Area Forecast Discussion
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000
FXUS61 KBOX 050905
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
505 AM EDT WED AUG 5 2015

.SYNOPSIS...
A FEW SHOWERS OR THUNDERSHOWERS ARE POSSIBLE THIS AFTERNOON...FOLLOWED
BY DRIER WEATHER INTO THURSDAY. A PERIOD OF UNSETTLED WEATHER IS
POSSIBLE LATE FRIDAY INTO THIS WEEKEND...BUT CONFIDENCE REMAINS
LOW REGARDING THE TIMING AND COVERAGE OF ANY POTENTIAL WET
WEATHER.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CONVECTION CONTINUES WITHIN A BAND OF HIGHER THETA-E/LOWER STATIC
STABILITY TO THE S OF A WEAKENING COLD FRONT CURRENTLY SITUATED
NEAR THE S COAST THIS MORNING. BULK OF THE ACTIVITY SHOULD REMAIN
OUTSIDE OF THE BOX/OKX COASTAL WATERS DUE TO SLIGHT TURNING TOWARD
THE LOWER STABILITY FURTHER S. EVEN THE CI/ANVIL REMAINS OFFSHORE.

OTHERWISE...WITH CYCLONIC FLOW CONTINUES ACROSS MOST OF NEW
ENGLAND TODAY WITH YET A FINAL STRONG SHORTWAVE EXPECTED TO MOVE
ACROSS THE REGION DURING THE LATE MORNING/AFTERNOON HOURS. THIS IS
WITHIN A REGIME WHERE H5 HEIGHTS ARE GENERALLY 2-3 STD DEVIATIONS
BELOW NORMAL AND H5 TEMPS DROP BETWEEN -13C AND -15C. DRIER AIR
DOES CONTINUE TO INVADE THE COLUMN BEHIND THE EXITING FRONT...SO
THIS LIMITS THE LAPSE RATES IN SPITE OF THE COLD TEMPS ALOFT.
STILL...LOOKS LIKE ENOUGH DIURNALLY DRIVEN AFTERNOON INSTABILITY
TO SUPPORT SOME MODEST CONVECTIVE SHRA/T-STORMS. THE COLD TEMPS
SUGGEST RISK FOR SMALL HAIL...BUT THE DRIER AIR NEAR THE SFC COULD
SUPPORT SOME GUSTY WINDS AS WELL. THEREFORE...HAVE ADDED THIS
WORDING TO THE FORECAST WITH THIS UPDATE. HIGHEST RISK WILL BE
N...WHERE COLDEST TEMPS AND OVERALL MOISTURE RESIDES...HENCE THE
MARGINAL RISK ACROSS NRN NEW ENGLAND. THEREFORE...FOCUS IS N OF
THE MASS PIKE...BUT RISK IS NON-ZERO EVERYWHERE. WITH THE DRY
AIR...NOT EXPECTING ACTIVITY TO BE AS STRONG OR WIDESPREAD AS
TUESDAY...BUT STILL WORTH WATCHING THE SKIES THROUGH THE DAY.

OTHERWISE...TEMPS REMAIN WARM TODAY AS THE COLDEST AIR IN THE LOW
LVLS STILL LAGS THE FRONT A BIT. EXPECT HIGHS MAINLY IN THE MID-
UPPER 80S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...
SUSPECT ANY SHOWERS/STORMS WILL DISSIPATE RATHER QUICKLY AFTER
SUNSET...AS IT WILL REQUIRE THE SFC WARMING TO MAINTAIN. SUSPECT
AN END BETWEEN 00Z-02Z. WITH SKIES CLEARING AND SFC PRES GRADIENT
WEAKENING SOMEWHAT...TEMPS ARE LIKELY TO COOL INTO THE 50S BY THE
EARLY MORNING HOURS. CERTAINLY MUCH MORE COMFORTABLE THAN PREVIOUS
NIGHTS.

THU...
WEAK RIDGE OF HIGH PRES WILL BUILD ACROSS THE REGION. IN SPITE OF
LAST BIT OF CYCLONIC CURVATURE ALOFT...SUSPECT MAINLY DRY
CONDITIONS AS BEST LIFT/MOISTURE REMAINS WELL TO THE N. H85 TEMPS
SLIGHTLY BELOW NORMAL SUGGESTS HIGHS BELOW NORMAL. MAINLY THE LOW
80S.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...

* UNSETTLED WEATHER REMAINS POSSIBLE FRIDAY INTO THIS WEEKEND
* TEMPERATURES TRENDING BELOW NORMAL THROUGH MOST IF NOT THE ENTIRE
  PERIOD

OVERVIEW AND MODEL PREFERENCES...

TREND OF THE 05/00Z GUIDANCE IS TO TAKE A COASTAL LOW PRESSURE
FARTHER OFFSHORE THAN PREVIOUS RUNS. ECMWF REMAINS A LITTLE
FASTER...AND ALSO TRACKS CURVES THIS LOW PRESSURE CLOSER TO SHORE
LATER THIS WEEKEND THAN THE GFS. CONFIDENCE IS GROWING IN A DRIER
FORECAST...AT LEAST FOR FRIDAY...OWING TO THE CONSENSUS TREND
OFFSHORE. STILL NEED TO RESOLVE DETAILS FOR SATURDAY. SINCE THE
GUIDANCE HAS NOT BEEN VERY CONSISTENT WITH THIS STORM OVER THE
PAST FEW DAYS...WILL STICK WITH THE CONSENSUS APPROACH FOR NOW.

