Area Forecast Discussion
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000
FXUS61 KBOX 070909
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
509 AM EDT THU MAY 7 2015

.SYNOPSIS...
DRY WEATHER WITH UNSEASONABLY WARM AFTERNOONS WILL CONTINUE
THROUGH THIS WEEKEND...BUT A BACKDOOR COLD FRONT WILL BRING A
BRIEF PERIOD OF COOL TEMPERATURES ON FRIDAY ALONG THE EASTERN
MASSACHUSETTS COAST. THERE MAY BE SOME SCATTERED SHOWERS EARLY
NEXT WEEK WITH A SLOW MOVING FRONT FROM THE NORTH...THEN A COLD
FRONT LOOKS TO SWEEP EAST BY MID WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
***A SUNNY WARM AFTERNOON BUT WITH COMFORTABLE HUMIDITY LEVELS***

DESPITE A COOL START IN THE OUTLYING LOCATIONS VERY EARLY THIS
MORNING...TEMPS WILL QUICKLY RECOVER LATE THIS MORNING AND
AFTERNOON.

850 TEMPS BETWEEN +10 AND +11C COMBINED WITH SUNNY SKIES AND A DRY
AIRMASS IN PLACE WILL ALLOW FOR A WARM AFTERNOON.  HIGH TEMPS WILL
REACH INTO THE LOWER TO MIDDLE 80S AWAY FROM THE COAST.  SEA BREEZES
ON THE COAST WILL RESULT IN TEMPS SEVERAL DEGREES COOLER FOR AT
LEAST A PORTION OF THE DAY...BUT THESE MIGHT BE OVERCOME BY LATE
AFTERNOON ALONG THE EASTERN MA COAST ALLOWING EVEN BOSTON TO WARM TO
NEAR 80.

ALL IN ALL...A BEAUTIFUL SUNNY DAY WITH SUMMERLIKE AFTERNOON
TEMPERATURES BUT WITHOUT THE HUMIDITY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
***BACKDOOR COLD FRONT RESULTS IN FRIDAY AFTERNOON TEMPS IN THE 50S
  ALONG THE EASTERN MA COAST BUT WITH MIDDLE 80S IN WESTERN
  MA/NORTHERN CT***

TONIGHT...

QUIET WEATHER CONTINUES TONIGHT WITH A WEAK RIDGE OF HIGH PRESSURE
IN CONTROL.  LOW TEMPS MAINLY IN THE UPPER 40S TO THE LOWER 50S.
THE URBAN HEAT ISLAND OF BOSTON WILL BE THE MILD SPOT WITH LOW TEMPS
IN THE UPPER 50S.

FRIDAY...

HIGH PRESSURE ACROSS THE CANADIAN MARITIMES WILL SEND A BACKDOOR
COLD FRONT SOUTH INTO NORTHEAST MA DURING THE MORNING AND ACROSS THE
REST OF THE EASTERN MA COAST BY AFTERNOON.  THE FRONT SHOULD LOSE
ITS PUNCH AS IT TRIES TO ENTER CENTRAL MA.  THE RESULT WILL BE A
WIDE RANGE IN TEMPS...ESPECIALLY DURING THE AFTERNOON ACROSS OUR
REGION WHICH MAY EXCEED 30 DEGREES!

LATER SHIFTS WILL CERTAINLY NEED TO MAKE UPDATES TO THE TEMPERATURE
FORECAST...AS A SUBTLE SHIFT IN TIMING/LOCATION OF THE BACKDOOR
FRONT WILL MAKE A HUGE DIFFERENCE IN TEMPS. FOR NOW THINKING MUCH
OF THE REGION WILL QUICKLY WARM INTO THE LOWER TO MIDDLE 80S. THE
EXCEPTION WILL BE ON THE IMMEDIATE EASTERN MA COAST AND ESPECIALLY
NORTHEAST MA. THERE ARE DECENT PRESSURE RISES BEHIND THIS
FRONT...SO A BRIEF PERIOD OF NORTHEAST WIND GUSTS BETWEEN 20 AND
30 MPH ARE POSSIBLE ACROSS NORTHEAST MA INCLUDING BOSTON.

BY MID TO LATE AFTERNOON TEMPS WILL LIKELY RANGE FROM THE MIDDLE
50S ALONG THE EASTERN MA COAST INCLUDING BOSTON...TO THE MIDDLE
80S ACROSS THE WESTERN HALF OF MA/NORTHERN CT! DRY WEATHER
EXPECTED...ALTHOUGH THERE IS A LOW RISK OF AN ISOLATED
SHOWER/THUNDERSTORM LATE IN THE AFTERNOON/EARLY EVENING ALONG THE
EAST SLOPES OF THE BERKSHIRES WITH SOME MARGINAL INSTABILITY.

