Area Forecast Discussion
Issued by NWS Portland, ME

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129
FXUS61 KGYX 090542
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1242 AM EST Tue Dec 9 2025

.SYNOPSIS...
Cold conditions continue today under high pressure. A weak
system brings a period of light snow tonight. Low pressure
tracks across northern New England Wednesday, spreading
accumulating snow across the interior while areas near the coast
will see mostly rain. A cold front cross Thursday morning for
drier and blustery conditions lasting into Friday.

&&

.NEAR TERM /TODAY/...
A frigid start to the day will give way to yet another below
normal temp day. Highs once again are not expected to make it
out of the 20s for the vast majority of the forecast area.
Plenty of early day sun and lighter winds will make it more
tolerable than yesterday however.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
Increasing clouds are expected around sunset as a warm front
lifts into the forecasts area. The departing cold air mass will
allow some ocean effect precip to concentrate on the Midcoast
with predominately southwest winds overnight. An inch or two of
snow is possible from Casco Bay north by the time it all shifts
Downeast.

But a stronger storm and more widespread precip is expected for
Wed. A seasonably strong low pressure will move out of the
Great Lakes and track thru or just north of the forecast area.
Current forecast soundings show a quite warm boundary layer for
areas near the coast...with above freezing air around 2000 ft
deep. I prefer to see it half as deep in order to get snow to
reach the ground with marginal temps. Overall the forecast has
much of southern NH as rain...as well as coastal western Maine.
This is based off the NBM mean forecast...but the 50th
percentile is even warmer. So there are likely some very warm
members in the blend. Still the foothills into the mtns will see
several inches of accumulation before precip moves out. This
snow may affect the evening commute and lead to some hazardous
travel...especially for those returning from the rainier
southern parts of the states.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Low pressure will track through the St Lawrence Valley
Wednesday night and will drag a cold front through the area
Thursday morning. Steady precipitation ends Wednesday night with
upslope snow showers lingering in the mountains through
Thursday. The polar jet stream will be oriented from British
Columbia towards the Mid Atlantic into the weekend directing
additional disturbances near the Northeast. A multi model
consensus keeps the bulk of moisture from these disturbances
south of the forecast area. Temperatures will run below normal
through the long term with highs struggling to get out of the
20s again early next week.

Incoming 00Z guidance is in general agreement that a surface
low will track from near Montreal across northern Maine from 00Z
to 06Z Thursday. Steady precipitation associated with WAA with
taper off during this time as dry air works into the system
within the H5 to H7 layer. Temperatures will drop below freezing
overnight changing any rain back to snow while any additional
accumulations outside the mountains will be less than an inch.
Winds will shift out of the west to northwest Thursday as a cold
front crosses with gusts to around 25 mph by Thursday
afternoon. Colder air lags behind the front and with the help of
downsloping temperatures reach the upper 30s along the coast
with highs ranging from the 20s to low 30s north south
elsewhere.

Short wave ridging builds in Friday for mostly fair weather
with highs ranging from the teens north to near 30 degrees along
the coast. Additional pieces of vorticity/short waves rotate
through a deepening long wave trough over the Northeast through
the weekend while models keep moisture south of the forecast
area. The going forecast calls for isolated snow showers
Saturday and Sunday with high pressure building in Monday.

&&

.AVIATION /04Z TODAY THROUGH SATURDAY/...
Short Term...VFR conditions today will give way to areas of
MVFR CIGs in ocean effect cloud cover across western Maine
tonight. Local IFR or lower conditions are possible in any snow
showers that move onshore. This threat will include both AUG and
RKD. More widespread precipitation arrives Wed...with areas of
IFR or lower conditions expected across most of the forecast
area. Precip may start as snow for all terminals...but is
expected to change to rain for coastal sites. The greatest
uncertainty will be at CON and AUG where snow may hang on longer
than modeled.

Long Term...Precipitation tapers off Wednesday night while low
cigs likely bring at least MVFR conditions. Cigs likely scatter
Thursday morning south of the mountains. Upslope clouds and
-SHSN will linger at KHIE through Thursday. Mainly VFR Friday
into Saturday.

&&

.MARINE...
Short Term...A warm front will lift across the waters tonight
and southwest winds will increase behind it. Outside the bays
SCA conditions are likely for a brief period. As the cold air
mass retreats there may be some ocean effect snow
showers...especially on the waters north of Cape Elizabeth.
These may briefly reduce visibility to less than one half mile
at times. Another strong storm and stronger accompanying low
level winds arrive Wed. There may be a better chance for some
low end gale force gusts well outside the bays...but otherwise
SCA conditions continue.

Long Term...Winds shift offshore in the wake of a cold front
Thursday and will gust in excess of 30 kts through Friday. Winds
and seas drop below SCA thresholds Friday night into Saturday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory from 7 PM Tuesday to 7 AM EST Wednesday
     for ANZ150-152-154.

&&

$$

NEAR TERM...Legro
SHORT TERM...Legro
LONG TERM...Schroeter