIC STABILITY WILL MAINTAIN SCT/NUM SHOWERS FOR MUCH OF
THE DAY...ESPECIALLY IN OUR SOUTHEAST HALF. HI-RES MODELS SUGGEST
PARTIAL CLEARING IN OUR NORTHWEST HALF LATER THIS MORNING BUT THAT
WILL BE RELATIVELY SHORT LIVED GIVEN APPROACH OF VIGOROUS MIDLEVEL
CYCLONIC VORTICITY BULLSEYE BY THIS EVENING AND EXPECTATION FOR AT
LEAST SOME MARGINAL DIURNAL DESTABILIZATION. SOME THUNDERSTORMS
EXPECTED THIS AFTERNOON AND EVENING BUT INSTABILITY VALUES APPEAR
MEAGER AT THIS POINT. 00Z NAM SUGGESTS AROUND 1000 J/KG SBCAPE IN
OUR WEST THIS AFTERNOON BUT THIS IS LIKELY A BIT OVERDONE AND PREFER
MORE SUBDUED GFS VALUES WITH AROUND 500 J/KG. GIVEN POOR MIDLEVEL
LAPSE RATES AND LACK OF ANY SUBSTANTIVE LOW LEVEL FLOW THIS
AFTERNOON...SEVERE CHANCES APPEAR VERY LOW...ESPECIALLY EAST OF US-
31. BETTER LAPSE RATES BY LATE EVENING AS MIDLEVEL COLD POOL MOVES
OVERHEAD BUT ANY CONVECTION WILL LIKELY BE ELEVATED BY THEN GIVEN
LOSS OF DIURNAL HEATING. A FEW STRONGER STORMS MAY CLIP OUR FAR
WESTERN COUNTIES UNDER/NEAR SWODY1 MARGINAL RISK THIS EVENING BUT
AGAIN...CHANCES FOR EVEN THAT APPEAR LOW AT THIS POINT. REGARDLESS
OF INSTABILITY...CVA BULLSEYE WILL BRING A SECONDARY ROUND OF
SHOWERS TO THE AREA LATE THIS EVENING AND HAVE MAINTAINED LIKELY
POPS FOR MOST OF THE AREA DURING THAT TIME. HIGHS TODAY AROUND 70F
WITH LOWS TONIGHT GENERALLY IN THE UPPER 40S TO LOW 50S.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU APR 21 2016
MORE OF A PROGRESSIVE PATTERN IN THE LONG TERM PERIOD. UPPER LOW
THAT HAS PLAGUED THE CENTRAL CONUS WILL FINALLY BE OPENING UP AND
EXITING THE AREA AT THE START OF THIS PERIOD. MODELS HAVE SLOWED
THIS FEATURE AND MOISTURE NOW LINGERS FRIDAY OVER EASTERN THIRD OF
FORECAST AREA INTO THE AFTERNOON HOURS. PRETTY DECENT MODEL
AGREEMENT AND WITH MAIN TROUGH AXIS OVER TOP FRIDAY MORNING HAVE
RAISED POPS IN THE EAST TO HIGH CHANCE. MOST GUIDANCE MUCH HIGHER
AND HAVE TRENDED GRIDS UPWARD.
ANOTHER NICE WEEKEND SHAPING UP. CLOUDS TO SLOWLY CLEAR LATER FRIDAY
WITH MOSTLY CLEAR CONDITIONS FRIDAY NIGHT INTO SATURDAY AS HIGH
PRESSURE MOVES BY TO OUR NORTH. A FEW MODELS STILL WANT TO BRING
SOME LIGHT PCPN INTO THE FAR NORTH SUNDAY ON SOUTHERN FRINGE OF
DEVELOPING WARM FRONT. MAINTAINED A SLIGHT CHANCE POP BUT BEST
MOISTURE AND FORCING NORTH OF THE AREA AND MORE THAN LIKELY WILL
ONLY SEE INCREASED CLOUDS AND MAYBE A STRAY SHOWER IN AFTERNOON.
BETTER CHANCES FOR PCPN LOOK TO BE ON MONDAY AS MID LEVEL HEIGHTS
FALL WITH APPROACH OF SHORT WAVE AND SFC BOUNDARY SINKS FURTHER
SOUTH OVER THE AREA. AREA OF LOW PRESSURE TO TRACK ALONG BOUNDARY
ENHANCING ASCENT AND PCPN COVERAGE. DRYING LIKELY ON TUESDAY WITH
ANOTHER HIGH SLIDING ACROSS THE LAKES REGION. RETURN FLOW QUICKLY
DEVELOPS WITH PCPN CHANCES INCREASING AGAIN WEDNESDAY. MODEL
DISPARITY IN THESE LATER PERIODS WITH DEGREE OF WARM ADVECTION AND
SFC TEMPS. GFS MUCH WARMER THAN ECMWF AND OTHER MEDIUM RANGE
GUIDANCE. SUPERBLEND REMAINS IN THE MIDDLE TO COOLER SIDE AND
SIMILAR TO WPC GUIDANCE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1202 PM EDT THU APR 21 2016
LOWER CLOUDS SHOULD QUICKLY LIFT/DISSIPATE AS DENSER OVERCAST
SHIFTS EAST. VIS SATELLITE SHOWS MORE OF A CELLULAR NATURE TO
CLOUD COVER WITH SCT TO BKN COVERAGE OF CU EXPECTED THROUGH THE
AFTERNOON. WHILE BOTH SITES ARE SEEING A GENERAL LULL
NOW...SHOWERS AND POSSIBLY A FEW THUNDERSTORMS WILL APPROACH/ENTER
THE AIRSPACE OF EACH AIRPORT MAINLY AFTER 20Z. WILL LIKELY LEAVE
ANY MENTION OF THUNDER OUT UNLESS CLEAR SIGNALS BEGIN TO SHOW IN
ABOUT AN HOUR WHEN THE TAFS ARE ISSUED. ACTIVITY WILL CONTINUE
INTO THIS EVENING UNTIL THE LOW AND MAIN COLD FRONT SHIFT EAST
LATE TONIGHT INTO FRIDAY. AT LEAST A PERIOD OF IFR CONDITIONS
STILL LOOKS LIKELY NEAR/AFTER 12Z AS THE UPPER LEVEL SYSTEM MOVES
OVERHEAD AND WILL BE SLOW TO LEAVE...ESPECIALLY AT KFWA.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...FISHER
SYNOPSIS...AGD
SHORT TERM...AGD
LONG TERM...LASHLEY
AVIATION...FISHER
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AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
111 PM CDT THU APR 21 2016
.AVIATION...
MAIN FORECAST ISSUES ARE TIMING OF POSSIBLE TSRA LATER THIS
AFTERNOON AND EVENING AND POSSIBILITY OF LOW STRATUS AND PATCHY
FOG WHEN SHRA/TSRA DIMINISH OVERNIGHT INTO EARLY FRIDAY MORNING.
FOR THE TSRA...INCLUDED A 3 HOUR TEMPO GROUP STARTING 21-23Z THIS
AFTERNOON WHEN POTENTIAL APPEARS HIGHEST...AND LOWER IFR/LIFR
CONDITIONS AT A FEW AIRPORTS AFTER 09Z TONIGHT. 22/TD
&&
.PREV DISCUSSION... /ISSUED 346 AM CDT THU APR 21 2016/
SHORT TERM...
FRONTAL ZONE EXTENDING ROUGHLY ALONG THE MISSISSIPPI VALLEY
APPEARS TO BE WEAKENING IN FAVOR OF BETTER UPPER DYNAMICS AND
SUPPORT FARTHER WEST IN NORTH TEXAS. THE LEADING FRONT MAY SERVE
AS A LOCAL FOCUS FOR CONVECTION WITH SOME HEATING BUT COMPLEX OF
STORMS MOVING ALONG THE COAST IN WHAT APPEARS TO BE A MINOR MCV
MAY IMPEDE INFLOW AS WELL AS PROVIDE THICK CANOPY OVER THE AREA
THIS MORNING. LATEST HRRR MODEL RUN DOES SHOW THIS SCENARIO WITH
ONLY MODEST COVERAGE OVER LAND AREAS AND MORE ROBUST CONVECTION
OVER THE NEAR SHORE WATERS. WILL INDICATE 50-60 PERCENT RAIN
CHANCES TODAY BUT MCV PROGRESSION WILL MAINTAIN UNCERTAINTY ON QPF
EXPECTATIONS. WPC HAS OUTLOOKED A SLIGHT RISK FOR FLASH FLOODING
THAT MAY POTENTIALLY MATERIALIZE LATER TODAY. BETTER FRONTAL
FORCING IS THEN EXPECTED OVERNIGHT INTO FRIDAY MORNING BUT ARE IN
CONSENSUS IN SHOWING SOME BRIEF STALLING ALONG THE COAST UNTIL THE
DENSER AIR MASS ARRIVES LATE FRIDAY INTO EARLY SATURDAY. RAIN
CHANCES WILL BE MAINTAINED THROUGH FRIDAY NIGHT WITH CONSIDERABLE
IMPROVEMENT EXPECTED FOR THE WEEKEND. 24/RR
LONG TERM...
SURFACE HIGH PRESSURE TO PROVIDE FAIR WEATHER THROUGH EARLY
MONDAY. A FRONTAL ZONE IN THE NORTHERN STATES WILL USHER A TROWAL
ALONG THE LOWER MISSISSIPPI VALLEY TO AID IN FOCUSING RAINFALL
ONCE AGAIN OVERNIGHT MONDAY. SUPPORT FOR CONVECTION WILL BE
LIMITED AND WANING UPON ARRIVAL AS HIGH PRESSURE BUILDS FROM THE
EAST TO BRING ABOVE NORMAL TEMPERATURES AND LOWER RAIN CHANCES
LATTER PART OF THE FORECAST PERIOD. 24/RR
AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL TODAY OUTSIDE OF SHOWERS AND
STORMS. A SYSTEM WILL BE MOVING INTO THE AREA BRINGING A CHANCE OF
SHOWERS AND THUNDERSTORMS TODAY. THE BEST CHANCE FOR RAIN WILL BE
THIS AFTERNOON ACROSS THE AREA. EXPECT THE RAIN CHANCES TO REMAIN
HIGH INTO THE EVENING AND OVERNIGHT HOURS. WILL HAVE TO MAKE SOME
CHANGES WITH THE NEXT ISSUANCE AND WILL HAVE MONITOR THE
SITUATION THROUGHOUT THE DAY. 13/MH
MARINE...
EXPECT GENERALLY LIGHT EAST TO SOUTHEAST WINDS. A COLD FRONT IS
STILL EXPECTED TO MOVE THROUGH THE COASTAL WATERS ON FRIDAY. EXPECT
OFFSHORE WINDS LATE FRIDAY AND SATURDAY BEFORE QUICKLY VEERING BACK
TO ONSHORE SUNDAY AS HIGH PRESSURE MOVES OVER THE EASTERN GULF AND
ALONG THE ATLANTIC COAST. 13/MH
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...MINOR RIVER FLOODING.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 77 61 79 58 / 60 60 40 10
BTR 80 63 81 59 / 70 60 40 10
ASD 78 65 80 61 / 50 50 40 10
MSY 79 66 79 64 / 50 40 40 20
GPT 77 66 78 63 / 50 40 40 20
PQL 77 64 78 61 / 40 30 40 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
102 PM CDT THU APR 21 2016
.DISCUSSION...
21/18Z TAF ISSUANCE.
&&
.AVIATION...
YET ANOTHER COMPLEX OF SHRA/TSRA CROSSING THE AREA
TODAY...CURRENTLY EXTENDING FM THE LAKES REGION SOUTH TOWARD
BEAUMONT. TIMED TEMPO GROUPS AT EACH SITE BASED ON CURRENT TRENDS
AND HI-RES GUIDANCE...WITH THE LINE NOW APPROACHING BPT...REACHING
AEX/LCH 20-24Z...AND LFT/ARA 22-01Z. WIND GUSTS TO NEAR 40 KT...VERY
HEAVY RAINFALL AND FREQUENT LIGHTNING WILL ACCOMPANY THE STRONGEST
STORMS. OTHERWISE...VFR CONDITIONS PREVAIL OUTSIDE OF
CONVECTION WITH SLY WINDS 5-10 KT. EXPECT CIGS TO LOWER THIS
EVENING TO MVFR WITH WINDS BCMG LT. PATCHY FOG WILL BE POSSIBLE
OVERNIGHT...REDUCING VSBYS TO MVFR BETWEEN 08-13Z. EXPECT
IMPROVING CONDITIONS FRIDAY MORNING...WITH DRIER AIR BEGINNING TO
MOVE INTO THE AREA.
24
&&
.PREV DISCUSSION... /ISSUED 956 AM CDT THU APR 21 2016/
UPDATE...
SATELLITE BEGINNING TO SHOW ENHANCED AREAS OF NEW CONVECTION
DEVELOPING ACROSS SOUTHEAST TEXAS AND THUS WE START ANEW AGAIN
WITH THE RAIN...IT`S COMING. WE HAVE A CONSISTENT MESSAGE...POPS
REMAIN HIGH ACROSS THE AREA...A FLASH FLOOD WATCH IS IN EFFECT
TODAY..WE HAVE A SATURATED GROUND ...AND FLOODING RAINS ARE
LIKELY TO OCCUR. DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE
ROADS...TURN AROUND DON`T DROWN. DO NOT GO NEAR CREEKS...DITCHES
OR DRIVE INTO LOW AREAS LIKE UNDERPASSES...THESE ARE REALLY
DANGEROUS PLACES TO BE IN FLASH FLOODING RAINS.
DEWPOINTS HAVE RECOVERED ACROSS SOUTHEAST TEXAS AND HRRR INDICATES
THIS WILL BE A FAVORABLE PLACE FOR FLOODING RAINS TO DEVELOP AND
MOVE EAST ACROSS THE I-10 CORRIDOR AREA. WPC INDICATING 2 TO 3
INCH RAINS COULD DEVELOP FAIRLY QUICKLY ONCE THE STORMS
BEGIN...THEREFORE ...FLASH FLOOD WARNINGS ARE LIKELY IN THE NEXT
FEW HOURS. STAY ABREAST OF THE WEATHER FOLKS.
NO CHANGES TO FORECAST...WILL LET IT RIDE.
06
PREV DISCUSSION... /ISSUED 648 AM CDT THU APR 21 2016/
AVIATION...SHOWER AND THUNDERSTORM ACTIVITY OVER THE SOUTHERN
PORTION OF THE AREA EARLIER HAS NOW SETTLED SOUTH INTO THE NEAR
COASTAL WATERS AND WEAKENED. REDEVELOPMENT IS EXPECTED LATE
MORNING AND THROUGH THE AFTERNOON OVER THE AREA AS ANOTHER WEATHER
DISTURBANCE APPROACHES FROM EAST TEXAS AND MOVES ACROSS THE
REGION. EARLY MORNING VISIBILITY RESTRICTIONS ALONG WITH IFR
STRATUS CEILINGS AT BPT AND AEX WILL BE LIFTING SHORTLY. MVFR INTO
VFR CEILINGS WILL GENERALLY PREVAIL AT ALL TERMINALS THROUGH THE
REMAINDER OF THE DAY.
23
PREV DISCUSSION... /ISSUED 423 AM CDT THU APR 21 2016/
DISCUSSION...
