Area Forecast Discussion
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000
FXUS61 KBOX 301355
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
955 AM EDT THU OCT 30 2014

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND SEASONABLE CONDITIONS THROUGH
THE END OF THE WORK WEEK. A COASTAL STORM WILL LIKELY DELIVER A
GLANCING BLOW TO THE REGION LATE SATURDAY INTO SUNDAY...BUT THE
OPPORTUNITY FOR A HIGHER IMPACT STILL EXISTS. MAINLY DRY WEATHER
FOLLOWS WITH A SIGNIFICANT WARMING TREND BY NEXT TUESDAY AND
WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...MADE SOME CHANGES TO THE SKY FORECAST BASED ON THE
LATEST SATELLITE IMAGERY.  OTHERWISE...FORECAST IS ON TRACK.

PREVIOUS DISCUSSION...

FOR TODAY...EXPECT DRY CONDITIONS AS WEAK HIGH PRES APPROACHES
FROM THE WEST DURING THE DAY AS H5 SHORT WAVE CROSSES THE
REGION...PUSHING OFFSHORE BY MIDDAY. H85 TEMPS DO FALL DURING THE
DAY...THOUGH LOOKS LIKE THE CORE OF THE COLD AIR REMAINS TO THE N.
TEMPS WILL BE SEASONABLE FOR LATE OCTOBER...TOPPING OFF IN THE
50S. EXPECT LIGHT W-NW WINDS WITH A LIGHT PRES GRADIENT ACROSS THE
REGION.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
TONIGHT...
EXPECT THE WEAK HIGH PRES RIDGE TO BUILD E ACROSS NORTHERN NEW
ENGLAND TONIGHT. LIGHT N WINDS WILL BE IN PLACE WHICH WILL VEER TO
NE AFTER MIDNIGHT. MAY SEE SOME MORE PATCHY FOG DEVELOP IN THE
NORMALLY PRONE VALLEY AREAS.

NOTING LOW PRES OVER THE GREAT LAKES TONIGHT AS A DIGGING H5
SHORT WAVE DIVES SE. SW FLOW ALOFT REMAINS IN PLACE...SO COULD
SEE SOME MID AND HIGH CLOUDS WORK INTO WESTERN AREAS AFTER
MIDNIGHT. WITH THE COLDER AIR WORKING IN ALONG WITH A GENERAL
LIGHT WIND IN PLACE...EXPECT LOWS FALLING BACK TO THE 30S FOR MOST
AREAS...RANGING TO LOWER-MID 40S ALONG THE IMMEDIATE COAST. WILL
NEED TO MONITOR FOR FROST/FREEZE HEADLINES MAY BE NECESSARY FOR
S/E COASTAL MA AND RI.

FRIDAY...
MAJOR DIGGING H5 LONG WAVE TROUGH/CUTOFF LOW TAKES SHAPE ACROSS
THE OHIO VALLEY INTO THE CENTRAL GREAT LAKES...WHICH SETS UP AN
INCREASING SW FLOW ALOFT ALONG THE EASTERN SEABOARD. HOWEVER...AT
THE SURFACE...GENERAL LIGHT FLOW CONTINUES THOUGH E-NE WINDS WILL
BEGIN TO FRESHEN DURING THE AFTERNOON ALONG THE S COAST. BIG
QUESTION AT THIS POINT...WHERE LOW PRES DEVELOPS OFF THE MID ATLC
OR SE U.S. COAST FRI AFTERNOON.

EXPECT CLOUDS TO INCREASE WITH THE INCREASING LOW LEVEL ONSHORE
FLOW IN PLACE. THIS WILL HOLD TEMPS BACK. HIGHS WILL ONLY REACH
THE UPPER 40S ACROSS THE HIGHER TERRAIN OF SW NH/W MA...RANGING TO
THE LOWER-MID 50S ELSEWHERE.

