Derry, New Hampshire 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

715
FXUS61 KGYX 120736
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
336 AM EDT Thu Jun 12 2025

.SYNOPSIS...
Mostly dry, breezy, and warm weather is in store for today. A
stray shower will be possible in the mountains through the
afternoon however. Westerly wind gusts around 30 mph will
diminish this evening and a slightly cooler air mass will settle
over the region. In news that nobody wants to hear, the next
frontal boundary lifts into the region Saturday into Sunday and
will provide the focus for at least scattered showers.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Compact S/WV trof moving thru Quebec this morning will allow a
cold front to brush the north half of the forecast area. Some
scattered showers will skirt along the boundary in the
mtns...but the front is not expected to push all the way thru
the forecast area. To the south...west southwest winds will lead
to a warm day...with temps climbing into the 80s. It will also
be rather gusty thru the day...with 25 to 35 mph gusts at times.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
The trailing portion of the front will hang up over the forecast
area tonight. North of the boundary it will be cooler...but as
high pressure builds in it should allow for cooler readings
everywhere compared to this morning.

By Fri with more shallow mixing...temps will be a little cooler
than today. Readings are expected to be in the 70s south of the
mtns with 60s north.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
03Z Long Term Forecast Update... Little change in the latest
National Blend of Models forecast guidance. Showery weather
remains possible this weekend along with below normal
temperatures before a warming and drying trend begins early next
week.

Previously...
The 500 mb flow pattern will turn close to zonal across the northern
tier of the CONUS this weekend into early next week. At the surface,
high pressure will be centered south of Hudson Bay Friday through
the weekend with a west to east frontal zone setting up across the
Great Lakes and Northeast. Moisture from a weak wave crossing the
Ohio Valley will interact with this frontal zone this weekend
bringing chances for showers. Shower chances diminish Sunday into
Monday as high pressure slides over New England. High pressure then
shifts east through mid week leading to an upward trend in
temperatures and humidity.

High pressure centered south of Hudson Bay will extend into the
forecast area Friday providing fair weather. Light northwest flow
will prevail over the area except for a sea breeze developing along
the coast during the afternoon. Highs will range from the 60s north
to upper 70s across the south. High pressure holds over southeast
Canada Saturday while an open wave over the Ohio Valley advects warm
air and moisture northward. This set up will produce a west to east
baroclinic zone with waves of low pressure bringing chances for
showers Saturday into Sunday. Ensembles generally agree that shower
chances will be likely Saturday while amounts will be light with
mean QPF around 0.5 inches. Ensembles then suggest drier air will
work in from the north Sunday that will allow PoPs to decrease into
Sunday night. Mostly cloudy skies and east winds will keep things
cool over the weekend with highs mainly in the 60s.

High pressure slides southeast and crests over the region Monday for
a return to mostly fair weather. This high will then slide offshore
towards mid week with return flow advecting warmer air and moisture
into the region. With little in the way of surface features and
upper level support chances for showers will be low Tuesday into
Wednesday.

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
Short Term...Widespread VFR conditions expected thru Fri. A
passing front may lead to VCSH for HIE. West to west southwest
winds will be gusty south of the front...with surface gusts
around 25 kt expected today.

Long Term...Mainly VFR Friday into Friday night. More in the way of
clouds and -SHRA are likely Saturday into Sunday with periods of at
least MVFR possible. Drier air works into the region late Sunday
into Monday for a return to VFR.

&&

.MARINE...
Short Term...A front will brush the area this morning and lead
to a tightening pressure gradient this morning. A few gusts
around 25 kt are possible on the outer waters north of Cape
Elizabeth. Winds will remain gusty this afternoon but generally
stay below SCA thresholds.

Long Term...Winds and seas remain below SCA thresholds Friday into
early next week. Light offshore winds will turn onshore Friday. A
front stalling near the waters will bring periods of showers and
steady easterly flow over the weekend.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for ANZ150-
     152.

&&

$$

NEAR TERM...Legro
SHORT TERM...Legro
LONG TERM...Schroeter/Tubbs
AVIATION...Legro
MARINE...Legro