Area Forecast Discussion
Issued by NWS Boston, MA

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414
FXUS61 KBOX 252351
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
651 PM EST Tue Nov 25 2025

.SYNOPSIS...
A warm front brings a period of steady rain into tonight,
followed by mild temperatures Wednesday into Wednesday night.
Low pressure passing well to the north swings a strong cold
front through our region late Wednesday night. Colder and
windier conditions follow behind this front Thursday through
Saturday. Milder temperatures Sunday, before another frontal
boundary approaches from the west early next week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...

* Increasing temperatures overnight with widespread showers

Thinking the overall trend of the forecast remained on track.
The main change this evening was to slow the eastward progress
of the rain shield by 1-2 hours. Also brought temperatures back
in line with observed trends.

Previous Discussion...

A surface warm front will lift through southern New England
tonight with widespread steady/light rain. Low temperatures
will likely bottom out in the mid to upper 40s around midnight
before temperatures begin to increase in response to the warmer
air pass advecting in from the south. Dewpoints increase as well
to the low- mid 50s which will also help support the warming
temperatures overnight. Could see some patchy fog develop, but
surface winds should be strong enough to suppress any widespread
or dense fog. Expect a good soaking overnight with 0.25 to 0.5
inches across the region.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
TOMORROW AND TOMORROW NIGHT

Key Messages

 * Isolated to scattered showers on Wednesday
 * Cloudy with above normal temperatures upper 50s to low 60s

Showers associated with surface low pressure moving over the
Northeast diminish for a time tomorrow morning as a warm
sector air mass moves over our region. Strong synoptic forcing
will continue to support precipitation chances for much of the
day, but a mid-level dry slot will suppress any widespread/
persistent precipitation tomorrow. Expecting mainly isolated to
scattered light showers. Conditions will be muggy for mid-
November with temperatures and dewpoints in the upper 50s to
lower 60s. Any shower activity should begin to wane during the
mid-afternoon hours.

Tomorrow a night, a surface cold front pushes through region
with 925 hPa temps plummeting to -5C. This will result in
cold/blustery conditions tomorrow night into Thanksgiving
morning with lows generally in the mid to upper 30s. Winds
become westerly from 10-20 mph with some higher gusts.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Key Messages...

* Colder and Blustery Thursday - Saturday
* Slight chance of snow showers Friday mainly in the higher terrain
* Moderating temps with an increasing chance for precipitation
  for the second half of the weekend


Still looking dry albeit colder and blustery for the
Thanksgiving holiday. The cold and gusty conditions look to
continue through Saturday as a much colder airmass moves in.
Strong cold advection behind frontal passage allows for
steepening lapse mid and low level lapse rates early Thurs
morning. Increasing pressure gradient behind departing low
pressure strengthens the LLJ to 30-40kts thus gusts rise to as
high as 30-35 mph Thursday afternoon. Strongest winds arrive
Friday as the LLJ increases to 45-50kts. Expecting widespread
gusts to 35-45 mph especially in the higher terrain. Winds wind
down Saturday as high pressure moves overhead but remain breezy.


As mentioned earlier, Wednesday night`s frontal passage will
usher in a much colder airmass with 850 mb temps falling as low
as -10C Friday into Saturday. Surface high temps will struggle
to rise into the lower 40s for much of the area, and perhaps
even the mid 30s for the higher terrain. Coldest temps will
likely be Sunday morning if mid and high level clouds can hold
off until closer to sunrise. Should be mainly dry for most
locations through the weekend, though we can`t rule out areas of
snow showers Friday with any lake effect streamers. Better
chance for meaningful precipitation arrives later Sun into Mon
with an approaching frontal boundary.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

Tonight...High Confidence in trends

MVFR ceilings and RA overspread the region. Ceilings eventually
fall to IFR/LIFR between 03-06Z with MVFR/IFR vsbys in RA.

Tomorrow...High confidence in trends, moderate in timing

RA comes to an end by 12Z. Additional scattered showers possible
for much of the day tomorrow, but most terminals stay dry,
especially after 18Z. IFR persists through tomorrow morning,
with some improvements to VFR/MVFR ceilings possible by 15-17Z.

Tomorrow Night...High Confidence

Cold front crosses the region tomorrow and clears skies from
west to east between 00Z and 06Z. Winds shift to the west from
10 to 15 knots with some 25 knot gusts possible near the coast.

KBOS Terminal...High confidence in TAF.

Expect RA at BOS between 00-02Z with conditions deteriorating
to IFR by 08Z. Possible we see some further deterioration to
LIFR if an onshore flow develops, but right now thinking
south/southwest winds should fend off ceilings below 500 feet
for most of this time.

KBDL Terminal...High confidence in TAF.

Outlook /Thursday through Sunday/...

Thanksgiving Day: VFR. Windy with gusts up to 30 kt.

Thursday Night through Friday Night: VFR. Windy with gusts up
to 35 kt.

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

Saturday Night: VFR.

Sunday: Mainly VFR, with areas MVFR possible. Breezy. Chance
RA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Wednesday Night...High Confidence

A low pressure moves over the coastal waters tonight with a
period of steady rain. Increasing dewpoints may result in
localized dense fog development over the cooler ocean waters.
Showers and fog dissipate tomorrow night into Thursday as a cold
front crosses the waters with a much cooler/drier air mass.

Outlook /Thursday through Sunday/...

Thanksgiving Day: Low risk for gale force winds with gusts up
to 35 kt. Areas of rough seas.

Thursday Night: Moderate risk for gale force winds with gusts
up to 35 kt. Areas of rough seas.

Friday: Moderate risk for gale force winds with gusts up to
40 kt. Rough seas up to 12 ft. Slight chance of rain.

Friday Night: Strong winds with gusts up to 40 kt. Rough seas
up to 13 ft.

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

Saturday Night: Winds less than 25 kt.

Sunday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Chance of rain.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Gale Watch from Thursday evening through Friday evening for
     ANZ230-236.
     Gale Watch from Thursday afternoon through Saturday morning
     for ANZ231>235-237-250-251-254>256.
     Small Craft Advisory from 1 AM Wednesday to 1 AM EST Thursday
     for ANZ232>235-237-254>256.

&&

$$

SYNOPSIS...RM
NEAR TERM...Belk/RM
SHORT TERM...Belk/RM
LONG TERM...FT/RM
AVIATION...Belk/BW/RM
MARINE...BW/RM