Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/24/12
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
927 PM MDT WED MAY 23 2012
.UPDATE...
ISSUED AT 926 PM MDT WED MAY 23 2012
THE COLD FRONT IS SWEEPING SOUTH ACROSS SE UTAH/SW COLORADO. AT
03Z THIS EVENING...THE COLD FRONT IS PASSING THE DURANGO AIRPORT.
WHILE WINDS ARE EXPECTED TO SUBSIDE IN THE POST FRONTAL AIR
MASS...WINDS STILL FAIRLY STRONG AND ELECTED TO EXTEND THE RED
FLAG WARNING AND WIND ADVISORY THROUGH 11 PM.
THE VAIL PASS WEB CAM SHOWED LIGHT SNOW ACCUMULATION ON THE GRASSY
AND DIRT SURFACES. HIGH MOUNTAIN REMOTE SENSORS INDICATE THAT
TEMPERATURES ARE AROUND 32F AND INDICATE THAT SNOW ACCUMULATIONS
WILL BE FAIRLY COMMON ABOVE 10K FEET. THE BRUNT OF THE
PRECIPITATION OCCURS BEFORE MIDNIGHT WITH THE HRRR SHOWING FAST
DROP OFF IN QPF AMOUNTS AFTER 06Z. ELECTED TO ISSUE SPECIAL
WEATHER STATEMENT TO ADDRESS THE IMPACT OF LATE SEASON SNOWFALL
INSTEAD OF HOIST A WINTER WEATHER ADVISORY. WIDESPREAD SNOW ABOVE
10K FEET IS EXPECTED TO TAPER OFF WITHIN THE NEXT 2-3 HOURS (AND
PAVEMENTS MAY STAY WET WITH SLUSHY AREAS).
UPDATE ISSUED AT 723 PM MDT WED MAY 23 2012
AS THE NOSE OF JET PUNCHES INTO WRN COLORADO...PRECIPITATION HAS
INCREASED ACROSS PARTS OF NORTHWEST AND WEST CENTRAL COLORADO.
RAISED POPS TO ACCOUNT FOR THIS INCREASE...ALTHOUGH TRACE AMOUNTS
MAY BE THE ONLY RAINFALL THE LOWER VALLEYS RECEIVE AS THE EVENING
SOUNDING SHOWS A MOSTLY DRY SUB CLOUD LAYER. HOWERVER PRECIPITABLE
WATER DID RISE TO ONE HALF INCH. THESE SHOWERS HAVE ENHANCED GUSTY
WINDS IN THE CENTRAL VALLEY WITH LOCAL GUSTS TO 40 MPH. FARTHER
SOUTH...GUSTY WINDS HAVE BEEN STRONGER WITH GUSTS OF 45 TO 50 MPH
FAIRLY COMMON. NO UPDATES TO THE WIND ADVISORY THAT EXPIRES AT
9 PM MDT THIS EVENING.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM MDT WED MAY 23 2012
LARGE SCALE ASCENT IS INCREASING OVER NORTHERN UTAH INTO NORTHWEST
COLORADO AHEAD OF THE MID LEVEL TROF AXIS DROPPING THROUGH THE
GREAT BASIN. DARKENING IN THE WATER VAPOR IMAGERY SHOWING THIS
LIFT BEING ENHANCED BY ARRIVING JET MAX AND ASSOCIATED PV LOBE
WITH INCREASING INSTABILITY FROM DAYTIME HEATING AND COOLER AIR
MOVING IN WITH THE TROF ALSO AIDING ASCENT. 88D MOSAIC IS
RESPONDING BY SHOWING AN INCREASE IN COVERAGE MAINLY NORTH OF A
MOAB TO MONTROSE TO GUNNISON LINE WHICH IS NEAR WHERE THE SURFACE
FRONT HAS SETTLED AND MAY BE WAVERING. THIS LIFT SEEMS TO BE
HELPING TO MIX OUT THE ATMOSPHERE NORTH OF FRONT AS WELL WITH
WINDS PICKING UP AT GJT THE PAST HOUR OR SO. SOME GUIDANCE
INDICATING VERY GUSTY WINDS THROUGH EARLY EVENING ACROSS THE GRAND
VALLEY AND WILL CONTINUE TO MONITOR. FARTHER SOUTH IN ADVISORY
REGION STRONG MIXING AHEAD OF THE FRONT HAS BEEN PUSHING WIND
GUSTS NEAR 45 MPH AND EXPECT THE NEXT FEW HOURS THEY COULD
CONTINUE TO STRENGTHEN SO WILL LEAVE ADVISORY AS IS. AS FOR
PRECIPITATION THE BEST FOCUS CONTINUES TO POINT AT THE NORTHERN
AND CENTRAL MOUNTAINS THROUGH THIS EVENING WHERE MID LEVEL LAPSE
RATES WILL CONTINUE TO STEEPEN UNDER THE STRONGER DYNAMICS ALOFT.
MOISTURE IS ALREADY IN PLACE NORTH OF THE FRONT SO SHOULD NOT TAKE
MUCH TO GET PRECIPITATION TO THE SURFACE. ONE CAVEAT HOWEVER IS DRIER
AIR IS ADVECTING IN A LOW LEVELS FROM WYOMING SO WILL KEEP THE
HIGHEST POPS ON THE TERRAIN WHERE OROGRAPHICS WILL ALSO CONTINUE
INTO THE THURSDAY MORNING AS THE UPPER SUPPORT LIFTS OUT OF OUR
REGION. WOULD NOT BE SURPRISED TO SEE SOME LIGHT SNOW ABOVE THE
9000 FT LEVEL BUT SHOULD NOT ANTICIPATING A LARGE IMPACT ATTM WITH
AN INCH OR LESS LIMITED TO THE VEGETATION. THE SURFACE FRONT WILL
BE SAGGING THROUGH THE SOUTHERN CWA TONIGHT AS WELL AND THIS MAY
HELP TRIGGER SOME ISOLATED CONVECTION IN THE SOUTHERN
MOUNTAINS...BUT CONFIDENCE NOT HIGH SO POPS REFLECT THIS.
TEMPERATURES WILL BE QUITE COOL COMPARED TO THE PAST FEW NIGHTS
WITH SOME VALLEYS IN THE NORTH DROPPING TO NEAR THE FREEZING MARK.
WITH THE FRONT NEAR THE SOUTHERN BORDER ON THURSDAY AND COOLER DAY
LOOKS ON TRACK AND THERE SHOULD BE A FAIR AMOUNT OF SUNSHINE IN
PLACE BEFORE AFTERNOON HEATING STARTS POPPING THE CUMULUS. THE
EXCEPTION WILL BE OVER THE FAR NORTHERN MOUNTAINS EARLY DUE TO THE
MOIST DENDRITIC FLOW AND COLD POOL ALOFT WHICH SHOULD PRODUCE SOME
LIGHT PRECIPITATION. HIGHS ACTUALLY LOOK TO BE RUN NEAR OR BELOW
NORMAL OUTSIDE THE 4 CORNERS REGION AND DID USE A BLEND OF GUIDANCE.
A STRONGER WESTERN SYSTEM WILL BE PUSHING INTO THE EASTERN GREAT
BASIN TOMORROW NIGHT. THIS WILL QUICKLY BACK AND INCREASE THE FLOW
TO THE SOUTHWEST AND PUSH THE WARM FRONT STRUCTURE BACK NORTHWARD
THROUGH THE CWA. ATTM THE MODELS ARE PUTTING OUT SOME LIGHT
PRECIPITATION BUT MODEL SOUNDINGS WOULD INDICATE THIS IS MOSTLY IN
THE FORM OF ACCAS MOVING OVERHEAD IN THE STRONG WAA PATTERN. FOR NOW
JUST PUT IN SOME ISOLATED MENTION OVER THE HIGHEST TERRAIN IN THE
NORTHEAST CWA. BETTER MIXING AND THE WAA SHOULD PUSH LOWS UP A FEW
DEGREES OVER TONIGHT/S READINGS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM MDT WED MAY 23 2012
MODELS REMAIN CONSISTENT ON DROPPING THE NEXT PACIFIC TROUGH INTO
THE WESTERN GREAT BASIN FRIDAY AND THEN LIFTING IT OUT TO THE
NORTHEAST THIS WEEKEND...DRAGGING A COLD FRONT ACROSS SAT OR SAT
EVENING. NOT A LOT OF MOISTURE INDICATED WITH THIS FRONT...SO JUST
SLIGHT CHANCE TO CHANCE POPS FOR MAINLY NE UT AND NW CO SHOULD
SUFFICE FOR NOW. ABOVE NORMAL TEMPS FOR FRIDAY AS WARM ADVECTION
RETURNS. WITH THE MAIN UPPER LOW LIFTING OUT WELL TO OUR NW...MAY
SEE THE EASTWARD PROGRESSION OF THE COLD FRONT SLOW ON SATURDAY SO
WILL KEEP MAX TEMPS ON THE WARM SIDE SAT OVER ALL BUT NE UT.
THE BIGGEST IMPACT WILL LIKELY BE THE SOUTH TO SOUTHWEST WIND...
WHICH IS EXPECTED TO STRENGTHEN SIGNIFICANTLY FRIDAY THROUGH
SATURDAY. BOTH NAM AND GFS SHOW 40-45 KTS AT 700 MB...WITH SOME
AREAS OF 50-55 KTS WINDS INDICATED FRI NIGHT. WIND ADVISORIES MAY BE
NEEDED...AND A FIRE WEATHER WATCH HAS ALREADY BEEN ISSUED FOR FRI
AND SAT.
COOLER TEMPERATURES FOLLOW FOR SUNDAY BEHIND THE FRONT WITH A CHANCE
OF SHOWERS PERSISTING FOR THE NORTHERN MTNS IN THE WEST TO NW FLOW.
DRY WESTERLY FLOW EXPECTED MONDAY THROUGH WEDNESDAY WITH
TEMPERATURES WARMING UP AGAIN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 345 PM MDT WED MAY 23 2012
SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO INCREASE OVER THE
NEXT FEW HOURS ACROSS THE NORTHERN AND CENTRAL MOUNTAINS OF
COLORADO. CONFIDENCE NOT HIGH ENOUGH TO PLACE RESTRICTIONS IN
PREVAILING FORECASTS OVER THE HIGH VALLEY TERMINALS SUCH AS EGE
AND ASE...BUT PASSING SHOWERS CAN BE ANTICIPATED. COLD FRONTAL
PASSAGE HAS LIMITED MIXING THE VALLEYS AS WELL AND UP VALLEY WINDS
HAVE BEEN SLOW TO DEVELOP BUT THE SHOWERS MAY HELP ENHANCE THIS
AND STILL EXPECT SOME GUSTY WINDS. WINDS WILL BE STRONG FROM THE
GRAND VALLEY INTO SOUTHWEST COLORADO AFFECTING LIGHT AIRCRAFT
OPERATIONS OVER THESE AIRPORTS...WHILE CREATING MECHANICAL
TURBULENCE OVER MANY RIDGE TOPS. MOUNTAIN OBSCURATIONS CAN ALSO BE
EXPECTED OVER THE NORTHERN AND CENTRAL MOUNTAINS THROUGH THURSDAY
MORNING BEFORE DRIER AIR WORKS IN AND LIFT MOVES INTO THE PLAINS.
VFR CONDITIONS CAN BE EXPECTED OVER THE LOWER VALLEY TERMINALS
OVER THE NEXT 24 HOURS.
&&
.FIRE WEATHER...
ISSUED AT 345 PM MDT WED MAY 23 2012
RED FLAG WARNING CONTINUES FOR SOUTHWEST AND PORTIONS OF
WEST-CENTRAL CO THROUGH THIS EVENING.
THURSDAY LOOKS LIKE A BIT OF DOWN DAY WITH SLIGHTLY WEAKER WINDS
ALOFT AND AT THE SURFACE...THOUGH LOCALIZED BORDERLINE CRITICAL
CONDITIONS WILL BE POSSIBLE IN SOUTHWEST CO.
WINDY AND DRY CONDITIONS LOOK IN STORE FOR FRIDAY AND SATURDAY AS
THE NEXT STORM DROPS INTO THE GREAT BASIN. THE FIRE WEATHER WATCH
CURRENTLY STARTING FRIDAY AFTERNOON HAS NOW BEEN EXTENDED UNTIL
SATURDAY EVENING. AM CONCERNED THAT WINDS WILL PERSIST FRIDAY NIGHT
AT LEAST ACROSS THE MID-SLOPES AND THERMAL BELTS WHERE HUMIDITY
RECOVERY MAY BE THE POOREST. DO NOT DOUBT THAT THERE WILL BE A
PERIOD OF NON-CRITICAL CONDITIONS LATER FRIDAY NIGHT ESPECIALLY FOR
VALLEYS...BUT WITH ANY VALLEY INVERSIONS BEING SHALLOW AND EASILY
MIXED OUT...CRITICAL FIRE WEATHER CONDITIONS COULD RETURN AS EARLY
AS MID-MORNING SATURDAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 11 PM MDT THIS EVENING FOR COZ207.
FIRE WEATHER WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
EVENING FOR COZ200>203-207-290-292-293.
WIND ADVISORY UNTIL 11 PM MDT THIS EVENING FOR COZ018-019-
021>023.
UT...WIND ADVISORY UNTIL 11 PM MDT THIS EVENING FOR UTZ022.
&&
$$
UPDATE...PF
SHORT TERM...15
LONG TERM...JAD
AVIATION...15
FIRE WEATHER...JAD
AREA FORECAST DISCUSSION
NWS TAUNTON MA
122 PM EDT TUE MAY 22 2012
.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDANCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.
ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.
WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".
USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
* TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK
OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING. THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD. OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND. ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW. LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY. THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY. A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.
DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON. DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING. USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S. WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.
FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES. ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS. SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER. SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING. FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.
SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY. THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS. AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS. THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS. AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.
SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE. THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND. ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD. A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.
&&
.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
OVERVIEW...
MODERATE CONFIDENCE IN TAFS. PERSISTENT N/NE FLOW WILL KEEP LOW
CIGS LOCKED IN THROUGH WED MORNING AND AREAS OF FOG EXPECTED TO
BECOME WIDESPREAD AGAIN THIS EVENING. CIGS WILL BE SLOW TO IMPROVE
WED BUT AM CONFIDENT ON IMPROVEMENT TO VFR AROUND MIDDAY...EXCEPT
ON OUTER CAPE COD AND KACK WHERE LOW CIGS WILL PROBABLY REMAIN ALL
DAY. WEAK GRADIENT WILL BRING RETURN OF LOW CLOUDS/FOG WED NIGHT...
ESPECIALLY NEAR COAST.
KBOS TAF...MODERATE CONFIDENCE. TIMING OF LOWEST CONDITIONS
TONIGHT MAY BE A FEW HOURS TOO FAST. HIGHER CONFIDENCE ON TIMING
OF IMPROVEMENT WED.
KBDL TAF...MODERATE CONFIDENCE. TIMING OF IFR CIGS MAY BE A FEW
HOURS TOO FAST TONIGHT. HIGHER CONFIDENCE ON TIMING OF IMPROVEMENT
WED.
OUTLOOK...THURSDAY THOUGH SATURDAY...
THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE. DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.
&&
.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES. SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS. HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ235-237-254>256.
&&
$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...JWD
MARINE...KJC/RLG
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1020 AM EDT TUE MAY 22 2012
.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDANCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.
ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.
WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".
USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
* TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK
OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING. THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD. OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND. ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW. LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY. THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY. A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.
DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON. DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING. USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S. WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.
FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES. ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS. SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER. SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING. FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.
SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY. THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS. AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS. THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS. AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.
SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE. THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND. ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD. A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
OVERVIEW...
MODERATE CONFIDENCE IN TAFS. IFR/LIFR EXPECTED TO PREVAIL THROUGH
AFTERNOON NEAR COAST...WHILE CONDITIONS LOWER TO IFR ACROSS
INTERIOR. NOT MUCH HOPE FOR CIGS TO IMPROVE GIVEN CONTINUED
ONSHORE FLOW.
KBOS TAF...HIGH CONFIDENCE IN LIFR CONDITIONS THROUGH AFTERNOON.
KBDL TAF...HIGH CONFIDENCE IN CONDITIONS LOWERING TO IFR THIS
AFTERNOON.
OUTLOOK...WEDNESDAY NIGHT THOUGH SATURDAY...
WEDNESDAY NIGHT...LOW CONFIDENCE. MVFR WITH POCKETS OF IFR IN FOG
ALONG SOUTH COAST.
THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE. DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.
&&
.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES. SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS. HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ235-237-254>256.
&&
$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...JWD
MARINE...KJC/RLG
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1012 AM EDT TUE MAY 22 2012
.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDENCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.
ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.
WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".
USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
* TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK
OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING. THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD. OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND. ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW. LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY. THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY. A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.
DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON. DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING. USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S. WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.
FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES. ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS. SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER. SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING. FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.
SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY. THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS. AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS. THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS. AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.
SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE. THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND. ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD. A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
OVERVIEW...
MODERATE CONFIDENCE IN TAFS. IFR/LIFR CONDITIONS WILL LIKELY
PREVAIL FOR MUCH OF THE REGION THROUGH THE MORNING...POSSIBLY
LIFTING TO MVFR IN THE INTERIOR DURING THE AFTERNOON. CONDITIONS
DROPPING BACK TO IFR/LIFR TONIGHT BUT FOG MAY NOT BE AS DENSE AND
WIDESPREAD AS LOW LEVEL WINDS TURN S/SW. GRADUAL IMPROVEMENT TO
VFR/MVFR EXPECTED DURING WED WITH SCT SHOWERS/TSTMS POSSIBLE...BUT
MVFR/IFR CIGS COULD LINGER ALONG THE S COAST ALL DAY WED.
KBOS TAF...HIGH CONFIDENCE IN LIFR CONDITIONS THROUGH 14Z...THEN
IMPROVING VSBYS EXPECTED DURING THE DAY BUT CIGS LIKELY REMAINING
IFR THROUGH TONIGHT.
KBDL TAF...MODERATE CONFIDENCE. AREAS OF MVFR. CIGS MAY DROP BACK
TO IFR LATE TONIGHT.
OUTLOOK...WEDNESDAY NIGHT THOUGH SATURDAY...
WEDNESDAY NIGHT...LOW CONFIDENCE. MVFR WITH POCKETS OF IFR IN FOG
ALONG SOUTH COAST.
THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE. DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.
&&
.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES. SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS. HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ235-237-254>256.
&&
$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...KJC/RLG
MARINE...KJC/RLG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
611 PM EDT TUE MAY 22 2012
.SYNOPSIS...
A LOW PRESSURE SYSTEM SOUTHEAST OF CAPE COD WILL DRIFT NORTHEAST
TONIGHT AND WEDNESDAY. A HIGH PRESSURE SYSTEM WILL THEN BUILD IN
BEHIND IT OVER THE CANADIAN MARITIMES ON THURSDAY AND SLOWLY SINK
SOUTHWEST OVER THE MEMORIAL DAY WEEKEND AND BECOME ESTABLISHED OFF
THE SOUTHEAST UNITED STATES COAST. A BACKDOOR COLD FRONT WILL TRY
TO SAG SOUTH INTO THE AREA ABOUT SUNDAY BEFORE RETREATING NORTH ON
MEMORIAL DAY. A FRONT DOOR COLD FRONT WILL APPROACH THE AREA FROM
THE GREAT LAKES ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DESPITE BREAKS IN THE CLOUDS THIS AFTERNOON...THE SCATTERED SHOWER
ACTIVITY HAS BEEN SLOW TO EVOLVE LATE THIS AFTERNOON. IN FACT...TOPS
HAVE NOT GOTTEN TO MINUS 20 CELSIUS YET...AND THIS WOULD SEEM TO
EXPLAIN THE LACK OF LIGHTNING DATA TO THIS POINT. THE LOSS OF
DAYTIME HEATING SOON PROBABLY MEANS THE WINDOW OF OPPORTUNITY FOR
THUNDER WITH THE SCATTERED SHOWERS DEVELOPING NOW IS CLOSING...AND
COULD BE REMOVED FROM NORTHERN ZONES BEFORE 900 PM.
THE LATEST HRRR RUN IS TRYING TO DEVELOP A BROKEN LINE OF
THUNDERSTORMS IN THE BEST INSTABILITY. THIS LIES ACROSS WEST CENTRAL
PENNSYLVANIA (WHERE THE SUNSHINE HAD A BETTER CHANCE TO
DESTABILIZE THE AIRMASS. THE IN SITU BULK SHEAR PROFILE IS NOT
THAT IMPRESSIVE...AND DOES NOT APPEAR TO GET ANY BETTER INTO THE
LATER EVENING HOURS. WHILE THERE IS SOME ACTIVITY NOW IN THE AXIS
OF BEST INSTABILITY...IT IS UNCLEAR JUST HOW MUCH OF THIS ACTIVITY
SURVIVES TO THE LEHIGH VALLEY AFTER 800 PM.
FOR NOW...WILL LEAVE THE MENTION OF THUNDER IN DEFERENCE TO THE
ACTIVITY TO THE WEST. HOWEVER...IF IT DOES NOT GET BETTER
ORGANIZED AS IT MOVES EAST...IT COULD BE REMOVED FROM THE FORECAST
LATER TONIGHT.
THE NEXT FORECAST PROBLEM FOR TONIGHT IS THE LOW CLOUDS AND FOG.
THE LOW CLOUDS DID BREAK THIS AFTERNOON...AND PATCHES ARE TRYING
TO REFORM EARLY THIS EVENING. NAM MODEL SOUNDINGS SHOW THAT THE
REDEVELOPMENT OF STRATUS COULD TAKE SOME TIME...ESPECIALLY WEST OF
THE DELAWARE RIVER. BASED ON THE CURRENT CLOUD COVER AND THE NAM
MODEL SOUNDINGS...THE TIMING OF THE STRATUS REAPPEARANCE HAS BEEN
PUSHED BACK A BIT.
STATISTICAL GUIDANCE SUGGESTS THAT TONIGHT COULD END UP BEING A
A BETTER SETUP FOR AREAS OF FOG (MOIST LOW LEVELS...HIGH PRESSURE
TO THE NORTHEAST). HOWEVER...NAM MODEL SOUNDINGS SUGGEST THE THE
LOW LEVEL HYDROLAPSE RATES DO NOT BECOME FAVORABLE FOR UNTIL LATER
TONIGHT...AND FOR A SHORTER TIME THAT THE MOS GUIDANCE WOULD
INDICATE. AREAS OF FOG WAS LEFT IN THE FORECAST...AND TRENDS WILL
BE WATCHED TO LOOK FOR POTENTIAL FOR DENSE FOG LATER TONIGHT.
FOR THE MOST PART...TEMPERATURES AND WINDS APPEAR TO BE ON TRACK
FOR THE OVERNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
EXPECT PERIODS OF SHOWERS AND POSSIBLY THUNDERSTORMS DURG THE AFTN
AND THEY MAY BE MORE WIDESPREAD THAN TODAY ESPECIALLY IF WE GET MORE
BREAKS IN THE CLOUDS, BUT DON`T SEE ANY SIGNIFICANT FORCING
MECHANISMS. GUID TEMPS LOOK REASONABLE ONCE AGAIN.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE WRF-NMMB INITIALIZATION WAS BETTER THAN THE GFS OFF OF THE 12Z
SOUNDINGS AND THE FORMER WAS GIVEN MORE WEIGHT THAN AVERAGE TODAY.
BTW TODAY IS THE FIRST DAY OF THE NEW GFS. IN THE BIG PICTURE, NO
CHANGES TO OUR THINKING WITH MAINLY DIURNALLY DRIVEN LOCALIZED HEAVY
RAIN CONVECTION INTO FRIDAY. THEN MODEL UNCERTAINTIES AS TO THE
BACKDOOR ON THE WEEKEND WITH THE TREND TOWARD WARMER AND MORE
HUMID WEATHER INCORPORATED.
THERE SHOULD BE A DIURNAL DOWNTREND IN THE CONVECTION ON WEDNESDAY
EVENING AS FORECAST CAPES AND LI(S) DECREASE. WE DID SHOW AN UPTICK
IN POPS LATER AT NIGHT AS THE SHORT WAVE ASSOCIATED WITH THE CLOSING
SERN CONUS LOW COMES CLOSE TO THE AREA. BOTH THE GFS AND WRF-NMMB DO
SHOW SOME WEAK SFC BASED INSTABILITY AS THIS FEATURE SLIDES BY AND
WE MENTION SOME THUNDER LATE. GIVEN THE CONTINUED UPTICK IN DEW
POINTS, WE MAINTAINED THE MENTION OF PATCHY FOG LATE. A STAT
GUIDANCE COMPROMISE WAS USED FOR MINS.
ON THURSDAY, WE LEANED MORE TOWARD THE WRF-NMMB SOLUTION OF GIVING
THE CANADIAN MARITIMES HIGH A BIT MORE OF A BITE AND SHELTERING OF
OUR CWA FROM CONVECTION. IN REALITY GFS MOS SUPPORTS THE WRF-NMMB
SFC FEATURES MORE SO THAN THE GFS ITSELF. BOTH WOULD FAVOR MORE
ACTIVITY WEST VS EAST. CONCEIVABLY BEING RIGHT FOR THE WRONG
REASON, THE GFS BRINGS IN DRY AIR ALOFT IN THE EAST DURING THE
DAY ON THURSDAY WHICH WOULD MAKE IT HARDER FOR CONVECTION TO
OCCUR. WITHOUT ANY ORGANIZED TRIGGER WITH THE AFOREMENTIONED SHORT
WAVE MOVING FARTHER OFFSHORE IN THE MORNING, KEPT POPS AS CHANCE.
GIVEN MORE OF AN ONSHORE INFLUENCE FROM THE SFC HIGH AND HOW LONG
WILL IT TAKE TO CLEAR LOW CLOUDS, WE LEANED MAX TEMPS MUCH CLOSER TO
THE LOWER NAM MOS THAN GFS MOS.
WASH, RINSE, REPEAT ON THURSDAY NIGHT. BUT, WITHOUT A LATE SHORT
WAVE, WE DROPPED POPS AS THE NIGHT PROGRESSES AND REMOVED THE
MENTION OF THUNDER. THE WRF-NMMB SOLUTION SUPPORTS STRATUS AT THE
LEAST AND A SUGGESTION OF DRIZZLE AT THE MOST AS THE .01 PCPN
FIELD BOOMS LATE AT NIGHT. FOR NOW WE WENT THE PATCHY FOG ROUTE
AND ACCEPTED THE STAT GUIDANCE MINS.
ON FRIDAY, THE MODELS AGREE ON A SLIGHTLY MORE EAST PUSH IN THE
INSTABILITY AXIS, MAYBE INTO THE DELAWARE VALLEY. OTHER THAN
MESOSCALE FEATURES, I.E. DIFFERENTIAL HEATING, OROGRAPHIC LIFTING,
MAYBE SEA OR BAY BREEZES, NOT MUCH ORGANIZATIONAL ACTIVITY EXPECTED
AGAIN. POPS WERE AGAIN KEPT BELOW LIKELY. WE STILL PREFER MORE OF A
MODIFIED MARINE INFLUENCE FROM OUR SURFACE HIGH TO THE EAST THAN THE
GFS SHOWED AND WE THUS KEPT MAX TEMPS BLO MEX MOS.
BOTH THE GFS AND WRF-NMMB DID SHOW AN AXIS OF HIGHER INSTABILITY
WORKING ITS WAY INTO WESTERN PA DURING THE DAY ON FRIDAY. IF THE
CONVECTION COULD MAINTAIN ITSELF, IT WOULD GET INTO OUR CWA BEFORE
RUNNING OUT OF GAS ON FRIDAY NIGHT. WE DID UP POPS SLIGHTLY.
THERE REMAINS SOME UNCERTAINTY AS TO HOW SOUTH WILL THE BACKDOOR
FRONT GET OVER THE WEEKEND. RIGHT NOW IT APPEARS TO BE A DIFFERENCE
BETWEEN WARM WEATHER AND SOME TYPICAL SUMMERTIME CONVECTION AROUND
BECAUSE OF THE LINGERING FRONT, OR A COUPLE OF WARM SECTOR DAYS WITH
HIGH TEMPERATURES REACHING THE 90S ON THE COASTAL PLAIN AWAY FROM
THE OCEAN. THE MODELS CONTINUE TO GO BACK AND FORTH WITH THIS
SCENARIO. MORE CONSENSUS ODDLY ABOUT HOT WEATHER ON MONDAY AND
TUESDAY. WE NUDGED MAX TEMPS UPWARD WITH THIS PACKAGE AND
MAINTAINED LOW POPS BECAUSE OF THE UNCERTAINTY OF THE FRONTAL
POSITION.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
CONDS HAVE IMPROVED TO MVFR AND EVEN VFR IN SOME LOCATIONS AS LATEST
SATELLITE IMAGERY SHOWED THE CLOUDS HAVE THINNED. EXPECT THESE
TRENDS TO CONTINUE INTO THE EARLY EVENING BEFORE WE GET A REPEAT
PERFORMANCE ONCE AGAIN. CLOUDS WILL LOWER AND THICKEN AND EVERYONE
WILL BE MVFR/IFR AND EVEN LIFR DURG THE OVERNIGHT AND EARLY MORNING
HOURS BEFORE SOME IMPROVEMENT AGAIN DURG WEDNESDAY.
THE WIND SHOULD BE LIGHT AND GENLY FROM THE E AR SE.
OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY...IFR CONDS EACH NIGHT AND EARLY
EACH DAY IN STRATUS AND/OR FOG BECOMING VFR IN THE AFTN. LOCAL IFR
CONDS IN SHOWERS OR TSTMS. OUTLOOKING LESS COVERAGE AND DURATION
OF IFR AND MVFR CONDITIONS ON FRIDAY THAN THURSDAY.
SATURDAY AND SUNDAY...POSSIBLY SOME MVFR OR IFR STRATUS OR FOG EARLY
OTHERWISE VFR. ISOLATED THUNDERSTORMS POSSIBLE MAINLY LATE EACH DAY
WITH MVFR CONDITIONS.
&&
.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY WILL CONTINUE AND SEAS HAVE
BEEN ABOVE SCA FOR MOST OF THE DAY. THIS WILL CONTINUE THROUGH THE
NIGHT, BUT LTST GUIDANCE INDICATES THE SRN WATERS WILL RETREAT BELOW
SCA VALUES ON WEDNESDAY. ACRS THE N, THINGS MAY LINGER LONGER.
HOWEVER, FOR NOW, WILL LET THE PREV ISSUED SCA CONTINUE WITH NO
CHANGES, BUT IT MAY NEED TO BE EXTENDED FOR A FEW HOURS, ESPECIALLY
ACRS THE N.
OUTLOOK...
WE ARE NOT EXPECTING SMALL CRAFT ADVISORY CONDITIONS TO OCCUR
THROUGHOUT THE OUTLOOK PERIOD AS THE ONSHORE FLOW FROM THE CANADIAN
MARITIMES SHOULD NOT BE THAT STRONG AND EVEN IF WE GET A BACKDOOR
FRONT, WINDS ARE NOT EXPECTED TO BE STRONG EITHER. THE GREATER
MARINE CONCERNS WILL BE FOG AS DEW POINTS SHOULD RISE ABOVE THE
WATER TEMPS. THIS MAY THE CASE EVERY MORNING INTO SUNDAY. ALSO
THERE MAY BE STRONGER WINDS NEAR THUNDERSTORMS, ALTHOUGH THE
GREATEST INSTABILITY IS EXPECTED TO BE WEST OF THE COASTAL WATERS.
&&
.HYDROLOGY...
THERE WILL PROBABLY BE NARROW SWATHS OF 72 HOUR TOTAL 1-3 INCH RFALL
BETWEEN TONIGHT AND FRIDAY...MAINLY IN E PA AND POSSIBLY NNJ. PWATS
THIS WEEK AROUND 1.4 INCHES INCREASE TO AT LEAST 1.75 INCHES THIS
WEEKEND.
&&
.RIP CURRENTS...
THE SOUTHEAST SWELL SHOULD BE DROPPING TONIGHT INTO WEDNESDAY.
WHILE THE PERIOD REMAINS FAIRLY LONG (NEAR 9 SECONDS)...THE SURF
HEIGHT SHOULD COME DOWN AS WELL. BASED ON THE ABOVE...OUR LOCAL
STUDY SHOWS THE NEW JERSEY COAST COMING IN AT MODERATE...AND THE
DELAWARE COAST COMING IN WITH A LOW RISK OF RIP CURRENTS
WEDNESDAY. THE ABOVE WILL BE REFLECTED IN THE EVENING SURF ZONE
FORECAST FOR WEDNESDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ450>455.
&&
$$
SYNOPSIS...GIGI
NEAR TERM...HAYES/NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...GIGI/99
AVIATION...DRAG/GIGI/NIERENBERG
MARINE...GIGI/NIERENBERG
HYDROLOGY...DRAG
RIP CURRENTS...HAYES
AREA FORECAST DISCUSSION
NWS MIAMI FL
951 PM EDT WED MAY 23 2012
.UPDATE...CHALLENGING FORECAST. LOCAL AREA HAS COME UNDER
SUBSIDENCE TODAY AS EVIDENCED BY LITTLE CONVECTION. WE WERE IN THE
SUBSIDENCE SIDE OF A DEPARTING JET. 500 MB TEMP HAS WARMED QUITE A
BIT...NOW AT -6.9C ON THE EVENING MIAMI SOUNDING. SO NOT AS
UNSTABLE. CONVECTION HAS REMAINED GENERALLY OFF THE SE FL COAST
ALL DAY, THOUGH A FEW SHOWERS AND STORMS DID DEVELOP OVER THE
INTERIOR AND GULF COAST. CONVECTION OVER THE ATLANTIC HAS NOW EVEN
DIMINISHED. HOWEVER, THERE IS A SHORTWAVE OVER THE NORTH CENTRAL
GULF HEADING ESE...AND MODELS INDICATE MORE FAVORABLE JET DYNAMICS
LATE TONIGHT AND ESPECIALLY THURSDAY. HOWEVER, GFS/ECMWF CONSENSUS
IS TO KEEP THE BEST CONVERGENCE/HEAVY RAIN JUST OFF TO OUR
SOUTHEAST...AS A SURFACE/LOW LEVEL TROUGH AXIS LIES ALONG THE SE
FL COAST. BUT SE FLOW IS STRENGTHENING SOME AND THIS COULD
INCREASE COASTAL CONVERGENCE ALONG THE ATLANTIC COAST OVERNIGHT.
THE LATEST HRRR SHOWS SHOWERS DEVELOPING AND MOVING NW ONSHORE THE
ATLANTIC COAST LATER TONIGHT, ALTHOUGH IT`S OVERDOING ACTIVITY
CURRENTLY.
SO HERE`S THE BOTTOM LINE - THE MOST FAVORED AREA OVERNIGHT
THROUGH THURSDAY FOR HEAVY RAIN LOOKS TO BE OFF OUR ATLANTIC
COAST. HOWEVER, GIVEN HIGH MOISTURE AND POSSIBLE COASTAL
CONVERGENCE, WILL MAINTAIN POPS AS IS. STILL LIKE THE FLOOD WATCH
FOR MIAMI- DADE COUNTY THROUGH 8 PM THU...GIVEN THE EXTREME
RAINFALL WHICH OCCURRED FROM THE SWEETWATER-DORAL AREAS ON TUESDAY
WITH STANDING WATER REMAINING IN AREAS. IT WON`T TAKE MUCH RAIN TO
CAUSE FLASH FLOODING ACROSS THESE HARD HIT LOCALES. /GREGORIA
&&
.PREV DISCUSSION... /ISSUED 741 PM EDT WED MAY 23 2012/
AVIATION...
SOUTH FLORIDA IS AT THE EDGE OF DEEP TROPICAL MOISTURE TO THE EAST
AND ISOLATED CONVECTIVE ACTIVITY TO THE WEST. THE EAST COAST
TERMINALS INCLUDE VCSH AFTER MIDNIGHT SINCE MOST GUIDANCE INSISTS
IN INCREASING THE SHOWER ACTIVITY OVER NIGHT NEAR THE EAST COAST.
HOWEVER, THIS IS A LOW CONFIDENCE FORECAST. FOR THURSDAY WE EXPECT
SHOWERS AND THUNDERSTORMS TO BECOME MORE WIDESPREAD IN THE
AFTERNOON AND EVENING. ALL TAF LOCATIONS INCLUDE THE CHANCE FOR
VCTS FOR THURSDAY AFTERNOON. WINDS ARE EXPECTED TO BE FROM THE
EAST SOUTHEAST BELOW 10 KNOTS.
PREV DISCUSSION... /ISSUED 659 PM EDT WED MAY 23 2012/
UPDATE...CONVECTION TODAY HAS BEEN VERY MINIMAL DUE TO BROAD
SCALE SUBSIDENCE. HOWEVER, AS A SHORTWAVE OVER THE NORTH CENTRAL
GULF AS SEEN ON WATER VAPOR IMAGERY IS MOVING RATHER FAST TO THE
EAST. THIS COULD INDUCE SOME OF THE HIGHER MOISTURE OVER THE
ATLANTIC, AND ASSOCIATED RAINFALL, TO MOVE TOWARDS THE NW AND
ONSHORE THE SE FLORIDA COAST OVERNIGHT. UNCERTAIN FORECAST TONIGHT
AND THURSDAY AS WE ARE ON THE EDGE OF DEEP CARIBBEAN MOISTURE AND
TROUGH AXIS. WILL MAINTAIN THE CHANCE POPS TONIGHT. FLOOD WATCH
REMAINS IN EFFECT FOR MIAMI-DADE COUNTY THROUGH 8 PM THURSDAY FOR
THE POTENTIAL FOR ADDITIONAL RAINS LEADING TO FLASH FLOODING.
/GREGORIA
PREV DISCUSSION... /ISSUED 348 PM EDT WED MAY 23 2012/
FLOOD WATCH EXTENDED UNTIL THURSDAY EVENING FOR MIAMI-DADE COUNTY...
POSSIBLE STRONG TO EVEN SEVERE STORMS FOCUSED INTERIOR THIS AFTERNOON...
DISCUSSION...
EARLY THIS AFTERNOON...A MID TO UPPER LEVEL LOW WAS LOCATED OVER THE
CAROLINAS WITH A TROUGH OF LOW PRESSURE EXTENDING SOUTHWEST
THROUGH THE CWA AND INTO THE NORTHWEST CARIBBEAN SEA WHERE A WEAK
SURFACE LOW PRESSURE SYSTEM WAS LOCATED. THE NATIONAL HURRICANE
CENTER AT THIS TIME IS GIVING THE SURFACE LOW IN THE NORTHWEST
CARIBBEAN SEAS A NEAR 0 PERCENT CHANCE OF DEVELOPMENT DURING THE
NEXT 48 HOURS.
THE MID TO UPPER LEVEL LOW WILL MOVE NORTHEAST KEEPING THE TROUGH
OF LOW PRESSURE IN PLACE OVER THE CWA TONIGHT INTO THURSDAY...AS
THE WEAK SURFACE LOW MOVES NORTHEAST AND THROUGH SOUTH FLORIDA OR
JUST TO THE EAST OF SOUTH FLORIDA. THIS WILL KEEP THE STEERING
FLOW IN PLACE ALONG WITH THE DEEP TROPICAL MOISTURE WORKING INTO
THE SOUTHERN PORTION OF THE CWA FROM THE NORTHWEST CARIBBEAN SEA.
THE LATEST PWAT`S FROM THE FORECAST MODELS ARE STILL SHOWING 2 TO
2.4 INCHES OVER THE SOUTHERN AREAS OF THE CWA LATE TONIGHT INTO
THURSDAY WHICH IS CLOSE TO THE ALL TIME MAXIMUM PWAT FOR THIS
TIME OF YEAR. THIS WILL ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS
TO CONTINUE OVER THE EAST COAST METRO AREAS TAPERING DOWN TO
ISOLATED OVER THE INTERIOR AND WEST COAST METRO AREAS. ON
THURSDAY...THE ACTIVITY COULD INCREASE TO SCATTERED COVERAGE OVER
THE INTERIOR AREAS TO NUMEROUS COVERAGE OVER THE EAST COAST METRO
AREAS. THEREFORE...A FLOOD WATCH FOR MIAMI-DADE COUNTY HAS BEEN
EXTENDED THROUGH THURSDAY EVENING...DUE TO THE GROUND BEING VERY
SATURATED FROM THE PREVIOUS RAINS OVER THE PAST COUPLE OF DAYS AND THE
POTENTIAL OF MORE LOCALLY HEAVY RAINFALL TONIGHT INTO THURSDAY.
THE WEAK LOW WILL THEN MOVE INTO WESTERN ATLANTIC WATERS PUSHING
THE TROUGH OF LOW PRESSURE SOUTHWARD INTO THE FLORIDA KEYS. THIS
WILL ALLOW FOR DRIER AIR TO WORK INTO THE CWA FROM THE NORTH FOR
FRIDAY INTO THIS WEEKEND WHICH IN TURN WILL REDUCE THE COVERAGE OF
THE SHOWERS AND THUNDERSTORMS OVER THE CWA. THE BEST CHANCE OF
SHOWER AND THUNDERSTORM ACTIVITY WILL BE OVER THE INTERIOR AND
WEST COAST METRO AREAS THIS WEEKEND...DUE TO THE NORTHEAST
STEERING FLOW BEHIND THE TROUGH OF LOW PRESSURE.
EXTENDED FORECAST...
THE LATEST LONG RANGE MODELS ARE NOW SPLITTING ON THE RETURN
MOISTURE TO THE AREA FOR EARLY TO MIDDLE OF NEXT WEEK. THE 23/00Z
RUN OF THE ECMWF LONG RANGE MODEL TRIES TO BRING THE LOW BACK TO THE
FLORIDA PENINSULA ALONG WITH THE DEEP MOISTURE...WHILE THE 23/12Z GFS
MODEL PUSHES THE LOW EASTWARD TAKING THE DEEP TROPICAL MOISTURE
WITH IT. SO AT THIS TIME WILL CONTINUE TO SHOW SCATTERED SHOWERS
AND THUNDERSTORMS OVER THE CWA FOR EARLY TO MIDDLE OF NEXT
WEEK...UNTIL THE MODELS BECOME MORE IN LINE WITH EACH OTHER FOR
EARLY TO MIDDLE OF NEXT WEEK.
MARINE...
THE WINDS OVER THE CWA WATERS WILL REMAIN AT 15 KNOTS OR LESS
TONIGHT INTO THIS WEEKEND WHILE SWINGING FROM A SOUTHERLY
DIRECTION TONIGHT TO A NORTHERLY DIRECTION THIS WEEKEND. THE ONLY
EXCEPTION TO THIS IS IN THE ATLANTIC WATERS WHERE THE WINDS WILL
BE 15 TO 20 KNOTS TONIGHT. THE SEAS WILL ALSO REMAIN BELOW 6 FEET
FOR BOTH THE ATLANTIC AND GULF WATERS OF SOUTH FLORIDA TONIGHT
THROUGH THIS WEEKEND. SO WILL CONTINUE THE SCEC FOR THE ATLANTIC
WATERS DUE TO THE WIND SPEEDS.
FIRE WEATHER...
THE RELATIVE HUMIDITIES WILL REMAIN ABOVE THE 35 PERCENT CRITICAL
VALUE THROUGH THE WEEKEND. SO NO PROBLEMS WITH THE FIRE WEATHER
PRODUCT.
HYDROLOGY...
FOR DETAILS ON THE RAINFALL AMOUNTS ACROSS SOUTH FLORIDA PLEASE SEE
THE FLOOD WATCH AND THE HYDROLOGIC OUTLOOK STATEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 86 75 89 / 40 50 30 20
FORT LAUDERDALE 75 86 77 88 / 50 70 40 20
MIAMI 74 87 76 89 / 50 70 40 20
NAPLES 73 89 74 90 / 20 40 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH THURSDAY EVENING FOR COASTAL MIAMI DADE-FAR
SOUTH MIAMI DADE-INLAND MIAMI DADE-METRO MIAMI DADE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1019 AM EDT Tue May 22 2012
.MESOSCALE UPDATE...
The convective forecast for today was complicated by thunderstorms
that that had moved southeast across Alabama overnight and then
dissipated over the past 1-2 hours near the northwest corner of
our forecast area. Basically no model handled this activity with
any kind of skill; to illustrate that point, none of the models in
a 25-member storm scale ensemble model from OU/CAPS had any storms
in the area of TOI/DHN prior to 15z. The global models and other
higher resolution models produced similar results.
11z HRRR model run finally initialized the small cluster of storms
and related cold pool fairly well. It also correctly shows the new
convection developing along a surface trough axis just offshore.
Therefore, this was used as the basis for our forecast updates
this morning.
Initial development of storms today appears most likely 15-17z
(in the next 3 hours) near the I-65 corridor, or just to the
northwest of our forecast area. This is the scenario portrayed by
the HRRR, low-level convergence is increasing in this area on the
NW side of the residual cold pool / outflow, and an ACCAS field is
in the process of developing. The HRRR then develops things east
to ABY-MAI-DTS by 19z (3pm EDT). We will also need to keep an eye
on the storm cluster offshore, as it would be on track to clip the
Cape San Blas area around 16z if it holds together.
Severe threat still looks to be mainly damaging winds. Deep
inverted-V signature still showing up in the sub-cloud layer on
most of the model forecast soundings. Maximum delta theta-e values
are around 20-25C as well, on the lower cusp of favorable
downburst parameter space. With deep mixing expected today,
dewpoints are likely to fall back into the 50s. Modifying the 12z
TAE sounding for surface conditions of about 88/56 yields SBCAPE
around 1000 j/kg. The BMX sounding just upstream shows a mid-level
temperature profile about 1-2C cooler as it was launched into the
cold pocket of air aloft at the center of the digging shortwave.
If mid-level temperatures in the NW part of our area cool to the
BMX profile - it would add about 600 j/kg of CAPE to the sounding.
With steepening mid-level lapse rates, some hail to around 1 inch
in diameter couldn`t be ruled out either. Slight Risk by SPC still
looks on target. We are expecting scattered thunderstorms. Most of
the storms will produce some sort of gusty winds, and a few that
can build taller cores or deeper/stronger cold pools could produce
some wind gusts up to around 50kt.
High temperatures were nudged up closer to observed values from
yesterday as the low-level temperature profile has changed very
little in the past 24 hours. Grid/product updates will be out
shortly.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 64 91 65 93 / 50 30 20 10 10
Panama City 84 69 88 67 91 / 40 20 20 10 10
Dothan 90 65 93 66 94 / 60 30 20 10 10
Albany 90 64 91 65 93 / 50 30 20 10 10
Valdosta 92 63 91 64 92 / 50 40 20 10 10
Cross City 90 65 90 64 92 / 20 20 20 10 20
Apalachicola 85 67 86 68 84 / 30 10 20 10 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for Calhoun-Gadsden-Holmes-Inland Jefferson-Inland
Walton-Jackson-Lafayette-Leon-Liberty-Madison-Washington.
GM...None.
&&
$$
08-Lamers
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
432 AM EDT Tue May 22 2012
...Strong to severe thunderstorms possible today...
.SYNOPSIS...
The 02 UTC regional surface analysis showed a typically weak late
May pressure pattern, except behind a weak cold front that stretched
from western TN to northern LA. There were also several outflow
boundaries from either earlier or ongoing storm complexes. In fact,
it`s difficult at times to distinguish the synoptic front from the
outflow boundaries. Vapor imagery and upper air data showed a broad
long wave trough over the Southeast U.S., with one vorticity max
ejecting northeastward off the Mid Atlantic Coast as another
was digging quickly southeastward over AL. Precip water values
have recovered to near climatology over much of our forecast area.
Strangely enough, isolated thunderstorms were developing
sporadically across our forecast area at 4 am, which is unusual
for this time of year. In fact, a loosely-organized complex of
thunderstorms was just northwest of the Elba and Ozark area in
Southeast AL.
&&
.SHORT TERM...
(Today through Thursday) A good portion of our forecast area is
under a "Slight Risk" (15% chance of a severe storm within 25 miles
of a point) of severe storms today, as the aforementioned upper
trough temporarily closes off over north GA later today. The cold
pool aloft will steepen our 700-500 mb lapse rates to the 6.5 to
7.5 deg C range, which is fairly substantial for our region. In
addition, a 500 mb level jet max is forecast to develop across our
area by this afternoon, increasing the 0-6 km vertical wind shear
magnitude to about 30 KT. This could help produce at least some
storm organization. Judging from the upstream reports over the
past 12 to 24 hours with this system, we can expect reports of
marginally severe hail (generally in the penny to quarter size
range) and damaging wind gusts in the 45 to 60 MPH range. It is
not clear how (or if) the loosely-organized thunderstorms just
northwest of our area will impact our forecast for the evolution
of today`s convection (either the amount or severity). None of the
CAM models or HRRR initialized this feature, so we are are "winging
it" a bit in the very near term. Our best guess is that is will weaken
considerably as it moves into the northwest portions of our
forecast area this morning. More storms will likely develop
later, especially in the afternoon. The incoming day shift can re-
evaluate this as needed.
Much drier air will quickly advect from west to east this
evening, bringing an end to the storms. GFS and NAM MOS have
almost no PoP for our region Wednesday because of this very dry
air aloft, but the Convection Allowing Models are managing to
generate scattered convective cells. We introduced a 20 percent
PoP for Wednesday afternoon in case a few updrafts survive the
hostile upper level environment. The only PoP we show for Thursday
is around Cross City and Perry, where there may be a bit more
moisture as weak disturbance moves quickly northeastward across
the FL Peninsula.
We expect temperatures to be near average during the mornings,
and a few degrees above average in the afternoons, with the
warmest day being Thursday (with highs in the lower to mid 90s
inland). The relative humidity will remain low enough during the
afternoons to prevent the uncomfortable muggy conditions we would
typically expect in a few weeks.
.LONG TERM...
(Thursday night through next Tuesday) Most of the extended period
will be dominated by a strong upper ridge building over the
eastern CONUS becoming centered across the Ohio Valley this
weekend. The axis of the surface ridge will extend east to west
from the western Atlantic through the Central Plains. As a result,
the local region will be under deep layer easterly flow. Monday
through Tuesday the upper ridge is forecast to break down as a
shortwave tracks from the northern Plains to the Great Lakes
region. Meanwhile, the surface ridge slides southward and weakens
with low level flow veering to the southeast to south. The only
relief from the anticipated above seasonal temperatures will be
scattered convection over the weekend and early next week from the
influx of moisture off the Atlantic. Max temperatures across
inland areas will be in the lower to mid 90s. Min temps will
generally be in the lower 70s.
&&
.AVIATION...
A brief period of MVFR vsby restriction at VLD is possible before
sunrise. Otherwise, VFR conditions will prevail with just brief MVFR
vsbys in afternoon and evening convection. Some of the storms may be
strong to severe. Winds will be from the southwest around 10 knots
outside of convection.
&&
.MARINE...
Winds and seas will remain at typically low May values through
Friday, except for some higher winds and seas this afternoon and
evening (and again on Wednesday) near the coast due to the sea
breeze circulation enhancement.
&&
.FIRE WEATHER...
The minimum relative humidity should be above 35 percent today
across north Florida today with scattered showers and thunderstorms
by afternoon. A drier airmass filters back into the region on
Wednesday and a Fire Weather Watch remain in place for interior
portions of north Florida. These areas could see relative humidities
less than 35 percent combined with dispersions greater than 75 and
ERCs greater than 20.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 64 91 65 93 / 50 30 20 10 10
Panama City 84 69 88 67 91 / 40 20 20 10 10
Dothan 90 65 93 66 94 / 60 30 20 10 10
Albany 90 64 91 65 93 / 50 30 20 10 10
Valdosta 92 63 91 64 92 / 50 40 20 10 10
Cross City 90 65 90 64 92 / 20 20 20 10 20
Apalachicola 85 67 86 68 84 / 30 10 20 10 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for Calhoun-Gadsden-Holmes-Inland Jefferson-Inland
Walton-Jackson-Lafayette-Leon-Liberty-Madison-Washington.
GM...None.
&&
$$
LONG TERM/AVIATION/FIRE WX...Barry
Rest of Discussion...Fournier
AREA FORECAST DISCUSSION
NWS GOODLAND KS
540 PM MDT WED MAY 23 2012
.SHORT TERM...(THIS AFTERNOON THROUGH TONIGHT)
ISSUED AT 1245 PM MDT WED MAY 23 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
ACROSS THE NORTHERN ROCKIES...WITH WEST/SOUTHWEST FLOW ACROSS THE
INTER-MOUNTAIN WEST INTO THE CENTRAL HIGH PLAINS. AT THE SURFACE A COLD
FRONT HAS STALLED OVER WESTERN KANSAS...CURRENTLY ACROSS THE EASTERN
PART OF THE CWA.
A SHORTWAVE TROUGH CURRENTLY OVER THE GREAT BASIN WILL MOVE
EAST-NORTHEAST ACROSS NORTH CENTRAL COLORADO AND SOUTHWEST NEBRASKA
TONIGHT. SHOWERS/THUNDERSTORMS HAVE ALREADY DEVELOPED AHEAD OF THIS
FEATURE ALONG THE FRONT RANGE INTO SOUTHEASTERN WYOMING. THIS
ACTIVITY WILL SPREAD SOUTH AND EAST OVER OUR CWA LATER THIS
AFTERNOON...WITH COVERAGE INCREASING ACROSS THE NORTHERN PART OF OUR
FORECAST AREA THROUGH 06Z. CONVERGENCE ZONE ALONG AND NORTH OF
STALLED FRONT COULD ACT AS A FOCUS FOR EARLIER THUNDERSTORM
INITIATION LATER THIS AFTERNOON AND EVENING...HOWEVER THIS IS
REMOVED FROM LARGE SCALE ASCENT ASSOCIATED WITH SHORTWAVE SO
COVERAGE SHOULD BE LIMITED ACROSS THE SOUTH. VERY STRONG SHEAR IS
PRESENT ACROSS THE CWA...WITH INSTABILITY DECREASING THE FURTHER
NORTH IN THE CWA WHERE TD VALUES IN THE 30-40F RANGE HAVE ADVECTED
IN BEHIND THE FRONT. SEVERE CONVECTION SHOULD BE LIMITED TO THE I-70
CORRIDOR THROUGH EARLY EVENING WHERE THE BEST OVERLAP BETWEEN
SHEAR/INSTABILITY IS EXPECTED. LATER TONIGHT ELEVATED INSTABILITY
COULD COMBINE WITH STRONG UPPER LEVEL DYNAMICS ASSOCIATED WITH THE
SHORTWAVE ACROSS SOUTHWEST NEBRASKA TO BRING ADDITIONAL SEVERE
CHANCES. SUBSIDENCE QUICKLY BUILDS IN BEHIND DEPARTING SHORTWAVE
TROUGH AFTER 06Z...WITH COVERAGE DECREASING FROM THE SOUTHWEST TO
THE NORTHEAST THROUGH SUNRISE THURSDAY.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 224 PM MDT WED MAY 23 2012
THURSDAY-THURSDAY NIGHT...PV ANOMALY WILL LIFT TO THE NORTH AND EAST
OF THE AREA FAIRLY QUICKLY DURING THE MORNING HOURS...WITH MID LEVEL
FRONTOGENESIS QUICKLY DIMINISHING AND DEEP LAYER DIV Q FIELDS
INDICATE FAIRLY STRONG LARGE SCALE FORCING FOR SUBSIDENCE OVER THE
AREA. STILL HAVE A FEW TIMING CONCERNS THOUGH...AND THINK HOLDING
ONTO SOME SMALL POPS WARRANTED FOR AT LEAST THE FIRST FEW HOURS OF
THE PERIOD. SOUNDINGS SUGGEST THAT WEAK INSTABILITY WILL LINGER
ACROSS MUCH OF THE AREA THROUGH THE DAY...AS DIFFERENTIAL TEMP
ADVECTION SHOULD LEAD TO THE DEVELOPMENT OF SHALLOW SFC BASED
INSTABILITY WITH EQUILIBRIUM LEVELS LESS THAN H5 AT MANY LOCATIONS.
ALTHOUGH SUBSIDENCE DIMINISHES IN THE AFTERNOON ACROSS SOUTHERN HALF
OF CWA...THINKING ANY AFTERNOON SHOWERS WILL BE STRONGLY DIURNALLY
DRIVEN AND THINK OVERALL COVERAGE WILL BE FAIRLY LOW THROUGH THE
EARLY EVENING. LARGE SCALE ASCENT WILL ONCE AGAIN WITH STRONG LOW
LEVEL WAA DEVELOPING IN RESPONSE TO H3 JET STREAK LIFTING NORTH INTO
SOUTHERN SOUTH DAKOTA. SEEMS LIKE RECENT SUITE OF MODELS NOT ALL
THAT OPTIMISTIC ABOUT BREAKING OUT PRECIPITATION OVERNIGHT...BUT
GIVEN STRONG AND PERSISTENT WAA/ISENTROPIC FORCING STRONG MOISTURE
TRANSPORT ABOVE THE SFC...AND SMALL CONDENSATION PRESSURE DEFICITS
IN AREA OF NEGATIVE THETA E LAPSE RATES...THINK THE THREAT FOR
SHOWERS AND STORMS WILL BE THERE DESPITE CURRENT MODEL QPF OUTPUT.
FRIDAY-SATURDAY...WARM FRONT WILL SLOWLY LIFT TO THE NORTH THROUGH
THE PERIOD AND WILL NOT ONLY PLAY A BIG ROLE ON POTENTIAL FOR
THUNDERSTORMS...IT WILL ALSO HAVE A LARGE ROLE IN TEMPERATURE
FORECAST AS POSSIBILITY EXISTS FOR A PRETTY SHARP GRADIENT WITH
TEMPS ON FRIDAY. SREF PLUME DATA INDICATING NEARLY A 20 DEGREE
SPREAD IN TEMPS FOR MOST LOCATIONS...WITH ABOUT EQUAL CLUSTERING ON
EITHER SIDE...MAINLY ON FRIDAY. PLAN ON KEEPING NEAR MEAN VALUES FOR
FRIDAY...ALTHOUGH THERE IS MUCH MORE AGREEMENT ON VERY WARM TEMPS ON
SATURDAY AND HAVE WARMED TEMPS ACCORDINGLY.
GIVEN EXPECTED PRESSURE FALL PATTERN AROUND AREA AND LARGE SCALE
FORCING FOR ASCENT BECOMING MAXIMIZED WELL TO THE WEST OF THE
AREA...DO NOT ANTICIPATE MUCH OF A NORTHERN MOVEMENT OF THE
FRONT...WITH BULK OF CWA REMAINING CLOUDY AND COOL THROUGH THE DAY.
THINK THUNDERSTORMS WILL LIKELY BE ONGOING THROUGH THE MORNING HOURS
AS PREVIOUSLY MENTIONED WAA PATTERN REMAINS IN PLACE THROUGH THE
MORNING HOURS...BEFORE LARGE SUBSIDENCE INVERSION STRENGTHENS DURING
THE AFTERNOON SHARPLY INCREASING CINH PROFILES AND ADVECTING MUCH
DRIER AIR INTO THE AREA. MODELS CONTINUE TO PRODUCE LIGHT
PRECIPITATION AFTER THIS POINT...BUT SOUNDINGS LOOK LIKE ANY
PRECIPITATION PROCESSES IN THE LATE AFTERNOON OR EVENING LOOK TO BE
VERY SHALLOW/DRIZZLE TYPE PROCESSES AND DO NOT PLAN ON GOING ALONG
WITH HIGHER GUIDANCE POPS AT THIS TIME. APPEARS TO BE LOTS OF
INSTABILITY DURING THE LATE AFTERNOON AND EVENING ALONG/NORTH OF
FRONT...BUT CINH LOOKS VERY STRONG AND GIVEN RIDGING ALOFT DO NOT
THINK THIS WILL BE OVERCOME.
ON SATURDAY...EXPECT WINDY TO VERY WINDY CONDITIONS TO DEVELOP
ACROSS MUCH OF THE AREA DURING THE AFTERNOON WITH STRONGEST WINDS
BEHIND DRYLINE IN EASTERN COLORADO...WHERE DEEP MIXED LAYER SHOULD
TAP INTO STRONG FLOW ALOFT. WITH TEMPS IN THE 90S...WIND GUSTS
APPROACHING 50 KTS AND MIXED TDS SUGGESTING A RAPID DROP OFF IN
DEWPOINTS...POTENTIAL EXISTS FOR EXTREMELY CRITICAL FIRE WX
CONDITIONS TO DEVELOP. IT IS A BIT TOO FAR IN THE FUTURE TO ISSUE
ANY HIGHLIGHTS AT THIS POINT...BUT POTENTIAL FOR FIRE WEATHER AND
SIGNIFICANT WINDS IS INCREASING. OTHERWISE...WARM FRONT WILL LIFT TO
THE NORTH OUT OF THE AREA DURING THE MORNING HOURS WITH ANY
POTENTIAL FOR AFTERNOON THUNDERSTORMS ALONG DRYLINE DURING THE LATE
AFTERNOON. WITH DEEP MIXING AND BULK OF PRESSURE FALLS TO THE NORTH
OF THE AREA...WOULD EXPECT DRYLINE TO MIX EASTWARD WITH BULK OF CWA
IN DRY SECTOR. ENOUGH SPREAD EXISTS TO WARRANT A MORE BROAD BRUSHED
APPROACH TO CHANCES ATTM THOUGH AND WITH STRONG FLOW ALOFT THERE
WILL BE POTENTIAL FOR AT LEAST A FEW STRONG/SEVERE HIGH BASED STORMS
IN THE AFTERNOON.
IN THE EXTENDED (SAT NIGHT-WEDNESDAY)...ACTIVE WEATHER PATTERN
EXPECTED THROUGH THE PERIOD AS MEDIUM RANGE MODELS SHOWING
REASONABLE AGREEMENT IN DEVELOPMENT OF STRONG TROUGH/AMPLIFIED
PATTERN ACROSS THE PLAINS THROUGH THE WEEKEND...FOLLOWED BY MORE
ZONAL FLOW ALOFT DURING THE BEGINNING OF THE WEEK. WHILE 06Z GEFS
DATA SHOWS A RELATIVELY CONSISTENT PATTERN WITH LARGE TROUGH
IMPACTING THE AREA DURING THE WEEKEND...MODEL SPREAD/UNCERTAINTY
INCREASES DURING THE LATER HALF AS THERE APPEARS TO BE A DECENT
AMOUNT OF DISCREPANCY WITH SMALL SCALE FEATURES. BEST CHANCE FOR
PRECIPITATION WILL LIKELY BE ON SUNDAY AFTERNOON AS COLD FRONT
SLOWLY MOVES ACROSS THE AREA PROVIDING AMPLE FORCING TO FOCUS
THUNDERSTORM DEVELOPMENT. WITH LIGHT EASTERLY/UPSLOPE FLOW AND
SEVERAL FAST MOVING SHORT WAVE TROUGHS MOVING THROUGH ZONAL
FLOW...PRECIP CHANCES WILL CONTINUE THROUGH THE MIDDLE OF THE WEEK.
ASIDE FROM TIMING WITH FROPA ON SUNDAY BRINGING THE POTENTIAL FOR
ONE MORE VERY WARM DAY...LOOKS LIKE COOLER CONDITIONS WILL PREVAIL
THROUGH THE START OF THE WEEK AS LIGHT EASTERLY FLOW WILL PREVAIL
BEHIND COLD FRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 534 PM MDT WED MAY 23 2012
CURRENT RADAR DETECTING SHOWERS AND A FEW THUNDERSTORMS MOVING
EAST FROM EASTERN COLORADO. THESE STORMS SHOULD IMPACT BOTH KGLD
AND KMCK LATER THIS EVENING. SOME MVFR CONDITIONS ARE POSSIBLE
NEAR THUNDERSTORMS. OTHERWISE MID LEVEL CLOUDS SHOULD CLEAR OUT BY
MID MORNING AS SHORTWAVE EXITS THE REGION. WINDS WILL BECOME GUSTY
BY LATE MORNING AND CONTINUE IN THE AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 224 PM MDT WED MAY 23 2012
VERY WINDY CONDITIONS...WITH GUSTS IN EXCESS OF 50 MPH
POSSIBLE...ARE EXPECTED ACROSS A LARGE PORTION OF THE AREA ON
SATURDAY. AFTERNOON HUMIDITIES WILL FALL TO AROUND 10 PERCENT
ACROSS PORTIONS OF EASTERN COLORADO AND ADJACENT AREAS DURING THE
AFTERNOON AS THE WINDS INCREASE. THE COMBINATION OF VERY DRY AND
VERY WINDY CONDITIONS WILL BRING THE POTENTIAL FOR EXTREMELY
CRITICAL CONDITIONS ON SATURDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JRM
AVIATION...FS
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
620 PM CDT WED MAY 23 2012
...UPDATED AVIATION SECTION...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 142 PM CDT WED MAY 23 2012
NAM, RAP, AND HRRR WERE IN DECENT AGREEMENT WITH COLD FRONT
EXTENDING FROM NORTH CENTRAL KANSAS INTO EXTREME SOUTHWEST KANSAS
LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS FRONT WILL BE
LOCATED UNDER +14C TO +16C 700MB TEMPERATURES. IN ADDITION THE
BETTER LOW LEVEL MOISTURE IS STILL FORECAST TO BE LOCATED ACROSS
CENTRAL KANSAS AND FROM NORTHWEST KANSAS INTO SOUTH CENTRAL
NEBRASKA. BASED ON MODEL SOUNDINGS THE WARM MID LEVEL TEMPERATURES
LATE TODAY/EARLY TONIGHT APPEARS TO SERVE AS A CAP ACROSS MOST OF
SOUTHWEST KANSAS. THE POSSIBLE EXCEPTION WILL BE NEAR AND NORTH OF
INTERSTATE 70 IN NORTH CENTRAL KANSAS WERE BETTER LOW LEVEL
FRONTOGENESIS AND MOISTURE WILL BE PRESENT. IN ADDITION THIS WILL
BE NEAR THE NORTHERN EDGE OF THE WARM MID LEVEL TEMPERATURES. THE
NAM EVEN SUGGESTS SOME COOLING OCCURRING IN THE MID LEVEL AFTER
21Z ALONG AND NORTH OF INTERSTATE 70. GIVEN THE COOLER MID LEVEL
TEMPERATURES, BETTER LOW LEVEL MOISTURE/FRONTOGENESIS NEAR THE
SURFACE BOUNDARY, AND CAPES EARLY TONIGHT GREATER THAN 1000 J/KG
WILL GO AHEAD AND KEEP A MENTION OF THUNDERSTORMS NEAR THE SURFACE
BOUNDARY. ALSO BASED ON 0-6KM SHEAR FORECAST TO BE AROUND 50
KNOTS ALONG WITH 1000-2000 J/KG THERE WILL BE A CHANCE FOR ANY
STORM THAT DOES DEVELOP TO BECOME SEVERE. MAIN HAZARD STILL
APPEARS TO BE HAIL UP TO HALF DOLLAR SIZE AND WINDS UP TO 60 MPH.
FURTHER WEST...THE CONVECTION DEVELOPING ACROSS NORTHEAST COLORADO IS
EXPECTED TO SPREAD EAST EARLY TONIGHT BUT STAY NORTH OF THE
INTERSTATE 70 DURING THE OVERNIGHT HOURS. THE COLD POOL THAT IS
FORECAST TO DEVELOP WITH THESE STORMS OVERNIGHT SHOULD PUSH THE
COLD FRONT SOUTH ACROSS ALL OF SOUTHWEST KANSAS AFTER MIDNIGHT. BY
EARLY THURSDAY MORNING THIS COLD FRONT IS EXPECTED TO BE LOCATED
ACROSS CENTRAL KANSAS AND NORTHERN OKLAHOMA. BOUNDARY LAYER WINDS
BEHIND THIS FRONT ARE FORECAST TO RANGE FROM 30 TO 35 KNOTS AND
GIVEN THE TIGHT PRESSURE GRADIENT BEHIND THIS FRONT THE SURFACE WINDS
MAY APPROACH ADVISORY CRITERIA FOR A FEW HOURS FOLLOWING THE
FRONTAL PASSAGE LATE TONIGHT. AT THIS TIME HAVE DECIDED TO KEEP
SUSTAINED WINDS JUST BELOW ADVISORY CRITERIA FOR A FEW HOURS
BEHIND THIS FRONT. IN ADDITION TO THE WINDS SOME LOW LEVEL
MOISTURE WILL RETURN TO NORTH CENTRAL AND SOUTHWEST KANSAS. THE
WRF AND NMM EVEN SUGGESTS SOME LIGHT PRECIPITATION WILL BE
POSSIBLE AS THE LOWER LEVELS SATURATES. AT THIS TIME GIVEN THE ISENTROPIC
DOWNGLIDE PRESENT AND DEPTH OF THE MOIST LAYER LESS THAN 3000 FEET
AM TRENDING AWAY FROM INSERTING PRECIPITATION CHANCES AFTER
MIDNIGHT.
ON THURSDAY THE GUSTY NORTHWEST WINDS WILL GRADUALLY SUBSIDE BY
MID MORNING AS THE COLD FRONT CONTINUES TO MOVE SOUTHEAST ACROSS
EASTERN KANSAS AND OKLAHOMA. IN SOUTHEAST COLORADO THIS FRONT IS
EXPECTED TO BECOME NEARLY STATIONARY DURING THE DAY WITH SOME
ISENTROPIC LIFT/WARM AIR ADVECTION DEVELOPING NORTH OF THIS
BOUNDARY BY LATE DAY. THIS MAY BRING AN INCREASE IN MID LEVEL CLOUD
COVER LATE DAY TO PORTIONS OF SOUTHWEST KANSAS BASED ON I310 AND
I315 ISENTROPIC SURFACES AND 12Z BUFR SOUNDINGS. GIVEN SOME
INCREASING CLOUDS LATE DAY AND 850MB TEMPERATURES AT 00Z FRIDAY
WILL TREND TOWARDS THE COOLER GUIDANCE IN FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WHILE FURTHER NORTH HAVE KEPT HIGHS
CLOSER TO THE WARMER 850MB MIX DOWN TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 234 PM CDT WED MAY 23 2012
THURSDAY NIGHT:
NOT THAT IMPRESSED FOR PROSPECTS OF CONVECTION THURSDAY EVENING. SOME
ISENTROPIC LIFT IS EXPECTED ALONG THE 700 HPA BAROCLINIC BOUNDARY ACROSS
CENTRAL KANSAS. FORECAST SOUNDINGS FROM THE ECMWF/GFS SHOW THAT THERE
MAY BE SOME MID LEVEL CLOUDS, HOWEVER, THE OVERALL PROFILE IS FAIRLY
DRY AND CAPPED. WENT AHEAD AND THREW IN SOME SILENT POPS ACROSS MY NORTHERN
COUNTIES BUT DISCOUNTED THE WETTER GFS SOLUTION WHICH CONTINUES TO SUFFER
FROM OVERALL POOR SYNOPTIC PERFORMANCE. THE 4 KM NAM & ARW/NMM CORES
AREN`T TOO CONVINCING EITHER.
FRIDAY:
THE WARM SECTOR WILL CONTINUE TO SPREAD NORTHWARD DOWNSTREAM OF A SLOWLY
PROPAGATING 500 HPA TROUGH FURTHER WEST. TEMPERATURES WARM TO 33 DEG
C @ 850 HPA AND 15 DEG C & 700 HPA WITH A WELL MIXED ATMOSPHERE. HAVE
WARMED TEMPERATURES TO THE MID TO UPPER 90S DEG F ACROSS THE CENTRAL
AND SOUTHERN ZONES AS A RESULT. THE ECMWF IS VERY WARM WITH 102 DEG
F FOR DODGE CITY FRIDAY. WILL CONTINUE TO THE TREND UPWARD BUT NOT YET
BITE ON THE EXTREME. THERE COULD BE SOME CONVECTION EAST OF THE DRYLINE
FRIDAY EVENING BUT WITH SUCH WARM TEMPERATURES AT 700 HPA, WILL NOT
GO HIGHER THAN SLIGHT GIVEN THE VERY STOUT EML. ECMWF SHOWS ABOUT 2500
J/KG OF SBCAPE AND 30 TO 40 KT OF SHEAR SO WILL HAVE TO WATCH OUT
FOR SEVERE IN LATER FORECASTS.
SATURDAY:
AMPLIFICATION OF THE WESTERN TROUGH IS EXPECTED SATURDAY. THE 12Z ECMWF
IS LESS AGGRESSIVE WITH CONVECTION FOR SATURDAY EVENING ACROSS THE WEST
THAN COMPARED TO THE 00Z RUN. THIS IS PROBABLY DUE TO THE CONTINUED
STRONG EML FORECAST BY THE MODEL. WILL NOT GO HIGHER THAN SLIGHT POPS
IN THE MEANTIME. NOT MUCH UPPER LEVEL SUPPORT AS THE MAIN 250 HPA JET
AXIS IS STILL PRETTY FAR WEST. WILL CONTINUE HOT TEMPERATURES IN THE
GRIDS WITH MID TO UPPER 90S DEG F EXPECTED ACROSS MUCH OF THE REGION.
SUNDAY AND BEYOND:
CONVECTIVE PROSPECTS ARE BETTER SUNDAY AS THE RIGHT ENTRANCE REGION
OF THE AFOREMENTIONED 250 HPA TRAVERSES ACROSS NW KANSAS. CAA ASSOCIATED
WITH THE TROUGH AND LOW TO MID LEVEL COLD POOLS WILL ALLOW FOR A WEAKENING
OF THE EML. THE BEST CHANCE FOR CONVECTION APPEARS TO BE ACROSS CENTRAL
AND SOUTH CENTRAL KANSAS ALONG AND EASTWARD MIXING DRYLINE. THE
THERMODYNAMIC AND KINEMATIC PROFILES ARE SUPPORTIVE OF SEVERE WEATHER.
UL FLOW FLATTENS MONDAY AND TUESDAY AS THE ASSOCIATED TROUGH MOVES ACROSS
THE CANADIAN PRAIRIES. THIS WILL ALLOW FOR MORE SEASONAL YET ABOVE NORMAL
TEMPERATURES ACROSS SW KANSAS. WILL HAVE TO WATCH THE MIDWEEK PERIOD
NEXT WEEK AS IT TRANSITIONS INTO MORE OF A MCS PATTERN. DEWPOINTS/MOISTURE
COULD BE AN ISSUE THOUGH. HAVE GONE WITH A CLEANED UP VERSION OF ALLBLEND
POPS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 620 PM CDT WED MAY 23 2012
A FRONTAL BOUNDARY WILL CONTINUE TO MOVE SLOWLY THROUGH THE TAF
SITES OVERNIGHT TONIGHT SHIFTING WINDS FROM A SOUTHERLY DIRECTION
TO THE NORTH NORTHEAST. GUSTY CONDITIONS WILL CONTINUE AHEAD AND
BEHIND THIS SYSTEM WITH VARIABLE WINDS ALONG THE COLD FRONT. VFR
CONDITIONS WILL PREVAIL WITH HIGH CLOUDS AOA100-200.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 55 83 62 97 / 0 0 10 10
GCK 53 82 60 96 / 10 0 10 10
EHA 56 85 59 96 / 0 0 10 10
LBL 54 85 62 100 / 0 0 10 10
HYS 55 80 59 86 / 30 10 10 20
P28 65 85 67 97 / 0 0 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CDT THIS EVENING FOR KSZ066-080-081-089-
090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...SUGDEN
AVIATION...HOVORKA 42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
234 PM CDT TUE MAY 22 2012
...UPDATE TO LONG TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 1218 PM CDT TUE MAY 22 2012
A 500MB UPPER TROUGH WAS LOCATED NEAR THE SOUTHWEST COAST OF BRITISH
COLUMBIA AND NORTHWEST WASHINGTON AT 12Z TUESDAY. A 120-140KT
UPPER LEVEL JET WAS PLACE NEAR AND JUST SOUTHWEST OF THE BASE OF
THIS UPPER TROUGH. 90-110 METER HEIGHT FALLS WERE OBSERVED ACROSS
EASTERN IDAHO AND WESTERN MONTANA. A WESTERLY FLOW EXTENDED
ACROSS THE ROCKIES INTO THE WESTERN HIGH PLAINS WITH +12 TO +13C
700MB TEMPERATURES STRETCHING FROM EASTERN WYOMING/WESTERN
NEBRASKA INTO NORTHEAST NEW MEXICO. UNDER THESE WARM 700MB
TEMPERATURES AT THE SURFACE THERE WAS A TROUGH OF LOW PRESSURE
ACROSS WESTERN NEBRASKA AND EXTREME EASTERN COLORADO/FAR WESTERN
KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 128 PM CDT TUE MAY 22 2012
RAP, NAM AND HRRR PLACE THE SURFACE TROUGH OF LOW PRESSURE NEAR
THE COLORADO BORDER THIS EVENING. MODEL SOUNDINGS AT 00Z
WEDNESDAYS IN THIS AREA INDICATING LITTLE TO NO CIN WITH A
TEMPERATURES DRY ADIABATIC UP TO AROUND THE 600MB LEVEL WHERE SOME
MOISTURE IS PRESENT. ALSO OBSERVING SOME INSTABILITY PRESENT AS
WELL SO AM UNABLE TO COMPLETELY RULE OUT A EARLY EVENING
THUNDERSTORM DEVELOPING NEAR THE COLORADO BORDER EARLY THIS
EVENING. RAP AND HRRR DO HINT AT A FEW STORMS DEVELOPING AFTER 22Z
NEAR THE ELKHART WHERE THE BETTER INSTABILITY ARE FORECAST TO BE
LOCATED. WITH THIS IN MIND THE PREVIOUS PRECIPITATION FORECAST FOR
EXTREME SOUTHWEST KANSAS STILL APPEARS TO BE ON TRACK. ALSO BASED
ON THE INVERTED V TYPE OF SOUNDINGS IT DOES APPEAR THAT STRONG
WINDS UP TO 60 OR 70 MPH WILL BE THE MAIN HAZARD. ANY STORM THAT
DOES DEVELOP EARLY THIS EVENING IS EXPECTED TO END BEFORE MIDNIGHT
BUT MAY MOVE AS FAR EAST AS LIBERAL IF THESE A COLD POOL CAN BE
DEVELOPED FROM STORMS. AFTER MIDNIGHT SOUTH WINDS OF 15 TO 25 MPH
ARE EXPECTED TO CONTINUE AND BASED ON TEMPERATURES EARLIER THIS
MORNING WILL FAVOR OVERNIGHT LOWS AROUND 5F WARMER THAN GUIDANCE.
ON WEDNESDAY A SURFACE TROUGH/DRYLINE WILL SLIDE EAST INTO
WESTERN KANSAS DURING THE DAY AS A COLD FRONT DROPS SOUTH INTO
NORTHWEST KANSAS BY LATE MORNING. THE COLD FRONT IS EXPECTED TO BE
LOCATED FROM WEST CENTRAL KANSAS AND NORTH CENTRAL KANSAS BY THE
MID AFTERNOON AS WARM MID LEVEL TEMPERATURES SPREADS EAST ACROSS
SOUTHWEST KANSAS. MODEL SOUNDINGS INDICATING ANOTHER DAY OF GOOD
MIXING AND BASED ON MODEL SOUNDINGS AT 00Z THURSDAY IT CURRENTLY
APPEARS HIGHS AROUND 100 DEGREES WILL STILL BE POSSIBLE WEST OF
THE DRYLINE. EAST OF THE DRYLINE AND NEAR THE COLD FRONT THE HIGHS
WILL BE SLIGHTLY COOLER AND RANGE FROM THE LOW TO MID 90S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 234 PM CDT TUE MAY 22 2012
WEDNESDAY NIGHT:
A FRONTAL BOUNDARY COULD BE THE IMPETUS FOR CONVECTION WEDNESDAY NIGHT
MAINLY ACROSS THE INTERSTATE 70 CORRIDOR. MARGINAL SURFACE DEWPOINTS
IN THE 50S DEG F AND VERY WARM MAXIMUM TEMPERATURES IN THE 90S DEG F
ACROSS CENTRAL KANSAS WILL CONTRIBUTE TO 1500 TO 2500 J/KG OF SBCAPE.
AN 850 HPA THETA-E AXIS WILL ALSO EXIST ACROSS WEST CENTRAL KANSAS WITH
BROAD SOUTHWESTERLY FLOW ALOFT WHICH POINT TO FAVORABLE CONDITIONS FOR
CONVECTION. SEVERE WEATHER CANNOT BE RULED OUT WITH 40 TO 50 KT OF BULK
0 TO 6 KM SHEAR.
THURSDAY:
A BROAD 500 HPA TROUGH IS EXPECTED FROM THE PACIFIC NORTHWEST TOWARDS
THE NORTHERN PLAINS. ANOTHER VORTMAX MOVING DOWNSTREAM WILL USHER
IN A COLD FRONT EXTENDING FROM THE UPPER MIDWEST TO SOMEWHERE IN
KANSAS. I SAY SOMEWHERE BECAUSE THERE IS PRETTY LARGE SPATIAL DIFFERENCES
BETWEEN THE ECMWF/GFS. THIS IS PARTICULARLY TRUE WHEN THE FRONT RETURNS
AS A WARM FRONT LATE THURSDAY. DECIDED TO TAKE THE MORE AGGRESSIVE
ECMWF APPROACH WITH THE NORTHWARD PROGRESSION OF THIS WARM FRONT. SOUTH
OF THIS FRONT, LOW LEVEL TEMPS ARE EXPECTED TO BE VERY WARM (30 DEG
C @ 850 HPA/15 DEG C @ 700 HPA), SO HAVE KEPT LOWER 90S DEG F TOWARDS
THE OKLAHOMA BORDER AND "COOLER" 80S DEG F ACROSS WEST CENTRAL KANSAS.
NOT EXPECTING ANY CONVECTION AS A RESULT OF THE EML ADVECTION ACROSS
SW KANSAS.
FRIDAY:
A WAA PATTERN WILL STRENGTHEN FRIDAY WITH THE EML SPREADING FURTHER
NORTH AND 850 HPA TEMPERATURES WARMING TO 33 DEC C. 700 HPA TEMPERATURES
WILL ALSO BE VERY WARM AND NEAR 16 DEG C. THERE MIGHT BE AN ISOLATED
STORM NEAR HAYS FRIDAY EVENING, BUT AM DUBIOUS OF THIS GFS SOLUTION
SO HAVE KEPT POPS IN SLIGHT CATEGORY GIVEN THE STOUT EML. THERE IS ALSO
NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS 500 HPA HEIGHT INCREASES
ARE EXPECTED ACROSS THE REGION ASSOCIATED WITH MID LEVEL SHORTWAVE RIDGING.
TEMPERATURES WILL BE HOT AND IN THE 90S DEG F. IF THE ECMWF SOLUTION
IS CORRECT, THEN A 100 DEGREE DAY IS POSSIBLE FOR SOME LOCATIONS AND
TEMPERATURES NEED TO BE INCREASED IN THE FUTURE.
SATURDAY AND BEYOND:
FOLLOWED THE ECMWF SOLUTION FOR THIS PERIOD. A VERY BROAD MID LEVEL
TROUGH IS EXPECTED ACROSS THE GREAT BASIN. ANY JET LEVEL DYNAMICS
LOOK TO REMAIN WELL NORTH OF KANSAS WITH GREATEST CHANCE OF HIGHER
IMPACT SEVERE WEATHER NORTH OF THE REGION. THERE COULD BE SOME STORMS
ACROSS SOUTHWEST KANSAS THROUGH THE WEEKEND, HOWEVER, THE ATMOSPHERE
LOOKS PRETTY CAPPED. MADE A FEW TWEAKS TO THE ALLBLEND POPS (CLEANED
UP) AND WARMED TEMPERATURES UP WITH A BIAS TOWARDS THE ECMWF.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1218 PM CDT TUE MAY 22 2012
A TIGHT PRESSURE GRADIENT COMBINED WITH 30-40KT WINDS IN THE
900-850MB LEVEL WILL RESULT SUSTAINED WINDS OF AROUND 25 KNOTS
THROUGH THE REMAINDER OF THE DAY...ESPECIALLY AT DDC AND HYS.
THESE GUSTY WINDS WILL SUBSIDE SOME AFTER SUNSET BUT BASED ON THE
SURFACE PRESSURE GRADIENT SUSTAINED WIND SPEEDS OF 15 TO 20 KNOTS
STILL APPEARS LIKELY. A LOW LEVEL JET IS FORECAST TO DEVELOP
TOWARDS 06Z WITH WIND SPEEDS OF 50 TO 55 KNOTS BETWEEN 1500 AND 2000 FEET
SO INSERTED A WIND SHEAR GROUP INTO THE TAFS OVERNIGHT. BUFR
SOUNDINGS CONTINUE TO INDICATE VFR CONDITIONS OVER THE NEXT 24
HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 97 63 86 / 0 10 10 10
GCK 64 98 58 85 / 0 10 10 10
EHA 63 99 58 91 / 20 0 10 10
LBL 65 102 61 89 / 20 0 10 10
HYS 67 93 61 83 / 0 20 20 10
P28 66 93 70 89 / 0 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...SUGDEN
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
131 PM CDT TUE MAY 22 2012
...UPDATED SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 1218 PM CDT TUE MAY 22 2012
A 500MB UPPER TROUGH WAS LOCATED NEAR THE SOUTHWEST COAST OF BRITISH
COLUMBIA AND NORTHWEST WASHINGTON AT 12Z TUESDAY. A 120-140KT
UPPER LEVEL JET WAS PLACE NEAR AND JUST SOUTHWEST OF THE BASE OF
THIS UPPER TROUGH. 90-110 METER HEIGHT FALLS WERE OBSERVED ACROSS
EASTERN IDAHO AND WESTERN MONTANA. A WESTERLY FLOW EXTENDED
ACROSS THE ROCKIES INTO THE WESTERN HIGH PLAINS WITH +12 TO +13C
700MB TEMPERATURES STRETCHING FROM EASTERN WYOMING/WESTERN
NEBRASKA INTO NORTHEAST NEW MEXICO. UNDER THESE WARM 700MB
TEMPERATURES AT THE SURFACE THERE WAS A TROUGH OF LOW PRESSURE
ACROSS WESTERN NEBRASKA AND EXTREME EASTERN COLORADO/FAR WESTERN
KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 128 PM CDT TUE MAY 22 2012
RAP, NAM AND HRRR PLACE THE SURFACE TROUGH OF LOW PRESSURE NEAR
THE COLORADO BORDER THIS EVENING. MODEL SOUNDINGS AT 00Z
WEDNESDAYS IN THIS AREA INDICATING LITTLE TO NO CIN WITH A
TEMPERATURES DRY ADIABATIC UP TO AROUND THE 600MB LEVEL WHERE SOME
MOISTURE IS PRESENT. ALSO OBSERVING SOME INSTABILITY PRESENT AS
WELL SO AM UNABLE TO COMPLETELY RULE OUT A EARLY EVENING
THUNDERSTORM DEVELOPING NEAR THE COLORADO BORDER EARLY THIS
EVENING. RAP AND HRRR DO HINT AT A FEW STORMS DEVELOPING AFTER 22Z
NEAR THE ELKHART WHERE THE BETTER INSTABILITY ARE FORECAST TO BE
LOCATED. WITH THIS IN MIND THE PREVIOUS PRECIPITATION FORECAST FOR
EXTREME SOUTHWEST KANSAS STILL APPEARS TO BE ON TRACK. ALSO BASED
ON THE INVERTED V TYPE OF SOUNDINGS IT DOES APPEAR THAT STRONG
WINDS UP TO 60 OR 70 MPH WILL BE THE MAIN HAZARD. ANY STORM THAT
DOES DEVELOP EARLY THIS EVENING IS EXPECTED TO END BEFORE MIDNIGHT
BUT MAY MOVE AS FAR EAST AS LIBERAL IF THESE A COLD POOL CAN BE
DEVELOPED FROM STORMS. AFTER MIDNIGHT SOUTH WINDS OF 15 TO 25 MPH
ARE EXPECTED TO CONTINUE AND BASED ON TEMPERATURES EARLIER THIS
MORNING WILL FAVOR OVERNIGHT LOWS AROUND 5F WARMER THAN GUIDANCE.
ON WEDNESDAY A SURFACE TROUGH/DRYLINE WILL SLIDE EAST INTO
WESTERN KANSAS DURING THE DAY AS A COLD FRONT DROPS SOUTH INTO
NORTHWEST KANSAS BY LATE MORNING. THE COLD FRONT IS EXPECTED TO BE
LOCATED FROM WEST CENTRAL KANSAS AND NORTH CENTRAL KANSAS BY THE
MID AFTERNOON AS WARM MID LEVEL TEMPERATURES SPREADS EAST ACROSS
SOUTHWEST KANSAS. MODEL SOUNDINGS INDICATING ANOTHER DAY OF GOOD
MIXING AND BASED ON MODEL SOUNDINGS AT 00Z THURSDAY IT CURRENTLY
APPEARS HIGHS AROUND 100 DEGREES WILL STILL BE POSSIBLE WEST OF
THE DRYLINE. EAST OF THE DRYLINE AND NEAR THE COLD FRONT THE HIGHS
WILL BE SLIGHTLY COOLER AND RANGE FROM THE LOW TO MID 90S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE MAY 22 2012
MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH OF LOW PRESSURE
DROPPING SOUTHEAST ACROSS THE NORTHERN ROCKIES WEDNESDAY THEN
TURNING EASTWARD ACROSS THE WESTERN HIGH PLAINS OF NORTHEASTERN
COLORADO AND WESTERN NEBRASKA WEDNESDAY NIGHT BRINGING WIDESPREAD
PRECIP CHANCES TO THE DAKOTAS SOUTHWARD INTO NEBRASKA AND
POTENTIALLY NORTHERN KANSAS INTO THURSDAY. AN ATTENDANT COLD
FRONT IS PROJECTED TO PUSH SOUTH INTO WESTERN KANSAS SOMETIME EARLY
THURSDAY BEFORE STALLING OUT SOMEWHERE ACROSS SOUTHWEST KANSAS OR
POSSIBLY EVEN NORTHERN OKLAHOMA AS ANOTHER SURFACE LOW DEVELOPS
ACROSS NORTHEASTERN NEW MEXICO AND THE PANHANDLES REGION. HOWEVER,
THE BEST DYNAMIC SUPPORT ALOFT WILL REMAIN JUST TO OUR NORTH ACROSS
NEBRASKA AND POSSIBLY NORTHERN KANSAS WITH A STRONG +100KT UPPER
LEVEL JET EXITING EASTWARD OUT OF THE ROCKIES. SHOWERS AND
THUNDERSTORMS ARE LIKELY TO DEVELOP WEDNESDAY NIGHT INTO THURSDAY
ALONG THE APPROACHING FRONTAL BOUNDARY FROM THE UPPER MIDWEST DOWN
INTO NEBRASKA BUT ARE EXPECTED REMAIN JUST OFF TO OUR NORTH AND
NORTHEAST WHERE THE BEST UPPER LEVEL SUPPORT WILL BE. FOR THE MOST
PART, DRIER CONDITIONS ARE EXPECTED ACROSS SOUTHWEST AND SOUTH
CENTRAL KANSAS THROUGH THE END OF THE WEEK.
TEMPERATURES WILL REMAIN WELL ABOVE NORMAL WEDNESDAY AS A DEEPENING
SURFACE LOW IN EXTREME EASTERN COLORADO CONTINUES TO INFLUENCE A
SOUTH TO SOUTHWESTERLY LOW LEVEL FLOW INTO WESTERN KANSAS. THIS WILL
ENHANCE WARM AIR ADVECTION INTO THE AREA WITH H85 TEMPERATURES IN
THE MID TO UPPER 20S(C) ACROSS CENTRAL KANSAS TO JUST ABOVE 30C IN
SOUTHWEST KANSAS. LOOK FOR WIDESPREAD 90S(F) WEDNESDAY AFTERNOON
WITH NEAR 100F POSSIBLE IN EXTREME SOUTHWEST KANSAS. TEMPERATURES
WILL DROP THURSDAY IN RESPONSE TO A COLD FRONT PUSHING ACROSS
WESTERN KANSAS EARLY IN THE DAY. THIS WILL ALLOW COOLER AIR TO
FILTER SOUTH INTO THE AREA WITH H85 TEMPERATURES IN THE LOW TO MID
20S(C) ACROSS CENTRAL AND SOUTHWEST KANSAS. HOWEVER, HIGHS COULD BE
AN ISSUE CLOSER TO THE OKLAHOMA BORDER WHERE THE FRONTAL BOUNDARY IS
EXPECTED TO STALL OUT. A WARMING TREND IS THEN LIKELY INTO THE
WEEKEND AS UPPER LEVEL TROUGHING SETS UP ACROSS THE INTERMOUNTAIN
WEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1218 PM CDT TUE MAY 22 2012
A TIGHT PRESSURE GRADIENT COMBINED WITH 30-40KT WINDS IN THE
900-850MB LEVEL WILL RESULT SUSTAINED WINDS OF AROUND 25 KNOTS
THROUGH THE REMAINDER OF THE DAY...ESPECIALLY AT DDC AND HYS.
THESE GUSTY WINDS WILL SUBSIDE SOME AFTER SUNSET BUT BASED ON THE
SURFACE PRESSURE GRADIENT SUSTAINED WIND SPEEDS OF 15 TO 20 KNOTS
STILL APPEARS LIKELY. A LOW LEVEL JET IS FORECAST TO DEVELOP
TOWARDS 06Z WITH WIND SPEEDS OF 50 TO 55 KNOTS BETWEEN 1500 AND 2000 FEET
SO INSERTED A WIND SHEAR GROUP INTO THE TAFS OVERNIGHT. BUFR
SOUNDINGS CONTINUE TO INDICATE VFR CONDITIONS OVER THE NEXT 24
HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 96 62 88 / 0 10 10 10
GCK 64 98 60 85 / 10 10 10 10
EHA 62 99 60 87 / 20 10 10 10
LBL 65 102 62 88 / 10 10 10 10
HYS 65 92 63 84 / 0 10 10 10
P28 66 92 68 92 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1053 AM MDT TUE MAY 22 2012
.UPDATE...
ISSUED AT 1049 AM MDT TUE MAY 22 2012
TEMPERATURES WARMING RAPIDLY ACROSS THE NW CWA...WITH POINTS
ALREADY NEARING 90 DEGREES BEFORE 17Z. HRRR AND RUC CATCHING ONTO
THIS RAPID WARMING PRETTY WELL AND TRENDED FORECAST IN THIS
DIRECTION...WITH SOME VALUES NEAR 100 POSSIBLE IN THE NW PORTION
OF THE COUNTY. STILL ASSESSING NEED FOR ANY FIRE HIGHLIGHTS AS
LOWEST HUMIDITIES CURRENTLY IN AREA OF LIGHTEST WINDS...AND STILL
SOMEWHAT UNCLEAR HOW FAR EAST DRYLINE WILL MIX.
