Area Forecast Discussion
Issued by NWS Boston, MA

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FXUS61 KBOX 050913
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
513 AM EDT TUE MAY 5 2015

.SYNOPSIS...
A WEAK COLD FRONT MAY BRING A FEW BRIEF SHOWERS TODAY...BUT DRY
WEATHER AND MILD TEMPERATURES WILL DOMINATE.  LITTLE CHANGE IS
EXPECTED THROUGH THE WEEKEND...WITH MILD TO WARM AFTERNOON/S AND
MAINLY DRY WEATHER PERSIST. A SLOW MOVING FRONT MAY BRING A FEW
SHOWERS LATE THIS WEEKEND INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A WEAK COLD FRONT WILL SLOWLY WORK ACROSS THE REGION TODAY.
INSTABILITY AND LOW LEVEL MOISTURE IS FAIRLY LIMITED...SO THE VAST
MAJORITY OF THE DAY WILL BE DRY.  HOWEVER...A FEW SHOWERS WILL
LIKELY DEVELOP WITH THE FRONT BUT AREAL COVERAGE SHOULD BE LIMITED
AND ACTIVITY SHOULD NOT LAST LONG AT A GIVEN LOCATION.  RAINFALL
AMOUNTS SHOULD GENERALLY BE JUST A TRACE TO JUST A FEW HUNDREDTHS OF
AN INCH IN MOST LOCALES.  DID NOT INCLUDE THE MENTION OF THUNDER AS
INSTABILITY LOOKS TOO MARGINAL.

PLENTY OF MID LEVEL CLOUDINESS WILL BE AROUND DURING THE
MORNING...BUT STILL EXPECT PEEKS OF SUN.  AS THE AFTERNOON WEARS ON
EXPECT SUNSHINE TO BECOME MORE PREVALENT AS DRIER AIR WORKS IN
BEHIND THE COLD FRONT.

GIVEN VERY MILD START...HIGH TEMPS IN MOST LOCALES SHOULD CLIMB WELL
UP INTO THE 70S.  ITS NOT OUT OF THE QUESTION THAT A SPOT LOCATION
OR TWO HITS 80.  HOWEVER...ACROSS THE IMMEDIATE COAST WEAKENING
PRESSURE GRADIENT BEHIND THE COLD FRONT WILL ALLOW COOLING SEA
BREEZES TO DEVELOP.  IN THESE LOCATIONS...MILD LATE MORNING TEMPS
WILL PROBABLY FALL BACK INTO THE UPPER 50S AND LOWER 60S...INCLUDING
BOSTON.  JUST INLAND FROM THE COAST THOUGH IT WILL REMAIN QUITE MILD
EVEN BEHIND THE FRONT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT AND WEDNESDAY...

DRY AND PLEASANT WEATHER EXPECTED FOR MOST OF TONIGHT AS HIGH
PRESSURE BUILDS IN BEHIND THE COLD FRONT.  LOW TEMPS WILL MAINLY BE
IN THE 40S...TO LOWER 50S.

A MOISTURE STARVED SHORTWAVE WILL DROP DOWN IN WEST TO NORTHWEST
FLOW ALOFT WED MORNING.  NOT SURE IF IT WILL TRACK FAR ENOUGH
NORTHWEST TO RESULT IN A BRIEF PERIOD OF SCATTERED SHOWERS ACROSS
ANY PORTION OF OUR REGION.  BEST SHOT IS NORTHERN CT...AND PERHAPS
EVEN INTO PART OF RHODE ISLAND AND SOUTHEAST MA FOR A SHORT TIME.
REGARDLESS...EVEN IF A FEW SHOWERS OCCUR THEY WILL BE SHORT-LIVED
AND NOT AMOUNT TO MUCH.  MORE IN THE WAY OF SUNSHINE SHOULD DEVELOP
FROM NORTH TO SOUTH THROUGH WED AFTERNOON.  HIGHS SHOULD GENERALLY
REACH WELL INTO THE 70S IN MOST LOCATIONS...WITH THE WARMEST
READINGS NORTH OF THE PIKE WHERE THE MOST SUNSHINE IS EXPECTED.  ITS
ALSO POSSIBLE THAT AREAS NEAR THE SOUTH COAST DO NOT REACH 70 ON
WEDNESDAY...IF CLOUDS HANG ON LONGER THEN EXPECTED.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...

HIGHLIGHTS...

