FXUS61 KBOX 141028
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
628 AM EDT SUN MAR 14 2010
.SYNOPSIS...
A MAJOR NOREASTER STALLED NEAR THE MID ATLANTIC COAST WILL PRODUCE
PERIODS OF HEAVY WINDSWEPT RAINS TODAY THROUGH MONDAY...THEN DRIFT
OUT TO SEA SOUTHEAST OF NANTUCKET LATE MONDAY NIGHT. STRONG HIGH PRESSURE
FROM THE GREAT PLAINS FOLLOWS...DELIVERING A SPELL OF VERY NICE
SPRING WEATHER HERE FOR MUCH OF THE MIDDLE AND END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
996 MB LOW PRESSURE WAS LOCATED OFF THE CENTRAL NEW JERSEY COAST
OR JUST SOUTH OF THE 44025 BUOY SOUTH OF FIRE ISLAND EARLY THIS
MORNING. A TIGHT PRESSURE GRADIENT WIND WITH A 75 KT EASTERLY LOW
LEVEL JET BETWEEN THE LOW AND CANADIAN MARITIMES SURFACE HIGH...HAS
BEEN RESPONSIBLE FOR DAMAGING WIND GUSTS PRIMARILY ALONG THE COASTAL
PLAIN EARLY THIS MORNING.
A TROWAL SIGNATURE...ASSOCIATED WARM CONVEYOR BELT AND PRECIPITABLE
WATER VALUES AROUND 1G/KG HAS BEEN RESPONSIBLE FOR HEAVY RAINFALL
THIS MORNING. AN IMPRESSIVE PLUME OF MOISTURE IS NOTED ON THE WATER
VAPOR LOOP EMANATING FROM THE CARIBBEAN. THE BEST OMEGA IS EXPECTED
TO LIFT INTO THE NORTHERN ZONES THIS AFTERNOON. HOWEVER TOTAL TOTALS
ARE EXPECTED TO INCREASE INTO THE MID 50S FOR A TIME THROUGH MIDDAY
AS MID LEVEL LAPSE RATES REMAIN UNSTABLE. COULD SEE ISOLATED
THUNDERSTORMS WITH ADDITIONAL CONVECTIVE BANDS OF PRECIPITATION
SOUTH OF THE AREA WITH MORE SHOWERY RAINFALL TODAY. CURRENTLY
LIGHTNING IS BEING DETECTED OFF THE MID ATLANTIC COAST...SO ADDED
SLIGHT CHANCE THUNDER IN THE GRIDS.
WINTER WEATHER...MIXED SNOW...SLEET AND FREEZING RAIN HAS EITHER
MIXED WITH OR CHANGED TO RAIN ACROSS MUCH OF NORTHWESTERN
MASSACHUSETTS AND SOUTHWESTERN NEW HAMPSHIRE. PRECIPITATION WILL
FALL AS MOSTLY RAIN TODAY AS THICKNESSES CONTINUE TO RISE. A FEW
POCKETS OF MIXED PRECIPITATION WILL PERSIST ACROSS THE EAST SLOPES
OF THE BERKSHIRES AND SOUTHERN NEW HAMPSHIRE...BUT TEMPERATURES ARE
EXPECTED TO REMAIN JUST ABOVE FREEZING. THEREFORE THE WINTER WEATHER
ADVISORY HAS BEEN ALLOWED TO EXPIRE.
WIND...A HIGH WIND WARNING REMAINS IN EFFECT ALONG THE COASTAL PLAIN
UNTIL 8 AM. THE HIGH WIND WARNING WILL LIKELY NEED TO BE CONVERTED TO
A WIND ADVISORY ACROSS PORTIONS OF THE NORTHEAST MASSACHUSETTS COAST.
ELSEWHERE WINDS ARE EXPECTED TO DIMINISH AS THE LOW LEVEL JET LIFTS
NORTH.
HYDRO...PLEASE SEE SECTION BELOW. STEADY RAIN EXPECTED TO TAPER TO
SHOWERS TODAY...EXCEPT FAR NORTHERN SECTIONS INVOF LOW LEVEL JET AND
PWAT AXIS.
