Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/24/14
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
320 PM MST THU MAY 22 2014
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
AN AREA OF LOW PRESSURE TRACKING SLOWLY ACROSS THE DESERT SOUTHWEST
WILL LEAD TO A SLIGHT CHANCE OF THUNDERSTORMS FRIDAY ACROSS THE
REGION. STORM CHANCES WILL BE LIMITED TO THE HIGHER TERRAIN OF
SOUTH-CENTRAL ARIZONA ON SATURDAY. A SLOW WARMING TREND WILL BEGIN
OVER SOUTHEAST CALIFORNIA FRIDAY AND EXPAND EASTWARD OVER THE
WEEKEND. ANTICIPATE TEMPERATURES AT LEAST A FEW DEGREES ABOVE NORMAL
BY MONDAY WITH LITTLE CHANGE THROUGH THURSDAY.
&&
.DISCUSSION...
REST OF TODAY THROUGH SUNDAY...
SCATTERED THUNDERSTORMS HAVE DEVELOPED THIS AFTERNOON OVER SOUTHERN
CALIFORNIA...MAINLY OVER THE HIGHER MOUNTAINS AND
DESERTS...INCLUDING EASTERN RIVERSIDE AND FAR WESTERN IMPERIAL
COUNTIES. LESSER ACTIVITY HAS ALSO OCCURRED OVER THE EASTERN THIRD
OF ARIZONA...JUST BRUSHING EASTERN PORTIONS OF GILA COUNTY. FOR OUR
AREA THE MOST SIGNIFICANT ACTIVITY HAS BEEN OVER EASTERN RIVERSIDE
COUNTY INCLUDING JOSHUA TREE NATIONAL PARK. THE STORMS ARE DUE TO AN
UPPER LOW CENTERED OVER THE MOHAVE DESERT BRINGING SOME MOISTURE AND
DESTABILIZATION WITH IT. AN EMBEDDED VORT MAX ON THE SOUTHERN END OF
THE SYSTEM MAY ALSO BE PROVIDING SOME QG FORCING AS WELL. HI-RES
MODELS INCLUDING THE HRRR HAVE DONE A GOOD JOB DEPICTING THE
CONVECTION. PRECIP PRODUCTION TURNS OUT TO HAVE BEEN BETTER THAN
ANTICIPATED. HAVE NOT HAD ANY DIRECT REPORTS OF FLOODING OR VERY
STRONG WINDS FOR OUR AREA BUT FLASH FLOODING WAS REPORTED IN THE SAN
DIEGO COUNTY DESERTS NEAR BORREGO SPRINGS. QUITE IMPRESSIVE GIVEN
THE MODEST PWAT VALUES. BREEZY CONDITIONS CONTINUE OVER PORTIONS OF
SOUTH-CENTRAL ARIZONA INCLUDING NORTHERN PINAL COUNTY AND THE HIGHER
TERRAIN EAST OF PHOENIX. COULD SEE SOME LOCALIZED DUST OVER OUR MOST
DUST PRONE AREAS. THUNDERSTORM ACTIVITY WILL TRAIL OFF THIS EVENING
AS SURFACE HEATING IS LOST. NOT INCONCEIVABLE THAT A STRAY SHOWER
POPS UP OVERNIGHT AS THE VORT MAX MOVES EASTWARD. THE LOW CENTER IS
EXPECTED TO SHIFT EASTWARD A BIT FRIDAY. THE FOCUS APPEARS TO BE
AREAS ABOVE 2000 FT IN ELEVATION OVER LA PAZ AND WESTERN MARICOPA
COUNTY. INTERESTINGLY...THE MODELS ALSO TEND TO AGREE THAT THE
HIGHER TERRAIN EAST OF PHOENIX WILL NOT SEE MUCH ACTIVITY. HELD ON
TO THE SLIGHT CHANCE POPS THERE BUT EXPANDED THE SLIGHT CHANCES TO
THE LOWER ELEVATIONS ACROSS THE WHOLE FORECAST AREA. SOUTHEAST
CALIFORNIA SHOULD BE MORE STABLE FRIDAY AND THUS LESS ACTIVE BUT
STILL KEEPING A SLIGHT CHANCE. SATURDAY...THE LOW CONTINUES MOVING
SLOWLY EAST AND THUS BEST INSTABILITY WILL BE OVER EASTERN HALF OF
ARIZONA. MODELS AGREE THAT FOR OUR AREA...THE HIGHER TERRAIN EAST OF
PHOENIX WILL HAVE THE BEST CHANCE OF CONVECTION...WITH SOME SPILL-
OVER INTO FAR NORTHERN MARICOPA COUNTY INCLUDING NORTHERN PORTIONS
OF THE PHOENIX AREA. ON SUNDAY...THE SYSTEM IS MOSTLY INTO NEW
MEXICO AND THERE IS ONLY A LINGERING VERY SLIGHT CHANCE OF
CONVECTION OVER SOUTHEAST GILA COUNTY. AS FOR TEMPERATURES...A
WARMING TREND WILL BEGIN FRIDAY OVER SOUTHEAST
CALIFORNIA...EXPANDING TO SOUTHWEST ARIZONA SATURDAY...THEN REACHING
SOUTH-CENTRAL ARIZONA SUNDAY.
MONDAY THROUGH THURSDAY...
THE UPPER LOW WILL EVENTUALLY MOVE BACK INTO THE MEAN STORM FLOW AND
CLEAR OUT OF THE SOUTHWEST STATES BY LATE MONDAY...LEAVING SUBTLE
RIDGE HEIGHTS OVERHEAD. UPPER LEVEL HEIGHTS QUICKLY BUILD BACK INTO
THE UPPER 580DM RANGE...WARMING TEMPERATURES BACK TO NORMAL AND THEN
ABOVE NORMAL READINGS BY EARLY NEXT WEEK. RIDGE HEIGHTS LOOK TO PEAK
BY TUESDAY/WEDNESDAY AS THE RIDGE AXIS MOVES INTO NEW MEXICO...WHILE
LONGWAVE TROUGHING DEVELOPS OFF THE WEST COAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...ISOLATED
CONVECTION IS EXPECTED TO THIS AFTERNOON INTO EARLY EVENING HOURS
WELL EAST OF THE PHOENIX TERMINALS ACROSS EASTERN AZ. ACROSS THE
PHOENIX AREA...AFTERNOON BREEZINESS AGAIN EXPECTED UNTIL 06Z WITH
OCCASIONAL GUSTS AS HIGH AS 20 KT. A RETURN TO LIGHTER DOWNSLOPE
EASTERLY FLOW IS EXPECTED AFTER 08Z FRIDAY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
ISOLATED THUNDERSTORM CHANCES WILL CONTINUE THROUGH 06Z FRIDAY
ACROSS SOUTHEASTERN CA. STORMS ARE EXPECTED TO REMAIN CONFINED TO
THE HIGHER TERRAIN EAST OF SAN DIEGO AND TOWARDS JOSHUA TREE
NATIONAL PARK AND ALONG INTERSTATE 10 TOWARDS BLYTHE. THERE IS A
REMOTE POSSIBILITY THAT AN ISOLATED CELL WILL AFFECT KIPL/KBLH WITH
BRIEF GUSTY WINDS...AND CONFIDENCE IS LOW SO NO MENTION IN THE TAFS
AT THIS TIME. OTHERWISE...WINDS WILL PREDOMINATELY REMAIN OUT OF THE
SOUTH AND WEST...WITH GUSTS UP TO 20 KT INTO THIS EVENING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
THE SLOW MOVING LOW PRESSURE SYSTEM WILL FINALLY MAKE AN EXIT FROM
THE REGION MOVING EASTWARD. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ACROSS NORTHEASTERN AZ THROUGH
SUNDAY...THOUGH RAIN CHANCES WILL BE CONSIDERABLY LESS ACROSS THE
LOWER DESERTS. ISOLATED DRY THUNDERSTORMS WILL ALSO REMAIN A THREAT
AS WELL...PARTICULARLY ACROSS THE HIGHER TERRAIN NORTH AND EAST OF
PHOENIX...AS THE AIR MASS WILL REMAIN VERY DRY WITH LOW HUMIDITY
VALUES. WINDS WILL GENERALLY REMAIN LIGHT...EXCEPT IN THE VICINITY
OF THUNDERSTORMS. A WARMING AND DRYING TREND IS EXPECTED WITH ABOVE
AVERAGE TEMPERATURES LIKELY BY MONDAY AND CONTINUING THROUGH MIDWEEK.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/NOLTE
AVIATION....DEWEY
FIRE WEATHER...DEWEY/HIRSCH
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
310 PM MST THU MAY 22 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE TRACKING SLOWLY ACROSS THE DESERT SOUTHWEST
WILL LEAD TO A SLIGHT CHANCE OF THUNDERSTORMS FRIDAY ACROSS THE
REGION. STORM CHANCES WILL BE LIMITED TO THE HIGHER TERRAIN OF
SOUTH-CENTRAL ARIZONA ON SATURDAY. A SLOW WARMING TREND WILL BEGIN
OVER SOUTHEAST CALIFORNIA FRIDAY AND EXPAND EASTWARD OVER THE
WEEKEND. ANTICIPATE TEMPERATURES AT LEAST A FEW DEGREES ABOVE NORMAL
BY MONDAY WITH LITTLE CHANGE THROUGH THURSDAY.
&&
.DISCUSSION...
REST OF TODAY THROUGH SUNDAY...
SCATTERED THUNDERSTORMS HAVE DEVELOPED THIS AFTERNOON OVER SOUTHERN
CALIFORNIA...MAINLY OVER THE HIGHER MOUNTAINS AND
DESERTS...INCLUDING EASTERN RIVERSIDE AND FAR WESTERN IMPERIAL
COUNTIES. LESSER ACTIVITY HAS ALSO OCCURRED OVER THE EASTERN THIRD
OF ARIZONA...JUST BRUSHING EASTERN PORTIONS OF GILA COUNTY. FOR OUR
AREA THE MOST SIGNIFICANT ACTIVITY HAS BEEN OVER EASTERN RIVERSIDE
COUNTY INCLUDING JOSHUA TREE NATIONAL PARK. THE STORMS ARE DUE TO AN
UPPER LOW CENTERED OVER THE MOHAVE DESERT BRINGING SOME MOISTURE AND
DESTABILIZATION WITH IT. AN EMBEDDED VORT MAX ON THE SOUTHERN END OF
THE SYSTEM MAY ALSO BE PROVIDING SOME QG FORCING AS WELL. HI-RES
MODELS INCLUDING THE HRRR HAVE DONE A GOOD JOB DEPICTING THE
CONVECTION. PRECIP PRODUCTION TURNS OUT TO HAVE BEEN BETTER THAN
ANTICIPATED. HAVE NOT HAD ANY DIRECT REPORTS OF FLOODING OR VERY
STRONG WINDS FOR OUR AREA BUT FLASH FLOODING WAS REPORTED IN THE SAN
DIEGO COUNTY DESERTS NEAR BORREGO SPRINGS. QUITE IMPRESSIVE GIVEN
THE MODEST PWAT VALUES. BREEZY CONDITIONS CONTINUE OVER PORTIONS OF
SOUTH-CENTRAL ARIZONA INCLUDING NORTHERN PINAL COUNTY AND THE HIGHER
TERRAIN EAST OF PHOENIX. COULD SEE SOME LOCALIZED DUST OVER OUR MOST
DUST PRONE AREAS. THUNDERSTORM ACTIVITY WILL TRAIL OFF THIS EVENING
AS SURFACE HEATING IS LOST. NOT INCONCEIVABLE THAT A STRAY SHOWER
POPS UP OVERNIGHT AS THE VORT MAX MOVES EASTWARD. THE LOW CENTER IS
EXPECTED TO SHIFT EASTWARD A BIT FRIDAY. THE FOCUS APPEARS TO BE
AREAS ABOVE 2000 FT IN ELEVATION OVER LA PAZ AND WESTERN MARICOPA
COUNTY. INTERESTINGLY...THE MODELS ALSO TEND TO AGREE THAT THE
HIGHER TERRAIN EAST OF PHOENIX WILL NOT SEE MUCH ACTIVITY. HELD ON
TO THE SLIGHT CHANCE POPS THERE BUT EXPANDED THE SLIGHT CHANCES TO
THE LOWER ELEVATIONS ACROSS THE WHOLE FORECAST AREA. SOUTHEAST
CALIFORNIA SHOULD BE MORE STABLE FRIDAY AND THUS LESS ACTIVE BUT
STILL KEEPING A SLIGHT CHANCE. SATURDAY...THE LOW CONTINUES MOVING
SLOWLY EAST AND THUS BEST INSTABILITY WILL BE OVER EASTERN HALF OF
ARIZONA. MODELS AGREE THAT FOR OUR AREA...THE HIGHER TERRAIN EAST OF
PHOENIX WILL HAVE THE BEST CHANCE OF CONVECTION...WITH SOME SPILL-
OVER INTO FAR NORTHERN MARICOPA COUNTY INCLUDING NORTHERN PORTIONS
OF THE PHOENIX AREA. ON SUNDAY...THE SYSTEM IS MOSTLY INTO NEW
MEXICO AND THERE IS ONLY A LINGERING VERY SLIGHT CHANCE OF
CONVECTION OVER SOUTHEAST GILA COUNTY. AS FOR TEMPERATURES...A
WARMING TREND WILL BEGIN FRIDAY OVER SOUTHEAST
CALIFORNIA...EXPANDING TO SOUTHWEST ARIZONA SATURDAY...THEN REACHING
SOUTH-CENTRAL ARIZONA SUNDAY.
MONDAY THROUGH THURSDAY...
THE UPPER LOW WILL EVENTUALLY MOVE BACK INTO THE MEAN STORM FLOW AND
CLEAR OUT OF THE SOUTHWEST STATES BY LATE MONDAY...LEAVING SUBTLE
RIDGE HEIGHTS OVERHEAD. UPPER LEVEL HEIGHTS QUICKLY BUILD BACK INTO
THE UPPER 580DM RANGE...WARMING TEMPERATURES BACK TO NORMAL AND THEN
ABOVE NORMAL READINGS BY EARLY NEXT WEEK. RIDGE HEIGHTS LOOK TO PEAK
BY TUESDAY/WEDNESDAY AS THE RIDGE AXIS MOVES INTO NEW MEXICO...WHILE
LONGWAVE TROUGHING DEVELOPS OFF THE WEST COAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
ISOLATED CONVECTION IS EXPECTED TO DEVELOP THIS AFTERNOON WELL EAST
OF THE PHOENIX TERMINALS ACROSS EASTERN AZ. ACROSS THE PHOENIX
AREA...AFTERNOON BREEZINESS WILL AGAIN BE PREVALENT WITH OCCASIONAL
GUSTS AS HIGH AS 20 KT. A RETURN TO LIGHTER DOWNSLOPE EASTERLY FLOW
IS EXPECTED BETWEEN 06Z AND 08Z FRIDAY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
ISOLATED THUNDERSTORMS ARE LIKELY ACROSS SOUTHEASTERN CA THIS
AFTERNOON AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. STORMS WILL
GENERALLY REMAIN CONFINED TO THE HIGHER TERRAIN EAST OF SAN DIEGO
AND TOWARDS JOSHUA TREE NATIONAL PARK. HOWEVER...THERE IS A REMOTE
POSSIBILITY THAT AN ISOLATED CELL WILL AFFECT KIPL/KBLH WITH BRIEF
GUSTY WINDS. OTHERWISE...WINDS WILL PREDOMINATELY REMAIN OUT OF THE
SOUTH AND WEST...WITH GUSTS UP TO 20 KT LATE THIS AFTERNOON AND THIS
EVENING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
A LOW PRESSURE SYSTEM WILL CONTINUE MOVING SLOWLY EASTWARD THROUGH
AZ THIS WEEKEND. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE ACROSS NORTHEASTERN AZ THROUGH SUNDAY...THOUGH RAIN
CHANCES WILL BE CONSIDERABLY LESS ACROSS THE LOWER DESERTS. ISOLATED
DRY THUNDERSTORMS WILL ALSO REMAIN A THREAT AS WELL...PARTICULARLY
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX. WINDS WILL
GENERALLY REMAIN LIGHT...EXCEPT IN THE VICINITY OF THUNDERSTORMS.
AFTER SOMEWHAT COOLER CONDITIONS SATURDAY...A WARMING AND DRYING
TREND IS EXPECTED WITH ABOVE AVERAGE TEMPERATURES LIKELY BY MONDAY
AND CONTINUING THROUGH MIDWEEK.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/NOLTE
AVIATION....HIRSCH
FIRE WEATHER...HIRSCH
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1005 AM MST THU MAY 22 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL SLOWLY MOVE THROUGH THE DESERT SOUTHWEST
TODAY THROUGH THE EARLY WEEKEND...KEEPING DAYTIME HIGHS BELOW NORMAL.
THERE WILL BE A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS
OVER THE HIGHER TERRAIN OF THE FORECAST AREA AS THE LOW MOVES THROUGH
THE REGION. A GRADUAL WARMING TREND WILL BEGIN FROM WEST TO EAST
WITH ABOVE NORMAL TEMPERATURES RETURNING BY EARLY NEXT WEEK.
&&
.DISCUSSION...
UPPER LOW CENTERED OVER THE MOHAVE DESERT REGION OF CALIFORNIA AND
NEVADA THIS MORNING. TWO VORT LOBES ARE EVIDENT IN THE WATER VAPOR
IMAGERY...NORTH AND SOUTH OF THE SYSTEM CENTER. BLENDED TPW IMAGERY
SHOWS OVER 2/3 INCH OF PWATER NEAR AND WEST OF THE LOWER COLORADO
RIVER VALLEY. ISOLATED CONVECTION HAS ALREADY STARTED ON/NEAR MT.
SAN GORGONIO WHICH IS NOT FAR WEST/NORTHWEST OF JOSHUA TREE NATIONAL
PARK. 12Z NCEP MODELS ARE MORE AGGRESSIVE THAN SOME PREVIOUS RUNS
WITH THE PRECIP OVER SOUTHERN CALIFORNIA TODAY...MAINLY HUGGING THE
HIGHER TERRAIN. HI RES MODELS INCLUDING HRRR AND LOCAL WRF AND NMM
ALSO DEPICT CONVECTION DEVELOPING OVER OUR PORTION OF CALIFORNIA
TODAY. IN FACT...SOME ADDITIONAL UPWARD ADJUSTMENTS TO THE POPS MAY
NEED TO BE MADE IN EASTERN RIVERSIDE COUNTY AND WESTERN IMPERIAL
COUNTY FOR TODAY. TO THE EAST...OVER THE EASTERN THIRD OF ARIZONA
INCLUDING SOUTHERN GILA COUNTY...MODELS ARE NOT AS ENTHUSIASTIC WITH
CONVECTION BUT STILL DEPICT SOME MODEST DEVELOPMENT. ANTICIPATE
SOMETHING OF A REPEAT FOR FRIDAY THOUGH CONVECTION EXCEPT FOR
SOMEWHAT OF AN EASTERN SHIFT IN THE ISOLATED/SCATTERED CONVECTION.
MORE LATER.
&&
.PREVIOUS DISCUSSION ISSUED 257 AM...
SKIES OVERNIGHT HAVE REMAINED MOSTLY CLEAR...WITH ONLY A FEW CU
ACROSS FAR EASTERN GILA COUNTY AND EVEN FEWER WISPS OF CIRRUS OUT
OVER THE SOUTHEAST CALIFORNIA DESERTS. BROAD UPPER LOW CURRENTLY
CIRCULATING TO OUR NORTHWEST WITH ONE IN A SERIES OF VORT MAXES
ROTATING AROUND THE BASE JUST MOVING INLAND OVER NORTHERN BAJA PER
WATER VAPOR IMAGERY. IN THE WAKE OF WEDNESDAY`S SLOW FRONTAL
PASSAGE...A SLIGHTER COOLER AIR MASS WAS OBSERVED OVER THE FORECAST
AREA ON EVENING RAOBS. EXPECT LITTLE CHANGE IN TODAY`S HIGH
TEMPERATURES FROM WEDNESDAY`S WITH VERY LITTLE WAA DESPITE SOUTHWEST
FLOW THROUGH THE COLUMN.
THE UPPER LOW WILL SLOWLY DIG INTO CALIFORNIA TODAY AND EVENTUALLY
BEGIN A SLOW TRANSITION EASTWARD IN ARIZONA FOR FRIDAY AND SATURDAY.
PRECIPITATION CHANCES WERE INCREASED OVER THE MOUNTAINS OF JTNP AND
DOWN INTO THE NEARBY SOUTHEAST CALIFORNIA DESERTS FOR THIS AFTERNOON
AND EVENING AS THE LOW CENTER AND COOL POOL ALOFT MOVES RIGHT THROUGH
THAT REGION. BLENDED TPW SATELLITE PLOT SHOWING ANYWHERE FROM 0.60 TO
0.80 INCHES OVER SOUTHERN CALIFORNIA...HOWEVER SOUNDING PROFILES KEEP
MOST OF THAT MOISTURE THROUGH THE MID-LEVELS WITH DRY SUB-CLOUD
LAYERS...LEADING TO STRONG GUSTY WINDS THE BIGGER THREAT THAN WETTING
RAINS. EXPECT THE BULK OF THE ACTIVITY TO BE DIURNALLY DRIVEN...SO
OUTSIDE OF SOME LINGERING CLOUDS OVERNIGHT...SHOWER/THUNDERSHOWER
ACTIVITY SHOULD DISSIPATE AFTER SUNSET ACROSS SOUTHEAST CALIFORNIA.
BY FRIDAY...THE LOW CIRC CENTER AND 500MB/700MB COOL POOL WILL MOVE
FULLY INTO ARIZONA. ADDITIONAL VORT ENERGY AND DIFLUENT MOTION
THROUGH THE ATMO UPPER LAYERS KEPT AT LEAST SLIGHT CHANCES GOING OVER
THE SOUTH-CENTRAL ARIZONA HIGH TERRAIN...INCLUDING PORTIONS OF
WESTERN MARICOPA COUNTY. MOISTURE AVAILABILITY REMAINS LIMITED...WITH
FORECAST SOUNDINGS NEVER PRESENTING ANY LAYERS NEAR ENOUGH TO
SATURATION TO WARRANT QPF...ESPECIALLY OVER THE LOWER DESERTS. THE
SET-UP IS STILL THERE FOR AFTERNOON AND EVENING HIGH-BASED
DEVELOPMENT OVER THE HIGHER TERRAIN TO THE EAST OF PHOENIX AND ACROSS
EASTERN ARIZONA...WITH STRONG GUSTY WINDS AND EVEN SOME LIGHTNING
STRIKES POSSIBLE BOTH FRIDAY AND SATURDAY. DAYTIME TEMPERATURES WILL
BEGIN TO WARM ACROSS SOUTHEAST CALIFORNIA FOR FRIDAY AND THEN WARMING
WILL EXPAND INTO THE ARIZONA BY THE WEEKEND WITH WIDESPREAD 90S...AND
EVEN SOME LOW 100S...POSSIBLE BY SUNDAY AS THE LOW EXITS INTO NEW
MEXICO.
THE UPPER LOW WILL EVENTUALLY MOVE BACK INTO THE MEAN STORM FLOW AND
CLEAR OUT OF THE SOUTHWEST STATES BY LATE MONDAY...LEAVING SUBTLE
RIDGE HEIGHTS OVERHEAD. UPPER LEVEL HEIGHTS QUICKLY BUILD BACK INTO
THE UPPER 580DM RANGE...WARMING TEMPERATURES BACK TO NORMAL AND THEN
ABOVE NORMAL READINGS BY EARLY NEXT WEEK. RIDGE HEIGHTS LOOK TO PEAK
BY TUESDAY/WEDNESDAY AS THE RIDGE AXIS MOVES INTO NEW MEXICO...WHILE
LONGWAVE TROUGHING DEVELOPS OFF THE WEST COAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...
ISOLATED CONVECTION IS EXPECTED TO DEVELOP THIS AFTERNOON WELL EAST
OF THE PHOENIX TERMINALS ACROSS EASTERN AZ. ACROSS THE PHOENIX
AREA...AFTERNOON BREEZINESS WILL AGAIN BE PREVALENT WITH OCCASIONAL
GUSTS AS HIGH AS 20 KT. A RETURN TO LIGHTER DOWNSLOPE EASTERLY FLOW
IS EXPECTED BETWEEN 06Z AND 08Z FRIDAY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
ISOLATED THUNDERSTORMS ARE LIKELY ACROSS SOUTHEASTERN CA THIS
AFTERNOON AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. STORMS WILL
GENERALLY REMAIN CONFINED TO THE HIGHER TERRAIN EAST OF SAN DIEGO
AND TOWARDS JOSHUA TREE NATIONAL PARK. HOWEVER...THERE IS A REMOTE
POSSIBILITY THAT AN ISOLATED CELL WILL AFFECT KIPL/KBLH WITH BRIEF
GUSTY WINDS. OTHERWISE...WINDS WILL PREDOMINATELY REMAIN OUT OF THE
SOUTH AND WEST...WITH GUSTS UP TO 20 KT LATE THIS AFTERNOON AND THIS
EVENING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
A LOW PRESSURE SYSTEM WILL CONTINUE MOVING SLOWLY EASTWARD THROUGH
AZ THIS WEEKEND. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE ACROSS NORTHEASTERN AZ THROUGH SUNDAY...THOUGH RAIN
CHANCES WILL BE CONSIDERABLY LESS ACROSS THE LOWER DESERTS. ISOLATED
DRY THUNDERSTORMS WILL ALSO REMAIN A THREAT AS WELL...PARTICULARLY
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX. WINDS WILL
GENERALLY REMAIN LIGHT...EXCEPT IN THE VICINITY OF THUNDERSTORMS.
AFTER SOMEWHAT COOLER CONDITIONS SATURDAY...A WARMING AND DRYING
TREND IS EXPECTED WITH ABOVE AVERAGE TEMPERATURES LIKELY BY MONDAY
AND CONTINUING THROUGH MIDWEEK.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...NOLTE
AVIATION....HIRSCH
FIRE WEATHER...HIRSCH
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
850 PM PDT FRI MAY 23 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE WILL BUILD OVER THE AREA THROUGH
THE HOLIDAY WEEKEND. WARMER TEMPERATURES CAN BE EXPECTED INLAND BUT NIGHT
AND MORNING LOW CLOUDS WITH PATCHY FOG CAN BE EXPECTED ALONG THE
COAST FOR THE NEXT SEVERAL NIGHTS. TEMPERATURES WILL COOL TO NEAR
NORMAL EARLY NEXT WEEK.
&&
.DISCUSSION...AS OF 8:50 PM PDT FRIDAY...HIGH PRESSURE CONTINUES
TO BUILD OVER THE EASTERN PACIFIC AS AN UPPER LOW SPINNING OVER
SOUTHERN CALIFORNIA SHOOTS EASTWARD. ABOVE NORMAL TEMPERATURES
ARE EXPECTED THROUGH THE HOLIDAY WEEKEND AS HIGH PRESSURE BUILDS
AT THE SURFACE AND ALOFT. 850 MB TEMPS ARE FORECAST TO GRADUALLY
INCREASE THROUGH THE WEEKEND...PEAKING ON SUNDAY AROUND 20 DEGREES
C. MEANWHILE 500 MB HEIGHTS WILL ALSO INCREASE WITH HEIGHTS ALSO
PEAKING ON SUNDAY AT AROUND 585 DAM. TEMPERATURES OVER THE WEEKEND
ARE FORECAST TO REACH INTO THE 60S AND 70S ALONG THE COAST AND
INTO THE 80S TO MID 90S INLAND. THE WARMEST INLAND LOCATIONS MAY
TOP OUT IN THE UPPER 90S ON SUNDAY.
CURRENT SATELLITE IMAGERY IS MAKING IT DIFFICULT TO SEE WHAT IS
HAPPENING AT THE SURFACE. HOWEVER BEFORE THE UPPER CLOUDS MOVED IN
AND HAMPERED OUR VIEW WE SAW SIGNIFICANT EROSION OF THE STRATUS
DECK ALONG THE COAST. THE LATEST RUN OF THE HRRR MODEL APPEARS TO
HAVE THE BEST HANDLE ON THE CURRENT SITUATION WHICH SHOWS STRATUS
RAPIDLY ERODING FROM THE MONTEREY COUNTY COAST WITH PATCHY LOW
CLOUDS REMAINING ONLY IN THE MONTEREY BAY. THE HRRR FORECAST
STRATUS TO RETURN TO THE NORTH COAST LATE TONIGHT...SPREADING
SOUTH THROUGH THE REMAINDER OF THE MORNING. THE FORECAST HAS BEEN
UPDATED TO REFLECT THIS CHANGE. CONFIDENCE IS LOW WITH RESPECT TO
STRATUS INTRUSION OVER THE NORTH BAY. WITH THE LATE ONSET OF THE
STRATUS ALONG THE COAST AND THE COMPRESSION OF THE MARINE LAYER
DUE TO BUILDING HIGH PRESSURE WE ANTICIPATE LESS INLAND STRATUS
INTRUSION THAN PREVIOUS NIGHTS.
FROM PREVIOUS DISCUSSION...
NORTHERLY PRESSURE GRADIENT RAMPS UP ON MONDAY AS HIGH PRESSURE
WEAKENS AND A TROUGH APPROACHES FROM THE NORTHWEST. THE INCREASED
GRADIENT/FLOW MAY BE STRONG ENOUGH TO DISRUPT THE MARINE LAYER AND
KEEP CLOUDS MAINLY OVER THE COASTAL WATERS. EITHER WAY...MEMORIAL
DAY IS SHAPING UP TO BE PLEASANT WITH NEAR NORMAL TEMPS ALONG THE
COAST AND SLIGHTLY ABOVE NORMAL TEMPS INLAND. IN OTHER
WORDS...JUST A TAD COOLER THAN SUNDAY.
LONG TERM(TUESDAY-FRIDAY)...
MUCH OF THE PATTERN FOR THE LONG TERM WILL BE A BROAD UPPER LEVEL
TROUGH OVER THE WEST COAST. THE TROUGH WILL KEEP THE MARINE LAYER
MIXED OUT. MORE SUNSHINE WILL BE SEEN...BUT THE TROUGH AND COOLER
AIRMASS WILL BRING TEMPERATURES CLOSER TO NORMAL.
&&
.AVIATION...AS OF 4:25 PM PDT FRIDAY...DIFFICULT LOW CLOUD
FORECAST FOR THE OVERNIGHT HOURS AS SIGNIFICANT CHANGES BEGIN WITH
THE UPPER LEVEL WEATHER PATTERN. AN UPPER LOW WILL CONTINUE TO
SHIFT SLOWLY EAST OUT OF SOUTHERN CA...WITH HIGH PRESSURE
BEGINNING TO BUILD OVER THE AREA. THE FORECAST MODELS INDICATE
THAT THE MARINE LAYER WILL BEGIN TO COMPRESS...FROM ITS CURRENT
1800 FOOT DEPTH. REGARDLESS...MODELS INDICATE A BIT LESS ON THE
STRATUS COVERAGE COMPARED TO LAST NIGHT. FORECASTER CONFIDENCE LOW
TO MEDIUM.
VICINITY OF KSFO...MODERATE ONSHORE WINDS WILL CONTINUE THROUGH
THE EVENING HOURS. MVFR TO IFR CIGS JUST AFTER MIDNIGHT...WITH
CLEARING AROUND 17Z SATURDAY. LOW CONFIDENCE. ONSHORE WINDS ARE
FORECAST TO BE A BIT STRONGER SATURDAY AFTERNOON COMPARED TO THIS
AFTERNOON...WITH WIND GUSTS TO 30 KT NOT OUT OF THE QUESTION.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WILL BECOME IFR BETWEEN 04
AND 06Z. MODERATE CONFIDENCE. THE FORECAST MODELS DO INDICATE THAT
KMRY MAY SEE PATCHY REDUCED VISIBILITIES FOR A FEW HOURS EARLY
SATURDAY MORNING...HOWEVER CONFIDENCE IS LOW AND IT WAS NOT ADDED
TO THE FORECAST.
&&
.MARINE...AS OF 8:10 PM PDT FRIDAY...NORTHERLY WINDS WILL INCREASE
THROUGH THE WEEKEND THROUGH MOST OF NEXT WEEK AS SURFACE HIGH
PRESSURE STRENGTHENS OVER THE EASTERN PACIFIC. THESE WINDS WILL
GENERATE STEEP FRESH SWELLS WHICH WILL BE PRESENT OVER THE WATERS
THROUGH AT LEAST FRIDAY OF NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT ARENA TO PT REYES 10-60 NM
SCA...PT REYES TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PINOS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: CW
AVIATION/MARINE: RILEY
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SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
455 PM PDT FRI MAY 23 2014
UPDATED AVIATION SECTION
.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY BUILD OVER SOUTHWEST CALIFORNIA THROUGH
THE WEEKEND. THIS WILL BRING A WARMING TREND TO THE AREA...ALTHOUGH
NIGHT AND MORNING STRATUS WILL CONTINUE TO IMPACT COASTAL AREAS. FOR
EARLY NEXT WEEK...A TROUGH WILL DEVELOP ALONG THE WEST COAST
BRINGING COOLER CONDITIONS AND A CONTINUATION OF THE COASTAL STRATUS
AND FOG.
&&
.SHORT TERM (TODAY-MON)...STARTING TO GET A FEW BUILDUPS THIS
AFTERNOON NEAR THE LA/SBD COUNTY LINE BUT OBVIOUSLY MUCH QUIETER SO
FAR THAN YESTERDAY. STILL LOOKING AT A SMALL CHANCE OF A STORM
DEVELOPING LATER THIS AFTERNOON OVER THE ERN SAN GABRIELS AS SOME
MOISTURE WRAPS AROUND THE BACK SIDE OF THE UPPER LOW OVER THE
COLORADO RIVER, THOUGH THE HRRR MODEL NOW INDICATES NO SIGNIFICANT
DEVELOPMENT.
HIGH PRESSURE NUDGING INTO THE AREA FROM THE WEST WILL BRING WARMER
AIR ALOFT, SHRINKING THE MARINE LYR BY A GOOD 1000 FT. WEB CAMS
ALONG THE CENTRAL COAST ALREADY SHOWING LOWER CLOUD BASES OFFSHORE.
THIS COULD LEAD TO SOME DENSE FOG FOR PORTIONS OF THE CENTRAL COAST
TONIGHT. INCREASING NORTHWEST FLOW WITH THE BUILDING HIGH WILL BRING
SOME GUSTY WINDS TO THE CENTRAL COAST AND SRN SBA COUNTY THIS
AFTERNOON AND EVENING BUT BELOW ADVISORY LEVELS FOR THE MOST PART.
LOW CLOUDS EXPECTED TO FILL IN ACROSS LA/VENTURA COUNTY WITH THE
STRENGTHENING INVERSION, THOUGH WITH LOWER BASES. WILL TAKE A LITTLE
LONGER TO FILL IN ACROSS SRN SBA COUNTY DUE TO THE WEAK SUNDOWNERS
THERE THIS EVENING.
REMAINDER OF THE FORECAST REMAINS LARGELY UNCHANGED FROM THE LAST
COUPLE DAYS. THE WARMING TREND WILL CONTINUE THROUGH THE WEEKEND,
PEAKING EITHER MONDAY OR TUESDAY. MARINE LYR WILL SHRINK EACH DAY
WITH LESS INLAND PUSH. WILL LIKELY REACH THE VALLEYS THROUGH SUNDAY
BUT PROBABLY NOT MONDAY. STRONG ONSHORE FLOW WILL KEEP CLOUDS
HUGGING THE COAST THROUGH THE AFTERNOON, KEEPING SOME BEACHES
OVERCAST WELL INTO THE AFTERNOON. WHILE VALLEYS WILL WARM UP INTO
THE 80S SUNDAY AND POSSIBLY NEAR 90 MONDAY, COASTAL AREAS WILL
REMAIN MOSTLY IN THE 60S TO LOWER 70S. INTERIOR SLO COUNTY WILL BE A
DAY AHEAD WITH THE WARMING BEING CLOSER TO THE RIDGE SO PLACES LIKE
PASO ROBLES WILL BE THE 90S BY SUNDAY.
.LONG TERM (TUE-FRI)...ECMWF CONTINUES TO BE A LITTLE FASTER WITH
THE TROF NEXT WEEK, MEANING A SLIGHT DIFFERENCE OF OPINION WITH
REGARD TO THE START OF THE COOLING TREND. OTHERWISE REALLY NO
SIGNIFICANT DIFFERENCES IN THE PATTERN. BOTH MODELS INDICATE ABOUT
5-10 DEGREES OF COOLING FOR INLAND AREAS BY THU AND FRI WITH THE
MARINE LYR PUSHING BACK INTO THE VALLEYS.
&&
.AVIATION...23/2355Z.
EXPECT WDSPRD CIGS IN ALL COASTAL AND VALLEY AREAS LATER
TONIGHT...WITH CONDS MOSTLY MVFR ACROSS L.A. AND VTU COUNTIES...AND
IFR TO LIFR ACROSS SLO AND SBA COUNTIES. EXPECT SLOW CLEARING NEAR
THE COAST SAT AFTERNOON...WITH CLOUDS POSSIBLY LINGERING ALL DAY IN
SOME LOCATIONS. GUSTY WINDS WILL AFFECT THE ANTELOPE VALLEY SAT
AFTERNOON.
.KLAX...MODERATE CONFIDENCE IN 00Z TAF. THERE IS A 20 TO 30 PERCENT
CHANCE THAT THERE WILL BE NO CLEARING ON SAT.
.KBUR...MODERATE TO HIGH CONFIDENCE IN TAF. THERE IS A 20 PERCENT
CHANCE THAT CIGS WILL ARRIVE AS EARLY AS 08Z.
&&
.MARINE...23/100 PM.
THERE IS A CHANCE SMALL CRAFT ADVISORY CONDITIONS WILL DEVELOP IN
THE OUTER WATERS THIS AFTERNOON AND THEN PERSIST THROUGH TUESDAY.
THE ADVISORY CONDITIONS WILL LIKELY PUSH INTO THE INNER WATERS ALONG
THE SLO COAST SATURDAY. OTHERWISE A CATALINA EDDY WILL DEVELOP IN
THE LATE EVENING EACH NIGHT AND DISSIPATE BY EARLY AFTERNOON THROUGH
THE PERIOD. LOCALLY GENERATED SHORT PERIOD SEAS FROM THE NORTHWEST
AND SMALL LONG PERIOD SWELL FROM THE SOUTH WILL PERSIST.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...MW
AVIATION...DB
MARINE...30
SYNOPSIS...SMITH
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
145 PM PDT THU MAY 22 2014
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE
MOUNTAINS AND DESERTS THROUGH THIS EVENING...WITH ISOLATED SHOWERS
AND THUNDERSTORMS POSSIBLE WEST OF THE MOUNTAINS. ALTHOUGH DRIER
CONDITIONS WILL DEVELOP ON FRIDAY...AS THE TROUGH MOVES EAST...SOME
LINGERING INSTABILITY AND MOISTURE WILL CONTINUE THE THREAT OF
SHOWERS OVER THE MOUNTAINS AND DESERTS. DRY AND WARMER CONDITIONS
WILL THEN DEVELOP FOR THE HOLIDAY WEEKEND...WITH SOME COASTAL LOW
CLOUDS AND FOG POSSIBLE EACH NIGHT. A GRADUAL COOLING TREND WILL
THEN DEVELOP FOR THE MIDDLE AND LATTER PART OF THE WORK WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OVER SOUTHERN
CALIFORNIA THIS AFTERNOON. AS A RESULT...SCATTERED SHOWERS AND
THUNDERSTORMS ARE DEVELOPING OVER THE MOUNTAINS AND DESERTS.
CURRENTLY...AN URBAN AND SMALL STREAM FLOOD ADVISORY IS IN EFFECT
FOR A PORTION OF THE SAN DIEGO COUNTY DESERTS...EAST OF SHELTER
VALLEY. MEANWHILE...A THICK BLANKET OF LOW CLOUDS LINGERS WEST OF
THE MOUNTAINS. ALTHOUGH THERE ARE A FEW BREAKS IN THE
CLOUDS...MAINLY OVER THE INLAND EMPIRE...THERE ARE NOW ENOUGH HIGH
CLOUDS LIMITING THE SURFACE HEATING. THE HRRR AND LOCAL WRF ARE
STILL INDICATING THAT THE ELSINORE CONVERGENCE ZONE WILL GENERATE
SOME ACTIVITY LATE THIS AFTERNOON AND DURING THE EARLY EVENING
HOURS...SO HAVE KEPT A MENTION OF SHOWERS AND THUNDERSTORMS IN THE
FORECAST FOR THE INLAND VALLEYS. HOWEVER...CONFIDENCE IS LOW GIVEN
THE CURRENT SATELLITE TRENDS.
THIS UPPER LEVEL TROUGH WILL SLOWLY SHIFT EAST TONIGHT AND DURING
THE DAY ON FRIDAY. AS A RESULT...MOST AREAS WILL SEE DRIER AND
WARMER CONDITIONS DEVELOP. HOWEVER...THERE WILL BE ENOUGH LINGERING
INSTABILITY AND MOISTURE OVER THE MOUNTAINS AND DESERTS...THAT
ISOLATED SHOWERS AND THUNDERSTORMS COULD DEVELOP ONCE AGAIN. HIGH
PRESSURE THEN BUILD BACK ACROSS SOUTHERN CALIFORNIA FOR THE MEMORIAL
DAY WEEKEND...WITH EVEN WARMER AND DRIER CONDITIONS DEVELOPING. A
SHALLOW MARINE LAYER WILL REMAIN ALONG THE COAST THOUGH...WITH NIGHT
AND MORNING LOW CLOUDS AND FOG POSSIBLE. ANOTHER TROUGH WILL THEN
DIG ALONG THE WEST COAST BY THE MIDDLE PART OF THE WORK WEEK...WITH
COOLER CONDITIONS AND A MORE EXTENSIVE MARINE LAYER DEVELOPING ONCE
AGAIN.
&&
.AVIATION...
222000Z...COAST/VALLEYS...AREAS OF LOW CLOUDS WITH BKN-OVC CIGS
2500-4000 FT MSL LAYERED TO 15000 FT. HIGHER TERRAIN WILL BE
OBSCURED WITH AREAS OF FOG REDUCING VIS TO 3-5SM WHERE CLOUDS AND
TERRAIN INTERSECT. LOW CLOUDS BECOME WIDESPREAD AGAIN AFTER 03Z FRI
WITH OVC BASES 2000-3000 FT MSL AND TOPS NEAR 6000 FT
MSL...OBSCURING HIGHER TERRAIN. PARTIAL CLEARING TO THE COAST AFT
18Z FRI.
MTNS/DESERTS...ISOLATED-SCT SHOWERS AND TSTMS THROUGH 05Z FRI.
&&
.MARINE...
200 PM...ISOLATED SHOWERS POSSIBLE OVER THE COASTAL WATERS THIS
AFTERNOON. NO HAZARDOUS MARINE WEATHER IS EXPECTED FRIDAY THROUGH
SUNDAY.
&&
.FIRE WEATHER...
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE
MOUNTAINS AND DESERTS THROUGH THIS EVENING...WITH ISOLATED SHOWERS
AND THUNDERSTORMS POSSIBLE WEST OF THE MOUNTAINS...AS A COLD TROUGH
OF LOW PRESSURE REMAINS OVER SOUTHERN CALIFORNIA. BRIEF AND LOCALLY
HEAVY RAIN WILL CONTINUE TO BE POSSIBLE...WITH THESE THUNDERSTORMS.
ALTHOUGH WETTING RAINS MAY OCCUR...THERE IS STILL THE POSSIBILITY OF
LIGHTNING STRIKES STARTING FIRES OUTSIDE OF THE SHOWERS.
A FEW SHOWERS MAY DEVELOP OVER THE MOUNTAINS AND DESERTS AGAIN ON
FRIDAY AFTERNOON. DRY AND WARMER CONDITIONS WILL DEVELOP FOR THIS
HOLIDAY WEEKEND.
&&
.SKWYARN...
SKYWARN ACTIVATION IS REQUESTED FOR SAN BERNARDINO...RIVERSIDE...AND
SAN DIEGO COUNTIES.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC/FIRE WEATHER...PALMER
AVIATION/MARINE...PG
AREA FORECAST DISCUSSION
NWS PUEBLO CO
553 PM MDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 541 PM MDT FRI MAY 23 2014
LOADED LATEST OBSERVATIONS INTO SHORT TERM FORECAST GRIDS. NO
OTHER UPDATES TO FORECAST AT THIS TIME. LW
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 332 PM MDT FRI MAY 23 2014
CURRENTLY...CONVECTION RATHER SPARSE ACROSS SOUTHERN COLORADO SO FAR
THIS AFTERNOON...THOUGH AREA OF MORE VIGOROUS TSRA WASN`T TOO FAR
AWAY OVER NRN NM. AIR MASS OVER THE REGION REMAINS MODERATELY
UNSTABLE...AND EXPECT AN INCREASE IN STORMS MOST AREAS THROUGH THE
REMAINDER OF THE AFTERNOON...AS SEVERAL WEAK BOUNDARIES EVIDENT IN
KPUX RADAR DATA MAY CONVERGE ACROSS PUEBLO/EL PASO COUNTIES 21Z-
23Z...WHICH COULD FORCE SOME NEW CONVECTION. MESOSCALE
MODELS...INCLUDING THE LATEST HRRR SUPPORT THE IDEA OF INCREASING
TSRA OVER THE PLAINS THROUGH EARLY EVENING AS WELL. CONVECTION WILL
GRADUALLY WANE BY MIDNIGHT...THOUGH WITH MODELS HINTING AT OVERNIGHT
MCS ACROSS NRN NM...WILL KEEP SOME LOW POPS GOING DURING THE
NIGHT...MAINLY ACROSS SOUTHERN ZONES.
MESOSCALE DETAILS WILL LIKELY DRIVE CONVECTION ON SATURDAY...AS SOME
SORT OF WEAKENING MCS WILL BE MOVING OUT OF NERN NM/TX PANH INTO THE
SOUTHEAST PLAINS DURING THE MORNING. DEPENDING ON STRENGTH OF
MCS...MUCH OF AREA ALONG AND EAST OF THE MOUNTAINS MAY SEE SOME
FAIRLY HEALTHY SUBSIDENCE ON THE BACK SIDE OF THE SYSTEM...WHICH
WOULD LIMIT TSRA CHANCES. STILL...WITH MODERATE INSTABILITY COVERING
MOST OF THE AREA...TOUGH TO RULE OUT STORMS JUST ABOUT ANYWHERE
DURING THE AFTERNOON. BEST PRECIP COVERAGE MAY END UP OVER THE
SOUTHWEST MOUNTAINS...WHERE STRONG DYNAMIC LIFT FROM THE UPPER LOW
COMES INTO PLAY DURING THE LATE AFTERNOON. SEVERE THREAT LOOKS LOW
ONCE AGAIN...AS DEEPER INSTABILITY AND STRONGER WIND SHEAR REMAIN TO
THE SOUTH OVER WRN TX. MAX TEMPS SHOULD STAY RELATIVELY
UNCHANGED...WITH READINGS REMAINING BELOW SEASONAL AVERAGES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 332 PM MDT FRI MAY 23 2014
SATURDAY NIGHT THROUGH TUESDAY...A VERY UNSETTLED PATTERN IN PLACE
OVER THE HOLIDAY WEEKEND...AND THE GFS...NAM AND EC MODELS ALL SEEM
TO AGREE ON THIS. THE UPPER LOW CURRENTLY OVER SOUTHWESTERN AZ IS
EXPECTED TO SLOWLY MEANDER ALONG THE CO/NM STATE LINE SAT NIGHT
THROUGH MON...BEFORE EXITING TO THE EAST ACROSS THE OK AND TX
PANHANDLES ON TUE. A COUPLE OF THINGS TO NOTE WITH THIS SYSTEM. THE
SLOW MOVEMENT AND THE EXPECTED PLACEMENT OF THE LOW MEANS THAT THERE
IS THE POTENTIAL FOR SOME HEAVY RAINFALL IN PLACES. MODELS ALSO
INDICATE A POSSIBLE DRY SLOT FOR SUNDAY ACROSS THE PLAINS. WHERE THE
HEAVY RAINFALL OCCURS...AND WHERE AND WHEN THE DRY SLOT WILL
HAPPEN...IS VERY DIFFICULT TO PREDICT AT THIS TIME.
THEREFORE...BLANKETED MOSTLY CLOUDY TO OVERCAST SKIES FOR THE
FORECAST AREA FOR MUCH OF THE WEEKEND...AND WENT WITH AT LEAST
ISOLATED POPS FOR MUCH OF THE AREA AT ALL TIMES. MODELS INDICATE THE
DRY SLOT WILL OCCUR SUNDAY OVER THE PLAINS...SO LESSENED SKY COVER
AND LOWERED POPS THERE DURING THAT TIME FRAME.
OTHERWISE...CONVECTION WILL OCCUR IN BANDS AND EXACT AMOUNTS AND
PLACEMENT ARE IMPOSSIBLE AT THIS TIME. AS FOR TEMPS...SHOULD BE
FAIRLY WARM WITH MAX TEMPS NEAR 80 F FOR THE PLAINS EACH
DAY...THOUGH ONGOING MAX TEMP FOR TUE WILL MOST LIKELY HAVE TO BE
COOLED. AREA BURN SCARS WILL NEED TO BE MONITORED CLOSELY EACH DAY
OVER THE HOLIDAY WEEKEND.
WEDNESDAY THROUGH FRIDAY...EXTENDED MODELS INDICATE THAT THE UPPER
LOW WILL HAVE FINALLY MOVED EAST OF THE AREA AND OUT OF COLORADO BY
TUE EVE...WITH RIDGING DEVELOPING ACROSS THE DESERT SW FOR THE
SECOND HALF OF THE WEEK. THE GFS PAINTS A VERY WET PICTURE...WHILE
THE EC IS LEANING TOWARDS A MORE PROBABLE SOLUTION OF DIURNAL MT
CONVECTION AND PREDOMINANTLY DRY ELSEWHERE. THEREFORE...AMENDED THE
EXTENDED PROCEDURE POP GRIDS TO SHOW ISOLATED TO LOW END SCATTERED
POPS OVER THE MTS AND ADJACENT PLAINS EACH AFTN AND EVE...THEN DRY
WITH CLEARING SKIES OVERNIGHT. SEASONABLE TEMPS ARE FORECAST...WITH
MAX TEMPS IN THE 80S FOR THE PLAINS AND 70S FOR THE HIGH VALLEYS.
MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 332 PM MDT FRI MAY 23 2014
WILL CARRY A VCTS MENTION ALL 3 TAF SITES FROM 21Z UNTIL 02Z-
04Z...AND UPDATE TAFS AS STORMS GET CLOSER TO THE TERMINALS. MAY SEE
SOME INCREASING TSRA ACTIVITY KCOS AND KPUB 22Z-23Z AS SEVERAL
OUTFLOW BOUNDARIES COLLIDE IN THE GENERAL AREA. SOME OF THE STRONGER
STORMS MAY PRODUCE BRIEF MVFR CIGS/VIS...ALONG WITH SOME SMALL HAIL
AND GUSTY WINDS. EXPECT ACTIVITY TO GRADUALLY DIMINISH TO A FEW
SHOWERS LATE EVENING AND OVERNIGHT. EARLY MORNING STRATUS HAS BEEN
RATHER PATCHY THE PAST COUPLE DAYS...SO WILL KEEP MENTION OUT OF
TAFS FOR NOW...THOUGH THERE WILL STILL BE A THREAT FOR SOME MVFR
CIGS AFTER SUNRISE SATURDAY...ESPECIALLY EAST OF I-25. LITTLE CHANGE
IN THE PATTERN ON SATURDAY...WITH SCATTERED CONVECTION MOST AREAS
ONCE AGAIN.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...LW
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1001 AM MDT THU MAY 22 2014
.UPDATE...
ISSUED AT 1001 AM MDT THU MAY 22 2014
MOSTLY SUNNY SKIES THIS MORNING AND SLIGHTLY WARMER TEMPERATURES
ALOFT ALLOW TEMPERATURES TO BE WARMER TODAY. LOOKING LIKE HIGHS
WILL BE IN THE LOWER TO MID 70S FOR MOST OF THE AREA TODAY. THESE
TEMPERATURES COMBINED WITH DEW POINTS IN THE UPPER 40S TO LOWER
50S WILL YIELD CAPES OF 1000-2000 J/KG. PLENTY OF INSTABILITY FOR
SEVERE STORMS AGAIN. MID LEVEL WINDS HAVE DECREASED...THUS SHEAR
WILL BE LESS TODAY. THIS WILL REDUCE THE THREAT FOR LONG LIVED
SUPERCELLS. STILL A THREAT FOR LARGE HAIL AND DAMAGING WINDS. IF A
TORNADO WHERE TO FORM...BEST CHANCE WILL BE ALONG A BOUNDARY THAT
IS FORECASTED TO SET UP JUST SOUTH OF DENVER...OR ALONG ANY
OUTFLOW BOUNDARY THAT INTERACTS WITH AN UPDRAFT.
LATEST HRRR MODEL SHOWS THE GREATEST STORM COVERAGE ALONG AND
SOUTH OF INTERSTATE 70. INCREASED POPS FOR THIS AREA THIS
AFTERNOON AND EARLY EVENING. BECAUSE OF THE WEAKER WINDS
ALOFT...STORMS WILL BE MOVING SLOWER TODAY. THIS WILL INCREASE THE
THREAT FOR HEAVY RAIN AND LOCALIZED FLOODING.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 305 AM MDT THU MAY 22 2014
THE UPPER LEVEL LOW WILL REMAIN OVER THE SWRN US THROUGH TONIGHT AS
A SERIES OF WEAK DISTURBANCES MOVE NNE AHEAD OF THE SYSTEM ACROSS
COLORADO. APPEARS ONE SUCH FEATURE MAY TRACK ACROSS THE AREA THIS
AFTN WHILE ANOTHER MOVES INTO THE AREA LATE TONIGHT. AT THE SFC
WILL PROBABLY SEE A SFC LOW DVLP IN THE SRN FOOTHILLS WITH A
CONVERGENCE ZONE SETTING UP OVER THE PALMER DIVIDE WITH ELY LOW LVL
FLOW FM DENVER NORTH TO THE WY BORDER. SFC BASED CAPES BY AFTN WILL
RANGE FM 1500-2000 J/KG FM THE FOOTHILLS ACROSS THE PLAINS EXCEPT
OVER THE NERN CORNER WHERE CAPES MAY STAY BLO 1000 J/KG. OVERALL
MID LVL FLOW IS FCST TO BE WEAKER TODAY SO SHEAR PROFILE WILL NOT BE
AS STRONG. HOWEVER STILL EXPECT A FEW SVR STORMS THIS AFTN INTO THE
EARLY EVENING HOURS WITH A FEW BRIEF TORNADOS POSSIBLE ALONG THE
CONVERGENCE ZN. AT THIS TIME BEST POTENTIAL FOR SVR WEATHER LOOKS
TO BE ALONG AND SOUTH OF A LINE FROM DENVER INTO SRN WASHINGTON
COUNTY UNLESS CONVERGENCE ZN SHIFTS FURTHER NORTH.
PRECIPITABLE WATER VALUES HAVE BEEN SLOWLY INCREASING AND COULD BE
NEAR AN INCH BY LATER THIS AFTN AND WITH SLOWER STORM MOTIONS THERE
WILL BE THE POTENTIAL FOR HEAVIER RAINFALL. AT THIS POINT IT
APPEARS MOST OF THE HEAVIER RAINFALL WILL BE AT LOWER ELEVATIONS
ALTHOUGH THERE COULD BE SOME HEAVY RAIN IN THE FOOTHILLS DUE TO THE
ELY LOW LVL FLOW. AS FOR TEMPS WILL KEEP READINGS MOSTLY IN THE
LOWER TO MID 70S OVER NERN CO ALTHOUGH THE RAP SUGGEST READINGS OVER
THE NERN CORNER MAY STAY IN THE 60S DUE TO EXTENSIVE LOW CLOUDS.
FOR TONIGHT STORMS OVER THE PLAINS WILL LIKELY EVOLVE INTO AN MCS
AND MOVE EASTWARD INTO THE CNTRL HIGH PLAINS THIS WILL HAVE HIGHER
POPS THIS EVENING FROM SOUTH OF AKRON TO LIMON. LATER TONIGHT
ANOTHER DISTURBANCE MAY MOVE ACROSS THE AREA WHICH COULD INCREASE
THE CHC FOR SHOWERS AND A FEW TSTMS AFTER MIDNIGHT. FOR NOW WILL
JUST KEEP POPS IN THE CHC CATEGORY DUE TO UNCERTAINTY WITH TIMING OF
THIS FEATURE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 305 AM MDT THU MAY 22 2014
SOUTHERLY FLOW ALOFT WILL CONTINUE FRIDAY WITH LOWER LEVEL
SOUTHEASTERLY UPSLOPE FLOW. SHOWERS ARE EXPECTED TO BE ONGOING IN
THE MORNING WITH A FEW THUNDERSTORMS POSSIBLE. OVERALL...CAPES
WILL BE LOWER AS UPPER LEVELS WARM SLIGHTLY AND LOWER LEVELS
REMAIN SLIGHTLY COOLER DURING THE DAY AS CLOUD-COVER WILL PREVAIL
THROUGH THE DAY. CAPE VALUES OF 250-700 J/KG ARE EXPECTED OVER THE
DAY...WITH THE HIGHEST VALUES OVER THE EASTERN PLAINS. SLOW STORM
MOTION EXPECTED THAT DAY SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE...ESPECIALLY WHERE THE LOW LEVEL UPSLOPE FLOW PUSHES
AGAINST THE FOOTHILLS AND HIGHER TERRAIN. GIVEN THE LOWER CAPES
NEAR THE FOOTHILLS THOUGH...STORMS ARE NOT EXPECTED TO GET THAT
STRONG. WILL STILL BE ON ALERT WITH INCREASED MOISTURE SURGE FROM
THE SOUTH TO WATCH FOR POTENTIAL HEAVY RAIN. COULD SEE SOME SMALL
HAIL ACROSS THE PLAINS.
ACTIVITY WILL LIKELY CONTINUE...ALTHOUGH AT A DECREASED RATE
OVERNIGHT. THE UPPER LOW WILL LIFT NORTHEAST TOWARD THE STATE
SATURDAY WITH SLIGHTLY INCREASED FLOW ALOFT. EXPECT CONTINUED
SHOWERS AND THUNDERSTORMS ACROSS THE AREA WITH LOCALLY HEAVY
RAINFALL AND SMALL HAIL THE MAIN CONCERNS AGAIN AS CAPES REMAIN IN
THE 250-500 J/KG. AN DRIER AREA SHOWN IN ALL MODELS WILL MOVE UP
INTO EASTERN COLORADO SATURDAY NIGHT TO SUBSTANTIALLY DRY
CONDITIONS AND POSSIBLE STOP ALL SHOWER ACTIVITY OVERNIGHT...THE
FIRST TIME IN SEVERAL NIGHTS.
THE UPPER LOW IS PROGGED TO MOVE EAST OVER SOUTHEASTERN COLORADO.
IF THE PREVIOUSLY MENTIONED DRY AREA IS STILL OVER THE AREA...MAY
NOT SEE MUCH ACTIVITY OVER THE PLAINS WHILE THE MOUNTAINS WILL
CONTINUE TO SEE SCATTERED SHOWERS AND THUNDERSTORMS. A COUPLE OF
THE MODELS ARE SHOWING A HEALTHY BAND OF PRECIPITATION FORM ON THE
BACKSIDE OF THE LOW OVER WESTERN COLORADO AND THE MOUNTAINS...WILL
CONTINUE FOLLOWING THIS SOLUTION. THE UPPER LOW WILL THEN MOVE
EAST INTO THE TX/OK PANHANDLES TO ALLOW FOR UPPER RIDGING MONDAY
AND TUESDAY...BRINGING WARMER AND DRIER CONDITIONS. COULD STILL
SEE ISOLATED TO SCATTERED SHOWERS MONDAY WHILE THE SYSTEM MOVES
FURTHER AWAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1001 AM MDT THU MAY 22 2014
STILL ON TRACK TO SEE ANOTHER ROUND OF THUNDERSTORMS BETWEEN 2000Z
AND 2400Z. STORMS MAY BRING SOME HAIL TO ONE INCH IN DIAMETER
ALONG WITH HEAVY RAINFALL. EXPECT MOST OF THE ACTIVITY WILL MOVE
EAST OF DIA BY 0000Z WITH IMPROVING CONDITIONS. WINDS ARE EXPECTED
TO BECOME EAST LATE THIS MORNING. ONCE STORMS FORM...OUTFLOW
BOUNDARIES WILL MOVE ACROSS CAUSING VARIABLE WIND DIRECTIONS. BY
THIS EVENING...WINDS WILL TURN MORE SOUTHEAST. ANOTHER
DISTURBANCE MAY MOVE ACROSS LATE TONIGHT BRINGING A CHANCE OF
SHOWERS AND POSSIBLY A THUNDERSTORM. MORE LOW CLOUDS AND POSSIBLY
FOG ARE EXPECTED FRIDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 305 AM MDT THU MAY 22 2014
STORMS THIS AFTERNOON WILL BE SLOWER MOVING SO THERE WILL BE A
HIGHER POTENTIAL FOR HEAVY RAINFALL IN SOME AREAS WITH UP TO 2
INCHES IN 45 MINUTES OR LESS. THE HEAVIEST RAINFALL WILL STAY OVER
THE PLAINS ALTHOUGH THERE COULD BE SOME SLOW MOVING TSTMS IN THE
FOOTHILLS WHICH COULD PRODUCE UP TO AN INCH OF RAIN IN 30 MINUTES IN
A FEW LOCATIONS.
STILL KEEPING A WATCHFUL EYE ON FRIDAY AND SATURDAY FOR HEAVY
RAINFALL FROM STORMS AS THE MOISTURE SURGE MOVES INTO THE STATE
FROM THE SOUTH. INSTABILITY WILL BE WEAKER BUT STILL EXPECTING
SLOWER MOVING STORMS. UPSLOPE FLOW SEEMS TO BE SLIGHTLY WEAKENING
AND A SURFACE TROUGH MAY ALTER THE UPSLOPE FLOW TO LITTLE OR NONE
AT TIMES.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MEIER
SHORT TERM...RPK
LONG TERM...KRIEDERMAN
AVIATION...MEIER
HYDROLOGY...KRIEDERMAN/RPK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
334 AM MDT THU MAY 22 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 305 AM MDT THU MAY 22 2014
THE UPPER LEVEL LOW WILL REMAIN OVER THE SWRN US THROUGH TONIGHT AS
A SERIES OF WEAK DISTURBANCES MOVE NNE AHEAD OF THE SYSTEM ACROSS
COLORADO. APPEARS ONE SUCH FEATURE MAY TRACK ACROSS THE AREA THIS
AFTN WHILE ANOTHER MOVES INTO THE AREA LATE TONIGHT. AT THE SFC
WILL PROBABLY SEE A SFC LOW DVLP IN THE SRN FOOTHILLS WITH A
CONVERGENCE ZONE SETTING UP OVER THE PALMER DIVIDE WITH ELY LOW LVL
FLOW FM DENVER NORTH TO THE WY BORDER. SFC BASED CAPES BY AFTN WILL
RANGE FM 1500-2000 J/KG FM THE FOOTHILLS ACROSS THE PLAINS EXCEPT
OVER THE NERN CORNER WHERE CAPES MAY STAY BLO 1000 J/KG. OVERALL
MID LVL FLOW IS FCST TO BE WEAKER TODAY SO SHEAR PROFILE WILL NOT BE
AS STRONG. HOWEVER STILL EXPECT A FEW SVR STORMS THIS AFTN INTO THE
EARLY EVENING HOURS WITH A FEW BRIEF TORNADES POSSIBLE ALONG THE
CONVERGENCE ZN. AT THIS TIME BEST POTENTIAL FOR SVR WEATHER LOOKS
TO BE ALONG AND SOUTH OF A LINE FROM DENVER INTO SRN WASHINGTON
COUNTY UNLESS CONVERGENCE ZN SHIFTS FURTHER NORTH.
PRECIPITABLE WATER VALUES HAVE BEEN SLOWLY INCREASING AND COULD BE
NEAR AN INCH BY LATER THIS AFTN AND WITH SLOWER STORM MOTIONS THERE
WILL BE THE POTENTIAL FOR HEAVIER RAINFALL. AT THIS POINT IT
APPEARS MOST OF THE HEAVIER RAINFALL WILL BE AT LOWER ELEVATIONS
ALTHOUGH THERE COULD BE SOME HEAVY RAIN IN THE FOOTHILLS DUE TO THE
ELY LOW LVL FLOW. AS FOR TEMPS WILL KEEP READINGS MOSTLY IN THE
LOWER TO MID 70S OVER NERN CO ALTHOUGH THE RAP SUGGEST READINGS OVER
THE NERN CORNER MAY STAY IN THE 60S DUE TO EXTENSIVE LOW CLOUDS.
FOR TONIGHT STORMS OVER THE PLAINS WILL LIKELY EVOLVE INTO AN MCS
AND MOVE EASTWARD INTO THE CNTRL HIGH PLAINS THIS WILL HAVE HIGHER
POPS THIS EVENING FROM SOUTH OF AKRON TO LIMON. LATER TONIGHT
ANOTHER DISTURBANCE MAY MOVE ACROSS THE AREA WHICH COULD INCREASE
THE CHC FOR SHOWERS AND A FEW TSTMS AFTER MIDNIGHT. FOR NOW WILL
JUST KEEP POPS IN THE CHC CATEGORY DUE TO UNCERTAINTY WITH TIMING OF
THIS FEATURE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 305 AM MDT THU MAY 22 2014
SOUTHERLY FLOW ALOFT WILL CONTINUE FRIDAY WITH LOWER LEVEL
SOUTHEASTERLY UPSLOPE FLOW. SHOWERS ARE EXPECTED TO BE ONGOING IN
THE MORNING WITH A FEW THUNDERSTORMS POSSIBLE. OVERALL...CAPES
WILL BE LOWER AS UPPER LEVELS WARM SLIGHTLY AND LOWER LEVELS
REMAIN SLIGHTLY COOLER DURING THE DAY AS CLOUD-COVER WILL PREVAIL
THROUGH THE DAY. CAPE VALUES OF 250-700 J/KG ARE EXPECTED OVER THE
DAY...WITH THE HIGHEST VALUES OVER THE EASTERN PLAINS. SLOW STORM
MOTION EXPECTED THAT DAY SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE...ESPECIALLY WHERE THE LOW LEVEL UPSLOPE FLOW PUSHES
AGAINST THE FOOTHILLS AND HIGHER TERRAIN. GIVEN THE LOWER CAPES
NEAR THE FOOTHILLS THOUGH...STORMS ARE NOT EXPECTED TO GET THAT
STRONG. WILL STILL BE ON ALERT WITH INCREASED MOISTURE SURGE FROM
THE SOUTH TO WATCH FOR POTENTIAL HEAVY RAIN. COULD SEE SOME SMALL
HAIL ACROSS THE PLAINS.
ACTIVITY WILL LIKELY CONTINUE...ALTHOUGH AT A DECREASED RATE
OVERNIGHT. THE UPPER LOW WILL LIFT NORTHEAST TOWARD THE STATE
SATURDAY WITH SLIGHTLY INCREASED FLOW ALOFT. EXPECT CONTINUED
SHOWERS AND THUNDERSTORMS ACROSS THE AREA WITH LOCALLY HEAVY
RAINFALL AND SMALL HAIL THE MAIN CONCERNS AGAIN AS CAPES REMAIN IN
THE 250-500 J/KG. AN DRIER AREA SHOWN IN ALL MODELS WILL MOVE UP
INTO EASTERN COLORADO SATURDAY NIGHT TO SUBSTANTIALLY DRY
CONDITIONS AND POSSIBLE STOP ALL SHOWER ACTIVITY OVERNIGHT...THE
FIRST TIME IN SEVERAL NIGHTS.
THE UPPER LOW IS PROGGED TO MOVE EAST OVER SOUTHEASTERN COLORADO.
IF THE PREVIOUSLY MENTIONED DRY AREA IS STILL OVER THE AREA...MAY
NOT SEE MUCH ACTIVITY OVER THE PLAINS WHILE THE MOUNTAINS WILL
CONTINUE TO SEE SCATTERED SHOWERS AND THUNDERSTORMS. A COUPLE OF
THE MODELS ARE SHOWING A HEALTHY BAND OF PRECIPITATION FORM ON THE
BACKSIDE OF THE LOW OVER WESTERN COLORADO AND THE MOUNTAINS...WILL
CONTINUE FOLLOWING THIS SOLUTION. THE UPPER LOW WILL THEN MOVE
EAST INTO THE TX/OK PANHANDLES TO ALLOW FOR UPPER RIDGING MONDAY
AND TUESDAY...BRINGING WARMER AND DRIER CONDITIONS. COULD STILL
SEE ISOLATED TO SCATTERED SHOWERS MONDAY WHILE THE SYSTEM MOVES
FURTHER AWAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 305 AM MDT THU MAY 22 2014
SATELLITE SHOWS STRATUS NEAR DIA WITH A HOLE OVER THE AIRPORT SO
FAR. HOWEVER WOULD EXPECT STRATUS TO DVLP IN THE NEXT FEW HOURS.
MEANWHILE THE HRRR AND RAP HAVE VASTLY DIFFERENT SOLUTION WITH
REGARDS TO FOG DEVELOPMENT. THE HRRR HAS NO FOG WHILE THE RAP HAS
DENSE FOG AFFECTING DIA BETWEEN 12Z AND 14Z. AT THIS TIME NOT SURE
WHICH MODEL WILL BE RIGHT SO WILL JUST MENTION A TEMPO GROUP FOR 3-5
MILE VISIBILITIES FOR NOW.
FOR THIS AFTN WILL SEE ANOTHER ROUND OF TSTMS BETWEEN 2 PM AND 5 PM.
STORMS MAY BRING SOME HAIL TO ONE INCH IN DIAMETER ALONG WITH HEAVY
RAINFALL. EXPECT MOST OF THE ACTIVITY WILL MOVE EAST OF DIA BY 5 PM
WITH IMPROVING CONDITIONS BY 6 PM. WINDS SHOULD BECOME ELY BY
MIDDAY AND STAY THAT WAY UNTIL OUTFLOW BOUNDARIES MOVE ACROSS
CAUSING VARIABLE WIND DIRECTIONS. BY THIS EVENING WINDS WILL BECOME
MORE SELY. ANOTHER DISTURBANCE MAY MOVE ACROSS AFTER MIDNIGHT
BRINGING A CHC OF SHOWERS AND POSSIBLY A TSTM. BY 12Z ON FRI COULD
SEE MORE STRATUS AND POSSIBLY SOME FOG.
&&
.HYDROLOGY...
ISSUED AT 305 AM MDT THU MAY 22 2014
STORMS THIS AFTERNOON WILL BE SLOWER MOVING SO THERE WILL BE A
HIGHER POTENTIAL FOR HEAVY RAINFALL IN SOME AREAS WITH UP TO 2
INCHES IN 45 MINUTES OR LESS. THE HEAVIEST RAINFALL WILL STAY OVER
THE PLAINS ALTHOUGH THERE COULD BE SOME SLOW MOVING TSTMS IN THE
FOOTHILLS WHICH COULD PRODUCE UP TO AN INCH OF RAIN IN 30 MINUTES IN
A FEW LOCATIONS.
STILL KEEPING A WATCHFUL EYE ON FRIDAY AND SATURDAY FOR HEAVY
RAINFALL FROM STORMS AS THE MOISTURE SURGE MOVES INTO THE STATE
FROM THE SOUTH. INSTABILITY WILL BE WEAKER BUT STILL EXPECTING
SLOWER MOVING STORMS. UPSLOPE FLOW SEEMS TO BE SLIGHTLY WEAKENING
AND A SURFACE TROUGH MAY ALTER THE UPSLOPE FLOW TO LITTLE OR NONE
AT TIMES.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...KRIEDERMAN
AVIATION...RPK
HYDROLOGY...KRIEDERMAN/RPK
AREA FORECAST DISCUSSION
NWS TAUNTON MA
744 PM EDT FRI MAY 23 2014
.SYNOPSIS...
A SERIES OF UPPER LEVEL DISTURBANCES WILL BRING A FEW ROUNDS OF
SHOWERS AND ISOLATED THUNDERSTORMS THROUGH SUNDAY. TURNING MILDER
SUNDAY THEN WARM AND DRY CONDITIONS EXPECTED FOR MEMORIAL DAY. A
WEAK FRONT MAY BRING SCATTERED SHOWERS TUESDAY INTO EARLY
WEDNESDAY ALONG WITH COOLER TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
7 PM UPDATE...
CONVERGENT BOUNDARY NOTED THROUGH THE CT-RIVER VALLEY COLLOCATED
WITH WEAK INSTABILITY BENEATH A REGION OF MODEST LIFT AND STEEPENING
MID-LEVEL LAPSE RATES AS NOTED BY THE PREVIOUS FORECASTER. EXPECTING
WIDESPREAD RAIN WITH EMBEDDED HEAVY SHOWERS AND THUNDERSTORMS
WHICH HAVE THE POTENTIAL OF PUTTING DOWN AN INCH OR MORE OF RAIN-
FALL IN ROUGHLY AN HOUR.
LOWER CONFIDENCE CONCERNING SEVERE WEATHER THREATS. MAIN CONCERN
IS WITH HEAVY RAIN AND SUBSEQUENT URBAN / POOR DRAINAGE FLOODING.
ALREADY REPORTS HAVE BEEN RECEIVED OF A COUPLE OF ROADS BECOMING
IMPASSIBLE WITH SIGNIFICANT RAINFALL AMOUNTS OF NEARLY HALF AN
INCH IN 5-MINUTES! VERY SLOW MOVEMENT OF THE STORMS EXACERBATES
THE FLOODING THREAT IN ADDITION TO THE LOW-LEVEL CONVERGENCE...AS
WELL AS STORM MERGERS.
FEEL THE HRRR HAS A GOOD HANDLE ON THE PRESENT SITUATION. THE HOPE
IS WITH THE MAIN MID-LEVEL IMPULSE DIGGING SE TOWARDS THE OFFSHORE
WATERS S OF NEW ENGLAND THAT SUBSIDENCE WILL PREVAIL IN A REGION
OF NEGATIVE VORTICITY ADVECTION /DOWNWARD COMPONENT - RIGHT HAND
RULE/. THUS ACTIVITY SHOULD CONCLUDE OVER THE NEXT COUPLE HOURS...
HOPEFULLY.
OTHER CONCERNS ARE WITH THE POTENTIAL FOR DENSE FOG ALONG SE MA
INCLUDING THE CAPE. SEEING A DECENT FOG BANK OFFSHORE OF NEW
ENGLAND APPROACHING W WITH THE EASTERLY FLOW. EXPECTING IMPACTS
TOWARDS 4Z INTO THE MORNING...BURNING OFF WITH SUNRISE EVER
GRADUALLY. WILL AVOID A SPECIAL WEATHER STATEMENT FOR NOW WITH THE
PRESENT WEATHER ACTIVITY.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY...
MID LEVEL TROF AXIS WILL BE MOVING E OF NEW ENG BUT COLD POOL
ALOFT REMAINS WITH 500 MB TEMPS -20 TO -21C. MARGINAL INSTABILITY
DEVELOPS IN THE WEST WHICH WILL LEAD TO SCT SHOWERS/TSTMS. LOW
LEVEL WINDS INDICATE A WEAK BOUNDARY ACROSS W ZONES WHICH MAY
PROVIDE A FOCUS FOR CONVECTION. LOCALLY HEAVY RAINFALL WILL BE
PRIMARY THREAT AS WINDS ALOFT REMAIN WEAK. ACROSS E NEW
ENG...JUST A FEW SHOWERS EXPECTED BUT NOT MUCH MORE THAN THAT
WITH LIMITED INSTABILITY. ANOTHER DAY WITH LOTS OF CLOUDS
ALTHOUGH SOME BREAKS OF SUN POSSIBLE...ESPECIALLY IN EASTERN NEW
ENG. HIGH TEMPS WILL BE MOSTLY IN THE 60S.
SATURDAY NIGHT...
SOME LINGERING CONVECTION POSSIBLE IN THE WEST IN THE
EVENING...OTHERWISE WEAK RIDGING MOVES INTO THE REGION WHICH
WILL BRING MAINLY DRY CONDITIONS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HEADLINES...
- SEA-BREEZE SUNDAY WILL BE THE FOCUS OF SHOWERS/THUNDERSTORMS
- MEMORIAL DAY MIX WITH BEST CONDITIONS SW WITH DISMAL WEATHER NE
- COLD FRONT AND WET WEATHER EXPECTED FOR TUESDAY
- SEASONABLE CONDITIONS AND BOUTS OF WET WEATHER INTO THE WEEKEND
/ OVERVIEW AND MODEL PREFERENCE...
IS THIS LATE MAY OR EARLY MARCH? PERSISTENT LOWER HEIGHTS ACROSS
GREENLAND STRENGTHEN THE NORTH-ATLANTIC RIDGE. AS SUCH THE LONGWAVE
PATTERN BUCKLES. SUBSEQUENTLY TROUGHING IS PREFERRED ALONG THE W-
PERIPHERY OF WHICH DISTURBANCES DIG SOUTHWARD RESULTING IN THE
CONTINUANCE OF COOLER WET WEATHER ACROSS A MAJORITY OF THE NE-CONUS
AGAINST RIDGING THROUGH THE MIDWEST AHEAD OF THE MIGRATING LOW INTO
THE CENTRAL CONUS. THIS PATTERN MAY LINGER FOR AWHILE INTO THE START
OF SUMMER.
WITH THE NAO EXHIBITING A NEAR-NEUTRAL TREND WITH ENSEMBLE MEMBERS
AND GREATER CONFIDENCE GAINED FROM BOTH GEFS/ECENS/NAEFS H5 MEANS OF
STRONGER REAR-TROUGHING INFLUENCE WITH A NW-SE STREAM OF THE W-
PERIPHERY ACROSS NEW ENGLAND...WILL PREVAIL WITH NEAR-SEASONABLE
CONDITIONS AND CHANCES OF WET-WEATHER KEEPING THE WARMER-RIDGING
PATTERN TO THE W. MODEL CONSENSUS IS PREFERRED THROUGH THE WEEKEND
BUT THEREAFTER ENSEMBLE MEAN TRENDS ARE RECOMMENDED.
/ DAY-TO-DAY DETAILS...
SUNDAY...
COMBINATION OF A SEA-BREEZE FRONT PROVIDING FORCING BENEATH CYCLONIC
FLOW...WEAK MID-LEVEL IMPULSES...AND THE LFQ OF THE UPPER-LEVEL JET
STREAK...LOOKS TO GENERATE LIFT TOWARDS SHOWERS AND THUNDERSTORMS BY
MIDDAY INTO EVENING ACROSS INTERIOR NEW ENGLAND /ESPECIALLY E/.
CHALLENGES IN FORECASTING EXACT OUTCOMES IS DIFFICULT AT MODELS
DIFFER ON INSTABILITY AND PRECIPITATION OUTPUT. NOTING CONSISTENCY
OF NW-SE UNIDIRECTIONAL SHEAR...FREEZING LVL HEIGHTS AROUND 8 KFT...
PWATS AROUND 0.75-INCHES...AND MINOR INSTABILITY...WET-WEATHER
ACTIVITY IS EXPECTED. A HEAVY RAIN / SMALL HAIL THREAT ALONG WITH
GUSTY WINDS IS POSSIBLE WITH ANY STORMS. MAIN CONCERN IS WITH ANY
TRAINING N TO S WITH THE MEAN-LAYER FLOW ALONG THE SEA-BREEZE FRONT.
EXPECTING ACTIVITY TO CONCLUDE OVERNIGHT WITH THE END OF DAYTIME
HEATING. WITH A STRONGER MID-LEVEL DISTURBANCE DIGGING TOWARDS NE
NEW ENGLAND INVOKING SW-FLOW...ANTICIPATE A DEFINING WARM-FRONTAL
BOUNDARY LIFTING NE OF THE REGION...PERHAPS DRAPED S ALONG THE
IMMEDIATE COAST W.
MONDAY /MEMORIAL DAY/...
WARM-FRONT SITUATES ACROSS NE NEW ENGLAND ALONG WHICH A STRONG MID-
LEVEL IMPULSE PROVIDES ENHANCED ASCENT TOWARDS THE DEVELOPMENT OF
WET-WEATHER. ITS EXTENT SW IS SPECULATIVE.
WITH THE BEST DYNAMICS NE AND MUCH OF OUR REGION BENEATH THE RFQ OF
THE UPPER-LEVEL JET...WILL KEEP THE DAYTIME FORECAST TIMEFRAME
MOSTLY DRY WITH THE EXPECTATION OF SOME LEVEL OF SUBSIDENCE. NW-FLOW
COULD IMPINGE UPON HIGHER TERRAIN UNDERGOING OROGRAPHIC LIFT BENEATH
CYCLONIC FLOW AND FALLING HEIGHTS RESULTING IN SHOWER DEVELOPMENT.
OVERALL...WETTER/COOLER/CLOUDIER TO THE NE WHEREAS THE BEST WARM-
SUNNY CONDITIONS ARE TO THE SW. EXPECT A NE-SW TEMPERATURE GRADIENT
WITH VALUES EXCEEDING 80-DEGREES OVER THE LOWER CT-VALLEY.
COLD FRONT ATTENDANT TO THE LOW PRES CENTER INVIGORATED BY THE MID-
LEVEL IMPULSE BEGINS TO SWEEP SE INTO THE FORECAST REGION. EXPECT AN
INCREASE IN WET-WEATHER CONDITIONS TOWARDS MORNING AS TEMPERATURES
PERHAPS COOL TOWARDS MIDNIGHT BUT THEN UNDERGO A NON-DIURNAL TREND
THEREAFTER WITH INCREASING SW-FLOW.
MIDWEEK TOWARDS THE WEEKEND...
MODEL SPREAD INCREASES LENDING TO UNCERTAINTY TOWARDS EXACT OUTCOMES
AND THUS ONE CAN ONLY SPECULATE. NO ONE MODEL IS PREFERRED.
ITS LIKELY A COLD FRONT AND ATTENDANT WET-WEATHER WILL SWEEP ACROSS
THE REGION TUESDAY. TIMING AND SPECIFIC IMPACTS ARE HIGHLY UNCERTAIN
AND THERE IS SOME QUESTION AS TO THE DIRECTION OF FLOW REARWARD OF
THE COLD FRONT...WHETHER NW OR NE. A PERIOD OF DRY WEATHER IS
POSSIBLE THROUGHOUT THE REMAINDER OF THE WEEK...BUT BENEATH CYCLONIC
FLOW THROUGH WHICH WEAK IMPULSES ARE LIKELY TO DIG SOUTH...EXPECT
INTERMITTENT BOUTS OF WET-WEATHER.
OF GREATER CERTAINTY IS THE FACT THAT THE CONTINUED INFLUENCE OF A
TROUGHING PATTERN THE W-PERIPHERY OF WHICH REMAINS SITUATED ACROSS
NEW ENGLAND WILL RESULT IN NEAR-SEASONABLE CONDITIONS. EXPECTING
SOME NORTHERLY COMPONENT OF FLOW TO KEEP COOLER WEATHER ACROSS THE
REGION. DO NOT BELIEVE THE PATTERN WILL SHIFT INTO NEXT WEEKEND.
HAVE A BAD FEELING THE TROUGH LINGERS FOR AWHILE LONGER RESULTING
IN PROLONGED COOL WEATHER.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...MODERATE CONFIDENCE.
MIX OF MVFR-IFR WITH SHRA/TSRA THROUGH THE CT-VALLEY. ACTIVITY
SHOULD DIMINISH TOWARDS 2Z. THEREAFTER FOCUS IS ON A IFR-VLIFR FOG
BANK AND LOW-STRATUS IMPACTING E/SE MA AROUND 4Z DIRECTED BY
E-WINDS.
IMPROVEMENT SATURDAY MORNING PRIOR TO THE DEVELOPMENT OF SHRA/
TSRA BY MIDDAY INTO AFTERNOON THE BETTER CHANCES OF WHICH WILL BE
ACROSS THE CT-VALLEY. MVFR-IFR IMPACTS POSSIBLE WITH ANY WET-
WEATHER. NE WIND GUSTS UP TO 25 KTS POSSIBLE AT TIMES...ESP
TOWARDS THE MORNING ACROSS THE CAPE WHICH MAY ACT TO DISPERSE THE
FOG. HAVE TRENDED ACCORDINGLY.
SHRA/TSRA CONCLUDES TOWARDS EVENING OVER THE CT-VALLEY. WILL
LIKELY SEE THE RE-EMERGENCE OF FOG TOWARDS SUNDAY MORNING.
KBOS TAF...MODERATE CONFIDENCE. WILL BRING THE LOW-STRATUS CLOUD
DECK IN AROUND 4Z BUT NOT ENOUGH CONFIDENCE TO PREVAIL WITH FOG.
KBDL TAF...MODERATE CONFIDENCE. SHRA/TSRA ENDING BY 2Z. NOT
ENTIRELY CERTAIN ON TIMING. EXPECT REDEVELOPMENT OF ACTIVITY INTO
THE MIDDAY/AFTERNOON HOURS ON SATURDAY.
OUTLOOK...SUNDAY THROUGH TUESDAY...
SUNDAY...MODERATE CONFIDENCE.
SEA-BREEZE PUSHING E WILL BE THE FOCUS FOR SHRA/TSRA ACROSS THE E/C
INTERIOR AS W/SW WINDS CONVERGE WITH WINDS FROM THE E. TEMPO MVFR-
IFR WITH ACTIVITY. THINKING ISOLATED TSRA. ACTIVITY CONCLUDES INTO
THE OVERNIGHT HOURS.
MONDAY...MODERATE CONFIDENCE.
WILL HOLD SW TERMINALS IN VFR WHEREAS TO THE NE EXPECT A MIX OF MVFR
TO LOW-VFR WITH THE POSSIBILITY OF -SHRA. SW FLOW PREVAILS. WILL SEE
INCREASING CHANCES FOR RAIN AHEAD OF A COLD FRONT TOWARDS TUESDAY
MORNING.
TUESDAY INTO WEDNESDAY...LOW CONFIDENCE.
COLD FRONT SWEEPING THROUGH THE TERMINALS THE TIMING AND IMPACTS OF
WHICH REMAIN UNCERTAIN. MIX OF MVFR-IFR CONDITIONS POSSIBLE ALONG
THE FRONT WITH WET-WEATHER. N-WINDS BEHIND THE FRONT THE DIRECTION
OF WHICH IS ALSO UNCERTAIN.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE.
LOW PRES PASSES S OF THE WATERS LATE TONIGHT AND SAT AND
INCREASING LOW LEVEL NE WINDS WILL LIKELY BRING A PERIOD OF G25
KT TO THE SOUTHERN WATERS LATE TONIGHT AND SAT MORNING ALONG WITH
BUILDING SEAS TO 5 FT SO WE ISSUED AN SCA. IT IS POSSIBLE SCA MAY
NEED TO BE EXPANDED TO NEARSHORE S COASTAL WATERS BUT NOT
CONFIDENT ENOUGH STRONGER WINDS WILL REACH THAT FAR N. WINDS
DIMINISH SAT AFTERNOON WITH LIGHT WINDS/SEAS SAT NIGHT AS WEAK
RIDGING DEVELOPS.
AREAS OF FOG ARE POSSIBLE TONIGHT WHICH COULD BE LOCALLY DENSE AT
TIMES.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY...MODERATE CONFIDENCE.
SEA-BREEZES ALONG THE IMMEDIATE SHORES WITH SOUTHERLY FLOW OVERALL.
INCLEMENT WEATHER MAINLY ACROSS THE INTERIOR. SEAS REMAINING BELOW 5
FEET.
MONDAY...MODERATE CONFIDENCE.
W/SW WINDS WITH GUSTS UP TO 25 KTS /ESP ALONG THE SHORE/. SEAS ON
THE OUTER-WATERS UP TO 5 FEET. SHOWERS POSSIBLE ACROSS THE E-WATERS
AROUND CAPE ANN.
TUESDAY INTO WEDNESDAY...LOW CONFIDENCE.
COLD FRONT SWEEPING ACROSS THE WATERS THE TIMING OF WHICH IS
UNCERTAIN. BREEZY SW WINDS ALONG AND AHEAD BACKING OUT OF THE N TO
THE REAR. WAVES ON THE OUTER WATERS ABOVE 5-FEET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TO 4 PM EDT SATURDAY FOR
ANZ254>256.
&&
$$
SYNOPSIS...KJC/SIPPRELL
NEAR TERM...KJC/SIPPRELL
SHORT TERM...KJC
LONG TERM...SIPPRELL
AVIATION...KJC/SIPPRELL
MARINE...KJC/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
335 PM EDT THU MAY 22 2014
.SYNOPSIS...
LOW PRESSURE WILL BRING OCCASIONAL SHOWERY WEATHER AND COOL
TEMPERATURES INTO SATURDAY. TURNING MILDER SUNDAY THEN WARM AND
DRY CONDITIONS EXPECTED FOR MEMORIAL DAY. A WEAK FRONT MAY BRING
SCATTERED SHOWERS TUESDAY INTO EARLY WEDNESDAY ALONG WITH COOLER
TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
BAND OF SHOWERS MOVING ACROSS E MA AND THE HRRR HAS THE SHOWERS
LINGERING ALONG THE COAST UNTIL 21-22Z. SCT STRONG TO SEVERE
STORMS ACROSS E NY AND E PA ARE FIRING IN AXIS OF MAX INSTABILITY
WITH MLCAPES UP TO 1500 J/KG. THERE IS NO SFC INSTABILITY ACROSS
SNE AND WE EXPECT CONVECTION TO WEAKEN AS IT MOVES INTO SNE
THROUGH THIS EVENING...WITH THE HRRR CONCENTRATING THE SHOWERS IN
THE WEST THIS EVENING.
LATER TONIGHT...THERE IS SOME MID LEVEL DRYING MOVING IN FROM THE
SW AND SNE WILL BE IN BETWEEN SHORTWAVES FOR A TIME SO IT COULD BE
MOSTLY DRY IN THE OVERNIGHT PERIOD. ABUNDANT LOW LEVEL MOISTURE
WILL LEAD TO AREAS OF STRATUS AND FOG.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
FRIDAY...
STRONGER SHORTWAVE WILL BE DIGGING SE FROM THE GT LAKES WITH SHARP
TROF APPROACHING FROM THE WEST. WHILE LOW PRES WILL BE CUTTING TO
THE S OF NEW ENG AN INVERTED TROF SETS UP ACROSS FAR W NEW ENG IN
RESPONSE TO THE STRONG SHORTWAVE. THIS IS WHERE WE EXPECT THE MAIN
FOCUS FOR SHOWERS TO BE...BUT SCT SHOWERS EXPECTED FURTHER TO THE
EAST AS MOISTURE DEEPENS WITH PERSISTENT QG FORCING. MODELS
INDICATE SOME WEAK SFC INSTABILITY IN THE WEST SO POTENTIAL FOR A
FEW TSTMS AS WELL. INCREASING LOW LEVEL EASTERLY FLOW WILL RESULT
IN COOLER TEMPS WITH MAXES UPPER 50S TO LOWER 60S.
FRIDAY NIGHT...
SHOWERS AND ISOLD TSTMS CONTINUE INTO THE EVENING AS THE TROF
MOVES ACROSS SNE WITH LOW PRES PASSING TO THE SE. MODELS KEEP THE
FOCUS IN WESTERN NEW ENG WHERE BEST LOW LEVEL CONVERGENCE AND MID
LEVEL OMEGA. AS THE TROF SHIFTS TO THE EAST OVERNIGHT A DECREASE
IN THE SHOWERS EXPECTED. MORE STRATUS AND PATCHY FOG LIKELY GIVEN
PERSISTENT LOW LEVEL MOISTURE AND EAST FLOW.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
- WEEKEND CHANCES OF SHOWERS/THUNDERSTORMS ACROSS THE INTERIOR
- NICE AND MILD FOR MEMORIAL DAY
- ANOTHER SHOT OF WET WEATHER FOR TUESDAY
- CLASH OF AIRMASSES AND UNCERTAIN WEATHER FOR THE REST OF THE WEEK
/ OVERVIEW AND MODEL PREFERENCE...
AN UNSTABLE LONG-TERM FORECAST BY NEXT WEEK AS EXHIBITED BY THE NAO
TREND. YESTERDAY NEAR-NEUTRAL WITH A NEGATIVE TREND HAS NOW SHIFTED
POSITIVE TOWARDS THE END OF MAY. THOUGH THE NAEFS/CANADIAN CONTINUES
TO EXHIBIT A POSITIVE HEIGHT ANOMALY OVER THE HUDSON BAY REGION...
THE TREND OF ABOVE AVERAGE TEMPERATURES HAS SOMEWHAT DIMINISHED.
SO CONSIDERING THE LOW LIFTING INTO THE CENTRAL PLAINS...THE RIDGE
SHOULD STRENGTHEN AHEAD. BUT AN ICELANDIC LOW PROVIDING THE MEANS OF
DOWNSTREAM BLOCKING APPEARS TO LIMIT THE PROGRESSIVENESS OF THE LONG-
WAVE FLOW AND THEREBY RESULTS IN TROUGHING LINGERING IN PROXIMITY TO
NEW ENGLAND AND ACROSS THE NW-ATLANTIC. THIS POINT IS EXACERBATED BY
A COMPARISON OF GEFS RUNS WHICH SHOWS A TREND TOWARDS A STRONGER
INFLUENCE OF THE W-PERIPHERY OF THE TROUGH RESULTING IN COOLER AIR
ALOFT ACROSS THE REGION. WPC NOTES THE ECENS IS DEEPER WITH THE
TROUGH WHEREAS THE GEFS IS SHARPER AND SLOWER. THE NAEFS IS THE
MIDDLE GROUND. THUS AM EXPECTING A CLASH OF AIRMASSES ACROSS THE NE-
CONUS WITH WARMER AIR SW AND COOLER AIR NE.
HAVE HIGH CONFIDENCE IN THE FORECAST THROUGH MONDAY USING A MODEL
CONSENSUS BLEND. SPREAD INCREASES BY TUESDAY...SO WILL LEAN MORE
TOWARDS MODEL ENSEMBLE MEANS KEEPING THE TROUGH IN CLOSER PROXIMITY
TO THE NE-CONUS AND HOLDING COOLER CONDITIONS ACROSS THE REGION AND
LIMITING THE INFLUENCE OF THE RIDGE FROM THE W.
/ DAY-TO-DAY DETAILS...
SATURDAY...
INVERTED TROUGH IS THE FOCUS OF LOCALIZED CONVERGENCE BENEATH WEAK
DISTURBANCES ALOFT WHICH WILL YIELD SOME MEASURE OF LIFT. NOTING
COOLER AIR WRAPPING REARWARD OF THE DEPARTING LOW. MID-LEVELS LAPSE
RATES SHOULD STEEPEN. LOOKING LIKE A CLOUDY COOL DAY WITH SCATTERED
SHOWERS AND THUNDERSTORMS THE BETTER CHANCES OF WHICH WILL BE ALONG
THE INVERTED TROUGH IN A REGION OF FAVORABLE LIFT AND INSTABILITY.
THAT AREA IS MAINLY ACROSS THE W-INTERIOR AND HUDSON RIVER VALLEY
REGION. ONSHORE E-FLOW WILL KEEP THE CENTRAL AND EASTERN FORECAST
AREA UNDER A MORE STABLE COOL AIRMASS THEREBY LIMITING ACTIVITY...
BUT NOT DOWN TO ZERO.
WITH ANY ACTIVITY...HEAVY RAIN AND GUSTY WINDS ARE POSSIBLE. WITH
THE DEEP-LAYER NNW FLOW ALONG THE INVERTED FRONT...STORMS MAY TRAIN
SO PERHAPS THERE IS A LOCALIZED FLOODING THREAT. THOUGH AGAIN...FEEL
THE BETTER CHANCES MAY REMAIN W OF NEW ENGLAND. WILL HAVE TO CLOSELY
WATCH OUT FOR IMPACTS ACROSS THE CT-RIVER VALLEY.
ACTIVITY CONCLUDES INTO EVENING. WILL HOLD WITH NEAR-SEASONABLE
TEMPERATURES OVER THE W AND CENTRAL INTERIOR OF NEW ENGLAND BUT
COOLER ALONG THE SHORES WITH ANTICIPATED SEA-BREEZE. ANTECEDENT
RAINS WITH LIGHT AND VARIABLE FLOW OVERNIGHT...IF CONDITIONS ARE
ALLOWED TO CLEAR OUT...THERE IS A GREATER PROPENSITY FOR DENSE FOG.
SUNDAY...
CONTINUED CYCLONIC FLOW BUT LESSER FORCING MECHANISMS. THE COLD POOL
LINGERS ALOFT CONTINUING THE PRESENCE OF STEEP MID-LVL LAPSE RATES.
AS THE BOUNDARY LAYER DESTABILIZES...EXPECT SHOWERS AND POSSIBLE
THUNDERSTORMS TO DEVELOP...BUT ON A MORE ISOLATED NATURE AND AGAIN
MAINLY ACROSS THE INTERIOR WITH THE LIKELIHOOD OF SEA-BREEZES ALONG
THE SHORES USHERING IN MORE STABLE AIR.
WILL PREVAIL WITH SEASONABLE TEMPERATURES. STORM MOTION SHOULD BE N
TO S. WITH ANY STORMS...HEAVY RAIN AND GUSTY WINDS ARE POSSIBLE. NO
CERTAINTY IN PINPOINTING WHERE AND WHEN STORMS WILL DEVELOP. WEATHER
SHOULD TURN QUIET OVERNIGHT AS DAYTIME HEATING CONCLUDES.
MONDAY...
WILL KEEP WITH A DRY FORECAST BUT WILL NEED TO MONITOR ADDITIONAL
ENERGY CYCLONICALLY DIGGING THROUGH THE PREVAILING TROUGH PATTERN
ACROSS N NEW ENGLAND. HAVE A FEELING THAT RIDGING WILL PREVAIL
BETWEEN THE DEPARTING WEEKEND DISTURBANCE AND THE EXPECTED DISTURBED
WEATHER FOR TUESDAY. THEREFORE...SUBSIDENCE PREVAILING WITH H85
TEMPERATURES AROUND +12C WILL YIELD WARM CONDITIONS WITH THE GREATER
CHANCE OF MOSTLY CLEAR CONDITIONS TO THE S AND W. THE SUBSEQUENT
BOUNDARY LAYER MIXING WILL YIELD BREEZY W-WINDS.
TUESDAY...
A FRONTAL DISTURBANCE WILL SWEEP ACROSS NEW ENGLAND FROM THE NW TO
SE. WILL SEE LIKELY SEE SHOWERS AND THUNDERSTORMS ALONG AND AHEAD
PENDING ON THE TIMING OF THE DISTURBANCE WHICH IS KEY TOWARDS
WHETHER THE BOUNDARY LAYER WILL DESTABILIZE ALONG AND AHEAD. SIGNALS
HAVE BEEN CONSISTENT WITHIN THE MODELS AS TO OUTCOMES...YET WILL
EXERCISE CAUTION AND CONCLUDE IN DISCUSSION WITH THE SPREAD AND
VARIANCE OF OUTCOMES.
REST OF THE WEEK...
TOWARDS MIDWEEK AM EXPECTING A WARM-FRONT ALONG THE MID-LEVEL CLASH
OF AIRMASSES ALONG WHICH DISTURBANCES WILL TRAIN THROUGH THE
CYCLONIC FLOW POTENTIALLY PROVIDING PERIODS OF INCLEMENT WEATHER.
TOO MUCH SPREAD AS TO THE INFLUENCE OF RIDGING AGAINST THE LINGERING
TROUGH LENDS TO A LOT OF UNCERTAINTY. AGAIN...WILL PREVAIL TOWARDS
MODEL ENSEMBLE MEANS.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH FRIDAY NIGHT/...MODERATE CONFIDENCE.
THROUGH 00Z...VFR/MVFR CIGS WILL LOWER TOWARD EVENING. SHOWERS
WILL EXIT EASTERN MA 20-21Z. SCT SHOWERS DEVELOPING IN THE
INTERIOR. BRIEF MVFR VSBY IN SHOWERS.
TONIGHT...MODERATE CONFIDENCE. CIGS DETERIORATING THIS EVENING
WITH WIDESPREAD IFR DEVELOPING. AREAS OF FOG DEVELOPING WITH BEST
CHANCE OF DENSE FOG AND LIFR VSBYS ALONG THE COAST.
FRIDAY...IFR/LIFR IN THE MORNING SHOULD LIFT TO MVFR IN THE
INTERIOR...BUT IFR CIGS MAY PERSIST IN THE COASTAL PLAIN.
IMPROVING VSBYS. SCT SHOWERS AND ISOLD TSTMS POSSIBLE...HIGHEST
PROBABILITY IN WESTERN NEW ENG.
FRI NIGHT...WIDESPREAD IFR REDEVELOPING WITH AREAS OF FOG. SCT TO
NUMEROUS SHOWERS IN THE EVENING.
KBOS TAF...VFR CONDITIONS ARE TEMPORARY AND EXPECT IFR CIGS TO
REDEVELOP BY THIS EVENING WITH FOG DEVELOPING AS WELL. LOW
CONFIDENCE ON TIMING AND HOW LOW VSBYS WILL GET.
KBDL TAF...MODERATE CONFIDENCE IN TAF. CONDITIONS LOWERING TO
MVFR/IFR. LOW CONFIDENCE ON TIMING.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SATURDAY...MODERATE CONFIDENCE.
BKN LOW-END VFR CIGS. SCT -SHRA/TSRA THE BETTER CHANCE OF WHICH WILL
BE ACROSS W-INTERIOR NEW ENGLAND TOWARDS THE HUDSON RIVER VALLEY.
TEMPO IFR WITH TSRA WITH +RA AND GUSTY WINDS. SEA-BREEZES ALONG THE
SHORES. WITH ACTIVITY CLEARING OVERNIGHT...IF WINDS BECOME LIGHT...
DENSE IFR FOG POSSIBLE.
SUNDAY...MODERATE CONFIDENCE.
BKN LOW-END VFR CIGS. ISOLATED -SHRA/TSRA ACROSS INTERIOR NEW
ENGLAND. SEA-BREEZES ALONG THE SHORES. ACTIVITY CONCLUDES OVERNIGHT.
MONDAY...LOW CONFIDENCE.
WILL CONTINUE TO HOLD VFR WITH GUSTY W-WINDS UP TO AROUND 25 KTS.
TUESDAY...LOW CONFIDENCE.
CONDITIONS DETERIORATING BY MORNING. WIDESPREAD RAIN WITH EMBEDDED
HEAVIER SHRA AND POSSIBLE TSRA. WILL SEE A COLD FRONT SWEEP ACROSS
THE TERMINALS. TERMINALS BEGINNING TO IMPROVE W TO E BY EVENING.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH FRIDAY NIGHT/...HIGH CONFIDENCE.
WINDS AND SEAS BELOW SCA THRESHOLDS THROUGH FRI EVENING WITH
EASTERLY FLOW. BUT CANT RULE OUT MARGINAL SCA CONDITIONS LATE FRI
NIGHT AS LOW LEVEL NE FLOW INCREASES AS LOW PRES PASSES TO THE
SOUTH. G20-25 KT AND 5 FT SEAS POSSIBLE FOR WATERS SE OF CAPE
COD.
THE MAIN CONCERN ON THE WATERS IS FOR AREAS OF
FOG WHICH COULD BE LOCALLY DENSE AT TIMES...PARTICULARLY DURING
THE LATE NIGHT/EARLY MORNING HOURS.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SATURDAY INTO SUNDAY...MODERATE CONFIDENCE.
WHILE DAILY OCCURRENCES OF SEA-BREEZES ALONG THE SHORES ARE TO BE
EXPECTED...WINDS OVERALL INITIALLY OUT OF THE NE WILL VEER OUT OF
THE SW WITH TIME. SEAS TO REMAIN BELOW 5 FEET. DENSE FOG WILL BE
POSSIBLE ACROSS THE WATERS SATURDAY NIGHT INTO SUNDAY MORNING
RESULTING IN SIGNIFICANT VISIBILITY RESTRICTIONS.
MONDAY...LOW CONFIDENCE.
W/SW WINDS WITH GUSTS UP TO 25 KTS. SEAS ON THE OUTER-WATERS
GETTING UP TO 5 FEET.
TUESDAY...LOW CONFIDENCE.
INCREASING RAIN CHANCES AS A FRONT SLIDES ACROSS THE WATERS LATE.
WILL SEE SW WINDS BACK OUT OF THE NW WITH FRONTAL PASSAGE. WAVES
GETTING UP TO 5 FEET ON THE OUTER WATERS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KJC/SIPPRELL
NEAR TERM...KJC
SHORT TERM...KJC
LONG TERM...SIPPRELL
AVIATION...KJC/SIPPRELL
MARINE...KJC/SIPPRELL
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
150 PM CDT THU MAY 22 2014
.DISCUSSION...
1158 AM CDT
MAIN UPDATES THIS MORNING WERE TO INCREASE CLOUD COVER...AND MAKE
MINOR ADJUSTMENTS TO TEMP TRENDS.
LATEST SATELLITE IMAGERY DEPICTING RAPIDLY WEAKENING SYSTEM MOVING
EAST INTO WESTERN ILLINOIS AT THIS TIME. ALTHOUGH
WEAKENING...STILL PROVIDING EXPANSIVE AND DENSE CLOUD SHIELD
ACROSS THE REGION. PREVIOUS FORECAST WAS ON TRACK WITH INCREASING
CLOUD COVER THROUGH MID DAY...BUT DID INCREASE SLIGHTLY MORE MAINLY
ACROSS THE SOUTHERN CWA WHERE A PERIOD OF MOSTLY CLOUD SKIES WILL
BE OBSERVED. EXPECT THIS CLOUD SHIELD TO THIN THROUGH MID
AFTERNOON WITH A RETURN TO MORE SUNNY SKIES BEFORE SUNSET.
OUTSIDE OF TEMPS NEAR THE LAKE...CURRENT FORECAST HIGH TEMPS OF
LOWER 70S STILL ON TRACK. PERSISTENT ONSHORE FLOW KEEPING AREAS
NEAR THE LAKE RATHER COOL...WITH UPPER 50S CURRENTLY BEING
REPORTED. DID ADJUST TEMP TRENDS INTO THE AFTERNOON...AND FEEL
THAT MOST LOCATIONS NEAR THE LAKE WILL STRUGGLE TO RISE MUCH FROM
THE UPPER 50S/AROUND 60 THIS AFTERNOON.
RODRIGUEZ
//PREV DISCUSSION...
306 AM CDT
A QUIET END TO THIS WEEK OFFERS MAINLY ONLY TEMPERATURE FORECAST
CHALLENGES. WHILE THERE ARE SMALL CHANCES OF THUNDERSTORMS FORECAST
FROM SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...THE REGIME FORECAST IS
ONE THAT KEEPS THE PROBABILITY LOW OF ANY HIGH IMPACT WEATHER THROUGH
THE HOLIDAY.
TODAY...
AN UPPER LOW ACROSS EASTERN ONTARIO THIS MORNING WILL CONTINUE TO
USHER A SURFACE COLD FRONT SOUTH FROM CENTRAL ILLINOIS AND INDIANA
TODAY. DAMPENED UPPER RIDGING WILL REMAIN IN PLACE FROM THE SOUTHERN
U.S. THROUGH THE MISSOURI RIVER VALLEY TODAY. WITH A STRONG UPPER
JET BETWEEN THESE TWO UPPER FEATURES...BROAD WEAK ASCENT WITHIN THE
RIGHT ENTRANCE REGION AND A SHEARED SHORT WAVE SHOULD SUPPORT HIGH
CLOUDS TO SPREAD ACROSS THE FORECAST AREA LATE THIS MORNING INTO THE
AFTERNOON. THIS IS LIKELY TO BE THICKER IN THE SOUTHERN FORECAST
AREA AND HAVE INCREASED FORECAST CLOUD COVER MORE SO THERE...BUT AT
LEAST SOME AREA WIDE. TEMPERATURES WILL LIKELY BE EFFECTED SLIGHTLY
BY THIS...ALTHOUGH COOLING WITHIN/AT THE TOP OF THE MIXED LAYER FROM
YESTERDAY WILL BE THE PRIMARY REASON FOR COOLER HIGHS. ONSHORE FLOW
WILL DEVELOP BY MID-MORNING WITH COOLER TEMPERATURES NEAR THE LAKE.
EXPECT THAT THE THERMAL DIFFERENCE BETWEEN DOWNTOWN CHICAGO AND FAR
WESTERN SUBURBS TO BE 10-12 DEGREES...NEAR THE LATE MAY CLIMO NORMAL
WITH ONSHORE FLOW ALL DAY.
TONIGHT THROUGH FRIDAY NIGHT...
A SURFACE HIGH WILL CENTER OVER THE AREA OFFERING LIGHT WIND FLOW.
BY LATE THIS EVENING AND THROUGH THIS PERIOD THERE LOOKS TO BE
LITTLE IN THE WAY OF CLOUDS. ONSHORE FLOW WILL REDEVELOP DURING
FRIDAY KEEPING LAKESIDE AREAS IN THE LOWER 60S OR SO. BOTH NIGHTS
LOOK TO SUPPORT 40S FOR LATE NIGHT LOWS IN THE MOST AREAS...WITH
SOME OF THE COOLER SPOTS REALIZING LOWER 40S ON FRIDAY NIGHT.
THE HOLIDAY WEEKEND INTO NEXT WEEK...
THE MEANDERING UPPER LOW ACROSS THE SOUTHWEST U.S. WILL DRIFT
NORTHEAST AS A RESULT OF BEING DISJOINTED FROM THE STRONGER WESTERLY
JET ACROSS THE U.S./CANADIAN BORDER. SUCH A CLOSED FEATURE IN THAT
PATTERN SEEMS TO MORE OFTEN THAN NOT MOVE SLOWER THAN INITIALLY
DEPICTED BY LONG RANGE GUIDANCE. WARM ADVECTION AND PRECIPITABLE
WATER INCREASE ARE FORECAST TO OCCUR SUNDAY AND MOST DETERMINISTIC
AND ENSEMBLE GUIDANCE HINT AT SOME CHANCE OF PRECIPITATION IN THE
REGION...THOUGH MAINLY NORTHWEST OF THE AREA. THE UPPER RIDGE IS
FORECAST TO RE-AMPLIFY OVER THE AREA ON THE HOLIDAY WITH A WEAK
SURFACE FRONT TO THE NORTH. IF THAT PATTERN WERE TO UNFOLD...THUNDER
CHANCES LOOK MINIMAL OVER THE FORECAST AREA. HAVE DECREASED THE
COVERAGE AND MAGNITUDE OF POPS PROVIDED BY A MODEL/PREVIOUS FORECAST
BLEND FOR THE HOLIDAY AND TUESDAY. THE UPPER LOW OR OPEN WAVE SHOULD
SHIFT EAST DURING THE MIDDLE OF THE WEEK...THOUGH THE 22.00 GFS
ACTUALLY TURNS THIS SOUTHEAST WITH BASICALLY VERY LITTLE PRECIP
CHANCES DURING MIDWEEK. WHILE THAT SEEMS A LITTLE SUSPECT...THE
CHANCES FOR RAIN LOOK SMALL AT THIS DISTANCE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NELY-ELY WINDS WITH SUSTAINED SPEEDS LESS THAN 10 KT...BECOMING
LGT/VRBL AT SUNSET.
* NORTHEAST WINDS LESS THAN 10 KT FRIDAY.
KREIN
//DISCUSSION...UPDATED 18Z...
WINDS WILL BE THE PRIMARY CONCERN FOR THE NEXT 24-36 HOURS. WITH
HIGH PRESSURE EXTENDING OVER THE UPPER MISSOURI VALLEY AND LOW
PRESSURE OVER NEW ENGLAND...WINDS OVER THE REGION HAVE BECOME
GENERALLY NORTHWESTERLY AND LIGHT. HOWEVER...THE WEAK GRADIENT AND
LARGE TEMPERATURE DIFFERENCE BETWEEN THE COLD LAKE MICHIGAN WATER
AND LAND HAS SET UP A LAKE BREEZE WHICH HAS ALREADY PUSHED THROUGH
ORD/MDW/GYY...TURNING WINDS ELY AT ORD/MDW AND NLY AT GYY. DPA/RFD
SHOULD NOT BE AFFECTED AND WINDS WILL REMAIN MORE REFLECTIVE OF
THE SYNOPTIC PATTERN. THROUGH THE EVENING...THE HIGH WILL MOVE
ACROSS THE TERMINAL AREAS AND WINDS SHOULD BECOME LGT/VRBL. BY
TOMORROW MORNING...WITH THE HIGH PUSHING OVER THE WESTERN GREAT
LAKES REGION...WINDS WILL BECOME SYNOPTICALLY NORTHEASTERLY...SO
ANY LAKE EFFECT WILL BE NEGLIGIBLE. SUSTAINED WIND SPEEDS SHOULD
INCREASE THROUGH THE MORNING...BUT GENERALLY REMAIN LESS THAN
10KT.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. EARLY EVE NORTHEAST WINDS LIKELY BECOME LIGHT/VRB.
SATURDAY...VFR. EASTERLY WINDS THROUGH EVENING.
SUNDAY...SCHC TSRA...OTHERWISE MAINLY VFR.
MONDAY...CHC TSRA...OTHERWISE MAINLY VFR.
TUESDAY...SCHC TSRA...OTHERWISE MAINLY VFR. NE WIND SHIFT PSBL.
WEDNESDAY...CHC TSRA. NORTHEAST WINDS PSBL.
RC
&&
.MARINE...
148 PM CDT
A LARGE AREA OF HIGH PRESSURE...CURRENTLY CENTERED ACROSS THE UPPER
MIDWEST...WILL GRADUALLY SHIFT EASTWARD OVER LAKE MICHIGAN BY LATE
FRIDAY INTO SATURDAY. THIS WILL RESULT IN FAIRLY LIGHT WINDS ACROSS
THE LAKE...WITH LAKE BREEZE INFLUENCES LIKELY TO PRODUCE ONSHORE
FLOW DURING THE DAYS FRIDAY AND SATURDAY. ONCE THE HIGH SHIFTS EAST
OF THE LAKE ON SUNDAY...EXPECT THE WINDS TO SHIFT BACK OUT OF THE
SOUTH INTO EARLY NEXT WEEK. WIND SPEEDS MAY INCREASE UP TO AROUND 20
KT OR SO FOR A PERIOD INTO MONDAY AS IT APPEARS THE PRESSURE
GRADIENT WILL STRENGTHEN IN RESPONSE TO A TOUGH OF LOW PRESSURE
POSSIBLY TRACKING ACROSS WESTERN ONTARIO AND THE UPPER MIDWEST. THIS
SYSTEM LOOKS TO ALSO INCREASE THE CHANCES OF MORE SHOWER AND
THUNDERSTORM ACTIVITY OVER THE LAKE LATER SUNDAY NIGHT AND MONDAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1250 PM CDT Thu May 22 2014
.DISCUSSION...
ISSUED 1046 AM CDT Thu May 22 2014
High pressure building back into the region and a more stable
airmass dominating. MCS remnants to the west running into a drier
airmass as well and precip is dwindling as it crosses the
Mississippi River. Expect the trend to continue. Keeping the
forecast mainly dry with a slight chance mention for the west this
afternoon, though a stray sprinkle or two may remain possible
through the late morning hours. Forecast temperatures are on track
under mostly cloudy skies as plenty of mid clouds stream into the
FA remnants of the MCS. No updates are anticipated at this time.
&&
.AVIATION...
ISSUED 1246 PM CDT Thu May 22 2014
Not much of a shift in the forecast. VFR throughout. Decaying MCS
to the west bringing in a chance for maybe VCSH in PIA but keeping
predominant precip out for now. Lightning activity is to the west
and expected to propagate to the SE, missing ILX terminals.
Some AC out there in addition to some cirrus keeping decks well
within VFR conditions. Northerly winds pick up a more NErly fetch
in the overnight hours and sct high clouds continue through
morning.
HJS
&&
.PREV DISCUSSION...
ISSUED 319 AM CDT Thu May 22 2014
SHORT TERM...Today through Saturday
07z/2am surface analysis shows cold front extending from near
Paris to just south of Taylorville. Ahead of the boundary, a
warm/humid airmass persists across southeast Illinois where
dewpoints are in the middle to upper 60s. Meanwhile behind the
front, northerly winds have brought considerably drier air into
much of central Illinois, with dewpoints dropping into the upper
40s and lower 50s north of I-72. Front will continue to sag
southward today, eventually dropping south of the Ohio River by
late afternoon. As a result, cooler and less humid conditions can
be expected with high temps remaining in the 70s. Precip chances
will develop along/ahead of the front this afternoon, but will
remain south of the KILX CWA. The only potential fly in the
ointment will be a weak short-wave currently tracking out of
Colorado. As this feature approaches from the west, a few
showers/storms may spread into the far W/SW CWA this afternoon and
evening. While most models keep central Illinois completely dry
today and tonight, higher-res models such as the RAP and HRRR show
precip associated with the wave moving across central/southern
Iowa and approaching from the west this afternoon. Have therefore
included a slight chance POP along/southwest of a Rushville to
Jacksonville line this afternoon into tonight.
High pressure will build into the southern Great Lakes by the end
of the week, pushing the front even further south/southwest. With
dry N/NE flow around the high, sunny skies will be the rule on
both Friday and Saturday with temperatures in the 70s and low
relative humidity values.
LONG TERM...Sunday through Wednesday
As high slides off to the east, remnants of old frontal boundary
will return northward on Sunday. Models continue to produce some
QPF across the area as the warmer air returns: however, with only
meager forcing along a dissipating boundary and rising upper heights,
think this is overdone. Upper ridge will build in earnest across
the Midwest early next week, leading to temperatures climbing well
into the 80s. Big question will be how fast the ridge breaks down
as cut-off low currently over southern California works its way
eastward. GFS has been the slowest model with this process for the
past few runs and its 00z May 22 solution is no exception.
Meanwhile, ECMWF had previously been faster, but its latest run
has slowed down and now keeps wave west of Illinois until
Wednesday. Given high-amplitude upper ridge in place over the
Midwest, continue to favor a slower solution. Even though both the
GFS and ECMWF delay the arrival of the upper low until mid-week,
both produce QPF across the area on Monday and Tuesday. Given high
upper heights and lack of forcing, think little more than isolated
diurnal convection will fire on either of those two days. As such,
have kept the forecast dry until Wednesday when better forcing
arrives with the approaching upper low.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1101 AM CDT THU MAY 22 2014
.DISCUSSION...
306 AM CDT
A QUIET END TO THIS WEEK OFFERS MAINLY ONLY TEMPERATURE FORECAST
CHALLENGES. WHILE THERE ARE SMALL CHANCES OF THUNDERSTORMS FORECAST
FROM SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...THE REGIME FORECAST IS
ONE THAT KEEPS THE PROBABILITY LOW OF ANY HIGH IMPACT WEATHER THROUGH
THE HOLIDAY.
TODAY...
AN UPPER LOW ACROSS EASTERN ONTARIO THIS MORNING WILL CONTINUE TO
USHER A SURFACE COLD FRONT SOUTH FROM CENTRAL ILLINOIS AND INDIANA
TODAY. DAMPENED UPPER RIDGING WILL REMAIN IN PLACE FROM THE SOUTHERN
U.S. THROUGH THE MISSOURI RIVER VALLEY TODAY. WITH A STRONG UPPER
JET BETWEEN THESE TWO UPPER FEATURES...BROAD WEAK ASCENT WITHIN THE
RIGHT ENTRANCE REGION AND A SHEARED SHORT WAVE SHOULD SUPPORT HIGH
CLOUDS TO SPREAD ACROSS THE FORECAST AREA LATE THIS MORNING INTO THE
AFTERNOON. THIS IS LIKELY TO BE THICKER IN THE SOUTHERN FORECAST
AREA AND HAVE INCREASED FORECAST CLOUD COVER MORE SO THERE...BUT AT
LEAST SOME AREA WIDE. TEMPERATURES WILL LIKELY BE EFFECTED SLIGHTLY
BY THIS...ALTHOUGH COOLING WITHIN/AT THE TOP OF THE MIXED LAYER FROM
YESTERDAY WILL BE THE PRIMARY REASON FOR COOLER HIGHS. ONSHORE FLOW
WILL DEVELOP BY MID-MORNING WITH COOLER TEMPERATURES NEAR THE LAKE.
EXPECT THAT THE THERMAL DIFFERENCE BETWEEN DOWNTOWN CHICAGO AND FAR
WESTERN SUBURBS TO BE 10-12 DEGREES...NEAR THE LATE MAY CLIMO NORMAL
WITH ONSHORE FLOW ALL DAY.
TONIGHT THROUGH FRIDAY NIGHT...
A SURFACE HIGH WILL CENTER OVER THE AREA OFFERING LIGHT WIND FLOW.
BY LATE THIS EVENING AND THROUGH THIS PERIOD THERE LOOKS TO BE
LITTLE IN THE WAY OF CLOUDS. ONSHORE FLOW WILL REDEVELOP DURING
FRIDAY KEEPING LAKESIDE AREAS IN THE LOWER 60S OR SO. BOTH NIGHTS
LOOK TO SUPPORT 40S FOR LATE NIGHT LOWS IN THE MOST AREAS...WITH
SOME OF THE COOLER SPOTS REALIZING LOWER 40S ON FRIDAY NIGHT.
THE HOLIDAY WEEKEND INTO NEXT WEEK...
THE MEANDERING UPPER LOW ACROSS THE SOUTHWEST U.S. WILL DRIFT
NORTHEAST AS A RESULT OF BEING DISJOINTED FROM THE STRONGER WESTERLY
JET ACROSS THE U.S./CANADIAN BORDER. SUCH A CLOSED FEATURE IN THAT
PATTERN SEEMS TO MORE OFTEN THAN NOT MOVE SLOWER THAN INITIALLY
DEPICTED BY LONG RANGE GUIDANCE. WARM ADVECTION AND PRECIPITABLE
WATER INCREASE ARE FORECAST TO OCCUR SUNDAY AND MOST DETERMINISTIC
AND ENSEMBLE GUIDANCE HINT AT SOME CHANCE OF PRECIPITATION IN THE
REGION...THOUGH MAINLY NORTHWEST OF THE AREA. THE UPPER RIDGE IS
FORECAST TO RE-AMPLIFY OVER THE AREA ON THE HOLIDAY WITH A WEAK
SURFACE FRONT TO THE NORTH. IF THAT PATTERN WERE TO UNFOLD...THUNDER
CHANCES LOOK MINIMAL OVER THE FORECAST AREA. HAVE DECREASED THE
COVERAGE AND MAGNITUDE OF POPS PROVIDED BY A MODEL/PREVIOUS FORECAST
BLEND FOR THE HOLIDAY AND TUESDAY. THE UPPER LOW OR OPEN WAVE SHOULD
SHIFT EAST DURING THE MIDDLE OF THE WEEK...THOUGH THE 22.00 GFS
ACTUALLY TURNS THIS SOUTHEAST WITH BASICALLY VERY LITTLE PRECIP
CHANCES DURING MIDWEEK. WHILE THAT SEEMS A LITTLE SUSPECT...THE
CHANCES FOR RAIN LOOK SMALL AT THIS DISTANCE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* NELY-ELY WINDS WITH SUSTAINED SPEEDS LESS THAN 10 KT THROUGH
EARLY EVENING.
* NORTHEAST WINDS FRIDAY.
KREIN
//DISCUSSION...UPDATED 12Z...
NO SIGNIFICANT AVIATION IMPACTS OVER THE NEXT 24 TO 30 HOURS UNDER
THE INFLUENCE OF DRY CANADIAN HIGH PRESSURE WITH VFR CONDITIONS
THROUGHOUT. LIGHT NORTHERLY WINDS EARLY THIS MORNING ARE EXPECTED
TO QUICKLY VEER NORTHEAST BY MID TO LATE MORNING AT ORD/MDW/GYY
WITH LAKE BREEZE PROBABLY MAKING IT TO DPA IN MID TO LATE
AFTERNOON. WINDS AT ORD/MDW/GYY ARE LIKELY TO VEER MORE TOWARD
EAST NORTHEAST OR EAST BY MID TO LATE AFTERNOON. SUSTAINED SPEEDS
AT ORD/MDW SHOULD AT LEAST OCCASIONALLY BE AROUND 10 KT FROM MID-
LATE AM THROUGH EARLY THIS EVENING. WINDS IN NORTH CENTRAL
ILLINOIS INCLUDING RFD WILL BACK FROM NORTHERLY TO NORTHWEST BY
MID DAY. LIGHT AND VARIABLE WINDS ARE EXPECTED AFTER SUNSET THIS
EVENING AS RIDGE AXIS MOVES OVERHEAD. LIGHT NORTH AND NORTHEAST
WINDS EARLY FRIDAY MORNING WILL LIKELY BECOME NORTHEAST AT ALL
TERMINALS AND INCREASE SOME BY MID TO LATE MORNING.
RC
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN WIND TRENDS.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. EARLY EVE NORTHEAST WINDS LIKELY BECOME LIGHT/VRB.
SATURDAY...VFR. EASTERLY WINDS THROUGH EVENING.
SUNDAY...SCHC TSRA...OTHERWISE MAINLY VFR.
MONDAY...CHC TSRA...OTHERWISE MAINLY VFR.
TUESDAY...SCHC TSRA...OTHERWISE MAINLY VFR. NE WIND SHIFT PSBL.
WEDNESDAY...CHC TSRA. NORTHEAST WINDS PSBL.
RC
&&
.MARINE...
301 AM CDT
EXPANSIVE HIGH PRESSURE SPREADING SOUTHEAST FROM THE UPPER MIDWEST
ACROSS THE GREAT LAKES REGION TODAY THROUGH SATURDAY WILL RESULT
IN AN EXTENDED PERIOD OF FAIRLY LIGHT WINDS AND LOW WAVES. WINDS
WILL INITIALLY BE NORTH AND NORTHWEST BUT TREND TOWARD GREATER
VARIABILITY LATER TODAY THROUGH SATURDAY AS THE HIGH BECOMES
PRIMARILY CENTERED OVER LAKE MICHIGAN. WINDS IN THE NEARSHORE
AREAS WILL BE CONTROLLED BY LAKE BREEZE INFLUENCES.
THE HIGH WILL THEN SLIDE EAST SUNDAY AND OFF THE ATLANTIC COAST ON
SUNDAY NIGHT...RESULTING IN INCREASING SOUTHERLY WINDS. AS BROAD
LOW PRESSURE OVER THE PLAINS AND CANADIAN PRAIRIES ON SUNDAY
CONSOLIDATES INTO A LOW CENTER NORTH OF THE LAKES ON
MONDAY...GUSTS COULD REACH UP TO 25 KT FOR A PERIOD LATE SUNDAY
INTO MONDAY DESPITE A VERY WARM AIR MASS MOVING OVER THE LAKE.
WITH THIS WARM AND MOIST AIR MASS WILL ALSO COME AN INCREASING
CHANCE FOR THUNDERSTORMS LATE SUNDAY THROUGH MONDAY EVENING.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1054 AM CDT Thu May 22 2014
.DISCUSSION...
ISSUED 1046 AM CDT Thu May 22 2014
High pressure building back into the region and a more stable
airmass dominating. MCS remnants to the west running into a drier
airmass as well and precip is dwindling as it crosses the
Mississippi River. Expect the trend to continue. Keeping the
forecast mainly dry with a slight chance mention for the west this
afternoon, though a stray sprinkle or two may remain possible
through the late morning hours. Forecast temperatures are on track
under mostly cloudy skies as plenty of mid clouds stream into the
FA remnants of the MCS. No updates are anticipated at this time.
HJS
&&
.AVIATION...
ISSUED 655 AM CDT Thu May 22 2014
VFR conditions should prevail across the central IL airports
through 12Z/7 am Friday. Mid and high clouds to spread ese across
central IL during the day as ceilings lower to 7-12k ft. These
clouds will then scatter out from north to south during overnight
occurring near I-74 first. Isolated showers and thunderstorms
should stay sw of SPI this afternoon and evening. Thunderstorms
with MCS over nw MO, ne KS, se NE and sw IA and associated with a
short wave to track ese across northern MO and sw IL today and
evening along frontal boundary that has pushed south of I-70 early
this morning and will continue to stay south of central IL thru
tonight. NNW winds will be near 10 kts today and veer NNE tonight
and diminish to around 5 kts.
07
&&
.PREV DISCUSSION...
ISSUED 319 AM CDT Thu May 22 2014
SHORT TERM...Today through Saturday
07z/2am surface analysis shows cold front extending from near
Paris to just south of Taylorville. Ahead of the boundary, a
warm/humid airmass persists across southeast Illinois where
dewpoints are in the middle to upper 60s. Meanwhile behind the
front, northerly winds have brought considerably drier air into
much of central Illinois, with dewpoints dropping into the upper
40s and lower 50s north of I-72. Front will continue to sag
southward today, eventually dropping south of the Ohio River by
late afternoon. As a result, cooler and less humid conditions can
be expected with high temps remaining in the 70s. Precip chances
will develop along/ahead of the front this afternoon, but will
remain south of the KILX CWA. The only potential fly in the
ointment will be a weak short-wave currently tracking out of
Colorado. As this feature approaches from the west, a few
showers/storms may spread into the far W/SW CWA this afternoon and
evening. While most models keep central Illinois completely dry
today and tonight, higher-res models such as the RAP and HRRR show
precip associated with the wave moving across central/southern
Iowa and approaching from the west this afternoon. Have therefore
included a slight chance POP along/southwest of a Rushville to
Jacksonville line this afternoon into tonight.
High pressure will build into the southern Great Lakes by the end
of the week, pushing the front even further south/southwest. With
dry N/NE flow around the high, sunny skies will be the rule on
both Friday and Saturday with temperatures in the 70s and low
relative humidity values.
LONG TERM...Sunday through Wednesday
As high slides off to the east, remnants of old frontal boundary
will return northward on Sunday. Models continue to produce some
QPF across the area as the warmer air returns: however, with only
meager forcing along a dissipating boundary and rising upper heights,
think this is overdone. Upper ridge will build in earnest across
the Midwest early next week, leading to temperatures climbing well
into the 80s. Big question will be how fast the ridge breaks down
as cut-off low currently over southern California works its way
eastward. GFS has been the slowest model with this process for the
past few runs and its 00z May 22 solution is no exception.
Meanwhile, ECMWF had previously been faster, but its latest run
has slowed down and now keeps wave west of Illinois until
Wednesday. Given high-amplitude upper ridge in place over the
Midwest, continue to favor a slower solution. Even though both the
GFS and ECMWF delay the arrival of the upper low until mid-week,
both produce QPF across the area on Monday and Tuesday. Given high
upper heights and lack of forcing, think little more than isolated
diurnal convection will fire on either of those two days. As such,
have kept the forecast dry until Wednesday when better forcing
arrives with the approaching upper low.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
901 AM CDT THU MAY 22 2014
.DISCUSSION...
306 AM CDT
A QUIET END TO THIS WEEK OFFERS MAINLY ONLY TEMPERATURE FORECAST
CHALLENGES. WHILE THERE ARE SMALL CHANCES OF THUNDERSTORMS FORECAST
FROM SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...THE REGIME FORECAST IS
ONE THAT KEEPS THE PROBABILITY LOW OF ANY HIGH IMPACT WEATHER THROUGH
THE HOLIDAY.
