Area Forecast Discussion
Issued by NWS Boston, MA

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000
FXUS61 KBOX 311730
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
130 PM EDT FRI OCT 31 2014

.SYNOPSIS...
DRY AND SEASONABLE CONDITIONS WILL CONTINUE TODAY AS HIGH PRESSURE
MOVES ACROSS NORTHERN NEW ENGLAND. A DEVELOPING COASTAL STORM
WILL MOVE UP THE COAST SATURDAY AND PASS OFFSHORE SATURDAY NIGHT
AND EARLY SUNDAY BRINGING HIGH WINDS AND RAIN TO THE REGION. HIGH
PRESSURE BUILDS OVER THE EASTERN U.S. FOR EARLY NEXT WEEK. ONE OR
TWO COLD FRONTS MAY CROSS SOUTHERN NEW ENGLAND WEDNESDAY AND
THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
130 PM UPDATE...DID NOT MAKE ANY MAJOR CHANGES TO THE FORECAST AT
THIS TIME. UPDATED WINDS AND POPS THROUGH THE PERIOD BUT DID NOT
STRAY FAR FROM THE MORNING UPDATE...ONLY INCORPORATED NEW GUIDANCE
WHICH IS ON TRACK WITH EARLIER GUIDANCE. WILL BE LOOKING CLOSER AT
TEMPERATURES AND WEATHER /ANY P-TYPE ISSUES/ FOR THE REMAINDER OF
THE AFTERNOON. CURRENT WEATHER IS ON TRACK WITH TEMPERATURES IN
THE UPPER 40S TO LOW 50S AS OF 1 PM.

***UPDATES MADE TO WEEKEND STORM***

1015 AM UPDATE...BASED ON LATEST MODEL GUIDANCE HAVE INCREASED
WINDS FOR THE SATURDAY TO SUNDAY TIME PERIOD. WHILE THERE IS STILL
A BIT OF UNCERTAINTY ON THE TRACK OF THE COASTAL LOW...BELIEVE IT
WILL BE CLOSE ENOUGH TO SOUTHERN NEW ENGLAND TO RESULT IN VERY
GUSTY TO POSSIBLY DAMAGING WINDS FOR AT LEAST A PORTION OF THE
REGION. THE HIGHEST CONFIDENCE FOR HIGH WINDS TO OCCUR IS OVER THE
CAPE AND ISLANDS SATURDAY NIGHT AND SUNDAY. HOWEVER...WITH THE 06Z
GFS BRINGING THE LOW A BIT CLOSER TO SOUTHERN NEW ENGLAND...HAVE
ISSUED A HIGH WIND WATCH FOR ALL OF EASTERN MASSACHUSETTS AND
RHODE ISLAND.

OVERALL...THE FORECAST FOR TODAY IS ON TRACK...NO CHANGES WERE
MADE TO THE FORECAST FOR TODAY.

745 AM UPDATE...

ONLY MINOR TWEAKS TO THE FORECAST THIS MORNING.

PREVIOUS DISCUSSION...

AREA OF LOW TO MID LEVEL CLOUDS REMAIN ACROSS CENTRAL AND EASTERN
AREAS AT 07Z...THOUGH NOTING SOME CLEARING ACROSS THE CT VALLEY AS
WELL AS ALONG THE S COAST ON LATEST IR SATELLITE LOOP. NAM AND GFS
BUFKIT SOUNDINGS INDICATING THAT THE 5-6KFT CEILINGS MAY BREAK UP
BRIEFLY AROUND MID TO LATE MORNING BEFORE REDEVELOPING AS NE WINDS
BRING IN INCREASING LOW LEVEL MOISTURE DURING THE AFTERNOON...
AGAIN ACROSS CENTRAL AND EASTERN AREAS.

LOW PRES MOVES SE OUT OF THE GREAT LAKES...THEN SECONDARY
DEVELOPMENT BEGINS OFF THE MID ATLC COAST. LOOKS LIKE MOST OF THE
DEEP MOISTURE WITH THE CYCLOGENESIS WILL REMAIN S OF THE REGION SO
HAVE KEPT A DRY FORECAST GOING. MAY SEE SOME SPRINKLES AND PATCHY
DRIZZLE DEVELOP LATE IN THE DAY ALONG THE E COAST...BUT NOT ENOUGH
TO MENTION AT THIS POINT.

