Area Forecast Discussion
Issued by NWS Boston, MA
Issued by NWS Boston, MA
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FXUS61 KBOX 250638
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
138 AM EST Tue Nov 25 2025
.SYNOPSIS...
High pressure moves offshore today with a warm front bringing a
period of rain from late this afternoon into tonight followed by
mild weather with scattered showers Wednesday into Wednesday evening.
A strong cold front sweeps across the region Wednesday night with
colder and blustery conditions following for Thanksgiving Day. Windy
and cold weather Friday and Saturday, then moderating temperatures
with risk of showers late Sunday into Monday as a frontal system
approaches.
&&
.NEAR TERM /THROUGH TODAY/...
Key Messages...
* Dry to start with increasing clouds. Widespread light rain arrives
by late afternoon into the evening.
Winds have calmed this morning as the center of high pressure passes
just to our south. This high is on its way east and will continue in
that trajectory today, soon replaced by a trough of low pressure
ahead of which we`ll see increasing warm southerly flow. This warm
front lifts north today bringing with it increasing mid and high
clouds and eventually widespread isentropically forced
precipitation. Model guidance, however, indicates a very dry layer
between 950-750mb which will take a while to saturate, so while rain
chances will be on the increase from west to east this
afternoon/evening, wet weather likely doesn`t arrive until late the
late afternoon or evening. This also pushes temperatures several
degrees above normal, in the mid 50s. Stratiform showers overnight
likely drop between a quarter and half inch of rain before exiting
early Wednesday morning as the core of a LLJ shifts offshore and
frontal forcing lifts north.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
Key Messages...
* Widespread showers end early but scattered rain showers continue
through the day.
* Well above average temperatures.
Placed within the warm sector, SNE will see temperatures well above
normal for late November, in the upper 50s to near 60 in spots! The
cold front is slow to arrive, not until after 8pm, so lots of
lingering moisture will mean the continued chance of scattered
showers on Wednesday as the shortwave approaches.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Key Messages...
* Blustery and turning colder late Wednesday night and Thursday.
* Windy and cold Friday into Saturday.
* Becoming unsettled late Sunday into Monday with moderating temps.
Overall looking at a quiet and benign stretch for the Thanksgiving
holiday. The issue of note will be the cold and wind Thursday into
the start of the weekend as Wednesday night`s cold front ushers in a
much cooler post frontal airmass. This cold advection leads to
efficient mixing down of a 35-45 kt LLJ starting Thursday and
peaking Friday into Saturday. Thus, we can expect wind gusts of 20-
30 mph on Thursday, perhaps as high as 30-40 mph on Friday when the
low level jet peaks. Saturday winds come down but remain breezy.
Meanwhile, a much colder airmass is overhead so these winds will
make highs in the 30s and low 40s on Friday feel like the 20s and
low 30s. Overall a dry stretch, though can`t rule out a stray shower
on Friday given the trough/cold pool aloft. By the start of next
week we`re tracking the potential for a pattern change bringing the
return of unsettled weather.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06Z update...
Through 12Z: High confidence.
VFR, increasing coverage of mid to high clouds. Winds
light/variable, then become SW and increase to 5-10 kt late.
Today: High confidence.
VFR with lowering cigs and trending toward MVFR for western
terminals by 00Z late as rain showers approach. SW winds around
10 kt, with possible low level wind shear developing late in
the day as SWly low level winds pick up to around 30-35 kt.
Tonight: Moderate confidence.
Conditions deteriorate to MVFR-IFR in all areas with periods of
4-6 SM in -RA and FG after 00-05Z.
Wednesday: Moderate confidence.
MVFR/IFR in scattered showers. S/SW winds 5-10 kts.
KBOS Terminal...High confidence in TAF.
KBDL Terminal...High confidence in TAF.
Outlook /Wednesday Night through Saturday/...
Wednesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance RA.
Thanksgiving Day through Thursday Night: VFR. Windy with local
gusts up to 30 kt.
Friday through Friday Night: VFR. Windy with gusts up to 30 kt.
Saturday: VFR. Breezy.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Today through Wednesday... High confidence.
* Small Craft Advisory for all southern waters starting Tuesday
night.
* Potential for westerly Gale Force conditions Thursday afternoon
through early Saturday across all waters.
Wind shifts to the southwest on Tuesday with gusts less than 20
knots across all waters and seas between 2 and 4 feet until seas
increase over the southern waters, 4-6 ft Tuesday night.
Outlook /Wednesday Night through Saturday/...
Wednesday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Areas of rough seas. Chance of rain.
Thanksgiving Day: Strong winds with gusts up to 30 kt. Areas of
rough seas.
Thursday Night: Strong winds with gusts up to 35 kt. Rough seas
up to 13 ft.
Friday: Strong winds with gusts up to 40 kt. Rough seas up to
13 ft. Slight chance of rain.
Friday Night: Strong winds with gusts up to 40 kt. Rough seas
up to 13 ft.
Saturday: Low risk for Small Craft Advisory winds with areas of
gusts up to 30 kt. Local rough seas.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 1 AM Wednesday to 1 AM EST Thursday
for ANZ232>235-237-254>256.
&&
$$
SYNOPSIS...BW
NEAR TERM...BW
SHORT TERM...Belk/BW
LONG TERM...BW
AVIATION...BW
MARINE...BW