Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/01/12
AREA FORECAST DISCUSSION
NWS NEW YORK NY
240 PM EDT WED MAY 30 2012
.SYNOPSIS...
A COLD FRONT APPROACHING FROM THE WEST WILL SLOWLY MOVE ACROSS
TONIGHT. HIGH PRESSURE WILL BUILD OVER THE AREA ON THURSDAY...
THEN DEPART ON FRIDAY. LOW PRESSURE WILL IMPACT THE REGION THIS
WEEKEND AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SFC TROUGH WILL BE EAST OF LONG ISLAND THE REMAINDER OF THIS
AFTERNOON WITH THE MID AND UPPER LEVEL TROUGH CONTINUING TO
APPROACH. IN ADDITION...THERE IS 30-40 KT OF BULK SHEAR BETWEEN
0-6KM ALONG WITH MARGINAL SFC CAPE OF A FEW HUNDRED J/KG FOR
COASTAL SECTIONS AND AROUND 700 TO 1000 J/KG FOR WESTERN
LOCATIONS. LAYER PW VALUES ARE ON A DOWNWARD TREND BUT WILL STILL
BE MOSTLY ABOVE 1 INCH.
WITH SW FLOW ALOFT...CLOUDS HAVE BEEN STREAMING IN FROM LOW
PRESSURE NEAR THE CAROLINAS. DAYTIME HEATING HAS THEREBY BEEN
MITIGATED AND MAX TEMPS WERE LOWERED BY A FEW DEGREES. ISOLATED
SHOWERS/SPRINKLES FOR THE LONG ISLAND AREA EXPECTED FOR THE REST
OF THE AFTERNOON WITH AN INCREASING CHANCE OF SHOWERS AND
THUNDERSTORMS BY THE LOWER HUDSON VALLEY BY LATE THIS
AFTERNOON...AHEAD OF THE COLD FRONT.
SHOWERS AND THUNDERSTORMS EXPECTED TO START OUT ISOLATED AND GROW
TO SCATTERED IN COVERAGE TOWARDS EARLY EVENING FOR WESTERN
SECTIONS OF THE FORECAST AREA. FOR EASTERN AREAS...SCATTERED
SHOWERS WILL DIMINISH IN COVERAGE LEAVING SOME SPRINKLES WITH MOST
SHOWER ACTIVITY PUSHING FARTHER OFFSHORE. THE HRRR SHOWS A SIMILAR
DEPICTION IN ITS REFLECTIVITY FIELDS. CONVECTION OVERALL WILL BE
LOW TOPPED FROM 20-30KFT. GUSTY WINDS WILL BE POSSIBLE WITH SOME
THUNDERSTORMS ESPECIALLY TOWARDS LOWER HUDSON VALLEY WITH MID
LEVEL DRYING AND HIGHER DCAPE VALUES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
COLD FRONT WILL SLOWLY MOVE ACROSS THE AREA LATE TONIGHT BUT
WEAKENS WITH ITS EASTWARD MOVEMENT. THE UPPER LEVEL TROUGH
FLATTENS OUT LEAVING MORE OF A WNW FLOW. WITHOUT INSTABILITY AND
WITHOUT MUCH SYNOPTIC FORCING...SHOWERS WILL LOWER IN COVERAGE BY
LATER THIS EVENING FROM WEST TO EAST. MUCAPE DECREASES A LOT AFTER
00Z SO JUST LEFT A SLIGHT CHANCE OF THUNDERSTORMS.
DRYING CONDITIONS EVENTUALLY COME INTO PLACE LATE TONIGHT BEHIND
THE FRONT. DEWPOINTS DO NOT LOWER SIGNIFICANTLY BEHIND IT AND
WITH THE LIGHT WINDS AND ESPECIALLY WITH ANY LEFTOVER
MOISTURE...PATCHY FOG CAN BE EXPECTED AS TEMPS COOL BETTER WITH
SOME DECREASE IN CLOUDS.
A MAV/MET/NAM 12 SFC TEMP BLEND WAS USED FOR LOWS WHICH MORE ON
THE WARMER SIDE GIVEN THE ABUNDANT CLOUDS AND LIGHT ONSHORE FLOW
EXPECTED FOR THE FIRST HALF OF THE NIGHT.
MEANWHILE...BERYL IS FORECAST TO TRACK NE FROM THE CAROLINA COAST
PASSING WELL SE OF THE AREA ON THU. REFER TO THE NATIONAL
HURRICANE CENTER FOR THE OFFICIAL TRACK AND INTENSITY FORECASTS.
ONLY POTENTIAL IMPACTS FROM BERYL WILL BE MARINE RELATED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE PERIOD BEGINS FAIRLY QUIET WITH THE REMNANTS TROPICAL CYCLONE
BERYL PASSING WELL TO THE SOUTH AND EAST AND HIGH PRESSURE BUILDING
OVER THE NORTHEAST. PLEASE REFER TO THE NATIONAL HURRICANE CENTER
FOR THE OFFICIAL TRACK AND INTENSITY FORECASTS FOR BERYL. WITH UPPER
LEVEL RIDGING AND SUBSIDENCE BUILDING IN...EXPECT MOSTLY CLEAR SKIES
THURS NIGHT INTO FRI MORNING. AS THE HIGH PUSHES IN..EXPECT WINDS TO
SHIFT FROM A NORTHWESTERLY FLOW...BACK TO AN ONSHORE FLOW...WHICH
WILL AID IN INCREASING THE MOISTURE FIELD AND IN TURN INCREASE CLOUD
COVERAGE FRIDAY. THIS WILL HELP KEEP TEMPS NEAR NORMAL DESPITE 925MB
TEMPS REACHING INTO THE UPPER TEENS.
NOW FOR THE WEEKEND...SEEMS THE MODELS CONTINUE TO SPEED UP THE
PASSAGE OF THE COLD FRONT...WITH THERE BEING GOOD AGREEMENT IN THE
PASSAGE ON SAT. THE WARM FRONT PUSHES THROUGH OVERNIGHT FRI...WITH
THE LOW OVER SOUTHERN CANADA OCCLUDING...THEN DRAGGING THE FRONT
THROUGH. HAVE ADJUSTED POPS TO REFLECT THE LATEST PASSAGE OF THE
FRONT...BRINGING IN CHC FOR THE WESTERN AREAS ON FRIDAY...THEN
SPREADING LIKELY ACROSS THE AREA OVERNIGHT FRI INTO SAT...THEN
DIMINISHING DOWN SAT NIGHT. THE SOUTHERLY FLOW AHEAD OF THE
APPROACHING FRONT INJECTS IN PLENTY OF MOISTURE...WITH PW VALUES
BETWEEN 1.5 AND 2.0 INCHES. VERY LITTLE INSTABILITY IS NOTED HOWEVER
SO HAVE SIDED WITH KEEPING JUST RAIN SHOWERS WITH NO MENTION OF
THUNDER...THOUGH ANY DEVELOPING SHOWERS COULD BE HEAVY AT TIMES
RIGHT AHEAD OF THE FRONT.
THE UPPER LEVEL CLOSED LOW FINALLY PUSHES EAST INTO SE CANADA ON
SUN...BRINGING A VORT MAX RIGHT THROUGH THE REGION SUN AFTN.
THIS...COMBINED WITH A SURFACE TROUGH PASSAGE BETWEEN 18Z AND 00Z
MAY LEAD TO POSSIBLE DEVELOPMENT OF SOME AFTN ISOLATED SHOWERS AND
THUNDERSTORMS WITH SOUNDINGS HINTING AT CAPE VALUES BETWEEN 500 AND
1000 J/KG. THE ORIGINAL SURFACE LOW THEN PUSHES TO THE EAST AND
SETTLES OFFSHORE OF MAINE FOR THE FIRST PART OF THE WEEK WHILE THE
UPPER LEVEL LOW REMAINS NEARLY STATIONARY AND BUILDS ACROSS THE
NORTHEAST. THE 00Z GFS KEEPS THE DEVELOPMENT OF A SURFACE LOW OFF
THE CAROLINAS WHILE THE 00Z ECMWF SHOWS NO DEVELOPMENT YET DEEPENS
THE LOW OFF THE NORTHEAST MORE. WITH THE MODEL DISCREPANCY...SIDED
MOSTLY WITH THE PREVIOUS FORECAST FOR MON INTO WED...KEEPING SLIGHT
CHC POPS AND THE MENTION OF THUNDER FOR THE AFTN HOURS UNDER THE
PERSISTING UPPER LEVEL LOW AND SURFACE LOW TO THE NORTHEAST.
TEMPS WILL FLUCTUATE SLIGHTLY THIS WEEKEND...WITH SLIGHTLY COOLER
AIR MOVING IN BEHIND THE FRONT FOR SAT AND SUN. HOWEVER...TEMPS
REBOUND TO NEAR NORMAL FOR HIGHS AND SLIGHTLY ABOVE NORMAL FOR LOWS
FOR THE START OF THE WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A WEAK COLD FRONT WILL APPROACH FROM THE WEST THIS AFTERNOON AND
PASS THROUGH TONIGHT...FOLLOWED BY WEAK HIGH PRESSURE ON THU.
BKN-OVC MID LEVEL DECK MAKING STEADY EASTWARD PROGRESS...AND
SHOULD BE EAST OF THE NYC METRO TERMINALS BY 20Z-22Z.
COLD FRONT WAS ENTERING CENTRAL NY STATE AND PA. EXPECT SCT
SHOWERS AND A FEW TSTMS TO DEVELOP AHEAD OF THE FRONT...AND IMPACT
MAINLY KSWF IN TWO ROUNDS...ONE LATE THIS AFTERNOON AND ANOTHER
THIS EVENING JUST BEFORE FROPA. UNCERTAIN HOW MUCH NYC METRO WILL
BE IMPACTED BY THIS ACTIVITY...KEPT EARLIER MENTION OF BRIEF MVFR
FOR KEWR/KTEB AND BACKED OFF A LITTLE FOR KLGA/KJFK WITH MENTION
OF VCSH ONLY.
CANNOT RULE OUT A BRIEF SHOWER OR ISOLD TSTM JUST BEFORE
FROPA LATER TONIGHT...ESPECIALLY FROM NYC METRO NORTH/WEST...BUT
CONFIDENCE/COVERAGE TOO LOW TO MENTION IN TAF.
KGON LIKELY TO SEE IFR CONDS IN AND/OR LOW CLOUDS TONIGHT BEFORE
FROPA. KISP ALSO LIKELY TO SEE MVFR CONDS...CANNOT RULE OUT
BRIEF IFR.
S-SW FLOW 10 KT OR LESS THIS AFTERNOON SHOULD VEER MORE SW AND
LIGHTEN THIS EVENING...THEN SHIFT N AFTER FROPA. SPEEDS AROUND 10
KT WITH OCNL GUSTS 15 KT POSSIBLE AT THE NYC METROS THU MORNING.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER THIS EVENING...
CONFIDENCE/COVERAGE STILL TOO LOW FOR TAF MENTION.
KLGA FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER THIS EVENING...
CONFIDENCE/COVERAGE STILL TOO LOW FOR TAF MENTION.
KEWR FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER THIS EVENING...
CONFIDENCE/COVERAGE STILL TOO LOW FOR TAF MENTION.
KTEB FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER THIS EVENING...
CONFIDENCE/COVERAGE STILL TOO LOW FOR TAF MENTION.
KHPN FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER THIS EVENING...
CONFIDENCE/COVERAGE TOO LOW FOR TAF MENTION.
KISP FCSTER COMMENTS: LOW CHANCE OF IFR CONDITIONS BETWEEN
04Z-07Z TONIGHT.
.OUTLOOK FOR 18Z THU THROUGH SUNDAY...
.THU AFTERNOON-FRI...VFR.
.FRI NIGHT...IFR POSSIBLE IN RAIN...HEAVY AT TIMES WITH CHANCE OF
THUNDER AS A STRONG COLD FRONT AND WAVE OF LOW PRESSURE MOVE
ACROSS.
.SAT...MVFR OR LOWER IN SHOWERS...ESPECIALLY IN THE MORNING.
CONDS IMPROVING FROM WEST-EAST IN THE LATE MORNING AND AFTERNOON.
.SAT NIGHT-SUN MORNING...VFR.
.SUN...MOSTLY VFR. ONLY SLIGHT CHANCE OF AN AFTERNOON/EVENING
SHOWER OR TSTM.
.MON...MOSTLY VFR. BRIEF MVFR POSSIBLE IN SCT SHOWERS.
&&
.MARINE...
SUB-ADVY CONDS EXPECTED THROUGH THU. WW3 APPEARS TO BE RUNNING
1-2 FT HIGH THROUGH THU AND HAVE ADJUSTED. NEITHER WNA OR NAH
GUIDANCE IS INDICATING SWELLS FROM BERYL UNTIL FRIDAY NIGHT/SAT
RESPECTIVELY...BUT MAY SEE THEM AS EARLY AS THU NIGHT.
WINDS SHOULD REMAIN BELOW SCA CRITERIA INTO THIS WEEKEND. SEAS
HOWEVER...WILL BUILD TO AROUND 5 TO 6 FT ON THE OCEAN WATERS WITH A
COMBINATION OF A PERSISTENT FLOW AND SWELLS FROM THE PASSAGE OF
BERYL TO THE SOUTH AND EAST. THE SEAS WILL REMAIN ELEVATED INTO THE
WEEKEND...WITH THE WINDS INCREASING AHEAD OF THE COLD
FRONT...POSSIBLY TO MARGINAL SCA CONDITIONS.
SEAS AND WINDS DIMINISH IN THE WAKE OF THE COLD FRONT...WITH SUB SCA
CONDITIONS EXPECTED THE END OF THE WEEKEND AND INTO NEXT WEEK.
&&
.HYDROLOGY...
WIDESPREAD SIGNIFICANT RAINFALL IS NOT EXPECTED TODAY.
HOWEVER...PRECIPITABLE WATERS FORECAST NEAR 1.5 INCHES COULD
PRODUCE LOCALLY HEAVY DOWNPOURS IN ANY CONVECTION.
THE NEXT CHANCE FOR SIGNIFICANT RAINFALL WILL BE FRIDAY NIGHT INTO
SATURDAY. 1/2 TO 1 INCH OF BASIN AVERAGE QPF IS EXPECTED AT THIS
TIME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...JM
SHORT TERM...
LONG TERM...
AVIATION...GOODMAN
MARINE...
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1113 AM EDT WED MAY 30 2012
.SYNOPSIS...
A COLD FRONT APPROACHING FROM THE WEST WILL SLOWLY MOVE ACROSS
TONIGHT. HIGH PRESSURE WILL BUILD OVER THE AREA ON THURSDAY...
THEN DEPART ON FRIDAY. LOW PRESSURE WILL IMPACT THE REGION THIS
WEEKEND AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SFC TROUGH WILL MOVING ACROSS LONG ISLAND THIS AFTERNOON AND THE
MID AND UPPER LEVEL TROUGH WILL CONTINUE TO APPROACH. IN
ADDITION...THERE IS 30-40 KT OF BULK SHEAR BETWEEN 0-6KM ALONG WITH
MARGINAL SFC CAPE OF A FEW HUNDRED J/KG FOR COASTAL SECTIONS AND
AROUND 700 TO 1000 J/KG FOR WESTERN LOCATIONS. LAYER PW VALUES ARE
ON A DOWNWARD TREND BUT WILL STILL BE MOSTLY ABOVE 1 INCH.
WITH SW FLOW ALOFT...EXPECT MORE CLOUDS TO STREAM IN FROM LOW
PRESSURE NEAR THE CAROLINAS. ALONG WITH THIS...THINK THIS
COMBINATION OF INSTABILITY AND FORCING WILL BE SUFFICIENT FOR
ISOLATED TO SCATTERED SHOWERS ESPECIALLY FOR EASTERN COASTAL
SECTIONS. THIS WILL BE IN THE FORM OF MOSTLY LIGHT RAIN WITH ONLY A
SLIGHT CHANCE OF THUNDER LATER THIS AFTERNOON. OUT TOWARDS THE LOWER
HUDSON VALLEY...THERE IS A BETTER CHANCE ESPECIALLY BY LATE
AFTERNOON OF THUNDERSTORM ACTIVITY. SHOWERS AND THUNDERSTORMS
EXPECTED TO START OUT ISOLATED AND GROW TO SCATTERED IN COVERAGE
TOWARDS EARLY EVENING. THE HRRR SHOWS A SIMILAR DEPICTION IN ITS
REFLECTIVITY FIELDS. CONVECTION OVERALL WILL BE LOW TOPPED FROM
20-30KFT. GUSTY WINDS WILL BE POSSIBLE WITH SOME THUNDERSTORMS
ESPECIALLY TOWARDS LOWER HUDSON VALLEY WITH MID LEVEL DRYING AND
HIGHER DCAPE VALUES.
CONCERNING TEMPS...NOT MUCH CHANGE FROM PREVIOUS FORECAST. ONLY
ADJUSTED BY A FEW DEGREES IN SPOTS. MAX TEMPS STILL ABOVE
NORMAL...UPPER 70S TO LOWER 80S FOR MOST LOCATIONS. THE REST OF THE
FORECAST DID NOT HAVE MANY CHANGES EITHER WITH THE LAST UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
COLD FRONT WILL SLOWLY MOVE ACROSS THE AREA TONIGHT WITH PRECIP
ENDING W TO E. A MUCH DRIER AIR MASS WILL BUILD IN BEHIND IT WITH
DEWPOINTS DROPPING INTO THE UPPER 40 TO LOWER 50S BY THU AFTN AS
RIDGING BUILDS IN AT THE SFC AND ALOFT.
MEANWHILE...BERYL IS FORECAST TO TRACK NE FROM THE CAROLINA COAST
PASSING WELL SE OF THE AREA ON THU. REFER TO THE NATIONAL
HURRICANE CENTER FOR THE OFFICIAL TRACK AND INTENSITY FORECASTS.
ONLY POTENTIAL IMPACTS FROM BERYL WILL BE MARINE RELATED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE PERIOD BEGINS FAIRLY QUIET WITH THE REMNANTS TROPICAL CYCLONE
BERYL PASSING WELL TO THE SOUTH AND EAST AND HIGH PRESSURE BUILDING
OVER THE NORTHEAST. PLEASE REFER TO THE NATIONAL HURRICANE CENTER
FOR THE OFFICIAL TRACK AND INTENSITY FORECASTS FOR BERYL. WITH UPPER
LEVEL RIDGING AND SUBSIDENCE BUILDING IN...EXPECT MOSTLY CLEAR SKIES
THURS NIGHT INTO FRI MORNING. AS THE HIGH PUSHES IN..EXPECT WINDS TO
SHIFT FROM A NORTHWESTERLY FLOW...BACK TO AN ONSHORE FLOW...WHICH
WILL AID IN INCREASING THE MOISTURE FIELD AND IN TURN INCREASE CLOUD
COVERAGE FRIDAY. THIS WILL HELP KEEP TEMPS NEAR NORMAL DESPITE 925MB
TEMPS REACHING INTO THE UPPER TEENS.
NOW FOR THE WEEKEND...SEEMS THE MODELS CONTINUE TO SPEED UP THE
PASSAGE OF THE COLD FRONT...WITH THERE BEING GOOD AGREEMENT IN THE
PASSAGE ON SAT. THE WARM FRONT PUSHES THROUGH OVERNIGHT FRI...WITH
THE LOW OVER SOUTHERN CANADA OCCLUDING...THEN DRAGGING THE FRONT
THROUGH. HAVE ADJUSTED POPS TO REFLECT THE LATEST PASSAGE OF THE
FRONT...BRINGING IN CHC FOR THE WESTERN AREAS ON FRIDAY...THEN
SPREADING LIKELY ACROSS THE AREA OVERNIGHT FRI INTO SAT...THEN
DIMINISHING DOWN SAT NIGHT. THE SOUTHERLY FLOW AHEAD OF THE
APPROACHING FRONT INJECTS IN PLENTY OF MOISTURE...WITH PW VALUES
BETWEEN 1.5 AND 2.0 INCHES. VERY LITTLE INSTABILITY IS NOTED HOWEVER
SO HAVE SIDED WITH KEEPING JUST RAIN SHOWERS WITH NO MENTION OF
THUNDER...THOUGH ANY DEVELOPING SHOWERS COULD BE HEAVY AT TIMES
RIGHT AHEAD OF THE FRONT.
THE UPPER LEVEL CLOSED LOW FINALLY PUSHES EAST INTO SE CANADA ON
SUN...BRINGING A VORT MAX RIGHT THROUGH THE REGION SUN AFTN.
THIS...COMBINED WITH A SURFACE TROUGH PASSAGE BETWEEN 18Z AND 00Z
MAY LEAD TO POSSIBLE DEVELOPMENT OF SOME AFTN ISOLATED SHOWERS AND
THUNDERSTORMS WITH SOUNDINGS HINTING AT CAPE VALUES BETWEEN 500 AND
1000 J/KG. THE ORIGINAL SURFACE LOW THEN PUSHES TO THE EAST AND
SETTLES OFFSHORE OF MAINE FOR THE FIRST PART OF THE WEEK WHILE THE
UPPER LEVEL LOW REMAINS NEARLY STATIONARY AND BUILDS ACROSS THE
NORTHEAST. THE 00Z GFS KEEPS THE DEVELOPMENT OF A SURFACE LOW OFF
THE CAROLINAS WHILE THE 00Z ECMWF SHOWS NO DEVELOPMENT YET DEEPENS
THE LOW OFF THE NORTHEAST MORE. WITH THE MODEL DISCREPANCY...SIDED
MOSTLY WITH THE PREVIOUS FORECAST FOR MON INTO WED...KEEPING SLIGHT
CHC POPS AND THE MENTION OF THUNDER FOR THE AFTN HOURS UNDER THE
PERSISTING UPPER LEVEL LOW AND SURFACE LOW TO THE NORTHEAST.
TEMPS WILL FLUCTUATE SLIGHTLY THIS WEEKEND...WITH SLIGHTLY COOLER
AIR MOVING IN BEHIND THE FRONT FOR SAT AND SUN. HOWEVER...TEMPS
REBOUND TO NEAR NORMAL FOR HIGHS AND SLIGHTLY ABOVE NORMAL FOR LOWS
FOR THE START OF THE WEEK.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
A WEAK COLD FRONT WILL APPROACH FROM THE WEST TODAY...AND PASS
THROUGH TONIGHT.
CONDS TODAY WILL REMAIN VFR...WITH OCNL SPRINKLES/SHOWERS FALLING
FROM A BKN-OVC MID LEVEL DECK. THESE CLOUDS SHOULD SCATTER OUT BY
MID TO LATE AFTERNOON.
MEDIUM CONFIDENCE IN SCT SHOWERS/ISOLD TSTMS MAKING IT TO THE NYC
METRO TERMINALS EARLY THIS EVENING. NOT INCLUDING THUNDER ATTM AS
INSTABILITY IS MARGINAL...BUT LOOKS AT LEAST WORTH A MENTION OF
BRIEF MVFR VSBY RESTRICTION.
GENERALLY LIGHT AND VARIABLE WINDS THIS MORNING...TURNING SE AND
THEN S THIS AFTERNOON. WINDS BECOME LIGHT AND VARIABLE ONCE AGAIN
TONIGHT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3023/3101...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
KLGA FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3023/3101...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
KEWR FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3022/3024...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3023/3101...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
KHPN FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3022/3101...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
KISP FCSTER COMMENTS: SLIGHT CHANCE OF THUNDER FROM 3023/3101...
CONFIDENCE NOT HIGH ENOUGH FOR EXPLICIT TAF MENTION.
.OUTLOOK FOR 12Z THU THROUGH SUNDAY...
.THU-FRI...VFR.
.FRI NIGHT-SAT...MVFR OR LOWER POSSIBLE IN SHOWERS/TSTMS.
.SUN...MOSTLY VFR. ONLY SLIGHT CHANCE OF A SHOWER OR TSTM.
&&
.MARINE...
SUB-ADVY CONDS EXPECTED THROUGH THU. WW3 APPEARS TO BE RUNNING
1-2 FT HIGH THROUGH THU AND HAVE ADJUSTED. NEITHER WNA OR NAH
GUIDANCE IS INDICATING SWELLS FROM BERYL UNTIL FRIDAY NIGHT/SAT
RESPECTIVELY...BUT MAY SEE THEM AS EARLY AS THU NIGHT.
WINDS SHOULD REMAIN BELOW SCA CRITERIA INTO THIS WEEKEND. SEAS
HOWEVER...WILL BUILD TO AROUND 5 TO 6 FT ON THE OCEAN WATERS WITH A
COMBINATION OF A PERSISTENT FLOW AND SWELLS FROM THE PASSAGE OF
BERYL TO THE SOUTH AND EAST. THE SEAS WILL REMAIN ELEVATED INTO THE
WEEKEND...WITH THE WINDS INCREASING AHEAD OF THE COLD
FRONT...POSSIBLY TO MARGINAL SCA CONDITIONS.
SEAS AND WINDS DIMINISH IN THE WAKE OF THE COLD FRONT...WITH SUB SCA
CONDITIONS EXPECTED THE END OF THE WEEKEND AND INTO NEXT WEEK.
&&
.HYDROLOGY...
WIDESPREAD SIGNIFICANT RAINFALL IS NOT EXPECTED TODAY.
HOWEVER...PRECIPITABLE WATERS FORECAST NEAR 1.5 INCHES COULD
PRODUCE LOCALLY HEAVY DOWNPOURS IN ANY CONVECTION.
THE NEXT CHANCE FOR SIGNIFICANT RAINFALL WILL BE FRIDAY NIGHT INTO
SATURDAY. 1/2 TO 1 INCH OF BASIN AVERAGE QPF IS EXPECTED AT THIS
TIME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...JM
SHORT TERM...
LONG TERM...
AVIATION...GOODMAN
MARINE...
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS ALBANY NY
1045 AM EDT WED MAY 30 2012
.SYNOPSIS...
ONE COLD FRONT WILL DRIFT SOUTH AND EAST OF THE REGION THIS
MORNING...WHILE A SECONDARY COLD FRONT PASSES THROUGH THE REGION
LATER THIS AFTERNOON. THIS FRONT WILL BE ACCOMPANIED BY ISOLATED TO
SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM. HIGH PRESSURE WILL
BUILD IN FOR THURSDAY...ALONG WITH COOLER AND LESS HUMID CONDITIONS.
A STORM SYSTEM TRACKING INTO THE OHIO VALLEY AND GREAT LAKES WILL
BRING RAIN TO THE REGION LATE FRIDAY INTO EARLY SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1030 AM...PREVIOUS FORECAST GENERALLY IN GOOD SHAPE. HAVE MADE
SOME HOURLY TEMP ADJUSTMENTS TO ACCOUNT FOR CURRENT CONDITIONS AND
ALSO SOME MAX TEMP ADJUSTMENTS FOR TODAY.
****PREVIOUS DISCUSSION****
ANOTHER SHORTWAVE...AND SFC TROUGH WILL APPROACH FROM THE WEST LATE
THIS AFTERNOON. BOTH THE NAM12 AND RAP INDICATE A SMALL SURGE OF
SFC-850 THETA E ADVECTION AHEAD OF THIS FEATURE...MAINLY AFTER 3 PM
FOR AREAS SOUTH OF ALBANY. SHOULD THIS OCCUR...THERE WOULD BE
DEVELOPING INSTABILITY ASSUMING ENOUGH HEATING/SUNSHINE OCCURS PRIOR
TO THIS TIME...WITH NAM FORECAST SOUNDINGS INDICATING 500-800 J/KG
CAPE. THERE IS SOME MID LEVEL CAPPING EARLY THIS AFTERNOON...BUT
THIS CAP WEAKENS ACROSS CENTRAL AND SOUTHERN AREAS LATER THIS
AFTERNOON WITH THE APPROACH OF THE UPPER LEVEL SHORTWAVE. IN
ADDITION...0-6KM BULK SHEAR INCREASES TO 30-40 KT. THE EQUILIBRIUM
LEVEL INCREASES TO AROUND 25000 FT BY LATE AFTERNOON. THE BOTTOM
LINE IS THAT ISOLATED TO SCATTERED SHOWERS...AND A FEW LOW TOPPED
THUNDERSTORMS WILL DEVELOP ACROSS PORTIONS OF THE REGION LATE THIS
AFTERNOON...ESPECIALLY FROM ALBANY SOUTH AND EAST. SOME OF THE
TALLER CONVECTIVE CELLS COULD HAVE LOCALLY GUSTY WINDS AND SMALL
HAIL...BUT NOTHING IN COMPARISON TO THE WIDESPREAD SEVERE WEATHER
FROM YESTERDAY.
HAVE GENERALLY SIDED CLOSER TO THE SLIGHTLY WARMER MAV MOS...GIVEN
SUCH A WARM START...WITH AFTERNOON MAX TEMPS REACHING THE LOWER/MID
80S WITHIN VALLEY REGIONS...AND 75-80 ACROSS HIGHER ELEVATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
TONIGHT...ISOLATED TO SCATTERED SHOWERS...AND A FEW TSTMS MAY
LINGER INTO THIS EVENING FROM ALBANY S AND E...BEFORE DISSIPATING
AND/OR MOVING OUT OF THE REGION PRIOR TO MIDNIGHT.
THEREAFTER...EXPECT CLEARING SKIES...ALONG WITH COOLER AND
SLIGHTLY LESS HUMID CONDITIONS. EXPECT MINS TO FALL INTO THE
LOWER/MID 50S IN VALLEY REGIONS...AND 45-50 ACROSS HIGHER
ELEVATIONS...AS WELL AS PORTIONS OF THE UPPER HUDSON RIVER VALLEY.
THU-THU NT...A WEAK SHORTWAVE TROUGH WILL BRUSH NORTHERN AREAS
DURING THE MORNING HOURS...ACCOMPANIED BY SOME CLOUDS...AND
PERHAPS A COUPLE OF PASSING SHOWERS. OTHERWISE...EXPECT MAINLY
SUNNY CONDITIONS...ALONG WITH COOLER AND LESS HUMID CONDITIONS.
HAVE SIDED CLOSE TO THE WARMER MAV MOS FOR TEMPS...BASED ON RECENT
PERFORMANCE...WITH FORECAST MAXES IN THE MID/UPPER 70S IN
VALLEYS...AND 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FOR THU
NT...EXPECT CLEAR SKIES TO START...FOLLOWED BY SOME INCREASING
CLOUDS LATE...ESP ACROSS S/W AREAS. IT SHOULD BE RATHER COOL AND
COMFORTABLE...WITH MINS FALLING INTO THE UPPER 40S TO LOWER 50S IN
VALLEYS...AND PERHAPS SOME LOWER 40S ACROSS HIGHER ELEVATIONS
WITHIN THE NORTH COUNTRY AND WESTERN NEW ENGLAND.
FRI-FRI NT...MODELS ARE FAIRLY CONSISTENT WITH THE OVERALL
SYNOPTIC SITUATION...WITH A RATHER STRONG LOW PRESSURE SYSTEM
TRACKING THROUGH THE OHIO VALLEY TOWARD THE CENTRAL OR EASTERN
GREAT LAKES...AND A WARM/OCCLUDED FRONT APPROACHING OUR REGION FROM
THE SOUTHWEST. HOWEVER...TIMING DIFFERENCE STILL EXIST...WITH THE
00Z/30 NAM AND ECMWF BRINGING PRECIP FASTER INTO THE REGION FOR FRI
AFTERNOON...WHILE THE GFS/GEM HOLD IT OFF LONGER...UNTIL FRI EVE.
THE NAM SEEMS MOST AGGRESSIVE...WITH A PERIOD OF MODERATE RAIN OR
SHOWERS OCCURRING ACROSS PORTIONS OF THE MOHAWK VALLEY AS EARLY AS
FRI AFTERNOON...IN ASSOCIATION WITH STRONG MID LEVEL
FRONTOGENETICAL FORCING. AT THIS TIME...NOT COMPLETELY SOLD ON
THIS...BUT ACKNOWLEDGE THAT SOME RAIN COULD BREAK OUT IN PORTIONS
OF THE REGION FRI AFTERNOON...WITH CHC POPS AFTER A DRY FRI
MORNING. THEN...LIKELY POPS ALL AREAS FOR FRI NT AS A SOAKING RAIN
OCCURS. FOR TEMPS...SIDED A BIT CLOSER TO THE WARMER MAV MOS FOR
FRI...ASSUMING SOME SUNSHINE OCCURS IN THE MORNING...AND RAIN
HOLDS OFF LONG ENOUGH TO ALLOW TEMPS TO REACH THE UPPER 60S TO
LOWER TO MID 70S. HOWEVER...SHOULD MODERATE RAIN DEVELOP AS
QUICKLY AS THE NAM SUGGESTS...MUCH COOLER MAXES WOULD BE POSSIBLE.
FOR FRI NT...EXPECT MINS TO FALL INTO THE LOWER/MID 50S IN
VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A BLEND OF THE GFS/ECMWF/HPC GUIDANCE WAS UTILIZED WHICH POINTS
TOWARD A PATTERN CHANGE FOR THIS FIRST WEEKEND OF JUNE.
A RATHER STRONG COLD FRONT IS POISED TO BE EAST OF THE HUDSON RIVER
SATURDAY MORNING TAKING ITS ASSOCIATED RAINFALL/SHOWERS INTO NEW
ENGLAND AND FURTHER EASTWARD. IN ITS WAKE...A COOL AND MOIST
CYCLONIC FLOW EVOLVES AS A VERTICALLY STACKED LOW BECOMES
QUASI-STATIONARY OVER LOWER ONTARIO AND QUEBEC PROVENCE THIS
WEEKEND. WHILE TIMING OF INDIVIDUAL SHORT WAVES REMAINS IN
QUESTION...IT APPEARS DIURNALLY DRIVEN SHOWERS WILL BE THE RESULT.
THERE ARE ADDITIONAL TRENDS SEEN IN THE GUIDANCE THIS MORNING OF
THIS UPPER LOW REFORMING OVER THE GULF OF MAINE WHICH WOULD KEEP THE
COOL AND MOIST CYCLONIC FLOW /ALONG WITH ATLANTIC MOIST CONVEYOR
BELT/ INTO THE BEGINNING OF NEXT WEEK.
THIS WILL KEEP TEMPERATURES AT OR BELOW NORMAL THROUGH MOST OF THE
LONG TERM PERIOD WITH PRECIPITATION AT OR ABOVE NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WIDELY SCATTERED SHOWERS MAY DRIFT ACROSS THE REGION THIS MORNING
MAINLY SOUTH OF I90. HOWEVER...MAINLY VFR CONDITIONS THIS MORNING
WITH A BROKEN AC DECK. ONCE DAYTIME HEATING COMMENCES....SOME
AFTERNOON SHOWERS WITH AN ISOLATED THUNDERSTORM POSSIBLE WITH THE
HIGHER CHANCES SOUTH OF KGFL /WHERE NO MENTION OF SHOWERS ARE
FORECAST/. WITH FAVORABLE UPSLOPE CONDITIONS...WE WILL PLACE
SHOWERS FOR KPSF THIS AFTERNOON INTO EARLY THIS EVENING.
SOUTHWESTERLY WINDS WILL SHIFT TO WESTERLY OVERNIGHT AND THEN
WEST-NORTHWESTERLY WITH THE PASSAGE OF THE COLD FRONT LATER
WEDNESDAY.
OUTLOOK...
THU-FRI...VFR...NO SIG WX.
FRI NT-SAT AM...MVFR/IFR. RA LIKELY.
SAT PM-SUN...VFR/MVFR. CHC -SHRAS.
&&
.FIRE WEATHER...
A SECONDARY COLD FRONT WILL APPROACH FROM THE WEST LATE THIS
AFTERNOON...TRIGGERING ISOLATATED TO SCATTERED SHOWERS...AND
PERHAPS A THUNDERSTORM FOR AREAS MAINLY NEAR AND SOUTH OF ALBANY.
FAIR AND COOLER CONDITIONS WILL DEVELOP AS HIGH PRESSURE BUILDS
INTO THE REGION FOR TONIGHT INTO THURSDAY.
THE RH WILL FALL INTO THE 35-45 PERCENT RANGE THIS
AFTERNOON...THEN RECOVER TO 80-100 PERCENT TONIGHT WITH AREAS OF
DEW FORMATION LIKELY. THE RH WILL THEN FALL INTO THE 30-40 PERCENT
RANGE FOR THU AFTERNOON.
WINDS WILL BECOME SOUTHWEST TO WEST AT 10-20 MPH THIS
AFTERNOON...THEN WILL BECOME NORTHWEST AT LESS THAN 5 MPH
TONIGHT. ON THURSDAY...EXPECT WEST TO NORTHWEST WINDS TO INCREASE
TO 15-25 MPH.
&&
.HYDROLOGY...
NUMEROUS SHOWERS AND THUNDERSTORMS TUESDAY LED TO SOME RIVER
RISES...ESPECIALLY WITHIN PORTIONS OF THE WESTERN MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...AND SOUTHERN VT...WHERE RISES OF
2-3 FT OCCURRED. THESE RIVER LEVELS HAVE ALREADY STARTED DROPPING.
ISOLATED TO SCATTERED SHOWERS/TSTMS ARE POSSIBLE THIS AFTERNOON
AND EVENING...WITH POINT RAINFALL AMOUNTS GENERALLY REMAINING
UNDER ONE QUARTER OF AN INCH. THIS SHOULD CAUSE MINIMAL RIVER
RESPONSES.
A WIDESPREAD RAINFALL IS EXPECTED LATE FRIDAY INTO EARLY
SATURDAY...WITH RAINFALL AMOUNTS OF 0.50-1 INCH POSSIBLE. THIS MAY
CAUSE ADDITIONAL WITHIN BANK RISES ON AREA RIVERS/STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM/KL
NEAR TERM...GJM/KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...GJM/BGM
FIRE WEATHER...KL
HYDROLOGY...KL/IAA/11
AREA FORECAST DISCUSSION
NWS ALBANY NY
725 AM EDT WED MAY 30 2012
.SYNOPSIS...
ONE COLD FRONT WILL DRIFT SOUTH AND EAST OF THE REGION
THIS MORNING...WHILE ANOTHER SECONDARY COLD FRONT PASSES LATE THIS
AFTERNOON. THIS SECOND FRONT WILL BE ACCOMPANIED BY ISOLATED TO
SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM. HIGH PRESSURE WILL
BUILD IN FOR THURSDAY...ALONG WITH COOLER AND LESS HUMID
CONDITIONS. A STORM SYSTEM TRACKING INTO THE OHIO VALLEY AND GREAT
LAKES WILL BRING RAIN TO THE REGION LATE FRIDAY INTO EARLY
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 650 AM EDT...JUST A FEW ISOLATED LIGHT SHOWERS/SPRINKLES ARE
OCCURRING...MAINLY ACROSS THE TACONICS...BERKSHIRES AND SOUTHERN
GREENS...AS WELL AS ACROSS PORTIONS OF THE MID HUDSON VALLEY. WILL
RETAIN SLIGHT CHC POPS FROM ALBANY S AND E THROUGH AROUND 14Z TO
ACCCOUNT FOR LINGERING SHOWERS/SPRINKLES.
HIGH AND MID LEVEL CLOUDS WILL PERSIST THROUGH THE MORNING
HOURS...WITH GRADUAL CLEARING EXPECTED FROM W TO E THIS AFTERNOON.
ANOTHER SHORTWAVE...AND SFC TROUGH WILL APPROACH FROM THE WEST
LATE THIS AFTERNOON. BOTH THE NAM12 AND RAP INDICATE A SMALL SURGE
OF SFC-850 THETA E ADVECTION AHEAD OF THIS FEATURE...MAINLY AFTER
3 PM FOR AREAS SOUTH OF ALBANY. SHOULD THIS OCCUR...THERE WOULD BE
DEVELOPING INSTABILITY ASSUMING ENOUGH HEATING/SUNSHINE OCCURS
PRIOR TO THIS TIME...WITH NAM FORECAST SOUNDINGS INDICATING
500-800 J/KG CAPE. THERE IS SOME MID LEVEL CAPPING EARLY THIS
AFTERNOON...BUT THIS CAP WEAKENS ACROSS CENTRAL AND SOUTHERN AREAS
LATER THIS AFTERNOON WITH THE APPROACH OF THE UPPER LEVEL
SHORTWAVE. IN ADDITION...0-6KM BULK SHEAR INCREASES TO 30-40 KT.
THE EQUILIBRIUM LEVEL INCREASES TO AROUND 25000 FT BY LATE
AFTERNOON. THE BOTTOM LINE IS THAT ISOLATED TO SCATTERED
SHOWERS...AND A FEW LOW TOPPED THUNDERSTORMS WILL DEVELOP ACROSS
PORTIONS OF THE REGION LATE THIS AFTERNOON...ESPECIALLY FROM
ALBANY SOUTH AND EAST. SOME OF THE TALLER CONVECTIVE CELLS COULD
HAVE LOCALLY GUSTY WINDS AND SMALL HAIL...BUT NOTHING IN
COMPARISON TO THE WIDESPREAD SEVERE WEATHER FROM YESTERDAY.
HAVE GENERALLY SIDED CLOSER TO THE SLIGHTLY WARMER MAV MOS...GIVEN
SUCH A WARM START...WITH AFTERNOON MAX TEMPS REACHING THE LOWER/MID
80S WITHIN VALLEY REGIONS...AND 75-80 ACROSS HIGHER ELEVATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
TONIGHT...ISOLATED TO SCATTERED SHOWERS...AND A FEW TSTMS MAY
LINGER INTO THIS EVENING FROM ALBANY S AND E...BEFORE DISSIPATING
AND/OR MOVING OUT OF THE REGION PRIOR TO MIDNIGHT.
THEREAFTER...EXPECT CLEARING SKIES...ALONG WITH COOLER AND
SLIGHTLY LESS HUMID CONDITIONS. EXPECT MINS TO FALL INTO THE
LOWER/MID 50S IN VALLEY REGIONS...AND 45-50 ACROSS HIGHER
ELEVATIONS...AS WELL AS PORTIONS OF THE UPPER HUDSON RIVER VALLEY.
THU-THU NT...A WEAK SHORTWAVE TROUGH WILL BRUSH NORTHERN AREAS
DURING THE MORNING HOURS...ACCOMPANIED BY SOME CLOUDS...AND
PERHAPS A COUPLE OF PASSING SHOWERS. OTHERWISE...EXPECT MAINLY
SUNNY CONDITIONS...ALONG WITH COOLER AND LESS HUMID CONDITIONS.
HAVE SIDED CLOSE TO THE WARMER MAV MOS FOR TEMPS...BASED ON RECENT
PERFORMANCE...WITH FORECAST MAXES IN THE MID/UPPER 70S IN
VALLEYS...AND 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FOR THU
NT...EXPECT CLEAR SKIES TO START...FOLLOWED BY SOME INCREASING
CLOUDS LATE...ESP ACROSS S/W AREAS. IT SHOULD BE RATHER COOL AND
COMFORTABLE...WITH MINS FALLING INTO THE UPPER 40S TO LOWER 50S IN
VALLEYS...AND PERHAPS SOME LOWER 40S ACROSS HIGHER ELEVATIONS
WITHIN THE NORTH COUNTRY AND WESTERN NEW ENGLAND.
FRI-FRI NT...MODELS ARE FAIRLY CONSISTENT WITH THE OVERALL
SYNOPTIC SITUATION...WITH A RATHER STRONG LOW PRESSURE SYSTEM
TRACKING THROUGH THE OHIO VALLEY TOWARD THE CENTRAL OR EASTERN
GREAT LAKES...AND A WARM/OCCLUDED FRONT APPROACHING OUR REGION FROM
THE SOUTHWEST. HOWEVER...TIMING DIFFERENCE STILL EXIST...WITH THE
00Z/30 NAM AND ECMWF BRINGING PRECIP FASTER INTO THE REGION FOR FRI
AFTERNOON...WHILE THE GFS/GEM HOLD IT OFF LONGER...UNTIL FRI EVE.
THE NAM SEEMS MOST AGGRESSIVE...WITH A PERIOD OF MODERATE RAIN OR
SHOWERS OCCURRING ACROSS PORTIONS OF THE MOHAWK VALLEY AS EARLY AS
FRI AFTERNOON...IN ASSOCIATION WITH STRONG MID LEVEL
FRONTOGENETICAL FORCING. AT THIS TIME...NOT COMPLETELY SOLD ON
THIS...BUT ACKNOWLEDGE THAT SOME RAIN COULD BREAK OUT IN PORTIONS
OF THE REGION FRI AFTERNOON...WITH CHC POPS AFTER A DRY FRI
MORNING. THEN...LIKELY POPS ALL AREAS FOR FRI NT AS A SOAKING RAIN
OCCURS. FOR TEMPS...SIDED A BIT CLOSER TO THE WARMER MAV MOS FOR
FRI...ASSUMING SOME SUNSHINE OCCURS IN THE MORNING...AND RAIN
HOLDS OFF LONG ENOUGH TO ALLOW TEMPS TO REACH THE UPPER 60S TO
LOWER TO MID 70S. HOWEVER...SHOULD MODERATE RAIN DEVELOP AS
QUICKLY AS THE NAM SUGGESTS...MUCH COOLER MAXES WOULD BE POSSIBLE.
FOR FRI NT...EXPECT MINS TO FALL INTO THE LOWER/MID 50S IN
VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A BLEND OF THE GFS/ECMWF/HPC GUIDANCE WAS UTILIZED WHICH POINTS
TOWARD A PATTERN CHANGE FOR THIS FIRST WEEKEND OF JUNE.
A RATHER STRONG COLD FRONT IS POISED TO BE EAST OF THE HUDSON RIVER
SATURDAY MORNING TAKING ITS ASSOCIATED RAINFALL/SHOWERS INTO NEW
ENGLAND AND FURTHER EASTWARD. IN ITS WAKE...A COOL AND MOIST
CYCLONIC FLOW EVOLVES AS A VERTICALLY STACKED LOW BECOMES
QUASI-STATIONARY OVER LOWER ONTARIO AND QUEBEC PROVENCE THIS
WEEKEND. WHILE TIMING OF INDIVIDUAL SHORT WAVES REMAINS IN
QUESTION...IT APPEARS DIURNALLY DRIVEN SHOWERS WILL BE THE RESULT.
THERE ARE ADDITIONAL TRENDS SEEN IN THE GUIDANCE THIS MORNING OF
THIS UPPER LOW REFORMING OVER THE GULF OF MAINE WHICH WOULD KEEP THE
COOL AND MOIST CYCLONIC FLOW /ALONG WITH ATLANTIC MOIST CONVEYOR
BELT/ INTO THE BEGINNING OF NEXT WEEK.
THIS WILL KEEP TEMPERATURES AT OR BELOW NORMAL THROUGH MOST OF THE
LONG TERM PERIOD WITH PRECIPITATION AT OR ABOVE NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WIDELY SCATTERED SHOWERS MAY DRIFT ACROSS THE REGION THIS MORNING
MAINLY SOUTH OF I90. HOWEVER...MAINLY VFR CONDITIONS THIS MORNING
WITH A BROKEN AC DECK. ONCE DAYTIME HEATING COMMENCES....SOME
AFTERNOON SHOWERS WITH AN ISOLATED THUNDERSTORM POSSIBLE WITH THE
HIGHER CHANCES SOUTH OF KGFL /WHERE NO MENTION OF SHOWERS ARE
FORECAST/. WITH FAVORABLE UPSLOPE CONDITIONS...WE WILL PLACE
SHOWERS FOR KPSF THIS AFTERNOON INTO EARLY THIS EVENING.
SOUTHWESTERLY WINDS WILL SHIFT TO WESTERLY OVERNIGHT AND THEN
WEST-NORTHWESTERLY WITH THE PASSAGE OF THE COLD FRONT LATER
WEDNESDAY.
OUTLOOK...
THU-FRI...VFR...NO SIG WX.
FRI NT-SAT AM...MVFR/IFR. RA LIKELY.
SAT PM-SUN...VFR/MVFR. CHC -SHRAS.
&&
.FIRE WEATHER...
A SECONDARY COLD FRONT WILL APPROACH FROM THE WEST LATE THIS
AFTERNOON...TRIGGERING ISOLATATED TO SCATTERED SHOWERS...AND
PERHAPS A THUNDERSTORM FOR AREAS MAINLY NEAR AND SOUTH OF ALBANY.
FAIR AND COOLER CONDITIONS WILL DEVELOP AS HIGH PRESSURE BUILDS
INTO THE REGION FOR TONIGHT INTO THURSDAY.
THE RH WILL FALL INTO THE 35-45 PERCENT RANGE THIS
AFTERNOON...THEN RECOVER TO 80-100 PERCENT TONIGHT WITH AREAS OF
DEW FORMATION LIKELY. THE RH WILL THEN FALL INTO THE 30-40 PERCENT
RANGE FOR THU AFTERNOON.
WINDS WILL BECOME SOUTHWEST TO WEST AT 10-20 MPH THIS
AFTERNOON...THEN WILL BECOME NORTHWEST AT LESS THAN 5 MPH
TONIGHT. ON THURSDAY...EXPECT WEST TO NORTHWEST WINDS TO INCREASE
TO 15-25 MPH.
&&
.HYDROLOGY...
NUMEROUS SHOWERS AND THUNDERSTORMS TUESDAY LED TO SOME RIVER
RISES...ESPECIALLY WITHIN PORTIONS OF THE WESTERN MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...AND SOUTHERN VT...WHERE RISES OF
2-3 FT OCCURRED. THESE RIVER LEVELS HAVE ALREADY STARTED DROPPING.
ISOLATED TO SCATTERED SHOWERS/TSTMS ARE POSSIBLE THIS AFTERNOON
AND EVENING...WITH POINT RAINFALL AMOUNTS GENERALLY REMAINING
UNDER ONE QUARTER OF AN INCH. THIS SHOULD CAUSE MINIMAL RIVER
RESPONSES.
A WIDESPREAD RAINFALL IS EXPECTED LATE FRIDAY INTO EARLY
SATURDAY...WITH RAINFALL AMOUNTS OF 0.50-1 INCH POSSIBLE. THIS MAY
CAUSE ADDITIONAL WITHIN BANK RISES ON AREA RIVERS/STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/IAA
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...GJM/BGM
FIRE WEATHER...KL
HYDROLOGY...KL/IAA/11
AREA FORECAST DISCUSSION
NWS ALBANY NY
659 AM EDT WED MAY 30 2012
.SYNOPSIS...
ONE COLD FRONT WILL DRIFT SOUTH AND EAST OF THE REGION
THIS MORNING...WHILE ANOTHER SECONDARY COLD FRONT PASSES LATE THIS
AFTERNOON. THIS SECOND FRONT WILL BE ACCOMPANIED BY ISOLATED TO
SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM. HIGH PRESSURE WILL
BUILD IN FOR THURSDAY...ALONG WITH COOLER AND LESS HUMID
CONDITIONS. A STORM SYSTEM TRACKING INTO THE OHIO VALLEY AND GREAT
LAKES WILL BRING RAIN TO THE REGION LATE FRIDAY INTO EARLY
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 650 AM EDT...JUST A FEW ISOLATED LIGHT SHOWERS/SPRINKLES ARE
OCCURRING...MAINLY ACROSS THE TACONICS...BERKSHIRES AND SOUTHERN
GREENS...AS WELL AS ACROSS PORTIONS OF THE MID HUDSON VALLEY. WILL
RETAIN SLIGHT CHC POPS FROM ALBANY S AND E THROUGH AROUND 14Z TO
ACCCOUNT FOR LINGERING SHOWERS/SPRINKLES.
HIGH AND MID LEVEL CLOUDS WILL PERSIST THROUGH THE MORNING
HOURS...WITH GRADUAL CLEARING EXPECTED FROM W TO E THIS AFTERNOON.
ANOTHER SHORTWAVE...AND SFC TROUGH WILL APPROACH FROM THE WEST
LATE THIS AFTERNOON. BOTH THE NAM12 AND RAP INDICATE A SMALL SURGE
OF SFC-850 THETA E ADVECTION AHEAD OF THIS FEATURE...MAINLY AFTER
3 PM FOR AREAS SOUTH OF ALBANY. SHOULD THIS OCCUR...THERE WOULD BE
DEVELOPING INSTABILITY ASSUMING ENOUGH HEATING/SUNSHINE OCCURS
PRIOR TO THIS TIME...WITH NAM FORECAST SOUNDINGS INDICATING
500-800 J/KG CAPE. THERE IS SOME MID LEVEL CAPPING EARLY THIS
AFTERNOON...BUT THIS CAP WEAKENS ACROSS CENTRAL AND SOUTHERN AREAS
LATER THIS AFTERNOON WITH THE APPROACH OF THE UPPER LEVEL
SHORTWAVE. IN ADDITION...0-6KM BULK SHEAR INCREASES TO 30-40 KT.
THE EQUILIBRIUM LEVEL INCREASES TO AROUND 25000 FT BY LATE
AFTERNOON. THE BOTTOM LINE IS THAT ISOLATED TO SCATTERED
SHOWERS...AND A FEW LOW TOPPED THUNDERSTORMS WILL DEVELOP ACROSS
PORTIONS OF THE REGION LATE THIS AFTERNOON...ESPECIALLY FROM
ALBANY SOUTH AND EAST. SOME OF THE TALLER CONVECTIVE CELLS COULD
HAVE LOCALLY GUSTY WINDS AND SMALL HAIL...BUT NOTHING IN
COMPARISON TO THE WIDESPREAD SEVERE WEATHER FROM YESTERDAY.
HAVE GENERALLY SIDED CLOSER TO THE SLIGHTLY WARMER MAV MOS...GIVEN
SUCH A WARM START...WITH AFTERNOON MAX TEMPS REACHING THE LOWER/MID
80S WITHIN VALLEY REGIONS...AND 75-80 ACROSS HIGHER ELEVATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
TONIGHT...ISOLATED TO SCATTERED SHOWERS...AND A FEW TSTMS MAY
LINGER INTO THIS EVENING FROM ALBANY S AND E...BEFORE DISSIPATING
AND/OR MOVING OUT OF THE REGION PRIOR TO MIDNIGHT.
THEREAFTER...EXPECT CLEARING SKIES...ALONG WITH COOLER AND
SLIGHTLY LESS HUMID CONDITIONS. EXPECT MINS TO FALL INTO THE
LOWER/MID 50S IN VALLEY REGIONS...AND 45-50 ACROSS HIGHER
ELEVATIONS...AS WELL AS PORTIONS OF THE UPPER HUDSON RIVER VALLEY.
THU-THU NT...A WEAK SHORTWAVE TROUGH WILL BRUSH NORTHERN AREAS
DURING THE MORNING HOURS...ACCOMPANIED BY SOME CLOUDS...AND
PERHAPS A COUPLE OF PASSING SHOWERS. OTHERWISE...EXPECT MAINLY
SUNNY CONDITIONS...ALONG WITH COOLER AND LESS HUMID CONDITIONS.
HAVE SIDED CLOSE TO THE WARMER MAV MOS FOR TEMPS...BASED ON RECENT
PERFORMANCE...WITH FORECAST MAXES IN THE MID/UPPER 70S IN
VALLEYS...AND 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FOR THU
NT...EXPECT CLEAR SKIES TO START...FOLLOWED BY SOME INCREASING
CLOUDS LATE...ESP ACROSS S/W AREAS. IT SHOULD BE RATHER COOL AND
COMFORTABLE...WITH MINS FALLING INTO THE UPPER 40S TO LOWER 50S IN
VALLEYS...AND PERHAPS SOME LOWER 40S ACROSS HIGHER ELEVATIONS
WITHIN THE NORTH COUNTRY AND WESTERN NEW ENGLAND.
FRI-FRI NT...MODELS ARE FAIRLY CONSISTENT WITH THE OVERALL
SYNOPTIC SITUATION...WITH A RATHER STRONG LOW PRESSURE SYSTEM
TRACKING THROUGH THE OHIO VALLEY TOWARD THE CENTRAL OR EASTERN
GREAT LAKES...AND A WARM/OCCLUDED FRONT APPROACHING OUR REGION FROM
THE SOUTHWEST. HOWEVER...TIMING DIFFERENCE STILL EXIST...WITH THE
00Z/30 NAM AND ECMWF BRINGING PRECIP FASTER INTO THE REGION FOR FRI
AFTERNOON...WHILE THE GFS/GEM HOLD IT OFF LONGER...UNTIL FRI EVE.
THE NAM SEEMS MOST AGGRESSIVE...WITH A PERIOD OF MODERATE RAIN OR
SHOWERS OCCURRING ACROSS PORTIONS OF THE MOHAWK VALLEY AS EARLY AS
FRI AFTERNOON...IN ASSOCIATION WITH STRONG MID LEVEL
FRONTOGENETICAL FORCING. AT THIS TIME...NOT COMPLETELY SOLD ON
THIS...BUT ACKNOWLEDGE THAT SOME RAIN COULD BREAK OUT IN PORTIONS
OF THE REGION FRI AFTERNOON...WITH CHC POPS AFTER A DRY FRI
MORNING. THEN...LIKELY POPS ALL AREAS FOR FRI NT AS A SOAKING RAIN
OCCURS. FOR TEMPS...SIDED A BIT CLOSER TO THE WARMER MAV MOS FOR
FRI...ASSUMING SOME SUNSHINE OCCURS IN THE MORNING...AND RAIN
HOLDS OFF LONG ENOUGH TO ALLOW TEMPS TO REACH THE UPPER 60S TO
LOWER TO MID 70S. HOWEVER...SHOULD MODERATE RAIN DEVELOP AS
QUICKLY AS THE NAM SUGGESTS...MUCH COOLER MAXES WOULD BE POSSIBLE.
FOR FRI NT...EXPECT MINS TO FALL INTO THE LOWER/MID 50S IN
VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A BLEND OF THE GFS/ECMWF/HPC GUIDANCE WAS UTILIZED WHICH POINTS
TOWARD A PATTERN CHANGE FOR THIS FIRST WEEKEND OF JUNE.
A RATHER STRONG COLD FRONT IS POISED TO BE EAST OF THE HUDSON RIVER
SATURDAY MORNING TAKING ITS ASSOCIATED RAINFALL/SHOWERS INTO NEW
ENGLAND AND FURTHER EASTWARD. IN ITS WAKE...A COOL AND MOIST
CYCLONIC FLOW EVOLVES AS A VERTICALLY STACKED LOW BECOMES
QUASI-STATIONARY OVER LOWER ONTARIO AND QUEBEC PROVENCE THIS
WEEKEND. WHILE TIMING OF INDIVIDUAL SHORT WAVES REMAINS IN
QUESTION...IT APPEARS DIURNALLY DRIVEN SHOWERS WILL BE THE RESULT.
THERE ARE ADDITIONAL TRENDS SEEN IN THE GUIDANCE THIS MORNING OF
THIS UPPER LOW REFORMING OVER THE GULF OF MAINE WHICH WOULD KEEP THE
COOL AND MOIST CYCLONIC FLOW /ALONG WITH ATLANTIC MOIST CONVEYOR
BELT/ INTO THE BEGINNING OF NEXT WEEK.
THIS WILL KEEP TEMPERATURES AT OR BELOW NORMAL THROUGH MOST OF THE
LONG TERM PERIOD WITH PRECIPITATION AT OR ABOVE NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WIDELY SCATTERED SHOWERS MAY DRIFT ACROSS THE REGION THE REMAINDER
OF THE OVERNIGHT PERIOD. SHOWER POTENTIAL ALONG WITH WET GROUND AND
PARTIAL CLEARING...MVFR ARE EXPECTED WITH IFR POSSIBLE ESPECIALLY AT
KGFL/KPSF. AN IMPROVEMENT TO VFR EXPECTED AFTER SUNRISE WITH VFR
PERSISTING THROUGH THE MORNING. SOME AFTERNOON SHOWERS WITH AN
ISOLATED THUNDERSTORM POSSIBLE ON WEDNESDAY AFTERNOON AND WE WILL
PLACE A VCSH.
SOUTHWESTERLY WINDS WILL SHIFT TO WESTERLY OVERNIGHT AND THEN
WEST-NORTHWESTERLY WITH THE PASSAGE OF THE COLD FRONT LATER
WEDNESDAY.
OUTLOOK...
WED NT...IMPROVING TO VFR. SLIGHT CHC SHRA/TSRA EARLY.
THU-FRI...VFR...NO SIG WX.
FRI NT...VFR/MVFR. CHC SHRAS WITH IFR CONDITIONS.
SAT-SUN...VFR/MVFR. CHC -SHRAS
&&
.FIRE WEATHER...
A SECONDARY COLD FRONT WILL APPROACH FROM THE WEST LATE THIS
AFTERNOON...TRIGGERING ISOLATATED TO SCATTERED SHOWERS...AND
PERHAPS A THUNDERSTORM FOR AREAS MAINLY NEAR AND SOUTH OF ALBANY.
FAIR AND COOLER CONDITIONS WILL DEVELOP AS HIGH PRESSURE BUILDS
INTO THE REGION FOR TONIGHT INTO THURSDAY.
THE RH WILL FALL INTO THE 35-45 PERCENT RANGE THIS
AFTERNOON...THEN RECOVER TO 80-100 PERCENT TONIGHT WITH AREAS OF
DEW FORMATION LIKELY. THE RH WILL THEN FALL INTO THE 30-40 PERCENT
RANGE FOR THU AFTERNOON.
WINDS WILL BECOME SOUTHWEST TO WEST AT 10-20 MPH THIS
AFTERNOON...THEN WILL BECOME NORTHWEST AT LESS THAN 5 MPH
TONIGHT. ON THURSDAY...EXPECT WEST TO NORTHWEST WINDS TO INCREASE
TO 15-25 MPH.
&&
.HYDROLOGY...
NUMEROUS SHOWERS AND THUNDERSTORMS TUESDAY LED TO SOME RIVER
RISES...ESPECIALLY WITHIN PORTIONS OF THE WESTERN MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...AND SOUTHERN VT...WHERE RISES OF
2-3 FT OCCURRED. THESE RIVER LEVELS HAVE ALREADY STARTED DROPPING.
ISOLATED TO SCATTERED SHOWERS/TSTMS ARE POSSIBLE THIS AFTERNOON
AND EVENING...WITH POINT RAINFALL AMOUNTS GENERALLY REMAINING
UNDER ONE QUARTER OF AN INCH. THIS SHOULD CAUSE MINIMAL RIVER
RESPONSES.
A WIDESPREAD RAINFALL IS EXPECTED LATE FRIDAY INTO EARLY
SATURDAY...WITH RAINFALL AMOUNTS OF 0.50-1 INCH POSSIBLE. THIS MAY
CAUSE ADDITIONAL WITHIN BANK RISES ON AREA RIVERS/STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/IAA
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...KL
HYDROLOGY...KL/IAA/11
AREA FORECAST DISCUSSION
NWS ALBANY NY
505 AM EDT WED MAY 30 2012
.SYNOPSIS...
ONE COLD FRONT WILL DRIFT SOUTH AND EAST OF THE REGION
THIS MORNING...WHILE ANOTHER SECONDARY COLD FRONT PASSES LATE THIS
AFTERNOON. THIS SECOND FRONT WILL BE ACCOMPANIED BY ISOLATED TO
SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM. HIGH PRESSURE WILL
BUILD IN FOR THURSDAY...ALONG WITH COOLER AND LESS HUMID
CONDITIONS. A STORM SYSTEM TRACKING INTO THE OHIO VALLEY AND GREAT
LAKES WILL BRING RAIN TO THE REGION LATE FRIDAY INTO EARLY
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 5 AM EDT...JUST A FEW ISOLATED LIGHT SHOWERS/SPRINKLES ARE
OCCURRING...MAINLY ACROSS THE TACONICS...BERKSHIRES AND SOUTHERN
GREENS...AS WELL AS ACROSS PORTIONS OF THE ID HUDSON VALLEY. WILL
RETAIN SLIGHT CHC POPS ACROSS SE AREAS THROUGH AROUND 12Z TO
ACCCOUNT FOR LINGERING SHOWERS. PATCHY FOG MAY STILL FORM IN SOME
AREAS...ALTHOUGH THE THICK BLANKET OF MID AND HIGH LEVEL CLOUDS
HAS PREVENTED WIDESPREAD DENSE FOG FROM FORMING...DESPITE AN
EXTREMELY MOIST BOUNDARY LAYER AND LIGHT WINDS.
HIGH AND MID LEVEL CLOUDS WILL PERSIST THROUGH THE MORNING
HOURS...WITH GRADUAL CLEARING EXPECTED FROM W TO E THIS AFTERNOON.
ANOTHER SHORTWAVE...AND SFC TROUGH WILL APPROACH FROM THE WEST
LATE THIS AFTERNOON. BOTH THE NAM12 AND RAP INDICATE A SMALL SURGE
OF SFC-850 THETA E ADVECTION AHEAD OF THIS FEATURE...MAINLY AFTER
3 PM FOR AREAS SOUTH OF ALBANY. SHOULD THIS OCCUR...THERE WOULD BE
DEVELOPING INSTABILITY ASSUMING ENOUGH HEATING/SUNSHINE OCCURS
PRIOR TO THIS TIME...WITH NAM FORECAST SOUNDINGS INDICATING
500-800 J/KG CAPE. THERE IS SOME MID LEVEL CAPPING EARLY THIS
AFTERNOON...BUT THIS CAP WEAKENS ACROSS CENTRAL AND SOUTHERN AREAS
LATER THIS AFTERNOON WITH THE APPROACH OF THE UPPER LEVEL
SHORTWAVE. IN ADDITION...0-6KM BULK SHEAR INCREASES TO 30-40 KT.
THE EQUILIBRIUM LEVEL INCREASES TO AROUND 25000 FT BY LATE
AFTERNOON. THE BOTTOM LINE IS THAT ISOLATED TO SCATTERED
SHOWERS...AND A FEW LOW TOPPED THUNDERSTORMS WILL DEVELOP ACROSS
PORTIONS OF THE REGION LATE THIS AFTERNOON...ESPECIALLY FROM
ALBANY SOUTH AND EAST. SOME OF THE TALLER CONVECTIVE CELLS COULD
HAVE LOCALLY GUSTY WINDS AND SMALL HAIL...BUT NOTHING IN
COMPARISON TO THE WIDESPREAD SEVERE WEATHER FROM YESTERDAY.
HAVE GENERALLY SIDED CLOSER TO THE SLIGHTLY WARMER MAV MOS...GIVEN
SUCH A WARM START...WITH AFTERNOON MAX TEMPS REACHING THE LOWER/MID
80S WITHIN VALLEY REGIONS...AND 75-80 ACROSS HIGHER ELEVATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
TONIGHT...ISOLATED TO SCATTERED SHOWERS...AND A FEW TSTMS MAY
LINGER INTO THIS EVENING FROM ALBANY S AND E...BEFORE DISSIPATING
AND/OR MOVING OUT OF THE REGION PRIOR TO MIDNIGHT.
THEREAFTER...EXPECT CLEARING SKIES...ALONG WITH COOLER AND
SLIGHTLY LESS HUMID CONDITIONS. EXPECT MINS TO FALL INTO THE
LOWER/MID 50S IN VALLEY REGIONS...AND 45-50 ACROSS HIGHER
ELEVATIONS...AS WELL AS PORTIONS OF THE UPPER HUDSON RIVER VALLEY.
THU-THU NT...A WEAK SHORTWAVE TROUGH WILL BRUSH NORTHERN AREAS
DURING THE MORNING HOURS...ACCOMPANIED BY SOME CLOUDS...AND
PERHAPS A COUPLE OF PASSING SHOWERS. OTHERWISE...EXPECT MAINLY
SUNNY CONDITIONS...ALONG WITH COOLER AND LESS HUMID CONDITIONS.
HAVE SIDED CLOSE TO THE WARMER MAV MOS FOR TEMPS...BASED ON RECENT
PERFORMANCE...WITH FORECAST MAXES IN THE MID/UPPER 70S IN
VALLEYS...AND 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FOR THU
NT...EXPECT CLEAR SKIES TO START...FOLLOWED BY SOME INCREASING
CLOUDS LATE...ESP ACROSS S/W AREAS. IT SHOULD BE RATHER COOL AND
COMFORTABLE...WITH MINS FALLING INTO THE UPPER 40S TO LOWER 50S IN
VALLEYS...AND PERHAPS SOME LOWER 40S ACROSS HIGHER ELEVATIONS
WITHIN THE NORTH COUNTRY AND WESTERN NEW ENGLAND.
FRI-FRI NT...MODELS ARE FAIRLY CONSISTENT WITH THE OVERALL
SYNOPTIC SITUATION...WITH A RATHER STRONG LOW PRESSURE SYSTEM
TRACKING THROUGH THE OHIO VALLEY TOWARD THE CENTRAL OR EASTERN
GREAT LAKES...AND A WARM/OCCLUDED FRONT APPROACHING OUR REGION FROM
THE SOUTHWEST. HOWEVER...TIMING DIFFERENCE STILL EXIST...WITH THE
00Z/30 NAM AND ECMWF BRINGING PRECIP FASTER INTO THE REGION FOR FRI
AFTERNOON...WHILE THE GFS/GEM HOLD IT OFF LONGER...UNTIL FRI EVE.
THE NAM SEEMS MOST AGGRESSIVE...WITH A PERIOD OF MODERATE RAIN OR
SHOWERS OCCURRING ACROSS PORTIONS OF THE MOHAWK VALLEY AS EARLY AS
FRI AFTERNOON...IN ASSOCIATION WITH STRONG MID LEVEL
FRONTOGENETICAL FORCING. AT THIS TIME...NOT COMPLETELY SOLD ON
THIS...BUT ACKNOWLEDGE THAT SOME RAIN COULD BREAK OUT IN PORTIONS
OF THE REGION FRI AFTERNOON...WITH CHC POPS AFTER A DRY FRI
MORNING. THEN...LIKELY POPS ALL AREAS FOR FRI NT AS A SOAKING RAIN
OCCURS. FOR TEMPS...SIDED A BIT CLOSER TO THE WARMER MAV MOS FOR
FRI...ASSUMING SOME SUNSHINE OCCURS IN THE MORNING...AND RAIN
HOLDS OFF LONG ENOUGH TO ALLOW TEMPS TO REACH THE UPPER 60S TO
LOWER TO MID 70S. HOWEVER...SHOULD MODERATE RAIN DEVELOP AS
QUICKLY AS THE NAM SUGGESTS...MUCH COOLER MAXES WOULD BE POSSIBLE.
FOR FRI NT...EXPECT MINS TO FALL INTO THE LOWER/MID 50S IN
VALLEYS...AND 45-50 ACROSS HIGHER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A BLEND OF THE GFS/ECMWF/HPC GUIDANCE WAS UTILIZED WHICH POINTS
TOWARD A PATTERN CHANGE FOR THIS FIRST WEEKEND OF JUNE.
A RATHER STRONG COLD FRONT IS POISED TO BE EAST OF THE HUDSON RIVER
SATURDAY MORNING TAKING ITS ASSOCIATED RAINFALL/SHOWERS INTO NEW
ENGLAND AND FURTHER EASTWARD. IN ITS WAKE...A COOL AND MOIST
CYCLONIC FLOW EVOLVES AS A VERTICALLY STACKED LOW BECOMES
QUASI-STATIONARY OVER LOWER ONTARIO AND QUEBEC PROVENCE THIS
WEEKEND. WHILE TIMING OF INDIVIDUAL SHORT WAVES REMAINS IN
QUESTION...IT APPEARS DIURNALLY DRIVEN SHOWERS WILL BE THE RESULT.
THERE ARE ADDITIONAL TRENDS SEEN IN THE GUIDANCE THIS MORNING OF
THIS UPPER LOW REFORMING OVER THE GULF OF MAINE WHICH WOULD KEEP THE
COOL AND MOIST CYCLONIC FLOW /ALONG WITH ATLANTIC MOIST CONVEYOR
BELT/ INTO THE BEGINNING OF NEXT WEEK.
THIS WILL KEEP TEMPERATURES AT OR BELOW NORMAL THROUGH MOST OF THE
LONG TERM PERIOD WITH PRECIPITATION AT OR ABOVE NORMAL.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
WIDELY SCATTERED SHOWERS MAY DRIFT ACROSS THE REGION THE REMAINDER
OF THE OVERNIGHT PERIOD. SHOWER POTENTIAL ALONG WITH WET GROUND AND
PARTIAL CLEARING...MVFR ARE EXPECTED WITH IFR POSSIBLE ESPECIALLY AT
KGFL/KPSF. AN IMPROVEMENT TO VFR EXPECTED AFTER SUNRISE WITH VFR
PERSISTING THROUGH THE MORNING. SOME AFTERNOON SHOWERS WITH AN
ISOLATED THUNDERSTORM POSSIBLE ON WEDNESDAY AFTERNOON AND WE WILL
PLACE A VCSH.
SOUTHWESTERLY WINDS WILL SHIFT TO WESTERLY OVERNIGHT AND THEN
WEST-NORTHWESTERLY WITH THE PASSAGE OF THE COLD FRONT LATER
WEDNESDAY.
OUTLOOK...
WED NT...IMPROVING TO VFR. SLIGHT CHC SHRA/TSRA EARLY.
THU-FRI...VFR...NO SIG WX.
FRI NT...VFR/MVFR. CHC SHRAS WITH IFR CONDITIONS.
SAT-SUN...VFR/MVFR. CHC -SHRAS
&&
.FIRE WEATHER...
A SECONDARY COLD FRONT WILL APPROACH FROM THE WEST LATE THIS
AFTERNOON...TRIGGERING ISOLATATED TO SCATTERED SHOWERS...AND
PERHAPS A THUNDERSTORM FOR AREAS MAINLY NEAR AND SOUTH OF ALBANY.
FAIR AND COOLER CONDITIONS WILL DEVELOP AS HIGH PRESSURE BUILDS
INTO THE REGION FOR TONIGHT INTO THURSDAY.
THE RH WILL FALL INTO THE 35-45 PERCENT RANGE THIS
AFTERNOON...THEN RECOVER TO 80-100 PERCENT TONIGHT WITH AREAS OF
DEW FORMATION LIKELY. THE RH WILL THEN FALL INTO THE 30-40 PERCENT
RANGE FOR THU AFTERNOON.
WINDS WILL BECOME SOUTHWEST TO WEST AT 10-20 MPH THIS
AFTERNOON...THEN WILL BECOME NORTHWEST AT LESS THAN 5 MPH
TONIGHT. ON THURSDAY...EXPECT WEST TO NORTHWEST WINDS TO INCREASE
TO 15-25 MPH.
&&
.HYDROLOGY...
NUMEROUS SHOWERS AND THUNDERSTORMS TUESDAY LED TO SOME RIVER
RISES...ESPECIALLY WITHIN PORTIONS OF THE WESTERN MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...AND SOUTHERN VT...WHERE RISES OF
2-3 FT OCCURRED. THESE RIVER LEVELS HAVE ALREADY STARTED DROPPING.
ISOLATED TO SCATTERED SHOWERS/TSTMS ARE POSSIBLE THIS AFTERNOON
AND EVENING...WITH POINT RAINFALL AMOUNTS GENERALLY REMAINING
UNDER ONE QUARTER OF AN INCH. THIS SHOULD CAUSE MINIMAL RIVER
RESPONSES.
A WIDESPREAD RAINFALL IS EXPECTED LATE FRIDAY INTO EARLY
SATURDAY...WITH RAINFALL AMOUNTS OF 0.50-1 INCH POSSIBLE. THIS MAY
CAUSE ADDITIONAL WITHIN BANK RISES ON AREA RIVERS/STREAMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/IAA
NEAR TERM...KL
SHORT TERM...KL
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...KL
HYDROLOGY...KL/IAA/11
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
725 PM EDT THU MAY 31 2012
.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM WILL TRACK ACROSS THE OHIO VALLEY AND
INTO THE EASTERN GREAT LAKES FRIDAY INTO SATURDAY, DRAGGING A COLD
FRONT ACROSS THE AREA FRIDAY NIGHT. WEAK HIGH PRESSURE WILL TRY TO
BUILD IN FROM THE SOUTH FOR SATURDAY INTO EARLY SUNDAY BEFORE LOW
PRESSURE TO OUR EAST DEEPENS AND SENDS WEAK DISTURBANCES TOWARD OUR
AREA THROUGH TUESDAY. ANOTHER AREA OF LOW PRESSURE TRACKING ACROSS
THE UPPER PLAINS WILL MOVE ACROSS THE OHIO AND TENNESSEE VALLEYS
MONDAY AND TUESDAY BUT WILL LIKELY REMAIN TO OUR SOUTH AS IT IS
SUPPRESSED BY THE LOW OFF THE NEW ENGLAND COAST.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
NO BIG CHANGES WITH THIS ESTF UPDATE. WE DID USE A COMBINATION OF
THE HIRES WRF-ARW AND WRF-NMM TO ADJUST THE SLOW PROGRESSION OF
THE SEA BREEZE INLAND. BASED ON CURRENT PERFORMANCE (AND HOPEFULLY
FUTURE TRENDS) THEY WERE HANDLING IT BETTER THAN THE RAP OR HRRR.
OTHER THAN SOME INCREASE IN HIGH CLOUDINESS OVERNIGHT AS THE MID
LEVEL RIDGE AXIS ARRIVES, WE SHOULD HAVE FAIR WEATHER IN THE NEAR
TERM. WINDS WILL GO LIGHT FOR MOST OF THE NIGHT, BUT EASTERLY
WINDS MAY BEGIN TO PICK UP JUST PRIOR TO DAYBREAK. TEMPERATURES
WERE A BLEND OF GUIDANCE AND CONTINUITY. DEW POINTS OVER MOST
LOCATIONS HAD DROPPED LATE THIS AFTERNOON AND THERE MAY BE SOME
RADIATING THIS EVENING, BUT THE GROUND IS GETTING WARM AND THE
NIGHTS ARE RATHER SHORT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
A WARM FRONT WILL TRY TO PUSH ACROSS THE AREA ON FRIDAY WHILE A COLD
FRONT APPROACHES FROM THE WEST. THERE IS SOME ISENTROPIC LIFT AHEAD
OF THE WARM FRONT, ALTHOUGH SATURATION TAKES A WHILE TO OCCUR. THE
MID LEVEL TROUGH AXIS MOVING INTO THE UPPER OHIO RIVER VALLEY, THE
TRIPLE POINT MOVING INTO CENTRAL PA AND THE APPROACHING COLD FRONT
LOOK MORE LIKE THE CUES FOR SIGNIFICANT RAINFALL. MOISTURE WILL BE
ON THE INCREASE THROUGH THE AFTERNOON, AND WE SEE AN APPROACHING
UPPER JET, SOME GOOD MID LEVEL Q-VECTOR CONVERGENCE, LOWER LEVEL
FRONTOGENESIS, AND DIFFERENTIAL DIVERGENCE BEGINNING TO COME
TOGETHER VERY NEAR US. INSTABILITY INVADES BEHIND THE WARM FRONT,
AND THAT LIKELY FAVORS SOUTHERN AND WESTERN PARTS OF OUR AREA. THERE
IS VERY GOOD BULK SHEAR AS ONE APPROACHES THE TRIPLE POINT. WE HAVE
NO ENHANCED WORDING THROUGH THE SHORT TERM, BUT STRONG STORMS
CERTAINLY MAY BE APPROACHING OUR WESTERN ZONES BY LATE FRIDAY
AFTERNOON. OUR POPS BY THE END OF THE DAY RANGE FROM LIKELY WEST TO
SLIGHT CHANCE OFF THE COAST. TEMPERATURES ARE VERY CLOSE TO
CONTINUITY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A COLD FRONT WILL MOVE THROUGH THE REGION ON FRIDAY NIGHT AS THE
STRONG PARENT LOW PRESSURE SYSTEM MOVES INTO SOUTHEASTERN CANADA AND
MOVES VERY LITTLE THROUGH EARLY SUNDAY. SURFACE LOW PRESSURE
DEVELOPS ALONG A BOUNDARY JUST TO OUR NORTH AND MOVES OVER THE NEW
ENGLAND COAST WHILE SLOWLY DRIFTING EASTWARD. A WEAK AREA OF HIGH
PRESSURE WILL TRY TO BUILD IN FROM THE SOUTH FOR SATURDAY AND EARLY
SUNDAY. THE SOUTHEASTERN CANADIAN LOW WILL THEN BEGIN TO MOVE
SOUTHEAST ON SUNDAY AND EVENTUALLY ABSORB THE NEW ENGLAND COASTAL
LOW. THIS MOVEMENT WILL THEN DRAG A BOUNDARY ACROSS THE AREA ON
SUNDAY NIGHT. THE LOW SEEMS TO SET UP SHOP OFF THE NEW ENGLAND COAST
THROUGH ABOUT TUESDAY. ENERGY ROTATING AROUND THIS CLOSED LOW WILL
BRING UNSETTLED WEATHER ACROSS OUR AREA THROUGH ABOUT MIDWEEK.
ANOTHER AREA OF LOW PRESSURE TRACKING ACROSS THE UPPER PLAINS WILL
MOVE ACROSS THE OHIO AND TENNESSEE VALLEYS MONDAY AND TUESDAY BUT
WILL LIKELY REMAIN TO OUR SOUTH AS IT IS SUPPRESSED BY THE LOW OFF
THE NEW ENGLAND COAST. THE STRONGER SURFACE LOW TO OUR NORTHEAST
FINALLY STARTS TO MOVE EASTWARD ON WEDNESDAY. THE UPPER LEVEL LOW
SLOWLY MOVES TO EAST BUT REMAINS NEARBY THROUGH THE END OF NEXT
WEEK.
FOR FRIDAY NIGHT WE MAY SEE HEAVY RAIN AND GUSTY WINDS AS
THUNDERSTORMS MOVE THROUGH AHEAD OF AND ALONG THE FRONTAL PASSAGE.
AREAS THAT HAVE SEEN COPIOUS AMOUNTS OF RAIN OVER THE PAST WEEK MAY
SEE SOME MORE AS PRECIPITABLE WATER VALUES REMAIN FAIRLY HIGH. THIS
MAY CONTRIBUTE TO LOCALIZED FLOODING ISSUES SO EXERCISE CAUTION IF
OUT WHEN STORMS MOVE THROUGH. WE WILL CONTINUE TO MONITOR THE HEAVY
RAINFALL THREAT.
AN UNSETTLED PERIOD OF WEATHER IS EXPECTED THROUGH THE EXTENDED AND
WITH THE EXCEPTION OF SATURDAY, WE CANNOT RULE OUT THE POSSIBILITY
OF SHOWERS AND/OR THUNDERSTORMS TO OCCUR. CONFIDENCE IS NOT
PARTICULARLY HIGH AT THIS POINT SO WE HAVE KEPT POPS MAINLY IN THE
CHC/SCHC RANGE.
OVERALL THOUGH, WE WILL SEE A COOLING TREND AS COOLER AIR GETS
PUSHED DOWN ACROSS THE REGION THROUGH THE PERIOD. WE WENT WITH A
BLEND OF HPC GUIDANCE AND CONTINUITY FOR TEMPERATURES THROUGH THE
PERIOD.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
INTO EARLY FRIDAY AFTERNOON WE CONTINUE THE VFR FORECAST. WE
EXPECT CONDITIONS TO DETERIORATE TOWARD PREVAILING MVFR LATE OR
JUST BEYOND THE CURRENT TAF FORECAST PERIOD. THE FORECAST TIME
GROUPS DURING VFR CONDITIONS WERE KEYED ON THE WIND. THUS THE
LOWER CLOUDS MAY ARRIVE A BIT FASTER WESTERN TERMINALS AND A BIT
SLOWER EASTERN TERMINALS.
THE SEA BREEZE FRONT OVER THE EASTERN COUNTIES (INCLUDING SUSSEX
DELAWARE) SHOULD DISSIPATE.
FOR THIS EVENING AND OVERNIGHT VFR CONDITIONS ARE EXPECTED WITH
LIGHT WINDS AND JUST SOME CIRRUS AROUND. WE DO NOT THINK THERE
WILL BE ENOUGH TIME COUPLED WITH THE THURSDAY AFTN DROP IN DEW
POINTS FOR FOG TO FORM.
ON FRIDAY MORNING, MID AND HIGH LEVEL CLOUDS SHOULD CONTINUE TO
MOVE INTO THE AREA AND WE EXPECT EAST TO SOUTHEAST WINDS TO START
AND INCREASE DURING THE MORNING WITH GUSTINESS OCCURRING BY NOON.
DURING THE AFTERNOON WITH EITHER A CUMULUS LEVEL OR ALTOCUMULUS
LEVEL CIG, WINDS SHOULD INCREASE FURTHER FROM THE SOUTHEAST WITH
GUSTINESS AVERAGING AROUND 25 KTS. WE BROUGHT IN THE MENTION OF
SHOWERS TO KABE AND TSRAS WITH MVFR CONDITIONS TO KRDG BEFORE THE
END OF THE TAF PERIOD. WE ARE VERY CONFIDENT ABOUT THE DETAILS, A
LITTLE LESS CONFIDENT ABOUT THE TIMING. WE ALSO SHOWED THESE
CONDITIONS ARRIVING AT KPHL DURING FRIDAY EVENING.
OUTLOOK...
FRIDAY NIGHT...SHOWERS AND THUNDERSTORMS DURING THE EVENING AND
OVERNIGHT HOURS WILL CAUSE CONDITIONS TO DETERIORATE TO MVFR/IFR.
THERE IS ALSO THE POTENTIAL FOR LOCAL DOWNPOURS AND GUSTY WINDS.
SOUTHEAST WINDS AROUND 10 TO 15 KNOTS WILL TURN TO THE SOUTH AND
THEN SOUTHWEST DURING THE LATE EVENING BEFORE SHIFTING TO WEST
TOWARD MORNING.
SATURDAY...BECOMING VFR BY EARLY SATURDAY MORNING WITH WEST WINDS 10
TO 15 KNOTS. WINDS MAY BECOME GUSTY DURING THE DAY.
SUNDAY...VFR CONDITIONS WITH WEST WINDS AROUND 10 KNOTS. SHOWERS ARE
POSSIBLE LATER IN THE DAY AND COULD CAUSE WHICH COULD CAUSE LOWER
VISIBILITIES AND/OR CEILINGS TO OCCUR.
MONDAY...VFR WITH A WEST TO NORTHWEST WIND AROUND 10 KNOTS.
AFTERNOON SHOWERS AND THUNDERSTORMS ARE POSSIBLE WHICH COULD CAUSE
LOWER VISIBILITIES AND/OR CEILINGS TO OCCUR.
TUESDAY...MAINLY VFR CONDITIONS EXPECTED WITH SHOWERS AND POSSIBLY A
THUNDERSTORM POSSIBLE, MAINLY TOWARD THE AFTERNOON HOURS. NORTH TO
NORTHEAST WINDS AROUND 10 KNOTS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS ARE FORECAST UNTIL THE EARLY EVENING ON
FRIDAY. TONIGHT SHOULD SEE LIGHT WINDS DEVELOPING AN EASTERLY
COMPONENT AND THEN INCREASING BY DAYBREAK. SEAS SHOULD REMAIN AT OR
BELOW 3 FT. THEN, EAST TO SOUTHEAST WINDS WILL CONTINUE TO INCREASE
DURING THE DAY ON FRIDAY UNTIL GUSTS TO 25 KT AND SEAS OF 5 FT
DEVELOP LATE.
OUTLOOK...
A STRONG COLD FRONT WILL CROSS THE AREA WATERS ON FRIDAY NIGHT
ACCOMPANIED BY STRONG GUSTY WINDS, RAIN AND POSSIBLY SOME
THUNDERSTORMS. ALTHOUGH AN INVERSION IS PRESENT ON MODEL SOUNDINGS,
THERE APPEARS TO BE A STRONG ENOUGH FLOW TO SUSTAIN SMALL CRAFT
ADVISORY GUSTS. THE STRONG SOUTH TO SOUTHEASTERLY FLOW AHEAD OF THE
FRONT WILL BRING GUSTS AROUND 25-30 KNOTS ALONG THE OCEAN AND 20-25
KNOTS IN THE DELAWARE BAY. SOME ENHANCEMENT ACROSS THE MOUTH OF THE
DELAWARE BAY COULD ALSO INCREASE GUSTS FOR A PERIOD AS WELL AHEAD OF
THE FRONT. SEAS ALSO BEGIN TO INCREASE IN THE SOUTHERLY FLOW AND
COULD REACH 5 FEET BY FRIDAY NIGHT. AS A RESULT, WE HAVE ISSUED A
SMALL CRAFT ADVISORY ON THE OCEAN FRONT FROM 6PM FRIDAY THROUGH 2PM
SATURDAY. A SMALL CRAFT FOR THE DELAWARE BAY WILL RUN FROM 6PM
FRIDAY THROUGH 10AM SATURDAY.
AS THE FRONT MOVES THROUGH THE WINDS TURN TO THE SOUTH THEN
SOUTHWEST AND EVENTUALLY BECOME MORE WESTERLY BY SATURDAY MORNING.
WINDS WILL THEN REMAIN WESTERLY THROUGH THE WEEKEND AND INTO THE NEW
WEEK. SEAS AND WINDS SUBSIDE ON SATURDAY AND WE DO NOT ANTICIPATE
THE NEED FOR ANY SMALL CRAFT ADVISORY HEADLINES FROM SATURDAY
THROUGH THE START OF THE NEW WEEK.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES OF APPROXIMATELY THREE-QUARTERS OF A FOOT ARE NECESSARY
TO BEGIN MINOR TIDAL FLOODING ALONG OUR ATLANTIC COASTLINE, RARITAN
BAY, DELAWARE BAY AND THE TIDAL DELAWARE RIVER WITH THE HIGHER HIGH
TIDE FROM EARLY FRIDAY EVENING THROUGH MIDNIGHT. THE INCREASE IN
EASTERLY WINDS COULD MAKE IT HAPPEN, AND WE WILL MENTION THE
POSSIBILITY OF MINOR TIDAL FLOODING OVER THOSE SHORELINES IN THE
HWO.
THE MARYLAND EASTERN SHORE WOULD NEED DEPARTURES IN EXCESS OF ONE
FOOT, AND WE PRESENTLY DON`T ANTICIPATE ANY PROBLEMS THERE.
THE NEXT TIME FRAME OF CONCERN IS THE SUNDAY THROUGH TUESDAY HIGH
TIDE CYCLES. WITH THE FULL MOON EXPECTED ON MONDAY AND HIGHER
ASTRONOMICAL TIDES, LOCATIONS ALONG OUR ATLANTIC COASTLINE, RARITAN
BAY, DELAWARE BAY AND THE TIDAL DELAWARE RIVER MAY EXPERIENCE
MINOR TIDAL FLOODING. ASTRONOMICAL HIGH TIDES ARE ONLY RUNNING
0.2-0.4 TENTHS BELOW MINOR COASTAL FLOODING THRESHOLDS SO WE WILL
KEEP AN EYE ON THIS OVER THE NEXT FEW DAYS. ONE ITEM IN OUR FAVOR
APPEARS TO BE AN OFFSHORE FLOW, WHICH WILL HELP TO LIMIT POTENTIAL
FOR FLOODING.
AGAIN, WITH DEPARTURES AROUND ONE FOOT, NO PROBLEMS ARE
ANTICIPATED ALONG THE EASTERN SHORE OF MARYLAND ON THE CHESAPEAKE
BAY AT THIS TIME.
&&
.RIP CURRENTS...
WITH A FORECAST INCREASE OF SOUTHEAST WINDS DURING THE AFTERNOON
ON FRIDAY AND WITH US GETTING CLOSER TO THE FULL MOON, OUR IN HOUSE
PROCEDURE TAKES NEW JERSEY INTO A MODERATE RISK OF RIP CURRENTS AND
PLACES DELAWARE BEACHES JUST SHORT. WITH THE WINDS EXPECTED TO
INCREASE IN DELAWARE FIRST, WE DECIDED TO OUTLOOK ALL AREAS FOR A
MODERATE RISK ON FRIDAY. PLEASE LOOK FOR UPDATED INFORMATION ON
FRIDAY MORNING.
&&
.CLIMATE...
IN SPITE OF ANOTHER LA NINA WINTER AND A MILD ONE AT THAT, BOTH
APRIL AND MAY WERE UNSEASONABLY WARM AGAIN FOR THE FOURTH
CONSECUTIVE SPRING. SINCE 1872, THIS COMBINATION HAS OCCURRED ONLY
TWENTY-ONE TIMES, BUT NOW NINE TIMES SINCE 1990. WE HAVE ALSO HAVE HAD
NINE CONSECUTIVE MONTHS OF ABOVE NORMAL TEMPERATURES. BY OUR
CATEGORY DEFINITION UNSEASONABLY COOL/NORMAL/UNSEASONABLY WARM MONTHS
ARE DIVIDED INTO THIRDS. THIS IS ONLY THE 5TH TIME THIS HAS OCCURRED
AFTER A LA NINA WINTER AND GIVES US A LONE FOURSOME OF ANALOGS FOR
THIS UPCOMING SUMMER. THE SUMMER OF 1985 WAS THE LONE COOL ONE IN
THE FOURSOME AND HAS WEIGHED DOWN THE ANALOG AVERAGE. WE`LL FIND OUT
ON SEPTEMBER 1ST IF THIS WAS A GOOD OR BAD INCLUSION. THE OTHER
THREE SUMMERS WERE WARMER THAN NORMAL EVEN USING THE CURRENT
1981-2010 NORMALS. THAT THREESOME AVERAGE WAS 77.0 DEGREES. WE ARE
CERTAIN SOMEONE WILL NOTICE THAT ALL OF THESE ANALOG SUMMERS SAW
TROPICAL ACTIVITY THAT AFFECTED OUR AREA: CONNIE AND DIANE IN 1955,
GLORIA IN 1985, ALLISON IN 2001 AND IRENE IN 2011. WITH THREE OF
THEM OCCURRING IN AUGUST, THEY SKEWED THE SUMMER PRECIPITATION
AVERAGE TO WET. THE PRECIPITATION ASSOCIATED WITH ALLISON WAS NOT
ENOUGH TO OFFSET A VERY DRY JULY AND AUGUST.
YEAR JUNE AVG JULY AVG AUGUST AVG SUMMER AVG SUMMER PCPN
1955 69.2 81.4 78.1 76.2 14.80
1985 68.8 75.4 74.1 72.8 9.36
2001 75.2 75.4 79.9 76.8 8.20
2011 75.4 82.4 76.1 78.0 22.02
AVG 72.2 78.7 77.1 76.0 13.60
1981-2010 NML 73.3 78.1 76.6 76.0 11.28
THE OFFICIAL CPC OUTLOOK FOR THIS SUMMER IS FOR A GREATER CHANCE OF
IT BEING WARMER THAN NORMAL IN THE SOUTHERN PART OF OUR CWA AND
EQUAL CHANCES OF IT BEING EITHER WARMER OR COOLER THAN NORMAL IN THE
NORTHERN PART OF OUR CWA. THE PRECIPITATION OUTLOOK IS FOR EQUAL
CHANCES OF IT BEING EITHER DRIER OR WETTER THAN NORMAL.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM FRIDAY TO 2 PM EDT SATURDAY FOR
ANZ450>455.
SMALL CRAFT ADVISORY FROM 6 PM FRIDAY TO 10 AM EDT SATURDAY
FOR ANZ430-431.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...DELISI
SHORT TERM...DELISI
LONG TERM...MEOLA
AVIATION...GIGI/MEOLA
MARINE...DELISI/MEOLA
TIDES/COASTAL FLOODING...DELISI/MEOLA
RIP CURRENTS...GIGI
CLIMATE...GIGI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
318 AM EDT WED MAY 30 2012
.SYNOPSIS...
A COLD FRONT WILL EASE OFF THE COAST THROUGH THIS MORNING, THEN AN
AREA OF LOW PRESSURE WILL TRACK NORTHEASTWARD ALONG IT AND REMAIN
SOUTH AND EAST OF OUR REGION INTO THURSDAY. HIGH PRESSURE BUILDS IN
LATER TONIGHT INTO FRIDAY MORNING BEFORE SHIFTING OFFSHORE. AN AREA
OF LOW PRESSURE MOVING THROUGH THE OHIO VALLEY AND GREAT LAKES
REGIONS SATURDAY WILL TRACK TO OUR NORTHWEST. ITS ASSOCIATED COLD
FRONT IS FORECAST TO MOVE THROUGH OUR AREA SATURDAY. HIGH PRESSURE
THEN BUILDS TO OUR SOUTH SUNDAY AND MONDAY, WITH THE NEXT COLD FRONT
APPROACHING LATER TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE FORECAST PROBLEMS FOR TODAY INCLUDE CLOUD COVER...EXTENT OF
PRECIPITATION ACROSS THE SOUTH THIS MORNING) AND INTO THIS
AFTERNOON?)...AS WELL AS THE POTENTIAL FOR LOW TOPPED CONVECTION
NORTH AND WEST THIS AFTERNOON AND EVENING.
THE MAIN AREA OF PRECIPITATION THIS MORNING (APPROACHING THE LEHIGH
VALLEY AND SOUTHERN POCONOS) IS BEING DRIVEN BY A WEAK MID LEVEL
SHORT WAVE. THE AIRMASS IS STILL MARGINALLY UNSTABLE...SO THERE
COULD EVEN BE A FEW LIGHTNING STRIKES EARLY. THE LATEST HRRR RUN
SHOWS THIS AREA SLOWLY DECREASING IN SIZE AT IT HEADS FRO NORTHEAST
NEW JERSEY BEFORE DAYBREAK. THIS SEEMS REASONABLE...AND WILL BE
ACCOUNTED FOR IN THE EARLY MORNING FORECAST.
SCATTERED CONVECTION CONTINUES TO FIRE AND MOVE NORTHEAST IN THE
DEEP SOUTHWEST MID LEVEL FLOW ACROSS THE REMAINDER OF THE REGION.
SINCE THE AIRMASS IS MARGINALLY UNSTABLE..AND ACTIVITY CONTINUES TO
TRACK NORTHEAST FROM CENTRAL VIRGINIA...THIS ACTIVITY SHOULD PERSIST
PAST DAYBREAK. THERE HAS NOT BEEN MUCH LIGHTNING WITH THIS BATCH OF
SHOWERS...AND THE 0000 UTC RNK SOUNDING SUGGESTS THAT THESE SHOWERS
ARE MORE OF A BYPRODUCT OF WARM CONVECTIVE PROCESSES.
THE ACTIVITY ACROSS THE NORTHEAST SHOULD BE GONE BEFORE 1200 UTC.
THE SHOWERS TO THE SOUTHEAST MAY TAKE QUITE A BIT LONGER. THE
SHOWERS LIE IN A BELT OF STILL MOISTURE RICH ENVIRONMENT (WHERE
PRECIPITABLE WATER VALUES WILL REMAIN ABOVE 1.50 INCHES FOR MUCH OF
THE DAY). THIS BELT OF MOISTURE SHOULD REMAIN MARGINALLY UNSTABLE
INTO EARLY THIS AFTERNOON...SO THE WARM PROCESS CONVECTION SHOULD
CONTINUE.
THE NORTHWEST EXTENT OF THE ACTIVITY IS IN SOME DOUBT...BUT FOR NOW
THE MAIN BATCH OF SHOWERS LOOKS TO AFFECT MAINLY DELAWARE AND
SOUTHEAST NEW JERSEY. WITH THAT...THE HIGHEST SHOWER CHANCES WILL BE
PLACES THERE. SINCE THE AIRMASS IS MOISTURE LADEN AND MARGINALLY
UNSTABLE...LOCALLY HEAVY RAIN IS POSSIBLE THIS MORNING IN THE
ABOVE MENTIONED AREAS. HOWEVER...THE ACTIVITY WILL MOVE THROUGH AN
AREA THAT CAN ABSORB THE RAIN (MAINLY SANDY SOIL)...SO NO HYDROLOGY
HEADLINES ARE NEEDED.
FURTHER NORTHWEST...MID LEVEL CLOUDINESS SHOULD CLEAR FROM WEST TO
EAST THIS MORNING INTO EARLY THIS AFTERNOON. THE CLOUDINESS WILL CUT
DOWN ON THE AMOUNT OF HEATING THIS MORNING...KEEPING TEMPERATURES 5
TO 10 DEGREES COOLER THAN TUESDAY. THE NAM MOS MAY BE A BIT ON THE
HIGH SIDE...SO FOR NOW HIGHS WERE BASED ON THE MOS BLEND.
THE COLD FRONT APPROACHING FROM THE WEST LATE THIS AFTERNOON SHOULD
HAVE MARGINAL INSTABILITY ASSOCIATED WITH IT. HOWEVER...MOISTURE
COULD BE THE LIMITING FACTOR FOR CONVECTION...AS SURFACE DEW POINTS
DROP OFF AND PRECIPITABLE WATER VALUES DROP BACK CLOSER TO AN INCH.
MODIFIED SOUNDINGS ACROSS THE LEHIGH VALLEY...SOUTHERN POCONOS AND
NORTHWEST NEW JERSEY SHOW MEAN LAYER CAPE VALUES NEAR 250 J/KG...SO
THERE IS SOME LIMITED CONVECTIVE POTENTIAL.
THE MODIFIED SOUNDINGS SHOW A LONG THIN CAPE PROFILE...INDICATIVE OF
SHORT LIVED UPDRAFTS. ANY STRONGER STORM COULD PRODUCE GUSTY WINDS
(DUE TO DRYING IN THE MID LEVELS) AND PERHAPS MALL HAIL (WHICH CAPE
IN THE HAIL GROWTH REGION)...BUT THE POTENTIAL DOES NOT MERIT A
MENTION IN THE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
ANY LEFTOVER CONVECTION COULD SURVIVE INTO THE EVENING HOURS...AS
THE LAST OF THE MARGINAL INSTABILITY WANES. THIS APPEARS MOST LIKELY
ACROSS THE SOUTHERN POCONOS AND NORTHWEST NEW JERSEY. OTHERWISE...
THE MID LEVEL CLOUDINESS SHOULD DISSIPATE AS DRIER AIR ARRIVES FROM
THE WEST.
THE LOW LEVEL FLOW IS NOT STRONG BEHIND THE FRONT...AND THIS SHOULD
RESULT IN A SLOW AIRMASS CHANGE. THE LIGHT WINDS AND MAINLY CLEAR
SKIES AFTER MIDNIGHT SHOULD RESULT IN PATCHY FOG...ESPECIALLY IN
PROTECTED LOCATIONS. FOR THE MOST PART...WITH THE AIRMASS CHANGE
ONLY PARTIALLY COMPLETE...LOWS WERE BASED ON THE WARMER NAM MOS
NUMBERS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE OVERALL SYNOPTIC PATTERN IS COMPRISED OF A TROUGH THAT AMPLIFIES
FROM THE MIDWEST AND GREAT LAKES INTO THE OHIO VALLEY THURSDAY AND
FRIDAY, THEN EVENTUALLY INTO THE NORTHEAST OVER THE WEEKEND. THIS
ENERGY MAY HANG BACK THOUGH FOR AWHILE AS IT CLOSES OFF INTO
SOUTHEASTERN CANADA. THIS MAIN TROUGH IS THEN FORECAST TO SHIFT TO
OUR EAST AS WE GO THROUGH EARLY NEXT WEEK WITH A RIDGE BUILDING
ACROSS THE MIDWEST AND TOWARD THE OHIO VALLEY. THERE IS SOME LOWER
CONFIDENCE THOUGH ESPECIALLY FRIDAY AND SATURDAY WITH THE TIMING OF
THE SYSTEM LIFTING TO OUR NORTHWEST AND ITS ASSOCIATED COLD FRONT.
FOR THURSDAY AND FRIDAY, TROPICAL CYCLONE BERYL OR ITS REMNANTS ARE
EXPECTED TO BE FAR ENOUGH EAST OF THE AREA THURSDAY THEN WEAK HIGH
PRESSURE ARRIVES FROM THE NORTHWEST. THIS WILL RESULT IN A NORTHWEST
BREEZE ALONG WITH DRIER AIR ACROSS THE REGION THURSDAY. THERE SHOULD
BE A DECENT AMOUNT OF SUNSHINE WITH ENOUGH SUBSIDENCE BETWEEN
SYSTEMS. AN AMPLIFYING TROUGH IN THE MIDWEST IS THEN FORECAST TO
SLIDE EASTWARD. THIS WILL DRIVE A SURFACE LOW UP THE OHIO VALLEY AND
INTO THE GREAT LAKES LATE THURSDAY AND FRIDAY WITH INCREASING WAA ON
THE EAST SIDE. THIS WILL ALSO ALLOW A SOUTHERLY FLOW TO INCREASE
SOME ALONG WITH A MOISTURE RETURN. AS A RESULT, SOME HIGH TO MID
LEVEL CLOUDS SHOULD BE ON THE INCREASE THURSDAY NIGHT WITH THESE
CLOUDS THICKENING UP DURING FRIDAY. GIVEN DECENT HEIGHT FALLS AND
INCREASING LOW-LEVEL MOISTURE, ENOUGH ASCENT SHOULD START TO
OVERSPREAD THE REGION TO RESULT IN SOME SHOWERS AND PERHAPS THUNDER
BY LATE AFTERNOON ESPECIALLY ACROSS THE WESTERN ZONES. A PLUME OF
DEEPER MOISTURE /PW VALUES INCREASE TO AROUND 1.5 INCHES/ ALONG WITH
STRONGER ASCENT ARRIVES FRIDAY NIGHT, THEREFORE A BAND OF SHOWERS
AND PERHAPS EMBEDDED THUNDER MOVES THROUGH. THIS IS WITHIN A THETA-E
RIDGE AHEAD OF THE COLD FRONT. WHILE SOME THUNDER CANNOT BE RULED,
WE HELD OFF ON A MENTION FOR NOW GIVEN SOME UNCERTAINTY REGARDING
THE INSTABILITY. WHILE LOCALLY HEAVY RAIN MAY OCCUR, THE ENTIRE
SYSTEM MAY BE MOVING ENOUGH TO NOT CAUSE MUCH IN THE WAY OF ANY
CONCERNS. WE PEAKED THE POPS IN THE LIKELY RANGE FRIDAY NIGHT.
FOR SATURDAY AND SUNDAY, IT APPEARS THE MAIN COLD FRONT MOVES
THROUGH DURING SATURDAY WITH SOME SHOWERS ESPECIALLY DURING THE
FIRST HALF OF THE DAY. WE LOWERED THE POPS THROUGH THE DAY, AND
THESE MIGHT BE ABLE TO BE LOWERED EVEN FASTER AS THE SYSTEM COULD BE
FAST ENOUGH TO SWEEP THE MAIN PLUME OF MOISTURE TO OUR EAST BY MID
TO LATE MORNING. THE MAIN UPPER-LEVEL TROUGH LOOKS TO SWING ACROSS
ON SUNDAY AND AN IMPULSE ROUNDING THE BASE OF THE TROUGH MAY ALLOW
FOR SOME SHOWERS OR A THUNDERSTORM. THIS MAY ALSO BE MARKED BY A
TROUGH AT THE SURFACE. AS OF NOW, THE COVERAGE LOOKS SMALL THEREFORE
WE KEPT THE POPS ON THE RATHER LOW SIDE. THE FLOW THEN TENDS TO TURN
MORE NORTHWESTERLY AS HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY
AND LOW PRESSURE IS TO OUR NORTHEAST.
FOR MONDAY AND TUESDAY, THE CYCLONIC FLOW SHOULD BE WEAKENING AS THE
MAIN TROUGH TO OUR NORTHEAST SLOWLY MIGRATES EASTWARD. HOWEVER, SOME
GUIDANCE TENDS TO CLOSE THIS FEATURE OFF AND THIS ALLOWS IT TO SIT
JUST OFF THE COAST OF NEW ENGLAND. THIS SCENARIO WOULD FAVOR A
TROUGH BECOMING ENHANCED IN THE NORTHEAST AND THE RIDGE INTO THE
OHIO VALLEY BEING PUSHED WESTWARD SOME. IF SOME SHORT WAVE ENERGY
INITIALLY TOPS THE RIDGE OR COMES AROUND THE BACKSIDE OF THE TROUGH
NEAR THE NEW ENGLAND COAST, SOME SHOWERS CANNOT BE RULED ESPECIALLY
TUESDAY. OUR CONFIDENCE THOUGH LOWERS HERE DUE TO MORE UNCERTAINTY
WITH THE DETAILS. THE NEXT FRONT APPROACHES THEN LATER TUESDAY,
ALTHOUGH THIS TIME MAY BE IMPACTED BY WHATEVER THE TROUGH OFF THE
NEW ENGLAND COAST ENDS UP DOING. FOR NOW, WE WENT WITH SLIGHT CHC TO
LOW CHC POPS DURING THIS TIME FRAME.
AS FOR TEMPERATURES, WE GENERALLY USED A MOS BLEND FOR THURSDAY
THROUGH FRIDAY, FOLLOWED BY A BLEND OF CONTINUITY AND MOSGUIDE.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
GENERALLY VFR CONDITIONS CONTINUE ACROSS THE AREA EARLY THIS
MORNING. A BATCH OF SHOWERS MOVING ACROSS NORTHEAST MARYLAND...
DELAWARE AND NEW JERSEY WILL RESULT IN MAINLY VFR CONDITIONS THROUGH
ABOUT 0900 UTC. AFTER THAT...THE MOIST LOW LEVEL COULD PRODUCE MVFR
CONDITIONS...MAINLY FOR VISIBILITY IN FOG (BUT CEILINGS MAY ALSO BE
MVFR FOR A TIME AT KACY).
FURTHER WEST...A BATCH OF SHOWERS AND A FEW THUNDERSTORMS MAY AFFECT
KRDG AND KABE THROUGH ABOUT 0900 UTC. RIGHT NOW...CONDITIONS ARE
EXPECTED TO DROP TO MVFR IN THE SHOWERS AND PATCHY FOG IN THESE
AREAS. AFTER 0900 UTC...AFTER THE SHOWERS HAVE EXITED...KRDG AND
KABE SHOULD DROP TO MVFR AND STAY THERE THROUGH 1300 UTC.
AFTER 1300 UTC...ALL AREAS SHOULD SEE CONDITIONS JUMP TO VFR. THE
WIND WILL BACK TO SOUTH AND REMAIN UNDER 10 KNOTS INTO MID
AFTERNOON. A FEW SHOWERS AND POSSIBLY A THUNDERSTORM COULD AFFECT
KRDG AND KABE AFTER 2000 UTC...THROUGH ABOUT 0000 UTC. THERE IS NOT
ENOUGH CONFIDENCE TO ADD THIS TO THE FORECAST YET.
VFR CONDITIONS ARE EXPECTED FOR THE FIRST PART OF THE NIGHT...AS A
COLD FRONT MOVES THROUGH THE REGION. A FEW PLACES...SUCH AS KRDG AND
KMIV...COULD SEE MVFR FOG DEVELOP AFTER 0600 UTC THURSDAY...AS THE
LOW LEVEL FLOW REMAINS LIGHT.
OUTLOOK...
THURSDAY...VFR WITH NORTHWESTERLY WIND GUSTS TO ABOUT 20 KNOTS.
