Area Forecast Discussion
Issued by NWS Boston, MA

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273
FXUS61 KBOX 251819
AFDBOX

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

.SYNOPSIS...

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

&&

.NEAR TERM /THROUGH TONIGHT/...
TONIGHT

* Increasing temperatures overnight with widespread showers

A surface warm front will lift through southern New England tonight
with widespread steady/light rain. Low temperatres 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/dense fog. Expect
a good soaking overnight with 0.25 to 0.5 inches across the region.
&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
TOMORROW AND TOMORROW NIGHT

Key Messages

 * Isolated to scattered showers on Wednesady
 * 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 the 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. Expect mainly isolated to scattered light
showers. Conditions will be muggy for mid-November with temperautres
and dewpoints in the upper 50s to low 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 MONDAY/...
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 precipiation 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 /18Z TUESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

18Z update...

Rest of Today

Overcast VFR with modest south/southwest winds around 10 knots.
Some 20+ knot gusts near the coast. -RA/RA moves in from west to
east between 21-00Z along with MVFR ceilings.

Tonight...High Confidence in Trends

MVFR ceilings and RA overspread the region after 00Z. 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 persist through tomorrow afternoon
with some improvements to VFR/MVFR ceilings possible by 00Z

Tomorrow Night... High Confidence

Cold front crosses the region tomorrow and clears skies from
west to east between 00 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 condition deteriorating to
IFR by 06Z. 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.

KBDL Terminal...High confidence in TAF.

Outlook /Thursday through Saturday/...

Wednesday Night: Mainly VFR, with local IFR possible. Windy
with local gusts up to 30 kt. Chance RA, patchy BR.

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.

&&

.MARINE...
Forecaster Confidence Levels...

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

Tonight through Tomorrow Night...High Confidence

An area of low-pressure moves over the coastal waters tonight with
a period of steady rain.  Increasing dewpoint 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. Gale
force gusts may develop as early as Thursday morning over the
southern marine zones. Gusty west winds will persist through
Saturday. A Gale Watch goes into effect Thursday afternoon

Outlook /Thursday through Saturday/...

Wednesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Areas of rough seas. Chance of rain,
patchy fog. Areas of visibility 1 to 3 nm.

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.

&&

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