BUSY WEATHER PATTERN OVER THE REGION AS THE DISTURBANCE YESTERDAY
IS ANCHORED ALONG THE SOUTHERN LOUISIANA COAST THIS MORNING. THIS
SYSTEM IS EXPECTED TO MOVE EASTWARD THROUGH THE DAY. MEANWHILE
ANOTHER UPPER LEVEL DISTURBANCE IS MOVING INTO CENTRAL TEXAS THIS
MORNING AND LOOKS TO MAKE SOUTHEAST TEXAS DURING THE LATE MORNING/
EARLY AFTERNOON HOURS THEN MOVING INTO SOUTHERN LOUISIANA. THE
RECENT RAINS OVER THE LAST SEVERAL DAYS HAS PRODUCED RAINFALL
TOTAL OVER SIX INCHES IN SOME LOCATIONS AND TWO TO THREE INCHES
IS COMMON ACROSS MOST OF THE REGION. AS A RESULT... THE GROUND IS
COMPLETELY SATURATED... RAINS TODAY ARE EXPECTED TO FLOW INTO LOW
LYING AREAS...STREAMS AND BAYOUS. A FLASH FLOOD WATCH WILL
CONTINUE THROUGH THE MORNING INTO THE AFTERNOON HOURS.
ABOUT THE ONLY GOOD NEWS IS BEHIND THIS NEXT DISTURBANCE WILL BE A
SLOW MOVING COOL FRONT THAT WILL FINALLY BRING THE AREA SOME REST
FROM THE RECENT RAINS. FRIDAY AND INTO THE WEEKEND LOOKS TO BE
DRY. THE DOWN SIDE IS MORE RAINS ARE EXPECTED LATE SUNDAY INTO
MONDAY AS ANOTHER UPPER LEVEL DISTURBANCE MOVES INTO THE REGION.
19
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 78 62 80 59 / 70 40 20 10
LCH 78 66 81 63 / 70 40 20 10
LFT 80 66 81 62 / 70 40 30 10
BPT 79 64 82 63 / 70 30 20 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH UNTIL 6 PM CDT THIS EVENING FOR LAZ027>033-
041>045-052>055-073-074.
TX...FLASH FLOOD WATCH UNTIL 6 PM CDT THIS EVENING FOR TXZ180-201-215-
216-259>262.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
623 PM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE WILL BRING PERIODIC SHOWER CHANCES THROUGH FRIDAY
EVENING. HIGH PRESSURE WILL BRING DRY AND SEASONAL WEATHER THIS
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
QUICK UPDATE TO THE FORECAST TO ADD MENTION OF ISOLATED
THUNDERSTORMS AS LATEST RADAR SHOWS A FEW RELATIVELY WEAK STORMS
POP UP OVER EASTERN OHIO /WESTERN PA. LATEST RAPID UPDATE RUNS
PICK THIS UP REASONABLY WELL SO HAVE ALSO WEIGHTED POPS OVER THE
NEXT SEVERAL HOURS TOWARDS THE LATEST HRRR AND RAP. HOURLY
TEMPERATURES ACROSS WESTERN ZONES WERE ALSO ADJUSTED DOWN AS RAIN
FALLING THROUGH THE INITIALLY VERY DRY LOWER LEVELS QUICKLY
LOWERED TEMPERATURES A COUPLE DEGREES.
SHOWERS ARE EXPECTED TO INCREASE IN COVERAGE LATE THIS
EVENING...PRIMARILY WEST OF LINE RUNNING ROUGHLY FROM INDIANA TO
PARKERSBURG AS A SHORTWAVE TROUGH TRANSITIONS NORTHEAST ACROSS THE
UPPER OHIO VALLEY AHEAD OF THE PARENT UPPER LOW. ITS POSSIBLE WE
MAY NEED TO INCLUDE MENTION OF ISOLATED THUNDERSTORMS WITH THE
NEXT UPDATE AS WELL AS THERE IS SOME ELEVATED INSTABILITY ON
LATEST MODEL SOUNDINGS...AND THE CROSSING SHORTWAVE MAY BE JUST
ENOUGH OF A KICKER. AT THE MOMENT...THE PROGGED INSTABILITY IS
JUST TOO WEAK. OVERNIGHT LOW TEMPERATURES WILL RANGE 10-15 DEG
ABOVE NORMAL WITH CONTINUED WARM AIR ADVECTION AND CLOUD COVERAGE
LIMITING ANY RADIATIONAL COOLING.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
SHOWERS SHOULD TAPER OFF IN COVERAGE FRI MRNG AS THE INITIAL
SHORTWAVE EXITS. THE UPR LOW/TROF...AND IT/S ASSOCIATED SFC COLD
FRONT...IS EXPECTED TO ADVANCE E TWD THE AREA BY AFTN WITH
INCREASING SHOWER POTENTIAL RETURNING. MODEL PROGS SHOW A
POTENTIAL FOR WEAK INSTABILITY...SO ONLY INCLUDED A SLGT CHC OF A
TSTM. THE FRONT SHOULD COMPLETE IT/S PASSAGE FRI NIGHT...THOUGH
SHOWER CHCS SHOULD CONTINUE UNTIL THE UPR TROF AXIS MOVES E OF
THE AREA SAT MRNG.
BUILDING RIDGING IS THEN EXPECTED TO BRING DRY WEATHER THROUGH
THE REST OF THE WEEKEND. TEMPERATURES ARE EXPECTED TO AVERAGE
NEAR OR SEVERAL DEGREES ABOVE SEASONAL LVLS USING GFS MOS AND A
CONSENSUS BLEND GUIDANCE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A COLD FRONT WILL SLOWLY CROSS THE REGION LATER MONDAY THROUGH
TUESDAY BRINGING SHOWERS. BUBBLE OF HIGH PRESSURE WITH DRY BUT
STILL MILD CONDITIONS WEDNESDAY. LOW PRESSURE ADVANCING FROM THE
NATIONS MID SECTION WILL RETURN SHOWERS FOR LATE WEEK. A SLIGHTLY
MODIFIED SUPERBLEND WAS USED FOR THE EXTENDED FORECAST.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
GENERAL VFR EARLY TONIGHT AS LOW LEVELS SLOWLY MOISTEN AHEAD OF
APPROACHING LOW PRESSURE. DEEPER MOISTURE AND BETTER LIFT WILL
GIVE MVFR IN SHOWERS BEFORE DAYBREAK FRIDAY WITH IFR CIGS INTO
NORTHERN PORTS.
.OUTLOOK /FRIDAY THROUGH TUESDAY/...
RESTRICTIONS EXPECTED FRIDAY AS LOW PRESSURE MOVES EAST. NEXT
CHANCE FOR WIDESPREAD RESTRICTIONS WILL BE MONDAY NIGHT AND
TUESDAY AS A COLD FRONT APPROACHES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
407 PM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE WESTERN ATLANTIC TONIGHT. A COLD
FRONT WILL APPROACH FROM THE WEST FRIDAY...PUSHING OFF THE COAST
EARLY SATURDAY MORNING. AN UPPER LEVEL DISTURBANCE DROPS OVER THE
REGION SATURDAY. HIGH PRESSURE RETURNS FOR SATURDAY NIGHT INTO
MONDAY. THE NEXT COLD FRONT PUSHES ACROSS THE REGION TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST REGIONAL RADAR MOSAIC DEPICTS ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS EXTENDING FROM SE NC INTO CENTRAL NC THIS
AFTERNOON. BASED ON LATEST SFC OBS...THE WARM FRONT HAS LIFTED INTO
THE LOCAL AREA...WITH BETTER DESTABILIZATION SOUTH OF THE LOCAL
AREA. EXPECT THE BETTER INSTABILITY TO REMAIN SOUTH OF THE
REGION...BUT HI-RES GUIDANCE CONTINUES TO INDICATE THE POTENTIAL FOR
ISOLATED TO WIDELY SCATTERED SHOWERS LIFTING INTO SRN VA AND NE NC
THRU LATE THIS AFTERNOON. NAM12 300K SURFACES BACK UP THIS
SCENARIO...INDICATING LOW LEVEL LIFT EVEN UNDER THE UPPER LEVEL RIDGE
LOCATED OVER THE ERN CONUS. RAP SOUNDINGS INDICATE MODEST CAPE
EXTENDING INTO THE MIXED PHASE LAYER...SO WILL MENTION SLIGHT CHANCE
FOR THUNDER. ANY SHOWERS THAT DO DEVELOP WILL DISSIPATE EARLY
EVENING WITH THE LOSS OF DAYTIME HEATING.
TEMPS HAVE WARMED INTO THE MID/UPPER 70S...WITH A FEW LOCALES
HITTING 80 ACROSS THE PIEDMONT INTO CENTRAL VA. SOUTH WINDS AROUND
10 MPH TONIGHT ALONG WITH A PARTLY CLOUDY SKY WILL RESULT IN MILD
OVERNIGHT TEMPS. LOWS GENERALLY IN THE LOW 60S (~+1 STD DEV OR 10-12
DEGS ABOVE NORMAL).
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
GENERAL MODEL TRENDS CONTINUE TO SLOW THE UPPER SYSTEM SLIGHTLY AND
DIG IT FARTHER SOUTH AND WEST THROUGH FRIDAY NIGHT. CURRENT NATIONAL
RADAR TRENDS OVER THE OH VALLEY...DEPICT RATHER UNORGANIZED
CONVECTION ASSOCIATED WITH THE UPPER LOW. THE UPPER LOW PUSHES INTO
THE TN VALLEY AS A STRONG UPPER LOW DEEPENS OVER ERN CANADA. THE
FRONT REACHES THE ERN VA PIEDMONT LATE FRIDAY INTO EARLY FRI
EVENING. LEAD SHORTWAVE ENERGY ROUNDS THE BASE OF THE UPPER
TROUGH...LIFTING INTO THE REGION FRI AFTERNOON AHEAD OF THE MAIN
TROUGH ENERGY. RETURN FLOW ADVECTS DEEPER MOISTURE INTO THE
REGION...WITH H85 FLOW COMING IN FROM THE GULF STREAM. POPS RAMP UP
OVER THE PIEDMONT MID TO LATE MORNING...AND THEN POINTS EWD THROUGH
EARLY AFTERNOON. THE FAVORED AREAS FOR SHOWERS CONTINUE TO BE ALONG
AND SOUTH OF A LINE FROM FARMVILLE TO RICHMOND AND TO THE NRN
NECK/MD ERN SHORE FRI AFTERNOON AND FRIDAY EVENING. HAVE MAINTAINED
LIKELY POPS FOR THAT AREA. HAVE TRIMMED BACK POPS NORTH AND WEST OF
THIS LINE AS MODELS INDICATE SHOWER COVERAGE ASSOCIATED WITH THE
MAIN SHORTWAVE WILL BE LIMITED IN THAT REGION. THUNDERSTORM
POTENTIAL REMAINS MARGINAL DUE TO CONSIDERABLE CLOUD COVER AND
MARGINAL INSTABILITY. GIVEN THE DYNAMICS...THETA-E ADVECTION AND THE
TIME OF YEAR...WILL KEEP CHANCE MENTION OF THUNDER. SHEAR REMAINS
MODEST (AOB 30 KT)...SO EXPECT ONLY EMBEDDED THUNDER. PWATS CLIMB TO
1.25 TO 1.5 INCHES...WHICH MAY RESULT IN PERIODS OF MODERATE TO
LOCALLY HEAVY RAINFALL. HOWEVER...QPF AMOUNTS THRU FRIDAY EVENING
WILL GENERALLY RANGE FROM LESS THAN ONE QUARTER OF AN INCH ACROSS
THE NORTH UP TO ONE HALF INCH ACROSS THE SOUTH. AREA REMAINS IN WARM
SECTOR WITH RETURN FLOW PUSHING TEMPS BACK INTO THE MID/UPPER
70S...EVEN WITH CONSIDERABLE CLOUD COVER. SHORTWAVE DROPS OVER THE
CENTRAL APPALACHIANS INTO THE LOCAL AREA THRU FRI NIGHT AS THE FRONT
PUSHES OFFSHORE. WILL KEEP SOLID CHANCE POPS ALONG THE COAST THRU
THE OVERNIGHT PERIOD.
AFOREMENTIONED MODEL TRENDS MEAN LINGERING MID LEVEL MOISTURE TO
GO ALONG WITH THE STRONG DYNAMICS PROVIDED BY THE UPPER LOW DROPPING
OVER THE REGION SAT. WILL HOLD ONTO SOLID CHANCE POPS THROUGH LATE
MORNING INLAND FOR SCATTERED SHOWERS...AND ALONG THE COAST THRU SAT
AFTERNOON. CLOUDY CONDITIONS BECOME PARTLY CLOUDY INLAND SAT
AFTERNOON...BUT REMAIN MOSTLY CLOUDY ALONG THE COAST. TRENDED TOWARD
THE COOLER SIDE OF THE MOS GUIDANCE DUE TO CLOUD COVER AND MODEST
CAA...BUT TEMPS REMAIN SEASONABLE IN THE UPPER 60S/LOW 70S.
NORTH WINDS GENERALLY 10 TO 15 MPH WITH GUSTS OF 20 TO 25 MPH. TROUGH
AXIS PUSHES OFFSHORE SAT NIGHT WITH DRY CONDITIONS FORECAST ACROSS
THE AREA. LOWS IN THE MID/UPPER 40S INLAND TO LOW 50S NEAR THE COAST
UNDER A CLEAR SKY. HIGH PRESSURE BUILDS ACROSS NEW ENGLAND SAT
NIGHT...PARKING OFF THE NORTHEAST COAST SUNDAY. THE RESULT WILL BE
ONGOING DRY CONDITIONS. CAA WANES SUN...BUT LIGHT ONSHORE FLOW WILL
KEEP TEMPS IN CHECK. THICKNESSES YIELD TEMPS IN THE LOW/MID 70S
INLAND AND MID/UPPER 60S ALONG THE COAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SLIDES FARTHER OFFSHORE SUNDAY NIGHT AND MONDAY...AND
SETTLES OFF THE SOUTHEAST COAST BY TUESDAY. MEANWHILE...A SHORTWAVE
TROUGH AND AN ASSOCIATED COLD FRONT APPROACH FROM THE NW BY TUESDAY
AFTN. MONDAY AND TUESDAY ARE TRENDING TOWARD BEING VERY WARM DAYS
WITH DEEP LAYER WSW FLOW ASSOCIATED WITH A BREAKING DOWN UPPER RIDGE
OVER THE E-CENTRAL/SERN CONUS. MODEL CONSENSUS GENERALLY SUPPORTS
850MB TEMPERATURES OF 12-15C...WHICH WITH FULL MIXING AND
DOWNSLOPING SHOULD EASILY PUSH HIGHS TO 80-85F W OF THE BAY...WITH
UPPER 70S FOR THE ERN SHORE. LOWS SUNDAY NIGHT SHOULD BE IN THE
LOW/MID 50S...WITH 55-60F MONDAY NIGHT. SKY COVER SHOULD GENERALLY
BE MOSTLY CLEAR/SUNNY SUNDAY NIGHT...MONDAY INTO MONDAY NIGHT...AND
BECOME PARTLY SUNNY TUESDAY. THE TROUGH AND COLD FRONT SWING THROUGH
THE AREA TUESDAY AFTN INTO TUESDAY NIGHT. THE MAIN FORCING
ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH GENERALLY PASSES N OF
THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES AS THE FEATURE PASSES
OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY 20%...WITH A NARROW
STRIP OF 30% ACROSS THE FAR N. HIGH PRESSURE BUILDS IN FROM THE N
WEDNESDAY...AND SLIDES OFFSHORE LATER IN THE WEEK. HIGHS WEDNESDAY
SHOULD DROP BACK TO THE MID/UPPER 60S NE...TO THE MID/UPPER 70S
FARTHER INLAND...AND THEN TREND UPWARD INTO THURSDAY AS THE HIGH
SLIDES OFFSHORE. LOWS SHOULD GENERALLY BE IN THE 50S.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
VFR CONDS CONTG THROUGH BALANCE OF FCST PD. SCT-BKN CU 4-6KFT
THROUGH ABT 22-23Z/21...THEN BKN-OVC AC-CI INTO OVRNGT HRS. BKN SC
(2-3KFT) PSBL LT TNGT INTO FRI AS MOISTURE INCREASES AHEAD OF
APPROACHING CDFNT FM THE W. AN ISOLD SHRA...ESP AT THE CST...PSBL
AFT 03-06Z/22...OTRW WILL HAVE MVFR CONDS AND PSBL SCT SHRAS AS
CDFNT APPROACHES RIC ON FRI. MNLY MVFR CONDS AND SCT-LIKELY SHRAS
(SLGT CHC TSTM) FRI AFTN/NGT.
