Area Forecast Discussion
Issued by NWS Boston, MA

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252
FXUS61 KBOX 251123
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
723 AM EDT Tue Aug 25 2026

.WHAT HAS CHANGED...
Small Craft Advisory canceled.

&&

.KEY MESSAGES...

- Mainly dry and seasonable conditions, outside of a stray
  shower this afternoon across the western half of southern New
  England.

- Main risk for a round of scattered showers and a few
  thunderstorms will be sometime late Thu/Thu night into Fri
  with summerlike humidity. Mainly dry and seasonable weather
  favored for this weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...Mainly dry and seasonable conditions, outside of
a stray shower this afternoon across the western half of
southern New England.

Southern New England will be stuck between a couple of synoptic
features, leaving our weather somewhere in the middle as well.
High pressure over the OH Valley and central Appalachians should
mean plenty of dry hours today with a steady west to southwest
wind. However, the subsidence from this high pressure will not
be absolute.

A mid level cold pool over the Great Lakes and Ontario should
generate some diurnal clouds heading into this afternoon, which
will then diminish with sunset. The addition of a weak surface
trough moving into southern New England could trigger a few
showers this afternoon. Anticipating most unstable CAPE values
between 500-750 J/kg this afternoon. Thus, cannot completely
dismiss the idea for a thunderstorm or two. However, severe
weather is not expected. The greatest risk for these showers
will be across the western half of southern New England, away
from the marine influence.

Dry weather is expected Wednesday.

As for temperatures, expect a seasonable week, with afternoon
highs in the lower 80s and higher-terrain communities in the
northern Worcester Hills and eastern Berkshires remaining in the
middle to upper 70s. Nightly lows will be a touch cooler as
clear skies and light winds allow for radiational cooling, with
temperatures slipping back into the 50s while urban areas remain
near 60 degrees. This setup may allow for another night of low
stratus or fog. Confidence in how widespread it becomes remains
low; however, it does not appear this round of fog will be as
prevalent as last night.

KEY MESSAGE 2...Main risk for a round of scattered showers and a
few thunderstorms will be sometime late Thu/Thu night into Fri
with summerlike humidity. Mainly dry and seasonable weather
favored for this weekend.

The next shortwave trough approaches from the west by late in
the work week. Ahead of this approaching shortwave, summer-like
humidity will return Thu into Fri. Timing quite uncertain this
far out in the forecast. But appears there will be the potential
for a round of scattered showers and a few thunderstorms
sometime in the late Thu/Thu night into Fri time frame. CSU
machine learning probs do indicate some low probs for severe
weather/heavy rainfall potential. But that is really just climo
for an approaching shortwave this time of year. So, not much
more we can say at this point. Current guidance does indicate
that drier/seasonable weather is favored to return for this
upcoming weekend.

&&

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

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

Today...High confidence.

VFR, outside a few spot showers during this afternoon. W winds
6-12 knots, except some 20+ knot gusts possible this afternoon
towards the upper Cape.

Tonight...High confidence.

VFR. Calm/Light WNW winds.

Wednesday...High confidence.

Light west winds, with local seabreezes towards the coast.

KBOS Terminal...High confidence in TAF.

We think pressure gradient remains just strong enough to result
in mainly W winds today. However, the low probability exists for
a few hours of sea breeze. This risk/duration too limited to
insert into the TAF at this time.

KBDL Terminal...High confidence in TAF.

Outlook /Wednesday Night through Saturday/...

Wednesday Night: VFR.

Thursday: Mainly VFR, with local MVFR possible. Breezy. Chance
SHRA, slight chance TSRA.

Thursday Night: Mainly VFR, with local IFR possible. Chance
SHRA, slight chance TSRA.

Friday: VFR. Chance SHRA, chance TSRA.

Friday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.

Saturday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Wednesday...High confidence.

Fairly quiet boating conditions through the first half of this
week as high pressure develops across the Midwest before
expanding toward the waters off the coast of southern New
England. Gusty southwest flow develops today, with gusts around
20 kt. Conditions improve overnight into early Wednesday
morning as winds shift to the northwest.

Outlook /Wednesday Night through Saturday/...

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

Thursday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Chance of rain showers, slight chance of
thunderstorms.

Friday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers, slight chance of thunderstorms.

Friday Night: Winds less than 25 kt. Seas up to 5 ft. Slight
chance of rain showers.

Saturday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.

&&

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

&&

$$

DISCUSSION...Belk/Frank
AVIATION...Belk/Frank/Dooley
MARINE...Belk/Frank