Westbrook, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

911
FXUS61 KGYX 260758
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
358 AM EDT Sat Jul 26 2025

.SYNOPSIS...
Areas of smoke from Canadian wildfires arrive overnight and
continue through Saturday afternoon. High pressure moves
overhead today, with seasonable temperatures and lower
humidity. High pressure shuffles east as the next system moves
in Sunday with chances of showers and storms. Heat and humidity
begin to build again early next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
4am Update...Quick update to relay Air Quality Alert for Maine.

Previous Discussion...
High pressure settles over the region today bringing fair
conditions. While yesterday`s cold front brought some afternoon
relief, today will still see highs pushing into the 80s.

Smoke entered the region Friday evening, pushing across the
area overnight. Low level smoke has been impressive for a far
remote source, with overnight observations reading 4 to 6 mile
visibility across the forecast area. HRRR/RAP smoke models
continue the plume over the area today, gradually decreasing in
coverage and intensity as the day goes on. The lack of daytime
mixing will help keep greater smoke content aloft from mixing
down, but will also prolong some areas due to largely stagnant
air. A afternoon seabreeze along the coast stands chance at
thinning haze/smoke, but the better chance for relief may not
come until flow turns southerly tonight.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
High pressure will move over the Gulf of Maine tonight, bringing
a southerly return flow into NH and ME. It will be subtle
initially, but increase into Sunday morning. After a mostly
sunny day, clouds thicken into Sunday. This, and the following
rain, will contain daytime highs in the 70s for southern and
central areas. A 80 degree rating will be possible towards
central ME where clouds may not become as thick as southern
points.

The main focus Sunday will be a rain along increased PWAT values
advecting east along a channel of IVT. HREF and NBM bring
measurable precip first into NH early Sunday morning, expanding
east into southwestern ME through early afternoon. Associated
moisture is transient however, and as the parent low tracks
north into Quebec Sunday evening, rain becomes more showery and
lighter. While PWATs push above 1.5 inch briefly, warm cloud
layers remain around 10kft. Thus warm rain processes won`t be
optimal. Additionally, backbuilding or training of
showers/storms is not expected, but could still occur given a
more favorable environment to the west. Due to continuing
onshore flow across much of the area, surface instability is
difficult to build through the day. This will further lower
additional shower/thunderstorm development come afternoon.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Behind exiting wave, shortwave ridging builds in for Monday,
providing the subsidence for a mostly dry forecast. However, the
heat and humidity will ramp back upward with 850mb temps
supporting highs in the upper 80s to lower 90s, and dewpoints
may be enough to bring heat indices into the mid 90s in some
areas.

Another wave may bring some shower activity Monday night, mainly
across northern areas, and then chances for showers and storms
further increase on Tuesday and Tuesday night as a cold front
approaches the region with daytime temperatures and heat index
values potentially even climbing a degree or two on top of Monday`s.
There remains uncertainty in how quickly the front will push south
of the area, so Wednesday could end up being drier and slightly
cooler or still pretty warm with lingering chances for showers and
storms.

There`s higher confidence in the front having cleared the area by
Thursday with cooler and drier air settling in for Thursday and
Friday as high pressure builds toward New England from the west.
Aloft, an upper low will likely be somewhere near the Canadian
Maritimes with troughing extending southward into the Northeast.
So it`s possible a shortwave or two bring a few showers from
time to time. Of note: The global models do indicate low
pressure trying to develop along the frontal boundary, but the
ECMWF is not as far south with front as other guidance. If this
is the case, southern and coastal areas may see higher
precipitation chances toward late week. However, this is a week
out, and confidence is low.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Short Term...Areas of wildfire smoke and haze bring MVFR
visibility restrictions to most terminals into Saturday, likely
lingering the longest around HIE and LEB into midday. It is
possible some calm conditions allow for radiation fog to form in
the deeper river valleys...like near LEB and HIE through this
morning. Clouds thicken and lower Sunday morning as SHRA invade
from the west for most NH terminals and far western ME
terminals. MVFR to IFR ceilings will be possible Sunday morning
through the afternoon.

Long Term...Fog may then develop Sunday night into early Monday
morning, but then VFR is expected the rest of Monday. Tuesday
will see increasing chances for flight restrictions from showers
and storms as a front approaches, but low ceilings/fog look to
be a possibility Monday night or early Tuesday ahead of the
front. Depending on the speed of the front, chances for flight
restrictions and precipitation may linger into Wednesday.

&&

.MARINE...
Short Term...Light northwesterly wind continues this morning
behind a passing cold front. As high pressure pushes over the
waters, southerly return flow increases this afternoon through
Sunday. Winds and seas will remain below SCA thresholds thru
Sunday.

Long Term...Conditions currently look to remain below SCA
levels from Sunday through through much of next week. In
general, high pressure becomes centered east of the waters as a
weak front moves into the region Sunday followed by a more
potent front toward midweek. High pressure builds toward the
northeastern U.S. from the west late next week.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Air Quality Alert until 11 PM EDT this evening for MEZ007>009-
     012>014-018>028-033.
     Beach Hazards Statement from 8 AM EDT this morning through
     this evening for MEZ027-028.
NH...None.
MARINE...None.

&&

$$

NEAR TERM...Cornwell
SHORT TERM...Cornwell
LONG TERM...Combs