383
FXUS61 KBOX 191811
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
111 PM EST Wed Nov 19 2025

.SYNOPSIS...
Aside from some rain later Friday into Saturday ahead of a cold
front, dry and seasonably cool weather will prevail through
early next week as high pressure dominates our weather.

&&

.NEAR TERM /THROUGH TONIGHT/...
Updated 1230 PM Wed

Key Messages:

* Clearing along South Coast, setting up a cold night.

Showers south of New England were moving farther out to sea as
low pressure and mid level shortwave head offshore. Satellite
shows clearing not far behind so expect south coastal locations
to clear out later this afternoon, leaving clear skies across
SNE tonight. Combination of dry airmass and light N winds will
result in good radiational cooling. NBM isn`t too far off from
colder MOS guidance but expect some of the typical cold spots to
drop into upper teens tonight. This includes parts of upper cape
Cod and KMVY (in the middle of the island in pine barrens).

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Updated 1230 PM Wed

Key Messages:

* Dry weather and below normal temperatures.

High pressure remains over SNE Thu before heading to the
Maritimes Thu night resulting in some high cloudiness due to
fairly zonal flow aloft and weak warm advection. Temperatures
Thu should average a few degrees higher than today followed by
another cold night Thu night.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Updated 110 PM Wed

Key Messages:

* No impactful weather expected.

Details...

A northern stream shortwave trough tracks to the north of the region
late Fri into Sat. Weak warm advection and SW flow ahead of the
trough will bring in more seasonable temperatures with highs in the
upper 40s for the higher terrain and low 50s elsewhere.
Moisture/forcing are limited, but weak ascent will support scattered
showers later Fri. Some model solutions show a secondary low
developing offshore which in that case would bring a higher chance
for a period of steady rain across the south coast and SE MA (mainly
Cape/Islands). For timing, most model guidance has trended later
with the higher risk for showers Friday evening-early Saturday AM. A
few showers may linger across the Cape/Islands Saturday morning
depending on the the track of the secondary low. Overall, this is
likely to be a lower QPF event with ensembles showing a range from a
trace to 0.25" with the higher probabilities for seeing greater than
0.10" south of I-90.

A cold front will accompany the trough passage Sat. night, bringing
with cooler temperatures aloft slowly pushing in from NW to SE.
Timing of the cold is still a little uncertain among deterministic
guidance which will influence high temperatures. If it ends up
coming in earlier, highs would be cooler in the low to mid 40s,
upper 30s for the higher terrain. If slower, warm temps may hang in
there longer along the south coast/SE MA. High pressure will keep
conditions mainly dry Sat. Quasi-zonal flow for Sunday with a weak
embedded shortwave moving through the flow. However, moisture will
be limited favoring dry conditions. Ensembles favor quasi-zonal flow
Monday with weak mid-level ridging building in briefly Tues. There
is a signal for a frontal system to move through sometime later Tue
into Weds. Details are still uncertain this far out, but at this
point this is more likely favoring rain based on thermal profiles.
Temperatures next week will range close to normal next week in the
mid 40s to low 50s.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Forecaster Confidence Levels...

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

18z TAF Update: High confidence.

Theme remains the same with VFR conditions through Thu night.
W/NW winds 10kt or less veer to N later this afternoon and
persist through Thu, although winds should veer more to NE along
coast.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Friday through Monday/...

Friday: Mainly VFR, with local MVFR possible. Slight chance RA.

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

Saturday: VFR. Breezy. Slight chance RA.

Saturday Night through Sunday Night: VFR.

Monday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Updated 1230 PM Wed

High confidence through the weekend. No headlines anticipated.

High pressure maintains light N/NE winds through Thu.
Approaching cold front late Fri into Sat should bring some rain,
before another high builds into region over weekend.

Outlook /Friday through Monday/...

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

Friday Night: Winds less than 25 kt. Chance of rain.

Saturday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain.

Saturday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain.

Sunday: Winds less than 25 kt. Seas locally approaching 5 ft.

Sunday Night through Monday: Winds less than 25 kt.

&&

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

&&

$$

SYNOPSIS...JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...Mensch
AVIATION...JWD
MARINE...Mensch/JWD