141
FXUS61 KBOX 151141
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
741 AM EDT Wed Jul 15 2026

.WHAT HAS CHANGED...
No significant changes. Monitoring sfc haze/smoke conditions for
the day as Canadian wildfire smoke continues to move in.

&&

.KEY MESSAGES...

- Very warm to hot today, but tempered by hazy/smoky conditions.

- Dangerous rip currents expected on south-facing beaches today.

- 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...Very warm to hot today, but tempered by
hazy/smoky conditions.

Very warm and muggy conditions across Southern New England open
the morning, with some areas early this morning still not
having dropped below 80 degrees, with dewpoints in the upper 60s
to low 70s to boot. After coordination with NWS Albany and NWS
Upton, we opted to retain the Heat Advisory given the poor
overnight recovery, but during the day it probably ends up
being borderline, with peak heat indices in the mid to upper
90s. This is partly due to the sagging cold front bringing a
drop in humidity levels, but more because we are again looking
at an influx of smoky/hazy conditions from the ongoing wildfires
burning in northern MN and western Ontario. Highs were adjusted
well below NBM values, with forecasts in the mid 80s to around
90.

We saw yesterday the influence of the hazy, milky-looking skies:
being a significant reduction in temperatures. Latest guidance
from the 00z HRRR-Smoke and 00z RRFS vertically-integrated smoke
progs show another considerable concentration of smoke aloft
today and also into Thursday too. But unlike yesterday, there
are now some notable concentrations of near-surface smoke
developing this afternoon across the southern half of Southern
New England and the northern mid-Atlantic. Think it`s overdone
but there`s some solutions offering reductions in visibility,
too, in the smoke layer. Ended up adding haze or smoke in the
zone forecast for today. I think based on the near-surface smoke
progs that you could smell this smoke today. Remains to be seen
if air quality alerts would be needed, and recall that those
are issued by state environmental agency partners, with our role
being to relay those. Also added haze in for Thursday based on
output in the longer forecast range in the 00z RRFS smoke progs.
Expect rather milky looking skies with red/orange
sunrises/sunsets today and again on Thursday, likely to temper
stronger heating both days.

KEY MESSAGE 2...Dangerous rip currents expected on south-facing
beaches today.

WSWly breezes over the southern waters combined with lowering wave
heights of 4-6 ft still will support a high risk for rip
currents for those beaches exposed to the south and southwest.
Swim near vicinity of lifeguards and stay off jetties today.

KEY MESSAGE 3...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 /12Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

12z TAF Update:

Through 18z Wednesday: High confidence.

MVFR/VFR reductions in vsby are expected with haze/smoke
overhead. Winds will be out of the W/NW winds around 10-15 kt,
with gusts to 25-28 kt for BOS & the Islands.

Tonight and Thursday: High confidence.

VFR, though hazy skies continue tonight into Thursday. W/NW
winds around 5-10 kt tonight, then increasing with gusts to 20
kt Thu.

KBOS Terminal...High confidence.

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

Outlook /Thursday through Sunday/...

Thursday through Thursday Night: VFR. Breezy.

Friday through Friday Night: VFR.

Saturday: Mainly VFR, with areas MVFR possible. Breezy. Chance
SHRA, slight chance TSRA.

Saturday Night: Mainly VFR, with local IFR possible. Breezy.
Chance SHRA, slight 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 Thursday: High confidence.

SCAs continue on the southern waters through today, with WSW
winds gusting to around 25-30 kt with seas in the 4 to 6 ft
range, shifting to W/WNW late today. Into Thursday, westerly to
west/northwest winds should be around 15-20 kt, falling below
SCA criterion.

Monitoring the risk for strong thunderstorms on the northeastern
waters early this morning, which could become strong and produce
lightning, erratic winds and hail. Otherwise, hazy/smoky sky
conditions are expected today and Thursday. Some areas of
reduced visibility could be possible due to this smoke.

Outlook /Thursday through Sunday/...

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

Friday through Friday Night: Winds less than 25 kt.

Saturday: Winds less than 25 kt. Chance of rain showers.

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft. Rain showers
likely, slight chance of thunderstorms.

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

&&

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

&&

$$

DISCUSSION...Loconto
AVIATION...Loconto/Guest
MARINE...Loconto