Plaistow, New Hampshire 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

761
FXUS61 KGYX 252240
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
640 PM EDT Wed Jun 25 2025

.SYNOPSIS...
Drier air will work into the region tonight bringing relief from
the humidity into Thursday. Mostly dry conditions will prevail
Thursday into Friday, although a front southwest of New England
could lead to some showers at times across New Hampshire.
Chances for showers increase late Friday with a soaking rain
Friday night into Saturday as low pressure crosses New England.
Weak high pressure will bring a drying trend Sunday into Monday
with temperatures and humidity increasing ahead of a cold front
Tuesday.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
630 PM Update...Little change to the going forecast. Cooler and
drier air will continue to move southward into the forecast area
tonight. Increasing clouds are likely well after midnight as WAA
once again gets going.

Previously...

Another hot day today, but relief is in sight as a cold front
drops through the forecast area.

Cumulus has been present much of the day throughout the forecast
area, but growth has been limited by warm air aloft. The cold
front bringing some of this lift will push south this evening.
Consolidated shower chances a bit further south for this
evening as window will be closing on enough instability and
forcing. Main focus will be across southern NH and far southern
ME. Can`t rule out a rumble of thunder or two in stronger cells,
but deeper CAPE will be fleeting. Considering the dry air and
inverted V model soundings this afternoon, good mixing is
underway this afternoon. Thus stronger cells could also bring
some gusty winds.

Tonight, conditions will be more pleasant as overnight temps
fall into the lower 60s and 50s and a light breeze. Temps may be
slow to decrease in southern NH given the slow moving front and
low level mixing. Temperatures may still be in the 70s here
shortly after midnight.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
A very pleasant start to Thursday, but clouds will be thickening
and lowering into early afternoon. This cloud will eventually
bring the chance of showers, but there is uncertainty on
coverage and timing. Upper levels saturate quickly as moisture
pushes through Upstate NY and Quebec, but broad dry layer in the
mid and low levels. Believe this holds off measurable
precipitation until Thursday evening for the mountains and
foothills. Further to the south, low level moisture that has
been positioned just to the south of the forecast area mid week
will push north and showers across southern NH look to onset
earlier in Thursday afternoon.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
High pressure will retreat to the northeast Friday as a low
amplitude wave sends an area of low pressure across the eastern
Great Lakes. This system will bring increasing chances for showers
Friday afternoon followed by periods of rain Friday night into
Saturday morning. Precipitation chances will gradually diminish
Saturday night through Sunday as the low pressure system exits into
the Atlantic. Weak high pressure builds in Monday for mostly dry
conditions with increasing temperatures. A deeper trough will
approach Tuesday with temperatures continuing an upward trend with
increasing humidity ahead of a cold front. Latest guidance is
in decent agreement that this cold front will cross the region
near or just after peak heating favoring the development of
thunderstorms.

A period of cooler and cloudier weather is looking likely from
Friday into Sunday. A warm front is forecast to impinge upon the
area Friday bringing increasing clouds and chances for showers
Friday afternoon. Highs will mainly be in the 60s with the warmest
spots across eastern zones where there will be more sunshine Friday
morning. The 12Z model suite brings a surface low WSW to ESE across
New England Friday night into Saturday morning. This will likely
bring a widespread soaking rain to much of the area. PWATs will be
on the increase Friday night approaching 1.75 inches by Saturday
morning along with warm clouds depths greater than 12KFT. The track
of the low will keep the best instability well to the south of the
area that should preclude rainfall rates from reaching their full
potential given the high PWATs and deep warm cloud depths. Current
QPF forecast from Friday through Saturday is around 0.75 to 1.25
inches south of the mountains with 1.5 to 2.25 inches across the
mountains and north. WPC has the forecast area in a Marginal Risk
for excessive rainfall through the duration of the event, which
seems reasonable given the high PWATs but lack of instability.
Steady rain will transition showers late Saturday into Saturday
night with highs on Saturday mainly in the 60s.

Low pressure will be offshore by Sunday while subtle waves aloft
will keeps low chances for showers in the forecast. Highs on Sunday
will range from the upper 60s north to mid 70s across the south.
Weak high pressure will build in for mostly dry conditions Monday
with highs climbing into the 80s. Temperatures and dewpoints will
continue to rise into Tuesday that will foster an unstable airmass
ahead of an approaching cold front. Models are in good agreement at
this time range that a front will cross sometime Tuesday afternoon
through Tuesday night that will bring chances for thunderstorms.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Short Term...Afternoon cumulus will dissipate later this evening
with VFR conditions expected to continue. Still a few -SHRA
possible in southern NH this afternoon and evening, but dry
trend expected overnight and much of Thursday.

Long Term...Mainly VFR Friday. Clouds thicken and lower Friday night
with RA likely bringing at least periods of MVFR into Saturday
morning. Conditions will improve some late Saturday into Sunday
morning with a return to prevailing VFR Monday.

&&

.MARINE...
Short Term...Below SCA conditions expected to continue as a cold
front passes the waters today. Gusty NE to N winds continue
tonight, but will tend to slacken Thursday morning as high
pressure nears from the NW.

Long Term...A warm front approaches the waters Friday followed by an
area of low pressure crossing Saturday. This system will bring
increasing easterly flow with winds generally below 25 kts. The
persistent easterly flow will bring seas to 5 feet Saturday into
Monday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...Heat Advisory until 7 PM EDT this evening for NHZ012-013.
MARINE...None.

&&

$$

SYNOPSIS...
NEAR TERM...Cornwell/Ekster
SHORT TERM...Cornwell
LONG TERM...Schroeter
AVIATION...
MARINE...