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Area forecast discussion
National Weather Service Boston/Norton Massachusetts
638 PM EST Wed Nov 13 2019

Synopsis...
high pressure building in from the west will become centered
over New England tonight. It will bring record cold temperatures
today, along with gusty winds this morning. As the high moves
off the coast, temperatures begin to moderate on Thursday, but
will still be below normal for the middle of November. Even
milder weather is forecast for Friday, but then another strong
cold front will deliver unseasonably cold temperatures Friday
night through Saturday night. An ocean storm may impact the
region Sunday night into Monday.

&&

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

700 PM update...

Winds are already coming down thanks to incoming high pressure. Not
expecting ideal radiational cooling conditions with some higher
clouds arriving after midnight from west to east. Low
temperatures Thursday morning will be well below normal,
possibly even new records in some cases. Should these clouds
arrive later than currently thought, lower temperatures would be
more likely.

Dry weather prevails.

&&

Short term /6 am Thursday morning through Thursday night/...
high pressure moves offshore. Winds become light southerly,
which would also result in a slight increase in lower level
humidity. This layer of increased humidity is very shallow and
low, so the most likely outcome would be drizzle or very light
showers. Temperatures will be critical to determining
precipitation type. Not much humidity in the dendritic growth
zone, so thinking rain or freezing rain or drizzle will be most
likely. Based on current timing, most of any precipitation
should be rain during Thursday.

The warm advection pattern continues into Thursday night,
leading to a continued risk for showers Thursday night across
southeastern New England. More cloudiness should result at a
minimum.

This aspect or precipitation type will need to be monitored
closely with later forecasts. Temperatures remain below normal
through this period.

&&

Long term /Friday through Wednesday/...
highlights...

* mainly dry with seasonable temps Fri
* turning much colder again Fri night into Sat night
* an ocean storm may impact southern New England Sun night/Mon with rain and coastal
wind along with pockets of ice or snow possible across the interior

Friday into Saturday...

Still appears a robust mid level low/shortwave moves across
southeastern Canada and northern New England. While the parent
low pressure should remain to our north, a strong cold front
should push through our region later Friday. Expecting much
colder air to arrive Friday night into Saturday, but not quite
as cold as we were Wednesday morning. Gusty north winds will result
in wind chills in the single numbers and teens late Friday
night and Saturday morning. Expecting a mainly dry frontal
passage Friday night with mostly sunny skies Saturday.

Sunday into Wednesday...

It appears dry weather will hang on through Sunday as high
pressure lingers across northern New England and the Maritimes.
This should delay the arrival of moisture associated with a low
pressure meandering up the coast. Lots of track and timing
uncertainty remains with respect to this low pressure.
Maintained a rather broad period of precipitation chances from
late Sunday into Wednesday. However, thinking it will not be
precipitating this entire time. Forecast changes are likely with
later forecasts.

Based on timing, some icing, or even snow, will be a concern at
times. More details with later forecasts.

&&

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

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

00z update...

Short term /through Thursday night/...

Tonight...high confidence. VFR.

Thursday...moderate confidence. VFR early. Then MVFR ceilings
developing with areas of drizzle and light rain showers in the
afternoon, possibly mixed with snow in central and northeast Massachusetts.
Local IFR possible late in the day.

Thursday night...moderate confidence. Mainly VFR, with local
MVFR possible in -shra. Breezy towards the coasts.

Kbos terminal...high confidence in taf.

Kbdl terminal...high confidence in taf.

Outlook /Friday through Monday/...

Friday: VFR. Breezy.

Friday night through saturday: VFR. Windy with gusts up to
35 kt.

Saturday night: VFR. Breezy.

Sunday: mainly VFR, with areas MVFR possible. Windy with local
gusts up to 30 kt. Slight chance rain.

Sunday night: mainly VFR, with areas MVFR possible. Windy with
gusts up to 35 kt. Chance ra, chance snow.

Monday: mainly VFR, with areas MVFR possible. Windy with gusts
up to 30 kt. Chance rain.

&&

Marine...
short term /through Thursday night/...high confidence.

High pressure builds over the waters tonight through Thursday.
Winds and seas diminish as this high pressure passes by.
Increasing southwest winds Thursday into Thursday night, which
will lead to building seas.

Thinking the small craft advisories can be terminated over the
course of this evening. Additional small craft advisories will
likely be needed for some of the waters Thursday night,
especially the outer coastal waters.

Low risk for scattered showers Thursday into Thursday night.
Showers could be strong enough to reduce visibility, but should
remain above 3 nm.

Outlook /Friday through Monday/...

Friday: winds less than 25 kt. Areas of seas approaching 5 ft.
Slight chance of rain showers.

Friday night: low risk for gale force winds with gusts up to
35 kt. Areas of rough seas.

Saturday: strong winds with gusts up to 35 kt. Rough seas up to
10 ft.

Saturday night: moderate risk for Small Craft Advisory winds
with local gusts up to 30 kt. Rough seas up to 10 ft.

Sunday: strong winds with gusts up to 35 kt. Rough seas up to
11 ft. Slight chance of rain.

Sunday night through monday: low risk for gale force winds with
gusts up to 35 kt. Rough seas up to 12 ft. Chance of rain.

&&

Climate...
record low min temps for Wednesday Nov 13

Boston 14/1883
Hartford 18/2001
Providence 19/2019 - previously 20/2001
Worcester 13/2019 - previously 15/1986

Record low Max temps for Wednesday Nov 13

Boston 33 - 36/1874
Hartford 32 - 33/1911
Providence 32 - 37/1911
Worcester 26 - 32/1962,2013

Record low min temps for Thursday Nov 14

Boston 16/1905
Hartford 15/1986
Providence 16/1905
Worcester 10/1986

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...Small Craft Advisory until midnight EST tonight for anz250-254-
255.

&&

$$
Synopsis...Belk
near term...Belk/bw
short term...Belk

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