Area Forecast Discussion
Issued by NWS Boston, MA

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943
FXUS61 KBOX 230700
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
200 AM EST Sun Nov 23 2025

.SYNOPSIS...
Few passing showers or flurries are possible today as an upper level
disturbance moves through, then high pressure returns Monday. A warm
front will bring a period of rain from late Tuesday into Wednesday
morning, mild with a continued chance of showers Wednesday into
Wednesday night ahead of an approaching cold front. Cooler and
blustery conditions follow behind the front for Thanksgiving Day,
then windy and cold weather for next Friday and Saturday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Key Messages:

* Isolated pop up showers today with snow mixing in for the high
  terrain

Shortwave trough and weak cold front exit the Great Lakes this
morning, moving through the region this afternoon into tonight.
Modest upper-level forcing via PVA and mid-level moisture will lead
to scattered rain showers much of the afternoon and evening.  Snow
will mix in across the interior, mainly north and west Worcester, as
dry air near the surface will keep wetbulb temps near or below
freezing, even with actual temperatures in the upper 30s.  Unlikely
to see any accumulating snow outside the highest terrain in the
northern Berkshires, where temps will be cold enough to keep rain
from mixing in.  As for rain accumulations, showers will be light,
only dropping a couple of hundredths of an inch. Highs across the
region will top out in the upper 30s to low 40s with SW winds around
5-10 mph.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
Tonight:

Remaining showers exit offshore by midnight with drying and clearing
conditions thereafter.  Winds remain elevated overnight out of the
west at 5-10mph, which will help keep overnight lows from bottoming
out in the low 20s, instead staying in the upper 20s to low 30s.

Monday:

An upper-level ridge and surface high pressure bring back sunny
skies to the region at the start of the short workweek.  850mb Temps
warm from -5C to +2C, helping high temps jump into the upper 40s to
low 50s.  The warming temps bring a return to breezy conditions with
WNW winds at 10-15mph for Monday afternoon.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Key Messages:

* Dry and seasonable Tuesday. Rain Tuesday night into Wednesday as a
  warm front lifts across the region, turning mild with showers for
  Wednesday afternoon.

* Cooler conditions return Thursday into this weekend, along
  with a lower chance of rain and snow showers, and breezy
  conditions.

Overview: Tuesday the trough axis shifts east of New England and the
mid-level heights increase with a 1025mb surface high southwest of
the region. Rain arrives late Tuesday into Wednesday morning due to
a warm frontal passage, showers continue into Wednesday along with
mild conditions as southern New England is firmly placed in the warm
sector. A robust shortwave and cold frontal passage Wednesday night
into early Thanksgiving morning. The trough becomes cut off across
the high latitudes late Thursday into Friday, and moves to the
Canadian Maritimes this coming weekend. Passage of the cold front on
Thanksgiving leads to CAA and a period of gusty west-northwest wind
on both Thursday and Friday, as the magnitude of the 850mb jet
increases between 40 and 55 knots. High pressure returns for the
start of next weekend with diminishing winds.

Precipitation: Mentioned above, the next chance for rain arrives on
Tuesday during the late afternoon to early evening with the passage
of a warm front. Southwesterly 850mb winds transport higher moisture
with PWATs increasing up to an inch and there is growing confidence
there will be enough assent to support those widespread shower into
the overnight hours, ending early Wednesday morning. Rain becomes
showery for Wednesday as the region remains in the warm sector. As
for rainfall, not expecting any significant totals at this time. The
probabilities of 0.5" or more are roughly 40 to 60 percent. The cold
front moves through overnight and exits early Thanksgiving morning.
As temperatures fall, upslope snow flurries are possible across the
high terrain of northern and northwest Massachusetts. PWATs fall
considerably behind the front, but a persistent west-northwest flow
could allow for lake effect snow showers to come off the eastern
Great Lakes, leading to periods of festive flurries in far western
areas. Otherwise, dry weather prevails into this coming weekend as
high pressure develops.

Temperatures:

A brief warmup is anticipated Tuesday and especially Wednesday as the
flow aloft turns to the southwest, 925mb temperatures reaching near
+12C by Wednesday afternoon! Expecting seasonal conditions Tuesday
as highs reach the low to middle 50s, with upper 40s in the high
terrain. Wednesday feels spring-like as highs top off near 60F
across the coastal plain while the rest of the region are in the
upper and middle 50s. Behind the cold front, 925mb temperatures fall
to 0C on Thanksgiving, and then -5C to -3C for Friday and Saturday.
Cooler for Thanksgiving day, with highs in the upper 40s near the
coast and lower 40s across the high terrain. Friday and Saturday are
chilly with highs in the low 40s to upper 30s. Mind you, there will
be a gusty west-northwest wind which will make it feel as if it were
below freezing both afternoons. As for nighttime lows, there is no
significant cold on the horizon, lows are at or above freezing
Tuesday and Wednesday night, then sub-freezing lows Thursday night
through Saturday night.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

06z TAF Update:

Rest Tonight: High confidence.

VFR. Patchy ground fog possible in low lying areas. Light NW
winds under 5 knots.

Sunday: High confidence

VFR with periods of MVFR possible in the afternoon. Isolated
rain showers pop up in the afternoon and continue into the
evening. Snow may mix in with rain for the interior high
terrain including ORH. Accumulation will be light, so opted to
use VCSH for all TAFs except for the Cape and Islands where a
developing low pressure center gives a better chance for more
then a trace of precip. Winds turn SW at 5-10 knots.

Sunday Night: High confidence.

VFR with periods of MVFR possible through about 06z. Lingering
showers move offshore by 03z. Winds increasing from the west at
5-10 knots.

Monday: High Confidence

VFR. Increasing west winds at 10-15 knots.

KBOS Terminal...High confidence in TAF.

VFR. Isolated pop up showers possible this afternoon.

KBDL Terminal...High confidence in TAF.

VFR. Isolated pop up showers possible this afternoon.

Outlook /Monday Night through Thursday/...

Monday Night: VFR.

Tuesday: Mainly VFR, with local MVFR possible. Breezy. Chance
RA.

Tuesday Night: MVFR/IFR conditions possible. Breezy. RA.

Wednesday: Mainly VFR, with local IFR possible. Chance RA.

Wednesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance RA.

Thanksgiving Day: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Today through Monday... High confidence.

Weak clipper system moves through the Saint Lawrence Valley before
ejecting into the Gulf of Maine early Monday morning. With limited
moisture, not expecting any significant precipitation during this
time, but cannot rule out a spot shower/flurry.

Seas and southwesterly wind remain below advisory criteria today and
tonight. Wind becomes northwesterly on Monday with wind gusts on the
outer waters increasing, between 20 and 25 knots. Seas are building
too on the southern most outer waters, between 4 and 6 feet.

As conditions are marginal, over a limited area (mainly for the
southern outer water south of Block Island), and peak boating season
has passed, opt`d to not issue an advisory at this time.

Outlook /Monday Night through Thursday/...

Monday Night: Winds less than 25 kt.

Tuesday: Winds less than 25 kt. Slight chance of rain.

Tuesday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Rain.

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft. Rain likely.

Wednesday Night: Winds less than 25 kt. Local rough seas.
Chance of rain.

Thanksgiving Day: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.

&&

$$

SYNOPSIS...Dooley/KP
NEAR TERM...KP
SHORT TERM...KP
LONG TERM...Dooley
AVIATION...Dooley/KP
MARINE...Dooley/KP