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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 100804
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
404 AM EDT MON MAR 10 2014

.SYNOPSIS...
AN ACTIVE POLAR JET STREAM WILL BRING A FEW BOUTS OF CLOUDS AND SNOW
SHOWERS OVER THE REGION THIS MORNING AND AGAIN LATE TONIGHT. AVERAGE
TEMPERATURES RETURN TO THE REGION TODAY WITH TEMPERATURES RISING
INTO THE 50S BY TUESDAY. A WINTER STORM IS LIKELY WEDNESDAY INTO
THURSDAY...BUT THE DETAILS OF HOW MUCH RAIN OR SNOW WILL FALL IS
UNCERTAIN. COLD AND DRY WEATHER FOLLOWS...BUT A WARM UP IS
POSSIBLE FRIDAY AND SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
400 AM UPDATE...
LIGHT ECHOES ON THE RADAR ARE NOT HITTING THE GROUND AT THIS TIME
THANKS TO THE LARGE TEMP/DEWPOINT SPREAD. GUIDANCE SHOWS THAT THE
THE BETTER MOISTURE WONT ARRIVE UNTIL CLOSER TO 09 TO 12Z ALSO
COINCIDES WITH THE BETTER LIFT. LOOKING AT SURFACE OBS BELIEVE
THIS TREND IS POSSIBLE AS WARM FRONT CONTINUES TO MOVE
NORTHWARD...DEWPOINTS ARE STARTING TO INCREASE NOTING THAT THE
COLUMN IS STARTING TO SATURATE. TEMPERATURES CONTINUE TO HOLD
STEADY AND IN FACT STARTING TO INCREASE A DEGREE OR TWO. HAVE
ADJUSTED THE FORECAST ACCORDINGLY...WHICH WE COULD SEE A FEW
FLURRIES/LIGHT SNOW SHOWERS FALLING DURING THE MORNING COMMUTE.

TODAY...
WAA WILL INCREASE TODAY AS WARM FRONT CONTINUES TO LIFT
NORTHWARDS. DEPARTING SHORTWAVE WILL PUSH ANY LIGHT SNOW
SHOWERS/FLURRIES OFFSHORE BY THE MID-MORNING HOURS. ANY SNOW
ACCUMULATIONS WILL BE LIGHT OR NIL AS QPF IS LESS THAN AN
HUNDREDTH.

WEAK RIDGING WILL OCCUR BEHIND THE DEPARTING SHORTWAVE YET GUIDANCE
SHOWS SOME LOW LEVEL MOISTURE STICKY ROUND. THIS SEEMS REASONABLE THANKS
TO THE RETURN FLOW. 850MB TEMPS WILL WARM FROM -8C TO -2C AND
ALTHOUGH MIXING WILL NOT REACH THAT HIGH...A SURE SIGN THAT WARM
AIR ADVECTION IS OCCURRING. MIXING WILL BE SHALLOW TODAY AND WITH
ON AND OFF BREAKS IN THE CLOUDS IN THE AFTERNOON...BELIEVE TEMPS
WILL WARM AT OR NEAR AVERAGE. JUST A PRECURSOR FOR TOMORROW.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
ANOTHER UPPER LEVEL DISTURBANCE WILL RIPPLE THROUGH THE FLOW AND
MOVE INTO SOUTHERN NEW ENGLAND. THERE IS SOME WEAK LIFT AND
MOISTURE AS THE SHORTWAVE MOVES THROUGH...SO ANTICIPATE SOME
ISOLATED SHOWERS. GUIDANCE SHOWS THE BETTER LIFT AND MOISTURE WILL
RESIDE IN NORTHERN NEW ENGLAND WITH NORTHERN MA AND SOUTHERN NH
HAVING THE BEST SHOT FOR ANY PRECIPITATION. P-TYPE COULD BE AN
ISSUE...AT 925MB A WARM NOSE IS NOTICED ON SOME OF THE GUIDANCE
AND IF SURFACE TEMPS ARE COLD ENOUGH THEN PERHAPS SOME FREEZING
DRIZZLE IS POSSIBLE. YET AS WE GET CLOSER TO 12Z...SURFACE TEMPS
SHOULD WARM ABOVE FREEZING RESULTING IN LIQUID PRECIP.