EXPECT TEMPS TO ONLY RISE TO THE UPPER 40S ACROSS THE HIGHER
INLAND TERRAIN...THEN MAINLY IN THE 50S ELSEWHERE WITH THE
FRESHENING E-NE WINDS ESPECIALLY DURING THE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
TONIGHT...SHORT RANGE MODELS APPEAR TO BE IN BETTER AGREEMENT IN
THE DEVELOPMENT OF NOT ONE BUT TWO CENTERS OF LOW PRES AS H5 LONG
WAVE TROUGH DIGS ACROSS THE SE U.S. NOTING TWO STRONG UPPER LEVEL
JETS MOVING AROUND THE BASE OF THIS DIGGING TROUGH...THE FIRST
90-100 KT H3 JET AXIS WORKS NE OVERNIGHT. THIS WILL HELP
INTENSIFY THE FIRST LOW OFF THE MID ATLC COAST AROUND 12Z SAT.

AREA OF RAIN WILL WORK STEADILY NORTHWARD...ESPECIALLY AROUND OR
AFTER MIDNIGHT. WILL ALSO SEE NE WINDS INCREASE ALONG THE COAST
WITH GUSTS UP TO 25-30 KT...HIGHEST ALONG THE S COAST...CAPE COD
AND THE ISLANDS. BEST SHOT FOR PRECIP WILL BE ACROSS RI/E MA.

EXPECT OVERNIGHT LOWS TO RANGE FROM THE UPPER 30S OVER SW NH TO
BETWEEN 45 AND 50 ALONG THE COAST.

&&

.LONG TERM /SATURDAY THROUGH FRIDAY/...
BIG PICTURE...
DEEP AMPLITUDE TROUGHS ON BOTH COASTS SATURDAY WITH A RIDGE IN
BETWEEN. SHORTWAVE MOVING THROUGH THE EASTERN TROUGH GENERATES A
CUTOFF UPPER LOW WITH TWO JET STREAMS...A NORTHERN STREAM ALONG
THE CANADIAN BORDER AND A SOUTHERN STREAM MOVING WITH THE SHORT
WAVE. THE PATTERN SHIFTS EAST DURING THE WEEK WITH THE RIDGE
BUILDING OVER NEW ENGLAND. THE PATTERN THEN TRANSFORMS TO A MORE
ZONAL FLOW. REMAINS OF THE PACIFIC COAST TROUGH MOVE ACROSS NEW
ENGLAND MIDWEEK.

COLDER THAN NORMAL HEIGHTS WITH THE EASTERN TROUGH THIS WEEKEND.
HEIGHTS INCREASE TO NORMAL OR A LITTLE ABOVE NORMAL BY MIDWEEK.
THIS POINTS TO A COLDER THAN NORMAL WEEKEND...TRENDING TO NORMAL
TEMPERATURES BY MIDWEEK.

31/00Z GUIDANCE SUITE REMAINS IN DECENT OVERALL AGREEMENT. THERE
ALSO REMAIN SOME DIFFERENCES WITH TRACK...INTENSITY AND TIMING. AT
THIS POINT IT APPEARS SNOWFALL IS MOSTLY OFF THE TABLE AWAY FROM A
VERY BRIEF PERIOD LATE SATURDAY NIGHT ACROSS THE HIGHER TERRAIN.
EVEN THEN...IT WILL NOT AMOUNT TO MUCH. FAVORED A BLEND TO SMOOTH
OVER SOME OF THE MORE MINOR DIFFERENCES. THIS RESULTED IN VERY
GOOD CONTINUITY WITH THE PREVIOUS FORECAST.

THE DAILIES...

SATURDAY-SUNDAY...
COASTAL STORM CONTINUES TO BE INDICATED FOR SATURDAY AND EARLY
SUNDAY. SUPPORT COMES FROM TWO SETS OF FORCING MECHANISMS...
SUGGESTING A TWO-PART EVENT. INITIAL FORCING COMES FROM RIGHT
ENTRANCE REGION OF NORTHERN STREAM JET SATURDAY MORNING. THIS WILL
SEND A COASTAL WAVE OF LOW PRESSURE PAST SOUTHERN NEW ENGLAND
DURING THE DAY SATURDAY.

