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Area forecast discussion 
National Weather Service Taunton Massachusetts
338 PM EDT Friday Oct 9 2015

low pressure and its attending cold front will yield widespread
showers to the region this afternoon and evening. Behind this
front...drier and much cooler weather late tonight into Saturday.
High pressure provides dry weather for the remainder of this
Holiday weekend along with a warming trend Sunday and Monday. A
cold front may bring a few showers Monday night into Tuesday...
before dry weather returns Wednesday and Thursday.


Near term /until 6 am Saturday morning/...
*** heavy showers & gusty winds likely this afternoon and evening ***

325 PM update...

Lowered maximum temperatures earlier clouds have
largely taken over.

Excellent agreement among the 09/12z guidance suite regarding the
timing of a cold front across southern New England this afternoon
and evening. Expecting this front to reach the coast of northeast
Massachusetts toward 8 PM...and the Cape Cod canal toward 11 PM. This front
should be offshore by 2 am...and well offshore toward daybreak
Saturday. Expecting a band of widespread rain/showers ahead of
this front as it passes by.

Latest mesoanalysis showed very little energy to work with across
southern England. Effective bulk shear was an impressive 40 knots.
Monitoring some lightning over PA...but that is in an environment
with greater cape to tap into. Thinking thunderstorms will be less
of a concern across most of Massachusetts and Rhode Island later today. CT has the
highest risk due to less of a marine influence...and its proximity
to an area of greater cape to our south.

Gusty winds remain a concern. Many reports of small limbs falling
already today. Even without thunderstorms...strong showers may be
enough to drag higher wind speeds to the ground. Thus far...based
on reports and observed wind speeds...thinking southern New
England will remain below Wind Advisory criteria. Wind
Advisory at this time.

Once the front passes by...we dry out quickly late this evening
and overnight. Seasonable low temperatures tonight.


Short term /6 am Saturday morning through Saturday night/...
definitely a fall-like period...with temperatures near...or
slightly below...normal. High pressure in control for this portion
of the forecast. Gusty winds diminish quickly Saturday morning.

Clear skies and relatively light wind Saturday night set the stage
for the possibility of frost headlines...and perhaps some
localized freeze conditions as well. Right now...thinking this
will be mainly across the northern tier of Massachusetts into the CT River
Valley. This will need to be monitored over the next 36 hours.


Long term /Sunday through Friday/...
* more seasonable temperatures expected through the long term
* dry weather and a warming trend for Sunday and Monday
* another chance of rain Tuesday with a cold front

Models are in good agreement through the long term on the overall
synoptic scale pattern. Dry weather returns for the Holiday weekend
before a cold front moves through the region Tuesday. Then high
pressure returns with dry weather for Wednesday and Thursday.
Another cold front moves through southern New England Friday with a
potential for showers. Temperatures will generally be seasonable
through the period with some variations ahead of and behind the two

Sunday through Monday...dry weather is expected during this time
with a warming trend as winds shift to the southwest.

Monday night and Tuesday...a northern stream shortwave moves through
southern New England Tuesday as low pressure moves through Quebec
into the Maritimes. This will bring a cold front through southern
New England. About the same time low pressure from the Carolinas
moves northward...phasing with the northern stream system. The
combination of those two systems should result in showers both in
the west with the front and in the east with the southern stream
system. In addition...there is some marginal instability along the
South Coast so there may be some isolated thunder as well.
Temperatures are expected to be several degrees above normal.

Wednesday and Thursday...high pressure builds into southern New
England with somewhat cooler temperatures but dry weather returning
to the region. There is a low probability of precipitation occurring on
Thursday with a pre-frontal trough. Only the GFS enhances this
trough with a strong middle level shortwave. In addition...any showers
would have a great deal of dry air to will keep probability of precipitation
to slight chance in this time period.

Friday...looks like another cold front moves through southern New
England...bringing another round of showers to the region.


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

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

Through 00z...mainly VFR...with MVFR in showers. Gusty southwest winds
continue...with the possibility for low level wind shear.

Tonight...high confidence. Moderate confidence in specific timing
for individual terminals. MVFR improves to VFR behind a cold
front. Showers with embedded heavy downpours along with an
isolated T-storm moves offshore 00z- 03z along with gusty SW winds
shifting to northwest.

Saturday...high confidence. VFR with gusty north winds in the
morning...diminishing in the afternoon.

Saturday night...high confidence VFR.

Kbos terminal...high confidence in taf trends...but lower on exact

Kbdl terminal...high confidence in taf trends...but lower on
exact details.

Outlook /Sunday through Wednesday/...

Sunday through Monday...high confidence. VFR.

Monday night and Tuesday...moderate confidence. A cold front moves
across the region with MVFR/IFR conditions possible in any -shra
that occurs ahead of the front. Expect gusty westerly winds with the
frontal passage.

Wednesday...high confidence. VFR.


forecaster confidence levels...

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

Tonight...south-southwest winds 20 to 30 knots shifting to northwest this evening with
the passage of a cold front. Heavy showers early move offshore
later this evening. Very low risk of an isolated thunderstorm
early across the southernmost coastal waters.

Saturday...high confidence. Gusty north winds early diminish by
midday as a high pressure builds over the waters. Seas subside as
well. Dry weather and good visibility.

Saturday night...high confidence relatively tranquil boating

Outlook /Sunday through Wednesday/...

Moderate confidence. Looks like a quiet boating period with winds
and seas below small craft criteria for the most part. A front
crosses the waters Tuesday and may result in gusty winds...
however...confidence is low as to how high the gusts may get.


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory until 10 am EDT Saturday for anz231>235-
Small Craft Advisory until 8 am EDT Saturday for anz230-236-
Small Craft Advisory until 2 PM EDT Saturday for anz250.
Small Craft Advisory until 4 PM EDT Saturday for anz254-255.
Small Craft Advisory until noon EDT Saturday for anz256.


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

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