Area Forecast Discussion
Issued by NWS Boston, MA

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830
FXUS61 KBOX 231121
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
721 AM EDT Thu Jul 23 2026

.WHAT HAS CHANGED...
No significant changes to the forecast.

&&

.KEY MESSAGES...

- Mainly dry with seasonable temperatures through the
  weekend.

- Unsettled weather for early to mid-week next week with
  periodic chances for scattered showers and thunderstorms.

&&

.DISCUSSION...
KEY MESSAGE 1...Mainly dry with seasonable temperatures through the
weekend.

A few showers and embedded weak storms are possible over our
coastal waters early this morning as the cold front pushes
offshore. By sunrise, the front should be fully through pushing
out any remaining showers. Weak mid-level troughing will persist
with drier and cooler conditions in the post-frontal airmass.
925 mb temperatures drop a few degrees from yesterday yielding
cooler high temperatures in the upper 70s to near 80 for
southern New England today. The airmass will be noticeable drier
as well bringing more comfortable humidity levels as surface
high pressure builds in from the west. This will also keep winds
on the lighter side with light NW winds and local sea breezes
for the coastal areas.

Surface high pressure builds further over the region Friday
continuing through the weekend with flow aloft becoming more
zonal. Weak subsident flow will keep conditions dry. Winds
remain light under surface high pressure with winds becoming
easterly for the weekend. 925mb temperatures range 16-21C
supporting highs in the low to mid 80s in most spots, perhaps a
tad cooler in the immediate coastal areas where sea
breezes/onshore flow will be prevalent. Surface high pressure
pushes offshore through the day Sunday as a mid-level trough
approaches from the west. The drier airmass should stay in place
during the day suppressing most shower development.

KEY MESSAGE 2...Unsettled weather for early to mid-week next week
with periodic chances for scattered showers and thunderstorms.

The pattern becomes more unsettled early next week with a mid-level
trough positioned across the northeast and a series of disturbances
moving through the flow. Overall there is a good signal for
increasing moisture with PWATs slightly above normal which will
support increased chances for periodic scattered showers and
thunderstorms early next week through mid-week. Temperatures
lean toward seasonable values in the low 80s.

&&

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

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

12Z Update...

Today...High confidence.

VFR. Winds WNW to NW for most terminals 5-10 kts. Sea breezes
likely for the coastal areas developing 18-20Z as NW winds
weaken. If Winds may become more variable later in the afternoon
and evening for the interior terminals. Sea breezes shift
toward S/SSE 21-00Z becoming S/SSW after 00Z.

Tonight...High confidence.

VFR. Light to calm winds overnight out of the SW.

KBOS Terminal...High confidence in TAF.

Higher confidence in a sea breeze developing after 18z this
afternoon. Otherwise, VFR with NW winds shifting to the E after
18z.

KBDL Terminal...High confidence in TAF.

Outlook /Friday through Monday/...

Friday through Sunday Night: VFR.

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

&&

.MARINE...
Forecaster Confidence Levels...

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

Tonight through Thursday Night

Winds shift to the NW early this morning as a cold front moves
through. Scattered showers and perhaps an isolated weak storms
are possible early this morning over the coastal waters as the
front slowly shifts eastward. Majority of the showers should
exit the outer coastal waters by 12Z this AM. Winds have fallen
below SCA criteria; however, lingering 5-6 ft seas will keep
SCAs going through the afternoon for the far southern inner
waters and through tonight for the southern outer waters.

High Surf Advisory remains in effect for exposed southern
coastlines through this evening. Prolonged period of higher
seas and SW flow have increased the risk for rip currents. The
higher risk continues today and decreases Friday. Seas recede
to 4 ft Thursday night with light winds over the waters.

Outlook /Friday through Monday/...

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

Friday Night: Winds less than 25 kt.

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

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

Sunday: Winds less than 25 kt.

Sunday Night: Winds less than 25 kt. Slight chance of rain
showers.

Monday: Winds less than 25 kt.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...High Surf Advisory until 8 PM EDT this evening for MAZ020>024.
RI...High Surf Advisory until 8 PM EDT this evening for RIZ006>008.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ235-
     237.
     Small Craft Advisory until 11 PM EDT this evening for
     ANZ254>256.

&&

$$

DISCUSSION...Mensch
AVIATION...Mensch/FT
MARINE...Mensch/FT