FRIDAY...VFR DURING THE DAY, ALTHOUGH CLOUDS SHOULD BE ON THE
INCREASE. SUB-VFR ARRIVING AT NIGHT WITH SHOWERS MAYBE A
THUNDERSTORM. SOME OF THE SHOWERS MAY CONTAIN LOCALLY HEAVY RAIN.
SOUTHEASTERLY WINDS TO ABOUT 10 KNOTS.
SATURDAY...SUB-VFR CONDITIONS TO START WITH SHOWERS, THEN A COLD
FRONT MOVES THROUGH WITH IMPROVING CONDITIONS. SOUTH OR SOUTHEAST
WINDS WILL SHIFT TO THE WEST BEHIND THE COLD FRONT WITH PERHAPS
GUSTS UP TO 20 KNOTS.
SUNDAY...VFR WITH WEST/NORTHWEST WINDS IN THE 10 TO 15 KNOT RANGE.
&&
.MARINE...
WINDS AND SEAS DROPPED BELOW SMALL CRAFT LEVELS ACROSS ALL WATERS
EARLY THIS MORNING. THE BEST PRESSURE GRADIENT IS EAST OF THE
REGION...WITH A SLOW MOVING COLD FRONT APPROACHING FROM THE WEST.
THE SETUP SHOULD ENSURE THAT WINDS REMAIN BELOW SMALL CRAFT LEVELS
TODAY INTO THIS EVENING. THE SOUTH SOUTHEAST SWELL THIS MORNING...A
RESULT IN THE SOUTHERLY WINDS TUESDAY...SHOULD CONTINUE TO SLOWLY
SUBSIDE...AS THE SWELL SORTS ITSELF OUT.
THERE IS SOME MODEL SPREAD CONCERNING JUST HOW MUCH OF AN INFLUENCE
BERYL OR HERE EXTRATROPICAL PERSONA WILL HAVE ON THE SOUTHERN WATERS
LATER TONIGHT. THE GFS IS CLOSEST (AND HAS BEEN FOR A FEW MODEL RUNS
NOW) WITH THE WESTERN PERIPHERY OF THE GRADIENT. THIS IS IMPORTANT
BECAUSE THIS SOLUTION WOULD BEND WINDS BACK AROUND TO THE NORTHEAST
AND NORTH FASTER THAN OTHER MODELS. IT DOES NOT APPEAR TO ADD MUCH
MORE TO THE WIND SPEED THAN OTHER MODELS...THOUGH THE SOUTHERN OCEAN
WATERS AND THE LOWER DELAWARE BAY COULD SEE GUSTS TO 20 KNOTS BETWEEN
0600 UTC AND 1200 UTC THURSDAY. AT THIS POINT...WIND GUSTS ARE
EXPECTED TO REMAIN BELOW SMALL CRAFT LEVELS.
SEAS COULD BE ANOTHER MATTER. THE WNAWAVE (DRIVEN BY GFS WINDS)
SUGGEST THAT AS THE PERIOD GETS LONGER LATE TONIGHT...WAVE HEIGHTS
COULD APPROACH 5 FEET ON THE SOUTHERN OCEAN WATERS. CONFIDENCE IN
THIS OCCURRING IS FAIRLY LOW...SO SEAS WILL BE LEFT BELOW 5 FEET FOR
TONIGHT.
OUTLOOK...
THE CONDITIONS ARE ANTICIPATED TO BE BELOW SMALL CRAFT ADVISORY
CRITERIA OVERALL THURSDAY, ALTHOUGH TROPICAL CYCLONE BERYL OR ITS
REMNANTS TRACKING TO OUR SOUTH AND EAST MAY ALLOW FOR SOME INCREASE
IN THE SEAS FOR A TIME. HIGH PRESSURE BRIEFLY BUILDS IN LATER
THURSDAY INTO FRIDAY BEFORE SHIFTING OFFSHORE. THE NEXT SYSTEM
ARRIVES LATER FRIDAY WITH A SOUTHEAST TO SOUTH WIND OCCURRING. A
COLD FRONT MOVES THROUGH SATURDAY WITH A WIND SHIFT TO THE WEST AND
NORTHWEST. THE WINDS AND SEAS WILL INCREASE IN ADVANCE OF THIS
SYSTEM AND A SMALL CRAFT ADVISORY MAY BE NEEDED FOR A TIME. THE
WINDS BEHIND THIS SYSTEM DO NOT LOOK ALL THAT STRONG, THEN
WEST/NORTHWEST WINDS CONTINUE SUNDAY ALTHOUGH IT LOOKS TO BE AT OR
BELOW 20 KNOTS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...HAYES
SHORT TERM...HAYES
LONG TERM...GORSE
AVIATION...GORSE/HAYES
MARINE...GORSE/HAYES
AREA FORECAST DISCUSSION
NWS MIAMI FL
953 PM EDT THU MAY 31 2012
.UPDATE...NO CHANGES ARE PLANNED FOR THE EVENING UPDATES. A STEADY
STREAM OF RICH TROPICAL MOISTURE CONTINUES TO TRANSLATE NORTHWARD
FROM THE CARIBBEAN IN THE INCREASING SOUTHWEST FLOW ALOFT AHEAD OF
A DEEPENING MID LEVEL TROUGH OVER THE SOUTHEAST STATES. THIS ALSO
EVIDENT ON WATER VAPOR IAMGERY AND THE 00Z MFL SOUNDING. ALSO
EVIDENT ON WATER VAPOR IS A VORT MAX MOVING INTO THE SOUTHEAST GULF
AND THIS WILL ONLY ENHANCE CONVECTIVE ACTIVITY LATER TONIGHT INTO
EARLY FRIDAY. THE HRRR ALSO INDICATES CONVECTION TO CONTINUE
THROUGH THE NIGHT WITH A RAPID INCREASE AS THE TROUGH APPROACHES
ALONG THE SOUTHWEST COAST AFT 09Z.
KOB
&&
.PREV DISCUSSION... /ISSUED 639 PM EDT THU MAY 31 2012/
AVIATION...A VRY MOIST SW WND FLOW ALOFT WITH AN IMPULSE OF
INSTABILITY MOVG NE FM THE W CUBA/YUCATAN CHANNEL AREA WL LEAD
TO CLDY SKIES AND INCRG CHC OF RA/ISOLD TSRA MOVG ONTO THE W COAST
BUT MOST LIKELY NOT MAKING TO THE E COAST THRU 06Z. VFR XPCTD ALL
TERMINALS THRU 06Z XCPT PSBL MVFR CIG/VSBY AT KAPF BUT NOT DVLPG
E COAST TIL 12Z. AFT 12Z NMRS/WDSPRD RA WITH ISOLD TSRA PSBL WITH
WDSPRD MVFR CIG/VSBY PSBL. SFC WND DCRG TO LESS THAN 10 KTS BUT ON
E COAST SSE MOSTLY BUT LGT SSW FLOW PSBL 06Z TO 12Z WITH WNDS BCMG
SSE AND 10 TO 15 KTS. AT KAPF SW WND LESS THAN 10 KTS THRU 09Z
THEN BCMG SE-SSE WITH W COAST SEA BRZE AFT 16Z.
PREV DISCUSSION... /ISSUED 244 PM EDT THU MAY 31 2012/
SHORT TERM (TONIGHT-SATURDAY NIGHT)...
THE LATEST WATER VAPOR LOOP SHOWED BROAD CYCLONIC FLOW ACROSS THE
EASTERN HALF OF THE COUNTRY EXTENDING SOUTH ACROSS THE GULF OF
MEXICO WITH A FEW NOTABLE SHORTWAVE TROUGHS EMBEDDED AND PLENTY OF
MID/UPPER MOISTURE SPREADING NORTH OVER THE FLORIDA PENINSULA FROM
THE CARIBBEAN. THE LATEST MODEL GUIDANCE HAS INITIALIZED WELL WITH
THIS UPPER PATTERN AND SHOWS THE SHORTWAVE TROUGH CURRENTLY OVER OR
NEAR THE YUCATAN PENINSULA LIFTING NORTHEAST TONIGHT THEN ACROSS THE
LOCAL AREA FRIDAY AND FRIDAY NIGHT WITH DRY AIR GRADUALLY FILLING IN
THROUGH THE SATURDAY NIGHT. PLENTY OF DEEP LAYER MOISTURE LIFTING
NORTHEAST OUT OF THE CARIBBEAN ASSOCIATED WITH THIS UPPER FEATURE
WILL KEEP THE RAINFALL CHANCES ELEVATED ACROSS THE LOCAL AREA
THROUGH THIS TIME. THE LATEST MODEL PWAT VALUES REFLECT THIS AND
INCREASE INTO THE 2-2.5 INCH RANGE THROUGH THE DAY FRIDAY AS THIS
SURGE MOISTURE SPREADS NORTHEAST OVER THE AREA. A BLEND OF THE RAW
MODEL QPF AND GUIDANCE INDICATES ADDITIONAL RAINFALL
ACCUMULATIONS REACHING THE 2 TO 4 INCH RANGE ACROSS THE BULK OF THE
AREA THROUGH THIS TIME. THE LATEST HPC GUIDANCE ALSO INDICATES THESE
TOTALS AND KEEPS THE HIGHER END OF THIS RANGE OVER THE SOUTHERN HALF
OF THE LOCAL AREA OR SOUTH OF ALLIGATOR ALLEY. AS TYPICALLY OBSERVED
DURING THESE EVENTS...LOCALLY HIGHER AMOUNTS WILL CERTAINLY BECOME A
POSSIBILITY WHERE THE HEAVIER ACTIVITY BECOMES CONCENTRATED.
CONSIDERING THE RECENT RAINFALL ACTIVITY OVER THE PAST WEEK OR
TWO...INTERESTS ARE ENCOURAGED TO MONITOR LATER FORECASTS FOR
UPDATES THROUGH THIS TIME AS A FLOOD WATCH IS NOT OUT OF QUESTION.
SATURDAY AND SATURDAY NIGHT...DESPITE SOME MINOR TIMING DIFFERENCES
BETWEEN THE LATEST MODEL GUIDANCE...A GENERAL DRYING PATTERN WILL BE
ANTICIPATED AS THE UPPER TROUGH MOVES THROUGH FROM WEST TO EAST.
THIS DRY AIR COMBINED WITH SUBSIDENCE ON THE BACK SIDE OF THE TROUGH
SHOULD LEAD TO CLEARING CONDITIONS COME SATURDAY NIGHT.
HOWEVER...THE NAM IS QUITE A BIT SLOWER WITH THIS DRIER AIR
SPREADING EAST ACROSS THE AREA. CONSIDERING THE UNCERTAINTIES AT
THIS TIME...WE WILL NOT COMPLETELY RULE OUT THE POTENTIAL FOR
ADDITIONAL RAINFALL THROUGH THIS TIME AND CONTINUE TO MONITOR THE
EVOLUTION OF THIS SYSTEM.
LONG TERM (SUNDAY-WEDNESDAY)...
DRIER CONDITIONS WILL BE EXPECTED THROUGH THE BEGINNING OF THE
UPCOMING WEEK. HOWEVER...AFTERNOON SHOWERS/TSTMS WILL BE ANTICIPATED
EACH DAY. WITH THE MID/UPPER FLOW CONTINUING OUT OF THE WEST THE
BEST RAINFALL CHANCES SHOULD REMAIN OVER THE EASTERN AREAS.
MARINE...
LIGHT SOUTHERLY WINDS ARE EXPECTED EACH DAY THROUGH
FRIDAY...THEN INCREASING INTO THE MODERATE RANGE INTO SATURDAY
AS A FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST. SCATTERED TO
NUMEROUS SHOWERS WITH ISOLATED THUNDERSTORMS WILL CONTINUE INTO
SATURDAY...WHICH COULD LEAD TO PERIODS WITH GUSTY WINDS AND CHOPPIER
CONDITIONS IN AND AROUND ANY HEAVY SHOWER OR STORM THAT DEVELOPS.
DRIER CONDITIONS WITH LIGHT WEST NORTHWEST WINDS WILL BE EXPECTED IN
THE WAKE OF THIS SYSTEM SUNDAY INTO THE UPCOMING WEEK.
AVIATION...
SKIES WERE STARING TO CLEAR EARLY THIS AFTERNOON OVER
SOUTH FLORIDA. THIS WILL ALLOW FOR A SEA BREEZE TO SET UP OVER THE
EAST COAST METRO AREAS AND PUSH SLOWLY INLAND. SO WILL SHOW VRB 05
KTS UNTIL ABOUT 20Z THEN A 160 TO 170 DEGREE DIRECTION WITH SPEEDS
OF 5 TO 10 KNOTS. THE EAST COAST SEA BREEZE WILL ALSO ALLOW FOR
THUNDERSTORMS TO DEVELOP OVER THE INTERIOR AREAS AND PUSH BACK
TOWARD THE EAST COAST TAF SITES LATE THIS AFTERNOON. SO WILL PUT IN
A VCTS IN FOR THE EAST COAST TAF SITES FROM 20Z UNTIL 01Z.
TROPICAL MOISTURE WILL CONTINUE OVER SOUTH FLORIDA TONIGHT ALLOWING
FOR SCATTERED SHOWERS TO CONTINUE TONIGHT AT ALL OF THE TAF SITES.
SO WILL CONTINUE THE VCSH FOR ALL OF SOUTH FLORIDA TAF SITES FOR
TONIGHT.
THE CEILING AND VIS WILL ALSO REMAIN IN THE VFR CONDITIONS FOR ALL
OF SOUTH FLORIDA TAF SITES THIS AFTERNOON INTO TONIGHT...DUE TO THE
UNKNOWN TIMING OF THE SHOWER AND THUNDERSTORM ACTIVITY AFFECTING THE
TAF SITES.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 86 71 89 / 30 70 60 40
FORT LAUDERDALE 73 85 75 89 / 30 70 60 40
MIAMI 73 87 75 90 / 30 70 60 40
NAPLES 72 83 72 88 / 40 80 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
638 PM EDT WED MAY 30 2012
.AVIATION...AS REMNANTS OF BERYL MOV NE ALG THE SE U.S. COAST...A
RDG OF SFC HI PRES...XTNDG W FM THE SW N ATLC OVR THE LWR FLA
STRAITS AND N CUBA INTO THE SE GULF OF MEX...SLOLY MOVS N AND OVR S
FLA AFT 31/12Z. AS THE RDG MOVS N...DEEP TROPICAL MOISTURE OVR THE
SW CARIB IS PULLED NORTHWARD. BUT...VFR XPCTD ALL TERMINALS THRU
31/18Z THOUGH SOME SHRA/PSBL ISOLD TSRA PSBL W COAST AND PSBLY
AFFECTING KAPF OVRNITE. XPCT INCRSD SHRA/TSRA ACTIVITY E COAST AFT
31/18Z AS WNDS ALOFT SW-W AND ACTIVITY WL MOV FM THE INTERIOR AND
THE E COAST DURG THE AFTN HRS. ATTM HAV ONLY VCTS IN E COAST TAFS
SEEING PSBLTY 18 HRS OUT. SFC WNDS BCMG SW AND LESS THAN 10 KTS ALL
TERMINALS THRU 18Z BUT E COAST SEA BRZE SE-SSE ARND 10 KTS TO DVLP.
&&
.PREV DISCUSSION... /ISSUED 229 PM EDT WED MAY 30 2012/
SHORT TERM (TONIGHT-FRIDAY NIGHT)...
THE LATEST NUMERICAL GUIDANCE HAS INITIALIZED WELL WITH THE
CURRENT SYNOPTIC PATTERN AND GENERALLY REMAINS IN GOOD AGREEMENT
THROUGH THE SHORT-TERM PERIOD. DESPITE THE DRIER AIR IN PLACE ACROSS
MUCH OF THE LOCAL AREA...SCATTERED AFTERNOON SHOWERS AND STORMS ARE
EXPECTED TO DEVELOP ACROSS THE EASTERN HALF OF THE LOCAL AREA
THROUGH THE EARLY EVENING PERIOD TODAY...MAINLY ACROSS THE LAKE AND
EAST COAST AREAS. THE LATEST HRRR MODEL REFLECTIVITIES LINE UP WELL
WITH THIS PATTERN CONTINUING THROUGH THE MID-EVENING HOURS BEFORE
TRENDING DOWN THROUGH THE OVERNIGHT PERIOD TONIGHT AND INDICATES THE
BEST COVERAGE REMAINING OVER THE EASTERN AREAS NORTH OF FORT
LAUDERDALE TO THE LAKE ACROSS PALM BEACH COUNTY.
THURSDAY THROUGH FRIDAY...THE MODELS CONTINUE TO INDICATE PLENTY OF
DEEP LAYER MOISTURE SPREADING NORTH ACROSS THE KEYS INTO SOUTH
FLORIDA...WHICH HAS BEEN A PERSISTENT FEATURE OVER THE PAST COUPLE
OF DAYS FROM EACH RUN. THIS INCREASE IN DEEP LAYER MOISTURE COMBINED
WITH SOUTHWEST FLOW ALOFT AHEAD OF AN UPPER TROUGH WILL KEEP THE
RAINFALL CHANCES ELEVATED. MODEL PWAT VALUES REFLECT THIS PATTERN
AND INDICATE VALUES AROUND AND EVEN ABOVE THE TWO INCH MARK. AT THIS
TIME...TOTAL RAINFALL ACCUMULATIONS THROUGH THIS PERIOD ARE FORECAST
TO RANGE FROM 1 TO 3 INCHES NORTH OF ALLIGATOR ALLEY TO 2 TO 4
INCHES SOUTH OF ALLIGATOR ALLEY. AS TYPICALLY OBSERVED DURING THESE
EVENTS...LOCALLY HIGHER AMOUNTS WILL CERTAINLY BECOME A POSSIBILITY
WHERE THE HEAVIER ACTIVITY BECOMES CONCENTRATED. INTERESTS ARE
ENCOURAGED TO MONITOR LATER FORECASTS FOR UPDATES THROUGH THIS TIME.
AS CONFIDENCE CONTINUES TO INCREASE...A FLOOD WATCH MAY BECOME
NECESSARY.
LONG TERM (SATURDAY-TUESDAY)...
THE UPPER TROUGH IS PROGGED TO LIFT NORTHEAST ALLOWING UPPER HEIGHTS
ACROSS THE REGION TO GRADUALLY RISE. THIS COMBINED WITH MUCH DRIER
MID/UPPER LEVEL AIR SPREADING INTO THE AREA WILL LIKELY LIMIT THE
DAILY RAINFALL COVERAGE TO A MORE TYPICAL PATTERN EACH DAY.
MARINE...
LIGHT TO MODERATE SOUTH AND SOUTHWEST WINDS WILL BE EXPECTED
THROUGH THE MID-WEEK PERIOD WITH ISOLATED SHOWERS AND STORMS
REMAINING POSSIBLE EACH DAY. LATE MORNING AND AFTERNOON SEA
BREEZES WILL TRANSLATE TO CHOPPIER CONDITIONS EACH DAY...MAINLY
NEAR THE COAST.
AVIATION...
DRIER AIR HAS WORKED INTO SOUTH FLORIDA FROM THE GULF OF MEXICO
THIS MORNING...AND SHOULD REMAIN OVER SOUTH FLORIDA THROUGH REST
OF TODAY INTO TONIGHT. AT THE SAME TIME...THE EAST COAST SEA
BREEZE WILL DEVELOP AND PUSH SLOWLY INLAND THROUGH THE AFTERNOON
HOURS AND SHOULD STALL BETWEEN KMIA...KFLL...AND KTMB TAF SITES.
THIS MEANS THAT THE MOST OF THE EAST COAST TAF SITES SHOULD BECOME
SOUTHEAST BETWEEN 20Z AND 21Z TODAY...EXCEPT FOR KFXE AND KTMB
WHERE THEY WILL REMAIN SOUTHWEST. THE SPEEDS WILL ALSO BE AT 5 TO
10 KNOTS FOR REST OF THIS AFTERNOON.
THE WINDS WILL THEN SWING BACK TO A SOUTHWEST DIRECTION AFTER 00Z
TONIGHT INTO THURSDAY MORNING WITH SPEEDS AT 5 KNOTS OR LESS ALONG
THE EAST COAST TAF SITES. AT KAPF TAF SITE...THE WINDS WILL REMAIN
SOUTHWEST DIRECTION AT 5 T0 10 KNOTS EXCEPT LESS THAN 5 KNOTS TONIGHT.
THERE COULD BE SOME ISOLATED SHOWERS THIS AFTERNOON OVER MOST OF
THE TAF SITES BEFORE GOING DRY TONIGHT. THE ONLY EXCEPTION IS FOR
KPBI WHERE THERE COULD BE SOME THUNDERSTORMS THIS AFTERNOON. SO
WILL SHOW VCSH FOR ALL TAF SITES UNTIL 00Z TONIGHT...EXCEPT VCTS
FOR KPBI.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 87 73 83 / 20 30 30 60
FORT LAUDERDALE 74 88 74 84 / 20 40 30 60
MIAMI 74 89 74 85 / 20 50 30 60
NAPLES 74 89 74 83 / 10 40 30 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...15/JR
AREA FORECAST DISCUSSION
NWS MIAMI FL
229 PM EDT WED MAY 30 2012
.SHORT TERM (TONIGHT-FRIDAY NIGHT)...
THE LATEST NUMERICAL GUIDANCE HAS INITIALIZED WELL WITH THE
CURRENT SYNOPTIC PATTERN AND GENERALLY REMAINS IN GOOD AGREEMENT
THROUGH THE SHORT-TERM PERIOD. DESPITE THE DRIER AIR IN PLACE ACROSS
MUCH OF THE LOCAL AREA...SCATTERED AFTERNOON SHOWERS AND STORMS ARE
EXPECTED TO DEVELOP ACROSS THE EASTERN HALF OF THE LOCAL AREA
THROUGH THE EARLY EVENING PERIOD TODAY...MAINLY ACROSS THE LAKE AND
EAST COAST AREAS. THE LATEST HRRR MODEL REFLECTIVITIES LINE UP WELL
WITH THIS PATTERN CONTINUING THROUGH THE MID-EVENING HOURS BEFORE
TRENDING DOWN THROUGH THE OVERNIGHT PERIOD TONIGHT AND INDICATES THE
BEST COVERAGE REMAINING OVER THE EASTERN AREAS NORTH OF FORT
LAUDERDALE TO THE LAKE ACROSS PALM BEACH COUNTY.
THURSDAY THROUGH FRIDAY...THE MODELS CONTINUE TO INDICATE PLENTY OF
DEEP LAYER MOISTURE SPREADING NORTH ACROSS THE KEYS INTO SOUTH
FLORIDA...WHICH HAS BEEN A PERSISTENT FEATURE OVER THE PAST COUPLE
OF DAYS FROM EACH RUN. THIS INCREASE IN DEEP LAYER MOISTURE COMBINED
WITH SOUTHWEST FLOW ALOFT AHEAD OF AN UPPER TROUGH WILL KEEP THE
RAINFALL CHANCES ELEVATED. MODEL PWAT VALUES REFLECT THIS PATTERN
AND INDICATE VALUES AROUND AND EVEN ABOVE THE TWO INCH MARK. AT THIS
TIME...TOTAL RAINFALL ACCUMULATIONS THROUGH THIS PERIOD ARE FORECAST
TO RANGE FROM 1 TO 3 INCHES NORTH OF ALLIGATOR ALLEY TO 2 TO 4
INCHES SOUTH OF ALLIGATOR ALLEY. AS TYPICALLY OBSERVED DURING THESE
EVENTS...LOCALLY HIGHER AMOUNTS WILL CERTAINLY BECOME A POSSIBILITY
WHERE THE HEAVIER ACTIVITY BECOMES CONCENTRATED. INTERESTS ARE
ENCOURAGED TO MONITOR LATER FORECASTS FOR UPDATES THROUGH THIS TIME.
AS CONFIDENCE CONTINUES TO INCREASE...A FLOOD WATCH MAY BECOME
NECESSARY.
LONG TERM (SATURDAY-TUESDAY)...
THE UPPER TROUGH IS PROGGED TO LIFT NORTHEAST ALLOWING UPPER HEIGHTS
ACROSS THE REGION TO GRADUALLY RISE. THIS COMBINED WITH MUCH DRIER
MID/UPPER LEVEL AIR SPREADING INTO THE AREA WILL LIKELY LIMIT THE
DAILY RAINFALL COVERAGE TO A MORE TYPICAL PATTERN EACH DAY.
&&
.MARINE...
LIGHT TO MODERATE SOUTH AND SOUTHWEST WINDS WILL BE EXPECTED
THROUGH THE MID-WEEK PERIOD WITH ISOLATED SHOWERS AND STORMS
REMAINING POSSIBLE EACH DAY. LATE MORNING AND AFTERNOON SEA
BREEZES WILL TRANSLATE TO CHOPPIER CONDITIONS EACH DAY...MAINLY
NEAR THE COAST.
&&
.AVIATION...
DRIER AIR HAS WORKED INTO SOUTH FLORIDA FROM THE GULF OF MEXICO
THIS MORNING...AND SHOULD REMAIN OVER SOUTH FLORIDA THROUGH REST
OF TODAY INTO TONIGHT. AT THE SAME TIME...THE EAST COAST SEA
BREEZE WILL DEVELOP AND PUSH SLOWLY INLAND THROUGH THE AFTERNOON
HOURS AND SHOULD STALL BETWEEN KMIA...KFLL...AND KTMB TAF SITES.
THIS MEANS THAT THE MOST OF THE EAST COAST TAF SITES SHOULD BECOME
SOUTHEAST BETWEEN 20Z AND 21Z TODAY...EXCEPT FOR KFXE AND KTMB
WHERE THEY WILL REMAIN SOUTHWEST. THE SPEEDS WILL ALSO BE AT 5 TO
10 KNOTS FOR REST OF THIS AFTERNOON.
THE WINDS WILL THEN SWING BACK TO A SOUTHWEST DIRECTION AFTER 00Z
TONIGHT INTO THURSDAY MORNING WITH SPEEDS AT 5 KNOTS OR LESS ALONG
THE EAST COAST TAF SITES. AT KAPF TAF SITE...THE WINDS WILL REMAIN
SOUTHWEST DIRECTION AT 5 T0 10 KNOTS EXCEPT LESS THAN 5 KNOTS TONIGHT.
THERE COULD BE SOME ISOLATED SHOWERS THIS AFTERNOON OVER MOST OF
THE TAF SITES BEFORE GOING DRY TONIGHT. THE ONLY EXCEPTION IS FOR
KPBI WHERE THERE COULD BE SOME THUNDERSTORMS THIS AFTERNOON. SO
WILL SHOW VCSH FOR ALL TAF SITES UNTIL 00Z TONIGHT...EXCEPT VCTS
FOR KPBI.
&&
.FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 87 73 83 / 20 30 30 60
FORT LAUDERDALE 74 88 74 84 / 20 40 30 60
MIAMI 74 89 74 85 / 20 50 30 60
NAPLES 74 89 74 83 / 10 40 30 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION
NWS MIAMI FL
155 AM EDT WED MAY 30 2012
.AVIATION...
A LIGHT SOUTHWESTERLY FLOW WILL PREVAIL ACROSS THE TERMINALS EARLY
THIS MORNING...WITH A CHANCE OF THE EAST COAST TERMINALS HAVING
LIGHT AND VARIABLE WINDS AT TIMES. MAINLY VFR CONDITIONS EXPECTED
TO PREVAIL THROUGH THE EARLY MORNING HOURS WITH SHOWER ACTIVITY
MAINLY EXPECTED ACROSS THE ATLANTIC WATERS. A SOUTHWESTERLY FLOW
MID MORNING WILL TRANSITION AN EAST COAST SEA BREEZE AROUND
18Z...WITH THE SEA BREEZE SSE AROUND 10 KNOTS EXCEPT FOR TERMINAL
KOPF WHICH COULD REMAIN SSW. SCATTERED SHOWERS AND THUNDERSTORMS
EXPECTED IN VICINITY OF ALL THE EAST COAST TERMINALS WITH VCTS
ASSIGNED AT 18Z.
60
&&
.PREV DISCUSSION... /ISSUED 745 PM EDT TUE MAY 29 2012/
AVIATION...
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DIMINISH OVER THE NEXT
COUPLE OF HOURS. A LIGHT WEST TO SOUTHWEST WIND IS EXPECTED
OVERNIGHT. SHOWERS ARE POSSIBLE NEAR THE EAST COAST TAF SITES
AFTER 15Z...WITH THUNDERSTORMS POSSIBLE BY EARLY TO MID AFTERNOON.
HIGH RES MODELS SHOW AN EAST COAST SEA BREEZE DEVELOPING AROUND
18Z...SO HAVE S TO SE WINDS AT THE EAST COAST TERMINALS AFTER 18Z.
PREV DISCUSSION... /ISSUED 231 PM EDT TUE MAY 29 2012/
SHORT TERM (TONIGHT-THURSDAY NIGHT)...
THE LATEST NUMERICAL GUIDANCE HAS INITIALIZED WELL WITH THE
CURRENT SYNOPTIC PATTERN AND GENERALLY REMAINS IN GOOD AGREEMENT
THROUGH THE SHORT-TERM PERIOD. SIMILAR TO THE PAST COUPLE OF
EVENINGS...MOST OF THE MID TO LATE AFTERNOON HEAVY SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO SETUP OVER THE EASTERN HALF OF THE
SOUTH FLORIDA PENINSULA AND BEGIN TO IMPACT THE EAST COAST AND METRO
LOCATIONS THROUGH THE EARLY EVENING HOURS. THE MAIN IMPACTS FROM THE
STRONGER STORMS THAT DEVELOP THROUGH THIS TIME WILL BE FREQUENT
LIGHTNING...LOCALIZED FLOODING...GUSTY WINDS FROM 40-55 MPH AND
SMALL HAIL. THE LATEST HRRR AND WRF MODEL REFLECTIVITIES LINE UP
WELL WITH THIS PATTERN CONTINUING THROUGH THE MID-EVENING HOURS
BEFORE TRENDING DOWN THROUGH THE OVERNIGHT PERIOD TONIGHT.
WEDNESDAY AND WEDNESDAY NIGHT...AS BERYL CONTINUES TO LIFT NORTHEAST
TO THE CAROLINA COAST OVER THE NEXT COUPLE OF DAYS...THE MODELS
CONTINUE TO INDICATE A SHORTWAVE TROUGH DIGGING SOUTHEAST OVER THE
REGION MAINTAINING A BROAD CYCLONIC UPPER FLOW ACROSS THE AREA. AT
THE SURFACE...THE SUBTROPICAL RIDGE AXIS WILL REMAIN JUST SOUTH OF
THE LOCAL AREA WITH SOUTHWEST FLOW CONTINUING THROUGH THE
LOWER-LEVELS. THE COMBINATION OF THE UPPER TROUGH...DAYTIME HEATING
AND SUFFICIENT SURFACED BASED INSTABILITY WILL BE ENOUGH TO TRIGGER
SCATTERED SHOWERS AND STORMS EACH DAY. WITH THE PRIMARY FLOW THROUGH
THE DEEP LAYER REMAINING OUT OF THE SW...EXPECT THE BULK OF THE
AFTERNOON CONVECTION TO BECOME CONCENTRATED OVER THE EASTERN HALF OF
THE LOCAL AREA EACH DAY.
THURSDAY AND THURSDAY NIGHT...ONE DIFFERENCE TO NOTE FOR THIS PERIOD
IS THE DEEP LAYER MOISTURE THE MODELS CONTINUE TO INDICATE SPREADING
NORTH ACROSS THE KEYS AND THE SOUTH FLORIDA PENINSULA. THIS INCREASE
IN DEEP LAYER MOISTURE COMBINED WITH THE UPPER TROUGH WILL ONLY
ENHANCE THE RAINFALL COVERAGE ACROSS THE LOCAL AREA...ESPECIALLY
THROUGH THE AFTERNOON AND EVENING PERIOD THURSDAY. MODEL PWAT VALUES
REFLECT THIS PATTERN AND GENERALLY INDICATE A NORTH TO SOUTH
GRADIENT ACROSS THE AREA OR FROM THE LAKE TO THE KEYS WITH THE
HIGHER PWAT VALUES REMAINING OVER THE SOUTHERN HALF OF THIS AREA (UP
TO 2.2 INCHES). AS A RESULT...WILL GRADUALLY BEGIN TO INCREASE THE
RAINFALL CHANCES THROUGH THIS PERIOD...ESPECIALLY OVER THESE
SOUTHERN AREAS WHERE THE BEST SOURCE OF DEEP LAYER MOISTURE WILL BE.
LONG TERM (FRIDAY-WEEKEND)...
MODELS REMAIN PERSISTENT INTO THE WEEKEND AND CONTINUE INDICATE THE
PREVIOUSLY DISCUSSED DEEP LAYER MOISTURE SPREADING FARTHER NORTH
ACROSS THE AREA. THIS INCREASING DEEP LAYER MOISTURE SPREADING NORTH
INTO THE LOCAL AREA WILL TRANSLATE TO INCREASING RAINFALL CHANCES
INTO THE WEEKEND. THE LATEST HPC 5 DAY PRECIP FORECAST INDICATES
TOTALS REACHING THE 2-3 INCH RANGE ACROSS THE SOUTHERN END OF THE
PENINSULA. AS TYPICALLY OBSERVED...LOCALLY HIGHER AMOUNTS WILL BE
POSSIBLE WHERE THE BULK OF THE ACTIVITY BECOMES CONCENTRATED.
MARINE...
LIGHT TO MODERATE SOUTH AND SOUTHWEST WINDS WILL BE EXPECTED
THROUGH THE MID-WEEK PERIOD WITH ISOLATED SHOWERS AND STORMS
REMAINING POSSIBLE EACH DAY. LATE MORNING AND AFTERNOON SEA
BREEZES WILL TRANSLATE TO CHOPPIER CONDITIONS EACH DAY...MAINLY
NEAR THE COAST.
FIRE WEATHER...
PLENTY OF MOISTURE SPREADING NORTH OVER THE LOCAL AREA WILL KEEP
RELATIVE HUMIDITY VALUES ABOVE CRITICAL RED FLAG LEVELS THROUGH
THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 74 88 74 / 40 20 40 30
FORT LAUDERDALE 90 76 88 74 / 40 20 50 30
MIAMI 90 75 89 74 / 40 20 50 30
NAPLES 89 74 89 72 / 20 20 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...47/RGH
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NWS PEACHTREE CITY GA
153 AM EDT WED MAY 30 2012
.UPDATE...
/ISSUED AT 950 PM EDT TUE MAY 29 2012/
I HAVE ISSUED A QUICK UPDATE TO RAISE POPS OVER NORTHWEST COUNTIES
AS LINE OF STORMS MOVE OUT OF TENNESSEE...AND LOWERED POPS
SOUTHEAST AS BERYL CONTINUES TO PULL TO THE NORTHEAST. NO OTHER
MAJOR CHANGES MADE AT THIS TIME.
49
&&
.PREV DISCUSSION... /ISSUED 807 PM EDT TUE MAY 29 2012/
PREV DISCUSSION... /ISSUED 340 PM EDT TUE MAY 29 2012/
.CONTINUED LOCALLY HEAVY RAINFALL IN BANDS FROM REMNANTS OF BERYL...
SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
CENTER OF THE REMNANTS OF BERYL HAS NOW ENTERED THE FORECAST AREA
MOVING FROM TELFAIR COUNTY INTO WHEELER. EASTERN SIDE OF THE STORM
HAS DEFINITELY BEEN THE WETTEST IN THE THIS STORMS HISTORY AND
TODAY IS NO DIFFERENT WITH FEEDER BANDS OFF THE ATLANTIC COAST
PROVIDING THE MOST CONSISTENT HEAVY RAINFALL. SHOULD SEE ACTIVITY
LOCALLY ENHANCE THROUGH THE AFTERNOON BUT INSTABILITY WILL REMAIN
MARGINAL DUE TO ENHANCED CLOUD COVER. STILL THINKING THE EASTERN
TIER OF THE FORECAST AREA COULD SEE 1 TO 2 INCHES WITH LOCALLY
HIGHER AMOUNTS WHERE CONVECTIVE BANDS SET UP THROUGH THIS EVENING.
SHEAR IS IMPRESSIVE IN THE LOW LEVELS WITH 30 TO 40 KNOTS AT
925MB...AGAIN OVER THE EASTERN SECTIONS. HAVE JUST NOT HAD THE
INSTABILITY TO TAKE ADVANTAGE OF SHEAR PROFILE THUS FAR BUT WILL
NEED TO MONITOR CELLS CLOSELY FOR POTENTIAL FOR ROTATION IN CELLS
OR ISOLATED STRONG GUSTS.
SEPARATE ARE OVER MISSISSIPPI THIS MORNING DISSIPATED FOR THE
MOST PART AS IT MOVED INTO PORTIONS OF ALABAMA. HRRR STILL KEYING
IN ON NW GEORGIA FOR POSSIBLE LATE TSRA DEVELOPMENT AND HAVE KEPT
LOW END CHANCE POPS IN THERE THROUGH THIS EVENING.
ON THE BACK SIDE OF BERYL...SIGNIFICANTLY DRIER AIR TO WORK ITS
WAY IN WITH SOUNDINGS SHOWING A PROFILE BARELY SUPPORTIVE OF CU
FORMATION IN THE AFTERNOON FROM ATL NORTHWARD. SLIGHTLY BETTER
MOISTURE OVER THE SOUTHERN TIER AND EMBEDDED SHORTWAVE DURING THE
AFTERNOON SHOULD ALLOW FOR LOW END SCT THUNDERSTORM ACTIVITY.
DEESE
LONG TERM /THURSDAY THROUGH TUESDAY/...
TD BERYL PULLS OUT OF THE AREA WEDNESDAY AS A FRONTAL SYSTEM SWEEPS
THROUGH THE STATE. UPPER LEVEL WESTERLY FLOW KEEPS RESIDUAL MOISTURE
OVER THE AREA THROUGH THURSDAY AHEAD OF ANOTHER FRONTAL SYSTEM
MOVING INTO THE STATE FRIDAY. WILL CONTINUE WITH SLIGHT/CHANCE POPS
THROUGH THE END OF THE WEEK. RAIN CHANCES SIGNIFICANTLY INCREASE FOR
THURSDAY AND FRIDAY AS MODELS SHOWING AN UPPER LOW AND ASSOCIATED
FRONTAL BOUNDARY PUSHING EAST OF THE PLAINS ON THURSDAY AND DRAGGING
A COLD FRONT ACROSS THE FORECAST AREA FRIDAY/FRIDAY NIGHT. EXPECT
THE GREATEST THUNDERSTORM THREAT TO BE DURING THE DAY FRIDAY...WITH
2000-2500 CAPE...40KT LOW LEVEL JET AND MODERATE DIFFLUENT FLOW
ALOFT. TOTAL RAINFALL AMOUNTS FOR THURSDAY AND FRIDAY WILL LIKELY BE
AND INCH OR LESS. ONCE THIS FRONT MOVES THROUGH...HIGH PRESSURE
BUILDS IN AND CLEAR TO PARTLY CLOUDY SKIES PREVAIL FOR THE WEEKEND
AND INTO EARLY NEXT WEEK.
01
&&
.AVIATION...
06Z UPDATE...
AN AREA OF -RA WITH CIGS IN THE BKN035-BKN060 RANGE HAS SETTLED IN
OVER THE ATLANTA TAF SITES...BEHIND A LINE OF SHOWERS/TSTMS THAT
MOVED ACROSS AROUND 05Z THIS MORNING. EXPECT THE -RA AND BKN CIGS TO
GRADUALLY DISSIPATE/CLEAR THROUGH 08Z THIS MORNING. OTHERWISE... VFR
CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH SOME PATCHY FOG
IN THE 3SM-6SM BR RANGE POSSIBLY DEVELOPING AROUND 09-11Z THIS
MORNING. THIS SHOULD BURN OFF BY 13-14Z. NW WINDS AROUND 6-8KTS WILL
PREVAIL TODAY...THEN SWING BACK NNE AROUND 06Z TONIGHT. MODELS
SHOW DRIER CONDITIONS OVER THE AREA TODAY...BUT FEW CU AROUND 5 THSD
FT POSSIBLE.
39
//ATL
CONFIDENCE...06Z UPDATE...
MEDIUM ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 91 61 93 / 40 20 10 30
ATLANTA 68 90 66 90 / 20 20 10 30
BLAIRSVILLE 60 85 57 84 / 60 10 5 40
CARTERSVILLE 63 92 58 91 / 50 10 5 50
COLUMBUS 69 93 68 92 / 20 30 20 30
GAINESVILLE 65 91 64 90 / 30 20 5 40
MACON 67 92 62 94 / 40 30 20 30
ROME 66 93 58 91 / 60 10 5 50
PEACHTREE CITY 64 90 60 90 / 20 20 10 30
VIDALIA 70 90 69 94 / 60 30 30 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 AM CDT WED MAY 30 2012
.DISCUSSION...
900 PM CDT
GOING FORECAST LOOKS ON TRACK WITH MINIMAL CHANGES. THE 00Z
REGIONAL ROABS...PARTICULARLY AT DVN...INDICATED THE ATMOSPHERE
MIXED TO AROUND 750 MB TUESDAY UNDER A NOTABLE DRY INTRUSION ON
WATER VAPOR. THE MIXING OF THE SURFACE DEW POINTS HAS NOT STARTED
TO RECOVER THIS EVENING...IN FACT SEVERAL PLACES HAVE DROPPED A
FEW DEGREES IN THE DRY WESTERLY FLOW. THE HEART OF THE CLOSED CELL
CU ON THE LAST VISIBLE SATELLITE IMAGES WAS WELL NORTHWEST OF THE
AREA STILL UNDER THE HEART OF THE COLDER AIR AND MID-LEVEL VORT
LOBES. OBSERVATIONAL TRENDS THEN AND INTO THE EARLY IR IMAGERY OF
TONIGHT DID/DO NOT INDICATE THIS READILY MAKING IT TOWARD THE
IL/WI STATE LINE. RAP FORECASTS OF 850-800 MB RH FOLLOW THIS
TREND. SO WHILE SOME CONTINUAL MIXING WILL KEEP TEMPERATURES FROM
FALLING FAST...THE DRY AIR AND CLEAR SKIES SHOULD ALLOW
TEMPERATURES TO AT LEAST KEEP DROPPING AND MINS TO FALL OUT NEAR
THE GOING FORECAST OF AROUND 50 DEGREES IN MANY PLACES WITH MID
50S IN THE HEART OF CHICAGOLAND. THIS WILL BE THE THE COOLEST
NIGHT IN A WEEK.
MTF
//PREV DISCUSSION...
300 PM CDT
VISIBLE IMAGERY IS SHOWING THE BACK END OF THE CIRRUS PUSHING EAST
FROM SOUTHEAST MI STRETCHING SOUTHWEST THROUGH SOUTHEAST IL. TO THE
WEST OF THIS AREA GOOD LLVL MIXING HAS OCCURRED THIS AFTN AND
ALLOWED FOR ADDITIONAL SUBSIDENCE TO FURTHER DRY THE NEAR SFC
ENVIRONMENT OVER NORTHERN IL/NORTHWEST IN. THE COMBINATION OF
PROLONGED DRY WEATHER IN MANY LOCATIONS ACROSS THE CWFA...WITH
SUBSIDENCE AND WINDS AT TIMES GUSTING IN THE 20-25 MPH RANGE...HAS
ALLOWED FOR SEVERAL LOCATIONS TO REACH RED FLAG CONDITIONS THIS
AFTERNOON WITH RH VALUES ARND 20 PERCENT. THIS IS MAINLY FALLING
BETWEEN THE I-88 AND I-80 CORRIDOR ACROSS NORTHERN IL. NORTH OF THIS
AND RH VALUES HOVER ARND 30 PERCENT...TO THE SOUTH WINDS ARE
LIGHTER.
AFTN TEMPS HAVE PUSHED INTO THE LOWER 80S...WITH TEMPS UPSTREAM
ACROSS NORTHERN IA AND SOUTHWEST WISC REMAIN IN THE LOW/MID 70S. IN
ADDITION DIURNAL CU FIELD HAS DEVELOPED JUST NORTH OF THE CWFA.
EXPECT AS WE LOSE THE SUNLIGHT THE CU FIELD WILL QUICKLY
DISSIPATE...AND SHOULD RESULT IN A MOSTLY CLEAR NIGHT ACROSS
NORTHERN IL. THE COMBINATION OF MINIMAL CLOUDS...DEW POINTS IN THE
LOW/MID 40S...AND A 850MB THERMAL TROUGH OF 6 TO 8 DEG C WILL ALLOW
TEMPS TO COOL INTO THE UPR 40S TO LOW 50S. THE WARMEST LOCATIONS
WILL BE IMMEDIATELY ADJACENT TO LAKE MICHIGAN...WHERE TEMPS COULD
REMAIN IN THE MID 50S.
WEDNESDAY...
THE 500MB WAVE QUICKLY PIVOTS EAST FOR WED AS THE MID-LVL FLOW
BEGINS TO FLATTEN. GENERALLY THIS WOULD AID IN AN EFFICIENT
WEST-EAST FLOW...HOWEVER IT APPEARS THE ANTI-CYCLONIC FLOW OVERHEAD
WED WILL SLOW AS DOWNSTREAM HEIGHTS MAY REMAIN SLIGHTLY LONGER. THIS
WILL ALLOW FOR A DRY WED...BEFORE THE NEXT SYSTEM ARRIVES THUR.
MID-LVL THERMAL TROUGH REMAINS OVERHEAD AND SHOULD LIMIT HOW WARM
THE SFC GETS. AT THIS TIME HAVE ONLY MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST OF HIGHS IN THE LOW/MID 60S NORTH OF I-80. SOUTH
OF I-80 TEMPS COULD APPROACH 70...MAINLY FOR THE FAR SOUTHERN
PORTIONS OF THE CWFA.
THE FOCUS FOR WED NGT WILL BE ON THE DRY AIR THAT APPEARS TO REMAIN
OVERHEAD AND THE DEVELOPING EAST/NORTHEAST FLOW. BAROCLINIC ZONE
BEGINS TO SHARPEN ALONG THE OHIO VALLEY STRETCHING NORTHWEST THROUGH
CENTRAL IA. THE MAIN CHALLENGE FOR WED NGT WILL BE ON THE GRADUAL
SATURATION OF MOISTURE ALOFT AND EVENTUALLY INTO THE MID-LVLS. AT
THIS TIME WED NGT SHOULD REMAIN MAINLY DRY...HOWEVER SEVERAL
SREF/GEFS ENSEMBLE MEMBERS ARE BEGINNING TO SUGGEST PRECIP MAY
PENETRATE THE DRY LYR SHORTLY BEFORE DAYBREAK THUR. HAVE OPTED TO
MENTION THE POSSIBILITY OF THIS SCENARIO AND BROUGHT IN LGT RAIN AFT
MIDNIGHT. TEMPS OVERNIGHT WED WILL HINGE UPON THE TIMING OF THE
RETURNING MOISTURE ALOFT AND HOW QUICKLY THE CLOUDS THICKEN. AT THIS
TIME FEEL CONFIDENT TEMPS WILL BE ABLE TO COOL INTO THE MID/UPR 40S.
GIVEN THE SYSTEM HAS BEGUN TO DEMONSTRATE SOME DEGREE OF
STRENGTHENING...THIS MAY RESULT IN A SLIGHTLY SLOWER SOLUTION. IF
THE SYSTEM INCREASES IN FORWARD SPEED THEN TEMPS MAY NOT BE ABLE TO
COOL AS EFFICIENTLY AS CURRENTLY ADVERTISED.
THURSDAY THROUGH MONDAY...
EXTENDED GUIDANCE MEMBERS HAVE COME INTO SLIGHTLY BETTER AGREEMENT
ON A FEW PARAMETERS WITH THE CUTOFF LOW AND TIMING OF
PRECIP...HOWEVER NOISE ALONG THE LEADING EDGE REMAINS GIVEN THE
STEADY NORTHEAST FLOW AND DRY AIR ENTRAINS INTO THE LOW LEVELS.
FEEL MORE CONFIDENT THAT PRECIP WILL OVERSPREAD THE CWFA BY MIDDAY
THUR...AS THE CUTOFF SHORTWAVE ARRIVES FROM THE WEST. ANTI-CYCLONIC
FLOW NOW APPEARS TO BE PUSHED WELL NORTH OF THE AREA BY THUR
AFTN/EVE...AS A STEADY MOIST CONVEYOR ARRIVES OVER NORTHERN
IL/NORTHWEST IN. EXPECT WELCOME RAINFALL TO ENCOMPASS ALL OF THE
REGION THROUGH MOST OF FRI. GIVEN THE SYSTEM IS SLIGHTLY
STRONGER...IT SHOULD LINGER THRU FRI EVE BEFORE SLIDING EAST FOR
SAT.
WITH THE LACK OF A SIGNIFICANT PUSH OR SYSTEM TO EJECT THE CUTOFF
LOW EAST...THE DRY AIR MAY NOT OCCUR UNTIL SAT EVENING OR PERHAPS
SUN. IN ADDITION TO THE WELCOME RAINFALL LATER IN THE WEEK...WILL BE
THE MUCH COOLER AIR THAT WILL ALSO ENCOMPASS THE REGION. MINIMAL
BREAKS IN THE CLOUD COVER...COMBINED WITH A VERY POTENT 850MB
THERMAL TROUGH AS TEMPS COOL TO ARND 0 DEG C. A FEW SOLUTIONS HAVE
EVEN PROGGED 850MB TEMPS TO COOL TO -2 TO -4 DEG ACROSS PORTIONS OF
WISC. EITHER WAY IT APPEARS THUR HIGH TEMPS WILL STRUGGLE TO WARM
ABOVE THE 50S. LOCATIONS TO OUR NORTH AND NORTHWEST IN WISC/IA/MN
MAY SEE TEMPS HOLD IN THE LOW 50S. SO A COOL...RAINY REGIME LOOKS
LIKELY AT THIS TIME FOR THUR/FRI.
THEN AS THE DEEPER MOISTURE BEGINS TO PEEL NORTHEAST FOR SAT AND
EVENTUALLY SUN...TEMPS STEADILY WARM. WEST COAST RIDGING FINALLY
ARRIVES SUN AND WILL PUSH TEMPS BACK INTO THE LOW/MID 80S. IN
ADDITION THE NEXT CHANCE FOR CONVECTION ARRIVES FOR SUN/MON.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* LAKE BREEZE TIMING WEDNESDAY AFTERNOON..
* AREA OF RAIN OVERSPREADING THE TERMINALS THURSDAY.
BMD
//DISCUSSION...UPDATED 06Z...
OVERNIGHT...LIGHT NORTHWEST FLOW AND CLEAR SKIES WILL CONTINUE AS
HIGH PRESSURE BUILDS ACROSS THE NORTHERN PLAINS INTO THE UPPER
MIDWEST. WEDNESDAY MORNING...EXPECT WINDS TO PICK UP SLIGHTLY AS THE
PRESSURE GRADIENT TIGHTENS AND HIGH BASED CU MAY DEVELOP LATE
MORNING INTO THE AFTERNOON. AS THE HIGH CONTINUES TO MOVE EAST OVER
LAKE MICHIGAN...A SYNOPTICALLY ENHANCED LAKE BREEZE WILL PUSH
ACROSS THE CHICAGO AREA WITH WINDS QUICKLY FLOPPING FROM NNW OVER TO
NORTHEASTERLY.
FOCUS WILL SHIFT TO A LOW PRESSURE LIFTING NORTHEAST ACROSS THE MID
MISSISSIPPI VALLEY EARLY THURSDAY. A MID-LEVEL FGEN BAND IS PROGGED
TO MOVE OVER THE AREA EARLY THURSDAY MORNING WITH SOME MODELS
SUGGESTING PRECIPITATION REACHING THE CHICAGO/ROCKFORD TERMINALS
BETWEEN 06 AND 12Z. GIVEN DRY ANTECEDENT CONDITIONS AND BETTER UPPER
LEVEL SUPPORT ARRIVING LATER IN THE DAY...WILL KEEP MENTION OF
PRECIP OUT OF CURRENT TAFS...BUT WILL INCREASE MID LEVEL CLOUDINESS.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN LAKE BREEZE WEDNESDAY AFTERNOON...LOW TO
MEDIUM CONFIDENCE IN TIMING.
* LOW CONFIDENCE IN PRECIPITATION REACHING TERMINALS BEFORE 12Z
THURSDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY...SHRA LIKELY...MVFR POSSIBLE OVERNIGHT.
FRIDAY...CHANCE OF SHRA...MVFR POSSIBLE.
SATURDAY...SLIGHT CHANCE SHRA EARLY...VFR.
SUNDAY AND MONDAY...CHANCE TSRA.
JEE
&&
.MARINE...
300 AM CDT
HIGH PRESSURE LIES OVER THE NORTHERN PLAINS AND CANADIAN PRAIRIES
THIS MORNING WITH LAKE MICHIGAN IN A MODEST NORTHERLY GRADIENT
TODAY. NORTHWEST TO NORTH WINDS WILL BECOME NORTHEASTERLY THIS
EVENING AS THE RIDGE AXIS SHIFTS EAST. LOW PRESSURE OVER THE
TEXAS PANHANDLE WILL BEGIN TO LIFT NORTHEAST...REACHING THE GREAT
LAKES REGION FRIDAY. MODERATELY STRONG NORTHEAST TO NORTH WINDS
ARE EXPECTED ON THE NORTH SIDE OF THE LOW. WINDS ARE EXPECTED TO
TOP OUT AROUND 30 KT...BUT CANNOT RULE OUT A FEW GUSTS TO GALE
FORCE. HEADLINES FOR SMALL CRAFT ADVISORY MAY BE NEEDED AS EARLY
AS THURSDAY AFTERNOON...BUT THE STRONGEST WIND ARE EXPECTED
THURSDAY NIGHT THROUGH MIDDAY FRIDAY. THIS WEEKEND...WINDS SHOULD
BECOME WESTERLY AND GRADUALLY TAPER AS THE LOW DEPARTS. BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1224 AM CDT WED MAY 30 2012
.DISCUSSION...
900 PM CDT
GOING FORECAST LOOKS ON TRACK WITH MINIMAL CHANGES. THE 00Z
REGIONAL ROABS...PARTICULARLY AT DVN...INDICATED THE ATMOSPHERE
MIXED TO AROUND 750 MB TUESDAY UNDER A NOTABLE DRY INTRUSION ON
WATER VAPOR. THE MIXING OF THE SURFACE DEW POINTS HAS NOT STARTED
TO RECOVER THIS EVENING...IN FACT SEVERAL PLACES HAVE DROPPED A
FEW DEGREES IN THE DRY WESTERLY FLOW. THE HEART OF THE CLOSED CELL
CU ON THE LAST VISIBLE SATELLITE IMAGES WAS WELL NORTHWEST OF THE
AREA STILL UNDER THE HEART OF THE COLDER AIR AND MID-LEVEL VORT
LOBES. OBSERVATIONAL TRENDS THEN AND INTO THE EARLY IR IMAGERY OF
TONIGHT DID/DO NOT INDICATE THIS READILY MAKING IT TOWARD THE
IL/WI STATE LINE. RAP FORECASTS OF 850-800 MB RH FOLLOW THIS
TREND. SO WHILE SOME CONTINUAL MIXING WILL KEEP TEMPERATURES FROM
FALLING FAST...THE DRY AIR AND CLEAR SKIES SHOULD ALLOW
TEMPERATURES TO AT LEAST KEEP DROPPING AND MINS TO FALL OUT NEAR
THE GOING FORECAST OF AROUND 50 DEGREES IN MANY PLACES WITH MID
50S IN THE HEART OF CHICAGOLAND. THIS WILL BE THE THE COOLEST
NIGHT IN A WEEK.
MTF
//PREV DISCUSSION...
300 PM CDT
VISIBLE IMAGERY IS SHOWING THE BACK END OF THE CIRRUS PUSHING EAST
FROM SOUTHEAST MI STRETCHING SOUTHWEST THROUGH SOUTHEAST IL. TO THE
WEST OF THIS AREA GOOD LLVL MIXING HAS OCCURRED THIS AFTN AND
ALLOWED FOR ADDITIONAL SUBSIDENCE TO FURTHER DRY THE NEAR SFC
ENVIRONMENT OVER NORTHERN IL/NORTHWEST IN. THE COMBINATION OF
PROLONGED DRY WEATHER IN MANY LOCATIONS ACROSS THE CWFA...WITH
SUBSIDENCE AND WINDS AT TIMES GUSTING IN THE 20-25 MPH RANGE...HAS
ALLOWED FOR SEVERAL LOCATIONS TO REACH RED FLAG CONDITIONS THIS
AFTERNOON WITH RH VALUES ARND 20 PERCENT. THIS IS MAINLY FALLING
BETWEEN THE I-88 AND I-80 CORRIDOR ACROSS NORTHERN IL. NORTH OF THIS
AND RH VALUES HOVER ARND 30 PERCENT...TO THE SOUTH WINDS ARE
LIGHTER.
AFTN TEMPS HAVE PUSHED INTO THE LOWER 80S...WITH TEMPS UPSTREAM
ACROSS NORTHERN IA AND SOUTHWEST WISC REMAIN IN THE LOW/MID 70S. IN
ADDITION DIURNAL CU FIELD HAS DEVELOPED JUST NORTH OF THE CWFA.
EXPECT AS WE LOSE THE SUNLIGHT THE CU FIELD WILL QUICKLY
DISSIPATE...AND SHOULD RESULT IN A MOSTLY CLEAR NIGHT ACROSS
NORTHERN IL. THE COMBINATION OF MINIMAL CLOUDS...DEW POINTS IN THE
LOW/MID 40S...AND A 850MB THERMAL TROUGH OF 6 TO 8 DEG C WILL ALLOW
TEMPS TO COOL INTO THE UPR 40S TO LOW 50S. THE WARMEST LOCATIONS
WILL BE IMMEDIATELY ADJACENT TO LAKE MICHIGAN...WHERE TEMPS COULD
REMAIN IN THE MID 50S.
WEDNESDAY...
THE 500MB WAVE QUICKLY PIVOTS EAST FOR WED AS THE MID-LVL FLOW
BEGINS TO FLATTEN. GENERALLY THIS WOULD AID IN AN EFFICIENT
WEST-EAST FLOW...HOWEVER IT APPEARS THE ANTI-CYCLONIC FLOW OVERHEAD
WED WILL SLOW AS DOWNSTREAM HEIGHTS MAY REMAIN SLIGHTLY LONGER. THIS
WILL ALLOW FOR A DRY WED...BEFORE THE NEXT SYSTEM ARRIVES THUR.
MID-LVL THERMAL TROUGH REMAINS OVERHEAD AND SHOULD LIMIT HOW WARM
THE SFC GETS. AT THIS TIME HAVE ONLY MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST OF HIGHS IN THE LOW/MID 60S NORTH OF I-80. SOUTH
OF I-80 TEMPS COULD APPROACH 70...MAINLY FOR THE FAR SOUTHERN
PORTIONS OF THE CWFA.
THE FOCUS FOR WED NGT WILL BE ON THE DRY AIR THAT APPEARS TO REMAIN
OVERHEAD AND THE DEVELOPING EAST/NORTHEAST FLOW. BAROCLINIC ZONE
BEGINS TO SHARPEN ALONG THE OHIO VALLEY STRETCHING NORTHWEST THROUGH
CENTRAL IA. THE MAIN CHALLENGE FOR WED NGT WILL BE ON THE GRADUAL
SATURATION OF MOISTURE ALOFT AND EVENTUALLY INTO THE MID-LVLS. AT
THIS TIME WED NGT SHOULD REMAIN MAINLY DRY...HOWEVER SEVERAL
SREF/GEFS ENSEMBLE MEMBERS ARE BEGINNING TO SUGGEST PRECIP MAY
PENETRATE THE DRY LYR SHORTLY BEFORE DAYBREAK THUR. HAVE OPTED TO
MENTION THE POSSIBILITY OF THIS SCENARIO AND BROUGHT IN LGT RAIN AFT
MIDNIGHT. TEMPS OVERNIGHT WED WILL HINGE UPON THE TIMING OF THE
RETURNING MOISTURE ALOFT AND HOW QUICKLY THE CLOUDS THICKEN. AT THIS
TIME FEEL CONFIDENT TEMPS WILL BE ABLE TO COOL INTO THE MID/UPR 40S.
GIVEN THE SYSTEM HAS BEGUN TO DEMONSTRATE SOME DEGREE OF
STRENGTHENING...THIS MAY RESULT IN A SLIGHTLY SLOWER SOLUTION. IF
THE SYSTEM INCREASES IN FORWARD SPEED THEN TEMPS MAY NOT BE ABLE TO
COOL AS EFFICIENTLY AS CURRENTLY ADVERTISED.
THURSDAY THROUGH MONDAY...
EXTENDED GUIDANCE MEMBERS HAVE COME INTO SLIGHTLY BETTER AGREEMENT
ON A FEW PARAMETERS WITH THE CUTOFF LOW AND TIMING OF
PRECIP...HOWEVER NOISE ALONG THE LEADING EDGE REMAINS GIVEN THE
STEADY NORTHEAST FLOW AND DRY AIR ENTRAINS INTO THE LOW LEVELS.
FEEL MORE CONFIDENT THAT PRECIP WILL OVERSPREAD THE CWFA BY MIDDAY
THUR...AS THE CUTOFF SHORTWAVE ARRIVES FROM THE WEST. ANTI-CYCLONIC
FLOW NOW APPEARS TO BE PUSHED WELL NORTH OF THE AREA BY THUR
AFTN/EVE...AS A STEADY MOIST CONVEYOR ARRIVES OVER NORTHERN
IL/NORTHWEST IN. EXPECT WELCOME RAINFALL TO ENCOMPASS ALL OF THE
REGION THROUGH MOST OF FRI. GIVEN THE SYSTEM IS SLIGHTLY
STRONGER...IT SHOULD LINGER THRU FRI EVE BEFORE SLIDING EAST FOR
SAT.
WITH THE LACK OF A SIGNIFICANT PUSH OR SYSTEM TO EJECT THE CUTOFF
LOW EAST...THE DRY AIR MAY NOT OCCUR UNTIL SAT EVENING OR PERHAPS
SUN. IN ADDITION TO THE WELCOME RAINFALL LATER IN THE WEEK...WILL BE
THE MUCH COOLER AIR THAT WILL ALSO ENCOMPASS THE REGION. MINIMAL
BREAKS IN THE CLOUD COVER...COMBINED WITH A VERY POTENT 850MB
THERMAL TROUGH AS TEMPS COOL TO ARND 0 DEG C. A FEW SOLUTIONS HAVE
EVEN PROGGED 850MB TEMPS TO COOL TO -2 TO -4 DEG ACROSS PORTIONS OF
WISC. EITHER WAY IT APPEARS THUR HIGH TEMPS WILL STRUGGLE TO WARM
ABOVE THE 50S. LOCATIONS TO OUR NORTH AND NORTHWEST IN WISC/IA/MN
MAY SEE TEMPS HOLD IN THE LOW 50S. SO A COOL...RAINY REGIME LOOKS
LIKELY AT THIS TIME FOR THUR/FRI.
THEN AS THE DEEPER MOISTURE BEGINS TO PEEL NORTHEAST FOR SAT AND
EVENTUALLY SUN...TEMPS STEADILY WARM. WEST COAST RIDGING FINALLY
ARRIVES SUN AND WILL PUSH TEMPS BACK INTO THE LOW/MID 80S. IN
ADDITION THE NEXT CHANCE FOR CONVECTION ARRIVES FOR SUN/MON.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* LAKE BREEZE TIMING WEDNESDAY AFTERNOON..
* AREA OF RAIN OVERSPREADING THE TERMINALS THURSDAY.
BMD
//DISCUSSION...UPDATED 06Z...
OVERNIGHT...LIGHT NORTHWEST FLOW AND CLEAR SKIES WILL CONTINUE AS
HIGH PRESSURE BUILDS ACROSS THE NORTHERN PLAINS INTO THE UPPER
MIDWEST. WEDNESDAY MORNING...EXPECT WINDS TO PICK UP SLIGHTLY AS THE
PRESSURE GRADIENT TIGHTENS AND HIGH BASED CU MAY DEVELOP LATE
MORNING INTO THE AFTERNOON. AS THE HIGH CONTINUES TO MOVE EAST OVER
LAKE MICHIGAN...A SYNOPTICALLY ENHANCED LAKE BREEZE WILL PUSH
ACROSS THE CHICAGO AREA WITH WINDS QUICKLY FLOPPING FROM NNW OVER TO
NORTHEASTERLY.
FOCUS WILL SHIFT TO A LOW PRESSURE LIFTING NORTHEAST ACROSS THE MID
MISSISSIPPI VALLEY EARLY THURSDAY. A MID-LEVEL FGEN BAND IS PROGGED
TO MOVE OVER THE AREA EARLY THURSDAY MORNING WITH SOME MODELS
SUGGESTING PRECIPITATION REACHING THE CHICAGO/ROCKFORD TERMINALS
BETWEEN 06 AND 12Z. GIVEN DRY ANTECEDENT CONDITIONS AND BETTER UPPER
LEVEL SUPPORT ARRIVING LATER IN THE DAY...WILL KEEP MENTION OF
PRECIP OUT OF CURRENT TAFS...BUT WILL INCREASE MID LEVEL CLOUDINESS.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN LAKE BREEZE WEDNESDAY AFTERNOON...LOW TO
MEDIUM CONFIDENCE IN TIMING.
* LOW CONFIDENCE IN PRECIPITATION REACHING TERMINALS BEFORE 12Z
THURSDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY...SHRA LIKELY...MVFR POSSIBLE OVERNIGHT.
FRIDAY...CHANCE OF SHRA...MVFR POSSIBLE.
SATURDAY...SLIGHT CHANCE SHRA EARLY...VFR.
SUNDAY AND MONDAY...CHANCE TSRA.
JEE
&&
.MARINE...
214 PM CDT
HIGH PRESSURE WILL BUILD EASTWARD FROM THE UPPER MISSISSIPPI VALLEY
ACROSS LAKE MICHIGAN ON WEDNESDAY. AS THIS OCCURS...A PRESSURE
GRADIENT WILL REMAIN CONDUCIVE TO NORTHERLY WINDS UP AROUND 20 KT
ACROSS THE EASTERN AND FAR SOUTHERN SECTIONS OF THE LAKE THROUGH THE
DAY ON WEDNESDAY.
THE NEXT SIGNIFICANT CONCERN WILL BE FOR THURSDAY THROUGH FRIDAY AS
A POTENT AREA OF LOW PRESSURE LIFTS NORTHEASTWARD FROM THE SOUTHERN
PLAINS ACROSS THE MID MISSISSIPPI VALLEY AND GREAT LAKES REGION.
THIS SYSTEM LOOKS TO PRODUCE STRONGER NORTHEASTERLY FLOW LATER ON
THURSDAY BEFORE SWITCHING MORE NORTHERLY ON FRIDAY AS THE SURFACE
LOW LIFTS NORTHWARD ACROSS EASTERN MICHIGAN. UNCERTAINTY IS STILL
HIGH WITH REGARDS TO THE EXACT TIMING AND TRACK OF THIS LOW.
HOWEVER...IT DOES APPEAR THAT WINDS WILL INCREASE UP TO 25 TO AROUND
30 KT LATER THURSDAY...ESPECIALLY ACROSS SOUTHERN LAKE MICHIGAN.
THESE STRONGER NORTHERLY WINDS MAY SPREAD NORTHWARD ACROSS THE
WHOLE LAKE LATER THURSDAY NIGHT AND FRIDAY...DEPENDING ON THE
EXACT TRACK OF THE SURFACE LOW ON FRIDAY.
THE WINDS SHOULD BECOME WESTERLY AND ABATE OVER THE WEEKEND AS THE
SURFACE LOW LIFTS NORTHWARD ACROSS EASTERN ONTARIO.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
303 PM CDT WED MAY 30 2012
.DISCUSSION...
SHORT TERM - THROUGH THURSDAY...
19Z WATER VAPOR IMAGERY SHOWS A COMPACT SHORTWAVE DIVING SOUTHEAST
INTO SD. ELEVATED STORMS HAVE PERSISTED ACROSS CENTRAL NEB DUE TO
THIS WAVE. AT THE SFC...A WARM FRONT IS LIFTING NORTH THROUGH THE
FORECAST AREA WITH DEEPER MOISTURE ADVECTING NORTH INTO CENTRAL
AND WESTERN KS. AT 19Z THE WARM FRONT WAS NEAR OR JUST SOUTH OF
THE KS RIVER.
FOR TONIGHT...THUNDERSTORMS ARE EXPECTED TO BECOME WIDESPREAD AND
MOVE SOUTHEAST ACROSS THE AREA. THE PAST SEVERAL RUNS OF THE HIGH
RES HRRR HAVE SUGGESTED THAT AN ISOLATED STORM OR TWO MAY TRY TO
DEVELOP ON THE WARM FRONT AROUND 4 PM...THEN A LINEAR CONVECTIVE
SYSTEM MOVE ACROSS THIS EVENING. WITH THE WARM SECTOR MOVING INTO
THE AREA...INSTABILITY HAS BEEN INCREASING. MID LEVEL LAPSE RATES
ARE NEAR 8 C/KM WITH ML CAPE AS HIGH AS 2000 J/KG. SO THERE WOULD BE
ENOUGH INSTABILITY FOR STORMS TO BECOME SEVERE. IF DISCRETE STORMS
ARE ABLE TO DEVELOP THIS AFTERNOON ALONG THE WARM FRONT...THERE
COULD BE A TORNADO THREAT INITIALLY. HOWEVER LOW LEVEL SHEER IS
RATHER MARGINAL SO THIS WOULD WORK AGAINST TORNADOS. IF THE LINE OF
STORMS IS ABLE TO FORM A STRONG COLD POOL...STRONG STRAIGHT LINE
WINDS MAY BE MORE OF A CONCERN AFTER DARK IN EASTERN KS. SO WITH THE
STRONG DYNAMICS FROM THE UPPER WAVE AND INCREASING MOISTURE FROM THE
SOUTH...WILL INCREASE POPS FOR TONIGHT TO CATEGORICAL. EXPECT LOWS
TO BE FAIRLY SIMILAR TO THE PREV FORECAST WITH AROUND 50 IN THE FAR
NORTHWEST TO NEAR 60 IN THE FAR SOUTHEAST.
BY THURSDAY...THINK THAT THE BULK OF CONVECTION WILL BE MOVING EAST
OF THE AREA AS THE SHORTWAVE BEGINS TO CLOSE OFF OVER THE MID MS
RIVER VALLEY. MODELS INDICATE THERE IS STILL SOME PV ANOMALIES
MOVING AROUND THE BACK SIDE OF THE UPPER WAVE ALONG THE MO RIVER.
ALTHOUGH MUCH IF NOT ALL OF THE INSTABILITY SHOULD BE SHIFTED TO THE
EAST. SO THERE MAY BE SOME PRECIP LINGER ACROSS NORTHEAST KS DURING
THE DAY. BUT WOULD EXPECT THAT TO BE MAINLY SHOWERS. THERE COULD BE
SOME INSOLATION THURSDAY...ESPECIALLY ACROSS NORTH CENTRAL KS AND
WITH THE MODELS TENDED TO BE A LITTLE COOL THE PAST COUPLE
DAYS...HAVE BUMPED UP HIGHS TO THE UPPER 60S AND AROUND 70 IN NORTH
CENTRAL AND EAST CENTRAL KS AND THE MID 60S NORTHEAST WHERE CLOUD
COVER AND PRECIP CHANCES SHOULD BE HIGHER.
WOLTERS
MID TERM - THURSDAY NIGHT THROUGH SATURDAY...
THERE ARE TWO PRIMARY WEATHER STORIES IN THE MID TERM. THE FIRST
SURROUNDS A CHILLY START TO FRIDAY MORNING. A COOL AIRMASS WILL
SETTLE OVERHEAD WHILE SURFACE HIGH PRESSURE DRIFTS ACROSS EASTERN
KANSAS. EXPECT MOST CLOUD COVER TO HOLD OFF UNTIL AFTER SUNRISE SO
THE COMBINATION OF LIGHT WINDS...CLEAR SKIES...AND A COOL AIRMASS
SHOULD LEAD TO MORNING LOWS IN THE MIDDLE 40S. ANY UNCERTAINTY IN
THIS COLD FORECAST WOULD REST WITH CLOUD COVER POTENTIAL AS ANY MID
CLOUDS MOVING IN FROM THE WEST WOULD RESULT IN A SHARP JUMP IN LOW
TEMPS UNDER THE CLOUDS.
THE OTHER FOCUS DURING THE MID TERM IS ON RAIN CHANCES FRIDAY INTO
FRIDAY NIGHT. A CLOSED UPPER TROUGH WILL REMAIN NEARLY STATIONARY
OVER THE GREAT LAKES ON FRIDAY WHILE A SHORT WAVE TROUGH WILL PASS
THROUGH NEBRASKA AND EASTERN KANSAS ON THE BACK SIDE OF THE MAIN
SYSTEM. IT APPEARS THAT THERE WILL BE AN ENHANCED ZONE OF
ISENTROPIC ASCENT ACROSS THE AREA ALONG A MID LEVEL FRONTAL
BOUNDARY LOOSELY ASSOCIATED WITH THIS SHORT WAVE. THE ADDITION OF
WEAK UPPER LEVEL ASCENT ASSOCIATED WITH THE WAVE AND A VERY WEAK
SURFACE COLD FRONT SHOULD LEAD TO ISOLATED TO SCATTERED SHOWERS
WITH A THUNDERSTORM OR TWO POSSIBLE. THE BEST PRECIP CHANCES
APPEAR TO COME LATE FRIDAY AFTERNOON INTO EARLY SATURDAY
MORNING...AND DO NOT EXPECT MUCH MORE THAN SCATTERED LIGHT TO
MODERATE RAIN.
A WARMING TREND WILL BEGIN FOR SATURDAY WITH SOME WARM AIR
ADVECTION ALOFT AND PLENTY OF SUNSHINE BRINGING HIGHS INTO THE
80S.
BARJENBRUCH
LONG TERM - SUNDAY THROUGH WEDNESDAY...
A LONG WAVE TROUGH AXIS WILL SET UP ACROSS THE EASTERN HALF OF THE
CONUS WHILE LONG WAVE RIDGING GRADUALLY INCREASES ACROSS THE
ROCKIES AND HIGH PLAINS. EXPECT THE LOCAL FORECAST AREA TO BE IN A
BIT OF A PINCH POINT BETWEEN THE TROUGH AND RIDGE THROUGH THE
FIRST PART OF THE EXTENDED PERIOD WITH EPISODES OF ENHANCED LIFT
ACROSS THE AREA AS WARM ADVECTION ATTEMPTS TO SURGE NORTH OVER A
WEAK STATIONARY FRONTAL BOUNDARY DRAPED ACROSS KANSAS. THUS...IT
WILL BE A FAIRLY UNSETTLED PERIOD WITH OCCASIONAL CHANCES FOR
THUNDERSTORMS BOTH DURING THE PEAK HEATING HOURS AS WELL AS SOME
POTENTIAL FOR OVERNIGHT MCS ACTIVITY. THE BEST CHANCE FOR
WIDESPREAD PRECIP APPEARS TO COME SUNDAY NIGHT AS A SHORT WAVE
TROUGH MOVES OVER THE RIDGE AND ACROSS THE REGION. THE BEST CHANCE
FOR DRY WEATHER APPEARS TO COME MONDAY THROUGH TUESDAY AS SLIGHTLY
DRIER AIR MOVES IN...BUT THUNDERSTORM CHANCES COME BACK INTO THE
FORECAST BY THE MIDDLE OF NEXT WEEK AS A TROUGH DEEPENS OVER THE
ROCKIES AND MOISTURE PUSHES BACK NORTH INTO THE AREA.
TEMPERATURES WILL BE WARM...LIKELY IN THE 90S AT TIMES...BUT WILL
ALSO BE HIGHLY DEPENDENT UPON CLOUD COVER. ANY SUNNY DAYS IN THE
LONG TERM WILL LIKELY RESULT IN HIGHS AT LEAST IN THE LOWER 90S
WHILE LOW TEMPS MOST NIGHTS SHOULD BE IN THE UPPER 60S TO AROUND
70.
BARJENBRUCH
&&
.AVIATION...
EXPECT VFR CONDITIONS THROUGH 02Z ALL SITES. DO EXPECT -TSRA TO
AFFECT TERMINALS 02Z TO 04Z MHK AND 03Z TO 05Z TOP/FOE AS COLD FRONT
MOVES SOUTHEAST ACROSS KANSAS. EXPECT WIND SHIFT AFT 08Z MHK AND
09Z TOP/FOE. MVFR CIGS POSSIBLE 02Z TO 09Z BECOMING VFR AFT 09Z.
BYRNE
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
258 PM CDT WED MAY 30 2012
...UPDATED FOR LONG TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 120 PM CDT WED MAY 30 2012
AS OF 17Z...AN AXIS OF 62-64F DEWPOINTS WERE OBSERVED ACROSS THE
EASTERN TEXAS PANHANDLE AND ADJACENT EXTREME WESTERN OKLAHOMA ALONG
AND WEST OF THE REMNANT OUTFLOW BOUNDARY FROM LAST NIGHTS OKLAHOMA
THUNDERSTORM COMPLEX. TEMPERATURES WERE WARMING INTO THE LOWER 80S
ACROSS MUCH OF SOUTHWEST KANSAS ON A SOUTHEAST WIND...ALLOWING
SURFACE-BASED CAPE VALUES TO EXCEED 2000 J/KG ALONG THE MOISTURE
AXIS. VISIBLE SATELLITE SHOWED A FAIRLY LARGE AREA OF STRATOCUMULUS
CLOUDS WITHIN THE MOISTURE AXIS ACROSS MUCH OF SOUTHWEST KANSAS. A
LOOK OUT THE WINDOW HERE AT THE WEATHER OFFICE CONFIRMED FAIRLY FLAT
LOOKING CUMULUS AS OF 1755 UTC. A WEAK BUT IMPORTANT SURFACE
BOUNDARY WAS OBSERVED FROM JUST SOUTH OF RUSSELL, KS
WEST-NORTHWESTWARD TO NEAR GOVE, KS. TEMPERATURES NORTH OF THIS
BOUNDARY WERE STILL HANGING IN THE LOWER 70S...WITH TEMPERATURES
RISING INTO THE LOWER 80S SOUTH OF THE BOUNDARY ACROSS MUCH OF
SOUTHWEST KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 120 PM CDT WED MAY 30 2012
THE HRRR AND RAP MODELS HAVE SHOWN A PERSISTENT CONVECTIVE
INITIATION SIGNAL ACROSS WEST CENTRAL OR SOUTHWEST KANSAS...ROUGHLY
IN AN AREA BOUNDED BY KALVESTA-GOVE-NESS CITY-KALVESTA...BY 20 TO
21Z. THIS WOULD SEEM TO MATCH THE LOCATION OF WHERE THE BOUNDARY
IS...ALTHOUGH IS A BIT FARTHER SOUTH. IT WOULD SEEM THE BEST AREA
FOR CONVECTIVE INITIATION WOULD BE JUST NORTH OF WHERE THE LATEST
HRRR RUNS HAVE IT...BUT EITHER WAY CONVECTIVE INITIATION SHOULD
OCCUR BY NO LATER THAN 22Z NORTH OF HIGHWAY 50 AND ALONG/SOUTH OF
INTERSTATE 70 IN SOUTHWEST/WEST-CENTRAL KANSAS. THE EARLY STAGE OF
CONVECTIVE MODE SHOULD BE SUPERCELLULAR WITH SURFACE-BASED CAPE
CONTINUING TO INCREASE ABOVE 3000 J/KG AND A SUBSTANTIAL AMOUNT OF
DEEP LAYER SHEAR TO SUPPORT VIGOROUS SUPERCELL THUNDERSTORMS.
SUPERCELL STORM MOTION WILL BE SOUTHEAST AT AROUND 20 TO 25 KNOTS
(NON SUPERCELL STORM MOTION BEING MORE EASTERLY). THE STORM
PREDICTION CENTER (SPC) PROBABILISTIC HAIL AND WIND ARE VERY HIGH
ACROSS MUCH OF THE DDC FORECAST AREA...INCLUDING ALL POINTS SOUTH OF
HIGHWAY 4 AND EAST OF HIGHWAY 83. THE SPC PROBABILISTIC SEVERE
WEATHER THREATS LOOK PRETTY GOOD AND AGREE ON JUST ABOUT ALL
ACCOUNTS. THE ONLY THING I QUESTION IS THE TORNADO POTENTIAL...AS
CONVECTIVE MODE AFTER A FEW HOURS MAY TRANSITION MORE TO A
QUASI-LINEAR SIGNIFICANT SEVERE EPISODE (DAMAGING TO DESTRUCTIVE
WIND POTENTIAL 80+ MPH). THIS MAY NOT OCCUR UNTIL LATER THIS
EVENING AS THE SEVERE WEATHER EVENT SHIFTS INTO OKLAHOMA. IF THE
SUPERCELL PHASE CAN LAST SEVERAL HOURS THEN THE TORNADO POTENTIAL
WILL DEFINITELY BE ENHANCED...AND FOR THAT REASON THE 10 PERCENT
TORNADO POTENTIAL (PROB OF A TORNADO WITHIN 25 MILES OF A POINT)
DOES LOOK JUSTIFIED FOR AREAS GENERALLY SOUTHEAST OF A LIBERAL TO
JETMORE TO LARNED LINE. DURING THE EVENING HOURS...THE SEVERE
WEATHER THREAT WILL DIMINISH FROM NORTH TO SOUTH AS THE MAIN AREA
SHIFTS INTO NORTHERN OKLAHOMA...HOWEVER WILL MAINTAIN SOME 20-50
POPS IN THE SOUTHEAST HALF OF THE FORECAST AREA THROUGH THE 06-09Z
TIME FRAME AS ADDITIONAL STORMS MAY DEVELOP IN THE WAKE OF THE
PRIMARY ROUND. ANYTHING DEVELOPING AFTER THE PRIMARY ROUND WILL
HAVE MUCH LESS INSTABILITY TO WORK WITH AND THE SEVERE WEATHER
THREAT SHOULD BE RATHER LOW.
THE REST OF THE FORECAST FOR LATE TONIGHT AND TOMORROW WAS
ESSENTIALLY UNCHANGED AS SUBSIDENCE AND DRIER AIR MOVES IN ON
NORTHEAST WINDS. TEMPERATURES WILL STRUGGLE TO ESCAPE THE LOWER 70S
OVER MUCH OF SOUTHWEST KANSAS ON THURSDAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 256 PM CDT WED MAY 30 2012
AFTER THE SHORTWAVE TROUGH MENTIONED IN THE SHORT TERM DISCUSSION
PASSES TO THE EAST, SURFACE HIGH PRESSURE WILL BUILD INTO WESTERN
KANSAS THURSDAY AND THURSDAY NIGHT. THURSDAY WILL BE COOLER BEHIND
THE FRONT WITH HIGHS IN THE 70S. THURSDAY NIGHT`S LOWS WILL BE FAIRLY
CHILLY IN THE 40S AS SKIES REMAIN PARTLY CLOUDY WITH FAIRLY LIGHT
SOUTHERLY WINDS. HOWEVER, IF THERE ARE MORE CLOUDS THAN CLEAR AREAS,
THEN UPPER 40S WOULD BE MORE LIKELY THAN LOWER OR MID 40S. THERE IS
A VERY SLIGHT CHANCE OF ELEVATED SHOWERS DEVELOPING TOWARD THURSDAY
MORNING AS WARM ADVECTION BEGINS IN THE ABSENCE OF SIGNIFICANT
MID-LEVEL CAPPING.
WEAK UPPER-LEVEL RIDGING IS PROGGED BY ALL THE MODELS TO DEVELOP
ACROSS THE ROCKIES BY FRIDAY AND SATURDAY AND PERSIST INTO SUNDAY,
WITH NORTHWEST TO WEST-NORTHWESTERLY MID TO HIGH-LEVEL FLOW ACROSS
THE ROCKIES. THERE WILL BE A SLIGHT MID-LEVEL DOWNSLOPE COMPONENT
ACROSS THE ROCKIES, WHICH WILL TEND TO SUPPORT SOUTHERLY WINDS AND
MOISTURE TRANSPORT INTO KANSAS. GIVEN THAT MID-LEVEL CAPPING TENDS
TO BE WEAK IN THESE REGIMES, NOCTURNAL STORM CLUSTERS COULD DEVELOP
SOMEWHERE ACROSS THE CENTRAL PLAINS IN THE MID-LEVEL BAROCLINIC
ZONE, POSSIBLY AS EARLY AS THURSDAY NIGHT(AS ALREADY MENTIONED), BUT
MORE LIKELY BY FRIDAY NIGHT. THE WARMEST TEMPERATURES FRIDAY AND
SATURDAY WILL BE IN FAR SOUTHWEST KANSAS CLOSER TO THE LEE TROUGH
WHERE HIGHS COULD REACH INTO THE UPPER 80S TO LOWER 90S, WHILE
SLIGHTLY COOLER TEMPERATURES CAN BE EXPECTED FURTHER EAST. THE MID
TO UPPER-LEVEL FLOW WILL BECOME MORE ZONAL BY SUNDAY, ALLOWING FOR
SOME LOWERING OF SURFACE PRESSURES AND WARM ADVECTION IN THE LEE OF
THE ROCKIES ALONG WITH WARMING TEMPERATURES IN THE LOWER TROPOSPHERE
ACROSS THE CENTRAL PLAINS. HIGHS COULD REACH TO BETWEEN 95 AND 100F.
A DEEP UPPER-LEVEL TROUGH WILL AMPLIFY OFF OF THE WEST COAST BY
MONDAY, WITH UPPER-LEVEL RIDGING ACROSS THE PLAINS. MONDAY SHOULD BE
FAIRLY DRY WITH HIGH AFTERNOON TEMPERATURES IN THE LOWER TO MID 90S.
ISOLATED EVENING THUNDERSTORMS CANNOT BE RULED OUT AS THE MODELS ARE
DEPICTING A WEAK SURFACE BOUNDARY CLOSE BY. THERE IS SOME
UNCERTAINTY WITH REGARDS TO THE EVOLUTION OF THE LARGE SCALE PATTERN
BY TUESDAY AND WEDNESDAY OF NEXT WEEK AND THEREAFTER. THE ECMWF AND
GEM PROGRESS THE UPPER-LEVEL TROUGH INTO CALIFORNIA/NEVADA AREA BY
WEDNESDAY WHILE THE GFS PROGRESSES THE TROUGH INTO THE NORTHERN
ROCKIES AND WESTERN CANADA. BUT ALL THREE OF THESE MODELS MAINTAIN
UPPER-LEVEL RIDGING ACROSS THE PLAINS THROUGH WEDNESDAY. HOWEVER,
THE GFS AND ECMWF SHOW PRECIPITATION IN THE MIDDLE OF THE RIDGE AXIS
EACH DAY, POSSIBLY AS A RESULT OF DAYTIME HEATING AND WEAK CAPPING.
ALSO, THE ECMWF HINTS AT A PLUME OF MID-LEVEL MOISTURE PROGRESSING
FROM THE TROPICS INTO WESTERN KANSAS, AND THIS COULD ALSO RESULT IN
PRECIPITATION EVEN IN THE UPPER-LEVEL RIDGE AXIS. DESPITE THE
UPPER-LEVEL RIDGING, AFTERNOON TEMPERATURES COULD BE HELD DOWN INTO
THE UPPER 80S TO LOWER 90S TUESDAY BY CLOUDS AND PRECIPITATION IF
THIS MOIST SCENARIO ACTUALLY PANS OUT. SEVERE WEATHER CHANCES LOOK
MINIMAL DUE TO THE WEAK WINDS THROUGHOUT THE TROPOSPHERE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1236 PM CDT WED MAY 30 2012
STRONG TO SEVERE THUNDERSTORMS WILL AFFECT SOUTHWEST KANSAS LATE
THIS AFTERNOON INTO THE EVENING HOURS. THE GREATEST IMPACTS WILL BE
FROM ROUGHLY 22Z TO 03Z TIME FRAME. THE TAFS AT GCK AND HYS WILL
REFLECT VICINITY THUNDER BUT WILL GO WITH VICINITY THUNDER AND A
TEMPO PREVAILING THUNDER AT DDC AS THE PROBABILITY OF IMPACT AT DDC
APPEARS TO BE HIGHER BASED ON NUMEROUS HIGH RESOLUTION SIMULATED
REFLECTIVITY RUNS AND OBSERVATIONS OF TEMPERATURE/DEWPOINT/WIND AT
THE SURFACE FITTING THE SHORT-TERM MODEL RUNS. LATER TONIGHT AS THE
MAIN COMPLEX OF SEVERE WEATHER SHIFTS OUT OF THE AREA...ISOLATED TO
WIDELY SCATTERED SHOWERS/THUNDERSTORMS MAY IMPACT SOUTHWEST KANSAS
THROUGH THE NIGHT...BUT THIS IS A LOW PROBABILITY AND WILL NOT
INCLUDE IN THE TAFS. SCATTERED TO BROKEN 2000-3000 FOOT STRATUS
WILL LIKELY PERSIST THROUGH THE NIGHT WITH NORTH-NORTHEAST WINDS
INCREASING 15 TO 20 KNOTS (HIGHER GUSTS AT TIMES).
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 54 72 47 83 / 80 10 10 20
GCK 52 72 47 84 / 60 10 10 20
EHA 54 76 50 89 / 30 10 10 10
LBL 53 75 49 87 / 50 10 10 10
HYS 52 69 46 78 / 70 10 20 20
P28 59 72 48 78 / 90 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS WICHITA KS
204 PM CDT WED MAY 30 2012
.UPDATE...
BUMPED TEMPERATURES UP A FEW DEGREES AS LOW LEVEL MOISTURE HAS BEEN
SLIGHTLY SLOWER TO ARRIVE WITH PLENTY OF INSOLATION ACROSS MUCH OF
SOUTH CENTRAL KANSAS. DEEP MOIST CONVECTION IS STILL EXPECTED TO
DEVELOP AS THE CAP WEAKENS WITH THE APPROACHING SHORT WAVE TROUGH.
ANOTHER ROUND OF THUNDERSTORMS MAY BE POSSIBLE ALONG THE ADVANCING
COLD FRONT LATER THIS EVENING/TONIGHT. SHEAR/CAPE PROFILES
CONTINUE TO SUPPORT SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND
LARGE HAIL THE PRIMARY THREATS.
&&
.AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAINTAINED VFR THROUGH THE TAF PERIOD ACROSS THE AREA WITH VCTS
MENTIONED ACROSS CENTRAL KANSAS THIS AFTERNOON INTO THE EARLY
EVENING HOURS GRADUALLY SPREADING SOUTH AND EAST ACROSS SOUTH
CENTRAL AND SOUTHEAST KANSAS TOWARD MORNING. ALTHOUGH WITH MORE
WIDESPREAD COVERAGE OF SHOWERS AND THUNDERSTORMS...MVFR CIGS MAY
BE MORE PREVALENT TOWARD MORNING ESPECIALLY ACROSS SOUTHEAST
KANSAS.
&&
.PREV DISCUSSION... /ISSUED 650 AM CDT WED MAY 30 2012/
AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN AVIATION CONCERN WILL BE CONVECTIVE TRENDS TODAY THROUGH THE
EVENING HOURS.
OVERNIGHT CONVECTION ACROSS OK HAS MADE IT DIFFICULT TO FIND THE
WARM FRONT WITH BEST GUESS IS THAT IT IS IN BETWEEN THE OK-KS BORDER
AND KOKC. MOISTURE IS EXPECTED TO GRADUALLY LIFT NORTH TODAY ALONG
WITH THE WARM FRONT. AT THE SAME TIME AN UPPER LEVEL WAVE WILL MOVE
OUT OF THE NORTHERN ROCKIES AND INTO THE CENTRAL PLAINS. RIGHT NOW
GOING WITH THE THINKING THAT STORMS WILL DEVELOP OVER WEST-CENTRAL
KS BY AROUND 20Z AS THE BETTER MOISTURE INTERACTS WITH THE UPPER
WAVE. THIS ACTIVITY SHOULD THEN TRACK SOUTHEAST INTO THE EVENING
HOURS...AFFECTING MUCH OF THE FORECAST AREA. SEVERE STORMS WILL BE
POSSIBLE WITH THIS ACTIVITY.
THE COLD FRONT IS EXPECTED TO ENTER CENTRAL KS AFTER 06Z WHICH WILL
FLIP WINDS AROUND TO THE NORTH AND ALSO PROVIDE SOME MVFR CIGS.
LAWSON
PREV DISCUSSION... /ISSUED 330 AM CDT WED MAY 30 2012/
DISCUSSION...
FORECAST HIGHLIGHTS INCLUDE THUNDERSTORM CHANCES TODAY &
TONIGHT...MUCH COOLER TEMPERATURES FOR THU-FRI...AND A WARMING TREND
WEEKEND AND BEYOND.
LOW CONFIDENCE IN OPERATIONAL MODELS FOR TODAY-TONIGHT...AS THEY
HAVE GREATLY STRUGGLED WITH PLACEMENT AND MAGNITUDE OF
MOISTURE/INSTABILITY PROGS THE PAST FEW DAYS. AM TENDING TO SIDE
WITH A 06Z NAM...RUC...HRRR AND NSSL WRF BLEND...WHICH HOLDS OFF
MOST PRECIPITATION UNTIL AFTERNOON. THIS MAKES THE MOST SENSE GIVEN
BRUNT OF INSTABILITY HAS BEEN SHUNTED SOUTH DUE TO WIDESPREAD
OVERNIGHT CONVECTION SCOURING OUT AIRMASS OVER OK. HOWEVER...DID
HOLD ONTO SOME LOW POPS THIS MORNING TO ACCOUNT FOR POSSIBLE
HIT-AND-MISS ISOLATED THUNDERSTORM ACTIVITY FORMING ALONG STALLED
850-700MB BAROCLINIC ZONE ORIENTED NW-SE ACROSS KS.
BY THIS AFTERNOON...THINKING STORM COVERAGE SHOULD GRADUALLY
INCREASE OVER THE HIGH PLAINS...AS AN ELONGATED MID/UPPER TROUGH
CURRENTLY OVER THE ROCKIES APPROACHES FROM THE WEST...INTERACTING
WITH AN INCREASINGLY MOIST/UNSTABLE LOW-LEVEL AIRMASS. THIS ACTIVITY
SHOULD THEN DIVE SOUTHEAST ACROSS THE AREA THROUGH THE
AFTERNOON/EVENING ALONG NORTHERN FRINGE OF STOUT 700MB TEMPERATURES.
THINKING SEVERE THUNDERSTORMS CAPABLE OF HAIL/WIND WILL BE POSSIBLE
GIVEN INCREASINGLY MODEST/STRONG INSTABILITY (POSSIBLY MAINLY
ELEVATED) AND DECENT DEEP LAYER SHEAR. HOWEVER...THINK THE "HIGHER
END" SEVERE WEATHER WILL BE CONFINED TO TX/OK WHERE BEST SFC-BASED
INSTABILITY WILL BE CO-LOCATED WITH OLD OUTFLOW BOUNDARY/DRYLINE
INTERSECTIONS. THEREFORE...WILL REMOVE "CATEGORY 4" FROM HAZARDOUS
WEATHER OUTLOOK. AFTER THIS INITIAL ROUND OF STORMS...ANOTHER ROUND
OF SHOWERS/THUNDERSTORMS SHOULD ROLL SOUTHEAST ACROSS THE REGION
LATER TONIGHT ASSOCIATED WITH THE PARENT STRONG SHORTWAVE AND
ASSOCIATED STRONG COLD FRONT. THE SEVERITY OF THIS ACTIVITY MAY BE
TEMPERED THOUGH DUE TO PREVIOUS ACTIVITY ACTING TO STABILIZE THE
AIRMASS ACROSS THE AREA.
MUCH COOLER WEATHER ANTICIPATED FOR THU-FRI IN WAKE OF THE COLD
FRONT...ALONG WITH STOUT NORTH WINDS THU. FOR FRIDAY...SUBTLE
MID/UPPER ENERGY DIVING SOUTHEAST IN FAST NORTHWEST FLOW ALOFT MAY
RESULT IN ISOLATED/WIDELY SCATTERED ELEVATED
SHOWERS/THUNDERSTORMS...AS 850-700MB WARM/MOIST ADVECTION INCREASES.
GFS AND ECMWF ARE BOTH NOW HINTING AT THIS. ONLY WENT WITH SLIGHT
CHANCE POPS FOR NOW. LIMITED INSTABILITY SHOULD PRECLUDE SEVERE
WEATHER.
PER MEDIUM RANGE CONSENSUS...A GENERAL WARMING TREND IS ANTICIPATED
FOR THE WEEKEND AND BEYOND. ADDITIONALLY...HIT-AND-MISS CHANCES FOR
ISOLATED THUNDERSTORMS WILL BE POSSIBLE FROM THE WEEKEND AND BEYOND
GIVEN VARIOUS MODEL PROGS OF SUBTLE MID-UPPER ENERGY AND
MOIST/UNSTABLE CONDITIONS. HOWEVER...CONFIDENCE REMAINS VERY LOW
REGARDING DETAILS OF TIMING/COVERAGE. ALL-IN-ALL IT APPEARS THE
THREAT FOR WIDESPREAD SEVERE WEATHER IS LOW.
KLEINSASSER
AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN HAZARD: THUNDERSTORM POTENTIAL.
WILL KEEP A MENTION OF TS AT HUT...ICT...AND CNU FOR A FEW HOURS
OVERNIGHT GIVEN CURRENT SCATTERED TS ACROSS AREA. ACTIVITY SEEMS
TO BE OCCURRING IN WEAK ISENTROPIC ASCENT NEAR AND NORTH OF WARM
FRONT. HRRR HAS THIS CONVECTION PUSHING EAST OUT OF AREA AROUND
09-10Z. MODEL SIGNALS REMAIN FAIRLY CONSISTENT SHOWING AN MCS
DEVELOPING WEDNESDAY MORNING TO OUR NORTHWEST OVER NEBRASKA AND
NORTHWEST KS...THEN MOVING SOUTHEASTWARD ACROSS CENTRAL/SOUTHEAST
KS INTO WED PM. THERE MAY BE A SEVERAL HOUR BREAK BEHIND THIS MCS.
THEN ADDITIONAL THUNDERSTORMS APPEAR POSSIBLE WEDNESDAY NIGHT WITH
THE COLD FRONT AND MAIN UPPER TROUGH COMING OUT INTO THE PLAINS.
JMC
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 59 71 49 72 / 70 10 10 20
HUTCHINSON 56 70 48 73 / 70 10 10 20
NEWTON 56 69 48 72 / 70 10 10 20
ELDORADO 58 70 48 71 / 70 10 10 20
WINFIELD-KWLD 61 72 50 72 / 70 10 10 20
RUSSELL 52 69 47 74 / 70 10 10 20
GREAT BEND 53 70 47 74 / 70 10 10 20
SALINA 55 69 47 73 / 70 10 10 20
MCPHERSON 55 69 47 73 / 70 10 10 20
COFFEYVILLE 64 72 50 69 / 70 30 10 20
CHANUTE 61 70 48 69 / 70 30 10 20
IOLA 61 70 48 68 / 70 30 10 20
PARSONS-KPPF 63 71 50 69 / 70 30 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
122 PM CDT WED MAY 30 2012
...UPDATED SYNOPSIS AND SHORT TERM SECTIONS...
.SYNOPSIS...
ISSUED AT 120 PM CDT WED MAY 30 2012
AS OF 17Z...AN AXIS OF 62-64F DEWPOINTS WERE OBSERVED ACROSS THE
EASTERN TEXAS PANHANDLE AND ADJACENT EXTREME WESTERN OKLAHOMA ALONG
AND WEST OF THE REMNANT OUTFLOW BOUNDARY FROM LAST NIGHTS OKLAHOMA
THUNDERSTORM COMPLEX. TEMPERATURES WERE WARMING INTO THE LOWER 80S
ACROSS MUCH OF SOUTHWEST KANSAS ON A SOUTHEAST WIND...ALLOWING
SURFACE-BASED CAPE VALUES TO EXCEED 2000 J/KG ALONG THE MOISTURE
AXIS. VISIBLE SATELLITE SHOWED A FAIRLY LARGE AREA OF STRATOCUMULUS
CLOUDS WITHIN THE MOISTURE AXIS ACROSS MUCH OF SOUTHWEST KANSAS. A
LOOK OUT THE WINDOW HERE AT THE WEATHER OFFICE CONFIRMED FAIRLY FLAT
LOOKING CUMULUS AS OF 1755 UTC. A WEAK BUT IMPORTANT SURFACE
BOUNDARY WAS OBSERVED FROM JUST SOUTH OF RUSSELL, KS
WEST-NORTHWESTWARD TO NEAR GOVE, KS. TEMPERATURES NORTH OF THIS
BOUNDARY WERE STILL HANGING IN THE LOWER 70S...WITH TEMPERATURES
RISING INTO THE LOWER 80S SOUTH OF THE BOUNDARY ACROSS MUCH OF
SOUTHEST KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 120 PM CDT WED MAY 30 2012
THE HRRR AND RAP MODELS HAVE SHOWN A PERSISTENT CONVECTIVE
INITIATION SIGNAL ACROSS WEST CENTRAL OR SOUTHWEST KANSAS...ROUGHLY
IN AN AREA BOUNDED BY KALVESTA-GOVE-NESS CITY-KALVESTA...BY 20 TO
21Z. THIS WOULD SEEM TO MATCH THE LOCATION OF WHERE THE BOUNDARY
IS...ALTHOUGH IS A BIT FARTHER SOUTH. IT WOULD SEEM THE BEST AREA
FOR CONVECTIVE INITIATION WOULD BE JUST NORTH OF WHERE THE LATEST
HRRR RUNS HAVE IT...BUT EITHER WAY CONVECTIVE INITIATION SHOULD
OCCUR BY NO LATER THAN 22Z NORTH OF HIGHWAY 50 AND ALONG/SOUTH OF
INTERSTATE 70 IN SOUTHWEST/WEST-CENTRAL KANSAS. THE EARLY STAGE OF
CONVECTIVE MODE SHOULD BE SUPERCELLULAR WITH SURFACE-BASED CAPE
CONTINUING TO INCREASE ABOVE 3000 J/KG AND A SUBSTANTIAL AMOUNT OF
DEEP LAYER SHEAR TO SUPPORT VIGOROUS SUPERCELL THUNDERSTORMS.
SUPERCELL STORM MOTION WILL BE SOUTHEAST AT AROUND 20 TO 25 KNOTS
(NON SUPERCELL STORM MOTION BEING MORE EASTERLY). THE STORM
PREDICTION CENTER (SPC) PROBABILISTIC HAIL AND WIND ARE VERY HIGH
ACROSS MUCH OF THE DDC FORECAST AREA...INCLUDING ALL POINTS SOUTH OF
HIGHWAY 4 AND EAST OF HIGHWAY 83. THE SPC PROBABILISTIC SEVERE
WEATHER THREATS LOOK PRETTY GOOD AND AGREE ON JUST ABOUT ALL
ACCOUNTS. THE ONLY THING I QUESTION IS THE TORNADO POTENTIAL...AS
CONVECTIVE MODE AFTER A FEW HOURS MAY TRANSITION MORE TO A
QUASI-LINEAR SIGNIFICANT SEVERE EPISODE (DAMAGING TO DESTRUCTIVE
WIND POTENTIAL 80+ MPH). THIS MAY NOT OCCUR UNTIL LATER THIS
EVENING AS THE SEVERE WEATHER EVENT SHIFTS INTO OKLAHOMA. IF THE
SUPERCELL PHASE CAN LAST SEVERAL HOURS THEN THE TORNADO POTENTIAL
WILL DEFINITELY BE ENHANCED...AND FOR THAT REASON THE 10 PERCENT
TORNADO POTENTIAL (PROB OF A TORNADO WITHIN 25 MILES OF A POINT)
DOES LOOK JUSTIFIED FOR AREAS GENERALLY SOUTHEAST OF A LIBERAL TO
JETMORE TO LARNED LINE. DURING THE EVENING HOURS...THE SEVERE
WEATHER THREAT WILL DIMINISH FROM NORTH TO SOUTH AS THE MAIN AREA
SHIFTS INTO NORTHERN OKLAHOMA...HOWEVER WILL MAINTAIN SOME 20-50
POPS IN THE SOUTHEAST HALF OF THE FORECAST AREA THROUGH THE 06-09Z
TIME FRAME AS ADDITIONAL STORMS MAY DEVELOP IN THE WAKE OF THE
PRIMARY ROUND. ANYTHING DEVELOPING AFTER THE PRIMARY ROUND WILL
HAVE MUCH LESS INSTABILITY TO WORK WITH AND THE SEVERE WEATHER
THREAT SHOULD BE RATHER LOW.
THE REST OF THE FORECAST FOR LATE TONIGHT AND TOMORROW WAS
ESSENTIALLY UNCHANGED AS SUBSIDENCE AND DRIER AIR MOVES IN ON
NORTHEAST WINDS. TEMPERATURES WILL STRUGGLE TO ESCAPE THE LOWER 70S
OVER MUCH OF SOUTHWEST KANSAS ON THURSDAY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 AM CDT WED MAY 30 2012
BY FRIDAY, THE CLOSED MID LEVEL CIRCULATION WILL BE CENTERED OVER
THE UPPER MISSISSIPPI VALLEY WITH A VERY BROAD NORTHWESTERLY
ORIENTED UPPER JET EXTENDING FROM THE PACIFIC NORTHWEST, THROUGH THE
NORTHERN AND CENTRAL HIGH PLAINS REGIONS. THE SURFACE PATTERN WILL
FEATURE ABOUT A 1015-1017 MB SURFACE HIGH THAT WILL DROP FROM THE
DAKOTAS ON THURSDAY INTO THE CENTRAL PLAINS ON THURSDAY NIGHT. THIS
REPRESENTS A SOMEWHAT COOL NORTHEASTERLY SURFACE FLOW PATTERN FOR
SOUTHWEST KANSAS. THE GFS DOES PAINT LIGHT QPF WHICH REALLY JUST
REPRESENTS THE MODEL ATTEMPTING TO TURN OVER INSTABILITY, IN THE
WESTERN POSITIONS OF THE AREA THURSDAY EVENING. HOWEVER, IT SEEMS
MORE PROBABLE NO THUNDERSTORMS MIGHT BE EXPECTED, ESPECIALLY GIVEN
THAT THE SUBSIDENT THERMALLY INDIRECT CONVERGENT RIGHT FRONT
QUADRANT OF THE INCOMING JET SHOULD BE FOCUSED OVER WESTERN KANSAS.
FROM THURSDAY NIGHT INTO FRIDAY, THE SURFACE HIGH PRESSURE SLIDES
RAPIDLY INTO THE SOUTHERN PLAINS. AS A RESULT A STOUT SURFACE
PRESSURE GRADIENT DEVELOPS OVER WESTERN KANSAS BY FRIDAY AFTERNOON,
WHICH SHOULD PRODUCE AT LEAST BREEZY SOUTHERLY WINDS. DURING THE
TIMEFRAME FROM FRIDAY MORNING INTO FRIDAY NIGHT, BOTH THE ECMWF AND
GFS PRODUCE A SWATH OF QPF SLIDING SOUTH ACROSS NORTHERN AND CENTRAL
KANSAS. THERE IS CONSIDERABLE DEFORMATION IN THE MID LEVEL HEIGHT
FIELD AND SOME INDICATION OF A WEAK SHORTWAVE MOVING INTO THE AREA.
HOWEVER, BY CONTRAST, THE NAM MODEL SEEMS TO INDICATE CONVECTION
DEVELOPED DIURNALLY ALONG A SURFACE CONVERGENCE AXIS/ MOISTURE
DISCONTINUITY LATE IN THE DAY. ISOLATED STORMS SEEM ALL THAT MIGHT
BE EXPECTED. WITH THESE DIFFERENT SOLUTIONS, THERE IS PLENTY OF
UNCERTAINTY IN THE EXPECTED MESOSCALE DETAILS FOR LATE FRIDAY.
ON SATURDAY, THE UPPER RIDGE BEGINS TO BUILD SLIGHTLY FARTHER EAST.
THEREFORE A SLIGHT INCREASE IN TEMPERATURES CAN BE EXPECTED WITH
INCREASING THICKNESSES. ECMWF/GFS ELUDE TO THE AREA FROM SOUTH
CENTRAL KANSAS INTO OKLAHOMA AS BEING POTENTIALLY CONVECTIVELY
ACTIVE IN A ZONE OF HIGHER THETA-E. LESSER CONFIDENCE EXISTS WITH
RESPECT TO ANY STORM CHANCES BEYOND THIS POINT. THE MODELS BEGIN TO
TAKE ON A FLAT RIDGE PATTERN INTO SUNDAY WITH A NOISY SIGNAL OF
EMBEDDED COMPACT SHORTWAVE ENERGY AROUND THE AREA. GFS ENSEMBLE
TEMPERATURES WARM TO NEAR 90S DEGREES BY SUNDAY AFTERNOON, BUT STILL
INDICATE AROUND A 10 DEGREE SPREAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1236 PM CDT WED MAY 30 2012
STRONG TO SEVERE THUNDERSTORMS WILL AFFECT SOUTHWEST KANSAS LATE
THIS AFTERNOON INTO THE EVENING HOURS. THE GREATEST IMPACTS WILL BE
FROM ROUGHLY 22Z TO 03Z TIME FRAME. THE TAFS AT GCK AND HYS WILL
REFLECT VICINITY THUNDER BUT WILL GO WITH VICINITY THUNDER AND A
TEMPO PREVAILING THUNDER AT DDC AS THE PROBABILITY OF IMPACT AT DDC
APPEARS TO BE HIGHER BASED ON NUMEROUS HIGH RESOLUTION SIMULATED
REFLECTIVITY RUNS AND OBSERVATIONS OF TEMPERATURE/DEWPOINT/WIND AT
THE SURFACE FITTING THE SHORT-TERM MODEL RUNS. LATER TONIGHT AS THE
MAIN COMPLEX OF SEVERE WEATHER SHIFTS OUT OF THE AREA...ISOLATED TO
WIDELY SCATTERED SHOWERS/THUNDERSTORMS MAY IMPACT SOUTHWEST KANSAS
THROUGH THE NIGHT...BUT THIS IS A LOW PROBABILITY AND WILL NOT
INCLUDE IN THE TAFS. SCATTERED TO BROKEN 2000-3000 FOOT STRATUS
WILL LIKELY PERSIST THROUGH THE NIGHT WITH NORTH-NORTHEAST WINDS
INCREASING 15 TO 20 KNOTS (HIGHER GUSTS AT TIMES).
