Area Forecast Discussion
Issued by NWS Boston, MA

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919
FXUS61 KBOX 041501
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
1101 AM EDT Mon Aug 4 2025

.SYNOPSIS...
An extended stretch of dry weather with seasonable temperatures and
tolerable levels of humidity is anticipated for most of this week.
Our next chance for rain may not materialize until next Sunday.

&&

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

* Haze from Canadian wildfire smoke

* Dry with continued seasonable temperatures and slightly cooler
  temperatures on the immediate coasts from local sea breezes

Continued dry conditions as high pressure dominate our weather
pattern. Slightly above normal high temperatures with sea
breezes cooling the immediate coasts. Canadian wildfire smoke
will continue to move over southern New England, which may
have some concentration near the ground in spots.

&&

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

* Haze from Canadian wildfire smoke

Seasonable overnight conditions expected again tonight. Some
guidance indicates slightly higher relative humidity values
aloft overnight, which lines up with expected increasing cloud
cover heading into Tuesday morning. No rain expected. Some
wildfire smoke lingers tonight into Tuesday, but may not be as
noticeable with the increased clouds.

Expecting a bit of a cool-down Tuesday across the eastern half
of our region. A front sagging south towards southern New
England will lead to a synoptic easterly flow. Since this will
be off the ocean with water temperatures in the 60s, this will
lead to below normal high temperatures. Farther inland, high
temperatures should remain slightly above normal.

&&

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

* Other than low (<20%) chances at showers or t-storms Tue
  Night-Thu in/around the Berkshires, an extended stretch of
  dry weather with seasonable temperatures remains in the offing
  for the first week of August.

* Highs mid 80s with lows mid 50s to lower 60s, to go along
  with cooler seabreezes each day.

* Uncertainty increases for late this weekend / early next week
  due to possible subtropical development off the Carolina
  coast.

Details:

Overall, no substantial changes noted in today`s guidance versus
yesterday`s in terms of the forecast for much of this workweek
into the early weekend. We still anticipate an extended stretch
of dry weather with seasonable temperatures and low humidity
levels, driven by established high pressure near Nova Scotia.
There remains a slight-chance mention of diurnally-driven
showers/t-storms over the terrain areas in western/northwest MA
Wed thru Thu, but won`t be raining the whole time at these
locations. Other than that though, it`s a dry forecast through
at least Sat with highs in the mid 80s and lows mid 50s to
lower to mid 60s. Dewpoints in the mid 50s to lower 60s to boot
too, so humidity levels should be tolerable.

Uncertainty then increases into Sunday and early next week, as
the ridge in place weakens. Farther southward off the Carolina
coast, the NHC is monitoring a couple areas of disturbed
weather. One, Tropical Storm Dexter, is expected to pass well
to our southeast later this week, as it will be suppressed by
the strong Nova Scotia high pressure. Another area of disturbed
weather with lower chance at development (up to 30%) is north
of the Bahamas and southeast of the Carolina coast. This feature
is forecast to drift northwestward towards the Carolina coast
and then may recurve NE late in the weekend or early next week.
There are some GFS and GEM-based model solutions which bring
this system close enough to our southeast in which some effects
could be possible, but without a well- defined circulation
center, tough to have much confidence in any potential outcome
at this time. We`ll continue to monitor this area closely
through the workweek but as of now, it`s way too early to
pinpoint impacts, if there were to be any at all. For the latest
on the tropics, refer to the latest Tropical Weather Outlooks
issued by the NHC. If nothing else, it serves as a reminder that
we are in the midst of tropical cyclone season.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

15z Update...

Today...High confidence.

VFR/MVFR(Due to smoke). Light N to NW winds this morning,
before sea breezes develop once again. Haze from wildfire smoke
could cause some minor visibility impacts through this evening.

Tonight...High confidence.

VFR. SW winds shift more NE overnight but remain light.
Increased cloud cover heading into the morning hours, but
ceilings should remain firmly VFR.

Tuesday...High confidence.

VFR. E to NE winds at 10-15 knots. Minor visby reductions
possible due to smoke/haze.

KBOS terminal...High confidence in TAF.

VFR/MVFR(Due to smoke). Sea breeze kicks in around 16z today
and kicks out around 01z tonight. Expecting mild visby reduction
today due to near sfc smoke. Smoke concentrations decrease
slightly after 01z, but will linger through tomorrow.

KBDL terminal...High confidence in TAF.

VFR/MVFR(Due to smoke). Light N/NW winds today with near sfc
smoke and haze. Winds flip SSW tonight then to the NE towards
day break tomorrow.

Outlook /Tuesday Night through Friday/...

VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday...High confidence.

High pressure remains over the waters. A period of relatively
light winds and seas with good visibility continues.

Outlook /Tuesday Night through Friday/...

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

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert until midnight EDT tonight for MAZ002>024-
     026.
RI...Air Quality Alert until midnight EDT tonight for RIZ001>008.
MARINE...None.

&&

$$

SYNOPSIS...Belk/Loconto
NEAR TERM...Belk
SHORT TERM...Belk
LONG TERM...Loconto
AVIATION...McMinn/KP
MARINE...Belk/Loconto