GRADUAL CLEARING OUT/BECOMING VFR SAT AFTN...W/ DRY AND VFR CONDS
CONTG THROUGH MON.
&&
.MARINE...
HIGH PRESSURE IS SITUATED WELL OFFSHORE THIS AFTN...WITH
LOW PRESSURE WELL TO THE W OVER THE MID-MISSISSIPPI VALLEY. THE HIGH
WILL CONTINUE TO SLIDE FARTHER OFFSHORE TONIGHT AS LOW PRESSURE
LIFTS NE OVER THE GREAT LAKES. A SW WIND SHOULD AVERAGE 10-15KT
THROUGH THIS EVENING...AND THEN INCREASE TO 15KT BAY/15-20KT OCEAN
LATER THIS EVENING THROUGH FRIDAY MORNING...BEFORE DIMINISHING
FRIDAY AFTN/EVENING AS THE PRESSURE GRADIENT SLACKENS AS A WEAK COLD
FRONT GRADUALLY DROPS INTO THE REGION. THE COLD FRONT PUSHES THROUGH
THE AREA EARLY SATURDAY MORNING...WITH A SUBSEQUENT NORTHERLY SURGE
MIDDAY SATURDAY...WITH A SECONDARY SURGE SATURDAY EVENING. MARGINAL
SCA CONDITIONS ARE POSSIBLE OVER THE BAY (15-20KT N WIND). HIGH
PRESSURE BUILDS OVER THE AREA SATURDAY NIGHT AND SUNDAY...SLIDES
OFFSHORE MONDAY...AND SETTLES OFF THE SOUTHEAST COAST TUESDAY. SEAS
GENERALLY AVERAGE 2-4FT...WITH 2-3FT WAVES IN THE BAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...AJZ
AVIATION...ALB/MPR
MARINE...AJZ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
218 PM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE WESTERN ATLANTIC TODAY. A COLD FRONT
WILL APPROACH FROM THE WEST FRIDAY...PUSHING OFF THE COAST LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING. HIGH PRESSURE RETURNS FOR
SATURDAY AFTERNOON INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS AN UPPER LEVEL CLOSED LOW
OVER IA THIS MORNING...WITH AN UPPER LEVEL RIDGE OVER THE ERN CONUS.
AT THE SFC...HIGH PRESSURE HAS CENTERED OFFSHORE AS A BROAD AREA OF
LOW PRESSURE ASSOCIATED WITH THE UPPER LOW HAS LOCATED OVER THE
UPPER MIDWEST. THE ATTENDANT COLD FRONT EXTENDS SWWD INTO THE SRN
PLAINS. BETWEEN THESE SFC FEATURES...SLY/RETURN FLOW OVER THE LOCAL
AREA HAS RESULTED IN INCREASING MOISTURE/DEWPOINTS. AN INFLUX IN MID
LEVEL MOISTURE AHEAD OF THE APPROACHING STORM SYSTEM WILL RESULT IN
A PARTLY CLOUDY TO MOSTLY CLOUDY SKY TODAY. THE RAP INDICATES A WEAK
VORT MAX PUSHING ACROSS THE NRN NECK LATE THIS MORNING...WHICH IS
JUST ENOUGH FORCING TO PRODUCE ISOLATED LIGHT SHOWERS. ELSEWHERE...A
LACK OF APPRECIABLE FORCING AND STABLE CONDITIONS UNDER THE UPPER
LEVEL RIDGE WILL RESULT IN DRY CONDITIONS THRU MID AFTERNOON.
SHOWERS OVER THE NRN NECK EXPECTED TO DISSIPATE LATE MORNING/EARLY
AFTERNOON. A WARM FRONT LIFTS ACROSS THE REGION TODAY...WITH MODEST
DESTABILIZATION EXPECTED ACROSS SRN VA AND SE VA/NE NC. MOISTURE
RETURN AND LIFT INDICATED IN THE 300K SURFACES WILL RESULT IN
SHOWERS ACROSS THE AFOREMENTIONED REGION THIS AFTERNOON. AGAIN...A
LACK OF STRONG FORCING FOR ASCENT AND DEEP MOISTURE WILL RESULT IN
ONLY ISOLATED TO WIDELY SCATTERED LIGHT SHOWERS. RETURN FLOW OF 10
TO 15 MPH WILL PUSH TEMPS INTO THE LOW/MID 70S...EVEN WITH CLOUD
COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
EXPECT DRY CONDITIONS TO PREVAIL TNGT...AS A COLD FRONT WILL BE
PUSHING INTO/THRU THE OH AND TN VALLEYS. BUT...WILL KEEP SLIGHT
CHC/CHC POPS FOR EXTRM NW COUNTIES...IN CASE A FEW SHOWERS WELL IN
ADVANCE OF THE FRONT MAKE IT INTO THESE AREAS TWD FRI MORNG. IN
ADDITION...SMOKE FM FIRES IN ERN NC WILL SPREAD SMOKE NWD INTO NE
NC. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR THOSE AREAS
INTO EARLY FRI MORNG. MILD TNGT WITH LOWS IN THE UPR 50S TO LWR
60S.
AFOREMENTIONED UPR LO CONTINUES TO DE-AMPLIFY AS IT TRACKS THRU
THE OH VALLEY DURING FRI...PUSHING THE COLD FRONT INTO WRN VA/NC
BY 00Z SAT. PWATS PROGGED IN THE 1.25 TO 1.4 INCH RANGE AHEAD OF
THE FRONT (+1 STD DEV) FRI AFTN. FORECAST CONTINUES TO FAVOR THE
PROGRESSIVE RUNS OF THE GFS/ECMWF...WITH SHOWERS SPREADING INTO
THE PIEDMONT AND CNTRL VA FRI MORNG...AND THE REST OF THE AREA
FRI AFTN INTO FRI EVENG. INSTABILITY REMAINS MARGINAL ALONG WITH
MEAGER LAPSE RATES AND MODEST SHEAR. ALSO...LITTLE IF ANY
INSTABILITY EXISTS IN THE MIXED PHASE LAYER. HOWEVER...GIVEN THE
TIME OF DAY AND CLIMO...CANNOT RULE OUT EMBEDDED THUNDER AND WILL
LEAVE CHC IN THE FCST. MAIN CONCERN FRI WILL BE THE LACK OF
ADEQUATE FORCING FOR ASCENT...AS THE BEST HEIGHT FALLS REMAIN N
OF THE REGION. IF WE GET ENOUGH LIFT AND MOISTURE FEED...QPF AMTS
COULD RANGE FM .20 TO .40 INCH WITH THESE FRONT. WARM SECTOR AND
RETURN FLO WILL PUSH TEMPS INTO THE MID TO UPR 70S...EVEN WITH
MOSTLY CLOUDY CONDITIONS AND INCOMING PCPN. SHOWERS...AND POSSIBLY
A TSTM...WILL NOW LINGER OVR CNTRL/ERN COUNTIES INTO FRI NGT...AS
00Z/21 GFS/ECMWF MODEL RUNS ARE A LITTLE SLOWER. BULK OF PCPN WILL
MOVE OFF THE CST BY 12Z SAT.
MAINTAINED A SLGT CHC OVR THE REGION THRU SAT MORNG UNTIL THE UPR
TROF SHIFTS OFF THE CST BY 18Z. THEN...DRY CONDITIONS EXPECTED
SAT AFTN INTO SAT NGT...AS HI PRES BLDS IN FM THE NNW. ONLY
EXPECT MODEST CAA BEHIND THE FRONT...AS H85 TEMPS DROP ONLY A FEW
DEGS COMPARED TO FRI...RANGING FROM 6 TO 8C. EXPECT N WINDS OF 10
TO 15 MPH SAT. HIGHS GENERALLY IN THE LWR TO MID 70S (COOLER ALNG
THE CST).
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDS INTO THE MID-ATLANTIC SATURDAY NIGHT AND
GRADUALLY SLIDES OFFSHORE SUNDAY. MOSTLY CLEAR/SUNNY AND DRY
CONDITIONS ARE EXPECTED. LOWS SATURDAY NIGHT WILL BE SEASONALLY COOL
DROPPING INTO THE MID/UPPER 40S FOR MOST OF THE AREA...WITH LOW 50S
FOR SE COASTAL LOCATIONS. HIGHS SUNDAY MODERATE INTO THE LOW/MID 70S
FOR MOST OF THE AREA...BUT ONLY IN THE 60S FOR THE ERN SHORE DUE TO
LIGHT ONSHORE FLOW. THE HIGH SLIDES FARTHER OFFSHORE SUNDAY NIGHT
AND MONDAY AS A COLD FRONT APPROACHES FROM THE N MONDAY. 20/12Z
NUMERICAL GUIDANCE GENERALLY KEEPS THE BOUNDARY N OF THE LOCAL AREA
THROUGH THE DAY MONDAY...WHICH WOULD PLACE THE LOCAL AREA IN DEEP
LAYER SW FLOW WITH A MID/UPPER RIDGE BREAKING DOWN. THIS WOULD
RESULT IN A RATHER WARM DAY...AND HIGHS HAVE BEEN NUDGE UPWARD INTO
THE UPPER 70S/LOW 80S...WITH LOW/MID 70S FOR THE ERN SHORE UNDER A
PARTLY TO MOSTLY SUNNY SKY. THIS IS AFTER LOWS SUNDAY NIGHT IN THE
LOW/MID 50S. THE FRONT GRADUALLY DROPS THROUGH THE AREA TUESDAY. THE
MAIN FORCING ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH
GENERALLY PASSES N OF THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES
AS THE FEATURE PASSES OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY
20-30% (MAINLY N) AT THIS TIME. HIGHS TUESDAY ARE FORECAST TO BE IN
THE 70S AFTER MORNING LOWS IN THE 50S. HIGH PRESSURE BUILDS IN FROM
THE N TROUGH MIDWEEK...AS A LOW PRESSURE SYSTEM WITH LIMITED
MOISTURE APPROACHES FROM THE W. FORECAST HIGHS WEDNESDAY RANGE FROM
THE 60S ALONG THE COAST...TO THE LOW 70S INLAND.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR CONDS CONTG THROUGH BALANCE OF FCST PD. SCT-BKN CU 4-6KFT
THROUGH ABT 22-23Z/21...THEN BKN-OVC AC-CI INTO OVRNGT HRS. BKN SC
(2-3KFT) PSBL LT TNGT INTO FRI AS MOISTURE INCREASES AHEAD OF
APPROACHING CDFNT FM THE W. AN ISOLD SHRA...ESP AT THE CST...PSBL
AFT 03-06Z/22...OTRW WILL HAVE MVFR CONDS AND PSBL SCT SHRAS AS
CDFNT APPROACHES RIC ON FRI. MNLY MVFR CONDS AND SCT-LIKELY SHRAS
(SLGT CHC TSTM) FRI AFTN/NGT.
GRADUAL CLEARING OUT/BECOMING VFR SAT AFTN...W/ DRY AND VFR CONDS
CONTG THROUGH MON.
&&
.MARINE...
WINDS NOW SOUTH AROUND THE HIGH THAT HAS MOVED OFF THE COAST. SOME
CHANNELING POSSIBLE FROM TIME TO TIME TODAY AND TONIGHT...BUT THINK
WINDS WILL AVERAGE BELOW 20 KTS. WAVE GUIDANCE SUGGESTS SEAS OUT
NEAR BUOY 44009 REACH 5 FT FOR A FEW HOURS TONIGHT...BUT CONFIDENCE
IN THIS HAPPENING IS NOT THAT HIGH SO ELECTED TO HOLD OFF ON ANY
HEADLINE WITH THIS FORECAST PACKAGE.
OTW...NEXT CHANCE FOR ANY SCA HEADLINES WILL COME SAT MORNING AS
WINDS TURN NORTH BEHIND A COLD FRONTAL PASSAGE FRI NIGHT. CAA SURGE
APPEARS MINIMAL AT THIS POINT (15-20 KTS) ACROSS THE CHES BAY. HIGH
PRESSURE BUILDS OVER THE AREA SAT NIGHT AND SUN RESULTING IN BETTER
BOATING CONDITIONS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...SAM
SHORT TERM...SAM/TMG
LONG TERM...AJZ
AVIATION...ALB/MPR
MARINE...AJZ/MPR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
327 PM EDT THU APR 21 2016
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 327 PM EDT THU APR 21 2016
AFTER SHOWERS AND ISOLATED THUNDERSTORMS EXIT THE AREA EARLY
TONIGHT...CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN SUNDAY AND
CONTINUE WELL INTO NEXT WEEK. SUNDAY WILL BE WARM WITH TEMPERATURES
APPROACHING 70 IN SOME SPOTS. AFTERWARDS...HIGHS WILL BE NEAR
OR SLIGHTLY ABOVE NORMAL WITH HIGHS IN THE LOWER TO MID 60S.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 327 PM EDT THU APR 21 2016
EXPERIMENTAL HRRR GUIDANCE IS LOOKING ON TRACK AS CLEARING HAS
SPREAD INTO EXTREME SOUTHWEST LOWER MI AND A THUNDERSTORM ALREADY
HAS DEVELOPED OVER NORTHWEST INDIANA. BASED ON EXPECTED MOVEMENT
TO THE NORTHEAST...WE STILL EXPECT THE BEST CHANCES FOR THUNDERSTORMS
WILL BE SOUTH OF I-96 AND EAST OF KALAMAZOO MAINLY BEFORE MIDNIGHT.
AFTER THIS EXPECT AT LEAST SOME PATCHY FOG NEAR THE I-94 CORRIDOR
THE REST OF THE NIGHT.
AFTER TONIGHT...FORECAST CONCERNS ARE MINIMAL WITH RAIN SHOWERS
APPROACHING FROM THE NORTHWEST ON SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 327 PM EDT THU APR 21 2016
A STATIONARY FRONT IS STILL EXPECTED TO SLIDE SLOWLY SOUTH THROUGH
THE CWA SUNDAY INTO MONDAY NIGHT. THIS FRONT WILL HAVE A SOLID GULF
MOISTURE CONNECTION AND THE OVER RIDING ACROSS THIS FRONT SHOULD
PRODUCE A FAIR AMOUNT OF RAIN. IT APPEARS MOST AREAS SHOULD GET A
AROUND AN INCH OF RAIN. THE STEADIEST RAINS SHOULD OCCUR ACROSS
CENTRAL LOWER WHERE THE BEST LIFT PERSISTS ACROSS THE FRONT...AND
OVER AN INCH OF RAIN CERTAINLY SEEMS POSSIBLE HERE. A BIT LIGHTER
RAINS ARE EXPECTED TOWARD I-94. A FEW CLAPS OF THUNDER WILL BE
POSSIBLE BUT NO SEVERE WEATHER IS EXPECTED AT THIS TIME. THE AREA
SHOULD DRY OUT INTO TUESDAY AS A WAVE OF LOW PRESSURE SLIDES ALONG
THE FRONT AND HEADS EAST.
HOWEVER THE DRY SPELL APPEARS BRIEF AS MORE RAIN CHANCES RETURN FOR
WEDNESDAY AND THURSDAY WITH ANOTHER WAVE OF LOW PRESSURE MOVING
ACROSS THE OHIO VALLEY. SIMILAR PATTERN WITH A GOOD CHANCE OF
RAIN...BUT MINIMAL CHANCES FOR SEVERE STORMS.
