759
FXUS61 KBOX 052251
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
651 PM EDT Tue Aug 5 2025

.SYNOPSIS...
Other than spot showers over western New England through
Thursday, dry weather with temperatures running around or
slightly cooler than normal through the end of the week.
Warming trend this weekend into early next week with the potential
for 90 degree heat and increasing humidity returning Sunday into
Monday. Chance of showers or thunderstorms early next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Key Messages:

* Mainly dry weather tonight, other than a spot shower or two
  in far western MA thru sundown.

* Lows mid 50s to lower 60s.

Moderately strong onshore ENE flow in conjunction with hazy
conditions associated with a sizable concentration of smoke
aloft has led to temps running a few degs cooler than normal in
the mid 70s to near 80. HRRR-Smoke progs show the better chance
at hazy/smoky conditions tonight being more concentrated over
interior Southern New England, although it likely will not
restrict visibility very much. A few convective showers could
still develop across northwest MA through sundown but the vast
majority of the time is dry. We probably will see another reddish
sunset again tonight though. Otherwise, the remainder of the
evening stands to be quiet with lows in the mid 50s to lower
60s.

&&

.SHORT TERM /WEDNESDAY NIGHT/...
Key Messages:

* Hazy/opaque skies from smoke suspended aloft on Wed, but
  mainly dry weather otherwise. Cooler highs mid 70s-near 80.

Wednesday and Wednesday Night:

Governing features on the large-scale are little changed, with
slight cooling of temperature profiles. Regarding haze/smoke
forecast for Wed, 12z HRRR- Smoke near-surface concentrations
are quite a bit lower than prior days, so not thinking we`ll see
visbys reduced, but higher concentrations visualized in the
HRRR- Smoke vertically- integrated smoke product suggest another
opaque/milky-looking sky condition. The combination of somewhat
filtered sun with slightly cooler 925-850 mb temps and onshore
flow should keep temps in the mid 70s to near 80, cooler east.
There could be a spot shower in far western MA, but the coverage
of them should prove less than today as instability progs are
even weaker than that of today.

Dewpoints are a touch higher Wed evening, so while the vast
majority of the area Wed night is dry, river valley fog could
develop in the western interior valleys. Similar lows in the mid
50s to around 60.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Key Messages...

* A few showers and thunderstorms possible Thursday, then dry
  through the weekend before afternoon showers/storms may return
  first half of next week.

* Temperatures steadily climb each day, with low 90s and higher
  humidity by Sunday and Monday.

High pressure over northern New England settles south becoming
centered over the Gulf of Maine late week then further offshore
through the weekend. This brings subsidence and mostly dry weather
through the bulk of the extended forecast. The only exception
through the weekend will be Thursday when, despite onshore flow into
eastern SNE, dewpoints may reach the 60s in interior NW MA
contributing to marginal instability and a chance for showers and
garden variety thunderstorms.

Temperature-wise high pressure directs cooler easterly flow into the
region through Thursday. Then, Friday into the weekend high pressure
shifts offshore and a mid level ridge builds overhead, increasing
warm SW flow. This will pump temperatures back up into the low 80s
by Friday, mid 80s by Saturday though humidity remains comfortable.
By Sunday into the early part of next week 90s are once again in the
cards while dewpoints climb back into the mid to upper 60s making it
feel more humid. This also contributes to renewed afternoon shower
and thunderstorm chances next week.

&&

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

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

00z TAF Update:

Tonight: Moderate confidence.

Mainly VFR, but patchy stratus and fog may develop across
Cape/Islands and SE coastal MA. Light NE wind.

Wednesday: High confidence.

Mainly VFR, though wouldn`t rule out visbys around 5-6 SM in
HZ/FU from smoke at BAF-BDL. Smoke suspended aloft could still
hamper visual approaches. NE winds 5-10 kt.

Wednesday Night: Moderate confidence.

VFR, though patchy radiation fog possible in the river valleys
and also potentially along the south coast. Light winds.

KBOS terminal...High confidence in TAF.

KBDL terminal...High confidence in TAF.

Outlook /Thursday through Sunday/...

Wednesday Night through Friday Night: VFR.

Saturday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Wednesday Night...High confidence.

Tranquil boating conditions expected through Wed night. NE winds
around 15-20 kt thru tonight, which then ease to 10-15 kt Wed
and into Wed night. Seas 3 ft or less all waters.

Outlook /Thursday through Sunday/...

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

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert until midnight EDT tonight for MAZ002-003-
     008>011.
RI...None.
MARINE...None.

&&

$$

SYNOPSIS...Loconto/BW
NEAR TERM...Loconto
SHORT TERM...Loconto
LONG TERM...BW
AVIATION...Loconto/BW
MARINE...Loconto/BW