OVERNIGHT TEMPERATURES WILL REMAIN AT OR JUST ABOVE FREEZING SOUTH
OF THE PIKE WHERE THE WARM AIR WILL MOVE INTO THE REGION FIRST.
NORTH OF THE PIKE WILL SEE TEMPS AT OR JUST BELOW FREEZING. OVERALL
RADIATIONAL COOLING IS NOT ANTICIPATED AS CLOUD COVER WILL
INHIBIT IT.

TUESDAY...
UPPER LEVEL SHORT MOVING ACROSS NORTHERN NEW ENGLAND WILL EXIT
OFFSHORE ALLOWING FOR RETURN FLOW TO THE REGION. 850MB TEMPS WARM
FROM 0C TO 4C...COMBINED WITH DEPARTING CLOUDS AND MARCH SUNSHINE
WE COULD SEE HIGH TEMPS WARM INTO THE LOW TO MID 50S. NAM
SOUNDINGS SHOW THE BEST MIXING WHICH COULD YIELD TO WARMER
TEMPERATURES. LIKE PREV FORECASTER LEANED TOWARDS THE ECMWF 2 M
TEMPS WHICH ARE THE WARMEST AND SEEM THE MOST REASONABLE AS ALL
OTHER GUIDANCE SEEMS TO COOL. AS MIXING OCCURS...THE WESTERLY
DOWNSLOPING WINDS WILL ALLOW FOR GUSTS TO INCREASE NEAR 20MPH AND
DEWPOINTS DROP INTO THE 20S. THIS COULD TURN INTO A POTENTIAL FIRE
WEATHER DAY...ALL DEPENDS ON HOW DEEP THE MIXING GETS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE... PACIFIC SHORTWAVE MOVES ASHORE THIS MORNING. BY
TUESDAY NIGHT IT WILL BE OVER THE CENTRAL PLAINS PHASING WITH A
SHORTWAVE MOVING AROUND THE ARCTIC LOW. MEANWHILE...A SOUTHERN
STREAM SHORTWAVE MOVES ALONG THE GULF COAST. THE TWO NORTHERN WAVES
PHASE TUESDAY NIGHT...DIGGING A TROUGH OVER THE EASTERN USA THAT
DRAWS THE GULF SHORTWAVE MOISTURE UP THE COAST. THE TROUGH SWEEPS
ACROSS NEW ENGLAND THURSDAY.  THE ARCTIC LOW MOVES SOUTH TO JAMES
BAY LATE IN THE WEEK GENERATING A BROADER CYCLONIC FLOW OVER THE
GREAT LAKES/NORTHEAST WHILE AN UPPER RIDGE BUILDS ALONG THE WEST
COAST.  THE BELOW NORMAL HEIGHTS SUGGEST A CORE OF COLD AIR EITHER
IN THE NEIGHBORHOOD OR OVERHEAD DURING THE WEEKEND.

MODEL PREFERENCES... WITH THE NORTHERN PACIFIC SHORTWAVE STILL FEET-
WET OVERNIGHT...AND THUS LESS-WELL SAMPLED...IT IS STILL TOO SOON TO
CONVERGE ON A DEFINITE SOLUTION. WE CONTINUE TO PREFER A BLEND OF
MODEL DATA.

THE DAILIES...

TUESDAY NIGHT... WEAK HIGH PRESSURE OVER THE REGION SHOULD KEEP
WEATHER DRY MOST OF THE NIGHT. INCREASING MOISTURE AT ALL LEVELS
OVERNIGHT POINTS TO INCREASING CLOUDS.  THE CLOUDS/A LACK OF COLD
AIR DRAINAGE/A MILD PRECEDING DAY SHOULD KEEP OVERNIGHT TEMPS NEAR
FREEZING. THERE IS SOME CONCERN THAT THE INCREASING CLOUDS MAY BRING
SLOWLY WARMING TEMPS OVERNIGHT WHICH IS NOT SHOWN IN THE MODEL DATA.

WEDNESDAY-THURSDAY... LOW PRESSURE IN THE PLAINS MOVES UP THE FRONT.
OPERATIONAL MODEL DATA POINTS TO A PASSAGE ALONG OR JUST SOUTH OF
THE COAST. ISENTROPIC LIFT FIELDS CONTINUE TO SHOW FAVORABLE
CONDITIONS MOVING INTO CT AND THE BERKSHIRES AROUND 12Z WEDNESDAY
AND THEN MOVING EAST ACROSS THE REGION MID MORNING. THIS TIMING OF
ONSET IS SIMILAR TO PREVIOUS PACKAGES.  MID LEVEL FRONTOGENESIS
LINES UP ACROSS THE EASTERN GREAT LAKES/CENTRAL NY/NCENTRAL PA AT
12Z...THEN MOVE ACROSS NEW ENGLAND BY MIDDAY.  THE MOST FAVORABLE
VALUES LINE UP ACROSS VT/NH/MAINE DURING WEDNESDAY...THEN MOVE EAST
WEDNESDAY NIGHT.