WE WILL REMAIN MILD UNTIL THE FRONT COMES THROUGH...WITH A COOLER
PERIOD FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 158 PM EDT THU APR 21 2016
THE REGION WAS UNDER A MIX OF IFR AND MVFR EARLY THIS AFTERNOON.
EXPECTING A TREND TO MORE MVFR TOWARD 20Z AS SLIGHTLY DRIER AIR
MOVES IN. HOWEVER WITH THIS DRIER AIR...AND PERHAPS POCKETS OF
SUNSHINE...WE WILL BECOME MORE UNSTABLE AND WIDELY SCATTERED
THUNDERSTORMS WILL BECOME POSSIBLE. I HAVE ADDED VCTS ACROSS ALL
THE TAF SITES FROM MID AFTERNOON INTO THIS EVENING.
SOME PARTIAL CLEARING IS EXPECTED AS A COLD FRONT COMES THROUGH
AROUND 06Z. HOWEVER WITH THIS CLEARING WILL COME FOG DEVELOPMENT.
EXPECT ANOTHER PERIOD OF IFR AFTER 06Z AND PROBABLY LASTING UNTIL
AFTER DAYBREAK. THE HIGHEST CHANCE OF IMPACT FROM THIS FOG WILL BE
ACROSS I-94...AND SOMEWHAT MORE QUESTIONABLE TOWARD I-96.
&&
.MARINE...
ISSUED AT 327 PM EDT THU APR 21 2016
FOG HAS BECOME CONSIDERABLY THICKER IN THE LAST COUPLE HOURS SO IN
COORDINATION WITH IWX HAVE HOISTED A MARINE DENSE FOG ADVISORY.
FOG WILL GET SWEPT OUT OVERNIGHT WHEN STRONG NORTH WINDS SPREAD
SOUTH ACROSS LAKE MICHIGAN. RAPIDLY GROWING WAVES WITH THE
STRONGER WINDS AND A VERY FAVORABLE LONG FETCH WILL GIVE US SMALL
CRAFT ADVISORY CONDITIONS QUICKLY FRIDAY MORNING SO HAVE ALSO
ISSUED A SMALL CRAFT ADVISORY WITH THIS PACKAGE.
&&
.HYDROLOGY...
ISSUED AT 158 PM EDT THU APR 21 2016
RAINFALL LAST NIGHT AND TODAY HAS BEEN LIGHT IN NATURE... WITH FEW
TOTALS EXCEEDING A QUARTER INCH. LEVELS ON MAIN STEM RIVERS CONTINUE
A GRADUAL DECLINE... BUT WE HAVE BEEN SEEING RISES ON SMALLER RIVERS
AND CREEKS. NO FLOODING IN ANTICIPATED TODAY OR TOMORROW.
AFTER A QUIET FRIDAY AND SATURDAY... SUNDAY THROUGH THE REST OF NEXT
WEEK LOOKS FAIRLY ACTIVE. A WIDESPREAD INCH OF RAINFALL IS CERTAINLY
POSSIBLE. RIVERS REMAIN ELEVATED... SO WE COULD SEE SOME RISE ABOVE
BANKFULL AND PRODUCE MINOR FLOODING IN LOWLAND AREAS NEXT WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...DENSE FOG ADVISORY UNTIL 2 AM EDT FRIDAY FOR LMZ844>849.
SMALL CRAFT ADVISORY FROM 8 AM FRIDAY TO 2 AM EDT SATURDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...JK
AVIATION...JK
HYDROLOGY...EBW
MARINE...TJT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
334 PM CDT THU APR 21 2016
.SYNOPSIS...
ISSUED AT 333 PM CDT THU APR 21 2016
H5 ANALYSIS FROM EARLIER THIS MORNING HAD A CLOSED LOW
OVER WESTERN IOWA WITH A TROUGH OF LOW PRESSURE EXTENDING SOUTH INTO
THE ARKLATEX. HT FALLS OF 50 TO 70 METERS WERE NOTED FROM THE MID
MISSISSIPPI VALLEY NORTHWARD TO THE ARROWHEAD OF MINNESOTA. WEST OF
THE TROUGH AND CLOSED LOW...WAS A RIDGE OF HIGH PRESSURE WHICH
EXTENDED FROM THE FOUR CORNERS...NORTH TO NORTHERN MONTANA. WEST OF
THE RIDGE...A TROUGH OF LOW PRESSURE WAS PRESENT FROM THE
ALEUTIANS...SOUTH INTO THE EASTERN PACIFIC...AND WAS ROUGHLY 500
MILES WEST OF THE OREGON AND WASHINGTON COASTS. AT THE SURFACE...LOW
PRESSURE WAS LOCATED OVER CENTRAL IOWA WITH HIGH PRESSURE ANCHORED
ACROSS THE FRONT RANGE OF COLORADO AND WYOMING. ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...WINDS WERE NORTHERLY BETWEEN THESE TWO
SURFACE FEATURES...AND WERE BREEZY THIS AFTERNOON WITH SPEEDS OF 15
TO 25 MPH. UNDER PARTLY CLOUDY SKIES...TEMPERATURES WERE IN THE
UPPER 60S TO AROUND 70.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 333 PM CDT THU APR 21 2016
MAIN FORECAST CONCERNS ARE WIND AND TEMPERATURES. THE UPPER LOW
CONTINUES ITS SLOW EASTWARD TREK AND GETS ABSORBED WITH THE OVERALL
FLOW OVER THE GREAT LAKES. H5 RIDGE BUILDS OVER THE GREAT PLAINS
WHILE A SURFACE TROUGH APPROACHES THE PANHANDLE LATE FRIDAY.
THIS EVENING AND TONIGHT... EFFICIENT MIXING TO NEAR 750HPA AS
INDICATED BY RAP AND HRRR SOUNDINGS AND NEARLY UNIDIRECTIONAL FLOW
CREATING GUSTS TO 25MPH FOR MUCH OF THE AREA. SOUNDINGS ALSO
INDICATE LOW LEVEL LIFT... WHICH IS CONFIRMED BY A GROWING CUMULUS
FIELD OVER WESTERN NEBRASKA. LEFT PRECIP MENTION OUT AS ABUNDANT DRY
AIR EXISTS IN THE MID LEVELS AND SURFACE DEW POINT DEPRESSIONS REACH
30F WEST TO 20F EAST. CLOUDS WILL CLEAR TONIGHT WITH THE LOSS OF
DIURNAL HEATING AND WINDS RELAX WITH BOUNDARY LAYER DECOUPLING.
MADE LITTLE CHANGE TO MIN TEMPS AS MID/UPPER 30S SEEMED REASONABLE
GIVEN CLEAR SKIES... LIGHT WINDS... AND NEGLIGIBLE TEMP ADVECTION AT
H85.
FRIDAY... CONTINUED THE TREND OF FOLLOWING WARMER GUIDANCE OR GOING
SLIGHTLY ABOVE FOR MAX TEMPS. RETURN FLOW SWITCHES LOW LEVEL WINDS
TO SOUTHERLY... AND MODELS IN AGREEMENT WITH APPRECIABLE WAA. H85
TEMPS RANGE FROM NEAR 20C PANHANDLE TO 10C NORTH CENTRAL... ABOUT 5
TO 10C WARMER THAN THURSDAY. LOW LEVEL WINDS STRENGTHEN THROUGHOUT
THE DAY AS THE PRESSURE GRADIENT INCREASES AHEAD OF THE TROUGH. NAM
SHOWING AROUND 1MB/HR FALLS DURING THE AFTERNOON. COUPLED WITH
SUBSIDENCE AND MIXING TO NEAR 800HPA WHERE H85 WINDS APPROACH
30KTS... GUSTS MAY REACH 25 TO 30MPH AT THE SURFACE. DESPITE WARM
TEMPERATURES AND BREEZY WINDS... FIRE WEATHER DOES NOT APPEAR TO BE
A SIGNIFICANT ISSUE AT THIS TIME. NAM...GFS...AND EURO KEEP SFC DEW
POINTS IN THE 40S DURING THE AFTERNOON... AND MIXING RATIOS INCREASE
1-2G/KG SINCE THURSDAY. MINIMUM RH VALUES STAY ABOVE 25 PERCENT
PANHANDLE AND 30 PERCENT EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 PM CDT THU APR 21 2016
MID RANGE...FRIDAY NIGHT THROUGH SUNDAY...A TROUGH OF
LOW PRESSURE ALOFT WILL COME ONSHORE ACROSS NRN CALIFORNIA/OREGON
LATE FRIDAY. THIS FEATURE WILL TRACK EAST INTO WYOMING OVER THE NEXT
24 HOURS...MAKING IT AS FAR EAST AS NWRN WYOMING BY 00Z SUNDAY.
DURING THIS PERIOD...A STRONG LEE SIDE SFC CYCLONE WILL DEVELOP OVER
EASTERN WYOMING AND NERN COLORADO. EAST OF THIS FEATURE...SRLY WINDS
WILL INCREASE FRIDAY AFTERNOON INTO FRIDAY NIGHT. SRLY FLOW WILL
PUSH LOW LEVEL MOISTURE NWD DURING THE NIGHT AND THIS COUPLED WITH
THE SRLY WINDS...WILL MAKE FOR MILD TEMPS FRIDAY NIGHT. FCST LOWS
WILL BE IN THE UPPER 40S TO AROUND 50...SOME 10 TO 15 DEGREES ABOVE
NORMAL. ON SATURDAY...STRONG LOW LEVEL WARM AIR ADVECTION WILL
CONTINUE WITH H85 TEMPS REACHING 25C IN THE WEST BY 00Z SUN. THE
LATEST GUIDANCE REFLECTED THESE WARMER TEMPS SHOWN IN THE GRAPHICAL
NAM AND GFS FCST MODELS FROM THIS MORNING...AND HAVE TRENDED UP
HIGHS FOR SAT AFTN. THIS RESULTED IN HIGHS IN THE LOWER 80S ACROSS
THE BOARD. WE EVEN MAY SEE SOME MIDDLE 80S IN THE NORTHWEST WHERE
DRIER AIR IS EXPECTED SAT AFTN. ON SATURDAY EVENING...A PACIFIC COLD
FRONT WILL APPROACH THE PANHANDLE SAT EVENING...AND A LEAD
DISTURBANCE WILL APPROACH SWRN NEBRASKA FROM NERN COLORADO.
THUNDERSTORM CHANCES WILL INCREASE DURING THE EVENING HOURS WITH THE
BEST CHANCES IN THE SOUTHWEST IN PROXIMITY TO THE UPPER LEVEL
WAVE...AND IN THE NORTHWESTERN CWA INVOF THE FRONT AND CLOSER
PROXIMITY TO THE H5 LOW. AS FOR THE THREAT FOR SEVERE STORMS...WAS
CONCERNED SOMEWHAT ABOUT THE 2000 J/KG CAPES DEPICTED IN THE 12Z
NAM SOLN THIS MORNING...ACROSS CENTRAL PORTIONS OF THE CWA.
HOWEVER...BULK SHEAR IS ONLY 15 TO 20 KTS SAT AFTN/EVE...SO THE
SEVERE THREAT APPEARS MINIMAL ATTM. ON SUNDAY...THE UPPER LEVEL LOW
WILL TRACK ALONG THE NEBR/SD BORDER. ATTM...THE MAIN THREAT FOR PCPN
WILL CONTINUE OVER NRN NEBRASKA WITH MAINLY DRY CONDS IN THE SOUTH.
IT WILL BE WINDY WITH DECENT NORTHWESTERLY WINDS BEHIND THE COLD
FRONT SUNDAY. TEMPERATURES WILL RANGE FROM AROUND 60 IN THE WEST TO
THE MID 70S IN THE FAR EAST.
LONG RANGE...SUNDAY NIGHT THROUGH THURSDAY...AN ACTIVE SWRLY FLOW
PATTERN WILL CONTINUE INTO NEXT WEEK. THE FIRST OF TWO UPPER LEVEL
LOWS WILL APPROACH THE FORECAST AREA MONDAY NIGHT WITH LIKELY PCPN
EXPECTED FOR TUESDAY INTO TUESDAY NIGHT. PCPN WILL LINGER IN THE
NORTH FOR WEDNESDAY...WITH DRY CONDS EXPECTED WEDS NIGHT INTO
THURSDAY. A SECOND SYSTEM WILL APPROACH THE REGION LATE THURSDAY
WITH ANOTHER ROUND OF PCPN ON TAP FOR FRIDAY INTO SATURDAY NEXT
WEEK. TEMPERATURES WILL BE COOL WITH HIGHS IN THE 50S WITH SOME 40S
POSSIBLE IN NRN NEBRASKA TUES/WEDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1215 PM CDT THU APR 21 2016
VFR CONDITIONS WILL CONTINUE ACROSS WESTERN NEBRASKA THROUGH
FRIDAY AFTERNOON. GUSTY NORTH WINDS THIS AFTERNOON WILL DIMINISH
AROUND SUNSET AND TRANSITION TO SOUTHERLY BY FRIDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 333 PM CDT THU APR 21 2016
RISES ON THE SOUTH PLATTE RIVER EXPECTED TO CONTINUE
OVER THE NEXT SEVERAL DAYS. UPSTREAM GAUGE AT JULESBURG STILL
SHOWING A SLOW RISE WITH AN EXPECTED CREST AT ROSCOE OF AROUND 7.3
FEET LATE FRIDAY/EARLY SATURDAY. ISSUED RVS THIS MORNING WITH
UPDATED FORECAST FROM MBRFC. SLIGHT UPTICK OBSERVED AT NORTH PLATTE
BUT STILL 1.5 FEET BELOW ACTION STAGE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...SNIVELY
HYDROLOGY...SNIVELY
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
100 PM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY MOVE OFFSHORE THROUGH TONIGHT. A
COLD FRONT WILL APPROACH FROM THE WEST FRIDAY, THEN MOVE THROUGH
THE AREA SATURDAY. HIGH PRESSURE WILL BUILD OVER THE AREA SUNDAY
AND MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1250 PM THURSDAY, BASED ON CURRENT OBSERVATIONS, RAISED
MAXIMUM TEMPERATURES THIS AFTERNOON A COUPLE OF DEGREES AREA-WIDE.
PARTLY CLOUDY SKIES CONTINUE WITH INCREASING DEWPOINTS. HIGH
RESOLUTION MODELS SUCH AS THE HRRR AND NSSL WRF INDICATE SCATTERED
SHOWERS DEVELOPING IN THE NEXT COUPLE OF HOURS INLAND, MAINLY WEST
OF HIGHWAY 17. CURRENT POP FORECAST DEPICTS THIS WELL AND NO
CHANGES MADE AT THIS TIME.
THE WHIPPING CREEK WILDFIRE ALONG THE MAINLAND DARE/MAINLAND HYDE
COUNTY BORDER HAS DROPPED TO ABOUT 9800 ACRES...BUT WILL LIKELY
CONTINUE TO PRODUCE SMOKE ISSUES FOR THE NEXT SEVERAL DAYS. IN
COORDINATION WITH THE STATE OF NORTH CAROLINA...AN AIR QUALITY
ALERT HAS BEEN ISSUED FOR SEVERAL COUNTIES BORDERING THE FIRE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
AS OF 330 AM THURSDAY...PRE-FRONTAL WARM SECTOR CONDITIONS
EXPECTED OVERNIGHT AFTER WEAK WARM FRONT MOVES TO N. MODELS IN
AGREEMENT THAT PCPN THREAT WILL REMAIN OFFSHORE. SOUTHERLY WINDS
AND PARTLY TO MOSTLY CLOUDY SKIES WILL KEEP MIN TEMPS IN LOWER
60S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 AM THURSDAY...
