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Area forecast discussion 
National Weather Service Taunton Massachusetts
956 PM EDT Sat Oct 25 2014

Synopsis...
a cold front will sweep across the area tonight and may be
accompanied by a few showers. Cool and blustery weather will
follow Sunday with the chance of a brief afternoon shower. Dry
weather prevails early in the week with a warming trend by
Wednesday. A cold front may bring a few showers late Wednesday.
Cooler air follows behind the front for later in the week. A low
pressure system may bring wet weather Friday night into Saturday
morning...before colder air arrives for next weekend.

&&

Near term /until 6 am Sunday morning/...

10 PM update...

Area of showers associated with lead short wave and surface trough
is fairly disorganized with a few broken lines of showers over
western and northern New England into eastern New York. Latest runs of
hrrr and rap13 has trended weaker with shower activity. This seems
reasonable as best forcing for ascent and deeper moisture tracks
across northern New England. Thus expect areal coverage to be
isolated to widely scattered. Therefore will lower probability of precipitation to chance
category to reflect this thinking. Hence...by no means a
washout...just the risk of a brief light rain shower as acitivity
is falling from a middle deck of clouds. Will have to watch new area
of convection that has developed over Lake Ontario. Hrrr and rap13
bring that activity in a weaken state into southern New England
during the predawn hours. Earlier discussion below.

-------------------------------------------------------------------

Behind front...decent cold advection gets underway on increasing
west/northwest winds. Lows in 40s to near 50 look good.

&&

Short term /6 am Sunday morning through Sunday night/...
tomorrow and tomorrow night...

Upper level trough will remain over ahead for Sunday and Sunday
night. See a secondary shortwave moving through the flow which may
trigger a few diurnally driven showers on Sunday. Biggest question
is the amount of moisture...but soundings show there is just enough.
Aside from a few showers...anticipate mostly cloudy skies which will
limit diurnal heating. Temperatures on Sunday will struggle to reach
60 in many locations. Sunday will also see strong gusty westerly
winds of 20-30 miles per hour due to steep lapse rates and the strong cold air advection still
aloft. Went a few miles per hour higher then guidance at it seems that models
are underdoing the gust potential within the pattern. Appears that
the GFS BUFKIT soundings are on track...especially on what is occurring
right now.

Winds will slowly die down overnight but still remain a tad gusty.
Clouds will begin to clear as upper level ridge begins to move
towards the northeast. Temperatures may drop to the low 40s as gusty winds
will limit radiational cooling.

&&

Long term /Monday through Saturday/...
highlights...

* dry Monday/Tuesday with warming trend
* mild Wednesday with few afternoon/evening showers
* a lot of uncertainty by end of week but turning colder next weekend

Details...

Monday and Tuesday...

Ridging builds over northeast in advance of upper low lifting across
upper Great Lakes. High pressure initially over Middle Atlantic States
will maintain dry but brisk west/northwest flow Monday which diminishes and
becomes more S/SW Tuesday as high shifts offshore. Highs stay in 50s Monday
but should reach low-middle 60s Tuesday with at least partial sunshine
based upon model 2m temperatures.

Wednesday...

Approaching cold front will bring unseasonably mild SW flow to
region. Despite fact 12z models bring front into western New England
during morning and move it offshore Wednesday evening....moisture is
limited and dynamics are rather weak across southern New England.
Therefore only expecting some cloudiness and perhaps a few showers.
This should still allow highs to reach 60s if not 70 across parts of
eastern Massachusetts since cool air lags well behind front.

Thursday...

High pressure builds from Ohio Valley to middle Atlantic coast. Drier northwest
flow prevails with highs mainly in 50s.

Friday and Sat...

Uncertainty increases dramatically as models struggle with
development of broad eastern US trough/closed low from combination
of Pacific energy and upper low east of Hudson Bay. 12z European model (ecmwf) is much
farther S across Carolinas and deeper with its upper low by next
weekend...as compared to 12z GFS which takes upper low across
northern New England. This has implications on how everything plays
out Friday into Sat with European model (ecmwf) painting a much wetter scenario than GFS
which shows more progressive system exiting New England Sat. For now
we will use blend of models to Iron out differences which gives
chance probability of precipitation Friday night into Sat...but we may need to extend mention
of precipitation into Sat should European model (ecmwf) solution become more likely. Does
look like shot of colder air arrives next weekend either way.

&&

Aviation /02z Sunday through Thursday/...
forecaster confidence levels...

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

10 PM update...

No major changes from 00z tafs.

-------------------------------------------------------------

Short term /through Sunday night/...high confidence.

Tonight...VFR. Band of showers will move across southern New
England 00z-06z and may bring brief MVFR cigs/vsbys...mainly
across north Massachusetts and SW New Hampshire. May see a few gusts up to 25 kts toward
daybreak near coast.

Tomorrow...cold front moves offshore in the morning but lots of
Post frontal clouds in the bkn040 category. Low risk of a few
light showers in the afternoon. West winds will gusts 20-30 knots in
the afternoon.

Tomorrow night...VFR. A few gusts up to 20 kts possible.

Kbos...high confidence in taf. May see brief MVFR ceilings/visibilities in
showers 03z-06z sun but more likely conditions stay VFR.

Kbdl...high confidence in taf.

Outlook...Monday through Thursday...high confidence.

Monday and Tuesday...VFR.

Wednesday...MVFR possible in scattered showers.

Thursday...VFR.

&&

Marine...
forecaster confidence levels...

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

Short term /through Sunday night/... high confidence.

10 PM update...

Winds beginning to increase along the south coastal waters.
Previous forecast a bit too quick with the onset of these stronger
winds. Otherwise forecast is on track. Earlier discussion below.

------------------------------------------------------------------

Tonight...
cold front sweeps across the waters 06z-12z with west-northwest winds
increasing to 20-30 knots. Southern waters will see occasional west-northwest
gales...so have hoisted a Gale Warning. A few light rain showers
possible northern Massachusetts waters.

Sunday...

West-northwest winds remain strong at 20-30kt. Anticipate west-northwest gales across
the southern waters by the afternoon hours. Have extended the Gale
Warning to account for these gusts. Low risk of a few light rain
showers in the afternoon. Otherwise good visibility.

Sunday night...

West-northwest gales will slowly subside but gusts of 30 kts will continue
through the overnight in the cold air advection pattern. Otherwise
good visibilities and dry weather.

Outlook...Monday through Thursday...high confidence.

Monday...high pressure over middle Atlantic will keep west/northwest winds near Small Craft Advisory early
before winds diminish during afternoon. Seas near 5 feet on outer
waters will gradually subside as well.

Tuesday...high pressure moves off middle Atlantic coast resulting S/SW flow
across waters but winds and seas will remain below Small Craft Advisory.

Wednesday...increasing SW flow ahead of cold front approaching from
Great Lakes. Winds and seas may reach Small Craft Advisory...mainly on open S coastal
waters...before front brings wind shift to northwest during evening.
Nothing more than few showers expected with front.

Thursday...high pressure builds from Ohio Valley to middle Atlantic coast...
bringing diminishing northwest winds and seas.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
New Hampshire...none.
Rhode Island...none.
Marine...Gale Warning until 2 am EDT Monday for anz232>235-237-254>256.
Small Craft Advisory until 9 am EDT Monday for anz230-231-236-
250-251.

&&

$$
Synopsis...dunten/jwd
near term...nocera/dunten/jwd
short term...dunten
long term...jwd
aviation...nocera/dunten/jwd
marine...nocera/dunten/jwd

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