179
FXUS61 KGYX 131153
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
652 AM EST Mon Jan 13 2025

.SYNOPSIS...
High pressure brings mostly dry conditions through much of
today, but another clipper system will bring chances for snow
this evening and tonight, mainly in the mountains, but there is
also a chance for light snow across portions of western Maine.
Upslope mountain snow showers continue Tuesday and Wednesday with
mostly dry and breezy conditions elsewhere. A brief shot of cold air
arrives Thursday with temperatures then moderating into the
weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
650 AM Update...Have increased cloud cover across NH with this
update based on upstream satellite trends. Will also need to
monitor the potential for snow showers entering NH toward
early evening as some guidance is suggested a few of these
could be heavy.

Skies are mostly cloudy this morning thanks to a shortwave
currently in the process of crossing overhead. There could be
flurries from time to time, except there is a somewhat better
chance for a light dusting of snow across far northern areas.
Latest observation support this with light snow being reported
just upstream in northern VT.

This wave will quickly move east of the area with decreasing
cloud cover in its wake from west to east through the morning
hours as shortwave ridging briefly builds in. Temperatures will
be nearly steady through daybreak, but those that do clear out will
likely drop a few degrees. The best chance of this will be southern
NH and maybe far SW ME, and latest satellite imagery is already
indicating thinning across southern NH.

Dry and partly sunny conditions are then expected for the
afternoon with light winds and highs again in the 30s. Another
wave out ahead of an upper low near the Great Lakes will
approach toward late afternoon or early evening, increasing
chances for snow showers across NH with the highest chances
being over the northern half of the state.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
Upper-level low continues to move eastward tonight, just north
of the International Border. Shortwave energy just out ahead of
it will keep chances of snow showers and light accumulations
toward the mountains this evening and then overnight as flow
turns to upslope. Models are also in pretty good agreement
developing a weak low somewhere near the western ME coastline
this evening into tonight, bringing a chance for light snow over
portions of western ME. In general amounts look limited to a
couple tenths of an inch. However, toward the Augusta and
Midcoast regions, models are hinting at more QPF (especially the
ECMWF), so it`s possible these areas may see upwards of an inch
of snow. So I have trended the forecast amounts a bit higher.

The weak low that brings the light snow across eastern areas will
exit to the east by or just after daybreak Tuesday. After a brief
period of partial clearing in the morning, expect increasing clouds
again by the afternoon with the area still under broad cyclonic flow
with upper-low to the north and steep low-level lapse rates. Upslope
showers continue in the mountains, possibly into the foothills in
the morning as well. Froude numbers then further increase indicating
flow will become unblocked by the afternoon, and I`m expecting this
to bring a few snow showers south of the mountains as another wave
approaches from the west. Winds look to get somewhat breezy to
around 25 mph, possibly closer to 30 mph in NH.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
1040 PM Update...New NBM is in and yields no large changes to
the local forecast. We expect a modest warmup through Saturday,
then colder with potential coastal storm?

Previously...

Winds increase and shift to the northwest Tuesday night
bringing upslope conditions and snow showers to the northern
mountains.

The relatively warm conditions on Tuesday will be replaced by
cold, Canadian air on brisk northwesterly winds by Wednesday.
The latest Bufkit files suggest at least 25kt+ winds will mix
down to the surface during this period. Temperatures will
struggle to climb through the teens in the north to the 20s in
the south. Have continued with high pops for the mountains
during this period.

A moderating trend will begin on Thursday ahead of a cold front
as it approaches from the west. This front will weaken
substantially by the time it reaches New England. 12Z models and
ensemble solutions suggest a ridge of high pressure will rebuild
over the region by Friday. This follows with a large scale
trough entering the Northeast with widespread precipitation over
the weekend.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
Short Term...VFR for most of today with light winds. Chances for
flight restrictions and snow showers increase late this afternoon
and evening for LEB and HIE...ceilings look primarily MVFR with IFR
vis possible. A period of light snow and MVFR ceilings could then
expand toward the western ME terminals tonight before
conditions likely bounce back to VFR by 12Z Tuesday. MVFR
ceilings and a chance of snow showers then persists at HIE
Tuesday with mostly VFR elsewhere. However, can`t rule out a
snow shower and brief restrictions south of the mountains.

Long Term...VFR will dominate the period south of the mountains. At
HIE, IFR/MVFR restrictions due to SHSN appear likely Tuesday
night through Thursday night.

&&

.MARINE...
Short Term...Light west to southwest flow keeps conditions under SCA
levels across the waters today. Westerly winds then increase this
evening and tonight as a weak low pressure forms somewhere near the
Maine coastline. This could bring a period of SCA conditions, mostly
across the southern waters tonight that possibly last into
Tuesday.

Long Term...SCA conditions likely in the Tuesday night through
Wednesday night given gusty northwest winds behind departing
low pressure. Weak ridges of high pressure before and after this
low will yield quiet conditions over the waters.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory from 10 PM this evening to 7 AM EST
     Tuesday for ANZ154.

&&

$$


NEAR TERM...Combs
SHORT TERM...Combs
LONG TERM...Cannon/Ekster