* SPRING TO SUMMER-LIKE TEMPERATURES THROUGH EARLY NEXT WEEK
* HIGH PRESSURE WILL KEEP MAINLY DRY CONDITIONS INTO THIS WEEKEND
* A SLOW MOVING FRONT MAY BRING SCATTERED SHOWERS SUN INTO MON

OVERVIEW AND MODEL PREFERENCES...

00Z GEFS/12Z ECENS REMAIN IN GOOD AGREEMENT WITH OVERALL UPPER
LEVEL STEERING FLOW IN KEEPING AMPLIFIED PATTERN ACROSS THE LOWER
48 THROUGH MOST OF THIS FORECAST PERIOD. NOTING LONG WAVE
TROUGHING WITH A FEW CUTOFF SHORT WAVES DIVE S INTO THE BASE OF
THE TROUGH INTO THIS WEEKEND WHILE LONG WAVE RIDGE SLOWLY BUILDS E
AS IT NOSES N THROUGH EASTERN QUEBEC TO LABRADOR. ALSO NOTING
NEARLY STATIONARY CUTOFF LOW OFF THE SE U.S. COAST WITH SURFACE
LOW/POSSIBLE SUBTROPICAL SYSTEM LATE IN THE WEEK OR THIS WEEKEND.
WHILE THIS SYSTEM WILL NOT DIRECTLY AFFECT THE REGION... IT COULD
CAUSE THE RIDGE TO HOLD IN PLACE AND SLOW AN APPROACHING COLD
FRONT FOR LATE THIS WEEKEND INTO NEXT MONDAY.

00Z MODEL SUITE ALSO IN FAIRLY GOOD AGREEMENT INTO THIS WEEKEND...
THEN THE GFS LOOKS TO BREAK DOWN RIDGING FASTER THAN GGEM/ECMWF...
MAINLY DUE TO SHORT WAVE TRYING TO WORK OUT OF CENTRAL CANADA
WHICH FLATTENS OUT THE RIDGE. WITH OVERALL BLOCKING PATTERN IN
PLACE ACROSS NORTH AMERICA AND FURTHER E ACROSS THE ATLC...FEEL
THIS WILL BE SLOW TO BREAK DOWN SO THINK THE SLOWER GUIDANCE IS
THE WAY TO GO FOR SUN-MON. HOWEVER...WITH THE WIDE MODEL
SOLUTIONS...HAVE LOW CONFIDENCE FROM SATURDAY INTO EARLY NEXT
WEEK.

LEANED TOWARD A BLEND OF MODEL GUIDANCE INTO THIS WEEKEND...THEN
BLENDED TOWARD THE ENSEMBLES FOR SUN-MON WHICH WAS CLOSE TO THE
HPC GUIDANCE. THIS YIELDED GOOD CONTINUITY TO THE PREVIOUS
FORECAST.

DETAILS...

WEDNESDAY NIGHT...EXPECT STALLED FRONT NEAR THE S COAST TO TEND TO
WASH OUT AS IT SHIFTS A BIT FURTHER S AS HIGH PRES AT THE SURFACE
AND ALOFT SLOWLY PUSHES ACROSS THE REGION. WILL SEE GENERALLY DRY
CONDITIONS WITH LIGHT/VRBL WINDS.

THURSDAY-FRIDAY...RIDGING BUILDS E ACROSS NEW ENGLAND INTO EASTERN
CANADA DURING THIS TIMEFRAME. EXPECT LIGHT/VRBL WINDS EARLY THU TO
BECOME S-SW. THIS WILL KEEP MILD TEMPS IN PLACE EXCEPT ALONG THE S
COAST WHERE THEY WILL BE TEMPERED WITH THE GENERAL ONSHORE WIND
FLOW. MAY ALSO SEE BRIEF SEA BREEZES ALONG THE E COAST MAINLY ON
FRIDAY. ALSO...DUE TO SEA SURFACE TEMPS RUNNING IN THE MID-UPPER
40S AND MILD TEMPS DURING THE NIGHTTIME HOURS...MAY SEE OVERNIGHT
PATCHY FOG DEVELOP MAINLY ALONG THE COAST WHILE INCREASING DEWPTS
MAY ALSO MEAN BRIEF PATCHY FOG ACROSS THE NORMALLY SUSCEPTIBLE
INLAND LOCATIONS EACH NIGHT.

HIGHS BOTH DAYS AWAY FROM THE S COAST WILL BE IN THE 70S...
POSSIBLY UP TO AROUND 80 ACROSS PORTIONS OF THE CT VALLEY BOTH
DAYS.