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 54 72 47 83 / 80 10 0 10
GCK 52 72 47 84 / 60 10 0 20
EHA 54 76 50 89 / 30 10 0 20
LBL 53 75 49 87 / 50 10 0 20
HYS 52 69 46 78 / 70 10 10 20
P28 59 72 48 78 / 90 10 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...RUSSELL
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1237 PM CDT WED MAY 30 2012
...UPDATED AVIATION SECTION FOR 18Z TAFS...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 330 AM CDT WED MAY 30 2012
FOR THE NEAR TERM, BASED ON THE THE NAM, RUC AND HRRR SHORTER TERM MODELS,
I LOWERED POPS CONSIDERABLY PRIOR TO 18Z TODAY, AND LOWERED QPF AS
WELL. THERE IS A SHORT WAVE EVIDENT IN THE 00Z UPPER AIR ANALYSIS
AND LESS EVIDENT IN THE WATER VAPOR LOOP, AND THIS WAVE WILL COME
DOWN INTO OUR FORECAST AREA LATE TODAY. WITH THAT SAID, THERE
APPEARS ONLY TO BE SLIGHT OVER RUNNING CONDITIONS THIS MORNING AND
JUST SLIGHT UPSLOPE FLOW. SO CLOUDS MAY INCREASE THIS MORNING IN
THE STRATOCU LEVEL, BUT THE INSTABILITY DOES NOT SEEM STRONG
ENOUGH FOR ANY CONVECTION. THE FRONT DOWN IN OKLAHOMA WILL NUDGE
NORTH BY THIS AFTERNOON, AND THE OVER RUNNING OF THE 850MB FLOW
FROM THE SOUTH WILL COLLIDE WITH THE AFOREMENTIONED SHORT WAVE
TRAVELING SOUTHEASTWARD. THESE CONDITIONS WILL SET UP A 1500-1600
CAPE SITUATION ACROSS OUR EASTERN CWA, AND THE SURFACE HEATING BY
THEN WILL LEAD TO MORE INSTABILITY. HAVE KEPT THE LIKELY 60
PERCENT POPS GOING AFTER 21Z IN OUR SOUTHEAST AND EASTERN ZONES,
SOUTHEAST OF A LINE FROM LARNED TO MEADE. IN THE ZONE WORDING, I
WILL HAVE POSSIBLE SEVERE WORDING WITH THE MENTION OF LARGE HAIL
AND DAMAGING WINDS. QPF IS TRICKY, BUT FORECAST SOUNDINGS IN OUR
SOUTHEAST ZONES WOULD PLACE UP TO 1.22 PW IN THE GREENSBURG TO
MEDICINE LODGE AREAS. DO NOT EXPECT THAT AMOUNT IN A BASIN-WIDE
AVERAGE, SO WENT WITH 0.41 INCH INSTEAD. BUMPED HIGH TEMPERATURES
UP JUST A FEW DEGREES TODAY, THINKING THE DELAYED PRECIPITATION
WILL GIVE THE LIMITED SUN MORE TIME TO WARM THE SURFACE UP.
TONIGHT, THERE WILL BE A CHANCE FOR GENERAL STORMS TO OCCUR IN THE
WRAP AROUND SECTION OF THE UPPER WAVE. DO NOT EXPECT TONIGHT`S
STORMS TO BE SEVERE, BUT MORE OF A GENERAL THUNDERSTORM NATURE.
ONLY LIGHT QPF AMOUNTS ARE EXPECTED AFTER MIDNIGHT, WHEN POPS WILL
DIMINISH TO 20 TO 30 PERCENT. MINIMUM TEMPERATURES WILL BE IN THE
UPPER 40S FROM SYRACUSE TO SCOTT CITY, BUT RANGE TO THE UPPER 50S
DOWN IN THE MEDICINE LODGE AREA. WINDS SHOULD BE FROM THE
NORTHEAST AT 10 TO 20 MPH EARLY TONIGHT, THEN SHIFT MORE NORTHERLY
AT 10 TO 15 MPH AFTER MIDNIGHT TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 AM CDT WED MAY 30 2012
BY FRIDAY, THE CLOSED MID LEVEL CIRCULATION WILL BE CENTERED OVER
THE UPPER MISSISSIPPI VALLEY WITH A VERY BROAD NORTHWESTERLY
ORIENTED UPPER JET EXTENDING FROM THE PACIFIC NORTHWEST, THROUGH THE
NORTHERN AND CENTRAL HIGH PLAINS REGIONS. THE SURFACE PATTERN WILL
FEATURE ABOUT A 1015-1017 MB SURFACE HIGH THAT WILL DROP FROM THE
DAKOTAS ON THURSDAY INTO THE CENTRAL PLAINS ON THURSDAY NIGHT. THIS
REPRESENTS A SOMEWHAT COOL NORTHEASTERLY SURFACE FLOW PATTERN FOR
SOUTHWEST KANSAS. THE GFS DOES PAINT LIGHT QPF WHICH REALLY JUST
REPRESENTS THE MODEL ATTEMPTING TO TURN OVER INSTABILITY, IN THE
WESTERN POSITIONS OF THE AREA THURSDAY EVENING. HOWEVER, IT SEEMS
MORE PROBABLE NO THUNDERSTORMS MIGHT BE EXPECTED, ESPECIALLY GIVEN
THAT THE SUBSIDENT THERMALLY INDIRECT CONVERGENT RIGHT FRONT
QUADRANT OF THE INCOMING JET SHOULD BE FOCUSED OVER WESTERN KANSAS.
FROM THURSDAY NIGHT INTO FRIDAY, THE SURFACE HIGH PRESSURE SLIDES
RAPIDLY INTO THE SOUTHERN PLAINS. AS A RESULT A STOUT SURFACE
PRESSURE GRADIENT DEVELOPS OVER WESTERN KANSAS BY FRIDAY AFTERNOON,
WHICH SHOULD PRODUCE AT LEAST BREEZY SOUTHERLY WINDS. DURING THE
TIMEFRAME FROM FRIDAY MORNING INTO FRIDAY NIGHT, BOTH THE ECMWF AND
GFS PRODUCE A SWATH OF QPF SLIDING SOUTH ACROSS NORTHERN AND CENTRAL
KANSAS. THERE IS CONSIDERABLE DEFORMATION IN THE MID LEVEL HEIGHT
FIELD AND SOME INDICATION OF A WEAK SHORTWAVE MOVING INTO THE AREA.
HOWEVER, BY CONTRAST, THE NAM MODEL SEEMS TO INDICATE CONVECTION
DEVELOPED DIURNALLY ALONG A SURFACE CONVERGENCE AXIS/ MOISTURE
DISCONTINUITY LATE IN THE DAY. ISOLATED STORMS SEEM ALL THAT MIGHT
BE EXPECTED. WITH THESE DIFFERENT SOLUTIONS, THERE IS PLENTY OF
UNCERTAINTY IN THE EXPECTED MESOSCALE DETAILS FOR LATE FRIDAY.
ON SATURDAY, THE UPPER RIDGE BEGINS TO BUILD SLIGHTLY FARTHER EAST.
THEREFORE A SLIGHT INCREASE IN TEMPERATURES CAN BE EXPECTED WITH
INCREASING THICKNESSES. ECMWF/GFS ELUDE TO THE AREA FROM SOUTH
CENTRAL KANSAS INTO OKLAHOMA AS BEING POTENTIALLY CONVECTIVELY
ACTIVE IN A ZONE OF HIGHER THETA-E. LESSER CONFIDENCE EXISTS WITH
RESPECT TO ANY STORM CHANCES BEYOND THIS POINT. THE MODELS BEGIN TO
TAKE ON A FLAT RIDGE PATTERN INTO SUNDAY WITH A NOISY SIGNAL OF
EMBEDDED COMPACT SHORTWAVE ENERGY AROUND THE AREA. GFS ENSEMBLE
TEMPERATURES WARM TO NEAR 90S DEGREES BY SUNDAY AFTERNOON, BUT STILL
INDICATE AROUND A 10 DEGREE SPREAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1236 PM CDT WED MAY 30 2012
STRONG TO SEVERE THUNDERSTORMS WILL AFFECT SOUTHWEST KANSAS LATE
THIS AFTERNOON INTO THE EVENING HOURS. THE GREATEST IMPACTS WILL BE
FROM ROUGHLY 22Z TO 03Z TIME FRAME. THE TAFS AT GCK AND HYS WILL
REFLECT VICINITY THUNDER BUT WILL GO WITH VICINITY THUNDER AND A
TEMPO PREVAILING THUNDER AT DDC AS THE PROBABILITY OF IMPACT AT DDC
APPEARS TO BE HIGHER BASED ON NUMEROUS HIGH RESOLUTION SIMULATED
REFLECTIVITY RUNS AND OBSERVATIONS OF TEMPERATURE/DEWPOINT/WIND AT
THE SURFACE FITTING THE SHORT-TERM MODEL RUNS. LATER TONIGHT AS THE
MAIN COMPLEX OF SEVERE WEATHER SHIFTS OUT OF THE AREA...ISOLATED TO
WIDELY SCATTERED SHOWERS/THUNDERSTORMS MAY IMPACT SOUTHWEST KANSAS
THROUGH THE NIGHT...BUT THIS IS A LOW PROBABILITY AND WILL NOT
INCLUDE IN THE TAFS. SCATTERED TO BROKEN 2000-3000 FOOT STRATUS
WILL LIKELY PERSIST THROUGH THE NIGHT WITH NORTH-NORTHEAST WINDS
INCREASING 15 TO 20 KNOTS (HIGHER GUSTS AT TIMES).
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 85 54 72 47 / 60 70 10 0
GCK 85 52 72 47 / 50 50 10 0
EHA 85 54 76 50 / 30 40 10 0
LBL 88 53 75 49 / 40 50 10 0
HYS 79 52 69 46 / 70 70 10 10
P28 88 59 72 48 / 80 70 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
842 AM CDT WED MAY 30 2012
...SIGNIFICANT SEVERE WEATHER POSSIBLE ACROSS SOUTHWEST KANSAS TODAY...
.UPDATE...
ISSUED AT 834 AM CDT WED MAY 30 2012
A QUICK UPDATE TO THE FORECAST WAS MADE MAINLY IN THE TEMPERATURES
FOR TODAY. SINCE THUNDERSTORM ACTIVITY WAS NOT REALIZED THIS
MORNING ACROSS THE REGION...TEMPERATURES WILL WARM UP CONSIDERABLY
MORE THAN PREVIOUS FORECAST. RELIABLE NEAR-TERM HIGH RESOLUTION
MODELS ARE INHIBITING CONVECTION UNTIL AT LEAST MIDDAY OR EARLY
AFTERNOON ACROSS SOUTHWEST KANSAS...WHICH WILL ALLOW SIGNIFICANT
AMOUNTS OF INSTABILITY TO DEVELOP AS A POOL OF DEEP MOISTURE
LINGERING TO THE SOUTH OF SOUTHWEST KANSAS STREAMS NORTHWARD ON
INCREASING SOUTHEAST WINDS. SURFACE BASED CAPE OF 3500-4500 J/KG
WILL DEVELOP BY MID AFTERNOON AS THE INITIAL STORMS DEVELOP ACROSS
PORTIONS OF WEST-CENTRAL KANSAS. THE SEVERE WEATHER THREAT MAY
BE REALIZED FARTHER WEST AS THUNDERSTORM OUTFLOW FROM THE OKLAHOMA
STORMS DURING THE OVERNIGHT HOURS HAVE HELPED PUSH SOME OF THE
DEEPER, RICHER MOISTURE A BIT FARTHER TO THE WEST THAN SOME OF THE
MODELS ARE SUGGESTING. THIS CAN BE SEEN ON VISIBLE SATELLITE THIS
MORNING AS STRATUS EXTENDS FROM THE TEXAS PANHANDLE NORTHWARD
THROUGH FAR SOUTHWEST KANSAS. AN ADJUSTMENT OF THE HIGHEST POPS
WESTWARD MAY BE NECESSARY FOR LATE THIS AFTERNOON/EVENING.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 330 AM CDT WED MAY 30 2012
FOR THE NEAR TERM, BASED ON THE THE NAM, RUC AND HRRR SHORTER TERM MODELS,
I LOWERED POPS CONSIDERABLY PRIOR TO 18Z TODAY, AND LOWERED QPF AS
WELL. THERE IS A SHORT WAVE EVIDENT IN THE 00Z UPPER AIR ANALYSIS
AND LESS EVIDENT IN THE WATER VAPOR LOOP, AND THIS WAVE WILL COME
DOWN INTO OUR FORECAST AREA LATE TODAY. WITH THAT SAID, THERE
APPEARS ONLY TO BE SLIGHT OVER RUNNING CONDITIONS THIS MORNING AND
JUST SLIGHT UPSLOPE FLOW. SO CLOUDS MAY INCREASE THIS MORNING IN
THE STRATOCU LEVEL, BUT THE INSTABILITY DOES NOT SEEM STRONG
ENOUGH FOR ANY CONVECTION. THE FRONT DOWN IN OKLAHOMA WILL NUDGE
NORTH BY THIS AFTERNOON, AND THE OVER RUNNING OF THE 850MB FLOW
FROM THE SOUTH WILL COLLIDE WITH THE AFOREMENTIONED SHORT WAVE
TRAVELING SOUTHEASTWARD. THESE CONDITIONS WILL SET UP A 1500-1600
CAPE SITUATION ACROSS OUR EASTERN CWA, AND THE SURFACE HEATING BY
THEN WILL LEAD TO MORE INSTABILITY. HAVE KEPT THE LIKELY 60
PERCENT POPS GOING AFTER 21Z IN OUR SOUTHEAST AND EASTERN ZONES,
SOUTHEAST OF A LINE FROM LARNED TO MEADE. IN THE ZONE WORDING, I
WILL HAVE POSSIBLE SEVERE WORDING WITH THE MENTION OF LARGE HAIL
AND DAMAGING WINDS. QPF IS TRICKY, BUT FORECAST SOUNDINGS IN OUR
SOUTHEAST ZONES WOULD PLACE UP TO 1.22 PW IN THE GREENSBURG TO
MEDICINE LODGE AREAS. DO NOT EXPECT THAT AMOUNT IN A BASIN-WIDE
AVERAGE, SO WENT WITH 0.41 INCH INSTEAD. BUMPED HIGH TEMPERATURES
UP JUST A FEW DEGREES TODAY, THINKING THE DELAYED PRECIPITATION
WILL GIVE THE LIMITED SUN MORE TIME TO WARM THE SURFACE UP.
TONIGHT, THERE WILL BE A CHANCE FOR GENERAL STORMS TO OCCUR IN THE
WRAP AROUND SECTION OF THE UPPER WAVE. DO NOT EXPECT TONIGHT`S
STORMS TO BE SEVERE, BUT MORE OF A GENERAL THUNDERSTORM NATURE.
ONLY LIGHT QPF AMOUNTS ARE EXPECTED AFTER MIDNIGHT, WHEN POPS WILL
DIMINISH TO 20 TO 30 PERCENT. MINIMUM TEMPERATURES WILL BE IN THE
UPPER 40S FROM SYRACUSE TO SCOTT CITY, BUT RANGE TO THE UPPER 50S
DOWN IN THE MEDICINE LODGE AREA. WINDS SHOULD BE FROM THE
NORTHEAST AT 10 TO 20 MPH EARLY TONIGHT, THEN SHIFT MORE NORTHERLY
AT 10 TO 15 MPH AFTER MIDNIGHT TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 AM CDT WED MAY 30 2012
BY FRIDAY, THE CLOSED MID LEVEL CIRCULATION WILL BE CENTERED OVER
THE UPPER MISSISSIPPI VALLEY WITH A VERY BROAD NORTHWESTERLY
ORIENTED UPPER JET EXTENDING FROM THE PACIFIC NORTHWEST, THROUGH THE
NORTHERN AND CENTRAL HIGH PLAINS REGIONS. THE SURFACE PATTERN WILL
FEATURE ABOUT A 1015-1017 MB SURFACE HIGH THAT WILL DROP FROM THE
DAKOTAS ON THURSDAY INTO THE CENTRAL PLAINS ON THURSDAY NIGHT. THIS
REPRESENTS A SOMEWHAT COOL NORTHEASTERLY SURFACE FLOW PATTERN FOR
SOUTHWEST KANSAS. THE GFS DOES PAINT LIGHT QPF WHICH REALLY JUST
REPRESENTS THE MODEL ATTEMPTING TO TURN OVER INSTABILITY, IN THE
WESTERN POSITIONS OF THE AREA THURSDAY EVENING. HOWEVER, IT SEEMS
MORE PROBABLE NO THUNDERSTORMS MIGHT BE EXPECTED, ESPECIALLY GIVEN
THAT THE SUBSIDENT THERMALLY INDIRECT CONVERGENT RIGHT FRONT
QUADRANT OF THE INCOMING JET SHOULD BE FOCUSED OVER WESTERN KANSAS.
FROM THURSDAY NIGHT INTO FRIDAY, THE SURFACE HIGH PRESSURE SLIDES
RAPIDLY INTO THE SOUTHERN PLAINS. AS A RESULT A STOUT SURFACE
PRESSURE GRADIENT DEVELOPS OVER WESTERN KANSAS BY FRIDAY AFTERNOON,
WHICH SHOULD PRODUCE AT LEAST BREEZY SOUTHERLY WINDS. DURING THE
TIMEFRAME FROM FRIDAY MORNING INTO FRIDAY NIGHT, BOTH THE ECMWF AND
GFS PRODUCE A SWATH OF QPF SLIDING SOUTH ACROSS NORTHERN AND CENTRAL
KANSAS. THERE IS CONSIDERABLE DEFORMATION IN THE MID LEVEL HEIGHT
FIELD AND SOME INDICATION OF A WEAK SHORTWAVE MOVING INTO THE AREA.
HOWEVER, BY CONTRAST, THE NAM MODEL SEEMS TO INDICATE CONVECTION
DEVELOPED DIURNALLY ALONG A SURFACE CONVERGENCE AXIS/ MOISTURE
DISCONTINUITY LATE IN THE DAY. ISOLATED STORMS SEEM ALL THAT MIGHT
BE EXPECTED. WITH THESE DIFFERENT SOLUTIONS, THERE IS PLENTY OF
UNCERTAINTY IN THE EXPECTED MESOSCALE DETAILS FOR LATE FRIDAY.
ON SATURDAY, THE UPPER RIDGE BEGINS TO BUILD SLIGHTLY FARTHER EAST.
THEREFORE A SLIGHT INCREASE IN TEMPERATURES CAN BE EXPECTED WITH
INCREASING THICKNESSES. ECMWF/GFS ELUDE TO THE AREA FROM SOUTH
CENTRAL KANSAS INTO OKLAHOMA AS BEING POTENTIALLY CONVECTIVELY
ACTIVE IN A ZONE OF HIGHER THETA-E. LESSER CONFIDENCE EXISTS WITH
RESPECT TO ANY STORM CHANCES BEYOND THIS POINT. THE MODELS BEGIN TO
TAKE ON A FLAT RIDGE PATTERN INTO SUNDAY WITH A NOISY SIGNAL OF
EMBEDDED COMPACT SHORTWAVE ENERGY AROUND THE AREA. GFS ENSEMBLE
TEMPERATURES WARM TO NEAR 90S DEGREES BY SUNDAY AFTERNOON, BUT STILL
INDICATE AROUND A 10 DEGREE SPREAD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 647 AM CDT WED MAY 30 2012
HIGH PRESSURE OVER THE NORTHERN PLAINS IS AIDING LIGHT EASTERLY
SURFACE FLOW ACROSS WESTERN KANSAS THIS MORNING. DESTABILIZATION OF
THE ATMOSPHERE WILL OCCUR AS STRONG INSOLATION BEGINS THROUGH THE
LATE MORNING AND EARLY AFTERNOON. MODELS TEND TO SUPPORT CONVECTIVE
INITIATION AHEAD OF AN ADVANCING COLD FRONT FRONT NEBRASKA, WITH DEEP
MOIST CONVECTION BECOMING MORE WIDESPREAD TO THE SOUTH ACROSS MUCH
OF CENTRAL KANSAS OVER THE MIDDLE TO LATE AFTERNOON HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 90 54 72 47 / 60 50 0 0
GCK 91 52 72 47 / 50 40 0 0
EHA 89 54 76 50 / 40 40 0 0
LBL 92 53 75 49 / 40 40 0 0
HYS 87 52 69 46 / 70 60 0 10
P28 91 59 72 48 / 80 70 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...UMSCHEID
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS WICHITA KS
650 AM CDT WED MAY 30 2012
.AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN AVIATION CONCERN WILL BE CONVECTIVE TRENDS TODAY THROUGH THE
EVENING HOURS.
OVERNIGHT CONVECTION ACROSS OK HAS MADE IT DIFFICULT TO FIND THE
WARM FRONT WITH BEST GUESS IS THAT IT IS IN BETWEEN THE OK-KS BORDER
AND KOKC. MOISTURE IS EXPECTED TO GRADUALLY LIFT NORTH TODAY ALONG
WITH THE WARM FRONT. AT THE SAME TIME AN UPPER LEVEL WAVE WILL MOVE
OUT OF THE NORTHERN ROCKIES AND INTO THE CENTRAL PLAINS. RIGHT NOW
GOING WITH THE THINKING THAT STORMS WILL DEVELOP OVER WEST-CENTRAL
KS BY AROUND 20Z AS THE BETTER MOISTURE INTERACTS WITH THE UPPER
WAVE. THIS ACTIVITY SHOULD THEN TRACK SOUTHEAST INTO THE EVENING
HOURS...AFFECTING MUCH OF THE FORECAST AREA. SEVERE STORMS WILL BE
POSSIBLE WITH THIS ACTIVITY.
THE COLD FRONT IS EXPECTED TO ENTER CENTRAL KS AFTER 06Z WHICH WILL
FLIP WINDS AROUND TO THE NORTH AND ALSO PROVIDE SOME MVFR CIGS.
LAWSON
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT WED MAY 30 2012/
DISCUSSION...
FORECAST HIGHLIGHTS INCLUDE THUNDERSTORM CHANCES TODAY &
TONIGHT...MUCH COOLER TEMPERATURES FOR THU-FRI...AND A WARMING TREND
WEEKEND AND BEYOND.
LOW CONFIDENCE IN OPERATIONAL MODELS FOR TODAY-TONIGHT...AS THEY
HAVE GREATLY STRUGGLED WITH PLACEMENT AND MAGNITUDE OF
MOISTURE/INSTABILITY PROGS THE PAST FEW DAYS. AM TENDING TO SIDE
WITH A 06Z NAM...RUC...HRRR AND NSSL WRF BLEND...WHICH HOLDS OFF
MOST PRECIPITATION UNTIL AFTERNOON. THIS MAKES THE MOST SENSE GIVEN
BRUNT OF INSTABILITY HAS BEEN SHUNTED SOUTH DUE TO WIDESPREAD
OVERNIGHT CONVECTION SCOURING OUT AIRMASS OVER OK. HOWEVER...DID
HOLD ONTO SOME LOW POPS THIS MORNING TO ACCOUNT FOR POSSIBLE
HIT-AND-MISS ISOLATED THUNDERSTORM ACTIVITY FORMING ALONG STALLED
850-700MB BAROCLINIC ZONE ORIENTED NW-SE ACROSS KS.
BY THIS AFTERNOON...THINKING STORM COVERAGE SHOULD GRADUALLY
INCREASE OVER THE HIGH PLAINS...AS AN ELONGATED MID/UPPER TROUGH
CURRENTLY OVER THE ROCKIES APPROACHES FROM THE WEST...INTERACTING
WITH AN INCREASINGLY MOIST/UNSTABLE LOW-LEVEL AIRMASS. THIS ACTIVITY
SHOULD THEN DIVE SOUTHEAST ACROSS THE AREA THROUGH THE
AFTERNOON/EVENING ALONG NORTHERN FRINGE OF STOUT 700MB TEMPERATURES.
THINKING SEVERE THUNDERSTORMS CAPABLE OF HAIL/WIND WILL BE POSSIBLE
GIVEN INCREASINGLY MODEST/STRONG INSTABILITY (POSSIBLY MAINLY
ELEVATED) AND DECENT DEEP LAYER SHEAR. HOWEVER...THINK THE "HIGHER
END" SEVERE WEATHER WILL BE CONFINED TO TX/OK WHERE BEST SFC-BASED
INSTABILITY WILL BE CO-LOCATED WITH OLD OUTFLOW BOUNDARY/DRYLINE
INTERSECTIONS. THEREFORE...WILL REMOVE "CATEGORY 4" FROM HAZARDOUS
WEATHER OUTLOOK. AFTER THIS INITIAL ROUND OF STORMS...ANOTHER ROUND
OF SHOWERS/THUNDERSTORMS SHOULD ROLL SOUTHEAST ACROSS THE REGION
LATER TONIGHT ASSOCIATED WITH THE PARENT STRONG SHORTWAVE AND
ASSOCIATED STRONG COLD FRONT. THE SEVERITY OF THIS ACTIVITY MAY BE
TEMPERED THOUGH DUE TO PREVIOUS ACTIVITY ACTING TO STABILIZE THE
AIRMASS ACROSS THE AREA.
MUCH COOLER WEATHER ANTICIPATED FOR THU-FRI IN WAKE OF THE COLD
FRONT...ALONG WITH STOUT NORTH WINDS THU. FOR FRIDAY...SUBTLE
MID/UPPER ENERGY DIVING SOUTHEAST IN FAST NORTHWEST FLOW ALOFT MAY
RESULT IN ISOLATED/WIDELY SCATTERED ELEVATED
SHOWERS/THUNDERSTORMS...AS 850-700MB WARM/MOIST ADVECTION INCREASES.
GFS AND ECMWF ARE BOTH NOW HINTING AT THIS. ONLY WENT WITH SLIGHT
CHANCE POPS FOR NOW. LIMITED INSTABILITY SHOULD PRECLUDE SEVERE
WEATHER.
PER MEDIUM RANGE CONSENSUS...A GENERAL WARMING TREND IS ANTICIPATED
FOR THE WEEKEND AND BEYOND. ADDITIONALLY...HIT-AND-MISS CHANCES FOR
ISOLATED THUNDERSTORMS WILL BE POSSIBLE FROM THE WEEKEND AND BEYOND
GIVEN VARIOUS MODEL PROGS OF SUBTLE MID-UPPER ENERGY AND
MOIST/UNSTABLE CONDITIONS. HOWEVER...CONFIDENCE REMAINS VERY LOW
REGARDING DETAILS OF TIMING/COVERAGE. ALL-IN-ALL IT APPEARS THE
THREAT FOR WIDESPREAD SEVERE WEATHER IS LOW.
KLEINSASSER
AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN HAZARD: THUNDERSTORM POTENTIAL.
WILL KEEP A MENTION OF TS AT HUT...ICT...AND CNU FOR A FEW HOURS
OVERNIGHT GIVEN CURRENT SCATTERED TS ACROSS AREA. ACTIVITY SEEMS
TO BE OCCURRING IN WEAK ISENTROPIC ASCENT NEAR AND NORTH OF WARM
FRONT. HRRR HAS THIS CONVECTION PUSHING EAST OUT OF AREA AROUND
09-10Z. MODEL SIGNALS REMAIN FAIRLY CONSISTENT SHOWING AN MCS
DEVELOPING WEDNESDAY MORNING TO OUR NORTHWEST OVER NEBRASKA AND
NORTHWEST KS...THEN MOVING SOUTHEASTWARD ACROSS CENTRAL/SOUTHEAST
KS INTO WED PM. THERE MAY BE A SEVERAL HOUR BREAK BEHIND THIS MCS.
THEN ADDITIONAL THUNDERSTORMS APPEAR POSSIBLE WEDNESDAY NIGHT WITH
THE COLD FRONT AND MAIN UPPER TROUGH COMING OUT INTO THE PLAINS.
JMC
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 59 71 49 / 50 70 10 10
HUTCHINSON 82 56 70 48 / 50 70 10 10
NEWTON 81 56 69 48 / 50 70 10 10
ELDORADO 82 58 70 48 / 50 70 10 10
WINFIELD-KWLD 84 61 72 50 / 50 70 10 10
RUSSELL 80 52 69 47 / 50 70 10 10
GREAT BEND 81 53 70 47 / 50 70 10 10
SALINA 80 55 69 47 / 50 70 10 10
MCPHERSON 81 55 69 47 / 50 70 10 10
COFFEYVILLE 84 64 72 50 / 40 70 30 10
CHANUTE 83 61 70 48 / 40 70 30 10
IOLA 82 61 70 48 / 40 70 30 10
PARSONS-KPPF 84 63 71 50 / 40 70 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
648 AM CDT WED MAY 30 2012
...UPDATED FOR AVIATION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 330 AM CDT WED MAY 30 2012
FOR THE NEAR TERM, BASED ON THE THE NAM, RUC AND HRRR SHORTER TERM MODELS,
I LOWERED POPS CONSIDERABLY PRIOR TO 18Z TODAY, AND LOWERED QPF AS
WELL. THERE IS A SHORT WAVE EVIDENT IN THE 00Z UPPER AIR ANALYSIS
AND LESS EVIDENT IN THE WATER VAPOR LOOP, AND THIS WAVE WILL COME
DOWN INTO OUR FORECAST AREA LATE TODAY. WITH THAT SAID, THERE
APPEARS ONLY TO BE SLIGHT OVER RUNNING CONDITIONS THIS MORNING AND
JUST SLIGHT UPSLOPE FLOW. SO CLOUDS MAY INCREASE THIS MORNING IN
THE STRATOCU LEVEL, BUT THE INSTABILITY DOES NOT SEEM STRONG
ENOUGH FOR ANY CONVECTION. THE FRONT DOWN IN OKLAHOMA WILL NUDGE
NORTH BY THIS AFTERNOON, AND THE OVER RUNNING OF THE 850MB FLOW
FROM THE SOUTH WILL COLLIDE WITH THE AFOREMENTIONED SHORT WAVE
TRAVELING SOUTHEASTWARD. THESE CONDITIONS WILL SET UP A 1500-1600
CAPE SITUATION ACROSS OUR EASTERN CWA, AND THE SURFACE HEATING BY
THEN WILL LEAD TO MORE INSTABILITY. HAVE KEPT THE LIKELY 60
PERCENT POPS GOING AFTER 21Z IN OUR SOUTHEAST AND EASTERN ZONES,
SOUTHEAST OF A LINE FROM LARNED TO MEADE. IN THE ZONE WORDING, I
WILL HAVE POSSIBLE SEVERE WORDING WITH THE MENTION OF LARGE HAIL
AND DAMAGING WINDS. QPF IS TRICKY, BUT FORECAST SOUNDINGS IN OUR
SOUTHEAST ZONES WOULD PLACE UP TO 1.22 PW IN THE GREENSBURG TO
MEDICINE LODGE AREAS. DO NOT EXPECT THAT AMOUNT IN A BASIN-WIDE
AVERAGE, SO WENT WITH 0.41 INCH INSTEAD. BUMPED HIGH TEMPERATURES
UP JUST A FEW DEGREES TODAY, THINKING THE DELAYED PRECIPITATION
WILL GIVE THE LIMITED SUN MORE TIME TO WARM THE SURFACE UP.
TONIGHT, THERE WILL BE A CHANCE FOR GENERAL STORMS TO OCCUR IN THE
WRAP AROUND SECTION OF THE UPPER WAVE. DO NOT EXPECT TONIGHT`S
STORMS TO BE SEVERE, BUT MORE OF A GENERAL THUNDERSTORM NATURE.
ONLY LIGHT QPF AMOUNTS ARE EXPECTED AFTER MIDNIGHT, WHEN POPS WILL
DIMINISH TO 20 TO 30 PERCENT. MINIMUM TEMPERATURES WILL BE IN THE
UPPER 40S FROM SYRACUSE TO SCOTT CITY, BUT RANGE TO THE UPPER 50S
DOWN IN THE MEDICINE LODGE AREA. WINDS SHOULD BE FROM THE
NORTHEAST AT 10 TO 20 MPH EARLY TONIGHT, THEN SHIFT MORE NORTHERLY
AT 10 TO 15 MPH AFTER MIDNIGHT TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 AM CDT WED MAY 30 2012
BY FRIDAY, THE CLOSED MID LEVEL CIRCULATION WILL BE CENTERED OVER
THE UPPER MISSISSIPPI VALLEY WITH A VERY BROAD NORTHWESTERLY
ORIENTED UPPER JET EXTENDING FROM THE PACIFIC NORTHWEST, THROUGH THE
NORTHERN AND CENTRAL HIGH PLAINS REGIONS. THE SURFACE PATTERN WILL
FEATURE ABOUT A 1015-1017 MB SURFACE HIGH THAT WILL DROP FROM THE
DAKOTAS ON THURSDAY INTO THE CENTRAL PLAINS ON THURSDAY NIGHT. THIS
REPRESENTS A SOMEWHAT COOL NORTHEASTERLY SURFACE FLOW PATTERN FOR
SOUTHWEST KANSAS. THE GFS DOES PAINT LIGHT QPF WHICH REALLY JUST
REPRESENTS THE MODEL ATTEMPTING TO TURN OVER INSTABILITY, IN THE
WESTERN POSITIONS OF THE AREA THURSDAY EVENING. HOWEVER, IT SEEMS
MORE PROBABLE NO THUNDERSTORMS MIGHT BE EXPECTED, ESPECIALLY GIVEN
THAT THE SUBSIDENT THERMALLY INDIRECT CONVERGENT RIGHT FRONT
QUADRANT OF THE INCOMING JET SHOULD BE FOCUSED OVER WESTERN KANSAS.
FROM THURSDAY NIGHT INTO FRIDAY, THE SURFACE HIGH PRESSURE SLIDES
RAPIDLY INTO THE SOUTHERN PLAINS. AS A RESULT A STOUT SURFACE
PRESSURE GRADIENT DEVELOPS OVER WESTERN KANSAS BY FRIDAY AFTERNOON,
WHICH SHOULD PRODUCE AT LEAST BREEZY SOUTHERLY WINDS. DURING THE
TIMEFRAME FROM FRIDAY MORNING INTO FRIDAY NIGHT, BOTH THE ECMWF AND
GFS PRODUCE A SWATH OF QPF SLIDING SOUTH ACROSS NORTHERN AND CENTRAL
KANSAS. THERE IS CONSIDERABLE DEFORMATION IN THE MID LEVEL HEIGHT
FIELD AND SOME INDICATION OF A WEAK SHORTWAVE MOVING INTO THE AREA.
HOWEVER, BY CONTRAST, THE NAM MODEL SEEMS TO INDICATE CONVECTION
DEVELOPED DIURNALLY ALONG A SURFACE CONVERGENCE AXIS/ MOISTURE
DISCONTINUITY LATE IN THE DAY. ISOLATED STORMS SEEM ALL THAT MIGHT
BE EXPECTED. WITH THESE DIFFERENT SOLUTIONS, THERE IS PLENTY OF
UNCERTAINTY IN THE EXPECTED MESOSCALE DETAILS FOR LATE FRIDAY.
ON SATURDAY, THE UPPER RIDGE BEGINS TO BUILD SLIGHTLY FARTHER EAST.
THEREFORE A SLIGHT INCREASE IN TEMPERATURES CAN BE EXPECTED WITH
INCREASING THICKNESSES. ECMWF/GFS ELUDE TO THE AREA FROM SOUTH
CENTRAL KANSAS INTO OKLAHOMA AS BEING POTENTIALLY CONVECTIVELY
ACTIVE IN A ZONE OF HIGHER THETA-E. LESSER CONFIDENCE EXISTS WITH
RESPECT TO ANY STORM CHANCES BEYOND THIS POINT. THE MODELS BEGIN TO
TAKE ON A FLAT RIDGE PATTERN INTO SUNDAY WITH A NOISY SIGNAL OF
EMBEDDED COMPACT SHORTWAVE ENERGY AROUND THE AREA. GFS ENSEMBLE
TEMPERATURES WARM TO NEAR 90S DEGREES BY SUNDAY AFTERNOON, BUT STILL
INDICATE AROUND A 10 DEGREE SPREAD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 647 AM CDT WED MAY 30 2012
HIGH PRESSURE OVER THE NORTHERN PLAINS IS AIDING LIGHT EASTERLY
SURFACE FLOW ACROSS WESTERN KANSAS THIS MORNING. DESTABILIZATION OF
THE ATMOSPHERE WILL OCCUR AS STRONG INSOLATION BEGINS THROUGH THE
LATE MORNING AND EARLY AFTERNOON. MODELS TEND TO SUPPORT CONVECTIVE
INITIATION AHEAD OF AN ADVANCING COLD FRONT FRONT NEBRASKA, WITH DEEP
MOIST CONVECTION BECOMING MORE WIDESPREAD TO THE SOUTH ACROSS MUCH
OF CENTRAL KANSAS OVER THE MIDDLE TO LATE AFTERNOON HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 54 72 45 / 50 40 0 0
GCK 80 52 72 45 / 40 40 0 0
EHA 84 54 76 48 / 40 40 0 0
LBL 83 53 75 47 / 40 40 0 0
HYS 76 52 69 44 / 40 30 0 10
P28 84 59 72 46 / 60 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
340 AM CDT WED MAY 30 2012
...UPDATED FOR THE SHORT TERM AND LONG TERM DISCUSSION...
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 330 AM CDT WED MAY 30 2012
FOR THE NEAR TERM, BASED ON THE THE NAM, RUC AND HRRR SHORTER TERM MODELS,
I LOWERED POPS CONSIDERABLY PRIOR TO 18Z TODAY, AND LOWERED QPF AS
WELL. THERE IS A SHORT WAVE EVIDENT IN THE 00Z UPPER AIR ANALYSIS
AND LESS EVIDENT IN THE WATER VAPOR LOOP, AND THIS WAVE WILL COME
DOWN INTO OUR FORECAST AREA LATE TODAY. WITH THAT SAID, THERE
APPEARS ONLY TO BE SLIGHT OVER RUNNING CONDITIONS THIS MORNING AND
JUST SLIGHT UPSLOPE FLOW. SO CLOUDS MAY INCREASE THIS MORNING IN
THE STRATOCU LEVEL, BUT THE INSTABILITY DOES NOT SEEM STRONG
ENOUGH FOR ANY CONVECTION. THE FRONT DOWN IN OKLAHOMA WILL NUDGE
NORTH BY THIS AFTERNOON, AND THE OVER RUNNING OF THE 850MB FLOW
FROM THE SOUTH WILL COLLIDE WITH THE AFOREMENTIONED SHORT WAVE
TRAVELING SOUTHEASTWARD. THESE CONDITIONS WILL SET UP A 1500-1600
CAPE SITUATION ACROSS OUR EASTERN CWA, AND THE SURFACE HEATING BY
THEN WILL LEAD TO MORE INSTABILITY. HAVE KEPT THE LIKELY 60
PERCENT POPS GOING AFTER 21Z IN OUR SOUTHEAST AND EASTERN ZONES,
SOUTHEAST OF A LINE FROM LARNED TO MEADE. IN THE ZONE WORDING, I
WILL HAVE POSSIBLE SEVERE WORDING WITH THE MENTION OF LARGE HAIL
AND DAMAGING WINDS. QPF IS TRICKY, BUT FORECAST SOUNDINGS IN OUR
SOUTHEAST ZONES WOULD PLACE UP TO 1.22 PW IN THE GREENSBURG TO
MEDICINE LODGE AREAS. DO NOT EXPECT THAT AMOUNT IN A BASIN-WIDE
AVERAGE, SO WENT WITH 0.41 INCH INSTEAD. BUMPED HIGH TEMPERATURES
UP JUST A FEW DEGREES TODAY, THINKING THE DELAYED PRECIPITATION
WILL GIVE THE LIMITED SUN MORE TIME TO WARM THE SURFACE UP.
TONIGHT, THERE WILL BE A CHANCE FOR GENERAL STORMS TO OCCUR IN THE
WRAP AROUND SECTION OF THE UPPER WAVE. DO NOT EXPECT TONIGHT`S
STORMS TO BE SEVERE, BUT MORE OF A GENERAL THUNDERSTORM NATURE.
ONLY LIGHT QPF AMOUNTS ARE EXPECTED AFTER MIDNIGHT, WHEN POPS WILL
DIMINISH TO 20 TO 30 PERCENT. MINIMUM TEMPERATURES WILL BE IN THE
UPPER 40S FROM SYRACUSE TO SCOTT CITY, BUT RANGE TO THE UPPER 50S
DOWN IN THE MEDICINE LODGE AREA. WINDS SHOULD BE FROM THE
NORTHEAST AT 10 TO 20 MPH EARLY TONIGHT, THEN SHIFT MORE NORTHERLY
AT 10 TO 15 MPH AFTER MIDNIGHT TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 330 AM CDT WED MAY 30 2012
BY FRIDAY, THE CLOSED MID LEVEL CIRCULATION WILL BE CENTERED OVER
THE UPPER MISSISSIPPI VALLEY WITH A VERY BROAD NORTHWESTERLY
ORIENTED UPPER JET EXTENDING FROM THE PACIFIC NORTHWEST, THROUGH THE
NORTHERN AND CENTRAL HIGH PLAINS REGIONS. THE SURFACE PATTERN WILL
FEATURE ABOUT A 1015-1017 MB SURFACE HIGH THAT WILL DROP FROM THE
DAKOTAS ON THURSDAY INTO THE CENTRAL PLAINS ON THURSDAY NIGHT. THIS
REPRESENTS A SOMEWHAT COOL NORTHEASTERLY SURFACE FLOW PATTERN FOR
SOUTHWEST KANSAS. THE GFS DOES PAINT LIGHT QPF WHICH REALLY JUST
REPRESENTS THE MODEL ATTEMPTING TO TURN OVER INSTABILITY, IN THE
WESTERN POSITIONS OF THE AREA THURSDAY EVENING. HOWEVER, IT SEEMS
MORE PROBABLE NO THUNDERSTORMS MIGHT BE EXPECTED, ESPECIALLY GIVEN
THAT THE SUBSIDENT THERMALLY INDIRECT CONVERGENT RIGHT FRONT
QUADRANT OF THE INCOMING JET SHOULD BE FOCUSED OVER WESTERN KANSAS.
FROM THURSDAY NIGHT INTO FRIDAY, THE SURFACE HIGH PRESSURE SLIDES
RAPIDLY INTO THE SOUTHERN PLAINS. AS A RESULT A STOUT SURFACE
PRESSURE GRADIENT DEVELOPS OVER WESTERN KANSAS BY FRIDAY AFTERNOON,
WHICH SHOULD PRODUCE AT LEAST BREEZY SOUTHERLY WINDS. DURING THE
TIMEFRAME FROM FRIDAY MORNING INTO FRIDAY NIGHT, BOTH THE ECMWF AND
GFS PRODUCE A SWATH OF QPF SLIDING SOUTH ACROSS NORTHERN AND CENTRAL
KANSAS. THERE IS CONSIDERABLE DEFORMATION IN THE MID LEVEL HEIGHT
FIELD AND SOME INDICATION OF A WEAK SHORTWAVE MOVING INTO THE AREA.
HOWEVER, BY CONTRAST, THE NAM MODEL SEEMS TO INDICATE CONVECTION
DEVELOPED DIURNALLY ALONG A SURFACE CONVERGENCE AXIS/ MOISTURE
DISCONTINUITY LATE IN THE DAY. ISOLATED STORMS SEEM ALL THAT MIGHT
BE EXPECTED. WITH THESE DIFFERENT SOLUTIONS, THERE IS PLENTY OF
UNCERTAINTY IN THE EXPECTED MESOSCALE DETAILS FOR LATE FRIDAY.
ON SATURDAY, THE UPPER RIDGE BEGINS TO BUILD SLIGHTLY FARTHER EAST.
THEREFORE A SLIGHT INCREASE IN TEMPERATURES CAN BE EXPECTED WITH
INCREASING THICKNESSES. ECMWF/GFS ELUDE TO THE AREA FROM SOUTH
CENTRAL KANSAS INTO OKLAHOMA AS BEING POTENTIALLY CONVECTIVELY
ACTIVE IN A ZONE OF HIGHER THETA-E. LESSER CONFIDENCE EXISTS WITH
RESPECT TO ANY STORM CHANCES BEYOND THIS POINT. THE MODELS BEGIN TO
TAKE ON A FLAT RIDGE PATTERN INTO SUNDAY WITH A NOISY SIGNAL OF
EMBEDDED COMPACT SHORTWAVE ENERGY AROUND THE AREA. GFS ENSEMBLE
TEMPERATURES WARM TO NEAR 90S DEGREES BY SUNDAY AFTERNOON, BUT STILL
INDICATE AROUND A 10 DEGREE SPREAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1237 AM CDT WED MAY 30 2012
THE LATEST NAM MODEL RUN FROM 00Z SHOWS MOISTURE WILL BE MOVING
IN BY 09-10Z OR SO AND PRODUCING MVFR CIGS IN THE BKN020-025 RANGE.
WINDS WILL BE NORTHEAST AT 10 TO 20 KTS. BY 15Z, A SHORT WAVE WILL
MOVE SOUTHEAST FROM NORTHWESTERN COLORADO AND KICK OFF SCATTERED
THUNDERSTORMS. THE BEST TIMING ESTIMATE FOR CONVECTION AT THE
TAFS WILL BE 15Z AT KHYS, 16Z AT KDDC, AND WILL ONLY GO VCTS AT
KGCK AS THE MOIST AXIS WILL STAY TO THE EAST OF KGCK. THIS WAVE
WILL BE FAST MOVING, AND THUNDERSTORM COULD BE EAST OF ALL
TERMINALS BY 19Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 54 72 45 / 50 40 0 0
GCK 80 52 72 45 / 40 40 0 0
EHA 84 54 76 48 / 40 40 0 0
LBL 83 53 75 47 / 40 40 0 0
HYS 76 52 69 44 / 40 30 0 10
P28 84 59 72 46 / 60 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...RUSSELL
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS WICHITA KS
330 AM CDT WED MAY 30 2012
.DISCUSSION...
FORECAST HIGHLIGHTS INCLUDE THUNDERSTORM CHANCES TODAY &
TONIGHT...MUCH COOLER TEMPERATURES FOR THU-FRI...AND A WARMING TREND
WEEKEND AND BEYOND.
LOW CONFIDENCE IN OPERATIONAL MODELS FOR TODAY-TONIGHT...AS THEY
HAVE GREATLY STRUGGLED WITH PLACEMENT AND MAGNITUDE OF
MOISTURE/INSTABILITY PROGS THE PAST FEW DAYS. AM TENDING TO SIDE
WITH A 06Z NAM...RUC...HRRR AND NSSL WRF BLEND...WHICH HOLDS OFF
MOST PRECIPITATION UNTIL AFTERNOON. THIS MAKES THE MOST SENSE GIVEN
BRUNT OF INSTABILITY HAS BEEN SHUNTED SOUTH DUE TO WIDESPREAD
OVERNIGHT CONVECTION SCOURING OUT AIRMASS OVER OK. HOWEVER...DID
HOLD ONTO SOME LOW POPS THIS MORNING TO ACCOUNT FOR POSSIBLE
HIT-AND-MISS ISOLATED THUNDERSTORM ACTIVITY FORMING ALONG STALLED
850-700MB BAROCLINIC ZONE ORIENTED NW-SE ACROSS KS.
BY THIS AFTERNOON...THINKING STORM COVERAGE SHOULD GRADUALLY
INCREASE OVER THE HIGH PLAINS...AS AN ELONGATED MID/UPPER TROUGH
CURRENTLY OVER THE ROCKIES APPROACHES FROM THE WEST...INTERACTING
WITH AN INCREASINGLY MOIST/UNSTABLE LOW-LEVEL AIRMASS. THIS ACTIVITY
SHOULD THEN DIVE SOUTHEAST ACROSS THE AREA THROUGH THE
AFTERNOON/EVENING ALONG NORTHERN FRINGE OF STOUT 700MB TEMPERATURES.
THINKING SEVERE THUNDERSTORMS CAPABLE OF HAIL/WIND WILL BE POSSIBLE
GIVEN INCREASINGLY MODEST/STRONG INSTABILITY (POSSIBLY MAINLY
ELEVATED) AND DECENT DEEP LAYER SHEAR. HOWEVER...THINK THE "HIGHER
END" SEVERE WEATHER WILL BE CONFINED TO TX/OK WHERE BEST SFC-BASED
INSTABILITY WILL BE CO-LOCATED WITH OLD OUTFLOW BOUNDARY/DRYLINE
INTERSECTIONS. THEREFORE...WILL REMOVE "CATEGORY 4" FROM HAZARDOUS
WEATHER OUTLOOK. AFTER THIS INITIAL ROUND OF STORMS...ANOTHER ROUND
OF SHOWERS/THUNDERSTORMS SHOULD ROLL SOUTHEAST ACROSS THE REGION
LATER TONIGHT ASSOCIATED WITH THE PARENT STRONG SHORTWAVE AND
ASSOCIATED STRONG COLD FRONT. THE SEVERITY OF THIS ACTIVITY MAY BE
TEMPERED THOUGH DUE TO PREVIOUS ACTIVITY ACTING TO STABILIZE THE
AIRMASS ACROSS THE AREA.
MUCH COOLER WEATHER ANTICIPATED FOR THU-FRI IN WAKE OF THE COLD
FRONT...ALONG WITH STOUT NORTH WINDS THU. FOR FRIDAY...SUBTLE
MID/UPPER ENERGY DIVING SOUTHEAST IN FAST NORTHWEST FLOW ALOFT MAY
RESULT IN ISOLATED/WIDELY SCATTERED ELEVATED
SHOWERS/THUNDERSTORMS...AS 850-700MB WARM/MOIST ADVECTION INCREASES.
GFS AND ECMWF ARE BOTH NOW HINTING AT THIS. ONLY WENT WITH SLIGHT
CHANCE POPS FOR NOW. LIMITED INSTABILITY SHOULD PRECLUDE SEVERE
WEATHER.
PER MEDIUM RANGE CONSENSUS...A GENERAL WARMING TREND IS ANTICIPATED
FOR THE WEEKEND AND BEYOND. ADDITIONALLY...HIT-AND-MISS CHANCES FOR
ISOLATED THUNDERSTORMS WILL BE POSSIBLE FROM THE WEEKEND AND BEYOND
GIVEN VARIOUS MODEL PROGS OF SUBTLE MID-UPPER ENERGY AND
MOIST/UNSTABLE CONDITIONS. HOWEVER...CONFIDENCE REMAINS VERY LOW
REGARDING DETAILS OF TIMING/COVERAGE. ALL-IN-ALL IT APPEARS THE
THREAT FOR WIDESPREAD SEVERE WEATHER IS LOW.
KLEINSASSER
&&
.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN HAZARD: THUNDERSTORM POTENTIAL.
WILL KEEP A MENTION OF TS AT HUT...ICT...AND CNU FOR A FEW HOURS
OVERNIGHT GIVEN CURRENT SCATTERED TS ACROSS AREA. ACTIVITY SEEMS
TO BE OCCURRING IN WEAK ISENTROPIC ASCENT NEAR AND NORTH OF WARM
FRONT. HRRR HAS THIS CONVECTION PUSHING EAST OUT OF AREA AROUND
09-10Z. MODEL SIGNALS REMAIN FAIRLY CONSISTENT SHOWING AN MCS
DEVELOPING WEDNESDAY MORNING TO OUR NORTHWEST OVER NEBRASKA AND
NORTHWEST KS...THEN MOVING SOUTHEASTWARD ACROSS CENTRAL/SOUTHEAST
KS INTO WED PM. THERE MAY BE A SEVERAL HOUR BREAK BEHIND THIS MCS.
THEN ADDITIONAL THUNDERSTORMS APPEAR POSSIBLE WEDNESDAY NIGHT WITH
THE COLD FRONT AND MAIN UPPER TROUGH COMING OUT INTO THE PLAINS.
JMC
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 81 59 71 49 / 60 70 10 10
HUTCHINSON 79 56 70 48 / 60 70 10 10
NEWTON 78 56 69 48 / 60 70 10 10
ELDORADO 80 58 70 48 / 50 70 10 10
WINFIELD-KWLD 83 61 72 50 / 60 70 10 10
RUSSELL 76 52 69 47 / 60 70 10 10
GREAT BEND 77 53 70 47 / 60 70 10 10
SALINA 77 55 69 47 / 60 70 10 10
MCPHERSON 78 55 69 47 / 60 70 10 10
COFFEYVILLE 84 64 72 50 / 40 70 30 10
CHANUTE 81 61 70 48 / 40 70 30 10
IOLA 80 61 70 48 / 40 70 30 10
PARSONS-KPPF 82 63 71 50 / 40 70 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1202 AM MDT WED MAY 30 2012
.UPDATE...
ISSUED AT 1155 PM MDT TUE MAY 29 2012
FOR THE REST OF TONIGHT...ELEVATED THUNDERSTORM CHANCES CONTINUE
TO BE THE PRIMARY CONCERNS FOR THE OVERNIGHT HOURS AS ELEVATED
INSTABILITY WILL INCREASE BTWN 06 AND 12Z AS 305K SFC INDICATES
MIXING RATIOS CLIMBING SHARPLY AS FLOW ALOFT BECOMES
SOUTHEASTERLY. NEWEST MODELS STILL SHOW A LARGE DEGREE OF
UNCERTAINTY WITH RESPECT TO OVERNIGHT/EARLY MORNING CONVECTION
THAT LIMITS CONFIDENCE SOMEWHAT...AND ADJUSTED POPS TO PEAK AROUND
15Z INSTEAD OF 12Z AS PREVIOUSLY EXPECTED. VWP AT DDC INDICATING WINDS
SLOWLY STARTING TO VEER TO THE EAST AROUND 40 KTS...AND GIVEN SFC
TDS TO THE EAST THERE IS AT LEAST A LITTLE SUPPORT FOR STRONG
MOISTURE ADVECTION TO OCCUR OVERNIGHT.
TODAY...BULK OF FORECAST CONCERNS CENTER AROUND WHETHER OR NOT
THUNDERSTORMS WILL BE ONGOING IN THE MORNING AND THE RESULTING
IMPACTS ON BOTH TEMPS AND LATER THUNDERSTORM DEVELOPMENT. DIV Q
FIELDS SUGGEST LARGE SCALE FORCING FOR ASCENT WELL AHEAD OF
APPROACHING SHORT WAVE TROUGH AND WITH PERSISTENT LIFT IN AREA OF
FAIRLY STRONG MOISTURE ADVECTION...THINK KEEPING MORNING POPS AT
LEAST IN THE MID CHANCE RANGE WARRANTED. SEEING HRRR/RAP AND
LATEST HIGHRES NAM ARW SOLUTIONS KEEPS CONFIDENCE TOO LOW TO GO
MUCH HIGHER THAN THAT. BY LATE AFTERNOON SHORT WAVE TROUGH WILL
BEGIN TO MOVE INTO NORTHERN NEBRASKA...FORCING COLD FRONT INTO
NORTHWESTERN CWA. WITH MORNING PRECIPITATION THREAT ENDING EARLY
IN THE WEST...THINK SUFFICIENT HEATING DESTABILIZATION WILL OCCUR TO
ALLOW FOR THUNDERSTORM REDEVELOPMENT AS FRONT BEGINS TO SWEEP
ACROSS THE AREA. GIVEN WEAK CINH AND STRONG SFC FORCING ALONG
FRONT...THINK BEST CHANCE FOR PRECIPITATION WILL BE DURING THIS
TIME AND HAVE TRENDED FORECAST IN THAT DIRECTION.
UPDATE ISSUED AT 904 PM MDT TUE MAY 29 2012
MAIN CONCERN FOR THE OVERNIGHT PERIOD WILL BE POTENTIAL FOR
ELEVATED THUNDERSTORM DEVELOPMENT EARLY THIS MORNING. LATEST NAM
AND RUC INDICATE ISENTROPIC UPGLIDE INCREASING BTWN 9 AND 12Z
ALONG 305K SFC WITH ELEVATED MOISTURE TRANSPORT INCREASING THROUGH
THE NIGHT WITH MIXING RATIOS AROUND 12 G/KG REACHING AREA BY 12Z.
NAM/RUC/21Z SREF PLUME DIAGRAMS SHOWING MUCAPES INCREASING
DRAMATICALLY OVERNIGHT...WITH VALUES IN EXCESS OF 2000 J/KG NOTED
ON NAM AND SREF MEAN VALUES INCREASING 1500 J/KG. SOUNDINGS
SUGGEST THIS INSTABILITY BASED IN AREA OF ISENTROPIC ASCENT WITH
CINH VALUES DECREASING THROUGH THE NIGHT WITH A LARGE AREA OF CWA
SEEING ELEVATED CINHS FALL BELOW 50 J/KG AFTER 09Z. MODELS DIFFER
GREATLY ON INITIATION POTENTIAL WITH THE LATEST NAM STARTING TO
INITIATE EARLIER THAN PREVIOUS RUNS ALTHOUGH OVERALL PATTERNS VERY
SIMILAR. THINK DECIDING FACTOR TONIGHT WILL BE HOW QUICKLY
MOISTURE ADVECTION BEGINS. WITH NEAR SATURATED CONDITIONS ELEVATED
CINH VERY WEAK AT H8...BUT IF THINGS ADVECT IN SLOWER CINH WILL BE
MUCH STRONGER TONIGHT.
GIVEN OVERALL PATTERN AND AVAILABLE DATA...THINK INCREASING POPS
IN THE EARLY MORNING HOURS WARRANTED DESPITE MODEL DIFFERENCES.
WITH ELEVATED CAPES AROUND 1500 J/KG (POSSIBLY IN EXCESS OF 2500
J/KG) THINK THERE IS A DECENT THREAT FOR LARGE HAIL TONIGHT SHOULD
STORMS DEVELOP.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 201 PM MDT TUE MAY 29 2012
THROUGH TONIGHT...PRIMARY FORECAST CHANGE OVERNIGHT WAS TO ADD SLIGHT
CHANCE/CHANCE POPS ACROSS THE NORTHEASTERN PORTION OF THE FORECAST
AREA. STRONG ISENTROPIC UPGLIDE AND INCREASING FORCING FOR ASCENT
ON THE NOSE OF A 40-45 KT H85 LOW LEVEL JET WILL RESULT IN THE
DEVELOPMENT OF CONVECTION ACROSS THE CHEYENNE RIDGE. DURING THE
OVERNIGHT HOURS...THIS CONVECTION SHOULD PROPAGATE SOUTHEASTWARD
TOWARD THE FORECAST AREA. SOME QUESTION WITH REGARD TO THE SOUTHWESTWARD
EXTENT DOES EXIST.
WEDNESDAY AND WEDNESDAY NIGHT...CONVECTION WILL LIKELY BE ONGOING
OVER THE EASTERN PORTIONS OF THE FORECAST AREA. WILL LIKELY SEE SOME
BREAKS IN THE PRECIP DURING THE LATE MORNING/EARLY AFTERNOON BEFORE
A STRONGER SHORTWAVE TROUGH BEGINS TO IMPACT THE REGION. STRONG TO
SEVERE CONVECTION APPEARS POSSIBLE OVER MUCH OF THE FORECAST AREA.
GUIDANCE DOES DEPICT DISAGREEMENT WITH REGARD TO THE LOCATION OF THE
GREATEST POTENTIAL. THE NAM WOULD SUPPORT CONVECTION INITIALLY ALONG
AND WEST OF THE KS/CO BORDER WHILE THE GFS/EC CONFINE THE THREAT TO
NORTHWEST KANSAS AND SOUTHWEST NEBRASKA. MUCAPE VALUES WILL BE ON
THE ORDER OF 1500-2500 J/KG WHILE DEEP LAYER SHEAR WILL BE SOMEWHAT
MARGINAL UNTIL AFTER 00Z WHEN 0-6KM BULK SHEAR INCREASES TO AROUND
50KTS. ANTICIPATE LARGE HAIL AND STRONG WINDS WILL BE THE PRIMARY
THREATS THOUGH AN ISOLATED TORNADO CANNOT BE RULED OUT DURING THE
LATE AFTERNOON AND EVENING HOURS. A SURFACE COLD FRONT WILL PUSH THROUGH
THE REGION WEDNESDAY NIGHT. LATEST GUIDANCE CONTINUES TO TREND SLOWER
WITH THIS FEATURE SO WILL KEEP PRECIP CHANCES GOING A BIT LONGER
THAN PREVIOUSLY FORECASTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 201 PM MDT TUE MAY 29 2012
500 MB LOW OVER EASTERN NEBRASKA/WESTERN IOWA WILL MOVE EAST THURSDAY
LEAVING THE FORECAST AREA IN COOLER/DRY NORTHWEST FLOW ALOFT. GFS/NAM
INDICATE SOME LINGERING SHOWERS EARLY THURSDAY MORNING...BUT WILL LEAN
TOWARDS THE DRIER ECMWF. TEMPERATURE GUIDANCE THURSDAY SHOWS WIDE
VARIATION BETWEEN MODELS. COLD AIR ADVECTION WILL BE EASING...BUT
THERE SHOULD BE ENOUGH COOL AIR ALREADY IN PLACE TO KEEP MAXIMUM
TEMPERATURES IN THE UPPER 60S TO THE LOWER 70S.
LEE SIDE TROUGH IS PROGGED TO DEVELOP FRIDAY AFTERNOON WHICH WILL
PRODUCE SOUTH WINDS/WARM AIR ADVECTION. LOW LEVEL JET MAY DEVELOP
FRIDAY NIGHT...BUT BEST MOISTURE WILL BE EAST OF THE AREA...SO WILL
KEEP FORECAST DRY.
A NUMBER OF WEAK MID LEVEL WAVES WILL MOVE ACROSS THE AREA SATURDAY
THROUGH TUESDAY. MOST MODELS INDICATE CONVECTION SATURDAY NIGHT
WITH ONE OF THE WAVES...THOUGH MODELS DIFFER IN THE EXTENT OF THE
COVERAGE. WILL PLACE LOW CHANCE POPS IN THE SOUTHWESTERN PART OF
FORECAST AREA PRIMARILY BASED ON GFS LOCATION.
ZONAL FLOW OCCURS SUNDAY...AND HAVE KEPT THE FORECAST DRY. ANOTHER
SHORT WAVE MOVES THROUGH THE AREA MONDAY...AND INDICATED SOME SMALL
CHANCE POPS AGAIN...THOUGH CONFIDENCE IS NOT PARTICULARLY HIGH. MORE
VIGOROUS DYNAMICS ARRIVE MONDAY NIGHT/TUESDAY IN ADVANCE OF DEVELOPING
WESTERN UNITED STATES TROUGH.
NUMERICAL TEMPERATURE GUIDANCE LOOKS REASONABLE THROUGH THE EXTENDED
PERIOD AND ONLY MADE SLIGHT ADJUSTMENTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1140 PM MDT TUE MAY 29 2012
THUNDERSTORM CHANCES AND ASSOCIATED CIG/VISBY IMPACTS WILL BE
PRIMARY CONCERN FOR BOTH TERMINALS FOR THE NEXT 24 HOURS. LOOKS
LIKE EACH SITE WILL HAVE TWO DISTINCT PERIODS WHERE THUNDERSTORMS
ARE POSSIBLE...THE FIRST WILL BE THIS MORNING IN AREA WARM AIR
ADVECTION ALONG LOW LEVEL JET...AND THE SECOND BEING IN THE LATE
AFTERNOON AND EARLY EVENING AS COLD FRONT SWEEPS ACROSS AREA.
LATEST DATA WOULD SUGGEST THE FRONTAL PASSAGE WILL HAVE BEST
COVERAGE AND THUS HIGHER CHANCES OF IMPACTING TERMINALS. WITH
ELEVATED MOISTURE ADVECTION EXPECTED TO INCREASE AFTER 06Z...WILL
SEE A FEW PERIODS OF MVFR CIGS WITH STRATUS DEVELOP MAINLY THIS MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JRM
SHORT TERM...FOLTZ
LONG TERM...MENTZER
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS WICHITA KS
1137 PM CDT TUE MAY 29 2012
.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN HAZARD: THUNDERSTORM POTENTIAL.
WILL KEEP A MENTION OF TS AT HUT...ICT...AND CNU FOR A FEW HOURS
OVERNIGHT GIVEN CURRENT SCATTERED TS ACROSS AREA. ACTIVITY SEEMS
TO BE OCCURRING IN WEAK ISENTROPIC ASCENT NEAR AND NORTH OF WARM
FRONT. HRRR HAS THIS CONVECTION PUSHING EAST OUT OF AREA AROUND
09-10Z. MODEL SIGNALS REMAIN FAIRLY CONSISTENT SHOWING AN MCS
DEVELOPING WEDNESDAY MORNING TO OUR NORTHWEST OVER NEBRASKA AND
NORTHWEST KS...THEN MOVING SOUTHEASTWARD ACROSS CENTRAL/SOUTHEAST
KS INTO WED PM. THERE MAY BE A SEVERAL HOUR BREAK BEHIND THIS MCS.
THEN ADDITIONAL THUNDERSTORMS APPEAR POSSIBLE WEDNESDAY NIGHT WITH
THE COLD FRONT AND MAIN UPPER TROUGH COMING OUT INTO THE PLAINS.
JMC
&&
.PREV DISCUSSION... /ISSUED 940 PM CDT TUE MAY 29 2012/
UPDATE...
WILL MAINTAIN A SLIGHT CHANCE OF THUNDERSTORMS OVERNIGHT FOR MOST
OF THE AREA...WITH HIGHER PROBABILITIES NEAR THE OKLAHOMA BORDER
IN THE FAR SOUTHEAST KS COUNTIES. WEST TO EAST ORIENTED WARM FRONT
WILL REMAIN IN PLACE ACROSS SOUTHERN KS OVERNIGHT WITH STRONG
INSTABILITY ALONG/SOUTH OF IT AND 40 KT OF DEEP LAYER SHEAR.
ALTHOUGH AN ISOLATED STRONG TO MARGINALLY SEVERE STORM REMAINS
POSSIBLE IN THE SOUTH...THE SIGNIFICANT SEVERE THREAT SHOULD
REMAIN TO OUR SOUTH WITH THE DEVELOPING MCS IN OKLAHOMA. OTHER
STRONG TO SEVERE STORMS MAY ERUPT OVER NORTHWESTERN KS TOWARD DAYBREAK
IN AREA OF INCREASED MOISTURE TRANSPORT AHEAD OF A WEAKER LEAD WAVE
IN THE ROCKIES THAT PRECEDES THE STRONG SHORTWAVE OVER THE
NORTHERN ROCKIES. FEEL THIS INITIAL WEAKER WAVE WILL RESULT IN AN
MCS THAT MOVES SOUTHEAST ACROSS OUR AREA DURING THE DAY...WITH
PERHAPS ANOTHER MCS COMING WEDNESDAY NIGHT WITH THE MAIN SYSTEM.
JMC
PREV DISCUSSION... /ISSUED 620 PM CDT TUE MAY 29 2012/
AVIATION...00Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
MAIN HAZARD: STRONG THUNDERSTORMS TONIGHT-WEDNESDAY.
WILL KEEP A VCTS MENTION THIS EVENING ROUGHLY ALONG/SOUTH OF
HIGHWAY 54 AFFECTING ICT AND CNU TAFS. STRONG OUTFLOW WINDS AND
HAIL WILL BE POSSIBLE NEAR ANY STORMS THIS EVENING. ALTHOUGH
HIGHER PROBABILITIES WILL EXIST IN OKLAHOMA...A FEW STRONG STORMS
COULD DEVELOP IN SOUTH CENTRAL/SOUTHEAST KS THIS EVE AS WEAK
IMPULSE TRACKS EASTWARD OUT OF THE 4 CORNERS REGION. ANOTHER
DISTURBANCE WILL TRACK SOUTHEASTWARD OUT OF THE ROCKIES
WEDNESDAY...AND SHORT TERM MODEL DATA SUGGESTS A POTENTIALLY MORE
WIDESPREAD COVERAGE WITH THIS FEATURE ANYTIME FROM LATE MORNING
INTO THE AFTERNOON/EVENING. WILL INCLUDE VCTS MENTION AT THIS TIME
AND PROVIDE BETTER TIMING DETAILS IN LATER TAFS.
JMC
PREV DISCUSSION... /ISSUED 337 PM CDT TUE MAY 29 2012/
DISCUSSION...
MAIN FORECAST CONCERNS WILL BE CHANCE FOR SEVERE STORMS THIS EVENING
AND AGAIN ON WED. THEN COOLER/DRIER AIR FOR THU AND FRI.
TONIGHT:
CURRENT SFC ANALYSIS SHOWS LOW LEVEL MOISTURE PROFILES JUST TO THE
SW OF THE FORECAST AREA IN NW OK BECOMING VERY UNSTABLE...WITH
VISIBLE SATELLITE SHOWING CU FIELD INCREASING JUST TO OUR SOUTH AND
WEST. LOW LEVEL MOISTURE RETURN AND UNSTABLE AIRMASS HAS BEEN SLOW
TO RETURN TO SOUTH CENTRAL KS AT THIS TIME...WITH WARM FRONTAL
BOUNDARY CURRENTLY LOCATED ALONG THE SRN ROW OF COUNTIES IN SOUTH
CEN KS. WILL HAVE TO KEEP ANY EYE ON THIS SRN ROW OF COUNTIES...AS
THIS AREA IS BECOMING UNCAPPED...SO ANY INCREASE IN SFC MOISTURE MAY
LEAD TO SUPERCELL STORMS DEVELOPING SW OF KICT. IF A STORM CAN
DEVELOP INTO SOUTH CEN KS...BULK SHEAR OF 50 KTS AND MLCAPE REACHING
1500-2000 J/KG...ANY STORM THAT DEVELOPS HAS THE POTENTIAL TO BECOME
SEVERE WITH LARGE HAIL AND DAMAGING WINDS. ALSO A SMALL WINDOW OF
OPPORTUNITY FOR A TORNADO WITH A DOMINATE SUPERCELL...AS DIRECTIONAL
SHEAR LOOKS FAVORABLE FOR A TORNADO CHANCE INITIALLY...BEFORE STORMS
EVOLVE INTO A PROGRESSIVE MESOSCALE CONVECTIVE SYSTEM (MCS) MOVING
SOUTH-SOUTHEAST INTO OK.
WED-WED NIGHT:
A MORE COMPLICATED SEVERE WEATHER SETUP WILL OCCUR ON WED...AS THE
WARM FRONTAL BOUNDARY SHIFTS A LITTLE FURTHER NORTH OVER CEN KS...
WITH WARM ADVECTION OVERRUNNING THIS BOUNDARY ONGOING EARLY ON WED.
THIS WILL PROBABLY LEAD TO ELEVATED CONVECTION DURING THE VERY EARLY
MORNING HOURS ON WED JUST TO THE NW OF CEN KS AS A MORE VIGOROUS
SHORTWAVE APPROACHES NW KS.
SOME UNCERTAINTY ON HOW THIS MORNING CONVECTION WILL IMPACT SEVERE
CHANCES FOR WED AFTN...AS THIS CONVECTION MAY PROPAGATE SE INTO
SOUTH CENTRAL KS AND BECOME MORE SFC BASED FOR THE EARLY AFTERNOON
HOURS...AS THE CONVECTION RUNS INTO BETTER SFC BASED INSTABILITY.
EXPECTING MORE ROBUST BULK SHEAR VALUES ON WED AFTN...AS THIS
SHORTWAVE MOVES EAST-SOUTHEAST WITH THE NAM/WRF SHOWING BULK SHEAR
VALUES INCREASING TO 60-65 KTS. THIS ALONG WITH AN UNSTABLE AIRMASS
AGAIN SITUATED ALONG AND SOUTH OF A KHUT-KICT-KPPF LINE. WITH THIS
UNSTABLE AIRMASS AND INCREASING SHEAR...SPC MODERATE RISK LOOKS
REASONABLE FOR WED AFTN. A LITTLE CONCERNED THAT MODERATE RISK MAY
NEED TO BE ADJUSTED A LITTLE FURTHER NORTHEAST.
INITIAL SFC BASED CONVECTION ON WED AFTN CERTAINLY LOOKS LIKE HP
SUPERCELLS GIVEN AMOUNT OF MOISTURE AND SHEAR PROFILES...BUT COULD
SEE THIS CONVECTION CONGEAL OR BECOME OUTFLOW DOMINATE BY LATE
AFTERNOON/EVENING...WHICH COULD LEAD THIS CONVECTION BECOMING A
PROGRESSIVE DAMAGING WIND MCS ACROSS SRN KS BY LATE WED
AFTERNOON/EVENING...AS IT PROGRESSES SOUTH-SOUTHEAST.
THU-SAT:
WILL SEE MOST OF THE WED NIGHT CONVECTION PUSH SOUTH INTO OK EARLY
ON THU. BUT MAIN SHORTWAVE OVER NEB IS EXPECTED TO DROP SOUTHEAST
ACROSS ERN KS FOR THU AFTERNOON. LINGERING LOW LEVEL MOISTURE AND
STEEP LAPSE RATES COULD LEAD A FEW DIURNAL STORMS ACROSS ERN KS FOR
THU...SO WILL KEEP POPS IN THIS AREA. THE MAIN CHANGE FOR THU WILL
BE COOLER/DRIER AIR EXPECTED TO FILTER IN FOR THU AFTN/EVENING.
THIS WILL LEAD TO TEMPS ALMOST 10 DEGREES BELOW NORMAL FOR THU INTO
FRI.
WILL SEE A GRADUAL WARMING TREND ON SAT...AS SFC FLOW QUICKLY COMES
BACK AROUND TO THE SOUTHWEST AS UPPER FLOW STAYS OUT OF THE NW.
THIS RETURN FLOW COULD LEAD TO A CHANCE OF SOME WARM
ADVECTION/ELEVATED CONVECTION LATE FRI NIGHT INTO EARLY ON SAT. SO
WILL ADD A POP FOR THIS CHANCE.
REST OF THE EXTENDED:
MEDIUM RANGE MODELS SUGGEST THE WARMING TREND WILL CONTINUE FOR THE
REST OF THE WEEKEND INTO THE BEGINNING OF NEXT WEEK...AS THE UPPER
FLOW BECOMES MORE ZONAL. THIS WILL LEAD TO SFC TEMPS AGAIN CLIMBING
INTO THE LOW 90S FOR MOST OF CENTRAL AND SOUTH CENTRAL KS FOR SUN
THRU TUE.
WILL ALSO GRADUALLY INCREASE POPS FOR SUN THRU TUE...AS BOTH THE GFS
AND ECMWF SHOW A WEAK FRONTAL BOUNDARY BEGINNING TO SLOWLY SINK
ACROSS THE REGION FOR THIS TIME FRAME.
KETCHAM
AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
LIGHT NORTHEAST WINDS ARE EXPECTED TO BECOME MORE EASTERLY WITH
WIDELY SCATTERED THUNDERSTORMS ANTICIPATED ACROSS SOUTH CENTRAL
AND SOUTHEAST KANSAS AFTER 21Z. SOME OF THE STORMS MAY BECOME
SEVERE BUT DUE TO THE WIDELY SCATTERED NATURE WILL LIMIT KHUT AND
KICT OT VCTS BETWEEN 21Z-02Z. NOCTURNAL THUNDERSTORMS MAY DEVELOP
ACROSS CENTRAL KANSAS LATE IMPACTING KRSL POSSIBLE KHUT AND KICT
TOWARD MORNING ON WED WITH ADDITIONAL CHANCES FOR DEEP MOIST
CONVECTION WEDNESDAY AFTERNOON.
MWM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 62 81 59 72 / 40 60 70 10
HUTCHINSON 59 79 56 71 / 20 60 60 10
NEWTON 58 79 55 70 / 20 50 70 10
ELDORADO 59 79 57 71 / 30 40 70 20
WINFIELD-KWLD 63 83 62 73 / 60 60 70 20
RUSSELL 56 76 53 68 / 20 60 60 10
GREAT BEND 56 77 55 70 / 20 60 60 10
SALINA 57 77 57 68 / 20 40 60 10
MCPHERSON 58 78 55 70 / 20 50 60 10
COFFEYVILLE 63 82 63 74 / 50 30 70 40
CHANUTE 60 79 62 72 / 30 20 70 50
IOLA 59 78 61 70 / 30 20 70 50
PARSONS-KPPF 62 81 63 73 / 50 30 70 50
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1014 PM EDT THU MAY 31 2012
.Forecast Update...
Issued at 1014 PM EDT Thur May 31 2012
The storms this evening have weakened significantly over the last
couple of hours. We have therefore allowed the Severe Thunderstorm
Watch to expire. A few strong thunderstorms remain in south central
Kentucky this evening. Gusty winds and small hail may be seen with
these storms over the next few hours. For the rest of the night, a
second area of showers and thunderstorms has developed back to the
west. The RAP shows at least scattered precip continuing through the
night as the surface low continues to move northeast across the
forecast area. Soundings show instability diminishing overnight as
well. Will therefore hold on to only scattered to isolated thunder
after 06Z. Updates are already out.
.Short Term (Tonight through Friday night)...
Issued at 320 PM EDT Thu May 31 2012
A 500mb trough now over the Upper Midwest will amplify rapidly by
Friday morning as jet stream energy digs south along its back side.
Weak low pressure currently (@ 2pm EDT) over southern Illinois will
slowly move east across southern Indiana and is expected to begin to
deepen pretty rapidly just as it passes north of Louisville late
this evening. An unusually chilly early June airmass will then
arrive early Friday, keeping afternoon highs in the lower to mid
60s, which is not too far from the all time record low high for June
1st (62 at Standiford).
This evening`s precipitation will mostly likely begin as a north
south orientated line of convection that is already beginning to
develop across southern Illinois. Moisture return up to this point
has not been robust as southeast winds have kept dewpoints in the
mid 50s. Winds will eventually veer to the south or southwest by
late afternoon as the aforementioned surface low moves closer to
Louisville.
Despite only weak to moderate instability and moisture return,
strong upper air dynamics coupled with wide surface T/Td depressions
may lead to the formation of one or more bowing segments with a
threat of damaging winds. With backed surface winds, an isolated
tornado east of the developing surface low is possible. However, the
large T/Td depression and relative high Lifted Condensation Level
(LCL) would argue against tornado formation.
Best guess on the timing for this line would have it arriving over
our western counties by late afternoon, crossing Interstate 65 by
early to mid evening, and exiting our Bluegrass Counties around
midnight. With the arrival of this strengthening upper trough,
expect that occasional showers may continue through the early
morning hours.
Even with showers ending during the morning hours, expect somewhat
of a dingy day Friday with persistent low clouds and somewhat brisk
west winds around 10 to 15 mph continue through the afternoon. Skies
will tend to slowly clear beginning from our southwest counties by
late afternoon, with partly cloudy skies arriving over our entire
CWA after midnight. Temperatures will cool well into the 50 to 55
degree range.
.Long Term (Saturday through Wednesday night)...
Issued at 320 PM EDT Thu May 31 2012
Saturday through Sunday night...
The exiting low pressure system to the north and east will place the
forecast area under northwest flow, leaving temperatures cooler than
normal for this time of year. Additionally, this type of flow is
notorious for placing central Kentucky and southern Indiana under
persistent cloud cover and occasional showers. Therefore, have
mentionable PoPs on Saturday afternoon and despite instability
looking weak, given the time of year, included isolated t-storms due
to daytime heating possibly kicking things up a notch. Shower
chances may spread further south Saturday night but looks to clear
out until early next week.
As previously alluded to, temperatures will be below average on
Saturday and Saturday night, with highs in the mid 70s and lows in
the mid 50s. Sunday will see some warm up closer to normal with
highs in the upper 70s and lower 80s and lows in the upper 50s to
low 60s.
Monday through Wednesday night...
This time frame is proving to be a little on the tricky side for the
beginning of the week as the GFS has a surface low pressure system
crossing through the Ohio Valley Monday afternoon into the overnight
period, bringing decent precip chances to the forecast area.
However, the ECMWF is keeping the area dry through the end of the
forecast period. What they do agree on is the stout ridge that
builds over the Plains, leaving the Ohio Valley on the periphery.
Given the uncertainty, have left some PoPs in for Monday afternoon
but will certainly need to be monitored for model changes over the
next day or two. Any precipitation that does fire up will be in the
form of thunderstorms. It should be dry otherwise through Wednesday.
Temperatures look to linger near normal, reaching the mid 80s during
the days and the low 60s overnight.
&&
.Aviation (00Z TAF Issuance)...
Updated at 740 PM EDT Thu May 31 2012
Numerous thunderstorms will continue at BWG and LEX from the 00z to
the 04z timeframe as a cold front is expected to move across central
Kentucky just before midnight. Expect low end MVFR visibilities and
ceilings within any thunderstorms.
At SDF light showers, with some occasional embedded thunderstorms,
will continue through 03z with associated MVFR flying conditions.
After 04z, only some light showers are expected to continue off an
on through around 10z. These showers will only reduce visibilities
to 4 to 5sm. Ceilings will remain consistently in the MVFR range
through at least 16z Friday as a strato-cu deck arrives over the
terminals. After 16z, ceilings will rise to VFR.
Southwest winds around 5 to 10kt will switch to the west as low
pressure moves north of LEX towards 06z. West winds of 12kt to 15KT
will develop after 08z and continue through Friday afternoon. West
winds may occasionally gust up to 25 mph late Friday morning or
afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........EER
Short Term.......JSD
Long Term........LG
Aviation.........JSD
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
125 PM EDT WED MAY 30 2012
.SYNOPSIS...
DRIER AND COOLER CONDITIONS CAN BE EXPECTED THROUGH THURSDAY AS
HIGH PRESSURE PASSES NORTH OF THE AREA. LOW PRESSURE WILL APPROACH
FROM THE WEST THURSDAY NIGHT AND BRING SHOWERS AND THUNDERSTORMS
TO THE AREA THROUGH FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
ADJUSTED SKY GRIDS AND BOOSTED TEMPERATURE GRIDS A COUPLE OF
DEGREES BASED ON CURRENT VISIBLE SATELLITE AND SURFACE
OBSERVATION TRENDS.
THE LATEST RAP ANALYSIS INDICATES A 300MB 100KT JET AXIS PUSHING
NORTHEAST OF THE AREA WITH A ZONAL MID-LEVEL FLOW IN ITS WAKE. AT
THE SURFACE, A 1000MB LOW IS LOCATED ACROSS QUEBEC WITH A COLD FRONT
EXTENDING SOUTHWEST OF THIS FEATURE ACROSS LAKE ERIE AND INTO OHIO.
THE FRONT IS MOST INDICATIVE BY ITS WIND SHIFT AND TD GRADIENT.
THE UPPER OHIO VALLEY WILL BE IN A ZONAL MID-LEVEL FLOW TODAY
AS THE FRONT PUSHES OFF THE EAST COAST AND HIGH PRESSURE BEGINS TO
BUILD IN FROM THE UPPER MIDWEST. SOME DIURNAL CUMULUS WILL DEVELOP
WITH A MOSTLY SUNNY DAY EXPECTED. WINDS WILL SHIFT TO NORTHWESTERLY
WITH THE PRESSURE GRADIENT TIGHTENING SLIGHTLY AND DIURNAL MIXING
ALLOWING FOR GUSTS TO 20 TO 25KTS. HIGHS ARE A FEW DEGREES COOLER
THAN A MAV/MET BLEND, RANGING FROM THE MID 70S ALONG THE I-80
CORRIDOR AND EASTERN RIDGES TO THE LOWER 80S IN PORTIONS OF NORTH-
CENTRAL WV AND EASTERN OHIO.
HIGH PRESSURE ACROSS THE UPPER MIDWEST WILL EXTEND SOUTHEASTWARD
INTO THE UPPER OHIO VALLEY ON WEDNESDAY NIGHT. THIS WILL PROVIDE A
REINFORCEMENT OF COOLER AIR INTO THE AREA. WITH A DRIER AIR MASS
SETTLED IN ACROSS THE REGION, 5-10 DEGREES TD DEPRESSIONS WILL
INHIBIT FOG DEVELOPMENT FOR THE MAJORITY. LOW TEMPS WILL BE
NOTICEABLY COOLER, CLOSER TO SEASONAL NORMALS IN THE UPPER 40S TO
LOWER 50S ACROSS THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
GFS/ECMWF ARE IN AGREEMENT THAT A ZONAL MID-LEVEL FLOW WILL CONTINUE
AS THE SURFACE HIGH PASSES NORTH OF THE AREA. THIS WILL ALLOW FOR
ANOTHER DRY DAY ON THURSDAY. THE COOLER NAM IS CONSIDERED TO BE AN
OUTLIER FOR HIGH TEMPS, WITH GFS/ECMWF INDICATING 850 TEMPS AT
7-10C. THIS WILL YIELD HIGHS TEMPS AROUND SEASONAL NORMS, IN THE
LOWER TO MID 70S ACROSS THE AREA.
A CONSENSUS OF OPERATIONAL MODELS INDICATES THAT A CLOSED LOW
WILL PIVOT FROM THE UPPER MIDWEST TO THE GREAT LAKES THURSDAY
NIGHT INTO FRIDAY. THIS FEATURE WILL HELP DIRECT A SURFACE LOW
FROM THE LOWER OHIO VALLEY INTO THE EASTERN GREAT LAKES THROUGH
THIS PERIOD. 700MB OMEGA FIELDS SUPPORT SYNOPTIC SCALE LIFT
PUSHING INTO THE AREA FROM THE WEST THURSDAY NIGHT AHEAD OF A
FRONTAL BOUNDARY. THIS WILL BRING A FAIRLY WIDESPREAD AREA OF RAIN
INTO THE AREA BY FRIDAY MORNING.
RAIN WILL REMAIN LIKELY AND INCREASE TO CATEGORICAL THROUGH THE
DAY ON FRIDAY AS A FRONTAL BOUNDARY PUSHES THROUGH THE AREA.
CONVERGENCE ALONG THE FRONT ALONG WITH GFS/NAM INDICATING A WEDGE
OF MODERATE SBCAPE WORKING INTO THE AREA BY 18Z FRIDAY SUPPORT THE
CHANCE OF THUNDER. TOTAL QPF WITH THIS SYSTEM WILL BE A HALF OF AN
INCH TO AN INCH FROM THURSDAY NIGHT INTO FRIDAY. RAIN-COOLED AIR
AND CLOUD COVERAGE WILL LIMIT TEMPS TO THE LOWER TO MID 70S ACROSS
THE AREA DESPITE WARM AIR ADVECTION AHEAD OF THE FRONT EARLY IN
THE DAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FORECAST IS CLOSEST TO A ECMWF/GFSE BLEND THROUGH THIS PERIOD.
LOOK FOR THE MERCURY TO STAY IN THE 60S FOR MOST LOCATIONS ON
SATURDAY AS H500 LOW SWINGS THROUGH THE GREAT LAKES AREA. AS THE
UPPER LOW MOVES OUT...A FULL LATITUDE TROF REMAINS FOR THE BALANCE
OF THE FORECAST WITH NORTHWEST FLOW OVER THE REGION. TEMPERATURES
RETURN CLOSER TO NORMAL MONDAY AND MODERATE TO 5 TO 10 DEGREES
ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD.
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
VFR CONDITIONS SHOULD CONTINUE WEDNESDAY NIGHT AND THURSDAY. LOW
PRESSURE AND ASSOCIATED UPPER H500 LOW APPROACHES LATE THURSDAY
NIGHT AND WILL SPREAD PRECIPITATION AND RESTRICTIONS ACROSS REGION
FRIDAY INTO SATURDAY. GRADUAL IMPROVEMENT FOR SUNDAY AS UPPER LOW
EXITS AREA.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
959 AM EDT WED MAY 30 2012
.SYNOPSIS...
DRIER AND COOLER CONDITIONS CAN BE EXPECTED THROUGH THURSDAY AS
HIGH PRESSURE PASSES NORTH OF THE AREA. LOW PRESSURE WILL APPROACH
FROM THE WEST THURSDAY NIGHT AND BRING SHOWERS AND THUNDERSTORMS
TO THE AREA THROUGH FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
ADJUSTED SKY AND TEMPERATURE GRIDS BASED ON CURRENT VISIBLE
SATELLITE AND SURFACE OBSERVATION TRENDS.
THE LATEST RAP ANALYSIS INDICATES A 300MB 100KT JET AXIS PUSHING
NORTHEAST OF THE AREA WITH A ZONAL MID-LEVEL FLOW IN ITS WAKE. AT
THE SURFACE, A 1000MB LOW IS LOCATED ACROSS QUEBEC WITH A COLD FRONT
EXTENDING SOUTHWEST OF THIS FEATURE ACROSS LAKE ERIE AND INTO OHIO.
THE FRONT IS MOST INDICATIVE BY ITS WIND SHIFT AND TD GRADIENT.
THE UPPER OHIO VALLEY WILL BE IN A ZONAL MID-LEVEL FLOW TODAY
AS THE FRONT PUSHES OFF THE EAST COAST AND HIGH PRESSURE BEGINS TO
BUILD IN FROM THE UPPER MIDWEST. SOME DIURNAL CUMULUS WILL DEVELOP
WITH A MOSTLY SUNNY DAY EXPECTED. WINDS WILL SHIFT TO NORTHWESTERLY
WITH THE PRESSURE GRADIENT TIGHTENING SLIGHTLY AND DIURNAL MIXING
ALLOWING FOR GUSTS TO 20 TO 25KTS. HIGHS ARE A FEW DEGREES COOLER
THAN A MAV/MET BLEND, RANGING FROM THE MID 70S ALONG THE I-80
CORRIDOR AND EASTERN RIDGES TO THE LOWER 80S IN PORTIONS OF NORTH-
CENTRAL WV AND EASTERN OHIO.
HIGH PRESSURE ACROSS THE UPPER MIDWEST WILL EXTEND SOUTHEASTWARD
INTO THE UPPER OHIO VALLEY ON WEDNESDAY NIGHT. THIS WILL PROVIDE A
REINFORCEMENT OF COOLER AIR INTO THE AREA. WITH A DRIER AIR MASS
SETTLED IN ACROSS THE REGION, 5-10 DEGREES TD DEPRESSIONS WILL
INHIBIT FOG DEVELOPMENT FOR THE MAJORITY. LOW TEMPS WILL BE
NOTICEABLY COOLER, CLOSER TO SEASONAL NORMALS IN THE UPPER 40S TO
LOWER 50S ACROSS THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
GFS/ECMWF ARE IN AGREEMENT THAT A ZONAL MID-LEVEL FLOW WILL CONTINUE
AS THE SURFACE HIGH PASSES NORTH OF THE AREA. THIS WILL ALLOW FOR
ANOTHER DRY DAY ON THURSDAY. THE COOLER NAM IS CONSIDERED TO BE AN
OUTLIER FOR HIGH TEMPS, WITH GFS/ECMWF INDICATING 850 TEMPS AT
7-10C. THIS WILL YIELD HIGHS TEMPS AROUND SEASONAL NORMS, IN THE
LOWER TO MID 70S ACROSS THE AREA.
A CONSENSUS OF OPERATIONAL MODELS INDICATES THAT A CLOSED LOW
WILL PIVOT FROM THE UPPER MIDWEST TO THE GREAT LAKES THURSDAY
NIGHT INTO FRIDAY. THIS FEATURE WILL HELP DIRECT A SURFACE LOW
FROM THE LOWER OHIO VALLEY INTO THE EASTERN GREAT LAKES THROUGH
THIS PERIOD. 700MB OMEGA FIELDS SUPPORT SYNOPTIC SCALE LIFT
PUSHING INTO THE AREA FROM THE WEST THURSDAY NIGHT AHEAD OF A
FRONTAL BOUNDARY. THIS WILL BRING A FAIRLY WIDESPREAD AREA OF RAIN
INTO THE AREA BY FRIDAY MORNING.
RAIN WILL REMAIN LIKELY AND INCREASE TO CATEGORICAL THROUGH THE
DAY ON FRIDAY AS A FRONTAL BOUNDARY PUSHES THROUGH THE AREA.
CONVERGENCE ALONG THE FRONT ALONG WITH GFS/NAM INDICATING A WEDGE
OF MODERATE SBCAPE WORKING INTO THE AREA BY 18Z FRIDAY SUPPORT THE
CHANCE OF THUNDER. TOTAL QPF WITH THIS SYSTEM WILL BE A HALF OF AN
INCH TO AN INCH FROM THURSDAY NIGHT INTO FRIDAY. RAIN-COOLED AIR
AND CLOUD COVERAGE WILL LIMIT TEMPS TO THE LOWER TO MID 70S ACROSS
THE AREA DESPITE WARM AIR ADVECTION AHEAD OF THE FRONT EARLY IN
THE DAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FORECAST IS CLOSEST TO A ECMWF/GFSE BLEND THROUGH THIS PERIOD.
LOOK FOR THE MERCURY TO STAY IN THE 60S FOR MOST LOCATIONS ON
SATURDAY AS H500 LOW SWINGS THROUGH THE GREAT LAKES AREA. AS THE
UPPER LOW MOVES OUT...A FULL LATITUDE TROF REMAINS FOR THE BALANCE
OF THE FORECAST WITH NORTHWEST FLOW OVER THE REGION. TEMPERATURES
RETURN CLOSER TO NORMAL MONDAY AND MODERATE TO 5 TO 10 DEGREES
ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
AREAS OF MVFR CEILINGS ALONG THE RIDGES SHOULD LIFT AND SCATTER
OUT BY LATE MORNING AS HIGH PRESSURE BRINGS DRIER AIR INTO THE
REGION.
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
VFR CONDITIONS SHOULD CONTINUE WEDNESDAY NIGHT AND THURSDAY. LOW
PRESSURE AND ASSOCIATED UPPER H500 LOW APPROACHES LATE THURSDAY
NIGHT AND WILL SPREAD PRECIPITATION AND RESTRICTIONS ACROSS REGION
FRIDAY INTO SATURDAY. GRADUAL IMPROVEMENT FOR SUNDAY AS UPPER LOW
EXITS AREA.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
602 AM EDT WED MAY 30 2012
.SYNOPSIS...
A DRIER AND COOLER MID-WEEK CAN BE EXPECTED AS HIGH PRESSURE
PASSES NORTH OF THE AREA. LOW PRESSURE WILL APPROACH FROM THE WEST
THURSDAY NIGHT AND BRING RAIN TO THE AREA THROUGH FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
A QUICK UPDATE HAS BEEN ISSUED THIS MORNING TO DECREASE THE
MORNING SKY GRIDS AS SKIES ARE CLEARING FROM THE WEST.
THE LATEST RAP ANALYSIS INDICATES A 300MB 100KT JET AXIS PUSHING
NORTHEAST OF THE AREA WITH A ZONAL MID-LEVEL FLOW IN ITS WAKE. AT
THE SURFACE, A 1000MB LOW IS LOCATED ACROSS QUEBEC WITH A COLD FRONT
EXTENDING SOUTHWEST OF THIS FEATURE ACROSS LAKE ERIE AND INTO OHIO.
THE FRONT IS MOST INDICATIVE BY ITS WIND SHIFT AND TD GRADIENT.
THE UPPER OHIO VALLEY WILL BE IN A ZONAL MID-LEVEL FLOW TODAY
AS THE FRONT PUSHES OFF THE EAST COAST AND HIGH PRESSURE BEGINS TO
BUILD IN FROM THE UPPER MIDWEST. SOME DIURNAL CUMULUS WILL DEVELOP
WITH A MOSTLY SUNNY DAY EXPECTED. WINDS WILL SHIFT TO NORTHWESTERLY
WITH THE PRESSURE GRADIENT TIGHTENING SLIGHTLY AND DIURNAL MIXING
ALLOWING FOR GUSTS TO 20 TO 25KTS. HIGHS ARE A FEW DEGREES COOLER
THAN A MAV/MET BLEND, RANGING FROM THE MID 70S ALONG THE I-80
CORRIDOR AND EASTERN RIDGES TO THE LOWER 80S IN PORTIONS OF NORTH-
CENTRAL WV AND EASTERN OHIO.
HIGH PRESSURE ACROSS THE UPPER MIDWEST WILL EXTEND SOUTHEASTWARD
INTO THE UPPER OHIO VALLEY ON WEDNESDAY NIGHT. THIS WILL PROVIDE A
REINFORCEMENT OF COOLER AIR INTO THE AREA. WITH A DRIER AIR MASS
SETTLED IN ACROSS THE REGION, 5-10 DEGREES TD DEPRESSIONS WILL
INHIBIT FOG DEVELOPMENT FOR THE MAJORITY. LOW TEMPS WILL BE
NOTICEABLY COOLER, CLOSER TO SEASONAL NORMALS IN THE UPPER 40S TO
LOWER 50S ACROSS THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
GFS/ECMWF ARE IN AGREEMENT THAT A ZONAL MID-LEVEL FLOW WILL CONTINUE
AS THE SURFACE HIGH PASSES NORTH OF THE AREA. THIS WILL ALLOW FOR
ANOTHER DRY DAY ON THURSDAY. THE COOLER NAM IS CONSIDERED TO BE AN
OUTLIER FOR HIGH TEMPS, WITH GFS/ECMWF INDICATING 850 TEMPS AT
7-10C. THIS WILL YIELD HIGHS TEMPS AROUND SEASONAL NORMS, IN THE
LOWER TO MID 70S ACROSS THE AREA.
A CONSENSUS OF OPERATIONAL MODELS INDICATES THAT A CLOSED LOW
WILL PIVOT FROM THE UPPER MIDWEST TO THE GREAT LAKES THURSDAY
NIGHT INTO FRIDAY. THIS FEATURE WILL HELP DIRECT A SURFACE LOW
FROM THE LOWER OHIO VALLEY INTO THE EASTERN GREAT LAKES THROUGH
THIS PERIOD. 700MB OMEGA FIELDS SUPPORT SYNOPTIC SCALE LIFT
PUSHING INTO THE AREA FROM THE WEST THURSDAY NIGHT AHEAD OF A
FRONTAL BOUNDARY. THIS WILL BRING A FAIRLY WIDESPREAD AREA OF RAIN
INTO THE AREA BY FRIDAY MORNING.
RAIN WILL REMAIN LIKELY AND INCREASE TO CATEGORICAL THROUGH THE
DAY ON FRIDAY AS A FRONTAL BOUNDARY PUSHES THROUGH THE AREA.
CONVERGENCE ALONG THE FRONT ALONG WITH GFS/NAM INDICATING A WEDGE
OF MODERATE SBCAPE WORKING INTO THE AREA BY 18Z FRIDAY SUPPORT THE
CHANCE OF THUNDER. TOTAL QPF WITH THIS SYSTEM WILL BE A HALF OF AN
INCH TO AN INCH FROM THURSDAY NIGHT INTO FRIDAY. RAIN-COOLED AIR
AND CLOUD COVERAGE WILL LIMIT TEMPS TO THE LOWER TO MID 70S ACROSS
THE AREA DESPITE WARM AIR ADVECTION AHEAD OF THE FRONT EARLY IN
THE DAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FORECAST IS CLOSEST TO A ECMWF/GFSE BLEND THROUGH THIS PERIOD.
LOOK FOR THE MERCURY TO STAY IN THE 60S FOR MOST LOCATIONS ON
SATURDAY AS H500 LOW SWINGS THROUGH THE GREAT LAKES AREA. AS THE
UPPER LOW MOVES OUT...A FULL LATITUDE TROF REMAINS FOR THE BALANCE
OF THE FORECAST WITH NORTHWEST FLOW OVER THE REGION. TEMPERATURES
RETURN CLOSER TO NORMAL MONDAY AND MODERATE TO 5 TO 10 DEGREES
ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
-SHRA HAVE NOW PROGRESSED TO THE SE OF ALL THE SITES TONIGHT. THE
REST OF THE NIGHT SHOULD BE DRY AT ALL SITES. THERE IS LIKELY TO
BE A RACE BETWEEN CLEARING FROM THE WEST AND LOWER SURFACE
DEWPOINTS THAT WILL PLAY OUT AT ALL SITES TO DETERMINE HOW
WIDESPREAD FOG IS OVERNIGHT INTO WEDNESDAY MORNING. AT THIS
TIME...IT SEEMS MOST LIKELY THE MAJORITY OF THE FOG SHOULD BE AT
THE EASTERN SITES FROM KDUJ SOUTH TO KMGW AND EASTWARD. THERE WILL
LIKELY BE PATCHES OF LIFR FOG IN THAT AREA...HOWEVER PINPOINTING
WHETHER IT WILL OCCUR AT ANY PARTICULAR TERMINAL IS
DIFFICULT...THOUGH KDUJ SEEMS THE MOST LIKELY AT THE MOMENT.
OTHERWISE...GENERALLY AT LEAST MVFR VIS RESTRICTIONS ARE EXPECTED
THROUGH THE NIGHT DUE TO LINGERING LOW LEVEL MOISTURE AND CLEARING
MID AND HIGH CLOUDS. VFR CONDITIONS ARE LIKELY TO RETURN
EVERYWHERE BY LATE MORNING WEDNESDAY. FRIES
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
VFR CONDITIONS WEDNESDAY NIGHT AND THURSDAY. LOW PRESSURE AND
ASSOCIATED UPPER H500 LOW APPROACHES LATE THURSDAY NIGHT AND WILL
SPREAD PRECIPITATION AND RESTRICTIONS ACROSS REGION FRIDAY INTO
SATURDAY. GRADUAL IMPROVEMENT FOR SUNDAY AS UPPER LOW EXITS AREA.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
453 AM EDT WED MAY 30 2012
.SYNOPSIS...
A DRIER AND COOLER MID-WEEK CAN BE EXPECTED IN THE WAKE OF A COLD
FRONT AS HIGH PRESSURE PASSES NORTH OF THE AREA. LOW PRESSURE WILL
APPROACH FROM THE WEST THURSDAY NIGHT AND BRING RAIN TO THE AREA
THROUGH FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RAP ANALYSIS INDICATES A 300MB 100KT JET AXIS PUSHING
NORTHEAST OF THE AREA WITH A ZONAL MID-LEVEL FLOW IN ITS WAKE. AT
THE SURFACE, A 1000MB LOW IS LOCATED ACROSS QUEBEC WITH A COLD FRONT
EXTENDING SOUTHWEST OF THIS FEATURE ACROSS LAKE ERIE AND INTO OHIO.
THE FRONT IS MOST INDICATIVE BY ITS WIND SHIFT AND TD GRADIENT.
THE UPPER OHIO VALLEY WILL BE IN A ZONAL MID-LEVEL FLOW TODAY
AS THE FRONT PUSHES OFF THE EAST COAST AND HIGH PRESSURE BEGINS TO
BUILD IN FROM THE UPPER MIDWEST. SOME DIURNAL CUMULUS WILL DEVELOP
WITH A MOSTLY SUNNY DAY EXPECTED. WINDS WILL SHIFT TO NORTHWESTERLY
WITH THE PRESSURE GRADIENT TIGHTENING SLIGHTLY AND DIURNAL MIXING
ALLOWING FOR GUSTS TO 20 TO 25KTS. HIGHS ARE A FEW DEGREES COOLER
THAN A MAV/MET BLEND, RANGING FROM THE MID 70S ALONG THE I-80
CORRIDOR AND EASTERN RIDGES TO THE LOWER 80S IN PORTIONS OF NORTH-
CENTRAL WV AND EASTERN OHIO.
HIGH PRESSURE ACROSS THE UPPER MIDWEST WILL EXTEND SOUTHEASTWARD
INTO THE UPPER OHIO VALLEY ON WEDNESDAY NIGHT. THIS WILL PROVIDE A
REINFORCEMENT OF COOLER AIR INTO THE AREA. WITH A DRIER AIR MASS
SETTLED IN ACROSS THE REGION, 5-10 DEGREES TD DEPRESSIONS WILL
INHIBIT FOG DEVELOPMENT FOR THE MAJORITY. LOW TEMPS WILL BE
NOTICEABLY COOLER, CLOSER TO SEASONAL NORMALS IN THE UPPER 40S TO
LOWER 50S ACROSS THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
GFS/ECMWF ARE IN AGREEMENT THAT A ZONAL MID-LEVEL FLOW WILL CONTINUE
AS THE SURFACE HIGH PASSES NORTH OF THE AREA. THIS WILL ALLOW FOR
ANOTHER DRY DAY ON THURSDAY. THE COOLER NAM IS CONSIDERED TO BE AN
OUTLIER FOR HIGH TEMPS, WITH GFS/ECMWF INDICATING 850 TEMPS AT
7-10C. THIS WILL YIELD HIGHS TEMPS AROUND SEASONAL NORMS, IN THE
LOWER TO MID 70S ACROSS THE AREA.
A CONSENSUS OF OPERATIONAL MODELS INDICATES THAT A CLOSED LOW
WILL PIVOT FROM THE UPPER MIDWEST TO THE GREAT LAKES THURSDAY
NIGHT INTO FRIDAY. THIS FEATURE WILL HELP DIRECT A SURFACE LOW
FROM THE LOWER OHIO VALLEY INTO THE EASTERN GREAT LAKES THROUGH
THIS PERIOD. 700MB OMEGA FIELDS SUPPORT SYNOPTIC SCALE LIFT
PUSHING INTO THE AREA FROM THE WEST THURSDAY NIGHT AHEAD OF A
FRONTAL BOUNDARY. THIS WILL BRING A FAIRLY WIDESPREAD AREA OF RAIN
INTO THE AREA BY FRIDAY MORNING.
RAIN WILL REMAIN LIKELY AND INCREASE TO CATEGORICAL THROUGH THE
DAY ON FRIDAY AS A FRONTAL BOUNDARY PUSHES THROUGH THE AREA.
CONVERGENCE ALONG THE FRONT ALONG WITH GFS/NAM INDICATING A WEDGE
OF MODERATE SBCAPE WORKING INTO THE AREA BY 18Z FRIDAY SUPPORT THE
CHANCE OF THUNDER. TOTAL QPF WITH THIS SYSTEM WILL BE A HALF OF AN
INCH TO AN INCH FROM THURSDAY NIGHT INTO FRIDAY. RAIN-COOLED AIR
AND CLOUD COVERAGE WILL LIMIT TEMPS TO THE LOWER TO MID 70S ACROSS
THE AREA DESPITE WARM AIR ADVECTION AHEAD OF THE FRONT EARLY IN
THE DAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FORECAST IS CLOSEST TO A ECMWF/GFSE BLEND THROUGH THIS PERIOD.
LOOK FOR THE MERCURY TO STAY IN THE 60S FOR MOST LOCATIONS ON
SATURDAY AS H500 LOW SWINGS THROUGH THE GREAT LAKES AREA. AS THE
UPPER LOW MOVES OUT...A FULL LATITUDE TROF REMAINS FOR THE BALANCE
OF THE FORECAST WITH NORTHWEST FLOW OVER THE REGION. TEMPERATURES
RETURN CLOSER TO NORMAL MONDAY AND MODERATE TO 5 TO 10 DEGREES
ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
-SHRA HAVE NOW PROGRESSED TO THE SE OF ALL THE SITES TONIGHT. THE
REST OF THE NIGHT SHOULD BE DRY AT ALL SITES. THERE IS LIKELY TO
BE A RACE BETWEEN CLEARING FROM THE WEST AND LOWER SURFACE
DEWPOINTS THAT WILL PLAY OUT AT ALL SITES TO DETERMINE HOW
WIDESPREAD FOG IS OVERNIGHT INTO WEDNESDAY MORNING. AT THIS
TIME...IT SEEMS MOST LIKELY THE MAJORITY OF THE FOG SHOULD BE AT
THE EASTERN SITES FROM KDUJ SOUTH TO KMGW AND EASTWARD. THERE WILL
LIKELY BE PATCHES OF LIFR FOG IN THAT AREA...HOWEVER PINPOINTING
WHETHER IT WILL OCCUR AT ANY PARTICULAR TERMINAL IS
DIFFICULT...THOUGH KDUJ SEEMS THE MOST LIKELY AT THE MOMENT.
OTHERWISE...GENERALLY AT LEAST MVFR VIS RESTRICTIONS ARE EXPECTED
THROUGH THE NIGHT DUE TO LINGERING LOW LEVEL MOISTURE AND CLEARING
MID AND HIGH CLOUDS. VFR CONDITIONS ARE LIKELY TO RETURN
EVERYWHERE BY LATE MORNING WEDNESDAY. FRIES
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
VFR CONDITIONS WEDNESDAY NIGHT AND THURSDAY. LOW PRESSURE AND
ASSOCIATED UPPER H500 LOW APPROACHES LATE THURSDAY NIGHT AND WILL
SPREAD PRECIPITATION AND RESTRICTIONS ACROSS REGION FRIDAY INTO
SATURDAY. GRADUAL IMPROVEMENT FOR SUNDAY AS UPPER LOW EXITS AREA.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1053 AM EDT WED MAY 30 2012
.SYNOPSIS...
ISSUED AT 328 AM EDT WED MAY 30 2012
ANOTHER COLD FRONT WILL PASS THROUGH THE REGION TODAY. ISOLATED
SHOWERS ARE POSSIBLE MAINLY NORTH OF I-94. AS CLOUDS CLEAR TONIGHT
TEMPERATURES WILL FALL INTO THE MID 30S OVER INLAND AREAS NORTH OF
M-20 AND FROST IS EXPECTED. CHILLY WEATHER WILL CONTINUE INTO
SATURDAY BEFORE A WARMING TREND DEVELOPS. THURSDAY NIGHT AND
FRIDAY WILL BE RAINY AS LOW PRESSURE MOVES FROM THE SOUTHERN
PLAINS TO THE GREAT LAKES.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
FORECAST CONCERNS DEAL WITH FROST POTENTIAL TONIGHT AND
PRECIPITATION TRENDS THURSDAY.
* FROST ADVISORY OVERNIGHT TONIGHT NORTHEAST 6 COUNTIES.
IR LOOP SHOWS STRATOCU ADVECTING EWD FROM WISCONSIN ATTM. WEAK
SHORT WAVES MOVING AROUND THE UPPER TROUGH WILL INTERACT WITH THE
AFOREMENTIONED REINFORCING SHOT OF COLDER AIR TODAY TO CREATE A
BROKEN DECK OF STRATO CU FROM MID MORNING THROUGH MID AFTERNOON.
LATEST HRRR ALSO SHOWS SOME LIGHT SHOWERS MOVING INTO THE CWA TOO. WE
SAW THIS OCCUR IN WISCONSIN YESTERDAY AND SO ADDED ISOLD SHRA TO
THE GRIDS MAINLY NORTH OF I-94.
HIGH PRESSURE OVER THE UPPER MIDWEST WILL RESULT IN CLEARING SKIES
TONIGHT. LIGHT WINDS WILL HELP TEMPS FALL INTO THE MID 30S NORTH
OF M-20 TONIGHT. ISSUED A FROST ADVISORY FOR THE NORTHEAST 6
COUNTIES FROM 06Z-12Z. IT/S NOT A SLAM DUNK THOUGH AS STRATOCU
COULD LINGER A BIT LONGER IN THAT AREA AND WINDS MAY NOT BE CALM
SINCE THE CENTER OF THE HIGH WON/T BE OVERHEAD.