COASTAL FLOOD...PLEASE SEE SECTION BELOW. HAVE ANOTHER HIGH TIDE
OCCURRING AROUND 10AM TO NOON. DO HAVE A COASTAL FLOOD WARNING IN
EFFECT...WITH HIGH SEAS AND A STORM SURGE OF AROUND 2 FEET ALONG THE
EASTERN MASSACHUSETTS COAST WITH A COASTAL FLOOD ADVISORY ACROSS
CAPE COD AND NANTUCKET ISLAND. MINOR TO MODERATE FLOODING APPEARS A
GOOD BET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...LOW CENTER EXPECTED TO BECOME VERTICALLY STACKED SOUTH OF
NEW ENGLAND. THIS WILL ALLOW THE LOW LEVEL JET TO GRADUALLY DIP SOUTH
ACROSS THE AREA. SO STEADIER PRECIPITATION AND INCREASING WIND CAN BE
EXPECTED TO RESUME TONIGHT.
WIND...A WIND ADVISORY WILL LIKELY BE NEEDED NEAR THE COAST WITH
SUSTAINED WINDS OF 25 TO 30 KT AND GUSTS BETWEEN 40 TO 45 KT
POSSIBLE.
WINTRY WEATHER...PRECIPITATION IS PRIMARILY EXPECTED TO FALL AS
RAIN. ACROSS THE FAR INTERIOR...TEMPERATURES ARE EXPECTED TO COOL
OVERNIGHT...SO THAT SOME MIXTURE OF SLEET AND SNOW CAN BE EXPECTED.
CURRENTLY FORECASTING AN ADDITIONAL INCH OR TWO OF SLUSHY
ACCUMULATION POSSIBLE PRIMARILY ACROSS THE HIGHER TERRAIN.
HYDRO...PLEASE SEE SECTION BELOW. THE FLOOD WATCH CONTINUES THROUGH
THE TONIGHT TIMEFRAME. LOW LEVEL JET DIPS SOUTH PROVIDING MORE
STEADY RAINFALL ACROSS MUCH OF THE AREA.
COASTAL FLOOD...PLEASE SEE SECTION BELOW. HAVE ANOTHER HIGH TIDE
OCCURRING AROUND 10PM TO MIDNIGHT. DO HAVE A COASTAL FLOOD WATCH
IN EFFECT...WITH HIGH SEAS AND A STORM SURGE OF AROUND 2 FEET ALONG
THE EASTERN MASSACHUSETTS COAST. MINOR TO MODERATE FLOODING APPEARS
A GOOD BET.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
COASTAL STORM LINGERS THROUGH MONDAY EVENING AND THE COLUMN COOLS.
CONTINUED STRONG EASTERLY MOIST CONVEYOR BELT IN CYCLONIC FLOW WITH
LIFT FROM THE HILLS AND COASTAL-SEA INTERFACE PRODUCES PERIODS OF
MODERATE PRECIPITATION WITH TOPS TO AROUND 10 TO 12000 FT.
PRECIPITATION...BECAUSE WE THINK ODDS ARE THAT RAIN WILL BE IN THE
PROCESS OF CHANGING TO SNOW ACROSS A CONSIDERABLE PORTION OF SOUTHERN
NEW ENGLAND DURING THE LATE MORNING TO EVENING HOURS...THEN ENDING AS
DRIZZLE OR SPRINKLES FROM NORTHWEST TO SOUTHEAST WHEN POTENTIAL ICE
NUCLEATION CONTRIBUTION FROM LIFT WEAKENS DISAPPEARS.
HOW MUCH SNOW? RIGHT NOW...BECAUSE OF TEMPS GENERALLY JUST ABOVE
FREEZING WE THINK ACCUMULATION WILL HAVE TO BE LIMITED TO LESS THAN
3 INCHES. AS PER PREVIOUS SHIFTS...A LOW PROB OF ADVISORY AMOUNTS.
INCIDENTALLY...WHILE IT LOOKS LIKE THE NAM QPF AMOUNTS ARE GOING TO
HAVE BEEN THE BEST FEATURE OF ITS RECENT CYCLES... ITS THERMAL PROFILE
JUST ABOVE THE BL HAS BEEN POOR... WITH THE GFS/EC A BETTER FIT. THE
RESULT WAS AT LEAST 1/2 TO 2 INCHES OF WET SNOW LAST NIGHT FROM THE
SLOPES OF THE BERKS TO THE MONADNOCKS...ALL ABOVE 1000 FT.
