Pelham, New Hampshire 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

886
FXUS61 KGYX 250556
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
Issued by National Weather Service Caribou ME
156 AM EDT Fri Apr 25 2025

.SYNOPSIS...
Light rain showers possible this evening as a weak system
crosses the region. Friday will be another warm day as south
winds ahead of an approaching storm system moves into the
region. Showers are possible tomorrow afternoon before more
widespread rain moves into the area on Saturday as an area of
low pressure moves across New England. Rain showers and higher
elevation mountain snow showers linger on Sunday with a cool
mostly cloudy day. High pressure and warm weather returns by
Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
155 am update...
No major chgs needed with early morning update with showers
slowly dissipating as they head east into nrn New Hampshire.

Prev discussion blo...
A weak shortwave pass through the area this evening bringing a
few light rain showers. Mixing layer is very dry, so most rain
will be very light due to evaporation drying. A few wind gusts
could be possible in any stronger shower due to sub- cloud
evaporation, but overall most areas will remain dry. Shower
activity should mostly end by midnight tonight. Temperature
wise, onshore and southerly return flow has begun. This has
allowed a sea-breeze front to push inland this afternoon will
cooler temperatures this evening along the coast and a nice warm
evening across the interior areas. Temps will remain cool
across Maine with lows in the 40s. It will be warmer across
southern NH due to cloud cover and not having a onshore flow,
with lows around 50.

&&

.SHORT TERM /SATURDAY/...
Warm front begins to push north tomorrow with a sharp trend
upward in dewpoint temperatures as southerly flow becomes
established. Temperatures will run well above normal with highs
in the 70s and upper 70s for the lower Merrimack River Valley.
Cooler temperatures will remain along the immediate coast.
Instability showers are possible by the afternoon hours,
especially across Southern NH as the warm front pivots north
through the region. Sounding profiles support around 300 J/Kg of
CAPE, so a strike or two can`t be ruled out. Rain shower
activity will continue to increase through the night across the
north.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Pattern Overview: A 500mb trough and surface low pressure will
swing through the region over the weekend bringing widespread
rain Saturday, with shower activity lingering most of Sunday.
The system departs Sunday night with a ridge building in for the
first part of the week. Shower chances return midweek as a
trough swings through Wednesday along with the passage of a cold
front. Thursday looks dry behind the front.

Details: Saturday: Widespread rain will be ongoing Saturday
morning as low pressure passes through the region. There is some
spread in the ensemble QPF, with the Euro having more
widespread values of one inch. The GFS and Canadian keep these
amounts more isolated to the mountains and coast where upslope
and LLJ enhancement look likely. Outside of these areas ensemble
means are still in the range of 0.75" to near an inch, so this
will be a beneficial rain for everyone. The previously mentioned
LLJ axis looks like it will be mostly offshore, so while the
coast may see more rainfall than the interior this should
preclude any threat for flooding. Due to runoff the mountains
usually have a non-zero minor flood threat, and this fits with
the latest thinking from WPC where a Marginal ERO still exists.

Sunday and Monday: Low pressure slides offshore Sunday, but the
trend in this progression has been to slow it down, so shower
activity may linger through most of Sunday. At the least it will
be mostly cloudy with some breaks in the stratus heading toward
the evening hours. High temperatures will be limited to the 50s
south of the mountains, and mid to upper 40s to the north.
Skies clear overnight Sunday, but likely not quick enough for
radiational cooling to be a factor, so low temperatures look to
end up in the upper 30s and low 40s. Monday features clear skies
and flow turning southwesterly, beginning to usher in a warmer
airmass. High temperatures south of the mountains look to get
into the upper 60s and low 70s, with low to mid 60s to north.
Low temperatures bottom out in the 40s areawide.

Tuesday-Thursday: Established southwesterly flow makes Tuesday
the warmest day as 850mb temps exceed +10C. This translates to
mid- to upper 70s across much of the interior. The coast may end
up more in the mid 60s as flow turns onshore in the afternoon.
Clouds and shower chances will also be on the increase through
the evening ahead of an approaching front. Global models
currently keep the front and trough in the region Wednesday and
thusly shower chances during the day will stay as well. Shower
chances decrease overnight as the front and trough depart. This
should put us back in the clear for Thursday with a cooler
airmass.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Short Term...VFR through the day Friday with southern NH
terminals possibly diminishing to low MVFR/IFR toward end of
TAF valid time. Warm front lifting through in the afternoon/evening
will bring VFR showers most terminals.

Long Term...Widespread rain will bring about some MVFR
restrictions, with IFR restrictions possible in areas of heavier
rain, Saturday and Sunday. Ceilings trend back to VFR for
Monday and Tuesday. Tuesday night is the next chance for low
ceilings and showers to bring about restrictions. Thunderstorms
are possible at HIE and LEB with the passing of the front
Tuesday night.

&&

.MARINE...
Short Term...High pressure crests over the waters tonight and
moves to the east during the day tomorrow. Onshore southerly
flow increases through the day but seas and winds will remain
below SCA through tomorrow night.


Long Term...SCA conditions are likely Saturday as low pressure
slides over the waters ramping up southerly wind gusts and waves
to 6-8ft. Winds gusts taper off as winds shift around to
northerly for Sunday, but seas will take longer to fall below
SCA criteria. By Monday conditions should fall below SCA
criteria and stay below through Tuesday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$

SYNOPSIS...Dumont
NEAR TERM...Buster
SHORT TERM...Dumont
LONG TERM...Dumont
AVIATION...Buster
MARINE...Dumont