FXUS61 KBOX 242055
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
355 PM EST THU DEC 24 2009
.SYNOPSIS...
LOW PRESSURE WILL TRACK UP THE EASTERN SEABOARD THIS WEEKEND...BRINGING
A PERIOD OF WINTRY WEATHER INLAND WITH MAINLY RAIN ALONG THE COAST.
THE LOW AND ITS PRECIPITATION SHOULD DEPART SUNDAY MORNING INTO THE
EARLY AFTERNOON. WEAK LOW PRESSURE WILL BRING A CHANCE OF LIGHT SNOW
TO SOUTHERN AREAS ON MONDAY. VERY COLD AND BLUSTERY WEATHER WILL
FOLLOW IN THE WAKE OF THIS LOW MONDAY NIGHT INTO WEDNESDAY. A COASTAL
STORM MAY BRING MORE WINTRY PRECIPITATION TO THE REGION AROUND NEW
YEARS EVE.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A LEFTOVER SHORT WAVE MOVING AROUND THE POLAR VORTEX MOVING E OF
CAPE COD CONTINUED TO PRODUCE SOME OCEAN ENHANCED SNOW BANDS LATE THIS
MORNING. COULD SEE THE MOISTURE FEEDER ROTATING ACROSS THE GULF OF
MAINE INTO MA BAY ON THE WATER VAPOR SATELLITE.
LATEST RADAR TRENDS INDICATE THAT OCEAN ENHANCED SNOW/RAIN SHOWERS
HAVE BEGUN TO DIMINISH IN INTENSITY. THIS TREND IS EXPECTED TO
CONTINUE INTO EARLY AFTERNOON. LIKELY POPS DIMINISH TO CHANCE FOR
EARLY THIS AFTERNOON ALONG/NEAR CAPE AND ISLANDS.
OTHERWISE...POLAR VORTEX MOVING OUT ACROSS GEORGES BANK. LINGERING
LOW LEVEL MOISTURE KEPT CLOUDS AROUND THIS MORNING. BUT WITH THE LOW
MOVING AWAY AND CANADIAN HIGH PRESSURE BUILDING SOUTH ACROSS SOUTHERN
NEW ENGLAND...AND WITH DRYING ABOVE 925 MB...WE SHOULD SEE THE CLOUDS
DECREASE THROUGH THE DAY. DECREASING CLOUDS ALREADY NOTED IN PORTIONS
OF WESTERN MA AND NORTH CENTRAL CT.
LOW LEVEL TEMPS SUPPORT MAX TEMPS AROUND 40F. TEMPERATURES ARE A
BLEND OF NAM AND GFS MOS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
HIGH PRESSURE IN CONTROL MOST OF THE PERIOD...DRY WEATHER WITH A
DEVELOPING NORTHEAST FLOW OFF MASSACHUSETTS BAY. HIGH CLOUDS SHOULD
INCREASE THROUGH THE DAY...ESPECIALLY IN THE AFTERNOON/EVENING...AS
THE MIDWEST STORM PUSHES ITS CLOUD SHIELD EAST.
DEWPOINTS IN THE MID TEENS INLAND TO NEAR 30 CAPE/ISLANDS...THIS
SHOULD BE THE LIMIT FOR NIGHTTIME MIN TEMPS. TEMPS AT 925 MB REMAIN
AROUND -2C TO -3C FRIDAY...SIMILAR TO TODAY...SO EXPECT MAX TEMPS
XMAS DAY IN THE MID 30S TO AROUND 40.
IF THERE IS ANY UNCERTAINTY IN THIS PART OF THE FORECAST IT WOULD BE
THE POTENTIAL FOR MARINE INFLUENCE AT LOW LEVELS ESPECIALLY IN
EASTERN MASS. IF THE NORTHEAST FLOW IS ABLE TO MAINTAIN ENOUGH
MOISTURE IN THE LOWEST LAYERS IT COULD MAKE XMAS DAY CLOUDIER WITH
POTENTIAL DRIZZLE ALONG THE SOUTH COAST. LOW CONFIDENCE IN THIS
SCENARIO SO WE WILL GO WITH THE DRIER FORECAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
THE MAIN FORECAST CONCERNS DURING THE LONG TERM PERIOD REVOLVE AROUND
THE POTENTIAL FOR ICING FRIDAY NIGHT THROUGH SUNDAY MORNING. A STRONG
CLOSED LOW WILL MOVE TOWARD SOUTHERN NEW ENGLAND FRIDAY NIGHT THROUGH
THE WEEKEND. VARIOUS MODELS STILL DIFFER IN THE TIMING OF HEAVIEST
PRECIPITATION WITH THIS SYSTEM. HOWEVER...THE GENERAL CONSENSUS IS
THAT THE STEADIEST PRECIPITATION WILL OCCUR SATURDAY NIGHT INTO
SUNDAY MORNING.