THEREFORE... THE FCST GRIDS ON MONDAY GENERATED SNOW FROM A 30 30 40
NAM-GFS-ECMWF BLEND OF PARTIAL THICKNESSES. IF WE WERE TO ACCEPT THE
ECMWF AT FACE VALUE...WE'D BE SLIGHTLY COLDER AND SHOW MORE SNOW.
SO...IT COULD GET INTERESTING IN BOSTONS NORTHWEST SUBURBS TO THE
MONADNOCKS AND WORCESTER HILLS...THO NOT A MAJOR EVENT...BUT STILL
INTERESTING FOR THE WANING WINTER.
NORTHEAST WINDS WILL INCREASE AGAIN AS THE ENVELOPE OF STRONG WIND
PULLS SOUTHWESTWARD AND THEN SOUTHEASTWARD AS THE SFC LOW FINALLY
MAKES ITS MOVE OUT TO SEA. WIND ADVISORIES APPEAR LIKELY MONDAY
OVER FOR MUCH OF EASTERN NEW ENGLAND.
RAPID CLEARING TAKES PLACE LATE MONDAY NIGHT.
THEREAFTER...MUCH OF NEXT WEEK FROM TUESDAY AFTERNOON ONWARD LOOKS
VERY VERY GOOD...LOTS OF SUN AND WARMING TEMPS...WITH 60 TO 65 DEGREES
FOR A DAY OR 2! LOTS OF ABOVE NORMAL DAYTIME TEMPS .. AWAY FROM THE
INFLUENCE OF WHAT WILL PROBABLY BE COASTAL COOLING SEA BREEZES ON
MOST DAYS.
WE'VE ADDED POPS AND QPF TO NEXT WEEKEND PER EC/GFS AND NAEFS CONSISTENT
SIGNAL THE PAST DAY OR 2...LOOKS LIKE A N-S HIGH AMPLITUDE COLD FRONT.
GRIDS ON THIS SHIFT WERE FULLY UPDATED THROUGH NEXT SUNDAY WITH 00Z/14
GFS GUIDANCE MODULATED BY THE NAM IN THE SHORTER TERM THRU 12Z WEDNESDAY
AND THEREAFTER BY THE ECMWF.
FOR THOSE WHO RELY ON MOS GUIDANCE...PLEASE CONSIDER BLENDING THE
ECMWF DEWPOINTS WITH THE NCEP MOS GUIDANCE...ESPECIALLY ONSHORE FLOW.
THERE SEEMS TO BE SOME SORT OF RELUCTANT BIAS IN THE MOS DEWPOINT
GUIDANCE...ESPECIALLY GFS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
TODAY...GENERAL IFR CONDITIONS EXPECTED WITH CEILINGS 5000-1000 FT.
LOW CONFIDENCE WE COULD SEE BRIEF IMPROVEMENT TO MVFR WITH CEILINGS
TEMPO 1500 FT. LOW LEVEL WIND SHEAR THROUGH 15Z THIS MORNING. ESE
LOW LEVEL JET AROUND 75 KT TRAVERSES THE COAST AND LIFTS FROM S TO N.
AIRPORT WEATHER WARNINGS HAVE BEEN POSTED FOR STRONG WINDS ALL RHODE
ISLAND AIRPORTS UNTIL 8 AM...BOSTON LOGAN AIRPORT UNTIL NOON. E WIND
GUSTS TO 45 KT WILL GRADUALLY DIMINISH BY AFTERNOON. STRONGEST WINDS
WILL REMAIN ACROSS THE NORTH SHORE OF BOSTON THIS AFTERNOON.
ISOLD THUNDER POSSIBLE THROUGH 18Z TODAY PRIMARILY CT...RI AND SE
MASSACHUSETTS.
