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Area forecast discussion 
National Weather Service Taunton Massachusetts
143 am EDT Wednesday may 6 2015

Synopsis...
dry weather and mild temperatures will dominate. Little change is
expected through the weekend. A slow moving front may bring
showers and thunderstorms into early next week.

&&

Near term /until 6 am this morning/...

140 am update...

Scattered to broken middle level cloudiness covered areas mainly south
of the Massachusetts Turnpike. Still watching a cluster of rain showers across
southern New York and northern PA. Bulk of this activity should slide
southeast and miss southern New England early this morning.
However...a few brief sprinkles may affect our far southwest
sections mainly in northern CT early this morning. Low temperatures by
daybreak will mainly be in the 40s to the lower 50s.

&&

Short term /6 am this morning through 6 PM Thursday/...
Wednesday...
a moisture-starved shortwave will pass by Wednesday morning. Not
sure if it will track far enough northwest to result in a brief
isolated showers across any portion of our region. Best shot is
northern CT...and perhaps even into part of Rhode Island and southeast Massachusetts
for a short time. Kept the forecast mainly dry across our region.

Otherwise...weak surface high pressure still in place. So once
the sunshine breaks out...we should see temperatures recover into
the 60s and 70s...with the lowest temperatures toward Cape Cod and
the islands. While it will be cooler than the past couple of
days...but these temperatures will still be well above normal.

Wednesday night...
weak surface high pressure keeps conditions dry across southern
New England...with mostly clear skies and light winds.

&&

Long term /Thursday night through Tuesday/...
*/ highlights...

- SW-flow ushering above-average temperatures into the weekend
- perhaps some coastal issues with marine stratus / fog
- increasing rain / thunder chances into early next week
- concern over potential flooding issues

*/ discussion...

Ensembles signal a 500 mb ridging pattern through early next week resulting
in a persistent area of surface high pressure over the NW-Atlantic.
Along its west-periphery SW-flow of warm-moist air maintains ahead of a
slow-moving cool front which based on forecast consensus drags into
S New England by late weekend - early next week.

Moisture-instability axes focus across the NE-Continental U.S. Generating a
conditionally unstable environment /moist-adiabatic through 700 mb/ along
the front where convergence and lift would likely aid with diurnally-
forced shower-thunderstorm activity. Consensus 850 mb-3 flow is rather
weak around 25 miles per hour along with corfidi vector flow even weaker. So
with deep-layer moisture and forecast precipitable waters of 1.50-1.75 inches
wonder whether we will see slow-moving/training activity that
warrants flooding concerns in the future. The warm-cloud layer is
over 10 kft. Could we be seeing heavy-rain processes? Low confidence
at this time. If anything should see upstream activity beforehand
over the weekend that would provide a heads-up. Wet-weather chances
increasing beginning Sunday and going into early next week...no
likely probability of precipitation just yet. As to severe weather potential low confidence
with this aspect as well.

Some intangibles: whether a backdoor cold front will buckle the light snow shower
flow in addition to sea-breezes /pending if interior winds are
light/...and future outcomes of sub-tropical disturbance off the
coast of Florida /as to how and if it will be captured in the flow
towards S New England/. Agree with the previous forecaster that it
may slow the approach of the cool front. Appears as if the slower
forecast guidance should be favored.

Otherwise: warmer than average. May be contending with some marine
stratus / fog at times as higher dewpoint air crosses over the
cooler waters advected by the SW-flow. Could possibly see some
locales around the 90-degree mark on Saturday.

&&

Aviation /06z Wednesday through Sunday/...
forecaster confidence levels...

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

Short term /today through Thursday/...

Today through Thursday...high confidence in VFR conditions through
Thursday. East to southeast sea breezes develop by late morning to
middle afternoon along the immediate coasts. Sea breezes come to an
end by early evening.

Kbos taf...high confidence in taf. East to northeast sea breezes
expected to develop by middle morning and shift to an east southeast
direction by afternoon. Winds will then finally shift to the
southwest by early evening as sea breezes come to an end.

Kbdl taf...high confidence in taf.

Outlook...Thursday night though Sunday...moderate confidence.

VFR. SW-flow. Breezy at times. May have to contend with IFR marine
stratus / fog along the S/se-shoreline terminals during overnight -
morning periods. Increasing chances for -shra towards Sunday.
Possible thunderstorms and rain but low confidence at this time.

&&

Marine...
forecaster confidence levels...

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

Short term /through Wednesday night/...

Through Wednesday...high confidence. Marginal small craft seas
winds/seas are expected to remain below Small Craft Advisory
thresholds through Wednesday night under a weak ridge of high
pressure.

Outlook...Thursday though Sunday...moderate confidence.

Winds and seas remaining below Small-Craft Advisory criteria. Expect
breezy SW-flow ahead of an approaching cool front into Sunday ahead
of which marine stratus / fog may be an issue along the S/se-shore-
line during the overnight into morning periods. Dry forecast overall
with just a chance of shower activity by Sunday.

&&

Fire weather...
mainly dry weather with little appreciable rainfall will continue
through at least Saturday if not into Sunday/Monday. While winds
for the rest of the work week will probably not be strong enough
for fire weather headlines...we may have to be more concerned by
Saturday. There will be at least a bit more potential for some
marginal fire weather headline wind gusts.

&&

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

&&

$$

Synopsis...Belk/sipprell
near term...Frank
short term...Belk/nmb
long term...sipprell
aviation...Frank/sipprell
marine...Belk/sipprell/nmb
fire weather...staff

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