Wednesday, February 28, 2007

NWS going with 4 to 8 in Keene

Special Weather Statment:

Special Weather Statement


SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
307 AM EST WED FEB 28 2007

CTZ002>004-MAZ002>019-026-NHZ011-012-015-RIZ001>005-282100-
HARTFORD CT-TOLLAND CT-WINDHAM CT-WESTERN FRANKLIN MA-
EASTERN FRANKLIN MA-NORTHERN WORCESTER MA-CENTRAL MIDDLESEX MA-
WESTERN ESSEX MA-EASTERN ESSEX MA-WESTERN HAMPSHIRE MA-
WESTERN HAMPDEN MA-EASTERN HAMPSHIRE MA-EASTERN HAMPDEN MA-
SOUTHERN WORCESTER MA-WESTERN NORFOLK MA-SOUTHEAST MIDDLESEX MA-
SUFFOLK MA-EASTERN NORFOLK MA-NORTHERN BRISTOL MA-
WESTERN PLYMOUTH MA-EASTERN PLYMOUTH MA-NORTHERN MIDDLESEX MA-
CHESHIRE NH-EASTERN HILLSBOROUGH NH-
WESTERN AND CENTRAL HILLSBOROUGH NH-NORTHWEST PROVIDENCE RI-
SOUTHEAST PROVIDENCE RI-WESTERN KENT RI-EASTERN KENT RI-
BRISTOL RI-
INCLUDING THE CITIES OF...HARTFORD...WINDSOR LOCKS...UNION...
VERNON...PUTNAM...WILLIMANTIC...CHARLEMONT...GREENFIELD...
ORANGE...BARRE...FITCHBURG...FRAMINGHAM...LOWELL...LAWRENCE...
GLOUCESTER...CHESTERFIELD...BLANDFORD...AMHERST...NORTHAMPTON...
SPRINGFIELD...MILFORD...WORCESTER...FOXBORO...NORWOOD...
CAMBRIDGE...BOSTON...QUINCY...TAUNTON...BROCKTON...PLYMOUTH...
AYER...JAFFREY...KEENE...MANCHESTER...NASHUA...PETERBOROUGH...
WEARE...FOSTER...SMITHFIELD...PROVIDENCE...WEST GREENWICH...
WARWICK...BRISTOL
307 AM EST WED FEB 28 2007

...A STORM SYSTEM WILL BRING A MESSY MIXTURE OF WINTRY PRECIPITATION
LATE THURSDAY NIGHT AND FRIDAY...

SNOW IS EXPECTED TO DEVELOP LATE THURSDAY NIGHT ACROSS WESTERN
MASSACHUSETTS AND CONNECTICUT...REACHING THE COASTAL PLAIN TOWARD
DAYBREAK ON FRIDAY.

WARMER AIR MOVING IN AT THE MID LEVELS OF THE ATMOSPHERE WILL QUICKLY
CHANGE THE SNOW TO SLEET IN THE PROVIDENCE TO TAUNTON CORRIDOR EARLY
FRIDAY MORNING...BEFORE A CHANGE TO ALL RAIN BY LATE MORNING. TOTAL
SNOW AND SLEET ACCUMULATIONS LOOK TO RANGE FROM BETWEEN ONE HALF AND
2 INCHES. ACROSS FAR SOUTHWESTERN MASSACHUSETTS...NORTHERN
CONNECTICUT AND NORTHWEST RHODE ISLAND...SNOW AND SLEET ACCUMULATIONS
ARE ALSO EXPECTED TO RANGE FROM BETWEEN ONE HALF AND 2 INCHES.
HOWEVER...THIS AREA MAY SEE THE SLEET CHANGE TO A PERIOD OF FREEZING
RAIN BEFORE CHANGING TO ALL RAIN BY LATE MORNING. IF THIS
OCCURS...UNTREATED ROADWAYS MAY BECOME VERY ICY. THE BEST CHANCE FOR
THIS WILL BE IN THE CONNECTICUT RIVER VALLEY.