FRIDAY THROUGH SATURDAY: LITTLE CHANGE IN REASONING FOR THE LATE
WEEK SYSTEM. A FRONT WILL APPROACH THE AREA FROM THE WEST AND CROSS
THE REGION SATURDAY MORNING. MOISTURE AHEAD OF THE FRONT WILL RAMP
UP THROUGH THE DAY FRIDAY WITH SHOWERS AND SOME STORMS POSSIBLE BY
THE AFTERNOON. PWATS LOOK TO CLIMB TO NEAR 1.5", WITH MARGINAL
INSTABILITY IN PLACE IN THE AFTERNOON/EVENING HOURS.
INSTABILITY HAS SEEMED TO INCREASE A BIT WITH THE LATEST MODEL
RUNS, POSSIBILITY GIVEN BETTER CONVERGENCE IN THE MID-LEVELS AND
SFC BASED INHIBITION. THE SHEAR PARAMETERS ALSO LOOKS FAIRLY
MARGINAL THROUGH THIS PERIOD. CONFIDENCE IS INCREASING THAT THERE
WILL BE SOME THUNDERSTORM DEVELOPMENT, ALTHOUGH WIDESPREAD
COVERAGE IS UNLIKELY. PRECIPITATION AMOUNTS WITH THIS FROPA LOOK
TO BE AROUND A QUARTER OF AN INCH WITH LOCALLY HIGHER AMOUNTS
ASSOCIATED WITH ANY THUNDERSTORMS.
SO EXPECT CLOUDS/PRECIP TO INCREASE FRIDAY WITH SOUTHERLY FLOW
ACROSS THE AREA. HIGHS IN THE UPPER 70S INLAND TO AROUND 70 ALONG
THE OBX. LOWS TEMPS BY EARLY SATURDAY MORNING WILL BE AROUND 60
DEGREES. THE INITIAL FRONT WILL PULL THROUGH BY 12Z SATURDAY WITH
NORTHWEST DEVELOPING, FOLLOWED BY A SECONDARY FRONT AROUND MID DAY
WITH WINDS BECOMING NORTHERLY. MOST OF THE PRECIPITATION SHOULD BE
OFFSHORE BY SATURDAY MID-MORNING WITH HIGH PRESSURE MOVING INTO
THE AREA FROM THE NORTH. GIVEN SUBSIDENCE FLOW ACROSS THE REGION,
EXPECT TEMPS SATURDAY TO CLIMB INTO THE MID-70S INLAND TO THE MID
60S ALONG THE OBX. SEVERAL 00Z MODELS CONTINUE TO INDICATE AN
ISOLATED SHOWERS POSSIBLE SATURDAY AFTERNOON AS THE SECONDARY
FRONT AND MID LEVEL TROUGH AXIS PUSHES ACROSS THE AREA SO KEPT
SLIGHT CHANCE POPS THROUGH THE AFTERNOON HOURS.
SATURDAY NIGHT THROUGH MONDAY NIGHT: VERY PLEASANT WEATHER FOR
THIS PERIOD AS AN UPPER RIDGE BUILDS ACROSS THE EASTERN CONUS AND
SFC HIGH PRESSURE ANCHORED ACROSS NEW ENGLAND TRANSITIONS TO THE
SOUTHEAST, EVENTUALLY MOVING OFF THE MID-ATLANTIC COAST BY SUNDAY
AFTERNOON. THIS WILL ALLOW RETURN FLOW TO DEVELOP THROUGH THE
PERIOD. TEMPERATURES WILL RISE INTO THE UPPER 70S INLAND TO THE
MID 60S ALONG THE OBX SUNDAY. WITH THE HIGH PRESSURE OFF THE COAST
AND AN APPROACHING LOW FROM THE NORTHWEST, THE PRESSURE GRADIENT
WILL TIGHTEN WITH STRONG/WARM SOUTHWEST FLOW HELPING TEMPS CLIMB
INTO THE LOW 80S INLAND TO AROUND 70 ALONG THE OBX. LOW TEMPS
DURING THIS PERIOD WILL BE INCREASING, LOW 50S SUNDAY MORNING TO
LOW 60S BY TUESDAY MORNING.
TUESDAY THROUGH WEDNESDAY: THE UPPER RIDGE BREAKS DOWN AS A
DAMPENING SHORTWAVE MOVES INTO THE GREAT LAKES REGION AS WE MOVE
TO THE MIDDLE OF NEXT WEEK. A TRAILING COLD FRONT WILL BE NORTH
OF THE AREA THROUGH THE PERIOD, EVENTUALLY SAGGING INTO THE REGION
TUESDAY NIGHT OR WEDNESDAY. THIS WILL MEAN CONTINUED SOUTHERLY
FLOW TUESDAY AND INCREASED MOISTURE FEED ACROSS THE AREA. AREA OF
CONVERGENCE DOESN`T SEEM TOO STRONG, SUGGESTING NOT TOO MUCH IN
THE WAY OF PRECIPITATION WITH THIS BACKDOOR FROPA. MODELS NOT IN
BEST AGREEMENT WITH THE STRENGTH OF THE SHORTWAVE TO OR THE
TIMING OF THE FRONT AND WILL LIMIT POPS TO SLIGHT CHANCE THIS
PERIOD. TEMPS WILL CLIMB INTO THE MID 80S INLAND TO AROUND 70
ALONG THE OBX.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SHORT TERM /THROUGH 18Z FRIDAY/...INCREASING DEWPOINTS AND A
DEVELOPING LOW-LEVEL INVERSION WILL LEAD TO A PERIOD OF MVFR
CEILINGS LATE TONIGHT/EARLY FRIDAY, MAINLY FROM 08Z-12Z. THINK
MUCH OF THE REMAINDER OF THE TAF CYCLE WILL FEATURE VFR
CONDITIONS, BUT WITH SOME SCATTERED SHOWERS, ESPECIALLY KISO/KPGV
THIS AFTERNOON AND AT ALL SITES FROM LATE MORNING INTO AFTERNOON
ON FRIDAY. SOUTH TO SOUTHWEST WINDS WILL CONTINUE TO GUSTS TO AS
HIGH AS 15-20 MPH LATE THIS AFTERNOON AND EVENING.
LONG TERM /FRIDAY THROUGH MONDAY/
AS OF 330 AM THURSDAY...A FRONT WILL APPROACH FRIDAY AND CROSS
THE REGION SATURDAY MORNING. SHOWERS AND ISOLATED THUNDERSTORM
CHANCES INCREASE FRIDAY AFTERNOON WITH PERIODS OF SUB-VFR
CONDITIONS POSSIBLE CONTINUING THROUGH THE EVENING HOURS
ESPECIALLY WITH ANY HEAVIER SHOWERS/STORMS DURING THIS TIME. GUSTY
SOUTHERLY FLOW AHEAD OF THE FRONT CAN BE EXPECTED FRIDAY,
ESPECIALLY DURING THE AFTERNOON THROUGH THE OVERNIGHT.
PRECIPITATION WILL DIMINISH ACROSS THE TAF SITES EARLY SATURDAY
MORNING AS THE FRONT PUSHES OFFSHORE BUT CANNOT RULE OUT A FEW
SHOWERS CONTINUING THROUGH THE DAY SATURDAY. EXPECT NORTHWEST FLOW
BEHIND THE FRONT SATURDAY MORNING WITH WINDS BECOMING NORTH BEHIND
A SECONDARY FRONT SATURDAY AFTERNOON. HIGH PRESSURE WILL THEN
BUILD INTO THE REGION THROUGH THE REMAINDER OF THE PERIOD WITH
PRED VFR CONDITIONS EXPECTED.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1 PM THURSDAY, SOUTH WINDS CONTINUE AT 5-15 KNOTS THIS
AFTERNOON WITH SEAS HOVERING AROUND 4 FEET. STILL SEEING SOME
6-FOOTER AROUND DIAMOND BUOY AND HAVE ISSUED A MARINE WEATHER
STATEMENT INTO EARLY AFTERNOON. WILL MONITOR AND MAY ISSUE A
SHORT-LIVED SMALL CRAFT ADVISORY FOR THE MIDDLE WATERS IF THIS
TREND CONTINUES. SEAS WILL SUBSIDE TO 2-4 FT THIS AFTERNOON...THEN
BUILD BACK TO 3-5 FT BY TONIGHT.
LONG TERM /FRIDAY THROUGH MONDAY/
AS OF 330 AM THURSDAY...SOUTHERLY FLOW WILL INCREASE AHEAD OF A
FRONT THAT WILL CROSS THE AREA EARLY SATURDAY. EXPECT 15-20 KTS
WITH HIGHER GUSTS FRIDAY AFTERNOON THROUGH THE OVERNIGHT WITH THE
FROPA THROUGH THE WATERS EARLY SATURDAY MORNING. SEAS WILL BUILD
ALONG THE SOUTHERN/CENTRAL WATERS, TOPPING OUT AROUND 5-6FT FRIDAY
NIGHT. NORTHWEST FLOW AROUND 10-15 KTS WILL DEVELOP BEHIND THE FRONT
SATURDAY MORNING, THEN A NORTHERLY SURGE AROUND 10-20 KTS BEHIND A
SECONDARY FRONT WITH SEAS GRADUALLY DIMINISHING TO 2-4 FT. HIGH PRES
WILL BE CENTERED OVER THE AREA SUNDAY THEN WILL MOVE OFFSHORE
MONDAY. NE FLOW AROUND 15 KT OR LESS SUNDAY MORNING DIMINISHES TO 10
KT OR LESS WHILE VEERING TO SOUTHEAST THEN SOUTH SUNDAY AFTERNOON
AND EVENING, BECOMING SW BY MONDAY AND INCREASING TO 10-15 KT WITH
SEAS AROUND 2-4 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR NCZ095-
103-104.
MARINE...NONE.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...SK
AVIATION...CTC/SK
MARINE...CTC/JBM/SK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 PM CDT THU APR 21 2016
.UPDATE...
ISSUED AT 1233 PM CDT THU APR 21 2016
LOW CLOUD COVER CONTINUES TO ERODE WITH MOSTLY SUNNY SKIES OVER
THE AREA.
UPDATE ISSUED AT 911 AM CDT THU APR 21 2016
FOR MORNING UPDATE MAIN CHANGES WERE TO WIND AND CLOUD COVER.
LATEST MAV GUIDANCE HAS A PRETTY GOOD GRASP ON WINDS WHICH ARE
HIGHER THAN PREVIOUS FORECAST SUGGESTED. THEREFORE...HAVE
INCREASED WIND SPEEDS A BIT...PARTICULARLY OVER CENTRAL NORTH
DAKOTA. NEXT CONCERN IS CLOUD COVER WITH SOME EXPANDING AREAS OF
LOW CLOUDS. HRRR RUNS CONTINUE THE EXPANSION OF THE LOW CLOUD
COVER THROUGH THE MORNING...RAISING IT AND BREAKING IT UP IN THE
AFTERNOON. WILL ADDRESS THIS BY RAISING CLOUD COVER OVER MOST
AREAS.
UPDATE ISSUED AT 638 AM CDT THU APR 21 2016
NO CHANGES TO THE FORECAST OTHER THAN TO BLEND TO OBSERVED TRENDS
THROUGH 11 UTC AS THE SURFACE COLD FRONT HAS PROPAGATED THROUGH
NORTH DAKOTA EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT THU APR 21 2016
EARLY THIS MORNING A COLD FRONT CONTINUED TO PUSH SOUTHEAST ACROSS
THE STATE. MOST LOCATIONS HAVE SWITCHED OVER TO NORTHWEST WINDS
AND COLD AIR ADVECTION HAS TAKEN HOLD. TEMPERATURES TODAY WILL BE
COOLER WITH READINGS MAINLY IN THE 50S AS COLD AIR ADVECTION WILL
CONTINUE THROUGH THE DAY.
TONIGHT...HIGH PRESSURE SHIFTS OFF TO THE EAST AND RETURN FLOW
KICKS IN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU APR 21 2016
THE END OF THE WEEK LOOKS RATHER WARM. STRONG WARM AIR ADVECTION
AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM WILL COMBINE WITH
COMPRESSIONAL WARMING TO PRODUCE TEMPERATURES NEAR 80 ACROSS
PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA.
A POTENT SYSTEM IS TAKING AIM ON THE NORTHERN PLAINS FOR SATURDAY
AND SUNDAY. MODELS ARE IN SURPRISINGLY GOOD AGREEMENT WITH TIMING
AND PLACEMENT OF PRECIPITATION. THEREFORE...THUNDERSTORMS AND
WIDESPREAD RAINFALL APPEAR LIKELY AS A STACKED LOW DEVELOPS OVER
SOUTH DAKOTA. AT THIS TIME IT APPEARS PRECIPITATION AMOUNTS NEAR
AN INCH ARE POSSIBLE ACROSS PORTIONS OF SOUTHERN NORTH DAKOTA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1233 PM CDT THU APR 21 2016
VFR CONDITIONS THROUGH THE FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
312 PM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE AND AN ACCOMPANYING FRONTAL SYSTEM WILL MOVE EAST
ACROSS THE MIDWEST AND OHIO VALLEY TOWARD THE REGION TODAY.
SHOWERS SPREADING INTO THE REGION THIS EVENING INTO FRIDAY WILL
BE FOLLOWED BY MILD AND DRY WEATHER THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
MORE EXTENSIVE AND THICKENING MID LEVEL CLOUDS WERE OVERSPREADING
THE CWA LATE TODAY. RADAR ECHOES WERE STILL MAINLY ALOFT...THOUGH
SOME ACROSS THE NW MTNS WITH RETURN AROUND 25 DBZ WERE LIKELY
REACHING THE GROUND AS BRIEF SHOWERS.
LATEST HRRR IS QUITE DRY THROUGH AT LEAST THE FIRST HALF OF
TONIGHT...THOUGH ITS LIKELY A FEW BRIEF SHOWERS WILL STREAK NE
ACROSS THE WESTERN AND NRN MTNS BRINGING SEVERAL HUNDREDTHS TO
PERHAPS ONE-TENTH OF AN INCH OF RAIN AS A WARM FRONT LIFTS NE
ACROSS THE STATE.
THE CLOUDS AND LIGHT SOUTH TO SWRLY LLVL FLOW WILL KEEP TEMPS MILD
OVERNIGHT...MAINLY IN THE MID TO UPPER 50S ACROSS CENTRAL AND SRN
PENN. SOME EVAP COOLING ACROSS THE NWRN ZONES WILL PUSH TEMPS A
LITTLE LOWER...DOWN INTO THE L50S.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
SFC COLD FRONT WILL APPROACH FROM THE OHIO VALLEY FRIDAY. A PLUME
OF HIGH PWAT AIR /25-30MM/ WILL SLIDE EAST ACROSS THE STATE FRIDAY
AND EXIT THE SE ZONES AFTER 06Z SATURDAY.
FRIDAY LOOKS PRETTY CLOUDY AND SHOWERY WITH POPS IN THE 70-80
PERCENT RANGE. SOME SHORT TERM OPER MODEL GUIDANCE SUGGESTS THAT
MU CAPES WILL RAMP UP TO BETWEEN 500-1000 J/KG DURING THE DAY
FRIDAY...THOUGH THE ENSEMBLE MEAN IS SLIGHTLY LOWER AT A FEW TO
SVRL HUNDRED J/KG - JUST ENOUGH TO MENTION ISOLATED TSRA WHERE
SOME BREAKS IN THE CLOUD COVER DEVELOP.
SOME SHOWERS LINGER FRIDAY NIGHT...MAINLY IN THE S/SE AS THE
UPPER LOW AND REAL COLD AIR ALOFT TAKE UNTIL MIDNIGHT OR SO ON
FRIDAY NIGHT TO PASS COMPLETELY THROUGH.
