FXUS61 KBOX 062042
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
342 PM EST SUN DEC 6 2009
.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NEW ENGLAND TONIGHT AND MOVES OFFSHORE
MONDAY. A WEAK COLD FRONT RACES THROUGH THE REGION MONDAY NIGHT. HIGH
PRESSURE RETURNS TUESDAY...THEN A LARGE STORM WILL LIKELY AFFECT
SOUTHERN NEW ENGLAND WEDNESDAY WITH MIXED PRECIPITATION AND STRONG
WIND. COLDER THAN NORMAL AND BLUSTERY WEATHER WILL FOLLOW IN THE WAKE
OF THE STORM FOR THE END OF THE WEEK AND INTO NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
TWO AREAS OF CLOUDS DURING THE EVENING...ONE AIDED BY THE OCEAN AROUND
CAPE COD AND THE SECOND MOVING OFF THE BERKSHIRES INTO THE CT VALLEY.
WITH HIGH PRESSURE BUILDING IN TONIGHT BOTH OF THESE AREAS WILL
DIMINISH. WE FAVORED A MODIFIED VERSION OF THE RGEM SKY GRIDS WHICH
WAS THE ONLY ONE TO PICK UP ON THE CLOUDS ALONG THE EAST MASS COAST.
DRY WEATHER WITH DIMINISHING WIND. TEMPS ARE A BLEND OF MOS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...HIGH PRESSURE STARTS OVER THE REGION AND MOVES OFFSHORE.
SOUTHWEST RETURN FLOW BRINGS HIGH CLOUDS ACROSS THE REGION.
ISENTROPIC SURFACES /280K AND 285K/ SHOW LIFT AT LOW LEVELS BUT THE
AIR REMAINS DRY WITH OVER 100 MB OF LIFT REQUIRED FOR SATURATION.
BETTER MOISTURE WILL BE OVER NORTHERN NEW ENGLAND SO EXPECT THE BEST
POPS TO BE TO OUR NORTH...WITH A POSSIBILITY OF LIGHT SNOW OR RAIN
SHOWERS IN THE HILLS OF NORTHERN MASS AND SOUTHERN NH. WILL BRING
SLIGHT CHANCE POPS TO THESE NORTHERN AREAS MONDAY AFTERNOON. TEMPS AT
900 MB SUGGEST MAX TEMPS IN THE UPPER 30S/LOW 40S. MOS GUIDANCE IS IN
THE BALLPARK...WE USED A BLEND FOR THE MAX TEMP FORECAST.
MONDAY NIGHT...WEAK COLD FRONT MOVES THROUGH NEW ENGLAND...LOW
PRESSURE THEN DEVELOPS ALONG THE FRONT OFFSHORE. BROUGHT CHANCE POPS
TO THE EAST COAST EARLY AS THE OFFSHORE LOW DEVELOPS. THEN DRIER AIR
MOVES IN AS HIGH PRESSURE BUILDS IN. USED A BLEND OF MOS FOR MIN
TEMPS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL MOVE ACROSS SOUTHERN NEW ENGLAND TUESDAY BRINGING
SEASONABLY COOL...DRY WEATHER TO THE REGION.
THE NEXT LOW PRESSURE SYSTEM WILL AFFECT THE AREA WEDNESDAY. WHILE
THE MODELS HAVE THE SAME GENERAL PATTERN WITH THIS STORM...THERE ARE
SOME DISCREPANCIES REGARDING TRACK AND TIMING. THEREFORE AM GOING
TO GO WITH A BLEND OF THE AVAILABLE GUIDANCE FOR MOST FIELDS.
THE GENERAL PATTERN IS A LOW PRESSURE SYSTEM MOVING THROUGH THE
GREAT LAKES REGION INTO SOUTHWESTERN QUEBEC WITH A SECONDARY LOW
PRESSURE IN THE CAROLINAS MOVING ALONG THE COAST THROUGH NEW ENGLAND
AND INTO THE MARITIMES.
AT THIS TIME...VERTICAL TEMPERATURE PROFILES INDICATE THIS TO BE
MAINLY A RAIN EVENT. SNOW IS POSSIBLE AT THE ONSET IN MOST
LOCATIONS WITH COLD COLD AIR IN PLACE INITIALLY. SOMEWHAT WARMER
ONSHORE FLOW WILL OVERWHELM THIS COLD AIR THROUGH THE DAY ALLOWING
FOR A CHANGE TO RAIN ACROSS ALL OF SOUTHERN NEW ENGLAND. ADVISORY
LEVEL SNOWFALL MAY BE REACHED IN THE DISTANT INTERIOR WHERE IT WILL
SNOW THE LONGEST.
