395
FXUS61 KBOX 072356
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
756 PM EDT Tue Oct 7 2025

.SYNOPSIS...

Cold front approaches the region tonight into Wednesday, bringing
much needed rainfall. Much cooler temperatures follow Thursday and
Friday with dry weather as well. Monitoring a possible coastal storm
early next week, but it remains uncertain if it will track far
enough north to bring us some rain and gusty winds.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...

Key Messages:

* Rain arrives after midnight as a cold front moves into the
  region. Periods of light to moderate rain expected into the
  Wednesday morning commute.

A cold front arrives late-tonight and exits east of the coastal
waters Wednesday, in fact, first-half of tonight remains dry.
Rain overspreads from west to east, entering western areas of
southern New England roughly on either side of midnight and
getting to the Boston to Providence corridor by 5 AM to 7 AM.
Cold front is interacting with sufficient moisture, PWATs are
roughly ~1.6" which is two standard deviations above normal.
Cannot rule out a rumble or two of thunder either with limited
instability, leading to pockets of heavier rain. Much needed
rainfall amounts between 0.5" and 1.0" for most of the region,
though an area of higher amounts of 1.0" to 2.0" cannot be ruled
out within areas of convection. HREF showed a strip of these
higher totals from southeast CT, southern RI, and southeast MA
with totals up to 1.5". While not out of the question but still
a low probability, is the chance of 2+ inches across RI and
southeast MA, based off the HREF ensemble LPMM.

Don`t anticipate any flash flooding, although common poor drainage
areas could see large puddles, especially leaf litter starting to
collect with fall underway. Not ideal for the morning commute, do
take your time heading out the door.

With the added cloud cover tonight and southerly flow it will remain
mild with lows in the upper-50s and lower-60s.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...

Key Messages:

* Cold front exits with showers ending by late morning west and
  early afternoon east. Clearing overnight with chilly temperatures.

The mid-level trough pushes the surface cold front out to sea and
will have improving conditions starting late morning across CT River
Valley. These conditions gradually improve to the east, reaching the
I-95 corridor by early afternoon, and finally clearing the Cape and
Islands mid afternoon. Temperatures are noticeably cooler
behind the front, in fact, many daytime highs likely occur
during the morning hours. Early afternoon temperatures are only
in the low-60s and with a breezy north-northwest wind, Brrr!

Overnight, a 1035mb high build across the northern Great Lakes with
clearing skies and north-northwesterly flow. Will be chilly, lows
fall into the low-40s and upper-30s. Would not be surprised if a few
of our high elevation communities in northwestern MA (AOA 1,500 ft)
dip down to the freezing mark.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...

Key Messages...

* Dry/much cooler Thu/Fri...highs in the middle 50s to the lower
  60s...lows Thu night in the 20s/30s with frost/freeze conditions

* Remaining dry Sat with highs moderating into the middle-upper 60s

* Potential for a Hybrid coastal storm to bring some rain/gusty
  winds early next week...but may remain south keeping us dry

Details...

Thursday and Friday...

A large 1035 mb high pressure system builds in from the Great Lakes
Thu into Fri. This will bring in much cooler/below normal
temperatures to the region. Despite plenty of sunshine Thu...850T
dropping to between -2C and -4C will hold Thu high temps to between
55 and 60 in most locations!. NNW winds will gust to between 20 and
25 mph...so a taste of fall is on tap for the region.

High pressure builds overhead Thu night setting the stage for an
excellent night of radiational cooling. Given the dry/cool airmass
overhead...thinking overnight low temps will mainly be in the 20s
and 30s. This will result in our first fairly widespread
frost/freeze conditions across southern New England. Plenty of
sunshine follows for Fri and as mid level temps moderate a
tad...expect highs to recover into the lower 60s. Much lighter winds
on Fri compared to Thu...so it will feel milder by Fri afternoon.

Saturday...

Upper trough shifts east of the region along with high pressure at
the surface...but it will remain dry. This allows a return flow
of milder air to work in from the southwest. Highs should
recover Sat into the middle to upper 60s.

Sunday through Tuesday...

The forecast remains quite uncertain early next week. We will be
watching a potential Hybrid coastal storm off the mid-
Atlantic/southeast coast. There is considerable spread on the models
and their ensembles on whether or not this system will get far
enough north to bring some rain/gusty sometime Sunday through
Tuesday or stays south and we remain dry. We still need a few more
days until we have a better idea. For what its worth...the one thing
we noticed was that the EPS tended to be more suppressed compared to
the EPS AI version...which brings the rain significantly further
north into our region. We should also mention that if the storm does
come far enough north...there will be a minor coastal flooding risk
as we will just be coming off King Tides.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...

Forecaster Confidence Levels...

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

00z TAF Update...

Tonight and Wednesday...Moderate confidence.

VFR conditions much of the night but southwest LLWS will be an
issue with a modest low level jet. Rain arrives from northwest
to southeast in the 06z to 14z time frame bringing low end
MVFR-IFR conditions with it. Moderate to briefly heavy rain
expected with even the low risk for a rumble of thunder. The
back edge of the rain will clear much of the interior by
lunchtime, the coastal plain by mid afternoon and the
Cape/Islands by late afternoon/early evening. As this
happens...conditions should gradually improve to higher end MVFR
and then VFR levels from NW to SE. Southwest wind 10 to 15
knots with gusts of 20-25 knots tonight will shift to the
northwest at the same speeds on Wednesday behind the cold front.

Wednesday Night: VFR. NW wind gust to between 15 and 20 knots
with gusts of 20 to 30 knots toward the Cape and Nantucket.

KBOS Terminal...Moderate confidence in TAF.

KBDL Terminal...Moderate confidence in TAF.

Outlook /Thursday through Sunday/...

Thursday: VFR. Windy with local gusts up to 30 kt.

Thursday Night: VFR. Breezy. Areas frost.

Friday through Saturday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Tonight through Wednesday Night...High confidence.

Southwest wind and gusts are increasing ahead of an approaching cold
front, which will swing across the waters on Wednesday. Gusts of 20
to 30 knots are expected and seas 3 to 5 feet. Have expanded
the Small Craft Advisory to all waters, with the exception of
Narragansett Bay. Moderate rain on Wednesday will also result in
lower visibilities. Winds shift to the NW Wednesday with gusts
between 20 and 30 knots and may even see a few gusts around 35
knots Wednesday night in the strong cool advection pattern.
Small craft headlines will continue.

Outlook /Thursday through Sunday/...

Thursday: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Local rough seas.

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

Friday through Saturday: Winds less than 25 kt.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 5 PM EDT Thursday for ANZ230>235-
     237-250-251-254>256.

&&

$$

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