York, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

571
FXUS61 KGYX 201742
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1242 PM EST Sat Dec 20 2025

.SYNOPSIS...
An Alberta Clipper will track north of the area tonight and
Sunday, bringing a period of snow showers and a possible squall
from the mountains north. A cold airmass follows this system to
start the week. The next potential for accumulating snow arrives
Tuesday and Tuesday night before somewhat quieter and
seasonable weather returns for Christmas Eve and Christmas Day.

&&

.NEAR TERM /THROUGH TONIGHT/...

Key Messages:

- Increasing clouds with a period of snow showers from the
  mountains north after midnight.

Details: Early afternoon surface analysis reveals a potent low
pressure centered north of the Great Lakes with a narrow ridge axis
moving quickly east across New England.  The upstream low will pass
north of the region tonight...with top down saturation in the
presence of isentropic ascent bringing the potential for a few SHSN
to develop from the mountains north after midnight.  Any
accumulation through daybreak Sunday would be light...less than an
inch.

A southwesterly gradient will strengthen overhead through the night
with initially calm winds re-coupling and strengthening from the
southwest with gusts to 20 mph by daybreak Sunday.

The increasing cloudiness and mixing will lead to temperatures
rising overnight with evening lows in the lower-middle 20s warming
into the mid 20s to lower 30s from north to south.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...

Key Messages:

 - Potential for snow squalls from the mountains north Sunday
   morning associated with strong cold front.

 - Mild with highs above 40 along the coastal plain with
   afternoon temperatures falling and lows turning colder
   Sunday night with a few snow showers continuing in the
   mountains.

Details: Cold front crosses the forecast area from northwest to
southeast through the morning.  Mesoscale guidance has been
suggesting a band of heavier SHSN or snow squalls with the frontal
passage over the far north with SHSN activity diminishing further
south and east as llevel moisture becomes increasingly limited.
Across the north...llevel profiles intersect the DGZ with steep
llevel lapse rates and winds 40+kts at the top of the mixed
layer. These ingredients suggest squall potential and will
message this possibility in the afternoon Hazardous Weather
Outlook. Otherwise...the story of the day will be a shift to
gusty west northwest winds upon frontal passage with
temperatures across the north falling in the afternoon while
south of the mountains the warm previous night should allow
highs to push to at or near or above 40 with downslope
assistance.

Winds aloft strengthen Sunday night withe a new round of cold
advection keeping gusty winds ongoing through the night.  With T8s
nearing -20C towards daybreak Monday expect lows in the single
digits north to teens long the coast...with wind chills -5F to +5F
from north to south.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Key Messages:

* The long term period remains active with several shortwaves
  expected to move through region, bringing various chances of
  mainly light precipitation.
* Temperatures will generally be below to slightly below normal but
  a modest warmup will trend towards seasonable averages by the end
  of the week.

Forecast Details:

We start off the long term in northwest flow aloft and high pressure
at the surface. This will mean a cool Monday with highs forecast to
range from low to mid teens north, to the upper 20s and lower 30s
south. We could see end up seeing a few afternoon snow showers in
and around the mountains given upslope westerly flow, but most
locations will just see breezy and dry conditions.

The next weak shortwave approaches on Tuesday, flattening the ridge
to our west as it rides down. Medium to high chances (60 to 80
percent) for mainly light snow will spread from west to east
beginning on Tuesday morning and moving out of the area by the
night. As is usual, snow is likely to stick around in the mountains
for a while longer. By the time the snow moves out, many locations
will likely have seen at least a couple of inches of new snow which
may seal the deal for a White Christmas (highest totals look to be
across southern New Hampshire and southwest Maine at this time).

High pressure starts to nudge back in on Christmas Eve with only a
few mountain snow showers lingering through the first part of the
day. Ridging then starts to build back in by the evening and
overnight as conditions continue to look optimal for Santa`s journey
across New England.

On Christmas Day, a few models suggest a weak wave will move through
in the northwest flow aloft, possibly leading to some periodic light
snow. That being said, considerable uncertainty remains regarding
timing and location of any subtle feature so the NBM is painting
broad low chances (15 to 30 percent) for light snow over much of the
area. The ridge axis then crosses the forecast area Christmas night
and we eventually transition back into southwest flow aloft as the
next shortwave trough approaches which will be the driver of our
next widespread low to medium rain/snow chances (20 to 40 percent)
on Friday. While plenty can change this far out, this system looks
similar to many of the others in the long term with mainly light
precipitation and minimal impacts.

Regarding temperatures, we will see a modest warmup Tuesday through
the end of the week. Highs on Tuesday will range from the low to mid
20s north, to the low to mid 30s south. By Friday, the NBM has highs
ranging from the mid to upper 20s north, to the upper 30s and lower
40s south. Some guidance then has a slight cool down during the
weekend but NBM spread becomes large at the end of the week and into
the weekend which helps to illustrate pattern uncertainty.

&&

.AVIATION /18Z SATURDAY THROUGH WEDNESDAY/...
Short Term...

Summary: Low pressure passes north of the region tonight with
increasing clouds and some mountain snow showers with a few squalls
possible HIE and points north on Sunday morning.  otherwise...gusty
southwest winds tonight turn northwest Sunday and remain gusty
through Sunday night

Restrictions: VFR conditions dominate outside of HIE through the TAF
period.  Here...SHSN potential increases after midnight tonight
through Sunday morning with isolated/scattered MVFR/IFR
restrictions.  Cloudiness will continue at HIE through the remainder
of the TAF period but CIGS are expected to remain VFR.

Winds: Winds quickly diminishing attm...westerly 5-10kts.  These
will shift southwest tonight 5-10kts /except 10-15kts coastal sites/
before shifting westerly and increasing to 15g25-30kts for Sunday
and Sunday night.

LLWS:  2kft south-southwesterly winds increase to 40-45kts tonight
with a period of LLWS through Sunday morning with LLWS ending as the
cold front passes through the region during the morning.

Long Term...VFR conditions are expected Monday, with another system
possibly bringing more restrictions Tuesday that may last into the
first part of Wednesday. Otherwise, upsloping could bring MVFR
ceilings and snow showers at HIE the rest of the day Wednesday.

&&

.MARINE...
Short Term...Southwesterly winds strengthen to gale force
tonight as low pressure passes well north of the waters. Winds
shift northwesterly late Sunday with gale force gusts continuing
across the outer water through Sunday night. For this
reason...have transitioned gale watch to warning...and in collab
with BOX/CAR extended the end time of the warning to 12Z for
the outer waters.

Long Term...Marginal northwest gales may linger into Monday morning,
and this will be followed by another period of at least SCA
conditions Tuesday into Tuesday night as the next clipper crosses
the waters. Conditions then improve Wednesday through Wednesday
night as high pressure builds across the region. High pressure
shifts east late in the week as another front approaches.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Gale Warning from 10 PM this evening to 7 AM EST Monday for
     ANZ150-152-154.
     Gale Warning from 10 PM this evening to 7 PM EST Sunday for
     ANZ151-153.

&&

$$

NEAR TERM...Arnott
SHORT TERM...Arnott
LONG TERM...Hargrove
AVIATION...Arnott/Hargrove
MARINE...Arnott/Hargrove