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Area forecast discussion
National Weather Service Taunton Massachusetts
641 PM EST Wed Jan 17 2018

Synopsis...
snow showers will come to an end early this evening. Dry, but
cold air will move into southern New England tonight and into
tomorrow. Mainly dry weather expected tonight into Sunday, with
a warming trend during this weekend. Another low pressure should
affect the region early next week with mostly rain, but there is
a risk of some snow/mix/ice across the interior.

&&

Near term /until 6 am Thursday morning/...
snow showers will continue to diminish this evening as a coastal
low moves towards the Gulf of Maine. An approaching shortwave
will also help to keep some light snow showers going for a few
more hours, especially across Rhode Island and eastern Massachusetts. Only light
additional snow accumulations up to one inch are expected.

No major changes to the forecast this evening. Did try to time
the ending of the light snow better. Also tweaked temperatures
based upon observed trends.

Previous discussion...

This shortwave will push through the region tonight resulting in a
end of any precipitation tonight. Mid-level winds will turn more to
the northwest allowing for cold dry air to push into the region.
Overnight temps will generally be in the teens with low 20s near the
urban corridor and coastline. If locations decouple tonight then
temps could drop quickly into the single digits thanks to fresh snow
pack and clear skies. Highest confidence is across Oregon and baf.

&&

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

Strong high pressure will build across the Mississippi Valley region
pushing a coastal low off the virgina coastline. Up here in the
northeast, Flat Ridge from the southern high pressure system will be
in place. Continued westerly flow across the area as high
temperatures will be near normal, reaching the upper 20s to mid 30s.
Dry weather for the day with plenty of sunshine. Guidance is hinting
at some ocean effect clouds moving in during the afternoon, as well
as over the Berks from any les.

&&

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

* dry with a warming trend through this weekend
* another storm may bring mostly rain late Monday into Tuesday
with a risk of some interior snow/mixed precip/ice

Quiet pattern expected through this weekend with a moderating
trend as amplified trough moves into the plains with downstream
ridging and rising heights across New England. Near normal
temperatures Friday, becoming above normal during this weekend.

A deeper mid level trough is expected to approach southern New
England early next week. This will steer a low pressure into the
Great Lakes, and a cold front across our region. There is a
decent southerly low level jet, so moisture transport should
also be slightly higher than normal. Temperatures are marginal
for wintry precipitation, so it will all come down to timing.
The more precipitation which occurs during the nighttime hours,
the more likely portions of our region could see a period of
snow, sleet or freezing rain. During the daytime hours, rain is
much more likely. Will take several days for these sorts of
details to become clearer.

&&

Aviation /00z Thursday through Monday/...
forecaster confidence levels...

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

Short term /through Thursday/...

Tonight...high confidence. VFR out west to start. Any lingering
MVFR-IFR conditions improving to VFR across Rhode Island/east mass by around
18/05z or so.

Thursday...high confidence. VFR. Northwest winds gusting up to 20 kts
across S coastal areas, Cape Cod and the islands.

Kbos terminal...moderate confidence in taf. Improving conditions
to MVFR by the evening with VFR after midnight.

Kbdl terminal...high confidence in taf. Conditions should start
to improve within the next few hours as precip tapers off.

Outlook /Thursday night through Monday/...

Thursday night: VFR. Breezy.

Friday: VFR.

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

Saturday: VFR. Windy with gusts to 35 kt.

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

Sunday through Sunday night: VFR.

Monday: mainly VFR, with local MVFR possible. Chance rain.

&&

Marine...
forecaster confidence levels...

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

Short term /through Thursday/...high confidence.

Coastal low will push into the Gulf of Maine tonight switching the
winds to a more northwest direction. A few gusts to near 20 kts but
overall winds will be below Small Craft Advisory. Seas will remain at or above 5 feet
through much of the period for the outer open waters. Thus have
extended the Small Craft Advisory into Thursday evening.

Outlook /Thursday night through Monday/...

Thursday night: winds less than 25 kt. Seas up to 5 ft.

Friday: winds less than 25 kt. Areas of seas approaching 5 ft.

Friday night: low risk for Small Craft Advisory winds with
local gusts up to 30 kt. Areas of seas approaching 5 ft.

Saturday: moderate risk for gale force winds with gusts up to
40 kt. Areas of rough seas.

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

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

Sunday night: winds less than 25 kt. Seas locally approaching
5 ft.

Monday: winds less than 25 kt. Slight chance of rain.

&&

Hydrology...
1100 am update...

A Flood Warning remains in effect for the Connecticut River at
Middle Haddam, where ice jams are causing river fluctuations.

Cold conditions will persist through midweek which will limit
additional runoff. Continued ice jams will remain on some of the
rivers. There will be some increase of snow pack across interior
southern New England as well.

For details on specific area rivers, including observed and
forecast river stages, please visit the advanced hydrologic
prediction service (ahps) graphs on our website.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...Small Craft Advisory until 8 PM EST Thursday for anz250-
254>256.
Small Craft Advisory until 7 am EST Thursday for anz251.

&&

$$
Synopsis...Belk/dunten
near term...Belk/dunten

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