Area Forecast Discussion Issued by NWS Albany, NY
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000
FXUS61 KALY 240729
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
327 AM EDT FRI MAY 24 2013
.SYNOPSIS...
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A COLD FRONT WILL STALL ALONG THE ATLANTIC SEABOARD TODAY. A STORM
WILL DEVELOP...INTENSIFY...AND LINGER ON THIS FRONT NEAR THE NEW
ENGLAND COAST THROUGH MUCH OF THE WEEKEND. THE STORM WILL DRAW MUCH
COOLER AIR INTO THE REGION AND BRING DAMP WEATHER FOR MUCH OF THE
WEEKEND. HIGH PRESSURE WILL BUILD INTO THE EASTERN GREAT LAKES
MEMORIAL DAY AND DRIFT OVER OUR REGION INTO MIDWEEK...WITH FAIR DRY
AND WARMER WEATHER RETURNING.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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FLASH FLOOD WATCH IS BEING CANCELED SINCE THERE IS NO MORE
CONVECTIVE RAINFALL IN THE REGION...AND A STEADIER LONG TERM RAIN IS
EXPECTED INTO THE WEEKEND.
UPPER LOW STILL FORMING...AND AREA OF RAIN IS SLOWLY BUILDING EAST.
RAIN COVERAGE IS A BIT PATCHIER TO THE WEST...BUT EVEN WESTERN AREAS
SHOULD SEE OCCASIONAL RAIN...JUST NOT AS STEADY AS EASTERN NY AND
WESTERN NEW ENGLAND. THE SURFACE WIND SHIFT BOUNDARY IS MOSTLY
THROUGH THE AREA...ALTHOUGH THE WINDS HAVE GONE CALM IN SOME AREAS.
UPSTREAM...THE NORTHWEST TO NORTH WINDS ARE STRONGER AND THESE WINDS
AND COOLER TEMPERATURES SHOULD SPREAD EAST THROUGH THE DAY.
TEMPERATURES SHOULD HOLD STEADY OR SLOWLY FALL THROUGH THE DAY IN
MOST AREAS. SOME WESTERN AREAS COULD RECOVER A COUPLE OF DEGREES
DEPENDING ON WHERE THE WESTERN EDGE OF PRECIPITATION SETS UP.
BOUNDARY LAYER THERMAL GRADIENT SHOULD BE SLOW TO PUSH EAST...SO
EVEN WITH RAIN...EASTERN NY AND WESTERN NEW ENGLAND COULD RISE A
DEGREE OR TWO...BUT AGAIN...FOR ALL PRACTICAL PURPOSES...
TEMPERATURES SHOULD HOLD STEADY THEN SLOWLY FALL THROUGH THE
AFTERNOON.
TONIGHT...RAIN SHOULD CONTINUE...WITH MORE RAIN DEVELOPING
ASSOCIATED WITH THE DEEPENING UPPER LOW...INCLUDING WESTERN
AREAS...WHERE RAIN ASSOCIATED MORE DIRECTLY WITH THE UPPER LOW
SHOULD TRACK INTO THE AREA. TEMPERATURES SHOULD CONTINUE TO
FALL...INTO THE 40S IN MANY AREAS...AND UPPER 30S IN THE SOUTHERN
ADIRONDACKS.-- End Changed Discussion --
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
THE OOUTC GFS/ECMWF/GEM ARE IN AGREEMENT AND IN LINE WITH PAST
FEW RUNS OF THE MODEL SUITE. ONLY DIFFERENCE IN 00UTC RUNS IS NAM
IS A BIT FASTER WITH PROGRESSION OF WEEKEND WEATHER SYSTEM...BUT
ITS BEEN THE FAST MODEL FOR SVRL RUNS...AND AT THIS TIME ITS
PROBABLY THE OUTLIER.
