Area Forecast Discussion
Issued by NWS Boston, MA

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FXUS61 KBOX 021932
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
332 PM EDT SAT MAY 2 2015

.SYNOPSIS...
PROGRESSIVELY WARMER WEATHER IS EXPECTED THIS WEEKEND ESPECIALLY
AWAY FROM THE COAST. DRY CONDITIONS DOMINATE WITH THE EXCEPTION OF A
FEW SHOWERS POSSIBLE SUNDAY AFTERNOON ACROSS CENTRAL-EASTERN
MASSACHUSETTS AND RHODE ISLAND. HIGH PRESSURE BUILDS OVER THE REGION
DURING EARLY NEXT WEEK. A COLD FRONT SWEEPS SOUTH ACROSS THE REGION
TUESDAY AND THEN STALLS SOUTH OF NEW ENGLAND MIDWEEK. HIGH PRESSURE
REBUILDS WITH DRY AND WARMING WEATHER THE REMAINDER OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

330 PM UPDATE...

THIS EVENING...

SPECTACULAR WEATHER CONTINUES AT 3 PM WITH LIGHT WINDS AND TEMPS
WELL INTO 60S WITH LOW 70S IN THE CT RVR VLY.  AT THE COAST
CONSIDERABLY COOLER WITH SEABREEZES KEEPING TEMPS IN THE U40S TO LOW
50S! STRATUS/LOW CLOUDS ARE NOW JUST CONFINED TO THE SOUTH COAST OF
CAPE ANN AND EASTERN NANTUCKET TO CHATHAM AREA AND SEAWARD. THESE
LOW CLOUDS WILL CONTINUE TO ERODE AND MOVE FARTHER OFFSHORE AS LOW
LEVEL FLOW TURNS TO THE SSW THIS EVENING.

COOL AIR ALOFT YIELDING DIURNAL CLOUDS OVER THE HIGHER TERRAIN. KENX
RADAR DETECTING AN ISOLATED SHOWER IN THE EAST SLOPES OF THE BERKS
AT 3 PM BUT WITH DEW PT DEPRESSIONS AROUND 30 DEGS ANY PRECIP
REACHING THE GROUND WILL LIKELY JUST BE SPRINKLES. THIS ACTIVITY
WILL ERODE TOWARD SUNSET. OTHERWISE DRY WEATHER PREVAILS.

OVERNIGHT...

ANOTHER COOL NIGHT WITH RIDGE AXIS OVER THE REGION PROVIDING LIGHT
WINDS COUPLED WITH A DRY AIRMASS...ALTHOUGH NOT AS CHILLY AS LAST
NIGHT AS SEA BREEZES ADVECTING DEW PTS IN THE L40S INLAND. IN
ADDITION SSW SURFACE WINDS IN THE COASTAL PLAIN WILL PRECLUDE TEMPS
FROM FREE FALLING HERE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...

SUNDAY...

ANY MORNING FOG WILL NOT BE AS WIDESPREAD AS THIS MORNING. THUS ONLY
PATCHY FOG EXPECTED. STRONG MAY SUNSHINE WILL QUICKLY BOOST TEMPS
INTO THE U60S AND L70S BY AFTERNOON...MID 70S CT RVR VLY.

WILL LIKELY SEE ISOLATED TO SCATTERED AFTERNOON SHOWERS BETWEEN 3 PM
AND 7 PM WITH THE GREATEST RISK ACROSS CENTRAL-EASTERN MA INTO RI
AND POSSIBLY NORTHEAST CT. CULPRIT IS A LOW AMPLITUDE SHORT WAVE
TROUGH ACROSS THIS REGION WITH COOL AIR ALOFT. THIS RESULTS IN
STEEPENING MID LEVEL LAPSE RATES OF ABOUT 6.5CM/KM. DEW PTS REMAIN
FAIRLY DRY IN THE 40S TO PERHAPS NEAR 50...WHICH LIMITS SB CAPES TO
A FEW HUNDRED JOULES. NEVERTHELESS WEAK INSTABILITY COMBINED WITH
CYCLONIC FLOW ALOFT SHOULD BE SUFFICIENT FOR ISOLATED TO SCATTERED
SHOWERS ACROSS THE MENTIONED AREA. SHEAR IS LIMITED AT 15-25 KT SO
WITH WEAK INSTABILITY NOT EXPECTING ANY SEVERE WEATHER. WORSE CASE
SCENARIO IS FOR ISOLATED THUNDER WITH PERHAPS PEA SIZE HAIL GIVEN
COLD TEMPS ALOFT AND MAYBE GUSTY WINDS UP TO 35 MPH WITH INVERTED /
SOUNDING AS TEMPS CLIMB TO AROUND 70 AND DEW PTS ONLY IN THE 40S.