UPDATE ISSUED AT 813 AM MDT TUE MAY 22 2012
12Z RAOBS INDICATED DEEP LAYER OF NEARLY DRY ADIABATIC LAPSE RATES
HAVE EXPANDED TO THE EAST FROM 24 HOURS AGO...WITH LBF OBSERVING
VERY STEEP LAPSE RATES BETWEEN H8 AND H65...WITH HIGH LAPSE RATES
EXTENDING UP TO H45. MIXING OUT MORNING INVERSION ONLY REQUIRES
TEMPS IN THE MID 80S AND REDUCES CINH TO AROUND 50 J/KG. WITH
TEMPS EXPECTED TO BE WARMER THAN THAT AND DEEPER MOISTURE EXPECTED
TO THE EAST OF DRYLINE...THINK SMALL THREAT FOR THUNDERSTORMS
EXISTS THIS AFTERNOON AND EVENING. NEAR SFC FORCING WILL BE
STRONGEST ALONG DRYLINE...WHERE OVERALL MOISTURE PROFILES WILL BE
MUCH SHALLOWER...WHICH MAY LIMIT CONVECTIVE INITIATIONS AS
AVAILABLE MOISTURE FOR PARCELS IS DILUTED WITH DEEP MIXING. HAVE
MODIFIED FORECAST TO ACCOUNT FOR SOME LATE AFTERNOON STORMS ALONG
DRY LINE...BUT OVERALL COVERAGE WILL BE LOW.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 230 AM MDT TUE MAY 22 2012
TODAY...VERY WARM WITH RECORD OR NEAR RECORD HIGH TEMPERATURES
POSSIBLE FOR MANY. FULL 850 MIXING WOULD SUPPORT HIGHS IN THE MID
TO UPPER 90S. HOWEVER...MET/MAV GUIDANCE AND BIAS CORRECTED GRIDS
A FEW DEGREES COOLER. THINKING THAT THE STRONG SOUTH WINDS (NOT
TERRIBLY FAVORABLE FOR STRONG WARMING COMPARED TO A SOUTHWEST OR
WEST DIRECTION) WHICH MAY FLIRT WITH ADVISORY CRITERIA GUSTS IN
THE NORTON AND HILL CITY AREAS AND PLENTIFUL LOW LEVEL MOISTURE
(DEWPOINTS IN THE 50S) MAY PUT A DENT IN THE FULL MIXING AND
PRODUCE HIGHS CLOSER TO THE MET/MAV GUIDANCE. HAVE SPLIT THE TWO
SCENARIOS AND GONE WITH HIGHS IN THE LOW TO MID 90S.
WILL KEEP SILENT POPS GOING ALONG/NEAR THE CO/KS BORDER LATE THIS
AFTERNOON WHERE LOW LEVEL FORCING AND MID LEVEL MOISTURE MAY
CREATE SOME HIGH BASED CU/TCU.
TONIGHT...COLD FRONT MOVES INTO THE NORTHWEST PORTION OF THE AREA
BY SUNRISE. OTHERWISE...DRY WITH MILD OVERNIGHT LOWS IN THE MID
50S TO MID 60S.
WEDNESDAY...STILL NO CLEAR SOLUTION AS TO WHERE THE COLD FRONT
GETS HUNG UP WHICH WILL PLAY A CRUCIAL ROLE IN HIGH TEMPERATURES.
RIGHT NOW IT APPEARS AREAS SOUTH OF THE INTERSTATE WILL CONTINUE
ON THE HOT SIDE WITH HIGHS IN THE LOW TO MID 90S...MAYBE EVEN A
BIT HOTTER. NORTH OF THE FRONT HIGHS GENERALLY IN THE 80S. POST
FRONTAL MOISTURE INCREASES VERY LATE IN THE DAY AS AN UPPER TROUGH
APPROACHES THE AREA. PRECIPITATION CHANCES WILL REMAIN NORTH OF
THE INTERSTATE WITH THE BEST CHANCE ACROSS THE FAR NORTH/NORTHWEST
PORTIONS OF THE AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 230 AM MDT TUE MAY 22 2012
WEDNESDAY NIGHT-THURSDAY NIGHT...GOOD MOISTURE/JET ENERGY AND MID
LEVEL FORCING SUPPORT HIGH CHANCE POPS ACROSS THE NORTHERN 1/4 OF
THE AREA...SIMILAR TO PREVIOUS FORECASTS WEDNESDAY NIGHT. SHOULD
HAVE A LULL THURSDAY MORNING BEFORE ANOTHER DISTURBANCE MOVES
THROUGH THURSDAY AFTERNOON BRINGING ANOTHER CHANCE FOR SHOWERS AND
THUNDERSTORMS. SMALL CHANCES FOR PRECIPITATION CONTINUE THURSDAY
NIGHT...AGAIN PRIMARILY ALONG AND NORTH OF THE INTERSTATE. HIGHS
ON THURSDAY AROUND 70 IN THE FAR NORTHWEST...LOW 80S ACROSS THE
FAR EAST-SOUTH.
FRIDAY THROUGH MONDAY...A LONGWAVE TROUGH WILL BE IN PLACE OVER THE
WESTERN CONUS THROUGH THE PERIOD...AND SEVERAL SHORTWAVE TROUGHS
WILL MOVE EASTWARD AND OVER THE REGION DURING THIS TIME. UPPER LEVEL
SUPPORT FROM THESE TROUGHS ALONG WITH LOW LEVEL SUPPORT FROM A
COUPLE OF FRONTS WILL LEAD TO A POSSIBILITY FOR SHOWERS AND
THUNDERSTORMS THROUGH MUCH OF THE PERIOD. A WARM FRONT WILL LIFT
NORTHWARD ON FRIDAY NIGHT/SATURDAY MORNING...AND THE HIGHEST CHANCE
FOR PRECIPITATION WILL BE IN THE NORTHERN PORTION OF THE AREA.
CONDITIONS WILL BE WINDY DURING THE AFTERNOON ON SATURDAY DUE TO A
SURFACE LOW DEEPENING OVER EASTERN COLORADO AND THE ASSOCIATED
STRENGTHENING OF THE PRESSURE GRADIENT. A COLD FRONT IS EXPECTED TO
MOVE INTO THE AREA FROM THE NORTHWEST ON SATURDAY NIGHT AND INTO
SUNDAY MORNING...WITH THE ECMWF MOVING THE FRONT FURTHER EASTWARD
THAN THE GFS. BOTH MODELS KEEP THE FRONT MOSTLY STATIONARY DURING
THE DAYTIME ON SUNDAY...THEN MOVE IT EASTWARD ON MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 230 AM MDT TUE MAY 22 2012
VFR EXPECTED AT BOTH KGLD AND KMCK. SOUTH WINDS WILL INCREASE
QUICKLY THIS MORNING WITH GUSTS UP TO 30 KTS OR SO AT KGLD AND 35
KTS AT KMCK AFTER 18Z. GUSTS WILL COME DOWN A BIT AFTER SUNSET
ALTHOUGH SUSTAINED WINDS OF 15-20 KTS EXPECTED THROUGH EARLY
WEDNESDAY MORNING BEFORE A COLD FRONT MOVES THROUGH KGLD CLOSE TO
12Z...SLIGHTLY LATER AT KMCK.
&&
.CLIMATE...
ISSUED AT 230 AM MDT TUE MAY 22 2012
RECORD HIGH TEMPERATURES FOR TODAY INCLUDE
GOODLAND.....97 (1939)
HILL CITY....96 (2004)
MCCOOK.......97 (1964)
BURLINGTON...95 (1939)
YUMA.........95
TRIBUNE......100
COLBY........98
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JRM
SHORT TERM...007
LONG TERM...007/CJS
AVIATION...007
CLIMATE...007
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1155 PM MDT MON MAY 21 2012
.UPDATE...
ISSUED AT 1139 PM MDT MON MAY 21 2012
WINDS HAVE STEADILY INCREASED DURING THE LAST COUPLE OF HOURS
ACROSS MOST OF THE AREA AS THE STRONG PRESSURE GRADIENT REMAINS IN
PLACE AND THE LOW LEVEL JET DEVELOPS. WINDS WILL BE STRONGEST
ALONG THE COLORADO BORDER WHERE THE WINDS FROM THE LOW LEVEL JET
WILL BE ABLE TO BETTER MAKE IT TO THE SURFACE. THE WINDS SHOULD
DECREASE SOME OVER THE WEST DURING THE OVERNIGHT HOURS AS THE LOW
LEVEL JET MOVES SLIGHTLY TO THE EAST.
OVER THE LAST FEW HOURS THE RUC HAS BACKED OFF ON FOG DEVELOPMENT
OVERNIGHT...AND THE NAM HAS BECOME EVEN DRIER THAN THE PREVIOUS
MODEL RUN. HOWEVER...WITH THE BREEZY SOUTH WINDS BRINGING HIGHER
DEW POINTS IN DURING THE NIGHT...WILL LEAVE IN THE MENTION OF
PATCHY FOG FOR ROUGHLY THE SOUTHERN HALF OF THE AREA.
UPDATED SOME OF THE FORECAST FOR TOMORROW...MAINLY FOR THE WINDS
OVER THE EASTERN PART OF THE AREA. INCREASED THE WINDS SOME BASED
OFF THE LATEST MIXED LAYER WINDS FROM THE NAM/SREF. STILL LOOKS
LIKE THE POTENTIAL IS THERE FOR CRITICAL FIRE WEATHER. HOWEVER THE
QUESTION IS IF THE WINDS AND LOW RHS WILL BE COLOCATED LONG ENOUGH
TO WARRANT A HIGHLIGHT. WILL LET THE MID SHIFT TAKE A LOOK AT THIS
AND HOLD OFF ISSUING ANY THING AT THIS TIME.
UPDATE ISSUED AT 822 PM MDT MON MAY 21 2012
INCREASED PRECIPITATION CHANCES OVER PART OF SOUTHWEST NEBRASKA AS
A THUNDERSTORM APPROACHES THE AREA. STORM SHOULD EXIT THE
SOUTHWEST NEBRASKA AND FAR NORTHWEST KANSAS AROUND MIDNIGHT ASSUMING IT
WILL AT CONTINUE AT ITS CURRENT RATE OF SPEED AND DIRECTION.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 121 PM MDT MON MAY 21 2012
16Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED BROAD RIDGING IN
PLACE ACROSS THE CENTRAL ROCKIES AND ADJACENT HIGH PLAINS...WITH
TROUGH APPROACHING THE PACIFIC NORTHWEST. AT THE SFC...TROUGH WAS IN
PLACE ACROSS CENTRAL AND EASTERN COLORADO ...ROUGHLY BETWEEN KDNR
AND KAKO. TO THE EAST OF THIS TROUGH...MOISTURE ADVECTION WAS
INCREASING WITH AN AREA OF DEW POINTS AT OR ABOVE 50 F FROM KLIC
SOUTHEAST INTO THE OKLAHOMA PANHANDLE. 12Z RAOBS AT DNR AND DDC
INDICATED AREA OF STEEP MID LEVEL LAPSE RATES BETWEEN H7 AND
H6...WITH A MUCH DEEPER LAYER NOTED AT DNR.
MAIN CONCERN FOR THE SHORT TERM PERIODS WILL BE CONVECTIVE
INITIATION CHANCES TODAY AND TEMPS/RH/FIRE WX TOMORROW.
REST OF THE AFTERNOON-TONIGHT...WITH AFOREMENTIONED MOISTURE
ADVECTION ALREADY ONGOING PER SFC OBS...AND NOSE OF STEEP MID LEVEL
LAPSE RATES IN PLACE ALONG SFC TROUGH ACROSS EASTERN COLORADO
CONFIDENCE INCREASING IN CONVECTIVE INITIATION ALONG SFC TROUGH THIS
AFTERNOON...ESPECIALLY GIVEN THAT MIXED LAYER TDS ARE VERY SIMILAR
TO FORECAST SFC VALUES INDICATING SOME DEPTH TO THE MOISTURE
PROFILE. WHILE CONFIDENCE IN DEVELOPMENT OF THUNDERSTORMS IS
HIGHER...HIGHER RES MODELS KEEPING COVERAGE FAIRLY SPARSE AND WITH
LATEST HRRR JUMPING AROUND QUITE A BIT WITH TIMING AND LOCATION...DO
NOT THINK POPS ABOVE THE 20-30 PERCENT RANGE WARRANTED JUST YET.
WITH A LOT OF UNCERTAINTY IN THE DETAILS...HAVE GENERALLY WENT WITH
BROADER COVERAGE OF POPS STARTING FIRST AROUND SFC TROUGH AROUND 20Z
AND GRADUALLY SHIFTING EAST AND DIMINISHING. SOME ELEVATED
INSTABILITY REMAINS THROUGH THE NIGHT WITH SOME WEAK ASCENT EXPECTED
TO THE WEST OF H7 THERMAL RIDGE. PROBABILISTIC GUIDANCE NOT REALLY
SUPPORTING MUCH OF A PRECIP THREAT AT THIS POINT...BUT CANNOT
TOTALLY RULE OUT SOME ELEVATED OVERNIGHT STORMS AND WILL GENERALLY
KEEP PREVIOUS FORECAST IN THIS REGARD. GIVEN ALREADY OBSERVED
MOISTURE TRANSPORT...DO HAVE SOME CONCERNS ABOUT THE DEVELOPMENT OF
FOG OVERNIGHT. WINDS SHOULD GENERALLY STAY UP WHICH WILL MINIMIZE
THE THREAT SOME WHAT...BUT GIVEN EXPECTED MOISTURE PROFILE AND SREF
INDICATING A SMALL THREAT FOR FOG THINK AT LEAST A PATCHY MENTION IS
IN ORDER.
TUESDAY...H5 RIDGE AXIS WILL SHIFT TO THE EAST THROUGH THE
DAY...WITH CWA UNDER THE INFLUENCE OF LARGE SCALE FORCING FOR
SUBSIDENCE THROUGH MUCH OF THE DAY. WHILE SYNOPTIC SCALE SUPPORT IS
LACKING...FAIRLY STRONG AND PERSISTENT CONVERGENCE EXPECTED ALONG
DRY LINE THAT WILL DEVELOP ACROSS AREA DURING THE AFTERNOON. COULD
POTENTIALLY SEE A STORM OR TWO DEVELOP IN THIS AREA...BUT GIVEN
LARGE SCALE PATTERN...POTENTIAL FOR A STRONG CAP AND VERY LOW
PROBABILITIES FROM THE NORMALLY WET SREF DATABASE...CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THUNDERSTORM THREAT AT THIS TIME. MIXED LAYER
TEMPS STILL SUPPORT TEMPS IN THE 90S ACROSS MUCH OF THE
AREA...ALTHOUGH THERE DOES APPEAR TO BE SOME DISCREPANCIES FOR HOW
WARM THINGS WILL GET WITH SREF INDICATING A RANGE BETWEEN 97 AND
AROUND 88 FOR GLD. GIVEN OVERALL PATTERN AND POTENTIAL TO BE ON MUCH
DRIER SIDE OF THE DRY LINE THINK WARMER SOLUTIONS THE WAY TO AND MADE
ONLY MINOR CHANGES TO GOING FORECAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM MDT MON MAY 21 2012
A COLD FRONT WILL DROP SOUTH TOWARDS OUR CWA TUESDAY NIGHT AS A
SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN PLAINS. WITH AIR MASS OVER
CWA GENERALLY STABILIZING TUESDAY EVENING THUNDERSTORM CHANCES
REMAIN MINIMAL AND WILL BE TIED MAINLY TO WHAT DEVELOPS DURING THE
AFTERNOON. MODEL DIFFERENCES IN THE TIMING/POSITION OF THE FRONT
WILL HAVE A LARGER IMPACT ON THE TEMPERATURE FORECAST WEDNESDAY WHEN
IT WILL STALL OVER THE CWA AND THEN LIFT NORTH AS A WARM FRONT.
ECMWF AND GFS TEND TO BE THE QUICKEST IN DEVELOPING A STRONG LEE
TROUGH OVER EASTERN COLORADO...PUSHING THE FRONT NORTH BY MIDDAY.
CURRENT HIGH TEMP FORECAST FOR WEDNESDAY REFLECTS A BLEND OF
SOLUTIONS WITH UPPER 90S OVER SW PART OF THE CWA...AND UPPER 70S IN
THE NORTHWEST. WERE THE FRONT TO LIFT QUICKER...MID-UPPER 90S COULD
BE EXPECTED ACROSS A MUCH LARGER PART OF THE CWA. WITH THE SURFACE
TROUGH EXPECTED TO BE OVER THE CWA BY MIDDAY...STRONGEST SURFACE
GRADIENT SHOULD REMAIN EAST...SO WINDS SHOULD REMAIN BELOW RED FLAG
CRITERIA.
LARGE SCALE TROUGH DEVELOPS OVER THE GREAT BASIN/NORTHERN ROCKIES BY
WEDNESDAY AFTERNOON...WITH A SERIES OF WEAK SHORTWAVE TROUGH MOVING
JUST NORTH AND WEST OF THE CWA THROUGH NEXT WEEKEND. THE FIRST
SHORTWAVE ARRIVES BY WEDNESDAY NIGHT...WITH THUNDERSTORMS POSSIBLY
INITIATING OVER NORTHEAST COLORADO. BEST CHANCES WILL BE ACROSS THE
NORTH AFTER MIDNIGHT WEDNESDAY NIGHT WHEN A COLD FRONT WILL MOVE
INTO SOUTHWEST NEBRASKA AND STALL. I HAVE LESS CONFIDENCE FURTHER
SOUTH AND EAST...HOWEVER WITH AT LEAST SOME GUIDANCE SHOWING
DEVELOPMENT TOWARDS THE I-70 CORRIDOR...I FELT COMFORTABLE KEEPING
SLIGHT CHANCE/CHANCE POPS IN PLACE.
BY THURSDAY THIS INITIAL SHORTWAVE WILL MOVE TO THE EAST WITH
SUBSIDENCE BUILDING IN OVER THE CWA IN IT WAKE. AT THE SAME TIME
ANOTHER WEAK DISTURBANCE WILL BE MOVING IN FROM THE WEST BY THURSDAY
AFTERNOON/NIGHT...WITH POPS INCREASING ONCE AGAIN FROM THE
WEST...AND CHANCES LIMITED TO NORTH OF INTERSTATE 70.
FRIDAY-MONDAY...LARGE SCALE TROUGH REMAINS IN PLACE ACROSS THE
WESTERN CONUS...EVENTUALLY BREAKING DOWN AND TRANSITIONING TO A
WESTERLY ZONAL PATTERN BY EARLY NEXT WEEK. RESULT WILL BE A FAIRLY
ACTIVE PATTERN...WITH STORM TRACK FAVORING NORTHERN PORTIONS OF OUR
CWA FOR SHOWER/THUNDERSTORM CHANCES. CONFIDENCE WAS TOO LOW TO RAISE
POPS BEYOND 20/30 RANGE...CONSIDERING DIFFERENCE IN TIMING OF THESE
FEATURES...AND DIFFERENCES IN POSITION OF SURFACE FEATURES AS
HANDLED BY GUIDANCE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1139 PM MDT MON MAY 21 2012
VFR CONDITIONS ARE FORECAST FOR THE 6Z TAFS. WINDS WILL REMAIN
BREEZY FOR KGLD OVERNIGHT AS A FAIRLY TIGHT PRESSURE GRADIENT REMAINS
IN PLACE OVER THE AREA. MODELS HAVE BACKED OFF THE POTENTIAL FOR
FOG...BUT WITH DEW POINTS SLOWLY CLIMBING THROUGH THE EVENING
WILL CONTINUE TO KEEP THE LOW VFR VIS IN TOWARD THE EARLY MORNING
HOURS FOR KGLD. ALSO KEPT IN THE MENTION OF LOW CLOUDS AT BOTH SITES
AS SOUNDINGS AND CROSS SECTIONS BOTH SHOW THE POTENTIAL FOR CLOUDS
TO DEVELOP IN THE IFR RANGE...ALTHOUGH NOT ENOUGH TO WARRANT AN
IFR CEILING GROUP. WINDS WILL STRENGHTEN SOME DURING THE
MORNING...POTENTIALLY INCREASING FURTHER DURING THE AFTERNOON AND
INTO THE EVENING.
&&
.FIRE WEATHER...
ISSUED AT 121 PM MDT MON MAY 21 2012
VERY WARM AND DRY WEATHER IS EXPECTED ACROSS MUCH OF THE AREA ON
TUESDAY...WITH AFTERNOON HUMIDITIES BELOW 15 PERCENT EXPECTED
ALONG AND EAST OF THE COLORADO AND KANSAS STATE LINE. WESTERLY
WINDS WILL GRADUALLY INCREASE IN THIS AREA TO AROUND 15 MPH IN THE
AFTERNOON. WITH RECENT RAINFALL AND WINDS NOT EXPECTED TO INCREASE
TO LATE IN THE AFTERNOON...OVERALL CONFIDENCE IN CRITICAL FIRE
WEATHER CONDITIONS IS TOO LOW TO WARRANT A WATCH OR WARNING AT
THIS POINT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...JRM
LONG TERM...DR
AVIATION...JTL
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS GRAY ME
334 PM EDT TUE MAY 22 2012
.SYNOPSIS...
LOW PRESSURE TO OUR SOUTH WILL PASS EAST OF THE AREA OVERNIGHT. A
COLD FRONT WILL MOVE INTO NORTHERN NEW ENGLAND BY TOMORROW MORNING
AND OFFSHORE LATE TOMORROW. WEAK HIGH PRESSURE WILL MOVE INTO THE
AREA THURSDAY AND FRIDAY WITH A CHANCE OF SHOWERS MAINLY INLAND. A
WARM AND DRY SATURDAY IS ON TAP AS HIGH PRESSURE CRESTS OVER NEW
ENGLAND...THEN A COLD FRONT IS EXPECTED TO SAG FROM WEST TO EAST OVER
NEW ENGLAND SUNDAY AND MONDAY. THE FRONT IS EXPECTED TO PUSH
NORTHWARD THROUGH THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A LOW PRESSURE SYSTEM WAS CENTERED NEAR CAPE COD THIS AFTERNOON
WITH A WARM FRONT ARCING INTO SOUTHERN NH AND MAINE. MOISTURE
CONTINUED TO FLOW NORTH INTO THE AREA. AT THE SAME TIME A COLD
FRONT WAS MOVING SLOWLY THROUGH SOUTHERN QUEBEC...NEW YORK...AND
PENNSYLVANIA.
AT THE MOMENT MOST OF THE HEAVIER SHOWERS WERE LOCATED OVER THE
HIGHER TERRAIN OF NORTHERN COOS...FRANKLIN...OXFORD...AND
SOMERSET. THE HRRR AND NAM12 INDICATE A BREAK OVER MUCH OF THE
AREA TONIGHT EXCEPT FOR PERHAPS SOUTHERN NH AND SOUTHWEST MAINE
WHERE MOISTURE CONVERGENCE IS BEST. STILL...EXPECT DRIZZLE AND
WIDESPREAD FOG FOR MUCH OF THE REGION. AS THE COLD FRONT MOVES
INTO THE NH MOUNTAINS AND WESTERN MAINE OVERNIGHT...SHOWERS WILL
BECOME MORE WIDESPREAD. THERE IS SOME ELEVATED INSTABILITY BUT
FELT THERE WAS NOT ENOUGH TO INCLUDE THUNDERSTORMS IN THE
FORECAST. OVERNIGHT LOWS WILL BE IN THE MID 50S.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
LINE OF SHOWERS WILL WORK SLOWLY SOUTHEAST TOMORROW WITH THE COLD
FRONT ALONG WITH ISOLATED THUNDERSTORMS. QPF AMOUNTS WILL
GENERALLY BE LIGHT HOWEVER ANY CONVECTION WILL BOOST RAINFALL
TOTALS. WE WILL SEE CLEARING AND EVENTUALLY PARTLY SUNNY SKIES
WORK IN FROM THE NORTH BY THE AFTERNOON. THIS WILL CONTRIBUTE TO
HIGH TEMPERATURES IN THE 70S.
THE BOUNDARY ESSENTIALLY STALLS AND BY WASHES OUT BY EVENING AS
THE LOW PRESSURE TO OUR EAST PULLS AWAY AND WE LOSE ANY UPPER
LEVEL PUSH. THIS WILL ENSURE MOISTURE HANGS AROUND IN THE LOW
LEVELS. ONCE THE RAIN ENDS FOG WILL DEVELOP AND BECOME DENSE AFTER
DARK. WEDNESDAY NIGHT`S LOWS WILL BE IN THE LOWER 50S NORTH TO
UPPER 50S SOUTH WITH NEGLIGIBLE TEMPERATURE ADVECTION.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...MEDIUM RANGE MODELS ARE IN
FAIR AGREEMENT IN THE GENERAL PATTERN. WEAK SURFACE HIGH PRESSURE
WILL REMAIN OVER THE AREA THURSDAY AND FRIDAY...BUT SHORTWAVES
ALOFT MOVING THROUGH NEW ENGLAND WILL KEEP A CHANCE OF SHOWERS
EACH DAY...MAINLY INLAND. ON SATURDAY THE RIDGE OVER THE
SOUTHEASTERN UNITED STATES SURGES NORTHWARD INTO NEW ENGLAND FOR A
VERY WARM DAY...WITH SOME LOCATIONS IN NEW HAMPSHIRE POSSIBLY
TOUCHING 90 DEGREES. THEN A WEST-EAST-ORIENTED COLD FRONT WILL SAG
SOUTHWARD ACROSS THE AREA SUNDAY THROUGH TUESDAY. POSITION AND
STRENGTH OF THIS BOUNDARY ARE UNCERTAIN AT THIS TIME. CAN`T RULE
OUT A CHANCE OF AFTERNOON THUNDERSTORMS AND SHOWERS EACH DAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHORT TERM...MOSTLY VFR CONDITIONS AT THE MOMENT WITH A BREAK IN
PRECIPITATION FOR MOST TERMINALS UNTIL THE EVENING. THE EXCEPTION
WILL BE PORTSMOUTH WHICH STAYS IN AN AREA OF CONVERGENCE. DRIZZLE
AND FOG WILL RETURN AROUND 00Z CAUSING CEILINGS AND VISIBILITIES
TO DROP AGAIN TO IFR/LIFR CATEGORIES. A COLD FRONT WILL MOVE IN
FROM THE WEST TONIGHT WITH RAIN CHANCES INCREASING FROM NW TO SE
THROUGH TOMORROW.
LONG TERM...OCCASIONAL MVFR CONDITIONS IN SCATTERED SHOWERS
THURSDAY AND FRIDAY. VFR SATURDAY THEN POSSIBLE MVFR IN
ANY THUNDERSTORMS SUNDAY.
&&
.MARINE...
SHORT TERM...HAVE ISSUED A SCA FOR HIGH SEAS BEGINNING TONIGHT AND
ENDING TOMORROW EVENING AS LOW PRESSURE PASSES TO THE EAST.
LONG TERM...NO SIGNIFICANT FEATURES DURING THE PERIOD.
&&
.FIRE WEATHER...
SCATTERED SHOWERS AND HIGH RELATIVE HUMIDITIES WILL LAST THROUGH
FRIDAY WITH A COLD FRONTAL PASSAGE AND MORE SUBSTANTIAL RAINS
SATURDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 PM THIS EVENING
TO 8 PM EDT WEDNESDAY FOR ANZ150-152-154.
&&
$$
HANES/ST.JEAN
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
234 AM EDT TUE MAY 22 2012
.SYNOPSIS...
LOW PRESSURE AND UNSETTLED CONDITIONS WILL PERSIST ACROSS THE AREA
THROUGH MID WEEK. HIGH PRESSURE BUILDS INTO THE AREA LATE THIS WEEK
INTO THE HOLIDAY WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE TO ADD 30 PERCENT CHC SHOWERS/ISOLATED THUNDER MOST AREAS
WEST OF THE CHESAPEAKE. HRRR AND OTHER HIGH RES MODELS INDICATE
CONVECTION OVERNIGHT IN AN AREA THAT HAS SLIGHTLY NEGATIVE LI/S.
AS OF 03Z...SHOWERS WERE OVER BRUNSWICK COUNTY AND APPROACHING
LUNENBURG AND MECKLENBURG COUNTY FROM THE WEST. LEFT SLGT CHC
SHOWERS ERN PORTIONS WHERE THE ATMPOSPHERE IS RELATIVELY STABLE.
PREVIOUS DISCUSSION...
MOST PCPN HAS WEAKENED / DISSIPATED SINCE SUNSET WITH ONLY A FEW
SHOWERS OVER I95 CORRIDOR NORTH OF RICHMOND. NOW WATCHING BAND OF
SHOWERS / TSTRMS FROM LYH-DAN. TUFF CALL ON JUST HOW FAR EAST THEY
GET NEXT FEW HOURS AS SHORT RANGE MODELS DIFFER A BIT ON HOW LONG
THEY SURVIVE. THUS...HAVE ADDED ISLTD THUNDER TO EXTREME WESTERN
COUNTIES NEXT FEW HOURS FOR ANY CELL THAT DOES MOVE EAST. OTW...ENUF
MOISTURE IN PLACE FOR AT LESAT ISOLATED SHOWERS FOR THE REST OF THE
NIGHT...ESPECIALLY ACROSS WESTERN HALF OF FA DUE TO LINGERING TROF.
ADDED PATCHY FOG ALONG THE EASTERN SHORE. LATER UPDATES MAY HAVE TO
EXPAND THE FOG THREAT TOWARD SUNRISE. WARM AND HUMID. LOWS 60-65.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
UNSETTLED CONDS...NOT DUE TO TS ALBERTO...WILL CONTINUE THRU THE
SHORT TERM PERIOD WITH THE AFOREMENTIONED UPR-LVL TROF STILL IN
PLACE ALONG THE EASTERN SEABOARD. THIS WILL LEAD TO PERIODIC
CHANCES FOR SHOWERS AND STORMS AS MOIST S/SW FLOW CONTINUES. FOR
TUE...SFC TROF WILL BE SITUATED OVR WESTERN PORTIONS OF THE FA
WHERE HIGHEST POPS (50%) WERE PLACED...30-40% ELSEWHERE. TEMPS
CLIMB INTO THE UPR 70S TO LWR 80S UNDER A MSTLY CLDY SKY. RAIN MAY
LINGER INTO TUE NGT...WITH THE BEST CHC AGAIN OVR WESTERN AREAS.
UPR-LVL TROF CUTS OFF FROM THE MEAN FLOW TUE NGT INTO WED AS A
POTENT S/W DIVES DOWN THE TROF BASE. THE CENTER OF THE RESULTING
UPR-LVL LOW WILL CENTER ITSELF NEAR THE MID ATLANTIC WED INTO
THU...WITH CHANCES FOR RAIN EACH DAY. BEST CHANCE FOR RAIN DURING
THE PERIOD WILL BE WED (LIKELY POPS FOR NW QUADRANT OF FA) WITH A
SFC TROF OVR THE MID ATLANTIC...DECENT FORCING ALOFT...AND A VERY
MOIST ATM. SEASONABLE TEMPS CONTINUE WED AND THU...HIGHS STILL IN
THE UPR 70S TO LWR 80S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE LATEST NUMERICAL GUIDANCE IS SUGGESTING THAT THE PERSISTENT
UPPER LOW MAY LINGER INTO FRIDAY. HOWEVER...AT THIS POINT NOTHING
MORE THAT A SLIGHT CHANCE POP IS NECESSARY. AN UPPER HIGH THEN
BUILDS OVER THE OHIO VALLEY FOR THE MEMORIAL DAY WEEKEND. GIVEN
WHERE THE HIGH SETS UP IT IS POSSIBLE SOME CONVECTION COULD ROUND
THE TOP OF THE RIDGE AND APPROACH THE LOCAL AREA IN MID-LEVEL NNW
FLOW. THE LARGE MAJORITY OF THE TIME IS EXPECTED TO BE DRY AND THERE
IS BASICALLY NO SKILL IN FORECASTING MCS ACTIVITY IN THE MEDIUM
RANGE. TEMPERATURES SHOULD BE ABOVE SEASONAL AVERAGES WITH HIGHS IN
THE MID 80S TO NEAR 90 (SLIGHTLY COOLER ALONG THE COASTS WITH LIGHT
ONSHORE FLOW). LOW TEMPERATURES SHOULD GENERALLY BE IN THE 60S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS AT MOST TERMINALS AS OF 06Z...WITH THE EXCEPTION OF
SOME MVFR/TEMPO IFR CONDS AT KSBY/KECG. WEAK LOW PRESSURE PERSISTS OVER
THE REGION WITH MOSTLY LIGHT WINDS FROM THE E-SE. BIGGEST CONCERN
EARLY THIS MORNING IS W/THE CHANCE OF MORE WIDESPREAD IFR
CONDITIONS DUE TO PLENTY OF LOW LEVEL MOISTURE. ACCORDINGLY HAVE
GONE WITH LOWERING CIGS TO LOW MVFR/IFR RANGE AT RIC/ORF/PHF TOWARDS
DAWN. HAVE ALSO ALLOWED FOR SOME PATCHY DENSE FOG AT ALL SITES
AFTER 08Z THROUGH JUST AFTER SR.
VFR CONDITIONS ARE EXPECTED BY MID TO LATE MORNING AS WINDS SHIFT
TO THE S-SW DURING THE LATE NIGHT TUESDAY AND OVERNIGHT HOURS WED
MORNING. MORE SHOWERS AND TSTMS POSSIBLE FOR TUE AFTN/EVENING
AFTER 18-20Z THROUGH EARLY EVENING AS WEAK INSTABILITY CONTINUES
OVER THE REGION, COURTESY OF APPROACHING UPPER TROUGH FROM THE
WEST.
OUTLOOK...SLOW MOVING UPPER SYSTEM WILL RESULT IN CONTINUED
UNSETTLED WEATHER WED AND THU...WITH THE POTENTIAL FOR FLIGHT
RESTRICTIONS IN PATCHY FOG EACH MORNING AND IN SCT CONVECTION EACH
AFTN. CLEARING FINALLY BUILDS IN FROM THE WEST FOR FRIDAY AND INTO
THE UPCOMING HOLIDAY WEEKEND.
&&
.MARINE...
THE LATEST SURFACE ANALYSIS SHOWS A RATHER NEBULOUS SURFACE PATTERN
ACROSS THE LOCAL MARNIE AREA AND HENCE WEAK FLOW. THIS GENERAL FLOW
PATTERN SHOULD CONTINUE THROUGH MUCH OF THE WEEK WITH S OR SE FLOW
AOB 10KT. AN AREA OF LOW PRESSURE (NOT TS ALBERTO) PRESENTLY WELL
EAST OF THE NC COAST WILL MOVE NNE ON A TRAJECTORY TOWARD NS THROUGH
TUESDAY. WNA WAVE SHOWS SWELL ASSOCIATED WITH THIS LOW AFFECTING THE
MARINE AREA TUESDAY INTO TUESDAY NIGHT WITH SEAS AOA 5FT GENERALLY
OUT PAST 5-10NM. AN SCA FOR HAZARDOUS SEAS WILL BE RAISED FROM 6AM
TUESDAY TO 6AM WEDNESDAY. OTHERWISE...SEAS SHOULD DROP BELOW SCA FOR
THE REMAINDER OF THE WEEK. UNSETTLED CONDITIONS SHOULD PERSIST MUCH
OF THE WEEK WITH A CHANCE FOR MAINLY AFTERNOON AND EVENING
THUNDERSTORMS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 AM THIS MORNING
TO 6 AM EDT WEDNESDAY FOR ANZ650-652-654-656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MPR/LSA
SHORT TERM...MAS
LONG TERM...AJZ
AVIATION...MAM
MARINE...AJZ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
744 PM EDT WED MAY 23 2012
.SYNOPSIS...
ISSUED AT 427 PM EDT WED MAY 23 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
OVER THE NW CONUS AND A RIDGE FROM THE CNTRL GREAT LAKES INTO NRN
ONTARIO RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE UPPER MS
VALLEY AND LAKE SUPERIOR. AT THE SFC...SRLY WINDS WERE INCREASING
ACROSS THE REGION AHEAD A COLD FRONT EXTENDING THROUGH THE ERN
DAKOTAS FROM LOW PRESSURE OVER SRN MANITOBA. AN AREA OF TSRA WAS
MOVING NE THROUGH N CNTRL MN SUPPORTED A SHRTWV NEAR THE NOSE OS
STRONG 925-850 MB THETA-E ADVECTION. OVER UPPER MI...VIS LOOP AND
SFC OBS SHOWED CONSIDERABLE HIGH CLOUDS IN THE BROAD WAA PATTERN
AHEAD OF THE FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
TONIGHT...AS A SHRTWV OVER NW MN LIFTS TO THE NE AND
THE NEXT SIGNIFICANT UPSTREAM SHRTWV OVER NEVADA ROTATES THROUGH
THE WRN TROF...ANOTHER SFC LOW WILL DEVELOP IN THE PLAINS AND
MOVE NNEWD ON COLD FNT ATTENDANT TO FIRST SFC LO DRIFTING THRU NW
ONTARIO. EXPECT THAT THE GREATEST CHANCE FOR SHRA/TSRA WILL REMAIN
CLOSER TO THE FRONT AND NEAR THE AXIS OF GREATER
MOISTURE/INSTABILITY OVER MN AND FAVORABLE UPPER LEVEL DIV WITH THE
RIGHT ENTRANCE OF THE JET OVER NW ONTARIO. SO...THE NAM/REGIONAL
GEM/ECMWF WERE PREFERRED WITH THE SHRA/TSRA PLACEMENT COMPARED TO
THE GFS WHICH SEEMED OVERLY AGGRESSIVE IN PUSHING THE PCPN TO THE
EAST.
THURSDAY...THE MAIN SHRTWV LIFTS OUT OF THE PLAINS TO THE UPPER MS
VALLEY SUPPORTING A CONSOLIDATED SFC LOW TO NEAR KDLH BY 00Z/FRI.
GIVEN THE STRENGTHENING DYNAMICS AGAIN TO THE WEST...CONTINUED TO
DELAY THE EASTWARD PROGRESSION OF THE SHRA/TSRA INTO UPPER MI TIL
MAINLY LATE IN THE DAY. MLCAPE VALUES TO AROUND 1K J/KG WITH
AFTERNOON HEATING AND SFC DEWPOINTS NEAR 60 WILL SUPPORT TSRA
CHANCES FROM IWD-CMX...MAINLY AFT 21Z. WITH INVERTED V LOOK TO THE
SOUNDINGS AND VERY STRONG MAINLY UNIDIRECTIONAL WIND FIELD (700 MB
WINDS TO NEAR 70KT)...EXPECT THAT DAMAGING WINDS WILL BE THE MAIN
HAZARD WITH ANY TSRA.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
MAIN CONCERN FOR THE LONG TERM PERIOD IS THE SEVERE WEATHER
POTENTIAL AT THE BEGINNING OF THE PERIOD.
STATIONARY FRONT WILL BE SETUP OVER WRN LK SUPERIOR...WHILE A FAIRLY
POTENT SHORTWAVE PUSHING NE ACROSS AT LEAST THE WRN HALF OF THE CWA
THURS NIGHT. THIS WILL LEAD TO ONGOING CYCLOGENESIS OVER NW WI
DURING THE LATE AFTERNOON AND THE LOW MOVING NNE ACROSS WRN LK
SUPERIOR DURING THE EVENING. EXPECT THUNDERSTORMS TO BE ONGOING
OVER NW WI AND FAR WRN LK SUPERIOR AT THE START OF THE PERIOD AND
THEN MOVE E AND NE AS THE COLD FRONT PUSHES THROUGH THE CWA DURING
THE NIGHT.
WITH THE STRONG WINDS ALOFT AND THE CYCLOGENESIS...FEEL THAT THERE
IS A DECENT CHANCE OF SEVERE WEATHER OVER THE WRN HALF OF THE CWA
TOMORROW EVENING. THERE IS A VERY THIN CORRIDOR OF MLCAPE VALUES
APPROACHING 500-1000 J/KG OVER THE WRN THIRD OF THE CWA AND
INSTABILITY MAY BE THE MAIN LIMITING FACTOR AS STORMS MOVE INTO THE
CWA. CAPE FAIRLY SKINNY...NCAPE VALUES AROUND 0.1...SO DON/T EXPECT
MUCH MORE THAN MARGINALLY SEVERE HAIL.
WIND APPEARS TO BE BIGGEST THREAT WITH THE STORMS. INVERTED V LOOK
TO THE SOUNDINGS OVER THE WEST AND DCAPE VALUES OF 600-800 J/KG.
STRONG WINDS ALOFT...APPROACHING 70-80KTS AT H700 AND
40-50KTS JUST A COUPLE HUNDRED FEET ABOVE THE SFC...WILL BE
AIDED BY A POCKET OF DRY H700-500 AIR AND STEEPER LAPSE RATES.
THIS...COMBINED WITH STORM MOTION TO THE NNE AT 65-70KTS ALL POINT
TO THE POTENTIAL FOR DAMAGING WINDS WHERE THUNDERSTORMS...AND
POTENTIALLY EVEN SHOWERS OCCUR. WITH THE LOW DEVELOPING ALONG THE
FRONT POTENTIALLY AFFECTING THE LLVL WIND FIELD...COULD SEE SOME
LLVL BACKING OF THE WINDS AND PRODUCE SOME ROTATING UPDRAFTS AND
SUPERCELLS...ESPECIALLY OVER NW WI. BUT THE EXPECTED DRY LLVL AIR
HELPING PRODUCE AN INVERTED V AND LCL HEIGHTS TOWARDS 3-3.5KFT
SHOULD LIMIT TORNADO POTENTIAL THIS FAR N.
CURRENT THOUGHT IS BEST CHANCES FOR SEVERE SHOULD BE FROM
BARAGA/IRON COUNTIES AND WEST...BUT WITH THE STORM MOTIONS...COULD
POTENTIALLY AFFECT MARQUETTE/DICKINSON/MENOMINEE COUNTIES BEFORE
HEADING OVER LK SUPERIOR. ADDED DAMAGING WIND THREAT TO THE GRIDS
AND MENTIONED IN THE HWO. THIS MATCHES UP WELL WHERE SPC HAS A
SLIGHT RISK...WITH HATCHED AREA JUST TO THE SW OF THE CWA.
AS THE LOW QUICKLY LIFTS NE...EXPECT BEST FORCING TO QUICKLY
DEPART OVERNIGHT AND PULL FORCING WITH IT. IN ADDITION...AS THE COLD
FRONT PUSHES EAST INTO THE CNTRL/ERN CWA...THE CAPPING BECOMES
STRONGER. WITH THE COMBINATION OF LOOSING FORCING AND MORE
UNFAVORABLE ENVIRONMENT...EXPECT THE SHOWERS/THUNDERSTORMS TO
DIMINISH AS THEY MOVE INTO THE CNTRL/ERN CWA. 09Z SREF ALSO SHOWING
THIS DIMINISHING TREND IN THE 3HR CALIBRATED THUNDERSTORM PROBS...AS
THE SHOWERS/THUNDERSTORMS PUSH TO THE NE OVER LK SUPERIOR DURING THE
OVERNIGHT HOURS.
EXPECT GUSTY SE WINDS IN THE EVENING AHEAD OF THE LOW AND OVER THE
KEWEENAW OVERNIGHT BEHIND THE LOW/FRONT. BUMPED UP WINDS
SIGNIFICANTLY OVER THE KEWEENAW BEHIND THE LOW AND FRONT...WITH THE
STRONG WINDS JUST ABOVE THE SFC /NAM SHOWING 60KTS AT 1.5KFT/. IN
ADDITION...GOOD ISALLOBARIC COMPONENT TO THE WINDS OVER THE WEST
OVERNIGHT WITH THE INTENSIFYING LOW PUSHING NE. ONLY CONCERN FOR
GOING MORE THAN 30-35KTS AT THIS POINT IS AFFECT OF COOLER WATER
TEMPS...BUT THAT MAY NOT HAVE MUCH EFFECT OVER THE HIGHER TERRAIN.
FRI...GUSTY WRLY WINDS...30-35KTS...IN THE MORNING BEHIND THE LOW.
DRIER AIR MOVING IN AND H700 CAP SHOULD LIMIT DEVELOPMENT EVEN WITH
WEAK MID-LVL WAVE MOVING THROUGH. DEEP MOISTURE IS LIMITED AND ML/MU
CAPE VALUES ARE BELOW 100 JKG WOULD LEAD TO LITTLE/NO PCPN CHANCES.
LATEST NAM RUN HAS BACKED OFF ON PCPN AND WILL FOLLOW SUIT WITH
REMOVING SLIGHT CHANCES. WILL KEEP SKIES PARTLY/MOSTLY CLOUDY DURING
THE AFTN WITH EXPECTED DIURNAL CU DEVELOPMENT.
MIXING TO H750 WOULD YIELD HIGHS IN THE 70S...WITH THE HIGHEST
VALUES IN THE FAVORED DOWNSLOPE AREAS OF THE CNTRL. WITH THE GUSTY
WINDS AND DEEPER MIXING INTO THE LIMITED MOISTURE ALOFT...EXPECT RH
VALUES TO FALL TO 30 PERCENT. FIRE WX CONCERNS MAINLY OVER THE
CNTRL...WHERE LESS RAIN IS EXPECTED ON THURS NIGHT.
FRI NIGHT...WEAK HIGH PRESSURE RIDGE FROM HIGH JUST N OF MN. SFC LOW
DEVELOPING IN THE CNTRL PLAINS IN RESPONSE TO DEEP UPPER TROUGH
OVER THE WRN CONUS WILL BEGIN TO PUSH A WARM FRONT N TOWARDS THE
UPPER GREAT LAKES LATE FRI NIGHT. COULD PRODUCE A FEW SHOWERS
TOWARDS THE WI BORDER LATE.
CWA WILL BE ON THE E SIDE OF THE UPPER RIDGE AXIS STRETCHING FROM
THE OHIO VALLEY TO LK WINNIPEG UNTIL SUN NIGHT. STILL SEVERAL WEAK
DISTURBANCES PUSHING THROUGH THE FLOW SAT AFTN THROUGH SUN NIGHT.
THE WARM FRONT WILL CONTINUE TO SLOWLY PUSH NE ON SAT...AS IT
BATTLES THE HIGH THAT WILL HAVE MOVED EAST OVER ONTARIO. PCPN
CHANCES ON SAT WILL LARGELY DEPEND ON HOW FAR N THE FRONT WILL PUSH.
BEST CHANCES LOOK TO BE ON SAT NIGHT INTO SUN...AS THE FRONT MOVES
INTO NRN WI AND FINALLY INTO UPPER MI BY SUN AFTN. THIS WILL PUT THE
BEST WAA FOCUS OVER THE CWA. THERE ARE DECENT MID LEVEL LAPSE
RATES...BUT ELEVATED CAPES ARE NOT TOO IMPRESSIVE...SO HAVE CAPPED
THUNDER TO CHANCES FOR SAT NIGHT INTO SUN. WITH THE CONVECTION
LIKELY TO BE ELEVATED...THE MAIN THREAT WOULD BE SMALL HAIL AND
HEAVY RAIN.
CWA WILL BE UNDER THE WARM SECTOR LATE SUN AFTN AND INTO SUN
NIGHT...WITH MODELS DIVERGING WITH THE HANDLING OF THE LOW HEADING
INTO THE FIRST PART OF NEXT WEEK. 12Z GFS SHOWS THE LOW CONTINUING
NNE INTO SRN CANADA ON SUN NIGHT AND MONDAY WHILE PUSHING COLD FRONT
ACROSS UPPER MI ON MON. 00Z ECMWF ON THE OTHERHAND DISSIPATES THE
LOW OVER THE CWA AND THEN SLOWLY SLIDES IT EAST THROUGH TUES. AFTER
A MORE ACTIVE PERIOD...OVERALL TREND LOOKS TO BE TOWARDS A SLIGHTLY
DRIER/QUIET WEATHER TOWARDS THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 743 PM EDT WED MAY 23 2012
STRONG WINDS AND LLWS WILL BE A CONCERN WHILE VFR CONDITIONS
DOMINATE THROUGHOUT THE FORECAST PERIOD. EXPECT CONDITIONS TO
DECOUPLE SOMEWHAT TONIGHT AS STRONG LOW-LEVEL WINDS DEVELOP. LLWS
WILL BE STRONG BUT GENERALLY UNIDIRECTIONAL...WITH WIND SPEEDS
1-2KFT AGL POSSIBLY REACHING 55-60KTS AFTER MIDNIGHT. LOW-LEVEL WIND
FIELDS STAY STRONG THROUGH THE DAY ON THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. ON THURSDAY...DECENT DAYTIME HEATING WILL
ALLOW STRONG WINDS TO MIX TO THE SURFACE. CURRENTLY HAVE IWD AND SAW
WITH GUSTS AROUND 30KTS...BUT WOULD NOT BE SURPRISED TO SEE SOME
GUSTS UP TO 40KTS LATE IN THE AFTERNOON WITH 50-60KT WINDS AROUND
3KFT. THUNDERSTORMS BEGIN TO AFFECT IWD AND CMX BY 00Z FRIDAY.
CURRENT EXPECTATION IS A STRONG TO SEVERE LINE OF THUNDERSTORMS
AHEAD OF THE COLD FRONT...WITH DAMAGING WINDS POSSIBLE. CONFIDENCE
OF STORMS OCCURRING IS HIGH...BUT CONFIDENCE IN TIMING IS LOW...SO
JUST GAVE A GENERAL TIMING IN THE TAF.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT WED MAY 23 2012
LOW PRESSURE OVER S MANITOBA WILL PUSH INTO ONTARIO TONIGHT AND
THURSDAY...AS AN ADDITIONAL LOW MOVES FROM THE CENTRAL PLAINS TO W
LS FRIDAY AFTERNOON. EXPECT THE LOW TO CONTINUE A NE TRACK ACROSS
ONTARIO THROUGH FRIDAY...WITH A TROUGH LINGERING ACROSS LAKE
SUPERIOR. STRENGTHENING S WINDS WILL PREVAIL AHEAD OF THIS SYSTEM
TONIGHT THROUGH THURSDAY. WITH A STABLE TEMPERATURE PROFILE THE
STRONGEST WINDS...EXPECT THE STRONGEST ACROSS THE TALLER OBSERVING
PLATFORMS ACROSS CENTRAL LAKE SUPERIOR.
HIGH PRESSURE OVER CENTRAL CANADA FRIDAY NIGHT WILL SLIDE ACROSS
ONTARIO SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON SUNDAY. AS A
RESULT...A RIDGE WILL SLIDE ACROSS LS SATURDAY...WITH LIGHTER WINDS
TAKING HOLD. A LOW ACROSS THE CENTRAL PLAINS WILL FILL ACROSS MN
SUNDAY INTO SUNDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...TK
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
433 PM EDT TUE MAY 22 2012
.SYNOPSIS...
ISSUED AT 430 PM EDT TUE MAY 22 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
THE GULF OF ALASKA INTO THE NW CONUS AND A FLAT DOWNSTREAM RIDGE
FROM THE SRN PLAINS TO THE UPPER MS VALLEY RESULTING IN WRLY FLOW
THROUGH THE NRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDED FROM
JAMES BAY THROUGH ERN LAKE SUPERIOR AND LAKE MI INTO THE MID MS
VALLEY. SRLY WINDS WERE INCREASING FROM THE PLAINS INTO MN AHEAD OF
LOW PRES OVER THE WRN DAKOTAS. RADAR AND SFC OBS INDICATED AN AREA
OF MAINLY VIRGA/-SHRA/SPRINKLES OVER WRN UPPER MI SUPPORTED BY
305K-310K ISENTROPIC LIFT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 430 PM EDT TUE MAY 22 2012
TONIGHT...EXPECT THAT THE -SHRA/SPRINKLES WILL CONTINUE TO DIMINISH
AS THEY MOVE TO THE EAST LATE THIS AFTERNOON AND EVENING. WITH THE
INCREASED CLOUD COVER AND SOUTHERLY WINDS TONIGHT...TEMPS WILL ONLY
DROP OFF INTO THE MID 40S INLAND AND LOWER TO MID 50S FOR DOWNSLOPE
LOCATIONS OVER THE WEST HALF.
WEDNESDAY...AS THE HIGH OVER THE LAKE AND THE PLAINS TROUGH SHIFTS
TO THE EAST...THE GRADIENT WILL INCREASE ACROSS UPPER MICHIGAN.
THE MODELS WERE IN GOOD AGREEMENT IN KEEPING THE MOISTURE/LIFT AHEAD
OF THE MID LEVEL AND SFC TROUGH TO THE WEST...GRADUALLY SHIFTING
INTO WRN LAKE SUPERIOR LATE. WITH THE WAA AND SUNSHINE...TEMPS
SHOULD CLIMB INTO THE MID AND UPPER 70S INLAND WITH COOLER READINGS
NEAR LAKE MICHIGAN. MIXING SHOULD ALSO ALSO A DECENT PORTION OF THE
25-30 KT SRLY 925 MB WINDS TO MIX TO THE SFC. INCREASED WILDFIRE
DANGER IS EXPECTED WITH THE COMBINATION OF 15 TO 20 MPH SFC WINDS
AND GUSTS TO 30 MPH ALONG WITH RH VALUES DROPPING TO AROUND 30
PERCENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 430 PM EDT TUE MAY 22 2012
THE PERIOD STARTS 00Z THU WITH A 500MB RIDGE OVER THE E COAST AND
LOWER GREAT LAKES...AND A 500MB TROUGH OVER FROM HUDSON BAY TO SRN
SASK TO THE CENTRAL ROCKIES. THIS PUTS THE CWA UNDER SW FLOW ALOFT.
AT THE SFC...A 994MB LOW WILL BE OVER FAR WRN ONTARIO...WITH A
TROUGH/COLD FRONT EXTENDING SW TO A 986MB LOW OVER ERN CO/WRN KS.
SFC HIGH PRESSURE OVER THE ERN SEABOARD COMBINED WITH LOW PRESSURE
TO OUR W WILL MAKE FOR GUSTY SLY WINDS...WITH 850MB WINDS OF 35-50KTS.
MOST OF THE MOISTURE OVER THE CWA WILL EXIST OVER FAR WRN LAKE
SUPERIOR AT 00Z THU...WITH 1000-500MB RH AROUND 30 PERCENT OVER
CENTRAL UPPER MI. 850MB TEMPS AROUND 18C AT 00Z THU WILL MAKE FOR
WARMER THAN NORMAL TEMPS. CONVECTION SHOULD BE ONGOING OVER WRN LAKE
SUPERIOR AS LOW LEVEL WARM AIR/MOISTURE ADVECTION NOSES INTO THE
VERY MOIST AIRMASS.
BY 12Z THU...THE ONTARIO SFC LOW WILL HAVE MOVED TO JAMES
BAY...WHILE THE CO/KS LOW WILL HAVE BECOME AN ELONGATED LOW FROM KS
TO CENTRAL MN AS AN UPPER SHORTWAVE TROUGH MOVES TO CENTRAL NE.
PRECIP WED NIGHT SHOULD CONTINUE OVER WRN LAKE SUPERIOR AS LOW LEVEL
WARM AIR/MOISTURE ADVECTION CONTINUES TO BE FOCUSED OVER THIS AREA.
WARM AIR ADVECTION DOES LOOK TO SPREAD ACROSS MOST OF THE CWA...BUT
WITH VERY DRY AIR OVER ALL BUT FAR WRN UPPER MI...PRECIP WILL NOT
FOLLOW IT E. THE 12Z/22 GFS CONTINUES TO MOVE THE MOISTURE /AND
THEREFOR THE PRECIP/ A LITTLE FARTHER E /OVERSPREADING MUCH OF WRN
UPPER MI/ WED NIGHT...BUT WILL GO WITH MOST OTHER MODELS IN KEEPING
IT FARTHER W...WHICH MAKES SENSE GIVEN DRY CONDITIONS AND RIDGING IN
PLACE TO THE E. WED NIGHT LOW LOOK QUITE WARM GIVEN 850MB TEMPS
STAYING AROUND 17C AND BREEZY S/SSE SFC WINDS. LOW OVER WRN UPPER
MI...WHERE IT WILL BE CLOUDIER...MAY NOT FALL BELOW 60...WITH LOWS
AOA 50 ELSEWHERE.
FOR THU...THE SHORTWAVE MOVES TO NEAR WRN UPPER MI LATE IN THE
DAY...BRINGING 992MB SFC LOW TO FAR WRN LAKE SUPERIOR/MN ARROWHEAD
BY 00Z FRI. PRECIP WILL REMAIN CONFINED TO FAR WRN UPPER MI/WRN LAKE
SUPERIOR THROUGH 00Z FRI...WITH STRONG SLY LOW LEVEL FLOW CONTINUING
TO BRING DRY AIR TO CENTRAL AND ERN UPPER MI. HIGH TEMPS THU LOOK TO
BE WARMEST OVER THE WRN HALF OF THE U.P. /EXCEPT NEAR IWD DUE TO
INCREASED CLOUD COVER/ IN THE MID TO UPPER 80S. OVER ERN UPPER
MI...HIGHS WILL RANGE FROM THE UPPER 60S NEAR LAKE MI TO AROUND 80
NEAR LAKE SUPERIOR. SFC WIND GUSTS AOA 30MPH LOOK COMMON ON
THU...WHICH WILL TURN ATTENTION TO FIRE WEATHER AS RH FALLS TO
AROUND 30 PERCENT OVER ALL BUT FAR WRN UPPER MI AND NEAR LAKE
SUPERIOR. MUCAPE AROUND 1000J/KG...0-1KM BULK SHEAR AROUND
40KTS...AND 0-6KM BULK SHEAR AOA 50KTS WILL BE SUPPORTIVE OF STRONG
TO SEVERE THUNDERSTORMS OVER WESTERN UPPER MICHIGAN LATE THU
AFTERNOON/EVENING...MAINLY ALONG AND JUST BEHIND THE COLD FRONT.
MAIN SEVERE WX THREATS WOULD BE LARGE HAIL/DAMAGING WINDS.
BY 06Z FRI...MODELS SHOW THE SHORTWAVE/SFC LOW NEAR NRN LAKE
SUPERIOR...WITH THE COLD FRONT OVER CENTRAL OR WRN UPPER MI. THIS
SHOULD BRING WIDESPREAD SHOWERS AND THUNDERSTORMS TO WRN UPPER
MI...BUT COVERAGE WILL DIMINISH AS PRECIP HEADS E INTO THE DRIER AIR
IN PLACE. COLD FRONT SHOULD BE EXITING ERN UPPER MI SHORTLY AFTER
12Z FRI...WITH THE GFS SHOWING QUICKER EASTWARD PROGRESS WITH THE
FRONT THAN MOST OTHER MODELS...SO WILL NOT USE AS FAST A SOLUTION AS
THE GFS.
500MB HIGH BUILDS INTO THE SRN MISSISSIPPI VALLEY BY 12Z SAT AS A
500MB LOW PUSHES INTO THE SW CONUS. A RIDGE FROM THE UPPER HIGH WILL
EXTEND OVER THE DAKOTAS AND MONTANA AT 12Z SAT...BUT WILL MOVE TO
THE WRN CWA BY 18Z SUN AS THE UPPER LOW MOVES TO MT. THIS BRINGS THE
COLD FRONT BACK N AS A WARM FRONT LATE SAT INTO SUN AS A 998MB SFC LOW
MOVES TO SD. PRECIP LOOKS TO MOVE S TO N ACROSS THE CWA SAT NIGHT
THROUGH SUN. MODELS BEGIN TO QUICKLY DIVERGE ON A SOLUTION PAST SUN
AS THE 00Z/22 ECMWF KEEPS THE UPPER LOW OVER MT/SRN SASK THROUGH MON
NIGHT...ANS THE GFS MOVES IT TO JAMES BAY BY 12Z TUE. WILL USE
CONSENSUS OF MODELS FOR SAT THROUGH NEXT TUE...WITH THE FORECAST
BECOMING INCREASINGLY UNCERTAIN SUN NIGHT THROUGH TUE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 725 AM EDT TUE MAY 22 2012
ALTHOUGH THERE WL BE AN INCRS IN MID CLD AT MAINLY IWD/CMX...EXPECT
VFR CONDITIONS TO PREVAIL WITH PLENTY OF LLVL DRY AIR. A TIGHTENING
PRES GRADIENT OVER FAR WRN UPR MI WL CAUSE S WINDS TO TURN GUSTY
WITH DAYTIME HEATING AT IWD TODAY. WITH NOCTURNAL COOLING/A MORE
STABLE THERMAL PROFILE TNGT...EXPECT LLWS AT THAT SITE UNDER THE
SHARPER PRES GRADIENT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EDT TUE MAY 22 2012
SRLY WINDS WILL INCREASE TONIGHT INTO WED AS HIGH PRES SHIFTS TO THE
EAST. EXPECT S WINDS UP TO 25-30 KTS WED INTO THURSDAY NIGHT UNDER
SHARPENING PRES GRADIENT BETWEEN THE DEPARTING HIGH AND A SLOWLY
APPROACHING LO PRES TROF FROM THE W. THE STRONGEST WINDS ARE
EXPECTED OVER CENTRAL LAKE SUP...WHERE TERRAIN INFLUENCE MAY ENHANCE
THE S WIND. THE WIND AT HIGHER PLATFORMS SUCH AS STANNARD ROCKS MAY
ALSO EXCEED 35 KTS...BUT THE HIGH STABILITY OVER THE RELATIVELY COOL
LAKE WATERS WILL PREVENT THESE STRONGER WINDS FROM MIXING TO THE
SURFACE. LOOK FOR LIGHTER WINDS UNDER 20 KTS ON FRI/SAT WITH A
RELATIVELY WEAK PRES GRADIENT ASSOCIATED WITH HIGH BUILDING INTO THE
REGION FOLLOWING A COLD FRONTAL PASSAGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS BILLINGS MT
924 PM MDT WED MAY 23 2012
.SHORT TERM...VALID FOR THU AND FRI...
DIURNALLY-DRIVEN SHOWER ACTIVITY IS WINDING DOWN AS OF 03 UTC WITH
THE ONSET OF COOLING IN THE BOUNDARY LAYER. LOW POPS REMAIN ACROSS
THE PLAINS UNTIL 06 UTC THOUGH BECAUSE RESIDUAL CONVECTIVE SHOWERS
COULD PERSIST FOR A WHILE AFTER SUNSET IN CYCLONIC FLOW ALOFT. THE
00 UTC HRRR SEEMS TOO AGGRESSIVE WITH ITS SHOWER COVERAGE AFTER 06
UTC THOUGH GIVEN RADAR TRENDS...SO WE STAYED THE COURSE WITH A DRY
FORECAST FOR MOST OF THE PLAINS OVERNIGHT. NOTE...HOWEVER...THAT A
MODEST AREA OF 500-300 HPA Q-VECTOR CONVERGENCE ACROSS SOUTHERN MT
AND NORTHERN WY AS SHOWN BY THE 00 UTC NAM AND 18 UTC GFS IS CAUSE
FOR LINGERING POPS ALL NIGHT IN THOSE AREAS. THAT FORCING COULD BE
PART OF THE REASON FOR THE PRECIPITATION AROUND SHERIDAN ALREADY.
OUR GOING FORECAST FOR TONIGHT HANDLES MOST OF THESE IDEAS WELL...
SO ONLY MINOR CHANGES WERE REQUIRED. THE FOCUS DURING THE NEXT FEW
DAYS WILL CERTAINLY BE ON THE POTENTIAL STORM...WHICH SHOULD BRING
SIGNIFICANT PRECIPITATION TO THE AREA. THE 18 UTC GFS AND NAM FROM
00 UTC STILL BOTH SUPPORT THIS NOTION...AND THE WINTER STORM WATCH
THAT STARTS THU EVENING FOR THE MOUNTAINS AND FOOTHILLS OVER SOUTH
CENTRAL MT LOOKS ON TRACK. SCHULTZ
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MADE A FEW CHANGES TO THE EXTENDED PERIOD TODAY...MAINLY WITH
REGARD TO TEMPS. MODELS REMAIN IN SOMEWHAT POOR AGREEMENT ON
SPECIFICS OF SYSTEM TRACKING THROUGH THE REGION AND WHAT FOLLOWS.
HAVE GENERALLY MAINTAINED INHERITED POPS...WITH NOD TOWARD WARM
AIR INTO THE EAST SATURDAY.
SATURDAY MORNING STILL LOOKS RELATIVELY ACTIVE AS UPPER LOW
PROCEEDS NORTH AND EASTWARD...BUT MODELS QUICKLY BEGIN TO
DIVERGE. THE GFS MOVES THE LOW MUCH MORE QUICKLY EASTWARD INTO
NORTHWESTERN ND BY SUNDAY NIGHT...MEANWHILE THE EC TAKES MORE
NORTHERLY TACK TO START...MOVING INTO NORTH CENTRAL MONTANA IN
THE SAME TIME FRAME. THE LOW DOES NOT REACH NORTHWESTERN ND UNTIL
MONDAY AFTERNOON. DUE TO MORE WESTERLY LOCATION OF THE LOW...IT
ALSO APPEARS THAT SOME WARMER AIR WILL BE DRAWN UP INTO EASTERN
ZONES. EXACT EXTENT OF WARM AIR INTRUSION IS STILL
UNCERTAIN...BUT HAVE RAISED HIGHS SLIGHTLY IN THE EAST. THIS AIR
ALSO LOOKS A BIT DRIER...SO HAVE TAPERED POPS OFF A BIT IN THE
EAST FOR SATURDAY. THE UPPER LOW TRANSITIONS OUT OF THE REGION
THROUGH SUNDAY...TIMING AND TRACK ARE AGAIN ISSUES. AS LOW LIFTS
OUT OF THE REGION WE SHOULD GET ANOTHER SHOT OF COLD AIR...AND
SOME WRAP AROUND PRECIP...SO HAVE KEPT GOING POPS IN PLACE.
EITHER WAY...THE LOCATION AND MOVEMENT...OR LACK THEREOF...OF THE
UPPER LEVEL HIGH PRESSURE RIDGE OVER THE SOUTHEASTERN CONUS WILL
DECIDE MOTION AND TIMING OF THE UPPER LEVEL LOW.
MODELS HAVE COME BACK INTO SOME DEGREE OF AGREEMENT MONDAY...AS
RIDGING REDEVELOPS... WITH DRY NORTHWEST FLOW OVER THE FORECAST
AREA. HAVE KEPT SLIGHT POPS IN PLACE AT THIS TIME...BASED ON
POTENTIAL AIRMASS TYPE SHOWERS...BUT SHOULD GENERALLY SEE DRYING
CONDITIONS AND START TO WARMING TREND. NEXT SHORTWAVE TROF SWINGS
ACROSS THE AREA TUESDAY...BRINGING SOME POTENTIAL FOR MORE SHOWER
ACTIVITY. DUE TO TIMING OF THE WAVE...THIS WILL LIMIT WARMUP IN
WESTERN ZONES...FROM KBIL WEST...BUT EASTERN AREAS SHOULD STILL
SEE TEMPS APPROACHING 70. RIDGING QUICKLY BEGINS BUILDING BACK
INTO THE REGION OVERNIGHT TUESDAY...RESULTING IN MUCH WARMER
TEMPS. HAVE RAISED HIGHS SIGNIFICANTLY FOR WEDNESDAY. AAG
&&
.AVIATION...
WIDELY SCATTERED SHOWERS WILL OCCUR OVER THE REGION THROUGH 06Z...
WITH SCATTERED SHOWERS OVER THE KSHR AREA. LOCALIZED MVFR
CONDITIONS WILL BE POSSIBLE IN ANY HEAVIER SHOWERS. VFR
CONDITIONS WILL PREVAIL AFTER 06Z. HOWEVER...SCATTERED SHOWERS
WILL CONTINUE AROUND KSHR WITH POSSIBLE MVFR CONDITIONS. EXPECT
AREAS OF MOUNTAIN OBSCURATION THROUGH THE NIGHT. CHANCES FOR
SHOWERS WILL INCREASE OVER THE AREA ON THU. A FEW AFTERNOON
THUNDERSTORMS WILL BE POSSIBLE AS WELL. LOCALIZED MVFR CONDITIONS
WILL BE POSSIBLE WITH THE PRECIPITATION. MOUNTAIN OBSCURATION WILL
INCREASE THROUGH THE DAY. ARTHUR
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 042/058 038/049 039/050 037/052 037/063 044/062 044/069
24/T 36/W 87/R 65/W 22/T 22/W 32/W
LVM 034/053 032/042 032/046 030/050 033/059 036/059 036/071
34/T 68/W 87/R 75/W 23/T 33/W 32/W
HDN 041/060 037/054 044/061 037/054 037/065 044/063 044/072
24/T 36/W 75/R 64/W 32/T 22/W 32/W
MLS 044/061 037/057 044/062 040/056 040/062 043/064 044/070
24/T 24/W 75/R 65/W 22/T 23/W 32/W
4BQ 042/060 037/057 046/067 039/061 040/064 043/068 044/069
23/T 24/W 65/R 53/W 22/T 22/W 32/W
BHK 040/062 034/057 045/057 040/061 039/061 041/065 045/065
24/T 23/W 75/R 54/W 22/T 23/W 33/W
SHR 038/056 035/049 039/064 036/058 035/062 039/067 040/069
43/T 36/T 65/R 64/W 22/T 22/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER STORM WATCH IN EFFECT FROM THURSDAY EVENING THROUGH
LATE SATURDAY NIGHT FOR ZONES 56-66>68.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
338 AM MDT TUE MAY 22 2012
.SHORT TERM...VALID FOR TDY AND WED...
120KT H3 JET CURRENTLY NOSING THROUGH OR INTO SOUTHERN ID...WITH A
LARGE AREA OF SHOWERS AFFECTING WESTERN INTO NORTH CENTRAL MONTANA
TONIGHT. PV MAX APPROACHING WEST YELLOWSTONE IS ENHANCING THE
SHOWERS IN OUR WEST EARLY THIS MORNING...AND PER THIS TREND AND
LATEST RUC EXPECT A GOOD CHANCE OF SHOWERS ACROSS OUR WEST AND
NORTHWEST PARTS THROUGH AROUND 13Z. SCATTERED SHOWERS SHOULD PUSH
THRU THE BILLINGS AREA BETWEEN 10-13Z. HAVE MADE SOME ADJUSTMENTS
TO THE 6-12Z POP GRID TO COVER THIS ACTIVITY...WHICH IS PUSHING A
BIT MORE AGGRESSIVELY TO THE EAST SOONER THAN PREVIOUSLY THOUGHT.
NEXT SHORTWAVE EMBEDDED IN THE QUICKENING PACIFIC FLOW IS STILL
OFF THE COAST...AND WILL MOVE INLAND AND AFFECT OUR AREA LATER
TODAY AND TONIGHT. FRONTOGENESIS WILL INCREASE BEHIND THE CURRENT
ENERGY AND AHEAD OF THIS NEXT WAVE...IN AN AREA OF GOOD MOISTURE
TRANSPORT. FURTHERMORE...THERE IS AN AREA OF WEAK PRESSURE FALLS
IN IDAHO ASSOCIATED WITH THE JET STREAK...AND THIS MAY REDUCE/LAG
THE DOWNSLOPING WINDS EXPECTED WITH THE COLD ADVECTION SET TO
OCCUR TODAY. SO...EXPECT MORE SHOWERS TO DEVELOP TO OUR WEST THIS
MORNING AND SPREAD INTO OUR AREA FROM LATE MORNING INTO THE
EVENING...WITH A GRADUAL SAGGING TO THE SOUTH AS STRONGER
FRONTOGENESIS AND JET DIVERGENCE DOES THE SAME. HAVE RAISED POPS
A BIT MORE OVER OUR MOUNTAINS PER THE FAVORABLE OROGRAPHIC
FLOW...MOISTURE AND INSTABILITY. 700MB TEMPS WILL FALL TO NEAR -4C
TONIGHT...THUS EXPECT SOME SNOW ACCUMULATION OVER THE WEST SLOPES.
CYCLONIC FLOW WITH UPPER LEVEL TROFFING AND RELATIVELY COLD TEMPS
ALOFT...AND ADDITIONAL SHORTWAVE ENERGY EMBEDDED IN THE PACIFIC
FLOW...WILL KEEP SHOWERY WEATHER GOING THROUGH WEDNESDAY AND
WEDNESDAY NIGHT. LOW LEVEL DOWNSLOPE WINDS WILL LIMIT OUR PCPN
COVERAGE TO SCATTERED ACROSS THE LOWER ELEVATIONS...GREATEST WITH
DAYTIME HEATING ON WEDNESDAY...BUT OUR WEST SLOPES WILL CONTINUE
TO FAVORED WITH A MIX OF RAIN AND SNOW SHOWERS. HAVE RAISED POPS
OVER OUR WESTERN HIGH TERRAIN AND GIVEN ELEVATIONS ABOVE 7KFT A
LITTLE SNOW ACCUMULATION EACH PERIOD. AT THE VERY LEAST...THE
ONSET OF THIS MUCH COOLER PATTERN WILL STOP WHAT HAS BEEN AN EARLY
HIGH ELEVATION SNOW MELT FOR A FEW DAYS.
AS FOR TEMPERATURES...HIGHS TRICKY TODAY WITH MIXING/WARMING EARLY
ON BECOMING OFFSET BY COLD ADVECTION WHICH WILL INCREASE BY LATE
MORNING AND INTO THE AFTERNOON. EXPECT TEMPS TO DROP INTO THE 50S
WITH THE SHOWER ACTIVITY. COOL POST FRONTAL AIRMASS WILL BE IN
PLACE FOR WEDNESDAY. WITH WEST WINDS AND GOOD MIXING WE SHOULD
STILL GET INTO THE UPPER 50S TO MID 60S ACROSS THE PLAINS...THE
BEGINNING OF AN EXTENDED PERIOD OF BELOW NORMAL TEMPERATURE DAYS.
JKL
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
EXTENDED FORECAST THROUGH THE HOLIDAY WEEKEND CONTINUES TO LOOK
UNSEASONABLY COOL AND WET. MODEL AGREEMENT HAS TAKEN A HIT WITH
THE LATEST RUNS AS THE GFS HAS TRENDED LESS AMPLIFIED DESPITE THE
PRESENCE OF A VERY STRONG DOWNSTREAM RIDGE COMPARED TO OTHER
MODELS WHICH REMAIN SIMILAR TO LAST NIGHTS AND MONDAY MORNINGS
RUNS.
THURSDAY...COLDER LOW LEVEL AIR BUILDS IN FROM CANADA WITH SOME
SEMBLANCE OF UPSLOPE FLOW AND FRONTOGENESIS HELPING TO GENERATE
SHOWERS ACROSS THE AREA. TEMPERATURES LOOK QUITE COOL WITH
FORECAST HIGHS IN THE 50S...THOUGH THIS MAY BE TOO WARM GIVEN
COLD ADVECTION AND PLENTY OF CLOUDS/PRECIPITATION. FLOW ALOFT
BEGINS TO BACK TO THE SOUTHWEST LATE IN THE DAY WHICH WILL
ENHANCE MID LEVEL OVER RUNNING KEEPING PRECIPITATION GOING INTO
THE NIGHT WITH THE HEAVIEST ACCUMULATIONS LIKELY OVER SOUTHERN
ZONES.
FRIDAY THROUGH SUNDAY...TRACK AND TIMING OF UPPER LOW CONTINUE TO
BE PROBLEMATIC WITH OPERATIONAL MODELS AND ENSEMBLE MEAN
SOLUTIONS CHANGING RUN TO RUN. THE ECMWF LOOKS LIKE THE MOST
STABLE SOLUTION AT THIS POINT AND ITS AMPLIFIED SOLUTION IS
SUPPORTED BY STRONG RIDGING DOWNSTREAM OVER THE EASTERN US. 06Z
NAM HAS TRENDED TOWARD THE 00Z ECMWF THIS MORNING AS WELL WITH
ADDITIONAL SUPPORT FROM THE CANADIAN SOLUTIONS. THE GFS WENT MUCH
LESS AMPLIFIED WITH THE UPPER LOW AND BLEEDS ENERGY OUT OF THE
SYSTEM ACROSS WYOMING KEEPING HEAVIEST PRECIPITATION TO THE SOUTH
OF THE AREA...THOUGH STILL SUPPORTING HIGH POPS JUST LESS QPF FOR
FRIDAY AND SATURDAY. GENERALLY PREFER A MORE AMPLIFIED SOLUTION
AS LONG AS THE DOWNSTREAM RIDGING REMAINS IN PLACE THUS
DISCOUNTING THE GFS AT THIS TIME AND LEANING TOWARD AN
ECMWF/ENSEMBLE MEAN SOLUTION. THIS SOLUTION PRODUCES A DEEP
SOUTHERLY DIFFLUENT FLOW OVER THE AREA FRIDAY INTO SATURDAY AS
THE UPPER LOW MOVES FROM CENTRAL CALIFORNIA INTO CENTRAL MONTANA.
A SURFACE LOW DEVELOPS OVER NORTHEAST WYOMING ALLOWING STRONG
ISENTROPIC LIFT IN THE LOWER LEVELS TO DEVELOP OVER MOST OF THE
AREA SUPPORTING 1 TO 2 INCH TYPE PRECIPITATION AMOUNTS ACROSS THE
AREA. EASTERLY SURFACE GRADIENT WILL ALSO SUPPORT UPSLOPE INTO
AREA MOUNTAINS AND FOOTHILLS WHICH COMBINED WITH DIVERGENCE ALOFT
WILL ENHANCE PRECIPITATION NEAR THE MOUNTAINS. AS A RESULT HAVE
LIKELY OR BETTER POPS IN THE MOUNTAINS WITH HIGH CHANCE TO LIKELY
POPS FOR THE LOWER ELEVATIONS. CURRENTLY HAVE TEMPERATURES
FORECAST IN THE 50S ACROSS MOST OF THE AREA FRIDAY AND
SATURDAY...BUT TEND TO THINK THIS WILL BE TOO WARM SHOULD THE
ECMWF SOLUTION VERIFY ESPECIALLY SATURDAY. WITH UPPER LOW AND
PLENTY OF PRECIPITATION ON SATURDAY HIGHS COULD STAY IN THE LOW
TO MID 40S...WITH 30S IN THE FOOTHILLS.
SNOW...FREEZING LEVELS WILL BE QUITE LOW FRIDAY MORNING
SUPPORTING A MIX OF RAIN AND SNOW FOR WESTERN FOOTHILLS
LOCATIONS. AS THE UPPER LOW MOVES INTO THE AREA FRIDAY NIGHT
EXPECT ADDITIONAL LOWERING OF FREEZING LEVELS WITH THE POTENTIAL
FOR HEAVY SNOW OVER AREA MOUNTAINS AS 700MB TEMPERATURES DROP TO
AROUND -10C. THIS WOULD BRING THE CHANCE FOR ACCUMULATING SNOW IN
THE RED LODGE...NYE AND POSSIBLY LIVINGSTON AREAS FRIDAY
NIGHT/SATURDAY MORNING...ALONG WITH HEAVY SNOW ALONG THE
BEARTOOTH PASS. WENT AHEAD AND BUMPED QPF AND SNOW ACCUMULATIONS
UP FOR THESE PERIODS BUT AMOUNTS ARE DEPENDENT ON A FAVORABLE
TRACK TO THE UPPER LOW AND COULD BE OVERDONE IF THE LOW TRACK IS
FURTHER WEST OR SOUTH. ANYONE PLANNING TRAVEL TO THE HIGH
COUNTRY...INCLUDING ALONG THE BEARTOOTH HIGHWAY...SHOULD REMAIN
ALERT TO THE LATEST FORECASTS AND SHOULD PROBABLY PLAN ON WINTER
DRIVING CONDITIONS.
SUNDAY...MOST OF THE MODELS INDICATING DOWNSLOPE WINDS WILL SCOUR
OUT PRECIPITATION SUNDAY AFTERNOON...THUS HAVE TRENDED POPS DOWN
SUNDAY INTO MONDAY. HOWEVER THERE IS A CHANCE THAT A MORE
AMPLIFIED SYSTEM WILL MOVE SLOWER LINGERING PRECIPITATION INTO
MONDAY...SO HAVE NOT GONE DRY. NORTHWEST WINDS WILL BECOME GUSTY
SUNDAY AFTERNOON INTO SUNDAY NIGHT WHICH WILL HELP HOLD
TEMPERATURES WARMER THAN SATURDAY NIGHT.
MONDAY THROUGH WEDNESDAY...ECMWF INDICATING ZONAL FLOW WHILE GFS
DRIVES ANOTHER PACIFIC SYSTEM INTO THE AREA. KEEPING SOME LOW
POPS IN THE FORECAST ALONG WITH WARMER TEMPERATURES FOR NOW.
CHAMBERS
&&
.AVIATION...
UPPER LEVEL STORM SYSTEM IS MOVING INTO WESTERN AREAS THIS
MORNING WITH SCATTERED RAIN SHOWERS. LOCAL MVFR CONDITIONS ARE
EXPECTED FROM KBIL WEST TO KLVM THROUGH 18Z. THIS AFTERNOON MVFR
OR LOWER CONDITIONS WILL BECOME PREDOMINANT WEST OF A ROUNDUP TO
SHERIDAN WYOMING LINE...WITH SCATTERED SHOWERS AND THUNDERSTORMS
TO THE EAST RESULTING IN LOCAL MVFR CONDITIONS FOR KMLS.
OCCASIONAL MOUNTAIN OBSCURATION THIS MORNING WILL BECOME
PREDOMINANT THIS AFTERNOON AND CONTINUE THROUGH TONIGHT.
CHAMBERS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 071 045/062 042/055 040/053 040/054 040/065 044/068
7/T 44/T 36/T 55/T 66/T 53/T 22/T
LVM 062 037/055 034/052 033/049 034/052 032/061 038/066
7/T 45/T 36/T 56/T 66/T 73/T 22/T
HDN 075 044/064 042/056 040/056 041/059 041/067 044/069
7/T 54/T 46/T 55/T 66/T 52/T 22/T
MLS 077 047/067 044/057 042/056 043/059 043/066 045/069
6/T 42/W 34/T 34/T 55/T 53/T 22/T
4BQ 080 047/064 043/056 040/055 044/062 042/067 044/071
5/T 63/T 34/T 44/T 75/T 53/T 22/T
BHK 081 045/064 041/060 040/053 044/057 043/064 044/069
5/T 42/W 24/T 34/T 55/T 53/T 22/T
SHR 077 042/060 039/054 037/053 039/060 039/063 040/067
4/T 64/T 45/T 45/T 66/T 53/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
1027 PM MDT MON MAY 21 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
10 PM UPDATE...AREAS OF SHOWERS CONTINUE TO MOVE INTO THE WESTERN
AREAS AND WEAKEN AS THEY PUSH EAST. KEPT HIGH POPS FOR THE WEST
AND SLIGHT OR ISOLATED POPS IN THE EAST. DROPPED THUNDER FOR THE
NIGHTTIME HOURS. MODELS SHOW THAT THUNDER DEVELOPING MID DAY OVER
THE FORECAST AREA AND SPREADING EAST DURING THE EARLY
AFTERNOON...AND BECOMING SEVERE IN NORTH DAKOTA. ANY SLOWING UP OF
THE FRONT COULD BRING A SHOT OF SEVERE THUNDER TO PLENTYWOOD-
SIDNEY-WIBAUX AREAS IN THE AFTERNOON. BUFR NAM SOUNDINGS HAVE THE
INVERTED V... PW/S NEARING 1.00... AND A GOOD TURN IN THE WIND
FIELD FROM SFC TO 850 MB. WILL NOT UPDATE DAY TWO OF THE
FORECAST...BUT COULD BE BRIEFLY A CONCERN IN THE EARLY AFTERNOON
FOR THE FAR EASTERN ZONES. PROTON
8 PM UPDATE...AN ARC OF SHOWERS WITH A FLASH OR TWO OF THUNDER
CONTINUE TO PUSH EAST ACROSS THE CMR AND GARFIELD COUNTY THIS
EVENING. THE ARC OF SHOWERS/STORMS HAS PRODUCED 30 TO 50 MPH WIND
GUSTS AS IT PASSES OVER OBSERVATION SITES. THE LATEST HRRR MODEL
PUSHES THIS ARC THROUGH AND DIMINISHES IT THROUGH 10 PM. WILL HAVE
TO WATCH THE AREA OF SHOWERS TO THE EAST OF GREAT FALLS... THE
HRRR BRINGS THAT THROUGH THE WESTERN CMR AND UP FORT PECK LAKE
THROUGH MIDNIGHT. MAY HAVE TO UPDATE AT 10 PM TO BETTER DEFINE
OVERNIGHT POPS AND QPF. PROTON
6 PM UPDATE...AN AREA OF THUNDERSTORMS HELD TOGETHER OVER CENTRAL
MONTANA AND IS MOVING INTO THE WESTERN ZONES. UPDATED THE FORECAST
TO ADD GUSTY WINDS SINCE UPSTREAM OBSERVATIONS HAVE SOME GUSTS TO
30 MPH. INCREASED POP COVERAGE FOR THE CMR AND THE WEST SIDE OF
FORT PECK LAKE WITH THE HRRR MODEL HITTING THIS AREA HARDER WITH
RAINFALL THIS EVENING. PROTON
UPPER TROF OFF THE PACIFIC NORTHWEST EXPECTED TO TRANSITION INTO
MONTANA DURING THE SHORT TERM. SOUTHWEST FLOW ALOFT ALREADY
PUSHING INCREASED MOISTURE INTO THE WESTERN PART OF THE STATE AND
A FEW HIGH BASED THUNDERSTORMS ARE MOVING ACROSS CENTRAL MONTANA
THIS AFTERNOON. AIRMASS OVER EASTERN MONTANA STILL QUITE DRY AND
AFFECTED BY PROXIMITY OF RIDGE AXIS BUT JET STREAK PUSHING ACROSS
CENTRAL MONTANA INTO SOUTHERN SASKATCHEWAN OVERNIGHT WILL HELP
SPREAD THUNDERSTORMS OVER THE NORTHWEST ZONES. JET ALSO PUSHES
COLD FRONT ACROSS THE STATE OVERNIGHT AND WITH COLD AIR ADVECTION
...TIGHTENING PRESSURE GRADIENT AND DOWNSLOPE FLOW WITH JET EXPECT
WINDS TO INCREASE ACROSS THE REGION ON TUESDAY. SHOULD BE STRONG
ENOUGH FOR LAKE WIND ADVISORY BY MIDDAY...EXTENDING INTO THE
EVENING HOURS IF NOT THROUGH THE NIGHT.
STRONG WESTERLIES AND CAA BEHIND THE FRONT WILL RESULT IN SOME
INHIBITION OF SHOWERS FOR TUESDAY MORNING. ANOTHER JET STREAK
PUSHES ACROSS NORTHERN WYOMING IN THE AFTERNOON...WHICH COULD HELP
DEVELOP CONVECTION OFF THE HIGHER TERRAIN IN SOUTHWEST MONTANA AND
PUSH IT INTO THE PLAINS.
BY WEDNESDAY THE BETTER LIFT MOVES EAST AS THE UPPER TROF SLIDES
INTO MONTANA. COLD AIR ALOFT COULD RESULT IN ENOUGH INSTABILITY
FOR A FEW SHOWERS BUT OVERALL TREND WILL BE DRY AND COOL. LOW
LEVELS MIX ENOUGH THAT ANOTHER LAKE WIND ADVISORY MAY BE NEEDED.
EBERT
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
MADE SOME ADJUSTMENTS TO THE LONG TERM FORECAST PERIOD. A BROAD
UPPER LEVEL TROUGH WILL DOMINATE THE WEATHER PATTERN OVER THE
ROCKIES...INTER-MOUNTAIN WEST...AND NORTHERN HIGH PLAINS THROUGH
MOST OF THE EXTENDED PERIOD. LOOKS LIKE IT UNFOLD IN TWO PHASES.
FIRST...THE LONG AND BROAD UN-AMPLIFIED TROUGH WILL DROP THROUGH
THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS FROM WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT.
FROM THURSDAY NIGHT ONWARD...AN UPSTREAM UPPER LEVEL LOW CENTER
LOBE BECOMES THE STAR OF THE SHOW AS IT QUICKLY DEEPENS AND DIGS
DOWN OVER THE CASCADE MOUNTAIN RANGE...BOTTOMING OUT OVER LAS
VEGAS...THEN QUICKLY CHANGING COURSE AND HEADING NORTHEAST THROUGH
SUNDAY...EVENTUALLY MOVING DIRECTLY OVER OUR CWA.
MODELS ARE IN MODERATELY GOOD AGREEMENT WITH THIS GENERAL WEATHER
PATTERN...BUT ANY MORE DETAILS GET KIND OF MUDDLED. ESPECIALLY
WITH THE NORTHWARD PROGRESSION OF THIS LATE UPPER LOW THROUGH THE
WEEKEND. THE GFS DIFFUSES AND OPENS UP THIS LOW CENTER QUITE
QUICKLY...BUT THE EC HOLDS ONTO IT AND EVEN DEEPENS IT OVER OUR
CWA WHICH WOULD RESULT IN MUCH COLDER TEMPERATURES THAN WE HAVE
CURRENTLY FORECASTED.
TRIED TO SHOW AN EXTENDED MODEL BLEND...BUT DID NOT GIVE EQUAL
WEIGHT TO THE EXTREME EC OUTLIER AND WOULD ADVISE DOING SO UNTIL
EXTENDED MODELS SHOW BETTER AGREEMENT.
OVERALL...EXPECT ALTERNATING PERIODS OF RAIN SHOWERS AND DRY SLOTS
WITH GENERALLY COOLER TEMPERATURES AS THIS LARGE UPPER TROUGH
SYSTEM SPREADS ACROSS MOST OF THIS PORTION OF THE CONTINENT.
BMICKELSON
PREVIOUS LONG TERM DISCUSSION...MODELS TAKE ONE UPPER TROUGH TO
THE EAST THURSDAY AND THURSDAY NIGHT WHILE DIGGING ANOTHER OVER
THE PACIFIC NORTHWEST. WHILE THE BULK OF THE MOISTURE WITH
THURSDAY`S TROUGH IS EXPECTED TO BE TO THE EAST...THERE WILL BE
ENOUGH LINGERING MOISTURE AND INSTABILITY TO WARRANT A CHANCE OF
SHOWERS.
ON FRIDAY...THE FORECAST WILL BE BETWEEN SYSTEMS IN A SOUTHWEST
FLOW ALOFT AS A CLOSED LOW DEVELOPS IN CALIFORNIA IN THE WEST
COAST UPPER TROUGH. MODELS DIFFER BETWEEN A DRY SW FLOW (GFS) AND
MOIST SW FLOW (ECMWF) ALOFT. WILL MAINTAIN EITHER A CHANCE OR
SLIGHT CHANCE OF SHOWERS.
MODELS GRADUALLY LIFT THIS LOW NORTH OVER THE WEEKEND AND BRING IT
ACROSS MONTANA ON SUNDAY. IF THIS FORECAST HOLDS TRUE...IT COULD
BE A VERY WET WEEKEND ACROSS THE REGION. WILL MAINTAIN A CHANCE
OF SHOWERS FOR NOW UNTIL BETTER RUN TO RUN AGREEMENT IS
MAINTAINED.
THE LOW LIFTS NORTH NEXT MONDAY DIMINISHING THE CHANCE OF SHOWERS. FORRESTER
&&
.AVIATION...
AN APPROACHING PACIFIC LOW PRESSURE SYSTEM WILL BRING INCREASED
CLOUDINESS AND RAIN SHOWERS TO NORTHEAST MONTANA TOWARD THE END OF
THIS TAF PERIOD. VFR CONDITIONS ARE EXPECTED TO PREVAIL WITH ONE
BRIEF EXCEPTION...KGGW MAY SEE MVFR CONDITIONS WITH A BRIEF RAIN
SHOWER TONIGHT AND AGAIN BY MID DAY TUESDAY. A COLD FRONT WILL
PUSH RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS THROUGH THE
ENTIRE REGION. WINDS WILL SHIFT AROUND TO COME FROM THE NORTHWEST AND
WEST DURING THE LATE MORNING HOURS ON TUESDAY...THEN INCREASE INTO
THE 25G35KT RANGE BY MID DAY. OVERALL...EXPECT INCREASED CROSSWIND
CONCERNS FOR NORTH TO SOUTH ORIENTED RUNWAYS DURING THE MID DAY
AND AFTERNOON HOURS ON TUESDAY WITH BRIEF MODERATE RAIN SHOWERS.
BMICKELSON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 10 AM TO 9 PM MDT TUESDAY FOR FORT PECK
LAKE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1104 PM CDT WED MAY 23 2012
.UPDATE...KUEX INDICATES CONVECTION SPREADING IN AERIAL COVERAGE
ACROSS THE NORTHWESTERN ONE-THIRD OF THE CWA. SHORT TERM GUIDANCE
CONTINUES TO SUGGEST THIS A TREND WHICH WILL CONTINUE. DEEP LAYER
MUCAPE VALUES NEAR 1000J/KG AND DEEP LAYER BULK SHEAR NEAR 50KTS
WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL. A NEW SEVERE
THUNDERSTORM WATCH HAS BEEN ISSUED WHICH COVERS THE ENTIRE CWA
THROUGH 10Z. FORECAST HAS BEEN UPDATED TO INCLUDE THIS NEW SEVERE
THUNDERSTORM WATCH.
&&
.PREV DISCUSSION... /ISSUED 949 PM CDT WED MAY 23 2012/
UPDATE...EVENING UPPER AIR ANALYSIS INDICATES TROUGHING OVER THE
WESTERN CONUS WITH A RIDGE OVER THE EAST. MID AND UPPER LEVEL JET
ENERGY EXTENDS FROM THE WEST-CENTRAL CONUS...SOUTHEAST INTO THE
MID ROCKY MOUNTAIN RANGE AND THEN NORTHEAST ACROSS THE CENTRAL
PLAINS. A ~100KT UPPER LEVEL JET STREAK AND A ~70KT MID LEVEL JET
STREAK IS NOTED ACROSS THE WEST-CENTRAL CONUS AND BEGINNING TO
PUSH INTO THE CENTRAL PLAINS. WATER VAPOR IMAGERY SHOWS A MID
LEVEL SHORT WAVE APPROACHING THE MID ROCKY MOUNTAIN RANGE. AT THE
SURFACE A COLD FRONT EXTENDS FROM NEAR KOMA...TO NEAR KCNK...TO
NEAR KDDC. LOW LEVEL FLOW IS FROM THE THE NORTHEAST ACROSS MUCH OF
OUR CWA AS A RESULT...ALTHOUGH LOCATIONS FROM THAYER COUNTY TO
MITCHELL COUNTY...STILL AHEAD OF THE LOW LEVEL BAROCLINIC
ZONE...REMAIN FROM THE SOUTHEAST. KUEX SHOWS A THIN LINE OF
CONVECTION...ALONG THE LOW LEVEL BAROCLINIC ZONE...EXTENDING FROM
THAYER COUNTY TO MITCHELL COUNTY...BUT ADDITIONAL CONVECTION IS
NOT FIRING FARTHER NORTHWEST ACROSS MUCH OF THE REST OF THE CWA.
