Area Forecast Discussion
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FXUS61 KBOX 062000
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
400 PM EDT FRI MAY 6 2016

.SYNOPSIS...
LOW PRESSURE OVER THE MID ATLC REGION WILL WEAKEN SATURDAY AS IT
MOVES SOUTH OF NEW ENGLAND. A COLD FRONT WITH A BAND OF SCATTERED
SHOWERS LIKELY CROSSES THE REGION SUNDAY MORNING FOLLOWED BY A
DRY...MILD BUT WINDY AFTERNOON. MUCH OF NEXT WEEK LOOKS SEASONABLE
WITH MILD AFTERNOON/S. THERE STILL REMAINS THE LOW RISK FOR A
PERIOD OF COOL AND WET WEATHER SOMETIME TUESDAY INTO
WEDNESDAY...BUT THE LATEST DATA HAS BACKED OFF ON THAT A BIT.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
VERTICALLY STACKED CLOSED LOW WILL REMAIN LOCKED IN ACROSS MID
ATLC REGION TONIGHT. ONE AREA OF SHOWERS WILL LIFT N ACROSS
CENTRAL AND W MA THROUGH LATE AFTERNOON. MEANWHILE ADDITIONAL
SHOWERS DEVELOPING SOUTH OF LONG ISLAND AND HI-RES GUIDANCE SHOWS
THIS BLOSSOMING AS IT LIFTS N ACROSS CENTRAL/W NEW ENG THIS
EVENING AS VORT LOBE ROTATES AROUND UPPER LOW. WILL HAVE A PERIOD
OF LIKELY POPS THIS EVENING AND CANT RULE OUT AN ISOLD TSTM
WESTERN ZONES AS MID LEVEL TEMPS COOL WHICH WILL STEEPENING THE
LAPSE RATES WITH TT INCREASING INTO THE LOWER 50S.

OTHERWISE...EXPECT AREAS OF LOW CLOUDS AND FOG TO DEVELOP LATER
TONIGHT ALONG WITH PATCHY DRIZZLE GIVEN ABUNDANT LOW LEVEL
MOISTURE IN PLACE. TEMPS WILL REMAIN IN THE 40S.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY ...
VERTICALLY STACKED LOW WILL GRADUALLY WEAKEN AS IT DRIFTS EAST
OVER THE OCEAN AND BECOMES AN OPEN WAVE. SYNOPTIC FORCING IS
WEAK...BUT 500 MB TEMPS AROUND -21C WITH MID LEVEL LAPSE RATES
7-7.5 C/KM SUPPORTS SCT SHOWERS DEVELOPING WITH ISOLD TSTMS
POSSIBLE BUT MOST OF THE TIME IT WILL BE DRY. GIVEN LOW WBZ
HEIGHTS CANT RULE OUT SMALL HAIL. MID LEVELS DRY OUT AFT 18Z
WHICH WILL LIMIT CONVECTION THREAT LATER IN THE DAY.

THERE REMAINS CONSIDERABLE LOW LEVEL MOISTURE SATURDAY SO LOW
CLOUDS AND FOG WILL LINGER THROUGH MUCH OF THE MORNING AND WHILE
THERE MAY BE SOME BREAKS OF SUN IN THE AFTERNOON...CONFIDENCE IS
LOW. TEMPS REACHING LOWER 60S SOUTH OF THE PIKE WITH 50S TO THE
NORTH.

SATURDAY NIGHT...
NORTHERN STREAM SHORTWAVE APPROACHING FROM THE GT LAKES WILL
ACT AS A KICKER AND FINALLY PUSH MID LEVEL LOW EAST.
HOWEVER...THE ATTENDING COLD FRONT WILL BE MOVING INTO W NEW ENG
TOWARD 12Z. DEEP MOISTURE AXIS PRECEDING THE FRONT ALONG WITH
LEFT EXIT REGION OF THE UPPER LEVEL JET WILL LEAD TO A FRONTAL
BAND OF SHOWERS WHICH WILL MOVE INTO W NEW ENG TOWARD
DAYBREAK...BUT SHOULD BE DELAYED UNTIL SUNDAY MORNING FOR AREAS
FURTHER EAST.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...

* SHOWERS SUN AM BUT TURNING PARTLY SUNNY/WINDY DURING THE AFTERNOON
* DRY AND MILD MONDAY AFTERNOON BUT IT WILL BE BREEZY
* MODELS BACKING OFF ON COOL/WET WEATHER TUE/WED BUT NOT SET IN STONE
* SEASONABLE TO EVEN ABOVE NORMAL TEMPS LIKELY NEXT THU/FRI

DETAILS...

SUNDAY...