AT THIS POINT...NOT EXPECTING ORGANIZED PRECIP DURING THE DAY ON
FRIDAY AS BEST LIFT AND MOISTURE REMAINS S OF THE REGION.
HOWEVER...COULD SEE SOME OCEAN INDUCED LIGHT SPRINKLES OR EVEN
SOME COASTAL DRIZZLE. DID NOT MENTION THIS FOR NOW.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
HIGHLIGHTS...

* GLANCING BLOW MOST LIKELY SAT/EARLY SUNDAY...BUT GREATER IMPACT
  STILL POSSIBLE
* BIGGEST CONCERN IS STRONG WINDS THIS WEEKEND ESPECIALLY CAPE COD
* ACCUMULATING SNOW IS STILL POSSIBLE...BUT A LOW PROBABILITY
* MUCH MILDER WEATHER RETURNS BY NEXT TUESDAY AND WEDNESDAY

OVERVIEW...30/00Z GUIDANCE HAD COME INTO BETTER AGREEMENT
REGARDING THEIR HANDLING OF A SIGNIFICANT COASTAL STORM THIS
WEEKEND. THERE ARE A FEW ENSEMBLE MEMBERS THAT SUGGEST A CLOSER
TRACK TO SOUTHERN NEW ENGLAND REMAINS POSSIBLE...BUT NOT VERY
LIKELY. THE PREDOMINANT SIGNAL IS FOR A TRACK REMAINING SOUTH AND
EAST OF THE 40N/70W BENCHMARK. WILL FAVOR A CONSENSUS BLEND TO
SMOOTH OVER AS MANY MINOR DIFFERENCES AS POSSIBLE.

DETAILS...

SATURDAY AND SUNDAY...
FORECAST CONFIDENCE IN THE DETAILS REMAINS MODERATE FOR THIS TIME
PERIOD. THE BIGGEST CONCERN REMAIN POTENTIAL FOR STRONG TO PERHAPS
DAMAGING WINDS...ESPECIALLY ACROSS THE CAPE AND NANTUCKET. THERE
ARE TWO MAIN SHORTWAVES INVOLVED IN THIS STORM/S FORMATION.
INITIALLY...MOST MODELS FORM AN ELONGATED LOW PRESSURE SYSTEM OR
EVEN TWO CENTERS BEFORE CONSOLIDATING INTO A SINGLE PRIMARY STORM.
CURRENT INDICATIONS ARE THAT THIS HAPPENS TOO LATE FOR A
SIGNIFICANT RAIN/SNOW EVENT IN SOUTHERN NEW ENGLAND.

PRECIPITATION TYPE AND TIMING...A LOT OF THIS WILL DEPEND ON HOW
FAR WEST THE MAIN PRECIPITATION SHIELD REACHES. MOST OF THE
FRONTOGENETICAL FORCING IS EXPECTED TO REMAIN OFFSHORE...WHICH
WOULD ALSO SUGGEST A RATHER SHARP WESTERN EDGE TO THE
PRECIPITATION SHIELD. MINOR WOBBLES IN THE TRACK...COULD HAVE A
SIGNIFICANT IMPACT ON WHERE THIS EDGE TO THE PRECIPITATION
ESTABLISHES ITSELF.

INITIALLY...ALL PRECIPITATION WILL BE IN THE FORM OF RAIN OR JUST
SCATTERED SHOWERS SATURDAY. IN FACT...MOST OF THE PRECIPITATION WILL
BE OVER EASTERN NEW ENGLAND...WITH JUST A FEW SHOWERS ACROSS WESTERN
SECTIONS IF THE CURRENT TRACK VERIFIES. IF THIS TRACK SHIFTS WEST
AND WE END UP GETTING INTO HEAVIER PRECIPITATION SATURDAY NIGHT AND
EARLY SUNDAY...DYNAMIC COOLING COULD RESULT IN SOME SNOW ACROSS THE
HIGHER TERRAIN. AGAIN...BASED ON THE CURRENTLY EXPECTED TRACK...ACCUMULATING
SNOW IS A RATHER LOW PROBABILITY. REGARDLESS...MOST PRECIPITATION
SHOULD HAVE EXITED OUR REGION BY MID MORNING SUNDAY.