24-36 HOUR QPF IS STILL SLATED TO HOLD TO ONLY 0.25 INCHES SE TO
PERHAPS AROUND 0.5 INCHES NW. EVEN ACROSS THE NW...THE GEFS AND
SREF PROB FOR 0.50 INCH OF RAIN OVER A 24 HOUR PERIOD IS BARELY
OVER 50 PERCENT. LATEST GEFS MINS FRI NIGHT WILL BE REALLY CLOSE
TO NORMAL ACROSS THE NORTH...AND JUST A HAIR ABOVE THEM IN THE
SOUTH.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT IN THE PATTERN
VERSUS PREVIOUS DAYS...SHOWING A MIGRATION FROM A BROAD
TROUGH/RIDGE/TROUGH CONFIGURATION EXTENDING FROM THE GREAT BASIN
TO THE PLAINS INTO THE MID ATLANTIC REGION AT THE START OF THE
PERIOD...TOWARD A MEAN WESTERN TROUGH/BUILDING RIDGE IN THE EAST
BY NEXT THU AS THE STRONG HIGH LATITUDE BLOCKING WEAKENS OVER
GREENLAND/EASTERN CANADA. UNCERTAINTY HAS ALSO DECREASED OVER THE
POSITION OF AN EAST/WEST SFC FRONTAL BOUNDARY AND LOW LEVEL
BAROCLINIC ZONE WITH COLDER TEMPERATURES STAYING WELL TO THE NORTH
OF PA ALONG THE NRN TIER STATES/CANADIAN BORDER.
THE NCEP MODELS ARE WEAKER AND MORE PROGRESSIVE VS. ECMWF/CMC
WITH THE SHORTWAVE TROUGH EXITING THE MID ATLANTIC EARLY SATURDAY.
THIS MAY LINGER CLOUDS/LIGHT RAIN OVER SOUTHERN AREAS DURING THE
MORNING BEFORE HIGH PRESSURE DRYS THINGS OUT BY THE AFTERNOON.
THE WEEKEND AS A WHOLE LOOKS FAIR AND DRY WITH A RISK OF
FROST/FREEZE CONDITIONS SATURDAY NIGHT INTO SUNDAY MORNING. WAVES
OF LOW PRESSURE MOVG EWD ALONG WAVY SFC FRONTAL BOUNDARY PRESSING
SWD FROM THE LOWER LAKES/UPSTATE NY SHOULD BRING PERIODS OF RAIN
EARLY NEXT WEEK BUT CONFIDENCE IN EXACT TIMING OF GREATEST PCPN
RISK IS STILL BELOW AVERAGE AND COULD EASILY SHIFT +/- 12 HOURS.
MODEL CONSENSUS FAVORS A DRY PERIOD ON WEDNESDAY BEFORE RAIN PROBS
TREND HIGHER FROM WEST TO EAST INTO THE SECOND HALF OF NEXT WEEK.
ASIDE FROM A CHILLY SUNDAY MORNING...THE GLOBAL ENSEMBLE MEANS
ALONG WITH NATIONAL/REGIONAL BLENDS ALL SUPPORT ABOVE NORMAL TEMPS
THROUGH THE MEDIUM RANGE PERIOD.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A WARM FRONT LIFTING NORTHEAST INTO THE AREA WILL SPREAD SCT
MAINLY VERY LIGHT SHOWERS INTO THE AREA /MAINLY NEAR AND TO THE
WEST OF A KJST TO KBFD LINE/ LATER TODAY AND TONIGHT.
DRY AIR IN THE LOW LLVLS SHOULD ENSURE VFR CONDS ACROSS THE
ENTIRE AREA THROUGH EARLY THIS EVENING. A BLEND OF LATEST NEAR
TERM MDLS SUGGESTS A BRIEFLY HEAVIER SHOWERS ARE POSSIBLE LATE
TODAY AND TONIGHT ACROSS THE NRN AND WRN MTNS WITH BRIEF VISBY
REDUCTIONS. THE BEST CHC FOR SHOWERS WILL ARRIVE FROM WEST TO EAST
DURING THE MID TO LATE MORNING HOURS FRIDAY...WITH ISOLATED TSRA
IMPACTS POSSIBLE BETWEEN 17-23Z FRIDAY.
OUTLOOK...
FRI...SHOWERS WITH AREAS OF MVFR CIGS AND BRIEF MVFR VSBYS
POSSIBLE /MAINLY ACROSS THE WRN MTNS/. ISOLATED TO SCT PM TSRA
IMPACTS POSSIBLE.
SAT...EARLY AM LOW CIGS POSSIBLE W MTNS.
SUN...NO SIG WX EXPECTED.
MON AND TUESDAY...PM SHRA DEVELOPING MONDAY AND CONTINUING INTO
TUESDAY. REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
217 PM EDT THU APR 21 2016
.SYNOPSIS...
LOW PRESSURE AND AN ACCOMPANYING FRONTAL SYSTEM WILL MOVE EAST
ACROSS THE MIDWEST AND OHIO VALLEY TOWARD THE REGION TODAY.
SHOWERS SPREADING INTO THE REGION THIS EVENING INTO FRIDAY WILL
BE FOLLOWED BY MILD AND DRY WEATHER THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VARYING AMOUNTS OF MID LEVEL CLOUDS WERE SPREADING EAST ACROSS THE
STATE LATE THIS MORNING. ANY RADAR RETURNS ARE WEAK WITH RAIN
EVAPORATING ABOUT 6-8 KFT AGL..IN THE DRY LOW TO MID LEVEL AIR.
TEMPS ARE RUNNING RIGHT ON TRACK WITH HOURLY GRIDDED DATA AND ON
TRACK TO REACH HIGHS IN THE U60S ACROSS THE NRN MTNS...AND LOWER
TO MID 70S ELSEWHERE.
LAST FEW RUNS OF THE HRRR HAVE SHOWN A SLIGHTLY BETTER CHC AND
EARLIER ONSET TIME FOR SCATTERED SHOWERS ACROSS WESTERN AND
CENTRAL PENN LATER THIS AFTERNOON /WEST/ AND EARLY THIS EVENING
/CENTRAL MTNS AND MID SUSQ VALLEY/. STILL...QPF THROUGH THE FIRST
HALF OF TONIGHT SHOULD BE LIGHT AND UNDER ONE TENTH OF AN INCH IN
MOST PLACES...WITH THE EXCEPTION OF THE NW MTNS THAT COULD SEE
AROUND 2 TENTHS OF AN INCH BY 06Z FRIDAY.
WINDS WILL BE SOUTHERLY...AND MAY BE 10-12MPH IN THE SE LATER IN
THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
UPPER LOW OVER THE PLAINS WILL OPEN UP A BIT AND JOIN UP WITH THE
LONG-WAVE TROUGH DROPPING INTO ERN CANADA. THE MOISTURE FEED GETS
BETTER TONIGHT AND FRIDAY...BUT THE UPPER LOW TAKES UNTIL FRI
EVENING/NIGHT TO MOVE OVERHEAD. THE SYSTEM SEEMS TO BE A LITTLE
SLOWER IN PASSING THAN IT APPEARED IN PREVIOUS DAYS. THE SFC LOW
STAYS WELL TO OUR NORTH AS IT OCCLUDES.
SHOWERS WILL BE SPOTTY OVERNIGHT AND HELD MAINLY TO THE NW
HALF/THIRD OF THE AREA. HOWEVER...A STRAY SHOWER MAY ESCAPE INTO
THE EAST. A VERY LOW POP IS WARRANTED FOR THE SE TONIGHT.
FRIDAY LOOKS PRETTY CLOUDY AND SHOWERY. TEMPS WILL STILL BE MILD
DUE TO THE MILD START AND CLOUD COVER. BUT MAXES WILL HOLD A
LITTLE CLOSER TO NORMS FRIDAY THAN THURS - AND MANY PREV DAYS.
THE FORCING WITH THIS SYSTEM IS NEBULOUS AND UPLIFT IS NOT VERY
ORGANIZED. WILL KEEP POPS LOWER THAN CATEGORICAL DUE TO THE
EXPECTED COVERAGE...WHICH SHOULD EVENTUALLY GET EVERY LOCATION
WET. BUT 100POPS SEEMS LIKE OVERKILL FOR THE LARGE BREAKS IN
BETWEEN THE NUMEROUS SHOWERS. FRIDAY NIGHT LOOKS LIKE IT COULD
STILL HOLD SOME SHOWERS...ESP IN THE S/SE AS THE UPPER LOW AND
REAL COLD AIR TAKE UNTIL MIDNIGHT OR SO ON FRIDAY NIGHT TO PASS
COMPLETELY THROUGH. PWATS IN THE 1 TO 1.25 INCH RANGE DO LAST FOR
ABOUT 24 HRS. BUT WITHOUT GOOD EASTERLY/OFF-ATLANTIC FLOW AND ONLY
QUESTIONABLE/DISORGANIZED FORCING...QPF IS STILL SLATED TO HOLD
TO ONLY 0.25 INCHES SE TO 0.6 INCHES NW. MINS FRI NIGHT WILL BE
REALLY CLOSE TO NORMALS NORTH AND JUST A HAIR ABOVE THEM IN THE
SOUTH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT IN THE PATTERN
VERSUS PREVIOUS DAYS...SHOWING A MIGRATION FROM A BROAD
TROUGH/RIDGE/TROUGH CONFIGURATION EXTENDING FROM THE GREAT BASIN
TO THE PLAINS INTO THE MID ATLANTIC REGION AT THE START OF THE
PERIOD...TOWARD A MEAN WESTERN TROUGH/BUILDING RIDGE IN THE EAST
BY NEXT THU AS THE STRONG HIGH LATITUDE BLOCKING WEAKENS OVER
GREENLAND/EASTERN CANADA. UNCERTAINTY HAS ALSO DECREASED OVER THE
POSITION OF AN EAST/WEST SFC FRONTAL BOUNDARY AND LOW LEVEL
BAROCLINIC ZONE WITH COLDER TEMPERATURES STAYING WELL TO THE NORTH
OF PA ALONG THE NRN TIER STATES/CANADIAN BORDER.
THE NCEP MODELS ARE WEAKER AND MORE PROGRESSIVE VS. ECMWF/CMC
WITH THE SHORTWAVE TROUGH EXITING THE MID ATLANTIC EARLY SATURDAY.
THIS MAY LINGER CLOUDS/LIGHT RAIN OVER SOUTHERN AREAS DURING THE
MORNING BEFORE HIGH PRESSURE DRYS THINGS OUT BY THE AFTERNOON.
THE WEEKEND AS A WHOLE LOOKS FAIR AND DRY WITH A RISK OF
FROST/FREEZE CONDITIONS SATURDAY NIGHT INTO SUNDAY MORNING. WAVES
OF LOW PRESSURE MOVG EWD ALONG WAVY SFC FRONTAL BOUNDARY PRESSING
SWD FROM THE LOWER LAKES/UPSTATE NY SHOULD BRING PERIODS OF RAIN
EARLY NEXT WEEK BUT CONFIDENCE IN EXACT TIMING OF GREATEST PCPN
RISK IS STILL BELOW AVERAGE AND COULD EASILY SHIFT +/- 12 HOURS.
MODEL CONSENSUS FAVORS A DRY PERIOD ON WEDNESDAY BEFORE RAIN PROBS
TREND HIGHER FROM WEST TO EAST INTO THE SECOND HALF OF NEXT WEEK.
ASIDE FROM A CHILLY SUNDAY MORNING...THE GLOBAL ENSEMBLE MEANS
ALONG WITH NATIONAL/REGIONAL BLENDS ALL SUPPORT ABOVE NORMAL TEMPS
THROUGH THE MEDIUM RANGE PERIOD.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
A WARM FRONT LIFTING NORTHEAST INTO THE AREA WILL SPREAD SCT
SHOWERS INTO THE AREA /MAINLY NEAR AND TO THE WEST OF A KJST TO
KBFD LINE/ LATER TODAY.
DRY AIR IN THE LOW LVLS SHOULD ENSURE VFR CONDS ACROSS THE ENTIRE
AREA THROUGH MID AFTERNOON. HOWEVER...A BLEND OF LATEST NEAR TERM
MDLS SUGGEST A HEAVIER SHOWER THIS LATE AFTN OR EARLY EVENING
COULD PRODUCE A BRIEF VIS REDUCTION IN SOME SPOTS. BEST CHC WILL
BE ACROSS THE NW MTNS /KBFD/ AND LEAST CHC ARND KMDT/KLNS.
OUTLOOK...
FRI...SCT PM TSRA IMPACTS POSSIBLE.
SAT...EARLY AM LOW CIGS POSSIBLE W MTNS.
SUN...NO SIG WX EXPECTED.
MON...PM SHRA/REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/LAMBERT
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
337 PM CDT THU APR 21 2016
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...LATEST SATELLITE IMAGERY
SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM NORTH OF LAREDO TO NEAR
KINGSVILLE THIS AFTERNOON. THE COMBINATION OF A SOUTHWARD MOVING
BOUNDARY ACROSS SOUTH TEXAS...AN INLAND MOVING SEA BREEZE EXTENDING
FROM BROWNSVILLE TO NEAR CORPUS CHRISTI AND DAYTIME HEATING WILL
SUPPORT THE DEVELOPMENT OF ISOLATED TO SCATTERED CONVECTION FOR THE
REST OF THE AFTERNOON INTO THIS EVENING. BROWNSVILLE RADAR CURRENTLY
SHOWS ISOLATED ACTIVITY ACROSS KENEDY AND WILLACY COUNTIES. THE
STORM PREDICTION CENTER /SPC/ HAS ALL OF DEEP SOUTH TEXAS UNDER A
MARGINAL RISK OF SEVERE WEATHER THROUGH TONIGHT. THE MAIN THREATS
FROM ANY OF THE STORMS THAT DEVELOP THIS AFTERNOON INTO THIS EVENING
WILL BE SMALL HAIL...GUSTY WINDS AND LOCALLY HEAVY RAINFALL.
THE 21Z HRRR INDICATES CONVECTION WILL CONTINUE TO DEVELOP ACROSS
THE COASTAL COUNTIES THROUGH LATE AFTERNOON WITH ADDITIONAL
DEVELOPMENT ACROSS ZAPATA AND STARR THIS EVENING. THE 12Z NAM KEEPS
MOST OF THE CONVECTION OVER THE GULF WATERS...THE 12Z GFS SHOWS A
LITTLE CONVECTION OVER THE VALLEY...AND THE 12Z ECMWF SHOWS MORE
ROBUST CONVECTION ACROSS THE AREA. BASED ON CURRENT TRENDS WILL GO
ABOVE MET/MAV GUIDANCE FOR POPS THROUGH THE REST OF THIS AFTERNOON
AND EVENING.
THE APPROACH AND PASSAGE OF A 500 MB DISTURBANCE ALONG WITH A WEAK
COLD FRONT SAGGING SOUTH WILL GENERATE ISOLATED SCATTERED CONVECTION
OVER PORTIONS OF DEEP SOUTH TEXAS TONIGHT. THE COLD FRONT STALLS
OVER DEEP SOUTH TEXAS FRIDAY AND FRIDAY NIGHT. POOLING MOISTURE IN
ADVANCE OF THIS SURFACE FEATURE WILL COMBINE WITH DAYTIME
HEATING...AND ENHANCED SEA BREEZE EFFECT...AND ANOTHER WEAK 500 MB
DISTURBANCE TO PRODUCE MAINLY SCATTERED CONVECTION ON FRIDAY. LOW
TEMPERATURES TONIGHT WILL GENERALLY BE IN THE LOWER 70S. HIGH
TEMPERATURES FRIDAY WILL RANGE FROM THE LOWER 80S NEAR THE COAST TO
THE UPPER ACROSS THE UPPER VALLEY. LOW TEMPERATURES WILL BE SLIGHTLY
COOLER FRIDAY NIGHT WITH TEMPERATURES FALLING INTO THE MID 60S TO
AROUND 70.