AS THE PARENT SYSTEM WAS STILL OVER THE PACIFIC AT THE TIME OF
INITIAL CONDITIONS...INSUFFICIENT CONFIDENCE TO MOVE TO CATEGORICAL
POPS. INSTEAD WE HAVE HELD AT HIGH-END LIKELY...68 TO 74 PERCENT.
THE PARENT SYSTEM MOVES ASHORE THIS MORNING...AND SO ONE WOULD
EXPECT CONFIDENCE TO INCREASE DURING THE DAY.

ASIDE FROM PCPN...QUESTION REMAINS AS TO PCPN TYPE.
CLIMATOLOGICALLY...THE NEARSHORE TRACK WOULD SUGGEST RAIN SOUTH OF
THE MASS PIKE AND SNOW OR A MIX TO THE NORTH. THERMAL FIELDS FROM
THE ECMWF AND GFS SHOW RAIN TO THE NH BORDER WEDNESDAY AFTERNOON. AS
THE SURFACE LOW PASSES WEDNESDAY NIGHT THE COLDER AIR BANKED OVER
THE ST LAWRENCE VALLEY GETS DRAWN SOUTH AND CHANGES THE THERMAL
FIELDS TO SNOW-FAVORABLE. SEVERAL HOURS OF SNOW ARE THEN POSSIBLE
WEDNESDAY NIGHT AND THURSDAY MORNING AS THE TRAILING PORTION OF THE
FRONTOGENESIS MAX SWEEPS SOUTHERN NEW ENGLAND...WITH SEVERAL INCHES
OF ACCUMULATION POSSIBLE.

THIS ANALYSIS IS OF COURSE BASED ON THE 00Z MODELS...AND AS NOTED
EARLIER THIS COULD CHANGE AS THE PARENT SYSTEM MOVES INTO THE NORTH
AMERICAN WX BALLOON DOMAIN. A HEADLINE MAY EVENTUALLY BE NEEDED WHEN
FORECAST CONFIDENCE INCREASES.

THURSDAY NIGHT-FRIDAY-SATURDAY-SUNDAY... STRONG GUSTY WINDS TRAILING
THE STORM WILL DRAW COLDER AIR ACROSS NEW ENGLAND. THIS WILL MEAN
ANOTHER CHILLY NIGHT...MODEL TEMPS IN THE SINGLE NUMBERS AND
EXPECTED WINDS WILL MEAN WIND CHILLS IN THE SINGLE NUMBERS BELOW
ZERO.  A WEAK RIDGE BUILDS ALOFT AND PUSHES THE COLDEST AIR
OUT...ALLOWING A TREND TO MORE SEASONABLE TEMPS FRIDAY AND SATURDAY.
CLIPPER LOW MOVES ACROSS CANADA SATURDAY AND SWINGS A COLD FRONT
ACROSS NEW ENGLAND. BEST SUPPORT IS IN THE NORTH...LESS SOUTH.  SO
LOW-END CHANCE POPS IN SOUTHERN NH AND SLIGHT CHANCE FARTHER SOUTH.
DRY WEATHER RETURNS FOR SUNDAY.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.

BEFORE 12Z...VFR CURRENTLY YET EXPECT MVFR CIGS TO DEVELOP ACROSS
NORTHERN MA AND SOUTHERN NH TOWARD 09Z ALONG WITH SCATTERED
SNOW/RAIN SHOWERS. ELSEWHERE VFR AND DRY.

TODAY...AREAS MVFR CIGS IN SCATTERED SNOW SHOWERS 09Z-15Z. SNOW
ACCUMULATIONS FROM A DUSTING TO PERHAPS AN INCH. IMPROVEMENT TO
VFR LATE MORNING AND AFTERNOON.

TONIGHT...MARGINAL MVFR-VFR IN ANOTHER ROUND OF SNOW
SHOWERS....FOCUS ON NORTHEAST MA AND SOUTHERN NH.