LITTLE IN THE WAY OF MEASURABLE PRECIPITATION IS EXPECTED TO OCCUR
FRIDAY NIGHT AS THE FORCING ASSOCIATED WITH THE UPPER LOW REMAINS
WELL TO THE WEST AND RIDGING THROUGHOUT THE COLUMN DOMINATES OVER
SOUTHERN NEW ENGLAND. HOWEVER...FORECAST SOUNDINGS DO SHOW THE LOW
LEVELS BECOMING SATURATED BENEATH THE MID LEVEL DRY LAYER. BUFKIT
SOUNDINGS HAVE A DRIZZLE/FREEZING DRIZZLE LOOK TO THEM FOR FRIDAY
NIGHT. WHILE NOT MUCH IN THE WAY OF MEASURABLE PRECIPITATION IS
EXPECTED TO OCCUR...FREEZING DRIZZLE CAN BE MORE DANGEROUS THAN A
FOOT OF SNOW. WE WILL HAVE TO CAREFULLY KEEP AN EYE ON THIS THREAT
OVER THE NEXT 24 HOURS...AS LOW LEVEL TEMPS STILL REMAIN IN QUESTION
AND POSSIBLE SEEDER-FEEDER PROCESS COULD PRECLUDE WIDESPREAD
FZDZ...BUT THAT DOESN/T LOOK QUITE AS LIKELY RIGHT NOW. THE BEST
CHANCE FOR ANY FREEZING DRIZZLE WILL BE WEST OF I-95...WITH PERHAPS
THE MONADNOCKS AND WORCESTER HILLS BEING A MORE LIKELY SPOT GIVEN
UPSLOPE POTENTIAL DUE TO THE EASTERLY LOW LEVEL WINDS. MUCH OF THE
COASTAL PLAIN SHOULD REMAIN JUST ABOVE FREEZING.
STEADY PRECIPITATION WILL ATTEMPT TO WORK INTO SOUTHERN NEW ENGLAND
DURING THE DAY ON SATURDAY...BUT WILL BE SLOW TO DO SO GIVEN THE
WELL-AMPLIFIED RIDGE IN PLACE OVER EASTERN NEW ENGLAND. AS FAR AS
POPS GO...ONLY WENT AS HIGH AS CHANCE FOR THE EASTERN ZONES BY LATE
IN THE DAY...WITH LIKELY IN THE FAR WEST. MUCH OF THE PRECIP DURING
THE DAY SHOULD BE IN THE FORM OF RAIN...BUT IT GETS TRICKY FOR THE
INTERIOR AS THICKNESSES WILL BE MARGINAL. COULD SEE A MIX OF
SNOW/SLEET/FREEZING RAIN AND EVEN ALL RAIN AT TIMES. BEST CHANCE FOR
FREEZING RAIN WILL BE ON THE EASTERN SLOPES OF THE BERKS.
OVERALL...NOT EXPECTING HEAVY PRECIP DURING THE DAY SATURDAY.
WENT WITH CATEGORICAL POPS FOR SATURDAY NIGHT AS MAIN SLUG OF
RAINFALL MOVES ON IN WITH THE SELY LLJ. AS OF RIGHT NOW...IT LOOKS AS
THOUGH ENOUGH RELATIVELY WARM AIR WILL FLOOD NORTHWARD TO PRECLUDE A
MAJOR ICE EVENT. HOWEVER...WITH THAT SAID...WE WILL HAVE TO WATCH
SOME ESPECIALLY PRONE LOCATIONS SUCH AS THE BERKS...MONADS...AND THE
WORCESTER HILLS FOR SOME POCKETS OF ENHANCED ICING. MOST OTHER AREAS
WILL BE A PLAIN COLD RAIN. THIS COULD SPELL SOME URBAN AND POOR
DRAINAGE FLOODING AS A LOT OF STORM DRAINS ARE LIKELY STUFFED WITH
SNOW FROM THE PREVIOUS STORM. WE AREN/T EXPECTING ANY SIGNIFICANT
FLOODING ISSUES AT THIS TIME AS THE CURRENT SNOWPACK SHOULD BE ABLE
TO ABSORB MUCH OF THE RAINFALL...WHICH IS EXPECTED TO BE AROUND AN
INCH OR SO.
DRY SLOT QUICKLY MOVES IN ON SUNDAY...ENDING THE PRECIP FROM WEST TO
EAST IN THE MORNING...POSSIBLY EARLY AFTERNOON EAST COAST OF MASS.
