National Weather Service Forecast Discussion

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694
FXUS65 KBOU 240532
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1032 PM MST Mon Feb 23 2026

.KEY MESSAGES...

- Another big warm-up for the upcoming work week.

- Strong winds expected along the east slopes of the Front Range
  Mountains and foothills on Tuesday.

- Snow chances return to the mountains Tuesday night.

- Elevated to critical fire weather conditions possible across
  the plains through the week (Friday).

&&

.DISCUSSION /Through Monday/...
Issued at 120 PM MST Mon Feb 23 2026

Strong upper level high will remain centered over the southwest
part of the country and Baja Mexico through at least Saturday.
Colorado will be on the periphery of the ridge. We`ll see the warm
and mostly dry conditions under this pattern. However, strong
northwest flow aloft will be over or just north of Colorado
bringing breezy to windy conditions at times, especially to
northern Colorado.

For tonight and Tuesday, flow aloft increases as the jet sinks
south and nears Colorado. Winds increase along the east slopes of
the Front Range mountains and foothills tonight, likely becoming
strong Tuesday morning. Ridgetop winds increase to 50 to 60 knots
by Tuesday morning. Models in good agreement with some mountain
wave amplification of theses winds down to about 7000 feet MSL
with gusts to 80 mph possible. This is not a classic mountain wave
set up for the lower foothills and adjacent plains. There is
little to no ridge top stable layer and strong mid to upper level
winds, which tends to sheer the mountain wave. For the adjacent
plains, channels/fingers of gusty winds to 45 mph will be possible
Tuesday. This combined with warm temperatures and relative
humidities in the teens will lead to elevated to critical fire
weather conditions. (See Fire Weather Discussion below).

The jet continues to slowly sink southward Tuesday night and
Wednesday. This will help to increase Pacific moisture and provide
lift for snow over the mountains. Mountain snow is expected to
increase over the mountains Wednesday as a shortwave trough
embedded in the northwest flow nears Colorado. Snowfall amounts
Tuesday night through Wednesday night looks to be 6 to 12 inches
for most of the mountains (Advisories issued) and up to 16 inches
for the Park and Gore ranges (Warning issued). For the lower
elevations Wednesday, warm and windy conditions are expected with
wind gusts up to 55 mph. Moisture slowly increases ahead of the
shortwave trough Wednesday, helping to keep relative humidities
above 20 percent. May be enough lift and moisture for a few weak
showers over the eastern plains. A weak cold front (more so a wind
shift) pushes south through eastern Colorado during the early
evening hours, possibly bringing a few showers to the Palmer
Divide, southern foothills, and Denver metro area. Any
precipitation is expected to be light. The front and eventual
subsidence behind the shortwave is expected to produce windy
conditions through at least Wednesday evening.

For Thursday and Friday, strong northwest flow aloft continues
with the jet stream overhead. Expect warm and dry conditions to
persist under this pattern. Windy conditions and elevated to
critical fire weather conditions will continue to be the main
weather concern.

On Saturday, the jet reorganizes over the Northern Plains,
bringing less wind and decreasing the fire weather threat. Models
showing a cold front pushing south through the area sometime
Saturday. Could be morning, afternoon, or evening. This will lead
to cooler temperatures possibly for Saturday but more likely for
Sunday.

The upper level ridge finally begins to shift eastward Sunday and
Monday. Another jet streak will be possible during this time
frame, possibly bring snow to the mountains with a chance for
light rain over the plains. Temperatures decrease a little, but
remain above normal for this time of year.

&&

.AVIATION /06Z TAFS through 06Z Wednesday/...
Issued at 1030 PM MST Mon Feb 23 2026

VFR through the TAF period. Drainage winds are likely to prevail
overnight tonight. Can`t rule out a brief westerly puff of wind at
BJC but otherwise quiet conditions are expected. We should see a
transition to gustier WNW winds as early as 18z Tuesday as deeper
mixing develops. Boundary layer mean wind profiles would suggest
generally 20-25KT gusts during the afternoon, which is largely
supported by deterministic output and some statistical guidance.
The best chance of a >30kt gust would be at BJC. Winds should
diminish after 00z with a return to drainage by late Tuesday
evening.

&&

.FIRE WEATHER...
Issued at 120 PM MST Mon Feb 23 2026

Red Flag Warnings were issued for the foothills and adjacent
plains for Tuesday. Winds for the foothills down to about 7000
feet are expected to be strong with gusts to 80 mph. Even though
relative humidities don`t fall into the lower to mid teens here,
upper teens and lower 20s will result in critical fire weather
conditions. On the plains, channels of stronger winds to 45 mph
are expected from Fort Collins and southward. Some locations may
not see the stronger winds (possibly light east winds). However,
given some areas may see wind gusts well above the 25 mph
threshold with relative humidities down to 10 percent, opted to
hoist a widespread Red Flag Warning.

On Wednesday, widespread windy conditions are expected with gusts
to 55 mph. An approaching storm system will increase low level
moisture possibly leading to a few weak showers over the plains.
With relative humidities expected to stay above 20 percent decided
not to issue a Red Flag Warning.

The warm, dry, and possibly windy pattern continues for Thursday
and Friday. Location of the stronger winds is still uncertain.
Models generally favor northern Colorado and northward. A slight
shift north would take the stronger winds out of Colorado, while a
southward shift would bring widespread windy conditions both
days.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 8 PM Tuesday to midnight MST Wednesday
night for COZ031.

High Wind Warning from 8 AM to 6 PM MST Tuesday for COZ033>035.

Winter Weather Advisory from 8 PM Tuesday to midnight MST
Wednesday night for COZ033-034.

Red Flag Warning from 10 AM to 5 PM MST Tuesday for COZ215-216-
238>240-242-243.

&&

$$

DISCUSSION...12
AVIATION...Hiris
FIRE WEATHER...12

NWS BOU Office Area Forecast Discussion