LIGHT MIXED SN/PL/RA FAR NORTHWEST HIGH TERRAIN WILL BE SPOTTY TODAY.
OUTLOOK...MONDAY THROUGH THURSDAY...
MONDAY...MVFR/IFR CONDITIONS IN INTERMITTENT RAIN/DRIZZLE CHANGING TO
SNOW FROM NW TO SE DURING THE MIDDAY HOURS. NORTHEAST WIND GUSTS TO AROUND
40 KT LIKELY MOST TERMINALS...ESPECIALLY EAST COAST OF MASS AS WELL
AS RI. IMPROVEMENT TO VFR FROM N TO S AT NIGHT.
TUE-THU...VFR AND LESS WIND EXPECTED FOR MUCH OF THE UPCOMING WEEK
WITH NO MAJOR WEATHER SYSTEMS ANTICIPATED.
&&
.MARINE...
TODAY...STORM WARNINGS WILL BE CONVERTED TO SMALL CRAFT ADVISORIES OR GALES
ACROSS THE SOUTHERN WATERS. STORM WARNINGS CONTINUE ACROSS THE
EASTERN WATERS. DANGEROUS SEAS TODAY 17 TO 23 FT. MARINERS URGED TO
REMAIN IN PORT.
TONIGHT...GALE WARNINGS LIKELY EXCEPT SCA S COAST. DANGEROUS SEAS 17
TO 22 FEET TONIGHT. MARINERS URGED TO REMAIN IN PORT.
OUTLOOK...MONDAY THROUGH THURSDAY...
GALES CONTINUE THROUGH MONDAY THEN GRADUALLY DIMINISH MONDAY NIGHT
THROUGH TUESDAY. SEAS WILL REMAIN DANGEROUS THROUGH MONDAY NIGHT...ESPECIALLY
EAST OF THE EASTERN MASS COASTLINE. WINDS AND SEAS CONTINUE TO
DIMINISH TUESDAY THROUGH THURSDAY AS HIGHER PRESSURE BUILDS IN.
NO 00Z/14 SWANGFS AVBL FOR THE GUIDANCE.
&&
.HYDROLOGY...
MAINSTEM FLOOD CONCERNS INCLUDE MANY LOCATIONS IN THE MERRIMACK
BASIN OF NE MA. LATEST NERFC GUIDANCE BRINGS SEVERAL POINTS INTO
MINOR OR BORDERLINE MODERATE FLOODING BEGINNING TONIGHT...WHICH IS
BASED UPON FORECAST RAINFALL. DECIDED TO HOLD OFF ON ISSUING FLOOD
WARNINGS FOR MOST OF THESE LOCATIONS /ASIDE FROM SUDBURY RIVER/
GIVEN SOME UNCERTAINTY.
SAME HOLDS TRUE FOR BLACKSTONE...NEPONSET AND CHARLES RIVERS THOUGH
IT LOOKS MORE BORDERLINE AS TO WHETHER OR NOT THESE LOCATIONS REACH
FLOOD STAGE.
MINOR FLOODING APPEARS LIKELY ALONG FARMINGTON RIVER AT UNIONVILLE
AND SIMSBURY CT BY THIS EVENING...AND WE MAY NEED TO EXTEND WARNING
FARTHER DOWNSTREAM INTO TARIFFVILLE LATER TODAY.
AXIS OF HEAVIEST RAINFALL HAS BEEN ACROSS NE CT...RI AND
CENTRAL/EASTERN MA WHERE 2-4 INCH TOTALS HAVE BEEN WIDELY OBSERVED
UP TO 5 AM EDT. FLOOD WARNING REMAINS POSTED FOR THESE AREAS UNTIL
1230 PM...AND WILL PROBABLY NEED TO BE EXTENDED THROUGH AFTERNOON.
THIS IS FOR WIDESPREAD URBAN AND SMALL STREAM FLOODING.
DECIDED TO EXPAND AREAL WARNING INTO HARTFORD/TOLLAND COUNTIES EVEN
THOUGH AMOUNTS HAVE BEEN A LITTLE LOWER. IN PARTICULAR BUNNEL BROOK
IN BURLINGTON CT JUST REACHED FLOOD STAGE AT 5 AM AND IS EXPECTED TO
CREST THIS MORNING IN MINOR FLOOD.
