Belfast, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

436
FXUS61 KGYX 250709
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
309 AM EDT Fri Jul 25 2025

.SYNOPSIS...
The heat and humidity will peak today ahead of an approaching
cold front with heat indices climbing above 90 degrees south of
the mountains. The front will bring scattered strong to
possibly a few severe storms this afternoon. High pressure
builds in behind the front Saturday with seasonable temperatures
and lower humidity. High pressure is quick to exit as the next
system moves in Sunday although showers and thunderstorms may
remain south of our region.

&&

.NEAR TERM /TODAY/...
No changes from the previous forecast thinking with respect to
the hot and humid conditions today and few strong to severe
storms this afternoon. The Heat Advisory remains unchanged.
Over the past 24 hours CAMs have generally trended down on
instability for storms owing to a faster frontal passage and a
shorter window to destabilize the atmosphere. Still, the latest
HREF mean brings a corridor of MU CAPE of 1000 to 1500 J/kg
across southern NH into the coastal plain of Maine beneath an
area of deep layer shear 25 to 35 kts. This will be enough for a
few organized updrafts with latest CAM guidance suggesting some
clusters and semi-descrete pulse storms for convective mode.
The primary threat will be strong to damaging winds from any
organized clusters or small line segments and pulse storms will
bring the threat from downburst winds. Marginal shear and poor
mid level lapse rates will limit the hail threat with the latest
UH tracks from the HREF suggesting any hail producing updrafts
will stay just south of the area and possibly into the coastal
waters. The time window for strong to severe storms will
generally be between 2 PM and 6 PM with drier air aloft causing
instability to wane well before sunset.

Clouds associated with the incoming cold front are already
starting to move into northern zones early this morning. Clouds
will continue to increase through the morning with partly to
mostly cloudy skies likely around mid day into the afternoon.
The faster frontal passage may allow for skies to trend to
mostly clear late afternoon into this evening from north to
south. Highs will range from the mid 70s near the Canadian
border to the low 90s along the coast into southern NH. Dew
points will be near 70F and this will bring heat indices 95 to
100 degrees within areas under a Heat Advisory and low 90s
elsewhere south of the mountains.

&&

.SHORT TERM /TONIGHT/...
Drier air will continue to work into the area tonight with
mostly clear skies. Sheltered valleys across the north and CT
Valley will see the potential for some radiational fog to
develop if winds can go calm. Lows tonight will be much cooler
ranging from the low 50s north to low 60s across the south.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Overnight long term update...Have incorporated the 01z NBM into
the forecast for the long term. The biggest change was to lower
PoPs fairly significantly for Sunday and Sunday night as at
least for the time being it looks like showers and storms may
remain to our south.

Previously...

High pressure builds in for Saturday as Friday`s cold front
continues to push farther to the south, bringing a dry day to
the area. It won`t feel much cooler temperature-wise with highs
only coming down slightly into the low-mid 80s, but it will be
noticeably less humid as dewpoints will be mostly in the 50s.
Light southerly flow brings increasing moisture Saturday night,
which may result in patchy fog and/or low stratus developing in
some areas. Otherwise, low temperatures will be in the mid 50s
to lower 60s.

Chances for showers and storms return on Sunday as the high
shifts east in response to an incoming shortwave aloft. There
are some discrepancies in the models of the location/amplitude
of the wave, so confidence is currently low on which area(s)will
see the better chances or the amount of coverage. That said,
there is more of a signal in the ensembles for southern and
central NH into SW ME as seeing the better chances at this
point.

Once this wave passes, high pressure builds in and then quickly
becomes centered to the south and east the area early next
week. This will bring a return to increasing heat and humidity
with heat indices possibly getting back into the lower 90s over
some of the area ahead of a frontal boundary that looks to cross
toward the middle of next week. Wednesday may start to see
downward trend in the heat/humidity, but that depends if that
front has cleared the area by then. Isolated showers and storms
are possible on Monday with increasing chances Tuesday and maybe
into Wednesday as the front gets closer to the region.
Confidence is much higher in the cold front clearing the area by
Thursday with temperatures cooling back down into the mid 70s
to lower 80s. The upper air pattern shows a troughing pattern
developing across eastern Canada into the Northeast US for the
second half of next week, so we may still see a few showers.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
Short Term...Increasing low level moisture may allow for some
patchy fog at KAUG, KRKD, and KLEB for a couple hours early this
morning with mainly VFR for all sites after sunrise. A cold
front will bring scattered storms across the area from 18Z to
around 22Z while coverage looks to limited to have confidence
to put in the TAF. Mostly clear skies tonight may allow for some
radiational fog to develop at KLEB and KHIE. Otherwise VFR is
likely to prevail tonight into Saturday morning.

Long Term...VFR Saturday, but patchy fog may develop Saturday
night into early Sunday. Sunday looks to be mainly VFR. VFR
for much of the area Monday, and then chances for precipitation
increase going into Tuesday.

&&

.MARINE...
Short Term...SW winds will generally drop and stay below 25 kts
around sunrise with seas subsiding. SCAs remain in effect until
8 AM with conditions likely to stay below SCA thresholds into
Saturday. A cold front crosses the waters this afternoon which
will bring a few strong to severe storms that may remain strong
as they track over the waters. The threat for storms will
diminish after 6 PM.

Long Term...Conditions are expected to largely remain below SCA
levels for the weekend through the middle of next week. High
pressure centered west of the waters will bring a northerly flow
across the waters Saturday, but an afternoon seabreeze will
shift winds to more southerly by the afternoon. Prevailing
southerly flow will return by Saturday night and Sunday as a low
pressure and frontal boundary approach and shift the high to
the east. High pressure then builds across the waters around
Monday and then shifts to the east through the middle of next
week as another frontal boundary approaches.

&&


.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Heat Advisory from 10 AM to 8 PM EDT Friday for MEZ018>020-
     023>025-033.
     Beach Hazards Statement from 8 AM EDT Friday through Friday
     evening for MEZ027-028.
NH...Heat Advisory from 10 AM to 8 PM EDT Friday for NHZ006-008>015.
MARINE...Small Craft Advisory until 10 AM EDT Friday for ANZ150>154.

&&

$$


NEAR TERM...Schroeter
SHORT TERM...Schroeter
LONG TERM...Combs/Ekster