FURTHER NORTH...THE BOSTON METROPOLITAN AREA CAN EXPECT 1 TO 3
INCHES OF SNOW BEFORE A CHANGE TO SLEET BY MID TO LATE MORNING. THE
SLEET WILL CHANGE TO A WINDSWEPT RAIN BY EARLY AFTERNOON AS
TEMPERATURES RISE TO NEAR 40. UNLIKE THE VALENTINES DAY STORM...TEMPERATURES
ARE EXPECTED TO REMAIN ABOVE FREEZING ALONG THE COASTAL PLAIN FOR
MUCH OF FRIDAY EVENING. THIS SHOULD PREVENT THE FLASH FREEZE THAT
OCCURRED WITH THE LAST STORM.

AREAS TO THE NORTH OF THE MASSACHUSETTS TURNPIKE CAN EXPECT 3 TO 6
INCHES OF SNOW...WITH THE HIGHER AMOUNTS NEAR THE NEW HAMPSHIRE
BORDER. THE PRECIPITATION SHOULD CHANGE TO SLEET BY LATE MORNING OR
EARLY AFTERNOON. THERE ALSO MAY BE A PERIOD OF FREEZING
RAIN...PARTICULARLY IN THE WORCESTER HILLS BEFORE THE PRECIPITATION
CHANGES TO ALL RAIN BY MID AFTERNOON.

THE HEAVIEST SNOW ACCUMULATIONS ARE EXPECTED ACROSS SOUTHERN NEW
HAMPSHIRE. TOTAL SNOW ACCUMULATIONS SHOULD RANGE BETWEEN 4 AND 8
INCHES. THE SNOW IS EXPECTED TO CHANGE TO SLEET FRIDAY
AFTERNOON...AND MAY END AS SOME DRIZZLE OR FREEZING DRIZZLE BY
LATE IN THE AFTERNOON.

THERE IS STILL SOME UNCERTAINTY IN THE TRACK OF THIS SYSTEM. IF THE
STORM TRACKS FURTHER SOUTH...SNOW AMOUNTS WILL BE A BIT HIGHER. IF
THE STORM TRACKS FURTHER NORTH...SNOW AMOUNTS WILL BE LESS. THE WINTRY
PRECIPITATION IS EXPECTED TO IMPACT THE FRIDAY MORNING RUSH
HOUR...ESPECIALLY NORTHWEST OF I-95 SO MOTORISTS SHOULD BE PREPARED.

$$

FRANK



Taunton NWS Area Forecast Discussion:
000
FXUS61 KBOX 281200
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
700 AM EST WED FEB 28 2007

.MORNING UPDATE...
WE SENT OUT A QUICK ZFP UPDATE TO CLEAR THINGS OUT A LITTLE FASTER
BASED ON LATEST SATELLITE TRENDS. FLURRIES NOW CONFINED TO
CAPE/ISLANDS AND WILL BE EXITING REGION BY MID TO LATE MORNING
FOLLOWED BY INCREASING SUNSHINE.

&&

.AVIATION /12Z-12Z/...
SCT FLURRIES AND LOCAL MVFR CIGS CONFINED TO CAPE/ISLANDS AT 12Z AND
EXPECT IMPROVING CONDITIONS THRU THE MORNING WITH CLOUDS SCATTERING
OUT BY MIDDAY. PATCHY FOG IN THE INTERIOR VALLEYS WILL BURN OFF
SHORTLY. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH
SCT CU TODAY AND SKC TNGT.

&&

.PREV DISCUSSION...
/ISSUED 337 AM EST WED FEB 28 2007/

..A STORM SYSTEM WILL BRING A MESSY MIXTURE OF WINTRY PRECIPITATION
LATE THURSDAY NIGHT AND FRIDAY...

