NWS Gray, Maine Area Forecast Discussion
291
FXUS61 KGYX 181920
AFDGYX
Area Forecast Discussion
National Weather Service Gray ME
220 PM EST Sun Jan 18 2026
.WHAT HAS CHANGED...
Lower snow amounts are expected for portions of the Maine
Midcoast and southern Kennebec Valley. The bulk of accumulating
snow is now expected this evening through tonight. There will
be another round of snow that moves northward through the
forecast area Monday morning.
&&
.KEY MESSAGES...
1. Accumulating snow begins late this afternoon for southern New
Hampshire, pushing north into coastal and interior Maine
tonight. Another round of snow is likely for the Monday morning
commute. Drivers should allow extra time for travel overnight
and Monday morning.
2. An extended stretch of below normal temperatures begins
Tuesday with ambient or feels like temperatures near or below
zero through the majority of the week.
3. The next chance for accumulating snow may come midweek with
slick travel possible for the Thursday morning commute.
&&
.DISCUSSION...
KEY MESSAGE 1 DESCRIPTION...
Impressive WV presentation this afternoon as a baroclinic leaf
orients itself along the US East Coast. Low pressure will
organize off the Mid Atlantic coast this evening, progressing
northeast outside of the Gulf of Maine.
As a result, accumulating snow is expected this evening and
overnight for the coast, interior, and central/southern New
Hampshire. However, forecast snow amounts have decreased for
zones away from the coast in southern Maine. Morning guidance
trends have continued to decrease QPF amounts further inland,
with the axis of greatest QPF now aligned along the coast and
into southern NH (where snow totals have varied little since
last night). The ongoing Winter Weather Advisory will continue,
but has been split between two segments to communicate these
changes in snow amounts. 3 to 6 inches of snow is still forecast
for southern NH and York County, ME...with 2 to 4 inches of snow
northeast up the ME coast and interior. While snowfall criteria
may not be met for a portion of this area, impacts Monday
morning will still be slick.
There will be two distinctive rounds over the next 24 hours. The
first will deliver the most snow to the region overnight. Snow
begins this evening, with snowfall rates greatest across
southern NH between 8pm and 1 am. Its here that organized lift
bisects the DGZ for a period to allow good flake growth and
quicker accumulations. This pivots north, but moves off the
Maine coast late tonight, missing the ME Midcoast out to sea.
The second round is expected to be lighter, but bring continuing
snow for the Monday morning commute. This looks to be a weak
low pres or an inverted trough developing in the Gulf of Maine
Monday morning. Cyclogenesis could also be spurred on as a
secondary low development from low pres approaching from the
Great Lakes. While portions of Maine see a break or weakening
snow late tonight, organization of this disturbance could
continue snow in NH much of the night through to Monday
afternoon. This snow then lifts north as the morning progresses,
with an additional 1 to 2 inches. Should this feature slow,
could see a time extension in the Winter Weather Advisory
possible.
KEY MESSAGE 2 DESCRIPTION...
High pressure begins to build in to the area Tuesday making for
a dry day, but this also coincides with an arctic airmass
entering the region. 850 mb temperatures plummet to around -20C
by the afternoon, leaving high temperatures topped out in the
upper teens to low 20s south of the mountains and in the low to
mid-teens in the north. It is going to feel even colder as a
tight pressure gradient supports wind gusts of 20-25 mph. This
makes it feel more like single digits in the south and single
digits below zero in the north. A shortwave crossing the area
adds some clouds to the mix for the afternoon and evening, but
heights continue to rise over the the region and clear skies by
nightfall. This combined with fresh snow and calming winds
should make for a very cold night. I blended in some of the 10th
percentile NBM to account for what should be solid radiational
cooling resulting in low temperatures bottoming out in the low
single digits from the foothills southward and in the low single
digits below zero. The pressure gradient looks to relax quite a
bit by this point, but enough a breeze remains to add a
windchill factor that pushes the entire area below zero.
850 mb temperatures warm midweek as an approaching shortwave
turns flow southwesterly, but once it passes arctic air will
once again be able to enter the region with very cold
temperatures possible again toward the end of the week.
KEY MESSAGE 3 DESCRIPTION...
A shortwave trough approaches the region Wednesday night with
low pressure passing to our north, dragging a cold front into
the area. All this lift through the column would be enough to
support snow with cold air already in place. Ensembles are in
fairly good agreement on this low track, but do have some subtle
timing differences with the GEFS lagging slightly behind the
Euro Ensemble. The other thing Ensembles are in good agreement
on is QPF around a tenth of an inch, which with temperatures
expected to be in the teens may result in accumulations over an
inch on account of the likely higher snow ratios. Even with the
subtle timing differences it looks like a slippery Thursday
morning commute is in the cards if this occurs.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Through 18z Monday...VFR conditions through 00z, but ceilings
continue to lower, especially for southern NH. MVFR/IFR trend
expected quickly this evening as SN begins south to north. Vis
impacts greatest for southern NH terminals where snow rates
will be heaviest...1/2SM possible between 1z-6z. ME terminals
along the coast will see largest vis impact due to SN. Light
snow continues for the forecast area into Monday morning where
snow will life across the area with additional period of lower
vis. This begins to exit northeast after 18z, with VFR trend
into Mon evening.
Outlook
Monday Night: Ocnl SN remains for HIE into the overnight
hours, otherwise VFR with gusty WSW winds 15 to 20 kts.
Tuesday: VFR prevails at all terminals. Westerly wind gusts
20-25 kts possible in the afternoon.
Tuesday Night: VFR prevails at all terminals.
Wednesday: Ceilings lower through the day, with most terminals
MVFR by the evening.
Wednesday Night-Thursday: MVFR prevails with light snow showers
possible. IFR restrictions possible at terminals that see these
showers move overhead.
Thursday Night: Ceilings improve to VFR at all terminals.
Friday: VFR prevails at all terminals.
&&
.MARINE...
SCA conditions continue tonight with a brief lull in criteria
possible late tonight. Winds then increase Monday morning as low
pressure exits to the northeast and another weak low develops
over the Gulf of Maine. Winds will then increase Monday evening
towards Gale force into Tuesday.
Potential westerly gales taper off Tuesday night with SCA wind
gusts tapering off later Wednesday morning bringing an end to
freezing spray as well. Wind gusts and seas ramp right back up
Wednesday night as a front approaches and crosses the waters.
This may necessitate just leaving SCAs in place. With that being
said SCAs may be needed through the end of the week as strong
winds return late week, with freezing spray returning as well.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory until 1 PM EST Monday for MEZ018>028.
NH...Winter Weather Advisory until 1 PM EST Monday for NHZ010>015.
MARINE...Small Craft Advisory until 7 AM EST Monday for ANZ150-152.
Gale Watch from Monday evening through late Tuesday night for
ANZ150-152-154.
&&
$$
DISCUSSION...Baron/Cornwell
NWS GYX Office Area Forecast Discussion