&&
.MARINE...NOW THROUGH FRIDAY NIGHT...BUOY 42020 REPORTED NORTH WINDS
AROUND 2 KNOTS GUSTING TO AROUND 4 KNOTS WITH SEAS SLIGHTLY UNDER
3.3 FEET WITH A PERIOD OF 7 SECONDS AT 15 CDT/19 UTC. A WEAK
GRADIENT ALONG THE LOWER TEXAS COAST WILL MAINTAIN LIGHT TO MODERATE
WINDS AND LOW TO MODERATE SEAS THROUGH THE PERIOD. NO SMALL CRAFT
EXERCISE CAUTION OR SMALL CRAFT ADVISORY ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 73 80 70 79 / 20 30 10 30
BROWNSVILLE 73 83 70 82 / 20 30 20 30
HARLINGEN 72 84 69 83 / 20 30 10 30
MCALLEN 73 87 70 85 / 30 30 10 40
RIO GRANDE CITY 72 88 70 86 / 30 30 20 50
SOUTH PADRE ISLAND 73 77 71 77 / 20 20 20 20
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63/61/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1253 PM CDT THU APR 21 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...THE COMBINATION OF A SOUTHWARD MOVING BOUNDARY
ACROSS CENTRAL TEXAS...THE SEA BREEZE AND DAYTIME HEATING EXPECTED
TO GENERATE ISOLATED TO SCATTERED CONVECTION THIS AFTERNOON.
THE LATEST HRRR MODEL INDICATES SOME ACTIVITY DEVELOPING ACROSS
THE RIO GRANDE VALLEY BETWEEN 19 TO 00Z. WILL MENTION VCTS AT
ALL THREE TAF SITES THIS AFTERNOON. CONVECTION WILL WEAKEN LATER
THIS EVENING WITH THE LOSS OF DAYTIME HEATING. MVFR WITH IFR
CONDITIONS POSSIBLE LATER TONIGHT INTO FRIDAY MORNING DUE TO
POOLING LOW LEVEL MOISTURE AND LIGHT WINDS.
&&
.PREV DISCUSSION... /ISSUED 948 AM CDT THU APR 21 2016/
DISCUSSION...THE COMBINATION OF A SOUTHWARD MOVING BOUNDARY
ACROSS CENTRAL TEXAS...THE SEA BREEZE AND DAYTIME HEATING WILL
SUPPORT THE DEVELOP OF ISOLATED TO SCATTERED CONVECTION FOR THE
REST OF TODAY. THE STORM PREDICTION CENTER /SPC/ HAS PLACE ALL OF
DEEP SOUTH TEXAS UNDER A MARGINAL RISK OF SEVERE WEATHER FOR TODAY
AND TONIGHT. THE MAIN THREATS FROM ANY STORMS THAT DEVELOP THIS
AFTERNOON INTO THIS EVENING WILL BE SMALL HAIL...GUSTY WINDS AND
LOCALLY HEAVY RAINFALL. MADE A QUICK UPDATE TO INCREASE POPS AND
TO MENTION SMALL HAIL...GUSTY WINDS AND HEAVY RAINFALL TO THE
WEATHER GRIDS. THE REST OF THE FORECAST LOOKS GOOD AND NO
ADDITIONAL CHANGES ARE NEEDED AT THIS TIME.
PREV DISCUSSION... /ISSUED 554 AM CDT THU APR 21 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...LIGHT FOG AND MVFR CEILINGS HAVE DEVELOPED DURING THE
OVERNIGHT HOURS. FULL VFR WILL DEVELOP AND PREVAIL AFTER SUNRISE
THIS MORNING WITH MODERATE SURFACE WINDS. MVFR IS ANTICIPATED
AGAIN TONIGHT WITH LOWERED CEILINGS AND MUCH LIGHTER WINDS. ONE
ASPECT OF THE TAF FORECAST THAT MAY NEED TO BE ADJUSTED BY A
FOLLOWING SHIFT IS THE INCLUSION OF THE MENTION OF CONVECTION FOR
MFE...AS ANOTHER ROUND OF SHOWERS/THUNDERSTORMS WILL LIKELY FORM
OVER THE MOUNTAINS OF NEIGHBORING MEXICO BEFORE MOVING OVER
PORTIONS OF DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY.
PREV DISCUSSION... /ISSUED 420 AM CDT THU APR 21 2016/
SHORT TERM /NOW THROUGH FRIDAY/...AN UNSETTLED WEATHER PATTERN
IS ANTICIPATED TO CONTINUE THROUGHOUT THE SHORT TERM PORTION OF
THE FORECAST. ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP
TODAY AS A RESULT OF A WEAK 500 MB DISTURBANCE RIDING WITHIN A
NEARLY WEST TO EAST MID-LEVEL FLOW OVERHEAD. INHERITED HIGH
TEMPERATURES APPEARED TOO COOL WHEN COMPARED TO YESTERDAY/S
OBSERVED HIGHS AND WERE RAISED ABOUT THREE DEGREES OVER THE ENTIRE
BRO CWFA. TONIGHT...THE APPROACH AND PASSAGE OF A MORE ROBUST 500
MB DISTURBANCE...AND THE SLOW SOUTHERLY MOVEMENT OF A WEAK COLD
FRONT THROUGH THE CRP CWFA... WILL GENERATE SCATTERED CONVECTION
OVER THE WESTERN TWO THIRDS OF THE BRO CWFA AND ISOLATED
PRECIPITATION WITHIN THE EASTERN THIRD. IN FACT...THE STORM
PREDICTION CENTER PLACES A MARGINAL RISK OF SEVERE WEATHER WITHIN
ZAPATA...JIM HOGG...BROOKS...AND KENEDY COUNTIES FOR TODAY AND
TONIGHT. HAVE NOT INCLUDED ANY MENTION OF STRONG WINDS OR LARGE
HAIL IN THE FORECAST...BUT WILL ADVISE SUCCESSIVE SHIFTS TO
MONITOR THIS TREND AND PLACE A MENTION OF ROUGH WEATHER IN THE
FORTHCOMING HAZARDOUS WEATHER OUTLOOK. MINIMUM TEMPERATURES FOR
TONIGHT WERE INCREASED A COUPLE OF NOTCHES ABOVE WHAT WAS
INHERITED. FOR FRIDAY...THE AFOREMENTIONED COLD FRONT STALLS
ROUGHLY ALONG THE BRO AND CRP CWFA BOUNDARY. POOLING MOISTURE IN
ADVANCE OF THIS SURFACE FEATURE WILL COMBINE WITH DAYTIME
HEATING...AND ENHANCED SEA BREEZE EFFECT...AND ANOTHER WEAK 500 MB
DISTURBANCE TO PRODUCE MAINLY SCATTERED CONVECTION.
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY NIGHT/...A RIDGE AXIS
WILL EXTEND NORTH FROM NORTHEAST MEXICO ACROSS THE HIGH PLAINS AND
INTO CANADA. HIGH PRESSURE WILL BE IN CONTROL FOR THE MOST PART...
WITH A STATIONARY FRONT LYING ACROSS SOUTH CENTRAL TEXAS. A MID
LEVEL LOW WILL BE ENTERING THE PACIFIC NORTHWEST WHILE ANOTHER
UPPER LOW OVER THE SOUTHERN BAHA PENINSULA EJECTS EAST AS A TROUGH
OVER THE AREA. AMPLE MOISTURE AND SUFFICIENT INSTABILITY WILL KEEP
THE THREAT OF SHOWERS AND TSTMS GOING THROUGH THE WEEKEND. THE ECMWF
IS MORE AGGRESSIVE WITH POPS FRIDAY NIGHT THROUGH SUNDAY. A MODEL
CONSENSUS STRUCK A MIDDLE GROUND. OTHER MODEL DIFFERENCES WERE MINOR.
HIGH PRESSURE OVER THE PLAINS WILL ADVANCE SOUTH WITH A WEAK COLD
FRONT MOVING INTO SOUTH TEXAS. THE FRONT WILL HAVE MINOR IMPACT HERE
THOUGH...SHIFTING LOCAL WINDS TO EAST ON FRI WITH LIMITED RAINFALL
AS ADVERTISED BY THE GFS.
HIGH PRESSURE WILL SHIFT EAST AND WINDS WILL VEER TO SOUTHEAST AGAIN
BY SATURDAY. THE ACCUMULATION OF RETURN MOISTURE AND THE REMAINS OF
THE OLD FRONTAL BOUNDARY JUST TO THE SOUTH WILL PROVIDE A FOCUS FOR
SHOWERS TO DEVELOP ACROSS THE PLAINS OF NORTHEAST MEXICO AS WELL AS
ALONG THE RIO GRANDE. TROUGHING...OR A DEEP POCKET OF LOWER MID
LEVEL HEIGHTS OVER NORTHWEST MEXICO...WILL ALSO KEEP A SOUTHWEST
FLOW GOING ALOFT...ADDING TO INSTABILITY OVER THE MEXICAN MOUNTAINS
AND PERHAPS FUELING SOME CONVECTION THERE FRIDAY NIGHT. THE TROUGH
WILL ADVANCE EAST SATURDAY...BECOMING MORE PROXIMATE TO THE RGV AND
MAINTAINING CONVECTIVE CHANCES FOR THE RGV THROUGH SATURDAY NIGHT.
MOISTURE WILL POOL OVER THE CWA...UNDER THE TROUGH MOVING OVERHEAD.
THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS MOVING EAST FROM MEXICO
TOWARD THE MID AND UPPER VALLEY WILL BE SATURDAY NIGHT.
ONCE THE TROUGH SHIFTS EAST OF THE REGION SUNDAY NIGHT...DRIER AIR
WILL FILTER IN WITH A WARMING AND CLEARING TREND MONDAY THROUGH
WEDNESDAY. AS THE TROUGH EXITS STAGE RIGHT SUNDAY...RAIN CHANCES
WILL DIMINISH BUT NOT QUITE END. THUS A CHANGE WILL BEGIN SUNDAY
NIGHT AND AFTER. A WEAK RIDGE WILL BUILD IN FROM THE WEST...AND
WITHOUT ANOTHER STRONG TROUGH UPSTREAM TO FOLLOW UP...THE FIRST HALF
OF NEXT WEEK LOOKS FAIRLY DRY FOR THE TIME BEING.
SHOULD SEE MOSTLY CLOUDY OR CLOUDY SKIES WEDNESDAY NIGHT THROUGH
SUNDAY NIGHT. TEMPS WILL BE CLOSE TO NORMAL THOUGH A LITTLE WARMER
THAN NORMAL AT NIGHT WITH THE EXTRA CLOUD COVER. WINDS WILL BE
MAINLY OUT OF THE SOFOR
THE REST OF TODAY. THE STORM PREDICTION CENTER /SPC/ HAS PLACE ALL
OF DEEP SOUTH TEXAS UNDER A MARGINAL RISK OF SEVERE WEATHER FOR
TODAY AND TONIGHT. THE MAIN THREATS FROM ANY STORMS THAT DEVELOP
THIS AFTERNOON INTO THIS EVENING WILL BE SMALL HAIL...GUSTY WINDS
AND LOCALLY HEAVY RAINFALL. MADE A QUICK UPDATE TO INCREASE POPS
AND TO MENTION SMALL HAIL...GUSTY WINDS AND HEAVY RAINFALL TO THE
WEATHER GRIDS. THE REST OF THE FORECAST LOOKS GOOD AND NO
ADDITIONAL CHANGES ARE NEEDED AT THIS TIME.UTHEAST.
MARINE...
NOW THROUGH FRIDAY...BUOY 42020 REPORTED SOUTH-SOUTHEAST WINDS
AROUND 16 KNOTS GUSTING TO AROUND 18 KNOTS WITH SEAS SLIGHTLY
UNDER 3.5 FEET WITH A PERIOD OF 7 SECONDS AT 03 CDT/08 UTC. HIGH
PRESSURE WILL PREVAIL OVER THE WESTERN GULF OF MEXICO UNTIL A WEAK
COLD FRONT APPROACHES FROM THE NORTH AND STALLS OVER THE MIDDLE
TEXAS COAST. LIGHT TO MODERATE WINDS AND LOW TO MODERATE SEAS WILL
PREVAIL AS A RESULT OF THIS WEATHER PATTERN...WITH NO SMALL CRAFT
EXERCISE CAUTION OR SMALL CRAFT ADVISORY ANTICIPATED.
FRIDAY NIGHT THROUGH MONDAY NIGHT...HIGH PRESSURE WILL SPREAD OVER
THE NORTHWEST GULF WITH A WEAK STATIONARY FRONT STRETCHING ALONG THE
UPPER TEXAS COAST AND ACROSS SOUTH CENTRAL TEXAS FRIDAY NIGHT. LIGHT
TO MODERATE EAST WINDS WILL PREVAIL LOCALLY THROUGH SATURDAY BEFORE
A LIGHT TO MODERATE SOUTHEAST WIND REDEVELOPS AND PERSISTS THROUGH
SUNDAY. WIND DIRECTION WILL VEER TO SOUTH SOUTHEAST OR SOUTH LATE
SUNDAY DUE TO A TRANSITING NORTHERN PLAINS LOW. WINDS AND SEAS WILL
INCREASE TO MODERATE.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
138 PM EDT THU APR 21 2016
.SYNOPSIS...
HIGH PRESSURE ALONG THE COAST WILL CONTINUE TO MOVE EAST AND
OFFSHORE TODAY. A WARM FRONT WILL PASS NORTHEAST THROUGH THE
REGION TONIGHT AHEAD OF AN APPROACHING COLD FRONT THAT WILL
REMAIN JUST WEST OF THE MOUNTAINS THROUGH EARLY FRIDAY. THIS
FRONT SHOULD PUSH EAST ACROSS THE AREA FRIDAY AFTERNOON BRINGING
A BETTER CHANCE OF MORE WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS
INTO FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1145 AM EDT THURSDAY...
ANOTHER MINOR UPDATE TO ACCOUNT FOR CLEARING STRATUS DECK IN EAST
AND ALSO DEEPER MIXING THAN PREVIOUSLY THOUGHT...LIKELY RESULTING
IN SOME STRONGER WIND GUSTS THROUGH THE AFTERNOON...IN THE 16 TO
24 MPH RANGE IN THE MOUNTAINS. TONGUE OF HIGHER DEW PT AIR HAS
PUSHED INTO THE NC FOOTHILLS BUT SHOULD MIX OUT OVER NEXT COUPLE
HOURS SO MADE SOME MINOR ADJUSTMENTS FOR THAT AS WELL. OTHERWISE
NO OTHER CHANGES AT THIS TIME.
PREV DISCUSSION AS OF 958 AM EDT THURSDAY...
BROKEN STRATUS DECK FROM MOIST SOUTHEASTERLY LOW LEVEL FLOW
BEGINNING TO ERODE QUICKLY WEST OF THE BLUE RIDGE...AND SATELLITE
AS WELL AS NEAR TERM MODELS SUGGEST THAT WILL CONTINUE FAIRLY
QUICKLY EAST OF BLUE RIDGE AS WELL. MEANWHILE...CLOUD COVER ACROSS
TN...KY...WV IS MAINLY MID TO HIGH AND FAIRLY THIN AND SO DO NOT
THINK THIS WILL HAVE MUCH IMPACT ON TEMPS. THUS BUMPED UP HIGH
TEMPS A FEW DEG AND HOPE THAT IS ENOUGH...AND ALSO REDUCED CLOUD
COVER SOMEWHAT.
