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Area forecast discussion 
National Weather Service Taunton Massachusetts
424 PM EDT Monday Sep 1 2014

Synopsis...
warm...humid airmass remains over southern New England through
Tuesday with showers and thunderstorms possible each afternoon. A
cold front moves across the region Tuesday night. Warm but less
humid weather will follow for Wednesday through Friday. Another
cold front may bring a chance of showers and thunderstorms
Saturday.

&&

Near term /until 6 am Tuesday morning/...
isolated to scattered showers and thunderstorms have popped up south
of the Mass Pike. With minimal shear in place...not expecting any
severe weather. While we have yet to see any cloud to ground
lightning with these storms...with 1500 j/kg of SBCAPE
available...thunder is definitely possible. Most likely threat
with these storms is heavy rainfall and urban flooding.

Tonight...any lingering showers and thunderstorms will diminish as
the sun GOES down and afternoon heating diminishes. Then another
night similar to last night with fog and stratus developing...particularly
along the South Coast...cape...and islands. Fog is also possible
in the CT River Valley. With the warm...humid airmass still in
place...expect low temperatures in the middle 60s to around 70.

&&

Short term /6 am Tuesday morning through Tuesday night/...
Tuesday...southwesterly flow continues to bring warm moist air into
southern New England. This will actually be the most summery
weather we have had in the last month. Expect high temperatures to get
into the upper 80s to near 90 ahead of a cold front approaching
southern New England.

All this heat and humidity will increase the chances for showers and
thunderstorms. Best dynamics remain to our north and west through
much of the day but approach our northwestern zones during the
afternoon. However...there is plenty of instability indicated by
the lifted indices...k indices...and cape. Again the most likely
threat with these storms will be heavy rain and urban flooding.

Tuesday night...the cold front will move across southern New England
bringing an end to the showers and thunderstorms and ushering in a
drier airmass. Fog and stratus are possible once again along the
South Coast...cape...and islands ahead of the front moving through.

&&

Long term /Wednesday through Monday/...
overview and model preferences...
01/12z models remain in good overall agreement with good
continuity. Main features this week will be a broad ridge across
the southern USA...with a nearly zonal flow along the USA/Canadian
border. Some timing and amplitude differences in the middle-level
flow arise toward this weekend...especially with the handling of a
middle-level low approaching southern New England from Hudson Bay.

Continued to use a blend of the available guidance to smooth over
some of the minor detail differences.

Daily details...

Wednesday...surface high pressure will build east out of the Great
Lakes...allowing drier air to spill in across the region during
the day as winds shift to northwest. However...with the general offshore
flow in place and 500 mb heights rising as a broad ridge build
aloft...looks like temperatures will remain unseasonably warm.

May see some patchy fog develop in normally prone valley areas
Wednesday night. Winds become light and variable...which will help
to promote fog development.

Thursday and Friday...high pressure will dominate...so expecting
dry and warm conditions to continue across our region. Dew points
will be comfortable...mainly in the middle 50s to around 60...on
Thursday. But look to start rising back into the 60s on Friday as
a high pressure moves offshore and southwest winds take over.

Saturday and Sunday...model runs tending to diverge on the
breakdown of the upper level pattern across the eastern USA during
this timeframe and the approach of a cold front...so lower
forecast confidence with respect to timing. At this point...
thinking a cold front will approach during Saturday...then move
offshore Saturday night or early Sunday with a high pressure
returning.

Monday...high pressure should be in control of our weather once
more.

&&

Aviation /20z Monday through Saturday/...
forecaster confidence levels...

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

Short term /through Monday night/...high confidence in
trends...lower confidence in timing.

Through 00z...IFR ceilings linger along the South Coast with VFR
conditions elsewhere. Isolated to scattered rain showers/thunderstorms and rain across CT/RI/se mass
this afternoon/evening with locally heavy downpours possible.
Brief MVFR/IFR in any thunderstorms. Sea breeze along both coasts
resulting in southeasterly winds at Logan.

Tonight...evening rain showers/thunderstorms and rain especially over the cape and islands.
Brief MVFR/IFR in any storms. Quiet weather the remainder of the
night with areas of IFR in stratus and fog. Best chance will
again be along the South Coast and islands as well as the CT River
Valley.

Tuesday...morning fog and IFR conditions burn off. VFR through
much of the day. Increasing clouds from the west during the
afternoon/evening with potential for brief MVFR in scattered
thunderstorms.

Tuesday night...MVFR/IFR conditions in stratus and fog likely
again...particularly along the South Coast...cape...and islands.
Cold front moves through after midnight allowing rain showers/thunderstorms and rain to end
and conditions to improve.

Kbos terminal...high confidence in trends. Lower confidence on
timing. Seabreeze continues through sunset.

Kbdl terminal...high confidence in trends. Lower confidence on
timing.

Outlook...Wednesday through Saturday...

Moderate confidence. Expecting mainly VFR conditions. Local MVFR-
IFR visibilities and ceilings in late night patchy fog and low clouds. Main
areas of concern will be the typically prone locations across the
far interior /SW New Hampshire and north central and western MA/. On Thursday
night...with SW winds in place...may see patchy fog and stratus
along the South Coast with local MVFR-IFR conditions as well.

&&

Marine...
forecaster confidence levels...

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

High confidence. Mostly quiet boating weather. Fog and low stratus
is likely each night and may persist into the morning hours. There
is a very low chance of showers and thunderstorms moving over the
waters each afternoon/evening.

Outlook...Wednesday through Saturday...

Moderate confidence through this period.

Expecting winds and seas to remain below small craft criteria
through Friday. Winds become southwest again late Thursday
night into Friday...then increase Friday night into Saturday.
These increased winds should result in building seas...which may
approach 5 feet across the outer coastal waters Saturday.

&&

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

&&

$$
Synopsis...Belk/rlg
near term...rlg
short term...rlg
long term...Belk
aviation...Belk/rlg
marine...Belk/rlg

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