SHORT TERM GUIDANCE SUGGESTS SURFACE-BASED CONVECTION WILL REMAIN
POSSIBLE ALONG THE LOW LEVEL BAROCLINIC ZONE THROUGH 04Z OR
SO...HOWEVER THIS ACTIVITY SHOULD DIMINISH THEREAFTER AS DIABATIC
HEATING IS COMPLETELY LOST AND REMNANT FORCING ALONG THE
BAROCLINIC ZONE REMAINS FAIRLY WEAK. THE INDIRECT THERMAL
CIRCULATION WITHIN THE LEFT-FRONT QUAD OF THE APPROACHING MID
LEVEL JET STREAK...ALONG WITH CONTINUALLY INCREASING OMEGA AHEAD
OF THE MID LEVEL SHORT WAVE...WILL CONTINUE TO PROMOTE
PRECIPITATION ACROSS MUCH OF THE CWA THROUGH THE OVERNIGHT HOURS.
AT THIS TIME IT APPEARS THE BULK OF THE FORCING OVERNIGHT WILL BE
RELEGATED TO THE NORTHERN HALF OF THE CWA WHICH IS WHERE MOST OF
THE PRECIPITATION WILL BE REALIZED. SPC MESO-ANALYSIS INDICATES
DEEP LAYER MUCAPE VALUES OF AROUND 1000J/KG CURRENTLY IN EXISTENCE
ACROSS MUCH OF THE CWA...WITH DEEP LAYER SHEAR OF AROUND 60KTS.
THE COMBINATION OF MODERATE INSTABILITY AND VERY STRONG DEEP LAYER
SHEAR WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL ACROSS MUCH
OF THE CWA THROUGH EARLY MORNING THURSDAY.
WENT AHEAD AND UPDATED THE FORECAST WITH SLIGHT CHANGES MADE TO
HOURLY GIRDS TO BETTER REFLECT CURRENT TRENDS...ESPECIALLY
REGARDING CLOUD COVER. CURRENT POPS ACROSS NORTHERN PORTIONS OF THE
CWA LOOK RIGHT ON FOR TONIGHT AND THUS RAIN CHANCES WERE LEFT AS IS.
PREV DISCUSSION... /ISSUED 637 PM CDT WED MAY 23 2012/
AVIATION...00Z KGRI TAF. THUNDERSTORM DEVELOPMENT COULD OCCUR
ALONG A SURFACE COLD FRONT CONTINUING TO MOVE TO THE SOUTHEAST.
THIS SURFACE CONVECTION SHOULD REMAIN SOUTHEAST OF THE TERMINAL.
LATER ON TOWARD LATE EVENING...A LOW-LEVEL JET WILL ENCOURAGE
SEVERE THUNDERSTORMS TO DEVELOP AND LINGER INTO THE EARLY
OVERNIGHT HOURS. WIND MAY BE A BIT GUSTY FOR THURSDAY...WITH SOME
SMALL CHANCES OF THUNDERSTORMS. HOWEVER...CHANCES OF PRECIPITATION
ON THURSDAY ARE SMALL ENOUGH TO LEAVE OUT OF THE FORECAST FOR NOW.
PREV DISCUSSION... /ISSUED 419 PM CDT WED MAY 23 2012/
UPDATE...SENT AN UPDATE TO THE FORECAST TO INCLUDE SEVERE
THUNDERSTORM WATCH 293 FOR PORTIONS OF THE FORECAST AREA THROUGH
11 PM CDT. THE GREATEST POTENTIAL FOR ANY SEVERE STORMS WILL
REMAIN WITH AND ALONG EITHER SIDE OF A SLOWLY PROGRESSING COLD
FRONT...WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY
CONCERNS WITH ANY STORMS THAT DO DEVELOP.
PREV DISCUSSION... /ISSUED 400 PM CDT WED MAY 23 2012/
SHORT TERM...A FAIRLY ACTIVE START TO THE FORECAST IS EXPECTED
THIS EVENING AS A COLD FRONT SLOWLY MAKES ITS WAY ACROSS SOUTH
CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...WITH AN ASSOCIATED MID
LEVEL LOW PRESSURE SYSTEM TO THE WEST EXPECTED TO HELP BRING SOME
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE
FORECAST AREA DURING THE OVERNIGHT HOURS TONIGHT.
SHORT TERM MODELS ARE IN MODERATE DISAGREEMENT WITH INITIATION OF
CONVECTION ALONG A PASSING COLD FRONT...CURRENTLY DRAPED FROM NEAR
NORFOLK...ACROSS GRAND ISLAND...SOUTH WESTWARD TOWARDS HOLDREGE.
THIS FRONT HAS BEEN VERY SLOW TO WORK ITS WAY ACROSS THE FORECAST
AREA THIS AFTERNOON...AND SO FAR HAS YET TO PRODUCE ENOUGH FORCING
TO BREAK LOW LEVEL CAP. 12Z NAM AND WRF BOTH DID TRY AND INITIATE
CONVECTION...BUT 18Z NAM AND LATEST HRRR BOTH HOLD OFF ANY
WIDESPREAD SHOWER OR THUNDERSTORM ACTIVITY TILL FORCING FROM MID
LEVEL LOW TO OUR WEST APPROACHES CENTRAL NEBRASKA AROUND MIDNIGHT.
THAT BEING SAID...INGREDIENTS ARE IN PLACE...AS LATEST MESO
ANALYSIS SHOWS A FINGER OF 2000+ J/KG OF CAPE ACROSS THE LOCAL
AREA NEAR THE SLOWLY PROGRESSING FRONT...AND LITTLE INHIBITION AS
WELL AS DEVELOPING CU FIELD IN SATELLITE. PER CONSENSUS AMONG
MODELS...DID BACK OFF ON INITIATION OF CONVECTION THIS
AFTERNOON...BUT INSERTED MENTION OF SEVERE STORMS AFTER 00Z...AS
COMBINATION OF SHEAR AND INSTABILITY SHOULD BE SUFFICIENT FOR SOME
SUPERCELLS TO DEVELOP IF INITIATION CAN BE REALIZED NEAR THE
FRONT.
BEHIND THE FRONT...AS THE MID LEVEL SHORTWAVE APPROACHES THE
REGION...BROADER SCALE FORCING SHOULD BE AMPLE ENOUGH TO DEVELOP
WIDESPREAD CONVECTION ACROSS THE LOCAL AREA BY AROUND
MIDNIGHT...CONTINUING INTO THE OVERNIGHT HOURS...SO THE POTENTIAL
FOR SEVERE HAIL AND STRONG WINDS REMAIN A CONCERN.
THEREAFTER...THE ATMOSPHERE SHOULD BEGIN TO STABILIZE BEHIND THE
DEPARTING MID LEVEL WAVE...WITH A SMALL CHANCE FOR SHOWERS AND AN
ISOLATED THUNDERSTORM CONTINUING INTO THE AFTERNOON HOURS WITH
NEAR TO SLIGHTLY BELOW SEASONAL TEMPERATURES EXPECTED DURING THE
AFTERNOON.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MOST OF THE
PERIOD AND TEMPERATURES.
ZONAL TO SOUTHWEST FLOW GIVES WAY TO NORTHWEST FLOW. THERE ARE
SEVERAL WAVES THAT MOVE THROUGH THE AREA DURING THE PERIOD. THE
FIRST WAVE MOVES INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THERE
WILL BE A CHANCE FOR SOME THUNDERSTORMS. ON FRIDAY A SURFACE LOW
DEVELOPING IN KANSAS WILL LIFT A WARM FRONT NORTH INTO THE FORECAST
AREA. WITH THE FRONT MOVING THROUGH AND THE ANOTHER UPPER WAVE
MOVING INTO THE AREA THERE IS A BETTER CHANCE FOR THUNDERSTORMS.
SOME OF THESE STORMS COULD BE STRONG TO SEVERE.
SATURDAY AND SATURDAY NIGHT THERE ARE WEAK WAVES THAT MOVES THROUGH
BUT LITTLE IN THE WAY TO GET THINGS STARTED SO ANY PRECIPITATION
WILL BE SPOTTY. THE NEXT CHANCE FOR SOME THUNDERSTORMS WILL BE
SUNDAY INTO SUNDAY NIGHT. ANOTHER STRONGER WAVE MOVES INTO THE AREA
AND A COLD FRONT MOVES THROUGH THE AREA SUNDAY AFTERNOON AND
EVENING. THUNDERSTORMS WILL DEVELOP ALONG THE FRONT AS IT MOVES
THROUGH. SOME OF THESE COULD BE SEVERE.
MONDAY AND MONDAY NIGHT THE UPPER WAVE MOVES TO THE EAST AND A
SURFACE HIGH PRESSURE MOVES INTO THE AREA...KEEPING THINGS DRY.
AGAIN TUESDAY INTO TUESDAY NIGHT THERE ARE A FEW WEAK UPPER LEVEL
WAVES THAT MOVE INTO THE PLAINS. MODELS HAVE SOME FAIRLY SPOTTY
PRECIPITATION AROUND THE AREA WITH THESE UPPER LEVEL WAVES. THE GFS
HAS MORE PRECIPITATION AROUND THAN THE ECMWF DOES.
TEMPERATURES WILL BE SOMEWHAT VARIABLE THROUGH THE WEEK. WITH CLOUDS
AROUND ON FRIDAY THE TEMPERATURES WILL BE A BIT COOLER...WARMING
AFTER THE WARM FRONT LIFTS TO THE NORTH FOR SATURDAY AND SUNDAY THEN
COOLING AGAIN AS THE COOL FRONT MOVE THROUGH MONDAY AND TUESDAY AND
COOLING MORE AFTER THE FRONT MOVES THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
1105 UPDATE/949 UPDATE...BRYANT
AVIATION...HEINLEIN
SHORT TERM/419 UPDATE...ROSSI
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
949 PM CDT WED MAY 23 2012
.UPDATE...EVENING UPPER AIR ANALYSIS INDICATES TROUGHING OVER THE
WESTERN CONUS WITH A RIDGE OVER THE EAST. MID AND UPPER LEVEL JET
ENERGY EXTENDS FROM THE WEST-CENTRAL CONUS...SOUTHEAST INTO THE
MID ROCKY MOUNTAIN RANGE AND THEN NORTHEAST ACROSS THE CENTRAL
PLAINS. A ~100KT UPPER LEVEL JET STREAK AND A ~70KT MID LEVEL JET
STREAK IS NOTED ACROSS THE WEST-CENTRAL CONUS AND BEGINNING TO
PUSH INTO THE CENTRAL PLAINS. WATER VAPOR IMAGERY SHOWS A MID
LEVEL SHORT WAVE APPROACHING THE MID ROCKY MOUNTAIN RANGE. AT THE
SURFACE A COLD FRONT EXTENDS FROM NEAR KOMA...TO NEAR KCNK...TO
NEAR KDDC. LOW LEVEL FLOW IS FROM THE THE NORTHEAST ACROSS MUCH OF
OUR CWA AS A RESULT...ALTHOUGH LOCATIONS FROM THAYER COUNTY TO
MITCHELL COUNTY...STILL AHEAD OF THE LOW LEVEL BAROCLINIC
ZONE...REMAIN FROM THE SOUTHEAST. KUEX SHOWS A THIN LINE OF
CONVECTION...ALONG THE LOW LEVEL BAROCLINIC ZONE...EXTENDING FROM
THAYER COUNTY TO MITCHELL COUNTY...BUT ADDITIONAL CONVECTION IS
NOT FIRING FARTHER NORTHWEST ACROSS MUCH OF THE REST OF THE CWA.
SHORT TERM GUIDANCE SUGGESTS SURFACE-BASED CONVECTION WILL REMAIN
POSSIBLE ALONG THE LOW LEVEL BAROCLINIC ZONE THROUGH 04Z OR SO...HOWEVER
THIS ACTIVITY SHOULD DIMINISH THEREAFTER AS DIABATIC HEATING IS COMPLETELY
LOST AND REMNANT FORCING ALONG THE BAROCLINIC ZONE REMAINS FAIRLY WEAK.
THE INDIRECT THERMAL CIRCULATION WITHIN THE LEFT-FRONT QUAD OF
THE APPROACHING MID LEVEL JET STREAK...ALONG WITH CONTINUALLY
INCREASING OMEGA AHEAD OF THE MID LEVEL SHORT WAVE...WILL CONTINUE
TO PROMOTE PRECIPITATION ACROSS MUCH OF THE CWA THROUGH THE
OVERNIGHT HOURS. AT THIS TIME IT APPEARS THE BULK OF THE FORCING
OVERNIGHT WILL BE RELEGATED TO THE NORTHERN HALF OF THE CWA WHICH
IS WHERE MOST OF THE PRECIPITATION WILL BE REALIZED. SPC
MESO-ANALYSIS INDICATES DEEP LAYER MUCAPE VALUES OF AROUND
1000J/KG CURRENTLY IN EXISTENCE ACROSS MUCH OF THE CWA...WITH DEEP
LAYER SHEAR OF AROUND 60KTS. THE COMBINATION OF MODERATE
INSTABILITY AND VERY STRONG DEEP LAYER SHEAR WILL CONTINUE TO
PROMOTE A THREAT OF LARGE HAIL ACROSS MUCH OF THE CWA THROUGH
EARLY MORNING THURSDAY.
WENT AHEAD AND UPDATED THE FORECAST WITH SLIGHT CHANGES MADE TO
HOURLY GIRDS TO BETTER REFLECT CURRENT TRENDS...ESPECIALLY
REGARDING CLOUD COVER. CURRENT POPS ACROSS NORTHERN PORTIONS OF THE
CWA LOOK RIGHT ON FOR TONIGHT AND THUS RAIN CHANCES WERE LEFT AS IS.
&&
.PREV DISCUSSION... /ISSUED 637 PM CDT WED MAY 23 2012/
AVIATION...00Z KGRI TAF. THUNDERSTORM DEVELOPMENT COULD OCCUR
ALONG A SURFACE COLD FRONT CONTINUING TO MOVE TO THE SOUTHEAST.
THIS SURFACE CONVECTION SHOULD REMAIN SOUTHEAST OF THE TERMINAL.
LATER ON TOWARD LATE EVENING...A LOW-LEVEL JET WILL ENCOURAGE
SEVERE THUNDERSTORMS TO DEVELOP AND LINGER INTO THE EARLY
OVERNIGHT HOURS. WIND MAY BE A BIT GUSTY FOR THURSDAY...WITH SOME
SMALL CHANCES OF THUNDERSTORMS. HOWEVER...CHANCES OF PRECIPITATION
ON THURSDAY ARE SMALL ENOUGH TO LEAVE OUT OF THE FORECAST FOR NOW.
PREV DISCUSSION... /ISSUED 419 PM CDT WED MAY 23 2012/
UPDATE...SENT AN UPDATE TO THE FORECAST TO INCLUDE SEVERE
THUNDERSTORM WATCH 293 FOR PORTIONS OF THE FORECAST AREA THROUGH
11 PM CDT. THE GREATEST POTENTIAL FOR ANY SEVERE STORMS WILL
REMAIN WITH AND ALONG EITHER SIDE OF A SLOWLY PROGRESSING COLD
FRONT...WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY
CONCERNS WITH ANY STORMS THAT DO DEVELOP.
PREV DISCUSSION... /ISSUED 400 PM CDT WED MAY 23 2012/
SHORT TERM...A FAIRLY ACTIVE START TO THE FORECAST IS EXPECTED
THIS EVENING AS A COLD FRONT SLOWLY MAKES ITS WAY ACROSS SOUTH
CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...WITH AN ASSOCIATED MID
LEVEL LOW PRESSURE SYSTEM TO THE WEST EXPECTED TO HELP BRING SOME
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE
FORECAST AREA DURING THE OVERNIGHT HOURS TONIGHT.
SHORT TERM MODELS ARE IN MODERATE DISAGREEMENT WITH INITIATION OF
CONVECTION ALONG A PASSING COLD FRONT...CURRENTLY DRAPED FROM NEAR
NORFOLK...ACROSS GRAND ISLAND...SOUTH WESTWARD TOWARDS HOLDREGE.
THIS FRONT HAS BEEN VERY SLOW TO WORK ITS WAY ACROSS THE FORECAST
AREA THIS AFTERNOON...AND SO FAR HAS YET TO PRODUCE ENOUGH FORCING
TO BREAK LOW LEVEL CAP. 12Z NAM AND WRF BOTH DID TRY AND INITIATE
CONVECTION...BUT 18Z NAM AND LATEST HRRR BOTH HOLD OFF ANY
WIDESPREAD SHOWER OR THUNDERSTORM ACTIVITY TILL FORCING FROM MID
LEVEL LOW TO OUR WEST APPROACHES CENTRAL NEBRASKA AROUND MIDNIGHT.
THAT BEING SAID...INGREDIENTS ARE IN PLACE...AS LATEST MESO
ANALYSIS SHOWS A FINGER OF 2000+ J/KG OF CAPE ACROSS THE LOCAL
AREA NEAR THE SLOWLY PROGRESSING FRONT...AND LITTLE INHIBITION AS
WELL AS DEVELOPING CU FIELD IN SATELLITE. PER CONSENSUS AMONG
MODELS...DID BACK OFF ON INITIATION OF CONVECTION THIS
AFTERNOON...BUT INSERTED MENTION OF SEVERE STORMS AFTER 00Z...AS
COMBINATION OF SHEAR AND INSTABILITY SHOULD BE SUFFICIENT FOR SOME
SUPERCELLS TO DEVELOP IF INITIATION CAN BE REALIZED NEAR THE
FRONT.
BEHIND THE FRONT...AS THE MID LEVEL SHORTWAVE APPROACHES THE
REGION...BROADER SCALE FORCING SHOULD BE AMPLE ENOUGH TO DEVELOP
WIDESPREAD CONVECTION ACROSS THE LOCAL AREA BY AROUND
MIDNIGHT...CONTINUING INTO THE OVERNIGHT HOURS...SO THE POTENTIAL
FOR SEVERE HAIL AND STRONG WINDS REMAIN A CONCERN.
THEREAFTER...THE ATMOSPHERE SHOULD BEGIN TO STABILIZE BEHIND THE
DEPARTING MID LEVEL WAVE...WITH A SMALL CHANCE FOR SHOWERS AND AN
ISOLATED THUNDERSTORM CONTINUING INTO THE AFTERNOON HOURS WITH
NEAR TO SLIGHTLY BELOW SEASONAL TEMPERATURES EXPECTED DURING THE
AFTERNOON.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MOST OF THE
PERIOD AND TEMPERATURES.
ZONAL TO SOUTHWEST FLOW GIVES WAY TO NORTHWEST FLOW. THERE ARE
SEVERAL WAVES THAT MOVE THROUGH THE AREA DURING THE PERIOD. THE
FIRST WAVE MOVES INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THERE
WILL BE A CHANCE FOR SOME THUNDERSTORMS. ON FRIDAY A SURFACE LOW
DEVELOPING IN KANSAS WILL LIFT A WARM FRONT NORTH INTO THE FORECAST
AREA. WITH THE FRONT MOVING THROUGH AND THE ANOTHER UPPER WAVE
MOVING INTO THE AREA THERE IS A BETTER CHANCE FOR THUNDERSTORMS.
SOME OF THESE STORMS COULD BE STRONG TO SEVERE.
SATURDAY AND SATURDAY NIGHT THERE ARE WEAK WAVES THAT MOVES THROUGH
BUT LITTLE IN THE WAY TO GET THINGS STARTED SO ANY PRECIPITATION
WILL BE SPOTTY. THE NEXT CHANCE FOR SOME THUNDERSTORMS WILL BE
SUNDAY INTO SUNDAY NIGHT. ANOTHER STRONGER WAVE MOVES INTO THE AREA
AND A COLD FRONT MOVES THROUGH THE AREA SUNDAY AFTERNOON AND
EVENING. THUNDERSTORMS WILL DEVELOP ALONG THE FRONT AS IT MOVES
THROUGH. SOME OF THESE COULD BE SEVERE.
MONDAY AND MONDAY NIGHT THE UPPER WAVE MOVES TO THE EAST AND A
SURFACE HIGH PRESSURE MOVES INTO THE AREA...KEEPING THINGS DRY.
AGAIN TUESDAY INTO TUESDAY NIGHT THERE ARE A FEW WEAK UPPER LEVEL
WAVES THAT MOVE INTO THE PLAINS. MODELS HAVE SOME FAIRLY SPOTTY
PRECIPITATION AROUND THE AREA WITH THESE UPPER LEVEL WAVES. THE GFS
HAS MORE PRECIPITATION AROUND THAN THE ECMWF DOES.
TEMPERATURES WILL BE SOMEWHAT VARIABLE THROUGH THE WEEK. WITH CLOUDS
AROUND ON FRIDAY THE TEMPERATURES WILL BE A BIT COOLER...WARMING
AFTER THE WARM FRONT LIFTS TO THE NORTH FOR SATURDAY AND SUNDAY THEN
COOLING AGAIN AS THE COOL FRONT MOVE THROUGH MONDAY AND TUESDAY AND
COOLING MORE AFTER THE FRONT MOVES THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
946 UPDATE...BRYANT
AVIATION...HEINLEIN
SHORT/419 UPDATE...ROSSI
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
637 PM CDT WED MAY 23 2012
.AVIATION...00Z KGRI TAF. THUNDERSTORM DEVELOPMENT COULD OCCUR
ALONG A SURFACE COLD FRONT CONTINUING TO MOVE TO THE SOUTHEAST.
THIS SURFACE CONVECTION SHOULD REMAIN SOUTHEAST OF THE TERMINAL.
LATER ON TOWARD LATE EVENING...A LOW-LEVEL JET WILL ENCOURAGE
SEVERE THUNDERSTORMS TO DEVELOP AND LINGER INTO THE EARLY
OVERNIGHT HOURS. WIND MAY BE A BIT GUSTY FOR THURSDAY...WITH SOME
SMALL CHANCES OF THUNDERSTORMS. HOWEVER...CHANCES OF PRECIPITATION
ON THURSDAY ARE SMALL ENOUGH TO LEAVE OUT OF THE FORECAST FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 419 PM CDT WED MAY 23 2012/
UPDATE...SENT AN UPDATE TO THE FORECAST TO INCLUDE SEVERE
THUNDERSTORM WATCH 293 FOR PORTIONS OF THE FORECAST AREA THROUGH
11 PM CDT. THE GREATEST POTENTIAL FOR ANY SEVERE STORMS WILL
REMAIN WITH AND ALONG EITHER SIDE OF A SLOWLY PROGRESSING COLD
FRONT...WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY
CONCERNS WITH ANY STORMS THAT DO DEVELOP.
PREV DISCUSSION... /ISSUED 400 PM CDT WED MAY 23 2012/
SHORT TERM...A FAIRLY ACTIVE START TO THE FORECAST IS EXPECTED
THIS EVENING AS A COLD FRONT SLOWLY MAKES ITS WAY ACROSS SOUTH
CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...WITH AN ASSOCIATED MID
LEVEL LOW PRESSURE SYSTEM TO THE WEST EXPECTED TO HELP BRING SOME
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE
FORECAST AREA DURING THE OVERNIGHT HOURS TONIGHT.
SHORT TERM MODELS ARE IN MODERATE DISAGREEMENT WITH INITIATION OF
CONVECTION ALONG A PASSING COLD FRONT...CURRENTLY DRAPED FROM NEAR
NORFOLK...ACROSS GRAND ISLAND...SOUTH WESTWARD TOWARDS HOLDREGE.
THIS FRONT HAS BEEN VERY SLOW TO WORK ITS WAY ACROSS THE FORECAST
AREA THIS AFTERNOON...AND SO FAR HAS YET TO PRODUCE ENOUGH FORCING
TO BREAK LOW LEVEL CAP. 12Z NAM AND WRF BOTH DID TRY AND INITIATE
CONVECTION...BUT 18Z NAM AND LATEST HRRR BOTH HOLD OFF ANY
WIDESPREAD SHOWER OR THUNDERSTORM ACTIVITY TILL FORCING FROM MID
LEVEL LOW TO OUR WEST APPROACHES CENTRAL NEBRASKA AROUND MIDNIGHT.
THAT BEING SAID...INGREDIENTS ARE IN PLACE...AS LATEST MESO
ANALYSIS SHOWS A FINGER OF 2000+ J/KG OF CAPE ACROSS THE LOCAL
AREA NEAR THE SLOWLY PROGRESSING FRONT...AND LITTLE INHIBITION AS
WELL AS DEVELOPING CU FIELD IN SATELLITE. PER CONSENSUS AMONG
MODELS...DID BACK OFF ON INITIATION OF CONVECTION THIS
AFTERNOON...BUT INSERTED MENTION OF SEVERE STORMS AFTER 00Z...AS
COMBINATION OF SHEAR AND INSTABILITY SHOULD BE SUFFICIENT FOR SOME
SUPERCELLS TO DEVELOP IF INITIATION CAN BE REALIZED NEAR THE
FRONT.
BEHIND THE FRONT...AS THE MID LEVEL SHORTWAVE APPROACHES THE
REGION...BROADER SCALE FORCING SHOULD BE AMPLE ENOUGH TO DEVELOP
WIDESPREAD CONVECTION ACROSS THE LOCAL AREA BY AROUND
MIDNIGHT...CONTINUING INTO THE OVERNIGHT HOURS...SO THE POTENTIAL
FOR SEVERE HAIL AND STRONG WINDS REMAIN A CONCERN.
THEREAFTER...THE ATMOSPHERE SHOULD BEGIN TO STABILIZE BEHIND THE
DEPARTING MID LEVEL WAVE...WITH A SMALL CHANCE FOR SHOWERS AND AN
ISOLATED THUNDERSTORM CONTINUING INTO THE AFTERNOON HOURS WITH
NEAR TO SLIGHTLY BELOW SEASONAL TEMPERATURES EXPECTED DURING THE
AFTERNOON.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MOST OF THE
PERIOD AND TEMPERATURES.
ZONAL TO SOUTHWEST FLOW GIVES WAY TO NORTHWEST FLOW. THERE ARE
SEVERAL WAVES THAT MOVE THROUGH THE AREA DURING THE PERIOD. THE
FIRST WAVE MOVES INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THERE
WILL BE A CHANCE FOR SOME THUNDERSTORMS. ON FRIDAY A SURFACE LOW
DEVELOPING IN KANSAS WILL LIFT A WARM FRONT NORTH INTO THE FORECAST
AREA. WITH THE FRONT MOVING THROUGH AND THE ANOTHER UPPER WAVE
MOVING INTO THE AREA THERE IS A BETTER CHANCE FOR THUNDERSTORMS.
SOME OF THESE STORMS COULD BE STRONG TO SEVERE.
SATURDAY AND SATURDAY NIGHT THERE ARE WEAK WAVES THAT MOVES THROUGH
BUT LITTLE IN THE WAY TO GET THINGS STARTED SO ANY PRECIPITATION
WILL BE SPOTTY. THE NEXT CHANCE FOR SOME THUNDERSTORMS WILL BE
SUNDAY INTO SUNDAY NIGHT. ANOTHER STRONGER WAVE MOVES INTO THE AREA
AND A COLD FRONT MOVES THROUGH THE AREA SUNDAY AFTERNOON AND
EVENING. THUNDERSTORMS WILL DEVELOP ALONG THE FRONT AS IT MOVES
THROUGH. SOME OF THESE COULD BE SEVERE.
MONDAY AND MONDAY NIGHT THE UPPER WAVE MOVES TO THE EAST AND A
SURFACE HIGH PRESSURE MOVES INTO THE AREA...KEEPING THINGS DRY.
AGAIN TUESDAY INTO TUESDAY NIGHT THERE ARE A FEW WEAK UPPER LEVEL
WAVES THAT MOVE INTO THE PLAINS. MODELS HAVE SOME FAIRLY SPOTTY
PRECIPITATION AROUND THE AREA WITH THESE UPPER LEVEL WAVES. THE GFS
HAS MORE PRECIPITATION AROUND THAN THE ECMWF DOES.
TEMPERATURES WILL BE SOMEWHAT VARIABLE THROUGH THE WEEK. WITH CLOUDS
AROUND ON FRIDAY THE TEMPERATURES WILL BE A BIT COOLER...WARMING
AFTER THE WARM FRONT LIFTS TO THE NORTH FOR SATURDAY AND SUNDAY THEN
COOLING AGAIN AS THE COOL FRONT MOVE THROUGH MONDAY AND TUESDAY AND
COOLING MORE AFTER THE FRONT MOVES THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION...HEINLEIN
SHORT TERM/UPDATE...ROSSI
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1214 AM CDT TUE MAY 22 2012
.AVIATION...06Z KGRI TAF. VFR CEILING/VISIBILITY WILL HOLD FIRM
THROUGH THE PERIOD...WITH NOTHING MORE THAN VARYING DEGREES OF
PASSING MID AND HIGH LEVEL CLOUDS. HOWEVER...STRONG SOUTHERLY WIND
WILL BE AN ISSUE DURING THE PERIOD. INITIALLY BEFORE
SUNRISE...SUSTAINED SPEEDS WILL AVERAGE NEAR 14KT...BUT A STEADY
RAMP-UP WILL TAKE PLACE DURING THE DAY...WITH SUSTAINED SPEEDS
TOPPING OUT NEAR 23KT AND GUST POTENTIAL TO NEAR 32KT...WHICH IS A
SLIGHT INCREASE OVER SPEEDS INDICATED IN THE PREVIOUS TAF
ISSUANCE. EVEN AFTER NIGHTFALL TUESDAY EVENING...GUSTS TO TO
AROUND 26KT WILL PERSIST. LOOKING ABOVE THE SURFACE...A
STRENGTHENING LOW LEVEL JET WILL RESULT IN ENOUGH SPEED SHEAR IN
THE LOWEST 1500 FT AGL TO JUSTIFY A MENTION OF LOW LEVEL WIND SHEAR
THROUGH THE FIRST SEVERAL HOURS OF THE PERIOD. FINALLY...WILL
INSERT A VICINITY SHOWER MENTION FOR THE FIRST SEVERAL HOURS OF
THE PERIOD AS WELL TO ACCOUNT FOR THE POSSIBILITY OF A BRIEF
SHOWER MOVING IN FROM THE NORTHWEST.
&&
.PREV DISCUSSION... /ISSUED 1148 PM CDT MON MAY 21 2012/
UPDATE...EVENING UPPER AIR ANALYSIS INDICATES RIDGING OVER THE
WESTERN CONUS WITH TROUGHING OVER THE EAST. MID AND UPPER LEVEL
FLOW OVER THE CENTRAL PLAINS REMAIN FROM THE NORTHWEST AS A
RESULT. THAT BEING SAID...THE PRIMARY AXIS OF MID AND UPPER LEVEL
JET ENERGY IS RELEGATED TO THE NORTHWESTERN CONUS THUS LEAVING
TROPOSPHERIC FLOW FAIRLY WEAK OVER OUR AREA...WITH THE ONLY
EXCEPTION BEING CLOSER TO 850MB WHERE A 20-30KT LOW LEVEL JET
STREAK IS NOTED EXTENDING FROM WESTERN KANSAS INTO WESTERN
NEBRASKA. WATER VAPOR IMAGERY SHOWS INCREASED VALUES OF MID LEVEL
MOISTURE FLOWING INTO THE WESTERN CONUS FROM THE PACIFIC...SOME OF
WHICH IS BEGINNING TO SPILL OVER THE WESTERN CONUS RIDGE THUS
RESULTING IN INCREASING MID TO HIGH LEVEL CLOUDS ACROSS THE
NORTHERN AND CENTRAL PLAINS. WATER VAPOR IMAGERY ALSO SHOW A MID
LEVEL LOW TO THE SOUTHEAST OF THE ALEUTIAN ISLANDS...WITH A MID
LEVEL SHORT WAVE PIVOTING TO THE SOUTH OF THE LOW. AT THE SURFACE
A RIDGE OF HIGH PRESSURE IS NOTED OVER THE MISSISSIPPI
VALLEY WITH TROUGHING OVER THE FRONT RANGE...THUS HELPING PROMOTE
SOUTH/SOUTHEASTERLY LOW LEVEL FLOW ACROSS THE CENTRAL PLAINS.
KUEX CONTINUES TO INDICATE THE LEADING EDGE OF CONVECTIVE ACTIVITY
EXTENDING FROM NEAR KODX TO NEAR BEAVER CITY AND MOVING SOUTHEAST. THIS
ACTIVITY IS LIKELY BEING REINFORCED BY LOW LEVEL THERMAL ADVECTION
ALONG THE AXIS OF THE LOW LEVEL JET CURRENTLY NEAR THE AREA. SHORT
TERM GUIDANCE PER THE RAP AND NAM SUGGEST THIS LOW LEVEL JET WILL
PUSH EAST AND BECOME MORE ORIENTED FROM THE SOUTHWEST TO NORTHEAST
ACROSS OUR AREA THROUGH 12Z. GIVEN THIS...IT IS AT LEAST POSSIBLE
ISOLATED TO PERHAPS SCATTERED PRECIPITATION WILL PERSIST OVER
PORTIONS OF THE CWA THROUGH THE OVERNIGHT HOURS. SPC
MESO-ANALYSIS SUGGESTS THE PRIMARY INSTABILITY AXIS EXISTS TO OUR
WEST OVER THE HIGH PLAINS...BUT IT IS POSSIBLE THIS INSTABILITY
AXIS...WITH PERHAPS AROUND 100J/KG DEEP LAYER MUCAPE...COULD
SPREAD EAST MORE INTO OUR AREA AS MOISTURE ADVECTION ALONG THE LOW
LEVEL JET AXIS ALSO PUSHES INTO OUR AREA. GIVEN ALL THIS...WENT
AHEAD AND EXTENDED SLIGHT CHANCE POPS ACROSS ROUGHLY THE
NORTHWESTERN HALF OF THE CWA THROUGH 12Z...WHICH MATCHES UP FAIRLY
CLOSELY WITH THE ANTICIPATED POSITION OF THE LOW LEVEL JET AXIS
THROUGH 12Z. ALTHOUGH INSTABILITY IS EXTREMELY LIMITED OVER OUR
AREA AT THIS HOUR...GIVEN THE POSSIBILITY OF SOMEWHAT INCREASING
INSTABILITY ACROSS OUR AREA...WENT AHEAD AND ALSO KEPT THE
ISOLATED THUNDER MENTION IN THE FORECAST FOR TONIGHT.
PREV DISCUSSION... /ISSUED 1021 PM CDT MON MAY 21 2012/
UPDATE...UPDATED THE FORECAST THIS EVENING FOR SOME POSSIBLE
LIGHT PRECIPITATION IN OUR FAR WEST/NORTHWEST CWA AS THUNDERSTORMS
TO THE WEST DWINDLE. LITTLE SHEAR AND INSTABILITY TO HELP SUPPORT
THESE CELLS AND THEY SHOULD DIE OUT IN THE NEXT FEW HOURS.
PREV DISCUSSION... /ISSUED 403 PM CDT MON MAY 21 2012/
SHORT TERM...TONIGHT AND TOMORROW.
A QUICK UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL CLOSED LOW
PUSHING OFF THE EAST COAST WHILE THE TROUGH AXIS REMAINS ORIENTED
ACROSS THE MISSISSIPPI VALLEY REGION. BUILDING IN ACROSS THE WESTERN
HALF OF THE CONUS...AN UPPER LEVEL RIDGE HAS BEGUN TO DOMINATE MUCH
OF THE ROCKY MOUNTAIN WEATHER. SEVERAL WEAK SHORT WAVE PERTURBATIONS
REMAIN IN THE DOMINATE FLOW...INCLUDING ONE ACROSS THE FRONT RANGE.
A SURGE OF MOISTURE IN THE MID LEVELS HAS POOLED UNDER AN AREA OF
HIGH PRESSURE ACROSS THE TEXAS PANHANDLE...BUT SOME SCANT AMOUNTS
HAVE SURGED AS FAR NORTH AS SOUTH DAKOTA ACROSS WESTERN NEBRASKA. AT
THE SURFACE...A LARGE AREA OF HIGH PRESSURE HAS LAGGED ACROSS THE
CENTRAL CONUS STRETCHING FROM CANADA TO TEXAS...WHILE WEAK LOW
PRESSURE HAS BEGUN TO DEVELOP ACROSS THE FRONT RANGE.
BEGINNING THE SHORT TERM...THE PLAINS REMAIN UNDER THE INFLUENCE OF
THE INCOMING RIDGE AND ASSOCIATED SURFACE HIGH. THIS HIGH PRESSURE
SYSTEM WILL BEGIN TO SHIFT EASTWARD AS THE MAIN FOCUS OF THE SHORT
TERM SHIFTS TO THE INCOMING SURFACE LOW/TROUGH.
A FEW CONCERNS DURING THE OVERNIGHT PERIOD WILL BE THE INCREASE IN
THE LOW LEVEL JET OVERNIGHT. MODELS INCREASE 850 MB WINDS TO NEAR 40
KTS OVERNIGHT...WITH THE GFS AND THE ECMWF JET LOCATIONS ACROSS THE
WESTERN HALF OF THE STATE AND THE NAM A BIT FURTHER EAST. BOTH THE
NAM AND THE GFS SOLUTION GENERATE SOME POPS WITH THE LOW LEVEL
JET...HOWEVER...THE NAM MODEL REMAINS FURTHER WEST...WHILE THE GFS
GENERATES POPS ACROSS THE FORECAST AREA. THE 4 KM WRF MODEL DOES NOT
PICK UP ON ANY SUGGESTION OF POTENTIAL POPS DURING THE OVERNIGHT
PERIOD. DECIDED TO LEAVE THE OVERNIGHT PERIOD DRY...BUT THIS COULD
BE A CONCERN GIVEN THE LOW LEVEL JET AXIS.
LEADING TOWARDS THE DAYTIME HOURS ON TUESDAY...THE SURFACE TROUGH WILL
CONTINUE TO PUSH EASTWARD...HELPING TIGHTEN THE PRESSURE GRADIENT
ACROSS THE PLAINS. AS A RESULT...INCREASED SOUTH WINDS WILL BE
PREVALENT DURING THE LATE MORNING AND AFTERNOON HOURS ON TUESDAY.
MODELS TRENDS HAVE REMAINED FAIRLY CONSISTENT BETWEEN
RUNS...ALTHOUGH MODEL GUIDANCE AS BEEN TRENDING DOWN SINCE
PREVIOUS RUNS. GIVEN THAT MODELS AND GUIDANCE REMAIN ONLY MARGINAL
WIND ADVISORY AT BEST IN ONLY A FEW LOCATIONS...DECIDED TO OPT OUT
OF ISSUING A WIND ADVISORY AT THIS POINT.
REGARDING TEMPERATURES ON TUESDAY...AS THE UPPER LEVEL RIDGE BUILDS
ACROSS THE PLAINS AND BOUNDARY LAYER MIXING IS EXPECTED TO AT LEAST
850 MB IF NOT 800 MB...SEE NO REASON WHY WE CANNOT TAP INTO SOME
WARM TEMPERATURES. THE NAM AND THE ECMWF REMAIN IN GOOD AGREEMENT
WITH A TEMPERATURE GRADIENT FROM POSSIBLY THE LOW 90S OUT WEST TO
LOW 80S IN THE EAST...THUS SUGGESTING A GRADIENT OF ABOUT 7 TO 10
DEGREES. THE GFS SOLUTION REMAINS THE OUTLIER WITH A MUCH COOLER
GRADIENT WITH MID 80S OUT WEST AND MID 70S EAST. DECIDED TO LEAN
MORE WITH THE NAM/EC SOLUTION ALTHOUGH PORTIONS FARTHER WEST COULD
BE A BIT WARMER AND PORTIONS FARTHER EAST COULD BE A BIT COOLER THAN
FORECAST.
LONG TERM...00Z WED THROUGH MONDAY. OFF AND ON CHANCES FOR
PRECIPITATION DURING THE EXTENDED WILL BE MAIN CONCERN AS PATTERN
BECOMES MORE ACTIVE.
WEAK MID LEVEL RIDGE SHOULD BEGIN TO SLIDE TO OUR EAST OVERNIGHT
TUESDAY AND LOW AMPLITUDE TROUGH BEGINS TO PUSH INTO THE NW U.S.
FIRST WAVE OF ENERGY WILL KICK OUT AND PUSH A COLD FRONT INTO THE
CENTRAL PLAINS DURING THE DAYTIME ON WED. SHOULD BE ENTERING THE NW
PART OF THE CWA BY SUNRISE WED AND PUSH THROUGH DURING THE DAY. NAM
MORE PROGRESSIVE THAN THE GFS WITH THIS FRONT. ALL MODELS SHOWING
DECENT CAP OVER THE SE HALF OF THE CWA DURING THE AFTERNOON AND
BANKING ON THIS FEATURE TO KEEP THUNDERSTORMS AT BAY DURING THE DAY.
CHANCES INCREASE ESPECIALLY IN THE NORTHERN PART OF THE CWA WED
EVENING AND OVERNIGHT AS MID LEVEL WAVE ROTATES THROUGH HELPING COOL
OFF MID LEVEL TEMPS ESPECIALLY IN THE NORTH. GFS AND OLD EC MODELS
DO SHOW THE BETTER JET SUPPORT TO BE JUST A LITTLE NORTH OF US WITH
RIGHT ENTRANCE AND LEFT EXIT REGIONS OF COUPLED JET FAVORING NW NEB.
MODELS ALSO SHOWING BEST MID LEVEL FRONTOGENESIS IN THIS AREA. WILL
WAIT TO GET A LOOK AT THE 12Z EC RUN BUT UNLESS IT SHOWS SOMETHING
DIFFERENT WILL KEEP WITH PREVIOUS THINKING OF BEST CHANCES FOR
THUNDERSTORMS IN THE NORTHWEST CWA AND DRY IN OUR FAR SOUTHEAST AS
CAP EXPECTED TO HOLD AND EVEN STRENGTHEN IN THAT AREA OVERNIGHT. IN
REGARDS TO SEVERE POTENTIAL...DEEP LAYER SHEAR AND MU CAPE WOULD
SUPPORT SOME SEVERE IN THE AREA.
THURSDAY/THUR NIGHT NOT REAL CLEAR CUT AS MODELS DIFFERING ON PRECIP
CHANCES. INITIAL THOUGHT IS THAT WE WON`T SEE MUCH DURING THE DAY
AND THEN CHANCES INCREASE SOME OVERNIGHT AS LOW LEVEL INCREASES.
HOWEVER WILL LEAVE AT LEAST A SMALL CHANCE IN THE NORTH DURING THE
DAYTIME. AS FIRST WAVE EJECTS TO OUR NORTH...ANOTHER DEEPER MID
LEVEL LOW PRESSURE SYSTEM IS PROGGED TO DIG FROM THE PACIFIC NW ON
THURSDAY INTO SOUTHERN NEVADA BY SATURDAY BEFORE LIFTING NORTH INTO
SOUTHERN MANITOBA BY MONDAY NIGHT. THIS TRACK IS MAINLY BASED OFF
THE EC AND IF IT HOLDS TRUE...WE SHOULD BE DRY DURING THE DAYTIME ON
FRIDAY WITH SHORT WAVE RIDGING. STILL LINGERING CHANCES FOR RAIN
FRIDAY NIGHT INTO SATURDAY NIGHT WITH WARM FRONT LIFTING NORTH AND
CYCLONIC FLOW IN THE UPPER LEVELS. SUNDAY COULD BE INTERESTING AS
COLD FRONT SWEEPS THROUGH DURING THE AFTERNOON. EARLY LOOK AT CAPE
AND SHEAR WOULD POINT TO SEVERE WEATHER CHANCE BUT AS USUAL THAT
WILL DEPEND ON TIMING OF A SYSTEM WHICH IS STILL SEVERAL DAYS AWAY.
AS FAR AS HIGH TEMPERATURES GO...WE WILL SEE SOME VARIATION AS
FRONTAL BOUNDARIES PUSH THROUGH...WITH THINGS A LITTLE COOLER ON
WED IN THE NORTH CWA AND THEN OVER THE ENTIRE AREA THURS AND FRI
BEFORE IT WARMS UP AGAIN ON SAT INTO SUNDAY AHEAD OF NEXT COLD
FRONT. NEXT MONDAY SHOULD ONCE AGAIN BE A LITTLE COOLER BEHIND THE
FRONT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION...PFANNKUCH
1148 PM UPDATE...BRYANT
1021 PM UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...EWALD
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1148 PM CDT MON MAY 21 2012
.UPDATE...EVENING UPPER AIR ANALYSIS INDICATES RIDGING OVER THE
WESTERN CONUS WITH TROUGHING OVER THE EAST. MID AND UPPER LEVEL
FLOW OVER THE CENTRAL PLAINS REMAIN FROM THE NORTHWEST AS A
RESULT. THAT BEING SAID...THE PRIMARY AXIS OF MID AND UPPER LEVEL
JET ENERGY IS RELEGATED TO THE NORTHWESTERN CONUS THUS LEAVING
TROPOSPHERIC FLOW FAIRLY WEAK OVER OUR AREA...WITH THE ONLY
EXCEPTION BEING CLOSER TO 850MB WHERE A 20-30KT LOW LEVEL JET
STREAK IS NOTED EXTENDING FROM WESTERN KANSAS INTO WESTERN
NEBRASKA. WATER VAPOR IMAGERY SHOWS INCREASED VALUES OF MID LEVEL
MOISTURE FLOWING INTO THE WESTERN CONUS FROM THE PACIFIC...SOME OF
WHICH IS BEGINNING TO SPILL OVER THE WESTERN CONUS RIDGE THUS
RESULTING IN INCREASING MID TO HIGH LEVEL CLOUDS ACROSS THE
NORTHERN AND CENTRAL PLAINS. WATER VAPOR IMAGERY ALSO SHOW A MID
LEVEL LOW TO THE SOUTHEAST OF THE ALEUTIAN ISLANDS...WITH A MID
LEVEL SHORT WAVE PIVOTING TO THE SOUTH OF THE LOW. AT THE SURFACE
A RIDGE OF HIGH PRESSURE IS NOTED OVER THE MISSISSIPPI
VALLEY WITH TROUGHING OVER THE FRONT RANGE...THUS HELPING PROMOTE
SOUTH/SOUTHEASTERLY LOW LEVEL FLOW ACROSS THE CENTRAL PLAINS.
KUEX CONTINUES TO INDICATE THE LEADING EDGE OF CONVECTIVE ACTIVITY
EXTENDING FROM NEAR KODX TO NEAR BEAVER CITY AND MOVING SOUTHEAST. THIS
ACTIVITY IS LIKELY BEING REINFORCED BY LOW LEVEL THERMAL ADVECTION
ALONG THE AXIS OF THE LOW LEVEL JET CURRENTLY NEAR THE AREA. SHORT
TERM GUIDANCE PER THE RAP AND NAM SUGGEST THIS LOW LEVEL JET WILL
PUSH EAST AND BECOME MORE ORIENTED FROM THE SOUTHWEST TO NORTHEAST
ACROSS OUR AREA THROUGH 12Z. GIVEN THIS...IT IS AT LEAST POSSIBLE
ISOLATED TO PERHAPS SCATTERED PRECIPITATION WILL PERSIST OVER
PORTIONS OF THE CWA THROUGH THE OVERNIGHT HOURS. SPC
MESO-ANALYSIS SUGGESTS THE PRIMARY INSTABILITY AXIS EXISTS TO OUR
WEST OVER THE HIGH PLAINS...BUT IT IS POSSIBLE THIS INSTABILITY
AXIS...WITH PERHAPS AROUND 100J/KG DEEP LAYER MUCAPE...COULD
SPREAD EAST MORE INTO OUR AREA AS MOISTURE ADVECTION ALONG THE LOW
LEVEL JET AXIS ALSO PUSHES INTO OUR AREA. GIVEN ALL THIS...WENT
AHEAD AND EXTENDED SLIGHT CHANCE POPS ACROSS ROUGHLY THE
NORTHWESTERN HALF OF THE CWA THROUGH 12Z...WHICH MATCHES UP FAIRLY
CLOSELY WITH THE ANTICIPATED POSITION OF THE LOW LEVEL JET AXIS
THROUGH 12Z. ALTHOUGH INSTABILITY IS EXTREMELY LIMITED OVER OUR
AREA AT THIS HOUR...GIVEN THE POSSIBILITY OF SOMEWHAT INCREASING
INSTABILITY ACROSS OUR AREA...WENT AHEAD AND ALSO KEPT THE
ISOLATED THUNDER MENTION IN THE FORECAST FOR TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 1021 PM CDT MON MAY 21 2012/
UPDATE...UPDATED THE FORECAST THIS EVENING FOR SOME POSSIBLE
LIGHT PRECIPITATION IN OUR FAR WEST/NORTHWEST CWA AS THUNDERSTORMS
TO THE WEST DWINDLE. LITTLE SHEAR AND INSTABILITY TO HELP SUPPORT
THESE CELLS AND THEY SHOULD DIE OUT IN THE NEXT FEW HOURS.
PREV DISCUSSION... /ISSUED 700 PM CDT MON MAY 21 2012/
AVIATION...00Z KGRI TAF. VFR CONDITIONS WITH WIND KICKING UP ON
TUESDAY. ANY STORMS TO THE WEST SHOULD DIE OFF BEFORE REACHING THE
TERMINAL TONIGHT.
PREV DISCUSSION... /ISSUED 403 PM CDT MON MAY 21 2012/
SHORT TERM...TONIGHT AND TOMORROW.
A QUICK UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL CLOSED LOW
PUSHING OFF THE EAST COAST WHILE THE TROUGH AXIS REMAINS ORIENTED
ACROSS THE MISSISSIPPI VALLEY REGION. BUILDING IN ACROSS THE WESTERN
HALF OF THE CONUS...AN UPPER LEVEL RIDGE HAS BEGUN TO DOMINATE MUCH
OF THE ROCKY MOUNTAIN WEATHER. SEVERAL WEAK SHORT WAVE PERTURBATIONS
REMAIN IN THE DOMINATE FLOW...INCLUDING ONE ACROSS THE FRONT RANGE.
A SURGE OF MOISTURE IN THE MID LEVELS HAS POOLED UNDER AN AREA OF
HIGH PRESSURE ACROSS THE TEXAS PANHANDLE...BUT SOME SCANT AMOUNTS
HAVE SURGED AS FAR NORTH AS SOUTH DAKOTA ACROSS WESTERN NEBRASKA. AT
THE SURFACE...A LARGE AREA OF HIGH PRESSURE HAS LAGGED ACROSS THE
CENTRAL CONUS STRETCHING FROM CANADA TO TEXAS...WHILE WEAK LOW
PRESSURE HAS BEGUN TO DEVELOP ACROSS THE FRONT RANGE.
BEGINNING THE SHORT TERM...THE PLAINS REMAIN UNDER THE INFLUENCE OF
THE INCOMING RIDGE AND ASSOCIATED SURFACE HIGH. THIS HIGH PRESSURE
SYSTEM WILL BEGIN TO SHIFT EASTWARD AS THE MAIN FOCUS OF THE SHORT
TERM SHIFTS TO THE INCOMING SURFACE LOW/TROUGH.
A FEW CONCERNS DURING THE OVERNIGHT PERIOD WILL BE THE INCREASE IN
THE LOW LEVEL JET OVERNIGHT. MODELS INCREASE 850 MB WINDS TO NEAR 40
KTS OVERNIGHT...WITH THE GFS AND THE ECMWF JET LOCATIONS ACROSS THE
WESTERN HALF OF THE STATE AND THE NAM A BIT FURTHER EAST. BOTH THE
NAM AND THE GFS SOLUTION GENERATE SOME POPS WITH THE LOW LEVEL
JET...HOWEVER...THE NAM MODEL REMAINS FURTHER WEST...WHILE THE GFS
GENERATES POPS ACROSS THE FORECAST AREA. THE 4 KM WRF MODEL DOES NOT
PICK UP ON ANY SUGGESTION OF POTENTIAL POPS DURING THE OVERNIGHT
PERIOD. DECIDED TO LEAVE THE OVERNIGHT PERIOD DRY...BUT THIS COULD
BE A CONCERN GIVEN THE LOW LEVEL JET AXIS.
LEADING TOWARDS THE DAYTIME HOURS ON TUESDAY...THE SURFACE TROUGH WILL
CONTINUE TO PUSH EASTWARD...HELPING TIGHTEN THE PRESSURE GRADIENT
ACROSS THE PLAINS. AS A RESULT...INCREASED SOUTH WINDS WILL BE
PREVALENT DURING THE LATE MORNING AND AFTERNOON HOURS ON TUESDAY.
MODELS TRENDS HAVE REMAINED FAIRLY CONSISTENT BETWEEN
RUNS...ALTHOUGH MODEL GUIDANCE AS BEEN TRENDING DOWN SINCE
PREVIOUS RUNS. GIVEN THAT MODELS AND GUIDANCE REMAIN ONLY MARGINAL
WIND ADVISORY AT BEST IN ONLY A FEW LOCATIONS...DECIDED TO OPT OUT
OF ISSUING A WIND ADVISORY AT THIS POINT.
REGARDING TEMPERATURES ON TUESDAY...AS THE UPPER LEVEL RIDGE BUILDS
ACROSS THE PLAINS AND BOUNDARY LAYER MIXING IS EXPECTED TO AT LEAST
850 MB IF NOT 800 MB...SEE NO REASON WHY WE CANNOT TAP INTO SOME
WARM TEMPERATURES. THE NAM AND THE ECMWF REMAIN IN GOOD AGREEMENT
WITH A TEMPERATURE GRADIENT FROM POSSIBLY THE LOW 90S OUT WEST TO
LOW 80S IN THE EAST...THUS SUGGESTING A GRADIENT OF ABOUT 7 TO 10
DEGREES. THE GFS SOLUTION REMAINS THE OUTLIER WITH A MUCH COOLER
GRADIENT WITH MID 80S OUT WEST AND MID 70S EAST. DECIDED TO LEAN
MORE WITH THE NAM/EC SOLUTION ALTHOUGH PORTIONS FARTHER WEST COULD
BE A BIT WARMER AND PORTIONS FARTHER EAST COULD BE A BIT COOLER THAN
FORECAST.
LONG TERM...00Z WED THROUGH MONDAY. OFF AND ON CHANCES FOR
PRECIPITATION DURING THE EXTENDED WILL BE MAIN CONCERN AS PATTERN
BECOMES MORE ACTIVE.
WEAK MID LEVEL RIDGE SHOULD BEGIN TO SLIDE TO OUR EAST OVERNIGHT
TUESDAY AND LOW AMPLITUDE TROUGH BEGINS TO PUSH INTO THE NW U.S.
FIRST WAVE OF ENERGY WILL KICK OUT AND PUSH A COLD FRONT INTO THE
CENTRAL PLAINS DURING THE DAYTIME ON WED. SHOULD BE ENTERING THE NW
PART OF THE CWA BY SUNRISE WED AND PUSH THROUGH DURING THE DAY. NAM
MORE PROGRESSIVE THAN THE GFS WITH THIS FRONT. ALL MODELS SHOWING
DECENT CAP OVER THE SE HALF OF THE CWA DURING THE AFTERNOON AND
BANKING ON THIS FEATURE TO KEEP THUNDERSTORMS AT BAY DURING THE DAY.
CHANCES INCREASE ESPECIALLY IN THE NORTHERN PART OF THE CWA WED
EVENING AND OVERNIGHT AS MID LEVEL WAVE ROTATES THROUGH HELPING COOL
OFF MID LEVEL TEMPS ESPECIALLY IN THE NORTH. GFS AND OLD EC MODELS
DO SHOW THE BETTER JET SUPPORT TO BE JUST A LITTLE NORTH OF US WITH
RIGHT ENTRANCE AND LEFT EXIT REGIONS OF COUPLED JET FAVORING NW NEB.
MODELS ALSO SHOWING BEST MID LEVEL FRONTOGENESIS IN THIS AREA. WILL
WAIT TO GET A LOOK AT THE 12Z EC RUN BUT UNLESS IT SHOWS SOMETHING
DIFFERENT WILL KEEP WITH PREVIOUS THINKING OF BEST CHANCES FOR
THUNDERSTORMS IN THE NORTHWEST CWA AND DRY IN OUR FAR SOUTHEAST AS
CAP EXPECTED TO HOLD AND EVEN STRENGTHEN IN THAT AREA OVERNIGHT. IN
REGARDS TO SEVERE POTENTIAL...DEEP LAYER SHEAR AND MU CAPE WOULD
SUPPORT SOME SEVERE IN THE AREA.
THURSDAY/THUR NIGHT NOT REAL CLEAR CUT AS MODELS DIFFERING ON PRECIP
CHANCES. INITIAL THOUGHT IS THAT WE WON`T SEE MUCH DURING THE DAY
AND THEN CHANCES INCREASE SOME OVERNIGHT AS LOW LEVEL INCREASES.
HOWEVER WILL LEAVE AT LEAST A SMALL CHANCE IN THE NORTH DURING THE
DAYTIME. AS FIRST WAVE EJECTS TO OUR NORTH...ANOTHER DEEPER MID
LEVEL LOW PRESSURE SYSTEM IS PROGGED TO DIG FROM THE PACIFIC NW ON
THURSDAY INTO SOUTHERN NEVADA BY SATURDAY BEFORE LIFTING NORTH INTO
SOUTHERN MANITOBA BY MONDAY NIGHT. THIS TRACK IS MAINLY BASED OFF
THE EC AND IF IT HOLDS TRUE...WE SHOULD BE DRY DURING THE DAYTIME ON
FRIDAY WITH SHORT WAVE RIDGING. STILL LINGERING CHANCES FOR RAIN
FRIDAY NIGHT INTO SATURDAY NIGHT WITH WARM FRONT LIFTING NORTH AND
CYCLONIC FLOW IN THE UPPER LEVELS. SUNDAY COULD BE INTERESTING AS
COLD FRONT SWEEPS THROUGH DURING THE AFTERNOON. EARLY LOOK AT CAPE
AND SHEAR WOULD POINT TO SEVERE WEATHER CHANCE BUT AS USUAL THAT
WILL DEPEND ON TIMING OF A SYSTEM WHICH IS STILL SEVERAL DAYS AWAY.
AS FAR AS HIGH TEMPERATURES GO...WE WILL SEE SOME VARIATION AS
FRONTAL BOUNDARIES PUSH THROUGH...WITH THINGS A LITTLE COOLER ON
WED IN THE NORTH CWA AND THEN OVER THE ENTIRE AREA THURS AND FRI
BEFORE IT WARMS UP AGAIN ON SAT INTO SUNDAY AHEAD OF NEXT COLD
FRONT. NEXT MONDAY SHOULD ONCE AGAIN BE A LITTLE COOLER BEHIND THE
FRONT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
1148 UPDATE...BRYANT
AVIATION/1021 UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...EWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
305 PM EDT TUE MAY 22 2012
.SYNOPSIS...
AN UPPER DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS TO THE
AREA THROUGH THURSDAY. A WARMING AND DRYING TREND WILL FOLLOW
FRIDAY THROUGH EARLY NEXT WEEK...AS AN UPPER RIDGE INTENSIFIES
OVER THE CAROLINAS.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 1245 PM TUESDAY...RADAR SHOWS SHOWERS DEVELOPING ACROSS THE
LOWER PEE DEE REGION WITH AN INCOMING VORTICITY LOBE...AND ALSO SOME
ACTIVITY ACROSS NORTHERN SECTIONS OF PENDER AND BLADEN COUNTIES.
VISIBLE SATELLITE (AND GLANCES OUT THE WINDOW) SHOW THE CUMULUS
FIELD IN AND AROUND WILMINGTON IS PRIMED FOR ACTIVITY AS WELL. THIS
REQUIRES ONLY SMALL CHANGES TO THE PREVIOUS FORECAST. DISCUSSION
FROM 1030 AM FOLLOWS...
TROPICAL DEPRESSION ALBERTO IS NO MORE. THE CONVECTION HAS BEEN
SHEARED OFF AND AWAY FROM THE LOW-LEVEL CIRCULATION MEANING THERE IS
NO LONGER A METHOD FOR ALBERTO TO EVACUATE AIR AND MAINTAIN LOWER
PRESSURES IN THE CENTER OF THE CIRCULATION. ALBERTO`S REMNANT
CIRCULATION IS CAUGHT UP IN THE SOUTHWEST FLOW AHEAD OF AN INCOMING
NEGATIVELY TILTED UPPER LEVEL TROUGH THAT WILL MOVE FROM THE
ALABAMA/GEORGIA BORDER THIS MORNING INTO SOUTH CAROLINA TONIGHT. THE
NEGATIVE TILT SHOULD BECOME SO EXTREME TONIGHT THE SYSTEM ACTUALLY
WILL CUT OFF INTO A CLOSED UPPER LOW WHICH SHOULD WOBBLE SLOWLY
OVERHEAD WEDNESDAY. FALLING MID-LEVEL TEMPERATURES AND A JUICY
SUBTROPICAL AIRMASS HERE AT THE SURFACE SPELL GROWING VERTICAL
INSTABILITY...WITH CAPE VALUES RISING TO AROUND 1500 J/KG THIS
AFTERNOON. WITH THE HELP OF MESOSCALE LIFT PROVIDED BY THE
SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD DEVELOP EARLY
THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY AREAS THAT MIGHT
BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES WHERE COOLER
ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY ENOUGH THIS
AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER PATTERN WELL
AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.
BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.
HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM TUESDAY...BOTH WED AND THU WILL BE IMPACTED BY A
COLD POOL ALOFT PASSING OVER THE FORECAST AREA...ALTHOUGH BY
THURSDAY THIS FEATURE WILL BE EXITING TO THE NORTH AND TEMPS
ALOFT WILL BEGIN WARMING...ESPECIALLY LATE IN THE DAY THURSDAY.
POTENTIALLY SHARP LAPSE RATES WEDNESDAY AFTERNOON INTO EVENING
WARRANTS MENTION OF HAIL AND GUSTY WINDS DESPITE ONLY "SEE TEXT"
WORDING AT THIS TIME FROM SPC. 500MB TEMPS SHOULD DIP TO -15 TO
-16 DEG CELSIUS OVERHEAD NEAR PEAK HEATING.
MENTIONABLE POP VALUES EXTEND INTO THURSDAY BUT WARMING ALOFT
MAY INHIBIT CONVECTION COMPARED TO WED. GREATER COVERAGE AND
TSTM INTENSITY REMAINS FAVORED WED AFTERNOON AS THE CORE OF THE
COOL POOL TRACK OVERHEAD.
MAX TEMPS SIMILAR WED AND THU...MAINLY MIDDLE AND UPPER 80S ACROSS
MOST INLAND LOCATIONS...AND LOWER 80S ALONG THE IMMEDIATE COAST.
PRIMARILY MIDDLE 60S FOR LOWS EACH MORNING GIVEN ONSHORE FLOW
AND PROJECTED DEWPOINTS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...FEW CHANGES TO THE LONG TERM FORECAST THIS
AFTERNOON WITH CONVECTION TAKING PRECEDENCE. MAIN THEME REMAINS
HOT HOWEVER AS MEDIUM RANGE GUIDANCE CONTINUES TO BUILD THE 500MB
RIDGE ACROSS THE SOUTHEAST FOR THE WEEKEND CONTINUING INTO MONDAY.
THE PATTERN DOES SHOW INDICATIONS OF BREAKING DOWN TUESDAY AS
CLOSED LOW IN THE WEST GETS KICKED OUT AND LOWERS HEIGHTS FROM
NORTH TO SOUTH.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 19Z...SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP
THIS AFTERNOON AHEAD OF AN APPROACHING COLD FRONT AND UPPER
IMPULSE. CONFIDENCE IN TIMING OF ACTIVITY INTO ANY TERMINAL IS
ONLY LOW TO MODERATE. ONE IMPULSE MOVING THROUGH THE FLO TERMINALS
ATTM SHOULD ENHANCE SEA BREEZE ACTIVITY FOR SEVERAL HOURS THIS
AFTERNOON FROM MYR TO ILM. WILL INDICATE SHOWERS/WITH TEMPO MVFR
AT ALL TERMINALS THIS AFTERNOON...WITH SHORT-TERM AMENDMENTS AS
RADAR COVERAGE INDICATES. VCTS WILL BE MOST LIKELY AT THE COASTAL
TERMINALS. SHORT PERIODS OF IFR ARE LIKELY WITH ANY THUNDERSTORMS
BUT THE DURATION SHOULD BE TOO SHORT TO MENTION IN AT LEAST THE
18Z TAFS. THIS CONVECTION SHOULD END BY LATE AFTERNOON...WITH A
SECOND ROUND OF CONVECTION DEVELOPING THIS EVENING PERSISTING
UNTIL MIDNIGHT OR EVEN AFTER AS THE UPPER IMPULSE ROTATES THROUGH.
THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY THIS OUT AFTER THE
PRECIPITATION ENDS AFTER MIDNIGHT...LEAVING THE WINDOW OPEN FOR BR
DEVELOPMENT. ATTM WILL INDICATE ONLY MVFR CONDITIONS AT FLO/LBT DUE
TO LIGHTER SURFACE WINDS AND LESS POTENTIAL CLOUD COVER. PATCHY
DENSE FOG COULD OCCUR ESPECIALLY IN SHELTERED AREAS WHERE SKIES
CLEAR OUT. ANY REDUCED FLIGHT CONDITIONS SHOULD IMPROVE RAPIDLY
AROUND SUNRISE WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE BY MID
MORNING.
EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...CURRENT OBSERVATIONS MATCH THE PREVIOUS
FORECAST CLOSELY...NO CHANGES ARE REQUIRED. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...
ALBERTO IS A DISSIPATING POST-TROPICAL DEPRESSION LOCATED ABOUT 250
MILES EAST-SOUTHEAST OF CAPE FEAR. WINDS ARE CURRENTLY SOUTH TO
SOUTHWEST ACROSS OUR COASTAL WATERS INDICATING THERE HAS BEEN NO
INFLUENCE FROM ALBERTO`S SMALL CIRCULATION. OUR WINDS ARE ACTUALLY
INFLUENCED BY THE CYCLONIC FLOW AROUND AN AREA OF LOW PRESSURE AND
COLD FRONT CURRENTLY ACROSS THE INLAND CAROLINAS. THIS SYSTEM IS NOT
EXPECTED TO REACH THE COAST... INSTEAD STALLING TONIGHT AND
DISSIPATING ON WEDNESDAY. UNTIL THEN... SOUTHWEST 10-15 KNOT WINDS
ARE EXPECTED...STRONGEST ALONG THE COAST THIS AFTERNOON AND FARTHER
AWAY FROM THE COAST TONIGHT. THUNDERSTORMS ARE EXPECTED TO DEVELOP
ALONG THE SEABREEZE FRONT THIS AFTERNOON. SOME OF THESE COULD BE ON
OR VERY NEAR THE BEACHES...SO MARINERS WILL WANT TO PAY CLOSE
ATTENTION TO THE SKY EARLY THIS AFTERNOON. THERE SHOULD BE A LULL IN
SHOWER/T-STORM ACTIVITY LATER THIS AFTERNOON INTO EARLY
EVENING...BUT NEW SHOWERS AND STORMS MAY DEVELOP OFFSHORE LATE THIS
EVENING AND OVERNIGHT.
SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...THE BIGGEST THREAT WED AND THU WILL BE
ISOLATED TO SCATTERED TSTMS THAT COULD TRACK ACROSS THE WATERS
INTACT. THIS WILL INTRODUCE CLOUD TO WATER LIGHTNING STRIKES AND
LOCALLY ROUGH CONDITIONS. OUTSIDE OF TSTMS...MAINLY SOUTHERLY
WINDS 15 KNOTS OR LESS WED AND THU...WITH A FEW HIGHER AFTERNOON
GUSTS ENHANCED BY THE SEA BREEZE CIRCULATION. 3-4 FOOT SEAS WED
AND THU COMPRISED OF SE WAVES 2-3 FEET IN 8-10 SECOND INTERVALS
AND S WAVES AROUND 2 FEET IN 5-6 SECOND WAVE INTERVALS.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 PM TUESDAY...NORTHEAST WINDS FOR THE FIRST COUPLE OF DAYS
VEERING TO THE EAST FOR LATE IN THE WEEKEND AS HIGH PRESSURE
RESIDES TO THE WEST AND LOW PRESSURE TO THE EAST. LOWER CONFIDENCE
IN SPEEDS AS THE LOWS TO THE EAST ARE WILD CARDS. OVERALL EXPECT
SPEEDS TO REMAIN BELOW FLAG CRITERIA HOWEVER. EXPECT SUMMER LIKE
SEAS OF 2-4 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MJC
LONG TERM...SHK
AVIATION...MRR/TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1242 PM EDT TUE MAY 22 2012
.SYNOPSIS...
A SOUTHWESTERLY FLOW OF LOW LEVEL MOISTURE WILL REMAIN IN PLACE OVER
THE NEXT FEW DAYS WHILE AN UPPER LEVEL DISTURBANCE TRIGGERS
THUNDERSTORMS THIS AFTERNOON THROUGH THURSDAY. AS THIS SYSTEM
EXITS...A WARMUP IS EXPECTED LATE IN THE WEEK AND THROUGH THE
HOLIDAY WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...RADAR SHOWS SHOWERS DEVELOPING ACROSS THE
LOWER PEE DEE REGION WITH AN INCOMING VORTICITY LOBE...AND ALSO SOME
ACTIVITY ACROSS NORTHERN SECTIONS OF PENDER AND BLADEN COUNTIES.
VISIBLE SATELLITE (AND GLANCES OUT THE WINDOW) SHOW THE CUMULUS
FIELD IN AND AROUND WILMINGTON IS PRIMED FOR ACTIVITY AS WELL. THIS
REQUIRES ONLY SMALL CHANGES TO THE PREVIOUS FORECAST. DISCUSSION
FROM 1030 AM FOLLOWS...
TROPICAL DEPRESSION ALBERTO IS NO MORE. THE CONVECTION HAS BEEN
SHEARED OFF AND AWAY FROM THE LOW-LEVEL CIRCULATION MEANING THERE IS
NO LONGER A METHOD FOR ALBERTO TO EVACUATE AIR AND MAINTAIN LOWER
PRESSURES IN THE CENTER OF THE CIRCULATION. ALBERTO`S REMNANT
CIRCULATION IS CAUGHT UP IN THE SOUTHWEST FLOW AHEAD OF AN INCOMING
NEGATIVELY TILTED UPPER LEVEL TROUGH THAT WILL MOVE FROM THE
ALABAMA/GEORGIA BORDER THIS MORNING INTO SOUTH CAROLINA TONIGHT. THE
NEGATIVE TILT SHOULD BECOME SO EXTREME TONIGHT THE SYSTEM ACTUALLY
WILL CUT OFF INTO A CLOSED UPPER LOW WHICH SHOULD WOBBLE SLOWLY
OVERHEAD WEDNESDAY. FALLING MID-LEVEL TEMPERATURES AND A JUICY
SUBTROPICAL AIRMASS HERE AT THE SURFACE SPELL GROWING VERTICAL
INSTABILITY...WITH CAPE VALUES RISING TO AROUND 1500 J/KG THIS
AFTERNOON. WITH THE HELP OF MESOSCALE LIFT PROVIDED BY THE
SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD DEVELOP EARLY
THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY AREAS THAT MIGHT
BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES WHERE COOLER
ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY ENOUGH THIS
AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER PATTERN WELL
AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.
BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.
HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM TUESDAY...COOL POCKET ALOFT ASSOCIATED WITH MID LEVEL
TROUGH MOVES ACROSS WEDNESDAY MORNING. THEREAFTER COMES WEAK HEIGHT
RISES AND WAA BUT A TRAILING VORT MAX SHOULD STILL MANAGE TO TOUCH
OFF SCATTERED AFTERNOON THUNDERSTORMS. FORECAST INSTABILITY AMPLE
ENOUGH TO DRAW ANOTHER SEE TEXT/5% FOR SEVERE FROM SPC...NOTING LACK
OF SHEAR TO SUPPORT ANY LEVEL OF ORGANIZATION IN CONVECTION.
TEMPERATURES WILL BE VERY CLOSE TO CLIMO. FORCING WILL BE ON THE
WANE FOR THE REMAINDER OF THE PERIOD WITH THE EXIT OF THE UPPER
TROUGH. YET ANOTHER VORT COMES THROUGH ON THE HEELS OF THE EXITING
TROUGH THURSDAY AFTERNOON. ITS A MUCH WEAKER FEATURE SO ONLY LOW
END CHANCE POPS APPEAR WARRANTED FOR WHAT SHOULD END UP BEING WIDELY
SCATTERED OR ISOLATED CONVECTIVE COVERAGE. THURSDAY HIGHS AND LOWS
WILL BE VERY CLOSE TO WEDNESDAYS AND THUS CLIMATOLOGY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...UPPER WAVE FROM THE SHORT TERM GOES ON TO
INTERACT WITH AMPLE MOISTURE STREAMING OUT OF THE CARIBBEAN AND
GUIDANCE SUGGESTS LOW PRESSURE GETS INDUCED IN THE BAHAMAS LATER IN
THE PERIOD. WRF SOLUTION APPEARS RATHER CLIMATOLOGICALLY EXTREME AT
THIS POINT BUT GIVEN THAT SSTS WERE WARM ENOUGH TO ALREADY SUPPORT
ALBERTO TOUGH TO RULE OUT. FOR NOW THE SHALLOWER SYSTEM DEPICTED BY
THE GFS SEEMS MORE APPEALING AND THERE WILL BE NO IMPACT LOCALLY ON
FRIDAY AS UPPER RIDGE BUILDS OVER GULF STATES. JUST ISOLATED
CONVECTION AS NORTHERLY FLOW LOCALLY WILL CONTAIN SOME WEAK SHORT
WAVE IMPULSES AND A HEALTHY SEA BREEZE CIRCULATION WILL DEVELOP. NOT
MUCH CHANGES INTO THE HOLIDAY WEEKEND AND WITH THE AFOREMENTIONED
POSSIBLE LOW OUT OF THE PICTURE THE UPPER RIDGE WILL BE THE DOMINANT
PLAYER. TEMPERATURES WILL RISE ABOVE CLIMATOLOGY. SURFACE FLOW WILL
BE A BIT MORE EASTERLY THAN MOST LATE SPRING WARM UPS TEMPERING THE
WARMTH SLIGHTLY AND PUSHING THE SEA BREEZE WELL INLAND. ISOLATED
CONVECTION EACH AFTERNOON MAY BE SHUNTED ALL THE WAY TO WESTERN
ZONES.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS
AFTERNOON AHEAD OF AN APPROACHING COLD FRONT AND UPPER IMPULSE.
CONFIDENCE IN TIMING OF ACTIVITY INTO ANY TERMINAL IS ONLY LOW TO
MODERATE. ONE IMPULSE MOVING THROUGH THE FLO TERMINALS ATTM SHOULD
ENHANCE SEA BREEZE ACTIVITY FOR SEVERAL HOURS THIS AFTERNOON FROM
MYR TO ILM. WILL INDICATE SHOWERS/WITH TEMPO MVFR AT ALL TERMINALS
THIS AFTERNOON...WITH SHORT-TERM AMENDMENTS AS RADAR COVERAGE
INDICATES. VCTS WILL BE MOST LIKELY AT THE COASTAL TERMINALS. SHORT
PERIODS OF IFR ARE LIKELY WITH ANY THUNDERSTORMS BUT THE DURATION
SHOULD BE TOO SHORT TO MENTION IN AT LEAST THE 18Z TAFS. THIS
CONVECTION SHOULD END BY LATE AFTERNOON...WITH A SECOND ROUND OF
CONVECTION DEVELOPING THIS EVENING PERSISTING UNTIL MIDNIGHT OR
EVEN AFTER AS THE UPPER IMPULSE ROTATES THROUGH.
THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY THIS OUT AFTER THE
PRECIPITATION ENDS AFTER MIDNIGHT...LEAVING THE WINDOW OPEN FOR BR
DEVELOPMENT. ATTM WILL INDICATE ONLY MVFR CONDITIONS AT FLO/LBT DUE
TO LIGHTER SURFACE WINDS AND LESS POTENTIAL CLOUD COVER. PATCHY
DENSE FOG COULD OCCUR ESPECIALLY IN SHELTERED AREAS WHERE SKIES
CLEAR OUT. ANY REDUCED FLIGHT CONDITIONS SHOULD IMPROVE RAPIDLY
AROUND SUNRISE WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE BY MID
MORNING.
EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...CURRENT OBSERVATIONS MATCH THE PREVIOUS
FORECAST CLOSELY...NO CHANGES ARE REQUIRED. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...
ALBERTO IS A DISSIPATING POST-TROPICAL DEPRESSION LOCATED ABOUT 250
MILES EAST-SOUTHEAST OF CAPE FEAR. WINDS ARE CURRENTLY SOUTH TO
SOUTHWEST ACROSS OUR COASTAL WATERS INDICATING THERE HAS BEEN NO
INFLUENCE FROM ALBERTO`S SMALL CIRCULATION. OUR WINDS ARE ACTUALLY
INFLUENCED BY THE CYCLONIC FLOW AROUND AN AREA OF LOW PRESSURE AND
COLD FRONT CURRENTLY ACROSS THE INLAND CAROLINAS. THIS SYSTEM IS NOT
EXPECTED TO REACH THE COAST... INSTEAD STALLING TONIGHT AND
DISSIPATING ON WEDNESDAY. UNTIL THEN... SOUTHWEST 10-15 KNOT WINDS
ARE EXPECTED...STRONGEST ALONG THE COAST THIS AFTERNOON AND FARTHER
AWAY FROM THE COAST TONIGHT. THUNDERSTORMS ARE EXPECTED TO DEVELOP
ALONG THE SEABREEZE FRONT THIS AFTERNOON. SOME OF THESE COULD BE ON
OR VERY NEAR THE BEACHES...SO MARINERS WILL WANT TO PAY CLOSE
ATTENTION TO THE SKY EARLY THIS AFTERNOON. THERE SHOULD BE A LULL IN
SHOWER/T-STORM ACTIVITY LATER THIS AFTERNOON INTO EARLY
EVENING...BUT NEW SHOWERS AND STORMS MAY DEVELOP OFFSHORE LATE THIS
EVENING AND OVERNIGHT.
SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...BROAD AND WEAK HIGH PRESSURE ACROSS THE WESTERN
ATLANTIC IN TANDEM WITH PIEDMONT TROUGHINESS TO BRING SSW FLOW ON
WEDNESDAY. A DOMINANT 3 TO 4 FT SEA STATE WILL BE A COMBO OF SW WIND
CHOP AND E SWELL...BOTH COMPONENTS BEING COMPARABLE IN RELATIVE
STRENGTH. CONDITIONS WILL NOT CHANCE TOO MUCH INTO THURSDAY BUT
THEIR IS SOME UNCERTAINTY. LOW PRESSURE WILL MOVE OUT OF THE
CARIBBEAN AND INTO THE BAHAMAS LATE IN THE PERIOD. THERE IS QUITE A
DIFFERENCE IN GUIDANCE WITH RESPECT TO THIS SYSTEMS EVENTUAL FATE.
FOR THIS PERIOD ITS PRESENCE MAY CUT DOWN ON THE SWELL ENERGY BY
INTERRUPTING THE LONG EASTERLY FETCH.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...FOR THE MOST PART A LARGE AREA OF HIGH PRESSURE
ACROSS THE WESTERN ATLANTIC WILL BE RESPONSIBLE FOR THE LOCAL SET OF
WIND AND WAVES. THERE IS A COMPLICATING FACTOR THAT FRIDAY MAY SEE
SOME KIND OF WEAK LOW OF TROPICAL ORIGINS MOVING PARALLEL TO THE
COAST...AND LIKELY WELL OFFSHORE. THERE ARE SOME MODEL SOLUTIONS
THAT HAVE IT CLOSER AND STRONGER AND THEREFORE MUCH OF A FACTOR IN
THE FORECAST. FOR NOW FOLLOWING WEAKER SOLUTIONS THAT SHOW A WEAK
LOW OR OPEN TROUGH IN THE OTHERWISE EASTERLY FLOW BORNE OF
AFOREMENTIONED HIGH. SEAS IN THE 2 TO 4 FT RANGE AS ALTHOUGH WINDS
WILL REMAIN LIGHT THE EASTERLY FETCH LENGTH COULD BE QUITE LONG AND
ALLOW FOR A SIGNIFICANT SWELL COMPONENT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1047 AM EDT TUE MAY 22 2012
.SYNOPSIS...
A SOUTHWESTERLY FLOW OF LOW LEVEL MOISTURE WILL REMAIN IN PLACE OVER
THE NEXT FEW DAYS WHILE AN UPPER LEVEL DISTURBANCE TRIGGERS
THUNDERSTORMS THIS AFTERNOON THROUGH THURSDAY. AS THIS SYSTEM
EXITS...A WARMUP IS EXPECTED LATE IN THE WEEK AND THROUGH THE
HOLIDAY WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...TROPICAL DEPRESSION ALBERTO IS NO MORE. THE
CONVECTION HAS BEEN SHEARED OFF AND AWAY FROM THE LOW-LEVEL
CIRCULATION MEANING THERE IS NO LONGER A METHOD FOR ALBERTO TO
EVACUATE AIR AND MAINTAIN LOWER PRESSURES IN THE CENTER OF THE
CIRCULATION. ALBERTO`S REMNANT CIRCULATION IS CAUGHT UP IN THE
SOUTHWEST FLOW AHEAD OF AN INCOMING NEGATIVELY TILTED UPPER LEVEL
TROUGH THAT WILL MOVE FROM THE ALABAMA/GEORGIA BORDER THIS MORNING
INTO SOUTH CAROLINA TONIGHT. THE NEGATIVE TILT SHOULD BECOME SO
EXTREME TONIGHT THE SYSTEM ACTUALLY WILL CUT OFF INTO A CLOSED UPPER
LOW WHICH SHOULD WOBBLE SLOWLY OVERHEAD WEDNESDAY. FALLING MID-LEVEL
TEMPERATURES AND A JUICY SUBTROPICAL AIRMASS HERE AT THE SURFACE
SPELL GROWING VERTICAL INSTABILITY...WITH CAPE VALUES RISING TO
AROUND 1500 J/KG THIS AFTERNOON. WITH THE HELP OF MESOSCALE LIFT
PROVIDED BY THE SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD
DEVELOP EARLY THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY
AREAS THAT MIGHT BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES
WHERE COOLER ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY
ENOUGH THIS AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER
PATTERN WELL AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.
BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.
HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM TUESDAY...COOL POCKET ALOFT ASSOCIATED WITH MID LEVEL
TROUGH MOVES ACROSS WEDNESDAY MORNING. THEREAFTER COMES WEAK HEIGHT
RISES AND WAA BUT A TRAILING VORT MAX SHOULD STILL MANAGE TO TOUCH
OFF SCATTERED AFTERNOON THUNDERSTORMS. FORECAST INSTABILITY AMPLE
ENOUGH TO DRAW ANOTHER SEE TEXT/5% FOR SEVERE FROM SPC...NOTING LACK
OF SHEAR TO SUPPORT ANY LEVEL OF ORGANIZATION IN CONVECTION.
TEMPERATURES WILL BE VERY CLOSE TO CLIMO. FORCING WILL BE ON THE
WANE FOR THE REMAINDER OF THE PERIOD WITH THE EXIT OF THE UPPER
TROUGH. YET ANOTHER VORT COMES THROUGH ON THE HEELS OF THE EXITING
TROUGH THURSDAY AFTERNOON. ITS A MUCH WEAKER FEATURE SO ONLY LOW
END CHANCE POPS APPEAR WARRANTED FOR WHAT SHOULD END UP BEING WIDELY
SCATTERED OR ISOLATED CONVECTIVE COVERAGE. THURSDAY HIGHS AND LOWS
WILL BE VERY CLOSE TO WEDNESDAYS AND THUS CLIMATOLOGY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...UPPER WAVE FROM THE SHORT TERM GOES ON TO
INTERACT WITH AMPLE MOISTURE STREAMING OUT OF THE CARIBBEAN AND
GUIDANCE SUGGESTS LOW PRESSURE GETS INDUCED IN THE BAHAMAS LATER IN
THE PERIOD. WRF SOLUTION APPEARS RATHER CLIMATOLOGICALLY EXTREME AT
THIS POINT BUT GIVEN THAT SSTS WERE WARM ENOUGH TO ALREADY SUPPORT
ALBERTO TOUGH TO RULE OUT. FOR NOW THE SHALLOWER SYSTEM DEPICTED BY
THE GFS SEEMS MORE APPEALING AND THERE WILL BE NO IMPACT LOCALLY ON
FRIDAY AS UPPER RIDGE BUILDS OVER GULF STATES. JUST ISOLATED
CONVECTION AS NORTHERLY FLOW LOCALLY WILL CONTAIN SOME WEAK SHORT
WAVE IMPULSES AND A HEALTHY SEA BREEZE CIRCULATION WILL DEVELOP. NOT
MUCH CHANGES INTO THE HOLIDAY WEEKEND AND WITH THE AFOREMENTIONED
POSSIBLE LOW OUT OF THE PICTURE THE UPPER RIDGE WILL BE THE DOMINANT
PLAYER. TEMPERATURES WILL RISE ABOVE CLIMATOLOGY. SURFACE FLOW WILL
BE A BIT MORE EASTERLY THAN MOST LATE SPRING WARM UPS TEMPERING THE
WARMTH SLIGHTLY AND PUSHING THE SEA BREEZE WELL INLAND. ISOLATED
CONVECTION EACH AFTERNOON MAY BE SHUNTED ALL THE WAY TO WESTERN
ZONES.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...CONFIDENCE IS HIGH THAT LIGHT FOG WILL IMPROVE QUICKLY
AS INDICATED IN TAFS. VFR IS THEN EXPECTED THE REMAINDER OF THE
MORNING EXCEPT FOR TEMPO MVFR CEILINGS AT THE COASTAL TERMINALS AS
THE SEA BREEZE DEVELOPS...AND TEMPO CONDITIONS IN SHOWERS AT FLO/LBT
BY LATE MORNING.
A COLD FRONT WILL APPROACH FROM THE WEST TODAY BUT IT IS NOT EXPECTED
TO MOVE THROUGH THE TERMINALS. AHEAD OF THE FRONT THERE IS MODERATE
TO HIGH CONFIDENCE SHOWERS AND THUNDERSTORMS WILL DEVELOP. CONVECTION
WILL AFFECT THE FLO/LBT TERMINALS AS EARLY AS 15-17Z AND THE COASTAL
TERMINALS BY 17-19Z. ATTM WILL INDICATE SHOWERS WITH TEMPO MVFR AND
VCTS...ALTHOUGH VCTS MAY BE MORE LIKELY AT THE COASTAL TERMINALS THAN
AT FLO/LBT. SHORT PERIODS OF IFR ARE LIKELY WITH THE THUNDERSTORMS
BUT THE DURATION SHOULD BE TOO SHORT TO MENTION IN TAFS. A SECOND
ROUND OF ACTIVITY IS POSSIBLE LATE THIS AFTERNOON AT FLO/LBT AND THIS
EVENING AT THE COASTAL TERMINALS AS THE UPPER IMPULSE ROTATES
THROUGH.
THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY SCATTER OUT OVERNIGHT
LEAVING THE WINDOW OPEN FOR BR DEVELOPMENT. ATTM WILL INDICATE ONLY
MVFR CONDITIONS AT FLO/LBT DUE TO LIGHTER SURFACE WINDS AND LESS
POTENTIAL CLOUD COVER. PATCHY DENSE FOG COULD OCCUR ESPECIALLY IN
SHELTERED AREAS WHERE SKIES CLEAR OUT.
EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...ALBERTO IS A DISSIPATING POST-TROPICAL
DEPRESSION LOCATED ABOUT 250 MILES EAST-SOUTHEAST OF CAPE FEAR.
WINDS ARE CURRENTLY SOUTH TO SOUTHWEST ACROSS OUR COASTAL WATERS
INDICATING THERE HAS BEEN NO INFLUENCE FROM ALBERTO`S SMALL
CIRCULATION. OUR WINDS ARE ACTUALLY INFLUENCED BY THE CYCLONIC FLOW
AROUND AN AREA OF LOW PRESSURE AND COLD FRONT CURRENTLY ACROSS THE
INLAND CAROLINAS. THIS SYSTEM IS NOT EXPECTED TO REACH THE COAST...
INSTEAD STALLING TONIGHT AND DISSIPATING ON WEDNESDAY. UNTIL THEN...
SOUTHWEST 10-15 KNOT WINDS ARE EXPECTED...STRONGEST ALONG THE COAST
THIS AFTERNOON AND FARTHER AWAY FROM THE COAST TONIGHT.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE SEABREEZE FRONT THIS
AFTERNOON. SOME OF THESE COULD BE ON OR VERY NEAR THE BEACHES...SO
MARINERS WILL WANT TO PAY CLOSE ATTENTION TO THE SKY EARLY THIS
AFTERNOON. THERE SHOULD BE A LULL IN SHOWER/T-STORM ACTIVITY LATER
THIS AFTERNOON INTO EARLY EVENING...BUT NEW SHOWERS AND STORMS MAY
DEVELOP OFFSHORE LATE THIS EVENING AND OVERNIGHT.
SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...BROAD AND WEAK HIGH PRESSURE ACROSS THE WESTERN
ATLANTIC IN TANDEM WITH PIEDMONT TROUGHINESS TO BRING SSW FLOW ON
WEDNESDAY. A DOMINANT 3 TO 4 FT SEA STATE WILL BE A COMBO OF SW WIND
CHOP AND E SWELL...BOTH COMPONENTS BEING COMPARABLE IN RELATIVE
STRENGTH. CONDITIONS WILL NOT CHANCE TOO MUCH INTO THURSDAY BUT
THEIR IS SOME UNCERTAINTY. LOW PRESSURE WILL MOVE OUT OF THE
CARIBBEAN AND INTO THE BAHAMAS LATE IN THE PERIOD. THERE IS QUITE A
DIFFERENCE IN GUIDANCE WITH RESPECT TO THIS SYSTEMS EVENTUAL FATE.
FOR THIS PERIOD ITS PRESENCE MAY CUT DOWN ON THE SWELL ENERGY BY
INTERRUPTING THE LONG EASTERLY FETCH.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...FOR THE MOST PART A LARGE AREA OF HIGH PRESSURE
ACROSS THE WESTERN ATLANTIC WILL BE RESPONSIBLE FOR THE LOCAL SET OF
WIND AND WAVES. THERE IS A COMPLICATING FACTOR THAT FRIDAY MAY SEE
SOME KIND OF WEAK LOW OF TROPICAL ORIGINS MOVING PARALLEL TO THE
COAST...AND LIKELY WELL OFFSHORE. THERE ARE SOME MODEL SOLUTIONS
THAT HAVE IT CLOSER AND STRONGER AND THEREFORE MUCH OF A FACTOR IN
THE FORECAST. FOR NOW FOLLOWING WEAKER SOLUTIONS THAT SHOW A WEAK
LOW OR OPEN TROUGH IN THE OTHERWISE EASTERLY FLOW BORNE OF
AFOREMENTIONED HIGH. SEAS IN THE 2 TO 4 FT RANGE AS ALTHOUGH WINDS
WILL REMAIN LIGHT THE EASTERLY FETCH LENGTH COULD BE QUITE LONG AND
ALLOW FOR A SIGNIFICANT SWELL COMPONENT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
139 AM EDT TUE MAY 22 2012
.SYNOPSIS...
ALBERTO WILL ACCELERATE OUT TO THE NORTHEAST THROUGH TUESDAY...
MOVING FARTHER AWAY FROM THE U.S. MAINLAND. A WEAK COLD FRONT WILL
SNAKE TO THE EAST AND STALL NEAR OR WEST OF THE FORECAST AREA
TUESDAY NIGHT AND SLOWLY DISSIPATE WEDNESDAY OR THURSDAY. HIGH
PRESSURE WILL EVOLVE ACROSS THE WESTERN ATLANTIC LATE IN THE WEEK
AND RIDGE ACROSS THE REGION THROUGH THE WEEKEND...BRINGING SUMMER
LIKE CONDITIONS.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 1010 PM MONDAY...THE DIURNALLY DRIVEN ISOLATED CONVECTION THIS
EVENING IS NEARLY OVERWITH...AND SHOULD BE A MEMORY BY LATE THIS
EVENING AS THE SEA BREEZE BOUNDARY HAVING TRACKED WELL INLAND...
LOSES ITS LIFTING CAPABILITIES. THIS WILL LEAVE A MOSTLY CLEAR SKY
FOR THE OVERNIGHT...WITH SOME INCREASE OF MOISTURE WEST OF THE I-95
CORRIDOR TOWARDS TUESDAY DAYBREAK. HAVE KEPT POPS NULL AND VOID FROM
LATE THIS EVENING UNTIL THE START OF THE SHORT TERM WHEN LIFT AHEAD
OF THE COLD FRONT BECOMES APPARENT. AS FOR MIN TEMPS...SLIGHT
ADJUSTMENTS MAY BE NEEDED UPWARD TO ACCOUNT FOR THE WIDESPREAD LOW
TO MID 60S DEWPOINTS OVERNIGHT. PATCHY TO AREAS OF FOG WILL BE
POSSIBLE GIVEN THE DECENT RAD CONDITIONS...DECOUPLING OF THE
WINDS...AND AVAILABLE LOW LEVEL MOISTURE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...UNSETTLED WEATHER THROUGH THE PERIOD AS AN UPPER
TROUGH DROPS IN FROM THE NORTHWEST TUE THEN BECOMES SEMI-CUTOFF OVER
THE AREA WED. LOOKS LIKE BOTH TUE AND WED WILL BE ACTIVE AS FAR AS
CONVECTION IS CONCERNED. HIGH WILL BE SIMILAR BOTH DAYS...LOW TO MID
80S...WITH DEWPOINT IN THE LOW TO MID 60S. UPPER TROUGH/LOW AND
ASSOCIATED COLD AIR ALOFT COMBINED WITH DIURNAL HEATING...60 DEGREE
DEWPOINTS...CONVERGENCE ALONG THE SEABREEZE WILL PRODUCE CONVECTION
EACH DAY. COVERAGE WISE WED HAD LOOKED A LITTLE MORE FAVORABLE BUT
LATEST GUIDANCE HAS BACKED OFF A BIT ON THE DEEPER MOISTURE. NOW
BOTH DAYS APPEAR SIMILAR WITH RESPECT TO BOTH PRECIP COVERAGE AND
INTENSITY...CARRYING 40-50 POP BOTH DAYS. SBCAPE VALUES ARE IN THE
1000-1500 J/KG RANGE WITH VERTICAL PROFILES SUGGESTING A FEW STRONG
TO POTENTIALLY SEVERE PULSE STORMS COULD DEVELOP. SPC MAINTAINS THE
SEE TEXT FOR TUE AND WITH A SIMILAR ENVIRONMENT EXPECTED ON WED
WOULD NOT BE SHOCKED IF A SEE TEXT WERE ISSUED FOR WED AT SOME
POINT...ESPECIALLY WITH THE COLDEST CORE ALOFT DIRECTLY
OVERHEAD...THOUGH IT WILL BE MODIFYING. PREVIOUS FORECAST CARRIED
CHANCE POP FOR TUE NIGHT...AND GIVEN THE UPPER TROUGH/LOW OVERHEAD
WOULD EXPECT CONVECTION TO CONTINUE INTO THE EARLY MORNING HOURS.
WED NIGHT THINGS START TO DRY OUT AS THE UPPER LOW LIFTS NORTH AND
DRIER AIR STARTS TO INFILTRATE FROM THE SOUTHWEST. OVERNIGHT LOWS
WILL RUN IN THE LOW TO MID 60S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...THE SOUTHERLY RETURN FLOW INITIALLY AROUND
BERMUDA HIGH WILL BE REPLACED BY A NORTHEAST FLOW AS HIGH PRESSURE
RIDGES DOWN FROM CANADA BY SAT. OVERALL THE SURFACE FLOW WILL BE
DOMINATED MORE BY LAND/SEA BREEZE THROUGH MOST OF THE LONG TERM AS
PRESSURE PATTERN REMAINS WEAK. EXPECT DEEP S-SW FLOW RETURN FLOW ON
THURS AS MID TO UPPER TROUGH CONTINUES TO DIG DOWN TO OUR WEST AND
BERMUDA HIGH RIDGES IN FROM THE ATLANTIC. THE H5 TROUGH AXIS SHOULD
MOVE OFF SHORE THURS NIGHT WITH A DEEPER NE FLOW DEVELOPING AS UPPER
RIDGE BUILDS INTO THE CAROLINAS FROM THE WEST THROUGH THE WEEKEND.
ENERGY FROM THIS H5 SHORTWAVE MAY PROVIDE SOME ENHANCEMENT TO
LOCALIZED CONVECTION THURS AFTERNOON BUT WE WILL ACTUALLY GET SOME
DRIER AIR MOVING IN FROM THE SW IN THE MID LEVELS COMING AROUND THE
BASE OF THE TROUGH ON THURS. THIS SHOULD HELP TO INHIBIT ANY STRONG
CONVECTION BUT WILL KEEP ISOLATED SHWRS IN THE FORECAST MAINLY LATE
DAY THURS INTO THURS NIGHT BEFORE SHORTWAVE LIFTS OFF TO THE
NORTHEAST. EXPECT PLENTY OF SUBSIDENCE ON BACK END OF TROUGH AS
RIDGE BUILDS IN LATE FRI THROUGH THE WEEKEND. HEIGHTS INCREASE CLOSE
TO 590 DEM OVER THE WEEKEND AS RIDGE BUILDS TO OUR WEST. OVERALL
EXPECT ONLY LOCALIZED CONVECTION POSSIBLE ALONG SEA BREEZE WITH A
SUMMER-LIKE AIR MASS IN PLACE. DEWPOINTS WILL BE IN THE MID 60S
THROUGH THE WEEKEND. A WAVE OF LOW PRESSURE MAY MOVE INTO THE
CAROLINAS SUN NIGHT INTO MONDAY WHICH MAY PRODUCE A BETTER CHC OF
PCP TOWARD THE END OF THE MEMORIAL DAY WEEKEND WITH A STRONGER ON
SHORE FLOW.
TEMPS SHOULD RUN ABOVE NORMAL THROUGH THE EXTENDED PERIOD AS RIDGE
BUILDS AND HEIGHTS RISE. EXPECT LESS OF A DIURNAL TREND AS A MORE
HUMID AIR MASS WILL REMAIN IN PLACE. OVERALL 80S DURING THE DAY AND
60S AT NIGHT. TEMPS SHOULD BE HIGHEST ON SUNDAY AS HEIGHTS PEAK OVER
LOCAL AREA NEAR 590 DEM.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...EXPECT VFR THROUGH THE EARLY OVERNIGHT HOURS...WITH
PATCHY DENSE FOG CREATING MVFR/POTENTIAL IFR LATE OVERNIGHT INTO THE
EARLY MORNING HOURS. VFR WILL PREVAIL BY MORNING...WITH POTENTIAL
FOR BRIEF MVFR IN AFTERNOON VCSH.
FEW/SCT MID TO HIGH LEVEL CLOUDS WILL LINGER THROUGH THE OVERNIGHT
HOURS...WITH LIGHT AND VARIABLE WINDS. GIVEN AVAILABLE LOW LEVEL
MOISTURE...LIGHT WINDS AND SOMEWHAT MODERATE RADIATIONAL COOLING
CONDITIONS...EXPECT PATCHY DENSE FOG LATE OVERNIGHT INTO THE EARLY
MORNING HOURS. FOR NOW HAVE KEPT RESTRICTIONS AT MVFR...BUT CANNOT
RULE OUT VISIBILITIES BEING REDUCED EVEN MORE CREATING IFR
CONDITIONS...ESPECIALLY ALONG THE COAST. AFTER DAYBREAK...ANY
LINGERING FOG WILL QUICKLY BURN OFF AND POSSIBLY WILL SEE SCT
LOWERED CLOUD HEIGHTS. VFR WILL PREVAIL WITH LIGHT WEST WINDS WHICH
WILL GRADUALLY BACK TO THE SOUTH-SOUTHWEST. BY THE AFTERNOON
HOURS...SUSTAINED WINDS WILL BE AOB 12 KTS. FOR LATE MORNING THROUGH
THE END OF THE VALID PERIOD...WILL HAVE CHANCE FOR ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. FOR NOW HAVE KEPT IN VCSH.
CANNOT RULE OUT BRIEF MVFR IN HEAVIER DOWNPOURS. AFTER
SUNSET...WINDS WILL BECOME LIGHT WITH BKN CLOUD COVER.
EXTENDED OUTLOOK...SCATTERED SHOWERS CREATING MVFR...WITH ISOLATED
THUNDERSTORMS CREATING TEMPO IFR POSSIBLE THROUGH THE EXTENDED
PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 PM MONDAY...ALBERTO IS ON THE MOVE...BUT FORTUNATELY
TOWARD THE EAST NORTHEAST TAKING IT WELL OFFSHORE FROM THE SOUTHEAST
U.S. COAST TONIGHT THROUGH TUESDAY. THE LATEST HRRR HAS FINALLY
CAUGHT UP WITH THE GENERAL CONSENSUS OF PUSHING IT FURTHER AWAY FROM
THE MAINLAND. LOOK FOR VEERING WIND DIRECTIONS OVERNIGHT FROM NE-E
TO W-NW BY DAYBREAK TUESDAY. WIND SPEEDS...5 TO 10 KT.
SIGNIFICANT SEAS WILL RUN AROUND 3 FT THIS EVENING. WAVEWATCH3 AND
SWAN INDICATE AN ESE 4 TO 5 FT WAVE TRAIN WITH PERIODS 9-10 SECONDS
WILL AFFECT THE ILM WATERS DURING THE PRE-DAWN HOURS OF TUESDAY AND
THERE-AFTER. WILL INDICATE CURRENT SIGNIFICANT SEAS OF 2 TO 3 FT...
BUILDING TO 3 TO 4 FT OVERNIGHT INTO TUESDAY. THE OUTER WATERS FROM
CAPE FEAR NORTHWARD COULD OBSERVE 5 FOOTERS FROM THIS TRAIN.
THE SHADOW CREATED BY FPS WITH AN EASTERLY SWELL...WILL KEEP SEAS
CLOSER TO 2 FT ACROSS THE WATERS OFF BRUNSWICK COUNTY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 2 PM MONDAY...SOUTH TO SOUTHWEST FLOW WILL DOMINATE THE
PERIOD. SWELL FROM ALBERTO WILL AFFECT THE WATERS TUE INTO WED.
WIND SPEEDS WILL BE 10 TO 15 KT FOR THE MAJORITY OF THE PERIOD...
SLIGHTLY LESS AT NIGHT...WITH SOME NEAR SHORE ENHANCEMENT EACH DAY
AS THE SEABREEZE DEVELOPS. SEAS WILL BE A COMBINATION OF SOUTHERLY
WIND WAVE AND SOUTHEAST TO EAST ALBERTO SWELL...RUNNING 3 TO 4 FT
BOTH TUE AND WED.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...SOUTHERLY RETURN FLOW ON THURS AROUND BERMUDA
HIGH WILL BE REPLACED BY A N-NE FLOW THROUGH LATE FRI AS HIGH
PRESSURE BUILDS DOWN FROM CANADA. WINDS NEAR SHORE WILL BE DRIVEN
BY LAND/SEA BREEZE AS OVERALL PRESSURE PATTERN REMAINS MORE ON THE
WEAK SIDE. WINDS GENERALLY LESS THAN 15 KTS THURS AND FRI MAY
INCREASE THROUGH THE LATTER HALF OF THE WEEKEND AS A WAVE OF LOW
PRESSURE MOVES WESTWARD FROM THE OFF SHORE ATLANTIC WATERS TOWARD
THE LOCAL WATERS.
SEAS WILL BE REMAIN 2 TO 3 FT THROUGH MOST OF THE PERIOD BUT MAY
INCREASE WITH A STRONG ON SHORE PUSH BY LATE IN THE WEEKEND AS WAVE
OF LOW PRESSURE MIGRATES WESTWARD TOWARD LOCAL WATERS. SEAS WILL MIX
WITH A DECREASING EASTERLY SWELL AROUND 9 SECONDS ON THURS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...III
LONG TERM...RGZ
AVIATION...SGL/RJD
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1241 AM EDT TUE MAY 22 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE OUT OF THE AREA THIS EVENING. HIGH
PRESSURE WILL GRADUALLY BUILD EAST OVER THE REGION BY WEDNESDAY
MORNING. THE HIGH PRESSURE CENTER WILL MOVE TO THE EAST COAST BY
WEDNESDAY NIGHT ALLOWING A WARM FRONT TO LIFT NORTH ACROSS THE
AREA THURSDAY. A WEAK COLD FRONT WILL APPROACH THE AREA LATE FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
EXCEPT FOR A CLUSTER OF CONVECTION CENTERED IN WAYNE CO...MUCH OF
THE DAYTIME CONVECTION HAD DISSIPATED. A BAND OF SHRA IN THE COOLER
AIR OVER THE WESTERN PART OF THE AREA ASSOCIATED WITH THE UPPER
TROUGH IS TRYING TO GET GOING BUT WILL HAVE A HARD TIME DUE TO A
MORE STABLE AIRMASS IN THAT AREA. WILL KEEP SMALL CHANCE GOING FOR
MOST AREAS THROUGH MIDNIGHT THEN BEGIN TO SHIFT CHANCE INTO THE
SOUTHEAST HALF OF THE AREA OVER THE COURSE OF THE REST OF THE NIGHT.
RUC AND HRRR DISAGREE SO OVERALL CONFIDENCE LOW FOR THE REST OF THE
NIGHT BUT DO FEEL ANY NEW ACTIVITY WILL BE LIGHT.
REST OF FORECAST SEEMS TO BE ON TRACK SO LITTLE WILL BE CHANGED.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
THE FRONT WILL
BE JUST TO THE EAST OF THE FORECAST AREA. WITH A FAIR AMOUNT OF
MOISTURE...WILL CONTINUE WITH CHANCE POPS INTO THE
AFTERNOON...MAINLY IN THE EAST...WITH DECREASING CLOUDS ELSEWHERE.
OTHERWISE HIGH PRESSURE BUILDING IN TUESDAY NIGHT AND THE HIGH WILL
WEAKEN WEDNESDAY NIGHT. A WARM FRONT WILL MOVE ACROSS THE AREA
THURSDAY. ON THE EDGE ABOUT THE THREAT OF PRECIPITATION...ANY QPF
WOULD BE VERY LIGHT. JUST WENT WITH 20 POPS AT THE MOMENT AND WILL
MONITOR IT CLOSELY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
BEGINNING FRIDAY IN THE LONG TERM GFS AND ECMWF SHOWING COLD FRONT
APPROACHING THE AREA BUT LOOKS LIKE TEMPS WILL BE QUITE ABOVE NORMAL
WITH SHOWERS AND THUNDERSTORMS HOLDING OFF MOVING INTO WESTERN AREAS
UNTIL LATE DAY/EVENING...WITH BETTER CHANCES ACROSS THE NORTHERN
HALF OF THE AREA FRIDAY NIGHT. THE PATTERN LOOKS TO BE TRICKY GOING
INTO THE WEEKEND HOWEVER WITH BOTH MODELS SHOWING THE FRONTAL
BOUNDARY ORIENTING ITSELF MORE WEST TO EAST ACROSS THE AREA ON
SATURDAY. WITH THE BOUNDARY ACROSS THE AREA THE CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE. HOWEVER...GIVEN THIS FAR OUT IN THE
EXTENDED MAINLY WENT WITH LOW CHC TO SLGT CHC POPS ON SATURDAY.
THERE IS SOME DISCREPANCY WITH HOW STRONG HIGH PRESSURE TO THE NORTH
MAY RIDGE INTO THE AREA ON SUNDAY PUSHING THE FRONT FURTHER SOUTH
AWAY FROM THE AREA...BUT FOR NOW LEANED TOWARD DRIER CONDITIONS
GIVEN LOW CONFIDENCE ON TIMING OF ANY PRECIP. GIVEN MODEL
DIFFERENCES IN THE LONG TERM LEANED MORE TOWARD PREVIOUS FORECAST
TEMPS OVER SAT AND SUN GIVEN MODEL DIFFERENCES.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECTING GRADUALLY IMPROVING CONDITIONS FROM WEST TO EAST DURING
THE DAY AS COLD FRONT CONTINUES TO MOVE WELL EAST OF THE AREA.
HIGH PRESSURE WILL BUILD EAST INTO THE REGION LATER TONIGHT INTO
WEDNESDAY. EXPECTING VFR CONDITIONS THROUGH THE LATTER HALF OF THE
TAF PERIOD. WINDS ARE EXPECTED TO CONTINUE OUT OF AROUND 350
DEGREES AT 10 TO 15 KNOTS THROUGH THE OVERNIGHT HOURS AND BEGIN TO
DIMINISH AFTER SUNRISE. LIGHT WINDS ALREADY BEING REPORTED JUST TO
THE WEST AND EXPECT THIS TO GET INTO OUR AREA TODAY.
.OUTLOOK...NON-VFR POSSIBLE IN EARLY MORNING FOG/HAZE WEDNESDAY.
&&
.MARINE...
QUICK UPDATE NEEDED TO COVER GUSTY WINDS ON THE LAKE. BUOY 45005
WAS REPORTING 20 KNOT WINDS WITH 4 FOOT WAVES. DECIDED TO HOIST
SMALL CRAFT ADVISORY FROM CONNEAUT ALL THE WAY TO THE ISLANDS TO
COVER THE HIGHER WAVE AND WIND SITUATION. SMALL CRAFT ADVISORY UP
UNTIL NOON.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR LEZ142>148.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...ABE
AVIATION...LOMBARDY
MARINE...LOMBARDY
AREA FORECAST DISCUSSION...CORRECTED
NWS NORMAN OK
314 PM CDT TUE MAY 22 2012
.DISCUSSION...
CONVECTION IS DEVELOPING AGAIN OVER THE HIGH PLAINS OF NEW MEXICO
AND IS CURRENTLY MOVING INTO CIMARRON COUNTY OKLAHOMA. SOME RECENT
RUNS OF THE LOCAL WRF AND THE HRRR HAVE SUGGESTED ENOUGH
POSSIBILITY OF CONVECTION INCREASING AND PERSISTING EAST AND
SOUTHEAST INTO WESTERN SECTIONS OF THE CWA THAT HAVE ADDED AN AREA
OF ISOLATED STORMS IN THE FIRST PERIOD OUT WEST ALTHOUGH AM
LEAVING THE POPS BELOW 20 PERCENT. THE EVENING SHIFT CAN CONTINUE
TO MONITOR THE TRENDS AND MAKE UPDATES IF NECESSARY. OTHERWISE...
HOT AND GENERALLY DRY WEATHER IS EXPECTED FOR A COUPLE OF DAYS AND
A WINDY DAY IS EXPECTED TOMORROW. A WIND ADVISORY MAY BE NECESSARY
FOR TOMORROW. SOMEWHAT COOLER TEMPERATURES ARE EXPECTED TOWARD THE
WEEKEND ALTHOUGH STILL WARM BY MID-LATE MAY STANDARDS. MEDIUM
RANGE MODELS ARE ALL SHOWING PRECIP DEVELOPING ON MONDAY ACROSS
THE NORTH AND WEST AHEAD OF A COLD FRONT... SO HAVE INTRODUCED
SOME POPS FOR MEMORIAL DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 91 68 91 / 0 0 10 10
HOBART OK 65 96 66 93 / 10 10 10 10
WICHITA FALLS TX 66 96 69 96 / 10 10 10 10
GAGE OK 64 94 62 90 / 10 10 10 10
PONCA CITY OK 67 90 69 88 / 0 0 10 10
DURANT OK 66 91 67 86 / 0 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
CORRECTED PRELIMINARY TEMPS/POPS
AREA FORECAST DISCUSSION
NWS NORMAN OK
1218 PM CDT TUE MAY 22 2012
.AVIATION...
ISOLATED CONVECTION PERSISTS THIS AFTERNOON... BUT IS EXPECTED TO
REMAIN SOUTH AND SOUTHEAST OF THE TAF SITES... SO NO SIGNIFICANT
AVIATION WEATHER CONCERNS ARE EXPECTED TODAY. SOUTH WINDS WILL
INCREASE WEDNESDAY MORNING WITH GUSTS NEAR OR ABOVE 30 KNOTS AT
MANY OF THE TAF LOCATIONS BY 18Z TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 1109 AM CDT TUE MAY 22 2012/
UPDATE...
WILL GO AHEAD AND ADD ISOLATED SHWR/TSTM WORDING ACROSS PORTIONS
OF SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTN. THIS
ACTIVITY IS ASSOCIATED WITH MCV AND SOME DIFFERENTIAL HEATING
BOUNDARIES THAT HAVE DEVELOPED FROM LAST EVENINGS CONVECTIONS
ACROSS WEST TEXAS. OTHERWISE... FORECAST IS IN GOOD SHAPE WITH
WARM AND BREEZY CONDITIONS EXPECTED THIS AFTN.
PREV DISCUSSION... /ISSUED 730 AM CDT TUE MAY 22 2012/
AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING. SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.
PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/
DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.
AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.
SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.
A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.
AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US. EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 90 67 90 / 10 10 10 10
HOBART OK 64 95 68 93 / 10 10 10 10
WICHITA FALLS TX 66 97 68 95 / 10 10 10 10
GAGE OK 62 93 62 92 / 10 10 10 10
PONCA CITY OK 65 90 68 91 / 10 10 10 10
DURANT OK 65 93 65 87 / 10 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1109 AM CDT TUE MAY 22 2012
.UPDATE...
WILL GO AHEAD AND ADD ISOLATED SHWR/TSTM WORDING ACROSS PORTIONS
OF SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTN. THIS
ACTIVITY IS ASSOCIATED WITH MCV AND SOME DIFFERENTIAL HEATING
BOUNDARIES THAT HAVE DEVELOPED FROM LAST EVENINGS CONVECTIONS
ACROSS WEST TEXAS. OTHERWISE... FORECAST IS IN GOOD SHAPE WITH
WARM AND BREEZY CONDITIONS EXPECTED THIS AFTN.
&&
.PREV DISCUSSION... /ISSUED 730 AM CDT TUE MAY 22 2012/
AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING. SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.
PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/
DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.
AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.
SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.
A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.
AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US. EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 85 65 90 67 / 10 10 10 10
HOBART OK 89 64 95 68 / 10 10 10 10
WICHITA FALLS TX 92 66 97 68 / 10 10 10 10
GAGE OK 89 62 93 62 / 10 10 10 10
PONCA CITY OK 83 65 90 68 / 10 10 10 10
DURANT OK 88 65 93 65 / 10 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/30
AREA FORECAST DISCUSSION
NWS NORMAN OK
730 AM CDT TUE MAY 22 2012
.AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING. SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.
&&
.PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/
DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.
AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.
SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.
A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.
AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US. EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 85 65 90 67 / 10 10 10 10
HOBART OK 89 64 95 68 / 10 10 10 10
WICHITA FALLS TX 92 66 97 68 / 10 10 10 10
GAGE OK 89 62 93 62 / 10 10 10 10
PONCA CITY OK 83 65 90 68 / 10 10 10 10
DURANT OK 88 65 93 65 / 10 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99/01
AREA FORECAST DISCUSSION
NWS NORMAN OK
418 AM CDT TUE MAY 22 2012
.DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.
AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.
SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.
A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.
AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US. EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 85 65 90 67 / 10 10 10 10
HOBART OK 89 64 95 68 / 30 10 10 10
WICHITA FALLS TX 92 66 97 68 / 30 10 10 10
GAGE OK 89 62 93 62 / 20 10 10 10
PONCA CITY OK 83 65 90 68 / 10 10 10 10
DURANT OK 88 65 93 65 / 10 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
803 AM EDT TUE MAY 22 2012
.SYNOPSIS...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE ACROSS
THE EASTERN U.S. THROUGH THURSDAY...BRINGING SEVERAL ROUNDS OF
SHOWERS AND A FEW THUNDERSTORMS. A SOUTHWEST FLOW OF WARMER AND
HUMID AIR WILL FOLLOW FOR FRIDAY...AND THE ABOVE NORMAL TEMPERATURES
WILL CONTINUE THROUGH THE UPCOMING WEEKEND. A WEAK COLD FRONT WILL
ATTEMPT TO PUSH SOUTHEAST THROUGH THE REGION SATURDAY AFTERNOON AND
EVENING...BUT COULD STALL OUT ACROSS OR JUST TO THE NORTH OF THE
REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
MOST OF THE EARLIER MDT TO HVY SHRA HAVE DISSIPATED ACROSS THE
CWA...WITH THE EXCEPTION OF THE NCENT MTNS WHERE A SMALL AREA OF
SHOWERS WAS DRIFTING SLOWLY TO THE NORTH.
NEARLY NORTH/SOUTH AXIS OF BOUNDARY LAYER THETA-E CONVERGENCE
EXTENDED FROM NCENT PENN...TO THE SCENT MTNS AND LAUREL HIGHLANDS
EARLY TODAY. 06Z RUC INDICATES THAT THIS AXIS WILL SHIFT A FEW
LAYERS OF COUNTIES TO THE WEST BY THIS AFTERNOON...WHILE A NOTABLE
AREA OF LLVL MOISTURE DIVERGENCE WILL DRIFT NE AND BECOME LOCATED
ACROSS THE SUSQ VALLEY DURING THE MID AFTERNOON HOURS.
THE MOST NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO
THE WESTERN HALF OF THE CWA INTO THE LATE AFTERNOON. THE APPROACH
OF A AN 850 MB TROUGH AND RIBBON OF SLIGHTLY STEEPER MID LEVEL
LAPSE RATES LATE THIS AFTERNOON AND TONIGHT WILL HELP TO SHIFT THE
AXIS OF MOST NUMEROUS SHOWERS AND SCTD TSRA TO THE SUSQ VALLEY
POINTS EAST FOR VERY LATE TODAY...INTO EARLY WED MORNING.
THE SLOW MOVEMENT OF THE SHOWERS AND STORMS TODAY /AND PERSISTENT
FOCUS AREA/ COULD LEAD TO SOME MODERATELY HEAVY ADDITIONAL RAINFALL
OF 0.5 TO 1.0 OF AN INCH. LESSER AMOUNTS OF RAIN ARE EXPECTED FOR
THE FAR NW CORNER OF THE CWA...AND ALSO FROM THE SUSQ VALLEY...EAST.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX.
&&
.SHORT TERM /WEDNESDAY/...
THE MEAN LARGE-SCALE TROUGH AT THE SFC AND ALOFT WILL CONTINUE TO
RESIDE RIGHT ALONG THE APPALACHIAN MTN CHAIN THROUGH AT LEAST
WEDNESDAY NIGHT...AS THE DEVELOPING UPPER LOW ACROSS THE TENN VALLEY
LIFTS SLOWLY NE ACROSS THE VIRGINIAS AND PENN. THE PRIMARY AXIS OF
LLVL PWATS AND ASSOCIATED THETA-E CONVERGENCE SHOULD SHIFT SLIGHTLY
TO THE EAST ON WEDNESDAY /BECOMING LOCATED FROM THE UPPER SUSQ
VALLEY...TO THE SCENT MTNS AND LAURELS/...ALONG AND JUST TO THE EAST
OF THE WEAKENING UPPER LOW TRACK.
INSTABILITY RAMPS UP A FEW HUNDRED J/KG IN THE CAPE DEPT
WEDNESDAY...WITH THE BEST CONVECTIVE POTENTIAL ALONG AND TO THE SE
OF A LINE FROM KIPT TO KAOO. VERY WEAK WINDS IN THE LOWEST 15 KFT OF
THE ATMOSPHERE WILL KEEP THE EHI/S ON THE VERY LOW SIDE...WITH THE
MAIN CHARACTERISTIC OF THE CONVECTION BEING IT/S SLOW MOVEMENT AND
LOCALIZED HEAVY RAIN POTENTIAL. PWATS ARE NOT TREMENDOUSLY HIGH -
ONLY 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AND WITH THE EXTENSIVE
CLOUD COVER...HIGH CAPES OF 2000 J/KG OR MORE WILL BE DIFFICULT TO
COME BY. STILL...THE 00Z GEFS AND 03Z SREF TARGET THE SCENT MTNS AND
MID SUSQ VALLEY FOR ABOUT A 60 PERCENT CHC FOR SFC BASED CAPES TO
EXCEED 1200 J/KG.
BASIN AVG RAINFALL AMOUNTS FOR THE NEXT 36 HOURS WILL BE MAINLY IN
THE 0.5 TO 1.0 RANGE. AREAS RECEIVING A FEW TSRA COULD SEE NEARLY
1.5 INCHES /AS INDICATED BY SEVERAL SREF AND GEFS PLUME MEMBERS/.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A SLOWLY FILLING UPPER LOW WILL DRIFT NE FROM THE CENTRAL
APPALACHIANS AND CROSS SERN PENN ON THURSDAY. WED EVENING
CONVECTION WILL QUICKLY WANE BY 04Z WITH CLOUDY SKIES...LIGHT
WIND AND AREAS OF FOG FOLLOWING FOR THE REST OF THE OVERNIGHT HOURS.
ISOLATED TO SCATTERED...MAINLY AFTERNOON AND EARLY EVENING SHRA
AND TSRA WILL OCCUR THURSDAY AND FRIDAY.
GFS AND OTHERS ARE MORE IN LINE WITH KEEPING FRONT NORTH OF OUR AREA
THIS COMING HOLIDAY WEEKEND...WHILE THE LATEST EC MAKES AN ATTEMPT
TO PUSH THE SHALLOW FRONT TO THE SOUTHERN TIER OF PA SATURDAY NIGHT.
A LARGE POOL OF VERY WARM AIR AT THE SFC AND ALOFT FORMS ACROSS THE
LOWER-MID MISS VALLEY AND OHIO RIVER VALLEY OVER THE UPCOMING
WEEKEND.
THE SOUTHERN EDGE OF WNW FLOW ALOFT /FROM THE GREAT LAKES TO THE
SOUTHERN NEW ENGLAND COAST/ WILL TRANSPORT SOME RIPPLES OF ENERGY
ALOFT ALONG/ABOVE THE LLVL FRONTAL BOUNDARY...POSSIBLY SPARKING SOME
SHOWERS AND TSRA. WE COULD EVEN SEE AN MCS OR TWO TRACK SE INTO THE
WRN AND CENTRAL CWA FROM THE UPPER LAKES REGION SATURDAY MORNING
/AND AGAIN SUNDAY/ WITHIN THE CHANNEL OF PWATS RANGING FROM 32-36MM.
GFS BEST ILLUSTRATES THE POTENTIAL /VIA ITS 500 MB VORT PANELS/ FOR
A FEW RING OF FIRE MCS/S TO SLIDE SE ACROSS MAINLY NRN AND WESTERN
PART OF PENN.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE THROUGH
THURSDAY...BRINGING SEVERAL ROUNDS OF SHOWERS AND A FEW
THUNDERSTORMS.
WIDESPREAD IFR TO MVFR CIGS ACROSS CENTRAL PA THIS MORNING...WILL
IMPROVE SLIGHTLY THROUGH LATE MORNING WITH MOST LOCATIONS BECOMING
MVFR BY 15Z. SHOWERS AGAIN EXPECTED TO DEVELOP OVER MUCH OF THE
REGION BY LATE MORNING...PERSISTING THROUGH THE AFTERNOON - AND
EVEN A RUMBLE OF THUNDER POSS THIS AFTERNOON MAINLY SOUTH /BUT CHC
TOO LOW TO MENTION IN TAFS ATTM/. CIGS SHOULD CONTINUE TO
GRADUALLY IMPROVE THIS AFTERNOON WITH INCREASING AMOUNTS OF VFR
CIGS SPREADING IN FROM THE WEST.
WEAK FRONT PUSHES ACROSS CWA LATE TODAY AND TONIGHT...WITH VFR
CONDITIONS DURING THE EVENING HOURS. BUT PLENTY OF LOW LEVEL
MOISTURE WILL ALLOW FOG AND LOW CIGS TO DEVELOP AFTER
MIDNIGHT...AGAIN RESTRICTING FLYING.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
455 AM EDT TUE MAY 22 2012
.SYNOPSIS...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE ACROSS
THE EASTERN U.S. THROUGH THURSDAY...BRINGING SEVERAL ROUNDS OF
SHOWERS AND A FEW THUNDERSTORMS. A SOUTHWEST FLOW OF WARMER AND
HUMID AIR WILL FOLLOW FOR FRIDAY...AND THE ABOVE NORMAL TEMPERATURES
WILL CONTINUE THROUGH THE UPCOMING WEEKEND. A WEAK COLD FRONT WILL
ATTEMPT TO PUSH SOUTHEAST THROUGH THE REGION SATURDAY AFTERNOON AND
EVENING...BUT COULD STALL OUT ACROSS OR JUST TO THE NORTH OF THE
REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
MOST OF THE EARLIER MDT TO HVY SHRA HAVE DISSIPATED ACROSS THE
CWA...WITH THE EXCEPTION OF THE NCENT MTNS WHERE A SMALL AREA OF
SHOWERS WAS DRIFTING SLOWLY TO THE NORTH.
NEARLY NORTH/SOUTH AXIS OF BOUNDARY LAYER THETA-E CONVERGENCE
EXTENDED FROM NCENT PENN...TO THE SCENT MTNS AND LAUREL HIGHLANDS
EARLY TODAY. 06Z RUC INDICATES THAT THIS AXIS WILL SHIFT A FEW
LAYERS OF COUNTIES TO THE WEST BY THIS AFTERNOON...WHILE A NOTABLE
AREA OF LLVL MOISTURE DIVERGENCE WILL DRIFT NE AND BECOME LOCATED
ACROSS THE SUSQ VALLEY DURING THE MID AFTERNOON HOURS.
THE MOST NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO
THE WESTERN HALF OF THE CWA INTO THE LATE AFTERNOON. THE APPROACH
OF A AN 850 MB TROUGH AND RIBBON OF SLIGHTLY STEEPER MID LEVEL
LAPSE RATES LATE THIS AFTERNOON AND TONIGHT WILL HELP TO SHIFT THE
AXIS OF MOST NUMEROUS SHOWERS AND SCTD TSRA TO THE SUSQ VALLEY
POINTS EAST FOR VERY LATE TODAY...INTO EARLY WED MORNING.
THE SLOW MOVEMENT OF THE SHOWERS AND STORMS TODAY /AND PERSISTENT
FOCUS AREA/ COULD LEAD TO SOME MODERATELY HEAVY ADDITIONAL RAINFALL
OF 0.5 TO 1.0 OF AN INCH. LESSER AMOUNTS OF RAIN ARE EXPECTED FOR
THE FAR NW CORNER OF THE CWA...AND ALSO FROM THE SUSQ VALLEY...EAST.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX.
&&
.SHORT TERM /WEDNESDAY/...
THE MEAN LARGE-SCALE TROUGH AT THE SFC AND ALOFT WILL CONTINUE TO
RESIDE RIGHT ALONG THE APPALACHIAN MTN CHAIN THROUGH AT LEAST
WEDNESDAY NIGHT...AS THE DEVELOPING UPPER LOW ACROSS THE TENN VALLEY
LIFTS SLOWLY NE ACROSS THE VIRGINIAS AND PENN. THE PRIMARY AXIS OF
LLVL PWATS AND ASSOCIATED THETA-E CONVERGENCE SHOULD SHIFT SLIGHTLY
TO THE EAST ON WEDNESDAY /BECOMING LOCATED FROM THE UPPER SUSQ
VALLEY...TO THE SCENT MTNS AND LAURELS/...ALONG AND JUST TO THE EAST
OF THE WEAKENING UPPER LOW TRACK.
INSTABILITY RAMPS UP A FEW HUNDRED J/KG IN THE CAPE DEPT
WEDNESDAY...WITH THE BEST CONVECTIVE POTENTIAL ALONG AND TO THE SE
OF A LINE FROM KIPT TO KAOO. VERY WEAK WINDS IN THE LOWEST 15 KFT OF
THE ATMOSPHERE WILL KEEP THE EHI/S ON THE VERY LOW SIDE...WITH THE
MAIN CHARACTERISTIC OF THE CONVECTION BEING IT/S SLOW MOVEMENT AND
LOCALIZED HEAVY RAIN POTENTIAL. PWATS ARE NOT TREMENDOUSLY HIGH -
ONLY 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AND WITH THE EXTENSIVE
CLOUD COVER...HIGH CAPES OF 2000 J/KG OR MORE WILL BE DIFFICULT TO
COME BY. STILL...THE 00Z GEFS AND 03Z SREF TARGET THE SCENT MTNS AND
MID SUSQ VALLEY FOR ABOUT A 60 PERCENT CHC FOR SFC BASED CAPES TO
EXCEED 1200 J/KG.
BASIN AVG RAINFALL AMOUNTS FOR THE NEXT 36 HOURS WILL BE MAINLY IN
THE 0.5 TO 1.0 RANGE. AREAS RECEIVING A FEW TSRA COULD SEE NEARLY
1.5 INCHES /AS INDICATED BY SEVERAL SREF AND GEFS PLUME MEMBERS/.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A SLOWLY FILLING UPPER LOW WILL DRIFT NE FROM THE CENTRAL
APPALACHIANS AND CROSS SERN PENN ON THURSDAY. WED EVENING
CONVECTION WILL QUICKLY WANE BY 04Z WITH CLOUDY SKIES...LIGHT
WIND AND AREAS OF FOG FOLLOWING FOR THE REST OF THE OVERNIGHT HOURS.
ISOLATED TO SCATTERED...MAINLY AFTERNOON AND EARLY EVENING SHRA
AND TSRA WILL OCCUR THURSDAY AND FRIDAY.
GFS AND OTHERS ARE MORE IN LINE WITH KEEPING FRONT NORTH OF OUR AREA
THIS COMING HOLIDAY WEEKEND...WHILE THE LATEST EC MAKES AN ATTEMPT
TO PUSH THE SHALLOW FRONT TO THE SOUTHERN TIER OF PA SATURDAY NIGHT.
A LARGE POOL OF VERY WARM AIR AT THE SFC AND ALOFT FORMS ACROSS THE
LOWER-MID MISS VALLEY AND OHIO RIVER VALLEY OVER THE UPCOMING
WEEKEND.
THE SOUTHERN EDGE OF WNW FLOW ALOFT /FROM THE GREAT LAKES TO THE
SOUTHERN NEW ENGLAND COAST/ WILL TRANSPORT SOME RIPPLES OF ENERGY
ALOFT ALONG/ABOVE THE LLVL FRONTAL BOUNDARY...POSSIBLY SPARKING SOME
SHOWERS AND TSRA. WE COULD EVEN SEE AN MCS OR TWO TRACK SE INTO THE
WRN AND CENTRAL CWA FROM THE UPPER LAKES REGION SATURDAY MORNING
/AND AGAIN SUNDAY/ WITHIN THE CHANNEL OF PWATS RANGING FROM 32-36MM.
GFS BEST ILLUSTRATES THE POTENTIAL /VIA ITS 500 MB VORT PANELS/ FOR
A FEW RING OF FIRE MCS/S TO SLIDE SE ACROSS MAINLY NRN AND WESTERN
PART OF PENN.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SEMI-PERSISTENT N-S AXIS OF RAIN SPLITTING CWA THIS
MORNING...CONTINUES TO GRADUALLY WEAKEN. OUTSIDE OF THAT...ANY
PRECIP WILL BE ISOLATED AND LIGHT THROUGH THE OVERNIGHT HOURS.
MVFR TO IFR CONDITIONS HAVE SETTLED IN WITH LOWERING CIGS IN VERY
MOIST AIRMASS. EXPECT THESE TO DROP EVEN FURTHER OVERNIGHT...WITH
WIDESPREAD IFR-LIFR LINGERING INTO THE MID MORNING.
SOME DIURNAL IMPROVEMENT IN CONDITIONS ON TUESDAY AS CIGS LIFT TO
MVFR DURING THE MID/LATE MORNING...EVENTUALLY BECOMING VFR IN MANY
PLACES DURING THE AFTERNOON AS UPPER FLOW BECOMES A BIT MORE
SOUTHERLY IN ADVANCE OF NEWLY DEVELOPING TN VALLEY UPPER LEVEL
LOW. WITH THE POTENTIAL INCREASE IN CIGS AND VSBYS WILL BE
INCREASING CHANCES OF SHOWERS AND POSSIBLE TSRA...BRINGING LOCAL
RESTRICTIONS.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...JUNG/RXR
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
550 PM CDT TUE MAY 22 2012
.AVIATION...
ISOLATED CHANCE FOR A THUNDERSTORM THROUGH 03Z. OTHERWISE...VFR
EXPECTED. THERE IS AN OUTSIDE CHANCE THAT THE SEA BREEZE MAY
BECOME ACTIVE WEDNESDAY AFTERNOON AFTER 21Z. FOR NOW THE CHANCES
ARE 10 PERCENT AND WILL NOT MENTION IN THE FORECAST.
40
&&
.PREV DISCUSSION... /ISSUED 336 PM CDT TUE MAY 22 2012/
DISCUSSION...
SHRA AND A FEW TSRA HAVE FORMED EARLIER TODAY THAN YESTERDAY IN
MADISON...WALKER...SAN JACINTO AND LIBERTY COUNTIES AND SLIGHTLY
MORE COVERAGE AS WELL. HAVE NUDGED POPS UP AROUND THOSE AREAS FOR
THE REST OF THIS AFTERNOON AND INTO THE MID EVENING HOURS.
CONVECTIVE TEMPERATURES WERE MET AND UPSTREAM DISTURBANCE HELPED
THIS ALONG TODAY. STILL EXPECT TSRA TO BE MOSTLY DIURNAL AND
SHOULD DIMINISH AFTER SUNSET. HRRR REFLECTIVITY FIELD FORECASTS
AGREE WITH THIS ASSESSMENT AS WELL.
GALVESTON HIT 90F AT 1252PM WHICH TIED THE RECORD HIGH FOR TODAY.
COULD HAVE GONE A LITTLE HIGHER BUT WINDS SHIFTED ONSHORE WITH A
SEA BREEZE JUST A FEW HOURS EARLIER THAN EXPECTED TODAY.
AS SURFACE HIGH OVER NW GULF MOVES SLOWLY AWAY AND LEE TROUGH
DEVELOPS TOMORROW ONSHORE WINDS WILL INCREASE. PWATS REMAIN AROUND
NORMAL FOR MARCH-MAY VALUES. MEAN 1000-700MB SOUTHWESTERLY TO
SOUTHWESTERLY WINDS SHOULD INCREASE THE CAPPING INVERSION LEADING
TO A DRY SPELL FOR THE NEXT SEVERAL DAYS. GULF MOISTURE DOES NOT
LOOK TO BE FULLY TAPPED UNTIL SATURDAY MORNING BUT REMAINS TRAPPED
UNDERNEATH GIANT SUBSIDENCE INVERSION AS UPPER RIDGING TAKES HOLD
OVER THE EAST HALF OF THE COUNTRY. COULD SEE A FEW VERY LOW TOPPED
-SHRA AT TIMES IN THE EXTENDED PERIOD UNDER THE CAP BUT NOT
COVERAGE WOULD BE ISOLATED AT BEST AND AMOUNTS VERY VERY LOW SO
WILL LEAVE OUT MENTION OF PCPN IN THE EXTENDED. VERY LITTLE CHANGE
IN MAX TEMPS THE NEXT FEW DAYS WITH ONLY SOME VERY TINY MODERATION
AS LOW LEVEL HUMIDITY AND ONSHORE FLOW COMMENCES. MORNING LOWS TO
CLIMB A TAD AS RH INCREASES.
NOT BUYING GFS SOLUTION IN LONG RANGE OF LOOP-D-LOOPING SFC LOW
RETURNING FROM THE ATLANTIC...PREFER ECMWF LIKE SOLUTION OF
CONTINUING TROUGHING OUT THAT WAY. AS A WISE FCSTR ONCE SAID ABOUT
THE LONG RANGE TROPICS...IF IT AINT IN THE ECMWF YET I AINT
BELIEVING IT. GOOD WORDS GENERALLY. 04
AVIATION...
TOOK OUT THE MENTION OF CB/PCPN FOR THIS AFTN WITH THE 18Z TAFS AS
THERE WAS SOME UNCERTAINTY CONCERNING THE START TIME TO THE DEVEL-
OPMENT. BUT IT LOOKS LIKE THINGS ARE GOING SOONER THAN EXPECTED SO
WILL LIKELY BE ADDING VCTS/CB IN THE TAFS VIA AMENDMENTS AS STORMS
APPROACH THE VARIOUS SITES. OTHERWISE STILL EXPECTING PCPN TO WANE
WITH THE LOSS OF DAYTIME HEATING. MOSTLY VFR OVERNIGHT WITH PATCHY
BR IN THE USUAL SPOTS (CXO/LBX). ONSHORE FLOW PATTERN EVOLVING THE
NEXT FEW DAYS COULD MAKE FOR A SLIGHTLY MORE ACTIVE SEABREEZE. 41
MARINE...
NOT A LOT OF CHANGES TO THE GOING FCST OF DEVELOPING ONSHORE WINDS
THE NEXT FEW DAYS. WIND SPEEDS/WAVE HEIGHTS NOT EXPECTED TO BE AT/
NEAR CAUTION/ADVISORY LEVELS UNTIL LATE WEDS AS THE PRESSURE GRAD-
IENT TIGHTENS IN RESPONSE TO THE NEXT SYSTEM DEEPENING ACROSS/OVER
THE CENTRAL PLAINS. AS THIS PATTERN IS PROGGED TO PERSIST THE REST
OF THE WEEK...WE COULD ALSO SEE WAVE HEIGHTS INCREASE STEADILY FOR
THIS SAME TIME FRAME. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 67 92 68 91 71 / 30 10 10 10 10
HOUSTON (IAH) 70 90 70 90 73 / 20 10 10 10 10
GALVESTON (GLS) 76 86 76 86 78 / 10 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
336 PM CDT TUE MAY 22 2012
.DISCUSSION...
SHRA AND A FEW TSRA HAVE FORMED EARLIER TODAY THAN YESTERDAY IN
MADISON...WALKER...SAN JACINTO AND LIBERTY COUNTIES AND SLIGHTLY
MORE COVERAGE AS WELL. HAVE NUDGED POPS UP AROUND THOSE AREAS FOR
THE REST OF THIS AFTERNOON AND INTO THE MID EVENING HOURS.
CONVECTIVE TEMPERATURES WERE MET AND UPSTREAM DISTURBANCE HELPED
THIS ALONG TODAY. STILL EXPECT TSRA TO BE MOSTLY DIURNAL AND
SHOULD DIMINISH AFTER SUNSET. HRRR REFLECTIVITY FIELD FORECASTS
AGREE WITH THIS ASSESSMENT AS WELL.
GALVESTON HIT 90F AT 1252PM WHICH TIED THE RECORD HIGH FOR TODAY.
COULD HAVE GONE A LITTLE HIGHER BUT WINDS SHIFTED ONSHORE WITH A
SEA BREEZE JUST A FEW HOURS EARLIER THAN EXPECTED TODAY.
AS SURFACE HIGH OVER NW GULF MOVES SLOWLY AWAY AND LEE TROUGH
DEVELOPS TOMORROW ONSHORE WINDS WILL INCREASE. PWATS REMAIN AROUND
NORMAL FOR MARCH-MAY VALUES. MEAN 1000-700MB SOUTHWESTERLY TO
SOUTHWESTERLY WINDS SHOULD INCREASE THE CAPPING INVERSION LEADING
TO A DRY SPELL FOR THE NEXT SEVERAL DAYS. GULF MOISTURE DOES NOT
LOOK TO BE FULLY TAPPED UNTIL SATURDAY MORNING BUT REMAINS TRAPPED
UNDERNEATH GIANT SUBSIDENCE INVERSION AS UPPER RIDGING TAKES HOLD
OVER THE EAST HALF OF THE COUNTRY. COULD SEE A FEW VERY LOW TOPPED
-SHRA AT TIMES IN THE EXTENDED PERIOD UNDER THE CAP BUT NOT
COVERAGE WOULD BE ISOLATED AT BEST AND AMOUNTS VERY VERY LOW SO
WILL LEAVE OUT MENTION OF PCPN IN THE EXTENDED. VERY LITTLE CHANGE
IN MAX TEMPS THE NEXT FEW DAYS WITH ONLY SOME VERY TINY MODERATION
AS LOW LEVEL HUMIDITY AND ONSHORE FLOW COMMENCES. MORNING LOWS TO
CLIMB A TAD AS RH INCREASES.
NOT BUYING GFS SOLUTION IN LONG RANGE OF LOOP-D-LOOPING SFC LOW
RETURNING FROM THE ATLANTIC...PREFER ECMWF LIKE SOLUTION OF
CONTINUING TROUGHING OUT THAT WAY. AS A WISE FCSTR ONCE SAID ABOUT
THE LONG RANGE TROPICS...IF IT AINT IN THE ECMWF YET I AINT
BELIEVING IT. GOOD WORDS GENERALLY. 04
.AVIATION...
TOOK OUT THE MENTION OF CB/PCPN FOR THIS AFTN WITH THE 18Z TAFS AS
THERE WAS SOME UNCERTAINTY CONCERNING THE START TIME TO THE DEVEL-
OPMENT. BUT IT LOOKS LIKE THINGS ARE GOING SOONER THAN EXPECTED SO
WILL LIKELY BE ADDING VCTS/CB IN THE TAFS VIA AMENDMENTS AS STORMS
APPROACH THE VARIOUS SITES. OTHERWISE STILL EXPECTING PCPN TO WANE
WITH THE LOSS OF DAYTIME HEATING. MOSTLY VFR OVERNIGHT WITH PATCHY
BR IN THE USUAL SPOTS (CXO/LBX). ONSHORE FLOW PATTERN EVOLVING THE
NEXT FEW DAYS COULD MAKE FOR A SLIGHTLY MORE ACTIVE SEABREEZE. 41
&&
.MARINE...
NOT A LOT OF CHANGES TO THE GOING FCST OF DEVELOPING ONSHORE WINDS
THE NEXT FEW DAYS. WIND SPEEDS/WAVE HEIGHTS NOT EXPECTED TO BE AT/
NEAR CAUTION/ADVISORY LEVELS UNTIL LATE WEDS AS THE PRESSURE GRAD-
IENT TIGHTENS IN RESPONSE TO THE NEXT SYSTEM DEEPENING ACROSS/OVER
THE CENTRAL PLAINS. AS THIS PATTERN IS PROGGED TO PERSIST THE REST
OF THE WEEK...WE COULD ALSO SEE WAVE HEIGHTS INCREASE STEADILY FOR
THIS SAME TIME FRAME. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 92 67 92 68 91 / 20 30 10 10 10
HOUSTON (IAH) 94 70 90 70 90 / 20 20 10 10 10
GALVESTON (GLS) 90 76 86 76 86 / 10 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...04
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
100 PM CDT TUE MAY 22 2012
.AVIATION...
THE ONLY AVIATION WEATHER CONCERNS TODAY WILL ISOLATED SHOWERS
THIS AFTERNOON ASSOCIATED WITH A WEAK MCV...CURRENTLY WEST OF THE
TAF SITES. THE MCV WILL CONTINUE ON A SOUTHEAST TRACK AND A FEW
SHOWERS ON THE PERIPHERY OF THE CIRCULATION MAY GRAZE THE METROPLEX
TAF SITES WITH A SLIGHTLY BETTER CHANCE OF A BRIEF SHOWER AT WACO.
SINCE IMPACTS WITH ANY OF THESE ELEVATED SHOWERS SHOULD BE
MINIMAL...WILL NOT MENTION IN THIS TAF PACKAGE. ANY SHOWERS THAT
DO MANAGE TO FORM SHOULD DISSIPATE WITH THE LOSS OF SURFACE
HEATING. EXPECT VFR CONDITIONS TONIGHT AND WEDNESDAY.
A SOUTH WIND WILL PREVAIL BETWEEN 5 AND 11 KNOTS THIS AFTERNOON
AND TONIGHT. SOUTHERLY WINDS WILL INCREASE SIGNIFICANTLY WEDNESDAY
AS SURFACE LOW PRESSURE DEEPENS ACROSS THE HIGH PLAINS. SUSTAINED
WIND SPEEDS WILL RANGE FROM 15 TO 20 MPH WITH SOME HIGHER GUSTS.
79
&&
.UPDATE...
THE WEAK SURFACE FRONT SITS NEAR A LINE FROM LEON TO STEPHENVILLE
TO BRYSON. 925 MB FLOW SHOWS WEAK CONVERGENCE NEAR THE
FRONT...WHICH BY THIS AFTERNOON SHOULD BE LOCATED NEAR A BOWIE TO
FORT WORTH TO PALESTINE LINE. MORNING MODELS SUCH AS HRRR AND NAM
AND GFS ARE A BIT MORE AGGRESSIVE DEVELOPING SOME CONVECTION ALONG
THIS LINE SO HAVE ADDED ISOLD POPS FARTHER EAST THAN PREVIOUS.
OTHERWISE...FEW CHANGES TO THE PACKAGE. 84
&&
.PREV DISCUSSION... /ISSUED 340 AM CDT TUE MAY 22 2012/
CIRRUS BLOWOFF FROM THE THUNDERSTORMS IN THE PANHANDLE AND SOUTH
PLAINS OF WEST TEXAS CONTINUE TO SPREAD SOUTHEAST ACROSS NORTH
TEXAS THIS MORNING. EXPECT THESE CLOUDS TO THIN LATER THIS
MORNING...AND WE SHOULD SEE TEMPERATURES CLIMB INTO THE MID 80S
NORTHEAST TO MID 90S SOUTH THIS AFTERNOON. AS A SHORTWAVE MOVES
SOUTHEAST OUT OF THE PANHANDLE...A FEW THUNDERSTORMS MAY AFFECT
THE WESTERN COUNTIES. THUS HAVE LEFT LOW POPS THERE. OTHERWISE...
IT LOOKS LIKE A WARM AND DRY PERIOD WILL OCCUR THROUGH THE
WEEKEND. AS A SURFACE TROUGH DEVELOPS ACROSS THE NORTHERN AND
CENTRAL PLAINS...WE WILL SEE SOUTHERLY WINDS INCREASE WEDNESDAY
AND THURSDAY. AN UPPER LEVEL RIDGE WILL DEVELOP ACROSS THE SOUTHEASTERN
UNITED STATES FRIDAY INTO THE WEEKEND. AS LOW LEVEL MOISTURE
INCREASES...CAN NOT RULE OUT SOME ISOLATED AFTERNOON/EARLY EVENING
THUNDERSTORMS SUNDAY AND MONDAY...BUT RAIN CHANCES ARE NOT HIGH
ENOUGH TO MENTION YET.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 91 69 93 71 95 / 10 10 5 10 10
WACO, TX 93 67 95 71 95 / 20 10 5 10 10
PARIS, TX 85 62 89 67 88 / 5 5 5 10 10
DENTON, TX 91 68 93 71 95 / 10 10 5 10 10
MCKINNEY, TX 90 66 92 70 92 / 10 10 5 10 10
DALLAS, TX 92 70 93 71 94 / 10 10 5 10 10
TERRELL, TX 88 66 92 69 93 / 10 10 5 10 10
CORSICANA, TX 91 67 92 70 93 / 10 10 5 10 10
TEMPLE, TX 92 66 93 70 94 / 20 5 5 10 5
MINERAL WELLS, TX 91 65 94 68 97 / 20 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
79/84
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1042 AM CDT TUE MAY 22 2012
.UPDATE...
THE WEAK SURFACE FRONT SITS NEAR A LINE FROM LEON TO STEPHENVILLE
TO BRYSON. 925 MB FLOW SHOWS WEAK CONVERGENCE NEAR THE
FRONT...WHICH BY THIS AFTERNOON SHOULD BE LOCATED NEAR A BOWIE TO
FORT WORTH TO PALESTINE LINE. MORNING MODELS SUCH AS HRRR AND NAM
AND GFS ARE A BIT MORE AGGRESSIVE DEVELOPING SOME CONVECTION ALONG
THIS LINE SO HAVE ADDED ISOLD POPS FARTHER EAST THAN PREVIOUS.
OTHERWISE...FEW CHANGES TO THE PACKAGE. 84
&&
.AVIATION...
CONCERNS...NONE.
VFR CONDITIONS ARE EXPECTED TO PREVAIL. LIGHT AND VARIABLE WINDS
AT THE BEGINNING OF THE TAF PERIOD WILL BECOME SOUTH-SOUTHEASTERLY
DURING THE MORNING HOURS. WIND SPEEDS TODAY WILL REMAIN AT OR
BELOW 10 KTS. HOWEVER...WIND SPEEDS WILL INCREASE WEDNESDAY
MORNING WITH SUSTAINED SPEEDS OF 15-20 KTS...GUSTING UP TO 30
KTS...FOR MUCH OF THE DAY TOMORROW. THERE IS ANOTHER SMALL CHANCE
FOR SHOWERS AND THUNDERSTORMS TODAY BUT IF ANY STORMS DO DEVELOP
THEY WOULD LIKELY REMAIN WEST OF THE TAF TERMINALS.
82/JLD
&&
.PREV UPDATE...
.UPDATE...
A QUICK UPDATE WAS DONE TO ADJUST THE POPS IN THE WEST THIS
MORNING A LITTLE TO ACCOUNT FOR THE SHOWERS ASSOCIATED WITH THE
VORTEX NORTHWEST OF ABILENE.
58
&&
.PREV DISCUSSION... /ISSUED 340 AM CDT TUE MAY 22 2012/
CIRRUS BLOWOFF FROM THE THUNDERSTORMS IN THE PANHANDLE AND SOUTH
PLAINS OF WEST TEXAS CONTINUE TO SPREAD SOUTHEAST ACROSS NORTH
TEXAS THIS MORNING. EXPECT THESE CLOUDS TO THIN LATER THIS
MORNING...AND WE SHOULD SEE TEMPERATURES CLIMB INTO THE MID 80S
NORTHEAST TO MID 90S SOUTH THIS AFTERNOON. AS A SHORTWAVE MOVES
SOUTHEAST OUT OF THE PANHANDLE...A FEW THUNDERSTORMS MAY AFFECT
THE WESTERN COUNTIES. THUS HAVE LEFT LOW POPS THERE. OTHERWISE...
IT LOOKS LIKE A WARM AND DRY PERIOD WILL OCCUR THROUGH THE
WEEKEND. AS A SURFACE TROUGH DEVELOPS ACROSS THE NORTHERN AND
CENTRAL PLAINS...WE WILL SEE SOUTHERLY WINDS INCREASE WEDNESDAY
AND THURSDAY. AN UPPER LEVEL RIDGE WILL DEVELOP ACROSS THE SOUTHEASTERN
UNITED STATES FRIDAY INTO THE WEEKEND. AS LOW LEVEL MOISTURE
INCREASES...CAN NOT RULE OUT SOME ISOLATED AFTERNOON/EARLY EVENING
THUNDERSTORMS SUNDAY AND MONDAY...BUT RAIN CHANCES ARE NOT HIGH
ENOUGH TO MENTION YET.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 91 69 93 71 95 / 10 10 5 10 10
WACO, TX 93 67 95 71 95 / 20 10 5 10 10
PARIS, TX 85 62 89 67 88 / 5 5 5 10 10
DENTON, TX 91 68 93 71 95 / 10 10 5 10 10
MCKINNEY, TX 90 66 92 70 92 / 10 10 5 10 10
DALLAS, TX 92 70 93 71 94 / 10 10 5 10 10
TERRELL, TX 88 66 92 69 93 / 10 10 5 10 10
CORSICANA, TX 91 67 92 70 93 / 10 10 5 10 10
TEMPLE, TX 92 66 93 70 94 / 20 5 5 10 5
MINERAL WELLS, TX 91 65 94 68 97 / 20 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1149 PM CDT MON MAY 21 2012
.DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/
&&
.AVIATION...
LARGE COMPLEX OF THUNDERSTORMS MOVING SOUTHEAST AT 20 KTS OUT OF
THE PANHANDLE WILL LIKELY WEAKEN AND DISSIPATE AS IT APPROACHES WEST
CENTRAL TEXAS LATE TONIGHT...ACCORDING TO THE RUC NAM AND GFS
MODELS. HOWEVER IF THE COMPLEX DOES SURVIVE MOVING OFF THE CAPROCK
...IT WOULD STILL TAKE UNTIL AFTER 12Z TO AFFECT KSJT AND KABI.
WILL CONTINUE VFR CONDITIONS IN THE TAFS.
04
&&
.PREV DISCUSSION... /ISSUED 948 PM CDT MON MAY 21 2012/
DISCUSSION...
HAVE UPDATED THE FORECAST TO TAKE OUT THE EARLY MENTION OF
THUNDERSTORMS...AND MAKE SLIGHT ADJUSTMENTS TO THE POPS/WX AFTER
MIDNIGHT TONIGHT. LATEST MODEL GUIDANCE SUGGESTS THE MCS THAT HAS
FORMED NORTHWEST OF LUBBOCK THIS EVENING COULD SURVIVE LONG ENOUGH
TO MAKE IT INTO OUR NORTHWEST COUNTIES AFTER MIDNIGHT TONIGHT...
AND POSSIBLY EVEN RESULT IN ISOLATED SHOWERS/THUNDERSTORMS MAKING
IT TO NEAR THE ABILENE AREA TOWARDS SUNRISE. NO OTHER CHANGES
WERE MADE TO THE FORECAST. UPDATED PRODUCTS WILL BE OUT
SOON...GRIDS HAVE BEEN SENT AND PUBLISHED. 20
PREV DISCUSSION... /ISSUED 611 PM CDT MON MAY 21 2012/
DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/
AVIATION...
ISOLATED SHOWERS POSSIBLE NEAR BRADY AS AN OUTFLOW BOUNDARY MOVES
THROUGH AROUND 1Z...BUT TOO REMOTE TO INCLUDE IN THE KBBD TAF. POTENTIAL
EXISTS FOR A FEW PATCHES OF STRATUS POSSIBLE TOWARD DAYBREAK...MAINLY
ALONG THE I-10 CORRIDOR. HOWEVER MOST AREAS WILL REMAIN VFR AND
WILL KEEP TAFS VFR.
04
PREV DISCUSSION... /ISSUED 311 PM CDT MON MAY 21 2012/
SHORT TERM...
STALLED COLD FRONT IS LOCATED ALONG A LINE FROM NEAR SWEETWATER...TO
JUST NORTH OF ABILENE. TOWERING CUMULUS IS EVIDENT ON VISIBLE
SATELLITE ALONG AND AHEAD OF THE BOUNDARY...OVER THE SOUTHERN BIG
COUNTRY AND NORTHERN CONCHO VALLEY. SHOWERS ARE STRUGGLING TO
DEVELOP THIS AFTERNOON...BUT AS CONTINUED HEATING HELPS TO DECREASE
THE CAP LATER THIS AFTERNOON...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THE BIG COUNTRY AND CONCHO
VALLEY. EXPECT MOST OF THE ACTIVITY TO QUICKLY DISSIPATE SHORTLY
AFTER SUNSET. THE NEXT MAIN ISSUE IS WHETHER AN MCS WILL DEVELOP
OVER THE SOUTH PLAINS REGION...AND TRY TO MOVE INTO AT LEAST THE
NORTHWEST PORTIONS OF WEST CENTRAL TEXAS EARLY TUESDAY MORNING. FOR
NOW...HAVE SLIGHT CHANCE POPS ACROSS BIG COUNTRY AFTER 06Z...WITH
MOST CONVECTION ENDING BY 12Z.
ON TUESDAY...A SURFACE TROUGH WILL DEVELOP ALONG THE LEE SIDE OF THE
ROCKIES...INCREASING THE SURFACE PRESSURE GRADIENT OVER WEST CENTRAL
TEXAS SLIGHTLY. SOUTH WINDS WILL INCREASE TO 10 TO 15 MPH. 850MB
TEMPERATURES LOOK SLIGHTLY WARMER THAN WHAT IS BEING EXPERIENCED
THIS AFTERNOON...SO FORECAST REFLECTS SLIGHTLY WARMER TEMPERATURES.
HIGHS AROUND THE AREA WILL GENERALLY BE IN THE LOWER 90S.
LONG TERM...
LONGER TERM PORTION OF THE FORECAST APPEARS FAIRLY QUIET OVERALL.
AS A DEEP LONGWAVE TROUGH DEVELOPS OVER THE ROCKIES...THE
NORTHWEST FLOW ALOFT WILL TRANSITION TO SOUTHWEST FLOW BY LATE WEDNESDAY.
DRYLINE WILL DEVELOP AND SLOSH BACK AND FORTH ACROSS THE PERMIAN
BASIN AND INTO THE WESTERN CONCHO VALLEY AND BIG COUNTRY...BUT CAP
STRENGTH LOOKS AWFULLY STRONG THROUGH THE REST OF THE WEEK. WILL
KEEP THE FORECAST DRY FOR NOW. TEMPERATURES AHEAD OF THE DRYLINE
WILL BE AT OR A LITTLE ABOVE NORMAL...BUT STRONGER SOUTHWEST
DOWNSLOPE FLOW BEHIND THE DRYLINE WILL DRIVE TEMPERATURES TO NEAR
THE 100 DEGREE MARK ACROSS THE WESTERN CONCHO VALLEY AND BIG COUNTRY.
BOTH THE GFS AND THE ECMWF INDICATE A STRONGER SHORTWAVE ROTATING
INTO THE SOUTHERN PLAINS FOR SATURDAY AFTERNOON AND EVENING. GIVEN
THIS ADDED BOOST...A FEW STORMS MAY BE POSSIBLE. STILL...HAVE SOME
QUESTIONS ABOUT THE TIMING AND STRENGTH OF THE WAVE...SO WILL HOLD
OFF FOR NOW AND CONTINUE TO MONITOR.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 64 91 67 95 71 / 20 10 10 0 10
SAN ANGELO 63 92 65 96 70 / 10 10 0 0 10
JUNCTION 61 91 65 92 67 / 10 0 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/04
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
100 PM EDT TUE MAY 22 2012
.SYNOPSIS...
A COLD FRONT SLOWLY PUSHES EAST ACROSS THE AREA THROUGH TONIGHT...AND
THEN TO THE COAST BY LATE WEDNESDAY. SHOWERS AND
THUNDERSTORMS...WITH SOME POTENTIALLY BRINGING HEAVY RAIN...WILL
BE POSSIBLE THROUGH THURSDAY. HIGH PRESSURE AND DRIER WEATHER WILL
ARRIVE LATE IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EDT TUESDAY...
WEAK FRONT EDGING INTO THE FAR WESTERN SECTIONS THIS MORNING LOOKS
TO BE THE MAIN FOCUS FOR DEEPER AFTERNOON CONVECTION ESPCLY ACROSS
THE MOUNTAINS NEAR THE EDGE OF THE CLOUD CANOPY TO THE WEST ATTM.
LATEST MODIFIED MORNING RAOBS SHOW 1500-2K J/KG CAPES PROVIDED
ENOUGH HEATING THIS AFTERNOON UNDER LIGHT STEERING PER A MEAN
FLOW OF 6-10 KTS. THIS SHOULD AGAIN SPELL SLOW MOVING CLUSTERS OF
STORMS ESPCLY MOUNTAINS WITH A FEW OF THESE PERHAPS GOING SEVERE
WITH DOWNBURST POTENTIAL PER DECENT WINDEX VALUES...AND SOME HAIL
GIVEN LOW WET BULB VALUES OFF MORNING SOUNDINGS. HOWEVER WITH SUCH
A MID LEVEL CAP SEEN THIS MORNING MAY TAKE THINGS A LITTLE LONGER
TO DEVELOP WITH BETTER FOCUS LATER ON WEST AS THE UPPER LOW STARTS
TO LIFT NE ALONG THE SRN APPALACHIANS. THUS MAIN CHANGES WERE TO
SLOW DOWN ONSET OF CONVECTION THIS MORNING AND THEN INCREASE POPS
SOME WEST WHERE KEEPING HEAVY RAIN MENTION/WATCH IN PLACE. THIS
SUPPORTED BY EXPANSIVE COVERAGE OFF BOTH THE LATEST HRRR AND LOCAL
WRF MODELS AFTER MIDDAY INTO EARLY THIS EVENING. EXTENT OF TSRA
COVERAGE A BIT MORE IFFY E/SE GIVEN LESS SUPPORT AND MORE OUTFLOW
DRIVEN...BUT EXPECT HIGH CAPES AND EVENTUAL SPILLING OF WESTERN
CONVECTION TO SUPPORT LIKELY POPS THERE. RAISED HIGH TEMPS
SLIGHTLY ALONG THE BLUE RIDGE WHERE SHOULD SEE MORE SUN EARLY OTRW
70S WEST TO LOW 80S EAST APPEAR ON TRACK.
AS OF 615 AM EDT TUESDAY...
UPDATE TO DROP POPS SOME THIS MORNING GIVEN RADAR TRENDS. WILL
SEE INCREASE IN COVERAGE AGAIN OVER THE MTNS BY LATE MORNING.
DECREASED CLOUD COVERAGE EARLY AS WELL ESPECIALLY THE SRN CWA.
PREVIOUS DISCUSSION AT 355 AM...
ECHOES ON RADAR WEAKENING AS EXPECTED BUT NOT SURPRISED THAT
SHOWERS HAVE LINGERED ALL NIGHT...PER HIGHER THETA-E AIR AND
LINGERING BOUNDARIES AND UPPER SUPPORT. TODAY WILL BE ANOTHER
STORMY ONE FOR THE AREA AND EXPECT MORE COVERAGE OF SHOWERS AND
STORMS. GIVEN THE RAINFALL OVER THE MOUNTAINS THAT LAST FEW DAYS
AND LOWER FFG VALUES COMBINED WITH A PATTERN CONDUCIVE TO SLOW
MOVING STORMS AND HIGH PWATS...HAVE WENT AHEAD AN ISSUED A FLASH
FLOOD WATCH FOR AREAS ALONG AND WEST OF THE BLUE RIDGE.
THE FOCUS TODAY WILL BE ACROSS THE MOUNTAINS WHERE BEST UPPER
DIFFLUENCE IS EXPECTED WITH UPPER TROUGH. AT THE SFC...COLD FRONT
WILL BE EDGING EWD TO THE BLUE RIDGE BY EVENING WITH SEVERAL WEAK
LOWS MOVING ALONG IT. WITH EXTENSIVE CLOUD COVER...NOT EXPECT A
WIDESPREAD THREAT FOR SVR BUT WITH MOIST AIRMASS...AND COLDER AIR
ALOFT WITH THE UPPER TROUGH...WOULD NOT BE SURPRISED THAT SOME
STORMS BECOME STRONG TO SEVERE WITH ISOLATED LARGE HAIL/MICROBURST
THREAT. WINDS ALOFT ARE WEAK...SO WOULD HAVE TO BE ENOUGH RAIN
LOADING IN THE STORM TO BRING DAMAGING WINDS.
WILL HAVE HIGHER POPS THIS AFTERNOON WITH CATEGORICAL ACROSS THE
BLUE RIDGE AND WEST. WITH MOIST AIRMASS AND LESS SUN WILL SEE HIGHS
IN BETWEEN THE COOLER MET/WARMER MAV...ALTHOUGH COOLER MET MAY HAVE
A BETTER IDEA. THE LOCAL MOS IN BETWEEN THE TWO SEEMS TO BE A BETTER
CHOICE...GIVEN SOME POTENTIAL FOR SUN. WITH THAT IN MIND...HIGHS
WILL RANGE FROM THE LOWER 80S SOUTHEAST TO THE LOWER 70S IN THE
SOUTHWEST WHERE STORMS ARRIVE/DEVELOP SOONER.
TONIGHT...THE HEAVY RAIN THREAT SHOULD DIMINISH OVERNIGHT AS ONE
AREA OF LIFT PUSHES OUT OF THE AREA. HOWEVER...MODELS SOLUTIONS ARE
CONVERGING TOWARD ANOTHER ORGANIZED AREA OF SHOWERS/STORMS OVER SW
VA AFTER MIDNIGHT...SO IF TRENDS CONTINUE TO SHOW THIS...MAY HAVE TO
EXTEND THE FFA FURTHER IN TIME...AS IT RUNS TIL MIDNIGHT FOR NOW.
LOWS TONIGHT WILL BE MILD AGAIN WITH LOWER TO MID 60 EAST TO MID 50S
WEST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 355 AM EDT TUESDAY...
NOT TOO MUCH CHANGES THIS PERIOD...WITH UPPER TROUGH LINGER OVER THE
AREA...AND SFC FRONT EAST OF THE FORECAST AREA. PATTERN STILL WILL
REMAIN CONDUCIVE FOR SHOWER/STORM DEVELOPMENT ESPECIALLY IN THE
AFTN. MODELS ARE CONVERGING AGAIN ON THE NORTHERN FORECAST AREA TO
SEE MORE RAINFALL...AND KEPT POPS IN THE LIKELY RANGE ACROSS THIS
AREA....WITH HIGH CHANCE SOUTH TO THE NC/VA COUNTIES. HIGHER PWATS
WILL RESIDE OVER THE ERN CWA. AGAIN LOOKING AT MOSTLY CLOUD SKIES
ALL DAY WHICH IS GOING TO LIMIT HEATING AND THE SVR THREAT SHOULD
STAY ISOLATED...WITH HAIL POSSIBLE GIVEN UPPER COOL POOL OVER NC.
EXPECT TO SEE POPS TAPER OFF THE LOW CHANCE TO LESS THAN 20 PERCENT
WEST OF THE BLUE RIDGE AFTER MIDNIGHT WED NIGHT PER UPPER LOW
SHIFTING EAST INTO THE VA PIEDMONT.
THURSDAY LOOKS DRIER...BUT ANOTHER UPPER TROUGH SHIFTS FROM THE
TENNESSEE VALLEY INTO GEORGIA AND UPPER FLOW AND
DIVERGENCE...COMBINED WITH MODEST INSTABILITY SHOULD LEAD TO MORE OF
A SCATTERING OF SHOWERS AND STORMS.
SHOWERS AND STORMS SHOULD START TO WEAKEN THURSDAY NIGHT WITH LOSS
OF HEATING.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 305 PM EDT MONDAY...
THE MEDIUM RANGE MODELS AND ENSEMBLES ARE IN GOOD AGREEMENT
BUILDING A STRONG UPPER RIDGE...FIRST OVER THE OHIO VALLEY...THEN
ELONGATING INTO THE MID-ATLANTIC REGION SUNDAY INTO MONDAY. THIS
WILL RESULT IN TEMPERATURES WELL ABOVE NORMAL AND LESS COVERAGE IN
PRECIPITATION.
ON FRIDAY...THE LINGERING UPPER LEVEL TROF FINALLY GETS PUSHED
NORTHEAST BY A SHORTWAVE MOVING THROUGH THE GREAT LAKES. WITH A
MOIST (GREATER THAN 1.5 PWATS) AND UNSTABLE AIR MASS IN PLACE AND
WEAK LOW LEVEL CONVERGENCE AND THE SFC...WIDELY SCATTERED
THUNDERSTORMS WILL AGAIN BE POSSIBLE.
THE COVERAGE OF SHOWERS AND STORMS SHOULD DIMINISH THROUGH THE
HOLIDAY WEEKEND AS THE UPPER RIDGE BUILDS. HOWEVER...WEAK...BUT
FAIRLY DEEP EAST/SOUTHEAST UPSLOPE LOW LEVEL FLOW MAY BE ABOVE TO
OVERCOME WARMING MID LEVEL TEMPS/RISING HEIGHTS TO INITIATE ISOLATED
TO WIDELY SCT STORMS ALONG THE BLUE RIDGE.
LEARNED TOWARD THE WARMER MEX GUIDANCE FOR TEMPS THROUGH THE LONG
TERM PERIOD...WITH FORECAST HIGHS NEARING RECORDS FOR BLF.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM EDT TUESDAY...
MVFR CIGS ACROSS THE WEST FINALLY STARTING TO MIX OUT WITH
HEATING...OTRW WILL CONTINUE VFR TRENDS OUTSIDE OF CONVECTION
INTO LATE THIS AFTERNOON. CURRENT TSRA FORMING ON THE
RIDGES...MAINLY OUTSIDE OF THE TAF SITES...BUT CLOSE ENOUGH
PROXIMITY TO INCLUDE A VCTS AT KROA AND KLWB TO INIT. ELSW DELAYED
COVERAGE A BIT BUT APPEARS AREAS ALONG/WEST OF THE BLUE RIDGE WILL
START TO FILL IN WITH SHRA/TSRA GIVEN ADDED HEATING/OUTFLOW SO
INCLUDING AT LEAST A VCSH OR VCTS MENTION MOST LOCATIONS FROM MID
AFTERNOON INTO EARLY THIS EVENING. TSRA WILL AGAIN BE SLOW MOVING
WITH POTENTIAL FOR ANY LOCATION TO QUICKLY LOWER TO IFR IN HEAVY
RAINFALL AND LOWER CIGS. WINDS WILL REMAIN MOSTLY LIGHT AND VRBL
BUT COULD GUSTS TO ABOVE 30-40 MPH NEAR ANY OF THE STORMS.
WILL STILL SEE SOME COVERAGE OF CONVECTION HEADING INTO THE
EVENING BUT SHOULD BE LESS...SO ONLY EXTENDED END TIME OUT AN HOUR
OR TWO TO COVER POTENTIAL UNTIL SHORTLY AFTER SUNSET. AGAIN WILL
BE A NIGHT SIMILAR TO LAST NIGHT WHERE CIGS/VSBYS COULD FLUCTUATE
BETWEEN LIFR TO VFR AT TIMES...SO WENT TOWARD MIDDLE ROUTE OF
IFR...MAINLY WITH FOG INSTEAD OF LOWER CIGS. ANY LOCATION THAT
DOES SEE HEAVY RAIN COULD DROP INTO LIFR AFTER MIDNIGHT AND NOT
SEE MUCH IMPROVEMENT UNTIL MID MORNING WEDNESDAY.
WEDNESDAY WILL BE A REPEAT OF TODAY WITH MOST COVERAGE OF STORMS
SHIFTING NORTH OF A LINE FROM BLF-LYH. MAINLY VFR AFTER MORNING
FOG/LOWER CLOUDS EXCEPT IN HEAVIER TSRA.
LOOKING AT THE PATTERN SHIFTING TOWARD THE END OF THE WEEK...AND
UNTIL FRIDAY SHOULD SEE NIGHTTIME THREAT OF LOWER CIGS/FOG AND
DAYTIME THUNDER. BY FRIDAY WILL SEE HIGH PRESSURE WORKING IN TO
BRING VFR WX...AND TEMPERATURES HEAT UP. NIGHLTY FOG IN THE
VALLEYS BCB/LWB A GOOD POSSIBILITY GIVEN THE GROUND SHOULD BE
MOIST...WITH LITTLE WIND.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ007-
009>020-022>024.
NC...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ001-002-
018.
WV...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR WVZ042>045.
&&
$$
SYNOPSIS...JH/PW/WP
NEAR TERM...JH/WP
SHORT TERM...PH/WP
LONG TERM...PH
AVIATION...JH/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1026 AM EDT TUE MAY 22 2012
.SYNOPSIS...
A COLD FRONT SLOWLY PUSHES EAST ACROSS THE AREA THIS AFTERNOON...AND
THEN TO THE COAST BY LATE WEDNESDAY. SHOWERS AND THUNDERSTORMS...WITH
SOME POTENTIALLY BRINGING HEAVY RAIN...WILL BE POSSIBLE THROUGH
THURSDAY. HIGH PRESSURE AND DRIER WEATHER WILL ARRIVE LATE IN THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EDT TUESDAY...
WEAK FRONT EDGING INTO THE FAR WESTERN SECTIONS THIS MORNING LOOKS
TO BE THE MAIN FOCUS FOR DEEPER AFTERNOON CONVECTION ESPCLY ACROSS
THE MOUNTAINS NEAR THE EDGE OF THE CLOUD CANOPY TO THE WEST ATTM.
LATEST MODIFIED MORNING RAOBS SHOW 1500-2K J/KG CAPES PROVIDED
ENOUGH HEATING THIS AFTERNOON UNDER LIGHT STEERING PER A MEAN
FLOW OF 6-10 KTS. THIS SHOULD AGAIN SPELL SLOW MOVING CLUSTERS OF
STORMS ESPCLY MOUNTAINS WITH A FEW OF THESE PERHAPS GOING SEVERE
WITH DOWNBURST POTENTIAL PER DECENT WINDEX VALUES...AND SOME HAIL
GIVEN LOW WET BULB VALUES OFF MORNING SOUNDINGS. HOWEVER WITH SUCH
A MID LEVEL CAP SEEN THIS MORNING MAY TAKE THINGS A LITTLE LONGER
TO DEVELOP WITH BETTER FOCUS LATER ON WEST AS THE UPPER LOW STARTS
TO LIFT NE ALONG THE SRN APPALACHIANS. THUS MAIN CHANGES WERE TO
SLOW DOWN ONSET OF CONVECTION THIS MORNING AND THEN INCREASE POPS
SOME WEST WHERE KEEPING HEAVY RAIN MENTION/WATCH IN PLACE. THIS
SUPPORTED BY EXPANSIVE COVERAGE OFF BOTH THE LATEST HRRR AND LOCAL
WRF MODELS AFTER MIDDAY INTO EARLY THIS EVENING. EXTENT OF TSRA
COVERAGE A BIT MORE IFFY E/SE GIVEN LESS SUPPORT AND MORE OUTFLOW
DRIVEN...BUT EXPECT HIGH CAPES AND EVENTUAL SPILLING OF WESTERN
CONVECTION TO SUPPORT LIKELY POPS THERE. RAISED HIGH TEMPS
SLIGHTLY ALONG THE BLUE RIDGE WHERE SHOULD SEE MORE SUN EARLY OTRW
70S WEST TO LOW 80S EAST APPEAR ON TRACK.
AS OF 615 AM EDT TUESDAY...
UPDATE TO DROP POPS SOME THIS MORNING GIVEN RADAR TRENDS. WILL
SEE INCREASE IN COVERAGE AGAIN OVER THE MTNS BY LATE MORNING.
DECREASED CLOUD COVERAGE EARLY AS WELL ESPECIALLY THE SRN CWA.
PREVIOUS DISCUSSION AT 355 AM...
ECHOES ON RADAR WEAKENING AS EXPECTED BUT NOT SURPRISED THAT
SHOWERS HAVE LINGERED ALL NIGHT...PER HIGHER THETA-E AIR AND
LINGERING BOUNDARIES AND UPPER SUPPORT. TODAY WILL BE ANOTHER
STORMY ONE FOR THE AREA AND EXPECT MORE COVERAGE OF SHOWERS AND
STORMS. GIVEN THE RAINFALL OVER THE MOUNTAINS THAT LAST FEW DAYS
AND LOWER FFG VALUES COMBINED WITH A PATTERN CONDUCIVE TO SLOW
MOVING STORMS AND HIGH PWATS...HAVE WENT AHEAD AN ISSUED A FLASH
FLOOD WATCH FOR AREAS ALONG AND WEST OF THE BLUE RIDGE.
THE FOCUS TODAY WILL BE ACROSS THE MOUNTAINS WHERE BEST UPPER
DIFFLUENCE IS EXPECTED WITH UPPER TROUGH. AT THE SFC...COLD FRONT
WILL BE EDGING EWD TO THE BLUE RIDGE BY EVENING WITH SEVERAL WEAK
LOWS MOVING ALONG IT. WITH EXTENSIVE CLOUD COVER...NOT EXPECT A
WIDESPREAD THREAT FOR SVR BUT WITH MOIST AIRMASS...AND COLDER AIR
ALOFT WITH THE UPPER TROUGH...WOULD NOT BE SURPRISED THAT SOME
STORMS BECOME STRONG TO SEVERE WITH ISOLATED LARGE HAIL/MICROBURST
THREAT. WINDS ALOFT ARE WEAK...SO WOULD HAVE TO BE ENOUGH RAIN
LOADING IN THE STORM TO BRING DAMAGING WINDS.
WILL HAVE HIGHER POPS THIS AFTERNOON WITH CATEGORICAL ACROSS THE
BLUE RIDGE AND WEST. WITH MOIST AIRMASS AND LESS SUN WILL SEE HIGHS
IN BETWEEN THE COOLER MET/WARMER MAV...ALTHOUGH COOLER MET MAY HAVE
A BETTER IDEA. THE LOCAL MOS IN BETWEEN THE TWO SEEMS TO BE A BETTER
CHOICE...GIVEN SOME POTENTIAL FOR SUN. WITH THAT IN MIND...HIGHS
WILL RANGE FROM THE LOWER 80S SOUTHEAST TO THE LOWER 70S IN THE
SOUTHWEST WHERE STORMS ARRIVE/DEVELOP SOONER.
TONIGHT...THE HEAVY RAIN THREAT SHOULD DIMINISH OVERNIGHT AS ONE
AREA OF LIFT PUSHES OUT OF THE AREA. HOWEVER...MODELS SOLUTIONS ARE
CONVERGING TOWARD ANOTHER ORGANIZED AREA OF SHOWERS/STORMS OVER SW
VA AFTER MIDNIGHT...SO IF TRENDS CONTINUE TO SHOW THIS...MAY HAVE TO
EXTEND THE FFA FURTHER IN TIME...AS IT RUNS TIL MIDNIGHT FOR NOW.
LOWS TONIGHT WILL BE MILD AGAIN WITH LOWER TO MID 60 EAST TO MID 50S
WEST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 355 AM EDT TUESDAY...
NOT TOO MUCH CHANGES THIS PERIOD...WITH UPPER TROUGH LINGER OVER THE
AREA...AND SFC FRONT EAST OF THE FORECAST AREA. PATTERN STILL WILL
REMAIN CONDUCIVE FOR SHOWER/STORM DEVELOPMENT ESPECIALLY IN THE
AFTN. MODELS ARE CONVERGING AGAIN ON THE NORTHERN FORECAST AREA TO
SEE MORE RAINFALL...AND KEPT POPS IN THE LIKELY RANGE ACROSS THIS
AREA....WITH HIGH CHANCE SOUTH TO THE NC/VA COUNTIES. HIGHER PWATS
WILL RESIDE OVER THE ERN CWA. AGAIN LOOKING AT MOSTLY CLOUD SKIES
ALL DAY WHICH IS GOING TO LIMIT HEATING AND THE SVR THREAT SHOULD
STAY ISOLATED...WITH HAIL POSSIBLE GIVEN UPPER COOL POOL OVER NC.
EXPECT TO SEE POPS TAPER OFF THE LOW CHANCE TO LESS THAN 20 PERCENT
WEST OF THE BLUE RIDGE AFTER MIDNIGHT WED NIGHT PER UPPER LOW
SHIFTING EAST INTO THE VA PIEDMONT.
THURSDAY LOOKS DRIER...BUT ANOTHER UPPER TROUGH SHIFTS FROM THE
TENNESSEE VALLEY INTO GEORGIA AND UPPER FLOW AND
DIVERGENCE...COMBINED WITH MODEST INSTABILITY SHOULD LEAD TO MORE OF
A SCATTERING OF SHOWERS AND STORMS.
SHOWERS AND STORMS SHOULD START TO WEAKEN THURSDAY NIGHT WITH LOSS
OF HEATING.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 305 PM EDT MONDAY...
THE MEDIUM RANGE MODELS AND ENSEMBLES ARE IN GOOD AGREEMENT
BUILDING A STRONG UPPER RIDGE...FIRST OVER THE OHIO VALLEY...THEN
ELONGATING INTO THE MID-ATLANTIC REGION SUNDAY INTO MONDAY. THIS
WILL RESULT IN TEMPERATURES WELL ABOVE NORMAL AND LESS COVERAGE IN
PRECIPITATION.
ON FRIDAY...THE LINGERING UPPER LEVEL TROF FINALLY GETS PUSHED
NORTHEAST BY A SHORTWAVE MOVING THROUGH THE GREAT LAKES. WITH A
MOIST (GREATER THAN 1.5 PWATS) AND UNSTABLE AIR MASS IN PLACE AND
WEAK LOW LEVEL CONVERGENCE AND THE SFC...WIDELY SCATTERED
THUNDERSTORMS WILL AGAIN BE POSSIBLE.
THE COVERAGE OF SHOWERS AND STORMS SHOULD DIMINISH THROUGH THE
HOLIDAY WEEKEND AS THE UPPER RIDGE BUILDS. HOWEVER...WEAK...BUT
FAIRLY DEEP EAST/SOUTHEAST UPSLOPE LOW LEVEL FLOW MAY BE ABOVE TO
OVERCOME WARMING MID LEVEL TEMPS/RISING HEIGHTS TO INITIATE ISOLATED
TO WIDELY SCT STORMS ALONG THE BLUE RIDGE.
LEARNED TOWARD THE WARMER MEX GUIDANCE FOR TEMPS THROUGH THE LONG
TERM PERIOD...WITH FORECAST HIGHS NEARING RECORDS FOR BLF.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS OF 715 AM EDT TUESDAY...
ANY FOG/LOWER CIGS WILL BE LIFTING SOON AND SHOULD SEE MAINLY
VFR CONDITIONS TODAY OUTSIDE OF STORMS. THE STORMS SHOULD FORM
AGAIN BY MIDDAY OVER THE MOUNTAINS WITH SLOW MOVEMENT...THEN
STORMS WILL BE FORMING ALONG/EAST OF THE BLUE RIDGE TOWARD 18Z-21Z.
THE BEST COVERAGE TODAY SHOULD BE ALONG/WEST OF THE BLUE
RIDGE...AND WILL SEE HEAVY RAINS FROM THESE STORMS. GIVEN THE
NATURE OF THIS PATTERN...KEPT TAFS LOW END VFR.
WILL STILL SEE SOME COVERAGE OF CONVECTION HEADING INTO THE
EVENING BUT SHOULD BE LESS...SO TOOK IT ALL OUT OF TAFS. AGAIN
WILL BE A NIGHT SIMILAR TO THIS MORNING WHERE CIGS/VSBYS COULD
FLUCTUATE BETWEEN LIFR TO VFR AT TIMES...SO WENT TOWARD MIDDLE
ROUTE OF IFR...MAINLY WITH FOG INSTEAD OF LOWER CIGS.
WEDNESDAY WILL BE A REPEAT OF TODAY WITH MOST COVERAGE OF STORMS
SHIFTING NORTH OF A LINE FROM BLF-LYH. MAINLY VFR AFTER MORNING
FOG/LOWER CLOUDS EXCEPT IN HEAVIER TSRA.
LOOKING AT THE PATTERN SHIFTING TOWARD THE END OF THE WEEK...AND
UNTIL FRIDAY SHOULD SEE NIGHTTIME THREAT OF LOWER CIGS/FOG AND
DAYTIME THUNDER. BY FRIDAY WILL SEE HIGH PRESSURE WORKING IN TO
BRING VFR WX...AND TEMPERATURES HEAT UP. NIGHLTY FOG IN THE
VALLEYS BCB/LWB A GOOD POSSIBILITY GIVEN THE GROUND SHOULD BE
MOIST...WITH LITTLE WIND.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-009>020-
022>024.
NC...FLASH FLOOD WATCH THROUGH THIS EVENING FOR NCZ001-002-018.
WV...FLASH FLOOD WATCH THROUGH THIS EVENING FOR WVZ042>045.
&&
$$
SYNOPSIS...PW/WP
NEAR TERM...JH/WP
SHORT TERM...PH/WP
LONG TERM...PH
AVIATION...WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
534 PM CDT TUE MAY 22 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY.
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM THE SOUTHERN GREAT PLAINS AND ACROSS THE
CENTRAL GREAT LAKES TO HUDSON BAY. A WARM FRONT HAS BEEN
DEVELOPING TODAY OVER THE FAR NORTHERN PLAINS AND OVER WESTERN
LAKE SUPERIOR TO THE UPPER PENINSULA. WARM/MOIST ADVECTION NORTH
OF THE BOUNDARY IS CONTRIBUTING TO SCT LIGHT SHOWERS AND ISOLATED
THUNDERSTORMS FROM NORTHERN MINNESOTA TO THE WESTERN UPPER
PENINSULA. SOME RETURNS ARE GRAZING THE U.P. BORDER THIS
AFTERNOON...BUT NO CONFIRMATION OF THESE RETURNS REACHING THE
GROUND AT IRONWOOD OR LAND O LAKES. THE AIRMASS IS PRETTY DRY IN
THIS AREA WITH DEWPOINTS AT LAND O LAKES IN THE LOWER 30S. AS LOW
PRESSURE OVER WESTERN NORTH DAKOTA MOVES NORTHEAST...A COLD FRONT
WILL MOVE TO THE UPPER MISSISSIPPI VALLEY TOMORROW. WITHOUT MUCH
IMPACT YET...CLOUDS AND TEMPS WILL BE THE MAIN FORECAST CONCERNS.
TONIGHT...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES TO START THE
EVENING WILL SHIFT TO THE EASTERN GREAT LAKES OVERNIGHT. LOW
PRESSURE WILL MOVE NORTHEAST OVER THE PLAINS TONIGHT...BUT ITS
WARM FRONT WILL REMAIN RELATIVELY STATIONARY OVER THE SOUTH
SHORELINE OF LAKE SUPERIOR. WARM/MOIST ADVECTION THAT IS OCCURRING
OVER THE ARROWHEAD OF MINNESOTA AND THE UPPER PENINSULA WILL BE
LIFTING OFF TO THE NORTHEAST GRADUALLY AS HEIGHTS BUILD
ALOFT...EVEN THOUGH CORFIDI VECTORS TRACK THE INDIVIDUAL SHOWERS
OFF TO THE SOUTHEAST. THINK THERE IS POTENTIAL FOR THIS SHOWER
ACTIVITY TO GRAZE THE U.P.-WISCONSIN BORDER THROUGH 00Z.
HOWEVER...LOW LEVELS ARE VERY DRY...SO WILL LEAVE IT AS A CHANCE
OF SPRINKLES. RECENT RADAR TRENDS ALREADY SHOW THE BACK EDGE OF
THE PRECIP LIFTING NE OVER THE ARROWHEAD...SO AM COUNTING ON THIS
TREND KEEPING THE BORDER DRY AFTER 00Z. MID AND UPPER CLOUDS WILL
BE LIFTING OFF TO THE NE AS WELL SO SHOULD SEE DECREASING CLOUDS
THROUGH THE NIGHT OVER THE NORTH. THE PRESSURE GRADIENT WILL BE
TIGHTENING TONIGHT...WHICH WILL KEEP LOWS WARMER THAN LAST NIGHT.
WILL GO WITH MID TO UPPER 40S FOR LOWS.
WEDNESDAY...UPSTREAM COLD FRONT WILL MOVE INTO THE NORTHERN
MISSISSIPPI VALLEY DURING THE AFTERNOON. WITH THE AREA FIRMLY IN
THE WARM SECTOR...WILL HAVE MID AND UPPER CLOUDS NORTH AND WEST OF
THE REGION...BUT SHOULD SEE MOSTLY CLEAR TO PARTLY CLOUDY SKIES
FOR THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AHEAD OF THE
FRONT...AND SOUTH WINDS WILL TURN GUSTY WITH DAYTIME HEATING AND
MIXING. SOME GUSTS COULD REACH 30 OR MAYBE EVEN 35 MPH. HIGHS
TOMORROW IN THE MID 70S TO LOW 80S.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY. ONE OF THE
FORECAST CHALLENGES FOR THIS PERIOD IS TRYING TO LASSO IN THE
LOCATIONS OF THE FRONT FOR THE MEMORIAL DAY WEEKEND. ANOTHER ISSUE
IS TIMING AND STRENGTH OF A SHORT WAVE TROUGH FOR LATER THURSDAY
AND ESPECIALLY THURSDAY NIGHT.
LITTLE CHANGE FROM THE GOING FORECAST FROM 24 HOURS AGO FROM
WEDNESDAY NIGHT INTO THURSDAY AS A SURFACE HIGH PRESSURE WITH
UPPER RIDGE DRIFTING OVER THE AREA WILL CONTINUE TO PROVIDE QUIET
WEATHER TO THE AREA. MODELS CONTINUE TO CONFINE CONVECTION OVER
THE NORTHERN PLAINS WITH THE BROAD UPPER TROUGH. PWATS GRADUALLY
INCREASE TO 1.75 ALONG THE FRONT OVER THE NORTHERN PLAINS. UNTIL
THIS UPPER RIDGE IS NUDGED FAR ENOUGH EAST...WILL CONTINUE TO
CONFINE ANY SMALL PCPN MENTION AND CLOUDS WEST OF A RHI TO AUW
LINE.