TODAY...
AN UPPER LOW ACROSS EASTERN ONTARIO THIS MORNING WILL CONTINUE TO
USHER A SURFACE COLD FRONT SOUTH FROM CENTRAL ILLINOIS AND INDIANA
TODAY. DAMPENED UPPER RIDGING WILL REMAIN IN PLACE FROM THE SOUTHERN
U.S. THROUGH THE MISSOURI RIVER VALLEY TODAY. WITH A STRONG UPPER
JET BETWEEN THESE TWO UPPER FEATURES...BROAD WEAK ASCENT WITHIN THE
RIGHT ENTRANCE REGION AND A SHEARED SHORT WAVE SHOULD SUPPORT HIGH
CLOUDS TO SPREAD ACROSS THE FORECAST AREA LATE THIS MORNING INTO THE
AFTERNOON. THIS IS LIKELY TO BE THICKER IN THE SOUTHERN FORECAST
AREA AND HAVE INCREASED FORECAST CLOUD COVER MORE SO THERE...BUT AT
LEAST SOME AREA WIDE. TEMPERATURES WILL LIKELY BE EFFECTED SLIGHTLY
BY THIS...ALTHOUGH COOLING WITHIN/AT THE TOP OF THE MIXED LAYER FROM
YESTERDAY WILL BE THE PRIMARY REASON FOR COOLER HIGHS. ONSHORE FLOW
WILL DEVELOP BY MID-MORNING WITH COOLER TEMPERATURES NEAR THE LAKE.
EXPECT THAT THE THERMAL DIFFERENCE BETWEEN DOWNTOWN CHICAGO AND FAR
WESTERN SUBURBS TO BE 10-12 DEGREES...NEAR THE LATE MAY CLIMO NORMAL
WITH ONSHORE FLOW ALL DAY.
TONIGHT THROUGH FRIDAY NIGHT...
A SURFACE HIGH WILL CENTER OVER THE AREA OFFERING LIGHT WIND FLOW.
BY LATE THIS EVENING AND THROUGH THIS PERIOD THERE LOOKS TO BE
LITTLE IN THE WAY OF CLOUDS. ONSHORE FLOW WILL REDEVELOP DURING
FRIDAY KEEPING LAKESIDE AREAS IN THE LOWER 60S OR SO. BOTH NIGHTS
LOOK TO SUPPORT 40S FOR LATE NIGHT LOWS IN THE MOST AREAS...WITH
SOME OF THE COOLER SPOTS REALIZING LOWER 40S ON FRIDAY NIGHT.
THE HOLIDAY WEEKEND INTO NEXT WEEK...
THE MEANDERING UPPER LOW ACROSS THE SOUTHWEST U.S. WILL DRIFT
NORTHEAST AS A RESULT OF BEING DISJOINTED FROM THE STRONGER WESTERLY
JET ACROSS THE U.S./CANADIAN BORDER. SUCH A CLOSED FEATURE IN THAT
PATTERN SEEMS TO MORE OFTEN THAN NOT MOVE SLOWER THAN INITIALLY
DEPICTED BY LONG RANGE GUIDANCE. WARM ADVECTION AND PRECIPITABLE
WATER INCREASE ARE FORECAST TO OCCUR SUNDAY AND MOST DETERMINISTIC
AND ENSEMBLE GUIDANCE HINT AT SOME CHANCE OF PRECIPITATION IN THE
REGION...THOUGH MAINLY NORTHWEST OF THE AREA. THE UPPER RIDGE IS
FORECAST TO RE-AMPLIFY OVER THE AREA ON THE HOLIDAY WITH A WEAK
SURFACE FRONT TO THE NORTH. IF THAT PATTERN WERE TO UNFOLD...THUNDER
CHANCES LOOK MINIMAL OVER THE FORECAST AREA. HAVE DECREASED THE
COVERAGE AND MAGNITUDE OF POPS PROVIDED BY A MODEL/PREVIOUS FORECAST
BLEND FOR THE HOLIDAY AND TUESDAY. THE UPPER LOW OR OPEN WAVE SHOULD
SHIFT EAST DURING THE MIDDLE OF THE WEEK...THOUGH THE 22.00 GFS
ACTUALLY TURNS THIS SOUTHEAST WITH BASICALLY VERY LITTLE PRECIP
CHANCES DURING MIDWEEK. WHILE THAT SEEMS A LITTLE SUSPECT...THE
CHANCES FOR RAIN LOOK SMALL AT THIS DISTANCE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* NORTHEAST WINDS WITH SUSTAINED SPEEDS LESS THAN 10 KT BY MID-
LATE MORNING VEERING MORE EASTERLY DURING AFTN.
* NORTHEAST WINDS FRIDAY.
KREIN
//DISCUSSION...UPDATED 12Z...
NO SIGNIFICANT AVIATION IMPACTS OVER THE NEXT 24 TO 30 HOURS UNDER
THE INFLUENCE OF DRY CANADIAN HIGH PRESSURE WITH VFR CONDITIONS
THROUGHOUT. LIGHT NORTHERLY WINDS EARLY THIS MORNING ARE EXPECTED
TO QUICKLY VEER NORTHEAST BY MID TO LATE MORNING AT ORD/MDW/GYY
WITH LAKE BREEZE PROBABLY MAKING IT TO DPA IN MID TO LATE
AFTERNOON. WINDS AT ORD/MDW/GYY ARE LIKELY TO VEER MORE TOWARD
EAST NORTHEAST OR EAST BY MID TO LATE AFTERNOON. SUSTAINED SPEEDS
AT ORD/MDW SHOULD AT LEAST OCCASIONALLY BE AROUND 10 KT FROM MID-
LATE AM THROUGH EARLY THIS EVENING. WINDS IN NORTH CENTRAL
ILLINOIS INCLUDING RFD WILL BACK FROM NORTHERLY TO NORTHWEST BY
MID DAY. LIGHT AND VARIABLE WINDS ARE EXPECTED AFTER SUNSET THIS
EVENING AS RIDGE AXIS MOVES OVERHEAD. LIGHT NORTH AND NORTHEAST
WINDS EARLY FRIDAY MORNING WILL LIKELY BECOME NORTHEAST AT ALL
TERMINALS AND INCREASE SOME BY MID TO LATE MORNING.
RC
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS.
* HIGH CONFIDENCE IN ALL OTHER ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. EARLY EVE NORTHEAST WINDS LIKELY BECOME LIGHT/VRB.
SATURDAY...VFR. EASTERLY WINDS THROUGH EVENING.
SUNDAY...SCHC TSRA...OTHERWISE MAINLY VFR.
MONDAY...CHC TSRA...OTHERWISE MAINLY VFR.
TUESDAY...SCHC TSRA...OTHERWISE MAINLY VFR. NE WIND SHIFT PSBL.
WEDNESDAY...CHC TSRA. NORTHEAST WINDS PSBL.
RC
&&
.MARINE...
301 AM CDT
EXPANSIVE HIGH PRESSURE SPREADING SOUTHEAST FROM THE UPPER MIDWEST
ACROSS THE GREAT LAKES REGION TODAY THROUGH SATURDAY WILL RESULT
IN AN EXTENDED PERIOD OF FAIRLY LIGHT WINDS AND LOW WAVES. WINDS
WILL INITIALLY BE NORTH AND NORTHWEST BUT TREND TOWARD GREATER
VARIABILITY LATER TODAY THROUGH SATURDAY AS THE HIGH BECOMES
PRIMARILY CENTERED OVER LAKE MICHIGAN. WINDS IN THE NEARSHORE
AREAS WILL BE CONTROLLED BY LAKE BREEZE INFLUENCES.
THE HIGH WILL THEN SLIDE EAST SUNDAY AND OFF THE ATLANTIC COAST ON
SUNDAY NIGHT...RESULTING IN INCREASING SOUTHERLY WINDS. AS BROAD
LOW PRESSURE OVER THE PLAINS AND CANADIAN PRAIRIES ON SUNDAY
CONSOLIDATES INTO A LOW CENTER NORTH OF THE LAKES ON
MONDAY...GUSTS COULD REACH UP TO 25 KT FOR A PERIOD LATE SUNDAY
INTO MONDAY DESPITE A VERY WARM AIR MASS MOVING OVER THE LAKE.
WITH THIS WARM AND MOIST AIR MASS WILL ALSO COME AN INCREASING
CHANCE FOR THUNDERSTORMS LATE SUNDAY THROUGH MONDAY EVENING.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
658 AM CDT Thu May 22 2014
.DISCUSSION...
ISSUED 319 AM CDT Thu May 22 2014
SHORT TERM...Today through Saturday
07z/2am surface analysis shows cold front extending from near
Paris to just south of Taylorville. Ahead of the boundary, a
warm/humid airmass persists across southeast Illinois where
dewpoints are in the middle to upper 60s. Meanwhile behind the
front, northerly winds have brought considerably drier air into
much of central Illinois, with dewpoints dropping into the upper
40s and lower 50s north of I-72. Front will continue to sag
southward today, eventually dropping south of the Ohio River by
late afternoon. As a result, cooler and less humid conditions can
be expected with high temps remaining in the 70s. Precip chances
will develop along/ahead of the front this afternoon, but will
remain south of the KILX CWA. The only potential fly in the
ointment will be a weak short-wave currently tracking out of
Colorado. As this feature approaches from the west, a few
showers/storms may spread into the far W/SW CWA this afternoon and
evening. While most models keep central Illinois completely dry
today and tonight, higher-res models such as the RAP and HRRR show
precip associated with the wave moving across central/southern
Iowa and approaching from the west this afternoon. Have therefore
included a slight chance POP along/southwest of a Rushville to
Jacksonville line this afternoon into tonight.
High pressure will build into the southern Great Lakes by the end
of the week, pushing the front even further south/southwest. With
dry N/NE flow around the high, sunny skies will be the rule on
both Friday and Saturday with temperatures in the 70s and low
relative humidity values.
LONG TERM...Sunday through Wednesday
As high slides off to the east, remnants of old frontal boundary
will return northward on Sunday. Models continue to produce some
QPF across the area as the warmer air returns: however, with only
meager forcing along a dissipating boundary and rising upper heights,
think this is overdone. Upper ridge will build in earnest across
the Midwest early next week, leading to temperatures climbing well
into the 80s. Big question will be how fast the ridge breaks down
as cut-off low currently over southern California works its way
eastward. GFS has been the slowest model with this process for the
past few runs and its 00z May 22 solution is no exception.
Meanwhile, ECMWF had previously been faster, but its latest run
has slowed down and now keeps wave west of Illinois until
Wednesday. Given high-amplitude upper ridge in place over the
Midwest, continue to favor a slower solution. Even though both the
GFS and ECMWF delay the arrival of the upper low until mid-week,
both produce QPF across the area on Monday and Tuesday. Given high
upper heights and lack of forcing, think little more than isolated
diurnal convection will fire on either of those two days. As such,
have kept the forecast dry until Wednesday when better forcing
arrives with the approaching upper low.
&&
.AVIATION...
ISSUED 655 AM CDT Thu May 22 2014
VFR conditions should prevail across the central IL airports
through 12Z/7 am Friday. Mid and high clouds to spread ese across
central IL during the day as ceilings lower to 7-12k ft. These
clouds will then scatter out from north to south during overnight
occurring near I-74 first. Isolated showers and thunderstorms
should stay sw of SPI this afteroon and evening. Thunderstorms
with MCS over nw MO, ne KS, se NE and sw IA and associated with a
short wave to track ese across northern MO and sw IL today and
evening along frontal boundary that has pushed south of I-70 early
this morning and will continue to stay south of central IL thru
tonight. NNW winds will be near 10 kts today and veer NNE tonight
and diminish to around 5 kts.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
352 AM CDT THU MAY 22 2014
.DISCUSSION...
306 AM CDT
A QUIET END TO THIS WEEK OFFERS MAINLY ONLY TEMPERATURE FORECAST
CHALLENGES. WHILE THERE ARE SMALL CHANCES OF THUNDERSTORMS FORECAST
FROM SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...THE REGIME FORECAST IS
ONE THAT KEEPS THE PROBABILITY LOW OF ANY HIGH IMPACT WEATHER THROUGH
THE HOLIDAY.
TODAY...
AN UPPER LOW ACROSS EASTERN ONTARIO THIS MORNING WILL CONTINUE TO
USHER A SURFACE COLD FRONT SOUTH FROM CENTRAL ILLINOIS AND INDIANA
TODAY. DAMPENED UPPER RIDGING WILL REMAIN IN PLACE FROM THE SOUTHERN
U.S. THROUGH THE MISSOURI RIVER VALLEY TODAY. WITH A STRONG UPPER
JET BETWEEN THESE TWO UPPER FEATURES...BROAD WEAK ASCENT WITHIN THE
RIGHT ENTRANCE REGION AND A SHEARED SHORT WAVE SHOULD SUPPORT HIGH
CLOUDS TO SPREAD ACROSS THE FORECAST AREA LATE THIS MORNING INTO THE
AFTERNOON. THIS IS LIKELY TO BE THICKER IN THE SOUTHERN FORECAST
AREA AND HAVE INCREASED FORECAST CLOUD COVER MORE SO THERE...BUT AT
LEAST SOME AREA WIDE. TEMPERATURES WILL LIKELY BE EFFECTED SLIGHTLY
BY THIS...ALTHOUGH COOLING WITHIN/AT THE TOP OF THE MIXED LAYER FROM
YESTERDAY WILL BE THE PRIMARY REASON FOR COOLER HIGHS. ONSHORE FLOW
WILL DEVELOP BY MID-MORNING WITH COOLER TEMPERATURES NEAR THE LAKE.
EXPECT THAT THE THERMAL DIFFERENCE BETWEEN DOWNTOWN CHICAGO AND FAR
WESTERN SUBURBS TO BE 10-12 DEGREES...NEAR THE LATE MAY CLIMO NORMAL
WITH ONSHORE FLOW ALL DAY.
TONIGHT THROUGH FRIDAY NIGHT...
A SURFACE HIGH WILL CENTER OVER THE AREA OFFERING LIGHT WIND FLOW.
BY LATE THIS EVENING AND THROUGH THIS PERIOD THERE LOOKS TO BE
LITTLE IN THE WAY OF CLOUDS. ONSHORE FLOW WILL REDEVELOP DURING
FRIDAY KEEPING LAKESIDE AREAS IN THE LOWER 60S OR SO. BOTH NIGHTS
LOOK TO SUPPORT 40S FOR LATE NIGHT LOWS IN THE MOST AREAS...WITH
SOME OF THE COOLER SPOTS REALIZING LOWER 40S ON FRIDAY NIGHT.
THE HOLIDAY WEEKEND INTO NEXT WEEK...
THE MEANDERING UPPER LOW ACROSS THE SOUTHWEST U.S. WILL DRIFT
NORTHEAST AS A RESULT OF BEING DISJOINTED FROM THE STRONGER WESTERLY
JET ACROSS THE U.S./CANADIAN BORDER. SUCH A CLOSED FEATURE IN THAT
PATTERN SEEMS TO MORE OFTEN THAN NOT MOVE SLOWER THAN INITIALLY
DEPICTED BY LONG RANGE GUIDANCE. WARM ADVECTION AND PRECIPITABLE
WATER INCREASE ARE FORECAST TO OCCUR SUNDAY AND MOST DETERMINISTIC
AND ENSEMBLE GUIDANCE HINT AT SOME CHANCE OF PRECIPITATION IN THE
REGION...THOUGH MAINLY NORTHWEST OF THE AREA. THE UPPER RIDGE IS
FORECAST TO RE-AMPLIFY OVER THE AREA ON THE HOLIDAY WITH A WEAK
SURFACE FRONT TO THE NORTH. IF THAT PATTERN WERE TO UNFOLD...THUNDER
CHANCES LOOK MINIMAL OVER THE FORECAST AREA. HAVE DECREASED THE
COVERAGE AND MAGNITUDE OF POPS PROVIDED BY A MODEL/PREVIOUS FORECAST
BLEND FOR THE HOLIDAY AND TUESDAY. THE UPPER LOW OR OPEN WAVE SHOULD
SHIFT EAST DURING THE MIDDLE OF THE WEEK...THOUGH THE 22.00 GFS
ACTUALLY TURNS THIS SOUTHEAST WITH BASICALLY VERY LITTLE PRECIP
CHANCES DURING MIDWEEK. WHILE THAT SEEMS A LITTLE SUSPECT...THE
CHANCES FOR RAIN LOOK SMALL AT THIS DISTANCE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* NORTHEAST WINDS BY MID MORNING VEERING MORE EASTERLY DURING
AFTN...WITH AT LEAST OCNL SUSTAINED SPEEDS AROUND 10 KT.
RC
//DISCUSSION...UPDATED 06Z...
NO SIGNIFICANT AVIATION IMPACTS OVER THE NEXT 24 TO 30 HOURS UNDER
THE INFLUENCE OF DRY CANADIAN HIGH PRESSURE WITH VFR CONDITIONS
THROUGHOUT. NORTHERLY WINDS ARE EXPECTED TO QUICKLY VEER
NORTHEAST BY MID TO LATE MORNING AT ORD/MDW/GYY WITH LAKE BREEZE
PROBABLY MAKING IT TO DPA IN MID TO LATE AFTERNOON. WINDS AT
ORD/MDW/GYY ARE LIKELY TO VEER MORE TOWARD EAST NORTHEAST OR EAST
BY MID TO LATE AFTERNOON. SUSTAINED SPEEDS AT ORD/MDW COULD AT
LEAST OCCASIONALLY BE AROUND 10 KT. WINDS IN NORTH CENTRAL
ILLINOIS INCLUDING RFD WILL BACK FROM NORTHERLY TO NORTHWEST BY MID
DAY. LIGHT AND VARIABLE WINDS ARE EXPECTED AFTER SUNSET THIS
EVENING AS RIDGE AXIS MOVES OVERHEAD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM-HIGH IN WIND TRENDS.
* HIGH IN REMAINING ELEMENTS.
RC
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY AND SATURDAY...VFR.
SUNDAY...SCHC TSRA OVERNIGHT WITH MVFR CIGS PSBL.
MONDAY...CHC TSRA...MVFR CIGS PSBL.
TUESDAY...SCHC TSRA...MVFR CIGS PSBL.
JEE
&&
.MARINE...
301 AM CDT
EXPANSIVE HIGH PRESSURE SPREADING SOUTHEAST FROM THE UPPER MIDWEST
ACROSS THE GREAT LAKES REGION TODAY THROUGH SATURDAY WILL RESULT
IN AN EXTENDED PERIOD OF FAIRLY LIGHT WINDS AND LOW WAVES. WINDS
WILL INITIALLY BE NORTH AND NORTHWEST BUT TREND TOWARD GREATER
VARIABILITY LATER TODAY THROUGH SATURDAY AS THE HIGH BECOMES
PRIMARILY CENTERED OVER LAKE MICHIGAN. WINDS IN THE NEARSHORE
AREAS WILL BE CONTROLLED BY LAKE BREEZE INFLUENCES.
THE HIGH WILL THEN SLIDE EAST SUNDAY AND OFF THE ATLANTIC COAST ON
SUNDAY NIGHT...RESULTING IN INCREASING SOUTHERLY WINDS. AS BROAD
LOW PRESSURE OVER THE PLAINS AND CANADIAN PRAIRIES ON SUNDAY
CONSOLIDATES INTO A LOW CENTER NORTH OF THE LAKES ON
MONDAY...GUSTS COULD REACH UP TO 25 KT FOR A PERIOD LATE SUNDAY
INTO MONDAY DESPITE A VERY WARM AIR MASS MOVING OVER THE LAKE.
WITH THIS WARM AND MOIST AIR MASS WILL ALSO COME AN INCREASING
CHANCE FOR THUNDERSTORMS LATE SUNDAY THROUGH MONDAY EVENING.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
319 AM CDT Thu May 22 2014
.DISCUSSION...
ISSUED 319 AM CDT Thu May 22 2014
SHORT TERM...Today through Saturday
07z/2am surface analysis shows cold front extending from near
Paris to just south of Taylorville. Ahead of the boundary, a
warm/humid airmass persists across southeast Illinois where
dewpoints are in the middle to upper 60s. Meanwhile behind the
front, northerly winds have brought considerably drier air into
much of central Illinois, with dewpoints dropping into the upper
40s and lower 50s north of I-72. Front will continue to sag
southward today, eventually dropping south of the Ohio River by
late afternoon. As a result, cooler and less humid conditions can
be expected with high temps remaining in the 70s. Precip chances
will develop along/ahead of the front this afternoon, but will
remain south of the KILX CWA. The only potential fly in the
ointment will be a weak short-wave currently tracking out of
Colorado. As this feature approaches from the west, a few
showers/storms may spread into the far W/SW CWA this afternoon and
evening. While most models keep central Illinois completely dry
today and tonight, higher-res models such as the RAP and HRRR show
precip associated with the wave moving across central/southern
Iowa and approaching from the west this afternoon. Have therefore
included a slight chance POP along/southwest of a Rushville to
Jacksonville line this afternoon into tonight.
High pressure will build into the southern Great Lakes by the end
of the week, pushing the front even further south/southwest. With
dry N/NE flow around the high, sunny skies will be the rule on
both Friday and Saturday with temperatures in the 70s and low
relative humidity values.
LONG TERM...Sunday through Wednesday
As high slides off to the east, remnants of old frontal boundary
will return northward on Sunday. Models continue to produce some
QPF across the area as the warmer air returns: however, with only
meager forcing along a dissipating boundary and rising upper heights,
think this is overdone. Upper ridge will build in earnest across
the Midwest early next week, leading to temperatures climbing well
into the 80s. Big question will be how fast the ridge breaks down
as cut-off low currently over southern California works its way
eastward. GFS has been the slowest model with this process for the
past few runs and its 00z May 22 solution is no exception.
Meanwhile, ECMWF had previously been faster, but its latest run
has slowed down and now keeps wave west of Illinois until
Wednesday. Given high-amplitude upper ridge in place over the
Midwest, continue to favor a slower solution. Even though both the
GFS and ECMWF delay the arrival of the upper low until mid-week,
both produce QPF across the area on Monday and Tuesday. Given high
upper heights and lack of forcing, think little more than isolated
diurnal convection will fire on either of those two days. As such,
have kept the forecast dry until Wednesday when better forcing
arrives with the approaching upper low.
Barnes
&&
.AVIATION...
ISSUED 1210 AM CDT Thu May 22 2014
Strong to severe thunderstorms have shifted se of central IL TAF
sites by late evening with thunderstorms currently moving ese
toward I-70 in southeast IL. Cold front is just pushing south of
I-72 by midnight and will continue to slowly push southward into
southeast IL overnight keeping isolated to scattered thunderstorms
south of central IL rest of tonight. Any redevelopment of isolated
showers and thunderstorms should stay sw of SPI Thu and will keep
all 5 central IL TAFs dry next 24 hours. Could be some MVFR fog
restrictions at CMI later tonight which received 3.61 inches of
rain during late afternoon and evening hours. Patches of mid level
clouds from 6-12k ft over central IL with broken ceilings possible
next few hours. WSW winds at DEC and CMI should veer NNW next hour
or two as cold frontal zone slips south of these airports. Wind
speeds fairly light through Thu from 5-10 kts.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1231 AM CDT THU MAY 22 2014
.DISCUSSION...
350 PM CDT
MAIN FORECAST CONCERNS ARE WITH STRONG TO SEVERE THUNDERSTORMS IN
THE NEAR TERM...AS WELL AS TEMP TRENDS INTO THE EVENING.
LATEST RADAR IMAGERY DEPICTING RAPID THUNDERSTORM DEVELOPMENT IN
AND AROUND SURFACE TROUGH/COLD FRONT ACROSS EAST CENTRAL ILLINOIS
AND NORTH CENTRAL INDIANA. OUT AHEAD OF THIS FRONT...DEWPOINTS IN
THE MID/UPPER 60S STILL RESIDE AND ARE AIDING IN MODERATE TO
STRONG INSTABILITY. INCREASING SHEAR AND STEEP LOW/MID LEVEL LAPSE
RATES ARE PROVIDING FOR SOME RATHER ROBUST DEVELOPMENT ACROSS THIS
GENERAL AREA...CLIPPING THE FAR SOUTHERN TIER OF COUNTIES...WITH
LARGE HAIL THE PRIMARY THREAT. EXPECT THIS DEVELOPMENT TO REMAIN
CONFINED TO THE CURRENT LOCATION AND SOUTHWARD OVER THE NEXT ONE
TO TWO HOURS...BEFORE THESE THUNDERSTORMS SHIFT SOUTH WITH THE
SOUTHWARD MOVEMENT TO THE FRONT. DONT ANTICIPATE ANY FURTHER
DEVELOPMENT THIS EVENING OVERNIGHT...WITH DRY CONDITIONS EXPECTED
FOR THE CWA OVERNIGHT. TEMPS ARE CURRENTLY STILL WARMING PRETTY
GOOD WITH MID/UPPER 80S OVERHEAD WITH THE EXCEPTION OF COOLER
CONDITIONS NEAR THE LAKE. AS STRONGER PRESSURE GRADIENT TO THE
NORTHWEST CONTINUES TO SHIFT EAST WITH TIME HERE IN THE NEXT
COUPLE OF HOURS...FEEL THAT A SHIFT TO THE NORTHWEST WILL STILL BE
ABLE TO HELP THE LAKE BREEZE TO RETREAT LATE THIS AFTERNOON AND
EVENING AND WITH SOME WARMING STILL POSSIBLE NEAR THE LAKE.
ONGOING COLD ADVECTION WILL CONTINUE OVERNIGHT...AND WITH CLEARING
SKIES AND MUCH DRIER AIR IN PLACE...A COOLER NIGHT IN THE 50S WILL
BE LIKELY.
RATHER QUIET CONDITIONS EXPECTED OVER THE NEXT SEVERAL DAYS AND
EVEN INTO THE WEEKEND...WITH DRY CONDITIONS LIKELY. WEAK COLD
ADVECTION WILL CONTINUE OVER THE NEXT COUPLE OF DAYS WITH COOLER
TEMPERATURES IN THE 70S/60S EXPECTED. BUILDING HIGH PRESSURE FROM
THE NORTHWEST WILL ESTABLISH ITSELF OVERHEAD BY THE END OF THE
WORK WEEK BEFORE SHIFTING TO THE EAST THROUGH THE WEEKEND. THIS
WILL OCCUR AS UPPER LEVEL RIDGING OCCURS ACROSS THE REGION...AND
WHILE WAA BRINGS A RETURN TO WARMER WEATHER. ALTHOUGH WARMER
WEATHER IS EXPECTED NEXT WEEK...IT DOES LOOK UNSETTLED WITH
SHOWER/THUNDERSTORM CHANCES WITH THE RETURN OF A MORE MOIST
ENVIRONMENT.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NORTHEAST WINDS BY MID MORNING VEERING MORE EASTERLY DURING AFTN.
RC
//DISCUSSION...UPDATED 06Z...
NO SIGNIFICANT AVIATION IMPACTS OVER THE NEXT 24 TO 30 HOURS UNDER
THE INFLUENCE OF DRY CANADIAN HIGH PRESSURE WITH VFR CONDITIONS
THROUGHOUT. NORTHERLY WINDS ARE EXPECTED TO QUICKLY VEER
NORTHEAST BY MID TO LATE MORNING AT ORD/MDW/GYY WITH LAKE BREEZE
PROBABLY MAKING IT TO DPA IN MID TO LATE AFTERNOON. WINDS AT
ORD/MDW/GYY ARE LIKELY TO VEER MORE TOWARD EAST NORTHEAST OR EAST
BY MID TO LATE AFTERNOON. SUSTAINED SPEEDS AT ORD/MDW COULD AT
LEAST OCCASIONALLY BE AROUND 10 KT. WINDS IN NORTH CENTRAL
ILLINOIS INCLUDING RFD WILL BACK FROM NORTHERLY TO NORTHWEST BY MID
DAY. LIGHT AND VARIABLE WINDS ARE EXPECTED THIS AFTER SUNSET THIS
EVENING AS RIDGE AXIS MOVES OVERHEAD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH IN WIND TRENDS.
RC
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY AND SATURDAY...VFR.
SUNDAY...SCHC TSRA OVERNIGHT WITH MVFR CIGS PSBL.
MONDAY...CHC TSRA...MVFR CIGS PSBL.
TUESDAY...SCHC TSRA...MVFR CIGS PSBL.
JEE
&&
.MARINE...
202 PM CDT
A FAIRLY BROAD AREA OF LOW PRESSURE IS POSITIONED OVER THE WESTERN
GREAT LAKES AND WILL MOVE EASTWARD TONIGHT AND THURSDAY. A COLD
FRONTAL BOUNDARY WILL MOVE ACROSS THE LAKE THIS EVENING WHICH WILL
BRING A STEADIER NORTHWEST WIND AS WELL AS DRIER AIR...WHICH WILL
WORK TO ERODE THE REMAINING FOG ACROSS THE OPEN WATERS LATE THIS
AFTERNOON AND EARLY THIS EVENING. GENERALLY LIGHT NORTHERLY FLOW
WILL REMAIN ACROSS THE LAKE INTO THE WEEKEND AS HIGH PRESSURE MOVES
OVER LAKE MICHIGAN. A SHIFT TO ONSHORE WINDS IS LIKELY THURSDAY AND
FRIDAY...WITH MORE VARIABILITY SATURDAY AS THE HIGH MOVES OVERHEAD.
A SHIFT TO A STEADIER SOUTHERLY WIND IS EXPECTED SATURDAY NIGHT AS
THE HIGH MOVES OFF TO THE EAST. LOW PRESSURE IS FORECAST TO TRACK
NORTHEAST ACROSS THE UPPER MIDWEST SUNDAY NIGHT AND MONDAY WHICH
WILL TIGHTEN THE PRESSURE GRADIENT LEADING TO A BIT OF AN INCREASE
IN WIND SPEEDS BUT STABLE AIR OVER THE LAKE SHOULD KEEP GUST
FREQUENCY LOW.
MDB
&&
.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
1213 AM CDT Thu May 22 2014
.DISCUSSION...
ISSUED 842 PM CDT Wed May 21 2014
The cold front appears to be finally making some progress
southward toward Lincoln, but it is still slow. Conditions are
setting up for an E-W line of storms to fill in ahead of the cold
front, as a shortwave moves northeast along the front. NW flow
aloft will work in conjunction with the low level dynamics to cause
some back-building of the storms to the west. Instability params
look favorable for continued strong to severe thunderstorm
development through at least 10 pm, then we should see some
stabilization of the boundary layer helping to reduce the hail
threat and shift the focus to more heavy rain from training
storms.
The latest severe thunderstorm watch is in affect until 2 am, but
hopefully we can clear most of that watch before midnight. We kept
high chance PoPs across the southern half of our forecast area,
with low chance toward Havana to Bloomington.
After midnight, precip chances should be confined to our far
southern counties as the front approaches the I-70 corridor. Some
clearing in our NW counties late tonight may allow for cooler lows
in the mid 50s, which the forecast handled well already.
The evening updates have been tied to watch issuances and
adjustments, and the latest forecast data are already available.
&&
.AVIATION...
ISSUED 1210 AM CDT Thu May 22 2014
Strong to severe thunderstorms have shifted se of central IL TAF
sites by late evening with thunderstorms currently moving ese
toward I-70 in southeast IL. Cold front is just pushing south of
I-72 by midnight and will continue to slowly push southward into
southeast IL overnight keeping isolated to scattered thunderstorms
south of central IL rest of tonight. Any redevelopment of isolated
showers and thunderstorms should stay sw of SPI Thu and will keep
all 5 central IL TAFs dry next 24 hours. Could be some MVFR fog
restrictions at CMI later tonight which received 3.61 inches of
rain during late afternoon and evening hours. Patches of mid level
clouds from 6-12k ft over central IL with broken ceilings possible
next few hours. WSW winds at DEC and CMI should veer NNW next hour
or two as cold frontal zone slips south of these airports. Wind
speeds fairly light through Thu from 5-10 kts.
07
&&
.PREV DISCUSSION...
ISSUED 158 PM CDT Wed May 21 2014
Severe storm potential will highlight the short term. A brief period
of cooler temps will close out the week, before a long wave ridge
builds into our area for the weekend. As that ridge slides east
later this weekend, a few late afternoon thunderstorms could bubble
up in our western areas on Sunday and Memorial Day as moisture
and heat return to IL.
SHORT TERM...Tonight through Saturday.
The initial severe thunderstorm watch #164 does not include any of
IL, but we still expect some thunderstorms to develop along the
cold front in IL later this afternoon. At 18z/1 pm, the front
extended on a line through Bloomington and Rushville. Surface
dewpoints ahead of the front had climbed into the mid 60s, with
air temps in the mid to upper 80s. Surface based CAPEs were in the
2800-3300 J/kg, with 0-6km wind shear of 35-50kts. LAPS soundings
were indicating little to no cap above the LCL. We should see some
of the storms become strong in our area, with very large hail the
main hazard and damaging winds possible. Supercell formation
appears likely at the onset, with the better chances of linear
progression most likely occurring after the storms advance eastward
into Indiana. The cumulus field on across C IL appears to be
deepening, with some towering cu. A watch may be needed in IL in
the 2-3 pm time frame.
Will maintain high chance PoPs the rest of the afternoon and into
the evening, as coverage could be limited by breaks in the line of
storm cells that develop.
The latest 4km model HRRR output shows rather limited coverage of
storms on an E-W line along and south of I-72, with storms
generally south of our CWA by 06z/1am. Will keep PoPs after
midnight limited to the far southern areas.
The cold front forward progress will slow down and stall near the
southern tip of IL, keeping shower and storm chances close by to
the south and west of our forecast area. We held onto a narrow
area of slight chance PoPs along our far southern counties on
Thurs and Thur night as a result.
Surface high pressure and a building ridge aloft should help keep
our area rain free on Friday and Saturday as moisture return will
be primarily into the Missouri and areas west.
A brief cooler period will occur from Thursday into Friday behind
today`s cold front. Highs will still linger right around normal in
the mid to upper 70s. Saturday will see temps begin a warming
trend, but highs will still remain mainly in the upper 70s.
LONG TERM...Sunday through Wednesday.
Warming through a deeper layer will develop on Sunday as the
surface ridge axis slides east of Illinois and southerly return
flow increases. Low and mid level moisture content will increase as
well, with dewpoints returning to the 60s west of I-55 on Sunday.
Thunderstorm chances will be mainly west of our forecast area, in
the vicinity of a surface trough along the Mississippi river
valley. Instability params support storm progression into western
IL, so we went with low chance and slight chance PoPs west of
I-55. A weakening of the surface trough and increasing cap
strength on Memorial Day may help to diminish storm chances a
little. However, an weak disturbance in the 400-600 mb layer
could cause a few isolated storms. We went with slight chance PoPs
NW of a line from Springfield to Champaign, for mainly late
afternoon/early evening storm potential. Most areas should remain
dry though. Memorial Day looks to be the warmest day of the
holiday weekend, as highs return to the mid 80s. Dewpoints in the
low to mid 60s will make it feel a bit humid outside as well.
On Tuesday and Wednesday, the ECMWF, and to some extent the GFS,
progress an upper low into the ridge, triggering a wider coverage
of showers and storms. Low chance PoPs were included for all our
counties Tuesday and Wednesday to account for the relative
agreement on a wetter solution. Increasing clouds and rain
potential should keep high temps in the 70s both days.
Shimon
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
336 AM CDT THU MAY 22 2014
.SHORT TERM /TODAY/...
ISSUED AT 336 AM CDT THU MAY 22 2014
COMPLEX OF STORMS MOVING THROUGH SOUTHEAST NEBRASKA AND NORTHERN
KANSAS EARLY THIS MORNING. SFC HIGH PRESSURE IS RIDGED THROUGH THE
NORTHERN PLAINS EARLY THIS MORNING AND IS EXPECTED TO SHIFT SOUTH
THROUGH THE DAY WITH DRIER MID LEVEL AIR ARRIVING FROM THE NORTH.
THE PRIMARY CHALLENGE TODAY IS PRECIPITATION CHANCES AND
TEMPERATURES OVER THE SOUTH WHERE CLOUD COVER WILL HAVE AN IMPACT.
THE PRECIPITATION SHOULD REACH THE FAR SOUTHWEST AS THE 850 MB
BOUNDARY LIFTS INTO THAT REGION. SOME KINEMATIC FORCING WILL
OVERRIDE THIS BOUNDARY AND WILL PROVIDE ENOUGH FORCING TO KEEP THE
COMPLEX INTACT IN AT LEAST SOME FORM. THE COMPLEX SHOULD DIMINISH IN
INTENSITY AS IT SHIFTS EAST THROUGH THE MORNING AS A MORE STABLE
AIRMASS WILL BE IN PLACE OVER SOUTHEAST IOWA. HAVE REMAINED
CONSERVATIVE ON POPS AT THIS TIME THOUGH SUSPECT THIS MAY BE TOO LOW
OVER PORTIONS OF THE SOUTH WITH THE INFLUENCE OF THE HIGH PRESSURE
NOT ARRIVING UNTIL LATER IN THE PERIOD. WARMEST TEMPERATURES TODAY
ARE EXPECTED OVER THE NORTH WHERE THE BEST POTENTIAL FOR SUNSHINE
EXISTS.
.LONG TERM /TONIGHT THROUGH TUESDAY/...
ISSUED AT 336 AM CDT THU MAY 22 2014
LITTLE HAS CHANGED IN FORECAST THINKING FROM PREVIOUS SHIFTS. COOL
AND DRY WEATHER WILL PREVAIL FROM TONIGHT INTO SATURDAY AS A
SURFACE HIGH PRESSURE AREA DOMINATES THE REGION. DURING THE DAY ON
SATURDAY A 500 MB RIDGE AXIS WILL MOVE OVERHEAD AND THE SURFACE
HIGH WILL BEGIN TO MOVE OFF TO THE EAST...BRINGING A RETURN OF
SOUTH SOUTHEAST SURFACE FLOW AND INCREASED MOISTURE ALONG WITH
BROAD BUT WEAK ASCENT ALOFT. THIS SHOULD RESULT IN SOME SHOWERS
AND THUNDERSTORMS MOVING ACROSS THE FORECAST AREA IN A WARM AIR
ADVECTION REGIME BETWEEN SATURDAY AFTERNOON AND SUNDAY EVENING.
WHILE THERE REMAIN DISCREPANCIES IN THE COVERAGE AND TIMING OF
PRECIP...ESPECIALLY WITH A LARGE DRY AIRMASS IN PLACE AHEAD OF
IT...CONFIDENCE IS HIGH IN AT LEAST SCATTERED SHOWERS AND STORMS
AROUND SATURDAY NIGHT AND HAVE INCLUDED 40 TO 60 POPS ACROSS MOST
OF THE AREA TO ACCOUNT FOR THIS.
FROM SUNDAY NIGHT INTO MONDAY 500 MB RIDGING WILL BUILD IN ONCE
AGAIN AND SHOULD PROVIDE A BREAK FROM RAIN ALONG WITH A LITTLE
WARMING...HOWEVER DURING THIS TIME A LARGE 500 MB CUTOFF LOW WILL
BE MOVING FROM THE SOUTHERN INTO THE CENTRAL HIGH PLAINS. THIS LOW
WILL SUBSEQUENTLY STALL OVER KANSAS/MISSOURI/OKLAHOMA/ARKANSAS FOR
MULTIPLE DAYS THROUGH THE MIDDLE OF NEXT WEEK. THIS TRANSLATES TO
A LOT OF 20 TO 40 POPS AS IT IS DIFFICULT TO PIN DOWN ANY GIVEN
FORECAST TIME PERIOD AS BEING PARTICULARLY DRY OR WET...ALTHOUGH
GENERALLY THE BEST RAIN CHANCES SHOULD BE BETWEEN LATE MONDAY AND
LATE TUESDAY WHEN THE 500 MB LOW FIRST APPROACHES. OVERALL WE ARE
LOOKING AT A SOMEWHAT ACTIVE BUT BENIGN EARLY SUMMER PATTERN FOR
MOST OF THE LONG TERM FORECAST...CHARACTERIZED BY MODERATE
TEMPERATURES...INTERMITTENT RAIN CHANCES...AND NO REALLY
SIGNIFICANT STORM SYSTEMS WITH LITTLE THREAT OF SEVERE WEATHER.
&&
.AVIATION...22/06Z
ISSUED AT 1134 PM CDT WED MAY 21 2014
A FEW MINOR CHANGES FROM PREVIOUS PACKAGE. CONVECTION OVER
COLORADO/NEBRASKA EXPECTED TO HOLD TOGETHER AND RIDE ALONG H850
FRONTAL BOUNDARY FROM NORTHERN KS TO NORTHERN MO THROUGH THE
OVERNIGHT HOURS. CURRENT HRRR AND NOW THE 00Z GFS LIFTS THE
WEAKENING AREA OF CONVECTION INTO SW IOWA BY 10Z AND IT DRIFTS
NORTHEAST TOWARD KDSM BY 14Z PRIOR TO WEAKENING THROUGH 18Z. HAVE
INCLUDED VCSH AT 14Z. CONSIDERING MUCAPE IS LESSENING TOWARD
MORNING AS LEFTOVER CONVECTION ENCOUNTERS WEAK MID LEVEL BUBBLE
HIGH OVER IOWA...ANY THUNDER SHOULD BE CONFINED TO THE SOUTHWEST.
OTHERWISE...EARLIER THINKING HOLDS WITH HIGH DRIFTING SOUTH
THROUGH THE DAY AND CLOUDS THINNING TOWARD 00Z./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...LEE
AVIATION...REV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1134 PM CDT WED MAY 21 2014
.SYNOPSIS...
ISSUED AT 311 PM CDT WED MAY 21 2014
COLD FRONT JUST SOUTH OF IA WILL CONTINUE TO SINK SLOWLY SOUTH AS
HIGH PRESSURE FROM MANITOBA INTO NEBRASKA PUSHES SOUTHWARD. HIGH
WILL SLIDE SOUTH AND EAST VERY SLOWLY AND WILL BE THE DOMINANT
FEATURE THROUGH THE REST OF THE WORK WEEK. AS IS SLIDES OFF
SAT...THE UPPER LOW IN THE SRN BRANCH OF THE WESTERLIES WILL MOVE
INTO THE CENTRAL U.S. FOR THE SAT-TUE TIME FRAME.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 311 PM CDT WED MAY 21 2014
BENIGN WEATHER IS FORECAST TONIGHT AS A SURFACE HIGH BUILDS INTO
IOWA WITH A NORTHWEST FLOW ALOFT. THE HIGH WILL BRING IN DRIER AIR
TO CENTRAL IOWA. CURRENT OBS HAVE MID 40 DEWPOINTS INTO NW IOWA AND
THAT DRIER AIR WILL WORK ACROSS THE FORECAST AREA TONIGHT. WE WILL
LIKELY NOT SEE MID 40S ACROSS THE SOUTH BUT UPPER 40S TO AROUND 50
ARE LIKELY. THE FRONTAL BOUNDARY THAT MOVED THROUGH LAST NIGHT AND
THIS MORNING WILL STALL OUT AND RESIDE JUST TO THE SOUTH OF IOWA.
VERY WARM MOIST AND UNSTABLE AIR WILL REMAIN JUST TO THE SOUTH OF
IOWA AS A RESULT SO THERE MAY BE SOME CU DEVELOPMENT THROUGH LATE
AFTERNOON BUT BY AND LARGE THE HIGH AND THE DRIER AIR WILL WIN OUT
KEEPING A CLEAR TO MOSTLY CLEAR SKY IN PLACE ALONG WITH COOL TEMPS.
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 311 PM CDT WED MAY 21 2014
HIGH PRESSURE WILL KEEP THE PRECIPITATION TO THE SOUTH AND WEST OF
THE CWA WITH A DRY EASTERLY FLOW THROUGH FRIDAY NIGHT. AS HIGH
MOVES OFF TO THE EAST THE SHOWERS AND THUNDERSTORMS WILL
SPREAD EAST SLOWLY WITH RAIN OVER THE ENTIRE AREA BY SUNDAY NIGHT.
UNSETTLED WEATHER WILL CONTINUE THROUGH TUE AS THE UPPER LOW
ADVANCES INTO THE CENTRAL U.S. TEMPS CLOSE TO MOS VALUES...A
LITTLE LOWER EARLY NEXT WEEK DUE TO THE CLOUDS AND RAINFALL.
&&
.AVIATION...22/06Z
ISSUED AT 1134 PM CDT WED MAY 21 2014
A FEW MINOR CHANGES FROM PREVIOUS PACKAGE. CONVECTION OVER
COLORADO/NEBRASKA EXPECTED TO HOLD TOGETHER AND RIDE ALONG H850
FRONTAL BOUNDARY FROM NORTHERN KS TO NORTHERN MO THROUGH THE
OVERNIGHT HOURS. CURRENT HRRR AND NOW THE 00Z GFS LIFTS THE
WEAKENING AREA OF CONVECTION INTO SW IOWA BY 10Z AND IT DRIFTS
NORTHEAST TOWARD KDSM BY 14Z PRIOR TO WEAKENING THROUGH 18Z. HAVE
INCLUDED VCSH AT 14Z. CONSIDERING MUCAPE IS LESSENING TOWARD
MORNING AS LEFTOVER CONVECTION ENCOUNTERS WEAK MID LEVEL BUBBLE
HIGH OVER IOWA...ANY THUNDER SHOULD BE CONFINED TO THE SOUTHWEST.
OTHERWISE...EARLIER THINKING HOLDS WITH HIGH DRIFTING SOUTH
THROUGH THE DAY AND CLOUDS THINNING TOWARD 00Z./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MS MAY 14
SHORT TERM...FAB
LONG TERM...MS MAY 14
AVIATION...REV
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
557 PM CDT Thu May 22 2014
...Updated for the aviation discussion...
.SHORT TERM...(This evening through Friday)
ISSUED AT 346 PM CDT THU MAY 22 2014
Tonight:
Main concern is dealing with orographic convection to the west. Afternoon
radar mosaic shows considerable thunderstorm activity across Colorado
and New Mexico. MCS propagation vectors support the eastward translation
of this activity and will eventually reach far SW Kansas by evening.
The HRRR is insistent in generating an MCS with a cold pool. This model
does seem to be - at times- too aggressive with cold pool generation.
Still, enough isentropic lift and moisture advection supports ramping
up the pops this evening. Think the main concern is heavy rainfall as
the 12Z KDDC raob PWAT is between the 75th percentile and the +2SD mark.
This is statistically significant. Bulk shear is far from reaching supercell
archetype. Secondary threat to heavy rainfall is outflow winds, which
could impact far western Kansas along and west of Highway 83. The boundary
layer will become more stable this evening, so that could mitigate any
momentum transfer issues. In addition to convection, have increased
QPF more in line with WPC guidance. Most of the mesoscale models (HRRR/WRF/4
km NAM) all suggest that a good chunk of the region might see 0.50-1.00"
from tonights and tomorrow thunderstorm activity.
Tomorrow:
Have ramped up pops again by afternoon and evening as PWAT remains near
an 1.00" and isentropic lift/warm air advection continues through the
day. Moist adiabatic thermodynamic skew-t/log-p`s and also slow MCS
propagation vectors suggest that heavy rainfall is still a threat for
tomorrow. Highest pops will be during the afternoon to 00Z as diurnally
induced instability increases. Again, would not be surprised to see
decent rainfall amounts through 7 pm tomorrow night, as alluded to
above.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 235 PM CDT THU MAY 22 2014
Medium range models indicate a southwest flow aloft prevailing
across the Western High Plains Saturday as a closed off upper level
low shifts slowly eastward across the Four Corners Region. As the
system approaches, increased divergence aloft downstream of the
trough axis will intensify across the high plains of eastern
Colorado, western Kansas, and the panhandle of Oklahoma, especially
into Saturday evening. Meanwhile, a prevailing low level
south-southeasterly flow will continue to draw additional moisture
into the state with H85 dewpoints nearing 15C. Although the flow
aloft is expected to remain generally weak, GFS/ECMWF model
soundings do show some marginal directional shear along with SBCAPE
values in excess of 1500 J/KG. As H5 vort maxima cycle northeast out
of the trough axis into the high plains, shower and thunderstorm
development is likely with some chance for marginally severe
weather possible. However, a bigger concern may be the potential
for brief periods of heavy rainfall with model soundings also
showing PW values well over one inch.
Similar conditions will exist Sunday as the closed off upper level
low moves across the Rockies into the Western High Plains. However,
a few more thunderstorms may be possible as an upper level jet noses
northward into southwest Kansas Sunday afternoon while a developing
dryline sharpens near the Colorado border. In addition, GFS/ECMWF
model soundings indicate an inverted V profile by Sunday afternoon
with SBCAPE values pushing above 2000 J/KG. Although speed shear
looks a little more favorable than Saturday, directional shear
does not which may limit the strength of any developing storms.
However, the potential for significant rainfall lingers with PW
values remaining fairly high with values near to a little above
one inch. Shower and thunderstorm potential shifts eastward more
into central Kansas Monday as the closed off low pushes further
east into western Kansas. Drier conditions are likely by Wednesday
as weak upper level ridging fills in across the Western High
Plains in wake of the departing upper level low.
Fairly mild temperatures are likely Saturday as a cooler air mass
remains locked in across the Western High Plains The GFS/ECMWF show
H85 temperatures changing little from Friday with the mid teens(C)
across central Kansas to the upper teens(C) out near the Colorado
border. Due to expected increased cloud cover and areas of precip,
look for highs up into the upper 70s(F) to near 80F. Similar
temperatures are likely into Monday before a gradual warming
trend begins by mid week as weak upper level ridging develops
across the Intermountain West.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 552 PM CDT THU MAY 22 2014
There is a large upper level wave moving east through southwestern
Kansas. This will being thunderstorms first to GCK by 02Z, DDC by
04Z and not to HYS until 08-09Z. Cigs with the thunderstorm
passage will be MVFR in the OVC040 range, but winds may gust near
the thunderstorms in the 20g35kt range. The convection will pass
and VFR conditions will return towards 10 to 11Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 79 61 80 / 70 60 60 60
GCK 61 78 60 81 / 70 60 60 60
EHA 59 76 59 80 / 70 40 50 60
LBL 61 76 61 81 / 70 60 60 60
HYS 62 78 62 80 / 40 60 60 50
P28 66 80 64 82 / 40 60 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...JJohnson
AVIATION...Burke
AREA FORECAST DISCUSSION
NWS GOODLAND KS
328 PM MDT THU MAY 22 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 148 PM MDT THU MAY 22 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS LARGE CLOSED UPPER OVER
SOUTHERN CALIFORNIA WITH RIDGE ACROSS PLAINS AND SOUTHEASTERN US.
SOUTHERLY/DIFLUENT FLOW IS IN PLACE ACROSS THE SOUTHERN PLAINS AND
ROCKIES WITH MOIST PLUME EXTENDING FROM PACIFIC NORTH WITHIN THIS
FLOW. AT THE SURFACE A STALLED FRONT IS ANALYZED ACROSS SOUTHERN KS
AND ACROSS OK/TX PANHANDLES. UPSTREAM RADARS SHOW THUNDERSTORM
ACTIVITY ALREADY DEVELOPING ACROSS NORTHEAST NEW MEXICO AND ALONG
THE FRONT RANG WITH A NORTHERLY PROGRESSION.
UPPER LEVEL ENERGY ROTATING THROUGH THE UPPER FLOW ON THE EASTERN
EDGE OF THE UPPER TROUGH WE WILL CONTINUE TO SUPPORT
SHOWER/THUNDERSTORM DEVELOPMENT. ANOMALOUSLY MOIST AIR MASS (PWATS
TWO STANDARD DEVIATIONS ABOVE NORMAL) WILL LINGER TONIGHT THROUGH
TOMORROW.
FOR TONIGHT...THUNDERSTORMS ARE DEVELOPING IN PROXIMITY TO LARGE
SCALE DIFLUENT FLOW OVER NEW MEXICO AND CENTRAL COLORADO. TD VALUES
AROUND 60F HAS LEAD TO SBCAPE 1500-2000 J/KG. GUIDANCE SHOWS MUCAPE
THROUGH FRIDAY AROUND 2000 J/KG OVER OUR CWA. GUIDANCE SUPPORTS
THUNDERSTORM ACTIVITY UPSTREAM FROM OUR CWA MERGING INTO
CLUSTER/THUNDERSTORM COMPLEX AND SPREADING NORTH INTO OUR CWA. WITH
ELEVATED FRONTAL ZONE GENERALLY LINGERING NEAR THE I-70 CORRIDOR AND
MOISTURE POOLING/INSTABILITY LINGERING WE SHOULD SEE A GOOD PATTERN
FOR THIS ACTIVITY INCREASING IN COVERAGE. 0-6KM WIND IS 15KT OR
LESS...HOWEVER WIND PROFILES BELOW 800MB ARE VERY WEAK ALONG FRONTAL
ZONE OUT OF THE EAST...WHILE 400-250MB WINDS ARE STRAIGHT OUT OF THE
WEST. IN ADDITION TO THE ALREADY WET SIGNAL THIS PATTERN SUPPORTS
BACK BUILDING OF THUNDERSTORMS ALONG FRONTAL ZONE AND VERY SLOW
PROPAGATION OF THUNDERSTORMS. CONFIDENCE IS INCREASING IN AT LEAST A
LOCALIZED FLOODING THREAT TONIGHT...BUT I AM NOT SURE HOW WIDESPREAD
THIS WILL BE SO I AM HOLDING OFF ON ISSUANCE OF FLASH FLOOD WATCH.
SHEER PROFILES ARE NOT THAT IMPRESSIVE...HOWEVER WITH MODERATE
INSTABILITY/GOOD MID LEVEL LAPSE RATES...DAMAGING WINDS ASSOCIATED
WITH COLD POOL DRIVEN THUNDERSTORM COMPLEXES OR STRONG WIND/LARGE
HAIL WITH PULSE TYPE CONVECTION CANT BE RULED OUT.
GUIDANCE SHOWS GOOD 850MB SUPPORT LINGERING OVERNIGHT AND MODELS
CONTINUE TO LINGER SHOWERS/THUNDERSTORMS THROUGH TOMORROW
AFTERNOON...WITH AN ENHANCEMENT IN ACTIVITY AS SURFACE FRONT STALLS
ALONG KS/NE STATE LINE. I WAS COMFORTABLE LINGERING POPS ACROSS THE
CWA THROUGH THE SHORT TERM PERIOD...THOUGH I DID TRY TO TIME OUT THE
PERIODS BETWEEN WEAK SHORTWAVES FOR POSSIBLE LULLS IN COVERAGE. I
ALSO BUMPED UP QPF TO REFLECT PERIODS OF MODERATE-HEAVY PRECIP
POTENTIAL. THERE IS ALSO SOME POTENTIAL FOR FOG DEVELOPMENT LATE
TONIGHT/EARLY FRIDAY...HOWEVER SURFACE PATTERN COULD BE CHAOTIC IF
THUNDERSTORM ACTIVITY IS ONGOING...AND DECIDED NOT TO INCLUDE
MENTION WITH THIS UPDATE. TEMPS TONIGHT AND FRIDAY ARE TRICKY AS
MODELS WOULD SUPPORT SHOWERS/THUNDERSTORMS ACROSS THE REGION THROUGH
THESE PERIODS...AND FRONTAL POSITION IS STILL UNCERTAIN.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 PM MDT THU MAY 22 2014
MAIN FORECAST CONCERNS HOW LONG WILL UPCOMING WET PERIOD LAST AND
HOW MUCH WE WILL GET DURING THIS TIME WHICH LEAD TO HYDRO ISSUES.
SATELLITE SHOWING AN AMPLIFIED PATTERN FROM THE PACIFIC INTO NORTH
AMERICA. FOR OUR AREA SITUATION FOR THE FORESEEABLE FUTURE WILL BE
CONTROLLED BY SPEED AND LOCATION OF UPPER LOW NOW CUTTING OVER THE
SOUTHWEST PORTION OF THE COUNTRY. FLOW BEHIND THIS SYSTEM ALONG
WITH STRONGER JET WINDS AND HEIGHT FALLS TO ITS SOUTH SHOWING SLOW
MOVEMENT AND A FURTHER SOUTH MOVEMENT WILL CONTINUE. STATIONARY
FRONT CONTINUES TO BE TO OUR SOUTH AND WEST WITH THE SOUTHERN
POSITION ROUGHLY ALONG THE KANSAS BORDER.
AT JET LEVEL...MODELS APPEARED TO DO FINE. AT MID LEVELS...THE
MODELS TENDED TO BE TOO FAR SOUTH AND EAST WITH THE SOUTHWEST UPPER
LOW. HERE AND OVERALL THE UKMET WAS DOING A LITTLE BETTER THAN THE
GFS AND CANADIAN. THE NAM WAS DOING A LITTLE BETTER THAN THE ECMWF
ON THE SURFACE WIND AND PRESSURE FIELD. THE GFS WAS DOING A LITTLE
BETTER THAN THE CANADIAN AND SREF ON THE LOW LEVEL THERMAL FIELD.
FRIDAY NIGHT...CONTINUATION OF WHAT IS STARTING DURING THE DAY.
LARGE AREA OF THUNDERSTORMS/HEAVY RAINFALL MOVES ACROSS THE AREA
FROM SOUTHWEST TO NORTHEAST. IT LOOKS LIKE THERE SHOULD BE A LULL IN
THE PRECIPITATION TOWARD THE END OF THE NIGHT. AT THAT TIME...MODELS
ARE SHOWING A NEARLY SATURATED BOUNDARY LAYER AIR MASS. IF NO
RAINFALL IS OCCURRING THERE LOOKS LIKE THERE WILL BE A GOOD CHANCE
OF AREAS OF FOG DEVELOPING.
SATURDAY/SATURDAY NIGHT...AFTER OVERNIGHT SHORTWAVE TROUGH MOVES
THROUGH THE MID LEVELS DRY OUT AND SHOULD HAVE A BRIEF TIME PERIOD
WHERE LITTLE TO NO PRECIPITATION SHOULD BE OCCURRING. AREAS OF FOG
SHOULD CONTINUE THROUGH THE MORNING. MODELS ARE IN GENERAL
AGREEMENT OF HAVING THE UPPER LOW NEAR THE ARIZONA/NEW MEXICO
BORDER BY LATE IN THE AFTERNOON. ANOTHER SHORTWAVE ROTATES IN FROM
THE SOUTH AS DIFLUENT FLOW ALOFT MOVES OVER THE AREA. MODELS ARE
TRYING TO DRY OUT THE AIR MASS WITH THIS FLOW IN PLACE AND AM NOT
BUYING THIS RIGHT NOW. SHOULD BE ANOTHER ROUND OF THUNDERSTORMS
WITH MODERATE TO HEAVY RAINFALL.
SUNDAY...SOME DIFFERENCE ON POSITION OF THE UPPER LOW IS SHOWN BY
THE ENSEMBLES AND DETERMINISTIC MODELS WHICH AFFECTS MANY THINGS BUT
UPPER JET LOOKS TO BE NEAR OR OVER THE WESTERN HALF OF THE AREA.
AREA IS STILL IN SOUTHERLY FLOW ALOFT WITH LOW LEVEL ALSO
CONTINUING TO BRING IN MOISTURE. A SHORTWAVE ROTATES THROUGH THIS
WHILE A UPPER JET AXIS ESTABLISHES ITSELF OVER THE WESTERN HALF OF
THE AREA. ONCE AGAIN MODELS ARE SHOWING THE AIR MASS DRYING AND AM
NOT SURE ABOUT THAT. THERE SHOULD BE A CONTINUED CHANCE OF
THUNDERSTORMS.
SUNDAY NIGHT THROUGH THURSDAY...MODEL HANDLING OF UPPER LOW BY
ENSEMBLES AND DETERMINISTIC OUTPUT ARE SHOWING DIFFERENCES. ALTHOUGH
THERE IS A GENERAL TENDENCY OF SLOWING THE LOW OR KEEPING IT NEARLY
STATIONARY SUNDAY NIGHT INTO MONDAY WITH A BETTER AGREEMENT IN
HAVING THE CIRCULATION FURTHER SOUTH. MODELS ACTUALLY TAKE THIS
SYSTEM THROUGH MONDAY INTO MONDAY NIGHT IN A FAVORABLE POSITION TO
BE IN WRAP AROUND/MID LEVEL DEFORMATION ZONE. ALL THESE DIFFERENCES
NOT SURPRISING WITH THIS SINCE MODELS USUALLY DO HAVE A PROBLEM WITH
THESE KIND OF SYSTEMS AND THIS IS RATHER UNUSUAL FOR THIS TIME OF
YEAR.
THE CRH_INIT GAVE ME CHANCE POPS SUNDAY NIGHT INTO MONDAY WITH
SLIGHT CHANCES GIVEN MONDAY NIGHT. AM CONCERNED THAT THIS PERIOD
COULD END UP BEING WETTER...ESPECIALLY MONDAY AND MONDAY NIGHT. AM
CONTENT RIGHT NOW IN LEAVING THIS AS IS SINCE THERE ARE HIGH CHANCE
POPS IN THERE. WITH THAT MONDAY HIGH TEMPERATURES COULD BE COOLER
AND OVERALL MAY NOT BE THE MOST PLEASANT MEMORIAL DAY. BY THE TIME
MONDAY ENDS...A SUBSTANTIAL AMOUNT OF PRECIPITATION SINCE TODAY
COULD HAVE OCCURRED AND MAY BE EXPERIENCING HYDRO PROBLEMS THROUGH
MOST OF THIS PERIOD.
ON TUESDAY...MODELS STILL NOT SHOWING THE SYSTEM NOT TOO FAR TO THE
EAST AND SOUTH AT THE BEGINNING OF THE DAY. THIS DAY COULD DEFINITELY
BE COOLER AND WETTER AS WELL BUT EVERYONE IS CONTENT IN LEAVING AS IS
AND DO NOT BLAME THEM WITH THE MODEL DIFFERENCES. THERE IS SOME
MOVEMENT TO THE SOUTH AND EAST THROUGH TUESDAY NIGHT.
PROBABLY THE MOST UNCERTAIN TIME PERIOD IS WEDNESDAY INTO THURSDAY.
THE ECMWF AND GFS MOVE THE SYSTEM ABOUT THE SAME AMOUNT TO THE
EAST. HOWEVER...THE GFS IS FURTHER SOUTH. THE GFS HAS MORE RIDGING
OVER OUR AREA THAN THE ECMWF. THE ECMWF EVEN STARTS TO RETROGRADE
THE SYSTEM A LITTLE DURING THIS TIME PERIOD. THE AIR MASS STILL LOOKS
MOIST ENOUGH TO SUPPORT CONVECTION WITH SOME SHORTWAVE TROUGHS MOVING
THROUGH WITH THE ECMWF LOOKING A LITTLE MORE FAVORABLE. CRH_INIT
DOES HAVE SOME LOW CHANCE POPS IN THERE FROM LATE WEDNESDAY INTO
THURSDAY. THIS MAY BE A BIT WET BUT THIS IS CONVECTIVE SEASON AND
THESE POPS ACTUALLY FIT CLIMATOLOGY. SO NOT ONLY DID I NOT CHANGE
ANY OF THE POPS BUT OVERALL CHANGED NOTHING ELSE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1122 AM MDT THU MAY 22 2014
THROUGH THE FIRST 12HR OF THE TAF PERIOD THE PRIMARY AVIATION
CONCERN WILL THE THUNDERSTORM ACTIVITY EXPECTED TO DEVELOP THIS
AFTERNOON AND SPREAD NORTHEAST OVER BOTH TERMINALS. BEST COVERAGE
WILL BE LATE AFTERNOON THROUGH THE LATE NIGHT TONIGHT
PERIOD...WITH SCATTERED SHOWERS/ISO THUNDER THEN LINGERING THROUGH
THE REST OF THE TAF PERIOD. WILL NEED TO MONITOR RADAR TRENDS AND
INTENSITY IN THE EVENT TEMPORARY IFR/MVFR CONDITIONS DEVELOP WITH
THUNDERSTORM ACTIVITY. AS THIS ACTIVITY IS WINDING DOWN MOISTURE
POOLING ALONG FRONTAL ZONE MAY LEAD TO FOG AND LOW STRATUS
DEVELOPMENT ALONG THE INTERSTATE 70 CORRIDOR...WITH LIFR CONDITIONS
POSSIBLE BY 12Z AT KGLD (AS INDICATED BY SOME GUIDANCE). IT IS WAY
TOO UNCERTAIN AT THIS POINT CONSIDERING THUNDERSTORM ACTIVITY
COULD COMPLICATE SURFACE PATTERN...AND THUS THE POTENTIAL FOR FOG.
FOR NOW I HAVE ONLY MENTIONED 3SM BR AROUND 12Z AT KGLD TO ACCOUNT
FOR THIS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
351 PM CDT Thu May 22 2014
.SHORT TERM...(This Evening through Friday)
Issued at 350 PM CDT THU MAY 22 2014
A broad closed upper low was located across southern CA this
afternoon. A minor H5 shortwave trough was lifting northeast across
south central KS and was providing enough ascent for an area of
showers and thunderstorms across east central and central KS.
At the surface an outflow boundary extended from near Fort Scott,
KS, then extended west-northwest to near Cassoday before extending
southwest, east of ICT into northwest OK. The 19Z SPC mesoscale
EMC RUC showed 1500 ML CAPE along and south of the OFB across south
central and southeast KS. The instability decreases across east
central and northeast KS, with MLCAPES less than 500 J/KG along and
north of I-70. The greatest chance for stronger storms this
afternoon and early evening will be along and south of I-35, where
the stronger thunderstorms may produce pea to penny size hail and
wind gusts of 40 to 50 MPH. Across the remainder of east central KS
the greatest hazard will be brief heavy rainfall.
Tonight, once the minor H5 trough lifts northeast into northern MO,
the thunderstorms will push east of the CWA. Thunderstorms
developing across eastern CO late this afternoon will congeal into
one or two complexes of thunderstorms and track east and southeast
across western KS during the evening hours and may move into north
central KS after midnight, then across portions of east central KS
through the early morning hours of Friday. At this time the best
rain chances late tonight will be along and south of a Concordia, to
Manhattan, to Ottawa line, but this will be more of mesoscale
forecast and will depend on where the thunderstorms complexes
develop and how they will track during the evening hours. The
primary hazards from the thunderstorms later tonight will be pea to
penny size hail with locally heavy rainfall.
Friday...after the morning complex of thunderstorms weakens and
shifts east of the CWA, additional thunderstorms will redevelop
along the leftover outflow boundaries during the afternoon hours.
The effective shear looks to be rather weak, so any thunderstorms
that develop across northeast KS Tuesday afternoon should be pulse
storms with the primary hazard being small hail, gusty winds and
brief heavy rainfall. The best chances for thunderstorms Friday
afternoon will occur across the western and southern counties,
closer to the surface outflow boundary/front. Highs on Friday will
be in the mid to upper 70s.
.LONG TERM...(Friday Night through Thursday)
Issued at 350 PM CDT THU MAY 22 2014
The extended forecast will be noted with several chances for showers
and thunderstorms as a very slow-moving system moves through the
region.
By Friday night, models are in very good agreement in having a
closed-off low anchored over the southwestern U.S. and slowly
progress east-northeastward toward the region through the weekend.
As a result, southwesterly flow aloft will prevail with ample
moisture surging into the area. There looks to be a decent chance
for showers and thunderstorms Friday night into Saturday evening as models
suggest a shortwave developing along the lee side of the mid-level
trough and tracking into the area. While models suggest MUCAPE
values could be upwards of 1000-1500 J/kg, 0-6km bulk shear values
continue to look extremely low at less than 20kts. As a result, the
probability of severe weather still looks to be very low, however
cannot completely rule out the slight chance for small hail or some
stronger winds from any stronger storms that develop. The main
concern with this activity will be for heavy rainfall as soundings
show a very deep moist adiabatic profile with PWAT values upwards of
1.50 to 1.75 inches. If these rounds of showers and thunderstorms
end up tracking over the same areas, then we could see some
localized flash flooding.
By the latter part of the weekend into next week, the models
certainly begin to struggle in handling the details of this
approaching system. With that in mind, some models are suggesting
that the region may be between shortwaves Sunday and Sunday night,
so precipitation chances are lower during this period with any
activity likely being more scattered in nature. On Monday, the
mid-level low should be progressing towards western Kansas and the
Texas/Oklahoma panhandles. There looks to be a decent chance for
showers and thunderstorms on Monday as another shortwave tracks near
the area. Beyond Monday, as previously mentioned, the models
struggle with the tracking and timing of any additional shortwaves
as the mid-level low finally tracks over or just south of the area
Tuesday night through Wednesday. Additionally, there are very
notable differences in the tracking of the center of this low, as
the ECMWF keeps it just south of the forecast area with the GFS
having it dive much further south. Due to the large model
uncertainty, made only minor adjustments to the consensus forecast
with slight to low-end chance PoPs in place Monday night through
Wednesday night. The potential for severe storms next week continues
to be low.
Between the prolonged period of cloud cover and not much in the way
of temperature advection, expect temperatures to remain fairly
steady through the period with highs generally in the mid 70s to low
80s and lows in the 60s.
&&
.AVIATION...(For the 18Z TAFs through 18Z Friday Afternoon)
Issued at 1231 PM CDT THU MAY 22 2014
Thunderstorms are developing just south and east of the MHK
terminal, some of these storms may affect MHK in the next couple
hours. Some of these storms may reach TOP and FOE by 19Z. After
00Z there will be a break from thunderstorms but late tonight and
early Friday, thunderstorm chances may increase. Expect mainly VFR
conditions with some MVFR ceilings in vicinity of thunderstorms,
along with reduced visibilities and gusty winds.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Hennecke
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
346 PM CDT Thu May 22 2014
...Update to short term...
.SHORT TERM...(This evening through Friday)
ISSUED AT 346 PM CDT THU MAY 22 2014
Tonight:
Main concern is dealing with orographic convection to the west. Afternoon
radar mosaic shows considerable thunderstorm activity across Colorado
and New Mexico. MCS propagation vectors support the eastward translation
of this activity and will eventually reach far SW Kansas by evening.
The HRRR is insistent in generating an MCS with a cold pool. This model
does seem to be - at times- too aggressive with cold pool generation.
Still, enough isentropic lift and moisture advection supports ramping
up the pops this evening. Think the main concern is heavy rainfall as
the 12Z KDDC raob PWAT is between the 75th percentile and the +2SD mark.
This is statistically significant. Bulk shear is far from reaching supercell
archetype. Secondary threat to heavy rainfall is outflow winds, which
could impact far western Kansas along and west of Highway 83. The boundary
layer will become more stable this evening, so that could mitigate any
momentum transfer issues. In addition to convection, have increased
QPF more in line with WPC guidance. Most of the mesoscale models (HRRR/WRF/4
km NAM) all suggest that a good chunk of the region might see 0.50-1.00"
from tonights and tomorrow thunderstorm activity.
Tomorrow:
Have ramped up pops again by afternoon and evening as PWAT remains near
an 1.00" and isentropic lift/warm air advection continues through the
day. Moist adiabatic thermodynamic skew-t/log-p`s and also slow MCS
propagation vectors suggest that heavy rainfall is still a threat for
tomorrow. Highest pops will be during the afternoon to 00Z as diurnally
induced instability increases. Again, would not be surprised to see
decent rainfall amounts through 7 pm tomorrow night, as alluded to
above.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 235 PM CDT THU MAY 22 2014
Medium range models indicate a southwest flow aloft prevailing
across the Western High Plains Saturday as a closed off upper level
low shifts slowly eastward across the Four Corners Region. As the
system approaches, increased divergence aloft downstream of the
trough axis will intensify across the high plains of eastern
Colorado, western Kansas, and the panhandle of Oklahoma, especially
into Saturday evening. Meanwhile, a prevailing low level
south-southeasterly flow will continue to draw additional moisture
into the state with H85 dewpoints nearing 15C. Although the flow
aloft is expected to remain generally weak, GFS/ECMWF model
soundings do show some marginal directional shear along with SBCAPE
values in excess of 1500 J/KG. As H5 vort maxima cycle northeast out
of the trough axis into the high plains, shower and thunderstorm
development is likely with some chance for marginally severe
weather possible. However, a bigger concern may be the potential
for brief periods of heavy rainfall with model soundings also
showing PW values well over one inch.
Similar conditions will exist Sunday as the closed off upper level
low moves across the Rockies into the Western High Plains. However,
a few more thunderstorms may be possible as an upper level jet noses
northward into southwest Kansas Sunday afternoon while a developing
dryline sharpens near the Colorado border. In addition, GFS/ECMWF
model soundings indicate an inverted V profile by Sunday afternoon
with SBCAPE values pushing above 2000 J/KG. Although speed shear
looks a little more favorable than Saturday, directional shear
does not which may limit the strength of any developing storms.
However, the potential for significant rainfall lingers with PW
values remaining fairly high with values near to a little above
one inch. Shower and thunderstorm potential shifts eastward more
into central Kansas Monday as the closed off low pushes further
east into western Kansas. Drier conditions are likely by Wednesday
as weak upper level ridging fills in across the Western High
Plains in wake of the departing upper level low.
Fairly mild temperatures are likely Saturday as a cooler air mass
remains locked in across the Western High Plains The GFS/ECMWF show
H85 temperatures changing little from Friday with the mid teens(C)
across central Kansas to the upper teens(C) out near the Colorado
border. Due to expected increased cloud cover and areas of precip,
look for highs up into the upper 70s(F) to near 80F. Similar
temperatures are likely into Monday before a gradual warming
trend begins by mid week as weak upper level ridging develops
across the Intermountain West.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1200 PM CDT THU MAY 22 2014
Somewhat of an uncertain forecast in regards to convective placement/timing.
Followed HRRR guidance for this evening, which shows storms moving out
of SE Colorado and impacting KDDC/KGCK around 00Z. Other models show
less storms, but given the moist atmosphere, it will not take much to
spark a storm. A greater chance of higher coverage is expected through
the overnight as another cluster moves across. Would not rule out MVFR
in the heavier thunderstorm activity, but cigs should mainly be VFR
averaged out over time and space.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 79 61 80 / 70 60 60 60
GCK 61 78 60 81 / 70 60 60 60
EHA 59 76 59 80 / 70 40 50 60
LBL 61 76 61 81 / 70 60 60 60
HYS 62 78 62 80 / 40 60 60 50
P28 66 80 64 82 / 40 60 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...JJohnson
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS GOODLAND KS
148 PM MDT THU MAY 22 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 148 PM MDT THU MAY 22 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS LARGE CLOSED UPPER OVER
SOUTHERN CALIFORNIA WITH RIDGE ACROSS PLAINS AND SOUTHEASTERN US.
SOUTHERLY/DIFLUENT FLOW IS IN PLACE ACROSS THE SOUTHERN PLAINS AND
ROCKIES WITH MOIST PLUME EXTENDING FROM PACIFIC NORTH WITHIN THIS
FLOW. AT THE SURFACE A STALLED FRONT IS ANALYZED ACROSS SOUTHERN KS
AND ACROSS OK/TX PANHANDLES. UPSTREAM RADARS SHOW THUNDERSTORM
ACTIVITY ALREADY DEVELOPING ACROSS NORTHEAST NEW MEXICO AND ALONG
THE FRONT RANG WITH A NORTHERLY PROGRESSION.
UPPER LEVEL ENERGY ROTATING THROUGH THE UPPER FLOW ON THE EASTERN
EDGE OF THE UPPER TROUGH WE WILL CONTINUE TO SUPPORT
SHOWER/THUNDERSTORM DEVELOPMENT. ANOMALOUSLY MOIST AIR MASS (PWATS
STANDARD DEVIATIONS ABOVE NORMAL) WILL LINGER TONIGHT THROUGH
TOMORROW.
FOR TONIGHT...THUNDERSTORMS ARE DEVELOPING IN PROXIMITY TO LARGE
SCALE DIFFLUENT FLOW OVER NEW MEXICO AND CENTRAL COLORADO. TD VALUES
AROUND 60F HAS LEAD TO SB CAPE 1500-2000 J/KG. AIR MASS BUILDING
OVER OUR CWA. GUIDANCE SHOWS MU CAPE THROUGH FRIDAY AROUND 2000 J/KG
OVER OUR CWA. GUIDANCE SUPPORTS THUNDERSTORM ACTIVITY UPSTREAM FROM
OUR CWA MERGING INTO CLUSTER/THUNDERSTORM COMPLEX AND SPREADING
NORTH INTO OUR CWA. WITH ELEVATED FRONTAL ZONE GENERALLY LINGERING
NEAR THE I-70 CORRIDOR AND MOISTURE POOLING/INSTABILITY LINGERING WE
SHOULD SEE A GOOD PATTERN FOR THIS ACTIVITY INCREASING IN COVERAGE.
0-6KM WIND IS 15KT OR LESS...HOWEVER WIND PROFILES BELOW 800MB ARE
VERY WEAK ALONG FRONTAL ZONE OUT OF THE EAST...WHILE 400-250MB WINDS
ARE STRAIGHT OUT OF THE WEST. IN ADDITION TO THE ALREADY WET SIGNAL
THIS PATTERN SUPPORT BACK BUILDING OF THUNDERSTORMS ALONG FRONTAL
ZONE AND VERY SLOW PROPAGATION OF THUNDERSTORMS. CONFIDENCE IS
INCREASING IN AT LEAST A LOCALIZED FLOODING THREAT TONIGHT...BUT IM
NOT SURE HOW WIDESPREAD THIS WILL BE SO IM HOLDING OFF ON ISSUANCE
OF FLASH FLOOD WATCH. SHEER PROFILES ARE NOT THAT
IMPRESSIVE...HOWEVER WITH MODERATE INSTABILITY/GOOD MID LEVEL LAPSE
RATES...DAMAGING WINDS ASSOCIATED WITH COLD POOL DRIVEN
THUNDERSTORM COMPLEXES OR STRONG WIND/LARGE HAIL WITH PULSE TYPE
CONVECTION CANT BE RULED OUT.
GUIDANCE SHOW GOOD 850MB SUPPORT LINGERING OVERNIGHT AND MODELS
CONTINUE TO LINGER SHOWERS/THUNDERSTORMS THROUGH TOMORROW
AFTERNOON...WITH AN ENHANCEMENT IN ACTIVITY AS SURFACE FRONT STALLS
ALONG KS/NE STATE LINE. I WAS COMFORTABLE LINGERING POPS ACROSS THE
CWA THROUGH THE SHORT TERM PERIOD...THOUGH I DID TRY TO TIME OUT THE
PERIODS BETWEEN WEAK SHORTWAVES FOR POSSIBLE LULLS IN COVERAGE. I
ALSO BUMPED UP QPF TO REFLECT PERIODS OF MODERATE-HEAVY PRECIP
POTENTIAL. THERE IS ALSO SOME POTENTIAL FOR FOG DEVELOPMENT LATE
TONIGHT/EARLY FRIDAY...HOWEVER SURFACE PATTERN COULD BE CHAOTIC IF
THUNDERSTORM ACTIVITY IS ONGOING...AND DECIDED NOT TO INCLUDE
MENTION WITH THIS UPDATE. TEMPS TONIGHT AND FRIDAY ARE TRICKY AS
MODELS WOULD SUPPORT SHOWERS/THUNDERSTORMS ACROSS THE REGION THROUGH
THESE PERIODS...AND FRONTAL POSITION IS STILL UNCERTAIN.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 324 AM MDT THU MAY 22 2014
SUNDAY THROUGH WEDNESDAY...THE UPPER LEVEL CLOSED LOW OVER THE
SOUTHWESTERN UNITED STATES WILL OPEN UP INTO A TROUGH AS IT MOVES
EAST INTO THE CENTRAL PLAINS. THIS TROUGH WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH THE BEGINNING OF THE EXTENDED AS
VORTICITY CIRCULATES AROUND IT. TEMPERATURES THROUGH THE BEGINNING
OF THE EXTENDED WILL REMAIN NEAR NORMAL...WITH HIGHS IN THE MID 70S
TO LOW 80S ON SUNDAY AND MONDAY. AS THE UPPER TROUGH MOVES
EAST...RIDGING WILL MOVE INTO THE PLAINS BY MIDWEEK. THIS RIDGING
WILL BRING A BRIEF PERIOD OF DRY WEATHER TO THE CWA ON TUESDAY
BEFORE THE NEXT SHORTWAVE TROUGH BRINGS THE CHANCE FOR SHOWERS AND
THUNDERSTORMS BACK TO THE CWA BY WEDNESDAY. A SERIES OF SURFACE
TROUGHS WILL ALSO SET UP IN EASTERN COLORADO THROUGHOUT THE
EXTENDED...WHICH WILL BRING A FEW WIND SHIFTS AND COULD BRING
SURFACE BOUNDARIES THAT AID IN SHOWER AND THUNDERSTORM DEVELOPMENT
THROUGHOUT MOST OF THE EXTENDED. TEMPERATURES BEGIN TO WARM UP ON
TUESDAY AS THE RIDGE MOVES OVER THE PLAINS...WITH HIGHS IN THE LOW
TO MID 80S WHICH WILL CONTINUE INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1122 AM MDT THU MAY 22 2014
THROUGH THE FIRST 12HR OF THE TAF PERIOD THE PRIMARY AVIATION
CONCERN WILL THE THUNDERSTORM ACTIVITY EXPECTED TO DEVELOP THIS
AFTERNOON AND SPREAD NORTHEAST OVER BOTH TERMINALS. BEST COVERAGE
WILL BE LATE AFTERNOON THROUGH THE LATE NIGHT TONIGHT
PERIOD...WITH SCATTERED SHOWERS/ISO THUNDER THEN LINGERING THROUGH
THE REST OF THE TAF PERIOD. WILL NEED TO MONITOR RADAR TRENDS AND
INTENSITY IN THE EVENT TEMPORARY IFR/MVFR CONDITIONS DEVELOP WITH
THUNDERSTORM ACTIVITY. AS THIS ACTIVITY IS WINDING DOWN MOISTURE
POOLING ALONG FRONTAL ZONE MAY LEAD TO FOG AND LOW STRATUS
DEVELOPMENT ALONG THE INTERSTATE 70 CORRIDOR...WITH LIFR CONDITIONS
POSSIBLE BY 12Z AT KGLD (AS INDICATED BY SOME GUIDANCE). IT IS WAY
TOO UNCERTAIN AT THIS POINT CONSIDERING THUNDERSTORM ACTIVITY
COULD COMPLICATE SURFACE PATTERN...AND THUS THE POTENTIAL FOR FOG.
FOR NOW I HAVE ONLY MENTIONED 3SM BR AROUND 12Z AT KGLD TO ACCOUNT
FOR THIS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...ALW
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
238 PM CDT Thu May 22 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(Today and tonight)
ISSUED AT 350 AM CDT THU MAY 22 2014
Convection chances will be the main theme for the next 24 to 36
hours of forecast timeframe. Determining where those will be likely
to redevelop will be better suited for later in the day as the
atmosphere destabilizes again in collocation with the best low level
convergence of the stationary front or old outflow boundaries. Models
indicate precipitation already early in the day, possibly overdone
owing to the mean layer CAPE but not out the plausibility. If
easterly to southeasterly flow redevelops which appears likely,
another round of late afternoon or mainly late evening thunderstorms
is likely for any part of the area as is being shown in recent NMM/ARW
WRF model runs both (00 and 06 UTC runs). These evening MCS trends
were followed for the overall precipitation chance trends late today
and tonight. Model soundings this evening show generally
unidirectional flow rather than very strong low level veering which
would tend to support clusters or weak qlcs type storm structures.
In the meantime, the afternoon should be warm and humid. Most of the
model guidance indicates 80-s to around 90 across the southern
counties. Old convective outflow may moderate the temperature
heating curve from what the models produce.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 235 PM CDT THU MAY 22 2014
Medium range models indicate a southwest flow aloft prevailing
across the Western High Plains Saturday as a closed off upper level
low shifts slowly eastward across the Four Corners Region. As the
system approaches, increased divergence aloft downstream of the
trough axis will intensify across the high plains of eastern
Colorado, western Kansas, and the panhandle of Oklahoma, especially
into Saturday evening. Meanwhile, a prevailing low level
south-southeasterly flow will continue to draw additional moisture
into the state with H85 dewpoints nearing 15C. Although the flow
aloft is expected to remain generally weak, GFS/ECMWF model
soundings do show some marginal directional shear along with SBCAPE
values in excess of 1500 J/KG. As H5 vort maxima cycle northeast out
of the trough axis into the high plains, shower and thunderstorm
development is likely with some chance for marginally severe
weather possible. However, a bigger concern may be the potential
for brief periods of heavy rainfall with model soundings also
showing PW values well over one inch.
Similar conditions will exist Sunday as the closed off upper level
low moves across the Rockies into the Western High Plains. However,
a few more thunderstorms may be possible as an upper level jet noses
northward into southwest Kansas Sunday afternoon while a developing
dryline sharpens near the Colorado border. In addition, GFS/ECMWF
model soundings indicate an inverted V profile by Sunday afternoon
with SBCAPE values pushing above 2000 J/KG. Although speed shear
looks a little more favorable than Saturday, directional shear
does not which may limit the strength of any developing storms.
However, the potential for significant rainfall lingers with PW
values remaining fairly high with values near to a little above
one inch. Shower and thunderstorm potential shifts eastward more
into central Kansas Monday as the closed off low pushes further
east into western Kansas. Drier conditions are likely by Wednesday
as weak upper level ridging fills in across the Western High
Plains in wake of the departing upper level low.
Fairly mild temperatures are likely Saturday as a cooler air mass
remains locked in across the Western High Plains The GFS/ECMWF show
H85 temperatures changing little from Friday with the mid teens(C)
across central Kansas to the upper teens(C) out near the Colorado
border. Due to expected increased cloud cover and areas of precip,
look for highs up into the upper 70s(F) to near 80F. Similar
temperatures are likely into Monday before a gradual warming
trend begins by mid week as weak upper level ridging develops
across the Intermountain West.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1200 PM CDT THU MAY 22 2014
Somewhat of an uncertain forecast in regards to convective placement/timing.
Followed HRRR guidance for this evening, which shows storms moving out
of SE Colorado and impacting KDDC/KGCK around 00Z. Other models show
less storms, but given the moist atmosphere, it will not take much to
spark a storm. A greater chance of higher coverage is expected through
the overnight as another cluster moves across. Would not rule out MVFR
in the heavier thunderstorm activity, but cigs should mainly be VFR
averaged out over time and space.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 79 61 80 / 70 60 60 60
GCK 61 78 60 81 / 70 60 60 60
EHA 59 76 59 80 / 70 40 50 60
LBL 61 76 61 81 / 70 60 60 60
HYS 62 78 62 80 / 40 60 60 50
P28 66 80 64 82 / 40 60 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...JJohnson
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1200 PM CDT Thu May 22 2014
...Update to aviation...
.SYNOPSIS...
ISSUED AT 940 AM CDT THU MAY 22 2014
The 22.12Z 250-hPa map showed broad southwesterly flow aloft ahead of
a longwave trough across the Desert SW and extending into Kansas. At
500-hPa, a closed circulation was noted across California and Nevada.
Some mid-level moisture was advecting northward ahead of this pressure
perturbation. At the lower levels for KDDC, moisture advection was noted
for the RAOB with the total PWAT column at 1.08" (between the 75th percentile
and 2SD mark). The entire sounding is conducive to heavy rain. Wind
shear was pretty weak too. At the surface, a stationary boundary was
analyzed across Kansas with plenty of low level moisture across the
state (dew points in the 50s and 60s).
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 350 AM CDT THU MAY 22 2014
Convection chances will be the main theme for the next 24 to 36
hours of forecast timeframe. Determining where those will be likely
to redevelop will be better suited for later in the day as the
atmosphere destabilizes again in collocation with the best low level
convergence of the stationary front or old outflow boundaries. Models
indicate precipitation already early in the day, possibly overdone
owing to the mean layer CAPE but not out the plausibility. If
easterly to southeasterly flow redevelops which appears likely,
another round of late afternoon or mainly late evening thunderstorms
is likely for any part of the area as is being shown in recent NMM/ARW
WRF model runs both (00 and 06 UTC runs). These evening MCS trends
were followed for the overall precipitation chance trends late today
and tonight. Model soundings this evening show generally
unidirectional flow rather than very strong low level veering which
would tend to support clusters or weak qlcs type storm structures.
In the meantime, the afternoon should be warm and humid. Most of the
model guidance indicates 80-s to around 90 across the southern
counties. Old convective outflow may moderate the temperature
heating curve from what the models produce.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 411 AM CDT THU MAY 22 2014
The first several days of the long term period will see decent
chances for rain and thunderstorms across western and central
Kansas. At the beginning of the period, a closed upper low will be
situated over southwest Arizona while an upper level ridge axis will
extend from the northern High Plains into the lower Mississippi
Valley. A fairly deep layer of moist southerly flow will extend from
the western Gulf Coast into the eastern slopes of the Rockies. The
upper level low will gradually move east toward the central High
Plains through the weekend. Upper level disturbances rotating around
the upper low will periodically eject northward into the central
High Plains...bringing daily rounds of thunderstorms to the area
through Monday.
During the early to middle part of next week, another upper level
trough will move into western North America which will effectively
kick the central Plains upper low eastward out of the High Plains
toward the mid Mississippi Valley. Chances for showers and
thunderstorms will decrease significantly once the upper low moves
east of the region.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1200 PM CDT THU MAY 22 2014
Somewhat of an uncertain forecast in regards to convective placement/timing.
Followed HRRR guidance for this evening, which shows storms moving out
of SE Colorado and impacting KDDC/KGCK around 00Z. Other models show
less storms, but given the moist atmosphere, it will not take much to
spark a storm. A greater chance of higher coverage is expected through
the overnight as another cluster moves across. Would not rule out MVFR
in the heavier thunderstorm activity, but cigs should mainly be VFR
averaged out over time and space.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 87 62 81 61 / 30 60 50 60
GCK 86 60 80 60 / 30 60 50 50
EHA 86 59 80 59 / 40 70 40 40
LBL 87 61 81 61 / 40 70 50 40
HYS 84 61 81 62 / 30 60 60 60
P28 90 65 84 64 / 30 50 50 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Sugden
SHORT TERM...Russell
LONG TERM...Gerard
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
352 AM CDT Thu May 22 2014
...UPDATED SHORT TERM...
.SYNOPSIS...
ISSUED AT 350 AM CDT THU MAY 22 2014
An upper low was moving east into the desert southwest pushing
southerly difluent flow aloft into the southern Rockies. The 00 utc
500 and 700 mb analysis indicated some moisture flux in the mid
levels, but not very impressive at 700 mb across the southern High
Plains. Warm boundary layer air was in place through the entire
southern and central Plains with temperatures at 850 mb at 20 to 25
degrees C. After initial severe thunderstorms fed off the easterly
boundary layer upslope flow across NW and west central Kansas,
additional marginally severe/severe storms developed behind the
previous storms outflow and in a better mid level instability
environment after midnight across Ness Rush and Trego counties,
which approximated the earlier runs of the HRRR model. Radar
estimates following this convection as of around 130 am suggest an
inch to an inch and a half easily could have fallen across
northwest Ness county between Utica and Arnold.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 350 AM CDT THU MAY 22 2014
Convection chances will be the main theme for the next 24 to 36
hours of forecast timeframe. Determining where those will be likely
to redevelop will be better suited for later in the day as the
atmosphere destabilizes again in collocation with the best low level
convergence of the stationary front or old outflow boundaries. Models
indicate precipitation already early in the day, possibly overdone
owing to the mean layer CAPE but not out the plausibility. If
easterly to southeasterly flow redevelops which appears likely,
another round of late afternoon or mainly late evening thunderstorms
is likely for any part of the area as is being shown in recent NMM/ARW
WRF model runs both (00 and 06 UTC runs). These evening MCS trends
were followed for the overall precipitation chance trends late today
and tonight. Model soundings this evening show generally
unidirectional flow rather than very strong low level veering which
would tend to support clusters or weak qlcs type storm structures.
In the meantime, the afternoon should be warm and humid. Most of the
model guidance indicates 80-s to around 90 across the southern
counties. Old convective outflow may moderate the temperature
heating curve from what the models produce.
.LONG TERM...(Thursday night through Wednesday)
ISSUED AT 236 PM CDT WED MAY 21 2014
Thunderstorm chances will persist through the weekend as medium
range models continue to indicate a closed off upper level low
shifting ever so slowly eastward across the Desert Southwest.
As the system approaches, increased divergence aloft downstream
of the trough axis combined with an upper level jet lifting
northeastward into the Western High Plains will set the stage
for thunderstorm development across portions of central and
western Kansas each day through Sunday. Meanwhile, a prevailing
low level south-southeasterly flow will draw additional moisture
into the state with H85 dewpoints climbing well above 10C by
Sunday. GFS and ECMWF model soundings also show sufficient
instability with SBCAPE values in excess of 1000 to 1500 J/KG
while lapse rates steepen each afternoon through the weekend.
As a result, rain showers and thunderstorms can be expected each
day across parts of western and central Kansas.
Near normal temperatures are likely Friday as slightly cooler air
is cycled back into western Kansas on the backside of a broad
surface high in the Great Lakes Region. The GFS/ECMWF show H85
temperatures ranging from the mid to upper teens(C) across central
Kansas to the upper teens(C) out near the Colorado border. Highs
reaching 80F may be a struggle Friday afternoon with increased
cloud cover likely along with areas of precip. Similar
temperatures are forecast through the weekend with little change
expected to the overall air mass across the high plains of western
Kansas.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 1249 AM CDT THU MAY 22 2014
Scattered thunderstorms will continue for a few hours longer along
a low level wind convergence zone in proximity to steep low and
mid level lapse rates and moderate most unstable capes. A few large
cores ca be expected mainly in the vicinity of the HYS terminal
through 9z, which potential could cause strong surface downdrafts.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 87 62 81 61 / 30 60 50 60
GCK 86 60 80 60 / 30 60 50 50
EHA 85 59 80 59 / 40 70 40 40
LBL 87 61 81 61 / 40 70 50 40
HYS 84 61 81 62 / 30 60 60 60
P28 91 65 84 64 / 30 50 50 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Russell
SHORT TERM...Russell
LONG TERM...JJohnson
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1136 PM MDT WED MAY 21 2014
.UPDATE...
ISSUED AT 1054 PM MDT WED MAY 21 2014
UPDATED GRIDS AND ZONES FOR THE CANCELLATION OF SEVERE
THUNDERSTORM WATCH 170. THE SEVERE THREAT HAS DIMINISHED.
UPDATE ISSUED AT 913 PM MDT WED MAY 21 2014
UPDATED GRIDS AND ZONES FOR A CANCELLATION OF PART OF THE SEVERE
WATCH. EASTERN COLORADO AND PART OF NORTHWEST KANSAS IS NO LONGER
IN THE WATCH. THE WATCH CONTINUES FOR THE EASTERN PART OF THE WATCH.
&&
.SHORT TERM...(THIS AFTERNOON INTO TONIGHT)
ISSUED AT 205 PM MDT WED MAY 21 2014
MAIN CHANGE FOR THIS TIME PERIOD WAS TO SLOW THE ONSET OF
THUNDERSTORM DEVELOPMENT. FRONT WAS DRAPED RATHER FAR SOUTH AND
ALONG THE FRONT RANGE TO THE WEST. AN AREA OF SURFACE CONVERGENCE
EXTENDED FROM KIT CARSON AND CHEYENNE COUNTIES TOWARD THE
NORTHWEST. RATHER STRONG SURFACE WINDS OCCURRING OVER THE AREA AT
THIS TIME. SHORTWAVE TROUGH OVER NEW MEXICO IS EXPECTED TO MOVE
TOWARD THE NORTHEAST THROUGH THE NIGHT WITH A SLUG OF SUBTROPICAL
MOISTURE COMING IN ADVANCE OF IT. ALSO A RIGHT REAR QUADRANT OF
THE JET STARTS OVER THE SOUTHWEST HALF OF THE AREA LATE THIS
AFTERNOON INTO THE EVENING HOURS.
THIS IS ALL STARTING A LITTLE SLOWER THAN WHAT THE EARLIER FORECAST
HAD. AREA RADARS/SATELLITE/LIGHTNING DETECTION SHOW AN AREA/LINE
OF STORMS DEVELOPING FROM SOUTHWEST KANSAS INTO SOUTHEAST COLORADO
TO ALONG THE NORTHERN COLORADO FRONT RANGE. WHERE THE MAIN PROBLEM
IS FOR THIS FORECAST IS THAT THE MODELS DISAGREE ON WHERE TO PUT
THE MAIN SWATCH OF STORMS/QPF. SOME TAKE THE MAIN AREA OVER THE
NORTHWEST HALF...SOME OVER THE SOUTHEAST PORTION CLOSEST TO THE
FRONT AND SOME DO BOTH.
THE HRRR WHICH HAS BEEN DOING WELL RECENTLY HAS TRENDED FROM
TAKING A BROKEN SWATH OF PRECIPITATION FROM SOUTHWEST TO NORTHEAST
ACROSS THE ENTIRE CWA TO THE TWO DIFFERENT AREAS OVER THE SOUTHEAST
AND NORTHWEST. ALSO THE MODELS ARE ALSO INDICATING A COUPLE OF
DIFFERENT WAVES OF PRECIPITATION. ONE THIS EVENING WITH THIS
IN ITAL WAVE AND THEN ANOTHER ONE LATER TONIGHT. ALL IN ALL THERE
LOOKS TO BE SOME KIND OF PRECIPITATION MOVING ACROSS MOST OF THE
AREA...JUST NOT SURE EXACTLY WHERE.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 228 PM MDT WED MAY 21 2014
THE FOCUS/MAIN CONCERNS FOR THE LONG TERM FORECAST PERIOD ARE SEVERE
WEATHER CHANCES AND POTENTIAL FOR HEAVY RAINS. THE PRIMARY TIME FOR
SEVERE WEATHER WITHIN THE LONG-TERM FORECAST RESIDES ON THURSDAY
AND THURSDAY NIGHT. THREAT FOR HEAVY RAINS WILL BE HIGHEST FROM
THURSDAY THROUGH SATURDAY NIGHT.
ON THURSDAY...A LULL IN CONVECTIVE ACTIVITY SEEMS PROBABLE FOR
THURSDAY MORNING BEFORE ACTIVITY ONCE AGAIN RAMPS UP IN THE
AFTERNOON. IN A SIMILAR SCENARIO TO WEDNESDAY...THUNDERSTORMS
DEVELOP TO THE SOUTH AND WEST ALONG A STALLED FRONT...CONVECTIVE
OUTFLOWS AND THE FRONT RANGE. THUNDERSTORMS THEN SPREAD NORTHEAST
ACROSS THE FORECAST AREA. INSTABILITY MAY BE HIGHER THURSDAY
COMPARED TO TODAY...HOWEVER...THE SHEAR SIGNIFICANTLY DECREASES. DO
NOT THINK THE TORNADO OR SUPERCELL THREAT IS AS HIGH FOR THURSDAY
COMPARED TO WEDNESDAY. PULSE-LIKE HAIL STORMS AND CONVECTIVE
CLUSTERS SHOULD BE THE PRIMARY STORM MODES WITH LARGE HAIL AND
DAMAGING WINDS AS THE MAIN THREAT. SOME SIGNIFICANT HAIL AT OR ABOVE
2 INCHES REMAINS POSSIBLE.
FROM THURSDAY NIGHT THROUGH MONDAY...SHOWER AND THUNDERSTORM CHANCES
CONTINUE ACROSS THE FORECAST AREA AS THE UPPER LEVEL LOW REMAINS
OVER THE WESTERN UNITED STATES. HAVE ADVERTISED THE BEST CHANCES FOR
RAIN IN THE AFTERNOON AND EVENING EACH DAY AS SHORTWAVE TROUGHS PASS
THROUGH AND DAYTIME INSTABILITY IS HIGHEST. IT IS POSSIBLE THAT
CONVECTION CONTINUES THROUGHOUT THE NIGHT ON THURSDAY AND POSSIBLY
FRIDAY. THE UPPER LEVEL LOW PRESSURE SYSTEM EJECTS OVER THE PLAINS
MONDAY AND CLEARS OUT TO THE EAST BY TUESDAY. MODELS HAVE SLOWED THE
SYSTEM SLIGHTLY SO HAVE PULLED POPS BACK TO THE WEST SOME.
WITH RESPECT TO POTENTIAL FLASH FLOODING...AGAIN THE HIGHEST
POTENTIAL FOR THIS THREAT IS BETWEEN THURSDAY NIGHT AND SATURDAY
NIGHT. PRECIPITABLE WATER READINGS APPROACH TO EXCEED 2 STANDARD
DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. SEVERAL CLUSTERS WILL
PASS THROUGH WITH HEAVY RAIN RATES AND SUFFICIENT INSTABILITY. STILL
UNSURE ABOUT THIS BECOMING A WIDESPREAD FLOODING EVENT DUE TO
UNCERTAINTY IN EXACT STORM MOVEMENT. IF THERE WERE TO BE FLASH
FLOODING...THE MOST LIKELY LOCATION IS NORTHWEST KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1127 PM MDT WED MAY 21 2014
VFR CONDITIONS ARE EXPECTED FOR PART OF THE NIGHT AT KGLD AND
KMCK WITH STORMS MOVING OUT OF THE AREA. HOWEVER, FORECAST
SOUNDINGS INDICATE STRATUS WILL MOVE INTO THE SITES TOWARD
SUNRISE. THE NAM BOUNDARY LAYER MOISTURE PROG INDICATES THAT HIGH
RH DOES NOT PERSIST VERY LONG AND IS RATHER SPOTTY. THIS CASTS
UNCERTAINTY ON WHETHER THERE WILL BE ANY VISIBILITY RESTRICTIONS
DUE TO FOG. SOME MVFR CONDITIONS ARE POSSIBLE ESPECIALLY AT KMCK
BUT CANNOT RULE IT OUT AT KGLD EITHER. STRATUS WILL DISSIPATE QUICKLY
WITH VFR RETURNING BY MID MORNING. MORE THUNDERSTORMS ARE EXPECTED AT
BOTH SITES THURSDAY AFTERNOON AND EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...FS
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1157 PM CDT Wed May 21 2014
.UPDATE...
Issued at 1152 PM CDT WED MAY 21 2014
Short range models continue to slow convective development across
north central and northeast KS and have thus delayed POPs and
thunderstorm chances overnight. Still a wide variety of convective
development possibilities from the various short range models and
have not modified forecast beyond tonight due to uncertainty.
&&
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Thursday)
Issued at 311 PM CDT WED MAY 21 2014
Latest surface analysis shows surface trough extending northeast
from a low over the Texas Panhandle to near Topeka then into
northwest Missouri. Dew points have increased to around 66 degrees
to the south of the boundary in east central Kansas. Cu field has
developed along and to the north of the boundary. Convergence was
still weak and capping remains in place as CIN values range from 100
to 200 J/kg at 20Z. 0-6km shear of 40 to 50 kts over the CWA and
shear is forecast to decrease some overnight to around 30 to 40 kts.
Cape was running around 2000-2500 J/kg at late afternoon. If cap is
able to be overcome then isolated thunderstorms could develop and
could become severe with hail and and wind the main Hazards. Have
left small chances for thunderstorms from late afternoon and into
the early evening hours. There does not seem to be any weak waves
that would set anything off. The HRRR and the new 18Z NAM develop
some convection this evening along the frontal boundary and in area
of 850 mb convergence and theta advection. Have increase chances
after 03Z. The next area to watch remains convection moving off the
High Plains and/or developing across south central Kansas. Models
are showing that good moisture transport will focus into central
Kansas by 06Z then veering into northeast Kansas by 12Z with the
increase of the low level jet. Corfidi vectors suggest an eastward
movement to any MCS that would develop out in western Kansas.
Precipitable water values increase to around 1.5 inches along I-70
overnight. Isolated hail and strong winds will be possible with the
MCS as it moves across the state.
Thursday, there still could be some morning convection which will
leave outflow boundaries across the area along with the frontal
boundary. Shear is not as strong as today generally in the
20 to 30 kt range and is less favorable for supercells. There is a
wave that was moving across New Mexico this afternoon that is
progged to be moving into central Kansas on Thursday. Will continue
to keep chance pops going for now. Lows tonight will range from the
lower 60s along the Nebraska border to the upper 60s across east
central Kansas. Highs Thursday will range from the mid 70s in far
northeast Kansas to the mid 80s in east central Kansas.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 311 PM CDT WED MAY 21 2014
The surface front will sag south again Thursday night in wake of
the shortwave trough that will round the upper ridge during the
day Thursday. Proximity of the boundary along with 925-850mb
20-30kt flow moving atop the sfc-850mb boundary could lead to sct
thunderstorms overnight into early Friday. Some low chcs for pops again
Friday although the upper ridge over the area and better low level
focus across western KS suggests chcs are minimal this far east.
Another upper wave will move across the region Friday night into
Saturday so that should bring better chcs for scattered
thunderstorms.
The main upper low will drift into the region Sunday and Monday.
It would appear that Sunday night into Monday would bring the
higher rain chcs as the upper low approaches the area given we
will lack a low level focus both days. The upper low will finally
depart Tuesday so precip chcs will diminish then with a dry
weather expected by mid to late week.
&&
.AVIATION...(For the 06Z TAFs through 06Z Thursday Night)
Issued at 1152 PM CDT WED MAY 21 2014
Have delayed thunderstorm chances for TAF sites by a couple hours
due to slower development and movement of upper system. Beyond the
chances for convection tonight into Thur morning, would expect
another round to develop late afternoon or evening. VFR conditions
are expected outside of thundersorms.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GDP
SHORT TERM...53
LONG TERM...Omitt
AVIATION...GDP
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1055 PM MDT WED MAY 21 2014
.UPDATE...
ISSUED AT 1054 PM MDT WED MAY 21 2014
UPDATED GRIDS AND ZONES FOR THE CANCELLATION OF SEVERE
THUNDERSTORM WATCH 170. THE SEVERE THREAT HAS DIMINISHED.
UPDATE ISSUED AT 913 PM MDT WED MAY 21 2014
UPDATED GRIDS AND ZONES FOR A CANCELLATION OF PART OF THE SEVERE
WATCH. EASTERN COLORADO AND PART OF NORTHWEST KANSAS IS NO LONGER
IN THE WATCH. THE WATCH CONTINUES FOR THE EASTERN PART OF THE WATCH.
&&
.SHORT TERM...(THIS AFTERNOON INTO TONIGHT)
ISSUED AT 205 PM MDT WED MAY 21 2014
MAIN CHANGE FOR THIS TIME PERIOD WAS TO SLOW THE ONSET OF
THUNDERSTORM DEVELOPMENT. FRONT WAS DRAPED RATHER FAR SOUTH AND
ALONG THE FRONT RANGE TO THE WEST. AN AREA OF SURFACE CONVERGENCE
EXTENDED FROM KIT CARSON AND CHEYENNE COUNTIES TOWARD THE
NORTHWEST. RATHER STRONG SURFACE WINDS OCCURRING OVER THE AREA AT
THIS TIME. SHORTWAVE TROUGH OVER NEW MEXICO IS EXPECTED TO MOVE
TOWARD THE NORTHEAST THROUGH THE NIGHT WITH A SLUG OF SUBTROPICAL
MOISTURE COMING IN ADVANCE OF IT. ALSO A RIGHT REAR QUADRANT OF
THE JET STARTS OVER THE SOUTHWEST HALF OF THE AREA LATE THIS
AFTERNOON INTO THE EVENING HOURS.
THIS IS ALL STARTING A LITTLE SLOWER THAN WHAT THE EARLIER FORECAST
HAD. AREA RADARS/SATELLITE/LIGHTNING DETECTION SHOW AN AREA/LINE
OF STORMS DEVELOPING FROM SOUTHWEST KANSAS INTO SOUTHEAST COLORADO
TO ALONG THE NORTHERN COLORADO FRONT RANGE. WHERE THE MAIN PROBLEM
IS FOR THIS FORECAST IS THAT THE MODELS DISAGREE ON WHERE TO PUT
THE MAIN SWATCH OF STORMS/QPF. SOME TAKE THE MAIN AREA OVER THE
NORTHWEST HALF...SOME OVER THE SOUTHEAST PORTION CLOSEST TO THE
FRONT AND SOME DO BOTH.
THE HRRR WHICH HAS BEEN DOING WELL RECENTLY HAS TRENDED FROM
TAKING A BROKEN SWATH OF PRECIPITATION FROM SOUTHWEST TO NORTHEAST
ACROSS THE ENTIRE CWA TO THE TWO DIFFERENT AREAS OVER THE SOUTHEAST
AND NORTHWEST. ALSO THE MODELS ARE ALSO INDICATING A COUPLE OF
DIFFERENT WAVES OF PRECIPITATION. ONE THIS EVENING WITH THIS
IN ITAL WAVE AND THEN ANOTHER ONE LATER TONIGHT. ALL IN ALL THERE
LOOKS TO BE SOME KIND OF PRECIPITATION MOVING ACROSS MOST OF THE
AREA...JUST NOT SURE EXACTLY WHERE.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 228 PM MDT WED MAY 21 2014
THE FOCUS/MAIN CONCERNS FOR THE LONG TERM FORECAST PERIOD ARE SEVERE
WEATHER CHANCES AND POTENTIAL FOR HEAVY RAINS. THE PRIMARY TIME FOR
SEVERE WEATHER WITHIN THE LONG-TERM FORECAST RESIDES ON THURSDAY
AND THURSDAY NIGHT. THREAT FOR HEAVY RAINS WILL BE HIGHEST FROM
THURSDAY THROUGH SATURDAY NIGHT.
ON THURSDAY...A LULL IN CONVECTIVE ACTIVITY SEEMS PROBABLE FOR
THURSDAY MORNING BEFORE ACTIVITY ONCE AGAIN RAMPS UP IN THE
AFTERNOON. IN A SIMILAR SCENARIO TO WEDNESDAY...THUNDERSTORMS
DEVELOP TO THE SOUTH AND WEST ALONG A STALLED FRONT...CONVECTIVE
OUTFLOWS AND THE FRONT RANGE. THUNDERSTORMS THEN SPREAD NORTHEAST
ACROSS THE FORECAST AREA. INSTABILITY MAY BE HIGHER THURSDAY
COMPARED TO TODAY...HOWEVER...THE SHEAR SIGNIFICANTLY DECREASES. DO
NOT THINK THE TORNADO OR SUPERCELL THREAT IS AS HIGH FOR THURSDAY
COMPARED TO WEDNESDAY. PULSE-LIKE HAIL STORMS AND CONVECTIVE
CLUSTERS SHOULD BE THE PRIMARY STORM MODES WITH LARGE HAIL AND
DAMAGING WINDS AS THE MAIN THREAT. SOME SIGNIFICANT HAIL AT OR ABOVE
2 INCHES REMAINS POSSIBLE.
FROM THURSDAY NIGHT THROUGH MONDAY...SHOWER AND THUNDERSTORM CHANCES
CONTINUE ACROSS THE FORECAST AREA AS THE UPPER LEVEL LOW REMAINS
OVER THE WESTERN UNITED STATES. HAVE ADVERTISED THE BEST CHANCES FOR
RAIN IN THE AFTERNOON AND EVENING EACH DAY AS SHORTWAVE TROUGHS PASS
THROUGH AND DAYTIME INSTABILITY IS HIGHEST. IT IS POSSIBLE THAT
CONVECTION CONTINUES THROUGHOUT THE NIGHT ON THURSDAY AND POSSIBLY
FRIDAY. THE UPPER LEVEL LOW PRESSURE SYSTEM EJECTS OVER THE PLAINS
MONDAY AND CLEARS OUT TO THE EAST BY TUESDAY. MODELS HAVE SLOWED THE
SYSTEM SLIGHTLY SO HAVE PULLED POPS BACK TO THE WEST SOME.
WITH RESPECT TO POTENTIAL FLASH FLOODING...AGAIN THE HIGHEST
POTENTIAL FOR THIS THREAT IS BETWEEN THURSDAY NIGHT AND SATURDAY
NIGHT. PRECIPITABLE WATER READINGS APPROACH TO EXCEED 2 STANDARD
DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. SEVERAL CLUSTERS WILL
PASS THROUGH WITH HEAVY RAIN RATES AND SUFFICIENT INSTABILITY. STILL
UNSURE ABOUT THIS BECOMING A WIDESPREAD FLOODING EVENT DUE TO
UNCERTAINTY IN EXACT STORM MOVEMENT. IF THERE WERE TO BE FLASH
FLOODING...THE MOST LIKELY LOCATION IS NORTHWEST KANSAS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 535 PM MDT WED MAY 21 2014
VFR CONDITIONS DETERIORATE THIS EVENING AT KGLD AND KMCK AS A LINE
OF STORMS MOVES NORTHEAST IMPACTING KGLD AROUND 01Z AND KMCK BY
04Z. DO NOT EXPECT MORE THAN A COUPLE OF HOURS OF THUNDER AT
EITHER SITE. AFTER MIDNIGHT SOME MORE SHOWERS AND STORMS WILL
LINGER NEAR KGLD. FORECAST SOUNDINGS INDICATE POTENTIAL FOR
STRATUS AND MVFR CONDITIONS AT BOTH SITES TOWARD SUNRISE. VFR CONDITIONS
WILL RETURN BY MID MORNING. INSTABILITY WILL BRING CHANCE OF
THUNDERSTORMS AGAIN THURSDAY AFTERNOON TO BOTH SITES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...FS
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1032 PM EDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 1032 PM EDT FRI MAY 23 2014
TEMPERATURES ALREADY DOWN INTO THE LOW TO MID 50S IN THE LAST HOUR
AND ON TRACK FOR MID 40S IN THE COLDEST VALLEYS. FORECAST IS ON TRACK
WITH TEMPERATURES...SO NO NEED FOR ANY UPDATES AT THIS TIME.
UPDATE ISSUED AT 704 PM EDT FRI MAY 23 2014
WITH DEWPOINTS MIXING INTO THE MID 40S THIS AFTERNOON..OPTED TO TAKE
LOWS IN THE COLDER VALLEYS DOWN A FEW DEGREES. OTHERWISE...FORECAST
IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 350 PM EDT FRI MAY 23 2014
18Z SFC ANALYSIS SHOWS CANADIAN HIGH PRESSURE DROPPING INTO THE OHIO
VALLEY TODAY BRINGING ITS DRIER AIR MASS AND COOLER TEMPS. THIS HAS
MADE FOR A PLEASANT AND COMFORTABLE DAY FOR MUCH OF EAST KENTUCKY
UNDER PARTLY TO MOSTLY SUNNY SKIES. JUST ALONG THE BORDER WITH
TENNESSEE A FEW SPRINKLES MAY OCCUR AND CONDITIONS WILL BE MORE
HUMID...AS A COLD FRONT SETTLES INTO THE SOUTH PARTS OF THE STATE.
DIFFERENCES BROUGHT BY THIS FRONT TO EAST KENTUCKY INCLUDE TEMPS
ONLY IN THE LOWER 70S ACROSS THE NORTH ALONG WITH DEWPOINTS IN THE
40S WHILE TO THE FAR SOUTH READINGS ARE IN THE MID AND UPPER 70S AND
DEWPOINTS CLOSER TO 60. NORTH TO NORTHWEST WINDS GENERALLY AT 5 TO 10
MPH...WITH SOME GUSTS TO 15 MPH...ARE FOUND THROUGH THE AREA AT THIS
TIME.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT AS THEY ALL DEPICT THE SLOW
EVOLUTION OF THE RIDGE AND TROUGH STRUCTURE THROUGH THE AREA. A
RELATIVELY SHARP TROUGH WILL SWEEP BY WELL TO THE NORTHEAST TONIGHT
ALLOWING HEIGHTS TO REBOUND INTO SATURDAY AS RIDGING EASES INTO THE
STATE FROM THE SOUTHWEST. THIS WILL ALSO PUSH THE TRACK OF ANY MINOR
MID LEVEL WAVES TO THE EAST OF THE AREA KEEPING THE FLOW PATTERN
RATHER SMOOTH OVER EAST KENTUCKY INTO SUNDAY MORNING. ON ACCOUNT OF
THE SIMILARITIES IN THE MODELS HAVE LEANED TOWARD THE LATEST RUNS OF
THE HRRR AND NAM12 FOR WEATHER SPECIFICS.
SENSIBLE WEATHER WILL FEATURE A COOLER NIGHT UNDER MOSTLY CLEAR
SKIES WITH THE FRONT OFF TO THE SOUTHWEST. A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT IS EXPECTED TO OPEN UP DURING THE EVENING AND
CONTINUE THROUGH THE NIGHT. PATCHY FOG WILL BE POSSIBLE IN THE
VALLEYS LATER TONIGHT AND INTO THE FIRST PART OF SATURDAY MORNING.
VERY PLEASANT WEATHER CAN BE EXPECTED ON SATURDAY AS COMFORTABLE
HUMIDITY LEVELS WILL CONTINUE ALONG WITH PLENTY OF SUNSHINE AND
TEMPERATURES TOPPING OUT IN THE MID TO UPPER 70S. SIMILAR CONDITIONS
TO TONIGHT/S WILL BE HAD SATURDAY NIGHT...THOUGH SFC HIGH PRESSURE
MOVING BY TO THE NORTH SHOULD YIELD MORE OF A RIDGE TO VALLEY
TEMPERATURE SPLIT BY SUNDAY MORNING THAN WE ANTICIPATE FOR TONIGHT.
AFTER AN EXTRA DAY FOR THE BOUNDARY LAYER TO DRY OUT...THE PATCHY FOG
SHOULD BE CONFINED TO MAINLY THE DEEPEST VALLEYS JUST AROUND DAWN
SUNDAY MORNING.
AGAIN USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPS...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
FILLING THE GAP TO THE END OF THE SHORT TERM. MOST OF THE ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES IN THE LOWS TONIGHT AND
A BIT MORE EXTENSIVELY ON SATURDAY NIGHT. AS FOR POPS...ENDED UP IN
LINE WITH THE MOS NUMBERS THROUGH SUNDAY MORNING HOLDING IN THE LOW
SINGLE DIGITS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 400 PM EDT FRI MAY 23 2014
FORECAST STILL SEEMS TO BE IN GOOD AGREEMENT FROM YESTERDAY TO
TODAY. AT 12Z SUNDAY...STRONG UPPER LEVEL RIDGING WILL BE MOVING
INTO THE OHIO VALLEY REGION...WITH A CLOSED LOW REMAINING STEADY
OVER THE SOUTHERN PLAINS DURING MUCH OF THE MID TERM. ANOTHER TROUGH
WILL FORM OVER THE NORTHEAST CONUS...WITH SEVERAL CLOSED WAVES
MOVING THROUGH OVER THE COURSE OF THE EXTENDED PERIOD. WITH THESE
TWO TROUGHS IN PLACE...EXPECT THE UPPER LEVEL RIDGE TO REMAIN THE
DRIVING FORCE THROUGH MUCH OF THE EXTENDED.
THE 300MB JET STREAM WILL REMAIN WELL TO OUR NORTH...PLAYING INTO
THE NEW ENGLAND TROUGHING DURING THE EXTENDED. MEANWHILE...WEAK FLOW
ACROSS THE OHIO VALLEY...AND SOUTHERN RIDGING...WILL MEAN WELL ABOVE
NORMAL TEMPS FOR KY INTO THE FIRST HALF OF THE WEEK. FOR MONDAY AND
TUESDAY...THERE WILL BE ENOUGH MOISTURE FLOW AND AFTERNOON
INSTABILITY THAT SOME DIURNAL ISOLATED /MONDAY/ TO LOW END SCATTERED
/TUESDAY/ SHOWER AND THUNDERSTORMS WILL BE POSSIBLE. THE GFS IS THE
MOST AGGRESSIVE WITH BRINGING MOISTURE INTO THE AREA DURING THIS
TIME...WHILE THE GEM AND ECMWF SHOW THE MAIN THREAT FOR PRECIP ON
TUESDAY AND NOT MONDAY. BASED ON THE UNCERTAINTY...AND SCATTERED
NATURE OF THIS SET UP...DECIDED TO STICK CLOSE TO THE ALLBLEND FOR
POPS DURING THIS TIME PERIOD.
BY TUESDAY EVENING...A SURFACE LOW WILL MAKES ITS WAY SE ACROSS THE
NEW ENGLAND STATES. IN DOING SO...IT WILL PUSH A SURFACE COLD FRONT
SOUTHWARD...MAKING IT INTO EASTERN KY IN THE FORM OF A BACK DOOR
FRONT TUESDAY NIGHT AND WEDNESDAY. THE GFS SEEMS TO BRING THE FRONT
THROUGH ABOUT 6 HOURS FASTER THAN THE ECMWF...WITH A BAND OF SHOWERS
AND THUNDERSTORMS PUSHING FROM NE TO SE TUESDAY EVENING THROUGH
WEDNESDAY EVENING. BEHIND THIS FRONT...SOMEWHAT DRIER AIR WILL
FILTER IN...ALONG WITH A SLIGHT COOL DOWN IN TEMPERATURES FOR
WEDNESDAY. NEITHER ONE WILL BE SIGNIFICANT. ONCE AGAIN...GIVEN THE
UNCERTAINTY BETWEEN THE TWO MODELS THIS FAR OUT...STUCK FAIRLY CLOSE
TO THE ALLBLEND SOLUTION FOR POPS.
ONCE THE FRONT MOVES THROUGH...THE SURFACE LOW WILL THEN SHIFT BACK
NORTHWARD. THIS COULD ALLOW THE OPPORTUNITY FOR THE FRONT...THOUGH
WEEK...TO PUSH BACK NORTHWARD INTO KY AS WELL LATE IN THE WEEK. THIS
COULD POSSIBLY PUSH MOISTURE BACK INTO THE CWA FOR
THURSDAY...FRIDAY...AND POINTS AFTER. UNCERTAINTY THIS FAR OUT DOES
NOT WARRANT ANY MORE THAN CHANCE POPS. DAYTIME HEATING WILL HELP TO
INITIATE ANY SHOWERS/TSTORMS...SO EXPECT BEST CHANCE POPS DURING THE
AFTERNOON/EVENING HOURS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 704 PM EDT FRI MAY 23 2014
MAINLY VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 TO 36 HOURS. SOME
PATCHY MVFR FOG COULD DEVELOP LATE TONIGHT NEAR THE RIVER BEDS...BUT
SHOULD NOT IMPACT AIRPORTS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
704 PM EDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 704 PM EDT FRI MAY 23 2014
WITH DEWPOINTS MIXING INTO THE MID 40S THIS AFTERNOON..OPTED TO TAKE
LOWS IN THE COLDER VALLEYS DOWN A FEW DEGREES. OTHERWISE...FORECAST
IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 350 PM EDT FRI MAY 23 2014
18Z SFC ANALYSIS SHOWS CANADIAN HIGH PRESSURE DROPPING INTO THE OHIO
VALLEY TODAY BRINGING ITS DRIER AIR MASS AND COOLER TEMPS. THIS HAS
MADE FOR A PLEASANT AND COMFORTABLE DAY FOR MUCH OF EAST KENTUCKY
UNDER PARTLY TO MOSTLY SUNNY SKIES. JUST ALONG THE BORDER WITH
TENNESSEE A FEW SPRINKLES MAY OCCUR AND CONDITIONS WILL BE MORE
HUMID...AS A COLD FRONT SETTLES INTO THE SOUTH PARTS OF THE STATE.
DIFFERENCES BROUGHT BY THIS FRONT TO EAST KENTUCKY INCLUDE TEMPS
ONLY IN THE LOWER 70S ACROSS THE NORTH ALONG WITH DEWPOINTS IN THE
40S WHILE TO THE FAR SOUTH READINGS ARE IN THE MID AND UPPER 70S AND
DEWPOINTS CLOSER TO 60. NORTH TO NORTHWEST WINDS GENERALLY AT 5 TO 10
MPH...WITH SOME GUSTS TO 15 MPH...ARE FOUND THROUGH THE AREA AT THIS
TIME.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT AS THEY ALL DEPICT THE SLOW
EVOLUTION OF THE RIDGE AND TROUGH STRUCTURE THROUGH THE AREA. A
RELATIVELY SHARP TROUGH WILL SWEEP BY WELL TO THE NORTHEAST TONIGHT
ALLOWING HEIGHTS TO REBOUND INTO SATURDAY AS RIDGING EASES INTO THE
STATE FROM THE SOUTHWEST. THIS WILL ALSO PUSH THE TRACK OF ANY MINOR
MID LEVEL WAVES TO THE EAST OF THE AREA KEEPING THE FLOW PATTERN
RATHER SMOOTH OVER EAST KENTUCKY INTO SUNDAY MORNING. ON ACCOUNT OF
THE SIMILARITIES IN THE MODELS HAVE LEANED TOWARD THE LATEST RUNS OF
THE HRRR AND NAM12 FOR WEATHER SPECIFICS.
SENSIBLE WEATHER WILL FEATURE A COOLER NIGHT UNDER MOSTLY CLEAR
SKIES WITH THE FRONT OFF TO THE SOUTHWEST. A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT IS EXPECTED TO OPEN UP DURING THE EVENING AND
CONTINUE THROUGH THE NIGHT. PATCHY FOG WILL BE POSSIBLE IN THE
VALLEYS LATER TONIGHT AND INTO THE FIRST PART OF SATURDAY MORNING.
VERY PLEASANT WEATHER CAN BE EXPECTED ON SATURDAY AS COMFORTABLE
HUMIDITY LEVELS WILL CONTINUE ALONG WITH PLENTY OF SUNSHINE AND
TEMPERATURES TOPPING OUT IN THE MID TO UPPER 70S. SIMILAR CONDITIONS
TO TONIGHT/S WILL BE HAD SATURDAY NIGHT...THOUGH SFC HIGH PRESSURE
MOVING BY TO THE NORTH SHOULD YIELD MORE OF A RIDGE TO VALLEY
TEMPERATURE SPLIT BY SUNDAY MORNING THAN WE ANTICIPATE FOR TONIGHT.
AFTER AN EXTRA DAY FOR THE BOUNDARY LAYER TO DRY OUT...THE PATCHY FOG
SHOULD BE CONFINED TO MAINLY THE DEEPEST VALLEYS JUST AROUND DAWN
SUNDAY MORNING.
AGAIN USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPS...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
FILLING THE GAP TO THE END OF THE SHORT TERM. MOST OF THE ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES IN THE LOWS TONIGHT AND
A BIT MORE EXTENSIVELY ON SATURDAY NIGHT. AS FOR POPS...ENDED UP IN
LINE WITH THE MOS NUMBERS THROUGH SUNDAY MORNING HOLDING IN THE LOW
SINGLE DIGITS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 400 PM EDT FRI MAY 23 2014
FORECAST STILL SEEMS TO BE IN GOOD AGREEMENT FROM YESTERDAY TO
TODAY. AT 12Z SUNDAY...STRONG UPPER LEVEL RIDGING WILL BE MOVING
INTO THE OHIO VALLEY REGION...WITH A CLOSED LOW REMAINING STEADY
OVER THE SOUTHERN PLAINS DURING MUCH OF THE MID TERM. ANOTHER TROUGH
WILL FORM OVER THE NORTHEAST CONUS...WITH SEVERAL CLOSED WAVES
MOVING THROUGH OVER THE COURSE OF THE EXTENDED PERIOD. WITH THESE
TWO TROUGHS IN PLACE...EXPECT THE UPPER LEVEL RIDGE TO REMAIN THE
DRIVING FORCE THROUGH MUCH OF THE EXTENDED.
THE 300MB JET STREAM WILL REMAIN WELL TO OUR NORTH...PLAYING INTO
THE NEW ENGLAND TROUGHING DURING THE EXTENDED. MEANWHILE...WEAK FLOW
ACROSS THE OHIO VALLEY...AND SOUTHERN RIDGING...WILL MEAN WELL ABOVE
NORMAL TEMPS FOR KY INTO THE FIRST HALF OF THE WEEK. FOR MONDAY AND
TUESDAY...THERE WILL BE ENOUGH MOISTURE FLOW AND AFTERNOON
INSTABILITY THAT SOME DIURNAL ISOLATED /MONDAY/ TO LOW END SCATTERED
/TUESDAY/ SHOWER AND THUNDERSTORMS WILL BE POSSIBLE. THE GFS IS THE
MOST AGGRESSIVE WITH BRINGING MOISTURE INTO THE AREA DURING THIS
TIME...WHILE THE GEM AND ECMWF SHOW THE MAIN THREAT FOR PRECIP ON
TUESDAY AND NOT MONDAY. BASED ON THE UNCERTAINTY...AND SCATTERED
NATURE OF THIS SET UP...DECIDED TO STICK CLOSE TO THE ALLBLEND FOR
POPS DURING THIS TIME PERIOD.
BY TUESDAY EVENING...A SURFACE LOW WILL MAKES ITS WAY SE ACROSS THE
NEW ENGLAND STATES. IN DOING SO...IT WILL PUSH A SURFACE COLD FRONT
SOUTHWARD...MAKING IT INTO EASTERN KY IN THE FORM OF A BACK DOOR
FRONT TUESDAY NIGHT AND WEDNESDAY. THE GFS SEEMS TO BRING THE FRONT
THROUGH ABOUT 6 HOURS FASTER THAN THE ECMWF...WITH A BAND OF SHOWERS
AND THUNDERSTORMS PUSHING FROM NE TO SE TUESDAY EVENING THROUGH
WEDNESDAY EVENING. BEHIND THIS FRONT...SOMEWHAT DRIER AIR WILL
FILTER IN...ALONG WITH A SLIGHT COOL DOWN IN TEMPERATURES FOR
WEDNESDAY. NEITHER ONE WILL BE SIGNIFICANT. ONCE AGAIN...GIVEN THE
UNCERTAINTY BETWEEN THE TWO MODELS THIS FAR OUT...STUCK FAIRLY CLOSE
TO THE ALLBLEND SOLUTION FOR POPS.
ONCE THE FRONT MOVES THROUGH...THE SURFACE LOW WILL THEN SHIFT BACK
NORTHWARD. THIS COULD ALLOW THE OPPORTUNITY FOR THE FRONT...THOUGH
WEEK...TO PUSH BACK NORTHWARD INTO KY AS WELL LATE IN THE WEEK. THIS
COULD POSSIBLY PUSH MOISTURE BACK INTO THE CWA FOR
THURSDAY...FRIDAY...AND POINTS AFTER. UNCERTAINTY THIS FAR OUT DOES
NOT WARRANT ANY MORE THAN CHANCE POPS. DAYTIME HEATING WILL HELP TO
INITIATE ANY SHOWERS/TSTORMS...SO EXPECT BEST CHANCE POPS DURING THE
AFTERNOON/EVENING HOURS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 704 PM EDT FRI MAY 23 2014
MAINLY VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 TO 36 HOURS. SOME
PATCHY MVFR FOG COULD DEVELOP LATE TONIGHT NEAR THE RIVER BEDS...BUT
SHOULD NOT IMPACT AIRPORTS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...KAS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
635 PM EDT THU MAY 22 2014
.UPDATE...