CLOUDS WILL BE ON THE INCREASE THURSDAY AS LOW PRESSURE IN TEXAS
MAKES A RUN AT THAT THE GREAT LAKES. THIS HAS BEEN WELL ADVERTISED
BY THE MODELS FOR A FEW DAYS AND SO CONFIDENCE IS PRETTY HIGH THAT
WE/LL SEE SOME RAIN FROM IT. CURRENT MODEL TRENDS SUGGEST THAT
PCPN WILL MOVE INTO THE FAR SOUTHWEST CWA AFTER 18Z THURSDAY. WE
INCREASED POPS ACCORDINGLY.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
THE LONG TERM PERIOD BEGINS WITH LOW PRESSURE TRACKING FROM THE OHIO
VALLEY NORTHEAST TO LAKE ERIE THURSDAY NIGHT. THE LOW SLOWLY LIFTS
NORTHWARD OVER LAKE HURON INTO ONTARIO FRIDAY INTO SATURDAY. IT
LOOKS LIKE A DAMP AND COOL PERIOD FROM THURSDAY NIGHT INTO SATURDAY
MORNING. HIGHS ON FRIDAY WILL ONLY TOP OUT IN THE UPPER 50S TO
AROUND 60. SLIGHTLY WARMER READINGS ON SATURDAY IN THE MIDDLE 60S.
UPPER TROUGHING ACTUALLY LINGERS THROUGH THE WEEKEND AND INTO EARLY
NEXT WEEK. LOWER MICHIGAN IS LOCATED IN AN AREA IN THE UPPER PATTERN
EARLY NEXT WEEK WHERE WE WILL BE IN A TRANSITION FROM TROUGHING TO
RIDGING. NOT CONFIDENT EXACTLY WHERE WE WILL BE YET...BUT THE
EUROPEAN WOULD INDICATE A BIT MORE IN THE WAY OF TROUGHING. HAVE
SMALL POPS FOR SHOWERS IN THE FORECAST FOR SUNDAY NIGHT - MONDAY
NIGHT. THE EURO HAS ANOTHER SHORTWAVE DIVING THROUGH THE AREA DURING
THIS TIME...SO FEEL THE SMALL POPS STILL LOOK OK. WITH TIME WE MAY
NEED TO NUDGE TEMPS FOR SUNDAY THROUGH TUESDAY DOWN A TAD IF TRENDS
CONTINUE TOWARD UPPER TROUGHING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 744 AM EDT WED MAY 30 2012
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF PERIOD. BKN-OVC
VFR CEILINGS ARE EXPECTED TODAY WITH BASES IN THE 3500-7000FT
RANGE. SCATTERED RAIN SHOWERS ARE POSSIBLE THIS AFTERNOON. GIVEN
LOW COVERAGE USED VCSH IN THE TAFS. WINDS WILL BE FROM THE WEST-
NORTHWEST TODAY AT 08-15 KNOTS...BECOMING LIGHT TONIGHT.
&&
.MARINE...
ISSUED AT 1050 AM EDT WED MAY 30 2012
THE COLDER AIR MOVING ACROSS THE LAKE WILL CAUSE SOME INCREASE IN
THE WAVES THIS AFTERNOON. WINDS ARE NOT EXPECTED TO BE HIGH ENOUGH
TO CAUSE THE WAVES TO REACH SMALL CRAFT ADVISORY CRITERIA.
THE PRESSURE GRADIENT WEAKENS AHEAD OF THE NEXT STORM AND THE FLOW
BECOMES OFFSHORE...SUGGESTING WAVES WILL REMAIN LOW.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT WED MAY 30 2012
RAIN IS EXPECTED THURSDAY AFTERNOON THROUGH FRIDAY. A HALF TO AN
INCH OF PCPN IS POSSIBLE SOUTH OF I-96. THIS WILL LIKELY RESULT IN
MINOR RISES ON AREA RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FROST ADVISORY FROM 2 AM TO 8 AM EDT THURSDAY FOR MIZ038>040-
044>046.
LM...NONE.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...93
MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
745 AM EDT WED MAY 30 2012
.SYNOPSIS...
ISSUED AT 328 AM EDT WED MAY 30 2012
ANOTHER COLD FRONT WILL PASS THROUGH THE REGION TODAY. ISOLATED
SHOWERS ARE POSSIBLE MAINLY NORTH OF I-94. AS CLOUDS CLEAR TONIGHT
TEMPERATURES WILL FALL INTO THE MID 30S OVER INLAND AREAS NORTH OF
M-20 AND FROST IS EXPECTED. CHILLY WEATHER WILL CONTINUE INTO
SATURDAY BEFORE A WARMING TREND DEVELOPS. THURSDAY NIGHT AND
FRIDAY WILL BE RAINY AS LOW PRESSURE MOVES FROM THE SOUTHERN
PLAINS TO THE GREAT LAKES.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
FORECAST CONCERNS DEAL WITH FROST POTENTIAL TONIGHT AND
PRECIPITATION TRENDS THURSDAY.
* FROST ADVISORY OVERNIGHT TONIGHT NORTHEAST 6 COUNTIES.
IR LOOP SHOWS STRATOCU ADVECTING EWD FROM WISCONSIN ATTM. WEAK
SHORT WAVES MOVING AROUND THE UPPER TROUGH WILL INTERACT WITH THE
AFOREMENTIONED REINFORCING SHOT OF COLDER AIR TODAY TO CREATE A
BROKEN DECK OF STRATO CU FROM MID MORNING THROUGH MID AFTERNOON.
LATEST HRRR ALSO SHOWS SOME LIGHT SHOWERS MOVING INTO THE CWA TOO. WE
SAW THIS OCCUR IN WISCONSIN YESTERDAY AND SO ADDED ISOLD SHRA TO
THE GRIDS MAINLY NORTH OF I-94.
HIGH PRESSURE OVER THE UPPER MIDWEST WILL RESULT IN CLEARING SKIES
TONIGHT. LIGHT WINDS WILL HELP TEMPS FALL INTO THE MID 30S NORTH
OF M-20 TONIGHT. ISSUED A FROST ADVISORY FOR THE NORTHEAST 6
COUNTIES FROM 06Z-12Z. IT/S NOT A SLAM DUNK THOUGH AS STRATOCU
COULD LINGER A BIT LONGER IN THAT AREA AND WINDS MAY NOT BE CALM
SINCE THE CENTER OF THE HIGH WON/T BE OVERHEAD.
CLOUDS WILL BE ON THE INCREASE THURSDAY AS LOW PRESSURE IN TEXAS
MAKES A RUN AT THAT THE GREAT LAKES. THIS HAS BEEN WELL ADVERTISED
BY THE MODELS FOR A FEW DAYS AND SO CONFIDENCE IS PRETTY HIGH THAT
WE/LL SEE SOME RAIN FROM IT. CURRENT MODEL TRENDS SUGGEST THAT
PCPN WILL MOVE INTO THE FAR SOUTHWEST CWA AFTER 18Z THURSDAY. WE
INCREASED POPS ACCORDINGLY.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
THE LONG TERM PERIOD BEGINS WITH LOW PRESSURE TRACKING FROM THE OHIO
VALLEY NORTHEAST TO LAKE ERIE THURSDAY NIGHT. THE LOW SLOWLY LIFTS
NORTHWARD OVER LAKE HURON INTO ONTARIO FRIDAY INTO SATURDAY. IT
LOOKS LIKE A DAMP AND COOL PERIOD FROM THURSDAY NIGHT INTO SATURDAY
MORNING. HIGHS ON FRIDAY WILL ONLY TOP OUT IN THE UPPER 50S TO
AROUND 60. SLIGHTLY WARMER READINGS ON SATURDAY IN THE MIDDLE 60S.
UPPER TROUGHING ACTUALLY LINGERS THROUGH THE WEEKEND AND INTO EARLY
NEXT WEEK. LOWER MICHIGAN IS LOCATED IN AN AREA IN THE UPPER PATTERN
EARLY NEXT WEEK WHERE WE WILL BE IN A TRANSITION FROM TROUGHING TO
RIDGING. NOT CONFIDENT EXACTLY WHERE WE WILL BE YET...BUT THE
EUROPEAN WOULD INDICATE A BIT MORE IN THE WAY OF TROUGHING. HAVE
SMALL POPS FOR SHOWERS IN THE FORECAST FOR SUNDAY NIGHT - MONDAY
NIGHT. THE EURO HAS ANOTHER SHORTWAVE DIVING THROUGH THE AREA DURING
THIS TIME...SO FEEL THE SMALL POPS STILL LOOK OK. WITH TIME WE MAY
NEED TO NUDGE TEMPS FOR SUNDAY THROUGH TUESDAY DOWN A TAD IF TRENDS
CONTINUE TOWARD UPPER TROUGHING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 744 AM EDT WED MAY 30 2012
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF PERIOD. BKN-OVC
VFR CEILINGS ARE EXPECTED TODAY WITH BASES IN THE 3500-7000FT
RANGE. SCATTERED RAIN SHOWERS ARE POSSIBLE THIS AFTERNOON. GIVEN
LOW COVERAGE USED VCSH IN THE TAFS. WINDS WILL BE FROM THE WEST-
NORTHWEST TODAY AT 08-15 KNOTS...BECOMING LIGHT TONIGHT.
&&
.MARINE...
ISSUED AT 328 AM EDT WED MAY 30 2012
NORTHWEST WINDS 10 TO 20 KNOTS WILL RESULT IN 1 TO 3 FOOT WAVES
TODAY.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT WED MAY 30 2012
RAIN IS EXPECTED THURSDAY AFTERNOON THROUGH FRIDAY. A HALF TO AN
INCH OF PCPN IS POSSIBLE SOUTH OF I-96. THIS WILL LIKELY RESULT IN
MINOR RISES ON AREA RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FROST ADVISORY FROM 2 AM TO 8 AM EDT THURSDAY FOR MIZ038>040-
044>046.
LM...NONE.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
329 AM EDT WED MAY 30 2012
.SYNOPSIS...
ISSUED AT 328 AM EDT WED MAY 30 2012
ANOTHER COLD FRONT WILL PASS THROUGH THE REGION TODAY. ISOLATED
SHOWERS ARE POSSIBLE MAINLY NORTH OF I-94. AS CLOUDS CLEAR TONIGHT
TEMPERATURES WILL FALL INTO THE MID 30S OVER INLAND AREAS NORTH OF
M-20 AND FROST IS EXPECTED. CHILLY WEATHER WILL CONTINUE INTO
SATURDAY BEFORE A WARMING TREND DEVELOPS. THURSDAY NIGHT AND
FRIDAY WILL BE RAINY AS LOW PRESSURE MOVES FROM THE SOUTHERN
PLAINS TO THE GREAT LAKES.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
FORECAST CONCERNS DEAL WITH FROST POTENTIAL TONIGHT AND
PRECIPITATION TRENDS THURSDAY.
* FROST ADVISORY OVERNIGHT TONIGHT NORTHEAST 6 COUNTIES.
IR LOOP SHOWS STRATOCU ADVECTING EWD FROM WISCONSIN ATTM. WEAK
SHORT WAVES MOVING AROUND THE UPPER TROUGH WILL INTERACT WITH THE
AFOREMENTIONED REINFORCING SHOT OF COLDER AIR TODAY TO CREATE A
BROKEN DECK OF STRATO CU FROM MID MORNING THROUGH MID AFTERNOON.
LATEST HRRR ALSO SHOWS SOME LIGHT SHOWERS MOVING INTO THE CWA TOO. WE
SAW THIS OCCUR IN WISCONSIN YESTERDAY AND SO ADDED ISOLD SHRA TO
THE GRIDS MAINLY NORTH OF I-94.
HIGH PRESSURE OVER THE UPPER MIDWEST WILL RESULT IN CLEARING SKIES
TONIGHT. LIGHT WINDS WILL HELP TEMPS FALL INTO THE MID 30S NORTH
OF M-20 TONIGHT. ISSUED A FROST ADVISORY FOR THE NORTHEAST 6
COUNTIES FROM 06Z-12Z. IT/S NOT A SLAM DUNK THOUGH AS STRATOCU
COULD LINGER A BIT LONGER IN THAT AREA AND WINDS MAY NOT BE CALM
SINCE THE CENTER OF THE HIGH WON/T BE OVERHEAD.
CLOUDS WILL BE ON THE INCREASE THURSDAY AS LOW PRESSURE IN TEXAS
MAKES A RUN AT THAT THE GREAT LAKES. THIS HAS BEEN WELL ADVERTISED
BY THE MODELS FOR A FEW DAYS AND SO CONFIDENCE IS PRETTY HIGH THAT
WE/LL SEE SOME RAIN FROM IT. CURRENT MODEL TRENDS SUGGEST THAT
PCPN WILL MOVE INTO THE FAR SOUTHWEST CWA AFTER 18Z THURSDAY. WE
INCREASED POPS ACCORDINGLY.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 AM EDT WED MAY 30 2012
THE LONG TERM PERIOD BEGINS WITH LOW PRESSURE TRACKING FROM THE OHIO
VALLEY NORTHEAST TO LAKE ERIE THURSDAY NIGHT. THE LOW SLOWLY LIFTS
NORTHWARD OVER LAKE HURON INTO ONTARIO FRIDAY INTO SATURDAY. IT
LOOKS LIKE A DAMP AND COOL PERIOD FROM THURSDAY NIGHT INTO SATURDAY
MORNING. HIGHS ON FRIDAY WILL ONLY TOP OUT IN THE UPPER 50S TO
AROUND 60. SLIGHTLY WARMER READINGS ON SATURDAY IN THE MIDDLE 60S.
UPPER TROUGHING ACTUALLY LINGERS THROUGH THE WEEKEND AND INTO EARLY
NEXT WEEK. LOWER MICHIGAN IS LOCATED IN AN AREA IN THE UPPER PATTERN
EARLY NEXT WEEK WHERE WE WILL BE IN A TRANSITION FROM TROUGHING TO
RIDGING. NOT CONFIDENT EXACTLY WHERE WE WILL BE YET...BUT THE
EUROPEAN WOULD INDICATE A BIT MORE IN THE WAY OF TROUGHING. HAVE
SMALL POPS FOR SHOWERS IN THE FORECAST FOR SUNDAY NIGHT - MONDAY
NIGHT. THE EURO HAS ANOTHER SHORTWAVE DIVING THROUGH THE AREA DURING
THIS TIME...SO FEEL THE SMALL POPS STILL LOOK OK. WITH TIME WE MAY
NEED TO NUDGE TEMPS FOR SUNDAY THROUGH TUESDAY DOWN A TAD IF TRENDS
CONTINUE TOWARD UPPER TROUGHING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 153 AM EDT WED MAY 30 2012
A BKN VFR DECK WILL DEVELOP THIS MORNING IN AS AN UPPER TROUGH
MOVES ACROSS THE CWA. THE CEILING WILL SCATTER BY LATE AFTERNOON
AND SKIES WILL BECOME CLEAR LATER THIS EVENING.
&&
.MARINE...
ISSUED AT 328 AM EDT WED MAY 30 2012
NORTHWEST WINDS 10 TO 20 KNOTS WILL RESULT IN 1 TO 3 FOOT WAVES
TODAY.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT WED MAY 30 2012
RAIN IS EXPECTED THURSDAY AFTERNOON THROUGH FRIDAY. A HALF TO AN
INCH OF PCPN IS POSSIBLE SOUTH OF I-96. THIS WILL LIKELY RESULT IN
MINOR RISES ON AREA RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FROST ADVISORY FROM 2 AM TO 8 AM EDT THURSDAY FOR MIZ038>040-
044>046.
LM...NONE.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...93
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
150 AM EDT WED MAY 30 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 432 PM EDT TUE MAY 29 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM NRN
ONTARIO INTO THE UPPER GREAT LAKES. VORT MAX TRACKING ACROSS LAKE
SUPERIOR COMBINED WITH DAYTIME HEATING HAS RESULTED IN SCT -SHRA
ACROSS UPPER MI THIS AFTN. WITH LOW FREEZING LEVELS (5700FT MSL ON
12Z KINL SOUNDING) MORE VIGOROUS CONVECTION HAS PROBABLY BEEN
PRODUCING PEA SIZE HAIL. SPOTTER REPORTED PEA SIZE HAIL AROUND
WAKEFIELD EARLIER IN THE DAY. A FEW LIGHTNING STRIKES HAVE BEEN
DETECTED ACROSS UPPER MI THIS AFTN.
AS VORT MAX SHIFTS E THIS EVENING AND DAYTIME HEATING IS LOST...THE
DIURNALLY DRIVEN -SHRA WILL DISSIPATE. HOWEVER...COOL CYCLONIC FLOW
ALONG WITH SFC TROF PASSING THRU THE AREA SHOULD RESULT IN SOME
-RA/-SHRA THRU THE NIGHT GIVEN CURRENT UPSTREAM RADAR RETURNS N AND
NW OF LAKE SUPERIOR. WITH 850MB TEMPS FALLING TO AROUND -3C MAY SEE
A LITTLE LAKE ENHANCEMENT IN THE UPSLOPE AREAS NEAR LAKE SUPERIOR.
ALSO...GIVEN THE SUBZERO C 850MB TEMPS AND 1000-850MB THICKNESS
FALLING JUST UNDER 1305M...NOT OUT OF THE QUESTION THAT THERE COULD
BE A LITTLE FROZEN PCPN AT TIMES OVER THE HIGH TERRAIN (IT WAS
SNOWING AT CYPL THIS MORNING).
TEMPS WED WILL BE WELL BLO NORMAL WITH 850MB THERMAL TROF PASSING
ACROSS THE AREA DURING THE FIRST HALF OF THE DAY. WITH THE 850MB
TROF OVER THE AREA...EXPECT ABUNDANT CLOUD COVER THRU THE MORNING
HRS. ALSO...SOME LIGHT -RA/-SHRA WILL PROBABLY LINGER NEAR LAKE
SUPERIOR IN THE MORNING. CLEARING WILL THEN BEGIN IN THE AFTN FROM
NW TO SE AS WAA STARTS TO GET UNDERWAY AND LOW-LEVEL FLOW BECOMES
ANTICYCLONIC. MOST AREAS SHOULD BE SUNNY BY LATE AFTN. TEMPS WILL
NOT GET OUT OF THE MID 40S NEAR LAKE SUPERIOR E OF KMQT UNDER CHILLY
AIR MASS AND GRADIENT FLOW ACROSS THE LAKE. LOW/MID 50S WILL BE THE
RULE ELSEWHERE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 432 PM EDT TUE MAY 29 2012
HIGH PRESSURE WILL BE OVER THE CWA ON WED NIGHT. NNE WINDS SHOULD
DIMINISH/DECOUPLE OVERNIGHT AND WITH PWATS AROUND 40 PERCENT OF
NORMAL...SHOULD LEAD TO A COLD NIGHT ACROSS MUCH OF THE CWA. HIGHER
RES MODELS TRYING TO KEEP LINGERING NW WINDS UP OVER THE ERN
CWA...WHICH MAY LIMIT THE COOLING IN THE MORE OPEN LOCATIONS.
WIDESPREAD FROST IS LIKELY OVER THE INTERIOR WEST...WHERE LOWS WILL
BE 28-31...WITH PATCHY/AREAS OF FROST ELSEWHERE AWAY FROM THE GREAT
LKS SHORELINE. MORE THAN LIKELY WILL NEED FROST ADVISORY OVER MUCH
OF THE CWA WED NIGHT AND POTENTIALLY A FREEZE WARNING OVER THE
INTERIOR WEST. CURRENT FORECAST DOESN/T QUITE REACH A HARD FREEZE
CRITERIA...28 DEGREES FOR 3HRS...SO WILL NOT ISSUE A WATCH.
WITH HIGH PRESSURE OVERHEAD AND DRIFTING SE ON THURS...EXPECT A
NICE DAY ACROSS UPPER MI WITH LK BREEZES AND DIURNAL CU THE MAIN
CONCERNS. MOISTURE SLIGHTLY LIMITED...BUT MAY BE ENOUGH FORCING
FROM LK BREEZES AND DIURNAL HEATING TO PRODUCE SOME CLOUDS ALONG THE
LK BREEZES. EXPECT LK BREEZES TO DEVELOP ALONG LK SUPERIOR/MICHIGAN
DURING THE EARLY AFTN...AND LEAD TO COOLING TEMPERATURES NEAR THE
GREAT LKS. BUT WITH THE SUN...SHOULD STILL SEE A QUICK WARM-UP FROM
THE FROSTY TEMPS TO START THE DAY. MIXING TO H800 WOULD YIELD HIGHS
IN THE MID 60S OVER THE INTERIOR LOCATIONS NOT INFLUENCED BY LK
BREEZES. FINALLY...COULD BE SOME HIGH CLOUDS BRUSHING THE WI BORDER
DURING THE AFTN AND ASSOCIATED WITH THE SYSTEM DROPPING THROUGH THE
UPPER/CNTRL MISS VALLEY. THIS SYSTEM WILL BE THE NEXT CONCERN FOR
THE CWA HEADING INTO FRI.
SHORTWAVE ROUNDING THE BASE OF THE TROUGH ON THURS NIGHT WILL HELP
SHARPEN THE TROUGH AND PUSH THE LOW FROM THE OHIO RIVER VALLEY AT
00Z FRI...NNE TO NEAR THE MACKINAC STRAITS AT 00Z SAT. SOME
DIFFERENCES IN THE INTENSITY AND LOCATION OF THE LOW...WITH 12Z GFS
THE STRONGEST AND THE MIDDLE GROUND BETWEEN THE FARTHER N 00Z ECMWF
AND THE WEAKER/SE TRACK OF THE 12Z NAM. PREFER A GENERAL
CONCENSUS OF THE 12Z GFS/GEM AND 00Z ECMWF...WHICH LOOKS MORE LIKE
SOMETHING THAT WOULD BE SEEN IN LATE WINTER OR EARLY SPRING. DUE
TO THE MORE ROBUST AND NORTHERN TRENDS IN THE MODELS OVER
THE LAST DAY...PREVIOUS SHIFT TRENDED IN THE RIGHT DIRECTION ON
CLOUD/POPS. HAVE FOLLOWED SUIT AND BUMPED POPS UP TO LIKELY OVER THE
ERN HALF OF THE CWA ON FRI...AS THE BEST H850-700 WAA PUSHES NNE
THROUGH THE ERN CWA.
FOR THE EXTENDED /FRI NIGHT THROUGH NEXT TUESDAY/...
THE FIRST PART OF THE EXTENDED WILL LARGELY DEPEND ON THE EVOLUTION
OF THE UPPER TROUGH ROTATING THROUGH THE GREAT LKS AND OHIO RIVER
VALLEY. MODELS STILL IN SOME DISAGREEMENT IN THE HANDLING OF THIS
TROUGH...BUT ALL INDICATE THE TROUGH LIFTING NE ON FRI NIGHT AND
INTO SAT. THIS SHOULD LEAD TO SCATTERED SHOWERS DIMINISHING FROM SW
TO NE AS THE TROUGH LIFTS TO THE NE INTO CANADA. THESE TIMING
DIFFERENCES CONTINUE INTO THE BEGINNING OF NEXT WEEK. GENERAL IDEA
OF WEAK HIGH PRESSURE RIDGE LEADING TO DRY WEATHER FOR 12-18HRS
BEHIND THE LOW BEFORE NEXT WAVE APPROACHES THE AREA...LIKELY ON SAT
NIGHT INTO SUN. THE NEXT WAVE...ASSOCIATED WITH WAA ALOFT AND WARM
FRONT STRETCHING SE FROM LOW CENTERED IN THE CANADIAN PRAIRIES WILL
PUSH ACROSS THE AREA SUN NIGHT INTO MON. BEHIND THE FRONT...EXPECT
TEMPS TO TREND BACK TO OR SLIGHTLY ABOVE NORMAL BY TUES AS HIGH
PRESSURE MOVES OVERHEAD AND UPPER RIDGE BEGINS TO DEVELOP OVER THE
NRN/CNTRL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 147 AM EDT WED MAY 30 2012
MVFR CIGS WILL CONTINUE AT ALL TAF SITES OVERNIGHT DUE TO UPSLOPE
FLOW AND SOME LAKE ENHANCEMENT WITH THE MOISTURE OFF THE LAKE AND
COLD TEMPERATURES ALOFT. NOT OUT OF THE QUESTION THAT IFR CIGS COULD
AFFECT KIWD/KSAW THROUGH THE NIGHT. BELIEVE THAT PERSISTENT IFR CIGS
ARE UNLIKELY THOUGH AS CONVERGENCE AND LAKE ENHANCEMENT WILL ONLY BE
TEMPORARY. IMPROVEMENT TO VFR CONDITIONS EXPECTED WED AFTERNOON AS
850MB THERMAL TROF SLIPS TO THE E AND LOW-LEVEL WINDS BECOME
INCREASINGLY ANTICYCLONIC. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT TUE MAY 29 2012
WITH COLD FRONT DROPPING ACROSS LAKE SUPERIOR TONIGHT...WESTERLY
WINDS GUSTING TO 20-25KT WILL SHIFT NORTHERLY. WINDS WILL THEN BEGIN
TO DIMINISH FROM W TO E WED AND ESPECIALLY WED NIGHT AS HIGH PRES
BUILDS INTO THE UPPER LAKES. BY LATE WED NIGHT...WINDS WILL BE UNDER
15KT. WINDS WILL REMAIN MOSTLY UNDER 15KT THRU THU AND INTO FRI
AFTN. WINDS MAY INCREASE A LITTLE LATER FRI INTO SAT OVER EASTERN
LAKE SUPERIOR AS LOW PRES MOVES NE THRU THE CNTRL GREAT LAKES
REGION. OTHERWISE...WINDS WILL GENERALLY REMAIN ON THE LIGHT SIDE
INTO THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...07/JLA
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1156 AM CDT WED MAY 30 2012
.UPDATE...
ISSUED AT 936 AM CDT WED MAY 30 2012
UPDATED THE GRIDS TO REFLECT THE LATEST RADAR AND SATELLITE
TRENDS AS AN AREA OF RAIN SHOWERS CONTINUES MOVING OUT OF THE SERN
CWA THIS MORNING.
KANOFSKY
&&
.SHORT TERM...
ISSUED AT 300 AM CDT WED MAY 30 2012
(TODAY AND TONIGHT)
THUNDERSTORMS CURRENTLY OVER CENTRAL MO HAVE DEVELOPED IN AXIS OF
DECENT 925-850MB MOISTURE CONVERGENCE AHEAD OF A WEAK VORT MAX NOW
ENTERING NORTHWEST MISSOURI. RUC SHOWS THESE FEATURES MOVING EAST
EARLY THIS MORNING AND GOING FORECAST WHICH BRINGS SCT SHRA/TSRA
EASTWARD INTO THE ST. LOUIS METRO EARLY THROUGH 12-15Z STILL LOOKS
GOOD. THEREAFTER...AREA WILL LIE UNDER SUBSIDENCE BEHIND THE WEAK
VORT MAX THROUGH MID AFTERNOON...THOUGH WILL LEAVE A SLIGHT CHANCE
OF THUNDERSTORMS IN OVER THE EASTERN OZARKS WHERE ATMOSPHERE WILL
REMAIN THE MOST UNSTABLE THROUGH THE DAY.
MUCH BETTER CHANCE FOR RAIN WILL ARRIVE TONIGHT AS TROUGH DIGS
SOUTHEASTWARD OUT OF CANADA INTO THE CENTRAL PLAINS. LOW LEVEL JET
WILL INCREASE TONIGHT TRANSPORTING 1.5 INCHES PWATS AND INDUCING
WIDESPREAD LOW LEVEL MOISTURE CONVERGENCE UNDER INCREASING LARGE
SCALE MID LEVEL ASCENT. HAVE LIKELY POPS SPREADING FROM WEST TO
EAST LATE THIS EVENING AND OVERNIGHT.
USED MOS TEMPS TODAY AND TONIGHT WHICH ARE IN GOOD AGREEMENT AND
SEEM REASONABLE.
BRITT
&&
.LONG TERM...
ISSUED AT 414 AM CDT WED MAY 30 2012
(THURSDAY THROUGH TUESDAY)
MODELS ARE NOW MORE PROGRESSIVE WITH THE STORM SYSTEM MOVING EWD
THROUGH OUR AREA THU AND THU NGT. THE FOCUS OF MOST OF THE
CONVECTION THU MRNG MAY BE ACROSS NERN MO AND W CNTRL IL WHERE
850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE WILL BE
MAXIMIZED ON THE NOSE OF A S-SWLY LOW LEVEL JET AHEAD OF AN
APPROACHING 850 MB LOW. THE MODELS WERE FAIRLY CONSISTENT IN
DROPPING AN UPPER LEVEL TROUGH SEWD THROUGH THE NRN PLAINS ON THU
WHILE A STRONG SRN STREAM SHORTWAVE AND ASSOCIATED SFC LOW MOVE
NEWD THROUGH SERN MO AND SRN IL. THERE IS SOME VARIATION WITH THE
EXACT TRACK OF THE SFC LOW WITH THE ECMWF MODEL THE FURTHER MOST S
AND THE GFS THE FURTHER MOST N. EVEN THE MOST NRN TRACK HAS THE
SFC LOW MOVING THROUGH OR JUST S OF STL. THE MOST WIDESPREAD AND
HEAVIEST RAIN SHOULD FALL LEFT OF THE TRACK OF THE SFC LOW. HIGH
TEMPERATURES ON THU WILL BE COOLER THAN PERSISTENCE AND BELOW
NORMAL DUE TO WIDESPREAD CLOUDS AND PRECIPITATION ALONG WITH LOW
LEVEL CAA BEGINNING THU AFTN. THE PRECIPITATION WILL BEGIN TO
TAPER OFF FROM NW TO SE ALREADY THU NGT AS THE SFC LOW MOVES NEWD
INTO THE OHIO VALLEY REGION BY 12Z FRI WITH THE MID LEVEL LOW OVER
NRN IL. TEMPERATURES WILL BE QUITE COOL THU NGT WITH THE MODELS
DROPPING THE 4 DEGREE C 850 MB ISOTHERM SWD THROUGH MUCH OF OUR
AREA BY 12Z FRI. THERE MAY BE SOME LIGHT PATCHY RAIN MAINLY ACROSS
W CNTRL IL ON FRI...BUT MOST OF THE PRECIPITATION SHOULD BE E-NE
OF OUR AREA ON FRI AS A SFC RIDGE BUILDS E-SEWD INTO SRN MO. BELOW
NORMAL TEMPERATURES WILL CONTINUE ON FRI AND FRI NGT. A WEAK NW
FLOW SHORTWAVE MAY BRING LIGHT SHOWERS TO PORTIONS OF NERN AND
CNTRL MO AS WELL AS W CNTRL IL LATE FRI NGT AND SAT MRNG. THE NAM
MODEL ALSO DEPICTS LOW-MID LEVEL WAA ACROSS THE AREA ASSOCIATED
WITH A SWLY LOW LEVEL JET AND AHEAD OF THE SHORTWAVE TROUGH.
TEMPERATURES WILL MODERATE THIS WEEKEND AS THE UPPER LEVEL HEIGHTS
RISE BEHIND THE UPPER LEVEL TROUGH MOVING EWD INTO THE ERN US. THE
ECMWF MODEL DEVELOPS MORE PRECIPITATION SUN NGT AND MON AS ANOTHER
NW FLOW SHORTWAVE DROPS SEWD THROUGH OUR AREA. THE GFS MODEL ALSO
HAS CONVECTION OVER OUR AREA LATE SUN NGT THROUGH TUE BUT IS
APPEARS TO BE SUFFERING FROM FEEDBACK PROBLEMS CAUSING THE
SHORTWAVE TO AMPLIFY TOO MUCH AND LEADING TO TOO MUCH QPF. FOR
THIS REASON WILL FOLLOW THE ECMWF SOLUTION FOR THIS TIME PERIOD
OVER THE GFS MODEL. ABOVE NORMAL TEMPERATURES MAY RETURN TO OUR
AREA MON AND TUE AS AN UPPER LEVEL RIDGE BUILDS OVER THE PLAINS.
GKS
&&
.AVIATION...
ISSUED AT 1149 AM CDT WED MAY 30 2012
VFR CONDITIONS ARE EXPECTED FOR THE REST OF THE AFTERNOON AND MOST
OF THE EVENING BEFORE A BROAD AREA OF SHOWERS AND THUNDERSTORMS
DEVELOPS IN RESPONSE TO AN APPROACHING SHORTWAVE TROF. SHRA/TSRA
CHCS INCREASE AFTER 06Z WITH PCPN SPREADING FROM WEST TO EAST WITH
THE APPROACHING SHORTWAVE. MVFR TO IFR CONDITIONS ARE EXPECTED
WITH LITTLE IMPROVEMENT IN CIGS EVEN AFTER THE RAIN ENDS DUE TO
CYCLONIC FLOW ALOFT.
SPECIFICS FOR KSTL...VFR CONDITIONS ARE EXPECTED FOR THE REST OF
THE AFTERNOON AND MOST OF THE EVENING BEFORE A BROAD AREA OF
SHOWERS AND THUNDERSTORMS DEVELOPS IN RESPONSE TO AN APPROACHING
SHORTWAVE TROF. SHRA/TSRA WILL BE SPREADING FROM WEST TO EAST WITH
THE BEST PCPN CHCS AT METRO AREA TAF SITES AFTER APPROXIMATELY
09Z. MVFR TO IFR CONDITIONS ARE EXPECTED WITH LITTLE IMPROVEMENT
IN CIGS EVEN AFTER THE RAIN ENDS DUE TO CYCLONIC FLOW ALOFT.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
938 AM CDT WED MAY 30 2012
.UPDATE...
ISSUED AT 936 AM CDT WED MAY 30 2012
UPDATED THE GRIDS TO REFLECT THE LATEST RADAR AND SATELLITE
TRENDS AS AN AREA OF RAIN SHOWERS CONTINUES MOVING OUT OF THE SERN
CWA THIS MORNING.
KANOFSKY
&&
.SHORT TERM...
ISSUED AT 300 AM CDT WED MAY 30 2012
(TODAY AND TONIGHT)
THUNDERSTORMS CURRENTLY OVER CENTRAL MO HAVE DEVELOPED IN AXIS OF
DECENT 925-850MB MOISTURE CONVERGENCE AHEAD OF A WEAK VORT MAX NOW
ENTERING NORTHWEST MISSOURI. RUC SHOWS THESE FEATURES MOVING EAST
EARLY THIS MORNING AND GOING FORECAST WHICH BRINGS SCT SHRA/TSRA
EASTWARD INTO THE ST. LOUIS METRO EARLY THROUGH 12-15Z STILL LOOKS
GOOD. THEREAFTER...AREA WILL LIE UNDER SUBSIDENCE BEHIND THE WEAK
VORT MAX THROUGH MID AFTERNOON...THOUGH WILL LEAVE A SLIGHT CHANCE
OF THUNDERSTORMS IN OVER THE EASTERN OZARKS WHERE ATMOSPHERE WILL
REMAIN THE MOST UNSTABLE THROUGH THE DAY.
MUCH BETTER CHANCE FOR RAIN WILL ARRIVE TONIGHT AS TROUGH DIGS
SOUTHEASTWARD OUT OF CANADA INTO THE CENTRAL PLAINS. LOW LEVEL JET
WILL INCREASE TONIGHT TRANSPORTING 1.5 INCHES PWATS AND INDUCING
WIDESPREAD LOW LEVEL MOISTURE CONVERGENCE UNDER INCREASING LARGE
SCALE MID LEVEL ASCENT. HAVE LIKELY POPS SPREADING FROM WEST TO
EAST LATE THIS EVENING AND OVERNIGHT.
USED MOS TEMPS TODAY AND TONIGHT WHICH ARE IN GOOD AGREEMENT AND
SEEM REASONABLE.
BRITT
&&
.LONG TERM...
ISSUED AT 414 AM CDT WED MAY 30 2012
(THURSDAY THROUGH TUESDAY)
MODELS ARE NOW MORE PROGRESSIVE WITH THE STORM SYSTEM MOVING EWD
THROUGH OUR AREA THU AND THU NGT. THE FOCUS OF MOST OF THE
CONVECTION THU MRNG MAY BE ACROSS NERN MO AND W CNTRL IL WHERE
850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE WILL BE
MAXIMIZED ON THE NOSE OF A S-SWLY LOW LEVEL JET AHEAD OF AN
APPROACHING 850 MB LOW. THE MODELS WERE FAIRLY CONSISTENT IN
DROPPING AN UPPER LEVEL TROUGH SEWD THROUGH THE NRN PLAINS ON THU
WHILE A STRONG SRN STREAM SHORTWAVE AND ASSOCIATED SFC LOW MOVE
NEWD THROUGH SERN MO AND SRN IL. THERE IS SOME VARIATION WITH THE
EXACT TRACK OF THE SFC LOW WITH THE ECMWF MODEL THE FURTHER MOST S
AND THE GFS THE FURTHER MOST N. EVEN THE MOST NRN TRACK HAS THE
SFC LOW MOVING THROUGH OR JUST S OF STL. THE MOST WIDESPREAD AND
HEAVIEST RAIN SHOULD FALL LEFT OF THE TRACK OF THE SFC LOW. HIGH
TEMPERATURES ON THU WILL BE COOLER THAN PERSISTENCE AND BELOW
NORMAL DUE TO WIDESPREAD CLOUDS AND PRECIPITATION ALONG WITH LOW
LEVEL CAA BEGINNING THU AFTN. THE PRECIPITATION WILL BEGIN TO
TAPER OFF FROM NW TO SE ALREADY THU NGT AS THE SFC LOW MOVES NEWD
INTO THE OHIO VALLEY REGION BY 12Z FRI WITH THE MID LEVEL LOW OVER
NRN IL. TEMPERATURES WILL BE QUITE COOL THU NGT WITH THE MODELS
DROPPING THE 4 DEGREE C 850 MB ISOTHERM SWD THROUGH MUCH OF OUR
AREA BY 12Z FRI. THERE MAY BE SOME LIGHT PATCHY RAIN MAINLY ACROSS
W CNTRL IL ON FRI...BUT MOST OF THE PRECIPITATION SHOULD BE E-NE
OF OUR AREA ON FRI AS A SFC RIDGE BUILDS E-SEWD INTO SRN MO. BELOW
NORMAL TEMPERATURES WILL CONTINUE ON FRI AND FRI NGT. A WEAK NW
FLOW SHORTWAVE MAY BRING LIGHT SHOWERS TO PORTIONS OF NERN AND
CNTRL MO AS WELL AS W CNTRL IL LATE FRI NGT AND SAT MRNG. THE NAM
MODEL ALSO DEPICTS LOW-MID LEVEL WAA ACROSS THE AREA ASSOCIATED
WITH A SWLY LOW LEVEL JET AND AHEAD OF THE SHORTWAVE TROUGH.
TEMPERATURES WILL MODERATE THIS WEEKEND AS THE UPPER LEVEL HEIGHTS
RISE BEHIND THE UPPER LEVEL TROUGH MOVING EWD INTO THE ERN US. THE
ECMWF MODEL DEVELOPS MORE PRECIPITATION SUN NGT AND MON AS ANOTHER
NW FLOW SHORTWAVE DROPS SEWD THROUGH OUR AREA. THE GFS MODEL ALSO
HAS CONVECTION OVER OUR AREA LATE SUN NGT THROUGH TUE BUT IS
APPEARS TO BE SUFFERING FROM FEEDBACK PROBLEMS CAUSING THE
SHORTWAVE TO AMPLIFY TOO MUCH AND LEADING TO TOO MUCH QPF. FOR
THIS REASON WILL FOLLOW THE ECMWF SOLUTION FOR THIS TIME PERIOD
OVER THE GFS MODEL. ABOVE NORMAL TEMPERATURES MAY RETURN TO OUR
AREA MON AND TUE AS AN UPPER LEVEL RIDGE BUILDS OVER THE PLAINS.
GKS
&&
.AVIATION...
ISSUED AT 547 AM CDT WED MAY 30 2012
SHOWERS AND ISOLATED THUNDERSTORMS HAVE MOVED INTO EAST CENTRAL MO
AND ARE EXPECTED TO AFFECT THE ST. LOUIS METRO TAF SITES THROUGH
14Z. THIS AREA OF RAIN WILL THEN MOVE OFF AND THE TAF SITES SHOULD
REMAIN DRY AND VFR UNTIL AFTER 06Z...WITH THE BEST CHANCE FOR
ADDITIONAL -SHRA/-TSRA REMAINING OVER SOUTHERN MISSOURI.
WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS ARE EXPECTED TO
SPREAD FROM WEST TO EAST ACROSS THE AREA AFTER 06Z TONIGHT. INITIAL
VFR CONDITIONS WITH THE ONSET OF RAIN WILL LOWER...WITH IFR CIGS
AND VSBYS POSSIBLE AFTER 12Z TOMORROW.
SPECIFICS FOR KSTL...STILL EXPECT AREA OF -SHRA AND ISOLATED TSRA
TO MOVE INTO THE TERMINAL BEFORE MOVING OFF TO THE EAST AROUND
13Z. AS MENTIONED ABOVE...THEN EXPECT DRY AND VFR CONDITIONS UNTIL
AFTER 12Z WHEN CIGS AND VSBYS WILL LOWER TO LOW MVFR OR IFR.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
548 AM CDT WED MAY 30 2012
.SHORT TERM...
ISSUED AT 300 AM CDT WED MAY 30 2012
(TODAY AND TONIGHT)
THUNDERSTORMS CURRENTLY OVER CENTRAL MO HAVE DEVELOPED IN AXIS OF
DECENT 925-850MB MOISTURE CONVERGENCE AHEAD OF A WEAK VORT MAX NOW
ENTERING NORTHWEST MISSOURI. RUC SHOWS THESE FEATURES MOVING EAST
EARLY THIS MORNING AND GOING FORECAST WHICH BRINGS SCT SHRA/TSRA
EASTWARD INTO THE ST. LOUIS METRO EARLY THROUGH 12-15Z STILL LOOKS
GOOD. THEREAFTER...AREA WILL LIE UNDER SUBSIDENCE BEHIND THE WEAK
VORT MAX THROUGH MID AFTERNOON...THOUGH WILL LEAVE A SLIGHT CHANCE
OF THUNDERSTORMS IN OVER THE EASTERN OZARKS WHERE ATMOSPHERE WILL
REMAIN THE MOST UNSTABLE THROUGH THE DAY.
MUCH BETTER CHANCE FOR RAIN WILL ARRIVE TONIGHT AS TROUGH DIGS
SOUTHEASTWARD OUT OF CANADA INTO THE CENTRAL PLAINS. LOW LEVEL JET
WILL INCREASE TONIGHT TRANSPORTING 1.5 INCHES PWATS AND INDUCING
WIDESPREAD LOW LEVEL MOISTURE CONVERGENCE UNDER INCREASING LARGE
SCALE MID LEVEL ASCENT. HAVE LIKELY POPS SPREADING FROM WEST TO
EAST LATE THIS EVENING AND OVERNIGHT.
USED MOS TEMPS TODAY AND TONIGHT WHICH ARE IN GOOD AGREEMENT AND
SEEM REASONABLE.
BRITT
&&
.LONG TERM...
ISSUED AT 414 AM CDT WED MAY 30 2012
(THURSDAY THROUGH TUESDAY)
MODELS ARE NOW MORE PROGRESSIVE WITH THE STORM SYSTEM MOVING EWD
THROUGH OUR AREA THU AND THU NGT. THE FOCUS OF MOST OF THE
CONVECTION THU MRNG MAY BE ACROSS NERN MO AND W CNTRL IL WHERE
850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE WILL BE
MAXIMIZED ON THE NOSE OF A S-SWLY LOW LEVEL JET AHEAD OF AN
APPROACHING 850 MB LOW. THE MODELS WERE FAIRLY CONSISTENT IN
DROPPING AN UPPER LEVEL TROUGH SEWD THROUGH THE NRN PLAINS ON THU
WHILE A STRONG SRN STREAM SHORTWAVE AND ASSOCIATED SFC LOW MOVE
NEWD THROUGH SERN MO AND SRN IL. THERE IS SOME VARIATION WITH THE
EXACT TRACK OF THE SFC LOW WITH THE ECMWF MODEL THE FURTHER MOST S
AND THE GFS THE FURTHER MOST N. EVEN THE MOST NRN TRACK HAS THE
SFC LOW MOVING THROUGH OR JUST S OF STL. THE MOST WIDESPREAD AND
HEAVIEST RAIN SHOULD FALL LEFT OF THE TRACK OF THE SFC LOW. HIGH
TEMPERATURES ON THU WILL BE COOLER THAN PERSISTENCE AND BELOW
NORMAL DUE TO WIDESPREAD CLOUDS AND PRECIPITATION ALONG WITH LOW
LEVEL CAA BEGINNING THU AFTN. THE PRECIPITATION WILL BEGIN TO
TAPER OFF FROM NW TO SE ALREADY THU NGT AS THE SFC LOW MOVES NEWD
INTO THE OHIO VALLEY REGION BY 12Z FRI WITH THE MID LEVEL LOW OVER
NRN IL. TEMPERATURES WILL BE QUITE COOL THU NGT WITH THE MODELS
DROPPING THE 4 DEGREE C 850 MB ISOTHERM SWD THROUGH MUCH OF OUR
AREA BY 12Z FRI. THERE MAY BE SOME LIGHT PATCHY RAIN MAINLY ACROSS
W CNTRL IL ON FRI...BUT MOST OF THE PRECIPITATION SHOULD BE E-NE
OF OUR AREA ON FRI AS A SFC RIDGE BUILDS E-SEWD INTO SRN MO. BELOW
NORMAL TEMPERATURES WILL CONTINUE ON FRI AND FRI NGT. A WEAK NW
FLOW SHORTWAVE MAY BRING LIGHT SHOWERS TO PORTIONS OF NERN AND
CNTRL MO AS WELL AS W CNTRL IL LATE FRI NGT AND SAT MRNG. THE NAM
MODEL ALSO DEPICTS LOW-MID LEVEL WAA ACROSS THE AREA ASSOCIATED
WITH A SWLY LOW LEVEL JET AND AHEAD OF THE SHORTWAVE TROUGH.
TEMPERATURES WILL MODERATE THIS WEEKEND AS THE UPPER LEVEL HEIGHTS
RISE BEHIND THE UPPER LEVEL TROUGH MOVING EWD INTO THE ERN US. THE
ECMWF MODEL DEVELOPS MORE PRECIPITATION SUN NGT AND MON AS ANOTHER
NW FLOW SHORTWAVE DROPS SEWD THROUGH OUR AREA. THE GFS MODEL ALSO
HAS CONVECTION OVER OUR AREA LATE SUN NGT THROUGH TUE BUT IS
APPEARS TO BE SUFFERING FROM FEEDBACK PROBLEMS CAUSING THE
SHORTWAVE TO AMPLIFY TOO MUCH AND LEADING TO TOO MUCH QPF. FOR
THIS REASON WILL FOLLOW THE ECMWF SOLUTION FOR THIS TIME PERIOD
OVER THE GFS MODEL. ABOVE NORMAL TEMPERATURES MAY RETURN TO OUR
AREA MON AND TUE AS AN UPPER LEVEL RIDGE BUILDS OVER THE PLAINS.
GKS
&&
.AVIATION...
ISSUED AT 547 AM CDT WED MAY 30 2012
SHOWERS AND ISOLATED THUNDERSTORMS HAVE MOVED INTO EAST CENTRAL MO
AND ARE EXPECTED TO AFFECT THE ST. LOUIS METRO TAF SITES THROUGH
14Z. THIS AREA OF RAIN WILL THEN MOVE OFF AND THE TAF SITES SHOULD
REMAIN DRY AND VFR UNTIL AFTER 06Z...WITH THE BEST CHANCE FOR
ADDITIONAL -SHRA/-TSRA REMAINING OVER SOUTHERN MISSOURI.
WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS ARE EXPECTED TO
SPREAD FROM WEST TO EAST ACROSS THE AREA AFTER 06Z TONIGHT. INITIAL
VFR CONDITIONS WITH THE ONSET OF RAIN WILL LOWER...WITH IFR CIGS
AND VSBYS POSSIBLE AFTER 12Z TOMORROW.
SPECIFICS FOR KSTL...STILL EXPECT AREA OF -SHRA AND ISOLATED TSRA
TO MOVE INTO THE TERMINAL BEFORE MOVING OFF TO THE EAST AROUND
13Z. AS MENTIONED ABOVE...THEN EXPECT DRY AND VFR CONDITIONS UNTIL
AFTER 12Z WHEN CIGS AND VSBYS WILL LOWER TO LOW MVFR OR IFR.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
425 AM CDT WED MAY 30 2012
.SHORT TERM...
ISSUED AT 300 AM CDT WED MAY 30 2012
(TODAY AND TONIGHT)
THUNDERSTORMS CURRENTLY OVER CENTRAL MO HAVE DEVELOPED IN AXIS OF
DECENT 925-850MB MOISTURE CONVERGENCE AHEAD OF A WEAK VORT MAX NOW
ENTERING NORTHWEST MISSOURI. RUC SHOWS THESE FEATURES MOVING EAST
EARLY THIS MORNING AND GOING FORECAST WHICH BRINGS SCT SHRA/TSRA
EASTWARD INTO THE ST. LOUIS METRO EARLY THROUGH 12-15Z STILL LOOKS
GOOD. THEREAFTER...AREA WILL LIE UNDER SUBSIDENCE BEHIND THE WEAK
VORT MAX THROUGH MID AFTERNOON...THOUGH WILL LEAVE A SLIGHT CHANCE
OF THUNDERSTORMS IN OVER THE EASTERN OZARKS WHERE ATMOSPHERE WILL
REMAIN THE MOST UNSTABLE THROUGH THE DAY.
MUCH BETTER CHANCE FOR RAIN WILL ARRIVE TONIGHT AS TROUGH DIGS
SOUTHEASTWARD OUT OF CANADA INTO THE CENTRAL PLAINS. LOW LEVEL JET
WILL INCREASE TONIGHT TRANSPORTING 1.5 INCHES PWATS AND INDUCING
WIDESPREAD LOW LEVEL MOISTURE CONVERGENCE UNDER INCREASING LARGE
SCALE MID LEVEL ASCENT. HAVE LIKELY POPS SPREADING FROM WEST TO
EAST LATE THIS EVENING AND OVERNIGHT.
USED MOS TEMPS TODAY AND TONIGHT WHICH ARE IN GOOD AGREEMENT AND
SEEM REASONABLE.
BRITT
&&
.LONG TERM...
ISSUED AT 414 AM CDT WED MAY 30 2012
(THURSDAY THROUGH TUESDAY)
MODELS ARE NOW MORE PROGRESSIVE WITH THE STORM SYSTEM MOVING EWD
THROUGH OUR AREA THU AND THU NGT. THE FOCUS OF MOST OF THE
CONVECTION THU MRNG MAY BE ACROSS NERN MO AND W CNTRL IL WHERE
850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE WILL BE
MAXIMIZED ON THE NOSE OF A S-SWLY LOW LEVEL JET AHEAD OF AN
APPROACHING 850 MB LOW. THE MODELS WERE FAIRLY CONSISTENT IN
DROPPING AN UPPER LEVEL TROUGH SEWD THROUGH THE NRN PLAINS ON THU
WHILE A STRONG SRN STREAM SHORTWAVE AND ASSOCIATED SFC LOW MOVE
NEWD THROUGH SERN MO AND SRN IL. THERE IS SOME VARIATION WITH THE
EXACT TRACK OF THE SFC LOW WITH THE ECMWF MODEL THE FURTHER MOST S
AND THE GFS THE FURTHER MOST N. EVEN THE MOST NRN TRACK HAS THE
SFC LOW MOVING THROUGH OR JUST S OF STL. THE MOST WIDESPREAD AND
HEAVIEST RAIN SHOULD FALL LEFT OF THE TRACK OF THE SFC LOW. HIGH
TEMPERATURES ON THU WILL BE COOLER THAN PERSISTENCE AND BELOW
NORMAL DUE TO WIDESPREAD CLOUDS AND PRECIPITATION ALONG WITH LOW
LEVEL CAA BEGINNING THU AFTN. THE PRECIPITATION WILL BEGIN TO
TAPER OFF FROM NW TO SE ALREADY THU NGT AS THE SFC LOW MOVES NEWD
INTO THE OHIO VALLEY REGION BY 12Z FRI WITH THE MID LEVEL LOW OVER
NRN IL. TEMPERATURES WILL BE QUITE COOL THU NGT WITH THE MODELS
DROPPING THE 4 DEGREE C 850 MB ISOTHERM SWD THROUGH MUCH OF OUR
AREA BY 12Z FRI. THERE MAY BE SOME LIGHT PATCHY RAIN MAINLY ACROSS
W CNTRL IL ON FRI...BUT MOST OF THE PRECIPITATION SHOULD BE E-NE
OF OUR AREA ON FRI AS A SFC RIDGE BUILDS E-SEWD INTO SRN MO. BELOW
NORMAL TEMPERATURES WILL CONTINUE ON FRI AND FRI NGT. A WEAK NW
FLOW SHORTWAVE MAY BRING LIGHT SHOWERS TO PORTIONS OF NERN AND
CNTRL MO AS WELL AS W CNTRL IL LATE FRI NGT AND SAT MRNG. THE NAM
MODEL ALSO DEPICTS LOW-MID LEVEL WAA ACROSS THE AREA ASSOCIATED
WITH A SWLY LOW LEVEL JET AND AHEAD OF THE SHORTWAVE TROUGH.
TEMPERATURES WILL MODERATE THIS WEEKEND AS THE UPPER LEVEL HEIGHTS
RISE BEHIND THE UPPER LEVEL TROUGH MOVING EWD INTO THE ERN US. THE
ECMWF MODEL DEVELOPS MORE PRECIPITATION SUN NGT AND MON AS ANOTHER
NW FLOW SHORTWAVE DROPS SEWD THROUGH OUR AREA. THE GFS MODEL ALSO
HAS CONVECTION OVER OUR AREA LATE SUN NGT THROUGH TUE BUT IS
APPEARS TO BE SUFFERING FROM FEEDBACK PROBLEMS CAUSING THE
SHORTWAVE TO AMPLIFY TOO MUCH AND LEADING TO TOO MUCH QPF. FOR
THIS REASON WILL FOLLOW THE ECMWF SOLUTION FOR THIS TIME PERIOD
OVER THE GFS MODEL. ABOVE NORMAL TEMPERATURES MAY RETURN TO OUR
AREA MON AND TUE AS AN UPPER LEVEL RIDGE BUILDS OVER THE PLAINS.
GKS
&&
.AVIATION...
ISSUED AT 1215 AM CDT WED MAY 30 2012
CONVECTION HAS DEVELOPED IN THE KC METRO AREA AND THIS WAS A KEY
AREA FOR PCPN TO DEVELOP IF IT IS TO AFFECT THE I-70 TERMINALS.
WITH THAT NOW CONFIRMED...HAVE PLACED IN VCTS OR VCSH IN THE TAFS
ALG I-70 FOR LATE TONIGHT AND EARLY WEDNESDAY MORNING. IN THE WAKE
OF CONVECTION EARLY THIS MORNING...A PRETTY DRY ATMOSPHERE BELOW
15KFT WILL EXIST FOR MUCH OF THE REST OF THE VALID TAF PERIOD AS
SFC HI PRES DOMINATES MUCH OF THE REGION. THE SECOND UPPER LEVEL
DISTURBANCE WILL ROLL THRU LATER ON WEDNESDAY NIGHT AND INTO
THURSDAY AND SHOULD CARRY WITH IT NON-VFR CONDITIONS AND
WIDESPREAD PCPN...BUT THE TIMING OF IT FAVORED BY MOST MODELS WILL
NOT BRING IT IN UNTIL NEAR OR JUST AFTER THE VALID PERIOD ENDS.
SPECIFICS FOR KSTL...VFR CONDITIONS AND LIGHT N SFC WNDS CAN BE
EXPECTED FOR MUCH OF THE VALID PERIOD...WITH SFC WNDS VEERING NE
LATE. HAVE ADDED IN VCSH LATE TONIGHT FOR SCT SHRA BEING ON THE
NRN EDGE OF WHERE WE EXPECT THIS CONVECTION OVER IN KC METRO TO
GO. THE MAIN ROUND OF PCPN WILL HOLD OFF UNTIL LATE WEDNESDAY
NIGHT.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
301 AM CDT WED MAY 30 2012
.SHORT TERM...
ISSUED AT 300 AM CDT WED MAY 30 2012
(TODAY AND TONIGHT)
THUNDERSTORMS CURRENTLY OVER CENTRAL MO HAVE DEVELOPED IN AXIS OF
DECENT 925-850MB MOISTURE CONVERGENCE AHEAD OF A WEAK VORT MAX NOW
ENTERING NORTHWEST MISSOURI. RUC SHOWS THESE FEATURES MOVING EAST
EARLY THIS MORNING AND GOING FORECAST WHICH BRINGS SCT SHRA/TSRA
EASTWARD INTO THE ST. LOUIS METRO EARLY THROUGH 12-15Z STILL LOOKS
GOOD. THEREAFTER...AREA WILL LIE UNDER SUBSIDENCE BEHIND THE WEAK
VORT MAX THROUGH MID AFTERNOON...THOUGH WILL LEAVE A SLIGHT CHANCE
OF THUNDERSTORMS IN OVER THE EASTERN OZARKS WHERE ATMOSPHERE WILL
REMAIN THE MOST UNSTABLE THROUGH THE DAY.
MUCH BETTER CHANCE FOR RAIN WILL ARRIVE TONIGHT AS TROUGH DIGS
SOUTHEASTWARD OUT OF CANADA INTO THE CENTRAL PLAINS. LOW LEVEL JET
WILL INCREASE TONIGHT TRANSPORTING 1.5 INCHES PWATS AND INDUCING
WIDESPREAD LOW LEVEL MOISTURE CONVERGENCE UNDER INCREASING LARGE
SCALE MID LEVEL ASCENT. HAVE LIKELY POPS SPREADING FROM WEST TO
EAST LATE THIS EVENING AND OVERNIGHT.
USED MOS TEMPS TODAY AND TONIGHT WHICH ARE IN GOOD AGREEMENT AND
SEEM REASONABLE.
BRITT
&&
.AVIATION...
ISSUED AT 1215 AM CDT WED MAY 30 2012
CONVECTION HAS DEVELOPED IN THE KC METRO AREA AND THIS WAS A KEY
AREA FOR PCPN TO DEVELOP IF IT IS TO AFFECT THE I-70 TERMINALS.
WITH THAT NOW CONFIRMED...HAVE PLACED IN VCTS OR VCSH IN THE TAFS
ALG I-70 FOR LATE TONIGHT AND EARLY WEDNESDAY MORNING. IN THE WAKE
OF CONVECTION EARLY THIS MORNING...A PRETTY DRY ATMOSPHERE BELOW
15KFT WILL EXIST FOR MUCH OF THE REST OF THE VALID TAF PERIOD AS
SFC HI PRES DOMINATES MUCH OF THE REGION. THE SECOND UPPER LEVEL
DISTURBANCE WILL ROLL THRU LATER ON WEDNESDAY NIGHT AND INTO
THURSDAY AND SHOULD CARRY WITH IT NON-VFR CONDITIONS AND
WIDESPREAD PCPN...BUT THE TIMING OF IT FAVORED BY MOST MODELS WILL
NOT BRING IT IN UNTIL NEAR OR JUST AFTER THE VALID PERIOD ENDS.
SPECIFICS FOR KSTL...VFR CONDITIONS AND LIGHT N SFC WNDS CAN BE
EXPECTED FOR MUCH OF THE VALID PERIOD...WITH SFC WNDS VEERING NE
LATE. HAVE ADDED IN VCSH LATE TONIGHT FOR SCT SHRA BEING ON THE
NRN EDGE OF WHERE WE EXPECT THIS CONVECTION OVER IN KC METRO TO
GO. THE MAIN ROUND OF PCPN WILL HOLD OFF UNTIL LATE WEDNESDAY
NIGHT.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1215 AM CDT WED MAY 30 2012
.UPDATE...
ISSUED AT 1138 PM CDT TUE MAY 29 2012
SCATTERED STORMS HAVE DEVELOPED OVER EASTERN KANSAS AND ARE MOVING
SLOWLY EAST. HAVE UPPPED POPS TO CHANCE TOWARD 12Z ALONG THE I-70
CORRIDOR FOLLOWING THE HRRR/RAP.
ISSUED AT 935 PM CDT TUE MAY 29 2012
00Z NAM IS MOSTLY IN AND IS SHOWING NO PRECIP AT ALL ACROSS THE
ENTIRE CWFA. RAP AND HRRR STILL DEVELOP A CLUSTER OF STORMS AROUND
KANSAS CITY AND MOVE THEM EAST-SOUTHEAST TO NEAR COLUMBIA BY 10Z
AND CONTINUING TO SOUTHWEST OF THE STL METRO AREA BY 12Z. HAVE
MADE SOME MINOR TWEAKS TO POPS AND TEMPS FOR THE REST OF THE
NIGHT...BUT THE GIST IS STILL CHANCE/SLIGHT CHANCE DEVELOPING LATE
WITH LOWS RANGING FROM THE LOW TO MID 50S IN NORTHEAST MISSOURI TO
THE LOW 60S IN SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS...WARMER
IN THE METRO AREA. WILL CONTINUE TO MONITOR AND RE-EVALUATE LATER
TONIGHT WHEN THE GFS COMES IN.
CARNEY
&&
.SHORT TERM...
ISSUED AT 156 PM CDT TUE MAY 29 2012
(TONIGHT)
MDLS CONTINUE TO DEPICT AREA OF ELEVATED CONVECTION MOVING INTO
PORTIONS OF CNTL MO LATE TONIGHT. LATEST GUIDANCE SUGGESTS PRECIP
WILL DEVELOP/MOVE INTO WRN PORTIONS OF THE CWA SHORTLY AFTER
MIDNIGHT. THERE IS SOME ELEVATED INSTABILITY...BUT FORCING IS
SOMEWHAT MINIMAL. HAVE THEREFORE KEPT POPS AT LOW CHANCE.
TRENDED TEMPS TONIGHT TWD THE WARMER GUIDANCE...AT LEAST ACROSS
THE SRN HALF TO TWO-THIRDS OF THE CWA. EVEN WITH A WEAK SECONDARY
CDFNT MOVING INTO THE AREA...BELIEVE CLOUDS MOVING IN WILL HELP
KEEP TEMPS ON THE WARMER SIDE.
TILLY
&&
.LONG TERM...
ISSUED AT 306 PM CDT TUE MAY 29 2012
(WEDNESDAY THROUGH TUESDAY)
MAIN ATTENTION THROUGH FRIDAY IS FOCUSED ON THE SHORT WAVE TROF
MOVING THROUGH THE PACIFIC NW. FOR WEDNESDAY THERE COULD BE SOME LOW
LEVEL WAA/FRONTOGENTECIALY DRIVEN SHRA/TSRA DURING THE MORNING SOUTH
OF INTERSTATE 70 IN MO...OTHERWISE THE REMAINDER OF THE DAY SHOULD
BE MARKED BY SLIGHTLY COOLER TEMPERATURES WITH AN INCREASE IN CLOUDS
DURING THE LATER PART OF THE AFTERNOON AHEAD OF THE NEXT BIG SYSTEM.
THE MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH THE 12Z CYCLE
AND THE GENERAL CONSENSUS IS A MORE PROGRESSIVE SOLUTION WHICH THE
ECMWF HAS BEEN ADVERTISING FOR SEVERAL DAYS. CURRENT INDICATIONS ARE
THE AFOREMENTIONED PAC NW SHORT WAVE WILL DIG INTO THE
NORTHERN/CENTRAL PLAINS ON WEDNESDAY NIGHT AND AMPLIFY...WHILE A
LEAD IMPULSE TRACKS IN THE VICINITY OF THE OK/KS BORDER INTO SW MO
BY 12Z THURS. IN RESPONSE A LARGE REGION OF SIGNIFICANT LARGE SCALE
ASCENT IS FORECAST TO SPREAD INTO THE MS VALLEY WITH A 30-40 KT SLY
LOW LEVEL JET FOCUSING LOW LEVEL MOISTURE TRANSPORT AND LIFT AS
WELL. A LARGE REGION OF SHOWERS AND EMBEDDED ELEVATED THUNDERSTORMS
IS EXPECTED TO RESULT WITH MORE INTENSE CONVECTION ACROSS SOUTHERN
MO AND POINTS SOUTH. THERE ARE STILL SOME UNCERTAINTIES IN THE EXACT
EASTWARD SPREAD OF PRECIPITATION ON WED NIGHT...BUT THE MODEL
CONSENSUS WOULD BE TO AT LEAST THE MS RIVER BY DAYBREAK THURSDAY. THE
SHIELD OF PRECIPITATION SHOULD CONTINUE TO ADVANCE EAST ON THURSDAY
IN ASSOCIATION WITH CONTINUE PROGRESSION AND DIGGING OF THE UPPER
LOW/TROF INTO THE MS VALLEY. THE CLOUDS AND PRECIPITATION SHOULD
INHIBIT MUCH TEMPERATURE REBOUND. THE MAIN AREA OF PRECIPITATION
SHOULD THEN MOVE TO THE EAST INTO THE OH/TN VALLEY REGION ON
THURSDAY NIGHT AS THE DEEPENING YET PROGRESSIVE UPPER TROF
CONTINUES EASTWARD. THE HIGHEST POPS ON THURSDAY NIGHT WILL BE IN
SW AND SOUTH CENTRAL IL...TAPERING SIGNIFICANTLY BACK INTO CENTRAL
MO.
AN UNSEASONABLY COOL DAY LOOKS ON TAP FOR FRIDAY WITH THE UPPER LOW
AND TROF SLIDING EASTWARD AND DEEP CYCLONIC FLOW ACROSS THE AREA. AT
THE LEAST I AM EXPECTING EXTENSIVE STRATUS/STRATOCU...AND
POSSIBLY SOME SPOTTY INSTABILITY SHOWERS OVER THE NE HALF OF THE
CWA. H85 TEMPS OF +3/+5 DURING THE AFTERNOON ARE 2 TO 5 STANDARD
DEVIATIONS BELOW NORMAL...AND SUPPORT THE CURRENT FORECAST OF WELL
BELOW AVERAGE HIGHS FOR THE DAY.
THE BOUT OF COOL WEATHER LOOKS SHORT-LIVED HOWEVER WITH HEIGHTS
ALOFT ON THE RISE SAT-SUN AS THE DEEP UPPER TROF EXITS TO THE ENE
INTO THE WESTERN ATLANTIC. IN FACT...H5 HEIGHTS RISE SOME +240
METERS FROM 12Z SAT THRU 00Z SUN...AND BY MONDAY AFTERNOON THE LOW
LEVEL FLOW IS SSWLY WITH H85 TEMPS OF +20 TO +22. FROM LATE MONDAY
INTO TUESDAY WE WILL HAVE TO KEEP AN EYE ON A SAGGING WEST-EAST
FRONT AND POTENTIAL FOR THUNDERSTORMS.
GLASS
&&
.AVIATION...
ISSUED AT 1215 AM CDT WED MAY 30 2012
CONVECTION HAS DEVELOPED IN THE KC METRO AREA AND THIS WAS A KEY
AREA FOR PCPN TO DEVELOP IF IT IS TO AFFECT THE I-70 TERMINALS.
WITH THAT NOW CONFIRMED...HAVE PLACED IN VCTS OR VCSH IN THE TAFS
ALG I-70 FOR LATE TONIGHT AND EARLY WEDNESDAY MORNING. IN THE WAKE
OF CONVECTION EARLY THIS MORNING...A PRETTY DRY ATMOSPHERE BELOW
15KFT WILL EXIST FOR MUCH OF THE REST OF THE VALID TAF PERIOD AS
SFC HI PRES DOMINATES MUCH OF THE REGION. THE SECOND UPPER LEVEL
DISTURBANCE WILL ROLL THRU LATER ON WEDNESDAY NIGHT AND INTO
THURSDAY AND SHOULD CARRY WITH IT NON-VFR CONDITIONS AND
WIDESPREAD PCPN...BUT THE TIMING OF IT FAVORED BY MOST MODELS WILL
NOT BRING IT IN UNTIL NEAR OR JUST AFTER THE VALID PERIOD ENDS.
SPECIFICS FOR KSTL...VFR CONDITIONS AND LIGHT N SFC WNDS CAN BE
EXPECTED FOR MUCH OF THE VALID PERIOD...WITH SFC WNDS VEERING NE
LATE. HAVE ADDED IN VCSH LATE TONIGHT FOR SCT SHRA BEING ON THE
NRN EDGE OF WHERE WE EXPECT THIS CONVECTION OVER IN KC METRO TO
GO. THE MAIN ROUND OF PCPN WILL HOLD OFF UNTIL LATE WEDNESDAY
NIGHT.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1202 AM CDT WED MAY 30 2012
.UPDATE...
ISSUED AT 1138 PM CDT TUE MAY 29 2012
SCATTERED STORMS HAVE DEVELOPED OVER EASTERN KANSAS AND ARE MOVING
SLOWLY EAST. HAVE UPPPED POPS TO CHANCE TOWARD 12Z ALONG THE I-70
CORRIDOR FOLLOWING THE HRRR/RAP.
ISSUED AT 935 PM CDT TUE MAY 29 2012
00Z NAM IS MOSTLY IN AND IS SHOWING NO PRECIP AT ALL ACROSS THE
ENTIRE CWFA. RAP AND HRRR STILL DEVELOP A CLUSTER OF STORMS AROUND
KANSAS CITY AND MOVE THEM EAST-SOUTHEAST TO NEAR COLUMBIA BY 10Z
AND CONTINUING TO SOUTHWEST OF THE STL METRO AREA BY 12Z. HAVE
MADE SOME MINOR TWEAKS TO POPS AND TEMPS FOR THE REST OF THE
NIGHT...BUT THE GIST IS STILL CHANCE/SLIGHT CHANCE DEVELOPING LATE
WITH LOWS RANGING FROM THE LOW TO MID 50S IN NORTHEAST MISSOURI TO
THE LOW 60S IN SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS...WARMER
IN THE METRO AREA. WILL CONTINUE TO MONITOR AND RE-EVALUATE LATER
TONIGHT WHEN THE GFS COMES IN.
CARNEY
&&
.SHORT TERM...
ISSUED AT 156 PM CDT TUE MAY 29 2012
(TONIGHT)
MDLS CONTINUE TO DEPICT AREA OF ELEVATED CONVECTION MOVING INTO
PORTIONS OF CNTL MO LATE TONIGHT. LATEST GUIDANCE SUGGESTS PRECIP
WILL DEVELOP/MOVE INTO WRN PORTIONS OF THE CWA SHORTLY AFTER
MIDNIGHT. THERE IS SOME ELEVATED INSTABILITY...BUT FORCING IS
SOMEWHAT MINIMAL. HAVE THEREFORE KEPT POPS AT LOW CHANCE.
TRENDED TEMPS TONIGHT TWD THE WARMER GUIDANCE...AT LEAST ACROSS
THE SRN HALF TO TWO-THIRDS OF THE CWA. EVEN WITH A WEAK SECONDARY
CDFNT MOVING INTO THE AREA...BELIEVE CLOUDS MOVING IN WILL HELP
KEEP TEMPS ON THE WARMER SIDE.
TILLY
&&
.LONG TERM...
ISSUED AT 306 PM CDT TUE MAY 29 2012
(WEDNESDAY THROUGH TUESDAY)
MAIN ATTENTION THROUGH FRIDAY IS FOCUSED ON THE SHORT WAVE TROF
MOVING THROUGH THE PACIFIC NW. FOR WEDNESDAY THERE COULD BE SOME LOW
LEVEL WAA/FRONTOGENTECIALY DRIVEN SHRA/TSRA DURING THE MORNING SOUTH
OF INTERSTATE 70 IN MO...OTHERWISE THE REMAINDER OF THE DAY SHOULD
BE MARKED BY SLIGHTLY COOLER TEMPERATURES WITH AN INCREASE IN CLOUDS
DURING THE LATER PART OF THE AFTERNOON AHEAD OF THE NEXT BIG SYSTEM.
THE MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH THE 12Z CYCLE
AND THE GENERAL CONSENSUS IS A MORE PROGRESSIVE SOLUTION WHICH THE
ECMWF HAS BEEN ADVERTISING FOR SEVERAL DAYS. CURRENT INDICATIONS ARE
THE AFOREMENTIONED PAC NW SHORT WAVE WILL DIG INTO THE
NORTHERN/CENTRAL PLAINS ON WEDNESDAY NIGHT AND AMPLIFY...WHILE A
LEAD IMPULSE TRACKS IN THE VICINITY OF THE OK/KS BORDER INTO SW MO
BY 12Z THURS. IN RESPONSE A LARGE REGION OF SIGNIFICANT LARGE SCALE
ASCENT IS FORECAST TO SPREAD INTO THE MS VALLEY WITH A 30-40 KT SLY
LOW LEVEL JET FOCUSING LOW LEVEL MOISTURE TRANSPORT AND LIFT AS
WELL. A LARGE REGION OF SHOWERS AND EMBEDDED ELEVATED THUNDERSTORMS
IS EXPECTED TO RESULT WITH MORE INTENSE CONVECTION ACROSS SOUTHERN
MO AND POINTS SOUTH. THERE ARE STILL SOME UNCERTAINTIES IN THE EXACT
EASTWARD SPREAD OF PRECIPITATION ON WED NIGHT...BUT THE MODEL
CONSENSUS WOULD BE TO AT LEAST THE MS RIVER BY DAYBREAK THURSDAY. THE
SHIELD OF PRECIPITATION SHOULD CONTINUE TO ADVANCE EAST ON THURSDAY
IN ASSOCIATION WITH CONTINUE PROGRESSION AND DIGGING OF THE UPPER
LOW/TROF INTO THE MS VALLEY. THE CLOUDS AND PRECIPITATION SHOULD
INHIBIT MUCH TEMPERATURE REBOUND. THE MAIN AREA OF PRECIPITATION
SHOULD THEN MOVE TO THE EAST INTO THE OH/TN VALLEY REGION ON
THURSDAY NIGHT AS THE DEEPENING YET PROGRESSIVE UPPER TROF
CONTINUES EASTWARD. THE HIGHEST POPS ON THURSDAY NIGHT WILL BE IN
SW AND SOUTH CENTRAL IL...TAPERING SIGNIFICANTLY BACK INTO CENTRAL
MO.
AN UNSEASONABLY COOL DAY LOOKS ON TAP FOR FRIDAY WITH THE UPPER LOW
AND TROF SLIDING EASTWARD AND DEEP CYCLONIC FLOW ACROSS THE AREA. AT
THE LEAST I AM EXPECTING EXTENSIVE STRATUS/STRATOCU...AND
POSSIBLY SOME SPOTTY INSTABILITY SHOWERS OVER THE NE HALF OF THE
CWA. H85 TEMPS OF +3/+5 DURING THE AFTERNOON ARE 2 TO 5 STANDARD
DEVIATIONS BELOW NORMAL...AND SUPPORT THE CURRENT FORECAST OF WELL
BELOW AVERAGE HIGHS FOR THE DAY.
THE BOUT OF COOL WEATHER LOOKS SHORT-LIVED HOWEVER WITH HEIGHTS
ALOFT ON THE RISE SAT-SUN AS THE DEEP UPPER TROF EXITS TO THE ENE
INTO THE WESTERN ATLANTIC. IN FACT...H5 HEIGHTS RISE SOME +240
METERS FROM 12Z SAT THRU 00Z SUN...AND BY MONDAY AFTERNOON THE LOW
LEVEL FLOW IS SSWLY WITH H85 TEMPS OF +20 TO +22. FROM LATE MONDAY
INTO TUESDAY WE WILL HAVE TO KEEP AN EYE ON A SAGGING WEST-EAST
FRONT AND POTENTIAL FOR THUNDERSTORMS.
GLASS
&&
.AVIATION...
ISSUED AT 705 PM CDT TUE MAY 29 2012
VFR CONDITIONS AND N SFC WNDS SLOWLY VEERING TO NE WILL BE THE
STORY OVER THE NEXT 24-30HRS AT THE TAF SITES. TWO UPPER LEVEL
DISTURBANCES WILL DICTATE THE WX OVER THE NEXT 24-36HRS AS A SFC
HI PRES BUILDS IN TONIGHT AND PERSISTS OVER THE AREA THRU MUCH OF
WEDNESDAY. THE FIRST DISTURBANCE IS SLATED TO MOVE THRU LATE
TONIGHT AND EARLY WEDNESDAY MORNING AND WILL COINCIDE WITH AND BE
JUST TO THE N OF EXPECTED MCS DEVELOPMENT OVER IN S CNTRL KS AND
WILL HELP TO PUSH LO PROBABILITIES OF RAIN MUCH FURTHER N AND NE
THAN WHERE THE MCS WILL TRACK. MODEL SOUNDINGS INDICATE FORCING
AND MOISTENING OCCURRING AT THE RIGHT TIME AND LOCATION TO WARRANT
A LO THREAT FOR SHRA/TSRA FOR THE I-70 CORRIDOR MAINLY IN MO
BETWEEN 08-13Z. PROBABILITY IS LO ENOUGH AT THIS TIME TO JUST
CONTINUE THE LOWER VFR CIGS MENTION AND WILL CONTINUE TO
MONITOR...AS WHAT DOES DEVELOP SHOULD BE ISOLD AT BEST. THIS
FORCING EXITS QUICKLY BY 13-14Z WEDNESDAY AND WILL LEAVE A PRETTY
DRY ATMOSPHERE BELOW 15KFT THRU THE REST OF THE VALID TAF PERIOD
AS SFC HI PRES DOMINATES MUCH OF THE REGION. THE SECOND UPPER
LEVEL DISTURBANCE WILL ROLL THRU LATER ON WEDNESDAY NIGHT AND INTO
THURSDAY AND SHOULD CARRY WITH IT NON-VFR CONDITIONS AND
WIDESPREAD PCPN...BUT THE TIMING OF IT FAVORED BY MOST MODELS WILL
NOT BRING IT IN UNTIL AFTER THE VALID PERIOD ENDS.
SPECIFICS FOR KSTL...VFR CONDITIONS AND LIGHT N SFC WNDS CAN BE
EXPECTED FOR MUCH OF THE VALID PERIOD...WITH SFC WNDS VEERING NE
LATE. ONLY PCPN EXPECTED IS LO PROBABILITY/ISOLD SHRA/TSRA IN A
WINDOW FROM 09-13Z...WITH SLIGHTLY BETTER CHCS ON THE SWRN METRO
AREA TOWARDS KSUS...AS AN UPPER LEVEL DISTURBANCE WILL TRY TO
OVERCOME INHIBITION AND GENERATE SOME ELEVATED CONVECTION.
PROBABILITIES AND EXPECTED COVERAGE ARE LO ENOUGH AT THIS TIME TO
JUST CONTINUE THE 7KFT CIG FOR LATER TONIGHT AND FOREGO VC OR
TEMPO WHICH WOULD BE HITTING IT TOO STRONG.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
316 PM MDT WED MAY 30 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY...
SCATTERED CONVECTIVE SHOWERS WITH POSSIBLY A LITTLE THUNDER ARE
AROUND THE REGION THIS EVENING. EXPECT ACTIVITY TO DECLINE AFTER
DARK AS UPPER FORCING IS LIMITED. HRRR HAS ACTIVITY ON DECLINE
AFTER 3Z. SHOWER ACTIVITY IS AIDED BY A VERY WEAK UPPER WAVE
EMBEDDED IN NORTHWESTERLY FLOW ALOFT. THIS WAVE BECOMES
UNIDENTIFIABLE IN THE MODELS AFTER 3Z.
MORE WEAK DISTURBANCES IN THE UPPER FLOW ARE EXPECTED TO GIVE A
CHANCE FOR SHOWERS AGAIN THURSDAY AFTERNOON INTO FRIDAY...WITH RIDGING
BEGINNING TO DOMINATE...AND SHOWERS ON THE DECLINE...LATER ON
FRIDAY.
SHORT TERM PATTERN OF AN APPROACHING RIDGE IS NOT CONDUCIVE TO
SURFACE LOW FORMATION AND SURFACE WINDS SHOULD REMAIN LIGHT
THROUGH FRIDAY. INCREASING HIGH PRESSURE WILL LEAD TO AN INCREASE
IN TEMPERATURES THE NEXT COUPLE DAYS WITH LOWS NEAR 50 AND HIGHS
INTO THE 70S. MARTIN
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
FRIDAY NIGHT AND SATURDAY THE REGION WILL BE UNDER THE INFLUENCE
OF AN UPPER RIDGE. HOWEVER AROUND SATURDAY EVENING A PAC-NW UPPER
TROUGH SENDS MOISTURE AND A COLD FRONT ACROSS NORTHEAST MONTANA.
CONVECTIVE PARAMETERS APPEAR STRONG FOR THE CENTRAL REGIONS TO OUR
WEST. BUT WEAKER PARAMETERS COULD SUPPORT GENERAL THUNDERSTORMS
AND POSSIBLY SUSTAIN ANY STRONG STORMS FOR A WHILE THAT MOVE INTO
OUR AREA. TIMING ISSUES BETWEEN THE GFS AND THE EC WILL MAINLY
AFFECT WHEN THE FRONT MEETS THE PEAK AREAS OF INSTABILITY. SO WX
TYPE IS SOMEWHAT UNCERTAIN.
MODELS IN GENERAL DO NOT AGREE WITH THE TIMING OF THE NEXT TROUGH
MOVING IN FROM THE WEST EARLY NEXT WEEK. BUT THERE IS LIMITED
AGREEMENT WITH A COLD FRONT AND OVERRUNNING MOISTURE SUNDAY NIGHT
AND MONDAY THAT WILL AFFECT MONTANA AND POSSIBLY NORTHEAST MONTANA
WITH SHOWERS.
BY TUESDAY THE EC AND GFS ARE TOTALLY OUT OF PHASE WITH THE TROUGH
MOVEMENT OVER THE WEST. THE PATTERN LOOKS WET IN GENERAL SO WILL
LEAVE POPS MOSTLY ALONE FOR NOW. THE WAVES ARE SO FAR OUT OF PHASE
AS TO PREVENT BLENDING. HPC THINKS THE EC HAS THE STRONGEST
SOLUTION BUT IS TOO WARM...AND THE GFS IS THE FASTEST. TAKING
SOMETHING OF A BLEND IT LOOKS LIKE NEXT WEEK WILL BE COOL AND WET.
THE LAST BIG STORM WAS NAILED BY THE EC AND IT IS TEMPTING TO
LEAN ON IT AGAIN. A NOTE LATE IN THE SHIFT FROM THE CPC SAYS
CONFIDENCE IN THE EC FOR THAT PERIOD IS ABOVE AVERAGE. BUT
WAITING FOR MORE AGREEMENT IS THE WAY TO GO FOR NOW.
BASED ON THE LATEST GUIDANCE A FEW GRID EDITS FOR POPS WERE MADE
TO DAY 3 NIGHT AND DAY 4...BUT LIMITED CHANGES ELSEWHERE. SCT
PREVIOUS DISCUSSION...
THE EXTENDED FORECAST PERIOD BEGINS WITH A MODERATELY-WELL
ESTABLISHED UPPER LEVEL RIDGE OVER THE SPINE OF THE THE ROCKY
MOUNTAINS AND THE ADJACENT NORTHERN HIGH PLAINS REGION.
UNFORTUNATELY...ONLY 24 HOURS LATER...THE GFS AND THE EC MODELS
BEGIN TO FALL OUT OF PHASE WITH ONE ANOTHER AND NEVER COME CLOSE
TO ANY KIND OF A CONSENSUS THEREAFTER. CONSEQUENTLY...CONFIDENCE IN
THE ACCURACY OF THE EXTENDED FORECAST IS SHAKY FOR SUNDAY AND GETS
ONLY WORSE THROUGHOUT THE REMAINDER OF THE EXTENDED FORECAST
PERIOD.
THE VERY GENERAL WEATHER PATTERN TRENDS I THINK WILL GO AS
FOLLOWS...
SUNDAY THROUGH MONDAY NIGHT...SOUTHWEST FLOW ALOFT INCREASES IN
RESPONSE TO AN APPROACHING AND DEEPENING WEST COAST UPPER LEVEL
TROUGH. EXACTLY HOW THIS TROUGH EVOLVES IS HANDLED COMPLETELY
DIFFERENTLY DEPENDING ON WHICH MODEL YOU TRUST. THE EC DIG THE
TROUGH INTO A CLOSED UPPER LOW AS FAR SOUTH AS DEATH VALLEY
CALIFORNIA BE EARLY WEDNESDAY WHILE THE GFS MESSES AROUND WITH A
SIMPLE OPEN WAVE OVER THE CENTRAL AND NORTHERN ROCKIES WHICH
DISAPPEARS VERY QUICKLY. BEYOND THEN...ANY SEMBLANCE OF MODEL
CONSENSUS IS GONE. OVERALL THE GFS IS THE VERY WET MODEL AND THE
EC IS THE VERY DRY MODEL. LOWEST FORECAST CONFIDENCE I HAVE HAD IN
QUITE SOME TIME FOR THE EXTENDED PERIOD. BMICKELSON
&&
.AVIATION...
UNSTABLE AIR...BEHIND A COLD FRONT THAT PUSHED THROUGH NORTHEAST
MONTANA THIS MORNING...HAS SPAWNED CONVECTION WITH ISOLATED RAIN
SHOWERS AND LIGHTNING STRIKES. ISOLATED THUNDERSTORMS WILL
DIMINISH DURING THE EVENING BUT WITH A SURFACE TROUGH AND
OVERRUNNING MOISTURE OVER THE STATIONARY COLD BOUNDARY ISOLATED
RAIN SHOWERS WILL CONTINUE INTO THURSDAY...GENERALLY SHIFTING
EAST. THE SHIFTING OF THE SURFACE TROUGH WILL SHIFT SE WINDS OF
AROUND 10KT TO THE WEST THROUGH THURSDAY. SCT
&&
.HYDROLOGY...
THE RECENT HEAVY RAINFALL CONTINUES TO MAKE ITS WAY INTO MAIN STEM
RIVERS. BEAVER CREEK NEAR HINSDALE AND THE FRENCHMAN CREEK NEAR
THE INTERNATIONAL BORDER HAVE RECORDED STREAM CRESTS. THE POPLAR
RIVER NEAR THE INTERNATIONAL BORDER HAS RISEN TO ACTION
STAGE...BUT APPEARS TO HAVE CRESTED.
THE LATEST MILK RIVER FORECASTS KEEP ALL POINTS BELOW ACTION
STAGE. THE MILK RIVER AT GLASGOW IS EXPECTED TO CREST AT 18.0 FT
LATE THIS AFTERNOON AND NASHUA SHOULD CREST AT 11.3 FT LATE
THURSDAY AFTERNOON. TAMPICO CRESTED AT 15.7 FT AROUND NOON AND IS
NOW FALLING. AREA CREEKS AND SMALLER TRIBUTARIES WILL CONTINUE TO
RUN HIGH FOR A COUPLE OF DAYS AS THE GENERAL 1.3 TO 2.7 INCHES OF
RECENT RAINFALL DRAINS THROUGH THE BASINS. SCT
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
146 PM CDT WED MAY 30 2012
.UPDATE...MORNING UPPER AIR ANALYSIS INDICATES QUASI-ZONAL TO
NORTHWESTERLY MID AND UPPER LEVEL FLOW ACROSS CENTRAL PORTIONS OF
THE CONUS...WITH SUBTLE RIDGING ACROSS THE WESTERN AND EASTERN
CONUS. MID AND UPPER LEVEL JET ENERGY IS POSITIONED FROM THE
NORTHWESTERN CONUS...ACROSS CENTRAL PORTIONS OF THE CONUS AND ON
INTO THE EASTERN CONUS. EARLY AFTERNOON WATER VAPOR IMAGERY SHOWS
INCREASED VALUES OF MID LEVEL MOISTURE FLOWING IN FROM THE
PACIFIC...PUSHING ACROSS THE NORTHWESTERN CONUS AND INTO THE
CENTRAL PLAINS. A MID LEVEL SHORT WAVE IS ALSO NOTED OVER THE
NORTHERN PLAINS...MOVING EAST/SOUTHEAST. AT THE SURFACE AN AREA OF
HIGH PRESSURE IS LOCATED OVER THE UPPER MISSISSIPPI VALLEY...WITH
LOW LEVEL RETURN FLOW ON THE BACK SIDE OF THE SURFACE RIDGE
INFILTRATING PORTIONS OF THE CENTRAL PLAINS. CONVECTIVELY INDUCED
OUTFLOW AT THE SURFACE HOWEVER IS PROMOTING A BIT MORE CHAOTIC
LOW LEVEL WIND FIELD ACROSS OUR CWA...THAN THAT OF THE TRUE
SOUTHEASTERLY WINDS WHICH ARE TRYING TO DEVELOP. KUEX INDICATES
CONVECTION PERSISTING ACROSS MUCH OF SOUTH CENTRAL NEBRASKA EARLY
THIS AFTERNOON.
LOW LEVEL RETURN FLOW IS HELPING PROMOTE LOW LEVEL THERMAL
ADVECTION AND RESULTANT ISENTROPIC UPGLIDE AND SATURATION OVER OUR
CWA...PRIMARILY ALONG THE 300-310K SURFACES. LAPS PROXIMITY
SOUNDINGS FROM ACROSS OUR WESTERN CWA SUGGEST AIR
PARCELS...ASCENDING FROM AROUND 700MB...ARE CONTENDING WITH LESS
THAN 30J/KG CIN AND 600-1000J/KG CAPE. IN ADDITION...MID AND UPPER
LEVEL JET ENERGY IS ALSO HELPING PROMOTE DEEP LAYER BULK SHEAR
VALUES OF 30-40KTS. EVEN THOUGH THE INSTABILITY IS NOT
PARTICULARLY IMPRESSIVE...THE COOL LOW TO MID LEVEL AIRMASS IN
PLACE AND THE DEEP LAYER SHEAR ARE MORE THAN COMPENSATING...WITH
SEVERAL REPORTS OF QUARTER-SIZE HAIL ALREADY REPORTED ACROSS THE
AREA THIS MORNING. BROAD-SCALE ASCENT SHOULD PERSIST THROUGH THE
REST OF THIS AFTERNOON...WITH DEEP LAYER SHEAR AND INSTABILITY
ALSO LIKELY PERSISTING. SEVERE WEATHER WILL REMAIN POSSIBLE ACROSS
THE ENTIRE CWA THROUGH THE AFTERNOON HOURS AS A RESULT.
WENT AHEAD AND UPDATED THE AFTERNOON FORECAST TO BETTER REFLECT
CURRENT CONVECTIVE ACTIVITY. ALSO TWEAKED HOURLY GRIDS TO BETTER
REFLECT CURRENT TRENDS.
&&
.PREV DISCUSSION... /ISSUED 1251 PM CDT WED MAY 30 2012/
AVIATION...18Z KGRI TAF. A COUPLE ROUNDS OF THUNDERSTORMS ARE
POSSIBLE THIS AFTERNOON AND EVENING. CEILINGS AND VISIBILITIES
COULD VARY MORE THAN WHAT THE TAF MAY INDICATE.
PREV DISCUSSION... /ISSUED 438 AM CDT WED MAY 30 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
THE MAIN FOCUS OF THE SHORT TERM PERIOD WILL BE ON THE NEXT 24 TO 36
HOURS AS AN UPPER LEVEL WAVE SLIDES THROUGH THE REGION.
UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL TROUGH AXIS PUSHING
EASTWARD ACROSS THE GREAT LAKES REGION AND THE OHIO RIVER
VALLEY...HELPING TO BREAK DOWN AN UPPER LEVEL RIDGE ACROSS THE EAST
COAST. A SECONDARY RIDGE AXIS HAS PUSHED ON THE WEST COAST...AND
WATER VAPOR IMAGERY DEPICTS A MID TO UPPER LEVEL SHORT WAVE
PERTURBATION MOVING SOUTHEAST ACROSS MONTANA AND WYOMING. A FEW
SCATTERED RETURNS HAVE BEGUN TO SHOW UP ON RADAR ACROSS THE NEBRASKA
PANHANDLE ALTHOUGH ANY PRECIPITATION IS LIKELY NOT HITTING THE
GROUND AT THE CURRENT TIME.
THERE REMAINS SOME DISCREPANCIES REGARDING PRECIPITATION CHANCES AS
THE WAVE MOVES CLOSER ESPECIALLY BEFORE THE 18Z TIME FRAME. THE SREF
AND GFS BOTH EXPECT POPS TO FILL IN ACROSS THE WESTERN CENTRAL
PLAINS ALONG THE TROUGH AXIS. WHILE THE NAM...EC AND 4 KM WRF KEEP
POPS ACROSS CENTRAL AND NORTHERN NEBRASKA THROUGH THE MORNING HOURS.
THE HRRR REMAINS THE OUTLIER WITH VERY LITTLE POPS GENERATED AT ALL.
REGRETTABLY...FILLING IN OF THE POPS ALONG THE TROUGH THIS MORNING
DOES NOT LOOK TO BE THE CASE...BUT STILL EXPECTING HIGHER POPS
ACROSS THE NORTH AND WEST.
REGARDING POPS THIS AFTERNOON...AS THE OPEN WAVE PUSHES CLOSER TO
THE PLAINS...EXPECTING MORE DEVELOPMENT ALONG THE TROUGH
AXIS...ESPECIALLY ACROSS SOUTH CENTRAL NEBRASKA. THE BEST
INSTABILITY REMAINS FARTHER SOUTH ALONG THE SURFACE LOW...HOWEVER
THE GFS DOES ADVERTISE NEARLY 1500 J/KG OF ELEVATED CAPE SKIRTING
ACROSS THE WESTERN PORTION OF THE FORECAST AREA WITH THE HIGHER AXIS
ACROSS SOUTHWEST NEBRASKA. GIVEN THIS...DECIDED TO CONTINUE MENTION
OF SEVERE WORDING IN THE HWO ESPECIALLY ACROSS THE FAR WEST. BULK
SHEAR VECTORS FROM 0 TO 6 KM ALSO ARE INDICATIVE OF SEVERE CHANCES
WITH NEARLY 35 TO 50 KTS ACROSS SOUTHWEST NEBRASKA. THE FAR
NORTHEAST WILL LIKELY REMAIN THUNDERSTORM FREE WITH VERY LITTLE CAPE
EXPECTED ACROSS THE AREA.
FOR THE OVERNIGHT HOURS ON WEDNESDAY...THE SREF...NAM...GFS...AND
ECMWF ALL SUGGEST CONTINUED POPS ACROSS THE AREA AS THE OVEN WAVE
PUSHES PAST THE REGION. INSTABILITY PARAMETERS DECREASE DRASTICALLY DURING
THE OVERNIGHT HOURS ON WEDNESDAY...THUS EXPECTING MORE SCATTERED
LIGHT SHOWERS DURING THE OVERNIGHT HOURS.
SURFACE HIGH BEGINS TO SLIDE SOUTH ACROSS THE REGION BY FRIDAY AS
THE UPPER LEVEL RIDGE BUILDS EASTWARD. EXPECTING SHOWERS TO COME TO
AN END FROM WEST TO EAST BY EARLY THURSDAY MORNING...COMPLETELY
CLEARING THE FORECAST AREA BY THURSDAY.
BY FRIDAY AFTERNOON...A SECONDARY WEAK UPPER WAVE COMBINED WITH
POSITIVE VORTICITY ADVECTION...SLIDES THROUGH THE FORECAST AREA.
DEVELOPING SURFACE LOW PRESSURE ALONG THE FRONT RANGE COULD GENERATE
ENOUGH LIFT TO DEVELOP SCATTERED THUNDERSTORMS THAT MOVE THROUGH THE
REGION. THE GFS INDICATES NEAR 1000 J/KG OF MOST UNSTABLE CAPE
NOSING INTO THE FAR SOUTHEAST PORTION OF THE FORECAST AREA...BEFORE
QUICKLY DECREASING AGAIN WITH NIGHTFALL. THUS ANY THUNDERSTORM
DEVELOPMENT WILL LIKELY BE ACROSS THE WEST SOUTHWEST DURING THE
AFTERNOON HOURS.
MADE VERY FEW CHANGES TO TEMPERATURES IN THE LONG TERM. EXPECTING
TEMPERATURES TODAY AND THURSDAY TO BE QUITE TRICKY DEPENDING BOTH ON
PRECIPITATION CHANCES AND RESULTANT CLOUD COVER. WENT WITH LOWER 60S
ACROSS THE NORTH AND LOWER 70S ACROSS THE SOUTH FOR TODAY...WHILE
EXPECT MUCH OF AREA ON THURSDAY TO REMAIN IN THE 60S. BUMPED UP
HIGHS A BIT ON FRIDAY...AS WARM AIR ADVECTION RETURNS TO THE
FORECAST AREA UNDER THE UPPER LEVEL RIDGE. SOUNDINGS INDICATE GOOD
MIXING DURING THE DAY TO NEARLY 800 MB. GIVEN PRECIPITATION CHANCES
AND CLOUD COVER...STILL EXPECTING TEMPERATURES TO CLIMB TO THE MID
TO UPPER 70S.
LONG TERM...SATURDAY THROUGH TUESDAY. WARMER WEATHER WILL RETURN TO
THE REGION ALONG WITH A FEW CHANCES OF SHOWERS AND THUNDERSTORMS.
SATURDAY...AN UPPER LEVEL RIDGE WILL START TO BUILD INTO THE CENTRAL
PLAINS AND TEMPERATURES WILL BEGIN A NOTABLE WARMING TREND. DRY
CONDITIONS ARE EXPECTED.
SUNDAY...AN UPPER LEVEL RIDGE WILL BE CENTERED OVER THE PLAINS
RESULTING IN HOT WEATHER WITH HIGHS IN THE UPPER 80S TO LOWER 90S.
THE 00Z ECMWF AND GFS ARE BOTH SHOWING A WEAK 500MB VORT MAX
TRACKING BENEATH THE UPPER RIDGE ACROSS OUR AREA LEADING TO A LOW
END CHANCE OF SHOWERS AND THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT.
MONDAY AND TUESDAY...THE UPPER LEVEL RIDGE REMAINS NEARLY STATIONARY
OVER THE PLAINS WITH CONTINUED VERY WARM TO HOT CONDITIONS. HIGHS
WILL BE IN THE 80S WITH SOME LOWER 90S ACROSS SOUTHERN ZONES. OUR
MODEL BLEND PROCEDURE SHOWS DRY CONDITIONS FOR MOST AREAS ON MONDAY
BUT CHANCE POPS ON TUESDAY WITH A WEAK VORT MAX TRYING TO PRESS UP
ON THE UPPER RIDGE. WILL CARRY THE POPS ON TUESDAY...BUT LOWERED
THEM BY 20 PERCENT BELOW CONSALL MODEL BLEND DUE TO DOUBTS ABOUT
VERY MANY THUNDERSTORMS BEING ABLE TO FORM UNDER A RATHER DOMINATING
UPPER RIDGE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...BRYANT
AVIATION...HEINLEIN
SHORT TERM...SATLZMAN
LONG TERM...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1251 PM CDT WED MAY 30 2012
.AVIATION...18Z KGRI TAF. A COUPLE ROUNDS OF THUNDERSTORMS ARE
POSSIBLE THIS AFTERNOON AND EVENING. CEILINGS AND VISIBILITIES
COULD VARY MORE THAN WHAT THE TAF MAY INDICATE.
&&
PREV DISCUSSION... /ISSUED 438 AM CDT WED MAY 30 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
THE MAIN FOCUS OF THE SHORT TERM PERIOD WILL BE ON THE NEXT 24 TO 36
HOURS AS AN UPPER LEVEL WAVE SLIDES THROUGH THE REGION.
UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL TROUGH AXIS PUSHING
EASTWARD ACROSS THE GREAT LAKES REGION AND THE OHIO RIVER
VALLEY...HELPING TO BREAK DOWN AN UPPER LEVEL RIDGE ACROSS THE EAST
COAST. A SECONDARY RIDGE AXIS HAS PUSHED ON THE WEST COAST...AND
WATER VAPOR IMAGERY DEPICTS A MID TO UPPER LEVEL SHORT WAVE
PERTURBATION MOVING SOUTHEAST ACROSS MONTANA AND WYOMING. A FEW
SCATTERED RETURNS HAVE BEGUN TO SHOW UP ON RADAR ACROSS THE NEBRASKA
PANHANDLE ALTHOUGH ANY PRECIPITATION IS LIKELY NOT HITTING THE
GROUND AT THE CURRENT TIME.
THERE REMAINS SOME DISCREPANCIES REGARDING PRECIPITATION CHANCES AS
THE WAVE MOVES CLOSER ESPECIALLY BEFORE THE 18Z TIME FRAME. THE SREF
AND GFS BOTH EXPECT POPS TO FILL IN ACROSS THE WESTERN CENTRAL
PLAINS ALONG THE TROUGH AXIS. WHILE THE NAM...EC AND 4 KM WRF KEEP
POPS ACROSS CENTRAL AND NORTHERN NEBRASKA THROUGH THE MORNING HOURS.
THE HRRR REMAINS THE OUTLIER WITH VERY LITTLE POPS GENERATED AT ALL.
REGRETTABLY...FILLING IN OF THE POPS ALONG THE TROUGH THIS MORNING
DOES NOT LOOK TO BE THE CASE...BUT STILL EXPECTING HIGHER POPS
ACROSS THE NORTH AND WEST.
REGARDING POPS THIS AFTERNOON...AS THE OPEN WAVE PUSHES CLOSER TO
THE PLAINS...EXPECTING MORE DEVELOPMENT ALONG THE TROUGH
AXIS...ESPECIALLY ACROSS SOUTH CENTRAL NEBRASKA. THE BEST
INSTABILITY REMAINS FARTHER SOUTH ALONG THE SURFACE LOW...HOWEVER
THE GFS DOES ADVERTISE NEARLY 1500 J/KG OF ELEVATED CAPE SKIRTING
ACROSS THE WESTERN PORTION OF THE FORECAST AREA WITH THE HIGHER AXIS
ACROSS SOUTHWEST NEBRASKA. GIVEN THIS...DECIDED TO CONTINUE MENTION
OF SEVERE WORDING IN THE HWO ESPECIALLY ACROSS THE FAR WEST. BULK
SHEAR VECTORS FROM 0 TO 6 KM ALSO ARE INDICATIVE OF SEVERE CHANCES
WITH NEARLY 35 TO 50 KTS ACROSS SOUTHWEST NEBRASKA. THE FAR
NORTHEAST WILL LIKELY REMAIN THUNDERSTORM FREE WITH VERY LITTLE CAPE
EXPECTED ACROSS THE AREA.
FOR THE OVERNIGHT HOURS ON WEDNESDAY...THE SREF...NAM...GFS...AND
ECMWF ALL SUGGEST CONTINUED POPS ACROSS THE AREA AS THE OVEN WAVE
PUSHES PAST THE REGION. INSTABILITY PARAMETERS DECREASE DRASTICALLY DURING
THE OVERNIGHT HOURS ON WEDNESDAY...THUS EXPECTING MORE SCATTERED
LIGHT SHOWERS DURING THE OVERNIGHT HOURS.
SURFACE HIGH BEGINS TO SLIDE SOUTH ACROSS THE REGION BY FRIDAY AS
THE UPPER LEVEL RIDGE BUILDS EASTWARD. EXPECTING SHOWERS TO COME TO
AN END FROM WEST TO EAST BY EARLY THURSDAY MORNING...COMPLETELY
CLEARING THE FORECAST AREA BY THURSDAY.
BY FRIDAY AFTERNOON...A SECONDARY WEAK UPPER WAVE COMBINED WITH
POSITIVE VORTICITY ADVECTION...SLIDES THROUGH THE FORECAST AREA.
DEVELOPING SURFACE LOW PRESSURE ALONG THE FRONT RANGE COULD GENERATE
ENOUGH LIFT TO DEVELOP SCATTERED THUNDERSTORMS THAT MOVE THROUGH THE
REGION. THE GFS INDICATES NEAR 1000 J/KG OF MOST UNSTABLE CAPE
NOSING INTO THE FAR SOUTHEAST PORTION OF THE FORECAST AREA...BEFORE
QUICKLY DECREASING AGAIN WITH NIGHTFALL. THUS ANY THUNDERSTORM
DEVELOPMENT WILL LIKELY BE ACROSS THE WEST SOUTHWEST DURING THE
AFTERNOON HOURS.
MADE VERY FEW CHANGES TO TEMPERATURES IN THE LONG TERM. EXPECTING
TEMPERATURES TODAY AND THURSDAY TO BE QUITE TRICKY DEPENDING BOTH ON
PRECIPITATION CHANCES AND RESULTANT CLOUD COVER. WENT WITH LOWER 60S
ACROSS THE NORTH AND LOWER 70S ACROSS THE SOUTH FOR TODAY...WHILE
EXPECT MUCH OF AREA ON THURSDAY TO REMAIN IN THE 60S. BUMPED UP
HIGHS A BIT ON FRIDAY...AS WARM AIR ADVECTION RETURNS TO THE
FORECAST AREA UNDER THE UPPER LEVEL RIDGE. SOUNDINGS INDICATE GOOD
MIXING DURING THE DAY TO NEARLY 800 MB. GIVEN PRECIPITATION CHANCES
AND CLOUD COVER...STILL EXPECTING TEMPERATURES TO CLIMB TO THE MID
TO UPPER 70S.
LONG TERM...SATURDAY THROUGH TUESDAY. WARMER WEATHER WILL RETURN TO
THE REGION ALONG WITH A FEW CHANCES OF SHOWERS AND THUNDERSTORMS.
SATURDAY...AN UPPER LEVEL RIDGE WILL START TO BUILD INTO THE CENTRAL
PLAINS AND TEMPERATURES WILL BEGIN A NOTABLE WARMING TREND. DRY
CONDITIONS ARE EXPECTED.
SUNDAY...AN UPPER LEVEL RIDGE WILL BE CENTERED OVER THE PLAINS
RESULTING IN HOT WEATHER WITH HIGHS IN THE UPPER 80S TO LOWER 90S.
THE 00Z ECMWF AND GFS ARE BOTH SHOWING A WEAK 500MB VORT MAX
TRACKING BENEATH THE UPPER RIDGE ACROSS OUR AREA LEADING TO A LOW
END CHANCE OF SHOWERS AND THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT.
MONDAY AND TUESDAY...THE UPPER LEVEL RIDGE REMAINS NEARLY STATIONARY
OVER THE PLAINS WITH CONTINUED VERY WARM TO HOT CONDITIONS. HIGHS
WILL BE IN THE 80S WITH SOME LOWER 90S ACROSS SOUTHERN ZONES. OUR
MODEL BLEND PROCEDURE SHOWS DRY CONDITIONS FOR MOST AREAS ON MONDAY
BUT CHANCE POPS ON TUESDAY WITH A WEAK VORT MAX TRYING TO PRESS UP
ON THE UPPER RIDGE. WILL CARRY THE POPS ON TUESDAY...BUT LOWERED
THEM BY 20 PERCENT BELOW CONSALL MODEL BLEND DUE TO DOUBTS ABOUT
VERY MANY THUNDERSTORMS BEING ABLE TO FORM UNDER A RATHER DOMINATING
UPPER RIDGE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
438 AM CDT WED MAY 30 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
THE MAIN FOCUS OF THE SHORT TERM PERIOD WILL BE ON THE NEXT 24 TO 36
HOURS AS AN UPPER LEVEL WAVE SLIDES THROUGH THE REGION.
UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL TROUGH AXIS PUSHING
EASTWARD ACROSS THE GREAT LAKES REGION AND THE OHIO RIVER
VALLEY...HELPING TO BREAK DOWN AN UPPER LEVEL RIDGE ACROSS THE EAST
COAST. A SECONDARY RIDGE AXIS HAS PUSHED ON THE WEST COAST...AND
WATER VAPOR IMAGERY DEPICTS A MID TO UPPER LEVEL SHORT WAVE
PERTURBATION MOVING SOUTHEAST ACROSS MONTANA AND WYOMING. A FEW
SCATTERED RETURNS HAVE BEGUN TO SHOW UP ON RADAR ACROSS THE NEBRASKA
PANHANDLE ALTHOUGH ANY PRECIPITATION IS LIKELY NOT HITTING THE
GROUND AT THE CURRENT TIME.
THERE REMAINS SOME DISCREPANCIES REGARDING PRECIPITATION CHANCES AS
THE WAVE MOVES CLOSER ESPECIALLY BEFORE THE 18Z TIME FRAME. THE SREF
AND GFS BOTH EXPECT POPS TO FILL IN ACROSS THE WESTERN CENTRAL
PLAINS ALONG THE TROUGH AXIS. WHILE THE NAM...EC AND 4 KM WRF KEEP
POPS ACROSS CENTRAL AND NORTHERN NEBRASKA THROUGH THE MORNING HOURS.
THE HRRR REMAINS THE OUTLIER WITH VERY LITTLE POPS GENERATED AT ALL.
REGRETTABLY...FILLING IN OF THE POPS ALONG THE TROUGH THIS MORNING
DOES NOT LOOK TO BE THE CASE...BUT STILL EXPECTING HIGHER POPS
ACROSS THE NORTH AND WEST.
REGARDING POPS THIS AFTERNOON...AS THE OPEN WAVE PUSHES CLOSER TO
THE PLAINS...EXPECTING MORE DEVELOPMENT ALONG THE TROUGH
AXIS...ESPECIALLY ACROSS SOUTH CENTRAL NEBRASKA. THE BEST
INSTABILITY REMAINS FARTHER SOUTH ALONG THE SURFACE LOW...HOWEVER
THE GFS DOES ADVERTISE NEARLY 1500 J/KG OF ELEVATED CAPE SKIRTING
ACROSS THE WESTERN PORTION OF THE FORECAST AREA WITH THE HIGHER AXIS
ACROSS SOUTHWEST NEBRASKA. GIVEN THIS...DECIDED TO CONTINUE MENTION
OF SEVERE WORDING IN THE HWO ESPECIALLY ACROSS THE FAR WEST. BULK
SHEAR VECTORS FROM 0 TO 6 KM ALSO ARE INDICATIVE OF SEVERE CHANCES
WITH NEARLY 35 TO 50 KTS ACROSS SOUTHWEST NEBRASKA. THE FAR
NORTHEAST WILL LIKELY REMAIN THUNDERSTORM FREE WITH VERY LITTLE CAPE
EXPECTED ACROSS THE AREA.
FOR THE OVERNIGHT HOURS ON WEDNESDAY...THE SREF...NAM...GFS...AND
ECMWF ALL SUGGEST CONTINUED POPS ACROSS THE AREA AS THE OVEN WAVE
PUSHES PAST THE REGION. INSTABILITY PARAMETERS DECREASE DRASTICALLY DURING
THE OVERNIGHT HOURS ON WEDNESDAY...THUS EXPECTING MORE SCATTERED
LIGHT SHOWERS DURING THE OVERNIGHT HOURS.
SURFACE HIGH BEGINS TO SLIDE SOUTH ACROSS THE REGION BY FRIDAY AS
THE UPPER LEVEL RIDGE BUILDS EASTWARD. EXPECTING SHOWERS TO COME TO
AN END FROM WEST TO EAST BY EARLY THURSDAY MORNING...COMPLETELY
CLEARING THE FORECAST AREA BY THURSDAY.
BY FRIDAY AFTERNOON...A SECONDARY WEAK UPPER WAVE COMBINED WITH
POSITIVE VORTICITY ADVECTION...SLIDES THROUGH THE FORECAST AREA.
