535
FXUS61 KGYX 121419
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
919 AM EST Wed Feb 12 2025

.SYNOPSIS...
An active winter pattern continues this week through the
weekend. High pressure allows for dry weather through
today. An area of low pressure moves across the Northeast
tonight and Thursday bringing a period of accumulating snow
followed by a wintry mix. Blustery conditions follow for Friday
in the wake of this system. Low pressure tracks across the Ohio
Valley and the Northeast over the weekend bringing another
round of accumulating snow that could transition to a wintry mix
Sunday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

915 AM Update...Mostly clear skies are present over the region.
Today will feature mostly tranquil weather as high pressure
builds in for the day. No meaningful changes were made in this
update, but temperatures were updated through the day to
reflect most recent observations and trends.


610 AM Update...Little adjustments to the going forecast early
this morning other than to update temperatures and clouds based
on latest observational data.

Previously...

Fair weather today with partly sunny skies and temperatures
mainly in the 20s as high pressure ridging remains overhead.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Low pressure approaches from the southwest tonight, with forcing
for ascent sufficient for snow to break out from southwest to
northeast overnight. Most locations should be snowing, at least
lightly by 12z Thursday. This will make the morning commute
slick in most if not all zones. The first inch or two of snow
in events is largely responsible for driving
issues/accidents/slide-offs. Have therefore decided to issue a
winter weather advisory for most forecast zones as the morning
commute is expected to be slippery, especially with cold road
surfaces continuing, even if advisory level snow amounts aren`t
technically met in many areas.

As Thursday morning progresses low and mid level warming is
expected to take place which should aid in precip types to turn
to rain in the far south and immediate coast. Just north and
west, a period of light sleet and freezing rain is expected,
further bolstering a need for an advisory into the early
afternoon hours even though sleet and fzra on top of snow and
treated roadways isn`t nearly as bad as icing is on bare
surfaces.

A southeasterly LLJ will contribute to downsloping on the
westerly slopes of the Whites and portions of the CT River
Valley so no advisory there at this time. However, downsloping
winds could be quite gusty tonight, with up to 45 MPH possible
in places such as KHIE.

Overall, a relatively light and quick moving event, but enough
wintry precip to make travel messy.

The precipitation will wind down quickly from southwest to
northeast during the afternoon (early evening north) as a cold
front sweeps on through. Winds could get quite gusty Thursday
evening with some guidance suggesting the need for a short term
wind advisory for southern zones.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Overview: The active winter pattern will continue through the
long term period. Thursday night and Friday will be blustery in
the wake of the Thursday system. High pressure slides west to
east across the area late Friday through Saturday morning for a
period of dry conditions and slackening winds. High pressure
moves east of the area Saturday with warm air advection leading
to snow breaking out over the area by Saturday afternoon. All
the while, an area of low pressure will be taking shape over the
lower Mississippi Valley. This area of low pressure will track
northeastward along the spine of the Appalachians Saturday night
and across New England on Sunday allowing for precipitation to
continue Saturday night through Sunday night. Models are in good
agreement that system will contain more moisture than previous
systems. Temperatures will likely allow for accumulating snow
late Saturday into Sunday morning with a snow/mix/rain line
encroaching northward depending on the track of the surface
low. This system exits Monday with another Arctic airmass poised
to drop into the the area.

Impacts:
*Gusty winds Thursday night into Friday may approach Wind Advisory
criteria.

*Several inches of accumulating snowfall late Saturday into
Sunday morning will make for difficult travel. Precipitation
may change to a wintry mix south to north Sunday while the
mountains and north continue to see accumulating snow. This will
continue travel impacts into Sunday evening.

Details: Low pressure will deepen in the Canadian Maritimes Thursday
night strengthening the PGF over the area as high pressure builds in
from the west. Outside of the mountains, NW winds will gust 30-40
mph with gusts in the mountains in excess of 50 mph. Otherwise it
will be a mostly dry day with highs ranging from the teens north to
upper 20s south. High pressure slides overhead Friday night allowing
winds to slacken and lows dropping into the single digits below
zero north and above zero south.

An upper trough will move into the West Coast Thursday and will be
the primary feature giving rise to a potent area of low pressure
impacting the region Saturday night and Sunday. Before this system
reaches New England, a period of warm air advection around the
departing high will lead to snow breaking out by Saturday afternoon.
Snow will likely continue Saturday night into Sunday morning. While
models are in good agreement on the timing of this system, there is
variance in the track of the low and the northward extent of a
snow/mix/rain line Sunday. The ECMWF/EPS is the more amplified
solution with the upper trough going negative tilt and the
surface low taking a more inland track. These solutions result
in the mix/rain line pushing well inland. The GFS/GEFS is less
amplified with the surface low tracking along the coast with the
mix line restricted to the coastal plain. At this time range,
and since the parent system is still well out in the Pacific, it
will likely take a few days to iron out the details of p-types
and amounts. However, ensembles do show mean QPF around 1.0 to
1.5 inches, so this system will bear watching as this much QPF
will bring the potential for Warning level snowfall.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
Short Term...VFR expected today with high pressure overhead. Low
pressure moves in from the southwest tonight with snow.
Conditions deteriorate across southern NH by late evening, then
spread to MVFR then IFR to the rest of the area by about 12z
Thu as lopres system moves across the region, bringing snow,
sleet, freezing rain and rain.

Long Term...Conditions improve Thursday night into Friday, while
it will be gusty with NW winds gusting 30-35 kts. VFR is likely
Friday into Saturday morning. Snow breaks out Saturday with
IFR/LIFR likely Saturday night and Sunday.

&&

.MARINE...
Short Term...Low pressure will affect the waters tonight and
Thursday. SCA conditions are expected tonight across southern
waters, with gales off the midcoast and Pen Bay. Winds will
subside for a time Thu evening but likely be brief.

Long Term...Gales may be needed Thursday night and Friday as NW
winds increase in the wake of low pressure moving into the
Canadian Maritimes. Winds and seas drop below SCA thresholds
Friday night into Saturday before another low pressure
approaches Saturday night into Sunday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory from 3 AM to 6 PM EST Thursday for
     MEZ007>009-012>014-033.
     Winter Weather Advisory from midnight tonight to 3 PM EST
     Thursday for MEZ018>022-025>028.
     Winter Weather Advisory from 10 PM this evening to noon EST
     Thursday for MEZ023-024.
NH...Winter Weather Advisory from 3 AM to 6 PM EST Thursday for
     NHZ004>006.
     Winter Weather Advisory from 10 PM this evening to noon EST
     Thursday for NHZ007>015.
MARINE...Gale Warning from 7 AM to 4 PM EST Thursday for ANZ150>152.
     Small Craft Advisory from midnight tonight to 7 PM EST
     Thursday for ANZ153-154.

&&

$$


NEAR TERM...Ekster/Palmer
SHORT TERM...Ekster
LONG TERM...Legro/Schroeter