505
FXUS61 KBOX 261951
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
351 PM EDT Thu Jun 26 2025

.SYNOPSIS...
High pressure builds into the Gulf of Maine tonight into Friday,
maintaining mostly cloudy conditions, cooler temperatures and
modest onshore breezes. A warm front tries to lift northward
Saturday with a risk for showers and thunderstorms, along with
warmer and more humid weather for the southern half of Southern
New England. Seasonably warm and dry for Sunday. Temperatures
then warm up into the mid to upper 80s again early next week,
along with daily chances for showers and thunderstorms.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
305 PM Update:

Key Messages:

* Cloudy with continued onshore flow allowing for cooler
  nighttime lows upper 50s/low 60s.

* Hit or miss rain showers thru midnight but majority of
  Southern New England stays dry.

Details:

Today`s been quite a bit cooler and noticeably less humid,
driven by NE onshore flow with sfc ridging extending into
ME/northern NH. And by quite a bit cooler, 24 hour temperature
anomalies are around 20-25 degrees cooler. Considerable
cloudiness has also resulted, and that will continue into
tonight as a weak disturbance aloft working through central NY
moves ESE through Southern New England during the first part of
the evening. Radar mosaic is showing some returns but most of
these showers are having a tough time reaching the ground.
Wouldn`t rule out a passing shower thru midnight but think the
radar presentation`s bark is worse than the bite and the
majority of the time is dry. High pressure then makes greater
southward inroads during the overnight with any light rain
showers pulling southward/offshore, with dry weather. Still
overall cloudy tonight with lows in the upper 50s to lower 60s
with a continued E to NE wind.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
305 PM Update:

Key Messages:

* Partly to mostly cloudy Friday, peeks of sun late in the day.
  Highs in the upper 60s to mid 70s.

* Increasing clouds and possible showers Friday night, starting
  to turn a little more humid but still tolerable.

Details:

A 1024 mb sfc high pressure will be building SE from ME/NH with
ridging extending westward from it to the Berkshires. It now
looks as though Friday ends up being drier than not, with the
better chance for rain showers being in the narrow/pinched warm
sector west of the Berkshires and Litchfield Hills. Although we
start off mostly cloudy, it`s possible eastern areas could see
some breaks in the cloudiness toward some peeks of sun during
the afternoon. Think there should be enough breaks in cloudiness
to allow highs to rise into the upper 60s to mid 70s with
tolerable levels of humidity (dewpoints in the lower to mid
50s).

Increased cloud cover toward overcast then returns Fri evening,
along with a rise in dewpoints/humidity level in the overnight
as a warm front tries to lift northeastward. That being said,
with rain across interior northern New England falling into the
ridge helping to reinforce it, I`m not optimistic we`ll truly
break out into the warmer and significantly more humid airmass
that lies well to our south and west. Still, increasing risk for
showers arriving toward the second half of the overnight, with
lows in the upper 50s to lower 60s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
350 PM Update:

Key Messages:

* Scattered showers possible Saturday

* Temperatures warm into the 80s going into next week

Saturday...

Saturday looks to be the trickiest part of the forecast. A low
pressure system moving through southern Ontario brings a warm
front into New England Saturday morning; however, there is a
large amount of uncertainty on how far north the warm front will
lift. Ensemble guidance is pretty split on where the warm front
ends up... ECMWF ensemble pushes it up into Massachusetts, the
GEFS drapes it across Connecticut, and the Canadian ensemble
keeps it further southeast in New York. Saturday`s temps will
really depend on how far north the front gets. If it favors the
ECMWF track, much of southern New England could see temps near
80; however, given that we`ll also be seeing onshore flow from a
high sitting over the northern Atlantic, we elected to go with
a mix of GEFS and Canadian guidance... keeping the 80 degree
temps confined to the CT River Valley and Willimantic, CT areas
and low to mid 70s across the rest of southern New England.

Regardless of where the warm front sets up, Saturday looks to
feature scattered showers, and possibly thunderstorms, across
southern New England. Guidance is currently indicating 40-50%
chance of anywhere in MA and northern RI reaching a 24-hour QPF
total of 0.1"... only 30-40% for CT, southern RI, and the Cape
and Islands.

Sunday - Wednesday...

Briefly drier Sunday and Monday, but storm potential returns
Tuesday with the arrival of a cold front. Dry conditions return
for the middle of the week. Temperatures in the mid 80s to low
90s return for the first half of the week. We`ll also likely see
dewpoints return the the upper 60s to low 70s, creating quite
muggy conditions.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
Forecaster Confidence Levels...

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

18Z TAF Update:

Through Tonight: High confidence.

Mainly BKN/OVC VFR bases; could be some passing, spotty rain
showers moving southeast rest of the afternoon thru about 04z
Fri. However these showers should be light enough to not
restrict visby. NE to E winds around 10 kt thru this evening.

Friday: High confidence.

VFR continues, with dry weather. E to SE winds 5-10 kt.

Friday Night: Moderate confidence.

VFR early, although categories deteriorate from west to east
after 03z to IFR levels as stratus develops along with areas of
mist/fog. SE winds around 5 kt.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Saturday through Tuesday/...

Friday Night: Mainly VFR, with local IFR possible. Chance SHRA.

Saturday: Mainly IFR, with local MVFR possible. Breezy. Chance
SHRA, chance TSRA, patchy BR.

Saturday Night: IFR. Chance SHRA, slight chance TSRA, patchy
BR.

Sunday: Mainly VFR, with areas IFR possible. Slight chance
SHRA, patchy BR.

Sunday Night: Mainly VFR, with areas IFR possible. Patchy BR.

Monday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

NE to E winds range from 15-25 kt, with waves 3-5 ft tonight
through Friday night. Strongest winds and highest seas over the
southern outer waters. Issued SCA through Friday on the southern
outer waters, though conditions are somewhat borderline. Mainly
dry weather, although could see some passing showers tonight
but shouldn`t restrict visbys.

Outlook /Saturday through Tuesday/...

Friday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Chance of rain showers.

Saturday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers, slight chance of thunderstorms, patchy
fog. Visibility 1 to 3 nm.

Saturday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Chance of rain showers, chance of
thunderstorms, patchy fog. Visibility 1 to 3 nm.

Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain showers, patchy fog. Visibility 1 to 3 nm.

Sunday Night through Monday: Winds less than 25 kt. Areas of
seas approaching 5 ft. Patchy fog. Visibility 1 to 3 nm.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 8 PM this evening to 8 PM EDT Friday
     for ANZ255-256.

&&

$$

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