DEVELOPING SURFACE LOW PRESSURE ALONG THE FRONT RANGE COULD GENERATE
ENOUGH LIFT TO DEVELOP SCATTERED THUNDERSTORMS THAT MOVE THROUGH THE
REGION. THE GFS INDICATES NEAR 1000 J/KG OF MOST UNSTABLE CAPE
NOSING INTO THE FAR SOUTHEAST PORTION OF THE FORECAST AREA...BEFORE
QUICKLY DECREASING AGAIN WITH NIGHTFALL. THUS ANY THUNDERSTORM
DEVELOPMENT WILL LIKELY BE ACROSS THE WEST SOUTHWEST DURING THE
AFTERNOON HOURS.
MADE VERY FEW CHANGES TO TEMPERATURES IN THE LONG TERM. EXPECTING
TEMPERATURES TODAY AND THURSDAY TO BE QUITE TRICKY DEPENDING BOTH ON
PRECIPITATION CHANCES AND RESULTANT CLOUD COVER. WENT WITH LOWER 60S
ACROSS THE NORTH AND LOWER 70S ACROSS THE SOUTH FOR TODAY...WHILE
EXPECT MUCH OF AREA ON THURSDAY TO REMAIN IN THE 60S. BUMPED UP
HIGHS A BIT ON FRIDAY...AS WARM AIR ADVECTION RETURNS TO THE
FORECAST AREA UNDER THE UPPER LEVEL RIDGE. SOUNDINGS INDICATE GOOD
MIXING DURING THE DAY TO NEARLY 800 MB. GIVEN PRECIPITATION CHANCES
AND CLOUD COVER...STILL EXPECTING TEMPERATURES TO CLIMB TO THE MID
TO UPPER 70S.
.LONG TERM...SATURDAY THROUGH TUESDAY. WARMER WEATHER WILL RETURN TO
THE REGION ALONG WITH A FEW CHANCES OF SHOWERS AND THUNDERSTORMS.
SATURDAY...AN UPPER LEVEL RIDGE WILL START TO BUILD INTO THE CENTRAL
PLAINS AND TEMPERATURES WILL BEGIN A NOTABLE WARMING TREND. DRY
CONDITIONS ARE EXPECTED.
SUNDAY...AN UPPER LEVEL RIDGE WILL BE CENTERED OVER THE PLAINS
RESULTING IN HOT WEATHER WITH HIGHS IN THE UPPER 80S TO LOWER 90S.
THE 00Z ECMWF AND GFS ARE BOTH SHOWING A WEAK 500MB VORT MAX
TRACKING BENEATH THE UPPER RIDGE ACROSS OUR AREA LEADING TO A LOW
END CHANCE OF SHOWERS AND THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT.
MONDAY AND TUESDAY...THE UPPER LEVEL RIDGE REMAINS NEARLY STATIONARY
OVER THE PLAINS WITH CONTINUED VERY WARM TO HOT CONDITIONS. HIGHS
WILL BE IN THE 80S WITH SOME LOWER 90S ACROSS SOUTHERN ZONES. OUR
MODEL BLEND PROCEDURE SHOWS DRY CONDITIONS FOR MOST AREAS ON MONDAY
BUT CHANCE POPS ON TUESDAY WITH A WEAK VORT MAX TRYING TO PRESS UP
ON THE UPPER RIDGE. WILL CARRY THE POPS ON TUESDAY...BUT LOWERED
THEM BY 20 PERCENT BELOW CONSALL MODEL BLEND DUE TO DOUBTS ABOUT
VERY MANY THUNDERSTORMS BEING ABLE TO FORM UNDER A RATHER DOMINATING
UPPER RIDGE.
&&
.AVIATION...06Z KGRI TAF. CONFIDENCE REMAINS FAIRLY HIGH THAT THE
VAST MAJORITY OF THE PERIOD WILL SEE VFR CATEGORY
CEILING/VISIBILITY. HOWEVER...PASSING SHOWERS AND THUNDERSTORMS
DURING THE DAY COULD BRIEFLY RESULT IN MVFR VISIBILITY CONDITIONS
SUCH AS A FEW 5SM OBS. A MID LEVEL CLOUD DECK WILL ARRIVE BY AROUND
SUNRISE. DAYTIME HOURS ON WEDNESDAY...MORE THAN ONE ROUND OF
SHOWERS/STORMS IS POSSIBLE...BUT IT SHOULD NOT BE ANY KIND OF ALL
DAY RAINOUT. ANY STORMS THAT MIGHT AFFECT KGRI DURING THE TAF
VALID PERIOD SHOULD REMAIN BELOW SEVERE LIMITS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM/AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
103 AM CDT WED MAY 30 2012
.AVIATION...06Z KGRI TAF. CONFIDENCE REMAINS FAIRLY HIGH THAT THE
VAST MAJORITY OF THE PERIOD WILL SEE VFR CATEGORY
CEILING/VISIBILITY. HOWEVER...PASSING SHOWERS AND THUNDERSTORMS
DURING THE DAY COULD BRIEFLY RESULT IN MVFR VISIBILITY CONDITIONS
SUCH AS A FEW 5SM OBS. A MID LEVEL CLOUD DECK WILL ARRIVE BY AROUND
SUNRISE. DAYTIME HOURS ON WEDNESDAY...MORE THAN ONE ROUND OF
SHOWERS/STORMS IS POSSIBLE...BUT IT SHOULD NOT BE ANY KIND OF ALL
DAY RAINOUT. ANY STORMS THAT MIGHT AFFECT KGRI DURING THE TAF
VALID PERIOD SHOULD REMAIN BELOW SEVERE LIMITS.
&&
.PREV DISCUSSION... /ISSUED 1107 PM CDT TUE MAY 29 2012/
UPDATE...RECENTLY COMPLETED A RELATIVELY MINOR UPDATE FOR THE
OVERNIGHT HOURS. PRIMARY CHANGE WAS TO PULL ALL MENTION OF
SHOWERS/STORMS BEFORE 09Z...AND ALTHOUGH KEPT AT LEAST A SLIGHT
CHANCE ALL AREAS AFTER 09Z...PULLED THUNDER MENTION FROM A HANDFUL
OF NORTHEAST/EASTERN COUNTIES. FOR THE EARLY PORTION OF THE
OVERNIGHT HOURS...A FEW ELEVATED STORMS WILL CONTINUE BLOSSOMING
ACROSS PARTS OF EAST CENTRAL/NORTHEAST KS...BUT SHOULD REMAIN AT
LEAST 50 MILES OR SO SOUTHEAST OF THE EXTREME SOUTHEASTERN CWA.
THIS CONVECTION SEEMS BEST TIED TO THETA-E ADVECTION AROUND THE
700MB LEVEL...ALONG THE FAR NORTHERN EDGE OF THE NORTHWARD-
RETURNING INSTABILITY AXIS. BETTER CHANCES FOR STORMS WITHIN THE
CWA WILL HAVE TO WAIT UNTIL VERY LATE TONIGHT INTO WEDNESDAY
MORNING...WHEN MID LEVEL FRONTOGENESIS/SATURATION INCREASES FROM
THE NORTHWEST...AND ANOTHER SURGE OF THETA-E ADVECTION IN THE
850-700MB LAYER TAKES PLACE...BUT THIS TIME AIMED MUCH MORE SO
INTO AT LEAST SOUTHWEST PARTS OF THE CWA. MODEL QPF IS ALL OVER
THE PLACE...WITH THE LATEST HRRR RUNS BARELY BRINGING ANYTHING
INTO THE CWA BEFORE SUNRISE...WHILE BOTH THE 00Z NAM/GFS AT LEAST
BRING SOME ACTIVITY INTO THE SOUTHWEST COUNTIES. ALTHOUGH NOT
NECESSARILY ANTICIPATING A LATE NIGHT/EARLY MORNING SEVERE
THREAT...INSERTED PENNY SIZE HAIL MENTION INTO THE HWO TO ACCOUNT
FOR THE NAM DEPICTION OF 500-1000+ J/KG MUCAPE INTO
SOUTHERN/SOUTHWEST ZONES. AS MENTIONED BEFORE...PULLED ALL
OVERNIGHT THUNDER MENTION FROM NORTHEAST ZONES AS SUFFICIENT
ELEVATED INSTABILITY SHOULD STRUGGLE TO REACH NORTHEAST OF AN ORD-
GENEVA LINE. MADE VERY LITTLE IF ANY CHANGE TO OVERNIGHT LOW
TEMPS...BUT NUDGED DOWN 1 DEGREE OR SO SOME AREAS BASED ON LATEST
HOURLY GFS LAMP GUIDANCE...AIMING FOR A RANGE FROM MID-UPPER 40S
FAR NORTH...TO MID 50S IN KS ZONES.
PREV DISCUSSION... /ISSUED 344 PM CDT TUE MAY 29 2012/
SHORT TERM...TONIGHT AND WEDNESDAY. BIGGEST CHALLENGE WILL BE
DETERMINING CHANCES OF PRECIPITATION LATE TONIGHT INTO WEDNESDAY.
UPPER LEVEL FLOW IS QUASI-ZONAL FOR THE SHORT TERM. A NEARLY
STATIONARY SURFACE BOUNDARY IS LOCATED IN A ROUGHLY EAST-WEST
ORIENTATION. SATELLITE CONFIRMS A DEVELOPING CUMULUS FIELD ALONG THIS
BOUNDARY AND SHOULD EVENTUALLY BLOW UP INTO A BUSY THUNDERSTORM
SCENARIO IN SOUTHERN KANSAS AND POINTS SOUTH. IT LOOKS LIKE THIS
BOUNDARY IS FAR ENOUGH SOUTH FOR ALL OF THE THUNDERSTORM TO REMAIN
SOUTH OF THE CWA FROM THIS MECHANISM.
FOR TONIGHT...THE NAM HAS ADVERTISED FOR THE PAST COUPLE OF RUNS A
MID-LEVEL FRONTOGENETIC BAND SETTING UP LATE TONIGHT FROM 09Z TO 12Z
FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA. IT IS DIFFICULT TO TELL
WHERE THIS WILL EVENTUALLY SET UP...AND I CALCULATE THE NEED TO ADD
SOME SMALL CHANCES OF PRECIPITATION FOR THIS TIME PERIOD TO THE
ENTIRE CWA. WITH MUCAPES JUST HIGH ENOUGH TO PRODUCE THUNDER
ACROSS MOST OF THE CWA. A STRONG STORM IS CERTAINLY POSSIBLE IN
OUR FAR SOUTH WITH BETTER INSTABILITY AND DECENT SHEAR.
I INCREASED CHANCES OF PRECIPITATION FOR WEDNESDAY ACROSS THE CWA AS
THERE ARE MULTIPLE SOLUTIONS THAT INDICATE MEASURABLE PRECIPITATION
AS A SHORTWAVE TROUGH SWINGS IN. SREF SEVERE THUNDERSTORM PARAMETERS
INDICATE THAT A STRONG TO SEVERE THUNDERSTORM WILL BE POSSIBLE
ANYWHERE IN THE CWA...BUT SEEMS MORE LIKELY IN THE FAR SOUTHWEST
WHERE BETTER INSTABILITY EXISTS. TIMING OF THE WAVE SEEMS TO FAVOR
AFTERNOON FOR STRONGER THUNDERSTORMS.
LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERNS
WILL BE CHANCE FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT AND
THURSDAY AND ON AND OFF SUNDAY THROUGH TUESDAY.
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE THROUGH THE PLAINS
WEDNESDAY NIGHT AND MOVE OUT OF THE AREA ON THURSDAY. EXPECT SHOWERS
ACROSS THE AREA WEDNESDAY NIGHT. THE QUESTION WILL BE HOW MUCH
INSTABILITY THERE WILL BE TO CAUSE SOME THUNDERSTORMS. LATEST MODEL
RUNS SHOW SOME CAPE ACROSS THE SOUTHERN PART OF THE FORECAST AREA
DURING THE EVENING AND VERY LITTLE AFTER 06Z. THE MINIMAL
INSTABILITY CONTINUES INTO THURSDAY MORNING BUT BY AFTERNOON THERE
SHOULD BE LITTLE MORE THAN SHOWERS AROUND. THE UPPER LOW CONTINUES
TO MOVE TO THE EAST SO EXPECT THE PRECIPITATION TO COME TO AN END
DURING THE DAY THURSDAY. WILL CONTINUE TO HAVE SOME CLOUDS WITH THE
UPPER LOW SPINNING MOISTURE INTO THE AREA. TEMPERATURES WILL REMAIN
ON THE COOL SIDE FOR THURSDAY.
FOR THURSDAY NIGHT THROUGH SATURDAY NIGHT...THERE IS NORTHWEST FLOW
ACROSS THE REGION AND DESPITE A FEW VERY WEAK WAVES DRY CONDITIONS
SHOULD PREVAIL. TEMPERATURES WILL BE ON A WARMING TREND DURING THIS
TIME.
A STRONGER UPPER LEVEL WAVE WILL MOVE INTO THE AREA SUNDAY. A
SURFACE LOW DEVELOPS IN WESTERN KANSAS AND THERE IS A TROUGH TO THE
NORTH OF THE LOW. THERE COULD BE A FEW SHOWERS OR THUNDERSTORMS THAT
DEVELOP MAINLY IN THE AFTERNOON IN THE NORTHWEST PART OF THE
FORECAST AREA. BY SUNDAY NIGHT THE WAVE MOVES INTO THE AREA BETTER
AND THERE IS A SLIGHT CHANCE FOR SOME SHOWERS AND THUNDERSTORMS
SUNDAY NIGHT. FOR MONDAY THE UPPER WAVE MOVES OUT...BUT ANOTHER
STARTS TO MOVE INTO THE AREA MONDAY AFTERNOON.
AN UPPER LEVEL LOW MOVES INTO THE AREA FOR MONDAY NIGHT INTO
TUESDAY. THIS WILL BRING A BETTER CHANCE FOR THUNDERSTORMS FOR
MONDAY NIGHT INTO TUESDAY. AT THIS TIME STILL TOO EARLY TO TELL HOW
MUCH POTENTIAL FOR SEVERE THERE WILL BE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1107 PM CDT TUE MAY 29 2012
.UPDATE...RECENTLY COMPLETED A RELATIVELY MINOR UPDATE FOR THE
OVERNIGHT HOURS. PRIMARY CHANGE WAS TO PULL ALL MENTION OF
SHOWERS/STORMS BEFORE 09Z...AND ALTHOUGH KEPT AT LEAST A SLIGHT
CHANCE ALL AREAS AFTER 09Z...PULLED THUNDER MENTION FROM A HANDFUL
OF NORTHEAST/EASTERN COUNTIES. FOR THE EARLY PORTION OF THE
OVERNIGHT HOURS...A FEW ELEVATED STORMS WILL CONTINUE BLOSSOMING
ACROSS PARTS OF EAST CENTRAL/NORTHEAST KS...BUT SHOULD REMAIN AT
LEAST 50 MILES OR SO SOUTHEAST OF THE EXTREME SOUTHEASTERN CWA.
THIS CONVECTION SEEMS BEST TIED TO THETA-E ADVECTION AROUND THE
700MB LEVEL...ALONG THE FAR NORTHERN EDGE OF THE NORTHWARD-
RETURNING INSTABILITY AXIS. BETTER CHANCES FOR STORMS WITHIN THE
CWA WILL HAVE TO WAIT UNTIL VERY LATE TONIGHT INTO WEDNESDAY
MORNING...WHEN MID LEVEL FRONTOGENESIS/SATURATION INCREASES FROM
THE NORTHWEST...AND ANOTHER SURGE OF THETA-E ADVECTION IN THE
850-700MB LAYER TAKES PLACE...BUT THIS TIME AIMED MUCH MORE SO
INTO AT LEAST SOUTHWEST PARTS OF THE CWA. MODEL QPF IS ALL OVER
THE PLACE...WITH THE LATEST HRRR RUNS BARELY BRINGING ANYTHING
INTO THE CWA BEFORE SUNRISE...WHILE BOTH THE 00Z NAM/GFS AT LEAST
BRING SOME ACTIVITY INTO THE SOUTHWEST COUNTIES. ALTHOUGH NOT
NECESSARILY ANTICIPATING A LATE NIGHT/EARLY MORNING SEVERE
THREAT...INSERTED PENNY SIZE HAIL MENTION INTO THE HWO TO ACCOUNT
FOR THE NAM DEPICTION OF 500-1000+ J/KG MUCAPE INTO
SOUTHERN/SOUTHWEST ZONES. AS MENTIONED BEFORE...PULLED ALL
OVERNIGHT THUNDER MENTION FROM NORTHEAST ZONES AS SUFFICIENT
ELEVATED INSTABILITY SHOULD STRUGGLE TO REACH NORTHEAST OF AN ORD-
GENEVA LINE. MADE VERY LITTLE IF ANY CHANGE TO OVERNIGHT LOW
TEMPS...BUT NUDGED DOWN 1 DEGREE OR SO SOME AREAS BASED ON LATEST
HOURLY GFS LAMP GUIDANCE...AIMING FOR A RANGE FROM MID-UPPER 40S
FAR NORTH...TO MID 50S IN KS ZONES.
&&
.PREV DISCUSSION... /ISSUED 613 PM CDT TUE MAY 29 2012/
AVIATION...00Z KGRI TAF. ALTHOUGH CONFIDENCE IS FAIRLY
HIGH THAT THE VAST MAJORITY OF THE PERIOD WILL FEATURE VFR
CATEGORY CEILING/VISIBILITY...PASSING SHOWERS AND THUNDERSTORMS
DURING THE DAY WEDNESDAY COULD BRIEFLY RESULT IN MVFR CONDITIONS.
FOR THE TIME BEING...WILL OMIT THIS MVFR POSSIBILITY FROM THE
TAF...BUT WILL CARRY A LOW-END VFR CEILING THROUGH MUCH OF THE
DAY. STARTING WITH THIS EVENING/OVERNIGHT...MOSTLY CLEAR SKIES AND
LIGHT EASTERLY BREEZES WILL PREVAIL...WITH A FAIRLY SOLID MID
LEVEL CLOUD DECK SLATED TO ARRIVE BY SUNRISE. ON WEDNESDAY...MORE
THAN ONE ROUND OF SHOWERS/STORMS IS POSSIBLE...BUT PRECIPITATION
IS UNLIKELY TO BE NON-STOP. AS A RESULT...OPTED TO GO WITH PROB30
GROUPS TO COVER THE PRECIPITATION CHANCES FOR NOW...AND WILL DEFER
TO LATER SHIFTS TO ADD MORE DETAILED PREVAILING/TEMPO GROUPS AS
THE RAIN EVENT DRAWS CLOSER. IT APPEARS ANY STORMS THAT MIGHT
AFFECT KGRI ON WEDNESDAY SHOULD REMAIN BELOW SEVERE
LIMITS...ALTHOUGH SMALL HAIL AND GUSTY WINDS ARE NOT COMPLETELY
OUT OF THE QUESTION.
PREV DISCUSSION... /ISSUED 344 PM CDT TUE MAY 29 2012/
SHORT TERM...TONIGHT AND WEDNESDAY. BIGGEST CHALLENGE WILL BE
DETERMINING CHANCES OF PRECIPITATION LATE TONIGHT INTO WEDNESDAY.
UPPER LEVEL FLOW IS QUASI-ZONAL FOR THE SHORT TERM. A NEARLY
STATIONARY SURFACE BOUNDARY IS LOCATED IN A ROUGHLY EAST-WEST
ORIENTATION. SATELLITE CONFIRMS A DEVELOPING CUMULUS FIELD ALONG THIS
BOUNDARY AND SHOULD EVENTUALLY BLOW UP INTO A BUSY THUNDERSTORM
SCENARIO IN SOUTHERN KANSAS AND POINTS SOUTH. IT LOOKS LIKE THIS
BOUNDARY IS FAR ENOUGH SOUTH FOR ALL OF THE THUNDERSTORM TO REMAIN
SOUTH OF THE CWA FROM THIS MECHANISM.
FOR TONIGHT...THE NAM HAS ADVERTISED FOR THE PAST COUPLE OF RUNS A
MID-LEVEL FRONTOGENETIC BAND SETTING UP LATE TONIGHT FROM 09Z TO 12Z
FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA. IT IS DIFFICULT TO TELL
WHERE THIS WILL EVENTUALLY SET UP...AND I CALCULATE THE NEED TO ADD
SOME SMALL CHANCES OF PRECIPITATION FOR THIS TIME PERIOD TO THE
ENTIRE CWA. WITH MUCAPES JUST HIGH ENOUGH TO PRODUCE THUNDER
ACROSS MOST OF THE CWA. A STRONG STORM IS CERTAINLY POSSIBLE IN
OUR FAR SOUTH WITH BETTER INSTABILITY AND DECENT SHEAR.
I INCREASED CHANCES OF PRECIPITATION FOR WEDNESDAY ACROSS THE CWA AS
THERE ARE MULTIPLE SOLUTIONS THAT INDICATE MEASURABLE PRECIPITATION
AS A SHORTWAVE TROUGH SWINGS IN. SREF SEVERE THUNDERSTORM PARAMETERS
INDICATE THAT A STRONG TO SEVERE THUNDERSTORM WILL BE POSSIBLE
ANYWHERE IN THE CWA...BUT SEEMS MORE LIKELY IN THE FAR SOUTHWEST
WHERE BETTER INSTABILITY EXISTS. TIMING OF THE WAVE SEEMS TO FAVOR
AFTERNOON FOR STRONGER THUNDERSTORMS.
LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERNS
WILL BE CHANCE FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT AND
THURSDAY AND ON AND OFF SUNDAY THROUGH TUESDAY.
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE THROUGH THE PLAINS
WEDNESDAY NIGHT AND MOVE OUT OF THE AREA ON THURSDAY. EXPECT SHOWERS
ACROSS THE AREA WEDNESDAY NIGHT. THE QUESTION WILL BE HOW MUCH
INSTABILITY THERE WILL BE TO CAUSE SOME THUNDERSTORMS. LATEST MODEL
RUNS SHOW SOME CAPE ACROSS THE SOUTHERN PART OF THE FORECAST AREA
DURING THE EVENING AND VERY LITTLE AFTER 06Z. THE MINIMAL
INSTABILITY CONTINUES INTO THURSDAY MORNING BUT BY AFTERNOON THERE
SHOULD BE LITTLE MORE THAN SHOWERS AROUND. THE UPPER LOW CONTINUES
TO MOVE TO THE EAST SO EXPECT THE PRECIPITATION TO COME TO AN END
DURING THE DAY THURSDAY. WILL CONTINUE TO HAVE SOME CLOUDS WITH THE
UPPER LOW SPINNING MOISTURE INTO THE AREA. TEMPERATURES WILL REMAIN
ON THE COOL SIDE FOR THURSDAY.
FOR THURSDAY NIGHT THROUGH SATURDAY NIGHT...THERE IS NORTHWEST FLOW
ACROSS THE REGION AND DESPITE A FEW VERY WEAK WAVES DRY CONDITIONS
SHOULD PREVAIL. TEMPERATURES WILL BE ON A WARMING TREND DURING THIS
TIME.
A STRONGER UPPER LEVEL WAVE WILL MOVE INTO THE AREA SUNDAY. A
SURFACE LOW DEVELOPS IN WESTERN KANSAS AND THERE IS A TROUGH TO THE
NORTH OF THE LOW. THERE COULD BE A FEW SHOWERS OR THUNDERSTORMS THAT
DEVELOP MAINLY IN THE AFTERNOON IN THE NORTHWEST PART OF THE
FORECAST AREA. BY SUNDAY NIGHT THE WAVE MOVES INTO THE AREA BETTER
AND THERE IS A SLIGHT CHANCE FOR SOME SHOWERS AND THUNDERSTORMS
SUNDAY NIGHT. FOR MONDAY THE UPPER WAVE MOVES OUT...BUT ANOTHER
STARTS TO MOVE INTO THE AREA MONDAY AFTERNOON.
AN UPPER LEVEL LOW MOVES INTO THE AREA FOR MONDAY NIGHT INTO
TUESDAY. THIS WILL BRING A BETTER CHANCE FOR THUNDERSTORMS FOR
MONDAY NIGHT INTO TUESDAY. AT THIS TIME STILL TOO EARLY TO TELL HOW
MUCH POTENTIAL FOR SEVERE THERE WILL BE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE/AVIATION...PFANNKUCH
SHORT TERM...HEINLEIN
LONG TERM...JCB
AREA FORECAST DISCUSSION
NWS BUFFALO NY
740 PM EDT THU MAY 31 2012
.SYNOPSIS...
HIGH PRESSURE THAT BROUGHT SOME SUNSHINE AND COOLER TEMPERATURES TO
OUR AREA THIS AFTERNOON WILL SLIDE TO THE NEW ENGLAND COAST TONIGHT.
LOW PRESSURE LIFTING OUT OF THE OHIO VALLEY TONIGHT WILL THEN SPREAD
SOME MUCH NEEDED RAIN ACROSS THE REGION ON FRIDAY. SOMEWHAT
UNSETTLED CONDITIONS WILL REMAIN IN PLACE FOR THE UPCOMING
WEEKEND...ALTHOUGH MUCH OF THE TIME SHOULD BE RAIN FREE.
&&
.NEAR TERM /THROUGH FRIDAY/...
FOLLOWING A BRIEF CLEARING THIS EVENING...CLOUDS WILL INCREASE
FROM WEST TO EAST AS THE NEXT SYSTEM APPROACHES. THE CULPRIT WILL
BE LOW PRESSURE DEVELOPING ACROSS OHIO TONIGHT...WHICH IS FORECAST TO
STRENGTHEN AS IT TRACKS NORTHWARD ACROSS LAKE ERIE AND LAKE HURON
LATE FRIDAY. THE LOWS DEVELOPMENT WILL BE DRIVEN BY ENERGY
ALOFT...WITH A CLOSED 500 MB LOW APPROACHING FROM THE MIDWEST
DURING THIS TIME-FRAME.
AHEAD OF THE SURFACE LOW...AN ANOMALOUSLY STRONG (4 STD) SOUTHERLY
LOW LEVEL JET WILL MOVE NORTH TOWARD WESTERN NEW YORK LATE
TONIGHT. THIS WILL CAUSE RAIN TO DEVELOP TONIGHT. 18Z RUNS OF THE
NAM/GFS AND THE HRRR HAVE TRENDED A TAD SLOWER WITH THIS...WITH
RAIN LIKELY TO REACH FAR WESTERN NEW YORK AROUND DAYBREAK. WARM
AIR ADVECTION WILL BE WEAKER TO THE EAST...SINCE IT IS FURTHER
FROM THE UPPER LOW.
THE POTENT LOW LEVEL JET WILL LIFT ACROSS WESTERN NEW YORK ON
FRIDAY MORNING AND EARLY AFTERNOON. THERE MAY BE A BRIEF BREAK IN
THE RAIN DURING THE DAY FRIDAY...BUT RAIN SHOULD RETURN LATE
AFTERNOON AND INTO FRIDAY EVENING AS THE OCCLUDED FRONT SLOWLY
CROSSES THE REGION FROM WEST TO EAST. IT IS THIS FEATURE WHICH IS
LIKELY TO BRING THE HEAVIEST RAIN. IN ADDITION TO THE STEADY
RAIN...THE LATEST STABILITY INDICES SUGGESTS THAT THERE WILL BE A
CHANCE FOR SOME EMBEDDED THUNDERSTORMS LATER IN THE AFTERNOON AND
EVENING.
HPC`S LATEST QPF GUIDANCE FOR FRIDAY INDICATES A POTENTIAL FOR A
LITTLE OVER AN INCH OF RAIN ACROSS WESTERN NEW YORK AND THE GENESEE
VALLEY...WITH ABOUT ONE THIRD TO THREE QUARTERS OF AN INCH FARTHER
TO THE EAST. DUE TO THE RECENT DRY TREND...THIS RAINFALL SHOULD NOT
CAUSE SIGNIFICANT PROBLEMS...BUT WE WILL HAVE TO KEEP AN EYE ON THE
POTENTIAL FOR HIGHER AMOUNTS IF CONVECTION DOES DEVELOP.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
COLD FRONT STILL SCHEDULED TO CROSS THE REGION FRIDAY NIGHT. AHEAD
OF THE FRONT...WIDESPREAD RAIN AND EMBEDDED THUNDERSTORMS WILL BE
ONGOING. THE UPPER LEVEL TROUGH WILL BE TAKING ON A NEGATIVE TILT
ALLOWING FAVORABLE LOW LEVEL JET DYNAMICS AND IMPRESSIVE MOISTURE
TRANSPORT TO BECOME FOCUSED ALONG AND AHEAD OF THE FRONT ACROSS THE
GENESEE VALLEY/FINGER LAKES FRIDAY EVENING...THEN INTO THE EASTERN
LAKE ONTARIO REGION AFTER MIDNIGHT. RAINFALL AMOUNTS IN EXCESS OF AN
INCH ARE LIKELY IN THESE AREAS. DRY SLOT WILL FOLLOW THE FRONT
WITH A SHARP DECREASE IN OVERALL PRECIPITATION INTENSITY AND
COVERAGE...WITH ONLY SCATTERED COVERAGE AT BEST WITHIN THIS AREA.
DRYING MAY EVEN BE EXTENSIVE ENOUGH TO BRING A BRIEF BIT OF
CLEARING.
GOOD PORTION OF THE AREA LOOKS TO BE UNDER THE INFLUENCE OF THE DRY
SLOT SATURDAY MORNING...BEFORE WRAP AROUND MOISTURE SLOWLY WORKS
INTO THE REGION FROM THE WEST. FOR THE MOST PART...SATURDAY MAY
WIND UP PRECIPITATION FREE FOR MANY AREAS WITH THE BETTER CHANCES
ACROSS THE FAR WEST...BUT PROBABLY NOT LOOKING AT A WASH OUT. COLD
AIR ADVECTION WILL BRING A COOL DAY WITH MOST HIGHS IN THE MID
60S.
MID LEVEL COLD POOL ASSOCIATED WITH THE CLOSED CIRCULATION DROPPING
SOUTHEAST FROM CANADA WILL BRING INCREASING CHANCE FOR SHOWERS
SUNDAY. MOST OF THE ACTIVITY LOOKS TO BE DIURNALLY DRIVEN...AS
MODEL SOUNDINGS SUGGESTING STEEPENING MID LEVEL LAPSE RATES BY
AFTERNOON. ANOTHER COOL DAY WITH MOST HIGHS IN THE MID TO UPPER
60S...ALTHOUGH COULD BE COOLER IF PRECIPITATION DEVELOPS EARLY
ENOUGH IN THE DAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LATEST DETERMINISTIC MODEL AND ENSEMBLE DATA CONTINUING TO SUGGEST
LITTLE IN THE WAY OF A PATTERN CHANGE DURING THE PERIOD...WITH
GOOD AGREEMENT BETWEEN THE GFS/CANADIAN/ECMWF. THE LARGE SCALE
UPPER LEVEL FLOW IS CONTINUING TO SIGNAL THE NAO BECOMING HIGHLY
NEGATIVE DURING THE PERIOD...WITH THE FORMATION OF AN OMEGA BLOCK
ACROSS THE NORTH ATLANTIC. THIS WILL RESULT IN THE CONTINUATION OF
THE DEEP UPPER TROUGH OVER NEW ENGLAND AND THE CANADIAN MARITIMES.
THIS PATTERN WILL FAVOR BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD...WITH THE CHANCE OF MAINLY DIURNALLY DRIVEN SHOWERS ON THE
WESTERN SIDE OF THE CYCLONIC FLOW ALOFT.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
TONIGHT SHOULD START OFF VFR AT ALL LOCATIONS...WITH MOSTLY CLEAR
SKIES EVENTUALLY FORECAST TO GIVE WAY TO MID AND HIGH CLOUDS
APPROACHING FROM THE WEST. SOME RAIN WILL BREAK OUT AFTER ABOUT
09Z OVER THE FAR WESTERN COUNTIES. THERE WILL ALSO BE THE
LIKELIHOOD OF SOME LOW LEVEL WIND SHEAR LATE TONIGHT ACROSS
WESTERN NEW YORK AS A LOW LEVEL JET...AVERAGING 35 TO 40 KNOTS
LIFTS NORTH FROM THE OHIO VALLEY.
ON FRIDAY...AN AREA OF RAIN WILL SPREAD EAST ACROSS THE
AREA...WITH THIS LIKELY TO BRING A PERIOD OF MVFR CONDITIONS.
DESPITE THE MOISTURE...THE SE FLOW SHOULD TEND TO DOWNSLOPE AT
BUF/IAG/ROC/ART...WITH LOWEST CIGS LIKELY AT JHW WHERE SE WINDS
HAVE LESS OF A DRYING AFFECT.
A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST FRIDAY
AFTERNOON...POSSIBLY BRINGING A PERIOD OF HEAVY RAIN TO
BUF/IAG/JHW BEFORE 00Z. EMBEDDED THUNDERSTORMS ARE ALSO
POSSIBLE...WITH IFR/MVFR CONDITIONS LIKELY DUE TO LOWERING CIGS AND
VSBY. CONDITIONS MAY BRIEFLY LOWER TO IFR OR LOWER FRIDAY
EVENING...AS THE SURFACE LOW PASSES TO THE WEST OF THE REGION.
OUTLOOK...
SATURDAY...VFR WITH A CHANCE OF SHOWERS.
SUNDAY...VFR/MVFR WITH CHANCE OF SHOWERS.
MONDAY...MAINLY VFR WITH CHANCE OF SHOWERS.
&&
.MARINE...
LOW PRESSURE WILL MOVE NORTH TOWARD THE OHIO VALLEY TONIGHT...THEN
LIFT JUST NORTH OF LAKE ERIE ON FRIDAY. THE INCREASING PRESSURE
GRADIENT AHEAD OF THE LOW WILL CAUSE EASTERLY WINDS TO PICK UP ON
LAKE ERIE AND THE WESTERN END OF LAKE ONTARIO LATER TONIGHT. WHILE
THE HIGHEST WAVES ON LAKE ERIE WILL BE OVER THE CANADIAN
WATERS...THE WINDS WILL SATISFY THE CRITERIA NEEDED FOR A SMALL
CRAFT ADVISORY.
AS THE LOW LIFTS WEST OF LAKES ERIE AND ONTARIO ON FRIDAY...WINDS
AND WAVES WILL SUBSIDE A BIT ON LAKE ERIE...BUT MODEST EAST TO
SOUTHEAST WINDS WILL CONTINUE TO IMPACT LAKE ONTARIO THROUGH THE
THE DAY.
INCREASING SOUTHWEST WINDS WILL IMPACT BOTH LAKES ON SATURDAY AS THE
LOW CONTINUES TO LIFT NORTH ACROSS SOUTHERN ONTARIO.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT FRIDAY FOR LEZ040-
041.
SMALL CRAFT ADVISORY FROM 11 AM FRIDAY TO 5 AM EDT
SATURDAY FOR LOZ043-044.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 2 AM EDT SATURDAY
FOR LOZ042.
&&
$$
SYNOPSIS...TJP
NEAR TERM...APFFEL/TJP
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...APFFEL
MARINE...TJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
153 PM EDT WED MAY 30 2012
.SYNOPSIS...
COOLER AND DRIER AIR HAS ENTERED THE REGION...IN THE WAKE OF THE
STORMY COLD FRONT THAT PASSED THROUGH LATE TUESDAY. HOWEVER...A
SECONDARY FRONT WILL MOVE THROUGH THIS AFTERNOON...WITH SCATTERED
SHOWERS AND A CHANCE OF THUNDER. BEST CHANCES WILL BE FROM THE
SOUTHERN TIER AND CATSKILLS OF NEW YORK...INTO NORTHEAST
PENNSYLVANIA. DRY WEATHER AND EVEN COOLER AIR WILL FOLLOW TONIGHT
THROUGH THURSDAY NIGHT. A WETTER PERIOD IS EXPECTED WITH A SLOW
MOVING SYSTEM FRIDAY THROUGH A GOOD PART OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
130 PM UPDATE...
AS EXPECTED...SECONDARY FRONT HAS NOT HAD ANY PROBLEM DEVELOPING
SOME CONVECTION...ALBEIT OF LIMITED COVERAGE. UNLIKE
YESTERDAY...UPPER LEVEL TRIGGER IS ABSENT...BUT WEAK LOW LEVEL
CONVERGENCE ALONG SECONDARY FRONT AND DIURNAL HEATING HAS BEEN
ENOUGH TO YIELD CONVECTION.
LATEST NAM AND RUC SOUNDINGS SHOW SEVERAL HUNDRED CAPE...AND
ADEQUATE PRECIPITABLE WATER /ROUGHLY AN INCH/ FOR ISOLATED TO
SCATTERED COVERAGE OF SHOWERS WITH CHANCE OF THUNDER. CURRENT
DEWPOINTS FAVOR THE INSTABILITY OF NAM/RUC SOUNDINGS...AND ABILITY
TO BREAK CAP...VERSUS GFS SOUNDINGS. COMPLETELY DIFFERENT FROM THE
SEVERE ENVIRONMENT OF YESTERDAY...BUT ENTRAINMENT OF DRY AIR AND
SOME SPEED SHEAR...COULD YIELD SOME GUSTINESS IN THE
SHOWERS/THUNDER. TIMING OF THINGS WILL KEEP NORTHWESTERN ZONES
DRY...YET BETTER COVERAGE THE FARTHER SOUTH AND EAST YOU GO. BEST
CHANCES WILL BE SOUTHEAST OF A TOWANDA-BINGHAMTON-ONEONTA LINE.
DIURNALLY DEPENDENT CONVECTION WILL QUICKLY END THIS
EVENING...LEAVING US A DRY AND COOLER NIGHT WITH VARIABLE
CLOUDS...AND LOWS IN THE UPPER 40S TO MID 50S.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
A QUIET PERIOD SETS UP TONIGHT THROUGH THURSDAY NIGHT, AS WE ARE
IN BETWEEN STORM SYSTEMS. LATE THURSDAY NIGHT, A LOW PRESSURE
STORM SYSTEM WILL MOVE OUT OF THE OHIO VALLEY TOWARD LAKE ERIE.
MODELS ARE IN PRETTY GOOD AGREEMENT REGARDING THE POSITION OF THE
LOW. HOWEVER THERE IS A LARGE DISCREPANCY CONCERNING THE EASTWARD
EXTENT OF THE PRECIPITATION SHIELD.
GFS AND EURO KEEP A STRONGER PRESENCE OF AN EXITING ANTICYCLONE
OVER NORTHEASTERN NY. NAM IS MUCH WEAKER WITH THE HIGH, AND HAS
THIS FEATURE PLACED FURTHER EASTWARD.
NAM APPEARS TOO AGGRESSIVE WITH THE EASTWARD EXTENT OF THE WARM
FRONTAL PRECIPITATION. GFS MAY BE UNREALISTICALLY KEEPING THINGS
TOO FAR WEST. EURO LOOKS LIKE A REALISTIC COMPROMISE. WE HAVE
PULLED BACK ON THE EASTERN FA GUIDANCE POPS TO REFLECT GREATER
UNCERTAINTY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
HIGHER CONFIDENCE FCST TODAY WITH THE BIG UPR LOW AS THE LONG
RANGE MODELS COME INTO REMARKABLY GOOD AGREEMENT WITH THE PSN OF
THE LOW...AND TIMING OF WVS ROTATING THRU. VERTICALLY STACKED LOW
LIFTS NWRD TO A PSN NORTH OF GEORGIAN BAY EARLY SUN. THIS KEEPS
THE CORE OF DEEP MOISTURE NORTH OF THE AREA BUT DOES KEEP US IN A
NW FLOW OF COOL AIR. H8 TEMPS HOVER ARND 8C AS WV/S DROP THRU IN
THE NW FLOW. SHWRS WILL BE PSBL NEARLY ANYTIME...BUT WILL PEAK
DURING AFTN HTG...AND WITH THE LRGR WVS. INDIVIDUAL WV/S DFCLT TO
TIME...BUT WV/S LOOK TO PASS LTR SUN...EARLY MON...AND ESP ON TUE
AS THE UPR LOW BEGINS TO MVE SOUTH AND EAST AND THE COOL POOL
ALOFT MVES CLSR.
GNRLY FLWD HPC GUID FOR THE FCST...WHICH WAS CLOSE TO MEX POPS AND
TEMPS LEADING TO A HIER CONFIDENCE IN THE NUMBERS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SFC TROF PASSING THRU THE FCST AREA ATTM WITH WEAK CONV FIRING
AHD. PSN OF THE TROF WILL PUT MOST OR ALL OF THE CONV EAST OF THE
TAF SITES...SO WILL NOT INCLUDE ANY MENTION IN THE FCST. DRIER AIR
MVG IN BHD THE TROF WILL KEEP THE AREA IN VFR THRU THE TAF PD.
XCPTN MAY BE AT ELM WHERE THE DEEP VLY MAY ALLOW SOME POOLONG OF
COOL AND DAMP AIR ALLOWING FOR SOME MVFR LATE. ANY FOG WILL
QUICKLY ERODE WITH GOOD MIXING AND MORE DRY AIR ON THU.
.OUTLOOK...
THU AFTN TO FRI MRNG...MAINLY VFR. WIDESPREAD LATE NIGHT FOG NOT
EXPECTED.
FRI AFT TO SAT MRNG...MVFR/IFR IN RAIN.
SAT AFTN THRU MON...VFR...WITH MVFR IN OCCASIONAL SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DGM
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
132 PM EDT WED MAY 30 2012
.SYNOPSIS...
COOLER AND DRIER AIR HAS ENTERED THE REGION...IN THE WAKE OF THE
STORMY COLD FRONT THAT PASSED THROUGH LATE TUESDAY. HOWEVER...A
SECONDARY FRONT WILL MOVE THROUGH THIS AFTERNOON...WITH SCATTERED
SHOWERS AND A CHANCE OF THUNDER. BEST CHANCES WILL BE FROM THE
SOUTHERN TIER AND CATSKILLS OF NEW YORK...INTO NORTHEAST
PENNSYLVANIA. DRY WEATHER AND EVEN COOLER TEMPERATURES WILL FOLLOW
TONIGHT THROUGH THURSDAY NIGHT. A WETTER PERIOD IS EXPECTED WITH A
SLOW MOVING SYSTEM FRIDAY THROUGH A GOOD PART OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
130 PM UPDATE...
AS EXPECTED...SECONDARY FRONT HAS NOT HAD ANY PROBLEM DEVELOPING
SOME CONVECTION...ALBEIT OF LIMITED COVERAGE. UNLIKE
YESTERDAY...UPPER LEVEL TRIGGER IS ABSENT...BUT WEAK LOW LEVEL
CONVERGENCE ALONG SECONDARY FRONT AND DIURNAL HEATING HAS BEEN
ENOUGH TO YIELD CONVECTION.
LATEST NAM AND RUC SOUNDINGS SHOW SEVERAL HUNDRED CAPE...AND
ADEQUATE PRECIPITABLE WATER /ROUGHLY AN INCH/ FOR ISOLATED TO
SCATTERED COVERAGE OF SHOWERS WITH CHANCE OF THUNDER. CURRENT
DEWPOINTS FAVOR THE INSTABILITY OF NAM/RUC SOUNDINGS...AND ABILITY
TO BREAK CAP...VERSUS GFS SOUNDINGS. COMPLETELY DIFFERENT FROM THE
SEVERE ENVIRONMENT OF YESTERDAY...BUT ENTRAINMENT OF DRY AIR AND
SOME SPEED SHEAR...COULD YIELD SOME GUSTINESS IN THE
SHOWERS/THUNDER. TIMING OF THINGS WILL KEEP NORTHWESTERN ZONES
DRY...YET BETTER COVERAGE THE FARTHER SOUTH AND EAST YOU GO. BEST
CHANCES WILL BE SOUTHEAST OF A TOWANDA-BINGHAMTON-ONEONTA LINE.
DIURNALLY DEPENDENT CONVECTION WILL QUICKLY END THIS
EVENING...LEAVING US A DRY AND COOLER NIGHT WITH VARIABLE
CLOUDS...AND LOWS IN THE UPPER 40S TO MID 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A QUIET PERIOD SETS UP TONIGHT THROUGH THURSDAY NIGHT, AS WE ARE
IN BETWEEN STORM SYSTEMS. LATE THURSDAY NIGHT, A LOW PRESSURE
STORM SYSTEM WILL MOVE OUT OF THE OHIO VALLEY TOWARD LAKE ERIE.
MODELS ARE IN PRETTY GOOD AGREEMENT REGARDING THE POSITION OF THE
LOW. HOWEVER THERE IS A LARGE DISCREPANCY CONCERNING THE EASTWARD
EXTENT OF THE PRECIPITATION SHIELD.
GFS AND EURO KEEP A STRONGER PRESENCE OF AN EXITING ANTICYCLONE
OVER NORTHEASTERN NY. NAM IS MUCH WEAKER WITH THE HIGH, AND HAS
THIS FEATURE PLACED FURTHER EASTWARD.
NAM APPEARS TOO AGGRESSIVE WITH THE EASTWARD EXTENT OF THE WARM
FRONTAL PRECIPITATION. GFS MAY BE UNREALISTICALLY KEEPING THINGS
TOO FAR WEST. EURO LOOKS LIKE A REALISTIC COMPROMISE. WE HAVE
PULLED BACK ON THE EASTERN FA GUIDANCE POPS TO REFLECT GREATER
UNCERTAINTY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
2 AM UPDATE...
NO BIG CHANGES. UPPER LEVEL TROF MOVES THROUGH THE AREA EARLY IN
THE PERIOD BUT REMAINS OVER EASTERN NEW ENGLAND STARTING MONDAY.
STEADY SOAKING RAIN FRIDAY NIGHT TO SATURDAY NIGHT THEN IN
NORTHWEST FLOW WITH SOME SHOWERS AND SLIGHTLY COLDER TEMPERATURES
THAN NORMAL. WITH TEMPERATURES WELL ABOVE NORMAL NOW THIS AIR WILL
FEEL COLD.
PREVIOUS DISCUSSION...
XTNDD PD FEATURES A LRG UPR LOW BRINGING UNSETTLED WX TO THE FCST
AREA. SFC FNTL BNDRY PASSES LATE FRI OR EARLY SAT USHERING IN
COOLER AIR AS THE UPR LOW SETTLES OVER THE ERN GREAT LAKES. AFT A
BRIEF PD OF DRY WX DIRECTLY BHD THE FNT...MOISTURE ASSOCIATED WITH
THE UPR LOW ROTATES INTO THE FCST AREA AND LINGERS THRU MUCH OF
THE PD. DAYTIME TEMPS WILL BE BLO NRML WITH H8 TEMPS TO ARND 8C.
LOW BEGINS TO LIFT LATE IN THE PD...BUT WAA MAY GENERATE A FEW
SHWRS THRU MON.
WITH ONGOING SVR WX...RELIED ON HPC GUID FOR MUCH OF THE XTNDD
PD...WITH ONLY A FEW MINOR ADJUSTMENTS.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
630 AM UPDATE...
MOST SITES VFR TODAY AND TONIGHT. ELM HAS DENSE FOG NOW AND VLIFR
FOG NOW WHICH SHOULD LIFT BY 14Z. TONIGHT ELM WILL HAVE MVFR VSBY
FOG STARTING AROUND 5Z. DRIER AIR COMING IN SO DENSE FOG NOT AS
LIKELY AS THIS MORNING. BGM AND ITH HAVE MVFR VSBYS NOW WHICH
SHOULD BECOME VFR AROUND 12Z.
TODAY A FEW SHOWERS POSSIBLE BUT NOT ENOUGH CONFIDENCE THAT ANY
ONE SITE WILL HAVE SHOWERS...TO PUT IT IN NOW. CIGS WILL STAY VFR
WITH DECREASING LOW LEVEL MOISTURE.
LIGHT AND VARIABLE TO CALM WINDS BECOMING WEST AND INCREASING TO
5 TO 10 KTS. TONIGHT AGAIN LIGHT AND VARIABLE.
.OUTLOOK...
THURSDAY TO FRIDAY MORNING...MAINLY VFR. WIDESPREAD LATE NIGHT
FOG NOT EXPECTED.
FRIDAY AFTERNOON TO SUNDAY...MVFR IN OCCASIONAL SHOWERS. FRIDAY
NIGHT STEADY RAIN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DGM/TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1028 AM EDT WED MAY 30 2012
.SYNOPSIS...
COOLER AND DRIER AIR HAS ENTERED THE REGION...IN THE WAKE OF THE
STORMY COLD FRONT THAT PASSED THROUGH LATE TUESDAY. HOWEVER...A
SECONDARY FRONT WILL MOVE THROUGH TODAY...WITH SCATTERED SHOWERS
AND A CHANCE OF THUNDER. BEST CHANCES WILL BE FROM THE SOUTHERN
TIER AND CATSKILLS OF NEW YORK...INTO NORTHEAST PENNSYLVANIA. DRY
WEATHER AND EVEN COOLER TEMPERATURES WILL FOLLOW TONIGHT THROUGH
THURSDAY NIGHT. A WETTER PERIOD IS EXPECTED WITH A SLOW MOVING
SYSTEM FRIDAY THROUGH A GOOD PART OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1015 AM UPDATE...
MOST OF THE LATEST HIGHER RESOLUTION MODELS SUGGEST THAT THE
SECONDARY FRONT SHOULD HAVE NO PROBLEM DEVELOPING SOME
CONVECTION...ALBEIT OF LIMITED COVERAGE. UNLIKE YESTERDAY...UPPER
LEVEL TRIGGER WILL BE ABSENT...BUT CONFIDENCE HAS INCREASED THAT
WEAK LOW LEVEL CONVERGENCE ALONG SECONDARY FRONT AND DIURNAL
HEATING FROM INCREASING SUNSHINE NOW OCCURRING...SHOULD BE ENOUGH
TO YIELD CONVECTION. FORECAST HAS BEEN ADJUSTED ACCORDINGLY.
LATEST NAM AND RUC SOUNDINGS SHOW SEVERAL HUNDRED CAPE...AND
ADEQUATE PRECIPITABLE WATER /ROUGHLY AN INCH/ FOR ISOLATED TO
SCATTERED COVERAGE OF SHOWERS WITH CHANCE OF THUNDER. CURRENT
DEWPOINTS FAVOR THE INSTABILITY OF NAM/RUC SOUNDINGS...AND ABILITY
TO BREAK CAP...VERSUS GFS SOUNDINGS. COMPLETELY DIFFERENT FROM THE
SEVERE ENVIRONMENT OF YESTERDAY...BUT ENTRAINMENT OF DRY AIR AND
SOME SPEED SHEAR...COULD YIELD SOME GUSTINESS IN THE
SHOWERS/THUNDER. TIMING OF THINGS WILL KEEP NORTHWESTERN ZONES
DRY...YET BETTER COVERAGE THE FARTHER SOUTH AND EAST YOU GO. BEST
CHANCES WILL BE SOUTHEAST OF A TOWANDA-BINGHAMTON-ONEONTA LINE.
PREVIOUS DISCUSSION...
A SECONDARY COLD FRONT WILL SLOWLY PUSH THROUGH MOIST AIR OVER THE
SOUTHEASTERN FORECAST AREA. LIFT IS WEAK, AND INSTABILITY WILL NOT
BE COMPARABLE TO PREVIOUS 24H. HOWEVER THE ATMOSPHERE SHOULD
SUPPORT ISOLATED CONVECTION IN THIS REGION DURING THE AFTERNOON
HOURS.
TEMPERATURES WILL TOP OUT BETWEEN 76F AND 81F THIS AFTERNOON.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A QUIET PERIOD SETS UP TONIGHT THROUGH THURSDAY NIGHT, AS WE ARE
IN BETWEEN STORM SYSTEMS. LATE THURSDAY NIGHT, A LOW PRESSURE
STORM SYSTEM WILL MOVE OUT OF THE OHIO VALLEY TOWARD LAKE ERIE.
MODELS ARE IN PRETTY GOOD AGREEMENT REGARDING THE POSITION OF THE
LOW. HOWEVER THERE IS A LARGE DISCREPANCY CONCERNING THE EASTWARD
EXTENT OF THE PRECIPITATION SHIELD.
GFS AND EURO KEEP A STRONGER PRESENCE OF AN EXITING ANTICYCLONE
OVER NORTHEASTERN NY. NAM IS MUCH WEAKER WITH THE HIGH, AND HAS
THIS FEATURE PLACED FURTHER EASTWARD.
NAM APPEARS TOO AGGRESSIVE WITH THE EASTWARD EXTENT OF THE WARM
FRONTAL PRECIPITATION. GFS MAY BE UNREALISTICALLY KEEPING THINGS
TOO FAR WEST. EURO LOOKS LIKE A REALISTIC COMPROMISE. WE HAVE
PULLED BACK ON THE EASTERN FA GUIDANCE POPS TO REFLECT GREATER
UNCERTAINTY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
2 AM UPDATE...
NO BIG CHANGES. UPPER LEVEL TROF MOVES THROUGH THE AREA EARLY IN
THE PERIOD BUT REMAINS OVER EASTERN NEW ENGLAND STARTING MONDAY.
STEADY SOAKING RAIN FRIDAY NIGHT TO SATURDAY NIGHT THEN IN
NORTHWEST FLOW WITH SOME SHOWERS AND SLIGHTLY COLDER TEMPERATURES
THAN NORMAL. WITH TEMPERATURES WELL ABOVE NORMAL NOW THIS AIR WILL
FEEL COLD.
PREVIOUS DISCUSSION...
XTNDD PD FEATURES A LRG UPR LOW BRINGING UNSETTLED WX TO THE FCST
AREA. SFC FNTL BNDRY PASSES LATE FRI OR EARLY SAT USHERING IN
COOLER AIR AS THE UPR LOW SETTLES OVER THE ERN GREAT LAKES. AFT A
BRIEF PD OF DRY WX DIRECTLY BHD THE FNT...MOISTURE ASSOCIATED WITH
THE UPR LOW ROTATES INTO THE FCST AREA AND LINGERS THRU MUCH OF
THE PD. DAYTIME TEMPS WILL BE BLO NRML WITH H8 TEMPS TO ARND 8C.
LOW BEGINS TO LIFT LATE IN THE PD...BUT WAA MAY GENERATE A FEW
SHWRS THRU MON.
WITH ONGOING SVR WX...RELIED ON HPC GUID FOR MUCH OF THE XTNDD
PD...WITH ONLY A FEW MINOR ADJUSTMENTS.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
630 AM UPDATE...
MOST SITES VFR TODAY AND TONIGHT. ELM HAS DENSE FOG NOW AND VLIFR
FOG NOW WHICH SHOULD LIFT BY 14Z. TONIGHT ELM WILL HAVE MVFR VSBY
FOG STARTING AROUND 5Z. DRIER AIR COMING IN SO DENSE FOG NOT AS
LIKELY AS THIS MORNING. BGM AND ITH HAVE MVFR VSBYS NOW WHICH
SHOULD BECOME VFR AROUND 12Z.
TODAY A FEW SHOWERS POSSIBLE BUT NOT ENOUGH CONFIDENCE THAT ANY
ONE SITE WILL HAVE SHOWERS...TO PUT IT IN NOW. CIGS WILL STAY VFR
WITH DECREASING LOW LEVEL MOISTURE.
LIGHT AND VARIABLE TO CALM WINDS BECOMING WEST AND INCREASING TO
5 TO 10 KTS. TONIGHT AGAIN LIGHT AND VARIABLE.
.OUTLOOK...
THURSDAY TO FRIDAY MORNING...MAINLY VFR. WIDESPREAD LATE NIGHT
FOG NOT EXPECTED.
FRIDAY AFTERNOON TO SUNDAY...MVFR IN OCCASIONAL SHOWERS. FRIDAY
NIGHT STEADY RAIN.
&&
.CLIMATE...
RECORD DAILY HIGH OF 93 FOR SYRACUSE FOR MAY 29TH. TIED SECOND
HIGHEST MAY MAXIMUM TEMPERATURE AND FIFTH HIGHEST MAY AVERAGE
TEMPERATURE OF 80.5.
BGM MISSED THE RECORD DAILY HIGH TEMPERATURE BY ONE DEGREE.
86 VERSUS RECORD 87 IN 1987 AND 1969.
AVP ALSO MISSED THE RECORD DAILY HIGH TEMPERATURE ONE DEGREE.
90 VERSUS 91 IN 1969 AND 1931.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP/MDP
NEAR TERM...DJP/MDP
SHORT TERM...DJP
LONG TERM...DGM/TAC
AVIATION...TAC
CLIMATE...TAC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
802 PM EDT THU MAY 31 2012
.SYNOPSIS...
WEAK HIGH PRESSURE OVER THE AREA WILL GIVE WAY TO A DEVELOPING WARM
FRONT... WHICH WILL HEAD NORTHWARD THROUGH VIRGINIA TONIGHT. A
POWERFUL STORM SYSTEM WILL APPROACH FROM THE WEST FRIDAY... WITH
COLD FRONT PASSAGE LATE FRIDAY EVENING. HIGH PRESSURE WILL BUILD
OVER THE REGION THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 315 PM THURSDAY...
THROUGH THIS EVENING: THE MAIN CONCERN FOR THE NEXT SEVERAL HOURS IS
THE LOCATION AND AREAL EXTENT OF ANY STORMS. LATEST SURFACE ANALYSIS
SHOWS A HIGHLY DIFFUSE AND WEAK E-W BOUNDARY ACROSS NRN NC. IT IS
ALONG THIS BOUNDARY THAT SEVERAL MODELS... INCLUDING THE 12KM NAM /
4KM NAM CONUS NEST AND RAP... DEVELOP SCATTERED CONVECTION LATE THIS
AFTERNOON. WHILE THIS LOCATION APPEARS REASONABLE GIVEN THE
ANTECEDENT CONDITIONS... THE LOW MOISTURE HERE (BOTH NEAR THE
SURFACE AND WITH BELOW-NORMAL PRECIPITABLE WATER) AND LIKELIHOOD OF
LITTLE MORE THAN MARGINAL INSTABILITY (ESPECIALLY IN THE MID LEVELS
WHERE AIR REMAINS DRY/WARM WITH WEAK LAPSE RATES) WOULD LIMIT
COVERAGE. ANOTHER SUBTLE BOUNDARY SEPARATING DEW POINTS OF 60-65 TO
ITS SOUTH AND 55-60 TO ITS NORTH STRETCHES ACROSS THE SANDHILLS INTO
THE CENTRAL COASTAL PLAIN. THE LAST SEVERAL HRRR MODEL RUNS HAVE
CONSISTENTLY DEVELOPED A FEW STORMS HERE LATER TODAY... ALSO
REASONABLE CONSIDERING THE CONVECTIVE CLOUDS ALREADY FORMING IN THIS
AREA AND CURRENT MLCAPE OF 500-1000 J/KG. WILL HOLD ONTO A MENTION
OF ISOLATED STORMS IN THE SOUTHEAST SECTIONS AS WELL AS OVER THE
NORTH FOR A FEW HOURS LATE THIS AFTERNOON INTO EARLY THIS EVENING...
BEFORE THE LOSS OF HEATING LEADS TO DISSIPATION WITHIN THE WEAK
SHEAR ENVIRONMENT. SURFACE WINDS ARE EXPECTED TO REMAIN FAIRLY LIGHT
FROM THE SOUTH AND SSW AT 6-10 MPH OVERNIGHT... LEADING TO A
DECOUPLING OF THE LOWER TROPOSPHERE AS 925-850 MB WINDS BEGIN TO
STRENGTHEN OUT OF THE SOUTHWEST TO 25-30 MPH... AND THIS STRONG WARM
AIR ADVECTION JUST OFF THE SURFACE LATE TONIGHT MAY ALLOW US TO
RETAIN ENOUGH ELEVATED INSTABILITY FOR ISOLATED SHOWERS OVERNIGHT...
A SCENARIO PAINTED BY THE HIGH-RES WRF-NMM... ALTHOUGH THIS IS
PREDICATED UPON US SEEING A SUFFICIENT RETURN OF DEEPER MOISTURE AND
HIGHER PW VALUES OVERNIGHT. WITH PW EXPECTED TO BE JUST SLIGHTLY
ABOVE NORMAL AT MOST PRIOR TO DAWN FRIDAY... WILL MENTION JUST
ISOLATED SPRINKLES OVERNIGHT. LOWS IN THE MID TO UPPER 60S LOOK
GOOD. -GIH
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 PM THURSDAY...
...SEVERE STORMS POSSIBLE FRIDAY AFTERNOON AND EVENING...
FOR FRIDAY/FRIDAY NIGHT: THE OVERALL SYNOPTIC ENVIRONMENT AS WELL AS
SEVERAL KEY THERMODYNAMIC AND SHEAR PARAMETERS CONTINUE TO SUPPORT A
GOOD CHANCE OF STRONG TO SEVERE STORMS LATE FRIDAY AFTERNOON THROUGH
MUCH OF THE EVENING. THE DIFFUSE BOUNDARY ACROSS NRN NC THIS
AFTERNOON IS EXPECTED TO HAVE MOVED NORTH OF THE STATE FRIDAY...
PLACING CENTRAL NC FULLY IN THE PREFRONTAL WARM SECTOR. DEEP LAYER
SHEAR IS PREDICTED BY THE MODELS TO STRENGTHEN TO AROUND 30-35 KTS
AS THE DEEPENING MID LEVEL TROUGH... ASSOCIATED WITH THE LOW WHICH
MOVES FROM NEAR CHI NE ACROSS MI... DIGS INTO THE MID SOUTH AND
SWINGS THROUGH THE SRN/CENTRAL APPALACHIANS WITH A NEGATIVE TILT AND
DECENT DPVA OVER WRN/NRN NC. WHILE THE GREATEST MID LEVEL HEIGHT
FALLS WILL OCCUR TO OUR NW... WE WILL STILL SEE 20-50 METER DROPS
THROUGH FRIDAY. DYNAMIC FORCING WILL ALSO BE AUGMENTED BY
STRENGTHENING UPPER DIVERGENCE... INDUCED BY BOTH THE UPPER JET CORE
OVER OH/LAKE HURON AS WELL AS THE STRENGTHENING SUBTROPICAL JET OVER
THE SOUTHEAST STATES. THE AGEOSTROPHIC RESPONSE FROM THIS LATTER JET
AS IT ACCELERATES BY ABOUT 30-35 KTS IN 12 HOURS SHOULD CAUSE THE
UPPER DIVERGENCE TO INCREASE RAPIDLY OVER CENTRAL NC INTO VA BY
AFTERNOON... ADDING TO THE OVERALL ASCENT AND SUPPORT FOR ORGANIZED
STORMS. 850 MB WINDS DO SPEED UP TO 35-45 KTS OVER CENTRAL NC BY
AFTERNOON... ALTHOUGH THE STRONGEST WINDS WILL BE FOUND TO OUR NORTH
THROUGH VA/PA/NY. AS LOW LEVEL TEMPS AND DEW POINTS INCREASE WITH
STEADY OR COOLING MID LEVELS... INSTABILITY IS EXPECTED TO BECOME
MODERATE BY AFTERNOON WITH MODELS INDICATING MLCAPE OF 1000-1800
J/KG... AROUND 500-800 J/KG OF THIS LOCATED IN THE -10C TO -30C
LAYER... SUGGESTIVE OF A LARGE HAIL THREAT WITH ANY STORMS. WHILE
THE 0-1 KM SRH WILL LIKELY BE MAXIMIZED IN THE VICINITY OF THE
NORTHWARD-RETREATING WARM FRONT... 0-1 KM WIND VECTORS AND DERIVED
PARAMETERS SUCH AS THE BULK RICHARDSON NUMBER CONTINUE TO SUPPORT
THE POTENTIAL FOR SUPERCELLS IN CENTRAL NC. AT THE VERY LEAST WE ARE
LIKELY TO SEE AN ORGANIZED SQUALL LINE WITH A RISK OF LARGE HAIL AS
WELL AS DAMAGING WINDS WITHIN BOWING SEGMENTS. THE LATEST MODEL RUNS
CONTINUE TO PLACE THE GREATEST SEVERE RISK OVER THE CENTRAL AND
EASTERN CWA -- ALTHOUGH SEVERE STORMS COULD OCCUR ANYWHERE -- AND
MAINLY BETWEEN THE HOURS OF 4 PM AND 10 PM. HIGHS 84-90 WITH SW
WINDS 10-15 MPH GUSTING TO 22-27 MPH AFTER THE NOCTURNAL JET MIXES
OUT. GRADUAL CLEARING OVERNIGHT AS THE COLD FRONT MOVES EAST OF THE
AREA AND AS THE MID LEVEL VORTICITY LOBE SWINGS BY TO OUR NORTH.
LOWS 58-65. -GIH
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 255 PM THURSDAY...
BASED ON A MODEL CONSENSUS...FRIDAY EVENINGS CONVECTION WILL BE NEAR
THE COAST AT 12Z SATURDAY MORNING AS THE COLD FRONT PUSHES THROUGH
THE COASTAL PLAIN. A TRAILING UPPER JET WILL SURGE SOUTH UNDERNEATH
AN UPPER LOW OVER THE GREAT LAKES AND ACROSS THE TN VALLEY SATURDAY
AND SATURDAY NIGHT. SOME MID AND HIGH CLOUDS SHOULD ACCOMPANY THE
FAST FLOW ALOFT..SO WHILE SKIES SHOULD BE MOSTLY CLEAR IMMEDIATELY
BEHIND THE FRONT SATURDAY...WE WILL SHOW AN INCREASE IN CLOUD COVER
LATE SATURDAY. DESPITE THE UPPER JET AND A SHOT OF MODEST
DPVA...FORECAST SOUNDINGS APPEAR TO BE TOO TABLE AND DRY
FOR MEASURABLE PRECIP...AND THE NAM IS THE ONLY MODEL CURRENTLY
SHOWING ANY LIGHT PRECIP AT ALL. 850MB TEMPS ARE FORECAST TO FALL
TO AROUND 9-10C...AND DRY ADIABATIC MIXING AND LOW LEVEL THICKNESSES
SCHEMES ALL SUGGEST HIGHS UNDER GUIDANCE IN THE UPPER 70S. LOWS
SATURDAY NIGHT IN THE MID 50S. MORE OF THE SAME IS EXPECTED ON
SUNDAY WITH RELATIVELY DRY NORTHWESTERLY FLOW ALOFT....THOUGH WEAK
HEIGHT RISES AND DOWNSLOPE FLOW SHOULD SPRING HIGHS UP INTO THE LOW
TO MID 80S.
AMPLIFIED FLOW WITH AN OMEGA BLOCK IS THEN EXPECTED OVER THE CONUS
NEXT WEEK...LEADING TO EAST AND WEST COAST TROUGHS AND A RIDGE OVER
THE CENTRAL US. NORTHWESTERLY FLOW IS FORECAST TO CONTINUE MONDAY
BEFORE MODELS SHOW VORTICITY SWINGING AROUND THE EAST COAST
TROUGH...SOUTH ACROSS THE MID ATLANTIC STATES TO THE CAROLINAS.
WHILE THERE IS GENERALLY GOOD LARGE SCALE AGREEMENT...THE ECMWF AND
GFS VARY ON THE AMPLITUDE/TIMING OF FORCING AND THE LOCATION OF THE
MEAN FRONTAL ZONE...WHICH SHOULD STRETCH FROM THE SOUTHEAST US TO
THE UPPER MIDWEST. THIS LEADS TO A LOW CONFIDENCE FORECAST
REGARDING THE TIMING AND DURATION OF PRECIP CHANCES FROM LATE MONDAY
THROUGH THE END OF THE PERIOD. HIGHS ARE EXPECTED TO BE AROUND
NORMAL MONDAY IN THE MID 80S...FALLING TO SLIGHTLY BELOW NORMAL WITH
INCREASING PRECIP CHANCES THROUGH MID WEEK.
&&
.AVIATION /00Z THURSDAY THROUGH TUESDAY/...
AS OF 800 PM THURSDAY...
RESIDUAL LIGHT RAIN -- THE REMAINS OF EARLIER SHOWERS AND STORMS TO
THE WEST OF THE TRIAD TERMINALS -- MAY AFFECT KINT AND KGSO THROUGH
AROUND 01Z. ONLY A SLIGHT CHANCE OF A SHOWER OR STORM WILL CONTINUE
THROUGH MOST OF THE NIGHT. HOWEVER...THE RETREAT OF A WARM FRONT
FROM THE SOUTH LATE TONIGHT WILL CAUSE AREAS OF IFR STRATUS TO
DEVELOP AND SPREAD NORTHWARD ACROSS CENTRAL NC BETWEEN 08-13Z...
ESPECIALLY AT KINT/KGSO/KRDU. A CHANCE OF SHOWERS OR AN ISOLATED
THUNDERSTORM...AND MARGINAL LOW LEVEL WIND SHEAR IF SURFACE WINDS
REMAIN LIGHT...WILL ALSO ACCOMPANY THE WARM FRONT DURING THAT TIME.
DAYTIME HEATING WILL CAUSE GENERALLY SOUTH SOUTHEASTERLY SURFACE
WINDS TO INCREASE AT GUST AT TIMES AROUND 20 KTS AND ALSO TRIGGER
INITIALLY SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BY THE
MIDDAY TO EARLY AFTERNOON HOURS. WIDESPREAD SHOWERS AND STORMS --
SOME LIKELY SEVERE WITH ALL SEVERE WEATHER HAZARDS AND SOME POSSIBLY
SIGNIFICANT -- WILL FOLLOW FOR MID AFTERNOON THROUGH THE EVENING
HOURS...OWING TO THE PASSAGE OF A POWERFUL LOW PRESSURE SYSTEM
THROUGH THE EASTERN US. -MWS
LOOKING BEYOND 00Z SATURDAY: MVFR CIGS MAY BRIEFLY LINGER BEHIND
THE COLD FRONT LATE FRIDAY NIGHT. VFR CIGS ARE EXPECTED LATE
SATURDAY THROUGH SUNDAY DUE TO UPPER LEVEL DISTURBANCES PASSING
OVERHEAD. CONDITIONS WILL REMAIN VFR THROUGH MONDAY... THEN
ADDITIONAL DISTURBANCES AND A BACKDOOR COOL FRONT MAY BRING MVFR
CONDITIONS MONDAY NIGHT/TUESDAY. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...MWS/HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
128 PM EDT WED MAY 30 2012
.SYNOPSIS...
THE CENTER OF TROPICAL DEPRESSION BERYL WILL TRACK NORTHEASTWARD
ALONG THE SOUTHERN OUTER BANKS THIS AFTERNOON... THEN MOVE QUICKLY
NORTHEAST AWAY FROM THE AREA BY THIS EVENING. A COLD FRONT WILL MOVE
IN FROM THE WEST LATE FRIDAY AND FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1020 AM WEDNESDAY...
REST OF TODAY: HAVE OPTED TO DROP THE SOUTHERN PORTIONS OF THE FLASH
FLOOD WATCH... WHERE HEAVY RAIN HAS ALREADY EXITED. OTHERWISE...
FORECAST IS GENERALLY ON TRACK. THE CENTER OF BERYL BASED ON
SATELLITE AND RADAR IMAGERY HAS MOVED TO A POSITION BETWEEN MYR AND
ILM... IN LINE WITH THE NHC FORECAST TRACK. AS BERYL MAY BE
TRANSITIONING TO A POST-TROPICAL STORM AS IT INGESTS DRY AIR ON ITS
SOUTH SIDE... MUCH OF THE RAIN SHIELD IN THE LAST SEVERAL HOURS HAS
BEEN CONFINED TO LOCATIONS NORTHWEST THROUGH NORTHEAST OF THE
CENTER... WITH THE HEAVIEST PRECIP TO THE NORTHWEST OVER ERN NC
WITHIN A ZONE OF MASS CONVERGENCE ASSOCIATED WITH A WEAK INVERTED
SURFACE TROUGH. UPPER DIVERGENCE REMAINS MAXIMIZED IN THIS AREA AS
WELL WITHIN THE RIGHT ENTRANCE REGION OF AN UPPER JET CENTERED OVER
THE ERN GREAT LAKES. RAINFALL ALONG AND EAST OF HIGHWAY ONE HAS BEEN
ABOUT ONE TO TWO INCHES... AND WITH ANOTHER HALF TO ONE INCH
POSSIBLE... EARLIER STORM TOTAL RAINFALL FORECASTS APPEAR TO BE
QUITE GOOD. WILL RETAIN HIGH RAIN CHANCES IN THE EAST... SLOWLY
EXITING WEST TO EAST THROUGH THE AFTERNOON... ENDING LAST IN THE
NORTHEAST FORECAST AREA. IT SHOULD BE NOTED THAT RECENT MESOANALYSES
FROM SPC ARE DEPICTING A SMALL AREA OF HIGHER 0-3 KM CAPE...
ELEVATED 0-1 KM SRH OF 200-300 M2/S2... AND 25 KTS OF EFFECTIVE BULK
SHEAR NOSING INTO EAST CENTRAL NC... AND WILL NEED TO KEEP A CLOSE
EYE OUT FOR A QUICK WEAK SPIN-UP OR TWO OVER THE FAR SE CWA FOR THE
NEXT SEVERAL HOURS. IN THE WRN CWA... WILL RETAIN A MENTION OF
ISOLATED SHOWERS IN THE WESTERN PIEDMONT AS THE LINGERING LOW LEVEL
MOISTURE AND DRYING ALOFT MAY BRIEFLY BUMP UP INSTABILITY GIVEN THE
PARTLY TO MOSTLY SUNNY SKIES HERE... HOWEVER RAP SOUNDINGS SUGGEST
THAT THE COLUMN WILL SUFFICIENTLY DRY OUT WITH STABILIZING MID
LEVELS TO INHIBIT MOST CONVECTION FROM MID AFTERNOON ONWARD.
ADJUSTING FOR THE INCREASING SUNSHINE IN THE WESTERN CWA AND ONGOING
RAIN IN THE EAST TO LIMIT WARMING... EXPECT HIGHS FROM 87 WEST TO 76
EAST. -GIH
WEAK HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT. MAY SEE AREAS
OF FOG BY THU MORNING ESPECIALLY IN THE EAST. MIN TEMPS IN THE
LOW-MID 60S. -WSS
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 337 AM WEDNESDAY...
THURSDAY AND THURSDAY NIGHT...GFS CONTINUES TO DISPLAY MORE
MOISTURE/INSTABILITY COMPARED TO THE DRIER/MORE STABLE NAM. LATEST
ECMWF OFFERS A BIT OF A COMPROMISE. APPEARS THAT THERE WILL BE
ENOUGH MOISTURE/INSTABILITY ACROSS THE SOUTH AND WEST TO WARRANT A
SLIGHT-SMALL CHANCE POPS LATE THU AFTERNOON-THU NIGHT AS WEAK
PERTURBATIONS AND A WEAK SURFACE WARM FRONT/DEWPOINT BOUNDARY LIFT
NE ACROSS REGION. PRESENCE OF WEAK HEIGHT RISES AND MID LEVEL S/W
RIDGE SUGGEST CONVECTION SHOULD REMAIN FAIRLY LIMITED NORTH-NE OF
RDU THU AFTERNOON-EVENING SO HAVE PLACED LOWEST POPS IN THIS REGION.
RATHER WARM THU AFTERNOON WITH THICKNESSES SUPPORTING MAX TEMPS WELL
INTO THE 80S TO NEAR 90. WARM AND MUGGY THU NIGHT WITH MINS 65-70.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 255 AM WEDNESDAY...
FRIDAY AND FRIDAY NIGHT:
CLOSED MID/UPPER LOW AND ASSOCIATED PRIMARY SURFACE LOW ARE FORECAST
TO LIFT NORTH/NORTHEASTWARD FROM THE MIDWEST/OHIO VALLEY INTO THE
GREAT LAKES REGION ON FRIDAY AND BECOME STACKED. THE SURFACE COLD
FRONT WITH THIS SYSTEM IS NOT EXPECTED TO MOVE THROUGH THE AREA
UNTIL LATE FRIDAY AFTERNOON INTO THE EARLY HOURS OF SATURDAY
MORNING... WITH THE FRONT LOCATED NEAR THE NC COAST BY 12Z SATURDAY
(WITH MOST MODELS NOW AGREEING ON THIS TIME FRAME... MUCH BETTER
THAN 24 HOURS AGO). GIVEN THE RATHER STRONG TROUGH ALOFT AND
IMPROVING LARGE SCALE LIFT ACROSS THE AREA FOR THIS TIME OF YEAR
EXPECT WE MAY SEE AN ORGANIZED BAND OF SHOWERS AND STORMS ALONG OR
JUST AHEAD OF THE FRONT. DEEP LAYER SHEAR IS EXPECTED TO RANGE FROM
25 TO 35 KTS JUST AHEAD OF THE FRONT. MLCAPE VALUES ARE EXPECTED TO
BE IN THE 800 TO 1500 J/KG RANGE OUT AHEAD OF THE FRONT. 0-1KM SRH
JUST AHEAD OF THE FRONT IS PROGGED TO INCREASE TO AROUND 100-150
M2/S2... WITH THE 12Z ECWMF SHOWING A POSSIBLE SURFACE LOW TRACK
ALONG THE FRONT ACROSS THE WESTERN/NORTHWESTERN PIEDMONT. THUS...
CANNOT COMPLETELY RULE OUT A TORNADO THREAT. HOWEVER... THINK THE
MAIN THREAT WILL BE FROM DAMAGING WINDS ASSOCIATED WITH AN ORGANIZED
LINE ALONG OR JUST AHEAD OF THE FRONT. THUS... WILL CONTINUE TO
MENTION THE POTENTIAL FOR STRONG TO SEVERE STORMS FRIDAY AFTERNOON
INTO FRIDAY NIGHT ACROSS THE ENTIRE AREA. WILL KEEP POPS IN THE
LIKELY CATEGORY FOR NOW... WITH HOPES OF NARROWING DOWN THE TIME
FRAME IN FUTURE FORECASTS.
WILL CONTINUE TO GO WITH HIGH TEMPS RANGING FROM THE LOWER 80S NW TO
AROUND 90 ACROSS THE EAST/SOUTHEAST... WITH LOCATIONS ACROSS THE FAR
EAST POSSIBLY NOT SEEING ANY PRECIP UNTIL LATE IN THE DAY/EVENING.
LOWS SATURDAY MORNING ARE EXPECTED TO RANGE FROM THE UPPER 50S NW TO
THE LOWER TO MID 60S SE.
SATURDAY THROUGH TUESDAY:
MEDIUM RANGE MODELS HAVE TRENDED MORE TOWARDS KEEPING CENTRAL NC IN
CYCLONIC FLOW ALOFT DURING THIS TIME FRAME... WITH A DEEP UPPER
LEVEL LOW EXPECTED TO SHIFT EASTWARD AND BE CENTERED OFF OF THE
NORTHEAST U.S. COAST (THIS KEEP CENTRAL NC SUSCEPTIBLE TO
DISTURBANCES ALOFT ROTATING THROUGH THE CYCLONIC FLOW ALOFT) BY
EARLY NEXT WEEK. THUS... AFTER A DRY SATURDAY... CONFIDENCE
DECREASES IN THE FORECAST. EXPECT WE MAY SEE SOME PERIODS OF SHOWERS
AND STORMS DURING THIS TIME FRAME... WITH HIGHS GENERALLY IN THE 80S
(MAYBE SOME 70S FOR HIGHS ON SATURDAY THOUGH) AND LOWS GENERALLY IN
THE 60S. FOR NOW WILL GO WITH POPS NO HIGHER THAN SLIGHT CHANCE FOR
SUNDAY THROUGH TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 125 PM WEDNESDAY...
AVIATION CONDITIONS WILL QUICKLY IMPROVE OVER CENTRAL NC THIS
AFTERNOON... AS THE CENTER OF T.D. BERYL MOVES TO THE NE OVER THE
SOUTHERN OUTER BANKS. THE ASSOCIATED SHIELD OF MODERATE TO HEAVY
RAIN AND MVFR TO IFR CONDITIONS HAS MOVED WELL EAST OF INT/GSO...
WHERE THE ARRIVAL OF DRIER AIR FROM THE WEST WILL ENSURE CONTINUED
VFR CONDITIONS THROUGH THURSDAY AFTERNOON. FARTHER EAST... MVFR/IFR
CONDITIONS PERSIST AT RDU/RWI/FAY... BUT THESE WILL IMPROVE OVER THE
NEXT FEW HOURS... WITH VFR CONDITIONS RETURNING WEST TO EAST BETWEEN
19Z AND 22Z. NORTHERLY WINDS SUSTAINED AT 8-12 KTS WILL SPORADICALLY
GUST TO 18-24 KTS... HOWEVER THESE WILL BE INFREQUENT AND WILL
DISSIPATE BETWEEN 21Z AND 02Z. LOW LEVEL MOISTURE WILL REMAIN HIGH
AT RDU/RWI/FAY THIS EVENING LEADING TO AREAS OF SHALLOW GROUND FOG
AFTER 02Z AS WINDS BECOME LIGHT. BUT AS THE LOW LEVELS DRY OUT
OVERNIGHT... ANY FOG SHOULD DISSIPATE TOWARD MORNING. ANY CIGS
THURSDAY AFTERNOON WILL BE VFR.
LOOKING BEYOND 18Z THURSDAY AFTERNOON... A PERIOD OF IFR VSBYS IS
POSSIBLE LATE THURSDAY NIGHT/FRIDAY MORNING AS A WARM FRONT MOVES
THROUGH THE AREA. MVFR CIGS/VSBYS ARE POSSIBLE FRIDAY EVENING WITHIN
SHOWERS AND THUNDERSTORMS PRECEDING A COLD FRONT. VFR CONDITIONS
SHOULD RETURN FOR SATURDAY THROUGH MONDAY. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ028-042-
043-078-089.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
459 PM CDT WED MAY 30 2012
.UPDATE...
WRF...NAM AND GFS ARE ALL VIRTUALLY BONE DRY OVERNIGHT. RUC STILL
TRYING TO HANG ON TO CONVECTION WHICH HAS YET TO OCCUR. CURRENT
FCST IS IN THE 20-30 PERCENT RANGE. CONVECTION COULD STILL FIRE
BUT ITS LOOKING LESS AND LESS LIKELY.
THE PLAN FOR TONIGHT WILL BE TO GIVE THE CONVECTION CHANCES
ANOTHER HOUR OR TWO BEFORE WITHDRAWING THE OVERNIGHT POPS.
OVERNIGHT UPPER DIVERGENCE AND MOISTURE LEVELS ARE HELD AT
BAY. HOWEVER...MAY KEEP A SLIGHT CHANCE GOING ACROSS OUR SOUTHWEST AS PER
THE CURRENT PROXIMITY OF THIS AFTERNOONS CONVECTION.
OTW...QUIET NIGHT...ESPECIALLY COMPARED TO WHAT MAY BE TOMORROW AT
THIS TIME.
NO UPDATE AT THIS MOMENT...BUT LOOK FOR UPDATE WITH THE NEXT FEW HOURS.
&&
.PREV DISCUSSION... /ISSUED 311 PM CDT WED MAY 30 2012/
DISCUSSION...
AIR MASS SOMEWHAT STABLE THIS AFTERNOON ACROSS THE TENNESSEE
VALLEY WITH TEMPS IN THE 80S. DRIER AIR ALOFT HAS MIXED DOWN TO
THE SURFACE. WILL HAVE SMALL POPS IN FOR TONIGHT BUT THINK WE WILL
HAVE TO WAIT ON BOUNDARY TO OUR SOUTH TO LIFT NORTHWARD INTO
TENNESSEE THURSDAY MORNING TO PROVIDE FOCUS. EXPECT WE WILL SEE
SHOWERS AND STORMS ON THE INCREASE THURSDAY ESPECIALLY BY
AFTERNOON IN MOST AREAS. SHOWERS AND STORMS LOOK CATEGORICAL
THURSDAY NIGHT...ESPECIALLY EVENING. SOME STORMS COULD BE SEVERE
IN THE MID STATE LATE AFTERNOON AND THURSDAY EVENING AS SURFACE
LOW UNDERGOES CYCLOGENSIS AS IT ROLLS EAST FROM OKLAHOMA ON
THURSDAY AND INTO THE TENNESSEE AND OHIO VALLEYS BY LATE IN THE
DAY THURSDAY. WIND PROFILES WOULD SUGGEST DAMAGING WINDS AND LARGE
HAIL TO BE THE MAIN THREAT. RAIN SHOULD END FROM THE WEST FRIDAY
MORNING WITH HIGH PRESSURE WORKING INTO THE AREA FROM MISSOURI. A
DIRTY SURFACE RIDGE WILL BE OVER THE TENNESSEE VALLEY FOR THE NEXT
SEVERAL DAYS AS UPPER TROUGH RULES...WITH NO SIGNIFICANT RAIN
CHANCE UNTIL ABOUT TUESDAY OF NEXT WEEK AND THEN MODELS HAVE
FAIRLY LOW QPF.
AND NOW A LITTLE TRIVIA: NASHVILLE IS ON PACE TO HAVE THE 6TH
WARMEST MAY ON RECORD AND THE WARMEST SINCE 1991. NASHVILLE HAD
TWO DAYS OF 95 DEGREE HEAT THIS MONTH. THE HOTTEST TEMPERATURE
EVER RECORDED IN THE MONTH OF MAY IS 96 BACK IN 1937.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1238 PM CDT WED MAY 30 2012
.UPDATE...
AFTER COORDINATION WITH SPC... SEVERE WATCH HAS BEEN ISSUED FOR
EAST CENTRAL AR AND MUCH OF NORTH MS. RADAR SHOWED A STRONG TO
SEVERE LINE LIFTING INTO EAST CENTRAL AR...RIDING ALONG AN OLD
OUTFLOW BOUNDARY AND ORGANIZED BY SOUTHERN MO/SOUTHERN IL SHORTWAVE.
OUTFLOW BOUNDARY THAT DROPPED INTO WEST TN EARLIER THIS MORNING
HAS LED A SLIGHTLY MORE STABLE AIRMASS...BUT A FEW STRONG STORMS
WILL STILL BE POSSIBLE IN THE MEMPHIS AREA.
PWB
&&
.PREV DISCUSSION... /ISSUED 1223 PM CDT WED MAY 30 2012/
UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION
PREV DISCUSSION... /ISSUED 1025 AM CDT WED MAY 30 2012/
UPDATE...
SHOWERS AND THUNDERSTORMS CONTINUED OVER NORTHEAST AR AT MIDMORNING.
OVERALL A DECREASING INTENSITY TREND WAS SHOWN BY RADAR...THOUGH A
FEW STRONGER CELLS WERE NOTED OVER NORTH CENTRAL AR. THE STORMS
HAD FORMED ON THE NOSE OF A LOW LEVEL THETA E RIDGE OVER SOUTHERN
AR... AND WERE AIDED BY A SHORTWAVE TROF EVIDENT ON WATER VAPOR
IMAGERY...LIFTING EAST THROUGH SOUTHERN MO.
FORECAST WAS RECENTLY UPDATED TO LOWER TEMPS OVER NORTHEAST AR AND
PORTIONS OF WEST TN...WHERE AFTERNOON TEMPS WILL BE AFFECTED BY
THE COLD POOL FROM THIS MORNING/S STORMS. OTHER UPDATES INCLUDED A
BUMP IN POPS INTO NORTHWEST TN... WHERE OUTFLOW SHOULD STALL NEAR
PEAK AFTERNOON SURFACE HEATING.
PWB
PREV DISCUSSION... /ISSUED 708 AM CDT WED MAY 30 2012/
UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 30 2012/
DISCUSSION...FORECAST FOCUS ON TEMPS AND THUNDERSTORM CHANCES
THROUGH THE PERIOD.
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AREAS OF FOG HAVE DEVELOPED EARLY THIS MORNING ACROSS PORTIONS OF
WEST TENNESSEE AND NORTHEAST MISSISSIPPI WHERE TEMPERATURES HAVE
FALLEN INTO THE LOW 60S. FOG SHOULD BURN OFF QUICKLY THIS MORNING
UNDER CLEAR SKIES.
ATTENTION THEN TURNS TO THE DECAYING MCS OVER EASTERN OK...SWRN
MO...WRN AR...AND NERN TX. SYNOPTIC SCALE MODELS HAVE FAILED RATHER
MISERABLY IN THEIR DEPICTION OF THIS MCS IN THE 06Z-12Z TIME FRAME
HAVING IT DISPLACED MUCH TOO FAR NORTH. ADDITIONAL SCATTERED
STORMS HAVE ALSO FIRED RECENTLY ACROSS CENTRAL AR. MESOSCALE
MODELS SUCH AS THE HRRR HAVE PERFORMED MUCH BETTER AND WILL FOLLOW
THOSE FOR CONVECTIVE TRENDS TODAY. THAT BEING SAID...THE SOUTHERN
PLAINS MCS IS EXPECTED TO DIVE SOUTHEAST INTO LOUISIANA THIS
MORNING. ITS RESIDUAL OUTFLOW BOUNDARY WILL SLOWLY PROGRESS
EAST/NORTHEASTWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON.
AN UNCAPPED...MODERATELY UNSTABLE ATMOSPHERE WILL SUPPORT THE
DEVELOPMENT OF SOME STORMS ALONG THIS BOUNDARY ACROSS ERN
AR...SWRN TN...NWRN MS THIS AFTERNOON. BUMPED UP POPS INTO THE
30-40 PCT RANGE THERE WITH DIMINISHING POPS TO THE EAST. LARGE
DEW POINT DEPRESSIONS AT THE SURFACE AS TEMPERATURES RISE AGAIN
INTO THE LOW 90S MAY LEAD TO GUSTY WINDS WITH SOME OF THESE
STORMS.
LOW PRESSURE WILL BE FORMING OVER OKLAHOMA TONIGHT AND BEGIN TO
TRACK NORTHEAST INTO SOUTHERN MISSOURI THURSDAY MORNING. ROBUST
THUNDERSTORM DEVELOPMENT IS EXPECTED AGAIN TODAY ACROSS OKLAHOMA
WHICH WILL GROW INTO ANOTHER MCS TONIGHT. IT REMAINS UNCLEAR HOW
FAR EAST THIS MCS WILL TRACK OVERNIGHT...SOME INDICATIONS SUGGEST
IT MAY REACH EASTERN ARKANSAS LATE. THEREFORE...KEPT MODERATE CHC
POPS ACROSS THAT REGION.
WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE MIDSOUTH THURSDAY
AS MID LEVEL HEIGHT FALLS OVERSPREAD A WARM/MOIST WARM SECTOR.
WHILE WIND SHEAR REMAINS LOW AT LEAST EARLY...MODERATELY UNSTABLE
CONDITIONS WILL SUPPORT STORM CLUSTERS CAPABLE OF WIND DAMAGE. THE
RISK OF SEVERE WILL INCREASE BY LATE AFTERNOON AND EVENING ACROSS
THE CENTRAL AND EASTERN AREAS AS THE MID LEVEL FLOW STRENGTHENS
JUST AHEAD OF THE COLD FRONT. MAY SEE MESSY CLUSTERS OF THUNDERSTORMS
EVENTUALLY FORM A SQUALL LINE EAST OF THE MISSISSIPPI RIVER AFTER
21Z-00Z WITH ATTENDANT WIND DAMAGE THREAT. LOW LEVEL FLOW/VEERING
DOES NOT APPEAR SUPPORTIVE FOR TORNADIC DEVELOPMENT SO WILL REMOVE
THAT THREAT FROM THE HWO.
GFS STILL LAGS BACK WITH THE COLD FRONT...WITH ALL OTHER LARGE
SCALE MODELS IN GOOD AGREEMENT DRYING THINGS OUT BY 12Z FRIDAY.
COOLER AND DRIER AIR WILL BRING A REFRESHING FRIDAY WITH HIGHS
ONLY IN THE LOW TO MID 70S AND LOWS FRIDAY NIGHT IN THE UPPER
40S/MID 50S.
LONG TERM...SATURDAY THROUGH TUESDAY.
WAA RETURNS FOR THE WEEKEND AS A BUILDING RIDGE OVER THE PLAINS
BEGINS TO BUILD EASTWARD. HOWEVER...MODELS HAVE SHIFTED THE RIDGE
AXIS A BIT WESTWARD WITH RECENT RUNS AND NOW KEEPS THE MIDSOUTH IN
A NORTHWEST FLOW WITH A PESKY WEAK FRONT REMAINING IN PLACE.
THUS...SMALL CHANCES FOR THUNDERSTORMS HAVE BEEN INTRODUCED FOR
SUNDAY AND BEYOND. TEMPERATURES STILL LOOK WARM...UPPER 80S TO
LOWER 90S.
BORGHOFF
&&
.AVIATION...
18Z TAF CYCLE
STRENGTHENING LINE OF CONVECTION BETWEEN MEM AND LZK WILL CONTINUE
TO TRACK EAST NORTHEAST THROUGH THE AFTERNOON. MAIN THREAT FOR THE
STRONGEST CONVECTION WILL RIDE ALONG I-40 AND POINTS SOUTH. HAVE
PLACED TEMPO FOR THUNDER IN AT MEM AND LATER FOR TUP AS CONVECTION
WILL LIKELY TRACK ACROSS ALL OF NORTH MISSISSIPPI THROUGH THE EARLY
EVENING HOURS. HEAVIEST THUNDERSTORM ACTIVITY WILL DROP CONDITIONS
DOWN TO MVFR...OTHERWISE VFR CONDITIONS WILL BE THE RULE. JBR
INITIALLY WILL SEE VCTS AND TEMPO SHOWERS...WHILE MORE STABLE AIR
WILL LIKELY KEEP MKL OUT OF THE THREAT. NORTH TO NORTHEAST WINDS
IN THE 10-20 KT RANGE WILL CONTINUE AT MEM...MKL...AND JBR AND
EVENTUALLY TUP WILL SEE A NORTH WIND SHIFT AHEAD OF THE LINE OF
STORMS.
STORMS WILL DIMINISH AND SKIES WILL CLEAR FROM WEST TO EAST BEHIND
THE LINE...WITH LIGHT WINDS BY EARLY EVENING. HOWEVER CENTRAL
PLAINS CONVECTION AHEAD OF A COLD FRONT IS LIKELY TO MOVE IN AT
THE END OF THE PERIOD WITH THE NEXT THREAT FOR STORMS.
JAB
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 73 82 56 74 / 30 90 50 10
MKL 66 81 55 71 / 30 80 70 10
JBR 69 77 54 74 / 40 90 30 10
TUP 69 86 58 73 / 20 60 80 20
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1223 PM CDT WED MAY 30 2012
.UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1025 AM CDT WED MAY 30 2012/
UPDATE...
SHOWERS AND THUNDERSTORMS CONTINUED OVER NORTHEAST AR AT MIDMORNING.
OVERALL A DECREASING INTENSITY TREND WAS SHOWN BY RADAR...THOUGH A
FEW STRONGER CELLS WERE NOTED OVER NORTH CENTRAL AR. THE STORMS
HAD FORMED ON THE NOSE OF A LOW LEVEL THETA E RIDGE OVER SOUTHERN
AR... AND WERE AIDED BY A SHORTWAVE TROF EVIDENT ON WATER VAPOR
IMAGERY...LIFTING EAST THROUGH SOUTHERN MO.
FORECAST WAS RECENTLY UPDATED TO LOWER TEMPS OVER NORTHEAST AR AND
PORTIONS OF WEST TN...WHERE AFTERNOON TEMPS WILL BE AFFECTED BY
THE COLD POOL FROM THIS MORNING/S STORMS. OTHER UPDATES INCLUDED A
BUMP IN POPS INTO NORTHWEST TN... WHERE OUTFLOW SHOULD STALL NEAR
PEAK AFTERNOON SURFACE HEATING.
PWB
PREV DISCUSSION... /ISSUED 708 AM CDT WED MAY 30 2012/
UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 30 2012/
DISCUSSION...FORECAST FOCUS ON TEMPS AND THUNDERSTORM CHANCES
THROUGH THE PERIOD.
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AREAS OF FOG HAVE DEVELOPED EARLY THIS MORNING ACROSS PORTIONS OF
WEST TENNESSEE AND NORTHEAST MISSISSIPPI WHERE TEMPERATURES HAVE
FALLEN INTO THE LOW 60S. FOG SHOULD BURN OFF QUICKLY THIS MORNING
UNDER CLEAR SKIES.
ATTENTION THEN TURNS TO THE DECAYING MCS OVER EASTERN OK...SWRN
MO...WRN AR...AND NERN TX. SYNOPTIC SCALE MODELS HAVE FAILED RATHER
MISERABLY IN THEIR DEPICTION OF THIS MCS IN THE 06Z-12Z TIME FRAME
HAVING IT DISPLACED MUCH TOO FAR NORTH. ADDITIONAL SCATTERED
STORMS HAVE ALSO FIRED RECENTLY ACROSS CENTRAL AR. MESOSCALE
MODELS SUCH AS THE HRRR HAVE PERFORMED MUCH BETTER AND WILL FOLLOW
THOSE FOR CONVECTIVE TRENDS TODAY. THAT BEING SAID...THE SOUTHERN
PLAINS MCS IS EXPECTED TO DIVE SOUTHEAST INTO LOUISIANA THIS
MORNING. ITS RESIDUAL OUTFLOW BOUNDARY WILL SLOWLY PROGRESS
EAST/NORTHEASTWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON.
AN UNCAPPED...MODERATELY UNSTABLE ATMOSPHERE WILL SUPPORT THE
DEVELOPMENT OF SOME STORMS ALONG THIS BOUNDARY ACROSS ERN
AR...SWRN TN...NWRN MS THIS AFTERNOON. BUMPED UP POPS INTO THE
30-40 PCT RANGE THERE WITH DIMINISHING POPS TO THE EAST. LARGE
DEW POINT DEPRESSIONS AT THE SURFACE AS TEMPERATURES RISE AGAIN
INTO THE LOW 90S MAY LEAD TO GUSTY WINDS WITH SOME OF THESE
STORMS.
LOW PRESSURE WILL BE FORMING OVER OKLAHOMA TONIGHT AND BEGIN TO
TRACK NORTHEAST INTO SOUTHERN MISSOURI THURSDAY MORNING. ROBUST
THUNDERSTORM DEVELOPMENT IS EXPECTED AGAIN TODAY ACROSS OKLAHOMA
WHICH WILL GROW INTO ANOTHER MCS TONIGHT. IT REMAINS UNCLEAR HOW
FAR EAST THIS MCS WILL TRACK OVERNIGHT...SOME INDICATIONS SUGGEST
IT MAY REACH EASTERN ARKANSAS LATE. THEREFORE...KEPT MODERATE CHC
POPS ACROSS THAT REGION.
WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE MIDSOUTH THURSDAY
AS MID LEVEL HEIGHT FALLS OVERSPREAD A WARM/MOIST WARM SECTOR.
WHILE WIND SHEAR REMAINS LOW AT LEAST EARLY...MODERATELY UNSTABLE
CONDITIONS WILL SUPPORT STORM CLUSTERS CAPABLE OF WIND DAMAGE. THE
RISK OF SEVERE WILL INCREASE BY LATE AFTERNOON AND EVENING ACROSS
THE CENTRAL AND EASTERN AREAS AS THE MID LEVEL FLOW STRENGTHENS
JUST AHEAD OF THE COLD FRONT. MAY SEE MESSY CLUSTERS OF THUNDERSTORMS
EVENTUALLY FORM A SQUALL LINE EAST OF THE MISSISSIPPI RIVER AFTER
21Z-00Z WITH ATTENDANT WIND DAMAGE THREAT. LOW LEVEL FLOW/VEERING
DOES NOT APPEAR SUPPORTIVE FOR TORNADIC DEVELOPMENT SO WILL REMOVE
THAT THREAT FROM THE HWO.
GFS STILL LAGS BACK WITH THE COLD FRONT...WITH ALL OTHER LARGE
SCALE MODELS IN GOOD AGREEMENT DRYING THINGS OUT BY 12Z FRIDAY.
COOLER AND DRIER AIR WILL BRING A REFRESHING FRIDAY WITH HIGHS
ONLY IN THE LOW TO MID 70S AND LOWS FRIDAY NIGHT IN THE UPPER
40S/MID 50S.
LONG TERM...SATURDAY THROUGH TUESDAY.
WAA RETURNS FOR THE WEEKEND AS A BUILDING RIDGE OVER THE PLAINS
BEGINS TO BUILD EASTWARD. HOWEVER...MODELS HAVE SHIFTED THE RIDGE
AXIS A BIT WESTWARD WITH RECENT RUNS AND NOW KEEPS THE MIDSOUTH IN
A NORTHWEST FLOW WITH A PESKY WEAK FRONT REMAINING IN PLACE.
THUS...SMALL CHANCES FOR THUNDERSTORMS HAVE BEEN INTRODUCED FOR
SUNDAY AND BEYOND. TEMPERATURES STILL LOOK WARM...UPPER 80S TO
LOWER 90S.
BORGHOFF
&&
.AVIATION...
18Z TAF CYCLE
STRENGTHENING LINE OF CONVECTION BETWEEN MEM AND LZK WILL CONTINUE
TO TRACK EAST NORTHEAST THROUGH THE AFTERNOON. MAIN THREAT FOR THE
STRONGEST CONVECTION WILL RIDE ALONG I-40 AND POINTS SOUTH. HAVE
PLACED TEMPO FOR THUNDER IN AT MEM AND LATER FOR TUP AS CONVECTION
WILL LIKELY TRACK ACROSS ALL OF NORTH MISSISSIPPI THROUGH THE EARLY
EVENING HOURS. HEAVIEST THUNDERSTORM ACTIVITY WILL DROP CONDITIONS
DOWN TO MVFR...OTHERWISE VFR CONDITIONS WILL BE THE RULE. JBR
INITIALLY WILL SEE VCTS AND TEMPO SHOWERS...WHILE MORE STABLE AIR
WILL LIKELY KEEP MKL OUT OF THE THREAT. NORTH TO NORTHEAST WINDS
IN THE 10-20 KT RANGE WILL CONTINUE AT MEM...MKL...AND JBR AND
EVENTUALLY TUP WILL SEE A NORTH WIND SHIFT AHEAD OF THE LINE OF
STORMS.
STORMS WILL DIMINISH AND SKIES WILL CLEAR FROM WEST TO EAST BEHIND
THE LINE...WITH LIGHT WINDS BY EARLY EVENING. HOWEVER CENTRAL
PLAINS CONVECTION AHEAD OF A COLD FRONT IS LIKELY TO MOVE IN AT
THE END OF THE PERIOD WITH THE NEXT THREAT FOR STORMS.
JAB
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 88 73 82 56 / 50 30 90 50
MKL 89 66 81 55 / 20 30 80 70
JBR 82 69 77 54 / 50 40 90 30
TUP 93 69 86 58 / 20 20 60 80
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1025 AM CDT WED MAY 30 2012
.UPDATE...
SHOWERS AND THUNDERSTORMS CONTINUED OVER NORTHEAST AR AT MIDMORNING.
OVERALL A DECREASING INTENSITY TREND WAS SHOWN BY RADAR...THOUGH A
FEW STRONGER CELLS WERE NOTED OVER NORTH CENTRAL AR. THE STORMS
HAD FORMED ON THE NOSE OF A LOW LEVEL THETA E RIDGE OVER SOUTHERN
AR... AND WERE AIDED BY A SHORTWAVE TROF EVIDENT ON WATER VAPOR
IMAGERY...LIFTING EAST THROUGH SOUTHERN MO.
FORECAST WAS RECENTLY UPDATED TO LOWER TEMPS OVER NORTHEAST AR AND
PORTIONS OF WEST TN...WHERE AFTERNOON TEMPS WILL BE AFFECTED BY
THE COLD POOL FROM THIS MORNING/S STORMS. OTHER UPDATES INCLUDED A
BUMP IN POPS INTO NORTHWEST TN... WHERE OUTFLOW SHOULD STALL NEAR
PEAK AFTERNOON SURFACE HEATING.
PWB
&&
.PREV DISCUSSION... /ISSUED 708 AM CDT WED MAY 30 2012/
UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 30 2012/
DISCUSSION...FORECAST FOCUS ON TEMPS AND THUNDERSTORM CHANCES
THROUGH THE PERIOD.
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AREAS OF FOG HAVE DEVELOPED EARLY THIS MORNING ACROSS PORTIONS OF
WEST TENNESSEE AND NORTHEAST MISSISSIPPI WHERE TEMPERATURES HAVE
FALLEN INTO THE LOW 60S. FOG SHOULD BURN OFF QUICKLY THIS MORNING
UNDER CLEAR SKIES.
ATTENTION THEN TURNS TO THE DECAYING MCS OVER EASTERN OK...SWRN
MO...WRN AR...AND NERN TX. SYNOPTIC SCALE MODELS HAVE FAILED RATHER
MISERABLY IN THEIR DEPICTION OF THIS MCS IN THE 06Z-12Z TIME FRAME
HAVING IT DISPLACED MUCH TOO FAR NORTH. ADDITIONAL SCATTERED
STORMS HAVE ALSO FIRED RECENTLY ACROSS CENTRAL AR. MESOSCALE
MODELS SUCH AS THE HRRR HAVE PERFORMED MUCH BETTER AND WILL FOLLOW
THOSE FOR CONVECTIVE TRENDS TODAY. THAT BEING SAID...THE SOUTHERN
PLAINS MCS IS EXPECTED TO DIVE SOUTHEAST INTO LOUISIANA THIS
MORNING. ITS RESIDUAL OUTFLOW BOUNDARY WILL SLOWLY PROGRESS
EAST/NORTHEASTWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON.
AN UNCAPPED...MODERATELY UNSTABLE ATMOSPHERE WILL SUPPORT THE
DEVELOPMENT OF SOME STORMS ALONG THIS BOUNDARY ACROSS ERN
AR...SWRN TN...NWRN MS THIS AFTERNOON. BUMPED UP POPS INTO THE
30-40 PCT RANGE THERE WITH DIMINISHING POPS TO THE EAST. LARGE
DEW POINT DEPRESSIONS AT THE SURFACE AS TEMPERATURES RISE AGAIN
INTO THE LOW 90S MAY LEAD TO GUSTY WINDS WITH SOME OF THESE
STORMS.
LOW PRESSURE WILL BE FORMING OVER OKLAHOMA TONIGHT AND BEGIN TO
TRACK NORTHEAST INTO SOUTHERN MISSOURI THURSDAY MORNING. ROBUST
THUNDERSTORM DEVELOPMENT IS EXPECTED AGAIN TODAY ACROSS OKLAHOMA
WHICH WILL GROW INTO ANOTHER MCS TONIGHT. IT REMAINS UNCLEAR HOW
FAR EAST THIS MCS WILL TRACK OVERNIGHT...SOME INDICATIONS SUGGEST
IT MAY REACH EASTERN ARKANSAS LATE. THEREFORE...KEPT MODERATE CHC
POPS ACROSS THAT REGION.
WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE MIDSOUTH THURSDAY
AS MID LEVEL HEIGHT FALLS OVERSPREAD A WARM/MOIST WARM SECTOR.
WHILE WIND SHEAR REMAINS LOW AT LEAST EARLY...MODERATELY UNSTABLE
CONDITIONS WILL SUPPORT STORM CLUSTERS CAPABLE OF WIND DAMAGE. THE
RISK OF SEVERE WILL INCREASE BY LATE AFTERNOON AND EVENING ACROSS
THE CENTRAL AND EASTERN AREAS AS THE MID LEVEL FLOW STRENGTHENS
JUST AHEAD OF THE COLD FRONT. MAY SEE MESSY CLUSTERS OF THUNDERSTORMS
EVENTUALLY FORM A SQUALL LINE EAST OF THE MISSISSIPPI RIVER AFTER
21Z-00Z WITH ATTENDANT WIND DAMAGE THREAT. LOW LEVEL FLOW/VEERING
DOES NOT APPEAR SUPPORTIVE FOR TORNADIC DEVELOPMENT SO WILL REMOVE
THAT THREAT FROM THE HWO.
GFS STILL LAGS BACK WITH THE COLD FRONT...WITH ALL OTHER LARGE
SCALE MODELS IN GOOD AGREEMENT DRYING THINGS OUT BY 12Z FRIDAY.
COOLER AND DRIER AIR WILL BRING A REFRESHING FRIDAY WITH HIGHS
ONLY IN THE LOW TO MID 70S AND LOWS FRIDAY NIGHT IN THE UPPER
40S/MID 50S.
LONG TERM...SATURDAY THROUGH TUESDAY.
WAA RETURNS FOR THE WEEKEND AS A BUILDING RIDGE OVER THE PLAINS
BEGINS TO BUILD EASTWARD. HOWEVER...MODELS HAVE SHIFTED THE RIDGE
AXIS A BIT WESTWARD WITH RECENT RUNS AND NOW KEEPS THE MIDSOUTH IN
A NORTHWEST FLOW WITH A PESKY WEAK FRONT REMAINING IN PLACE.
THUS...SMALL CHANCES FOR THUNDERSTORMS HAVE BEEN INTRODUCED FOR
SUNDAY AND BEYOND. TEMPERATURES STILL LOOK WARM...UPPER 80S TO
LOWER 90S.
BORGHOFF
&&
.AVIATION...
12Z TAF CYCLE
A CLUSTER OF THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS PORTIONS
OF NORTHEAST ARKANSAS THIS MORNING. THESE STORMS FORMED ALONG AN
OUTFLOW BOUNDARY FROM OVERNIGHT CONVECTION OVER THE ARKLATEX
REGION. HAVE INCLUDED A VCTS FOR KJBR EARLY THIS MORNING AS STORMS
MOVE JUST TO THE NORTH. ELSEWHERE EXPECT DRY CONDITIONS THIS
MORNING WITH VFR CEILINGS PREVAILING.
LATEST HRRR HIGH RESOLUTION MODEL SUGGESTS REDEVELOPMENT OF
SCATTERED THUNDERSTORMS ALONG AND WEST OF THE MISSISSIPPI RIVER
THIS AFTERNOON ALONG NEW OUTFLOW BOUNDARIES FROM MORNING
CONVECTION...DAYTIME HEATING...AND WEAK SHORTWAVE DISTURBANCES IN
NORTHWEST FLOW ALOFT. HAVE ADDED VCTS BACK INTO TAFS THIS
AFTERNOON AT KJBR AND KMEM. FURTHER EAST...THINK THE CHANCES FOR
CONVECTION REMAIN TOO LOW TO INCLUDE IN KMKL AND KTUP TAF
FORECASTS. WINDS TODAY WILL BE VARIABLE AND RATHER LIGHT...MAINLY
DRIVEN BY MESOSCALE BOUNDARIES.
ALL LOCATIONS SHOULD BE RAIN FREE THIS EVENING AS THE INITIAL
SHORTWAVE MOVES SOUTHEAST. A STRONGER UPSTREAM DISTURBANCE AND
ASSOCIATED SURFACE LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST
LATE TONIGHT AND HAVE INCLUDED VCTS BACK AGAIN FOR LATE TONIGHT AT
KJBR...KMKL...AND KMEM. WINDS SHOULD REMAIN LIGHT SOUTHERLY
TONIGHT.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 93 73 82 56 / 30 30 90 50
MKL 91 66 81 55 / 20 30 80 70
JBR 88 69 77 54 / 60 40 90 30
TUP 94 69 86 58 / 20 20 60 80
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
708 AM CDT WED MAY 30 2012
.UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 30 2012/
DISCUSSION...FORECAST FOCUS ON TEMPS AND THUNDERSTORM CHANCES
THROUGH THE PERIOD.
