357
FXUS61 KBOX 051818
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
218 PM EDT Sun Oct 5 2025

.SYNOPSIS...

A ridge of high pressure in control of our weather will continue to
bring dry and unseasonably warm afternoon temperatures through
Tuesday. A cold front moves through Southern New England Tuesday
night into Wednesday, bringing much needed rainfall. Much cooler
temperatures follow Thursday and Friday with dry weather as
well.

&&

.NEAR TERM /THROUGH TONIGHT/...

Key Messages...

* Dry/tranquil tonight...lows upper 40s & 50s but 60-65 in BOS/ORH
* Patchy fog late in the typical spots & near the south coast

Details...

Tonight...

A ridge of high pressure to our south will continue our dry weather
with above normal temperatures tonight. Clear skies will still
result in overnight lows dropping into the upper 40s in the
normally coolest outlying locations...to mainly the 50s elsewhere.
Meanwhile...the Urban Heat Island of Boston as well as Worcester
will only see low temps drop into the 60-65 degree range.

Calm/light southwest winds will result in patchy fog developing late
in the typically prone locations. We may also see some patchy fog
near the south coast, Cape and Islands with higher dewpoints.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...

Key Messages...

* Sunny with near record highs Mon in the lower to middle 80s
* Dry with patchy fog Mon night...lows mainly in the 50s

Details...

Monday...

Upper level ridge of high pressure centered to our south will
continue result in well above normal height fields being pumped into
southern New England on Monday. 850T around +14C/+15C along with
plenty of sunshine will result in near record high temperatures.
Highs Mon will top out in the lower to middle 80s in most locations
away from the immediate south coast, Cape and Islands. Southwest
winds should be strong enough to prevent sea breezes along the
eastern MA coast...so modified marine cooling will be confined to
mainly south coast, Cape and Islands where highs should generally be
in the 75 to 80 degree range.

Monday night...

A ridge of high pressure to our southeast will continue our dry and
unseasonably mild weather Monday night. Low temps Monday night
should be mainly in the 50s...but lower 60s expected in the Urban
Heat Island of Boston. A few of the normally coolest outlying
locations may drop to around 50. Another round of patchy fog
expected late in the typically locations and also towards the south
coast.


&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...

Key Messages:

 * Unseasonably warm conditions continue on Tuesday

 * Cold front brings rain, gusty winds, and crashing temperatures on
   Wednesday

 * More fall-like weather Thursday and Friday.

Warm and windy conditions on Tuesday as strong SW flow kicks in
ahead of Wednesdays cold front.  High temperatures jump to the upper
70s to low 80s one last time before fall returns.  Increasing
southwesterly winds aloft will lead to gusty winds at the surface,
with gusts of 20-30mph in the afternoon.  With the deep
southwesterly flow, dewpoints will rise into the upper 50s to low
60s.  The high dewpoints will keep warm conditions around overnight
on Tuesday, with lows only dropping to the mid-to-upper 50s.

A strong upper-level shortwave arrives early Wednesday morning, with
the trailing cold front moving through by midday.  Guidance has come
into better agreement with QPF, showing a widespread half inch
across the region, with upwards of 1.0-1.5 inches near the south
coast and Islands where better moisture and instability reside.
There could be a rumble or two of thunder with the passage of the
cold front, but not anticipating any severe weather, as instability
will generally be under 200 J/kg.  High temperatures on Wednesday
are expected to be much closer to seasonal values thanks to the cold
front, with readings in the 60s.  It will still be breezy on
Wednesday with continued gusts of 20-30mph, higher over the waters.

High pressure drops out of Canada on Thursday, bringing a return to
sunny skies, but high temperatures will only reach the upper 50s to
low 60s with the cold airmass in place.  Winds gradually diminish
through the day on Thursday, remaining out of the north.  With clear
skies and light winds overnight Thursday, Friday morning will likely
be the coldest morning we`ve had so far this fall, with lows
dropping into the upper 20s to low 30s. High temperatures on
Friday rebound into the mid-60s as the wind becomes light
southwesterly again.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

18z TAF Update...

Tonight through Monday night...High confidence.

VFR conditions persists right through Monday night. The exception
will be late night/early morning patchy ground fog in the typically
prone locations as well as areas near the south coast. Calm/light
SSW winds tonight becoming SW at 5 to 15 knots on Monday.

KBOS Terminal...High confidence in TAF. Sea breezes kick out by
23z/00z this evening. SW gradient should be strong enough to prevent
sea breezes on Monday.

KBDL Terminal...High confidence in TAF.

VFR. Light southerly winds

Outlook /Tuesday through Thursday/...

Monday Night: VFR. Breezy. Patchy BR.

Tuesday: VFR. Breezy.

Tuesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance SHRA.

Wednesday: MVFR/IFR conditions possible. Breezy. SHRA, slight
chance TSRA.

Wednesday Night: VFR. Breezy. Slight chance SHRA.

Thursday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Tonight through Monday night...High confidence.

Upper level ridge of high pressure centered to our south will
continue to keep the pressure gradient weak enough so that
conditions remain below small craft advisory through Monday night.
SSW winds may gust between 15 and 20 knots at times later tonight
through Monday night...but again conditions should remain below
small craft advisory thresholds. There will be some concern for
overnight/early morning fog patches especially across the southern
waters.

Outlook /Tuesday through Thursday/...

Monday Night: Winds less than 25 kt. Patchy fog. Local
visibility 1 to 3 nm.

Tuesday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt.

Tuesday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft. Chance of
rain showers.

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft. Rain showers, slight chance of thunderstorms. Areas of
visibility 1 to 3 nm.

Wednesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 25 kt. Areas of seas approaching 5 ft. Chance
of rain showers.

Thursday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas up to 5 ft.

&&

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

&&

$$

SYNOPSIS...Frank/KP
NEAR TERM...Frank
SHORT TERM...Frank
LONG TERM...KP
AVIATION...Frank/KP
MARINE...Frank/KP