National Weather Service Forecast Discussion

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081
FXUS65 KBOU 230713
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1213 AM MST Mon Feb 23 2026

.KEY MESSAGES...

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

- Strong winds expected along the Front Range and foothills on
  Tuesday.

- Snow chances return to the mountains mid-week.

- Potential for multiple days of elevated to critical fire weather
  conditions in the plains through the week.

&&

.DISCUSSION /Through Sunday/...
Issued at 1153 PM MST Sun Feb 22 2026

It`ll be another active week across the forecast area, with winter
conditions and high winds expected in the mountains, and strong
winds with multiple days of potential elevated to critical fire
weather conditions across the lower elevations.

On Monday, we`ll kick off the week with mild and dry conditions
across the forecast area, underneath a broad upper-level ridge.
Temperatures are forecast to take a significant jump upwards from
Sunday`s, with afternoon highs climbing into the low to mid 60s
along the urban corridor and plains. This will put us roughly 8 to
20 degrees above normal across the entire forecast area. It`ll be
dry out there, with minimum relative humidity values dropping
between 10-15% across the majority of the plains in the afternoon,
though winds are expected to remain fairly light with a loose
pressure gradient in place, so while elevated fire weather
conditions are expected across the lower elevations, no critical
fire weather conditions are anticipated. Overnight, above-normal
temperatures will remain across the forecast area. Flow aloft will
begin to increase as a near 80kt, northwest to southeast positioned
500 mb jet sets up over Wyoming. This will influence how Tuesday
plays out, as it will put northern Colorado in the subsident right
exit region.

Tuesday- As discussed in the previous AFD, there are key ingredients
that can really "make or break" what happens with a mountain wave,
which can be the determination of how far down the foothills the
strongest winds make it. For Tuesday, there is high confidence that
winds are gonna be blowing across the mountains, but still some
uncertainties on how far east they will push. By early Tuesday
morning, the latest guidance shows things have stayed consistent
with winds at ridgetop near 80 kts and within 30 degrees of normal
(~290 degrees), lapse rates ranging between 3-6C/km, and the
aforementioned jet over Wyoming. Forecast soundings still show
nothing more than a hint of an inversion just above ridgetop, which
would be a good indicator that winds would lean more towards staying
anchored to the higher foothills, rather than being reflected all
the way down to their base. Additionally, moisture in the
mountains has been known to be a deterrent of mountain wave
amplification in the past, and with Pacific moisture expected to
increase (forecast soundings show a deep moisture profile west of
the Divide by 18-21Z) across the mountains through the day, this
could have an impact on winds on the lee side of the Front Range
(will they diminish sooner than currently forecast?). All of this
being said, strong winds are expected to increase across the Front
Range Mountains through the early morning Tuesday, reaching high
wind criteria along the Mummy Range down to the Indian Peaks by
roughly 8AM before spreading east into our typical windy spots
like Jamestown and Sugarloaf in the afternoon, with a fairly tight
gradient of lighter wind speeds across the lower foothills.
Latest hi-res guidance shows the strongest gusts reaching between
70-75kts (80-85mph) throughout the afternoon, before decreasing
and retreating back up the slopes through the evening. Considered
expanding the watch to include eastern Larimer County, but winds
are shy of high wind criteria over most of the eastern portion of
zone 38, however, expect the strongest winds to reach high wind
criteria in the typical windy spots from Wellington north to the
Wyoming border. The northern tier of the plains (generally
southern Morgan county northward) will see breezy conditions
coinciding with marginal relative humidity values (14-20%). This
would bring a few hours of near critical to critical fire weather
conditions where the RH is at its lowest. Will let the day shift
decide on fire weather highlights, but suspect portions of Weld
and Morgan Counties to reach criteria long enough to warrant a
highlight.

Winter conditions are expected to develop over the northern
mountains by Tuesday afternoon as Pacific moisture starts to make
its way into the high country ahead of the next shortwave progged to
move across the Rockies on Wednesday. With the aforementioned strong
winds, blowing snow will make for difficult travel conditions for a
few days.

Strong winds will continue Wednesday, becoming more widespread
across the lower elevations, but decreasing over the mountains.
Fortunately, relative humidities should generally remain above 20%
where gusty winds (35-55mph) are forecast over much of the plains,
keeping critical fire weather conditions at bay. As more of the hi-
res models come into play, we will need to continue to monitor for
the potential some channels of stronger winds reaching high wind
criteria, make their way across the northern plains Wednesday
afternoon behind a passing cold front. The latest RRFS shows gusts
between 55-60 mph coming off the Cheyenne Ridge as the front
passes, but these winds are not expected to persist for an
extended period of time, and this is just one model solution. As
the front slides south across the forecast area, there will be a
shot at light precipitation falling across the lower elevations,
though ensembles and operational models have yet to agree on this,
and anything that falls would not be significant (maybe a few
hundredths). PoPs were lowered across the plains to account for
the remaining uncertainty. At least we should get a decent little
dose of new snow to add onto our lacking snowpack, with the
current forecast bringing around 5-10 inches to the Front Range
Mountains, and slightly higher amounts to the Park Range. Snow
will continue across the mountains, with strong winds keeping
blowing snow and hazardous travel conditions in place into
Thursday morning.

Beyond the quick-hitting mountain snow, the rest of the long-term
period will shift focus back to fire weather conditions
developing across the lower elevations to end the week.






&&

.AVIATION /06Z TAFS through 06Z Tuesday/...
Issued at 1036 PM MST Sun Feb 22 2026

VFR conditions through the TAF period. Drainage winds overnight
should turn to a weak west-northwesterly direction during the
afternoon Monday, before returning to drainage again Monday
evening. No ceiling or visibility concerns at this time.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
High Wind Watch from Tuesday morning through Tuesday afternoon
for COZ033>035.

&&

$$

DISCUSSION...9
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion