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Area forecast discussion 
National Weather Service Taunton Massachusetts
426 PM EST Friday Nov 28 2014

dry but colder weather overspreads the region this afternoon
through Saturday. A warm front crosses the area Saturday night
with a light wintry mix of precipitation possible. Behind the
front much milder weather is on tap for Sunday and Monday. A polar
front will then sweep across the region later Monday...bringing a
return to colder weather Tuesday. A warm front may then bring another
risk of wintry precipitation toward the middle of next week.


Near term /through tonight/...
1 PM update...other than a few lingering rain showers on the
cape...precipitation has moved offshore as the inverted trough has pulled
away from southern New England. A Few Lake effect snow showers may
make it over the Berkshires from New York state later this
afternoon...but other than that...expect dry weather for the
remainder of today.

Partly to mostly cloudy skies will continue for most areas with
clouds pulling away from the East Coast but more moving in from
the northwest. Only ones seeing full sunny skies now is the south
coasts of Connecticut and Rhode Island.

Temperatures are in the low to middle 30s at most this afternoon and
expect thats as warm as we are going to get today given the low
sun angle and the cloudy skies.


Short term /Saturday/...
any leftover precipitation on the Outer Cape will exit the coast by
02z...then skies will become mostly clear. West-northwest winds will remain
a bit gusty early tonight along the coast...but winds across the
region will diminish as high pressure ridge builds east. Core of coldest
850 mb temperatures remains across northern New England...but will drop to
-10c to -13c overnight. With light winds...partly cloudy skies and
a new snowpack across S New Hampshire/north central and west Massachusetts...will see temperatures
fall to the single digits to lower teens there...while middle to
upper teens will be seen across most other areas overnight.
Readings will hold in the 20s along the immediate coast.


Long term /Saturday night through Friday/...
updated 340 am


* much milder Sunday and Monday
* return to chilly weather Tuesday
* seasonable temperatures toward the end of next week

Synoptic overview and model guidance evaluation...

Decent large scale agreement among the 28/12z guidance suite.
Relatively zonal flow aloft into the middle of next week calls
the timing of various features into question. The USA models
maintain a flatter middle level flow longer than the international
guidance. This is likely due to the handling of a potent shortwave
projected to arrive from the northwest Pacific. Since this is a
day 6/day 7 problem...will favor the consensus blend until the
energy of this shortwave can be better sampled.

Daily sensible weather details...

Saturday night...warm front approaches the region. Thus increasing
clouds with the chance of some spotty light precipitation. Model
soundings suggest any light precipitation would begin as light snow or
flurries then transitioning to sleet...and perhaps some freezing
rain...before completing the transition to all rain. Column
struggles to saturate so any precipitation should be light and
spotty. Hence not a high impact event.

Sunday and Monday...subtropical ridge briefly builds across the
southeast states and this pushes milder air northward into New
England with highs into the 50s across Rhode Island and eastern Massachusetts both
days. A polar cold front may yield the risk for a few rain showers
/possible ending as snow showers/ late Monday/Monday night.

Tuesday...1042 mb high and its associated polar airmass settle over
New England...with temperatures nearly 20 degrees colder than Monday.

Wednesday...overrunning precipitation possible with a wintry mix given cold
air will initially be slow to dislodge.

Thursday and Friday...trend is for drier but a return to colder...


Aviation /20z Friday through Wednesday/...
forecaster confidence levels...

Low...less than 30 percent.
Moderate...30 to 60 percent.
High...greater than 60 percent.

Short term /through Saturday/...high confidence.

Through 00z...conditions should improve gradually to VFR from
west to east through the afternoon.

Tonight...any locations along the East Coast that have lingering
MVFR conditions will improve quickly to VFR.


Kbos terminal...high confidence.

Kbdl terminal...high confidence.

Outlook...Saturday night through Wednesday...moderate confidence.

Saturday night-Sunday...lowering clouds Saturday night with
potential for MVFR ceilings/visibilities in widely scattered precipitation late at
night and Sunday morning. Low level winds...around 2000 feet...
will increase overnight and Sunday to 40-45 knots and may create
low level wind shear.

Monday...VFR with scattered showers late or at night as a cold front
moves through. Southwest winds ahead of the cold front will switch
to northwest after this front moves through.

Tuesday...VFR with north to northeast winds.

Wednesday...scattered MVFR with mainly southeast winds.


forecaster confidence levels...

Low...less than 30 percent.
Moderate...30 to 60 percent.
High...greater than 60 percent.

Short term /through tonight/...high confidence.

Today...N-NW winds will increase during the morning with gusts up
to 25 knots mainly across eastern areas. Seas will also build again
up to 5-6 feet mainly over the open waters. Winds will briefly gust
to 25 feet across Cape Cod Bay and Nantucket Sound around midday so
have put up small craft there. Winds will begin to diminish late
in the day.

Tonight...W-NW winds will diminish early tonight but seas will
remain at or above 5 feet on the outer waters after midnight before finally

Outlook...Saturday through Wednesday...moderate confidence.

Saturday night...small risk of a few showers of rain or snow as a
high pressure moves farther offshore.

Sunday...warm front lifts north through the region. Modest SW
wind develops...but mainly dry weather.

Monday...cold front remains west of New modest SW
winds continue.

Tuesday...cold high pressure drifts across southern Quebec and
northern New England. Lighter northeast winds with gradually
diminishing seas.

Wednesday...high pressure moves farther northeast into the
Maritimes. Winds shift from south to southwest during the day.
Relatively light seas.


Box watches/warnings/advisories...
New Hampshire...none.
Rhode Island...none.
Marine...Small Craft Advisory until 4 PM EST this afternoon for anz231-
Small Craft Advisory until 10 PM EST this evening for anz250-
Small Craft Advisory until 3 am EST Saturday for anz254-255.


near term...rlg
short term...rlg
long term...Belk

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