STRONG WINDS...
STRONG WINDS ARE THE ONE THING WE ARE FAIRLY CONFIDENT THAT WILL
DEVELOP. EXCELLENT MIXING ON THE BACKSIDE OF THIS STORM SHOULD
RESULT IN NORTH TO NORTHWEST WIND GUSTS OF 40 TO 50 MPH DEVELOPING
LATE SATURDAY AND ESPECIALLY SUNDAY AS MIXING INCREASES. ACROSS
CAPE COD AND NANTUCKET...DEPENDING ON THE TRACK OF THIS STORM...WE
MAY SEE A PERIOD OF 50 TO 60 MPH WIND GUSTS. WIND ADVISORIES MAY
BE NEEDED FOR MUCH OF THE REGION AND PERHAPS HIGH WIND
WATCHES/WARNINGS FOR THE CAPE AND NANTUCKET. GIVEN MANY TREES
STILL HAVE AT LEAST SOME LEAVES ON THEM...THE RISK FOR TREE DAMAGE
AND ISOLATED POWER OUTAGES WILL BE ENHANCED.

MONDAY THROUGH WEDNESDAY...
DEEP UPPER TROUGH LIFTS NORTHEAST OF THE REGION AND WE ENTER AN
AREA OF UPPER LEVEL RIDGING. A SIGNIFICANT WARMING TREND EXPECTED
WITH SOME OF THE COASTAL PLAIN POSSIBLY SEEING HIGHS BREAK 60 BY
TUESDAY OR WEDNESDAY. MAINLY DRY WEATHER OVER THIS TIME...BUT A
SPOT SHOWER OR TWO IS POSSIBLE...ESPECIALLY TOWARD WEDNESDAY.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH FRIDAY/...HIGH CONFIDENCE THROUGH
TONIGHT...THEN MODERATE CONFIDENCE FRIDAY.

TODAY...VFR. SCT-BKN CLOUDS 4-5KFT THROUGH THIS AFTERNOON.

TONIGHT...VFR. INCREASING CLOUDS AFTER MIDNIGHT. MAY SEE LOCAL
MVFR-IFR ACROSS SW NH INTO NW MA LATE. SHALLOW PATCHY GROUND FOG
POSSIBLE AT PRONE TERMINALS.

FRIDAY...MAINLY VFR. WINDS SHIFT TO E-NE DURING DAY...INCREASING
ALONG COAST TO 10-15 KT WITH SOME GUSTS TO 20 KT LATE IN DAY.
MAY SEE MVFR CIGS DEVELOP ALONG E COAST TERMINALS DURING THE
AFTERNOON. WIDELY SCT SHOWERS ALONG S COAST POSSIBLE LATE.

KBOS...HIGH CONFIDENCE IN TAF.

KBDL...HIGH CONFIDENCE IN TAF.

OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...

FRIDAY NIGHT...MODERATE CONFIDENCE. VFR TO START BUT ONSHORE FLOW
MAY RESULT IN MVFR CIGS DEVELOPING. A SPOT SHOWER OR TWO POSSIBLE.

SATURDAY AND SUNDAY...MODERATE CONFIDENCE. STILL SOME UNCERTAINTY
WITH THE TRACK OF A LOW PRESSURE. MOST LIKELY SCENARIO IS VFR TO
BE MIXED AT TIMES WITH MVFR LATE SATURDAY INTO SATURDAY NIGHT.
LOWER CONDITIONS MOST LIKELY ALONG THE COAST WITH RAIN OR
SCATTERED SHOWERS.

LOW PROBABILITY FOR A CHANGE TO SNOW AT THE END. CONDITIONS
IMPROVE TO VFR BY LATE SUNDAY...BUT NORTH TO NORTHWEST WIND GUSTS
OF 30 TO 40 KNOTS EXPECTED. STRONGEST WINDS ACROSS CAPE COD AND
NANTUCKET WITH GUSTS OF 40 TO 50 KNOTS POSSIBLE.