BY SAT MORNING THE 500HPA CUT OFF WILL BE CENTERED OVER SOUTHEAST
NEW YORK...AND COVER MUCH OF THE NORTHEAST. THE SURFACE LOW WILL
BE CENTERED JUST OFF BOSTON. 500HPA CUT OFF WILL TAKE ON A NEG
TILT SAT...AND ENHANCE COOL CONVEYOR BELT PCPN FM COASTAL
LOW...BACK INTO MOST OF THE FCA. WITH COASTAL LOW ALMOST
VERTICAL...12MB PRESSURE GRADIENT ACROSS NYS...IT SHOULD BE A RAW
NOVEMBER-ESQ DAY WITH OCCASIONAL LIGHT RAIN AND A BRISK CHILLY
NORTH WIND. H850 TEMPS FALL TO -2 TO -4C OVER FCA...COLD ENOUGH TO
ALLOW SNOW OVER HIGHEST TRRN. (YES ITS MAY 25TH IN NEW YORK WERE
TALKING ABOUT HERE). AT SFC HIGH TEMPS SAT WILL BE IN MID 40S TO
MID 50S...15-20 DEG BLO NRML. LOWS SAT NT WILL FALL TO MID 30S TO
LOW 40S. PCPN AMOUNTS WILL BE GREATEST ON EAST SIDE OF FCA AND
OVER HIR TRRN...DIMINISHING TWRD THE WEST. DURING SAT AND SAT NT
ANOTHER 0.30 TO 1.0 INCHES OF QPF IS FCST BY GFS...0.10 TO 0.5 BY
GEM...AND A TENTH TO AN INCH BY THE "FAST" NAM WHICH IS ALL EAST
OF THE HUDSON RIVER
THE GEM/ECMWF/GFS TAKE THE VERTICAL LOW PRESSURE SYSTEM INTO THE
GULF OF MAINE SUNDAY AND ONWARD INTO THE MARITIMES...IN LINE WITH
CURRENT FCST. PCPN SHOULD DIMINISH TO SCT -SHRA EAST...ISOLD -SHRA
WEST...TIED MAINLY TO LAST OF SHORT WVS SPIRALING AROUND 500HPA
CUT OFF...DIURNAL HEATING AND TRRN. CLOUDS WILL LINGER MUCH OF THE
DAY...ALTHOUGH BREAKS OF SUN WILL INCR ALONG W PERIPHERY OF
FCA...AND IN THE SOUTHEAST. MOST OF AREA HAS A CHANCE TO SEE
SUNSET SUN EVENING. WITH LESS PCPN...SOME SUN MAX TEMPS WILL
RECOVER TO THE MID 50S TO LOW 60S WITH SOME MID 60S SE ON SUNDAY.
SUNDAY NIGHT THE CUT OFF EXITS INTO LABRADOR...AND THE BEGINNINGS
OF THE NEXT MAJOR PATTERN CHANGE TAKE SHAPE AS A 500HPA RIDGE
BUILDS FM MISS VLY TO HUDSON BAY CANADA AND THEN STARTS BUILDING
EAST.
AT THE SFC LARGE HIGH BUILDS INTO THE EASTERN GRTLKS MONDAY...AND
ACROSS FCA MON NT. UNDER STRONG SUNSHINE AND LIGHT WINDS TEMPS
WILL REBOUND INTO THE 60S WITH LOW 70S IN VLYS SOUTH AND EAST OF
ALB.
MONDAY NIGHT WILL BE CHILLY UNDER CLEAR SKIES...LIGHT WINDS UNDER
THE SFC HIGH...AND LOWS IN 30S AND LOW 40S. THERE MAY BE FROST AND
FREEZE ISSUES PARTICULARLY OVER THE HIR TRRN.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
THE PATTERN CHANGE THAT SET UP MONDAY...BECOMES THE DOMINATE
REGIME DURING THE EFP. 500HPA RIDGE BUILDS FM GULF COAST TO JAMES
BAY...THEN SHIFTS TO EASTERN SEABOARD. 590DM CLOSED HIGH OVER MUCH
OF EAST FROM LATE WED INTO WEEKEND. THIS SIGNAL HAS BEEN THERE FOR
DAYS IN GFS...AND THERE`S MORE AGREEMENT BWTN GFS/GEM/12UTC ECMWF
AND ENSEMBLES IN DAYS 5-7 THAN IN THE SHORT TERM.