WILL THEN FOCUS ON HIGHER POPS FOR THE THURSDAY AFTERNOON INTO
THURSDAY NIGHT PERIOD AS A SHORT WAVE SLIDES OVER THE STATE. A
SURFACE LOW AND UPPER JET COUPLET PROGGED TO AFFECT THE NORTH HALF
OF THE STATE DURING THIS PERIOD PROVIDES SOME POTENTIAL OF STRONG
TO SEVERE STORMS. PROGS ARE A BIT MORE PROGRESSIVE WITH THE
FRONTAL PASSAGE LATE THURSDAY NIGHT. USING THE H8 FRONT...THE
FRONT IS DRIVEN SOUTH OF THE AREA FRIDAY INTO FRIDAY NIGHT FOR A
DIMINISHED PERIOD OF CONVECTION. PROGS IN GOOD AGREEMENT WITH H8
WARM FRONT LIFTING BACK NORTH AGAIN ON SATURDAY SO INCREASED
CONVECTION INCLUDING THUNDER FROM SOUTH TO NORTH DURING THE DAY.
PROGS CONTINUE TO LIFT THE FRONT NORTH TO GRADUALLY DIMINISH
CONVECTION OVER CENTRAL AND EAST CENTRAL WISCONSIN BUT WILL
CONFINE BEST PCPN CHANCES ACROSS THE NORTH SUNDAY AND PERHAPS INTO
MONDAY CLOSER TO THE WARM FRONT. AREAS TO THE SOUTH LIKELY TO BE
CAPPED IN A VERY WARM HUMID AIR MASS AS UPPER HEIGHTS BUILD.
ANOTHER FRONT IS PROGGED TO SLIDE OVER MONDAY INTO MONDAY NIGHT
FOR ANOTHER SHOT OF CONVECTION. PWATS INCREASE TO 1.70 INCHES
ALONG THE FRONT...HOWEVER AT THIS TIME IT APPEARS THE FRONTS ARE A
LITTLE TOO PROGRESSIVE FOR HEAVY RAINS TO CONCENTRATE IN ANY ONE
LOCATION WITH THE EXCEPTION OF THE FAR NORTH NEAR THE WARM FRONT.
&&
.AVIATION...FOR 00Z TAF ISSUANCE. VFR CONDITIONS EXPECTED TNGT AND
WED AS SFC RIDGE SLIDES AWAY TO THE SE AND FRONTAL SYSTEM STARTS
TO ADVANCE E FM THE PLAINS. MAIN FCST ISSUE IS LLWS POTENTIAL
TNGT. RAP CONSIDERABLY STRONGER WITH WINDS 1-2K FT IN C/N-C WI THAN
THE NAM...AND THE NAM IS NORMALLY ON THE HIGH END OF THE GUID WITH
LOW-LEVEL WINDS. CONSIDERABLE SPREAD AMONG SREF MEMBERS AS
WELL. OVERALL...SREF SEEMS TO LEND ENOUGH SUPPORT TO INCLUDE
LLWS IN THE WRN TAF SITES...BUT AS LEVELS BLO THOSE SHOWN ON RAP
FCST SOUNDINGS.
SKOWRONSKI
&&
.MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED LATE
WEDNESDAY AFTERNOON INTO THURSDAY NIGHT. INCREASING SOUTH WINDS
ARE EXPECTED ON WEDNESDAY...THEN STRONG SOUTH WINDS ARE EXPECTED
ON THURSDAY. A FEW GUSTS COULD APPROACH GALE FORCE NEAR THE
SHORELINE THURSDAY AFTERNOON. WINDS AND WAVES WILL GRADUALLY
SUBSIDE THURSDAY NIGHT.
FOR THE UPCOMING MEMORIAL DAY WEEKEND...IT WILL BE UNSETTLED AS
THERE WILL BE CHANCES FOR THUNDERSTORMS EACH DAY. A WARM FRONT IS
EXPECTED TO SLOWLY PUSH NORTHWARD INTO THE AREA OVER THE WEEKEND.
THERE IS A LOT OF UNCERTAINTY ON HOW FAR NORTH THE WARM FRONT WILL
MAKE IT INTO NORTHEAST WISCONSIN AND WHERE THE BEST CHANCES FOR
THUNDERSTORMS WOULD OCCUR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
303 PM CDT TUE MAY 22 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY
303 PM CDT TUE MAY 22 2012
MAIN FORECAST CONCERNS ARE WHEN PRECIPITATION CHANCES MOVE INTO THE
AREA AND SEVERE WEATHER POTENTIAL FOR THURSDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER SOUTHWEST CANADA AND THE NORTHERN ROCKIES...
WITH RIDGING BUILDING DOWNSTREAM OVER THE UPPER MISSISSIPPI RIVER
VALLEY REGION. A SHORTWAVE EJECTING OUT OF THE TROUGHING AND
DOWNSLOPING UPPER FLOW OFF THE ROCKIES HAS LED TO LOW PRESSURE
DEVELOPMENT OVER THE DAKOTAS. INCREASING SOUTHERLY FLOW DOWNSTREAM
OF THIS SURFACE LOW ON THE ORDER OF 20-40KT 850MB WINDS PER PROFILER
DATA IS SPREADING WARMER AIR NORTHWARD. MODIFYING THROUGH ADVECTION
AND DAYTIME HEATING PROCESSES FROM 12Z RAOBS...THE RAP SUGGESTS
850MB TEMPS HAVE RISEN TO 10-14C OVER THE FORECAST AREA. WITH PLENTY
OF SUN AND THE INCREASING WINDS...SURFACE TEMPERATURES HAVE CLIMBED
INTO THE 70S TO LOW 80S. FARTHER WEST...THE 850MB TEMPS INCREASE TO
18-25C OR HIGHER OVER MUCH OF THE PLAINS. MOISTURE IS ALSO
RETURNING...MORE OVER THE PLAINS...WHERE SURFACE DEWPOINTS ARE
MOSTLY IN THE 50S.
TONIGHT AND WEDNESDAY...TROUGHING OVER THE NORTHERN ROCKIES IS
FORECAST TO DEEPEN ACROSS THE WESTERN U.S....RESULTING IN
STRENGTHENING RIDGING DOWNSTREAM INTO THE GREAT LAKES. A COUPLE OF
SHORTWAVES EJECTING OUT OF THIS TROUGHING WILL HELP LIFT THE LOW IN
THE DAKOTAS INTO FAR NORTHWEST ONTARIO...DRAGGING A COLD FRONT INTO
WESTERN MINNESOTA BY 00Z. INCREASING SOUTH TO SOUTHWEST FLOW ALOFT
AHEAD OF THE FRONT WILL HELP BRING WARMER AIR INTO THE FORECAST AREA
WITH 850MB TEMPS CLIMBING TO AT LEAST 16-18C BY 18Z WEDNESDAY. WE
SHOULD ALSO SEE AN INCREASE IN ALTOSTRATUS AND CIRROSTRATUS...
ALREADY EVIDENT OVER EASTERN MONTANA AND WYOMING. THESE CLOUDS MAY
TEMPER HIGHS SOMEWHAT...BUT READINGS SHOULD EASILY REACH INTO THE
80S GIVEN THE STRENGTH OF THE WARM ADVECTION/WINDS AND SUN. LOWS
TONIGHT ALSO EXPECTED TO BE WARMER WITH THE INCREASING WINDS...
ESPECIALLY ACROSS SOUTHEAST MINNESOTA. REGARDING PRECIPITATION
CHANCES...ANY CONVECTION SHOULD BE STRONGLY TIED TO THE FRONT. AHEAD
OF THE FRONT...MODELS SUGGEST QUITE A BIT OF CIN...EVEN WITH THEIR
HIGHER SURFACE DEWPOINTS LIKE THE NAM SUGGESTS. THERE IS ALSO MIX
DOWN POTENTIAL OF THE DEWPOINTS WITH PLENTIFUL DRY AIR BELOW 700MB.
THEREFORE...THINKING THE ENTIRE FORECAST AREA SHOULD BE DRY THROUGH
WEDNESDAY. LAST ITEM OF NOTE IS WINDS COULD GET CLOSE TO ADVISORY
CRITERIA IN SOUTHEAST MN LATE IN THE MORNING INTO MID AFTERNOON...
JUST BASED ON THE SPEEDS THEMSELVES. SOMETHING TO WATCH.
WEDNESDAY NIGHT AND THURSDAY...AT THE BASE OF THE DEEPENING WESTERN
TROUGH...A NEW SURFACE LOW SHOULD HAVE DEVELOPED OVER FAR SOUTHEAST
COLORADO BY 00Z THURSDAY. THIS SURFACE LOW IS EXPECTED TO LIFT
NORTHEAST...ALONG THE COLD FRONT THAT MOVED INTO WESTERN MINNESOTA
LATE WEDNESDAY...DUE TO ANOTHER COLLECTION OF SHORTWAVES EJECTING
OUT OF THE WESTERN TROUGH. THEREFORE...THE FRONT WEDNESDAY NIGHT IS
LIKELY TO NOT MAKE MUCH IF ANY PROGRESS EASTWARD. IN FACT...WE NEED
TO WAIT UNTIL THE LOW MOVES NORTH OF THE AREA TO DRIVE THE COLD
FRONT EASTWARD. THIS DRIVE EASTWARD TOO WILL BE ENHANCED BY A FAIRLY
POTENT SHORTWAVE COMING UP INTO MINNESOTA. FOR WEDNESDAY NIGHT...
AGAIN CONVECTION SHOULD REMAIN TIED AROUND THE COLD FRONT IN
MINNESOTA. VARIOUS THINGS GOING FOR CONVECTION INCLUDE A RIGHT
ENTRANCE REGION OF A JET LIFTING OUT OF THE DAKOTAS...INCREASING LOW
TO MID-LEVEL FRONTOGENESIS ON THE COLD FRONT...AND A PLUME OF
500-1000 J/KG OF MUCAPE BEING TRANSPORTED INTO THE FRONTOGENESIS
ZONE BY A STRENGTHENING LOW LEVEL JET. AS IT STANDS RIGHT NOW...MOST
MODELS SUGGEST THE FRONT AND BULK OF CONVECTION WILL END UP WEST OF
THE FORECAST AREA. HAVE MAINTAINED SOME CHANCES OVER THE NORTHWEST
ENDS...THOUGH...AS CONVECTIVE OUTFLOWS MAY TRY TO PUSH THE FRONT
EASTWARD. THURSDAY IS DEFINITELY MORE CONCERNING AS THE POTENT
SHORTWAVE APPROACHES IN THE AFTERNOON. SOME SLIGHT TIMING
DIFFERENCES EXIST ON THE COLD FRONTAL PASSAGE AND APPROACH OF THE
SHORTWAVE...BUT THERE IS GOOD AGREEMENT THAT THE DYNAMICAL AND
THERMODYNAMICAL FORCING WILL LIKELY LEAD TO A SQUALL LINE ALONG THE
FRONT EARLY TO MID AFTERNOON...ALONG WITH POST-FRONTAL
PRECIPITATION. THIS PRECIPITATION THEN PUSHES EAST INTO THE EVENING.
RAISED PRECIPITATION CHANCES TO 50-70 FOR THE AFTERNOON. PLENTIFUL
0-6 KM AND 0-3KM SHEAR AND MLCAPE OF 500-1000 J/KG SHOULD BE ENOUGH
TO PRODUCE SOME SEVERE WEATHER...WITH DAMAGING WINDS MAIN HAZARD.
TEMPERATURES LIKELY TO STAY WARM WEDNESDAY NIGHT AND THURSDAY DUE TO
BREEZY WINDS...WITH A POSSIBLE FALL IN TEMPERATURES IN THE AFTERNOON
AS THE FRONT/PRECIPITATION MOVE THROUGH. WINDS COULD GET CLOSE TO
ADVISORY CRITERIA ON THURSDAY.
THURSDAY NIGHT AND FRIDAY...AFTER THE SQUALL LINE AND COLD FRONT
MOVE THROUGH IN THE EVENING...STRONG SUBSIDENCE IS INDICATED TO MOVE
INTO THE FORECAST AREA. RAISED PRECIPITATION CHANCES EAST OF THE
MISSISSIPPI RIVER TO 50-70 TO HANDLE THE SQUALL LINE. CONDITIONS
SHOULD THEN DRY OUT AFTER MIDNIGHT THANKS TO THE SUBSIDENCE...
PRODUCED MOSTLY BY THAT POTENT SHORTWAVE WHICH LIFTS INTO UPPER
MICHIGAN. THE COLD FRONT LOOKS TO STALL OVER NORTHERN MISSOURI
FRIDAY MORNING. NEW DEEPER TROUGHING THEN FORMS IN THE WESTERN
U.S....CAUSING RIDGING TO RE-BUILD DOWNSTREAM INTO THE
MID-MISSISSIPPI VALLEY. DEPENDING ON THIS TIMING OF THE RIDGING
BUILDING UP...THE FRONT MAY START MOVING BACK NORTH IN THE
AFTERNOON...AS INDICATED IN THE 22.12Z NAM/GEM. MOISTURE TRANSPORT
OVER THIS FRONT COULD LEAD TO A FEW SHOWERS AND THUNDERSTORMS OVER
NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN...THOUGH DEFINITELY
BETTER CHANCES WOULD BE OVER SOUTHERN IOWA CLOSER TO THE FRONT.
COOLER AIR ADVECTING IN BEHIND THE FRONT SHOULD HELP SEND
TEMPERATURES BACK DOWN TO SEASONABLE LEVELS.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
303 PM CDT TUE MAY 22 2012
MODELS AND GFS ENSEMBLES ARE INCREASINGLY BECOMING IN GOOD AGREEMENT
FOR THE WEEKEND...INDICATING TROUGHING TO PERSIST OVER THE WESTERN
U.S. WHILE STRONG SUBTROPICAL RIDGING BUILDS OVER THE EASTERN TWO
THIRDS OF THE COUNTRY. WITH THIS BUILDING RIDGING...THE WARM FRONT
ON FRIDAY SITUATED EITHER OVER SOUTHERN IOWA OR NORTHERN MISSOURI
WILL GRADUALLY LIFT NORTH ACROSS THE FORECAST AREA. THE SPEED OF
THIS MAY BE MODULATED BY PERIODS OF CONVECTION FORMING ON THE WARM
FRONTAL BOUNDARY...IN RESPONSE TO FRONTOGENESIS AND ESPECIALLY
INCREASING LOW LEVEL JET/MOISTURE TRANSPORT AT NIGHT. BEST TIME
PERIOD FOR CONVECTION ACROSS THE AREA WOULD PROBABLY BE FRIDAY NIGHT
INTO SATURDAY MORNING. SATURDAY NIGHT INTO SUNDAY MORNING COULD
OCCUR TOO OVER FAR NORTHERN PORTIONS OF THE AREA...DEPENDING ON HOW
FAR NORTH THE WARM FRONT REACHES. EITHER ROUND OF CONVECTION COULD
BE SEVERE...GIVEN 1-6 KM SHEAR VALUES OF 40KT OR MORE AND LIKELY
PLENTY OF INSTABILITY BEING ADVECTED OVER THE FRONTAL ZONE. ONCE THE
WARM FRONT PASSES...850MB TEMPS JUMP TO 20C OR HIGHER. SUNDAY LOOKS
TO BE THE WARM DAY WITH TEMPERATURES LIKELY WELL INTO THE
80S...PERHAPS EVEN 90S.
THINGS GET A LITTLE MORE MURKY FOR EARLY NEXT WEEK...IN PARTICULAR
WITH THE HANDLING OF THE WESTERN TROUGH. THE 22.00Z/22.12Z ECMWF/GEM
AND SOME OF THE 22.12Z GFS ENSEMBLES SUGGEST THE WESTERN TROUGH WILL
BE SLOWER TO EJECT NORTHEASTWARD THAN THE 22.12Z GFS AND THE REST OF
ITS ENSEMBLES. THIS SEEMS REASONABLE GIVEN THE STRENGTH OF THE
RIDGING AHEAD OF THE TROUGH. THEREFORE...LIKELY THE COLD FRONT
ASSOCIATED WITH THE TROUGH WILL BE SLOWER TO MOVE THROUGH THE
FORECAST AREA. THIS RESULTS IN A WARMER DAY ON MONDAY THAN WHAT
THE GFS WOULD SUGGEST. TUESDAY WOULD BE COOLER AFTER THE FRONTAL
PASSAGE. DID MAINTAIN THE CONSENSUS APPROACH FOR PRECIPITATION
CHANCES MONDAY THROUGH TUESDAY...GIVEN THE DIFFERENCES.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
1233 PM CDT TUE MAY 22 2012
MAIN CONCERN THROUGH THE PERIOD WILL BE INCREASING SOUTH
WINDS...ESPECIALLY DURING THE DAY WEDNESDAY AS A LOW AND COLD
FRONT APPROACH FROM THE NORTHERN PLAINS. SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE SEEN ALONG AND AHEAD OF THIS APPROACHING
FRONT...BUT ARE EXPECTED TO REMAIN WEST OF THE FORECAST AREA. PLAN
ON SOME MID/HIGH LEVEL CLOUD DEBRIS FROM THIS SCATTERED CONVECTION
TO DRIFT OVER THE KRST/KLSE TAF SITES...OTHERWISE VFR CONDITIONS
WILL PREVAIL TONIGHT THROUGH MIDDAY WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
303 PM CDT TUE MAY 22 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
243 PM CDT TUE MAY 22 2012
.SHORT TERM...TONIGHT AND WEDNESDAY.
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM THE SOUTHERN GREAT PLAINS AND ACROSS THE
CENTRAL GREAT LAKES TO HUDSON BAY. A WARM FRONT HAS BEEN DEVELOPING
TODAY OVER THE FAR NORTHERN PLAINS AND OVER WESTERN LAKE SUPERIOR TO
THE UPPER PENINSULA. WARM/MOIST ADVECTION NORTH OF THE BOUNDARY IS
CONTRIBUTING TO SCT LIGHT SHOWERS AND ISOLATED THUNDERSTORMS FROM
NORTHERN MINNESOTA TO THE WESTERN UPPER PENINSULA. SOME RETURNS ARE
GRAZING THE U.P. BORDER THIS AFTERNOON...BUT NO CONFIRMATION OF
THESE RETURNS REACHING THE GROUND AT IRONWOOD OR LAND O LAKES. THE
AIRMASS IS PRETTY DRY IN THIS AREA WITH DEWPOINTS AT LAND O LAKES IN
THE LOWER 30S. AS LOW PRESSURE OVER WESTERN NORTH DAKOTA MOVES
NORTHEAST...A COLD FRONT WILL MOVE TO THE UPPER MISSISSIPPI VALLEY
TOMORROW. WITHOUT MUCH IMPACT YET...CLOUDS AND TEMPS WILL BE THE
MAIN FORECAST CONCERNS.
TONIGHT...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES TO START THE
EVENING WILL SHIFT TO THE EASTERN GREAT LAKES OVERNIGHT. LOW
PRESSURE WILL MOVE NORTHEAST OVER THE PLAINS TONIGHT...BUT ITS WARM
FRONT WILL REMAIN RELATIVELY STATIONARY OVER THE SOUTH SHORELINE OF
LAKE SUPERIOR. WARM/MOIST ADVECTION THAT IS OCCURRING OVER THE
ARROWHEAD OF MINNESOTA AND THE UPPER PENINSULA WILL BE LIFTING OFF
TO THE NORTHEAST GRADUALLY AS HEIGHTS BUILD ALOFT...EVEN THOUGH CORFIDI
VECTORS TRACK THE INDIVIDUAL SHOWERS OFF TO THE SOUTHEAST. THINK
THERE IS POTENTIAL FOR THIS SHOWER ACTIVITY TO GRAZE THE
U.P.-WISCONSIN BORDER THROUGH 00Z. HOWEVER...LOW LEVELS ARE VERY
DRY...SO WILL LEAVE IT AS A CHANCE OF SPRINKLES. RECENT RADAR
TRENDS ALREADY SHOW THE BACK EDGE OF THE PRECIP LIFTING NE OVER THE
ARROWHEAD...SO AM COUNTING ON THIS TREND KEEPING THE BORDER DRY
AFTER 00Z. MID AND UPPER CLOUDS WILL BE LIFTING OFF TO THE NE AS
WELL SO SHOULD SEE DECREASING CLOUDS THROUGH THE NIGHT OVER THE
NORTH. THE PRESSURE GRADIENT WILL BE TIGHTENING TONIGHT...WHICH
WILL KEEP LOWS WARMER THAN LAST NIGHT. WILL GO WITH MID TO UPPER
40S FOR LOWS.
WEDNESDAY...UPSTREAM COLD FRONT WILL MOVE INTO THE NORTHERN
MISSISSIPPI VALLEY DURING THE AFTERNOON. WITH THE AREA FIRMLY IN
THE WARM SECTOR...WILL HAVE MID AND UPPER CLOUDS NORTH AND WEST OF
THE REGION...BUT SHOULD SEE MOSTLY CLEAR TO PARTLY CLOUDY SKIES FOR
THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AHEAD OF THE FRONT...AND
SOUTH WINDS WILL TURN GUSTY WITH DAYTIME HEATING AND MIXING. SOME
GUSTS COULD REACH 30 OR MAYBE EVEN 35 MPH. HIGHS TOMORROW IN THE
MID 70S TO LOW 80S.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY.
ONE OF THE FORECAST CHALLENGES FOR THIS PERIOD IS TRYING TO LASSO
IN THE LOCATIONS OF THE FRONT FOR THE MEMORIAL DAY WEEKEND.
ANOTHER ISSUE IS TIMING AND STRENGTH OF A SHORT WAVE TROUGH FOR
LATER THURSDAY AND ESPECIALLY THURSDAY NIGHT.
LITTLE CHANGE FROM THE GOING FORECAST FROM 24 HOURS AGO FROM
WEDNESDAY NIGHT INTO THURSDAY AS A SURFACE HIGH PRESSURE WITH UPPER
RIDGE DRIFTING OVER THE AREA WILL CONTINUE TO PROVIDE QUIET
WEATHER TO THE AREA. MODELS CONTINUE TO CONFINE CONVECTION OVER
THE NORTHERN PLAINS WITH THE BROAD UPPER TROUGH. PWATS GRADUALLY
INCREASE TO 1.75 ALONG THE FRONT OVER THE NORTHERN PLAINS. UNTIL
THIS UPPER RIDGE IS NUDGED FAR ENOUGH EAST...WILL CONTINUE TO
CONFINE ANY SMALL PCPN MENTION AND CLOUDS WEST OF A RHI TO AUW
LINE.
WILL THEN FOCUS ON HIGHER POPS FOR THE THURSDAY AFTERNOON INTO
THURSDAY NIGHT PERIOD AS A SHORT WAVE SLIDES OVER THE STATE. A
SURFACE LOW AND UPPER JET COUPLET PROGGED TO AFFECT THE NORTH
HALF OF THE STATE DURING THIS PERIOD PROVIDES SOME POTENTIAL OF
STRONG TO SEVERE STORMS. PROGS ARE A BIT MORE PROGRESSIVE WITH THE
FRONTAL PASSAGE LATE THURSDAY NIGHT. USING THE H8 FRONT...THE
FRONT IS DRIVEN SOUTH OF THE AREA FRIDAY INTO FRIDAY NIGHT FOR A
DIMINISHED PERIOD OF CONVECTION. PROGS IN GOOD AGREEMENT WITH H8
WARM FRONT LIFTING BACK NORTH AGAIN ON SATURDAY SO INCREASED
CONVECTION INCLUDING THUNDER FROM SOUTH TO NORTH DURING THE DAY.
PROGS CONTINUE TO LIFT THE FRONT NORTH TO GRADUALLY DIMINISH
CONVECTION OVER CENTRAL AND EAST CENTRAL WISCONSIN BUT WILL
CONFINE BEST PCPN CHANCES ACROSS THE NORTH SUNDAY AND PERHAPS INTO
MONDAY CLOSER TO THE WARM FRONT. AREAS TO THE SOUTH LIKELY TO BE
CAPPED IN A VERY WARM HUMID AIR MASS AS UPPER HEIGHTS BUILD.
ANOTHER FRONT IS PROGGED TO SLIDE OVER MONDAY INTO MONDAY NIGHT
FOR ANOTHER SHOT OF CONVECTION. PWATS INCREASE TO 1.70 INCHES
ALONG THE FRONT...HOWEVER AT THIS TIME IT APPEARS THE FRONTS ARE
A LITTLE TOO PROGRESSIVE FOR HEAVY RAINS TO CONCENTRATE IN ANY ONE
LOCATION WITH THE EXCEPTION OF THE FAR NORTH NEAR THE WARM FRONT.
&&
.AVIATION...HIGH PRESSURE WILL MOVE TO THE EASTERN GREAT LAKES WHILE
A COLD FRONT SHIFTS INTO THE NORTHERN MISSISSIPPI VALLEY BY LATE IN
THE TAF PERIOD. MID AND HIGH CLOUDS WILL PASS OVER NORTHERN
WISCONSIN THIS AFTERNOON...BUT AM NOT EXPECTING ANY PRECIP. VFR
CONDITIONS THROUGH THE REST OF THE TAF PERIOD...BUT WILL HAVE WIND
SHEAR DEVELOP OVER N-C WISCONSIN TONIGHT...AND SOUTH WINDS WILL TURN
GUSTY BY LATE MORNING TOMORROW.
MPC
&&
.MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED LATE
WEDNESDAY AFTERNOON INTO THURSDAY NIGHT. INCREASING SOUTH WINDS ARE
EXPECTED ON WEDNESDAY...THEN STRONG SOUTH WINDS ARE EXPECTED ON THURSDAY. A
FEW GUSTS COULD APPROACH GALE FORCE NEAR THE SHORELINE THURSDAY
AFTERNOON. WINDS AND WAVES WILL GRADUALLY SUBSIDE THURSDAY NIGHT.
FOR THE UPCOMING MEMORIAL DAY WEEKEND...IT WILL BE UNSETTLED AS
THERE WILL BE CHANCES FOR THUNDERSTORMS EACH DAY. A WARM FRONT
IS EXPECTED TO SLOWLY PUSH NORTHWARD INTO THE AREA OVER THE WEEKEND.
THERE IS A LOT OF UNCERTAINTY ON HOW FAR NORTH THE WARM FRONT WILL
MAKE IT INTO NORTHEAST WISCONSIN AND WHERE THE BEST CHANCES FOR
THUNDERSTORMS WOULD OCCUR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/TDH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 PM CDT MON MAY 21 2012
.SHORT TERM...TONIGHT THROUGH THURSDAY
325 PM CDT MON MAY 21 2012
MAIN FORECAST CONCERNS ARE FROST POTENTIAL TONIGHT AND PRECIPITATION
CHANCES AS WELL AS TEMPERATURES WEDNESDAY INTO THURSDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE DESERT SOUTHWEST INTO ALBERTA AND WEAK
TROUGHING OVER THE WESTERN GREAT LAKES REGION. HIGH PRESSURE
DOMINATES AT THE SURFACE ON THE BACK SIDE OF THE WEAK TROUGHING...
ENCOMPASSING THE ENTIRE FORECAST AREA. DRY AIR...SEEN ON THE 12Z
MPX...GRB AND DVN SOUNDINGS HAS RESULTED IN A SUNNY DAY ACROSS THE
FORECAST AREA. MIXING UP THROUGH 850MB WHERE TEMPS ARE AROUND 6C HAS
YIELDED TEMPERATURES MAINLY IN THE 70S...AND DEWPOINTS MOSTLY DOWN
INTO THE LOW TO MID 30S. TO THE WEST...AN AREA OF MID LEVEL CLOUDS
HAVE BEEN EXPANDING ACROSS NORTH DAKOTA AND INTO WESTERN MINNESOTA.
THESE CLOUDS ARE IN RESPONSE TO WARM ADVECTION AND MOISTURE RETURN
ON THE BACK SIDE OF THE SURFACE HIGH AND AHEAD OF THE UPPER RIDGE
AXIS. THERE WAS A LITTLE LIGHT SHOWER ACTIVITY ON THE WESTERN SIDE
OF THE CLOUDS...ASSOCIATED WITH 305 K ISENTROPIC LIFT...BUT THIS HAS
SINCE DISSIPATED. 12Z SOUNDINGS SHOWED MUCH WARMER AIR OVER THE
DAKOTAS...WITH 850MB TEMPS OF 10-15C ON AVERAGE WITH RAPID CITY AT
19C.
TONIGHT AND TUESDAY...UPPER RIDGING OVER THE NORTHERN ROCKIES WILL
SHIFT EAST INTO THE FORECAST AREA ON TUESDAY...PUSHED ALONG BY
TROUGHING CURRENTLY OFF THE PACIFIC NORTHWEST MOVING INLAND. IN
RESPONSE...A SURFACE LOW DEEPENS ACROSS THE DAKOTAS...INCREASING THE
WARM ADVECTION DOWNSTREAM INTO THE FORECAST AREA. WITH THIS WARM
ADVECTION WE SHOULD SEE SOME OF THOSE MID CLOUDS OVER WESTERN
MINNESOTA MOVE ACROSS. TRENDS IN MODEL RH FIELDS SUGGEST SOME
DISSIPATION OF THE MID CLOUDS AS THEY PUSH EAST...ESPECIALLY DURING
THE DAY TUESDAY. THIS MATCHES THE PREVIOUS FORECAST. IN ADDITION...
IT APPEARS MOST OF THE MID CLOUDS WILL STAY WEST OF THE MISSISSIPPI
RIVER TONIGHT. THIS IS CRITICAL BECAUSE THE SURFACE RIDGE SHOULD BE
CENTERED OVER WISCONSIN MUCH OF TONIGHT...LEADING TO FAVORABLE
RADIATIONAL COOLING CONDITIONS. SINCE BLACK RIVER FALLS AND SPARTA
DROPPED INTO THE LOW TO MID 30S LAST NIGHT...SEE NO REASON WHY THAT
WILL NOT HAPPEN AGAIN. THIS MEANS THAT OUR TYPICAL WISCONSIN COLD
SPOTS COULD SEE SOME FROST. NOT ENOUGH OF AN EXPANSIVE AREA OF COLD
TEMPS IS FORECAST TO WARRANT A FROST ADVISORY...THOUGH. WEST OF THE
MISSISSIPPI RIVER...INCREASING WINDS SHOULD ALLOW TEMPERATURES TO
STAY WARMER THERE. WITH INCREASING SUNSHINE AND SOUTHERLY WINDS ON
TUESDAY...AS WELL AS 850MB TEMPS CLIMBING TO AROUND 10C BY
18Z...SHOULD ALLOW FOR HIGHS WELL INTO THE 70S. WARMEST TEMPS LIKELY
WEST.
TUESDAY NIGHT AND WEDNESDAY...THE UPPER TROUGHING OVER THE NORTHWEST
U.S. IS PROGGED TO DEEPEN DURING THIS PERIOD. A FAIRLY POTENT
SHORTWAVE EJECTING OUT OF THIS TROUGH THROUGH THE DAKOTAS WILL CAUSE
THE LOW PRESSURE AREA THERE TO LIFT INTO NORTHWEST ONTARIO BY 00Z
THURSDAY. ITS ASSOCIATED COLD FRONT APPEARS TO BE TRENDING
SLOWER...NOW ONLY REACHING WESTERN MINNESOTA BY 00Z THURSDAY. THE
ECMWF HAS BEEN SUGGESTING THIS FOR QUITE AWHILE. ONLY MODEL THAT HAS
THE FRONT APPROACHING THE FORECAST AREA IS THE 21.12Z NAM...AND EVEN
IT HAS TRENDED SLOWER FROM ITS PREVIOUS RUNS. THEREFORE...HAVE
CONSIDERED THE NAM A FAST OUTLIER. ANY CONVECTION IS LIKELY TO BE
HIGHLY TIED TO THE FRONT...GIVEN CAPPING PRESENT IN THE WARM SECTOR
AHEAD OF IT. THEREFORE...HAVE DRIED OUT MUCH OF THE FORECAST EXCEPT
FOR A SMALL AREA IN SOUTHEAST MINNESOTA WHICH IS CLOSEST TO THE
FRONTAL BOUNDARY. THESE SMALL CHANCES MAY BE ABLE TO BE PULLED IN
LATER FORECASTS. A BREEZY SOUTH WIND WILL HELP KEEP TEMPERATURES UP
TUESDAY NIGHT INTO THE 50S IN MOST LOCATIONS. SOME OF SOUTHEAST MN
MAY NOT DROP BELOW 60...MEANWHILE THE COLD SPOTS OF WISCONSIN COULD
DECOUPLE AND DROP INTO THE UPPER 40S. MUCH WARMER 850MB TEMPS ARE
PROGGED FOR WEDNESDAY...ON THE ORDER OF 16-18C. NORMALLY THIS COULD
PRODUCE HIGHS OF 85 TO 90. HOWEVER...THERE IS INCREASING CIRRUS
THROUGH THE DAY TO TEMPER HIGHS SOMEWHAT.
WEDNESDAY NIGHT AND THURSDAY...ANOTHER SURFACE LOW IS PROGGED TO
FORM OVER SOUTHEAST COLORADO LATE WEDNESDAY. A POTENT SHORTWAVE
EJECTING OUT OF THE DEEPENING WESTERN TROUGH WILL LIFT THIS LOW
NORTHEAST...RIDING UP THE COLD FRONT AND CROSSING CENTRAL MINNESOTA
ON THURSDAY. THE 21.12Z GFS/UKMET BOTH DEPICT SOME QPF WEDNESDAY
NIGHT OVER WISCONSIN...BUT THESE SEEM ODD GIVEN OUR FORECAST AREA IS
UNDERNEATH THE MAIN MOISTURE TRANSPORT STREAM WITHOUT MOISTURE
CONVERGENCE...AS WELL AS CAPPING ALOFT TO ELEVATED CONVECTION.
THEREFORE...FOR WEDNESDAY NIGHT...KEPT ALL PRECIPITATION CHANCES
OVER FAR NORTHWEST SECTIONS OF THE FORECAST AREA. THESE CHANCES ARE
STILL LOW...20-30...BECAUSE THE FRONTOGENETICAL ZONE ASSOCIATED WITH
THE COLD FRONT LOOKS TO STAY ACTIVE ALONG AND NORTHWEST OF
IT...WHICH KEEPS THE BULK OF THE PRECIPITATION MORE FROM SOUTHWEST
MINNESOTA INTO THE DULUTH AREA. BETTER SHOT EXISTS FOR THE COLD
FRONT TO COME IN ON THURSDAY...IN THIS CASE ASSOCIATED WITH THE NEW
LOW COMING UP. THE 21.12Z GFS REMAINS THE FASTEST MODEL TO DO
SO...WITH THE ECMWF AND ESPECIALLY GEM SUGGESTING SLOWER. LEANED
TOWARDS THE SLOWER PASSAGE...WHICH KEEPS ALL PRECIPITATION CHANCES
OVER THE NORTHWEST HALF OF THE FORECAST AREA. TEMPERATURES BOTH
WEDNESDAY NIGHT AND ESPECIALLY THURSDAY HAVE BEEN WARMED UP...DUE TO
THE SLOWER FRONTAL PASSAGE AND MAINTAINING A LONGER PERIOD OF BREEZY
SOUTH WINDS. THURSDAY COULD TOUCH 90...ESPECIALLY IN THE SOUTHEAST
WHERE MORE SUN IS PRESENT TO COMBINE WITH 850MB TEMPS UP POSSIBLY
NEAR 20C.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
325 PM CDT MON MAY 21 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES AND WHEN THE
HEAT UP WILL COME.
MODELS ARE BECOMING IN MUCH BETTER AGREEMENT ON THE LONG TERM
FORECAST...SO CONFIDENCE IS INCREASING ON WHAT WILL HAPPEN. IN
GENERAL...TROUGHING LOOKS TO REMAIN IN THE WESTERN U.S....
INTENSIFYING BY SATURDAY MORNING. WITH THE DEEPENING TROUGH OUT
WEST...THE RESPONSE IS TO BUILD SOME PRETTY STRONG RIDGING TO THE
EAST. THEREFORE...AFTER WHAT LOOKS TO BE A COLD FRONTAL PASSAGE
THURSDAY NIGHT...THAT COLD FRONT WILL NOT BE ABLE TO DROP TOO FAR
SOUTH. MAINTAINED SOME CHANCES OF SHOWERS AND THUNDERSTORMS FOR
THURSDAY NIGHT...AND THESE MAY NEED TO BE INCREASED OVER WESTERN
SECTIONS WITH A SHORTWAVE PROGGED TO COME OUT. IN FACT...IF THE
21.12Z ECMWF/GEM ARE CORRECT...SOME OF THE STORMS THURSDAY NIGHT
COULD BE SEVERE. WESTERN SECTIONS OF THE AREA LOOK TO GET A BREAK
FROM PRECIPITATION ON FRIDAY WITH THE FRONT PASSED...BUT STILL
MAINTAINED A CHANCE ELSEWHERE SINCE THE FRONT IS STILL MOVING
THROUGH. DEFINITELY COOLER ON FRIDAY BEHIND THE FRONT...BUT STILL
SEASONABLE. FRONT SHOULD LAY UP IN SOUTHERN IOWA FRIDAY NIGHT AND
THEN BEGIN TO RETREAT NORTH AS A WARM FRONT AS THE UPPER RIDGE
STRENGTHENS. MOISTURE TRANSPORT NORTH OF THE FRONT COULD YIELD
CONVECTION FRIDAY NIGHT THROUGH SATURDAY. CANNOT RULE OUT SOME OF
THIS BEING SEVERE TOO. 850MB TEMPS CLIMB TO 20C OR HIGHER SOUTH OF
THE FRONT...WHICH MEANS ON SATURDAY THERE IS POTENTIAL FOR A 20
DEGREE OR MORE SPREAD ACROSS THE FORECAST AREA.
MODELS AGREE THAT THE WESTERN TROUGH BEGINS EJECTING OUT SATURDAY
NIGHT...ALLOWING THE RIDGE AND WARM SECTOR TO BUILD OVER THE
FORECAST AREA. THIS MEANS THE CONVECTION SHOULD SLOWLY SHIFT
NORTH...ALLOWING FOR HEAT AND LIKELY SOME HUMIDITY TO MOVE IN.
RAISED HIGHS ON SUNDAY TO THE MID 80S TO NEAR 90...BUT FURTHER
INCREASES COULD BE NEEDED. SAME GOES FOR LOWS SATURDAY NIGHT AND
SUNDAY NIGHT WHERE POTENTIAL EXISTS FOR TEMPERATURES TO NOT DIP
BELOW 70. LAST ISSUE IS A COLD FRONT PROGGED TO COME AT THE AREA FOR
SUNDAY NIGHT AND MONDAY...ASSOCIATED WITH THE EJECTING WESTERN
TROUGH. THE GFS IS THE FASTEST ON THIS FRONT...WHEREAS THE 21.12Z
ECMWF HAS SLOWED DOWN FROM ITS PREVIOUS RUN. FOR NOW HAVE FOLLOWED A
CONSENSUS AND INCLUDED 20-40 PERCENT CHANCES FOR SUNDAY NIGHT AND
MONDAY. HOWEVER...WOULD NOT BE SURPRISED IF THE SLOWER FRONTAL
TIMING PANS OUT...RESULTING IN A WARMER AND DRIER FORECAST.
IN SUMMARY...SOME POTENTIAL FOR SEVERE STORMS THURSDAY NIGHT AND
FRIDAY NIGHT/SATURDAY...THEN HEATING UP FOR THE END OF MEMORIAL DAY
WEEKEND.
&&
.AVIATION...THROUGH 06Z WEDNESDAY
1145 PM CDT MON MAY 21 2012
HIGH PRESSURE WILL MOVE EAST INTO EASTERN WISCONSIN OVERNIGHT. AS
THIS OCCURS...THE WINDS WILL SHIFT TO THE SOUTH AND THEN INCREASE
ON TUESDAY MORNING AS THE PRESSURE GRADIENT TIGHTENS ON THE BACK
SIDE OF THE HIGH PRESSURE. AS DIURNAL MIXING OCCURS...THE WIND
GUSTS ACROSS SOUTHEAST MINNESOTA WILL CLIMB INTO THE 20 TO 30 KNOT
RANGE...AND 15 TO 25 KNOTS ACROSS WESTERN WISCONSIN. WITH THE LOSS
OF DIURNAL HEATING DURING THE EARLY EVENING...THE WIND GUSTS WILL
QUICKLY SUBSIDE AT BOTH LOCATIONS.
OTHER THAN OCCASIONALLY BOUTS OF SCATTERED 10-20K CLOUDS...SKIES
WILL BE MOSTLY CLEAR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 PM CDT MON MAY 21 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1055 PM MDT WED MAY 23 2012
.UPDATE...
ISSUED AT 1035 PM MDT WED MAY 23 2012
WINDS HAVE SUBSIDED TO BELOW ADVISORY CRITERIA OVER THE LAST 30
MINUTES SO CANCELLED THE ADVISORY. THE RED FLAG WARNING HAS ALSO
BEEN CANCELLED AS MOST OBS SHOWING RH/S ABOVE 15 PERCENT WITH MOST
AREAS SHOWING WINDS BELOW 25 MPH THOUGH OCCNL GUSTS ABOVE THAT
THRESHOLD CONTINUE. THE COLD FRONT HAS JUST ABOUT REACHED NEW
MEXICO THIS EVENING WITH SOME RESIDUAL MOISTURE STILL CAUSING SOME
SHOWERS ALONG THE I-70 CORRIDOR AND EVEN SNOWFALL AROUND VAIL
PASS. THESE SHOULD END IN THE NEXT FEW HOURS. CURRENT FORECAST
CAPTURES ALL THIS QUITE WELL SO NO CHANGES EXPECTED AT THIS TIME.
UPDATE ISSUED AT 926 PM MDT WED MAY 23 2012
THE COLD FRONT IS SWEEPING SOUTH ACROSS SE UTAH/SW COLORADO. AT
03Z THIS EVENING...THE COLD FRONT IS PASSING THE DURANGO AIRPORT.
WHILE WINDS ARE EXPECTED TO SUBSIDE IN THE POST FRONTAL AIR
MASS...WINDS STILL FAIRLY STRONG AND ELECTED TO EXTEND THE RED
FLAG WARNING AND WIND ADVISORY THROUGH 11 PM.
THE VAIL PASS WEB CAM SHOWED LIGHT SNOW ACCUMULATION ON THE GRASSY
AND DIRT SURFACES. HIGH MOUNTAIN REMOTE SENSORS INDICATE THAT
TEMPERATURES ARE AROUND 32F AND INDICATE THAT SNOW ACCUMULATIONS
WILL BE FAIRLY COMMON ABOVE 10K FEET. THE BRUNT OF THE
PRECIPITATION OCCURS BEFORE MIDNIGHT WITH THE HRRR SHOWING FAST
DROP OFF IN QPF AMOUNTS AFTER 06Z. ELECTED TO ISSUE SPECIAL
WEATHER STATEMENT TO ADDRESS THE IMPACT OF LATE SEASON SNOWFALL
INSTEAD OF HOIST A WINTER WEATHER ADVISORY. WIDESPREAD SNOW ABOVE
10K FEET IS EXPECTED TO TAPER OFF WITHIN THE NEXT 2-3 HOURS (AND
PAVEMENTS MAY STAY WET WITH SLUSHY AREAS).
UPDATE ISSUED AT 723 PM MDT WED MAY 23 2012
AS THE NOSE OF JET PUNCHES INTO WRN COLORADO...PRECIPITATION HAS
INCREASED ACROSS PARTS OF NORTHWEST AND WEST CENTRAL COLORADO.
RAISED POPS TO ACCOUNT FOR THIS INCREASE...ALTHOUGH TRACE AMOUNTS
MAY BE THE ONLY RAINFALL THE LOWER VALLEYS RECEIVE AS THE EVENING
SOUNDING SHOWS A MOSTLY DRY SUB CLOUD LAYER. HOWEVER PRECIPITABLE
WATER DID RISE TO ONE HALF INCH. THESE SHOWERS HAVE ENHANCED GUSTY
WINDS IN THE CENTRAL VALLEY WITH LOCAL GUSTS TO 40 MPH. FARTHER
SOUTH...GUSTY WINDS HAVE BEEN STRONGER WITH GUSTS OF 45 TO 50 MPH
FAIRLY COMMON. NO UPDATES TO THE WIND ADVISORY THAT EXPIRES AT
9 PM MDT THIS EVENING.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM MDT WED MAY 23 2012
LARGE SCALE ASCENT IS INCREASING OVER NORTHERN UTAH INTO NORTHWEST
COLORADO AHEAD OF THE MID LEVEL TROF AXIS DROPPING THROUGH THE
GREAT BASIN. DARKENING IN THE WATER VAPOR IMAGERY SHOWING THIS
LIFT BEING ENHANCED BY ARRIVING JET MAX AND ASSOCIATED PV LOBE
WITH INCREASING INSTABILITY FROM DAYTIME HEATING AND COOLER AIR
MOVING IN WITH THE TROF ALSO AIDING ASCENT. 88D MOSAIC IS
RESPONDING BY SHOWING AN INCREASE IN COVERAGE MAINLY NORTH OF A
MOAB TO MONTROSE TO GUNNISON LINE WHICH IS NEAR WHERE THE SURFACE
FRONT HAS SETTLED AND MAY BE WAVERING. THIS LIFT SEEMS TO BE
HELPING TO MIX OUT THE ATMOSPHERE NORTH OF FRONT AS WELL WITH
WINDS PICKING UP AT GJT THE PAST HOUR OR SO. SOME GUIDANCE
INDICATING VERY GUSTY WINDS THROUGH EARLY EVENING ACROSS THE GRAND
VALLEY AND WILL CONTINUE TO MONITOR. FARTHER SOUTH IN ADVISORY
REGION STRONG MIXING AHEAD OF THE FRONT HAS BEEN PUSHING WIND
GUSTS NEAR 45 MPH AND EXPECT THE NEXT FEW HOURS THEY COULD
CONTINUE TO STRENGTHEN SO WILL LEAVE ADVISORY AS IS. AS FOR
PRECIPITATION THE BEST FOCUS CONTINUES TO POINT AT THE NORTHERN
AND CENTRAL MOUNTAINS THROUGH THIS EVENING WHERE MID LEVEL LAPSE
RATES WILL CONTINUE TO STEEPEN UNDER THE STRONGER DYNAMICS ALOFT.
MOISTURE IS ALREADY IN PLACE NORTH OF THE FRONT SO SHOULD NOT TAKE
MUCH TO GET PRECIPITATION TO THE SURFACE. ONE CAVEAT HOWEVER IS DRIER
AIR IS ADVECTING IN A LOW LEVELS FROM WYOMING SO WILL KEEP THE
HIGHEST POPS ON THE TERRAIN WHERE OROGRAPHICS WILL ALSO CONTINUE
INTO THE THURSDAY MORNING AS THE UPPER SUPPORT LIFTS OUT OF OUR
REGION. WOULD NOT BE SURPRISED TO SEE SOME LIGHT SNOW ABOVE THE
9000 FT LEVEL BUT SHOULD NOT ANTICIPATING A LARGE IMPACT ATTM WITH
AN INCH OR LESS LIMITED TO THE VEGETATION. THE SURFACE FRONT WILL
BE SAGGING THROUGH THE SOUTHERN CWA TONIGHT AS WELL AND THIS MAY
HELP TRIGGER SOME ISOLATED CONVECTION IN THE SOUTHERN
MOUNTAINS...BUT CONFIDENCE NOT HIGH SO POPS REFLECT THIS.
TEMPERATURES WILL BE QUITE COOL COMPARED TO THE PAST FEW NIGHTS
WITH SOME VALLEYS IN THE NORTH DROPPING TO NEAR THE FREEZING MARK.
WITH THE FRONT NEAR THE SOUTHERN BORDER ON THURSDAY AND COOLER DAY
LOOKS ON TRACK AND THERE SHOULD BE A FAIR AMOUNT OF SUNSHINE IN
PLACE BEFORE AFTERNOON HEATING STARTS POPPING THE CUMULUS. THE
EXCEPTION WILL BE OVER THE FAR NORTHERN MOUNTAINS EARLY DUE TO THE
MOIST DENDRITIC FLOW AND COLD POOL ALOFT WHICH SHOULD PRODUCE SOME
LIGHT PRECIPITATION. HIGHS ACTUALLY LOOK TO BE RUN NEAR OR BELOW
NORMAL OUTSIDE THE 4 CORNERS REGION AND DID USE A BLEND OF GUIDANCE.
A STRONGER WESTERN SYSTEM WILL BE PUSHING INTO THE EASTERN GREAT
BASIN TOMORROW NIGHT. THIS WILL QUICKLY BACK AND INCREASE THE FLOW
TO THE SOUTHWEST AND PUSH THE WARM FRONT STRUCTURE BACK NORTHWARD
THROUGH THE CWA. ATTM THE MODELS ARE PUTTING OUT SOME LIGHT
PRECIPITATION BUT MODEL SOUNDINGS WOULD INDICATE THIS IS MOSTLY IN
THE FORM OF ACCAS MOVING OVERHEAD IN THE STRONG WAA PATTERN. FOR NOW
JUST PUT IN SOME ISOLATED MENTION OVER THE HIGHEST TERRAIN IN THE
NORTHEAST CWA. BETTER MIXING AND THE WAA SHOULD PUSH LOWS UP A FEW
DEGREES OVER TONIGHT/S READINGS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM MDT WED MAY 23 2012
MODELS REMAIN CONSISTENT ON DROPPING THE NEXT PACIFIC TROUGH INTO
THE WESTERN GREAT BASIN FRIDAY AND THEN LIFTING IT OUT TO THE
NORTHEAST THIS WEEKEND...DRAGGING A COLD FRONT ACROSS SAT OR SAT
EVENING. NOT A LOT OF MOISTURE INDICATED WITH THIS FRONT...SO JUST
SLIGHT CHANCE TO CHANCE POPS FOR MAINLY NE UT AND NW CO SHOULD
SUFFICE FOR NOW. ABOVE NORMAL TEMPS FOR FRIDAY AS WARM ADVECTION
RETURNS. WITH THE MAIN UPPER LOW LIFTING OUT WELL TO OUR NW...MAY
SEE THE EASTWARD PROGRESSION OF THE COLD FRONT SLOW ON SATURDAY SO
WILL KEEP MAX TEMPS ON THE WARM SIDE SAT OVER ALL BUT NE UT.
THE BIGGEST IMPACT WILL LIKELY BE THE SOUTH TO SOUTHWEST WIND...
WHICH IS EXPECTED TO STRENGTHEN SIGNIFICANTLY FRIDAY THROUGH
SATURDAY. BOTH NAM AND GFS SHOW 40-45 KTS AT 700 MB...WITH SOME
AREAS OF 50-55 KTS WINDS INDICATED FRI NIGHT. WIND ADVISORIES MAY BE
NEEDED...AND A FIRE WEATHER WATCH HAS ALREADY BEEN ISSUED FOR FRI
AND SAT.
COOLER TEMPERATURES FOLLOW FOR SUNDAY BEHIND THE FRONT WITH A CHANCE
OF SHOWERS PERSISTING FOR THE NORTHERN MTNS IN THE WEST TO NW FLOW.
DRY WESTERLY FLOW EXPECTED MONDAY THROUGH WEDNESDAY WITH
TEMPERATURES WARMING UP AGAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 345 PM MDT WED MAY 23 2012
SHOWERS SHOULD BE ENDING IN THE NEXT FEW HOURS ALONG WITH THE LOW
TO MID CEILINGS THAT ARE OVER MUCH OF THE CWA. IFR CONDITIONS AT
KASE THIS HOUR DUE TO SNOW SHOULD ALSO BECOME VFR OVER THE NEXT
FEW HOURS AS SHOWERS END. FOR TOMORROW...VFR WILL BE FELT ACROSS
ENTIRE CWA AS ZONAL FLOW SETS UP.
&&
.FIRE WEATHER...
ISSUED AT 345 PM MDT WED MAY 23 2012
RED FLAG WARNING CONTINUES FOR SOUTHWEST AND PORTIONS OF
WEST-CENTRAL CO THROUGH THIS EVENING.
THURSDAY LOOKS LIKE A BIT OF DOWN DAY WITH SLIGHTLY WEAKER WINDS
ALOFT AND AT THE SURFACE...THOUGH LOCALIZED BORDERLINE CRITICAL
CONDITIONS WILL BE POSSIBLE IN SOUTHWEST CO.
WINDY AND DRY CONDITIONS LOOK IN STORE FOR FRIDAY AND SATURDAY AS
THE NEXT STORM DROPS INTO THE GREAT BASIN. THE FIRE WEATHER WATCH
CURRENTLY STARTING FRIDAY AFTERNOON HAS NOW BEEN EXTENDED UNTIL
SATURDAY EVENING. AM CONCERNED THAT WINDS WILL PERSIST FRIDAY NIGHT
AT LEAST ACROSS THE MID-SLOPES AND THERMAL BELTS WHERE HUMIDITY
RECOVERY MAY BE THE POOREST. DO NOT DOUBT THAT THERE WILL BE A
PERIOD OF NON-CRITICAL CONDITIONS LATER FRIDAY NIGHT ESPECIALLY FOR
VALLEYS...BUT WITH ANY VALLEY INVERSIONS BEING SHALLOW AND EASILY
MIXED OUT...CRITICAL FIRE WEATHER CONDITIONS COULD RETURN AS EARLY
AS MID-MORNING SATURDAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
EVENING FOR COZ200>203-207-290-292-293.
UT...NONE.
&&
$$
UPDATE...TGR
SHORT TERM...15
LONG TERM...JAD
AVIATION...TGR
FIRE WEATHER...JAD
AREA FORECAST DISCUSSION
NWS MIAMI FL
217 AM EDT THU MAY 24 2012
.AVIATION...
ISOLATED TO SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE TODAY...MAINLY OVER THE EAST COAST TERMINALS...AS MOST OF
THE DEEP LAYER MOISTURE REMAINS EAST OF THE PENINSULA ACROSS THE
BAHAMAS. WILL INCLUDE VCSH/VCTS IN THIS PACKAGE THROUGH THE
AFTERNOON PERIOD AND UPDATE AS NEEDED. PERIODS WITH MVFR
CIGS/VSBYS WILL BECOME POSSIBLE IN AND AROUND ANY MODERATE TO
HEAVY SHOWER/TSTM THAT DEVELOP THROUGH THIS PERIOD. WITH THE
TROUGH AXIS OVER THE AREA...MAINLY LIGHT WINDS WILL BE EXPECTED
WITH AFTERNOON SEA BREEZES ANTICIPATED ALONG THE GULF AND ATLANTIC
COASTS. 85/AG
&&
.PREV DISCUSSION... /ISSUED 951 PM EDT WED MAY 23 2012/
UPDATE...CHALLENGING FORECAST. LOCAL AREA HAS COME UNDER
SUBSIDENCE TODAY AS EVIDENCED BY LITTLE CONVECTION. WE WERE IN THE
SUBSIDENCE SIDE OF A DEPARTING JET. 500 MB TEMP HAS WARMED QUITE A
BIT...NOW AT -6.9C ON THE EVENING MIAMI SOUNDING. SO NOT AS
UNSTABLE. CONVECTION HAS REMAINED GENERALLY OFF THE SE FL COAST
ALL DAY, THOUGH A FEW SHOWERS AND STORMS DID DEVELOP OVER THE
INTERIOR AND GULF COAST. CONVECTION OVER THE ATLANTIC HAS NOW EVEN
DIMINISHED. HOWEVER, THERE IS A SHORTWAVE OVER THE NORTH CENTRAL
GULF HEADING ESE...AND MODELS INDICATE MORE FAVORABLE JET DYNAMICS
LATE TONIGHT AND ESPECIALLY THURSDAY. HOWEVER, GFS/ECMWF CONSENSUS
IS TO KEEP THE BEST CONVERGENCE/HEAVY RAIN JUST OFF TO OUR
SOUTHEAST...AS A SURFACE/LOW LEVEL TROUGH AXIS LIES ALONG THE SE
FL COAST. BUT SE FLOW IS STRENGTHENING SOME AND THIS COULD
INCREASE COASTAL CONVERGENCE ALONG THE ATLANTIC COAST OVERNIGHT.
THE LATEST HRRR SHOWS SHOWERS DEVELOPING AND MOVING NW ONSHORE THE
ATLANTIC COAST LATER TONIGHT, ALTHOUGH IT`S OVERDOING ACTIVITY
CURRENTLY.
SO HERE`S THE BOTTOM LINE - THE MOST FAVORED AREA OVERNIGHT
THROUGH THURSDAY FOR HEAVY RAIN LOOKS TO BE OFF OUR ATLANTIC
COAST. HOWEVER, GIVEN HIGH MOISTURE AND POSSIBLE COASTAL
CONVERGENCE, WILL MAINTAIN POPS AS IS. STILL LIKE THE FLOOD WATCH
FOR MIAMI- DADE COUNTY THROUGH 8 PM THU...GIVEN THE EXTREME
RAINFALL WHICH OCCURRED FROM THE SWEETWATER-DORAL AREAS ON TUESDAY
WITH STANDING WATER REMAINING IN AREAS. IT WON`T TAKE MUCH RAIN TO
CAUSE FLASH FLOODING ACROSS THESE HARD HIT LOCALES. /GREGORIA
PREV DISCUSSION... /ISSUED 741 PM EDT WED MAY 23 2012/
AVIATION...
SOUTH FLORIDA IS AT THE EDGE OF DEEP TROPICAL MOISTURE TO THE EAST
AND ISOLATED CONVECTIVE ACTIVITY TO THE WEST. THE EAST COAST
TERMINALS INCLUDE VCSH AFTER MIDNIGHT SINCE MOST GUIDANCE INSISTS
IN INCREASING THE SHOWER ACTIVITY OVER NIGHT NEAR THE EAST COAST.
HOWEVER, THIS IS A LOW CONFIDENCE FORECAST. FOR THURSDAY WE EXPECT
SHOWERS AND THUNDERSTORMS TO BECOME MORE WIDESPREAD IN THE
AFTERNOON AND EVENING. ALL TAF LOCATIONS INCLUDE THE CHANCE FOR
VCTS FOR THURSDAY AFTERNOON. WINDS ARE EXPECTED TO BE FROM THE
EAST SOUTHEAST BELOW 10 KNOTS.
PREV DISCUSSION... /ISSUED 659 PM EDT WED MAY 23 2012/
UPDATE...CONVECTION TODAY HAS BEEN VERY MINIMAL DUE TO BROAD
SCALE SUBSIDENCE. HOWEVER, AS A SHORTWAVE OVER THE NORTH CENTRAL
GULF AS SEEN ON WATER VAPOR IMAGERY IS MOVING RATHER FAST TO THE
EAST. THIS COULD INDUCE SOME OF THE HIGHER MOISTURE OVER THE
ATLANTIC, AND ASSOCIATED RAINFALL, TO MOVE TOWARDS THE NW AND
ONSHORE THE SE FLORIDA COAST OVERNIGHT. UNCERTAIN FORECAST TONIGHT
AND THURSDAY AS WE ARE ON THE EDGE OF DEEP CARIBBEAN MOISTURE AND
TROUGH AXIS. WILL MAINTAIN THE CHANCE POPS TONIGHT. FLOOD WATCH
REMAINS IN EFFECT FOR MIAMI-DADE COUNTY THROUGH 8 PM THURSDAY FOR
THE POTENTIAL FOR ADDITIONAL RAINS LEADING TO FLASH FLOODING.
/GREGORIA
PREV DISCUSSION... /ISSUED 348 PM EDT WED MAY 23 2012/
FLOOD WATCH EXTENDED UNTIL THURSDAY EVENING FOR MIAMI-DADE COUNTY...
POSSIBLE STRONG TO EVEN SEVERE STORMS FOCUSED INTERIOR THIS AFTERNOON...
DISCUSSION...
EARLY THIS AFTERNOON...A MID TO UPPER LEVEL LOW WAS LOCATED OVER THE
CAROLINAS WITH A TROUGH OF LOW PRESSURE EXTENDING SOUTHWEST
THROUGH THE CWA AND INTO THE NORTHWEST CARIBBEAN SEA WHERE A WEAK
SURFACE LOW PRESSURE SYSTEM WAS LOCATED. THE NATIONAL HURRICANE
CENTER AT THIS TIME IS GIVING THE SURFACE LOW IN THE NORTHWEST
CARIBBEAN SEAS A NEAR 0 PERCENT CHANCE OF DEVELOPMENT DURING THE
NEXT 48 HOURS.
THE MID TO UPPER LEVEL LOW WILL MOVE NORTHEAST KEEPING THE TROUGH
OF LOW PRESSURE IN PLACE OVER THE CWA TONIGHT INTO THURSDAY...AS
THE WEAK SURFACE LOW MOVES NORTHEAST AND THROUGH SOUTH FLORIDA OR
JUST TO THE EAST OF SOUTH FLORIDA. THIS WILL KEEP THE STEERING
FLOW IN PLACE ALONG WITH THE DEEP TROPICAL MOISTURE WORKING INTO
THE SOUTHERN PORTION OF THE CWA FROM THE NORTHWEST CARIBBEAN SEA.
THE LATEST PWAT`S FROM THE FORECAST MODELS ARE STILL SHOWING 2 TO
2.4 INCHES OVER THE SOUTHERN AREAS OF THE CWA LATE TONIGHT INTO
THURSDAY WHICH IS CLOSE TO THE ALL TIME MAXIMUM PWAT FOR THIS
TIME OF YEAR. THIS WILL ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS
TO CONTINUE OVER THE EAST COAST METRO AREAS TAPERING DOWN TO
ISOLATED OVER THE INTERIOR AND WEST COAST METRO AREAS. ON
THURSDAY...THE ACTIVITY COULD INCREASE TO SCATTERED COVERAGE OVER
THE INTERIOR AREAS TO NUMEROUS COVERAGE OVER THE EAST COAST METRO
AREAS. THEREFORE...A FLOOD WATCH FOR MIAMI-DADE COUNTY HAS BEEN
EXTENDED THROUGH THURSDAY EVENING...DUE TO THE GROUND BEING VERY
SATURATED FROM THE PREVIOUS RAINS OVER THE PAST COUPLE OF DAYS AND THE
POTENTIAL OF MORE LOCALLY HEAVY RAINFALL TONIGHT INTO THURSDAY.
THE WEAK LOW WILL THEN MOVE INTO WESTERN ATLANTIC WATERS PUSHING
THE TROUGH OF LOW PRESSURE SOUTHWARD INTO THE FLORIDA KEYS. THIS
WILL ALLOW FOR DRIER AIR TO WORK INTO THE CWA FROM THE NORTH FOR
FRIDAY INTO THIS WEEKEND WHICH IN TURN WILL REDUCE THE COVERAGE OF
THE SHOWERS AND THUNDERSTORMS OVER THE CWA. THE BEST CHANCE OF
SHOWER AND THUNDERSTORM ACTIVITY WILL BE OVER THE INTERIOR AND
WEST COAST METRO AREAS THIS WEEKEND...DUE TO THE NORTHEAST
STEERING FLOW BEHIND THE TROUGH OF LOW PRESSURE.
EXTENDED FORECAST...
THE LATEST LONG RANGE MODELS ARE NOW SPLITTING ON THE RETURN
MOISTURE TO THE AREA FOR EARLY TO MIDDLE OF NEXT WEEK. THE 23/00Z
RUN OF THE ECMWF LONG RANGE MODEL TRIES TO BRING THE LOW BACK TO THE
FLORIDA PENINSULA ALONG WITH THE DEEP MOISTURE...WHILE THE 23/12Z GFS
MODEL PUSHES THE LOW EASTWARD TAKING THE DEEP TROPICAL MOISTURE
WITH IT. SO AT THIS TIME WILL CONTINUE TO SHOW SCATTERED SHOWERS
AND THUNDERSTORMS OVER THE CWA FOR EARLY TO MIDDLE OF NEXT
WEEK...UNTIL THE MODELS BECOME MORE IN LINE WITH EACH OTHER FOR
EARLY TO MIDDLE OF NEXT WEEK.
MARINE...
THE WINDS OVER THE CWA WATERS WILL REMAIN AT 15 KNOTS OR LESS
TONIGHT INTO THIS WEEKEND WHILE SWINGING FROM A SOUTHERLY
DIRECTION TONIGHT TO A NORTHERLY DIRECTION THIS WEEKEND. THE ONLY
EXCEPTION TO THIS IS IN THE ATLANTIC WATERS WHERE THE WINDS WILL
BE 15 TO 20 KNOTS TONIGHT. THE SEAS WILL ALSO REMAIN BELOW 6 FEET
FOR BOTH THE ATLANTIC AND GULF WATERS OF SOUTH FLORIDA TONIGHT
THROUGH THIS WEEKEND. SO WILL CONTINUE THE SCEC FOR THE ATLANTIC
WATERS DUE TO THE WIND SPEEDS.
FIRE WEATHER...
THE RELATIVE HUMIDITIES WILL REMAIN ABOVE THE 35 PERCENT CRITICAL
VALUE THROUGH THE WEEKEND. SO NO PROBLEMS WITH THE FIRE WEATHER
PRODUCT.
HYDROLOGY...
FOR DETAILS ON THE RAINFALL AMOUNTS ACROSS SOUTH FLORIDA PLEASE SEE
THE FLOOD WATCH AND THE HYDROLOGIC OUTLOOK STATEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 75 89 77 / 50 30 20 20
FORT LAUDERDALE 86 77 88 78 / 70 40 20 20
MIAMI 87 76 89 77 / 70 40 20 20
NAPLES 89 74 90 74 / 40 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH THIS EVENING FOR COASTAL MIAMI DADE-FAR
SOUTH MIAMI DADE-INLAND MIAMI DADE-METRO MIAMI DADE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...15/JR
AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
241 AM EDT THU MAY 24 2012
.SYNOPSIS...
A WEAK SURFACE TROUGH WILL REMAIN OVER THE REGION TODAY. UPPER LEVEL
HIGH PRESSURE WILL BEGIN TO BUILD INTO OUR REGION FRIDAY THROUGH
SUNDAY...WHILE LOW PRESSURE DEVELOPS AND REMAINS OFFSHORE. THE UPPER
HIGH WILL WEAKEN BY EARLY NEXT WEEK. THIS...ALONG WITH THE
POSSIBILITY OF INCREASING ATMOSPHERIC MOISTURE...AND THE APPROACH OF
A COLD FRONT...MAY RESULT IN INCREASED PRECIPITATION CHANCES EARLY
TO MID NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
IT APPEARS A WEAK SURFACE TROUGH/DEWPOINT GRADIENT CONTINUES TO
STRETCH GENERALLY ACROSS THE SE PART OF THE FORECAST AREA (FA).
UPPER LOW JUST TO OUR NORTH...WITH A PAIR OF VORTS THAT THE
MODELS GENERALLY KEEP TO OUR NORTH TODAY. DRY MID LEVEL AIR OVER
THE FA APPARENT ON SATELLITE WATER VAPOR IMAGERY. MODEL GUIDANCE
GENERALLY SUGGESTS A DRY ATMOSPHERE OVER MOST OF OUR FA...WITH
SOME MID LEVEL CAPPING NOTED. MODELS INDICATE A WEAK SE LOW LEVEL
SYNOPTIC FLOW THAT COULD BRING THE WEAK TROUGH NORTH A LITTLE...AS
WELL AS AIDING A SEA BREEZE BOUNDARY MAKING IT INTO OUR FA. LOCAL
MODEL AND OTHER GUIDANCE SUGGESTS A FEW SHOWERS...AND A POSSIBLE
THUNDERSTORM...THAT COULD DEVELOP ALONG THE SURFACE TROUGH OR SEA
BREEZE THIS AFTERNOON. WILL MAINTAIN SLIGHT CHANCE POPS FOR
SHOWERS AND ISO TS...MAINLY SE TIER.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
BY TONIGHT AND FRIDAY...MODELS INDICATE UPPER LEVEL TROUGH TO SHIFT
TO OUR EAST...WITH AN UPPER LOW CUTTING OFF...AND A SURFACE LOW
DEVELOPING...OFFSHORE THE CAROLINAS. UPPER HIGH TO DEVELOP OVER
THE LOWER MISSISSIPPI VALLEY. THIS WILL RESULT IN SOME UPPER
HEIGHT RISES FOR OUR FA...GENERALLY KEEPING OUR FA DRY AND
CAPPED. UPPER HIGH CENTER TO SHIFT NE SLIGHTLY SATURDAY AND
SUNDAY...REMAINING TO OUR NW NEAR KY/TN...WHILE THE OFFSHORE UPPER
AND SURFACE LOWS SLOWLY DRIFT TO THE SOUTHWEST IN A CLOCKWISE
DIRECTION AROUND THE HIGH. MODELS APPEAR TO KEEP THE LOWS AND
ASSOCIATED MOISTURE/IMPACTS WELL TO OUR SE...AND GENERALLY
RESTRICT CONVECTION TO THE MOUNTAINS AND COAST SAT/SUN.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
GFS/ECMWF GENERALLY AGREE ON WEAKENING THE UPPER HIGH...AND
DEVELOPING WEAK TROUGHINESS OVER THE EASTERN CONUS...MONDAY THROUGH
WEDNESDAY. THEY ALSO SUGGEST A FRONTAL BOUNDARY TO APPROACH THE
REGION LATE TUESDAY INTO WEDNESDAY. AN ITEM OF UNCERTAINTY
INVOLVES WHAT HAPPENS TO THE UPPER/SURFACE LOWS OFFSHORE THE SE US
COAST...AND WHETHER ANY TROPICAL DEVELOPMENT/TRANSITION IS
POSSIBLE. ECMWF KEEPS THE LOW JUST OFFSHORE NE/EAST CENTRAL
FLORIDA...BEFORE KICKING OUT TO THE ENE AS THE UPPER HIGH WEAKENS
AND UPPER TROUGHINESS DEVELOPS AND APPROACHES FROM THE WEST. GFS
SPLITS THE UPPER ENERGY INTO TWO SEGMENTS...ONE THAT MOVES WEST
AND BRINGS THE SURFACE LOW WEST INTO NORTH FLORIDA/NE GOMEX AREA
MON/TUE. THE GFS SOLUTION RESULTS IN SOME MOISTURE INCREASE FOR
OUR FA LATE SUN INTO MON...WHILE THE ECMWF SOLUTION WOULD CONTINUE
TO KEEP OUR POPS MINIMAL FOR THAT TIME PERIOD. GENERALLY ACCEPTED
A BLEND OF ONGOING FORECAST AND LATEST GUIDANCE...PROVIDING SLIGHT
CHANCE POPS SUN AFTN THROUGH MON NT...WITH CHANCE POPS TUE AFTN
THROUGH WED WITH THE FRONT.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD EXCEPT POSSIBLE
MVFR VSBYS AT AGS/OGB THROUGH 13Z. RAP AND NAM BUFKIT INDICATING LOW
LEVEL MOISTURE COMBINED WITH A LOW LEVEL JET...WHICH COULD PRODUCE
MVFR CIGS THROUGH 13Z. CONFIDENCE IS LOW SINCE OTHER GUIDANCE NOT
SHOWING THIS.
SCATTERED CUMULUS CLOUDS EXPECTED WITH DAYTIME HEATING TODAY.
CANNOT RULE OUT ISOLATED CONVECTION NEAR OGB GIVEN MODERATE
INSTABILITY AND SEA BREEZE FRONT. HOWEVER...COVERAGE IS TOO LIMITED TO
INCLUDE IN TAF. WINDS WILL INCREASE FROM THE SOUTH SOUTHEAST 5 TO 10
MPH.
EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CONDITIONS POSSIBLE IN
FOG/STRATUS LATE TONIGHT INTO EARLY FRIDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
140 AM EDT THU MAY 24 2012
.SYNOPSIS...
UPPER LEVEL TROUGH OVER THE REGION WILL SLOWLY MOVE EASTWARD AND
EXIT THE REGION THURSDAY NIGHT. WEAK HIGH PRESSURE AND AN UPPER
LEVEL RIDGE WILL BUILD IN FOR FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /TONIGHT/...
UPPER LEVEL TROUGH REMAINS OVER THE REGION. LATEST SATELLITE
IMAGERY SHOWS THE CENTER OF THE UPPER CIRCULATION REMAINS IN NORTH
CAROLINA. STILL AN ISOLATED SHOWER/STORM POSSIBLE ACROSS THE
NORTHEASTERN PORTION OF THE CWA WHERE SEA-BREEZE AND OTHER
OUTFLOW BOUNDARIES HAVE KEPT A FEW SHOWERS GOING. ACTIVITY SHOULD
DIMINISH BY MIDNIGHT. ENTIRE AREA SHOULD BE DRY BY MIDNIGHT. LOW
TEMPERATURES IN THE MIDDLE 60S STILL LOOK OK.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
UPPER TROUGH FINALLY BEGINS TO MOVE EAST AND SHOULD EXIT THE AREA
THURSDAY NIGHT. WILL KEEP A 20 PERCENT CHANCE OF DIURNAL
CONVECTIVE ACTIVITY FOR THURSDAY AFTERNOON AND EVENING. AN UPPER
RIDGE WILL BUILD EAST OVER THE FORECAST AREA FRIDAY AND FRIDAY
NIGHT. DRY WEATHER IS EXPECTED FRIDAY AND FRIDAY NIGHT. HIGH
TEMPERATURES BOTH THURSDAY AND FRIDAY WILL BE IN THE UPPER 80S TO
AROUND 90. OVERNIGHT LOWS WILL BE IN THE MIDDLE TO UPPER 60S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
MEDIUM RANGE MODELS IN GOOD AGREEMENT INITIALLY FOR THE WEEKEND
SATURDAY AND SUNDAY WITH UPPER RIDGE CONTROLLING THE WEATHER.
DRY AND QUITE WARM CONDITIONS SATURDAY AND SUNDAY. HIGHS NEAR 90
TO THE LOWER 90S BOTH DAYS. LOWS SATURDAY NIGHT IN THE MIDDLE TO
UPPER 60S. SOME MODEL DIFFERENCES BY MONDAY AS TO WHEN UPPER RIDGE
SHOULD WEAKEN ALLOWING MORE MOISTURE INTO THE REGION. BOTH GFS AND
ECMWF SHOW A WEAK LOW PRESSURE OR TROUGH NEAR THE SOUTHEAST COAST
SPREADING SOME MOISTURE TO THE AREA. ECMWF HAS SURFACE LOW CLOSER
TO SOUTHEAST COAST ON MONDAY AND THEREFORE PULLS MOISTURE IN SOONER
THAN THE GFS. WILL INTRODUCE A SLIGHT CHANCE OF CONVECTIVE ACTIVITY
BY MONDAY AFTERNOON. THEN LIKE AT LEAST A SLIGHT CHANCE TUESDAY
AND WEDNESDAY WITH CONTINUED SOUTH TO SOUTHEAST LOW LEVEL WIND
FLOW ADVECTING MOISTURE TO THE REGION. SUMMER-LIKE TEMPERATURES
EXPECTED IN THE EXTENDED PERIOD WITH HIGHS IN THE UPPER 80S TO
LOWER 90S. OVERNIGHT LOWS MAINLY IN THE UPPER 60S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD EXCEPT POSSIBLE
MVFR VSBYS AT AGS/OGB THROUGH 13Z. RAP AND NAM BUFKIT INDICATING LOW
LEVEL MOISTURE COMBINED WITH A LOW LEVEL JET...WHICH COULD PRODUCE
MVFR CIGS THROUGH 13Z. CONFIDENCE IS LOW SINCE OTHER GUIDANCE NOT
SHOWING THIS.
SCATTERED CUMULUS CLOUDS EXPECTED WITH DAYTIME HEATING TODAY.
CANNOT RULE OUT ISOLATED CONVECTION NEAR OGB GIVEN MODERATE
INSTABILITY AND SEA BREEZE FRONT. HOWEVER...COVERAGE IS TOO LIMITED TO
INCLUDE IN TAF. WINDS WILL INCREASE FROM THE SOUTH SOUTHEAST 5 TO 10
MPH.
EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CONDITIONS POSSIBLE IN
FOG/STRATUS LATE TONIGHT INTO EARLY FRIDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
410 AM CDT THU MAY 24 2012
...UPDATED AND RESENT THE SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 408 AM CDT THU MAY 24 2012
THE SHORTER TERM MODELS OF THE NAM AND THE HRRR NOW SHOW THERE WILL
NOT BE ANY PRECIP IN OUR FORECAST AREA TODAY. THE COLD FRONT IS
THROUGH OUR CWA, WITH A LOW PRESSURE SYSTEM POSITIONED OVER
SOUTHEAST COLORADO. AN UPPER LEVEL DISTURBANCE IS MOVING
EAST-NORTHEAST BUT TRAVELING THROUGH AREAS NORTH OF OUR COUNTY
WARNING AREA, NORTHERN KANSAS AND NEBRASKA AND POINTS
NORTHEASTWARD. THERE IS SOME CIRRUS AROUND AND THINK THE GRIDS WILL
PRODUCE MOSTLY SUNNY CONDITIONS. WHEN THE FRONT FIRST WENT THROUGH,
THE WINDS BEHIND THE FRONT QUICKLY PICKED UP INTO ADVISORY LEVELS,
AND THUS A SHORT TERM WIND ADVISORY WAS ISSUED FOR THAT AREA WEST OF
A DIGHTON TO MONTEZUMA LINE, AND ALSO NORTH OF A JOHNSON CITY TO
MONTEZUMA LINE. AT THE TIME OF WRITING THIS SHORT TERM DISCUSSION,
WINDS HAD FALLEN BACK TO LESS THAN ADVISORY CRITERIA AT ALL SITES
EXCEPT HUGOTON AND SCOTT CITY. THIS WIND ADVISORY WILL EXPIRE AT
09Z, AND SHOULD NOT SHOW UP IN THE NEXT ZONE ISSUANCE. TEMPERATURES
TODAY WILL BE COOLER THAN YESTERDAY`S NEAR CENTURY MARKS, DUE TO THE
COLD FRONTAL PASSAGE AND HIGH CLOUDS. HIGHS TODAY SHOULD RANGE FROM
THE MID 80S ALONG THE OKLAHOMA PANHANDLE TO THE UPPER 70S NORTH OF
THE I-70 CORRIDOR.
THE COLD FRONT MENTIONED ABOVE WILL COME BACK NORTH TONIGHT AS A
WARM FRONT. JUST HOW FAST NORTH IT WILL MOVES IS HANDLED
DIFFERENTLY BY THE MODELS. THE NAM MODEL BRINGS THE FRONT NORTH THE
FASTEST, WITH THE GFS AND ECMWF MODELS SLOWER. BY THE TIME THE
FRONT REACHES OUR NORTHERN COUNTIES OF ELLIS, TREGO, RUSH, NESS,
LANE AND SCOTT BY 09Z, THERE COULD BE A FEW THUNDERSTORMS FORM IN
THE ELEVATED UNSTABLE LAYERS OF THE ATMOSPHERE. I ONLY PLACED 20
POPS IN, AS THE TIMING OF THE FRONT IS STILL IN QUESTION. CLOUDS
WILL BLANKET MOST OF SOUTHWESTERN KANSAS THURSDAY NIGHT, AND WINDS
NEAR THE OKLAHOMA BORDER WILL BE SOUTH AT 10 TO 20 MPH BEHIND THE
FRONT AND EASTERLY AT 10 TO 20 MPH NORTH OF THE FRONT. TEMPERATURES
THURSDAY NIGHT
WILL BE SOMEWHAT ELEVATED, ONLY FALLING TO THE MID 60S IN THE
MEDICINE LODGE AND PRATT AREAS, INTO THE LOWER 60S FROM LIBERAL TO
DODGE CITY TO LARNED, AND INTO THE MIDDLE 50S FROM SYRACUSE TO SCOTT
CITY TO WAKEENEY.
.LONG TERM...(FRIDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT THU
MAY 24 2012
A CHALLENGING FORECAST LIES AHEAD FOR THE COMING SEVERAL DAYS, AS A
FEW OPPORTUNITIES FOR CONVECTION APPEAR POSSIBLE. BY FRIDAY MORNING,
A WARM FRONT WILL BE LIFTING NORTHWARD THROUGH SOUTHWEST KANSAS. THE
MODELS DIFFER SIGNIFICANTLY WITH THIS FRONT. THE GFS PRODUCES QPF AS
EARLY AS OVERNIGHT THURSDAY HEADING INTO FRIDAY MORNING, AND REALLY
INCREASING THE QPF AROUND THE 12Z TIMEFRAME. BY CONTRAST THE NAM AND
ECMWF ARE MORE IN LINE WITH A DRY SOLUTION. THE CONVECTION PRODUCED
IN THESE CASES ARE MORE IN LINE WITH THE EDGE OF A CAPPING LATER IN
THE MID LEVELS THAT IS LOCATED ACROSS NORTHERN KANSAS. IN EITHER
CASE; STRONG LOW LEVEL THETA-E ADVECTION AND ISENTROPIC LIFT IN THE
MORNING, OR BREAKING THE CAP LATE IN THE DAY FARTHER NORTH, QUARTER
TO GOLFBALL SIZED HAIL WOULD BE LIKELY. HOWEVER, THE MOST LIKELY
EVENT IS PROBABLY ALONG THE LINES OF THE ECMWF AND NAM GIVEN THE
WARM TEMPERATURES IN THE MID LEVELS OF 13 TO 14 DEGREES C. IF THE
WARM AIR ALOFT IS STRONG ENOUGH OF A CAP ON FRIDAY, THE POTENTIAL
FOR SEVERE CONVECTION MIGHT BE RELEGATED EVEN FARTHER NORTH INTO
NORTH CENTRAL KANSAS AND NEBRASKA. SURFACE TEMPERATURES WILL EXCEED
95 DEGREES IN THIS WARM BOUNDARY LAYER AIR AND LIKELY HIT 100
DEGREES OR MORE IN THE RED HILLS REGION. IT IS UNKNOWN AT THIS TIME
IF THE SMOKE FROM THE NEW MEXICO FIRES WILL PLAY A ROLE IN
INHIBITING INSOLATION WHICH IN TURN COULD PREVENT TEMPERATURES FROM
REACHING THE AFOREMENTIONED VALUES. BUT IT IS SOMETHING TO CONSIDER
IN THE NEXT 24 OR SO HOURS.
HEADING INTO THE WEEKEND, A CONSENSUS OF THE MODELS WOULD SEEM TO
SUPPORT AT LEAST SOME POTENTIAL FOR DRYLINE TRIGGERED CONVECTION
ACROSS CENTRAL KANSAS ON SATURDAY. HOWEVER, IT IS NOT CLEAR AT ALL
JUST WHERE THE DRYLINE MIGHT BE LOCATED AT THIS TIME. GENERALLY
ISOLATED DISCREET CONVECTION WITHIN AMPLE SHEAR FOR AT LEAST THE
POTENTIAL FOR SUPERCELLS PRODUCING UP TO GOLFBALL SIZED HAIL.
A MORE ORGANIZED SEVERE CONVECTIVE POTENTIAL COULD OCCUR ON SUNDAY.
THE FORCING MECHANISMS FOR THIS POTENTIAL WILL BE AN ADVANCING UPPER
TROUGH WITH A LARGE COLD POOL (COOLING TEMPERATURES ALOFT) AND A
LEAD UPPER JET`S RIGHT REAR QUADRANT. THE GFS AND ECMWF BOTH APPEAR
TO SUPPORT A TORNADIC SUPERCELL ENVIRONMENT SUNDAY AFTERNOON ALONG
THE WARM FRONT-SURFACE LOW INTERSECTION.
BEYOND THIS PERIOD, THE FORECAST APPEARS TO CREATE MORE UNCERTAINTY.
THE OVERALL CONSENSUS APPEARS TO BE A FLATTENING OF THE UPPER FLOW
AS THE UPPER JET LIFTS INTO THE UPPER MIDWEST THROUGH TUESDAY. THIS
SHOULD, WITH TIME ALLOW DRIER AIR TO SETTLE OVER WESTERN KANSAS
REDUCING THE ODDS OF THUNDERSTORMS. BEFORE THE ECMWF AND GFS BOTH
TREND RAPIDLY TOWARD STRONG MOISTURE RETURN AND CONVECTION ONCE
AGAIN BY AROUND DAY 7.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 359 AM CDT THU MAY 24 2012
AS A FRONT MOVES ACROSS CENTRAL KANSAS, SOUTH WINDS WILL SHIFT TO
THE NORTH OR NORTHEAST AND GUST BRIEFLY INTO THE 25 TO 30 KNOT
RANGE. AFTER 09Z, EXPECT NORTHWEST WINDS IN THE 15 TO 20 KNOT
RANGE. AS HIGH PRESSURE SETTLES SOUTH INTO THE TAF AREAS THURSDAY
MORNING, WINDS WILL BECOME NORTHWEST AND WILL SUBSIDE TO AROUND 12
TO 13 KNOTS. THE ONLY CLOUDS EXPECTED ARE HIGH CIRRUS CLOUDS IN THE
150-200 THOUSAND FOOT RANGE, SO VFR CONDITIONS WILL PREVAIL
THROUGH THE 24 HOUR TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 83 62 97 70 / 0 10 10 10
GCK 82 60 96 68 / 0 10 10 10
EHA 85 59 96 66 / 0 10 10 10
LBL 85 62 100 68 / 0 10 10 10
HYS 80 59 86 69 / 10 10 20 20
P28 85 67 97 72 / 0 10 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
359 AM CDT THU MAY 24 2012
...UPDATED FOR THE SHORT TERM AND LONG TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 359 AM CDT THU MAY 24 2012
THE SHORTER TERM MODELS OF THE NAM AND THE HRRR NOW SHOW THERE WILL
NOT BE ANY PRECIP IN OUR FORECAST AREA TODAY. THE COLD FRONT IS
THROUGH OUR CWA, WITH A LOW PRESSURE SYSTEM POSITIONED OVER
SOUTHEAST COLORADO. AN UPPER LEVEL DISTURBANCE IS MOVING
EAST-NORTHEAST BUT TRAVELING THROUGH AREAS NORTH OF OUR COUNTY
WARNING AREA, NORTHERN KANSAS AND NEBRASKA AND POINTS
NORTHEASTWARD. THERE IS SOME CIRRUS AROUND AND THINK THE GRIDS WILL
PRODUCE MOSTLY SUNNY CONDITIONS. WHEN THE FRONT FIRST WENT THROUGH,
THE WINDS BEHIND THE FRONT QUICKLY PICKED UP INTO ADVISORY LEVELS,
AND THUS A SHORT TERM WIND ADVISORY WAS ISSUED FOR THAT AREA WEST OF
A DIGHTON TO MONTEZUMA LINE, AND ALSO NORTH OF A JOHNSON CITY TO
MONTEZUMA LINE. AT THE TIME OF WRITING THIS SHORT TERM DISCUSSION,
WINDS HAD FALLEN BACK TO LESS THAN ADVISORY CRITERIA AT ALL SITES
EXCEPT HUGOTON AND SCOTT CITY. THIS WIND ADVISORY WILL EXPIRE AT
09Z, AND SHOULD NOT SHOW UP IN THE NEXT ZONE ISSUANCE. TEMPERATURES
TODAY WILL BE COOLER THAN YESTERDAY`S NEAR CENTURY MARKS, DUE TO THE
COLD FRONTAL PASSAGE AND HIGH CLOUDS. HIGHS TODAY SHOULD RANGE FROM
THE MID 80S ALONG THE OKLAHOMA PANHANDLE TO THE UPPER 70S NORTH OF
THE I-70 CORRIDOR.
THE COLD FRONT MENTIONED ABOVE WILL COME BACK NORTH TONIGHT AS A
WARM FRONT. JUST HOW FAST NORTH IT WILL MOVES IS HANDLED
DIFFERENTLY BY THE MODELS. THE NAM MODEL BRINGS THE FRONT NORTH THE
FASTEST, WITH THE GFS AND ECMWF MODELS SLOWER. BY THE TIME THE
FRONT REACHES OUR NORTHERN COUNTIES OF ELLIS, TREGO, RUSH, NESS,
LANE AND SCOTT BY 09Z, THERE COULD BE A FEW THUNDERSTORMS FORM IN
THE ELEVATED UNSTABLE LAYERS OF THE ATMOSPHERE. I ONLY PLACED 20
POPS IN, AS THE TIMING OF THE FRONT IS STILL IN QUESTION. CLOUDS
WILL BLANKET MOST OF SOUTHWESTERN KANSAS THURSDAY NIGHT, AND WINDS
NEAR THE OKLAHOMA BORDER WILL BE SOUTH AT 10 TO 20 MPH BEHIND THE
FRONT AND EASTERLY AT 10 TO 20 MPH NORTH OF THE FRONT. TEMPERATURES
THURSDAY NIGHT
WILL BE SOMEWHAT ELEVATED, ONLY FALLING TO THE MID 60S IN THE
MEDICINE LODGE AND PRATT AREAS, INTO THE LOWER 60S FROM LIBERAL TO
DODGE CITY TO LARNED, AND INTO THE MIDDLE 50S FROM SYRACUSE TO SCOTT
CITY TO WAKEENEY.
.LONG TERM...(FRIDAY THROUGH THURSDAY)
ISSUED AT 359 AM CDT THU MAY 24 2012
A CHALLENGING FORECAST LIES AHEAD FOR THE COMING SEVERAL DAYS, AS A
FEW OPPORTUNITIES FOR CONVECTION APPEAR POSSIBLE. BY FRIDAY MORNING,
A WARM FRONT WILL BE LIFTING NORTHWARD THROUGH SOUTHWEST KANSAS. THE
MODELS DIFFER SIGNIFICANTLY WITH THIS FRONT. THE GFS PRODUCES QPF AS
EARLY AS OVERNIGHT THURSDAY HEADING INTO FRIDAY MORNING, AND REALLY
INCREASING THE QPF AROUND THE 12Z TIMEFRAME. BY CONTRAST THE NAM AND
ECMWF ARE MORE IN LINE WITH A DRY SOLUTION. THE CONVECTION PRODUCED
IN THESE CASES ARE MORE IN LINE WITH THE EDGE OF A CAPPING LATER IN
THE MID LEVELS THAT IS LOCATED ACROSS NORTHERN KANSAS. IN EITHER
CASE; STRONG LOW LEVEL THETA-E ADVECTION AND ISENTROPIC LIFT IN THE
MORNING, OR BREAKING THE CAP LATE IN THE DAY FARTHER NORTH, QUARTER
TO GOLFBALL SIZED HAIL WOULD BE LIKELY. HOWEVER, THE MOST LIKELY
EVENT IS PROBABLY ALONG THE LINES OF THE ECMWF AND NAM GIVEN THE
WARM TEMPERATURES IN THE MID LEVELS OF 13 TO 14 DEGREES C. IF THE
WARM AIR ALOFT IS STRONG ENOUGH OF A CAP ON FRIDAY, THE POTENTIAL
FOR SEVERE CONVECTION MIGHT BE RELEGATED EVEN FARTHER NORTH INTO
NORTH CENTRAL KANSAS AND NEBRASKA. SURFACE TEMPERATURES WILL EXCEED
95 DEGREES IN THIS WARM BOUNDARY LAYER AIR AND LIKELY HIT 100
DEGREES OR MORE IN THE RED HILLS REGION. IT IS UNKNOWN AT THIS TIME
IF THE SMOKE FROM THE NEW MEXICO FIRES WILL PLAY A ROLE IN
INHIBITING INSOLATION WHICH IN TURN COULD PREVENT TEMPERATURES FROM
REACHING THE AFOREMENTIONED VALUES. BUT IT IS SOMETHING TO CONSIDER
IN THE NEXT 24 OR SO HOURS.
HEADING INTO THE WEEKEND, A CONSENSUS OF THE MODELS WOULD SEEM TO
SUPPORT AT LEAST SOME POTENTIAL FOR DRYLINE TRIGGERED CONVECTION
ACROSS CENTRAL KANSAS ON SATURDAY. HOWEVER, IT IS NOT CLEAR AT ALL
JUST WHERE THE DRYLINE MIGHT BE LOCATED AT THIS TIME. GENERALLY
ISOLATED DISCREET CONVECTION WITHIN AMPLE SHEAR FOR AT LEAST THE
POTENTIAL FOR SUPERCELLS PRODUCING UP TO GOLFBALL SIZED HAIL.
A MORE ORGANIZED SEVERE CONVECTIVE POTENTIAL COULD OCCUR ON SUNDAY.
THE FORCING MECHANISMS FOR THIS POTENTIAL WILL BE AN ADVANCING UPPER
TROUGH WITH A LARGE COLD POOL (COOLING TEMPERATURES ALOFT) AND A
LEAD UPPER JET`S RIGHT REAR QUADRANT. THE GFS AND ECMWF BOTH APPEAR
TO SUPPORT A TORNADIC SUPERCELL ENVIRONMENT SUNDAY AFTERNOON ALONG
THE WARM FRONT-SURFACE LOW INTERSECTION.
BEYOND THIS PERIOD, THE FORECAST APPEARS TO CREATE MORE UNCERTAINTY.
THE OVERALL CONSENSUS APPEARS TO BE A FLATTENING OF THE UPPER FLOW
AS THE UPPER JET LIFTS INTO THE UPPER MIDWEST THROUGH TUESDAY. THIS
SHOULD, WITH TIME ALLOW DRIER AIR TO SETTLE OVER WESTERN KANSAS
REDUCING THE ODDS OF THUNDERSTORMS. BEFORE THE ECMWF AND GFS BOTH
TREND RAPIDLY TOWARD STRONG MOISTURE RETURN AND CONVECTION ONCE
AGAIN BY AROUND DAY 7.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 359 AM CDT THU MAY 24 2012
AS A FRONT MOVES ACROSS CENTRAL KANSAS, SOUTH WINDS WILL SHIFT TO
THE NORTH OR NORTHEAST AND GUST BRIEFLY INTO THE 25 TO 30 KNOT
RANGE. AFTER 09Z, EXPECT NORTHWEST WINDS IN THE 15 TO 20 KNOT
RANGE. AS HIGH PRESSURE SETTLES SOUTH INTO THE TAF AREAS THURSDAY
MORNING, WINDS WILL BECOME NORTHWEST AND WILL SUBSIDE TO AROUND 12
TO 13 KNOTS. THE ONLY CLOUDS EXPECTED ARE HIGH CIRRUS CLOUDS IN THE
150-200 THOUSAND FOOT RANGE, SO VFR CONDITIONS WILL PREVAIL
THROUGH THE 24 HOUR TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 97 70 97 / 10 10 10 20
GCK 60 96 68 95 / 10 10 10 20
EHA 59 96 66 95 / 10 10 10 20
LBL 62 100 68 96 / 10 10 10 20
HYS 59 86 69 97 / 10 20 20 10
P28 67 97 72 97 / 10 20 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1237 AM MDT THU MAY 24 2012
.UPDATE...
