613
FXUS61 KBOX 040726
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
326 AM EDT Wed Jun 4 2025
.SYNOPSIS...
Summer warmth today through Friday with the heat peaking on
Thursday as highs reach 90 to 95 away from the immediate coast.
While an isolated shower/thunderstorm will be possible
Thursday, there will be a much better chance of scattered
showers and thunderstorms Friday some of which may linger into
Saturday. Seasonable temperatures will return this weekend into
early next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Key Messages...
* Plenty of sunshine and very warm today with highs 85 to 90 away
from the south coast but with comfortable humidity levels
* Some smoke/haze in the skies from the Canadian Forecast Fires
Details...
Mid level ridge axis builds into southern New England today. The
result will be plenty of sunshine and a very warm day. 925T warm to
between +20C to +22C and with a relatively dry airmass in
place...the stage is set for a very warm afternoon. High temps
should reach between 85 and 90 away from the south coast. Despite a
very warm afternoon...humidity levels will still be comfortable.
The other concern today is the HRRR/RAP indicate that some
smoke/haze will advect in aloft from the Canadian Forest Fires. Much
of this should be aloft so nothing like we experienced a couple
years ago. Nonetheless...still expect a smokey/hazy look to the sky
at times.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Key Messages...
* Dry & mild tonight with lows 55 to 65 degrees
* Hot Thu with highs 90-95 away from the immediate coast
Details...
Tonight...
Upper level ridging remains in control of our weather tonight.
Low temps will be rather mild tonight in the 55 to 65 degree with
the mildest of those readings in the urban centers. Winds will be
light from the southwest.
Thursday...
The heat will peak on Thursday. The upper level ridging and above
normal height fields will persist into southern New England. This
again will result in plenty of sunshine with 925T rising to between
+23C and +25C! This will result in a hot afternoon with high
temperatures reaching between 90 and 95 in many locations
away from the immediate coast. There also will be a bit of humidity
to the air with dewpoints in the lower to middle 60s. Heat Index
Values will climb into the lower to middle 90s in many
locations. While we are not anticipating any heat headlines...our
experimental NWS Heat Risk product indicates moderate impacts for
most individuals sensitive to the heat.
Lastly...while mainly dry and hot weather will be the story on Thu
we can not rule out isolated showers/t-storm or two. Given the lack
of forcing/upper level support...whether or not any isolated
activity is able to develop remains uncertain. The best chance will
be on any subtle sea breeze boundaries or some terrain
impacts/elevated heating. Again though if any activity is able to
develop it will be isolated/localized with the most locales
remaining dry.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Key Messages:
* Slightly cooler Fri, but temps still expected to be in the mid to
high 80s across southern New England.
* Several chances for showers/t-storms Fri into Sun, better chances
north. Heavy rain possible but details on timing and placement is
still uncertain.
* Brief dry weather for Monday.
Friday into the Weekend:
While Friday certainly looks to be cooler than Thursday, it`s also
looking to be a more active weather day. Southwest flow aloft with
weaker low-level winds interacts with subtropical moisture. This
should, once again, allow for several opportunities for showers/t-
storms in this period. GFS/GEFS continue to be the driest solutions
regarding 24-hour QPF probs; ECMWF and it`s ensemble probs have
dropped slightly from yesterday (down to widespread 10-20 percent of
24-hours QPF exceeding 1"); GEM and it`s ensemble continue to be the
wettest solutions, with widespread 40-50 percent probs of 24-hour
QPF exceeding 1" near/north of the Mass Pike. The weaker flow aloft
and lower instability may lead to less of a severe-weather risk, but
instead potential for heavy downpours/training of rain into Fri and
Sat; while the better potential for downpours based on current
ensembles looks to be in the northern third of Southern New England,
the exact placement is still in question.
With regard to temps, Fri is still quite warm with highs in the mid
80s, although temps then cool off for Sat and Sun with readings in
the mid 70s.
Monday:
Monday looks to be a brief break in the shower/t-storm activity as
weak high pressure builds in. Expect drier weather but temps around
seasonable levels before southeast flow returns and brings increased
cloud cover for Mon night.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06z TAF Update...
Today through Thursday...High confidence.
VFR conditions continue today through Thursday. SW winds of 10 to 15
knots develop later this morning/afternoon diminishing a bit
tonight. SW winds of 5-10 knots expected Thursday...but a few hours
of sea breezes may impact parts of the immediate coast. Low risk for
an isolated shower/t-storm Thursday afternoon.
BOS TAF...High confidence in TAF.
BDL TAF...High confidence in TAF.
Outlook /Thursday Night through Sunday/...
Thursday Night: VFR. Breezy. Slight chance SHRA, isolated TSRA.
Friday through Friday Night: Mainly VFR, with local MVFR
possible. Chance SHRA, isolated TSRA.
Saturday: Mainly MVFR, with local VFR possible. SHRA likely,
isolated TSRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
SHRA.
Sunday: VFR. Slight chance SHRA.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Today through Thursday...High confidence.
Upper level ridging will keep winds/seas below small craft advisory
thresholds through Thursday. However...some SW 20+ knot winds this
afternoon may result in some choppy seas.
Outlook /Thursday Night through Sunday/...
Thursday Night: Winds less than 25 kt. Seas locally approaching
5 ft.
Friday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers, isolated thunderstorms.
Friday Night: Winds less than 25 kt. Chance of rain showers.
Saturday: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers.
Saturday Night through Sunday: Winds less than 25 kt. Seas up
to 5 ft. Chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
evening for CTZ002>004.
MA...None.
RI...None.
MARINE...None.
&&
$$
SYNOPSIS...Frank/McMinn
NEAR TERM...Frank
SHORT TERM...Frank
LONG TERM...McMinn
AVIATION...Frank/McMinn
MARINE...Frank/McMinn