SATURDAY THROUGH MONDAY...AS MENTIONED ABOVE...MODEL SOLUTIONS
WIDEN. HAVE MENTIONED ONLY SLIGHT CHANCE POPS MAINLY N OF THE MASS
PIKE SAT AFTERNOON/NIGHT. INCREASED POPS TO ONLY LOW CHANCE FOR
SUN/MON FOR MOST AREAS...BUT WILL DEPEND UPON TIMING OF THE
APPROACHING FRONT. EXPECT MILD TEMPS TO REMAIN IN PLACE THROUGH
THIS WEEKEND WITH HIGHS IN THE 70S /EXCEPT COOLER ALONG IMMEDIATE
S COAST/.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TODAY THROUGH WEDNESDAY/...

TODAY...HIGH CONFIDENCE.  LLWS AROUND 2 THOUSAND FEET OF 40 TO 50
KNOTS WILL WEAKEN AFTER 12Z. OTHERWISE...VFR CONDITIONS EXPECTED THE
VAST MAJORITY OF THE DAY.  VERY BRIEF LOCALIZED MVFR CONDITIONS ARE
POSSIBLE IN A FEW BRIEF SHOWERS LATER THIS MORNING AND AFTERNOON
WITH A COLD FRONT.

TONIGHT AND WEDNESDAY...HIGH CONFIDENCE.  MAINLY VFR CONDITIONS.  A
BRIEF PERIOD OF ISOLATED TO SCATTERED SHOWERS MAY AFFECT NORTHERN CT
AND POSSIBLY A PART OF RI/SOUTHEAST MA FOR A TIME WED AM.  THIS MAY
RESULT IN VERY BRIEF LOCALIZED MVFR CONDITIONS IF ANY OCCUR.

KBOS TAF...HIGH CONFIDENCE IN TAF.  SEA BREEZES EXPECTED TO DEVELOP
THIS AFTERNOON AS A RESULT OF A WEAKENING PRESSURE GRADIENT BEHIND A
COLD FRONT.

KBDL TAF...HIGH CONFIDENCE IN TAF.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

HIGH CONFIDENCE THROUGH THE PERIOD. VFR AND DRY CONDITIONS. LOW
RISK FOR PATCHY FOG EACH NIGHT FROM AROUND MIDNIGHT THROUGH SUNRISE
WITH LOCAL MVFR-IFR CIGS/VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TODAY THROUGH WEDNESDAY/...

TODAY THROUGH WEDNESDAY...HIGH CONFIDENCE.  MARGINAL SMALL CRAFT
SEAS WILL CONTINUE INTO MID TO LATE THIS MORNING ACROSS THE OUTER-
WATERS BEFORE DROPPING BELOW CRITERIA.  OTHERWISE...WINDS/SEAS WILL
REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS THROUGH WEDNESDAY UNDER
A WEAK RIDGE OF HIGH PRESSURE.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...HIGH CONFIDENCE
THROUGH THE PERIOD.

WEDNESDAY NIGHT...LIGHT/VRBL WINDS BECOME S-SW AROUND OR AFTER
MIDNIGHT AT 15 KT OR LESS. SEAS 3 FT OR LESS.

THURSDAY...W-SW WINDS UP TO 15 KT ACROSS THE OPEN WATERS DURING
THE AFTERNOON. SEAS REMAIN BELOW 5 FT.

THURSDAY NIGHT THROUGH SATURDAY...SW WINDS 15 KT OR LESS WITH SEAS
2-4 FT. LOW CHANCE OF 5 FT SEAS ON THE EASTERN OUTER WATERS SAT
AFTERNOON/NIGHT.

&&

.FIRE WEATHER...
MAINLY DRY WEATHER WITH LITTLE APPRECIABLE RAINFALL WILL CONTINUE
THROUGH AT LEAST SATURDAY IF NOT INTO SUN/MON.  WHILE WINDS FOR THE
REST OF THE WORK WEEK WILL PROBABLY NOT BE STRONG ENOUGH FOR FIRE
WEATHER HEADLINES...WE MAY HAVE TO BE MORE CONCERNED BY SATURDAY.
THERE WILL BE AT LEAST A BIT MORE POTENTIAL FOR SOME MARGINAL FIRE
WEATHER HEADLINE WIND GUSTS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR ANZ250-
     254>256.

&&

$$
SYNOPSIS...FRANK/EVT
NEAR TERM...FRANK/EVT
SHORT TERM...FRANK
LONG TERM...EVT
AVIATION...FRANK/EVT
MARINE...FRANK/EVT
FIRE WEATHER...FRANK



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