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Area forecast discussion
National Weather Service Taunton Massachusetts
issued by National Weather Service Upton New York
1017 PM EST Tue Jan 23 2018

Synopsis...
drier air works into the region behind a cold front overnight.
Blustery, dry and colder weather follows Wednesday through
Friday, then a warming trend next weekend. A cold front may
bring showers next Sunday or Monday.

&&

Near term /until 6 am Wednesday morning/...
will continue to dry out lower to middle portions of the
atmosphere overnight as northern stream shortwave trough axis
pivots tot the northeast, with quasi-zonal flow setting up
aloft. As a result, expect a decrease in cloud cover overnight
and any fog, mainly over higher elevations, to dissipate by
shortly after midnight.

Otherwise...low temps by daybreak will fall back into the upper
20s to the middle 30s.

&&

Short term /6 am Wednesday morning through 6 PM Wednesday/...
Wednesday...

A west northwest flow of more seasonable temperatures will be
working back into the region on Wednesday. High temps will not
recover too much...generally remaining in the 30s to near 40 across
parts of the coastal plain. Should be at least partial
sunshine...but do expect some strato-cumulus clouds that will be
focused across the interior. West to northwest winds will gust to
between 25 and 30 mph at times.

&&

Long term /Wednesday night through Tuesday/...
highlights...

* dry but cooler weather for the rest of the work week
* above average temperatures for Saturday and Sunday
* next shot of wet weather will be around sun/Mon

Overview...

12z guidance is in general agreement with the upcoming medium and
long range. Progressive pattern over the region as ongoing upper
level trough will push offshore as mid-level ridge builds into the
area by the weekend. For the end of the period, still some
uncertainty regarding the timing and amplitude of the upper level
trough moving from the northern plains towards the East Coast sun
into Monday. GFS continues to be on the faster side of the envelope
compared to the ec and UKMET. If the guidance continues to trend
towards the slower envelope, than there is the potential for a more
significant surface low to develop. This could result in warmer
temps for the weekend, and heavier rainfall. If it is weaker, than
cannot rule out some trapped cold air resulting in p-type issues.
Still a lot of uncertainty and will trend towards a blend of the
guidance until details can be sorted.

Wednesday night into Friday...high confidence.

Building high pressure across the southeast will build across the US
East Coast resulting in dry weather through the period. Still some
thermal gradients in the mid-levels as upper level shortwave passes
through on Thursday. This will result in a breezy but chill day.
Temperatures will still be in the 30s on Friday, but with less winds
should make it feel warmer. Some mid-level moisture around 850-700mb
will help bring in some clouds but overall a pleasant January day is
on tap.

Saturday into Monday...moderate confidence.

Subtropical ridge will build across the US East Coast over the
weekend as northern stream system approaches the northeast. All
guidance as well as the ensembles are indicating precipitation for
the area. Biggest uncertainty is the amount, exact timing and if
all precip will be liquid. Current forecast is an ongoing blend of
the guidance with a trend towards the UKMET and ec. Thus expect
precipitation to move into the area on Sunday as mostly rain and
temperatures will be well above average thanks to southerly low level jet.
If precip lingers into Monday, cold air advection behind the system could switch
any precip to snow, but overall confidence is low that this will
occur. Will need better guidance to see this potential.

&&

Aviation /03z Wednesday through Sunday/...
forecaster confidence levels...

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

Short term /through Wednesday/...

Overnight...moderate to high confidence. Conditions improve to
VFR throughout by 06z. Some marginal MVFR cigs may work back
into the region after midnight in the cold air advection pattern...mainly
across the interior.

Wednesday...moderate to high confidence. Mainly VFR but some brief
marginal MVFR cigs possible for a time in the interior. West-west-northwest
winds gusts of 20 to 30 knots.

Kbos terminal...moderate to high confidence in taf.

Kbdl terminal...moderate to high confidence in taf.

Outlook /Wednesday night through Sunday/...

Wednesday night through thursday: VFR. Breezy.

Thursday night: VFR. Windy with local gusts to 30 kt.

Friday: VFR. Breezy.

Friday night: VFR.

Saturday: VFR. Windy with gusts to 30 kt.

Saturday night: mainly MVFR, with areas VFR possible. Breezy.
Chance rain.

Sunday: mainly MVFR, with areas IFR possible. Breezy. Rain
likely.

&&

Marine...
forecaster confidence levels...

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

Short term /through Wednesday/...
minor changes were made with this update to reflect the latest
trends in observations and guidance. The forecast appears on
track.

Overnight...high confidence. Have converted the gale warnings
to Small Craft Advisory with low level jet pushing east of the waters. May see a temporary
lull in the winds...but they will pick back up after midnight
with west-southwest gusts of 25 to 30 knots developing in the cold air
advection pattern.

Wednesday...high confidence. West-northwest wind gusts of 25 to 30 knots in
the cold air advection pattern. Small Craft Advisory headlines will be needed for
most waters.

Outlook /Wednesday night through Sunday/...

Wednesday night: low risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft.

Thursday: moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Seas up to 5 ft. Chance of freezing spray.

Thursday night: moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Areas of rough seas. Chance of freezing
spray.

Friday: low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas locally approaching 5 ft.

Friday night: winds less than 25 kt.

Saturday: low risk for Small Craft Advisory winds with gusts up
to 30 kt. Local rough seas.

Saturday night: winds less than 25 kt. Local rough seas. Chance
of rain.

Sunday: winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...Small Craft Advisory until 6 PM EST Wednesday for anz230>237-
250-251-254>256.

&&

$$
Synopsis...

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