NWS Caribou, Maine Area Forecast Discussion
785
FXUS61 KCAR 230239
AFDCAR
Area Forecast Discussion
National Weather Service Caribou ME
939 PM EST Mon Dec 22 2025
.SYNOPSIS...
High pressure will ridge across the area overnight into
Tuesday. Low pressure will slide south of the region Tuesday
night into Wednesday. High pressure will return Wednesday night.
Weak low pressure will track northeast of the area on Thursday.
High pressure will then build over the area through Saturday.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
Update...
No change to any winter headlines. Surface high pressure will
build across the region overnight while an upper level
disturbance clips the region. Expect partly cloudy skies across
the forecast area overnight, with scattered flurries also
possible across the north and mountains. Low temperatures will
be dependent on cloud cover. Generally expect low temperatures
to range from around 5 below zero to around zero north, with
single digits to around 10 above Downeast. Have updated to
adjust for current conditions along with expected overnight
temperatures and clouds. Also, extended the ongoing Small Craft
Advisory through 1 AM.
Previous Discussion...
Key Message:
Snow is expected Tuesday night into Wednesday for all but far northeastern
Maine. The greatest accumulation will be from Coastal Hancock
County through southern Piscataquis County southwestward towards
central and southern Maine.
Discussion:
Tonight through Tuesday:
Clear skies early will give way to increasing clouds in the
afternoon on Tuesday with high temperatures slightly below
average, ranging from the mid teens across the north to upper
20s along the coast.
Tuesday Night:
A shortwave trough moving into southern New England will lead to
the development of an inverted surface trough along the Maine
coast Tuesday evening through Wednesday. Significant uncertainty
remains in its exact placement, with solutions ranging from the
GFS placement near Portland to the NAM placement just east of
Mount Desert Island. Given that inverted troughs are highly
mesoscale types of events, small shifts will significantly
change snow amounts. A blended placement of the inverted trough
near the Midcoast of Maine, similar to the ECMWF and RGEM, was
favored, and also aligns with studies of where inverted troughs
are climatologically most favored to be oriented along the Maine
coast. The gradient of snowfall in the Penobscot Bay area could
be significant, with potential for warning level snowfall
prompting a Winter Storm Watch for Coastal Hancock County.
Forecast soundings show more favorable lift within the dendritic
growth zone further inland, so snow to liquid ratios may reach
or exceed 20 to 1 over or northwest of Bangor into central and
southern Piscataquis County. Winter Weather Advisories have been
issued for these areas. Further east, QPF was lowered compared
to the NBM due to uncertainty in the inverted trough positioning
and potentially a sharper gradient in QPF than the NBM is
forecasting. Far northeastern portions of the forecast area may
see little to no accumulation.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
The storm discussed above tapers off Wednesday. A weak system
moves through from NW to SE Wednesday night and Thursday, with
the potential for light snow accumulation as much as an inch or
two, but also potentially just a dusting or less. Only have a
chance of snow in the forecast for now.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Key Message 1...Potential Significant Winter Storm Late Sunday/Monday
Key Message 2...Bitter Cold Thursday Night to Saturday
Key Message 1...
The main concern in the extended is the potential for a significant
winter storm late Sunday/Monday. There is unusually good model
agreement this far out for a system of at least decent strength
around this time. Most models/ensembles have a vigorous upper
trough moving through and rapidly strengthening a surface low
pressure that moves east through the region. Models generally
favor snow, but rain/snow or rain is possible especially
Downeast if some of the warmer solutions pan out. Bottom line is
this is still very far out and a lot can change, but we will
need to keep a close eye on this, as some model solutions have
heavy snow totals and significant winds.
Key Message 2...
The other lesser concern is a very cold airmass especially
Thursday night into Saturday. The cold air really moves in
Thursday night, with lows around zero in the north with
potential wind chills to around -20F. Not quite as cold
Downeast, but still cold. Pretty high confidence that it stays
cold Friday and Friday night, with highs Friday around 10 in
the north and 15-20 Downeast, and lows Friday night 10 below to
5 above, with the potential of some colder readings if we clear
out with high pressure moving in. Little/no precipitation
Thursday night through Saturday, with a weather system likely
missing us to the southwest as we will be too deep into the cold
air. Can`t rule out a little light snow getting as far NE as Bar
Harbor/Bangor/Greenville, but more than likely it`ll stay to our
SW.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: Expect VFR conditions overnight through much of
Tuesday across the region. However, MVFR/IFR conditions could
begin to develop at KBGR/KBHB later Tuesday afternoon with
developing snow. VFR/MVFR north Tuesday night with snow likely.
IFR/LIFR Downeast with snow. Variable winds 5 to 10 knots
tonight. Variable winds 5 to 10 knots, becoming east Tuesday.
East/northeast winds 10 to 15 knots Tuesday night.
SHORT TERM:
Wednesday...Potential IFR/MVFR Downeast early Wed, with
potential MVFR early Wed in the north, but confidence is low.
Most places should become VFR by Wed afternoon regardless. N
wind 5-10 kts.
Wednesday night-Thursday...VFR Downeast with possible MVFR, and
mainly MVFR Aroostook terminals in potential snow showers and
low cigs. Variable wind 5 kts becoming NW 10 kts.
Thursday night-Saturday...Mainly VFR. NW 5-15kts.
&&
.MARINE...
NEAR TERM: A Small Craft Advisory is in effect for much of the
waters, with the exception of the intra-coastal waters, through
1 AM. Winds/seas then below small craft advisory levels on all
the waters through the duration of the night and Tuesday. There
is a chance (slightly below 50 percent) of localized gales later
Tuesday night, but uncertainty remains on placement and timing
of the strongest winds. Light freezing spray overnight. A chance
of snow Tuesday afternoon. Snow and rain Tuesday night.
SHORT TERM: Potential NE gales Wed morning, but not enough
confidence to issue gale watch. Next chance of gales is Thursday
night, with potential freezing spray too.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory from 6 PM Tuesday to noon EST
Wednesday for MEZ010-015-016-031.
Winter Storm Watch from Tuesday evening through Wednesday
morning for MEZ029.
MARINE...Small Craft Advisory until 1 AM EST Tuesday for ANZ050-051.
&&
$$
Near Term...CN/MWS
Short Term...TF
Long Term...TF
Aviation...CN/TF
Marine...CN/MWS/TF
NWS CAR Office Area Forecast Discussion