ISSUED AT 1236 AM MDT THU MAY 24 2012
UPDATED GRIDS AND ZONES FOR THE CANCELLATION OF SEVERE
THUNDERSTORM WATCH 294. OTHERWISE NO OTHER CHANGES.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TONIGHT)
ISSUED AT 1245 PM MDT WED MAY 23 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
ACROSS THE NORTHERN ROCKIES...WITH WEST/SOUTHWEST FLOW ACROSS THE
INTER-MOUNTAIN WEST INTO THE CENTRAL HIGH PLAINS. AT THE SURFACE A COLD
FRONT HAS STALLED OVER WESTERN KANSAS...CURRENTLY ACROSS THE EASTERN
PART OF THE CWA.
A SHORTWAVE TROUGH CURRENTLY OVER THE GREAT BASIN WILL MOVE
EAST-NORTHEAST ACROSS NORTH CENTRAL COLORADO AND SOUTHWEST NEBRASKA
TONIGHT. SHOWERS/THUNDERSTORMS HAVE ALREADY DEVELOPED AHEAD OF THIS
FEATURE ALONG THE FRONT RANGE INTO SOUTHEASTERN WYOMING. THIS
ACTIVITY WILL SPREAD SOUTH AND EAST OVER OUR CWA LATER THIS
AFTERNOON...WITH COVERAGE INCREASING ACROSS THE NORTHERN PART OF OUR
FORECAST AREA THROUGH 06Z. CONVERGENCE ZONE ALONG AND NORTH OF
STALLED FRONT COULD ACT AS A FOCUS FOR EARLIER THUNDERSTORM
INITIATION LATER THIS AFTERNOON AND EVENING...HOWEVER THIS IS
REMOVED FROM LARGE SCALE ASCENT ASSOCIATED WITH SHORTWAVE SO
COVERAGE SHOULD BE LIMITED ACROSS THE SOUTH. VERY STRONG SHEAR IS
PRESENT ACROSS THE CWA...WITH INSTABILITY DECREASING THE FURTHER
NORTH IN THE CWA WHERE TD VALUES IN THE 30-40F RANGE HAVE ADVECTED
IN BEHIND THE FRONT. SEVERE CONVECTION SHOULD BE LIMITED TO THE I-70
CORRIDOR THROUGH EARLY EVENING WHERE THE BEST OVERLAP BETWEEN
SHEAR/INSTABILITY IS EXPECTED. LATER TONIGHT ELEVATED INSTABILITY
COULD COMBINE WITH STRONG UPPER LEVEL DYNAMICS ASSOCIATED WITH THE
SHORTWAVE ACROSS SOUTHWEST NEBRASKA TO BRING ADDITIONAL SEVERE
CHANCES. SUBSIDENCE QUICKLY BUILDS IN BEHIND DEPARTING SHORTWAVE
TROUGH AFTER 06Z...WITH COVERAGE DECREASING FROM THE SOUTHWEST TO
THE NORTHEAST THROUGH SUNRISE THURSDAY.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 224 PM MDT WED MAY 23 2012
THURSDAY-THURSDAY NIGHT...PV ANOMALY WILL LIFT TO THE NORTH AND EAST
OF THE AREA FAIRLY QUICKLY DURING THE MORNING HOURS...WITH MID LEVEL
FRONTOGENESIS QUICKLY DIMINISHING AND DEEP LAYER DIV Q FIELDS
INDICATE FAIRLY STRONG LARGE SCALE FORCING FOR SUBSIDENCE OVER THE
AREA. STILL HAVE A FEW TIMING CONCERNS THOUGH...AND THINK HOLDING
ONTO SOME SMALL POPS WARRANTED FOR AT LEAST THE FIRST FEW HOURS OF
THE PERIOD. SOUNDINGS SUGGEST THAT WEAK INSTABILITY WILL LINGER
ACROSS MUCH OF THE AREA THROUGH THE DAY...AS DIFFERENTIAL TEMP
ADVECTION SHOULD LEAD TO THE DEVELOPMENT OF SHALLOW SFC BASED
INSTABILITY WITH EQUILIBRIUM LEVELS LESS THAN H5 AT MANY LOCATIONS.
ALTHOUGH SUBSIDENCE DIMINISHES IN THE AFTERNOON ACROSS SOUTHERN HALF
OF CWA...THINKING ANY AFTERNOON SHOWERS WILL BE STRONGLY DIURNALLY
DRIVEN AND THINK OVERALL COVERAGE WILL BE FAIRLY LOW THROUGH THE
EARLY EVENING. LARGE SCALE ASCENT WILL ONCE AGAIN WITH STRONG LOW
LEVEL WAA DEVELOPING IN RESPONSE TO H3 JET STREAK LIFTING NORTH INTO
SOUTHERN SOUTH DAKOTA. SEEMS LIKE RECENT SUITE OF MODELS NOT ALL
THAT OPTIMISTIC ABOUT BREAKING OUT PRECIPITATION OVERNIGHT...BUT
GIVEN STRONG AND PERSISTENT WAA/ISENTROPIC FORCING STRONG MOISTURE
TRANSPORT ABOVE THE SFC...AND SMALL CONDENSATION PRESSURE DEFICITS
IN AREA OF NEGATIVE THETA E LAPSE RATES...THINK THE THREAT FOR
SHOWERS AND STORMS WILL BE THERE DESPITE CURRENT MODEL QPF OUTPUT.
FRIDAY-SATURDAY...WARM FRONT WILL SLOWLY LIFT TO THE NORTH THROUGH
THE PERIOD AND WILL NOT ONLY PLAY A BIG ROLE ON POTENTIAL FOR
THUNDERSTORMS...IT WILL ALSO HAVE A LARGE ROLE IN TEMPERATURE
FORECAST AS POSSIBILITY EXISTS FOR A PRETTY SHARP GRADIENT WITH
TEMPS ON FRIDAY. SREF PLUME DATA INDICATING NEARLY A 20 DEGREE
SPREAD IN TEMPS FOR MOST LOCATIONS...WITH ABOUT EQUAL CLUSTERING ON
EITHER SIDE...MAINLY ON FRIDAY. PLAN ON KEEPING NEAR MEAN VALUES FOR
FRIDAY...ALTHOUGH THERE IS MUCH MORE AGREEMENT ON VERY WARM TEMPS ON
SATURDAY AND HAVE WARMED TEMPS ACCORDINGLY.
GIVEN EXPECTED PRESSURE FALL PATTERN AROUND AREA AND LARGE SCALE
FORCING FOR ASCENT BECOMING MAXIMIZED WELL TO THE WEST OF THE
AREA...DO NOT ANTICIPATE MUCH OF A NORTHERN MOVEMENT OF THE
FRONT...WITH BULK OF CWA REMAINING CLOUDY AND COOL THROUGH THE DAY.
THINK THUNDERSTORMS WILL LIKELY BE ONGOING THROUGH THE MORNING HOURS
AS PREVIOUSLY MENTIONED WAA PATTERN REMAINS IN PLACE THROUGH THE
MORNING HOURS...BEFORE LARGE SUBSIDENCE INVERSION STRENGTHENS DURING
THE AFTERNOON SHARPLY INCREASING CINH PROFILES AND ADVECTING MUCH
DRIER AIR INTO THE AREA. MODELS CONTINUE TO PRODUCE LIGHT
PRECIPITATION AFTER THIS POINT...BUT SOUNDINGS LOOK LIKE ANY
PRECIPITATION PROCESSES IN THE LATE AFTERNOON OR EVENING LOOK TO BE
VERY SHALLOW/DRIZZLE TYPE PROCESSES AND DO NOT PLAN ON GOING ALONG
WITH HIGHER GUIDANCE POPS AT THIS TIME. APPEARS TO BE LOTS OF
INSTABILITY DURING THE LATE AFTERNOON AND EVENING ALONG/NORTH OF
FRONT...BUT CINH LOOKS VERY STRONG AND GIVEN RIDGING ALOFT DO NOT
THINK THIS WILL BE OVERCOME.
ON SATURDAY...EXPECT WINDY TO VERY WINDY CONDITIONS TO DEVELOP
ACROSS MUCH OF THE AREA DURING THE AFTERNOON WITH STRONGEST WINDS
BEHIND DRYLINE IN EASTERN COLORADO...WHERE DEEP MIXED LAYER SHOULD
TAP INTO STRONG FLOW ALOFT. WITH TEMPS IN THE 90S...WIND GUSTS
APPROACHING 50 KTS AND MIXED TDS SUGGESTING A RAPID DROP OFF IN
DEWPOINTS...POTENTIAL EXISTS FOR EXTREMELY CRITICAL FIRE WX
CONDITIONS TO DEVELOP. IT IS A BIT TOO FAR IN THE FUTURE TO ISSUE
ANY HIGHLIGHTS AT THIS POINT...BUT POTENTIAL FOR FIRE WEATHER AND
SIGNIFICANT WINDS IS INCREASING. OTHERWISE...WARM FRONT WILL LIFT TO
THE NORTH OUT OF THE AREA DURING THE MORNING HOURS WITH ANY
POTENTIAL FOR AFTERNOON THUNDERSTORMS ALONG DRYLINE DURING THE LATE
AFTERNOON. WITH DEEP MIXING AND BULK OF PRESSURE FALLS TO THE NORTH
OF THE AREA...WOULD EXPECT DRYLINE TO MIX EASTWARD WITH BULK OF CWA
IN DRY SECTOR. ENOUGH SPREAD EXISTS TO WARRANT A MORE BROAD BRUSHED
APPROACH TO CHANCES ATTM THOUGH AND WITH STRONG FLOW ALOFT THERE
WILL BE POTENTIAL FOR AT LEAST A FEW STRONG/SEVERE HIGH BASED STORMS
IN THE AFTERNOON.
IN THE EXTENDED (SAT NIGHT-WEDNESDAY)...ACTIVE WEATHER PATTERN
EXPECTED THROUGH THE PERIOD AS MEDIUM RANGE MODELS SHOWING
REASONABLE AGREEMENT IN DEVELOPMENT OF STRONG TROUGH/AMPLIFIED
PATTERN ACROSS THE PLAINS THROUGH THE WEEKEND...FOLLOWED BY MORE
ZONAL FLOW ALOFT DURING THE BEGINNING OF THE WEEK. WHILE 06Z GEFS
DATA SHOWS A RELATIVELY CONSISTENT PATTERN WITH LARGE TROUGH
IMPACTING THE AREA DURING THE WEEKEND...MODEL SPREAD/UNCERTAINTY
INCREASES DURING THE LATER HALF AS THERE APPEARS TO BE A DECENT
AMOUNT OF DISCREPANCY WITH SMALL SCALE FEATURES. BEST CHANCE FOR
PRECIPITATION WILL LIKELY BE ON SUNDAY AFTERNOON AS COLD FRONT
SLOWLY MOVES ACROSS THE AREA PROVIDING AMPLE FORCING TO FOCUS
THUNDERSTORM DEVELOPMENT. WITH LIGHT EASTERLY/UPSLOPE FLOW AND
SEVERAL FAST MOVING SHORT WAVE TROUGHS MOVING THROUGH ZONAL
FLOW...PRECIP CHANCES WILL CONTINUE THROUGH THE MIDDLE OF THE WEEK.
ASIDE FROM TIMING WITH FROPA ON SUNDAY BRINGING THE POTENTIAL FOR
ONE MORE VERY WARM DAY...LOOKS LIKE COOLER CONDITIONS WILL PREVAIL
THROUGH THE START OF THE WEEK AS LIGHT EASTERLY FLOW WILL PREVAIL
BEHIND COLD FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1117 PM MDT WED MAY 23 2012
SHOWERS AND THUNDERSTORMS WILL CONTINUE OVERNIGHT AT BOTH KGLD AND
KMCK. DO NOT EXPECT CONDITIONS TO DETERIORATE BELOW VFR BUT CANNOT
RULE OUT A BRIEF PERIOD OF MVFR NEAR A STRONG THUNDERSTORM. THE
SHORTWAVE SHOULD EXIT BY SUNRISE. BROKEN TO SCATTERED MID LEVEL
CLOUDS WILL PASS OVER THE REGION THURSDAY. CLOUDS WILL INCREASE
AGAIN FRIDAY EVENING WITH A SLIGHT CHANCE OF SOME SHOWERS.
&&
.FIRE WEATHER...
ISSUED AT 224 PM MDT WED MAY 23 2012
VERY WINDY CONDITIONS...WITH GUSTS IN EXCESS OF 50 MPH
POSSIBLE...ARE EXPECTED ACROSS A LARGE PORTION OF THE AREA ON
SATURDAY. AFTERNOON HUMIDITIES WILL FALL TO AROUND 10 PERCENT
ACROSS PORTIONS OF EASTERN COLORADO AND ADJACENT AREAS DURING THE
AFTERNOON AS THE WINDS INCREASE. THE COMBINATION OF VERY DRY AND
VERY WINDY CONDITIONS WILL BRING THE POTENTIAL FOR EXTREMELY
CRITICAL CONDITIONS ON SATURDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...FS
SHORT TERM...DR
LONG TERM...JRM
AVIATION...FS
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION...CORRECTED
NWS DODGE CITY KS
1255 AM CDT THU MAY 24 2012
...UPDATED FOR THE 06Z AVIATION TAFS AND DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 142 PM CDT WED MAY 23 2012
NAM, RAP, AND HRRR WERE IN DECENT AGREEMENT WITH COLD FRONT
EXTENDING FROM NORTH CENTRAL KANSAS INTO EXTREME SOUTHWEST KANSAS
LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS FRONT WILL BE
LOCATED UNDER +14C TO +16C 700MB TEMPERATURES. IN ADDITION THE
BETTER LOW LEVEL MOISTURE IS STILL FORECAST TO BE LOCATED ACROSS
CENTRAL KANSAS AND FROM NORTHWEST KANSAS INTO SOUTH CENTRAL
NEBRASKA. BASED ON MODEL SOUNDINGS THE WARM MID LEVEL TEMPERATURES
LATE TODAY/EARLY TONIGHT APPEARS TO SERVE AS A CAP ACROSS MOST OF
SOUTHWEST KANSAS. THE POSSIBLE EXCEPTION WILL BE NEAR AND NORTH OF
INTERSTATE 70 IN NORTH CENTRAL KANSAS WERE BETTER LOW LEVEL
FRONTOGENESIS AND MOISTURE WILL BE PRESENT. IN ADDITION THIS WILL
BE NEAR THE NORTHERN EDGE OF THE WARM MID LEVEL TEMPERATURES. THE
NAM EVEN SUGGESTS SOME COOLING OCCURRING IN THE MID LEVEL AFTER
21Z ALONG AND NORTH OF INTERSTATE 70. GIVEN THE COOLER MID LEVEL
TEMPERATURES, BETTER LOW LEVEL MOISTURE/FRONTOGENESIS NEAR THE
SURFACE BOUNDARY, AND CAPES EARLY TONIGHT GREATER THAN 1000 J/KG
WILL GO AHEAD AND KEEP A MENTION OF THUNDERSTORMS NEAR THE SURFACE
BOUNDARY. ALSO BASED ON 0-6KM SHEAR FORECAST TO BE AROUND 50
KNOTS ALONG WITH 1000-2000 J/KG THERE WILL BE A CHANCE FOR ANY
STORM THAT DOES DEVELOP TO BECOME SEVERE. MAIN HAZARD STILL
APPEARS TO BE HAIL UP TO HALF DOLLAR SIZE AND WINDS UP TO 60 MPH.
FURTHER WEST...THE CONVECTION DEVELOPING ACROSS NORTHEAST COLORADO IS
EXPECTED TO SPREAD EAST EARLY TONIGHT BUT STAY NORTH OF THE
INTERSTATE 70 DURING THE OVERNIGHT HOURS. THE COLD POOL THAT IS
FORECAST TO DEVELOP WITH THESE STORMS OVERNIGHT SHOULD PUSH THE
COLD FRONT SOUTH ACROSS ALL OF SOUTHWEST KANSAS AFTER MIDNIGHT. BY
EARLY THURSDAY MORNING THIS COLD FRONT IS EXPECTED TO BE LOCATED
ACROSS CENTRAL KANSAS AND NORTHERN OKLAHOMA. BOUNDARY LAYER WINDS
BEHIND THIS FRONT ARE FORECAST TO RANGE FROM 30 TO 35 KNOTS AND
GIVEN THE TIGHT PRESSURE GRADIENT BEHIND THIS FRONT THE SURFACE WINDS
MAY APPROACH ADVISORY CRITERIA FOR A FEW HOURS FOLLOWING THE
FRONTAL PASSAGE LATE TONIGHT. AT THIS TIME HAVE DECIDED TO KEEP
SUSTAINED WINDS JUST BELOW ADVISORY CRITERIA FOR A FEW HOURS
BEHIND THIS FRONT. IN ADDITION TO THE WINDS SOME LOW LEVEL
MOISTURE WILL RETURN TO NORTH CENTRAL AND SOUTHWEST KANSAS. THE
WRF AND NMM EVEN SUGGESTS SOME LIGHT PRECIPITATION WILL BE
POSSIBLE AS THE LOWER LEVELS SATURATES. AT THIS TIME GIVEN THE ISENTROPIC
DOWNGLIDE PRESENT AND DEPTH OF THE MOIST LAYER LESS THAN 3000 FEET
AM TRENDING AWAY FROM INSERTING PRECIPITATION CHANCES AFTER
MIDNIGHT.
ON THURSDAY THE GUSTY NORTHWEST WINDS WILL GRADUALLY SUBSIDE BY
MID MORNING AS THE COLD FRONT CONTINUES TO MOVE SOUTHEAST ACROSS
EASTERN KANSAS AND OKLAHOMA. IN SOUTHEAST COLORADO THIS FRONT IS
EXPECTED TO BECOME NEARLY STATIONARY DURING THE DAY WITH SOME
ISENTROPIC LIFT/WARM AIR ADVECTION DEVELOPING NORTH OF THIS
BOUNDARY BY LATE DAY. THIS MAY BRING AN INCREASE IN MID LEVEL CLOUD
COVER LATE DAY TO PORTIONS OF SOUTHWEST KANSAS BASED ON I310 AND
I315 ISENTROPIC SURFACES AND 12Z BUFR SOUNDINGS. GIVEN SOME
INCREASING CLOUDS LATE DAY AND 850MB TEMPERATURES AT 00Z FRIDAY
WILL TREND TOWARDS THE COOLER GUIDANCE IN FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WHILE FURTHER NORTH HAVE KEPT HIGHS
CLOSER TO THE WARMER 850MB MIX DOWN TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 234 PM CDT WED MAY 23 2012
THURSDAY NIGHT:
NOT THAT IMPRESSED FOR PROSPECTS OF CONVECTION THURSDAY EVENING. SOME
ISENTROPIC LIFT IS EXPECTED ALONG THE 700 HPA BAROCLINIC BOUNDARY ACROSS
CENTRAL KANSAS. FORECAST SOUNDINGS FROM THE ECMWF/GFS SHOW THAT THERE
MAY BE SOME MID LEVEL CLOUDS, HOWEVER, THE OVERALL PROFILE IS FAIRLY
DRY AND CAPPED. WENT AHEAD AND THREW IN SOME SILENT POPS ACROSS MY NORTHERN
COUNTIES BUT DISCOUNTED THE WETTER GFS SOLUTION WHICH CONTINUES TO SUFFER
FROM OVERALL POOR SYNOPTIC PERFORMANCE. THE 4 KM NAM & ARW/NMM CORES
AREN`T TOO CONVINCING EITHER.
FRIDAY:
THE WARM SECTOR WILL CONTINUE TO SPREAD NORTHWARD DOWNSTREAM OF A SLOWLY
PROPAGATING 500 HPA TROUGH FURTHER WEST. TEMPERATURES WARM TO 33 DEG
C @ 850 HPA AND 15 DEG C & 700 HPA WITH A WELL MIXED ATMOSPHERE. HAVE
WARMED TEMPERATURES TO THE MID TO UPPER 90S DEG F ACROSS THE CENTRAL
AND SOUTHERN ZONES AS A RESULT. THE ECMWF IS VERY WARM WITH 102 DEG
F FOR DODGE CITY FRIDAY. WILL CONTINUE TO THE TREND UPWARD BUT NOT YET
BITE ON THE EXTREME. THERE COULD BE SOME CONVECTION EAST OF THE DRYLINE
FRIDAY EVENING BUT WITH SUCH WARM TEMPERATURES AT 700 HPA, WILL NOT
GO HIGHER THAN SLIGHT GIVEN THE VERY STOUT EML. ECMWF SHOWS ABOUT 2500
J/KG OF SBCAPE AND 30 TO 40 KT OF SHEAR SO WILL HAVE TO WATCH OUT
FOR SEVERE IN LATER FORECASTS.
SATURDAY:
AMPLIFICATION OF THE WESTERN TROUGH IS EXPECTED SATURDAY. THE 12Z ECMWF
IS LESS AGGRESSIVE WITH CONVECTION FOR SATURDAY EVENING ACROSS THE WEST
THAN COMPARED TO THE 00Z RUN. THIS IS PROBABLY DUE TO THE CONTINUED
STRONG EML FORECAST BY THE MODEL. WILL NOT GO HIGHER THAN SLIGHT POPS
IN THE MEANTIME. NOT MUCH UPPER LEVEL SUPPORT AS THE MAIN 250 HPA JET
AXIS IS STILL PRETTY FAR WEST. WILL CONTINUE HOT TEMPERATURES IN THE
GRIDS WITH MID TO UPPER 90S DEG F EXPECTED ACROSS MUCH OF THE REGION.
SUNDAY AND BEYOND:
CONVECTIVE PROSPECTS ARE BETTER SUNDAY AS THE RIGHT ENTRANCE REGION
OF THE AFOREMENTIONED 250 HPA TRAVERSES ACROSS NW KANSAS. CAA ASSOCIATED
WITH THE TROUGH AND LOW TO MID LEVEL COLD POOLS WILL ALLOW FOR A WEAKENING
OF THE EML. THE BEST CHANCE FOR CONVECTION APPEARS TO BE ACROSS CENTRAL
AND SOUTH CENTRAL KANSAS ALONG AND EASTWARD MIXING DRYLINE. THE
THERMODYNAMIC AND KINEMATIC PROFILES ARE SUPPORTIVE OF SEVERE WEATHER.
UL FLOW FLATTENS MONDAY AND TUESDAY AS THE ASSOCIATED TROUGH MOVES ACROSS
THE CANADIAN PRAIRIES. THIS WILL ALLOW FOR MORE SEASONAL YET ABOVE NORMAL
TEMPERATURES ACROSS SW KANSAS. WILL HAVE TO WATCH THE MIDWEEK PERIOD
NEXT WEEK AS IT TRANSITIONS INTO MORE OF A MCS PATTERN. DEWPOINTS/MOISTURE
COULD BE AN ISSUE THOUGH. HAVE GONE WITH A CLEANED UP VERSION OF ALLBLEND
POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1233 AM CDT THU MAY 24 2012
AS A FRONT MOVES ACROSS CENTRAL KANSAS, SOUTH WINDS WILL SHIFT TO
THE NORTH OR NORTHEAST AND GUST BRIEFLY INTO THE 25 TO 30 KNOT
RANGE. AFTER 09Z, EXPECT NORTHWEST WINDS IN THE 15 TO 20 KNOT
RANGE. AS HIGH PRESSURE SETTLES SOUTH INTO THE TAF AREAS THURSDAY
MORNING, WINDS WILL BECOME NORTHWEST AND WILL SUBSIDE TO AROUND 12
TO 13 KNOTS. THE ONLY CLOUDS EXPECTED ARE HIGH CIRRUS CLOUDS IN THE
150-200 THOUSAND FOOT RANGE, SO VFR CONDITIONS WILL PREVAIL
THROUGH THE 24 HOUR TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 97 70 97 / 10 10 10 20
GCK 60 96 68 95 / 10 10 10 20
EHA 59 96 66 95 / 10 10 10 20
LBL 62 100 68 96 / 10 10 10 20
HYS 59 86 69 97 / 10 20 20 10
P28 67 97 72 97 / 10 20 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 AM CDT /3 AM MDT/ EARLY THIS MORNING FOR
KSZ043-044-061>063-074>077.
&&
$$
SHORT TERM...BURGERT
LONG TERM...SUGDEN
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1240 AM CDT THU MAY 24 2012
...UPDATED FOR THE 06Z AVIATION TAFS AND DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 142 PM CDT WED MAY 23 2012
NAM, RAP, AND HRRR WERE IN DECENT AGREEMENT WITH COLD FRONT
EXTENDING FROM NORTH CENTRAL KANSAS INTO EXTREME SOUTHWEST KANSAS
LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS FRONT WILL BE
LOCATED UNDER +14C TO +16C 700MB TEMPERATURES. IN ADDITION THE
BETTER LOW LEVEL MOISTURE IS STILL FORECAST TO BE LOCATED ACROSS
CENTRAL KANSAS AND FROM NORTHWEST KANSAS INTO SOUTH CENTRAL
NEBRASKA. BASED ON MODEL SOUNDINGS THE WARM MID LEVEL TEMPERATURES
LATE TODAY/EARLY TONIGHT APPEARS TO SERVE AS A CAP ACROSS MOST OF
SOUTHWEST KANSAS. THE POSSIBLE EXCEPTION WILL BE NEAR AND NORTH OF
INTERSTATE 70 IN NORTH CENTRAL KANSAS WERE BETTER LOW LEVEL
FRONTOGENESIS AND MOISTURE WILL BE PRESENT. IN ADDITION THIS WILL
BE NEAR THE NORTHERN EDGE OF THE WARM MID LEVEL TEMPERATURES. THE
NAM EVEN SUGGESTS SOME COOLING OCCURRING IN THE MID LEVEL AFTER
21Z ALONG AND NORTH OF INTERSTATE 70. GIVEN THE COOLER MID LEVEL
TEMPERATURES, BETTER LOW LEVEL MOISTURE/FRONTOGENESIS NEAR THE
SURFACE BOUNDARY, AND CAPES EARLY TONIGHT GREATER THAN 1000 J/KG
WILL GO AHEAD AND KEEP A MENTION OF THUNDERSTORMS NEAR THE SURFACE
BOUNDARY. ALSO BASED ON 0-6KM SHEAR FORECAST TO BE AROUND 50
KNOTS ALONG WITH 1000-2000 J/KG THERE WILL BE A CHANCE FOR ANY
STORM THAT DOES DEVELOP TO BECOME SEVERE. MAIN HAZARD STILL
APPEARS TO BE HAIL UP TO HALF DOLLAR SIZE AND WINDS UP TO 60 MPH.
FURTHER WEST...THE CONVECTION DEVELOPING ACROSS NORTHEAST COLORADO IS
EXPECTED TO SPREAD EAST EARLY TONIGHT BUT STAY NORTH OF THE
INTERSTATE 70 DURING THE OVERNIGHT HOURS. THE COLD POOL THAT IS
FORECAST TO DEVELOP WITH THESE STORMS OVERNIGHT SHOULD PUSH THE
COLD FRONT SOUTH ACROSS ALL OF SOUTHWEST KANSAS AFTER MIDNIGHT. BY
EARLY THURSDAY MORNING THIS COLD FRONT IS EXPECTED TO BE LOCATED
ACROSS CENTRAL KANSAS AND NORTHERN OKLAHOMA. BOUNDARY LAYER WINDS
BEHIND THIS FRONT ARE FORECAST TO RANGE FROM 30 TO 35 KNOTS AND
GIVEN THE TIGHT PRESSURE GRADIENT BEHIND THIS FRONT THE SURFACE WINDS
MAY APPROACH ADVISORY CRITERIA FOR A FEW HOURS FOLLOWING THE
FRONTAL PASSAGE LATE TONIGHT. AT THIS TIME HAVE DECIDED TO KEEP
SUSTAINED WINDS JUST BELOW ADVISORY CRITERIA FOR A FEW HOURS
BEHIND THIS FRONT. IN ADDITION TO THE WINDS SOME LOW LEVEL
MOISTURE WILL RETURN TO NORTH CENTRAL AND SOUTHWEST KANSAS. THE
WRF AND NMM EVEN SUGGESTS SOME LIGHT PRECIPITATION WILL BE
POSSIBLE AS THE LOWER LEVELS SATURATES. AT THIS TIME GIVEN THE ISENTROPIC
DOWNGLIDE PRESENT AND DEPTH OF THE MOIST LAYER LESS THAN 3000 FEET
AM TRENDING AWAY FROM INSERTING PRECIPITATION CHANCES AFTER
MIDNIGHT.
ON THURSDAY THE GUSTY NORTHWEST WINDS WILL GRADUALLY SUBSIDE BY
MID MORNING AS THE COLD FRONT CONTINUES TO MOVE SOUTHEAST ACROSS
EASTERN KANSAS AND OKLAHOMA. IN SOUTHEAST COLORADO THIS FRONT IS
EXPECTED TO BECOME NEARLY STATIONARY DURING THE DAY WITH SOME
ISENTROPIC LIFT/WARM AIR ADVECTION DEVELOPING NORTH OF THIS
BOUNDARY BY LATE DAY. THIS MAY BRING AN INCREASE IN MID LEVEL CLOUD
COVER LATE DAY TO PORTIONS OF SOUTHWEST KANSAS BASED ON I310 AND
I315 ISENTROPIC SURFACES AND 12Z BUFR SOUNDINGS. GIVEN SOME
INCREASING CLOUDS LATE DAY AND 850MB TEMPERATURES AT 00Z FRIDAY
WILL TREND TOWARDS THE COOLER GUIDANCE IN FAR SOUTHWEST KANSAS
NEAR THE OKLAHOMA BORDER WHILE FURTHER NORTH HAVE KEPT HIGHS
CLOSER TO THE WARMER 850MB MIX DOWN TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 234 PM CDT WED MAY 23 2012
THURSDAY NIGHT:
NOT THAT IMPRESSED FOR PROSPECTS OF CONVECTION THURSDAY EVENING. SOME
ISENTROPIC LIFT IS EXPECTED ALONG THE 700 HPA BAROCLINIC BOUNDARY ACROSS
CENTRAL KANSAS. FORECAST SOUNDINGS FROM THE ECMWF/GFS SHOW THAT THERE
MAY BE SOME MID LEVEL CLOUDS, HOWEVER, THE OVERALL PROFILE IS FAIRLY
DRY AND CAPPED. WENT AHEAD AND THREW IN SOME SILENT POPS ACROSS MY NORTHERN
COUNTIES BUT DISCOUNTED THE WETTER GFS SOLUTION WHICH CONTINUES TO SUFFER
FROM OVERALL POOR SYNOPTIC PERFORMANCE. THE 4 KM NAM & ARW/NMM CORES
AREN`T TOO CONVINCING EITHER.
FRIDAY:
THE WARM SECTOR WILL CONTINUE TO SPREAD NORTHWARD DOWNSTREAM OF A SLOWLY
PROPAGATING 500 HPA TROUGH FURTHER WEST. TEMPERATURES WARM TO 33 DEG
C @ 850 HPA AND 15 DEG C & 700 HPA WITH A WELL MIXED ATMOSPHERE. HAVE
WARMED TEMPERATURES TO THE MID TO UPPER 90S DEG F ACROSS THE CENTRAL
AND SOUTHERN ZONES AS A RESULT. THE ECMWF IS VERY WARM WITH 102 DEG
F FOR DODGE CITY FRIDAY. WILL CONTINUE TO THE TREND UPWARD BUT NOT YET
BITE ON THE EXTREME. THERE COULD BE SOME CONVECTION EAST OF THE DRYLINE
FRIDAY EVENING BUT WITH SUCH WARM TEMPERATURES AT 700 HPA, WILL NOT
GO HIGHER THAN SLIGHT GIVEN THE VERY STOUT EML. ECMWF SHOWS ABOUT 2500
J/KG OF SBCAPE AND 30 TO 40 KT OF SHEAR SO WILL HAVE TO WATCH OUT
FOR SEVERE IN LATER FORECASTS.
SATURDAY:
AMPLIFICATION OF THE WESTERN TROUGH IS EXPECTED SATURDAY. THE 12Z ECMWF
IS LESS AGGRESSIVE WITH CONVECTION FOR SATURDAY EVENING ACROSS THE WEST
THAN COMPARED TO THE 00Z RUN. THIS IS PROBABLY DUE TO THE CONTINUED
STRONG EML FORECAST BY THE MODEL. WILL NOT GO HIGHER THAN SLIGHT POPS
IN THE MEANTIME. NOT MUCH UPPER LEVEL SUPPORT AS THE MAIN 250 HPA JET
AXIS IS STILL PRETTY FAR WEST. WILL CONTINUE HOT TEMPERATURES IN THE
GRIDS WITH MID TO UPPER 90S DEG F EXPECTED ACROSS MUCH OF THE REGION.
SUNDAY AND BEYOND:
CONVECTIVE PROSPECTS ARE BETTER SUNDAY AS THE RIGHT ENTRANCE REGION
OF THE AFOREMENTIONED 250 HPA TRAVERSES ACROSS NW KANSAS. CAA ASSOCIATED
WITH THE TROUGH AND LOW TO MID LEVEL COLD POOLS WILL ALLOW FOR A WEAKENING
OF THE EML. THE BEST CHANCE FOR CONVECTION APPEARS TO BE ACROSS CENTRAL
AND SOUTH CENTRAL KANSAS ALONG AND EASTWARD MIXING DRYLINE. THE
THERMODYNAMIC AND KINEMATIC PROFILES ARE SUPPORTIVE OF SEVERE WEATHER.
UL FLOW FLATTENS MONDAY AND TUESDAY AS THE ASSOCIATED TROUGH MOVES ACROSS
THE CANADIAN PRAIRIES. THIS WILL ALLOW FOR MORE SEASONAL YET ABOVE NORMAL
TEMPERATURES ACROSS SW KANSAS. WILL HAVE TO WATCH THE MIDWEEK PERIOD
NEXT WEEK AS IT TRANSITIONS INTO MORE OF A MCS PATTERN. DEWPOINTS/MOISTURE
COULD BE AN ISSUE THOUGH. HAVE GONE WITH A CLEANED UP VERSION OF ALLBLEND
POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1233 AM CDT THU MAY 24 2012
AS A FRONT MOVES ACROSS CENTRAL KANSAS, SOUTH WINDS WILL SHIFT TO
THE NORTH OR NORTHEAST AND GUST BRIEFLY INTO THE 25 TO 30 KNOT
RANGE. AFTER 09Z, EXPECT NORTHWEST WINDS IN THE 15 TO 20 KNOT
RANGE. AS HIGH PRESSURE SETTLES SOUTH INTO THE TAF AREAS THURSDAY
MORNING, WINDS WILL NORTHWEST WINDS WILL SUBSIDE TO AROUND 12 TO 3
KNOTS. THE ONLY CLOUDS EXPECTED ARE HIGH CIRRUS CLOUDS IN THE
150-200 THOUSAND FOOT RANGE, SO VFR CONDITIONS WILL PREVAIL THROUGH
THE 24 HOUR TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 97 70 97 / 10 10 10 20
GCK 60 96 68 95 / 10 10 10 20
EHA 59 96 66 95 / 10 10 10 20
LBL 62 100 68 96 / 10 10 10 20
HYS 59 86 69 97 / 10 20 20 10
P28 67 97 72 97 / 10 20 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 AM CDT /3 AM MDT/ EARLY THIS MORNING FOR
KSZ043-044-061>063-074>077.
&&
$$
SHORT TERM...BURGERT
LONG TERM...SUGDEN
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1122 PM MDT WED MAY 23 2012
.SHORT TERM...(THIS AFTERNOON THROUGH TONIGHT)
ISSUED AT 1245 PM MDT WED MAY 23 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
ACROSS THE NORTHERN ROCKIES...WITH WEST/SOUTHWEST FLOW ACROSS THE
INTER-MOUNTAIN WEST INTO THE CENTRAL HIGH PLAINS. AT THE SURFACE A COLD
FRONT HAS STALLED OVER WESTERN KANSAS...CURRENTLY ACROSS THE EASTERN
PART OF THE CWA.
A SHORTWAVE TROUGH CURRENTLY OVER THE GREAT BASIN WILL MOVE
EAST-NORTHEAST ACROSS NORTH CENTRAL COLORADO AND SOUTHWEST NEBRASKA
TONIGHT. SHOWERS/THUNDERSTORMS HAVE ALREADY DEVELOPED AHEAD OF THIS
FEATURE ALONG THE FRONT RANGE INTO SOUTHEASTERN WYOMING. THIS
ACTIVITY WILL SPREAD SOUTH AND EAST OVER OUR CWA LATER THIS
AFTERNOON...WITH COVERAGE INCREASING ACROSS THE NORTHERN PART OF OUR
FORECAST AREA THROUGH 06Z. CONVERGENCE ZONE ALONG AND NORTH OF
STALLED FRONT COULD ACT AS A FOCUS FOR EARLIER THUNDERSTORM
INITIATION LATER THIS AFTERNOON AND EVENING...HOWEVER THIS IS
REMOVED FROM LARGE SCALE ASCENT ASSOCIATED WITH SHORTWAVE SO
COVERAGE SHOULD BE LIMITED ACROSS THE SOUTH. VERY STRONG SHEAR IS
PRESENT ACROSS THE CWA...WITH INSTABILITY DECREASING THE FURTHER
NORTH IN THE CWA WHERE TD VALUES IN THE 30-40F RANGE HAVE ADVECTED
IN BEHIND THE FRONT. SEVERE CONVECTION SHOULD BE LIMITED TO THE I-70
CORRIDOR THROUGH EARLY EVENING WHERE THE BEST OVERLAP BETWEEN
SHEAR/INSTABILITY IS EXPECTED. LATER TONIGHT ELEVATED INSTABILITY
COULD COMBINE WITH STRONG UPPER LEVEL DYNAMICS ASSOCIATED WITH THE
SHORTWAVE ACROSS SOUTHWEST NEBRASKA TO BRING ADDITIONAL SEVERE
CHANCES. SUBSIDENCE QUICKLY BUILDS IN BEHIND DEPARTING SHORTWAVE
TROUGH AFTER 06Z...WITH COVERAGE DECREASING FROM THE SOUTHWEST TO
THE NORTHEAST THROUGH SUNRISE THURSDAY.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 224 PM MDT WED MAY 23 2012
THURSDAY-THURSDAY NIGHT...PV ANOMALY WILL LIFT TO THE NORTH AND EAST
OF THE AREA FAIRLY QUICKLY DURING THE MORNING HOURS...WITH MID LEVEL
FRONTOGENESIS QUICKLY DIMINISHING AND DEEP LAYER DIV Q FIELDS
INDICATE FAIRLY STRONG LARGE SCALE FORCING FOR SUBSIDENCE OVER THE
AREA. STILL HAVE A FEW TIMING CONCERNS THOUGH...AND THINK HOLDING
ONTO SOME SMALL POPS WARRANTED FOR AT LEAST THE FIRST FEW HOURS OF
THE PERIOD. SOUNDINGS SUGGEST THAT WEAK INSTABILITY WILL LINGER
ACROSS MUCH OF THE AREA THROUGH THE DAY...AS DIFFERENTIAL TEMP
ADVECTION SHOULD LEAD TO THE DEVELOPMENT OF SHALLOW SFC BASED
INSTABILITY WITH EQUILIBRIUM LEVELS LESS THAN H5 AT MANY LOCATIONS.
ALTHOUGH SUBSIDENCE DIMINISHES IN THE AFTERNOON ACROSS SOUTHERN HALF
OF CWA...THINKING ANY AFTERNOON SHOWERS WILL BE STRONGLY DIURNALLY
DRIVEN AND THINK OVERALL COVERAGE WILL BE FAIRLY LOW THROUGH THE
EARLY EVENING. LARGE SCALE ASCENT WILL ONCE AGAIN WITH STRONG LOW
LEVEL WAA DEVELOPING IN RESPONSE TO H3 JET STREAK LIFTING NORTH INTO
SOUTHERN SOUTH DAKOTA. SEEMS LIKE RECENT SUITE OF MODELS NOT ALL
THAT OPTIMISTIC ABOUT BREAKING OUT PRECIPITATION OVERNIGHT...BUT
GIVEN STRONG AND PERSISTENT WAA/ISENTROPIC FORCING STRONG MOISTURE
TRANSPORT ABOVE THE SFC...AND SMALL CONDENSATION PRESSURE DEFICITS
IN AREA OF NEGATIVE THETA E LAPSE RATES...THINK THE THREAT FOR
SHOWERS AND STORMS WILL BE THERE DESPITE CURRENT MODEL QPF OUTPUT.
FRIDAY-SATURDAY...WARM FRONT WILL SLOWLY LIFT TO THE NORTH THROUGH
THE PERIOD AND WILL NOT ONLY PLAY A BIG ROLE ON POTENTIAL FOR
THUNDERSTORMS...IT WILL ALSO HAVE A LARGE ROLE IN TEMPERATURE
FORECAST AS POSSIBILITY EXISTS FOR A PRETTY SHARP GRADIENT WITH
TEMPS ON FRIDAY. SREF PLUME DATA INDICATING NEARLY A 20 DEGREE
SPREAD IN TEMPS FOR MOST LOCATIONS...WITH ABOUT EQUAL CLUSTERING ON
EITHER SIDE...MAINLY ON FRIDAY. PLAN ON KEEPING NEAR MEAN VALUES FOR
FRIDAY...ALTHOUGH THERE IS MUCH MORE AGREEMENT ON VERY WARM TEMPS ON
SATURDAY AND HAVE WARMED TEMPS ACCORDINGLY.
GIVEN EXPECTED PRESSURE FALL PATTERN AROUND AREA AND LARGE SCALE
FORCING FOR ASCENT BECOMING MAXIMIZED WELL TO THE WEST OF THE
AREA...DO NOT ANTICIPATE MUCH OF A NORTHERN MOVEMENT OF THE
FRONT...WITH BULK OF CWA REMAINING CLOUDY AND COOL THROUGH THE DAY.
THINK THUNDERSTORMS WILL LIKELY BE ONGOING THROUGH THE MORNING HOURS
AS PREVIOUSLY MENTIONED WAA PATTERN REMAINS IN PLACE THROUGH THE
MORNING HOURS...BEFORE LARGE SUBSIDENCE INVERSION STRENGTHENS DURING
THE AFTERNOON SHARPLY INCREASING CINH PROFILES AND ADVECTING MUCH
DRIER AIR INTO THE AREA. MODELS CONTINUE TO PRODUCE LIGHT
PRECIPITATION AFTER THIS POINT...BUT SOUNDINGS LOOK LIKE ANY
PRECIPITATION PROCESSES IN THE LATE AFTERNOON OR EVENING LOOK TO BE
VERY SHALLOW/DRIZZLE TYPE PROCESSES AND DO NOT PLAN ON GOING ALONG
WITH HIGHER GUIDANCE POPS AT THIS TIME. APPEARS TO BE LOTS OF
INSTABILITY DURING THE LATE AFTERNOON AND EVENING ALONG/NORTH OF
FRONT...BUT CINH LOOKS VERY STRONG AND GIVEN RIDGING ALOFT DO NOT
THINK THIS WILL BE OVERCOME.
ON SATURDAY...EXPECT WINDY TO VERY WINDY CONDITIONS TO DEVELOP
ACROSS MUCH OF THE AREA DURING THE AFTERNOON WITH STRONGEST WINDS
BEHIND DRYLINE IN EASTERN COLORADO...WHERE DEEP MIXED LAYER SHOULD
TAP INTO STRONG FLOW ALOFT. WITH TEMPS IN THE 90S...WIND GUSTS
APPROACHING 50 KTS AND MIXED TDS SUGGESTING A RAPID DROP OFF IN
DEWPOINTS...POTENTIAL EXISTS FOR EXTREMELY CRITICAL FIRE WX
CONDITIONS TO DEVELOP. IT IS A BIT TOO FAR IN THE FUTURE TO ISSUE
ANY HIGHLIGHTS AT THIS POINT...BUT POTENTIAL FOR FIRE WEATHER AND
SIGNIFICANT WINDS IS INCREASING. OTHERWISE...WARM FRONT WILL LIFT TO
THE NORTH OUT OF THE AREA DURING THE MORNING HOURS WITH ANY
POTENTIAL FOR AFTERNOON THUNDERSTORMS ALONG DRYLINE DURING THE LATE
AFTERNOON. WITH DEEP MIXING AND BULK OF PRESSURE FALLS TO THE NORTH
OF THE AREA...WOULD EXPECT DRYLINE TO MIX EASTWARD WITH BULK OF CWA
IN DRY SECTOR. ENOUGH SPREAD EXISTS TO WARRANT A MORE BROAD BRUSHED
APPROACH TO CHANCES ATTM THOUGH AND WITH STRONG FLOW ALOFT THERE
WILL BE POTENTIAL FOR AT LEAST A FEW STRONG/SEVERE HIGH BASED STORMS
IN THE AFTERNOON.
IN THE EXTENDED (SAT NIGHT-WEDNESDAY)...ACTIVE WEATHER PATTERN
EXPECTED THROUGH THE PERIOD AS MEDIUM RANGE MODELS SHOWING
REASONABLE AGREEMENT IN DEVELOPMENT OF STRONG TROUGH/AMPLIFIED
PATTERN ACROSS THE PLAINS THROUGH THE WEEKEND...FOLLOWED BY MORE
ZONAL FLOW ALOFT DURING THE BEGINNING OF THE WEEK. WHILE 06Z GEFS
DATA SHOWS A RELATIVELY CONSISTENT PATTERN WITH LARGE TROUGH
IMPACTING THE AREA DURING THE WEEKEND...MODEL SPREAD/UNCERTAINTY
INCREASES DURING THE LATER HALF AS THERE APPEARS TO BE A DECENT
AMOUNT OF DISCREPANCY WITH SMALL SCALE FEATURES. BEST CHANCE FOR
PRECIPITATION WILL LIKELY BE ON SUNDAY AFTERNOON AS COLD FRONT
SLOWLY MOVES ACROSS THE AREA PROVIDING AMPLE FORCING TO FOCUS
THUNDERSTORM DEVELOPMENT. WITH LIGHT EASTERLY/UPSLOPE FLOW AND
SEVERAL FAST MOVING SHORT WAVE TROUGHS MOVING THROUGH ZONAL
FLOW...PRECIP CHANCES WILL CONTINUE THROUGH THE MIDDLE OF THE WEEK.
ASIDE FROM TIMING WITH FROPA ON SUNDAY BRINGING THE POTENTIAL FOR
ONE MORE VERY WARM DAY...LOOKS LIKE COOLER CONDITIONS WILL PREVAIL
THROUGH THE START OF THE WEEK AS LIGHT EASTERLY FLOW WILL PREVAIL
BEHIND COLD FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1117 PM MDT WED MAY 23 2012
SHOWERS AND THUNDERSTORMS WILL CONTINUE OVERNIGHT AT BOTH KGLD AND
KMCK. DO NOT EXPECT CONDITIONS TO DETERIORATE BELOW VFR BUT CANNOT
RULE OUT A BRIEF PERIOD OF MVFR NEAR A STRONG THUNDERSTORM. THE
SHORTWAVE SHOULD EXIT BY SUNRISE. BROKEN TO SCATTERED MID LEVEL
CLOUDS WILL PASS OVER THE REGION THURSDAY. CLOUDS WILL INCREASE
AGAIN FRIDAY EVENING WITH A SLIGHT CHANCE OF SOME SHOWERS.
&&
.FIRE WEATHER...
ISSUED AT 224 PM MDT WED MAY 23 2012
VERY WINDY CONDITIONS...WITH GUSTS IN EXCESS OF 50 MPH
POSSIBLE...ARE EXPECTED ACROSS A LARGE PORTION OF THE AREA ON
SATURDAY. AFTERNOON HUMIDITIES WILL FALL TO AROUND 10 PERCENT
ACROSS PORTIONS OF EASTERN COLORADO AND ADJACENT AREAS DURING THE
AFTERNOON AS THE WINDS INCREASE. THE COMBINATION OF VERY DRY AND
VERY WINDY CONDITIONS WILL BRING THE POTENTIAL FOR EXTREMELY
CRITICAL CONDITIONS ON SATURDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JRM
AVIATION...FS
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
602 AM EDT THU MAY 24 2012
.SYNOPSIS...
ISSUED AT 504 AM EDT THU MAY 24 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE UPR
RDG OVER THE NE CONUS/SE CANADA DOWNSTREAM OF DEEP UPR TROF IN THE
ROCKIES. UNDER THE SW FLOW ALF BTWN THESE LARGER SCALE FEATURES...A
SHRTWV/SFC LO LIFTING NEWD NEAR LK WINNIPEG WITH UPR DVGC IN RRQ OF
SUPPORTING 100KT H3 JET MAX HAS CAUSED QUITE A BIT OF SHRA/TS IN MN
MAINLY WITHIN AXIS OF DEEPER MSTR ON THE COLD SIDE OF SFC FNT OVER
WRN LK SUP THAT IS ATTENDANT TO LK WINNIPEG LO. A FEW -SHRA/A LTG
STRIKE OF TWO ARE JUST W OF IWD NEAR THE SFC COLD FNT LOCATION NOT
FAR FM ASHLAND IN NW WI. TO THE E OVER MOST OF THE CWA...BONE DRY
AIRMASS SHOWN ON THE 00Z GRB RAOB /PWAT 0.25 INCH WITH KINX -53/ IS
BRINGING A TRANQUIL OVERNGT WITH JUST SOME SCT HI CLDS. THE APRCH OF
ANOTHER STRONG SHRTWV ROTATING THRU THE WRN TROF IS CAUSING MORE
SHRA/TS TO BREAK OUT IN NEBRASKA UNDER EXPANDING AREA OF COOLING CLD
TOPS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 504 AM EDT THU MAY 24 2012
MAIN FCST CONCERN DURING THIS TIME IS POTENTIAL FOR SVR WX LATE THIS
EVNG ASSOCIATED WITH SHRTWV NOW ROUNDING THE BASE OF THE WRN TROF
AND CAUSING EXPANDING AREA OF SHRA/TS AROUND NEBRASKA.
TDAY...ALTHOUGH SOME OF THE SCT -SHRA NOW ALONG THE COLD FNT WL
DRIFT INTO THE WRN ZNS EARLY THIS MRNG PER SLOWLY VEERING H85 FLOW
TO SW AS SHOWN BY THE 00Z NAM...THE BULK OF THE RA NOW IN MN WL STAY
W AND DIMINISH AS POCKET OF UPR DVGC IN RRQ OF JET MAX IN NW ONTARIO
LIFTS TO THE NE. BUT WITH DRYNESS OF AIRMASS IN PLACE PER THE 00Z
GRB RAOB AND HI AMPLITUDE RDG JUST TO THE E...THESE -SHRA SHOULD
REMAIN OVER THE W AS THE SLOW MOVING COLD FNT STALLS WITH BACKING OF
THE UPR FLOW ASSOCIATED WITH MOTION OF ROCKIES SHRTWV INTO THE
PLAINS. THEN MOST OF THE DAY WILL FEATURE A GUSTY S WIND AS H85 WINDS
INCRS TO 40-45KTS IN ADVANCE OF THE SHRTWV/DVLPG SFC LO IN THE
PLAINS THAT IS FCST TO LIFT NEWD TO NOT FAR FM DLH BY 00Z. CONFINED
CHC POPS TO THE W. DAYTIME HEATING/MIXING WL CAUSE WIND GUSTS TO AT
LEAST APRCH ADVY CRITERIA WITH STEEP LLVL LAPSE RATES AS HI TEMPS
SURGE INTO THE 80S AT SOME PLACES AWAY FM THE MODERATING INFLUENCE
OF MAINLY LK MI. AFT COORDINATION WITH GRB...OPTED TO ISSUE WIND
ADVY FOR MAINLY THE W HALF OF THE CWA AWAY FM THE MORE STABILIZED
KEWEENAW PENINSULA TO ACCOUNT FOR DEEP MIXING...EXCEPTIONAL
INTENSITY OF THE APRCHG DISTURBANCE/SFC LO PRES...AND GFS FCST
H85/H925 S WINDS UP TO 60KTS/50KTS. GFS BUFKIT PROFILES INDICATE
WINDS OF 35-40 KTS WL BE PRESENT IN MIXED LYR AT IWD. ALTHOUGH THE
ARRIVAL OF HIER H95-9 SPECIFIC HUMIDITY IN THIS STRENGTHENING SLY
FLOW WL KEEP MIN RH FM FALLING TO CRITICAL LVLS...THE GUSTY S WINDS
WL STILL BE A CHALLENGE FOR THE PERSONNEL FIGHTING THE SENEY
FIRE/OTHER WILDFIRES. MORE NMRS SHRA/TS ASSOCIATED WITH THE LO
MOVING NEAR DLH MAY ARRIVE OVER THE FAR W IN THE 21Z-24Z TIME.
TNGT...AS THE NEGATIVELY TILTED SHRTWV/SFC LO MOVE QUICKLY NE INTO
ONTARIO...EXPECT A STRONG COLD FROPA ACRS THE CWA. VERY STRONG
DYNAMICS THAT IMPACT MAINLY THE W HALF INCLUDE VIGOROUS DPVA/UPR
DVGC IN THE LEFT EXIT OF SUPPORTING 130KT H3 JET MAX. ALTHOUGH FCST
SDNGS DO NOT SHOW PARTICULARLY STEEP MID LVL LAPSE RATES...INVERTED
V LOOK TO THE T/TD PROFILE IN THE SUB H8-85 LYR FOR IWD AT 00Z WITH
EARLY EVNG FROPA THERE MAXIMIZING LLVL DESTABLIZATION AT PEAK
HEATING TIME SUG THE POTENTIAL FOR DAMAGING WINDS WITH
UNIDIRECTIONAL/SLOWLY VEERING POWERFUL FLOW THAT INCLUDES H7/H85
WINDS AS HI AS 60-70KTS/50-60KTS EVEN THOUGH THERE IS NOT A LOT OF
MID LVL DRY AIR TO MAXIMIZE DCAPE. DESPITE THE STRONG WIND
FIELDS...INVERTED V LLVL T/TD PROFILE AND LACK OF DIRECTIONAL SHEAR
WOULD TEND TO MINIMIZE TORNADO THREAT. SINCE THE MID LVL LAPSE RATES
ARE RELATIVELY WEAK AND LACK OF DRY MID LVL AIR RESULTS IN WBZ HGT
IN THE 12.5-13.0K RANGE...THE LARGE HAIL THREAT DOES NOT APPEAR TOO
HI. SINCE THE SHARPER DYNAMICS WL EXIT TO THE NE AND NOCTURNAL
COOLING WL BEGIN TO HAVE AN IMPACT...EXPECT THE SHRA/TS CHCS AND
SEVERE WX THREAT TO WANE AS THE FRONT MARCHES FARTHER E. VIGOROUS
DRY SLOTTING/ARRIVAL OF LARGER SCALE QVECTOR DVGC IN THE WAKE OF THE
FROPA WL CAUSE DIMINISHING POPS...BUT LINGERING LLVL MSTR MAY STILL
CAUSE A FEW -SHRA IN THE UPSLOPE AREAS OF THE W THRU THE NGT.
GIVEN STRENGTH OF THIS DISTURBANCE...CONCERNED W WINDS IN THE WAKE
OF THE COLD FROPA WL REACH ADVY CRITERIA OVER MAINLY THE EXPOSED
KEWEENAW PENINSULA AFT 06Z WITH W H925 WINDS INCRSG TO 40-50
KTS/VIGOROUS CAD THAT WL MAINTAIN STEEPER LLVL LAPSE RATES DESPITE
SOME STABILIZATION OVER THE RELATIVELY COOL WATERS OF LK SUP/AND
APRCH OF PRES RISE MAX OF 10-15MB/6HRS THAT WL ACCENTUATE
ISALLOBARIC WIND COMPONENT NEARLY IN LINE WITH GRADIENT FLOW.
FRI...WITH THE ARRIVAL OF DRIER AIR AND APRCH OF UPR RDG...EXPECT A
DRY DAY. GUSTY WINDS WL PERSIST WITH DAYTIME HEATING/MIXING EVEN
THOUGH THE PRES GRADIENT IS FCST TO SLOWLY SLACKEN. WITH H85 TEMPS
TOPPING OUT IN THE 8-10C RANGE...MIXING TO H75 ON GFS/NAM FCST SDNGS
YIELD HI TEMPS IN THE 75-80 RANGE WITH DOWNSLOPING FLOW AWAY FM LK
MODERATION IN LLVL WNW FLOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
MAIN CONCERN FOR THE LONG TERM PERIOD IS THE SEVERE WEATHER
POTENTIAL AT THE BEGINNING OF THE PERIOD.
STATIONARY FRONT WILL BE SETUP OVER WRN LK SUPERIOR...WHILE A FAIRLY
POTENT SHORTWAVE PUSHING NE ACROSS AT LEAST THE WRN HALF OF THE CWA
THURS NIGHT. THIS WILL LEAD TO ONGOING CYCLOGENESIS OVER NW WI
DURING THE LATE AFTERNOON AND THE LOW MOVING NNE ACROSS WRN LK
SUPERIOR DURING THE EVENING. EXPECT THUNDERSTORMS TO BE ONGOING
OVER NW WI AND FAR WRN LK SUPERIOR AT THE START OF THE PERIOD AND
THEN MOVE E AND NE AS THE COLD FRONT PUSHES THROUGH THE CWA DURING
THE NIGHT.
WITH THE STRONG WINDS ALOFT AND THE CYCLOGENESIS...FEEL THAT THERE
IS A DECENT CHANCE OF SEVERE WEATHER OVER THE WRN HALF OF THE CWA
TOMORROW EVENING. THERE IS A VERY THIN CORRIDOR OF MLCAPE VALUES
APPROACHING 500-1000 J/KG OVER THE WRN THIRD OF THE CWA AND
INSTABILITY MAY BE THE MAIN LIMITING FACTOR AS STORMS MOVE INTO THE
CWA. CAPE FAIRLY SKINNY...NCAPE VALUES AROUND 0.1...SO DON/T EXPECT
MUCH MORE THAN MARGINALLY SEVERE HAIL.
WIND APPEARS TO BE BIGGEST THREAT WITH THE STORMS. INVERTED V LOOK
TO THE SOUNDINGS OVER THE WEST AND DCAPE VALUES OF 600-800 J/KG.
STRONG WINDS ALOFT...APPROACHING 70-80KTS AT H700 AND
40-50KTS JUST A COUPLE HUNDRED FEET ABOVE THE SFC...WILL BE
AIDED BY A POCKET OF DRY H700-500 AIR AND STEEPER LAPSE RATES.
THIS...COMBINED WITH STORM MOTION TO THE NNE AT 65-70KTS ALL POINT
TO THE POTENTIAL FOR DAMAGING WINDS WHERE THUNDERSTORMS...AND
POTENTIALLY EVEN SHOWERS OCCUR. WITH THE LOW DEVELOPING ALONG THE
FRONT POTENTIALLY AFFECTING THE LLVL WIND FIELD...COULD SEE SOME
LLVL BACKING OF THE WINDS AND PRODUCE SOME ROTATING UPDRAFTS AND
SUPERCELLS...ESPECIALLY OVER NW WI. BUT THE EXPECTED DRY LLVL AIR
HELPING PRODUCE AN INVERTED V AND LCL HEIGHTS TOWARDS 3-3.5KFT
SHOULD LIMIT TORNADO POTENTIAL THIS FAR N.
CURRENT THOUGHT IS BEST CHANCES FOR SEVERE SHOULD BE FROM
BARAGA/IRON COUNTIES AND WEST...BUT WITH THE STORM MOTIONS...COULD
POTENTIALLY AFFECT MARQUETTE/DICKINSON/MENOMINEE COUNTIES BEFORE
HEADING OVER LK SUPERIOR. ADDED DAMAGING WIND THREAT TO THE GRIDS
AND MENTIONED IN THE HWO. THIS MATCHES UP WELL WHERE SPC HAS A
SLIGHT RISK...WITH HATCHED AREA JUST TO THE SW OF THE CWA.
AS THE LOW QUICKLY LIFTS NE...EXPECT BEST FORCING TO QUICKLY
DEPART OVERNIGHT AND PULL FORCING WITH IT. IN ADDITION...AS THE COLD
FRONT PUSHES EAST INTO THE CNTRL/ERN CWA...THE CAPPING BECOMES
STRONGER. WITH THE COMBINATION OF LOOSING FORCING AND MORE
UNFAVORABLE ENVIRONMENT...EXPECT THE SHOWERS/THUNDERSTORMS TO
DIMINISH AS THEY MOVE INTO THE CNTRL/ERN CWA. 09Z SREF ALSO SHOWING
THIS DIMINISHING TREND IN THE 3HR CALIBRATED THUNDERSTORM PROBS...AS
THE SHOWERS/THUNDERSTORMS PUSH TO THE NE OVER LK SUPERIOR DURING THE
OVERNIGHT HOURS.
EXPECT GUSTY SE WINDS IN THE EVENING AHEAD OF THE LOW AND OVER THE
KEWEENAW OVERNIGHT BEHIND THE LOW/FRONT. BUMPED UP WINDS
SIGNIFICANTLY OVER THE KEWEENAW BEHIND THE LOW AND FRONT...WITH THE
STRONG WINDS JUST ABOVE THE SFC /NAM SHOWING 60KTS AT 1.5KFT/. IN
ADDITION...GOOD ISALLOBARIC COMPONENT TO THE WINDS OVER THE WEST
OVERNIGHT WITH THE INTENSIFYING LOW PUSHING NE. ONLY CONCERN FOR
GOING MORE THAN 30-35KTS AT THIS POINT IS AFFECT OF COOLER WATER
TEMPS...BUT THAT MAY NOT HAVE MUCH EFFECT OVER THE HIGHER TERRAIN.
FRI...GUSTY WRLY WINDS...30-35KTS...IN THE MORNING BEHIND THE LOW.
DRIER AIR MOVING IN AND H700 CAP SHOULD LIMIT DEVELOPMENT EVEN WITH
WEAK MID-LVL WAVE MOVING THROUGH. DEEP MOISTURE IS LIMITED AND ML/MU
CAPE VALUES ARE BELOW 100 JKG WOULD LEAD TO LITTLE/NO PCPN CHANCES.
LATEST NAM RUN HAS BACKED OFF ON PCPN AND WILL FOLLOW SUIT WITH
REMOVING SLIGHT CHANCES. WILL KEEP SKIES PARTLY/MOSTLY CLOUDY DURING
THE AFTN WITH EXPECTED DIURNAL CU DEVELOPMENT.
MIXING TO H750 WOULD YIELD HIGHS IN THE 70S...WITH THE HIGHEST
VALUES IN THE FAVORED DOWNSLOPE AREAS OF THE CNTRL. WITH THE GUSTY
WINDS AND DEEPER MIXING INTO THE LIMITED MOISTURE ALOFT...EXPECT RH
VALUES TO FALL TO 30 PERCENT. FIRE WX CONCERNS MAINLY OVER THE
CNTRL...WHERE LESS RAIN IS EXPECTED ON THURS NIGHT.
FRI NIGHT...WEAK HIGH PRESSURE RIDGE FROM HIGH JUST N OF MN. SFC LOW
DEVELOPING IN THE CNTRL PLAINS IN RESPONSE TO DEEP UPPER TROUGH
OVER THE WRN CONUS WILL BEGIN TO PUSH A WARM FRONT N TOWARDS THE
UPPER GREAT LAKES LATE FRI NIGHT. COULD PRODUCE A FEW SHOWERS
TOWARDS THE WI BORDER LATE.
CWA WILL BE ON THE E SIDE OF THE UPPER RIDGE AXIS STRETCHING FROM
THE OHIO VALLEY TO LK WINNIPEG UNTIL SUN NIGHT. STILL SEVERAL WEAK
DISTURBANCES PUSHING THROUGH THE FLOW SAT AFTN THROUGH SUN NIGHT.
THE WARM FRONT WILL CONTINUE TO SLOWLY PUSH NE ON SAT...AS IT
BATTLES THE HIGH THAT WILL HAVE MOVED EAST OVER ONTARIO. PCPN
CHANCES ON SAT WILL LARGELY DEPEND ON HOW FAR N THE FRONT WILL PUSH.
BEST CHANCES LOOK TO BE ON SAT NIGHT INTO SUN...AS THE FRONT MOVES
INTO NRN WI AND FINALLY INTO UPPER MI BY SUN AFTN. THIS WILL PUT THE
BEST WAA FOCUS OVER THE CWA. THERE ARE DECENT MID LEVEL LAPSE
RATES...BUT ELEVATED CAPES ARE NOT TOO IMPRESSIVE...SO HAVE CAPPED
THUNDER TO CHANCES FOR SAT NIGHT INTO SUN. WITH THE CONVECTION
LIKELY TO BE ELEVATED...THE MAIN THREAT WOULD BE SMALL HAIL AND
HEAVY RAIN.
CWA WILL BE UNDER THE WARM SECTOR LATE SUN AFTN AND INTO SUN
NIGHT...WITH MODELS DIVERGING WITH THE HANDLING OF THE LOW HEADING
INTO THE FIRST PART OF NEXT WEEK. 12Z GFS SHOWS THE LOW CONTINUING
NNE INTO SRN CANADA ON SUN NIGHT AND MONDAY WHILE PUSHING COLD FRONT
ACROSS UPPER MI ON MON. 00Z ECMWF ON THE OTHERHAND DISSIPATES THE
LOW OVER THE CWA AND THEN SLOWLY SLIDES IT EAST THROUGH TUES. AFTER
A MORE ACTIVE PERIOD...OVERALL TREND LOOKS TO BE TOWARDS A SLIGHTLY
DRIER/QUIET WEATHER TOWARDS THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 557 AM EDT THU MAY 24 2012
STRONG WINDS AND LLWS REMAIN A CONCERN THROUGH 12Z FRIDAY. SSW WINDS
OF 50-55KTS CONTINUE TO SHOW UP ON THE MARQUETTE 88D RADAR...WHICH
SHOULD ONLY TEMPORARILY DIMINISH ABOUT 5KTS OR SO BEFORE PICKING UP
AGAIN THIS AFTERNOON...WITH 60KTS JUST AHEAD OF THE NEARING COLD
FRONT TO OUR WEST. SHOWERS AND THUNDERSTORMS NEAR IWD AND CMX EARLY
THIS MORNING WILL SLOWLY TRACK TO SAW AROUND OR SHORTLY AFTER 00Z
FRIDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ALONG THE COLD
FRONT DURING THE AFTERNOON AND EVENING WITH CONVECTION...BEFORE
DIMINISHING LATE TONIGHT. STRONG WINDS WILL REMAIN ALOFT...IF NOT AT
THE SURFACE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT WED MAY 23 2012
LOW PRESSURE OVER S MANITOBA WILL PUSH INTO ONTARIO TONIGHT AND
THURSDAY...AS AN ADDITIONAL LOW MOVES FROM THE CENTRAL PLAINS TO W
LS FRIDAY AFTERNOON. EXPECT THE LOW TO CONTINUE A NE TRACK ACROSS
ONTARIO THROUGH FRIDAY...WITH A TROUGH LINGERING ACROSS LAKE
SUPERIOR. STRENGTHENING S WINDS WILL PREVAIL AHEAD OF THIS SYSTEM
TONIGHT THROUGH THURSDAY. WITH A STABLE TEMPERATURE PROFILE THE
STRONGEST WINDS...EXPECT THE STRONGEST ACROSS THE TALLER OBSERVING
PLATFORMS ACROSS CENTRAL LAKE SUPERIOR.
HIGH PRESSURE OVER CENTRAL CANADA FRIDAY NIGHT WILL SLIDE ACROSS
ONTARIO SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON SUNDAY. AS A
RESULT...A RIDGE WILL SLIDE ACROSS LS SATURDAY...WITH LIGHTER WINDS
TAKING HOLD. A LOW ACROSS THE CENTRAL PLAINS WILL FILL ACROSS MN
SUNDAY INTO SUNDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY FROM 1 PM EDT /NOON CDT/ THIS AFTERNOON TO 8 PM
EDT /7 PM CDT/ THIS EVENING FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR LSZ263-
264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
505 AM EDT THU MAY 24 2012
.SYNOPSIS...
ISSUED AT 504 AM EDT THU MAY 24 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE UPR
RDG OVER THE NE CONUS/SE CANADA DOWNSTREAM OF DEEP UPR TROF IN THE
ROCKIES. UNDER THE SW FLOW ALF BTWN THESE LARGER SCALE FEATURES...A
SHRTWV/SFC LO LIFTING NEWD NEAR LK WINNIPEG WITH UPR DVGC IN RRQ OF
SUPPORTING 100KT H3 JET MAX HAS CAUSED QUITE A BIT OF SHRA/TS IN MN
MAINLY WITHIN AXIS OF DEEPER MSTR ON THE COLD SIDE OF SFC FNT OVER
WRN LK SUP THAT IS ATTENDANT TO LK WINNIPEG LO. A FEW -SHRA/A LTG
STRIKE OF TWO ARE JUST W OF IWD NEAR THE SFC COLD FNT LOCATION NOT
FAR FM ASHLAND IN NW WI. TO THE E OVER MOST OF THE CWA...BONE DRY
AIRMASS SHOWN ON THE 00Z GRB RAOB /PWAT 0.25 INCH WITH KINX -53/ IS
BRINGING A TRANQUIL OVERNGT WITH JUST SOME SCT HI CLDS. THE APRCH OF
ANOTHER STRONG SHRTWV ROTATING THRU THE WRN TROF IS CAUSING MORE
SHRA/TS TO BREAK OUT IN NEBRASKA UNDER EXPANDING AREA OF COOLING CLD
TOPS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 504 AM EDT THU MAY 24 2012
MAIN FCST CONCERN DURING THIS TIME IS POTENTIAL FOR SVR WX LATE THIS
EVNG ASSOCIATED WITH SHRTWV NOW ROUNDING THE BASE OF THE WRN TROF
AND CAUSING EXPANDING AREA OF SHRA/TS AROUND NEBRASKA.
TDAY...ALTHOUGH SOME OF THE SCT -SHRA NOW ALONG THE COLD FNT WL
DRIFT INTO THE WRN ZNS EARLY THIS MRNG PER SLOWLY VEERING H85 FLOW
TO SW AS SHOWN BY THE 00Z NAM...THE BULK OF THE RA NOW IN MN WL STAY
W AND DIMINISH AS POCKET OF UPR DVGC IN RRQ OF JET MAX IN NW ONTARIO
LIFTS TO THE NE. BUT WITH DRYNESS OF AIRMASS IN PLACE PER THE 00Z
GRB RAOB AND HI AMPLITUDE RDG JUST TO THE E...THESE -SHRA SHOULD
REMAIN OVER THE W AS THE SLOW MOVING COLD FNT STALLS WITH BACKING OF
THE UPR FLOW ASSOCIATED WITH MOTION OF ROCKIES SHRTWV INTO THE
PLAINS. THEN MOST OF THE DAY WILL FEATURE A GUSTY S WIND AS H85 WINDS
INCRS TO 40-45KTS IN ADVANCE OF THE SHRTWV/DVLPG SFC LO IN THE
PLAINS THAT IS FCST TO LIFT NEWD TO NOT FAR FM DLH BY 00Z. CONFINED
CHC POPS TO THE W. DAYTIME HEATING/MIXING WL CAUSE WIND GUSTS TO AT
LEAST APRCH ADVY CRITERIA WITH STEEP LLVL LAPSE RATES AS HI TEMPS
SURGE INTO THE 80S AT SOME PLACES AWAY FM THE MODERATING INFLUENCE
OF MAINLY LK MI. AFT COORDINATION WITH GRB...OPTED TO ISSUE WIND
ADVY FOR MAINLY THE W HALF OF THE CWA AWAY FM THE MORE STABILIZED
KEWEENAW PENINSULA TO ACCOUNT FOR DEEP MIXING...EXCEPTIONAL
INTENSITY OF THE APRCHG DISTURBANCE/SFC LO PRES...AND GFS FCST
H85/H925 S WINDS UP TO 60KTS/50KTS. GFS BUFKIT PROFILES INDICATE
WINDS OF 35-40 KTS WL BE PRESENT IN MIXED LYR AT IWD. ALTHOUGH THE
ARRIVAL OF HIER H95-9 SPECIFIC HUMIDITY IN THIS STRENGTHENING SLY
FLOW WL KEEP MIN RH FM FALLING TO CRITICAL LVLS...THE GUSTY S WINDS
WL STILL BE A CHALLENGE FOR THE PERSONNEL FIGHTING THE SENEY
FIRE/OTHER WILDFIRES. MORE NMRS SHRA/TS ASSOCIATED WITH THE LO
MOVING NEAR DLH MAY ARRIVE OVER THE FAR W IN THE 21Z-24Z TIME.
TNGT...AS THE NEGATIVELY TILTED SHRTWV/SFC LO MOVE QUICKLY NE INTO
ONTARIO...EXPECT A STRONG COLD FROPA ACRS THE CWA. VERY STRONG
DYNAMICS THAT IMPACT MAINLY THE W HALF INCLUDE VIGOROUS DPVA/UPR
DVGC IN THE LEFT EXIT OF SUPPORTING 130KT H3 JET MAX. ALTHOUGH FCST
SDNGS DO NOT SHOW PARTICULARLY STEEP MID LVL LAPSE RATES...INVERTED
V LOOK TO THE T/TD PROFILE IN THE SUB H8-85 LYR FOR IWD AT 00Z WITH
EARLY EVNG FROPA THERE MAXIMIZING LLVL DESTABLIZATION AT PEAK
HEATING TIME SUG THE POTENTIAL FOR DAMAGING WINDS WITH
UNIDIRECTIONAL/SLOWLY VEERING POWERFUL FLOW THAT INCLUDES H7/H85
WINDS AS HI AS 60-70KTS/50-60KTS EVEN THOUGH THERE IS NOT A LOT OF
MID LVL DRY AIR TO MAXIMIZE DCAPE. DESPITE THE STRONG WIND
FIELDS...INVERTED V LLVL T/TD PROFILE AND LACK OF DIRECTIONAL SHEAR
WOULD TEND TO MINIMIZE TORNADO THREAT. SINCE THE MID LVL LAPSE RATES
ARE RELATIVELY WEAK AND LACK OF DRY MID LVL AIR RESULTS IN WBZ HGT
IN THE 12.5-13.0K RANGE...THE LARGE HAIL THREAT DOES NOT APPEAR TOO
HI. SINCE THE SHARPER DYNAMICS WL EXIT TO THE NE AND NOCTURNAL
COOLING WL BEGIN TO HAVE AN IMPACT...EXPECT THE SHRA/TS CHCS AND
SEVERE WX THREAT TO WANE AS THE FRONT MARCHES FARTHER E. VIGOROUS
DRY SLOTTING/ARRIVAL OF LARGER SCALE QVECTOR DVGC IN THE WAKE OF THE
FROPA WL CAUSE DIMINISHING POPS...BUT LINGERING LLVL MSTR MAY STILL
CAUSE A FEW -SHRA IN THE UPSLOPE AREAS OF THE W THRU THE NGT.
GIVEN STRENGTH OF THIS DISTURBANCE...CONCERNED W WINDS IN THE WAKE
OF THE COLD FROPA WL REACH ADVY CRITERIA OVER MAINLY THE EXPOSED
KEWEENAW PENINSULA AFT 06Z WITH W H925 WINDS INCRSG TO 40-50
KTS/VIGOROUS CAD THAT WL MAINTAIN STEEPER LLVL LAPSE RATES DESPITE
SOME STABILIZATION OVER THE RELATIVELY COOL WATERS OF LK SUP/AND
APRCH OF PRES RISE MAX OF 10-15MB/6HRS THAT WL ACCENTUATE
ISALLOBARIC WIND COMPONENT NEARLY IN LINE WITH GRADIENT FLOW.
FRI...WITH THE ARRIVAL OF DRIER AIR AND APRCH OF UPR RDG...EXPECT A
DRY DAY. GUSTY WINDS WL PERSIST WITH DAYTIME HEATING/MIXING EVEN
THOUGH THE PRES GRADIENT IS FCST TO SLOWLY SLACKEN. WITH H85 TEMPS
TOPPING OUT IN THE 8-10C RANGE...MIXING TO H75 ON GFS/NAM FCST SDNGS
YIELD HI TEMPS IN THE 75-80 RANGE WITH DOWNSLOPING FLOW AWAY FM LK
MODERATION IN LLVL WNW FLOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
MAIN CONCERN FOR THE LONG TERM PERIOD IS THE SEVERE WEATHER
POTENTIAL AT THE BEGINNING OF THE PERIOD.
STATIONARY FRONT WILL BE SETUP OVER WRN LK SUPERIOR...WHILE A FAIRLY
POTENT SHORTWAVE PUSHING NE ACROSS AT LEAST THE WRN HALF OF THE CWA
THURS NIGHT. THIS WILL LEAD TO ONGOING CYCLOGENESIS OVER NW WI
DURING THE LATE AFTERNOON AND THE LOW MOVING NNE ACROSS WRN LK
SUPERIOR DURING THE EVENING. EXPECT THUNDERSTORMS TO BE ONGOING
OVER NW WI AND FAR WRN LK SUPERIOR AT THE START OF THE PERIOD AND
THEN MOVE E AND NE AS THE COLD FRONT PUSHES THROUGH THE CWA DURING
THE NIGHT.
WITH THE STRONG WINDS ALOFT AND THE CYCLOGENESIS...FEEL THAT THERE
IS A DECENT CHANCE OF SEVERE WEATHER OVER THE WRN HALF OF THE CWA
TOMORROW EVENING. THERE IS A VERY THIN CORRIDOR OF MLCAPE VALUES
APPROACHING 500-1000 J/KG OVER THE WRN THIRD OF THE CWA AND
INSTABILITY MAY BE THE MAIN LIMITING FACTOR AS STORMS MOVE INTO THE
CWA. CAPE FAIRLY SKINNY...NCAPE VALUES AROUND 0.1...SO DON/T EXPECT
MUCH MORE THAN MARGINALLY SEVERE HAIL.
WIND APPEARS TO BE BIGGEST THREAT WITH THE STORMS. INVERTED V LOOK
TO THE SOUNDINGS OVER THE WEST AND DCAPE VALUES OF 600-800 J/KG.
STRONG WINDS ALOFT...APPROACHING 70-80KTS AT H700 AND
40-50KTS JUST A COUPLE HUNDRED FEET ABOVE THE SFC...WILL BE
AIDED BY A POCKET OF DRY H700-500 AIR AND STEEPER LAPSE RATES.
THIS...COMBINED WITH STORM MOTION TO THE NNE AT 65-70KTS ALL POINT
TO THE POTENTIAL FOR DAMAGING WINDS WHERE THUNDERSTORMS...AND
POTENTIALLY EVEN SHOWERS OCCUR. WITH THE LOW DEVELOPING ALONG THE
FRONT POTENTIALLY AFFECTING THE LLVL WIND FIELD...COULD SEE SOME
LLVL BACKING OF THE WINDS AND PRODUCE SOME ROTATING UPDRAFTS AND
SUPERCELLS...ESPECIALLY OVER NW WI. BUT THE EXPECTED DRY LLVL AIR
HELPING PRODUCE AN INVERTED V AND LCL HEIGHTS TOWARDS 3-3.5KFT
SHOULD LIMIT TORNADO POTENTIAL THIS FAR N.
CURRENT THOUGHT IS BEST CHANCES FOR SEVERE SHOULD BE FROM
BARAGA/IRON COUNTIES AND WEST...BUT WITH THE STORM MOTIONS...COULD
POTENTIALLY AFFECT MARQUETTE/DICKINSON/MENOMINEE COUNTIES BEFORE
HEADING OVER LK SUPERIOR. ADDED DAMAGING WIND THREAT TO THE GRIDS
AND MENTIONED IN THE HWO. THIS MATCHES UP WELL WHERE SPC HAS A
SLIGHT RISK...WITH HATCHED AREA JUST TO THE SW OF THE CWA.
AS THE LOW QUICKLY LIFTS NE...EXPECT BEST FORCING TO QUICKLY
DEPART OVERNIGHT AND PULL FORCING WITH IT. IN ADDITION...AS THE COLD
FRONT PUSHES EAST INTO THE CNTRL/ERN CWA...THE CAPPING BECOMES
STRONGER. WITH THE COMBINATION OF LOOSING FORCING AND MORE
UNFAVORABLE ENVIRONMENT...EXPECT THE SHOWERS/THUNDERSTORMS TO
DIMINISH AS THEY MOVE INTO THE CNTRL/ERN CWA. 09Z SREF ALSO SHOWING
THIS DIMINISHING TREND IN THE 3HR CALIBRATED THUNDERSTORM PROBS...AS
THE SHOWERS/THUNDERSTORMS PUSH TO THE NE OVER LK SUPERIOR DURING THE
OVERNIGHT HOURS.
EXPECT GUSTY SE WINDS IN THE EVENING AHEAD OF THE LOW AND OVER THE
KEWEENAW OVERNIGHT BEHIND THE LOW/FRONT. BUMPED UP WINDS
SIGNIFICANTLY OVER THE KEWEENAW BEHIND THE LOW AND FRONT...WITH THE
STRONG WINDS JUST ABOVE THE SFC /NAM SHOWING 60KTS AT 1.5KFT/. IN
ADDITION...GOOD ISALLOBARIC COMPONENT TO THE WINDS OVER THE WEST
OVERNIGHT WITH THE INTENSIFYING LOW PUSHING NE. ONLY CONCERN FOR
GOING MORE THAN 30-35KTS AT THIS POINT IS AFFECT OF COOLER WATER
TEMPS...BUT THAT MAY NOT HAVE MUCH EFFECT OVER THE HIGHER TERRAIN.
FRI...GUSTY WRLY WINDS...30-35KTS...IN THE MORNING BEHIND THE LOW.
DRIER AIR MOVING IN AND H700 CAP SHOULD LIMIT DEVELOPMENT EVEN WITH
WEAK MID-LVL WAVE MOVING THROUGH. DEEP MOISTURE IS LIMITED AND ML/MU
CAPE VALUES ARE BELOW 100 JKG WOULD LEAD TO LITTLE/NO PCPN CHANCES.
LATEST NAM RUN HAS BACKED OFF ON PCPN AND WILL FOLLOW SUIT WITH
REMOVING SLIGHT CHANCES. WILL KEEP SKIES PARTLY/MOSTLY CLOUDY DURING
THE AFTN WITH EXPECTED DIURNAL CU DEVELOPMENT.
MIXING TO H750 WOULD YIELD HIGHS IN THE 70S...WITH THE HIGHEST
VALUES IN THE FAVORED DOWNSLOPE AREAS OF THE CNTRL. WITH THE GUSTY
WINDS AND DEEPER MIXING INTO THE LIMITED MOISTURE ALOFT...EXPECT RH
VALUES TO FALL TO 30 PERCENT. FIRE WX CONCERNS MAINLY OVER THE
CNTRL...WHERE LESS RAIN IS EXPECTED ON THURS NIGHT.
FRI NIGHT...WEAK HIGH PRESSURE RIDGE FROM HIGH JUST N OF MN. SFC LOW
DEVELOPING IN THE CNTRL PLAINS IN RESPONSE TO DEEP UPPER TROUGH
OVER THE WRN CONUS WILL BEGIN TO PUSH A WARM FRONT N TOWARDS THE
UPPER GREAT LAKES LATE FRI NIGHT. COULD PRODUCE A FEW SHOWERS
TOWARDS THE WI BORDER LATE.
CWA WILL BE ON THE E SIDE OF THE UPPER RIDGE AXIS STRETCHING FROM
THE OHIO VALLEY TO LK WINNIPEG UNTIL SUN NIGHT. STILL SEVERAL WEAK
DISTURBANCES PUSHING THROUGH THE FLOW SAT AFTN THROUGH SUN NIGHT.
THE WARM FRONT WILL CONTINUE TO SLOWLY PUSH NE ON SAT...AS IT
BATTLES THE HIGH THAT WILL HAVE MOVED EAST OVER ONTARIO. PCPN
CHANCES ON SAT WILL LARGELY DEPEND ON HOW FAR N THE FRONT WILL PUSH.
BEST CHANCES LOOK TO BE ON SAT NIGHT INTO SUN...AS THE FRONT MOVES
INTO NRN WI AND FINALLY INTO UPPER MI BY SUN AFTN. THIS WILL PUT THE
BEST WAA FOCUS OVER THE CWA. THERE ARE DECENT MID LEVEL LAPSE
RATES...BUT ELEVATED CAPES ARE NOT TOO IMPRESSIVE...SO HAVE CAPPED
THUNDER TO CHANCES FOR SAT NIGHT INTO SUN. WITH THE CONVECTION
LIKELY TO BE ELEVATED...THE MAIN THREAT WOULD BE SMALL HAIL AND
HEAVY RAIN.
CWA WILL BE UNDER THE WARM SECTOR LATE SUN AFTN AND INTO SUN
NIGHT...WITH MODELS DIVERGING WITH THE HANDLING OF THE LOW HEADING
INTO THE FIRST PART OF NEXT WEEK. 12Z GFS SHOWS THE LOW CONTINUING
NNE INTO SRN CANADA ON SUN NIGHT AND MONDAY WHILE PUSHING COLD FRONT
ACROSS UPPER MI ON MON. 00Z ECMWF ON THE OTHERHAND DISSIPATES THE
LOW OVER THE CWA AND THEN SLOWLY SLIDES IT EAST THROUGH TUES. AFTER
A MORE ACTIVE PERIOD...OVERALL TREND LOOKS TO BE TOWARDS A SLIGHTLY
DRIER/QUIET WEATHER TOWARDS THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 132 AM EDT THU MAY 24 2012
STRONG WINDS AND LLWS REMAIN A CONCERN THROUGHOUT THE FORECAST.
LATEST VAD WIND PROFILE PRODUCT FROM THE MARQUETTE 88D SHOWS 50KT S
WINDS AT 2-3K FEET EARLY THIS MORNING WHICH IS IN LINE WITH LATEST
BUFKIT FORECASTS. UNIDIRECTIONAL FLOW AS STRONG AS 55 TO 60KTS ABOVE
THE BOUNDARY LAYER WILL GRADUALLY DIMINISH THROUGH THE NIGHT AS IT
SHIFTS SLIGHTLY TO THE SW BUT WILL REMAIN 40-48 KTS BY 12Z. DECENT
MIXING WILL RESULT IN VERY GUSTY CONDITIONS AT ALL THREE TAF SITES
AHEAD OF SLOWLY APPROACHING COLD FRONT. HAVE BUMPED WIND GUST SPEEDS
UP A BIT FOR THE DAYTIME HOURS. WIDELY SCATTERED SHOWERS TO CONTINUE
AT IWD THROUGHOUT THE NIGHT WITH A CHANCE OF THUNDERSTORMS THERE BY
DAYBREAK. CONVECTIVE ACTIVITY TO INCREASE THROUGH THE DAYLIGHT HOURS
AS IT SPREADS SLOWLY ACROSS THE REGION...REACHING CMX BY 18Z AND SAW
AROUND 0Z FRIDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ALONG
THE COLD FRONT DURING THE AFTERNOON AND EVENING WITH CONVECTION
LASTING THROUGH THE END OF THE TAF FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT WED MAY 23 2012
LOW PRESSURE OVER S MANITOBA WILL PUSH INTO ONTARIO TONIGHT AND
THURSDAY...AS AN ADDITIONAL LOW MOVES FROM THE CENTRAL PLAINS TO W
LS FRIDAY AFTERNOON. EXPECT THE LOW TO CONTINUE A NE TRACK ACROSS
ONTARIO THROUGH FRIDAY...WITH A TROUGH LINGERING ACROSS LAKE
SUPERIOR. STRENGTHENING S WINDS WILL PREVAIL AHEAD OF THIS SYSTEM
TONIGHT THROUGH THURSDAY. WITH A STABLE TEMPERATURE PROFILE THE
STRONGEST WINDS...EXPECT THE STRONGEST ACROSS THE TALLER OBSERVING
PLATFORMS ACROSS CENTRAL LAKE SUPERIOR.
HIGH PRESSURE OVER CENTRAL CANADA FRIDAY NIGHT WILL SLIDE ACROSS
ONTARIO SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON SUNDAY. AS A
RESULT...A RIDGE WILL SLIDE ACROSS LS SATURDAY...WITH LIGHTER WINDS
TAKING HOLD. A LOW ACROSS THE CENTRAL PLAINS WILL FILL ACROSS MN
SUNDAY INTO SUNDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY FROM 1 PM EDT /NOON CDT/ THIS AFTERNOON TO 8 PM
EDT /7 PM CDT/ THIS EVENING FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR LSZ263-
264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...SRF
AVIATION...RJT
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
133 AM EDT THU MAY 24 2012
.SYNOPSIS...
ISSUED AT 427 PM EDT WED MAY 23 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
OVER THE NW CONUS AND A RIDGE FROM THE CNTRL GREAT LAKES INTO NRN
ONTARIO RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE UPPER MS
VALLEY AND LAKE SUPERIOR. AT THE SFC...SRLY WINDS WERE INCREASING
ACROSS THE REGION AHEAD A COLD FRONT EXTENDING THROUGH THE ERN
DAKOTAS FROM LOW PRESSURE OVER SRN MANITOBA. AN AREA OF TSRA WAS
MOVING NE THROUGH N CNTRL MN SUPPORTED A SHRTWV NEAR THE NOSE OS
STRONG 925-850 MB THETA-E ADVECTION. OVER UPPER MI...VIS LOOP AND
SFC OBS SHOWED CONSIDERABLE HIGH CLOUDS IN THE BROAD WAA PATTERN
AHEAD OF THE FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
TONIGHT...AS A SHRTWV OVER NW MN LIFTS TO THE NE AND
THE NEXT SIGNIFICANT UPSTREAM SHRTWV OVER NEVADA ROTATES THROUGH
THE WRN TROF...ANOTHER SFC LOW WILL DEVELOP IN THE PLAINS AND
MOVE NNEWD ON COLD FNT ATTENDANT TO FIRST SFC LO DRIFTING THRU NW
ONTARIO. EXPECT THAT THE GREATEST CHANCE FOR SHRA/TSRA WILL REMAIN
CLOSER TO THE FRONT AND NEAR THE AXIS OF GREATER
MOISTURE/INSTABILITY OVER MN AND FAVORABLE UPPER LEVEL DIV WITH THE
RIGHT ENTRANCE OF THE JET OVER NW ONTARIO. SO...THE NAM/REGIONAL
GEM/ECMWF WERE PREFERRED WITH THE SHRA/TSRA PLACEMENT COMPARED TO
THE GFS WHICH SEEMED OVERLY AGGRESSIVE IN PUSHING THE PCPN TO THE
EAST.
THURSDAY...THE MAIN SHRTWV LIFTS OUT OF THE PLAINS TO THE UPPER MS
VALLEY SUPPORTING A CONSOLIDATED SFC LOW TO NEAR KDLH BY 00Z/FRI.
GIVEN THE STRENGTHENING DYNAMICS AGAIN TO THE WEST...CONTINUED TO
DELAY THE EASTWARD PROGRESSION OF THE SHRA/TSRA INTO UPPER MI TIL
MAINLY LATE IN THE DAY. MLCAPE VALUES TO AROUND 1K J/KG WITH
AFTERNOON HEATING AND SFC DEWPOINTS NEAR 60 WILL SUPPORT TSRA
CHANCES FROM IWD-CMX...MAINLY AFT 21Z. WITH INVERTED V LOOK TO THE
SOUNDINGS AND VERY STRONG MAINLY UNIDIRECTIONAL WIND FIELD (700 MB
WINDS TO NEAR 70KT)...EXPECT THAT DAMAGING WINDS WILL BE THE MAIN
HAZARD WITH ANY TSRA.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 427 PM EDT WED MAY 23 2012
MAIN CONCERN FOR THE LONG TERM PERIOD IS THE SEVERE WEATHER
POTENTIAL AT THE BEGINNING OF THE PERIOD.
STATIONARY FRONT WILL BE SETUP OVER WRN LK SUPERIOR...WHILE A FAIRLY
POTENT SHORTWAVE PUSHING NE ACROSS AT LEAST THE WRN HALF OF THE CWA
THURS NIGHT. THIS WILL LEAD TO ONGOING CYCLOGENESIS OVER NW WI
DURING THE LATE AFTERNOON AND THE LOW MOVING NNE ACROSS WRN LK
SUPERIOR DURING THE EVENING. EXPECT THUNDERSTORMS TO BE ONGOING
OVER NW WI AND FAR WRN LK SUPERIOR AT THE START OF THE PERIOD AND
THEN MOVE E AND NE AS THE COLD FRONT PUSHES THROUGH THE CWA DURING
THE NIGHT.
WITH THE STRONG WINDS ALOFT AND THE CYCLOGENESIS...FEEL THAT THERE
IS A DECENT CHANCE OF SEVERE WEATHER OVER THE WRN HALF OF THE CWA
TOMORROW EVENING. THERE IS A VERY THIN CORRIDOR OF MLCAPE VALUES
APPROACHING 500-1000 J/KG OVER THE WRN THIRD OF THE CWA AND
INSTABILITY MAY BE THE MAIN LIMITING FACTOR AS STORMS MOVE INTO THE
CWA. CAPE FAIRLY SKINNY...NCAPE VALUES AROUND 0.1...SO DON/T EXPECT
MUCH MORE THAN MARGINALLY SEVERE HAIL.
WIND APPEARS TO BE BIGGEST THREAT WITH THE STORMS. INVERTED V LOOK
TO THE SOUNDINGS OVER THE WEST AND DCAPE VALUES OF 600-800 J/KG.
STRONG WINDS ALOFT...APPROACHING 70-80KTS AT H700 AND
40-50KTS JUST A COUPLE HUNDRED FEET ABOVE THE SFC...WILL BE
AIDED BY A POCKET OF DRY H700-500 AIR AND STEEPER LAPSE RATES.
THIS...COMBINED WITH STORM MOTION TO THE NNE AT 65-70KTS ALL POINT
TO THE POTENTIAL FOR DAMAGING WINDS WHERE THUNDERSTORMS...AND
POTENTIALLY EVEN SHOWERS OCCUR. WITH THE LOW DEVELOPING ALONG THE
FRONT POTENTIALLY AFFECTING THE LLVL WIND FIELD...COULD SEE SOME
LLVL BACKING OF THE WINDS AND PRODUCE SOME ROTATING UPDRAFTS AND
SUPERCELLS...ESPECIALLY OVER NW WI. BUT THE EXPECTED DRY LLVL AIR
HELPING PRODUCE AN INVERTED V AND LCL HEIGHTS TOWARDS 3-3.5KFT
SHOULD LIMIT TORNADO POTENTIAL THIS FAR N.