SHORT TERM /TODAY THROUGH THURSDAY/...
KBOX RADAR SHOWING AN AREA OF FLURRIES MOVG ACRS NE CT...RI AND SE
MA ASSOCD WITH WEAK MID LEVEL SHORTWAVE S OF THE COAST. THE
FLURRIES LINE UP WELL WITH 850-700 MB MSTR AS DEPICTED BY GFS WHICH
HANGS ON TO THIS MSTR ACRS SE ZONES THRU 12Z BEFORE DRYING MOVES IN
BY 18Z. WE WILL MENTION CHC MORNING FLURRIES FOR RI/SE MA THIS
MORNING...OTRW WE EXPECT INCREASING SUNSHINE MOVING IN FROM WEST TO
EAST LATER THIS MORNING INTO THE AFTERNOON. WEAK COLD FRONT WILL
SLIDE S OF REGION THIS AFTN BUT CROSS SECTIONS ARE DRY SO NO PRECIP
EXPECTED WITH THIS FNT. 2M TEMPS SUGGEST MAXES REACHING UPPER 30S
TO LOWER 40S.

HIGH PRES ACRS SE CANADA WITH RIDGE EXTENDING SWD ACRS LAKES WILL
MOVE EWD INTO SNE LATE TNGT INTO THU BRINGING A COLDER AND DRIER
AIRMASS WITH NORTHERLY DRAINAGE WIND. EXPECT MOCLR SKIES TNGT WITH
MINS RANGING FROM NEAR 10 FAR NW TO 20-25 NEAR THE COAST.

THIS HIGH WILL SLOW ONSET OF MSTR APPROACHING FROM WEST DURING THU
ENSURING A DRY DAY...BUT CLOUDS WILL BE INCREASING FROM SW TO NE
DURING THE AFTERNOON. DESPITE WARMER MID LEVEL TEMPS ON
THU...SHALLOW COOL AIR WILL RESULT IN COOLER TEMPS WITH MAXES
GENERALLY 35-40.

LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE MAIN CONCERN WITH THIS FORECAST IS HOW MUCH SNOW WILL FALL
ACROSS OUR COUNTY WARNING AREA BEFORE A CHANGE TO SLEET AND RAIN.

A LOW PRESSURE SYSTEM EAST OF THE ROCKY MOUNTAINS WILL RAPIDLY
INTENSIFY AS IT MOVES INTO THE CENTRAL PLAINS TONIGHT AND THURSDAY.
THIS SYSTEM WILL OCCLUDE AND SPAWN A SECONDARY LOW PRESSURE SYSTEM
OVER THE MID ATLANTIC STATES THURSDAY EVENING. THIS WILL BECOME THE
PRIMARY PLAYER FOR OUR MESSY WEATHER LATE THURSDAY NIGHT AND FRIDAY.
MODELS ARE CONVERGING ON AN INLAND TRACK TO THIS LOW PRESSURE
SYSTEM...SOMEWHERE NEAR THE I-95 CORRIDOR. THERE ARE A FEW GFS
ENSEMBLES THAT PAINT A COLDER SOLUTION AND MORE SNOW TO AREAS NORTH
OF THE MA PIKE THAN WE ARE ADVERTISING WITH THIS FORECAST. `
HOWEVER...BASED ON THE REASONING BELOW WE WILL LEAN TOWARDS THE
WARMER SOLUTIONS WHICH ARE ALSO SUPPORTED BY MODEL CONSENSUS.

SNOW SHOULD OVER SPREAD THE INTERIOR LATE THURSDAY NIGHT AND REACH
THE COASTAL PLAIN TOWARD MORNING. THE NAM MODEL SEEMS A BIT FAST
WHEN COMPARING TO THE OTHER MODELS. A STRONG LOW LEVEL JET WILL
ALLOW MID LEVEL TEMPERATURES TO RAPIDLY WARM. WE USUALLY PREFER TO
TAKE THE MORE CONSERVATIVE APPROACH IN FORECASTING SNOW AMOUNTS
UNDER STRONG WARM ADVECTION. THE REASONING FOR THAT IS BECAUSE IT
ONLY TAKES A VERY SMALL LAYER OF THE MID LEVELS TO WARM AND CHANGE
THE PRECIPITATION QUICKLY OVER TO SLEET. IN ADDITION...WE TEND TO
DRY SLOT IN THE MID LEVELS OF THE ATMOSPHERE UNDER THESE
SITUATIONS. THIS RESULTS IN THE SNOW GROWTH RAPIDLY FALLING BELOW
IDEAL LEVELS. THIS LOOKS TO HAPPEN BY EARLY AFTERNOON WHICH SHOULD
BRING AN END TO THE SUBSTANTIAL PRECIPITATION.