PATTERN SHIFTS FROM A CLOSED MID LEVEL LOW OVER EASTERN CANADA...
TO A FLATTER PATTERN EARLY NEXT WEEK...BEFORE ANOTHER TROUGH
ARRIVES TOWARD MID WEEK.

DETAILS...

THURSDAY NIGHT THROUGH SATURDAY...COASTAL LOW PRESSURE EXPECTED TO
MOVE SLIGHT FARTHER OFFSHORE THAN PREVIOUSLY THOUGHT. THIS SHOULD
BE FAR ENOUGH TO KEEP MOS OF SOUTHERN NEW ENGLAND DRY. GREATEST
RISK FOR SHOWERS WILL BE TOWARDS THE SOUTH COAST...AND ESPECIALLY
CAPE COD AND THE ISLANDS. DID NOT HAVE ENOUGH CONFIDENCE IN THE
DETAILS TO GO AS DRY AS SOME OF THE GUIDANCE WAS SUGGESTING. WILL
SIMPLY TREND THE FORECAST RAINFALL CHANCES DOWN AT THIS TIME.

SUNDAY THROUGH WEDNESDAY...MUCH OF THIS FORECAST CONTINUES TO
DEPEND UPON THE FRI-SAT PATTERN SETS UP. AT THIS POINT...LOOKS LIKE
IT SHOULD BE MAINLY DRY BUT COOL ON SUNDAY. MODELS SIGNALING
ANOTHER SERIES OF COLD FRONTS COMBINED WITH A MID LEVEL LONGWAVE
TROUGH EARLY NEXT WEEK. MAY SEE PERIODS OF SCATTERED SHOWERS FROM
TIME TO TIME DURING THIS TIMEFRAME...BUT LOW CONFIDENCE ON TIMING
AND PLACEMENT REMAINS.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT-TERM /THROUGH THURSDAY/...

THROUGH 12Z...HIGH CONFIDENCE.
MAINLY VFR AND DRY. A FEW LOW CLOUDS/FOG MAINLY CAPE/ISLANDS.

TODAY...MODERATE CONFIDENCE.
MAINLY VFR THROUGHOUT THE DAY...ALTHOUGH SOME SCT SHRA/TSRA WITH
SMALL HAIL AND GUSTY WINDS ARE POSSIBLE THIS AFTERNOON. NOT AS
WIDESPREAD AS YESTERDAY. W WINDS WITH GUSTS APPROACHING 20 KT AT
TIMES.

TONIGHT INTO THU...HIGH CONFIDENCE.
WEAK HIGH PRES WILL SLOWLY BUILD ACROSS THE REGION. MAINLY VFR
CONDITIONS EXPECTED.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF...LOW CONFIDENCE IN A
SHOWER OR STORM THIS AFTERNOON.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...

THURSDAY NIGHT THROUGH SATURDAY...LOW CONFIDENCE ON TIMING AND
COVERAGE...HIGHER CONFIDENCE ON TRENDS. MVFR-IFR CONDITIONS IN
AREAS OF RAIN SOMETIME DURING THIS PERIOD. VFR BEFORE AND AFTER
PERIODS OF RAIN.

SUNDAY...LOW CONFIDENCE MAINLY FOR TIMING. MAY SEE LEFTOVER SHOWERS
WITH BRIEF MVFR CONDITIONS EARLY...THEN VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT-TERM /THROUGH THURSDAY/...

THROUGH TODAY...MODERATE CONFIDENCE.
W WINDS GENERALLY REMAIN BELOW SCA CONDITIONS...WITH SEAS
GRADUALLY RECEDING THROUGH THE MORNING. SMALL CRAFT ADVISORIES
REMAIN IN PLACE THROUGH MID MORNING ALONG S WATERS...BUT WILL
LIKELY BE GONE BY MID DAY. A FEW SHOWERS OR T-STORMS POSSIBLE
MAINLY NEAR COASTLINES THIS AFTERNOON.

TONIGHT INTO THU...HIGH CONFIDENCE.
WEAK HIGH PRES BRINGS MAINLY QUIET BOATING WEATHER TO THE REGION.

OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...

THURSDAY NIGHT...HIGH CONFIDENCE. WINDS AND SEAS BELOW SMALL
CRAFT CRITERIA. LOCALLY REDUCED VSBYS IN LIGHT RAIN THU NIGHT.

FRIDAY THROUGH SUNDAY...MODERATE CONFIDENCE. EASTERLY WINDS GUSTING
UP TO 20 KT. WITH ONSHORE WINDS...SEAS LOOK TO BUILD UP TO 5-6 FT
HIGHEST ACROSS THE EASTERN OUTER WATERS. RAIN POSSIBLE FRIDAY
NIGHT THROUGH SATURDAY NIGHT...LIMITING VISIBILITIES AT TIMES...
THEN SHOULD IMPROVE DURING SUNDAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR ANZ235-
     237-254>256.

&&

$$
SYNOPSIS...BELK/DOODY
NEAR TERM...DOODY
SHORT TERM...DOODY
LONG TERM...BELK
AVIATION...BELK/DOODY
MARINE...BELK/DOODY


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