CURRENT THOUGHT IS BEST CHANCES FOR SEVERE SHOULD BE FROM
BARAGA/IRON COUNTIES AND WEST...BUT WITH THE STORM MOTIONS...COULD
POTENTIALLY AFFECT MARQUETTE/DICKINSON/MENOMINEE COUNTIES BEFORE
HEADING OVER LK SUPERIOR. ADDED DAMAGING WIND THREAT TO THE GRIDS
AND MENTIONED IN THE HWO. THIS MATCHES UP WELL WHERE SPC HAS A
SLIGHT RISK...WITH HATCHED AREA JUST TO THE SW OF THE CWA.
AS THE LOW QUICKLY LIFTS NE...EXPECT BEST FORCING TO QUICKLY
DEPART OVERNIGHT AND PULL FORCING WITH IT. IN ADDITION...AS THE COLD
FRONT PUSHES EAST INTO THE CNTRL/ERN CWA...THE CAPPING BECOMES
STRONGER. WITH THE COMBINATION OF LOOSING FORCING AND MORE
UNFAVORABLE ENVIRONMENT...EXPECT THE SHOWERS/THUNDERSTORMS TO
DIMINISH AS THEY MOVE INTO THE CNTRL/ERN CWA. 09Z SREF ALSO SHOWING
THIS DIMINISHING TREND IN THE 3HR CALIBRATED THUNDERSTORM PROBS...AS
THE SHOWERS/THUNDERSTORMS PUSH TO THE NE OVER LK SUPERIOR DURING THE
OVERNIGHT HOURS.
EXPECT GUSTY SE WINDS IN THE EVENING AHEAD OF THE LOW AND OVER THE
KEWEENAW OVERNIGHT BEHIND THE LOW/FRONT. BUMPED UP WINDS
SIGNIFICANTLY OVER THE KEWEENAW BEHIND THE LOW AND FRONT...WITH THE
STRONG WINDS JUST ABOVE THE SFC /NAM SHOWING 60KTS AT 1.5KFT/. IN
ADDITION...GOOD ISALLOBARIC COMPONENT TO THE WINDS OVER THE WEST
OVERNIGHT WITH THE INTENSIFYING LOW PUSHING NE. ONLY CONCERN FOR
GOING MORE THAN 30-35KTS AT THIS POINT IS AFFECT OF COOLER WATER
TEMPS...BUT THAT MAY NOT HAVE MUCH EFFECT OVER THE HIGHER TERRAIN.
FRI...GUSTY WRLY WINDS...30-35KTS...IN THE MORNING BEHIND THE LOW.
DRIER AIR MOVING IN AND H700 CAP SHOULD LIMIT DEVELOPMENT EVEN WITH
WEAK MID-LVL WAVE MOVING THROUGH. DEEP MOISTURE IS LIMITED AND ML/MU
CAPE VALUES ARE BELOW 100 JKG WOULD LEAD TO LITTLE/NO PCPN CHANCES.
LATEST NAM RUN HAS BACKED OFF ON PCPN AND WILL FOLLOW SUIT WITH
REMOVING SLIGHT CHANCES. WILL KEEP SKIES PARTLY/MOSTLY CLOUDY DURING
THE AFTN WITH EXPECTED DIURNAL CU DEVELOPMENT.
MIXING TO H750 WOULD YIELD HIGHS IN THE 70S...WITH THE HIGHEST
VALUES IN THE FAVORED DOWNSLOPE AREAS OF THE CNTRL. WITH THE GUSTY
WINDS AND DEEPER MIXING INTO THE LIMITED MOISTURE ALOFT...EXPECT RH
VALUES TO FALL TO 30 PERCENT. FIRE WX CONCERNS MAINLY OVER THE
CNTRL...WHERE LESS RAIN IS EXPECTED ON THURS NIGHT.
FRI NIGHT...WEAK HIGH PRESSURE RIDGE FROM HIGH JUST N OF MN. SFC LOW
DEVELOPING IN THE CNTRL PLAINS IN RESPONSE TO DEEP UPPER TROUGH
OVER THE WRN CONUS WILL BEGIN TO PUSH A WARM FRONT N TOWARDS THE
UPPER GREAT LAKES LATE FRI NIGHT. COULD PRODUCE A FEW SHOWERS
TOWARDS THE WI BORDER LATE.
CWA WILL BE ON THE E SIDE OF THE UPPER RIDGE AXIS STRETCHING FROM
THE OHIO VALLEY TO LK WINNIPEG UNTIL SUN NIGHT. STILL SEVERAL WEAK
DISTURBANCES PUSHING THROUGH THE FLOW SAT AFTN THROUGH SUN NIGHT.
THE WARM FRONT WILL CONTINUE TO SLOWLY PUSH NE ON SAT...AS IT
BATTLES THE HIGH THAT WILL HAVE MOVED EAST OVER ONTARIO. PCPN
CHANCES ON SAT WILL LARGELY DEPEND ON HOW FAR N THE FRONT WILL PUSH.
BEST CHANCES LOOK TO BE ON SAT NIGHT INTO SUN...AS THE FRONT MOVES
INTO NRN WI AND FINALLY INTO UPPER MI BY SUN AFTN. THIS WILL PUT THE
BEST WAA FOCUS OVER THE CWA. THERE ARE DECENT MID LEVEL LAPSE
RATES...BUT ELEVATED CAPES ARE NOT TOO IMPRESSIVE...SO HAVE CAPPED
THUNDER TO CHANCES FOR SAT NIGHT INTO SUN. WITH THE CONVECTION
LIKELY TO BE ELEVATED...THE MAIN THREAT WOULD BE SMALL HAIL AND
HEAVY RAIN.
CWA WILL BE UNDER THE WARM SECTOR LATE SUN AFTN AND INTO SUN
NIGHT...WITH MODELS DIVERGING WITH THE HANDLING OF THE LOW HEADING
INTO THE FIRST PART OF NEXT WEEK. 12Z GFS SHOWS THE LOW CONTINUING
NNE INTO SRN CANADA ON SUN NIGHT AND MONDAY WHILE PUSHING COLD FRONT
ACROSS UPPER MI ON MON. 00Z ECMWF ON THE OTHERHAND DISSIPATES THE
LOW OVER THE CWA AND THEN SLOWLY SLIDES IT EAST THROUGH TUES. AFTER
A MORE ACTIVE PERIOD...OVERALL TREND LOOKS TO BE TOWARDS A SLIGHTLY
DRIER/QUIET WEATHER TOWARDS THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 132 AM EDT THU MAY 24 2012
STRONG WINDS AND LLWS REMAIN A CONCERN THROUGHOUT THE FORECAST.
LATEST VAD WIND PROFILE PRODUCT FROM THE MARQUETTE 88D SHOWS 50KT S
WINDS AT 2-3K FEET EARLY THIS MORNING WHICH IS IN LINE WITH LATEST
BUFKIT FORECASTS. UNIDIRECTIONAL FLOW AS STRONG AS 55 TO 60KTS ABOVE
THE BOUNDARY LAYER WILL GRADUALLY DIMINISH THROUGH THE NIGHT AS IT
SHIFTS SLIGHTLY TO THE SW BUT WILL REMAIN 40-48 KTS BY 12Z. DECENT
MIXING WILL RESULT IN VERY GUSTY CONDITIONS AT ALL THREE TAF SITES
AHEAD OF SLOWLY APPROACHING COLD FRONT. HAVE BUMPED WIND GUST SPEEDS
UP A BIT FOR THE DAYTIME HOURS. WIDELY SCATTERED SHOWERS TO CONTINUE
AT IWD THROUGHOUT THE NIGHT WITH A CHANCE OF THUNDERSTORMS THERE BY
DAYBREAK. CONVECTIVE ACTIVITY TO INCREASE THROUGH THE DAYLIGHT HOURS
AS IT SPREADS SLOWLY ACROSS THE REGION...REACHING CMX BY 18Z AND SAW
AROUND 0Z FRIDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ALONG
THE COLD FRONT DURING THE AFTERNOON AND EVENING WITH CONVECTION
LASTING THROUGH THE END OF THE TAF FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT WED MAY 23 2012
LOW PRESSURE OVER S MANITOBA WILL PUSH INTO ONTARIO TONIGHT AND
THURSDAY...AS AN ADDITIONAL LOW MOVES FROM THE CENTRAL PLAINS TO W
LS FRIDAY AFTERNOON. EXPECT THE LOW TO CONTINUE A NE TRACK ACROSS
ONTARIO THROUGH FRIDAY...WITH A TROUGH LINGERING ACROSS LAKE
SUPERIOR. STRENGTHENING S WINDS WILL PREVAIL AHEAD OF THIS SYSTEM
TONIGHT THROUGH THURSDAY. WITH A STABLE TEMPERATURE PROFILE THE
STRONGEST WINDS...EXPECT THE STRONGEST ACROSS THE TALLER OBSERVING
PLATFORMS ACROSS CENTRAL LAKE SUPERIOR.
HIGH PRESSURE OVER CENTRAL CANADA FRIDAY NIGHT WILL SLIDE ACROSS
ONTARIO SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON SUNDAY. AS A
RESULT...A RIDGE WILL SLIDE ACROSS LS SATURDAY...WITH LIGHTER WINDS
TAKING HOLD. A LOW ACROSS THE CENTRAL PLAINS WILL FILL ACROSS MN
SUNDAY INTO SUNDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...RJT
MARINE...JLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1246 AM CDT THU MAY 24 2012
.AVIATION UPDATE...LINE OF CONVECTION TO THE WEST OF KGRI AS
EXTENDED SOUTHEAST AND INTENSIFIED...WITH WIND GUSTS NEAR OR ABOVE
50KTS NOW POSSIBLE AT KGRI THROUGH THE NEXT HOUR.
&&
.PREV DISCUSSION... /ISSUED 1226 AM CDT THU MAY 24 2012/
AVIATION...06Z KGRI TAF. PREVAILING VFR CONDITIONS TO
CONTINUE...WITH TEMPORARY MVFR CONDITIONS POSSIBLE 07Z-11Z.
CONVECTIVE ACTIVITY WEST OF KGRI MAY WORK IN LATER TONIGHT...BUT
PROBABLY NOT UNTIL AFTER 07Z. SURFACE WINDS TO REMAIN FROM THE
NORTH FOR THE MOST PART. MINIMAL VISIBILITY RESTRICTIONS WILL BE
POSSIBLE IN PRECIPITATION...BUT WILL OTHERWISE REMAIN UNRESTRICTED
DURING THE TAF PERIOD.
PREV DISCUSSION... /ISSUED 1104 PM CDT WED MAY 23 2012/
UPDATE...KUEX INDICATES CONVECTION SPREADING IN AERIAL COVERAGE
ACROSS THE NORTHWESTERN ONE-THIRD OF THE CWA. SHORT TERM GUIDANCE
CONTINUES TO SUGGEST THIS A TREND WHICH WILL CONTINUE. DEEP LAYER
MUCAPE VALUES NEAR 1000J/KG AND DEEP LAYER BULK SHEAR NEAR 50KTS
WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL. A NEW SEVERE
THUNDERSTORM WATCH HAS BEEN ISSUED WHICH COVERS THE ENTIRE CWA
THROUGH 10Z. FORECAST HAS BEEN UPDATED TO INCLUDE THIS NEW SEVERE
THUNDERSTORM WATCH.
PREV DISCUSSION... /ISSUED 949 PM CDT WED MAY 23 2012/
UPDATE...EVENING UPPER AIR ANALYSIS INDICATES TROUGHING OVER THE
WESTERN CONUS WITH A RIDGE OVER THE EAST. MID AND UPPER LEVEL JET
ENERGY EXTENDS FROM THE WEST-CENTRAL CONUS...SOUTHEAST INTO THE
MID ROCKY MOUNTAIN RANGE AND THEN NORTHEAST ACROSS THE CENTRAL
PLAINS. A ~100KT UPPER LEVEL JET STREAK AND A ~70KT MID LEVEL JET
STREAK IS NOTED ACROSS THE WEST-CENTRAL CONUS AND BEGINNING TO
PUSH INTO THE CENTRAL PLAINS. WATER VAPOR IMAGERY SHOWS A MID
LEVEL SHORT WAVE APPROACHING THE MID ROCKY MOUNTAIN RANGE. AT THE
SURFACE A COLD FRONT EXTENDS FROM NEAR KOMA...TO NEAR KCNK...TO
NEAR KDDC. LOW LEVEL FLOW IS FROM THE THE NORTHEAST ACROSS MUCH OF
OUR CWA AS A RESULT...ALTHOUGH LOCATIONS FROM THAYER COUNTY TO
MITCHELL COUNTY...STILL AHEAD OF THE LOW LEVEL BAROCLINIC
ZONE...REMAIN FROM THE SOUTHEAST. KUEX SHOWS A THIN LINE OF
CONVECTION...ALONG THE LOW LEVEL BAROCLINIC ZONE...EXTENDING FROM
THAYER COUNTY TO MITCHELL COUNTY...BUT ADDITIONAL CONVECTION IS
NOT FIRING FARTHER NORTHWEST ACROSS MUCH OF THE REST OF THE CWA.
SHORT TERM GUIDANCE SUGGESTS SURFACE-BASED CONVECTION WILL REMAIN
POSSIBLE ALONG THE LOW LEVEL BAROCLINIC ZONE THROUGH 04Z OR
SO...HOWEVER THIS ACTIVITY SHOULD DIMINISH THEREAFTER AS DIABATIC
HEATING IS COMPLETELY LOST AND REMNANT FORCING ALONG THE
BAROCLINIC ZONE REMAINS FAIRLY WEAK. THE INDIRECT THERMAL
CIRCULATION WITHIN THE LEFT-FRONT QUAD OF THE APPROACHING MID
LEVEL JET STREAK...ALONG WITH CONTINUALLY INCREASING OMEGA AHEAD
OF THE MID LEVEL SHORT WAVE...WILL CONTINUE TO PROMOTE
PRECIPITATION ACROSS MUCH OF THE CWA THROUGH THE OVERNIGHT HOURS.
AT THIS TIME IT APPEARS THE BULK OF THE FORCING OVERNIGHT WILL BE
RELEGATED TO THE NORTHERN HALF OF THE CWA WHICH IS WHERE MOST OF
THE PRECIPITATION WILL BE REALIZED. SPC MESO-ANALYSIS INDICATES
DEEP LAYER MUCAPE VALUES OF AROUND 1000J/KG CURRENTLY IN EXISTENCE
ACROSS MUCH OF THE CWA...WITH DEEP LAYER SHEAR OF AROUND 60KTS.
THE COMBINATION OF MODERATE INSTABILITY AND VERY STRONG DEEP LAYER
SHEAR WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL ACROSS MUCH
OF THE CWA THROUGH EARLY MORNING THURSDAY.
WENT AHEAD AND UPDATED THE FORECAST WITH SLIGHT CHANGES MADE TO
HOURLY GIRDS TO BETTER REFLECT CURRENT TRENDS...ESPECIALLY
REGARDING CLOUD COVER. CURRENT POPS ACROSS NORTHERN PORTIONS OF THE
CWA LOOK RIGHT ON FOR TONIGHT AND THUS RAIN CHANCES WERE LEFT AS IS.
PREV DISCUSSION... /ISSUED 419 PM CDT WED MAY 23 2012/
UPDATE...SENT AN UPDATE TO THE FORECAST TO INCLUDE SEVERE
THUNDERSTORM WATCH 293 FOR PORTIONS OF THE FORECAST AREA THROUGH
11 PM CDT. THE GREATEST POTENTIAL FOR ANY SEVERE STORMS WILL
REMAIN WITH AND ALONG EITHER SIDE OF A SLOWLY PROGRESSING COLD
FRONT...WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY
CONCERNS WITH ANY STORMS THAT DO DEVELOP.
PREV DISCUSSION... /ISSUED 400 PM CDT WED MAY 23 2012/
SHORT TERM...A FAIRLY ACTIVE START TO THE FORECAST IS EXPECTED
THIS EVENING AS A COLD FRONT SLOWLY MAKES ITS WAY ACROSS SOUTH
CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...WITH AN ASSOCIATED MID
LEVEL LOW PRESSURE SYSTEM TO THE WEST EXPECTED TO HELP BRING SOME
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE
FORECAST AREA DURING THE OVERNIGHT HOURS TONIGHT.
SHORT TERM MODELS ARE IN MODERATE DISAGREEMENT WITH INITIATION OF
CONVECTION ALONG A PASSING COLD FRONT...CURRENTLY DRAPED FROM NEAR
NORFOLK...ACROSS GRAND ISLAND...SOUTH WESTWARD TOWARDS HOLDREGE.
THIS FRONT HAS BEEN VERY SLOW TO WORK ITS WAY ACROSS THE FORECAST
AREA THIS AFTERNOON...AND SO FAR HAS YET TO PRODUCE ENOUGH FORCING
TO BREAK LOW LEVEL CAP. 12Z NAM AND WRF BOTH DID TRY AND INITIATE
CONVECTION...BUT 18Z NAM AND LATEST HRRR BOTH HOLD OFF ANY
WIDESPREAD SHOWER OR THUNDERSTORM ACTIVITY TILL FORCING FROM MID
LEVEL LOW TO OUR WEST APPROACHES CENTRAL NEBRASKA AROUND MIDNIGHT.
THAT BEING SAID...INGREDIENTS ARE IN PLACE...AS LATEST MESO
ANALYSIS SHOWS A FINGER OF 2000+ J/KG OF CAPE ACROSS THE LOCAL
AREA NEAR THE SLOWLY PROGRESSING FRONT...AND LITTLE INHIBITION AS
WELL AS DEVELOPING CU FIELD IN SATELLITE. PER CONSENSUS AMONG
MODELS...DID BACK OFF ON INITIATION OF CONVECTION THIS
AFTERNOON...BUT INSERTED MENTION OF SEVERE STORMS AFTER 00Z...AS
COMBINATION OF SHEAR AND INSTABILITY SHOULD BE SUFFICIENT FOR SOME
SUPERCELLS TO DEVELOP IF INITIATION CAN BE REALIZED NEAR THE
FRONT.
BEHIND THE FRONT...AS THE MID LEVEL SHORTWAVE APPROACHES THE
REGION...BROADER SCALE FORCING SHOULD BE AMPLE ENOUGH TO DEVELOP
WIDESPREAD CONVECTION ACROSS THE LOCAL AREA BY AROUND
MIDNIGHT...CONTINUING INTO THE OVERNIGHT HOURS...SO THE POTENTIAL
FOR SEVERE HAIL AND STRONG WINDS REMAIN A CONCERN.
THEREAFTER...THE ATMOSPHERE SHOULD BEGIN TO STABILIZE BEHIND THE
DEPARTING MID LEVEL WAVE...WITH A SMALL CHANCE FOR SHOWERS AND AN
ISOLATED THUNDERSTORM CONTINUING INTO THE AFTERNOON HOURS WITH
NEAR TO SLIGHTLY BELOW SEASONAL TEMPERATURES EXPECTED DURING THE
AFTERNOON.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MOST OF THE
PERIOD AND TEMPERATURES.
ZONAL TO SOUTHWEST FLOW GIVES WAY TO NORTHWEST FLOW. THERE ARE
SEVERAL WAVES THAT MOVE THROUGH THE AREA DURING THE PERIOD. THE
FIRST WAVE MOVES INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THERE
WILL BE A CHANCE FOR SOME THUNDERSTORMS. ON FRIDAY A SURFACE LOW
DEVELOPING IN KANSAS WILL LIFT A WARM FRONT NORTH INTO THE FORECAST
AREA. WITH THE FRONT MOVING THROUGH AND THE ANOTHER UPPER WAVE
MOVING INTO THE AREA THERE IS A BETTER CHANCE FOR THUNDERSTORMS.
SOME OF THESE STORMS COULD BE STRONG TO SEVERE.
SATURDAY AND SATURDAY NIGHT THERE ARE WEAK WAVES THAT MOVES THROUGH
BUT LITTLE IN THE WAY TO GET THINGS STARTED SO ANY PRECIPITATION
WILL BE SPOTTY. THE NEXT CHANCE FOR SOME THUNDERSTORMS WILL BE
SUNDAY INTO SUNDAY NIGHT. ANOTHER STRONGER WAVE MOVES INTO THE AREA
AND A COLD FRONT MOVES THROUGH THE AREA SUNDAY AFTERNOON AND
EVENING. THUNDERSTORMS WILL DEVELOP ALONG THE FRONT AS IT MOVES
THROUGH. SOME OF THESE COULD BE SEVERE.
MONDAY AND MONDAY NIGHT THE UPPER WAVE MOVES TO THE EAST AND A
SURFACE HIGH PRESSURE MOVES INTO THE AREA...KEEPING THINGS DRY.
AGAIN TUESDAY INTO TUESDAY NIGHT THERE ARE A FEW WEAK UPPER LEVEL
WAVES THAT MOVE INTO THE PLAINS. MODELS HAVE SOME FAIRLY SPOTTY
PRECIPITATION AROUND THE AREA WITH THESE UPPER LEVEL WAVES. THE GFS
HAS MORE PRECIPITATION AROUND THAN THE ECMWF DOES.
TEMPERATURES WILL BE SOMEWHAT VARIABLE THROUGH THE WEEK. WITH CLOUDS
AROUND ON FRIDAY THE TEMPERATURES WILL BE A BIT COOLER...WARMING
AFTER THE WARM FRONT LIFTS TO THE NORTH FOR SATURDAY AND SUNDAY THEN
COOLING AGAIN AS THE COOL FRONT MOVE THROUGH MONDAY AND TUESDAY AND
COOLING MORE AFTER THE FRONT MOVES THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION UPDATE/AVIATION/1105 UPDATE/949 UPDATE...BRYANT
419 UPDATE/SHORT TERM...ROSSI
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1226 AM CDT THU MAY 24 2012
.AVIATION...06Z KGRI TAF. PREVAILING VFR CONDITIONS TO
CONTINUE...WITH TEMPORARY MVFR CONDITIONS POSSIBLE 07Z-11Z.
CONVECTIVE ACTIVITY WEST OF KGRI MAY WORK IN LATER TONIGHT...BUT
PROBABLY NOT UNTIL AFTER 07Z. SURFACE WINDS TO REMAIN FROM THE
NORTH FOR THE MOST PART. MINIMAL VISIBILITY RESTRICTIONS WILL BE
POSSIBLE IN PRECIPITATION...BUT WILL OTHERWISE REMAIN UNRESTRICTED
DURING THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1104 PM CDT WED MAY 23 2012/
UPDATE...KUEX INDICATES CONVECTION SPREADING IN AERIAL COVERAGE
ACROSS THE NORTHWESTERN ONE-THIRD OF THE CWA. SHORT TERM GUIDANCE
CONTINUES TO SUGGEST THIS A TREND WHICH WILL CONTINUE. DEEP LAYER
MUCAPE VALUES NEAR 1000J/KG AND DEEP LAYER BULK SHEAR NEAR 50KTS
WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL. A NEW SEVERE
THUNDERSTORM WATCH HAS BEEN ISSUED WHICH COVERS THE ENTIRE CWA
THROUGH 10Z. FORECAST HAS BEEN UPDATED TO INCLUDE THIS NEW SEVERE
THUNDERSTORM WATCH.
PREV DISCUSSION... /ISSUED 949 PM CDT WED MAY 23 2012/
UPDATE...EVENING UPPER AIR ANALYSIS INDICATES TROUGHING OVER THE
WESTERN CONUS WITH A RIDGE OVER THE EAST. MID AND UPPER LEVEL JET
ENERGY EXTENDS FROM THE WEST-CENTRAL CONUS...SOUTHEAST INTO THE
MID ROCKY MOUNTAIN RANGE AND THEN NORTHEAST ACROSS THE CENTRAL
PLAINS. A ~100KT UPPER LEVEL JET STREAK AND A ~70KT MID LEVEL JET
STREAK IS NOTED ACROSS THE WEST-CENTRAL CONUS AND BEGINNING TO
PUSH INTO THE CENTRAL PLAINS. WATER VAPOR IMAGERY SHOWS A MID
LEVEL SHORT WAVE APPROACHING THE MID ROCKY MOUNTAIN RANGE. AT THE
SURFACE A COLD FRONT EXTENDS FROM NEAR KOMA...TO NEAR KCNK...TO
NEAR KDDC. LOW LEVEL FLOW IS FROM THE THE NORTHEAST ACROSS MUCH OF
OUR CWA AS A RESULT...ALTHOUGH LOCATIONS FROM THAYER COUNTY TO
MITCHELL COUNTY...STILL AHEAD OF THE LOW LEVEL BAROCLINIC
ZONE...REMAIN FROM THE SOUTHEAST. KUEX SHOWS A THIN LINE OF
CONVECTION...ALONG THE LOW LEVEL BAROCLINIC ZONE...EXTENDING FROM
THAYER COUNTY TO MITCHELL COUNTY...BUT ADDITIONAL CONVECTION IS
NOT FIRING FARTHER NORTHWEST ACROSS MUCH OF THE REST OF THE CWA.
SHORT TERM GUIDANCE SUGGESTS SURFACE-BASED CONVECTION WILL REMAIN
POSSIBLE ALONG THE LOW LEVEL BAROCLINIC ZONE THROUGH 04Z OR
SO...HOWEVER THIS ACTIVITY SHOULD DIMINISH THEREAFTER AS DIABATIC
HEATING IS COMPLETELY LOST AND REMNANT FORCING ALONG THE
BAROCLINIC ZONE REMAINS FAIRLY WEAK. THE INDIRECT THERMAL
CIRCULATION WITHIN THE LEFT-FRONT QUAD OF THE APPROACHING MID
LEVEL JET STREAK...ALONG WITH CONTINUALLY INCREASING OMEGA AHEAD
OF THE MID LEVEL SHORT WAVE...WILL CONTINUE TO PROMOTE
PRECIPITATION ACROSS MUCH OF THE CWA THROUGH THE OVERNIGHT HOURS.
AT THIS TIME IT APPEARS THE BULK OF THE FORCING OVERNIGHT WILL BE
RELEGATED TO THE NORTHERN HALF OF THE CWA WHICH IS WHERE MOST OF
THE PRECIPITATION WILL BE REALIZED. SPC MESO-ANALYSIS INDICATES
DEEP LAYER MUCAPE VALUES OF AROUND 1000J/KG CURRENTLY IN EXISTENCE
ACROSS MUCH OF THE CWA...WITH DEEP LAYER SHEAR OF AROUND 60KTS.
THE COMBINATION OF MODERATE INSTABILITY AND VERY STRONG DEEP LAYER
SHEAR WILL CONTINUE TO PROMOTE A THREAT OF LARGE HAIL ACROSS MUCH
OF THE CWA THROUGH EARLY MORNING THURSDAY.
WENT AHEAD AND UPDATED THE FORECAST WITH SLIGHT CHANGES MADE TO
HOURLY GIRDS TO BETTER REFLECT CURRENT TRENDS...ESPECIALLY
REGARDING CLOUD COVER. CURRENT POPS ACROSS NORTHERN PORTIONS OF THE
CWA LOOK RIGHT ON FOR TONIGHT AND THUS RAIN CHANCES WERE LEFT AS IS.
PREV DISCUSSION... /ISSUED 419 PM CDT WED MAY 23 2012/
UPDATE...SENT AN UPDATE TO THE FORECAST TO INCLUDE SEVERE
THUNDERSTORM WATCH 293 FOR PORTIONS OF THE FORECAST AREA THROUGH
11 PM CDT. THE GREATEST POTENTIAL FOR ANY SEVERE STORMS WILL
REMAIN WITH AND ALONG EITHER SIDE OF A SLOWLY PROGRESSING COLD
FRONT...WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY
CONCERNS WITH ANY STORMS THAT DO DEVELOP.
PREV DISCUSSION... /ISSUED 400 PM CDT WED MAY 23 2012/
SHORT TERM...A FAIRLY ACTIVE START TO THE FORECAST IS EXPECTED
THIS EVENING AS A COLD FRONT SLOWLY MAKES ITS WAY ACROSS SOUTH
CENTRAL NEBRASKA AND NORTH CENTRAL KANSAS...WITH AN ASSOCIATED MID
LEVEL LOW PRESSURE SYSTEM TO THE WEST EXPECTED TO HELP BRING SOME
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE
FORECAST AREA DURING THE OVERNIGHT HOURS TONIGHT.
SHORT TERM MODELS ARE IN MODERATE DISAGREEMENT WITH INITIATION OF
CONVECTION ALONG A PASSING COLD FRONT...CURRENTLY DRAPED FROM NEAR
NORFOLK...ACROSS GRAND ISLAND...SOUTH WESTWARD TOWARDS HOLDREGE.
THIS FRONT HAS BEEN VERY SLOW TO WORK ITS WAY ACROSS THE FORECAST
AREA THIS AFTERNOON...AND SO FAR HAS YET TO PRODUCE ENOUGH FORCING
TO BREAK LOW LEVEL CAP. 12Z NAM AND WRF BOTH DID TRY AND INITIATE
CONVECTION...BUT 18Z NAM AND LATEST HRRR BOTH HOLD OFF ANY
WIDESPREAD SHOWER OR THUNDERSTORM ACTIVITY TILL FORCING FROM MID
LEVEL LOW TO OUR WEST APPROACHES CENTRAL NEBRASKA AROUND MIDNIGHT.
THAT BEING SAID...INGREDIENTS ARE IN PLACE...AS LATEST MESO
ANALYSIS SHOWS A FINGER OF 2000+ J/KG OF CAPE ACROSS THE LOCAL
AREA NEAR THE SLOWLY PROGRESSING FRONT...AND LITTLE INHIBITION AS
WELL AS DEVELOPING CU FIELD IN SATELLITE. PER CONSENSUS AMONG
MODELS...DID BACK OFF ON INITIATION OF CONVECTION THIS
AFTERNOON...BUT INSERTED MENTION OF SEVERE STORMS AFTER 00Z...AS
COMBINATION OF SHEAR AND INSTABILITY SHOULD BE SUFFICIENT FOR SOME
SUPERCELLS TO DEVELOP IF INITIATION CAN BE REALIZED NEAR THE
FRONT.
BEHIND THE FRONT...AS THE MID LEVEL SHORTWAVE APPROACHES THE
REGION...BROADER SCALE FORCING SHOULD BE AMPLE ENOUGH TO DEVELOP
WIDESPREAD CONVECTION ACROSS THE LOCAL AREA BY AROUND
MIDNIGHT...CONTINUING INTO THE OVERNIGHT HOURS...SO THE POTENTIAL
FOR SEVERE HAIL AND STRONG WINDS REMAIN A CONCERN.
THEREAFTER...THE ATMOSPHERE SHOULD BEGIN TO STABILIZE BEHIND THE
DEPARTING MID LEVEL WAVE...WITH A SMALL CHANCE FOR SHOWERS AND AN
ISOLATED THUNDERSTORM CONTINUING INTO THE AFTERNOON HOURS WITH
NEAR TO SLIGHTLY BELOW SEASONAL TEMPERATURES EXPECTED DURING THE
AFTERNOON.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MOST OF THE
PERIOD AND TEMPERATURES.
ZONAL TO SOUTHWEST FLOW GIVES WAY TO NORTHWEST FLOW. THERE ARE
SEVERAL WAVES THAT MOVE THROUGH THE AREA DURING THE PERIOD. THE
FIRST WAVE MOVES INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THERE
WILL BE A CHANCE FOR SOME THUNDERSTORMS. ON FRIDAY A SURFACE LOW
DEVELOPING IN KANSAS WILL LIFT A WARM FRONT NORTH INTO THE FORECAST
AREA. WITH THE FRONT MOVING THROUGH AND THE ANOTHER UPPER WAVE
MOVING INTO THE AREA THERE IS A BETTER CHANCE FOR THUNDERSTORMS.
SOME OF THESE STORMS COULD BE STRONG TO SEVERE.
SATURDAY AND SATURDAY NIGHT THERE ARE WEAK WAVES THAT MOVES THROUGH
BUT LITTLE IN THE WAY TO GET THINGS STARTED SO ANY PRECIPITATION
WILL BE SPOTTY. THE NEXT CHANCE FOR SOME THUNDERSTORMS WILL BE
SUNDAY INTO SUNDAY NIGHT. ANOTHER STRONGER WAVE MOVES INTO THE AREA
AND A COLD FRONT MOVES THROUGH THE AREA SUNDAY AFTERNOON AND
EVENING. THUNDERSTORMS WILL DEVELOP ALONG THE FRONT AS IT MOVES
THROUGH. SOME OF THESE COULD BE SEVERE.
MONDAY AND MONDAY NIGHT THE UPPER WAVE MOVES TO THE EAST AND A
SURFACE HIGH PRESSURE MOVES INTO THE AREA...KEEPING THINGS DRY.
AGAIN TUESDAY INTO TUESDAY NIGHT THERE ARE A FEW WEAK UPPER LEVEL
WAVES THAT MOVE INTO THE PLAINS. MODELS HAVE SOME FAIRLY SPOTTY
PRECIPITATION AROUND THE AREA WITH THESE UPPER LEVEL WAVES. THE GFS
HAS MORE PRECIPITATION AROUND THAN THE ECMWF DOES.
TEMPERATURES WILL BE SOMEWHAT VARIABLE THROUGH THE WEEK. WITH CLOUDS
AROUND ON FRIDAY THE TEMPERATURES WILL BE A BIT COOLER...WARMING
AFTER THE WARM FRONT LIFTS TO THE NORTH FOR SATURDAY AND SUNDAY THEN
COOLING AGAIN AS THE COOL FRONT MOVE THROUGH MONDAY AND TUESDAY AND
COOLING MORE AFTER THE FRONT MOVES THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION/1105 UPDATE/949 UPDATE...BRYANT
419 UPDATE/SHORT TERM/419 UPDATE...ROSSI
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
322 AM EDT THU MAY 24 2012
.SYNOPSIS...
A SOUTHERLY FLOW OF WARM AIR WILL CONTINUE INTO THE HOLIDAY
WEEKEND BRINGING AFTERNOON TEMPERATURES INTO THE 80S. AN UPPER
LEVEL AREA OF LOW PRESSURE MAY TRIGGER A FEW THUNDERSTORMS THIS
AFTERNOON..ESPECIALLY OVER THE POCONOS AND CATSKILLS. A WEAK FRONT
PASSING THROUGH THE AREA ON FRIDAY MAY TRIGGER MORE WIDESPREAD
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAKNESS IN THE UPR RDG TO THE EAST ALLOWS FOR SOME INCRSD
INSTABILITY OVER THE SRN AND ERN ZONES THIS AFTN. WILL CONT WITH
THE FCST OF A CHANCE OR SLGT CHANCE OF TRWS IN THOSE AREAS. NAM
HAS THE MOST CAPE...WITH BETTER THAN A THSND J/KG AT AVP LATE IN
THE DAY. RUC AND ARW SEEM A BIT MORE RSNBL WITH ARND HALF THAT OF
THE NAM. IN ANY CASE...THUNDER SHD BE ISLTD AND CHANCE OF SVR IS
QUITE SMALL WITH A VERY WEAK WIND FIELD ALOFT. DENSE FOG THIS
MRNG SHD ERODE QUICKLY WITH MIXING. MODELS GUID FOR HIGH TEMPS IN
GOOD AGREEMENT WITH AFTN MAXES FROM THE MID 70S TO LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
YET ANOTHER WEAK BNDRY BANGS INTO THE RDGG SFC AND ALOFT ON FRI.
NAM SHOWS SOME TALL AN SKINNY CAPE...ESP OVER THE NORTH ON FRI
AFTN. LACK OF LL MOISTURE SHD LIMIT CONV DVLPMT BUT WITH THE BNDRY
AND SOME WEAK HGT FALLS ALOFT...CHANCE POPS SEEM RSNBL FOR THE
AFTN...WITH THE BEST CHANCE OVER THE NY COUNTIES.
RDG BOUNCES BACK ON SAT WITH INCRSD HGTS AND WRMG ALOFT. THIS
SERVES TO STABILIZE THE SNDG LIMITING THE PSBLTY OF AFTN TRW. SFC
TEMPS BEGIN TO REBOUND AS WELL WITH TEMPS IN THE 80S ALL STATIONS
AND THE MAV GUID PUSHING AVP INTO THE UPR 80S.
ATTM THERE LOOKS TO BE LTL CHANCE OF SVR...AND WILL BE WELL BLO
AND HEAT ADVISORY THRESHOLD SO WILL REMOVE CAUTIONARY WRDG FROM
THE HWO AND JUST GO WITH A NIL STATEMENT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ON THE LARGE-SCALE...NWP AGREEMENT IS FAIRLY DECENT THAT HEIGHTS
WILL RISE SIGNIFICANTLY OVER THE NERN STATES LATER IN THE WEEKEND
AND EARLY NEXT WEEK...LEADING TO A PD OF ABV NORMAL TEMPS FOR LATE
MAY (HIGHS WELL INTO THE 80S...PSBLY APPCHG 90 DEGS ON SUN AND
MON).
THE MAIN UNCERTAINTIES INVOLVE THE TRACK OF UPR-LVL WAVES ARND THE
PERIPHERY OF THE RIDGE AXIS...AND PSBL CONVECTIVE DEVELOPMENT NEAR A
WARM FRNTL BNDRY...AS IT LIFTS ACRS NY/PA. TO ACCOUNT FOR THIS
SITN...WE`VE CONTINUED TO INDICATE THE POTENTIAL FOR SHRA/TSRA
JUST ABT ANYTIME...FROM SUNDAY INTO MON. CERTAINLY...THIS PD WILL
NOT BE A WASHOUT...AND WILL VERY LIKELY HAVE LONG PDS OF RAIN-FREE
WX. HOWEVER...TIMING OF CONVECTIVE SYSTEMS/PSBL MCV`S THIS FAR OUT
IS NEARLY IMPOSSIBLE...SO WE`LL RETAIN SCHC-CHC POPS.
BY TUE...AS HEIGHTS BEGIN TO FALL ALOFT FROM THE NW...SIGNALLING
THE APPROACH OF A COLD FRNT...WE MAY WELL SEE A BETTER OPPORTUNITY
FOR SHRA/TSRA.
EARLY INDICATIONS ARE THAT DRIER AND COOLER CONDS WILL FOLLOW BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
A MOIST SOUTHEAST FLOW WILL RESULT IN MVFR/IFR RESTRICTIONS
LATER THIS MORNING. AT KRME/KSYR, ONLY MVFR RESTRICTIONS ARE
EXPECTED AND AT KSYR IT MAY BE BRIEF. REST OF TERMINALS WILL SEE
STRATUS AND FOG WITH IFR CONDITIONS BETWEEN 09Z-12Z. CONDITIONS
WILL GRADUALLY IMPROVE TO VFR BY MID TO LATE MORNING WITH VFR
EXPECTED FOR DURATION OF TAF PERIOD. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON BUT NOT MENTIONED IN TAFS DUE TO LIMITED
AREAL COVERAGE. LATE TONIGHT AFTER 06Z MORE IFR/MVFR RESTRICTIONS
ARE POSSIBLE.
LIGHT WINDS BECOMING S/SE AT 7-10 KNOTS THEN LIGHT AGAIN TONIGHT.
.OUTLOOK...
FRIDAY...MVFR POSSIBLE IN SCATTERED MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS.
FRIDAY NIGHT THRU SUN...GENERALLY VFR.
MONDAY...MVFR POSSIBLE IN SCATTERED SHOWERS AND THUNDERSTORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM
SHORT TERM...DGM
LONG TERM...MLJ/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
242 AM EDT THU MAY 24 2012
.SYNOPSIS...
A SOUTHERLY FLOW OF WARM AIR WILL CONTINUE INTO THE HOLIDAY
WEEKEND BRINGING AFTERNOON TEMPERATURES INTO THE 80S. AN UPPER
LEVEL AREA OF LOW PRESSURE MAY TRIGGER A FEW THUNDERSTORMS THIS
AFTERNOON..ESPECIALLY OVER THE POCONOS AND CATSKILLS. A WEAK FRONT
PASSING THROUGH THE AREA ON FRIDAY MAY TRIGGER MORE WIDESPREAD
THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TODAY/...
WEAKNESS IN THE UPR RDG TO THE EAST ALLOWS FOR SOME INCRSD
INSTABILITY OVER THE SRN AND ERN ZONES THIS AFTN. WILL CONT WITH
THE FCST OF A CHANCE OR SLGT CHANCE OF TRWS IN THOSE AREAS. NAM
HAS THE MOST CAPE...WITH BETTER THAN A THSND J/KG AT AVP LATE IN
THE DAY. RUC AND ARW SEEM A BIT MORE RSNBL WITH ARND HALF THAT OF
THE NAM. IN ANY CASE...THUNDER SHD BE ISLTD AND CHANCE OF SVR IS
QUITE SMALL WITH A VERY WEAK WIND FIELD ALOFT. DENSE FOG THIS
MRNG SHD ERODE QUICKLY WITH MIXING. MODELS GUID FOR HIGH TEMPS IN
GOOD AGREEMENT WITH AFTN MAXES FROM THE MID 70S TO LOW 80S.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
YET ANOTHER WEAK BNDRY BANGS INTO THE RDGG SFC AND ALOFT ON FRI.
NAM SHOWS SOME TALL AN SKINNY CAPE...ESP OVER THE NORTH ON FRI
AFTN. LACK OF LL MOISTURE SHD LIMIT CONV DVLPMT BUT WITH THE BNDRY
AND SOME WEAK HGT FALLS ALOFT...CHANCE POPS SEEM RSNBL FOR THE
AFTN...WITH THE BEST CHANCE OVER THE NY COUNTIES.
RDG BOUNCES BACK ON SAT WITH INCRSD HGTS AND WRMG ALOFT. THIS
SERVES TO STABILIZE THE SNDG LIMITING THE PSBLTY OF AFTN TRW. SFC
TEMPS BEGIN TO REBOUND AS WELL WITH TEMPS IN THE 80S ALL STATIONS
AND THE MAV GUID PUSHING AVP INTO THE UPR 80S.
ATTM THERE LOOKS TO BE LTL CHANCE OF SVR...AND WILL BE WELL BLO
AND HEAT ADVISORY THRESHOLD SO WILL REMOVE CAUTIONARY WRDG FROM
THE HWO AND JUST GO WITH A NIL STATEMENT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
3 PM WED UPDATE... ON THE LARGE-SCALE...NWP AGREEMENT IS FAIRLY
DECENT THAT HEIGHTS WILL RISE SIGNIFICANTLY OVER THE NERN STATES
LATER IN THE WEEKEND AND EARLY NEXT WEEK...LEADING TO A PD OF ABV
NORMAL TEMPS FOR LATE MAY (HIGHS WELL INTO THE 80S...PSBLY APPCHG
90 DEGS ON SUN AND MON).
THE MAIN UNCERTAINTIES INVOLVE THE TRACK OF UPR-LVL WAVES ARND THE
PERIPHERY OF THE RIDGE AXIS...AND PSBL CONVECTIVE DEVELOPMENT NEAR A
WARM FRNTL BNDRY...AS IT LIFTS ACRS NY/PA. TO ACCOUNT FOR THIS
SITN...WE`VE CONTINUED TO INDICATE THE POTENTIAL FOR SHRA/TSRA
JUST ABT ANYTIME...FROM LATER SAT NGT RIGHT INTO MON.
CERTAINLY...THIS PD WILL NOT BE A WASHOUT...AND WILL VERY LIKELY
HAVE LONG PDS OF RAIN-FREE WX. HOWEVER...TIMING OF CONVECTIVE
SYSTEMS/PSBL MCV`S THIS FAR OUT IS NEARLY IMPOSSIBLE...SO WE`LL
RETAIN SCHC-CHC POPS.
BY TUE...AS HEIGHTS BEGIN TO FALL ALOFT FROM THE NW...SIGNALLING
THE APPROACH OF A COLD FRNT...WE MAY WELL SEE A BETTER OPPORTUNITY
FOR SHRA/TSRA.
EARLY INDICATIONS ARE THAT DRIER AND COOLER CONDS WILL FOLLOW BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
A MOIST SOUTHEAST FLOW WILL RESULT IN MVFR/IFR RESTRICTIONS
LATER THIS MORNING. AT KRME/KSYR, ONLY MVFR RESTRICTIONS ARE
EXPECTED AND AT KSYR IT MAY BE BRIEF. REST OF TERMINALS WILL SEE
STRATUS AND FOG WITH IFR CONDITIONS BETWEEN 09Z-12Z. CONDITIONS
WILL GRADUALLY IMPROVE TO VFR BY MID TO LATE MORNING WITH VFR
EXPECTED FOR DURATION OF TAF PERIOD. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON BUT NOT MENTIONED IN TAFS DUE TO LIMITED
AREAL COVERAGE. LATE TONIGHT AFTER 06Z MORE IFR/MVFR RESTRICTIONS
ARE POSSIBLE.
LIGHT WINDS BECOMING S/SE AT 7-10 KNOTS THEN LIGHT AGAIN TONIGHT.
.OUTLOOK...
FRIDAY...MVFR POSSIBLE IN SCATTERED MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS.
FRIDAY NIGHT THRU SUN...GENERALLY VFR.
MONDAY...MVFR POSSIBLE IN SCATTERED SHOWERS AND THUNDERSTORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM
SHORT TERM...DGM
LONG TERM...MLJ
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
642 AM CDT THU MAY 24 2012
...UPDATED FOR AVIATION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 408 AM CDT THU MAY 24 2012
THE SHORTER TERM MODELS OF THE NAM AND THE HRRR NOW SHOW THERE WILL
NOT BE ANY PRECIP IN OUR FORECAST AREA TODAY. THE COLD FRONT IS
THROUGH OUR CWA, WITH A LOW PRESSURE SYSTEM POSITIONED OVER
SOUTHEAST COLORADO. AN UPPER LEVEL DISTURBANCE IS MOVING
EAST-NORTHEAST BUT TRAVELING THROUGH AREAS NORTH OF OUR COUNTY
WARNING AREA, NORTHERN KANSAS AND NEBRASKA AND POINTS
NORTHEASTWARD. THERE IS SOME CIRRUS AROUND AND THINK THE GRIDS WILL
PRODUCE MOSTLY SUNNY CONDITIONS. WHEN THE FRONT FIRST WENT THROUGH,
THE WINDS BEHIND THE FRONT QUICKLY PICKED UP INTO ADVISORY LEVELS,
AND THUS A SHORT TERM WIND ADVISORY WAS ISSUED FOR THAT AREA WEST OF
A DIGHTON TO MONTEZUMA LINE, AND ALSO NORTH OF A JOHNSON CITY TO
MONTEZUMA LINE. AT THE TIME OF WRITING THIS SHORT TERM DISCUSSION,
WINDS HAD FALLEN BACK TO LESS THAN ADVISORY CRITERIA AT ALL SITES
EXCEPT HUGOTON AND SCOTT CITY. THIS WIND ADVISORY WILL EXPIRE AT
09Z, AND SHOULD NOT SHOW UP IN THE NEXT ZONE ISSUANCE. TEMPERATURES
TODAY WILL BE COOLER THAN YESTERDAY`S NEAR CENTURY MARKS, DUE TO THE
COLD FRONTAL PASSAGE AND HIGH CLOUDS. HIGHS TODAY SHOULD RANGE FROM
THE MID 80S ALONG THE OKLAHOMA PANHANDLE TO THE UPPER 70S NORTH OF
THE I-70 CORRIDOR.
THE COLD FRONT MENTIONED ABOVE WILL COME BACK NORTH TONIGHT AS A
WARM FRONT. JUST HOW FAST NORTH IT WILL MOVES IS HANDLED
DIFFERENTLY BY THE MODELS. THE NAM MODEL BRINGS THE FRONT NORTH THE
FASTEST, WITH THE GFS AND ECMWF MODELS SLOWER. BY THE TIME THE
FRONT REACHES OUR NORTHERN COUNTIES OF ELLIS, TREGO, RUSH, NESS,
LANE AND SCOTT BY 09Z, THERE COULD BE A FEW THUNDERSTORMS FORM IN
THE ELEVATED UNSTABLE LAYERS OF THE ATMOSPHERE. I ONLY PLACED 20
POPS IN, AS THE TIMING OF THE FRONT IS STILL IN QUESTION. CLOUDS
WILL BLANKET MOST OF SOUTHWESTERN KANSAS THURSDAY NIGHT, AND WINDS
NEAR THE OKLAHOMA BORDER WILL BE SOUTH AT 10 TO 20 MPH BEHIND THE
FRONT AND EASTERLY AT 10 TO 20 MPH NORTH OF THE FRONT. TEMPERATURES
THURSDAY NIGHT
WILL BE SOMEWHAT ELEVATED, ONLY FALLING TO THE MID 60S IN THE
MEDICINE LODGE AND PRATT AREAS, INTO THE LOWER 60S FROM LIBERAL TO
DODGE CITY TO LARNED, AND INTO THE MIDDLE 50S FROM SYRACUSE TO SCOTT
CITY TO WAKEENEY.
.LONG TERM...(FRIDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT THU
MAY 24 2012
A CHALLENGING FORECAST LIES AHEAD FOR THE COMING SEVERAL DAYS, AS A
FEW OPPORTUNITIES FOR CONVECTION APPEAR POSSIBLE. BY FRIDAY MORNING,
A WARM FRONT WILL BE LIFTING NORTHWARD THROUGH SOUTHWEST KANSAS. THE
MODELS DIFFER SIGNIFICANTLY WITH THIS FRONT. THE GFS PRODUCES QPF AS
EARLY AS OVERNIGHT THURSDAY HEADING INTO FRIDAY MORNING, AND REALLY
INCREASING THE QPF AROUND THE 12Z TIMEFRAME. BY CONTRAST THE NAM AND
ECMWF ARE MORE IN LINE WITH A DRY SOLUTION. THE CONVECTION PRODUCED
IN THESE CASES ARE MORE IN LINE WITH THE EDGE OF A CAPPING LATER IN
THE MID LEVELS THAT IS LOCATED ACROSS NORTHERN KANSAS. IN EITHER
CASE; STRONG LOW LEVEL THETA-E ADVECTION AND ISENTROPIC LIFT IN THE
MORNING, OR BREAKING THE CAP LATE IN THE DAY FARTHER NORTH, QUARTER
TO GOLFBALL SIZED HAIL WOULD BE LIKELY. HOWEVER, THE MOST LIKELY
EVENT IS PROBABLY ALONG THE LINES OF THE ECMWF AND NAM GIVEN THE
WARM TEMPERATURES IN THE MID LEVELS OF 13 TO 14 DEGREES C. IF THE
WARM AIR ALOFT IS STRONG ENOUGH OF A CAP ON FRIDAY, THE POTENTIAL
FOR SEVERE CONVECTION MIGHT BE RELEGATED EVEN FARTHER NORTH INTO
NORTH CENTRAL KANSAS AND NEBRASKA. SURFACE TEMPERATURES WILL EXCEED
95 DEGREES IN THIS WARM BOUNDARY LAYER AIR AND LIKELY HIT 100
DEGREES OR MORE IN THE RED HILLS REGION. IT IS UNKNOWN AT THIS TIME
IF THE SMOKE FROM THE NEW MEXICO FIRES WILL PLAY A ROLE IN
INHIBITING INSOLATION WHICH IN TURN COULD PREVENT TEMPERATURES FROM
REACHING THE AFOREMENTIONED VALUES. BUT IT IS SOMETHING TO CONSIDER
IN THE NEXT 24 OR SO HOURS.
HEADING INTO THE WEEKEND, A CONSENSUS OF THE MODELS WOULD SEEM TO
SUPPORT AT LEAST SOME POTENTIAL FOR DRYLINE TRIGGERED CONVECTION
ACROSS CENTRAL KANSAS ON SATURDAY. HOWEVER, IT IS NOT CLEAR AT ALL
JUST WHERE THE DRYLINE MIGHT BE LOCATED AT THIS TIME. GENERALLY
ISOLATED DISCREET CONVECTION WITHIN AMPLE SHEAR FOR AT LEAST THE
POTENTIAL FOR SUPERCELLS PRODUCING UP TO GOLFBALL SIZED HAIL.
A MORE ORGANIZED SEVERE CONVECTIVE POTENTIAL COULD OCCUR ON SUNDAY.
THE FORCING MECHANISMS FOR THIS POTENTIAL WILL BE AN ADVANCING UPPER
TROUGH WITH A LARGE COLD POOL (COOLING TEMPERATURES ALOFT) AND A
LEAD UPPER JET`S RIGHT REAR QUADRANT. THE GFS AND ECMWF BOTH APPEAR
TO SUPPORT A TORNADIC SUPERCELL ENVIRONMENT SUNDAY AFTERNOON ALONG
THE WARM FRONT-SURFACE LOW INTERSECTION.
BEYOND THIS PERIOD, THE FORECAST APPEARS TO CREATE MORE UNCERTAINTY.
THE OVERALL CONSENSUS APPEARS TO BE A FLATTENING OF THE UPPER FLOW
AS THE UPPER JET LIFTS INTO THE UPPER MIDWEST THROUGH TUESDAY. THIS
SHOULD, WITH TIME ALLOW DRIER AIR TO SETTLE OVER WESTERN KANSAS
REDUCING THE ODDS OF THUNDERSTORMS. BEFORE THE ECMWF AND GFS BOTH
TREND RAPIDLY TOWARD STRONG MOISTURE RETURN AND CONVECTION ONCE
AGAIN BY AROUND DAY 7.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM CDT THU MAY 24 2012
A COLD FRONT IS MOVING SOUTHEASTWARD THROUGH SOUTH CENTRAL KANSAS
THIS MORNING. AS OF 11 UTC MSAS ANALYSIS, THE FRONT WAS POSITIONED
FRONT NEAR KMHK TO KP28. THE SURFACE PRESSURE GRADIENT BEHIND THE
FRONT WILL SLOWLY WEAKEN OVER THE AREA AS THE FRONT MOVES INTO
CENTRAL OKLAHOMA. AS A RESULT, NORTHWEST SURFACE WIND WILL DIMINISH
TO UNDER 20 KNOTS AT ALL SITES BY THE LATE MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 83 62 98 70 / 0 10 10 10
GCK 82 60 97 68 / 0 10 10 10
EHA 85 59 93 66 / 0 10 10 10
LBL 85 62 96 68 / 0 10 10 10
HYS 80 59 89 69 / 10 20 20 20
P28 85 67 96 72 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1152 AM EDT THU MAY 24 2012
.UPDATE...
ISSUED AT 1148 AM EDT THU MAY 24 2012
ISSUED A WIND ADVISORY FOR THE REST OF CENTRAL AND ERN CWA AS WINDS
WERE ALREADY GREATER THAN PREVIOUS FORECAST...AND A CORE OF 40-50KT
925MB WINDS WILL MOVE INTO THE CENTRAL AND ERN CWA AROUND 18Z.
EXPECT GUSTS TO AROUND 45KTS TO BE ABLE TO MIX DOWN TO THE SFC THIS
AFTERNOON. STILL WATCHING SEVERE THUNDERSTORM POTENTIAL THIS
AFTERNOON/EVENING OVER MAINLY THE WESTERN HALF OF UPPER MI. WILL BE
EXAMINING POPS/WX MORE CLOSELY FOR UPDATES IN THE NEXT COUPLE OF
HOURS.
&&
.SYNOPSIS...
ISSUED AT 504 AM EDT THU MAY 24 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE UPR
RDG OVER THE NE CONUS/SE CANADA DOWNSTREAM OF DEEP UPR TROF IN THE
ROCKIES. UNDER THE SW FLOW ALF BTWN THESE LARGER SCALE FEATURES...A
SHRTWV/SFC LO LIFTING NEWD NEAR LK WINNIPEG WITH UPR DVGC IN RRQ OF
SUPPORTING 100KT H3 JET MAX HAS CAUSED QUITE A BIT OF SHRA/TS IN MN
MAINLY WITHIN AXIS OF DEEPER MSTR ON THE COLD SIDE OF SFC FNT OVER
WRN LK SUP THAT IS ATTENDANT TO LK WINNIPEG LO. A FEW -SHRA/A LTG
STRIKE OF TWO ARE JUST W OF IWD NEAR THE SFC COLD FNT LOCATION NOT
FAR FM ASHLAND IN NW WI. TO THE E OVER MOST OF THE CWA...BONE DRY
AIRMASS SHOWN ON THE 00Z GRB RAOB /PWAT 0.25 INCH WITH KINX -53/ IS
BRINGING A TRANQUIL OVERNGT WITH JUST SOME SCT HI CLDS. THE APRCH OF
ANOTHER STRONG SHRTWV ROTATING THRU THE WRN TROF IS CAUSING MORE
SHRA/TS TO BREAK OUT IN NEBRASKA UNDER EXPANDING AREA OF COOLING CLD
TOPS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 504 AM EDT THU MAY 24 2012
MAIN FCST CONCERN DURING THIS TIME IS POTENTIAL FOR SVR WX LATE THIS
EVNG ASSOCIATED WITH SHRTWV NOW ROUNDING THE BASE OF THE WRN TROF
AND CAUSING EXPANDING AREA OF SHRA/TS AROUND NEBRASKA.
TDAY...ALTHOUGH SOME OF THE SCT -SHRA NOW ALONG THE COLD FNT WL
DRIFT INTO THE WRN ZNS EARLY THIS MRNG PER SLOWLY VEERING H85 FLOW
TO SW AS SHOWN BY THE 00Z NAM...THE BULK OF THE RA NOW IN MN WL STAY
W AND DIMINISH AS POCKET OF UPR DVGC IN RRQ OF JET MAX IN NW ONTARIO
LIFTS TO THE NE. BUT WITH DRYNESS OF AIRMASS IN PLACE PER THE 00Z
GRB RAOB AND HI AMPLITUDE RDG JUST TO THE E...THESE -SHRA SHOULD
REMAIN OVER THE W AS THE SLOW MOVING COLD FNT STALLS WITH BACKING OF
THE UPR FLOW ASSOCIATED WITH MOTION OF ROCKIES SHRTWV INTO THE
PLAINS. THEN MOST OF THE DAY WILL FEATURE A GUSTY S WIND AS H85 WINDS
INCRS TO 40-45KTS IN ADVANCE OF THE SHRTWV/DVLPG SFC LO IN THE
PLAINS THAT IS FCST TO LIFT NEWD TO NOT FAR FM DLH BY 00Z. CONFINED
CHC POPS TO THE W. DAYTIME HEATING/MIXING WL CAUSE WIND GUSTS TO AT
LEAST APRCH ADVY CRITERIA WITH STEEP LLVL LAPSE RATES AS HI TEMPS
SURGE INTO THE 80S AT SOME PLACES AWAY FM THE MODERATING INFLUENCE
OF MAINLY LK MI. AFT COORDINATION WITH GRB...OPTED TO ISSUE WIND
ADVY FOR MAINLY THE W HALF OF THE CWA AWAY FM THE MORE STABILIZED
KEWEENAW PENINSULA TO ACCOUNT FOR DEEP MIXING...EXCEPTIONAL
INTENSITY OF THE APRCHG DISTURBANCE/SFC LO PRES...AND GFS FCST
H85/H925 S WINDS UP TO 60KTS/50KTS. GFS BUFKIT PROFILES INDICATE
WINDS OF 35-40 KTS WL BE PRESENT IN MIXED LYR AT IWD. ALTHOUGH THE
ARRIVAL OF HIER H95-9 SPECIFIC HUMIDITY IN THIS STRENGTHENING SLY
FLOW WL KEEP MIN RH FM FALLING TO CRITICAL LVLS...THE GUSTY S WINDS
WL STILL BE A CHALLENGE FOR THE PERSONNEL FIGHTING THE SENEY
FIRE/OTHER WILDFIRES. MORE NMRS SHRA/TS ASSOCIATED WITH THE LO
MOVING NEAR DLH MAY ARRIVE OVER THE FAR W IN THE 21Z-24Z TIME.
TNGT...AS THE NEGATIVELY TILTED SHRTWV/SFC LO MOVE QUICKLY NE INTO
ONTARIO...EXPECT A STRONG COLD FROPA ACRS THE CWA. VERY STRONG
DYNAMICS THAT IMPACT MAINLY THE W HALF INCLUDE VIGOROUS DPVA/UPR
DVGC IN THE LEFT EXIT OF SUPPORTING 130KT H3 JET MAX. ALTHOUGH FCST
SDNGS DO NOT SHOW PARTICULARLY STEEP MID LVL LAPSE RATES...INVERTED
V LOOK TO THE T/TD PROFILE IN THE SUB H8-85 LYR FOR IWD AT 00Z WITH
EARLY EVNG FROPA THERE MAXIMIZING LLVL DESTABLIZATION AT PEAK
HEATING TIME SUG THE POTENTIAL FOR DAMAGING WINDS WITH
UNIDIRECTIONAL/SLOWLY VEERING POWERFUL FLOW THAT INCLUDES H7/H85
WINDS AS HI AS 60-70KTS/50-60KTS EVEN THOUGH THERE IS NOT A LOT OF
MID LVL DRY AIR TO MAXIMIZE DCAPE. DESPITE THE STRONG WIND
FIELDS...INVERTED V LLVL T/TD PROFILE AND LACK OF DIRECTIONAL SHEAR
WOULD TEND TO MINIMIZE TORNADO THREAT. SINCE THE MID LVL LAPSE RATES
ARE RELATIVELY WEAK AND LACK OF DRY MID LVL AIR RESULTS IN WBZ HGT
IN THE 12.5-13.0K RANGE...THE LARGE HAIL THREAT DOES NOT APPEAR TOO
HI. SINCE THE SHARPER DYNAMICS WL EXIT TO THE NE AND NOCTURNAL
COOLING WL BEGIN TO HAVE AN IMPACT...EXPECT THE SHRA/TS CHCS AND
SEVERE WX THREAT TO WANE AS THE FRONT MARCHES FARTHER E. VIGOROUS
DRY SLOTTING/ARRIVAL OF LARGER SCALE QVECTOR DVGC IN THE WAKE OF THE
FROPA WL CAUSE DIMINISHING POPS...BUT LINGERING LLVL MSTR MAY STILL
CAUSE A FEW -SHRA IN THE UPSLOPE AREAS OF THE W THRU THE NGT.
GIVEN STRENGTH OF THIS DISTURBANCE...CONCERNED W WINDS IN THE WAKE
OF THE COLD FROPA WL REACH ADVY CRITERIA OVER MAINLY THE EXPOSED
KEWEENAW PENINSULA AFT 06Z WITH W H925 WINDS INCRSG TO 40-50
KTS/VIGOROUS CAD THAT WL MAINTAIN STEEPER LLVL LAPSE RATES DESPITE
SOME STABILIZATION OVER THE RELATIVELY COOL WATERS OF LK SUP/AND
APRCH OF PRES RISE MAX OF 10-15MB/6HRS THAT WL ACCENTUATE
ISALLOBARIC WIND COMPONENT NEARLY IN LINE WITH GRADIENT FLOW.
FRI...WITH THE ARRIVAL OF DRIER AIR AND APRCH OF UPR RDG...EXPECT A
DRY DAY. GUSTY WINDS WL PERSIST WITH DAYTIME HEATING/MIXING EVEN
THOUGH THE PRES GRADIENT IS FCST TO SLOWLY SLACKEN. WITH H85 TEMPS
TOPPING OUT IN THE 8-10C RANGE...MIXING TO H75 ON GFS/NAM FCST SDNGS
YIELD HI TEMPS IN THE 75-80 RANGE WITH DOWNSLOPING FLOW AWAY FM LK
MODERATION IN LLVL WNW FLOW.
.LONG TERM...(AFTER MIDNIGHT FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 621 AM EDT THU MAY 24 2012
EXPECT WINDS TO DIMINISH AND BECOME NEARLY CALM FRIDAY NIGHT...AS
TEMPS FALL INTO THE 40S. WENT WITH THE DRIER NON-NAM SOLUTION FOR
MUCH OF THIS PERIOD...AS THE 24/00Z NAM WAS VERY OPTIMISTIC WITH ITS
PRINTOUT OF PRECIP.
OTHER CHANGES INCLUDED A WARMING OF TEMPS UP A COUPLE OF DEGREES FOR
SATURDAY /COOLEST N NEAR LAKE SUPERIOR/...WITH A GENERALLY SLOWER
ONSET OF PRECIP. THUNDERSTORMS SHOULD STAY ALONG THE WI BORDER
THROUGH THE AFTERNOON HOURS. THESE THUNDERSTORMS WILL PUSH
NORTHWARD...THANKS TO THE WARM FRONT. TEMPS SUNDAY WILL POP BACK
INTO THE 70S WEST SUNDAY. WHILE WE DO HAVE A FCST FOR HIGH CHANCE
POPS THROUGH MUCH OF THE DAY...THE BEST CHANCE WILL MORE THAN LIKELY
BE THROUGH 18Z...BEFORE MUCH OF THE PRECIPITATION MOVES N ACROSS
LAKE SUPERIOR. THUNDERSTORMS WILL END W TO E MONDAY AS THE SFC LOW
PUSHES ACROSS AND EXITS E OF THE AREA. WHILE THERE ARE SILL SOME
SIGNIFICANT DIFFERENCES BETWEEN THE MODELS...THEY ARE IN BETTER
AGREEMENT FOR THIS PERIOD THAN 24 HRS AGO. THE SFC TROUGH WILL
LINGER ACROSS THE CWA THROUGH TUESDAY WITH LOW CHANCE/SLIGHT CHANCE
POPS LINGERING THROUGH THE END OF THE FCST PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 557 AM EDT THU MAY 24 2012
STRONG WINDS AND LLWS REMAIN A CONCERN THROUGH 12Z FRIDAY. SSW WINDS
OF 50-55KTS CONTINUE TO SHOW UP ON THE MARQUETTE 88D RADAR...WHICH
SHOULD ONLY TEMPORARILY DIMINISH ABOUT 5KTS OR SO BEFORE PICKING UP
AGAIN THIS AFTERNOON...WITH 60KTS JUST AHEAD OF THE NEARING COLD
FRONT TO OUR WEST. SHOWERS AND THUNDERSTORMS NEAR IWD AND CMX EARLY
THIS MORNING WILL SLOWLY TRACK TO SAW AROUND OR SHORTLY AFTER 00Z
FRIDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ALONG THE COLD
FRONT DURING THE AFTERNOON AND EVENING WITH CONVECTION...BEFORE
DIMINISHING LATE TONIGHT. STRONG WINDS WILL REMAIN ALOFT...IF NOT AT
THE SURFACE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 621 AM EDT THU MAY 24 2012
ALTHOUGH S WINDS AT SOME OF THE HIGHER PLATFORMS LIKE STANNARD ROCK
WILL PUSH 30-35 KTS INTO TONIGHT IN ADVANCE OF A DEEP LO PRES/STRONG
COLD FRONT MOVING THRU WESTERN LK SUP THIS EVENING...HIGHER OVER
WATER STABILITY WILL LIMIT THE MIXING OF THE STRONGER WINDS TO NEAR
THE SURFACE. ONCE THE FRONT PASSES BY TONIGHT AND THE WIND SHIFTS TO
THE W...EXPECT THE STRONGER WINDS TO MIX CLOSER TO THE SURFACE WITH
THE ARRIVAL OF COOLER AIR. ALTHOUGH THERE IS SOME UNCERTAINTY HOW
MUCH OF THE STRONGER FLOW WILL MAKE IT TO THE SURFACE...OPTED TO
ISSUE GALE WATCH LATE TONIGHT THRU FRI MORNING FOR THE AREA BETWEEN
ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN WILL ENHANCE THE EXPECTED
WSW FLOW. WINDS WILL DIMINISH ON FRI AFTERNOON WITH WEAKENING PRES
GRADIENT.
HIGH PRESSURE ACROSS CENTRAL CANADA FRIDAY NIGHT WILL CROSS ONTARIO
AND LAKE SUPERIOR SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON
SUNDAY. LOW PRESSURE OVER THE NORTHERN PLAINS SUNDAY WILL FILL
ACROSS THE UPPER GREAT LAKES MONDAY INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR MIZ002-
004>007-009>014-084-085.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR LSZ263-
264-266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...TITUS
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...KF
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
621 AM EDT THU MAY 24 2012
.SYNOPSIS...
ISSUED AT 504 AM EDT THU MAY 24 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE UPR
RDG OVER THE NE CONUS/SE CANADA DOWNSTREAM OF DEEP UPR TROF IN THE
ROCKIES. UNDER THE SW FLOW ALF BTWN THESE LARGER SCALE FEATURES...A
SHRTWV/SFC LO LIFTING NEWD NEAR LK WINNIPEG WITH UPR DVGC IN RRQ OF
SUPPORTING 100KT H3 JET MAX HAS CAUSED QUITE A BIT OF SHRA/TS IN MN
MAINLY WITHIN AXIS OF DEEPER MSTR ON THE COLD SIDE OF SFC FNT OVER
WRN LK SUP THAT IS ATTENDANT TO LK WINNIPEG LO. A FEW -SHRA/A LTG
STRIKE OF TWO ARE JUST W OF IWD NEAR THE SFC COLD FNT LOCATION NOT
FAR FM ASHLAND IN NW WI. TO THE E OVER MOST OF THE CWA...BONE DRY
AIRMASS SHOWN ON THE 00Z GRB RAOB /PWAT 0.25 INCH WITH KINX -53/ IS
BRINGING A TRANQUIL OVERNGT WITH JUST SOME SCT HI CLDS. THE APRCH OF
ANOTHER STRONG SHRTWV ROTATING THRU THE WRN TROF IS CAUSING MORE
SHRA/TS TO BREAK OUT IN NEBRASKA UNDER EXPANDING AREA OF COOLING CLD
TOPS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 504 AM EDT THU MAY 24 2012
MAIN FCST CONCERN DURING THIS TIME IS POTENTIAL FOR SVR WX LATE THIS
EVNG ASSOCIATED WITH SHRTWV NOW ROUNDING THE BASE OF THE WRN TROF
AND CAUSING EXPANDING AREA OF SHRA/TS AROUND NEBRASKA.
TDAY...ALTHOUGH SOME OF THE SCT -SHRA NOW ALONG THE COLD FNT WL
DRIFT INTO THE WRN ZNS EARLY THIS MRNG PER SLOWLY VEERING H85 FLOW
TO SW AS SHOWN BY THE 00Z NAM...THE BULK OF THE RA NOW IN MN WL STAY
W AND DIMINISH AS POCKET OF UPR DVGC IN RRQ OF JET MAX IN NW ONTARIO
LIFTS TO THE NE. BUT WITH DRYNESS OF AIRMASS IN PLACE PER THE 00Z
GRB RAOB AND HI AMPLITUDE RDG JUST TO THE E...THESE -SHRA SHOULD
REMAIN OVER THE W AS THE SLOW MOVING COLD FNT STALLS WITH BACKING OF
THE UPR FLOW ASSOCIATED WITH MOTION OF ROCKIES SHRTWV INTO THE
PLAINS. THEN MOST OF THE DAY WILL FEATURE A GUSTY S WIND AS H85 WINDS
INCRS TO 40-45KTS IN ADVANCE OF THE SHRTWV/DVLPG SFC LO IN THE
PLAINS THAT IS FCST TO LIFT NEWD TO NOT FAR FM DLH BY 00Z. CONFINED
CHC POPS TO THE W. DAYTIME HEATING/MIXING WL CAUSE WIND GUSTS TO AT
LEAST APRCH ADVY CRITERIA WITH STEEP LLVL LAPSE RATES AS HI TEMPS
SURGE INTO THE 80S AT SOME PLACES AWAY FM THE MODERATING INFLUENCE
OF MAINLY LK MI. AFT COORDINATION WITH GRB...OPTED TO ISSUE WIND
ADVY FOR MAINLY THE W HALF OF THE CWA AWAY FM THE MORE STABILIZED
KEWEENAW PENINSULA TO ACCOUNT FOR DEEP MIXING...EXCEPTIONAL
INTENSITY OF THE APRCHG DISTURBANCE/SFC LO PRES...AND GFS FCST
H85/H925 S WINDS UP TO 60KTS/50KTS. GFS BUFKIT PROFILES INDICATE
WINDS OF 35-40 KTS WL BE PRESENT IN MIXED LYR AT IWD. ALTHOUGH THE
ARRIVAL OF HIER H95-9 SPECIFIC HUMIDITY IN THIS STRENGTHENING SLY
FLOW WL KEEP MIN RH FM FALLING TO CRITICAL LVLS...THE GUSTY S WINDS
WL STILL BE A CHALLENGE FOR THE PERSONNEL FIGHTING THE SENEY
FIRE/OTHER WILDFIRES. MORE NMRS SHRA/TS ASSOCIATED WITH THE LO
MOVING NEAR DLH MAY ARRIVE OVER THE FAR W IN THE 21Z-24Z TIME.
TNGT...AS THE NEGATIVELY TILTED SHRTWV/SFC LO MOVE QUICKLY NE INTO
ONTARIO...EXPECT A STRONG COLD FROPA ACRS THE CWA. VERY STRONG
DYNAMICS THAT IMPACT MAINLY THE W HALF INCLUDE VIGOROUS DPVA/UPR
DVGC IN THE LEFT EXIT OF SUPPORTING 130KT H3 JET MAX. ALTHOUGH FCST
SDNGS DO NOT SHOW PARTICULARLY STEEP MID LVL LAPSE RATES...INVERTED
V LOOK TO THE T/TD PROFILE IN THE SUB H8-85 LYR FOR IWD AT 00Z WITH
EARLY EVNG FROPA THERE MAXIMIZING LLVL DESTABLIZATION AT PEAK
HEATING TIME SUG THE POTENTIAL FOR DAMAGING WINDS WITH
UNIDIRECTIONAL/SLOWLY VEERING POWERFUL FLOW THAT INCLUDES H7/H85
WINDS AS HI AS 60-70KTS/50-60KTS EVEN THOUGH THERE IS NOT A LOT OF
MID LVL DRY AIR TO MAXIMIZE DCAPE. DESPITE THE STRONG WIND
FIELDS...INVERTED V LLVL T/TD PROFILE AND LACK OF DIRECTIONAL SHEAR
WOULD TEND TO MINIMIZE TORNADO THREAT. SINCE THE MID LVL LAPSE RATES
ARE RELATIVELY WEAK AND LACK OF DRY MID LVL AIR RESULTS IN WBZ HGT
IN THE 12.5-13.0K RANGE...THE LARGE HAIL THREAT DOES NOT APPEAR TOO
HI. SINCE THE SHARPER DYNAMICS WL EXIT TO THE NE AND NOCTURNAL
COOLING WL BEGIN TO HAVE AN IMPACT...EXPECT THE SHRA/TS CHCS AND
SEVERE WX THREAT TO WANE AS THE FRONT MARCHES FARTHER E. VIGOROUS
DRY SLOTTING/ARRIVAL OF LARGER SCALE QVECTOR DVGC IN THE WAKE OF THE
FROPA WL CAUSE DIMINISHING POPS...BUT LINGERING LLVL MSTR MAY STILL
CAUSE A FEW -SHRA IN THE UPSLOPE AREAS OF THE W THRU THE NGT.
GIVEN STRENGTH OF THIS DISTURBANCE...CONCERNED W WINDS IN THE WAKE
OF THE COLD FROPA WL REACH ADVY CRITERIA OVER MAINLY THE EXPOSED
KEWEENAW PENINSULA AFT 06Z WITH W H925 WINDS INCRSG TO 40-50
KTS/VIGOROUS CAD THAT WL MAINTAIN STEEPER LLVL LAPSE RATES DESPITE
SOME STABILIZATION OVER THE RELATIVELY COOL WATERS OF LK SUP/AND
APRCH OF PRES RISE MAX OF 10-15MB/6HRS THAT WL ACCENTUATE
ISALLOBARIC WIND COMPONENT NEARLY IN LINE WITH GRADIENT FLOW.
FRI...WITH THE ARRIVAL OF DRIER AIR AND APRCH OF UPR RDG...EXPECT A
DRY DAY. GUSTY WINDS WL PERSIST WITH DAYTIME HEATING/MIXING EVEN
THOUGH THE PRES GRADIENT IS FCST TO SLOWLY SLACKEN. WITH H85 TEMPS
TOPPING OUT IN THE 8-10C RANGE...MIXING TO H75 ON GFS/NAM FCST SDNGS
YIELD HI TEMPS IN THE 75-80 RANGE WITH DOWNSLOPING FLOW AWAY FM LK
MODERATION IN LLVL WNW FLOW.
.LONG TERM...(AFTER MIDNIGHT FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 621 AM EDT THU MAY 24 2012
EXPECT WINDS TO DIMINISH AND BECOME NEARLY CALM FRIDAY NIGHT...AS
TEMPS FALL INTO THE 40S. WENT WITH THE DRIER NON-NAM SOLUTION FOR
MUCH OF THIS PERIOD...AS THE 24/00Z NAM WAS VERY OPTIMISTIC WITH ITS
PRINTOUT OF PRECIP.
OTHER CHANGES INCLUDED A WARMING OF TEMPS UP A COUPLE OF DEGREES FOR
SATURDAY /COOLEST N NEAR LAKE SUPERIOR/...WITH A GENERALLY SLOWER
ONSET OF PRECIP. THUNDERSTORMS SHOULD STAY ALONG THE WI BORDER
THROUGH THE AFTERNOON HOURS. THESE THUNDERSTORMS WILL PUSH
NORTHWARD...THANKS TO THE WARM FRONT. TEMPS SUNDAY WILL POP BACK
INTO THE 70S WEST SUNDAY. WHILE WE DO HAVE A FCST FOR HIGH CHANCE
POPS THROUGH MUCH OF THE DAY...THE BEST CHANCE WILL MORE THAN LIKELY
BE THROUGH 18Z...BEFORE MUCH OF THE PRECIPITATION MOVES N ACROSS
LAKE SUPERIOR. THUNDERSTORMS WILL END W TO E MONDAY AS THE SFC LOW
PUSHES ACROSS AND EXITS E OF THE AREA. WHILE THERE ARE SILL SOME
SIGNIFICANT DIFFERENCES BETWEEN THE MODELS...THEY ARE IN BETTER
AGREEMENT FOR THIS PERIOD THAN 24 HRS AGO. THE SFC TROUGH WILL
LINGER ACROSS THE CWA THROUGH TUESDAY WITH LOW CHANCE/SLIGHT CHANCE
POPS LINGERING THROUGH THE END OF THE FCST PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 557 AM EDT THU MAY 24 2012
STRONG WINDS AND LLWS REMAIN A CONCERN THROUGH 12Z FRIDAY. SSW WINDS
OF 50-55KTS CONTINUE TO SHOW UP ON THE MARQUETTE 88D RADAR...WHICH
SHOULD ONLY TEMPORARILY DIMINISH ABOUT 5KTS OR SO BEFORE PICKING UP
AGAIN THIS AFTERNOON...WITH 60KTS JUST AHEAD OF THE NEARING COLD
FRONT TO OUR WEST. SHOWERS AND THUNDERSTORMS NEAR IWD AND CMX EARLY
THIS MORNING WILL SLOWLY TRACK TO SAW AROUND OR SHORTLY AFTER 00Z
FRIDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ALONG THE COLD
FRONT DURING THE AFTERNOON AND EVENING WITH CONVECTION...BEFORE
DIMINISHING LATE TONIGHT. STRONG WINDS WILL REMAIN ALOFT...IF NOT AT
THE SURFACE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 621 AM EDT THU MAY 24 2012
ALTHOUGH S WINDS AT SOME OF THE HIGHER PLATFORMS LIKE STANNARD ROCK
WILL PUSH 30-35 KTS INTO TONIGHT IN ADVANCE OF A DEEP LO PRES/STRONG
COLD FRONT MOVING THRU WESTERN LK SUP THIS EVENING...HIGHER OVER
WATER STABILITY WILL LIMIT THE MIXING OF THE STRONGER WINDS TO NEAR
THE SURFACE. ONCE THE FRONT PASSES BY TONIGHT AND THE WIND SHIFTS TO
THE W...EXPECT THE STRONGER WINDS TO MIX CLOSER TO THE SURFACE WITH
THE ARRIVAL OF COOLER AIR. ALTHOUGH THERE IS SOME UNCERTAINTY HOW
MUCH OF THE STRONGER FLOW WILL MAKE IT TO THE SURFACE...OPTED TO
ISSUE GALE WATCH LATE TONIGHT THRU FRI MORNING FOR THE AREA BETWEEN
ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN WILL ENHANCE THE EXPECTED
WSW FLOW. WINDS WILL DIMINISH ON FRI AFTERNOON WITH WEAKENING PRES
GRADIENT.
HIGH PRESSURE ACROSS CENTRAL CANADA FRIDAY NIGHT WILL CROSS ONTARIO
AND LAKE SUPERIOR SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON
SUNDAY. LOW PRESSURE OVER THE NORTHERN PLAINS SUNDAY WILL FILL
ACROSS THE UPPER GREAT LAKES MONDAY INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY FROM 1 PM EDT /NOON CDT/ THIS AFTERNOON TO 8 PM
EDT /7 PM CDT/ THIS EVENING FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR LSZ263-
264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...KF
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
646 AM CDT THU MAY 24 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
/412 AM CDT THU MAY 24 2012/
Short Range (Today through Saturday)...
Several questions have cropped up over the past 12-24 hours which
has introduced some uncertainty with respect to temperatures and
rain chances today and rain chances on Friday.
The overall synoptic pattern features a broad upper trough from the
Northern/Central Rockies into the Upper MS Valley and an associated
cold front stretching from eastern MN through the OK/TX Panhandles.
An embedded shortwave will lift northeast out of CO today resulting
in a deepening surface low tracking northeast along the front from
KS into western IA. The models have been consistent in tracking the
cold front through the CWA today and then stalling just south of the
forecast area tonight before lifting back north as a warm front on
Friday.
Any convection today will be along and west of the cold front
as inspection of progged soundings east of the front depict an
impressive elevated mixed layer(EML) which will act as a brick wall
and prevent any convection forming within the warm sector. In
addition the models have been generating a large area of clouds
around 6k ft across KS during the pre-dawn hours which is expected
to expand east across the forecast area this morning. This cloud
cover will likely suppress surface heating across eastern
KS/western MO today. Initially one could argue highs not making it
out of the 70s. However, by mid/late afternoon the back edge of
these clouds will probably scatter out and allow temperatures to
rebound, possibly into the lower 80s. The eastern CWA should still
be able to heat up into the mid/upper 80s before these clouds reach
them. Short term convective models and conceptual models suggest
convection will have a tough time developing today despite favorable
vertical shear profiles. Marginal instability, a shortwave passing
north of the region and minimal low level convergence should only
support isolated convection. The severe threat will also be muted
with north central and northeast MO having the best chance.
First part of tonight will likely be dry as high pressure briefly
settles in drawing cooler/drier air across most of the CWA. Have had
to lower overnight temperatures due to degree of cool air behind the
front. Building heights aloft on Friday will force the front north.
How strong the isentropic ascent is north of the warm front will
likely determine how much convection forms. NAM/GFS/ECMWF have been
advertising varying amounts of qpf north of the warm front for the
past several runs and hard to argue against it occurring. There are
some signs that a vorticity lobe at h7 will develop across KS early
Friday morning and provide additional support to generate scattered
convection mainly north of the MO River. Some concern for severe
potential across northwest MO/northeast KS during the afternoon.
Location of the warm front during the afternoon will be key as
there will be more than enough instability and shear to support
severe storms. Considerable cloud cover north of the warm front will
keep temperatures from warming. Temperatures will be able to heat up
well into the 80s as the warm front lifts north.
The hot and increasingly humid air will finally arrive on Saturday
as mid/upper level heights build into the region. The EML will
strengthen and keep us dry. Will be flirting with record high
temperatures.
MJ
Medium Range (Sunday through Wednesday)...
Temperatures will remain well above average on Sunday, though a
slight decrease in 850 hPa temps will allow surface temps to be a
couple of degrees cooler than Saturday. Deep upper ridge over the
Southeast will break down on Monday as a closed upper low moves into
the far Upper Midwest. This will allow a weak surface front to drop
into the region Monday afternoon and evening with scattered showers
and thunderstorms remaining a good bet with frontal passage through
late Monday night.
Upper pattern will transition to quasi-zonal by Tuesday and
Wednesday as the front lingers just south of the forecast area.
Elevated baroclinic region will set up a bit further north which
could favor additional showers or thunderstorms depending on timing
of weak upper impulses. Better chances for this right now appear to
be on Wednesday, especially if the GFS is correct with its deeper
surface ridge over the Plains on Tuesday.
Hawblitzel
&&
.CLIMATE...
With the potential for near record temperatures over the holiday
weekend, here are the normals and records through Memorial Day:
Kansas City:
Avg High/Low Record High Records Max Low
Saturday 5/26........78/57...........92 in 1985........68 in 1987
Sunday 5/27..........78/58...........94 in 2006........70 in 2006
Monday 5/28..........78/58...........93 in 2006........75 in 2006
St. Joseph
Saturday 5/26.........79/57..........94 in 1967, 1926...64 in 2008
Sunday 5/27...........79/58..........93 in 2006, 1966...69 in 1991
Monday 5/28...........80/58..........94 in 1998.........75 in 2006
&&
.AVIATION...
For the 12z TAFs, marginal low level wind shear conditions will
continue through at least mid morning before the low level jet mixes
out and/or weakens. Gusty southerly winds will veer to the southwest
as a weakening cold front approaches from the west. While VFR
conditions will continue, a large area of cigs around 4k ft agl will
overspread the terminals at the start of the forecast period. Prefer
latest RUC which is closer to the current cigs moving across KS. A
very warm layer just above these clouds will act as a block on any
convective development. Could see a few sprinkles but no measurable
rain is expected.
MJ
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1009 AM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1010 AM EDT THURSDAY...FCST IN GREAT SHAPE THIS MORNING WITH
ONLY MINOR CHANGES NEEDED. VIS SATL PIC SHOWS LOW CLOUDS SLOWLY
DISSIPATING ACRS EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT
AS SFC HEATING CONTS THESE CLOUDS WL DEVELOP INTO A
SCATTERED/BROKEN CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV
4KM SHOWS SOME INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM
INTO THE U70S TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI
VALUES NEAR -3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF
SUBSIDENCE AND ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER
LVL RIDGE ACRS OUR REGION. THIS WL LIMIT AREAL COVERAGE OF
CONVECTION THIS AFTN...THINKING JUST A SCHC DACKS/SLV AND
CENTRAL/EASTERN VT ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST
OF CWA WL BE RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO
L80S CPV TO M/U 70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 521 AM EDT THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER
THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT...WITH FAIR AND DRY
WEATHER EXPECTED. A FRONTAL SYSTEM JUST SOUTH OF THE REGION SUNDAY
NIGHT WILL BEGIN TO MOVE SLOWLY NORTHEAST AS A WARM FRONT ON
MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
REGION MONDAY AFTERNOON AND CONTINUING INTO MONDAY NIGHT AND
TUESDAY. A COLD FRONT WILL THEN MOVE THROUGH THE REGION TUESDAY
NIGHT WITH A CHANCE FOR SOME MORE SHOWERS AND THUNDERSTORMS.
EXPECTING COOLER TEMPERATURES ALONG WITH CLOUD COVER LINGERING
ACROSS THE REGION ON WEDNESDAY...SO HAVE KEPT IN SLIGHT CHANCE
POPS FOR SHOWERS ON WEDNESDAY. TEMPERATURE FORECAST FOR MONDAY AND
TUESDAY COULD BE A BIT TRICKY AND WILL DEPEND ON WHERE THIS SLOW
MOVING WARM FRONT WILL BE ACROSS THE REGION ON THESE DAYS. HAVE
LEANED TOWARD ENSEMBLE MOS MEANS FOR MAX AND MIN TEMPERATURES ON
MONDAY AND TUESDAY.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
THROUGH 12Z FRIDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE
PERIOD...EXCEPT FOR SOME AREAS OF MVFR/IFR IN FOG AND MIST EARLY
THIS MORNING. EXPECTING AND FOG OR MIST WILL BURN OFF BY 14Z
THURSDAY. VISIBLE SATELLITE LOOP SHOWING LOW STRATUS CLOUDS ACROSS
EASTERN VERMONT AS OF 1130Z THURSDAY. THESE LOWER CEILINGS MAY NOT
LIFT UNTIL 16-17Z THURSDAY. GUIDANCE SHOWING SOME STEEP LOW LEVEL
LAPSE RATES TO DEVELOP ACROSS THE REGION TODAY...SO THERE COULD BE
SOME ISOLATED SHOWERS AND A POSSIBLE THUNDERSTORMS THIS AFTERNOON.
HAVE NOT INCLUDED ANY MENTION IN THE TAFS AT THIS TIME...DUE TO
LOCALIZED NATURE OF THIS. SURFACE PRESSURE GRADIENT TO TIGHTEN
ACROSS THE REGION TODAY...WITH SURFACE WINDGUSTS OF AROUND 20
KNOTS OR GREATER POSSIBLE BETWEEN 14Z-17Z THURSDAY AND CONTINUING
UNTIL 00Z FRIDAY. EXPECTING SURFACE WINDS TO DIMINISH TO LESS THAN
10 KNOTS AFTER 00Z FRIDAY. EXPECTING SOME MORE AREAS OF IFR/MVFR
CEILINGS IN FOG AND MIST...MAINLY AFTER 04Z FRIDAY...ESPECIALLY
ACROSS EASTERN VERMONT.
OUTLOOK 06Z FRIDAY THROUGH MONDAY...
06Z FRIDAY THROUGH 18Z FRIDAY...GENERALLY VFR UNDER RIDGE OF HIGH
PRESSURE...WITH MORNING FOG/BR POSSIBLE. 18Z FRIDAY THROUGH
18Z MONDAY...GENERALLY VFR. 18Z MONDAY THROUGH 00Z TUESDAY CHANCES
FOR MVFR IN SCATTERED SHOWERS/TSTORMS AS A WARM FRONT LIFTS SLOWLY
NORTHEAST ACROSS THE REGION.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...WGH
AVIATION...WGH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
652 AM EDT THU MAY 24 2012
.SYNOPSIS...
A SOUTHERLY FLOW OF WARM AIR WILL CONTINUE INTO THE HOLIDAY
WEEKEND BRINGING AFTERNOON TEMPERATURES INTO THE 80S. AN UPPER
LEVEL AREA OF LOW PRESSURE MAY TRIGGER A FEW THUNDERSTORMS THIS
AFTERNOON..ESPECIALLY OVER THE POCONOS AND CATSKILLS. A WEAK FRONT
PASSING THROUGH THE AREA ON FRIDAY MAY TRIGGER MORE WIDESPREAD
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAKNESS IN THE UPR RDG TO THE EAST ALLOWS FOR SOME INCRSD
INSTABILITY OVER THE SRN AND ERN ZONES THIS AFTN. WILL CONT WITH
THE FCST OF A CHANCE OR SLGT CHANCE OF TRWS IN THOSE AREAS. NAM
HAS THE MOST CAPE...WITH BETTER THAN A THSND J/KG AT AVP LATE IN
THE DAY. RUC AND ARW SEEM A BIT MORE RSNBL WITH ARND HALF THAT OF
THE NAM. IN ANY CASE...THUNDER SHD BE ISLTD AND CHANCE OF SVR IS
QUITE SMALL WITH A VERY WEAK WIND FIELD ALOFT. DENSE FOG THIS
MRNG SHD ERODE QUICKLY WITH MIXING. MODELS GUID FOR HIGH TEMPS IN
GOOD AGREEMENT WITH AFTN MAXES FROM THE MID 70S TO LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
YET ANOTHER WEAK BNDRY BANGS INTO THE RDGG SFC AND ALOFT ON FRI.
NAM SHOWS SOME TALL AN SKINNY CAPE...ESP OVER THE NORTH ON FRI
AFTN. LACK OF LL MOISTURE SHD LIMIT CONV DVLPMT BUT WITH THE BNDRY
AND SOME WEAK HGT FALLS ALOFT...CHANCE POPS SEEM RSNBL FOR THE
AFTN...WITH THE BEST CHANCE OVER THE NY COUNTIES.
RDG BOUNCES BACK ON SAT WITH INCRSD HGTS AND WRMG ALOFT. THIS
SERVES TO STABILIZE THE SNDG LIMITING THE PSBLTY OF AFTN TRW. SFC
TEMPS BEGIN TO REBOUND AS WELL WITH TEMPS IN THE 80S ALL STATIONS
AND THE MAV GUID PUSHING AVP INTO THE UPR 80S.
ATTM THERE LOOKS TO BE LTL CHANCE OF SVR...AND WILL BE WELL BLO
AND HEAT ADVISORY THRESHOLD SO WILL REMOVE CAUTIONARY WRDG FROM
THE HWO AND JUST GO WITH A NIL STATEMENT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ON THE LARGE-SCALE...NWP AGREEMENT IS FAIRLY DECENT THAT HEIGHTS
WILL RISE SIGNIFICANTLY OVER THE NERN STATES LATER IN THE WEEKEND
AND EARLY NEXT WEEK...LEADING TO A PD OF ABV NORMAL TEMPS FOR LATE
MAY (HIGHS WELL INTO THE 80S...PSBLY APPCHG 90 DEGS ON SUN AND
MON).
THE MAIN UNCERTAINTIES INVOLVE THE TRACK OF UPR-LVL WAVES ARND THE
PERIPHERY OF THE RIDGE AXIS...AND PSBL CONVECTIVE DEVELOPMENT NEAR A
WARM FRNTL BNDRY...AS IT LIFTS ACRS NY/PA. TO ACCOUNT FOR THIS
SITN...WE`VE CONTINUED TO INDICATE THE POTENTIAL FOR SHRA/TSRA
JUST ABT ANYTIME...FROM SUNDAY INTO MON. CERTAINLY...THIS PD WILL
NOT BE A WASHOUT...AND WILL VERY LIKELY HAVE LONG PDS OF RAIN-FREE
WX. HOWEVER...TIMING OF CONVECTIVE SYSTEMS/PSBL MCV`S THIS FAR OUT
IS NEARLY IMPOSSIBLE...SO WE`LL RETAIN SCHC-CHC POPS.
BY TUE...AS HEIGHTS BEGIN TO FALL ALOFT FROM THE NW...SIGNALLING
THE APPROACH OF A COLD FRNT...WE MAY WELL SEE A BETTER OPPORTUNITY
FOR SHRA/TSRA.
EARLY INDICATIONS ARE THAT DRIER AND COOLER CONDS WILL FOLLOW BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
CONDITIONS HAVE IMPROVED RAPIDLY EARLY THIS MORNING WITH ONLY
LINGERING MVFR CONDITIONS POSSIBLE THROUGH 14Z. REMAINDER OF TODAY
WILL FEATURE VFR CONDITIONS WITH SCT/BKN CLOUDS AT 4K FT. ISOLATED
CONVECTION IS POSSIBLE THIS AFTERNOON BUT NOT MENTIONED IN TAFS
DUE TO LIMITED AREAL COVERAGE. MOIST SOUTHEAST FLOW WILL BRING
MORE RESTRICTIONS LATE TONIGHT ESPECIALLY ACROSS NE PA AND
SOUTHERN TIER OF NEW YORK. FOR NOW WENT MVFR AFTER 06Z.