MOST GUIDANCE HAS HAS A COLD FRONT CROSSING THE REGION SUNDAY
MORNING.  ENOUGH FORCING/LOW LEVEL MOISTURE WITH THE FRONT THAT WILL
LIKELY SEE A BAND OF SCATTERED SHOWERS WORK ACROSS THE REGION.
MARGINAL ELEVATED INSTABILITY WILL BE IN PLACE AHEAD OF THE
FRONT...SO THERE IS A LOW RISK FOR A FEW EMBEDDED THUNDERSTORMS.
CONFIDENCE WAS NOT HIGH ENOUGH TO INSERT INTO THE FORECAST AT THIS
TIME...BUT SOMETHING WILL NEED TO WATCH.  IT APPEARS THAT THE FRONT
WILL BE OFF THE COAST SUNDAY AFTERNOON...RESULTING IN SKIES BECOMING
PARTLY SUNNY. THIS SHOULD ALLOW HIGH TEMPS TO REACH THE MID 60S IN
MOST LOCATIONS.  BUFKIT SOUNDINGS SHOW EXCELLENT MIXING WITH
WESTERLY WIND GUSTS OF 25 TO 40 MPH EXPECTED TO DEVELOP BY MID TO
LATE AFTERNOON.

MONDAY...

WESTERLY FLOW ALOFT AND AT THE SURFACE CONTINUES ON MONDAY AND MODEL
CROSS SECTIONS INDICATE AT LEAST PARTIAL SUNSHINE.  ALTHOUGH 850T
ARE ONLY BETWEEN +2C AND +4C...WESTERLY FLOW AND SOME SUN THIS TIME
OF YEAR SHOULD ALLOW AFTERNOON HIGH TEMPS TO REACH WELL INTO THE 60S
TO PERHAPS EVEN SOME LOWER 70S.  IT WILL BE BREEZY THOUGH WITH
WESTERLY WIND GUSTS OF 20 TO 30 MPH.

TUESDAY AND WEDNESDAY...

THERE HAS BEEN A CONSIDERABLE SHIFT WITH THE AFTERNOON MODEL
GUIDANCE.  LAST NIGHT/S 00Z MODELS DEPICTED A WAVE OF LOW PRESSURE
TRACKING JUST SOUTH OF OUR REGION...RESULTING IN RAW EASTERLY WINDS
AND A PERIOD OF COOL/WET WEATHER. MOST OF THE 12Z GUIDANCE HAS
BACKED AWAY FROM THAT...AS THEY NOW SHOW CANADIAN HIGH PRESSURE
FORCING THE LOW WELL TO OUR SOUTH.  THE RESULT WOULD BE PARTLY SUNNY
SKIES WITH JUST THE LOW RISK FOR A FEW BRIEF SHOWERS AND MILD
AFTERNOONS.

WE DID NOT WANT TO MAKE A DRASTIC ADJUSTMENT BASED ON JUST THE 12Z
GUIDANCE 4 TO 5 DAYS IN THE FUTURE...BUT DID TREND MILDER AND
LOWERED POPS.  A FEW 12Z GEFS MEMBERS ALONG WITH THE CMC STILL
INDICATE THE POTENTIAL FOR A PERIOD OF COOL/WET WEATHER.  SO TO
SUMMARIZE...ITS TOO EARLY TO LOCK IN A DRY/MILD SOLUTION BUT DID
TREND A BIT MORE IN THAT DIRECTION.

THURSDAY AND FRIDAY...

SEASONABLE TO EVEN ABOVE NORMAL TEMPERATURES EXPECTED.  DRY WEATHER
LIKELY THURSDAY...BUT A COLD FRONT MAY BRING A PERIOD OF SHOWERS
SOMETIME FRIDAY AND/OR FRIDAY NIGHT.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH SATURDAY NIGHT/...

THROUGH 00Z...MVFR CIGS. A FEW SHOWERS LIFTING N THROUGH CT/RI
AND CENTRAL/W MA.

TONIGHT...MODERATE CONFIDENCE.

CONDITIONS LOWERING TO IFR/LIFR IN STRATUS AND FOG. SHOWERS MOST
PREVALENT IN THE EVENING...CENTRAL/W NEW ENG AND CANT RULE OUT A
RUMBLE OF THUNDER.

SATURDAY...MODERATE CONFIDENCE.

IFR/LIFR IN THE MORNING GRADUALLY IMPROVING DURING THE
AFTERNOON...BUT TIMING IS VERY MUCH UNCERTAIN. SCT SHOWERS
DEVELOPING AND ISOLD TSTMS POSSIBLE.

SATURDAY NIGHT...MODERATE CONFIDENCE.

CONDITIONS LOWERING TO IFR/LIFR AGAIN IN STRATUS AND PATCHY FOG.
FRONTAL BAND OF SHOWERS MOVE INTO W NEW ENG 09-12Z.

