Area Forecast Discussion
Issued by NWS Boston, MA

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168
FXUS61 KBOX 101201
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
801 AM EDT Mon Aug 10 2026

.WHAT HAS CHANGED...
Forecast remains on track.

&&

.KEY MESSAGES...

- Above normal temperatures and humidity continues through
  Tuesday. Relief from the heat & humidity comes late week.

- Unsettled weather continues this week with shower and
  thunderstorms chances returning this evening as well as
  Wednesday night/Thursday morning.

&&

.DISCUSSION...
KEY MESSAGE 1...Above normal temperatures and humidity
continues through Tuesday. Relief from the heat & humidity
arrives for the weekend.

After a brief respite from the humidity this morning, dewpoints
will start climbing back into the upper 60s to low 70s once the
sun comes up. Temperatures should be a tad cooler today....
roughly 85-89 instead of the 90+ we`ve been seeing lately.
Humidity will linger through Tuesday, but both temperatures and
dewpoints will slowly begin to trend lower throughout the week,
bringing much needed relief to southern New England by Friday.
High temps heading into the weekend likely near 80 with
dewpoints dropping into the 50s, possibly even the 40s in the
higher elevations.

KEY MESSAGE 2...Unsettled weather continues this week with
shower and thunderstorms chances returning this evening as well
as Wednesday night/Thursday morning.

A passing cold pool across northern New England should help to
generate CAPE values of 750-1,250 J/kg by late this afternoon.
Combined with a one-two punch from a passing warm front and
trough axis moving through southern New England, some scattered
showers and thunderstorms could pop later this evening. CAM
guidance is once again struggling to resolve these storms, with
some models indicating storms over NW MA, others show W CT, and
others still keep storms confined to the Albany/NYC metro
regions. Confidence is on the lower end as far as timing and
placement, but currently thinking late afternoon into the sunset
hours with highest chances for a strong to severe storm forming
along the CT River Valley. A few showers could stray as far
east as the ORH-PVD corridor; however, if these showers move
that far east, they should be sub- severe.

Tuesday and Wednesday should remain dry and mostly sunny,
pleasant days. But by Wednesday night/Thursday morning, a low
pressure system sitting over the Hudson Bay will be pushing
south/southeast into southern Quebec and New England. A few
associated upper-level shortwaves and a cold front will likely
be the catalyst for another round of thunderstorm chances;
however, the main limiting factor will be the time of day the
front pushes through. If the front hits the eastern MA coast by
early Thursday afternoon, we`d expect weaker instability and a
lower thunderstorm risk. However, if the front stalls or moves
slower, then the risk for storms would increase, and so would
the chance for any one storm to reach severe levels.

&&

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

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

12z TAF Update:

Today: Generally high confidence, but moderate confidence on
timing/probability of TSRA.

Mainly VFR; hazy-looking skies from smoke possible. Light N
winds flip to SW by the afternoon 5-10 kts. Sea breeze likely at
BOS 13-15Z out of the ESE around 10 kts. Sea breeze possible at
PVD late morning through first half of afternoon with SSE
winds.

SHRA/TSRA look to develop late in the day, starting as soon as
21z at BDL with the higher risk after 23Z. Confidence decreases
in TSRA as the activity moves E/ESE toward ORH and further east
terminals (00-05Z). Given the isolated nature, kept as VCTS for
BDL. Lower probabilities and confidence have kept mention of
TSRA out of the terminals east of BDL at this time.

Toight: High confidence.

VFR. Sea breeze at BOS kicks out 23-01Z with winds shifting to
SW. SW winds 5-10 kts shift to WSW/W overnight.


KBOS Terminal...Moderate confidence in TAF. Generally VFR.
Wildfire smoke may be visible aloft today. Seabreeze likely to
develop between 14-15z, earliest 13Z. Reduced confidence on when
it will kick back SW, but more likely in the 23-01Z timeframe.
Low probability for a SHRA/TSRA after 01-06Z. Too low to include
in TAF at this time.

KBDL Terminal...Moderate confidence in TAF. Wildfire smoke aloft possible.
Potential for scattered SHRA or a TSRA after 21z, but moreso
after 23Z. If any storms develop, a stronger storm is possible
with gusty winds, frequent lighting, and brief IFR visbys.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Wednesday: VFR.

Wednesday Night: VFR. Chance SHRA.

Thursday: VFR. Breezy. Chance SHRA, slight chance TSRA.

Thursday Night: VFR. Slight chance SHRA.

Friday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday... High Confidence.

Winds return to SW this morning. Local sea breezes along the
east coast of MA. Relatively light seas across the waters
through tonight. Could see some breezy winds near 20kts later
this evening into Tuesday morning.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Wednesday Night: Winds less than 25 kt.

Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers, slight chance of thunderstorms.

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

Friday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Slight chance of rain showers.

&&

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

&&

$$

DISCUSSION...McMinn
AVIATION...McMinn/Mensch
MARINE...McMinn