ISSUED AT 635 PM EDT THU MAY 22 2014
WITH THE WORST OF THE STORMS SINKING SOUTH OUT OF EAST KENTUCKY HAVE
GONE AHEAD AND DROPPED THE SEVERE WATCH FOR WAYNE AND MCCREARY
COUNTIES. ALSO TAPERED OFF THE THUNDERSTORM CHANCES THROUGH THE REST
OF THE EVENING AND ADDED SOME PATCHY DENSE FOG TO THE VALLEYS LATE
TONIGHT. FINALLY...TWEAKED THE NEAR TERM GRIDS PER THE LATEST OBS AND
TRENDS. THESE GRID UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS
ALONG WITH THE DISSEMINATION OF THE ZFP AND WCN. AN UPDATED HWO IS IN
THE QUEUE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 415 PM EDT THU MAY 22 2014
19Z SFC ANALYSIS SHOWS LOW PRESSURE CENTERED OVER THE POCONOS WITH A
COLD FRONT STRETCHED SOUTHWEST AND BISECTING KENTUCKY. SOUTH OF THIS
FRONT DEWPOINTS ARE IN THE MID AND UPPER 60S WITH TEMPERATURES IN THE
MID 80S. CONDITIONS ARE JUST A BIT DRIER AND COOLER TO THE NORTHWEST
OF IT. TO THE SOUTH OF THE FRONT...INSTABILITY IS QUITE HIGH WITH
LIS IN THE -8 TO -10 DEGREE RANGE WITH CAPE TO 3500 J/KG OVER THE
WESTERN PORTION OF THE STATE. ON SATELLITE...THE CU IS DOING BEST
OVER SOUTHERN KENTUCKY...WHILE ON RADAR SOME RETURNS ARE FINALLY
SHOWING UP TO THE NORTHWEST OF BOWLING GREEN. EXPECT THESE TO DEVELOP
AND STRENGTHEN RAPIDLY WITH A GENERAL MOVEMENT TO THE EAST SOUTHEAST.
SPC HAS HIGHLIGHTED THIS AREA THROUGH SOUTHERN PARTS OF EAST KENTUCKY
FOR A POTENTIAL WATCH BOX. MEANWHILE...WINDS ARE MAINLY FROM THE WEST
AT 10 TO 20 KTS ACROSS EAST KENTUCKY.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE FAST NORTHWEST FLOW
THROUGH NORTHEAST KENTUCKY BETWEEN A RETREATING RIDGE TO THE SOUTH
AND EXPANDING TROUGHING TO THE NORTH. A WEAK PATCH OF ENERGY WILL
PASS THROUGH THIS NORTHWEST FLOW KNOCKING DOWN HEIGHTS LOCALLY INTO
THE EVENING. THE RIDGE IS FURTHER SUPPRESSED ON FRIDAY IN RESPONSE TO
THE NORTHEAST TROUGH DIGGING THROUGH THE CENTRAL APPALACHIANS. ONCE
THIS TROUGH AND SHARP SHORTWAVE MOVES OUT OF THE AREA...HEIGHTS WILL
REBOUND OVER EAST KENTUCKY INTO SATURDAY MORNING. WITH THE GOOD MODEL
AGREEMENT WILL FOLLOW THE DETAILS FROM THE NAM12 AND THE LAST FEW
RUNS OF THE HRRR MOST PROMINENTLY.
SENSIBLE WEATHER WILL FEATURE SCATTERED STORMS OVER THE SOUTHERN
HALF OF THE CWA THIS EVENING...POTENTIALLY SEVERE ALONG THE TENNESSEE
BORDER. A WATCH BOX IS NOW OUT WITH WAYNE AND MCCREARY INCLUDED...AND
JUST IN TIME AS THE STORMS ARE QUICKLY DEVELOPING OVER OUR SOUTHERN
TIER. EXPECT THESE TO FADE OUT BY MIDNIGHT WITH SOME CLEARING HELPING
TO BUILD FOG THROUGH THE VALLEYS ACROSS EAST KENTUCKY. THE FOG COULD
BECOME LOCALLY DENSE IN THE DEEPEST VALLEYS. THE FRONT DRIFTS TO THE
SOUTH OF THE AREA ON FRIDAY TAKING THE THREAT OF SHOWERS AND
THUNDERSTORMS WITH IT. THIS SHOULD MAKE FOR A PLEASANT END TO THE
WORK WEEK WITH TEMPERATURES ABOUT 5 TO 10 DEGREES COOLER THAN TODAY.
LATER FRIDAY NIGHT...ANTICIPATE A DECENT RIDGE TO VALLEY TEMPERATURE
SPLIT GIVEN MOSTLY CLEAR SKIES AND HIGH PRESSURE MOVING BY TO THE
NORTH. SOME PATCHY VALLEY FOG CAN ALSO BE EXPECTED TO DEVELOP
TOWARDS DAWN SATURDAY.
USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
ADDED TO THE END OF THE SHORT TERM THEREAFTER. MOST ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES TONIGHT AND FRIDAY
NIGHT IN THE LOWS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL
GUIDANCE TONIGHT AND THEN SINGLE DIGITS THROUGH THE REST OF THE
PERIOD...IN LINE WITH THE MOS NUMBERS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 PM EDT THU MAY 22 2014
CONDITIONS WILL STAY FAIRLY CONSTANT IN THE UPPER LEVELS DURING THE
EXTENDED...WITH THE MODELS IN FAIRLY GOOD AGREEMENT THROUGH DAY 7.
SATURDAY 12Z WILL START OFF THE PERIOD WITH AN UPPER LEVEL RIDGE
MOVING FROM THE CENTRAL PLAINS ACROSS EASTERN KY. THIS RIDGE WILL
REMAIN THE DRIVING FORCE THROUGH TUESDAY. FOR THE MID TERM SECTION
OF THE FORECAST PERIOD...ANY MOISTURE WILL REMAIN TO THE WEST OF THE
RIDGE...KEEPING MUCH OF KY BOTH DRY AND IN A SOUTHERLY WIND PATTERN.
THIS WILL ALLOW TEMPERATURES TO BOOST TO WELL ABOVE NORMAL THROUGH
EARLY NEXT WEEK. SATURDAY IS STILL EXPECTED TO BE THE COOLEST DAY AS
HIGH PRESSURE AND UPPER LEVEL RIDGING ARE JUST BEGINNING TO TAKE
CONTROL...WITH HIGHS NEAR CLIMATOLOGICAL NORMAL FOR THIS TIME OF
YEAR. TEMPERATURES SATURDAY NIGHT WILL SHOW A DECENT DIURNAL RANGE
WITH A THERMAL BELT SETTING UP AROUND THE RIDGES. THEN AS SOUTHERLY
FLOW TAKES CONTROL...TEMPS WILL BEGIN TO RISE INTO THE MID AND EVEN
SOME UPPER 80S BY TUESDAY OF NEXT WEEK.
MODELS ARE SHOWING SOME VARIATION IN SOME ISOLATED TO SCATTERED
AFTERNOON SHOWERS/TSTORMS FOR MONDAY AND TUESDAY
AFTERNOON...ALTHOUGH NO PARTICULAR MODEL IS GOING TO HAVE A GOOD
HANDLE WHERE THEY WILL SET UP EXACTLY. THERE IS ENOUGH EVIDENCE TO
WARRANT ISOLATED CHANCES ON MONDAY...AND SCATTERED CHANCES ACROSS
EASTERN KY FOR TUESDAY. BY TUESDAY EVENING...LOW PRESSURE OVER THE
SOUTH CENTRAL PLAINS WILL HAVE SHIFTED EASTWARD SLIGHTLY AND WILL BE
ENTERING INTO THE MISSISSIPPI RIVER VALLEY. THIS WILL CREATE MORE
LIFT AND MOISTURE INFLUX...AS WELL AS CONTINUED WARM UNSTABLE
AIR...ALLOWING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO CONTINUE
TUESDAY NIGHT INTO THURSDAY TO ROUND OUT OUR FORECAST PERIOD. STUCK
PRETTY CLOSE TO THE ALLBLEND FOR THE EXTENDED POPS DUE TO THE
UNCERTAINTY IN CONVECTION THIS FAR OUT IN THE FORECAST PERIOD.
SMOOTHED OUT ANY MAJOR BULLSEYES OF POPS AND LOWERED SOME OF THE
HIGHER END CHANCES THAT ARE HARD TO WARRANT THIS FAR OUT.
OTHERWISE...WE ARE MATCHING UP QUITE WELL WITH SURROUNDING OFFICES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 215 PM EDT THU MAY 22 2014
HAVE SPLIT THE TAFS FOR A STORM THREAT THIS AFTERNOON AND INTO THE
EARLY EVENING WITH JKL AND SJS LEFT OUT. GIVEN THE UNCERTAINTY HAVE
KEPT THIS JUST AS A VCTS MENTION FOR SME AND LOZ THROUGH 23Z. THE
GROUND MOISTURE LEFT BEHIND FROM THE STORMS LAST NIGHT AND ANY THE
TAKE SHAPE LATER THIS AFTERNOON WILL LIKELY BE ENOUGH FOR AREAS OF
FOG...LOCALLY DENSE IN SOME OF THE DEEPER VALLEYS...AND LIFR AT SME
AND LOZ...AS SKIES GO AT LEAST PARTIALLY CLEAR TONIGHT. THE FOG WILL
CLEAR OUT BY MID MORNING ON FRIDAY WITH ANY CLOUDS DEVELOPING LIKELY
STAYING VFR. WINDS WILL BE BREEZY FROM THE WEST SOUTHWEST THIS
AFTERNOON WITH SPEEDS OF 10 TO 20 KTS BEFORE SETTLING DOWN INTO
SINGLE DIGITS FROM THE NORTHWEST LATER TONIGHT...CONTINUING INTO THE
DAY FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
415 PM EDT THU MAY 22 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 415 PM EDT THU MAY 22 2014
19Z SFC ANALYSIS SHOWS LOW PRESSURE CENTERED OVER THE POCONOS WITH A
COLD FRONT STRETCHED SOUTHWEST AND BISECTING KENTUCKY. SOUTH OF THIS
FRONT DEWPOINTS ARE IN THE MID AND UPPER 60S WITH TEMPERATURES IN THE
MID 80S. CONDITIONS ARE JUST A BIT DRIER AND COOLER TO THE NORTHWEST
OF IT. TO THE SOUTH OF THE FRONT...INSTABILITY IS QUITE HIGH WITH
LIS IN THE -8 TO -10 DEGREE RANGE WITH CAPE TO 3500 J/KG OVER THE
WESTERN PORTION OF THE STATE. ON SATELLITE...THE CU IS DOING BEST
OVER SOUTHERN KENTUCKY...WHILE ON RADAR SOME RETURNS ARE FINALLY
SHOWING UP TO THE NORTHWEST OF BOWLING GREEN. EXPECT THESE TO DEVELOP
AND STRENGTHEN RAPIDLY WITH A GENERAL MOVEMENT TO THE EAST SOUTHEAST.
SPC HAS HIGHLIGHTED THIS AREA THROUGH SOUTHERN PARTS OF EAST KENTUCKY
FOR A POTENTIAL WATCH BOX. MEANWHILE...WINDS ARE MAINLY FROM THE WEST
AT 10 TO 20 KTS ACROSS EAST KENTUCKY.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE FAST NORTHWEST FLOW
THROUGH NORTHEAST KENTUCKY BETWEEN A RETREATING RIDGE TO THE SOUTH
AND EXPANDING TROUGHING TO THE NORTH. A WEAK PATCH OF ENERGY WILL
PASS THROUGH THIS NORTHWEST FLOW KNOCKING DOWN HEIGHTS LOCALLY INTO
THE EVENING. THE RIDGE IS FURTHER SUPPRESSED ON FRIDAY IN RESPONSE TO
THE NORTHEAST TROUGH DIGGING THROUGH THE CENTRAL APPALACHIANS. ONCE
THIS TROUGH AND SHARP SHORTWAVE MOVES OUT OF THE AREA...HEIGHTS WILL
REBOUND OVER EAST KENTUCKY INTO SATURDAY MORNING. WITH THE GOOD MODEL
AGREEMENT WILL FOLLOW THE DETAILS FROM THE NAM12 AND THE LAST FEW
RUNS OF THE HRRR MOST PROMINENTLY.
SENSIBLE WEATHER WILL FEATURE SCATTERED STORMS OVER THE SOUTHERN
HALF OF THE CWA THIS EVENING...POTENTIALLY SEVERE ALONG THE TENNESSEE
BORDER. A WATCH BOX IS NOW OUT WITH WAYNE AND MCCREARY INCLUDED...AND
JUST IN TIME AS THE STORMS ARE QUICKLY DEVELOPING OVER OUR SOUTHERN
TIER. EXPECT THESE TO FADE OUT BY MIDNIGHT WITH SOME CLEARING HELPING
TO BUILD FOG THROUGH THE VALLEYS ACROSS EAST KENTUCKY. THE FOG COULD
BECOME LOCALLY DENSE IN THE DEEPEST VALLEYS. THE FRONT DRIFTS TO THE
SOUTH OF THE AREA ON FRIDAY TAKING THE THREAT OF SHOWERS AND
THUNDERSTORMS WITH IT. THIS SHOULD MAKE FOR A PLEASANT END TO THE
WORK WEEK WITH TEMPERATURES ABOUT 5 TO 10 DEGREES COOLER THAN TODAY.
LATER FRIDAY NIGHT...ANTICIPATE A DECENT RIDGE TO VALLEY TEMPERATURE
SPLIT GIVEN MOSTLY CLEAR SKIES AND HIGH PRESSURE MOVING BY TO THE
NORTH. SOME PATCHY VALLEY FOG CAN ALSO BE EXPECTED TO DEVELOP
TOWARDS DAWN SATURDAY.
USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
ADDED TO THE END OF THE SHORT TERM THEREAFTER. MOST ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES TONIGHT AND FRIDAY
NIGHT IN THE LOWS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL
GUIDANCE TONIGHT AND THEN SINGLE DIGITS THROUGH THE REST OF THE
PERIOD...IN LINE WITH THE MOS NUMBERS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 PM EDT THU MAY 22 2014
CONDITIONS WILL STAY FAIRLY CONSTANT IN THE UPPER LEVELS DURING THE
EXTENDED...WITH THE MODELS IN FAIRLY GOOD AGREEMENT THROUGH DAY 7.
SATURDAY 12Z WILL START OFF THE PERIOD WITH AN UPPER LEVEL RIDGE
MOVING FROM THE CENTRAL PLAINS ACROSS EASTERN KY. THIS RIDGE WILL
REMAIN THE DRIVING FORCE THROUGH TUESDAY. FOR THE MID TERM SECTION
OF THE FORECAST PERIOD...ANY MOISTURE WILL REMAIN TO THE WEST OF THE
RIDGE...KEEPING MUCH OF KY BOTH DRY AND IN A SOUTHERLY WIND PATTERN.
THIS WILL ALLOW TEMPERATURES TO BOOST TO WELL ABOVE NORMAL THROUGH
EARLY NEXT WEEK. SATURDAY IS STILL EXPECTED TO BE THE COOLEST DAY AS
HIGH PRESSURE AND UPPER LEVEL RIDGING ARE JUST BEGINNING TO TAKE
CONTROL...WITH HIGHS NEAR CLIMATOLOGICAL NORMAL FOR THIS TIME OF
YEAR. TEMPERATURES SATURDAY NIGHT WILL SHOW A DECENT DIURNAL RANGE
WITH A THERMAL BELT SETTING UP AROUND THE RIDGES. THEN AS SOUTHERLY
FLOW TAKES CONTROL...TEMPS WILL BEGIN TO RISE INTO THE MID AND EVEN
SOME UPPER 80S BY TUESDAY OF NEXT WEEK.
MODELS ARE SHOWING SOME VARIATION IN SOME ISOLATED TO SCATTERED
AFTERNOON SHOWERS/TSTORMS FOR MONDAY AND TUESDAY
AFTERNOON...ALTHOUGH NO PARTICULAR MODEL IS GOING TO HAVE A GOOD
HANDLE WHERE THEY WILL SET UP EXACTLY. THERE IS ENOUGH EVIDENCE TO
WARRANT ISOLATED CHANCES ON MONDAY...AND SCATTERED CHANCES ACROSS
EASTERN KY FOR TUESDAY. BY TUESDAY EVENING...LOW PRESSURE OVER THE
SOUTH CENTRAL PLAINS WILL HAVE SHIFTED EASTWARD SLIGHTLY AND WILL BE
ENTERING INTO THE MISSISSIPPI RIVER VALLEY. THIS WILL CREATE MORE
LIFT AND MOISTURE INFLUX...AS WELL AS CONTINUED WARM UNSTABLE
AIR...ALLOWING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO CONTINUE
TUESDAY NIGHT INTO THURSDAY TO ROUND OUT OUR FORECAST PERIOD. STUCK
PRETTY CLOSE TO THE ALLBLEND FOR THE EXTENDED POPS DUE TO THE
UNCERTAINTY IN CONVECTION THIS FAR OUT IN THE FORECAST PERIOD.
SMOOTHED OUT ANY MAJOR BULLSEYES OF POPS AND LOWERED SOME OF THE
HIGHER END CHANCES THAT ARE HARD TO WARRANT THIS FAR OUT.
OTHERWISE...WE ARE MATCHING UP QUITE WELL WITH SURROUNDING OFFICES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 215 PM EDT THU MAY 22 2014
HAVE SPLIT THE TAFS FOR A STORM THREAT THIS AFTERNOON AND INTO THE
EARLY EVENING WITH JKL AND SJS LEFT OUT. GIVEN THE UNCERTAINTY HAVE
KEPT THIS JUST AS A VCTS MENTION FOR SME AND LOZ THROUGH 23Z. THE
GROUND MOISTURE LEFT BEHIND FROM THE STORMS LAST NIGHT AND ANY THE
TAKE SHAPE LATER THIS AFTERNOON WILL LIKELY BE ENOUGH FOR AREAS OF
FOG...LOCALLY DENSE IN SOME OF THE DEEPER VALLEYS...AND LIFR AT SME
AND LOZ...AS SKIES GO AT LEAST PARTIALLY CLEAR TONIGHT. THE FOG WILL
CLEAR OUT BY MID MORNING ON FRIDAY WITH ANY CLOUDS DEVELOPING LIKELY
STAYING VFR. WINDS WILL BE BREEZY FROM THE WEST SOUTHWEST THIS
AFTERNOON WITH SPEEDS OF 10 TO 20 KTS BEFORE SETTLING DOWN INTO
SINGLE DIGITS FROM THE NORTHWEST LATER TONIGHT...CONTINUING INTO THE
DAY FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
215 PM EDT THU MAY 22 2014
.UPDATE...
ISSUED AT 200 PM EDT THU MAY 22 2014
WATCHING FOR CONVECTIVE DEVELOPMENT OVER WESTERN KENTUCKY WHERE THE
NAM12 AND HRRR SUGGEST THAT AN MCS MAY BE SPAWNED THIS AFTERNOON. IN
THIS LOCATION...DEWPOINTS ARE IN THE LOWER 70S WITH TEMPS
APPROACHING THE MID 80S. THIS RESULTS IN CAPE AND LIS THAT ARE QUITE
SUPPORTIVE OF STRONG TO SEVERE STORMS. HOWEVER...DESPITE THE
BOUNDARY FROM THE EARLIER STORMS CUTTING THROUGH THE UNSTABLE AIR...
THE RADARS HAVE REMAINED CLEAN. THERE IS SOME CU FORMING ACROSS THE
SOUTHERN PORTION OF THE STATE BUT THE DEPTH OF THESE IS NOT TOO
IMPRESSIVE...AS OF YET. HAVE UPDATED THE FORECAST THROUGH 00Z TO
HONE IN ON THE THREAT OF STORMS ACROSS OUR SOUTH. ALSO FINE TUNED THE
SKY/T/TD GRIDS TO REFLECT THE LATEST OBS AND TRENDS. THESE HAVE BEEN
SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 1040 AM EDT THU MAY 22 2014
14Z SFC ANALYSIS SHOWS LOW PRESSURE HAS NOW MOVED TO OVER UPSTATE NEW
YORK WHILE ITS COLD FRONT STRETCHES SOUTHWEST THROUGH KENTUCKY.
EARLIER CONVECTION HAS PUSHED SOUTH OF EAST KENTUCKY...BUT ALSO LEFT
BEHIND AN OUTFLOW BOUNDARY THAT COULD BECOME SIGNIFICANT WITH DAYTIME
HEATING AND INSTABILITY. THE HRRR AND NAM12 KEEP MOST OF THE
REDEVELOPMENT SOUTH AND EAST OF OUR AREA LATER TODAY...BUT WITH THAT
BOUNDARY IN PLACE AND THE HISTORY OF THIS SYSTEM SEVERE WEATHER WILL
REMAIN A POSSIBILITY OVER FAR SOUTHERN PARTS OF THE CWA. FOR NOW...
THOUGH...IN THE WAKE OF THE EARLY MORNING STORMS A LULL WILL SET IN
FOR THE BULK OF EAST KENTUCKY. IN FACT...A PLEASANT DAY WILL BE HAD
FOR MOST WITH PARTLY SUNNY SKIES AND ANY STORMS STAYING TO THE SOUTH.
HOWEVER...THOSE SOUTHERN LOCALES...GENERALLY FROM THE HAL ROGERS
PARKWAY TO THE TENNESSEE BORDER...WILL HAVE TO BE ON THE LOOK OUT FOR
STORMS LATER THIS AFTERNOON AND SOME OF THESE COULD BE QUITE STRONG
WITH LARGE HAIL AND DAMAGING WIND GUSTS THE MAIN THREATS. HAVE
UPDATED THE GRIDS...ZONES...AND HWO TO REFLECT THESE EXPECTATIONS AND
ALSO INCORPORATED THE LATEST GUIDANCE...OBS...AND TRENDS INTO THE T
AND TD GRIDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 345 AM EDT THU MAY 22 2014
MODELS HAVE BEEN HAVING A DIFFICULT TIME RESOLVING THE CLUSTERS OF
THUNDERSTORMS THAT HAVE BEEN PLAGUING THE AREA SINCE LATE WEDNESDAY
EVENING. THE FORECAST FROM 6Z THROUGH NOW WERE UPDATED MOSTLY USING
THE LATEST TRENDS OBSERVED IN RADAR AND SATELLITE IMAGERY. CURRENT
ACTIVITY HAS BEEN SHOWING A STEADY WEAKENING TREND OVER THE PAST HOUR
OR SO. ALL INDICATIONS ARE THAT ANY REMAINING THUNDERSTORMS WILL
PRODUCE MINIMAL WIND GUSTS AND ISOLATED INSTANCES OF LOCALLY HEAVY
RAINFALL THROUGH THE REMAINDER OF THE OVERNIGHT. MORE STORMS CONTINUE
TO FORM IN A PREFERRED AREA OF LIFT AND MOISTURE CONVERGENCE ACROSS
SOUTHERN INDIANA AND WILL LIKELY CONTINUE TO MOVE ACROSS CENTRAL AND
EASTERN KENTUCKY THROUGH EARLY THIS MORNING. THE MODELS ARE
INDICATING THAT THERE WILL BE BRIEF LULL IN ACTIVITY IN THE
MORNING...BEFORE THINGS RAMP BACK UP A BIT DURING THE AFTERNOON HOURS
AS A COLD FRONT SAGS SLOWLY SOUTHWARD ACROSS THE REGION OUT OF THE
OHIO VALLEY. THE MODEL CONSENSUS SAYS THAT THE LAST SHOWERS AND
STORMS WILL BE OUT OF THE AREA AROUND 5Z FRIDAY. THERE IS A SLIGHT
RISK THAT A FEW STORMS COULD APPROACH SEVERE LIMITS ALONG AND JUST
NORTH OF THE TENNESSEE BORDER TODAY...AS THIS WAS MENTIONED IN THE
HAZARDOUS WEATHER OUTLOOK EVEN THOUGH CONFIDENCE IS NOT HIGH THAT
THIS WILL OCCUR. STRONG WINDS AND LARGE HAIL WOULD BE THE PRIMARY
THREATS WITH ANY STORMS THAT REACH SEVERE STATUS. THE WEATHER FOR
THURSDAY NIGHT AND FRIDAY WILL DRY AND SLIGHTLY COOLER AS ANOTHER
RIDGE OF HIGH PRESSURE SETTLES OVER THE AREA.
TEMPERATURES TODAY WILL BE RUNNING ABOVE NORMAL ONCE AGAIN WITH
READINGS EXPECTED TO TOP OUT AROUND 80 DEGREES ACROSS THE AREA AS THE
AIR MASS BEHIND THE COLD FRONT QUICKLY MODIFIES. THE FRONT ITSELF IS
NOT ALL THAT WELL DEFINED SO THE AIR BEHIND IT WILL PROBABLY NOT COOL
THINGS OFF VERY MUCH ONCE THE FRONT HAS PASSED. IN SPITE OF THE
SLIGHTLY COOLER AIR MASS...TEMPERATURES ON FRIDAY SHOULD STILL BE
ABLE TO TOP OUT IN THE UPPER 70S ACROSS THE BOARD.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU MAY 22 2014
THE MODELS IN THE LONG TERM START OUT IN VERY GOOD AGREEMENT WITH A
CUT OFF UPPER LOW OVER ARIZONA...UPPER RIDGING OVER THE PLAINS AND
AN UPPER TROUGH OVER THE EAST COAST. AT THE SURFACE HIGH PRESSURE IS
DOMINATING THE AREA. THE UPPER LOW OVER ARIZONA TRACKS SLOWLY TO THE
NORTHEAST OVER TIME AS THE RIDGE AXIS MOVE SLOWLY TO THE EAST AND
WILL BE LOCATED OVER THE MISSISSIPPI VALLEY BY SATURDAY EVENING. BY
TUESDAY AFTERNOON...SOME AFTERNOON AIR MASS THUNDERSTORMS MAY BE
POSSIBLE AS THE UPPER LOW APPROACHES THE AREA. BY THIS TIME THE
MODELS ARE STARTING TO DIVERGE AND CONFIDENCE PLUMMETS. ISOLATED TO
SCATTERED THUNDERSTORMS WILL BE POSSIBLE THROUGH THE END OF THE
PERIOD. FOR TEMPERATURES...STAYED CLOSE TO THE MODEL BLEND...HOWEVER
NUDGED THEM TOWARD THE RAW ECMWF AND MADE CORRECTIONS DUE TO
TERRAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 215 PM EDT THU MAY 22 2014
HAVE SPLIT THE TAFS FOR A STORM THREAT THIS AFTERNOON AND INTO THE
EARLY EVENING WITH JKL AND SJS LEFT OUT. GIVEN THE UNCERTAINTY HAVE
KEPT THIS JUST AS A VCTS MENTION FOR SME AND LOZ THROUGH 23Z. THE
GROUND MOISTURE LEFT BEHIND FROM THE STORMS LAST NIGHT AND ANY THE
TAKE SHAPE LATER THIS AFTERNOON WILL LIKELY BE ENOUGH FOR AREAS OF
FOG...LOCALLY DENSE IN SOME OF THE DEEPER VALLEYS...AND LIFR AT SME
AND LOZ...AS SKIES GO AT LEAST PARTIALLY CLEAR TONIGHT. THE FOG WILL
CLEAR OUT BY MID MORNING ON FRIDAY WITH ANY CLOUDS DEVELOPING LIKELY
STAYING VFR. WINDS WILL BE BREEZY FROM THE WEST SOUTHWEST THIS
AFTERNOON WITH SPEEDS OF 10 TO 20 KTS BEFORE SETTLING DOWN INTO
SINGLE DIGITS FROM THE NORTHWEST LATER TONIGHT...CONTINUING INTO THE
DAY FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...AR
LONG TERM...JJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1040 AM EDT THU MAY 22 2014
.UPDATE...
ISSUED AT 1040 AM EDT THU MAY 22 2014
14Z SFC ANALYSIS SHOWS LOW PRESSURE HAS NOW MOVED TO OVER UPSTATE NEW
YORK WHILE ITS COLD FRONT STRETCHES SOUTHWEST THROUGH KENTUCKY.
EARLIER CONVECTION HAS PUSHED SOUTH OF EAST KENTUCKY...BUT ALSO LEFT
BEHIND AN OUTFLOW BOUNDARY THAT COULD BECOME SIGNIFICANT WITH DAYTIME
HEATING AND INSTABILITY. THE HRRR AND NAM12 KEEP MOST OF THE
REDEVELOPMENT SOUTH AND EAST OF OUR AREA LATER TODAY...BUT WITH THAT
BOUNDARY IN PLACE AND THE HISTORY OF THIS SYSTEM SEVERE WEATHER WILL
REMAIN A POSSIBILITY OVER FAR SOUTHERN PARTS OF THE CWA. FOR NOW...
THOUGH...IN THE WAKE OF THE EARLY MORNING STORMS A LULL WILL SET IN
FOR THE BULK OF EAST KENTUCKY. IN FACT...A PLEASANT DAY WILL BE HAD
FOR MOST WITH PARTLY SUNNY SKIES AND ANY STORMS STAYING TO THE SOUTH.
HOWEVER...THOSE SOUTHERN LOCALES...GENERALLY FROM THE HAL ROGERS
PARKWAY TO THE TENNESSEE BORDER...WILL HAVE TO BE ON THE LOOK OUT FOR
STORMS LATER THIS AFTERNOON AND SOME OF THESE COULD BE QUITE STRONG
WITH LARGE HAIL AND DAMAGING WIND GUSTS THE MAIN THREATS. HAVE
UPDATED THE GRIDS...ZONES...AND HWO TO REFLECT THESE EXPECTATIONS AND
ALSO INCORPORATED THE LATEST GUIDANCE...OBS...AND TRENDS INTO THE T
AND TD GRIDS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 345 AM EDT THU MAY 22 2014
MODELS HAVE BEEN HAVING A DIFFICULT TIME RESOLVING THE CLUSTERS OF
THUNDERSTORMS THAT HAVE BEEN PLAGUING THE AREA SINCE LATE WEDNESDAY
EVENING. THE FORECAST FROM 6Z THROUGH NOW WERE UPDATED MOSTLY USING
THE LATEST TRENDS OBSERVED IN RADAR AND SATELLITE IMAGERY. CURRENT
ACTIVITY HAS BEEN SHOWING A STEADY WEAKENING TREND OVER THE PAST HOUR
OR SO. ALL INDICATIONS ARE THAT ANY REMAINING THUNDERSTORMS WILL
PRODUCE MINIMAL WIND GUSTS AND ISOLATED INSTANCES OF LOCALLY HEAVY
RAINFALL THROUGH THE REMAINDER OF THE OVERNIGHT. MORE STORMS CONTINUE
TO FORM IN A PREFERRED AREA OF LIFT AND MOISTURE CONVERGENCE ACROSS
SOUTHERN INDIANA AND WILL LIKELY CONTINUE TO MOVE ACROSS CENTRAL AND
EASTERN KENTUCKY THROUGH EARLY THIS MORNING. THE MODELS ARE
INDICATING THAT THERE WILL BE BRIEF LULL IN ACTIVITY IN THE
MORNING...BEFORE THINGS RAMP BACK UP A BIT DURING THE AFTERNOON HOURS
AS A COLD FRONT SAGS SLOWLY SOUTHWARD ACROSS THE REGION OUT OF THE
OHIO VALLEY. THE MODEL CONSENSUS SAYS THAT THE LAST SHOWERS AND
STORMS WILL BE OUT OF THE AREA AROUND 5Z FRIDAY. THERE IS A SLIGHT
RISK THAT A FEW STORMS COULD APPROACH SEVERE LIMITS ALONG AND JUST
NORTH OF THE TENNESSEE BORDER TODAY...AS THIS WAS MENTIONED IN THE
HAZARDOUS WEATHER OUTLOOK EVEN THOUGH CONFIDENCE IS NOT HIGH THAT
THIS WILL OCCUR. STRONG WINDS AND LARGE HAIL WOULD BE THE PRIMARY
THREATS WITH ANY STORMS THAT REACH SEVERE STATUS. THE WEATHER FOR
THURSDAY NIGHT AND FRIDAY WILL DRY AND SLIGHTLY COOLER AS ANOTHER
RIDGE OF HIGH PRESSURE SETTLES OVER THE AREA.
TEMPERATURES TODAY WILL BE RUNNING ABOVE NORMAL ONCE AGAIN WITH
READINGS EXPECTED TO TOP OUT AROUND 80 DEGREES ACROSS THE AREA AS THE
AIR MASS BEHIND THE COLD FRONT QUICKLY MODIFIES. THE FRONT ITSELF IS
NOT ALL THAT WELL DEFINED SO THE AIR BEHIND IT WILL PROBABLY NOT COOL
THINGS OFF VERY MUCH ONCE THE FRONT HAS PASSED. IN SPITE OF THE
SLIGHTLY COOLER AIR MASS...TEMPERATURES ON FRIDAY SHOULD STILL BE
ABLE TO TOP OUT IN THE UPPER 70S ACROSS THE BOARD.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU MAY 22 2014
THE MODELS IN THE LONG TERM START OUT IN VERY GOOD AGREEMENT WITH A
CUT OFF UPPER LOW OVER ARIZONA...UPPER RIDGING OVER THE PLAINS AND
AN UPPER TROUGH OVER THE EAST COAST. AT THE SURFACE HIGH PRESSURE IS
DOMINATING THE AREA. THE UPPER LOW OVER ARIZONA TRACKS SLOWLY TO THE
NORTHEAST OVER TIME AS THE RIDGE AXIS MOVE SLOWLY TO THE EAST AND
WILL BE LOCATED OVER THE MISSISSIPPI VALLEY BY SATURDAY EVENING. BY
TUESDAY AFTERNOON...SOME AFTERNOON AIR MASS THUNDERSTORMS MAY BE
POSSIBLE AS THE UPPER LOW APPROACHES THE AREA. BY THIS TIME THE
MODELS ARE STARTING TO DIVERGE AND CONFIDENCE PLUMMETS. ISOLATED TO
SCATTERED THUNDERSTORMS WILL BE POSSIBLE THROUGH THE END OF THE
PERIOD. FOR TEMPERATURES...STAYED CLOSE TO THE MODEL BLEND...HOWEVER
NUDGED THEM TOWARD THE RAW ECMWF AND MADE CORRECTIONS DUE TO
TERRAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 746 AM EDT THU MAY 22 2014
THE STORMS ARE IN THE PROCESS OF MOVING OUT OF THE AREA. MOSTLY VFR
CONDITIONS EXIST ACROSS THE AREA WITH THE EXCEPTION OF NEAR THE STORMS
AND IN SOME MID SLOPE LOCATIONS. EXPECT SOME THUNDERSTORMS TO FORM
THIS AFTERNOON...HOWEVER NOT WITH ENOUGH CONFIDENCE TO PUT IT IN THE
FORECAST. EXPECTING SOME MVFR FOG NEAR DAWN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...AR
LONG TERM...JJ
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
214 AM EDT THU MAY 22 2014
.UPDATE...
ISSUED AT 214 AM EDT THU MAY 22 2014
UPDATED THE FORECAST TO REFLECT THE CANCELLATION OF SEVERE
THUNDERSTORM WATCH 169. ALSO UPDATED THE POP...WEATHER...SKY
COVER...AND QPF GRIDS TO REFLECT RECENT TRENDS IN RADAR DATA. ANOTHER
CLUSTER OF THUNDERSTORMS IS BEARING DOWN ON OUR AREA AND WILL LIKELY
BE MOVING INTO OUR WESTERN COUNTIES IN THE NEXT COUPLE OF HOURS. THE
QUESTION WILL BE WHETHER OR NOT THIS ACTIVITY IS ABLE TO HOLD
TOGETHER AS IT MOVES IN. A FLASH FLOOD WATCH REMAINS IN EFFECT FOR
OUR SOUTHWESTERN COUNTIES THROUGH 5 AM. THE HAZARDOUS WEATHER WAS
ALSO UPDATED TO GET RID OF THE SEVERE THUNDERSTORM WATCH.
UPDATE ISSUED AT 1052 PM EDT WED MAY 21 2014
QUICK UPDATE TO BRING GRIDS IN LINE WITH LATEST TRENDS...OBS. ISSUED
A FLASH FLOOD WATCH EARLIER FOR SEVERAL HOURS FOR OUR SOUTHWESTERN
COUNTIES. COLD POOL BOUNDARY IS CURRENTLY SETTING UP ACROSS OUR
SOUTHWEST. SHORT WAVE IS PASSING THROUGH THE REGION AND MODELS
ADVERTISE A BRIEF PERIOD OF INCREASED H850 WINDS UP AGAINST AND OVER
THE COLD POOL BOUNDARY IN RESPONSE TO APPROACHING SHORT WAVE
DISTURBANCE. BASED ON UPSTREAM RAINFALL RATES AND TOTALS FROM EARLIER
THIS EVENING FELT IT PRUDENT TO ISSUE A WATCH FOR A FEW HOURS AS
SHOWERS AND THUNDERSTORMS WILL LIKELY REDEVELOP ALONG THE NW...SE
ORIENTED COLD POOL BOUNDARY DURING THE NEXT FEW HOURS. ONCE SHORT
WAVE HAS PASSED EAST OF OUR AREA H850 WINDS SHOULD SLACKEN AND THE
FLASH FLOOD THREAT SHOULD DIMINISH.
UPDATE ISSUED AT 750 PM EDT WED MAY 21 2014
DID A QUICK UPDATE TO FINE TUNE THE POP AND WX GRIDS FOCUSING A BIT
MORE ON THE WESTERN PORTION OF THE CWA ARRIVING SHORTLY AFTER 9 PM
AND RUNNING SOUTH BY 11 PM. ALSO TRIED TO CAPTURE SOME OF THE LATE
NIGHT COLD POOL IN THE T AND TD GRIDS USING THE NEWEST CONSSHORT
DATA. ALSO ADDED A STORM TOTAL QPF GRID AND SHIPPED THAT OUT TO THE
WEB. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 655 PM EDT WED MAY 21 2014
NOW THAT WE ARE UNDER A SEVERE THUNDERSTORM WATCH BOX UNTIL 2 AM EDT
HAVE UPDATED ALL THE GRIDS THROUGH THE NIGHT TO REFLECT THE SEVERE
THREATS AND TIME THE STORM CLUSTERS AS FORECASTED BY THE HRRR. DID
TEMPER THE PROGNOSIS FROM THAT MODEL WITH THE EXISTING GRIDS AND
ALSO THE 18Z NAM12. IT DOES LOOK LIKE COLD POOLS ARE DEVELOPING WITH
THE CURRENT CLUSTERS TO THE NORTH AND THIS SHOULD HELP DRIVE STRONG
TO SEVERE STORMS SOUTH INTO OUR CWA QUICKER. HAVE TIMED THE STORMS
INTO THE JACKSON AREA AROUND 9 PM WITH THEM ARRIVING AN HOUR OR SO ON
EITHER SIDE OF THAT TIME NORTHWEST AND SOUTHEAST OF THE OFFICE. KEPT
IN THE HEAVY RAIN POTENTIAL AND THE HRRR IS NOW SHOWING BETTER
TRAINING POTENTIAL FOR OUR WESTERN COUNTIES THROUGH THE NIGHT. LARGE
HAIL AND GUSTY WINDS ARE STILL THE MAIN THREATS...THOUGH. DO EXPECT
THE SEVERE MODE TO TRANSITION TO A MAINLY DAMAGING WINDS ONE OVER THE
NEXT FEW HOURS. THESE GRID UPDATES AND THE NEW WCN/ZFP/HWO HAVE BEEN
ISSUED.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 350 PM EDT WED MAY 21 2014
18Z SFC ANALYSIS SHOWS LOW PRESSURE OVER THE GREAT LAKES WITH A COLD
FRONT EXTENDING SOUTHWEST THROUGH THE NORTHWEST OHIO VALLEY AND INTO
THE MIDDLE OF MISSOURI. SOUTHEAST OF THIS...PLENTY OF FUEL IS
BUILDING FOR CONVECTION IN THE FORM OF DEWPOINTS IN THE LOW TO MID
60S AND TEMPERATURES PUSHING 80 DEGREES. THIS HAS HELPED TO PRIME
EAST KENTUCKY FOR CONVECTION LATER IN THE EVENING AND THROUGH THE
NIGHT. A FEW ROGUE SHOWERS ARE POPPING UP AND DRIFTING EAST THROUGH
THE AREA THIS AFTERNOON...BUT THE MAIN SHOW LATER THIS EVENING WILL
BE ASSOCIATED WITH THE ONGOING STORMS IN OHIO AND INDIANA EITHER
DIRECTLY OR AS A RE-SPAWNED CLUSTER ON AN OUTFLOW BOUNDARY. ON
SATELLITE...THE HIGHER DEBRIS CLOUDS ARE STARTING TO CLEAR FROM THE
EARLIER CONVECTION TO THE NORTH. THIS SHOULD HELP GIVE A FINAL PUSH
TO THE INSTABILITY OVER THE NEXT SEVERAL HOURS...THOUGH LOWER CLOUDS
WILL REMAIN DUE TO THIS HUMID ENVIRONMENT. MEANWHILE...WINDS ARE FROM
THE SOUTHWEST TO WEST AT 10 TO 20 MPH WITH SOME GUSTS TO 25 MPH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH RIDGING RETREATING TO THE
SOUTH TONIGHT IN THE FACE OF A DECENTLY STRONG SHORTWAVE MOVING
THROUGH FAST NORTHWEST FLOW...CROSSING NORTHERN KENTUCKY. THIS FLOW
PATTERN REMAINS IN PLACE INTO THE DAY THURSDAY WITH JUST A SLIGHT
SHIFT TO THE SOUTHWEST WITH THE MID LEVEL ENERGY TRACK. HEIGHT FALLS
WILL ACCOMPANY THIS ADJUSTMENT THROUGH EAST KENTUCKY INTO FRIDAY
MORNING IN CONJUNCTION WITH A SHARPER TROUGH SWEEPING SOUTHEAST
THROUGH THE EASTERN GREAT LAKES. WITH THIS AGREEMENT HAVE MAINLY
FOLLOWED THE GENERAL DETAILS FROM THE CURRENT AND PAST FEW RUNS OF
THE HRRR ALONG WITH SOME NAM12 INFLUENCE.
SENSIBLE WEATHER WILL FEATURE A LIKELY STORMY NIGHT ACROSS THE AREA.
THE HEIGHT FALLS...ENERGY PERTURBANCES AT MID LEVELS...AND A SPEED
MAX AT 500MB KEEPS THE STAGE SET FOR CONVECTIVE REDEVELOPMENT THROUGH
THE NIGHT INTO THURSDAY. INCREASING PWS...TOWARD 1.5 INCHES...THROUGH
THE AREA WILL CONTRIBUTE TO A POTENTIAL FOR HEAVY TO EXCESSIVE
AMOUNTS OF RAIN TONIGHT....ESPECIALLY IF SOLID COLD POOLS DEVELOP
ALONG WITH TRAINING OF CELLS. HOWEVER...CONFIDENCE IN ANY EXACT
SCENARIO REMAINS LOW GIVEN THE DEVELOPING CONVECTION PATTERN AND THE
CHALLENGE OF PREDICTING SUBSEQUENT INITIATION OFF OF THE SOUTHWARD
MOVING OUTFLOW BOUNDARIES. A LACK OF A CAP AND LIS TO -6/CAPES TO
2000 J/KG WILL ALSO MEAN A GOOD POTENTIAL FOR SEVERE WEATHER WITH ANY
ORGANIZED STORMS THIS EVENING AND INTO THE OVERNIGHT...SHOULD PRIOR
CONVECTION NOT STABILIZE THE ENVIRONMENT. HAVE HIT THIS POTENTIAL
HARD IN THE GRIDS...ZONES...AND HWO. AFTER A MILD NIGHT...A BOUNDARY
SHOULD BE LAYING FROM NORTHWEST TO SOUTHEAST ACROSS EAST KENTUCKY
WITH STILL A POTENTIAL FOR STRONG STORMS ACROSS SOUTHWESTERN PARTS
OF THE AREA. HAVE CONTINUED THIS THREAT INTO THE AFTERNOON. THE
BOUNDARY SHOULD WEAKEN AND DRIFT FURTHER SOUTHEAST INTO THE NIGHT
WITH LESS OF A RISK FOR CONVECTION. COOLER TEMPS WILL BE FOUND
THURSDAY NIGHT OVER OUR NORTHEAST WITH MILDER AND MUGGIER CONDITIONS
SOUTHWEST.
USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS AND THEN TACKED ON
THE BCCONSALL. MOST ADJUSTMENTS WHERE MADE FOR TERRAIN DIFFERENCES
TONIGHT AND THURSDAY NIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE
OF ALL GUIDANCE...BUT CLOSEST TO THE HIGHER MET NUMBERS TONIGHT AND
THURSDAY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 300 PM EDT WED MAY 21 2014
EXTENDED MODELS ARE IN REASONABLE AGREEMENT THROUGH THE PERIOD...BUT
AS USUAL THERE IS BETTER AGREEMENT WITH LARGE SCALE FEATURES THAN
WITH DETAILS. WE START WITH AN UPPER LEVEL DISTURBANCE THAT DROPS
SOUTHEAST THROUGH THE REGION FRIDAY...EFFECTIVELY JUMP STARING A
TEMPORARILY STALLED OUT SFC COLD FRONTAL BOUNDARY AND SWEEPING IT
OUT OF OUR AREA. THEREAFTER UPPER LEVEL RIDGING AND SFC HIGH
PRESSURE WILL BUILD OVER OUR AREA AND PROVIDE US WITH VERY PLEASANT
WEATHER FOR THE UPCOMING WEEKEND.
MODELS DIFFER MORE WITH RETURN FLOW REGIME EARLY NEXT WEEK. WARM
FRONTAL ZONE WILL MOVE BACK TO THE NORTH ACROSS THE AREA MONDAY AND
COULD PROVIDE SOME PRECIPITATION TO EASTERN KENTUCKY. THEREAFTER WE
FIND OURSELVES IN THE WARM SECTOR AND MORE SUMMER LIKE WEATHER UNTIL
THE POTENTIAL ARRIVAL OF A LOW PRESSURE SYSTEM THAT WILL SLOWLY
MEANDER ITS WAY OUT OF THE CENTRAL PLAINS. 0Z ECMWF WANTS TO BRING
THIS SLOW MOVING DISTURBANCE INTO THE HEART OF THE OHIO VALLEY BY
LATE THURSDAY INTO FRIDAY...JUST BEYOND THE FORECAST WINDOW. A MUCH
MORE INCONSISTENT GFS...AND MORE SPECIFICALLY THE 12Z RUN WANTS TO
TAKE THE DISTURBANCE TO THE GULF COAST...WHILE DEVELOPING A MUCH
STRONGER SYSTEM OVER THE OHIO VALLEY FROM ENERGY DROPPING OUT OF
CANADA DURING THAT SME TIME FRAME. PAST RUNS OF THE ECMWF HAVE SHOWN
A TENDENCY TO TAKE THE DISTURBANCE TO THE GULF COAST AS WELL...BUT
HAS NOT SHOWN ANY EVIDENCE OF SUCH A STRONG SYSTEM DROPPING OUT OF
CANADA.
FOR SENSIBLE WEATHER...ATMOSPHERE STABILIZES RAPIDLY EARLY FRIDAY
MORNING. SO ANY SHOWERS THAT MIGHT LINGER ACROSS THE AREA THURSDAY
NIGHT WILL COME TO AN END JUST AS QUICKLY EARLY FRIDAY MORNING. HIGH
PRESSURE AND A PLEASANTLY COOL AIR MASS OVER THE AREA WILL PROVIDE
GREAT WEATHER FOR THE WEEKEND. WEATHER WILL TURN MUGGY AND RELATIVELY
HOT EARLY NEXT WEEK AFTER A WARM FRONT PUNCHES ITS WAY ACROSS OUR
AREA TO THE NORTH. FOR NOW IT APPEARS THE THREAT OF SHOWERS AND
THUNDERSTORMS WILL INCREASE DAILY THROUGH THE REMAINDER OF THE
WEEK...BUT MUCH WILL DEPEND ON THE PATTERN THAT SETS UP AT THE END
OF THE FORECAST WINDOW AND BEYOND. THE ECMWF AND GFS BOTH ADVERTISE
UNSETTLED WEATHER OVER OUR AREA BY THE END OF THE WEEK BUT VIA
DIFFERENT MEANS TO THAT END. AT THIS POINT AND AFTER CONSIDERING THE
TIME OF YEAR THOUGHTS ARE THAT ANYTHING IS POSSIBLE BEYOND TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 810 PM EDT WED MAY 21 2014
CONDITIONS ARE CLINGING TO VFR THROUGH THE AREA...BUT THE CIGS DO
REMAIN NEAR MVFR IN THIS HUMID PRE-STORM ENVIRONMENT. CONVECTION...
STRONG TO SEVERE...IS ON TRACK TO PUSH SOUTH INTO THE FORECAST AREA
OVER THE NEXT SEVERAL HOURS. HAVE FORECASTED THE WORST CONDITIONS FOR
THE WESTERN PORTION OF THE AREA...LOZ AND SME. WHILE TO THE EAST...AT
JKL AND SJS...HAVE KEPT IT A BIT TAMER. EXPECT THE THREAT OF
THUNDERSTORMS AND LOWER CIGS TO LINGER THROUGH THE REMAINDER OF THE
AREA INTO THE MORNING THURSDAY...AND EARLY AFTERNOON TO THE SOUTHWEST.
HOWEVER... CONDITIONS WILL IMPROVE FROM NORTHEAST TO SOUTHWEST AS A
COLD FRONT RETREATS TO THE SOUTHWEST WITH TIME. KEPT THE RISK OF
THUNDER AND THE LOWER CIGS IN FOR SME THE LONGEST. WINDS WILL BE
OCCASIONALLY BREEZY FROM THE WEST SOUTHWEST THROUGH THE EVENING...BUT
WITH STORMS THE GUSTS COULD BE UP TO 40 KTS OR HIGHER IN THE
WEST...THOUGH CLOSER TO 30 KTS IN THE EAST. LIGHTER WEST WINDS...
OUTSIDE OF ANY STORMS...WILL FOLLOW FOR THE REST OF THE NIGHT AND
INTO THE DAY THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 5 AM EDT EARLY THIS MORNING FOR KYZ058-
068-069-079-080-083>087-111-114-116.
&&
$$
UPDATE...AR
SHORT TERM...GREIF
LONG TERM...RAY
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1146 PM CDT Wed May 21 2014
.UPDATE...
Issued at 1146 PM CDT WED MAY 21 2014
Scattered thunderstorms northeast of the PAH forecast area should
gradually migrate south with the boundary, but HRRR and NAM data
indicate any convection will be isolated to widely scattered at
best. Based on this and radar trends, have backed off pops
overnight with 14 percent southwest to slight chances across the
rest of the area. No other big changes for the overnight.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 115 PM CDT WED MAY 21 2014
Surface Based CAPEs have risen into the mid 1K J/kg range.
However, H7 Temps aoa 10C across Semo/Wky may cap convection
there. Best chance will occur tonight when boundary settles
southward, but of course diurnal aid to low level destabilization
will be lost then. Will keep close eye upon swody1 SLGT risk zone,
i.e. mainly northern/eastern counties, where boundary threatens
first.
Pops then carry with the boundary tonight thru Fri night, as it
sags southward and westward, in response to falling heights across
the Ohio Valley and ridging displacement southward/westward.
Streamline analysis reveals perturbations will thus rotate counter
clockwise around the southern U.S. high and overtop the boundary,
inducing chc cat pops, best north/east, least south/west.
80s/60s continue to be the rule, although farthest north/east may
experience the low end range around the 80/60 marks.
.LONG TERM...(Saturday through Wednesday)
Issued at 202 PM CDT WED MAY 21 2014
At the beginning of the extended forecast period (7am Saturday),
the preferred deterministic 12z Wednesday model runs of the
GFS/GEM guidance share a similarity of pushing a shortwave
through the western limb of the high amplitude ridge stretching
from the Gulf Coast to Minnesota/Wisconsin. The effective frontal
boundary is already forecast to be well southwest of the WFO PAH
forecast area during this time, but the GEM and GFS suggest that
an inverted trough over Arkansas is developing in advance of the
shortwave moving along the western limb of the ridge. A small
chance for showers and thunderstorms has been placed along the
western limb of the WFO PAH public grids (more likely in the WFO
PAH Fire Weather grids further west), where elevated convection
will be possible during the day on Saturday.
The NWS Weather Prediction Center (WPC) 1159 am Wednesday discussion
suggests a slower evolution of the mean closed low Sunday into
Monday into the Central Plains from the Eastern Rockies. There is
a subtle difference in the meridional position of the closed low
with the GEM guidance (centered closer to NW quarter of KS)
versus the GFS guidance (centered in south central KS/northern OK)
by 18z Monday. The 12z Wednesday GFS Ensemble splits the
difference and had support from the WPC. The main impact for the
WFO PAH forecast area is that with the exception of Saturday, the
interaction between the aforementioned closed low and ridge keeps
rain chances held at bay until late Monday.
By 00z Tuesday, the GFS Ensemble suggests that the central U.S.
closed low begins to open up and become more progressive, as a
western Canadian trough digs into the northwest U.S. With this in
mind, the ridge gets shifted eastward away from the WFO PAH area,
opening up a better moisture trajectory and increased instability
with sharper lapse rates moving in from the West. Therefore, from
basically Monday/Tuesday onward, a small chance of showers and
thunderstorms remains in the remainder of the forecast.
Utilized a blend of the GEM/GFS/SREF/GEFS guidance for sky, wind,
temperature, dew point, QPF, PoPs, etc...for this extended package
issuance.
&&
.AVIATION...
Issued at 1131 PM CDT WED MAY 21 2014
Will keep conditions VFR tonight through Thursday. There is
certainly a chance of convection around. But confidence in timing
and placement is too low to warrant a TS inclusion at this time.
Winds will not be of much concern. SW aob 6-8 kts overnight veering
around as a front slips south into the area (NW to NE, but light)
through Thursday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...RST
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
932 PM CDT FRI MAY 23 2014
.DISCUSSION...
SATELLITE IMAGERY THIS EVENING REVEALS EXTENSIVE AREAS OF ELEVATED
CLOUD COVER WHICH HAS RAPIDLY SPREAD E ACROSS THE REGION LATE THIS
AFTERNOON/EARLY EVENING...FROM CONVECTION OVER WCNTRL TX/SRN
OK...WITH ADDITIONAL PACIFIC MOISTURE STREAMING NE BENEATH THE AZ
CLOSED LOW...ORIGINATING FROM TS AMANDA OVER THE ERN PACIFIC. THE
00Z KSHV RAOB STILL REMAINS STRONGLY CAPPED AND QUITE DRY BENEATH
THE CLOUD COVER THIS EVENING...WITH UPPER RIDGING STILL PERSISTENT
ACROSS THE NATION/S MIDSECTION S TO THE GULF COAST. THE CONVECTION
TO OUR W HAS GRADUALLY SHOWN A VERY SLOW WEAKENING TREND OVER THE
LAST COUPLE OF HOURS...WITH THE SHORT TERM PROGS CONTINUING THIS
TREND OVERNIGHT EVEN AS A SHORTWAVE DRIFTS E INTO SW AR/NE TX
LATE. THE EARLIER PROGS WERE IN GOOD AGREEMENT WITH LITTLE IF ANY
QPF DEVELOPING LATE OVER THESE AREAS...WITH THE LATEST HRRR AND
NAM RUNS CONSISTENT WITH EARLIER RUNS WITH A MOSTLY DRY FORECAST.
THUS...HAVE TONED DOWN POPS TO SLIGHT CHANCE AFTER 06Z FOR THE
EXTREME NW ZONES...DROPPING POPS FARTHER SE...AS LIMITED MOISTURE
FARTHER S AND SUBSIDENCE BENEATH THE UPPER RIDGING IN PLACE SHOULD
PRECLUDE DEVELOPMENT ELSEWHERE OVERNIGHT. HAVE ALSO INCREASED
GRIDDED CLOUD COVER CONSIDERABLY THIS EVENING/OVERNIGHT...AS WELL
AS SATURDAY MORNING...BEFORE GRADUALLY DIMINISHING FROM W TO E BY
AFTERNOON.
EVEN WITH THE EXTENSIVE CLOUD COVER IN PLACE...02Z TEMPS ARE NEAR
THE OBSERVED READINGS 24 HOURS AGO...THUS MIN TEMPS SATURDAY
MORNING SHOULD BE COMPARABLE TO WHAT WAS OBSERVED THIS
MORNING...EXCEPT ACROSS THE ERN ZONES...WHERE SLIGHTLY WARMER
TEMPS ARE EXPECTED. HAVE ADJUSTED TEMPS AS SUCH...AS THEY RANGE
GENERALLY FROM THE MID TO UPPER 60S.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PREV DISCUSSION... /ISSUED 716 PM CDT FRI MAY 23 2014/
AVIATION...
VFR FLIGHT CATEGORIES IN PLACE THIS EVENING WITH SCATTERED TO
BROKEN CLOUDS AROUND 5-6 KFT WITH HIGHER CEILINGS ABOVE 15 KFT TO
AROUND 30 KFT. WITH A PASSING UPPER DISTURBANCE MOVING ACROSS THE
AREA THIS EVENING AND THROUGH PARTS OF TONIGHT...VERY ISOLATED
SHOWERS MAY DEVELOP...BUT CHANCE TO SMALL TO INCLUDE MENTION IN
THE 24/00Z TERMINALS. LATE TONIGHT PARTS OF DEEP E TX AND LOWER
NW LA WILL SEE A MIX OF MVFR/IFR CEILINGS AND VISIBILITIES...WHILE
MOST OTHER LOCATIONS WILL SEE BRIEF MVFR CEILINGS AND VISIBILITY
RESTRICTIONS OF 3-5 STATUTE MILES. THE MVFR/IFR CATEGORIES WILL
QUICKLY RETURN TO VFR CONDITIONS BETWEEN 24/13Z-24/15Z. LIGHT AND
VARIABLE WINDS TO LIGHT S-SW WINDS OF LESS THAN 7 KNOTS EXPECTED
THROUGH 24/15Z WHEN WINDS WILL BE MORE S FROM 4-8 KNOTS. /06/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 66 87 66 87 67 / 0 10 10 10 10
MLU 65 88 64 88 65 / 0 10 10 10 10
DEQ 64 86 62 87 64 / 20 30 20 10 10
TXK 66 86 65 86 65 / 10 10 10 10 10
ELD 63 87 62 88 63 / 0 10 10 10 10
TYR 67 86 66 85 68 / 10 10 10 10 10
GGG 66 86 65 85 67 / 10 10 10 10 10
LFK 68 88 67 86 67 / 0 10 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS CARIBOU ME
640 PM EDT THU MAY 22 2014
.SYNOPSIS...
WE WILL REMAIN IN A REGION OF LIGHT FLOW BETWEEN LOW PRESSURE
SYSTEMS TO OUR EAST AND WEST THROUGH FRIDAY. WEAK HIGH PRESSURE
WILL PRESS INTO THE AREA ON SATURDAY. A SMALL LOW WILL APPROACH
FROM THE NORTH LATE SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
0630 PM UPDATE: SCATTERED SHOWERS CONTINUE TO AFFECT MUCH OF THE
REGION AT THIS HOUR. BASED ON LATEST RADAR AND HRRR MODEL RUN,
INCREASED POPS THIS EVENING. ALSO MADE SOME MINOR ADJUSTMENTS TO
CLOUD COVER, TEMPERATURE, WIND GRIDS FOR THIS EVENING.
PREVIOUS DISCUSSION: A LARGE AND WEAK UPPER LEVEL LOW WILL REMAIN
ACROSS THE AREA TONIGHT AND FRIDAY AS WEAK SURFACE LOWS REMAIN TO
OUR WEST AND EAST. TONIGHT WILL BE PARTLY TO MOSTLY CLOUDY WITH
SOME SCATTERED SHOWERS THIS EVENING AND PATCHY FOG LATE TONIGHT.
FRIDAY WILL BE SIMILAR TO TODAY WITH A MOSTLY CLOUDY SKY, SOME
BRIEF BREAKS OF SUNSHINE, AND SOME SMALL SCALE CONVECTION
PRODUCING SCATTERED SHOWERS MAINLY DURING THE MIDDAY AND
AFTERNOON. TEMPS WILL BE SIMILAR TO TODAY`S ALTHOUGH HIGH PRESSURE
WELL TO THE NORTH WILL PUSH SOME SLIGHTLY COOLER MARITIME AIR
ACROSS THE REGION.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A WEAK UPPER SFC TROF IS FCST TO XTND NE-SW DOWN ACROSS THE AREA TO
A WEAK UPPER LOW VCNTY NYC... AT THE SFC...A WEAK RIDGE OF HIGH
PRES WILL XTND SWRD INTO OUR AREA FROM ERN CANADA. BEST UPPER
DYNAMICS WILL REMAIN WELL NE AND SW OF THE AREA BUT JUST ENUF
FORCING ACROSS OUR AREA TO WARRANT SLGT CHC TO LOW CHC POPS W/ BEST
POPS ACROSS SRN/SWRN AREAS FRI NGT INTO SAT AM. THE UPPER TROF IS
PROGGED TO SWING EWRD BUT GUIDANCE SUGGESTS WEAK UPPER SHORT WAVES
CONTG TO SLIDE SSEWRD IN THE NNWRLY FLOW ON THE BACK SIDE OF THIS
TROF WILL ACT TO KEEP THE THREAT OF SHOWERS GOING SAT INTO SAT EVE
ACROSS MAINLY WRN NEW ENGLAND INTO OUR WRN AREAS. WILL CONT W/ SLGT
CHC TO LOW CHC POPS W/ THE HIGHEST OF THESE AGAIN FOCUSED SW. WEAK
SFC HIGH PRES TO STRENGTHEN A BIT ACROSS THE AREA SAT NGT BEFORE LOW
PRES WELL NW OF THE REGION IS FCST DIVE SEWRD TOWARD THE AREA LATE
SUN AND SUN NGT. HIGH TEMPS SAT AND SUN WILL REMAIN JUST A LITTLE
BLO SEASONAL NORMS...
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A GENERALLY UNSETTLED PATTERN TO PERSIST OVER FORECAST AREA THROUGH
WEDNESDAY. A SHORT WAVE EMBEDDED IN PERSISTENT NORTHWESTERLY FLOW
WILL TRACK ACROSS THE FORECAST AREA MONDAY. TOO MUCH UNCERTAINTY
REMAINS TO BE ABLE TO SAY THIS MAY BE FIRST CONVECTIVE OUTBREAK OF
THE SEASON. LONG RANGE MODELS ARE IN FAIR AGREEMENT AT START OF
PERIOD BUT BEGIN TO RAPIDLY DIFFER BY LATE MONDAY. GFS TRACKS MAIN
LOW PRESSURE SOUTH OF THE FORECAST AREA LEADING TO A COOLER
SITUATION WHILE THE ECMWF KEEPS LOW FURTHER NORTH SUGGESTING A
WARM HUMID REGIME AND POSSIBLE THUNDERSTORMS. BASED ON CLIMO AND
CONSENSUS HAVE OPTED TO LEAN TOWARDS GFS AND A COOLER SHOWERY
RESULT. THIS BASIC PATTERN...GENERALLY CLOUDY AND
SHOWERY...PERSISTS THROUGH EARLY WEDNESDAY BEFORE A HINT OF HIGH
PRESSURE BEGINS BUILDING IN WITH PARTLY TO MOSTLY SUNNY SKIES AND
WARMER TEMPS. OVERALL HIGH TEMPS SHOULD REMAIN NEAR AVERAGE WITH
LOWS A FEW DEGREES ABOVE NORMAL DUE TO CLOUD COVER.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: CEILINGS TONIGHT WILL RANGE FROM MVFR THIS EVENING TO
IFR LATE TONIGHT. CEILINGS ON FRIDAY SHOULD IMPROVE TO MVFR IN THE
MORNING AND POSSIBLY VFR BY MIDDAY.
SHORT TERM: EXPECT MAINLY VFR CONDS SAT THRU SUN... MODELS DRIVE
LOW PRES SEWRD FROM VCNTY HUDSON BAY LATER SUN NGT INTO TUE W/
VARYING SOLNS CONCERNING STRENGTH/TIMING OF THIS SYSTEM/SYSTEMS.
WOULD EXPECT MAINLY VFR W/ MVFR TO PSBL BRIEF IFR IN ANY SHOWERS.
CONFIDENCE DURING THIS PERIOD IS LOW...
&&
.MARINE...
NEAR TERM: WINDS AND SEAS WILL REMAIN BELOW SCA TONIGHT AND
FRIDAY. HUMID AIR OVER THE WATERS WILL PRODUCE SOME AREAS OF FOG
MAINLY LATE AT NIGHT AND EARLY FRIDAY MORNING.
SHORT TERM: A WEAK SFC PRES GRADIENT WILL REMAIN ACROSS THE WATERS
SAT THRU SUN RESULTING IN WNDS/SEAS REMAIN BLO SCA LEVELS...
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...BLOOMER/FITZSIMMONS
SHORT TERM...KHW
LONG TERM...PJR
AVIATION...BLOOMER/FITZSIMMONS/KHW
MARINE...BLOOMER/FITZSIMMONS/KHW
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1109 AM EDT THU MAY 22 2014
.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION LATE THIS AFTERNOON. AN UPPER
LEVEL DISTURBANCE WILL PIVOT ACROSS THE AREA FRIDAY...FOLLOWED BY
BUILDING HIGH PRESSURE FOR THE WEEKEND.
&&
.NEAR TERM /TODAY/...
SFC ANLYS SHOWED LOW PRES OVR LAKE ONTARIO W/ A WARM FNT
STRETCHING S OF NJ AND A CD FNT XTNDG ACROSS OH. MID ATLC HAS
ALREADY WARMED INTO THE M70S...GOING UP INTO THE M80S. SKIES HV
STARTED THE DAY CLR WHICH WL ALLOW FOR GOOD HTG.
SPC HAS AREA E OF I-95 IN A SLT RISK FOR WIND/HAIL. THIS IS WHAT
THE SREF SVR PARAMETES ARE IMPLYING...ARND 00Z. HOWEVER THIS IN
NOT BEING SEEN IN THE HRRR HRLY PLOT. LOOKING AT THE SNDG THIS
SCENARIO COULD BEST BE DESCRIBED AS "MDTLY HIGH CAPE/MINIMAL
SHEAR" - AFTN HTG COULD PRODUCE UP TO 1500 JOULES..BUT UPR LVL
WIND FIELD LOOKS TO BE ALMOST SINGULARLY WNW. HENCE GUSTY
WINDS/HAIL ARE WHAT WOULD BE CONSIDERED THE BEST THREAT.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
FNT SHUD CLR AREA BY ELY EVNG...W/ CAA/LWR DEWPTS/CLRG SKIES
ARRIVING THRU THE NGT. HWVR...PTTN ALOFT WL STILL BE CHARACTERIZED
BY BROAD TROFFING ACRS THE NERN CONUS. A S/WV W/IN THIS TROF WL BE
PIVOTING ACRS AREA FRI. THAT WL SUPPORT ADDTL CLDS AND 20-30 POPS
DURING THE DAY. ATM WL BE STBL BY THIS PT...SO ANY PCPN WUD BE JUST
SHRA.
A BLEND OF MOS GNLY ACCEPTED...XCPT MAV MAXT FRI SEEMED A BIT TOO
WARM.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
SKIES WILL CLEAR THROUGH THE EARLY MORNING HOURS SAT AND MOST OF THE
AREA WILL BE MOSTLY SUNNY FOR SUNRISE SAT. THE EXCEPTION IS ALONG
THE BAY...WHERE LOW END RAIN CHANCES WERE KEPT THROUGH THE DAY AS
THE SURFACE LOW DEEPENS AS IT MOVES AWAY FROM THE MID ATLANTIC
COAST. ANY LINGERING PRECIP THAT DOES FORM SHOULD BE OUT OF THE AREA
BY SATURDAY EVENING. HIGH TEMPS WILL GENERALLY BE IN THE MID 70S FRI
AND SAT WITH LOWS AROUND 50 BOTH NIGHTS.
SATURDAY NIGHT INTO SUNDAY BECOME QUIET WEATHER-WISE WITH
WEAKENING NORTHWEST FLOW ALOFT AND SURFACE HIGH PRESSURE BUILDING
ACROSS THE MID-ATLANTIC. RISING HEIGHTS SUNDAY INTO EARLY NEXT
WEEK WILL BRING A GOOD WARMING TREND AS FAIRLY BROAD UPPER RIDGE
PUSHES EAST AHEAD OF A PROGRESSIVE PACIFIC LOW. HIGH PRESSURE IN
PLACE SUNDAY /AND SLOW TO MOVE OUT/ WILL LIMIT MOISTURE RETURN
INTO MONDAY. STRONGER SOUTHWEST FLOW AND INCREASING MOISTURE WILL
BRING THE CHANCE OF STORMS BACK INTO THE FORECAST TUESDAY ON THE
NORTHERN EDGE OF A BUILDING THERMAL RIDGE.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
VFR CONDS MAJORITY OF TDA. LATE AFTN/ERLY EVE TSTMS PSBL. GUSTY NW
WINDS ERLY THIS EVE.
WL HV AN UPR LVL DISTURBANCE ROTATING THRU FRI. VFR CIGS BKN050...
MAINLY DRING THE AFTN-ELY EVE. WNDS WL PICK UP AGN AS WELL...
10-15 KT W/ A FEW G20KT.
VFR UNDER HIPRES SAT-MON.
&&
.MARINE...
WINDS IN THE 10-15 KT RANGE ATTM BUT ARE XPCTD TO INCRS THIS AFTN
AHD OF AN APRCHG CD FNT. SCA IN EFFECT THIS AFTN. TSTMS ARE PSBL
LATE THIS AFTN/ERLY EVE.
MIXING WL BE MAINTAINED INTO THE NGT...SPCLY ON THE OPEN WATERS...
AND WL BE ENHANCED BY A S/WV FRI. SCA FOR MOST OF THE WATERS /XPCT
FOR MID-UPR PTMC/ CONTS TNGT. WL ADD SCA FOR ALL WATERS FRI.
HIGH PRESSURE WILL BUILD INTO THE REGION LATE IN THE WEEKEND AND
EARLY NEXT WEEK.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 6 PM EDT
FRIDAY FOR ANZ530>534-537>541-543.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 11 PM EDT
THIS EVENING FOR ANZ535-536-542.
SMALL CRAFT ADVISORY FROM 10 AM TO 6 PM EDT FRIDAY FOR ANZ535-
536-542.
&&
$$
UPDATE...WOODY!
PRVS...HTS
AREA FORECAST DISCUSSION
NWS DULUTH MN
806 PM CDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 806 PM CDT FRI MAY 23 2014
SLOWED THE TIMING OF THE POPS INTO THE NW QUAD OF THE FA TO AFTER
06Z. STORMS THAT HAVE BEEN PERCOLATING THROUGH NW MN ARE
DIMINISHING AS THEY MOVE E INTO THE DRIER AIR. SFC RIDGE AXIS IS
OVER THE EASTERN EDGE OF THE FA AT 01Z WHICH IS ALLOWING FOR A SLY
WIND TO USHER IN WARM/MOIST AIR. MADE SOME MINOR ADJUSTMENTS TO
ACCOUNT FOR THIS TREND.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
AN UPPER LEVEL RIDGE AND SURFACE HIGH HAS KEPT THE NORTHLAND UNDER
MOSTLY SUNNY SKIES WITH WARM TEMPERATURES TODAY.
WAA TONIGHT...ALONG WITH INCREASING INSTABILITY AND STEEPER LAPSE
RATES MAY LEAD TO SOME SHOWERS OVER PORTIONS OF OUR
WESTERN/NORTHERN CWA. SHOWERS AND THUNDERSTORMS HAVE FIRED OVER
FAR WESTERN MINNESOTA THIS AFTERNOON...AND THE LATEST HRRR DEPICTS
THIS AND HAS IT DIMINISHING WITH LOSS OF HEATING AND AS IT MOVE
AWAY FROM THE BETTER INSTABILITY. THE LATEST WRF-NMM ALSO DEPICTS THIS
ACTIVITY AND HAS IT DISSIPATING BEFORE IT REACHES OUR CWA. WE WILL
LEAVE IT OUT EARLY THIS EVENING...THEN KEEP SOME SMALL POPS LATER
TONIGHT.
LOWER STABILITY WILL RESIDE OVER FAR NORTHERN MINNESOTA
SATURDAY...AND WE KEPT A MENTION OF SOME SHOWERS OR THUNDERSTORM
THERE. MOST AREAS WILL SEE PARTLY TO MOSTLY SUNNY SKIES THOUGH AND
TEMPERATURES A BIT WARMER THAN TODAY. WE THINK THE SOUTHWEST FLOW
WILL BE STRONG ENOUGH TO KEEP A LAKE BREEZE FROM FORMING AT THE
HEAD OF THE LAKE AND ALONG THE SOUTH SHORE FOR MUCH OF THE DAY.
HOWEVER...ONE MAY BE ABLE TO DEVELOP LATE IN THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
GOOD CONTINUITY FROM PREVIOUS FCST WITH A SOMEWHAT SPLIT FLOW IN THE
MID LVLS THIS PERIOD. THERE ARE TWO KEY FEATURES OF NOTE IN THE NEXT
5 TO 7 DAYS. FIRST...A SLOW MOVING CLOSED LOW OVER THE SRN ROCKIES
WILL TRACK INTO THE SRN PLAINS BY MIDWEEK. SECOND...A WEAK FRONTAL
BDRY ACCOMPANIED BY A SHORTWAVE TROF WILL SLIDE OVER THE CWA AMIDST
A DEVELOPING RIDGE. THIS SECOND FEATURE WILL BRING A PERIOD OF
SHOWERS/STORMS TO THE NORTHLAND MAINLY SUNDAY AND SUNDAY NIGHT.
THERE ARE DIFFERENCES IN HOW FAST INITIAL PRECIP MOVES INTO THE AREA
HOWEVER GOOD AGREEMENT EXISTS IN THE MASS FIELDS TO HAVE MODERATE
CONFIDENCE IN THE FCST. GEM REMAINS AN OUTLIER SIMILAR TO YESTERDAY
SO ITS OUTPUT WAS GIVEN LOWER CONSIDERATION. MAIN CHANGE TO
YESTERDAYS FCST WAS TO PUSH PRECIP OUT OF THE REGION MORE QUICKLY
MONDAY AS FRONTAL BDRY HEADS SOUTH AND SFC HIGH BUILDS INTO THE
AREA. BUILDING MID LVL RIDGE TUESDAY SHOULD ASSIST WITH STRENGTHENING
OF SFC HIGH AND WEDGE OF COOL DRY AIR ADVECTING DOWN LAKE INTO TWIN
PORTS. LATER FCSTS MAY NEED TO LOWER TEMPS/DEWPOINTS DURING THIS
TIME. WILL KEEP MON NIGHT THROUGH WED NIGHT DRY UNTIL NEXT POTENTIAL
FOR PRECIP ARRIVES LATE WEEK. TEMPS REMAIN ABOVE CLIMO EXCEPT NEAR
IMMEDIATE LAKEFRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 634 PM CDT FRI MAY 23 2014
VFR THROUGH THE FORECAST. HAVE VCSH MENTIONS AT BRD/HIB/INL AROUND
04Z THROUGH 12Z. WENT WITH A PREDOMINATE -SHRA AT INL FROM 08Z TO
12Z. CONFIDENCE IS LOW IN MENTIONING OF THUNDER ATTM. GUSTY SW
WINDS AT BRD/HIB/INL AFTER 16Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 50 76 56 78 / 0 10 10 20
INL 55 80 58 74 / 20 20 30 60
BRD 55 81 59 81 / 0 10 20 40
HYR 49 79 54 81 / 0 0 0 10
ASX 46 78 53 80 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...CANNON
AVIATION...GSF
AREA FORECAST DISCUSSION
NWS DULUTH MN
634 PM CDT FRI MAY 23 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
AN UPPER LEVEL RIDGE AND SURFACE HIGH HAS KEPT THE NORTHLAND UNDER
MOSTLY SUNNY SKIES WITH WARM TEMPERATURES TODAY.
WAA TONIGHT...ALONG WITH INCREASING INSTABILITY AND STEEPER LAPSE
RATES MAY LEAD TO SOME SHOWERS OVER PORTIONS OF OUR
WESTERN/NORTHERN CWA. SHOWERS AND THUNDERSTORMS HAVE FIRED OVER
FAR WESTERN MINNESOTA THIS AFTERNOON...AND THE LATEST HRRR DEPICTS
THIS AND HAS IT DIMINISHING WITH LOSS OF HEATING AND AS IT MOVE
AWAY FROM THE BETTER INSTABILITY. THE LATEST WRF-NMM ALSO DEPICTS THIS
ACTIVITY AND HAS IT DISSIPATING BEFORE IT REACHES OUR CWA. WE WILL
LEAVE IT OUT EARLY THIS EVENING...THEN KEEP SOME SMALL POPS LATER
TONIGHT.
LOWER STABILITY WILL RESIDE OVER FAR NORTHERN MINNESOTA
SATURDAY...AND WE KEPT A MENTION OF SOME SHOWERS OR THUNDERSTORM
THERE. MOST AREAS WILL SEE PARTLY TO MOSTLY SUNNY SKIES THOUGH AND
TEMPERATURES A BIT WARMER THAN TODAY. WE THINK THE SOUTHWEST FLOW
WILL BE STRONG ENOUGH TO KEEP A LAKE BREEZE FROM FORMING AT THE
HEAD OF THE LAKE AND ALONG THE SOUTH SHORE FOR MUCH OF THE DAY.
HOWEVER...ONE MAY BE ABLE TO DEVELOP LATE IN THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
GOOD CONTINUITY FROM PREVIOUS FCST WITH A SOMEWHAT SPLIT FLOW IN THE
MID LVLS THIS PERIOD. THERE ARE TWO KEY FEATURES OF NOTE IN THE NEXT
5 TO 7 DAYS. FIRST...A SLOW MOVING CLOSED LOW OVER THE SRN ROCKIES
WILL TRACK INTO THE SRN PLAINS BY MIDWEEK. SECOND...A WEAK FRONTAL
BDRY ACCOMPANIED BY A SHORTWAVE TROF WILL SLIDE OVER THE CWA AMIDST
A DEVELOPING RIDGE. THIS SECOND FEATURE WILL BRING A PERIOD OF
SHOWERS/STORMS TO THE NORTHLAND MAINLY SUNDAY AND SUNDAY NIGHT.
THERE ARE DIFFERENCES IN HOW FAST INITIAL PRECIP MOVES INTO THE AREA
HOWEVER GOOD AGREEMENT EXISTS IN THE MASS FIELDS TO HAVE MODERATE
CONFIDENCE IN THE FCST. GEM REMAINS AN OUTLIER SIMILAR TO YESTERDAY
SO ITS OUTPUT WAS GIVEN LOWER CONSIDERATION. MAIN CHANGE TO
YESTERDAYS FCST WAS TO PUSH PRECIP OUT OF THE REGION MORE QUICKLY
MONDAY AS FRONTAL BDRY HEADS SOUTH AND SFC HIGH BUILDS INTO THE
AREA. BUILDING MID LVL RIDGE TUESDAY SHOULD ASSIST WITH STRENGTHENING
OF SFC HIGH AND WEDGE OF COOL DRY AIR ADVECTING DOWN LAKE INTO TWIN
PORTS. LATER FCSTS MAY NEED TO LOWER TEMPS/DEWPOINTS DURING THIS
TIME. WILL KEEP MON NIGHT THROUGH WED NIGHT DRY UNTIL NEXT POTENTIAL
FOR PRECIP ARRIVES LATE WEEK. TEMPS REMAIN ABOVE CLIMO EXCEPT NEAR
IMMEDIATE LAKEFRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 634 PM CDT FRI MAY 23 2014
VFR THROUGH THE FORECAST. HAVE VCSH MENTIONS AT BRD/HIB/INL AROUND
04Z THROUGH 12Z. WENT WITH A PREDOMINATE -SHRA AT INL FROM 08Z TO
12Z. CONFIDENCE IS LOW IN MENTIONING OF THUNDER ATTM. GUSTY SW
WINDS AT BRD/HIB/INL AFTER 16Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 48 76 56 78 / 10 10 10 20
INL 50 80 58 74 / 20 20 30 60
BRD 52 81 59 81 / 10 10 20 40
HYR 43 79 54 81 / 0 0 0 10
ASX 43 78 53 80 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...CANNON
AVIATION...GSF
AREA FORECAST DISCUSSION
NWS DULUTH MN
257 PM CDT THU MAY 22 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 255 PM CDT THU MAY 22 2014
CLOUDS HAVE BEEN VERY SLOW TO DISSIPATE TODAY...HANGING TOUGH FROM
KINL TO KDLH TO KHYR AND KPBH. THE RAP HAS BEEN DOING A DECENT JOB
DEPICTING THESE CLOUDS. COLD TEMPS AND CYCLONIC FLOW ALOFT HAVE
CONTRIBUTED TO A FAVORABLE SET UP FOR THE CLOUDS.
THE CLOUDS HAVE BEEN SLOWLY DIMINISHING THIS AFTERNOON AND WITH
LOSS OF HEATING...WE EXPECT IT TO CONTINUE. THE RAP ALSO SHOWS THE
CLOUDS DIMINISHING THIS EVENING. THE HIGH WILL PASS OVER THE CWA
AND WINDS WILL BECOME LIGHT ALLOWING TEMPS TO COOL INTO THE MID
THIRTIES TO LOWER FORTIES. SOME OF THE COOLER LOCALES ACROSS THE
CWA MAY DROP TO NEAR FREEZING.
AS THE HIGH CONTINUES ITS SLOW EASTWARD TRACK FRIDAY...WINDS WILL COME
AROUND TO MORE SOUTHERLY FOR MOST AREAS. IT SHOULD BE WARMER WITH
MOST AREAS CLIMBING TO 69 TO 75. AREAS AROUND LAKE SUPERIOR WILL BE
COOLER WITH LIGHT ONSHORE WINDS EXPECTED. THERE SHOULD ALSO BE MORE
SUN AS UPPER LEVEL RIDGING AND WARMING TEMPS OCCUR.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 PM CDT THU MAY 22 2014
OVERALL SYNOPTIC SCALE PATTERN FEATURES A MID LVL RIDGE OVER NRN
PLAINS AND UPPER MIDWEST NEXT 5 TO 7 DAYS. WITHIN THAT REGIME THERE
IS SOME AGREEMENT AMONGST MED RANGE MDL SUITE THAT A PROGRESSIVE
SHORTWAVE TROF MAY DAMPEN RIDGE ENOUGH TO WARRANT AN EPISODE OF
PRECIP. AS MID LVL RIDGE MOVES INTO REGION THIS WEEKEND WIT WILL BE
ACCOMPANIED BY A BROAD PATTERN OF WARM ADVECTION IN THE LOW/MID
LAYERS. A PROGRESSIVELY MORE MOIST ATMOSPHERE WILL DEVELOP AND THERE
IS A CHC THAT SCTD CONVECTION MAY OCCUR AS EARLY AS SAT AFTN OVER
WRN CWA. HOWEVER WILL ACCEPT MDL TREND TO SLOW DOWN ARRIVAL OF
SUFFICIENT MOISTURE AND START PRECIP POTENTIAL SAT NIGHT. GRADUAL
INCREASE IN POPS SUNDAY WITH HIGHEST PROB OCCURRING SUN NIGHT/EARLY
MONDAY AS LARGE SCALE ASCENT IS MAXIMIZED WITH PASSAGE OF SHORTWAVE
ALOFT. SFC HIGH WILL BUILD SOUTH BEHIND THE DEPARTING SHORTWAVE
MONDAY. SOME TIMING DIFFERENCES WITH REGARD TO HOW SOON THE PRECIP
MOVES SOUTH OF THE CWA. BEYOND THAT UNCERTAINTY INCREASES AS INITIAL
SFC BDRY MOVES WELL SOUTH OF REGION TUESDAY AND THEN POSSIBLY
RETREATS NORTH BY MIDWEEK. ALLBLEND SOLUTION GIVES POPS ACROSS SRN
CWA TUES/WED HOWEVER NOT CONFIDENT THAT ENOUGH MOISTURE IS EVIDENT.
WILL LET NEXT SHIFT SHIFT TO A DRIER PATTERN IF MDL TRENDS CONTINUE.
TEMPS REMAIN ABOVE NORMAL THROUGH PERIOD AS 50H PATTERN ADVERTISES
ANOMALOUS RIDGING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1223 PM CDT THU MAY 22 2014
OTHER THAN A BRIEF PERIOD OF MVFR AT KINL EARLY THIS AFTERNOON
EXPECT VFR THROUGH THE PERIOD AS SFC HIGH PREVAILS. CLOUD DECK
OVER THE REGION WILL SLOWLY DECREASE THIS AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 41 70 46 75 / 0 0 0 10
INL 39 73 50 79 / 0 0 10 10
BRD 42 75 55 79 / 0 0 10 10
HYR 38 75 45 76 / 0 0 0 10
ASX 39 68 43 72 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...CANNON
AVIATION...CANNON
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1237 AM CDT THU MAY 22 2014
.UPDATE...
ISSUED AT 805 PM CDT WED MAY 21 2014
CLOUDS ARE HANGING TOUGH AND NOT EXPECTING ANY ADDITIONAL CLEARING
FROM WHAT HAS ALREADY OCCURRED THIS EVENING. WITH THIS CLOUD
COVER...HAVE BUMPED UP MIN TEMPS A FEW DEGREES AS WELL AS
DEWPOINTS. HAVE REMOVED THE RAIN MENTION FROM THE ARROWHEAD AS
WELL.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 302 PM CDT WED MAY 21 2014
CLOUDS HAVE BEEN VERY SLOW TO DIMINISH OVER THE NORTHLAND TODAY
UNDER COOL NORTHWESTERLY FLOW ALOFT. THEY ARE STARTING TO THIN TO
OUR SOUTHWEST...AND THAT TREND WILL CONTINUE OVERNIGHT. WE DID
INCREASE CLOUDS THIS EVENING FOR MOST AREAS...FOLLOWING CLOSE TO
THE RAP LOW LEVEL MOISTURE FIELDS. THE LATEST RAP ALSO SHOWS
CLOUDS HANGING IN FOR MUCH OF THE NIGHT OVER THE NORTHEAST HALF TO
TWO THIRDS OF THE CWA. WE WILL MONITOR CLOUD TRENDS TONIGHT AND
WE MAY NEED TO BEEF UP CLOUDS AND ADJUST LOWS UP.
WE BUMPED UP CLOUDS A BIT ON THURSDAY AND WENT WITH PARTLY CLOUDY
SKIES. WE THINK THERE COULD BE CLOUDS AROUND EARLY AND WE SHOULD
DEVELOP SOME CU THROUGH THE DAY. AT THE SURFACE...HIGH PRESSURE
WILL BE OVERHEAD BUT TEMPS WILL STILL BE COOL ALOFT.
HIGH PRESSURE WILL CONTINUE TO IMPACT THE REGION AND PROVIDE DRY
CONDITIONS INTO FRIDAY. TEMPERATURES WILL WARM FROM THE SIXTIES
THURSDAY INTO THE SEVENTIES FOR MOST AREAS ON FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 302 PM CDT WED MAY 21 2014
THE EXTENDED PERIOD FROM FRIDAY NIGHT THROUGH NEXT WEDNESDAY FINALLY
LOOKS TO BE A SUSTAINED PERIOD OF AT OR ABOVE NORMAL TEMPS ACROSS
MOST OF THE REGION. WHILE AREAS NEAR LAKE SUPERIOR WILL LIKELY SEE
RATHER ROBUST LAKE BREEZE FRONTS DURING THE MIDDAY TO EVENING HOURS
SAT-MON TIME FRAME..THE REMAINDER OF THE DULUTH CWA SHOULD SEE HIGH
TEMPS WELL INTO THE 70S..ALONG WITH DEWPOINTS REACHING INTO THE 60S
BY THE MON-WED TIME FRAME.
SURFACE AND MID LEVEL RIDGE AXIS SHOULD BE OVER THE CWA NEAR THE
BEGINNING OF THE PERIOD FRI NIGHT/SAT..BRINGING A COOL MORNING.
HOWEVER..RETURN SOUTH/SOUTHEAST FLOW SHOULD DEVELOP IN MOST AREAS BY
MIDDAY SAT..WITH BEST CHANCES FOR RAIN SHOWERS REMAINING TO OUR WEST
UNTIL LATER IN THE DAY. RATHER ROBUST DIFFERENTIAL HEATING SHOULD
RESULT IN A FAIRLY STRONG LK SUPERIOR LAKE BOUNDARY DURING THE
AFTERNOON..WITH HIGH TEMPS OCCURRING LATE MORNING TO EARLY AFTERNOON
IN THE FAVORED LAKE BREEZE LOCATIONS. GIVEN THAT LOW LEVEL FLOW WILL
LIKELY STILL HAVE SOME EASTERLY COMPONENT..THERE SEEMS TO BE
POTENTIAL FOR ANY LAKE BREEZE BOUNDARY TO PENETRATE RATHER FAR
INLAND BY LATE AFTERNOON SATURDAY..WITH SOME COOLING EFFECT POSSIBLY
NOTED AS FAR WEST AS THE GRAND RAPIDS/IRON RANGE/INTERIOR ARROWHEAD
AREAS BY EVENING.
CHANCES FOR SHOWERS/TSTORMS WILL INCREASE FROM WEST TO EAST LATE SAT
INTO MONDAY AS NORTHERN STREAM WAVE PUSHES A WEAK FRONT INTO THE NE
MN AREA..BEFORE THE FRONT STALLS AND/OR WASHES OUT EARLY NEXT WEEK.
THE LARGE SOUTHERN STREAM UPPER LOW TRAVERSING THE PLAINS STATES TO
OUR SOUTH DURING THIS TIME AND PRECIPITATION/DEEP CONVECTION
ASSOCIATED WITH IT MAY ACT TO LESSEN THE NORTHWARD LOW LEVEL
MOISTURE TRANSPORT. HOWEVER..SUFFICIENT MOISTURE IS EXPECTED TO BE
IN PLACE TO SUPPORT SOME SHOWERS/STORMS IN VICINITY OF THE LINGERING
BOUNDARY FROM SAT NIGHT INTO MONDAY. AT THIS TIME..IT APPEARS THAT
INSTABILITY AND ESPECIALLY WIND SHEAR/FLOW WILL BE TOO WEAK TO
SUPPORT MUCH IN THE WAY OF ANY SEVERE WEATHER POTENTIAL. AGAIN..WE
EXPECT A LK SUPERIOR LAKE BREEZE FRONT TO DEVELOP SUN-MON AS
WELL..RESULTING IN LATE MORNING/EARLY AFTERNOON HIGH TEMPS IN AREAS
NEAR THE LAKE.
BY MID WEEK..A RATHER SIGNIFICANT LARGE SCALE PATTERN SHIFT TO A
PACNW UPPER TROF AND BROAD WSW MID LEVEL FLOW FROM THE GREAT BASIN
TO MANITOBA/NW ONTARIO SHOULD RESULT IN THE BUILDING OF A LOW LEVEL
THERMAL RIDGE FROM THE DAKOTAS INTO NW MINNESOTA. WHILE THE BEST
FLOW AND SHEAR AS WELL AS INSTABILITY AXIS IS EXPECTED TO REMAIN TO
OUR WEST BASED ON CURRENT GUIDANCE..THERE WILL STILL BE POTENTIAL FOR
SOME ELEVATED STORMS WITHIN THE LOW LEVEL WARM/MOIST ADVECTIVE ZONE
JUST DOWNSTREAM FROM THE MAIN UPPER LEVEL RIDGE AXIS ACROSS THE
DULUTH CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1233 AM CDT THU MAY 22 2014
AN AREA OF MVFR CIGS WILL HOVER OVER THE MN ARROWHEAD OVERNIGHT
AND MAINLY AFECT THE INL AREA. SCT-BKN CIGS OVR KHIB AND KDLH BUT
MAINLY FROM BKN-OVC040-050. CIGS OVR THE AREA WILL BE ALL VFR AFT
14Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 43 69 49 71 / 0 0 0 10
INL 40 73 51 78 / 0 10 10 20
BRD 43 75 54 77 / 0 10 10 10
HYR 39 73 49 76 / 0 0 0 10
ASX 39 68 46 72 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...MILLER
AVIATION...CLC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1207 AM CDT Thu May 22 2014
.SHORT TERM...(This Evening through Thursday Night)
Issued at 305 PM CDT WED MAY 21 2014
The focus through the period continues to be on thunderstorms
chances. For this afternoon the frontal boundary currently slowly
moving south across portions of the NRN CWA should serve as the
focus for isolated to scattered storms. Dprog/Dt of the HRRR paints
a narrow zone of storms along the front forming by 5 to 6 pm in our
CWA, then they move east and clear the CWA by around 9 or 10 pm.
Latest ACARS soundings out of KMCI depict the CAP slowly eroding so
confidence is rather high we should see a few storms along the
front. Given the large CAPE and modest shear profiles large hail
and damaging winds will be the main threats.
Late overnight tonight a large complex of storms may work into the
CWA from the west/southwest. At this time the better chances of
seeing storms appears to favor the WRN and NRN areas of the CWA.
The complex of storms should be weakening as they move in, thus the
overnight SVR potential is rather low.
Tomorrow most of the CWA will be north of the surface front so high
temps should be back down to near normal... mid to upper 70s with
mid 80s across our far SRN zones. Precip wise is a tough call depending
on how long any overnight activity lingers into the daylight morning
hours, residual cloud debris and degree of instability. So for now
just have low chance pops through tomorrow into tomorrow evening
given a lack upper level forcing.
.LONG TERM...(Friday through Wednesday)
Issued at 305 PM CDT WED MAY 21 2014
A rather messy short to medium range forecast through the Memorial
Day holiday and into much of next week. Why? The development of
the cutoff low across the southwestern United States that will
slowly crawl eastward into early next week. This low is expected to
pull increasing amounts of low-mid level moisture northward into the
Plains which will interact with a stalled frontal boundary in the
region.
By Friday morning, precipitation chances will increase briefly as a
secondary shortwave drops through the Great Lakes and a brief window
of warm advection commences overnight. This upper trough will push surface
high pressure into the region, and force the stalled front well
south of the area, potentially forcing precip south and east of the
CWA Friday afternoon and evening.
It`s hard to get too specific on forecast details through this
weekend and into Monday due to shortwave timing issues. The weekend
shouldn`t be a washout, but we`ll have to carry scattered PoP
wording through Monday.
Medium range models are all over the place in the eventual track of
the upper low through the area through Thursday. ECMWF/GEM produces
fairly widespread rains for Monday and Tuesday with a northern track,
GFS dives the ejecting low too far south to produce widespread rains,
but more scattered activity. Ensemble approach provides little
benefit, with a substantial spread in solutions. For now, have to
continue to include PoPs through much of the extended.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1207 AM CDT WED MAY 21 2014
The main concern for aviators this TAF cycle will be the potential
for showers and thunderstorm during the 11Z-15Z time period. Current
thunderstorms over western Kansas will move eastward overnight moving
into the terminals around sunrise. These storms however will be
diminishing as they progress into the area so have cont to use VCTS
for timing these storms into the terminals because there is some
concern they may not hold together long enough to make it into
western Missouri. Otherwise conds will remain VFR with bkn clouds
between 4-5kft through mid morning tomorrow before scattering. There
will be another chance for thunderstorm during the evening hours
however potential seems to low for inclusion at this point. Winds
will be lgt and vrb overnight before picking up out of the ENE
tomorrow morning between 5-10kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...Pietrycha
LONG TERM...Dux
AVIATION...73
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1125 PM CDT Wed May 21 2014
.SHORT TERM: (Through Late Tonight)
Issued at 1256 PM CDT Wed May 21 2014
Cold front extended from just north of UIN southwest through MCI.
This front will move southward through our forecast area tonight, and
should extend from west central MO southeast through southern IL by
12z Thursday. The cap should break late this afternoon with
scattered convection developing along this front. The HRRR model
has most of the convection across northeast MO and west central IL
early this evening, then shifts it southward with most of the
convection from around COU east through the St Louis metro area to
Vandalia and Salem IL by midnight. Some of these storms may be
severe due to very unstable conditions late this afternoon and this
evening with CAPEs of 2000-3000 J/Kg and surface LI values as low as
-10 south of the cold front. Low-mid level shear will also be
relatively strong with 500 mb wind speeds of up to 50 kts due to a
500 mb wind max moving through the Great Lakes region.
GKS
.LONG TERM: (Thursday through Next Wednesday)
Issued at 340 PM CDT Wed May 21 2014
The cold front will continue to sag slowly southward as a surface
ridge shifts eastward from the northern Plains into the Great Lakes
region. At least scattered convection is expected along and just
behind this front as weak shortwaves move east southeastward through
our area over the mid-upper level ridge centered over the Gulf Coast
states. The best coverage of convection should be across central
and southeast MO Thursday and Thursday night as the front becomes
more nw to se oriented. The ECMWF model appears to be a little too
far north with its qpf from Thursday afternoon into Friday morning.
Cooler and drier air will advect into the region behind the cold
front, particularly across northeast MO and west central IL.
The mid-upper level low now over NV will move slowly through the
southwest US. Weak shortwaves will eject northeastward from this
feature and bring more convection mainly to the western portion of
our forecast area Saturday and Saturday night with the upper level
ridge along with the surface ridge centered over the Great Lakes and
Ohio Valley regions keeping the eastern portion of our forecast area
dry. The mid-upper level low will eventually move into the Plains
by Monday. The models have varying solutions after this with the
ECMWF model moving it into MO by Tuesday, while the GFS model
weakens it and has it passing south of our area. With this model
uncertainty will just include chance pops for early next week,
although there may be more widespread showers/storms for Monday
night and Tuesday. Always difficult to forecast the exact path,
strength and speed of upper level lows coming out of the southwest
US.
GKS
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1124 PM CDT Wed May 21 2014
Thunderstorms have diminished from earlier this evening leaving
just a few lingering showers over west central Illinois. Cold
front is now between KUIN and KCOU and the St. Louis metro TAF
sites. It will continue to move south the next few hours before
stalling overnight into Friday over southern and western Missouri.
Expect mainly dry and VFR conditions during this TAF period with
north to northeast winds to the north of the cold front. The only
exception may be at KCOU tomorrow afternoon and evening when
scattered thunderstorm may develop close enough to the airport
that they could affect the terminal. Confidence in this scenario
is not high enough to even mention VCTS at this point.
Specifics for KSTL:
Expect dry and VFR conditions through the TAF period.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
904 PM MDT FRI MAY 23 2014
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SUNDAY...
UPDATE...ADJUSTED THUNDERSHOWER COVERAGE IN THE SOUTHEAST THROUGH
MIDNIGHT AS AN AREA OF PRECIPITATION WITH EMBEDDED THUNDER
CONTINUES OVER THAT REGION. ELSEWHERE ISOLATED SHOWERS AND
THUNDERSTORMS REMAIN POSSIBLE WITH ALL KINDS OF BOUNDARIES
DEVELOPING ACROSS THE REGION. THE HRRR HAS THE CLUSTER OF SHOWERS
AND THUNDERSTORMS EAST OF GREAT FALLS CURRENTLY MAKING IT INTO THE
FAR WESTERN ZONES AFTER MIDNIGHT. KEPT POPS UP IN THAT AREA
OVERNIGHT TO HANDLE THAT POSSIBILITY. PROTON
THE ATMOSPHERE HAS DESTABILIZED AS PER CUMULUS BUILDUPS EVIDENT
ON VISIBLE SATELLITE...AND ISOLATED THUNDERSTORMS EVIDENT ON
RADAR. THUS EXPECT ISOLATED THUNDERSTORMS THIS EVENING...WITH MORE
SCATTERED STORMS ALONG A WINNETT TO GLASGOW LINE. AFTER MIDNIGHT
AN APPROACHING SHORTWAVE FEATURE COULD DRIVE A FEW SHOWERS AND
THUNDERSTORMS...MAINLY CENTERED OVER PHILLIPS COUNTY.
SATURDAY A COLD FRONT ON THE BACK SIDE OF A SURFACE TROUGH PUSHING
THROUGH NORTHEAST MONTANA WILL SERVE AS A FOCUS FOR CONVECTION...PUSHING
FROM WEST TO EAST THROUGH THE AFTERNOON AND EVENING HOURS. SHEAR
BECOMES MORE FAVORABLE FOR ORGANIZED CONVECTION...THUS STORMS
DURING THE AFTERNOON AND EVENING COULD BE STRONG TO SEVERE IN
NATURE. WILL RAMP UP WORDING TO INCLUDE GUSTY WINDS AND SMALL HAIL
AND CONTINUE THE HAZARDOUS WEATHER OUTLOOK FOR NOW.
SUNDAY THE SURFACE FRONT WILL HAVE PUSHED OUT OF THE AREA. SOME
LINGERING SHOWERS AND OR THUNDERSTORMS WILL BE PRESENT ACROSS THE
EAST DURING THE MORNING...BUT BY THE AFTERNOON SUBSIDENCE FROM
UPPER LEVEL AND MIDLEVEL RIDGING WILL CAP PRECIPITATION POTENTIAL.
TEMPERATURES FOR SUNDAY WILL BE COOLER THEN SATURDAYS HIGHS...BUT
STILL WELL ABOVE NORMALS. GILCHRIST
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
AS NOTED IN THE PREVIOUS DISCUSSION...NORTHEAST MONTANA WILL BE
UNDER SOUTHWEST FLOW ALOFT FOR THE ENTIRE EXTENDED PERIOD. WITH
THIS SETUP...AFTERNOON AND EARLY EVENING THUNDERSTORMS WILL BECOME
ROUTINE WITH EVERY DISTURBANCE THAT COMES ALONG. THE SOUTHWEST
FLOW WILL ALSO RAMP TEMPERATURES UP TO OR ABOVE NORMAL THROUGH THE
WEEK.
A TROUGH OFF THE NORTHWEST COAST WILL SLOWLY MOVE EAST INTO THE
INTER-MOUNTAIN WEST BY MID WEEK. THE FIRST PERIOD WITH AN ENHANCED
CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE MONDAY AFTERNOON AND
MONDAY NIGHT AS A COLD FRONT ASSOCIATED WITH THE TROUGH NUDGES
CLOSER. THEN MOST EVERY PERIOD THAT FOLLOWS WILL HAVE A CHANCE TO
PRODUCE SHOWERS AND THUNDER. CHANGES WERE TO INCREASE POPS. SCT
PREVIOUS DISCUSSION...
UPPER LOW OVER THE DESERT SOUTHWEST WILL SLOWLY MEANDER INTO THE
SOUTHERN PLAINS OVER THE NEXT WEEK. ANOTHER UPPER TROUGH WILL DROP
OUT OF THE GULF OF ALASKA AND SETTLE IN OVER THE PACIFIC NORTHWEST
BY SUNDAY. THE RESULT WILL BE WARM SOUTHWEST FLOW INTO EASTERN
MONTANA FOR THE EXTENDED PERIOD. WITH SEVERAL SHORTWAVES MOVING
ACROSS THE REGION...THERE WILL BE CHANCES FOR SHOWERS AND
THUNDERSTORMS ALMOST EVERY DAY. THERE WILL BE SOME DRY PERIODS IN
BETWEEN WAVES BUT TIMING THESE CAN BE DIFFICULT SEVERAL DAYS OUT.
WILL GENERALLY BROAD-BRUSH A CHANCE/SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS. FORRESTER
&&
.AVIATION...
THUNDERSTORM ACTIVITY CONTINUES THIS EVENING...MAINLY AROUND KGDV
AND KSDY. STORMS SHOULD WEAKEN TONIGHT BEFORE ANOTHER ROUND OF
STORMS MAY POP UP TOMORROW AFTERNOON AND EVENING. SHOWERS MAY MOVE
IN FROM THE WEST OVERNIGHT INTO SATURDAY MORNING AS WELL. EAST AND
SOUTHEAST WINDS THIS EVENING OF 10 TO 15 KNOTS SHOULD BECOME LIGHT
AND VARIABLE OVERNIGHT. BARNWELL
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
342 PM CDT THU MAY 22 2014
.SYNOPSIS...
ISSUED AT 342 PM CDT THU MAY 22 2014
THE H5 PATTERN REMAINS LARGELY UNCHANGED FROM 24 HOURS
AGO WITH LITTLE OR NO HT CHANGES NOTED ACROSS THE CONUS. HIGH
PRESSURE WAS ANCHORED OVER SERN ALABAMA...WITH LOW PRESSURE OVER THE
CANADIAN MARITIMES AND A CLOSED LOW OVER THE CALIFORNIA DESERT. WV
IMAGERY THIS AFTERNOON HAS A DECENT SHORTWAVE LIFTING NORTH ACROSS
THE SRN ROCKIES FROM NRN NEW MEXICO INTO SRN COLORADO. ANOTHER
SHORTWAVE WAS LIFTING ACROSS EASTERN UT AND WESTERN WYOMING AS OF
MIDDAY. FURTHER EAST...THE REMNANTS OF A CONVECTIVE COMPLEX WHICH
LIFTED ACROSS SRN NEBRASKA AND NORTHERN KS OVERNIGHT...HAS LIFTED
EAST INTO THE MID MISSISSIPPI VALLEY. AT THE SURFACE...A STATIONARY
FRONT EXTENDED FROM NEAR SAINT LOUIS MO...WSW INTO THE OK
PANHANDLE...THEN NNWD ALONG THE FRONT RANGE OF COLORADO AND WYOMING.
FURTHER NORTH...HIGH PRESSURE HAS MOVED FROM THE DAKOTAS INTO THE
UPPER MISSISSIPPI VALLEY THIS MORNING...WHICH HAS SHIFTED WINDS TO A
MORE SERLY DIRECTION THIS MORNING...AND HAS BEGUN TO PUSH ADDITIONAL
LOW LEVL MOISTURE INTO WESTERN AND NORTH CENTRAL NEBRASKA. AS OF 2
PM CDT...UNDER PARTLY CLOUDY SKIES...TEMPERATURES RANGED FROM 73 TO
75 DEGREES ACROSS WESTERN AND NORTH CENTRAL NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 342 PM CDT THU MAY 22 2014
UPPER LEVEL RIDGE REMAINS PARKED ACROSS MUCH OF THE CENTRAL UNITED
STATES ONCE AGAIN TODAY...EFFECTIVELY IMPEDING THE UPPER FLOW OVER
MUCH OF THE CONUS. WITH THIS BLOCKED FLOW...THE UPPER LEVEL LOW OFF
TO OUR WEST HAS NOT MADE SIGNIFICANT EASTWARD PROGRESS OVER THE PAST
24 HOURS...BUT HAS SLIPPED SOUTH INTO SOUTHERN CALI/NORTHERN BAJA.
THIS SOUTHWARD SHIFT HAS ALLOWED FOR A SLIGHT AMPLIFICATION OF THE
RIDGE INTO THE WESTERN HIGH PLAINS...WHICH IS NOW PROVIDING FOR A
LIGHTER...BUT MORE DIRECT NORTHERLY COMPONENT OF THE STEERING LEVEL
WINDS. AS HAS BEEN THE CASE THE PAST FEW DAYS...THE CONVECTION
ALLOWING MODELS ARE GENERATING CONVECTION NEAR THE FRONT
RANGE/PALMER DIVIDE AND ALONG CONVERGENCE ASSOCIATED WITH A MODEST
DCVZ. WITH TIME THE MODELS INDICATE ADDITIONAL DEVELOPMENT FURTHER
EAST ON THE HIGH PLAINS AS THE ATMOSPHERE CONTINUES TO DESTABILIZE
IN A WEAK LOW LEVEL UPSLOPE REGIME. THIS ACTIVITY IS SHOWN TO SPILL
ONTO THE PLAINS OF FAR SOUTHWEST AND WESTERN NEBRASKA THIS EVENING
DESPITE THE GREATER NORTHERLY TRAJECTORY. THE HRRR HAS HANDLED THE
PAST FEW DAYS WELL ALONG THE FRONT RANGE AND ADJACENT PLAINS...THUS
THE FORECAST THROUGH INTO THE OVERNIGHT WAS TRENDED IN THAT
DIRECTION. WITH THAT...GENERALLY CUT BACK THE EXTENT AND
PROBABILITY OF PRECIP FOR MUCH OF THE CWA...SAVE FOR OUR FAR
SOUTHWEST WHERE THE RAP13 AND HRRR SUGGEST THE PRESENCE OF STORMS
AFTER 03Z. SHOULD STORMS HOLD TOGETHER INTO SOUTHWEST NEBRASKA THIS
EVENING THERE IS SOME SUPPORT OF ELEVATED INSTABILITY WHICH WOULD
PROMOTE A STRONG TO SEVERE STORM OR TWO. OTHERWISE INCREASING
CLOUDS OVERNIGHT WILL HELP KEEP TEMPERATURES MILD...WIDESPREAD LOWS
IN THE MID 50S SEEMS PLAUSIBLE.
FRIDAY...SURFACE HIGH PRESSURE WILL BUILD EAST TOWARD THE GREAT
LAKES REGION...ALLOWING FOR A GREATER SOUTHERLY COMPONENT TO THE
LOWER TROPOSPHERIC FLOW ACROSS THE CWA. WITH INCREASING LOW LEVEL
MOISTURE...SHOWERS AND THUNDERSTORMS WILL FORM WITH A LIFTING
FRONTAL BOUNDARY BY EARLY AFTERNOON. THE CAPPING INVERSION IS WEAK
FRIDAY...SO STORM COVERAGE IS EXPECTED TO BE MORE NUMEROUS...BUT
SEVERE COVERAGE SHOULD BE LIMITED AS NUMEROUS UPDRAFTS COMPETE AND
THE UPPER STEERING FLOW REMAINS WEAK UNDER RIDGING ALOFT.
TEMPERATURES WILL BE MODERATED BY EXPECTED OVERCAST SKIES AND THE
POTENTIAL OF SHOWERS. HIGHS IN THE 70S FOR MOST LOCATIONS SEEMS ON
PAR.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 PM CDT THU MAY 22 2014
FRIDAY NIGHT THROUGH MONDAY...FORECASTING CHALLENGES IN
THE MID RANGE CONTINUE TO BE PRECIPITATION CHANCES...AS A PERSISTENT
TROUGH OF LOW PRESSURE ALOFT CREEPS TOWARD THE CENTRAL AND SOUTHERN
PLAINS INTO THE WEEKEND. ONGOING CONVECTION ACROSS NERN COLORADO AND
WESTERN KS...WILL MAKE ITS WAY INTO SOUTHWESTERN AND WESTERN
NEBRASKA FRIDAY EVENING. AS HAS BEEN THE CASE OVER THE PAST SEVERAL
NIGHTS...THIS ACTIVITY IS EXPECTED TO WEAKEN AS IT MOVES EAST INTO
MUCH WEAKER SHEAR ACROSS WESTERN NEBRASKA. CHANCE POPS WERE
CONTINUED IN THE WEST AND SWRN CWA FRIDAY EVENING WITH POPS FALLING
SHARPLY IN THE CENTRAL AND EAST. EVEN WITH DECENT MOISTURE...THE
LACK OF A DECENT LOW LEVEL JET AND WEAK DYNAMICS SHOULD LIMIT THE
COVERAGE OF PCPN FRIDAY NIGHT. MIN TEMPS SATURDAY MORNING...ARE
EXPECTED TO BE MILD IN THE MID AND UPPER 50S GIVEN THE INCREASED LOW
LEVEL MOISTURE...AND EXPECTED LOW LEVEL CLOUD COVER. LOW CLOUDINESS
WILL LINGER INTO SATURDAY WITH THE MODELS INDICATING A CONTINUATION
OF PERSISTENT LOW LEVEL CLOUDINESS INTO SATURDAY AFTERNOON. WITH
AFTERNOON HEATING AND A WEAK CAP IN PLACE...AM EXPECTING SHOWERS AND
THUNDERSTORMS TO DEVELOP...ESPECIALLY OVER SWRN NEBRASKA WHERE
CAPE/S REACH 1000 TO 1500 J/KG SAT AFTERNOON. THIS ACTIVITY IS
EXPECTED TO BE FAIRLY DISORGANIZED THOUGH AS DEEP SHEAR IS VERY WEAK
AT 15 KTS OR LESS SAT AFTN AND SAT EVE. ON SATURDAY NIGHT...THE
FRONTAL BOUNDARY WILL LIFT NORTH INTO SOUTH DAKOTA. BY
SUNDAY...SHOWERS AND THUNDERSTORMS WILL DEVELOP ACROSS SOUTH DAKOTA
INVOF OF THE FRONT...AIDED BY A SHORTWAVE TROUGH WHICH TRAVERSES THE
NRN TIER OF STATES SUN AFTERNOON. FURTHER SOUTH...SHRAS AND
THUNDERSTORMS WILL DEVELOP ACROSS THE HIGH PLAINS OF WESTERN KANSAS
SOUTH TO THE TX PANHANDLE. IN ADVANCE OF THE MAIN UPPER LEVEL TROUGH
OF LOW PRESSURE. DECIDED TO DROP POPS DOWN A BIT FOR
SUNDAY...PARTICULARLY IN SWRN NEBRASKA...WITH THE BEST FORCING OVER
WRN KS...AND NORTH OF THE FORECAST AREA INVOF THE FRONT. BETTER
CHANCES FOR PCPN WILL ARRIVE IN ALL AREAS SUNDAY NIGHT INTO EARLY
MONDAY AS THE FRONT DROPS SOUTH INTO THE FORECAST AREA.
MONDAY NIGHT THROUGH THURSDAY...THE UPPER LEVEL TROUGH OF LOW
PRESSURE WILL LIFT EAST ACROSS THE SOUTHERN PLAINS MONDAY INTO
MONDAY NIGHT...SHIFTING THE THREAT FOR PCPN EAST. TEMPERATURES WILL
WARM WEDNESDAY AND THURSDAY THANKS TO WEAK LOW AMPLITUDE RIDGING
ACROSS THE ROCKIES. NO DOUBT...WE MAY SEE SOME ISOLATED
THUNDERSTORMS WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING TROUGH
OF LOW PRESSURE. WITH GUIDANCE POPS WELL BELOW CLIMO...WILL LEAVE
CONDS DRY FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1220 PM CDT THU MAY 22 2014
OR THE 18Z KLBF AND KVTN TAFS...CONVECTION CHANCES CONTINUES TO BE
THE MAIN FORECAST CONCERN TO THE AVIATION COMMUNITY. THE FORECAST
IS EMPLOYING A PERSISTENCE APPROACH CONCERNING THE
CONVECTION...THIS IS BASED OFF THE FACT THAT LITTLE CHANGE IN THE
UPPER PATTERN HAS BEEN NOTED OVER THE PAST 24 HRS. AS SEEN THE PAST
COUPLE DAYS...STORMS WILL INITIATE OFF THE PALMER DIVIDE AND/OR
HIGHER TERRAIN OF EASTERN COLORADO/WYOMING THIS AFTERNOON...THEN
SLOWLY MOVE/BUILD TO THE EAST NORTHEAST THROUGH THE AFTERNOON. THE
CONVECTION ALLOWING SHORT TERM MODELS SEEM TO BE OFF A BIT ON THE
TIMING AND LOCATIONS OF THE FRONT RANGE CONVECTION...AND THUS DOES
DEEMED SUSPECT. BUT THE GENERAL IDEA IS THAT THE EVENTUAL
CONVECTION WILL DRIFT INTO FAR SOUTHWEST NEBRASKA AFTER 00Z THIS
EVENING...POTENTIALLY IMPACTING THE KIML AND KOGA TERMINALS.
THERMODYNAMIC PROFILES DO NOT FAVOR WIDESPREAD SEVERE...BUT A STRONG
STORM OR TWO WOULD BE POSSIBLE. INTO THE OVERNIGHT AND FRIDAY...THE
UPPER LOW RESPONSIBLE FOR THE HIGH PLAINS CONVECTION THE PAST COUPLE
DAYS WILL FINALLY EJECT TO THE SOUTHEAST TOWARD THE SOUTHERN
PLAINS. AS THIS OCCURS A DISTURBANCE IS SHOWN TO ROTATE NORTH
ACROSS THE HIGH PLAINS ALLOWING FOR GREATER COVERAGE OF -TSRA TO
THE REGION. ATTM THE GREATEST COVERAGE BEFORE 18Z WILL BE ACROSS
SOUTHWEST NEBRASKA...POSSIBLY AS FAR NORTH AS KLBF.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...JACOBS
LONG TERM...JACOBS
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
107 PM CDT THU MAY 22 2014
.UPDATE...
ISSUED AT 459 AM CDT THU MAY 22 2014
ALREADY SENDING AN UPDATE TO ACCOUNT FOR THE LIFT GENERATING NEW
SHWRS BETWEEN MCK-IML-AKO. THE PUB/GLD RADARS SHOW 25-30 KTS FROM
THE SW AT 5K FT AGL. THE NAM/GFS DO INDICATE ISENTROPIC LIFT WHERE
THESE SHWRS ARE DEVELOPING. NOT SURE HOW MUCH OF THIS WILL HEAD E
INTO THE FCST AREA. SO POPS HAVE BEEN INCREASED THIS MORNING AND
ANTICIPATE FURTHER SHORT-TERM ADJUSTMENTS AS THE MORNING PROCEEDS.
IRONICALLY I USED THE 06Z NAM AS A GUIDE. IF THE NAM TURNS OUT
CORRECT...MAJOR FCST ADJUSTMENTS WILL BE NEEDED LATER THIS
MORNING. WE HAVE NOTED SEVERAL MODELS CAP HIGH TEMPS IN THE UPPER
60S OVER MUCH OF S-CNTRL NEB.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU MAY 22 2014
...A DIFFICULT FCST THRU TONIGHT WITH BELOW AVERAGE CONFIDENCE
DUE TO POOR MODEL HANDLING OF THE PLETHORA OF MESOSCALE ASPECTS...
ALOFT: THE LONGWAVES ARE ESSENTIALLY STAGNANT OVER THE CONUS. A
588 SUB-TROPICAL HIGH WAS OVER THE GULF COAST STATES AND WILL
REMAIN THERE THRU TONIGHT. ITS RIDGE AXIS WILL CONT TO EXTEND NW
ACROSS THE CNTRL PLAINS TO MT. THE CUT-OFF LOW OVER NV/CA WILL
MEANDER FURTHER S INTO AZ TONIGHT.
SURFACE: A COOL FRONT REMAINS STALLED W-E ACROSS KS AND WILL
REMAIN IN PLACE THRU AT LEAST TONIGHT. OVERNIGHT TSTM ACTIVITY
WILL STRENGTHEN THE FRONT TODAY. NRN PLAINS HIGH PRES WILL DRIFT
INTO THE WRN GREAT LAKES.
REST OF THIS MORNING: TSTM CLUSTERS WILL CONT EXITING INTO ERN
NEB/KS. CANT COMPLETELY RULE OUT A COUPLE MORE ISOLATED SHWRS/
TSTMS FROM DEVELOPING...BUT THE OVERALL TREND SHOULD BE DRIER.
THIS AGREES WITH THE 03Z HRRR AND 00Z HI-RES WRF RUNS.
QUIET SYNOPTIC REGIMES SUCH AS THIS CREATE MAJOR HEADACHES FOR
FCSTRS. A LOT OF IT COMES DOWN TO INTUITION AS MECHANISMS TO
TRIGGER TSTMS ARE SUBTLE. BUST POTENTIAL IS AT EVERY CORNER FOR
TEMPS/SKY/PRECIP.
TODAY: MOSTLY CLOUDY THIS MORNING WITH LOTS OF CLOUD DEBRIS
AROUND ...BUT IR SATELLITE SHOWS A CLEARING LINE ADVANCING UP FROM
THE TX PANHANDLE. THE TIME-OF-ARRIVAL TOOL BRINGS IT TO OUR SW
COUNTIES BY 830 AM AND TO OUR NE COUNTIES BY 130 PM. SO SKIES
SHOULD TURN PARTLY CLOUDY IF NOT MOSTLY SUNNY THIS AFTERNOON. THIS
BARRING ANY STRATUS THAT MIGHT FORM IN THE PREDAWN HOURS.
BEFORE THE TSTMS FIRED YESTERDAY AFTERNOON...WATER VAPOR IMAGERY
SHOWED WHAT APPEARED TO BE A SHORTWAVE TROF LIFTING FROM NM INTO
THE CNTRL PLAINS. THIS TROF SHOULD ROUND THE RIDGE WITH SUBSIDENCE
TO FOLLOW TODAY. THIS IS PROBABLY WHAT WE ARE SEEING WITH THAT
CLEARING LINE IN SATELLITE.
THE 00Z/06Z NAM CONVECTIVE SCHEMES RE-FIRE TSTMS BY MIDDAY
TODAY...BASICALLY AS SOON AS THE CONVECTIVE TEMP IS REACHED. I
JUST CANNOT SEE THAT HAPPENING IN THE WAKE OF THE DEPARTING TROF.
WOULD EXPECT SOME SUBSIDENCE INVERSION TO RESULT IN AT LEAST A
MODEST CAP. SO THE FCST IS DRY UNTIL 5PM WHEN SLIGHT CHANCE POPS
WERE BROUGHT INTO OUR N-CNTRL KS COUNTIES. HAVE FOLLOWED THE 00Z
WRF RUNS FROM THE NAM... THE NSSL WRF AND THE 07Z/08Z 13 KM RAP
WHICH DO NOT REFIRE CONVECTION.
OTHER MESOSCALE DETAILS: WITH THE HIGH DRIFTING FURTHER E...THE
E-W ORIENTED BAND OF RICH 850 MB MOISTURE ALONG THE FRONT WILL
BEGIN CIRCULATING NW...LIFTING INTO NEB. HOWEVER...SURFACE
DEWPOINTS UPSTREAM OVER IA WERE STILL IN THE MID 40S. SO WHILE IN
SITU DEWPOINTS HAVE RISEN OVERNIGHT...VERY LOW-LEVEL DRY AIR
ADVECTION WILL BE OCCURRING.
ISOLATED TSTMS COULD FIRE ALONG THE CONVECTIVELY REINFORCED WARM
FRONT OVER KS. THIS ACTIVITY COULD LIFT INTO OUR N-CNTRL KS
COUNTIES AND THIS IS WHAT IS FCST BY THE NON-HYDROSTATIC MODELS.
NAM PV IMAGES SHOW A SUBTLE SHORTWAVE TROF EMBEDDED IN THE DRY
SLOT CURRENTLY OVER AZ. MOVEMENT IS NNE AND IT IS FCST TO LIFT
ACROSS NM AND INTO CO TONIGHT. THIS SHOULD TRIGGER THE TSTMS LATE
THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS. WE THEN
ANTICIPATE THIS ACTIVITY TO THREATEN OR MOVE INTO THE FCST AREA
FROM THE SW AGAIN TONIGHT. NO GUARANTEES ON THIS THOUGH. SEVERAL
NON-HYDROSTATIC MODELS KEEP THE FCST AREA DRY. SO POPS WERE KEPT
LOW.
TONIGHT: INCREASING CLOUDS WITH A CHANCE OF SHWRS/TSTMS. GREATEST
CHANCE S AND W OF THE TRI-CITIES. EFFECTIVE SHEAR WILL BE AROUND
30 KTS. WHILE AN ISOLATED SEVERE TSTM IS POSSIBLE OVER N-CNTRL KS
BEFORE MIDNIGHT...IT IS LARGELY BASED ON "IF" TSTMS OCCUR AT ALL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 417 AM CDT THU MAY 22 2014
GUIDANCE SUGGESTS A CLOSED UPPER TROPOSPHERIC LOW WILL EXIST OVER
THE SOUTHWESTERN CONUS AT 12Z FRIDAY. THIS CLOSED LOW IS THEN
EXPECTED TO DRIFT TO THE NORTHEAST AND WEAKEN...EVENTUALLY MOVING
OVER THE CENTRAL PLAINS AS AN OPEN WAVE BY EARLY NEXT WEEK. AT THE
SURFACE SOUTH OR SOUTHEASTERLY FLOW IS EXPECTED TO PERSIST ACROSS
THE AREA THROUGH MUCH OF THE LONG TERM FORECAST PERIOD.
UPPER TROPOSPHERIC THERMAL ADVECTION AHEAD OF THE SOUTHWESTERN
UPPER TROPOSPHERIC CLOSED LOW...ALONG WITH MULTIPLE SUBTLE UPPER
TROPOSPHERIC PERTURBATIONS EJECTING FROM THE SOUTHWESTERN
CONUS...WILL CONTINUE TO PROMOTE CHANCES FOR PRECIPITATION ACROSS
THE CWA MOST EVERY DAY DURING THE LONG TERM FORECAST PERIOD. WENT
AHEAD AND TOOK AN EVEN BLEND OF NAM...OPERATIONAL GFS...EC...SREF-
MEAN AND WPC GUIDANCE TO DERIVE QPF GRIDS BOTH FRIDAY AND
SATURDAY...AND THEN DERIVED THE POP GRIDS FROM THESE QPF GRIDS.
AFTER ALL WAS SAID AND DONE...VERY LITTLE CHANGE WAS MADE TO THE
GOING FORECAST. OVERALL...30-60% POPS REMAIN INTACT FOR THE MOST
PART ACROSS THE CWA FRIDAY THROUGH SATURDAY NIGHT. SUNDAY AND
BEYOND...ALLBLEND PROVIDED 20-60% POPS TO VARIOUS PORTIONS OF THE
CWA DURING THE LONG TERM FORECAST PERIOD. THESE POPS WERE LEFT
UNCHANGED FOR THE MOST PART.
CONTINUED SOUTH/SOUTHEASTERLY LOWER TROPOSPHERIC FLOW SHOULD KEEP
INCREASED VALUES OF LOWER TROPOSPHERIC MOISTURE INTACT ACROSS THE
AREA THROUGH EARLY TO MID NEXT WEEK...THUS RESULTING IN 1000-
3000J/KG OF POTENTIAL INSTABILITY EACH AFTERNOON AND EVENING.
ALTHOUGH DEEP-LAYER BULK SHEAR WONT BE ANYTHING TO GET EXCITED
ABOUT...THE MAGNITUDE OF POTENTIAL INSTABILITY ALONE COULD BE
ENOUGH TO PROMOTE STRONG UPDRAFT PRODUCTION CAPABLE OF RESPECTABLE
HAIL SIZE AND PERHAPS DOWN-BURST WIND. THE INHERITED HWO ALREADY
HAD A MENTION OF STRONG STORMS EACH AFTERNOON AND EVENING AND AT
THIS TIME THERE REALLY IS NO REASON TO CHANGE THIS. AS A
RESULT...WENT AHEAD AND MENTIONED THE POSSIBILITY OF STRONG
THUNDERSTORMS EACH AFTERNOON AND EVENING FRIDAY THROUGH NEXT
WEDNESDAY.
LITTLE IF ANY CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL
PRESENT SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE
LONG TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 70S AND
80S AND LOWS IN THE 50S AND 60S CURRENTLY FORECAST.
&&
.AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1235 PM CDT THU MAY 22 2014
PREVAILING VFR CONDITIONS ARE EXPECTED AT KGRI THROUGH THE
AFTERNOON HOURS...WITH THUNDERSTROMS EXPECTED TO DEVELOP OVER THE
HIGH PLAINS AND MOVE ACROSS THE REGION OVERNIGHT. DUE TO THE
UNCERTAINTY IN TIMING AND COVERAGE...OPTED TO ONLY INTRODUCE A
VCSH FOR THE TIME BEING. OTHERWISE...OUTSIDE OF ANY
THUNDERSTORMS...WINDS ARE EXPECTED TO BE LIGHT...GENERALLY EAST TO
SOUTHEASTERLY AT 12 KTS OR LESS THROUGH 23/15Z...WHEN THEY WILL
INCREASE A BIT...POTENTIALLY GUSTING TO NEAR 20 KTS TOMORROW
AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
636 AM CDT THU MAY 22 2014
.UPDATE...
ISSUED AT 459 AM CDT THU MAY 22 2014
ALREADY SENDING AN UPDATE TO ACCOUNT FOR THE LIFT GENERATING NEW
SHWRS BETWEEN MCK-IML-AKO. THE PUB/GLD RADARS SHOW 25-30 KTS FROM
THE SW AT 5K FT AGL. THE NAM/GFS DO INDICATE ISENTROPIC LIFT WHERE
THESE SHWRS ARE DEVELOPING. NOT SURE HOW MUCH OF THIS WILL HEAD E
INTO THE FCST AREA. SO POPS HAVE BEEN INCREASED THIS MORNING AND
ANTICIPATE FURTHER SHORT-TERM ADJUSTMENTS AS THE MORNING PROCEEDS.
IRONICALLY I USED THE 06Z NAM AS A GUIDE. IF THE NAM TURNS OUT
CORRECT...MAJOR FCST ADJUSTMENTS WILL BE NEEDED LATER THIS
MORNING. WE HAVE NOTED SEVERAL MODELS CAP HIGH TEMPS IN THE UPPER
60S OVER MUCH OF S-CNTRL NEB.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU MAY 22 2014
...A DIFFICULT FCST THRU TONIGHT WITH BELOW AVERAGE CONFIDENCE
DUE TO POOR MODEL HANDLING OF THE PLETHORA OF MESOSCALE ASPECTS...
ALOFT: THE LONGWAVES ARE ESSENTIALLY STAGNANT OVER THE CONUS. A
588 SUB-TROPICAL HIGH WAS OVER THE GULF COAST STATES AND WILL
REMAIN THERE THRU TONIGHT. ITS RIDGE AXIS WILL CONT TO EXTEND NW
ACROSS THE CNTRL PLAINS TO MT. THE CUT-OFF LOW OVER NV/CA WILL
MEANDER FURTHER S INTO AZ TONIGHT.
SURFACE: A COOL FRONT REMAINS STALLED W-E ACROSS KS AND WILL
REMAIN IN PLACE THRU AT LEAST TONIGHT. OVERNIGHT TSTM ACTIVITY
WILL STRENGTHEN THE FRONT TODAY. NRN PLAINS HIGH PRES WILL DRIFT
INTO THE WRN GREAT LAKES.
REST OF THIS MORNING: TSTM CLUSTERS WILL CONT EXITING INTO ERN
NEB/KS. CANT COMPLETELY RULE OUT A COUPLE MORE ISOLATED SHWRS/
TSTMS FROM DEVELOPING...BUT THE OVERALL TREND SHOULD BE DRIER.
THIS AGREES WITH THE 03Z HRRR AND 00Z HI-RES WRF RUNS.
QUIET SYNOPTIC REGIMES SUCH AS THIS CREATE MAJOR HEADACHES FOR
FCSTRS. A LOT OF IT COMES DOWN TO INTUITION AS MECHANISMS TO
TRIGGER TSTMS ARE SUBTLE. BUST POTENTIAL IS AT EVERY CORNER FOR
TEMPS/SKY/PRECIP.
TODAY: MOSTLY CLOUDY THIS MORNING WITH LOTS OF CLOUD DEBRIS
AROUND ...BUT IR SATELLITE SHOWS A CLEARING LINE ADVANCING UP FROM
THE TX PANHANDLE. THE TIME-OF-ARRIVAL TOOL BRINGS IT TO OUR SW
COUNTIES BY 830 AM AND TO OUR NE COUNTIES BY 130 PM. SO SKIES
SHOULD TURN PARTLY CLOUDY IF NOT MOSTLY SUNNY THIS AFTERNOON. THIS
BARRING ANY STRATUS THAT MIGHT FORM IN THE PREDAWN HOURS.
BEFORE THE TSTMS FIRED YESTERDAY AFTERNOON...WATER VAPOR IMAGERY
SHOWED WHAT APPEARED TO BE A SHORTWAVE TROF LIFTING FROM NM INTO
THE CNTRL PLAINS. THIS TROF SHOULD ROUND THE RIDGE WITH SUBSIDENCE
TO FOLLOW TODAY. THIS IS PROBABLY WHAT WE ARE SEEING WITH THAT
CLEARING LINE IN SATELLITE.
