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Area forecast discussion 
National Weather Service Taunton Massachusetts
1011 PM EDT Thursday Oct 8 2015

low pressure and its attending cold front will yield widespread
showers to the region Friday afternoon and evening. High pressure
follows for this Holiday weekend...bringing dry weather along
with a warming trend. A cold front may bring a few showers Tuesday
before dry weather returns Wednesday and Thursday.


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

10 PM update...

Only change with this forecast update was to adjust temperatures downward
across southeastern Massachusetts as temperatures remain in freefall given dry
airmass... clear skies and light winds. Many locations in
southeast Massachusetts are already down into the low to middle 40s! However
this will be short lived as return flow strengthens with near
shore buoys already reporting southeast winds 10-15 knots. This expecting
temperatures to stabilize and then begin to rise late or toward morning.

Latest radar trends along with 18z NAM/GFS/21z sref and latest
runs of the rap and hrrr hold off most of the showers until after
12z. The exception will be northwest Massachusetts that may see some showers
toward 12z. Otherwise most of the region remains dry overnight.
Earlier discussion below.


Mostly clear skies this evening will give way to increasing clouds
later tonight. Temperatures will drop off quickly now that sun has
set before recovering due to clouds and S flow overnight. Made
minor adjustments to temperatures which reflect this trend.

Leading edge of showers in advance of cold front still well back
across Great Lakes. Kept in chance of showers across northwest Massachusetts after
midnight...but do not expect much in way of rain prior to daybreak
which agrees with 21z hrrr.


Short term /6 am Friday morning through Friday night/...
Friday...southern New England will be dealing with the
combination of a robust middle level shortwave and a cold front. The
parent low pressure of this storm will most probably remain to our
north...which would place our region in a more favorable region
for thunderstorms. Instability is rather poor...but there may be
enough shear from the low level jet to organize the energy which
will be in place. Kept a mention of isolated thunderstorms in the

The other issue which remains is the potential for gusty winds.
Latest bufr soundings from both the GFS and NAM continue to
indicate gust potential just under Wind Advisory criterion. The
greatest risk would be across the coastal plains of Rhode Island and
southeast Massachusetts. Thinking there might be too strong a marine
inversion over the cape and islands. Not confident enough to issue
a Wind Advisory at this time. That said...even these winds speeds
may be sufficient to bring down small branches and limbs given
trees remain fully-leaved.

Seasonable temperatures expected...which will be a bit of a warmup
from today...despite the clouds.

Friday night...any showers will come to an end as a cold front
moves through and away from southern New England. Expecting gusty
northwest winds with this front...particularly across southeastern
Massachusetts and Rhode Island...where the low level jet moves
across and has the potential to mix down stronger winds.


Long term /Saturday through Thursday/...
* dry with a warming trend for the Holiday weekend
* few showers Tuesday followed by dry and seasonable weather

Medium range models and ensembles point to relatively quiet stretch
of weather into next week despite series of upper troughs moving
through...leading to overall high confidence in forecast.

One Point of uncertainty deals with upper low ejecting from
southeastern states Monday/Tuesday which should weaken as it runs into
ridging over Atlantic. Question of whether it gets shunted well out
to sea having little effect on southern New England...or does it
become captured by trough entering Great Lakes which allows moisture
to be drawn into approaching cold front.

Sat through Monday...

Holiday weekend looking great for outdoor activities as high
pressure builds into region. What is initially a chilly start Sat
with highs in 50s warms into 60s if not some lower 70s by Monday as
high moves offshore and SW flow develops.


Approaching cold front brings chance of showers to much of region.
Probably not looking at much in way of rainfall unless moisture from
ejecting southern stream closed low can get into picture...which
will need to be worked out over next couple of days. As of now gefs
keeps bulk of that rainfall offshore.

Wednesday and Thursday...

Dry and seasonable weather returns as high pressure once again
builds over New England.


Aviation /02z Friday through Tuesday/...
forecaster confidence levels...

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

10 PM major changes from 00z tafs. Showers hold off
until after 12z Friday. Earlier discussion below.


High confidence through Friday night.

Sea breezes subside this evening with light S/SW flow prevailing
tonight. Pushed back timing of MVFR ceilings until well after midnight
in western New England as satellite shows VFR ceilings all way back
to eastern Great Lakes which will take some time to arrive. Any
showers should hold off until Friday morning.

Friday...MVFR becomes more widespread as showers become more
numerous from west to east. Low level wind shear possible after
18z as strong low level SW jet develops over southeast Massachusetts. Small
risk for isolated thunderstorms.

Friday night...mainly VFR. Brief MVFR/IFR conditions in any
lingering -shra/fog during the evening. Gusty northwest winds behind a
cold front.

Kbos terminal...high confidence in taf.

Kbdl terminal...high confidence in taf.

Outlook /Saturday through Tuesday/...

Saturday through Monday...VFR. High confidence.

Tuesday...MVFR possible in scattered showers. High confidence.


forecaster confidence levels...

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

Tonight...quiet weather with high pressure moving farther
offshore. Winds will become south-southwest toward morning.

Friday...south-southwest winds increase as low pressure moves into northern New
England. South-southwest winds 20 to 30 knots with a few gusts up to 40 knots
possible. We may need a Gale Warning for some of the coastal
waters...but have higher confidence in Small Craft Advisory winds
at this time.

Friday night...a cold front will cross the waters...increasing
winds and seas. In addition...showers are likely with this
front...limiting visibilities. Small craft advisories continue for
most waters.

Outlook /Saturday through Tuesday/...

High pressure builds over waters Sat with diminishing winds and
seas...but may need to continue small craft advisories for 5 feet seas
on outer waters. High moves offshore sun/Monday resulting in S/SW flow
but winds and seas expected to stay below Small Craft Advisory.

Cold front approaches Tuesday with few showers possible. Expect
increasing SW winds ahead of front but probably remaining below Small Craft Advisory.
Seas may build to 5 feet on outer waters...more as result of possible
swells from low pressure to our S than from cold front itself.


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory from 8 am to 10 PM EDT Friday for
Small Craft Advisory from 8 am to 6 PM EDT Friday for anz230.
Small Craft Advisory from 8 am Friday to 6 am EDT Saturday for
Small Craft Advisory from 8 am to 8 PM EDT Friday for anz251.


near term...nocera/jwd
short term...Belk
long term...jwd

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