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Area forecast discussion 
National Weather Service Taunton Massachusetts
701 PM EDT Monday Aug 31 2015

a weak cold front will usher a brief reprieve in the hot and humid
weather for Tuesday. But short-lived as it returns for Wednesday
and Thursday. Another cold front should bring showers and thunderstorms
Thursday. Then slightly cooler weather Friday into the Holiday
weekend...but temperatures will still be above normal with mainly
dry weather continuing.


Near term /until 6 am Tuesday morning/...
7 PM update...made minor updates to the temperatures and sky grids
to account for the latest trends. Otherwise...the forecast is on


Middle-level impulse through the cyclonic flow shunts a cooler and
drier airmass southeast across New England. It is with the passage of a
weak cold front along the leading edge that we will see winds shift
west/northwest as dewpoints drop slightly. Scattered to broken cloud decks in
what will overall be a quiet and mild night. Lows down around the
middle- to upper-60s northwest to southeast as usual. Patchy fog in typically prone


Short term /6 am Tuesday morning through Tuesday night/...

Ridging building behind the overnight impulse yields an overall
light west-flow across the region. +14-16c 850 mb airmass lingers within
the light wind pattern resulting a brief reprieve of hot and humid
conditions. Looking at highs around the middle- to upper-80s with
dewpoints ranging around the low-60s. Sea-breezes likely along the
shores ahead of which moisture convergence and boundary-layer mixing
should yield scattered to broken pancake-like cumulus.

Tuesday night...

Ridging still in place pushing a warm-dry airmass across the region
aloft. 850 mb temperatures warming up around +20c. Appearing like a
good setup of moisture trapping at the surface...and combined with
high pressure and light winds allowing for a measure of radiational
cooling...could be talking about a greater potential for fog. Lows
around the low- to middle-60s with similar dewpoint values.


Long term /Wednesday through Monday/...

* unseasonably hot Wednesday and Thursday
* a bit cooler Friday into the Holiday weekend but still above normal
* mainly dry other than a few showers/storms Thursday

Models are in excellent agreement through the long term with a broad
upper level ridge approaching from the Great Lakes and holding
steady over the northeastern United States through the entire long
term period. Overall...high pressure dominates at the surface as
well. The only exception to this is a cold front extending from
low pressure in the Maritimes that will move southward through
southern New England late Wednesday night into Thursday morning.

Wednesday and Thursday...the two hottest days of the week with 850mb
temperatures in the upper teens leading to high temperatures in the
middle 80s to low 90s. Also...the most interesting period in the
long term forecast as a cold front works its way south through
southern New England bringing a chance of showers and thunderstorms
to the region Thursday. Moisture is not ideal but theres enough of
it to result in convective available potential energy in the 1000-2000 j/kg range. With no not expect any severe weather to occur but feel there
is enough moisture and instability for a few showers and
thunderstorms to occur.

Friday through Labor Day...temperatures will be a bit cooler thanks
to the cold front but still several degrees above normal for the
first week in September. Expect high temperatures in the lower
80s for most of southern New England. With high pressure in place
over the region...expect sea breezes will likely keep temperatures
down a few degrees along the coasts.


Aviation /00z Tuesday through Saturday/...
forecaster confidence levels...

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

Short term /through Tuesday night/...

00z update...

Today through Tuesday night...high confidence.

VFR. Patchy IFR fog in typically prone locations overnight. Light
west-winds with sea-breezes likely Tuesday. Patchy possibly
widespread IFR fog into Wednesday morning.

Kbos terminal...high confidence in taf. Sea breeze likely by
late-morning Tuesday.

Kbdl terminal...high confidence in taf.

Outlook /Wednesday through Saturday/...high confidence.

Mainly VFR conditions throughout the period. Low probability of
brief MVFR conditions with isolated rain showers/thunderstorms and rain Thursday. Also...IFR visibilities
possible in patchy fog each night.


forecaster confidence levels...

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

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

Subsequent wind stress and swell from SW winds gusting upwards of
20 kts earlier today may result in wave heights of 5 feet on the
S/southeast waters overnight. Overall think waves will remain below 5
feet. Cold front sweeps the waters late allowing winds to back
west/northwest while becoming light. This will allow for sea-breezes along
the immediate shores into Tuesday...dissipating Tuesday night.

Outlook /Wednesday through Saturday/...high confidence.

Near stationary upper ridge and surface high pressure will result
in light winds and fairly calm seas. Expect quiet boating weather
with winds and seas both below Small Craft Advisory criteria. Patchy fog may limit
visibilities at times.


Box watches/warnings/advisories...
Rhode Island...none.


near term...rlg/sipprell
short term...sipprell
long term...rlg

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