HRRR AND SOME OTHER HI RES MODELS SUGGEST JUST BARELY ENOUGH
INSTABILITY IN CENTRAL NC AND VA TO GENERATE AN ISOLATED LATE
AFTERNOON SHOWER...BUT MOST LIKELY THIS WILL REMAIN JUST EAST OF
OUR FORECAST AREA...SO KEPT POPS BELOW 15 PERCENT BUT DID NUDGE
UPWARD AND WILL NEED TO MONITOR THIS AREA LATER TODAY FOR ANY
DEVELOPMENT IN CASE IT IS A LITTLE FARTHER WEST THAN EXPECTED.
OTHERWISE...MOST GUIDANCE CONTINUES TO SLOW DOWN APPROACH OF ANY
PRECIP AHEAD OF THE FRONT THAT IS CURRENTLY OVER NEAR THE
MISSISSIPPI RIVER. MAY NOT BE WORTH MENTIONING CHANCE POPS EVEN
IN FAR WEST UNTIL WELL AFTER MIDNIGHT. HRRR DOES SUGGEST SOME
SHOWERS ARRIVE IN FAR SW VA AROUND MIDNIGHT...BUT OTHER GUIDANCE
SHOWS THESE DISSIPATING AS THEY MOVE IN TO SOMEWHAT DRIER AIR.
THUS CONTINUED THE TREND OF REDUCING POPS THIS EVENING TO SLIGHT
CHC OR LESS...AND MAY NEED TO DO THIS EVEN MORE ON FUTURE UPDATES.
PREV DISCUSSION AS OF 222 AM EDT THURSDAY...
MOISTURE TO GRADUALLY RETURN ACROSS THE REGION OVER THE NEXT 24 HOURS
AS THE SURFACE-85H FLOW QUICKLY VEERS FROM SE THIS MORNING TO SW WHILE
INCREASING THIS AFTERNOON/OVERNIGHT AHEAD OF THE COLD FRONT TO THE
WEST. THIS LOW LOW LEVEL SOUTH/SE FLOW THIS MORNING WILL AGAIN ADVECT
LOW CLOUDS NOW OVER NORTH CAROLINA INTO AREAS MAINLY ALONG/EAST OF THE
BLUE RIDGE BEFORE GETTING BOOTED EAST THIS AFTERNOON AS THE FLOW TURNS
MORE SW. COULD EVEN SEE A SPOTTY LIGHT SHOWER OR SPOT OR TWO OF DRIZZLE
SOUTHERN BLUE RIDGE AND POINTS EAST THIS MORNING SO INCLUDED SOME
MENTION TO INIT. LATEST GUIDANCE INDICATES THAT MOST OF THE LOW CLOUDS
SHOULD BE EAST OF THE CWA BY MID AFTERNOON ALLOWING DEEPENING WARM
ADVECTION TO RETURN UNDER MOSTLY SHEARED MID/HIGH CLOUDS WITH
CONVECTION ALONG THE COLD FRONT TO THE WEST. MOISTURE ALONG WITH
LIFT/INSTABILITY APPEARS TOO LACKING TO PRODUCE MUCH IN THE WAY OF
SHOWERS THIS AFTERNOON DESPITE TEMPS WARMING BACK INTO THE 70S. THUS
CUTTING BACK ON POPS OUTSIDE OF THE FAR SW LATE WITH THINGS
TURNING BREEZY/MILD UNDER PARTLY SUNNY SKIES PER DRY AIR ALOFT.
WEAK RESIDUAL WARM FRONT WILL LIFT NE THROUGH THE REGION OVERNIGHT
RESULTING IN ADDED LOW LEVEL MOISTURE RETURN AS DEWPOINTS LOOK TO SURGE
INTO THE 50S. HOWEVER MOISTURE DEPTH WILL BE SHALLOW AND STILL LIMITED
BY MID LEVEL DRY AIR...SO POPS QUITE IFFY DURING THE EVENING AND MOSTLY
CONFINED TO THE FAR WEST AT BEST WHERE WILL KEEP SOME LOW CHANCE POPS.
UPPER LOW ACROSS THE MIDWEST SHOULD DRIFT MORE EASTWARD LATE TONIGHT
ALLOWING THE TRAILING SURFACE COLD FRONT TO WORK INTO THE OHIO/TN
VALLEY REGION BY DAYBREAK. GUIDANCE SUGGESTS POSSIBLE MULTIPLE BANDS OR
CLUSTERS OF DISORGANIZED SHOWERS LIKELY WITHIN THE PRE-FRONTAL AXIS OF
DEEP MOISTURE THAT LOOK TO PUSH OUT TO ALONG THE BLUE RIDGE. AGAIN THE
GFS REMAINS THE FASTEST WITH THE 00Z ECMWF MUCH SLOWER WITH SHOWERS
JUST TOUCHING THE FAR WESTERN COUNTIES BY 12Z. SINCE THE REMAINDER OF
THE SOLUTIONS AS WELL AS THE LATEST SREF SHOWING AT LEAST SOME SHOWERS
ACROSS THE MOUNTAINS...WILL CARRY MID LEVEL CHANCE POPS WEST OVERNIGHT
AND LOWER POPS EAST. OTRW BECOMING MOSTLY CLOUDY BUT QUITE MILD UNDER
SW BREEZES AND INCREASING MOISTURE WITH LOWS ONLY 50S TO AROUND 60 IN
SPOTS.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 235 AM EDT THURSDAY...
A COLD FRONT WILL MOVE EAST ACROSS THE REGION FRIDAY INTO FRIDAY
NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD AND ALONG THE
FRONT. SURFACE BASED CAPE VARIES AVERAGE AROUND 500-1000 J/KG AND
SURFACE BASED LIFTED INDICES ARE AROUND -2. THE DAY TWO CONVECTIVE
OUTLOOK PLACES OUR ENTIRE FORECAST AREA IN GENERAL THUNDERSTORMS
WITH A MARGINAL THREAT TO OUR SOUTH ACROSS ALABAMA AND GEORGIA.
HIGH TEMPERATURES FRIDAY WILL RANGE FROM THE MID 60S IN THE
MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
THE FRONT WILL EXIT THE AREA FRIDAY NIGHT WITH THE GREATEST
ABUNDANCE OF LINGERING SHOWERS ACROSS THE SOUTHEAST PORTION OF THE
AREA. LOW TEMPERATURES FRIDAY NIGHT WILL VARY FROM THE MID 40S IN
THE NORTHWEST MOUNTAINS TO THE MID 50S IN THE PIEDMONT.
ISOLATED SHOWERS WILL ALSO BE ASSOCIATED WITH PASSAGE OF THE 850 MB
FRONT AND INCREASING NORTHWEST FLOW ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA. THIS SHOWERS WILL LINGER SATURDAY MORNING. HIGH PRESSURE
WILL BUILD INTO THE AREA BY SATURDAY AFTERNOON BEHIND THE DEPARTING
COLD FRONT. HIGH TEMPERATURES SATURDAY WILL REACH READINGS FROM THE
UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE PIEDMONT.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS OUR AREA SATURDAY NIGHT
INTO SUNDAY. LOW TEMPERATURES SATURDAY WILL DROP TO AROUND 40 IN THE
COLDER MOUNTAINS VALLEYS TO NEAR 50 DEGREES IN THE PIEDMONT. SUNDAY
HIGH TEMPERATURES WILL WARM TO 70 DEGREES IN THE MOUNTAINS AND
APPROACH 80 DEGREES IN THE PIEDMONT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...
AN AXIS OF HIGH PRESSURE WILL SLOWLY PROGRESS ACROSS THE REGION INTO
EARLY NEXT WEEK. DRY AND PROGRESSIVELY MILDER CONDITIONS
ARE EXPECTED.
MONDAY NIGHT INTO WEDNESDAY...GUIDANCE IS VARIABLE REGARDING THE
APPROACH AND POSSIBLE PASSAGE OF A COLD FRONT. THE GFS IS MORE
PROGRESSIVE WHILE THE ECMWF IS SLOWER BY AROUND HALF OF A DAY.
ALSO...DIFFERENCES EXIST REGARDING A POTENTIAL SOUTHERLY WAVE MOVING
NORTHEAST ALONG THE FRONT ON WEDNESDAY...THAT BUCKLES THE FEATURE
BACK INTO OUR REGION. OUR FORECAST SOLUTION WILL REFLECT CLOSER TO
THAT OF THE ECMWF THAT HAS A SLOWER PROGRESSION...AND ALLOWS FOR
GREATER IMPACT FROM THE SOUTHERLY WAVE AND MORE ROBUST DAY OF
PRECIPITATION AND COOLER CONDITIONS ON WEDNESDAY.
TEMPERATURES WILL TREND MILDER DURING THIS PORTION OF THE FORECAST
THROUGH TUESDAY WHEN READINGS WILL AVERAGE FIVE TO TEN DEGREES ABOVE
NORMAL. WEDNESDAY IS EXPECTED TO BE COOLER WITH CLOUDS AND
PRECIPITATION ACROSS THE AREA.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 130 PM EDT THURSDAY...
MVFR HAVE ERODED ACROSS THE AREA. LOCAL NWS RADAR SHOWED ISOLATED
SHOWERS HAVE DEVELOPED ALONG THE WEST VIRGINIA/VIRGINIA BORDER.
SHORT TERM MODELS ALSO SUGGEST SHOWERS MAY DEVELOP THIS AFTERNOON
AROUND KDAN AND TO THE EAST AND SOUTH. EXPECT MIXING TO CONTINUE
THIS AFTERNOON WITH GUSTS FROM THE SOUTHWEST UP TO 25 KNOTS.
THE BAND OF SHOWERS FROM OHIO INTO WESTERN TENNESSEE WILL MOVE
TONIGHT...REACHING THE MOUNTAINS AROUND MIDNIGHT AND PROGRESSING
EAST ACROSS THE REGION THROUGH FRIDAY MORNING. ONLY MEDIUM
CONFIDENCE ON THE TIMING OF THIS PRECIPITATION WITH THE MODELS
TRENDS SLOWING DOWN THE ARRIVAL TIME OF THE SHOWERS. THE UPSTREAM
COLD FRONT. SOME IFR CEILINGS ARE POSSIBLE IN THE
MOUNTAINS...ESPECIALLY AT KLWB AND KBLF FRIDAY AFTERNOON BUT
CONFIDENCE IN OCCURRENCE IS LOW.
EXTENDED AVIATION DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG WITH A COLD FRONT OVER
THE MIDWEST STATES WILL BEGIN TO BRING AN INCREASE IN DEEPER
MOISTURE AND COULD RESULT IN PERIODS OF SUB-VFR CEILINGS AS WELL
AS SHOWERS AND ISOLATED THUNDERSTORMS FRIDAY NIGHT AND SATURDAY
MORNING....WITH BEST PROBABILITY OF MVFR CONDITIONS IN THE
MOUNTAINS.
VFR SHOULD RETURN BEHIND THE FRONT FOR SUNDAY AND MONDAY AS HIGH
PRESSURE CROSSES THE REGION. HOWEVER SOME LOWER CIGS MIGHT
REDEVELOP ACROSS THE MOUNTAINS BY SUNDAY AS LIGHT EASTERLY FLOW
SETS UP UNDER ANOTHER WEAK WEDGE WHICH SHOULD FADE BY EARLY NEXT
WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SK
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
345 PM CDT THU APR 21 2016
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 344 PM CDT THU APR 21 2016
AT 3 PM...SCATTERED SHOWERS WERE FOUND ACROSS CLARK COUNTY IN
NORTH-CENTRAL WISCONSIN AND NORTHEAST IOWA. BOTH OF THESE WERE
LOCATED ALONG A BAND OF 900 TO 800 MB FRONTOGENESIS. THERE WERE
REPORTS OF A WALL CLOUD AND PEA SIZE HAIL IN DAVENPORT/S FORECAST
AREA. THIS WAS OCCURRING IN AN AREA WHERE THE RAP WAS HIGHLIGHTING
A HIGH POTENTIAL FOR NON SUPERCELL TORNADO PARAMETER /NST/.
THROUGH 21.23Z...THE RAP IS HIGHLIGHTING ANOTHER STRONG AREA OF
NST ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. THERE IS A
STATIONARY BOUNDARY IN THIS AREA. HOWEVER THE RAP IS 5 TO 8F TOO
HIGH WITH ITS SURFACE DEW POINTS...THEREFORE...ITS CAPES ARE TOO
HIGH. THIS IS LIKELY ENHANCING THE NST VALUE TOO MUCH. AS A
RESULT...WE ARE JUST GOING TO CONTINUE TO MONITOR THIS AREA
CLOSELY AND NOT ISSUE A SPECIAL WEATHER STATEMENT AT THIS TIME.
FOR THIS EVENING...THE 21.12Z AND 21.18Z MODELS CONTINUE TO SHOW
THAT BOTH OF THE 900 TO 800 MB FRONTOGENESIS BANDS WILL SLOWLY
MOVE SOUTHEAST AND WEAKEN. AT THE SAME TIME...THE SURFACE BASED
CAPES AND 900 TO 850 MB LAPSE RATES WILL BE WEAKENING. AS THIS
OCCURS...THE SHOWERS WILL RAPIDLY DISSIPATE BETWEEN 22.03Z AND
22.06Z.
ON FRIDAY MORNING...TEMPERATURES WILL DROP INTO THE MID-30S IN
TAYLOR COUNTY. WHILE THE TEMPERATURES WILL BE COOL FOR THE
POTENTIAL OF SCATTERED FROST...THERE WILL STILL BE A 2 TO 3F
TEMPERATURE-DEW POINT DEPRESSIONS AND THE SURFACE WINDS WILL BE IN
THE 5 TO 10 MPH RANGE. THIS SHOULD DETER THE DEVELOPMENT OF FROST
IN THAT AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 PM CDT THU APR 21 2016
ON FRIDAY NIGHT THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS.
THIS WILL ALLOW THE LOW TEMPERATURES TO FALL INTO THE MID 30S IN
CENTRAL WISCONSIN. THIS MAY RESULT IN SOME PATCHY FROST IN THIS
AREA. WE WILL HAVE TO WATCH THIS AREA CLOSELY FOR A POTENTIAL
FROST ADVISORY.
FROM SATURDAY NIGHT THROUGH MONDAY...AN UPPER LEVEL LOW WILL MOVE
SOUTHEAST THROUGH THE REGION. ON SUNDAY AFTERNOON...THE 0-4 KM
CAPES WILL CLIMB UP TO 750 J/KG SOUTH OF INTERSTATE 90 CORRIDOR
AND THE 0-6 KM SHEAR WILL CLIMB UP TO 45 KNOTS. THIS MAY RESULT IN
THE DEVELOPMENT OF A FEW SUPERCELLS AHEAD OF THE COLD FRONT IN
NORTHEAST IOWA. WE WILL HAVE TO WATCH THIS PERIOD CLOSELY.
FROM TUESDAY NIGHT INTO WEDNESDAY...ANOTHER UPPER LEVEL LOW WILL
MOVE SOUTHEAST THROUGH THE REGION. THERE CONTINUES TO BE DEEP
SHEAR LOCATED SOUTH OF INTERSTATE 94. HOWEVER THE CAPES ARE ONLY
UP TO 500 J/KG. THIS CAPE WILL BE A LIMITING FACTOR FOR ANY THREAT
OF SEVERE WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1232 PM CDT THU APR 21 2016
LOW PRESSURE TRACKING EAST ACROSS THE AREA TODAY WAS PRODUCING
SCATTERED-BROKEN MAINLY VFR CUMULUS. AS OF NOON THERE WERE NO SHRA
IN THE AREA ON RADAR...BUT STILL EXPECTING WIDELY SCATTERED SHRA
ACTIVITY GOING INTO THIS AFTERNOON/EVENING. SATELLITE WAS SHOWING
SOME MVFR/IFR STRATOCUMULUS UPSTREAM ACROSS NORTHERN MN. THIS
CLOUD GETS PULLED SOUTHEAST ACROSS OUR AREA TONIGHT INTO FRIDAY
MORNING...SCATTERING OUT BY LATER FRIDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS