361
FXUS61 KBOX 101044
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
644 AM EDT Sun Aug 10 2025

.SYNOPSIS...
High pressure off the coast will bring increasing heat and
humidity through mid week but it will not be as oppressive as it
was earlier in the summer. Temperatures should cool a bit
Thursday, along with scattered showers or thunderstorms as a
cold front moves through, then drier weather follows next
weekend.

&&

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

* Turning warmer today with some 90 degree readings inland

High pressure becomes centered offshore as upper ridging builds
over region. Plenty of sunshine will combine with warming aloft
to help highs reach 90 degrees in a few inland spots. Gradient
remains weak enough to allow for sea breezes along both coasts,
so it will stay a little cooler there. It will be a little more
humid than past few days but not too noticeable with dewpoints
in lower 60s. Tonight will feature clear skies once again with
patchy fog in valleys and near Cape Cod/Islands.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
Key Messages:

* Increasing heat and humidity but probably just shy of Heat
  Advisory criteria

Upper ridge continues to dominate as increasing SW flow brings
more humid air into region, but not as oppressive as what we
experienced earlier in summer. Additionally, gradient remains
weak enough to allow for sea breezes along both coasts Mon and
probably Tue as well. Combination of highs in low to mid 90s
inland and dewpoints climbing into mid 60s will yield heat index
close to 95 degrees, especially Tue, but it still looks marginal
at this point in parts of CT and Merrimack Valleys as well as
northern RI and interior eastern MA.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Key Messages:

* Peak of heat and humidity Wed.

* Heat may last into Thu before PM clouds/possible storms.

* Cooler Fri and into weekend.

Heat and humidity should peak Wed with broad SW flow. Still
looks marginal for Heat Advisory criteria with highs inland
reaching 90-95 and dewpoints into mid 60s, and favored areas
continuing to be parts of CT and Merrimack Valleys into northern
RI and eastern MA. It`s also possible that cloudiness works
into SNE Wed afternoon, limiting heating before scattered
thunderstorms arrive later in day.

Upper ridge gets suppressed Thu as short wave moves through
Great Lakes. This should bring cold front through region,
accompanied by showers and storms, although coverage may be more
hit and miss, before cooler and drier weather follows Fri and
into weekend.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

12z TAF Update: High confidence.

VFR, aside from local MVFR/IFR vsbys possible due to patchy fog
across interior valleys and near Cape Cod and Islands late
tonight. Light S/SW winds expected with sea breezes along both
coasts today and Mon.

KBOS terminal...High confidence in TAF.

KBDL terminal...High confidence in TAF.

Outlook /Tuesday Night through Thursday/...

Tuesday Night: VFR.

Wednesday: VFR. Breezy.

Wednesday Night: VFR. Breezy. Slight chance SHRA, slight chance
TSRA.

Thursday: VFR. Slight chance SHRA, slight chance TSRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

High confidence through the end of the week.

Weak gradient will allow for sea breezes near shore today
through Tue, before high pressure offshore brings SW flow
much of week. Winds and seas should remain below SCA levels.
Patchy fog may limit visibility later at night and early in
morning.

Outlook /Tuesday Night through Thursday/...

Tuesday Night through Wednesday: Winds less than 25 kt.

Wednesday Night through Thursday: Winds less than 25 kt. Slight
chance of rain showers.

&&

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

&&

$$

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