TUESDAY...VFR AND DRY ALONG WITH A MODEST NW WIND.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERTE CONFIDENCE.

TUESDAY NIGHT... VFR WITH INCREASING SKY COVER. POTENTIAL MVFR IN
LIGHT SNOW LATE AT NIGHT ESPECIALLY IN THE CT VALLEY AND BERKSHIRE
EAST SLOPES.

WEDNESDAY-THURSDAY... WELL DEVELOPED LOW PRESSURE PASSES JUST SOUTH
OF NEW ENGLAND. THIS WILL LIKELY BRING PCPN TO ALL AREAS. THERMAL
PROFILES SUGGEST MAINLY RAIN WEDNESDAY EXCEPT SNOW OR A RAIN/SNOW
MIX IN SOUTHERN NH.  ANY RAIN WILL CHANGE TO SNOW WEDNESDAY NIGHT AS
COLDER AIR GETS DRAWN SOUTH...WITH IFR/LIFR CONTINUING. EXPECT IFR
OR LIFR CIGS/VSBYS IN RAIN AND SNOW. WINDS AT 2000-3000 FEET WILL
REACH 50-60 KNOTS WEDNESDAY NIGHT CREATING CONCERN FOR LOW-LEVEL
WIND SHEAR.  CONDITIONS SLOWLY IMPROVE THURSDAY WITH SURFACE WINDS
SHIFTING TO NORTHWEST AND GUSTING TO 30 KNOTS.

FRIDAY... HIGH PRESSURE BUILDS FRIDAY WITH VFR CONDITIONS. A CLIPPER
MOVES ACROSS FROM THE GREAT LAKES FRIDAY NIGHT AND SATURDAY...AND
MAY BRING MVFR CIGS/VSBY IN RAIN OR SNOW SHOWERS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

HIGH CONFIDENCE THROUGH TONIGHT...MODERATE CONFIDENCE ON SEAS FOR
TUESDAY.

TODAY...SNOW SHOWERS POSSIBLE LIMITING VSBY TO 5 MILES...THEN
GOOD VSBYS BY THE AFTERNOON. LIGHT SW WINDS WITH A FEW GUSTS TO
15KTS.

TONIGHT... MODEST SW WIND WITH POSSIBLY SNOW SHOWERS ACROSS THE
NORTHERN WATERS. VSBYS COULD DROP TO 5 MILES.

TUESDAY...
FRONT MOVES OFFSHORE WITH A MODEST WNW WIND OVERSPREADING THE
WATERS. SEAS COULD BUILD TO 5FT ACROSS THE SOUTHERN OUTER WATERS.
LOW CONFIDENCE ON IF THIS WILL OCCUR TO HELD OFF ON SCA. GOOD
VSBY AND DRY WEATHER.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

TUESDAY NIGHT...WINDS AND SEAS BELOW SMALL CRAFT THRESHOLDS.

WEDNESDAY-THURSDAY...LOW PRESSURE MOVES THROUGH THE MID ATLANTIC
STATES AND APPROACHES THE COAST WEDNESDAY EVENING. WINDS AND SEAS
WILL INCREASE...REACHING SMALL CRAFT LEVELS LATE AFTERNOON/EVENING
AND POTENTIALLY REACHING NORTH-NORTHEAST GALES LATER WEDNESDAY NIGHT
AND THURSDAY. SEAS MAY REACH 10-16 FEET ON THE EASTERN WATERS AND 7
TO 10 FEET ON THE EXPOSED SOUTHERN WATERS.  A GALE WARNING MAY BE
NEEDED. WINDS BECOME NORTHWEST AT 30 KNOTS

FRIDAY...WINDS AND SEAS SLOWLY DIMINISH AS HIGH PRESSURE BUILDS
OVERHEAD.

&&

.TIDES/COASTAL FLOODING...
-- Changed Discussion --
HIGH TIDE WEDNESDAY NIGHT AT BOSTON IS 8.6 FEET.  HIGH TIDE FRIDAY
MORNING IS 9.4 FEET. A SURGE OF 2.5 TO 3 FEET MIGHT CAUSE MINOR
FLOODING ALONG THE MASS EAST COAST.  SEAS OF 10-16 FEET BEING PUSHED
TOWARD SHORE COULD RESULT IN SPLASHOVER/MINOR EROSION DURING THE
PERIOD. THIS WILL BE MONITORED.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...WTB/DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...