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AREAS OF FOG HAVE DEVELOPED EARLY THIS MORNING ACROSS PORTIONS OF
WEST TENNESSEE AND NORTHEAST MISSISSIPPI WHERE TEMPERATURES HAVE
FALLEN INTO THE LOW 60S. FOG SHOULD BURN OFF QUICKLY THIS MORNING
UNDER CLEAR SKIES.
ATTENTION THEN TURNS TO THE DECAYING MCS OVER EASTERN OK...SWRN
MO...WRN AR...AND NERN TX. SYNOPTIC SCALE MODELS HAVE FAILED RATHER
MISERABLY IN THEIR DEPICTION OF THIS MCS IN THE 06Z-12Z TIME FRAME
HAVING IT DISPLACED MUCH TOO FAR NORTH. ADDITIONAL SCATTERED
STORMS HAVE ALSO FIRED RECENTLY ACROSS CENTRAL AR. MESOSCALE
MODELS SUCH AS THE HRRR HAVE PERFORMED MUCH BETTER AND WILL FOLLOW
THOSE FOR CONVECTIVE TRENDS TODAY. THAT BEING SAID...THE SOUTHERN
PLAINS MCS IS EXPECTED TO DIVE SOUTHEAST INTO LOUISIANA THIS
MORNING. ITS RESIDUAL OUTFLOW BOUNDARY WILL SLOWLY PROGRESS
EAST/NORTHEASTWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON.
AN UNCAPPED...MODERATELY UNSTABLE ATMOSPHERE WILL SUPPORT THE
DEVELOPMENT OF SOME STORMS ALONG THIS BOUNDARY ACROSS ERN
AR...SWRN TN...NWRN MS THIS AFTERNOON. BUMPED UP POPS INTO THE
30-40 PCT RANGE THERE WITH DIMINISHING POPS TO THE EAST. LARGE
DEW POINT DEPRESSIONS AT THE SURFACE AS TEMPERATURES RISE AGAIN
INTO THE LOW 90S MAY LEAD TO GUSTY WINDS WITH SOME OF THESE
STORMS.
LOW PRESSURE WILL BE FORMING OVER OKLAHOMA TONIGHT AND BEGIN TO
TRACK NORTHEAST INTO SOUTHERN MISSOURI THURSDAY MORNING. ROBUST
THUNDERSTORM DEVELOPMENT IS EXPECTED AGAIN TODAY ACROSS OKLAHOMA
WHICH WILL GROW INTO ANOTHER MCS TONIGHT. IT REMAINS UNCLEAR HOW
FAR EAST THIS MCS WILL TRACK OVERNIGHT...SOME INDICATIONS SUGGEST
IT MAY REACH EASTERN ARKANSAS LATE. THEREFORE...KEPT MODERATE CHC
POPS ACROSS THAT REGION.
WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE MIDSOUTH THURSDAY
AS MID LEVEL HEIGHT FALLS OVERSPREAD A WARM/MOIST WARM SECTOR.
WHILE WIND SHEAR REMAINS LOW AT LEAST EARLY...MODERATELY UNSTABLE
CONDITIONS WILL SUPPORT STORM CLUSTERS CAPABLE OF WIND DAMAGE. THE
RISK OF SEVERE WILL INCREASE BY LATE AFTERNOON AND EVENING ACROSS
THE CENTRAL AND EASTERN AREAS AS THE MID LEVEL FLOW STRENGTHENS
JUST AHEAD OF THE COLD FRONT. MAY SEE MESSY CLUSTERS OF THUNDERSTORMS
EVENTUALLY FORM A SQUALL LINE EAST OF THE MISSISSIPPI RIVER AFTER
21Z-00Z WITH ATTENDANT WIND DAMAGE THREAT. LOW LEVEL FLOW/VEERING
DOES NOT APPEAR SUPPORTIVE FOR TORNADIC DEVELOPMENT SO WILL REMOVE
THAT THREAT FROM THE HWO.
GFS STILL LAGS BACK WITH THE COLD FRONT...WITH ALL OTHER LARGE
SCALE MODELS IN GOOD AGREEMENT DRYING THINGS OUT BY 12Z FRIDAY.
COOLER AND DRIER AIR WILL BRING A REFRESHING FRIDAY WITH HIGHS
ONLY IN THE LOW TO MID 70S AND LOWS FRIDAY NIGHT IN THE UPPER
40S/MID 50S.
.LONG TERM...SATURDAY THROUGH TUESDAY.
WAA RETURNS FOR THE WEEKEND AS A BUILDING RIDGE OVER THE PLAINS
BEGINS TO BUILD EASTWARD. HOWEVER...MODELS HAVE SHIFTED THE RIDGE
AXIS A BIT WESTWARD WITH RECENT RUNS AND NOW KEEPS THE MIDSOUTH IN
A NORTHWEST FLOW WITH A PESKY WEAK FRONT REMAINING IN PLACE.
THUS...SMALL CHANCES FOR THUNDERSTORMS HAVE BEEN INTRODUCED FOR
SUNDAY AND BEYOND. TEMPERATURES STILL LOOK WARM...UPPER 80S TO
LOWER 90S.
BORGHOFF
&&
.AVIATION...
12Z TAF CYCLE
A CLUSTER OF THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS PORTIONS
OF NORTHEAST ARKANSAS THIS MORNING. THESE STORMS FORMED ALONG AN
OUTFLOW BOUNDARY FROM OVERNIGHT CONVECTION OVER THE ARKLATEX
REGION. HAVE INCLUDED A VCTS FOR KJBR EARLY THIS MORNING AS STORMS
MOVE JUST TO THE NORTH. ELSEWHERE EXPECT DRY CONDITIONS THIS
MORNING WITH VFR CEILINGS PREVAILING.
LATEST HRRR HIGH RESOLUTION MODEL SUGGESTS REDEVELOPMENT OF
SCATTERED THUNDERSTORMS ALONG AND WEST OF THE MISSISSIPPI RIVER
THIS AFTERNOON ALONG NEW OUTFLOW BOUNDARIES FROM MORNING
CONVECTION...DAYTIME HEATING...AND WEAK SHORTWAVE DISTURBANCES IN
NORTHWEST FLOW ALOFT. HAVE ADDED VCTS BACK INTO TAFS THIS
AFTERNOON AT KJBR AND KMEM. FURTHER EAST...THINK THE CHANCES FOR
CONVECTION REMAIN TOO LOW TO INCLUDE IN KMKL AND KTUP TAF
FORECASTS. WINDS TODAY WILL BE VARIABLE AND RATHER LIGHT...MAINLY
DRIVEN BY MESOSCALE BOUNDARIES.
ALL LOCATIONS SHOULD BE RAIN FREE THIS EVENING AS THE INITIAL
SHORTWAVE MOVES SOUTHEAST. A STRONGER UPSTREAM DISTURBANCE AND
ASSOCIATED SURFACE LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST
LATE TONIGHT AND HAVE INCLUDED VCTS BACK AGAIN FOR LATE TONIGHT AT
KJBR...KMKL...AND KMEM. WINDS SHOULD REMAIN LIGHT SOUTHERLY
TONIGHT.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 93 73 82 56 / 30 30 90 50
MKL 92 66 81 55 / 20 30 80 70
JBR 90 69 77 54 / 50 40 90 30
TUP 93 69 86 58 / 20 20 60 80
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
430 AM CDT WED MAY 30 2012
.DISCUSSION...FORECAST FOCUS ON TEMPS AND THUNDERSTORM CHANCES
THROUGH THE PERIOD.
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AREAS OF FOG HAVE DEVELOPED EARLY THIS MORNING ACROSS PORTIONS OF
WEST TENNESSEE AND NORTHEAST MISSISSIPPI WHERE TEMPERATURES HAVE
FALLEN INTO THE LOW 60S. FOG SHOULD BURN OFF QUICKLY THIS MORNING
UNDER CLEAR SKIES.
ATTENTION THEN TURNS TO THE DECAYING MCS OVER EASTERN OK...SWRN
MO...WRN AR...AND NERN TX. SYNOPTIC SCALE MODELS HAVE FAILED RATHER
MISERABLY IN THEIR DEPICTION OF THIS MCS IN THE 06Z-12Z TIME FRAME
HAVING IT DISPLACED MUCH TOO FAR NORTH. ADDITIONAL SCATTERED
STORMS HAVE ALSO FIRED RECENTLY ACROSS CENTRAL AR. MESOSCALE
MODELS SUCH AS THE HRRR HAVE PERFORMED MUCH BETTER AND WILL FOLLOW
THOSE FOR CONVECTIVE TRENDS TODAY. THAT BEING SAID...THE SOUTHERN
PLAINS MCS IS EXPECTED TO DIVE SOUTHEAST INTO LOUISIANA THIS
MORNING. ITS RESIDUAL OUTFLOW BOUNDARY WILL SLOWLY PROGRESS
EAST/NORTHEASTWARD THROUGH THE MORNING INTO THE EARLY AFTERNOON.
AN UNCAPPED...MODERATELY UNSTABLE ATMOSPHERE WILL SUPPORT THE
DEVELOPMENT OF SOME STORMS ALONG THIS BOUNDARY ACROSS ERN
AR...SWRN TN...NWRN MS THIS AFTERNOON. BUMPED UP POPS INTO THE
30-40 PCT RANGE THERE WITH DIMINISHING POPS TO THE EAST. LARGE
DEW POINT DEPRESSIONS AT THE SURFACE AS TEMPERATURES RISE AGAIN
INTO THE LOW 90S MAY LEAD TO GUSTY WINDS WITH SOME OF THESE
STORMS.
LOW PRESSURE WILL BE FORMING OVER OKLAHOMA TONIGHT AND BEGIN TO
TRACK NORTHEAST INTO SOUTHERN MISSOURI THURSDAY MORNING. ROBUST
THUNDERSTORM DEVELOPMENT IS EXPECTED AGAIN TODAY ACROSS OKLAHOMA
WHICH WILL GROW INTO ANOTHER MCS TONIGHT. IT REMAINS UNCLEAR HOW
FAR EAST THIS MCS WILL TRACK OVERNIGHT...SOME INDICATIONS SUGGEST
IT MAY REACH EASTERN ARKANSAS LATE. THEREFORE...KEPT MODERATE CHC
POPS ACROSS THAT REGION.
WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE MIDSOUTH THURSDAY
AS MID LEVEL HEIGHT FALLS OVERSPREAD A WARM/MOIST WARM SECTOR.
WHILE WIND SHEAR REMAINS LOW AT LEAST EARLY...MODERATELY UNSTABLE
CONDITIONS WILL SUPPORT STORM CLUSTERS CAPABLE OF WIND DAMAGE. THE
RISK OF SEVERE WILL INCREASE BY LATE AFTERNOON AND EVENING ACROSS
THE CENTRAL AND EASTERN AREAS AS THE MID LEVEL FLOW STRENGTHENS
JUST AHEAD OF THE COLD FRONT. MAY SEE MESSY CLUSTERS OF THUNDERSTORMS
EVENTUALLY FORM A SQUALL LINE EAST OF THE MISSISSIPPI RIVER AFTER
21Z-00Z WITH ATTENDANT WIND DAMAGE THREAT. LOW LEVEL FLOW/VEERING
DOES NOT APPEAR SUPPORTIVE FOR TORNADIC DEVELOPMENT SO WILL REMOVE
THAT THREAT FROM THE HWO.
GFS STILL LAGS BACK WITH THE COLD FRONT...WITH ALL OTHER LARGE
SCALE MODELS IN GOOD AGREEMENT DRYING THINGS OUT BY 12Z FRIDAY.
COOLER AND DRIER AIR WILL BRING A REFRESHING FRIDAY WITH HIGHS
ONLY IN THE LOW TO MID 70S AND LOWS FRIDAY NIGHT IN THE UPPER
40S/MID 50S.
.LONG TERM...SATURDAY THROUGH TUESDAY.
WAA RETURNS FOR THE WEEKEND AS A BUILDING RIDGE OVER THE PLAINS
BEGINS TO BUILD EASTWARD. HOWEVER...MODELS HAVE SHIFTED THE RIDGE
AXIS A BIT WESTWARD WITH RECENT RUNS AND NOW KEEPS THE MIDSOUTH IN
A NORTHWEST FLOW WITH A PESKY WEAK FRONT REMAINING IN PLACE.
THUS...SMALL CHANCES FOR THUNDERSTORMS HAVE BEEN INTRODUCED FOR
SUNDAY AND BEYOND. TEMPERATURES STILL LOOK WARM...UPPER 80S TO
LOWER 90S.
BORGHOFF
&&
.AVIATION...
06Z TAF CYCLE
TEMPORARY MVFR CONDITIONS DUE TO PATCHY FOG POSSIBLE AT TUP
BETWEEN 30/09-12Z. OTHERWISE...VFR CONDITIONS EXPECTED TO CONTINUE AT
TAF SITES FOR THE NEXT 24 HOURS. A STALLED OUT SURFACE BOUNDARY
NEARBY COMBINED WITH DAYTIME HEATING ON WEDNESDAY MAY RESULT IN
THE DEVELOPMENT OF ISOLATED PULSE TYPE THUNDERSTORMS MAINLY AFTER
30/19Z AT MEM/JBR/TUP. ADDITIONAL THUNDERSTORMS POSSIBLE WEDNESDAY
NIGHT AT ALL TAF SITES AS THE SURFACE BOUNDARY LIFTS NORTH AS A WARM
FRONT. LIGHT/VARIABLE WINDS WILL BECOME NORTHEAST TO EAST WINDS
BETWEEN 5-7 KTS AND VEERING SOUTHEAST TO SOUTHWEST WEDNESDAY
AFTERNOON AND EVENING.
CJC
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 93 73 82 56 / 40 30 90 50
MKL 92 66 81 55 / 20 30 80 70
JBR 90 69 77 54 / 40 40 90 30
TUP 93 69 86 58 / 20 20 60 80
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1157 PM CDT TUE MAY 29 2012
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION...FOR 06Z AVIATION DISCUSSION.
LIFR FOG VSBYS CKV PER LEFT OVER MOISTURE FROM EVENING SHWR/TSTM
ACTIVITY THRU 30/10Z...OTHERWISE SOME MVFR FOG CSV PER LOW LEVEL
MOISTURE POOLING THRU 30/12Z. EXPECT WEAK RIDGING INFLUENCES SFC
AND ALOFT AND QUASI STATIONARY SFC FRONT TO PROVIDE FOR AT LEAST
SCT CU/BKN AC BY 30/18Z. ISO SHWRS/TSTMS POSSIBLE...BUT COVERAGE
SHOULD BE ISO AT BEST AND WILL NOT MENTION AT TAF SITES AS OF THIS
TIME. DIURNAL INFLUENCES SHOULD DISSIPATE BY 31/02Z WITH SCT AC
REMAINING.
&&
.PREV DISCUSSION.../ISSUED 704 PM CDT TUE MAY 29 2012/
UPDATE...
FRONTAL BOUNDARY POSITIONED JUST NORTH OF THE MID STATE AT 21Z.
THIS FEATURE IS EXPECTED TO MOVE THROUGH OVERNIGHT. RUC AND WRF SOLUTIONS
DO NOT SHOW ANY REDEVELOPMENT BEHIND THE CURRENT ACTIVITY WHICH
ROUGHLY COVERS THE SOUTHERN HALF OF THE CWA. WILL THEREFORE BEGIN
TO REMOVE POPS ACROSS OUR NORTHERN COUNTIES.
OTW...THE CURRENT ACTIVITY ACROSS THE SOUTH HAS WEAKENED. LAPS
DATA SHOWED CAPES APPROACHING 3,000 J/KG ACROSS NORTHWESTERN AREAS
WHEN THE TSTM WIND DMG WAS ONGOING. CURRENTLY...CAPES ARE 2400 MAX
ACROSS SOUTHWESTERN ZONES. SO ALL IN ALL...IT IS DOUBTFUL THAT
MORE SEVERE WX WILL OCCUR. I WILL HOWEVER...BOOST POPS TO 50
PERCENT ACROSS SOUTHERN ZONES FOR THIS EVENING.
THE PRECIP SHOULD END BY 06Z.
UPDATE OUT SHORTLY.
PREV DISCUSSION.../ISSUED 639 PM CDT TUE MAY 29 2012/
AVIATION 00Z DISCUSSION...
FRONTAL BOUNDARY TO CONTINUE PUSHING ACROSS THE MID STATE THIS
EVENING. DRIER AIR WILL INFILTRATE THE REGION FROM NW TO SE AND
PUT AN END TO THE CONVECTION BY 06Z FOR THE CSV AREA. OTW...WILL
SEE SOME LATE NIGHT FOG DEVELOPMENT...ESPECIALLY ACROSS THE CSV
AREA WHERE VSBYS OF 1-3 SM WILL BE COMMON BY 12Z.
DRY WEATHER EXPECTED ON WEDNESDAY WITH SOME FEW/SCT AFT CU.
PREV DISCUSSION.../ISSUED 251 PM CDT TUE MAY 29 2012/
DISCUSSION...MAIN CONCERNS FOR THIS FORECAST PERIOD ARE
THUNDERSTORM AND SEVERE WX PROBABILITIES...THIS AFTERNOON AND
EVENING...AND ESPECIALLY FOR LATE THURSDAY INTO EARLY FRIDAY.
AT MID AFTERNOON...SCATTERED THUNDERSTORMS WERE OBSERVED OVER THE
PLATEAU...AND MORE THUNDERSTORMS WERE DEVELOPING OVER WEST KY JUST
AHEAD OF A COLD FRONT. ADDITIONAL THUNDERSTORM DEVELOPMENT IS
EXPECTED LATE THIS AFTERNOON THROUGH THE EVENING AS THE FRONT
PUSHES INTO THE WARM AND HUMID AIR ACROSS MID TN. WIDESPREAD
SEVERE WX IS NOT EXPECTED...BUT A FEW STORMS MAY BECOME BRIEFLY
SEVERE WITH LOCALIZED STRONG WIND GUSTS AND VERY HEAVY DOWNPOURS.
THE ACTIVITY SHOULD SETTLE DOWN BY MIDNIGHT. THE OVERNIGHT SETUP
APPEARS PRETTY GOOD FOR SOME PATCHES OF DENSE FOG AS SURFACE WINDS
BECOME LIGHT.
ON WEDNESDAY...THE ATMOSPHERE WILL BECOME DRIER OVER MID TN...BUT WITH
FAIRLY STEEP MID LEVEL LAPSE RATES AND A COUPLE OF WEAK
IMPULSES...ISOLATED THUNDERSTORMS CANNOT BE RULED OUT. SOUNDING
PROFILES SUGGEST POTENTIAL FOR SOME MARGINAL SEVERE HAIL ON
WEDNESDAY IF ANY STRONG UPDRAFTS ARE ABLE TO DEVELOP. TEMPERATURES
ARE EXPECTED TO BE SIMILAR TO TODAY...BUT HUMIDITY LEVELS WILL BE
DOWN SLIGHTLY.
LOOKING AHEAD TO THURSDAY THROUGH FRIDAY...AN USUALLY DEEP LOW
PRESSURE SYSTEM FOR THIS TIME OF YEAR WILL CROSS THE REGION.
THUNDERSTORMS WILL BECOME LIKELY...ESPECIALLY THURSDAY NIGHT. SPC
HAS THE AREA IN A SLIGHT RISK WITH THE MAIN CONCERNS BEING
DAMAGING WINDS AND LARGE HAIL. HEAVY DOWNPOURS SHOULD ALSO BE
EXPECTED. WE WILL HAVE TO WAIT AND SEE HOW ALL THE INGREDIENTS
COME TOGETHER...BUT A SIGNIFICANT OUTBREAK OF SEVERE STORMS WITH
SOME TORNADO POTENTIAL CANNOT BE RULED OUT WITH THIS TYPE OF
SYSTEM.
SHOWERS AND STORMS WILL DIMINISH ON FRIDAY AS MUCH COOLER AND
DRIER AIR MOVES IN. WE WILL HAVE A COUPLE OF COOLER THAN NORMAL
DAYS...WHICH IS PRETTY RARE IN RECENT HISTORY. THE COOL PERIOD WILL
BE BRIEF. RISING HEIGHTS WILL PUMP TEMPERATURES UP AGAIN WELL INTO
THE 80S SUNDAY AND SOME 90S FOR MONDAY. DRY CONDITIONS ARE
EXPECTED FRIDAY NIGHT INTO SATURDAY...BUT THE THREAT FOR AT LEAST
ISOLATED STORMS WILL RETURN AFTER THAT AS A WARM ADVECTION REGIME
DEVELOPS...THEN THE AREA GETS ON THE FRINGE OF NW UPPER LEVEL
FLOW (MCS PATTERN).
13
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1202 PM CDT WED MAY 30 2012
.UPDATE...
WE HAVE UPDATED FOR HIGHER THUNDER CHANCES FURTHER WEST TO ABOUT
THE EDGE OF THE CAPROCK THIS AFTERNOON...AND ALSO MENTIONED SEVERE
THREAT. MAJORITY OF SOLUTIONS NOW INDICATE THAT THUNDERSTORM
SHOULD DEVELOP THIS AFTERNOON ROUGHLY SILVERTON TO DOUGHERTY LINE
AS LOW LEVEL SOUTHEAST FLOW SHOULD PILE UP ON EDGE OF THE CAPROCK.
STRONG SURFACE HEATING ALONG WITH A WEAK APPROACHING DISTURBANCE
IN THE WEST-NORTHWEST FLOW ALOFT PROVIDING ADDITIONAL FORCING.
MIXED LAYER CAPES APPEAR ADEQUATE FOR WIND AND LARGE HAIL THREAT
THIS AREA...LIFTED CONDENSATION LEVELS HOWEVER APPEAR A BIT HIGH
FOR SIGNIFICANT TORNADO THREAT. AFTERNOON HODOGRAPHS INDICATE
MORE A SPLITTING SUPERCELL THREAT...THOUGH LOWER LEVELS SHOULD
LENGTHEN THIS EVENING. THERE MAY BE A FEW MORE STORMS ARRIVING IN
NORTHWEST FLOW THROUGH THE SOUTHERN PANHANDLE DURING THE EARLY
EVENING WITH THOSE LONGER HODOGRAPHS THEN SOMETHING TO CONSIDER.
ANYWAY...AREAS FURTHER WEST ON THE CAPROCK LIKELY TO REMAIN HOT
AND DRY WITH SURFACE LOW EDGING GRADUALLY TO THE WEST FAVORING THE
DOWNSLOPE COMPONENT. RMCQUEEN
&&
.AVIATION...
VFR AND DRY AT KLBB EARLY. OUTFLOW/FRONT EXPECTED TO PASS THROUGH
KLBB DURING THE EVENING WITH A RISK OF AT LEAST MVFR CIG LATER
TONIGHT. WEST OF KCDS LATER TODAY...THUNDER EXPECTED TO DEVELOP
AND DRIFT EAST INTO OR CLOSE TO KCDS LATE IN THE AFTERNOON WITH
POSSIBILITY OF SEVERE STORMS AS WELL. PREVIOUS TAF INDICATED GR
AND WE WILL CONTINUE. KCDS COULD SEE ANOTHER CHANCE OF THUNDER
DURING THE EARLY EVENING IF ACTIVITY EDGES IN THROUGH THE SOUTHERN
PANHANDLE IN DEVELOPING NORTHWEST FLOW ALOFT. WINDS TURNING MORE
TO THE NORTHEAST OVERNIGHT SHOULD BRING IN AN IFR OR MVFR CLOUD
LAYER THAT MAY PERSIST THROUGH MUCH OF THURSDAY MORNING. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 654 AM CDT WED MAY 30 2012/
AVIATION...
GREATEST FLIGHT COMPLICATIONS WILL UNFOLD AT CDS DURING THE NEXT 24
HRS. INITIAL THREAT IS FOR MVFR STRATUS DEVELOPMENT IN THE WAKE OF
AN OUTFLOW BOUNDARY WEST OF THE TERMINAL...BUT LOW CLOUDS THUS FAR
HAVE FAILED TO DEVELOP CLOSER THAN 50 MILES NORTHWEST OF CDS. WILL
THEREFORE KEEP MENTION OUT OF THE TAF. NEXT CHALLENGE IS TSRA
POTENTIAL. MODELS AS A WHOLE HAVE NOT HAD A GOOD HANDLE ON TSRA
OVERNIGHT EAST OF CDS OR THE REMNANT BOUNDARIES LEFT BEHIND...BUT
OVERALL PATTERN BY THIS AFTN IS SUPPORTIVE OF ISO-SCT TSRA
DEVELOPMENT NEAR A SURFACE LOW AND DRYLINE EXPECTED TO BE JUST
WEST OF CDS BY PEAK HEATING. WITH STRONG INSTABILITY
FORECAST BY THE LATEST SHORT-TERM MODELS...HAVE ISOLATED A CRUDE
2-HOUR WINDOW OF TSRAGR ON STATION AT CDS FROM 22Z-00Z TO DRAW
ATTN TO THIS ENHANCED THREAT. BY TONIGHT...STRATUS IS SHOWN TO HAVE
A BETTER CHANCE OF DEVELOPMENT FOLLOWING COLD FROPA.
ONLY THREAT TO LBB IS THE RESULT OF AN ELEVATED SMOKE LAYER THAT
IS ONCE AGAIN EXPECTED TO MIX DOWN BY LATE AFTN/EARLY EVNG LIKELY
REDUCING VISBYS TO LOW VFR/HIGH MVFR LEVELS. EXPECT VISBYS TO
RECOVER MARKEDLY SHORTLY AFTER SUNSET. COLD FROPA LATER TONIGHT
COULD STIR UP A FEW LOW CLOUDS...BUT THE BEST CHANCE OF THIS
APPEARS TO BE CLOSER TO 31/12Z.
PREV DISCUSSION... /ISSUED 405 AM CDT WED MAY 30 2012/
SHORT TERM...
INGREDIENTS ARE COMING TOGETHER FOR A POTENTIALLY ACTIVE BOUT OF
THUNDERSTORMS LATER TODAY FOR A PORTION OF OUR COUNTY WARNING AREA.
MUCH OF THIS POTENTIAL HINGES ON A WELL-DEFINED OUTFLOW BOUNDARY
THAT HAS ALREADY ENTERED OUR FAR NERN COUNTIES EARLY THIS MORNING
AHEAD OF 15-25 MPH EASTERLY WINDS. THIS BOUNDARY IS COURTESY OF A
SERIES OF NOCTURNAL STORMS IN OKLAHOMA WHICH UNFORTUNATELY WERE NOT
HANDLED WELL AT ALL BY 00Z MODELS. GIVEN THIS OVERSIGHT BY THE
MODELS...THIS FORECAST IS THE RECIPIENT OF A RESPECTABLE DOSE OF
SOUTH PLAINS SVR WX CLIMATOLOGY AND PATTERN RECOGNITION.
THE OUTFLOW BOUNDARY SHOULD BEGIN STALLING LATER THIS MORNING
ROUGHLY NEAR A SILVERTON TO GUTHRIE LINE AT WHICH TIME A WEAK
SURFACE LOW NEAR CLOVIS WILL MOVE SLOWLY EASTWARD. MUCH OF THIS
EASTWARD PUSH WILL BE DUE TO DIURNAL MIXING IN VERY DRY AIR...BUT
SOME CONTRIBUTION CAN BE TRACED TO A NEARBY MINOR S/W TROF EMBEDDED
IN W-NWLY FLOW ALOFT. THE DRYLINE WILL LIKELY SHARPEN JUST OFF THE
CAPROCK BY MIDDAY AND INTERSECT THE OUTFLOW BDRY AND NEARBY SURFACE
LOW SOMEWHERE IN THE FAR SERN TX PANHANDLE OR NRN ROLLING PLAINS. IT
IS WORTH NOTING THAT THE NSSL-WRF AND RECENT RUNS OF THE HRRR ARE
QUITE AGGRESSIVE IN KEEPING THE OUTFLOW BDRY IN PLACE BY MID-AFTN
WITH A TEXTBOOK DRYLINE BULGE FORECAST TO DEVELOP NORTHEAST OF
LUBBOCK. AM INCLINED TO BELIEVE THE DRYLINE WILL MAKE AMPLE HEADWAY
INTO THE ROLLING PLAINS...BUT FAIL TO OVERWHELM DEEP MOISTURE ON THE
COOL SIDE OF THE OUTFLOW BDRY. ADD TO THIS A LFQ OF AN UPPER JET
MAXIMUM AND LIFT SHOULD BE MORE THAN SUFFICIENT FOR CI NEAR/SHORTLY
AFTER PEAK HEATING. SUGGESTED EXTREME CAPE ALONE PER THE HRRR AND
NSSL-WRF WARRANT SEVERE MENTION IN THE GRIDS. OF ADDITIONAL CONCERN
IS THE NW-SE ORIENTED OUTFLOW BDRY WHICH MAY INSPIRE ISOLATED
OCCURRENCES OF TORNADOES. THIS THREAT WILL BE ADDRESSED IN THE HWO.
NEEDLESS TO SAY...THIS SETUP WILL BE CLOSELY MONITORED THROUGHOUT
THE DAY.
AS THE S/W TROF PASSES THIS EVENING...A COLD FRONT WILL ACCELERATE
SOUTH FROM WRN KANSAS BEFORE OVERTAKING THE SOUTH PLAINS THU MRNG. A
PRE-FRONTAL WIND SHIFT WILL OCCUR LOCALLY OVERNIGHT...BUT WITH
BACKGROUND ASCENT ON THE DECLINE BEHIND THE S/W TROF...FEEL POPS MAY
HAVE A HARD TIME BEING REALIZED UNTIL THE FRONT APPROACHES LATE IN
THE NIGHT. FOR THIS REASON HAVE KEPT SLIGHT CHANCE POPS ACROSS OUR
NRN TIER OF COUNTIES OVERNIGHT WHERE ELEVATED CAPE MAY BE PUT TO
WORK ONCE LL LIFT INTENSIFIES.
LONG TERM...
FLOW ALOFT WILL COMMENCE TO EVOLVE TO NW FLOW ON THURSDAY...THANKS
TO AN AMPLIFYING UA RIDGE ACROSS THE WESTERN CONUS. FORECAST MODELS
CONTINUE TO HINT AT THREE EMBEDDED DISTURBANCES THE FIRST OF WHICH
IS NOTED ACROSS THE CENTRAL PLAINS LATE TONIGHT/EARLY TOMORROW
MORNING. THIS DISTURBANCE WILL SEND A MODERATELY STRONG BACKDOOR
COLD FRONT ACROSS THE REGION LATE TONIGHT...WHILE THE SECOND
DISTURBANCE NEAR THE HIGH PLAINS WILL USHER IN A SECONDARY STRONGER
FRONTAL PUSH LATE TOMORROW MORNING. MOS GUIDANCE HINTS AT NORTHERLY
SFC WIND SPEEDS OF 20-25 MPH...WHICH IS NOT TOO SURPRISING GIVEN THE
TIGHT PRESSURE GRADIENT THAT IS INDUCED BY A 1018 MB SFC RIDGE NNE
OF THE REGION. WILL THEREFORE EXPECT TO SEE COOLER TEMPS FOR
TOMORROW /MID 70S NW TO MID 80S SE/ AND A GRADUAL WARMUP THEREAFTER.
THE NAM...GFS AND ECMWF SOLUTIONS DISPLAYED RATHER LIGHT QPF VALUES
NEARING THE FAR NORTHERN SOUTH PLAINS TOMORROW MORNING...BUT WITH A
QUICK DIMINISHING LIKELY DUE TO THE DRYER AIR THAT WILL BE
TRANSPORTED SOUTHWARD FROM THE AFOREMENTIONED SFC RIDGE.
FURTHERMORE...FRONTOGENETICAL FORCING IS PROGGED TO BE SIGNIFICANTLY
WEAKER BY TOMORROW MORNING AND THUS LOW TO MID LEVEL CLOUDINESS WILL
BE THE RULE /KEEPING POPS BELOW MENTIONABLE/. CONCURRENTLY...THE
THIRD DISTURBANCE IS SHOWN TO BE A CUTOFF LOW AND IS EXPECTED TO
TRANSLATE SSE ACROSS THE BAJA OF CALIFORNIA BY FRIDAY...GIVING
LITTLE FANFARE FOR THE FA.
NW FLOW WILL BEGIN TO WEAKEN ON FRIDAY AND SOUTHERLY FLOW WILL
RETURN TO THE SOUTH PLAINS DUE TO THE AFOREMENTIONED SFC RIDGE
SHIFTING TO THE SOUTHEAST AND AS A RESULT...SFC WINDS VEERING TO A
MORE SOUTHERLY COMPONENT. MODEL RUNS EXHIBIT STORMS FROM THE HIGHER
ELEVATIONS TO SLIDE SOUTHEAST TOWARDS THE SOUTHERN TEXAS PANHANDLE
ON FRIDAY. THE GFS IS QUITE BULLISH IN SHOWING THIS IN ADDITION TO
PRECIP NEAR THE TEXAS/NEW MEXICO STATE LINE...COINCIDING WITH THE
BEST MOISTURE AXIS. THE NAM AND ECMWF SOLUTIONS ARE MUCH MORE
PESSIMISTIC...WITH ONLY RATHER LIGHT QPF SIGNALS ACROSS THE
PANHANDLES. IT IS NOT UNUSUAL FOR STORMS TO DRIFT FROM HIGHER
ELEVATIONS AND TOWARDS THE CWA UNDER THE INFLUENCE OF NW FLOW
ALOFT...HOWEVER DESPITE THE BULLISH BEHAVIOR PORTRAYED FROM THE
GFS...IT AND NAM AND ECMWF SOLUTIONS MAINTAIN THE BEST PRECIP ACROSS
PANHANDLES. WILL OPT TO INCREASE POPS TO BETWEEN 10-14 PERCENT
ACROSS THE FAR NORTHERN AND WESTERN ZONES...THUS BELOW MENTIONABLE
LEVELS ATTM.
THROUGH THE WEEKEND...UA RIDGING WILL PROGRESS EASTWARD ACROSS THE
SOUTHERN PLAINS...AS A COUPLE OF EMBEDDED IMPULSES MOVES ACROSS THE
REGION FROM NEW MEXICO SATURDAY NIGHT AND SUNDAY EVENING. KEEPING
IN MIND THAT ON SATURDAY THE FLOW ALOFT IS UNDER THE INFLUENCE OF
WEAK NWLY FLOW...THE FIRST IMPULSE APPEAR TO SPARK STORMS ACROSS
THE SERN TEXAS PANHANDLE AND EASTERN ZONES...AS THE TRANSPORT OF
GULF MOISTURE INDUCE DEWPOINTS IN THE 50S AND 60S. HENCE PROGGED
PWATS NEARING 1.70 INCHES...A WEAK CAP AND SLIGHT SYNOPTIC LIFT
CAN NOT BE IGNORED. HAVE THEREFORE INTRODUCED POPS ACROSS THE
AFOREMENTIONED AREAS SATURDAY EVENING AND NIGHT. THE SECOND IMPULSE
WILL CREATE THE RETURN OF THE SLOSHING DRYLINE...WHICH IS SHOWN TO
RESIDE ACROSS THE REGION THROUGH MID-WEEK NEXT WEEK...AS FLOW ALOFT
EVOLVES TO SW FLOW DUE TO AN INCOMING PACIFIC UA LOW. THE CAP
APPEARS RELATIVELY STRONG AS THE GFS IS VOID OF PRECIP DESPITE A
LINGERING DRYLINE...VERSUS SIGNALS OF PRECIP ALONG THE DRYLINE EACH
EVENING PER THE ECMWF. WILL MAINTAIN SILENT POPS BEYOND SATURDAY
NIGHT ATTM...AND WILL CONTINUE TO ANALYZE FUTURE MODEL RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 91 57 76 52 83 / 0 20 10 10 10
TULIA 94 59 77 53 83 / 10 20 10 10 10
PLAINVIEW 98 60 78 54 83 / 0 20 10 10 10
LEVELLAND 98 62 81 55 85 / 0 10 10 10 10
LUBBOCK 99 63 81 55 84 / 0 10 10 10 10
DENVER CITY 98 61 83 56 86 / 0 10 10 10 10
BROWNFIELD 99 63 82 56 85 / 0 10 10 10 10
CHILDRESS 97 65 83 57 83 / 20 50 10 10 10
SPUR 102 63 83 57 86 / 20 20 10 10 10
ASPERMONT 102 66 85 57 87 / 10 30 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99/05
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
654 AM CDT WED MAY 30 2012
.AVIATION...
GREATEST FLIGHT COMPLICATIONS WILL UNFOLD AT CDS DURING THE NEXT 24
HRS. INITIAL THREAT IS FOR MVFR STRATUS DEVELOPMENT IN THE WAKE OF
AN OUTFLOW BOUNDARY WEST OF THE TERMINAL...BUT LOW CLOUDS THUS FAR
HAVE FAILED TO DEVELOP CLOSER THAN 50 MILES NORTHWEST OF CDS. WILL
THEREFORE KEEP MENTION OUT OF THE TAF. NEXT CHALLENGE IS TSRA
POTENTIAL. MODELS AS A WHOLE HAVE NOT HAD A GOOD HANDLE ON TSRA
OVERNIGHT EAST OF CDS OR THE REMNANT BOUNDARIES LEFT BEHIND...BUT
OVERALL PATTERN BY THIS AFTN IS SUPPORTIVE OF ISO-SCT TSRA
DEVELOPMENT NEAR A SURFACE LOW AND DRYLINE EXPECTED TO BE JUST
WEST OF CDS BY PEAK HEATING. WITH STRONG INSTABILITY
FORECAST BY THE LATEST SHORT-TERM MODELS...HAVE ISOLATED A CRUDE
2-HOUR WINDOW OF TSRAGR ON STATION AT CDS FROM 22Z-00Z TO DRAW
ATTN TO THIS ENHANCED THREAT. BY TONIGHT...STRATUS IS SHOWN TO HAVE
A BETTER CHANCE OF DEVELOPMENT FOLLOWING COLD FROPA.
ONLY THREAT TO LBB IS THE RESULT OF AN ELEVATED SMOKE LAYER THAT
IS ONCE AGAIN EXPECTED TO MIX DOWN BY LATE AFTN/EARLY EVNG LIKELY
REDUCING VISBYS TO LOW VFR/HIGH MVFR LEVELS. EXPECT VISBYS TO
RECOVER MARKEDLY SHORTLY AFTER SUNSET. COLD FROPA LATER TONIGHT
COULD STIR UP A FEW LOW CLOUDS...BUT THE BEST CHANCE OF THIS
APPEARS TO BE CLOSER TO 31/12Z.
&&
.PREV DISCUSSION... /ISSUED 405 AM CDT WED MAY 30 2012/
SHORT TERM...
INGREDIENTS ARE COMING TOGETHER FOR A POTENTIALLY ACTIVE BOUT OF
THUNDERSTORMS LATER TODAY FOR A PORTION OF OUR COUNTY WARNING AREA.
MUCH OF THIS POTENTIAL HINGES ON A WELL-DEFINED OUTFLOW BOUNDARY
THAT HAS ALREADY ENTERED OUR FAR NERN COUNTIES EARLY THIS MORNING
AHEAD OF 15-25 MPH EASTERLY WINDS. THIS BOUNDARY IS COURTESY OF A
SERIES OF NOCTURNAL STORMS IN OKLAHOMA WHICH UNFORTUNATELY WERE NOT
HANDLED WELL AT ALL BY 00Z MODELS. GIVEN THIS OVERSIGHT BY THE
MODELS...THIS FORECAST IS THE RECIPIENT OF A RESPECTABLE DOSE OF
SOUTH PLAINS SVR WX CLIMATOLOGY AND PATTERN RECOGNITION.
THE OUTFLOW BOUNDARY SHOULD BEGIN STALLING LATER THIS MORNING
ROUGHLY NEAR A SILVERTON TO GUTHRIE LINE AT WHICH TIME A WEAK
SURFACE LOW NEAR CLOVIS WILL MOVE SLOWLY EASTWARD. MUCH OF THIS
EASTWARD PUSH WILL BE DUE TO DIURNAL MIXING IN VERY DRY AIR...BUT
SOME CONTRIBUTION CAN BE TRACED TO A NEARBY MINOR S/W TROF EMBEDDED
IN W-NWLY FLOW ALOFT. THE DRYLINE WILL LIKELY SHARPEN JUST OFF THE
CAPROCK BY MIDDAY AND INTERSECT THE OUTFLOW BDRY AND NEARBY SURFACE
LOW SOMEWHERE IN THE FAR SERN TX PANHANDLE OR NRN ROLLING PLAINS. IT
IS WORTH NOTING THAT THE NSSL-WRF AND RECENT RUNS OF THE HRRR ARE
QUITE AGGRESSIVE IN KEEPING THE OUTFLOW BDRY IN PLACE BY MID-AFTN
WITH A TEXTBOOK DRYLINE BULGE FORECAST TO DEVELOP NORTHEAST OF
LUBBOCK. AM INCLINED TO BELIEVE THE DRYLINE WILL MAKE AMPLE HEADWAY
INTO THE ROLLING PLAINS...BUT FAIL TO OVERWHELM DEEP MOISTURE ON THE
COOL SIDE OF THE OUTFLOW BDRY. ADD TO THIS A LFQ OF AN UPPER JET
MAXIMUM AND LIFT SHOULD BE MORE THAN SUFFICIENT FOR CI NEAR/SHORTLY
AFTER PEAK HEATING. SUGGESTED EXTREME CAPE ALONE PER THE HRRR AND
NSSL-WRF WARRANT SEVERE MENTION IN THE GRIDS. OF ADDITIONAL CONCERN
IS THE NW-SE ORIENTED OUTFLOW BDRY WHICH MAY INSPIRE ISOLATED
OCCURRENCES OF TORNADOES. THIS THREAT WILL BE ADDRESSED IN THE HWO.
NEEDLESS TO SAY...THIS SETUP WILL BE CLOSELY MONITORED THROUGHOUT
THE DAY.
AS THE S/W TROF PASSES THIS EVENING...A COLD FRONT WILL ACCELERATE
SOUTH FROM WRN KANSAS BEFORE OVERTAKING THE SOUTH PLAINS THU MRNG. A
PRE-FRONTAL WIND SHIFT WILL OCCUR LOCALLY OVERNIGHT...BUT WITH
BACKGROUND ASCENT ON THE DECLINE BEHIND THE S/W TROF...FEEL POPS MAY
HAVE A HARD TIME BEING REALIZED UNTIL THE FRONT APPROACHES LATE IN
THE NIGHT. FOR THIS REASON HAVE KEPT SLIGHT CHANCE POPS ACROSS OUR
NRN TIER OF COUNTIES OVERNIGHT WHERE ELEVATED CAPE MAY BE PUT TO
WORK ONCE LL LIFT INTENSIFIES.
LONG TERM...
FLOW ALOFT WILL COMMENCE TO EVOLVE TO NW FLOW ON THURSDAY...THANKS
TO AN AMPLIFYING UA RIDGE ACROSS THE WESTERN CONUS. FORECAST MODELS
CONTINUE TO HINT AT THREE EMBEDDED DISTURBANCES THE FIRST OF WHICH
IS NOTED ACROSS THE CENTRAL PLAINS LATE TONIGHT/EARLY TOMORROW
MORNING. THIS DISTURBANCE WILL SEND A MODERATELY STRONG BACKDOOR
COLD FRONT ACROSS THE REGION LATE TONIGHT...WHILE THE SECOND
DISTURBANCE NEAR THE HIGH PLAINS WILL USHER IN A SECONDARY STRONGER
FRONTAL PUSH LATE TOMORROW MORNING. MOS GUIDANCE HINTS AT NORTHERLY
SFC WIND SPEEDS OF 20-25 MPH...WHICH IS NOT TOO SURPRISING GIVEN THE
TIGHT PRESSURE GRADIENT THAT IS INDUCED BY A 1018 MB SFC RIDGE NNE
OF THE REGION. WILL THEREFORE EXPECT TO SEE COOLER TEMPS FOR
TOMORROW /MID 70S NW TO MID 80S SE/ AND A GRADUAL WARMUP THEREAFTER.
THE NAM...GFS AND ECMWF SOLUTIONS DISPLAYED RATHER LIGHT QPF VALUES
NEARING THE FAR NORTHERN SOUTH PLAINS TOMORROW MORNING...BUT WITH A
QUICK DIMINISHMENT LIKELY DUE TO THE DRYER AIR THAT WILL BE
TRANSPORTED SOUTHWARD FROM THE AFOREMENTIONED SFC RIDGE.
FURTHERMORE...FRONTOGENETICAL FORCING IS PROGGED TO BE SIGNIFICANTLY
WEAKER BY TOMORROW MORNING AND THUS LOW TO MID LEVEL CLOUDINESS WILL
BE THE RULE /KEEPING POPS BELOW MENTIONABLE/. CONCURRENTLY...THE
THIRD DISTURBANCE IS SHOWN TO BE A CUTOFF LOW AND IS EXPECTED TO
TRANSLATE SSE ACROSS THE BAJA OF CALIFORNIA BY FRIDAY...GIVING
LITTLE FANFARE FOR THE FA.
NW FLOW WILL BEGIN TO WEAKEN ON FRIDAY AND SOUTHERLY FLOW WILL
RETURN TO THE SOUTH PLAINS DUE TO THE AFOREMENTIONED SFC RIDGE
SHIFTING TO THE SOUTHEAST AND AS A RESULT...SFC WINDS VEERING TO A
MORE SOUTHERLY COMPONENT. MODEL RUNS EXHIBIT STORMS FROM THE HIGHER
ELEVATIONS TO SLIDE SOUTHEAST TOWARDS THE SOUTHERN TEXAS PANHANDLE
ON FRIDAY. THE GFS IS QUITE BULLISH IN SHOWING THIS IN ADDITION TO
PRECIP NEAR THE TEXAS/NEW MEXICO STATE LINE...COINCIDING WITH THE
BEST MOISTURE AXIS. THE NAM AND ECMWF SOLUTIONS ARE MUCH MORE
PESSIMISTIC...WITH ONLY RATHER LIGHT QPF SIGNALS ACROSS THE
PANHANDLES. IT IS NOT UNUSUAL FOR STORMS TO DRIFT FROM HIGHER
ELEVATIONS AND TOWARDS THE CWA UNDER THE INFLUENCE OF NW FLOW
ALOFT...HOWEVER DESPITE THE BULLISH BEHAVIOR PORTRAYED FROM THE
GFS...IT AND NAM AND ECMWF SOLUTIONS MAINTAIN THE BEST PRECIP ACROSS
PANHANDLES. WILL OPT TO INCREASE POPS TO BETWEEN 10-14 PERCENT
ACROSS THE FAR NORTHERN AND WESTERN ZONES...THUS BELOW MENTIONABLE
LEVELS ATTM.
THROUGH THE WEEKEND...UA RIDGING WILL PROGRESS EASTWARD ACROSS THE
SOUTHERN PLAINS...AS A COUPLE OF EMBEDDED IMPULSES MOVES ACROSS THE
REGION FROM NEW MEXICO SATURDAY NIGHT AND SUNDAY EVENING. KEEPING
IN MIND THAT ON SATURDAY THE FLOW ALOFT IS UNDER THE INFLUENCE OF
WEAK NWLY FLOW...THE FIRST IMPULSE APPEAR TO SPARK STORMS ACROSS
THE SERN TEXAS PANHANDLE AND EASTERN ZONES...AS THE TRANSPORT OF
GULF MOISTURE INDUCE DEWPOINTS IN THE 50S AND 60S. HENCE PROGGED
PWATS NEARING 1.70 INCHES...A WEAK CAP AND SLIGHT SYNOPTIC LIFT
CAN NOT BE IGNORED. HAVE THEREFORE INTRODUCED POPS ACROSS THE
AFOREMENTIONED AREAS SATURDAY EVENING AND NIGHT. THE SECOND IMPULSE
WILL CREATE THE RETURN OF THE SLOSHING DRYLINE...WHICH IS SHOWN TO
RESIDE ACROSS THE REGION THROUGH MID-WEEK NEXT WEEK...AS FLOW ALOFT
EVOLVES TO SW FLOW DUE TO AN INCOMING PACIFIC UA LOW. THE CAP
APPEARS RELATIVELY STRONG AS THE GFS IS VOID OF PRECIP DESPITE A
LINGERING DRYLINE...VERSUS SIGNALS OF PRECIP ALONG THE DRYLINE EACH
EVENING PER THE ECMWF. WILL MAINTAIN SILENT POPS BEYOND SATURDAY
NIGHT ATTM...AND WILL CONTINUE TO ANALYZE FUTURE MODEL RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 91 57 76 52 83 / 0 20 10 10 10
TULIA 94 59 77 53 83 / 10 20 10 10 10
PLAINVIEW 98 60 78 54 83 / 0 20 10 10 10
LEVELLAND 98 62 81 55 85 / 0 10 10 10 10
LUBBOCK 99 63 81 55 85 / 0 10 10 10 10
DENVER CITY 98 61 83 56 86 / 0 10 10 10 10
BROWNFIELD 99 63 82 56 85 / 0 10 10 10 10
CHILDRESS 97 65 83 57 83 / 30 30 10 10 10
SPUR 102 63 83 57 86 / 0 10 10 10 10
ASPERMONT 102 66 85 57 87 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/29/93
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
405 AM CDT WED MAY 30 2012
.SHORT TERM...
INGREDIENTS ARE COMING TOGETHER FOR A POTENTIALLY ACTIVE BOUT OF
THUNDERSTORMS LATER TODAY FOR A PORTION OF OUR COUNTY WARNING AREA.
MUCH OF THIS POTENTIAL HINGES ON A WELL-DEFINED OUTFLOW BOUNDARY
THAT HAS ALREADY ENTERED OUR FAR NERN COUNTIES EARLY THIS MORNING
AHEAD OF 15-25 MPH EASTERLY WINDS. THIS BOUNDARY IS COURTESY OF A
SERIES OF NOCTURNAL STORMS IN OKLAHOMA WHICH UNFORTUNATELY WERE NOT
HANDLED WELL AT ALL BY 00Z MODELS. GIVEN THIS OVERSIGHT BY THE
MODELS...THIS FORECAST IS THE RECIPIENT OF A RESPECTABLE DOSE OF
SOUTH PLAINS SVR WX CLIMATOLOGY AND PATTERN RECOGNITION.
THE OUTFLOW BOUNDARY SHOULD BEGIN STALLING LATER THIS MORNING
ROUGHLY NEAR A SILVERTON TO GUTHRIE LINE AT WHICH TIME A WEAK
SURFACE LOW NEAR CLOVIS WILL MOVE SLOWLY EASTWARD. MUCH OF THIS
EASTWARD PUSH WILL BE DUE TO DIURNAL MIXING IN VERY DRY AIR...BUT
SOME CONTRIBUTION CAN BE TRACED TO A NEARBY MINOR S/W TROF EMBEDDED
IN W-NWLY FLOW ALOFT. THE DRYLINE WILL LIKELY SHARPEN JUST OFF THE
CAPROCK BY MIDDAY AND INTERSECT THE OUTFLOW BDRY AND NEARBY SURFACE
LOW SOMEWHERE IN THE FAR SERN TX PANHANDLE OR NRN ROLLING PLAINS. IT
IS WORTH NOTING THAT THE NSSL-WRF AND RECENT RUNS OF THE HRRR ARE
QUITE AGGRESSIVE IN KEEPING THE OUTFLOW BDRY IN PLACE BY MID-AFTN
WITH A TEXTBOOK DRYLINE BULGE FORECAST TO DEVELOP NORTHEAST OF
LUBBOCK. AM INCLINED TO BELIEVE THE DRYLINE WILL MAKE AMPLE HEADWAY
INTO THE ROLLING PLAINS...BUT FAIL TO OVERWHELM DEEP MOISTURE ON THE
COOL SIDE OF THE OUTFLOW BDRY. ADD TO THIS A LFQ OF AN UPPER JET
MAXIMUM AND LIFT SHOULD BE MORE THAN SUFFICIENT FOR CI NEAR/SHORTLY
AFTER PEAK HEATING. SUGGESTED EXTREME CAPE ALONE PER THE HRRR AND
NSSL-WRF WARRANT SEVERE MENTION IN THE GRIDS. OF ADDITIONAL CONCERN
IS THE NW-SE ORIENTED OUTFLOW BDRY WHICH MAY INSPIRE ISOLATED
OCCURRENCES OF TORNADOES. THIS THREAT WILL BE ADDRESSED IN THE HWO.
NEEDLESS TO SAY...THIS SETUP WILL BE CLOSELY MONITORED THROUGHOUT
THE DAY.
AS THE S/W TROF PASSES THIS EVENING...A COLD FRONT WILL ACCELERATE
SOUTH FROM WRN KANSAS BEFORE OVERTAKING THE SOUTH PLAINS THU MRNG. A
PRE-FRONTAL WIND SHIFT WILL OCCUR LOCALLY OVERNIGHT...BUT WITH
BACKGROUND ASCENT ON THE DECLINE BEHIND THE S/W TROF...FEEL POPS MAY
HAVE A HARD TIME BEING REALIZED UNTIL THE FRONT APPROACHES LATE IN
THE NIGHT. FOR THIS REASON HAVE KEPT SLIGHT CHANCE POPS ACROSS OUR
NRN TIER OF COUNTIES OVERNIGHT WHERE ELEVATED CAPE MAY BE PUT TO
WORK ONCE LL LIFT INTENSIFIES.
&&
.LONG TERM...
FLOW ALOFT WILL COMMENCE TO EVOLVE TO NW FLOW ON THURSDAY...THANKS
TO AN AMPLIFYING UA RIDGE ACROSS THE WESTERN CONUS. FORECAST MODELS
CONTINUE TO HINT AT THREE EMBEDDED DISTURBANCES THE FIRST OF WHICH
IS NOTED ACROSS THE CENTRAL PLAINS LATE TONIGHT/EARLY TOMORROW
MORNING. THIS DISTURBANCE WILL SEND A MODERATELY STRONG BACKDOOR
COLD FRONT ACROSS THE REGION LATE TONIGHT...WHILE THE SECOND
DISTURBANCE NEAR THE HIGH PLAINS WILL USHER IN A SECONDARY STRONGER
FRONTAL PUSH LATE TOMORROW MORNING. MOS GUIDANCE HINTS AT NORTHERLY
SFC WIND SPEEDS OF 20-25 MPH...WHICH IS NOT TOO SURPRISING GIVEN THE
TIGHT PRESSURE GRADIENT THAT IS INDUCED BY A 1018 MB SFC RIDGE NNE
OF THE REGION. WILL THEREFORE EXPECT TO SEE COOLER TEMPS FOR
TOMORROW /MID 70S NW TO MID 80S SE/ AND A GRADUAL WARMUP THEREAFTER.
THE NAM...GFS AND ECMWF SOLUTIONS DISPLAYED RATHER LIGHT QPF VALUES
NEARING THE FAR NORTHERN SOUTH PLAINS TOMORROW MORNING...BUT WITH A
QUICK DIMINISHMENT LIKELY DUE TO THE DRYER AIR THAT WILL BE
TRANSPORTED SOUTHWARD FROM THE AFOREMENTIONED SFC RIDGE.
FURTHERMORE...FRONTEGENTICAL FORCING IS PROGGED TO BE SIGNIFICANTLY
WEAKER BY TOMORROW MORNING AND THUS LOW TO MID LEVEL CLOUDINESS WILL
BE THE RULE /KEEPING POPS BELOW MENTIONABLE/. CONCURRENTLY...THE
THIRD DISTURBANCE IS SHOWN TO BE A CUTOFF LOW AND IS EXPECTED TO
TRANSLATE SSE ACROSS THE BAJA OF CALIFORNIA BY FRIDAY...GIVING
LITTLE FANFARE FOR THE FA.
NW FLOW WILL BEGIN TO WEAKEN ON FRIDAY AND SOUTHERLY FLOW WILL
RETURN TO THE SOUTH PLAINS DUE TO THE AFOREMENTIONED SFC RIDGE
SHIFTING TO THE SOUTHEAST AND AS A RESULT...SFC WINDS VEERING TO A
MORE SOUTHERLY COMPONENT. MODEL RUNS EXHIBIT STORMS FROM THE HIGHER
ELEVATIONS TO SLIDE SOUTHEAST TOWARDS THE SOUTHERN TEXAS PANHANDLE
ON FRIDAY. THE GFS IS QUITE BULLISH IN SHOWING THIS IN ADDITION TO
PRECIP NEAR THE TEXAS/NEW MEXICO STATE LINE...COINCIDING WITH THE
BEST MOISTURE AXIS. THE NAM AND ECMWF SOLUTIONS ARE MUCH MORE
PESSIMISTIC...WITH ONLY RATHER LIGHT QPF SIGNALS ACROSS THE
PANHANDLES. IT IS NOT UNUSUAL FOR STORMS TO DRIFT FROM HIGHER
ELEVATIONS AND TOWARDS THE CWA UNDER THE INFLUENCE OF NW FLOW
ALOFT...HOWEVER DESPITE THE BULLISH BEHAVIOR PORTRAYED FROM THE
GFS...IT AND NAM AND ECMWF SOLUTIONS MAINTAIN THE BEST PRECIP ACROSS
PANHANDLES. WILL OPT TO INCREASE POPS TO BETWEEN 10-14 PERCENT
ACROSS THE FAR NORTHERN AND WESTERN ZONES...THUS BELOW MENTIONABLE
LEVELS ATTM.
THROUGH THE WEEKEND...UA RIDGING WILL PROGRESS EASTWARD ACROSS THE
SOUTHERN PLAINS...AS A COUPLE OF EMBEDDED IMPULSES MOVES ACROSS THE
REGION FROM NEW MEXICO SATURDAY NIGHT AND SUNDAY EVENING. KEEPING
IN MIND THAT ON SATURDAY THE FLOW ALOFT IS UNDER THE INFLUENCE OF
WEAK NWLY FLOW...THE FIRST IMPULSE APPEAR TO SPARK STORMS ACROSS
THE SERN TEXAS PANHANDLE AND EASTERN ZONES...AS THE TRANSPORT OF
GULF MOISTURE INDUCE DEWPOINTS IN THE 50S AND 60S. HENCE PROGGED
PWATS NEARING 1.70 INCHES...A WEAK CAP AND SLIGHT SYNOPTIC LIFT
CAN NOT BE IGNORED. HAVE THEREFORE INTRODUCED POPS ACROSS THE
AFOREMENTIONED AREAS SATURDAY EVENING AND NIGHT. THE SECOND IMPULSE
WILL CREATE THE RETURN OF THE SLOSHING DRYLINE...WHICH IS SHOWN TO
RESIDE ACROSS THE REGION THROUGH MID-WEEK NEXT WEEK...AS FLOW ALOFT
EVOLVES TO SW FLOW DUE TO AN INCOMING PACIFIC UA LOW. THE CAP
APPEARS RELATIVELY STRONG AS THE GFS IS VOID OF PRECIP DESPITE A
LINGERING DRYLINE...VERSUS SIGNALS OF PRECIP ALONG THE DRYLINE EACH
EVENING PER THE ECMWF. WILL MAINTAIN SILENT POPS BEYOND SATURDAY
NIGHT ATTM...AND WILL CONTINUE TO ANALYZE FUTURE MODEL RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 91 57 76 52 83 / 0 20 10 10 10
TULIA 94 59 77 53 83 / 10 20 10 10 10
PLAINVIEW 98 60 78 54 83 / 0 20 10 10 10
LEVELLAND 98 62 81 55 85 / 0 10 10 10 10
LUBBOCK 99 63 81 55 84 / 0 10 10 10 10
DENVER CITY 98 61 83 56 86 / 0 10 10 10 10
BROWNFIELD 99 63 82 56 85 / 0 10 10 10 10
CHILDRESS 97 65 83 57 83 / 30 30 10 10 10
SPUR 102 63 83 57 86 / 0 10 10 10 10
ASPERMONT 102 66 85 57 87 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/29
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
618 PM CDT THU MAY 31 2012
.SHORT TERM...TONIGHT THROUGH SUNDAY
304 PM CDT THU MAY 31 2012
FORECAST CHALLENGES INCLUDE LINGERING SHOWERS INTO THIS
EVENING...THEN CLEARING AND FOG POTENTIAL OVERNIGHT/EARLY FRIDAY
MORNING. ANOTHER CHALLENGE WILL BE THE POTENTIAL FOR REDEVELOPMENT
OF ISOLATED SHOWERS FRIDAY.
CURRENT WATER VAPOR IMAGERY COMBINED WITH 500 MB RAP ANALYSIS SHOW
DEEP MID-LEVEL TROUGH ROTATING SOUTHEAST TROUGH WI/SOUTHERN WI. COLD
AIR ALOFT/LINGERING MID-LEVEL FRONTOGENESIS ASSOCIATED WITH THE
TROUGH WAS PRODUCING SCATTERED SHOWER ACTIVITY ACROSS PORTIONS OF
THE FORECAST AREA. OTHERWISE...CLOUD COVER WAS PRETTY EXTENSIVE
ACROSS THE AREA AND THIS WAS HOLDING TEMPERATURES DOWN IN THE MID/UPPER
50S WHICH IS SOME 20 DEGREES BELOW NORMAL.
31.12Z NCEP MODEL SUITE ALONG WITH THE 31.09Z SREF SHOWING GOOD
AGREEMENT WITH OVERALL SYNOPTIC SETUP THROUGH THE SHORT TERM.
FOR TONIGHT...WILL SEE THAT MID-LEVEL TROUGH MORPH INTO A CLOSED LOW
AND MOVE EAST TOWARD LAKE MICHIGAN THROUGH THE OVERNIGHT HOURS.
APPEARS A FEW DEFORMATION AREA -SHRA WILL LINGER ACROSS THE SOUTH
INTO THE EARLY EVENING HOURS...BUT THEN SHOULD DISSIPATE AROUND 8-9
PM. THE REST OF TONIGHT WILL SEE SLOWLY CLEARING SKIES FROM
NORTHWEST TO SOUTHEAST. CLEARING SKIES/LIGHT WINDS/FAIRLY MOIST
LOWER BOUNDARY LAYER WILL LEAD TO THE POTENTIAL FOR SOME FOG.
MITIGATING FACTOR TO WIDESPREAD FOG WILL BE LIGHT NORTHERLY
COMPONENT TO THE WIND WITH SPEEDS AROUND 10KT AT 500-1000AGL. KEPT
AREAS OF FOG LIMITED TO MISSISSIPPI/WISCONSIN RIVER VALLEYS WHERE
BETTER DECOUPLING OF THE WINDS WILL TAKE PLACE. OTHERWISE...LOOK FOR
OVERNIGHT LOWS ACROSS THE AREA IN THE UPPER 30S IN FAVORED
LOWER-LYING COLD AREAS...TO THE LOWER/MID 40S ELSEWHERE.
ON FRIDAY...THE CLOSED LOW WILL CONTINUE TO DEEPEN AND MOVE SLOWLY
EAST INTO LOWER MICHIGAN. CYCLONIC FLOW/COLD POOL ALOFT WILL RESIDE
OVER OUR AREA WITH STEEP 0-3KM TEMPERATURE LAPSE RATES IN THE
8.5-9C/KM RANGE. NAM ALSO SHOWING 0-3KM MUCAPE AROUND 300J/KG. THIS
SHOULD BE SUFFICIENT FOR EXTENSIVE CUMULUS/TOWERING CUMULUS FIELD
OVER THE FORECAST AREA ALONG WITH ISOLATED SHOWER ACTIVITY. LOOK FOR
HIGHS FRIDAY UNDER THE COLD POOL ALOFT TO TOP OFF IN THE 65-70
DEGREE RANGE. A FEW LINGERING -SHRA STILL POSSIBLE ALONG/NORTHEAST
OF I-94 EARLY FRIDAY EVENING. SCATTERED SHOWERS ALSO POSSIBLE
MAINLY ALONG AND WEST OF THE MISSISSIPPI RIVER FRIDAY NIGHT AS A
WEAK MID-LEVEL TROUGH DROPS SOUTHEAST FROM THE DAKOTAS INTO IA.
FOR SATURDAY...THE CLOSED LOW MOVES INTO EASTERN UPPER MI WITH COLD
CYCLONIC FLOW ALOFT LINGERING ACROSS OUR AREA. THE NAM SHOWS 0-3KM
MUCAPE INCREASING INTO THE 1000-1400J/KG RANGE WHILE 0-1KM ML CAPE
AROUND 500J/KG. THIS WILL LEAD TO ANOTHER DAY OF EXTENSIVE
CUMULUS/TOWERING CUMULUS FIELD ALONG WITH SCATTERED SHRA AND A FEW
THUNDERSTORMS. OTHERWISE...HIGHS SATURDAY ANTICIPATED TO TOP OFF
AGAIN IN THE 65-70 DEGREE RANGE. LOOK FOR THE CONVECTION/CLOUDS TO
DISSIPATED BY EARLY EVENING AS THE LOW/COLD POOL ALOFT MOVES FARTHER
EAST TOWARD LAKE HURON AND RIDGING BUILDS IN FROM THE NORTHERN
PLAINS.
WILL GO DRY ON SUNDAY AS MODELS ARE A BIT SLOWER WITH A MID-LEVEL
TROUGH TOPPING THE RIDGE OVER THE DAKOTAS/CENTRAL PLAINS. WILL
HOWEVER LIKELY SEE AN INCREASE IN MID-HIGH LEVEL CLOUDINESS IN
ADVANCE OF THIS FEATURE.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
304 PM CDT THU MAY 31 2012
31.12Z GFS/ECMWF SHOW A RATHER BLOCKY PATTERN SETTING UP THROUGH THE
PERIOD WITH TROUGHS RESIDING OVER WEST/EAST COASTS AND RIDGE OF HIGH
PRESSURE GETTING PINCHED OVER THE CENTRAL CONUS. SHRA/TS CHANCES
WILL BE SEEN SUNDAY NIGHT THROUGH MONDAY AS A WEAKENING MID-LEVEL
TROUGH TOPS THE RIDGE OVER THE DAKOTAS AND HEADS TOWARD THE UPPER
MISSISSIPPI RIVER VALLEY. FORCING NOT VERY IMPRESSIVE WITH THIS
FEATURE SO WILL CONTINUE WITH SMALLER-END CHANCES FOR NOW. NARROW
RIDGE OF HIGH PRESSURE LOOKS TO KEEP THE AREA DRY THROUGH THE
REMAINDER OF THE PERIOD. TEMPERATURES EXPECTED TO BE MORE SEASONABLE
MONDAY THROUGH THURSDAY AS WELL WITH HIGHS IN THE MID 70S TO AROUND
80.
&&
.AVIATION...TONIGHT AND FRIDAY
618 PM CDT THU MAY 31 2012
VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. CLOUDS CURRENTLY
OVER THE REGION ARE EXPECTED TO SCATTER OUT THIS EVENING. THIS
THEN CREATES THE POSSIBILITY OF SOME FOG IN THE MISSISSIPPI RIVER
VALLEY FOR THE OVERNIGHT HOURS. MOISTURE FROM LAST NIGHTS RAIN HAS
REMAINED TRAPPED UNDER THE CLOUDS AND WITH THE CLEARING SKIES AND
LIGHT WINDS...IT APPEARS TO BE A GOOD NIGHT FOR FOG TO FORM. THE
ONE COMPLICATING FACTOR IS A LIGHT NORTHEAST FLOW IS EXPECTED TO
PERSIST FOR A WHILE THIS EVENING WHICH MAY ADVECT IN SOME DRIER
AIR WITH DEW POINTS IN THE UPPER 30S CURRENTLY ACROSS CENTRAL
WISCONSIN. FOR NOW HAVE CONTINUED WITH THE PREVIOUS FORECAST
TRENDS OF SHOWING PATCHY FOG FOR KLSE AND WILL CLOSELY MONITOR THE
TEMP/DEW POINT TRENDS THROUGH THE EVENING FOR POSSIBLE CHANGES
WITH THE 06Z TAF ISSUANCE. FOG NOT A CONCERN AT KRST WHERE THE
TEMP/DEW POINT SPREAD IS EXPECTED TO REMAIN AT 2-3C THROUGH THE NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
304 PM CDT THU MAY 31 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION...CORRECTED
NWS PUEBLO CO
1036 PM MDT THU MAY 31 2012
.AVIATION...
MAIN AVN CONCERN FOR FRI WILL BE POTENTIAL FOR TS IN THE LATE
AFTERNOON AND EARLY EVE...IN PARTICULAR FROM ABOUT 20Z TO 03Z.
HIGHEST CHANCES WILL BE VC PIKES PEAK AND THE ERN MTN RANGES...SO
HAVE INCLUDED VCTS IN THE KCOS TAF. MUCH LOWER CHANCES AT KPUB
AND KALS...BUT CANNOT ENTIRELY RULE OUT AN ISOLD STORM MOVING AWAY
FROM THE MTS. MORE SIGNIFICANT THREAT IS EXPECTED SAT AFTERNOON
ALONG AND E OF I-25...FOR STORMS WITH STRONG WINDS AND POTENTIAL
FOR LARGE HAIL. ROSE
&&
.PREV DISCUSSION... /ISSUED 338 PM MDT THU MAY 31 2012/
SHORT TERM...
(TONIGHT AND TOMORROW)
CURRENTLY...
AS OF 2 PM...ISOLATED SHOWERS WERE DEVELOPING OVER THE SANGRES AND
SAN JUAN MTNS. OTHERWISE...SKIES WERE MOSTLY CLEAR OVER THE
REMAINDER OF THE REGION. TEMPS OVER THE REGION WERE ON THE COOLER
SIDE...WITH THE SAN LUIS VALLEY AND THE PLAINS IN THE 70-75 RANGE. A
WEAK DIURNAL WIND REGIME WAS DEVELOPING OVER THE AREA.
REST OF AFTERNOON/EVENING...
BEST CHANCE OF ISOLD TSRA ACTIVITY WILL BE OVER THE MTNS...WITH THE
BEST CHANCE OF SOME STRONGER STORMS OVER THE S SANGRES AND RATON
MESA REGION. BOTH LOCAL WRF AND HRRR ARE SHOWING HEAVIER QPF
BREAKING OUT THESE REGIONS DURING THIS TIME PD. ONCE ACTIVITY GETS
GOING...IT SHOULD MOVE IN A SE DIRECTION GIVEN THE NW FLOW ALOFT.
MARGINAL SVR HAIL AND SOME STRONGER GUSTS COULD OCCUR WITH STORMS
GIVEN THE SHEAR IN PLACE.
ONE ISSUE I AM NOT TOO CONFIDENT ABOUT IS SOME CONVECTION MOVING
ACROSS THE FAR E PLAINS THIS EVENING. LATEST HRRR IS HINTING AT THIS
BUT OTHER GUIDANCE KEEPS THE PLAINS ON THE DRY SIDE. FOR NOW WILL
KEEP SILENT POPS OVER THIS REGION AND ALLOW EVENING SHIFT TO ADJUST
POPS IF WARRANTED.
TONIGHT...
DRY CONDITIONS ANTICIPATED DURING THE EARLY MORNING HOURS.
SIMULATIONS DO SHOW A MCS DEVELOPING OVER W NE/SW NE MOVING EAST
LATE TONIGHT...BUT BELIEVE THIS ACTIVITY SHOULD REMAIN OUT OF OUR
CWA AS IT MOVES SE ACROSS W KS.
TOMORROW...
COOL FRONT WILL MOVE ACROSS THE REGION TOMORROW MORNING ASSOCIATED
WITH AFORMENTIONED MCS. WE COULD SEE SOME GUSTY N WINDS...25-30 MPH
IN THE MORNING...OVER THE PLAINS AND POSSIBLY E SXNS OF EL PASO
COUNTY. WINDS WILL QUICKLY TRANSISTION TO AN UPSLOPE COMPONENT...AND
BEST CHANCE OF POPS ONCE AGAIN WILL BE OVER E FACING SLOPES OF E
MTNS. DEPENDING IF THE FRONT STALLS ALONG THE CO/NM BORDER...WE MAY
SEE A BETTER CHANCE OF POPS ALONG THE RATON MESA REGION LATER IN THE
DAY. TEMPS OVERALL SHOULD BE ABOUT 4-8F WARMER THAN TODAY.
LONG TERM...
(FRIDAY NIGHT THROUGH NEXT THURSDAY)
ISOLATED TSRA FRI EVENING SHOULD SHIFT SOUTHEAST INTO THE TEXAS
PANHANDLE OVERNIGHT...AS DEEPER MOISTURE REMAINS JUST SOUTH OF THE
AREA. ON SAT...NICE SOUTHEAST UPSLOPE FLOW DEVELOPS OVER THE
PLAINS...WHICH SHOULD ADVECT A MORE MOIST AND UNSTABLE AIR MASS
INTO THE AREA BY AFTERNOON. MODEL PERFORMANCE THE PAST COUPLE DAYS
SUGGESTS GFS DEWPOINTS APPROACHING 60F ARE SLIGHTLY
OVERDONE...THOUGH EVEN GOING WITH LOWER NAM NUMBERS IN THE 40S TO
50S YIELDS CAPES WELL ABOVE 1000 J/KG ACROSS MUCH OF THE EASTERN
PLAINS EAST OF I-25 BY LATE IN THE DAY. STILL APPEARS WEAK WAVE
WILL WIGGLE EAST THROUGH THE RIDGE AS WELL...ENHANCING UPWARD
MOTION OVER THE AREA INTO SAT EVENING. SOME THREAT OF A SEVERE
STORM OR TWO OVER THE PLAINS NEAR THE KS BORDER...WHERE DEEPER
INSTABILITY AND 0-6KM SHEAR OF 30-40 KNOTS COINCIDE. THUS
CONTINUED TO NUDGE POPS UPWARD SAT AFTERNOON AND EVENING...WITH AT
LEAST A SCATTERED MENTION IN MOST EASTERN MOUNTAIN AND PLAINS
ZONES. SUNDAY STILL LOOKS DRIER AS DEEPER MOISTURE IS PUSHED
EAST...THOUGH LATEST MODELS KEEP SURFACE DEWPOINTS HIGHER THAN
PREVIOUS RUNS...WHICH MAY LEAD TO SLIGHTLY BETTER CONVECTIVE
COVERAGE THAN EARLIER THOUGHT. STILL DON`T SEE MUCH MORE THAN
ISOLATED TSRA OVER MAINLY THE MOUNTAINS...ESPECIALLY AS STEERING
FLOW IS WEAK AS UPPER RIDGE IS OVERHEAD. SHOULD SEE MAX TEMPS STAY
WARM BOTH SAT AND SUN AS 700 MB THERMAL RIDGE REMAINS IN PLACE
ACROSS THE STATE.
UPPER RIDGE AXIS DRIFTS VERY SLOWLY EASTWARD EARLY NEXT WEEK AS
DEEP TROUGH MOVES ONSHORE OVER THE PACIFIC NORTHWEST. BOTH GFS
AND ECMWF ALLOW LOW LEVEL MOISTURE TO CREEP BACK WESTWARD MON IN
THE ABSENCE OF STRONG FLOW ALOFT...WITH BOTH MODELS SUGGESTING AN
UPTURN IN TSRA OVER THE EASTERN HALF OF THE AREA MON
AFTERNOON/EVENING. WEAK UPPER LOW TRAPPED UNDER THE RIDGE MAY ALSO
AID IN UPWARD MOTION...AT LEAST THROUGH MON EVENING. UPPER TROUGH
INCHES CLOSER TO THE REGION TUE/WED...WITH DRYLINE SHARPENING UP
OVER THE EASTERN PLAINS. MAY THUS SEE DAILY ROUNDS OF TSRA ALONG
AND EAST OF THE DRYLINE EACH AFTERNOON TUE-THU...WHILE MOUNTAINS
UNFORTUNATELY STAY MAINLY DRY AND INCREASINGLY BREEZY THROUGH MID-
WEEK. --10
AVIATION...VFR CONDITIONS ANTICIPATED DURING THE NEXT 24H AT
KCOS...KPUB AND KALS. THERE IS A VERY SLIGHT CHANCE OF A PASSING
TSRA AT KCOS LATE THIS AFTERNOON AND EARLY EVENING...AND LATE
TOMORROW AFTERNOON.
A WEAK COOL FRONT WILL CROSS THE KCOS REGION TOWARDS SUNRISE FRIDAY.
BRIEF WIND GUSTS TO 20 MPH MAY OCCUR AFTER FROPA. NO OTHER SENSIBLE
WX IS ANTICIPATED WITH THE FROPA.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
44/50
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1028 PM MDT THU MAY 31 2012
.AVIATION...
MAIN AVN CONCERN FOR FRI WILL BE POTENTIAL FOR TS IN THE LATE
AFTERNOON AND EARLY EVE...IN PARTICULAR FROM ABOUT 20Z TO 03Z.
HIGHEST CHANCES WILL BE VC PIKES PEAK AND THE ERN MTN RANGES...SO
HAVE INCLUDED VCTS IN 3THE KCOS TAF. MUCH LOWER CHANCES AT KPUB
AND KALS...BUT CANNOT ENTIRELY RULE OUT AN ISOLD STORM MOVING AWAY
FROM THE MTS. MORE SIGNIFICANT THREAT IS EXPECTED SAT AFTERNOON
ALONG AND E OF I-25...FOR STORMS WITH STRONG WINDS AND POTENTIAL
FOR LARGE HAIL. ROSE
&&
.PREV DISCUSSION... /ISSUED 338 PM MDT THU MAY 31 2012/
SHORT TERM...
(TONIGHT AND TOMORROW)
CURRENTLY...
AS OF 2 PM...ISOLATED SHOWERS WERE DEVELOPING OVER THE SANGRES AND
SAN JUAN MTNS. OTHERWISE...SKIES WERE MOSTLY CLEAR OVER THE
REMAINDER OF THE REGION. TEMPS OVER THE REGION WERE ON THE COOLER
SIDE...WITH THE SAN LUIS VALLEY AND THE PLAINS IN THE 70-75 RANGE. A
WEAK DIURNAL WIND REGIME WAS DEVELOPING OVER THE AREA.
REST OF AFTERNOON/EVENING...
BEST CHANCE OF ISOLD TSRA ACTIVITY WILL BE OVER THE MTNS...WITH THE
BEST CHANCE OF SOME STRONGER STORMS OVER THE S SANGRES AND RATON
MESA REGION. BOTH LOCAL WRF AND HRRR ARE SHOWING HEAVIER QPF
BREAKING OUT THESE REGIONS DURING THIS TIME PD. ONCE ACTIVITY GETS
GOING...IT SHOULD MOVE IN A SE DIRECTION GIVEN THE NW FLOW ALOFT.
MARGINAL SVR HAIL AND SOME STRONGER GUSTS COULD OCCUR WITH STORMS
GIVEN THE SHEAR IN PLACE.
ONE ISSUE I AM NOT TOO CONFIDENT ABOUT IS SOME CONVECTION MOVING
ACROSS THE FAR E PLAINS THIS EVENING. LATEST HRRR IS HINTING AT THIS
BUT OTHER GUIDANCE KEEPS THE PLAINS ON THE DRY SIDE. FOR NOW WILL
KEEP SILENT POPS OVER THIS REGION AND ALLOW EVENING SHIFT TO ADJUST
POPS IF WARRANTED.
TONIGHT...
DRY CONDITIONS ANTICIPATED DURING THE EARLY MORNING HOURS.
SIMULATIONS DO SHOW A MCS DEVELOPING OVER W NE/SW NE MOVING EAST
LATE TONIGHT...BUT BELIEVE THIS ACTIVITY SHOULD REMAIN OUT OF OUR
CWA AS IT MOVES SE ACROSS W KS.
TOMORROW...
COOL FRONT WILL MOVE ACROSS THE REGION TOMORROW MORNING ASSOCIATED
WITH AFORMENTIONED MCS. WE COULD SEE SOME GUSTY N WINDS...25-30 MPH
IN THE MORNING...OVER THE PLAINS AND POSSIBLY E SXNS OF EL PASO
COUNTY. WINDS WILL QUICKLY TRANSISTION TO AN UPSLOPE COMPONENT...AND
BEST CHANCE OF POPS ONCE AGAIN WILL BE OVER E FACING SLOPES OF E
MTNS. DEPENDING IF THE FRONT STALLS ALONG THE CO/NM BORDER...WE MAY
SEE A BETTER CHANCE OF POPS ALONG THE RATON MESA REGION LATER IN THE
DAY. TEMPS OVERALL SHOULD BE ABOUT 4-8F WARMER THAN TODAY.
LONG TERM...
(FRIDAY NIGHT THROUGH NEXT THURSDAY)
ISOLATED TSRA FRI EVENING SHOULD SHIFT SOUTHEAST INTO THE TEXAS
PANHANDLE OVERNIGHT...AS DEEPER MOISTURE REMAINS JUST SOUTH OF THE
AREA. ON SAT...NICE SOUTHEAST UPSLOPE FLOW DEVELOPS OVER THE
PLAINS...WHICH SHOULD ADVECT A MORE MOIST AND UNSTABLE AIR MASS
INTO THE AREA BY AFTERNOON. MODEL PERFORMANCE THE PAST COUPLE DAYS
SUGGESTS GFS DEWPOINTS APPROACHING 60F ARE SLIGHTLY
OVERDONE...THOUGH EVEN GOING WITH LOWER NAM NUMBERS IN THE 40S TO
50S YIELDS CAPES WELL ABOVE 1000 J/KG ACROSS MUCH OF THE EASTERN
PLAINS EAST OF I-25 BY LATE IN THE DAY. STILL APPEARS WEAK WAVE
WILL WIGGLE EAST THROUGH THE RIDGE AS WELL...ENHANCING UPWARD
MOTION OVER THE AREA INTO SAT EVENING. SOME THREAT OF A SEVERE
STORM OR TWO OVER THE PLAINS NEAR THE KS BORDER...WHERE DEEPER
INSTABILITY AND 0-6KM SHEAR OF 30-40 KNOTS COINCIDE. THUS
CONTINUED TO NUDGE POPS UPWARD SAT AFTERNOON AND EVENING...WITH AT
LEAST A SCATTERED MENTION IN MOST EASTERN MOUNTAIN AND PLAINS
ZONES. SUNDAY STILL LOOKS DRIER AS DEEPER MOISTURE IS PUSHED
EAST...THOUGH LATEST MODELS KEEP SURFACE DEWPOINTS HIGHER THAN
PREVIOUS RUNS...WHICH MAY LEAD TO SLIGHTLY BETTER CONVECTIVE
COVERAGE THAN EARLIER THOUGHT. STILL DON`T SEE MUCH MORE THAN
ISOLATED TSRA OVER MAINLY THE MOUNTAINS...ESPECIALLY AS STEERING
FLOW IS WEAK AS UPPER RIDGE IS OVERHEAD. SHOULD SEE MAX TEMPS STAY
WARM BOTH SAT AND SUN AS 700 MB THERMAL RIDGE REMAINS IN PLACE
ACROSS THE STATE.
UPPER RIDGE AXIS DRIFTS VERY SLOWLY EASTWARD EARLY NEXT WEEK AS
DEEP TROUGH MOVES ONSHORE OVER THE PACIFIC NORTHWEST. BOTH GFS
AND ECMWF ALLOW LOW LEVEL MOISTURE TO CREEP BACK WESTWARD MON IN
THE ABSENCE OF STRONG FLOW ALOFT...WITH BOTH MODELS SUGGESTING AN
UPTURN IN TSRA OVER THE EASTERN HALF OF THE AREA MON
AFTERNOON/EVENING. WEAK UPPER LOW TRAPPED UNDER THE RIDGE MAY ALSO
AID IN UPWARD MOTION...AT LEAST THROUGH MON EVENING. UPPER TROUGH
INCHES CLOSER TO THE REGION TUE/WED...WITH DRYLINE SHARPENING UP
OVER THE EASTERN PLAINS. MAY THUS SEE DAILY ROUNDS OF TSRA ALONG
AND EAST OF THE DRYLINE EACH AFTERNOON TUE-THU...WHILE MOUNTAINS
UNFORTUNATELY STAY MAINLY DRY AND INCREASINGLY BREEZY THROUGH MID-
WEEK. --10
AVIATION...VFR CONDITIONS ANTICIPATED DURING THE NEXT 24H AT
KCOS...KPUB AND KALS. THERE IS A VERY SLIGHT CHANCE OF A PASSING
TSRA AT KCOS LATE THIS AFTERNOON AND EARLY EVENING...AND LATE
TOMORROW AFTERNOON.
A WEAK COOL FRONT WILL CROSS THE KCOS REGION TOWARDS SUNRISE FRIDAY.
BRIEF WIND GUSTS TO 20 MPH MAY OCCUR AFTER FROPA. NO OTHER SENSIBLE
WX IS ANTICIPATED WITH THE FROPA.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
44/50
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
316 AM EDT FRI JUN 1 2012
.DISCUSSION...
...WIDESPREAD CLOUDS WITH HIGH RAIN CHANCES TODAY...
CURRENT...WEAK COOL FRONT EXTENDS SE FROM LOW PRESSURE CENTER OVER
THE OH VLY TO NEAR SABINE PASS. AN AMPLIFIED MID LEVEL SHORT WAVE
TROUGH EXTENDS FROM THE TN VALLEY SWD INTO THE THE CTRL GOMEX WITH
A WEAKER SHORT WAVE RIPPLE NEAR/NORTH OF THE YUCATAN PENINSULA.
INCREASING H25 DIVERGENCE EVIDENT IN RUC H25 ANALYSIS FIELDS AS
DEEPENING SW FLOW ADVECTS HIGH MEAN PWAT AIR OVHD. THIS INCREASE
IN MOISTURE AND LARGE SCALE ASCENT IS KEEPING A CANOPY OF
WIDESPREAD MID/HIGH CLOUDS OVER MOST OF THE PENINSULA.
STATEWIDE RADAR MOSAIC SHOWS NUMEROUS SHOWERS BREAKING OUT JUST
UPSTREAM OF ECFL. ACTIVITY HAS CONGEALED INTO TWO WSW-ENE ORIENTED
BANDS COLOCATED WITH THE BEST FORCED ASCENT. THE FIRST EXTENDED
FROM LAKE COUNTY TO THE NATURE COAST WHILE THE SECOND WAS FROM MIA
TO EVERGLADES CITY. BOTH OF THESE BANDS EXTEND WELL OUT INTO THE
ERN GOMEX.
TODAY/TONIGHT...INCREASING MOISTURE AND LARGE SCALE ASCENT WILL
OVERSPREAD THE PENINSULA TODAY...SETTING THE STAGE FOR A CLOUDY/
WET DAY OVER MOST OF THE PENINSULA. AS IS OFTEN THE CASE WITH SUCH
STRONG SCENT UPSTREAM...THE ACTUAL AREAL QPF IS LOW CONFIDENCE.
WEAKER SHORT WAVE TROUGH NEAR THE YUCATAN EJECTS NEWD THROUGH LATE
MORNING/EARLY AFTERNOON...AHEAD OF THE GOMEX TROUGH WHICH WILL
REACH THE ERN GOMEX THIS AFTERNOON AND SWEEP INTO OR THROUGH ECFL
00Z-06Z...GETTING EAST OF THE STATE BY 12Z. WHILE VERY HIGH PWAT
AIR (2.0"-2.25") OVERSPREADS THE CWA BY 18Z MID/UPPER ASCENT KEEPS
WIDESPREAD MID-HIGH CLOUD COVER IN PLACE...WHICH LIMITS SURFACE
HEATING/INSTABILITY TO SOME DEGREE. EXPECT MAX TEMPS ONLY IN THE
M80S...WITH U80S CONFINED TO AREAS WHICH SEE PEEKS OF SUN ALTHOUGH
CLOUDS/PRECIP WILL LIKELY FILL IN QUICKLY IN THESE SPOTS. HAVE
FINALLY ACQUIESCED TO MAV MOS GUIDANCE - 80/90 POPS OVER MOST OF
THE CWA...AND NEAR 100 FOR THE COUNTIES AROUND LAKE OKEE.
00Z 24-HOUR QPF (7 AM FRI-7 AM SAT) RANGED FROM AROUND 0.50" NORTH
TO 1.50" OR SO SOUTH. THE NEW 06Z PROGS ARE EVEN LOWER...GENERALLY
IN THE 0.25 TO 0.75 RANGE OVER ALL BUT MARTIN COUNTY (1.0"-1.25").
COORD WITH ADJACENT OFFICES ON HEAVY RAIN THREAT AND AGREE THAT
GIVEN THE CLOUD COVER/INSTABILITY ISSUES...A FLOOD WATCH IS NOT
NEEDED FOR OUR SOUTHERN COUNTIES ATTM. HOWEVER...LOCALIZED HEAVY
RAIN/URBAN TYPE FLOODING WILL BE A CONCERN...AND WILL ADDRESS AS
SUCH IN THE HWO/G-HWO SUITE.
EXPECT PRECIP (SHOWERS/ISOLATED STORMS) TO CONTINUE REDEVELOPING
WELL AFTER SUNSET GIVEN CONTINUED ASCENT ASSOCIATED WITH APPROACH
OF H50 TROUGH AXIS OVERHEAD...FINALLY TAPERING OFF LATE TONIGHT
AS THE MID LEVEL TROUGH AND ATTENDANT WEAK SURFACE BOUNDARY SLIDE
EAST INTO THE ATLANTIC.
SAT-SUN... LOOKS TO BE A WARM AND DRY COUPLE OF DAYS AS THE DEEP
LAYER MOISTURE WILL HAVE SHIFTED EAST AND SOUTH OF THE AREA AND
THE WEST TO NORTHWEST UPPER FLOW ADVECTS A DRIER AIR MASS INTO
CENTRAL FLORIDA. AFTERNOON HIGHS IN THE LOWER 90S INTERIOR AND THE
UPPER 80S TO LOWER 90S...DEPENDING ON HOW EARLY THE SEA BREEZE
FORMS AND PUSHES THROUGH...AT THE COAST.
MON-THU...WEAK HIGH PRESSURE WITH THE SURFACE AND LOW LEVEL RIDGE
AXIS TO THE SOUTH OF CENTRAL FLORIDA AND TROUGHING OVER THE
SOUTHEAST RESULTS IN AN EXTENDED PERIOD OF WESTERLY FLOW. WEST TO
SOUTHWEST WINDS USUALLY MEAN A WARM DAY AND NO EXCEPTION THIS TIME
PERIOD. HIGHS MONDAY IN THE LOW TO MID 90S INTERIOR AND LOW 90S THE
RULE ALONG THE COAST. THE DEEP WEST TO SOUTHWEST FLOW WILL ALSO
LIMIT THE INLAND PUSH OF ANY SEA BREEZES. THERE SHOULD BE ENOUGH
MOISTURE TO PRODUCE LATE AFTERNOON EVENING STORMS EACH DAY.
&&
.AVIATION...WIDESPREAD MULTILAYERED CLOUDS PRECIP WILL OVERSPREAD
THE TERMINALS THROUGHOUT THE MORNING AND AFTERNOON. PREVAILING
OVC-BKN VFR CIGS WITH OCNL MVFR CIGS AND MVFR/IFR VSBYS IN CLOUDS
AND PRECIP THROUGH 06Z...TAPERING OFF THEREAFTER.
&&
.MARINE...LOCAL BUOY DATA SHOWS SEAS CONTINUING TO RUN ABOUT 2-3FT
FOR THE MOST PART. EXPECT THIS TREND TO CONTINUE TODAY/TONIGHT IN
OFFSHORE 10-15KT FLOW REGIME. MAIN CONCERN WILL BE LOCALLY HIGHER
WINDS/SEAS IN NUMEROUS SHOWERS/STORMS.
SAT-TUE...SURFACE RIDGE SUPPRESSED TO THE SOUTH RESULTS IN A WEAK
OFFSHORE FLOW. LIMITED WINDS TO 20 KNOTS OVERNIGHT TUE/THUR MORNING
AS IT APPEARS THERE WAS FEEDBACK ISSUES WITH THE OFFSHORE WINDS WED
TIME FRAME THEREFORE FOR THIS CYCLE LIMITED THE OFFSHORE WINDS
SEBASTIAN NORTH TO 20 KNOTS. WEST TO SOUTHWEST STEERING WINDS WILL
TEND TO PUSH ANY STORMS THAT DEVELOP ON THE MAINLAND BACK TO THE
COAST AND NEARSHORE WATERS. SEAS 2 TO 4 FEET OFFSHORE AND 1 TO 3
FEET NEARSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 85 71 89 67 / 80 30 20 10
MCO 84 70 91 69 / 80 40 20 10
MLB 84 72 90 69 / 90 50 30 10
VRB 84 72 90 69 / 90 50 30 10
LEE 85 71 91 69 / 80 30 20 10
SFB 85 71 93 69 / 80 40 20 10
ORL 84 72 93 72 / 80 40 20 10
FPR 84 73 90 69 / 100 50 30 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT GRAPHICS....WIMMER
AREA FORECAST DISCUSSION
NWS MIAMI FL
202 AM EDT FRI JUN 1 2012
.AVIATION...
SOUTHERLY FLOW AND MOISTURE TRANSPORT FROM WESTERN CUBA TOWARD KEY
WEST IN ADDITION TO A WEAK SFC BOUNDARY AND 50 KNOT SUBTROPICAL
JET IS LEADING TO A LINE OF THUNDERSTORMS OVER MAINLAND MONROE AND
THE ADJACENT GULF WATERS. THIS ACTIVITY IS EXPECTED TO PUSH
NORTHWARDS TOWARD KAPF OVER THE NEXT SEVERAL HOURS...WITH
PREVAILING MVFR CONDITIONS EXPECTED. RAIN SHOULD CLEAR OUT ACROSS
THE SOUTHEAST TAF SITES INCLUDING MIA...TMB...OPF NORTHWARD
TOWARDS KFLL OVER THE NEXT SEVERAL HOURS AS THIS ACTIVITY LIFTS
NORTHWARD. HOWEVER...LEFT VCSH IN THE TAFS IN CASE A FEW SHOWERS
DECIDE TO DEVELOP. MVFR CIGS HAVE DEVELOPED ACROSS THE SOUTHEAST
TAF SITES...AND IT IS POSSIBLE THIS COULD PREVAIL THROUGH THE
OVERNIGHT HOURS. AS A SHORTWAVE TROUGH OVER THE CENTRAL GULF MOVES
TOWARDS THE FLORIDA PENINSULA THIS AFTERNOON...HEAVY RAINFALL WITH
EMBEDDED THUNDERSTORMS ARE POSSIBLE. GUIDANCE HAS PREVAILING IFR VIS
AND MVFR CIGS FOR 4-8 HOURS ACROSS ALL TAF SITES. ATTM...KEPT
PREVAILING MVFR CIGS AND VIS...BUT IFR AND EVEN LIFR CONDITIONS
ARE POSSIBLE IN HEAVY RAIN AND/OR THUNDERSTORMS. MODEL GUIDANCE
DIFFERS ON HOW QUICKLY THE TROUGH WILL MOVE THROUGH FLORIDA AND
HOW QUICKLY THE DEEPER MOISTURE WILL GET PUSHED TO THE SOUTH AND
EAST. SO IT IS POSSIBLE THAT THE PREVAILING MVFR VIS/CIG COULD
CONTINUE THROUGH THE END OF THE TAF PERIOD...ESPECIALLY FOR THE
SOUTHEAST TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 953 PM EDT THU MAY 31 2012/
UPDATE...NO CHANGES ARE PLANNED FOR THE EVENING UPDATES. A STEADY
STREAM OF RICH TROPICAL MOISTURE CONTINUES TO TRANSLATE NORTHWARD
FROM THE CARIBBEAN IN THE INCREASING SOUTHWEST FLOW ALOFT AHEAD OF
A DEEPENING MID LEVEL TROUGH OVER THE SOUTHEAST STATES. THIS ALSO
EVIDENT ON WATER VAPOR IMAGERY AND THE 00Z MFL SOUNDING. ALSO
EVIDENT ON WATER VAPOR IS A VORT MAX MOVING INTO THE SOUTHEAST GULF
AND THIS WILL ONLY ENHANCE CONVECTIVE ACTIVITY LATER TONIGHT INTO
EARLY FRIDAY. THE HRRR ALSO INDICATES CONVECTION TO CONTINUE
THROUGH THE NIGHT WITH A RAPID INCREASE AS THE TROUGH APPROACHES
ALONG THE SOUTHWEST COAST AFT 09Z.
KOB
PREV DISCUSSION... /ISSUED 639 PM EDT THU MAY 31 2012/
AVIATION...A VRY MOIST SW WND FLOW ALOFT WITH AN IMPULSE OF
INSTABILITY MOVG NE FM THE W CUBA/YUCATAN CHANNEL AREA WL LEAD
TO CLDY SKIES AND INCRG CHC OF RA/ISOLD TSRA MOVG ONTO THE W COAST
BUT MOST LIKELY NOT MAKING TO THE E COAST THRU 06Z. VFR XPCTD ALL
TERMINALS THRU 06Z XCPT PSBL MVFR CIG/VSBY AT KAPF BUT NOT DVLPG
E COAST TIL 12Z. AFT 12Z NMRS/WDSPRD RA WITH ISOLD TSRA PSBL WITH
WDSPRD MVFR CIG/VSBY PSBL. SFC WND DCRG TO LESS THAN 10 KTS BUT ON
E COAST SSE MOSTLY BUT LGT SSW FLOW PSBL 06Z TO 12Z WITH WNDS BCMG
SSE AND 10 TO 15 KTS. AT KAPF SW WND LESS THAN 10 KTS THRU 09Z
THEN BCMG SE-SSE WITH W COAST SEA BRZE AFT 16Z.
PREV DISCUSSION... /ISSUED 244 PM EDT THU MAY 31 2012/
SHORT TERM (TONIGHT-SATURDAY NIGHT)...
THE LATEST WATER VAPOR LOOP SHOWED BROAD CYCLONIC FLOW ACROSS THE
EASTERN HALF OF THE COUNTRY EXTENDING SOUTH ACROSS THE GULF OF
MEXICO WITH A FEW NOTABLE SHORTWAVE TROUGHS EMBEDDED AND PLENTY OF
MID/UPPER MOISTURE SPREADING NORTH OVER THE FLORIDA PENINSULA FROM
THE CARIBBEAN. THE LATEST MODEL GUIDANCE HAS INITIALIZED WELL WITH
THIS UPPER PATTERN AND SHOWS THE SHORTWAVE TROUGH CURRENTLY OVER OR
NEAR THE YUCATAN PENINSULA LIFTING NORTHEAST TONIGHT THEN ACROSS THE
LOCAL AREA FRIDAY AND FRIDAY NIGHT WITH DRY AIR GRADUALLY FILLING IN
THROUGH THE SATURDAY NIGHT. PLENTY OF DEEP LAYER MOISTURE LIFTING
NORTHEAST OUT OF THE CARIBBEAN ASSOCIATED WITH THIS UPPER FEATURE
WILL KEEP THE RAINFALL CHANCES ELEVATED ACROSS THE LOCAL AREA
THROUGH THIS TIME. THE LATEST MODEL PWAT VALUES REFLECT THIS AND
INCREASE INTO THE 2-2.5 INCH RANGE THROUGH THE DAY FRIDAY AS THIS
SURGE MOISTURE SPREADS NORTHEAST OVER THE AREA. A BLEND OF THE RAW
MODEL QPF AND GUIDANCE INDICATES ADDITIONAL RAINFALL
ACCUMULATIONS REACHING THE 2 TO 4 INCH RANGE ACROSS THE BULK OF THE
AREA THROUGH THIS TIME. THE LATEST HPC GUIDANCE ALSO INDICATES THESE
TOTALS AND KEEPS THE HIGHER END OF THIS RANGE OVER THE SOUTHERN HALF
OF THE LOCAL AREA OR SOUTH OF ALLIGATOR ALLEY. AS TYPICALLY OBSERVED
DURING THESE EVENTS...LOCALLY HIGHER AMOUNTS WILL CERTAINLY BECOME A
POSSIBILITY WHERE THE HEAVIER ACTIVITY BECOMES CONCENTRATED.
CONSIDERING THE RECENT RAINFALL ACTIVITY OVER THE PAST WEEK OR
TWO...INTERESTS ARE ENCOURAGED TO MONITOR LATER FORECASTS FOR
UPDATES THROUGH THIS TIME AS A FLOOD WATCH IS NOT OUT OF QUESTION.
SATURDAY AND SATURDAY NIGHT...DESPITE SOME MINOR TIMING DIFFERENCES
BETWEEN THE LATEST MODEL GUIDANCE...A GENERAL DRYING PATTERN WILL BE
ANTICIPATED AS THE UPPER TROUGH MOVES THROUGH FROM WEST TO EAST.
THIS DRY AIR COMBINED WITH SUBSIDENCE ON THE BACK SIDE OF THE TROUGH
SHOULD LEAD TO CLEARING CONDITIONS COME SATURDAY NIGHT.
HOWEVER...THE NAM IS QUITE A BIT SLOWER WITH THIS DRIER AIR
SPREADING EAST ACROSS THE AREA. CONSIDERING THE UNCERTAINTIES AT
THIS TIME...WE WILL NOT COMPLETELY RULE OUT THE POTENTIAL FOR
ADDITIONAL RAINFALL THROUGH THIS TIME AND CONTINUE TO MONITOR THE
EVOLUTION OF THIS SYSTEM.
LONG TERM (SUNDAY-WEDNESDAY)...
DRIER CONDITIONS WILL BE EXPECTED THROUGH THE BEGINNING OF THE
UPCOMING WEEK. HOWEVER...AFTERNOON SHOWERS/TSTMS WILL BE ANTICIPATED
EACH DAY. WITH THE MID/UPPER FLOW CONTINUING OUT OF THE WEST THE
BEST RAINFALL CHANCES SHOULD REMAIN OVER THE EASTERN AREAS.
MARINE...
LIGHT SOUTHERLY WINDS ARE EXPECTED EACH DAY THROUGH
FRIDAY...THEN INCREASING INTO THE MODERATE RANGE INTO SATURDAY
AS A FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST. SCATTERED TO
NUMEROUS SHOWERS WITH ISOLATED THUNDERSTORMS WILL CONTINUE INTO
SATURDAY...WHICH COULD LEAD TO PERIODS WITH GUSTY WINDS AND CHOPPIER
CONDITIONS IN AND AROUND ANY HEAVY SHOWER OR STORM THAT DEVELOPS.
DRIER CONDITIONS WITH LIGHT WEST NORTHWEST WINDS WILL BE EXPECTED IN
THE WAKE OF THIS SYSTEM SUNDAY INTO THE UPCOMING WEEK.
AVIATION...
SKIES WERE STARING TO CLEAR EARLY THIS AFTERNOON OVER
SOUTH FLORIDA. THIS WILL ALLOW FOR A SEA BREEZE TO SET UP OVER THE
EAST COAST METRO AREAS AND PUSH SLOWLY INLAND. SO WILL SHOW VRB 05
KTS UNTIL ABOUT 20Z THEN A 160 TO 170 DEGREE DIRECTION WITH SPEEDS
OF 5 TO 10 KNOTS. THE EAST COAST SEA BREEZE WILL ALSO ALLOW FOR
THUNDERSTORMS TO DEVELOP OVER THE INTERIOR AREAS AND PUSH BACK
TOWARD THE EAST COAST TAF SITES LATE THIS AFTERNOON. SO WILL PUT IN
A VCTS IN FOR THE EAST COAST TAF SITES FROM 20Z UNTIL 01Z.
TROPICAL MOISTURE WILL CONTINUE OVER SOUTH FLORIDA TONIGHT ALLOWING
FOR SCATTERED SHOWERS TO CONTINUE TONIGHT AT ALL OF THE TAF SITES.
SO WILL CONTINUE THE VCSH FOR ALL OF SOUTH FLORIDA TAF SITES FOR
TONIGHT.
THE CEILING AND VIS WILL ALSO REMAIN IN THE VFR CONDITIONS FOR ALL
OF SOUTH FLORIDA TAF SITES THIS AFTERNOON INTO TONIGHT...DUE TO THE
UNKNOWN TIMING OF THE SHOWER AND THUNDERSTORM ACTIVITY AFFECTING THE
TAF SITES.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 71 89 75 / 70 60 40 20
FORT LAUDERDALE 85 75 89 78 / 70 60 40 30
MIAMI 87 75 90 77 / 70 60 40 30
NAPLES 83 72 88 73 / 80 60 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...14/MJB
AVIATION/RADAR...84/AK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
355 AM EDT FRI JUN 1 2012
.SHORT TERM... /TODAY THROUGH SATURDAY NIGHT/
SFC LOW CONTINUES TO DEEPEN ACROSS SOUTHERN INDIANA EARLY THIS
MORNING IN RESPONSE TO STG TROUGH DIGGING THROUGH IOWA. BEST
ISENTROPIC LIFT HAS SHIFTED N INTO MICHIGAN...TAKING STEADIER PRECIP
WITH IT. MID LEVEL DRY SLOT HAS MADE IT INTO MUCH OF THE
AREA...KEEPING PRECIP MORE SCT IN NATURE. MOST LOCATIONS MISSED OUT
ON BEST RAINFALL...RECEIVING LESS THAN ONE QUARTER INCH. THE
EXCEPTION WAS NW OF KSBN TO THE LAKE WHERE BIT OF DEFORMATION ZONE
SETUP TO ALLOW FOR THREE QUARTERS TO OVER AN INCH OF RAIN FALL.
ADDITIONAL RAINFALL ACROSS THE NW WILL LIKELY BE UNDER A TENTH OF AN
INCH AS MAIN FOCUS FOR PRECIP SHIFTS SE TO HOPEFULLY GIVE PORTIONS
OF NW OHIO SOME MORE RAINFALL WITH LIMA OH ONLY SEEING A HUNDREDTH
OF AN INCH SO FAR. HRRR HAS HAD A DECENT HANDLE ON TRENDS WITH
ACTIVITY SLOWLY WINDING DOWN ACROSS NW 2/3RDS AND UPSWING IN PRECIP
AS SFC LOW MOVES INTO OHIO WITH BAND OF SHOWERS WORKING NW SOMEWHAT.
LAST HALF HOUR OR SO OF RADAR TRENDS SUGGEST THIS MAY BE UNDERWAY.
KEEPING FORECAST SIMPLE HAVE ONLY WENT WITH CHC SHOWER WORDING IN
ALL AREAS EXCEPT EAST QUARTER OR SO WHERE PRECIP LIKELY TO AFFECT
FOR AT LEAST THIS MORNING. EXTENSIVE CLOUD COVER WILL LIKELY KEEP
TEMPS PRETTY STEADY THIS MORNING AND POSSIBLE EVEN FALLING SOME AS
COLDER AIR WRAPS AROUND THE LOW AND WINDS INCREASE AS A RESULT OF
TIGHTENING PRESSURE GRADIENT ACROSS THE GREAT LAKES.
SPOKE OF ENERGY AND NW FLOW OFF THE LAKE WILL ALLOW FOR CLOUDS TO
CONTINUE ACROSS THE AREA THIS AFTERNOON WITH A FEW SHOWERS STILL
POSSIBLE ACROSS THE NORTH. BACKED OFF HIGHS A FEW DEGREES ESPECIALLY
NORTH WITH LITTLE OVERALL DIURNAL SWING EXPECTED.
OTHER THAN A FEW LIGHT SHOWERS OR LINGERING SPRINKLES...DRY
CONDITIONS SHOULD OVERSPREAD THE REGION WITH DECREASING CLOUDS.
UPPER LOW WILL MOVE NORTH OUT OF THE REGION SATURDAY. PIECE OF
ENERGY WILL MOVE THROUGH THE FLOW AND TRACK ACROSS LOWER GREAT LAKES
INTO THE OHIO VALLEY. FEATURE WILL BE MSTR STARVED BUT MAY BE
SUFFICIENT TO SPARK OFF A FEW LIGHT SHOWERS. WILL MAINTAIN CHC POPS
SATURDAY. TEMPS WILL WARM A GOOD 10 TO 15 DEGREES OR MORE ACROSS
MOST OF THE REGION DESPITE MOSTLY CLOUDY SKIES. LOWS SAT NGT WILL
DROP BACK INTO THE LOWER 50S UNDER CLEARING SKIES.
&&
.LONG TERM...
HIGH LAT BLOCK OVR THE NORTH ATL SPURNING STG NEG NAO WHICH WILL
CONT TO PERSIST THROUGH THIS PD RESULTING IN ANOMALOUS NRLY FLW ACRS
MUCH OF THE ERN US AND WHICH WILL PUSH ACTIVE POLAR JET SOUTH ACRS
THE GULF COAST. THUS XPC DRY AND SEASONABLY COOL WX TO PERSIST
THROUGH THE PD. OP GFS SOLUTION CONTS TO LOOK LIKE AN OUTLIER
SOLUTION SUN NIGHT/MON W/CONV FEEDBACK NOTED ALOFT. ALL OTHER MED
RANGE SOLUTIONS AT THAT RANGE ARE DRY YET AM FORCED TO HOLD ONTO 20S
FOR COLLABORATION.
&&
.AVIATION...
EXPECTING A SLOW DECREASE IN RAINFALL ACROSS THE AREA OVER THE
NEXT SEVERAL HOURS AS MID LEVEL DRY SLOT WINS OUT OVER INCREASING
LIFT ACROSS THE AREA. SHOWERS WILL STILL IMPACT KSBN NEXT COUPLE
OF HOURS WITH A LULL IN PRECIP AT KFWA. UPSTREAM TRENDS SUGGESTS
VARIABLE CIGS THROUGH THE NIGHT RANGING FROM AS LOW AS 700 FT TO
AT TIMES APPROACHING VFR. MODELS STILL SUGGEST ANOTHER ROUND OF
HEAVIER SHOWERS MOVING INTO KFWA TOWARDS 12Z. HOWEVER...LESS THAN
OPTIMISTIC SO HAVE BACKED OFF ON VSBY AND WENT TO SHOWER MENTION
VS RAIN.
WINDS HAVE BEEN GUSTY AT TIME AND WILL INCREASE INTO FRIDAY AS SFC
LOW CONTINUES TO DEEPEN AND TRACK ACROSS THE EASTERN GREAT LAKES
FRIDAY NIGHT. STRONG SUBSIDENCE SHOULD BRING CLEARING SKIES INTO
BOTH SITES...WITH KFWA THE FIRST AS LOCATIONS CLOSER TO THE LAKE
WILL SEE SOME WRAP AROUND CLOUDS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...RIP CURRENT RISK THROUGH LATE TONIGHT FOR INZ003.
MI...RIP CURRENT RISK THROUGH LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR LMZ043-046.
&&
$$
SHORT TERM...FISHER
LONG TERM...T
AVIATION...FISHER
AREA FORECAST DISCUSSION
NWS WICHITA KS
326 AM CDT FRI JUN 1 2012
.DISCUSSION...