THE SECOND FORCING COMES FROM LEFT EXIT REGION OF JET SUPPORTING
A POTENT SHORTWAVE ROUNDING THE BASE OF THE EASTERN TROUGH LATE
SATURDAY/SATURDAY NIGHT. EVEN SO...MOST OF THE FRONTOGENETIC
FORCING WITH EACH SEGMENT IS FOCUSED OFFSHORE INTO THE MARITIMES
AND MAINE. THE WESTERN EDGE OF THIS FORCING SHOULD EXTEND INTO
SOUTHERN NEW ENGLAND WITH THE FIRST...AND POSSIBLY THE SECOND...OF
THE SEGMENTS. WE EXPECT RAIN SATURDAY AND SATURDAY NIGHT WITH
HIGHEST POPS OVER CAPE COD AND THE ISLANDS...LESSER VALUES NORTH
AND WEST.

STRONG PRESSURE GRADIENT AT THE SURFACE AND A 50 KNOT LOW LEVEL
JET WILL CONTRIBUTE TO WINDY CONDITIONS. THE STRONGEST WINDS WILL
BE OVER THE EASTERN/SOUTHEAST WATERS. STRONGEST LAND WINDS WILL BE
OVER THE OUTER CAPE AND ISLANDS...DIMINISHING FARTHER WEST. HAVE
FEATURED 45 KNOTS FOR THE STRONGEST WINDS AND 20-25 KNOTS IN THE
INTERIOR.

A COASTAL STORM WILL PASS US IN PIECES SATURDAY AND LATER
SATURDAY NIGHT...AS NOTED ABOVE. EXPECT PRECIPITATION TO DIMINISH
WEST TO EAST AFTER MIDNIGHT AND END ON THE MA EAST COAST AFTER
SUNRISE SUNDAY MORNING.

TEMPERATURES THROUGH MOST OF THIS STORM SHOULD REMAIN FAVORABLE
FOR ALL RAIN. AS THE WINDS SHIFT FROM NORTHEAST TO NORTHWEST
SATURDAY NIGHT...COLDER AIR WILL BE DRAWN IN WHICH COULD CHANGE
THE LAST SHOWERS OVER TO SNOW ACROSS THE HIGHER TERRAIN. ANY
ACCUMULATIONS SHOULD NOT BE MUCH MORE THAN A TRACE...WHERE IT
SNOWS AT ALL.

DRIER AIR SUNDAY WILL BRING CLEARING SKIES. COLD ADVECTION WILL
PROMOTE MIXING THROUGH AT LEAST 850 MB. WINDS IN THIS LAYER WILL
BE 35 TO 40 KNOTS...SO EXPECT NORTHWEST GUSTS TO AT LEAST THE
LOWER END OF THIS RANGE. WINDS DIMINISH SUNDAY NIGHT AS THE STORM
MOVES FARTHER AWAY.

MONDAY-TUESDAY...
HIGH PRESSURE BUILDS OVER THE REGION. MONDAY SHOULD BE SUNNY AS
THIS HIGH MOVES OVERHEAD. MIXING WILL AGAIN BRING INCREASED WIND
GUSTS DURING THE AFTERNOON. WINDS IN THE MIXED LAYER ARE EXPECTED
AROUND 30 KNOTS WITH POTENTIAL FOR A LITTLE STRONGER SPEEDS. WINDS
WILL DIMINISH WITH SUNSET.

THIS HIGH PRESSURE MOVES OFFSHORE TUESDAY. THIS WILL MAKE ROOM
FOR A WARM FRONT TO SWING PAST. SUFFICIENT LIFT AND MOISTURE TO
SUPPORT MID AND HIGH CLOUDS...BUT THE BEST WARM FRONTAL LIFT WILL
REMAIN TO OUR NORTH AND WEST SO EXPECT AT LEAST SOME SUN THROUGH
THE DAY.