S/SE AT 7-10 KNOTS.
.OUTLOOK...
FRIDAY...MVFR POSSIBLE IN SCATTERED MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS.
FRIDAY NIGHT THRU SUN...GENERALLY VFR.
MONDAY...MVFR POSSIBLE IN SCATTERED SHOWERS AND THUNDERSTORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM
SHORT TERM...DGM
LONG TERM...MLJ/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1000 AM EDT THU MAY 24 2012
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN OVER THE EAST COAST INTO THE
WEEKEND AS A WEAKENING COLD FRONT APPROACHES FROM THE WEST AND
BECOMES STATIONARY ACROSS LAKE ERIE FRIDAY EVENING. THE FRONT WILL
LINGER NEAR THE SOUTH SHORE OF LAKE ERIE SATURDAY AND DRIFT NORTH
AS A WARM FRONT SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
12Z SOUNDINGS SUPPORT THE CURRENT FORECAST WITH MINOR CHANGES. THE
STRONGER PRESSURE GRADIENT WITH SOUTHERLY FLOW WILL LIMIT THE LAKE
BREEZE TO THE IMMEDIATE LAKESHORE. WILL LOWER MAX TEMPERATURE AT
ERI A TAD. THE HRRR SHOWS WIDELY SCATTERED CONVECTION OVER NW PA
AND THE EASTERN COUNTIES SO WILL KEEP THE 20 PERCENT POP GOING.
WATER VAPOR SHOWS SMALL VORTICITES OVER THE WESTERN CAROLINAS AND
DELMARVA ALL MOVING NORTHEAST. THESE FEATURES SHOULD NOT AFFECT
THE AREA SO FORECING FOR CONVECTION IS DIFFICULT TO DISCERN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
UNCERTAINTY CONTINUES WITH THE FORECAST FOR THE HOLIDAY WEEKEND. A
WEAKENING COLD FRONT WILL MOVE ACROSS THE REGION ON FRIDAY WHICH
WILL BRING THE CHANCE OF THUNDERSTORMS...MAINLY ACROSS THE EASTERN
THIRD OF THE COUNTY WARNING AREA. WE WILL HAVE TO MONITOR THE
STRENGTH OF STORMS THAT DEVELOP AHEAD OF THE FRONT ACROSS NW PA
FRIDAY AFTERNOON/EVENING. BY FRIDAY NIGHT THE FRONTAL BOUNDARY
WILL STALL OVER CENTRAL OHIO. THIS BOUNDARY WILL THEN LIFT BACK TO
THE NORTH BY SATURDAY AFTERNOON. THIS IS WHEN THE UNCERTAINTY ARRIVES
IN THE FORECAST. MODELS ARE DIFFERING ON HOW FAST TO MOVE THE WARM
FRONT NORTH. THIS COULD END UP HAVING SIGNIFICANT IMPACTS ON
WHERE THUNDERSTORMS OCCUR AND HOW WARM THE REGION CAN GET SATURDAY
INTO SUNDAY. FOR NOW WE HAVE LEANED TOWARD THE ECMWF SOLUTION THAT
LIFTS THE BOUNDARY NORTHWARD SLIGHTLY FASTER AND KEEPS THE CHANCES
OF THUNDERSTORMS NORTH OF A KTOL TO MEADVILLE LINE SATURDAY NIGHT
AND THEN NORTH OF THE LAKE ON SUNDAY.
SINCE WE HAVE LEANED TOWARD THE ECMWF TRENDS WE EXPECT TO SEE
HIGHS NEAR TO SLIGHTLY WARMER THAN THE CURRENT GUIDANCE. HIGHER
DEWPOINTS WILL MAKE IT FEEL EVEN WARMER WITH HEAT INDEX VALUES
INTO THE LOWER AND MIDDLE 90S ON SUNDAY.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
MODELS CONTINUE TO LOOK VERY WARM TO HOT ON MON. AN APPROACHING COLD
FRONT COULD TRIGGER AN ISOLATED TSRA FOR MAINLY THE NW HALF. TIMING
OF COLD FRONT LATE MON NIGHT INTO TUE SO WILL KEEP PLAN TO SPREAD
CHANCE POPS SE THESE PERIODS...SHIFTING SMALL CHANCE INTO MAINLY THE
SE FOR TUE NIGHT. TEMPS COOL SOME FOR TUE AND MORE SO FOR WED AS NW
FLOW CONTINUES TO BRING COOLER AIR INTO THE AREA FROM CANADA.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
ANY PATCHY DAYBREAK FOG WILL DISSIPATE BY 13Z. WILL SEE SCT TO
LOCALLY BKN CU DEVELOP DURING MIDDAY HOURS THEN DISSIPATE TOWARD
SUNSET. AN ISOLATED SHRA OR TSRA COULD DEVELOP IN THE AFTERNOON OVER
THE EAST BUT NOT ENOUGH COVERAGE TO MENTION IN TAF. CAK AND YNG
WOULD BE MOST LIKELY SITES TO BE AFFECTED BY ANY ISOLATED CONVECTION
THAT WOULD DEVELOP. SOUTH TO SE FLOW SETS UP TODAY AND COULD GUST
AROUND 20 KNOTS THIS AFTERNOON AND TONIGHT NEAR THE LAKESHORE.
.OUTLOOK...NON-VFR POSSIBLE IN ISOLD TO SCT TSRA FRI THRU MON AND
PATCHY DAYBREAK BR AND HZ.
&&
.MARINE...
LIGHT SE FLOW WILL INCREASE SOME TODAY AND A LITTLE MORE TONIGHT
AHEAD OF A WEAKENING COLD FRONT THAT WILL CROSS THE LAKE FRI
MORNING. WARM TEMPS OVER THE COOLER LAKE SHOULD KEEP WIND SPEEDS 15
KNOTS OR LESS MOST OF THE TIME. FLOW BECOMES WSW AFTER FROPA FRI
AFTERNOON BUT SHOULD QUICKLY DIMINISH INTO THE EVENING AS HIGH
PRESSURE MOVES OVER THE LAKE.
THE FLOW SHOULD VEER AROUND TO NE FOR SAT. FORECAST FOR LATER SAT
NIGHT AND SUN MORE UNCERTAIN AS MODELS DIFFER ON HOW QUICKLY A
WARM FRONT WILL LIFT NORTH THROUGH THE LAKE. THINK BY SUN NIGHT
THE FRONT SHOULD HAVE MOVED NORTH OF THE LAKE AND WINDS SHOULD BE
MAINLY SSW...AND CONTINUE ON MON.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...REL
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
258 PM MDT THU MAY 24 2012
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 256 PM MDT THU MAY 24 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
EXTENDING FROM THE PACIFIC NORTHWEST ACROSS T HE NORTHERN
PLAINS...WITH WEST/SOUTHWEST FLOW OVER THE CENTRAL ROCKIES AND
CENTRAL HIGH PLAINS. A SERIES OF SHORTWAVE TROUGHS ARE CURRENTLY
TRACKING WITHIN THE MEAN FLOW WITH SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH THESE FEATURES OVER NORTHERN COLORADO AND NORTH
CENTRAL NEBRASKA. A STATIONARY FRONT EXTENDS FROM EASTERN KANSAS
SOUTH INTO NORTHCENTRAL TEXAS...AND THEN NORTH INTO SOUTH-CENTRAL
COLORADO.
TONIGHT...A CLOSED LOW CENTER WITHING THE LARGE SCALE TROUGH WILL
MOVE EAST/NORTHEAST INTO THE NORTHERN PLAINS WITH LARGE SCALE
ASCENT SPREADING SOUTH AND EAST TOWARDS SOUTHWEST NEBRASKA. THE
STATIONARY FRONT TO THE SOUTH WILL BEGIN TO MOVE NORTH IN RESPONSE
TO STRENGTHENING LEE TROUGH OVER EASTERN COLORADO. A STRONG LLJ IS
ADVERTISED TO DEVELOP BY 06Z TONIGHT WHICH COULD ALSO ACT AS A
FOCUS FOR SHOWER THUNDERSTORM DEVELOPMENT OVER OUR CWA. VERY
STRONG SHEAR WILL DEVELOP OVERNIGHT ALONG WITH ELEVATED
INSTABILITY NEAR THE NOSE OF THE LLJ. BEST FORCING LOOKS TO BE
EITHER NORTH OR SOUTH OF THE CWA. IM ALSO NOT SURE ABOUT HOW MUCH
TD WILL RECOVER NORTH OF THE FRONT. I KEPT POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORY...WITH BEST COVERAGE LATE TONIGHT WHEN LLJ
IS EXPECTED TO DEVELOP. THERE CONTINUES TO BE INDICATION OF FOG
DEVELOPMENT WITH EASTERLY FLOW AROUND SUNRISE TOMORROW...SO I KEPT
PATCHY FOG MENTION.
FRIDAY..SHOWER/THUNDERSTOM ACTIVITY SHOULD COME TO AN END FROM
THE SOUTHWEST TO THE NORTHEAST THROUGH THE DAY...WITH ACTIVITY
POSSIBLY LINGERING OVER NORTHERN PARTS OF THE FORECAST AREA INTO
FRIDAY EVENING. THERE IS A LARGE SPREAD IN GUIDANCE ON TIMING OF
WARM FRONT FRIDAY WITH NAM THE SLOW OUTLIER. NAM SOLUTION WOULD
KEEP STRATUS/FOG IN PLACE ALONG WITH MUCH COOLER AIRMASS.
GFS/ECMWF FAVOR THE CLEARING SOLUTION ALONG WITH MUCH WARMER
TEMPERATURES ACROSS THE SOUTHWEST..WHICH IS WHERE I LEANED THIS
FORECAST CYCLE.
FRIDAY NIGHT...PRIMARY ADJUSTMENT TO THIS PERIOD WAS TO BUMP
OVERNIGHT LOWS UP A NOTCH OR TWO WITH SOUTHERLY/SOUTHEASTERLY FLOW
IN PLACE ACROSS THE FORECAST AREA. WILL SEE SLIGHT CHANCE/CHANCE
POPS OVER THE FAR NORTHEAST PORTION OF THE FORECAST AREAS DURING
THE OVERNIGHT HOURS BEFORE SHIFTING OUT OF THE AREA BY AROUND
SUNRISE ON SATURDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 256 PM MDT THU MAY 24 2012
ACTIVE WEATHER PATTERN SETTING UP FOR THE EXTENDED WITH A FEW
PERIODS OF STRONG TO SEVERE CONVECTION APPEARING POSSIBLE.
SATURDAY AND SATURDAY NIGHT...WARM FRONT LIFTS NORTH INTO NEBRASKA
DURING THE DAY WITH A DRYLINE SETTING UP. H85 TEMPS WARM TO AROUND
30C OVER EASTERN COLORADO WITH MID TO UPPER 20S C ELSEWHERE.
RESULT WILL BE AFTERNOON TEMPS APPROACHING THE CENTURY MARK IN A
FEW LOCATIONS. EVERYONE SHOULD SEE AT LEAST THE LOW/MID 90S.
SATURDAY LOOKS TO BE A VERY WINDY DAY ACROSS AT LEAST THE WESTERN
TWO-THIRDS OF THE FORECAST AREA WITH LATEST GUIDANCE HINTING AT
THE POTENTIAL FOR BORDERLINE HIGH WIND WARNING GUSTS. CONSIDERED
HOISTING A HIGH WIND WATCH FOR WESTERN HALF BUT OPTED TO HOLD OFF
AND ALLOW OVERNIGHT SHIFT TO HAVE ANOTHER RUN OF NWP GUIDANCE. AT
THE LEAST...APPEARS AS THOUGH A WIND ADVISORY WILL BE NEEDED FOR
MUCH OF THE AREA. DEW POINTS WILL TANK ACROSS THE WEST WHICH WILL
RESULT IN RH VALUES FALLING TO AROUND 10 PERCENT. FUELS PAGE
INDICATES SUFFICIENT GREEN-UP IS ONGOING WHICH MAY LIMIT FIRE
WEATHER POTENTIAL BUT THIS IS ALSO SOMETHING THAT WILL NEED TO
BE MONITORED OVER THE NEXT FEW FORECAST SHIFTS. DISCREPANCIES DO
EXIST IN THE PLACEMENT OF THE DRYLINE BUT A SLIGHT CHANCE FOR
CONVECTION OVER THE EASTERN HALF OF THE FORECAST AREA APPEARS
JUSTIFIED. GIVEN INVERTED-V NATURE OF VERTICAL SOUNDING
PROFILES...ANY STORM WHICH DEVELOPS WILL HAVE THE POTENTIAL TO
PRODUCE STRONG WIND GUSTS. LARGE HAIL WILL ALSO BE POSSIBLE THOUGH
SHEAR PROFILES DON`T BECOME STRONGLY FAVORABLE UNTIL AFTER 00Z.
SUNDAY AND SUNDAY NIGHT...POTENT MID/UPPER TROUGH WILL BEGIN TO
TRANSLATE ACROSS THE GREAT BASIN/ROCKIES ON SUNDAY WITH INCREASING
FORCING FOR ASCENT AS THE DAY PROGRESSES. PRIMARY QUESTION WILL BE
THE ULTIMATE LOCATION OF THE DRYLINE. EAST OF THE DRYLINE...DEW
POINT WILL SURGE INTO THE UPPER 50S AND PERHAPS EVEN THE LOWER
60S. DEEP LAYER SHEAR OF 40 TO 50 KTS WILL AID IN UPDRAFT
ORGANIZATION WHILE STRONG LOW LEVEL PARAMETERS WOULD ALSO SUPPORT
A TORNADO THREAT. GREATEST THREAT IS CURRENTLY INDICATED TO BE
GENERALLY ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. INTERESTED
PARTIES WILL WANT TO CLOSELY MONITOR THE LATEST FORECAST
INFORMATION.
MONDAY THROUGH TUESDAY...PRIMARY MID/UPPER LOW SHIFTS EASTWARD
ACROSS THE SOUTHERN PRAIRIE PROVINCES OF CANADA MONDAY INTO
TUESDAY MORNING WITH WEAK RIDGING/QUASI-ZONAL FLOW ACROSS THE
CENTRAL HIGH PLAINS. RESULT SHOULD BE SEASONABLE TEMPS WITH DRY
CONDITIONS EXPECTED UNTIL AT LEAST TUESDAY AFTERNOON WHEN A
SHORTWAVE TROUGH MOVES ACROSS THE AREA.
WEDNESDAY THROUGH THURSDAY...MID/UPPER RIDGING BUILDS ACROSS THE WESTERN
CONUS WITH A NEGATIVELY TILTED SHORTWAVE TROUGH AND AN ASSOCIATED
SURFACE COLD FRONT DROPPING SOUTHEAST ACROSS THE DAKOTA AND
NEBRASKA. BROAD SCALE FORCING FOR ASCENT INCREASES BY WEDNESDAY
AFTERNOON WHICH WILL AID IN THE DEVELOPMENT OF CONVECTION OVER
PRIMARILY SOUTHWEST NEBRASKA AND NORTHWEST KANSAS. WILL CARRY
PRIMARILY CHANCE POPS DURING THIS TIME PERIOD WITH MUCH COOLER AIR
FILTERING INTO THE REGION BEHIND THE FRONT ON THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1145 AM MDT THU MAY 24 2012
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT BOTH KGLD AND KMCK
TERMINALS THROUGH LATE TONIGHT. SHOWERS AND THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE AREA TONIGHT. BASED ON EXPECTED SCATTERED
COVERAGE I INCLUDED VCTS AT BOTH TERMINALS AFTER 04-05Z. BRIEF
MVFR CONDITIONS WILL BE POSSIBLE IF A STORM DIRECTLY IMPACTS ONE
OF THE TERMINALS. MVFR CONDITIONS SHOULD PREVAIL AFTER 10-11Z AS
GOOD BL MOISTURE ADVECTS NORTH AND EAST WITH EASTERLY FLOW
DEVELOPING ACROSS THE AREA. THERE IS STILL A LOT OF SPREAD IN
GUIDANCE ON FRONTAL TIMING FRIDAY...WITH NAM SLOWER AND HOLDING
STRATUS/FOG ON LONGER. NAM/MET WOULD ALSO INDICATE SIGNIFICANTLY
LOWER CIGS OVER BOTH TERMINALS. THIS IS THE OUTLIER...SO
CONFIDENCE IS HIGHER THAT CONDITIONS SHOULD IMPROVE TO VFR BY MID
MORNING OVER KGLD AND AROUND 18Z AT KMCK.
&&
.CLIMATE...
ISSUED AT 245 AM MDT THU MAY 24 2012
RECORD AND NEAR RECORD HIGH TEMPERATURES EXPECTED SATURDAY.
GOODLAND.....97 IN 2006
HILL CITY....99 IN 1912
MCCOOK.......98 IN 1967
BURLINGTON...95 IN 1942
YUMA.........96
TRIBUNE......101
COLBY........98
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR/FOLTZ
LONG TERM...FOLTZ
AVIATION...DR
CLIMATE...007
AREA FORECAST DISCUSSION
NWS GOODLAND KS
127 PM MDT THU MAY 24 2012
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 125 PM MDT THU MAY 24 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
EXTENDING FROM THE PACIFIC NORTHWEST ACROSS T HE NORTHERN
PLAINS...WITH WEST/SOUTHWEST FLOW OVER THE CENTRAL ROCKIES AND
CENTRAL HIGH PLAINS. A SERIES OF SHORTWAVE TROUGHS ARE CURRENTLY
TRACKING WITHIN THE MEAN FLOW WITH SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH THESE FEATURES OVER NORTHERN COLORADO AND NORTH
CENTRAL NEBRASKA. A STATIONARY FRONT EXTENDS FROM EASTERN KANSAS
SOUTH INTO NORTHCENTRAL TEXAS...AND THEN NORTH INTO SOUTHCENTRAL
COLORADO.
A CLOSED LOW CENTER WITHING THE LARGE SCALE TROUGH WILL MOVE
EAST/NORTHEAST INTO THE NORTHERN PLAINS WITH LARGE SCALE ASCENT
SPREADING SOUTH AND EAST TOWARDS SOUTHWEST NEBRASKA. THE
STATIONARY FRONT TO THE SOUTH WILL BEGIN TO MOVE NORTH IN RESPONSE
TO STRENGTHENING LEE TROUGH OVER EASTERN COLORADO. A STRONG LLJ IS
ADVERTISED TO DEVELOP BY 06Z TONIGHT WHICH COULD ALSO ACT AS A
FOCUS FOR SHOWER THUNDERSTORM DEVELOPMENT OVER OUR CWA. VERY
STRONG SHEAR WILL DEVELOP OVERNIGHT ALONG WITH ELEVATED
INSTABILITY NEAR THE NOSE OF THE LLJ. BEST FORCING LOOKS TO
BE EITHER NORTH OR SOUTH OF THE CWA. IM ALSO NOT SURE ABOUT HOW
MUCH TD WILL RECOVER NORTH OF THE FRONT. I KEPT POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORY...WITH BEST COVERAGE LATE TONIGHT WHEN LLJ
IS EXPECTED TO DEVELOP. THERE CONTINUES TO BE INDICATION OF FOG
DEVELOPMENT WITH EASTERLY FLOW AROUND SUNRISE TOMORROW...SO I KEPT
PATCHY FOG MENTION.
FRIDAY..SHOWER/THUNDERSTOM ACTIVITY SHOULD COME TO AN END FROM
THE SOUTHWEST TO THE NORTHEAST THROUGH THE DAY...WITH ACTIVITY
POSSIBLY LINGERING OVER NORTHERN PARTS OF THE FORECAST AREA INTO
FRIDAY EVENING. THERE IS A LARGE SPREAD IN GUIDANCE ON TIMING OF
WARM FRONT FRIDAY WITH NAM THE SLOW OUTLIER. NAM SOLUTION WOULD
KEEP STRATUS/FOG IN PLACE ALONG WITH MUCH COOLER AIRMASS.
GFS/ECMWF FAVOR THE CLEARING SOLUTION ALONG WITH MUCH WARMER
TEMPERATURES ACROSS THE SOUTHWEST..WHICH IS WHERE I LEANED THIS
FORECAST CYCLE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 245 AM MDT THU MAY 24 2012
FRIDAY NIGHT-SATURDAY NIGHT...WINDS BECOME SOUTH/SOUTHWEST AS WARM
FRONT LIFTS NORTH OF THE AREA FRIDAY NIGHT. ON SATURDAY INCREASING
PRESSURE GRADIENT BETWEEN LIFTING UPPER LOW INTO IDAHO AND UPPER
HIGH ACROSS THE SOUTH WILL PRODUCE VERY WINDY CONDITIONS. JUST HOW
WINDY IS THE QUESTION. SHOULD SEE SOLID ADVISORY CRITERIA WINDS
ACROSS MUCH OF THE AREA...CANT COMPLETELY RULE OUT WARNING
CRITERIA GUSTS JUST YET. HIGH TEMPERATURES WELL INTO THE 90S. MAY
SEE A FEW STRONG TO SEVERE THUNDERSTORMS DURING THE AFTERNOON AND
EVENING HOURS ALONG AND EAST OF THE DRYLINE WHICH RIGHT NOW IS
EXPECTED EAST OF THE CO/KS BORDER.
SUNDAY...UPPER LOW LIFTS INTO MONTANA WITH SOUTHWEST FLOW AHEAD OF
IT. SLIGHTLY COOLER TEMPERATURES IN THE 80S GENERALLY EXPECTED AS
SFC HIGH SLOWLY MOVES INTO THE AREA. WILL CONTINUE WITH SLIGHT
CHANCE/LOW CHANCE POPS ACROSS THE EASTERN 1/3 OF THE AREA WHERE
FRONT IS EXPECTED.
MONDAY...DRY WITH HIGHS IN THE UPPER 70S TO LOW 80S.
TUESDAY...SMALL CHANCES FOR PRECIPITATION AS A WEATHER SYSTEM
MOVES ACROSS THE AREA. HIGHS IN THE LOW TO MID 80S.
WEDNESDAY...SLIGHTLY COOLER TEMPERATURES WITH AN INCREASING CHANCE
FOR PRECIPITATION AS ANOTHER WEATHER SYSTEM MOVES DOWN FROM THE
NORTH AND NORTHWEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1145 AM MDT THU MAY 24 2012
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT BOTH KGLD AND KMCK
TERMINALS THROUGH LATE TONIGHT. SHOWERS AND THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE AREA TONIGHT. BASED ON EXPECTED SCATTERED
COVERAGE I INCLUDED VCTS AT BOTH TERMINALS AFTER 04-05Z. BRIEF
MVFR CONDITIONS WILL BE POSSIBLE IF A STORM DIRECTLY IMPACTS ONE
OF THE TERMINALS. MVFR CONDITIONS SHOULD PREVAIL AFTER 10-11Z AS
GOOD BL MOISTURE ADVECTS NORTH AND EAST WITH EASTERLY FLOW
DEVELOPING ACROSS THE AREA. THERE IS STILL A LOT OF SPREAD IN
GUIDANCE ON FRONTAL TIMING FRIDAY...WITH NAM SLOWER AND HOLDING
STRATUS/FOG ON LONGER. NAM/MET WOULD ALSO INDICATE SIGNIFICANTLY
LOWER CIGS OVER BOTH TERMINALS. THIS IS THE OUTLIER...SO
CONFIDENCE IS HIGHER THAT CONDITIONS SHOULD IMPROVE TO VFR BY MID
MORNING OVER KGLD AND AROUND 18Z AT KMCK.
&&
.FIRE WEATHER...
ISSUED AT 245 AM MDT THU MAY 24 2012
CRITICAL FIRE WEATHER CONDITIONS REMAIN POSSIBLE SATURDAY AS SFC
WINDS GUSTS OVER 45 MPH AND RH VALUES DROP WELL BELOW 20 PERCENT.
QUESTION BECOMES GREEN-UP CONDITIONS AND IMPACT OF LAST NIGHT/THIS
MORNINGS RAINFALL ACROSS PARTS OF THE AREA AND ONE HOUR FUELS. NO
HIGHLITES ISSUED AT THIS TIME.
&&
.CLIMATE...
ISSUED AT 245 AM MDT THU MAY 24 2012
RECORD AND NEAR RECORD HIGH TEMPERATURES EXPECTED SATURDAY.
GOODLAND.....97 IN 2006
HILL CITY....99 IN 1912
MCCOOK.......98 IN 1967
BURLINGTON...95 IN 1942
YUMA.........96
TRIBUNE......101
COLBY........98
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...007
AVIATION...DR
FIRE WEATHER...007
CLIMATE...007
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1237 PM CDT THU MAY 24 2012
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1234 PM CDT THU MAY 24 2012
A 500MB UPPER LEVEL RIDGE/HIGH WAS LOCATED ACROSS THE EASTERN
UNITED STATES WHILE AN UPPER LEVEL TROUGH EXTENDED FROM WESTERN
CANADA INTO THE NORTHWESTERN UNITED STATES. ONE UPPER LEVEL JET
STREAK WAS PLACED ACROSS COLORADO AND UTAH WITH AN UPPER LEVEL
DISTURBANCE LOCATED IN EASTERN WYOMING. ANOTHER UPPER LEVEL JET
WAS LOCATED ON THE SOUTHWEST SIDE OF A COLD (-26 TO -27C) UPPER
LOW THAT WAS NEAR THE COAST OF BRITISH COLUMBIA. 500MB INDICATED 90
METER HEIGHT FALLS FROM THE NORTH PLATTE SOUNDING AT 12Z. A 700MB
BAROCLINIC ZONE STRETCHED FROM SOUTHEAST COLORADO INTO SOUTHEAST
NEBRASKA WITH THE ELEVATED MIX LAYER LOCATED ACROSS OKLAHOMA AND
EASTERN KANSAS. A SURFACE COLD FRONT AT 12Z EXTENDED FROM
PANHANDLE OF TEXAS ACROSS SOUTHWEST OKLAHOMA INTO SOUTHEAST
KANSAS. ALONG AND EAST OF THIS FRONT SURFACE DEWPOINTS WERE IN THE
MID-UPPER 60S AND 850MB DEWPOINT RANGED FROM 13 TO 16C.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 408 AM CDT THU MAY 24 2012
THE SHORTER TERM MODELS OF THE NAM AND THE HRRR NOW SHOW THERE WILL
NOT BE ANY PRECIP IN OUR FORECAST AREA TODAY. THE COLD FRONT IS
THROUGH OUR CWA, WITH A LOW PRESSURE SYSTEM POSITIONED OVER
SOUTHEAST COLORADO. AN UPPER LEVEL DISTURBANCE IS MOVING
EAST-NORTHEAST BUT TRAVELING THROUGH AREAS NORTH OF OUR COUNTY
WARNING AREA, NORTHERN KANSAS AND NEBRASKA AND POINTS
NORTHEASTWARD. THERE IS SOME CIRRUS AROUND AND THINK THE GRIDS WILL
PRODUCE MOSTLY SUNNY CONDITIONS. WHEN THE FRONT FIRST WENT THROUGH,
THE WINDS BEHIND THE FRONT QUICKLY PICKED UP INTO ADVISORY LEVELS,
AND THUS A SHORT TERM WIND ADVISORY WAS ISSUED FOR THAT AREA WEST OF
A DIGHTON TO MONTEZUMA LINE, AND ALSO NORTH OF A JOHNSON CITY TO
MONTEZUMA LINE. AT THE TIME OF WRITING THIS SHORT TERM DISCUSSION,
WINDS HAD FALLEN BACK TO LESS THAN ADVISORY CRITERIA AT ALL SITES
EXCEPT HUGOTON AND SCOTT CITY. THIS WIND ADVISORY WILL EXPIRE AT
09Z, AND SHOULD NOT SHOW UP IN THE NEXT ZONE ISSUANCE. TEMPERATURES
TODAY WILL BE COOLER THAN YESTERDAY`S NEAR CENTURY MARKS, DUE TO THE
COLD FRONTAL PASSAGE AND HIGH CLOUDS. HIGHS TODAY SHOULD RANGE FROM
THE MID 80S ALONG THE OKLAHOMA PANHANDLE TO THE UPPER 70S NORTH OF
THE I-70 CORRIDOR.
THE COLD FRONT MENTIONED ABOVE WILL COME BACK NORTH TONIGHT AS A
WARM FRONT. JUST HOW FAST NORTH IT WILL MOVES IS HANDLED
DIFFERENTLY BY THE MODELS. THE NAM MODEL BRINGS THE FRONT NORTH THE
FASTEST, WITH THE GFS AND ECMWF MODELS SLOWER. BY THE TIME THE
FRONT REACHES OUR NORTHERN COUNTIES OF ELLIS, TREGO, RUSH, NESS,
LANE AND SCOTT BY 09Z, THERE COULD BE A FEW THUNDERSTORMS FORM IN
THE ELEVATED UNSTABLE LAYERS OF THE ATMOSPHERE. I ONLY PLACED 20
POPS IN, AS THE TIMING OF THE FRONT IS STILL IN QUESTION. CLOUDS
WILL BLANKET MOST OF SOUTHWESTERN KANSAS THURSDAY NIGHT, AND WINDS
NEAR THE OKLAHOMA BORDER WILL BE SOUTH AT 10 TO 20 MPH BEHIND THE
FRONT AND EASTERLY AT 10 TO 20 MPH NORTH OF THE FRONT. TEMPERATURES
THURSDAY NIGHT
WILL BE SOMEWHAT ELEVATED, ONLY FALLING TO THE MID 60S IN THE
MEDICINE LODGE AND PRATT AREAS, INTO THE LOWER 60S FROM LIBERAL TO
DODGE CITY TO LARNED, AND INTO THE MIDDLE 50S FROM SYRACUSE TO SCOTT
CITY TO WAKEENEY.
.LONG TERM...(FRIDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT THU
MAY 24 2012
A CHALLENGING FORECAST LIES AHEAD FOR THE COMING SEVERAL DAYS, AS A
FEW OPPORTUNITIES FOR CONVECTION APPEAR POSSIBLE. BY FRIDAY MORNING,
A WARM FRONT WILL BE LIFTING NORTHWARD THROUGH SOUTHWEST KANSAS. THE
MODELS DIFFER SIGNIFICANTLY WITH THIS FRONT. THE GFS PRODUCES QPF AS
EARLY AS OVERNIGHT THURSDAY HEADING INTO FRIDAY MORNING, AND REALLY
INCREASING THE QPF AROUND THE 12Z TIMEFRAME. BY CONTRAST THE NAM AND
ECMWF ARE MORE IN LINE WITH A DRY SOLUTION. THE CONVECTION PRODUCED
IN THESE CASES ARE MORE IN LINE WITH THE EDGE OF A CAPPING LATER IN
THE MID LEVELS THAT IS LOCATED ACROSS NORTHERN KANSAS. IN EITHER
CASE; STRONG LOW LEVEL THETA-E ADVECTION AND ISENTROPIC LIFT IN THE
MORNING, OR BREAKING THE CAP LATE IN THE DAY FARTHER NORTH, QUARTER
TO GOLFBALL SIZED HAIL WOULD BE LIKELY. HOWEVER, THE MOST LIKELY
EVENT IS PROBABLY ALONG THE LINES OF THE ECMWF AND NAM GIVEN THE
WARM TEMPERATURES IN THE MID LEVELS OF 13 TO 14 DEGREES C. IF THE
WARM AIR ALOFT IS STRONG ENOUGH OF A CAP ON FRIDAY, THE POTENTIAL
FOR SEVERE CONVECTION MIGHT BE RELEGATED EVEN FARTHER NORTH INTO
NORTH CENTRAL KANSAS AND NEBRASKA. SURFACE TEMPERATURES WILL EXCEED
95 DEGREES IN THIS WARM BOUNDARY LAYER AIR AND LIKELY HIT 100
DEGREES OR MORE IN THE RED HILLS REGION. IT IS UNKNOWN AT THIS TIME
IF THE SMOKE FROM THE NEW MEXICO FIRES WILL PLAY A ROLE IN
INHIBITING INSOLATION WHICH IN TURN COULD PREVENT TEMPERATURES FROM
REACHING THE AFOREMENTIONED VALUES. BUT IT IS SOMETHING TO CONSIDER
IN THE NEXT 24 OR SO HOURS.
HEADING INTO THE WEEKEND, A CONSENSUS OF THE MODELS WOULD SEEM TO
SUPPORT AT LEAST SOME POTENTIAL FOR DRYLINE TRIGGERED CONVECTION
ACROSS CENTRAL KANSAS ON SATURDAY. HOWEVER, IT IS NOT CLEAR AT ALL
JUST WHERE THE DRYLINE MIGHT BE LOCATED AT THIS TIME. GENERALLY
ISOLATED DISCREET CONVECTION WITHIN AMPLE SHEAR FOR AT LEAST THE
POTENTIAL FOR SUPERCELLS PRODUCING UP TO GOLFBALL SIZED HAIL.
A MORE ORGANIZED SEVERE CONVECTIVE POTENTIAL COULD OCCUR ON SUNDAY.
THE FORCING MECHANISMS FOR THIS POTENTIAL WILL BE AN ADVANCING UPPER
TROUGH WITH A LARGE COLD POOL (COOLING TEMPERATURES ALOFT) AND A
LEAD UPPER JET`S RIGHT REAR QUADRANT. THE GFS AND ECMWF BOTH APPEAR
TO SUPPORT A TORNADIC SUPERCELL ENVIRONMENT SUNDAY AFTERNOON ALONG
THE WARM FRONT-SURFACE LOW INTERSECTION.
BEYOND THIS PERIOD, THE FORECAST APPEARS TO CREATE MORE UNCERTAINTY.
THE OVERALL CONSENSUS APPEARS TO BE A FLATTENING OF THE UPPER FLOW
AS THE UPPER JET LIFTS INTO THE UPPER MIDWEST THROUGH TUESDAY. THIS
SHOULD, WITH TIME ALLOW DRIER AIR TO SETTLE OVER WESTERN KANSAS
REDUCING THE ODDS OF THUNDERSTORMS. BEFORE THE ECMWF AND GFS BOTH
TREND RAPIDLY TOWARD STRONG MOISTURE RETURN AND CONVECTION ONCE
AGAIN BY AROUND DAY 7.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1234 PM CDT THU MAY 24 2012
WINDS THIS AFTERNOON WILL CONTINUE TO SUBSIDE AS A RIDGE OF HIGH
PRESSURE AT THE SURFACE BUILDS ACROSS WESTERN KANSAS. TOWARDS
EVENING AN EASTERLY WIND WILL DEVELOP AS SURFACE PRESSURES BEGIN
TO FALL ALONG EASTERN COLORADO/NORTHEAST NEW MEXICO. ISENTROPIC
LIFT AND MOISTURE WILL THEN BEGIN TO IMPROVE ACROSS WESTERN KANSAS
EARLY TONIGHT AND BASED ON BUFR SOUNDINGS THE LOWER LEVELS WILL
BEGIN TO SATURATE AFTER MIDNIGHT WITH MVFR CIGS DEVELOPING AFTER
09Z AT DDC AND GCK. CLOUD BASES APPEAR TO BE SLIGHTLY HIGHER AT
HYS. BASED ON THE DEPTH OF THIS MOIST LAYER FROM THE NAM THESE LOW
CLOUDS ARE EXPECTED TO ERODE TOWARDS LATE MORNING AS A
SOUTHEAST/EAST WIND CONTINUES AT NEAR 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 83 62 98 70 / 0 10 10 10
GCK 82 60 97 68 / 0 10 10 10
EHA 85 59 93 66 / 0 10 10 10
LBL 85 62 96 68 / 0 10 10 10
HYS 80 59 89 69 / 10 20 20 20
P28 85 67 96 72 / 0 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT THU MAY 24 2012
.UPDATE...
ISSUED AT 1148 AM EDT THU MAY 24 2012
ISSUED A WIND ADVISORY FOR THE REST OF CENTRAL AND ERN CWA AS WINDS
WERE ALREADY GREATER THAN PREVIOUS FORECAST...AND A CORE OF 40-50KT
925MB WINDS WILL MOVE INTO THE CENTRAL AND ERN CWA AROUND 18Z.
EXPECT GUSTS TO AROUND 45KTS TO BE ABLE TO MIX DOWN TO THE SFC THIS
AFTERNOON. STILL WATCHING SEVERE THUNDERSTORM POTENTIAL THIS
AFTERNOON/EVENING OVER MAINLY THE WESTERN HALF OF UPPER MI. WILL BE
EXAMINING POPS/WX MORE CLOSELY FOR UPDATES IN THE NEXT COUPLE OF
HOURS.
&&
.SYNOPSIS...
ISSUED AT 504 AM EDT THU MAY 24 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE UPR
RDG OVER THE NE CONUS/SE CANADA DOWNSTREAM OF DEEP UPR TROF IN THE
ROCKIES. UNDER THE SW FLOW ALF BTWN THESE LARGER SCALE FEATURES...A
SHRTWV/SFC LO LIFTING NEWD NEAR LK WINNIPEG WITH UPR DVGC IN RRQ OF
SUPPORTING 100KT H3 JET MAX HAS CAUSED QUITE A BIT OF SHRA/TS IN MN
MAINLY WITHIN AXIS OF DEEPER MSTR ON THE COLD SIDE OF SFC FNT OVER
WRN LK SUP THAT IS ATTENDANT TO LK WINNIPEG LO. A FEW -SHRA/A LTG
STRIKE OF TWO ARE JUST W OF IWD NEAR THE SFC COLD FNT LOCATION NOT
FAR FM ASHLAND IN NW WI. TO THE E OVER MOST OF THE CWA...BONE DRY
AIRMASS SHOWN ON THE 00Z GRB RAOB /PWAT 0.25 INCH WITH KINX -53/ IS
BRINGING A TRANQUIL OVERNGT WITH JUST SOME SCT HI CLDS. THE APRCH OF
ANOTHER STRONG SHRTWV ROTATING THRU THE WRN TROF IS CAUSING MORE
SHRA/TS TO BREAK OUT IN NEBRASKA UNDER EXPANDING AREA OF COOLING CLD
TOPS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 504 AM EDT THU MAY 24 2012
MAIN FCST CONCERN DURING THIS TIME IS POTENTIAL FOR SVR WX LATE THIS
EVNG ASSOCIATED WITH SHRTWV NOW ROUNDING THE BASE OF THE WRN TROF
AND CAUSING EXPANDING AREA OF SHRA/TS AROUND NEBRASKA.
TDAY...ALTHOUGH SOME OF THE SCT -SHRA NOW ALONG THE COLD FNT WL
DRIFT INTO THE WRN ZNS EARLY THIS MRNG PER SLOWLY VEERING H85 FLOW
TO SW AS SHOWN BY THE 00Z NAM...THE BULK OF THE RA NOW IN MN WL STAY
W AND DIMINISH AS POCKET OF UPR DVGC IN RRQ OF JET MAX IN NW ONTARIO
LIFTS TO THE NE. BUT WITH DRYNESS OF AIRMASS IN PLACE PER THE 00Z
GRB RAOB AND HI AMPLITUDE RDG JUST TO THE E...THESE -SHRA SHOULD
REMAIN OVER THE W AS THE SLOW MOVING COLD FNT STALLS WITH BACKING OF
THE UPR FLOW ASSOCIATED WITH MOTION OF ROCKIES SHRTWV INTO THE
PLAINS. THEN MOST OF THE DAY WILL FEATURE A GUSTY S WIND AS H85 WINDS
INCRS TO 40-45KTS IN ADVANCE OF THE SHRTWV/DVLPG SFC LO IN THE
PLAINS THAT IS FCST TO LIFT NEWD TO NOT FAR FM DLH BY 00Z. CONFINED
CHC POPS TO THE W. DAYTIME HEATING/MIXING WL CAUSE WIND GUSTS TO AT
LEAST APRCH ADVY CRITERIA WITH STEEP LLVL LAPSE RATES AS HI TEMPS
SURGE INTO THE 80S AT SOME PLACES AWAY FM THE MODERATING INFLUENCE
OF MAINLY LK MI. AFT COORDINATION WITH GRB...OPTED TO ISSUE WIND
ADVY FOR MAINLY THE W HALF OF THE CWA AWAY FM THE MORE STABILIZED
KEWEENAW PENINSULA TO ACCOUNT FOR DEEP MIXING...EXCEPTIONAL
INTENSITY OF THE APRCHG DISTURBANCE/SFC LO PRES...AND GFS FCST
H85/H925 S WINDS UP TO 60KTS/50KTS. GFS BUFKIT PROFILES INDICATE
WINDS OF 35-40 KTS WL BE PRESENT IN MIXED LYR AT IWD. ALTHOUGH THE
ARRIVAL OF HIER H95-9 SPECIFIC HUMIDITY IN THIS STRENGTHENING SLY
FLOW WL KEEP MIN RH FM FALLING TO CRITICAL LVLS...THE GUSTY S WINDS
WL STILL BE A CHALLENGE FOR THE PERSONNEL FIGHTING THE SENEY
FIRE/OTHER WILDFIRES. MORE NMRS SHRA/TS ASSOCIATED WITH THE LO
MOVING NEAR DLH MAY ARRIVE OVER THE FAR W IN THE 21Z-24Z TIME.
TNGT...AS THE NEGATIVELY TILTED SHRTWV/SFC LO MOVE QUICKLY NE INTO
ONTARIO...EXPECT A STRONG COLD FROPA ACRS THE CWA. VERY STRONG
DYNAMICS THAT IMPACT MAINLY THE W HALF INCLUDE VIGOROUS DPVA/UPR
DVGC IN THE LEFT EXIT OF SUPPORTING 130KT H3 JET MAX. ALTHOUGH FCST
SDNGS DO NOT SHOW PARTICULARLY STEEP MID LVL LAPSE RATES...INVERTED
V LOOK TO THE T/TD PROFILE IN THE SUB H8-85 LYR FOR IWD AT 00Z WITH
EARLY EVNG FROPA THERE MAXIMIZING LLVL DESTABLIZATION AT PEAK
HEATING TIME SUG THE POTENTIAL FOR DAMAGING WINDS WITH
UNIDIRECTIONAL/SLOWLY VEERING POWERFUL FLOW THAT INCLUDES H7/H85
WINDS AS HI AS 60-70KTS/50-60KTS EVEN THOUGH THERE IS NOT A LOT OF
MID LVL DRY AIR TO MAXIMIZE DCAPE. DESPITE THE STRONG WIND
FIELDS...INVERTED V LLVL T/TD PROFILE AND LACK OF DIRECTIONAL SHEAR
WOULD TEND TO MINIMIZE TORNADO THREAT. SINCE THE MID LVL LAPSE RATES
ARE RELATIVELY WEAK AND LACK OF DRY MID LVL AIR RESULTS IN WBZ HGT
IN THE 12.5-13.0K RANGE...THE LARGE HAIL THREAT DOES NOT APPEAR TOO
HI. SINCE THE SHARPER DYNAMICS WL EXIT TO THE NE AND NOCTURNAL
COOLING WL BEGIN TO HAVE AN IMPACT...EXPECT THE SHRA/TS CHCS AND
SEVERE WX THREAT TO WANE AS THE FRONT MARCHES FARTHER E. VIGOROUS
DRY SLOTTING/ARRIVAL OF LARGER SCALE QVECTOR DVGC IN THE WAKE OF THE
FROPA WL CAUSE DIMINISHING POPS...BUT LINGERING LLVL MSTR MAY STILL
CAUSE A FEW -SHRA IN THE UPSLOPE AREAS OF THE W THRU THE NGT.
GIVEN STRENGTH OF THIS DISTURBANCE...CONCERNED W WINDS IN THE WAKE
OF THE COLD FROPA WL REACH ADVY CRITERIA OVER MAINLY THE EXPOSED
KEWEENAW PENINSULA AFT 06Z WITH W H925 WINDS INCRSG TO 40-50
KTS/VIGOROUS CAD THAT WL MAINTAIN STEEPER LLVL LAPSE RATES DESPITE
SOME STABILIZATION OVER THE RELATIVELY COOL WATERS OF LK SUP/AND
APRCH OF PRES RISE MAX OF 10-15MB/6HRS THAT WL ACCENTUATE
ISALLOBARIC WIND COMPONENT NEARLY IN LINE WITH GRADIENT FLOW.
FRI...WITH THE ARRIVAL OF DRIER AIR AND APRCH OF UPR RDG...EXPECT A
DRY DAY. GUSTY WINDS WL PERSIST WITH DAYTIME HEATING/MIXING EVEN
THOUGH THE PRES GRADIENT IS FCST TO SLOWLY SLACKEN. WITH H85 TEMPS
TOPPING OUT IN THE 8-10C RANGE...MIXING TO H75 ON GFS/NAM FCST SDNGS
YIELD HI TEMPS IN THE 75-80 RANGE WITH DOWNSLOPING FLOW AWAY FM LK
MODERATION IN LLVL WNW FLOW.
.LONG TERM...(AFTER MIDNIGHT FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 621 AM EDT THU MAY 24 2012
EXPECT WINDS TO DIMINISH AND BECOME NEARLY CALM FRIDAY NIGHT...AS
TEMPS FALL INTO THE 40S. WENT WITH THE DRIER NON-NAM SOLUTION FOR
MUCH OF THIS PERIOD...AS THE 24/00Z NAM WAS VERY OPTIMISTIC WITH ITS
PRINTOUT OF PRECIP.
OTHER CHANGES INCLUDED A WARMING OF TEMPS UP A COUPLE OF DEGREES FOR
SATURDAY /COOLEST N NEAR LAKE SUPERIOR/...WITH A GENERALLY SLOWER
ONSET OF PRECIP. THUNDERSTORMS SHOULD STAY ALONG THE WI BORDER
THROUGH THE AFTERNOON HOURS. THESE THUNDERSTORMS WILL PUSH
NORTHWARD...THANKS TO THE WARM FRONT. TEMPS SUNDAY WILL POP BACK
INTO THE 70S WEST SUNDAY. WHILE WE DO HAVE A FCST FOR HIGH CHANCE
POPS THROUGH MUCH OF THE DAY...THE BEST CHANCE WILL MORE THAN LIKELY
BE THROUGH 18Z...BEFORE MUCH OF THE PRECIPITATION MOVES N ACROSS
LAKE SUPERIOR. THUNDERSTORMS WILL END W TO E MONDAY AS THE SFC LOW
PUSHES ACROSS AND EXITS E OF THE AREA. WHILE THERE ARE SILL SOME
SIGNIFICANT DIFFERENCES BETWEEN THE MODELS...THEY ARE IN BETTER
AGREEMENT FOR THIS PERIOD THAN 24 HRS AGO. THE SFC TROUGH WILL
LINGER ACROSS THE CWA THROUGH TUESDAY WITH LOW CHANCE/SLIGHT CHANCE
POPS LINGERING THROUGH THE END OF THE FCST PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 141 PM EDT THU MAY 24 2012
CHALLENGING FORECAST THIS AFTERNOON WITH THUNDERSTORMS AND GUSTY
WINDS ACROSS UPPER MICHIGAN. RADAR SHOWS SHOWERS AND THUNDERSTORMS
TIED TO A FRONTAL BOUNDARY EXTENDING ACROSS WESTERN LAKE SUPERIOR.
THIS BOUNDARY IS ASSOCIATED WITH A LOW PRESSURE SYSTEM CENTERED OVER
CENTRAL IOWA AND SOUTHERN MN. AS THIS SYSTEM MOVES NORTHWARD SHOWERS
AND THUNDERSTORMS WILL SPREAD EASTWARD INTO KIWD AND KCMX LATE THIS
AFTERNOON...AND EVENTUALLY INTO KSAW OVERNIGHT. AS THE PRESSURE
GRADIENT GRADUALLY TIGHTENS WITH THE APPROACH OF THE SYSTEM WINDS
WILL GUST TO AS MUCH AS 35 KNOTS THROUGHOUT THE AFTERNOON TODAY AND
EVEN OVERNIGHT. SHOWERS AND THUNDERSTORMS THAT WILL DEVELOP HAVE THE
POTENTIAL TO BRING EVEN HIGHER GUSTS...POSSIBLY SEVERE...TO THE
SURFACE. ONCE THE SYSTEM PASSES TO THE NORTHEAST OF LAKE SUPERIOR
OVERNIGHT WINDS WILL BECOME MORE WESTERLY. GUSTS ACROSS THE
KEWEENAW/AT KCMX/ FRIDAY MORNING COULD REACH AS HIGH AS 40
KNOTS...AND SHOULD WEAKEN THROUGH LATE AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 621 AM EDT THU MAY 24 2012
ALTHOUGH S WINDS AT SOME OF THE HIGHER PLATFORMS LIKE STANNARD ROCK
WILL PUSH 30-35 KTS INTO TONIGHT IN ADVANCE OF A DEEP LO PRES/STRONG
COLD FRONT MOVING THRU WESTERN LK SUP THIS EVENING...HIGHER OVER
WATER STABILITY WILL LIMIT THE MIXING OF THE STRONGER WINDS TO NEAR
THE SURFACE. ONCE THE FRONT PASSES BY TONIGHT AND THE WIND SHIFTS TO
THE W...EXPECT THE STRONGER WINDS TO MIX CLOSER TO THE SURFACE WITH
THE ARRIVAL OF COOLER AIR. ALTHOUGH THERE IS SOME UNCERTAINTY HOW
MUCH OF THE STRONGER FLOW WILL MAKE IT TO THE SURFACE...OPTED TO
ISSUE GALE WATCH LATE TONIGHT THRU FRI MORNING FOR THE AREA BETWEEN
ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN WILL ENHANCE THE EXPECTED
WSW FLOW. WINDS WILL DIMINISH ON FRI AFTERNOON WITH WEAKENING PRES
GRADIENT.
HIGH PRESSURE ACROSS CENTRAL CANADA FRIDAY NIGHT WILL CROSS ONTARIO
AND LAKE SUPERIOR SATURDAY...BEFORE SETTLING ACROSS HUDSON BAY ON
SUNDAY. LOW PRESSURE OVER THE NORTHERN PLAINS SUNDAY WILL FILL
ACROSS THE UPPER GREAT LAKES MONDAY INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR MIZ002-
004>007-009>014-084-085.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR LSZ263-
264-266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...TITUS
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...KF
AVIATION...MCB
MARINE...KF
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
403 PM EDT THU MAY 24 2012
.SYNOPSIS...
THE COMBINATION OF BUILDING RIDGE ALOFT AND WEAK SURFACE HIGH
PRESSURE WILL RESULT IN PARTLY CLOUDY SKIES TONIGHT WITH SOME AREAS
OF PATCHY FOG. ON FRIDAY...SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS THE SAINT LAWRENCE VALLEY IN THE LATE AFTERNOON
HOURS AND SPREAD EAST INTO VERMONT DURING THE EVENING. SOME STORMS
COULD BE STRONG WITH GUSTY WINDS...SMALL HAIL...AND BRIEF HEAVY
DOWNPOURS....ESPECIALLY ACROSS NORTHERN NEW YORK. SLIGHTLY COOLER
AND DRIER AIR ARRIVES FOR SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 400 PM EDT THURSDAY...FCST FOCUS WL BE AREAL COVERAGE OF CLOUDS/FOG AGAIN
TONIGHT...FOLLOWED BY CHCS FOR CONVECTION LATE FRIDAY. WATER VAPOR
SHOWS LARGE AREA OF SUBSIDENCE ACRS OUR CWA THIS AFTN ASSOCIATED
WITH BUILDING MID/UPPER LVL RIDGE. MEANWHILE...MID/UPPER LVL TROF
AND S/W ENERGY IS COMBINING WITH A SFC COLD FRNT TO PRODUCE AREAS OF
CONVECTION UPSTREAM ACRS THE NORTHERN PLAINS/WESTERN GREAT LAKES.
THIS ENERGY/MOISTURE AND SFC BOUNDARY WL BE APPROACHING OUR WESTERN
FA BTWN 18Z-21Z FRIDAY...WITH INCREASING CHCS FOR STORMS. RAP AND
LOCAL 4KM SOUNDINGS ONCE AGAIN SHOW PLENTY OF SFC TO 850MB RH
DEVELOPING LATE THIS EVENING ACRS CENTRAL/EASTERN VT ASSOCIATED WITH
MOIST SE FLW. THIS WL CREATE AREAS OF LOW CLOUDS AND MIST...NOT
THINKING AS MUCH FOG TONIGHT...DUE TO BL WINDS OF 8 TO 12 KNTS.
ALSO...AREAS ACRS CENTRAL/EASTERN VT AND NORTHERN DACKS THAT RECEIVE
ISOLATED RAIN THIS AFTN...WL HAVE A BETTER CHC FOR FOG TONIGHT.
OTHERWISE...BL STAYS MIXED OVERNIGHT ACRS THE CPV/SLV AND SFC DWPTS
IN THE U50S/L60S WL RESULT IN LOWS BTWN 60 AND 65F...WITH MAINLY 50S
IN THE COOLER MTN VALLEYS.
ON FRIDAY...POTENT S/W ENERGY AND SFC COLD FRNT WL APPROACH OUR
WESTERN CWA BTWN 18Z-21Z. LEFTOVER MORNING CLOUDS SHOULD DISSIPATE
BY 15Z...WITH SFC TEMPS WARMING INTO THE U70S TO M80S AHEAD OF
BOUNDARY. THIS WL CREATE AN AXIS OF INSTABILITY WITH CAPE VALUES
NEAR 1400 J/KG...LIS AROUND -3C...AND TT`S NEAR 50. IN ADDITION...0
TO 3KM AND 0 TO 6KM SHEAR INCREASES ACRS OUR WESTERN CWA ON FRIDAY
AFTN...AS JET ENERGY FROM MID/UPPER LVL TROF APPROACHES. BOTH THE
NAM/GFS SHOW 0 TO 3KM VALUES AROUND 30 KNTS AND 0 TO 6KM SHEAR
VALUES NEAR 40 KNOTS. HOWEVER...RIBBON OF DEEP LAYER MOISTURE WL BE
WEAKENING ACRS OUR CWA...AS SYSTEM ENCOUNTERS STRONG MID/UPPER LVL
RIDGE AND BEST ULVL DYNAMICS WL BE SHIFTING TWD HUDSON BAY...INSTEAD
OF DIGGING SE ACRS THE EASTERN GREAT LAKES. THESE FACTORS WL LIMIT
AREAL COVERAGE/INTENSITY OF CONVECTION...ALONG WITH TIMING OF SFC
BOUNDARY AFT 00Z FOR CPV/VT...WITH INSTABILITY PARAMETERS WEAKENING.
THE BEST CHC FOR A STRONG STORM OR TWO WL BE NORTHERN NEW YORK WITH
DIME SIZE HAIL AND WIND GUST TO 50 MPH POSSIBLE BTWN 18Z-22Z.
OTHERWISE...BROKEN LINE OF SHOWERS WITH EMBEDDED STORMS WL ENTER THE
CPV BY 00Z AND BE THRU VT BY 06Z SATURDAY. PROGGED 85H TEMPS NEAR
14C AND 925MB TEMPS AROUND 18C SUPPORT HIGHS BACK INTO THE M70S
MTNS/NEK TO L/M 80S WARMER VALLEYS. FINALLY...SOUNDINGS SHOW GUSTY
SOUTH TO SOUTHWEST WINDS BTWN 15 AND 25 MPH WITH GUSTS TO 30 MPH.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 400 PM EDT THURSDAY...SFC COLD FRNT SWEEPS ACRS OUR CWA ON FRIDAY
NIGHT...WHILE HIGH PRES BUILDS INTO OUR FA BY SATURDAY. LLVL CAA
WL DEVELOP BEHIND SFC BOUNDARY FRIDAY NIGHT INTO SATURDAY WITH
BEST RH PROFILES MOVING EAST OF OUR CWA BY 12Z SAT. THE
COMBINATION OF BL WINDS AND CAA WL LIMIT AREAL COVERAGE OF FOG/BR
ON SATURDAY MORNING...BUT FEEL A FEW OF THE SHELTERED VALLEYS WL
SEE SOME FOG. TEMPS WL COOL INTO THE 40S MTN VALLEYS TO M/U50S
CPV/SLV ON SAT MORNING. HIGH PRES AND SUBSIDENCE ALOFT WL RESULT
IN PLENTY OF SUN ON SATURDAY WITH SOME FAIR WX CUMULUS POSSIBLE
ACRS THE MTNS AS CONVECTIVE TEMPS ARE REACHED. PROGGED 85H TEMPS
COOL BTWN 6-8C ON SATURDAY...SUPPORTING HIGHS ONLY IN THE 60S MTNS
TO L/M70S VALLEYS. SATURDAY NIGHT...AREAS OF FOG WL BE
POSSIBLE...ALONG WITH SOME HIGH LVL DEBRIS CLOUDS ACRS NORTHERN NY
FROM UPSTREAM CONVECTION. WL KEEP FCST DRY WITH TEMPS COOLING BACK
INTO THE 40S MTNS TO M/U50S CPV/SLV. NORTHERLY WINDS SHOULD BECOME
LIGHT AND VARIABLE OVERNIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 350 PM EDT THURSDAY...GUIDANCE POINTS TO A RATHER ACTIVE
PERIOD OF WEATHER FOR LATE MEMORIAL DAY WEEKEND INTO TUESDAY. THE
POTENTIAL EXISTS FOR ONE OR SEVERAL ROUNDS OF SHOWERS OR
THUNDERSTORMS DURING THIS PERIOD...ACCOMPANIED BY ABOVE-AVERAGE
TEMPERATURES AND RATHER HUMID WEATHER. CONVECTIVE SCENARIO WILL
DEPEND ON THUNDERSTORMS FROM PREVIOUS DAYS...SO IT IS DIFFICULT TO
PINPOINT SPECIFICS AT THIS TIME. IT APPEARS THAT MONDAY AND/OR
TUESDAY OFFER THE BEST POTENTIAL FOR THUNDER AS SHOWALTER INDICES
DROP BELOW ZERO (ESPECIALLY ON MONDAY) WITH RATHER STRONG UPPER-
LEVEL FLOW ALOFT. REGARDING TEMPERATURES...850MB TEMPERATURES
STEADILY RISE FROM 12-13 C ON SUNDAY TO AROUND 14-16 C ON
TUESDAY...LEADING TO HIGHS RISING FROM THE UPPER 70S TO THE
LOWER/MID 80S WITH LOWS IN THE UPPER 50S TO THE LOWER/MID 60S.
TEMPERATURES ON MONDAY APPEAR PARTICULARLY TRICKY EAST OF THE
GREENS GIVEN FORECAST COOLER THICKNESSES THERE...SO HAVE KEPT
HIGHS IN THE MID 70S IN THE NORTHEAST KINGDOM ON MONDAY.
COLD FRONT LOOKS TO SWEEP ACROSS THE NORTH COUNTRY LATER
TUESDAY...BRINGING WITH IT NOTICEABLY COOLER AND DRIER WEATHER TO
THE REGION FOR WEDNESDAY INTO THE REMAINDER OF THE EXTENDED.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THROUGH 18Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR
PERHAPS A THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME
INSTABILITY IN PLACE BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR
NOW. EXPECTING MAINLY VFR FOR TONIGHT THOUGH SOME 3SM BR WITH
ASSOCIATED MVFR/IFR CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT
WINDS TONIGHT THINK THAT THERE WILL BE ENOUGH TURBULENT MIXING TO
LIMIT FOG FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...LOCONTO
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
350 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 114 PM EDT THURSDAY...NO SIGNIFICANT CHANGES TO CRNT FCST
WITH TEMPS WARMING INTO THE M70S SOUTHERN VT TO M80S IN THE SLV.
THIS SFC HEATING HAS CREATED CAPE VALUES BTWN 1200 AND 1600
J/KG...BUT WATER VAPOR SHOWS BUILDING RIDGE AND STRONG AREA OF
SUBSIDENCE ACRS OUR CWA. THIS WL RESULT IN LIMITED AREAL COVERAGE
OF CONVECTION THIS AFTN...WITH BEST CHC ALONG THE SPINE OF THE
GREEN MTNS AND ACRS PARTS OF NORTHERN NY. WL CONT TO MENTION SCHC
TO CHC POPS ACRS THESE REGIONS.
FCST IN GREAT SHAPE THIS MORNING WITH ONLY MINOR CHANGES NEEDED.
VIS SATL PIC SHOWS LOW CLOUDS SLOWLY DISSIPATING ACRS
EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT AS SFC HEATING
CONTS THESE CLOUDS WL DEVELOP INTO A SCATTERED/BROKEN
CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV 4KM SHOWS SOME
INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM INTO THE U70S
TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI VALUES NEAR
-3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF SUBSIDENCE AND
ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER LVL RIDGE ACRS
OUR REGION. THIS WL LIMIT AREAL COVERAGE OF CONVECTION THIS
AFTN...THINKING JUST A SCHC DACKS/SLV AND CENTRAL/EASTERN VT
ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST OF CWA WL BE
RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO L80S CPV TO M/U
70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 350 PM EDT THURSDAY...GUIDANCE POINTS TO A RATHER ACTIVE
PERIOD OF WEATHER FOR LATE MEMORIAL DAY WEEKEND INTO TUESDAY. THE
POTENTIAL EXISTS FOR ONE OR SEVERAL ROUNDS OF SHOWERS OR
THUNDERSTORMS DURING THIS PERIOD...ACCOMPANIED BY ABOVE-AVERAGE
TEMPERATURES AND RATHER HUMID WEATHER. CONVECTIVE SCENARIO WILL
DEPEND ON THUNDERSTORMS FROM PREVIOUS DAYS...SO IT IS DIFFICULT TO
PINPOINT SPECIFICS AT THIS TIME. IT APPEARS THAT MONDAY AND/OR
TUESDAY OFFER THE BEST POTENTIAL FOR THUNDER AS SHOWALTER INDICES
DROP BELOW ZERO (ESPECIALLY ON MONDAY) WITH RATHER STRONG UPPER-
LEVEL FLOW ALOFT. REGARDING TEMPERATURES...850MB TEMPERATURES
STEADILY RISE FROM 12-13 C ON SUNDAY TO AROUND 14-16 C ON
TUESDAY...LEADING TO HIGHS RISING FROM THE UPPER 70S TO THE
LOWER/MID 80S WITH LOWS IN THE UPPER 50S TO THE LOWER/MID 60S.
TEMPERATURES ON MONDAY APPEAR PARTICULARLY TRICKY EAST OF THE
GREENS GIVEN FORECAST COOLER THICKNESSES THERE...SO HAVE KEPT
HIGHS IN THE MID 70S IN THE NORTHEAST KINGDOM ON MONDAY.
COLD FRONT LOOKS TO SWEEP ACROSS THE NORTH COUNTRY LATER
TUESDAY...BRINGING WITH IT NOTICEABLY COOLER AND DRIER WEATHER TO
THE REGION FOR WEDNESDAY INTO THE REMAINDER OF THE EXTENDED.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THROUGH 18Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR
PERHAPS A THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME
INSTABILITY IN PLACE BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR
NOW. EXPECTING MAINLY VFR FOR TONIGHT THOUGH SOME 3SM BR WITH
ASSOCIATED MVFR/IFR CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT
WINDS TONIGHT THINK THAT THERE WILL BE ENOUGH TURBULENT MIXING TO
LIMIT FOG FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...LOCONTO
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
348 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 114 PM EDT THURSDAY...NO SIGNIFICANT CHANGES TO CRNT FCST
WITH TEMPS WARMING INTO THE M70S SOUTHERN VT TO M80S IN THE SLV.
THIS SFC HEATING HAS CREATED CAPE VALUES BTWN 1200 AND 1600
J/KG...BUT WATER VAPOR SHOWS BUILDING RIDGE AND STRONG AREA OF
SUBSIDENCE ACRS OUR CWA. THIS WL RESULT IN LIMITED AREAL COVERAGE
OF CONVECTION THIS AFTN...WITH BEST CHC ALONG THE SPINE OF THE
GREEN MTNS AND ACRS PARTS OF NORTHERN NY. WL CONT TO MENTION SCHC
TO CHC POPS ACRS THESE REGIONS.
FCST IN GREAT SHAPE THIS MORNING WITH ONLY MINOR CHANGES NEEDED.
VIS SATL PIC SHOWS LOW CLOUDS SLOWLY DISSIPATING ACRS
EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT AS SFC HEATING
CONTS THESE CLOUDS WL DEVELOP INTO A SCATTERED/BROKEN
CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV 4KM SHOWS SOME
INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM INTO THE U70S
TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI VALUES NEAR
-3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF SUBSIDENCE AND
ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER LVL RIDGE ACRS
OUR REGION. THIS WL LIMIT AREAL COVERAGE OF CONVECTION THIS
AFTN...THINKING JUST A SCHC DACKS/SLV AND CENTRAL/EASTERN VT
ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST OF CWA WL BE
RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO L80S CPV TO M/U
70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AS OF 348 PM EDT THURSDAY...GUIDANCE POINTS TO A RATHER ACTIVE
PERIOD OF WEATHER FOR LATE MEMORIAL DAY WEEKEND INTO TUESDAY. THE
POTENTIAL EXISTS FOR ONE OR SEVERAL ROUNDS OF SHOWERS OR
THUNDERSTORMS DURING THIS PERIOD...ACCOMPANIED BY ABOVE-AVERAGE
TEMPERATURES AND RATHER HUMID WEATHER. CONVECTIVE SCENARIO WILL
DEPEND ON THUNDERSTORMS FROM PREVIOUS DAYS...SO IT IS DIFFICULT TO
PINPOINT SPECIFICS AT THIS TIME. IT APPEARS THAT MONDAY AND/OR
TUESDAY OFFER THE BEST POTENTIAL FOR THUNDER AS SHOWALTER INDICES
DROP BELOW ZERO (ESPECIALLY ON MONDAY) WITH RATHER STRONG UPPER-
LEVEL FLOW ALOFT. REGARDING TEMPERATURES...850MB TEMPERATURES
STEADILY RISE FROM 12-13 C ON SUNDAY TO AROUND 14-16 C ON
TUESDAY...LEADING TO HIGHS RISING FROM THE UPPER 70S TO THE
LOWER/MID 80S WITH LOWS IN THE UPPER 50S TO THE LOWER/MID 60S.
TEMPERATURES ON MONDAY APPEAR PARTICULARLY TRICKY EAST OF THE
GREENS GIVEN FORECAST COOLER THICKNESSES THERE...SO HAVE KEPT
HIGHS IN THE MID 70S IN THE NORTHEAST KINGDOM ON MONDAY.
COLD FRONT LOOKS TO SWEEP ACROSS THE NORTH COUNTRY LATER
TUESDAY...BRINGING WITH IT NOTICEABLY COOLER AND DRIER WEATHER TO
THE REGION FOR WEDNESDAY INTO THE REMAINDER OF THE EXTENDED.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THROUGH 18Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR
PERHAPS A THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME
INSTABILITY IN PLACE BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR
NOW. EXPECTING MAINLY VFR FOR TONIGHT THOUGH SOME 3SM BR WITH
ASSOCIATED MVFR/IFR CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT
WINDS TONIGHT THINK THAT THERE WILL BE ENOUGH TURBULENT MIXING TO
LIMIT FOG FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...LOCONTO
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
141 PM EDT THU MAY 24 2012
.SYNOPSIS...
A SOUTHERLY FLOW OF WARM AIR WILL CONTINUE INTO THE HOLIDAY
WEEKEND BRINGING AFTERNOON TEMPERATURES INTO THE 80S. AN UPPER
LEVEL AREA OF LOW PRESSURE MAY TRIGGER A FEW THUNDERSTORMS THIS
AFTERNOON..ESPECIALLY OVER THE POCONOS AND CATSKILLS. A WEAK FRONT
PASSING THROUGH THE AREA ON FRIDAY MAY TRIGGER MORE WIDESPREAD
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAKNESS IN THE UPR RDG TO THE EAST ALLOWS FOR SOME INCRSD
INSTABILITY OVER THE SRN AND ERN ZONES THIS AFTN. WILL CONT WITH
THE FCST OF A CHANCE OR SLGT CHANCE OF TRWS IN THOSE AREAS. NAM
HAS THE MOST CAPE...WITH BETTER THAN A THSND J/KG AT AVP LATE IN
THE DAY. RUC AND ARW SEEM A BIT MORE RSNBL WITH ARND HALF THAT OF
THE NAM. IN ANY CASE...THUNDER SHD BE ISLTD AND CHANCE OF SVR IS
QUITE SMALL WITH A VERY WEAK WIND FIELD ALOFT. DENSE FOG THIS
MRNG SHD ERODE QUICKLY WITH MIXING. MODELS GUID FOR HIGH TEMPS IN
GOOD AGREEMENT WITH AFTN MAXES FROM THE MID 70S TO LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
YET ANOTHER WEAK BNDRY BANGS INTO THE RDGG SFC AND ALOFT ON FRI.
NAM SHOWS SOME TALL AN SKINNY CAPE...ESP OVER THE NORTH ON FRI
AFTN. LACK OF LL MOISTURE SHD LIMIT CONV DVLPMT BUT WITH THE BNDRY
AND SOME WEAK HGT FALLS ALOFT...CHANCE POPS SEEM RSNBL FOR THE
AFTN...WITH THE BEST CHANCE OVER THE NY COUNTIES.
RDG BOUNCES BACK ON SAT WITH INCRSD HGTS AND WRMG ALOFT. THIS
SERVES TO STABILIZE THE SNDG LIMITING THE PSBLTY OF AFTN TRW. SFC
TEMPS BEGIN TO REBOUND AS WELL WITH TEMPS IN THE 80S ALL STATIONS
AND THE MAV GUID PUSHING AVP INTO THE UPR 80S.
ATTM THERE LOOKS TO BE LTL CHANCE OF SVR...AND WILL BE WELL BLO
AND HEAT ADVISORY THRESHOLD SO WILL REMOVE CAUTIONARY WRDG FROM
THE HWO AND JUST GO WITH A NIL STATEMENT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
UPDATED AS OF 130 PM...
NO BIG CHANGES TO THE LONG TERM FORECAST. BOTH THE EURO AND GFS
SHOW A FRONTAL BOUNDARY DRAPED OVER THE AREA SUNDAY NIGHT THROUGH
MONDAY NIGHT...WHICH WILL KEEP THE THREAT FOR SHOWERS AND STORMS
AROUND. JUST AS THE FORECASTER POINTED OUT YESTERDAY THOUGH...WE
ARE NOT EXPECTING A WASHOUT BUT WITH THE FRONT AROUND AND
INCREASING WARMTH AND HUMIDITY...STORMS CAN`T BE RULED OUT. TEMPS
WILL BE WELL INTO THE 80S MONDAY AND MAY APPROACH 90 ACROSS THE
FINGER LAKES WITH THE 850 TEMPS ON THE EURO (18C TO 20C) ARE
CORRECT. WITH TEMPS WELL INTO THE 80S TO NEAR 90...AND DEWPOINTS
APPROACHING THE LOWER 70S...HEAT INDICES MONDAY MAY BE IN THE
LOWER TO MIDDLE 90S.
THE BOUNDARY MENTIONED ABOVE WILL LIFT NORTH MONDAY NIGHT INTO
EARLY TUESDAY AND THIS WILL BRING US OUR BEST SHOT AT A LULL IN
ACTIVITY. EVENTUALLY HOWEVER TOWARD TUESDAY AFTERNOON A COLD FRONT
WILL APPROACH AND AGAIN SHOWERS AND STORMS WILL BE POSSIBLE.
COOLER AND DRIER AIR WILL BUILD IN FOR MID-WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
GENERALLY VFR IS EXPECTED THROUGH 0Z TONIGHT. ISOLATED TO
SCATTERED SHOWERS AND EVEN SOME RUMBLES OF THUNDER WILL IMPACT THE
SOUTHERN TERMINALS. WHILE THUNDERSTORMS ARE POSSIBLE...EVEN THOUGH
WE ARE SO CLOSE TO THE EVENT THE COVERAGE IS EXPECTED TO BE TOO
ISOLATED TO MENTION IN THE TAFS. MOIST SOUTHEAST FLOW WILL BRING
MORE RESTRICTIONS LATE TONIGHT ESPECIALLY ACROSS NE PA AND
SOUTHERN TIER OF NEW YORK. FOR NOW WENT MVFR AFTER 06Z EVERYWHERE
EXCEPT KSYR WHERE CONFIDENCE IS LOWER.
ON FRIDAY MVFR CIGS WILL IMPROVE TO VFR BETWEEN 15Z AND 18Z.
WINDS SOUTHEAST 10 TO 20 TODAY...BECOMING LIGHT SOUTHEAST TONIGHT.
SOUTHEAST WINDS FRIDAY BECOMING SOUTHWEST 10 TO 20 WITH GUSTS TO
25 MPH.
.OUTLOOK...
FRIDAY AFTERNOON...MVFR POSSIBLE IN SCATTERED MAINLY AFTERNOON SHOWERS AND
THUNDERSTORMS.
FRIDAY NIGHT THRU SUN...GENERALLY VFR.
MONDAY/TUESDAY...MVFR POSSIBLE IN SCATTERED SHOWERS AND THUNDERSTORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM
SHORT TERM...DGM
LONG TERM...HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
121 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 114 PM EDT THURSDAY...NO SIGNIFICANT CHANGES TO CRNT FCST
WITH TEMPS WARMING INTO THE M70S SOUTHERN VT TO M80S IN THE SLV.
THIS SFC HEATING HAS CREATED CAPE VALUES BTWN 1200 AND 1600
J/KG...BUT WATER VAPOR SHOWS BUILDING RIDGE AND STRONG AREA OF
SUBSIDENCE ACRS OUR CWA. THIS WL RESULT IN LIMITED AREAL COVERAGE
OF CONVECTION THIS AFTN...WITH BEST CHC ALONG THE SPINE OF THE
GREEN MTNS AND ACRS PARTS OF NORTHERN NY. WL CONT TO MENTION SCHC
TO CHC POPS ACRS THESE REGIONS.
FCST IN GREAT SHAPE THIS MORNING WITH ONLY MINOR CHANGES NEEDED.
VIS SATL PIC SHOWS LOW CLOUDS SLOWLY DISSIPATING ACRS
EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT AS SFC HEATING
CONTS THESE CLOUDS WL DEVELOP INTO A SCATTERED/BROKEN
CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV 4KM SHOWS SOME
INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM INTO THE U70S
TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI VALUES NEAR
-3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF SUBSIDENCE AND
ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER LVL RIDGE ACRS
OUR REGION. THIS WL LIMIT AREAL COVERAGE OF CONVECTION THIS
AFTN...THINKING JUST A SCHC DACKS/SLV AND CENTRAL/EASTERN VT
ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST OF CWA WL BE
RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO L80S CPV TO M/U
70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 521 AM EDT THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER
THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT...WITH FAIR AND DRY
WEATHER EXPECTED. A FRONTAL SYSTEM JUST SOUTH OF THE REGION SUNDAY
NIGHT WILL BEGIN TO MOVE SLOWLY NORTHEAST AS A WARM FRONT ON
MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
REGION MONDAY AFTERNOON AND CONTINUING INTO MONDAY NIGHT AND
TUESDAY. A COLD FRONT WILL THEN MOVE THROUGH THE REGION TUESDAY
NIGHT WITH A CHANCE FOR SOME MORE SHOWERS AND THUNDERSTORMS.
EXPECTING COOLER TEMPERATURES ALONG WITH CLOUD COVER LINGERING
ACROSS THE REGION ON WEDNESDAY...SO HAVE KEPT IN SLIGHT CHANCE
POPS FOR SHOWERS ON WEDNESDAY. TEMPERATURE FORECAST FOR MONDAY AND
TUESDAY COULD BE A BIT TRICKY AND WILL DEPEND ON WHERE THIS SLOW
MOVING WARM FRONT WILL BE ACROSS THE REGION ON THESE DAYS. HAVE
LEANED TOWARD ENSEMBLE MOS MEANS FOR MAX AND MIN TEMPERATURES ON
MONDAY AND TUESDAY.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
THROUGH 18Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR
PERHAPS A THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME
INSTABILITY IN PLACE BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR
NOW. EXPECTING MAINLY VFR FOR TONIGHT THOUGH SOME 3SM BR WITH
ASSOCIATED MVFR/IFR CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT
WINDS TONIGHT THINK THAT THERE WILL BE ENOUGH TURBULENT MIXING TO
LIMIT FOG FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...WGH
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
111 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1010 AM EDT THURSDAY...FCST IN GREAT SHAPE THIS MORNING WITH
ONLY MINOR CHANGES NEEDED. VIS SATL PIC SHOWS LOW CLOUDS SLOWLY
DISSIPATING ACRS EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT
AS SFC HEATING CONTS THESE CLOUDS WL DEVELOP INTO A
SCATTERED/BROKEN CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV
4KM SHOWS SOME INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM
INTO THE U70S TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI
VALUES NEAR -3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF
SUBSIDENCE AND ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER
LVL RIDGE ACRS OUR REGION. THIS WL LIMIT AREAL COVERAGE OF
CONVECTION THIS AFTN...THINKING JUST A SCHC DACKS/SLV AND
CENTRAL/EASTERN VT ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST
OF CWA WL BE RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO
L80S CPV TO M/U 70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 521 AM EDT THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER
THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT...WITH FAIR AND DRY
WEATHER EXPECTED. A FRONTAL SYSTEM JUST SOUTH OF THE REGION SUNDAY
NIGHT WILL BEGIN TO MOVE SLOWLY NORTHEAST AS A WARM FRONT ON
MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
REGION MONDAY AFTERNOON AND CONTINUING INTO MONDAY NIGHT AND
TUESDAY. A COLD FRONT WILL THEN MOVE THROUGH THE REGION TUESDAY
NIGHT WITH A CHANCE FOR SOME MORE SHOWERS AND THUNDERSTORMS.
EXPECTING COOLER TEMPERATURES ALONG WITH CLOUD COVER LINGERING
ACROSS THE REGION ON WEDNESDAY...SO HAVE KEPT IN SLIGHT CHANCE
POPS FOR SHOWERS ON WEDNESDAY. TEMPERATURE FORECAST FOR MONDAY AND
TUESDAY COULD BE A BIT TRICKY AND WILL DEPEND ON WHERE THIS SLOW
MOVING WARM FRONT WILL BE ACROSS THE REGION ON THESE DAYS. HAVE
LEANED TOWARD ENSEMBLE MOS MEANS FOR MAX AND MIN TEMPERATURES ON
MONDAY AND TUESDAY.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
THROUGH 18Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR
PERHAPS A THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME
INSTABILITY IN PLACE BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR
NOW. EXPECTING MAINLY VFR FOR TONIGHT THOUGH SOME 3SM BR WITH
ASSOCIATED MVFR/IFR CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT
WINDS TONIGHT THINK THAT THERE WILL BE ENOUGH TURBULENT MIXING TO
LIMIT FOG FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...WGH
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
110 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1010 AM EDT THURSDAY...FCST IN GREAT SHAPE THIS MORNING WITH
ONLY MINOR CHANGES NEEDED. VIS SATL PIC SHOWS LOW CLOUDS SLOWLY
DISSIPATING ACRS EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT
AS SFC HEATING CONTS THESE CLOUDS WL DEVELOP INTO A
SCATTERED/BROKEN CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV
4KM SHOWS SOME INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM
INTO THE U70S TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI
VALUES NEAR -3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF
SUBSIDENCE AND ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER
LVL RIDGE ACRS OUR REGION. THIS WL LIMIT AREAL COVERAGE OF
CONVECTION THIS AFTN...THINKING JUST A SCHC DACKS/SLV AND
CENTRAL/EASTERN VT ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST
OF CWA WL BE RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO
L80S CPV TO M/U 70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 521 AM EDT THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER
THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT...WITH FAIR AND DRY
WEATHER EXPECTED. A FRONTAL SYSTEM JUST SOUTH OF THE REGION SUNDAY
NIGHT WILL BEGIN TO MOVE SLOWLY NORTHEAST AS A WARM FRONT ON
MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
REGION MONDAY AFTERNOON AND CONTINUING INTO MONDAY NIGHT AND
TUESDAY. A COLD FRONT WILL THEN MOVE THROUGH THE REGION TUESDAY
NIGHT WITH A CHANCE FOR SOME MORE SHOWERS AND THUNDERSTORMS.
EXPECTING COOLER TEMPERATURES ALONG WITH CLOUD COVER LINGERING
ACROSS THE REGION ON WEDNESDAY...SO HAVE KEPT IN SLIGHT CHANCE
POPS FOR SHOWERS ON WEDNESDAY. TEMPERATURE FORECAST FOR MONDAY AND
TUESDAY COULD BE A BIT TRICKY AND WILL DEPEND ON WHERE THIS SLOW
MOVING WARM FRONT WILL BE ACROSS THE REGION ON THESE DAYS. HAVE
LEANED TOWARD ENSEMBLE MOS MEANS FOR MAX AND MIN TEMPERATURES ON
MONDAY AND TUESDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
THROUGH 12Z FRIDAY...MOIST SOUTHEAST FLOW ALONG AND EAST OF THE
GREENS BROUGHT SOME LOWER MVFR CEILINGS AT MPV THIS
MORNING...THOUGH THESE HAVE BEGUN TO LIFT BY EARLY AFTERNOON.
CURRENT SKIES RANGE FROM BKN/OVC VFR ACROSS MPV TO FEW/SCT VFR FOR
THE REMAINDER OF THE TERMINALS. AFTERNOON MIXING IN THE PARTLY
CLOUDY SKIES HAS RESULTED IN SOUTHERLY GUSTS TO AROUND 20KTS THIS
AFTERNOON...AND THESE WILL CONTINUE THROUGH 23Z/00Z BEFORE
BOUNDARY LAYER STABILIZES. THERE COULD BE A STRAY SHOWER OR PERHAPS A
THUNDERSHOWER AT RUT THIS AFTERNOON WITH SOME INSTABILITY IN PLACE
BUT NOT MUCH OF A TRIGGER...SO LEFT OUT FOR NOW. EXPECTING MAINLY
VFR FOR TONIGHT THOUGH SOME 3SM BR WITH ASSOCIATED MVFR/IFR
CEILINGS AT MPV AND SLK. DESPITE FAIRLY LIGHT WINDS TONIGHT THINK
THAT THERE WILL BE ENOUGH TURBULENT MIXING TO LIMIT FOG
FORMATION...THOUGH MIST LOOKS POSSIBLE.
ANY LINGERING LOWER CEILINGS LIFT BY 12-14Z FRIDAY BRINGING VFR
CEILINGS AND AFTERNOON SOUTHERLY GUSTS TO AROUND 20KTS. SURFACE
TROUGH WILL APPROACH FROM THE WEST LATE IN THE TAF PERIOD...WHICH
MAY TRIGGER SOME SHOWERS OR THUNDERSTORMS. THIS WILL BE
MONITORED...THOUGH FEEL AT THIS TIME THAT ANY SHOWERS/STORMS WILL
HOLD OFF UNTIL AFTER 18Z FRIDAY.
OUTLOOK 18Z FRIDAY THROUGH MONDAY...
18Z FRIDAY - 06Z SATURDAY...VFR WITH PERIODS MVFR/IFR IN SCATTERED
SHOWERS/STORMS AS COLD FRONT TRAVERSES THE REGION.
06Z SATURDAY - 12Z SUNDAY...VFR UNDER HIGH PRESSURE. POSSIBLE
EVENING FOG/MIST AT MPV/SLK WITH IFR CEILINGS/VISIBILITIES.
12Z SUNDAY - 12Z MONDAY...VFR DEGRADING TO MVFR IN
SHOWERS/POSSIBLE THUNDER LATER SUNDAY/SUNDAY NIGHT AS WARM FRONT
MOVES NORTHWARD.
12Z MONDAY - 00Z TUESDAY...MAINLY VFR THOUGH CAN`T RULE OUT A
SHOWER OR THUNDERSTORM MONDAY AFTERNOON.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...WGH
AVIATION...LOCONTO
MARINE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1209 PM EDT THU MAY 24 2012
.SYNOPSIS...
DEPARTING HIGH PRESSURE WILL BRING SOUTHERLY FLOW AND A CHANCE
FOR UPSLOPE RAIN SHOWERS...MAINLY OVER THE HIGH TERRAIN TODAY. A
BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL ARRIVE
LATE FRIDAY INTO FRIDAY NIGHT ASSOCIATED WITH A SURFACE COLD
FRONT. SLIGHTLY COOLER AND DRIER CONDITIONS WILL PREVAIL FOR THE
UPCOMING HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1010 AM EDT THURSDAY...FCST IN GREAT SHAPE THIS MORNING WITH
ONLY MINOR CHANGES NEEDED. VIS SATL PIC SHOWS LOW CLOUDS SLOWLY
DISSIPATING ACRS EASTERN/CENTRAL VT AND PARTS OF THE DACKS. EXPECT
AS SFC HEATING CONTS THESE CLOUDS WL DEVELOP INTO A
SCATTERED/BROKEN CUMULUS/TOWERING CUMULUS DECK. RAP AND LOCAL BTV
4KM SHOWS SOME INSTABILITY DEVELOPING THIS AFTN AS SFC TEMPS WARM
INTO THE U70S TO M80S...WITH CAPE VALUES AROUND 1000 J/KG AND LI
VALUES NEAR -3C. HOWEVER...WATER VAPOR SHOWS LARGE AREA OF
SUBSIDENCE AND ASSOCIATED DEEP DRY LAYER WITH BUILDING MID/UPPER
LVL RIDGE ACRS OUR REGION. THIS WL LIMIT AREAL COVERAGE OF
CONVECTION THIS AFTN...THINKING JUST A SCHC DACKS/SLV AND
CENTRAL/EASTERN VT ZNS...WITH LOW CHC POPS NEAR KILLINGTON. MOST
OF CWA WL BE RAINFREE THIS AFTN...WITH TEMPS IN THE M80S SLV TO
L80S CPV TO M/U 70S MTNS.
PREVIOUS DISCUSSION FOLLOWS...FOG WILL DISSIPATE THIS MORNING
WITH CLOUDS MOVING IN FROM THE SOUTH EAST AS DEPARTING HIGH
PRESSURE BRINGS SOUTHERLY TO SOUTHEASTERLY FLOW OVER THE REGION.
THIS WILL ALLOW MOISTURE FROM YESTERDAYS FRONT TO SURGE NORTHWARD.
A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE FORECAST AREA
TODAY. THIS FEATURE COMBINED WITH SOUTHEASTERLY UPSLOPE FLOW WILL
BE ENOUGH CONVERGENCE TO DEVELOP FEW TO SCATTERED SHOWERS AND
SLIGHT CHANCE FOR THUNDERSTORMS OVER THE HIGHER TERRAIN. BEST CHC
FOR SHOWERS/STORMS WILL BE ACROSS EASTERN/CENTRAL VT GREEN MTNS
AND HIGHER TERRAIN OF THE ADIRONDACKS. NAM AND GFS INDICATE AREAS
OF OVER 1000J/KG THIS AFTERNOON. LACK OF SHEAR WILL KEEP ANY
CONVECTIVE ACTIVITY SUB-SEVERE.
WINDS MAINLY OUT OF THE SOUTH WILL CHANNEL UP THE CHAMPLAIN
VALLEY...WITH SPEEDS OF 15-25 KTS OVER LAKE CHAMPLAIN AND OVER THE
MTNS DURING THE DAY.
850HPA TEMPERATURES WILL WARM INTO THE MID TEENS OVER SOUTHERN VT
AND UPPER TEENS IN NORTHERN NY. INCREASING CLOUDS WILL KEEP SFC
TEMPS FROM REACHING FULL HEATING POTENTIAL OVER MOST OF VT. MAX
TEMPS IN THE UPPER 70S TO AROUND 80 IN THE VALLEYS AND MID 60S TO
LOW 70S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 455 AM EDT THURSDAY...AS THE SUN SETS...INSTABILITY AND
THEREFORE SHOWERS WILL DISSIPATE THIS EVENING. CLOUDS WILL
CONTINUE TO INCREASE AS MOISTURE CONTINUES TO FILTER IN FROM THE
SOUTHERLY FLOW. OVERNIGHT MIN TEMPS WILL BE IN THE LOW 60S IN THE
VALLEYS AND REACHING THE MID 40S IN THE HIGHER TERRAIN.
A COLD FRONT WILL APPROACH FROM THE GREAT LAKES REGION ON FRIDAY.
GFS SLIGHTLY FASTER SOLUTION WITH BEST DEFORMATION OVER WESTERN
NY BY 18Z. NAM A FEW HOURS SLOWER...BUT BOTH MODELS SHOW
DEFORMATION WASHING OUT OVER EASTERN NY/SOUTHERN VT FRIDAY
EVENING INTO SATURDAY MORNING. THIS COLD FRONT WILL BE
ACCOMPANIED BY A MID LEVEL JET ENTRANCE REGION AT 850MB AND 700MB
IN SOUTHEASTERN ONTARIO STRETCHING NORTHEAST INTO QUEBEC. CAN
EXPECT SHOWERS AND THUNDERSTORMS TO AHEAD AND ACCOMPANYING THE
COLD FRONT AS SOUTHERLY FLOW AHEAD OF THE FRONT CONTINUES TO
BRING WARM MOIST AIR INTO THE REGION...AS NOTED BY SFC DEWPOINTS
IN THE 60S. AS AN UPPER LEVEL TROF APPROACHES THE
NORTHEAST...WIND SHEAR WILL INCREASE WITH BEST VALUES BETWEEN
25-30 KNOTS OF 0-3KM SHEAR AND 30-35 KTS OF 0-6 KM SHEAR. THIS
MODEST SHEAR COMBINED WITH CAPE VALUES BETWEEN 1000 AND 2000 J/KG
SUPPORT SCATTERED CONVECTION ALONG THE BOUNDARY WITH A FEW
STRONGER STORMS. NOT ANTICIPATING A WIDESPREAD SEVERE WEATHER
EVENT...BUT A FEW STRONGER STORMS WITH GUSTY WINDS AND DIME SIZE
HAIL WILL BE POSSIBLE. SHOWERS AND THUNDERSTORM WILL CONTINUE INTO
FRIDAY EVENING BEFORE THE FRONT MOVES THROUGH THE EASTERN EDGE OF
THE FORECAST AREA AFTER MIDNIGHT.
SATURDAY WILL SEE DRIER CONDITIONS BEHIND THE FRONT AS HIGH
PRESSURE BUILDS IN OVER EASTERN ONTARIO/WESTERN QUEBEC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 521 AM EDT THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER
THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT...WITH FAIR AND DRY
WEATHER EXPECTED. A FRONTAL SYSTEM JUST SOUTH OF THE REGION SUNDAY
NIGHT WILL BEGIN TO MOVE SLOWLY NORTHEAST AS A WARM FRONT ON
MONDAY. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
REGION MONDAY AFTERNOON AND CONTINUING INTO MONDAY NIGHT AND
TUESDAY. A COLD FRONT WILL THEN MOVE THROUGH THE REGION TUESDAY
NIGHT WITH A CHANCE FOR SOME MORE SHOWERS AND THUNDERSTORMS.
EXPECTING COOLER TEMPERATURES ALONG WITH CLOUD COVER LINGERING
ACROSS THE REGION ON WEDNESDAY...SO HAVE KEPT IN SLIGHT CHANCE
POPS FOR SHOWERS ON WEDNESDAY. TEMPERATURE FORECAST FOR MONDAY AND
TUESDAY COULD BE A BIT TRICKY AND WILL DEPEND ON WHERE THIS SLOW
MOVING WARM FRONT WILL BE ACROSS THE REGION ON THESE DAYS. HAVE
LEANED TOWARD ENSEMBLE MOS MEANS FOR MAX AND MIN TEMPERATURES ON
MONDAY AND TUESDAY.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THROUGH 12Z FRIDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE
PERIOD...EXCEPT FOR SOME AREAS OF MVFR/IFR IN FOG AND MIST EARLY
THIS MORNING. EXPECTING AND FOG OR MIST WILL BURN OFF BY 14Z
THURSDAY. VISIBLE SATELLITE LOOP SHOWING LOW STRATUS CLOUDS ACROSS
EASTERN VERMONT AS OF 1130Z THURSDAY. THESE LOWER CEILINGS MAY NOT
LIFT UNTIL 16-17Z THURSDAY. GUIDANCE SHOWING SOME STEEP LOW LEVEL
LAPSE RATES TO DEVELOP ACROSS THE REGION TODAY...SO THERE COULD BE
SOME ISOLATED SHOWERS AND A POSSIBLE THUNDERSTORMS THIS AFTERNOON.
HAVE NOT INCLUDED ANY MENTION IN THE TAFS AT THIS TIME...DUE TO
LOCALIZED NATURE OF THIS. SURFACE PRESSURE GRADIENT TO TIGHTEN
ACROSS THE REGION TODAY...WITH SURFACE WINDGUSTS OF AROUND 20
KNOTS OR GREATER POSSIBLE BETWEEN 14Z-17Z THURSDAY AND CONTINUING
UNTIL 00Z FRIDAY. EXPECTING SURFACE WINDS TO DIMINISH TO LESS THAN
10 KNOTS AFTER 00Z FRIDAY. EXPECTING SOME MORE AREAS OF IFR/MVFR
CEILINGS IN FOG AND MIST...MAINLY AFTER 04Z FRIDAY...ESPECIALLY
ACROSS EASTERN VERMONT.
OUTLOOK 06Z FRIDAY THROUGH MONDAY...
06Z FRIDAY THROUGH 18Z FRIDAY...GENERALLY VFR UNDER RIDGE OF HIGH
PRESSURE...WITH MORNING FOG/BR POSSIBLE. 18Z FRIDAY THROUGH
18Z MONDAY...GENERALLY VFR. 18Z MONDAY THROUGH 00Z TUESDAY CHANCES
FOR MVFR IN SCATTERED SHOWERS/TSTORMS AS A WARM FRONT LIFTS SLOWLY
NORTHEAST ACROSS THE REGION.
&&
.MARINE...
A LAKE WIND ADVISORY IS NOW IN EFFECT THIS AFTERNOON INTO TONIGHT
FOR LAKE CHAMPLAIN. SOUTH WINDS AT COLCHESTER REEF LATE THIS
MORNING HAVE INCREASED TO NEAR 20 KNOTS...AND LOCAL BTV WRF MODELS
SHOW SOUTHERLY FLOW INCREASING TO AROUND 25 KNOTS THIS AFTERNOON.
EXPECT SOUTH WINDS TO BE IN THE 15 TO 25 KNOT RANGE WITH 2 FOOT
WAVES ACROSS THE BROAD LAKE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KGM/TABER
NEAR TERM...KGM/TABER
SHORT TERM...KGM
LONG TERM...WGH
AVIATION...WGH
MARINE...LOCONTO