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Area forecast discussion 
National Weather Service Taunton Massachusetts
955 am EDT Sat Oct 25 2014

Synopsis...
a weak ridge of high pressure moves across the region
today providing sunshine and mild weather. A cold front will sweep
across the area tonight and may be accompanied by a few showers.
Dry...cool and blustery weather follows Sunday into Monday...before
temperatures moderate Tuesday and especially by Wednesday. A cold
front may bring a brief period of scattered showers Wednesday
afternoon and evening followed by much cooler temperatures Thursday
into Friday.

&&

Near term /until 6 PM this evening/...
*** sunshine and mild temperatures return today ***

1000 am update...

Bulk of the forecast remains on track this morning. Weak shortwave
is moving across the region this morning per latest water vapor
imagery. A few stratus clouds and patchy fog are still lingering
across the interior...but should burn off from diurnal heating
within the next hours. Temperatures are on track to reach into the 60s
later this afternoon.

Previous discussion...
weak short wave ridging and associated subsidence moves across
the area today providing partly to mostly sunny skies along with
temperatures about 5 degrees warmer than normal. Model soundings
suggest blyr mixing extends up to about 925 mb. Temperatures at this
level are around +10c. This supports highs in the low to middle
60s...slightly cooler higher terrain. However it will feel even
milder given light winds today. West winds 5 to 15 miles per hour will
support warm readings along the coast including Cape Cod and the
islands. Temperatures may fall back a few degrees here later in the day as
winds back to the southwest off the ocean.

&&

Short term /6 PM this evening through 6 PM Sunday/...
tonight...

Impressive northern stream short wave plunging southeastward across
Lake Superior early this morning. Very strong jet dynamics with this
feature however best synoptic scale forcing and deep layer moisture
tracks across northern New York and northern New England tonight.
Therefore the cold front associated with this short wave will likely
only yield a few showers from 00z/8pm to 06z/2am across northern Massachusetts
and southwest New Hampshire. Otherwise the remainder of southern New England
should remain dry. Behind the frontal passage /06z/ west-northwest winds
increase in response to increasing cold air advection.

Sunday...

About 10 degrees or so colder than Sat along with a brisk northwest
wind behind the departing cold front. Potent trailing short wave
trough comes through the region in the afternoon. In response to modest
cold air advection 925mb-700mb lapse rates increase to 7c/km. This
combined with synoptic scale lift from the approaching short wave
should yield a few afternoon showers. Deep layer moisture is lacking
and this should limit areal coverage to isolated or widely
scattered. Cooler temperatures aloft will combine with cloud cover to yield
highs only in the 50s. In addition gusty northwest winds will make it feel
even cooler.

&&

Long term /Sunday night through Friday/...
highlights...

* dry and cool Monday
* remaining dry but milder on Tuesday
* unseasonably mild Wednesday with some 70 degree readings possible
* period of scattered showers possible Wednesday afternoon and/or evening
* turning much cooler by next Thursday and Friday

Details...

Sunday night...

West to northwest winds behind the cold front will continue to usher
cooler air into the region. Winds will not decouple and
it will remain gusty across portions of the coastal plain. Low
temperatures will fall between 40 and 45 in most locations by daybreak
Monday...but enough wind will keep low temperatures from really bottoming
out.

Monday...

Partly to mostly sunny skies and cool temperatures continue on Monday with
northwest flow aloft and at the surface. High temperatures should reach
into middle to upper 50s...but it will be breezy. BUFKIT soundings
continue to show good mixing that will support northwest wind gusts
of 20 to 30 miles per hour.

Monday night...

A ridge of high pressure builds in from the west resulting in
decoupling winds and a good night of radiational cooling. Low temperatures
will fall well down into the 30s across the outlying locations...to
the lower to middle 40s in the urban centers.

Tuesday...

The high pressure system moves off the coast early Tuesday allowing a
return southwest flow of air to work into the region. We should see
at least partial sunshine. This should result in high temperatures to
reach into the lower to middle 60s...but it should remain dry.

Wednesday...

Southwest flow ahead a cold front will allow for an unseasonably mild
day. Guidance numbers are likely too cool based on pattern
recognition and support from European model (ecmwf)/ggem 2 meter temperatures. 850
mb temperatures near 10c and good mixing should support highs in the upper
60s to lower 70s across most of the region. The cold front will
probably trigger a brief band of scattered showers Wednesday afternoon
and/or evening. Moisture will be limited...so expect any rain to be
of a short duration in a given location with light amounts.

Thursday and Friday...

High pressure will build into the region behind the front bringing
mainly dry weather Thursday into much of Friday but with much cooler
temperatures. High temperatures should generally be in the 50s on both
days. A secondary front will probably move through the region late
Friday...bringing the coldest weather so far this season to start
the next weekend. Will have to watch if a wave of low pressure
forms along the front late Friday or Friday night...but confidence is low.

&&

Aviation /14z Saturday through Wednesday/...
forecaster confidence levels...

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

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

7 am update...

Today...VFR.

Tonight...VFR to start but then quickly a brief period of marginal
MVFR/VFR ceilings move across the area associated with a cold front.
Low risk of a few showers across northern Massachusetts into southwest New Hampshire
00z-06z. May see a few gusts up to 20 knots toward daybreak.

Sunday...cold front moves offshore in the morning but lots of Post
frontal clouds in the bkn035-045 category. Low risk of a few light
showers in the afternoon. West winds will gusts 20-25 knots in the
afternoon.

Kbos...high confidence in taf through 00z...then slightly lower
confidence on timing of MVFR/VFR ceilings.

Kbdl...high confidence in taf through 00z...then slightly lower
confidence on timing of MVFR/VFR ceilings.

Outlook...Sunday night through Wednesday

High confidence. Mainly VFR other than a brief period of MVFR
conditions Wednesday afternoon/evening in a band of scattered rain showers.

&&

Marine...
forecaster confidence levels...

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

Short term /through Sunday/...

Forecast confidence is high through Sunday.

Today...

Modest northwest winds this morning become westerly around midday and then
SW toward sunset. Dry weather and good visibility today. NE swells
continue to subside across the eastern Massachusetts waters.

Tonight...

Cold front sweeps across the waters 03z-06z with west-northwest winds
increasing to 20-30 knots. A few light rain showers possible northern
Massachusetts waters.

Sunday...

West-northwest winds remain strong at 20-30kt. Low risk of a few light rain
showers in the afternoon. Otherwise good visibility.

Outlook...Sunday night through Wednesday...

Sunday night and Monday...high confidence. West to northwest winds
behind a cold front will gust to between 25 and 30 knots in the cool
air advection pattern. There is even a low probability of brief
near 35 knot wind gusts across the eastern outer-waters.
Regardless...Small Craft Advisory headlines will be needed for all waters Sun night
into Monday.

Monday night and Tuesday...moderate to high confidence. Winds/seas
diminish below Small Craft Advisory thresholds as high pressure builds in from the
west.

Tuesday night and Wednesday...moderate confidence. High pressure
moves off the coast allowing for a return of southwest winds across
the waters. Marginal southwest Small Craft Advisory wind gusts may develop by Wednesday
afternoon across the southern waters.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
New Hampshire...none.
Rhode Island...none.
Marine...Small Craft Advisory from 5 PM this afternoon to 6 am EDT
Monday for anz232>235-237-254>256.
Small Craft Advisory from midnight tonight to 6 am EDT Monday
for anz230-231-236-250-251.

&&

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

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