MODELS SEEM TO BE TARGETING NORTHEAST MA WITH PERHAPS SEABREEZE
INTERACTION ENHANCING LOW LEVEL CONVERGENCE AND HIGHER DEW
PTS/INSTABILITY. OTHERWISE NICE WEATHER MUCH OF THE DAY WITH JUST A
FEW SHOWERS AND ISOLATED TSTM 3 PM TO 7 PM.

PGRADIENT REMAINS WEAK ENOUGH TO SUPPORT ANOTHER ROUND OF SEABREEZES
THUS COOLER AT THE SHORE.

SUNDAY NIGHT...

ANY LEFTOVER ISOLATED/WIDELY SCATTERED SHOWERS DISSIPATE BY 8-9 PM
WHICH GIVES WAY TO A PLEASANT EVENING/NIGHT AND NOT AS COOL WITH
MINS ONLY 45 TO 50! SSW WINDS WILL LIMIT ANY PATCHY FOG TO THE SOUTH
COAST.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

HIGHLIGHTS...

* ABOVE NORMAL TEMPERATURES EXPECTED THROUGHOUT THE WEEK
* COLD FRONT MOVES THROUGH TUESDAY WITH SHOWERS POSSIBLE
* POTENTIAL FOR A BACK DOOR COLD FRONT SATURDAY

MODELS ARE IN GOOD AGREEMENT THROUGH MUCH OF THE LONG TERM PORTION
OF THE FORECAST.  THERE ARE DISCREPANCIES AS WE GET TOWARDS THE END
OF NEXT WEEK WITH THE STRENGTH OF THE HIGH JUST TO THE EAST OF
SOUTHERN NEW ENGLAND AND THE POTENTIAL FOR A BACK DOOR COLD FRONT TO
MOVE THROUGH THE REGION SATURDAY.

LOOKS LIKE A PICTURE PERFECT WEEK FOR MUCH OF THE WEEK WITH HIGH
PRESSURE AND AN UPPER LEVEL RIDGE ACROSS SOUTHERN NEW ENGLAND.  THE
TWO POTENTIAL EXCEPTIONS TO THIS ARE A COLD FRONT MOVING THROUGH
TUESDAY AND A POSSIBLE BACK DOOR COLD FRONT MOVING INTO THE REGION
SATURDAY. OTHERWISE...TEMPERATURES LOOK TO BE WELL ABOVE NORMAL WITH
HIGHS MOSTLY IN THE 70S AWAY FROM SHORE WITH A POSSIBILITY OF LOW
80S ON MONDAY.

THE COLD FRONT TUESDAY WILL LIKELY BRING SOME SHOWERS.  INSTABILITY
LOOKS MARGINAL AT THIS POINT SO NOT CURRENTLY EXPECTING ANY THUNDER
WITH THESE SHOWERS.

THE BACK DOOR COLD FRONT SATURDAY IS CONFINED TO THE ECMWF SOLUTION
WITH NO SIGN OF IT IN THE GFS.  SO SATURDAY IS A SOMEWHAT LOW
CONFIDENCE FORECAST.  IF THE ECMWF IS RIGHT...COOLER AND CLOUDIER
WEATHER WITH SOME RAIN POSSIBLE.  IF THE GFS VERIFIES...ANOTHER
BEAUTIFUL SPRING DAY.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

.SHORT-TERM /THROUGH SUNDAY/...

