421
FXUS61 KGYX 300551
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
151 AM EDT Tue Sep 30 2025

.SYNOPSIS...
A cold front will continue to march south through the Northeast
on Tuesday, ushering in a cooler and drier air mass.
Temperatures on Wednesday and Thursday will stay in the 60s
during the day, and overnight widespread 20s and 30s are
forecast. Frost will be possible for many locations, even near
the coast. Starting Friday warmer conditions will return to the
area and winds become southwesterly once more. But much like
most of our discussions over the last few months, little rain is
in sight.

&&

.NEAR TERM /THROUGH TODAY/...
A cold front slides through by early morning, with high
pressure steadily building in through the daytime from the
north. The high brings with it a much drier airmass. Dew points
fall into the 30s today away from the coast, and RH values in
the 25-30 percent range. The cooler airmass will mostly be felt
across northern areas today, where highs in the 60s are
expected. South of the mountains, a downsloping northwesterly
breeze warms temps into the 70s for one more day.

High clouds from Tropical Storm Imelda near the Bahamas sink
southward through the morning, and will then mostly be confined
to near the Mass. border for the afternoon. Mainly sunny
conditions are expected elsewhere.

A building long period swell from Hurricane Humberto brings an
increasing rip current risk by this afternoon, especially along
the MidCoast.


&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
The cooler airmass becomes more noticeable tonight as a
northerly wind continues. Northern valleys likely decouple late
tonight, allowing temps to fall to right around freezing. Areas
of frost are likely in these areas, and frost headlines may be
needed for tonight. 30s are expected across much of the
interior, while more readings in the low to mid 40s are likely
along the coast.

High pressure continues to build southward through the day
tomorrow, bringing mostly sunny skies. The cooler airmass yields
more seasonable highs. Temps are likely to range from the mid
50s across the north, to the mid 60s along the coastline and
through southern New Hampshire. Dew points drop into the 30s to
upper 20s again tomorrow, but with cooler highs RH values won`t
be as low.

A long period swell continues to build from Humberto tomorrow.
Headlines will be handled one day at a time, but either a rip
current statement or high surf advisory will likely be needed
along the whole coastline tomorrow.


&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Key Message: Dry high pressure continues to dominate the
pattern. Along with above normal daytime temps...continued
deepening drought is anticipated.

Impacts: Lack of rain will likely expand drought thru this
period. In addition warm temps will exacerbate drying of surface
fuels and bring fire weather concerns back into the forecast.
Finally frost is possible both Wed and Thu nights over large
parts of the forecast area.

Forecast Details: A large area of high pressure will center
itself over the Northeast thru Thu/Fri before drifting offshore.
This high pressure will originate from central Canada and so
bring a cool and dry air mass with it. High temps will remain in
the 60s...though the breezy wind is expected to diminish by Thu
afternoon. More notable will be overnight temps...with both Wed
and Thu night possibly seeing 30s down to the coast. As such I
have patchy and areas of frost for most areas on both nights.

As the surface ridge axis slips south of the forecast area by
Fri...winds turn southwesterly again and warmer air surges
north. This will ensure our run of above normal temps continues.
High temps are forecast well into the 70s to near 80 for much
of the weekend with not much hope of rain either. Model guidance
hints at a couple of chance for a cold frontal passage similar
to the one dropping into the region tonight. But much like
tonight there is not much moisture to work with and showers will
be few and far between.

This means that the number one impact over the next 7 days will
be likely expansion of drought conditions again. Also the dry
air mass along with warming temps will likely bring minimum RH
values down into the 30 percent or lower range
again...increasing fire weather concerns.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Short Term...LIFR conditions in valley fog are likely at LEB
through mid morning today, and again late tonight. Valley fog is
possible at HIE late tonight. VFR prevails elsewhere through
tomorrow.


Long Term...Widespread VFR conditions into the weekend with high
pressure in control. Overnight ideal set up for radiation fog
will develop...and local IFR or lower conditions are likely for
valley locations. This will likely affect HIE and LEB.

&&

.MARINE...
Short Term...High pressure builds across the waters through
tomorrow. A building south-southeasterly swell from Hurricane
Humberto builds through tomorrow, with SCA conditions building
by this afternoon, and continuing through tomorrow.


Long Term...Winds and seas continue to diminish thru Thu...but
SCA conditions likely hang on until at least Thu morning outside
of the bays.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...High Risk for Rip Currents from 8 AM EDT Tuesday through Tuesday
     evening for MEZ024>027.
NH...None.
MARINE...Small Craft Advisory from 11 AM Tuesday to 8 PM EDT Wednesday
     for ANZ150-152-154.
     Small Craft Advisory from 8 AM to 8 PM EDT Wednesday for
     ANZ151-153.

&&

$$

NEAR TERM...Clair
SHORT TERM...Clair
LONG TERM...Legro
AVIATION...Clair/Legro
MARINE...Clair/Legro