SUNDAY AFTERNOON COULD ACTUALLY BE HALFWAY DECENT...WITH WARMING
TEMPS AND SUN IN THE DRY SLOT. IF ALL BREAKS RIGHT...WOULDN/T BE
SURPRISED TO SEE SUNSHINE WITH TEMPS AROUND 50F ON THE COASTAL PLAIN
SUNDAY AFTERNOON.
NEXT SHORT WAVE MOVES ACROSS THE REGION ON MONDAY. FOR NOW...WE HAVE
A CHANCE OF LIGHT SNOW GOING...MAINLY FOR SOUTHERN ZONES. THERE IS A
LOW PROB THAT WE COULD HAVE A 1-3 INCH SNOW EVENT OUT OF THIS...BUT
IT MAY STAY JUST SOUTH OF US. VERY COLD AND WINDY FOR MONDAY NIGHT
THROUGH EARLY WED IN WAKE OF ARCTIC FRONT. WIND ADVISORY EVENT
POSSIBLE TUE...ALONG WITH NASTY WIND CHILLS.
THE MODELS HAVE CONTINUED TO ADVERTISE A SIGNIFICANT COASTAL SYSTEM
AFFECTING MUCH OF SOUTHERN NEW ENGLAND FOR NEW YEARS EVE...AND THIS
CONTINUES TO BEAR WATCH.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
TODAY...
NOTING NORTHERN EDGE OF MVFR CLOUD 2000FT SHIELD SHIFTING S OF THE
MA/NH BORDER AT 18Z. THIS CLOUD SHIELD SHOULD ADVANCE S REACHING BOS-
ORH AROUND 20-21Z. LEFTOVER SCT030 UNTIL 00Z.
TONIGHT...VFR. LOCS SE OF I95 AND S OF BOS SHOULD NOTE MVFR CEILINGS
IMPROVING TO VFR BY 02Z. MODERATE CONFIDENCE MVFR CEILINGS IMPROVE TO
VFR ON THE CAPE AND ISLANDS AROUND 06Z...EXCEPT BY 12Z ACK.
FRIDAY...EARLY MORNING MVFR CEILINGS AROUND 2000 FT ACK. OTRW VFR
WITH INCREASING AFTERNOON/EVENING CLOUDS AT 25K FEET.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
FRIDAY NIGHT...LOW CONFIDENCE IN CIGS...BUT FORECAST SOUNDINGS SHOW
POSSIBLE MVFR/IFR DEVELOPING IN DZ AT THE COAST AND FZDZ INTERIOR.
SATURDAY...PROBABLY MVFR TO START...BUT IT COULD BE IFR...ESPECIALLY
AT ORH. LOW CONFIDENCE.
SATURDAY NIGHT...IFR CONDITIONS EXPECTED IN MAINLY RAIN...ALTHOUGH A
WINTRY MIX POSSIBLY AT ORH AND MAYBE MHT.
SUNDAY...MVFR/IFR CONDITIONS IMPROVE TO VFR AROUND MIDDAY.
MONDAY...VFR...BUT POSSIBLE MVFR IN SNOW SHOWERS.
TUESDAY...VFR...GUSTY NW WINDS.
&&
.MARINE...
TODAY...
NORTHWEST WINDS BECOME NORTH WITH GUST POTENTIAL TO 25 KT...EXCEPT
GUSTS TO 20 KNOTS BOSTON HARBOR AND NARRAGANSETT BAY. HAVE INCLUDED
MENTION OF RAIN/SNOW SHOWERS THROUGH THE MORNING WITH REDUCED VSBYS.
TONIGHT...
NORTH TO NORTHEAST WINDS DIMINISH AS CANADIAN HIGH PRES BUILDS INTO
NEW ENGLAND. SEAS REMAIN AT OR ABOVE 5 FEET ON THE OUTER WATERS
THROUGH THE NIGHT.
FRIDAY...
LIGHT NORTHEAST TO EAST WINDS. SEAS STILL AT OR ABOVE 5 FEET...MAINLY
ON OUTER WATERS.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
FRIDAY NIGHT...SMALL CRAFT WINDS AND SEAS.
SATURDAY-SUNDAY...EAST TO SOUTHEAST WINDS MAY INCREASE TO GALE
SATURDAY NIGHT AND CONTINUE INTO SUNDAY.
MONDAY...SMALL CRAFT WINDS AND SEAS.
MONDAY NIGHT AND TUE...NW GALES PROBABLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR
ANZ231>235-237-256.
SMALL CRAFT ADVISORY UNTIL 11 AM EST FRIDAY FOR ANZ250-251-254-
255.
&&
$$
SYNOPSIS...EKSTER
NEAR TERM...NMB
SHORT TERM...NMB
LONG TERM...EKSTER
AVIATION...EKSTER/STRAUSS/NMB
MARINE...EKSTER/NMB