THE 00Z/06Z NAM CONVECTIVE SCHEMES RE-FIRE TSTMS BY MIDDAY
TODAY...BASICALLY AS SOON AS THE CONVECTIVE TEMP IS REACHED. I
JUST CANNOT SEE THAT HAPPENING IN THE WAKE OF THE DEPARTING TROF.
WOULD EXPECT SOME SUBSIDENCE INVERSION TO RESULT IN AT LEAST A
MODEST CAP. SO THE FCST IS DRY UNTIL 5PM WHEN SLIGHT CHANCE POPS
WERE BROUGHT INTO OUR N-CNTRL KS COUNTIES. HAVE FOLLOWED THE 00Z
WRF RUNS FROM THE NAM... THE NSSL WRF AND THE 07Z/08Z 13 KM RAP
WHICH DO NOT REFIRE CONVECTION.
OTHER MESOSCALE DETAILS: WITH THE HIGH DRIFTING FURTHER E...THE
E-W ORIENTED BAND OF RICH 850 MB MOISTURE ALONG THE FRONT WILL
BEGIN CIRCULATING NW...LIFTING INTO NEB. HOWEVER...SURFACE
DEWPOINTS UPSTREAM OVER IA WERE STILL IN THE MID 40S. SO WHILE IN
SITU DEWPOINTS HAVE RISEN OVERNIGHT...VERY LOW-LEVEL DRY AIR
ADVECTION WILL BE OCCURRING.
ISOLATED TSTMS COULD FIRE ALONG THE CONVECTIVELY REINFORCED WARM
FRONT OVER KS. THIS ACTIVITY COULD LIFT INTO OUR N-CNTRL KS
COUNTIES AND THIS IS WHAT IS FCST BY THE NON-HYDROSTATIC MODELS.
NAM PV IMAGES SHOW A SUBTLE SHORTWAVE TROF EMBEDDED IN THE DRY
SLOT CURRENTLY OVER AZ. MOVEMENT IS NNE AND IT IS FCST TO LIFT
ACROSS NM AND INTO CO TONIGHT. THIS SHOULD TRIGGER THE TSTMS LATE
THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS. WE THEN
ANTICIPATE THIS ACTIVITY TO THREATEN OR MOVE INTO THE FCST AREA
FROM THE SW AGAIN TONIGHT. NO GUARANTEES ON THIS THOUGH. SEVERAL
NON-HYDROSTATIC MODELS KEEP THE FCST AREA DRY. SO POPS WERE KEPT
LOW.
TONIGHT: INCREASING CLOUDS WITH A CHANCE OF SHWRS/TSTMS. GREATEST
CHANCE S AND W OF THE TRI-CITIES. EFFECTIVE SHEAR WILL BE AROUND
30 KTS. WHILE AN ISOLATED SEVERE TSTM IS POSSIBLE OVER N-CNTRL KS
BEFORE MIDNIGHT...IT IS LARGELY BASED ON "IF" TSTMS OCCUR AT ALL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 417 AM CDT THU MAY 22 2014
GUIDANCE SUGGESTS A CLOSED UPPER TROPOSPHERIC LOW WILL EXIST OVER
THE SOUTHWESTERN CONUS AT 12Z FRIDAY. THIS CLOSED LOW IS THEN
EXPECTED TO DRIFT TO THE NORTHEAST AND WEAKEN...EVENTUALLY MOVING
OVER THE CENTRAL PLAINS AS AN OPEN WAVE BY EARLY NEXT WEEK. AT THE
SURFACE SOUTH OR SOUTHEASTERLY FLOW IS EXPECTED TO PERSIST ACROSS
THE AREA THROUGH MUCH OF THE LONG TERM FORECAST PERIOD.
UPPER TROPOSPHERIC THERMAL ADVECTION AHEAD OF THE SOUTHWESTERN
UPPER TROPOSPHERIC CLOSED LOW...ALONG WITH MULTIPLE SUBTLE UPPER
TROPOSPHERIC PERTURBATIONS EJECTING FROM THE SOUTHWESTERN
CONUS...WILL CONTINUE TO PROMOTE CHANCES FOR PRECIPITATION ACROSS
THE CWA MOST EVERY DAY DURING THE LONG TERM FORECAST PERIOD. WENT
AHEAD AND TOOK AN EVEN BLEND OF NAM...OPERATIONAL GFS...EC...SREF-
MEAN AND WPC GUIDANCE TO DERIVE QPF GRIDS BOTH FRIDAY AND
SATURDAY...AND THEN DERIVED THE POP GRIDS FROM THESE QPF GRIDS.
AFTER ALL WAS SAID AND DONE...VERY LITTLE CHANGE WAS MADE TO THE
GOING FORECAST. OVERALL...30-60% POPS REMAIN INTACT FOR THE MOST
PART ACROSS THE CWA FRIDAY THROUGH SATURDAY NIGHT. SUNDAY AND
BEYOND...ALLBLEND PROVIDED 20-60% POPS TO VARIOUS PORTIONS OF THE
CWA DURING THE LONG TERM FORECAST PERIOD. THESE POPS WERE LEFT
UNCHANGED FOR THE MOST PART.
CONTINUED SOUTH/SOUTHEASTERLY LOWER TROPOSPHERIC FLOW SHOULD KEEP
INCREASED VALUES OF LOWER TROPOSPHERIC MOISTURE INTACT ACROSS THE
AREA THROUGH EARLY TO MID NEXT WEEK...THUS RESULTING IN 1000-
3000J/KG OF POTENTIAL INSTABILITY EACH AFTERNOON AND EVENING.
ALTHOUGH DEEP-LAYER BULK SHEAR WONT BE ANYTHING TO GET EXCITED
ABOUT...THE MAGNITUDE OF POTENTIAL INSTABILITY ALONE COULD BE
ENOUGH TO PROMOTE STRONG UPDRAFT PRODUCTION CAPABLE OF RESPECTABLE
HAIL SIZE AND PERHAPS DOWN-BURST WIND. THE INHERITED HWO ALREADY
HAD A MENTION OF STRONG STORMS EACH AFTERNOON AND EVENING AND AT
THIS TIME THERE REALLY IS NO REASON TO CHANGE THIS. AS A
RESULT...WENT AHEAD AND MENTIONED THE POSSIBILITY OF STRONG
THUNDERSTORMS EACH AFTERNOON AND EVENING FRIDAY THROUGH NEXT
WEDNESDAY.
LITTLE IF ANY CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL
PRESENT SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE
LONG TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 70S AND
80S AND LOWS IN THE 50S AND 60S CURRENTLY FORECAST.
&&
.AVIATION...(FOR THE 12Z GRI TAF THROUGH 12Z FRIDAY MORNING)
ISSUED AT 635 AM CDT THU MAY 22 2014
TODAY: VFR. RAIN SHOULD BE DONE FOR THE DAY. MULTI-LAYERED VFR
CEILINGS SHOULD CLEAR OUT WITH SCT CU DEVELOPING 16-18Z. E WINDS
WILL AVERAGE 10 KTS. CONFIDENCE: MEDIUM
TONIGHT: VFR THRU 06Z. TSTMS WILL ERUPT WELL TO THE W AND S OF THE
TERMINAL WHICH WILL SEND HIGH-LEVEL VFR CEILINGS BACK OVER GRI.
00Z AND 06Z GFS MOS AND THE BETTER-PERFORMING GFS LAMP GUIDANCE
BOTH INDICATE FLIGHT CONDITIONS WILL DECAY AFTER 06Z IN IFR
STRATUS AND MVFR FOG. FOR NOW WE HAVE HINTED AT THIS IN THE TAF.
WOULD LIKE TO SEE HOW FCST GUIDANCE EVOLVES THRU THE DAY BEFORE
BECOMING MORE PESSIMISTIC. A BAND OF RICH LOW-LEVEL MOISTURE
/CURRENTLY OVER KS/ WILL SPREAD N INTO NEB TONIGHT. THIS MAY BE
WHAT THE MODELS ARE KEYING ON. E WINDS WILL BE UNDER 10 KTS.
CONFIDENCE: MEDIUM BEFORE 06Z. LOW AFTER 06Z.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
459 AM CDT THU MAY 22 2014
.UPDATE...
ISSUED AT 459 AM CDT THU MAY 22 2014
ALREADY SENDING AN UPDATE TO ACCOUNT FOR THE LIFT GENERATING NEW
SHWRS BETWEEN MCK-IML-AKO. THE PUB/GLD RADARS SHOW 25-30 KTS FROM
THE SW AT 5K FT AGL. THE NAM/GFS DO INDICATE ISENTROPIC LIFT WHERE
THESE SHWRS ARE DEVELOPING. NOT SURE HOW MUCH OF THIS WILL HEAD E
INTO THE FCST AREA. SO POPS HAVE BEEN INCREASED THIS MORNING AND
ANTICIPATE FURTHER SHORT-TERM ADJUSTMENTS AS THE MORNING PROCEEDS.
IRONICALLY I USED THE 06Z NAM AS A GUIDE. IF THE NAM TURNS OUT
CORRECT...MAJOR FCST ADJUSTMENTS WILL BE NEEDED LATER THIS
MORNING. WE HAVE NOTED SEVERAL MODELS CAP HIGH TEMPS IN THE UPPER
60S OVER MUCH OF S-CNTRL NEB.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU MAY 22 2014
...A DIFFICULT FCST THRU TONIGHT WITH BELOW AVERAGE CONFIDENCE
DUE TO POOR MODEL HANDLING OF THE PLETHORA OF MESOSCALE ASPECTS...
ALOFT: THE LONGWAVES ARE ESSENTIALLY STAGNANT OVER THE CONUS. A
588 SUB-TROPICAL HIGH WAS OVER THE GULF COAST STATES AND WILL
REMAIN THERE THRU TONIGHT. ITS RIDGE AXIS WILL CONT TO EXTEND NW
ACROSS THE CNTRL PLAINS TO MT. THE CUT-OFF LOW OVER NV/CA WILL
MEANDER FURTHER S INTO AZ TONIGHT.
SURFACE: A COOL FRONT REMAINS STALLED W-E ACROSS KS AND WILL
REMAIN IN PLACE THRU AT LEAST TONIGHT. OVERNIGHT TSTM ACTIVITY
WILL STRENGTHEN THE FRONT TODAY. NRN PLAINS HIGH PRES WILL DRIFT
INTO THE WRN GREAT LAKES.
REST OF THIS MORNING: TSTM CLUSTERS WILL CONT EXITING INTO ERN
NEB/KS. CANT COMPLETELY RULE OUT A COUPLE MORE ISOLATED SHWRS/
TSTMS FROM DEVELOPING...BUT THE OVERALL TREND SHOULD BE DRIER.
THIS AGREES WITH THE 03Z HRRR AND 00Z HI-RES WRF RUNS.
QUIET SYNOPTIC REGIMES SUCH AS THIS CREATE MAJOR HEADACHES FOR
FCSTRS. A LOT OF IT COMES DOWN TO INTUITION AS MECHANISMS TO
TRIGGER TSTMS ARE SUBTLE. BUST POTENTIAL IS AT EVERY CORNER FOR
TEMPS/SKY/PRECIP.
TODAY: MOSTLY CLOUDY THIS MORNING WITH LOTS OF CLOUD DEBRIS
AROUND ...BUT IR SATELLITE SHOWS A CLEARING LINE ADVANCING UP FROM
THE TX PANHANDLE. THE TIME-OF-ARRIVAL TOOL BRINGS IT TO OUR SW
COUNTIES BY 830 AM AND TO OUR NE COUNTIES BY 130 PM. SO SKIES
SHOULD TURN PARTLY CLOUDY IF NOT MOSTLY SUNNY THIS AFTERNOON. THIS
BARRING ANY STRATUS THAT MIGHT FORM IN THE PREDAWN HOURS.
BEFORE THE TSTMS FIRED YESTERDAY AFTERNOON...WATER VAPOR IMAGERY
SHOWED WHAT APPEARED TO BE A SHORTWAVE TROF LIFTING FROM NM INTO
THE CNTRL PLAINS. THIS TROF SHOULD ROUND THE RIDGE WITH SUBSIDENCE
TO FOLLOW TODAY. THIS IS PROBABLY WHAT WE ARE SEEING WITH THAT
CLEARING LINE IN SATELLITE.
THE 00Z/06Z NAM CONVECTIVE SCHEMES RE-FIRE TSTMS BY MIDDAY
TODAY...BASICALLY AS SOON AS THE CONVECTIVE TEMP IS REACHED. I
JUST CANNOT SEE THAT HAPPENING IN THE WAKE OF THE DEPARTING TROF.
WOULD EXPECT SOME SUBSIDENCE INVERSION TO RESULT IN AT LEAST A
MODEST CAP. SO THE FCST IS DRY UNTIL 5PM WHEN SLIGHT CHANCE POPS
WERE BROUGHT INTO OUR N-CNTRL KS COUNTIES. HAVE FOLLOWED THE 00Z
WRF RUNS FROM THE NAM... THE NSSL WRF AND THE 07Z/08Z 13 KM RAP
WHICH DO NOT REFIRE CONVECTION.
OTHER MESOSCALE DETAILS: WITH THE HIGH DRIFTING FURTHER E...THE
E-W ORIENTED BAND OF RICH 850 MB MOISTURE ALONG THE FRONT WILL
BEGIN CIRCULATING NW...LIFTING INTO NEB. HOWEVER...SURFACE
DEWPOINTS UPSTREAM OVER IA WERE STILL IN THE MID 40S. SO WHILE IN
SITU DEWPOINTS HAVE RISEN OVERNIGHT...VERY LOW-LEVEL DRY AIR
ADVECTION WILL BE OCCURRING.
ISOLATED TSTMS COULD FIRE ALONG THE CONVECTIVELY REINFORCED WARM
FRONT OVER KS. THIS ACTIVITY COULD LIFT INTO OUR N-CNTRL KS
COUNTIES AND THIS IS WHAT IS FCST BY THE NON-HYDROSTATIC MODELS.
NAM PV IMAGES SHOW A SUBTLE SHORTWAVE TROF EMBEDDED IN THE DRY
SLOT CURRENTLY OVER AZ. MOVEMENT IS NNE AND IT IS FCST TO LIFT
ACROSS NM AND INTO CO TONIGHT. THIS SHOULD TRIGGER THE TSTMS LATE
THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS. WE THEN
ANTICIPATE THIS ACTIVITY TO THREATEN OR MOVE INTO THE FCST AREA
FROM THE SW AGAIN TONIGHT. NO GUARANTEES ON THIS THOUGH. SEVERAL
NON-HYDROSTATIC MODELS KEEP THE FCST AREA DRY. SO POPS WERE KEPT
LOW.
TONIGHT: INCREASING CLOUDS WITH A CHANCE OF SHWRS/TSTMS. GREATEST
CHANCE S AND W OF THE TRI-CITIES. EFFECTIVE SHEAR WILL BE AROUND
30 KTS. WHILE AN ISOLATED SEVERE TSTM IS POSSIBLE OVER N-CNTRL KS
BEFORE MIDNIGHT...IT IS LARGELY BASED ON "IF" TSTMS OCCUR AT ALL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 417 AM CDT THU MAY 22 2014
GUIDANCE SUGGESTS A CLOSED UPPER TROPOSPHERIC LOW WILL EXIST OVER
THE SOUTHWESTERN CONUS AT 12Z FRIDAY. THIS CLOSED LOW IS THEN
EXPECTED TO DRIFT TO THE NORTHEAST AND WEAKEN...EVENTUALLY MOVING
OVER THE CENTRAL PLAINS AS AN OPEN WAVE BY EARLY NEXT WEEK. AT THE
SURFACE SOUTH OR SOUTHEASTERLY FLOW IS EXPECTED TO PERSIST ACROSS
THE AREA THROUGH MUCH OF THE LONG TERM FORECAST PERIOD.
UPPER TROPOSPHERIC THERMAL ADVECTION AHEAD OF THE SOUTHWESTERN
UPPER TROPOSPHERIC CLOSED LOW...ALONG WITH MULTIPLE SUBTLE UPPER
TROPOSPHERIC PERTURBATIONS EJECTING FROM THE SOUTHWESTERN
CONUS...WILL CONTINUE TO PROMOTE CHANCES FOR PRECIPITATION ACROSS
THE CWA MOST EVERY DAY DURING THE LONG TERM FORECAST PERIOD. WENT
AHEAD AND TOOK AN EVEN BLEND OF NAM...OPERATIONAL GFS...EC...SREF-
MEAN AND WPC GUIDANCE TO DERIVE QPF GRIDS BOTH FRIDAY AND
SATURDAY...AND THEN DERIVED THE POP GRIDS FROM THESE QPF GRIDS.
AFTER ALL WAS SAID AND DONE...VERY LITTLE CHANGE WAS MADE TO THE
GOING FORECAST. OVERALL...30-60% POPS REMAIN INTACT FOR THE MOST
PART ACROSS THE CWA FRIDAY THROUGH SATURDAY NIGHT. SUNDAY AND
BEYOND...ALLBLEND PROVIDED 20-60% POPS TO VARIOUS PORTIONS OF THE
CWA DURING THE LONG TERM FORECAST PERIOD. THESE POPS WERE LEFT
UNCHANGED FOR THE MOST PART.
CONTINUED SOUTH/SOUTHEASTERLY LOWER TROPOSPHERIC FLOW SHOULD KEEP
INCREASED VALUES OF LOWER TROPOSPHERIC MOISTURE INTACT ACROSS THE
AREA THROUGH EARLY TO MID NEXT WEEK...THUS RESULTING IN 1000-
3000J/KG OF POTENTIAL INSTABILITY EACH AFTERNOON AND EVENING.
ALTHOUGH DEEP-LAYER BULK SHEAR WONT BE ANYTHING TO GET EXCITED
ABOUT...THE MAGNITUDE OF POTENTIAL INSTABILITY ALONE COULD BE
ENOUGH TO PROMOTE STRONG UPDRAFT PRODUCTION CAPABLE OF RESPECTABLE
HAIL SIZE AND PERHAPS DOWN-BURST WIND. THE INHERITED HWO ALREADY
HAD A MENTION OF STRONG STORMS EACH AFTERNOON AND EVENING AND AT
THIS TIME THERE REALLY IS NO REASON TO CHANGE THIS. AS A
RESULT...WENT AHEAD AND MENTIONED THE POSSIBILITY OF STRONG
THUNDERSTORMS EACH AFTERNOON AND EVENING FRIDAY THROUGH NEXT
WEDNESDAY.
LITTLE IF ANY CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL
PRESENT SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE
LONG TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 70S AND
80S AND LOWS IN THE 50S AND 60S CURRENTLY FORECAST.
&&
.AVIATION...(FOR THE 06Z GRI TAF THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1232 AM CDT THU MAY 22 2014
REST OF TONIGHT: MULTI-LAYERED VFR CLOUDS WILL INVADE AND DESCEND
WITH MVFR RAIN MOVING IN BY 08Z. CANT RULE OUT SOME THUNDER BUT
WILL AMEND THE TAF TO INCLUDE TSRA IF TRENDS WARRANT. WINDS WILL
REMAIN NE-ENE BELOW 10 KTS. CONFIDENCE: HIGH
THU: RAIN WILL END PRIOR TO DAYBREAK LEAVING VFR CONDITIONS. MOST
OF THE DAY SHOULD BE DRY. NOT SURE EXACTLY WHEN OR IF TSTMS WILL
REDEVELOP AS A FORCING MECHANISM IS LACKING. WINDS WILL SHIFT TO
THE E AROUND 10 KTS. CONFIDENCE: MEDIUM
THU EVE: VFR BUT THERE IS A CHANCE SHWRS/TSTMS COULD MOVE IN.
CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB 459
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
417 AM CDT THU MAY 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU MAY 22 2014
...A DIFFICULT FCST THRU TONIGHT WITH BELOW AVERAGE CONFIDENCE
DUE TO POOR MODEL HANDLING OF THE PLETHORA OF MESOSCALE ASPECTS...
ALOFT: THE LONGWAVES ARE ESSENTIALLY STAGNANT OVER THE CONUS. A
588 SUB-TROPICAL HIGH WAS OVER THE GULF COAST STATES AND WILL
REMAIN THERE THRU TONIGHT. ITS RIDGE AXIS WILL CONT TO EXTEND NW
ACROSS THE CNTRL PLAINS TO MT. THE CUT-OFF LOW OVER NV/CA WILL
MEANDER FURTHER S INTO AZ TONIGHT.
SURFACE: A COOL FRONT REMAINS STALLED W-E ACROSS KS AND WILL
REMAIN IN PLACE THRU AT LEAST TONIGHT. OVERNIGHT TSTM ACTIVITY
WILL STRENGTHEN THE FRONT TODAY. NRN PLAINS HIGH PRES WILL DRIFT
INTO THE WRN GREAT LAKES.
REST OF THIS MORNING: TSTM CLUSTERS WILL CONT EXITING INTO ERN
NEB/KS. CANT COMPLETELY RULE OUT A COUPLE MORE ISOLATED SHWRS/
TSTMS FROM DEVELOPING...BUT THE OVERALL TREND SHOULD BE DRIER.
THIS AGREES WITH THE 03Z HRRR AND 00Z HI-RES WRF RUNS.
QUIET SYNOPTIC REGIMES SUCH AS THIS CREATE MAJOR HEADACHES FOR
FCSTRS. A LOT OF IT COMES DOWN TO INTUITION AS MECHANISMS TO
TRIGGER TSTMS ARE SUBTLE. BUST POTENTIAL IS AT EVERY CORNER FOR
TEMPS/SKY/PRECIP.
TODAY: MOSTLY CLOUDY THIS MORNING WITH LOTS OF CLOUD DEBRIS
AROUND ...BUT IR SATELLITE SHOWS A CLEARING LINE ADVANCING UP FROM
THE TX PANHANDLE. THE TIME-OF-ARRIVAL TOOL BRINGS IT TO OUR SW
COUNTIES BY 830 AM AND TO OUR NE COUNTIES BY 130 PM. SO SKIES
SHOULD TURN PARTLY CLOUDY IF NOT MOSTLY SUNNY THIS AFTERNOON. THIS
BARRING ANY STRATUS THAT MIGHT FORM IN THE PREDAWN HOURS.
BEFORE THE TSTMS FIRED YESTERDAY AFTERNOON...WATER VAPOR IMAGERY
SHOWED WHAT APPEARED TO BE A SHORTWAVE TROF LIFTING FROM NM INTO
THE CNTRL PLAINS. THIS TROF SHOULD ROUND THE RIDGE WITH SUBSIDENCE
TO FOLLOW TODAY. THIS IS PROBABLY WHAT WE ARE SEEING WITH THAT
CLEARING LINE IN SATELLITE.
THE 00Z/06Z NAM CONVECTIVE SCHEMES RE-FIRE TSTMS BY MIDDAY
TODAY...BASICALLY AS SOON AS THE CONVECTIVE TEMP IS REACHED. I
JUST CANNOT SEE THAT HAPPENING IN THE WAKE OF THE DEPARTING TROF.
WOULD EXPECT SOME SUBSIDENCE INVERSION TO RESULT IN AT LEAST A
MODEST CAP. SO THE FCST IS DRY UNTIL 5PM WHEN SLIGHT CHANCE POPS
WERE BROUGHT INTO OUR N-CNTRL KS COUNTIES. HAVE FOLLOWED THE 00Z
WRF RUNS FROM THE NAM... THE NSSL WRF AND THE 07Z/08Z 13 KM RAP
WHICH DO NOT REFIRE CONVECTION.
OTHER MESOSCALE DETAILS: WITH THE HIGH DRIFTING FURTHER E...THE
E-W ORIENTED BAND OF RICH 850 MB MOISTURE ALONG THE FRONT WILL
BEGIN CIRCULATING NW...LIFTING INTO NEB. HOWEVER...SURFACE
DEWPOINTS UPSTREAM OVER IA WERE STILL IN THE MID 40S. SO WHILE IN
SITU DEWPOINTS HAVE RISEN OVERNIGHT...VERY LOW-LEVEL DRY AIR
ADVECTION WILL BE OCCURRING.
ISOLATED TSTMS COULD FIRE ALONG THE CONVECTIVELY REINFORCED WARM
FRONT OVER KS. THIS ACTIVITY COULD LIFT INTO OUR N-CNTRL KS
COUNTIES AND THIS IS WHAT IS FCST BY THE NON-HYDROSTATIC MODELS.
NAM PV IMAGES SHOW A SUBTLE SHORTWAVE TROF EMBEDDED IN THE DRY
SLOT CURRENTLY OVER AZ. MOVEMENT IS NNE AND IT IS FCST TO LIFT
ACROSS NM AND INTO CO TONIGHT. THIS SHOULD TRIGGER THE TSTMS LATE
THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS. WE THEN
ANTICIPATE THIS ACTIVITY TO THREATEN OR MOVE INTO THE FCST AREA
FROM THE SW AGAIN TONIGHT. NO GUARANTEES ON THIS THOUGH. SEVERAL
NON-HYDROSTATIC MODELS KEEP THE FCST AREA DRY. SO POPS WERE KEPT
LOW.
TONIGHT: INCREASING CLOUDS WITH A CHANCE OF SHWRS/TSTMS. GREATEST
CHANCE S AND W OF THE TRI-CITIES. EFFECTIVE SHEAR WILL BE AROUND
30 KTS. WHILE AN ISOLATED SEVERE TSTM IS POSSIBLE OVER N-CNTRL KS
BEFORE MIDNIGHT...IT IS LARGELY BASED ON "IF" TSTMS OCCUR AT ALL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 417 AM CDT THU MAY 22 2014
GUIDANCE SUGGESTS A CLOSED UPPER TROPOSPHERIC LOW WILL EXIST OVER
THE SOUTHWESTERN CONUS AT 12Z FRIDAY. THIS CLOSED LOW IS THEN
EXPECTED TO DRIFT TO THE NORTHEAST AND WEAKEN...EVENTUALLY MOVING
OVER THE CENTRAL PLAINS AS AN OPEN WAVE BY EARLY NEXT WEEK. AT THE
SURFACE SOUTH OR SOUTHEASTERLY FLOW IS EXPECTED TO PERSIST ACROSS
THE AREA THROUGH MUCH OF THE LONG TERM FORECAST PERIOD.
UPPER TROPOSPHERIC THERMAL ADVECTION AHEAD OF THE SOUTHWESTERN
UPPER TROPOSPHERIC CLOSED LOW...ALONG WITH MULTIPLE SUBTLE UPPER
TROPOSPHERIC PERTURBATIONS EJECTING FROM THE SOUTHWESTERN
CONUS...WILL CONTINUE TO PROMOTE CHANCES FOR PRECIPITATION ACROSS
THE CWA MOST EVERY DAY DURING THE LONG TERM FORECAST PERIOD. WENT
AHEAD AND TOOK AN EVEN BLEND OF NAM...OPERATIONAL GFS...EC...SREF-
MEAN AND WPC GUIDANCE TO DERIVE QPF GRIDS BOTH FRIDAY AND
SATURDAY...AND THEN DERIVED THE POP GRIDS FROM THESE QPF GRIDS.
AFTER ALL WAS SAID AND DONE...VERY LITTLE CHANGE WAS MADE TO THE
GOING FORECAST. OVERALL...30-60% POPS REMAIN INTACT FOR THE MOST
PART ACROSS THE CWA FRIDAY THROUGH SATURDAY NIGHT. SUNDAY AND
BEYOND...ALLBLEND PROVIDED 20-60% POPS TO VARIOUS PORTIONS OF THE
CWA DURING THE LONG TERM FORECAST PERIOD. THESE POPS WERE LEFT
UNCHANGED FOR THE MOST PART.
CONTINUED SOUTH/SOUTHEASTERLY LOWER TROPOSPHERIC FLOW SHOULD KEEP
INCREASED VALUES OF LOWER TROPOSPHERIC MOISTURE INTACT ACROSS THE
AREA THROUGH EARLY TO MID NEXT WEEK...THUS RESULTING IN 1000-
3000J/KG OF POTENTIAL INSTABILITY EACH AFTERNOON AND EVENING.
ALTHOUGH DEEP-LAYER BULK SHEAR WONT BE ANYTHING TO GET EXCITED
ABOUT...THE MAGNITUDE OF POTENTIAL INSTABILITY ALONE COULD BE
ENOUGH TO PROMOTE STRONG UPDRAFT PRODUCTION CAPABLE OF RESPECTABLE
HAIL SIZE AND PERHAPS DOWN-BURST WIND. THE INHERITED HWO ALREADY
HAD A MENTION OF STRONG STORMS EACH AFTERNOON AND EVENING AND AT
THIS TIME THERE REALLY IS NO REASON TO CHANGE THIS. AS A
RESULT...WENT AHEAD AND MENTIONED THE POSSIBILITY OF STRONG
THUNDERSTORMS EACH AFTERNOON AND EVENING FRIDAY THROUGH NEXT
WEDNESDAY.
LITTLE IF ANY CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL
PRESENT SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE
LONG TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 70S AND
80S AND LOWS IN THE 50S AND 60S CURRENTLY FORECAST.
&&
.AVIATION...(FOR THE 06Z GRI TAF THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1232 AM CDT THU MAY 22 2014
REST OF TONIGHT: MULTI-LAYERED VFR CLOUDS WILL INVADE AND DESCEND
WITH MVFR RAIN MOVING IN BY 08Z. CANT RULE OUT SOME THUNDER BUT
WILL AMEND THE TAF TO INCLUDE TSRA IF TRENDS WARRANT. WINDS WILL
REMAIN NE-ENE BELOW 10 KTS. CONFIDENCE: HIGH
THU: RAIN WILL END PRIOR TO DAYBREAK LEAVING VFR CONDITIONS. MOST
OF THE DAY SHOULD BE DRY. NOT SURE EXACTLY WHEN OR IF TSTMS WILL
REDEVELOP AS A FORCING MECHANISM IS LACKING. WINDS WILL SHIFT TO
THE E AROUND 10 KTS. CONFIDENCE: MEDIUM
THU EVE: VFR BUT THERE IS A CHANCE SHWRS/TSTMS COULD MOVE IN.
CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...BRYANT
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
351 AM CDT THU MAY 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT THU MAY 22 2014
A CLOSED UPPER LOW WAS LOCATED IN SRN CALIF/SWRN NV EARLY THIS
MORNING WITH UPSTREAM RIDING FROM THE LOWER MISSISSIPPI VALLEY
NORTHWESTWARD INTO WYOMING. MAIN AREA OF CONVECTION FROM NCTRL
KANSAS INTO CENTRAL NEBRASKA WILL CONTINUE TO MOVE NORTHEAST PRIOR
TO 12Z. THERE APPEAR TO BE A SHORTWAVE MOVING INTO EAST CENTRAL
CO...WHICH IS HELPING TO MAINTAIN AND DEVELOP SHOWERS AND A FEW
THUNDERSTORMS IN NERN CO INTO FAR SOUTHERN NEBR PNHDLE AND FAR SWRN
NEBR. WILL KEEP A 20 TO 30 PERCENT CHANCE FOR SHOWERS AND ISOLATED
THUNDERSTORMS MAINLY WEST OF MERRIMAN THROUGH NORTH PLATTE THIS
MORNING.
OVERALL UPSLOPE FLOW CONTINUES ACROSS THE CENTRAL PLAINS AND INTO
THE FOOTHILLS OF COLORADO AND EASTERN WYOMING TODAY. HIGHS TODAY
FROM 74 TO 80 DEGREES TO BE HINDERED SLIGHTLY BY CONTINUED UPSLOPE
LOW LEVEL WIND FLOW AND PARTLY TO AT TIMES MOSTLY CLOUDY SKIES
TODAY. WILL SEE AN UPTICK IN DEWPOINTS TODAY TO THE MID 50S AIDED BY
SOUTHEASTERLY SFC WINDS. BY LATE AFTERNOON...GREATEST INSTABILITY
AXIS TO RUN FROM CHEYENNE WY THROUGH AKRON CO AND GOODLAND KS.
STRONG TO SEVERE STORMS SHOULD DEVELOP ACROSS THIS AREA THIS
AFTERNOON AND DRIFT SLOWLY NORTHEAST TONIGHT. OTHER SHOWERS AND
THUNDERSTORMS ALSO POSSIBLE OR ONGOING IN WESTERN NEBRASKA THIS
AFTERNOON AND TONIGHT...ALTHOUGH ORGANIZED CLUSTER SHOULD RESIDE
FROM NERN CO INTO NWRN KANSAS AND POSSIBLY INTO SWRN NEBR TONIGHT.
HAVE THE HIGHEST POPS NEAR 50 PERCENT FOR SWRN NEBR AND BRING A
SLIGHT CHC TO NERN AREAS LATE TONIGHT. A FEW STORMS COULD BECOME
SEVERE BY EARLY EVENING SOUTHWEST OF CHAPPELL THROUGH HAYES CENTER.
OTHERWISE LOWS TONIGHT SHOULD RANGE IN THE MID AND UPPER 50S UNDER
MOSTLY CLOUDY SKIES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU MAY 22 2014
AN UPPER LEVEL AREA OF LOW PRESSURE WILL SLOWLY TRACK FROM THE
DESERT SOUTHWEST TO THE MID MISSISSIPPI VALLEY THROUGH THE PERIOD.
THIS WILL BE A VERY SLOW MOVING SYSTEM...WITH ABUNDANT LOW LEVEL
GULF MOISTURE PUSHING NORTHWARD INTO THE CENTRAL AND NORTHERN
PLAINS. PLENTY OF CLOUD COVER CAN BE EXPECTED THROUGH MOST OF THE
MEMORIAL DAY WEEKEND...WITH AREAS OF OVERCAST LOW STRATUS CLOUDS
AND BROKEN TO OCCASIONALLY OVERCAST MID AND HIGH LEVEL CLOUDS.
HIGH TEMPERATURES THROUGH THE WEEKEND WILL BE A CHALLENGE...AND
COULD END UP BEING COOLER IF THE LOWER STRATUS CLOUD DECK DOES NOT
DISSIPATE. THIS SEEMS MOST LIKELY TO OCCUR BOTH FRIDAY AND
SATURDAY...AND HAVE TRENDED THE HIGHS ON BOTH OF THOSE DAYS DOWN A
COUPLE OF DEGREES. IF IT BECOMES OBVIOUS THE STRATUS WILL NOT
CLEAR OR THIN OUT...THEN HIGHS WILL HAVE TO BE LOWERED FURTHER
INTO THE MID AND UPPER 60S ON THOSE TWO DAYS.
PRECIPITATION CHANCES LOOK OKAY BUT NOT GREAT FRIDAY THROUGH
MEMORIAL DAY. THE 28/00Z RUNS OF THE GFS AND ECMWF KEEP THE BEST
DYNAMICS ACROSS THE SOUTHERN PLAINS...AND WITH NO REAL BOUNDARIES
ACROSS THE REGION FOR CONVECTION TO FOCUS ON...WILL BE
CONSERVATIVE WITH THE POP CHANCES. IN FACT WILL TAPER BACK CHANCES
JUST A BIT FROM THE PREVIOUS FORECAST...AS THE ECMWF HAS TRENDED
TOWARD THE FARTHER SOUTH GFS.
WILL KEEP CONDITIONS DRY TUESDAY AND BEYOND...AS THE UPPER LOW
SHOULD BE EAST/SOUTHEAST OF THE REGION BY THEN. LOW LEVEL
MOISTURE WILL BE LEFT IN IT/S WAKE HOWEVER...AND THE NEXT SYSTEM
WILL HAVE PLEANTY OF MOISTURE TO WORK WITH AS IT APPROACHES LATE
IN THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 132 AM CDT THU MAY 22 2014
FOR THE 06Z KLBF AND KVTN TAFS...THE NEAR TERM CONVECTIVE
ALLOWING MODELS HAVE BACKED OFF ON ADDITIONAL STORMS THURSDAY
MORNING/EARLY AFTERNOON...WHEREAS OUR LATEST NAM12 GUIDANCE
SUGGESTS STORM RE-DEVELOPMENT AS EARLY AS 15Z. ATTM...WILL SIDE
WITH THE NEAR TERM GUIDANCE OF THE RAP13 AND HRRR WHICH HOLDS OFF
STORMS UNTIL AFTER 18Z OR LATER. WITH LOW CONFIDENCE...WILL
INCLUDE A PROB30 AT KLBF FOR 00-04Z...AND KEEP KVTN DRY. UPDATES
MAY BE AND ARE EXPECTED.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ROBERG
LONG TERM...TAYLOR
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
133 AM CDT THU MAY 22 2014
.SYNOPSIS...
ISSUED AT 322 PM CDT WED MAY 21 2014
A FAIRLY STAGNANT UPPER LEVEL PATTERN WAS NOTED ACROSS
THE LOWER 48 THIS MORNING. WITH THE EXCEPTION OF FLAGSTAFF AZ...NO
UA SITES HAD HT FALLS OR RISES IN EXCESS OF 50 METERS. THE MAIN
FEATURES OF NOTE ACROSS THE LOWER 48 WERE HIGH PRESSURE OVER THE
MISSISSIPPI DELTA...A STRONG SHORTWAVE OFF THE COAST OF MAINE...AND
A CLOSED LOW OVER NEVADA. A WEAK JET STREAK AROUND 50 KTS WAS NOTED
FROM NRN AZ INTO WESTERN COLORADO. A COUPLE OF WEAK SHORTWAVES WERE
NOTED EARLY THIS AFTERNOON ALONG THE WESTERN SLOPES OF
COLORADO...AND OVER EASTERN NEW MEXICO. THESE TWO DISTURBANCES HAVE
LED TO INCREASED CLOUD COVER OVER WESTERN COLORADO...WYOMING...AS
WELL AS EASTERN NEW MEXICO AND THE TX PANHANDLE. AT THE
SURFACE...HIGH PRESSURE HAS PUSHED INTO THE DAKOTAS AND NORTHERN
NEBRASKA THIS AFTERNOON...FORCING A FRONTAL BOUNDARY INTO THE TEXAS
PANHANDLE. THIS BOUNDARY THEN WINDS TO THE WEST NORTHWEST ALONG THE
FRONT RANGE OF COLORADO AND WYOMING. WITH EASTERLY AND NORTHEASTERLY
WINDS...UNDER CLEAR TO PARTLY CLOUDY SKIES...2 PM CDT TEMPERATURES
RANGED FROM 65 AT AINSWORTH...TO 75 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 322 PM CDT WED MAY 21 2014
WEAK PV ANOMALY MOVING NWD ALONG THE FRONT RANGE OF CO PER WV
IMAGERY SHOULD CONTINUE TO GENERATE SFC PRESSURE FALLS IN THE LEE OF
THE PALMER DIVIDE AND ENHANCE EXISTING UPSLOPE FLOW TO INITIATE TSRA
ALONG THE HIGHER TERRAIN INITIALLY...WITH ORGANIZED CONVECTIVE
MOVEMENT EXPECTED TO BE NORTHEASTWARD INTO WESTERN AND SW NEB. SHORT
RANGE MODEL FCST SOUNDINGS INDICATE SOME REMAINING...THOUGH
ELEVATED...INSTABILITY OVERNIGHT. HOWEVER MOISTURE IS NOT OVERLY
IMPRESSIVE FURTHER NORTHEAST INTO CENTAL NEBR SINCE NRLY/NERLY FLOW
AT THE SFC ADVECTING ONLY MID TO UPPER 40S DEW POINTS. IN THE
ABSENCE OF A WELL DEFINED LLJ CONVECTION WILL HAVE A DIFFICULT TIME
BEING SUSTAINED INTO CENTRAL NEBR...MUCH LIKE LAST FEW NIGHTS.
HOWEVER...SINCE ORGANIZED CONVECTION WILL LIKELY BE MORE WIDESPREAD
IT MAY HAVE BETTER POTENTIAL. SHORT RANGE MODELS CURRENTLY ARE IN
DISAGREEMENT WITH THIS. HRRR ENSEMBLE UPDRAFT HELICITY SUGGESTS
ORGANIZATION OF INDIVIDUAL UPDRAFTS WOULD WEAKEN AS ANY REMAINING
STORMS MOVE INTO SW NEB. HARD TO ASSESS POTENTIAL FOR SVR...MODELS
SOUNDINGS SHOW SOME CAPE IN THE LOWER RANGE OF THE HAIL GROWTH
REGION...STILL BETTER POPS ARE INCLUDED TONIGHT MOST AREAS THAN PREV
NIGHTS.
WOULD EXPECT A SIMILAR SCENARIO THURSDAY MORNING AS WITH LAST COUPLE
OF MORNINGS IN THAT CONVECTIVE DEBRIS WILL REMAIN ACROSS SOME
PORTIONS OF THE CWA...THOUGH PINPOINTING WHERE IS DIFFICULT.
THEREFORE POPS INCLUDED PRIMARILY WHERE ELEVATED INSTABILITY
RESIDES. UPPER LOW OVER THE SOUTHWEST MOVES LITTLE BUT PIVOTS TO
BECOME SLIGHTLY NEGATIVELY TILTED THURS AFTERNOON. AS A RESULT WINDS
SHOULD BECOME MORE SOUTHEASTERLY AND ADVECT BETTER MOISTURE BACK
INTO THE AREA. FEEL MORE ORGANIZED CONVECTION THURSDAY SHOULD AGAIN
ENTER WESTERN NEB AFTER 00Z FRI. HIGHS WILL BE TEMPERED SOME BY
CLOUD COVER EARLY...BUT SHOULD RECOVER IN THE AFTERNOON MUCH LIKE
TODAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 322 PM CDT WED MAY 21 2014
FOR THURSDAY NIGHT THROUGH SATURDAY...PRECIPITATION CHANCES CONTINUE
TO BE THE MAIN FORECASTING CHALLENGE IN THE MID RANGE PERIODS. LIKE
THIS AFTERNOON...THUNDERSTORMS ARE EXPECTED TO BE ONGOING BY
THURSDAY EVENING OVER NERN COLORADO AND NWRN KS INVOF OF A STALLED
OUT FRONTAL BOUNDARY. WEAK SOUTHERLY AND SSWRLY STEERING WINDS WILL
LIFT THIS ACTIVITY NORTH INTO WESTERN NEBRASKA THURSDAY EVENING. AS
HAS BEEN THE CASE OVER THE PAST COUPLE OF NIGHTS...THIS ACTIVITY HAS
WEAKENED SUBSTANTIALLY AS IT MOVES INTO THE FORECAST AREA FROM THE
WEST AND SOUTHWEST. HOWEVER...TOMORROW NIGHT INTO FRIDAY...LOW LEVEL
WINDS WILL SHIFT MORE TO THE SOUTHEAST AS SURFACE HIGH PRESSURE
LIFTS INTO THE UPPER MISSISSIPPI VALLEY THIS SHIFT IN THE WIND
DIRECTION WILL SERVE TWO PURPOSES...A INCREASE LOW LEVEL
MOISTURE-BRINGING DEW POINTS BACK INTO THE 50S AND B...LEAD TO A 20
TO 30 KT LOW LEVEL JET THURSDAY NIGHT...WHICH WILL HELP TO SUSTAIN
CONVECTION INTO THE LATE NIGHT HOURS. WITH THE FLOW BEING FAIRLY
WEAK IN THE MID LEVELS AND DEEP MID LAYER INSTABILITY BEING FAIRLY
MEAGER...DECIDED TO LEAVE POPS IN THE 30 TO 50 PERCENT RANGE AS
COVERAGE IS EXPECTED TO REMAIN SCATTERED. ON FRIDAY...THE FRONTAL
BOUNDARY WILL LIFT NORTH INTO SOUTHWESTERN AND WESTERN
NEBRASKA...ALLOWING SHOWERS AND THUNDERSTORMS TO LINGER DURING THE
DAYTIME HOURS. CAPPING ON FRIDAY IS WEAK PER THE LATEST NAM AND GFS
SOLNS...SO AFTERNOON HEATING DURING THE DAYTIME HOURS...WILL QUICKLY
LEAD TO ADDITIONAL SHOWER AND THUNDERSTORM DEVELOPMENT. IN
ADDITION...FCST QPF`S ARE EXPECTED TO BE THE HIGHEST FRIDAY/FRIDAY
NIGHT...GIVEN THE EXPECTED WEAK STEERING WINDS AND PWATS OF 1.25 TO
1.50 INCHES. WITH RESPECT TO SEVERE POTENTIAL FRIDAY...AT THIS
TIME...THE SEVERE THREAT FOR FRIDAY APPEARS TO BE MARGINAL GIVEN THE
WEAK MID LEVEL FLOW...ALONG WITH LITTLE OR NO CAP...WHICH WILL
PRODUCE COMPETING UPDRAFTS AND DISORGANIZED CLUSTERS OF STORMS. ON
SATURDAY...THE FRONTAL BOUNDARY WILL LIFT EAST INTO CENTRAL PORTIONS
OF THE FORECAST AREA...FORCED BY THE APPROACH OF THE UPPER LEVEL LOW
AND TROUGH...WHICH WILL REACH THE FOUR CORNERS BY 00Z SUNDAY. THOUGH
PCPN CHANCES REMAIN POSSIBLE ACROSS THE ENTIRE FORECAST AREA...THE
HIGHEST POPS SATURDAY AND SATURDAY NIGHT WILL BE CARRIED ALONG AND
NORTH OF THE FRONT...IMPACTING MAINLY NORTHERN AND EASTERN PORTIONS
OF THE FORECAST AREA.
SUNDAY THROUGH WEDNESDAY...THE UPPER LEVEL LOW WILL BEGIN TO FILL ON
SUNDAY AS IT LIFTS EAST INTO THE SRN PLAINS. PCPN CHANCES WILL
LINGER SUNDAY INTO MONDAY...BEFORE THE SYSTEM EXITS THE SOUTHERN
PLAINS INTO THE ARKLATEX. DRIER AND WARMER CONDITIONS ARE EXPECTED
TUESDAY INTO WEDNESDAY AS A POSITIVELY TILTED RIDGE EXTENDS FROM THE
DESERT SOUTHWEST INTO NRN MINNESOTA. HIGHS WILL RETURN TO THE LOWER
80S FROM THE MIDDLE 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 132 AM CDT THU MAY 22 2014
FOR THE 06Z KLBF AND KVTN TAFS...THE NEAR TERM CONVECTIVE
ALLOWING MODELS HAVE BACKED OFF ON ADDITIONAL STORMS THURSDAY
MORNING/EARLY AFTERNOON...WHEREAS OUR LATEST NAM12 GUIDANCE
SUGGESTS STORM RE-DEVELOPMENT AS EARLY AS 15Z. ATTM...WILL SIDE
WITH THE NEAR TERM GUIDANCE OF THE RAP13 AND HRRR WHICH HOLDS OFF
STORMS UNTIL AFTER 18Z OR LATER. WITH LOW CONFIDENCE...WILL
INCLUDE A PROB30 AT KLBF FOR 00-04Z...AND KEEP KVTN DRY. UPDATES
MAY BE AND ARE EXPECTED.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...JWS
LONG TERM...CLB
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1031 AM PDT THU MAY 22 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CIRCULATE OVER SOUTHERN
NEVADA AND SURROUNDING AREAS THROUGH FRIDAY PRODUCING ISOLATED TO
SCATTERED SHOWERS AND A FEW THUNDERSTORMS. THE SYSTEM WILL
FINALLY MOVE AWAY TO THE EAST SATURDAY...WITH RAIN CHANCES
DIMINISHING AND TEMPERATURES QUICKLY WARMING OVER THE HOLIDAY
WEEKEND.
&&
.UPDATE...QUICK UPDATE TO BUMP UP POPS 10-20 PERCENT OVER CENTRAL
SAN BERNARDINO COUNTY. SHORT RANGE MODELS CONTINUE TO SHOW
INCREASING INSTABILITY OVER THIS AREA AND CONVECTION HAS BEGUN TO
INITIATE OVER THE HIGHER TERRAIN.
&&
.PREV UPDATE...
ISSUED 839 AM PDT THU MAY 22 2014
.PREV UPDATE...A FEW LIGHT SHOWERS ARE ONGOING OVER INYO AND SAN
BERNARDINO COUNTY THIS MORNING. MADE SOME TWEAKS TO THE
SKY/POP/QPF/WX GRIDS THROUGH THIS EVENING BASED OFF THE LATEST
RADAR/SATELLITE IMAGERY AND HIGH-RES MODEL GUIDANCE. I EXPANDED
POPS A BIT FURTHER EAST IN SAN BERNARDINO COUNTY...AND REDUCED THEM
OVER CENTRAL NYE. IN GENERAL THERE IS AT LEAST A SLIGHT CHANCE OF
SHOWERS AND ISOLATED THUNDERSTORMS EAST OF US 95 TODAY...WITH THE
BEST CHANCES OVER THE TERRAIN OF INYO AND SAN BERNARDINO COUNTIES.
WITH LIMITED MOISTURE TO WORK WITH GUSTY WINDS TO 30-40 MPH WILL BE
THE PRIMARY THREAT WITH ANY STORMS TODAY. THERE WILL BE THE
POTENTIAL FOR SOME GUSTS TO AROUND 50 MPH IN SAN BERNARDINO COUNTY.
GENERAL STORM MOTION WILL BE WEST AT 5-10 MPH.
&&
.PREV UPDATE...
ISSUED 632 AM PDT THU MAY 22 2014
.PREV UPDATE...NEEDED TO INCREASE POPS AND CLOUDS ACROSS WESTERN
INYO COUNTY FOR THE REST OF THIS MORNING. NEW TEXT PRODUCTS SENT ON
THE HALF HOUR. NO OTHER CHANGES.
.PREV DISCUSSION...
300 AM PDT THU MAY 22 2014
.SHORT TERM...THROUGH SATURDAY NIGHT...WATER VAPOR SHOWS TWO
DISTINCT WAVES CIRCULATING WITHIN THE TROUGH WHICH HAS CUTOFF FROM
THE WESTERLIES OVER NEVADA/CALIFORNIA. FIRST SHORTWAVE OVER WEST
CENTRAL NEVADA WILL BE MOVING SOUTHWEST THROUGH MONO/NORTHWEST INYO
COUNTIES THIS MORNING. THE LATEST HRRR SPREADS LIGHT SHOWERS SOUTH
THROUGH THE EASTERN SIERRA SLOPES OF INYO AS WELL AS THE NORTHERN
OWEN VALLEY THROUGH 8 OR 9 AM THIS MORNING. SECOND WAVE WAS ALONG
THE SOUTHERN CALIFORNIA COAST HELPING DEEPEN THE MARINE LAYER.
TODAY, MODELS REMAIN IN GOOD AGREEMENT INDICATING MOISTURE AND
INSTABILITY WILL STAY IN THE WESTERN HALF OF THE FORECAST AREA OR
WEST OF LAS VEGAS. AS TROUGH/UPPER LOW SLOWLY SHIFTS FROM SOUTHERN
CALIFORNIA EAST INTO ARIZONA THE PROBABILITIES FOR SHOWERS WILL
FINALLY INCREASE FOR THE HIGHER TERRAIN OF MOHAVE/LINCOLN AND
EASTERN CLARK COUNTIES FRIDAY AND SATURDAY. TO KICK OFF THE HOLIDAY
WEEKEND ON FRIDAY AND SATURDAY TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE NORMAL. ONLY WIND CONCERN OVER THE COMING DAYS WILL BE FROM
THUNDERSTORMS WHERE GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
.LONG TERM...SUNDAY THROUGH THURSDAY NIGHT.
THE MAIN TREND IN THE UPCOMING WEEK APPEARS TO BE A COOLING TREND,
THOUGH HOW BIG OF A COOLING TREND REMAINS UP FOR DEBATE. A
POSITIVELY TILTED MID/UPPER LEVEL RIDGE IS SHOWN TO EXTEND INTO
CALIFORNIA AND NEVADA ON SUNDAY INTO MEMORIAL DAY AHEAD OF AN
INCOMING MID/UPPER LEVEL TROUGH THAT DIGS SOUTH ACROSS THE PAC NW
INTO NORCAL. THE 00Z OPERATIONAL GFS AND TO A LESSER EXTENT THE
SLIGHTLY DRIER ECMWF BOTH SHOW ENOUGH INSTABILITY, CAPE AND
MID-LEVEL MOISTURE ON SUNDAY AFTERNOON OVER THE SOUTHERN SIERRA AND
WHITE MOUNTAINS THAT WE SHOULD SEE AT LEAST SOME CUMULUS BUILD-UPS.
HOWEVER, A FEW SHOWERS OR EVEN A THUNDERSTORM MAY MATERIALIZE AND
POPS WERE INCREASED TO THE 10-15 PERCENT RANGE OVER THESE AREAS FOR
SUNDAY AFTERNOON AND EVENING. BY MONDAY, THINGS LOOK MORE STABLE AS
THE TROUGH APPROACHES, AT THUS THE FORECAST GRIDS ONLY REFLECT
DEVELOPMENT OF CUMULUS IN THE AFTERNOON OVER THESE AREAS. AHEAD OF
THE INCOMING TROUGH, INCREASING SOUTHWEST FLOW WILL ALLOW FOR GOOD
MIXING AND THUS HIGH TEMPS WERE BOOSTED A COUPLE OF DEGREES OVER THE
PREVIOUS FORECAST, ESPECIALLY FOR MEMORIAL DAY BASED ON FORECAST
SOUNDINGS AND STATISTICAL GUIDANCE.
AS WE MOVE INTO THE MIDDLE OF NEXT WEEK, THE TROUGH ALOFT IS
FORECAST TO REMAIN INTO NORCAL WITH A SOUTHWEST FLOW SETTING UP
ACROSS OUR ENTIRE AREA. AS HEIGHTS SLOWLY LOWER AND TEMPS ALOFT
COOL, TEMPS AT THE SURFACE WILL ALSO GRADUALLY DROP A FEW DEGREES
EACH DAY FROM TUESDAY ONWARD, HOWEVER, THEY SHOULD STILL REMAIN AT
LEAST A FEW DEGREES ABOVE NORMAL. THE MOST NOTICEABLE DROP SHOULD BE
IN THE WESTERN CWFA WHERE IT IS POSSIBLE THE SYNOPTIC COOLING ALSO
GETS A LITTLE BOOST FROM ANY MARINE INFLUENCE THAT CAN TRICKLE
THROUGH THE COASTAL RANGE PASSES. OTHERWISE EXPECT DRY CONDITIONS
WITH A FEW CLOUDS AROUND AT TIMES.
&&
.AVIATION...FOR MCCARRAN...WIND SPEEDS UNDER 8 KTS THIS MORNING
WITH AN EASTERLY WIND COMPONENT DEVELOPING THIS AFTERNOON. CLOUDS
DEVELOPING THROUGHOUT THE DAY WITH BASES 10-12 KFT WITH LIGHT
SHOWERS POSSIBLE OVER THE SPRING MOUNTAINS AND SHEEP RANGE THIS
AFTERNOON AND EVENING.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...A LOW PRESSURE
SYSTEM WILL BE OVER SOUTHERN CALIFORNIA TODAY. ISOLATED TO SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED IN AREAS TO THE
WEST OF LAS VEGAS. CLOUD BASES WILL GENERALLY BE AROUND 8-10
KFT MSL AND WILL LEAD TO PARTIAL MOUNTAIN OBSCURATION OVER THE
SOUTHERN SIERRA.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
UPDATE...WOLCOTT
PREV DISCUSSION...PIERCE/STACHELSKI
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
839 AM PDT THU MAY 22 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CIRCULATE OVER SOUTHERN
NEVADA AND SURROUNDING AREAS THROUGH FRIDAY PRODUCING ISOLATED TO
SCATTERED SHOWERS AND A FEW THUNDERSTORMS. THE SYSTEM WILL
FINALLY MOVE AWAY TO THE EAST SATURDAY...WITH RAIN CHANCES
DIMINISHING AND TEMPERATURES QUICKLY WARMING OVER THE HOLIDAY
WEEKEND.
&&
.UPDATE...A FEW LIGHT SHOWERS ARE ONGOING OVER INYO AND SAN
BERNARDINO COUNTY THIS MORNING. MADE SOME TWEAKS TO THE
SKY/POP/QPF/WX GRIDS THROUGH THIS EVENING BASED OFF THE LATEST
RADAR/SATELLITE IMAGERY AND HIGH-RES MODEL GUIDANCE. I EXPANDED
POPS A BIT FURTHER EAST IN SAN BERNARDINO COUNTY...AND REDUCED THEM
OVER CENTRAL NYE. IN GENERAL THERE IS AT LEAST A SLIGHT CHANCE OF
SHOWERS AND ISOLATED THUNDERSTORMS EAST OF US 95 TODAY...WITH THE
BEST CHANCES OVER THE TERRAIN OF INYO AND SAN BERNARDINO COUNTIES.
WITH LIMITED MOISTURE TO WORK WITH GUSTY WINDS TO 30-40 MPH WILL BE
THE PRIMARY THREAT WITH ANY STORMS TODAY. THERE WILL BE THE
POTENTIAL FOR SOME GUSTS TO AROUND 50 MPH IN SAN BERNARDINO COUNTY.
GENERAL STORM MOTION WILL BE WEST AT 5-10 MPH.
&&
.PREV UPDATE...
ISSUED 632 AM PDT THU MAY 22 2014
.UPDATE...NEEDED TO INCREASE POPS AND CLOUDS ACROSS WESTERN INYO
COUNTY FOR THE REST OF THIS MORNING. NEW TEXT PRODUCTS SENT ON THE
HALF HOUR. NO OTHER CHANGES.
.PREV DISCUSSION...
300 AM PDT THU MAY 22 2014
.SHORT TERM...THROUGH SATURDAY NIGHT...WATER VAPOR SHOWS TWO
DISTINCT WAVES CIRCULATING WITHIN THE TROUGH WHICH HAS CUTOFF FROM
THE WESTERLIES OVER NEVADA/CALIFORNIA. FIRST SHORTWAVE OVER WEST
CENTRAL NEVADA WILL BE MOVING SOUTHWEST THROUGH MONO/NORTHWEST INYO
COUNTIES THIS MORNING. THE LATEST HRRR SPREADS LIGHT SHOWERS SOUTH
THROUGH THE EASTERN SIERRA SLOPES OF INYO AS WELL AS THE NORTHERN
OWEN VALLEY THROUGH 8 OR 9 AM THIS MORNING. SECOND WAVE WAS ALONG
THE SOUTHERN CALIFORNIA COAST HELPING DEEPEN THE MARINE LAYER.
TODAY, MODELS REMAIN IN GOOD AGREEMENT INDICATING MOISTURE AND
INSTABILITY WILL STAY IN THE WESTERN HALF OF THE FORECAST AREA OR
WEST OF LAS VEGAS. AS TROUGH/UPPER LOW SLOWLY SHIFTS FROM SOUTHERN
CALIFORNIA EAST INTO ARIZONA THE PROBABILITIES FOR SHOWERS WILL
FINALLY INCREASE FOR THE HIGHER TERRAIN OF MOHAVE/LINCOLN AND
EASTERN CLARK COUNTIES FRIDAY AND SATURDAY. TO KICK OFF THE HOLIDAY
WEEKEND ON FRIDAY AND SATURDAY TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE NORMAL. ONLY WIND CONCERN OVER THE COMING DAYS WILL BE FROM
THUNDERSTORMS WHERE GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
.LONG TERM...SUNDAY THROUGH THURSDAY NIGHT.
THE MAIN TREND IN THE UPCOMING WEEK APPEARS TO BE A COOLING TREND,
THOUGH HOW BIG OF A COOLING TREND REMAINS UP FOR DEBATE. A
POSITIVELY TILTED MID/UPPER LEVEL RIDGE IS SHOWN TO EXTEND INTO
CALIFORNIA AND NEVADA ON SUNDAY INTO MEMORIAL DAY AHEAD OF AN
INCOMING MID/UPPER LEVEL TROUGH THAT DIGS SOUTH ACROSS THE PAC NW
INTO NORCAL. THE 00Z OPERATIONAL GFS AND TO A LESSER EXTENT THE
SLIGHTLY DRIER ECMWF BOTH SHOW ENOUGH INSTABILITY, CAPE AND
MID-LEVEL MOISTURE ON SUNDAY AFTERNOON OVER THE SOUTHERN SIERRA AND
WHITE MOUNTAINS THAT WE SHOULD SEE AT LEAST SOME CUMULUS BUILD-UPS.
HOWEVER, A FEW SHOWERS OR EVEN A THUNDERSTORM MAY MATERIALIZE AND
POPS WERE INCREASED TO THE 10-15 PERCENT RANGE OVER THESE AREAS FOR
SUNDAY AFTERNOON AND EVENING. BY MONDAY, THINGS LOOK MORE STABLE AS
THE TROUGH APPROACHES, AT THUS THE FORECAST GRIDS ONLY REFLECT
DEVELOPMENT OF CUMULUS IN THE AFTERNOON OVER THESE AREAS. AHEAD OF
THE INCOMING TROUGH, INCREASING SOUTHWEST FLOW WILL ALLOW FOR GOOD
MIXING AND THUS HIGH TEMPS WERE BOOSTED A COUPLE OF DEGREES OVER THE
PREVIOUS FORECAST, ESPECIALLY FOR MEMORIAL DAY BASED ON FORECAST
SOUNDINGS AND STATISTICAL GUIDANCE.
AS WE MOVE INTO THE MIDDLE OF NEXT WEEK, THE TROUGH ALOFT IS
FORECAST TO REMAIN INTO NORCAL WITH A SOUTHWEST FLOW SETTING UP
ACROSS OUR ENTIRE AREA. AS HEIGHTS SLOWLY LOWER AND TEMPS ALOFT
COOL, TEMPS AT THE SURFACE WILL ALSO GRADUALLY DROP A FEW DEGREES
EACH DAY FROM TUESDAY ONWARD, HOWEVER, THEY SHOULD STILL REMAIN AT
LEAST A FEW DEGREES ABOVE NORMAL. THE MOST NOTICEABLE DROP SHOULD BE
IN THE WESTERN CWFA WHERE IT IS POSSIBLE THE SYNOPTIC COOLING ALSO
GETS A LITTLE BOOST FROM ANY MARINE INFLUENCE THAT CAN TRICKLE
THROUGH THE COASTAL RANGE PASSES. OTHERWISE EXPECT DRY CONDITIONS
WITH A FEW CLOUDS AROUND AT TIMES.
&&
.AVIATION...FOR MCCARRAN...WIND SPEEDS UNDER 8 KTS THIS MORNING
WITH AN EASTERLY WIND COMPONENT DEVELOPING THIS AFTERNOON. CLOUDS
DEVELOPING THROUGHOUT THE DAY WITH BASES 10-12 KFT WITH LIGHT
SHOWERS POSSIBLE OVER THE SPRING MOUNTAINS AND SHEEP RANGE THIS
AFTERNOON AND EVENING.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...A LOW PRESSURE
SYSTEM WILL BE OVER SOUTHERN CALIFORNIA TODAY. ISOLATED TO SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED IN AREAS TO THE
WEST OF LAS VEGAS. CLOUD BASES WILL GENERALLY BE AROUND 8-10
KFT MSL AND WILL LEAD TO PARTIAL MOUNTAIN OBSCURATION OVER THE
SOUTHERN SIERRA.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
UPDATE...WOLCOTT
PREV DISCUSSION...PIERCE/STACHELSKI
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
632 AM PDT THU MAY 22 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CIRCULATE OVER SOUTHERN
NEVADA AND SURROUNDING AREAS THROUGH FRIDAY PRODUCING ISOLATED TO
SCATTERED SHOWERS AND A FEW THUNDERSTORMS. THE SYSTEM WILL
FINALLY MOVE AWAY TO THE EAST SATURDAY...WITH RAIN CHANCES
DIMINISHING AND TEMPERATURES QUICKLY WARMING OVER THE HOLIDAY
WEEKEND.
&&
.UPDATE...NEEDED TO INCREASE POPS AND CLOUDS ACROSS WESTERN INYO
COUNTY FOR THE REST OF THIS MORNING. NEW TEXT PRODUCTS SENT ON THE
HALF HOUR. NO OTHER CHANGES.
.PREV DISCUSSION...
300 AM PDT THU MAY 22 2014
.SHORT TERM...THROUGH SATURDAY NIGHT...WATER VAPOR SHOWS TWO
DISTINCT WAVES CIRCULATING WITHIN THE TROUGH WHICH HAS CUTOFF FROM
THE WESTERLIES OVER NEVADA/CALIFORNIA. FIRST SHORTWAVE OVER WEST
CENTRAL NEVADA WILL BE MOVING SOUTHWEST THROUGH MONO/NORTHWEST INYO
COUNTIES THIS MORNING. THE LATEST HRRR SPREADS LIGHT SHOWERS SOUTH
THROUGH THE EASTERN SIERRA SLOPES OF INYO AS WELL AS THE NORTHERN
OWEN VALLEY THROUGH 8 OR 9 AM THIS MORNING. SECOND WAVE WAS ALONG
THE SOUTHERN CALIFORNIA COAST HELPING DEEPEN THE MARINE LAYER.
TODAY, MODELS REMAIN IN GOOD AGREEMENT INDICATING MOISTURE AND
INSTABILITY WILL STAY IN THE WESTERN HALF OF THE FORECAST AREA OR
WEST OF LAS VEGAS. AS TROUGH/UPPER LOW SLOWLY SHIFTS FROM SOUTHERN
CALIFORNIA EAST INTO ARIZONA THE PROBABILITIES FOR SHOWERS WILL
FINALLY INCREASE FOR THE HIGHER TERRAIN OF MOHAVE/LINCOLN AND
EASTERN CLARK COUNTIES FRIDAY AND SATURDAY. TO KICK OFF THE HOLIDAY
WEEKEND ON FRIDAY AND SATURDAY TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE NORMAL. ONLY WIND CONCERN OVER THE COMING DAYS WILL BE FROM
THUNDERSTORMS WHERE GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
.LONG TERM...SUNDAY THROUGH THURSDAY NIGHT.
THE MAIN TREND IN THE UPCOMING WEEK APPEARS TO BE A COOLING TREND,
THOUGH HOW BIG OF A COOLING TREND REMAINS UP FOR DEBATE. A
POSITIVELY TILTED MID/UPPER LEVEL RIDGE IS SHOWN TO EXTEND INTO
CALIFORNIA AND NEVADA ON SUNDAY INTO MEMORIAL DAY AHEAD OF AN
INCOMING MID/UPPER LEVEL TROUGH THAT DIGS SOUTH ACROSS THE PAC NW
INTO NORCAL. THE 00Z OPERATIONAL GFS AND TO A LESSER EXTENT THE
SLIGHTLY DRIER ECMWF BOTH SHOW ENOUGH INSTABILITY, CAPE AND
MID-LEVEL MOISTURE ON SUNDAY AFTERNOON OVER THE SOUTHERN SIERRA AND
WHITE MOUNTAINS THAT WE SHOULD SEE AT LEAST SOME CUMULUS BUILD-UPS.
HOWEVER, A FEW SHOWERS OR EVEN A THUNDERSTORM MAY MATERIALIZE AND
POPS WERE INCREASED TO THE 10-15 PERCENT RANGE OVER THESE AREAS FOR
SUNDAY AFTERNOON AND EVENING. BY MONDAY, THINGS LOOK MORE STABLE AS
THE TROUGH APPROACHES, AT THUS THE FORECAST GRIDS ONLY REFLECT
DEVELOPMENT OF CUMULUS IN THE AFTERNOON OVER THESE AREAS. AHEAD OF
THE INCOMING TROUGH, INCREASING SOUTHWEST FLOW WILL ALLOW FOR GOOD
MIXING AND THUS HIGH TEMPS WERE BOOSTED A COUPLE OF DEGREES OVER THE
PREVIOUS FORECAST, ESPECIALLY FOR MEMORIAL DAY BASED ON FORECAST
SOUNDINGS AND STATISTICAL GUIDANCE.
AS WE MOVE INTO THE MIDDLE OF NEXT WEEK, THE TROUGH ALOFT IS
FORECAST TO REMAIN INTO NORCAL WITH A SOUTHWEST FLOW SETTING UP
ACROSS OUR ENTIRE AREA. AS HEIGHTS SLOWLY LOWER AND TEMPS ALOFT
COOL, TEMPS AT THE SURFACE WILL ALSO GRADUALLY DROP A FEW DEGREES
EACH DAY FROM TUESDAY ONWARD, HOWEVER, THEY SHOULD STILL REMAIN AT
LEAST A FEW DEGREES ABOVE NORMAL. THE MOST NOTICEABLE DROP SHOULD BE
IN THE WESTERN CWFA WHERE IT IS POSSIBLE THE SYNOPTIC COOLING ALSO
GETS A LITTLE BOOST FROM ANY MARINE INFLUENCE THAT CAN TRICKLE
THROUGH THE COASTAL RANGE PASSES. OTHERWISE EXPECT DRY CONDITIONS
WITH A FEW CLOUDS AROUND AT TIMES.
&&
.AVIATION...FOR MCCARRAN...WIND SPEEDS UNDER 8 KTS THIS MORNING WITH
AN EASTERLY WIND COMPONENT DEVELOPING THIS AFTERNOON. CLOUDS
DEVELOPING THROUGHOUT THE DAY WITH BASES 10-12 KFT WITH LIGHT
SHOWERS POSSIBLE OVER THE SPRING MOUNTAINS AND SHEEP RANGE
THIS AFTERNOON AND EVENING.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...A LOW PRESSURE
SYSTEM WILL BE OVER SOUTHERN CALIFORNIA TODAY. ISOLATED TO SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED IN AREAS TO THE
WEST OF LAS VEGAS. CLOUD BASES WILL GENERALLY BE AROUND 8-10
KFT MSL AND WILL LEAD TO PARTIAL MOUNTAIN OBSCURATION OVER THE
SOUTHERN SIERRA.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
PIERCE/STACHELSKI
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
300 AM PDT THU MAY 22 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CIRCULATE OVER SOUTHERN
NEVADA AND SURROUNDING AREAS THROUGH FRIDAY PRODUCING ISOLATED TO
SCATTERED SHOWERS AND A FEW THUNDERSTORMS. THE SYSTEM WILL
FINALLY MOVE AWAY TO THE EAST SATURDAY...WITH RAIN CHANCES
DIMINISHING AND TEMPERATURES QUICKLY WARMING OVER THE HOLIDAY
WEEKEND.
&&
.SHORT TERM...THROUGH SATURDAY NIGHT...WATER VAPOR SHOWS TWO
DISTINCT WAVES CIRCULATING WITHIN THE TROUGH WHICH HAS CUTOFF FROM
THE WESTERLIES OVER NEVADA/CALIFORNIA. FIRST SHORTWAVE OVER WEST
CENTRAL NEVADA WILL BE MOVING SOUTHWEST THROUGH MONO/NORTHWEST INYO
COUNTIES THIS MORNING. THE LATEST HRRR SPREADS LIGHT SHOWERS SOUTH
THROUGH THE EASTERN SIERRA SLOPES OF INYO AS WELL AS THE NORTHERN
OWEN VALLEY THROUGH 8 OR 9 AM THIS MORNING. SECOND WAVE WAS ALONG
THE SOUTHERN CALIFORNIA COAST HELPING DEEPEN THE MARINE LAYER.
TODAY, MODELS REMAIN IN GOOD AGREEMENT INDICATING MOISTURE AND
INSTABILITY WILL STAY IN THE WESTERN HALF OF THE FORECAST AREA OR
WEST OF LAS VEGAS. AS TROUGH/UPPER LOW SLOWLY SHIFTS FROM SOUTHERN
CALIFORNIA EAST INTO ARIZONA THE PROBABILITIES FOR SHOWERS WILL
FINALLY INCREASE FOR THE HIGHER TERRAIN OF MOHAVE/LINCOLN AND
EASTERN CLARK COUNTIES FRIDAY AND SATURDAY. TO KICK OFF THE HOLIDAY
WEEKEND ON FRIDAY AND SATURDAY TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE NORMAL. ONLY WIND CONCERN OVER THE COMING DAYS WILL BE FROM
THUNDERSTORMS WHERE GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
.LONG TERM...SUNDAY THROUGH THURSDAY NIGHT.
THE MAIN TREND IN THE UPCOMING WEEK APPEARS TO BE A COOLING TREND,
THOUGH HOW BIG OF A COOLING TREND REMAINS UP FOR DEBATE. A
POSITIVELY TILTED MID/UPPER LEVEL RIDGE IS SHOWN TO EXTEND INTO
CALIFORNIA AND NEVADA ON SUNDAY INTO MEMORIAL DAY AHEAD OF AN
INCOMING MID/UPPER LEVEL TROUGH THAT DIGS SOUTH ACROSS THE PAC NW
INTO NORCAL. THE 00Z OPERATIONAL GFS AND TO A LESSER EXTENT THE
SLIGHTLY DRIER ECMWF BOTH SHOW ENOUGH INSTABILITY, CAPE AND
MID-LEVEL MOISTURE ON SUNDAY AFTERNOON OVER THE SOUTHERN SIERRA AND
WHITE MOUNTAINS THAT WE SHOULD SEE AT LEAST SOME CUMULUS BUILD-UPS.
HOWEVER, A FEW SHOWERS OR EVEN A THUNDERSTORM MAY MATERIALIZE AND
POPS WERE INCREASED TO THE 10-15 PERCENT RANGE OVER THESE AREAS FOR
SUNDAY AFTERNOON AND EVENING. BY MONDAY, THINGS LOOK MORE STABLE AS
THE TROUGH APPROACHES, AT THUS THE FORECAST GRIDS ONLY REFLECT
DEVELOPMENT OF CUMULUS IN THE AFTERNOON OVER THESE AREAS. AHEAD OF
THE INCOMING TROUGH, INCREASING SOUTHWEST FLOW WILL ALLOW FOR GOOD
MIXING AND THUS HIGH TEMPS WERE BOOSTED A COUPLE OF DEGREES OVER THE
PREVIOUS FORECAST, ESPECIALLY FOR MEMORIAL DAY BASED ON FORECAST
SOUNDINGS AND STATISTICAL GUIDANCE.
AS WE MOVE INTO THE MIDDLE OF NEXT WEEK, THE TROUGH ALOFT IS
FORECAST TO REMAIN INTO NORCAL WITH A SOUTHWEST FLOW SETTING UP
ACROSS OUR ENTIRE AREA. AS HEIGHTS SLOWLY LOWER AND TEMPS ALOFT
COOL, TEMPS AT THE SURFACE WILL ALSO GRADUALLY DROP A FEW DEGREES
EACH DAY FROM TUESDAY ONWARD, HOWEVER, THEY SHOULD STILL REMAIN AT
LEAST A FEW DEGREES ABOVE NORMAL. THE MOST NOTICEABLE DROP SHOULD BE
IN THE WESTERN CWFA WHERE IT IS POSSIBLE THE SYNOPTIC COOLING ALSO
GETS A LITTLE BOOST FROM ANY MARINE INFLUENCE THAT CAN TRICKLE
THROUGH THE COASTAL RANGE PASSES. OTHERWISE EXPECT DRY CONDITIONS
WITH A FEW CLOUDS AROUND AT TIMES.
&&
.AVIATION...FOR MCCARRAN...WIND SPEEDS UNDER 8 KTS THIS MORNING WITH
AN EASTERLY WIND COMPONENT DEVELOPING THIS AFTERNOON. CLOUDS
DEVELOPING THROUGHOUT THE DAY WITH BASES 10-12 KFT WITH LIGHT
SHOWERS POSSIBLE OVER THE SPRING MOUNTAINS AND SHEEP RANGE
THIS AFTERNOON AND EVENING.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...A LOW PRESSURE
SYSTEM WILL BE OVER SOUTHERN CALIFORNIA TODAY. ISOLATED TO SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED IN AREAS TO THE
WEST OF LAS VEGAS. CLOUD BASES WILL GENERALLY BE AROUND 8-10
KFT MSL AND WILL LEAD TO PARTIAL MOUNTAIN OBSCURATION OVER THE
SOUTHERN SIERRA.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
PIERCE/STACHELSKI
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
414 AM EDT THU MAY 22 2014
.SYNOPSIS...
AFTER A PLEASANTLY WARM AND DRY WEDNESDAY...AN UPPER-LEVEL
DISTURBANCE OVER THE NORTHERN GREAT LAKES WILL HAVE AN INCREASING
INFLUENCE ON OUR WEATHER AS IT SHIFTS SOUTHEASTWARD ACROSS NEW
YORK AND NEW ENGLAND THURSDAY AND FRIDAY. CLOUDS WILL BE ON THE
INCREASE OVERNIGHT TONIGHT...WITH A CHANCE FOR RAIN SHOWERS
TOWARD MORNING...MAINLY ACROSS NORTHERN NEW YORK AND INTO SOUTH-
CENTRAL VERMONT. SHOWERS WILL BECOME MORE WIDESPREAD ACROSS THE
REGION WITH DAYTIME HEATING ON THURSDAY. LOOK FOR MOSTLY CLOUDY
SKIES WITH NUMEROUS SLOW-MOVING SHOWERS...AND A SLIGHT CHANCE OF
AN AFTERNOON THUNDERSTORM. INTERVALS OF RAIN WILL CONTINUE
THURSDAY NIGHT INTO FRIDAY...WITH THE FOCUS FOR THE MOST
WIDESPREAD ACTIVITY EXPECTED ACROSS NORTHERN NEW YORK. DRIER
WEATHER WILL RETURN FOR THE WEEKEND AS THE UPPER LEVEL LOW SHIFTS
SOUTHEAST OF NEW ENGLAND AND A WEAK RIDGE OF HIGH PRESSURE BUILDS
IN ACROSS THE ST. LAWRENCE VALLEY.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 128 AM EDT THURSDAY...MAIN CHANGE FOR THIS LATEST UPDATE IS
TO RAISE MIN TEMPS AS WE ARE STILL 62 DEGREES HERE AT BTV. USED
THE MATCH LAV WHICH LOOKED GOOD. ALSO RAISED POPS A BIT WHERE
THERE ARE ALREADY SHOWERS ACROSS PARTS OF THE DACKS AND NORTHERN
NY. HAVE ADDED MENTION OF SLIGHT CHANCE THUNDER AS WELL WITH
THUNDERSTORM CURRENTLY MOVING INTO EXTREME WESTERN SAINT LAWRENCE
COUNTRY. PREVIOUS DISCUSSIONS FOLLOW.
ADDL SMALL ADJUSTMENTS TO POPS ACROSS THE AREA
OVERNIGHT...CONFINING ANY ISOLD/WIDELY SCT ACTIVITY TO OUR
SOUTHWESTERN COUNTIES AND LEAVING REMAINDER OF FORECAST AREA
GENERALLY DRY OVERNIGHT. CAN`T COMPLETELY RULE OUT ISOLD THUNDER
SOUTHWEST PER LATEST RAP SHOWALTER PROGS...BUT OMITTED MENTION
DUE TO EXPECTED PAUCITY OF COVERAGE. TEMPS/TD/SKY/WINDS REMAIN ON
TRACK SO NO OTHER CHANGES NEEDED AT THIS POINT. HAVE A GREAT
NIGHT. PRIOR DISCUSSIONS FOLLOW...
PRIOR DISCUSSION... A FEW UPDATES AS WE PROGRESS INTO THE EVENING
HOURS...MAINLY TO INTRODUCE A LOW CHANCE OF SHOWERS FOR THE
WESTERN SLOPES OF THE DACKS INTO THE SLV AND TO INCREASE CLOUD
COVER ACROSS THE AREA SOMEWHAT. CURRENT RADAR SHOWING ISOLD TO
WIDELY SCT SHOWERS HAVE DEVELOPED ACROSS PORTIONS OF THE SLV
EARLY THIS EVENING. SOME HEAVIER T-STORM ACTIVITY ALSO EVIDENT
FURTHER WEST ACROSS SOUTHERN ONTARIO INVOF PEMBROKE/RENFREW WHERE
LOCAL WARNINGS ARE IN EFFECT FROM ENV CANADA. NOT EXPECTING ANY
STORM ACTIVITY TO REACH OUR NRN NY COUNTIES THIS EVENING AS
AIRMASS REMAINS QUITE STABLE OVER OUR AREA. HOWEVER...A MID LEVEL
SHEAR ZONE HAS MATERIALIZED ACROSS THESE AREAS PER LATEST RAP
PROGS...AND WITH AT LEAST SOME SUPPORT FROM ~90KT UPPER LEVEL JET
TO THE IMMEDIATE SOUTHWEST...I LIKE THE MOST RECENT RAP/HRRR
PROGS SHOWING CONTINUED SCT SHOWER ACTIVITY IN THESE AREAS
OVERNIGHT AS MID LEVEL HEIGHTS SLOWLY FALL. MORE LIMITED ACTIVITY
NORTH AND EAST OF A KMSS-KBTV-KVSF LINE UNTIL LATER TONIGHT AS
THESE AREAS INITIALLY FURTHER REMOVED FROM BETTER MOISTURE/UPPER
LEVEL SUPPORT. DID OPT TO BLEND POPS FROM 06Z ONWARD INTO CURRENT
FORECAST AT 12Z...BUT IF CURRENT TRENDS CONTINUE MAY HAVE TO
ADJUST POPS FURTHER DOWNWARD NORTH AND EAST LATER TONIGHT. REST
OF FORECAST IN GOOD SHAPE AT THIS POINT.
PRIOR DISCUSSION... NARROW SFC RIDGE CENTERED ACROSS THE NORTH
COUNTRY RESULTING IN A PLEASANT AFTN WITH JUST SCATTERED FAIR
WEATHER CUMULUS CLOUDS DOTTING THE HIGHER TERRAIN PER AFTN
VISIBLE IMAGERY. 2-M TEMPS REACHED THE MID 70S (77F AT KBTV AT
1830Z) AS EXPECTED AREAWIDE...WITH DELIGHTFULLY LOW DEWPOINTS IN
THE 30S TO LOWER 40S. WINDS HAVE ALSO BEEN RATHER LIGHT IN VCNTY
OF PREVAILING SFC ANTICYCLONE. PLEASANT CONDITIONS WILL CONTINUE
THROUGH THIS EVENING WITH TEMPERATURES FALLING THROUGH THE 60S
WITH ONSET OF DIURNAL COOLING CYCLE.
SOME GRADUAL CHANGES WILL OCCUR LATE TONIGHT. THE 850MB FRONTAL
ZONE ACROSS SRN MI/NRN OH/PA...WHICH HAS BEEN THE FOCUS FOR
SHOWER AND TSTM ACTIVITY OVER THE PAST 12-24 HRS...WILL SLOWLY
LIFT NEWD...BUT IS ALSO EXPECTED TO SLOWLY WEAKEN. AT THE SAME
TIME ...MID-LEVEL HEIGHT FALLS ARE EXPECTED ACROSS NY/VT AS
CLOSED UPR LOW OVER THE NRN GREAT LAKES BEGINS TO SHIFT INTO SERN
ONTARIO OVERNIGHT. IT SHOULD REMAIN DRY THRU MIDNIGHT ALL
SECTIONS...BUT RESULT OF THE FRONTAL ZONE AND HEIGHT FALLS
SUGGESTS WE SHOULD BEGIN TO SEE SOME ISOLD/SCT SHOWER ACTIVITY
DEVELOP ACROSS OUR NRN NY COUNTIES SEWD INTO RUTLAND COUNTY AFTER
MIDNIGHT...AND ESPECIALLY AFTER 09Z. AIR MASS WILL REMAIN QUITE
DRY FURTHER NORTH AND EAST...SO ACTIVITY SHOULD REMAIN SOUTH AND
WEST OF THE CHAMPLAIN VALLEY THRU DAYBREAK BASED ON CURRENT
INDICATIONS. LOOK FOR A GRADUALLY INCREASE IN MID AND UPPER
LEVELS CLOUDS FROM THE CHAMPLAIN VALLEY NORTH AND EASTWARD LATE.
STAYED CLOSE TO MOS CONSENSUS FOR OVERNIGHT LOWS. WITH INCREASE
IN CLOUDS LATE...WILL SEE TEMPS A BIT WARMER THAN THE PREVIOUS
COUPLE OF NIGHTS. LOWS GENERALLY IN THE UPR 40S TO LOWER
50S...EXCEPT MID 40S FOR THE NORMALLY COOLER VALLEYS WITHIN THE
NRN ADIRONDACK REGION AND ACROSS FAR NERN VT. A LIGHT S-SE WIND
WILL DEVELOP OVERNIGHT AS SFC RIDGE SLIDES EWD INTO MAINE.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SATURDAY/...
AS OF 253 PM EDT WEDNESDAY...UNSETTLED WX CONDITIONS EXPECTED
THRU MUCH OF THE PERIOD. LOW-MID LEVEL LOW PRESSURE SYSTEM
ROTATES SEWD FROM SERN ONTARIO INTO THE ST. LAWRENCE VALLEY LATE
THURSDAY AFTN...AND THEN SLIDES SLOWLY SEWD ACROSS CENTRAL NEW
YORK STATE (JUST SOUTH OF THE ADIRONDACKS) AND SRN NEW ENGLAND
THURSDAY NIGHT THROUGH FRIDAY. MODELS CONTINUE TO INDICATE BEST
FOCUS FOR WIDESPREAD RAIN SHOWERS WILL BE ALONG AND JUST NORTH OF
THE 700-500MB VORT TRACK...WHICH LINES UP ACROSS OUR NRN
ADIRONDACK ZONES AND INTO S-CENTRAL VT. WITH WEAK INSTABILITY
DEVELOPING WITH COLD POOL ALOFT...FULLY EXPECT ACTIVITY TO BE
MORE WIDESPREAD DURING BOTH THURSDAY AND FRIDAY AFTN...WITH
ACTIVITY A BIT MORE CONCENTRATED NEAR THE UPR LOW DURING THE
OVERNIGHT PERIOD THURSDAY NIGHT. COULD BE COLD ENOUGH (WBZ
HEIGHTS 6-7 KFT) TO RESULT IN SOME PEA-SIZED HAIL WITH STRONGER
CORES BOTH THURSDAY AND FRIDAY AFTERNOONS. HAVE LEFT OUT SPECIFIC
MENTION OF THAT FOR NOW GIVEN WEAK INSTABILITY (<500 J/KG)...BUT
HAVE INCLUDED A SLIGHT CHANCE OF TSTMS FROM THE GREEN MTNS WWD ON
THURSDAY AFTN...AND AREAWIDE FRIDAY AFTN.
COVERAGE OF SHOWERS SHOULD DIMINISH NW-SE FRIDAY NIGHT AS UPR LOW
BEGINS TO DEPART SOUTHEAST OF NEW ENGLAND. WILL SHOW DRYING
CONDITIONS AND PARTIAL CLEARING IN THE FORECAST GRIDS FOR FRIDAY
NIGHT.
HYDROLOGICALLY...NEED TO BEWARE OF ANY POTENTIAL SURPRISE UNDER
THE UPPER LOW...BUT AT THIS POINT IT APPEARS HIGHEST RAINFALL
AMTS OF 1.0-1.5" WILL BE FOCUSED ACROSS NRN NY...AND NOT ENOUGH
TO RESULT IN FLOODING. GIVEN SATURATED CONDITIONS...THE BASIN TO
WATCH MOST CLOSELY WILL BE THE AUSABLE...WHICH ROSE TO NEAR 9
FEET (ASFN6) EARLY SUNDAY WITH THE LAST HVY RAIN PRODUCING
SYSTEM. THE RAINFALL WILL ALSO BE STRETCHED OUT ACROSS A 36-48
HOUR PERIOD. IN COMBINATION WITH ACTIVELY GROWING VEGETATION THIS
TIME OF YEAR...RUNOFF SHOULDN`T BE A SIGNIFICANT CONCERN GIVEN
CURRENT QPF EXPECTATIONS.
REMAINED CLOSE TO MOS CONSENSUS FOR DAYTIME HIGHS...GENERALLY UPR
60S TO LOWER 70S ON THURSDAY...AND MID-UPR 60S FRIDAY WITH COLD
POOL ALOFT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 412 AM EDT THURSDAY... OUR REGION IS UNDER A NORTHWEST FLOW
ALOFT THROUGH THE PERIOD LEAVING US BETWEEN A COOL CANADIAN
AIRMASS TO OUR EAST AND A WARM CONTINENTAL AIRMASS TO THE WEST.
THERE WILL BE SEVERAL DISTURBANCES IN THE FLOW ESPECIALLY SUNDAY
THROUGH TUESDAY BUT TEMPERATURES WILL BE AT OR SLIGHTY ABOVE
NORMAL FOR THIS TIME OF YEAR WITH HIGHS IN THE 70S AND LOWS IN THE
40S AND 50S.
MODELS ARE NOT IN GOOD AGREEMENT WITH THE DAILY FEATURES LEADING
TO BELOW AVERAGE CONFIDENCE IN THE WEATHER THIS PERIOD.
ONE SHORT WAVE TROUGH ALOFT WILL SLIDE SEWD ON SUNDAY WITH A WEAK
WARM FRONT DEVELOPING AT THE SURFACE...KEEPING A CHANCE OF
SHOWERS MAINLY FROM THE ADIRONDACKS ACROSS VT ON SUNDAY.
THIS IS WHERE THE MODEL DIVERGENCE STARTS GROWING WITH THE STRENGTH
OF THE UPPER LEVEL TROF. MODEL DIFFERENCES GROW FURTHER MONDAY
WITH WHICH AIRMASS WE WILL BE INFLUENCED BY MOST. HAVE LEANED
TOWARD A WARMER AND DRIER ECMWF SOLUTION WITH HIGHS WELL INTO THE
70S, BUT IT COULD EVEN BE WARMER IN THE LOWER 80S WITH 850 TEMPS AS
HIGH AS +12C CONTRASTED TO A COOLER +7 ON THE GFS WHICH WOULD
YIELD TEMPS CLOSER TO 70.
MONDAY NIGHT AND TUESDAY LOW PRESSURE AND ASSOCIATED COLD FRONT WILL
BRING ANOTHER CHANCE FOR SHOWERS, PERHAPS A THUNDERSTORM.
BY WEDNESDAY DESPITE DIFFERENCE IN UPPER LEVEL SOLUTIONS, IT
LOOKS LIKE NORMAL TEMPS AND VERY DRY AIRMASS FROM CANADA WILL MOVE
INTO THE AREA.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
THROUGH 06Z FRIDAY...EXPECTING MAINLY VFR CONDITIONS WITH
INCREASING COVERAGE OF SHOWERS THROUGH 00Z FRI AS SURFACE LOW
PRESSURE WILL BE NEARLY STATIONARY OVER NORTHERN NY WITH SE FLOW
OVER VT. AFT 00Z FRI...CIGS LOWERING TO MVFR WITH LIGHT WINDS AND
HIGH RELATIVE HUMIDITY LEADING TO BR LATE IN THE PERIOD AS SHOWERS
WIND DOWN.
ISOLATED SHOWERS AND A THUNDERSTORMS GOING EARLY THIS MORNING
MAINLY IN NY. COVERAGE IS SO LIMITED THAT WILL ONLY SHOW WITH VCSH
FOR NOW EXCEPT AT KSLK WHERE -SHRA PREVAIL.
SHOWERS AND POSSIBLE THUNDERSTORM DEVELOPMENT IS EXPECTED AFTER
13Z THURSDAY AT ALL TAF SITES WITH COVERAGE MORE WIDESPREAD BY
16-18Z WITH WEAK INSTABILITY. DID NOT INCLUDE THUNDER IN THE TAFS
AT THIS POINT AS PROBABILITY AT ANY POINT IS LOW.
CEILINGS/VISIBILITIES WILL BE PRIMARILY VFR...HOWEVER SOME
PERIODS OF REDUCTIONS TO MVFR OR EVEN IFR ARE POSSIBLE IN ANY
HEAVIER OR MORE ORGANIZED SHOWER ACTIVITY.
SOUTH/SOUTHEAST AT 5-10 KNOTS EXCEPT MSS WHERE NORTHEAST WINDS ARE
EXPECTED THROUGH THE PERIOD.
OUTLOOK 00Z FRIDAY THROUGH MONDAY...
06Z FRI THRU 12Z FRI...MVFR CIGS...LOCALLY IFR AT KMPV/KSLK IN STRATUS
AND FOG.
12Z FRI THRU 00Z SAT...IFR/MVFR EARLY BECOMING VFR/MVFR WITH SCATTERED
SHOWERS/THUNDERSTORMS.
00Z SAT THRU 00Z MON...MAINLY VFR WITH SCATTERED MVFR SHOWERS
SATURDAY AFTERNOON...AND ISOLATED SHOWERS SUNDAY AFTERNOON.
00Z MON ONWARD...GENERALLY DRY WITH VFR CONDITIONS UNDER SFC HIGH
PRESSURE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/JMG/NEILES
SHORT TERM...BANACOS
LONG TERM...SISSON
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
152 AM EDT THU MAY 22 2014
.SYNOPSIS...
AFTER A PLEASANTLY WARM AND DRY WEDNESDAY...AN UPPER-LEVEL
DISTURBANCE OVER THE NORTHERN GREAT LAKES WILL HAVE AN INCREASING
INFLUENCE ON OUR WEATHER AS IT SHIFTS SOUTHEASTWARD ACROSS NEW
YORK AND NEW ENGLAND THURSDAY AND FRIDAY. CLOUDS WILL BE ON THE
INCREASE OVERNIGHT TONIGHT...WITH A CHANCE FOR RAIN SHOWERS
TOWARD MORNING...MAINLY ACROSS NORTHERN NEW YORK AND INTO SOUTH-
CENTRAL VERMONT. SHOWERS WILL BECOME MORE WIDESPREAD ACROSS THE
REGION WITH DAYTIME HEATING ON THURSDAY. LOOK FOR MOSTLY CLOUDY
SKIES WITH NUMEROUS SLOW-MOVING SHOWERS...AND A SLIGHT CHANCE OF
AN AFTERNOON THUNDERSTORM. INTERVALS OF RAIN WILL CONTINUE
THURSDAY NIGHT INTO FRIDAY...WITH THE FOCUS FOR THE MOST
WIDESPREAD ACTIVITY EXPECTED ACROSS NORTHERN NEW YORK. DRIER
WEATHER WILL RETURN FOR THE WEEKEND AS THE UPPER LEVEL LOW SHIFTS
SOUTHEAST OF NEW ENGLAND AND A WEAK RIDGE OF HIGH PRESSURE BUILDS
IN ACROSS THE ST. LAWRENCE VALLEY.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 128 AM EDT THURSDAY...MAIN CHANGE FOR THIS LATEST UPDATE IS
TO RAISE MIN TEMPS AS WE ARE STILL 62 DEGREES HERE AT BTV. USED
THE MATCH LAV WHICH LOOKED GOOD. ALSO RAISED POPS A BIT WHERE
THERE ARE ALREADY SHOWERS ACROSS PARTS OF THE DACKS AND NORTHERN
NY. HAVE ADDED MENTION OF SLIGHT CHANCE THUNDER AS WELL WITH
THUNDERSTORM CURRENTLY MOVING INTO EXTREME WESTERN SAINT LAWRENCE
COUNTRY. PREVIOUS DISCUSSIONS FOLLOW.
ADDL SMALL ADJUSTMENTS TO POPS ACROSS THE AREA
OVERNIGHT...CONFINING ANY ISOLD/WIDELY SCT ACTIVITY TO OUR
SOUTHWESTERN COUNTIES AND LEAVING REMAINDER OF FORECAST AREA
GENERALLY DRY OVERNIGHT. CAN`T COMPLETELY RULE OUT ISOLD THUNDER
SOUTHWEST PER LATEST RAP SHOWALTER PROGS...BUT OMITTED MENTION
DUE TO EXPECTED PAUCITY OF COVERAGE. TEMPS/TD/SKY/WINDS REMAIN ON
TRACK SO NO OTHER CHANGES NEEDED AT THIS POINT. HAVE A GREAT
NIGHT. PRIOR DISCUSSIONS FOLLOW...
PRIOR DISCUSSION... A FEW UPDATES AS WE PROGRESS INTO THE EVENING
HOURS...MAINLY TO INTRODUCE A LOW CHANCE OF SHOWERS FOR THE
WESTERN SLOPES OF THE DACKS INTO THE SLV AND TO INCREASE CLOUD
COVER ACROSS THE AREA SOMEWHAT. CURRENT RADAR SHOWING ISOLD TO
WIDELY SCT SHOWERS HAVE DEVELOPED ACROSS PORTIONS OF THE SLV
EARLY THIS EVENING. SOME HEAVIER T-STORM ACTIVITY ALSO EVIDENT
FURTHER WEST ACROSS SOUTHERN ONTARIO INVOF PEMBROKE/RENFREW WHERE
LOCAL WARNINGS ARE IN EFFECT FROM ENV CANADA. NOT EXPECTING ANY
STORM ACTIVITY TO REACH OUR NRN NY COUNTIES THIS EVENING AS
AIRMASS REMAINS QUITE STABLE OVER OUR AREA. HOWEVER...A MID LEVEL
SHEAR ZONE HAS MATERIALIZED ACROSS THESE AREAS PER LATEST RAP
PROGS...AND WITH AT LEAST SOME SUPPORT FROM ~90KT UPPER LEVEL JET
TO THE IMMEDIATE SOUTHWEST...I LIKE THE MOST RECENT RAP/HRRR
PROGS SHOWING CONTINUED SCT SHOWER ACTIVITY IN THESE AREAS
OVERNIGHT AS MID LEVEL HEIGHTS SLOWLY FALL. MORE LIMITED ACTIVITY
NORTH AND EAST OF A KMSS-KBTV-KVSF LINE UNTIL LATER TONIGHT AS
THESE AREAS INITIALLY FURTHER REMOVED FROM BETTER MOISTURE/UPPER
LEVEL SUPPORT. DID OPT TO BLEND POPS FROM 06Z ONWARD INTO CURRENT
FORECAST AT 12Z...BUT IF CURRENT TRENDS CONTINUE MAY HAVE TO
ADJUST POPS FURTHER DOWNWARD NORTH AND EAST LATER TONIGHT. REST
OF FORECAST IN GOOD SHAPE AT THIS POINT.
PRIOR DISCUSSION... NARROW SFC RIDGE CENTERED ACROSS THE NORTH
COUNTRY RESULTING IN A PLEASANT AFTN WITH JUST SCATTERED FAIR
WEATHER CUMULUS CLOUDS DOTTING THE HIGHER TERRAIN PER AFTN
VISIBLE IMAGERY. 2-M TEMPS REACHED THE MID 70S (77F AT KBTV AT
1830Z) AS EXPECTED AREAWIDE...WITH DELIGHTFULLY LOW DEWPOINTS IN
THE 30S TO LOWER 40S. WINDS HAVE ALSO BEEN RATHER LIGHT IN VCNTY
OF PREVAILING SFC ANTICYCLONE. PLEASANT CONDITIONS WILL CONTINUE
THROUGH THIS EVENING WITH TEMPERATURES FALLING THROUGH THE 60S
WITH ONSET OF DIURNAL COOLING CYCLE.
SOME GRADUAL CHANGES WILL OCCUR LATE TONIGHT. THE 850MB FRONTAL
ZONE ACROSS SRN MI/NRN OH/PA...WHICH HAS BEEN THE FOCUS FOR
SHOWER AND TSTM ACTIVITY OVER THE PAST 12-24 HRS...WILL SLOWLY
LIFT NEWD...BUT IS ALSO EXPECTED TO SLOWLY WEAKEN. AT THE SAME
TIME ...MID-LEVEL HEIGHT FALLS ARE EXPECTED ACROSS NY/VT AS
CLOSED UPR LOW OVER THE NRN GREAT LAKES BEGINS TO SHIFT INTO SERN
ONTARIO OVERNIGHT. IT SHOULD REMAIN DRY THRU MIDNIGHT ALL
SECTIONS...BUT RESULT OF THE FRONTAL ZONE AND HEIGHT FALLS
SUGGESTS WE SHOULD BEGIN TO SEE SOME ISOLD/SCT SHOWER ACTIVITY
DEVELOP ACROSS OUR NRN NY COUNTIES SEWD INTO RUTLAND COUNTY AFTER
MIDNIGHT...AND ESPECIALLY AFTER 09Z. AIR MASS WILL REMAIN QUITE
DRY FURTHER NORTH AND EAST...SO ACTIVITY SHOULD REMAIN SOUTH AND
WEST OF THE CHAMPLAIN VALLEY THRU DAYBREAK BASED ON CURRENT
INDICATIONS. LOOK FOR A GRADUALLY INCREASE IN MID AND UPPER
LEVELS CLOUDS FROM THE CHAMPLAIN VALLEY NORTH AND EASTWARD LATE.
STAYED CLOSE TO MOS CONSENSUS FOR OVERNIGHT LOWS. WITH INCREASE
IN CLOUDS LATE...WILL SEE TEMPS A BIT WARMER THAN THE PREVIOUS
COUPLE OF NIGHTS. LOWS GENERALLY IN THE UPR 40S TO LOWER
50S...EXCEPT MID 40S FOR THE NORMALLY COOLER VALLEYS WITHIN THE
NRN ADIRONDACK REGION AND ACROSS FAR NERN VT. A LIGHT S-SE WIND
WILL DEVELOP OVERNIGHT AS SFC RIDGE SLIDES EWD INTO MAINE.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH FRIDAY NIGHT/...
AS OF 253 PM EDT WEDNESDAY...UNSETTLED WX CONDITIONS EXPECTED
THRU MUCH OF THE PERIOD. LOW-MID LEVEL LOW PRESSURE SYSTEM
ROTATES SEWD FROM SERN ONTARIO INTO THE ST. LAWRENCE VALLEY LATE
THURSDAY AFTN...AND THEN SLIDES SLOWLY SEWD ACROSS CENTRAL NEW
YORK STATE (JUST SOUTH OF THE ADIRONDACKS) AND SRN NEW ENGLAND
THURSDAY NIGHT THROUGH FRIDAY. MODELS CONTINUE TO INDICATE BEST
FOCUS FOR WIDESPREAD RAIN SHOWERS WILL BE ALONG AND JUST NORTH OF
THE 700-500MB VORT TRACK...WHICH LINES UP ACROSS OUR NRN
ADIRONDACK ZONES AND INTO S-CENTRAL VT. WITH WEAK INSTABILITY
DEVELOPING WITH COLD POOL ALOFT...FULLY EXPECT ACTIVITY TO BE
MORE WIDESPREAD DURING BOTH THURSDAY AND FRIDAY AFTN...WITH
ACTIVITY A BIT MORE CONCENTRATED NEAR THE UPR LOW DURING THE
OVERNIGHT PERIOD THURSDAY NIGHT. COULD BE COLD ENOUGH (WBZ
HEIGHTS 6-7 KFT) TO RESULT IN SOME PEA-SIZED HAIL WITH STRONGER
CORES BOTH THURSDAY AND FRIDAY AFTERNOONS. HAVE LEFT OUT SPECIFIC
MENTION OF THAT FOR NOW GIVEN WEAK INSTABILITY (<500 J/KG)...BUT
HAVE INCLUDED A SLIGHT CHANCE OF TSTMS FROM THE GREEN MTNS WWD ON
THURSDAY AFTN...AND AREAWIDE FRIDAY AFTN.
COVERAGE OF SHOWERS SHOULD DIMINISH NW-SE FRIDAY NIGHT AS UPR LOW
BEGINS TO DEPART SOUTHEAST OF NEW ENGLAND. WILL SHOW DRYING
CONDITIONS AND PARTIAL CLEARING IN THE FORECAST GRIDS FOR FRIDAY
NIGHT.
HYDROLOGICALLY...NEED TO BEWARE OF ANY POTENTIAL SURPRISE UNDER
THE UPPER LOW...BUT AT THIS POINT IT APPEARS HIGHEST RAINFALL
AMTS OF 1.0-1.5" WILL BE FOCUSED ACROSS NRN NY...AND NOT ENOUGH
TO RESULT IN FLOODING. GIVEN SATURATED CONDITIONS...THE BASIN TO
WATCH MOST CLOSELY WILL BE THE AUSABLE...WHICH ROSE TO NEAR 9
FEET (ASFN6) EARLY SUNDAY WITH THE LAST HVY RAIN PRODUCING
SYSTEM. THE RAINFALL WILL ALSO BE STRETCHED OUT ACROSS A 36-48
HOUR PERIOD. IN COMBINATION WITH ACTIVELY GROWING VEGETATION THIS
TIME OF YEAR...RUNOFF SHOULDN`T BE A SIGNIFICANT CONCERN GIVEN
CURRENT QPF EXPECTATIONS.
REMAINED CLOSE TO MOS CONSENSUS FOR DAYTIME HIGHS...GENERALLY UPR
60S TO LOWER 70S ON THURSDAY...AND MID-UPR 60S FRIDAY WITH COLD
POOL ALOFT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM EDT WEDNESDAY...AS SFC HIGH PRESSURE BUILDS OVER THE
CENTRAL GREAT LAKES REGION ON SATURDAY...AN UPPER LVL RIPPLE OF
ENERGY ALONG WITH SOME INSTABILITY WILL ALLOW FOR SCT RAIN
SHOWERS WITH PSBL TS OVER THE NORTH COUNTRY. THE SFC RIDGE WILL
SLIDE SEWD ON SUNDAY...WITH RIDING ALOFT GRADUALLY MOVING
EWD...PUTTING THE NORTH COUNTRY ON THE PERIPHERY OF HIGH
PRESSURE. THIS WILL CAUSE A DRYING TREND...BUT UPPER LVL
DISTURBANCE TRIES TO AFFECT THE AREA...SO CANNOT COMPLETELY RULE
OUT ISOLD-SCT SHOWERS OVER VT ON SUNDAY.
AS THE SFC RIDGE SLIDES INTO THE ATLANTIC OFF THE SERN USA...WE
WILL SEE A BRIEF DRY PERIOD SUNDAY NGT THROUGH MONDAY. SUNDAY
NGT...WEAKENING RIDGING ALOFT AND LOW PRESSURE SYSTEM AT THE SFC
WILL BRING ANOTHER CHANCE FOR SHOWERS...ESP ON TUESDAY.
THIS ACTIVE PATTERN WILL SEE TEMPS ABOVE NORMAL WITH GENERAL
WARMING TREND. SATURDAY...BEING THE COOLEST DAY WILL HAVE MAX
TEMPS IN THE 50S ACROSS THE MTNS AND 60S-AROUND 70 IN THE
VALLEYS. WARMEST DAY LOOKS TO BE MONDAY WITH MTNS IN THE 60S AND
VALLEYS IN THE L70S-L80S. TUESDAY AND WEDNESDAY CONTINUE TO BE
MILD. AT NIGHT...MIN TEMPS WILL RANGE FROM 40S-L50S IN THE MTNS
AND 50S IN THE VALLEYS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THROUGH 06Z FRIDAY...EXPECTING MAINLY VFR CONDITIONS WITH
INCREASING COVERAGE OF SHOWERS THROUGH 00Z FRI AS SURFACE LOW
PRESSURE WILL BE NEARLY STATIONARY OVER NORTHERN NY WITH SE FLOW
OVER VT. AFT 00Z FRI...CIGS LOWERING TO MVFR WITH LIGHT WINDS AND
HIGH RELATIVE HUMIDITY LEADING TO BR LATE IN THE PERIOD AS SHOWERS
WIND DOWN.
ISOLATED SHOWERS AND A THUNDERSTORMS GOING EARLY THIS MORNING
MAINLY IN NY. COVERAGE IS SO LIMITED THAT WILL ONLY SHOW WITH VCSH
FOR NOW EXCEPT AT KSLK WHERE -SHRA PREVAIL.
SHOWERS AND POSSIBLE THUNDERSTORM DEVELOPMENT IS EXPECTED AFTER
13Z THURSDAY AT ALL TAF SITES WITH COVERAGE MORE WIDESPREAD BY
16-18Z WITH WEAK INSTABILITY. DID NOT INCLUDE THUNDER IN THE TAFS
AT THIS POINT AS PROBABILITY AT ANY POINT IS LOW.
CEILINGS/VISIBILITIES WILL BE PRIMARILY VFR...HOWEVER SOME
PERIODS OF REDUCTIONS TO MVFR OR EVEN IFR ARE POSSIBLE IN ANY
HEAVIER OR MORE ORGANIZED SHOWER ACTIVITY.
SOUTH/SOUTHEAST AT 5-10 KNOTS EXCEPT MSS WHERE NORTHEAST WINDS ARE
EXPECTED THROUGH THE PERIOD.
OUTLOOK 00Z FRIDAY THROUGH MONDAY...
06Z FRI THRU 12Z FRI...MVFR CIGS...LOCALLY IFR AT KMPV/KSLK IN STRATUS
AND FOG.
12Z FRI THRU 00Z SAT...IFR/MVFR EARLY BECOMING VFR/MVFR WITH SCATTERED
SHOWERS/THUNDERSTORMS.
00Z SAT THRU 00Z MON...MAINLY VFR WITH SCATTERED MVFR SHOWERS
SATURDAY AFTERNOON...AND ISOLATED SHOWERS SUNDAY AFTERNOON.
00Z MON ONWARD...GENERALLY DRY WITH VFR CONDITIONS UNDER SFC HIGH
PRESSURE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/JMG/NEILES
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
134 AM EDT THU MAY 22 2014
.SYNOPSIS...
AFTER A PLEASANTLY WARM AND DRY WEDNESDAY...AN UPPER-LEVEL
DISTURBANCE OVER THE NORTHERN GREAT LAKES WILL HAVE AN INCREASING
INFLUENCE ON OUR WEATHER AS IT SHIFTS SOUTHEASTWARD ACROSS NEW
YORK AND NEW ENGLAND THURSDAY AND FRIDAY. CLOUDS WILL BE ON THE
INCREASE OVERNIGHT TONIGHT...WITH A CHANCE FOR RAIN SHOWERS
TOWARD MORNING...MAINLY ACROSS NORTHERN NEW YORK AND INTO SOUTH-
CENTRAL VERMONT. SHOWERS WILL BECOME MORE WIDESPREAD ACROSS THE
REGION WITH DAYTIME HEATING ON THURSDAY. LOOK FOR MOSTLY CLOUDY
SKIES WITH NUMEROUS SLOW-MOVING SHOWERS...AND A SLIGHT CHANCE OF
AN AFTERNOON THUNDERSTORM. INTERVALS OF RAIN WILL CONTINUE
THURSDAY NIGHT INTO FRIDAY...WITH THE FOCUS FOR THE MOST
WIDESPREAD ACTIVITY EXPECTED ACROSS NORTHERN NEW YORK. DRIER
WEATHER WILL RETURN FOR THE WEEKEND AS THE UPPER LEVEL LOW SHIFTS
SOUTHEAST OF NEW ENGLAND AND A WEAK RIDGE OF HIGH PRESSURE BUILDS
IN ACROSS THE ST. LAWRENCE VALLEY.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 128 AM EDT THURSDAY...MAIN CHANGE FOR THIS LATEST UPDATE IS
TO RAISE MIN TEMPS AS WE ARE STILL 62 DEGREES HERE AT BTV. USED
THE MATCH LAV WHICH LOOKED GOOD. ALSO RAISED POPS A BIT WHERE
THERE ARE ALREADY SHOWERS ACROSS PARTS OF THE DACKS AND NORTHERN
NY. HAVE ADDED MENTION OF SLIGHT CHANCE THUNDER AS WELL WITH
THUNDERSTORM CURRENTLY MOVING INTO EXTREME WESTERN SAINT LAWRENCE
COUNTRY. PREVIOUS DISCUSSIONS FOLLOW.
ADDL SMALL ADJUSTMENTS TO POPS ACROSS THE AREA
OVERNIGHT...CONFINING ANY ISOLD/WIDELY SCT ACTIVITY TO OUR
SOUTHWESTERN COUNTIES AND LEAVING REMAINDER OF FORECAST AREA
GENERALLY DRY OVERNIGHT. CAN`T COMPLETELY RULE OUT ISOLD THUNDER
SOUTHWEST PER LATEST RAP SHOWALTER PROGS...BUT OMITTED MENTION
DUE TO EXPECTED PAUCITY OF COVERAGE. TEMPS/TD/SKY/WINDS REMAIN ON
TRACK SO NO OTHER CHANGES NEEDED AT THIS POINT. HAVE A GREAT
NIGHT. PRIOR DISCUSSIONS FOLLOW...
PRIOR DISCUSSION... A FEW UPDATES AS WE PROGRESS INTO THE EVENING
HOURS...MAINLY TO INTRODUCE A LOW CHANCE OF SHOWERS FOR THE
WESTERN SLOPES OF THE DACKS INTO THE SLV AND TO INCREASE CLOUD
COVER ACROSS THE AREA SOMEWHAT. CURRENT RADAR SHOWING ISOLD TO
WIDELY SCT SHOWERS HAVE DEVELOPED ACROSS PORTIONS OF THE SLV
EARLY THIS EVENING. SOME HEAVIER T-STORM ACTIVITY ALSO EVIDENT
FURTHER WEST ACROSS SOUTHERN ONTARIO INVOF PEMBROKE/RENFREW WHERE
LOCAL WARNINGS ARE IN EFFECT FROM ENV CANADA. NOT EXPECTING ANY
STORM ACTIVITY TO REACH OUR NRN NY COUNTIES THIS EVENING AS
AIRMASS REMAINS QUITE STABLE OVER OUR AREA. HOWEVER...A MID LEVEL
SHEAR ZONE HAS MATERIALIZED ACROSS THESE AREAS PER LATEST RAP
PROGS...AND WITH AT LEAST SOME SUPPORT FROM ~90KT UPPER LEVEL JET
TO THE IMMEDIATE SOUTHWEST...I LIKE THE MOST RECENT RAP/HRRR
PROGS SHOWING CONTINUED SCT SHOWER ACTIVITY IN THESE AREAS
OVERNIGHT AS MID LEVEL HEIGHTS SLOWLY FALL. MORE LIMITED ACTIVITY
NORTH AND EAST OF A KMSS-KBTV-KVSF LINE UNTIL LATER TONIGHT AS
THESE AREAS INITIALLY FURTHER REMOVED FROM BETTER MOISTURE/UPPER
LEVEL SUPPORT. DID OPT TO BLEND POPS FROM 06Z ONWARD INTO CURRENT
FORECAST AT 12Z...BUT IF CURRENT TRENDS CONTINUE MAY HAVE TO
ADJUST POPS FURTHER DOWNWARD NORTH AND EAST LATER TONIGHT. REST
OF FORECAST IN GOOD SHAPE AT THIS POINT.
PRIOR DISCUSSION... NARROW SFC RIDGE CENTERED ACROSS THE NORTH
COUNTRY RESULTING IN A PLEASANT AFTN WITH JUST SCATTERED FAIR
WEATHER CUMULUS CLOUDS DOTTING THE HIGHER TERRAIN PER AFTN
VISIBLE IMAGERY. 2-M TEMPS REACHED THE MID 70S (77F AT KBTV AT
1830Z) AS EXPECTED AREAWIDE...WITH DELIGHTFULLY LOW DEWPOINTS IN
THE 30S TO LOWER 40S. WINDS HAVE ALSO BEEN RATHER LIGHT IN VCNTY
OF PREVAILING SFC ANTICYCLONE. PLEASANT CONDITIONS WILL CONTINUE
THROUGH THIS EVENING WITH TEMPERATURES FALLING THROUGH THE 60S
WITH ONSET OF DIURNAL COOLING CYCLE.
SOME GRADUAL CHANGES WILL OCCUR LATE TONIGHT. THE 850MB FRONTAL
ZONE ACROSS SRN MI/NRN OH/PA...WHICH HAS BEEN THE FOCUS FOR
SHOWER AND TSTM ACTIVITY OVER THE PAST 12-24 HRS...WILL SLOWLY
LIFT NEWD...BUT IS ALSO EXPECTED TO SLOWLY WEAKEN. AT THE SAME
TIME ...MID-LEVEL HEIGHT FALLS ARE EXPECTED ACROSS NY/VT AS
CLOSED UPR LOW OVER THE NRN GREAT LAKES BEGINS TO SHIFT INTO SERN
ONTARIO OVERNIGHT. IT SHOULD REMAIN DRY THRU MIDNIGHT ALL
SECTIONS...BUT RESULT OF THE FRONTAL ZONE AND HEIGHT FALLS
SUGGESTS WE SHOULD BEGIN TO SEE SOME ISOLD/SCT SHOWER ACTIVITY
DEVELOP ACROSS OUR NRN NY COUNTIES SEWD INTO RUTLAND COUNTY AFTER
MIDNIGHT...AND ESPECIALLY AFTER 09Z. AIR MASS WILL REMAIN QUITE
DRY FURTHER NORTH AND EAST...SO ACTIVITY SHOULD REMAIN SOUTH AND
WEST OF THE CHAMPLAIN VALLEY THRU DAYBREAK BASED ON CURRENT
INDICATIONS. LOOK FOR A GRADUALLY INCREASE IN MID AND UPPER
LEVELS CLOUDS FROM THE CHAMPLAIN VALLEY NORTH AND EASTWARD LATE.
STAYED CLOSE TO MOS CONSENSUS FOR OVERNIGHT LOWS. WITH INCREASE
IN CLOUDS LATE...WILL SEE TEMPS A BIT WARMER THAN THE PREVIOUS
COUPLE OF NIGHTS. LOWS GENERALLY IN THE UPR 40S TO LOWER
50S...EXCEPT MID 40S FOR THE NORMALLY COOLER VALLEYS WITHIN THE
NRN ADIRONDACK REGION AND ACROSS FAR NERN VT. A LIGHT S-SE WIND
WILL DEVELOP OVERNIGHT AS SFC RIDGE SLIDES EWD INTO MAINE.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH FRIDAY NIGHT/...
AS OF 253 PM EDT WEDNESDAY...UNSETTLED WX CONDITIONS EXPECTED
THRU MUCH OF THE PERIOD. LOW-MID LEVEL LOW PRESSURE SYSTEM
ROTATES SEWD FROM SERN ONTARIO INTO THE ST. LAWRENCE VALLEY LATE
THURSDAY AFTN...AND THEN SLIDES SLOWLY SEWD ACROSS CENTRAL NEW
YORK STATE (JUST SOUTH OF THE ADIRONDACKS) AND SRN NEW ENGLAND
THURSDAY NIGHT THROUGH FRIDAY. MODELS CONTINUE TO INDICATE BEST
FOCUS FOR WIDESPREAD RAIN SHOWERS WILL BE ALONG AND JUST NORTH OF
THE 700-500MB VORT TRACK...WHICH LINES UP ACROSS OUR NRN
ADIRONDACK ZONES AND INTO S-CENTRAL VT. WITH WEAK INSTABILITY
DEVELOPING WITH COLD POOL ALOFT...FULLY EXPECT ACTIVITY TO BE
MORE WIDESPREAD DURING BOTH THURSDAY AND FRIDAY AFTN...WITH
ACTIVITY A BIT MORE CONCENTRATED NEAR THE UPR LOW DURING THE
OVERNIGHT PERIOD THURSDAY NIGHT. COULD BE COLD ENOUGH (WBZ
HEIGHTS 6-7 KFT) TO RESULT IN SOME PEA-SIZED HAIL WITH STRONGER
CORES BOTH THURSDAY AND FRIDAY AFTERNOONS. HAVE LEFT OUT SPECIFIC
MENTION OF THAT FOR NOW GIVEN WEAK INSTABILITY (<500 J/KG)...BUT
HAVE INCLUDED A SLIGHT CHANCE OF TSTMS FROM THE GREEN MTNS WWD ON
THURSDAY AFTN...AND AREAWIDE FRIDAY AFTN.
COVERAGE OF SHOWERS SHOULD DIMINISH NW-SE FRIDAY NIGHT AS UPR LOW
BEGINS TO DEPART SOUTHEAST OF NEW ENGLAND. WILL SHOW DRYING
CONDITIONS AND PARTIAL CLEARING IN THE FORECAST GRIDS FOR FRIDAY
NIGHT.
HYDROLOGICALLY...NEED TO BEWARE OF ANY POTENTIAL SURPRISE UNDER
THE UPPER LOW...BUT AT THIS POINT IT APPEARS HIGHEST RAINFALL
AMTS OF 1.0-1.5" WILL BE FOCUSED ACROSS NRN NY...AND NOT ENOUGH
TO RESULT IN FLOODING. GIVEN SATURATED CONDITIONS...THE BASIN TO
WATCH MOST CLOSELY WILL BE THE AUSABLE...WHICH ROSE TO NEAR 9
FEET (ASFN6) EARLY SUNDAY WITH THE LAST HVY RAIN PRODUCING
SYSTEM. THE RAINFALL WILL ALSO BE STRETCHED OUT ACROSS A 36-48
HOUR PERIOD. IN COMBINATION WITH ACTIVELY GROWING VEGETATION THIS
TIME OF YEAR...RUNOFF SHOULDN`T BE A SIGNIFICANT CONCERN GIVEN
CURRENT QPF EXPECTATIONS.
REMAINED CLOSE TO MOS CONSENSUS FOR DAYTIME HIGHS...GENERALLY UPR
60S TO LOWER 70S ON THURSDAY...AND MID-UPR 60S FRIDAY WITH COLD
POOL ALOFT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM EDT WEDNESDAY...AS SFC HIGH PRESSURE BUILDS OVER THE
CENTRAL GREAT LAKES REGION ON SATURDAY...AN UPPER LVL RIPPLE OF
ENERGY ALONG WITH SOME INSTABILITY WILL ALLOW FOR SCT RAIN
SHOWERS WITH PSBL TS OVER THE NORTH COUNTRY. THE SFC RIDGE WILL
SLIDE SEWD ON SUNDAY...WITH RIDING ALOFT GRADUALLY MOVING
EWD...PUTTING THE NORTH COUNTRY ON THE PERIPHERY OF HIGH
PRESSURE. THIS WILL CAUSE A DRYING TREND...BUT UPPER LVL
DISTURBANCE TRIES TO AFFECT THE AREA...SO CANNOT COMPLETELY RULE
OUT ISOLD-SCT SHOWERS OVER VT ON SUNDAY.
AS THE SFC RIDGE SLIDES INTO THE ATLANTIC OFF THE SERN USA...WE
WILL SEE A BRIEF DRY PERIOD SUNDAY NGT THROUGH MONDAY. SUNDAY
NGT...WEAKENING RIDGING ALOFT AND LOW PRESSURE SYSTEM AT THE SFC
WILL BRING ANOTHER CHANCE FOR SHOWERS...ESP ON TUESDAY.
THIS ACTIVE PATTERN WILL SEE TEMPS ABOVE NORMAL WITH GENERAL
WARMING TREND. SATURDAY...BEING THE COOLEST DAY WILL HAVE MAX
TEMPS IN THE 50S ACROSS THE MTNS AND 60S-AROUND 70 IN THE
VALLEYS. WARMEST DAY LOOKS TO BE MONDAY WITH MTNS IN THE 60S AND
VALLEYS IN THE L70S-L80S. TUESDAY AND WEDNESDAY CONTINUE TO BE
MILD. AT NIGHT...MIN TEMPS WILL RANGE FROM 40S-L50S IN THE MTNS
AND 50S IN THE VALLEYS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THROUGH 00Z FRIDAY...EXPECTING VFR CONDITIONS FOR THE MAJORITY OF
THE PERIOD...WITH SCATTERED BRIEF PERIODS OF MVFR/IFR POSSIBLE.
SCATTERED VFR CLOUDS WITH CEILINGS 10000 FEET OR ABOVE WILL
GRADUALLY INCREASE IN COVERAGE AND LOWER THROUGH THE NIGHT AND
EARLY THURSDAY MORNING. SOME ISOLATED SHOWERS THIS EVENING AND
TONIGHT ARE POSSIBLE AT MSS/SLK/RUT BUT COVERAGE IS SO LIMITED
THAT WILL ONLY SHOW WITH VCSH FOR NOW. ADDITIONAL MORE WIDESPREAD
SHOWER AND POSSIBLE THUNDERSTORM DEVELOPMENT IS EXPECTED AFTER
14Z THURSDAY AT ALL TAF SITES. CEILINGS/VISIBILITIES WILL BE
PRIMARILY VFR...HOWEVER SOME PERIODS OF REDUCTIONS TO MVFR OR
EVEN IFR ARE POSSIBLE IN ANY HEAVIER OR MORE ORGANIZED SHOWER
ACTIVITY. WINDS WILL BE LIGHT AND LOCALLY VARIABLE
TONIGHT...BECOMING GENERALLY SOUTH/SOUTHEAST AT 5-10 KNOTS ON
THURSDAY...EXCEPT MSS WHERE NORTHEAST WINDS ARE EXPECTED THROUGH
THE PERIOD.
OUTLOOK 00Z FRIDAY THROUGH MONDAY...
00Z FRI THRU 00Z SAT...PRIMARILY VFR ALTHOUGH REDUCTIONS TO
MVFR/IFR AT TIMES IN SCATTERED SHOWERS/THUNDERSTORMS.
00Z SAT THRU 00Z MON...MAINLY VFR WITH SCATTERED MVFR SHOWERS
SATURDAY AFTERNOON...AND ISOLATED SHOWERS SUNDAY AFTERNOON.
00Z MON ONWARD...GENERALLY DRY WITH VFR CONDITIONS UNDER SFC HIGH
PRESSURE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/JMG/NEILES
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...KGM/MUCCILLI
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
143 AM EDT THU MAY 22 2014
.SYNOPSIS...
WARM AND MAINLY DRY CONDITIONS WILL CONTINUE AS HIGH PRESSURE
REMAINS TO THE SOUTH. AFTER A VERY WARM DAY THURSDAY...A COLD
FRONT WILL DROP SOUTH ON FRIDAY...AND WILL STALL JUST SOUTH OF THE
AREA THROUGH THE WEEKEND. TEMPERATURES BEHIND THIS FRONT WILL BE
COOLER...BUT SEASONABLE AND DRY CONDITIONS ARE EXPECTED INTO THE
MEMORIAL DAY HOLIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:40 AM THURSDAY...HAVE NOT MADE ANY CHANGES TO THE FORECAST
AND WILL FOR THE MOMENT CONTINUE WITH SLIGHT CHANCE POPS FOR THE
OVERNIGHT PERIOD...BUT WILL LIKELY DROP THEM WITH THE NEXT
ISSUANCE IF CURRENT TRENDS CONTINUE. MCS DROPPING SE ACROSS THE
MOUNTAINS IS ERODING RAPIDLY AND IT IS LOOKING LESS LIKELY THAT WE
WILL GET MUCH MORE THAN SOME MID-LEVEL CLOUDS. PREVIOUS
DISCUSSIONS FOLLOW:
I HAVE TRIMMED BACK POPS A LITTLE MORE BASED MAINLY ON DATA
COLLECTED FROM THE 00Z GSO WEATHER BALLOON SHOWING A 3 DEGREE
CELSIUS INVERSION BETWEEN 11000-12000 FEET. THIS WOULD TEND TO CAP
OFF ANY CUMULUS GROWING FROM BELOW. EACH RUN OF THE HRRR MODEL
CONTINUES TO SHOW SCATTERED SHOWERS DEVELOPING AROUND MIDNIGHT
ACROSS EASTERN NC...BUT THIS SEEMS THERMODYNAMICALLY UNLIKELY
GIVEN THE WEATHER BALLOON DATA. NO OTHER SIGNIFICANT CHANGES.
PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
SURFACE HIGH PRESSURE OFF THE FL/GA COAST IS PRODUCING A STEADY SW
BREEZE...STRONGEST NEAR THE COAST WHERE SEABREEZE INFLUENCE HAS
INCREASED WIND SPEEDS TO NEAR 20 MPH. ALOFT THE FLOW IS STRONGLY
VEERED TO THE NW AT AND ABOVE 850 MB DUE TO THE MID AND UPPER LEVEL
RIDGE STILL CENTERED BACK OVER THE LOWER MISSISSIPPI VALLEY.
THE CONCERN FOR TONIGHT IS HOW MUCH INFLUENCE THE EASTERN CAROLINAS
GET FROM A DEVELOPING MCS ACROSS THE OHIO VALLEY. MODELS ALL SHOW
THIS ACTIVITY MAKING INTO THE NC/VA MOUNTAINS LATER THIS EVENING...
BUT THE MOUNTAINS MAY TAKE THEIR TOLL ON THE STORMS AS HIGH-RES
MODEL DEPICTIONS SHOW ONLY LIMITED CONVECTION SURVIVING THROUGH THE
PIEDMONT AND COASTAL PLAIN. LAPSE RATES ALOFT ARE STEEP...TONIGHT`S
850 MB TEMP OF +17C VERSUS A 500 MB TEMP OF -11C TELLS THAT PART OF
THE STORY. COUPLED LOW AND MID LEVEL LIFT AHEAD OF AN UPPER LEVEL
DISTURBANCE EMBEDDED IN THE NW FLOW ALOFT WILL SERVE AS THE
CONVECTIVE TRIGGER...BUT THE LIMITING FACTOR WILL BE HOW MUCH
MOISTURE CAN POOL AT THE BASE OF THE STEEP LAPSE RATES NEAR 850 MB?
MODELS DEFINITELY SHOW MORE 850 MB MOISTURE ACROSS NC THAN SC...AND
GIVEN THIS LIMITED "THUNDERSTORM FUEL" OVER SC I HAVE REMOVED POPS
THERE. IF ACTIVITY CAN SURVIVE THIS FAR SOUTH AND EAST THE WINDOW OF
THUNDERSTORM POTENTIAL WILL BE FROM MIDNIGHT UNTIL 4 AM...GENERALLY
ALONG AND NORTH OF A LINE FROM BENNETTSVILLE THROUGH DILLON...
WHITEVILLE...OAK ISLAND AND SOUTHPORT.
THE PRESENCE OF PERIODS OF CIRRUS CLOUD COVER PLUS THE SOUTHWEST
BREEZE MUCH OF THE NIGHT SHOULD HELP KEEP LOWS IN THE UPPER 60S
INLAND TO NEAR 70 ON THE COAST. THIS IS A LITTLE ABOVE THE WARMEST
MOS GUIDANCE AND NEAR THE BIAS-CORRECTED GFS NUMBERS.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
AS OF 240 PM WEDNESDAY...ALTHOUGH THE 500 MB RIDGE WILL REMAIN
CENTERED OVER THE GULF COAST STATES THURSDAY...IT WILL SHIFT EAST
ENOUGH TO RESULT IN HEIGHT RISES OVER THE CAROLINAS...AS WELL AS
THE EXPANSION OF UNSEASONABLY HOT AIR INTO THE AREA. MODELS STILL
INDICATE 850 MB TEMPS TO 18C AS FAR NORTH AS THE NC-SC STATE LINE.
12Z GUIDANCE IS CONSISTENT AND REMAINS IN LINE WITH GOING FORECAST
OF LOW TO MID 90S EVERYWHERE AWAY FROM THE IMMEDIATE COAST...WHERE
HIGHS ARE EXPECTED TO REACH THE MID 80S. CAN`T RULE OUT A LATE
AFTERNOON OR EVENING THUNDERSTORM GIVEN THE STRONG HEATING AND
WEAK CONVERGENCE ALONG A SURFACE TROUGH INLAND.
A 500 MB SHORTWAVE WILL HELP USHER THE TROUGH/FRONT SOUTH THROUGH
THE CWA THURSDAY NIGHT...AND SURFACE HIGH PRESSURE WILL BUILD IN
FROM THE NORTHWEST. THE SHORTWAVE WILL FLATTEN OUT THE MID-LEVEL
RIDGING OVER THE AREA...THEREFORE MAX TEMPS FRIDAY WILL FALL BACK
A FEW DEGREES. ISOLATED CONVECTION WILL REMAIN A POSSIBILITY GIVEN
ANOTHER DAY OF STRONG HEATING AND NORTHWESTERLY FLOW ALOFT.