THE OTHER CONCERN FOR WEDNESDAY AND A PORTION OF THURSDAY WILL BE
WINDS. STRONG WINDS...PARTICULARLY ON THE CAPE AND ISLANDS...ARE
LIKELY. AN ADVISORY WILL LIKELY BE NEEDED WITH A LOW PROBABILITY OF
A HIGH WIND WARNING IN THESE AREAS. EASTERLY WINDS SHIFT TO THE
SOUTHEAST AND THEN SOUTHWEST QUICKLY WEDNESDAY EVENING. COUPLED
WITH LOW ASTRONOMICAL TIDES...THIS WILL LIMIT COASTAL FLOODING
POTENTIAL.
AS WE PROGRESS FURTHER INTO THE FUTURE THERE ARE MORE DIFFERENCES IN
THE MODELS. HOWEVER...THE GENERAL TREND INDICATES A GENERALLY ZONAL
FLOW WITH HIGH PRESSURE BUILDING INTO SOUTHERN NEW ENGLAND. THERE
IS A POSSIBILITY OF AN AREA OF LOW PRESSURE MOVING THROUGH NORTHERN
NEW ENGLAND SUNDAY...HOWEVER THIS FAR OUT IT IS A LOW CONFIDENCE
FORECAST. A GENERALLY DRY...COOLER THAN NORMAL FORECAST EXPECTED
FOR THE END OF THE WEEK THROUGH THE WEEKEND.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
TONIGHT...TWO AREAS OF CIGS AROUND 3000 FEET...ONE ALONG THE EAST
COAST AND THE OTHER MOVING OUT OF THE BERKSHIRES INTO THE CT VALLEY.
DRIER AIR AND HIGH PRESSURE BUILDING OVERHEAD SHOULD CONVINCE THE
CLOUDS TO DIMINISH EARLY TONIGHT. THE HIGH WILL ALSO BRING LIGHT
WINDS OVERNIGHT.
MONDAY...VFR WITH INCREASING CLOUDS ABOVE 10 THOUSAND FEET. ISOLATED
SNOW/RAIN SHOWERS IN FAR NORTHERN MASS AND SOUTHERN NH...MAINLY IN
THE HILLS.
MONDAY NIGHT...VFR CIGS AND WIDELY SCATTERED RAIN/SNOW SHOWERS IN
EASTERN MASS. CLEARING SKIES AFTER MIDNIGHT.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY...VFR.
WEDNESDAY...MVFR/IFR LIKELY IN WIDESPREAD RAIN. GUSTY SFC WINDS.
THURSDAY AND FRIDAY...CONDITIONS IMPROVE TO VFR BY THURSDAY AFTERNOON.
STRONG SFC WINDS CONTINUE.
&&
.MARINE...
TONIGHT...DIMINISHING WINDS AND SEAS. LINGERING SMALL CRAFT HEADLINES
ON MOST WATERS THIS EVENING AND ON THE EASTERN WATERS THROUGH
MIDNIGHT.
MONDAY...LIGHT WINDS AND SEAS.
MONDAY NIGHT...LOW PRESSURE DEVELOPS OVER THE GULF OF
MAINE...INCREASING THE PRESSURE GRADIENT OVER THE SOUTHEAST WATERS.
THIS WILL BRING WINDS NEAR SMALL CRAFT LEVELS...MAINLY GUSTS. THESE
WINDS DIMINISH LATE.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
WINDS AND SEAS BELOW SMALL CRAFT CRITERIA THROUGH TUE NIGHT. WINDS
WILL INCREASE VERY EARLY WED MORNING NEARING SMALL CRAFT CRITERIA ON
THE SOUTHWESTERN WATERS. EASTERLY GALES LIKELY WED SHIFTING TO THE
SOUTHWEST WED NIGHT. WESTERLY GALES PROBABLE THU AND FRI.
&&
.EQUIPMENT...
GLOUCESTER NWR TRANSMITTER IS OFF THE AIR. RTS UNKNOWN.
WE ARE WORKING ON THE PROBLEM. JOHNSTON/PROVIDENCE NWR TRANSMITTER
IS BACK ON THE AIR BUT ON LOW POWER...SOME SOUTH COASTAL LOCATIONS
MAY BE UNABLE TO RECEIVE THE SIGNAL. MORE MAINTENANCE WILL BE DONE ON
MONDAY TO RETURN THIS STATION TO FULL POWER. IN THE MEANTIME...PLEASE
SEE OUR WEBSITE... WWW.WEATHER.GOV/BOSTON FOR WEATHER INFORMATION.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EST MONDAY FOR ANZ231-232-250-
251-254-255.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ233>235-237-256.
&&
$$
SYNOPSIS...WTB
NEAR TERM...WTB
SHORT TERM...WTB
LONG TERM...RLG
AVIATION...WTB/RLG
MARINE...WTB/RLG
EQUIPMENT...RLG