WEDNESDAY-THURSDAY...
LOW CONFIDENCE ON MIDWEEK WEATHER. AT LEAST ONE TROUGH IN THE
ZONAL FLOW WILL SWING ACROSS THE REGION DURING THIS TIME. GFS AND
ECMWF ARE HINTING AT ONE ON WEDNESDAY...BUT SHOWING A MORE
SUBSTANTIAL TROUGH PASSING ON THURSDAY. THE FORECAST WILL HAVE
CLOUDS AND LOW-END CHANCE OR SLIGHT CHANCE POPS.

&&

.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...HIGH CONFIDENCE. VFR. THERE ARE A FEW LOCATIONS ON
THE CAPE AND ISLANDS THAT ARE HAVING PATCHY MVFR CIGS.

TONIGHT...MODERATE CONFIDENCE. CONDITIONS DETERIORATE THROUGH THE
NIGHT TO MVFR-IFR FROM SOUTH TO NORTH WITH LOWEST CONDITIONS ALONG
THE COAST. EXPECT SCATTERED SHOWERS SOUTH OF THE MASS PIKE WITH
THE GREATEST CHANCE OF STEADIER RAINFALL ALONG THE SOUTH COAST.

SATURDAY THROUGH SUNDAY...MODERATE TO HIGH CONFIDENCE. MVFR/IFR
CONDITIONS CONTINUE THROUGH 12Z SUNDAY WHEN CEILINGS START TO RISE
FROM WEST TO EAST AS LOW PRESSURE PULLS AWAY FROM SOUTHERN NEW
ENGLAND. NORTHEASTERLY WINDS INCREASE THROUGH THE PERIOD...PEAKING
IN THE 40 TO 50 KT RANGE SATURDAY NIGHT INTO SUNDAY MORNING FOR
THE EASTERN TERMINALS. WINDSPEEDS WILL BE LOWER ACROSS THE WESTERN
TERMINALS BUT STILL GUSTING UP TO 35 TO 45 KTS PEAKING MORE ON
SUNDAY. WIDESPREAD RAIN EXPECTED THROUGH SUNDAY MORNING MOST
LOCATIONS AND CONTINUING ON THE EAST COAST...CAPE...AND ISLANDS
INTO SUNDAY AFTERNOON.

KBOS...HIGH CONFIDENCE IN TAF TRENDS. LOWER CONFIDENCE ON EXACT
TIMING OF ONSET OF RAIN AND HIGHER WINDS.

KBDL...HIGH CONFIDENCE IN TAF TRENDS. LOWER CONFIDENCE ON EXACT
TIMING OF ONSET OF RAIN AND HIGHER WINDS.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...MODERATE CONFIDENCE.

MONDAY...VFR. DAYTIME WIND GUSTS WILL INCREASE TO NEAR 30 KNOTS
INLAND AND 35 KNOTS CAPE AND ISLANDS...DIMINISHING TOWARD EVENING.

TUESDAY AND WEDNESDAY...VFR WITH INCREASING HIGH CLOUDS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH TONIGHT/...HIGH CONFIDENCE.

TODAY...WINDS AND SEAS REMAIN BELOW SMALL CRAFT CRITERIA. WINDS
WILL VEER TO E-NE DURING THE DAY AND BEGIN TO PICK UP. GUSTS UP TO
20 KT REACH THE SOUTHERN OUTER WATERS BY LATE IN THE DAY. SEAS
REMAIN BELOW 5 FT.

TONIGHT...E-NE WINDS INCREASE WITH GUSTS UP TO 25-30 KT. SMALL
CRAFTS REMAIN IN EFFECT FOR MOST OF THE WATERS...BUT NOT QUITE
THERE FOR BOSTON HARBOR AND MASS/IPSWICH BAYS. SEAS WILL ALSO
BUILD ESPECIALLY ON THE SOUTHERN OPEN WATERS DURING THE NIGHT.

OUTLOOK...SATURDAY THROUGH TUESDAY...MODERATE CONFIDENCE.