TIME-HEIGHT CROSS SECTIONS CONTINUE TO INDICATE RAPID DRYING OF
THE COLUMN UNDERWAY BY 06Z SATURDAY. THEREFORE METEOR SHOWER
ENTHUSIASTS HAVE REASON TO BE OPTIMISTIC AS LOW/MID CLOUDS SHOULD
NOT IMPEDE VISIBILITY LATE FRIDAY NIGHT. CAN`T RULE OUT A THIN
LAYER OF CIRRUS HOWEVER.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 240 PM WEDNESDAY...FAIRLY DEEP UPPER TROUGH FORMS OFF NEW
ENGLAND COAST OVER THE WEEKEND DRIVING A VERY PLEASANT AIRMASS
INTO THE SOUTHEASTERN U.S. TEMPERATURE DEVIATIONS FROM CLIMATOLOGY
WILL BE MORE PRONOUNCED AT NIGHT THAN BY DAY...AND THE LOWERED RH
WILL BE VERY NOTICEABLE. UPPER RIDGE BUILDS OVERHEAD ON MONDAY AND
SOME LIGHT RETURN FLOW MAY GET UNDERWAY. THIS SHOULD TRANSLATE TO
A WARMING TREND AS WELL AS AN INCREASE IN DEWPOINTS/RH. A
FLATTENING OF THE RIDGE ALOFT PAIRED WITH THE FORMATION OF A
PIEDMONT TROUGH CALLS FOR LOW CHANCES OF MAINLY DIURNAL
CONVECTION. TEMPERATURES WILL BE VERY NEAR CLIMATOLOGY NEXT WEEK.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...EXPECT VFR TO PREVAIL THROUGH THE VALID TAF PERIOD.
LATEST SATELLITE IMAGERY CONTINUES TO DEPICT MID TO HIGH CLOUDS TO
THE NORTHWEST IN CORRELATION WITH THUNDERSTORM ACTIVITY SLOWLY
MOVING SOUTHEAST TOWARDS THE AREA. WHILE COULD NOT COMPLETELY RULE
OUT AN ISOLATED SHOWER OR THUNDERSTORM MUCH LATER TONIGHT INTO THE
EARLY OVERNIGHT HOURS AT KLBT/KILM PER SUGGESTION OF SOME MODEL
GUIDANCE...CONFIDENCE IS LOW GIVEN INTERACTION WITH APPALACHIAN
MOUNTAINS AND THUS DO NOT EXPECT ANY RESTRICTIONS TO OCCUR AS A
RESULT. AS FOR WINDS CAN EXPECT SOUTHWEST WINDS BECOMING AOB 10 KTS
THROUGH THE OVERNIGHT HOURS. AFTER DAYBREAK...EXPECT VFR WITH THE
POSSIBILITY OF ISOLATED TO SCATTERED AFTERNOON SHRA/TSRA. WESTERLY
WINDS WILL PREVAIL WITH SUSTAINED WINDS INCREASING TO AOB 12 KTS
WITH AFTERNOON GUSTS POSSIBLE...SUBSIDING INTO THE EVENING HOURS.
EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD.
CHANCE OF SHOWERS THURSDAY THROUGH SATURDAY MORNING WITH A COLD
FRONT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:40 AM THURSDAY...NO SIGNIFICANT CHANGES HAVE BEEN MADE WITH
THIS UPDATE. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS:
HIGH PRESSURE EAST OF THE GA/FL COAST IS MAINTAINING A HEALTHY
SOUTHWEST WIND ACROSS THE COASTAL WATERS. ADD IN SOME EXTRA WIND
FROM THE AFTERNOON SEABREEZE AND WE`RE SEEING A SOLID 20 KNOTS
ACROSS MOST OF THE COASTAL WATERS CURRENTLY. WINDS ACROSS THE SC
WATERS SHOULD NOT INCREASE TONIGHT AND WILL ACTUALLY DIMINISH AFTER
MIDNIGHT AS WIND DIRECTIONS TURN MORE WESTERLY IN ASSOCIATION WITH
AN UPPER LEVEL DISTURBANCE PASSING THROUGH TO OUR NORTH. ACROSS THE
NC WATERS WINDS MAY INCREASE ANOTHER 3-5 KNOTS BY MIDNIGHT AHEAD OF
THE UPPER DISTURBANCE...BUT EVEN HERE SHOULD DIMINISH LATE TONIGHT
AS DIRECTIONS TURN WESTERLY.
I HAVE MAINTAINED THE SMALL CRAFT ADVISORY FOR THE NC WATERS WHERE
SEAS SHOULD BUILD TO 5-6 FEET OUT BEYOND 10 MILES FROM SHORE...
ESPECIALLY JUST EAST OF BALD HEAD ISLAND WHERE THE EFFECTIVE FETCH
LENGTH IS QUITE LONG ON A SW WIND.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 240 PM WEDNESDAY...LOW PRESSURE MOVING EAST OFF THE
DELMARVA PENINSULA WILL COMBINE WITH HIGH PRESSURE OVER THE GULF
COAST TO PRODUCE WESTERLY WINDS ACROSS THE AREA WATERS. THE
GRADIENT WILL WEAKEN THROUGH THE DAY AS THE LOW MOVES TO THE EAST.
A WEAK SURFACE TROUGH/FRONT WILL DROP SOUTH ACROSS THE WATERS
THURSDAY NIGHT RESULTING IN A SHIFT TO NORTHERLY WINDS. THE
GRADIENT WILL TEMPORARILY WASH OUT FRIDAY WITH WINDS BECOMING
VARIABLE. HIGH PRESSURE WILL PUSH ACROSS THE CAROLINAS FRIDAY
NIGHT AND RESULT IN A LATE NIGHT NORTHERLY SURGE TO 15-20 KTS.
WILL HAVE TO MONITOR THE PROGRESSION OF ANY CONVECTION THAT
DEVELOPS INLAND BOTH THURSDAY AND FRIDAY...AS DEEP NORTHWEST FLOW
COULD PUSH THIS ACTIVITY ACROSS THE COASTAL WATERS.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 240 PM WEDNESDAY...N TO NE WINDS ON SATURDAY WILL FOLLOW IN
THE WAKE OF FRIDAY COLD FRONT. FLOW WILL REMAIN LIGHT...NO SURGE
OF COOLER AIR OR HIGHER PRESSURES NORMALLY ASSOCIATED WITH COOL
SEASON FROPAS. CENTER OF HIGH PRESSURE DRAWS NEARER BUT REMAINS TO
OUR NORTH ON SUNDAY LEADING TO A VEER TO AN ONSHORE/EASTERLY FLOW.
WIND SPEEDS REMAIN EXCEEDINGLY LIGHT BUT WILL SEE A LOCALIZED
ACCELERATION OF A FEW KNOTS ALONG THE IMMEDIATE COAST DUE TO SEA
BREEZE CIRCULATION. VEERING WINDS/CLOCKWISE CHANGE IN DIRECTION
CONTINUES INTO MONDAY AS THE CENTER OF THE HIGH PROGRESSES
EASTWARD. NOT SEEING ANY APPRECIABLE INCREASE IN WIND SPEED BUT
THE LONGER FETCH SETTING UP MAY ALLOW FOR A VERY MINOR SWELL
COMPONENT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR
AMZ250-252.
&&
$$
SYNOPSIS...SHK
NEAR TERM...SHK
SHORT TERM...CRM
LONG TERM...MBB
AVIATION...SGL
MARINE...MBB/SHK/CRM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1008 AM CDT THU MAY 22 2014
.UPDATE...
ISSUED AT 1009 AM CDT THU MAY 22 2014
LATEST RAP/NAM ARE SHOWING SOME LOW TO MID LEVEL MOISTURE UNDER
THE UPPER LEVEL RIDGE SITUATED OVER THE CENTRAL DAKOTAS. THIS IS
RESULTING IN SOME HIGHER CLOUD COVER SOUTHWEST AND SOUTH CENTRAL
NORTH DAKOTA. THUS BUMPED UP CLOUD COVER MAINLY ALONG AND SOUTH OF
THE INTERSTATE TODAY. OTHERWISE UPDATED LATEST SENSIBLE WEATHER
GRIDS.
UPDATE ISSUED AT 635 AM CDT THU MAY 22 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. VERY PATCHY FOG
HAS DEVELOPED ACROSS THE TURTLE MOUNTAINS AND THROUGH THE JAMES
RIVER VALLEY AS OF 1130 UTC. HOWEVER...WITH INSOLATION INCREASING
IT SHOULD BE VERY SHORT LIVED AND LEFT IT OUT OF THE FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 359 AM CDT THU MAY 22 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE SLIGHT
CHANCES FOR A THUNDERSTORM SOUTHWEST LATER THIS AFTERNOON AND
EVENING...WITH SLIGHT CHANCES WEST AND CENTRAL OVERNIGHT.
CURRENTLY...UPPER LEVEL PATTERN UNCHANGED FROM 24 HOURS
AGO...WITH UPPER LEVEL LOW PRESSURE SYSTEMS OVER THE NORTHERN
GREAT LAKES AND DESERT SOUTHWEST REGIONS...WITH A RIDGE EXTENDING
FROM THE GULF OF MEXICO NORTHWEST ACROSS THE NORTHERN HIGH PLAINS.
SURFACE HIGH PRESSURE QUASI-STATIONARY ACROSS THE EASTERN DAKOTAS
AND UPPER MISSISSIPPI VALLEY. AREA OF SCT-BKN MID LEVEL CLOUDS
DEVELOPED A FEW HOURS AGO ACROSS THE SOUTHWEST...AND CONTINUE TO
SLOWLY EXPAND NORTH AND EAST. CULPRIT IS A WEAK LLJ ACROSS WESTERN
SOUTH DAKOTA NOSING INTO OUR LOCAL AREA. A FEW LIGHT RADAR ECHOS
HAVE MATERIALIZED ACROSS THE FAR SOUTH CENTRAL AROUND SIOUX
COUNTY. SINCE INSTABILITY PARAMETERS ARE NIL...WILL ADD AN
ISOLATED SHOWER ACROSS THE SOUTH THIS MORNING...SIMILAR TO THE
LATEST HRRR. WILL NEED TO KEEP AN EYE ON RADAR IN CASE COVERAGE
BECOMES GREATER.
UPPER LEVEL PATTERN REMAINS VIRTUALLY UNCHANGED FOR TODAY AND
TONIGHT. MAIN DIFFERENCE IS IN THE LOW TO MID LEVELS AS RETURN
FLOW RAMPS UP TODAY BRINGING MOISTURE ADVECTION INTO THE NORTHERN
PLAINS...HELPING TO INCREASE INSTABILITY ACROSS THE WESTERN THIRD
OF THE STATE. BUFFER DATA SUGGESTS MID LEVEL CAPPING FOR MUCH OF
THE AFTERNOON AT KISN-KDIK...SO SCALED BACK ON CONVECTION UNTIL
22Z WHEN A SUBTLE MID LEVEL WAVE IS PROJECTED TO RIDE OVER THE
RIDGE AXIS ACROSS CENTRAL MONTANA AND APPROACH MY WESTERN
COUNTIES. NOT SURE IF THIS WILL BE ENOUGH TO TRIGGER ANYTHING SO
KEPT POPS ON THE LOW SIDE AND CONFINED TO THE SOUTHWEST THROUGH
THE EVENING.
WEAK LOW LEVEL JET REDEVELOPS OVER THE WESTERN AND CENTRAL DAKOTAS
OVERNIGHT ALONG WITH ELEVATED INSTABILITY EXPANDING EAST ACROSS
CENTRAL NORTH DAKOTA. COMBINED WITH POSSIBLE EMBEDDED ENERGY
ROUNDING THE RIDGE...OPTED TO MAINTAIN SLIGHT CHANCES FOR T-STORMS
ACROSS MUCH OF THE WEST AND CENTRAL. REMOVED ACROSS THE EAST WHERE
STABLE AIR IS NO ADVERTISED.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 359 AM CDT THU MAY 22 2014
A WARM BUT CONVECTIVE LY ACTIVE MEMORIAL DAY WEEKEND WILL HIGHLIGHT
THE EXTENDED FORECAST.
GIVEN GOOD AGREEMENT AMONGST THE 00 UTC GUIDANCE SUITE...WILL
FOLLOW A BLEND FOR MOST FIELDS. LOW LEVEL MOISTURE WILL CONTINUE
TO INCREASE ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH SOUTHERLY
FLOW AHEAD OF A LEE SURFACE TROUGH FRIDAY AND SATURDAY. THE FIRST
ROUND OF SCATTERED THUNDERSTORMS IS POSSIBLE FRIDAY AFTERNOON AND
EVENING AS IMPULSES EJECTING OUT OF THE DESERT SOUTHWEST LOW
PROPAGATE ALONG THE UPPER LEVEL RIDGE INTO THE NORTHERN PLAINS.
1200-1700 J/KG OF ML CAPE IS FORECAST...HOWEVER...DEEP LAYER SHEAR
WILL BE MINIMAL FOR ORGANIZED CONVECTION...ON THE ORDER OF 15-20
KTS IN THE 0-6 KM LAYER. THUS THE THREAT FOR SEVERE WEATHER IS
RATHER LOW. THUNDERSTORM CHANCES INCREASE THROUGH THE DAY ON
SATURDAY AND CONTINUE SATURDAY NIGHT AND MUCH OF SUNDAY AS SURFACE
DEWPOINTS ARE FORECAST TO BE SOLIDLY IN THE 60S F WITH AN
INCREASING INFLUENCE OF A STRONGER NORTHERN STREAM WAVE AS THE
UPPER LEVEL RIDGE AXIS PROPAGATES DOWN STEAM OF WESTERN AND CENTRAL
NORTH DAKOTA. DEEP LAYER SHEAR STILL REMAINS BELOW FAVORED VALUES
FOR ORGANIZED CONVECTION SATURDAY...WITH THE BEST CHANCE OF SEVERE
THUNDERSTORMS POSSIBLY SUNDAY CENTRAL AS SHEAR INCREASES AS THE
SURFACE TROUGH PROPAGATES EAST THROUGH THE DAY. MEMORIAL DAY
MONDAY LOOKS DRY FOR MOST AREAS UNTIL THE NEXT WAVE EMBEDDED IN
FAST SOUTHWEST FLOW ALOFT IS FORECAST TO ARRIVE TOWARDS EVENING.
THE PATTERN OF ABOVE NORMAL TEMPERATURES AND DAILY CHANCES FOR
THUNDERSTORMS CONTINUES INTO MID WEEK WITH SOUTHWEST FLOW ALOFT
UPSTREAM OF THE UPPER LEVEL RIDGE AXIS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1009 AM CDT THU MAY 22 2014
VFR CONDITIONS ARE FORECAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA FOR THE 18 UTC TAF PERIOD. KEPT A VCTS TO KDIK FOR LATE
THIS AFTERNOON AND INTO EARLY THIS EVENING WITH ISOLATED TO
SCATTERED THUNDERSTORMS POSSIBLE ACROSS SOUTHWEST NORTH DAKOTA.
LATEST RAP IS SHOWING ACTIVITY POSSIBLE OVER THE SOUTH CENTRAL
THIS EVENING AS WELL. MIGHT ADD A VCTS INTO THE KBIS TAF ALSO.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...AYD
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
351 PM EDT THU MAY 22 2014
.SYNOPSIS...
A TROUGH WILL PUSH SOUTH TOWARDS LAKE ERIE OVERNIGHT THEN WEAKEN ON
FRIDAY AS HIGH PRESSURE BUILDS OVER THE CENTRAL GREAT LAKES. THE
HIGH WILL SLOWLY MOVE EAST ACROSS THE REGION THROUGH SUNDAY. AN AREA
OF LOW PRESSURE WILL PULL A COLD FRONT THROUGH THE UPPER GREAT LAKES
ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AN AREA OF LOW LEVEL MOISTURE CAN BE SEEN ON VISIBLE SATELLITE
SPILLING SOUTHEAST ACROSS LAKE ERIE OUT OF ONTARIO. THIS IS LEADING
TO SOME ENHANCEMENT OF THE CU FIELD ACROSS EXTREME NE OH/NW PA.
THERE IS ALSO SOME CIRRUS SPREADING IN FROM THE WEST AROUND THE
RIDGE. THE HIGH CLOUD SHOULD SHIFT TO THE SOUTH THIS EVENING AS THE
UPPER LEVEL TROUGH LOCATED NORTH OF LAKE SUPERIOR PIVOTS SOUTHEAST
TOWARDS LAKE ERIE OVERNIGHT. COLD ADVECTION WILL CONTINUE IN THE LOW
LEVELS WITH A 3-4C COLD POCKET SLIDING SOUTHEAST TO NEAR ERIE PA
BY 12Z FRIDAY. EXPECTING TO SEE A PERIOD OF MOSTLY CLEAR SKIES
EARLY THIS EVENING AS WE LOSE SOME OF THE DIURNAL CLOUD THEN
INCREASING OVERNIGHT WITH THE APPROACHING TROUGH. MODEL QPF AND
SOUNDING BOTH IN SUPPORT OF ENOUGH LOW LEVEL MOISTURE FOR A FEW
SPRINKLES OR EVEN AN ISOLATED SHOWER POSSIBLE IN AN ARC FROM
CLE/CAK/YNG WITH THE CONTINUED COLD ADVECTION OVERNIGHT SO
INCLUDED AN ISOLATED SHOWER IN A FEW AREAS. LOWS WILL BE
CONSIDERABLY COOLER TONIGHT AS TEMPERATURES DIP INTO THE UPPER 40S
TO NEAR 50 DEGREES.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY NIGHT/...
SKIES WILL BE PARTLY TO MOSTLY CLOUDY(EAST) INTO THE AFTERNOON ON
FRIDAY WITH STEEP LOW LEVEL LAPSE RATES IN PLACE. THE TROUGH IN THE
EAST WILL RELAX THROUGH THE DAY WITH HIGH PRESSURE BUILDING OVER THE
WESTERN LAKES REGION. HIGH TEMPERATURES WILL BE JUST A FEW DEGREES
COOLER THAN TODAY AND MAY NOT ESCAPE THE 50S IN NW PA IF CLOUD ARE
THICK ENOUGH.
THIS AREA OF HIGH PRESSURE WILL BUILD EAST ACROSS THE
REGION BRINGING DRY CONDITIONS THROUGH AT LEAST SUNDAY. DESPITE SOME
LINGERING CU ON SATURDAY...THERE WILL BE A LOT OF SUN OVER THE
WEEKEND WITH GOOD INSULATION. THE PREVAILING NORTHERLY FLOW WILL
WEAKEN GIVING WAY TO JUST AFTERNOON LAKE BREEZES RESULTING IN A
GRADUAL WARM UP. HIGHS WILL RECOVER INTO THE LOW 70S BY SATURDAY AND
MID 70S TO UPPER 70S ON SUNDAY. AREAS CLOSER TO LAKE ERIE WILL
REMAIN A FEW DEGREES COOLER.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
THOUGH RAIN CHANCES RETURN LATER IN THE FORECAST THE COVERAGE AND
AMOUNTS EXPECTED SUPPORT AN IMPROVEMENT IN THE SATURATED GROUND
CONDITIONS OF THE LAST FEW WEEKS. FOR MEMORIAL DAY MODELS TRY TO
BRING RAIN TO THE WESTERN COUNTIES LATE. WITH RIDGING ALOFT AND
UPPER LEVEL SHORT WAVE WELL TO THE WEST IT MAY TAKE SOME TIME TO
MATERIALIZE. KEPT CHANCES MINIMAL FOR THE DAY...WITH INCREASING
CHANCES OVERNIGHT INTO TUESDAY. THE LOW PRESSURE SYSTEM WILL MOVE
EAST TUESDAY FOLLOWED ONCE AGAIN BY HIGH PRESSURE. TEMPERATURES WILL
RANGE ON THE WARMER SIDE OF GUIDANCE WITH HIGHS IN THE 80S MONDAY
AND TUESDAY...FALLING TO THE 70S MID TO LAKE WEEK. THE HIGHER DEW
POINTS WILL REMAIN FURTHER SOUTH.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
BEGINNING TO SEE AFTERNOON CU DEVELOP STARTING AROUND 3500`
INCREASING TO AROUND 4500` THROUGH THE AFTERNOON. MOST AREAS WILL
CLEAR OUT WITH LACK OF DIURNAL HEATER...BUT CLOUDS WRAPPING AROUND
THE MIDLEVEL LOW COULD TRACK IN OVER THE ERIE TERMINAL THIS EVENING.
ADDITIONAL MOISTURE WILL MOVE IN TO THE AREA LATE TONIGHT AND EARLY
FRIDAY. MODELS DISAGREEING ON THE AMOUNT OF MOISTURE WITH SOME
SHOWING A BROKEN 5K` DECK WHICH THE RUC SHOWS SCATTERED AT BEST. THE
MOST LIKELY TERMINALS TO SEE THE LOWER CLOUD REDEVELOPMENT WILL
BE THOSE IN THE EAST CLOSER TO THE LOW LIKE YNG/CAK/ERI AND PERHAPS
EVEN CLE. HIGH PRESSURE IS BUILDING IN FROM THE WEST AND SUBSIDENCE
WILL MAKE SUPPORT LESS CLOUDS IN OVER FDY/TOL/MFD.
.OUTLOOK...VFR.
&&
.MARINE...
THE NORTHWESTERLY FLOW WILL BE PREDOMINANT THE NEXT FEW DAYS WITH
SPEEDS 15KT OR LESS. HIGH PRESSURE WILL LINGER OVER THE GREAT LAKES
FOR THE WEEKEND WITH A FRONTAL PASSAGE LATE MONDAY INTO TUESDAY.
WEATHER WILL REMAIN QUIET OVER THE WATERS THROUGH THE FORECAST.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...JAMISON
AVIATION...JAMISON
MARINE...JAMISON
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
116 PM EDT THU MAY 22 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH ACROSS THE FORECAST AREA THIS MORNING. LARGE
AREA OF CANADIAN HIGH PRESSURE WILL MOVE SOUTHEAST ACROSS THE GREAT
LAKES...THEN MOVE OFF THE SOUTHEAST COAST LATE SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SKIES HAVE BECOME MOSTLY SUNNY WITH INCREASING SUBSIDENCE BEHIND
THE FRONT THIS MORNING WITH THE ONLY EXCEPTION BEING IN NW PA
WHERE STRATUS CONTINUES TO ERODE. DIURNAL CU IS STARTING TO FILL
IN ACROSS NW OHIO WITH AN AREA OF CLOUDS/HIGHER MOISTURE APPROACHING THE
NORTH SIDE OF LAKE ERIE. THIS WILL RESULT IN SOME INCREASE IN
CU AS WE HEAD TOWARDS LATE AFTERNOON. UNTIL THEN IT LOOKS LIKE
TEMPERATURES FROM CAK-YNG ARE RUNNING A COUPLE DEGREES HIGHER THAN
FORECAST AND NUDGED HIGHS UP A DEGREE OR TWO.
ORIGINAL DISCUSSION... CONVECTION HAS MOVED SOUTH OF THE FORECAST
AREA...THINK THE REMAINDER OF THE DAY SHOULD REMAIN DRY...ALTHOUGH
NOT OUT OF THE QUESTION THAT A STRAY SHRA/TSRA COULD POP UP NEAR
THE FRONTAL BOUNDARY TOWARD DAYBREAK. THE COLD FRONT NOW THROUGH
NORTHWEST OHIO AND ALL MODELS FORECAST IT TO MOVE SOUTH OF THE
AREA BY LATE MORNING. TEMPERATURES WILL BE SLOW TO WARM WITH THE
COOLER AND DRIER AIRMASS MOVING OVER THE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AT THE SURFACE LARGE AREA OF CANADIAN HIGH PRESSURE WILL MOVE
SOUTHEAST ACROSS THE GREAT LAKES THIS WEEKEND PROVIDING DRIER AND
COOLER CONDITIONS. LOW SHOULD BE CENTERED OVER THE AREA BY
SATURDAY EVENING. THAT SAID AT THE UPPER LEVELS A TROUGH WILL SWING
ACROSS EASTERN LAKE ERIE LATE TONIGHT. LEFT CHANCE POPS GOING FOR
EXTREME NE OH AND NW PA.
THE 850 MB TEMPERATURES ARE EXPECTED TO DIP TO AROUND PLUS 4 C BY
FRIDAY MORNING. WITH THE LAKE TEMPERATURE IN THE MID TO UPPER 50S
THAT WILL BE COLD ENOUGH FOR SOME LAKE EFFECT CLOUDS EXTREME NE OH
AND NW PA. EVEN THOUGH THE SURFACE WINDS DO TURN TO THE WEST
FRIDAY...THE UPPER LEVEL FLOW REMAINS FROM THE NW. WILL SEE A
GRADUAL WARMING TREND STARTING SUNDAY AS SURFACE HIGH MOVES EAST OF
THE AREA SETTING UP A SOUTHERLY FLOW.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
NOT MANY CHANCES TO THE LONG TERM TODAY. A WARM AND MOISTENING
AIRMASS WILL BE OVER THE LOCAL AREA AT THE START OF THE PERIOD.
WESTERN AREAS COULD SEE A FEW THUNDERSTORMS BY LATE MONDAY BUT
BETTER CHANCES FOR STORMS WILL COME ON MONDAY NIGHT AND TUESDAY.
THIS ACTIVITY WILL COME IN RESPONSE TO A WEAK LOW PASSING JUST TO
THE NORTH OF THE AREA. BOTH THE LATEST GFS AND ECMWF SHOW THIS
SYSTEM. IT APPEARS EVEN BETTER CHANCES FOR PRECIP WILL BE JUST
NORTH OF THE AREA. HIGH PRESSURE WILL RETURN FOR WEDNESDAY AND WILL
TRY FOR DRY WEATHER. HIGHS MONDAY AND TUESDAY WILL BE AT LEAST 10
DEGREES ABOVE NORMAL WITH SLIGHTLY COOLER READINGS EXPECTED ON
WEDNESDAY.
&&
.AVIATION /18Z THURSDAY THROUGH MONDAY/...
BEGINNING TO SEE AFTERNOON CU DEVELOP STARTING AROUND 3500`
INCREASING TO AROUND 4500` THROUGH THE AFTERNOON. MOST AREAS WILL
CLEAR OUT WITH LACK OF DIURNAL HEATER...BUT CLOUDS WRAPPING AROUND
THE MIDLEVEL LOW COULD TRACK IN OVER THE ERIE TERMINAL THIS EVENING.
ADDITIONAL MOISTURE WILL MOVE IN TO THE AREA LATE TONIGHT AND EARLY
FRIDAY. MODELS DISAGREEING ON THE AMOUNT OF MOISTURE WITH SOME
SHOWING A BROKEN 5K` DECK WHICH THE RUC SHOWS SCATTERED AT BEST. THE
MOST LIKELY TERMINALS TO SEE THE LOWER CLOUD REDEVELOPMENT WILL
BE THOSE IN THE EAST CLOSER TO THE LOW LIKE YNG/CAK/ERI AND PERHAPS
EVEN CLE. HIGH PRESSURE IS BUILDING IN FROM THE WEST AND SUBSIDENCE
WILL MAKE SUPPORT LESS CLOUDS IN OVER FDY/TOL/MFD.
.OUTLOOK...VFR.
&&
.MARINE...
A COLD FRONT WILL PUSH EAST OF THE LAKE THIS MORNING. W TO NW FLOW
IS EXPECTED BEHIND THE FRONT. DO NOT THINK WINDS OR WAVES WILL GET
HIGH ENOUGH FOR SMALL CRAFT HEADLINES. THE DAY CREW CAN TAKE A
CLOSER LOOK. HIGH PRESSURE WILL BUILD IN FOR THE WEEKEND WITH
MAINLY LIGHT FLOW. THE SURFACE RIDGE WILL PUSH EAST OF THE LAKE BY
LATE SUNDAY WHICH WILL ALLOW SW FLOW TO RETURN. SW FLOW WILL THEN
CONTINUE ON MONDAY. OUTSIDE OF A FEW HOURS THIS MORNING...WINDS THE
ENTIRE PERIOD SHOULD BE UNDER 15 KNOTS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB
SHORT TERM...DJB/KEC
LONG TERM...KUBINA
AVIATION...SJAMISON
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS NORMAN OK
1248 PM CDT THU MAY 22 2014
.DISCUSSION...
REFER TO THE 18Z AVIATION FORECAST BELOW...
&&
.AVIATION...
EXPECT MOST OF THE CONVECTION ACROSS CENTRAL KANSAS WILL
REMAIN NORTH OF OKLAHOMA. HOWEVER...THE HRRR DEVELOPS
WIDELY SCATTERED CONVECTION THIS AFTERNOON ACROSS NORTHWEST
OKLAHOMA.
STORMS HAVE ALREADY FORMED IN EASTERN NEW MEXICO THIS AFTERNOON
AND ADDITIONAL STORMS SHOULD FORM FARTHER EAST. SOME OF THIS
ACTIVITY MAY MOVE INTO FAR NORTHWEST OKLAHOMA DURING THE MID
TO LATE EVENING. OTHER SHOWERS MAY MOVE INTO FAR WESTERN OKLAHOMA
DURING THE OVERNIGHT/EARLY MORNING.
MAINLY VFR CONDITIONS AND SOUTH WINDS WILL PREVAIL THROUGH
THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1029 AM CDT THU MAY 22 2014/
UPDATE...
OVERALL FORECAST LOOKS PRETTY GOOD... JUST SOME MINOR TWEEKS TO
SHOW CURRENT TRENDS. A FEW SHOWERS/STORMS WILL BE POSSIBLE IN NW
PARTS OF THE FA THROUGH THE AFTERNOON HOURS. TEMPERATURES EXPECTED
TO REACH THE 80S AND LOW 90S THIS AFTERNOON.
MAXWELL
PREV DISCUSSION... /ISSUED 624 AM CDT THU MAY 22 2014/
DISCUSSION...
REFER TO THE 12Z AVIATION FORECAST BELOW...
AVIATION...
SOUTHERLY WINDS WILL INCREASE BY LATE MORNING WITH VFR CIGS
BUILDING INTO PORTIONS OF SOUTHWESTERN AND CENTRAL OKLAHOMA
THROUGH THE AFTERNOON. ISOLD TSRA WILL BUILD OVER THE TX
PANHANDLE...AND MAY AFFECT NORTHWESTERN TERMINALS FROM 00Z ONWARD.
FOR NOW...WILL MENTION VCTS AT KGAG...WHERE CONFIDENCE IS SOMEWHAT
HIGHER IN TSRA THIS EVENING.
PREV DISCUSSION... /ISSUED 329 AM CDT THU MAY 22 2014/
DISCUSSION...
THINKING HAS CHANGED VERY LITTLE REGARDING THE FORECAST THROUGH
THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK. CURRENTLY...A LARGE
CLOSED LOW CONTINUES TO DRIFT EASTWARD OVER THE SOUTHWEST U.S.
THIS FEATURE WILL SLOWLY BUT SURELY HEAD INTO THE SOUTHERN/CENTRAL
PLAINS REGION OVER THE WEEKEND. BEFORE THAT HAPPENS THOUGH...WE DO
EXPECT AT LEAST ONE MORE WARM DRY DAY OVER THE MAJORITY OF
OKLAHOMA AND NORTH TEXAS. WHILE TEMPERATURES WILL BE NOWHERE NEAR
AS WARM AS YESTERDAY OR THE DAY BEFORE...EXPECT MOST AREAS TO
REACH THE UPPER 80S TO LOW 90S...WHICH COMBINED WITH RELATIVELY
HIGH MOISTURE CONTENT WILL MAKE FOR A RATHER MUGGY THURSDAY.
WHILE A SLIM CHANCE OF SHOWERS/STORMS WILL EXIST TONIGHT...THE
RAIN CHANCES WILL REALLY START TO INCREASE FRIDAY. AS THE UPPER
LOW MEANDERS EASTWARD...AN UPPER DIFFLUENT PATTERN WITHIN LARGE
SCALE SWRLY MID LEVEL FLOW WILL OVERSPREAD THE SOUTHERN
PLAINS...PROMOTING SCATTERED TO NUMEROUS STORMS EACH DAY FROM
FRIDAY THROUGH MONDAY. WITH RATHER WEAK CAPPING...STORMS WILL
INITIATE FAIRLY EARLY EACH DAY AND LINGER INTO THE EVENING BEFORE
DISSIPATING OR WEAKENING OVERNIGHT. ADEQUATE MOISTURE AND MODEST
INSTABILITY MAY YIELD SOME ISOLATED SEVERE WEATHER POTENTIAL
SATURDAY THROUGH MONDAY...MAINLY IN THE FORM OF HAIL AND STRONG
WINDS...BUT WIDESPREAD SEVERE WEATHER APPEARS VERY UNLIKELY WITH
THIS SYSTEM. ONE THING THAT DOES SEEM PROBABLE IS A GOOD AMOUNT OF
RAIN OVER AREAS THAT REALLY NEED IT. WIDESPREAD ONE INCH PLUS
RAINFALL TOTALS SEEM REASONABLE FROM FRIDAY THROUGH EARLY NEXT
WEEK...THOUGH A FEW LOCATIONS MAY SEE 4 INCHES OR MORE OF RAIN
WHEN ALL IS SAID AND DONE.
BY MID TO LATE NEXT WEEK...CONSIDERABLE DISAGREEMENT EXISTS AMONG
LONG RANGE MODELS...THOUGH RAIN CHANCES SHOULD GENERALLY DECREASE
AS THE UPPER LOW DRIFTS INTO THE MISSISSIPPI VALLEY...INDUCING
WEAK NORTHWESTERLY MID LEVEL FLOW ACROSS THE REGION. WEAK/FLAT
RIDING SHOULD ATTEMPT TO BUILD BACK INTO THE SOUTHERN
STATES...ALLOWING FOR THE RETURN OF WARM AND MUGGY CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 84 67 85 / 0 40 40 30
HOBART OK 69 83 66 84 / 20 50 40 40
WICHITA FALLS TX 70 85 67 86 / 10 40 30 40
GAGE OK 66 81 63 81 / 40 50 60 40
PONCA CITY OK 68 86 67 86 / 20 40 50 30
DURANT OK 69 87 68 86 / 0 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1145 PM EDT FRI MAY 23 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH ON SATURDAY...TRIGGERING
ANOTHER ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN
THE AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD
OVER THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS
LIKELY TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 9 AM SATURDAY MORNING/...
10 PM UPDATE...
ALMOST ALL RADAR RETURNS GONE. BUT THE LOW CLOUDS ARE GETTING
FARTHER INTO THE AREA AND LOOK LIKE THEY MEAN BUSINESS. WILL JACK
UP THE CLOUDS FOR THE NEXT FEW HOURS OVER THE NW HALF OF THE AREA.
AGAIN...GOING MINS LOOK FINE WITH JUST A FEW MORE DEGS OF FALL IN
THE CLOUDY AREAS AND 7-8F IN THE MORE-CLEAR AREAS. SOME DZ OUT OF
THE LOW DECK IS POSSIBLE NEAR THE NY BORDER AND PERHAPS IN THE
LIFT OF THE LAURELS. 300FT CEILING AND LIGHT FOG AT BFD...BUT
WILL HOLD OFF ON MENTIONING DZ FOR THE BULK OF THE NIGHT. JUST
KEPT A MENTION OF ISOLD SHRA EARLY.
7 PM UPDATE...
JUST A LITTLE LIGHTNING THIS AFTN...AND IT IS ALL OFF TO THE EAST.
SHRA LINGERING IN THE POCONOS/LOWER SUSQ WILL DISSIPATE SHORTLY.
RUC/RAP AND HRRR BOTH DWINDLE THE PATCH OF SHOWERS OVER BUF AS
WELL. SO...WILL TAPER POPS OFF OVER THE NEXT 2-3 HRS. BUT UPSLOPE
AND CYCLONIC FLOW WILL KEEP QUITE A BIT OF CLOUDS OVER THE NWRN
MTS FOR AT LEAST THE FIRST HALF OF THE NIGHT. ALL MDL SOLUTIONS
KEEP RH HIGH IN THE 925-850MB LAYER. SO THIS MEANS IT COULD STAY
PRETTY CLOUDY TO THE N/W OF UNV...AND PROBABLY HAMPER THE VIEWING
OF THE METEOR SHOWER OVERNIGHT IN THOSE LOCATIONS. TEMPS MAY ALSO
BE HELD UP A DEG OR TWO DUE TO THE CLOUDS. HAVE KEPT THESE NUMBERS
AS IS.
PREV...
MID AFTERNOON VISIBLE AND WATER VAPOR LOOP SHOWS A POTENT MID-
UPPER LEVEL SHORTWAVE MOVING SE INTO THE NRN MTNS OF PENN.
AN EXTENSIVE DECK OF MDT CU AND STRATO CU HAS FORMED/SPREAD SE
ACROSS THE REGION IN RESPONSE TO 2-3C OF MID/UPPER LEVEL COOLING
OVER THE PAST 4-6 HOURS /ASSOCIATED WITH THE APPROACH OF THE
SHORTWAVE/.
EXPECT GRADUALLY INCREASING COVERAGE OF SHOWERS TO DEVELOP/ADVECT
SOUTH INTO THE CWA THROUGH 22Z...BEFORE GRADUALLY DIMINISHING
THROUGH EARLY THIS EVENING.
EMBEDDED LOW-TOPPED CBS ARE POSSIBLE BETWEEN 18Z-00Z /ALONG WITH
BRIEF HEAVY RAIN AND ISOLATED INSTANCES OF PEA-SIZE HAIL/ ACROSS
THE NCENT MTNS AND MID SUSQ VALLEY WHERE THE COOLEST TEMPS ALOFT
AND STEEPEST MID-LEVEL LAPSE RATES OF NEARLY 6.5C/KM /AND SFC
BASED CAPES OF SVRL HUNDRED J/KG WILL BE FOUND.
TEMPS ARE CLOSE TO THEIR MAX VALUES ATTM...RANGING FROM THE M-U50S
OVR THE NW MTNS...TO THE L70S ACROSS THE LOWER AND MID SUSQ
VALLEY. LOCATIONS SEEING MORE NUMEROUS /OR HEAVIER/ SHOWERS LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL SEE A QUICK 5-8F TEMP
DROP GIVEN THE 15-20F T/TD SPREAD.
THE SHOWERS WILL STEADILY DIMINISH AND DRIFT EAST OF THE REGION
THIS EVENING AS THE UPPER SHORTWAVE ROTATES SEWD AND OFF THE MID
ATLANTIC COAST. SKY COVER SHOULD BECOME SCT ACROSS THE SCENT
COUNTIES AND SUSQ VALLEY AROUND OR SHORTLY AFTER 04Z.
PATCHY FOG IS POSSIBLE LATE TONIGHT /ESPECIALLY IN THE DEEPER NRN
VALLEYS WHERE WET GROUND FROM THE EVENING SHOWERS WILL COMBINE
WILL HELP TO GREATLY NARROW THE T/TD SPREAD UNDER PARTIAL CLEARING
SKIES WITH DIMINISHING WIND.
LOW TEMPS AROUND SUNRISE SATURDAY WILL VARY FROM THE MID 40S
ACROSS THE NRN AND WRN MTNS...TO AROUND 50F IN THE LOWER SUSQ
VALLEY.
&&
.SHORT TERM /9 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIAN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIGHEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERATURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS CONTINUE TO FILL IN OVERNIGHT AS COLD AIR STREAMS OVER THE
NW MTNS AND THE LAURELS. MIXING CONTINUES THROUGH MOST OF CENTRAL
AND SOUTHWEST PA...THIS HAS ALLOWED FOR GUSTY WINDS TO CONTINUE
THROUGH THE FIRST HALF OF THE EVENING. EXPECT THAT THESE WINDS
SHOULD SUBSIDE AS THE REGION DECOUPLES BY 06Z. MVFR AND LOWER
CIGS HAVE OCCURRED AT JST...WITH LIFR CIGS AND VSBYS AT BFD. THSE
CONDITIONS AT BFD SHOULD CONTINUE OVERNIGHT UNTIL THEY BEGIN TO
LIFT AROUND 12Z...TO MVFR AND THEN TO VFR BY 15Z. JST SHOULD LOWER
OVERNIGHT TO IFR BEFORE LIFTING BY 12Z.
SATURDAY WILL AGAIN FEATURE SOME PATCHY LOW CLOUDS AND FOG EARLY
FOLLOWED BY PARTLY TO MOSTLY SUNNY SKIES DURING THE MID TO LATE
MORNING...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING IN THE
AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.SUN...AM FOG POSSIBLE...OTHERWISE VFR.
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1016 PM EDT FRI MAY 23 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH ON SATURDAY...TRIGGERING
ANOTHER ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN
THE AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD
OVER THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS
LIKELY TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 9 AM SATURDAY MORNING/...
10 PM UPDATE...
ALMOST ALL RADAR RETURNS GONE. BUT THE LOW CLOUDS ARE GETTING
FARTHER INTO THE AREA AND LOOK LIKE THEY MEAN BUSINESS. WILL JACK
UP THE CLOUDS FOR THE NEXT FEW HOURS OVER THE NW HALF OF THE AREA.
AGAIN...GOING MINS LOOK FINE WITH JUST A FEW MORE DEGS OF FALL IN
THE CLOUDY AREAS AND 7-8F IN THE MORE-CLEAR AREAS. SOME DZ OUT OF
THE LOW DECK IS POSSIBLE NEAR THE NY BORDER AND PERHAPS IN THE
LIFT OF THE LAURELS. 300FT CEILING AND LIGHT FOG AT BFD...BUT
WILL HOLD OFF ON MENTIONING DZ FOR THE BULK OF THE NIGHT. JUST
KEPT A MENTION OF ISOLD SHRA EARLY.
7 PM UPDATE...
JUST A LITTLE LIGHTNING THIS AFTN...AND IT IS ALL OFF TO THE EAST.
SHRA LINGERING IN THE POCONOS/LOWER SUSQ WILL DISSIPATE SHORTLY.
RUC/RAP AND HRRR BOTH DWINDLE THE PATCH OF SHOWERS OVER BUF AS
WELL. SO...WILL TAPER POPS OFF OVER THE NEXT 2-3 HRS. BUT UPSLOPE
AND CYCLONIC FLOW WILL KEEP QUITE A BIT OF CLOUDS OVER THE NWRN
MTS FOR AT LEAST THE FIRST HALF OF THE NIGHT. ALL MDL SOLUTIONS
KEEP RH HIGH IN THE 925-850MB LAYER. SO THIS MEANS IT COULD STAY
PRETTY CLOUDY TO THE N/W OF UNV...AND PROBABLY HAMPER THE VIEWING
OF THE METEOR SHOWER OVERNIGHT IN THOSE LOCATIONS. TEMPS MAY ALSO
BE HELD UP A DEG OR TWO DUE TO THE CLOUDS. HAVE KEPT THESE NUMBERS
AS IS.
PREV...
MID AFTERNOON VISIBLE AND WATER VAPOR LOOP SHOWS A POTENT MID-
UPPER LEVEL SHORTWAVE MOVING SE INTO THE NRN MTNS OF PENN.
AN EXTENSIVE DECK OF MDT CU AND STRATO CU HAS FORMED/SPREAD SE
ACROSS THE REGION IN RESPONSE TO 2-3C OF MID/UPPER LEVEL COOLING
OVER THE PAST 4-6 HOURS /ASSOCIATED WITH THE APPROACH OF THE
SHORTWAVE/.
EXPECT GRADUALLY INCREASING COVERAGE OF SHOWERS TO DEVELOP/ADVECT
SOUTH INTO THE CWA THROUGH 22Z...BEFORE GRADUALLY DIMINISHING
THROUGH EARLY THIS EVENING.
EMBEDDED LOW-TOPPED CBS ARE POSSIBLE BETWEEN 18Z-00Z /ALONG WITH
BRIEF HEAVY RAIN AND ISOLATED INSTANCES OF PEA-SIZE HAIL/ ACROSS
THE NCENT MTNS AND MID SUSQ VALLEY WHERE THE COOLEST TEMPS ALOFT
AND STEEPEST MID-LEVEL LAPSE RATES OF NEARLY 6.5C/KM /AND SFC
BASED CAPES OF SVRL HUNDRED J/KG WILL BE FOUND.
TEMPS ARE CLOSE TO THEIR MAX VALUES ATTM...RANGING FROM THE M-U50S
OVR THE NW MTNS...TO THE L70S ACROSS THE LOWER AND MID SUSQ
VALLEY. LOCATIONS SEEING MORE NUMEROUS /OR HEAVIER/ SHOWERS LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL SEE A QUICK 5-8F TEMP
DROP GIVEN THE 15-20F T/TD SPREAD.
THE SHOWERS WILL STEADILY DIMINISH AND DRIFT EAST OF THE REGION
THIS EVENING AS THE UPPER SHORTWAVE ROTATES SEWD AND OFF THE MID
ATLANTIC COAST. SKY COVER SHOULD BECOME SCT ACROSS THE SCENT
COUNTIES AND SUSQ VALLEY AROUND OR SHORTLY AFTER 04Z.
PATCHY FOG IS POSSIBLE LATE TONIGHT /ESPECIALLY IN THE DEEPER NRN
VALLEYS WHERE WET GROUND FROM THE EVENING SHOWERS WILL COMBINE
WILL HELP TO GREATLY NARROW THE T/TD SPREAD UNDER PARTIAL CLEARING
SKIES WITH DIMINISHING WIND.
LOW TEMPS AROUND SUNRISE SATURDAY WILL VARY FROM THE MID 40S
ACROSS THE NRN AND WRN MTNS...TO AROUND 50F IN THE LOWER SUSQ
VALLEY.
&&
.SHORT TERM /9 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIAN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIGHEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERATURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS CONTINUE TO FILL IN OVERNIGHT AS COLD AIR STREAMS OVER THE
NW MTNS AND THE LAURELS. MIXING CONTINUES THROUGH MOST OF CENTRAL
AND SOUTHWEST PA...THIS HAS ALLOWED FOR GUSTY WINDS TO CONTINUE
THROUGH THE FIRST HALF OF THE EVENING. EXPECT THAT THESE WINDS
SHOULD SUBSIDE AS THE REGION DECOUPLES BY 06Z. MVFR AND LOWER
CIGS HAVE OCCURRED AT JST...WITH LIFR CIGS AND VSBYS AT BFD. THSE
CONDITIONS AT BFD SHOULD CONTINUE OVERNIGHT UNTIL THEY BEGIN TO
LIFT AROUND 12Z...TO MVFR AND THEN TO VFR BY 15Z. JST SHOULD LOWER
OVERNIGHT TO IFR BEFORE LIFTING BY 12Z.
SATURDAY WILL AGAIN FEATURE SOME PATCHY LOW CLOUDS AND FOG EARLY
FOLLOWED BY PARTLY TO MOSTLY SUNNY SKIES DURING THE MID TO LATE
MORNING...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING IN THE
AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.SUN...AM FOG POSSIBLE...OTHERWISE VFR.
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
938 PM EDT FRI MAY 23 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH ON SATURDAY...TRIGGERING
ANOTHER ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN
THE AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD
OVER THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS
LIKELY TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
7 PM UPDATE...
JUST A LITTLE LIGHTNING THIS AFTN...AND IT IS ALL OFF TO THE EAST.
SHRA LINGERING IN THE POCONOS/LOWER SUSQ WILL DISSIPATE SHORTLY.
RUC/RAP AND HRRR BOTH DWINDLE THE PATCH OF SHOWERS OVER BUF AS
WELL. SO...WILL TAPER POPS OFF OVER THE NEXT 2-3 HRS. BUT UPSLOPE
AND CYCLONIC FLOW WILL KEEP QUITE A BIT OF CLOUDS OVER THE NWRN
MTS FOR AT LEAST THE FIRST HALF OF THE NIGHT. ALL MDL SOLUTIONS
KEEP RH HIGH IN THE 925-850MB LAYER. SO THIS MEANS IT COULD STAY
PRETTY CLOUDY TO THE N/W OF UNV...AND PROBABLY HAMPER THE VIEWING
OF THE METEOR SHOWER OVERNIGHT IN THOSE LOCATIONS. TEMPS MAY ALSO
BE HELD UP A DEG OR TWO DUE TO THE CLOUDS. HAVE KEPT THESE NUMBERS
AS IS.
PREV...
MID AFTERNOON VISIBLE AND WATER VAPOR LOOP SHOWS A POTENT MID-
UPPER LEVEL SHORTWAVE MOVING SE INTO THE NRN MTNS OF PENN.
AN EXTENSIVE DECK OF MDT CU AND STRATO CU HAS FORMED/SPREAD SE
ACROSS THE REGION IN RESPONSE TO 2-3C OF MID/UPPER LEVEL COOLING
OVER THE PAST 4-6 HOURS /ASSOCIATED WITH THE APPROACH OF THE
SHORTWAVE/.
EXPECT GRADUALLY INCREASING COVERAGE OF SHOWERS TO DEVELOP/ADVECT
SOUTH INTO THE CWA THROUGH 22Z...BEFORE GRADUALLY DIMINISHING
THROUGH EARLY THIS EVENING.
EMBEDDED LOW-TOPPED CBS ARE POSSIBLE BETWEEN 18Z-00Z /ALONG WITH
BRIEF HEAVY RAIN AND ISOLATED INSTANCES OF PEA-SIZE HAIL/ ACROSS
THE NCENT MTNS AND MID SUSQ VALLEY WHERE THE COOLEST TEMPS ALOFT
AND STEEPEST MID-LEVEL LAPSE RATES OF NEARLY 6.5C/KM /AND SFC
BASED CAPES OF SVRL HUNDRED J/KG WILL BE FOUND.
TEMPS ARE CLOSE TO THEIR MAX VALUES ATTM...RANGING FROM THE M-U50S
OVR THE NW MTNS...TO THE L70S ACROSS THE LOWER AND MID SUSQ
VALLEY. LOCATIONS SEEING MORE NUMEROUS /OR HEAVIER/ SHOWERS LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL SEE A QUICK 5-8F TEMP
DROP GIVEN THE 15-20F T/TD SPREAD.
THE SHOWERS WILL STEADILY DIMINISH AND DRIFT EAST OF THE REGION
THIS EVENING AS THE UPPER SHORTWAVE ROTATES SEWD AND OFF THE MID
ATLANTIC COAST. SKY COVER SHOULD BECOME SCT ACROSS THE SCENT
COUNTIES AND SUSQ VALLEY AROUND OR SHORTLY AFTER 04Z.
PATCHY FOG IS POSSIBLE LATE TONIGHT /ESPECIALLY IN THE DEEPER NRN
VALLEYS WHERE WET GROUND FROM THE EVENING SHOWERS WILL COMBINE
WILL HELP TO GREATLY NARROW THE T/TD SPREAD UNDER PARTIAL CLEARING
SKIES WITH DIMINISHING WIND.
LOW TEMPS AROUND SUNRISE SATURDAY WILL VARY FROM THE MID 40S
ACROSS THE NRN AND WRN MTNS...TO AROUND 50F IN THE LOWER SUSQ
VALLEY.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIAN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIGHEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERATURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS CONTINUE TO FILL IN OVERNIGHT AS COLD AIR STREAMS OVER THE
NW MTNS AND THE LAURELS. MIXING CONTINUES THROUGH MOST OF CENTRAL
AND SOUTHWEST PA...THIS HAS ALLOWED FOR GUSTY WINDS TO CONTINUE
THROUGH THE FIRST HALF OF THE EVENING. EXPECT THAT THESE WINDS
SHOULD SUBSIDE AS THE REGION DECOUPLES BY 06Z. MVFR AND LOWER
CIGS HAVE OCCURRED AT JST...WITH LIFR CIGS AND VSBYS AT BFD. THSE
CONDITIONS AT BFD SHOULD CONTINUE OVERNIGHT UNTIL THEY BEGIN TO
LIFT AROUND 12Z...TO MVFR AND THEN TO VFR BY 15Z. JST SHOULD LOWER
OVERNIGHT TO IFR BEFORE LIFTING BY 12Z.
SATURDAY WILL AGAIN FEATURE SOME PATCHY LOW CLOUDS AND FOG EARLY
FOLLOWED BY PARTLY TO MOSTLY SUNNY SKIES DURING THE MID TO LATE
MORNING...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING IN THE
AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.SUN...AM FOG POSSIBLE...OTHERWISE VFR.
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
703 PM EDT FRI MAY 23 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH ON SATURDAY...TRIGGERING
ANOTHER ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN
THE AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD
OVER THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS
LIKELY TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
7 PM UPDATE...
JUST A LITTLE LIGHTNING THIS AFTN...AND IT IS ALL OFF TO THE EAST.
SHRA LINGERING IN THE POCONOS/LOWER SUSQ WILL DISSIPATE SHORTLY.
RUC/RAP AND HRRR BOTH DWINDLE THE PATCH OF SHOWERS OVER BUF AS
WELL. SO...WILL TAPER POPS OFF OVER THE NEXT 2-3 HRS. BUT UPSLOPE
AND CYCLONIC FLOW WILL KEEP QUITE A BIT OF CLOUDS OVER THE NWRN
MTS FOR AT LEAST THE FIRST HALF OF THE NIGHT. ALL MDL SOLUTIONS
KEEP RH HIGH IN THE 925-850MB LAYER. SO THIS MEANS IT COULD STAY
PRETTY CLOUDY TO THE N/W OF UNV...AND PROBABLY HAMPER THE VIEWING
OF THE METEOR SHOWER OVERNIGHT IN THOSE LOCATIONS. TEMPS MAY ALSO
BE HELD UP A DEG OR TWO DUE TO THE CLOUDS. HAVE KEPT THESE NUMBERS
AS IS.
PREV...
MID AFTERNOON VISIBLE AND WATER VAPOR LOOP SHOWS A POTENT MID-
UPPER LEVEL SHORTWAVE MOVING SE INTO THE NRN MTNS OF PENN.
AN EXTENSIVE DECK OF MDT CU AND STRATO CU HAS FORMED/SPREAD SE
ACROSS THE REGION IN RESPONSE TO 2-3C OF MID/UPPER LEVEL COOLING
OVER THE PAST 4-6 HOURS /ASSOCIATED WITH THE APPROACH OF THE
SHORTWAVE/.
EXPECT GRADUALLY INCREASING COVERAGE OF SHOWERS TO DEVELOP/ADVECT
SOUTH INTO THE CWA THROUGH 22Z...BEFORE GRADUALLY DIMINISHING
THROUGH EARLY THIS EVENING.
EMBEDDED LOW-TOPPED CBS ARE POSSIBLE BETWEEN 18Z-00Z /ALONG WITH
BRIEF HEAVY RAIN AND ISOLATED INSTANCES OF PEA-SIZE HAIL/ ACROSS
THE NCENT MTNS AND MID SUSQ VALLEY WHERE THE COOLEST TEMPS ALOFT
AND STEEPEST MID-LEVEL LAPSE RATES OF NEARLY 6.5C/KM /AND SFC
BASED CAPES OF SVRL HUNDRED J/KG WILL BE FOUND.
TEMPS ARE CLOSE TO THEIR MAX VALUES ATTM...RANGING FROM THE M-U50S
OVR THE NW MTNS...TO THE L70S ACROSS THE LOWER AND MID SUSQ
VALLEY. LOCATIONS SEEING MORE NUMEROUS /OR HEAVIER/ SHOWERS LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL SEE A QUICK 5-8F TEMP
DROP GIVEN THE 15-20F T/TD SPREAD.
THE SHOWERS WILL STEADILY DIMINISH AND DRIFT EAST OF THE REGION
THIS EVENING AS THE UPPER SHORTWAVE ROTATES SEWD AND OFF THE MID
ATLANTIC COAST. SKY COVER SHOULD BECOME SCT ACROSS THE SCENT
COUNTIES AND SUSQ VALLEY AROUND OR SHORTLY AFTER 04Z.
PATCHY FOG IS POSSIBLE LATE TONIGHT /ESPECIALLY IN THE DEEPER NRN
VALLEYS WHERE WET GROUND FROM THE EVENING SHOWERS WILL COMBINE
WILL HELP TO GREATLY NARROW THE T/TD SPREAD UNDER PARTIAL CLEARING
SKIES WITH DIMINISHING WIND.
LOW TEMPS AROUND SUNRISE SATURDAY WILL VARY FROM THE MID 40S
ACROSS THE NRN AND WRN MTNS...TO AROUND 50F IN THE LOWER SUSQ
VALLEY.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE ATLEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIEN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERSTURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
CURRENT SATELLITE LOOP SHOWS VFR TO MVFR CLOUDS FILLING IN WHERE
EARLIER/MORNING SUNSHINE AND WIDESPREAD VFR WAS NOTED /ACROSS THE
CENTRAL VALLEYS OF PENN AND MID/LWR SUSQ VALLEY AIRFIELDS/.
WIDESPREAD SC/MDT CU WILL CONTINUE TO DEVELOP LATE THIS AFTERNOON
AS A COLD POOL AND TROF ALOFT MOVES SE ACROSS THE REGION. EXPECT
SHOWERS TO DEVELOP AND ADVECT SE DURING THROUGH THE LATE DAY/EARLY
EVENING HOURS. THERE WILL BE SCATTERED RESTRICTIONS AT TIMES IN
THE SHOWERS...ESPECIALLY ACROSS THE NE THIRD TO ONE HALF OF PENN
/ROUGHLY EAST OF A LINE FROM KBFD TO KUNV AND KSEG/.
ADDITIONALLY...A GUSTY NW WIND OF 15 TO 25 WILL DEVELOP LATE
MORNING...PERSISTING THROUGH THE DAY.
A LOW PROBABILITY /TOO LOW TO MENTION IN THE LATEST 18Z TAFS/ FOR
A BRIEF TSRA EXISTS BETWEEN 20Z FRI-00Z SAT ACROSS THE AREA NEAR
AND TO THE EAST OF A LINE FROM KELM...TO KIPT AND KMDT.
PRECIPITATION SHOULD TAPER OFF DURING THE EVENING...AS DIURNAL
HEATING AND INSTABILITY WANES...AND THE UPPER SHORTWAVE AND COOL
POOL ALOFT SLIDES EAST OF THE REGION. EXPECT WINDS TO SLACKEN
AFTER 01Z THIS EVENING AS WELL.
SATURDAY WILL AGAIN FEATURE SOME PATCHY LOW CLOUDS AND FOG EARLY
FOLLOWED BY PARTLY TO MOSTLY SUNNY SKIES DURING THE MID TO LATE
MORNING...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING IN THE
AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.SUN...AM FOG POSSIBLE...OTHERWISE VFR.
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
320 PM EDT THU MAY 22 2014
.SYNOPSIS...
A WARM FRONT WILL DRIFT SLOWLY EAST ACROSS THE SUSQUEHANNA VALLEY
THIS AFTERNOON...SEVERAL HOURS PRIOR TO A COLD FRONT PUSHING
SOUTHEAST ACROSS THE STATE. THESE TWO WEATHER FEATURES WILL
SUPPORT CLUSTERS OF SHOWERS AND THUNDERSTORMS ACROSS THE
SOUTHEAST HALF OF THE STATE THIS AFTERNOON. FRIDAY STILL LOOKS
UNSETTLED AS A STRONG UPPER AIR DISTURBANCE ROLLS THROUGH AND
TOUCHES OFF SHOWERS. THE EXTENDED FORECAST IS FOR A GRADUAL
WARMING TREND BEGINNING THIS WEEKEND...DESPITE SOME SHOWERS
LINGERING SATURDAY IN THE POST- FRONTAL NORTHWEST FLOW.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SFC WARM FRONT EXTENDED FROM THE POCONOS...SOUTH TO NEAR KLNS AT
1845Z...WHILE A COLD FRONT WILL DRIFT SLOWLY SE FROM THE
ALLEGHENIES OF NORTHERN AND WESTERN PENN.
THE AIRMASS IN THE WARM SECTOR IS QUITE UNSTABLE WITH MU CAPES AOA
2000 J/KG ACROSS THE MIDDLE AND LOWER SUSQ VALLEY... HELPING TO
JUICE UP NUMEROUS TSRA /SOME WITH SUPERCELL CHARACTERISTICS/
ACROSS.
A BLEND OF THE 06/12Z OPERATIONAL GUIDANCE LINES UP NICELY WITH
WHERE THE CURRENT CONVECTION IS LOCATED /AT THE JUXTAPOSITION OF
A DISTINCT 850 MB THETA-E RIDGE...THE SFC WARM FRONT...AND THE
NOSE OF A 90KT UPPER LEVEL WNWRLY JET/.
LATEST RAP AND NAM SHOWS A SMALL BULLSEYE OF EHI AOA 1.5 M2/S2
INVOF KSEG AND POINTS TO THE EAST WILL SUPPORT THE BEST POTENTIAL
FOR LOCALIZED SVR TSRA WITH POSSIBLE MESOS AS THE CELLS HEAD SE
AND INTO THE BETTER LLVL SHEAR AND INSTABILITY ACROSS THE MIDDLE
SUSQ VALLEY AND SRN POCONOS.
SVR TSRA WATCH NO. 172 IN EFFECT FOR OUR FAR ERN ZONES...AND RUNS
TIL 8 PM EDT.
SFC DEWPOINTS SHOULD START TO SLOWLY DROP ACROSS THE CENTRAL MTNS
AND ALLEGHENY PLATEAU /EVEN PRIOR TO THE MID TO LATE AFTERNOON
CFROPA /AS A MEAN LLVL WESTERLY WIND FRESHENS...AND THE THETA-E
RIDGE IN THE BOUNDARY LAYER SHIFTS EAST TO THE SUSQ VALLEY/.
A MORE DISTINCT DROP IN SFC DEWPOINT TO THE UPPER 40S WILL OCCUR
IN THE WAKE OF THE CFROPA.
TEMPS WILL BE NEAR NORMAL THIS AFTERNOON...TOPPING OUT CLOSE TO
80F THROUGHOUT THE LOWER SUSQ VALLEY. HOWEVER...TEMPS WILL LEVEL
OFF IN THE NW...THEN EVEN DIP A FEW TO SVRL DEG F THROUGH THE
AFTERNOON HOURS AS THE DRIER/COOLER AIR MOVES IN BEHIND THE COLD
FRONT. 8H TEMPS FALL 8C THROUGH THE DAY OVER THE NWRN COS.
ONCE THE SHOWERS/STORMS IN THE EAST PUSH OUT OF THE AREA IN THE
EVENING...THE REST OF THE NIGHT SHOULD BE UNEVENTFUL WITH DRY AIR
AND SUBSIDENCE TAKING OVER. MINS MAY WELL BE CLOSE TO 40F IN BFD
FRI AM.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
CLOUDS AND SHOWERS WILL LIKELY MOVE BACK IN QUICKLY FROM THE NW
DURING LATE MORNING-EARLY AFTN DUE TO THE FAST APPROACH OF A VERY
STRONG TROUGH ALOFT. WHILE IT DOES NOT DEEPEN AS IT MOVES
OVERHEAD...THE 5H HEIGHTS FALL 10DAM. WILL CONTINUE TO PLACE THE
HIGHEST POPS IN THE EAST...BUT THE MOUNTAINS ALWAYS GIVE A LITTLE
BOOST OF LIFT IN THE ALREADY-FAVORABLE STEEP LAPSE RATES.
THEREFORE...WILL NOT DROP POPS FROM ANY LOCATION ON FRI AFTN.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
AN UPPER-LEVEL TROUGH CROSSING THE INTERIOR NORTHEAST AND NORTHERN
MID-ATLANTIC STATES WILL LINGER ALONG/OFFSHORE THE EASTERN
SEABOARD THRU SATURDAY. THE UPPER LEVEL TROUGHING AND RELATIVELY
COOL CYCLONIC FLOW ALOFT WILL BE REPLACED BY RISING HEIGHTS
EXPANDING NNEWD IN ADVANCE OF A HIGH-LEVEL RIDGE MIGRATING EWD
ACROSS THE SOUTH-CENTRAL U.S. THE UPPER RIDGE IS FORECAST TO
FLATTEN INTO THE MIDDLE OF NEXT WEEK IN ASSOCIATION WITH SHORTWAVE
ENERGY MOVING THROUGH SOUTHEASTERN CANADA. THE MODELS GENERALLY
AGREE ON THE ABOVE MENTIONED LARGE SCALE PATTERN EVOLUTION...WITH
NOTEWORTHY DIFFERENCES CREEPING INTO DETERMINISTIC SOLUTIONS IN
THE OUTER PERIODS. SPECIFICALLY...THE 21/12Z OPRNL GFS IS MUCH
MORE AGGRESSIVE IN LOWERING HEIGHTS OVER THE NORTHEAST/NEW ENGLAND
STATES BY NEXT WED/THU...WHICH RESULTS IN A SIGNIFICANT SPREAD IN
MEDIUM RANGE X/N GFS AND ECMWF BASED MOS TEMPERATURE GUIDANCE.
A MID-LEVEL ANTICYCLONE BUILDING NORTH/EAST FROM THE LWR MS VLY
WILL FAVOR A MORE TYPICAL EARLY-SUMMER PATTERN WITH STRONG
SIGNALS FOR AN UPWARD TEMPERATURE AND HUMIDITY TREND FROM MEMORIAL
DAY INTO THE MIDDLE OF NEXT WEEK. THE POTENTIAL FLY IN THE
OINTMENT MIGHT BE ANY RING OF FIRE CONVECTION THAT COULD THWART
THE PROJECTED WARMING TREND. IN GENERAL EXPECT A BETTER CHANCE FOR
SHOWERS AND AFTN TSTMS INTO THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
NUMEROUS SHOWERS AND LOCALIZED STG TO SVR TSRA WILL CONTINUE TO
TRACK SE ACROSS THE MID AND LOWER SUSQ VALLEY /AND PTS EAST/
LATE THIS AFTERNOON AND WILL LEAD TO BRIEFLY REDUCED VSBYS AND
CIGS /MAINLY MVFR/ ACROSS THE EASTERN HALF OF PENN.
ELSEWHERE...MOST OF CENTRAL AND WESTERN PENN AIRFIELDS WILL STAY
VFR FOR THE REST OF THE DAY /WITHIN THE WARM SECTOR BETWEEN AN
APPROACHING COLD FRONT...AND THE AFOREMENTIONED WARM FRONT IN THE
FAR EAST/.
STRATOCU ASSOC WITH A POOL OF COLD AIR ALOFT WILL LIKELY WORK
INTO THE NW MTNS TONIGHT. COOLING/MOISTENING BLYR...COMBINED WITH
UPSLOPE FLOW...WILL LIKELY CAUSE CIGS TO FALL TO MVFR LATE TONIGHT
AT KBFD. VFR TO OCNL MVFR BKN-OVC STRATOCU DECK WITH SPREAD ACROSS
AT LEAST THE CENTRAL AND NRN PARTS OF PENN BY LATE FRI MORNING
WITH SCATTERED-NUMEROUS SHOWERS DEVELOPING AS A POTENT UPPER LEVEL
TROUGH APPROACHES FROM THE GLAKES REGION.
.OUTLOOK...
SAT...AM LOW CIGS POSS W MTNS.
SUN...PATCHY AM FOG POSSIBLE.
MON...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/DANGELO
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
812 PM EDT FRI MAY 23 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL OUT OVER GEORGIA TONIGHT. SURFACE HIGH
PRESSURE WILL THEN DRIFT EASTWARD FROM THE OHIO VALLEY TO THE
OFFSHORE ATLANTIC WATERS OVER THE WEEKEND. THE REGION IS EXPECTED TO
BE BACK UNDER THE INFLUENCE OF THE BERMUDA HIGH BY EARLY NEXT WEEK
WITH DEWPOINTS AND TEMPERATURES WARMING.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 800 PM EDT FRIDAY...EARLIER CONVECTION HAS EXITED TO THE
SOUTHEAST LEADING TO CALMING CONDITIONS FOR THE CWFA. SURFACE OBS
INDICATE BACKDOOR FRONT HAS MADE ITS WAY TO THE I85 CORRIDOR LEADING
TO LOWERING DEWPOINTS THUS A MORE STABLE ENVIRONMENT. DECIDED TO
GO AHEAD AND CANCEL WW179 FOR THE ENTIRE AREA WITH THIS UPDATE.
WILL CONTINUE TO HIGHLIGHT SLIGHT THUNDER CHANCES ACROSS THE EXTREME
WESTERN UPSTATE AND PORTIONS OF NORTHEAST GA FOR THE NEXT FEW HOURS
DUE TO PROXIMITY TO THE FRONT AND CURRENT STORM OUTFLOW BOUNDARY
PUSHING WESTWARD ALONG I85. OTHERWISE...NO SIGNIFICANT CHANGES MADE
TO THE FORECAST WITH THIS UPDATE.
PREVIOUS DISCUSSION...
AS OF 230 PM EDT...CONVECTION REMAINS LARGELY BENIGN ATTM WITH
MAINLY SCT CU OVER SOME OF THE MTNS AND WRN UPSTATE. UNDER STILL
BRISK MID-UPPER LEVEL NW FLOW...MTN WAVE CIRRUS CONTINUE TO KEEP
MCLDY SKIES OVER THE NC FOOTHILLS AND NW PIEDMONT. THESE AREAS WERE
HIT PRETTY HARD WITH OUTFLOW FROM THE TSTM CLUSTER THIS MORNING AND
APPEAR TO HAVE BEEN KEPT STABLE BY THIS AND TO SOME EXTENT THE
CIRRUS. S AND W OF THIS AREA ISOLATED TSRA ARE STILL
EXPECTED...WHERE 1500-2000 J OF UNCAPPED SBCAPE IS SHOWN ON SPC
MESOANALYSIS. INDEED A COUPLE OF CELLS ARE STARTING TO GO UP OVER
PICKENS COUNTY. THE 12Z NCEP HIRES WINDOW RUNS REINFORCE SUGGESTIONS
OF NUMEROUS HRRR AND RAP RUNS THAT ISOLD ACTIVITY WILL KICK OFF IN
THE SMOKIES AND IN THE UPSTATE EAST OF SPARTANBURG. WITH THE
AFOREMENTIONED INSTABILITY AND EFFECTIVE BULK SHEAR OF 35-45
KT...ALONG WITH SUBSTANTIAL DCAPE OVER 1000 J/KG...STORMS WILL BE
QUITE CAPABLE OF DMGG WIND/HAIL. SVR WATCH JUST ISSUED FOR THE SRN
TIER OF THE NC MTNS/FOOTHILLS...THE UPSTATE AND NE GA.
HIGH PRESSURE BEGINS TO BUILD ACRS THE GREAT LAKES AND OHIO VALLEY
THRU TONIGHT. COLD FRONT CONTINUES TO BE PROGGED TO PUSH SWD THRU
MOST OF THE NC MTNS AND PIEDMONT BY DAYBREAK...PUSHING THROUGH THE
ERN SC PIEDMONT THEREAFTER. IN THE WAKE OF THE FRONT THINGS REMAIN
STABLE THROUGH THE DAY. HOWEVER...WITH A FAIRLY FLAT UPPER RIDGE
REMAINING OVER THE GULF STATES...THE FRONT DOES NOT APPEAR TO FULLY
IMPACT THE SAVANNAH RIVER VALLEY AND WRN UPSTATE. HOWEVER SUBSIDENCE
ALOFT APPEARS TO BE ENOUGH TO WEAKEN LAPSE RATES TO THE POINT THAT
ONLY LIMITED CONVECTION WILL BE POSSIBLE IN THIS AREA. GFS AND NAM
CONTINUE TO PRODUCE HEFTY SBCAPE VALUES OVER 1000 J/KG WEST OF
GSP...BUT SREF PROBS SUGGEST VALUES MOST LIKELY WILL NOT GET THIS
HIGH. I WILL INCLUDE A SCHC FOR DIURNAL SHWRS/TSTMS ALONG THE SRN
ESCARPMENT AND AREAS JUST SOUTH WHERE THE BEST INSTABILITY IS
SUGGESTED. HIGHS WILL BE NEAR NORMAL IN THE MORE CONTINENTAL AIRMASS
BUT WITH BRIGHT SUNSHINE.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM FRIDAY...ONLY SUBTLE CHANGES ARE EXPECTED TO THE
OVERALL UPPER PATTERN FROM SUNDAY INTO MONDAY...MEANING WE SHOULD
REMAIN UNDER A NW FLOW ALOFT BUT THAT HEIGHTS SHOULD RISE A BIT AS
THE TROF OFF THE EAST COAST DEAMPLIFIES. THIS PATTERN WILL ALLOW THE
CENTER OF SURFACE HIGH PRESSURE TO MIGRATE FROM THE MIDWEST/OH
VALLEY REGION TO A POSITION OFF THE SOUTHEAST COAST ON SUNDAY. ONCE
THIS HAPPENS...WE CAN EXPECT SOME RETURN OF MOISTURE FROM THE SOUTH
AND SOME WEAK WARM ADVECTION. THAT WILL PUT THE WESTERN CAROLINAS
AND NE GEORGIA BACK INTO A REGIME WHERE MAINLY DIURNAL SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE. PRECIP CHANCES WERE LIMITED TO A
SLIGHT CHANCE ACROSS MOST OF THE AREA SUNDAY OWING TO THE LACK OF
DEVELOPMENT SEEN IN THE NAM...BUT THEN WERE ALLOWED TO GO UP TO A
CHANCE ACROSS MOST OF THE REGION MONDAY AS MOISTURE AND INSTABILITY
WERE INCREMENTALLY BETTER. TEMPS WILL CREEP UP A BIT FOR SUNDAY...
AND THEN RISE ABOUT A CATEGORY HIGHER FOR MONDAY...AROUND 80 IN THE
MTN VALLEYS AND MIDDLE 80S E OF THE MTNS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 145 PM FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
TUESDAY WITH THE PERSISTENT UPPER RIDGE ANCHORED OVER THE CENTRAL
CONUS AND AN EMBEDDED H5 LOW DRIFTING SLOWLY EASTWARD OVER THE
SOUTHERN PLAINS. SIMULTANEOUSLY...A CLOSED UPPER LOW IS EXPECTED TO
DROP DOWN OVER EXTREME NORTHERN NEW ENGLAND AND REMAIN OVER THAT
REGION FOR MOST OF THE PERIOD. IN TERMS OF THE SYNOPTIC PATTERN
EVOLUTION OVER OUR REGION...WE DONT EXPECT ANY SIG CHANGES THRU DAY
7 WITH THE DOMINANT UPPER RIDGE REMAINING IN PLACE THRU THE PERIOD.
AT THE SFC...WE BEGIN THE PERIOD UNDER LIGHT SLY FLOW WITH A TYPICAL
BERMUDA HIGH IN PLACE TO OUR EAST. EARLY IN THE DAY...A FAIRLY
ROBUST LOW DEEPENS OVER EXTREME NORTHERN NEW ENGLAND AND BRINGS A
SWATH OF COOLER AND DRIER AIR TOWARDS THE FCST AREA. THE MODELS
DIFFER ON HOW FAR SOUTH THIS LOW WILL MAKE WITH THE GFS BRINGING IT
QUITE A BIT FARTHER SOUTH THAN THE ECMWF AND CMC MODELS. I WILL
CONTINUE TO PUT MORE EMPHASIS ON THE ECMWF AND CMC SOLUTIONS FOR THE
TIME BEING AND THUS I DONT EXPECT THE COOLER/DRIER AIR TO PENETRATE
AS FAR SOUTH AS THE GFS SUGGESTS. ONCE THIS LOW MOVES WELL
OFFSHORE...ANOTHER CANADIAN HIGH TRIES TO PUSH SOUTHWARD AND INTO
THE REGION...HOWEVER ITS LOOKING LIKE IT WILL DISSIPATE FAIRLY QUICKLY
ONCE IT MAKES TO THE CAROLINAS.
AT ANY RATE...NO MAJOR CHANGES WERE NEEDED TO THE SENSIBLE FCST. I
DID INCREASE POPS OVER SOME PORTIONS OF THE CWFA TO SOLID CHANCE FOR
WIDELY SCT DIURNAL SHOWERS AND TS FOR WED AND THURS. OTHERWISE...I
CARRY A SLIGHT TO SOLID CHANCE FOR SH AND TS EACH DAY OF THE PERIOD.
IN ADDITION...IT IS TOO EARLY TO MENTION ANY THREAT OF SVR OR WELL
ORGANIZED CONVECTION AT THIS POINT. TEMPS SHOULD START OUT 5 TO 10
DEGREES ABOVE NORMAL FOR LATE MAY AND GRADUALLY DROP THRU THE PERIOD
WITH HIGHS RIGHT AROUND NORMAL BY NEXT FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD AS BACK DOOR COLD FRONT PUSHES FURTHER TO THE SOUTH. WINDS
WILL REMAIN NORTHERLY AT ALL SITES OVERNIGHT AND INTO THE LATE
MORNING HOURS BEFORE SWITCHING SOUTHERLY AT THE SC SITES AS HIGH
PRESSURE SHIFTS SOUTHEAST ALLOWING FOR THE RETURN OF WEAK SOUTHERLY
FLOW. CURRENT CU FIELD WILL ERODE NEAR OR JUST AFTER SUNSET GIVING
WAY TO A FEW HIGH LEVEL CIRRUS THROUGH THE PERIOD WITH A FEW LOW VFR
CU POSSIBLE AT THE SC SITES TOMORROW AFTERNOON WHERE THE BEST
BOUNDARY LAYER MOISTURE WILL RESIDE.
OUTLOOK...DRY HIGH PRESSURE BUILDS IN SATURDAY. VERY ISOLATED
SHRA/TSRA ARE POSSIBLE SAT/SUN AFTNS. AFTN CONVECTION COVERAGE IS
EXPECTED TO INCREASE SOMEWHAT FOR MONDAY AND TUESDAY...AS DEEPER
MOISTURE RETURNS.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...CDG/WIMBERLEY
SHORT TERM...PM
LONG TERM...JPT
AVIATION...CDG
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
236 PM MDT THU MAY 22 2014
.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 230 PM MDT THU MAY 22 2014
CURRENT SURFACE MAP PLACES HIGH PRESSURE ACROSS MINNESOTA...WITH
RETURN FLOW ACROSS THE HIGH PLAINS. UPPER LOW CONTINUES TO SPIN
ACROSS THE SOUTHWESTERN U.S. WITH RIDGE AXIS ACROSS THE NORTHERN
PLAINS. MLCAPE AROUND 1000 J/KG ACROSS NORTHEAST WYOMING/FAR
WESTERN SOUTH DAKOTA...HOWEVER WEAK CAP AND LACK OF FORCING HAS
KEPT THUNDERSTORM DEVELOPMENT ACROSS THE BLACK HILLS. MARGINAL
SHEAR FOR ROTATING UPDRAFTS. VERY SLOW STORM MOVEMENT. MAIN
THREAT THROUGH THIS EVENING WILL BE SMALL HAIL AND LOCALLY HEAVY
RAINFALL. LATEST RUN OF THE HRRR KEEPS SOME THUNDERSTORM ACTIVITY
ACROSS NORTHEAST WYOMING/WESTERN SOUTH DAKOTA UNTIL AFTER
MIDNIGHT.
SIMILAR SETUP ACROSS THE AREA FOR FRIDAY. MAIN DIFFERENCE WILL BE
STRONGER SHORTWAVE LIFTING NORTHWARD THROUGH WYOMING/WESTERN
NEBRASKA FRIDAY AFTERNOON. WITH STRONGER FORCING...MORE WIDESPREAD
THUNDERSTORM ACTIVITY FRIDAY AFTERNOON/EVENING. SHEAR A LITTLE
STRONGER...SO A FEW SEVERE HAIL STORMS POSSIBLE. SLOW MOVEMENT AND
HIGH PRECIPITABLE WATER WILL RESULT IN LOCALLY HEAVY RAINFALL.
&&
.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 230 PM MDT THU MAY 22 2014
SOUTHWEST FLOW ALOFT REMAINS ACROSS THE REGION THIS WEEKEND...WITH
SEVERAL SHORTWAVE DISTURBANCES EJECTING OUT OF A PERSISTENT TROF/CUT
OFF LOW OVER THE WESTERN UNITED STATES. CHANCES FOR SHOWERS AND
THUNDERSTORMS WILL CONTINUE SATURDAY AND SUNDAY...WITH THE POTENTIAL
FOR A FEW STRONG TO SEVERE STORMS EACH DAY. MEDIUM RANGE MODELS
CONTINUE TO SHOW SOMEWHAT GOOD AGREEMENT ON THE TRACK AND TIMING OF
UPPER LOW AS IT FINALLY MOVES FROM THE SOUTHWEST CONUS INTO THE
CENTRAL PLAINS LATE THROUGH THE HOLIDAY WEEKEND. CHANCES FOR PCPN
SHOULD DECREASE ACROSS MUCH OF THE AREA BY MONDAY AS THE LOW TRACKS
SOUTH AND EAST OF THE REGION. CHANCES FOR PCPN COULD INCREASE AGAIN
FOR THE SECOND HALF OF THE WEEK AS FLOW ALOFT RETURNS TO THE
SOUTHWEST. TEMPERATURES WILL BE A BIT ABOVE AVERAGE THROUGH THE
PERIOD...WITH HIGHS IN THE 70S AND LOWER 80S ON THE PLAINS...60S AND
LOWER 70S ACROSS THE BLACK HILLS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 230 PM MDT THU MAY 22 2014
VFR CONDITIONS ARE GENERALLY EXPECTED TONIGHT AND FRIDAY. CHANCES
FOR SHOWERS AND THUNDERSTORMS CAN BE EXPECTED THIS EVENING ACROSS
NORTHEAST WY AND FAR WRN SD. SHOWERS AND STORMS ARE AGAIN EXPECTED
FRIDAY AFTERNOON. MVFR CONDITIONS ARE POSSIBLE IN THE VICINITY OF
ANY HEAVIER SHOWERS AND STORMS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...7
LONG TERM...13
AVIATION...13
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
256 PM EDT THU MAY 22 2014
.SHORT TERM (TONIGHT AND FRIDAY)...
SO FAR THE CAP HAS BEEN EFFECTIVE IN SUPPRESSING DEEP CONVECTION
ACROSS THE REGION. SHOWERS HAVE DEVELOPED IN SRN KY...ALTHOUGH NOT
YET TO THE EXTENT THAT THE HRRR AND RUC HAVE BEEN DEPICTING. ANY
STORMS THAT DEVELOP WILL MOVE SE AND ENCOUNTER PLENTY OF CAPE...SO
THE SEVERE THREAT OF LARGE HAIL AND DAMAGING WINDS
REMAINS...ALTHOUGH COVERAGE OF TSTMS MAY NOT BE MORE THAN
SCATTERED. WILL CARRY CHANCE POPS INTO THE EVENING IN THE PLATEAU
AND CENTRAL VALLEY.
THE RIDGE NEAR THE GULF COAST TODAY WILL SHIFT SOUTHWARD
TOMORROW...AND THE AXIS OF MAX THETA-E AT 850 MB SHIFTS SOUTH AS
WELL. MOST TSTM ACTIVITY TOMORROW WILL BE IN THE SOUTHERN
VALLEY...HOWEVER WITH THE CONTINUED LACK OF UPPER LEVEL SUPPORT AND
LIMITED MOISTURE...POPS WILL REMAIN IN THE CHANCE RANGE. THE CAP
LOOKS WEAKER IN FORECAST SOUNDINGS TOMRROW COMPARED TO TODAY. MLCAPE
WILL AGAIN BE PLENTIFUL...IN THE 3000-3500 J/KG RANGE...SO ANY
STORMS THAT CAN DEVELOP WILL HAVE A LARGE HAIL/DAMAGING WIND
POTENTIAL.
.LONG TERM (FRIDAY NIGHT THROUGH THURSDAY)...
BY FRIDAY NIGHT THE FRONT IS PROGGED TO SHIFT SOUTHWARD INTO
GEORGIA...SOUTH CAROLINA AND ALABAMA WHICH WILL ALLOW MORE STABLE
AIR TO FILTER INTO AREAS NORTH OF THE BOUNDARY. THUS RAIN CHANCES
DIMINISH FRIDAY NIGHT AND SATURDAY. THE FRONT WILL BEGIN MOVING
SLOWLY BACK TO THE NORTH ON SUNDAY AND THE SOUTHERN TN AND
SOUTHWEST NORTH CAROLINA COULD SEE THUNDERSTORMS DEVELOP. THE FRONT
WILL CONTINUE MOVING NORTH OVERNIGHT SUNDAY INTO MONDAY AND BRING
CHANCES FOR THUNDERSTORMS FOR THE ENTIRE FORECAST AREA EACH
AFTERNOON THROUGH THURSDAY.
TEMPERATURES ON SATURDAY WILL WILL GENERALLY RANGE FROM THE MID AND
UPPER 70S TO LOWER 80S. SUNDAY MORNING WILL BE RATHER COOL WITH
TEMPERATURES IN THE 40S AND 50S. THIS WILL BE THE COOLEST PERIOD FOR
THE REMAINDER OF THE WEEKEND INTO NEXT WEEK WHEN OVERNIGHT LOWS WILL
RANGE FROM THE MID 50S TO LOWER 60S AND HIGH TEMPERATURES WILL PUSH
NEAR 90 DEGREES BY WEDNESDAY GENERALLY SOUTH OF I-40. MAX
TEMPERATURES COOL SLIGHTLY BY THURSDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 66 87 59 82 / 20 30 10 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 65 83 56 80 / 30 20 10 0
OAK RIDGE, TN 64 83 56 81 / 30 20 10 0
TRI CITIES AIRPORT, TN 57 78 48 80 / 20 10 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/AC
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1034 AM EDT THU MAY 22 2014
.DISCUSSION...
THE 12Z OHX SOUNDING SHOWS A STRONG CAP...AND RUC FORECAST
SOUNDINGS SHOW THIS CAP REMAINING IN PLACE THROUGH THE AFTERNOON.
IT IS STRONGEST IN SOUTHERN AREAS AND WEAKEST NORTH. THE QUESTION
IS WHETHER THERE WILL BE ENOUGH FORCING TO OVERCOME THE CAP. THE
RUC AND NAM SHOW NO UPPER LEVEL SUPPORT COMING...SO ANY CONVECTION
THAT DEVELOPS WILL NEED LOW LEVEL FORCING AND BOUNDARIES TO
DEVELOP. WE DO HAVE BOUNDARIES IN THE AREA FROM THE OVERNIGHT
SHOWERS...AND CONVECTION THAT IS EXPECTED TO INITIATE IN CNTRL KY
WILL MOVE SE..PROVIDING ADDITIONAL BOUNDARIES FOR CONVECTIVE
INITIATION. RUC AND HRRR HAVE MOST ACTIVITY IN THE PLATEAU AND
CENTRAL VALLEY.
ANY STORMS THAT FORM WILL HAVE ABUNDANT ENERGY AVAILABLE FOR
GROWTH. MLCAPE VALUES WILL APPROACH 2500 J/KG IN THE PLATEAU. THUS
LARGE HAIL APPEARS TO BE THE MAIN THREAT...WITH DAMAGING WINDS A
THREAT AS WELL AS FORECAST SOUNDINGS SHOW AN INVERTED-V PROFILE.
WHILE DEEP SHEAR VALUES WILL SUPPORT SOME SUPERCELLS...WEAK LOW
LEVEL SHEAR AND HIGH LCLS DO NOT FAVOR TORNADOES.
FOR THE UPDATE...POPS/WX/CLOUDS/QPF WILL BE ADJUSTED TO BETTER
MATCH FAVORED PRECIP AREAS...AND TO ADD A MENTION OF THE LARGE
HAIL/DAMAGING WIND THREAT. TEMPERATURES APPEAR ON TRACK.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
336 AM EDT THU MAY 22 2014
.SHORT TERM (TODAY THROUGH SUNDAY)...NEAR TERM...A COMPLEX OF
SHOWERS AND THUNDERSTORMS OVER NORTHERN KENTUCKY/SOUTHERN INDIANA.
THE LATEST RAP WEAKENS THIS ACTIVITY AS IT MOVES TOWARD THE
FORECAST AREA...HOWEVER...CONVECTION STILL REMAINS STRONG. WE WILL
MONITOR THIS ACTIVITY THE REST OF THE MORNING FOR POSSIBLE UPDATE
FOR MORNING POPS.
AN OUTFLOW BOUNDARY REMAINS BETWEEN KNOXVILLE AND MORRISTOWN. THIS
BOUNDARY AS WELL AS BOUNDARY FROM KENTUCKY CONVECTION WILL LIKELY
BE MAIN FOCUS FOR AFTERNOON RE-DEVELOPMENT. AIRMASS MOST OF THE
AREA...ESPECIALLY TENNESSEE...WILL BECOME QUITE UNSTABLE WITH
MLCAPES OF 2500-3000 J/KG. FORECAST SOUNDINGS SHOW FAIRLY LARGE
HAIL CAPES WITH FAVORABLE WET BULB ZERO HEIGHTS FOR LARGE HAIL...
UP TO GOLFBALL SIZE. ALSO...FAVORABLE THERMODYNAMICS AND SOME WINDS
ALOFT FOR DAMAGING WINDS AS WELL...FOR THIS AFTERNOON AND EVENING.
A COLD FRONT WILL MOVE SOUTH ACROSS THE AREA TONIGHT AND FRIDAY
WITH ANOTHER ROUND OF ISOLATED STRONG CONVECTION AGAIN FOR THE
SOUTHEAST TENNESSEE AND SOUTHWEST NORTH CAROLINA.
FRONTAL BOUNDARY MOVES SOUTH OF THE AREA FOR SATURDAY...THEN
DISSIPATES BY SUNDAY. SOME MOISTURE RETURN FOR SUNDAY TO INCLUDE
SLIGHT POPS FOR THE SOUTHERN AREAS DURING THE AFTERNOON/EVENING.
GENERALLY FOLLOWED THE GFS MOS...EXCEPT FOR THE NORTHERN HALF OF
THE AREA TODAY. WENT A COUPLE DEGREES COOLER DUE TO EXPECTED
CONVECTION AND CLOUDS.
.LONG TERM (SUNDAY NIGHT THROUGH WEDNESDAY)...MODELS ARE IN GENERAL
AGREEMENT WITH THE SYNOPTIC-SCALE PATTERN FOR NEXT WEEK...AND REVEAL
AN UNSEASONABLY WARM AND HUMID AIR MASS OVER THE FORECAST AREA WITH
A WEAKENING UPPER-LEVEL TROUGH APPROACHING FROM THE PLAINS. ISOLATED
CONVECTION IS EXPECTED ON SUNDAY NIGHT AND MONDAY...WITH THE
APPROACHING UPPER-LEVEL TROUGH HELPING TO INCREASE THE AREAL
COVERAGE OF CONVECTION BY TUESDAY INTO WEDNESDAY. AS FOR TEMPS...
WILL GENERALLY TREND CLOSE TO THE GFS GUIDANCE NUMBERS FOR NEXT
WEEK...WHICH ARE IN GOOD AGREEMENT WITH THE ENSEMBLE MEANS.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 89 66 87 61 / 20 20 30 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 86 63 84 57 / 60 20 20 10
OAK RIDGE, TN 87 63 84 56 / 60 20 20 10
TRI CITIES AIRPORT, TN 83 57 80 48 / 40 20 10 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1058 PM CDT FRI MAY 23 2014
.UPDATE...
MAIN REASON FOR UPDATE WAS TO INCREASE POPS ACROSS THE WESTERN TEXAS
AND OKLAHOMA PANHANDLES AS CONVECTION MOVING ONTO THE EASTERN PLAINS
OF NEW MEXICO CONTINUES TO MOVE TO THE EAST.
&&
.PREV DISCUSSION... /ISSUED 654 PM CDT FRI MAY 23 2014/
AVIATION...
/00Z TAFS/ THE TERMINALS ARE CURRENTLY IN BETWEEN SHOWERS AND
THUNDERSTORMS IN OKLAHOMA AND OVER THE MOUNTAINS IN CENTRAL NEW
MEXICO. THE CONVECTION IN NEW MEXICO IS SLOWLY MOVING TO THE
NORTHEAST WHERE THE HRRR AND TTU WRF SUGGEST THIS CONVECTION ENTERING
THE SOUTHWEST TEXAS PANHANDLE...INCLUDING MOVING NEAR THE KAMA
TERMINAL BETWEEN 08-11Z. POSSIBLE FOR THESE STORMS TO MOVE NEAR THE
KAMA TERMINAL HOWEVER CONFIDENCE IN THIS OCCURRING IS NOT HIGH ENOUGH
TO INSERT -TSRA INTO THE FORECAST. IN FACT WHILE CONVECTION WILL
REMAIN PROBABLE THROUGH THE 24 HOUR FORECAST PERIOD...HAVE OPTED TO
NOT PUT IN A MENITON OF -TSRA IN ANY OF THE TERMINALS GIVEN THE
UNCERTAINTY ON WHERE AND WHEN THEY WILL IMPACT THE TERMINALS. OUTSIDE
OF THE RAIN POTENTIAL...LOW END VFR CONDITIONS WILL DETEORIRATE TO
LOW END MVFR OVERNIGHT. POSSIBLE FOR CIGS TO LOWER EVEN FUTHER TO IFR
AND WILL CONTINUE TO MONITOR FOR THAT POSSIBILITY.
ANOTHER CONCERN WILL BE THE POTENTIAL FOR FOG. LIGHT UPSLOPE
SOUTHEAST FLOW WILL DRAW IN GREATER BOUNDARY LAYER MOISTURE OVER
NORTH TEXAS /WHERE SFC DEWPOINTS ARE CURRENTLY IN THE LOW-MID 60S/.
THINK THE GREATER POTENTIAL FOR FOG WILL BE AT KAMA AS WINDS WILL BE
MORE OUT OF THE SOUTH THAN THE SOUTHEAST AT KGUY/KDHT LATE
TONIGHT/EARLY SAT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY.
CLK
PREV DISCUSSION... /ISSUED 356 PM CDT FRI MAY 23 2014/
DISCUSSION...
THROUGH TONIGHT: WE`VE SEEN A LULL IN THE RAIN THIS AFTERNOON IN MOST
PLACES AS STRONG SUBSIDENCE PREVAILS IN THE WAKE OF A DEPARTING
SHORTWAVE TROUGH. THE LULL MAY OR MAY NOT BE SHORT-LIVED AS
THUNDERSTORMS HAVE RAPIDLY DEVELOPED ALONG THE SANGRE DE CRISTO AND
SACRAMENTO MOUNTAINS IN CENTRAL NEW MEXICO. THANKS TO SOME CLEARING,
THE AIR MASS EAST OF THESE STORMS HAS RECOVERED FROM EARLY MORNING
CONVECTION WITH MIXED LAYER CAPE VALUES BETWEEN 1000 AND 1500 J/KG.
THEREFORE, THESE STORMS WILL LIKELY PERSIST AND INTENSIFY THIS
AFTERNOON AS THEY MOVE OFF THE MOUNTAINS. HOWEVER, AS THE CONVECTION
APPROACHES THE STATE LINE, IT WILL LIKELY LOSE ITS PUNCH SINCE THE
AIR MASS HAS NOT RECOVERED MUCH ACROSS THE WESTERN PANHANDLES.
NONETHELESS, SINCE THIS ACTIVITY IS MOUNTAIN-INDUCED, IT WILL
PROBABLY MAKE IT INTO THE WESTERN PANHANDLES AFTER 8 PM AND SLOWLY
SPREAD EASTWARD BEFORE DISSIPATING BY 3 AM. THINK THE HIGHEST
CHANCES FOR RAIN WILL BE WEST OF A BOISE CITY TO AMARILLO LINE.
SATURDAY-SUNDAY NIGHT: PROVIDED NO THUNDERSTORM COMPLEXES ROLL ACROSS
THE AREA TONIGHT OR SATURDAY MORNING, THE STAGE SHOULD BE SET FOR A
GOOD OPPORTUNITY FOR THUNDERSTORMS SATURDAY AFTERNOON THROUGH
SATURDAY NIGHT AS THE UPPER LOW SLOWLY MOVES OUR WAY. HEAVY RAIN IS
ALL BUT GUARANTEED SATURDAY EVENING AND NIGHT, ESPECIALLY WITH THE
STRONGER STORMS. THIS MAY CAUSE MORE FLOODING OR FLASH FLOODING
ISSUES. THE FLASH FLOODING THREAT WILL ONLY BE ENHANCED IF A
STATIONARY CONVECTIVE COLD POOL BECOMES ESTABLISHED AND ALLOWS
THUNDERSTORMS TO TRAIN OVER THE SAME AREA. A FEW SEVERE STORMS ALSO
APPEAR TO BE A GOOD BET BETWEEN 2 PM AND 11 PM AS LONG AS NO
OVERNIGHT THUNDERSTORM COMPLEXES OCCUR TONIGHT. MIXED LAYER CAPE
VALUES WILL AVERAGE AROUND 1500 J/KG TOMORROW AFTERNOON WITH DEEP
SHEAR VALUES INCREASING TO UP TO 30 KT BY LATE TOMORROW AFTERNOON
ACROSS THE WESTERN PANHANDLES. ORGANIZED MULTICELLS WILL BE THE
PREDOMINANT CONVECTIVE MODE, AND THEY WILL POSE A RISK FOR DAMAGING
WINDS AND LARGE HAIL. SUNDAY`S SEVERE POTENTIAL WILL HINGE GREATLY ON
HOW FAST CONVECTION DISSIPATES/MOVES OUT OF THE AREA LATE SATURDAY
NIGHT. IF THERE IS NO/VERY LITTLE PRE-CONVECTIVE CONTAMINATION
DURING THE MORNING AND EARLY AFTERNOON HOURS ON SUNDAY, A HEALTHY
RISK FOR SEVERE WEATHER LOOKS LIKELY, ESPECIALLY EAST OF AN ELKHART
TO HEREFORD LINE WHERE MIXED LAYER CAPE VALUES MAY EXCEED 2000 J/KG
AND DEEP LAYER SHEAR VALUES INCREASE UP TO 40 KT. HODOGRAPH PROFILES
AND THE COMBINATION OF THE BUOYANCY AND SHEAR SUGGEST THE POTENTIAL
FOR A MIXED CONVECTIVE MODE, INCLUDING SUPERCELLS. IF A DOMINANT
SUPERCELL DEVELOPS, AN ISOLATED TORNADO WILL BE POSSIBLE GIVEN
RELATIVELY LOW LCL HEIGHTS, MINIMAL LOW-LEVEL CIN, AND SUFFICIENT LOW-
LEVEL SHEAR (0-1 KM SHEAR VALUES AROUND 20 KT). HOWEVER, SUNDAY`S
SEVERE POTENTIAL WILL GREATLY DEPEND ON WHAT HAPPENS WITH CONVECTION
ON SATURDAY NIGHT.
MEMORIAL DAY-FRIDAY: ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED ON
MEMORIAL DAY, ESPECIALLY EAST OF AN ELKHART TO HEREFORD LINE. HEAVY
RAIN AND SEVERE WEATHER WILL REMAIN A DISTINCT POSSIBILITY AGAIN
DURING THE AFTERNOON AND EVENING HOURS. THUNDERSTORM CHANCES START
TO DECREASE FROM WEST TO EAST ON TUESDAY AS THE UPPER LOW BEGINS
SHIFT EAST OF THE AREA. HOWEVER, WITH THE DRYLINE REMAINING IN PLACE
THROUGHOUT THIS PERIOD, THE PATTERN WILL REMAIN FAVORABLE FOR
THUNDERSTORM CHANCES WEDNESDAY THROUGH FRIDAY, ESPECIALLY IF LIFTING
MECHANISM INTERACT WITH THE MOIST, MODESTLY UNSTABLE AIR MASS.
JACKSON
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH
FRIDAY AS EITHER RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE 20
PERCENT AND/OR 20-FOOT WINDS WILL REMAIN BELOW 15 MPH. WETTING RAINS
ARE EXPECTED TO CURB FUEL DRYNESS. THUNDERSTORMS ARE EXPECTED ALMOST
MOST DAYS...AND THEY COULD POSE A SMALL RISK FOR FIRE STARTS DUE TO
LIGHTNING.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
855 PM CDT FRI MAY 23 2014
.UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
&&
.DISCUSSION...
CIRRUS CONTINUES TO SPREAD ACROSS THE AREA THIS EVENING THANKS TO
CONVECTION IN CENTRAL TEXAS. REGARDING THE CAMELOPARDALIDS METEOR
SHOWER... CIRRUS WILL LIKELY REMAIN RATHER THICK WITH BREAKS
POSSIBLE. TEMPERATURES WILL BE SIMILAR TO YESTERDAY AS 850
TEMPERATURES REMAIN AROUND 16C TOMORROW. FORECAST HAS THE COVERED.
NO UPDATE REQUIRED AT THIS TIME. 23
&&
.CLIMATE...
THE LAST COUPLE OF MONTHS HAVE BEEN BELOW NORMAL ACROSS THE AREA.
BUT HOW COLD HAS IT BEEN? THE AVERAGE TEMPERATURE AT THE CITY OF
HOUSTON (KIAH) FOR OCTOBER 1ST THROUGH MAY 22ND IS 60.4. THIS IS
THE 12TH COOLEST ON RECORD FOR THE PERIOD OF 10/1 - 5/22. COLLEGE
STATION HAS ALSO YET TO REACH 90 DEGREES SO FAR THIS YEAR. 23
&&
.PREV DISCUSSION... /ISSUED 553 PM CDT FRI MAY 23 2014/
DISCUSSION...
SEE 00Z AVIATION DISCUSSION.
AVIATION...
CIRRUS DEBRIS FROM CONVECTION OVER WEST TEXAS WILL MOVE OVER SE TX
THIS EVENING. MODELS QUITE AGGRESSIVE WITH LOW CLOUDS OVERNIGHT
BUT LEANED A BIT TOWARD THE HRRR WHICH KEEPS THINGS MAINLY VFR
THROUGH 12Z WITH A BRIEF WINDOW OF MVFR CIGS BETWEEN 12-16Z SAT
MORNING. GENERALLY VFR CONDS EXPECTED SAT AFTN/EVENING. 43
PREV DISCUSSION... /ISSUED 332 PM CDT FRI MAY 23 2014/
DISCUSSION...
WESTERN TROF MAKING SLOW BUT GRADUAL EASTWARD PROGRESS AND SHOULD
CONTINUE DOING SO FOR THE NEXT SEVERAL DAYS. AREA WX SHOULD REMAIN
ABOUT THE SAME THRU THE WEEKEND AND WE`LL MOSTLY BE UNDER THE
INFLUENCE OF THE WESTERN PERIPHERY OF THE RIDGE AND DRIER AIR
SITUATED TO OUR EAST. BUT AS THE TROF MAKES FURTHER EWD THEN SEWD
PROGRESS (OK/TX PANHANDLE MON, OK TUE, TEXARKANA WED, TX/LA BORDER
THURS) EXPECT PW`S TO CLIMB AND THE REGION TO FALL MORE UNDER THE
INFLUENCE OF THE TROF. ECMWF HAS ACTUALLY TRENDED MORE TO THE GFS
SOLN FOR A CHANGE AND THE MODELS ARE ACTUALLY IN PRETTY GOOD AGREEMENT.
ASSUMING THIS VERIFIES IT LOOKS LIKE SCT SHRA/TSRA WILL BE A
DAILY POSSIBILITY INLAND - MORE ISOLATED COAST MON AFTN AND BEYOND.
THOUGH IMPULSES ROTATING AROUND THE TROF COULD REMAIN TRIGGERS AT
ANY TIME, BASED ON TIMING & LOOKS OF QPF FIELDS MOST LOOKS DIURNALLY
DRIVEN W/ DAYTIME HEATING & SEABREEZE BEING PRIMARY TRIGGERS. NUDGED
POPS UP SLIGHTLY ACROSS N-NE 2/3 OF THE CWA NEXT WEEK. WILL PROBABLY
NEED TO CONTINUE TWEAKING UP WITH MODEL CONSISTENCY/CONFIDENCE IN
THE DAYS TO COME.
REGARDING TONIGHT`S CAMELOPARDALIDS METEOR SHOWER:
EXPECT VARIABLE PERIODS OF CIRRUS MOVING OVERHEAD TONIGHT.
HOWEVER...WE`RE NOT EXPECTING QUITE AS MUCH SHRA/TSRA ACTIVITY TO
OUR WEST COMPARED TO LAST NIGHT SO DON`T EXPECT IT TO BE AS THICK
AND MAY QUITE POSSIBLY SEE SOME BREAKS. NASA WEBSITE SAYS PEAK
VIEWING WILL BE BETWEEN 1-3 AM CDT, BUT SHOULD BE ABLE TO SEE SOME
SEVERAL HOURS BEFORE & AFTER THOSE TIMES IF CLOUD COVER COOPERATES.
47
CLIMATE...
THE AVERAGE TEMPERATURE FOR MAY AT THE FIRST-ORDER CLIMATE SITES
CONTINUED TO BE BELOW NORMAL THROUGH YESTERDAY...MAY 22ND. IF THIS
TREND PERSISTS THROUGH THE END OF THE MONTH...BELOW NORMAL MONTHLY
AVERAGE TEMPERATURES WILL HAVE BEEN RECORDED FOR 8 MONTHS IN A ROW
AT COLLEGE STATION AND THE CITY OF HOUSTON...AND FOR 7 MONTHS IN A
ROW AT BOTH THE CITY OF GALVESTON AND HOBBY AIRPORT. THE LAST TIME
HOUSTON RECORDED EIGHT CONSECUTIVE MONTHS WITH BELOW NORMAL TEMPS
WAS JUN 1975 THROUGH JAN 1976.
HERE ARE THE MONTHLY AVERAGE TEMPERATURE DEPARTURES FOR OCTOBER 2013
THROUGH APRIL 2014 AND FOR MAY 1ST THROUGH 22ND...
SITE OCT NOV DEC JAN FEB MAR APR MAY 1-22
IAH -0.2 -4.2 -3.0 -3.6 -1.7 -3.9 -0.1 -2.7
GLS +0.4 -4.1 -4.0 -3.2 -3.2 -3.3 -0.7 -2.7
CLL -0.2 -4.3 -3.7 -3.4 -2.5 -4.6 -0.3 -2.7
HOU +0.5 -3.8 -2.9 -3.0 -1.4 -3.4 -0.2 -3.1
40
MARINE...
ONSHORE WINDS WILL PERSIST WITH HIGH PRESSURE TO THE EAST OVER THE
NORTHERN GULF AND LOW PRESSURE IN THE PLAINS TO THE WEST. AM
EXPECTING AT LEAST ISOLATED SHOWERS AND THUNDERSTORMS TO BEGIN ON
MONDAY OVER THE COASTAL WATERS AND BAYS. 40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 87 68 86 70 / 10 10 10 10 10
HOUSTON (IAH) 68 87 69 86 71 / 10 10 10 10 10
GALVESTON (GLS) 73 83 73 82 74 / 10 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
654 PM CDT FRI MAY 23 2014
.AVIATION...
/00Z TAFS/ THE TERMINALS ARE CURRENTLY IN BETWEEN SHOWERS AND
THUNDERSTORMS IN OKLAHOMA AND OVER THE MOUNTAINS IN CENTRAL NEW
MEXICO. THE CONVECTION IN NEW MEXICO IS SLOWLY MOVING TO THE
NORTHEAST WHERE THE HRRR AND TTU WRF SUGGEST THIS CONVECTION ENTERING
THE SOUTHWEST TEXAS PANHANDLE...INCLUDING MOVING NEAR THE KAMA
TERMINAL BETWEEN 08-11Z. POSSIBLE FOR THESE STORMS TO MOVE NEAR THE
KAMA TERMINAL HOWEVER CONFIDENCE IN THIS OCCURRING IS NOT HIGH ENOUGH
TO INSERT -TSRA INTO THE FORECAST. IN FACT WHILE CONVECTION WILL
REMAIN PROBABLE THROUGH THE 24 HOUR FORECAST PERIOD...HAVE OPTED TO
NOT PUT IN A MENITON OF -TSRA IN ANY OF THE TERMINALS GIVEN THE
UNCERTAINTY ON WHERE AND WHEN THEY WILL IMPACT THE TERMINALS. OUTSIDE
OF THE RAIN POTENTIAL...LOW END VFR CONDITIONS WILL DETEORIRATE TO
LOW END MVFR OVERNIGHT. POSSIBLE FOR CIGS TO LOWER EVEN FUTHER TO IFR
AND WILL CONTINUE TO MONITOR FOR THAT POSSIBILITY.
ANOTHER CONCERN WILL BE THE POTENTIAL FOR FOG. LIGHT UPSLOPE
SOUTHEAST FLOW WILL DRAW IN GREATER BOUNDARY LAYER MOISTURE OVER
NORTH TEXAS /WHERE SFC DEWPOINTS ARE CURRENTLY IN THE LOW-MID 60S/.
THINK THE GREATER POTENTIAL FOR FOG WILL BE AT KAMA AS WINDS WILL BE
MORE OUT OF THE SOUTH THAN THE SOUTHEAST AT KGUY/KDHT LATE
TONIGHT/EARLY SAT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY.
CLK
&&
.PREV DISCUSSION... /ISSUED 356 PM CDT FRI MAY 23 2014/
DISCUSSION...
THROUGH TONIGHT: WE`VE SEEN A LULL IN THE RAIN THIS AFTERNOON IN MOST
PLACES AS STRONG SUBSIDENCE PREVAILS IN THE WAKE OF A DEPARTING
SHORTWAVE TROUGH. THE LULL MAY OR MAY NOT BE SHORT-LIVED AS
THUNDERSTORMS HAVE RAPIDLY DEVELOPED ALONG THE SANGRE DE CRISTO AND
SACRAMENTO MOUNTAINS IN CENTRAL NEW MEXICO. THANKS TO SOME CLEARING,
THE AIR MASS EAST OF THESE STORMS HAS RECOVERED FROM EARLY MORNING
CONVECTION WITH MIXED LAYER CAPE VALUES BETWEEN 1000 AND 1500 J/KG.
THEREFORE, THESE STORMS WILL LIKELY PERSIST AND INTENSIFY THIS
AFTERNOON AS THEY MOVE OFF THE MOUNTAINS. HOWEVER, AS THE CONVECTION
APPROACHES THE STATE LINE, IT WILL LIKELY LOSE ITS PUNCH SINCE THE
AIR MASS HAS NOT RECOVERED MUCH ACROSS THE WESTERN PANHANDLES.
NONETHELESS, SINCE THIS ACTIVITY IS MOUNTAIN-INDUCED, IT WILL
PROBABLY MAKE IT INTO THE WESTERN PANHANDLES AFTER 8 PM AND SLOWLY
SPREAD EASTWARD BEFORE DISSIPATING BY 3 AM. THINK THE HIGHEST
CHANCES FOR RAIN WILL BE WEST OF A BOISE CITY TO AMARILLO LINE.
SATURDAY-SUNDAY NIGHT: PROVIDED NO THUNDERSTORM COMPLEXES ROLL ACROSS
THE AREA TONIGHT OR SATURDAY MORNING, THE STAGE SHOULD BE SET FOR A
GOOD OPPORTUNITY FOR THUNDERSTORMS SATURDAY AFTERNOON THROUGH
SATURDAY NIGHT AS THE UPPER LOW SLOWLY MOVES OUR WAY. HEAVY RAIN IS
ALL BUT GUARANTEED SATURDAY EVENING AND NIGHT, ESPECIALLY WITH THE
STRONGER STORMS. THIS MAY CAUSE MORE FLOODING OR FLASH FLOODING
ISSUES. THE FLASH FLOODING THREAT WILL ONLY BE ENHANCED IF A
STATIONARY CONVECTIVE COLD POOL BECOMES ESTABLISHED AND ALLOWS
THUNDERSTORMS TO TRAIN OVER THE SAME AREA. A FEW SEVERE STORMS ALSO
APPEAR TO BE A GOOD BET BETWEEN 2 PM AND 11 PM AS LONG AS NO
OVERNIGHT THUNDERSTORM COMPLEXES OCCUR TONIGHT. MIXED LAYER CAPE
VALUES WILL AVERAGE AROUND 1500 J/KG TOMORROW AFTERNOON WITH DEEP
SHEAR VALUES INCREASING TO UP TO 30 KT BY LATE TOMORROW AFTERNOON
ACROSS THE WESTERN PANHANDLES. ORGANIZED MULTICELLS WILL BE THE
PREDOMINANT CONVECTIVE MODE, AND THEY WILL POSE A RISK FOR DAMAGING
WINDS AND LARGE HAIL. SUNDAY`S SEVERE POTENTIAL WILL HINGE GREATLY ON
HOW FAST CONVECTION DISSIPATES/MOVES OUT OF THE AREA LATE SATURDAY
NIGHT. IF THERE IS NO/VERY LITTLE PRE-CONVECTIVE CONTAMINATION
DURING THE MORNING AND EARLY AFTERNOON HOURS ON SUNDAY, A HEALTHY
RISK FOR SEVERE WEATHER LOOKS LIKELY, ESPECIALLY EAST OF AN ELKHART
TO HEREFORD LINE WHERE MIXED LAYER CAPE VALUES MAY EXCEED 2000 J/KG
AND DEEP LAYER SHEAR VALUES INCREASE UP TO 40 KT. HODOGRAPH PROFILES
AND THE COMBINATION OF THE BUOYANCY AND SHEAR SUGGEST THE POTENTIAL
FOR A MIXED CONVECTIVE MODE, INCLUDING SUPERCELLS. IF A DOMINANT
SUPERCELL DEVELOPS, AN ISOLATED TORNADO WILL BE POSSIBLE GIVEN
RELATIVELY LOW LCL HEIGHTS, MINIMAL LOW-LEVEL CIN, AND SUFFICIENT LOW-
LEVEL SHEAR (0-1 KM SHEAR VALUES AROUND 20 KT). HOWEVER, SUNDAY`S
SEVERE POTENTIAL WILL GREATLY DEPEND ON WHAT HAPPENS WITH CONVECTION
ON SATURDAY NIGHT.
MEMORIAL DAY-FRIDAY: ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED ON
MEMORIAL DAY, ESPECIALLY EAST OF AN ELKHART TO HEREFORD LINE. HEAVY
RAIN AND SEVERE WEATHER WILL REMAIN A DISTINCT POSSIBILITY AGAIN
DURING THE AFTERNOON AND EVENING HOURS. THUNDERSTORM CHANCES START
TO DECREASE FROM WEST TO EAST ON TUESDAY AS THE UPPER LOW BEGINS
SHIFT EAST OF THE AREA. HOWEVER, WITH THE DRYLINE REMAINING IN PLACE
THROUGHOUT THIS PERIOD, THE PATTERN WILL REMAIN FAVORABLE FOR
THUNDERSTORM CHANCES WEDNESDAY THROUGH FRIDAY, ESPECIALLY IF LIFTING
MECHANISM INTERACT WITH THE MOIST, MODESTLY UNSTABLE AIR MASS.
JACKSON
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH
FRIDAY AS EITHER RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE 20
PERCENT AND/OR 20-FOOT WINDS WILL REMAIN BELOW 15 MPH. WETTING RAINS
ARE EXPECTED TO CURB FUEL DRYNESS. THUNDERSTORMS ARE EXPECTED ALMOST
MOST DAYS...AND THEY COULD POSE A SMALL RISK FOR FIRE STARTS DUE TO
LIGHTNING.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1023 PM CDT FRI MAY 23 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 242 PM CDT FRI MAY 23 2014
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE
HIGH PRESSURE CENTERED OVER THE STATE OF WISCONSIN EARLY THIS
AFTERNOON AND IS PROVIDING TRANQUIL AND SEASONABLE CONDITIONS.
LOOKING OUTSIDE THE REGION...MID-LEVEL THETAE ADVECTION IS PRODUCING
AN AREA OF CLOUD COVER WHICH IS ENTERING WESTERN LAKE SUPERIOR.
ANOTHER AREA OF HIGH CLOUDS IS SPILLING OVER THE MID-LEVEL RIDGE
CENTERED OVER THE GREAT PLAINS INTO IOWA AND NORTHERN ILLINOIS.
WITH SYNOPTIC SCALE FEATURES ONLY MOVING SLIGHTLY TO THE EAST OVER
THE NEXT 24 HOURS...FORECAST CONCERNS INCLUDE CLOUDS AND TEMPS.
TONIGHT...SURFACE HIGH PRESSURE WILL BECOME CENTERED OVER LAKE
MICHIGAN. MID AND HIGH CLOUDS FROM THE THETAE ADVECTION ZONE OVER
WESTERN LAKE SUPERIOR WILL LIKELY SPILL SOUTHEAST ACROSS NORTHERN
AND FAR NORTHEAST WISCONSIN DURING THE EVENING. HAVE KEPT SKIES
PARTLY CLOUDY IN THIS AREA AS A RESULT WHILE STUCK WITH MOSTLY CLEAR
TO CLEAR ELSEWHERE. STUCK WITH THE BETTER VERIFYING BC GUIDANCE FOR
LOW TEMPS WHICH WILL BE SEVERAL DEGREES WARMER THAN LAST NIGHT.
SATURDAY...SURFACE HIGH PRESSURE WILL MOVE TO THE LOWER PENINSULA OF
MICHIGAN. WINDS WILL SHIFT TO THE SOUTHWEST OVER THE STATE...BUT
THE COOLEST LOW LEVEL TEMPS WILL REMAIN OVER CENTRAL AND EASTERN
WISCONSIN. THEREFORE...EXPECT SCT DIURNAL CU IN THIS AREA AND
SHOULD HAVE A LITTLE MORE CIRRUS OVERHEAD TOO. THIS SHOULD NOT STOP
925MB TEMPS FROM WARMING INTO THE MID TO UPPER TEENS WHICH WOULD
PLACE HIGHS IN THE MID TO UPPER 70S AWAY FROM LAKE MICHIGAN.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 242 PM CDT FRI MAY 23 2014
UPPER RIDGING SHOULD KEEP DRY AND WARM WEATHER ACROSS
THE AREA THROUGH SUNDAY EVENING. A SHORTWAVE MOVING THROUGH THE
NORTHERN STREAM WILL COMBINE WITH LOW LEVEL MOISTURE AND CONVERGENCE
TO BRING SCATTERED SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT AND
MEMORIAL DAY. SURFACE DEWPOINTS ARE FORECAST TO RISE INTO THE UPPER
50S TO LOW 60S WHICH RESULTS IN CAPES OF 1000 TO 2000 J/KG. WINDS
ALOFT ARE NOT VERY IMPRESSIVE AND TEMPERATURES ALOFT ARE NOT THAT
COLD. SO WE MAY HAVE A FEW STORMS WITH GUSTY WINDS AND SMALL HAIL
BUT SEVERE STORMS NOT LIKELY AT THIS POINT. A SURFACE FRONT SHOULD
MOVE THROUGH LATE MONDAY NIGHT AND AN UPPER RIDGE GETS ESTABLISHED
OVER THE HIGH PLAINS. A BIG SURFACE HIGH DROPS DOWN FROM ICE COVERED
HUDSON`S BAY INTO THE GREAT LAKES AND SHOULD PRODUCE A DRY EASTERLY
FLOW FROM TUESDAY THROUGH FRIDAY OR SATURDAY.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1023 PM CDT FRI MAY 23 2014
QUIET WX WITH VFR CONDITIONS EXPECTED THE NEXT 24 HRS AS SFC HIGH
LINGERS ACRS THE AREA.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
635 PM MDT FRI MAY 23 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 441 PM MDT FRI MAY 23 2014
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MUCH OF THE
CWA THIS AFTERNOON AS MIDLEVEL ENERGY AND DIFFLUENT FLOW MOVE
OVERHEAD ON THE NORTHEASTERN PERIPHERY OF THE UPPER LOW. RADAR
ESTIMATES OVER THE SNOWY AND SIERRA MADRE MOUNTAINS INDICATE A FEW
TENTHS OF AN INCH OF RAIN HAVE FALLEN OUT OF THE STRONGER
STORMS...AND PERHAPS AS HIGH AS ONE HALF INCH. THIS ACTIVITY IS
GENERALLY MOVING NORTH OFF THE MOUNTAINS THO WHICH HAS REDUCED
THE OVERALL THREAT FOR FLASH FLOODING FROM RAIN ON SNOW
PACK. HOWEVER THERE APPEARS TO BE SOME REDEVELOPMENT OF STORMS
OFF THE HIGH PEAKS IN CO AND WY MOVING NORTH. SO EXPECT THE
POSSIBILITY OF MODERATE TO HEAVY RAIN TO CONTINUE FROM THIS
ACTIVITY THROUGH THE EARLY EVENING. IN ADDITION...CONVECTION IS
DEVELOPING OVER THE NORTHERN LARAMIE RANGE AT THIS HOUR AS MOIST
SOUTHEAST FLOW CONVERGES ON THE MOUNTAINS. SO...WILL CONTINUE TO
SEE POTENTIAL FOR FLASH FLOODING IN THESE MOUNTAINS THROUGH THIS
EVENING...AND WILL LEAVE THE FLASH FLOOD WATCH AS IS. THE FLASH
FLOOD THREAT FURTHER EAST CONTINUES TO LOOK MARGINAL AND ISOLATED
WITH LACK OF SIGNIFICANT LLVL FORCING OTHER THAN UPSLOPE FLOW.
SHOWERS AND STORMS WILL DIMINISH OVERNIGHT AS MIDLEVEL ENERGY
DEPARTS TO THE NORTHEAST. MOIST SOUTHEASTERLY LLVL FLOW WILL REMAIN
IN PLACE ACROSS THE EASTERN PLAINS...AND MODELS SHOW BOUNDARY LAYER
HUMIDITIES APPROACH 100 PERCENT TONIGHT. ADDED IN PATCHY AREAS OF
FOG TO THIS AREA FOR MUCH OF THE NIGHT...WITH THE HIGHEST LIKELIHOOD
OVER THE CHEYENNE RIDGE AND WITHIN THE NORTH PLATTE RIVER VALLEY.
THE UPPER LOW WILL SLOWLY MOVE INTO THE FOUR CORNERS REGION ON
SATURDAY...WITH ANOTHER MIDLEVEL SHORTWAVE APPROACHING THE CWA FROM
THE SOUTH. RINSE REPEAT...EXPECT ANOTHER CHANCE FOR SHOWERS AND
THUNDERSTORMS LATE SATURDAY AFTERNOON AND EVENING FOR MUCH OF THE
CWA...ESPECIALLY THE MOUNTAINS. WITH WEAK FLOW REMAINING
OVERHEAD...EXPECT SLOW MOVING STORMS DRIVEN BY TERRAIN FEATURES AND
OUTFLOW BOUNDARIES SIMILAR TO TODAY. INSTABILITY OVER THE
MOUNTAINS LOOKS TO BE SLIGHTLY LESS THAN TODAY THO AS A POCKET OF
WARMER MIDLEVEL TEMPS IS PROGGED TO MOVE OVERHEAD...SO INTENSITY
OF ACTIVITY SHOULD BE SLIGHTLY LESS BUT NOT BY MUCH. LOOKING AT
QPF AGAIN OF A COUPLE TENTHS TO ONE HALF INCH OVER THE MOUNTAINS
THROUGH THE AFTERNOON AND EVENING...WITH LESS OVER THE PLAINS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 441 PM MDT FRI MAY 23 2014
GFS AND ECMWF MODELS ARE IN FAIR AGREEMENT TAKING THE PERSISTENT
UPPER LOW OVER THE 4 CORNERS REGION ON SUNDAY SLOWLY EAST INTO THE
SOUTHERN PLAINS BY TUESDAY. A NARROW RIDGE INDUCED BETWEEN THE
UPPER LOW OVER OKLAHOMA AND THE NEXT UPPER LOW SWINGING DOWN THE
PACIFIC NORTHWEST WILL GRADUALLY MOVE ACROSS SOUTHEASTERN WYOMING
AND WESTERN NEBRASKA TUESDAY INTO WEDNESDAY. WE THEN EXPECT TO SEE A
RETURN OF SOUTHWESTERLY FLOW ALOFT THURSDAY INTO NEXT FRIDAY AS THE
NEXT UPPER TROUGH WORKS SLOWLY EAST ACROSS CALIFORNIA AND NEVADA.
WITH THE ACTIVE UPPER FLOW PATTERN ON THE NORTHEAST SIDE OF THE
UPPER LOW CONTINUING SUNDAY AND MONDAY...WE WILL KEEP HIGHER POPS
GOING SUNDAY INTO MONDAY...WITH A DOWNWARD TREND ON POPS TUESDAY AND
WEDNESDAY WITH UPPER RIDGING ALOFT (WE MAY STILL SEE SOME ISOLATED
AFTERNOON STORMS IN THE MOUNTAINS). POPS TREND BACK UP AGAIN BY
LATE NEXT WEEK AS WE SEE AN INCREASE IN SHORTWAVE ENERGY ALOFT WITH
MAINLY DIURNAL SLIGHT CHANCE/CHANCE POPS ADVERTISED FOR
AFTERNOON/EVENING STORMS. TEMPERATURES WILL WARM-UP QUITE A BIT OUT
EAST ON THE PLAINS WITH DAYTIME HIGHS IN THE LOWER TO MIDDLE 80S
MID-WEEK. IN THE WEST...HIGHER ELEVATIONS WILL SEE HIGHS IN THE MID
50S BY THE MIDDLE OF NEXT WEEK...AND OVERNIGHT LOWS AROUND 40. WE
KEPT THE FLASH FLOOD WATCHES AND FLOOD WATCHES GOING SUNDAY INTO
MONDAY OUT WEST IN THE SNOWY...SIERRA MADRE...AND NORTHERN LARAMIE
MOUNTAIN RANGES INCLUDING NEARBY RIVER BASINS DUE TO WARM
TEMPERATURES (SNOWMELT) COMBINED WITH THE POTENTIAL FOR HEAVY RAIN
ON THE SNOWPACK. PLEASE SEE HYDROLOGIC DISCUSSION IN THIS PRODUCT
FOR MORE DETAILED ANALYSIS ON THE FLOOD/FLASH FLOOD POTENTIAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY AFTERNOON)
ISSUED AT 615 PM MDT FRI MAY 23 2014
THE MAIN CONCERN WITH THIS FORECAST PACKAGE WILL BE THE POTENTIAL
FOR LIFR/IFR CEILINGS TONIGHT AT AIA AND SNY.
LATEST RADAR LOOP WAS SHOWING THE BULK OF THE SHOWERS OCCURRING
ACROSS THE WESTERN HALF OF THE FORECAST AREA MAINLY AROUND RWL TAF SITE.
THESE SHOWERS WILL CONTINUE TO FESTER THROUGH SUNSET BEFORE
DISSIPATING. THE NEXT CONCERN TONIGHT WILL BE HOW MUCH THE LOW
CLOUDS IN THE PANHANDLE ADVECT NORTHWEST. CURRENT CEILINGS AT
OGALLALA ARE AROUND 1KFT. SURFACE FLOW IS CURRENTLY SOUTHEAST AND
THIS TREND SHOULD CONTINUE THROUGH MUCH OF THE NIGHT. HRRR IS
SHOWING CEILINGS LOWERING TO THE IFR/LIFR CATEGORY MAINLY AFTER
04Z BEGINNING AT THE SNY TAF SITE AND SPREADING TOWARDS AIA BY
06Z. IF THESE LOWER CEILINGS CAN PUSH EVEN FURTHER WEST...FOG MAY
SETTLE IN ABOVE ELEVATIONS ABOVE 5KFT. THIS MAY OCCUR AT CYS AS
WELL AS THE SOUTHERLY FLOW DEVELOPS AND CREATES UPSLOPE FLOW ALONG
THE CHEYENNE RIDGE. THE CEILINGS SHOULD BEGIN TO LIFT TOWARDS
DAYBREAK AS THE FLOW TURNS MORE TO THE SOUTH/SOUTHWEST IN RESPONSE
TO THE UPPER LEVEL TROF EDGING EASTWARD.
&&
.FIRE WEATHER...
ISSUED AT 441 PM MDT FRI MAY 23 2014
FIRE CONCERNS WILL BE MINIMAL THROUGH THE HOLIDAY WEEKEND AS A MOIST
AIR MASS COMBINES WITH FUELS THAT ARE IN GREEN-UP. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED ALONG AND EAST
OF THE LARAMIE RANGE MOST DAYS...WITH VERY GOOD CHANCES FOR WETTING
RAINS. A MORE WIDESPREAD RAIN EVENT SATURDAY NIGHT AND ESPECIALLY
SUNDAY WILL CONTINUE TO SUPPRESS FIRE WEATHER CONCERNS FOR THE
DISTRICT. WARMER AND DRIER WEATHER IS ANTICIPATED TO RETURN FOR
THE FIRST HALF OF NEXT WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR WYZ103-112-114.
FLOOD WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON FOR
WYZ105-109-110-113-115.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...GARMON
AVIATION...REC
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
230 AM MST SAT MAY 24 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE MOVING EAST ACROSS THE DESERT
SOUTHWEST THIS WEEKEND. A SLIGHT CHANCE OF THUNDERSTORMS WILL BE
LIMITED MAINLY TO THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA THIS
AFTERNOON AND EVENING. ABOVE NORMAL TEMPERATURES WILL RETURN TO THE
REGION EARLY NEXT WEEK AS HIGH PRESSURE BECOMES REESTABLISHED TO OUR
SOUTH AND EAST.
&&
.DISCUSSION...
ERSTWHILE CUTOFF LOW CENTERED ACROSS CENTRAL AZ CONTINUES TO SLIDE
SLOWLY EASTWARD THIS MORNING. GFS AND ECMWF INDICATE THAT VORTICES
EMBEDDED WITHIN THE LARGER CYCLONIC CIRCULATION WILL CONTINUE TO
WEAKEN TODAY AS THE LOW FILLS AND LIFTS NORTHEASTWARD.
CONSEQUENTLY...FORCING FOR ASCENT WILL NOT BE QUITE AS STRONG AND
WILL BE CONCENTRATED WELL TO OUR EAST. NEVERTHELESS...MOISTURE
WRAPPING AROUND THE LOW WILL BE SUFFICIENT FOR ISOLATED
MOUNTAIN-BASED CONVECTION...MAINLY FOCUSED ACROSS NORTHEASTERN AZ.
LOCAL HI-RESOLUTION WRFS SUGGEST A FEW CELLS MAY WORK THEIR WAY INTO
THE PHOENIX AREA THIS AFTERNOON...THOUGH THIS IS GENERALLY NOT
SUPPORTED BY MOST OTHER GLOBAL AND CONVECTIVE-ALLOWING MODELS.
LATEST RUNS OF THE HRRR ARE ALSO NOT AS PROMISING FOR PRECIPITATION.
FORECAST POPS WERE LOWERED SLIGHTLY TO AROUND 10-15 PERCENT FOR THE
PHOENIX AREA BUT REMAIN AS HIGH AS 35 PERCENT ACROSS FAR EASTERN
GILA COUNTY.
AFOREMENTIONED UPPER LOW WILL BE LOCATED ACROSS SOUTHERN CO SUNDAY.
IN ITS WAKE...ISOLATED SHOWERS WILL REMAIN A THREAT ACROSS EASTERN
AZ. HOWEVER...FURTHER WEST A SUBSIDENT NORTHWESTERLY FLOW WILL
BECOME ESTABLISHED ACROSS CENTRAL AZ AND FORECAST POPS WERE LOWERED
TO AROUND 5 PERCENT FOR THE PHOENIX AREA. MEANWHILE...TEMPERATURES
WILL BE AROUND 5 DEGREES WARMER THAN THOSE OBSERVED SATURDAY.
WARMING TREND WILL CONTINUE THROUGH AT LEAST MIDWEEK AS A DRY
SOUTHWESTERLY FLOW DEVELOPS BETWEEN AN AREA OF LOW PRESSURE ACROSS
THE PACIFIC NORTHWEST AND A RIDGE ACROSS NORTHERN MEXICO. LATEST
GUIDANCE HAS TRENDED WARMER AND THIS IS REFLECTED IN THE
FORECAST...THOUGH TEMPERATURES WILL REMAIN WELL BELOW RECORDS.
