Area Forecast Discussion
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000
FXUS61 KBOX 290201
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1001 PM EDT THU APR 28 2016

.SYNOPSIS...
HIGH PRESSURE STRETCHING FROM CENTRAL CANADA TO NORTHERN NEW
ENGLAND WILL YIELD MILD AFTERNOONS AND CHILLY NIGHTS. A RETURN TO
UNSETTLED AND COOL WEATHER IS EXPECTED SUNDAY INTO MONDAY AS LOW
PRESSURE TRACKS SOUTH OF NEW ENGLAND. A DRYING TREND FOLLOWS
TUESDAY...HOWEVER MORE UNSETTLED WEATHER IS POSSIBLE MID TO LATE
NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
10 PM UPDATE...THE FORECAST IS GENERALLY ON TRACK THIS EVENING.
MADE A FEW ADJUSTMENTS TO THE TEMPERATURES AND DEWPOINTS TO
ACCOUNT FOR THE LATEST TRENDS. THERE IS AN AREA OF LIGHT
SHOWERS/SPRINKLES ACROSS SOUTHERN CONNECTICUT AND SOUTHERN RHODE
ISLAND. EXPECT THESE TO REMAIN VERY LIGHT AS DEWPOINT DEPRESSIONS
ACROSS MUCH OF THE REGION ARE STILL 15-20 DEGREES. PREVIOUS
DISCUSSION FOLLOWS.

===========================================================================

TONIGHT...

WHERE CAN WE EXPECT TO SEE CLOUDS AND WET WEATHER? CONFIDENCE IS
TOWARDS THE S/W WHERE THE MID-UPPER LEVEL CONFLUENCE RELAXES IN A
REGIME OF WEAK ISENTROPIC ASCENT AND SOME MID-LEVEL FORCING PARENT
WITH STRETCHED VORTEX ENERGY. ANY OUTCOMES WOULD BE LIGHT MAINLY
OVER S/W CT N OF A W TO E FRONTAL BOUNDARY OFF THE DELMARVA / NJ
COASTLINE. NOT A ROBUST EVENT. HARDLY A WASHOUT. THINKING NUISANCE.
SPRINKLES TO VERY LIGHT SHOWERS. FOCUS MAINLY SW CT. DRY ELSEWHERE
PER ACCOMPANYING AIRMASS AND SUBSIDENCE ASSOCIATED WITH HIGH TO N.
NON-NAM CONSENSUS.

SO OVERALL A MOSTLY DRY AND QUIET NIGHT FOR MUCH OF S NEW ENGLAND.
INCREASING AND THICKENING CLOUDS FROM THE S/W. SUBSEQUENTLY MILDER
WITH LOWS AROUND THE UPPER 30S S BUT COOLER N UNDER THE INFLUENCE OF
HIGH PRESSURE AND LIGHT WINDS UNDER LESS CLOUDS. CAN NOT RULE OUT
RADIATIONAL COOLING ACROSS THE HIGH TERRAIN AND WITHIN INTERIOR
VALLEYS OF N MASSACHUSETTS WHICH COULD DRIVE LOWS DOWN TO THE UPPER
20S IF CONDITIONS ARE RIGHT.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY...

KEEPING IT DRY WITH CLOUDS LINGERING. POTENT MID LEVEL VORTEX OUT OF
THE S GREAT LAKES INVOKES WEAK LOW PRESSURE ACROSS THE APPALACHIANS
TOWARDS THE DELMARVA LATE. ISALLOBARIC RESPONSE MAINTAINS DRY AIR
AND HIGH PRESSURE ACROSS MUCH OF NEW ENGLAND WITH A COMPONENT OF
DOWN-SLOPING AIR AND SUBSIDENCE THROUGH THE LOW LEVELS. CONSIDERING
THE E ONSHORE FLOW AND THE LIKELIHOOD OF CLOUDS LINGERING MAY NUDGE
A FEW DEGREES LOWER ON HIGHS FORECAST AROUND THE UPPER 50S.

FRIDAY NIGHT...

RENEWED FOCUS OF LIGHT SHOWERY WEATHER S/W. VORTEX AND ACCOMPANYING
SURFACE LOW EMERGING OFF THE DELMARVA WITH PARENT JET ENERGY AND
DYNAMICS. CRUX OF FORCING / ISENTROPIC ASCENT SLIDES S OF THE REGION
AS HIGH PRESSURE AND DRY AIR REMAIN INFLUENTIAL N/E WITH SINKING AIR
IN THE LOW LEVELS. AM CONFIDENT THAT SW CT COULD SEE LIGHT SHOWERS.
MAJORITY OF WET WEATHER WILL STAY S AND OFFSHORE. MAJORITY OF THE
ACTIVITY DURING THE EVENING WITH CLOUDS IN GREATER ABUNDANCE S/W.

SO OVERALL A DRY FORECAST FOR MUCH OF S NEW ENGLAND. A CLEARING
TREND WITH HIGH PRESSURE BUILDING BACK IN AND SINKING AIR BY
MIDNIGHT AND CONTINUING THROUGH SATURDAY MORNING. WINDS TURNING
LIGHT WITH CLEARING...COULD SEE SOME PLACES RADIATE OUT DECENTLY AS
LOWS DROP INTO THE 30S. FOCUS MAINLY N/E ESPECIALLY WITH SANDY
SOILS.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...

* DRY AND MILD SATURDAY W/HIGHS 60-65...50S ALONG THE COAST
* COOLER WITH PERIODS OF RAIN SUN AND MON
* DRYING TREND LIKELY TUE ALONG WITH MILDER TEMPS
* MORE UNSETTLED WEATHER POSSIBLE MID TO LATE NEXT WEEK

SATURDAY ... WEAK MID LEVEL ANTICYCLONIC FLOW OVER THE AREA PROVIDES
SURFACE RIDGING AND DRY WEATHER ACROSS THE REGION. THUS EXPECT LOTS
OF SUNSHINE. 850 TEMPS HOVERING AROUND 0C BUT MODEL SOUNDINGS
INDICATE A DEEP BLYR WITH MIXING UP TO 800 MB OR SO. THEREFORE HIGHS
60-65 SEEM ACHIEVABLE INLAND WITH SEABREEZES ALONG THE COAST KEEPING
TEMPS IN THE 50S NEAR SHORE. OVERALL A REAL NICE DAY BY LATE APRIL
STANDARDS.

SUN INTO MON ... MODELS CONTINUE TO SPEED UP THE ARRIVAL OF MOISTURE
INTO NEW ENGLAND ASSOCIATED WITH UPPER LOW CURRENTLY OVER THE 4
CORNERS REGION AND DESERT SOUTHWEST. THIS FASTER TREND SEEMS
REASONABLE GIVEN THE UPPER AIR PATTERN FEATURES CONFLUENT FLOW
ACROSS NEW ENGLAND. SUNDAY MAY BEGIN DRY ESPECIALLY ACROSS RI AND
EASTERN MA WHERE ALL GUID INCLUDING THE NEW 12Z ECMWF AND 12Z UKMET
HAVE PRECIP JUST CROSSING THE NY/WESTERN NEW ENGLAND BORDER AT 12Z
SUNDAY. HOWEVER WITH THE FAST CONFLUENT FLOW ALOFT RAIN WILL LIKELY
OVERSPREAD THE AREA QUICKLY FROM WEST TO EAST SUNDAY. ALTHOUGH STILL
TOO FAR OUT IN TIME TO NAIL DOWN SPECIFIC TIMING. AS PREVIOUS
FORECASTER MENTIONED WITH SURFACE WAVE TRACKING SOUTH OF NEW ENGLAND
THE COMBINATION OF NE WINDS OFF THE CHILLY OCEAN COMBINED WITH
PERIODS OF RAIN WILL LIMIT HIGHS TO THE U40S AND L50S...POSSIBLY
COOLER. THEREFORE HIGHS SUNDAY AND MONDAY WERE DERIVED FROM THE
COOLER 2 METER MODEL TEMPS VS. THE MILDER MOS TEMPS. COOLEST
READINGS LIKELY ACROSS CT AND WESTERN-CENTRAL MA GIVEN DRY WEATHER
MAY LINGER FOR A TIME ACROSS RI AND EASTERN MA EARLY SUNDAY.

TUE ... SHOULD BE A PERIOD OF DRY WEATHER AFTER SUN/MON RAIN EVENT
WITH MEAN TROUGH AXIS MOVING OFFSHORE. GIVEN ENSEMBLE MEAN 850 TEMPS
OVER THE AREA ARE AROUND +2C/+3C AND SURFACE PRESSURES NEAR 1015
MB...FULL SUNSHINE COULD POTENTIALLY YIELD HIGHS BACK INTO THE 60S
INLAND TUE. OF COURSE COOLER NEAR THE COAST GIVEN WEAK PGRAD
SUPPORTING POTENTIAL SEABREEZES.

WED INTO THU ... LOOKS UNSETTLED AS ENSEMBLES AND DETERMINISTIC
GUIDANCE SUGGEST MEAN TROUGH RELOADS WITH NEW JET ENERGY OVER
SOUTHEAST CANADA AND THE NORTHEAST. THIS SEEMS REASONABLE GIVEN THE
LARGE SCALE FLOW FEATURES A POSITIVE HEIGHT ANOMALY OVER THE ROCKIES
AND A CORRESPONDING DOWNSTREAM NEGATIVE HEIGHT ANOMALY OVER HUDSON
BAY. THIS WILL SUPPORT EAST COAST TROUGHING AND POTENTIAL UNSETTLED
WEATHER HERE IN THE FORM OF SHOWERS/PERIODS OF RAIN. COOLER TOO
GIVEN CLOUDS/PRECIP AND NORTHEAST FLOW.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...

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

7 PM UPDATE ... NOT MUCH CHANGE TO 18Z AND 21Z TAFS. DRY WEATHER
PREVAILS WITH THE EXCEPTION OF SOME VERY LIGHT RAIN/SPRINKLES
TONIGHT ACROSS CT/RI AND SOUTHEAST MA. EARLIER DISCUSSION BELOW.

===================================================================

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

VFR THROUGH FRIDAY NIGHT. LOW RISK MVFR ACROSS S/W CT TONIGHT AND
AGAIN FRIDAY NIGHT. E/SE FLOW TONIGHT BECOMING MORE E AND BREEZY
INTO FRIDAY EVENING BEFORE BECOMING LIGHT AND BACKING N INTO
SATURDAY MORNING.

KBOS TERMINAL...VFR. SEA-BREEZE ASHORE. FLOW TO REMAIN E THROUGH
FRIDAY EVENING. STRONGEST DURING THE AFTERNOON TO EVENING HOURS ON
FRIDAY.

KBDL TERMINAL...VFR.

OUTLOOK /SATURDAY THROUGH TUESDAY/...

SAT ... HIGH CONFIDENCE. MAINLY VFR CIGS.

SUNDAY INTO MONDAY...MODERATE TO HIGH CONFIDENCE ON TRENDS WITH MVFR
AND LOCALIZED IFR POSSIBLE IN PERIODS OF RAIN.

TUESDAY ... DRYING TREND WITH VFR POSSIBLE AND LIGHT WINDS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

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

MAINLY QUIET BOATING WEATHER AS HIGH PRESSURE REMAINS DOMINANT.
THERE IS A LOW RISK OF RAIN SHOWERS ON THE S WATERS CLOSER TO
BLOCK / LONG ISLAND TONIGHT AND AGAIN FRIDAY NIGHT.

E/SE FLOW BECOMING BREEZY INTO FRIDAY AFTERNOON AND EVENING WITH
POSSIBLE GUSTS UP TO 20 KTS DURING WHICH TIME ISOLATED 5 FOOT
SEAS ARE POSSIBLE OVER THE WATERS S OF ISLANDS. WINDS BACK NE INTO
SATURDAY MORNING.

OUTLOOK /SATURDAY THROUGH TUESDAY/...

SATURDAY ... QUIET BOATING WEATHER WITH LIGHT WINDS AND TRANQUIL
SEAS.

SUNDAY INTO MON ... INCREASING EASTERLY WINDS LATE SUN INTO MON AS
LOW PRES TRACKS TO THE SOUTH. A PERIOD OF SCA GUSTS POSSIBLE SUN
NIGHT INTO MON DEPENDING ON TRACK AND INTENSITY OF LOW PRES. ROUGH
SEAS GIVEN THE LONG ENE FETCH. VSBYS REDUCED AT TIMES IN SHOWERS AND
PATCHY FOG.

TUESDAY ... IMPROVING/DRYING TREND. LEFTOVER ENE SWELLS LIKELY FOR
THE OCEAN WATERS.

&&

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

&&

$$
SYNOPSIS...NOCERA/SIPPRELL
NEAR TERM...NOCERA/RLG/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...NOCERA
AVIATION...NOCERA/SIPPRELL
MARINE...NOCERA/SIPPRELL


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