***STORM WATCH ISSUED FOR ALL THE COASTAL WATERS FOR SATURDAY
 AFTERNOON THROUGH SUNDAY MORNING***

1015 AM UPDATE...GIVEN THE LATEST FORECAST GUIDANCE...HAVE
INCREASED THE WINDS QUITE A BIT OVER THE COASTAL WATERS. LOOKS TO
BE A HIGH LIKELIHOOD OF NORTHEASTERLY STORM FORCE
GUSTS...PARTICULARLY OVER THE EASTERN WATERS. DEPENDING ON THE
EXACT TRACK OF THE LOW...COULD SEE STORM FORCE GUSTS AS FAR WEST
AS THE WATERS SOUTH OF RHODE ISLAND.

SUNDAY...RAIN MOVES OFF TO THE EAST. WINDS SHIFT NORTHWEST.
EXPECTING THESE WINDS TO DIMINISH BELOW GALE FORCE SUNDAY NIGHT.
WITH THE WIND SHIFT...ROUGH SEAS WILL TRANSITION FARTHER OFFSHORE
WITH DIMINISHING SEAS CLOSER TO SHORE. GALE WARNINGS WILL LIKELY
LINGER INTO THE EVENING HOURS.

MONDAY...GUSTY NORTHWEST WINDS WITH WIND GUSTS APPROACHING GALE
FORCE AGAIN DURING THE DAY. WINDS DIMINISH TOWARD EVENING. SEAS
WILL LINGER AT 5-9 FEET...ESPECIALLY ON THE OUTER WATERS. SMALL
CRAFT ADVISORY IS LIKELY...LOW END CHANCE THAT GALES MAY BE NEEDED
ON SOME OF THE WATERS.

TUESDAY...WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS.

&&

.TIDES/COASTAL FLOODING...
1015 AM UPDATE...A COASTAL FLOOD WATCH WAS ISSUED FOR THE SATURDAY
EVENING AND EARLY SUNDAY MORNING HIGH TIDE CYCLES FOR THE EASTERN
MA COAST...INCLUDING THE NORTH FACING PORTION OF CAPE COD AND
NANTUCKET. THIS IS FOR THE POTENTIAL OF MINOR TO ISOLATED POCKETS
OF MODERATE COASTAL FLOODING POSSIBLE ALONG WITH BEACH EROSION.

ASTRONOMICAL HIGH TIDES ARE RATHER LOW SATURDAY EVENING AND AGAIN
EARLY SUNDAY MORNING. HOWEVER...STRONG NORTH TO NORTHEAST WIND GUSTS
UP TO 50 KNOTS MAY RESULT IN SEAS BUILDING TO AROUND 20 FEET OVER
THE OPEN WATERS.  STILL SOME UNCERTAINTY AS TO HOW STRONG THE WINDS
WILL GET...GIVEN MODEL SPREAD.  HOWEVER...THERE CERTAINLY IS THE
POTENTIAL FOR A 2 TO 2.5 STORM SURGE TO COMBINED WITH SIGNIFICANT
WAVE ACTION.  THIS WILL RESULT IN MINOR COASTAL FLOODING WITH
PERHAPS ISOLATED POCKETS OF MODERATE COASTAL FLOODING.
THEREFORE...WE FELT IT WAS WORTH AT LEAST A WATCH AT THIS TIME.

THE HIGHEST RISK AREAS APPEAR TO BE HULL AND SCITUATE.  WE ALSO HAVE
TO BE CONCERNED WITH THE TYPICAL HOT SPOTS...SUCH AS SALISBURY AND
PLUM ISLAND WHICH ARE VERY SUSCEPTIBLE TO BEACH EROSION.  WILL ALSO
HAVE TO KEEP AN EYE ON NANTUCKET HARBOR...AS STRONG NORTHERLY WINDS
CAN CAUSE ISSUES FOR THEM.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING
     FOR MAZ005>007-013>021.
     COASTAL FLOOD WATCH FROM SATURDAY EVENING THROUGH SUNDAY
     MORNING FOR MAZ007-015-016-019-022-024.
     HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
     AFTERNOON FOR MAZ022>024.
NH...NONE.
RI...HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING
     FOR RIZ001>008.
MARINE...STORM WATCH FROM SATURDAY MORNING THROUGH SUNDAY AFTERNOON FOR
     ANZ230>237-250-251-254>256.

&&

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



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