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Area forecast discussion 
National Weather Service Taunton Massachusetts
225 am EDT Friday Oct 9 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 this morning/...

2 am update...

No major changes with this forecast update. Showers just entering
western New York state at 2 am and will enter western Massachusetts around or
shortly after 12z. Thus dry weather prevails across the remainder
of the region. The combination of increasing clouds and southerly
winds will continue to result in rising temperatures early this morning.


Short term /6 am this morning through 6 PM Saturday/...

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 night 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 /06z Friday through Tuesday/...
forecaster confidence levels...

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

Through 12z...mainly VFR with low probability of a few showers entering
western Massachusetts toward 12z. Otherwise dry runways prevail.

After 12z...VFR then lowering to MVFR this afternoon as showers
move across CT/Rhode Island and Massachusetts from west to east. Few heavy embedded
showers along with an isolated T-storm possible. Strong low level
SW jet up to 45 knots moves across the area 18z-00z. Most of this
wind mixes to the surface.

Tonight...MVFR improves to VFR as cold front sweeps across the
area. Showers with embedded heavy downpours along with an isolated
T-storm moves offshore 00z-03z along with gusty SW winds shifting
to northwest.

Saturday...VFR with gusty north winds in the am diminishing in the

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

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

Outlook /Saturday night through Tuesday/...

Saturday night 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 night 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 this morning to 10 PM EDT this
evening for anz232>234-236.
Small Craft Advisory from 8 am this morning to 6 PM EDT this
evening for anz230.
Small Craft Advisory from 8 am this morning to 6 am EDT
Saturday for anz235-237-250-254>256.
Small Craft Advisory from 8 am this morning to 8 PM EDT this
evening for anz251.


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

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