WARMEST DAY LOOKS TO BE WEDNESDAY WITH HIGH TEMPERATURES REACHING
AROUND 106 DEGREES FOR PHOENIX...YUMA AND EL CENTRO. LATE NEXT
WEEK...GFS/ECMWF HINT AT SOME WEAK MOISTURE TRANSPORT FROM THE
EASTERN PACIFIC WHICH WOULD SUGGEST SOMEWHAT COOLER CONDITIONS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
UPPER LEVEL LOW WILL SLOWLY SHIFT EAST ACROSS AZ INTO NM DURING THE
PERIOD. SCT TO BKN CLOUD DECKS AOA 10KFT WILL GRADUALLY THIN OUT
BECOMING FEW TO SCT ACROSS THE LOWER DESERTS BY 12Z SATURDAY. SOME
LOCAL GUSTINESS REMAINS DUE TO EARLIER DECAYING OUTFLOWS...BUT
EXPECT SURFACE WINDS 10-12KT TO DIMINISH BY 07Z...AND REMAIN LIGHT
OVERNIGHT AT ALL TERMINALS THROUGH 19Z SATURDAY. SUFFICIENT
MOISTURE/INSTABILITY ASSOCIATED WITH THE UPPER LEVEL LOW WARRANTS
KEEPING A SLIGHT CHANCE OF THUNDERSTORMS ACROSS S-CENTRAL AZ
SATURDAY AFTERNOON/EVENING...MAINLY OVER THE HIGHER TERRAIN N AND E
OF PHOENIX. THUNDERSTORMS THAT FORM WILL HAVE THE POTENTIAL TO
PRODUCE OUTFLOW WINDS OF 40 KT AND BLOWING DUST/REDUCED VISIBILITY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
SLIGHT CHANCE FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL REMAIN OVER SOUTHERN GILA COUNTY AND AREAS WELL NORTH AND EAST
OF PHOENIX THROUGH MONDAY. WETTING RAINS ARE NOT LIKELY...WITH
STRONG GUSTY OUTFLOW WINDS AND LIGHTNING REMAINING THE PRIMARY
THREAT WITH STORM DEVELOPMENT. THE BEST MOISTURE AND INSTABILITY
PARAMETERS GREATLY DROP BY TUESDAY THROUGH THE WEEK...AS A RIDGE
BUILDS IN PLACE WITH WARMING AND DRYING CONDITIONS. WINDS WILL BE
MOSTLY CALM...EXCEPT IN AND AROUND THUNDERSTORM DEVELOPMENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION....MEYERS
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1032 PM PDT FRI MAY 23 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE WILL BUILD OVER THE AREA THROUGH
THE HOLIDAY WEEKEND. WARMER TEMPERATURES CAN BE EXPECTED INLAND BUT NIGHT
AND MORNING LOW CLOUDS WITH PATCHY FOG CAN BE EXPECTED ALONG THE
COAST FOR THE NEXT SEVERAL NIGHTS. TEMPERATURES WILL COOL TO NEAR
NORMAL EARLY NEXT WEEK.
&&
.DISCUSSION...AS OF 8:50 PM PDT FRIDAY...HIGH PRESSURE CONTINUES
TO BUILD OVER THE EASTERN PACIFIC AS AN UPPER LOW SPINNING OVER
SOUTHERN CALIFORNIA SHOOTS EASTWARD. ABOVE NORMAL TEMPERATURES
ARE EXPECTED THROUGH THE HOLIDAY WEEKEND AS HIGH PRESSURE BUILDS
AT THE SURFACE AND ALOFT. 850 MB TEMPS ARE FORECAST TO GRADUALLY
INCREASE THROUGH THE WEEKEND...PEAKING ON SUNDAY AROUND 20 DEGREES
C. MEANWHILE 500 MB HEIGHTS WILL ALSO INCREASE WITH HEIGHTS ALSO
PEAKING ON SUNDAY AT AROUND 585 DAM. TEMPERATURES OVER THE WEEKEND
ARE FORECAST TO REACH INTO THE 60S AND 70S ALONG THE COAST AND
INTO THE 80S TO MID 90S INLAND. THE WARMEST INLAND LOCATIONS MAY
TOP OUT IN THE UPPER 90S ON SUNDAY.
CURRENT SATELLITE IMAGERY IS MAKING IT DIFFICULT TO SEE WHAT IS
HAPPENING AT THE SURFACE. HOWEVER BEFORE THE UPPER CLOUDS MOVED IN
AND HAMPERED OUR VIEW WE SAW SIGNIFICANT EROSION OF THE STRATUS
DECK ALONG THE COAST. THE LATEST RUN OF THE HRRR MODEL APPEARS TO
HAVE THE BEST HANDLE ON THE CURRENT SITUATION WHICH SHOWS STRATUS
RAPIDLY ERODING FROM THE MONTEREY COUNTY COAST WITH PATCHY LOW
CLOUDS REMAINING ONLY IN THE MONTEREY BAY. THE HRRR FORECAST
STRATUS TO RETURN TO THE NORTH COAST LATE TONIGHT...SPREADING
SOUTH THROUGH THE REMAINDER OF THE MORNING. THE FORECAST HAS BEEN
UPDATED TO REFLECT THIS CHANGE. CONFIDENCE IS LOW WITH RESPECT TO
STRATUS INTRUSION OVER THE NORTH BAY. WITH THE LATE ONSET OF THE
STRATUS ALONG THE COAST AND THE COMPRESSION OF THE MARINE LAYER
DUE TO BUILDING HIGH PRESSURE WE ANTICIPATE LESS INLAND STRATUS
INTRUSION THAN PREVIOUS NIGHTS.
FROM PREVIOUS DISCUSSION...
NORTHERLY PRESSURE GRADIENT RAMPS UP ON MONDAY AS HIGH PRESSURE
WEAKENS AND A TROUGH APPROACHES FROM THE NORTHWEST. THE INCREASED
GRADIENT/FLOW MAY BE STRONG ENOUGH TO DISRUPT THE MARINE LAYER AND
KEEP CLOUDS MAINLY OVER THE COASTAL WATERS. EITHER WAY...MEMORIAL
DAY IS SHAPING UP TO BE PLEASANT WITH NEAR NORMAL TEMPS ALONG THE
COAST AND SLIGHTLY ABOVE NORMAL TEMPS INLAND. IN OTHER
WORDS...JUST A TAD COOLER THAN SUNDAY.
LONG TERM(TUESDAY-FRIDAY)...
MUCH OF THE PATTERN FOR THE LONG TERM WILL BE A BROAD UPPER LEVEL
TROUGH OVER THE WEST COAST. THE TROUGH WILL KEEP THE MARINE LAYER
MIXED OUT. MORE SUNSHINE WILL BE SEEN...BUT THE TROUGH AND COOLER
AIRMASS WILL BRING TEMPERATURES CLOSER TO NORMAL.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...MODERATE NORTHERLY FLOW
PUSHED STRATUS FIELD SOUTH...WITH LOW CLOUDS ONLY IMPACTING THE
MONTEREY BAY. CURRENT FORECAST MUCH MORE OPTIMISTIC COMPARED TO
PREVIOUS FORECAST. HIGH LEVEL CLOUDS MOVED OVER THE AREA...CURRENT
THINKING IS THAT THIS MAY PREVENT ANY LOW CLOUDS/FOG TO FORM IN
THE NORTH BAY...SO IT WAS COMPLETELY REMOVED FROM THE FORECAST.
LOW CLOUDS MAY STILL FORM ALONG SAN MATEO COAST...HOWEVER A
UNIFORM FIELD IS UNLIKELY TO IMPACT THE SF BAY. THE HRRR WAS THE
MAIN MODELS USED FOR THE FORECAST AS IT IS THE ONLY MODEL WHICH
SEEMED TO HAVE A GRASP ON THE CURRENT SITUATION.
VICINITY OF KSFO...PATCHY MVFR CIGS POSSIBLE BETWEEN 10Z AND 17Z.
LOW CONFIDENCE. MODERATE TO OCCASIONALLY STRONG ONSHORE WINDS
SATURDAY AFTERNOON...WITH GUSTS TO 30 KT AFTER 22Z. MODERATE
CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WILL BECOME IFR AROUND
10Z. LOW TO MODERATE CONFIDENCE.
&&
.MARINE...AS OF 8:10 PM PDT FRIDAY...NORTHERLY WINDS WILL INCREASE
THROUGH THE WEEKEND THROUGH MOST OF NEXT WEEK AS SURFACE HIGH
PRESSURE STRENGTHENS OVER THE EASTERN PACIFIC. THESE WINDS WILL
GENERATE STEEP FRESH SWELLS WHICH WILL BE PRESENT OVER THE WATERS
THROUGH AT LEAST FRIDAY OF NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT ARENA TO PT REYES 10-60 NM
SCA...PT REYES TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PINOS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: CW
AVIATION/MARINE: RILEY
VISIT US AT WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1141 PM MDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 1134 PM MDT FRI MAY 23 2014
LOADED IN LATEST OBSERVATIONS AND ADJUSTED POPS TO REFLECT CURRENT
RADAR TRENDS. LW
UPDATE ISSUED AT 541 PM MDT FRI MAY 23 2014
LOADED LATEST OBSERVATIONS INTO SHORT TERM FORECAST GRIDS. NO
OTHER UPDATES TO FORECAST AT THIS TIME. LW
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 332 PM MDT FRI MAY 23 2014
CURRENTLY...CONVECTION RATHER SPARSE ACROSS SOUTHERN COLORADO SO FAR
THIS AFTERNOON...THOUGH AREA OF MORE VIGOROUS TSRA WASN`T TOO FAR
AWAY OVER NRN NM. AIR MASS OVER THE REGION REMAINS MODERATELY
UNSTABLE...AND EXPECT AN INCREASE IN STORMS MOST AREAS THROUGH THE
REMAINDER OF THE AFTERNOON...AS SEVERAL WEAK BOUNDARIES EVIDENT IN
KPUX RADAR DATA MAY CONVERGE ACROSS PUEBLO/EL PASO COUNTIES 21Z-
23Z...WHICH COULD FORCE SOME NEW CONVECTION. MESOSCALE
MODELS...INCLUDING THE LATEST HRRR SUPPORT THE IDEA OF INCREASING
TSRA OVER THE PLAINS THROUGH EARLY EVENING AS WELL. CONVECTION WILL
GRADUALLY WANE BY MIDNIGHT...THOUGH WITH MODELS HINTING AT OVERNIGHT
MCS ACROSS NRN NM...WILL KEEP SOME LOW POPS GOING DURING THE
NIGHT...MAINLY ACROSS SOUTHERN ZONES.
MESOSCALE DETAILS WILL LIKELY DRIVE CONVECTION ON SATURDAY...AS SOME
SORT OF WEAKENING MCS WILL BE MOVING OUT OF NERN NM/TX PANH INTO THE
SOUTHEAST PLAINS DURING THE MORNING. DEPENDING ON STRENGTH OF
MCS...MUCH OF AREA ALONG AND EAST OF THE MOUNTAINS MAY SEE SOME
FAIRLY HEALTHY SUBSIDENCE ON THE BACK SIDE OF THE SYSTEM...WHICH
WOULD LIMIT TSRA CHANCES. STILL...WITH MODERATE INSTABILITY COVERING
MOST OF THE AREA...TOUGH TO RULE OUT STORMS JUST ABOUT ANYWHERE
DURING THE AFTERNOON. BEST PRECIP COVERAGE MAY END UP OVER THE
SOUTHWEST MOUNTAINS...WHERE STRONG DYNAMIC LIFT FROM THE UPPER LOW
COMES INTO PLAY DURING THE LATE AFTERNOON. SEVERE THREAT LOOKS LOW
ONCE AGAIN...AS DEEPER INSTABILITY AND STRONGER WIND SHEAR REMAIN TO
THE SOUTH OVER WRN TX. MAX TEMPS SHOULD STAY RELATIVELY
UNCHANGED...WITH READINGS REMAINING BELOW SEASONAL AVERAGES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 332 PM MDT FRI MAY 23 2014
SATURDAY NIGHT THROUGH TUESDAY...A VERY UNSETTLED PATTERN IN PLACE
OVER THE HOLIDAY WEEKEND...AND THE GFS...NAM AND EC MODELS ALL SEEM
TO AGREE ON THIS. THE UPPER LOW CURRENTLY OVER SOUTHWESTERN AZ IS
EXPECTED TO SLOWLY MEANDER ALONG THE CO/NM STATE LINE SAT NIGHT
THROUGH MON...BEFORE EXITING TO THE EAST ACROSS THE OK AND TX
PANHANDLES ON TUE. A COUPLE OF THINGS TO NOTE WITH THIS SYSTEM. THE
SLOW MOVEMENT AND THE EXPECTED PLACEMENT OF THE LOW MEANS THAT THERE
IS THE POTENTIAL FOR SOME HEAVY RAINFALL IN PLACES. MODELS ALSO
INDICATE A POSSIBLE DRY SLOT FOR SUNDAY ACROSS THE PLAINS. WHERE THE
HEAVY RAINFALL OCCURS...AND WHERE AND WHEN THE DRY SLOT WILL
HAPPEN...IS VERY DIFFICULT TO PREDICT AT THIS TIME.
THEREFORE...BLANKETED MOSTLY CLOUDY TO OVERCAST SKIES FOR THE
FORECAST AREA FOR MUCH OF THE WEEKEND...AND WENT WITH AT LEAST
ISOLATED POPS FOR MUCH OF THE AREA AT ALL TIMES. MODELS INDICATE THE
DRY SLOT WILL OCCUR SUNDAY OVER THE PLAINS...SO LESSENED SKY COVER
AND LOWERED POPS THERE DURING THAT TIME FRAME.
OTHERWISE...CONVECTION WILL OCCUR IN BANDS AND EXACT AMOUNTS AND
PLACEMENT ARE IMPOSSIBLE AT THIS TIME. AS FOR TEMPS...SHOULD BE
FAIRLY WARM WITH MAX TEMPS NEAR 80 F FOR THE PLAINS EACH
DAY...THOUGH ONGOING MAX TEMP FOR TUE WILL MOST LIKELY HAVE TO BE
COOLED. AREA BURN SCARS WILL NEED TO BE MONITORED CLOSELY EACH DAY
OVER THE HOLIDAY WEEKEND.
WEDNESDAY THROUGH FRIDAY...EXTENDED MODELS INDICATE THAT THE UPPER
LOW WILL HAVE FINALLY MOVED EAST OF THE AREA AND OUT OF COLORADO BY
TUE EVE...WITH RIDGING DEVELOPING ACROSS THE DESERT SW FOR THE
SECOND HALF OF THE WEEK. THE GFS PAINTS A VERY WET PICTURE...WHILE
THE EC IS LEANING TOWARDS A MORE PROBABLE SOLUTION OF DIURNAL MT
CONVECTION AND PREDOMINANTLY DRY ELSEWHERE. THEREFORE...AMENDED THE
EXTENDED PROCEDURE POP GRIDS TO SHOW ISOLATED TO LOW END SCATTERED
POPS OVER THE MTS AND ADJACENT PLAINS EACH AFTN AND EVE...THEN DRY
WITH CLEARING SKIES OVERNIGHT. SEASONABLE TEMPS ARE FORECAST...WITH
MAX TEMPS IN THE 80S FOR THE PLAINS AND 70S FOR THE HIGH VALLEYS.
MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1134 PM MDT FRI MAY 23 2014
ROUND OF INTENSE SHOWERS AND THUNDERSTORMS WINDING DOWN FOR THIS
EVENING. STILL SOME MVFR/IFR/LIFR CONDITIONS POSSIBLE WITH ANY
LINGERING SHOWERS OR THUNDERSTORMS THROUGH THE NIGHT. A NEW ROUND
OF CONVECTION IS EXPECTED TO DEVELOP FOR TOMORROW AFTERNOON AND
EVENING AS WE REMAIN UNDER MOIST SOUTHERLY FLOW AROUND LARGE
UPPER LOW PRESSURE AREA OVER THE SOUTHWEST US. EXPECT MORE
SCATTERED TO NUMEROUS MVFR/IFR/LIFR CONDITIONS ASSOCIATED WITH
THIS ACTIVITY BEGINNING AFTER 17Z TOMORROW. HEAVY RAIN...1 INCH
DIAMETER HAIL...LIGHTNING AND ERRATIC OUTFLOW WINDS ALL POSSIBLE
WITH CONVECTION.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...LW
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...LW
AREA FORECAST DISCUSSION
NWS ALBANY NY
128 AM EDT SAT MAY 24 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE REGION OVERNIGHT. ANOTHER DISTURBANCE ROTATING
AROUND THE UPPER LEVEL LOW WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO EASTERN NEW YORK AND WESTERN NEW ENGLAND TOMORROW
WITH LOCALLY HEAVY DOWNPOURS POSSIBLE. THE WEATHER WILL GRADUALLY
IMPROVE SUNDAY INTO MEMORIAL DAY AS HIGH PRESSURE BUILDS IN WITH
SEASONABLE TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM EDT...RADAR INDICATED THAT ACTIVITY HAS DIMINISHED BUT
NOT GONE ENTIRELY AWAY. THE SHORT WAVE...RESPONSIBLE FOR FRIDAY/S
ACTIVITY (AWAY FROM THE IMMEDIATE CAPITAL DISTRICT) WAS MOVING TO
THE SOUTH AND EAST. HOWEVER...THERE WAS STILL PLENTY OF MOISTURE
ROTATING IN A CYCLONIC FLOW...KEEP THAT POSSIBILITY OF ISOLATED
SHOWERS AND OR DRIZZLE (WHICH THERE HAS BEEN SOME OFF TOO). SO FOR
THIS UPDATE...WILL LOWER POPS TO ISOLATED...BUT ADD THE PATCHY
DRIZZLE.
FOR THIS UPDATE...MINOR HOURLY RE-TOOLING OF THE GRIDS...LOWERED THE
POPS TO ISOLATED AND ADDED PATCHY DRIZZLE.
THE LATEST 3-KM HRRR JUSTIFIES TRENDING TO ISOLATED SHOWERS...AT IT
INDICATED COVERAGE NOT GOING COMPLETELY AWAY...BUT DIMINISHING A
LITTLE IN AREAS. IT WAS COOL IN THE AIR MASS WITH TEMPS MAINLY IN
THE UPPER 40S TO MID 50S. SOME PATCHY FOG WAS ADDED THE FCST IN THE
AREAS WHERE THE RAINFALL OCCURRED TODAY...MAINLY NORTH AND EAST OF
THE CAPITAL DISTRICT AS WELL AS SOUTH OF THE CAPITAL DISTRICT.
LOWS ACROSS THE REGION ARE EXPECTED TO BE IN THE MID 40S TO MID
50S WITH LIGHT NORTH TO NORTHWEST WINDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
SATURDAY INTO SUNDAY THE FA WILL CONTINUE TO BE UNDER CYCLONIC
FLOW. THE FA WILL ACTUALLY BE UNDER NORTHWEST FLOW POSITIONED
BETWEEN THE UPPER LOW OVER THE CANADIAN MARITIMES AND RIDGING OVER
THE CENTRAL CONUS. UNFORTUNATELY OUR AREA WILL STILL BE INFLUENCED
BY THE UPPER LEVEL TROUGH WHICH PUTS OUR AREA SANDWICHED BETWEEN
THIS TROUGH AND HIGH PRESSURE OVER THE CENTRAL GREAT LAKES. BY
SUNDAY THE TROUGH AXIS SHOULD BE TO OUR EAST SUCH THAT HIGH
PRESSURE WILL START TO NOSE IN FROM THE OHIO VALLEY.
EXPECT HIGHS ON SATURDAY TO BE IN THE MID 60S TO LOWER 70S WITH
LOWS SATURDAY NIGHT IN THE 40S TO AROUND 50 AND HIGHS ON SUNDAY IN
THE MID TO UPPER 70S.
SUNDAY NIGHT AND MONDAY LOOK TO BE MAINLY DRY AS THE RIDGE OF HIGH
PRESSURE SETTLES ACROSS OUR REGION. EXPECT LOWS SUNDAY NIGHT TO BE
IN THE MID 40S TO LOWER 50S AND HIGHS ON MONDAY IN THE MID 70S TO
MID 80S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MUCH OF THE LONG TERM PORTION OF THE FORECAST WILL FEATURE MEAN
MID/UPPER LEVEL TROUGHING OFF THE NORTHEAST COAST...WITH RIDGING
BUILDING OVER THE CENTRAL CONUS. THIS WILL KEEP OUR REGION IN A
GENERAL NORTHWEST FLOW...WITH SEVERAL RELATIVELY FAST MOVING
DISTURBANCES PASSING THROUGH THIS FLOW. ONE SUCH DISTURBANCE IS
EXPECTED TO PASS THROUGH MON NT INTO TUE OR TUE NT...THEN AGAIN
TOWARD THE THU-FRI TIME FRAME.
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MON NT THROUGH TUE
EVENING WITH THE PASSAGE OF THE FIRST DISTURBANCE...AND ASSOCIATED
SFC COLD FRONT. ADDITIONAL SHOWERS MAY OCCUR BY LATE THU OR FRI WITH
THE SECOND FEATURE.
HERE ARE SOME MORE SPECIFICS FOR THE LONG TERM PERIOD...
MON NT-TUE NT...THE INITIAL DISTURBANCE PASSES THROUGH...WITH A SFC
COLD FRONT SETTLING SOUTHWARD ACROSS THE REGION. IT IS POSSIBLE THAT
A WAVE OR WAVES DEVELOP ALONG THIS SOUTHWARD MOVING FRONT. WILL
INDICATE SCATTERED SHOWERS AND THUNDERSTORMS FOR THIS TIME PERIOD.
THE 12Z/23 ECMWF SUGGESTS SOME RATHER STRONG MID/UPPER LEVEL
DYNAMICS OCCUR WITH THIS FEATURE...SO SOME STRONGER THUNDERSTORMS
COULD OCCUR DEPENDING ON TIME OF DAY/AMT OF DIURNAL HEATING. TEMPS
SHOULD FALL INTO THE 50S TO LOWER 60S MON NT...WITH MAINLY 70S
EXPECTED FOR TUE...ALTHOUGH SOME LOWER 80S COULD OCCUR IN VALLEY
AREAS IF THE AFOREMENTIONED FRONTAL BOUNDARY MOVES SLOWER THAN
INDICATED. TUE NT/WED AM MINS SHOULD FALL INTO THE 50S.
WED-THU NT...AT THIS TIME...BASED ON CONSENSUS OF LONG TERM MODELS
AND THEIR ENSEMBLES REGARDING THE TIMING OF FAST MOVING FEATURES
EMBEDDED IN THE NORTHWEST FLOW...IT APPEARS THAT HIGH PRESSURE
SHOULD PROVIDE GENERALLY FAIR CONDITIONS DURING THIS TIME
FRAME...ALONG WITH SLIGHTLY COOLER TEMPS. EXPECT WED MAX TEMPS TO
REACH THE LOWER 70S IN VALLEY...AND MAINLY 60S ACROSS HIGHER
ELEVATIONS. WED NT/THU AM MINS SHOULD FALL INTO THE LOWER 50S IN
VALLEYS...WITH 40S ACROSS MOST HIGHER ELEVATIONS. HOWEVER...EVEN
COOLER MIN TEMPS COULD OCCUR. FOR THU...MAX TEMPS SHOULD REACH THE
MID 70S IN VALLEYS...AND MID 60S TO AROUND 70 ACROSS HIGHER
ELEVATIONS...WITH OVERNIGHT MIN TEMPS FOR THU NT/FRI AM FALLING INTO
THE LOWER/MID 50S IN VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
FRI...ANOTHER DISTURBANCE MAY APPROACH IN THE NORTHWEST FLOW.
FRONTAL SYSTEMS ASSOCIATED WITH THIS NEXT FEATURE MAY TRIGGER SOME
SHOWERS BY FRI AFTERNOON. TEMPS SHOULD WARM INTO THE 70S TO LOWER
80S...WITH OVERNIGHT LOW TEMPS IN THE 50S TO AROUND 60.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AN UPPER LEVEL LOW WILL CONTINUE TO IMPACT THE REGION THROUGH
TOMORROW WITH MULTIPLE DISTURBANCES ROTATING AROUND IT.
CEILINGS ARE QUITE VARIABLE WITH VFR AT KALB AND KPOU...MVFR AT KGFL
AND IFR AT KPSF. THERE ARE A FEW SPRINKLES AND ISOLATED SHOWERS
AROUND KGFL...KALB AND KPSF BUT THE INTENSITY IS LIGHT AND COVERAGE
IS ISOLATED SO KEEPING VCSH THROUGH THE MORNING. CEILINGS SHOULD
LOWER THROUGH SUNRISE TO MVFR OR AT LEAST BE INTERMITTENT MVFR AT
KALB AND KPOU...WHILE STAYING MVFR AT KGFL AND HOVERING BETWEEN IFR
AND LOW MVFR AT KPSF.
AS THE PAST FEW DAYS...IT WILL TAKE UNTIL THE LATE MORNING FOR THE
EROSION OF THE LOW STRATUS. CIGS ARE EXPECTED TO RISE TO 3.5-4.5
KFT AGL BY THE LATE MORNING. A DISTURBANCE ROTATING AROUND THE
LOW...A SFC TROUGH...WILL FOCUS MORE SHOWERS AND PERHAPS SOME ISOLD
THUNDERSTORMS DURING THE AFTERNOON. ACKNOWLEDGING MORE COVERAGE OF
SHOWERS IN THE AFTERNOON WITH MVFR VISIBILITIES IN SHOWERS. THE
PROBABILITIES WERE TOO LOW TO PLACE IN THE TAFS THIS FAR OUT...AND
WILL BE MONITORED LATER. SHOWERS SHOULD EXIT BY EVENING AND CEILINGS
IMPROVE TO VFR DURING THE LATE AFTERNOON AND EVENING.
THE WINDS WILL BE LIGHT AND VARIABLE THROUGH MOST OF THIS MORNING.
EXPECT THE WINDS TO INCREASE FROM THE N TO NW AT 5-10 KTS DURING THE
LATE MORNING INTO THE AFTERNOON. THE WINDS MAY BE STRONGER...AND
VARIABLE IN DIRECTION IN AND NEAR ANY THUNDERSTORMS. WINDS BECOME
LIGHT AND VARIABLE AGAIN TOMORROW EVENING.
OUTLOOK...
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MEMORIAL DAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY NIGHT TO WEDNESDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA.
&&
.FIRE WEATHER...
DISTURBANCES IN THE UPPER LEVELS WILL CONTINUE TO MOVE OVER THE
REGION THROUGH SUNDAY...TRIGGERING MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS. THE STRONGEST OF THE DISTURBANCES WILL OCCUR THIS
AFTERNOON AND EVENING...WITH THE GREATEST CHANCES FOR STORMS...SOME
OF WHICH COULD CONTAIN LOCALLY HEAVY DOWNPOURS AND SMALL HAIL.
TEMPERATURES ARE EXPECTED TO BECOME SEASONABLY WARM OVER THE
HOLIDAY WEEKEND.
&&
.HYDROLOGY...
DISTURBANCES IN THE UPPER LEVELS WILL CONTINUE TO MOVE OVER THE
REGION THROUGH SUNDAY TRIGGERING MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS. THE STRONGEST OF THE DISTURBANCES WILL OCCUR
THROUGH SATURDAY WITH THE POSSIBILITY OF FLASH FLOODING THROUGH
THIS EVENING. RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE EXPECTED WHERE
THE RAIN DOES OCCUR WITH LOCALLY HIGHER AMOUNTS.
AREAL COVERAGE OF CONVECTION SATURDAY IS NOT EXPECTED TO BE AS
GREAT AS TODAY AND WITH LESSER COVERAGE EXPECTED ON SUNDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...HWJIV/WASULA
SHORT TERM...11
LONG TERM...KL
AVIATION...NAS
FIRE WEATHER...11
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS ALBANY NY
1230 AM EDT SAT MAY 24 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE REGION OVERNIGHT. ANOTHER DISTURBANCE ROTATING
AROUND THE UPPER LEVEL LOW WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO EASTERN NEW YORK AND WESTERN NEW ENGLAND TOMORROW
WITH LOCALLY HEAVY DOWNPOURS POSSIBLE. THE WEATHER WILL GRADUALLY
IMPROVE SUNDAY INTO MEMORIAL DAY AS HIGH PRESSURE BUILDS IN WITH
SEASONABLE TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM EDT...RADAR INDICATED THAT ACTIVITY HAS DIMINISHED BUT
NOT GONE ENTIRELY AWAY. THE SHORT WAVE...RESPONSIBLE FOR FRIDAY/S
ACTIVITY (AWAY FROM THE IMMEDIATE CAPITAL DISTRICT) WAS MOVING TO
THE SOUTH AND EAST. HOWEVER...THERE WAS STILL PLENTY OF MOISTURE
ROTATING IN A CYCLONIC FLOW...KEEP THAT POSSIBILITY OF ISOLATED
SHOWERS AND OR DRIZZLE (WHICH THERE HAS BEEN SOME OFF TOO). SO FOR
THIS UPDATE...WILL LOWER POPS TO ISOLATED...BUT ADD THE PATCHY
DRIZZLE.
FOR THIS UPDATE...MINOR HOURLY RE-TOOLING OF THE GRIDS...LOWERED THE
POPS TO ISOLATED AND ADDED PATCHY DRIZZLE.
THE LATEST 3-KM HRRR JUSTIFIES TRENDING TO ISOLATED SHOWERS...AT IT
INDICATED COVERAGE NOT GOING COMPLETELY AWAY...BUT DIMINISHING A
LITTLE IN AREAS. IT WAS COOL IN THE AIR MASS WITH TEMPS MAINLY IN
THE UPPER 40S TO MID 50S. SOME PATCHY FOG WAS ADDED THE FCST IN THE
AREAS WHERE THE RAINFALL OCCURRED TODAY...MAINLY NORTH AND EAST OF
THE CAPITAL DISTRICT AS WELL AS SOUTH OF THE CAPITAL DISTRICT.
LOWS ACROSS THE REGION ARE EXPECTED TO BE IN THE MID 40S TO MID
50S WITH LIGHT NORTH TO NORTHWEST WINDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
SATURDAY INTO SUNDAY THE FA WILL CONTINUE TO BE UNDER CYCLONIC
FLOW. THE FA WILL ACTUALLY BE UNDER NORTHWEST FLOW POSITIONED
BETWEEN THE UPPER LOW OVER THE CANADIAN MARITIMES AND RIDGING OVER
THE CENTRAL CONUS. UNFORTUNATELY OUR AREA WILL STILL BE INFLUENCED
BY THE UPPER LEVEL TROUGH WHICH PUTS OUR AREA SANDWICHED BETWEEN
THIS TROUGH AND HIGH PRESSURE OVER THE CENTRAL GREAT LAKES. BY
SUNDAY THE TROUGH AXIS SHOULD BE TO OUR EAST SUCH THAT HIGH
PRESSURE WILL START TO NOSE IN FROM THE OHIO VALLEY.
EXPECT HIGHS ON SATURDAY TO BE IN THE MID 60S TO LOWER 70S WITH
LOWS SATURDAY NIGHT IN THE 40S TO AROUND 50 AND HIGHS ON SUNDAY IN
THE MID TO UPPER 70S.
SUNDAY NIGHT AND MONDAY LOOK TO BE MAINLY DRY AS THE RIDGE OF HIGH
PRESSURE SETTLES ACROSS OUR REGION. EXPECT LOWS SUNDAY NIGHT TO BE
IN THE MID 40S TO LOWER 50S AND HIGHS ON MONDAY IN THE MID 70S TO
MID 80S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MUCH OF THE LONG TERM PORTION OF THE FORECAST WILL FEATURE MEAN
MID/UPPER LEVEL TROUGHING OFF THE NORTHEAST COAST...WITH RIDGING
BUILDING OVER THE CENTRAL CONUS. THIS WILL KEEP OUR REGION IN A
GENERAL NORTHWEST FLOW...WITH SEVERAL RELATIVELY FAST MOVING
DISTURBANCES PASSING THROUGH THIS FLOW. ONE SUCH DISTURBANCE IS
EXPECTED TO PASS THROUGH MON NT INTO TUE OR TUE NT...THEN AGAIN
TOWARD THE THU-FRI TIME FRAME.
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MON NT THROUGH TUE
EVENING WITH THE PASSAGE OF THE FIRST DISTURBANCE...AND ASSOCIATED
SFC COLD FRONT. ADDITIONAL SHOWERS MAY OCCUR BY LATE THU OR FRI WITH
THE SECOND FEATURE.
HERE ARE SOME MORE SPECIFICS FOR THE LONG TERM PERIOD...
MON NT-TUE NT...THE INITIAL DISTURBANCE PASSES THROUGH...WITH A SFC
COLD FRONT SETTLING SOUTHWARD ACROSS THE REGION. IT IS POSSIBLE THAT
A WAVE OR WAVES DEVELOP ALONG THIS SOUTHWARD MOVING FRONT. WILL
INDICATE SCATTERED SHOWERS AND THUNDERSTORMS FOR THIS TIME PERIOD.
THE 12Z/23 ECMWF SUGGESTS SOME RATHER STRONG MID/UPPER LEVEL
DYNAMICS OCCUR WITH THIS FEATURE...SO SOME STRONGER THUNDERSTORMS
COULD OCCUR DEPENDING ON TIME OF DAY/AMT OF DIURNAL HEATING. TEMPS
SHOULD FALL INTO THE 50S TO LOWER 60S MON NT...WITH MAINLY 70S
EXPECTED FOR TUE...ALTHOUGH SOME LOWER 80S COULD OCCUR IN VALLEY
AREAS IF THE AFOREMENTIONED FRONTAL BOUNDARY MOVES SLOWER THAN
INDICATED. TUE NT/WED AM MINS SHOULD FALL INTO THE 50S.
WED-THU NT...AT THIS TIME...BASED ON CONSENSUS OF LONG TERM MODELS
AND THEIR ENSEMBLES REGARDING THE TIMING OF FAST MOVING FEATURES
EMBEDDED IN THE NORTHWEST FLOW...IT APPEARS THAT HIGH PRESSURE
SHOULD PROVIDE GENERALLY FAIR CONDITIONS DURING THIS TIME
FRAME...ALONG WITH SLIGHTLY COOLER TEMPS. EXPECT WED MAX TEMPS TO
REACH THE LOWER 70S IN VALLEY...AND MAINLY 60S ACROSS HIGHER
ELEVATIONS. WED NT/THU AM MINS SHOULD FALL INTO THE LOWER 50S IN
VALLEYS...WITH 40S ACROSS MOST HIGHER ELEVATIONS. HOWEVER...EVEN
COOLER MIN TEMPS COULD OCCUR. FOR THU...MAX TEMPS SHOULD REACH THE
MID 70S IN VALLEYS...AND MID 60S TO AROUND 70 ACROSS HIGHER
ELEVATIONS...WITH OVERNIGHT MIN TEMPS FOR THU NT/FRI AM FALLING INTO
THE LOWER/MID 50S IN VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
FRI...ANOTHER DISTURBANCE MAY APPROACH IN THE NORTHWEST FLOW.
FRONTAL SYSTEMS ASSOCIATED WITH THIS NEXT FEATURE MAY TRIGGER SOME
SHOWERS BY FRI AFTERNOON. TEMPS SHOULD WARM INTO THE 70S TO LOWER
80S...WITH OVERNIGHT LOW TEMPS IN THE 50S TO AROUND 60.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AN UPPER LEVEL LOW WILL CONTINUE TO IMPACT THE REGION THROUGH
TOMORROW WITH MULTIPLE DISTURBANCES ROTATING AROUND IT.
VFR/MVFR CIGS WILL CONTINUE TONIGHT INTO THE LATE MORNING TOMORROW
IN THE MOIST AIR MASS WITH A GOOD CHANCE OF SHOWERS PRIOR TO
MIDNIGHT. VSBYS MAY LOWER TO MVFR LEVELS IN THE SHOWERS. SOME LOW
MVFR STRATUS MAY SET UP FOR MOST OF THE TERMINALS TONIGHT. THE ONE
EXCEPTION IS KPSF WHERE SOME IFR CIGS WILL BE POSSIBLE.
AS THE PAST FEW DAYS...IT WILL TAKE UNTIL THE LATE MORNING FOR THE
EROSION OF THE LOW STRATUS. CIGS ARE EXPECTED TO RISE TO 3.5-4.5
KFT AGL BY THE LATE MORNING. A DISTURBANCE ROTATING AROUND THE
LOW...A SFC TROUGH...WILL FOCUS MORE SHOWERS AND PERHAPS SOME ISOLD
THUNDERSTORMS TOMORROW. THE PROBABILITIES WERE TOO LOW TO PLACE IN
THE TAFS THIS FAR OUT...AND WILL BE MONITORED LATER.
THE WINDS WILL BE INITIALLY FROM THE WEST TO NORTH AT LESS THAN 10
KTS EARLY THIS EVENING...AND THEN WILL BECOME LIGHT FROM THE N/NW
AT 5 KTS OR LESS. EXPECT THE WINDS TO INCREASE FROM THE N TO NW AT
5-10 KTS TOMORROW LATE MORNING INTO THE AFTERNOON. THE WINDS MAY
BE STRONGER...AND VARIABLE IN DIRECTION IN AND NEAR ANY
THUNDERSTORMS.
OUTLOOK...
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MEMORIAL DAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY NIGHT TO WEDNESDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA.
&&
.FIRE WEATHER...
DISTURBANCES IN THE UPPER LEVELS WILL CONTINUE TO MOVE OVER THE
REGION THROUGH SUNDAY...TRIGGERING MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS. THE STRONGEST OF THE DISTURBANCES WILL OCCUR THIS
AFTERNOON AND EVENING...WITH THE GREATEST CHANCES FOR STORMS...SOME
OF WHICH COULD CONTAIN LOCALLY HEAVY DOWNPOURS AND SMALL HAIL.
TEMPERATURES ARE EXPECTED TO BECOME SEASONABLY WARM OVER THE
HOLIDAY WEEKEND.
&&
.HYDROLOGY...
DISTURBANCES IN THE UPPER LEVELS WILL CONTINUE TO MOVE OVER THE
REGION THROUGH SUNDAY TRIGGERING MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS. THE STRONGEST OF THE DISTURBANCES WILL OCCUR
THROUGH SATURDAY WITH THE POSSIBILITY OF FLASH FLOODING THROUGH
THIS EVENING. RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE EXPECTED WHERE
THE RAIN DOES OCCUR WITH LOCALLY HIGHER AMOUNTS.
AREAL COVERAGE OF CONVECTION SATURDAY IS NOT EXPECTED TO BE AS
GREAT AS TODAY AND WITH LESSER COVERAGE EXPECTED ON SUNDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...HWJIV/WASULA
SHORT TERM...11
LONG TERM...KL
AVIATION...KL/WASULA
FIRE WEATHER...11
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
425 AM EDT SAT MAY 24 2014
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL
PATTERN FOR LATE MAY IN PLACE ACROSS THE CONUS. LOOKING FROM WEST TO
EAST WE FIND SPLIT FLOW ARRIVING OVER THE PACIFIC COAST WITH ONE
BRANCH RIDING TO THE NORTH INTO A LARGE RIDGE OVER SOUTH-CENTRAL
CANADA...AND THE OTHER BRANCH DROPPING SOUTH IN TO A LARGE CLOSED
UPPER LOW FEATURE OVER THE SOUTHWESTERN STATES. THIS SOUTHERN BRANCH
CONTINUES INTO DOWNSTREAM RIDGING EXTENDING FROM THE GULF OF MEXICO
NORTHWARD OVER THE CENTRAL PLAINS. OUR LOCAL AREA RESIDES UNDER THE
EASTERN SIDE OF THIS RIDGE AXIS. FINALLY AN ENERGETIC TROUGH IS
SLIDING OFF THE NEW ENGLAND/MID ATLANTIC COAST...WITH ALL ITS
ASSOCIATED WEATHER REMAINING WELL TO OUR NORTH AND NORTHEAST.
AT THE SURFACE...A WEAK RIDGE OF HIGH PRESSURE IS ALIGNED ACROSS THE
FL PENINSULA AND GULF OF MEXICO...WHILE A COLD FRONT SLOWLY DROPS
SOUTH ACROSS GA/CAROLINAS. THIS FRONT IS PROGGED TO STALL AND WASH
OUT OVER NORTHERN FLORIDA LATER TODAY. TEMPERATURES ARE SEASONABLE
RANGING FROM THE UPPER 60S TO LOWER 70S INLAND...AND IN THE MIDDLE
70S ALONG THE COAST. PATCHY GROUND FOG HAS BEGUN TO DEVELOP DUE TO
THE SUPPRESSION OF THE RIDGE ALOFT OVER TOP A FAIRLY MOIST BOUNDARY
LAYER. NOT EXPECTING A WIDESPREAD FOG ISSUE THIS MORNING...BUT A FEW
OF THE NORMALLY FOG PRONE AREA MAY SEE A PERIOD OF DENSE FOG FOR
AT LEAST THE FIRST PART OF THE MORNING COMMUTE.
&&
.SHORT TERM (TODAY AND TONIGHT)...
TODAY AND TONIGHT...
585-588DM UPPER LEVEL RIDGING WILL REMAIN IN PLACE OVER THE FLORIDA
PENINSULA THROUGH THE DAYLIGHT HOURS. THE SUPPRESSIVE EFFECTS OF THE
RIDGE ALONG WITH GOOD DIURNAL MIXING WILL RESULT IN ANOTHER HOT DAY
AWAY FROM THE IMMEDIATE COAST. TEMPERATURES INLAND WILL SOAR INTO
THE LOWER TO MIDDLE 90S FOR THE AFTERNOON HOURS. THIS STRONG
TERRESTRIAL HEATING WILL FORCE A DECENT SEA-BREEZE CIRCULATION
(SIMILAR TO PREVIOUS DAYS) WHICH WILL HELP KEEP THE BEACHES IN THE
80S WITH THE FLOW OFF THE RELATIVELY COOLER SHELF WATERS.
A LIGHT GRADIENT IN PLACE WILL FAVOR DEVELOPMENT OF SEA-BREEZES FROM
BOTH COASTS...WITH AN EVENTUAL LATE DAY COLLISION OVER THE INTERIOR
ZONES. NUMERICAL GUIDANCE IS SHOWING THIS COLLISION TO BE HEALTHY
WITH A SWATH OF STRONG LOW LEVEL CONVERGENCE/FOCUS DOWN THE SPINE OF
THE PENINSULA AFTER 4PM THIS AFTERNOON. THE QUESTION IS WHETHER OR
NOT THIS COLLISION WILL BE STRONG ENOUGH FOR UPDRAFTS TO BREAK THE
LOWER LEVEL CAP AND THEN OVERCOME THE DRIER AIR ALOFT LONG ENOUGH TO
PRODUCE A FEW ISOLATED SHORT DURATION STORMS. THE DRY AIR ALOFT IS
CERTAINLY A MAJOR INHIBITING FACTOR AS THE COLUMN IS QUITE HOSTILE
TO DEEP CONVECTION ABOVE 10,000 FT. HOWEVER...SUCH A STRONG
COLLISION SHOULD BE ENOUGH TO PRODUCE SOMETHING...AND WILL KEEP A
20% CHANCE FOR AN ISOLATED STORMS WELL INLAND FROM THE I-75 CORRIDOR
DURING THE 4-9 PM EDT TIME FRAME. AS MENTIONED ABOVE...ANY ISOLATED
STORMS WILL BE SHORT-LIVED AS SIGNIFICANT ENTRAINMENT OF DRY AIR
INTO THE CONVECTIVE COLUMN SHORTENS THE LIFE CYCLE. AT THE SAME
TIME...ANY BRIEF STORMS THAT CAN BECOME ESTABLISHED WILL HAVE THE
POTENTIAL TO PRODUCE SOME GUSTY WINDS AS THEY COLLAPSE DUE TO THIS
EVAPORATIVE PROCESS.
ANY ISOLATED STORMS OVER THE INTERIOR WILL FADE QUICKLY AFTER
SUNSET...FOLLOWED BY A GENERALLY QUIET AND WARM OVERNIGHT PERIOD.
ONCE AGAIN WOULD EXPECT NORMALLY FOG PRONE AREAS TO EXPERIENCE A
PERIOD OF REDUCED VISIBILITIES AFTER MIDNIGHT.
&&
.MID TERM (SUNDAY-MONDAY)...
SCATTERED SHOWERS ALONG THE WEST COAST SEA BREEZE SUNDAY EVENING
WILL BE PUSHING WEST OFFSHORE OVER THE COASTAL WATERS UNDER EASTERLY
BOUNDARY LAYER FLOW AND WILL DISSIPATE BEFORE MIDNIGHT. S/W
DISTURBANCE OVER THE SOUTHEAST U.S. MAY DEVELOP AN MCS SUNDAY NIGHT
OVER SOUTHERN GEORGIA WHICH WOULD PUSH SOUTHEAST OVERNIGHT TOWARD
THE EXTREME NORTHERN NATURE COAST LATE...HOWEVER SHOWER AND
THUNDERSTORM ACTIVITY WILL LIKELY BE IN THE WEAKENING/DISSIPATING
STAGE AS IT APPROACHES LEVY COUNTY LATE SUNDAY NIGHT/EARLY MONDAY
MORNING. U/L RIDGE WILL BUILD OVER THE SOUTHEAST U.S. AND FLORIDA
MONDAY WITH A SURFACE RIDGE AXIS NORTH OF THE REGION WHICH WILL KEEP
WEST CENTRAL FLORIDA UNDER PREDOMINATELY EASTERLY BOUNDARY LAYER
FLOW. THIS WILL CONTINUE THE HEAT ACROSS THE AREA WITH AFTERNOON
TEMPERATURES IN THE LOWER TO MIDDLE 90S. ALTHOUGH DEEP LAYER
MOISTURE WILL BE LIMITED...BOUNDARY COLLISION OF EAST AND WEST COAST
SEA BREEZES DURING THE MID TO LATE AFTERNOON WILL GENERATE A SLIGHT
CHANCE OF AN AFTERNOON THUNDERSTORM. GIVEN RELATIVELY DRY AIR ALOFT
AND STRONG SURFACE HEATING CREATING RATHER STEEP LAPSE RATES WITH
GOOD POCKET OF COLD MID LEVEL AIR OVER THE REGION...ANY STORMS THAT
DO DEVELOP MAY BE STRONG TO SEVERE.
&&
.LONG TERM (TUESDAY-SATURDAY)...
HIGH AMPLITUDE PATTERN DEVELOPING ACROSS THE CONUS IN THE LONG RANGE
AS CUT-OFF LOW OVER THE SOUTHERN PLAINS WILL GRADUALLY FILL TUESDAY
THROUGH THURSDAY...WITH WEAK RIDGING AHEAD OF THIS SYSTEM REMAINING
OVER THE SOUTHEAST U.S. AND FLORIDA. DEEP LAYER MOISTURE WILL
INCREASE A BIT EACH DAY WITH AN INCREASING CHANCE OF AFTERNOON
THUNDERSTORMS ON WEDNESDAY. LEANING TOWARD ECMWF SOLUTION AS STRONG
U/L LOW IS EXPECTED TO DIG ALONG THE WEST COAST OF THE U.S. THURSDAY
NIGHT AND FRIDAY WHICH WILL PUMP UP THE RIDGE OVER THE CENTRAL
PLAINS...EXTENDING ACROSS THE SOUTHEAST U.S. AND FLORIDA. IN
CONTRAST...GFS EXTENDS AN EXTENSIVE L/W TROUGH FROM THE NORTHEAST
U.S. SOUTH ACROSS FLORIDA FOR THIS SAME TIMEFRAME. ECMWF IS WEAKER
WITH THIS TROUGH AND FURTHER EAST OVER THE WESTERN ATLANTIC. WITH
FORECAST RIDGE OVER THE AREA THE PREFERRED SOLUTION...EXPECT
TEMPERATURES TO RUN A FEW DEGREES ABOVE MOS GUIDANCE. EASTERLY
BOUNDARY LAYER FLOW IS EXPECTED TO PERSIST WITH A CHANCE OF
AFTERNOON THUNDERSTORMS ENHANCED BY THE COLLISION OF THE EAST/WEST
COAST SEA BREEZES MID TO LATE AFTERNOON THURSDAY THROUGH SATURDAY.
&&
.AVIATION...
PATCHY GROUND FOG IS BEGINNING TO DEVELOP ACROSS WEST-CENTRAL
FLORIDA. EXPECTING PERIODS OF MVFR CONDITIONS THROUGH SUNRISE...WITH
THE POTENTIAL FOR IFR/LIFR VIS AT THE MORE FOG PRONE TERMINALS SUCH
AS KPGD AND KLAL. ANY VIS RESTRICTIONS WILL QUICKLY LIFT WITH
SUNRISE THIS MORNING AND VFR CONDITIONS WILL THEN PREVAIL THROUGH
THE REMAINDER OF THE DAY/EVENING. JUST THE OUTSIDE CHANCE OF A BRIEF
SHOWER OR STORMS LATE IN THE DAY FOR KLAL...OTHERWISE DRY
CONDITIONS.
&&
.MARINE...
HIGH PRESSURE WILL REMAIN IN PLACE OVER THE EASTERN GULF OF MEXICO
THROUGH THE EARLY PORTION OF NEXT WEEK. WINDS AND SEAS WILL
GENERALLY BE ON THE LOW SIDE. SLIGHTLY STRONGER AND MORE GUSTY
CONDITIONS CAN BE EXPECTED NEAR THE COAST EACH AFTERNOON AS DAILY
SEA BREEZE CIRCULATIONS DEVELOP. BOATERS PLANNING ACTIVITIES NEAR
THE COAST LATER SUNDAY AFTERNOON AND EVENING SHOULD BE AWARE OF THE
POTENTIAL FOR RAPIDLY DEVELOPING THUNDERSTORMS THAT WILL TEND TO
MIGRATE OFFSHORE. SOME OF THESE STORMS ARE LIKELY TO BE ON THE+
STRONG SIDE.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL DOMINATE THE PATTERN OVER THE FLORIDA PENINSULA
THROUGH THE EARLY PORTION OF NEXT WEEK. RELATIVE HUMIDITY VALUES
WILL BRIEFLY APPROACH 35 PERCENT OVER THE INTERIOR THIS
AFTERNOON...HOWEVER WIDESPREAD RED FLAG CONDITIONS ARE NOT EXPECTED
AT THIS TIME. INCREASING LOW LEVEL MOISTURE AND SLIGHTLY COOLER
DAYTIME TEMPERATURES WILL PREVENT CRITICAL LEVELS OF RELATIVE
HUMIDITY FOR SUNDAY AND MONDAY. HOWEVER...WILL SEE BETTER CHANCES
FOR SCT LATE AFTERNOON AND EVENING STORMS BY THE SECOND HALF OF THE
WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 91 74 91 74 / 10 10 40 10
FMY 93 73 92 71 / 10 10 40 10
GIF 95 73 92 71 / 20 20 40 10
SRQ 87 74 90 73 / 10 10 30 20
BKV 94 68 93 69 / 10 10 40 10
SPG 90 76 89 76 / 10 10 30 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA
MID TERM/LONG TERM...OGLESBY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
346 AM EDT Sat May 24 2014
.Near Term [Through Today]...
IR satellite loops overnight, and upstream observations, indicate
that a layer of fairly dense cirrus is arriving in our forecast area
from the west. Forecast soundings and HRRR forecast cloud ceilings
suggest that this cirrus will persist for much of the day. Some
filtered sunshine is still expected at a minimum, so it should be
another very warm day. However, the added cloud cover will likely
make it a little cooler than yesterday. Our local hi-res (CAM) model
ensemble seemed to produce a reasonable maximum temperature forecast
based on the expected cloud cover, so we weighted expectations
toward that and made sure the forecast today was lower than observed
highs yesterday. Some recent 4km WRF runs - both from our office and
NCEP - have indicated a few showers and thunderstorms developing
along the sea breeze this afternoon, or in parts of southeast
Alabama where surface dewpoints will be a little higher. This is not
indicated by all WRFs, and global models remain dry. Given this, the
chance of rain today should not be too high, but we inserted a
mention of "isolated showers and thunderstorms" with a 10% PoP along
the Panhandle sea breeze and in southeast Alabama.
&&
.Short Term [Tonight Through Monday]...
Very interesting forecast will be coming up for the remainder of
the Memorial Day Weekend, as the current hot and dry pattern seemed
destined not to be able to last for much longer. If fact, the GFS
and ECMWF have come into fairly good agreement that the upper level
ridging which had been protecting our skies with fair and hot
weather, will gradually be sharpening up into a trof along the FL
east coast. This should give us a gradual increase in cloud cover
and rain chances on Sunday through Monday (especially across eastern
portions of the CWA) with high temps dropping back into the lower to
a few middle 90s. Additionally, with the steepening trof, still
adequate daytime heating, and fairly steep mid level lapse rates,
there appears to be some threat for a few strong to severe storms on
Sunday and Sunday night, again with the best chances and highest
PoPs furthest to the east. As of this package, did insert Isolated
Severe storms from 00 to 06 UTC Sunday night along the easternmost
corridor of the CWA, which also coincides with PoPs of 60 percent
(or the likely category). Further to the west, with Pops gradually
decreasing from 50 to 30 percent, still carried strong storm wording
with possible gusty winds.
.Long Term [Monday Night Through Friday]...
The GFS & ECMWF forecast a rather narrow, 500 mb long wave ridge
over the Southeast through Tuesday night, though the GFS ridge axis
is farther west than the ECMWF. Both models forecast a breakdown of
this ridge beginning Wednesday, though they continue to differ on
just how this occurs. Despite these differences, both solutions
bring a "backdoor" surface cold front into our forecast area later
in the workweek, with the GFS being faster and having the cold front
actually pass south of our region, while the ECMWF stalls the front
just to our north. The mean of these solutions has gradual ramp-up
in PoPs, from 20% or less through Wednesday, then 30-40% afterward.
The highest PoP will be during the afternoon & early evening hours,
when CAPE is highest. Temperatures will be near average, with highs
around 90 and lows in the 60s.
&&
.Aviation...
[Through 12Z Sunday] At ECP, TLH, and VLD, MVFR visibilities with
haze or light fog was reported around TAF issuance time. Therefore,
despite increasing cirrus cloud cover aloft some MVFR VIS in fog is
possible at those three terminals through around 12-13Z. At VLD,
some IFR VIS cannot be ruled out. Otherwise, VFR conditions are
expected with a high ceiling around 20-25kft.
&&
.Marine...
Generally light winds and low seas should prevail across the waters
during much if not all of the forecast period, with an onshore
component to the winds at most times.
&&
.Fire Weather...
Low-level moisture should continue to increase through the forecast
period, with RH staying above critical thresholds. Therefore, no red
flag conditions are expected.
&&
.Hydrology...
All of our rivers are remaining below flood stage, and should
continue a gradual decline. The one possible exception could be a
brief 0.50" to 0.75" that may fall along the Suwannee and
Withlacoochee River basins on Sunday through Monday, but even these
amounts would likely have little to no impact on area stages.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 94 66 92 67 91 / 10 10 30 40 30
Panama City 86 72 86 71 85 / 10 0 10 20 10
Dothan 91 68 94 69 92 / 10 10 20 30 30
Albany 92 68 91 69 92 / 10 10 40 40 40
Valdosta 96 67 93 67 91 / 10 10 50 60 40
Cross City 92 68 92 66 91 / 10 10 30 60 30
Apalachicola 90 71 88 70 86 / 10 0 10 20 10
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GOULD
LONG TERM...FOURNIER
AVIATION...LAMERS
MARINE...GOULD
FIRE WEATHER...LAMERS
HYDROLOGY...GOULD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
427 AM CDT Sat May 24 2014
...Updated long term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SAT MAY 24 2014
As the atmosphere destabilizes this afternoon the best instability
will be on the order of a couple of thousand J/kg located across
NW Kansas through central Kansas with less emphasis on the farther
western counties. Bulk shear values will be quite weak however. The
CAPE values will be owing largely to moisture as widespread low
level stratus will need to slowly erode this morning. With adequate
lift, a few rounds of shower and scattered thunderstorms will occur
again today as on Friday. The convective allowing models are not in
good agreement on the timing of convection as the 6Z runs are
indicating strongly forced convection between 00 and 06 UTC this
evening. The NAM solution expands what appeared to be the
aforementioned convection across the panhandles northward into
western Kansas later this morning associated with a isentropic lift
pattern. Initially we`ve maintained little if any POPS until around
18 z before ramping up chances through he afternoon and evening.
The current HRRR is not a tremendous help at this time as the
precipitation associated with the panhandles storm trends to
diminishing near Elkhart around 16 UTC. Beyond convective chances,
the highs will not be appreciably warmer than yesterday given the
expansive cloud cover. Another night of mild temperatures is
expected across central Kansas where temperature will not fall below
60 degrees, with stratus and potentially developing fog as
well.
.LONG TERM...(Sunday through Friday)
ISSUED AT 425 AM CDT SAT MAY 24 2014
The upper level low over the southwestern states today is progged by
the models to slowly move east into the Texas Panhandle by Memorial
Day. Weak disturbances rotating around this upper low will impact
the central High Plains through the weekend. Abundant low level
moisture will continue in place across the High Plains. This will
result in periods of scattered showers and thunderstorms through the
weekend, especially as the upper low and its associated colder air
aloft results in more destabilization. Hard to pin down the timing
on any specific disturbances but will at least show a diurnal trend
in precipitation chances.
Precipitation chances will continue off and on through Tuesday
before the upper low starts to move east out of the High Plains. By
midweek, an upper level ridge of high pressure will build into the
High Plains and push thunderstorm chances off to the south and east.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 218 AM CDT SAT MAY 24 2014
IFR ceilings will persist and potential for fog will need to be monitored
this morning as a light southeast surface flow persists with dew
point depressions of only a few degrees. Convective allowing models
and the NAM are not in good agreement on the timing for convective
initiation late in the day, however all terminals should be affected
by MVFR category TSRA/CBs late today or this evening.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 61 79 58 / 60 60 40 50
GCK 79 58 79 57 / 60 60 30 40
EHA 77 57 78 56 / 60 60 30 40
LBL 79 60 80 57 / 60 60 40 40
HYS 78 60 80 59 / 60 60 40 50
P28 80 63 78 62 / 60 60 40 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Gerard
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
409 AM CDT Sat May 24 2014
...updated short term...
.SYNOPSIS...
ISSUED AT 358 AM CDT SAT MAY 24 2014
Increasingly difluent flow aloft was developing across western
Kansas as the upper low had moved into Arizona. A broken line of
convection with widespread trailing stratiform was moving into the
panhandles region from New Mexico as of 3 am, just ahead of the 850
mb jet associated with the closed low. Farther east, scattered
showers had expanded east into eastern Kansas and ended completed
across central Kansas locations from Hays to Medicine Lodge.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SAT MAY 24 2014
As the atmosphere destabilizes this afternoon the best instability
will be on the order of a couple of thousand J/kg located across
NW Kansas through central Kansas with less emphasis on the farther
western counties. Bulk shear values will be quite weak however. The
CAPE values will be owing largely to moisture as widespread low
level stratus will need to slowly erode this morning. With adequate
lift, a few rounds of shower and scattered thunderstorms will occur
again today as on Friday. The convective allowing models are not in
good agreement on the timing of convection as the 6Z runs are
indicating strongly forced convection between 00 and 06 UTC this
evening. The NAM solution expands what appeared to be the
aforementioned convection across the panhandles northward into
western Kansas later this morning associated with a isentropic lift
pattern. Initially we`ve maintained little if any POPS until around
18 z before ramping up chances through he afternoon and evening.
The current HRRR is not a tremendous help at this time as the
precipitation associated with the panhandles storm trends to
diminishing near Elkhart around 16 UTC. Beyond convective chances,
the highs will not be appreciably warmer than yesterday given the
expansive cloud cover. Another night of mild temperatures is
expected across central Kansas where temperature will not fall below
60 degrees, with stratus and potentially developing fog as
well.
.LONG TERM...(Saturday night through Friday)
ISSUED AT 334 PM CDT FRI MAY 23 2014
Unsettled conditions will persist into the middle part of next
week as the very slow moving upper low over the southwest part of
the U.S. migrates into the plains. With time models have been moving
the low level forcing farther south and taking the threat of
heavier rains into OK and TX. It would appear that with a
relatively cold core there should still be convection across most
of my forecast area through at least Tuesday and perhaps into
Wednesday. Trying to pinpoint location and times of the
precipitation during that period is futile so will for the most
part broad brush pops. Temperatures will be moderated by pcpn and
cloud cover.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 218 AM CDT SAT MAY 24 2014
IFR ceilings will persist and potential for fog will need to be monitored
this morning as a light southeast surface flow persists with dew
point depressions of only a few degrees. Convective allowing models
and the NAM are not in good agreement on the timing for convective
initiation late in the day, however all terminals should be affected
by MVFR category TSRA/CBs late today or this evening.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 61 79 58 / 60 60 40 50
GCK 79 58 79 57 / 60 60 30 40
EHA 77 57 78 56 / 60 60 30 40
LBL 79 60 80 57 / 60 60 40 40
HYS 78 60 80 59 / 60 60 40 50
P28 80 63 78 62 / 60 60 40 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Russell
SHORT TERM...Russell
LONG TERM...Hutton
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS TOPEKA KS
327 AM CDT Sat May 24 2014
.SHORT TERM...(Today and Tonight)
Issued at 327 AM CDT SAT MAY 24 2014
Forecast for the next 24 hours remains mostly unchanged with a similar
environment seen for the past few days. Morning analysis shows the
upper trough responsible for this unsettled pattern rotating over
northern AZ with a broad upper ridge over the northern plains. A
series of embedded weak troughs were noted over the central plains.
One in particular across northern OK into southeast KS continues to
impact our CWA through the morning hours. A warm moist plume was
spreading northeast into southern and eastern Kansas as dewpoints
increase into the lower and middle 60s through the afternoon.
The increasing LLJ with the additional lift from the upper wave and
saturated atmospheric profile across northeast Kansas support the
current convection across southern portions of the area to continue,
if not increase in coverage through the morning and afternoon.
Activity is not expected to be severe through the day due to CAPE
values staying low near 1000 J/KG. Shear values, especially
directionally, increase a bit higher than yesterday in the 20 to 25
kt range with perhaps the stronger updrafts producing small hail and
gusty winds near 40 mph. The more pressing concern with convection
today will be the heavy rain. PWAT values increase to 1.6 inches
with mean h5 flow very weak suggesting slow-moving convection
generating outflow that triggers additional convection. The latest
NAM, GFS, ECMWF, and HRRR are similar in developing a heavier band
of rain impacting much of the area from now through at least 1 PM.
Areas near and south of Interstate 70 corridor stand the better
chances for flash flooding. A generous rainfall amount from 0.20 to
0.75 inches is likely with locally higher amounts from 1 to 2
inches with training convection. Likely precip chances decline to a
chance by this evening as guidance varies on if and where precip
redevelops from another weak upper wave.
Latest guidance was trending slightly cooler on temperatures today
due to extensive cloud cover and precip in the area. Lowered highs a
few degrees to the mid 70s but could still be too warm dependent on
precip coverage through the day. Lows this evening were unchanged in
the middle 60s.
.LONG TERM...(Sunday through Friday)
Issued at 327 AM CDT SAT MAY 24 2014
For Sunday through Tuesday, the forecast area is likely to remain
under the influence of the closed low to the west. Models are in
reasonably good agreement with the cut off low`s slow progression
east, and they maintain a conditionally unstable atmosphere with
decent moisture available and no real inhibition to convection.
With the occasional wave lifting out of the low providing some
forcing, scattered to numerous showers and thunderstorm should
develop. The forecast continues with POPs of 40 to 50 percent
during the daytime, mainly because there is no clear surface
feature to focus convection and pin point one location more likely
to receive precip over another. Deep layer sheer remains
unimpressive so organized severe weather looks unlikely. Really
with PWs near 1.5 inches, localized flash flooding remains the
main concern with the thunderstorm activity. Temps should not
change much from day to day since there is no real change in
airmass, so the temp forecast is generally a persistence forecast
of lows in the 60s and highs around 80.
By Wednesday, models are beginning to converge on an idea of the
closed upper low moving southeast gradually. Because of this the
forecast begins a trend down in POPs, but not completely doing
away with them. The GFS still suggests the atmosphere will be
conditionally unstable through the end of the week and that all is
needed might be some weak lift or weak forcing to generate precip.
Therefore some slight chances have been retained for Thursday and
Friday. Uncertainty is a bit higher for the end of the week since
the synoptic flow remains rather weak over the central plains.
This allows the GFS to bring a weak backdoor front into the area
while the ECMWF favors mid level ridging. Temps should see a
slight warming trend through the end of the work week due to
rising mid level heights and increases in insolation. However
strong warm air advection does not look to affect the area so
highs are forecast to warm into the mid 80s by Friday. Lows should
remain in the 60s.
&&
.AVIATION...(For the 06Z TAFs through 06Z Saturday Night)
Issued at 1149 PM CDT FRI MAY 23 2014
Initial concerns will be for BR near MHK, while TOP and FOE did
not receive nearly as much rain and may hold above 6SM for the
night. Next batch of showers and storms developing on the radar to
the south and have tried to time out with a tempo group for around
sunrise. Otherwise will be a day of periodic rain showers and will
hold as VCSH and need to adjust as waves approach and move
through.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...67
AREA FORECAST DISCUSSION
NWS JACKSON KY
138 AM EDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1032 PM EDT FRI MAY 23 2014
TEMPERATURES ALREADY DOWN INTO THE LOW TO MID 50S IN THE LAST HOUR
AND ON TRACK FOR MID 40S IN THE COLDEST VALLEYS. FORECAST IS ON TRACK
WITH TEMPERATURES...SO NO NEED FOR ANY UPDATES AT THIS TIME.
UPDATE ISSUED AT 704 PM EDT FRI MAY 23 2014
WITH DEWPOINTS MIXING INTO THE MID 40S THIS AFTERNOON..OPTED TO TAKE
LOWS IN THE COLDER VALLEYS DOWN A FEW DEGREES. OTHERWISE...FORECAST
IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 350 PM EDT FRI MAY 23 2014
18Z SFC ANALYSIS SHOWS CANADIAN HIGH PRESSURE DROPPING INTO THE OHIO
VALLEY TODAY BRINGING ITS DRIER AIR MASS AND COOLER TEMPS. THIS HAS
MADE FOR A PLEASANT AND COMFORTABLE DAY FOR MUCH OF EAST KENTUCKY
UNDER PARTLY TO MOSTLY SUNNY SKIES. JUST ALONG THE BORDER WITH
TENNESSEE A FEW SPRINKLES MAY OCCUR AND CONDITIONS WILL BE MORE
HUMID...AS A COLD FRONT SETTLES INTO THE SOUTH PARTS OF THE STATE.
DIFFERENCES BROUGHT BY THIS FRONT TO EAST KENTUCKY INCLUDE TEMPS
ONLY IN THE LOWER 70S ACROSS THE NORTH ALONG WITH DEWPOINTS IN THE
40S WHILE TO THE FAR SOUTH READINGS ARE IN THE MID AND UPPER 70S AND
DEWPOINTS CLOSER TO 60. NORTH TO NORTHWEST WINDS GENERALLY AT 5 TO 10
MPH...WITH SOME GUSTS TO 15 MPH...ARE FOUND THROUGH THE AREA AT THIS
TIME.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT AS THEY ALL DEPICT THE SLOW
EVOLUTION OF THE RIDGE AND TROUGH STRUCTURE THROUGH THE AREA. A
RELATIVELY SHARP TROUGH WILL SWEEP BY WELL TO THE NORTHEAST TONIGHT
ALLOWING HEIGHTS TO REBOUND INTO SATURDAY AS RIDGING EASES INTO THE
STATE FROM THE SOUTHWEST. THIS WILL ALSO PUSH THE TRACK OF ANY MINOR
MID LEVEL WAVES TO THE EAST OF THE AREA KEEPING THE FLOW PATTERN
RATHER SMOOTH OVER EAST KENTUCKY INTO SUNDAY MORNING. ON ACCOUNT OF
THE SIMILARITIES IN THE MODELS HAVE LEANED TOWARD THE LATEST RUNS OF
THE HRRR AND NAM12 FOR WEATHER SPECIFICS.
SENSIBLE WEATHER WILL FEATURE A COOLER NIGHT UNDER MOSTLY CLEAR
SKIES WITH THE FRONT OFF TO THE SOUTHWEST. A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT IS EXPECTED TO OPEN UP DURING THE EVENING AND
CONTINUE THROUGH THE NIGHT. PATCHY FOG WILL BE POSSIBLE IN THE
VALLEYS LATER TONIGHT AND INTO THE FIRST PART OF SATURDAY MORNING.
VERY PLEASANT WEATHER CAN BE EXPECTED ON SATURDAY AS COMFORTABLE
HUMIDITY LEVELS WILL CONTINUE ALONG WITH PLENTY OF SUNSHINE AND
TEMPERATURES TOPPING OUT IN THE MID TO UPPER 70S. SIMILAR CONDITIONS
TO TONIGHT/S WILL BE HAD SATURDAY NIGHT...THOUGH SFC HIGH PRESSURE
MOVING BY TO THE NORTH SHOULD YIELD MORE OF A RIDGE TO VALLEY
TEMPERATURE SPLIT BY SUNDAY MORNING THAN WE ANTICIPATE FOR TONIGHT.
AFTER AN EXTRA DAY FOR THE BOUNDARY LAYER TO DRY OUT...THE PATCHY FOG
SHOULD BE CONFINED TO MAINLY THE DEEPEST VALLEYS JUST AROUND DAWN
SUNDAY MORNING.
AGAIN USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPS...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
FILLING THE GAP TO THE END OF THE SHORT TERM. MOST OF THE ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES IN THE LOWS TONIGHT AND
A BIT MORE EXTENSIVELY ON SATURDAY NIGHT. AS FOR POPS...ENDED UP IN
LINE WITH THE MOS NUMBERS THROUGH SUNDAY MORNING HOLDING IN THE LOW
SINGLE DIGITS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 400 PM EDT FRI MAY 23 2014
FORECAST STILL SEEMS TO BE IN GOOD AGREEMENT FROM YESTERDAY TO
TODAY. AT 12Z SUNDAY...STRONG UPPER LEVEL RIDGING WILL BE MOVING
INTO THE OHIO VALLEY REGION...WITH A CLOSED LOW REMAINING STEADY
OVER THE SOUTHERN PLAINS DURING MUCH OF THE MID TERM. ANOTHER TROUGH
WILL FORM OVER THE NORTHEAST CONUS...WITH SEVERAL CLOSED WAVES
MOVING THROUGH OVER THE COURSE OF THE EXTENDED PERIOD. WITH THESE
TWO TROUGHS IN PLACE...EXPECT THE UPPER LEVEL RIDGE TO REMAIN THE
DRIVING FORCE THROUGH MUCH OF THE EXTENDED.
THE 300MB JET STREAM WILL REMAIN WELL TO OUR NORTH...PLAYING INTO
THE NEW ENGLAND TROUGHING DURING THE EXTENDED. MEANWHILE...WEAK FLOW
ACROSS THE OHIO VALLEY...AND SOUTHERN RIDGING...WILL MEAN WELL ABOVE
NORMAL TEMPS FOR KY INTO THE FIRST HALF OF THE WEEK. FOR MONDAY AND
TUESDAY...THERE WILL BE ENOUGH MOISTURE FLOW AND AFTERNOON
INSTABILITY THAT SOME DIURNAL ISOLATED /MONDAY/ TO LOW END SCATTERED
/TUESDAY/ SHOWER AND THUNDERSTORMS WILL BE POSSIBLE. THE GFS IS THE
MOST AGGRESSIVE WITH BRINGING MOISTURE INTO THE AREA DURING THIS
TIME...WHILE THE GEM AND ECMWF SHOW THE MAIN THREAT FOR PRECIP ON
TUESDAY AND NOT MONDAY. BASED ON THE UNCERTAINTY...AND SCATTERED
NATURE OF THIS SET UP...DECIDED TO STICK CLOSE TO THE ALLBLEND FOR
POPS DURING THIS TIME PERIOD.
BY TUESDAY EVENING...A SURFACE LOW WILL MAKES ITS WAY SE ACROSS THE
NEW ENGLAND STATES. IN DOING SO...IT WILL PUSH A SURFACE COLD FRONT
SOUTHWARD...MAKING IT INTO EASTERN KY IN THE FORM OF A BACK DOOR
FRONT TUESDAY NIGHT AND WEDNESDAY. THE GFS SEEMS TO BRING THE FRONT
THROUGH ABOUT 6 HOURS FASTER THAN THE ECMWF...WITH A BAND OF SHOWERS
AND THUNDERSTORMS PUSHING FROM NE TO SE TUESDAY EVENING THROUGH
WEDNESDAY EVENING. BEHIND THIS FRONT...SOMEWHAT DRIER AIR WILL
FILTER IN...ALONG WITH A SLIGHT COOL DOWN IN TEMPERATURES FOR
WEDNESDAY. NEITHER ONE WILL BE SIGNIFICANT. ONCE AGAIN...GIVEN THE
UNCERTAINTY BETWEEN THE TWO MODELS THIS FAR OUT...STUCK FAIRLY CLOSE
TO THE ALLBLEND SOLUTION FOR POPS.
ONCE THE FRONT MOVES THROUGH...THE SURFACE LOW WILL THEN SHIFT BACK
NORTHWARD. THIS COULD ALLOW THE OPPORTUNITY FOR THE FRONT...THOUGH
WEEK...TO PUSH BACK NORTHWARD INTO KY AS WELL LATE IN THE WEEK. THIS
COULD POSSIBLY PUSH MOISTURE BACK INTO THE CWA FOR
THURSDAY...FRIDAY...AND POINTS AFTER. UNCERTAINTY THIS FAR OUT DOES
NOT WARRANT ANY MORE THAN CHANCE POPS. DAYTIME HEATING WILL HELP TO
INITIATE ANY SHOWERS/TSTMS...SO EXPECT BEST CHANCE POPS DURING THE
AFTERNOON/EVENING HOURS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 138 AM EDT SAT MAY 24 2014
MAINLY VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 TO 36 HOURS. SOME
PATCHY MVFR FOG COULD DEVELOP LATE TONIGHT NEAR THE RIVER BEDS...BUT
SHOULD NOT IMPACT AIRPORTS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1234 AM CDT SAT MAY 24 2014
.AVIATION...
VFR FLIGHT CATEGORIES IN PLACE WITH SCATTERED TO BROKEN CLOUDS
AROUND 5-6 KFT WITH HIGHER CEILINGS ABOVE 15 KFT TO AROUND 30 KFT.
WITH A DEPARTING UPPER DISTURBANCE MOVING OUT OF THE AREA
MAY PRODUCE ISOLATED SHOWERS...BUT CHANCE TO SMALL TO INCLUDE
MENTION IN THE 24/06Z TERMINALS. LATER IN THE EARLY MORNING
PARTS OF DEEP E TX AND LOWER NW LA WILL SEE A MIX OF MVFR/IFR
CEILINGS AND VISIBILITIES...WHILE MOST OTHER LOCATIONS WILL SEE
BRIEF MVFR CEILINGS AND VISIBILITY RESTRICTIONS OF 3-5 STATUTE
MILES. THE MVFR/IFR CATEGORIES WILL QUICKLY RETURN TO VFR
CONDITIONS BETWEEN 24/13Z-24/15Z...WITH MORE MIDDLE CLOUDS LOWERING.
LIGHT AND VARIABLE WINDS TO LIGHT S-SW WINDS OF LESS THAN 7 KNOTS
EXPECTED THROUGH 24/15Z WHEN WINDS WILL BE MORE S FROM 4-8 KNOTS.
/06/
&&
.PREV DISCUSSION... /ISSUED 932 PM CDT FRI MAY 23 2014/
DISCUSSION...
SATELLITE IMAGERY THIS EVENING REVEALS EXTENSIVE AREAS OF ELEVATED
CLOUD COVER WHICH HAS RAPIDLY SPREAD E ACROSS THE REGION LATE THIS
AFTERNOON/EARLY EVENING...FROM CONVECTION OVER WCNTRL TX/SRN
OK...WITH ADDITIONAL PACIFIC MOISTURE STREAMING NE BENEATH THE AZ
CLOSED LOW...ORIGINATING FROM TS AMANDA OVER THE ERN PACIFIC. THE
00Z KSHV RAOB STILL REMAINS STRONGLY CAPPED AND QUITE DRY BENEATH
THE CLOUD COVER THIS EVENING...WITH UPPER RIDGING STILL PERSISTENT
ACROSS THE NATION/S MIDSECTION S TO THE GULF COAST. THE CONVECTION
TO OUR W HAS GRADUALLY SHOWN A VERY SLOW WEAKENING TREND OVER THE
LAST COUPLE OF HOURS...WITH THE SHORT TERM PROGS CONTINUING THIS
TREND OVERNIGHT EVEN AS A SHORTWAVE DRIFTS E INTO SW AR/NE TX
LATE. THE EARLIER PROGS WERE IN GOOD AGREEMENT WITH LITTLE IF ANY
QPF DEVELOPING LATE OVER THESE AREAS...WITH THE LATEST HRRR AND
NAM RUNS CONSISTENT WITH EARLIER RUNS WITH A MOSTLY DRY FORECAST.
THUS...HAVE TONED DOWN POPS TO SLIGHT CHANCE AFTER 06Z FOR THE
EXTREME NW ZONES...DROPPING POPS FARTHER SE...AS LIMITED MOISTURE
FARTHER S AND SUBSIDENCE BENEATH THE UPPER RIDGING IN PLACE SHOULD
PRECLUDE DEVELOPMENT ELSEWHERE OVERNIGHT. HAVE ALSO INCREASED
GRIDDED CLOUD COVER CONSIDERABLY THIS EVENING/OVERNIGHT...AS WELL
AS SATURDAY MORNING...BEFORE GRADUALLY DIMINISHING FROM W TO E BY
AFTERNOON.
EVEN WITH THE EXTENSIVE CLOUD COVER IN PLACE...02Z TEMPS ARE NEAR
THE OBSERVED READINGS 24 HOURS AGO...THUS MIN TEMPS SATURDAY
MORNING SHOULD BE COMPARABLE TO WHAT WAS OBSERVED THIS
MORNING...EXCEPT ACROSS THE ERN ZONES...WHERE SLIGHTLY WARMER
TEMPS ARE EXPECTED. HAVE ADJUSTED TEMPS AS SUCH...AS THEY RANGE
GENERALLY FROM THE MID TO UPPER 60S.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 66 87 66 87 67 / 0 10 10 10 10
MLU 65 88 64 88 65 / 0 10 10 10 10
DEQ 64 86 62 87 64 / 20 30 20 10 10
TXK 66 86 65 86 65 / 10 10 10 10 10
ELD 63 87 62 88 63 / 0 10 10 10 10
TYR 67 86 66 85 68 / 10 10 10 10 10
GGG 66 86 65 85 67 / 10 10 10 10 10
LFK 68 88 67 86 67 / 0 10 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
06
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
348 AM EDT SAT MAY 24 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE MID-ATLANTIC THIS WEEKEND
BEFORE SHIFTING OFFSHORE EARLY NEXT WEEK. A COLD FRONT WILL CROSS
THE REGION FROM THE NORTH TUESDAY NIGHT INTO WEDNESDAY WITH
HIGH PRESSURE AT THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
PRESSURE RISES WILL CONTINUE TODAY AS HIGH PRESSURE OVER LAKE
MICHIGAN APPROACHES THE MID ATLANTIC. A SHORTWAVE TROUGH WITH A CUT
OFF LOW IS OFF THE NJ COAST AND SUBSIDENCE BEHIND IT HAS LED TO
CLEAR SKIES ACROSS THE MID ATLANTIC. A PRESSURE SURGE WILL CONTINUE
THIS MORNING AND NW WINDS 5-10MPH WITH GUSTS AROUND 15 KTS WILL BE
POSSIBLE THIS MORNING.
NW FLOW ALOFT WILL CONTINUE ACROSS THE REGION TODAY WHILE HIGH
PRESSURE MOVES TOWARD THE MID ATLANTIC. SHORTWAVE ENERGY WILL WRAP
AROUND THE UPPER TROUGH AND COLD AIR ALOFT WILL LEAD TO CU
DEVELOPMENT ESPECIALLY NORTH AND EAST OF THE POTOMAC RIVER. A FEW
100 J/KG OF CAPE IS POSSIBLE AND FCST SOUNDINGS DO NOT SHOW ANY CAP
TODAY LIKE FRIDAY AFTERNOON. DEWPT DISCREPANCIES EXIST IN SOME OF
THE HI RES MODELS AND MOS THIS MORNING. WENT WITH RUC AND LAMP TODAY
AS THEY HAVE A GOOD REPRESENTATION OF LOWER DEWPTS BEING ADVECTED
FROM PA/OH THIS AFTERNOON. DOWNSLOPING FLOW WILL ALSO MIX DOWN LOWER
DEWPTS LESSENING THE CHANCE OF THUNDER AND THEREFORE KEPT A CHANCE
OF SHOWERS ACROSS NE MD THIS AFTERNOON.
THE PRESSURE GRADIENT BTW THE APPROACHING HIGH WILL STILL EXIST
TONIGHT AND NW WINDS AROUND 5 MPH ARE EXPECTED. TEMPS ARE EXPECTED
TO REACH THE LOW TO MID 50S AND NEAR 60 IN THE METROS AS WINDS WILL
LIMIT DECOUPLING. HIGH PRESSURE MOVES OVERHEAD SUNDAY AND TEMPS WILL
REACH THE UPPER 70S IN THE HIGHLANDS AND NEAR 80 ELSEWHERE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE OVER THE MID-ATLANTIC SUNDAY NIGHT MOVES OFF THE COAST
AND SETS UP OVER THE WESTERN ATLANTIC/SOUTHEAST STATES ON MONDAY.
MOISTURE STARTS TO INCREASE BY MONDAY...BUT LACK OF GOOD
FORCING/CONVERGENCE SHOULD PRECLUDE THUNDERSTORM DEVELOPMENT. HIGHER
THICKNESSES/850MB TEMPERATURES ALONG WITH SOUTHWEST WINDS WILL BRING
WARMER TEMPERATURES ON MONDAY...POSSIBLY REACHING THE UPPER 80S IN
SOME AREAS EAST OF THE BLUE RIDGE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MOISTURE INCREASE CONTINUES INTO TUESDAY...AND BY THEN MODEL
SOUNDINGS SUGGEST MORE IN THE WAY OF INSTABILITY. AT THE SAME
TIME...A COLD WILL APPROACH FROM THE NORTHWEST. COMBINATION OF THESE
FACTORS WILL LEAD TO A CHANCE OF SHOWERS AND THUNDERSTORMS
PARTICULARLY IN THE AFTERNOON WHEN MAXIMA IN THE MID TO UPPER 80S
ARE LIKELY.
CONVECTION COULD LINGER WELL INTO TUESDAY EVENING OR TUESDAY NIGHT
WITH A FRONTAL BOUNDARY DRAPED ACROSS THE CWA. THIS BOUNDARY SINKS
TO THE SOUTH DURING THE DAYTIME WEDNESDAY. THERE ARE STILL TIMING
UNCERTAINTIES WITH THE SOUTHWARD PROGRESS OF THE FRONT. WILL
CONTINUE WITH CHANCE POPS ON WEDNESDAY...BUT ITS POSSIBLE THAT THESE
MAY WIND UP BEING FOCUSED ACROSS THE SOUTH/SOUTHWEST PORTION OF THE
CWA BY AFTERNOON IF THIS IS WHERE THE FRONT IS LOCATED AT THAT TIME.
FRONTAL BOUNDARY ACROSS SOUTHERN VIRGINIA MAY SNAKE ITS WAY BACK
TOWARD THE HIGHLANDS FOR THURSDAY...SO WHILE EXPECT DRYING ACROSS
MUCH OF THE CWA THROUGH THE END OF THE WEEK WILL CONTINUE LOW POPS
IN THIS AREA.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED TODAY AND TONIGHT. NW WINDS AROUND 10 KTS
WILL CONTINUE THROUGH THE DAY WITH FREQUENT GUSTS AROUND 20KTS. HIGH
PRESSURE MOVES OVER THE REGION SUNDAY.
MONDAY...HIGH PRESSURE RESIDES OVER THE AREA FOR NO SIGNIFICANT
WEATHER. CHANCE OF THUNDERSTORMS RETURNS TUESDAY AND CONTINUES INTO
WEDNESDAY IN ASSOCIATION WITH A COLD FRONT.
&&
.MARINE...
HIGH PRESSURE WILL APPROACH THE WATERS TODAY AND NW WINDS WILL
CONTINUE TO GUST AROUND 20 KTS THROUGH THE MORNING. A SCA IS IN
EFFECT FOR THE LOWER TIDAL POTOMAC AND MD CHESAPEAKE BAY THROUGH 2PM
TODAY. THE PRESSURE GRADIENT WILL RELAX THIS AFTERNOON AND TONIGHT
AND NW WINDS 5-10 KTS ARE EXPECTED DURING THIS TIME.
HIGH PRESSURE MOVES OFF THE COAST BY MONDAY. GRADIENT IS FORECAST TO
BE FAIRLY WEAK SO NO SCA EXPECTED ATTM. COLD FRONT APPROACHES DURING
THE MIDDLE OF THE WEEK WITH A CHANCE OF THUNDERSTORMS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
ANZ530>534-537-539>541-543.
&&
$$
SYNOPSIS...BPP/HAS
NEAR TERM...HAS
SHORT TERM...BPP
LONG TERM...BPP
AVIATION...BPP/HAS
MARINE...BPP/HAS
AREA FORECAST DISCUSSION
NWS DULUTH MN
1136 PM CDT FRI MAY 23 2014
.UPDATE...
ISSUED AT 806 PM CDT FRI MAY 23 2014
SLOWED THE TIMING OF THE POPS INTO THE NW QUAD OF THE FA TO AFTER
06Z. STORMS THAT HAVE BEEN PERCOLATING THROUGH NW MN ARE
DIMINISHING AS THEY MOVE E INTO THE DRIER AIR. SFC RIDGE AXIS IS
OVER THE EASTERN EDGE OF THE FA AT 01Z WHICH IS ALLOWING FOR A SLY
WIND TO USHER IN WARM/MOIST AIR. MADE SOME MINOR ADJUSTMENTS TO
ACCOUNT FOR THIS TREND.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
AN UPPER LEVEL RIDGE AND SURFACE HIGH HAS KEPT THE NORTHLAND UNDER
MOSTLY SUNNY SKIES WITH WARM TEMPERATURES TODAY.
WAA TONIGHT...ALONG WITH INCREASING INSTABILITY AND STEEPER LAPSE
RATES MAY LEAD TO SOME SHOWERS OVER PORTIONS OF OUR
WESTERN/NORTHERN CWA. SHOWERS AND THUNDERSTORMS HAVE FIRED OVER
FAR WESTERN MINNESOTA THIS AFTERNOON...AND THE LATEST HRRR DEPICTS
THIS AND HAS IT DIMINISHING WITH LOSS OF HEATING AND AS IT MOVE
AWAY FROM THE BETTER INSTABILITY. THE LATEST WRF-NMM ALSO DEPICTS THIS
ACTIVITY AND HAS IT DISSIPATING BEFORE IT REACHES OUR CWA. WE WILL
LEAVE IT OUT EARLY THIS EVENING...THEN KEEP SOME SMALL POPS LATER
TONIGHT.
LOWER STABILITY WILL RESIDE OVER FAR NORTHERN MINNESOTA
SATURDAY...AND WE KEPT A MENTION OF SOME SHOWERS OR THUNDERSTORM
THERE. MOST AREAS WILL SEE PARTLY TO MOSTLY SUNNY SKIES THOUGH AND
TEMPERATURES A BIT WARMER THAN TODAY. WE THINK THE SOUTHWEST FLOW
WILL BE STRONG ENOUGH TO KEEP A LAKE BREEZE FROM FORMING AT THE
HEAD OF THE LAKE AND ALONG THE SOUTH SHORE FOR MUCH OF THE DAY.
HOWEVER...ONE MAY BE ABLE TO DEVELOP LATE IN THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 23 2014
GOOD CONTINUITY FROM PREVIOUS FCST WITH A SOMEWHAT SPLIT FLOW IN THE
MID LVLS THIS PERIOD. THERE ARE TWO KEY FEATURES OF NOTE IN THE NEXT
5 TO 7 DAYS. FIRST...A SLOW MOVING CLOSED LOW OVER THE SRN ROCKIES
WILL TRACK INTO THE SRN PLAINS BY MIDWEEK. SECOND...A WEAK FRONTAL
BDRY ACCOMPANIED BY A SHORTWAVE TROF WILL SLIDE OVER THE CWA AMIDST
A DEVELOPING RIDGE. THIS SECOND FEATURE WILL BRING A PERIOD OF
SHOWERS/STORMS TO THE NORTHLAND MAINLY SUNDAY AND SUNDAY NIGHT.
THERE ARE DIFFERENCES IN HOW FAST INITIAL PRECIP MOVES INTO THE AREA
HOWEVER GOOD AGREEMENT EXISTS IN THE MASS FIELDS TO HAVE MODERATE
CONFIDENCE IN THE FCST. GEM REMAINS AN OUTLIER SIMILAR TO YESTERDAY
SO ITS OUTPUT WAS GIVEN LOWER CONSIDERATION. MAIN CHANGE TO
YESTERDAYS FCST WAS TO PUSH PRECIP OUT OF THE REGION MORE QUICKLY
MONDAY AS FRONTAL BDRY HEADS SOUTH AND SFC HIGH BUILDS INTO THE
AREA. BUILDING MID LVL RIDGE TUESDAY SHOULD ASSIST WITH STRENGTHENING
OF SFC HIGH AND WEDGE OF COOL DRY AIR ADVECTING DOWN LAKE INTO TWIN
PORTS. LATER FCSTS MAY NEED TO LOWER TEMPS/DEWPOINTS DURING THIS
TIME. WILL KEEP MON NIGHT THROUGH WED NIGHT DRY UNTIL NEXT POTENTIAL
FOR PRECIP ARRIVES LATE WEEK. TEMPS REMAIN ABOVE CLIMO EXCEPT NEAR
IMMEDIATE LAKEFRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1136 PM CDT FRI MAY 23 2014
VFR THROUGH THE FORECAST. HAVE REMOVED THE VCSH MENTION FROM
PREVIOUS FORECAST EXCEPT AT INL WHERE HAVE A VCSH MENTION
BEGINNING AT 09Z. CARRY THIS THROUGH 16Z PER LATEST NAM12 AND
HRRR/RAP. GUSTY SFC WINDS EXPECTED AT INL/HIB/BRD AROUND
16Z...DIMINISHING NEAR 00Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 50 76 56 78 / 0 10 10 20
INL 55 80 58 74 / 20 20 30 60
BRD 55 81 59 81 / 0 10 20 40
HYR 49 79 54 81 / 0 0 0 10
ASX 46 78 53 80 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...MELDE
LONG TERM...CANNON
AVIATION...GSF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
338 AM CDT SAT MAY 24 2014
.SYNOPSIS...
ISSUED AT 337 AM CDT SAT MAY 24 2014
A STATIONARY FRONT CURRENTLY EXTENDS ACROSS NORTHERN OKLAHOMA AS A
CLOSED UPPER LOW EXISTS OVER ARIZONA. SCATTERED SHOWERS ARE LIFTING
NORTH ACROSS THE WESTERN SANDHILLS WITH A FEW SHOWERS IN CENTRAL
NEBRASKA. DEWPOINTS ACROSS WESTERN NEBRASKA ARE IN THE UPPER 50S.
SOME PATCHY FOG HAS ALSO DEVELOPED IN SOME AREAS ALTHOUGH VISIBILITIES
ARE CURRENTLY NO LOWER THAN 5SM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CDT SAT MAY 24 2014
ONLY A SLIGHT CHANCE FOR SHOWERS THROUGH MID MORNING WITH VERY
LITTLE FORCING TO INITIATE DEVELOPMENT. EXPECT PATCHY FOG OVER MOST
OF WESTERN NEBRASKA THIS MORNING TO END BY 15Z. THE LATEST KLBF
SOUNDING INDICATED PWAT OF 1.23 INCHES WHICH IS 180 PERCENT OF
NORMAL. AS THE UPPER LOW CONTINUES ITS SLOW EASTWARD PROGRESSION
INTO WESTERN NEW MEXICO...THE SLOW MOVEMENT WILL RESULT IN A SIMILAR
ENVIRONMENT OVER THE HIGH PLAINS TODAY. HIGHS TODAY REMAIN VERY NEAR
PREVIOUS FORECAST OF NEAR 75 DEGREES. EXPECT A CHANCE FOR
SHOWERS AND EMBEDDED THUNDER LATE THIS MORNING THROUGH THE AFTERNOON
WITH LOCALLY HEAVY RAIN POSSIBLE. COVERAGE REMAINS UNCERTAIN AS
INDICATED BY MODEL DIFFERENCES. THE HRRR MODELS SEEMS THE MOST IN
LINE WITH EXPECTED DEVELOPMENT TIED WITH DIURNALLY DRIVEN
ENVIRONMENT. IN FACT AFTER 00Z...POPS LIMITED TO A SLIGHT CHANCE
OVERNIGHT. ALSO A REPEAT OF PATCHY FOG IS FAVORABLE ACROSS CENTRAL
AND SOUTHEAST AREAS AFTER 09Z.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 337 AM CDT SAT MAY 24 2014
SUNDAY AND BEYOND. THE MAIN FORECAST CHALLENGE IN THE EXTENDED
CONTINUES TO BE PRECIPITATION CHANCES IN ASSOCIATION WITH A
STUBBORN UPPER LEVEL LOW ATOP THE DESERT SOUTHWEST. ON
SUNDAY...THE UPPER LOW WILL HAVE PROGRESSED TO THE FOUR CORNERS
REGION...BUT WILL CONTINUE TO MEANDER IN THE VICINITY OF THE
SOUTHERN ROCKIES THROUGH AT LEAST MIDDAY ON MONDAY. ANOTHER ROUND
OF PRECIPITATION IS ANTICIPATED FOR SUNDAY. THE HIGHEST CHANCE OF
POPS ARE ASSOCIATED WITH A WEAK SURFACE TROUGH THAT IS BISECTING
NORTHWESTERN NEBRASKA AND ACROSS OUR EASTERN ZONES WHERE
INSTABILITY IS ANTICIPATED TO BE HIGHEST. IT APPEARS ONCE AGAIN
THAT CONVECTIVE INHIBITION WILL BE WEAK ACROSS THE ENTIRE FORECAST
AREA...MULTIPLE CLUSTERS OF STORMS ARE EXPECTED. GIVEN THAT
FORECAST PWATS THROUGH THE AFTERNOON HOURS ARE ANTICIPATED TO BE
GREATER THAN 125% OR MORE OF AVERAGE...AND WITH STORM MOTIONS OF
15 KTS OR SO...DECENT RAINFALL AMOUNTS ARE POSSIBLE ONCE AGAIN.
FOR EARLY NEXT WEEK...THE UPPER LOW WILL RELUCTANTLY EJECT ONTO
THE SOUTHERN PLAINS...BUT SUFFICIENT FORCING AND MOISTURE REMAIN
FOR ADDITIONAL PRECIPITATION CHANCES. THE PLACEMENT OF THE UPPER
LOW WOULD FAVOR SOUTHEASTERN PORTIONS OF THE FORECAST AREA DURING
THE AFTERNOON HOURS MONDAY WHEN THE CAPPING INVERSION IS WEAKEST.
WILL MAINTAIN 40 PERCENT MENTION...BUT LIMIT THE OTHER PERIODS AT
SLIGHT CHANCE OR LESS. THE UPPER LOW CONTINUES TO MEANDER AND
SLOWLY FILL ACROSS THE SOUTHERN PLAINS THROUGH MIDWEEK AS A RIDGE
OF HIGH PRESSURE BUILDS ACROSS ROCKIES/CENTRAL CONUS.
PRECIPITATION CHANCES COME TO AN END FOR MOST LOCATIONS ON TUESDAY
AS THE RIDGE SHOULD SUPPRESS VERTICAL LIFT. THE DRY FORECAST
CONTINUES TO AT LEAST THURSDAY WHEN A BROAD TROUGH OF LOW PRESSURE
DEEPENS ACROSS THE WESTERN CONUS...THIS FORCES THE RIDGE EAST AND
ALLOWS FOR A RETURN TO SOUTHWESTERLY FLOW ATOP THE CENTRAL HIGH
PLAINS. WITH THE BUILDING RIDGE...TEMPERATURES WILL WARM BACK INTO
THE 80S FOR MOST IF NOT ALL LOCATIONS ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA THROUGH AT LEAST MID WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 158 AM CDT SAT MAY 24 2014
MVFR CEILINGS ARE FORECAST TO FALL TO IFR AFTER 09Z AT KLBF WHILE
VFR CEILINGS FALL TO MVFR AFTER 09Z AT KVTN. THE CEILINGS ARE FORECAST
TO IMPROVE TO VFR BY 18Z FOR BOTH TAF SITES. VISIBILITES ARE
FORECAST TO FALL TO 3-5SM BETWEEN 09Z AND 14Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1247 AM CDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1230 AM CDT SAT MAY 24 2014
UPDATE MAINLY FOR POP/WEATHER TRENDS OVERNIGHT. THE 04Z RAP GUIDANCE
HAS LOCKED IN REASONABLY WELL ON THE CURRENT AREA OF CONVECTION
STRETCHING ALONG AND NORTH OF INTERSTATE 94. THIS MODEL GRADUALLY
DIMINISHES THE STORMS THROUGH THE EARLY MORNING HOURS AND
GENERATES SOME ADDITIONAL STORMS ACROSS THE NORTHWEST TOWARD
DAYBREAK. SLOW STORM MOVEMENT AND REPEAT STORMS HAVE LED TO SOME
HEAVY RAINFALL OVER PARTS OF NORTHERN BURLEIGH COUNTY AND KIDDER
COUNTY. THE FLASH FLOOD WARNING ISSUED EARLIER FOR EASTERN
STUTSMAN COUNTY HAS BEEN REPLACED BY AN AREAL FLOOD WARNING...AND
FORTUNATELY...ADDITIONAL HEAVY RAIN HAS NOT OCCURRED OVER THE SAME AREA.
WILL CONTINUE TO MONITOR THE HYDRO SITUATION OVERNIGHT. A FEW
STORMS HAVE PULSED UP BRIEFLY...PROMPTING ISSUANCE OF SPECIAL
WEATHER STATEMENTS...BUT STILL ANTICIPATING STORMS WILL STAY JUST
BELOW SEVERE LIMITS IN TERMS OF HAIL.
UPDATE ISSUED AT 1014 PM CDT FRI MAY 23 2014
MAIN UPDATE CONCERNS ARE CONVECTION TONIGHT. EARLIER CONVECTION
LOOKS TO HAVE LAID AN EAST TO WEST BOUNDARY ALONG INTERSTATE 94
WHICH CONTINUES TO LIFT SLOWLY NORTH. HAVE THUS KEPT AT LEAST A
SLIGHT CHANCE OF THUNDER ACROSS CENTRAL NORTH DAKOTA ALONG AND
NORTH OF THE I94 CORRIDOR.
UPDATE ISSUED AT 639 PM CDT FRI MAY 23 2014
MAIN ISSUE THIS EVENING WAS THUNDERSTORMS MAINLY ALONG AND SOUTH
OF INTERSTATE 94. MOST SIGNIFICANT IS IN THE JAMESTOWN AREA WHERE
A SEVERE THUNDERSTORM HAS BEGUN TO BACK BUILD INTO THE JAMESTOWN
AREA. ADDITIONAL CONVECTION TO THE SOUTHWEST OF JAMESTOWN MAY ALSO
MOVE INTO THIS AREA WHERE GENERALLY 1 TO 2 INCHES OF RAIN HAS
ALREADY FALLEN...WITH LOCALLY HIGHER AMOUNTS LIKELY. HAVE BUMPED
UP POPS SIGNIFICANTLY OVER SOUTHERN STUTSMAN COUNTY...THEN TAPERED
TO CHANCE POPS SOUTH SOUTHWEST OF HERE INTO SOUTHWEST NORTH
DAKOTA. OTHERWISE NO SIGNIFICANT CHANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 255 PM CDT FRI MAY 23 2014
MAIN FORECAST CONCERNS ARE CONVECTIVE POTENTIAL...TIMING AND
PLACEMENT. VIS IMAGERY CONTINUES TO SHOW CU FIELD DEVELOPING
ACROSS SOUTHEAST CWA IN AREA OF DEWPOINTS AROUND 60F. A FEW
LIGHTNING STRIKES TO OUR EAST IN FGF CWA. MODELS CONTINUE TO
INDICATE BEST POTENTIAL FOR THIS AFTERNOON AND EVENING ACROSS
JAMES VALLEY REGION. WILL CONTINUE TO COVER WITH LOW POPS DUE TO
ISOLATED/SCATTERED NATURE OF EXPECTED CONVECTION. PLENTIFUL
INSTABILITY IN PLACE WITH LATEST SPC MESO ANALYSIS SHOWING
1500-2500 J/KG SURFACE BASED INSTABILITY NUDGING INTO SOUTH
CENTRAL ND ALTHOUGH AS PREVIOUSLY MENTIONED SHEAR IS LIMITED WITH
BEST 0-6KM SHEAR VALUES OF 20-25KTS ACROSS SOUTHEAST. ANY
CONVECTION THAT DEVELOPS SHOULD DIMINISH BY MID EVENING.
INSTABILITY REMAINS IN PLACE ON SATURDAY WHILE SHORTWAVE IN
SOUTHWEST FLOW AND ASSOCIATED SURFACE FRONT APPROACH BY AFTERNOON.
DIFFICULT TO PIN DOWN EXACT PLACEMENT FOR STORMS ON SATURDAY SO
WILL CONTINUE TO CARRY CHANCE POPS MOST LOCATIONS. SPC HAS WESTERN
ND IN /SEE TEXT/ DISCUSSION FOR POSSIBILITY OF A COUPLE
STRONG/SEVERE STORMS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 255 PM CDT FRI MAY 23 2014
A MID LEVEL SHORTWAVE CIRCULATING AROUND THE CLOSED UPPER LOW IN THE
FOUR CORNERS WILL PEEL OFF AND GET ABSORBED IN THE NORTHERN STREAM
FLOW. THIS SHORTWAVE WILL CROSS INTO SOUTHWEST NORTH DAKOTA SATURDAY
NIGHT AS IT SLIDES OVER A LEE SIDE LOW IN EASTERN MONTANA. IN DOING
SO EXPECT THIS TO BECOME THE FOCUS FOR SHOWERS AND THUNDERSTORMS
SATURDAY NIGHT INTO SUNDAY AS THE LEE SIDE TROUGH BECOMES A COLD
FRONT AND MOVES EAST ACROSS WESTERN AND CENTRAL NORTH DAKOTA. ALONG
THE FRONT...THE STRONGEST 0-6KM SHEAR OF 30KT TO 35KT IS FORECAST TO
LINE UP WITH BULLS EYE OF THE MOST UNSTABLE CAPE. THE GFS IS
SLIGHTLY SLOWER WITH THE ADVANCING COLD FRONT SUNDAY...BEING WEST OF
BISMARCK AT 18Z...WHILE THE NAM AND ECMWF ALREADY HAVE THE FRONT
JUST EAST OF BISMARCK. DEPENDING ON WHERE THE FRONT ACTUALLY ENDS UP
WILL DETERMINE HOW FAR WEST THE LIKELY POPS AND POTENTIAL FOR SEVERE
THUNDERSTORMS WILL EXTEND. THERE ARE SOMEWHAT STRONGER SHEAR VALUES
BEHIND THE FRONT BUT INSTABILITY PARAMETERS ARE ALSO WEAKER. WILL
CONTINUE WITH THE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
ALONG AND AHEAD OF THE FRONT WITH SCATTERED SHOWERS BEHIND THE
FRONT. MODELS DEPICT A DRY AFTERNOON IN THE FAR WEST WHICH WILL
GRADUALLY PROPAGATE ACROSS CENTRAL NORTH DAKOTA SUNDAY EVENING/NIGHT
AS THE COLD FRONT AND SHORTWAVE SHIFT EAST SUNDAY EVENING.
ON MONDAY...THE GEM/ECMWF SHOW A FLATTER HEIGHT FIELD VERSUS THE GFS
WHICH HAS A MORE AMPLIFIED H7-H5 RIDGE IN PLACE KEEPING ANY THREAT
OF SHOWERS OR THUNDERSTORMS FROM ENTERING THE WEST UNTIL AFTER 00Z
TUESDAY. MEMORIAL DAY STILL LOOKS DRY THROUGH THE EARLY EVENING AND
WILL CONTINUE THIS TREND IN THE GRIDDED FORECAST AS THE PREVIOUS
FORECAST HAD.
MONDAY NIGHT INTO WEDNESDAY...A SOUTHWEST FLOW IS THE
DOMINANT UPPER AIR PATTERN ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WITH A SERIES OF SHORTWAVES RIDING THROUGH. DAILY AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS WILL BE SCATTERED ABOUT WESTERN
AND CENTRAL NORTH DAKOTA DURING THIS TIME.
BEYOND WEDNESDAY...THE LATEST GFS WANTS TO BUILD A HIGHLY AMPLIFIED
RIDGE INTO NORTH DAKOTA THURSDAY THROUGH SATURDAY. THE ECMWF BRIEFLY
SHOWS THIS FOR WEDNESDAY NIGHT INTO THURSDAY THEN SHIFTS IT EAST
WITH A RETURN TO AN UNSETTLED WEATHER BY THURSDAY. PLENTY OF
UNCERTAINTY AS TO WHETHER OR NOT A BRIEF BREAK IN THUNDERSTORM
CHANCES OCCURS OR WILL IT BE MORE OF AN EXTENDED BREAK. HIGH
TEMPERATURES WILL BE IN THE 70S THROUGH WEDNESDAY WITH POSSIBLE 80S
IF THE RIDGE TAKES SHAPE AND DOMINATES TOWARD THE END OF THE
EXTENDED. OVERNIGHT LOWS ARE FORECAST MAINLY IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1230 AM CDT SAT MAY 24 2014
CONVECTION REMAINS AROUND AND TO THE WEST. WILL KEEP A MENTION OF
THUNDER THROUGH AROUND 09Z. OTHERWISE...THUNDER ACROSS CENTRAL
NORTH DAKOTA HAS MOVED NORTH OF KDIK AND KBIS SO HAVE REMOVED VCTS
AT REMAINING TAF SITES TONIGHT. A SOUTHERLY FLOW WILL CONTINUE
THROUGH THE FORECAST PERIOD. BROUGHT VCTS ACROSS ALL AERODROMES
AGAIN SATURDAY AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RP KINNEY
SHORT TERM...JNS
LONG TERM...KS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
248 AM EDT SAT MAY 24 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH TODAY...TRIGGERING ANOTHER
ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN THE
AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD OVER
THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS LIKELY
TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
LOW LVL MOISTURE TRAPPED BENEATH SUBSIDENCE INVERSION IS
SUSTAINING STRATOCU DECK ACROSS MUCH OF CENTRAL PA EARLY THIS AM.
LOWERING INVERSION HGT SHOULD RESULT IN CLEARING SKIES LATER THIS
MORNING...BTWN 10Z-14Z BASED ON RAP SOUNDINGS AND LAMP GUIDANCE.
THE CLOUD COVER AND A NW BREEZE SHOULD KEEP TEMPS FROM FALLING
MUCH FROM 06Z READINGS...WITH MIN TEMPS LIKELY RANGING FROM THE
M40S OVR THE ALLEGHENIES...TO THE M50S OVR THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SUNDAY/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIAN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIGHEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERATURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
INVERSION LOWERING AS HIGH PRESSURE BUILDS INTO THE REGION
OVERNIGHT...BUT TRAPPED MOISTURE PRODUCING WIDESPREAD STRATOCU
DECK ACROSS THE WEST AND NORTH. MVFR CONDITIONS EXPECTED FROM
KAOO-KUNV-KIPT WITH IFR/LIFR DEVELOPING FROM KBFD-KJST. WINDS WILL
CONTINUE TO DECOUPLE AND RANGE BETWEEN 5-10 KTS AT THE SURFACE
THROUGH THE OVERNIGHT.
STRATOCU WILL MIX OUT BETWEEN 10-14Z AS WIDESPREAD VFR CONDITIONS
RETURN UNDER PARTLY TO MOSTLY SUNNY SKIES. COLDER AIR STILL IN
PLACE ALOFT ALONG WITH A SHORTWAVE SLIDING THROUGH AND INCREASING
LAPSE RATES FURTHER SHOULD PROVIDE ENOUGH INSTABILITY TO GENERATE
SCT SHOWERS AND ISOLATED THUNDERSTORMS MAINLY IN THE EAST DURING
THE AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
226 AM EDT SAT MAY 24 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE AND A SURFACE FRONTAL BOUNDARY WILL
MOVE SOUTH ACROSS THE COMMONWEALTH TODAY...TRIGGERING ANOTHER
ROUND OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN THE
AFTERNOON. HIGH PRESSURE OVER THE GREAT LAKES WILL THEN BUILD OVER
THE REGION DURING THE MEMORIAL DAY WEEKEND. A COLD FRONT IS LIKELY
TO CROSS THE STATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
LOW LVL MOISTURE TRAPPED BENEATH SUBSIDENCE INVERSION IS
SUSTAINING STRATOCU DECK ACROSS MUCH OF CENTRAL PA EARLY THIS AM.
LOWERING INVERSION HGT SHOULD RESULT IN CLEARING SKIES LATER THIS
MORNING...BTWN 10Z-14Z BASED ON RAP SOUNDINGS AND LAMP GUIDANCE.
THE CLOUD COVER AND A NW BREEZE SHOULD KEEP TEMPS FROM FALLING
MUCH FROM 06Z READINGS...WITH MIN TEMPS LIKELY RANGING FROM THE
M40S OVR THE ALLEGHENIES...TO THE M50S OVR THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SUNDAY/...
ANOTHER SHORTWAVE AND RATHER WELL DEFINED SFC TROUGH IS SLATED TO
DIVE SE ACROSS THE REGION ON SATURDAY. ALTHOUGH THIS FEATURE
APPEARS TO BE CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME
RESPECTS...MIXED LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED
J/KG HIGHER...WITH SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD
ACROSS A GREATER PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION.
HIGH TEMPS SATURDAY SHOULD BE ABOUT 5F DEG HIGHER THAN
FRIDAY ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND SUSQ VALLEY.
HOWEVER...THE NRN AND WESTERN MTNS COULD BE AS MUCH AS 8-10F
WARMER.
GRADUAL CLEARING SAT NIGHT AND LIGHT WIND LATE WILL ALLOW FOR
ANOTHER CHILLY NIGHT WITH MINS NEAR 40F ACROSS THE PERENNIAL COLD
SPOTS OF THE NORTH...AND MID 40S TO LOWER 50S HEADED SE TO THE
LOWER SUSQ VALLEY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
UPPER FLOW OVER THE NORTHEAST LOOKS TO REMAIN FAIRLY WESTERLY AS
THE REGION SITS BETWEEN UPPER LOW OVER THE CANADIAN MARITIME
PROVINCES AND AN UPPER RIDGE OVER THE SE STATES TRYING TO BUILD
NORTHWARD.
AT THE SFC HIGH PRESSURE IS EXPECTED TO DOMINATE WITH THE
CONFLUENT FLOW ALOFT. A SHORTWAVE IN THE NORTHERN STREAM WILL
BRING A COLD FRONT THROUGH THE AREA ON TUESDAY...STALLING OUT TO
THE SOUTH OF THE STATE ON WEDNESDAY. THIS REMAINS THE HIGHEST CHC
OF RAINFALL IN AN OTHERWISE DRY EXTENDED FCST. ABOVE NORMAL
TEMPERATURES EARLY IN THE PERIOD...MONDAY AND TUE...WILL BE
KNOCKED BACK TO NEAR NORMAL FOLLOWING THE MID WEEK FROPA FOR THRU
AND FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS CONTINUE TO FILL IN OVERNIGHT AS COLD AIR STREAMS OVER THE
NW MTNS AND THE LAURELS. MIXING CONTINUES THROUGH MOST OF CENTRAL
AND SOUTHWEST PA...THIS HAS ALLOWED FOR GUSTY WINDS TO CONTINUE
THROUGH THE FIRST HALF OF THE EVENING. EXPECT THAT THESE WINDS
SHOULD SUBSIDE AS THE REGION DECOUPLES BY 06Z. MVFR AND LOWER
CIGS HAVE OCCURRED AT JST...WITH LIFR CIGS AND VSBYS AT BFD. THSE
CONDITIONS AT BFD SHOULD CONTINUE OVERNIGHT UNTIL THEY BEGIN TO
LIFT AROUND 12Z...TO MVFR AND THEN TO VFR BY 15Z. JST SHOULD LOWER
OVERNIGHT TO IFR BEFORE LIFTING BY 12Z.
SATURDAY WILL AGAIN FEATURE SOME PATCHY LOW CLOUDS AND FOG EARLY
FOLLOWED BY PARTLY TO MOSTLY SUNNY SKIES DURING THE MID TO LATE
MORNING...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING IN THE
AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.SUN...AM FOG POSSIBLE...OTHERWISE VFR.
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
141 AM EDT SAT MAY 24 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL OUT OVER GEORGIA TONIGHT. SURFACE HIGH
PRESSURE WILL THEN DRIFT EASTWARD FROM THE OHIO VALLEY TO THE
OFFSHORE ATLANTIC WATERS OVER THE WEEKEND. THE REGION IS EXPECTED TO
BE BACK UNDER THE INFLUENCE OF THE BERMUDA HIGH BY EARLY NEXT WEEK
WITH DEWPOINTS AND TEMPERATURES WARMING.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 140 AM...FCST LOOKS ON TRACK WITH THIS UPDATE.
AS OF 1045 PM EDT FRIDAY...RATHER CALM EVENING IN STORE FOR THE
REGION AS COLD FRONT HAS PUSHED SOUTH INTO THE MIDLANDS LEAVING
BEHIND A DRIER AIRMASS. DEWPOINTS CONTINUE TO FALL INTO THE LOWER
60S TO MID 50S AT MOST LOCATIONS UNDER LIGHT TO MODERATE NORTHERLY
WINDS. PULLED ALL POPS FOR THE REMAINDER OF THE OVERNIGHT AND LEFT
THE REST OF THE FORECAST AS IS FOR THIS UPDATE.
PREVIOUS DISCUSSION...
AS OF 230 PM EDT...CONVECTION REMAINS LARGELY BENIGN ATTM WITH
MAINLY SCT CU OVER SOME OF THE MTNS AND WRN UPSTATE. UNDER STILL
BRISK MID-UPPER LEVEL NW FLOW...MTN WAVE CIRRUS CONTINUE TO KEEP
MCLDY SKIES OVER THE NC FOOTHILLS AND NW PIEDMONT. THESE AREAS WERE
HIT PRETTY HARD WITH OUTFLOW FROM THE TSTM CLUSTER THIS MORNING AND
APPEAR TO HAVE BEEN KEPT STABLE BY THIS AND TO SOME EXTENT THE
CIRRUS. S AND W OF THIS AREA ISOLATED TSRA ARE STILL
EXPECTED...WHERE 1500-2000 J OF UNCAPPED SBCAPE IS SHOWN ON SPC
MESOANALYSIS. INDEED A COUPLE OF CELLS ARE STARTING TO GO UP OVER
PICKENS COUNTY. THE 12Z NCEP HIRES WINDOW RUNS REINFORCE SUGGESTIONS
OF NUMEROUS HRRR AND RAP RUNS THAT ISOLD ACTIVITY WILL KICK OFF IN
THE SMOKIES AND IN THE UPSTATE EAST OF SPARTANBURG. WITH THE
AFOREMENTIONED INSTABILITY AND EFFECTIVE BULK SHEAR OF 35-45
KT...ALONG WITH SUBSTANTIAL DCAPE OVER 1000 J/KG...STORMS WILL BE
QUITE CAPABLE OF DMGG WIND/HAIL. SVR WATCH JUST ISSUED FOR THE SRN
TIER OF THE NC MTNS/FOOTHILLS...THE UPSTATE AND NE GA.
HIGH PRESSURE BEGINS TO BUILD ACRS THE GREAT LAKES AND OHIO VALLEY
THRU TONIGHT. COLD FRONT CONTINUES TO BE PROGGED TO PUSH SWD THRU
MOST OF THE NC MTNS AND PIEDMONT BY DAYBREAK...PUSHING THROUGH THE
ERN SC PIEDMONT THEREAFTER. IN THE WAKE OF THE FRONT THINGS REMAIN
STABLE THROUGH THE DAY. HOWEVER...WITH A FAIRLY FLAT UPPER RIDGE
REMAINING OVER THE GULF STATES...THE FRONT DOES NOT APPEAR TO FULLY
IMPACT THE SAVANNAH RIVER VALLEY AND WRN UPSTATE. HOWEVER SUBSIDENCE
ALOFT APPEARS TO BE ENOUGH TO WEAKEN LAPSE RATES TO THE POINT THAT
ONLY LIMITED CONVECTION WILL BE POSSIBLE IN THIS AREA. GFS AND NAM
CONTINUE TO PRODUCE HEFTY SBCAPE VALUES OVER 1000 J/KG WEST OF
GSP...BUT SREF PROBS SUGGEST VALUES MOST LIKELY WILL NOT GET THIS
HIGH. I WILL INCLUDE A SCHC FOR DIURNAL SHWRS/TSTMS ALONG THE SRN
ESCARPMENT AND AREAS JUST SOUTH WHERE THE BEST INSTABILITY IS
SUGGESTED. HIGHS WILL BE NEAR NORMAL IN THE MORE CONTINENTAL AIRMASS
BUT WITH BRIGHT SUNSHINE.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
AS OF 230 PM FRIDAY...ONLY SUBTLE CHANGES ARE EXPECTED TO THE
OVERALL UPPER PATTERN FROM SUNDAY INTO MONDAY...MEANING WE SHOULD
REMAIN UNDER A NW FLOW ALOFT BUT THAT HEIGHTS SHOULD RISE A BIT AS
THE TROF OFF THE EAST COAST DEAMPLIFIES. THIS PATTERN WILL ALLOW THE
CENTER OF SURFACE HIGH PRESSURE TO MIGRATE FROM THE MIDWEST/OH
VALLEY REGION TO A POSITION OFF THE SOUTHEAST COAST ON SUNDAY. ONCE
THIS HAPPENS...WE CAN EXPECT SOME RETURN OF MOISTURE FROM THE SOUTH
AND SOME WEAK WARM ADVECTION. THAT WILL PUT THE WESTERN CAROLINAS
AND NE GEORGIA BACK INTO A REGIME WHERE MAINLY DIURNAL SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE. PRECIP CHANCES WERE LIMITED TO A
SLIGHT CHANCE ACROSS MOST OF THE AREA SUNDAY OWING TO THE LACK OF
DEVELOPMENT SEEN IN THE NAM...BUT THEN WERE ALLOWED TO GO UP TO A
CHANCE ACROSS MOST OF THE REGION MONDAY AS MOISTURE AND INSTABILITY
WERE INCREMENTALLY BETTER. TEMPS WILL CREEP UP A BIT FOR SUNDAY...
AND THEN RISE ABOUT A CATEGORY HIGHER FOR MONDAY...AROUND 80 IN THE
MTN VALLEYS AND MIDDLE 80S E OF THE MTNS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 145 PM FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
TUESDAY WITH THE PERSISTENT UPPER RIDGE ANCHORED OVER THE CENTRAL
CONUS AND AN EMBEDDED H5 LOW DRIFTING SLOWLY EASTWARD OVER THE
SOUTHERN PLAINS. SIMULTANEOUSLY...A CLOSED UPPER LOW IS EXPECTED TO
DROP DOWN OVER EXTREME NORTHERN NEW ENGLAND AND REMAIN OVER THAT
REGION FOR MOST OF THE PERIOD. IN TERMS OF THE SYNOPTIC PATTERN
EVOLUTION OVER OUR REGION...WE DONT EXPECT ANY SIG CHANGES THRU DAY
7 WITH THE DOMINANT UPPER RIDGE REMAINING IN PLACE THRU THE PERIOD.
AT THE SFC...WE BEGIN THE PERIOD UNDER LIGHT SLY FLOW WITH A TYPICAL
BERMUDA HIGH IN PLACE TO OUR EAST. EARLY IN THE DAY...A FAIRLY
ROBUST LOW DEEPENS OVER EXTREME NORTHERN NEW ENGLAND AND BRINGS A
SWATH OF COOLER AND DRIER AIR TOWARDS THE FCST AREA. THE MODELS
DIFFER ON HOW FAR SOUTH THIS LOW WILL MAKE WITH THE GFS BRINGING IT
QUITE A BIT FARTHER SOUTH THAN THE ECMWF AND CMC MODELS. I WILL
CONTINUE TO PUT MORE EMPHASIS ON THE ECMWF AND CMC SOLUTIONS FOR THE
TIME BEING AND THUS I DONT EXPECT THE COOLER/DRIER AIR TO PENETRATE
AS FAR SOUTH AS THE GFS SUGGESTS. ONCE THIS LOW MOVES WELL
OFFSHORE...ANOTHER CANADIAN HIGH TRIES TO PUSH SOUTHWARD AND INTO
THE REGION...HOWEVER ITS LOOKING LIKE IT WILL DISSIPATE FAIRLY QUICKLY
ONCE IT MAKES TO THE CAROLINAS.
AT ANY RATE...NO MAJOR CHANGES WERE NEEDED TO THE SENSIBLE FCST. I
DID INCREASE POPS OVER SOME PORTIONS OF THE CWFA TO SOLID CHANCE FOR
WIDELY SCT DIURNAL SHOWERS AND TS FOR WED AND THURS. OTHERWISE...I
CARRY A SLIGHT TO SOLID CHANCE FOR SH AND TS EACH DAY OF THE PERIOD.
IN ADDITION...IT IS TOO EARLY TO MENTION ANY THREAT OF SVR OR WELL
ORGANIZED CONVECTION AT THIS POINT. TEMPS SHOULD START OUT 5 TO 10
DEGREES ABOVE NORMAL FOR LATE MAY AND GRADUALLY DROP THRU THE PERIOD
WITH HIGHS RIGHT AROUND NORMAL BY NEXT FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...QUIET AVIATION CONDITIONS EXPECTED...AS DRY
AIR FILTERS IN ACRS THE REGION FROM THE NORTH. THE FRONT THAT PASSED
THRU FRIDAY WILL STALL JUST TO THE SOUTH OF KAND. GUIDANCE HINTS
THAT THERE MAY BE ENUF MOISTURE LINGERING FOR AT LEAST AN ISOLD SHRA
OR TSRA ACRS THE SW ESCARPMENT WEST OF KAVL/KGMU/KAND. THERE MAY NOT
EVEN BE MUCH IN THE WAY OF CUMULUS PER THE CAPPED FCST SNDGS. SO
GOING WITH JUST FEW-SCT CIRRUS WITH A LIGHT N TO NE WIND THRU
DAYBREAK. THEN WINDS WILL SHIFT OUT OF THE SE TO SW AND REMAIN LIGHT
THIS AFTN.
OUTLOOK...MOISTURE BEGINS TO RETURN SUNDAY...BRINGING BACK A BETTER
CHC OF AFTN SHRA/TSRA. AFTN CONVECTION COVERAGE IS EXPECTED TO
INCREASE SOMEWHAT FOR MONDAY AND TUESDAY...AS DEEPER MOISTURE
RETURNS.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/CDG/WIMBERLEY
SHORT TERM...PM
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1133 PM CDT FRI MAY 23 2014
.AVIATION...
NEXT BATCH OF SHOWERS AND THUNDERSTORMS IS SLOWLY MOVING THIS WAY
FROM EASTERN NEW MEXICO. BELIEVE THAT THE DHT TAF SITE WILL BE
AFFECTED BY THESE SHOWERS AND STORMS BETWEEN ABOUT 08Z AND 17Z. THE
SHOWERS AND STORMS MAY EVEN HOLD TOGETHER LONG ENOUGH TO AFFECT THE
AMA TAF SITE AS WELL...SO HAVE ADDED SOME SHOWERS WITH TEMPO TSRA
THERE AS WELL BETWEEN 11Z AND 18Z. THE GUY TAF SITE SHOULD REMAIN
CLEAR OF THE SHOWERS AND STORMS THIS GO AROUND. ALL SITES SHOULD
EXPERIENCE MVFR CIGS AND OR VISIBILITIES THROUGH ABOUT MID DAY ON
SATURDAY. CLOUDS SHOULD THEN LIFT INTO THE VFR RANGE. MORE SHOWERS
AND THUNDERSTORMS MAY FORM SATURDAY LATE AFTERNOON AND EVENING...BUT
AT THIS TIME IT IS UNCLEAR JUST HOW WIDESPREAD THEY WILL BE...SO WILL
LEAVE THE MENTION OF THEM OUT IN THE LATE PART OF THIS FORECAST.
SOUTHEAST WINDS WILL PREVAIL AT 15 KNOTS OR LESS AT THE TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 1058 PM CDT FRI MAY 23 2014/
UPDATE...
MAIN REASON FOR UPDATE WAS TO INCREASE POPS ACROSS THE WESTERN TEXAS
AND OKLAHOMA PANHANDLES AS CONVECTION MOVING ONTO THE EASTERN PLAINS
OF NEW MEXICO CONTINUES TO MOVE TO THE EAST.
PREV DISCUSSION... /ISSUED 654 PM CDT FRI MAY 23 2014/
AVIATION...
/00Z TAFS/ THE TERMINALS ARE CURRENTLY IN BETWEEN SHOWERS AND
THUNDERSTORMS IN OKLAHOMA AND OVER THE MOUNTAINS IN CENTRAL NEW
MEXICO. THE CONVECTION IN NEW MEXICO IS SLOWLY MOVING TO THE
NORTHEAST WHERE THE HRRR AND TTU WRF SUGGEST THIS CONVECTION ENTERING
THE SOUTHWEST TEXAS PANHANDLE...INCLUDING MOVING NEAR THE KAMA
TERMINAL BETWEEN 08-11Z. POSSIBLE FOR THESE STORMS TO MOVE NEAR THE
KAMA TERMINAL HOWEVER CONFIDENCE IN THIS OCCURRING IS NOT HIGH ENOUGH
TO INSERT -TSRA INTO THE FORECAST. IN FACT WHILE CONVECTION WILL
REMAIN PROBABLE THROUGH THE 24 HOUR FORECAST PERIOD...HAVE OPTED TO
NOT PUT IN A MENITON OF -TSRA IN ANY OF THE TERMINALS GIVEN THE
UNCERTAINTY ON WHERE AND WHEN THEY WILL IMPACT THE TERMINALS. OUTSIDE
OF THE RAIN POTENTIAL...LOW END VFR CONDITIONS WILL DETEORIRATE TO
LOW END MVFR OVERNIGHT. POSSIBLE FOR CIGS TO LOWER EVEN FUTHER TO IFR
AND WILL CONTINUE TO MONITOR FOR THAT POSSIBILITY.
ANOTHER CONCERN WILL BE THE POTENTIAL FOR FOG. LIGHT UPSLOPE
SOUTHEAST FLOW WILL DRAW IN GREATER BOUNDARY LAYER MOISTURE OVER
NORTH TEXAS /WHERE SFC DEWPOINTS ARE CURRENTLY IN THE LOW-MID 60S/.
THINK THE GREATER POTENTIAL FOR FOG WILL BE AT KAMA AS WINDS WILL BE
MORE OUT OF THE SOUTH THAN THE SOUTHEAST AT KGUY/KDHT LATE
TONIGHT/EARLY SAT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY.
CLK
PREV DISCUSSION... /ISSUED 356 PM CDT FRI MAY 23 2014/
DISCUSSION...
THROUGH TONIGHT: WE`VE SEEN A LULL IN THE RAIN THIS AFTERNOON IN MOST
PLACES AS STRONG SUBSIDENCE PREVAILS IN THE WAKE OF A DEPARTING
SHORTWAVE TROUGH. THE LULL MAY OR MAY NOT BE SHORT-LIVED AS
THUNDERSTORMS HAVE RAPIDLY DEVELOPED ALONG THE SANGRE DE CRISTO AND
SACRAMENTO MOUNTAINS IN CENTRAL NEW MEXICO. THANKS TO SOME CLEARING,
THE AIR MASS EAST OF THESE STORMS HAS RECOVERED FROM EARLY MORNING
CONVECTION WITH MIXED LAYER CAPE VALUES BETWEEN 1000 AND 1500 J/KG.
THEREFORE, THESE STORMS WILL LIKELY PERSIST AND INTENSIFY THIS
AFTERNOON AS THEY MOVE OFF THE MOUNTAINS. HOWEVER, AS THE CONVECTION
APPROACHES THE STATE LINE, IT WILL LIKELY LOSE ITS PUNCH SINCE THE
AIR MASS HAS NOT RECOVERED MUCH ACROSS THE WESTERN PANHANDLES.
NONETHELESS, SINCE THIS ACTIVITY IS MOUNTAIN-INDUCED, IT WILL
PROBABLY MAKE IT INTO THE WESTERN PANHANDLES AFTER 8 PM AND SLOWLY
SPREAD EASTWARD BEFORE DISSIPATING BY 3 AM. THINK THE HIGHEST
CHANCES FOR RAIN WILL BE WEST OF A BOISE CITY TO AMARILLO LINE.
SATURDAY-SUNDAY NIGHT: PROVIDED NO THUNDERSTORM COMPLEXES ROLL ACROSS
THE AREA TONIGHT OR SATURDAY MORNING, THE STAGE SHOULD BE SET FOR A
GOOD OPPORTUNITY FOR THUNDERSTORMS SATURDAY AFTERNOON THROUGH
SATURDAY NIGHT AS THE UPPER LOW SLOWLY MOVES OUR WAY. HEAVY RAIN IS
ALL BUT GUARANTEED SATURDAY EVENING AND NIGHT, ESPECIALLY WITH THE
STRONGER STORMS. THIS MAY CAUSE MORE FLOODING OR FLASH FLOODING
ISSUES. THE FLASH FLOODING THREAT WILL ONLY BE ENHANCED IF A
STATIONARY CONVECTIVE COLD POOL BECOMES ESTABLISHED AND ALLOWS
THUNDERSTORMS TO TRAIN OVER THE SAME AREA. A FEW SEVERE STORMS ALSO
APPEAR TO BE A GOOD BET BETWEEN 2 PM AND 11 PM AS LONG AS NO
OVERNIGHT THUNDERSTORM COMPLEXES OCCUR TONIGHT. MIXED LAYER CAPE
VALUES WILL AVERAGE AROUND 1500 J/KG TOMORROW AFTERNOON WITH DEEP
SHEAR VALUES INCREASING TO UP TO 30 KT BY LATE TOMORROW AFTERNOON
ACROSS THE WESTERN PANHANDLES. ORGANIZED MULTICELLS WILL BE THE
PREDOMINANT CONVECTIVE MODE, AND THEY WILL POSE A RISK FOR DAMAGING
WINDS AND LARGE HAIL. SUNDAY`S SEVERE POTENTIAL WILL HINGE GREATLY ON
HOW FAST CONVECTION DISSIPATES/MOVES OUT OF THE AREA LATE SATURDAY
NIGHT. IF THERE IS NO/VERY LITTLE PRE-CONVECTIVE CONTAMINATION
DURING THE MORNING AND EARLY AFTERNOON HOURS ON SUNDAY, A HEALTHY
RISK FOR SEVERE WEATHER LOOKS LIKELY, ESPECIALLY EAST OF AN ELKHART
TO HEREFORD LINE WHERE MIXED LAYER CAPE VALUES MAY EXCEED 2000 J/KG
AND DEEP LAYER SHEAR VALUES INCREASE UP TO 40 KT. HODOGRAPH PROFILES
AND THE COMBINATION OF THE BUOYANCY AND SHEAR SUGGEST THE POTENTIAL
FOR A MIXED CONVECTIVE MODE, INCLUDING SUPERCELLS. IF A DOMINANT
SUPERCELL DEVELOPS, AN ISOLATED TORNADO WILL BE POSSIBLE GIVEN
RELATIVELY LOW LCL HEIGHTS, MINIMAL LOW-LEVEL CIN, AND SUFFICIENT LOW-
LEVEL SHEAR (0-1 KM SHEAR VALUES AROUND 20 KT). HOWEVER, SUNDAY`S
SEVERE POTENTIAL WILL GREATLY DEPEND ON WHAT HAPPENS WITH CONVECTION
ON SATURDAY NIGHT.
