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Area forecast discussion 
National Weather Service Taunton Massachusetts
305 PM EDT Friday Aug 28 2015

Synopsis...

High pressure moving off the coast will keep our weather dry this
weekend but with a warming trend. Very warm to hot weather along
with humidity will return for much of next week...but a backdoor
front may bring briefly cooler temperatures on the coast Tuesday and
perhaps again by the end of the week.



&&

Near term /through tonight/...

Diurnal cumulus clouds will dissipate this evening with the loss of
daytime heating. Otherwise...high pressure overhead and a
relatively dry airmass in place for August standards will set the
stage for a relatively cool night. Low temperatures will bottom out
between 50 and 55 in the normally coolest outlying...to the upper
50s and lower 60s in most of the urban centers. Patchy ground will
likely develop late in the typically prone locations.

&&

Short term /Saturday through Saturday night/...

Saturday...

High pressure slides off the coast allowing temperatures to rise a
few degrees higher then today. High temperatures on Sat should top out
mainly in the 80 to 85 degree range with plenty of sunshine.
Dewpoints will generally remain below 60...so still quite
comfortable for the last weekend in August.

Saturday night...

Moisture starved shortwave will pass to our north and should result
in some middle level cloudiness. However...given lack of low level
moisture/forcing expect our weather to remain dry. Low temperatures should
not be quite as cool as tonight...but should still drop into the
middle to upper 50s in the normally cooler outlying locations while
urban centers should see lows mainly in the lower to middle 60s.
Expect more late night patchy ground fog in the typically prone
locations.

&&

Long term /Sunday through Thursday/...

Highlights...

* surface high pressure will linger over the weekend
* anomalous strong ridge builds during the work week
* low confidence on the potential for a back door front

Overview...

00z guidance is in good agreement for this portion of the forecast.
There are some uncertainty with regards to the strength of a few
passing shortwaves but this should not impact the overall trend in
the forecast. Upper level ridge will begin to build over the region.
Potent shortwave moving over the Maritimes may bring a back door
front by Tuesday. Middle-level ridge builds into the area by the second-
half of the week lasting into next weekend. Overall have high
confidence that temperatures will generally be above average through
the period...with very little appreciable rain.

Dailies...

Sunday into Tuesday...moderate confidence.

Offshore high pressure will allow for return flow to the region on
Sunday and Monday. This will increase moisture and temperature will
reach into the middle 80s on Sunday and Monday.

Ridge will then begin to build to the west of the region on Tuesday.
Guidance is showing a maritime shortwave passing through the
flow...increasing the risk for a backdoor cold front. This is a low
confidence as it is all dependent on where the ridge finally sets
up...but did lower the NE mass coast a few degrees on Tuesday.
Otherwise much of the region will be in the middle to upper 80s.

Wednesday into Friday...moderate confidence.

Summer returns as the heat and humidity really increases. High
pressure will strengthen during this period with the 500mb heights
higher than normal. Temperatures at the 850 millibar level will be
well above normal reaching around 16-18c. Overall precipitation chances
will low during the period thanks to the dome of high pressure.
However because of the increasing moisture...cape values will
increase as well. Cannot rule out the potential for hit or miss
diurnal convection each day. Because of the uncertainty in the
timing and location will continue with a dry forecast.

&&

Aviation /18z Friday 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/...

Tonight through Saturday night...high confidence. VFR conditions
except in brief localized patchy ground fog in the typically prone
locations very late tonight and again very late Saturday night.

Kbos terminal...high confidence in taf. Sea breezes come to an end
between 00z and 02z this evening. A few hours of sea breezes may
occur on Saturday...but confidence on them developing is not as high
as they were today and they should not last as long.

Kbdl terminal...high confidence in taf.

Outlook /Sunday through Tuesday/...high confidence.

Sunday into Tuesday...VFR conditions. Sea breezes along the coast
possible.

&&

Marine...
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.

Weak pressure gradient will keep winds and seas below Small Craft
Advisory thresholds through Saturday night. Winds will generally
have a southerly trajectory from tonight into Saturday night as high
pressure slowly moves east of the waters.

Outlook /Sunday through Tuesday/...high confidence.

A period of quiet boating weather is expected thanks to building
high pressure. Winds out of the SW through the period with the potential
of 20 knots gust Sunday afternoon. Winds could switch to the
north/northeast on Tuesday...but low confidence.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...none.

&&

$$
Synopsis...Frank
near term...Frank
short term...Frank
long term...dunten - update coming soon
aviation...Frank/dunten
marine...Frank/dunten

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