840
FXUS61 KBOX 142328
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
728 PM EDT Tue Jul 14 2026

.WHAT HAS CHANGED...
Canceled the Heat Advisory for much of MA, leaving it in effect
for northern CT, SE MA, and RI.

&&

.KEY MESSAGES...

- Hazy, hot and humid Wednesday.

- Strong thunderstorms possible late tonight into Wednesday.

- Dangerous rip currents and surf expected on south-facing
  beaches through Wednesday.

- Seasonable temperatures with less humidity for the second half
  of the week, though unsettled conditions with chances for
  showers and thunderstorms remain possible into this weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...Hazy, hot and humid Wednesday.

Tweaked the Heat Advisory headlines today due to a layer of
smoke aloft. This has been fairly opaque today, resulting in
lower temperatures this afternoon. Even more smoke is projected
for tomorrow, lowering confidence in reaching the Heat Advisory
threshold for most of MA. That said, most people will still
consider conditions to be at least warm and humid. Further
adjustments may be needed with later forecasts.

KEY MESSAGE 2...Strong thunderstorms possible late tonight into
Wednesday.

Strong convection over southeast Canada and northern New England
may dive south into our region late tonight into Wednesday.
Widely different answers in location and timing amongst the
convection-allowing models. Most keep showers and thunderstorms
out of southern New England. However, still thinking elevated
CAPE values of 1,000-1,500 J/kg are possible late tonight into
Wednesday. While this is likely not enough to result in severe
weather, cannot completely dismiss the idea of a few
thunderstorms, especially across northern MA.

KEY MESSAGE 3...Dangerous rip currents and surf expected on south-
facing beaches through Wednesday.

SW breezes expected today and again on Wednesday will build wave
heights into tonight to around 5-8 ft on the outer waters, then
start to lower into the 4-6 ft range for Wednesday, but
becoming longer in period. This poses a risk for dangerous rip
currents and higher surf, and though it`s often bullish in its
output, it is supported by NWPS high probabilities for rip
currents.

For that reason we`ve hoisted a Rip Current Statement through
early evening Wednesday for the southern coastline, with those
areas with south/southwest facing exposures most at-risk. There
should be fewer numbers of people at beaches at night but since
the waves look to be higher tonight, opted to not get cute with
the timing. the wave periods are on the shorter side today
which could reduce wave energy to an extent, as it`s often the
longer period waves which cause the biggest risk for rip
currents. Swim near vicinity of lifeguards and stay off jetties.

KEY MESSAGE 4...Seasonable temperatures with less humidity for
the second half of the week, though unsettled conditions with
chances for showers and thunderstorms remain possible into this
weekend.

The upper level ridge that has been dominating the pattern for
much of this week will start to slide more SE of the region
for the second half of the week as an upper level trough with
broad cyclonic flow to our north takes hold. A cold front passes
through the region late Wednesday into early Thursday morning,
which will help usher in more seasonable temperatures for the
back half of the week. 925 mb temperatures fall to generally
around 18-20C, which will be more supportive of high
temperatures in the 80s. Thursday may be slightly warmer
compared to later days due to breezy westerly winds and
resultant downsloping, but drier air overall and lower
temperatures aloft (as mentioned above) may only push highs into
the low 90s. After that, expect 80s to persist into the start of
next week.

Latest guidance is hinting at the possibility for a ripple in
the NW flow aloft later in the week that could lead to more
unsettled conditions. Guidance is also indicating a shift to
more southerly flow for the weekend and a surge in PWAT values
as a result. A surface low approaches from the west Saturday
and with more of a NE track as currently indicated, its fronts
would likely drag through the region and increase the risk for
showers and thunderstorms through the weekend. Exact timing is
still quite uncertain this far out, but ensembles and
deterministic guidance suites remain favorable for a wetter
end to the week, both on Saturday and Sunday.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

Tonight...High confidence.

VFR. Gusty SW winds may continue in some areas through tonight,
namely BOS, HYA, and ACK. Elsewhere, winds are already starting
to drop off a bit and will continue to do so heading into the
overnight period. Areas of LLWS remain a possibility through the
early nighttime hours tonight for terminals on the Cape and
Islands due to a LLJ moving overhead of these terminals.

Wednesday...Moderate confidence.

Mainly VFR conditions throughout, however some visibility
restrictions may be possible across western MA & CT due to
increasing near surface smoke from Canadian wildfires.
Additionally, tomorrow morning/afternoon some isol-sct showers
may be possible for northern terminals, however no mention of
VCSH/VCTS have been included at this time given the uncertainty
in timing and coverage. A low probability for showers or storms
returns in the afternoon as well, but confidence is once again
too low regarding timing, location, and coverage for any that
develop. Winds will become more W/NW around 10z, becoming gusty
20-25kt once again shortly after that.

Wednesday Night...High confidence.

VFR. Relatively light W to NW winds, going calm for some.

KBOS Terminal...Moderate Confidence. Minor visibility
restrictions are possible on Wednesday due to concentrations of
surface smoke from Canadian wildfires. Visibilities may drop to
around 5-6SM.

KBDL Terminal...Moderate confidence. MVFR visibility
restrictions are possible on Wednesday due to surface smoke from
Canadian wildfires.

Outlook /Thursday through Sunday/...

Thursday through Thursday Night: VFR. Breezy.

Friday: VFR.

Friday Night: VFR. Slight chance SHRA.

Saturday: VFR. Breezy. Chance SHRA, chance TSRA.

Saturday Night: Mainly VFR, with local MVFR possible. Breezy.
SHRA likely, chance TSRA.

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

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Wednesday Night: High confidence.

SCAs take effect today and were extended into Wednesday. SW
winds increase today to around 25-30 kt, with low prob of gusts
to gale force near the Cape and Islands today into tonight, with
seas building to 6-8 ft offshore by tonight. Seas then slowly
ease into Wednesday but should still be in the SCA range for
Wednesday. Potential for thunderstorms on the northern waters as
soon as overnight tonight into early Wed morning, with lesser
risk for thunderstorms on the southern waters Wed aftn/night.

Outlook /Thursday through Sunday/...

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

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

Friday: Winds less than 25 kt.

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

Saturday: Winds less than 25 kt. Chance of rain showers, slight
chance of thunderstorms.

Saturday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Rain showers likely, chance of thunderstorms.

Sunday: Winds less than 25 kt. Areas of rough seas. Chance of
rain showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory until 8 PM EDT Wednesday for CTZ002>004.
MA...Heat Advisory until 8 PM EDT Wednesday for MAZ017>021.
     Air Quality Alert until 11 PM EDT this evening for MAZ017>024.
     High Risk for Rip Currents through Wednesday evening for MAZ020>024.
RI...Heat Advisory until 8 PM EDT Wednesday for RIZ001>007.
     Air Quality Alert until 11 PM EDT this evening for RIZ001>008.
     High Risk for Rip Currents through Wednesday evening for RIZ006>008.
MARINE...Small Craft Advisory until 11 PM EDT this evening for ANZ230-
     231-236-250-251.
     Small Craft Advisory until 8 PM EDT Wednesday for ANZ232>235-
     237-254>256.

&&

$$

DISCUSSION...Belk/Hrencecin
AVIATION...Belk/Hrencecin/LaRocca
MARINE...Belk/Hrencecin