THE MAIN FORECAST CHALLENGES ARE THE MULTIPLE CHANCES FOR
PRECIPITATION THROUGH THE FORECAST.
SYNOPSIS:
THE MAIN UPPER LEVEL DISTURBANCE ACROSS THE CONUS IS MOVING EAST
OVER THE GREAT LAKES THIS MORNING LEAVING THE CENTRAL PLAINS UNDER
NORTHWEST FLOW. RIPPLES IN THE NORTHWEST FLOW HAVE HELPED TO
DEVELOP SCATTERED LIGHT SHOWERS ACROSS WESTERN KANSAS WHICH WILL
EVENTUALLY BE THE MAIN CONCERN FOR WEATHER TODAY. DESPITE THESE
LIGHT SHOWERS OVER WESTERN KANSAS...EASTERN KANSAS IS UNDER MOSTLY
CLEAR SKIES THIS MORNING WITH SURFACE HIGH PRESSURE MOVING
OVERHEAD. WINDS ARE LIGHT AND VARIABLE AND TEMPERATURES ARE IN THE
40S ACROSS THE AREA.
TODAY - SUNDAY:
A RIPPLE IN THE NORTHWESTERLY FLOW IS AND WILL CONTINUE TO BE THE
FOCUS FOR PRECIPITATION DEVELOPMENT TODAY. THE NAM/GFS/HRRR ALL
CONTINUE TO SHOW SHOWER AND THUNDERSTORM DEVELOPMENT THROUGHOUT THE
DAY TODAY. THE HRRR SEEMS TO HAVE A DECENT HANDLE OF CURRENT
TRENDS...AND THAT GIVES CONFIDENCE TO ITS SOLUTION...DEVELOPING
PRECIPITATION ACROSS CENTRAL KANSAS LATER THIS MORNING. THESE
SHOWERS AND THUNDERSTORMS WILL MOVE EASTWARD ACROSS THE STATE TODAY.
THE OVERCAST SKIES AND RAIN WILL HELP KEEP TEMPERATURES DOWN AND
HAVE DECREASED HIGH TEMPS SLIGHTLY TO ACCOUNT FOR THIS. TEMPS WILL
BE ABOUT 10-15 DEGREES BELOW NORMAL FOR EARLY JUNE.
SATURDAY SHOULD REMAIN DRY AND WARMER IN THE WAKE OF THE SYSTEM
TODAY...BUT PRECIPITATION CHANCES WILL RETURN EARLY SUNDAY MORNING
AS A DISTURBANCE UNDERCUTS THE UPPER LEVEL RIDGE AND APPROACHES THE
STATE. HAVE KEPT PRECIPITATION CHANCES THROUGH SUNDAY AND KNOCKED
MAX TEMPS DOWN SLIGHTLY WITH THE CLOUD COVER AND RAIN CHANCES.
MONDAY - THURSDAY:
UPPER LEVEL RIDGING WILL BUILD IN FOR THE FIRST WEEK IN JUNE. THE
MEDIUM RANGE GUIDANCE IS SOMEWHAT SIMILAR WITH THE EXTENDED
FORECAST...BUT THEY ARE CURRENTLY SHOWING SMALL DISTURBANCES
UNDERCUTTING THE RIDGE AND BRINGING CHANCES FOR PRECIP. WITH THE
NORTHWEST FLOW AND THESE DISTURBANCES CANNOT RULE OUT THE CHANCES
FOR PRECIPITATION...BUT CONFIDENCE ON TIMING AND COVERAGE IS LOW.
HAVE MAINTAINED MODEL CONSENSUS THROUGH THE EXTENDED FOR NOW. THE
BEST CHANCE FOR WIDESPREAD PRECIP DOES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY...BUT WILL NEED TO WATCH THIS AS THE FORECAST
EVOLVES. TEMPERATURES WILL GENERALLY WARM INTO THE UPPER 80S AND
LOW 90S THROUGH THE EXTENDED FORECAST.
BILLINGS
&&
.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
NO CHANGES FROM PREVIOUS THINKING. RIPPLE IN NORTHWEST FLOW ALOFT
WILL RESULT IN WARM AIR ADVECTION/ISENTROPIC AROUND 700MB LATER
TONIGHT AND DURING THE DAY ON FRI. SHOULD SEE ALTOCUMULUS DECK
DEVELOP AND MOVE ACROSS ALL SITES STARTING IN THE PREDAWN HOURS AT
KRSL AND REACHING KCNU BY MIDDAY FRI. GIVEN FORECAST LIFT...SHOULD
SEE SOME HIGH BASED RAIN SHOWERS DEVELOP...BUT CONFIDENCE IN
TIMING/COVERAGE AND MARGINAL INSTABILITY WOULD ONLY JUSTIFY VCSH.
CLEARING ANTICIPATED AROUND SUNSET WITH BOTH LOSS OF HEATING AND
EXIT OF SHORTWAVE. -HOWERTON
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 67 54 83 65 / 40 20 10 20
HUTCHINSON 67 53 83 64 / 40 10 10 20
NEWTON 65 52 82 64 / 40 10 10 20
ELDORADO 65 52 81 63 / 40 20 10 20
WINFIELD-KWLD 68 55 82 65 / 40 30 10 30
RUSSELL 69 53 83 64 / 40 10 10 20
GREAT BEND 70 53 84 63 / 40 10 10 20
SALINA 66 51 83 63 / 40 10 0 20
MCPHERSON 66 52 83 64 / 40 10 10 20
COFFEYVILLE 69 53 81 63 / 30 20 10 20
CHANUTE 67 52 81 62 / 30 10 10 10
IOLA 67 51 81 62 / 20 10 0 10
PARSONS-KPPF 68 52 81 63 / 30 20 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1251 AM EDT FRI JUN 01 2012
.Forecast Update...
Issued at 1015 PM EDT Thur May 31 2012
The storms this evening have weakened significantly over the last
couple of hours. We have therefore allowed the Severe Thunderstorm
Watch to expire. A few strong thunderstorms remain in south central
Kentucky this evening. Gusty winds and small hail may be seen with
these storms over the next few hours. For the rest of the night, a
second area of showers and thunderstorms has developed back to the
west. The RAP shows at least scattered precip continuing through the
night as the surface low continues to move northeast across the
forecast area. Soundings show instability diminishing overnight as
well. Will therefore hold on to only scattered to isolated thunder
after 06Z. Updates are already out.
.Short Term (Tonight through Friday night)...
Issued at 320 PM EDT Thu May 31 2012
A 500mb trough now over the Upper Midwest will amplify rapidly by
Friday morning as jet stream energy digs south along its back side.
Weak low pressure currently (@ 2pm EDT) over southern Illinois will
slowly move east across southern Indiana and is expected to begin to
deepen pretty rapidly just as it passes north of Louisville late
this evening. An unusually chilly early June airmass will then
arrive early Friday, keeping afternoon highs in the lower to mid
60s, which is not too far from the all time record low high for June
1st (62 at Standiford).
This evening`s precipitation will mostly likely begin as a north
south orientated line of convection that is already beginning to
develop across southern Illinois. Moisture return up to this point
has not been robust as southeast winds have kept dewpoints in the
mid 50s. Winds will eventually veer to the south or southwest by
late afternoon as the aforementioned surface low moves closer to
Louisville.
Despite only weak to moderate instability and moisture return,
strong upper air dynamics coupled with wide surface T/Td depressions
may lead to the formation of one or more bowing segments with a
threat of damaging winds. With backed surface winds, an isolated
tornado east of the developing surface low is possible. However, the
large T/Td depression and relative high Lifted Condensation Level
(LCL) would argue against tornado formation.
Best guess on the timing for this line would have it arriving over
our western counties by late afternoon, crossing Interstate 65 by
early to mid evening, and exiting our Bluegrass Counties around
midnight. With the arrival of this strengthening upper trough,
expect that occasional showers may continue through the early
morning hours.
Even with showers ending during the morning hours, expect somewhat
of a dingy day Friday with persistent low clouds and somewhat brisk
west winds around 10 to 15 mph continue through the afternoon. Skies
will tend to slowly clear beginning from our southwest counties by
late afternoon, with partly cloudy skies arriving over our entire
CWA after midnight. Temperatures will cool well into the 50 to 55
degree range.
.Long Term (Saturday through Wednesday night)...
Issued at 320 PM EDT Thu May 31 2012
Saturday through Sunday night...
The exiting low pressure system to the north and east will place the
forecast area under northwest flow, leaving temperatures cooler than
normal for this time of year. Additionally, this type of flow is
notorious for placing central Kentucky and southern Indiana under
persistent cloud cover and occasional showers. Therefore, have
mentionable PoPs on Saturday afternoon and despite instability
looking weak, given the time of year, included isolated t-storms due
to daytime heating possibly kicking things up a notch. Shower
chances may spread further south Saturday night but looks to clear
out until early next week.
As previously alluded to, temperatures will be below average on
Saturday and Saturday night, with highs in the mid 70s and lows in
the mid 50s. Sunday will see some warm up closer to normal with
highs in the upper 70s and lower 80s and lows in the upper 50s to
low 60s.
Monday through Wednesday night...
This time frame is proving to be a little on the tricky side for the
beginning of the week as the GFS has a surface low pressure system
crossing through the Ohio Valley Monday afternoon into the overnight
period, bringing decent precip chances to the forecast area.
However, the ECMWF is keeping the area dry through the end of the
forecast period. What they do agree on is the stout ridge that
builds over the Plains, leaving the Ohio Valley on the periphery.
Given the uncertainty, have left some PoPs in for Monday afternoon
but will certainly need to be monitored for model changes over the
next day or two. Any precipitation that does fire up will be in the
form of thunderstorms. It should be dry otherwise through Wednesday.
Temperatures look to linger near normal, reaching the mid 80s during
the days and the low 60s overnight.
&&
.Aviation (06Z TAF Issuance)...
Updated at 1250 AM EDT Fri Jun 1 2012
Low pressure is centered over southeast Indiana at this time, with
an attendant cold front still west of the TAF sites, but not for
long. In the near term, still have some storms over LEX, but the
instability for thunder will leave soon, and should just have to
deal with some light to moderate rains as well as lower cigs. Obs on
the west side of the surface low indicate IFR or worse cigs. Have
gone more pessimistic with updates early this morning, showing poor
flying conditions overnight. It will take some time for these low
clouds to get scoured out. Have IFR conditions till mid morning when
bases should lift to MVFR levels. Expect MVFR clouds to remain
through the day as models are not showing us getting rid of these
clouds till late in this TAF period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........EER
Short Term.......JSD
Long Term........LG
Aviation.........RJS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1148 PM CDT THU MAY 31 2012
.UPDATE...
ISSUED AT 1142 PM CDT THU MAY 31 2012
MAIN ADJUSTMENTS WITH THE EVENING GRIDDED FORECAST UPDATES WAS TO
FIRST HANDLE THE TIMING ON THE EXIT OF THE PRECIPITATION...AND
SECONDLY TO DEAL WITH LOW CLOUDS...WINDS/WIND
GUSTS...TEMPERATURE/DEWPOINT CHANGES AND ANY WRAP AROUND
PRECIPITATION.
THE 12KM NAM/13KM RUC/3KM HRRR APPEARED TO HAVE A GOOD HANDLE ON
THE TEMPERATURE...DEWPOINT...RELATIVE HUMIDITY AND WIND FIELDS AND
WERE RELIED UPON TO HANDLE THE REMAINDER OF THE FIRST PERIOD
/REST OF TONIGHT/. THE PRECIPITATION CHANCES WERE A LITTLE MORE
DIFFICULT...BUT UTILIZED THE SREF GUIDANCE TO DEPICT THE MOST
LIKELY LOCATION FOR THE DEVELOPMENT OF TRACE PRECIPITATION
OVERNIGHT. THE BEST CHANCES FOR DRIZZLE WILL LIKELY PERSIST OVER
SOUTHERN ILLINOIS...BEFORE DIMINISHING BEFORE DAYBREAK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 325 PM CDT THU MAY 31 2012
SCATTERED THUNDERSTORMS ARE INCREASING THIS MID AFTERNOON...
GENERALLY ALONG AND SOUTHEAST OF THE OHIO RIVER. THE ATMOSPHERE HAS
GROWN VERY UNSTABLE IN THIS REGION DUE TO STRONG DAYTIME HEATING. IN
ADDITION...A PRE FRONTAL BOUNDARY IS MOVING SOUTHEAST ACROSS THE
SAME REGION...AND 0 TO 6 KM BULK SHEAR VALUES ARE RUNNING UP AROUND
40 KTS. THE SHEAR SHOULD LEAD TO SOME ROTATING UPDRAFTS...WITH SFC
BASED LI VALUES RUNNING IN THE -4 TO -8 RANGE. DAMAGING WIND GUSTS
AND HAIL WILL BE THE PRIMARY CONCERNS WITH THIS ACTIVITY...BUT AN
ISOLATED TORNADO OR TWO CANNOT BE RULED OUT. THERE MAY ALSO BE SOME
STORM DEVELOPMENT LATE TODAY AND EARLY THIS EVENING AHEAD OF THIS
BAND OF STORMS. MOST THUNDERSTORM ACTIVITY SHOULD MIGRATE SOUTHEAST
OF THE FORECAST AREA BY AROUND SUNSET THIS EVENING.
BY AROUND THE MIDNIGHT HOUR...SFC WINDS WILL BE FROM THE NW AND THE
ATMOSPHERE SHOULD BE STABLE ENOUGH FOR JUST SHOWERS...WHICH ARE
EXPECTED TO DIMINISH RAPIDLY FROM THE WEST OVERNIGHT BEHIND A COLD
FRONT...WITH A SMALL POSSIBILITY OF SOME WRAPAROUND SHOWERS IN SRN
IL/SWRN IND. AS THE MID/UPPER LEVEL LOW DEPARTS THE AREA TO THE
EAST...WINDS ARE EXPECTED TO STAY STEADY OUT OF THE NW DURING THE
DAY FRI AS CLOUDINESS DIMINISHES. MEASURABLE PCPN IS NOT EXPECTED IN
THE CYCLONIC FLOW OVER THE PAH FORECAST AREA ON SAT THE SAT NIGHT.
ESPECIALLY WITH RECENT ABOVE NORMAL TEMPS...FRI/FRI NIGHT WILL
SEEM MIGHTY COOL...FOLLOWED BY A GRADUAL REBOUND FOR THE LATTER
HALF OF THE WEEKEND.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 325 PM CDT THU MAY 31 2012
THE COMBINATION OF A SURFACE TROF WORKING EASTWARD INTO SOUTHEAST
MISSOURI ALONG WITH AN UPPER LEVEL DISTURBANCE IN THE NORTHWEST FLOW
ALOFT COULD GENERATE SMALL PRECIP CHANCES OVER OUR FAR WESTERN
COUNTIES STARTING SUNDAY AFTERNOON. FROM SUNDAY NIGHT THROUGH MONDAY
NIGHT PRECIP CHANCES WILL MIGRATE NORTH AND EAST ACROSS THE CWA AS
THE OVERALL SYNOPTIC SCENARIO CONTINUES. THROUGH THIS PERIOD
HOWEVER...THE BEST PRECIP CHANCES WILL CONTINUE OVER THE SOUTHWEST
SECTIONS OF OUR CWA.
FROM TUESDAY THROUGH WEDNESDAY NIGHT THE REGION SHOULD REMAIN PRECIP
FREE AS HIGH PRESSURE SLIDES SOUTHWARD ACROSS THE LOWER OHIO VALLEY.
FOR THURSDAY AND BEYOND PRECIP CHANCES RETURN TO THE FORECAST AS
ANOTHER STORM SYSTEM DEVELOPS SOUTHEAST INTO OUR CWA OUT OF THE
NORTHERN PLAINS. WITH THIS SYSTEM PRECIP CHANCES SHOULD AGAIN BE
GREATEST ACROSS THE WESTERN SECTIONS OF OUR CWA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 647 PM CDT THU MAY 31 2012
SHOWER ACTIVITY AND SLOWLY DIMINISHING TSTM ACTIVITY WILL
CONTINUE ACROSS THE REGION FOR A WHILE THIS EVENING...AFFECTING
TERMINALS MAINLY IN WRN KY AND MOST OF SWRN IND. BRIEF IFR VSBYS
AND GUSTY WINDS ABOVE 20 KTS CONTINUE TO BE POSSIBLE IN STORMS...
THROUGH MID EVENING. NWRLY LOW LEVEL WINDS WILL DOMINATE MORE AND
MORE THIS EVENING FROM WEST TO EAST. MVFR CIGS APPEAR POSSIBLE
OVERNIGHT IN THE WRAP AROUND CIRCULATION...LINGERING INTO MID
MORNING ACROSS THE ERN THIRD OF THE REGION.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...SMITH
SHORT TERM...GM/DB
LONG TERM....JP
AVIATION...DB
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
400 AM EDT FRI JUN 1 2012
.SYNOPSIS...
A WARM FRONT WILL LIFT TO THE NORTH THIS MORNING. LOW PRESSURE
OVER THE OHIO VALLEY WILL MOVE NORTHWARD INTO THE GREAT LAKES TODAY.
THIS WILL CAUSE A COLD FRONT TO MOVE ACROSS THE AREA LATE THIS
AFTERNOON AND EVENING. WEAK HIGH PRESSURE BUILDS IN ON SATURDAY.
AN UPPER TROUGH WILL PERSIST OVER THE EASTERN STATES THIS WEEKEND
INTO THE MIDDLE PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AT 07Z...WARM FRONT WAS STRETCHED FROM SOUTHERN VIRGINIA BACK
THROUGH WEST VIRGINIA AND INTO THE OHIO VALLEY WHERE APPROX. 1003MB
LOW PRESSURE WAS LOCATED.
TO THE NORTH OF THE WARM FRONT...AREA OF WARM ADVECTION/ELEVATED
INSTABILITY WAS SUPPORTING SCATTERED SHOWERS ACROSS THE SHENANDOAH
VALLEY AND CENTRAL VIRGINIA FOOTHILLS. RECENT RUNS OF THE HRRR SHOW
SCATTERED SHOWERS LIFTING TO THE NORTHEAST TOWARD THE DC-BALTIMORE
CORRIDOR THROUGH DAYBREAK.
WARM FRONT WILL LIFT TO THE NORTH THROUGHOUT THE DAY...ALTHOUGH
NORTHERN PROGRESSION MAY BE SLIGHTLY SLOWER THAN PREVIOUS FORECASTS
AND THE BOUNDARY MAY NOT MAKE IT NORTH OF THE MASON DIXON LINE UNTIL
CLOSER TO 18Z. CWA IS EXPECTED TO BE WARM SECTORED DURING THE
AFTERNOON WITH TEMPERATURES RISING AOA 80F WITH DEWPOINTS IN THE
LOWER TO MID 60S.
WARM FRONT ITSELF MAY SERVE AS A CONTINUING FOCUS FOR SHOWER
DEVELOPMENT THIS MORNING...AND EVENTUAL THUNDERSTORM DEVELOPMENT AS
THE ATMOSPHERE BECOMES MORE UNSTABLE. SOUTH OF THE BOUNDARY...THERE
COULD BE A RELATIVE LATE MORNING LULL IN PRECIP /AS INDICATED BY THE
HRRR/...BUT LARGER SCALE FORCING WILL INCREASE FROM THE WEST DURING
THE AFTERNOON. IN THE WAKE OF THE WARM FRONT...PRE-FRONTAL TROUGH
AND THEN A COLD FRONT WILL SERVE AS STRONG LIFTING MECHANISMS FOR
FOCUSED THUNDERSTORM DEVELOPMENT THIS AFTERNOON/EVENING. COMBINATION
OF THESE BOUNDARIES MAY LEAD TO SEVERAL WAVES OF SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING...POSSIBLY
MULTICELL/SUPERCELL-TYPE STORMS INITIALLY IN THE AFTERNOON AND THEN
LINEAR STORMS AHEAD OF THE ACTUAL COLD FRONT THIS EVENING.
GIVEN CLOUD COVER THROUGH MUCH OF THE DAY...THERE REMAINS SOME
UNCERTAINTY REGARDING INSTABILITY. INCREASING MOISTURE WILL MAKE A
CONTRIBUTION...AND SOUTH OF THE WARM FRONT SOME BREAKS IN THE CLOUDS
ARE EXPECTED WHICH WILL INCREASE CAPE TO AT LEAST 1K TO 1.5K J/KG
AND PERHAPS HIGHER IN SPOTS THAT ACHIEVE MORE BREAKS. WIND FIELDS
WILL ALSO STRENGTHEN THROUGHOUT THE DAY...INCREASING BULK SHEAR IN
THE AFTERNOON. GIVEN CAPE/SHEAR FORECAST AND STRONG FORCING FROM
AFOREMENTIONED LIFTING MECHANISMS...EXPECT SOME THUNDERSTORMS TO
BECOME SEVERE WITH DAMAGING WINDS. WITH INCREASED SHEAR PROMOTING
HIGHER HELICITY VALUES /ESPECIALLY THOSE DEPICTED BY THE NAM/...THIS
SUGGESTS THAT A FEW TORNADOES MAY BE POSSIBLE AS WELL.
IN ADDITION...AN AXIS OF HIGH THETA-E/HIGH PRECIPITABLE WATER AIR IS
FORECAST AHEAD OF THE FRONT. PRECIPITABLE WATERS ARE FORECAST TO
INCREASE TO 1.5IN TO 1.8IN. THIS MAY LEAD TO HEAVY RAINFALL AND
FLASH FLOODING...ESPECIALLY IF MULTIPLE WAVES OF THUNDERSTORMS
OCCUR.
GRIDS INCLUDE ENHANCED WORDING FOR SEVERE THUNDERSTORMS AND HEAVY
RAINFALL...WITH HWO ALSO HIGHLIGHTING HAZARDOUS WEATHER.
COLD FRONT CATCHES UP TO THE TROUGH THIS EVENING BUT THE FRONTAL
BOUNDARY NEARLY PARALLELING THE UPPER FLOW WILL SLOW DOWN THE
PROGRESSION OF FROPA/PRECIP A LITTLE. MODIFIED POPS/WX/QPF TO
ACCOUNT FOR THIS. SEVERE WEATHER IS EXPECTED TO BE EAST OF THE BAY
BY AROUND MIDNIGHT...BUT THERE MAY BE A PERIOD OF SHOWERS BEHIND
THIS FOR A FEW HOURS. BUT NORTHWEST WINDS BEHIND THE FRONT SHOULD
HELP TO PUSH THE MOISTURE EAST WHERE THE CWA SHOULD BE DRY BY
DAYBREAK.
&&
.SHORT TERM /SATURDAY/...
WEAK SURFACE HIGH PRESSURE BUILDS INTO THE MID ATLANTIC ON SATURDAY.
NORTHWEST WINDS/COLD ADVECTION WILL BRING COOLER AND LESS HUMID
CONDITIONS. MORNING MAY BEGIN WITH A DECENT AMOUNT OF SUNSHINE...BUT
DESPITE DOWNSLOPING FLOW THE PRESENCE OF AN UPPER TROUGH MAY PROMOTE
CUMULUS DEVELOPMENT FOR THE AFTERNOON FOR PARTLY SUNNY SKIES.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE NEXT SEVERAL DAYS OF NEAR AVERAGE TEMPERATURES AND RELATIVELY
COMFORTABLE HUMIDITIES MAY JUST BE ENOUGH TO WASH OUT MEMORIES OF
THE FEW DAYS OF HEAT...CENTERED AROUND THIS PAST WEEKEND. THE COMING
WEEK WILL CERTAINLY BE MORE ACTIVE THAN DURING THE HOT-STRETCH.
AFTER DEPICTING A GOOD CONSENSUS FOR THE NEXT COUPLE OF DAYS...MED
AND LONG RANGE GUIDANCE TAKE DIFFERING SIDES ON WHAT TO DO W/ THE
NEXT SYSTEM. FIRST...THE PARENT UPPER LEVEL SYSTEM ASSOCIATED W/ THE
SYSTEM CURRENTLY APPROACHING THE AREA WILL PIVOT TO OUR NORTH AND
SWING BACK TOWARD THE NEW ENGLAND COAST EARLY NEXT WEEK. THE
OCCLUDING UPPER LOW THAT GETS STUCK OVER ONTARIO WILL TRANSFER THE
REST OF ITS ENERGY TO A DEVELOPING SYSTEM OFF CAPE COD. THIS
TRANSITION WILL ALLOW SOME BATCHES OF RAIN TO SWING BACK DOWN ACROSS
THE MID ATLC SUN AND MON IN BRIEF SCATTERED POCKETS. THE NAM IS MORE
AGGRESSIVE W/ THIS SOLUTION...WHILE THE GFS TENDS TO PULL THE
FEATURE OFF THE COAST...PULLING UP JUST TO OUR NE INSTEAD OF PASSING
OVER THE AREA.
AN INTERESTING SECONDARY LOW PRESSURE SYSTEM DEVELOPS IN LATEST RUN
OF THE GFS. THIS NEXT SYSTEM BEGINS AS A SERIES OF WEAK UPPER WAVES
COMING DOWN FROM THE NRN PLAINS THAT COMBINE AND STRENGTH AS THEY
MOVE SE FROM THE GREAT LAKES REGION. BY THE TIME THIS NEW FEATURE
APPROACHES THE MID ATLC COAST...A RAPID INTENSIFICATION TAKES PLACE
OVER-TOP OUR AREA FROM TUE INTO WED. THIS TYPE OF SOLUTION CREATES
AN POTENT SYSTEM W/ DYNAMIC FORCING BUT ALSO ONE THAT COULD CHANGE
DRAMATICALLY FROM RUN-TO-RUN OVER THE NEXT COUPLE OF DAYS. THE
ECMWF...WHICH IS MORE IN-STEP W/ THE NAM TOWARD THE END OF ITS
CYCLE...BASICALLY KEEPS OUR CURRENT LOW PRESSURE SYSTEM SITTING OFF
THE NEW ENGLAND COAST AND ROTATING IN PLACE FOR THE ENTIRE WORK
WEEK.
WITH EITHER SOLUTION FOR OUR LONG RANGE FORECAST...THERE WILL BE A
DISTINCT LACK OF AN UPPER RIDGE AND THEREFORE NO RETURNING OF THE
HEAT/HUMIDITY - THRU THE CURRENT FORECAST PERIOD.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
MAIN AVIATION IMPACT WILL BE THUNDERSTORMS THIS AFTERNOON AND
EVENING. WARM FRONT IS EXPECTED TO LIFT NORTH OF THE AREA THIS
MORNING WITH A STRAY SHOWER OR TWO. THEN PRE-FRONTAL TROUGH AND COLD
FRONT WILL SERVE AS FOCUSING MECHANISMS FOR NUMEROUS
SHOWERS/THUNDERSTORMS THIS AFTERNOON/EVENING...PERHAPS AS MULTICELLS
THIS AFTERNOON AND THEN A SQUALL LINE THIS EVENING. GIVEN HIGHER CONFIDENCE
OF OCCURRENCE...HAVE MODIFIED VCTS/CB TO PREVAILING TSRA DURING
THE TIME OF THE GREAT PROBABILITY FOR IMPACT. ITS POSSIBLE THAT
TSRA MAY NOT EXTEND FAR ENOUGH INTO THE EVENING AND WOULD NEED
ADJUSTMENT. COLD FRONT LOOKS TO MOVE THROUGH THE HUBS 05Z-07Z WITH
A WIND SHIFT TO THE NORTHWEST. WEAK HIGH PRESSURE BUILDS IN FOR
SATURDAY.
AFTER MOVING OFF FROM THE NEW ENGLAND COAST SAT INTO SUN...THE MAIN
UPPER LOW WILL SWING DOWN SOME SHOWERS AND MID LEVEL CLOUDS BACK
ACROSS THE MID ATLC FROM SRN CANADA. THIS ACTIVITY WILL BE LIGHT AND
INTERMITTENT AT BEST...W/ SOME BREEZY NWLY WINDS AT THE SFC INTO
EARLY NEXT WEEK. SOME UNCERTAINTY IN THE DEPICTION OF A SUBSEQUENT
LOW PRESSURE SYSTEM INTO THE MIDDLE OF NEXT WEEK.
&&
.MARINE...
SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THIS AFTERNOON/TONIGHT.
SOUTHEAST FLOW IS FORECAST TO INCREASE WITH GUSTS AOA 20 KT THIS
AFTERNOON/EVENING AHEAD OF A COLD FRONT. COLD FRONT WILL ALSO BRING
THUNDERSTORMS WHICH MAY PRODUCE STRONG GUSTY WINDS REQUIRING SPECIAL
MARINE WARNINGS. COLD FRONT MOVES THROUGH SHORTLY AFTER 06Z
TONIGHT...WITH A WIND SHIFT TO THE NORTHWEST. ITS POSSIBLE THAT
NORTHWEST WINDS LATE TONIGHT/EARLY SATURDAY MAY BE CLOSE TO SCA
CRITERIA AS WELL...HOWEVER CONFIDENCE IS LOW.
LOW PRESSURE WILL REMAIN OFF THE COAST THRU MUCH OF NEXT WEEK...W/
PERIODIC SCA CONDITIONS EARLY IN THE WEEK.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS WERE RUNNING ABOUT 1/2 FT ABOVE NORMAL OVERNIGHT. WITH
SOUTHEAST WINDS INCREASING...EXPECT ANOMALIES TO INCREASE THROUGHOUT
THE DAY. HIGH TIDE CYCLE THIS AFTERNOON IS THE LOWER ONE...AND EVEN
A 1 FT ANOMALY WOULD NOT PRODUCE MINOR TIDAL FLOODING AT ANNAPOLIS.
HOWEVER...AN ANOMALY OF JUST 3/4 FT WOULD DURING THE SUBSEQUENT HIGH
TIDE CYCLE TONIGHT. BY THAT TIME...COLD FRONTAL PASSAGE WILL HAVE
TURNED WINDS TO THE NORTHWEST BUT AM UNCERTAIN IF WATER WILL BE ABLE
TO BE PUSHED OUT BY THAT TIME. THEREFORE...MINOR TIDAL FLOODING IS
POSSIBLE DURING HIGH TIDE TONIGHT ESPECIALLY AT SENSITIVE
LOCATIONS SUCH AS ANNAPOLIS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EDT SATURDAY FOR
ANZ530>543.
&&
$$
SYNOPSIS...BPP
NEAR TERM...BPP
SHORT TERM...BPP
LONG TERM...GMS
AVIATION...BPP/GMS
MARINE...BPP/GMS
TIDES/COASTAL FLOODING...BPP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
205 AM EDT FRI JUN 1 2012
.SYNOPSIS...
LOW PRESSURE CONSOLIDATING OVER THE OHIO VALLEY DURING THE WEE HOURS
OF THIS MORNING WILL LIFT NORTH ACROSS LAKE ERIE LATER TODAY...THEN
WILL SWING A STRONG FRONT ACROSS THE REGION FRIDAY NIGHT AS IT
CONTINUES TO MOVE NORTH ACROSS ONTARIO. THIS WILL SEND TWO AREAS OF
BENEFICIAL RAIN ACROSS OUR REGION...WHICH COULD TOTAL WELL OVER AN
INCH IN SOME AREAS BY SATURDAY MORNING. COOL AND SOMEWHAT UNSETTLED
CONDITIONS WILL THEN REMAIN IN PLACE FOR THE WEEKEND...ALTHOUGH MUCH
OF THE TIME SHOULD BE RAIN FREE.
&&
.NEAR TERM /THROUGH TODAY/...
CLOUDS WILL GRADUALLY INCREASE FROM WEST TO EAST OVERNIGHT. THE
CULPRIT WILL BE LOW PRESSURE DEVELOPING ACROSS OHIO OVERNIGHT...WHICH
IS FORECAST TO STRENGTHEN AS IT TRACKS NORTHWARD ACROSS LAKE ERIE
AND LAKE HURON LATE FRIDAY. DEVELOPMENT OF THIS LOW WILL BE
DRIVEN BY ENERGY ALOFT...WITH A CLOSED 500 MB LOW APPROACHING FROM
THE MIDWEST DURING THIS TIMEFRAME.
AHEAD OF THE SURFACE LOW...AN ANOMALOUSLY STRONG (4 STD) SOUTHERLY
LOW LEVEL JET WILL MOVE NORTH TOWARD WESTERN NEW YORK LATE
TONIGHT. THIS WILL CAUSE RAIN TO DEVELOP TONIGHT. 18Z RUNS OF THE
NAM/GFS AND THE SEVERAL RUNS OF THE HRRR HAVE TRENDED A TAD SLOWER
WITH THIS...WITH RAIN LIKELY TO REACH FAR WESTERN NEW YORK AROUND
DAYBREAK. WARM AIR ADVECTION WILL BE WEAKER TO THE EAST...SINCE IT
IS FURTHER FROM THE UPPER LOW.
THE POTENT LOW LEVEL JET WILL LIFT ACROSS WESTERN NEW YORK ON
FRIDAY MORNING AND EARLY AFTERNOON. THERE MAY BE A BRIEF BREAK IN
THE RAIN DURING THE DAY FRIDAY...BUT RAIN SHOULD RETURN LATE
AFTERNOON AND INTO FRIDAY EVENING AS THE OCCLUDED FRONT SLOWLY
CROSSES THE REGION FROM WEST TO EAST. IT IS THIS FEATURE WHICH IS
LIKELY TO BRING THE HEAVIEST RAIN. IN ADDITION TO THE STEADY
RAIN...THE LATEST STABILITY INDICES SUGGESTS THAT THERE WILL BE A
CHANCE FOR SOME EMBEDDED THUNDERSTORMS LATER IN THE AFTERNOON AND
EVENING.
HPC`S LATEST QPF GUIDANCE FOR FRIDAY INDICATES A POTENTIAL FOR A
LITTLE OVER AN INCH OF RAIN ACROSS WESTERN NEW YORK AND THE GENESEE
VALLEY...WITH ABOUT ONE THIRD TO THREE QUARTERS OF AN INCH FARTHER
TO THE EAST. DUE TO THE RECENT DRY TREND...THIS RAINFALL SHOULD NOT
CAUSE SIGNIFICANT PROBLEMS...BUT WE WILL HAVE TO KEEP AN EYE ON THE
POTENTIAL FOR HIGHER AMOUNTS IF CONVECTION DOES DEVELOP.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
COLD FRONT STILL SCHEDULED TO CROSS THE REGION FRIDAY NIGHT. AHEAD
OF THE FRONT...WIDESPREAD RAIN AND EMBEDDED THUNDERSTORMS WILL BE
ONGOING. THE UPPER LEVEL TROUGH WILL BE TAKING ON A NEGATIVE TILT
ALLOWING FAVORABLE LOW LEVEL JET DYNAMICS AND IMPRESSIVE MOISTURE
TRANSPORT TO BECOME FOCUSED ALONG AND AHEAD OF THE FRONT ACROSS THE
GENESEE VALLEY/FINGER LAKES FRIDAY EVENING...THEN INTO THE EASTERN
LAKE ONTARIO REGION AFTER MIDNIGHT. RAINFALL AMOUNTS IN EXCESS OF AN
INCH ARE LIKELY IN THESE AREAS. DRY SLOT WILL FOLLOW THE FRONT
WITH A SHARP DECREASE IN OVERALL PRECIPITATION INTENSITY AND
COVERAGE...WITH ONLY SCATTERED COVERAGE AT BEST WITHIN THIS AREA.
DRYING MAY EVEN BE EXTENSIVE ENOUGH TO BRING A BRIEF BIT OF
CLEARING.
GOOD PORTION OF THE AREA LOOKS TO BE UNDER THE INFLUENCE OF THE DRY
SLOT SATURDAY MORNING...BEFORE WRAP AROUND MOISTURE SLOWLY WORKS
INTO THE REGION FROM THE WEST. FOR THE MOST PART...SATURDAY MAY
WIND UP PRECIPITATION FREE FOR MANY AREAS WITH THE BETTER CHANCES
ACROSS THE FAR WEST...BUT PROBABLY NOT LOOKING AT A WASH OUT. COLD
AIR ADVECTION WILL BRING A COOL DAY WITH MOST HIGHS IN THE MID
60S.
MID LEVEL COLD POOL ASSOCIATED WITH THE CLOSED CIRCULATION DROPPING
SOUTHEAST FROM CANADA WILL BRING INCREASING CHANCE FOR SHOWERS
SUNDAY. MOST OF THE ACTIVITY LOOKS TO BE DIURNALLY DRIVEN...AS
MODEL SOUNDINGS SUGGESTING STEEPENING MID LEVEL LAPSE RATES BY
AFTERNOON. ANOTHER COOL DAY WITH MOST HIGHS IN THE MID TO UPPER
60S...ALTHOUGH COULD BE COOLER IF PRECIPITATION DEVELOPS EARLY
ENOUGH IN THE DAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
LATEST DETERMINISTIC MODEL AND ENSEMBLE DATA CONTINUING TO SUGGEST
LITTLE IN THE WAY OF A PATTERN CHANGE DURING THE PERIOD...WITH
GOOD AGREEMENT BETWEEN THE GFS/CANADIAN/ECMWF. THE LARGE SCALE
UPPER LEVEL FLOW IS CONTINUING TO SIGNAL THE NAO BECOMING HIGHLY
NEGATIVE DURING THE PERIOD...WITH THE FORMATION OF AN OMEGA BLOCK
ACROSS THE NORTH ATLANTIC. THIS WILL RESULT IN THE CONTINUATION OF
THE DEEP UPPER TROUGH OVER NEW ENGLAND AND THE CANADIAN MARITIMES.
THIS PATTERN WILL FAVOR BELOW NORMAL TEMPERATURES THROUGH THE
PERIOD...WITH THE CHANCE OF MAINLY DIURNALLY DRIVEN SHOWERS ON THE
WESTERN SIDE OF THE CYCLONIC FLOW ALOFT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
DETERIORATING CONDITIONS WILL BE EXPERIENCED TODAY AND TONIGHT (FRI
NIGHT) AS LOW PRESSURE OVER THE OHIO VALLEY WILL LIFT NORTH AND
SPREAD RAIN AND LOWERING CIGS ACROSS THE REGION. THE DETAILS...
VFR CONDITIONS WILL REMAIN IN PLACE EARLY THIS MORNING AS MAINLY MID
AND HIGH LEVEL MOISTURE WILL CONTINUE TO THICKEN FROM THE SOUTHWEST.
SHOWERS WILL EVENTUALLY WORK ACROSS THE FAR WESTERN COUNTIES...BUT
CIGS AND VSBYS AT KBUF/KIAG AND KJHW WILL REMAIN AT VFR LEVELS. THE
SHOWERS WILL HOLD OFF UNTIL ABOUT 15Z FOR KROC AND 18Z FOR KART.
THE CONCERN THROUGH DAYBREAK THOUGH WILL BE THE PRESENCE OF SOME LOW
LEVEL WIND SHEAR... WITH LIGHT EASTERLY WINDS AT THE SFC BEING OVER
RUN BY 30-35KT SOUTHEST WINDS AT 1500 FT. AFTER DAYBREAK...DIURNAL
MIXING WILL ALLOW FOR A PERCENTAGE OF THESE WINDS TO MIX TO THE SFC.
A 3-6 HOUR BREAK IN THE FIRST ROUND OF STEADIER RAIN WILL WORK FROM
WEST TO EAST ACROSS THE REGION DURING THE MIDDAY AND AFTERNOON. CIGS
WILL LIKELY DROP TO MVFR LEVELS AT THIS TIME WITH GUSTY SFC WINDS IN
PLACE.
AN OCCLUDED FRONT WILL THEN SLOWLY WORK ACROSS ITS WAY TO THE EAST
ACROSS THE FORECAST AREA LATE THIS AFTERNOON AND TONIGHT (FRI NT). A
3-6 HOUR WINDOW OF STEADY MODERATE TO HEAVY RAIN IS FORECAST TO
ACCOMPANY THIS FRONT...WITH MVFR VSBYS AND CIGS LOWERING TO IFR
LEVELS. THERE WILL ALSO BE ANOTHER ROUND OF LLWS THIS EVENING.
LATE TONIGHT (FRI N)...IFR CONDITIONS ARE EXPECTED TO PREVAIL
ACROSS THE MAJORITY OF THE REGION.
OUTLOOK...
SATURDAY...VFR WITH A CHANCE OF SHOWERS.
SUNDAY...VFR/MVFR WITH CHANCE OF SHOWERS.
MONDAY...MAINLY VFR WITH CHANCE OF SHOWERS.
&&
.MARINE...
LOW PRESSURE WILL MOVE NORTH TOWARD THE OHIO VALLEY TONIGHT...THEN
LIFT JUST NORTH OF LAKE ERIE ON FRIDAY. THE INCREASING PRESSURE
GRADIENT AHEAD OF THE LOW WILL CAUSE EASTERLY WINDS TO PICK UP ON
LAKE ERIE AND THE WESTERN END OF LAKE ONTARIO LATER TONIGHT. WHILE
THE HIGHEST WAVES ON LAKE ERIE WILL BE OVER THE CANADIAN
WATERS...THE WINDS WILL SATISFY THE CRITERIA NEEDED FOR A SMALL
CRAFT ADVISORY.
AS THE LOW LIFTS WEST OF LAKES ERIE AND ONTARIO ON FRIDAY...WINDS
AND WAVES WILL SUBSIDE A BIT ON LAKE ERIE...BUT MODEST EAST TO
SOUTHEAST WINDS WILL CONTINUE TO IMPACT LAKE ONTARIO THROUGH THE
THE DAY. HOWEVER...THERE MAY BE BRIEF PERIOD OF STRONGER WINDS ON
LAKE ERIE FRIDAY EVENING AS THE SURFACE LOW TRACKS TO THE WEST OF
THE LAKE WHICH PUSHES AN OCCLUDED FRONT ACROSS THE LAKE. A FEW
HOURS OF 30 KT SOUTHWESTERLY WINDS MAY FOLLOW THE FRONTAL
PASSAGE...WHICH MAY REQUIRE SMALL CRAFT ADVISORIES AS WELL.
INCREASING SOUTHWEST WINDS WILL IMPACT BOTH LAKES ON SATURDAY AS THE
LOW CONTINUES TO LIFT NORTH ACROSS SOUTHERN ONTARIO.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LEZ040-
041.
SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 5 AM
EDT SATURDAY FOR LOZ043-044.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 2 AM EDT
SATURDAY FOR LOZ042.
&&
$$
SYNOPSIS...RSH
NEAR TERM...APFFEL/TJP
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...RSH
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
454 AM CDT FRI JUN 1 2012
.DISCUSSION.../ISSUED AT 428 AM CDT/
SHARPENING SHORTWAVE HARD TO MISS THIS MORNING ACROSS
NORTHEASTERN MONTANA...AND THIS WAVE WILL TRANSECT THE CWA TODAY
AND THIS EVENING...LEADING TO A VERY GOOD CHANCE FOR
RAINFALL...GIVEN THE STRENGTH OF PV ADVECTION...COLLOCATED WITH A
STRONG BELT OF LOWER TO MID LEVEL THETA E ADVECTION. ONE BIG
CHANGE THIS MORNING WAS A LARGE INCREASE TO POPS INTO THE LIKELY
TO CATEGORICAL RANGE WITH SYSTEM. TIMING AGAIN A CONCERN...WITH
MANY EARLIER HRRR RUNS BEING FAIRLY FRANTIC TAKING PRECIP UP TO
THE I29 CORRIDOR BY NOON. LATEST COUPLE HAVE SLOWED UP A BIT...BUT
AGAIN AS WITH THE SYSTEM A COUPLE DAYS AGO...THE DIV Q FIELDS
SUGGEST THAT LEADING PRECIP COULD JUMP AHEAD SOMEWHAT QUICKER THAN
EXPECTED...AND DID PUSH UP INTRODUCTION OF HIGHER POPS A COUPLE
HOURS HEADING EASTWARD THROUGH THE DAY. PRECIP IN ADVANCE OF A
WEAK LEADING WAVE MOVING INTO WESTERN SD ALREADY GETTING FAIRLY
WELL ORGANIZED ACROSS THE WESTERN DAKOTAS. INSTABILITY IS REALLY
FAIRLY MINIMAL...300-500 J/KG THROUGH MAINLY THE WESTERN HALF OF
THE AREA...SO EXPECT THAT THUNDER COVERAGE WILL LIKELY END UP A
CATEGORY OR TWO BELOW THE RAINFALL...BUT WORTHY OF MENTION. NOT
EXPECTING THE DECENT DEEP SHEAR TO HAVE MUCH IMPACT ON
ORGANIZATION AND THEREFORE SEVERE POTENTIAL...WHICH IS VERY VERY
LOW THROUGH THE WEST. OVERALL...THE RAINFALL WILL AGAIN HAVE A
STRONG INFLUENCE ON THE TEMPERATURES TODAY...BOTH KEEPING HIGHS
SOMEWHAT LOWER...AND ALSO IN NONDIURNAL TRENDS.
WAVE ZIPS THROUGH DURING THE EVENING...OUTRUNNING THE BETTER
INSTABILITY AND SHOULD LEAD TO DECREASING COVERAGE TO PRECIPITATION
FAIRLY QUICKLY THIS EVENING AS IT SHIFTS THROUGH MINNESOTA AND IOWA.
WITH EXPECTATION OF CLOUDS HOLDING SOMEWHAT TOUGH FROM NW IA THROUGH
THE I29 CORRIDOR...HAVE KEPT LOWS UP A BIT FROM PREVIOUS.
SATURDAY WILL BE A PEACH OF A DAY WITH SURFACE RIDGE SETTLING ACROSS
THE AREA. SHOULD BE A GOOD DEAL OF SUNSHINE ONCE ANY LINGERING
CLOUDS MIX OUT ALONG I29...AND TEMPERATURES WILL RESPOND MIXING TO
THE MID 70S EAST TO LOWER 80S WEST. HOWEVER...TEMPS REMAIN SOMEWHAT
CHILLY ALOFT...AND 50-70 J/KG MLCAPE DEVELOPS IN THE EAST ON
SATURDAY MIDDAY THROUGH MUCH OF AFTERNOON...BUT WITH THE LARGER
SCALE FAIRLY HOSTILE TO LIFT WITH DEEP SUBSIDENCE FORCING...KEPT
ISOLATED LEVEL POPS CLEAR OF THE FORECAST AND SETTLED ON INCREASING
THE SKYCOVER WITH EXPECTED CUMULUS FIELD DEVELOPING AHEAD OF LOW
LEVEL RIDGE AXIS.
ANOTHER WEAK WAVE WILL CROSS THE REGION...MAINLY TO THE NORTH ON
LATER SATURDAY NIGHT INTO SUNDAY. LOW LEVEL JET WILL STRENGTHEN
MODESTLY...AND WITH ADVERTISED CONVERGENCE POINT ALONG WITH THE
ADVANCE OF ELEVATED MIXED LAYER...COULD GET SOME ROGUE CONVECTION
LATER AT NIGHT THROUGH SD CWA...MAINLY NORTH.
SUNDAY IS STILL A BIT OF A QUANDARY...WITH SOLUTIONS RANGING FROM A
LARGE MCS ACROSS SW MN TO EXTREME WARMTH. SHOULD BE WARMER...
ESPECIALLY WEST AS BUILDING RIDGE ALLOWS WARMER AIRMASS TO SPREAD
EASTWARD. HOWEVER...SOME QUESTION AS TO IMPACT FROM EARLY DAY
CONVECTION TO TEMPS NORTH/EAST...AND WAS SOMEWHAT MORE CONSERVATIVE
IN HEATING FOR THESE LOCATIONS. TEMPERATURES WARM ENOUGH ALOFT THAT
EXPECT THAT FRONTAL BOUNDARY SHOULD REMAIN LARGELY CAPPED TOWARD THE
SOUTHWEST END...BUT AREAS FARTHER NORTHEAST/EAST MAY SEE SOME
RESURGENCE IN DEVELOPMENT HEADING THROUGH THE LATE AFTERNOON AND
EVENING. POPS REFLECT THE LOWER EXPECTATIONS WESTWARD ALONG
BOUNDARY...WHILE MAINTAINING CHANCE LEVELS TO THE EAST. IF
THUNDERSTORM WERE TO GET GOING LATE AFTERNOON AND EVENING...DEEP
LAYER SHEAR WOULD PROVE MARGINAL FOR SOME MINOR SEVERE THREAT.
DURING THE EXTENDED RANGE /MONDAY THROUGH THURSDAY/ EXPECTATIONS ARE
THAT AMPLIFYING BLOCKING RIDGE WILL MORE OR LESS PROTECT THE AREA
FROM PRECIPITATION THREAT. SOME ROGUE SOLUTIONS /NAMELY THE 00Z
ECMWF/ NOW ARE BACKING TROUGH THROUGH THE GREAT LAKES AND TAKING
ENERGY WESTWARD THROUGH RIDGE TO MELD WITH WESTERN TROUGH IN AN
ELONGATED EAST WEST AXIS...WHICH SEEMS HIGHLY UNLIKELY IN THE ARRAY
OF SOLUTIONS...PROBABLY AS MUCH AS THE GFS WITH PUSHY PIECE OF
WESTERN TROUGH MOVING THROUGH THE RIDGE WED/WED NIGHT. GENERALLY...
WITH SURFACE RIDGE NOSING IN FROM NORTH/NORTHEAST...WOULD BELIEVE
THAT SOME SLIGHTLY DRIER AIR WILL FILTER IN...AND WITH LIGHT WINDS
AT LEAST ON TUESDAY MORNING...SAW THIS AS OPPORTUNITY TO FAVOR MUCH
LOWER END OF GUIDANCE...CLOSER TO ENSEMBLE MEAN NUMBERS. HIGHS WILL
MAINLY START IN THE LOWER 80S FOR MOST...BUT SHOULD SEE A SLOW FALL
IN NUMBERS THROUGH MIDWEEK AS A RESULT OF POTENTIALLY GREATER AMOUNT
OF CLOUDS...BUT ALSO A SLOW COOLING OF THE OVERALL AIRMASS AS THE
MODIFIED POLAR AIRMASS SETTLES IN. DID KEEP SOME VERY SMALL POPS
BRUSHING THE FAR WEST OR SOUTHWEST TO ACCOUNT FOR MINIMAL RISK OF
CONVECTION ENCROACHING FROM THE HIGH PLAINS. /CHAPMAN
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS WILL SPREAD ACROSS
THE AREA TODAY...REACHING KHON AROUND 17Z...AND KFSD/KSUX AROUND
19Z. ASSOCIATED CIGS/VSBYS SHOULD MOSTLY BE LOW-END VFR...WITH THE
EXCEPTION OF ANY HEAVIER SHOWERS OR TS ACTIVITY WHEN TEMPORARY
MVFR CONDITIONS ARE POSSIBLE. SHRA/TS ARE EXPECTED TO END AT KHON
BY 23Z...AND AT KFSD/KSUX BETWEEN 00Z-02Z. LIGHT WEST/SOUTHWEST
WINDS WILL INCREASE TO AROUND 10KTS BY MID MORNING...AND THEN
DECREASE TO AOB 5 KTS AFTER 01Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
428 AM CDT FRI JUN 1 2012
.DISCUSSION.../ISSUED AT 428 AM CDT/
SHARPENING SHORTWAVE HARD TO MISS THIS MORNING ACROSS NORTHEASTERN
MONTANA...AND THIS WAVE WILL TRANSECT THE CWA TODAY AND THIS
EVENING...LEADING TO A VERY GOOD CHANCE FOR RAINFALL...GIVEN THE
STRENGTH OF PV ADVECTION...COLLOCATED WITH A STRONG BELT OF LOWER TO
MID LEVEL THETA E ADVECTION. ONE BIG CHANGE THIS MORNING WAS A LARGE
INCREASE TO POPS INTO THE LIKELY TO CATEGORICAL RANGE WITH SYSTEM.
TIMING AGAIN A CONCERN...WITH MANY EARLIER HRRR RUNS BEING FAIRLY
FRANTIC TAKING PRECIP UP TO THE I29 CORRIDOR BY NOON. LATEST COUPLE
HAVE SLOWED UP A BIT...BUT AGAIN AS WITH THE SYSTEM A COUPLE DAYS
AGO...THE DIV Q FIELDS SUGGEST THAT LEADING PRECIP COULD JUMP AHEAD
SOMEWHAT QUICKER THAN EXPECTED...AND DID PUSH UP INTRODUCTION OF
HIGHER POPS A COUPLE HOURS HEADING EASTWARD THROUGH THE DAY. PRECIP
IN ADVANCE OF A WEAK LEADING WAVE MOVING INTO WESTERN SD ALREADY
GETTING FAIRLY WELL ORGANIZED ACROSS THE WESTERN DAKOTAS.
INSTABILITY IS REALLY FAIRLY MINIMAL...300-500 J/KG THROUGH MAINLY
THE WESTERN HALF OF THE AREA...SO EXPECT THAT THUNDER COVERAGE WILL
LIKELY END UP A CATEGORY OR TWO BELOW THE RAINFALL...BUT WORTHY OF
MENTION. NOT EXPECTING THE DECENT DEEP SHEAR TO HAVE MUCH IMPACT ON
ORGANIZATION AND THEREFORE SEVERE POTENTIAL...WHICH IS VERY VERY LOW
THROUGH THE WEST. OVERALL...THE RAINFALL WILL AGAIN HAVE A STRONG
INFLUENCE ON THE TEMPERATURES TODAY...BOTH KEEPING HIGHS SOMEWHAT
LOWER...AND ALSO IN NONDIURNAL TRENDS.
WAVE ZIPS THROUGH DURING THE EVENING...OUTRUNNING THE BETTER
INSTABILITY AND SHOULD LEAD TO DECREASING COVERAGE TO PRECIPITATION
FAIRLY QUICKLY THIS EVENING AS IT SHIFTS THROUGH MINNESOTA AND IOWA.
WITH EXPECTATION OF CLOUDS HOLDING SOMEWHAT TOUGH FROM NW IA THROUGH
THE I29 CORRIDOR...HAVE KEPT LOWS UP A BIT FROM PREVIOUS.
SATURDAY WILL BE A PEACH OF A DAY WITH SURFACE RIDGE SETTLING ACROSS
THE AREA. SHOULD BE A GOOD DEAL OF SUNSHINE ONCE ANY LINGERING
CLOUDS MIX OUT ALONG I29...AND TEMPERATURES WILL RESPOND MIXING TO
THE MID 70S EAST TO LOWER 80S WEST. HOWEVER...TEMPS REMAIN SOMEWHAT
CHILLY ALOFT...AND 50-70 J/KG MLCAPE DEVELOPS IN THE EAST ON
SATURDAY MIDDAY THROUGH MUCH OF AFTERNOON...BUT WITH THE LARGER
SCALE FAIRLY HOSTILE TO LIFT WITH DEEP SUBSIDENCE FORCING...KEPT
ISOLATED LEVEL POPS CLEAR OF THE FORECAST AND SETTLED ON INCREASING
THE SKYCOVER WITH EXPECTED CUMULUS FIELD DEVELOPING AHEAD OF LOW
LEVEL RIDGE AXIS.
ANOTHER WEAK WAVE WILL CROSS THE REGION...MAINLY TO THE NORTH ON
LATER SATURDAY NIGHT INTO SUNDAY. LOW LEVEL JET WILL STRENGTHEN
MODESTLY...AND WITH ADVERTISED CONVERGENCE POINT ALONG WITH THE
ADVANCE OF ELEVATED MIXED LAYER...COULD GET SOME ROGUE CONVECTION
LATER AT NIGHT THROUGH SD CWA...MAINLY NORTH.
SUNDAY IS STILL A BIT OF A QUANDRY...WITH SOLUTIONS RANGING FROM A
LARGE MCS ACROSS SW MN TO EXTREME WARMTH. SHOULD BE WARMER...
ESPECIALLY WEST AS BUILDING RIDGE ALLOWS WARMER AIRMASS TO SPREAD
EASTWARD. HOWEVER...SOME QUESTION AS TO IMPACT FROM EARLY DAY
CONVECTION TO TEMPS NORTH/EAST...AND WAS SOMEWHAT MORE CONSERVATIVE
IN HEATING FOR THESE LOCATIONS. TEMPERATURES WARM ENOUGH ALOFT THAT
EXPECT THAT FRONTAL BOUNDARY SHOULD REMAIN LARGELY CAPPED TOWARD THE
SOUTHWEST END...BUT AREAS FARTHER NORTHEAST/EAST MAY SEE SOME
RESURGENCE IN DEVELOPMENT HEADING THROUGH THE LATE AFTERNOON AND
EVENING. POPS REFLECT THE LOWER EXPECTATIONS WESTWARD ALONG
BOUNDARY...WHILE MAINTAINING CHANCE LEVELS TO THE EAST. IF
THUNDERSTORM WERE TO GET GOING LATE AFTERNOON AND EVENING...DEEP
LAYER SHEAR WOULD PROVE MARGINAL FOR SOME MINOR SEVERE THREAT.
DURING THE EXTENDED RANGE /MONDAY THROUGH THURSDAY/ EXPECTATIONS ARE
THAT AMPLIFYING BLOCKING RIDGE WILL MORE OR LESS PROTECT THE AREA
FROM PRECIPITATION THREAT. SOME ROGUE SOLUTIONS /NAMELY THE 00Z
ECMWF/ NOW ARE BACKING TROUGH THROUGH THE GREAT LAKES AND TAKING
ENERGY WESTWARD THROUGH RIDGE TO MELD WITH WESTERN TROUGH IN AN
ELONGATED EAST WEST AXIS...WHICH SEEMS HIGHLY UNLIKELY IN THE ARRAY
OF SOLUTIONS...PROBABLY AS MUCH AS THE GFS WITH PUSHY PIECE OF
WESTERN TROUGH MOVING THROUGH THE RIDGE WED/WED NIGHT. GENERALLY...
WITH SURFACE RIDGE NOSING IN FROM NORTH/NORTHEAST...WOULD BELIEVE
THAT SOME SLIGHTLY DRIER AIR WILL FILTER IN...AND WITH LIGHT WINDS
AT LEAST ON TUESDAY MORNING...SAW THIS AS OPPORTUNITY TO FAVOR MUCH
LOWER END OF GUIDANCE...CLOSER TO ENSEMBLE MEAN NUMBERS. HIGHS WILL
MAINLY START IN THE LOWER 80S FOR MOST...BUT SHOULD SEE A SLOW FALL
IN NUMBERS THROUGH MIDWEEK AS A RESULT OF POTENTIALLY GREATER AMOUNT
OF CLOUDS...BUT ALSO A SLOW COOLING OF THE OVERALL AIRMASS AS THE
MODIFIED POLAR AIRMASS SETTLES IN. DID KEEP SOME VERY SMALL POPS
BRUSHING THE FAR WEST OR SOUTHWEST TO ACCOUNT FOR MINIMAL RISK OF
CONVECTION ENCROACHING FROM THE HIGH PLAINS. /CHAPMAN
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
VFR CEILINGS EXPECTED ACROSS THE CWA THROUGH 00Z SATURDAY. SCATTERED
SHOWERS AND THUNDERSTORMS WILL SPREAD EAST ACROSS THE AREA AFTER 18Z
WITH VISIBILITY POSSIBLY DROPPING TO NEAR 5 MILES WITH THE STRONGER
SHOWERS. THUNDERSTORMS SHOULD GENERALLY BE OUT OF CWA BY 03Z
SATURDAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1045 PM PDT Thu May 31 2012
.SYNOPSIS...
A warming trend with mostly cloudy skies, breezy conditions and a
chance of showers will sum up the weather through Friday. On
Saturday, a strong and moist cold front will promote widespread
showers and breezy conditions...also ushering in cooler than
normal temperatures for the new work week. A progressive pattern with
a few showers will continue into the work week with the best
chance of widespread showers on or about Monday through Tuesday.
&&
.DISCUSSION...
Evening Update: We are focusing on two mechanisms for pcpn for
the remainder of the evening and overnight periods. The first is
shallow instability...upsloping flow...and weak 300K isentropic
ascent responsible for isolated showers across the Idaho
Panhandle. The second is a strengthening warm front bringing
widespread rain to W WA and into my Cascades and Okanogan Country
overnight.
Addressing the earlier, 00z KOTX sounding indicates steep or nearly
dry adiabatic lapse rates from 840-710mb with CAPE extending
upwards to 530mb. By this time of day, temperatures typically cool
and showers are waning however, with abundant mid and high level
moisture streaming across the region and dewpoints in the
50`s...we have not experienced a whole lot of cooling and with
the combination of ascent noted on the the light veering wind
profile, upsloping flow in the ID mountains, and very little cin
with surface temperatures still in the 60`s, isolated shower
activity continues to blossom across portions of Spokane...
Kootenai...and Shoshone Counties as of 9:45PM PDT. Additional
rainfall with this activity should remain light and generally
near a 0.01" or less.
Further west, a sharp area of darkening via water vapor shows a
well defined shortwave trough swinging around the Gulf of AK low
and quickly approaching 130W. Models appear to have a good handle
on the positioning of this midlevel energy and resultant surface
low deepening along 130W arnd 6z. This has resulted in incr warm
frontal pcpn for Western WA which will be spreading onto the
Cascade Crest close to 6z. The main surface low will take a track
toward the N/NE into W BC lifting the eastern edge of the warm
front across N WA 6-12z which will lead to incr clouds and
possibility for light rain for locations from Mazama to Colville.
The 00z GFS is the only model showing any measurable pcpn with the
01z HRRR indicating light echoes on its composite reflectivity
but little in the way of measurable pcpn away from the immediate
crest. Due to the high moisture content within this subtropical
airmass and response to weak lift Thur morning from a similar
front, we have incr PoPs across the north for the 6-12z period.
We have also included fog near the Sandpoint...Bonners
Ferry...Priest Lake areas where heavier showers were present
earlier this evening.
&&
.AVIATION...
06Z TAFS: Abundant mid and upper-level moisture will continue to
stream into the region under persistent moist westerly flow aloft.
There is a small chance for isold -shra across N ID through the
night but any activity will remain on the very light side. Showers
earlier this aftn have left very moist BL conditions with fog likely
in the valleys for locations N of a line from KSZT-KCQV. A warm
front will spread rain and widespread mtn obscrns into the Cascades
6-12z with light shwrs expanding E along the WA/Canadian early this
morning. The combination of a surface heating and lift along the
warm front Friday aftn will incr -shra chance for most locations
along and north of highway 2. A stronger front will bring incr pcpn
chance shortly aft 6z Friday night. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 53 76 54 70 44 67 / 10 20 30 60 20 10
Coeur d`Alene 51 75 55 69 45 66 / 20 30 50 70 30 10
Pullman 52 76 53 66 43 65 / 20 10 30 70 30 20
Lewiston 56 83 59 75 50 72 / 20 10 40 60 20 20
Colville 50 80 54 77 45 72 / 10 50 50 70 20 10
Sandpoint 49 73 52 70 44 65 / 60 50 50 70 30 20
Kellogg 49 74 51 69 43 67 / 20 50 40 80 60 20
Moses Lake 54 84 57 75 47 72 / 10 10 20 20 10 0
Wenatchee 57 81 57 73 49 72 / 10 10 20 20 10 0
Omak 51 80 52 76 44 73 / 10 30 50 30 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1001 PM PDT Thu May 31 2012
.SYNOPSIS...
A warming trend with mostly cloudy skies, breezy conditions and a
chance of showers will sum up the weather through Friday. On
Saturday, a strong and moist cold front will promote widespread
showers and breezy conditions...also ushering in cooler than
normal temperatures for the new work week. A progressive pattern with
a few showers will continue into the work week with the best
chance of widespread showers on or about Monday through Tuesday.
&&
.DISCUSSION...
Evening Update: We are focusing on two mechanisms for pcpn for
the remainder of the evening and overnight periods. The first is
shallow instability...upsloping flow...and weak 300K isentropic
ascent responsible for isolated showers across the Idaho
Panhandle. The second is a strengthening warm front bringing
widespread rain to W WA and into my Cascades and Okanogan Country
overnight.
Addressing the earlier, 00z KOTX sounding indicates steep or nearly
dry adiabatic lapse rates from 840-710mb with CAPE extending
upwards to 530mb. By this time of day, temperatures typically cool
and showers are waning however, with abundant mid and high level
moisture streaming across the region and dewpoints in the
50`s...we have not experienced a whole lot of cooling and with
the combination of ascent noted on the the light veering wind
profile, upsloping flow in the ID mountains, and very little cin
with surface temperatures still in the 60`s, isolated shower
activity continues to blossom across portions of Spokane...
Kootenai...and Shoshone Counties as of 9:45PM PDT. Additional
rainfall with this activity should remain light and generally
near a 0.01" or less.
Further west, a sharp area of darkening via water vapor shows a
well defined shortwave trough swinging around the Gulf of AK low
and quickly approaching 130W. Models appear to have a good handle
on the positioning of this midlevel energy and resultant surface
low deepening along 130W arnd 6z. This has resulted in incr warm
frontal pcpn for Western WA which will be spreading onto the
Cascade Crest close to 6z. The main surface low will take a track
toward the N/NE into W BC lifting the eastern edge of the warm
front across N WA 6-12z which will lead to incr clouds and
possibility for light rain for locations from Mazama to Colville.
The 00z GFS is the only model showing any measurable pcpn with the
01z HRRR indicating light echoes on its composite reflectivity
but little in the way of measurable pcpn away from the immediate
crest. Due to the high moisture content within this subtropical
airmass and response to weak lift Thur morning from a similar
front, we have incr PoPs across the north for the 6-12z period.
We have also included fog near the Sandpoint...Bonners
Ferry...Priest Lake areas where heavier showers were present
earlier this evening.
&&
.AVIATION...
00Z TAFS: Abundant mid and upper-level moisture will continue to
stream into the region under persistent westerly flow aloft. Across
SE WA and the lower ID Panhandle weak warm advection will keep a
shield of stable pcpn going through roughly 02-03z. For NE WA and N
ID...breaks in the midlevel clouds has allowed for convective
showers and isold -tsra mainly east of a line frm KGEG-KCQV. Brief
MVFR cigs will be possible under the heavier showers. This activity
will also persist into the evening hrs...with improving conditions
accompanying sunset. Light SW flow will keep the threat for showers
and mtn obscurations for a majority of the ID Panhandle into Fri
morning. The combination of a surface heating and another
warm front passage on Friday aftn will bring the threat for
additional light -shra across most terminals. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 53 76 54 70 44 67 / 10 20 30 60 20 10
Coeur d`Alene 51 75 55 69 45 66 / 20 30 50 70 30 10
Pullman 52 76 53 66 43 65 / 20 10 30 70 30 20
Lewiston 56 83 59 75 50 72 / 20 10 40 60 20 20
Colville 50 80 54 77 45 72 / 10 50 50 70 20 10
Sandpoint 49 73 52 70 44 65 / 60 50 50 70 30 20
Kellogg 49 74 51 69 43 67 / 20 50 40 80 60 20
Moses Lake 54 84 57 75 47 72 / 10 10 20 20 10 0
Wenatchee 57 81 57 73 49 72 / 10 10 20 20 10 0
Omak 51 80 52 76 44 73 / 10 30 50 30 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1144 PM CDT THU MAY 31 2012
.SHORT TERM...TONIGHT THROUGH SUNDAY
304 PM CDT THU MAY 31 2012
FORECAST CHALLENGES INCLUDE LINGERING SHOWERS INTO THIS
EVENING...THEN CLEARING AND FOG POTENTIAL OVERNIGHT/EARLY FRIDAY
MORNING. ANOTHER CHALLENGE WILL BE THE POTENTIAL FOR REDEVELOPMENT
OF ISOLATED SHOWERS FRIDAY.
CURRENT WATER VAPOR IMAGERY COMBINED WITH 500 MB RAP ANALYSIS SHOW
DEEP MID-LEVEL TROUGH ROTATING SOUTHEAST TROUGH WI/SOUTHERN WI. COLD
AIR ALOFT/LINGERING MID-LEVEL FRONTOGENESIS ASSOCIATED WITH THE
TROUGH WAS PRODUCING SCATTERED SHOWER ACTIVITY ACROSS PORTIONS OF
THE FORECAST AREA. OTHERWISE...CLOUD COVER WAS PRETTY EXTENSIVE
ACROSS THE AREA AND THIS WAS HOLDING TEMPERATURES DOWN IN THE MID/UPPER
50S WHICH IS SOME 20 DEGREES BELOW NORMAL.
31.12Z NCEP MODEL SUITE ALONG WITH THE 31.09Z SREF SHOWING GOOD
AGREEMENT WITH OVERALL SYNOPTIC SETUP THROUGH THE SHORT TERM.
FOR TONIGHT...WILL SEE THAT MID-LEVEL TROUGH MORPH INTO A CLOSED LOW
AND MOVE EAST TOWARD LAKE MICHIGAN THROUGH THE OVERNIGHT HOURS.
APPEARS A FEW DEFORMATION AREA -SHRA WILL LINGER ACROSS THE SOUTH
INTO THE EARLY EVENING HOURS...BUT THEN SHOULD DISSIPATE AROUND 8-9
PM. THE REST OF TONIGHT WILL SEE SLOWLY CLEARING SKIES FROM
NORTHWEST TO SOUTHEAST. CLEARING SKIES/LIGHT WINDS/FAIRLY MOIST
LOWER BOUNDARY LAYER WILL LEAD TO THE POTENTIAL FOR SOME FOG.
MITIGATING FACTOR TO WIDESPREAD FOG WILL BE LIGHT NORTHERLY
COMPONENT TO THE WIND WITH SPEEDS AROUND 10KT AT 500-1000AGL. KEPT
AREAS OF FOG LIMITED TO MISSISSIPPI/WISCONSIN RIVER VALLEYS WHERE
BETTER DECOUPLING OF THE WINDS WILL TAKE PLACE. OTHERWISE...LOOK FOR
OVERNIGHT LOWS ACROSS THE AREA IN THE UPPER 30S IN FAVORED
LOWER-LYING COLD AREAS...TO THE LOWER/MID 40S ELSEWHERE.
ON FRIDAY...THE CLOSED LOW WILL CONTINUE TO DEEPEN AND MOVE SLOWLY
EAST INTO LOWER MICHIGAN. CYCLONIC FLOW/COLD POOL ALOFT WILL RESIDE
OVER OUR AREA WITH STEEP 0-3KM TEMPERATURE LAPSE RATES IN THE
8.5-9C/KM RANGE. NAM ALSO SHOWING 0-3KM MUCAPE AROUND 300J/KG. THIS
SHOULD BE SUFFICIENT FOR EXTENSIVE CUMULUS/TOWERING CUMULUS FIELD
OVER THE FORECAST AREA ALONG WITH ISOLATED SHOWER ACTIVITY. LOOK FOR
HIGHS FRIDAY UNDER THE COLD POOL ALOFT TO TOP OFF IN THE 65-70
DEGREE RANGE. A FEW LINGERING -SHRA STILL POSSIBLE ALONG/NORTHEAST
OF I-94 EARLY FRIDAY EVENING. SCATTERED SHOWERS ALSO POSSIBLE
MAINLY ALONG AND WEST OF THE MISSISSIPPI RIVER FRIDAY NIGHT AS A
WEAK MID-LEVEL TROUGH DROPS SOUTHEAST FROM THE DAKOTAS INTO IA.
FOR SATURDAY...THE CLOSED LOW MOVES INTO EASTERN UPPER MI WITH COLD
CYCLONIC FLOW ALOFT LINGERING ACROSS OUR AREA. THE NAM SHOWS 0-3KM
MUCAPE INCREASING INTO THE 1000-1400J/KG RANGE WHILE 0-1KM ML CAPE
AROUND 500J/KG. THIS WILL LEAD TO ANOTHER DAY OF EXTENSIVE
CUMULUS/TOWERING CUMULUS FIELD ALONG WITH SCATTERED SHRA AND A FEW
THUNDERSTORMS. OTHERWISE...HIGHS SATURDAY ANTICIPATED TO TOP OFF
AGAIN IN THE 65-70 DEGREE RANGE. LOOK FOR THE CONVECTION/CLOUDS TO
DISSIPATED BY EARLY EVENING AS THE LOW/COLD POOL ALOFT MOVES FARTHER
EAST TOWARD LAKE HURON AND RIDGING BUILDS IN FROM THE NORTHERN
PLAINS.
WILL GO DRY ON SUNDAY AS MODELS ARE A BIT SLOWER WITH A MID-LEVEL
TROUGH TOPPING THE RIDGE OVER THE DAKOTAS/CENTRAL PLAINS. WILL
HOWEVER LIKELY SEE AN INCREASE IN MID-HIGH LEVEL CLOUDINESS IN
ADVANCE OF THIS FEATURE.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
304 PM CDT THU MAY 31 2012
31.12Z GFS/ECMWF SHOW A RATHER BLOCKY PATTERN SETTING UP THROUGH THE
PERIOD WITH TROUGHS RESIDING OVER WEST/EAST COASTS AND RIDGE OF HIGH
PRESSURE GETTING PINCHED OVER THE CENTRAL CONUS. SHRA/TS CHANCES
WILL BE SEEN SUNDAY NIGHT THROUGH MONDAY AS A WEAKENING MID-LEVEL
TROUGH TOPS THE RIDGE OVER THE DAKOTAS AND HEADS TOWARD THE UPPER
MISSISSIPPI RIVER VALLEY. FORCING NOT VERY IMPRESSIVE WITH THIS
FEATURE SO WILL CONTINUE WITH SMALLER-END CHANCES FOR NOW. NARROW
RIDGE OF HIGH PRESSURE LOOKS TO KEEP THE AREA DRY THROUGH THE
REMAINDER OF THE PERIOD. TEMPERATURES EXPECTED TO BE MORE SEASONABLE
MONDAY THROUGH THURSDAY AS WELL WITH HIGHS IN THE MID 70S TO AROUND
80.
&&
.AVIATION...THROUGH 06Z SATURDAY
1143 PM CDT THU MAY 31 2012
STILL EXPECTING VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD.
CLOUDS HAVE REMAINED OVER THE AREA LONGER THAN EXPECTED THIS
EVENING. THIS HAS CUT DOWN ON THE AMOUNT OF TIME THAT RADIATIONAL
COOLING CAN OCCUR AND THUS HAS LIKELY CUT DOWN ON THE PROBABILITY
THAT FOG WILL FORM AT KLSE. THE 01.00Z NAM STILL SHOWS THE
POTENTIAL FOR SOME FOG TO FORM LATE TONIGHT AS THE TEMP/DEW POINT
COME TOGETHER AND WILL MAINTAIN THE PATCHY FOG. OTHERWISE...SHOULD
SEE SOME CUMULUS CLOUDS DEVELOP BY LATE MORNING OR EARLY AFTERNOON
AS STEEP LAPSE RATES DEVELOP UNDER CYCLONIC FLOW ALOFT. COULD BE
SOME ISOLATED SHOWERS AROUND IN THE AFTERNOON BUT COVERAGE IS NOT
EXPECTED TO BE ENOUGH TO WARRANT ANY INCLUSION IN THE FORECAST AT
THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
304 PM CDT THU MAY 31 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS MIAMI FL
1101 AM EDT FRI JUN 1 2012
.UPDATE...
NO MAJOR UPDATES WERE NECESSARY THIS MORNING AS THE PREVIOUS
FORECAST PACKAGE REMAINS ON TRACK. THE LATEST RADAR LOOP SHOWED
THE BULK OF THE HEAVIER RAINFALL REMAINING OFF THE COAST OVER THE
ATLANTIC WATERS AND A LARGE AREA WITH MAINLY LIGHT RAIN OR
SPRINKLES CONTINUING OVER THE EASTERN HALF OF THE SOUTH FLORIDA
PENINSULA FROM PALM BEACH TO MIAMI-DADE. HERE ARE SOME TOTALS THUS
FAR FROM A FEW AREAS OF INTEREST:
24 HR TOTALS (8AM YESTERDAY THROUGH 8 AM THIS MORNING):
DOWNTOWN MIAMI: ~1.5"
BROWARD (SOUTHERN): 2.38"
NAPLES/GULF COAST: 0.10"
LAKE REGION: 0.10-0.20"
CENTRAL/NORTHERN BROWARD: 1-2"
DORAL AREA: AROUND 3"
ANOTHER LARGE BATCH OF HEAVY SHOWERS AND THUNDERSTORMS THAT WAS
JUST WEST OF KEY WEST AS OF 1030 AM THIS MORNING SHOULD BEGIN TO
SPREAD NORTHEAST ACROSS THE SOUTHERN HALF OF THE LOCAL AREA
THROUGH THE AFTERNOON PERIOD. THE LATEST HRRR CYCLE GENERALLY LINES
UP WELL WITH THIS CURRENT PATTERN AND QUICKLY BEGINS TO DEVELOP
MORE ACTIVITY ACROSS THE AREAS FROM NAPLES TO THE LAKE REGION
OVER THE NEXT FEW HOURS AND THROUGH THE REST OF THE DAY. THE
LATEST HPC RAINFALL FORECAST INDICATES ADDITIONAL ACCUMULATIONS
REACHING THE 3 TO 5 INCH RANGE ACROSS SOUTH FLORIDA. AS TYPICALLY
OBSERVED DURING THESE EVENTS...LOCALLY HIGHER AMOUNTS WILL
CERTAINLY BECOME A POSSIBILITY WHERE THE HEAVIER ACTIVITY BECOMES
CONCENTRATED.
SATURDAY THROUGH SUNDAY...THERE REMAINS SOME DEGREE OF UNCERTAINTY
AS TO HOW QUICKLY THE RAINFALL WILL CLEAR EAST OF THE LOCAL AREA
THROUGH THE DAY SATURDAY, MAINLY DUE TO SOME NOTABLE TIMING
DIFFERENCES BETWEEN THE NUMERICAL MODEL SOLUTIONS. IF THE SLOWER
SOLUTION VERIFY, ELEVATED RAINFALL PROBABILITIES WILL PERSIST WELL
INTO SATURDAY BEFORE TRENDING DOWN, WHEREAS, IF THE FASTER
SOLUTION VERIFIES, DRYING COULD BEGIN EARLY SATURDAY FROM
NORTHWEST TO SOUTHEAST. 85/AG
&&
.PREV DISCUSSION... /ISSUED 739 AM EDT FRI JUN 1 2012/
UPDATE...
SHOWERS AND EMBEDDED THUNDERSTORMS DIMINISHED OVER THE NORTHERN HALF
OF THE REGION DUE TO SOME LOW LEVEL DIVERGENCE. HOWEVER...WITH SOUTH
AND SOUTHWESTERLY FLOW...SHOWERS AND EMBEDDED THUNDERSTORMS WERE
BEGINNING TO MOVE BACK INTO SOUTH FLORIDA. WITH DEEP MOISTURE...A
SUBTROPICAL JET...AND AN UPPER LEVEL SHORTWAVE EXPECTED TO PUSH
ACROSS THE FLORIDA PENINSULA TODAY. GUIDANCE CONTINUES TO INDICATE
PREVAILING IFR AND EVEN LIFR CONDITIONS FOR 4-8 HOURS THIS
AFTERNOON. HOWEVER...WITH LACK OF HEATING KEPT CONDITIONS IN THE
MVFR RANGE. GUIDANCE ALSO INDICATES AN EAST COAST SEA BREEZE...BUT
WITH CLOUD COVER AND RAIN...WINDS MAY BE VARIABLE...BUT OVERALL IN A
WEST TO SOUTHWESTERLY DIRECTION THROUGH THE DAY. THE UPPER LEVEL
TROUGH IS EXPECTED TO MOVE ACROSS THE FLORIDA PENINSULA
TONIGHT...WITH VIS/CIGS IMPROVING AFTER 06Z.
AVIATION...BNB/AK
PREV DISCUSSION... /ISSUED 424 AM EDT FRI JUN 1 2012/
.FLOOD WATCH FOR ALL OF SOUTH FLORIDA THROUGH MIDNIGHT...
.A FEW STRONG THUNDERSTORMS POSSIBLE THROUGH THIS EVENING...
DISCUSSION...A MID TO UPPER LEVEL TROUGH WILL STEADILY MOVE EASTWARD
TODAY WHILE GRADUALLY DEEPENING IN RESPONSE TO AT LEAST ONE
STRONG SHORTWAVE OVER THE GULF OF MEXICO. MEANWHILE, A SEPARATE
SHORTWAVE WILL TRAVEL FROM THE YUCATAN NORTHEAST INTO SOUTHWEST
FLORIDA BY THIS AFTERNOON. THE LATEST WATER VAPOR IMAGERY
CONTINUES TO SHOW CONSIDERABLE AMOUNTS OF MOISTURE, IN
ASSOCIATION WITH THESE FEATURES, OVER MUCH OF THE EASTERN GULF OF
MEXICO AND ACROSS THE FLORIDA PENINSULA. SOME EMBEDDED DEEP
CONVECTION ALSO EXTENDS FROM BROWARD COUNTY SOUTHWEST INTO THE
YUCATAN PENINSULA.
PRECIPITABLE WATERS HAVE INCREASED TO AT LEAST 2 INCHES ACROSS
MUCH OF THE REGION, ALTHOUGH A SUBTLE LAYER OF DRY AIR STILL
PERSISTS OVER THE FAR SOUTHEAST AND ADJACENT ATLANTIC WATERS.
BUT, AS SYNOPTIC AND LARGE SCALE FORCING INCREASE THIS MORNING
ALONG WITH VORTICITY ADVECTION AND SPEED CONVERGENCE IN THE LOWER
LEVELS, THE ENVIRONMENT WILL BECOME PRIMED FOR THE DEVELOPMENT OF
ADDITIONAL SHOWERS AND THUNDERSTORMS. DEEP SOUTHERLY FLOW AND
MOISTURE ADVECTION WILL ENHANCE ISENTROPIC LIFT, WHICH WILL
INCREASE BOTH THE COVERAGE AND INTENSITY OF PRECIPITATION. ALSO,
THE RIGHT REAR QUADRANT (80-90 KT) OF AN UPPER JET WILL LIE JUST
TO OUR NORTH ACROSS CENTRAL FLORIDA BY LATE MORNING, RESULTING IN
SIGNIFICANT DIFFLUENCE ALOFT. DEPENDING ON THE AMOUNT OF LOW AND
MID LEVEL INSTABILITY THAT CAN MATERIALIZE, A FEW STRONG
THUNDERSTORMS ARE ALSO POSSIBLE, ESPECIALLY BY LATE MORNING
THROUGH THIS EVENING. AN ISOLATED TORNADO ALSO CANNOT BE RULED
OUT. AREAL AVERAGE RAINFALL AMOUNTS THROUGH THIS EVENING WILL
RANGE FROM 2 TO 4 INCHES WITH LOCALLY HIGHER AMOUNTS QUITE
LIKELY. THE HEAVIEST AND MOST ORGANIZED RAINFALL WILL GRADUALLY
DIMINISH THIS EVENING, GENERALLY FROM NORTHWEST TO SOUTHEAST.
THE LATEST GUIDANCE SHOWS THE MID TO UPPER LEVEL TROUGH MOVING
INTO THE WESTERN ATLANTIC BY MIDDAY SATURDAY AS A DEEP LAYER
RIDGE BUILDS AND EXPANDS TO OUR SOUTHEAST. THIS SHOULD INDUCE
INCREASING AMOUNTS OF SUBSIDENCE, WITH A GRADUAL REDUCTION IN
PRECIPITATION CHANCES. IT SHOULD BE NOTED, HOWEVER, THAT SOME
GUIDANCE IS STILL A BIT SLOWER IN MOVING THE TROUGH TO THE EAST,
WHICH COULD RESULT IN LINGERING SHOWERS AND STORMS OVER AT LEAST
SOUTHEAST PORTIONS OF THE REGION THROUGH MUCH OF THE DAY
SATURDAY. BY SUNDAY, ONLY ISOLATED SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED, ESPECIALLY DURING THE AFTERNOON AND
EVENING, MAINLY IN RESPONSE TO SEA BREEZE DEVELOPMENT.
A LOW LEVEL RIDGE AXIS WILL ESTABLISH ITSELF OVER SOUTH FLORIDA
BY MONDAY AND REMAIN NEARLY STATIONARY THROUGH THURSDAY, WITH
TROUGHING OVER THE SOUTHEAST STATES. THIS WILL BRING AN EXTENDED
PERIOD OF MAINLY WEST TO SOUTHWESTERLY FLOW, WITH THE WARMEST
DAYTIME TEMPS OVER EASTERN AREAS. SUFFICIENT MOISTURE COMBINED
WITH DAILY SEA BREEZE FORMATION WILL BE ENOUGH TO RESULT IN
ISOLATED TO SCATTERED STORMS EACH AFTERNOON.
AVIATION...06Z ISSUANCE...SOUTHERLY FLOW AND MOISTURE TRANSPORT
FROM WESTERN CUBA TOWARD KEY WEST IN ADDITION TO A WEAK SFC
BOUNDARY AND 50 KNOT SUBTROPICAL JET IS LEADING TO A LINE OF
THUNDERSTORMS OVER MAINLAND MONROE AND THE ADJACENT GULF WATERS.
THIS ACTIVITY IS EXPECTED TO PUSH NORTHWARDS TOWARD KAPF OVER THE
NEXT SEVERAL HOURS...WITH PREVAILING MVFR CONDITIONS EXPECTED.
RAIN SHOULD CLEAR OUT ACROSS THE SOUTHEAST TAF SITES INCLUDING
MIA...TMB...OPF NORTHWARD TOWARDS KFLL OVER THE NEXT SEVERAL
HOURS AS THIS ACTIVITY LIFTS NORTHWARD. HOWEVER...LEFT VCSH IN
THE TAFS IN CASE A FEW SHOWERS DECIDE TO DEVELOP. MVFR CIGS HAVE
DEVELOPED ACROSS THE SOUTHEAST TAF SITES...AND IT IS POSSIBLE
THIS COULD PREVAIL THROUGH THE OVERNIGHT HOURS. AS A SHORTWAVE
TROUGH OVER THE CENTRAL GULF MOVES TOWARDS THE FLORIDA PENINSULA
THIS AFTERNOON...HEAVY RAINFALL WITH EMBEDDED THUNDERSTORMS ARE
POSSIBLE. GUIDANCE HAS PREVAILING IFR VIS AND MVFR CIGS FOR 4-8
HOURS ACROSS ALL TAF SITES. ATTM...KEPT PREVAILING MVFR CIGS AND
VIS...BUT IFR AND EVEN LIFR CONDITIONS ARE POSSIBLE IN HEAVY RAIN
AND/OR THUNDERSTORMS. MODEL GUIDANCE DIFFERS ON HOW QUICKLY THE
TROUGH WILL MOVE THROUGH FLORIDA AND HOW QUICKLY THE DEEPER
MOISTURE WILL GET PUSHED TO THE SOUTH AND EAST. SO IT IS POSSIBLE
THAT THE PREVAILING MVFR VIS/CIG COULD CONTINUE THROUGH THE END
OF THE TAF PERIOD...ESPECIALLY FOR THE SOUTHEAST TAF SITES.
MARINE...SOUTHERLY WINDS WILL INCREASE SLIGHTLY TODAY AND THEN
A BIT MORE BY SATURDAY AS A FRONTAL BOUNDARY APPROACHES FROM THE
NORTHWEST. SCATTERED TO NUMEROUS SHOWERS WITH ISOLATED
THUNDERSTORMS WILL CONTINUE INTO SATURDAY, WHICH COULD LEAD TO
PERIODS WITH GUSTY WINDS AND CHOPPIER CONDITIONS. DRIER
CONDITIONS AND LIGHT WEST NORTHWEST WINDS ARE EXPECTED BY SUNDAY.
FIRE WEATHER...NO SIGNIFICANT CONCERNS AS CONSIDERABLE
MOISTURE WILL REMAIN IN PLACE OVER THE NEXT FEW DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 82 71 88 74 / + 60 40 20
FORT LAUDERDALE 83 75 88 76 / + 60 40 20
MIAMI 84 75 89 76 / + 60 40 30
NAPLES 82 73 88 74 / + 60 30 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH THIS EVENING FOR COASTAL BROWARD-COASTAL
COLLIER-COASTAL MIAMI DADE-COASTAL PALM BEACH-FAR SOUTH
MIAMI DADE-GLADES-HENDRY-INLAND BROWARD-INLAND COLLIER-
INLAND MIAMI DADE-INLAND PALM BEACH-MAINLAND MONROE-METRO
BROWARD-METRO MIAMI DADE-METRO PALM BEACH.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION
NWS WICHITA KS
606 AM CDT FRI JUN 1 2012
.AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
LIFT/MOISTENING WITHIN NW-SE ORIENTED MID-LEVEL BAROCLINIC ZONE
SHOULD ALLOW SHOWERS TO SPREAD SOUTHEAST INTO CENTRAL/SOUTH
CENTRAL KS THIS MORNING...BEFORE SHIFTING ACROSS EASTERN KS THIS
AFTERNOON. LAPSE RATES/INSTABILITY APPEAR QUITE MARGINAL AND WILL
LEAVE THUNDER OUT OF TAFS FOR NOW. CEILINGS/VISIBILITIES EXPECTED
TO BE VFR. CLEARING FROM WEST TO EAST EXPECTED THIS EVENING.
JMC
&&
.PREV DISCUSSION... /ISSUED 326 AM CDT FRI JUN 1 2012/
DISCUSSION...
THE MAIN FORECAST CHALLENGES ARE THE MULTIPLE CHANCES FOR
PRECIPITATION THROUGH THE FORECAST.
SYNOPSIS:
THE MAIN UPPER LEVEL DISTURBANCE ACROSS THE CONUS IS MOVING EAST
OVER THE GREAT LAKES THIS MORNING LEAVING THE CENTRAL PLAINS UNDER
NORTHWEST FLOW. RIPPLES IN THE NORTHWEST FLOW HAVE HELPED TO
DEVELOP SCATTERED LIGHT SHOWERS ACROSS WESTERN KANSAS WHICH WILL
EVENTUALLY BE THE MAIN CONCERN FOR WEATHER TODAY. DESPITE THESE
LIGHT SHOWERS OVER WESTERN KANSAS...EASTERN KANSAS IS UNDER MOSTLY
CLEAR SKIES THIS MORNING WITH SURFACE HIGH PRESSURE MOVING
OVERHEAD. WINDS ARE LIGHT AND VARIABLE AND TEMPERATURES ARE IN THE
40S ACROSS THE AREA.
TODAY - SUNDAY:
A RIPPLE IN THE NORTHWESTERLY FLOW IS AND WILL CONTINUE TO BE THE
FOCUS FOR PRECIPITATION DEVELOPMENT TODAY. THE NAM/GFS/HRRR ALL
CONTINUE TO SHOW SHOWER AND THUNDERSTORM DEVELOPMENT THROUGHOUT THE
DAY TODAY. THE HRRR SEEMS TO HAVE A DECENT HANDLE OF CURRENT
TRENDS...AND THAT GIVES CONFIDENCE TO ITS SOLUTION...DEVELOPING
PRECIPITATION ACROSS CENTRAL KANSAS LATER THIS MORNING. THESE
SHOWERS AND THUNDERSTORMS WILL MOVE EASTWARD ACROSS THE STATE TODAY.
THE OVERCAST SKIES AND RAIN WILL HELP KEEP TEMPERATURES DOWN AND
HAVE DECREASED HIGH TEMPS SLIGHTLY TO ACCOUNT FOR THIS. TEMPS WILL
BE ABOUT 10-15 DEGREES BELOW NORMAL FOR EARLY JUNE.
SATURDAY SHOULD REMAIN DRY AND WARMER IN THE WAKE OF THE SYSTEM
TODAY...BUT PRECIPITATION CHANCES WILL RETURN EARLY SUNDAY MORNING
AS A DISTURBANCE UNDERCUTS THE UPPER LEVEL RIDGE AND APPROACHES THE
STATE. HAVE KEPT PRECIPITATION CHANCES THROUGH SUNDAY AND KNOCKED
MAX TEMPS DOWN SLIGHTLY WITH THE CLOUD COVER AND RAIN CHANCES.
MONDAY - THURSDAY:
UPPER LEVEL RIDGING WILL BUILD IN FOR THE FIRST WEEK IN JUNE. THE
MEDIUM RANGE GUIDANCE IS SOMEWHAT SIMILAR WITH THE EXTENDED
FORECAST...BUT THEY ARE CURRENTLY SHOWING SMALL DISTURBANCES
UNDERCUTTING THE RIDGE AND BRINGING CHANCES FOR PRECIP. WITH THE
NORTHWEST FLOW AND THESE DISTURBANCES CANNOT RULE OUT THE CHANCES
FOR PRECIPITATION...BUT CONFIDENCE ON TIMING AND COVERAGE IS LOW.
HAVE MAINTAINED MODEL CONSENSUS THROUGH THE EXTENDED FOR NOW. THE
BEST CHANCE FOR WIDESPREAD PRECIP DOES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY...BUT WILL NEED TO WATCH THIS AS THE FORECAST
EVOLVES. TEMPERATURES WILL GENERALLY WARM INTO THE UPPER 80S AND
LOW 90S THROUGH THE EXTENDED FORECAST.
BILLINGS
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 67 54 83 65 / 40 20 10 20
HUTCHINSON 67 53 83 64 / 40 10 10 20
NEWTON 65 52 82 64 / 40 10 10 20
ELDORADO 65 52 81 63 / 40 20 10 20
WINFIELD-KWLD 68 55 82 65 / 40 30 10 30
RUSSELL 69 53 83 64 / 40 10 10 20
GREAT BEND 70 53 84 63 / 40 10 10 20
SALINA 66 51 83 63 / 40 10 0 20
MCPHERSON 66 52 83 64 / 40 10 10 20
COFFEYVILLE 69 53 81 63 / 30 20 10 20
CHANUTE 67 52 81 62 / 30 10 10 10
IOLA 67 51 81 62 / 20 10 0 10
PARSONS-KPPF 68 52 81 63 / 30 20 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
626 AM EDT FRI JUN 1 2012
.SYNOPSIS...
LOW PRESSURE OVER KENTUCKY WILL INTENSIFY AND MOVE NORTHWARD INTO
THE GREAT LAKES TODAY. THE LOW WILL PUSH A COLD FRONT THROUGH THE
REGION BY LATER THIS EVENING. IN ADVANCE OF THE FRONT,
THUNDERSTORMS WILL DEVELOP THIS AFTERNOON. SOME STORMS COULD BE
SEVERE WITH STRONG GUSTY WINDS AND HAIL. THE LOW PRESSURE SYSTEM
WILL THEN STALL THIS WEEKEND NORTH OF THE GREAT LAKES, WHICH WILL
KEEP COOL SHOWERY CONDITIONS ACROSS THE UPPER OHIO VALLEY INTO
MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
MODIFIED POPS SLIGHTLY TO ACCOUNT FOR GREATER PRECIP COVERAGE AND BLENDED
IN LAMP TEMPS FOR 6-12 HOUR TREND. NEWEST HRRR FINALLY GETTING HANDLE
ON CONVECTIVE LINE BUT A LITTLE FASTER THAN WRF-NAM AND HIGH RES
MODEL WITH DEVELOPMENT IN WESTERN PA ALREADY BY 17-18Z.
PREVIOUS DISCUSSION FOLLOWS...
UPDATE USING BLEND OF RECENT RADAR AND SURFACE DATA COUPLED WITH
WRF-NMM AND SREF MODEL OUTPUT, HAVE MADE MAINLY SMALL ADJUSTMENTS
TO TIMING OF SHOWER BANDS. THE INITIAL PREFRONTAL BAND OF SHOWERS
AND ISOLATED THUNDERSTORMS WILL MAINLY AFFECT AREAS WEST OF THE
I-79 CORRIDOR.
THE NEXT BAND OF SHOWERS WILL BE ASSOCIATED WITH THE COLD FRONTAL
PASSAGE THIS AFTERNOON. WITH MORE RECENT MODELS SHOWING A SLIGHTLY
LATER PASSAGE TIME, THERE IS POTENTIAL FOR MORE INSTABILITY THAN
EARLIER ASSESSED AND HENCE MORE SEVERE POTENTIAL, AS SREF MODEL
PROFILES SHOW SUFFICIENT VERTICAL WIND SHEAR. HENCE HAVE INCLUDED
MENTION OF GUSTY WINDS WITH THUNDERSTORMS THIS AFTERNOON.
THIS CONCURS WITH SPC OUTLOOK OF A SLIGHT RISK OF SEVERE
THUNDERSTORMS FOR THE UPPER OHIO VALLEY AS FAR WEST AS THE I-77
CORRIDOR IN EASTERN OHIO. LIKEWISE CONCUR WITH SPC THAT THE MAIN
HAZARD WILL BE WIND RATHER THAN HAIL.
HAVE CONTINUED TO FORECAST TEMPERATURES SLIGHTLY COOLER THAN
NORMAL BASED ON RECENT GFS LAMP AND MOS OUTPUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
CONSENSUS OF SREF MODEL OUTPUT CONTINUES TO SHOW THE LOW PRESSURE
CENTER STALLING OVER CENTRAL ONTARIO PROVINCE SATURDAY BEFORE
SLOWLY EXITING EAST THROUGH NEW YORK STATE LATE SUNDAY. THIS
SCENARIO WILL CAUSE COOL SHOWERY CONDITIONS ACROSS THE UPPER OHIO
VALLEY THIS WEEKEND.
ACCORDINGLY, TEMPERATURES UNDER THIS PATTERN CAN BE 5 TO 10 DEGREES
BELOW NORMAL THROUGH THE WEEKEND, AS INDICATED BY BLEND OF GFS AND
NAM MOS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
CONDITIONS WILL REMAIN UNSETTLED AS A CLOSED UPPER LOW SLOWLY SHIFTS
EASTWARD OFF THE NEW ENGLAND COAST. ISOLATED TO SCATTERED SHOWERS
WILL PERSIST FOR THE FIRST PART OF NEXT WEEK IN NORTHWEST FLOW ALOFT.
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY DRY CONDITIONS FOR
WEDNESDAY AND THURSDAY.
TEMPERATURES UNDER THE EXITING NORTHEASTERN CONUS TROF ARE FORECAST
ABOUT 5 DEGREES UNDER THE SEASONAL AVERAGES USING A ECMWF AND GFS
GUIDANCE BLEND.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
VIGOROUS SYSTEM DEVELOPING IN THE UPPER ATMOSPHERE TODAY AS STRONG
JET WRAPS UNDERNEATH UPPER AIR LOW VICINITY SOUTHERN WISCONSIN.
SYSTEM GOES NEGATIVE AND SURFACE LOW DEEPENS AND PUSHES FROM KY
INTO UPPER GREAT LAKES. THIS WILL LIFT WARM FRONT NORTHWARD
FOLLOWED BY COLD FRONT THIS EVENING.IN ADVANCE OF FRONT...LINE OF
SHOWERS AND THUNDERSTORMS EXPECTED TO DEVELOP AND PUSH ACROSS
FORECAST AREA.
CURRENTLY...SHOWERS MOVING NORTHWARD FROM LOWER OHIO VALLEY AND
HAVE TIMED THEM INTO CWA 08-10Z. NEW HIGH-RES MODEL BRINGS
CONVECTIVE LINE THROUGH JUST A LITTLE LATER THAN PREVIOUS RUNS.
HAVE TIMED CONVECTIVE LINE WITH POSSIBLE SEVERE BETWEEN ABOUT 18Z TO
00Z WITH BEST TIME 19-23Z TIME FRAME ACROSS TERMINALS.
EAST TO SOUTHEAST WINDS INCREASE 8-11 KTS THIS MORNING FOLLOWED BY
INCREASE IN SOUTH TO SOUTHWEST 12-14G24KT THIS AFTERNOON.
TONIGHT BEHIND FRONT...WINDS SOUTHWEST 10-12KTS WITH CONTINUED
OVERCAST 020 NORTH TO 030 SOUTH AND POSSIBLY SOME SCATTERED -SHRA.
.OUTLOOK...SATURDAY THROUGH TUESDAY...
CLOSED UPPER LOW WILL MEANDER SLOWLY EASTWARD ACROSS THE GREAT
LAKES THIS WEEKEND AND OFF THE NEW ENGLAND COAST EARLY NEXT WEEK.
OCCASIONAL RESTRICTIONS CAN BE EXPECTED IN SHOWERS THROUGH
TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BILLINGS MT
932 AM MDT FRI JUN 1 2012
.SHORT TERM...VALID FOR TDY AND SAT...
THE SHOWERS THAT HAVE OCCURRED THIS MORNING FROM AROUND LIVINGSTON
TO SHERIDAN APPEAR TIED TO SOME WEAK 700-HPA FRONTOGENESIS IN WHAT
IS A RELATIVELY MOIST AIR MASS WITH PRECIPITABLE WATER VALUES NEAR
0.80 INCHES. THE 12 UTC NAM AND 06 UTC GFS BOTH CALL FOR THAT 700-
HPA THERMAL BOUNDARY TO LIFT NORTHEAST TODAY AS HEIGHTS RISE ALOFT
WITH WARM AIR ADVECTION INTO SOUTH CENTRAL MT. HOWEVER...THE MODEL
SIMULATIONS ALSO WEAKEN WHAT FRONTOGENETICAL FORCING DOES EXIST AS
IT MOVES NORTHEAST...WHICH MAY ADMITTEDLY NOT BE A BAD NOTION WITH
SHOWERS DIMINISHING SINCE ABOUT 14 UTC. FOR THAT REASON...WE CHOSE
TO LEAVE A DRY FORECAST IN TACT FOR SOUTHEASTERN MT THIS AFTERNOON
EVEN AS THE 700-HPA FRONT MOVES INTO THAT AREA. THE 12 UTC HRRR IS
THE ONLY MODEL TO GENERATE SCATTERED PRECIPITATION IN THAT AREA IN
THE 18 TO 00 UTC TIME FRAME...WHICH WAS NOT ENOUGH FOR US TO ALTER
THE POP FORECAST AT THIS TIME...EVEN THOUGH IT WILL BEAR WATCHING.
SOME POPS WILL BE IN PLACE THIS AFTERNOON ACROSS THE MOUNTAINS AND
NEARBY FOOTHILLS IN RESPECT TO SOME MODEST INSTABILITY AS THE MID-
LEVEL LAPSE RATES STEEPEN A BIT IN NORTHWEST FLOW ALOFT. WHILE THE
HEIGHTS ALOFT WILL ALSO BE RISING...THERE IS ENOUGH CONSENSUS WITH
MODEL SOLUTIONS TO INCLUDE 20 TO 30 POPS FOR THUNDERSTORMS ACROSS
THOSE AREAS. SCHULTZ
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
JET ENERGY WILL PULL THE GULF OF AK UPPER LOW...SEEN ON WATER VAPOR
IMAGERY EARLY THIS MORNING...INTO THE REGION NEXT WEEK. THERE WAS
SOME UNCERTAINTY AS TO HOW THE SYSTEM WILL PLAY OUT.
WEAK UPPER RIDGING OVER THE AREA ON SUN WILL AMPLIFY SUN NIGHT.
THERE WILL BE SOME LINGERING CONVERGENCE OVER THE AREA FROM AN
EARLIER FRONTAL PASSAGE ON SUN...BRING A CHANCE OF AFTERNOON
THUNDERSTORMS FROM KBIL TO KSHR W. THE LINGERING BOUNDARY AND A
PACIFIC MOISTURE FETCH WILL KEEP THE POSSIBILITY OF SHOWERS AND
THUNDERSTORMS OVER THE AREA SUN NIGHT. HEIGHTS WILL BUILD ON MON AS
THE TROUGH AMPLIFIES ALONG THE PACIFIC COAST. MID LEVEL WARMING WILL
CREATE CONVECTIVE INHIBITION IN THE AFTERNOON OVER AREAS E AND S OF
KBIL. HOWEVER...THIS INHIBITION WILL BE LESS OVER FAR SE MT WHERE
THE GFS HAD 1000 TO 2000 J/KG OF CAPE. CONFINED MORNING POPS TO W
AND N OF KBIL THEN LOWERED AFTERNOON POPS JUST SLIGHTLY. DUE TO THE
LARGE CAPES AND SOME SHEAR...ANY AFTERNOON AND EVENING THUNDERSTORMS
COULD BE STRONG TO SEVERE. S FLOW ALOFT WILL GRADUALLY PUSH E INTO
THE AREA MON NIGHT. A SURFACE LOW WILL PROVIDE LOW-LEVEL
CONVERGENCE...BUT MODELS ALL AGREED ON A WELL-PRONOUNCED DRY SLOT
PUSHING N THROUGH THE AREA. GIVEN THE LARGE AMOUNT OF CAPE OVER THE
AREA...CANNOT RULE OUT CONVECTION AND THE INHERITED SLIGHT CHANCE TO
CHANCE POPS LOOKED REASONABLE.
WILL HAVE JET DIVERGENCE FROM THE RIGHT-REAR QUADRANT OF A JET IN
THE EASTERN SIDE OF THE TROUGH TUE AFTERNOON AND EVENING. UPPER LOW
WILL PUSH E TOWARD THE AREA TUE AND TUE NIGHT. THE GFS WAS FURTHER N
WITH THE SYSTEM THAN THE ECMWF AND GEM...AND THERE WAS MUCH
UNCERTAINTY WITH THE PATH OF THE LOW ON WED. THE DRY SLOT WILL PUSH
E WITH TIME THROUGH TUE NIGHT. LOWERED POPS ON TUE DUE TO THE DRIER
AIR AND WENT WITH CHANCE POPS TUE NIGHT AS MOISTURE BEGINS TO
INCREASE OVER THE AREA. AGAIN CONDITIONS WOULD FAVOR SEVERE
THUNDERSTORMS ON TUE IN ANY CONVECTION. BLENDED WED POPS WITH THE
CONSALL DUE TO THE UNCERTAIN SYSTEM PATH. WENT WITH BELOW
CLIMATOLOGICAL POPS FOR THE REMAINDER OF THE PERIOD AS ANY SYSTEMS
APPEARED TO BE WEAK.
DID RAISE TEMPERATURES DURING THE POSSIBLE DRY SLOT NEXT WEEK. ARTHUR
&&
.AVIATION...
WIDELY SCATTERED SHOWERS WILL CONTINUE SOUTH OF A LINE FROM KLVM
TO KSHR THIS MORNING. THESE AREAS MAY BE ACCOMPANIED BY LOCALIZED
MVFR CONDITIONS. A WEAK DISTURBANCE WILL BRING A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING WEST OF A
KBIL TO KSHR LINE. SOME LOCALIZED AREAS OF MVFR CONDITIONS WILL
BE POSSIBLE. PRECIPITATION WILL BE ENDING LATE THIS EVENING AND
VFR CONDITIONS WILL PREVAIL. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 077 055/086 054/080 057/089 058/086 048/070 049/070
2/W 13/T 42/T 23/T 32/T 32/T 22/T
LVM 075 049/082 047/080 049/084 048/082 041/066 039/067
2/T 25/T 43/T 33/T 32/T 43/T 22/T
HDN 078 051/089 052/081 055/092 056/088 049/073 049/072
2/W 12/T 41/B 22/T 22/T 22/T 22/T
MLS 078 054/088 056/080 059/093 061/089 053/075 053/073
1/B 12/T 51/B 22/T 32/T 33/T 22/T
4BQ 076 051/088 054/079 056/092 060/088 052/075 050/072
1/B 02/T 21/B 22/T 22/T 22/T 32/T
BHK 075 052/085 056/077 057/088 060/084 054/075 051/073
1/B 12/T 41/B 22/T 32/T 33/T 32/T
SHR 073 048/085 050/081 054/088 058/086 046/073 046/069
3/W 12/T 32/T 22/T 21/B 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1030 AM EDT FRI JUN 1 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THE WEST TODAY AND CROSS THE
REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS ON
SATURDAY AND LINGER OVERHEAD ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...
SEVERE THUNDERSTORMS APPEAR LIKELY FOR MUCH OF CENTRAL NC THIS
AFTERNOON AND THIS EVENING.
CURRENT FORECAST IS GENERALLY ON TRACK THIS MORNING...AS A SHORTWAVE
TROUGH CURRENTLY APPROACHING THE OH AND TN VALLEYS WILL INTERACT
WITH A MOIST AND INCREASINGLY UNSTABLE WARM SECTOR AIRMASS EAST OF
THE APPALACHIANS. THE MAIN CONCERN FOR NEAR TERM UPDATES WILL BE
FOR HEATING AND DESTABILIZATION POTENTIAL.
A FEW SHOWERS AND STORMS ALONG A DIFFUSE SURFACE TO 850MB WARM FRONT
CONTINUE TO MOVE OFF TO THE NORTHEAST THIS MORNING...WITH A PERIOD
LITTLE ACTIVITY EXPECTED FOR THE NEXT COUPLE OF HOURS. STRATUS IS
SCATTERING RATHER QUICKLY OVER CENTRAL NC...AND SKIES ARE NEARLY
CLEAR OVER CENTRAL AND EASTERN SC. 12Z RAOBS AT KGSO AND KMHX SHOW
A STRONG BUT EASILY BREAKABLE CAP ABOVE THE MOIST BOUNDARY
LAYER...SO RAP FORECASTS OF 1500-2000 J/KG OF SBCAPE SEEM
ATTAINABLE. MODIFIED FORECAST SOUNDINGS FROM THE RAP GIVE 1000-1500
J/KG OF MLCAPE OVER EASTERN NC. THE HRRR AND CAMS HAVE PERFORMED
POORLY WITH THE PRECIP THIS MORNING...SO CONFIDENCE IN THEIR
DEPICTION OF CONVECTIVE IGNITION THROUGH MID AFTERNOON IS LOW.
HOWEVER...THE CAP SHOULD BREAK BY NOON AND CLOUD STREETS ARE
BEGINNING TO SHOW UP OVER THE SANDHILLS IN VISIBLE SATELLITE
IMAGERY...SO SHOWERS AND STORMS MAY BEGIN TO POP UP BY 18Z. ONE LAST
COMPLICATING FACTOR IS CLOUD COVER OVER MUCH OF VA...WHICH COULD
LEAD TO A DIFFERENTIAL HEATING BOUNDARY NEAR THE NC/VA BORDER THIS
AFTERNOON. WE WILL INCREASE POPS OVER THE EASTERN CWA EARLY THIS
AFTERNOON...AND CONTINUE THE HIGHER 80-90 POPS FROM EAST TO WEST
THIS EVENING.
AS THE UPPER TROUGH BECOMES NEGATIVELY TILLED AND LIFTS ACROSS THE
REGION THIS AFTERNOON...0-6KM EFFECTIVE SHEAR FORECASTS SHOW 35-40KT
BETWEEN THE POLAR JET TO THE NORTH AND A WEAKER COMPONENT OF THE
SUBTROPICAL JET EXPECTED TO EMERGE OVER SOUTHEAST GA/SC THIS
AFTERNOON. SURFACE WINDS HAVE BEEN BACKED TO SOUTHEASTERLY IN THE
VICINITY OF THE WEAK WARM FRONT THIS MORNING...BUT ALL MODELS
INDICATED WINDS WILL VEER TO SOUTHERLY AS MIXING INCREASES THIS
MORNING. DEEP LAYER SHEAR VALUES WILL BE SUPPORTIVE OF DISCRETE
SUPERCELLS OUT AHEAD OF THE LINEAR FORCING AND EXPECTED QLCS THIS
EVENING. AS UPPER LEVEL DIVERGENCE AND HEIGHT FALLS INCREASE THIS
EVENING...THE LOW LEVEL JET IF FORECAST TO STRENGTHEN
35-40KT...ESPECIALLY NORTH...WHICH WILL HELP TO INCREASE LOW LEVEL
HODOGRAPH CURVATURE AND MAY SUPPORT AN ISOLATED TORNADO THREAT. THE
CURRENT SLIGHT RISK FROM SPC CONTINUES TO SHOW A 10 PERCENT TORNADO
RISK NORTH OF THE TRIANGLE AND ROCKY MOUNT.
