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Area forecast discussion 
National Weather Service Taunton Massachusetts
1001 am EDT Thursday Jul 31 2014

a few hit and miss showers/thunderstorms are expected this afternoon
and again Friday afternoon...mainly northwest of I-95. The weekend
forecast remains uncertain but the potential for a period of wet
weather continues. Seasonable temperatures are then expected early next


Near term /until 6 PM this evening/...
***a few strong thunderstorms are possible this afternoon northwest
of I-95***

10 am update...scattered light showers/sprinkles falling out of
middle deck clouds crossing interior southern New England. Minor
adjustments to sky cover and probability of precipitation a bit eastward...otherwise
forecast looks on track. Previous discussio follows.

A potent shortwave Wills move across northern New England today.
While the best dynamics/forcing will pass to our north...still
expect to see some least across our northwest zones.
Latest guidance shows that convective available potential energy on the order of 500 to 1000 j/kg
will combined with 0 to 6 km shear values on the order of 40 to 45
knots. In addition...500 mb temperatures drop to around -16c in our
northwest zones...which is very impressive for this time of year.

Expect to see a few hit and miss showers/thunderstorms develop
northwest of I-95 this afternoon. A few of the storms may become
strong producing hail and gusty winds given the above parameters.
Highest risk for this will be across northwest Massachusetts/southern New Hampshire
between noon and 6 PM. We also can/T rule out an isolated severe
thunderstorm or two as sometimes these cold pools can over
perform...despite marginal instability. Meanwhile...expect the
weather to generally remain dry southeast of I-95 as those locations
will be removed from the bulk of the forcing.

A mixture of clouds and sun will result in high temperatures in the upper
70s and lower 80s this afternoon.


Short term /6 PM this evening through 6 PM Friday/...

Any left over showers/thunderstorms should quickly dissipate early
this evening as shortwave departs and instability diminishes. Low
temperatures will mainly be in the the lower 60s.


A mixture of clouds and sun anticipated with high temperatures mainly in
the lower 80s. Another shortwave should trigger a few hit and miss
showers/thunderstorms during the afternoon...mainly to the northwest
of I-95. Shear is less than today and 500 mb temperatures are not nearly
as storms will probably be weaker than what is expected


Long term /Friday night through Wednesday/...
* steady rain likely sometime this weekend
* showers and thunderstorms possible early next week

The models are in fairly good agreement through the long term.
However...there are definitely differences both in the details and
also in parts of the synoptic pattern...particularly around the
potential system for the weekend. Used a blend of available
guidance for much of the forecast.

Saturday and Sunday...the trough shifts a bit to the west over the
weekend allowing for subtropical moisture to move up the East Coast.
This allows a stationary front off the coast to shift west over
southern New England. Combined with the moisture...expect a fairly
steady rainfall across at least a portion of southern New England
through part of the weekend. There are still differences in the
models both in the westward extent of the front and in the timing so
this could occur Saturday...Sunday...or a portion of both days and
across the entire area...only on the South Coast or anywhere in

Monday and Tuesday...stationary front slowly shifts back offshore
bringing an end to the steady rainfall. However...low pressure
moving through Quebec will bring a cold front towards southern New
England. Expect the possibility for showers and thunderstorms

Wednesday...high pressure builds in behind the cold front. Cooler
but quiet weather is expected.


Aviation /14z Thursday through Monday/...
forecaster confidence levels...

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

Short through Friday...

Today...high confidence in mainly VFR conditions. A few hit and
miss showers/thunderstorms expected this afternoon...mainly to the
north and west of I-95 with the highest risk across northwest
Massachusetts/southwest New Hampshire. This activity may result in briefly lower

Tonight...moderate to high confidence. Mainly VFR conditions other
than patchy ground fog possible late in the typically prone

Friday...high confidence in mainly VFR conditions. A few hit and
miss showers and thunderstorms possible during the
afternoon...mainly northwest of I-95. This activity may result in
briefly lower conditions.

Kbos taf...high confidence in VFR conditions with moderate
confidence that a southeast sea breeze develops for a few hours this
afternoon. Very low probability for a thunderstorm moving over the
terminal this afternoon.

Kbdl taf...high confidence in taf. Low probability for a brief
thunderstorm to move across the terminal this afternoon.

Outlook...Friday night through Monday...

Friday night through Sunday...moderate confidence. Mainly VFR
northwest...chance for MVFR ceilings/visibilities in scattered showers. MVFR
conditions more probable towards eastern Massachusetts/Rhode Island in -shra.

Monday...moderate confidence. Mainly VFR. Low probability of
MVFR/IFR conditions in scattered -shra/tsra.


forecaster confidence levels...

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

Short through Friday...

High confidence. Upper level ridge just east of the waters will keep
winds/seas below Small Craft Advisory levels through Friday
afternoon with good visibilities.

Outlook...Friday night through Monday...

High confidence. Quiet boating weather expected with high pressure
over the waters. Rain is likely through Sunday with a wavering
stationary front near or over the waters.


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


near term...Frank/rlg/nmb
short term...Frank
long term...rlg

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