THE ONE THING WE ARE GOING TO HAVE TO WATCH IS IF THE SLEET
TRANSITIONS OVER TO FREEZING RAIN ACROSS PORTIONS OF THE INTERIOR
FOR A TIME. IT LOOKS LIKE TEMPERATURES EVEN IN THE INTERIOR SHOULD
COME UP TO AROUND FREEZING BY LATE MORNING AS UNLIKE THE VALENTINES
DAY STORM WE DO NOT HAVE MUCH SHALLOW COLD AIR. WITH THE EARLY
MARCH SUN ANGLE THIS SHOULD PREVENT A MAJOR ICE STORM...BUT WE CAN
NOT LET OUR GUARD DOWN YET.

WITH ALL THAT SAID...BASED ON MODEL CONSENSUS AND PATTERN
RECOGNITION HERE IS OUR BEST ESTIMATE AND SNOWFALL TOTALS. IN THE
HARTFORD...TO PROVIDENCE TO TAUNTON AREA GENERALLY EXPECTING JUST A
HALF TO 2 INCHES OF SNOW AND SLEET BEFORE A TRANSITION TO RAIN. NOW
WE ARE GOING TO HAVE TO WATCH THE CONNECTICUT RIVER VALLEY FOR A FEW
HOURS OF FREEZING RAIN AS THE COLD AIR IS TRAPPED THERE FOR A TIME.
HOWEVER...EXPECT TEMPERATURES TO COME UP TO AROUND FREEZING BY MID
TO LATE MORNING AND THIS TIME OF YEAR THAT SHOULD PREVENT A MAJOR
FREEZING RAIN EVENT. IN FACT...TEMPERATURES ACROSS MUCH OF THE
CONNECTICUT VALLEY SHOULD INCH ABOVE FREEZING DURING THE AFTERNOON.

FOR BOSTON...WE EXPECT 1 TO 3 INCHES OF SNOW WHICH WILL CHANGE TO
SLEET IN THE EARLY TO MID MORNING HOURS OF FRIDAY. THE
PRECIPITATION WILL CHANGE TO ALL RAIN BY NOON AS TEMPERATURES RISE
WELL UP INTO THE 30S TO NEAR 40.

ACROSS NORTHERN MA...WE EXPECT 3 TO 6 INCHES OF SNOW BEFORE WE
CHANGE OVER TO SLEET BY LATE MORNING WITH THE HIGHER AMOUNTS NEAR
THE NEW HAMPSHIRE BORDER. SLEET MAY TRANSITION TO A PERIOD OF
FREEZING RAIN. MOST AREAS WILL PROBABLY SEE THE MERCURY INCH ABOVE
FREEZING IN THE EARLY AFTERNOON ALLOWING THE PRECIPITATION TO CHANGE
TO ALL RAIN. THE WORCESTER HILLS MAY SEE THE MERCURY HANG AROUND
FREEZING...BUT HIGH EARLY MARCH SUN ANGLE SHOULD PREVENT MAJOR
PROBLEMS WITH FREEZING RAIN BASED ON OUR TEMPERATURE FORECAST.

THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS SOUTHERN NEW HAMPSHIRE
WHERE WE WILL FORECAST 4 TO 8 INCHES OF SNOW BEFORE A TRANSITION TO
SLEET. EVEN HERE THE PRECIPITATION SHOULD END AS SLEET OR FREEZING
RAIN IN THE AFTERNOON AS THE DRY SLOT MOVES INTO THE REGION BY LATE
AFTERNOON.

