Area Forecast Discussion
Issued by NWS Boston, MA
Issued by NWS Boston, MA
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FXUS61 KBOX 262031
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
331 PM EST Wed Nov 26 2025
.SYNOPSIS...
A cold front sweeps across the region late tonight. Colder and
windier conditions follow behind the front for Thanksgiving.
Colder temperatures with windy conditions Friday and Saturday,
with scattered flurries at times in interior Southern New
England. Another low pressure passes to our north and west
Sunday afternoon and night bringing a period of rain. Cooling
down again for Monday as a cold front passes through. Monitoring
possible storminess around the middle of next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Key Messages...
* Cold front moves through overnight with breezy westerly winds and
clearing skies behind it.
Details...
Mainly cloudy with some breaks of sun for the remainder of the
afternoon with a few showers for the Cape/Islands. Can`t rule out a
brief sprinkle elsewhere. Overnight, a cold front will sweep across
southern New England quickly clearing out the lower clouds. High-
resolution guidance shows some light rain showers possible
accompanying the front, mainly across western southern New England.
Gusts 20-30 mph are possible as cold air advects into the
region.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Key Messages:
* Colder and blustery for Thanksgiving.
Details...
Southern New England will be in a cool post-frontal airmass
Thursday. 850mb temperatures drop to -4 to -6C yielding high
temperatures in the low to mid 40s, about 10-15 degrees cooler than
Wednesday. Evident in model soundings, the cold advection and
westerly flow will allow for a sufficient mixing in the boundary
layer. This will lead to a fairly blustery day with gusts 25-35 mph.
Mainly clear skies Thursday night which will support optimal
radiational cooling within the cool airmass. This should allow
temperatures to drop into the mid to upper 20s for inland areas and
low 30s for coastal areas.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Key Messages:
* Windy Fri and Sat (gusts Fri 35-45 mph) with below normal temps.
Scattered flurries for interior sections possible Fri.
* Low pressure brings rain later Sunday into Sunday night.
* Cooldown later Monday; possible storminess Tue-Wed?
Details:
Friday and Saturday:
Cold cyclonic flow regime takes hold of Southern New England for the
post-Thanksgiving Day period, as deep upper troughing moves through.
Gusty WNW winds particularly for Fri will accompany the period of
cooler than normal temps, given a tight pressure gradient and a deep
but well-mixed boundary layer allowing for efficient daytime
momentum transport. Gusts Fri probably fall just short of Advisory
level at around 30-40 mph (perhaps in the 45 mph range around the
interior higher terrain); but the main impact will be mostly colder
wind chills for post-holiday shoppers/those outdoors. Highs in the
mid 30s to lower 40s but will feel like the mid 20s to around 30
with the westerly winds. With some Great Lakes-enhanced moisture on
the stronger westerly flow, it`s more of a partly to mostly cloudy
look, and with enough moisture and some modest lift in the snow-
dendrite growth temperature layer, could be some flurries/flakes
whipped around by the stronger winds in the interior but nil
impact/accum. Sustained westerly winds during the night will keep
temps from falling very far but it will still feel quite chilly.
Sat also stands to feature below normal temps and blustery winds,
but lower gusts (25-30 mph) to go along with more sun should take
the edge off the colder apparent temps for those with weekend plans.
Sunday:
High pressure to our south early on Sunday moves offshore as the
next area of low pressure treks from MI east-northeast through the
St. Lawrence River for Sunday afternoon and night per model
consensus. With increased southerly flow, this is ordinarily a
warmer (e.g. liquid/rainier) storm track, with rains breaking out
Sunday afternoon and should remain as rain for the majority of the
time, before ending as a brief period of snowflakes for the
interior/higher terrain. Wetting rains look likely but significant
rains are not anticipated.
