127
FXUS61 KBOX 231147
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
747 AM EDT Sun Aug 23 2026

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

&&

.KEY MESSAGES...

- Showers and storms around today, especially towards the CT
  River Valley where an isolated strong to severe thunderstorm
  or two is possible.

- Drier and warmer next week before rain chances make a return
  sometime Thursday/Friday.

&&

.DISCUSSION...
KEY MESSAGE 1...Showers and storms around today, especially towards
the CT River Valley where an isolated strong to severe thunderstorm
or two is possible.

Weak low pressure just off to our northeast continues to aid in
continued NE low level flow this morning, keeping overcast skies
over southern New England. Chances for spotty showers continue
primarily towards Nantucket and the outer Cape where showers are
just offshore and continuing to move off to the northeast. Aside
from these, misty and foggier conditions continue this morning
across the region.

The main thing to keep an eye out for today will be the chances for
some showers and storms towards the afternoon. Showers tracking
across New York associated with the approaching cold front will
approach western MA and CT towards the late morning/early afternoon
hours. The low pressure to our northeast loosens its grip over
southern New England as more southerly winds take hold in the late
morning/early afternoon hours, advecting in dewpoints in the 70s.
Increased humidity along with diurnal instability may enhance the
risk for storms in the interior turning strong to severe. Even with
cloudier skies inhibiting instability a bit, model soundings and CAM
guidance have MUCAPE values around 1500-1800 J/kg over the CT Valley
in the afternoon, and MLCAPE values to around 1200-1300 J/kg with
limited capping in the soundings. Effective bulk shear values around
40 kt will also aid in development of an isolated stronger to severe
storm or two, with the main risk of these storms being damaging
winds. PWAT values still around 1.25-1.5" in the afternoon ahead of
the front will also keep the risk for some torrential downpours in
play. The interior remains in a Marginal (1/5) risk for severe
weather today considering this environment.

Outside of this risk of showers and storms, the rest of the region
can expect to remain mostly dry, albeit dreary. Humid conditions
prevail with highs in the upper 70s.

KEY MESSAGE 2...Drier and warmer next week before rain chances make
a return sometime Thursday/Friday.

The cold front to our west passes through the region heading into
Monday, clearing skies quickly in its wake. Drier post-frontal air
flows into the region, noted by dew points falling into the 50s and
low 60s and PWATs to an inch and lower. Temperatures return to more
seasonable levels in the 70s and 80s, though it should feel more
comfortable than today given the reduced humidity. High pressure
steadily builds in through Tuesday into Wednesday as ridging takes
place of the troughing from Quebec that will continue to shift off
to the east. Clear skies and dry weather prevail through this period.

Greater uncertainty reenters the forecast towards Thursday and
Friday with the approach and development of another shortwave over
the Great Lakes. Ensemble and deterministic guidance does hint at
the return of elevated moisture towards this time period, along with
rain showers. Latest ensemble guidance has PWAT values returning to
around 1.5" Thursday afternoon into Friday, along with more
southerly flow towards the surface. Inconsistencies remain among the
ensembles, though, regarding the track of the low associated with
the shortwave. This also leads to discrepancies regarding the timing
of any showers.

&&

.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...

Today and Tonight...Moderate confidence.

IFR with localized LIFR this morning. Ceilings improve to MVFR
through the day. Improvements to VFR should occur overnight
from W to E as the front pushes through southern New England.
Scattered showers are possible this morning and afternoon. and
Low chance of a t-storm in the afternoon for western terminals
(BDL). ENE winds will gradually shift to the S/SW this
afternoon and evening at 6-12 kts. Light SW winds overnight less
than 8 kts.

Monday...High confidence.

Post-front, skies clear and VFR conditions return. Breezy SW
winds sustained around 10 kt with gusts to 20 kt.

KBOS Terminal...Moderate confidence in TAF. Some uncertainty
regarding timing of showers today, but more likely in the
afternoon (17-21Z). Few -SHRA or -DZ possible this morning.

KBDL Terminal...Moderate confidence in TAF. Given scattered
nature of possible TSRA towards BDL in the afternoon, maintained
in TAF as PROB30.

Outlook /Monday Night through Thursday/...

Monday Night: VFR.

Tuesday: VFR. Breezy.

Tuesday Night: VFR.

Wednesday: VFR. Breezy.

Wednesday Night: VFR.

Thursday: VFR. Slight chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Monday...High confidence.

Winds and seas are expected to remain below Small Craft Advisory
criteria through tonight. However, gusts could get close to this
criteria during the day Monday following the cold front passing
through tonight. Patchy fog over the waters tonight will clear
following the front as well.

Seas remain between 2-4 ft with 5 ft seas possible tonight in
the far ocean waters. Winds shift more S to SW today, continuing
through Monday.

Outlook /Monday Night through Thursday/...

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

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

Wednesday through Thursday: Winds less than 25 kt.

&&

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

&&

$$

DISCUSSION...Hrencecin
AVIATION...Hrencecin/Mensch
MARINE...Hrencecin