THRU 00Z...HIGH CONFIDENCE. VFR WITH LIGHT ONSHORE SEABREEZES. LOW
CLOUDS/STRATUS WILL LURK JUST OFFSHORE BUT SHOULD MOVE FARTHER
OFFSHORE THIS EVENING AS WINDS BECOME SSW. DIURNAL CLOUDS AT
BKN060-080 OVER WESTERN NEW ENGLAND MAY YIELD A BRIEF SHOWER TIL
SUNSET.

AFTER 00Z...HIGH CONFIDENCE. VFR WITH LIGHT SSW WIND. LOW RISK OF
PATCHY MVFR IN FOG 06Z-12Z.

SUNDAY...HIGH CONFIDENCE FOR VFR. SCATTERED SHOWERS POSSIBLY IN
MVFR/VFR 19Z- 23Z WITH GREATEST RISK CENTRAL-EASTERN MA INTO RI.
WINDS...LIGHT SSW.

SUNDAY NIGHT...HIGH CONFIDENCE FOR VFR. PATCHY MVFR FOG POSSIBLE.
LIGHT SSW WINDS PREVAIL.

KBOS TAF...HIGH CONFIDENCE IN TAF. SEABREEZE MAKES IT TURN TO THE
SOUTH THIS EVENING. LOW RISK OF A FEW AFTERNOON SHOWERS 19Z-23Z
SUNDAY. SEA BREEZE ONCE AGAIN TOMORROW.

KBDL TAF...HIGH CONFIDENCE IN TAF.

OUTLOOK...MONDAY THROUGH THURSDAY...

HIGH CONFIDENCE.  MAINLY VFR.  LOW PROBABILITY OF BRIEF MVFR/IFR
CONDITIONS IN SCT -SHRA TUESDAY.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

.SHORT-TERM /THROUGH SUNDAY NIGHT/...

THIS EVENING AND OVERNIGHT...

STRATUS/FOG OVER EASTERN MA WATERS CONTINUES TO DISSIPATE AND MOVE
FURTHER SEAWARD AS RETURN FLOW BECOMES ESTABLISHED. PATCHY FOG MAY
REDEVELOP LATE TONIGHT INTO SUN MORNING.

SUNDAY...

SSW WINDS MAY INCREASE TO ABOUT 15 KT IN THE AFTERNOON OVER CAPE COD
WATERS. OTHERWISE ANY MORNING FOG QUICKLY BURNS OFF YIELDING GOOD
VSBY. DRY WEATHER GIVES WAY TO SCATTERED AFTERNOON SHOWERS MAINLY
NORTH SHORE MASSACHUSETTS.

SUN NIGHT...

LIGHT SSW WINDS. GOOD VSBY WITH ANY EVENING SHOWERS ENDING RAPIDLY.

OUTLOOK...MONDAY THROUGH THURSDAY...

MONDAY...HIGH CONFIDENCE. MARGINAL SCA CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS GUSTING TO AROUND 20 KTS AND SEAS BUILDING TO
AROUND 5 FEET AHEAD OF A COLD FRONT MOVING THROUGH THE WATERS
TUESDAY.

TUESDAY...MODERATE CONFIDENCE. WINDS AND SEAS DIMINISH AS HIGH
PRESSURE BUILDS IN BEHIND THE COLD FRONT CROSSING THE WATERS
EARLY.

WEDNESDAY AND THURSDAY...HIGH CONFIDENCE. QUIET BOATING WEATHER
WITH HIGH PRESSURE OVER THE WATERS.

&&

.FIRE WEATHER...
THE BIGGEST FIRE WEATHER CONCERN IS FOR MONDAY.  MINIMUM AFTERNOON
RELATIVE HUMIDITY VALUES DROPPING TO 25-30 PERCENT WITH AFTERNOON
WIND GUSTS OF 20 TO PERHAPS 25 MPH. APPEARS JUST BELOW CRITERIA FOR
ANY FIRE WEATHER HEADLINES...BUT WILL CONTINUE TO MONITOR SINCE ITS
BEEN SO DRY AS OF LATE.

&&

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

&&

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



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