CONCERNING THE POTENTIAL QLCS THIS EVENING...MODELS HAVE SLOWED THE
ARRIVAL OF THE SURFACE TROUGH AND COLD FRONT BY A FEW HOURS...THOUGH
MOST OF THE CAMS SUGGEST THE COLD POOL WILL HAVE NO PROBLEM
REDEVELOPING EAST OF THE MOUNTAINS AND SURGING ACROSS THE UNSTABLE
AIRMASS AREA AFTER 21Z. LARGE SCALE SHEAR PARAMETERS AND SIMULATED
UPDRAFT HELICITY VALUES SUGGEST EMBEDDED SUPERCELL STRUCTURE WILL BE
POSSIBLE WITHIN THE LINE.
WE WILL LEAVE FORECAST HIGHS AS THEY ARE SINCE THEY ARE ON THE
WARMER SIDE OF GUIDANCE AND WIDESPREAD CLOUD COVER MAY NOT BE AN
ISSUE.
TONIGHT...BAND OF CONVECTION CROSSES THEN PIEDMONT DURING THE
EVENING...AND THE COASTAL PLAIN LATE THIS EVENING-OVERNIGHT. FAVOR
SLIGHTLY WARMER NAM-WRF MOS GUIDANCE VERSUS THE COOLER GFS.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 255 AM FRIDAY...
SATURDAY AND SATURDAY NIGHT....TRANQUIL WEATHER REGIME ENSUES BEHIND
EXITING FRONTAL SYSTEM WITH SURFACE HIGH CENTERED TO OUR SW.
RESULTANT W-NW FLOW WILL ADVECT DRIER MORE STABLE AIR INTO CENTRAL
NC. EXPECT TO SEE A FEW PASSING CLOUDS SATURDAY INTO SATURDAY NIGHT
THOUGH BULK OF COLUMN TOO DRY TO SUPPORT PRECIP GENERATION. TEMPS
SLIGHTLY BELOW NORMAL FOR EARLY JUNE. MAX TEMPS 75-80. MIN TEMPS
MID-UPPER 50S WITH A LOWER 50S IN THE NORMALLY COOLER LOCALES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 235 AM FRIDAY...
MEDIUM RANGE MODELS CONTINUE TO BE IN GENERAL AGREEMENT ON SHOWING A
RATHER AMPLIFIED PATTERN ACROSS THE CONUS NEXT WEEK... WITH
MID/UPPER LEVEL PATTERN FEATURING TROUGHING NEAR THE WEST AND EAST
COAST... WITH A CENTRAL U.S. RIDGE. WITH THE EAST COAST MID/UPPER
LEVEL LOW EXPECTED TO BE CENTERED INVOF NEW ENGLAND/OFF THE
NORTHEAST U.S. COAST... CENTRAL NC WILL REMAIN IN CYCLONIC FLOW
ALOFT... AND SUSCEPTIBLE TO DISTURANCES ROTATING THROUGH THE
CYCLONIC FLOW ALOFT. GIVEN THESE FEATURES ARE VERY DIFFICULT TO TIME
THIS FAR OUT IN TIME... WILL GO WITH A SLIGHT CHANCE OF
SHOWERS/STORMS FROM MONDAY NIGHT ONWARD. HOWEVER... THE GFS
CONTINUES TO HINT AT THE BEST CHANCE FOR PRECIP WILL BE MONDAY NIGHT
INTO TUESDAY. THUS... WILL GO WITH THE HIGHEST SLIGHT CHANCE POP
THEN. GIVEN THIS SYNOPTIC PATTERN WILL GO WITH HIGH AND LOW TEMPS
NEAR NORMAL... WITH EVEN SOME PERIODS OF BELOW NORMAL TEMPS POSSIBLE
DEPENDING ON TIMING OF DISTURBANCES AND ASSOCIATED
SHOWERS/STORMS/CLOUD COVER.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 745 AM FRIDAY...
SCATTERED STRONG TO SEVERE THUNDERSTORMS PROBABLE LATE TODAY AND
THIS EVENING ACROSS CENTRAL NC.
WIDESPREAD STRATUS WITH CEILINGS IN THE LIFR/IFR CATEGORIES WILL,
LIFT INTO A SCATTERED-BROKEN CU FIELD BY MID DAY WITH BASES
3500-4500FT.
THE APPROACH OF A STRONG LOW PRESSURE SYSTEM WILL INCREASE SHOWER
AND T-STORM ACTIVITY LATE TODAY AND THIS EVENING WITH A GOOD
PROBABILITY OF A FEW SEVERE STORMS WITH DAMAGING WINDS...LARGE HAIL
AND ISOLATED TORNADOES. THE THREAT FOR NUMEROUS SHOWERS AND STORMS
WILL BE GREATEST IN THE TRIAD REGION BETWEEN 4 PM AND 9 PM...AND IN
THE KRDU/KFAY AND KRWI VICINITY BETWEEN 6 PM AND 11 PM. AHEAD OF THE
SHOWERS AND STORMS...EXPECT LOW END VFR CONDITIONS WITH BREEZY SLY
WINDS GUSTING BETWEEN 20-25KTS.
THE COLD FRONT RESPONSIBLE FOR THE POTENTIALLY ACTIVE WEATHER THIS
EVENING WILL CROSS CENTRAL NC LATE TONIGHT. DRIER MORE STABLE AIR
WILL OVERSPREAD THE REGION BY EARLY SATURDAY WITH VFR CONDITIONS
PROJECTED THROUGH THE WEEKEND.
A SERIES OF UPPER LEVEL DISTURBANCES MAY CAUSE VFR CEILINGS MONDAY
WITH A POTENTIAL FOR SUB-VFR CEILINGS MONDAY NIGHT INTO TUESDAY AS A
SURFACE BOUNDARY DRIFTS ACROSS THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1020 AM CDT FRI JUN 1 2012
.DISCUSSION.../ISSUED AT 1020 AM CDT/
SOUTHEAST MOVING SHORT WAVE IS STILL COMING THROUGH AND SHOULD
PRODUCE SHOWERS WITH A THUNDERSTORM OR TWO AS IT MOVES SOUTHEAST.
WITH A BETTER HANDLE ON DETAILS...AM CONCENTRATING THE SHOWERS MORE
NEAR THE MISSOURI RIVER AREA FOR THE AFTERNOON INTO THE START OF THE
EVENING...AND HAVE DECREASED CHANCES OF RAIN SOMEWHAT TO THE NORTH
THOUGH THERE WILL STILL AT LEAST BE SOME SCATTERED LIGHT SHOWERS.
TIMING OF SYSTEM ON EARLIER FORECAST STILL LOOKS GOOD WITH SHOWERS
MOVING MOSTLY OUR DURING THE EVENING. TEMPERATURES MAY NEED A LITTLE
ADJUSTMENT UP IN SOME PARTS OF THE AREA ESPECIALLY NORTH...WITH
LESSER RAIN THREAT AND LIKELY THINNER CLOUD COVER THAN EXPECTED.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
SCATTERED SHOWERS WITH POSSIBLY ISOLATED THUNDERSTORMS WILL MOVE
SOUTHEAST OVER THE AREA THROUGH 02/00Z AND DECREASE TO THE EAST
02/00Z-06Z. LOW LEVEL MOISTURE IS NOT TOO HIGH AND ANY LOWERING OF
CONDITIONS TO MVFR WILL LIKELY BE LOCAL AND BRIEF...AND MOSTLY NEAR
THE MISSOURI RIVER AREA INCLUDING KSUX. AFTER 02/06Z CURRENTLY
EXPECT VFR FOR THE AREA THROUGH 02/18Z. WILL CONTINUE TO EXPLORE THE
POSSIBILITY OF LOCAL FOG DEVELOPMENT FOR THE 02/08Z-14Z TIME FRAME
BUT NO GENERAL LOWERING OF VISIBILITIES IS CURRENTLY EXPECTED.
&&
.PREV DISCUSSION.../ISSUED AT 428 AM CDT/
SHARPENING SHORTWAVE HARD TO MISS THIS MORNING ACROSS
NORTHEASTERN MONTANA...AND THIS WAVE WILL TRANSECT THE CWA TODAY
AND THIS EVENING...LEADING TO A VERY GOOD CHANCE FOR
RAINFALL...GIVEN THE STRENGTH OF PV ADVECTION...COLLOCATED WITH A
STRONG BELT OF LOWER TO MID LEVEL THETA E ADVECTION. ONE BIG
CHANGE THIS MORNING WAS A LARGE INCREASE TO POPS INTO THE LIKELY
TO CATEGORICAL RANGE WITH SYSTEM. TIMING AGAIN A CONCERN...WITH
MANY EARLIER HRRR RUNS BEING FAIRLY FRANTIC TAKING PRECIP UP TO
THE I29 CORRIDOR BY NOON. LATEST COUPLE HAVE SLOWED UP A BIT...BUT
AGAIN AS WITH THE SYSTEM A COUPLE DAYS AGO...THE DIV Q FIELDS
SUGGEST THAT LEADING PRECIP COULD JUMP AHEAD SOMEWHAT QUICKER THAN
EXPECTED...AND DID PUSH UP INTRODUCTION OF HIGHER POPS A COUPLE
HOURS HEADING EASTWARD THROUGH THE DAY. PRECIP IN ADVANCE OF A
WEAK LEADING WAVE MOVING INTO WESTERN SD ALREADY GETTING FAIRLY
WELL ORGANIZED ACROSS THE WESTERN DAKOTAS. INSTABILITY IS REALLY
FAIRLY MINIMAL...300-500 J/KG THROUGH MAINLY THE WESTERN HALF OF
THE AREA...SO EXPECT THAT THUNDER COVERAGE WILL LIKELY END UP A
CATEGORY OR TWO BELOW THE RAINFALL...BUT WORTHY OF MENTION. NOT
EXPECTING THE DECENT DEEP SHEAR TO HAVE MUCH IMPACT ON
ORGANIZATION AND THEREFORE SEVERE POTENTIAL...WHICH IS VERY VERY
LOW THROUGH THE WEST. OVERALL...THE RAINFALL WILL AGAIN HAVE A
STRONG INFLUENCE ON THE TEMPERATURES TODAY...BOTH KEEPING HIGHS
SOMEWHAT LOWER...AND ALSO IN NONDIURNAL TRENDS.
WAVE ZIPS THROUGH DURING THE EVENING...OUTRUNNING THE BETTER
INSTABILITY AND SHOULD LEAD TO DECREASING COVERAGE TO PRECIPITATION
FAIRLY QUICKLY THIS EVENING AS IT SHIFTS THROUGH MINNESOTA AND IOWA.
WITH EXPECTATION OF CLOUDS HOLDING SOMEWHAT TOUGH FROM NW IA THROUGH
THE I29 CORRIDOR...HAVE KEPT LOWS UP A BIT FROM PREVIOUS.
SATURDAY WILL BE A PEACH OF A DAY WITH SURFACE RIDGE SETTLING ACROSS
THE AREA. SHOULD BE A GOOD DEAL OF SUNSHINE ONCE ANY LINGERING
CLOUDS MIX OUT ALONG I29...AND TEMPERATURES WILL RESPOND MIXING TO
THE MID 70S EAST TO LOWER 80S WEST. HOWEVER...TEMPS REMAIN SOMEWHAT
CHILLY ALOFT...AND 50-70 J/KG MLCAPE DEVELOPS IN THE EAST ON
SATURDAY MIDDAY THROUGH MUCH OF AFTERNOON...BUT WITH THE LARGER
SCALE FAIRLY HOSTILE TO LIFT WITH DEEP SUBSIDENCE FORCING...KEPT
ISOLATED LEVEL POPS CLEAR OF THE FORECAST AND SETTLED ON INCREASING
THE SKYCOVER WITH EXPECTED CUMULUS FIELD DEVELOPING AHEAD OF LOW
LEVEL RIDGE AXIS.
ANOTHER WEAK WAVE WILL CROSS THE REGION...MAINLY TO THE NORTH ON
LATER SATURDAY NIGHT INTO SUNDAY. LOW LEVEL JET WILL STRENGTHEN
MODESTLY...AND WITH ADVERTISED CONVERGENCE POINT ALONG WITH THE
ADVANCE OF ELEVATED MIXED LAYER...COULD GET SOME ROGUE CONVECTION
LATER AT NIGHT THROUGH SD CWA...MAINLY NORTH.
SUNDAY IS STILL A BIT OF A QUANDARY...WITH SOLUTIONS RANGING FROM A
LARGE MCS ACROSS SW MN TO EXTREME WARMTH. SHOULD BE WARMER...
ESPECIALLY WEST AS BUILDING RIDGE ALLOWS WARMER AIRMASS TO SPREAD
EASTWARD. HOWEVER...SOME QUESTION AS TO IMPACT FROM EARLY DAY
CONVECTION TO TEMPS NORTH/EAST...AND WAS SOMEWHAT MORE CONSERVATIVE
IN HEATING FOR THESE LOCATIONS. TEMPERATURES WARM ENOUGH ALOFT THAT
EXPECT THAT FRONTAL BOUNDARY SHOULD REMAIN LARGELY CAPPED TOWARD THE
SOUTHWEST END...BUT AREAS FARTHER NORTHEAST/EAST MAY SEE SOME
RESURGENCE IN DEVELOPMENT HEADING THROUGH THE LATE AFTERNOON AND
EVENING. POPS REFLECT THE LOWER EXPECTATIONS WESTWARD ALONG
BOUNDARY...WHILE MAINTAINING CHANCE LEVELS TO THE EAST. IF
THUNDERSTORM WERE TO GET GOING LATE AFTERNOON AND EVENING...DEEP
LAYER SHEAR WOULD PROVE MARGINAL FOR SOME MINOR SEVERE THREAT.
DURING THE EXTENDED RANGE /MONDAY THROUGH THURSDAY/ EXPECTATIONS ARE
THAT AMPLIFYING BLOCKING RIDGE WILL MORE OR LESS PROTECT THE AREA
FROM PRECIPITATION THREAT. SOME ROGUE SOLUTIONS /NAMELY THE 00Z
ECMWF/ NOW ARE BACKING TROUGH THROUGH THE GREAT LAKES AND TAKING
ENERGY WESTWARD THROUGH RIDGE TO MELD WITH WESTERN TROUGH IN AN
ELONGATED EAST WEST AXIS...WHICH SEEMS HIGHLY UNLIKELY IN THE ARRAY
OF SOLUTIONS...PROBABLY AS MUCH AS THE GFS WITH PUSHY PIECE OF
WESTERN TROUGH MOVING THROUGH THE RIDGE WED/WED NIGHT. GENERALLY...
WITH SURFACE RIDGE NOSING IN FROM NORTH/NORTHEAST...WOULD BELIEVE
THAT SOME SLIGHTLY DRIER AIR WILL FILTER IN...AND WITH LIGHT WINDS
AT LEAST ON TUESDAY MORNING...SAW THIS AS OPPORTUNITY TO FAVOR MUCH
LOWER END OF GUIDANCE...CLOSER TO ENSEMBLE MEAN NUMBERS. HIGHS WILL
MAINLY START IN THE LOWER 80S FOR MOST...BUT SHOULD SEE A SLOW FALL
IN NUMBERS THROUGH MIDWEEK AS A RESULT OF POTENTIALLY GREATER AMOUNT
OF CLOUDS...BUT ALSO A SLOW COOLING OF THE OVERALL AIRMASS AS THE
MODIFIED POLAR AIRMASS SETTLES IN. DID KEEP SOME VERY SMALL POPS
BRUSHING THE FAR WEST OR SOUTHWEST TO ACCOUNT FOR MINIMAL RISK OF
CONVECTION ENCROACHING FROM THE HIGH PLAINS. /CHAPMAN
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 AM CDT FRI JUN 1 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
310 AM CDT FRI JUN 1 2012
MAIN FORECAST CHALLENGE IS ON SHOWER CHANCES BOTH THIS AFTERNOON AND
AGAIN SATURDAY AFTERNOON.
07Z WATER VAPOR IMAGERY SHOWING MID LEVEL LOW OVER SOUTHWEST
WISCONSIN...WHILE SURFACE ANALYSIS SHOWS LOW OVER THE OHIO VALLEY.
QUITE A FEW HIGH CLOUDS CONTINUE TO BE SEEN ACROSS THE FORECAST
AREA...BUT HAVE BEEN ON THE SLOW DECREASE THROUGHOUT THE NIGHT.
OVERALL...01.00Z MODELS OFFER SIMILAR SOLUTIONS THROUGH THE FORECAST
PERIOD. 500MB LOW LIFTS FROM SOUTHWEST WISCONSIN THIS MORNING INTO
SOUTHWEST LOWER MICHIGAN THIS AFTERNOON. COLD POOL ALOFT WILL RESULT
IN STEEP LOW LEVEL LAPSE RATES IN THE 1000MB-850MB LAYER WHERE THEY
WILL BE NEAR 9C/KM. ALTHOUGH CLOUDS WILL BE THIS THIS
MORNING...CUMULUS WILL DEVELOP BY MID TO LATE MORNING WITH A PARTLY
TO MOSTLY CLOUDY AFTERNOON IN STORE. WITH THESE LAPSE RATES AND MOST
UNSTABLE CAPES AROUND 200 J/KG COULD SEE SOME SHOWERS DEVELOP THIS
AFTERNOON. SIMILAR SCENARIO EXPECTED AGAIN SATURDAY AFTERNOON.
HOWEVER BY THIS TIME THE UPPER LOW WILL BE IN SOUTHERN ONTARIO AND
LAPSE RATES NOT QUITE AS STEEP AS TODAY...BUT STILL COULD SEE
SOME SHOWERS...ESPECIALLY OVER THE EASTERN AREAS. ALL OF THESE
SHOWERS WILL BE DIURNALLY DRIVEN AND WILL DISSIPATE BY EARLY EVENING
BOTH TODAY AND SATURDAY.
MID LEVEL TROUGH DROPS OVER THE RIDGE LOCATED OVER THE PLAINS ON
SUNDAY. MODELS SHOW SOME DIFFERENCES WITH THE TIMING AND DID
CONTINUE THE DRY FORECAST FOR THE DAY...WITH PRECIPITATION CHANCES
HOLDING OFF UNTIL SUNDAY NIGHT. GFS MOST ROBUST AND WOULD BRING
PRECIPITATION INTO THE AREA SUNDAY AFTERNOON...BUT SIDED WITH THE
SLOWER NAM/GEM SOLUTIONS AND PREVIOUS FORECAST.
.LONG TERM...MONDAY THROUGH THURSDAY
310 AM CDT FRI JUN 1 2012
BOTH THE 01.00Z ECMWF AND GFS SHOW TROUGHS ALONG BOTH COATS WITH
RIDGING ACROSS THE MIDDLE SECTION OF THE CONUS. DRY AND SEASONABLE
WEATHER EXPECTED THROUGH WEDNESDAY...WITH SOME MODEL DIFFERENCES
APPEARING LATER IN THE PERIOD WITH HOW STRONG THE RIDGE WILL BE AND
WILL IT BREAK DOWN ALLOWING FOR SYSTEMS TO TRACK ACROSS THE AREA.
THE ECMWF WOULD SUGGEST THIS TO BE THE CASE. DID KEEP LOWER END
PROBABILITIES FOR WEDNESDAY NIGHT AND THURSDAY.
&&
.AVIATION...
1100 AM CDT FRI JUN 1 2012
WEAK HIGH PRESSURE WILL INFLUENCE THE REGION THIS AFTERNOON...WITH
BUFKIT SOUNDINGS AND SATELLITE TRENDS SUPPORTING CU DEVELOPMENT. SEE
SOME POTENTIAL FOR SCT/ISOLD -SHRA. HRRR KEEPS THIS EAST OF THE TAF
SITES...CLOSE TO THE UPPER LEVEL LOW/SHORTWAVE ENERGY AND THE BETTER
MOISTURE. WILL KEEP ANY -SHRA OUT OF TAFS FOR NOW.
A BIT OF UPPER LEVEL ENERGY WILL SPIN SOUTHEAST ACROSS THE NORTHERN
PLAINS TONIGHT...ACROSS IA EARLY ON SAT. ANOTHER PIECE OF ENERGY IS
THEN EXPECTED TO DROP DOWN THE BACKSIDE OF THE DEPARTING UPPER LEVEL
TROUGH SAT AFTERNOON/EVENING. BOTH FEATURES COULD PRODUCE SOME
-SHRA. BELIEVE THE RAIN CHANCES SHOULD STAY WEST OF KRST
TONIGHT...WHILE SAT AFT/EVENING COULD BRING ISOLD -SHRA TO KLSE.
EXPECT SOME INCREASE IN HIGH CLOUDS LATER TODAY FROM THE NORTHERN
PLAINS SHORTWAVE. OVERALL...VFR CONDITIONS SHOULD PERSIST INTO SAT
NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CDT FRI JUN 1 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...JLR
LONG TERM....JLR
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
237 PM MDT FRI JUN 1 2012
.SHORT TERM...
(TONIGHT AND TOMORROW)
...SEVERE WEATHER LIKELY TOMORROW...
CURRENTLY...
A COOL FRONT HAS GONE THROUGH THE REGION. THIS BOUNDARY WAS JUST
SOUTH OF THE CWA AND WAS MOVING SLOWLY SOUTH. WINDS NORTH OF THE
BOUNDARY WERE ALREADY TURNING UPSLOPE WITH DEWPOINTS IN THE 40S.
THIS AFTERNOON AND EVENING...
AT THIS TIME...BEST CHANCE FOR STRONGER CONVECTION IS JUST SOUTH OF
THE CWA. THERE WILL STILL BE A CHANCE OF A STRONG STORM ACROSS FAR
SOUTHERN LAS ANIMAS COUNTY LATER TODAY (AS SHOWN BY LATEST
HRRR)...BUT THIS CONVECTION WILL QUICKLY MOVE SOUTH INTO NEW MEXICO.
AS FOR THE REST OF THE REGION...SIMULATIONS HAVE BACKED OFF A BIT ON
CONVECTION ALONG THE EAST FACING SLOPES OF THE S MTNS FOR THIS
AFTERNOON AND EVENING. HRRR IS RATHER DRY BUT THIS MAY BE A BIT
PESSIMISTIC AS I BELIEVE WE WILL SEE A FEW TSRA DEVELOP AND MOVE OFF
THE MTNS LATE THIS AFTERNOON AND EARLY EVENING. WHAT I HAVE DONE IS
KEPT POPS IN THE FCST...BUT HAVE DECREASED ALL OF VALUES INTO THE
ISOLATED CATEGORY.
LATER TONIGHT...
MOISTURE IS FCST TO INCREASE TONIGHT OVER THE PLAINS AS FLOW JUST
OFF THE SFC BECOMES SOUTHEASTERLY. THIS IS FCST TO BRING 45-50F
DEPOTS INTO A GOOD PART OF THE PLAINS BY SUNRISE TOMORROW. SOME LOW
CLOUDS WILL BE POSSIBLE ACROSS THE FAR SE PLAINS.
TOMORROW...
A CLASSIC "DAY 2" SEVERE WEATHER SETUP IS LIKELY TOMORROW. ALL
MODELS SHOW BETWEEN 2000 AND 3000 J/KG OF CAPE IMPINGING INTO FAR SE
CO BY 21Z TOMORROW. WINDS ALOFT ARE NOT ALL THAT STRONG BUT
SUFFICIENT DEEP SHEAR (AND PLENTY OF INSTABILITY) ALONG WITH 8 TO
9C/KM LAPSE RATES WILL BE IN PLACE OVER THE REGION. ALL MODELS ARE
PRINTING OUT CONVECTIVE QPF AND I HAVE NO REASON NOT TO BELIEVE THIS
OUTPUT. GIVEN THIS...WE WILL LIKELY SEE SOME ROTATING CONVECTION
TOMORROW. ALTHOUGH ALL OF THE PLAINS MAY SEE SVR WX TOMORROW...IT
APPEARS THE GREATEST POTENTIAL FOR SEVERE WEATHER WILL BE EAST AND
SOUTH OF A LINE FROM EADS...TO LAS ANIMAS TO KIM...AS THE STRONGEST
WINDS ALOFT AND BEST CAPE WILL BE IN THIS REGION. SPC DAY2 HAS THIS
AREA OUTLOOKED. THE MAIN THREATS WILL BE HAIL AND WIND...ALTHOUGH A
TORNADO CANNOT BE RULED OUT...ESPECIALLY OVER BACA COUNTY. GIVEN THE
W-NW FLOW ALOFT...ROTATING STORMS TOMORROW WILL MOVE SOUTHEAST TO
SOUTH-SOUTHEAST.
.LONG TERM...
(SATURDAY NIGHT THROUGH FRIDAY)
SATURDAY NIGHT...MODELS CONTINUE TO AGREE ON THUNDERSTORMS MOVING INTO
THE I-25 CORRIDOR AND EASTERN PLAINS SATURDAY NIGHT IN RESPONSE TO A
SHORTWAVE PASSING THROUGH NORTHERN COLORADO AND SOUTHEASTERLY FLOW
OVER THE EASTERN PLAINS. LATEST RUNS OF THE NAM/GFS/SREF ALL SHOW
0-6 KM BULK SHEARS OF 35-40 KTS...SBCAPE VALUES OF 1000-1500
J/KG...AND DEWPOINTS IN THE LOWER TO MID 50`S AT 00Z SUNDAY OVER THE
EASTERN PLAINS. THE GFS SHOWS THE MOST INSTABILITY WITH SBCAPE
VALUES OF OVER 2000 J/KG OVER THE EXTREME SOUTHEAST PLAINS...BUT
FEEL A MODEL CONSENSUS IS STILL THE APPROPRIATE SOLUTION IN THIS
CASE. SOME THUNDERSTORMS MAY BE SEVERE...ESPECIALLY CLOSE TO THE
KANSAS BORDER WHERE INSTABILITY WILL BE GREATEST.
SUNDAY-SUNDAY NIGHT...GFS/NAM CONTINUE TO SHOW WEAK WESTERLY FLOW
ALOFT ACROSS THE REGION AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE
REGION AHEAD OF AN UPPER TROUGH MOVING ONSHORE ACROSS THE WEST
COAST. BOTH MODELS SHOW CONVECTION FORMING OVER THE HIGHER TERRAIN
SUNDAY AFTERNOON. AROUND 00Z MONDAY...THE NAM SHOWS CONVECTION
FIRING ACROSS THE EASTERN PLAINS WHERE DEWPOINTS ARE FORECAST TO BE
IN THE MID 50S AND SBCAPES OVER 1500 J/KG. THE GFS...ON THE OTHER
HAND...SHOWS DEWPOINTS CLOSER TO 50...HALF AS MUCH CAPE...AND NO QPF
OVER THE EASTERN PLAINS. I FEEL THE NAM IS OVERDONE IN THIS
CASE...BUT STILL FEEL THUNDERSTORM DEVELOPMENT IS POSSIBLE GIVEN THE
RESIDUAL SURFACE MOISTURE AND TEMPERATURES IN THE LOW TO MID 90S. POPS
OVER THE HIGHER TERRAIN AND EASTERN PLAINS WERE RAISED IN THESE
AREAS.
MONDAY-FRIDAY...THE RIDGE AXIS WILL MOVE EAST OF THE COLORADO BY
TUESDAY AFTERNOON. MODELS INDICATE HIGH BASED/MOUNTAIN THUNDERSTORMS
WILL BE POSSIBLE BOTH MONDAY AND TUESDAY NIGHT BUT WEAK STEERING
FLOW SHOULD KEEP THEM MOSTLY OVER THE HIGHER TERRAIN. FAIRLY WEAK
SOUTHWESTERLY FLOW WILL THEN MOVE OVER THE REGION IN RESPONSE TO A
PACIFIC TROUGH DIGGING INTO THE NORTHWEST. MODELS DISAGREE WITH THE
PLACEMENT AND STRENGTH OF THE TROUGH. THE EC DIGS THE TROUGH DEEPER
INTO UTAH BY WEDNESDAY NIGHT AND THURSDAY. THE GFS IS FARTHER
NORTHWEST AND WEAKER WITH THE TROUGH DURING THAT TIME PERIOD.
THURSDAY AND FRIDAY THE FORECAST AREA WILL REMAIN UNDER WEAK
SOUTHWESTERLY FLOW AS THE AFOREMENTIONED TROUGH BEGINS TO LIFT INTO
WESTERN CANADA. TEMPERATURES LOOK AS IF THEY WILL REMAIN ABOVE
AVERAGE DURING THE ENTIRE EXTENDED PERIOD ACROSS THE FORECAST AREA.
-PJC
&&
.AVIATION...
MAIN CONCERN WILL BE TOMORROW AFTERNOON AS STRONGER CONVECTION WILL
BE POSSIBLE DURING THE EARLY TO MID AFTERNOON TIME PERIODS AT KCOS
AND KPUB. ATTM...PLAN TO MENTION VCTS IN THE TAFS AT THESE TWO SITES
AND LET LATER AVIATION FCSTS FINE TUNE THE THUNDER THREAT. THERE
WILL ALSO BE A VERY SLIGHT CHANCE OF SOME THUNDER AT KCOS AND KPUB
LATER THIS AFTERNOON...BUT THREAT TOO LOW TO EXPLICITLY MENTION IN
TAF (IF RADAR TRENDS CHANGE THIS AFTERNOON...THEN TAFS FCST WILL BE
ADJUSTED ACCORDINGLY). OTHERWISE...VFR CONDITIONS ARE EXPECTED AT
KCOS...KPUB AND KALS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
34/81
AREA FORECAST DISCUSSION
NWS DENVER CO
236 PM MDT FRI JUN 1 2012
.SHORT TERM...THE UPPER LEVEL RIDGE WILL SLOWLY SHIFT EAST ACROSS
THE GREAT BASIN TONIGHT AND SATURDAY. NORTHWEST FLOW TODAY WILL
BECOME MORE WESTERLY AS THE RIDGES NEARS. CAPES ARE UP TO 300 J/KG
OVER THE HIGHER TERRAIN. RADAR SHOWING SOME WEAK CONVECTION ALONG
THE FRONT RANGE...NOT SURE IF ANY RAIN IS REACHING THE GROUND YET.
THE HRRR SHOWS THIS WEAK CONVECTION CONTINUING THROUGH EARLY
EVENING. WILL HAVE LOW POPS THROUGH 04Z AND THEN NO MENTION OF
WEATHER UNTIL SATURDAY.
AIRMASS TO WARM A LITTLE MORE ON SATURDAY WITH MOST LOCATIONS OVER
NORTHEAST COLORADO WELL INTO THE 80S. MOISTURE WILL INCREASE SLIGHT
WITH DEW POINTS HANGING IN THE UPPER 30S TO 40S FOR MOST OF THE DAY.
CAPES WILL INCREASE TO 500-1000 J/KG SATURDAY. THIS COMBINED WITH A
SHORT WAVE TROUGH PASSING THROUGH THE RIDGE WILL PRODUCE ISOLATE TO
SCATTERED THUNDERSTORMS. THE BEST CHANCE WILL BE OVER THE EASTERN
PLAINS WHERE THE MOISTURE WILL BE GREATEST. WIND SHEAR WILL NOT BE
THAT GREAT...SO THE THREAT FOR SEVERE STORMS WILL BE LOW. THOUGH A
FEW MARGINALLY SEVERE STORMS CAN NOT BE RULED OUT.
&&
.LONG TERM...NO SIGNIFICANT CHANGES PLANNED. IT WILL BE WARMER
AND DRIER ON SUNDAY AND MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS
OVER THE WEST. ALTHOUGH TEMPERATURES WILL BE ABOVE NORMAL
...ELEVATING THE FIRE DANGER...THE WINDS AT THE SURFACE AND ALOFT
WILL BE WEAK WITH JUST A SLIGHT CHANCE OF THUNDERSTORMS IN THE
AFTERNOON AND EVENING. THE RIDGE AXIS WILL SHIFT OVER THE
SOUTHERN/CENTRAL PLAINS FOR TUESDAY AND WEDNESDAY WITH A WEAK
SOUTHERLY FLOW OVER COLORADO. THE SYNOPTIC PATTERN LOOKS LIKE A
MONSOON SETUP FOR A SHORT TIME BUT WITH LIMITED MOISTURE
AVAILABLE. THE MDLS SUGGEST SOME POTENTIAL FOR AFTN AND EVENING
THUNDERSTORMS WITH SFC DEWPOINTS IN THE MID 40S TO LOWER 50S OVER
THE NERN PLAINS OF COLORADO. ALL OF THIS ALREADY ADDRESSED IN THE
GRIDS SO NO ADJUSTMENTS AT THIS TIME. THE FLOW ALOFT MAY INCREASE
BY WEDNESDAY AS AN UPPER LEVEL TROUGH PASSES TO THE WEST AND NORTH
OF THE STATE ON WEDNESDAY SO MAYBE SOME MORE WIND BY MIDWEEK.
&&
.AVIATION...THERE WILL BE A SLIGHT CHANCE FOR A WEAK SHOWER OR
THUNDERSTORM THROUGH 03Z. MAIN THREAT WILL BE GUSTY OUTFLOW WINDS TO
30 KNOTS. OUTSIDE OF OUTFLOW WINDS...SURFACE WINDS WILL GENERALLY BE
OUT OF THE EAST THROUGH 03Z AND THEN SHIFT TO THE SOUTH BY 06Z. ON
SATURDAY...THERE WILL BE A BETTER CHANCE FOR AFTERNOON
THUNDERSTORMS.
&&
.HYDROLOGY...THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS THROUGH
EARLY EVENING. IF ANY STORMS FORM...THEY WILL BE SHORT LIVED AND
PRODUCE LIGHT RAINFALL. SCATTERED THUNDERSTORMS WILL BE POSSIBLE
SATURDAY. BRIEF HEAVY RAIN WILL BE POSSIBLE...BUT WITH STORM
MOVEMENTS AROUND 20-25 MPH...ANY HEAVY RAIN SHOULD BE SHORT IN
DURATION.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MEIER
LONG TERM....COOPER
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1251 PM EDT FRI JUN 1 2012
.AVIATION...18Z TAFS
IFR STRATUS AND AREAS OF DRIZZLE WILL CONTINUE FOR THE NEXT SEVERAL
HOURS WITHIN SHARP MID LVL TROUGH/DEFORMATION AXIS. A DRYING TREND
AND IMPROVING CIGS TO LOW MVFR CAN BE EXPECTED BY LATER THIS
AFTERNOON AS BACKING LOW LVL FLOW ALLOWS DRIER AIR TO ADVECT IN.
VFR CONDITIONS ARE EXPECTED BY LATER TONIGHT INTO SATURDAY AS
DEEPER MOISTURE AND LIFT SHIFTS NORTH INTO MICHIGAN.
&&
.PREV DISCUSSION... /ISSUED 355 AM EDT FRI JUN 1 2012/
SHORT TERM... /TODAY THROUGH SATURDAY NIGHT/
SFC LOW CONTINUES TO DEEPEN ACROSS SOUTHERN INDIANA EARLY THIS
MORNING IN RESPONSE TO STG TROUGH DIGGING THROUGH IOWA. BEST
ISENTROPIC LIFT HAS SHIFTED N INTO MICHIGAN...TAKING STEADIER PRECIP
WITH IT. MID LEVEL DRY SLOT HAS MADE IT INTO MUCH OF THE
AREA...KEEPING PRECIP MORE SCT IN NATURE. MOST LOCATIONS MISSED OUT
ON BEST RAINFALL...RECEIVING LESS THAN ONE QUARTER INCH. THE
EXCEPTION WAS NW OF KSBN TO THE LAKE WHERE BIT OF DEFORMATION ZONE
SETUP TO ALLOW FOR THREE QUARTERS TO OVER AN INCH OF RAIN FALL.
ADDITIONAL RAINFALL ACROSS THE NW WILL LIKELY BE UNDER A TENTH OF AN
INCH AS MAIN FOCUS FOR PRECIP SHIFTS SE TO HOPEFULLY GIVE PORTIONS
OF NW OHIO SOME MORE RAINFALL WITH LIMA OH ONLY SEEING A HUNDREDTH
OF AN INCH SO FAR. HRRR HAS HAD A DECENT HANDLE ON TRENDS WITH
ACTIVITY SLOWLY WINDING DOWN ACROSS NW 2/3RDS AND UPSWING IN PRECIP
AS SFC LOW MOVES INTO OHIO WITH BAND OF SHOWERS WORKING NW SOMEWHAT.
LAST HALF HOUR OR SO OF RADAR TRENDS SUGGEST THIS MAY BE UNDERWAY.
KEEPING FORECAST SIMPLE HAVE ONLY WENT WITH CHC SHOWER WORDING IN
ALL AREAS EXCEPT EAST QUARTER OR SO WHERE PRECIP LIKELY TO AFFECT
FOR AT LEAST THIS MORNING. EXTENSIVE CLOUD COVER WILL LIKELY KEEP
TEMPS PRETTY STEADY THIS MORNING AND POSSIBLE EVEN FALLING SOME AS
COLDER AIR WRAPS AROUND THE LOW AND WINDS INCREASE AS A RESULT OF
TIGHTENING PRESSURE GRADIENT ACROSS THE GREAT LAKES.
SPOKE OF ENERGY AND NW FLOW OFF THE LAKE WILL ALLOW FOR CLOUDS TO
CONTINUE ACROSS THE AREA THIS AFTERNOON WITH A FEW SHOWERS STILL
POSSIBLE ACROSS THE NORTH. BACKED OFF HIGHS A FEW DEGREES ESPECIALLY
NORTH WITH LITTLE OVERALL DIURNAL SWING EXPECTED.
OTHER THAN A FEW LIGHT SHOWERS OR LINGERING SPRINKLES...DRY
CONDITIONS SHOULD OVERSPREAD THE REGION WITH DECREASING CLOUDS.
UPPER LOW WILL MOVE NORTH OUT OF THE REGION SATURDAY. PIECE OF
ENERGY WILL MOVE THROUGH THE FLOW AND TRACK ACROSS LOWER GREAT LAKES
INTO THE OHIO VALLEY. FEATURE WILL BE MSTR STARVED BUT MAY BE
SUFFICIENT TO SPARK OFF A FEW LIGHT SHOWERS. WILL MAINTAIN CHC POPS
SATURDAY. TEMPS WILL WARM A GOOD 10 TO 15 DEGREES OR MORE ACROSS
MOST OF THE REGION DESPITE MOSTLY CLOUDY SKIES. LOWS SAT NGT WILL
DROP BACK INTO THE LOWER 50S UNDER CLEARING SKIES.
LONG TERM...
HIGH LAT BLOCK OVR THE NORTH ATL SPURNING STG NEG NAO WHICH WILL
CONT TO PERSIST THROUGH THIS PD RESULTING IN ANOMALOUS NRLY FLW ACRS
MUCH OF THE ERN US AND WHICH WILL PUSH ACTIVE POLAR JET SOUTH ACRS
THE GULF COAST. THUS XPC DRY AND SEASONABLY COOL WX TO PERSIST
THROUGH THE PD. OP GFS SOLUTION CONTS TO LOOK LIKE AN OUTLIER
SOLUTION SUN NIGHT/MON W/CONV FEEDBACK NOTED ALOFT. ALL OTHER MED
RANGE SOLUTIONS AT THAT RANGE ARE DRY YET AM FORCED TO HOLD ONTO 20S
FOR COLLABORATION.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...RIP CURRENT RISK THROUGH LATE TONIGHT FOR INZ003.
MI...RIP CURRENT RISK THROUGH LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR LMZ043-046.
&&
$$
SHORT TERM...FISHER
LONG TERM...T
AVIATION...STEINWEDEL
AREA FORECAST DISCUSSION
NWS WICHITA KS
1218 PM CDT FRI JUN 1 2012
.AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
SCATTERED ELEVATED CONVECTION WILL CONTINUE TO AFFECT MUCH OF THE
AREA THIS AFTERNOON...HOWEVER MAINLY VFR CONDITIONS EXPECTED TO
PREVAIL IN AND AROUND THE SHOWERS AND ISOLATED STORMS. THE WEAK
UPPER DISTURBANCE AND MID-LEVEL LIFT RESPONSIBLE FOR THE ACTIVITY
WILL MOVE SOUTH OF THE AREA DURING THE EVENING...WITH DRY WEATHER
EXPECTED FOR THE OVERNIGHT AND EARLY MORNING HOURS INTO SATURDAY.
KED
&&
.PREV DISCUSSION... /ISSUED 606 AM CDT FRI JUN 1 2012/
AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
LIFT/MOISTENING WITHIN NW-SE ORIENTED MID-LEVEL BAROCLINIC ZONE
SHOULD ALLOW SHOWERS TO SPREAD SOUTHEAST INTO CENTRAL/SOUTH
CENTRAL KS THIS MORNING...BEFORE SHIFTING ACROSS EASTERN KS THIS
AFTERNOON. LAPSE RATES/INSTABILITY APPEAR QUITE MARGINAL AND WILL
LEAVE THUNDER OUT OF TAFS FOR NOW. CEILINGS/VISIBILITIES EXPECTED
TO BE VFR. CLEARING FROM WEST TO EAST EXPECTED THIS EVENING.
JMC
PREV DISCUSSION... /ISSUED 326 AM CDT FRI JUN 1 2012/
DISCUSSION...
THE MAIN FORECAST CHALLENGES ARE THE MULTIPLE CHANCES FOR
PRECIPITATION THROUGH THE FORECAST.
SYNOPSIS:
THE MAIN UPPER LEVEL DISTURBANCE ACROSS THE CONUS IS MOVING EAST
OVER THE GREAT LAKES THIS MORNING LEAVING THE CENTRAL PLAINS UNDER
NORTHWEST FLOW. RIPPLES IN THE NORTHWEST FLOW HAVE HELPED TO
DEVELOP SCATTERED LIGHT SHOWERS ACROSS WESTERN KANSAS WHICH WILL
EVENTUALLY BE THE MAIN CONCERN FOR WEATHER TODAY. DESPITE THESE
LIGHT SHOWERS OVER WESTERN KANSAS...EASTERN KANSAS IS UNDER MOSTLY
CLEAR SKIES THIS MORNING WITH SURFACE HIGH PRESSURE MOVING
OVERHEAD. WINDS ARE LIGHT AND VARIABLE AND TEMPERATURES ARE IN THE
40S ACROSS THE AREA.
TODAY - SUNDAY:
A RIPPLE IN THE NORTHWESTERLY FLOW IS AND WILL CONTINUE TO BE THE
FOCUS FOR PRECIPITATION DEVELOPMENT TODAY. THE NAM/GFS/HRRR ALL
CONTINUE TO SHOW SHOWER AND THUNDERSTORM DEVELOPMENT THROUGHOUT THE
DAY TODAY. THE HRRR SEEMS TO HAVE A DECENT HANDLE OF CURRENT
TRENDS...AND THAT GIVES CONFIDENCE TO ITS SOLUTION...DEVELOPING
PRECIPITATION ACROSS CENTRAL KANSAS LATER THIS MORNING. THESE
SHOWERS AND THUNDERSTORMS WILL MOVE EASTWARD ACROSS THE STATE TODAY.
THE OVERCAST SKIES AND RAIN WILL HELP KEEP TEMPERATURES DOWN AND
HAVE DECREASED HIGH TEMPS SLIGHTLY TO ACCOUNT FOR THIS. TEMPS WILL
BE ABOUT 10-15 DEGREES BELOW NORMAL FOR EARLY JUNE.
SATURDAY SHOULD REMAIN DRY AND WARMER IN THE WAKE OF THE SYSTEM
TODAY...BUT PRECIPITATION CHANCES WILL RETURN EARLY SUNDAY MORNING
AS A DISTURBANCE UNDERCUTS THE UPPER LEVEL RIDGE AND APPROACHES THE
STATE. HAVE KEPT PRECIPITATION CHANCES THROUGH SUNDAY AND KNOCKED
MAX TEMPS DOWN SLIGHTLY WITH THE CLOUD COVER AND RAIN CHANCES.
MONDAY - THURSDAY:
UPPER LEVEL RIDGING WILL BUILD IN FOR THE FIRST WEEK IN JUNE. THE
MEDIUM RANGE GUIDANCE IS SOMEWHAT SIMILAR WITH THE EXTENDED
FORECAST...BUT THEY ARE CURRENTLY SHOWING SMALL DISTURBANCES
UNDERCUTTING THE RIDGE AND BRINGING CHANCES FOR PRECIP. WITH THE
NORTHWEST FLOW AND THESE DISTURBANCES CANNOT RULE OUT THE CHANCES
FOR PRECIPITATION...BUT CONFIDENCE ON TIMING AND COVERAGE IS LOW.
HAVE MAINTAINED MODEL CONSENSUS THROUGH THE EXTENDED FOR NOW. THE
BEST CHANCE FOR WIDESPREAD PRECIP DOES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY...BUT WILL NEED TO WATCH THIS AS THE FORECAST
EVOLVES. TEMPERATURES WILL GENERALLY WARM INTO THE UPPER 80S AND
LOW 90S THROUGH THE EXTENDED FORECAST.
BILLINGS
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 67 54 83 65 / 70 20 10 20
HUTCHINSON 67 53 83 64 / 70 10 10 20
NEWTON 65 52 82 64 / 70 10 10 20
ELDORADO 65 52 81 63 / 70 20 10 20
WINFIELD-KWLD 68 55 82 65 / 70 30 10 30
RUSSELL 69 53 83 64 / 70 10 10 20
GREAT BEND 70 53 84 63 / 60 10 10 20
SALINA 66 51 83 63 / 70 10 0 20
MCPHERSON 66 52 83 64 / 70 10 10 20
COFFEYVILLE 69 53 81 63 / 40 20 10 20
CHANUTE 67 52 81 62 / 30 10 10 10
IOLA 67 51 81 62 / 30 10 0 10
PARSONS-KPPF 68 52 81 63 / 40 20 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
700 PM EDT FRI JUN 1 2012
.SYNOPSIS...
AN UNSEASONABLY STRONG UPPER TROUGH AND ASSOCIATED COLD FRONT
WILL BRING A FEW SEVERE THUNDERSTORMS TO THE EASTERN CAROLINAS
THIS AFTERNOON AND OVERNIGHT. DRIER AND SLIGHTLY COOLER AIR WILL
OVERSPREAD THE REGION SATURDAY AND SUNDAY FOLLOWING THE COLD
FRONT. ANOTHER COLD FRONT WILL CROSS THE AREA TUESDAY MORNING.
AN UPPER TROUGH LINGERING ALONG THE EASTERN SEABOARD COULD BRING
ISOLATED TO SCATTERED THUNDERSTORMS MUCH OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 630 PM FRIDAY...CONVECTION HAS BECOME BETTER ORGANIZED
ACROSS THE SOUTHERN CWA OVER THE LAST HOUR. THIS CONVECTION WILL
BE MOVING INTO A MODERATELY UNSTABLE AIRMASS WITH SURFACE-BASED
CAPE OF 2000-2500 J/KG AND WILL BE ENHANCED BY SYNOPTIC ASCENT
PROVIDED BY THE APPROACH OF THE UPPER TROUGH. THEREFORE THE
SEVERE THREAT WILL CONTINUE FOR THE NEXT FEW HOURS...ESPECIALLY
ACROSS THE SOUTH CAROLINA COASTAL COUNTIES. A SECOND LINE OF
CONVECTION WILL MOVE ACROSS THE CWA AHEAD OF THE ACTUAL COLD FRONT
AND EXPECT IT TO PUSH OFF THE COAST AROUND 06Z. A LESS UNSTABLE
AIRMASS SHOULD LIMIT THE SEVERE THREAT FOR THIS SECONDARY LINE OF
STORMS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 330 PM FRIDAY...TREMENDOUSLY DIFFERENT FEEL TO THE WEATHER
THIS WEEKEND AS AN UNSEASONABLY ROBUST COLD FRONT MOVES OFFSHORE
FOLLOWED BY COOL AIR ADVECTION AND DRIER AIR INTO THE REGION.
THIS WILL RESULT IN A PCPN-FREE WEEKEND AND AN ALMOST "CRISP" FEEL
TO THE AIR SUNDAY MORNING WITH LOWS IN THE MID AND UPPER 50S AND
AROUND 60 AT THE COAST. MAX TEMPS TO RUN BELOW NORMAL WITH SUNDAY
MILDEST.
TIDAL CALCULATIONS INDICATE WE MAY NEED A COASTAL FLOOD ADVISORY
MAINLY FOR NUISANCE FLOODING DURING HIGH TIDES OVER THE WEEKEND.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 330 PM FRIDAY...PERSISTENT UPPER TROUGHINESS REMAINS IN PLACE
OVER THE NORTHEASTERN U.S. AND MIDATLANTIC THROUGH THE PERIOD. THIS
WILL ALLOW PIECES OF SHORTWAVE ENERGY TO MOVE THROUGH AT JUST ABOUT
ANY TIME BUT THESE FEATURES WILL BE TOO MOISTURE-DEPRIVED TO YIELD
ANY APPRECIABLE PRECIP CHANCES. THE STRONGEST OF THESE UPPER WAVES
MOVES THROUGH LATE TUESDAY OR TUESDAY NIGHT (OR MONDAY NIGHT
ACCORDING TO ECMWF) AND MAY BE STRONG ENOUGH TO HAVE A SURFACE
REFLECTION ALONG THE WEAK FRONTAL BOUNDARY IT DRIVES THROUGH THE
CAROLINAS. THIS EVENT WILL BRING THE BEST CHANCE FOR RAIN DURING THE
LONG TERM BUT CHANCES WILL NOT BE VERY HIGH AND THE CONTINUED
RELATIVE DRYNESS WILL MINIMIZE QPF WHERE PRECIP DOES MANAGE TO
OCCUR. TEMPERATURE DEVIATIONS FROM CLIMO WILL TEND TO BE SMALL...A
FEW DEGREES SHY BY DAY FROM WEAK CAA AND LOW HEIGHTS...A FEW DEGREES
ABOVE AT NIGHT DUE TO CLOUD COVER.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 23Z...FIRST BAND OF CONVECTION IS NOW EAST OF THE INLAND
TERMINALS...AND WILL LIKELY DISSIPATE BEFORE REACHING THE COAST.
BASED ON THE HRRR MODEL...ANOTHER ROUND OF CONVECTION IS EXPECTED TO
MOVE INTO THE WESTERN TERMINALS FROM 00-03Z. THIS CONVECTION HAS
SOME DYNAMICS TO SUPPORT IT...BUT THE LOSS OF SOLAR INSOLATION
SHOULD KEEP THE INTENSITY DOWN...WITH MVFR CONDITIONS EXPECTED WORST
CASE. OVERNIGHT...COLD FRONT WILL SWEEP THROUGH THE REGION FROM WEST
TO EAST WITH A WIND SHIFT TO THE NORTHWEST AND THE CESSATION OF ANY
PRECIP. SOME LIGHT SHOWERS COULD MAKE IT TO THE COAST...BUT WENT
WITH VCSH. SATURDAY...A NICE AVIATION DAY IN STORE WITH VFR
CONDITIONS AND A LIGHT NORTHWEST FLOW CONTINUING.
EXTENDED OUTLOOK...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
THROUGH SATURDAY. VFR EXPECTED FRIDAY THROUGH THE END OF THE PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 330 PM FRIDAY...WINDS AND SEAS REMAIN ON THE WEAK SIDE AT THIS
HOUR. STILL EXPECT WINDS TO INCREASE TO A RANGE OF 15-20 KNOTS LATER
WITH THE APPROACH/PASSAGE OF THE COLD FRONT. EXPECT THE STRONGEST
WINDS BETWEEN 0300 AND 0600 UTC. WILL MAINTAIN THE SHORT DURATION
SMALL CRAFT ADVISORY FOR THIS EVENING AND SCEC HEADLINE. BY MORNING
EXPECT A WESTERLY FLOW OF 10-15 KNOTS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 PM FRIDAY...WINDS AND SEAS WILL BE JUST STARTING TO
IMPROVE DAYBREAK SATURDAY...BUT STILL ROUGH...WITH LEFT OVER
SOUTHERLY SWELL ENERGY. THUS AN EXERCISE CAUTION STATEMENT MAY BE
NEEDED EARLY. AS THE WEEKEND PROGRESSES FURTHER IMPROVEMENT IS
EXPECTED. NW WINDS SATURDAY WILL BACK TO W-WSW BY SUNDAY...SPEEDS
GENERALLY 15 KT OR LESS.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 PM FRIDAY...WESTERLY WINDS EXPECTED THROUGH MOST OF THE
LONG TERM...ALTHOUGH SOME UNCERTAINTY EXISTS REGARDING TIMING OF A
FRONTAL BOUNDARY EXPECTED AROUND THE MID WEEK PERIOD. THIS
BOUNDARY MAY COME AS SOON AS MONDAY NIGHT AND ONLY BRING A SMALL
SHIFT FROM SW TO NW WITH ITS PASSAGE. OTHER SOLUTIONS ARE MUCH
SLOWER...AS LATE AS TUESDAY INTO TUESDAY NIGHT. THIS SOLUTION HAS
A STRONGER WAVE OF LOW PRESSURE THAT MAY INTRODUCE A PRECEDENT
SOUTHERLY WIND AND A STRONGER NW WIND IN ITS WAKE. THE PERSISTENCE
OF THE GFS MODEL SHOWING THIS SOLUTION MAKES IT FAIRLY APPEALING
AND THE FORECAST WILL BE NUDGED TOWARDS IT WITHOUT EMBRACING FULLY
IN CASE THE FASTER AND WEAKER SOLUTION PANS OUT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR AMZ250-252.
&&
$$
NEAR TERM...SHK/CRM
SHORT TERM...MJC
LONG TERM...MBB
AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
350 PM EDT FRI JUN 1 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THIS AFTERNOON AND CROSS THE
REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS ON
SATURDAY AND LINGER OVERHEAD ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 350 PM FRIDAY...
...A TORNADO WATCH IS IN EFFECT THROUGH 9 PM THIS EVENING FOR 5
COUNTIES NEIGHBORING THE VIRGINIA STATE LINE IN THE NORTHERN
PIEDMONT/COASTAL COUNTIES...
...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE REMAINDER OF
CENTRAL NC THROUGH 10 PM THIS EVENING...
CURRENT FORECAST IS GENERALLY ON TRACK THIS MORNING...AS A SHORTWAVE
TROUGH CURRENTLY APPROACHING THE OH AND TN VALLEYS WILL INTERACT
WITH A MOIST AND INCREASINGLY UNSTABLE WARM SECTOR AIRMASS EAST OF
THE APPALACHIANS. THE MAIN CONCERN FOR NEAR TERM UPDATES WILL BE
FOR HEATING AND DESTABILIZATION POTENTIAL.
A FEW SHOWERS AND STORMS ALONG A DIFFUSE SURFACE TO 850MB WARM FRONT
CONTINUE TO MOVE OFF TO THE NORTHEAST THIS MORNING...WITH A PERIOD
LITTLE ACTIVITY EXPECTED FOR THE NEXT COUPLE OF HOURS. STRATUS IS
SCATTERING RATHER QUICKLY OVER CENTRAL NC...AND SKIES ARE NEARLY
CLEAR OVER CENTRAL AND EASTERN SC. 12Z RAOBS AT KGSO AND KMHX SHOW
A STRONG BUT EASILY BREAKABLE CAP ABOVE THE MOIST BOUNDARY
LAYER...SO RAP FORECASTS OF 1500-2000 J/KG OF SBCAPE SEEM
ATTAINABLE. MODIFIED FORECAST SOUNDINGS FROM THE RAP GIVE 1000-1500
J/KG OF MLCAPE OVER EASTERN NC. THE HRRR AND CAMS HAVE PERFORMED
POORLY WITH THE PRECIP THIS MORNING...SO CONFIDENCE IN THEIR
DEPICTION OF CONVECTIVE IGNITION THROUGH MID AFTERNOON IS LOW.
HOWEVER...THE CAP SHOULD BREAK BY NOON AND CLOUD STREETS ARE
BEGINNING TO SHOW UP OVER THE SANDHILLS IN VISIBLE SATELLITE
IMAGERY...SO SHOWERS AND STORMS MAY BEGIN TO POP UP BY 18Z. ONE LAST
COMPLICATING FACTOR IS CLOUD COVER OVER MUCH OF VA...WHICH COULD
LEAD TO A DIFFERENTIAL HEATING BOUNDARY NEAR THE NC/VA BORDER THIS
AFTERNOON. WE WILL INCREASE POPS OVER THE EASTERN CWA EARLY THIS
AFTERNOON...AND CONTINUE THE HIGHER 80-90 POPS FROM EAST TO WEST
THIS EVENING.
AS THE UPPER TROUGH BECOMES NEGATIVELY TILLED AND LIFTS ACROSS THE
REGION THIS AFTERNOON...0-6KM EFFECTIVE SHEAR FORECASTS SHOW 35-40KT
BETWEEN THE POLAR JET TO THE NORTH AND A WEAKER COMPONENT OF THE
SUBTROPICAL JET EXPECTED TO EMERGE OVER SOUTHEAST GA/SC THIS
AFTERNOON. SURFACE WINDS HAVE BEEN BACKED TO SOUTHEASTERLY IN THE
VICINITY OF THE WEAK WARM FRONT THIS MORNING...BUT ALL MODELS
INDICATED WINDS WILL VEER TO SOUTHERLY AS MIXING INCREASES THIS
MORNING. DEEP LAYER SHEAR VALUES WILL BE SUPPORTIVE OF DISCRETE
SUPERCELLS OUT AHEAD OF THE LINEAR FORCING AND EXPECTED QLCS THIS
EVENING. AS UPPER LEVEL DIVERGENCE AND HEIGHT FALLS INCREASE THIS
EVENING...THE LOW LEVEL JET IF FORECAST TO STRENGTHEN
35-40KT...ESPECIALLY NORTH...WHICH WILL HELP TO INCREASE LOW LEVEL
HODOGRAPH CURVATURE AND MAY SUPPORT AN ISOLATED TORNADO THREAT. THE
CURRENT SLIGHT RISK FROM SPC CONTINUES TO SHOW A 10 PERCENT TORNADO
RISK NORTH OF THE TRIANGLE AND ROCKY MOUNT.
CONCERNING THE POTENTIAL QLCS THIS EVENING...MODELS HAVE SLOWED THE
ARRIVAL OF THE SURFACE TROUGH AND COLD FRONT BY A FEW HOURS...THOUGH
MOST OF THE CAMS SUGGEST THE COLD POOL WILL HAVE NO PROBLEM
REDEVELOPING EAST OF THE MOUNTAINS AND SURGING ACROSS THE UNSTABLE
AIRMASS AREA AFTER 21Z. LARGE SCALE SHEAR PARAMETERS AND SIMULATED
UPDRAFT HELICITY VALUES SUGGEST EMBEDDED SUPERCELL STRUCTURE WILL BE
POSSIBLE WITHIN THE LINE.
WE WILL LEAVE FORECAST HIGHS AS THEY ARE SINCE THEY ARE ON THE
WARMER SIDE OF GUIDANCE AND WIDESPREAD CLOUD COVER MAY NOT BE AN
ISSUE.
TONIGHT...BAND OF CONVECTION CROSSES THEN PIEDMONT DURING THE
EVENING...AND THE COASTAL PLAIN LATE THIS EVENING-OVERNIGHT. FAVOR
SLIGHTLY WARMER NAM-WRF MOS GUIDANCE VERSUS THE COOLER GFS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 350 PM FRIDAY...
A LARGE CLOSED UPPER LOW WILL DRIFT NORTHWARD TOWARD THE UPPER GREAT
LAKES ON SATURDAY. BY DAYBREAK...THE ATTENDANT SURFACE COLD FRONT
WILL HAVE LONG EXITED THE AREA...WITH WEAK SURFACE HIGH OVER THE
LOWER MS VALLEY WORKING ITS WAY EASTWARD INTO THE CAROLINAS. DRIER
NOTICEABLY LESS HUMID AIR WILL FILTER WEST TO EAST INTO CENTRAL
NC...WITH ANY LINGERING MOISTURE IN THE EAST SATURDAY MORNING GIVING
WAY TO INCREASING SUNSHINE THROUGH THE AFTERNOON. MORNING THICKNESSES
START OUT 30 METERS BELOW NORMAL...AND REBOUND TO 20 METERS SHY OF
TODAYS AFTERNOON THICKNESSES...SUPPORTING HIGHS IN THE MID 70S TO
AROUND 80.
WILL LIKELY SEE A RESURGENCE OF MID/HIGH CLOUDS LATE SATURDAY
AFTERNOON THROUGH SATURDAY NIGHT WITH A RESURGENCE OF 30-40 METER H5
HEIGHT FALLS AND DCVA AS ADDITIONAL S/W ENERGY SWINGS THROUGH THE
AREA...RESULTING IN OCCASIONAL PARTLY TO MOSTLY CLOUDY SKIES
SATURDAY NIGHT...ESPECIALLY ACROSS THE NORTH. OVERNIGHT LOWS IN THE
MID TO UPPER 50S.
SYNOPTIC SCALE SCALE SUBSIDENCE IN THE WAKE AFOREMENTIONED SHORTWAVE
WILL BE IN PLACE SUNDAY AND SUNDAY NIGHT...RESULTING IN CONTINUED
DRY CONDITIONS. AIRMASS WILL CONTINUE TO MODERATE AS SURFACE
ANTICYCLONE SHIFTS SOUTHWARD OVER THE GULF COAST REGION. A 15 METER
THICKNESS INCREASE WILL SUPPORT A RETURN OF DAYTIME HIGHS IN THE
LOWER TO MID 80S WITH A SLOWER RETURN OF HUMIDITY. OVERNIGHT LOWS
SUNDAY NIGHT IN THE UPPER 50S TO LOWER 60S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM FRIDAY...
THE ATMOSPHERIC BLOCKING PATTERN OVER THE LOWER 48 STATES IN
ASSOCIATION WITH A STRONGLY NEGATIVE PHASE OF THE NAO WILL RESULT IN
A SLOW PROGRESSION OF THE GENERAL WEATHER PATTERN...WITH THE EASTERN
US REMAINING UNDER THE INFLUENCE OF THE CUT-OFF LOW OVER SOUTHERN
NEW ENGLAND.
WHILE THERE ARE SOME TIMING DIFFERENCES...MEDIUM RANGE MODELS ARE
DEPICTING A PROMINENT MID-UPPER LEVEL SHORTWAVE TROUGH DIVING
SOUTHEAST THROUGH THE MID-ATLANTIC REGION IN THE LATE MONDAY-LATE
TUESDAY TIME PERIOD...WITH ATTENDANT SURFACE WAVE/LOW ACCOMPANYING
THE UPPER WAVE PASSAGE. AT THIS TIME...IT APPEARS THAT THIS SYSTEM
WILL BE THE NEXT SIGNIFICANT WEATHER SYSTEM FOR CENTRAL
NC...BRINGING THE NEXT CHANCE FOR WIDESPREAD CONVECTION/RAIN CHANCES
DURING THE LONG TERM PERIOD. OTHERWISE...THE FORECAST WILL BE MARRED
BY NORTHWEST FLOW DISTURANCES SWINGING THROUGH THE BASE OF THE LONG
WAVE TROUGH THAT ARE UNRESOLVABLE WITH ANY RELIABILITY THIS FAR OUT.
WILL CARRY A CHANCE POPS FOR MONDAY EVENING THROUGH TUESDAY NIGHT
AND THEN DRY AFTERWARD.
EXPECT SEASONABLE TEMPERATURES UNDERNEATH THE EASTERN US TROUGH WITH
DAYTIME HIGHS IN THE 79 TO 84. LOWS IN THE LOWER TO MID 60S.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 115 PM FRIDAY...
SCATTERED STRONG TO SEVERE THUNDERSTORMS PROBABLE LATE TODAY AND
THIS EVENING ACROSS CENTRAL NC.
CEILINGS ARE LIFTING TO THE 2500-3500FT RANGE THIS AFTERNOON AND
CLOUD COVER IS VARIABLE...SO PERIODS OF HIGH MVFR CONDITIONS WILL
CONTINUE TO BE POSSIBLE. A STRONG STORMS SYSTEM IS APPROACHING THE
REGION TODAY...AND SCATTERED SHOWERS AND STORMS THAT HAVE POPPED UP
SINCE 16Z NORTHEAST OF KRDU....AND WILL BECOME MORE NUMEROUS OVER
THE WESTERN PIEDMONT BY 19-21Z. WE EXPECT STORMS MOVING INTO THE
KCLT AREA AND WESTERN PIEDMONT WILL MERGE INTO A LINE OF STORMS AND
CROSS CENTRAL NC BETWEEN 19-02Z. STRONG WINDS IN EXCESS OF 50-60MPH
WILL BE POSSIBLE IN THE STRONGEST PARTS OF THE LINE...WITH IFR AND
LIFR CONDITIONS. WE WILL ATTEMPT TO TIME THE MOST PROBABLY TIME
PERIOD OF STORMS WITH VCTS...WITH THE MOST ADVERSE AVIATION
CONDITIONS LIKELY FOR AN HOUR OR LESS DURING THE TIME PERIOD.
A COLD FRONT WILL CROSS THE AREA LATER THIS EVENING...AND MAY BRING
ANOTHER ROUND OF SHOWERS AND STORMS...ALTHOUGH INSTABILITY MAY BE
LIMITED IF THE FIRST ROUND OF STORMS IS WIDESPREAD.
NONETHELESS...ADVERSE AVIATION CONDITIONS WILL BE POSSIBLE WITH
CONVECTION ALONG OR JUST AHEAD OF THE FRONT. CONDITIONS WILL
IMPROVE BEHIND THE FRONT AFTER MIDNIGHT.
A SERIES OF UPPER LEVEL DISTURBANCES MAY CAUSE VFR CEILINGS MONDAY
WITH A POTENTIAL FOR SUB-VFR CEILINGS MONDAY NIGHT INTO TUESDAY AS A
SURFACE BOUNDARY DRIFTS ACROSS THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...SMITH
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...WSS/SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
226 PM EDT FRI JUN 1 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THIS AFTERNOON AND CROSS THE
REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS ON
SATURDAY AND LINGER OVERHEAD ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 226 PM FRIDAY...
...A TORNADO WATCH IS IN EFFECT THROUGH 9 PM THIS EVENING FOR 5
COUNTIES NEIGHBORING THE VIRGINIA STATE LINE IN THE NORTHERN
PIEDMONT/COASTAL COUNTIES...
...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE REMAINDER OF
CENTRAL NC THROUGH 10 PM THIS EVENING...
CURRENT FORECAST IS GENERALLY ON TRACK THIS MORNING...AS A SHORTWAVE
TROUGH CURRENTLY APPROACHING THE OH AND TN VALLEYS WILL INTERACT
WITH A MOIST AND INCREASINGLY UNSTABLE WARM SECTOR AIRMASS EAST OF
THE APPALACHIANS. THE MAIN CONCERN FOR NEAR TERM UPDATES WILL BE
FOR HEATING AND DESTABILIZATION POTENTIAL.
A FEW SHOWERS AND STORMS ALONG A DIFFUSE SURFACE TO 850MB WARM FRONT
CONTINUE TO MOVE OFF TO THE NORTHEAST THIS MORNING...WITH A PERIOD
LITTLE ACTIVITY EXPECTED FOR THE NEXT COUPLE OF HOURS. STRATUS IS
SCATTERING RATHER QUICKLY OVER CENTRAL NC...AND SKIES ARE NEARLY
CLEAR OVER CENTRAL AND EASTERN SC. 12Z RAOBS AT KGSO AND KMHX SHOW
A STRONG BUT EASILY BREAKABLE CAP ABOVE THE MOIST BOUNDARY
LAYER...SO RAP FORECASTS OF 1500-2000 J/KG OF SBCAPE SEEM
ATTAINABLE. MODIFIED FORECAST SOUNDINGS FROM THE RAP GIVE 1000-1500
J/KG OF MLCAPE OVER EASTERN NC. THE HRRR AND CAMS HAVE PERFORMED
POORLY WITH THE PRECIP THIS MORNING...SO CONFIDENCE IN THEIR
DEPICTION OF CONVECTIVE IGNITION THROUGH MID AFTERNOON IS LOW.
HOWEVER...THE CAP SHOULD BREAK BY NOON AND CLOUD STREETS ARE
BEGINNING TO SHOW UP OVER THE SANDHILLS IN VISIBLE SATELLITE
IMAGERY...SO SHOWERS AND STORMS MAY BEGIN TO POP UP BY 18Z. ONE LAST
COMPLICATING FACTOR IS CLOUD COVER OVER MUCH OF VA...WHICH COULD
LEAD TO A DIFFERENTIAL HEATING BOUNDARY NEAR THE NC/VA BORDER THIS
AFTERNOON. WE WILL INCREASE POPS OVER THE EASTERN CWA EARLY THIS
AFTERNOON...AND CONTINUE THE HIGHER 80-90 POPS FROM EAST TO WEST
THIS EVENING.
AS THE UPPER TROUGH BECOMES NEGATIVELY TILLED AND LIFTS ACROSS THE
REGION THIS AFTERNOON...0-6KM EFFECTIVE SHEAR FORECASTS SHOW 35-40KT
BETWEEN THE POLAR JET TO THE NORTH AND A WEAKER COMPONENT OF THE
SUBTROPICAL JET EXPECTED TO EMERGE OVER SOUTHEAST GA/SC THIS
AFTERNOON. SURFACE WINDS HAVE BEEN BACKED TO SOUTHEASTERLY IN THE
VICINITY OF THE WEAK WARM FRONT THIS MORNING...BUT ALL MODELS
INDICATED WINDS WILL VEER TO SOUTHERLY AS MIXING INCREASES THIS
MORNING. DEEP LAYER SHEAR VALUES WILL BE SUPPORTIVE OF DISCRETE
SUPERCELLS OUT AHEAD OF THE LINEAR FORCING AND EXPECTED QLCS THIS
EVENING. AS UPPER LEVEL DIVERGENCE AND HEIGHT FALLS INCREASE THIS
EVENING...THE LOW LEVEL JET IF FORECAST TO STRENGTHEN
35-40KT...ESPECIALLY NORTH...WHICH WILL HELP TO INCREASE LOW LEVEL
HODOGRAPH CURVATURE AND MAY SUPPORT AN ISOLATED TORNADO THREAT. THE
CURRENT SLIGHT RISK FROM SPC CONTINUES TO SHOW A 10 PERCENT TORNADO
RISK NORTH OF THE TRIANGLE AND ROCKY MOUNT.
CONCERNING THE POTENTIAL QLCS THIS EVENING...MODELS HAVE SLOWED THE
ARRIVAL OF THE SURFACE TROUGH AND COLD FRONT BY A FEW HOURS...THOUGH
MOST OF THE CAMS SUGGEST THE COLD POOL WILL HAVE NO PROBLEM
REDEVELOPING EAST OF THE MOUNTAINS AND SURGING ACROSS THE UNSTABLE
AIRMASS AREA AFTER 21Z. LARGE SCALE SHEAR PARAMETERS AND SIMULATED
UPDRAFT HELICITY VALUES SUGGEST EMBEDDED SUPERCELL STRUCTURE WILL BE
POSSIBLE WITHIN THE LINE.
WE WILL LEAVE FORECAST HIGHS AS THEY ARE SINCE THEY ARE ON THE
WARMER SIDE OF GUIDANCE AND WIDESPREAD CLOUD COVER MAY NOT BE AN
ISSUE.
TONIGHT...BAND OF CONVECTION CROSSES THEN PIEDMONT DURING THE
EVENING...AND THE COASTAL PLAIN LATE THIS EVENING-OVERNIGHT. FAVOR
SLIGHTLY WARMER NAM-WRF MOS GUIDANCE VERSUS THE COOLER GFS.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 255 AM FRIDAY...
SATURDAY AND SATURDAY NIGHT....TRANQUIL WEATHER REGIME ENSUES BEHIND
EXITING FRONTAL SYSTEM WITH SURFACE HIGH CENTERED TO OUR SW.
RESULTANT W-NW FLOW WILL ADVECT DRIER MORE STABLE AIR INTO CENTRAL
NC. EXPECT TO SEE A FEW PASSING CLOUDS SATURDAY INTO SATURDAY NIGHT
THOUGH BULK OF COLUMN TOO DRY TO SUPPORT PRECIP GENERATION. TEMPS
SLIGHTLY BELOW NORMAL FOR EARLY JUNE. MAX TEMPS 75-80. MIN TEMPS
MID-UPPER 50S WITH A LOWER 50S IN THE NORMALLY COOLER LOCALES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 235 AM FRIDAY...
MEDIUM RANGE MODELS CONTINUE TO BE IN GENERAL AGREEMENT ON SHOWING A
RATHER AMPLIFIED PATTERN ACROSS THE CONUS NEXT WEEK... WITH
MID/UPPER LEVEL PATTERN FEATURING TROUGHING NEAR THE WEST AND EAST
COAST... WITH A CENTRAL U.S. RIDGE. WITH THE EAST COAST MID/UPPER
LEVEL LOW EXPECTED TO BE CENTERED INVOF NEW ENGLAND/OFF THE
NORTHEAST U.S. COAST... CENTRAL NC WILL REMAIN IN CYCLONIC FLOW
ALOFT... AND SUSCEPTIBLE TO DISTURANCES ROTATING THROUGH THE
CYCLONIC FLOW ALOFT. GIVEN THESE FEATURES ARE VERY DIFFICULT TO TIME
THIS FAR OUT IN TIME... WILL GO WITH A SLIGHT CHANCE OF
SHOWERS/STORMS FROM MONDAY NIGHT ONWARD. HOWEVER... THE GFS
CONTINUES TO HINT AT THE BEST CHANCE FOR PRECIP WILL BE MONDAY NIGHT
INTO TUESDAY. THUS... WILL GO WITH THE HIGHEST SLIGHT CHANCE POP
THEN. GIVEN THIS SYNOPTIC PATTERN WILL GO WITH HIGH AND LOW TEMPS
NEAR NORMAL... WITH EVEN SOME PERIODS OF BELOW NORMAL TEMPS POSSIBLE
DEPENDING ON TIMING OF DISTURBANCES AND ASSOCIATED
SHOWERS/STORMS/CLOUD COVER.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 115 PM FRIDAY...
SCATTERED STRONG TO SEVERE THUNDERSTORMS PROBABLE LATE TODAY AND
THIS EVENING ACROSS CENTRAL NC.
CEILINGS ARE LIFTING TO THE 2500-3500FT RANGE THIS AFTERNOON AND
CLOUD COVER IS VARIABLE...SO PERIODS OF HIGH MVFR CONDITIONS WILL
CONTINUE TO BE POSSIBLE. A STRONG STORMS SYSTEM IS APPROACHING THE
REGION TODAY...AND SCATTERED SHOWERS AND STORMS THAT HAVE POPPED UP
SINCE 16Z NORTHEAST OF KRDU....AND WILL BECOME MORE NUMEROUS OVER
THE WESTERN PIEDMONT BY 19-21Z. WE EXPECT STORMS MOVING INTO THE
KCLT AREA AND WESTERN PIEDMONT WILL MERGE INTO A LINE OF STORMS AND
CROSS CENTRAL NC BETWEEN 19-02Z. STRONG WINDS IN EXCESS OF 50-60MPH
WILL BE POSSIBLE IN THE STRONGEST PARTS OF THE LINE...WITH IFR AND
LIFR CONDITIONS. WE WILL ATTEMPT TO TIME THE MOST PROBABLY TIME
PERIOD OF STORMS WITH VCTS...WITH THE MOST ADVERSE AVIATION
CONDITIONS LIKELY FOR AN HOUR OR LESS DURING THE TIME PERIOD.
A COLD FRONT WILL CROSS THE AREA LATER THIS EVENING...AND MAY BRING
ANOTHER ROUND OF SHOWERS AND STORMS...ALTHOUGH INSTABILITY MAY BE
LIMITED IF THE FIRST ROUND OF STORMS IS WIDESPREAD.
NONETHELESS...ADVERSE AVIATION CONDITIONS WILL BE POSSIBLE WITH
CONVECTION ALONG OR JUST AHEAD OF THE FRONT. CONDITIONS WILL
IMPROVE BEHIND THE FRONT AFTER MIDNIGHT.
A SERIES OF UPPER LEVEL DISTURBANCES MAY CAUSE VFR CEILINGS MONDAY
WITH A POTENTIAL FOR SUB-VFR CEILINGS MONDAY NIGHT INTO TUESDAY AS A
SURFACE BOUNDARY DRIFTS ACROSS THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS/SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
115 PM EDT FRI JUN 1 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THIS AFTERNOON AND CROSS THE
REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS ON
SATURDAY AND LINGER OVERHEAD ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...
SEVERE THUNDERSTORMS APPEAR LIKELY FOR MUCH OF CENTRAL NC THIS
AFTERNOON AND THIS EVENING.
CURRENT FORECAST IS GENERALLY ON TRACK THIS MORNING...AS A SHORTWAVE
TROUGH CURRENTLY APPROACHING THE OH AND TN VALLEYS WILL INTERACT
WITH A MOIST AND INCREASINGLY UNSTABLE WARM SECTOR AIRMASS EAST OF
THE APPALACHIANS. THE MAIN CONCERN FOR NEAR TERM UPDATES WILL BE
FOR HEATING AND DESTABILIZATION POTENTIAL.
A FEW SHOWERS AND STORMS ALONG A DIFFUSE SURFACE TO 850MB WARM FRONT
CONTINUE TO MOVE OFF TO THE NORTHEAST THIS MORNING...WITH A PERIOD
LITTLE ACTIVITY EXPECTED FOR THE NEXT COUPLE OF HOURS. STRATUS IS
SCATTERING RATHER QUICKLY OVER CENTRAL NC...AND SKIES ARE NEARLY
CLEAR OVER CENTRAL AND EASTERN SC. 12Z RAOBS AT KGSO AND KMHX SHOW
A STRONG BUT EASILY BREAKABLE CAP ABOVE THE MOIST BOUNDARY
LAYER...SO RAP FORECASTS OF 1500-2000 J/KG OF SBCAPE SEEM
ATTAINABLE. MODIFIED FORECAST SOUNDINGS FROM THE RAP GIVE 1000-1500
J/KG OF MLCAPE OVER EASTERN NC. THE HRRR AND CAMS HAVE PERFORMED
POORLY WITH THE PRECIP THIS MORNING...SO CONFIDENCE IN THEIR
DEPICTION OF CONVECTIVE IGNITION THROUGH MID AFTERNOON IS LOW.
HOWEVER...THE CAP SHOULD BREAK BY NOON AND CLOUD STREETS ARE
BEGINNING TO SHOW UP OVER THE SANDHILLS IN VISIBLE SATELLITE
IMAGERY...SO SHOWERS AND STORMS MAY BEGIN TO POP UP BY 18Z. ONE LAST
COMPLICATING FACTOR IS CLOUD COVER OVER MUCH OF VA...WHICH COULD
LEAD TO A DIFFERENTIAL HEATING BOUNDARY NEAR THE NC/VA BORDER THIS
AFTERNOON. WE WILL INCREASE POPS OVER THE EASTERN CWA EARLY THIS
AFTERNOON...AND CONTINUE THE HIGHER 80-90 POPS FROM EAST TO WEST
THIS EVENING.
AS THE UPPER TROUGH BECOMES NEGATIVELY TILLED AND LIFTS ACROSS THE
REGION THIS AFTERNOON...0-6KM EFFECTIVE SHEAR FORECASTS SHOW 35-40KT
BETWEEN THE POLAR JET TO THE NORTH AND A WEAKER COMPONENT OF THE
SUBTROPICAL JET EXPECTED TO EMERGE OVER SOUTHEAST GA/SC THIS
AFTERNOON. SURFACE WINDS HAVE BEEN BACKED TO SOUTHEASTERLY IN THE
VICINITY OF THE WEAK WARM FRONT THIS MORNING...BUT ALL MODELS
INDICATED WINDS WILL VEER TO SOUTHERLY AS MIXING INCREASES THIS
MORNING. DEEP LAYER SHEAR VALUES WILL BE SUPPORTIVE OF DISCRETE
SUPERCELLS OUT AHEAD OF THE LINEAR FORCING AND EXPECTED QLCS THIS
EVENING. AS UPPER LEVEL DIVERGENCE AND HEIGHT FALLS INCREASE THIS
EVENING...THE LOW LEVEL JET IF FORECAST TO STRENGTHEN
35-40KT...ESPECIALLY NORTH...WHICH WILL HELP TO INCREASE LOW LEVEL
HODOGRAPH CURVATURE AND MAY SUPPORT AN ISOLATED TORNADO THREAT. THE
CURRENT SLIGHT RISK FROM SPC CONTINUES TO SHOW A 10 PERCENT TORNADO
RISK NORTH OF THE TRIANGLE AND ROCKY MOUNT.
CONCERNING THE POTENTIAL QLCS THIS EVENING...MODELS HAVE SLOWED THE
ARRIVAL OF THE SURFACE TROUGH AND COLD FRONT BY A FEW HOURS...THOUGH
MOST OF THE CAMS SUGGEST THE COLD POOL WILL HAVE NO PROBLEM
REDEVELOPING EAST OF THE MOUNTAINS AND SURGING ACROSS THE UNSTABLE
AIRMASS AREA AFTER 21Z. LARGE SCALE SHEAR PARAMETERS AND SIMULATED
UPDRAFT HELICITY VALUES SUGGEST EMBEDDED SUPERCELL STRUCTURE WILL BE
POSSIBLE WITHIN THE LINE.
WE WILL LEAVE FORECAST HIGHS AS THEY ARE SINCE THEY ARE ON THE
WARMER SIDE OF GUIDANCE AND WIDESPREAD CLOUD COVER MAY NOT BE AN
ISSUE.
TONIGHT...BAND OF CONVECTION CROSSES THEN PIEDMONT DURING THE
EVENING...AND THE COASTAL PLAIN LATE THIS EVENING-OVERNIGHT. FAVOR
SLIGHTLY WARMER NAM-WRF MOS GUIDANCE VERSUS THE COOLER GFS.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 255 AM FRIDAY...
SATURDAY AND SATURDAY NIGHT....TRANQUIL WEATHER REGIME ENSUES BEHIND
EXITING FRONTAL SYSTEM WITH SURFACE HIGH CENTERED TO OUR SW.
RESULTANT W-NW FLOW WILL ADVECT DRIER MORE STABLE AIR INTO CENTRAL
NC. EXPECT TO SEE A FEW PASSING CLOUDS SATURDAY INTO SATURDAY NIGHT
THOUGH BULK OF COLUMN TOO DRY TO SUPPORT PRECIP GENERATION. TEMPS
SLIGHTLY BELOW NORMAL FOR EARLY JUNE. MAX TEMPS 75-80. MIN TEMPS
MID-UPPER 50S WITH A LOWER 50S IN THE NORMALLY COOLER LOCALES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 235 AM FRIDAY...
MEDIUM RANGE MODELS CONTINUE TO BE IN GENERAL AGREEMENT ON SHOWING A
RATHER AMPLIFIED PATTERN ACROSS THE CONUS NEXT WEEK... WITH
MID/UPPER LEVEL PATTERN FEATURING TROUGHING NEAR THE WEST AND EAST
COAST... WITH A CENTRAL U.S. RIDGE. WITH THE EAST COAST MID/UPPER
LEVEL LOW EXPECTED TO BE CENTERED INVOF NEW ENGLAND/OFF THE
NORTHEAST U.S. COAST... CENTRAL NC WILL REMAIN IN CYCLONIC FLOW
ALOFT... AND SUSCEPTIBLE TO DISTURANCES ROTATING THROUGH THE
CYCLONIC FLOW ALOFT. GIVEN THESE FEATURES ARE VERY DIFFICULT TO TIME
THIS FAR OUT IN TIME... WILL GO WITH A SLIGHT CHANCE OF
SHOWERS/STORMS FROM MONDAY NIGHT ONWARD. HOWEVER... THE GFS
CONTINUES TO HINT AT THE BEST CHANCE FOR PRECIP WILL BE MONDAY NIGHT
INTO TUESDAY. THUS... WILL GO WITH THE HIGHEST SLIGHT CHANCE POP
THEN. GIVEN THIS SYNOPTIC PATTERN WILL GO WITH HIGH AND LOW TEMPS
NEAR NORMAL... WITH EVEN SOME PERIODS OF BELOW NORMAL TEMPS POSSIBLE
DEPENDING ON TIMING OF DISTURBANCES AND ASSOCIATED
SHOWERS/STORMS/CLOUD COVER.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 115 PM FRIDAY...
SCATTERED STRONG TO SEVERE THUNDERSTORMS PROBABLE LATE TODAY AND
THIS EVENING ACROSS CENTRAL NC.
CEILINGS ARE LIFTING TO THE 2500-3500FT RANGE THIS AFTERNOON AND
CLOUD COVER IS VARIABLE...SO PERIODS OF HIGH MVFR CONDITIONS WILL
CONTINUE TO BE POSSIBLE. A STRONG STORMS SYSTEM IS APPROACHING THE
REGION TODAY...AND SCATTERED SHOWERS AND STORMS THAT HAVE POPPED UP
SINCE 16Z NORTHEAST OF KRDU....AND WILL BECOME MORE NUMEROUS OVER
THE WESTERN PIEDMONT BY 19-21Z. WE EXPECT STORMS MOVING INTO THE
KCLT AREA AND WESTERN PIEDMONT WILL MERGE INTO A LINE OF STORMS AND
CROSS CENTRAL NC BETWEEN 19-02Z. STRONG WINDS IN EXCESS OF 50-60MPH
WILL BE POSSIBLE IN THE STRONGEST PARTS OF THE LINE...WITH IFR AND
LIFR CONDITIONS. WE WILL ATTEMPT TO TIME THE MOST PROBABLY TIME
PERIOD OF STORMS WITH VCTS...WITH THE MOST ADVERSE AVIATION
CONDITIONS LIKELY FOR AN HOUR OR LESS DURING THE TIME PERIOD.
A COLD FRONT WILL CROSS THE AREA LATER THIS EVENING...AND MAY BRING
ANOTHER ROUND OF SHOWERS AND STORMS...ALTHOUGH INSTABILITY MAY BE
LIMITED IF THE FIRST ROUND OF STORMS IS WIDESPREAD.
NONETHELESS...ADVERSE AVIATION CONDITIONS WILL BE POSSIBLE WITH
CONVECTION ALONG OR JUST AHEAD OF THE FRONT. CONDITIONS WILL
IMPROVE BEHIND THE FRONT AFTER MIDNIGHT.
A SERIES OF UPPER LEVEL DISTURBANCES MAY CAUSE VFR CEILINGS MONDAY
WITH A POTENTIAL FOR SUB-VFR CEILINGS MONDAY NIGHT INTO TUESDAY AS A
SURFACE BOUNDARY DRIFTS ACROSS THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS/SMITH
AREA FORECAST DISCUSSION
NWS SPOKANE WA
249 PM PDT Fri Jun 1 2012
.SYNOPSIS...
The weekend will get off to a wet start as a strong and moist
cold front will promote widespread showers and breezy
conditions. The latter half of the weekend will see drier
conditions. Temperatures will remain near or cooler than normal
for this time of year. A brief warm-up is expected on Monday ahead
of a strong cold front. This front will likely deliver some
thunderstorms on Monday into Monday evening. The remainder of the
week will see a progressive pattern with occasional showers and
cooler than normal temperatures.
&&
.DISCUSSION...
Tonight and Saturday...Satellite imagery this afternoon indicated
a cold front along 130W with models showing this front to move
rapidly eastward into the Inland Northwest overnight tonight into
Saturday morning. The front will cross the Cascades overnight into
Eastern Washington, reaching the Idaho Panhandle late tonight into
Saturday morning. Prior to the front passage a moist and somewhat
unstable air mass will result in scattered showers over northeast
Washington and the Idaho Panhandle as well as the East Slopes of
the Cascades. LAPS data from this afternoon indicated CAPES of
200-600 J/KG over the Blues, Northeast Washington Mountains and
Idaho Panhandle. However visible satellite trends and HRRR argue
for only a minimal thunder threat so opted to remove the
thunderstorm wording this evening.
Then as the cold front crosses the Cascades a right entrance
region of an upper jet will result in added lift such that bands
of showers will likely develop over North Central Washington with
this activity moving east during the night as the front and jet
move east. Meanwhile...the most intense showers are expected over
the Blues Mountains, Lewiston area, and Camas Prairie as an area of
elevated instability passes through. Could see isolated
thunderstorms in these areas overnight into Saturday morning.
Behind the front a pronounced dry slot will bring clearing from
west to east on Saturday. This will be especially pronounced in
the lee of the Cascades with a mostly sunny and breezy day
expected. Over the Northeast Washington Mountains and Idaho
Panhandle lingering instability in the afternoon will likely
trigger additional post frontal shower activity along with a
slight chance of thunderstorms. JW
Saturday night through Monday...Strong upper level low is expected to
remain parked over the Gulf of Alaska through the weekend.
Various disturbances will wrap around the eastern periphery of the
low...but the brunt of the energy will generally skirt the region.
Models are in good agreement that the first disturbance will drift
inside of 130w by 12z Sunday then continue northeast and weaken as
it heads across western Washington. Potential instability with
this system looks rather paltry while much of the moisture is
confined above 700 mbs. Suspect the main impact will be an
increasing cloud trend as well as a chance of light rain showers
or sprinkles...with the best chances occurring over the SE portion
of the forecast area. The models have been backing off of late on
the QPF amounts and if this continues...pops may need to be
lowered even further.
By late Sunday night and into Monday...the pattern becomes much more
interesting as the aforementioned Gulf of Alaska low drops south
and east...turning the mean flow to more of a southerly
orientation. The n-s oriented upper level jet is expected to
bisect Washington by late afternoon...with the eastern third of
Washington and the Idaho Panhandle under the strongly difluent
upper level flow. This flow will coincide with a rapid
destabilization the lower atmosphere warms in response to the low-
level southerly flow. By afternoon...CAPE values surge toward 1000
j/kg...with only weak CIN or convective caps expected. All that`s
needed to tap into this instability and overcome this CIN is a
trigger. None of the models are forecasting a shortwave trough to
get things going during the afternoon...as much of the upper level
energy will remain far south of the forecast area. Thus the main
trigger will have to come from orographic ascent. It`s always
difficult to tell if this ascent will be strong enough to overcome
the CIN...but if it does...thunderstorms could develop rapidly.
Any updrafts could become sustained as 0-6 km shear values look
fairly impressive. Based on model soundings...we cannot rule out
an isolated severe or large thunderstorm....however confidence
would be much higher provided a shortwave would aid in the
breaking of the CIN.
Temperatures will begin the period near seasonal normals...however the
Monday pattern will lead to a significant warm up over the eastern
half of the forecast area...with 70s and even a lower 80 possible.
fx
Monday night through Friday...Overall agreement between models
exists in advertising the arrival of a deep upper level
trough/closed low early in the period...a residence time over or
near the forecast area during the lion`s share of the upcoming
work week...and then the slow departure near the end of the week.
Individual models differ with detailed placement of the main
trough axis/closed low center...but no matter which model verifies
confidence is increasing for a cooler than normal and unsettled
forecast through most of next week. While there are no easily
identifiable organized storm systems within this flow regime...the
presence of wrap-around moisture providing fuel for instability
associated with cool air aloft will create a chance of showers
just about anywhere in the forecast area each day through Thursday
at least...with densest concentrations of showers over the high
terrain surrounding the basin and the eastern half of the Columbia
Basin. By Friday model consensus suggests an exit of the upper
level trough...which may provide the best bet for an essentially
dry day...although southwest flow in advance of the next offshore
trough may lead to a few showers on the higher terrain even on this
day. Once again...without drilling too much into the details given
sub-synoptic model differences...there is fairly high confidence
of a showery...cool and unsettled extended period. /Fugazzi
&&
.AVIATION...
18Z TAFS: Abundant low level moisture across Northeast Washington
and North Idaho will result in low cloud bases with MVFR conditions
at times through 19-21z with gradually rises CIGS in the afternoon.
The atmosphere will become unstable this afternoon with cumulus
buildups over Northeast Washington and North Idaho with sct -SHRA
and isolated TSRA expected north of the KGEG-KCOE corridor. This
activity will die off around 1-3z. Then a vigorous cold front will
cross the Cascades after 06z with increasing showers along and ahead
of the front especially at KPUW and KLWS. Mid level instability may
also trigger thunderstorms in this area mainly from 6-15z Saturday.
Increasing rain showers and low level upslope flow into KPUW should
result in MVFR conditions 11-16z. KLWS may also see MVFR conditions
per NAM model rh time height plots. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 54 70 47 67 48 69 / 60 60 10 10 20 60
Coeur d`Alene 53 69 46 65 49 72 / 60 70 10 10 30 60
Pullman 55 68 44 65 49 68 / 60 60 10 10 40 60
Lewiston 61 73 53 72 55 75 / 60 60 10 10 50 60
Colville 52 76 45 73 47 70 / 70 50 0 10 10 70
Sandpoint 53 68 42 65 44 71 / 60 80 10 20 20 70
Kellogg 52 66 44 64 47 73 / 60 90 10 30 40 60
Moses Lake 58 77 50 74 53 68 / 40 20 0 10 30 60
Wenatchee 57 75 54 72 55 65 / 30 10 0 0 20 50
Omak 53 76 47 72 47 67 / 50 10 0 10 10 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION...RETRANSMISSION
NWS LA CROSSE WI
247 PM CDT FRI JUN 1 2012
.SHORT TERM...TONIGHT THROUGH MONDAY
247 PM CDT FRI JUN 1 2012
FORECAST CHALLENGES MAINLY CENTERED AROUND SHOWER/ISOLATED THUNDER
CHANCES THROUGH THE PERIOD.
CURRENT WATER VAPOR AND RAP 500MB ANALYSIS SHOW A CLOSED LOW OVER
LAKE MICHIGAN WHILE A WEAK MID-LEVEL TROUGH WAS ROTATING SOUTHEAST
THROUGH ND. COLD POOL ALOFT ASSOCIATED WITH THE LAKE MICHIGAN LOW
WAS PRODUCING STEEP TEMPERATURES LAPSE RATES AND EXTENSIVE CUMULUS
FIELD ACROSS THE FORECAST AREA. RADAR QUIET AT THIS POINT WITH NO
SIGNIFICANT ECHOES/SHOWERS INDICATED. MEANWHILE...FORCING ASSOCIATED
WITH THE WAVE UPSTREAM OVER ND WAS PRODUCING SCATTERED SHOWERS/ISOLD
THUNDER ACROSS ACROSS EASTERN ND INTO EASTERN NEB. OTHERWISE...
TEMPERATURES ACROSS THE FORECAST AREA THIS AFTERNOON WERE IN THE MID
60S TO AROUND 70 DEGREES.
01.12Z NCEP MODELS AND 01.09Z SREF SHOWING GOOD AGREEMENT WITH
HANDLING OF SYNOPTIC PATTERN THROUGH SUNDAY. GFS A BIT DEEPER WITH
THE MID-LEVEL WAVE ROTATING ACROSS ACROSS THE AREA MONDAY FOR BETTER
SATURATION/RAINFALL POTENTIAL. GENERALLY WENT WITH A CONSENSUS BLEND
AS A RESULT.
FOR TONIGHT...WILL BE WATCHING THE WAVE OVER ND ROTATE SOUTHEAST
WHILE DAMPENING OUT SOME. THE WAVE IS EXPECTED TO SCOOT SOUTHEAST
INTO IA BY 12Z. MOST OF THE FORCING...IE PV-ADVECTION/ISENTROPIC
LIFT AND MOISTURE TRANSPORT AND RESULTANT -SHRA CHANCES EXPECTED TO
BE TIED VERY CLOSE TO THE WAVE ITSELF AND JUST SOUTHWEST OF THE
AREA. HI-RES MESO MODELS ALSO SHOWS ACTIVITY REMAINING MAINLY
SOUTHWEST OF THE AREA. MAINTAINED JUST A SLIGHT -SHRA CHANCE
BASICALLY SOUTHWEST OF A LINE FROM AUSTIN MN TO OELWEIN IA AFTER 03Z
UNTIL 12Z. REST OF THE AREA/BASICALLY EAST OF THE MISSISSIPPI RIVER
SHOULD SEE CLEARING SKIES. THE CLEARING SKIES AND VERY LIGHT
NORTHWEST WINDS ARE EXPECTED TO PRODUCE FAIRLY CHILLY TEMPERATURES
OVERNIGHT...MAINLY IN THE FAVORED COLD SPOT AREAS SUCH AS
SPARTA/BLACK RIVER FALLS. WILL LIKELY SEE TEMPERATURES DIP INTO THE
UPPER 30S IN THOSE AREAS. ELSEWHERE...EXPECT TEMPERATURES MAINLY IN
THE 40S.
FOR SATURDAY...CLOSED LOW WILL DEEPEN SOME OVER LAKE HURON.
ASSOCIATED COLD POOL/CYCLONIC FLOW ALOFT WILL RESIDE OVER THE AREA
WITH 0-3KM MUCAPE AROUND 800J/KM AND MLCAPE AROUND 500J/KG. THIS
SHOULD BE SUFFICIENT ENOUGH FOR SHRA CHANCES ALONG WITH ISOLD
THUNDER. NAM SHOWING ABOUT 15-16 PVU/S ADVECTING SOUTHEAST ACROSS
AREAS NORTHEAST OF I-94 FOR PERHAPS A BETTER SHOT AT THUNDER
ACTIVITY. OTHERWISE...WITH EXTENSIVE CUMULUS AND ISOLD/SCT SHRA
ACTIVITY...TEMPERATURES ARE EXPECTED TO REMAIN SLIGHTLY BELOW NORMAL
IN THE UPPER 60S TO LOWER 70S. A FEW SHOWERS EXPECTED TO LINGER INTO
EARLY SATURDAY EVENING MAINLY NORTHEAST OF I-94. LOOK FOR CLEARING
SKIES THEN THROUGH THE REMAINDER OF THE OVERNIGHT HOURS AS SURFACE
HIGH PRESSURE DRIFTS OVER THE REGION WITH LOWS FALLING INTO THE
MIDDLE 40S TO LOWER 50S.
LATEST MODELS ARE TRENDING A BIT FASTER/STRONGER WITH A MID-LEVEL
TROUGH MOVING SOUTHEAST OUT OF THE NORTHERN PLAINS ON SUNDAY.
AFFECTS OF THIS WAVE WILL BE INCREASING MID-LEVEL CLOUDS THROUGH THE
AFTERNOON WITH A CHANCE OF SHRA/ISOLD THUNDER. THIS WILL BE MANLY
NORTHWEST OF A LINE FROM NEILLSVILLE AND ARCADIA WI...TO CHARLES
CITY IA WHERE NOSE OF 850-700MB MOISTURE TRANSPORT/ISENTROPIC LIFT
WILL BE DIRECTED. LOOK LIKE TEMPERATURES SHOULD BE RIGHT AROUND
NORMAL IN THE MID-UPPER 70S.
LOOK FOR THE MID-LEVEL TROUGH TO ROTATE OVER/ACROSS THE AREA SUNDAY
NIGHT INTO MONDAY FOR A GOOD CHANCE OF SHRA/ISOLD THUNDER. HIGHS
SUNDAY AND MONDAY ARE EXPECTED TO CONTINUE RIGHT AROUND NORMAL IN
THE MID 70S TO A FEW LOWER 80S.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
247 PM CDT FRI JUN 1 2012
01.12Z GFS/ECMWF APPEAR TO BE HAVING PROBLEMS RESOLVING WHERE
EXACTLY OMEGA BLOCK HIGH IS GOING TO SET UP THROUGH THE PERIOD. THE
GFS/ECMWF SEEM TO HAVE FLIP-FLOPPED WITH EACH OTHER/S SOLUTION.
EITHER WAY...APPEARS THE AREA WILL REMAIN JUST EAST OF THIS
RIDGE/OMEGA BLOCK AND WILL BE SUSCEPTIBLE TO CYCLONIC FLOW ALOFT
WITH EMBEDDED IMPULSES. THIS YIELDS SLIGHT CHANCE OF SHOWERS EACH
DAY. OTHERWISE...HIGH TEMPERATURES SHOULD REMAIN RIGHT AROUND NORMAL
LEVELS IN THE 70S.
&&
.AVIATION...
1100 AM CDT FRI JUN 1 2012
WEAK HIGH PRESSURE WILL INFLUENCE THE REGION THIS AFTERNOON...WITH
BUFKIT SOUNDINGS AND SATELLITE TRENDS SUPPORTING CU DEVELOPMENT. SEE
SOME POTENTIAL FOR SCT/ISOLD -SHRA. HRRR KEEPS THIS EAST OF THE TAF
SITES...CLOSE TO THE UPPER LEVEL LOW/SHORTWAVE ENERGY AND THE BETTER
MOISTURE. WILL KEEP ANY -SHRA OUT OF TAFS FOR NOW.
A BIT OF UPPER LEVEL ENERGY WILL SPIN SOUTHEAST ACROSS THE NORTHERN
PLAINS TONIGHT...ACROSS IA EARLY ON SAT. ANOTHER PIECE OF ENERGY IS
THEN EXPECTED TO DROP DOWN THE BACKSIDE OF THE DEPARTING UPPER LEVEL
TROUGH SAT AFTERNOON/EVENING. BOTH FEATURES COULD PRODUCE SOME
-SHRA. BELIEVE THE RAIN CHANCES SHOULD STAY WEST OF KRST
TONIGHT...WHILE SAT AFT/EVENING COULD BRING ISOLD -SHRA TO KLSE.
EXPECT SOME INCREASE IN HIGH CLOUDS LATER TODAY FROM THE NORTHERN
PLAINS SHORTWAVE. OVERALL...VFR CONDITIONS SHOULD PERSIST INTO SAT
NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
247 PM CDT FRI JUN 1 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
236 PM CDT FRI JUN 1 2012
.SHORT TERM...TONIGHT AND SATURDAY.
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN UPPER
LEVEL LOW PRESSURE SYSTEM MOVING INTO SOUTHWEST LOWER MICHIGAN EARLY
THIS AFTERNOON. A SHORTWAVE ROTATING AROUND THIS UPPER LOW IS
GENERATING A BAND OF LIGHT RAIN THAT IS PIVOTING INTO DOOR COUNTY.
PARTLY TO MOSTLY CLOUDY CONDITIONS RESIDE ELSEWHERE WITH
TEMPERATURES MAINLY INTO THE LOW TO MID 60S. AS THE UPPER LOW
SLOWLY MOVES NORTH OVER THE NEXT 24 HOURS...SMALL PRECIP CHANCES ARE
THE MAIN FORECAST CONCERN.
TONIGHT...THE NAM BECOMES A SOUTHERN OUTLIER WITH THE TRACK OF THE
SURFACE LOW BY 12Z SATURDAY SO USED THE GFS AND ECMWF MOSTLY FOR
THIS FORECAST. NEARLY VERTICALLY STACKED LOW PRESSURE WILL SWING
NORTH OVER LOWER MICHIGAN TO FAR SOUTHERN ONTARIO BY SATURDAY
MORNING. SATELLITE/RADAR TRENDS SUPPORT KEEPING A CHANCE OF SHOWERS
OVER FAR NE WISCONSIN THIS EVENING...BUT LOW TO MID-LEVEL WINDS WILL
EVENTUALLY BACK AROUND TO THE NORTHWEST AND WILL BRING IN DRIER AIR
BELOW 500MB INTO CENTRAL AND NORTHEAST WISCONSIN. AS A RESULT...THE
COLUMN WILL QUICKLY DRY OUT OVER MOST LOCATIONS EXCEPT FOR MAYBE
DOOR COUNTY WHERE A CHANCE OF SHOWERS WILL REMAIN THROUGH THE
NIGHT. THE PRESSURE GRADIENT DOES TIGHTEN TONIGHT AND SHOULD STILL
HAVE A MID/HIGH DECK OVERHEAD...SO THINK LOWS WILL BE WARMER THAN
LAST NIGHT. WILL GO WITH LOWS MAINLY IN THE 40S.
SATURDAY...THE LOW PRESSURE SYSTEM WILL MOVE SLIGHTLY TO THE
NORTHEAST...WHICH MEANS THE DEEPEST MOISTURE WILL REMAIN OVER DOOR
COUNTY. ELSEWHERE...THE INFLUX OF DRIER AIR WILL LEAD TO A PARTLY
TO MOSTLY CLOUDY START TO THE DAY. WARMING LOW LEVEL TEMPERATURES
WILL LEAD TO STEEP LOW LEVEL LAPSE RATES DEVELOPING BY
MIDDAY...WHICH YIELD 100-200 J/KG OF ML CAPE THROUGH THE AFTERNOON.
SHOULD SEE A WIDESPREAD CU FIELD DEVELOP AS A RESULT. NOT SURE IF
THE CU WILL GROW LARGE ENOUGH FOR SHOWERS. MID-LEVEL HEIGHTS WILL
BE RISING THROUGH THE AFTERNOON...THOUGH MODELS ARE HINTING AT A
SURFACE TROUGH DROPPING SOUTH OVER NORTHEAST WISCONSIN THAT COULD
INTERACT WITH THE INSTABILITY TO GENERATE THOSE SHOWERS...AND
POSSIBLY A RUMBLE OF THUNDER. WILL REMOVE POPS OUTSIDE OF DOOR
COUNTY FOR THE MORNING...BUT WILL LEAVE THEM FOR THE AFTERNOON IN
CASE THAT SURFACE TROUGH DOES APPEAR. HIGHS IN THE UPPER 60S TO
LOWER 70S.
.LONG TERM...SATURDAY NIGHT THRU NEXT FRIDAY. TIMING BEST PRECIP
CHANCES AND TEMPS CONTINUE TO BE MAIN FORECAST CHALLENGES.
THE VERTICALLY STACKED SYSTEM RESPONSIBLE FOR THE COOL WEATHER
OVER THE AREA WILL CONTINUE TO SLOWLY PUSH AWAY FROM THE AREA ON
SATURDAY NIGHT...ALLOWING SOME DRIER AIR TO WORK IN...BRINGING AN
END TO ANY SHOWER ACTIVITY. OTHER THAN SOME LINGERING SLIGHT
CHANCE POPS ACROSS THE THE AREA IN THE EVENING...WILL CONTINUE
WITH A DRY FORECAST FOR THE OVERNIGHT HOURS. CLOUDS WILL DECREASE
THROUGH THE EVENING AS THE DRY AIR WORKS INTO THE AREA...ALLOWING
TEMPS TO DROP INTO THE 40S NORTH...AND LOW 50S SOUTH. WEAK
MID/UPPER RIDGING BUILDS ACROSS THE UPPER MIDWEST AND WESTERN
GREAT LAKES ON SUNDAY...BRINGING DRY WEATHER AND A RETURN TO ABOVE
NORMAL TEMPERATURES.
AS THE RIDGE FLATTENS OVER THE WESTERN GREAT LAKES...AND BUILDS
OVER THE NORTHERN PLAINS...ANOTHER PIECE OF SHORTWAVE ENERGY IS
FORECAST TO RIDE ON THE EASTERN SIDE OF THE RIDGE SUNDAY NIGHT.
ECMWF/GFS/NAM ALL SHOW THIS FEATURE...WHILE THE CANADIAN IS
STRONGER WITH THE RIDGE AND KEEPS THE SHORTWAVE ENERGY OVER
SOUTHERN CANADA. GFS HAS SLOWED DOWN WITH ITS TIMING...ALIGNING
BETTER WITH THE ECMWF. SOME MINOR TIMING/STRENGTH DIFFERENCES
STILL REMAIN...BUT HARD TO IGNORE THE MAJORITY OF GUIDANCE...SO
WILL CONTINUE WITH SHOWER/STORM CHANCES ON SUNDAY NIGHT AND INTO
MONDAY. INSTABILITY AND FORCING NOT OVERLY IMPRESSIVE...SO WILL
KEEP POPS IN THE 20-40 PERCENT RANGE...AND ONLY MENTION ISOLATED
THUNDER.
PLENTY OF QUESTIONS REMAIN FOR THE MID TO LATE WEEK PERIOD...AS A
VERY BLOCKY PATTERN SETS UP OVER THE CONUS. MODELS HANDLE JUST
HOW BLOCKY THE PATTERN WILL BE DIFFERENTLY...LEADING TO LOW
CONFIDENCE ON WHEN THE BEST CHANCE FOR SHOWER/STORMS WILL BE.
MODELS CONTINUE TO SHOW WEAK PIECES OF ENERGY ROTATING AROUND THE
UPPER LOW THE EASTERN SEABOARD...EACH OF WHICH WOULD BRING A
CHANCE OF SHOWERS TO THE AREA. GFS IS THE MOST AGGRESSIVE WITH A
POTENT SHORTWAVE DROPPING SOUTH INTO WI ON MONDAY NIGHT. OTHER
MODELS WEAKER AND SLOWER WITH THIS FEATURE. HARD TO RULE OUT
ISOLATED ACTIVITY DEVELOPING WITH DAYTIME HEATING DURING THE MID
TO LATE WEEK PERIOD...SO WILL CONTINUE WITH SLIGHT CHANCE POPS TO
COVER...AS CONFIDENCE NOT HIGH ENOUGH TO BUMP POPS HIGHER.
HIGH TEMPS A LITTLE TRICKY FOR NEXT WEEK...WITH RIDGING TRYING TO
BUILD INTO THE AREA...BUT PERSISTENT EAST WINDS NOT ALLOWING THE
REAL WARM AIR TO MAKE IT TO EASTERN WI. WILL CONTINUE USE A "MIDDLE
OF THE ROAD" APPROACH...WITH HIGHS GENERALLY IN THE 70S AWAY FROM
THE LAKE.
&&
.AVIATION...VFR CONDITIONS TO PREVAIL THROUGH TOMORROW. WIDELY
SCATTERED SHOWERS ARE POSSIBLE THIS AFTERNOON OVER EASTERN WISCONSIN
AS AN UPPER LOW SLOWLY MOVES NORTH ACROSS THE REGION. DEEPER
MOISTURE RESIDES OVER LOWER MICHIGAN...AND SOME OF THIS MOISTURE MAY
BRUSH FAR NE WISCONSIN TONIGHT INTO TOMORROW. THE HIGHEST SHOWER
CHANCES WILL REMAIN THERE. WILL HAVE MORE INSTABILITY FOR SHOWER
CHANCES TOMORROW AFTERNOON THAN TODAY...AND HAVE KEPT THE SCT SHOWER
MENTION OVER EASTERN WISCONSIN. NW WINDS MAY ALSO TURN GUSTY
TOMORROW MORNING.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/BERSCH