Area Forecast Discussion
Issued by NWS Boston, MA

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960
FXUS61 KBOX 301141
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
741 AM EDT Sat Aug 30 2025

.SYNOPSIS...
An extended stretch of dry and early fall like weather will
prevail through much of next week as high pressure remains over
the Northeast. Our next chance for rain may not materialize
until around Thursday or Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
230 AM Update:

Key Message:

* Mostly sunny, dry and seasonable. Temps in the 70s.

Details:

Cold front is just pulling offshore, trailing just west of
Chatham and into Nantucket Sound. As of this issuance, there are
still some heavier showers and a few thunderstorms in Nantucket
Sound but those will be pulling away in short order. Otherwise,
cool and dry advection is taking hold of Southern New England,
as sfc ridging from a broad 1022 mb high pressure over the UP of
MI was building in. The other synoptic feature of interest is a
closed upper low and its associated cold pocket of air aloft
pinwheeling around north of Montreal per WV imagery. These two
large-scale features will continue to drive our weather for
today and really through the rest of the Labor Day Weekend.

From a weather perspective, it`s a picture-perfect, chamber-of-
commerce Saturday in store for Southern New England, with mostly
sunny skies, temps slightly cooler than normal and a modest
refreshing northwest breeze. We look to mix pretty deep today with
dewpoints crashing into the 40s. There may be some fair weather
cumulus streets over northern MA closer to the cold pool aloft but
really of no consequence with more Cumulus coverage and related
possible showers confined to VT/NH. Highs upper 60s/low 70s for the
terrain, and mid 70s elsewhere. Get out and enjoy it!

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
230 AM Update:

Key Messages:

* Clear, calm and cool Sat and Sun nights, with patchy fog in the
  river valleys.

* A little milder Sunday but still seasonable, although with
  seabreezes/modest onshore winds. Highs mid t o upper 70s, low
  70s eastern coast.

Details:

Tonight Through Sunday Night:

The upper level low pressure begins to open up and move ESE
from northern VT/NH into ME by Sunday morning, then into Nova
Scotia by Sunday. Meanwhile surface ridging will continue to
rule, supporting continued dry and seasonable weather.

Clear, cool and dry tonight with expected strong radiational
cooling. Only real question mark is on if we can get patchy fog
to develop during the overnight; NW winds may be just high
enough to preclude its formation until sunrise. River valleys
and around the I-495 corridor in the usual spots (Norwood,
Bedford, Taunton etc) stand the best chance of development.
Lows in the mid 40s to low 50s, with mid 50s east coast of MA.

Dry weather then continues into Sunday with seasonable
temperatures. Not quite a repeat of today, as we`ll see cooling
seabreezes develop as winds turn ENE. Warming 925 mb temps
should support highs in the mid to upper 70s but in the lower
70s along the eastern coast of MA. Clear and dry weather again
the case for Sunday night too, with potential for patchy river
valley fog under good radiational cooling. Lows upper 40s to the
middle 50s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
230 AM Update:

Key Messages:

* Dry, seasonable temps with seabreezes through at least Thurs.
* Next chance for rain around Thurs/Fri.

Details:

Still under broad troughing in the mean through much of the
upcoming workweek, but sprawling high pressure over Nova Scotia
will maintain at least a modest onshore flow; other than some
hit or miss (mostly miss) showers around the higher terrain
around Tue, we look dry through at least late in the week.
Followed the pretty strong agreement amongst the global
models/ensembles vs the NAM in this timeframe, as the NAM looks
like quite an outlier with its depiction of a coastal low moving
up the northeast coast on Tue and has no support from the
globals. Expect dry weather, seasonable temps (highs in the 70s,
upper 70s/near 80 CT Valley) and several days of onshore
flow/seabreezes.

Our next chance for rain doesn`t look to appear until late in
the week; though there`s the usual uncertainty with the details
at this range, early indications continue to suggest a decent
rain event.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...

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

12z TAF Update: High confidence in trends.

Through Sunday Night...High Confidence.

VFR ceilings/visbys through Sunday night. Only exception is with
patchy fog at BAF, BED and perhaps BDL during the overnight to
pre-dawn hrs tonight into early Sunday morning.

W/NW winds around 5-10 kt today, with occasional gusts under 20
kt. Light winds tonight.

Light northeast winds on Sunday, seabreezes along the eastern
coast around 14-15z, which become light north Sunday evening.

KBOS TAF...High confidence in TAF. VFR, W/NW winds around 10 kt,
may become WSW around 20-22z before returning to W/NW.

KBDL TAF...High confidence in TAF.

Outlook /Monday through Wednesday/...

Sunday Night through Tuesday Night: VFR.

Wednesday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Updated 230 AM Fri: High confidence.

Winds and seas below SCA criterion today right on through at
least midweek. W winds 5-10 kt today, which become N/NE at
similar speeds Sun. Seas 4 ft or less all waters. May see some
increase in seas on outer south coastal waters as we approach
the middle of next week.

Outlook /Monday through Wednesday/...

Sunday Night through Monday Night: Winds less than 25 kt.

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

Tuesday Night through Wednesday: Winds less than 25 kt. Areas
of seas approaching 5 ft.

&&

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

&&

$$

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