KBOS TERMINAL...MODERATE CONFIDENCE. WILL LIKELY SEE IFR
CIGS/VSBYS DEVELOPING TONIGHT. TIMING UNCERTAIN.

KBDL TERMINAL...MODERATE CONFIDENCE. CIGS LOWERING TO IFR. TIMING
UNCERTAIN.

OUTLOOK /SUNDAY THROUGH WEDNESDAY/...

SUNDAY...MODERATE TO HIGH CONFIDENCE.  MVFR-IFR CONDITIONS WITH A
BAND OF SCATTERED SHOWERS SUNDAY MORNING SHOULD IMPROVE TO VFR
DURING THE AFTERNOON.  WESTERLY WINDS WILL INCREASE DURING THE
AFTERNOON WITH 25 TO 35 KNOT GUSTS EXPECTED.

SUNDAY NIGHT AND MONDAY...HIGH CONFIDENCE IN VFR CONDITIONS.

TUESDAY AND WEDNESDAY...LOW CONFIDENCE.  WILL DEPEND ON THE
TRACK/STRENGTH OF LOW PRESSURE APPROACHING FROM THE WEST.  LATEST
INDICATIONS DO FAVOR VFR CONDITIONS WITH LOW STAYING WELL TO OUR
SOUTH.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH SATURDAY NIGHT/...MODERATE CONFIDENCE.

TONIGHT...A PERIOD OF EASTERLY GUSTS 20-25 KT ACROSS S COASTAL
WATERS WILL DIMINISH THIS EVENING BUT E SWELL WILL KEEP SEAS
ABOVE 5 FT OVER THE OUTER WATERS TONIGHT. SCA CONTINUES. VSBYS
LOWERING IN AREAS OF FOG. EVENING SHOWERS.

SATURDAY...E/NE WINDS LESS THAN 15 KT WILL BECOME LOCALLY ONSHORE
IN THE AFTERNOON AS SEABREEZES DEVELOP. LINGERING SWELL OVER THE
SOUTH COASTAL WATERS. VSBYS REDUCED IN MORNING FOG. LOW RISK OF
SCATTERED SHOWERS WITH ISOLATED T-STORM POSSIBLE.

SATURDAY NIGHT...SOUTHERLY WINDS INCREASING LATE AHEAD OF
APPROACHING COLD FRONT...BUT BELOW SCA. VSBYS MAY BE REDUCED IN
FOG. SHOWERS SHOULD HOLD OFF UNTIL SUN MORNING.

OUTLOOK /SUNDAY THROUGH WEDNESDAY/...

SUNDAY AND MONDAY...MODERATE TO HIGH CONFIDENCE.  WESTERLY WIND
GUSTS OF 20 TO 30 KNOTS EXPECTED WITH GOOD MIXING BEHIND THE COLD
FRONT.  STRONGEST OF THOSE WINDS WILL BE NEAR SHORE...ESPECIALLY MID
TO LATE SUNDAY AFTERNOON WHERE THERE IS A LOW RISK A FEW PLACES
BRIEFLY APPROACH 35 KNOTS.

TUESDAY AND WEDNESDAY...LOW CONFIDENCE.  MODELS HAVE BACKED OFF ON
LOW PRESSURE TRACKING NEAR SOUTHERN NEW ENGLAND AS CANADIAN HIGH
PRESSURE TRIES TO SUPPRESS IT SOUTH.  THIS IS STILL NOT SET IN
STONE...BUT IF LATER MODEL RUNS HOLD WINDS/SEAS MAY BE BELOW SCA
HEADLINES OVER THIS TIME.

&&

.TIDES/COASTAL FLOODING...
VERY HIGH ASTRO TIDES TONIGHT /AROUND MIDNIGHT/ WITH BOSTON 12.3 FT
AT 1146 PM. MINIMAL SURGE THIS AFTERNOON BUT WITH MODEST ONSHORE
WINDS WILL LIKELY SEE A SURGE BELOW 0.5 FT AT HIGH TIDE. THAT/S
SUFFICIENT FOR A MODERATE TO HIGH RISK OF MINOR COASTAL FLOODING
ENTIRE EASTERN MA COASTLINE SO COASTAL FLOOD ADVISORY WILL
CONTINUE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO 2 AM EDT
     SATURDAY FOR MAZ007-015-016-019-022-024.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
     ANZ232>234.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT SATURDAY FOR ANZ235-237-
     254>256.
     SMALL CRAFT ADVISORY UNTIL 2 PM EDT SATURDAY FOR ANZ250.
     SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ251.

&&

$$
SYNOPSIS...KJC/FRANK
NEAR TERM...KJC
SHORT TERM...KJC
LONG TERM...FRANK
AVIATION...KJC/FRANK
MARINE...KJC/FRANK
TIDES/COASTAL FLOODING...



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