MONDAY...HIGH CONFIDENCE. VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH FRIDAY/...HIGH CONFIDENCE.

TODAY...SEAS WILL CONTINUE TO SUBSIDE ACROSS THE OUTER WATERS E
AND S OF CAPE COD THIS MORNING. EXPECTING WINDS AND SEAS BELOW
SMALL CRAFT CRITERIA.

TONIGHT...LIGHT NE WINDS AND SEAS UP TO 3 FT.

FRIDAY...WINDS BECOME E-NE BUT WILL REMAIN BELOW SMALL CRAFT
CRITERIA. SEAS SLOWLY INCREASE TO 3 FT ON SOUTHERN OUTER WATERS.

OUTLOOK...FRIDAY NIGHT THOUGH MONDAY...

***STORM FORCE WIND GUSTS AND 20 FOOT SEAS POSSIBLE LATE SATURDAY
 INTO SUNDAY ACROSS THE OPEN ATLANTIC WATERS EAST OF
 MASSACHUSETTS***

FRIDAY NIGHT...HIGH CONFIDENCE. INCREASING NE WINDS. GUSTS UP TO
30 KT WITH SEAS BUILDING TO AROUND 5 FT ON THE OUTER WATERS.

SATURDAY AND SUNDAY...MODERATE CONFIDENCE. HIGH IMPACT MARINE
EVENT EXPECTED. WHILE UNCERTAINTY REMAINS ON THE EXACT TRACK AND
TIMING OF A COASTAL LOW PRESSURE...HIGH CONFIDENCE GALE FORCE
NORTHERLY WIND GUSTS ACROSS MOST WATERS LATE SATURDAY INTO SUNDAY.
IN FACT...MODERATE RISK FOR A PERIOD OF STORM FORCE WIND GUSTS
WITH 20 FOOT SEAS ACROSS THE OPEN ATLANTIC WATERS EAST OF
MASSACHUSETTS. EXACT WIND SPEEDS AND WAVE HEIGHTS WILL DEPEND UPON
THE EXACT TRACK AND INTENSITY OF COASTAL LOW PRESSURE. A MARINE
WEATHER STATEMENT WAS ISSUED TO ADDRESS THESE CONCERNS.

MONDAY...MODERATE CONFIDENCE. NORTHWEST 25-30 KT WIND GUSTS AND
SEAS WILL LIKELY CONTINUE MUCH OF THE DAY WITH GOOD MIXING IN THE
COLD AIR ADVECTION PATTERN.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL HIGH TIDES ARE NOT THAT IMPRESSIVE LATE SATURDAY
INTO SUNDAY. NONETHELESS...THERE IS AT LEAST A LOW PROBABILITY FOR
MINOR COASTAL FLOODING/EROSION ALONG THE EASTERN MA COAST AS WELL
AS PORTIONS OF CAPE COD AND NANTUCKET. THE CONCERN IS FOR THE
EARLY MORNING HIGH TIDE SUNDAY. IF WE END UP REALIZING 20 FOOT
SEAS OVER THE OPEN OCEAN AND NORTHERLY WIND GUSTS OF 40 TO 50
KNOTS...THERE COULD BE SOME MINOR COASTAL FLOODING AND EROSION.
SOME OF THE HOT SPOTS WOULD BE SALISBURY AND PLUM ISLAND...
HULL...SCITUATE AND PERHAPS SANDWICH HARBOR AND NANTUCKET HARBOR.
AGAIN...IT WILL DEPEND ON EXACT WIND SPEEDS/WAVE HEIGHTS OUT OVER
THE OCEAN DURING THE EARLY MORNING SUNDAY HIGH TIDE CYCLE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/EVT
NEAR TERM...BELK/RLG/EVT
SHORT TERM...EVT
LONG TERM...FRANK
AVIATION...FRANK/EVT
MARINE...FRANK/EVT
TIDES/COASTAL FLOODING...



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