440
FXUS61 KBOX 312306
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
706 PM EDT Thu Jul 31 2025

.SYNOPSIS...
Much cooler conditions are expected into Friday, with the
potential for heavy rain and localized flooding tonight across
portions of interior southern New England. An extended stretch
of dry weather then develops for this weekend into early next
week. Temperatures are seasonable with lower humidity levels
this weekend, but with a warming trend for early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
Key Messages:

* Showers with local downpours will begin to shift southward
  tonight.
* Heaviest rainfall axis expected to be across interior MA into CT
  where localized amounts up to 3-4 inches possible

Updated 705 PM

Main axis of rainfall associated with 850 mb front and favorable
coupled jets has become more stratiform in nature this evening
and rainfall rates have decreased over past few hours. This axis
will shift southward tonight, bringing much needed rainfall to
SNE but not expecting any flooding issues aside from typical
poor drainage areas. That said, environment over CT and points
S/W is still somewhat favorable for flooding rainfall, though
chances have decreased since the afternoon, but in collaboration
with WPC and neighboring offices we will keep the Flood Watch
posted tonight in CT. Most areas should pick up 1-2" by Fri
morning with localized amounts up to 3-4 inches from central/W
MA into NW CT.

&&

.SHORT TERM /FRIDAY NIGHT/...
Key Messages:

* Showers end during the morning near the south coast with sunshine
  developing from NW to SE during the afternoon. Below normal temps.

* Clearing and chilly Fri night with lows in the 50s

Drier air will be moving southward into SNE by Fri morning with
PWATs falling through the day. Rain will have ended across much of
the interior by morning, with showers lingering near the south
coast. However, expect rain to end here through the morning with
mainly dry conditions in the afternoon. Modest low level jet will
result in gusty NE winds, especially near the coast. The wind and
rain here in the morning with temps in the 60s will make it feel on
the raw side.

Drier air will continue to move southward into the region which will
allow sunshine to develop from NW to SE during the afternoon. Highs
will recover into the low-mid 70s in the interior, but closer to 70
across RI and SE MA where sunshine will be later arriving.

Clearing skies Fri night as high pres builds in from the west, but
still enough gradient for a modest N breeze near the coast. Chilly
night with lows ranging through the 50s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Key Messages:

* Several days of dry and seasonable weather starting this
  weekend.

Upper flow should feature broad trough over Northeast starting over
the weekend and into much of next week, which will allow for a dry
and seasonable weather pattern to prevail. We start to see more
uncertainty toward the end of the week, when subtropical ridge
should build off southeast coast and dig deeper trough over
eastern Great Lakes and Ohio Valley. While we don`t see return
of hot and humid conditions, it may promote moisture feed up
East Coast and could bring our next round of rainfall,
especially if we see surface low development near mid Atlantic
coast.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels...

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

00z TAFs: High confidence.

Broad area of showers with IFR will shift southward tonight.
Showers should end Fri morning with improvement to MVFR, then to
VFR Fri afternoon/night as skies eventually clear.

N/NE winds expected, with 20-25kt gusts mainly near coast
tonight.

KBOS terminal...High confidence in TAF.

KBDL terminal...High confidence in TAF.

Outlook /Saturday through Tuesday/...

Saturday: VFR. Breezy.

Saturday Night: VFR.

Sunday through Sunday Night: VFR. Breezy.

Monday through Tuesday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Friday night...High confidence.

Increasing NE winds developing tonight into Fri with gusts to 30 kt
as low level jet develops. Gusty winds will slowly subside across NE
MA waters later in the day, but this will take until late Fri night
over southern waters.

Outlook /Saturday through Tuesday/...

Saturday: Winds less than 25 kt. Areas of seas approaching
5 ft.

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

Sunday through Tuesday: Winds less than 25 kt.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch through Friday morning for CTZ002>004.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 2 AM EDT Saturday for ANZ231>235-
     237.
     Small Craft Advisory from 2 AM to 8 PM EDT Friday for ANZ236-
     251.
     Small Craft Advisory until 8 AM EDT Saturday for ANZ250-
     254>256.

&&

$$

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