December 2025 Climate Summary for Northern and Eastern Maine
...DECEMBER 2025 CLIMATE NARRATIVE FOR NORTHERN/EASTERN MAINE...
The December 2025 season was below climatological normal for daily
maximum, minimum, and average daily temperatures. Around, to
slightly below, average precipitation fell at all climate sites. In
terms of snowfall, however, there was more snow than normal at
Bangor, but below normal snowfall for Caribou. Drought conditions
persisted, as frost depth continued to increase this month. That
being said, portions of Washington county did have some drought
conditions improve by the end of the month.
Persistent drought continued into December in northern and central
Maine. The ground was frozen the entire month in northern counties,
continuing to restrict any moisture from penetrating down into the
soil. Frost depth at the beginning of December was 2 inches at the
Caribou office, gradually diminishing down to a low depth of 1 inch
during a warm up period around December 19th, but rounded the month
out to a frost depth of 12 inches. All climate sites recorded
around, or slightly below, average precipitation. Houlton had the
largest deficit, receiving only 2.56 inches of precipitation, which
is 0.81 inches below climatological normal for December. Caribou
received 2.88 inches of precipitation, which is 0.72 inches below
normal. Bangor and Millinocket were close to average, with Bangor
receiving 3.61 inches of precipitation, and Millinocket receiving
3.41 inches of precipitation, a 0.11 and 0.04 inch deficit
respectively.
At the end of November, northern Somerset, northwestern and central
Aroostook, northern Piscataquis, southern Penobscot, and portions of
Hancock and Washington counties, were included in severe drought.
The Central Highlands region, southern Aroostook, and portions of
far northern Hancock and Washington counties were in moderate
drought. There was some slight improvement by the end of the month
for Washington county, as Downeast ground remained unfrozen, and
snow/rainfall events at the end of the month provided some moisture,
resulting in the county improving from severe drought to moderate
drought. Otherwise, the rest of the state was left in the status
quo. In terms of rivers, all rivers in the region saw river ice
rapidly thicken. Southern rivers had a brief period of ice break up
during the mid-December warm up event, but quickly refroze later in
the month as temperatures fell below freezing once again.
In terms of snowfall, Bangor had an above average December,
recording 19.8 inches of snow, which is 5.1 inches above normal for
December. Caribou only received 24.0 inches of snow, which is
roughly 1.2 inches below average for December. There were multiple
snowstorms in December throughout northern and eastern Maine as
well, adding enough snow to provide a snow pack deep enough to begin
the ski and snowmobiling season, primarily in the north and central
region. One such snowstorm event occurred December 2nd, dropping 2-4
inches of snow in the north, and 7-9 inches of snow in
northern/central Washington county. On December 10th - 11th, 8-10
inches of snow fell in eastern Aroostook, 6-8 inches in the rest of
the northern region, and 1-3 inches Downeast. Two snow squalls were
observed on December 21st, one in Piscataquis county, and the other
in Aroostook county, both of which significantly reduced visibility
and significant wind gusts. December 23-24th, another snow storm
produced roughly 6-9 inches of snow in southern Piscataquis, western
Penobscot, and western Hancock counties. Lastly, a nasty mixed
precipitation event rounded out the end of 2025, dumping about 7-10
inches of snow in the Crown of Maine and North Woods regions, along
with around 4 inches in the north. Areas got up to an inch of sleet
in the north, as well as ½ an inch of freezing rain ice
accumulation. This storm led to poor road conditions and multiple
car accidents. At the end of the month, Bangor ended up recording a
4 inch snow depth, and Caribou a 6 inch snow depth.
Another significant weather event that occurred in December, was a
high wind event that resulted in multiple power outages, downed
trees, and road closures, primarily in Downeast Maine. Highest wind
gusts were in Penobscot county, with a 67 mph gusts recorded in
Millinocket.
Temperatures were well below normal at all climate sites, with
average temperatures generally 5 to 7 degrees below climatological
normal. Monthly maximum temperatures were below average for
December, generally 5.0 degrees below climatological normal. Bangor
had the coldest daytime highs, 5.3 degrees below normal. Millinocket
average high temperatures were 5.0 degrees below normal. Caribou was
4.9 degrees below normal. Lastly, Houlton daily high temperatures
were 4.8 degrees below climatological normal. The warmest day was
December 19th, which broke multiple records for the daytime high in
Bangor, Millinocket, and Houlton, with temperatures rising into the
mid-50s ahead of a warm front.
Monthly minimum temperatures were generally 6 to 7 degrees below
climatological normal for all climate sites. Bangor and Houlton had
the coldest overnight lows, both being 7.4 degrees below normal.
Caribou had minimum temperature values roughly 6.3 degrees below
climatological normal. Millinocket low temperatures were 5.9 degrees
below normal. There was a significant cold spell December 4th-5th,
with wind chill values reaching down into the -25 to -30 range in
northern Aroostook county. Values -15 to -20 were recorded Downeast.
This December was the coldest December for all four climate sites
since 2017.
For the month ahead, Climate Prediction Center (CPC) is showing a
probability of below normal temperatures for the entire state of
Maine. There is no strong signal for precipitation. For the next
three months, there is no strong signal for above or below normal
temperatures or precipitation in Maine. CPC currently has a La Nina
Advisory issued, where the United States can expect La Nina
conditions to persist, before transitioning to ENSO-neutral in early
2026.
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ASB