AT SFC COOLER BUT MODERATED CANADIAN HIGH HOLDS OVER RGN TUES
BEFORE SLIDING OFFSHORE. WAA BEGINS POURING OVER TOP OF 500HPA
RIDGE AS SFC WMFNT SURGES THROUGH FCA TUES NT AND WED WITH
-SHRA/TSTMS. THIS HAS ALL THE HALLMARKS OF MCS RIDGE ROLLERS.
BY WED EVENING FCA AND MUCH OF USA FROM ROCKIES TO THE SEABOARD IS
UNDER THE EASTERN RIDGE...AND BERMUDA HIGH. TEMPERATURES WHICH
STARTED THE WEEK WELL BLO NORMAL WILL SURGE TO 70S TUES...MID 70S
TO LOW 80S WED...THE 80S THURS AND TWRD 90 FRI.
WILL POPULATE WITH OVERNIGHT WPC GRIDS. ECMWF CLOSE ENOUGH AT THIS
TIME TO GFS.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
UNSETTLED WEATHER WITH POOR FLYING CONDITIONS WILL PERSIST THROUGH
MUCH OF THE 24 HOUR PERIOD ENDING 06Z SATURDAY. WITH PERIODS OF RAIN
THROUGH THE DAY...IFR CONDITIONS SHOULD DOMINATE...WITH OCCASIONAL
FLUCTUATIONS BETWEEN MVFR AND IFR. AFTER 01Z-03Z...VCSH WITH
POTENTIAL SLOW IMPROVEMENTS TO CEILINGS INTO SOLID MVFR...BORDERING
ON LOW VFR. WITH THE POTENTIAL FOR RAIN TO SHIFT A BIT EAST OF THE
TAF SITES BY THE EVENING...VISIBILITIES COULD IMPROVE TO VFR.
LIGHT WEST OT NORTHWEST WINDS EARLY THIS MORNING SHOULD BECOME
NORTHWEST TO NORTH THROUGH THE DAY AT AROUND 10 KT. THERE COULD BE
SOME GUSTS BETWEEN 15 KT AND 20 KT LATE THIS AFTERNOON AND
EVENING...BUT REMAINING STEADY AROUND 10 KT THIS EVENING.
OUTLOOK...
FRI NIGHT-SAT...MVFR/IFR. -SHRA LIKELY. BREEZY NORTH WINDS.
SAT NGT-SUN...VFR/MVFR...CHC -SHRA. BREEZY NORTH WINDS.
SUN NGT-TUE...VFR. NO SIG WX.
&&
.FIRE WEATHER...
WET CONDITIONS FOR FRIDAY...
NO FIRE WEATHER CONCERNS INTO SUNDAY. PERIODS OF RAIN WILL CONTINUE
INTO THE HOLIDAY WEEKEND. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE
POSSIBLE TUESDAY NIGHT AND WEDNESDAY.
&&
.HYDROLOGY...
LOW PRESSURE WILL ORGANIZE AND LINGER ALONG THE NEW ENGLAND COAST
INTO LATE SATURDAY BEFORE DRIFTING INTO THE MARITIMES. IT WILL
BRING ONE TO TWO INCHES OF RAIN ACROSS THE REGION THROUGH SUNDAY
MORNING. THE THE GREATEST AMOUNTS OVER THE EAST...AND LEAST
ACROSS THE WEST.
THIS RAINFALL WILL COME ON ALREADY SATURATED SOILS ACROSS MUCH OF
THE FORECAST AREA DUE TO THE PERIODS OF HEAVY/TORRENTIAL RAINFALL
THAT HAS OCCURRED DURING THE PAST TWO DAYS.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...NAS
FIRE WEATHER...SNYDER
HYDROLOGY...SNYDER