ALTHOUGH WE ARE FORECASTING MARGINAL WATCH/WARNING CRITERIA FOR
SOUTHERN NH...THIS IS EXPECTED TO BE A 4TH AND 5TH PERIOD EVENT. WE
LIKE TO ONLY ISSUE WATCHES FOR 4TH PERIOD EVENTS WHEN CONFIDENCE IS
VERY HIGH. THEREFORE...WILL LET THE DAY SHIFT ASSESS THE 12Z MODEL
DATA BEFORE ISSUING ANY WATCHES.

UNLIKE THE VALENTINES STORM...SHALLOW COLD AIR IS NOT EXPECTED TO
RACE DOWN THE COASTAL PLAIN FRIDAY EVENING. THIS SHOULD PREVENT THE
FLASH FREEZE THAT OCCURRED WITH THE LAST SYSTEM.


OTHERWISE...PRECIPITATION COMES TO AN END EARLY FRIDAY EVENING.
ANOTHER DISTURBANCE MAY BRING A FEW RAIN SHOWERS TO THE REGION
SATURDAY AND SATURDAY EVENING SO WILL CARRY CHANCE POPS. THIS DOES
NOT LOOK TO BE A BIG DEAL. BOUNDARY LAYER TEMPERATURES SHOULD
RECOVER WELL UP INTO THE 40S TO POSSIBLY NEAR 50...SO NOT REALLY
CONCERNED ABOUT FROZEN PRECIPITATION.

SEASONABLE TEMPERATURES WITH GENERALLY DRY WEATHER ARE EXPECTED FOR
SUNDAY AND MONDAY. THE ECMWF/UKMET/CANADIAN HAVE A STRONG COLD
FRONT MOVING THROUGH THE REGION MONDAY NIGHT BRINGING WELL BELOW
NORMAL TEMPERATURES ON TUESDAY. THE GFS IS AN OUTLIER AND MUCH
WARMER SO STUCK WITH THE PREVIOUS FORECAST AND UNDERCUT MEX GUIDANCE
SIGNIFICANTLY. INCLUDED A 20 POP FOR A FEW FLURRIES/SNOW SHOWERS
WITH THE STRONG COLD FRONT.

AVIATION /08Z-06Z/...
WE HAVE MAINLY VFR CONDITIONS EARLY THIS MORNING. LOWEST CIGS THIS
MORNING WILL BE CONFINED TO KPVD/KHYA/KACK WHERE BRIEF MVFR AND
FLURRIES PSBL...WITH MID CLOUDS ELSEWHERE. CLOUDS EXPECTED TO
SCATTER OUT LATER THIS MORNING INTO THE AFTERNOON ACRS SNE. SKC
TNGT.

MARINE...
SHORT TERM...NO PROBLEMS ON THE WATERS ANTICIPATED THROUGH THU WITH
WINDS UNDER 15 KTS AND SEAS 3 FT OR LESS.

IN THE LONG TERM... ALTHOUGH AN INVERSION WILL BE IN
PLACE...GRADIENT SHOULD BE STRONG ENOUGH TO PRODUCE 35 TO 40 KNOT
WIND GUSTS OVER THE OPEN WATERS ON FRIDAY. UNDERCUT WNA MODEL A BIT
WITH THE INVERSION...BUT STILL EXPECT SEAS TO BUILD TO AROUND 10
FEET OVER OUR OUTER-WATERS WITH A GOOD FETCH.

FIRE WEATHER...
WE WILL BEGIN TO ISSUE FIRE WEATHER FORECASTS WITH THIS PACKAGE.
THE FIRE WEATHER FORECASTS WILL NOW BE AVAILABLE 12 MONTHS OUT OF
THE YEAR. THE PRODUCT WILL BE ISSUED ROUTINELY TWICE A DAY WITH THE
EARLY MORNING AND LATE AFTERNOON FORECAST PACKAGE. THE FORECAST
WILL ALSO BE UPDATED ANYTIME CONDITIONS WARRANT.

&&

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

$$

UPDATE...KJC

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