Early Next Week:
Drier weather with a gradual cooldown in temps toward below normal
levels for Monday, especially later in the day into the night. We`ll
then have to monitor larger-scale developments toward Tue and/or Wed
as shortwave trough energy moves through the southern/south-central
tier of states and could allow for low pressure to trek over or
south of Southern New England. The timing, the exact track and the
northward extent of precipitation, each of which are still uncertain
at this early juncture; some wintry weather accumulations would be
possible if a favorable storm track materializes. Initial look
favors more of a plain rain/interior snow-rain mix. Water temps
which are still in the upper 40s/lower 50s, so as is often the case
with early and late-season wintry events, any sustained onshore flow
given these water temps would force more rain into the picture vs
what model precip types would otherwise show. We`ll continue to
monitor this potential over the coming days.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
18Z update...
This Afternoon...High confidence in trends, moderate in timing
Mainly MVFR-IFR conditions for remainder of afternoon. LIFR for
Cape/Islands. Low probability/low confidence for LIFR late
afternoon-early evening for PVD/BOS. Included as a FEW005 in TAF
due to low confidence. Few -SHRA through the evening for
Cape/Islands. BR/FG for Cape/Islands bringing down vsbys to
1/2SM to 2SM. As low as 1/4 (mainly ACK). Winds SSW/SW at 9-15
kts.
Tonight...High Confidence
Cold frontal passage between 02-08Z from west to east, with
ceilings/vsbys rapidly improving to VFR behind it. Winds shift
to W/WSW with front passage sustained 10-15 kts with gusts 20-25
kts, especially with/just behind the front passage.
Thursday/Thanksgiving...High Confidence.
VFR. Brief period of lighter WSW winds 12-14z before winds mix
back down by 15Z, then W winds 10-15 kts with gusts 20-30 kts
through remainder of day.
KBOS Terminal...Moderate confidence in TAF.
MVFR dropping toward IFR after 20Z. Low probability for LIFR
cigs and BR in the evening briefly. Too low of confidence to
mention in TAF, but did include a FEW005 after 23z to hint at
the potential. FROPA timing 04-06Z overnight with cigs clearing
to VFR by 08Z. Windshift to W with gusts 20-25 kts.
KBDL Terminal...High confidence in TAF.
Outlook /Friday through Monday/...
Friday: VFR. Windy with gusts up to 35 kt. Scattered SHSN.
Friday Night: VFR. Windy with gusts up to 35 kt.
Saturday: VFR. Breezy.
Saturday Night: VFR.
Sunday: Mainly VFR, with local MVFR possible. Breezy. Chance
RA.
Sunday Night: Mainly VFR, with local IFR possible. Windy with
local gusts up to 30 kt. Chance RA.
Monday: Slight chance RA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Today through Thanksgiving... High confidence.
* Small Craft Advisories for all marine zones Thursday.
* Gale Watch for Friday through early Saturday across all
waters.
Localized dense fog possible this evening over the cooler ocean
waters. A cold front crosses the waters after midnight clearing
fog/low clouds. Gusts 25-34 kts are possible for a period after
the frontal passage early Thursday morning.. Otherwise
winds/gusts 20-30 kts for marine zones tomorrow. Seas rising to
6-8ft by the afternoon for the southern outer waters. This will
keep marine zones in SCA criteria all day tomorrow. Southern
outer waters may briefly by shy of gale winds for a brief period
with the frontal passage early tomorrow morning. Gale Watch is
in effect for Friday where confidence is increasing for Gale-
force winds on Friday.
Outlook /Friday through Monday/...
Friday: Moderate risk for gale force winds with gusts up to
40 kt. Rough seas up to 13 ft.
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 30 kt. Seas locally approaching 5 ft. Chance of rain.
Sunday Night: Moderate risk for Small Craft Advisory winds with
areas of gusts up to 30 kt. Local rough seas. Rain likely.
Monday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 4 AM Thursday to 6 AM EST Friday for
ANZ230-231-236-250-251-254.
Gale Watch from Friday morning through Friday evening for
ANZ230-236.
Gale Watch from Friday morning through Saturday morning for
ANZ231>235-237-250-251-254>256.
Small Craft Advisory until 6 AM EST Friday for ANZ232>235-237-
255-256.
&&
$$
SYNOPSIS...Loconto/Mensch
NEAR TERM...Mensch
SHORT TERM...Mensch
LONG TERM...Loconto
AVIATION...Loconto/Mensch
MARINE...Loconto/Mensch