&&

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

 * SURFACE AND UPPER LEVEL RIDGING REMAINS IN PLACE ACROSS REGION
   WITH SW WINDS AND ABOVE NORMAL TEMPS THROUGH THIS WEEKEND
 * LOW CLOUDS AND FOG DEVELOP ALONG S AND SE COASTAL AREAS EACH
   OVERNIGHT INTO MID MORNING PERIOD
 * LOW PRESSURE OFF CAROLINA COAST MAY BRING SOME MOISTURE UP THE
   COAST AHEAD OF APPROACHING FRONT EARLY NEXT WEEK

DISCUSSION...

MODELS AND ENSEMBLES CONTINUE TO SIGNAL BLOCKING UPPER LEVEL
PATTERN IN PLACE ACROSS THE LOWER 48 AND BEYOND THROUGH THIS
WEEKEND...THEN NOTING CHANGES EARLY NEXT WEEK. CUTOFF LOW
PRES/LONG WAVE TROUGHING LOOKS TO BEGIN TO MIGRATE E LATE THIS
WEEKEND INTO EARLY NEXT WEEK OUT OF THE PLAINS STATES...WITH
SURFACE LOW PRES AND COLD FRONT WORKING E WHICH TRIES TO FLATTEN
OUT THE RIDGING ACROSS NEW ENGLAND INTO EASTERN CANADA. THERE IS
MORE CONSISTENCY AMONGST THE MODEL SUITE AS WELL AS PRETTY GOOD
CONTINUITY WITH THE ENSEMBLES THIS MORNING WHICH LENDS TO A BIT
MORE CONFIDENCE OF AN APPROACHING COLD FRONT AROUND THE TUESDAY
TIMEFRAME.

ANOTHER FEATURE TO MONITOR IS AREA OFF LOW PRES OFF THE CAROLINA
COAST BEING MONITORED BY THE TROPICAL PREDICTION CENTER. LOOKS
LIKE THIS SYSTEM WILL LIKELY EVOLVE INTO A SUBTROPICAL OR EVEN
TROPICAL SYSTEM...BUT WILL MOVE LITTLE AS IT IS TRAPPED BENEATH
THE UPPER LEVEL RIDGING WITH LIGHT STEERING CURRENTS THROUGH THIS
WEEKEND. HOWEVER...IT DOES LOOK LIKE IT MAY START TO SHIFT N-NE AS
THE TROUGHING OUT OF THE CENTRAL U.S. MAY GIVE THE SYSTEM A
PUSH...THOUGH IT WILL WEAKEN. MOISTURE FROM THE SYSTEM MAY FEED
TOWARD THE REGION...WHICH COULD ENHANCE ANY LIGHT PRECIP ASSOCIATED
WITH THE APPROACHING COLD FRONT...ALONG WITH INCREASING PWAT/S.

OVERALL...EXPECT DRY CONDITIONS FOR MOST AREAS THROUGH THIS
WEEKEND AS THE UPPER RIDGE KEEPS GOOD SUBSIDENCE IN PLACE.
INCREASING DEWPTS WILL BRING SUMMER LIKE MUGGINESS ON THE
PERSISTENT S-SW WINDS IN PLACE. EXPECT MILD TO WARM TEMPS TO
CONTINUE THIS WEEKEND INTO MONDAY. HIGHS WILL REACH THE MID 80S
ACROSS INLAND AREAS BOTH SUNDAY AND MONDAY...WITH A FEW SPOTS
POSSIBLY MAKING A RUN AT 90. MAY SEE SOME SCT SHOWERS TRY TO WORK
INTO CENTRAL AND WESTERN AREAS MONDAY WELL AHEAD OF STALLED FRONT
ACROSS NORTHERN NEW ENGLAND...BUT CONFIDENCE IS LOW FOR THIS.

EXPECT PERIODS OF LOW CLOUDS/FOG TO DEVELOP EACH OVERNIGHT INTO
MID MORNING TIMEFRAME THROUGH THIS WEEKEND ALONG THE S
COAST...CAPE COD AND THE ISLANDS WITH THE MILD...MOIST AIR OVER
THE COOLER OCEAN WATERS /SEA SURFACE TEMPS STILL IN THE MID-UPPER
40S THERE/. ALSO MENTIONED SOME SPRINKLES DURING FRI AND SAT
NIGHTS WITH PRETTY GOOD LL MOISTURE WORKING IN. MAY SEE SOME
PATCHY DRIZZLE AS WELL.

FOR NOW...HAVE FAIRLY LOW CONFIDENCE WITH THE APPROACH OF THE
COLD FRONT OUT OF THE GREAT LAKES AND OHIO VALLEY AROUND THE
TUESDAY TIMEFRAME...WHICH MAY BRING A BETTER CHANCE FOR SHOWERS.
AS PREVIOUSLY MENTIONED...COULD SEE SOME ENHANCED PRECIP IF
MOISTURE FROM LOW PRES DOWN THE COAST ADVECTS IN...BUT THIS IS
UNCERTAIN. DEPENDING UPON TIMING OF THE FRONT...MAY SEE CLEARING
CONDITIONS FOR WEDNESDAY.

&&

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TODAY THROUGH FRIDAY/...