&&
.TIDES/COASTAL FLOODING...
THE FCST FOR TONIGHT AND MONDAY IS PREDICATED ON RESULTS FROM MIDDAY
TODAY. SO...STATUS QUO ON THE WATCH/WARNINGS ISSUED YDY. THE CFW HAS
THE ANTICIPATED CONCERNS.
AT 6AM...BOSTON IS RUNNING .08 ABV PREDICTED DEPARTURE
NANTUCKET IS SPOT ON THE GLIDE SLOPE
PVD-FOX POINT IS RUNNING CLOSE AS WELL.
THE 00Z/GFS SURGE GUIDANCE WAS MODIFIED UP 1 FT THRU 00Z/TUE...WHICH
I THINK IS IN PART RESPONSIBLE FOR THE MAJOR FLOOD POTENTIAL OUTLOOK
FOR SCITUATE. CONFIDENCE ON SCITUATE REACHING MAJOR FLOOD THRESHOLD
IS LOW.
NO CHANGE TO THE 00Z/14 SURGE GUIDANCE WAS APPLIED TO NANTUCKET OR
CHATHAM AREA AS GUIDANCE WAS VERIFYING.
I DID RAISE UPPER NARR AND BUZZ BAYS BY 0.8 FT THRU 00Z TUE AND THAT
MAY BE IN ERROR. AM NOT EXPECTING ANY SIGNIFICANT FLOODING THERE.
WE EXPECT WIDESPREAD MINOR WITH POCKETS OF MODERATE COASTAL FLOODING
AT THE TIME OF THE NEXT 4 HIGH TIDE CYCLES IN EASTERN MASS
COAST...SCITUATE NORTHWARD.
BEACH EROSION THROUGH AT LEAST TUESDAY MORNING.
&&
.CLIMATE...
DAILY RECORDS FOR 3/14/10
BOS 1.93 1958
PVD 1.28 1980 AND PREV
ORH 1.39 1986
BDL 1.35 1986
IF BOSTON RECEIVES 3 INCHES IN 1 DAY...THIS WILL BE THE FIRST TIME
SINCE MAY 2006. SINCE WE HAD SO MUCH PRIOR TO MIDNIGHT...3 INCHES
TODAY IN BOSTON DOES NOT APPEAR LIKELY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH MONDAY MORNING FOR CTZ002>004.
WIND ADVISORY UNTIL 8 AM EDT THIS MORNING FOR CTZ002>004.
MA...FLOOD WATCH THROUGH MONDAY MORNING FOR MAZ002>021-026.
WIND ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MAZ002>005-
008>013-026.
HIGH WIND WARNING UNTIL 8 AM EDT THIS MORNING FOR MAZ006-007-
014>024.
COASTAL FLOOD WARNING FROM 10 AM THIS MORNING TO 3 PM EDT THIS
AFTERNOON FOR MAZ007-015-016-019.
COASTAL FLOOD WATCH FROM THIS EVENING THROUGH LATE TONIGHT FOR
MAZ007-015-016-019-022-024.
NH...FLOOD WATCH THROUGH MONDAY MORNING FOR NHZ011-012-015.
WIND ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NHZ011-012-015.
RI...FLOOD WATCH THROUGH MONDAY MORNING FOR RIZ001>008.
WIND ADVISORY UNTIL 8 AM EDT THIS MORNING FOR RIZ001>004.
HIGH WIND WARNING UNTIL 8 AM EDT THIS MORNING FOR RIZ005>008.
MARINE...STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR ANZ232>237-255-
256.
STORM WARNING UNTIL 3 PM EDT THIS AFTERNOON FOR ANZ230-231-250-
251-254.
&&
$$
SYNOPSIS...DRAG/STRAUSS
NEAR TERM...STRAUSS
SHORT TERM...STRAUSS
LONG TERM...DRAG/EKSTER
AVIATION...DRAG/STRAUSS
MARINE...DRAG/STRAUSS
HYDROLOGY...
TIDES/COASTAL FLOODING...
CLIMATE...
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