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Area forecast discussion 
National Weather Service Taunton Massachusetts
650 am EDT sun Aug 30 2015

a weak upper level disturbance will bring more clouds and possibly
a brief shower today...otherwise dry weather with a warming trend
through Monday. A backdoor cold front will bring slightly cooler
weather Tuesday...mainly near the coast...before hot weather
returns Wednesday and Thursday. Another backdoor cold front should
bring slightly cooler weather Friday and into the Holiday weekend.
Dry weather should prevail most of the week.


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

Forecast on track and only minor adjustments made.

Weak middle level shortwave will bring a fair amount of clouds today
as middle level moisture increases across the region. We expect
partial sunshine at times but also mostly cloudy periods. Models do show
increasing moisture in the column as precipitable waters increase to 1.5" and
ki values increase into the lower 30s but there is little to no
instability. While most of the day will be dry...cant rule out a
few brief showers developing within the low level Theta-E ridge
axis as moisture moves into southern New England but coverage of showers should be
limited. We have slight chance probability of precipitation. Followed a blend of all
available guidance which brings maximum temperatures into the middle 80s which
is in line with 850 mb temperatures around 15c. Cooler temperatures immediate
South Coast and higher terrain. Humidity levels will increase
slightly with dewpoints upper 50s to lower 60s.


Short term /6 PM this evening through 6 PM Monday/...
Theta-E ridge and ki axis will be across southern New England during the first half
of tonight before shifting southward late tonight. Low probability of a brief
shower in the evening...otherwise dry. There is sufficient
moisture in the 850-700 mb layer for mostly cloudy skies with partial
clearing moving in from the north overnight. Cloud cover and
higher dewpoints will result in a middle night with mins mostly in
the 60s...and near 70 bos/pvd and coastal locations.

flow aloft becomes more northwest as northern stream shortwave drops southeast
across Maritimes with cold front moving southward into Maine. Models
show marginal instability developing...but lots of middle level dry
air and lower ki values move in from the north so it should remain
dry with pt-mosunny skies. 850 mb temperatures 16-17c and west/northwest flow will
allow maximum temperatures to approach 90 degrees across much of the
region...a bit cooler near the S coast and higher terrain.
Increasing humidity as well as dewpoints climb into the low and
middle 60s.


Long term /Monday night through Saturday/...

* high confidence in hot and dry weather for much of week
* brief cool Downs mainly in eastern Massachusetts Tuesday and again Friday


Ensembles and 00z models continue to give US high confidence in
upper level ridge building over eastern states this week...
resulting in above normal temperatures through much of period with
mainly dry weather. Hottest days look to be Wednesday and Thursday when highs
should reach well into 80s with lower 90s across parts of CT and
from Merrimack valley into interior southeast Massachusetts. Not looking for
oppressively humid conditions as mean flow should keep dewpoints in
60s although they will approach 70 near S coast...Cape Cod and
islands later in week.

Main items of interest are a couple of backdoor fronts which will
bring slight cooling to east Massachusetts coast. Models in very good agreement
with timing of first front Tuesday...which eventually lifts back north Tuesday
night and Wednesday. 2m temperatures suggest immediate east Massachusetts coast should
stay closer to 80...while highs reach upper 80s in west New England.
Rising heights and associated warm temperatures aloft should act to
suppress convection.

Timing of second backdoor cold front is less certain but looks to be
closer to late Thursday or Friday. This time there may be enough support for
an isolated shower or thunderstorm so kept that mention per model
consensus...especially given fact ridge axis should shift farther S
and west of region.


Aviation /12z Sunday through Thursday/...
forecaster confidence levels...

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

High confidence through Monday.

Patchy fog with MVFR/IFR visibilities will lift by 13z. Otherwise VFR
today with ceilings at or above 060 and brief sprinkle possible. Local
MVFR/IFR visibilities again later tonight and early Monday in patchy valley
fog. VFR Monday.

Kbos terminal...high confidence in taf.

Kbdl terminal...high confidence in taf.

Outlook /Monday night through Thursday/...high confidence.

VFR. Local MVFR/IFR in early morning patchy valley fog. Isolated
shower/thunderstorm possible Thursday.


forecaster confidence levels...

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

Short term /through Monday/...high confidence.

High confidence. Generally SW winds 10-20 knots expected with seas
below Small Craft Advisory.

Outlook /Monday night through Thursday/...high confidence.

Winds and seas below Small Craft Advisory levels through period with
high pressure dominating most of week. Backdoor cold fronts expected
to drop S across waters Tuesday and again late Thursday...shifting winds to
east/NE mainly on east Massachusetts waters...but dry weather should prevail.


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


near term...kjc/jwd
short term...kjc
long term...jwd

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