TODAY AND TONIGHT...HIGH CONFIDENCE IN VFR CONDITIONS.  A PERIOD OF
EAST TO SOUTHEAST SEA BREEZES WILL PROBABLY DEVELOP FOR A FEW HOURS
LATE THIS MORNING INTO MID AFTERNOON ALONG PORTIONS OF THE IMMEDIATE
COAST.

FRIDAY...HIGH CONFIDENCE IN VFR CONDITIONS.  STRONG BACKDOOR COLD
FRONT MAY RESULT IN A BRIEF PERIOD OF NORTHEAST WIND GUSTS OF 20 TO
25 KNOTS ALONG THE NORTHEAST MA COAST FROM MID MORNING INTO THE
AFTERNOON.

KBOS TAF...HIGH CONFIDENCE IN VFR CONDITIONS.  MODERATE CONFIDENCE
ON TIMING AND IF AN EAST TO SOUTHEAST SEA BREEZE DEVELOPS FOR A FEW
HOURS THIS AFTERNOON.

KBDL TAF...HIGH CONFIDENCE IN TAF.

OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...

VFR. SW FLOW...MAY SEE GUSTS UP TO AROUND 20 KT DURING SUNDAY.
AREAS OF IFR CIGS/VSBYS IN LOW CLOUDS AND FOG ALONG THE S/SE-
SHORELINE TERMINALS DURING OVERNIGHT INTO MID MORNING PERIODS EACH
DAY. INCREASING CHANCES FOR SCT -SHRA DURING MONDAY.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TODAY THROUGH FRIDAY/...

TODAY AND TONIGHT...HIGH CONFIDENCE.  WEAK RIDGE OF HIGH PRESSURE
WILL KEEP WINDS/SEAS WELL BELOW SMALL CRAFT ADVISORY THRESHOLDS.

FRIDAY...MODERATE TO HIGH CONFIDENCE.  A BACKDOOR COLD FRONT AND ITS
ASSOCIATED PRESSURE RISES MAY BRING A BRIEF SURGE OF NORTHEAST WIND
GUSTS OF 25 KNOTS FRIDAY MORNING INTO MID AFTERNOON.  THIS WOULD
AFFECT MAINLY BOSTON HARBOR...POINTS NORTH AND EAST.  SINCE IT LOOKS
SHORT-LIVED NO SMALL CRAFT HEADLINES PLANNED AT THIS TIME.
HOWEVER...LATER SHIFTS MAY HAVE TO THINK ABOUT A MARINE WEATHER
STATEMENT. OTHERWISE...WINDS/SEAS SHOULD REMAIN BELOW SMALL CRAFT
THRESHOLDS BUT ENOUGH EASTERLY FETCH TO BUILD SEAS TO 4 FEET
ACROSS OUR EASTERN WATERS.

OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE.

WINDS AND SEAS REMAIN BELOW SMALL CRAFT LEVELS THROUGH THE
PERIOD. THERE MAY BE BRIEF GUSTS UP TO 25 KT AND SEAS MAY REACH
CLOSE TO 5 FT ON THE OUTER WATERS AROUND THE SUNDAY NIGHT
TIMEFRAME. LOW CLOUDS AND FOG WITH MILD...HUMID AIR MOVING ACROSS
THE COOLER OCEAN WATERS EACH OVERNIGHT INTO EARLY MORNING PERIODS
ESPECIALLY ALONG S COAST. SOME PATCHY DRIZZLE AND SPRINKLES ARE
POSSIBLE FRI AND SAT NIGHTS ACROSS THE SOUTHERN WATERS...OTHERWISE
MAINLY DRY. MAY SEE SOME SHOWER ACTIVITY MOVE INTO THE EASTERN
WATERS DURING MONDAY.

&&

.FIRE WEATHER...
TODAY...DRY WEATHER WILL CONTINUE TODAY WITH MINIMUM AFTERNOON
RELATIVE HUMIDITY VALUES DROPPING TO BETWEEN 15 AND 25 PERCENT.
WIND GUSTS WILL REMAIN WELL BELOW SMALL CRAFT ADVISORY THRESHOLDS.

FRIDAY...ANOTHER DAY OF DRY WEATHER WITH MINIMUM AFTERNOON RELATIVE
HUMIDITIES DROPPING TO BETWEEN 25 AND 35 PERCENT INLAND FROM THE
COAST.  HOWEVER...RELATIVE HUMIDITIES WILL BE HIGHER ALONG THE COAST
AS A RESULT OF A BACKDOOR COLD FRONT.  A FAIRLY STRONG WIND SHIFT
EXPECTED TO OCCUR ACROSS NORTHEAST MA FRI MORNING INTO THE
AFTERNOON...WITH BRIEF NORTHEAST WIND GUSTS OF 20 TO 30 MPH
POSSIBLE.  FURTHER INLAND WHERE RELATIVE HUMIDITY VALUES WILL BE
LOWER...WINDS WILL REMAIN BELOW FIRE WEATHER HEADLINE CRITERIA.

&&

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

&&

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



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