MEMORIAL DAY-FRIDAY: ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED ON
MEMORIAL DAY, ESPECIALLY EAST OF AN ELKHART TO HEREFORD LINE. HEAVY
RAIN AND SEVERE WEATHER WILL REMAIN A DISTINCT POSSIBILITY AGAIN
DURING THE AFTERNOON AND EVENING HOURS. THUNDERSTORM CHANCES START
TO DECREASE FROM WEST TO EAST ON TUESDAY AS THE UPPER LOW BEGINS
SHIFT EAST OF THE AREA. HOWEVER, WITH THE DRYLINE REMAINING IN PLACE
THROUGHOUT THIS PERIOD, THE PATTERN WILL REMAIN FAVORABLE FOR
THUNDERSTORM CHANCES WEDNESDAY THROUGH FRIDAY, ESPECIALLY IF LIFTING
MECHANISM INTERACT WITH THE MOIST, MODESTLY UNSTABLE AIR MASS.
JACKSON
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH
FRIDAY AS EITHER RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE 20
PERCENT AND/OR 20-FOOT WINDS WILL REMAIN BELOW 15 MPH. WETTING RAINS
ARE EXPECTED TO CURB FUEL DRYNESS. THUNDERSTORMS ARE EXPECTED ALMOST
MOST DAYS...AND THEY COULD POSE A SMALL RISK FOR FIRE STARTS DUE TO
LIGHTNING.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
15/03
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
530 AM MST SAT MAY 24 2014
.UPDATE...TO AVIATION AND FIRE WEATHER DISCUSSIONS...
&&
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE MOVING EAST ACROSS THE DESERT
SOUTHWEST THIS WEEKEND. A SLIGHT CHANCE OF THUNDERSTORMS WILL BE
LIMITED MAINLY TO THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA THIS
AFTERNOON AND EVENING. ABOVE NORMAL TEMPERATURES WILL RETURN TO THE
REGION EARLY NEXT WEEK AS HIGH PRESSURE BECOMES REESTABLISHED TO OUR
SOUTH AND EAST.
&&
.DISCUSSION...
ERSTWHILE CUTOFF LOW CENTERED ACROSS CENTRAL AZ CONTINUES TO SLIDE
SLOWLY EASTWARD THIS MORNING. GFS AND ECMWF INDICATE THAT VORTICES
EMBEDDED WITHIN THE LARGER CYCLONIC CIRCULATION WILL CONTINUE TO
WEAKEN TODAY AS THE LOW FILLS AND LIFTS NORTHEASTWARD.
CONSEQUENTLY...FORCING FOR ASCENT WILL NOT BE QUITE AS STRONG AND
WILL BE CONCENTRATED WELL TO OUR EAST. NEVERTHELESS...MOISTURE
WRAPPING AROUND THE LOW WILL BE SUFFICIENT FOR ISOLATED
MOUNTAIN-BASED CONVECTION...MAINLY FOCUSED ACROSS NORTHEASTERN AZ.
LOCAL HI-RESOLUTION WRFS SUGGEST A FEW CELLS MAY WORK THEIR WAY INTO
THE PHOENIX AREA THIS AFTERNOON...THOUGH THIS IS GENERALLY NOT
SUPPORTED BY MOST OTHER GLOBAL AND CONVECTIVE-ALLOWING MODELS.
LATEST RUNS OF THE HRRR ARE ALSO NOT AS PROMISING FOR PRECIPITATION.
FORECAST POPS WERE LOWERED SLIGHTLY TO AROUND 10-15 PERCENT FOR THE
PHOENIX AREA BUT REMAIN AS HIGH AS 35 PERCENT ACROSS FAR EASTERN
GILA COUNTY.
AFOREMENTIONED UPPER LOW WILL BE LOCATED ACROSS SOUTHERN CO SUNDAY.
IN ITS WAKE...ISOLATED SHOWERS WILL REMAIN A THREAT ACROSS EASTERN
AZ. HOWEVER...FURTHER WEST A SUBSIDENT NORTHWESTERLY FLOW WILL
BECOME ESTABLISHED ACROSS CENTRAL AZ AND FORECAST POPS WERE LOWERED
TO AROUND 5 PERCENT FOR THE PHOENIX AREA. MEANWHILE...TEMPERATURES
WILL BE AROUND 5 DEGREES WARMER THAN THOSE OBSERVED SATURDAY.
WARMING TREND WILL CONTINUE THROUGH AT LEAST MIDWEEK AS A DRY
SOUTHWESTERLY FLOW DEVELOPS BETWEEN AN AREA OF LOW PRESSURE ACROSS
THE PACIFIC NORTHWEST AND A RIDGE ACROSS NORTHERN MEXICO. LATEST
GUIDANCE HAS TRENDED WARMER AND THIS IS REFLECTED IN THE
FORECAST...THOUGH TEMPERATURES WILL REMAIN WELL BELOW RECORDS.
WARMEST DAY LOOKS TO BE WEDNESDAY WITH HIGH TEMPERATURES REACHING
AROUND 106 DEGREES FOR PHOENIX...YUMA AND EL CENTRO. LATE NEXT
WEEK...GFS/ECMWF HINT AT SOME WEAK MOISTURE TRANSPORT FROM THE
EASTERN PACIFIC WHICH WOULD SUGGEST SOMEWHAT COOLER CONDITIONS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
LOW PRESSURE ALOFT WILL CONTINUE TO SLOWLY SHIFT EAST ACROSS AZ INTO
NM TODAY. MOISTURE WRAPPING AROUND THE BACKSIDE OF THE LOW WILL
PERSIST SCT-BKN SKIES ACROSS SOUTHEAST CA AND FEW-SCT CLOUDS FILLING
IN OVER SOUTH-CENTRAL AZ ALL AOA 12KFT. SUFFICIENT
MOISTURE/INSTABILITY ASSOCIATED WITH THE UPPER LEVEL LOW WARRANTS
KEEPING A SLIGHT CHANCE OF THUNDERSTORMS ACROSS SOUTH-CENTRAL AZ
THIS AFTERNOON/EVENING...MAINLY OVER THE HIGHER TERRAIN N AND E OF
PHOENIX. CURRENTLY HAVE NO MENTION...PREVAILING OR VICINITY...IN THE
12Z TAFS FOR KPHX...KIWA AND KSDL. HI-RES MODELS SUPPORT MTN
DEVELOPMENT IN THE LATE AFTERNOON...SO CHANCES OF ANYTHING ON THE
FRINGES OF THE METRO AREA SHOULD BE NEAR OR AFTER 25/00Z.
THUNDERSTORMS THAT FORM WILL HAVE THE POTENTIAL TO PRODUCE OUTFLOW
WINDS OF 40 KT AND BLOWING DUST/REDUCED VISIBILITY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
SLIGHT CHANCE FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL REMAIN OVER SOUTHERN GILA COUNTY AND AREAS WELL NORTH AND EAST
OF PHOENIX THROUGH MONDAY. WETTING RAINS ARE NOT LIKELY...WITH
STRONG GUSTY OUTFLOW WINDS AND LIGHTNING REMAINING THE PRIMARY
THREAT WITH STORM DEVELOPMENT. THE BEST MOISTURE AND INSTABILITY
PARAMETERS GREATLY DROP BY TUESDAY AS THE LOW FULLY EXITS THE FOUR
CORNERS AREA. RIDGING RETURNS TO THE SOUTHWEST...WARMING
TEMPERATURES AND KEEP SURFACE CONDITIONS DRY. DAYTIME HUMIDITY
PERCENTAGES FALLING INTO THE SINGLE DIGITS WITH MOSTLY FAIR
OVERNIGHT RECOVERIES POSSIBLE TUESDAY THROUGH THURSDAY. WINDS WILL
BE MOSTLY CALM...EXCEPT IN AND AROUND THUNDERSTORM DEVELOPMENT.
ANOTHER PACIFIC STORM SYSTEM IS FORECAST TO DEVELOP DOWN OVER THE
WEST COAST LATE NEXT WEEK...WHICH COULD SUPPORT INCREASING WINDS AND
HUMIDITY LEVELS AND SLIGHTLY COOLER TEMPERATURES FOR LATE NEXT
WEEKEND.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION....NOLTE
FIRE WEATHER...NOLTE/DEWEY
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
400 AM PDT SAT MAY 24 2014
.SYNOPSIS...WARMER TEMPERATURES INLAND THIS WEEKEND AS HIGH
PRESSURE BUILDS OVER THE AREA. NIGHT AND MORNING LOW CLOUDS WILL
CONTINUE TO BE PRESENT AT THE COAST. TEMPERATURES COOL TO NEAR
NORMAL EARLY NEXT WEEK.
&&
.DISCUSSION...AS OF 3:00 AM PDT SATURDAY...THE NORTHERLY GRADIENT
INCREASED QUICKLY YESTERDAY AFTERNOON INTO EVENING ERODING STRATUS
ALONG THE COAST. A SEPARATE STRATUS FIELD IS PUSHING SOUTH THIS
MORNING BUT WILL LIKELY ONLY IMPACT THE IMMEDIATE COAST. SATELLITE
IMAGERY OF THE LOW CLOUDS AS WELL AS VIEWING OF THE CAMELOPARDALID
METEOR SHOWER HAVE BEEN OBSCURED BY A LARGE AREA OF CIRRUS CLOUDS
MOVING THROUGH THE AREA.
THE UPPER LOW THAT BROUGHT SHOWERS AND THUNDERSTORMS TO THE AREA
EARLIER THIS WEEK CONTINUES TO SHIFT EAST ALLOWING A RIDGE TO
BUILD OVER THE EASTERN PACIFIC AND INTO NORTHERN CALIFORNIA. 850 MB
TEMPERATURES WARMED SIGNIFICANTLY TO 19C AT OAK BY 00Z YESTERDAY
AFTERNOON. TEMPERATURES ARE CURRENTLY RUNNING A FEW DEGREES ABOVE
WHERE THEY WERE AT THIS TIME YESTERDAY. NUMERICAL GUIDANCE HAS
THE AIRMASS CONTINUE TO WARM...REACHING A PEAK ON SUNDAY. WINDS
WILL REMAIN ONSHORE KEEPING THE HEAT FROM GETTING CLOSE TO THE
COAST HOWEVER. THE LATEST NAM HAS THE SFO-SAC PRESSURE GRADIENT UP
TO 5 MB BY 00Z THIS AFTERNOON WHICH SHOULD RESULT IN COOL
TEMPERATURES ALONG THE COAST AND GUSTY WINDS BY THIS AFTERNOON.
THUS THE WARMING TREND WILL MOSTLY BE FELT INLAND. HIGHS WILL
GENERALLY BE IN THE 60S AND 70S IN COASTAL AREAS TO MID 90S
INLAND TOMORROW AND SUNDAY.
EARLY NEXT WEEK A TROUGH DIGS SOUTH THROUGH THE PACIFIC NORTHWEST.
THE COOLER AIRMASS WILL BRING TEMPERATURES BACK TO NEAR SEASONAL
AVERAGES. THE INCREASE IN THE NORTHERLY PRESSURE GRADIENT SHOULD
SERVE TO ERODE STRATUS AWAY FROM THE COAST HOWEVER LEADING TO
INCREASED SUNSHINE IN COASTAL AREAS.
A BROAD TROUGH REMAINS THROUGH THE BALANCE OF WEEK WHICH WILL KEEP
TEMPERATURES MILD AND THE MARINE LAYER MIXED. IN THE EXTENDED BOTH
GFS AND ECMWF BRING A CLOSED LOW SOUTH INTO CALIFORNIA NEXT
WEEKEND. IF THIS SOLUTION VERIFIES IT COULD LEAD TO COOLER TEMPS
AND INCREASED INSTABILITY.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...MODERATE NORTHERLY FLOW
PUSHED STRATUS FIELD SOUTH...WITH LOW CLOUDS ONLY IMPACTING THE
MONTEREY BAY. CURRENT FORECAST MUCH MORE OPTIMISTIC COMPARED TO
PREVIOUS FORECAST. HIGH LEVEL CLOUDS MOVED OVER THE AREA...CURRENT
THINKING IS THAT THIS MAY PREVENT ANY LOW CLOUDS/FOG TO FORM IN
THE NORTH BAY...SO IT WAS COMPLETELY REMOVED FROM THE FORECAST.
LOW CLOUDS MAY STILL FORM ALONG SAN MATEO COAST...HOWEVER A
UNIFORM FIELD IS UNLIKELY TO IMPACT THE SF BAY. THE HRRR WAS THE
MAIN MODELS USED FOR THE FORECAST AS IT IS THE ONLY MODEL WHICH
SEEMED TO HAVE A GRASP ON THE CURRENT SITUATION.
VICINITY OF KSFO...PATCHY MVFR CIGS POSSIBLE BETWEEN 10Z AND 17Z.
LOW CONFIDENCE. MODERATE TO OCCASIONALLY STRONG ONSHORE WINDS
SATURDAY AFTERNOON...WITH GUSTS TO 30 KT AFTER 22Z. MODERATE
CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WILL BECOME IFR AROUND
10Z. LOW TO MODERATE CONFIDENCE.
&&
.MARINE...AS OF 8:10 PM PDT FRIDAY...NORTHERLY WINDS WILL INCREASE
THROUGH THE WEEKEND THROUGH MOST OF NEXT WEEK AS SURFACE HIGH
PRESSURE STRENGTHENS OVER THE EASTERN PACIFIC. THESE WINDS WILL
GENERATE STEEP FRESH SWELLS WHICH WILL BE PRESENT OVER THE WATERS
THROUGH AT LEAST FRIDAY OF NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 10 AM
SCA...PT ARENA TO PT REYES 10-60 NM
SCA...PT REYES TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PINOS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...MONTEREY BAY FROM 2 PM
SCA...SF BAY NORTH OF THE BAY BRIDGE FROM 2 PM
SCA...SF BAY SOUTH OF THE BAY BRIDGE FROM 2 PM
&&
$$
PUBLIC FORECAST: AC
AVIATION/MARINE: RILEY
VISIT US AT WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1132 AM EDT SAT MAY 24 2014
.SYNOPSIS...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BECOME FOCUSED OVER
WESTERN NEW ENGLAND THIS AFTERNOON...THEN SHOULD AFFECT MORE OF
SOUTHERN NEW ENGLAND SUNDAY. SUMMER LIKE WARMTH ON MEMORIAL DAY
WILL BE SHORT LIVED AS A STRONG BACK DOOR COLD FRONT MOVES THROUGH
THE REGION ON TUESDAY...BRINGING COOLER TEMPS ALONG WITH SCATTERED
SHOWERS/THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1130 AM UPDATE...
LOOKS LIKE HRRR IS ON TO SOMETHING WITH ITS DEPICTION OF W-E BAND
OF CONVECTION DROPPING S FROM NORTHERN NEW ENGLAND PER LATEST
RADAR MOSAIC. 12Z NAM STILL FOCUSES ON WESTERN NEW ENGLAND AS TO
GREATEST CONVECTIVE POTENTIAL THIS AFTERNOON BUT BASED UPON RADAR
TRENDS WOULD THINK MUCH OF REGION WILL SEE SCATTERED SHOWERS/
ISOLATED THUNDER LATER THIS AFTERNOON AND THIS EVENING.
INSTABILITY CERTAINLY LOOKS MEAGER WITH SB CAPES ON ORDER OF 500
J/KG OR SO AND LARGER SCALE LIFT IS RATHER WEAK...BUT COLD
TEMPERATURES ALOFT /-20C AT 500 MB/ COMBINED WITH DECENT MID LEVEL
LAPSE RATES SHOULD SUPPORT REDEVELOPMENT THIS AFTERNOON.
CLEARING HAS BEEN IN AND OUT ALONG S COAST AND SATELLITE LOOP
INDICATES THIS MAY BE CASE FOR MUCH OF AFTERNOON...WITH SOME
CLEARING PERHAPS WORKING INTO MORE OF SE MA. 13KM RAP HAS DECENT
HANDLE ON THIS SO MODIFIED CLOUD COVER TO REFLECT THIS THINKING.
NO OTHER CHANGES FROM EARLIER UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
** FEW STRONG THUNDERSTORMS WITH GUSTY WINDS AND SMALL HAIL
POSSIBLE ON SUNDAY ***
TONIGHT...
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS FAR WESTERN NEW
ENGLAND WIND DOWN BY LATE EVENING. OTHERWISE...MAINLY DRY FOR THE
REST OF THE NIGHT BESIDES A SPOT SHOWER OR TWO. LOW TEMPS WILL
MAINLY BE IN THE UPPER 40S AND LOWER 50S.
SUNDAY...
INTERESTING SETUP ACROSS SOUTHERN NEW ENGLAND AS THE NEXT SHORTWAVE
DIVES DOWN IN NORTHWEST FLOW ALOFT. THIS WILL COMBINED WITH STEEP
MID LEVEL LAPSE RATES ON THE ORDER OF 6.5 TO 7.0 C/KM...500 TO 1000
J/KG OF SURFACE BASED CAPE AND 30 TO 35 KNOTS OF 0 TO 6 KM SHEAR.
IN ADDITION...A SEA BREEZE FRONT MAY ACT AS A FOCUS FOR CONVECTION
ACROSS CENTRAL/EASTERN MA AND RHODE ISLAND.
OVERALL...THINK WILL SEE SCATTERED SHOWERS/THUNDERSTORMS DEVELOP
LATE SUNDAY MORNING/AFTERNOON WITH THE SHORTWAVE. GIVEN ABOVE
PARAMETERS...FEEL A FEW OF THE STRONGER STORMS MAY CONTAIN SMALL
HAIL/GUSTY WINDS AND HAVE ADDED ENHANCED WORDING TO THE FORECAST.
IN ADDITION...ALTHOUGH CAPE VALUES ARE LOWER THAN WE LIKE TO SEE FOR
SEVERE WEATHER...A BIT CONCERNED ABOUT 500 MB TEMPS BELOW -20C.
SOMETIMES THOSE COLD POOLS ALOFT CAN OVER PERFORM...SO AN ISOLATED
SEVERE THUNDERSTORM OR TWO CAN NOT BE RULED OUT ESPECIALLY NEAR THE
SEA BREEZE FRONT. FINALLY...THE THREAT WILL EXIST FOR LOCALLY HEAVY
RAINFALL/POOR DRAINAGE STREET FLOODING IF STORMS CAN TRAIN ALONG SEA
BREEZE BOUNDARY.
HIGH TEMPS SHOULD MAINLY BE IN THE 70S...EXCEPT 60S ON THE IMMEDIATE
COAST WITH SEA BREEZES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* WARM DAY MON FOLLOWED BY STRONG BACKDOOR COLD FRONT ON TUE
* ANY TSTMS LATE MON TO TUE PERIOD COULD HAVE STRONG WIND GUSTS
OVERVIEW...OVERALL UPPER AIR PATTERN AMPLIFIES DURING THIS TIME
PERIOD WITH CLOSED LOW SOMEWHERE S OR SE OF NEW ENGLAND BY END OF
WEEK...MORE REMINISCENT OF EARLY THAN LATE SPRING. HIGH CONFIDENCE
OF A STRONG BACKDOOR COLD FRONT MOVING THROUGH ON TUE BUT
UNCERTAIN WITH RESPECT TO TIMING. NW FLOW ALOFT REST OF WEEK.
ALTHOUGH LOOKS MAINLY DRY AFTER TUE...RISK OF SHORT WAVE ENERGY
EMBEDDED IN NW FLOW TRIGGERING ISOLATED AFTERNOON SHOWERS/TSTMS.
ONSHORE FLOW SHOULD KEEP EASTERN SECTIONS IN PARTICULAR ON COOL
SIDE. H50 TEMPS TURN COLDER LATE IN THE WEEK AND SET THE STAGE FOR
POSSIBLE AFTERNOON CONVECTION.
DETAILS...
MON...W OR EVEN WNW OFFSHORE AND DOWNSLOPING SURFACE FLOW AND H85 TEMPS
INCREASING TO AROUND 13C IN THE AFTERNOON SHOULD RESULT IN A VERY
WARM DAY WITH TEMPS PROBABLY REACHING MID TO UPPER 80S ACROSS MOST
OF AREA. EVEN THE CAPE SHOULD BE WARM WITH THIS FLOW. OPTED TO GO
SEVERAL DEGREES ABOVE MODEL CONSENSUS. BELIEVE SOUTHERN NEW
ENGLAND SHOULD REMAIN DRY THROUGH THE DAY...EXCEPT FOR A LOW
CHANCE OF TSTMS ALONG AND NE OF A MHT-BVY LINE LATE IN THE DAY AS
AIR MASS DESTABILIZES AHEAD OF BACKDOOR COLD FRONT ACROSS MAINE.
WIND SHEAR INCREASES AND ANY TSTMS THAT DO DEVELOP WOULD HAVE
POTENTIAL OF PRODUCING STRONG WIND GUSTS.
MON NIGHT...SOME RISK OF CONVECTION ESPECIALLY ALONG AND NE OF A
ORE-ORH-PYM-CQX LINE. ALTHOUGH NOT A DIURNALLY FAVORABLE TIME FOR
SURFACE BASED CONVECTION...STRONG WIND SHEAR AND MODERATELY
UNSTABLE MID LEVEL LAPSE RATES COULD YIELD ISOLATED STRONG/SEVERE
TSTMS. OTHERWISE...SHOULD BE A RELATIVELY WARM NIGHT WITH TEMPS
OVER MUCH OF THE REGION NOT DROPPING BELOW THE 60S.
TUE...THIS COULD BE A VERY INTERESTING DAY WITH DRAMATIC TEMP
CHANGES SPATIALLY AND TEMPORALLY...DEPENDENT UPON TIMING OF A
BACKDOOR COLD FRONT. FOR NOW...THINKING TEMPS WILL QUICKLY RISE TO
AT LEAST MID 70S E MA AND RI BEFORE CRASHING DURING THE AFTERNOON
WITH BACKDOOR COLD FRONT PASSAGE. MAY SEE DRAMATIC TEMP DROP IN
EASTERN MA AND RI FROM MID/UPPER 70S TO MID/UPPER 50S IN JUST AN
HOUR OR TWO. TEMPS MAY REACH MID/UPPER 80S CT VALLEY OF NH...MA
AND CT BEFORE DROPPING LATE IN THE DAY...WARMEST GREATER HARTFORD
AREA. LOW CONFIDENCE ON SHOWER/TSTM POTENTIAL. INSTABILITY
PARAMETERS SUGGEST RISK OF SHOWERS/TSTMS...BUT LOCATION AND
STRENGTH DEPENDENT UPON COLD FRONT TIMING. TOTAL TOTALS NEAR
50...K INDEX NEAR OR SLIGHTLY ABOVE 30...SHOWALTERS NEAR 0 AND MID
LEVEL LAPSE RATES AROUND 6.5 C/KM ALL POINT TO CHANCE TSTMS AND
POTENTIALLY RISK OF STRONG/SVR TSTMS GIVEN 0-6 KM VERTICAL SHEAR
OF 40-45 KT. WILL INDICATE CHANCE TSTMS GIVEN MODEL
SIGNAL...ALTHOUGH IT IS SOMEWHAT ATYPICAL TO HAVE A LOT OF
CONVECTION AHEAD OF A BACKDOOR FRONT IN EASTERN MA.
TUE NIGHT-THU NIGHT...ONSHORE FLOW SHOULD CAP MAX TEMPS NEAR THE
COAST GENERALLY IN MID 60S WITH LOW/MID 70S CT VALLEY REGION.
LOOKS TO BE MAINLY DRY THROUGH THIS PERIOD WITH ONSHORE FLOW AND
NO APPARENT FORCING.
FRI...SOME SUGGESTION OF COOLING 500 MB TEMPS WHICH COULD LEAD TO CHANCE
OF AFTERNOON SHOWERS/TSTMS. TEMPS LIKELY REMAINING NEAR TO
SOMEWHAT BELOW NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...MODERATE CONFIDENCE.
THROUGH THIS AFTERNOON...VFR CIGS AOA 050. SHOWERS DIMINISH
THROUGH MIDDAY WITH REDEVELOPMENT OF SCT SHRA/ISOLD TS OVER W NEW
ENGLAND...PRODUCING MVFR CONDITIONS.
TONIGHT AND SUNDAY...MAINLY VFR CONDITIONS EXPECTED. SCATTERED
SHOWERS/THUNDERSTORMS EXPECTED ACROSS THE REGION SUNDAY
AFTERNOON...BRINGING BRIEF LOCALIZED MVFR-IFR CONDITIONS. IN
ADDITION...THE STRONGEST STORMS MAY RESULT IN SMALL HAIL/GUSTY WINDS.
KBOS TAF...MODERATE CONFIDENCE. IFR LAYER HAS BEEN LURKING IN AREA
BUT TREND SEEMS TO BE A DIMINISHING ONE. AREAS OF MVFR CIGS IN
AREA SHOULD GIVE WAY TO MAINLY VFR BY LATE MORNING AND REMAIN VFR
THROUGH TONIGHT.
KBDL TAF...MODERATE CONFIDENCE. MVFR-VFR CONDITIONS IMPROVE TO
VFR BY LATE MORNING. LOW PROBABILITY OF AN ISOLATED THUNDERSTORM
GOING NEAR THE TERMINAL LATER THIS AFTERNOON/EVENING.
OUTLOOK...SUNDAY NIGHT THROUGH TUESDAY...
HIGH CONFIDENCE OF VFR SUNDAY NIGHT THROUGH MONDAY...EXCEPT
POSSIBLY AREAS OF MVFR CIGS/VSBYS IN VICINITY OF ANY TSTMS LATE
MON ACROSS S NH AND NE MA.
MONDAY NIGHT THROUGH TUESDAY....MODERATE CONFIDENCE OF PREVAILING
VFR CONDITIONS WITH AREAS OF MVFR CIGS/VSBYS IN SCT SHOWERS/TSTMS.
TUESDAY NIGHT...LOW CONFIDENCE OF MVFR-IFR CIGS BEHIND COLD FRONT.
WEDNESDAY...LOW CONFIDENCE OF MAINLY VFR WEST AND MVFR CIGS EAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...HIGH CONFIDENCE.
THROUGH THIS AFTERNOON...
NE WINDS GRADUALLY DIMINISH AS LOW PRES PASSES WELL SE OF WATERS.
DROPPED SCA ON NANTUCKET SOUND BUT WILL MAINTAIN IT FARTHER
OFFSHORE FOR COMBINATION OF 25KT WINDS AND 5 FT SEAS.
TONIGHT AND SUNDAY...
WINDS AND SEAS DIMINISH BELOW SCA THRESHOLDS EARLY THIS EVENING
ACROSS THE SOUTHERN ATLANTIC WATERS AS PRESSURE GRADIENT WEAKENS.
OTHERWISE...WINDS/SEAS WILL BE BELOW SCA CRITERIA TONIGHT AND
SUNDAY. WE MAY HAVE TO WATCH FOR A FEW STRONG THUNDERSTORMS ON
SUNDAY ACROSS THE NEAR SHORE WATERS...WITH GUSTY WINDS AND SMALL
HAIL.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
MODERATE CONFIDENCE OVERALL.
EXPECT WINDS AND SEAS TO REMAIN BELOW SCA CRITERIA THROUGH MON
NIGHT. HOWEVER...LOCALLY STRONG WIND GUSTS POSSIBLE IN VICINITY
OF ANY TSTMS LATE MON/MON NIGHT OVER COASTAL WATERS...MAINLY NORTH
OF PYM AND PVC. MORE SCT TSTMS WITH BRIEF STRONG WIND GUSTS
POSSIBLE OVER THE WATERS ON TUE. LOW CONFIDENCE OF A POSSIBLE
PERIOD OF NE WIND GUSTS TO 25 KT AND 3 TO 5 FT WIND WAVES BRIEFLY
BEHIND BACKDOOR COLD FRONT TUE AFTERNOON. ANTICIPATE WINDS AND
SEAS TO BE BELOW OR DROPPING BELOW SCA CRITERIA ON WEDNESDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
ANZ254>256.
&&
$$
SYNOPSIS...FRANK/THOMPSON
NEAR TERM...JWD
SHORT TERM...FRANK
LONG TERM...THOMPSON
AVIATION...JWD
MARINE...JWD
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1059 AM EDT SAT MAY 24 2014
.SYNOPSIS...
DISTURBANCES IN THE NORTHWEST FLOW ALOFT WILL MOVE ACROSS THE AREA
THIS WEEKEND. HIGH PRESSURE OVER THE OHIO VALLEY THEN PASSES TO
THE SOUTH ON MONDAY. A COLD FRONT WILL MOVE ACROSS THE REGION ON
TUESDAY...WITH CANADIAN HIGH PRESSURE RETURNING FOR THE REMAINDER
OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN UPPER LOW JUST SE OF THE AREA THIS MORNING WILL CONTINUE TO
TRACK EAST ACROSS THE WESTERN ATLANTIC...WITH GRADUAL HEIGHT RISES
TO EXPAND EASTWARD THIS WEEKEND AS A HIGH AMPLITUDE RIDGE OVER THE
MID SECTION OF THE COUNTRY BUILDS EAST. THIS WILL KEEP THE AREA IN
A NW FLOW ALOFT FOR THIS WEEKEND WITH WEAK TROUGHING EACH AFT.
LINGERING MOISTURE FROM THE SFC TO 700 MB AND WEAK INSTABILITY
WILL INTERACT WITH WEAK SHORT WAVES IN THE NW FLOW FOR SCT
SHOWERS AND ISOLATED THUNDERSTORMS. HRRR ADVERTISING A LINE OF
BROKEN SHRA/EMBEDDED CONVECTION DEVELOPING ACROSS CENTRAL NEW
ENGLAND LATE THIS MORNING IN RESPONSE TO A BACKSIDE SHORTWAVE SEEN
IN WV AND THEN ADVECTING SOUTH TOWARDS THE REGION LATE TODAY INTO
EVENING. THIS IS PLAUSIBLE...AND WILL REFLECT IN GRIDS IF RADAR
TRENDS BEAR OUT THROUGH THE EARLY AFTERNOON.
ISOLATED THUNDERSTORMS EXPECTED...PRIMARILY THIS AFT INTO EARLY
THIS EVE AND ACROSS NORTHERN AND WESTERN ZONES. SPC SSEO TARGETS
LOWER HUDSON VALLEY/NYC METRO/AND NE NJ AS HAVING BEST CHANCE OF
SEEING A THUNDERSTORM...WHICH MATCHES BEST EXPECTED AFT
INSTABILITY. SMALL HAIL AND HEAVY DOWNPOURS ARE POSSIBLE WITH THE
STRONGEST CONVECTION...BUT THE INGREDIENTS ARE NOT THERE FOR
SEVERE CONVECTION.
SOME BREAK OF SUN ALONG THE COAST THIS MORNING...BUT EXPECT
ABUNDANT CLOUD COVER THIS AFTERNOON WITH THE AFOREMENTIONED
MOISTURE IN PLACE. HIGHS WILL RANGE FROM THE MID 60S TO LOWER
70S...WARMEST ACROSS NE METRO NJ.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
UPPER TROUGH AXIS OFFSHORE CONTINUES TO BUILD EAST WITH GRADUAL HEIGHT
RISES. THIS WILL RESULT IN WARMER...DRIER WEATHER SUN INTO MON.
THERE MAY STILL BE AN ISOLATED SHOWER SUN AFT. HIGHS WILL BE THE
70S TO NEAR 80 ON SUN...WITH COASTAL LOCATIONS 75 TO 80 MON...AND
80 TO 85 INLAND. THIS IS ABOUT 10 DEGREES ABOVE NORMAL.
LOW PRESSURE DROPS SE ACROSS EASTERN CANADA AND INTO NORTHERN
NEW ENGLAND ON MON. THIS WILL KEEP THE AREA UNDER A MODERATE
W/SW FLOW...ALLOWING WARM CONDITIONS EVEN ALONG THE COAST AS THE
SEABREEZE IS KEPT IN CHECK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
EXPECT SCT SHOWERS/TSTMS ON TUE AS A COLD FRONT MOVES ACROSS
PERHAPS WITH A WEAK WAVE OF LOW PRES RIDING ALONG IT. SINCE THE
FLOW IS EXPECTED TO BE MORE PROGRESSIVE THAN THE GFS WOULD
SUGGEST...A DRIER AIRMASS SHOULD BUILD IN TUE NIGHT. A SHORTWAVE
DIVING DOWN THE BACK SIDE OF THE UPPER LOW COULD TRIGGER ISOLD
INSTABILITY SHOWERS ON WED. LOOKS TOO WARM ALOFT FOR THUNDER. THE
NORTHEAST WILL REMAIN IN A NW FLOW ALOFT WITH THE POTENTIAL FOR
RIDGE ROLLERS DURING THE SECOND HALF OF THE WEEK IF ANY PIECES OF
ENERGY RIDE OVER THE TOP OF THE RIDGE IN THE CENTRAL PART OF NOAM.
TEMPERATURES WILL START OFF ABOVE NORMAL LEVELS UNTIL THE COLD FRONT
MOVES ACROSS TUE NIGHT. NEAR NORMAL TEMPS ON WED...WILL SLOWLY CLIMB
BACK TO SLIGHTLY ABOVE NORMAL BY THE END OF THE WEEK.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
LOW PRESSURE SE OF NANTUCKET WILL CONTINUE TO TRACK OUT TO SEA
TODAY. WEAK HIGH PRESSURE BUILDS IN TONIGHT.
VARIABLE CONDITIONS FROM MVFR TO VFR THROUGH AROUND 18Z...THEN
GENERALLY VFR EXPECTED.
SCT SHRA AND ISOLD TSRA THEN POSSIBLE AFTER 18Z INTO THE EARLY
EVE. HIGHEST PROBABILITY FOR A TSRA FROM THE CITY N AND
W...HOWEVER THE PROBABILITY AND COVERAGE OF TSRA IS TOO LOW
HOWEVER TO INCLUDE IN THE TAFS.
N WINDS FOLLOWED BY SEA BREEZE DEVELOPMENT...ESPECIALLY THE
IMMEDIATE S COASTS. THE WIND SHIFT MAY NOT REACH KLGA. WINDS
BECOME LIGHT AND VARIABLE TONIGHT.
.OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...
.SUNDAY...MAINLY VFR. ISOLD SHRA POSSIBLE IN THE AFTERNOON.
.SUNDAY NIGHT-MONDAY NIGHT...VFR.
.TUESDAY...MAINLY VFR...EXCEPT IN SCT SHRA/TSRA.
.TUE NIGHT-WED...MAINLY VFR.
&&
.MARINE...
LOW PRES SE OF CAPE COD WILL CONTINUE TO TRACK AWAY FROM THE WATERS
TODAY. STRONGEST WINDS WILL BE ACROSS THE ERN ZONES. GFS RUNNING A
BIT HIGH ON THE WINDS...SO THE EXPECTATION IS THAT CONDITIONS WILL
REMAIN BELOW SCA LEVELS TODAY. HIGH PRES BUILDS IN FOR MON WITH WINDS
AND SEAS BELOW SCA LEVELS. SW WINDS INCREASE MON...WITH SCA CONDITIONS
POSSIBLE BY LATE IN THE DAY/EVE...PARTICULARLY ERN OCEAN. WINDS AND
SEAS COME DOWN FOR THE FIRST PART OF TUE...THEN A BACKDOOR COLD
FRONT PASSES LATE BRINGING A QUICK SHOT OF SCA POTENTIAL. WINDS AND
SEAS THEN SETTLE DOWN BEHIND THE FRONT FOR THE REST OF THE WEEK.
&&
.HYDROLOGY...
15 KT MEAN CLOUD LAYER FLOW WILL ALLOW FOR MORE MOVEMENT OF
CONVECTION THAN YESTERDAY...MINIMIZING THE MINOR URBAN/POOR
DRAINAGE FLOODING THREAT. THERE IS POTENTIAL FOR ISOLATED 1/2-3/4
INCH AMOUNTS WHERE ANY CONVECTION TRAINS THIS AFT/EARLY EVE.
NO SIGNIFICANT RAIN IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DW
NEAR TERM...NV/DW
SHORT TERM...DW
LONG TERM...24
AVIATION...MALOIT/JMC
MARINE...JMC
HYDROLOGY...DW/NV
AREA FORECAST DISCUSSION
NWS TAUNTON MA
930 AM EDT SAT MAY 24 2014
.SYNOPSIS...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BECOME FOCUSED OVER
WESTERN NEW ENGLAND THIS AFTERNOON...THEN SHOULD AFFECT MORE OF
SOUTHERN NEW ENGLAND SUNDAY. SUMMER LIKE WARMTH ON MEMORIAL DAY
WILL BE SHORT LIVED AS A STRONG BACK DOOR COLD FRONT MOVES THROUGH
THE REGION ON TUESDAY...BRINGING COOLER TEMPS ALONG WITH SCATTERED
SHOWERS/THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
930 AM UPDATE...
FEW SHOWERS STILL LINGERING ACROSS AREA THIS MORNING AS WEAK SHORT
WAVE ROTATES AROUND VERTICALLY STACKED LOW SE OF NEW ENGLAND WHICH
CAN BE SEEN ON WATER VAPOR IMAGERY.
HRRR CONTINUES TO SUGGEST THIS ACTIVITY WILL DIMINISH THROUGH
MIDDAY...BEFORE SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS DEVELOP
OVER WESTERN NEW ENGLAND DURING AFTERNOON. ALTHOUGH INSTABILITY IS
MARGINAL WITH SURFACE-BASED CAPES UNDER 1000 J/KG AND LARGER SCALE
LIFT ASSOCIATED WITH NEXT SHORT WAVE IS RATHER WEAK...COLD
TEMPERATURES ALOFT /-20C AT 500 MB/ COMBINED WITH DECENT MID LEVEL
LAPSE RATES SHOULD SUPPORT REDEVELOPMENT THIS AFTERNOON.
INTERESTING TO NOTE HRRR DEVELOPS MORE ACTIVITY OVER NORTHERN NEW
ENGLAND AND BRINGS IT S TO MA/NH BORDER EARLY THIS EVENING. NOT
SURE IF THAT WILL PAN OUT BUT SOMETHING WE WILL CONSIDER WITH
EARLY AFTERNOON UPDATE.
SOME CLEARING HAS WORKED ONTO S COAST BUT PER HIGH-RES MODELS THIS
SHOULD FILL IN BY MIDDAY.
NO OTHER CHANGES AT THIS TIME. HIGHS IN 50S ALONG IMMEDIATE COAST
WITH ONSHORE FLOW TO 60S ELSEWHERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
** FEW STRONG THUNDERSTORMS WITH GUSTY WINDS AND SMALL HAIL
POSSIBLE ON SUNDAY ***
TONIGHT...
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS FAR WESTERN NEW
ENGLAND WIND DOWN BY LATE EVENING. OTHERWISE...MAINLY DRY FOR THE
REST OF THE NIGHT BESIDES A SPOT SHOWER OR TWO. LOW TEMPS WILL
MAINLY BE IN THE UPPER 40S AND LOWER 50S.
SUNDAY...
INTERESTING SETUP ACROSS SOUTHERN NEW ENGLAND AS THE NEXT SHORTWAVE
DIVES DOWN IN NORTHWEST FLOW ALOFT. THIS WILL COMBINED WITH STEEP
MID LEVEL LAPSE RATES ON THE ORDER OF 6.5 TO 7.0 C/KM...500 TO 1000
J/KG OF SURFACE BASED CAPE AND 30 TO 35 KNOTS OF 0 TO 6 KM SHEAR.
IN ADDITION...A SEA BREEZE FRONT MAY ACT AS A FOCUS FOR CONVECTION
ACROSS CENTRAL/EASTERN MA AND RHODE ISLAND.
OVERALL...THINK WILL SEE SCATTERED SHOWERS/THUNDERSTORMS DEVELOP
LATE SUNDAY MORNING/AFTERNOON WITH THE SHORTWAVE. GIVEN ABOVE
PARAMETERS...FEEL A FEW OF THE STRONGER STORMS MAY CONTAIN SMALL
HAIL/GUSTY WINDS AND HAVE ADDED ENHANCED WORDING TO THE FORECAST.
IN ADDITION...ALTHOUGH CAPE VALUES ARE LOWER THAN WE LIKE TO SEE FOR
SEVERE WEATHER...A BIT CONCERNED ABOUT 500 MB TEMPS BELOW -20C.
SOMETIMES THOSE COLD POOLS ALOFT CAN OVER PERFORM...SO AN ISOLATED
SEVERE THUNDERSTORM OR TWO CAN NOT BE RULED OUT ESPECIALLY NEAR THE
SEA BREEZE FRONT. FINALLY...THE THREAT WILL EXIST FOR LOCALLY HEAVY
RAINFALL/POOR DRAINAGE STREET FLOODING IF STORMS CAN TRAIN ALONG SEA
BREEZE BOUNDARY.
HIGH TEMPS SHOULD MAINLY BE IN THE 70S...EXCEPT 60S ON THE IMMEDIATE
COAST WITH SEA BREEZES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* WARM DAY MON FOLLOWED BY STRONG BACKDOOR COLD FRONT ON TUE
* ANY TSTMS LATE MON TO TUE PERIOD COULD HAVE STRONG WIND GUSTS
OVERVIEW...OVERALL UPPER AIR PATTERN AMPLIFIES DURING THIS TIME
PERIOD WITH CLOSED LOW SOMEWHERE S OR SE OF NEW ENGLAND BY END OF
WEEK...MORE REMINISCENT OF EARLY THAN LATE SPRING. HIGH CONFIDENCE
OF A STRONG BACKDOOR COLD FRONT MOVING THROUGH ON TUE BUT
UNCERTAIN WITH RESPECT TO TIMING. NW FLOW ALOFT REST OF WEEK.
ALTHOUGH LOOKS MAINLY DRY AFTER TUE...RISK OF SHORT WAVE ENERGY
EMBEDDED IN NW FLOW TRIGGERING ISOLATED AFTERNOON SHOWERS/TSTMS.
ONSHORE FLOW SHOULD KEEP EASTERN SECTIONS IN PARTICULAR ON COOL
SIDE. H50 TEMPS TURN COLDER LATE IN THE WEEK AND SET THE STAGE FOR
POSSIBLE AFTERNOON CONVECTION.
DETAILS...
MON...W OR EVEN WNW OFFSHORE AND DOWNSLOPING SURFACE FLOW AND H85 TEMPS
INCREASING TO AROUND 13C IN THE AFTERNOON SHOULD RESULT IN A VERY
WARM DAY WITH TEMPS PROBABLY REACHING MID TO UPPER 80S ACROSS MOST
OF AREA. EVEN THE CAPE SHOULD BE WARM WITH THIS FLOW. OPTED TO GO
SEVERAL DEGREES ABOVE MODEL CONSENSUS. BELIEVE SOUTHERN NEW
ENGLAND SHOULD REMAIN DRY THROUGH THE DAY...EXCEPT FOR A LOW
CHANCE OF TSTMS ALONG AND NE OF A MHT-BVY LINE LATE IN THE DAY AS
AIR MASS DESTABILIZES AHEAD OF BACKDOOR COLD FRONT ACROSS MAINE.
WIND SHEAR INCREASES AND ANY TSTMS THAT DO DEVELOP WOULD HAVE
POTENTIAL OF PRODUCING STRONG WIND GUSTS.
MON NIGHT...SOME RISK OF CONVECTION ESPECIALLY ALONG AND NE OF A
ORE-ORH-PYM-CQX LINE. ALTHOUGH NOT A DIURNALLY FAVORABLE TIME FOR
SURFACE BASED CONVECTION...STRONG WIND SHEAR AND MODERATELY
UNSTABLE MID LEVEL LAPSE RATES COULD YIELD ISOLATED STRONG/SEVERE
TSTMS. OTHERWISE...SHOULD BE A RELATIVELY WARM NIGHT WITH TEMPS
OVER MUCH OF THE REGION NOT DROPPING BELOW THE 60S.
TUE...THIS COULD BE A VERY INTERESTING DAY WITH DRAMATIC TEMP
CHANGES SPATIALLY AND TEMPORALLY...DEPENDENT UPON TIMING OF A
BACKDOOR COLD FRONT. FOR NOW...THINKING TEMPS WILL QUICKLY RISE TO
AT LEAST MID 70S E MA AND RI BEFORE CRASHING DURING THE AFTERNOON
WITH BACKDOOR COLD FRONT PASSAGE. MAY SEE DRAMATIC TEMP DROP IN
EASTERN MA AND RI FROM MID/UPPER 70S TO MID/UPPER 50S IN JUST AN
HOUR OR TWO. TEMPS MAY REACH MID/UPPER 80S CT VALLEY OF NH...MA
AND CT BEFORE DROPPING LATE IN THE DAY...WARMEST GREATER HARTFORD
AREA. LOW CONFIDENCE ON SHOWER/TSTM POTENTIAL. INSTABILITY
PARAMETERS SUGGEST RISK OF SHOWERS/TSTMS...BUT LOCATION AND
STRENGTH DEPENDENT UPON COLD FRONT TIMING. TOTAL TOTALS NEAR
50...K INDEX NEAR OR SLIGHTLY ABOVE 30...SHOWALTERS NEAR 0 AND MID
LEVEL LAPSE RATES AROUND 6.5 C/KM ALL POINT TO CHANCE TSTMS AND
POTENTIALLY RISK OF STRONG/SVR TSTMS GIVEN 0-6 KM VERTICAL SHEAR
OF 40-45 KT. WILL INDICATE CHANCE TSTMS GIVEN MODEL
SIGNAL...ALTHOUGH IT IS SOMEWHAT ATYPICAL TO HAVE A LOT OF
CONVECTION AHEAD OF A BACKDOOR FRONT IN EASTERN MA.
TUE NIGHT-THU NIGHT...ONSHORE FLOW SHOULD CAP MAX TEMPS NEAR THE
COAST GENERALLY IN MID 60S WITH LOW/MID 70S CT VALLEY REGION.
LOOKS TO BE MAINLY DRY THROUGH THIS PERIOD WITH ONSHORE FLOW AND
NO APPARENT FORCING.
FRI...SOME SUGGESTION OF COOLING 500 MB TEMPS WHICH COULD LEAD TO CHANCE
OF AFTERNOON SHOWERS/TSTMS. TEMPS LIKELY REMAINING NEAR TO
SOMEWHAT BELOW NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...MODERATE CONFIDENCE.
THROUGH THIS AFTERNOON...VFR CIGS AOA 050. SHOWERS DIMINISH
THROUGH MIDDAY WITH REDEVELOPMENT OF SCT SHRA/ISOLD TS OVER W NEW
ENGLAND...PRODUCING MVFR CONDITIONS.
TONIGHT AND SUNDAY...MAINLY VFR CONDITIONS EXPECTED. SCATTERED
SHOWERS/THUNDERSTORMS EXPECTED ACROSS THE REGION SUNDAY
AFTERNOON...BRINGING BRIEF LOCALIZED MVFR-IFR CONDITIONS. IN
ADDITION...THE STRONGEST STORMS MAY RESULT IN SMALL HAIL/GUSTY WINDS.
KBOS TAF...MODERATE CONFIDENCE. IFR LAYER HAS BEEN LURKING IN AREA
BUT TREND SEEMS TO BE A DIMINISHING ONE. AREAS OF MVFR CIGS IN
AREA SHOULD GIVE WAY TO MAINLY VFR BY LATE MORNING AND REMAIN VFR
THROUGH TONIGHT.
KBDL TAF...MODERATE CONFIDENCE. MVFR-VFR CONDITIONS IMPROVE TO
VFR BY LATE MORNING. LOW PROBABILITY OF AN ISOLATED THUNDERSTORM
GOING NEAR THE TERMINAL LATER THIS AFTERNOON/EVENING.
OUTLOOK...SUNDAY NIGHT THROUGH TUESDAY...
HIGH CONFIDENCE OF VFR SUNDAY NIGHT THROUGH MONDAY...EXCEPT
POSSIBLY AREAS OF MVFR CIGS/VSBYS IN VICINITY OF ANY TSTMS LATE
MON ACROSS S NH AND NE MA.
MONDAY NIGHT THROUGH TUESDAY....MODERATE CONFIDENCE OF PREVAILING
VFR CONDITIONS WITH AREAS OF MVFR CIGS/VSBYS IN SCT SHOWERS/TSTMS.
TUESDAY NIGHT...LOW CONFIDENCE OF MVFR-IFR CIGS BEHIND COLD FRONT.
WEDNESDAY...LOW CONFIDENCE OF MAINLY VFR WEST AND MVFR CIGS EAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...HIGH CONFIDENCE.
THROUGH THIS AFTERNOON...
NE WINDS GRADUALLY DIMINISH AS LOW PRES PASSES WELL SE OF WATERS.
DROPPED SCA ON NANTUCKET SOUND BUT WILL MAINTAIN IT FARTHER
OFFSHORE FOR COMBINATION OF 25KT WINDS AND 5 FT SEAS.
TONIGHT AND SUNDAY...
WINDS AND SEAS DIMINISH BELOW SCA THRESHOLDS EARLY THIS EVENING
ACROSS THE SOUTHERN ATLANTIC WATERS AS PRESSURE GRADIENT WEAKENS.
OTHERWISE...WINDS/SEAS WILL BE BELOW SCA CRITERIA TONIGHT AND
SUNDAY. WE MAY HAVE TO WATCH FOR A FEW STRONG THUNDERSTORMS ON
SUNDAY ACROSS THE NEAR SHORE WATERS...WITH GUSTY WINDS AND SMALL
HAIL.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
MODERATE CONFIDENCE OVERALL.
EXPECT WINDS AND SEAS TO REMAIN BELOW SCA CRITERIA THROUGH MON
NIGHT. HOWEVER...LOCALLY STRONG WIND GUSTS POSSIBLE IN VICINITY
OF ANY TSTMS LATE MON/MON NIGHT OVER COASTAL WATERS...MAINLY NORTH
OF PYM AND PVC. MORE SCT TSTMS WITH BRIEF STRONG WIND GUSTS
POSSIBLE OVER THE WATERS ON TUE. LOW CONFIDENCE OF A POSSIBLE
PERIOD OF NE WIND GUSTS TO 25 KT AND 3 TO 5 FT WIND WAVES BRIEFLY
BEHIND BACKDOOR COLD FRONT TUE AFTERNOON. ANTICIPATE WINDS AND
SEAS TO BE BELOW OR DROPPING BELOW SCA CRITERIA ON WEDNESDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
ANZ254>256.
&&
$$
SYNOPSIS...FRANK/THOMPSON
NEAR TERM...JWD
SHORT TERM...FRANK
LONG TERM...THOMPSON
AVIATION...JWD
MARINE...JWD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
655 AM CDT Sat May 24 2014
...Updated aviation discussion...
.UPDATE...
ISSUED AT 655 AM CDT SAT MAY 24 2014
Have updated the forecast to include some patchy fog over far southwest
Kansas, generally along and west of Highway 23 from Dighton to Meade.
Some locally dense fog will be possible for an hour or so before the
the fog begins to burn off with daytime heating.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SAT MAY 24 2014
As the atmosphere destabilizes this afternoon the best instability
will be on the order of a couple of thousand J/kg located across
NW Kansas through central Kansas with less emphasis on the farther
western counties. Bulk shear values will be quite weak however. The
CAPE values will be owing largely to moisture as widespread low
level stratus will need to slowly erode this morning. With adequate
lift, a few rounds of shower and scattered thunderstorms will occur
again today as on Friday. The convective allowing models are not in
good agreement on the timing of convection as the 6Z runs are
indicating strongly forced convection between 00 and 06 UTC this
evening. The NAM solution expands what appeared to be the
aforementioned convection across the panhandles northward into
western Kansas later this morning associated with a isentropic lift
pattern. Initially we`ve maintained little if any POPS until around
18 z before ramping up chances through he afternoon and evening.
The current HRRR is not a tremendous help at this time as the
precipitation associated with the panhandles storm trends to
diminishing near Elkhart around 16 UTC. Beyond convective chances,
the highs will not be appreciably warmer than yesterday given the
expansive cloud cover. Another night of mild temperatures is
expected across central Kansas where temperature will not fall below
60 degrees, with stratus and potentially developing fog as
well.
.LONG TERM...(Sunday through Friday)
ISSUED AT 425 AM CDT SAT MAY 24 2014
The upper level low over the southwestern states today is progged by
the models to slowly move east into the Texas Panhandle by Memorial
Day. Weak disturbances rotating around this upper low will impact
the central High Plains through the weekend. Abundant low level
moisture will continue in place across the High Plains. This will
result in periods of scattered showers and thunderstorms through the
weekend, especially as the upper low and its associated colder air
aloft results in more destabilization. Hard to pin down the timing
on any specific disturbances but will at least show a diurnal trend
in precipitation chances.
Precipitation chances will continue off and on through Tuesday
before the upper low starts to move east out of the High Plains. By
midweek, an upper level ridge of high pressure will build into the
High Plains and push thunderstorm chances off to the south and east.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 655 AM CDT SAT MAY 24 2014
IFR to LIFR ceilings will persist through much of the morning before
lifting into the MVFR and VFR categories. Areas of fog around Garden
City will reduce visibilities to less than a mile for a few hours
this morning as well. Isolated light rainshowers will be possible
around Garden City and Dodge City late this morning with a chance
for thunderstorms developing early this evening.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 61 79 58 / 60 60 40 50
GCK 79 58 79 57 / 60 60 30 40
EHA 77 57 78 56 / 60 60 30 40
LBL 79 60 80 57 / 60 60 40 40
HYS 78 60 80 59 / 60 60 40 50
P28 80 63 78 62 / 60 60 40 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Gerard
SHORT TERM...Russell
LONG TERM...Gerard
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS TOPEKA KS
643 AM CDT Sat May 24 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 327 AM CDT SAT MAY 24 2014
Forecast for the next 24 hours remains mostly unchanged with a similar
environment seen for the past few days. Morning analysis shows the
upper trough responsible for this unsettled pattern rotating over
northern AZ with a broad upper ridge over the northern plains. A
series of embedded weak troughs were noted over the central plains.
One in particular across northern OK into southeast KS continues to
impact our CWA through the morning hours. A warm moist plume was
spreading northeast into southern and eastern Kansas as dewpoints
increase into the lower and middle 60s through the afternoon.
The increasing LLJ with the additional lift from the upper wave and
saturated atmospheric profile across northeast Kansas support the
current convection across southern portions of the area to continue,
if not increase in coverage through the morning and afternoon.
Activity is not expected to be severe through the day due to CAPE
values staying low near 1000 J/KG. Shear values, especially
directionally, increase a bit higher than yesterday in the 20 to 25
kt range with perhaps the stronger updrafts producing small hail and
gusty winds near 40 mph. The more pressing concern with convection
today will be the heavy rain. PWAT values increase to 1.6 inches
with mean h5 flow very weak suggesting slow-moving convection
generating outflow that triggers additional convection. The latest
NAM, GFS, ECMWF, and HRRR are similar in developing a heavier band
of rain impacting much of the area from now through at least 1 PM.
Areas near and south of Interstate 70 corridor stand the better
chances for flash flooding. A generous rainfall amount from 0.20 to
0.75 inches is likely with locally higher amounts from 1 to 2
inches with training convection. Likely precip chances decline to a
chance by this evening as guidance varies on if and where precip
redevelops from another weak upper wave.
Latest guidance was trending slightly cooler on temperatures today
due to extensive cloud cover and precip in the area. Lowered highs a
few degrees to the mid 70s but could still be too warm dependent on
precip coverage through the day. Lows this evening were unchanged in
the middle 60s.
.LONG TERM...(Sunday through Friday)
Issued at 327 AM CDT SAT MAY 24 2014
For Sunday through Tuesday, the forecast area is likely to remain
under the influence of the closed low to the west. Models are in
reasonably good agreement with the cut off low`s slow progression
east, and they maintain a conditionally unstable atmosphere with
decent moisture available and no real inhibition to convection.
With the occasional wave lifting out of the low providing some
forcing, scattered to numerous showers and thunderstorm should
develop. The forecast continues with POPs of 40 to 50 percent
during the daytime, mainly because there is no clear surface
feature to focus convection and pin point one location more likely
to receive precip over another. Deep layer sheer remains
unimpressive so organized severe weather looks unlikely. Really
with PWs near 1.5 inches, localized flash flooding remains the
main concern with the thunderstorm activity. Temps should not
change much from day to day since there is no real change in
airmass, so the temp forecast is generally a persistence forecast
of lows in the 60s and highs around 80.
By Wednesday, models are beginning to converge on an idea of the
closed upper low moving southeast gradually. Because of this the
forecast begins a trend down in POPs, but not completely doing
away with them. The GFS still suggests the atmosphere will be
conditionally unstable through the end of the week and that all is
needed might be some weak lift or weak forcing to generate precip.
Therefore some slight chances have been retained for Thursday and
Friday. Uncertainty is a bit higher for the end of the week since
the synoptic flow remains rather weak over the central plains.
This allows the GFS to bring a weak backdoor front into the area
while the ECMWF favors mid level ridging. Temps should see a
slight warming trend through the end of the work week due to
rising mid level heights and increases in insolation. However
strong warm air advection does not look to affect the area so
highs are forecast to warm into the mid 80s by Friday. Lows should
remain in the 60s.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 634 AM CDT SAT MAY 24 2014
Wide swath of SHRA is pushing northeast across KTOP/KMHK/KFOE with
visibilities being reduced occasionally to MVFR. Band of MVFR and
IFR cigs over central Kansas are edging close to KMHK and will
maintain lower cigs through 20Z. Lower confidence in MVFR cloud deck
impacting KTOP/KFOE as greater coverage in SHRA may restrict a
broken coverage. Low confidence forecast for the remainder of the period
as short term guidance varies on developing widely scattered TSRA
across the area in the afternoon and evening. Improved categories
to VFR with a mention of VCTS in case a storm develops near the
terminal.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...Bowen
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1058 AM CDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1045 AM CDT SAT MAY 24 2014
INITIAL WAA SHOWERS HAVE DIMINISHED OVER ARROWHEAD WITH REMNANT
CLOUDS THINNING. TRIMMED POPS THROUGH EARLY AFTERNOON BEFORE
POSSIBLE REDEVELOPMENT OVER BORDERLAND. LATEST HRRR 3KM SUGGESTS
VERY LITTLE ACTIVITY WHILE 12KM NAM IS MORE AGGRESSIVE WITH
CONVECTION. HAVE KEPT LOW POPS OVER ARROWHEAD/BORDERLAND FOR AFTN.
OTHERWISE RAISED MAX TEMPS BASED ON LATEST 92H TEMPS AND EXPECTED
SUNSHINE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT SAT MAY 24 2014
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE POTENTIAL
FOR SHOWERS AND STORMS...MAINLY ACROSS NE MN TODAY THROUGH
SUNDAY...AND THE ABOVE AVERAGE TEMPERATURES THIS HOLIDAY WEEKEND
WITH SLIGHTLY COOLER CONDITIONS AROUND THE IMMEDIATE LAKE SHORE.
DOMINATE SYNOPTIC FEATURE PRESENT ACROSS THE UPPER MIDWEST IN THE
FORM OF A HIGH AMPLITUDE UPPER RIDGE WITH AN ASSOCIATED WARM AIR
MASS AND SFC HIGH MOVING THROUGH THE GREAT LAKES. SOUTHERLY FLOW
ON THE WEST SIDE OF THE HIGH IS HELPING USHER IN THIS RELATIVELY
WARM AND HUMID AIR INTO THE NORTHLAND THIS WEEKEND. A WEAK/WWD
EXTENDING BRANCH OF THE SFC RIDGE WILL LINGER ACROSS NRN MN/WI
TODAY AND SUNDAY...AND SLIGHTLY DELAY THE APPROACHING SFC TROUGH
OVER THE PLAINS UNTIL MEMORIAL DAY. A COUPLE UPPER SHRT WVS WILL
RIDE ALONG THE NRN/NWRN EDGE OF THE UPPER RIDGE TODAY AND
TONIGHT...KICKING OFF LIGHT RAIN SHOWERS WITH POSSIBLY A FEW
ISOLATED WEAK STORMS. CURRENTLY THERE ARE A FEW RADAR RETURNS
SHOWING UP FROM BIG FALLS TO BRAINERD THIS MORNING ALONG A WEAK
BAND OF MID-LVL F-GEN...BUT THESE SHOWERS SHOULD DIMINISH IN
INTENSITY AND COVERAGE AS THEY MOVE EWD INTO THE DRIER AIR LATER
THIS MORNING.
ADDITIONAL SHOWERS AND ISOLATED STORMS COULD DEVELOP ALONG THE
INTERNATIONAL BORDER THIS AFTERNOON/EVENING TODAY AS THE BL
DESTABILIZES AND WEAK UPPER FORCING TRIGGERS CONVECTION ALONG AN
INSTABILITY GRADIENT ACROSS NRN MN. TEMPERATURES WILL WARM INTO
THE 70S AGAIN TODAY WITH A FEW LOWER 80S ACROSS NE MN. COOLER
CONDITIONS WILL BE FELT ALONG THE IMMEDIATE LAKE SHORE AREAS OF
LS. S/SW WINDS ACROSS LS THIS MORNING AND MOST OF THE AFTERNOON
WILL KEEP AREAS ALONG THE NORTH SHORE...NORTH OF SILVER BAY RATHER
CHILLY WITH MOST OF THE SOUTH SHORE WARMING UP INTO THE 70S.
HOWEVER...A WEAK NELY FLOW OVER THE HEAD OF THE LAKE COULD
POSSIBLY DEVELOP LATE THIS AFTERNOON AND INTO THE EVENING AND DROP
TEMPS AROUND DULUTH/SUPERIOR TO TWO HARBORS A QUICK 10 TO 15
DEGREES IN A SHORT PERIOD OF TIME. THE LAKE BREEZE WILL NOT HAVE
MUCH OF AN IMPACT ON INLAND AREAS...MAINLY JUST THE IMMEDIATE
LAKESHORE LOCATIONS.
ANOTHER LLJ IS EXPECTED TO DEVELOP TONIGHT AND ALLOW WEAK CONVECTION
TO PERSIST OVER FAR NRN/NERN MN. THE COVERAGE AND INTENSITY OF THE
SHOWERS/STORMS IS DIFFICULT TO DETERMINE AT THIS POINT...WITH THE
MAIN AREA OF PRECIP LIKELY HOLDING OFF TO THE WEST THROUGH SUNDAY
MORNING. THE ORIENTATION OF THE SFC HIGH AND APPROACHING TROUGH
FROM THE W/NW WILL KEEP THE WIND FLOW FROM THE SW AND PREVENT THE
DEVELOPMENT OF A STRONG LAKE BREEZE ON SUNDAY AS THE TROUGH
APPROACHES. TEMPERATURES WILL ONCE AGAIN WARM INTO THE 70S AND
LOWER 80S...WITH DWPTS RISING INTO THE 50S AND LOWER 60S.
CONDITIONS WILL FEEL MORE HOT AND HUMID ON SUNDAY WITH A BETTER
CHANCE OF SHOWERS AND STORMS IN THE AFTERNOON...ESPECIALLY OVER
THE WRN COUNTIES IN NE MN. T-STORMS ON SUN AFTERNOON COULD BECOME
STRONG THROUGH NE MN AS BL CAPE VALUES APPROACH 1000 J/KG AND A
MORE ROBUST SURGE OF MOIST AIR ARRIVES ALONG THE NOSE OF A STRONG
AREA OF MOISTURE TRANSPORT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 335 AM CDT SAT MAY 24 2014
SUNDAY NIGHT AND MONDAY A SHORTWAVE AND A SURFACE COLD FRONT WILL
DRAG ACROSS THE AREA...BRINGING A CHANCE FOR SHOWERS AND
THUNDERSTORMS. THE FRONT STALLS OVER THE AREA MONDAY NIGHT...AND
MAY SERVE AS THE FOCUS FOR MORE SHOWERS AND THUNDERSTORMS. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS IS SUNDAY NIGHT AND EARLY
MONDAY. TEMPERATURES THROUGH THE PERIOD TO REMAIN WARM WITH DEEP
MIXING ON MONDAY TO ALLOW TEMPERATURES TO RISE INTO THE UPPER 70S TO
AROUND 80...WHICH WILL BE A GOOD 10 DEGREES ABOVE NORMAL.
TUESDAY THROUGH FRIDAY THERE WILL BE A WEAK SEMI-CUT OFF UPPER LOW
IN THE SOUTHERN STREAM OF OUR SPLIT UPPER LEVEL FLOW THAT SLOWLY
WOBBLES EAST...THEN SOUTHEAST DURING THE WEEK. AN UPPER LEVEL RIDGE
BUILDS OVER THE MIDWEST IN THE NORTHERN STREAM DURING THE
WEEK...BRINGING WARM TEMPERATURES AND CHANCES FOR SHOWERS AND
THUNDERSTORMS TO THE FORECAST AREA ON AND OFF DURING THE WORK WEEK.
TEMPERATURES THROUGH THE WEEK WILL BE 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE PERIOD. HAVE MAINLY USED A CONSENSUS APPROACH TO THE
FORECAST...THOUGH IN GENERAL FAVOR THE ECMWF SOLUTION AND HAVE
ADJUSTED THAT DIRECTION FOR A FEW PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 635 AM CDT SAT MAY 24 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SOME -SHRA POSSIBLE
FOR KINL...KHIB AND KDLH THIS MORNING...BUT THEN DRY CONDITIONS
EXPECTED TO RETURN. LATE THIS AFTERNOON OR EVENING ISOLATED TSRA
MAY DEVELOP IN VICINITY OF KINL. CONFIDENCE IS NOT VERY HIGH SO
HAVE LEFT AS VCTS...SHIFTING TO VCSH AFTER 03Z AS POTENTIAL
LINGERS THERE MOST OF THE NIGHT. SOUTH WINDS TODAY TO INCREASE TO
10-12KTS FOR MUCH OF THE DAY...THEN DROPPING OFF AGAIN AROUND
SUNSET TO 4-8KTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 80 56 78 60 / 10 10 10 60
INL 83 59 81 57 / 20 20 40 70
BRD 82 58 80 62 / 10 10 50 70
HYR 79 52 80 61 / 0 10 10 60
ASX 79 51 78 59 / 10 0 10 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...BJT
LONG TERM...LE
AVIATION...LE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
710 AM CDT SAT MAY 24 2014
.SYNOPSIS...
ISSUED AT 337 AM CDT SAT MAY 24 2014
A STATIONARY FRONT CURRENTLY EXTENDS ACROSS NORTHERN OKLAHOMA AS A
CLOSED UPPER LOW EXISTS OVER ARIZONA. SCATTERED SHOWERS ARE LIFTING
NORTH ACROSS THE WESTERN SANDHILLS WITH A FEW SHOWERS IN CENTRAL
NEBRASKA. DEWPOINTS ACROSS WESTERN NEBRASKA ARE IN THE UPPER 50S.
SOME PATCHY FOG HAS ALSO DEVELOPED IN SOME AREAS ALTHOUGH VISIBILITIES
ARE CURRENTLY NO LOWER THAN 5SM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CDT SAT MAY 24 2014
ONLY A SLIGHT CHANCE FOR SHOWERS THROUGH MID MORNING WITH VERY
LITTLE FORCING TO INITIATE DEVELOPMENT. EXPECT PATCHY FOG OVER MOST
OF WESTERN NEBRASKA THIS MORNING TO END BY 15Z. THE LATEST KLBF
SOUNDING INDICATED PWAT OF 1.23 INCHES WHICH IS 180 PERCENT OF
NORMAL. AS THE UPPER LOW CONTINUES ITS SLOW EASTWARD PROGRESSION
INTO WESTERN NEW MEXICO...THE SLOW MOVEMENT WILL RESULT IN A SIMILAR
ENVIRONMENT OVER THE HIGH PLAINS TODAY. HIGHS TODAY REMAIN VERY NEAR
PREVIOUS FORECAST OF NEAR 75 DEGREES. EXPECT A CHANCE FOR
SHOWERS AND EMBEDDED THUNDER LATE THIS MORNING THROUGH THE AFTERNOON
WITH LOCALLY HEAVY RAIN POSSIBLE. COVERAGE REMAINS UNCERTAIN AS
INDICATED BY MODEL DIFFERENCES. THE HRRR MODELS SEEMS THE MOST IN
LINE WITH EXPECTED DEVELOPMENT TIED WITH DIURNALLY DRIVEN
ENVIRONMENT. IN FACT AFTER 00Z...POPS LIMITED TO A SLIGHT CHANCE
OVERNIGHT. ALSO A REPEAT OF PATCHY FOG IS FAVORABLE ACROSS CENTRAL
AND SOUTHEAST AREAS AFTER 09Z.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 337 AM CDT SAT MAY 24 2014
SUNDAY AND BEYOND. THE MAIN FORECAST CHALLENGE IN THE EXTENDED
CONTINUES TO BE PRECIPITATION CHANCES IN ASSOCIATION WITH A
STUBBORN UPPER LEVEL LOW ATOP THE DESERT SOUTHWEST. ON
SUNDAY...THE UPPER LOW WILL HAVE PROGRESSED TO THE FOUR CORNERS
REGION...BUT WILL CONTINUE TO MEANDER IN THE VICINITY OF THE
SOUTHERN ROCKIES THROUGH AT LEAST MIDDAY ON MONDAY. ANOTHER ROUND
OF PRECIPITATION IS ANTICIPATED FOR SUNDAY. THE HIGHEST CHANCE OF
POPS ARE ASSOCIATED WITH A WEAK SURFACE TROUGH THAT IS BISECTING
NORTHWESTERN NEBRASKA AND ACROSS OUR EASTERN ZONES WHERE
INSTABILITY IS ANTICIPATED TO BE HIGHEST. IT APPEARS ONCE AGAIN
THAT CONVECTIVE INHIBITION WILL BE WEAK ACROSS THE ENTIRE FORECAST
AREA...MULTIPLE CLUSTERS OF STORMS ARE EXPECTED. GIVEN THAT
FORECAST PWATS THROUGH THE AFTERNOON HOURS ARE ANTICIPATED TO BE
GREATER THAN 125% OR MORE OF AVERAGE...AND WITH STORM MOTIONS OF
15 KTS OR SO...DECENT RAINFALL AMOUNTS ARE POSSIBLE ONCE AGAIN.
FOR EARLY NEXT WEEK...THE UPPER LOW WILL RELUCTANTLY EJECT ONTO
THE SOUTHERN PLAINS...BUT SUFFICIENT FORCING AND MOISTURE REMAIN
FOR ADDITIONAL PRECIPITATION CHANCES. THE PLACEMENT OF THE UPPER
LOW WOULD FAVOR SOUTHEASTERN PORTIONS OF THE FORECAST AREA DURING
THE AFTERNOON HOURS MONDAY WHEN THE CAPPING INVERSION IS WEAKEST.
WILL MAINTAIN 40 PERCENT MENTION...BUT LIMIT THE OTHER PERIODS AT
SLIGHT CHANCE OR LESS. THE UPPER LOW CONTINUES TO MEANDER AND
SLOWLY FILL ACROSS THE SOUTHERN PLAINS THROUGH MIDWEEK AS A RIDGE
OF HIGH PRESSURE BUILDS ACROSS ROCKIES/CENTRAL CONUS.
PRECIPITATION CHANCES COME TO AN END FOR MOST LOCATIONS ON TUESDAY
AS THE RIDGE SHOULD SUPPRESS VERTICAL LIFT. THE DRY FORECAST
CONTINUES TO AT LEAST THURSDAY WHEN A BROAD TROUGH OF LOW PRESSURE
DEEPENS ACROSS THE WESTERN CONUS...THIS FORCES THE RIDGE EAST AND
ALLOWS FOR A RETURN TO SOUTHWESTERLY FLOW ATOP THE CENTRAL HIGH
PLAINS. WITH THE BUILDING RIDGE...TEMPERATURES WILL WARM BACK INTO
THE 80S FOR MOST IF NOT ALL LOCATIONS ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA THROUGH AT LEAST MID WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 710 AM CDT SAT MAY 24 2014
AT KLBF...IFR CEILINGS WILL IMPROVE TO MVFR BY 15Z AND VFR BY 18Z.
MODEL GUIDANCE SUGGESTS MVFR CEILINGS AND VISIBILITY RETURN BY
06Z/25TH. AT KVTN...MVFR CEILINGS ARE FORECAST TO BECOME VFR BY
18Z AND REMAIN VFR THROUGH THE END OF THE TAF PERIOD.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1011 AM CDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1011 AM CDT SAT MAY 24 2014
AFTER NUMEROUS CALLS TO EMERGENCY MANAGEMENT AND IMPACTED
SPOTTERS IN THE AREAS AFFECTED BY THE HEAVY RAINFALL YESTERDAY
(NORTHERN BULEIGH...KIDDER...AND EASTERN STUTSMAN
COUNTIES)...DECIDED TO CANCEL THE AREAL FLOOD WARNING AND AREAL
FLOOD ADVISORIES SINCE THERE ARE NO LONGER ANY FLOODING IMPACTS. IT
IS WORTH NOTING THAT THESE AREAS WILL HAVE MUCH LOWER FLASH FLOOD
GUIDANCE FOR THIS AFTERNOON AND EVENING`S CONVECTION.
OTHERWISE...DID NOT DEVIATE FROM THE PREVIOUS FORECAST FOR THIS
UPDATE. THE CURRENT RUN OF THE HRRR SHOWS SCATTERED THUNDERSTORMS
DEVELOPING SOUTH CENTRAL AROUND 19Z...THEN SLOWLY BECOMING MORE
NUMEROUS OVER WESTERN AND CENTRAL NORTH DAKOTA LATER THIS
AFTERNOON. WEAK WIND FLOW SHOULD ALLOW FOR SLOW STORM MOTIONS ONCE
AGAIN...WITH HEAVY RAIN BEING THE PRIMARY THREAT. THE FRESHENED UP
PRODUCTS HAVE BE SENT.
UPDATE ISSUED AT 640 AM CDT SAT MAY 24 2014
UPDATE TO BLEND THE POPS FOR THE REMAINDER OF THE DAY AND TONIGHT
TO THE 06 UTC LARGER SCALE DETERMINISTIC SUITE AND THE HIGH
RESOLUTION 08-09 UTC RAP/HRRR RUNS. OTHERWISE THE FORECAST REMAINS
ON TRACK WITH CONVECTIVE HAZARDS UNCHANGED FROM THE PREVIOUS
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT SAT MAY 24 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS STORM
COVERAGE/INTENSITY AND POTENTIAL FOR LOCALLY HEAVY RAINFALL
THROUGH TONIGHT.
IN THE NEAR TERM...THUNDERSTORMS HAVE RAPIDLY DIMINISHED WITH ONLY
A FEW LINGERING SHOWERS EARLY THIS MORNING IN WELLS AND FOSTER
COUNTIES. STORM REDEVELOPMENT IS EXPECTED BY MIDDAY WITH STORMS
INCREASING IN COVERAGE BY LATE AFTERNOON AND EVENING. WESTERN AND
NORTH CENTRAL COUNTIES ARE OUTLOOKED IN THE SPC 5 PERCENT RISK
AREA FOR A FEW MARGINALLY SEVERE STORMS. AM EXPECTING A SIMILAR
SCENARIO TO FRIDAY NIGHT...WITH RELATIVELY SLOW STORM MOVEMENTS...DECENT
INSTABILITY...BUT WEAK DEEP LAYER SHEAR. THREATS INCLUDE ISOLATED
LARGE HAIL...AND PERHAPS A FEW STRONG WIND GUSTS GIVEN THE STEEP
LOW LEVEL LAPSE RATES THROUGH EARLY EVENING. IN ADDITION...WILL LIKELY
HAVE A FEW LOCATIONS WITH SUBSTANTIAL RAINFALL AMOUNTS...AND WILL
HAVE TO MONITOR THE AREAS HIT HARD BY RECENT RAIN...ESPECIALLY
EASTERN STUTSMAN COUNTY. HAVE INCLUDED A MENTION OF HEAVY RAIN IN
THE FORECAST GRIDS. AFTERNOON HIGHS SHOULD REACH THE 80S AGAIN
MOST LOCATIONS. THE THREAT FOR MARGINALLY SEVERE STORMS WILL
CONTINUE THROUGH SATURDAY EVENING...WITH POTENTIAL FOR ADDITIONAL
HEAVY RAIN PERSISTING THROUGH THE OVERNIGHT HOURS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 346 AM CDT SAT MAY 24 2014
AN ACTIVE WEATHER PATTERN WITH NEAR DAILY CHANCES FOR
THUNDERSTORMS...POSSIBLY SEVERE...WILL HIGHLIGHT THE EXTENDED
FORECAST.
THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON A PROLONGED PERIOD
OF SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS UPSTREAM OF THE
CENTRAL CONUS UPPER LEVEL RIDGE AXIS. THIS SUPPORTS NEAR DAILY
CHANCES FOR CONVECTION ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
FOR SUNDAY A WEAK COLD FRONT/SURFACE TROUGH WILL PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. 1500-2000 J/KG OF ML CAPE IS
FORECAST ALONG AND AHEAD OF THE BOUNDARY ACROSS CENTRAL NORTH
DAKOTA WITH DEEP LAYER SHEAR OF 20-30 KTS...WHICH IS STRONGER THAN
THE AVAILABLE DEEP LAYER SHEAR ON FRIDAY AND SATURDAY. THUS...THE
THREAT FOR SEVERE HAIL AND WIND GUSTS WITH MORE ORGANIZED
CONVECTION IS HIGHER ON SUNDAY CENTRAL. CORFIDI VECTORS OF 10-15
KTS PROMOTES THE CONTINUED THREAT OF LOCALLY HEAVY RAIN WITH
THUNDERSTORMS WITH PWATS NEAR 1.25 INCHES. FOR MONDAY THROUGH
FRIDAY...HARD TO RULE OUT ANY SINGLE DAY WHERE AT LEAST A MARGINAL
THREAT FOR SEVERE WEATHER IS POSSIBLE GIVEN STRONGER UPPER LEVEL
FLOW UPSTREAM OF THE RIDGE AXIS AND GENERALLY SOUTHERLY LOW LEVEL
FLOW AHEAD OF LEE SURFACE TROUGHING TRANSPORTING SOUTHERN PLAINS
AND GULF OF MEXICO MOISTURE INTO THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 640 AM CDT SAT MAY 24 2014
ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS
AFTERNOON...BECOMING MORE NUMEROUS THROUGH THE LATE AFTERNOON AND
CONTINUING THROUGH THE EVENING AND NIGHT. ADDED TEMPO GROUPS OF
TSRA AT KDIK...KISN AND KBIS FOR FAVORED THUNDERSTORM THREAT
PERIODS...AND KEPT VCTS AT KMOT AND KJMS WHERE THUNDERSTORM TIMING
IS MORE UNCERTAIN. IFR CONDITIONS ARE POSSIBLE IN THUNDERSTORMS
WITH SMALL HAIL AND LOCALLY STRONG WINDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...RPK
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
744 AM EDT SAT MAY 24 2014
.SYNOPSIS...
HIGH PRESSURE OVR THE GRT LKS WILL SLOWLY BUILD SE ACROSS
PENNSYLVANIA THIS WEEKEND...THEN OFF THE MID ATLANTIC COAST ON
MEMORIAL DAY. A BACK DOOR COLD FRONT IS LIKELY TO PUSH SE THRU
CENTRAL PA LATE TUE OR WED...THEN STALL OUT ACROSS WESTERN PA THRU
MIDWEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW LVL MOISTURE TRAPPED BENEATH SUBSIDENCE INVERSION AND FORCED
TO ASCEND THE APPALACHIANS IS SUSTAINING A STRATOCU DECK ACROSS
THE CENTRAL MTNS EARLY THIS AM. LOWERING INVERSION HGT SHOULD
RESULT IN CLEARING SKIES LATER THIS MORNING...BTWN 10Z-14Z BASED
ON RAP SOUNDINGS AND LAMP GUIDANCE.
SHORTWAVE OVR SE ONTARIO AT 10Z IS SLATED TO DIVE SE ACROSS THE
REGION THIS AFTN. ALTHOUGH THIS FEATURE APPEARS TO BE
CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME RESPECTS...MIXED
LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED J/KG HIGHER...WITH
SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD ACROSS A GREATER
PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION. WILL KEEP
POPS IN THE 20-30 PCT RANGE.
MDL 8H TEMPS NR 9C SHOULD SUPPORT MAX TEMPS TODAY FROM THE U60S
OVR THE SPINE OF THE ALLEGHENIES...TO THE M70S ACROSS THE SUSQ
VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
ISOLD CONVECTION SHOULD DIE AND CU COLLAPSE THIS EVENING...AS
SHORTWAVE EXITS THE STATE AND SFC HIGH BUILDS IN. CLEAR SKY...LGT
WIND AND DRY AIR WILL RESULT IN A COOL NIGHT FOR LATE MAY WITH
MINS NEAR 40F ACROSS THE PERENNIAL COLD SPOTS OF THE NORTH...AND
MID 40S TO LOWER 50S HEADED SE TO THE LOWER SUSQ VALLEY. MDL SFC
RH FIELDS IMPLY PATCHY FOG IS POSSIBLE ARND DAWN IN THE VALLEYS
OF THE ALLEGHENIES.
RISING HGTS/WARMING TEMPS ALOFT SHOULD ENSURE A DRY SUNDAY.
ABUNDANT SUNSHINE AND ENS MEAN 8H TEMPS RISING TO NR 11C SHOULD
TRANSLATE TO HIGHS IN THE 70S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
SFC HIGH WILL DRIFT SE OF PA ON MEMORIAL DAY...USHERING IN A
WARMER RETURN SW FLOW. ALTHOUGH TEMPS ALOFT RISE...GEFS MAINTAINS A
RELATIVE PWAT MINIMUM OVR PA...INDICATING DRY WX AND PLENTY OF
SUNSHINE IS LIKELY. 8H TEMPS RISING TO NR 14C SHOULD SUPPORT HIGHS
FROM THE U70S OVR THE ALLEGHENY MTNS...TO THE M80S ACROSS THE SUSQ
VALLEY.
LG SCALE PATTERN IN MED RANGE MDLS SHOW A SHORTWAVE TRACKING NORTH
OF PA ON TUESDAY. WESTERLY LL JET/PLUME OF HIGHER PWATS AHEAD OF THIS
FEATURE WILL LIKELY PRODUCE SCT CONVECTION ACROSS PA ON TUESDAY.
IN THE WAKE OF THIS SYSTEM...SFC HIGH BUILDING ACROSS NEW ENG
APPEARS LKLY TO PUSH A BACKDOOR COLD FRONT SE ACROSS PA TUE
NIGHT/WED. AFTER A WARM TUESDAY...COOLER TEMPS/EASTERLY FLOW
APPEAR LIKELY OVR MOST OF CENTRAL PA WED/THU...WHILE STALLED
FRONTAL BNDRY ACROSS WESTERN PA COULD PROMOTE SCT DIURNAL
CONVECTION OVR THE W MTNS.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
INVERSION LOWERING AS HIGH PRESSURE IN LOWER LEVELS BUILDS INTO
THE REGION TODAY...BUT TRAPPED MOISTURE PRODUCING WIDESPREAD
STRATOCU DECK ACROSS THE WEST AND NORTH. THROUGH 14Z...MVFR
CONDITIONS EXPECTED FROM KAOO-KUNV-KIPT WITH IFR/LIFR FROM KBFD-
KJST...FOLLOWED BY MAINLY VFR CONDITIONS THE REMAINDER OF THE DAY
THROUGH MUCH OF TONIGHT.
COLDER AIR STILL IN PLACE ALOFT WILL PRODUCE PARTLY TO MOSTLY
SUNNY SKIES TODAY...WITH A SHORTWAVE SLIDING THROUGH THIS
AFTERNOON BRINGING AN INCREASE TO LAPSE RATES WHICH SHOULD
PROVIDE ENOUGH INSTABILITY TO GENERATE SCT SHOWERS AND ISOLATED
THUNDERSTORMS MAINLY IN THE EAST. PROB LESS THAN 30 PERCENT...SO
DID NOT MENTION IN TAFS ATTM.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.MON...VFR.
.TUE-WED...OCCASIONAL RESTRICTIONS IN SHOWERS AND POSS TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
606 AM EDT SAT MAY 24 2014
.SYNOPSIS...
HIGH PRESSURE OVR THE GRT LKS WILL SLOWLY BUILD SE ACROSS
PENNSYLVANIA THIS WEEKEND...THEN OFF THE MID ATLANTIC COAST ON
MEMORIAL DAY. A BACK DOOR COLD FRONT IS LIKELY TO PUSH SE THRU
CENTRAL PA LATE TUE OR WED...THEN STALL OUT ACROSS WESTERN PA THRU
MIDWEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW LVL MOISTURE TRAPPED BENEATH SUBSIDENCE INVERSION AND FORCED
TO ASCEND THE APPALACHIANS IS SUSTAINING A STRATOCU DECK ACROSS
THE CENTRAL MTNS EARLY THIS AM. LOWERING INVERSION HGT SHOULD
RESULT IN CLEARING SKIES LATER THIS MORNING...BTWN 10Z-14Z BASED
ON RAP SOUNDINGS AND LAMP GUIDANCE.
SHORTWAVE OVR SE ONTARIO AT 10Z IS SLATED TO DIVE SE ACROSS THE
REGION THIS AFTN. ALTHOUGH THIS FEATURE APPEARS TO BE
CONSIDERABLY WEAKER THAN FRIDAY/S IN SOME RESPECTS...MIXED
LAYER/MU CAPES SHOULD BE AT LEAST A FEW HUNDRED J/KG HIGHER...WITH
SIMILARLY STEEP MID LEVEL LAPSE RATES SPREAD ACROSS A GREATER
PORTION OF THE CWA.
SCATTERED...MAINLY AFTERNOON SHRA WITH ISOLATED TSRA LOOK TO BE A
GOOD BET AT THIS POINT FOR PRACTICALLY ANY LOCATION. WILL KEEP
POPS IN THE 20-30 PCT RANGE.
MDL 8H TEMPS NR 9C SHOULD SUPPORT MAX TEMPS TODAY FROM THE U60S
OVR THE SPINE OF THE ALLEGHENIES...TO THE M70S ACROSS THE SUSQ
VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
ISOLD CONVECTION SHOULD DIE AND CU COLLAPSE THIS EVENING...AS
SHORTWAVE EXITS THE STATE AND SFC HIGH BUILDS IN. CLEAR SKY...LGT
WIND AND DRY AIR WILL RESULT IN A COOL NIGHT FOR LATE MAY WITH
MINS NEAR 40F ACROSS THE PERENNIAL COLD SPOTS OF THE NORTH...AND
MID 40S TO LOWER 50S HEADED SE TO THE LOWER SUSQ VALLEY. MDL SFC
RH FIELDS IMPLY PATCHY FOG IS POSSIBLE ARND DAWN IN THE VALLEYS
OF THE ALLEGHENIES.
RISING HGTS/WARMING TEMPS ALOFT SHOULD ENSURE A DRY SUNDAY.
ABUNDANT SUNSHINE AND ENS MEAN 8H TEMPS RISING TO NR 11C SHOULD
TRANSLATE TO HIGHS IN THE 70S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
SFC HIGH WILL DRIFT SE OF PA ON MEMORIAL DAY...USHERING IN A
WARMER RETURN SW FLOW. ALTHOUGH TEMPS ALOFT RISE...GEFS MAINTAINS A
RELATIVE PWAT MINIMUM OVR PA...INDICATING DRY WX AND PLENTY OF
SUNSHINE IS LIKELY. 8H TEMPS RISING TO NR 14C SHOULD SUPPORT HIGHS
FROM THE U70S OVR THE ALLEGHENY MTNS...TO THE M80S ACROSS THE SUSQ
VALLEY.
LG SCALE PATTERN IN MED RANGE MDLS SHOW A SHORTWAVE TRACKING NORTH
OF PA ON TUESDAY. WESTERLY LL JET/PLUME OF HIGHER PWATS AHEAD OF THIS
FEATURE WILL LIKELY PRODUCE SCT CONVECTION ACROSS PA ON TUESDAY.
IN THE WAKE OF THIS SYSTEM...SFC HIGH BUILDING ACROSS NEW ENG
APPEARS LKLY TO PUSH A BACKDOOR COLD FRONT SE ACROSS PA TUE
NIGHT/WED. AFTER A WARM TUESDAY...COOLER TEMPS/EASTERLY FLOW
APPEAR LIKELY OVR MOST OF CENTRAL PA WED/THU...WHILE STALLED
FRONTAL BNDRY ACROSS WESTERN PA COULD PROMOTE SCT DIURNAL
CONVECTION OVR THE W MTNS.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
INVERSION LOWERING AS HIGH PRESSURE BUILDS INTO THE REGION
OVERNIGHT...BUT TRAPPED MOISTURE PRODUCING WIDESPREAD STRATOCU
DECK ACROSS THE WEST AND NORTH. MVFR CONDITIONS EXPECTED FROM
KAOO-KUNV-KIPT WITH IFR/LIFR DEVELOPING FROM KBFD-KJST. WINDS WILL
CONTINUE TO DECOUPLE AND RANGE BETWEEN 5-10 KTS AT THE SURFACE
THROUGH THE OVERNIGHT.
STRATOCU WILL MIX OUT BETWEEN 10-14Z AS WIDESPREAD VFR CONDITIONS
RETURN UNDER PARTLY TO MOSTLY SUNNY SKIES. COLDER AIR STILL IN
PLACE ALOFT ALONG WITH A SHORTWAVE SLIDING THROUGH AND INCREASING
LAPSE RATES FURTHER SHOULD PROVIDE ENOUGH INSTABILITY TO GENERATE
SCT SHOWERS AND ISOLATED THUNDERSTORMS MAINLY IN THE EAST DURING
THE AFTERNOON.
DRIER AIR AND GENERALLY PRECIPITATION-FREE CONDITIONS EXPECTED
FOR SUNDAY AND MONDAY WITH SURFACE RIDGING BUILDING IN.
.OUTLOOK...
.MON...VFR.
.TUE AND WED...AREAS OF RESTRICTIONS POSSIBLE IN SHOWERS AND
POSSIBLE TSRA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
936 AM CDT SAT MAY 24 2014
.AVIATION...
OVERNIGHT GUIDANCE HAS DONE A POOR JOB OVER NORTH
TEXAS...DEVELOPING MORNING CONVECTION THAT IS NOT OCCURRING. I
THINK THAT THE MCV MOVING NORTHEAST INTO THE PARIS AREA HAS
PRODUCED AN AREA OF WEAK SUBSIDENCE BEHIND IT...AND MORNING
SOUNDING AT FWD SHOWED NO DEEP AREAS OF INSTABILITY TO PRODUCE
CONVECTION. I WILL THEREFORE REMOVE THE MORNING VCTS. WATER VAPOR
SHOWS A WEAK DISTURBANCE NEAR THE RIO GRANDE/BIG BEND THAT SHOULD
MOVE ACROSS NORTH TX LATER THIS AFTERNOON...WHICH WILL LIKELY
HELP PRODUCE SOME SHOWERS WHEN COMBINED WITH DAYTIME HEATING.
THERE MAY BE SOME EMBEDDED THUNDER IN IT AS WELL...SO WILL
REINTRODUCE VCTS INTO THE TAFS AT 21Z. CONFIDENCE IN
LOCATION/TIMING IS LOW GIVEN THE POOR GUIDANCE...AND THE FORECAST
IS BASED MOSTLY ON THE MORNING SOUNDING AND WATER VAPOR
IMAGERY...PLUS THE FACT THAT 12Z NAM AND 13Z RAP DO APPEAR DRIER
THAN THEIR PREVIOUS RUNS. 84
&&
.PREV DISCUSSION... /ISSUED 344 AM CDT SAT MAY 24 2014/
A MCV /MESOSCALE CONVECTIVE VORTEX/ THAT WAS LOCATED JUST
SOUTHEAST OF STEPHENVILLE AT 3 AM WILL CONTINUE TO MOVE EAST
NORTHEAST TODAY. THE BEST CHANCES OF SHOWERS AND THUNDERSTORMS
WILL REMAIN ACROSS WEST TEXAS BUT WITH THE MCV MOVING ACROSS THE
REGION AND ADDITIONAL ACTIVITY FROM WEST TEXAS POSSIBLY MOVING
INTO THE WEST LATE THIS AFTERNOON...HAVE LEFT 20 TO 30 PERCENT
POPS ACROSS NORTH AND CENTRAL TEXAS FOR TODAY.
OTHERWISE...THE MAIN UPPER LEVEL LOW THAT WAS OVER WESTERN
ARIZONA AT 3 AM /08Z/ WILL MOVE SLOWLY NORTHEAST ACROSS NEW
MEXICO/SOUTHERN COLORADO TONIGHT THROUGH SUNDAY NIGHT AND INTO
OKLAHOMA/KANSAS BY TUESDAY MORNING. THIS SYSTEM IS THEN EXPECTED
TO SLOWLY FILL AND SINK SOUTHEAST WEDNESDAY AND THURSDAY. THE
MODELS CONTINUE TO HAVE PROBLEMS WITH HOW TO HANDLE THIS SYSTEM
COMING UP WITH VARYING SOLUTIONS MID TO LATE WEEK. THE OPERATIONAL
GFS WEAKENS THIS SYSTEM SO MUCH THAT IT BECOMES DIFFUSE BY THE END
OF THE WORK WEEK. THE ECMWF ON THE OTHER HAND INDICATES THAT THE
LOW WILL DRIFT ACROSS SOUTHEASTERN OKLAHOMA WEDNESDAY NIGHT AND
THEN SINK SOUTH AND THEN SOUTH SOUTHWEST ACROSS NORTHEAST AND
NORTH CENTRAL TEXAS BY FRIDAY NIGHT. NEEDLESS TO SAY...CONFIDENCE
ON THE EVOLUTION OF THE UPPER SYSTEM REMAINS LOW.
THE AREAL COVERAGE OF SHOWERS AND THUNDERSTORMS WILL START TO
INCREASE ON MEMORIAL DAY AS LARGE SCALE LIFT INCREASES AHEAD OF
THE UPPER LEVEL TROUGH. PRECIPITABLE WATER VALUES WILL RISE ABOVE
1.5 INCHES. WE WILL SEE THE POTENTIAL FOR LOCALLY HEAVY RAIN
MONDAY THROUGH TUESDAY NIGHT. SOME STRONG TO SEVERE STORMS WILL
BE POSSIBLE MAINLY ACROSS THE WEST MONDAY AND AREA WIDE TUESDAY.
RAIN CHANCES WILL CONTINUE WEDNESDAY AND THURSDAY THOUGH THE
BETTER CHANCES WILL SHIFT EASTWARD. THE RAIN CHANCES FOR FRIDAY
AND SATURDAY WILL DEPEND ON WHAT HAPPENS WITH THE UPPER LEVEL
LOW/TROUGH. HAVE ADDED 20 TO 30 PERCENT POPS FOR FRIDAY AND
SATURDAY BASED ON ECMWF SOLUTION.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 86 68 88 70 85 / 30 20 20 20 30
WACO, TX 85 67 87 69 84 / 20 20 20 20 40
PARIS, TX 82 65 85 66 82 / 40 10 20 20 30
DENTON, TX 84 67 85 68 82 / 30 20 20 30 30
MCKINNEY, TX 83 66 85 69 83 / 30 20 20 20 30
DALLAS, TX 85 69 87 70 84 / 30 20 20 20 30
TERRELL, TX 86 68 87 69 85 / 20 10 20 20 30
CORSICANA, TX 84 67 87 68 84 / 20 10 20 20 30
TEMPLE, TX 85 66 86 67 83 / 20 20 20 20 40
MINERAL WELLS, TX 85 64 86 68 82 / 30 20 30 40 40
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS TUCSON AZ
250 PM MST SAT MAY 24 2014
.SYNOPSIS...AN UPPER LOW OVER EASTERN ARIZONA WILL SLOWLY MOVE OVER
NEW MEXICO BY SUNDAY NIGHT THEN FURTHER EAST THEREAFTER. AS A RESULT
THERE IS A THREAT OF SHOWERS AND THUNDERSTORMS OVER MOST OF THE AREA
TONIGHT AND THEN MAINLY THE WHITE MOUNTAINS SUNDAY AND MONDAY. DRIER
WITH A PRONOUNCED WARMING TREND OCCURRING MONDAY THROUGH WEDNESDAY.
THEN A WEAK TROUGH COULD BRING SHOWERS AND THUNDERSTORMS TO THE
REGION AGAIN LATE IN THE WEEK.
&&
.DISCUSSION...NOT AS MUCH CONVECTION THIS AFTERNOON AS EARLIER
THOUGHT. HOWEVER WILL STILL SEE ISOLATED TO SCATTERED ACTIVITY EARLY
THIS EVENING MAINLY E OF TUCSON WITH BEST CHANCES IN THE MOUNTAINS.
ALL OF THIS IS ASSOCIATED WITH AN UPPER LOW THAT IS SLOWLY LIFTING
ENE ACROSS ERN AZ. WILL SEE A LULL AFTER SUNSET FOR MOST OF THE AREA
TO SAY ABOUT 2 AM BEFORE A DISTURBANCE ON BACK SIDE OF UPPER LOW
APPROACHES THE AREA FROM THE NW. LATEST RUNS OF THE HRRR AND RUC
INCLUDING THE 18Z NAM ARE DEVELOPING VERY LIGHT SHOWERS ACROSS PINAL
AND GRAHAM COUNTY WITH TUCSON ON THE SOUTHERN FRINGES.
UPPER LOW NEAR 4 CORNERS SUNDAY WITH WRAP AROUND MOISTURE ACROSS NE
AND E-CENTRAL AZ. ONCE AGAIN THE WHITES WILL BE THE BEST AREA FOR
STORMS SUNDAY AFTERNOON. ALTHOUGH THE AREA DRIES OUT ON MONDAY THERE
WILL STILL BE ENOUGH RESIDUAL MOISTURE AROUND FOR A SLIGHT CHANCE OF
STORMS IN THE WHITES. HIGHS SUNDAY WILL BE 2-7 DEGREES WARMER THAN
TODAY WITH ANOTHER 5-10 DEGREES OF WARMING ON MONDAY. UPPER RIDGE
AXIS WILL BE OVER THE STATE ON TUESDAY BRINGING THE RETURN OF TRIPLE
DIGIT HIGHS TO THE LOWER ELEVATIONS.
WEDNESDAY LIKELY THE WARMEST DAY OF THE WEEK WITH UPPER RIDGE AXIS
OVER NEW MEXICO AND AN UPPER LEVEL TROF OVER THE PACIFIC NORTHWEST.
THURSDAY AND FRIDAY...LOTS OF UNCERTAINTY FOR THESE TWO DAYS WITH
RESPECTS TO THE POTENTIAL FOR MID LEVEL CIRCULATION/MOISTURE VALUES
MOVING IN FROM THE S. OPERATIONAL GFS IS WETTER THAN OPERATIONAL
ECMWF. GFS/NOGAPS/CANADIAN ENSEMBLES ALSO WETTER THAN ECMWF.
ALTHOUGH CONFIDENCE IS VERY LOW FOR THESE TWO DAYS...I WENT AHEAD
AND INCREASED POPS JUST ENOUGH FOR MENTION OF SHOWERS TO SHOW UP IN
THE FORECAST FOR MOST OF THE AREA. HIGH TEMPERATURES ALSO
PROBLEMATIC ON THURSDAY. CASE IN POINT FOR TUCSON THE GFS BIAS
CORRECTED GOING WITH A HIGH OF 83...ECMWF BIAS CORRECTED SHOWING 93
WHILE CANADIAN BIAS CORRECTED SHOWING 100. AT THIS TIME ONLY LOWERED
THURSDAY HIGHS ONE DEGREE DUE TO THE LOW CONFIDENCE.
&&
.AVIATION...AN UPPER LOW EAST-CENTRAL ARIZONA CONTINUES TO SLOWLY
MOVE EAST. EXPECT ANOTHER ROUND OF MOSTLY ISOLD -SHRA MAINLY FROM
KTUS EWD AND NEAR MTNS THRU ABOUT 25/01Z WITH A SLIGHT CHC OF -TSRA.
THEREAFTER...THERE WILL BE A SLIGHT CHC OF -SHRA OVERNIGHT INTO
SUNDAY MORNING BUT COVERAGE WILL BE LIMITED. ANY STORMS WILL HAVE
SOME GUSTY WINDS. SCT-BKN CLOUDS MAINLY 10-12K FT AGL AND SCT-BKN
CLOUDS NEAR 25K FT AGL THRU SUNDAY MORNING. SFC WINDS WLY 10-15 KTS
WITH OCNL GUSTS UP TO 22 KTS BCMG TERRAIN DRIVEN LESS THAN 10 KTS
AFTER 25/02Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AS THE UPPER LOW SLOWLY MOVES EAST THIS AFTERNOON
THERE WILL BE ISOLATED SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS
FROM TUCSON EASTWARD. THERE IS A POTENTIAL FOR GUSTY WINDS NEAR ANY
STORMS. EXPECT THE SHOWERS AND STORMS TO TAPER OFF AFTER SUNSET BUT
ANOTHER DISTURBANCE ALOFT WILL STILL RESULT IN A SLIGHT CHANCE OF
SHOWERS OVERNIGHT INTO SUNDAY MORNING. BY SUNDAY AFTERNOON...THE
BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE ACROSS THE WHITE
MOUNTAINS AS THE LOW SLOWLY EXITS THE REGION TO THE EAST INTO
NORTHEAST NEW MEXICO AND THE TEXAS PANHANDLE ON MONDAY. THERE WILL
BE GUSTY NORTHWESTERLY WINDS ON THE BACKSIDE OF THE LOW IN THE UPPER
GILA RIVER VALLEY MONDAY WITH THE POTENTIAL FOR CRITICAL FIRE
WEATHER THRESHOLDS TO BE MET BRIEFLY MONDAY AFTERNOON NEAR SAFFORD.
OTHERWISE...PRONOUNCED WARMING TREND MONDAY THROUGH WEDNESDAY AS
RIDGING BUILDS OVER THE AREA. ANOTHER TROUGH WILL DEVELOP TO THE
SOUTHWEST OVER THE BAJA PENINSULA LATE IN THE WEEK FOR ANOTHER
POTENTIALLY ACTIVE PERIOD THURSDAY AND FRIDAY...BUT STILL QUITE A
BIT OF UNCERTAINTY WITH THE EXTENDED FORECAST.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
935 AM MST SAT MAY 24 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE MOVING EAST ACROSS THE DESERT
SOUTHWEST THIS WEEKEND. A SLIGHT CHANCE OF THUNDERSTORMS WILL BE
LIMITED MAINLY TO THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA THIS
AFTERNOON AND EVENING. ABOVE NORMAL TEMPERATURES WILL RETURN TO THE
REGION EARLY NEXT WEEK AS HIGH PRESSURE BECOMES REESTABLISHED TO OUR
SOUTH AND EAST.
&&
.DISCUSSION...
THE CENTER OF THE CUTOFF LOW CONTINUES TO MAKE GOOD EAST
NORTHEASTWARD PROGRESS WITH THE CURRENT LOCATION NOW OVER
EAST-CENTRAL ARIZONA. ALREADY STARTING TO SEE SOME CU DEVELOPMENT
ALONG THE MOGOLLON RIM AS OF 9 AM MST AND EXPECTING THIS TO EXPAND
OVER THE NEXT SEVERAL HOURS. COMPARED TO THE PAST TWO DAYS...SHOWER
AND THUNDERSTORM DEVELOPMENT SHOULD BE SCALED BACK DUE TO THE
WEAKENING UPPER LOW AND WARMING MID-LEVEL TEMPERATURES. ACTIVITY
TODAY WILL GENERALLY BE FOCUSED ACROSS THE HIGHER TERRAIN NORTH AND
EAST OF PHOENIX AS SUBSIDENCE FURTHER WEST WILL INHIBIT DEVELOPMENT
ACROSS AREAS THAT SAW STORMS THE PREVIOUS TWO DAYS. OUR CHANCE POPS
OVER SOUTHERN GILA COUNTY AND SLIGHT CHANCE THROUGH THE METRO
PHOENIX AREA SEEMS RIGHT ON TRACK. MOISTURE IS STILL FAIRLY
LIMITED...SO COVERAGE SHOULD BE FAIRLY ISOLATED. THERE WILL BE A
SMALL THREAT OF SOME GUSTY OUTFLOW WINDS TODAY...BUT WITH THE LACK
OF STRONG INSTABILITY...MOST STORMS WILL STRUGGLE TO REACH
SUFFICIENT HEIGHTS. THERE IS STILL SOME DOUBT ON WHETHER ANY STORMS
WILL REACH INTO THE LOWER DESERTS THIS AFTERNOON...BUT WITH A
NORTHWEST STEERING FLOW...ANY STORMS THAT DEVELOP IN SOUTHERN
YAVAPAI COUNTY COULD DRIFT INTO THE PHOENIX AREA BEFORE DYING.
&&
.PREVIOUS DISCUSSION...
ERSTWHILE CUTOFF LOW CENTERED ACROSS CENTRAL AZ CONTINUES TO SLIDE
SLOWLY EASTWARD THIS MORNING. GFS AND ECMWF INDICATE THAT VORTICES
EMBEDDED WITHIN THE LARGER CYCLONIC CIRCULATION WILL CONTINUE TO
WEAKEN TODAY AS THE LOW FILLS AND LIFTS NORTHEASTWARD.
CONSEQUENTLY...FORCING FOR ASCENT WILL NOT BE QUITE AS STRONG AND
WILL BE CONCENTRATED WELL TO OUR EAST. NEVERTHELESS...MOISTURE
WRAPPING AROUND THE LOW WILL BE SUFFICIENT FOR ISOLATED
MOUNTAIN-BASED CONVECTION...MAINLY FOCUSED ACROSS NORTHEASTERN AZ.
LOCAL HI-RESOLUTION WRFS SUGGEST A FEW CELLS MAY WORK THEIR WAY INTO
THE PHOENIX AREA THIS AFTERNOON...THOUGH THIS IS GENERALLY NOT
SUPPORTED BY MOST OTHER GLOBAL AND CONVECTIVE-ALLOWING MODELS.
LATEST RUNS OF THE HRRR ARE ALSO NOT AS PROMISING FOR PRECIPITATION.
FORECAST POPS WERE LOWERED SLIGHTLY TO AROUND 10-15 PERCENT FOR THE
PHOENIX AREA BUT REMAIN AS HIGH AS 35 PERCENT ACROSS FAR EASTERN
GILA COUNTY.
AFOREMENTIONED UPPER LOW WILL BE LOCATED ACROSS SOUTHERN CO SUNDAY.
IN ITS WAKE...ISOLATED SHOWERS WILL REMAIN A THREAT ACROSS EASTERN
AZ. HOWEVER...FURTHER WEST A SUBSIDENT NORTHWESTERLY FLOW WILL
BECOME ESTABLISHED ACROSS CENTRAL AZ AND FORECAST POPS WERE LOWERED
TO AROUND 5 PERCENT FOR THE PHOENIX AREA. MEANWHILE...TEMPERATURES
WILL BE AROUND 5 DEGREES WARMER THAN THOSE OBSERVED SATURDAY.
WARMING TREND WILL CONTINUE THROUGH AT LEAST MIDWEEK AS A DRY
SOUTHWESTERLY FLOW DEVELOPS BETWEEN AN AREA OF LOW PRESSURE ACROSS
THE PACIFIC NORTHWEST AND A RIDGE ACROSS NORTHERN MEXICO. LATEST
GUIDANCE HAS TRENDED WARMER AND THIS IS REFLECTED IN THE
FORECAST...THOUGH TEMPERATURES WILL REMAIN WELL BELOW RECORDS.
WARMEST DAY LOOKS TO BE WEDNESDAY WITH HIGH TEMPERATURES REACHING
AROUND 106 DEGREES FOR PHOENIX...YUMA AND EL CENTRO. LATE NEXT
WEEK...GFS/ECMWF HINT AT SOME WEAK MOISTURE TRANSPORT FROM THE
EASTERN PACIFIC WHICH WOULD SUGGEST SOMEWHAT COOLER CONDITIONS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
LOW PRESSURE ALOFT WILL CONTINUE TO SLOWLY SHIFT EAST ACROSS AZ INTO
NM TODAY. MOISTURE WRAPPING AROUND THE BACKSIDE OF THE LOW WILL
PERSIST SCT-BKN SKIES ACROSS SOUTHEAST CA AND FEW-SCT CLOUDS FILLING
IN OVER SOUTH-CENTRAL AZ ALL AOA 12KFT. SUFFICIENT
MOISTURE/INSTABILITY ASSOCIATED WITH THE UPPER LEVEL LOW WARRANTS
KEEPING A SLIGHT CHANCE OF THUNDERSTORMS ACROSS SOUTH-CENTRAL AZ
THIS AFTERNOON/EVENING...MAINLY OVER THE HIGHER TERRAIN N AND E OF
PHOENIX. CURRENTLY HAVE NO MENTION...PREVAILING OR VICINITY...IN THE
12Z TAFS FOR KPHX...KIWA AND KSDL. HI-RES MODELS SUPPORT MTN
DEVELOPMENT IN THE LATE AFTERNOON...SO CHANCES OF ANYTHING ON THE
FRINGES OF THE METRO AREA SHOULD BE NEAR OR AFTER 25/00Z.
THUNDERSTORMS THAT FORM WILL HAVE THE POTENTIAL TO PRODUCE OUTFLOW
WINDS OF 40 KT AND BLOWING DUST/REDUCED VISIBILITY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
SLIGHT CHANCE FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL REMAIN OVER SOUTHERN GILA COUNTY AND AREAS WELL NORTH AND EAST
OF PHOENIX THROUGH MONDAY. WETTING RAINS ARE NOT LIKELY...WITH
STRONG GUSTY OUTFLOW WINDS AND LIGHTNING REMAINING THE PRIMARY
THREAT WITH STORM DEVELOPMENT. THE BEST MOISTURE AND INSTABILITY
PARAMETERS GREATLY DROP BY TUESDAY AS THE LOW FULLY EXITS THE FOUR
CORNERS AREA. RIDGING RETURNS TO THE SOUTHWEST...WARMING
TEMPERATURES AND KEEP SURFACE CONDITIONS DRY. DAYTIME HUMIDITY
PERCENTAGES FALLING INTO THE SINGLE DIGITS WITH MOSTLY FAIR
OVERNIGHT RECOVERIES POSSIBLE TUESDAY THROUGH THURSDAY. WINDS WILL
BE MOSTLY CALM...EXCEPT IN AND AROUND THUNDERSTORM DEVELOPMENT.
ANOTHER PACIFIC STORM SYSTEM IS FORECAST TO DEVELOP DOWN OVER THE
WEST COAST LATE NEXT WEEK...WHICH COULD SUPPORT INCREASING WINDS AND
HUMIDITY LEVELS AND SLIGHTLY COOLER TEMPERATURES FOR LATE NEXT
WEEKEND.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...HIRSCH
AVIATION....NOLTE
FIRE WEATHER...NOLTE/DEWEY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
310 PM EDT SAT MAY 24 2014
.SYNOPSIS...
A FEW SHOWERS OR A THUNDERSTORM IS POSSIBLE THROUGH THIS EVENING...
MAINLY NORTH OF THE MASS PIKE. SCATTERED SHOWERS AND
THUNDERSTORMS SHOULD AFFECT MORE OF SOUTHERN NEW ENGLAND
SUNDAY...SOME OF WHICH COULD PRODUCE SMALL HAIL AND GUSTY WINDS. A
BACKDOOR COLD FRONT MOVES THROUGH NEW ENGLAND TUESDAY. ANOTHER
COLD FRONT MAY MOVE THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
315 PM UPDATE...
CONTINUING TO LEAN HEAVILY ON HRRR WHICH HAS BEEN DOING A GREAT
JOB WITH W-E LINE OF CONVECTION DROPPING S THROUGH NEW ENGLAND...
WHICH PUSHES THROUGH SW NH LATE THIS AFTERNOON AND PROBABLY
WEAKENING AS IT REACHES MASS PIKE CORRIDOR AROUND 6 PM...BEFORE
POSSIBLY REACHING S COAST AROUND 8 PM AS IT CONTINUES TO WEAKEN.
ADDITIONAL ACTIVITY MAY FIRE ACROSS W NEW ENGLAND BUT SHOULD BE
WIDELY SCATTERED IN NATURE.
NOT MUCH INSTABILITY PRESENT WITH ONLY FEW HUNDRED J/KG OF ML
CAPE...CERTAINLY BETTER INSTABILITY REMAINS TO OUR W ACROSS
UPSTATE NY WHICH SHOULD BE CASE THROUGH THIS EVENING. 0-6KM SHEAR
IS MINIMAL BUT MID LEVEL LAPSE RATES ARE DECENT CONSIDERING
PRESENCE OF COLD AIR ALOFT /-20C AT 500 MB/. SO IT IS POSSIBLE WE
SEE SOME EMBEDDED THUNDER AS THIS LINE DROPS S...BUT DO EXPECT IT
TO WEAKEN AS IT REACHES MASS PIKE CORRIDOR AND POINTS S.
ENDED UP BEING A GOOD AMOUNT OF CLEARING ON CAPE COD/ISLANDS AND
PARTS OF S COAST. EXPECT CLOUDS TO FILL BACK IN THIS EVENING AS
LOW LEVEL MOISTURE INCREASES WITH LIGHT ONSHORE FLOW.
ACTIVITY DIMINISHES TONIGHT LEAVING GOOD AMOUNT OF MID/HIGH CLOUDS
AROUND AREA ALONG WITH SOME PATCHY FOG. LOWS WILL DROP BACK INTO
40S/50S WHICH MATCHES MODEL CONSENSUS.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
*** FEW STRONG STORMS SUN WITH GUSTY WINDS/SMALL HAIL ***
STILL HAVE POTENTIAL FOR SOME STRONG STORMS TO DEVELOP SUN AS
SHORT WAVE PUSHES THROUGH NEW ENGLAND IN NW FLOW ALOFT. ALTHOUGH
INSTABILITY IS NOT OVERLY IMPRESSIVE WITH SB CAPES MAINLY UNDER
1000 J/KG...VERY COLD AIR ALOFT /-20C AT 500 MB/ WILL YIELD STEEP
MID LEVEL LAPSE RATES. THAT COMBINED WITH DECENT 0-6KM SHEAR OF
30-35KT MAY RESULT IN A FEW STRONG OR MARGINALLY SEVERE STORMS...
ESPECIALLY DURING AFTERNOON. FOCUS MAY END UP BEING NEAR SEA
BREEZE FRONT WHICH WOULD FAVOR LOCATIONS NEAR I-495 CORRIDOR SUN
AFTERNOON...BUT ADDITIONAL ACTIVITY MAY ALSO DEVELOP OUTSIDE OF
THESE AREAS ACROSS INTERIOR. CONVECTION MAY END UP DEVELOPING LATE
SUN MORNING IN FORM OF SCATTERED SHOWERS/ISOLATED THUNDER...BUT AM
MORE CONFIDENT MOST OF ACTIVITY WILL HOLD OFF UNTIL SUN AFTERNOON.
HIGHS SHOULD REACH WELL INTO 70S AWAY FROM COAST...WHERE ONSHORE
FLOW WILL KEEP TEMPERATURES IN 60S.
ACTIVITY WINDS DOWN SUN EVENING WITH LOSS OF DAYTIME HEATING...BUT
PRESENCE OF COLD AIR ALOFT MEANS PROCESS MAY BE SLOWER THAN WHAT
IS NORMALLY EXPECTED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
BIG PICTURE...
THE UPPER FLOW WILL FEATURE A BUILDING RIDGE OVER THE PLAINS...WITH
TROUGHS DIGGING ALONG EACH COAST. SHORTWAVES MOVING THROUGH THE
FLOW WILL AMPLIFY EACH TROUGH. THE FIRST SHORTWAVE CROSSING NEW
ENGLAND ARRIVES TUESDAY...THE SECOND ON FRIDAY OR SATURDAY. THIS
PATTERN WOULD ALLOW WARMER THAN NORMAL TEMPERATURES AT THE START OF
THE WEEK. AS THE UPPER TROUGH DIGS...THE PATTERN INDICATES
SEASONABLE OR SEASONABLY COOL TEMPS.
THE DAILIES...
MONDAY... WARM ADVECTION ALOFT WILL BRING CLOUDS MONDAY ESPECIALLY
IN SOUTHERN NH. THE FOCUS OF ISENTROPIC LIFT WILL BE ACROSS MAINE-NH-
VT...WITH MOST OF ANY SHOWERS TO OUR NORTH AND EAST. HOWEVER...IT
WILL BE CLOSE ENOUGH TO INDICATE CHANCE POPS IN SOUTHERN NH AND
NORTHEAST MASS. MAINLY DRY WEATHER WITH PLENTY OF SOLAR HEATING.
MIXING LEVELS WILL REACH AT LEAST 850 MB AND POSSIBLY A LITTLE
HIGHER. TEMPS AT 850 MB WILL BE 12-14C...SO MAX TEMPS HAVE A
POTENTIAL TO REACH THE LOW TO MID 80S. WINDS IN THE MIXED LAYER
WILL REACH 20-25 KNOTS...SO EXPECT WIND GUSTS IN THAT RANGE.
TUESDAY-WEDNESDAY... UPPER SHORTWAVE SWEEPS SOUTHEAST ACROSS NEW
ENGLAND...AND WILL DRIVE A COLD FRONT ACROSS OUR AREA. THE GFS AND
ECMWF SHOW SIMILAR TIMING WITH FROPA MID MORNING TO EARLY AFTERNOON.
WHATEVER THE EXACT TIMING...THIS SUGGESTS A PERIOD OF CLOUDS AND
CHANCE OF SHOWERS AS THE FRONT MOVES THROUGH ON TUESDAY. STABILITY
IS MARGINAL WITH 850-500 MB LAPSE RATE 6-6.5C/KM AND TOTALS UPPER
40S TO AROUND 50. COULD BE A COUPLE OF TSTMS ALONG THE FRONT. ALSO
SIGNS OF AN ABRUPT TEMPERATURE CHANGE AFTER FROPA AS WINDS WILL
BECOME NORTHEAST. MAX TEMPS WILL LIKELY BE PRIOR TO FROPA AND THE
GREATEST COOLING AFTER PASSAGE WILL BE IN EASTERN MASS. WE HAVE
MAINTAINED WARMEST MAX TEMPS IN THE CT VALLEY WITH VALUES NEAR
80...AND VALUES 70-75 IN EASTERN MASS. WEDNESDAY WILL BE A QUIETER
DAY WITH SOME CUMULUS DEVELOPMENT AND CONTINUED EAST TO NORTHEAST
WINDS.
THURSDAY-FRIDAY-SATURDAY...
OVERVIEW...THIS PORTION OF THE FORECAST IS STILL DOMINATED BY
NORTHERN STREAM FLOW AND AN AREA OF UNSTABLE AIR CONTAINED WITH
UPPER LEVEL LOWS OVER SOUTHEASTERN CANADA.
MODEL DISCREPANCIES EXIST IN THE HANDLING OF THE ENERGY COMING DOWN
INTO THE REGION FOR FRIDAY. THE ECMWF HAS A STRONGER AREA OF
VORTICITY THAN THE GFS AND IS FURTHER SOUTH THAN THE GFS.
HOWEVER...BOTH SEEM TO FORCE THE SHOWERS ALONG A COLD FRONT. HAVE
GONE WITH A MODEL BLEND TO HANDLE THIS EXCEPT FOR THE CMC WHICH
SEEMS TO BE AN OUTLIER.
THURSDAY...SOME ENERGY AROUND DURING THIS PERIOD ALLOWS FOR SOME
PRECIPITATION IN NORTHERN AND WESTERN NEW ENGLAND BUT THAT IS AS FAR
AS THEY COME DURING THE DAY. HAVE STILL ALLOWED FOR CLOUDS DURING
THE DAY ON AN EASTERLY SURFACE FLOW. A SLIGHT CHANCE OF SHOWERS IS
POSSIBLE OVERNIGHT INTO FRIDAY AHEAD OF THE PIECE OF ENERGY THAT
MOVES INTO THE REGION FROM THE NORTHWEST. INSTABILITY INDEXES SHOW A
POSSIBILITY OF THUNDER WITH THE TOTAL OF TOTALS MAINLY BETWEEN 40
AND 50 WITH PATCHES OF 50 AROUND.
FRIDAY AND SATURDAY...RAIN CONTINUES FROM THE OVERNIGHT HOURS INTO
THE DAY. A HIGH PRESSURE SYSTEM BEHIND THE FRONT SHOULD ALLOW FOR A
FRONTAL PASSAGE AND CLEARING FOR SATURDAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH SUNDAY NIGHT...MODERATE CONFIDENCE.
BAND OF SHOWERS/ISOLD TSTMS WITH MVFR CIGS/VSBYS WILL DROP S
ACROSS NEW ENGLAND THROUGH THIS EVENING...PROBABLY REACHING AS FAR
AS KBAF-KORH-KBOS BEFORE WEAKENING. ADDITIONAL SCT SHOWERS/ISOLD
TSTMS MAY DEVELOP NEAR BERKSHIRES THROUGH SUNSET. OTHERWISE VFR
CIGS AOA 050 THROUGH TONIGHT...EXCEPT AROUND CAPE COD AND ISLANDS
WHERE PERIOD OF MVFR CIGS SHOULD OCCUR TOWARD DAYBREAK.
ANOTHER ROUND OF SCT SHOWERS/TSTMS EXPECTED SUN WITH MVFR/IFR
CONDITIONS...PRIMARILY ACROSS INTERIOR. ACTIVITY MAY BECOME
FOCUSED ALONG SEA BREEZE FRONT AROUND MIDDAY WHICH SHOULD EXTEND
NEAR KASH-KBED-KTAN CORRIDOR. SOME STORMS COULD PRODUCE SMALL HAIL
AND BRIEF WIND GUSTS TO 35KT. ACTIVITY SUBSIDES SUN EVENING WITH
VFR CONDITIONS EXPECTED.
KBOS TAF...MODERATE CONFIDENCE. MVFR POSSIBLE 21Z-23Z AS BAND OF
SHOWERS/ISOLD TSTMS DROPS S. HIGH CONFIDENCE IN SEA BREEZE SUN.
KBDL TAF...MODERATE CONFIDENCE. LOW PROBABILITY OF ISOLD TSTM LATE
THIS AFTERNOON BUT ACTIVITY SHOULD REMAIN FARTHER W.
OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
GENERALLY VFR. PERIOD OF MVFR CIGS/VSBYS POSSIBLE TUESDAY IN
SHOWERS/SCATTERED TSTMS AS A COLD FRONT MOVES THROUGH. WEST WINDS
MONDAY AND EARLY TUESDAY WILL SHIFT TO EAST-NORTHEAST TUESDAY
AFTERNOON THROUGH WEDNESDAY.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY NIGHT/...HIGH CONFIDENCE.
SCA REMAINS POSTED ON NANTUCKET SOUND FOR LINGERING 25KT GUSTS
THROUGH LATE AFTERNOON...AND ON OUTER WATERS THROUGH MIDNIGHT
BEFORE WINDS AND SEAS SUBSIDE.
BAND OF SHOWERS DROPS S ACROSS WATERS THROUGH THIS EVENING...
MAINLY ON E MA WATERS. PATCHY FOG POSSIBLE OVERNIGHT.
WINDS AND SEAS BELOW SCA SUN WITH SEA BREEZES DEVELOPING BY
AFTERNOON. MAY SEE A FEW STRONG STORMS SUN AFTERNOON ON NEAR SHORE
WATERS WHICH WOULD BE CAPABLE OF PRODUCING 35KT GUSTS AND SMALL
HAIL...BUT STORMS SHOULD BE FOCUSED FARTHER INLAND NEAR SEA BREEZE
FRONT.
LIGHT WINDS AND CALM SEAS SUN NIGHT.
OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.
MONDAY...WEST TO SOUTHWEST WINDS WILL GUST INTO THE LOW 20S...BUT
SHOULD REMAIN BELOW 25 KNOTS. THESE WINDS WILL DRIVE SEAS TO 5-6
FEET ON THE EXPOSED WATERS LATE MONDAY AND MONDAY NIGHT. A SMALL
CRAFT ADVISORY MAY BE NEEDED ON THESE WATERS.
TUESDAY...A COLD FRONT WILL MOVE ACROSS THE WATERS DURING THE
MORNING AND EARLY AFTERNOON. THIS WILL BRING SCATTERED SHOWERS/TSTMS
AS WELL AS A SHARP WIND SHIFT...WEST WINDS IN THE MORNING AND EAST-
NORTHEAST WINDS IN THE AFTERNOON. WIND SPEEDS WILL DIMINISH DURING
THE AFTERNOON AND SEAS WILL SUBSIDE.
WEDNESDAY-THURSDAY...NORTHEAST WINDS GUSTING TO 20 KNOTS...SEAS
BELOW 5 FEET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ232.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ254>256.
&&
$$
SYNOPSIS...WTB/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...WTB/HR
AVIATION...WTB/JWD/HR
MARINE...WTB/JWD/HR
AREA FORECAST DISCUSSION
NWS TAUNTON MA
123 PM EDT SAT MAY 24 2014
.SYNOPSIS...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BECOME FOCUSED OVER
THE INTERIOR THIS AFTERNOON...THEN SHOULD AFFECT MORE OF SOUTHERN
NEW ENGLAND SUNDAY. SUMMER LIKE WARMTH ON MEMORIAL DAY WILL BE
SHORT LIVED AS A STRONG BACK DOOR COLD FRONT MOVES THROUGH THE
REGION ON TUESDAY...BRINGING COOLER TEMPS ALONG WITH SCATTERED
SHOWERS/THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...
HRRR CONTINUES TO DO BEST JOB WITH RESPECT TO RADAR TRENDS...
SHOWING W-E LINE OF CONVECTION DROPPING S FROM NORTHERN NEW
ENGLAND WHICH SHOULD REACH DOWN TO MASS PIKE CORRIDOR LATER THIS
AFTERNOON OR THIS EVENING. MODEL IS ALSO DOING WELL WITH N-S BAND
OF CONVECTION OVER E NY WHICH MAY TRIGGER ADDITIONAL SCATTERED
ACTIVITY IN WESTERN NEW ENGLAND.
INSTABILITY CERTAINLY LOOKS MEAGER WITH SB CAPES ON ORDER OF 500
J/KG OR SO AND LARGER SCALE LIFT IS RATHER WEAK...BUT COLD
TEMPERATURES ALOFT /-20C AT 500 MB/ COMBINED WITH DECENT MID LEVEL
LAPSE RATES HAS HELPED ACTIVITY DEVELOP. STRONGER CELLS COULD
SUPPORT SMALL HAIL WITH LOW FREEZING LEVELS.
CLOSER TO COAST...13KM RAP WAS CORRECT IN SHOWING CLEARING OVER
CAPE COD AND ISLANDS EARLY THIS AFTERNOON. AT LEAST SOME PARTIAL
CLEARING WILL WORK INTO SE MA BEFORE CLOUDS ARRIVE FROM NW LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
** FEW STRONG THUNDERSTORMS WITH GUSTY WINDS AND SMALL HAIL
POSSIBLE ON SUNDAY ***
TONIGHT...
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS FAR WESTERN NEW
ENGLAND WIND DOWN BY LATE EVENING. OTHERWISE...MAINLY DRY FOR THE
REST OF THE NIGHT BESIDES A SPOT SHOWER OR TWO. LOW TEMPS WILL
MAINLY BE IN THE UPPER 40S AND LOWER 50S.
SUNDAY...
INTERESTING SETUP ACROSS SOUTHERN NEW ENGLAND AS THE NEXT SHORTWAVE
DIVES DOWN IN NORTHWEST FLOW ALOFT. THIS WILL COMBINED WITH STEEP
MID LEVEL LAPSE RATES ON THE ORDER OF 6.5 TO 7.0 C/KM...500 TO 1000
J/KG OF SURFACE BASED CAPE AND 30 TO 35 KNOTS OF 0 TO 6 KM SHEAR.
IN ADDITION...A SEA BREEZE FRONT MAY ACT AS A FOCUS FOR CONVECTION
ACROSS CENTRAL/EASTERN MA AND RHODE ISLAND.
OVERALL...THINK WILL SEE SCATTERED SHOWERS/THUNDERSTORMS DEVELOP
LATE SUNDAY MORNING/AFTERNOON WITH THE SHORTWAVE. GIVEN ABOVE
PARAMETERS...FEEL A FEW OF THE STRONGER STORMS MAY CONTAIN SMALL
HAIL/GUSTY WINDS AND HAVE ADDED ENHANCED WORDING TO THE FORECAST.
IN ADDITION...ALTHOUGH CAPE VALUES ARE LOWER THAN WE LIKE TO SEE FOR
SEVERE WEATHER...A BIT CONCERNED ABOUT 500 MB TEMPS BELOW -20C.
SOMETIMES THOSE COLD POOLS ALOFT CAN OVER PERFORM...SO AN ISOLATED
SEVERE THUNDERSTORM OR TWO CAN NOT BE RULED OUT ESPECIALLY NEAR THE
SEA BREEZE FRONT. FINALLY...THE THREAT WILL EXIST FOR LOCALLY HEAVY
RAINFALL/POOR DRAINAGE STREET FLOODING IF STORMS CAN TRAIN ALONG SEA
BREEZE BOUNDARY.
HIGH TEMPS SHOULD MAINLY BE IN THE 70S...EXCEPT 60S ON THE IMMEDIATE
COAST WITH SEA BREEZES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* WARM DAY MON FOLLOWED BY STRONG BACKDOOR COLD FRONT ON TUE
* ANY TSTMS LATE MON TO TUE PERIOD COULD HAVE STRONG WIND GUSTS
OVERVIEW...OVERALL UPPER AIR PATTERN AMPLIFIES DURING THIS TIME
PERIOD WITH CLOSED LOW SOMEWHERE S OR SE OF NEW ENGLAND BY END OF
WEEK...MORE REMINISCENT OF EARLY THAN LATE SPRING. HIGH CONFIDENCE
OF A STRONG BACKDOOR COLD FRONT MOVING THROUGH ON TUE BUT
UNCERTAIN WITH RESPECT TO TIMING. NW FLOW ALOFT REST OF WEEK.
ALTHOUGH LOOKS MAINLY DRY AFTER TUE...RISK OF SHORT WAVE ENERGY
EMBEDDED IN NW FLOW TRIGGERING ISOLATED AFTERNOON SHOWERS/TSTMS.
ONSHORE FLOW SHOULD KEEP EASTERN SECTIONS IN PARTICULAR ON COOL
SIDE. H50 TEMPS TURN COLDER LATE IN THE WEEK AND SET THE STAGE FOR
POSSIBLE AFTERNOON CONVECTION.
