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Area forecast discussion 
National Weather Service Taunton Massachusetts
955 am EDT Sat Aug 29 2015

Synopsis...
high pressure moving off the coast will bring dry conditions with
a warming trend this weekend. Very warm to hot weather will
return for much of next week with Wednesday and Thursday possibly
being the hottest days of the week. A weak backdoor front may
bring briefly cooler temperatures on the coast Tuesday.

&&

Near term /until 6 PM this evening/...
10 am update...

Patchy ground fog has been slow to burn off this morning. Expect
it to continue to lift as the sun heats up. Mostly sunny to sunny
skies expected through the rest of the day. Made a few minor
tweaks to the temperatures but otherwise...the forecast is on
track.

Previous discussion...

High pressure moves off the coast with slight warming at 850 mb
resulting in temperatures a few degrees warmer than Friday with readings
mostly 80-85 degrees except upper 70s along the S coast and higher
terrain. A few diurnal cumulus will develop but mosunny skies expected.
Comfortable humidity levels with dewpoints in the 50s.

&&

Short term /6 PM this evening through 6 PM Sunday/...
tonight...
weak shortwave passes well to the north which will bring some middle
level clouds...especially north areas. Otherwise a dry night with low
temperatures a bit milder than the last few nights with readings middle to
upper 50s in the cooler locations and low to middle 60s urban centers
and coastal areas. Patchy fog possible in the typically prone
locations.

Sunday...
weak surface trough develops across southern New England and guidance is indicating
increasing moisture in the column as higher Theta-E air moves in
along with increasing ki values. This will result in a few more
clouds although still expect ptsunny skies. There is no
instability so expect mainly dry weather but cant rule out a
brief shower within low level Theta-E ridge axis. 850 mb temperatures
around 15c support maxes into the middle 80s...cooler S coast and
higher terrain. Dewpoints remain mostly in the 50s in the
interior...but increasing into the 60s in the coastal plain where
it will becoming a bit more humid.

&&

Long term /Sunday night through Friday/...
highlights...

* anomalously strong ridge builds during the work week
* there is potential for a back door front Tuesday
* heat wave possible for western zones Monday-Thursday

Overview...

00z guidance is in good agreement for this portion of the forecast.
There is 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. Upper-level ridge strengthens into the
area by the middle to latter half of the week lasting into next
weekend. Still some uncertainty on where the axis of the ridge
will build. But overall have high confidence that temperatures
will generally be above average through the period...with very
little appreciable rain.

Dailies...

Monday into Tuesday...moderate confidence.

High pressure moves offshore as northwest flow aloft dominates on
Monday. Westerly flow at the surface will allow for dewpoints to
mix out and winds to increase to near 20 miles per hour. 850 mb temperatures will
increase reaching around 16c. This will yield temperatures in the
upper 80s with the potential for a few locations reaching 90f.

Potent shortwave will move through the Maritimes on Tuesday bringing
the potential for a backdoor cold front to the region. The GFS is
more pronounced while the ec keeps it close to the immediate
coast. Because of the uncertainty used a blend of guidance which
keeps coastal communities cooler on Tuesday but western zones
still reaching upper 80s near 90f.

Wednesday into Friday...moderate confidence.

Summer returns as high pressure strengthens during this period.
Wednesday and Thursday look to be the warmest of the week as the
axis of the ridge builds over the region. 850mb temperatures will be well
above normal reaching around 17-19c. Which will lead to high temperatures
in the u80s to l90s. This could potentially lead to the CT River
Valley seeing a 3 to 4 day heat wave. Overall precipitation chances will
be 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. Thursday seems to the best day for a
chance of precipitation as upper level heights fall slightly. However
because of the uncertainty in the timing and location will
continue with a dry forecast.

&&

Aviation /14z Saturday through Wednesday/...
forecaster confidence levels...

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

Short term /through Sunday/...

Today through Sunday...high confidence. VFR. Localized IFR fog
developing again late tonight in the typically prone locations.

Kbos terminal...high confidence in taf. A few hours of a weak
seabreeze may develop by early afternoon...but not very
confident.

Kbdl terminal...high confidence in taf.

Outlook /Sunday night through Wednesday/...high confidence.

VFR conditions through the period. 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 Sunday/...high confidence.

Quiet boating weather as weak pressure gradient will keep winds
and seas below Small Craft Advisory thresholds through Sunday.
Expect S/SW winds through the period.

Outlook /Sunday night through Wednesday/...high confidence.

Winds and seas remain below small craft criteria. Expect light SW
winds through Monday...then may briefly shift to NE-east Tuesday before
veering back to S-SW again Wednesday. Low chance for near shore waters
seeing gusts around 20 kts on Monday.

&&

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

&&

$$
Synopsis...kjc/dunten
near term...kjc/dunten/rlg
short term...kjc
long term...dunten
aviation...kjc/dunten
marine...kjc/dunten

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