National Weather Service Forecast Discussion

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339
FXUS65 KBOU 252136
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
236 PM MST Thu Dec 25 2025

.KEY MESSAGES...

- Warm and dry for the plains Friday with elevated to near-
  critical fire weather conditions over the southern foothills,
  Denver metro, and Palmer Divide.

- The mountains will see snow beginning Friday night lasting
  through Sunday morning. The heaviest snow amounts will be in the
  Park and Gore Ranges with a Winter Storm Watch issued there.

- Lower elevations will see light snow Saturday night into Sunday
  morning. Much colder temperatures expected to accompany the
  snow.


&&

.DISCUSSION /Through Thursday/...
Issued at 145 PM MST Thu Dec 25 2025

A weak ridge aloft within the southwesterly flow will move over
Colorado on Friday. This will bring in drier air with slightly
cooler high temperatures. Some light snow showers are possible in
the Park Range mountains but the rest of the mountains and plains
should remain dry during the day.

The main concern on Friday will be elevated to near-critical fire
weather conditions. This is discussed further in the fire weather
section below.

A combination of a trough over the Southwest US and a trough
approaching from the Pacific Northwest will move towards Colorado
late Friday night. This will bring a wave of Pacific moisture to
the mountains of Colorado. Moderate to briefly heavy snow will
arrive after midnight in the Park and Gore Ranges. Snow will then
spread across most of the Colorado mountains late Friday night and
through the day on Saturday. Strong mid level frontogenesis will
move across northern Colorado Saturday evening through early
Sunday morning. Across the plains, there will be a cold front at
the surface will will push through around the same time dropping
temperatures quickly. Behind the front, northeast winds will
develop which will create upslope flow. All of these factors will
come together to create a couple bands of snow that will spread
across the area oriented from southwest to northeast. Ensemble
guidance has been consistent with regard to QPF across the plains
with roughly 0.15-0.20" across the northern Denver metro and
around 0.25" on the south side of the metro. With the light
upslope flow, 2-5" of snow is forecast for the western I-25
corridor and Palmer Divide while 1-4" of snow is forecast on the
east side of the I-25 corridor. Across the eastern plains, 0-2" of
snow is forecast. There will be moderate snow amounts in the
Front Range mountains and foothills. Some of the higher mountains
and ski areas may see close to a foot of snow. With the help from
the moderate to heavy snow late on Friday night, the Park and Gore
Ranges will see the highest snow amounts. Therefore, a Winter
Storm Watch was issued for forecast zone 31.

Cold temperatures are expected Sunday night with the fresh snow
and clear skies. Single digit lows are forecast across the plains
with the usual cold spots of Greeley and Limon potentially
getting close to 0 F.

Next work week will see dry conditions with temperatures
increasing. Highs will be above normal by Wednesday.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1205 PM MST Thu Dec 25 2025

Models have west to northwesterly winds at DIA this afternoon
then they transisition to normal drainage patterns by late
evening. More normal diurnal wind patterns are expected on
Friday. There will be no ceiling issues.

&&

.FIRE WEATHER...
Issued at 145 PM MST Thu Dec 25 2025

Drier air will move into the forecast area on Friday with relative
humidity dropping to 10% across the southern foothills, Denver
metro, and Palmer Divide. Gusty winds are expected over the higher
terrain with gusts up to 55 mph in the Front Range mountains. In
the foothills and adjacent plains, gusts could reach 35 mph. This
will lead to elevated to near-critical fire weather conditions
across the southern foothills, Denver metro, and Palmer Divide.
However, the highest wind gusts and lowest relative humidity are not
expected to overlap. Therefore, no fire weather highlights were
issued.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from late Friday night through late Saturday
night for COZ031.

&&

$$

DISCUSSION...Danielson
AVIATION...66
FIRE WEATHER...Danielson

NWS BOU Office Area Forecast Discussion