DETAILS...
MON...W OR EVEN WNW OFFSHORE AND DOWNSLOPING SURFACE FLOW AND H85 TEMPS
INCREASING TO AROUND 13C IN THE AFTERNOON SHOULD RESULT IN A VERY
WARM DAY WITH TEMPS PROBABLY REACHING MID TO UPPER 80S ACROSS MOST
OF AREA. EVEN THE CAPE SHOULD BE WARM WITH THIS FLOW. OPTED TO GO
SEVERAL DEGREES ABOVE MODEL CONSENSUS. BELIEVE SOUTHERN NEW
ENGLAND SHOULD REMAIN DRY THROUGH THE DAY...EXCEPT FOR A LOW
CHANCE OF TSTMS ALONG AND NE OF A MHT-BVY LINE LATE IN THE DAY AS
AIR MASS DESTABILIZES AHEAD OF BACKDOOR COLD FRONT ACROSS MAINE.
WIND SHEAR INCREASES AND ANY TSTMS THAT DO DEVELOP WOULD HAVE
POTENTIAL OF PRODUCING STRONG WIND GUSTS.
MON NIGHT...SOME RISK OF CONVECTION ESPECIALLY ALONG AND NE OF A
ORE-ORH-PYM-CQX LINE. ALTHOUGH NOT A DIURNALLY FAVORABLE TIME FOR
SURFACE BASED CONVECTION...STRONG WIND SHEAR AND MODERATELY
UNSTABLE MID LEVEL LAPSE RATES COULD YIELD ISOLATED STRONG/SEVERE
TSTMS. OTHERWISE...SHOULD BE A RELATIVELY WARM NIGHT WITH TEMPS
OVER MUCH OF THE REGION NOT DROPPING BELOW THE 60S.
TUE...THIS COULD BE A VERY INTERESTING DAY WITH DRAMATIC TEMP
CHANGES SPATIALLY AND TEMPORALLY...DEPENDENT UPON TIMING OF A
BACKDOOR COLD FRONT. FOR NOW...THINKING TEMPS WILL QUICKLY RISE TO
AT LEAST MID 70S E MA AND RI BEFORE CRASHING DURING THE AFTERNOON
WITH BACKDOOR COLD FRONT PASSAGE. MAY SEE DRAMATIC TEMP DROP IN
EASTERN MA AND RI FROM MID/UPPER 70S TO MID/UPPER 50S IN JUST AN
HOUR OR TWO. TEMPS MAY REACH MID/UPPER 80S CT VALLEY OF NH...MA
AND CT BEFORE DROPPING LATE IN THE DAY...WARMEST GREATER HARTFORD
AREA. LOW CONFIDENCE ON SHOWER/TSTM POTENTIAL. INSTABILITY
PARAMETERS SUGGEST RISK OF SHOWERS/TSTMS...BUT LOCATION AND
STRENGTH DEPENDENT UPON COLD FRONT TIMING. TOTAL TOTALS NEAR
50...K INDEX NEAR OR SLIGHTLY ABOVE 30...SHOWALTERS NEAR 0 AND MID
LEVEL LAPSE RATES AROUND 6.5 C/KM ALL POINT TO CHANCE TSTMS AND
POTENTIALLY RISK OF STRONG/SVR TSTMS GIVEN 0-6 KM VERTICAL SHEAR
OF 40-45 KT. WILL INDICATE CHANCE TSTMS GIVEN MODEL
SIGNAL...ALTHOUGH IT IS SOMEWHAT ATYPICAL TO HAVE A LOT OF
CONVECTION AHEAD OF A BACKDOOR FRONT IN EASTERN MA.
TUE NIGHT-THU NIGHT...ONSHORE FLOW SHOULD CAP MAX TEMPS NEAR THE
COAST GENERALLY IN MID 60S WITH LOW/MID 70S CT VALLEY REGION.
LOOKS TO BE MAINLY DRY THROUGH THIS PERIOD WITH ONSHORE FLOW AND
NO APPARENT FORCING.
FRI...SOME SUGGESTION OF COOLING 500 MB TEMPS WHICH COULD LEAD TO CHANCE
OF AFTERNOON SHOWERS/TSTMS. TEMPS LIKELY REMAINING NEAR TO
SOMEWHAT BELOW NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH SUNDAY NIGHT...MODERATE CONFIDENCE.
BAND OF SHOWERS/ISOLD TSTMS WITH MVFR CIGS/VSBYS WILL DROP S
ACROSS NEW ENGLAND THROUGH THIS EVENING...PROBABLY REACHING AS FAR
AS KBAF-KORH-KBOS BEFORE WEAKENING. ADDITIONAL SCT SHOWERS/ISOLD
TSTMS MAY DEVELOP NEAR BERKSHIRES THROUGH SUNSET. OTHERWISE VFR
CIGS AOA 050 THROUGH TONIGHT...EXCEPT AROUND CAPE COD AND ISLANDS
WHERE PERIOD OF MVFR CIGS SHOULD OCCUR TOWARD DAYBREAK.
ANOTHER ROUND OF SCT SHOWERS/TSTMS EXPECTED SUN WITH MVFR/IFR
CONDITIONS...PRIMARILY ACROSS INTERIOR. ACTIVITY MAY BECOME
FOCUSED ALONG SEA BREEZE FRONT AROUND MIDDAY WHICH SHOULD EXTEND
NEAR KASH-KBED-KTAN CORRIDOR. SOME STORMS COULD PRODUCE SMALL HAIL
AND BRIEF WIND GUSTS TO 35KT. ACTIVITY SUBSIDES SUN EVENING WITH
VFR CONDITIONS EXPECTED.
KBOS TAF...MODERATE CONFIDENCE. MVFR POSSIBLE 21Z-23Z AS BAND OF
SHOWERS/ISOLD TSTMS DROPS S. HIGH CONFIDENCE IN SEA BREEZE SUN.
KBDL TAF...MODERATE CONFIDENCE. LOW PROBABILITY OF ISOLD TSTM LATE
THIS AFTERNOON BUT ACTIVITY SHOULD REMAIN FARTHER W.
OUTLOOK...MONDAY THROUGH TUESDAY...
MONDAY THROUGH TUESDAY....MODERATE CONFIDENCE OF PREVAILING VFR
CONDITIONS WITH AREAS OF MVFR CIGS/VSBYS IN SCT SHOWERS/TSTMS.
TUESDAY NIGHT...LOW CONFIDENCE OF MVFR-IFR CIGS BEHIND COLD FRONT.
WEDNESDAY...LOW CONFIDENCE OF MAINLY VFR WEST AND MVFR CIGS EAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...HIGH CONFIDENCE.
THROUGH THIS AFTERNOON...
NANTUCKET SOUND ADDED BACK TO SCA FOR 25KT GUSTS THROUGH LATE
AFTERNOON...MAINLY NEAR NANTUCKET. CLEARING HAS ALLOWED FOR DEEPER
MIXING AND WAS SUPPORTING 25-30KT GUSTS AT NANTUCKET AIRPORT.
GUSTS SHOULD SLOWLY SUBSIDE THROUGH AFTERNOON. ALSO EXTENDED SCA
FOR OUTER WATERS UNTIL MIDNIGHT...WHERE WINDS AND SEAS WILL TAKE
AWHILE LONGER TO SUBSIDE AS LOW PRESSURE HEADS FARTHER OUT TO SEA.
TONIGHT AND SUNDAY...
WINDS AND SEAS DIMINISH BELOW SCA THRESHOLDS EARLY THIS EVENING
ACROSS THE SOUTHERN ATLANTIC WATERS AS PRESSURE GRADIENT WEAKENS.
OTHERWISE...WINDS/SEAS WILL BE BELOW SCA CRITERIA TONIGHT AND
SUNDAY. WE MAY HAVE TO WATCH FOR A FEW STRONG THUNDERSTORMS ON
SUNDAY ACROSS THE NEAR SHORE WATERS...WITH GUSTY WINDS AND SMALL
HAIL.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
MODERATE CONFIDENCE OVERALL.
EXPECT WINDS AND SEAS TO REMAIN BELOW SCA CRITERIA THROUGH MON
NIGHT. HOWEVER...LOCALLY STRONG WIND GUSTS POSSIBLE IN VICINITY
OF ANY TSTMS LATE MON/MON NIGHT OVER COASTAL WATERS...MAINLY NORTH
OF PYM AND PVC. MORE SCT TSTMS WITH BRIEF STRONG WIND GUSTS
POSSIBLE OVER THE WATERS ON TUE. LOW CONFIDENCE OF A POSSIBLE
PERIOD OF NE WIND GUSTS TO 25 KT AND 3 TO 5 FT WIND WAVES BRIEFLY
BEHIND BACKDOOR COLD FRONT TUE AFTERNOON. ANTICIPATE WINDS AND
SEAS TO BE BELOW OR DROPPING BELOW SCA CRITERIA ON WEDNESDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ232.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ254>256.
&&
$$
SYNOPSIS...FRANK/THOMPSON
NEAR TERM...JWD
SHORT TERM...FRANK
LONG TERM...THOMPSON
AVIATION...JWD
MARINE...JWD
AREA FORECAST DISCUSSION
NWS TAUNTON MA
104 PM EDT SAT MAY 24 2014
.SYNOPSIS...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BECOME FOCUSED OVER
THE INTERIOR THIS AFTERNOON...THEN SHOULD AFFECT MORE OF SOUTHERN
NEW ENGLAND SUNDAY. SUMMER LIKE WARMTH ON MEMORIAL DAY WILL BE
SHORT LIVED AS A STRONG BACK DOOR COLD FRONT MOVES THROUGH THE
REGION ON TUESDAY...BRINGING COOLER TEMPS ALONG WITH SCATTERED
SHOWERS/THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...
HRRR CONTINUES TO DO BEST JOB WITH RESPECT TO RADAR TRENDS...
SHOWING W-E LINE OF CONVECTION DROPPING S FROM NORTHERN NEW
ENGLAND WHICH SHOULD REACH DOWN TO MASS PIKE CORRIDOR LATER THIS
AFTERNOON OR THIS EVENING. MODEL IS ALSO DOING WELL WITH N-S BAND
OF CONVECTION OVER E NY WHICH MAY TRIGGER ADDITIONAL SCATTERED
ACTIVITY IN WESTERN NEW ENGLAND.
INSTABILITY CERTAINLY LOOKS MEAGER WITH SB CAPES ON ORDER OF 500
J/KG OR SO AND LARGER SCALE LIFT IS RATHER WEAK...BUT COLD
TEMPERATURES ALOFT /-20C AT 500 MB/ COMBINED WITH DECENT MID LEVEL
LAPSE RATES HAS HELPED ACTIVITY DEVELOP. STRONGER CELLS COULD
SUPPORT SMALL HAIL WITH LOW FREEZING LEVELS.
CLOSER TO COAST...13KM RAP WAS CORRECT IN SHOWING CLEARING OVER
CAPE COD AND ISLANDS EARLY THIS AFTERNOON. AT LEAST SOME PARTIAL
CLEARING WILL WORK INTO SE MA BEFORE CLOUDS ARRIVE FROM NW LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
** FEW STRONG THUNDERSTORMS WITH GUSTY WINDS AND SMALL HAIL
POSSIBLE ON SUNDAY ***
TONIGHT...
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS FAR WESTERN NEW
ENGLAND WIND DOWN BY LATE EVENING. OTHERWISE...MAINLY DRY FOR THE
REST OF THE NIGHT BESIDES A SPOT SHOWER OR TWO. LOW TEMPS WILL
MAINLY BE IN THE UPPER 40S AND LOWER 50S.
SUNDAY...
INTERESTING SETUP ACROSS SOUTHERN NEW ENGLAND AS THE NEXT SHORTWAVE
DIVES DOWN IN NORTHWEST FLOW ALOFT. THIS WILL COMBINED WITH STEEP
MID LEVEL LAPSE RATES ON THE ORDER OF 6.5 TO 7.0 C/KM...500 TO 1000
J/KG OF SURFACE BASED CAPE AND 30 TO 35 KNOTS OF 0 TO 6 KM SHEAR.
IN ADDITION...A SEA BREEZE FRONT MAY ACT AS A FOCUS FOR CONVECTION
ACROSS CENTRAL/EASTERN MA AND RHODE ISLAND.
OVERALL...THINK WILL SEE SCATTERED SHOWERS/THUNDERSTORMS DEVELOP
LATE SUNDAY MORNING/AFTERNOON WITH THE SHORTWAVE. GIVEN ABOVE
PARAMETERS...FEEL A FEW OF THE STRONGER STORMS MAY CONTAIN SMALL
HAIL/GUSTY WINDS AND HAVE ADDED ENHANCED WORDING TO THE FORECAST.
IN ADDITION...ALTHOUGH CAPE VALUES ARE LOWER THAN WE LIKE TO SEE FOR
SEVERE WEATHER...A BIT CONCERNED ABOUT 500 MB TEMPS BELOW -20C.
SOMETIMES THOSE COLD POOLS ALOFT CAN OVER PERFORM...SO AN ISOLATED
SEVERE THUNDERSTORM OR TWO CAN NOT BE RULED OUT ESPECIALLY NEAR THE
SEA BREEZE FRONT. FINALLY...THE THREAT WILL EXIST FOR LOCALLY HEAVY
RAINFALL/POOR DRAINAGE STREET FLOODING IF STORMS CAN TRAIN ALONG SEA
BREEZE BOUNDARY.
HIGH TEMPS SHOULD MAINLY BE IN THE 70S...EXCEPT 60S ON THE IMMEDIATE
COAST WITH SEA BREEZES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* WARM DAY MON FOLLOWED BY STRONG BACKDOOR COLD FRONT ON TUE
* ANY TSTMS LATE MON TO TUE PERIOD COULD HAVE STRONG WIND GUSTS
OVERVIEW...OVERALL UPPER AIR PATTERN AMPLIFIES DURING THIS TIME
PERIOD WITH CLOSED LOW SOMEWHERE S OR SE OF NEW ENGLAND BY END OF
WEEK...MORE REMINISCENT OF EARLY THAN LATE SPRING. HIGH CONFIDENCE
OF A STRONG BACKDOOR COLD FRONT MOVING THROUGH ON TUE BUT
UNCERTAIN WITH RESPECT TO TIMING. NW FLOW ALOFT REST OF WEEK.
ALTHOUGH LOOKS MAINLY DRY AFTER TUE...RISK OF SHORT WAVE ENERGY
EMBEDDED IN NW FLOW TRIGGERING ISOLATED AFTERNOON SHOWERS/TSTMS.
ONSHORE FLOW SHOULD KEEP EASTERN SECTIONS IN PARTICULAR ON COOL
SIDE. H50 TEMPS TURN COLDER LATE IN THE WEEK AND SET THE STAGE FOR
POSSIBLE AFTERNOON CONVECTION.
DETAILS...
MON...W OR EVEN WNW OFFSHORE AND DOWNSLOPING SURFACE FLOW AND H85 TEMPS
INCREASING TO AROUND 13C IN THE AFTERNOON SHOULD RESULT IN A VERY
WARM DAY WITH TEMPS PROBABLY REACHING MID TO UPPER 80S ACROSS MOST
OF AREA. EVEN THE CAPE SHOULD BE WARM WITH THIS FLOW. OPTED TO GO
SEVERAL DEGREES ABOVE MODEL CONSENSUS. BELIEVE SOUTHERN NEW
ENGLAND SHOULD REMAIN DRY THROUGH THE DAY...EXCEPT FOR A LOW
CHANCE OF TSTMS ALONG AND NE OF A MHT-BVY LINE LATE IN THE DAY AS
AIR MASS DESTABILIZES AHEAD OF BACKDOOR COLD FRONT ACROSS MAINE.
WIND SHEAR INCREASES AND ANY TSTMS THAT DO DEVELOP WOULD HAVE
POTENTIAL OF PRODUCING STRONG WIND GUSTS.
MON NIGHT...SOME RISK OF CONVECTION ESPECIALLY ALONG AND NE OF A
ORE-ORH-PYM-CQX LINE. ALTHOUGH NOT A DIURNALLY FAVORABLE TIME FOR
SURFACE BASED CONVECTION...STRONG WIND SHEAR AND MODERATELY
UNSTABLE MID LEVEL LAPSE RATES COULD YIELD ISOLATED STRONG/SEVERE
TSTMS. OTHERWISE...SHOULD BE A RELATIVELY WARM NIGHT WITH TEMPS
OVER MUCH OF THE REGION NOT DROPPING BELOW THE 60S.
TUE...THIS COULD BE A VERY INTERESTING DAY WITH DRAMATIC TEMP
CHANGES SPATIALLY AND TEMPORALLY...DEPENDENT UPON TIMING OF A
BACKDOOR COLD FRONT. FOR NOW...THINKING TEMPS WILL QUICKLY RISE TO
AT LEAST MID 70S E MA AND RI BEFORE CRASHING DURING THE AFTERNOON
WITH BACKDOOR COLD FRONT PASSAGE. MAY SEE DRAMATIC TEMP DROP IN
EASTERN MA AND RI FROM MID/UPPER 70S TO MID/UPPER 50S IN JUST AN
HOUR OR TWO. TEMPS MAY REACH MID/UPPER 80S CT VALLEY OF NH...MA
AND CT BEFORE DROPPING LATE IN THE DAY...WARMEST GREATER HARTFORD
AREA. LOW CONFIDENCE ON SHOWER/TSTM POTENTIAL. INSTABILITY
PARAMETERS SUGGEST RISK OF SHOWERS/TSTMS...BUT LOCATION AND
STRENGTH DEPENDENT UPON COLD FRONT TIMING. TOTAL TOTALS NEAR
50...K INDEX NEAR OR SLIGHTLY ABOVE 30...SHOWALTERS NEAR 0 AND MID
LEVEL LAPSE RATES AROUND 6.5 C/KM ALL POINT TO CHANCE TSTMS AND
POTENTIALLY RISK OF STRONG/SVR TSTMS GIVEN 0-6 KM VERTICAL SHEAR
OF 40-45 KT. WILL INDICATE CHANCE TSTMS GIVEN MODEL
SIGNAL...ALTHOUGH IT IS SOMEWHAT ATYPICAL TO HAVE A LOT OF
CONVECTION AHEAD OF A BACKDOOR FRONT IN EASTERN MA.
TUE NIGHT-THU NIGHT...ONSHORE FLOW SHOULD CAP MAX TEMPS NEAR THE
COAST GENERALLY IN MID 60S WITH LOW/MID 70S CT VALLEY REGION.
LOOKS TO BE MAINLY DRY THROUGH THIS PERIOD WITH ONSHORE FLOW AND
NO APPARENT FORCING.
FRI...SOME SUGGESTION OF COOLING 500 MB TEMPS WHICH COULD LEAD TO CHANCE
OF AFTERNOON SHOWERS/TSTMS. TEMPS LIKELY REMAINING NEAR TO
SOMEWHAT BELOW NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH SUNDAY NIGHT...MODERATE CONFIDENCE.
BAND OF SHOWERS/ISOLD TSTMS WITH MVFR CIGS/VSBYS WILL DROP S
ACROSS NEW ENGLAND THROUGH THIS EVENING...PROBABLY REACHING AS FAR
AS KBAF-KORH-KBOS BEFORE WEAKENING. ADDITIONAL SCT SHOWERS/ISOLD
TSTMS MAY DEVELOP NEAR BERKSHIRES THROUGH SUNSET. OTHERWISE VFR
CIGS AOA 050 THROUGH TONIGHT...EXCEPT AROUND CAPE COD AND ISLANDS
WHERE PERIOD OF MVFR CIGS SHOULD OCCUR TOWARD DAYBREAK.
ANOTHER ROUND OF SCT SHOWERS/TSTMS EXPECTED SUN WITH MVFR/IFR
CONDITIONS...PRIMARILY ACROSS INTERIOR. ACTIVITY MAY BECOME
FOCUSED ALONG SEA BREEZE FRONT AROUND MIDDAY WHICH SHOULD EXTEND
NEAR KASH-KBED-KTAN CORRIDOR. SOME STORMS COULD PRODUCE SMALL HAIL
AND BRIEF WIND GUSTS TO 35KT. ACTIVITY SUBSIDES SUN EVENING WITH
VFR CONDITIONS EXPECTED.
KBOS TAF...MODERATE CONFIDENCE. MVFR POSSIBLE 21Z-23Z AS BAND OF
SHOWERS/ISOLD TSTMS DROPS S. HIGH CONFIDENCE IN SEA BREEZE SUN.
KBDL TAF...MODERATE CONFIDENCE. LOW PROBABILITY OF ISOLD TSTM LATE
THIS AFTERNOON BUT ACTIVITY SHOULD REMAIN FARTHER W.
OUTLOOK...MONDAY THROUGH TUESDAY...
MONDAY THROUGH TUESDAY....MODERATE CONFIDENCE OF PREVAILING VFR
CONDITIONS WITH AREAS OF MVFR CIGS/VSBYS IN SCT SHOWERS/TSTMS.
TUESDAY NIGHT...LOW CONFIDENCE OF MVFR-IFR CIGS BEHIND COLD FRONT.
WEDNESDAY...LOW CONFIDENCE OF MAINLY VFR WEST AND MVFR CIGS EAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY AFTERNOON/...HIGH CONFIDENCE.
THROUGH THIS AFTERNOON...
NE WINDS GRADUALLY DIMINISH AS LOW PRES PASSES WELL SE OF WATERS.
DROPPED SCA ON NANTUCKET SOUND BUT WILL MAINTAIN IT FARTHER
OFFSHORE FOR COMBINATION OF 25KT WINDS AND 5 FT SEAS.
TONIGHT AND SUNDAY...
WINDS AND SEAS DIMINISH BELOW SCA THRESHOLDS EARLY THIS EVENING
ACROSS THE SOUTHERN ATLANTIC WATERS AS PRESSURE GRADIENT WEAKENS.
OTHERWISE...WINDS/SEAS WILL BE BELOW SCA CRITERIA TONIGHT AND
SUNDAY. WE MAY HAVE TO WATCH FOR A FEW STRONG THUNDERSTORMS ON
SUNDAY ACROSS THE NEAR SHORE WATERS...WITH GUSTY WINDS AND SMALL
HAIL.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
MODERATE CONFIDENCE OVERALL.
EXPECT WINDS AND SEAS TO REMAIN BELOW SCA CRITERIA THROUGH MON
NIGHT. HOWEVER...LOCALLY STRONG WIND GUSTS POSSIBLE IN VICINITY
OF ANY TSTMS LATE MON/MON NIGHT OVER COASTAL WATERS...MAINLY NORTH
OF PYM AND PVC. MORE SCT TSTMS WITH BRIEF STRONG WIND GUSTS
POSSIBLE OVER THE WATERS ON TUE. LOW CONFIDENCE OF A POSSIBLE
PERIOD OF NE WIND GUSTS TO 25 KT AND 3 TO 5 FT WIND WAVES BRIEFLY
BEHIND BACKDOOR COLD FRONT TUE AFTERNOON. ANTICIPATE WINDS AND
SEAS TO BE BELOW OR DROPPING BELOW SCA CRITERIA ON WEDNESDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
ANZ254>256.
&&
$$
SYNOPSIS...FRANK/THOMPSON
NEAR TERM...JWD
SHORT TERM...FRANK
LONG TERM...THOMPSON
AVIATION...JWD
MARINE...JWD
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1241 PM CDT Sat May 24 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 327 AM CDT SAT MAY 24 2014
Forecast for the next 24 hours remains mostly unchanged with a similar
environment seen for the past few days. Morning analysis shows the
upper trough responsible for this unsettled pattern rotating over
northern AZ with a broad upper ridge over the northern plains. A
series of embedded weak troughs were noted over the central plains.
One in particular across northern OK into southeast KS continues to
impact our CWA through the morning hours. A warm moist plume was
spreading northeast into southern and eastern Kansas as dewpoints
increase into the lower and middle 60s through the afternoon.
The increasing LLJ with the additional lift from the upper wave and
saturated atmospheric profile across northeast Kansas support the
current convection across southern portions of the area to continue,
if not increase in coverage through the morning and afternoon.
Activity is not expected to be severe through the day due to CAPE
values staying low near 1000 J/KG. Shear values, especially
directionally, increase a bit higher than yesterday in the 20 to 25
kt range with perhaps the stronger updrafts producing small hail and
gusty winds near 40 mph. The more pressing concern with convection
today will be the heavy rain. PWAT values increase to 1.6 inches
with mean h5 flow very weak suggesting slow-moving convection
generating outflow that triggers additional convection. The latest
NAM, GFS, ECMWF, and HRRR are similar in developing a heavier band
of rain impacting much of the area from now through at least 1 PM.
Areas near and south of Interstate 70 corridor stand the better
chances for flash flooding. A generous rainfall amount from 0.20 to
0.75 inches is likely with locally higher amounts from 1 to 2
inches with training convection. Likely precip chances decline to a
chance by this evening as guidance varies on if and where precip
redevelops from another weak upper wave.
Latest guidance was trending slightly cooler on temperatures today
due to extensive cloud cover and precip in the area. Lowered highs a
few degrees to the mid 70s but could still be too warm dependent on
precip coverage through the day. Lows this evening were unchanged in
the middle 60s.
.LONG TERM...(Sunday through Friday)
Issued at 327 AM CDT SAT MAY 24 2014
For Sunday through Tuesday, the forecast area is likely to remain
under the influence of the closed low to the west. Models are in
reasonably good agreement with the cut off low`s slow progression
east, and they maintain a conditionally unstable atmosphere with
decent moisture available and no real inhibition to convection.
With the occasional wave lifting out of the low providing some
forcing, scattered to numerous showers and thunderstorm should
develop. The forecast continues with POPs of 40 to 50 percent
during the daytime, mainly because there is no clear surface
feature to focus convection and pin point one location more likely
to receive precip over another. Deep layer sheer remains
unimpressive so organized severe weather looks unlikely. Really
with PWs near 1.5 inches, localized flash flooding remains the
main concern with the thunderstorm activity. Temps should not
change much from day to day since there is no real change in
airmass, so the temp forecast is generally a persistence forecast
of lows in the 60s and highs around 80.
By Wednesday, models are beginning to converge on an idea of the
closed upper low moving southeast gradually. Because of this the
forecast begins a trend down in POPs, but not completely doing
away with them. The GFS still suggests the atmosphere will be
conditionally unstable through the end of the week and that all is
needed might be some weak lift or weak forcing to generate precip.
Therefore some slight chances have been retained for Thursday and
Friday. Uncertainty is a bit higher for the end of the week since
the synoptic flow remains rather weak over the central plains.
This allows the GFS to bring a weak backdoor front into the area
while the ECMWF favors mid level ridging. Temps should see a
slight warming trend through the end of the work week due to
rising mid level heights and increases in insolation. However
strong warm air advection does not look to affect the area so
highs are forecast to warm into the mid 80s by Friday. Lows should
remain in the 60s.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1236 PM CDT SAT MAY 24 2014
Ceilings should increase to VFR at terminal MHK by 20Z SAT.
Thunderstorm may redevelop this afternoon near the terminals but
should end after 2Z SUN. May see scattered showers through
the night and into Sunday morning. Expect MVFR ceilings at times
late tonight and through Sunday morning.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...GARGAN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1228 PM CDT Sat May 24 2014
...Updated aviation section...
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SAT MAY 24 2014
As the atmosphere destabilizes this afternoon the best instability
will be on the order of a couple of thousand J/kg located across
NW Kansas through central Kansas with less emphasis on the farther
western counties. Bulk shear values will be quite weak however. The
CAPE values will be owing largely to moisture as widespread low
level stratus will need to slowly erode this morning. With adequate
lift, a few rounds of shower and scattered thunderstorms will occur
again today as on Friday. The convective allowing models are not in
good agreement on the timing of convection as the 6Z runs are
indicating strongly forced convection between 00 and 06 UTC this
evening. The NAM solution expands what appeared to be the
aforementioned convection across the panhandles northward into
western Kansas later this morning associated with a isentropic lift
pattern. Initially we`ve maintained little if any POPS until around
18 z before ramping up chances through he afternoon and evening.
The current HRRR is not a tremendous help at this time as the
precipitation associated with the panhandles storm trends to
diminishing near Elkhart around 16 UTC. Beyond convective chances,
the highs will not be appreciably warmer than yesterday given the
expansive cloud cover. Another night of mild temperatures is
expected across central Kansas where temperature will not fall below
60 degrees, with stratus and potentially developing fog as
well.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 1212 PM CDT SAT MAY 24 2014
A blocky flow regime will continue in the central United States most
of next week as the closed upper level cyclone in Arizona wallows
slowly east into the Oklahoma Panhandle Monday and into northern
Oklahoma by Tuesday evening. Upper level ridging will build from
Mexico into the Central Plains north of the upper level cyclone, and
the remnants of the cyclone should propagate south to the Texas Gulf
Coast next weekend on the southern periphery of the upper level
ridge extending from Mexico to the Upper Midwest. The net result
will be a return to warm and quiet weather in western Kansas from
Tuesday through Friday.
A weakening Madden Julian Oscillation may propagate across Africa
into the Indian Ocean by the end of May, but any coherent signal
will be weak and will have little influence on the mid latitude flow
regime. Global relative angular momentum has been above climatology
since mid May, but mountain torque has trended toward negative
territory in recent days. The atmosphere appears to be best
represented by Phase 8 of the Weickmann-Berry Phase Space diagram
and may trend toward Phase 1 by the end of next week given the
probable continued negative tendency in global relative angular
momentum. Phase 8 and 1 both favor cyclonic flow in the western
United States, so the concept of maintaining a mean long wave trough
near 120W with a ridge in the eastern Pacific and a trend toward
ridging from Mexico into the Southern Plains seems very reasonable.
If some sort of coherent cluster of enhanced tropical thunderstorms
does move across the Indian Ocean the first part of June, upper
level ridging may be enhanced in the western United States, and
another surge of cool air may spread into the central part of the
country the first week of June.
The extensive rainfall that has occurred in the Texas Panhandle,
eastern New Mexico and western Oklahoma in recent days will favor at
least some greening of vegetation and will have an effect on the
weather in western Kansas in June. Increased evapotranspiration will
support higher dewpoints in western Kansas at least for a while. The
pool of warm ocean temperatures in the mid latitudes in the North
Pacific has continued to shift eastward with time, and ocean
temperatures are above climatology along the west coast of Canada.
This is different from what was observed in 2012 and 2013 and may
favor northwest flow aloft across the Central Plains and increased
incidence of nocturnal thunderstorm clusters propagating from
northeastern Colorado across western Kansas this summer. Guidance
still suggests that rainfall in June will be above climatology,
especially in northern Kansas.
In the more immediate future, the numerical models are in
surprisingly good agreement with propagation of the closed upper
level cyclone as it approaches the Oklahoma Panhandle Monday and
moves into northern Oklahoma Tuesday. The 12Z GFS agrees well with
the 00Z ECMWF and largely was used for minor grid adjustments. A
moist and marginally unstable atmosphere will continue in western
Kansas, and minor troughs rotating around the upper level cyclone
will support episodes of thunderstorms with locally heavy rainfall.
The GFS and ECMWF both move a minor upper level trough evident on
satellite imagery in central California around the upper level
cyclone into western Oklahoma Sunday night. This should support
development of a cluster of thunderstorms that will move into south
central Kansas Sunday night and weaken in central Kansas Monday
morning. Scattered thunderstorms in the vicinity of the upper level
cold pool could occur about any where in Kansas Monday afternoon and
Monday evening, although the cold pool across the southern part of
the state may be the favored area for more widespread showers and
thunderstorms. Any weak boundary near the upper level cyclone will
have to be watched for the possibility weak nonmesocyclone tornado
formation in the moist environment.
On Tuesday, the upper level cyclone still will be close enough to
south central Kansas to support diurnally modulated thunderstorm
development, but chances will decrease Wednesday and Thursday as
upper level ridging builds in eastern Colorado and western Kansas.
The GFS continues to try to bring the remnants of TS Amanda north
into Arizona Friday and into eastern Colorado by Saturday morning,
while the ECMWF carries most of the remnants of Amanda west into the
cooler waters of the Pacific. If the GFS verifies, there will be an
increased chance for thunderstorms in western Kansas Saturday;
however, confidence is far too low to get too carried away with rain
chances. Upper level ridging will build in central Canada around 1
June, and a cold front is likely to move into northern Kansas. A
warm mid level plume should spread into the High Plains next
weekend, and the potential exists for nocturnal thunderstorm
clusters along the edge of the elevated mixed layer the few days of
June.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1224 PM CDT SAT MAY 24 2014
VFR conditions will prevail across the DDC and GCK terminals this
afternoon with MVFR conditions at HYS. Winds will generally be
light and variable becoming southeast at 5 to 10 knots this
evening. There will be a slight chance of thunderstorms this
afternoon into this evening, but confidence is low on the timing.
To account for this I have placed VCTS in the TAFs.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 61 79 58 / 40 50 40 50
GCK 79 58 79 57 / 40 50 30 40
EHA 76 57 78 56 / 40 50 30 40
LBL 79 60 80 57 / 40 50 40 40
HYS 78 60 80 59 / 40 50 40 50
P28 82 63 78 62 / 40 50 40 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Gerard
SHORT TERM...Russell
LONG TERM...Ruthi
AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1217 PM CDT Sat May 24 2014
...Updated Long Term Section...
.UPDATE...
ISSUED AT 655 AM CDT SAT MAY 24 2014
Have updated the forecast to include some patchy fog over far southwest
Kansas, generally along and west of Highway 23 from Dighton to Meade.
Some locally dense fog will be possible for an hour or so before the
the fog begins to burn off with daytime heating.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SAT MAY 24 2014
As the atmosphere destabilizes this afternoon the best instability
will be on the order of a couple of thousand J/kg located across
NW Kansas through central Kansas with less emphasis on the farther
western counties. Bulk shear values will be quite weak however. The
CAPE values will be owing largely to moisture as widespread low
level stratus will need to slowly erode this morning. With adequate
lift, a few rounds of shower and scattered thunderstorms will occur
again today as on Friday. The convective allowing models are not in
good agreement on the timing of convection as the 6Z runs are
indicating strongly forced convection between 00 and 06 UTC this
evening. The NAM solution expands what appeared to be the
aforementioned convection across the panhandles northward into
western Kansas later this morning associated with a isentropic lift
pattern. Initially we`ve maintained little if any POPS until around
18 z before ramping up chances through he afternoon and evening.
The current HRRR is not a tremendous help at this time as the
precipitation associated with the panhandles storm trends to
diminishing near Elkhart around 16 UTC. Beyond convective chances,
the highs will not be appreciably warmer than yesterday given the
expansive cloud cover. Another night of mild temperatures is
expected across central Kansas where temperature will not fall below
60 degrees, with stratus and potentially developing fog as
well.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 1212 PM CDT SAT MAY 24 2014
A blocky flow regime will continue in the central United States most
of next week as the closed upper level cyclone in Arizona wallows
slowly east into the Oklahoma Panhandle Monday and into northern
Oklahoma by Tuesday evening. Upper level ridging will build from
Mexico into the Central Plains north of the upper level cyclone, and
the remnants of the cyclone should propagate south to the Texas Gulf
Coast next weekend on the southern periphery of the upper level
ridge extending from Mexico to the Upper Midwest. The net result
will be a return to warm and quiet weather in western Kansas from
Tuesday through Friday.
A weakening Madden Julian Oscillation may propagate across Africa
into the Indian Ocean by the end of May, but any coherent signal
will be weak and will have little influence on the mid latitude flow
regime. Global relative angular momentum has been above climatology
since mid May, but mountain torque has trended toward negative
territory in recent days. The atmosphere appears to be best
represented by Phase 8 of the Weickmann-Berry Phase Space diagram
and may trend toward Phase 1 by the end of next week given the
probable continued negative tendency in global relative angular
momentum. Phase 8 and 1 both favor cyclonic flow in the western
United States, so the concept of maintaining a mean long wave trough
near 120W with a ridge in the eastern Pacific and a trend toward
ridging from Mexico into the Southern Plains seems very reasonable.
If some sort of coherent cluster of enhanced tropical thunderstorms
does move across the Indian Ocean the first part of June, upper
level ridging may be enhanced in the western United States, and
another surge of cool air may spread into the central part of the
country the first week of June.
The extensive rainfall that has occurred in the Texas Panhandle,
eastern New Mexico and western Oklahoma in recent days will favor at
least some greening of vegetation and will have an effect on the
weather in western Kansas in June. Increased evapotranspiration will
support higher dewpoints in western Kansas at least for a while. The
pool of warm ocean temperatures in the mid latitudes in the North
Pacific has continued to shift eastward with time, and ocean
temperatures are above climatology along the west coast of Canada.
This is different from what was observed in 2012 and 2013 and may
favor northwest flow aloft across the Central Plains and increased
incidence of nocturnal thunderstorm clusters propagating from
northeastern Colorado across western Kansas this summer. Guidance
still suggests that rainfall in June will be above climatology,
especially in northern Kansas.
In the more immediate future, the numerical models are in
surprisingly good agreement with propagation of the closed upper
level cyclone as it approaches the Oklahoma Panhandle Monday and
moves into northern Oklahoma Tuesday. The 12Z GFS agrees well with
the 00Z ECMWF and largely was used for minor grid adjustments. A
moist and marginally unstable atmosphere will continue in western
Kansas, and minor troughs rotating around the upper level cyclone
will support episodes of thunderstorms with locally heavy rainfall.
The GFS and ECMWF both move a minor upper level trough evident on
satellite imagery in central California around the upper level
cyclone into western Oklahoma Sunday night. This should support
development of a cluster of thunderstorms that will move into south
central Kansas Sunday night and weaken in central Kansas Monday
morning. Scattered thunderstorms in the vicinity of the upper level
cold pool could occur about any where in Kansas Monday afternoon and
Monday evening, although the cold pool across the southern part of
the state may be the favored area for more widespread showers and
thunderstorms. Any weak boundary near the upper level cyclone will
have to be watched for the possibility weak nonmesocyclone tornado
formation in the moist environment.
On Tuesday, the upper level cyclone still will be close enough to
south central Kansas to support diurnally modulated thunderstorm
development, but chances will decrease Wednesday and Thursday as
upper level ridging builds in eastern Colorado and western Kansas.
The GFS continues to try to bring the remnants of TS Amanda north
into Arizona Friday and into eastern Colorado by Saturday morning,
while the ECMWF carries most of the remnants of Amanda west into the
cooler waters of the Pacific. If the GFS verifies, there will be an
increased chance for thunderstorms in western Kansas Saturday;
however, confidence is far too low to get too carried away with rain
chances. Upper level ridging will build in central Canada around 1
June, and a cold front is likely to move into northern Kansas. A
warm mid level plume should spread into the High Plains next
weekend, and the potential exists for nocturnal thunderstorm
clusters along the edge of the elevated mixed layer the few days of
June.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 655 AM CDT SAT MAY 24 2014
IFR to LIFR ceilings will persist through much of the morning before
lifting into the MVFR and VFR categories. Areas of fog around Garden
City will reduce visibilities to less than a mile for a few hours
this morning as well. Isolated light rainshowers will be possible
around Garden City and Dodge City late this morning with a chance
for thunderstorms developing early this evening.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 61 79 58 / 40 50 40 50
GCK 79 58 79 57 / 40 50 30 40
EHA 77 57 78 56 / 40 50 30 40
LBL 79 60 80 57 / 40 50 40 40
HYS 78 60 80 59 / 40 50 40 50
P28 80 63 78 62 / 40 50 40 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Gerard
SHORT TERM...Russell
LONG TERM...Ruthi
AVIATION...Gerard
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 PM EDT SAT MAY 24 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 340 PM EDT SAT MAY 24 2014
18Z SFC ANALYSIS SHOWS COOL CANADIAN HIGH PRESSURE IN CONTROL OF THE
WEATHER THROUGHOUT THE OHIO VALLEY. THIS HAS KEPT THE SKIES CLEAR
OVER EAST KENTUCKY AND WINDS LIGHT. TEMPERATURES HAVE MADE IT TO THE
LOW AND MID 70S WHILE DEWPOINTS HAVE REMAINED IN THE QUITE
COMFORTABLE RANGE OF UPPER 40S TO LOWER 50S.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS THEY
ALL DEPICT THE EASTWARD DRIFT OF A WEAK RIDGE OVER THE DEEP SOUTH.
THIS TAKES PLACE...AS THE BLOCKY PATTERN CONTINUES...ANCHORED BY
LOWS OVER THE FOUR CORNERS REGION AND OFF THE NORTHEAST COAST. THE
RIDGE IS NOT STRONG ENOUGH TO KEEP ALL THE ENERGY AT BAY FOR
KENTUCKY...THOUGH...SUCH THAT SOME WORKS INTO OUR CWA BY MIDDAY
MONDAY. GIVEN THE MODEL SIMILARITIES HAVE GONE WITH WX DETAILS FROM
THE NAM12 THROUGH MONDAY MORNING...FAVORING THE HRRR FOR THE FIRST 24
HOURS.
SENSIBLE WEATHER WILL FEATURE ANOTHER COOL NIGHT UNDER MOSTLY CLEAR
SKIES AND MINIMAL FOG FORMATION. A MODERATE TO LARGE RIDGE AND VALLEY
TEMP SPLIT CAN BE EXPECTED GIVEN THE GOOD RADIATIONAL COOLING
CONDITIONS. HAVE ADJUSTED THE TEMPERATURES AND NIGHT TIME DIURNAL
CURVES FOR THIS IN THE VALLEYS. THE FRONT JUST OFF TO THE SOUTH AND
WEST WILL START TO MOVE BACK NORTH ON SUNDAY BRINGING A FEW MORE
CLOUDS INTO EAST KENTUCKY AND A SMALL INCREASE IN THE DEWPOINTS.
TEMPERATURES WILL BE WARMER WITH READINGS TOPPING OUT IN THE UPPER
70S AND LOWER 80S ON SUNDAY. EXPECT ANOTHER RIDGE TO VALLEY SPLIT ON
SUNDAY NIGHT...THOUGH A BIT MORE CLOUD COVER SHOULD MITIGATE THE
COOLING IN THE VALLEYS.
PRIMARILY USED THE BCCONSSHORT GRIDS AS A STARTING POINT FOR TEMPS...
DEWPOINTS...AND WINDS THROUGH THE FIRST 24 HOURS WITH THE BCCONSALL
THEN LOADED TO THE END OF THE SHORT TERM. MOST OF THE ADJUSTMENTS
WHERE MADE TO ACCOUNT FOR TERRAIN DIFFERENCES IN THE LOWS TONIGHT AND
TO A CERTAIN EXTENT ON SUNDAY NIGHT. AS FOR POPS...ENDED UP IN LINE
WITH THE MOS NUMBERS THROUGH SUNDAY...HOLDING IN THE LOW SINGLE
DIGITS. FOR SUNDAY NIGHT THE HIGHER VALUES AT SME FROM THE MAV WERE
DISCOUNTED IN FAVOR OF THE DRIER MET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 305 PM EDT SAT MAY 24 2014
THE MODELS REMAIN IN GOOD AGREEMENT WITH THE AMPLIFIED LONG WAVE
PATTERN ACROSS THE CONUS THROUGH THE PERIOD. AN UPPER LEVEL LOW
PRESSURE SYSTEM WILL START OUT JUST EAST OF THE FOUR CORNERS...WITH
RIDGING ALIGNED ALONG THE MISSISSIPPI VALLEY...AND TROUGHING ACROSS
SOUTHEASTERN CANADA AND NEW ENGLAND. THE UPPER LEVEL LOW WILL
UNDERCUT THE RIDGE AXIS AS IT SLOWLY MEANDERS INTO THE SOUTHERN
PLAINS. MEANWHILE...ANOTHER DEEPER LOW WILL BE MOVING INTO THE
PACIFIC NORTHWEST...HELPING TO TIGHTEN UP A RIDGE ACROSS THE ROCKIES
AND PLAINS...WITH REINFORCING BOUTS OF TROUGHINESS ACROSS NEW
ENGLAND AND SOUTHEASTERN CANADA. THE DETAILS ON HOW ALL OF THIS WILL
EVOLVE CONTINUE TO BE A LITTLE MURKY BEYOND THE MIDDLE OF NEXT
WEEK...SO WILL STICK CLOSE TO A MODEL BLEND...ALTHOUGH DID NOT GO
QUITE AS AGGRESSIVE AS THE GIVEN POPS SINCE THERE ARE NO STRONG
FORCING SIGNALS TO CONTEND WITH ACROSS OUR AREA.
FOR EASTERN KENTUCKY...EXPECT INCREASED HUMIDITY AND THE THREAT OF
MAINLY AFTERNOON AND EVENING CONVECTION EACH DAY THROUGH THE END OF
THE WORK WEEK...AS THE RIDGE GRADUALLY BREAKS DOWN IN THE WAKE
OF THE NEARING UPPER LEVEL LOW. HIGHS WILL TOP OUT IN THE LOW TO MID
80S...WITH LOWS IN THE 60S. ADDITIONALLY...A WEAK SURFACE BOUNDARY
WILL GRADUALLY DRAW CLOSER FROM THE NORTH AND NORTHEAST THROUGH
THURSDAY...ADDING A LITTLE BIT MORE FORCING POTENTIAL. BY LATE
FRIDAY...RIDGING WILL BEGIN TO TAKE HOLD ONCE AGAIN ACROSS THE OHIO
VALLEY...WITH SLIGHTLY DRIER AND COOLER AIR ARRIVING BEHIND THE WEAK
FRONTAL BOUNDARY BY THEN MOVING INTO THE TENNESSEE VALLEY. WILL KEEP
SATURDAY DRY AS THE SURFACE BOUNDARY CONTINUES TO PUSH FURTHER SOUTH
WHILE RIDGING BUILDS IN ALOFT. HIGHS WILL BE SLIGHTLY COOLER BY NEXT
WEEKEND WITH HIGHS AROUND 80...AND LOWS IN THE LOWER 60S...ALTHOUGH
A FEW SHELTERED VALLEYS COULD MAKE IT INTO THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 130 PM EDT SAT MAY 24 2014
VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 TO 36 HOURS. SOME PATCHY
MVFR FOG COULD DEVELOP LATE TONIGHT NEAR THE RIVER BEDS...BUT WILL
NOT IMPACT AIRPORTS ACROSS THE AREA. WINDS WILL BE LIGHT AND VARIABLE
THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...GEOGERIAN
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 PM EDT SAT MAY 24 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 435 PM EDT SAT MAY 24 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER CNTRL
NAMERICA. RIDGE IS SUPPORTING SFC HIGH PRES OVER THE GREAT LAKES
THIS AFTN...AND AS A RESULT...LAKE BREEZES ARE THE RULE NEAR LAKE
SUPERIOR AND LAKE MICHIGAN. PER 12Z KGRB SOUNDING...AIR MASS IS TOO
DRY/STABLE TO SUPPORT ANY CONVECTION ALONG AHEAD OF LAKE BREEZE
BOUNDARIES. IN FACT...THERE HASN`T BEEN TOO MUCH CU TODAY. WHAT HAS
DEVELOPED IS VERY HIGH BASED DUE TO THE DRY LOW-LEVELS. EARLIER
TODAY...THERE WERE A FEW SHRA IN NE MN AND FAR NE LAKE
SUPERIOR/ADJACENT ONTARIO IN AREAS OF 850-700MB THETA-E ADVECTION.
THOSE SHRA HAVE MOSTLY DISSIPATED THIS AFTN. TEMPS ACROSS W AND
CNTRL UPPER MI HAVE RISEN WELL INTO THE 70S AND LWR 80S AWAY FROM
LAKE MODERATION.
IN THE SHORT TERM...MAIN CONCERN INVOLVES POTENTIAL OF ANY
CONVECTION TONIGHT/SUN. OVER THE NEXT 24 HRS...MID/UPPER RIDGE TO
THE W DRIFTS SLIGHTLY E...WITH AXIS STILL JUST W OF UPPER MI BY LATE
SUN AFTN. 500MB HEIGHTS CHANGE LITTLE...AND IF ANYTHING THERE ARE
VERY SLIGHT RISES. OVERALL...THIS SUGGESTS LIMITED POTENTIAL FOR
PCPN. HOWEVER...A SUBTLE SHORTWAVE IS EXPECTED TO ROUND THE RIDGE.
THIS SHORTWAVE APPEARS TO BE RESPONSIBLE FOR THE CONVECTION
CURRENTLY DEVELOPING IN SRN MANITOBA. QUESTION IS WHETHER THIS
CONVECTION WILL PERSIST AS IT MOVES AWAY FROM INSTABILITY (MLCAPES
ARE AROUND 1500J/KG IN SRN MANITOBA WHERE CONVECTION IS CURRENTLY
DEVELOPING). MODELS SHOW ONLY WEAK THETA-E ADVECTION TONIGHT OVER
UPPER MI...AND POOL OF ELEVATED INSTABILITY PASSES TO THE N OF UPPER
MI...FARTHER N THAN PREVIOUS GFS/NAM/GEM MODEL RUNS SHOWED. HIGH RES
MODELS ALSO KEEP PCPN FARTHER N OVER NRN LAKE SUPERIOR. AT THIS
POINT...WILL KEEP CHC/SCHC POPS N OF UPPER MI AND OVER NRN PORTIONS
OF LAKE SUPERIOR LATER TONIGHT/SUN MORNING. STILL...WILL NEED TO
WATCH TRENDS ON UPSTREAM CONVECTION AS DECAYING REMNANTS MAY SNEAK
INTO PORTIONS OF NRN UPPER MI SUN MORNING AS THICKNESS FIELDS
INDICATE PCPN WILL TEND TO PEEL SE WITH TIME.
ON SUN...POOL OF LOWER THETA-E/K INDEX ROTATES NE INTO UPPER MI.
THIS DRIER/MORE STABLE AIR ALSO RESULTS IN ALMOST NO MLCAPE PER
NAM/GFS. SO THERE SHOULDN`T BE ANY CONCERN WITH CONVECTION
DEVELOPING DURING DAYTIME HEATING. AS FOR TEMPS...DEEP MIXING TOWARD
750MB ON NAM/GFS FCST SOUNDINGS SUGGESTS MAX TEMPS INTO THE LWR TO
EVEN MID 80S AWAY FROM LAKE MODERATION. SW FLOW IS A LITTLE STRONGER
SUN THAN TODAY...SO THERE WILL ONLY BE LOCAL COOLING NEAR LAKE
SUPERIOR. SIMILAR TO TODAY...LAKESIDE LOCATIONS ALONG LAKE
MICHIGAN...ESPECIALLY E OF KESC SHOULD ONLY SEE HIGH TEMPS IN THE
50S AT BEST. WITH DEEP MIXING...INCORPORATED LOWER DWPTS INTO THE
FCST IN THE AFTN BASED ON SOUNDINGS. DWPTS COULD VERY WELL END UP A
FEW DEGREES LOWER THAN FCST BASED ON MIXING POTENTIAL. AS A RESULT
OF MAX TEMPS INTO THE LWR 80S AND DWPTS FALLING TO THE LWR 40S...
MIN RH WILL FALL TO AS LOW AS AROUND 25PCT. FORTUNATELY...WINDS WILL
STILL REMAIN RELATIVELY LIGHT...ESPECIALLY WHERE LOWEST RH WILL
OCCUR.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 435 PM EDT SAT MAY 24 2014
THE MORE SEASONABLE UPPER PATTERN WILL CONTINUE ACROSS THE REGION
THROUGH THE NEXT WEEK...WITH THE MAIN JET REMAINING ACROSS CANADA
THROUGH THE PERIOD. THE UPPER MIDWEST AND WESTRN GREAT LAKES WILL
REMAIN UNDER THE INFLUENCE OF A BROAD RIDGE THROUGH MUCH OF THE
PERIOD WHICH WILL MEAN THAT ANY PRECIPITAITON CHANCES WILL BE TIED
TO RELATIVELY WEAK AND HARD TO FORECAST DISTURBANCES IN THE
NORTHWESTERLY UPPER FLOW ALOFT.
THE QUIET AND PLEASANT WEATHER TODAY INTO SUNDAY WILL CONTINUE INTO
SUNDAY NIGHT AS THE SFC PRESSURE RIDGE REMAINS ACROSS THE GREAT
LAKES. HOWEVER...AS THE NIGHT GOES ON...THE HIGH WILL SHIFT SE OF
THE AREA WHICH WILL ALLOW FOR RETURN FLOW TO DEVELOP OVERNIGHT AS
THE SURFACE FRONT OVER SOUTHERN CANADA GRADUALLY MOVES INTO NRN MN.
THE MODELS HAVE BACKED OFF ANY PCPN MOVING INTO THE AREA OVERNIGHT
SUNDAY...AND AS SUCH HAVE REMOVED ALL MENTION OF PCPN EXCEPT FOR THE
FAR WEST LATE.
ON MONDAY...A DISTURBANCE MOVING THROUGH IN W-NW FLOW ALOFT WILL
ALLOW THE WEAK COLD FRONT TO MOVE MOVING ACROSS THE LAKE LATER IN
THE AFTN INTO EVE. IN GENERAL...THE SFC BASED INSTABILITY TOO GREAT
IN MODELS DUE TO OVER FORECAST OF SFC DWPTS IN MID 60S. MLCAPE
GENERALLY AROUND 500 J/KG IN MOST OF THE NWP WHICH IS STILL LIKELY A
LITTLE HIGH GIVEN THAT MID LVL LAPSE RATES REMAIN QUITE WEAK - ONLY
AROUND 5.5 C/KM. STILL...THE COMBINATION OF INCREASED MOISTURE
ADVECTION AND ANY ADDITIONAL LIFT FROM LAKE BREEZES COULD ALLOW
SHOWERS AND THUNDERSTORMS TO DEVELOP. AS SUCH...WILL KEEP CHC POPS
ACROSS THE ENTIRE FORECAST AREA DURING THE DAY EXCEPT THOSE AREAS IN
THE KEWEENAW WHERE THE LAKE INDUCED STABILITY WILL PRECLUDE ANY
CONVECTIVE DEVELOPMENT. DO NOT THINK MEMORIAL DAY WILL BE A WASHOUT
IN ANY WAY...BUT PEOPLE WITH OUTDOOR ACTIVITIES MAY HAVE TO DODGE A
FEW SHOWERS/STORMS THROUGH THE DAY. WILL BE ANOTHER MILD DAY WITH
850MB TEMPS AROUND +14C. WITH SHOWERS/STORMS AND SOME CLOUDS IT MAY
NOT BE QUITE AS WARM AS SUNDAY...BUT STILL AN ABOVE AVERAGE DAY FOR
THIS TIME OF YEAR.
MON NIGHT AND TUESDAY...THE COLD FRONT MOVES SOUTH AND STALLS JUST
SOUTH OF THE AREA TUESDAY. THE NAM REMAINS MUCH SLOWER WITH THE
SOUTHWARD PROGRESSION OF THE FRONT...BUT THE EXPECTATION IS THAT THE
COLD LAKE WILL ALLOW THE FRONT TO MOVE SOUTHWARD FASTER THAN THE NAM
SUGGESTS. WITH THE BEST FOCUS FOR PCPN BEING ASSOCIATED WITH THE
FRONT...AM THINKING THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE
CLOSER TO THE WISCONSIN BORDER DURING THE DAY ON TUESDAY. WILL
INCLUDE A LOW CHANCE POP DURING THE AFTERNOON ON TUESDAY FOR THOSE
AREAS. OTHERWISE...THE DEVELOPING RELATIVELY STABLE NE BOUNDARY
LAYER FLOW SHOULD KEEP MOST OF THE AREA RAIN FREE...WITH COOLER
TEMPS.
EXTENDED - SEASONABLE NW FLOW ALOFT WITH HIGH PRES RIDGE ACROSS THE
AREA SHOULD KEEP THE AREA GENERALLY DRY. TEMPS WILL BE SEASONABLE
THROUGH MID WEEK GIVEN THE NORTHEASTERLY LOW LEVEL FLOW WITH TEMPS
DURING THE DAY IN THE MID 60S-MID 70S. GFS SUGGESTS SMALL CHANCES
FOR PCPN EACH DAY BUT THIS SEEMS OVERDONE GIVEN THE STABLE SURFACE
FLOW. THE LATEST ECMWF TRIES TO REALLY BUILD THE UPPER RIDGE ACROSS
THE AREA FOR THE END OF THE WEEK...AND ALSO ALLOWS FOR MOISTURE TO
RETURN INTO THE AREA BY SATURDAY. WILL END UP INTRODUCING A CHANCE
FOR SHOWERS AND THUNDERSTORMS ON SATURDAY. OTHERWISE...IT LOOKS LIKE
TEMPS WILL RISE ABOVE NORMAL ONCE AGAIN FOR NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 105 PM EDT SAT MAY 24 2014
ALTHOUGH SFC HIGH PRES OVER THE GREAT LAKES WILL SLOWLY DRIFT E AND
SE OVER THE NEXT 24HRS...LOW-LEVELS WILL REMAIN DRY...ENSURING VFR
CONDITIONS PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD. A FEW
SHRA MAY DEVELOP TO THE N OF UPPER MI TONIGHT. WHILE THE SHRA WILL
BE MOVING SE...IT APPEARS ATTM THAT THE SHOWERS WILL DEVELOP FAR
ENOUGH TO THE N THAT THEY WILL NOT IMPACT ANY OF THE TERMINALS LATE
TONIGHT/SUN MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EDT SAT MAY 24 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER 20KT TO
PREVAIL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MRD
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DULUTH MN
321 PM CDT SAT MAY 24 2014
.SYNOPSIS...
ISSUED AT 305 PM CDT SAT MAY 24 2014
INITIAL SHORTWAVE THAT CRESTED THE TOP OF THE MID LVL RIDGE EARLY
TODAY HAS SHIFTED EAST OF THE REGION. A COMBINATION OF
ANTICYCLONIC BDRY LYR FLOW AND MID LVL WARMING HAS RESTRICTED
ADDITIONAL CONVECTIVE DEVELOPMENT SO FAR THIS AFTERNOON. LATEST
VIS IMAGERY SHOWS SOME CU BUILDING OVER ARROWHEAD. THIS IS
OCCURRING WITHIN AN AREA OF HIGHER 85/70H LAPSE RATES PER THE
LATEST RUC13 ANALYSIS. WE MAY YET SEE AN ISOLATED RW/TRW DEVELOP.
TEMPS JUMPED QUICKLY INTO THE 70S AND 80S TODAY EXCEPT MUCH COOLER
NEAR LAKE SUPERIOR.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 305 PM CDT SAT MAY 24 2014
TONIGHT/TOMORROW...ITS CONVECTIVE SEASON AND WITH THAT COMES THE
USUAL CHALLENGE OF FCSTING PRECIP CHANCES IN THE ABSENCE OF WELL
DEFINED BDRY LYR CONVERGENCE. THE BASIC SYNOPTIC SCALE PATTERN
REMAINS RELATIVELY THE SAME DURING THE NEXT 24 HRS. MID LVL WARMING
WILL CONTINUE OVER THE AREA AMIDST A STRONG MID LVL RIDGE. THE
ASSOCIATED LARGE SFC HIGH WILL PREVAIL IN THE LOW LEVELS. THE BASIC
SPAGHETTI PLOTS OF MULTI MDL QPF CONCENTRATE THE MAJORITY OF PRECIP
WEST OF THE CWA THROUGH SUNDAY AFTERNOON. HAVE TRIMMED POPS WEST PER
LATEST SREF/GEM/NAM CONSENSUS. EVEN 4KM SPC WRFNMM..WHICH IS A
CONVECTION ALLOWING MODEL...DOESNT ALLOW CONVECTION THIS PERIOD. MAX
TEMPS SUNDAY REMAIN ABOVE CLIMO BASED ON LATEST FCST 925H VALUES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 PM CDT SAT MAY 24 2014
A WEAK LOW PRESSURE AREA AND COLD FRONT WILL BE THE FOCUS FOR
SHOWERS AND THUNDERSTORMS EARLY THIS WEEK. THE FRONT WILL MAKE IT TO
NORTHWEST MN THEN EITHER MOVE SOUTH OF THE CWA BEFORE BECOMING
QUASI-STATIONARY OR BECOME STATIONARY ACROSS NORTHERN MN. WHERE IT
SLOWS IS WHERE THE BEST CHANCE FOR STORMS WILL BE...WITH THE GFS AND
ECMWF IN BETTER AGREEMENT THAT THE NAM WITH RESPECT TO THE FRONTAL
POSITION BY TUESDAY. WITH INCREASING MOISTURE AND WARM AIR ADVECTION
THERE WILL BE INCREASING CHANCES OF THUNDERSTORMS...ESPECIALLY LATE
SUNDAY NIGHT AS LOW LVL JET INCREASES. ATMOS DESTABILIZES WITH CAPES
OF 1500 TO 2000 J/KG WITH STRONG WAA JUST AHEAD OF THE FRONT. BY
ABOUT TUESDAY THERE IS GOOD AGREEMENT THAT THERE WILL BE A WEAK
BOUNDARY SET UP ACROSS THE SRN PORTION OF THE FORECAST
AREA...PUTTING MUCH OF THE NORTHLAND IN CONTINUING CHANCES OF
THUNDERSTORMS NORTH OF THE BOUNDARY FOR THE REMAINDER OF THE WEEK.
THIS WILL ALSO MEAN OFF-LAKE WINDS AND COOLER TEMPS IN THE TWIN
PORTS AND THE NORTH SHORE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1234 PM CDT SAT MAY 24 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SOME SPOTTY -TSHRA
POSSIBLE FOR KINL F0R A FEW HOURS LATE THIS AFTNOON...BUT THEN DRY
CONDITIONS EXPECTED TO RETURN. SOUTH WINDS TODAY TO INCREASE TO
10-12KTS FOR MUCH OF THE DAY...THEN DROPPING OFF AGAIN AROUND
SUNSET TO NEARLY CALM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 56 79 60 78 / 10 10 60 20
INL 59 82 57 78 / 20 10 40 10
BRD 58 81 62 80 / 10 20 50 20
HYR 52 81 61 80 / 10 10 60 30
ASX 51 79 59 79 / 0 10 60 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...CLC
AVIATION...CLC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1237 PM CDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1045 AM CDT SAT MAY 24 2014
INITIAL WAA SHOWERS HAVE DIMINISHED OVER ARROWHEAD WITH REMNANT
CLOUDS THINNING. TRIMMED POPS THROUGH EARLY AFTERNOON BEFORE
POSSIBLE REDEVELOPMENT OVER BORDERLAND. LATEST HRRR 3KM SUGGESTS
VERY LITTLE ACTIVITY WHILE 12KM NAM IS MORE AGGRESSIVE WITH
CONVECTION. HAVE KEPT LOW POPS OVER ARROWHEAD/BORDERLAND FOR AFTN.
OTHERWISE RAISED MAX TEMPS BASED ON LATEST 92H TEMPS AND EXPECTED
SUNSHINE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT SAT MAY 24 2014
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE POTENTIAL
FOR SHOWERS AND STORMS...MAINLY ACROSS NE MN TODAY THROUGH
SUNDAY...AND THE ABOVE AVERAGE TEMPERATURES THIS HOLIDAY WEEKEND
WITH SLIGHTLY COOLER CONDITIONS AROUND THE IMMEDIATE LAKE SHORE.
DOMINATE SYNOPTIC FEATURE PRESENT ACROSS THE UPPER MIDWEST IN THE
FORM OF A HIGH AMPLITUDE UPPER RIDGE WITH AN ASSOCIATED WARM AIR
MASS AND SFC HIGH MOVING THROUGH THE GREAT LAKES. SOUTHERLY FLOW
ON THE WEST SIDE OF THE HIGH IS HELPING USHER IN THIS RELATIVELY
WARM AND HUMID AIR INTO THE NORTHLAND THIS WEEKEND. A WEAK/WWD
EXTENDING BRANCH OF THE SFC RIDGE WILL LINGER ACROSS NRN MN/WI
TODAY AND SUNDAY...AND SLIGHTLY DELAY THE APPROACHING SFC TROUGH
OVER THE PLAINS UNTIL MEMORIAL DAY. A COUPLE UPPER SHRT WVS WILL
RIDE ALONG THE NRN/NWRN EDGE OF THE UPPER RIDGE TODAY AND
TONIGHT...KICKING OFF LIGHT RAIN SHOWERS WITH POSSIBLY A FEW
ISOLATED WEAK STORMS. CURRENTLY THERE ARE A FEW RADAR RETURNS
SHOWING UP FROM BIG FALLS TO BRAINERD THIS MORNING ALONG A WEAK
BAND OF MID-LVL F-GEN...BUT THESE SHOWERS SHOULD DIMINISH IN
INTENSITY AND COVERAGE AS THEY MOVE EWD INTO THE DRIER AIR LATER
THIS MORNING.
ADDITIONAL SHOWERS AND ISOLATED STORMS COULD DEVELOP ALONG THE
INTERNATIONAL BORDER THIS AFTERNOON/EVENING TODAY AS THE BL
DESTABILIZES AND WEAK UPPER FORCING TRIGGERS CONVECTION ALONG AN
INSTABILITY GRADIENT ACROSS NRN MN. TEMPERATURES WILL WARM INTO
THE 70S AGAIN TODAY WITH A FEW LOWER 80S ACROSS NE MN. COOLER
CONDITIONS WILL BE FELT ALONG THE IMMEDIATE LAKE SHORE AREAS OF
LS. S/SW WINDS ACROSS LS THIS MORNING AND MOST OF THE AFTERNOON
WILL KEEP AREAS ALONG THE NORTH SHORE...NORTH OF SILVER BAY RATHER
CHILLY WITH MOST OF THE SOUTH SHORE WARMING UP INTO THE 70S.
HOWEVER...A WEAK NELY FLOW OVER THE HEAD OF THE LAKE COULD
POSSIBLY DEVELOP LATE THIS AFTERNOON AND INTO THE EVENING AND DROP
TEMPS AROUND DULUTH/SUPERIOR TO TWO HARBORS A QUICK 10 TO 15
DEGREES IN A SHORT PERIOD OF TIME. THE LAKE BREEZE WILL NOT HAVE
MUCH OF AN IMPACT ON INLAND AREAS...MAINLY JUST THE IMMEDIATE
LAKESHORE LOCATIONS.
ANOTHER LLJ IS EXPECTED TO DEVELOP TONIGHT AND ALLOW WEAK CONVECTION
TO PERSIST OVER FAR NRN/NERN MN. THE COVERAGE AND INTENSITY OF THE
SHOWERS/STORMS IS DIFFICULT TO DETERMINE AT THIS POINT...WITH THE
MAIN AREA OF PRECIP LIKELY HOLDING OFF TO THE WEST THROUGH SUNDAY
MORNING. THE ORIENTATION OF THE SFC HIGH AND APPROACHING TROUGH
FROM THE W/NW WILL KEEP THE WIND FLOW FROM THE SW AND PREVENT THE
DEVELOPMENT OF A STRONG LAKE BREEZE ON SUNDAY AS THE TROUGH
APPROACHES. TEMPERATURES WILL ONCE AGAIN WARM INTO THE 70S AND
LOWER 80S...WITH DWPTS RISING INTO THE 50S AND LOWER 60S.
CONDITIONS WILL FEEL MORE HOT AND HUMID ON SUNDAY WITH A BETTER
CHANCE OF SHOWERS AND STORMS IN THE AFTERNOON...ESPECIALLY OVER
THE WRN COUNTIES IN NE MN. T-STORMS ON SUN AFTERNOON COULD BECOME
STRONG THROUGH NE MN AS BL CAPE VALUES APPROACH 1000 J/KG AND A
MORE ROBUST SURGE OF MOIST AIR ARRIVES ALONG THE NOSE OF A STRONG
AREA OF MOISTURE TRANSPORT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 335 AM CDT SAT MAY 24 2014
SUNDAY NIGHT AND MONDAY A SHORTWAVE AND A SURFACE COLD FRONT WILL
DRAG ACROSS THE AREA...BRINGING A CHANCE FOR SHOWERS AND
THUNDERSTORMS. THE FRONT STALLS OVER THE AREA MONDAY NIGHT...AND
MAY SERVE AS THE FOCUS FOR MORE SHOWERS AND THUNDERSTORMS. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS IS SUNDAY NIGHT AND EARLY
MONDAY. TEMPERATURES THROUGH THE PERIOD TO REMAIN WARM WITH DEEP
MIXING ON MONDAY TO ALLOW TEMPERATURES TO RISE INTO THE UPPER 70S TO
AROUND 80...WHICH WILL BE A GOOD 10 DEGREES ABOVE NORMAL.
TUESDAY THROUGH FRIDAY THERE WILL BE A WEAK SEMI-CUT OFF UPPER LOW
IN THE SOUTHERN STREAM OF OUR SPLIT UPPER LEVEL FLOW THAT SLOWLY
WOBBLES EAST...THEN SOUTHEAST DURING THE WEEK. AN UPPER LEVEL RIDGE
BUILDS OVER THE MIDWEST IN THE NORTHERN STREAM DURING THE
WEEK...BRINGING WARM TEMPERATURES AND CHANCES FOR SHOWERS AND
THUNDERSTORMS TO THE FORECAST AREA ON AND OFF DURING THE WORK WEEK.
TEMPERATURES THROUGH THE WEEK WILL BE 5 TO 10 DEGREES ABOVE NORMAL
THROUGH THE PERIOD. HAVE MAINLY USED A CONSENSUS APPROACH TO THE
FORECAST...THOUGH IN GENERAL FAVOR THE ECMWF SOLUTION AND HAVE
ADJUSTED THAT DIRECTION FOR A FEW PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1234 PM CDT SAT MAY 24 2014
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SOME SPOTTY -TSHRA
POSSIBLE FOR KINLFRO A FEW HOURS LATE THIS AFTNOON...BUT THEN DRY
CONDITIONS EXPECTED TO RETURN. SOUTH WINDS TODAY TO INCREASE TO
10-12KTS FOR MUCH OF THE DAY...THEN DROPPING OFF AGAIN AROUND
SUNSET TO NEARLY CALM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 80 56 78 60 / 10 10 10 60
INL 83 59 81 57 / 20 20 40 70
BRD 82 58 80 62 / 10 10 50 70
HYR 79 52 80 61 / 0 10 10 60
ASX 79 51 78 59 / 10 0 10 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...BJT
LONG TERM...LE
AVIATION...CLC
AREA FORECAST DISCUSSION
NWS BILLINGS MT
248 PM MDT SAT MAY 24 2014
.SHORT TERM...VALID FOR SUN AND MON...
THUNDERSTORMS ARE STILL EXPECTED TO DEVELOP ACROSS THE AREA THIS
AFTERNOON AND EVENING. A PACIFIC FRONT TIED TO A WEAK SHORTWAVE
APPROACHING FROM THE WEST WILL BE THE FOCUS FOR CONVECTION TO
DEVELOP THIS AFTERNOON AND PROGRESS EASTWARD INTO THE CENTRAL
PORTIONS OF THE FORECAST AREA BY THIS EVENING. ACROSS SOUTHEAST
MONTANA...A DIFFERENT WEAK SHORTWAVE EJECTING OUT OF WYOMING WILL
PRODUCE SCATTERED CONVECTION THERE THIS AFTERNOON...BEFORE IT
SHIFTS INTO THE DAKOTAS BY THIS EVENING.
AS OF 20Z...THUNDERSTORMS WERE DEVELOPING OVER THE HIGHER TERRAIN
TO OUR WEST...AND JUST AHEAD OF THE WEAK SHORTWAVE TROUGH PUSHING
INTO WESTERN MONTANA. MESOANALYSIS INDICATES 500 TO 1500 J/KG
MLCAPE...WITH HIGHEST VALUES ACROSS FAR EASTERN MONTANA WHERE
SURFACE DEW POINTS ARE IN THE MID-50S. THUNDERSTORMS WERE ALSO
STARTING TO DEVELOP ACROSS THE BLACK HILLS AND BACK ALONG THE
HIGHER TERRAIN INTO SOUTHEAST MONTANA. SHEAR REMAIN MEAGER ACROSS
THE FORECAST AREA...WITH 0-6 KM SHEAR APPROACHING 30 KTS ACROSS
THE NORTHWEST PORTION OF THE FORECAST AREA...AND ONLY ABOUT 20
KTS ACROSS THE SOUTHEAST. THUS...EXPECT VERY LOOSELY ORGANIZED
STORM STRUCTURES THIS AFTERNOON. PERHAPS THE BEST CHANCE AT SOME
ORGANIZATION WILL BE FROM THE NORTHWEST CORNER OF THE CWA TOWARD
BILLINGS THIS EVENING...AS THE SHEAR NEAR 30 KTS WILL HELP TO
ORGANIZE SOME MULTICELLAR CLUSTERS. THUS THE THREAT FOR SEVERE
STORMS REMAINS LOW...WITH MAINLY SMALL HAIL EXPECTED. THE STORM
MOTIONS WILL ALSO BE SLOW WITH THE LACK OF A STRONG STEERING FLOW.
THAT COMBINED WITH PW VALUES 0.75 INCHES TO AROUND 1 INCH IN THE
EAST...WILL RESULT IN A HEAVY RAIN THREAT WITH THE STORMS. GIVEN
THE STEEP MID-LEVEL LAPSE RATES...DECENT HAIL CAPE AND COOL
TEMPERATURES ALOFT...EXPECT THAT SOME ISOLATED OCCURRENCES OF
LOW- END SEVERE HAIL IS POSSIBLE...BUT THE OVERALL LACK OF SHEAR
AND STORM ORGANIZATION WILL KEEP THIS FROM BEING A WIDESPREAD
THREAT. AN AXIS OF DCAPES APPROACHING 1000 J/KG IS ALSO ANALYZED
ON MESOANALYSIS...WHICH MATCHES WITH THE INVERTED-V RAP SOUNDING
FOR KBIL. THUS CAN ALSO NOT RULE OUT SOME GUSTY WINDS WITH SOME OF
THE STRONGER STORMS.
SUNDAY WILL BE A QUIETER DAY ACROSS THE FORECAST AREA BEHIND THE
PACIFIC COLD FRONT. TEMPERATURES WILL BE SLIGHTLY COOLER BEHIND
THE FRONT...BUT WILL STILL REACH INTO THE MID TO UPPER 70S. THE
FLOW ALOFT TURNS MORE SOUTHERLY ON MONDAY...AND THE LOW-LEVEL FLOW
WILL TURN BACK AROUND THE TO EAST WHICH WILL HELP INCREASE THE
LOW-LEVEL MOISTURE AVAILABLE. MODELS WANT TO BRING A WEAK
SHORTWAVE ACROSS THE AREA IN THE SOUTHWESTERLY FLOW MONDAY
EVENING...PRODUCING OUR NEXT CHANCE AT SOME THUNDERSTORMS. SHEAR
COULD BE A LITTLE BETTER ON MONDAY THAN TODAY SO WILL HAVE TO
WATCH FOR PERHAPS A LITTLE BETTER STORM ORGANIZATION MONDAY
EVENING.
TEMPERATURES WILL REMAIN WARM THROUGH THE EXTENDED...WHICH WILL
CONTINUE SNOW MELT ACROSS THE AREA MOUNTAINS. THIS WILL LEAD TO
INCREASED RIVER AND STREAM FLOWS THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK.
CHURCH
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
OVERALL FORECAST REMAINS UNCHANGED IN THE EXTENDED. CONSENSUS IS
FOR AN UPPER-LEVEL LOW OVER THE PACIFIC NORTHWEST BY WEDNESDAY
INTO THURSDAY...BEFORE PUSHING NORTHEASTWARD ON FRIDAY. THIS WILL
KEEP THE FORECAST AREA IN AN OVERALL WARM SOUTHWEST FLOW PATTER
THROUGH THE MIDDLE OF THE WEEK. TEMPERATURES WILL REMAIN AT AND
ABOVE NORMAL...WHICH WILL CONTINUE HIGH-COUNTRY SNOW MELT...AND
ASSOCIATE RIVER RISES ACROSS THE AREA.
THUNDERSTORM CHANCES ARE BEST ON TUESDAY...AND SHIFT NORTH ON
WEDNESDAY AS THE SURFACE LOW IS CENTERED OVER NORTH CENTRAL
MONTANA. BEYOND WEDNESDAY...MODEL CONSENSUS IS FOR ANOTHER UPPER-LOW
TO DEVELOP OVER OREGON...KEEPING THE FORECAST AREA IN SOUTHWEST
FLOW ALOFT. TO COMPLICATE THE FORECAST...MODELS WANT TO PULL THE
REMNANTS OF HURRICANE AMANDA THROUGH THE 4 CORNERS REGION AND
ACROSS THE EASTERN PORTION OF THE FORECAST AREA...WHICH WILL
CERTAINLY HELP TO INCREASE MOISTURE AVAILABILITY. GIVEN THE
OVERALL PATTERN AND MOISTURE AVAILABILITY...CANNOT RULE OUT
THUNDERSTORMS MOST DAYS IN THE EXTENDED FORECAST.
CHURCH
&&
.AVIATION...
SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE
FORECAST AREA THIS AFTERNOON. THE MAIN THREATS WITH THESE STORMS
WILL BE SMALL HAIL...GUSTY WINDS AND SOME HEAVY RAIN. MVFR
CONDITIONS ARE EXPECTED IN THE HEAVIER STORMS DUE TO THE HEAVY
RAIN. MOUNTAIN OBSCURATIONS ARE ALSO EXPECTED DUE TO THESE STORMS.
THUNDERSTORMS WILL DIMINISH AFTER MIDNIGHT TONIGHT. OUTSIDE OF
THESE THUNDERSTORMS VFR CONDITIONS ARE EXPECTED TO PREVAIL THIS
AFTERNOON AND OVERNIGHT TONIGHT.
CHURCH
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 053/076 055/081 054/078 054/083 055/080 052/075 053/072
61/B 13/T 43/T 32/T 23/T 33/T 33/T
LVM 044/074 047/078 044/075 045/083 045/078 043/073 047/070
52/T 23/T 33/T 33/T 33/T 33/T 33/T
HDN 053/078 051/083 054/081 055/086 056/082 053/077 054/074
61/B 12/T 32/T 32/T 23/T 33/T 44/T
MLS 057/079 054/083 056/083 058/088 060/082 055/077 055/072
62/W 13/T 33/T 33/T 33/T 33/T 44/T
4BQ 055/078 054/083 055/083 057/089 059/083 055/077 054/073
52/W 12/T 33/T 33/T 23/T 34/T 44/T
BHK 056/079 052/080 055/080 057/085 059/081 053/076 055/071
62/W 13/T 33/T 33/T 23/T 33/T 44/T
SHR 050/074 047/079 049/079 050/085 054/081 050/074 050/071
52/T 23/T 32/T 22/T 23/T 34/T 43/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
138 PM PDT SAT MAY 24 2014
.SYNOPSIS...A DRYING AND WARMING TREND WILL BECOME EVIDENT THROUGH
THE REMAINDER OF THE WEEKEND AS HIGH PRESSURE TAKES HOLD ACROSS THE
REGION. TEMPERATURES ARE EXPECTED TO WARM A FEW DEGREES EACH DAY
THROUGH THE FIRST HALF OF THE WEEK...POTENTIALLY RISING TO THEIR
HIGHEST LEVELS SO FAR IN 2014.
&&
.SHORT TERM...THROUGH MONDAY NIGHT.
THE PERSISTENT NORTH TO SOUTH BAND OF SHOWERS THAT HAS BEEN DRAPED
ACROSS THE AREA CONTINUES TO [EVER SO SLOWLY] PUSH EAST THIS
AFTERNOON. VERY LIGHT RAIN HAS CONSISTENTLY BEEN REPORTED OUT OF
THESE SHOWERS BUT NOTHING HAS MEASURED SINCE EARLY THIS MORNING. IN
ANY CASE...THIS BAND WILL PUSH EAST THROUGH MOHAVE COUNTY OVERNIGHT.
TO THE NORTH...THUNDERSTORMS BEGAN TO FORM OVER NORTHERN LINCOLN
COUNTY AT 20Z THIS AFTERNOON. THE LATEST MESOANALYSIS SUGGESTS
CONVECTION WILL LIKELY DEVELOP FURTHER WEST ACROSS LINCOLN AND INTO
CENTRAL NYE COUNTY ALONG AN AXIS OF INSTABILITY AND MOISTURE
CONVERGENCE BEFORE DISSIPATING WITH THE LOSS OF HEATING THIS
EVENING. CONVECTION WILL ALSO BE POSSIBLE OVER THE SIERRA THROUGH
THIS EVENING. STORM MOTION WILL BE TO THE SOUTH-SOUTHEAST AT 10-15
MPH AND THERE IS SOME CONCERN THAT IF SHOWERS HOLD TOGETHER...WE
COULD SEE SOME LIGHT PRECIPITATION OVER CLARK COUNTY AGAIN DURING
THE LATE AFTERNOON OR EVENING. THE HRRR IS THE ONLY MODEL REALLY
ADVERTISING THIS IDEA AND FOR THE MOMENT HAVE CUT OFF THE MENTION OF
SHOWERS JUST SOUTH OF THE LINCOLN-CLARK BORDER. WILL NEED TO WATCH
THIS POTENTIAL THROUGH THE EVENING.
ANY SHOWER ACTIVITY OVER THE FORECAST AREA SHOULD BE OVER BY SUNDAY
MORNING...AND ONLY A SLIGHT CHANCE OF AFTERNOON SHOWERS EXISTS OVER
THE SIERRA AND PERHAPS FAR NORTHEAST MOHAVE COUNTY. THE BIGGER STORY
FOR SUNDAY WILL BE A MARKED INCREASE IN TEMPERATURES...WITH HIGHS
RISING 5-10 DEGREES OVER THOSE EXPERIENCED TODAY. THIS TREND WILL
CONTINUE INTO MEMORIAL DAY...WITH RISING HEIGHTS AND BETTER MIXING
ALLOWING HIGHS TO ECLIPSE 100 DEGREES ACROSS MOST OF THE LAS VEGAS
VALLEY...AND POTENTIALLY REACHING 110 IN DEATH VALLEY.
.LONG TERM...TUESDAY THROUGH SATURDAY.
ANOTHER HOT DAY IS IN STORE TUESDAY WITH THE HEAT PEAKING AS THE
RIDGE AXIS SITS OVERHEAD. ECMWF GUIDANCE CONTINUES TO ADVERTISE
HIGHS IN LAS VEGAS BETWEEN 103 AND 105. MOST OTHER GUIDANCE IS A
TOUCH COOLER THAN THAT BUT WITH ADDITIONAL HEIGHT RISES EXPECTED
TUESDAY AND NEARLY FULL SUNSHINE, TEMPERATURES SHOULD CLIMB ABOVE
MONDAYS EXPECTED HIGHS. WILL NEED TO MONITOR TEMPERATURES CLOSELY AS
105 IN THE LAS VEGAS VALLEY WOULD PUT US INTO EXCESSIVE HEAT
CRITERIA. WARM CONDITIONS PERSIST WEDNESDAY BUT TEMPS SHOULD FALL A
COUPLE DEGREES AS HEIGHTS BEGIN TO FALL AND THE RIDGE AXIS PUSHES
EAST. BREEZY CONDITIONS CAN BE EXPECTED IN THE AFTERNOON.
BY THURSDAY AND THROUGH THE REMAINDER OF THE WEEK, A SOUTHWESTERLY
FLOW WILL TAKE HOLD ACROSS THE MOJAVE DESERT AND GREAT BASIN AS THE
REGION IS SANDWICHED BETWEEN A RIDGE IN THE CENTRAL U.S AND A
TROUGH IN THE WEST. THIS WILL MAKE FOR BREEZY CONDITIONS AT TIMES
WITH SOME TRANSIENT CLOUD COVER. THERE IS A POSSIBILITY THAT SOME
MOISTURE FROM HURRICANE AMANDA WILL BE ADVECTED NORTH INTO THIS FLOW
AND BRING US A MORE MARKED INCREASE IN CLOUD COVER THURSDAY AND FRIDAY.
CHANCES FOR PRECIPITATION WITH THE REMNANT MOISTURE ARE PRETTY SLIM
BUT EASTERN PORTIONS OF THE FORECAST AREA, ESPECIALLY MOHAVE COUNTY,
WOULD BE THE BEST SUITED TO SEE SOME SHOWER ACTIVITY AS THE REMNANT
TROPICAL MOISTURE LIFTS NORTH.
FOR THE WEEKEND ONWARD...MODEL DIFFERENCES INCREASE WITH REGARD TO
HOW TO HANDLE THE CLOSED LOW IN THE WEST. FOR NOW KEPT THE FORECAST
DRY AND NEAR SEASONAL NORMALS FOR THE WEEKEND, WITH BREEZY
CONDITIONS CONTINUING.
&&
.AVIATION...FOR MCCARRAN...OTHER THAN AN ISOLATED SHOWER OVER THE
MOUNTAINS SURROUNDING THE VALLEY MOSTLY DRY CONDITIONS SHOULD
PERSIST THROUGH THE REMAINDER OF THE DAY. SOME SHOWERS WILL CONTINUE
TO THE NORTH AND EAST OF THE VALLEY INTO THIS EVENING. WINDS HAVE
SETTLED TO AN EASTERLY DIRECTION AS EXPECTED AN WILL LIKELY FLIRT
BETWEEN CONFIGS 2 AND 4 INTO THIS EVENING WITH SPEEDS OF 8-12
KTS. GUSTS INTO THE UPPER TEENS CANNOT BE RULED OUT. WINDS ARE
EXPECTED TO RETURN TO A SOUTHERLY DIRECTION BETWEEN 04-05Z. SKIES
WILL CLEAR OUT OVERNIGHT INTO SUNDAY MORNING AND LIGHT EASTERLY
WINDS WILL RETURN SUNDAY AFTERNOON.
FOR THE REST OF SOUTHERN NEVADA...SOUTHEAST CALIFORNIA...AND
NORTHWEST ARIZONA...LIGHT SHOWERS ASSOCIATED WITH A NORTH-SOUTH BAND
OF PRECIPITATION WILL CONTINUE ACROSS MOHAVE COUNTY INTO AT LEAST
THIS EVENING. NORTH OF LAS VEGAS SHOWERS AND ISOLATED THUNDERSTORMS
WILL BE POSSIBLE...WITH DRY CONDITIONS OVER THE REMAINDER OF THE
AREA. OUTSIDE OF SHOWER ACTIVITY...LIGHT WINDS SHOULD FAVOR TYPICAL
DIURNAL TRENDS THROUGH SUNDAY. MOSTLY DRY CONDITIONS WITH CLEARING
SKIES FOR SUNDAY WITH SHOWER ACTIVITY MAINLY LIMITED TO THE SIERRA.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
SHORT TERM/AVIATION...WOLCOTT
LONG TERM.............OUTLER
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
223 PM CDT SAT MAY 24 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 223 PM CDT SAT MAY 24 2014
THE MAIN FORECAST CHALLENGE WILL BE THE CONVECTIVE POTENTIAL OVER
WESTERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON AND EVENING...AND
DETERMINING IF IT WILL BE ONGOING OVER WESTERN NORTH DAKOTA
OVERNIGHT GIVEN THE PROXIMITY OF A SURFACE COLD FRONT.
FIRST THING`S FIRST...CONVECTION IS BEGINNING TO DEVELOP OVER
SOUTH CENTRAL NORTH DAKOTA...MAINLY OVER SIOUX AND GRANT COUNTIES.
THE LATEST HRRR CONTINUES TO PROG SCATTERED TO NUMEROUS
THUNDERSTORMS TO DEVELOP OVER SOUTH CENTRAL AND SOUTHWESTERN NORTH
DAKOTA WITHIN THE NEXT HOUR OR TWO...THEN SLOWLY MEANDER NORTH
LATE AFTERNOON. THIS IS IN AN AREA CHARACTERIZED BY MUCAPE BETWEEN
1500-2000 J/KG. HOWEVER...STORMS SHOULD HAVE A DIFFICULT TIME
ORGANIZING INTO ANYTHING MORE THAN MULTI-CELLULAR CLUSTERS AS DEEP
LAYER WIND SHEAR SHOULD REMAIN AT OR BELOW 20 KNOTS. GIVEN THE
SLOW STORM MOTIONS...THE MAIN THUNDERSTORM THREAT WILL BE LOCALLY
HEAVY RAIN WITH ISOLATED FLOODING POSSIBLE. ALSO...ISOLATED HAIL
AND LOCALLY HIGHER WINDS CANNOT BE RULED OUT.
LATE THIS EVENING AND OVERNIGHT...BOUNDARY LAYER CONDITIONS ARE
FORECAST TO STABILIZE WITH THE LOSS OF DAYTIME HEATING.
HOWEVER...THE SHORT RANGE MODELS MAINTAIN THUNDERSTORM CHANCES
OVERNIGHT AS A WEAK SHORTWAVE LIFTS NORTHEAST OVER THE STATE. FOR
NOW WILL KEEP THUNDERSTORM CHANCES IN THE FORECAST...WITH THE
CONVECTION EXPECTED TO REMAIN BELOW SEVERE LIMITS TONIGHT.
BY SUNDAY...A SURFACE COLD FRONT WILL ENTER WESTERN NORTH DAKOTA
IN THE MORNING...THEN SLOWLY PUSH INTO CENTRAL NORTH DAKOTA BY THE
AFTERNOON. THE FRONT SHOULD PROVIDE FOCUS FOR THUNDERSTORM
DEVELOPMENT THROUGH THE DAY. HOWEVER...THE GREATEST THUNDERSTORM
POTENTIAL APPEARS TO DEVELOP EAST OF HIGHWAY 83 SUNDAY AFTERNOON.
AGAIN...STORMS SHOULD HAVE A DIFFICULT TIME ORGANIZING INTO
ANYTHING MORE THAN MULTI-CELLULAR CLUSTERS AS DEEP LAYER WIND
SHEAR SHOULD REMAIN AT OR BELOW 20 KNOTS. GIVEN THE SLOW STORM
MOTIONS...THE MAIN THUNDERSTORM THREAT WILL AGAIN BE LOCALLY HEAVY
RAIN. ALSO...ISOLATED HAIL AND LOCALLY HIGHER WINDS CANNOT BE
RULED OUT.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 223 PM CDT SAT MAY 24 2014
A SERIES OF SHORTWAVES EMBEDDED AND ASSOCIATED SURFACE LOWS AND
FRONTAL PASSAGES WITHIN A WEAK SOUTHWEST FLOW WILL RESULT IN A
CONTINUED THREAT OF DAILY SHOWERS AND THUNDERSTORMS. RECENT TRENDS
IN THE 500MB HEIGHT FIELD SUGGEST A BRIEF REPRIEVE UNDER A
DEVELOPING RIDGE THURSDAY INTO FRIDAY MORNING ESPECIALLY OVER
CENTRAL NORTH DAKOTA. HOWEVER BASED ON THE LATEST AND PREVIOUS GFS
AND ECMWF FORECASTS...A RETURN TO YET ANOTHER POSSIBLE VERY WET
SCENARIO NEXT WEEKEND IS ADVERTISED. LITTLE RELIEF IN SITE BEYOND
THE LONG TERM PERIOD AS A SOUTHWEST FLOW IS FORECAST TO CONTINUE.
EXPECT A WARM WEEK WITH H85 TEMPS AROUND +20C OR IN THE LOWER 20C
RANGE. SOME SUNSHINE UNDER THIS SCENARIO WILL ALLOW FOR HIGHS IN THE
80S THROUGH FRIDAY...WITH SOME COOLING EXPECTED BY SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM CDT SAT MAY 24 2014
SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP LATER THIS
AFTERNOON...MAINLY IMPACTING KISN-KDIK-KBIS. IFR CONDITIONS ARE
POSSIBLE IN THUNDERSTORMS WITH SMALL HAIL AND LOCALLY STRONG
WINDS. ANOTHER ROUND OF SCATTERED THUNDERSTORMS WILL DEVELOP AFTER
MIDNIGHT AND WILL MOVE FROM WEST TO EAST THROUGH SUNDAY MORNING
ALONG A WEAK COLD FRONT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TM
LONG TERM...KS
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1244 PM CDT SAT MAY 24 2014
.UPDATE...
ISSUED AT 1244 PM CDT SAT MAY 24 2014
SENT OUT A QUICK UPDATE TO INCREASE WINDS OVER AREAS EAST OF
HIGHWAY 83 THIS AFTERNOON. GRADIENT FLOW HAS PICKED UP MORE THAN
THE MODELS HAVE PREVIOUSLY ANTICIPATED WITH A SURFACE LOW ENTERING
NORTHERN MANITOBA. OTHERWISE...SCATTERED TO NUMEROUS CONVECTION
DEVELOPING LATER THIS AFTERNOON STILL APPEARS TO BE VALID. THE
UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 1011 AM CDT SAT MAY 24 2014
AFTER NUMEROUS CALLS TO EMERGENCY MANAGEMENT AND IMPACTED
SPOTTERS IN THE AREAS AFFECTED BY THE HEAVY RAINFALL YESTERDAY
(NORTHERN BULEIGH...KIDDER...AND EASTERN STUTSMAN
COUNTIES)...DECIDED TO CANCEL THE AREAL FLOOD WARNING AND AREAL
FLOOD ADVISORIES SINCE THERE ARE NO LONGER ANY FLOODING IMPACTS. IT
IS WORTH NOTING THAT THESE AREAS WILL HAVE MUCH LOWER FLASH FLOOD
GUIDANCE FOR THIS AFTERNOON AND EVENING`S CONVECTION.
OTHERWISE...DID NOT DEVIATE FROM THE PREVIOUS FORECAST FOR THIS
UPDATE. THE CURRENT RUN OF THE HRRR SHOWS SCATTERED THUNDERSTORMS
DEVELOPING SOUTH CENTRAL AROUND 19Z...THEN SLOWLY BECOMING MORE
NUMEROUS OVER WESTERN AND CENTRAL NORTH DAKOTA LATER THIS
AFTERNOON. WEAK WIND FLOW SHOULD ALLOW FOR SLOW STORM MOTIONS ONCE
AGAIN...WITH HEAVY RAIN BEING THE PRIMARY THREAT. THE FRESHENED UP
PRODUCTS HAVE BE SENT.
UPDATE ISSUED AT 640 AM CDT SAT MAY 24 2014
UPDATE TO BLEND THE POPS FOR THE REMAINDER OF THE DAY AND TONIGHT
TO THE 06 UTC LARGER SCALE DETERMINISTIC SUITE AND THE HIGH
RESOLUTION 08-09 UTC RAP/HRRR RUNS. OTHERWISE THE FORECAST REMAINS
ON TRACK WITH CONVECTIVE HAZARDS UNCHANGED FROM THE PREVIOUS
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT SAT MAY 24 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS STORM
COVERAGE/INTENSITY AND POTENTIAL FOR LOCALLY HEAVY RAINFALL
THROUGH TONIGHT.
IN THE NEAR TERM...THUNDERSTORMS HAVE RAPIDLY DIMINISHED WITH ONLY
A FEW LINGERING SHOWERS EARLY THIS MORNING IN WELLS AND FOSTER
COUNTIES. STORM REDEVELOPMENT IS EXPECTED BY MIDDAY WITH STORMS
INCREASING IN COVERAGE BY LATE AFTERNOON AND EVENING. WESTERN AND
NORTH CENTRAL COUNTIES ARE OUTLOOKED IN THE SPC 5 PERCENT RISK
AREA FOR A FEW MARGINALLY SEVERE STORMS. AM EXPECTING A SIMILAR
SCENARIO TO FRIDAY NIGHT...WITH RELATIVELY SLOW STORM MOVEMENTS...DECENT
INSTABILITY...BUT WEAK DEEP LAYER SHEAR. THREATS INCLUDE ISOLATED
LARGE HAIL...AND PERHAPS A FEW STRONG WIND GUSTS GIVEN THE STEEP
LOW LEVEL LAPSE RATES THROUGH EARLY EVENING. IN ADDITION...WILL LIKELY
HAVE A FEW LOCATIONS WITH SUBSTANTIAL RAINFALL AMOUNTS...AND WILL
HAVE TO MONITOR THE AREAS HIT HARD BY RECENT RAIN...ESPECIALLY
EASTERN STUTSMAN COUNTY. HAVE INCLUDED A MENTION OF HEAVY RAIN IN
THE FORECAST GRIDS. AFTERNOON HIGHS SHOULD REACH THE 80S AGAIN
MOST LOCATIONS. THE THREAT FOR MARGINALLY SEVERE STORMS WILL
CONTINUE THROUGH SATURDAY EVENING...WITH POTENTIAL FOR ADDITIONAL
HEAVY RAIN PERSISTING THROUGH THE OVERNIGHT HOURS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 346 AM CDT SAT MAY 24 2014
AN ACTIVE WEATHER PATTERN WITH NEAR DAILY CHANCES FOR
THUNDERSTORMS...POSSIBLY SEVERE...WILL HIGHLIGHT THE EXTENDED
FORECAST.
THE 00 UTC GUIDANCE SUITE IS IN AGREEMENT ON A PROLONGED PERIOD
OF SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS UPSTREAM OF THE
CENTRAL CONUS UPPER LEVEL RIDGE AXIS. THIS SUPPORTS NEAR DAILY
CHANCES FOR CONVECTION ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
FOR SUNDAY A WEAK COLD FRONT/SURFACE TROUGH WILL PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. 1500-2000 J/KG OF ML CAPE IS
FORECAST ALONG AND AHEAD OF THE BOUNDARY ACROSS CENTRAL NORTH
DAKOTA WITH DEEP LAYER SHEAR OF 20-30 KTS...WHICH IS STRONGER THAN
THE AVAILABLE DEEP LAYER SHEAR ON FRIDAY AND SATURDAY. THUS...THE
THREAT FOR SEVERE HAIL AND WIND GUSTS WITH MORE ORGANIZED
CONVECTION IS HIGHER ON SUNDAY CENTRAL. CORFIDI VECTORS OF 10-15
KTS PROMOTES THE CONTINUED THREAT OF LOCALLY HEAVY RAIN WITH
THUNDERSTORMS WITH PWATS NEAR 1.25 INCHES. FOR MONDAY THROUGH
FRIDAY...HARD TO RULE OUT ANY SINGLE DAY WHERE AT LEAST A MARGINAL
THREAT FOR SEVERE WEATHER IS POSSIBLE GIVEN STRONGER UPPER LEVEL
FLOW UPSTREAM OF THE RIDGE AXIS AND GENERALLY SOUTHERLY LOW LEVEL
FLOW AHEAD OF LEE SURFACE TROUGHING TRANSPORTING SOUTHERN PLAINS
AND GULF OF MEXICO MOISTURE INTO THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM CDT SAT MAY 24 2014
SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP LATER THIS
AFTERNOON...MAINLY IMPACTING KISN-KDIK-KBIS. IFR CONDITIONS ARE
POSSIBLE IN THUNDERSTORMS WITH SMALL HAIL AND LOCALLY STRONG
WINDS. ANOTHER ROUND OF SCATTERED THUNDERSTORMS WILL DEVELOP AFTER
MIDNIGHT AND WILL MOVE FROM WEST TO EAST THROUGH SUNDAY MORNING
ALONG A WEAK COLD FRONT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...RPK
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1129 AM CDT SAT MAY 24 2014
.UPDATE...
THE MORNING MCV CONTINUES TO MOVE NORTHEAST AND SHOULD EXIT NORTH
TEXAS BY EARLY AFTERNOON. SOME WEAK SUBSIDENCE IN THE WAKE OF THIS
DISTURBANCE SHOULD KEEP NORTH TEXAS RAIN-FREE THROUGH ABOUT MID
AFTERNOON. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
STILL POSSIBLE LATE THIS AFTERNOON WITH THE BEST RAIN CHANCES ACROSS
THE WEST/NORTHWEST ZONES. SINCE MOST OF THE LARGE SCALE FORCING
WILL REMAIN OVER THE PANHANDLE...SOUTH PLAINS AND LOW ROLLING
PLAINS THROUGH THE EVENING...WE WILL KEEP ONLY 20 TO 30 POPS IN
THE FORECAST THROUGH TONIGHT.
NO MAJOR CHANGES ARE NEEDED WITH THIS UPDATE.
79
&&
.AVIATION...
OVERNIGHT GUIDANCE HAS DONE A POOR JOB OVER NORTH
TEXAS...DEVELOPING MORNING CONVECTION THAT IS NOT OCCURRING. I
THINK THAT THE MCV MOVING NORTHEAST INTO THE PARIS AREA HAS
PRODUCED AN AREA OF WEAK SUBSIDENCE BEHIND IT...AND MORNING
SOUNDING AT FWD SHOWED NO DEEP AREAS OF INSTABILITY TO PRODUCE
CONVECTION. I WILL THEREFORE REMOVE THE MORNING VCTS. WATER VAPOR
SHOWS A WEAK DISTURBANCE NEAR THE RIO GRANDE/BIG BEND THAT SHOULD
MOVE ACROSS NORTH TX LATER THIS AFTERNOON...WHICH WILL LIKELY
HELP PRODUCE SOME SHOWERS WHEN COMBINED WITH DAYTIME HEATING.
THERE MAY BE SOME EMBEDDED THUNDER IN IT AS WELL...SO WILL
REINTRODUCE VCTS INTO THE TAFS AT 21Z. CONFIDENCE IN
LOCATION/TIMING IS LOW GIVEN THE POOR GUIDANCE...AND THE FORECAST
IS BASED MOSTLY ON THE MORNING SOUNDING AND WATER VAPOR
IMAGERY...PLUS THE FACT THAT 12Z NAM AND 13Z RAP DO APPEAR DRIER
THAN THEIR PREVIOUS RUNS. 84
&&
.PREV DISCUSSION... /ISSUED 344 AM CDT SAT MAY 24 2014/
A MCV /MESOSCALE CONVECTIVE VORTEX/ THAT WAS LOCATED JUST
SOUTHEAST OF STEPHENVILLE AT 3 AM WILL CONTINUE TO MOVE EAST
NORTHEAST TODAY. THE BEST CHANCES OF SHOWERS AND THUNDERSTORMS
WILL REMAIN ACROSS WEST TEXAS BUT WITH THE MCV MOVING ACROSS THE
REGION AND ADDITIONAL ACTIVITY FROM WEST TEXAS POSSIBLY MOVING
INTO THE WEST LATE THIS AFTERNOON...HAVE LEFT 20 TO 30 PERCENT
POPS ACROSS NORTH AND CENTRAL TEXAS FOR TODAY.
OTHERWISE...THE MAIN UPPER LEVEL LOW THAT WAS OVER WESTERN
ARIZONA AT 3 AM /08Z/ WILL MOVE SLOWLY NORTHEAST ACROSS NEW
MEXICO/SOUTHERN COLORADO TONIGHT THROUGH SUNDAY NIGHT AND INTO
OKLAHOMA/KANSAS BY TUESDAY MORNING. THIS SYSTEM IS THEN EXPECTED
TO SLOWLY FILL AND SINK SOUTHEAST WEDNESDAY AND THURSDAY. THE
MODELS CONTINUE TO HAVE PROBLEMS WITH HOW TO HANDLE THIS SYSTEM
COMING UP WITH VARYING SOLUTIONS MID TO LATE WEEK. THE OPERATIONAL
GFS WEAKENS THIS SYSTEM SO MUCH THAT IT BECOMES DIFFUSE BY THE END
OF THE WORK WEEK. THE ECMWF ON THE OTHER HAND INDICATES THAT THE
LOW WILL DRIFT ACROSS SOUTHEASTERN OKLAHOMA WEDNESDAY NIGHT AND
THEN SINK SOUTH AND THEN SOUTH SOUTHWEST ACROSS NORTHEAST AND
NORTH CENTRAL TEXAS BY FRIDAY NIGHT. NEEDLESS TO SAY...CONFIDENCE
ON THE EVOLUTION OF THE UPPER SYSTEM REMAINS LOW.
THE AREAL COVERAGE OF SHOWERS AND THUNDERSTORMS WILL START TO
INCREASE ON MEMORIAL DAY AS LARGE SCALE LIFT INCREASES AHEAD OF
THE UPPER LEVEL TROUGH. PRECIPITABLE WATER VALUES WILL RISE ABOVE
1.5 INCHES. WE WILL SEE THE POTENTIAL FOR LOCALLY HEAVY RAIN
MONDAY THROUGH TUESDAY NIGHT. SOME STRONG TO SEVERE STORMS WILL
BE POSSIBLE MAINLY ACROSS THE WEST MONDAY AND AREA WIDE TUESDAY.
RAIN CHANCES WILL CONTINUE WEDNESDAY AND THURSDAY THOUGH THE
BETTER CHANCES WILL SHIFT EASTWARD. THE RAIN CHANCES FOR FRIDAY
AND SATURDAY WILL DEPEND ON WHAT HAPPENS WITH THE UPPER LEVEL
LOW/TROUGH. HAVE ADDED 20 TO 30 PERCENT POPS FOR FRIDAY AND
SATURDAY BASED ON ECMWF SOLUTION.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 86 68 88 70 85 / 30 20 20 20 30
WACO, TX 85 67 87 69 84 / 20 20 20 20 40
PARIS, TX 82 65 85 66 82 / 40 10 20 20 30
DENTON, TX 84 67 85 68 82 / 30 20 20 30 30
MCKINNEY, TX 83 66 85 69 83 / 30 20 20 20 30
DALLAS, TX 85 69 87 70 84 / 30 20 20 20 30
TERRELL, TX 86 68 87 69 85 / 20 10 20 20 30
CORSICANA, TX 84 67 87 68 84 / 20 10 20 20 30
TEMPLE, TX 85 66 86 67 83 / 20 20 20 20 40
MINERAL WELLS, TX 85 64 86 68 82 / 30 20 30 40 40
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
84/79
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
449 PM CDT SAT MAY 24 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 252 PM CDT SAT MAY 24 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE
CENTERED OVER LAKE MICHIGAN...BUT IT STRETCHES FROM THE GULF COAST
TO NORTHERN ONTARIO. WEAK SHORTWAVE ENERGY IS TRYING TO PLOW INTO
THE MID-LEVEL RIDGE AXIS POSITIONED OVER THE MISSISSIPPI VALLEY AND
IS SENDING AN ARCING AREA OF CIRRUS INTO WISCONSIN. OTHER MIDDLE
CLOUD COVER INCLUDING A FEW THUNDERSTORMS ARE WORKING ACROSS
MANITOBA AND ONTARIO WHERE DEEPER MOISTURE IS ROTATING AROUND THE
MID-LEVEL RIDGE. WITH HIGH PRESSURE LINGERING ACROSS THE
AREA...CLOUD COVER AND TEMPS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...SPRAWLING HIGH PRESSURE SYSTEM WILL SLIDE SOUTHEAST
TOWARDS THE CENTRAL APPALACHIANS. MODELS PROJECT THE 850-700MB
MOISTURE RETURN TO BYPASS THE REGION TO OUR NORTHWEST OVER THE
NORTHERN LAKE SUPERIOR. MID AND HIGH CLOUDS FROM ANY CONVECTION IN
THIS AREA COULD SPILL SOUTHWARD INTO NORTHERN WISCONSIN LATE THIS
EVENING INTO THE OVERNIGHT. THE OTHER AREA OF CIRRUS WILL ALSO PUSH
ACROSS MUCH OF NORTH-CENTRAL AND NORTHEAST WISCONSIN TONIGHT TOO.
SO INCREASED SKY COVER INTO THE PARTLY CLOUDY RANGE. BUT BY AND
LARGE...SHOULD SEE ANOTHER QUIET AND SEASONABLE NIGHT WITH LOWS IN
THE UPPER 40S TO LOWER 50S.
SUNDAY...RETURN FLOW AROUND THE NEARLY STATIONARY SURFACE HIGH WILL
BEGIN TO PUSH GREATER LOW LEVEL MOISTURE ACROSS CENTRAL AND WESTERN
WISCONSIN. STILL ANTICIPATE THAT A SIGNIFICANT DRY WEDGE WILL BE
PRESENT IN THE MID-LEVELS SINCE THE FORECAST AREA WILL BE LOCATED TO THE
EAST OF THE MID-LEVEL RIDGE AXIS. HIGHER PWATS WILL ALSO BE
ROTATING ACROSS LAKE SUPERIOR AROUND THE PERIPHERY OF THE RIDGE. SO
WILL CONTINUE TO SEE DRY CONDITIONS WITH TEMPS A COUPLE DEGREES
WARMER THAN TODAYS READINGS.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 252 PM CDT SAT MAY 24 2014
TIMING ISSUES WITH RESPECT TO A FEW FEATURES THIS WEEK WILL BE
THE PRIMARY ISSUE STARTING SUNDAY NIGHT.
PERSISTENT UPPER RIDGE OVER THE STATE BRINGING VERY PLEASANT
WEATHER TO THE REGION THIS WEEKEND IS PROGGED TO WEAKEN TO SOME
DEGREE AS A NEARLY CLOSED UPPER LOW SLOWLY WORKS TOWARD THE
REGION FROM THE SOUTHWEST STATES. ANOTHER PIECE OF ENERGY MOVING
OVER SOUTHERN CANADA WILL DECREASE HEIGHTS A TAD...BUT OVERALL
THE UPPER RIDGE IS PROGGED TO REMAIN THIS WEEK AND INTO THE START
OF NEXT WEEKEND. BUT PCPN CHANCES WILL BE PEPPERED OVER THE REGION
DUE TO SEVERAL SURFACE BOUNDARIES.
MODELS HAVE TRENDED WITH A SLOWER ARRIVAL TIME OF THE PCPN SUNDAY
NIGHT WITH THE SURFACE HIGH PRESSURE RIDGE HOLDING GROUND A BIT
LONGER. PROGS SUGGESTS THE PRIMARY SURFACE BOUNDARY WILL BE LOCATED
OVER THE NORTHERN PLAINS OR OVER MINNESOTA BY MONDAY MORNING. DID
NOT WANT TO GO COMPLETELY DRY LATER SUNDAY NIGHT OVER WESTERN
AREAS DUE TO WEAK WAA OVERNIGHT. IN GENERAL THE SURFACE FRONT IS
PROGGED TO SLOWLY DROP INTO CENTRAL WISCONSIN BY LATE AFTERNOON
MONDAY. SOME SURFACE CONVERGENCE AVAILABLE WITH THE FRONT BUT
WITH LITTLE SHEAR ALOFT...CONVECTION WILL LIKELY NEED TO BE AIDED
WITH AFTERNOON HEATING.
FORECAST CONTINUES TO BE MORE OF SUMMER TYPE WITH CONVECTION
FOCUSED ALONG A SUBTLE BOUNDARY SLOWLY DROPPING SOUTH OVER THE
AREA. AS THE PREVIOUS FORECAST SHIFT OBSERVED...A BLEND OF THE
MODEL RUNS SUGGESTS THE FRONT DOES NOT MOVE MUCH DUE TO THE
PERSISTENT UPPER RIDGE OVER THE AREA. THE LATEST 12Z ECMWF IS THE
OUTLIER WITH A DRIER FORECAST AND DRIVING THE FRONT FURTHER SOUTH
ON WEDNESDAY. ANTICIPATE A DRIER PERIOD LATER IN THE WEEK WITH
THE CANADIAN SURFACE HIGH PRESSURE SYSTEM NUDGING SOUTHWARD AND
THE UPPER HEIGHTS INCREASING AGAIN. NORTHERN STREAM ENERGY MAY
AGAIN ATTEMPT TO FLATTEN THE RIDGE FROM THE NORTH LATE IN THE WEEK
AND INTO NEXT WEEKEND. SO AGAIN A SIMILAR SITUATION DEVELOPING
WITH THE LOCATION AND TIMING OF THE FRONT NEAR THE END OF THE NEW
WORK WEEK. GFS IS LOOKING MUCH DRIER FOR FRIDAY AND PERHAPS
EVEN INTO SATURDAY FOR MOST OF CENTRAL WISCONSIN AS A BACK DOOR
COOL FRONT SLIDES SOUTH OVER MUCH OF THE STATE.
TOTAL TOTALS CLIMB TO THE MID OR UPPER 40S MONDAY AND DO NOT
EXCEED THOSE NUMBERS THROUGH WEDNESDAY. BEST CAPE NUMBERS ALSO
FOCUSED FOR THE AFTERNOON AND EVENING HOURS FOR MOST LIKELY
PERIODS OF CONVECTION. PWATS CLIMB TO TO 1.5 INCHES AND WITH SLOW
STORM MOVEMENT UNDER THE RIDGE...ANY CONVECTION WHICH CAN DEVELOP
COULD PRODUCE SOME HEALTHY LOCALIZED RAINFALL.
WILL ADD SOME FOG TO THE NEARSHORE AREAS MONDAY THROUGH WEDNESDAY
DUE TO LIGHT WINDS NEAR THE FRONT AND SURFACE DEWPOINTS CLIMBING
TO AROUND 60.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 447 PM CDT SAT MAY 24 2014
QUIET WX WITH VFR CONDITIONS EXPECTED THE NEXT 24 HRS AS SFC HIGH
LINGERS ACRS THE AREA. HIGH WL BEGIN TO EDGE E BY LATE TOMORROW...
ALLOWING INCRG CLDS AND EVENTUALLY A CHC OF SHRA BY LATE SUN
NGT/MON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......SKOWRONSKI
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 252 PM CDT SAT MAY 24 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE
CENTERED OVER LAKE MICHIGAN...BUT IT STRETCHES FROM THE GULF COAST
TO NORTHERN ONTARIO. WEAK SHORTWAVE ENERGY IS TRYING TO PLOW INTO
THE MID-LEVEL RIDGE AXIS POSITIONED OVER THE MISSISSIPPI VALLEY AND
IS SENDING AN ARCING AREA OF CIRRUS INTO WISCONSIN. OTHER MIDDLE
CLOUD COVER INCLUDING A FEW THUNDERSTORMS ARE WORKING ACROSS
MANITOBA AND ONTARIO WHERE DEEPER MOISTURE IS ROTATING AROUND THE
MID-LEVEL RIDGE. WITH HIGH PRESSURE LINGERING ACROSS THE
AREA...CLOUD COVER AND TEMPS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...SPRAWLING HIGH PRESSURE SYSTEM WILL SLIDE SOUTHEAST
TOWARDS THE CENTRAL APPALACHIANS. MODELS PROJECT THE 850-700MB
MOISTURE RETURN TO BYPASS THE REGION TO OUR NORTHWEST OVER THE
NORTHERN LAKE SUPERIOR. MID AND HIGH CLOUDS FROM ANY CONVECTION IN
THIS AREA COULD SPILL SOUTHWARD INTO NORTHERN WISCONSIN LATE THIS
EVENING INTO THE OVERNIGHT. THE OTHER AREA OF CIRRUS WILL ALSO PUSH
ACROSS MUCH OF NORTH-CENTRAL AND NORTHEAST WISCONSIN TONIGHT TOO.
SO INCREASED SKY COVER INTO THE PARTLY CLOUDY RANGE. BUT BY AND
LARGE...SHOULD SEE ANOTHER QUIET AND SEASONABLE NIGHT WITH LOWS IN
THE UPPER 40S TO LOWER 50S.
SUNDAY...RETURN FLOW AROUND THE NEARLY STATIONARY SURFACE HIGH WILL
BEGIN TO PUSH GREATER LOW LEVEL MOISTURE ACROSS CENTRAL AND WESTERN
WISCONSIN. STILL ANTICIPATE THAT A SIGNIFICANT DRY WEDGE WILL BE
PRESENT IN THE MID-LEVELS SINCE THE FORECAST AREA WILL BE LOCATED TO THE
EAST OF THE MID-LEVEL RIDGE AXIS. HIGHER PWATS WILL ALSO BE
ROTATING ACROSS LAKE SUPERIOR AROUND THE PERIPHERY OF THE RIDGE. SO
WILL CONTINUE TO SEE DRY CONDITIONS WITH TEMPS A COUPLE DEGREES
WARMER THAN TODAYS READINGS.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 252 PM CDT SAT MAY 24 2014
TIMING ISSUES WITH RESPECT TO A FEW FEATURES THIS WEEK WILL BE
THE PRIMARY ISSUE STARTING SUNDAY NIGHT.
PERSISTENT UPPER RIDGE OVER THE STATE BRINGING VERY PLEASANT
WEATHER TO THE REGION THIS WEEKEND IS PROGGED TO WEAKEN TO SOME
DEGREE AS A NEARLY CLOSED UPPER LOW SLOWLY WORKS TOWARD THE
REGION FROM THE SOUTHWEST STATES. ANOTHER PIECE OF ENERGY MOVING
OVER SOUTHERN CANADA WILL DECREASE HEIGHTS A TAD...BUT OVERALL
THE UPPER RIDGE IS PROGGED TO REMAIN THIS WEEK AND INTO THE START
OF NEXT WEEKEND. BUT PCPN CHANCES WILL BE PEPPERED OVER THE REGION
DUE TO SEVERAL SURFACE BOUNDARIES.
MODELS HAVE TRENDED WITH A SLOWER ARRIVAL TIME OF THE PCPN SUNDAY
NIGHT WITH THE SURFACE HIGH PRESSURE RIDGE HOLDING GROUND A BIT
LONGER. PROGS SUGGESTS THE PRIMARY SURFACE BOUNDARY WILL BE LOCATED
OVER THE NORTHERN PLAINS OR OVER MINNESOTA BY MONDAY MORNING. DID
NOT WANT TO GO COMPLETELY DRY LATER SUNDAY NIGHT OVER WESTERN
AREAS DUE TO WEAK WAA OVERNIGHT. IN GENERAL THE SURFACE FRONT IS
PROGGED TO SLOWLY DROP INTO CENTRAL WISCONSIN BY LATE AFTERNOON
MONDAY. SOME SURFACE CONVERGENCE AVAILABLE WITH THE FRONT BUT
WITH LITTLE SHEAR ALOFT...CONVECTION WILL LIKELY NEED TO BE AIDED
WITH AFTERNOON HEATING.
FORECAST CONTINUES TO BE MORE OF SUMMER TYPE WITH CONVECTION
FOCUSED ALONG A SUBTLE BOUNDARY SLOWLY DROPPING SOUTH OVER THE
AREA. AS THE PREVIOUS FORECAST SHIFT OBSERVED...A BLEND OF THE
MODEL RUNS SUGGESTS THE FRONT DOES NOT MOVE MUCH DUE TO THE
PERSISTENT UPPER RIDGE OVER THE AREA. THE LATEST 12Z ECMWF IS THE
OUTLIER WITH A DRIER FORECAST AND DRIVING THE FRONT FURTHER SOUTH
ON WEDNESDAY. ANTICIPATE A DRIER PERIOD LATER IN THE WEEK WITH
THE CANADIAN SURFACE HIGH PRESSURE SYSTEM NUDGING SOUTHWARD AND
THE UPPER HEIGHTS INCREASING AGAIN. NORTHERN STREAM ENERGY MAY
AGAIN ATTEMPT TO FLATTEN THE RIDGE FROM THE NORTH LATE IN THE WEEK
AND INTO NEXT WEEKEND. SO AGAIN A SIMILAR SITUATION DEVELOPING
WITH THE LOCATION AND TIMING OF THE FRONT NEAR THE END OF THE NEW
WORK WEEK. GFS IS LOOKING MUCH DRIER FOR FRIDAY AND PERHAPS
EVEN INTO SATURDAY FOR MOST OF CENTRAL WISCONSIN AS A BACK DOOR
COOL FRONT SLIDES SOUTH OVER MUCH OF THE STATE.
TOTAL TOTALS CLIMB TO THE MID OR UPPER 40S MONDAY AND DO NOT
EXCEED THOSE NUMBERS THROUGH WEDNESDAY. BEST CAPE NUMBERS ALSO
FOCUSED FOR THE AFTERNOON AND EVENING HOURS FOR MOST LIKELY
PERIODS OF CONVECTION. PWATS CLIMB TO TO 1.5 INCHES AND WITH SLOW
STORM MOVEMENT UNDER THE RIDGE...ANY CONVECTION WHICH CAN DEVELOP
COULD PRODUCE SOME HEALTHY LOCALIZED RAINFALL.
WILL ADD SOME FOG TO THE NEARSHORE AREAS MONDAY THROUGH WEDNESDAY
DUE TO LIGHT WINDS NEAR THE FRONT AND SURFACE DEWPOINTS CLIMBING
TO AROUND 60.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1232 PM CDT SAT MAY 24 2014
GOOD FLYING WEATHER WILL BE PRESENT ACROSS THE REGION THROUGH THE
END OF THE TAF PERIOD THANKS TO A SLOW MOVING HIGH PRESSURE SYSTEM.
SCT MIDDLE AND HIGH CLOUDS WILL ARRIVE LATER THIS AFTERNOON...BUT
CONDITIONS TO REMAIN VFR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
243 PM MDT SAT MAY 24 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 245 PM MDT SAT MAY 24 2014
FORECAST CHALLENGES DEAL WITH PRECIP LOCATIONS AND TIMING THROUGH
MONDAY MORNING.
CURRENTLY...LATEST WATER VAPOR IMAGERY SHOWING LOW JUST SOUTH OF
THE 4 CORNERS AREA EARLY THIS AFTERNOON. WIDESPREAD CONVECTION IN
THE TEXAS PANHANDLE IS A BIT CONCERNING AS CIRRUS BLOWOFF IS
MAKING ITS WAY UP INTO THE SOUTHERN PANHANDLE AND ALONG THE FRONT
RANGE THIS AFTERNOON. OUT WEST...CONVECTION IS BEGINNING TO
BLOSSOM OVER CONVERSE COUNTY AND OVER THE SNOWY RANGE. EVEN
BEGINNING TO SEE SOME LIGHTNING STRIKES IN CONVECTION UNDER THE
CIRRUS BLOWOFF EAST OF THE LARAMIE RANGE. CONVECTION IS BECOMING
MORE WIDESPREAD OVER WESTERN COLORADO. STORM MOTIONS ARE
SLOW...WITH A NORTH TO NORTHEAST DRIFT.
FORECAST FOR TONIGHT SHOWING ANOTHER PIECE OF ENERGY MOVING NORTH
OUT OF COLORADO. SOME DIFFERENCES IN MODEL SOLUTIONS ON QPF
PLACEMENT. GFS KEEPS HIGHEST QPF JUST SOUTH OF THE SNOWY AND
SIERRA MADRE RANGES TONIGHT. ECMWF HITTING THE SOUTH LARAMIE RANGE
OVER TO THE SNOWY RANGE...WHILE THE NAM IS HITTING THE SNOWY RANGE
PRETTY GOOD. DID A BLEND OF THE MODELS ON QPF HITTING THE
MOUNTAINS PRETTY HARD WITH A QUARTER TO A HALF INCH TONIGHT. WITH
THE SLOW MOVEMENT OF THESE STORMS...WE COULD SEE HIGHER AMOUNTS IN
STALLED OUT THUNDERSTORMS. BY 12Z SUNDAY...PWATS OUT BY RAWLINS
ARE UP TO 3/4THS OF AN INCH. WHERE EVER THESE STORMS
DEVELOP...FOLKS UNDERNEATH THEM ARE GOING TO SEE A LOT OF RAIN.
ONE LAST ITEM OF CONCERN...LATEST HRRR FORECAST HAS CONVECTION
FURTHER EAST...MORE ACROSS THE SOUTH LARAMIE RANGE AND MOST OF
LARAMIE COUNTY. SHOULD THIS SOLUTION COME TRUE...THE EVENING SHIFT
MAY NEED TO BE WATCHING FOR FLASH FLOOD POTENTIAL HERE. WILL LEAVE
CURRENT WATCHES AS THEY ARE THOUGH...GIVEN THE WIDE VARIETY OF
SOLUTIONS.
PRECIP WIDESPREAD SUNDAY. ECMWF HAS UPPER LOW CENTERED OVER
SOUTH/CENTRAL COLORADO. VORTICITY LOBE ROTATING AROUND THE NORTH
SIDE OF THIS LOW INTO SOUTH/CENTRAL WYOMING. ECMWF BY FAR THE MOST
BULLISH ON QPF...WITH WIDESPREAD HALF INCH OF RAIN OVER MOST OF THE
CWFA. ALL THREE MODELS ARE HITTING THE SNOWY/SIERRA MADRE RANGES
TOMORROW AFTERNOON. CONFIDENCE IS INCREASING SIGNIFICANTLY BASED
ON THIS TREND FOR A MAJOR RAIN ON SNOW EVENT OUT THERE. WILL
UPDATE THE HWO TO HIT THE WESTERN HALF OF THE CWFA SUNDAY. LATEST
NAM SOUNDINGS SHOWING A LONG/SKINNY CAPE PROFILE FOR CARBON COUNTY
WITH SBCAPES AROUND 500J/KG. WILL BE DEALING WITH SIGNIFICANT
FLOOD/FLASH FLOOD PROBLEMS OUT THERE TOMORROW.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 242 PM MDT SAT MAY 24 2014
AFTER A POTENTIALLY ACTIVE SUNDAY AND MONDAY FOR INCREASED FLASH
FLOOD THREAT IN SOME AREAS OF OUR WESTERN ZONES...THE MIDWEEK
TIME FRAME LOOKS TO BE MUCH LESS ACTIVE CONVECTION-WISE WITH
GFS/ECMWF SHOWING A DEEPLY SUBSIDENT AIR MASS ACROSS MUCH OF THE
FORECAST AREA TUESDAY INTO WEDNESDAY. A LOW TO MIDLEVEL DRYSLOT
WORKS GRADUALLY EASTWARD ACROSS THE FORECAST AREA TUESDAY AND
WEDNESDAY UNDERNEATH THE RIDGE ZONE BETWEEN THE UPPER LOW OVER
TEXAS AND THE NEXT LOW SWINGING DOWN THE PACIFIC NORTHWEST. WE
WILL CARRY SOME SMALL POPS IN THE MOUNTAINS OUT WEST FOR THE
POTENTIAL OF ISOLATED CONVECTION IN THE AFTENOONS...BUT OVERALL
MOST SPOTS SHOULD REMAIN DRY AND FAIRLY WARM IN THE MIDWEEK
TIMEFRAME. SUBSIDENT AIRMASS TUESDAY INTO WEDNESDAY WITH 700 MB
TEMPS AT +14C OVER THE WESTERN ZONES COULD RESULT IN AN INCREASED
SNOWMELT IN THE HIGHER ELEVATIONS MIDWEEK AS WELL (SOMETHING THAT
WE WILL DEFINITELY NEED TO WATCH). BY LATE NEXT WEEK...WITH SOME
INTEREST WE NOW NOTE HOW THE 12Z GFS AND THE 12Z ECMWF DRAW
PACIFIC MOISTURE UP INTO OUR REGION ON FRIDAY FROM WHAT WOULD
POSSIBLY BE LEFTOVER OF A SHEARED-OUT TROPICAL CYCLONE AMANDA. IT
IS WAY TOO EARLY IN THE FORECAST PROCESS NOW TO SAY WITH ANY
CONFIDENCE AS TO WHETHER OR NOT THIS COULD RESULT IN ANOTHER HEAVY
RAIN THREAT FOR OUR REGION BY NEXT WEEKEND...BUT THIS IS SOMETHING
FOR US TO KEEP AN EYE ON. FOR NOW WE HAVE CONTINUED PREVIOUS
FORECAST TREND OF INCREASING POPS GOING INTO NEXT WEEKEND. STAY
TUNED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 1152 AM MDT SAT MAY 24 2014
CONVECTION/STORMS STARTING TO INITIATE OVER PORTIONS OF CARBON AND
CONVERSE COUNTIES IN WYOMING SHORTLY BEFORE NOON...AND WE EXPECT
TO SEE SCATTERED THUNDERSTORMS BECOMING A MORE NUMEROUS AROUND SE
WYOMING AND THE WESTERN NEBRASKA PANHANDLE BETWEEN 2 PM AND 8 PM.
MESOSCALE MODELS GENERALLY AGREE THAT THE SOMEWHAT GREATER
COVERAGE OF STORMS WILL LIKELY BE WEST OF I-25 TODAY WHERE THE
WHERE BREAKS IN THE MID/HIGH LEVEL CLOUD COVER HAVE BEEN QUICKER TO
OCCUR AND CONVECTION IS ALREADY GETTING AN EARLY START. CARRIED
VCNTY MENTION OF THUNDERSTORMS 2 PM-9 PM AT ALL SITES BUT MAY BE
ABLE TO PIN IT DOWN WITH PREVAILING THUNDERSTORM PERIODS A LITTLE
BETTER NEXT COUPLE OF HOURS AT THE WESTERN AIRPORTS WHEN WE SEE
HOW THE CONVECTIVE PATTERN WILL ACTUALLY UNFOLD. OTHERWISE...OTHER
MAIN CONCERN TONIGHT WILL BE THE RE-FORMATION OF LOW CLOUDS AND
FOG OUT EAST ON THE PLAINS. MODELS WANT TO BRING CEILINGS AND
VISIBILITIES DOWN AT OR BELOW IFR CATEGORY AT ALLIANCE AND SIDNEY
AGAIN TONIGHT...AND GIVEN THE PATTERN OF LIGHT TO MODERATE
SOUTHEASTERLY BOUNDARY LAYER FLOW TONIGHT SEE NO REASON TO ARGUE
WITH IT. MENTIONED MVFR VISIBILITY/CEILING AT CHADRON...
SCOTTSBLUFF AND CHEYENNE WITH OTHER SITE OVERNIGHT VFR.
&&
.FIRE WEATHER...
ISSUED AT 242 PM MDT SAT MAY 24 2014
FIRE CONCERNS WILL BE MINIMAL THROUGH THE HOLIDAY WEEKEND AS A MOIST
AIR MASS COMBINES WITH FUELS THAT ARE IN GREEN-UP. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED ALONG AND EAST
OF THE LARAMIE RANGE MOST DAYS...WITH VERY GOOD CHANCES FOR WETTING
RAINS. A MORE WIDESPREAD RAIN EVENT SUNDAY WILL CONTINUE TO
SUPPRESS FIRE WEATHER CONCERNS FOR THE DISTRICT. WARMER AND DRIER
WEATHER IS ANTICIPATED TO RETURN MON-WED. FORTUNATELY WINDS WILL
BE RELATIVE LIGHT THRU THIS PERIOD. THUNDERSTORM CHANCES RETURN IN
EARNEST LATE NEXT WEEK.
&&
.HYDROLOGY...
ISSUED AT 242 PM MDT SAT MAY 24 2014
CONTINUING SNOWMELT WILL COMBINE WITH AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS TO CREATE CONTINUED RIVER RISES ON THE UPPER NORTH
PLATTE RIVER TODAY THROUGH MOST OF THE UPCOMING WEEK. MODERATE RAIN
IS STILL POSSIBLE SUNDAY WHICH COULD ADD TO FURTHER RAPID RISES.
FLOOD AND FLASH FLOOD WATCHES CONTINUE FOR MUCH OF CARBON COUNTY FOR
SUNDAY AS A RESULT. MUCH WARMER TEMPERATURES ARE BECOMING LIKELY NEXT
WEEK WHICH WILL INCREASE SNOWMELT EVEN MORE. A FLASH FLOOD WATCH
REMAINS IN EFFECT FOR THE SNOWY...SIERRA MADRE...AND NORTHERN
LARAMIE RANGES THROUGH THE WEEKEND. LOCALIZED FLASH FLOODING IS
ALSO POSSIBLE OVER THE HIGH PLAINS OF SOUTHEAST WY AND THE WESTERN
NE PANHANDLE...BUT ACTIVITY WILL BE MORE ISOLATED IN NATURE.
PLEASE SEE FFACYS FOR PUBLIC INFORMATION REGARDING CURRENT
HYDROLOGIC CONCERNS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR WYZ103-112-114.
FLOOD WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON FOR
WYZ105-109-110-113-115.
NE...NONE.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...GARMON
AVIATION...GARMON
FIRE WEATHER...CLAYCOMB
HYDROLOGY...CLAYCOMB