289
FXUS65 KBOU 252011
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
211 PM MDT Wed Mar 25 2026

.KEY MESSAGES...

- Another unseasonably warm day Thursday with locally critical
  fire weather conditions, but cooling and gusty northeast winds
  behind an afternoon cold front Thursday afternoon.

- Some light precipitation Thursday night into Friday morning.
  Much cooler.

- Temperatures warm well above normal again for the weekend into
  early next week.

- Signs of a pattern change by the mid to latter portions of next
  week, but highest chances of meaningful precipitation confined
  to the mountains.

&&

.DISCUSSION /Through Wednesday/...
Issued at 211 PM MDT Wed Mar 25 2026

Summer warmth in full force across the forecast area this
afternoon, with record highs falling left and right and
approaching all time March record highs once again. For tonight,
we`ll see another unseasonably warm night with some locations at
the base of the foothills potentially staying in the 60s once
again. That just shows how anomalously warm this airmass is, when
nighttime lows still exceed our normal max temperatures (today`s
normal is 59F in Denver). Most other plains locations will see mid
40s through the 50s however, with a little more pronounced
inversion.

Even those inversions will be quite shallow though and thus
expect another quick warmup Thursday ahead of a cold front. We`re
still uncertain about the timing of the front, although it appears
we could see a weak pre-frontal shift to the north or northeast
in the morning across the plains, followed by the real cold front
during the afternoon. Given the shallow inversions to start the
day, we`ve bumped up the high temperatures from previous forecasts
which now pushes us to record or near record highs across the
mountains and along the I-25 Corridor. Denver will be pushing up
against the daily record (and old monthly March record of 84F)
set in 1971, so the chances there are rather low (45 mph possible
with the front. Winds settle down overnight, but with mid level
instability, upslope, and enough moisture advection we`ll actually
have a chance of light showers especially in/near the Front Range
and I-25 Corridor. These don`t look significant, but at least a
small 20-40% chance of a tenth of an inch liquid equivalent
in/near the foothills. Temperatures would turn cold enough for a
dusting of snow potential in the foothills and even a few flakes
possible on the adjacent plains by late Thursday night and Friday
morning.

Friday will be a much cooler day, with high temperatures likely
staying a few degrees below normal for a change.

That cooling will be very short lived as lee troughing develops
by the weekend and warm westerly flow dominates our weather under
a flat ridge. Highs are expected to rise back into the lower 80s
across the I-25 Corridor and plains by Sunday. Mountain areas will
also warm again, continuing the melt of our already depleted
snowpack.

For those looking for a pattern change, the various ensembles
continue to point toward more troughiness, cooler temperatures,
and a better chance of more meaningful precipitation for the
middle and end of next week. It starts benignly with just a hint
of subtropical moisture and a few light showers starting by
Monday and Tuesday, mainly in the mountains. There is agreement
that more beneficial precipitation arrives for the mountains by
Wednesday and Thursday, as ensembles for a change show above
normal precipitation anomalies during the latter half of next
week. For the plains, it`s more uncertain as we`ll be on the edge
of the storm track. We are more likely to be sheltered by the
mountains (~70% chance) due to southwest flow aloft, but if the
storm track is slightly farther south we may be able to tag some
upslope with beneficial precipitation (30% chance). Fingers
crossed for those that want a change back to spring.

&&

.AVIATION /18Z TAFS through 18Z Thursday/...
Issued at 1140 AM MDT Wed Mar 25 2026

VFR conditions through the TAF period. Winds are currently gusting
from the northwest at all terminals, with APA and BJC gusting the
strongest (up to 23 kts at times). Winds at DEN should continue
to stay below 20 kts. However, a rogue gust up to 22 kts is
possible for the next two hours. After 22Z-23Z, light and VRB
winds are expected at DEN and APA, as they gradual turn clockwise
to drainage by 05Z (BJC should continue to gust from the
northwest through 01Z).

For tomorrow, drainage winds will hold on till till mid-morning.
Guidance has indicated a light pre-cold front surge for DEN and
BJC (APA should see NW winds instead), with winds coming from
350-020 degrees (generally under 10 kts). Some uncertainty with
timing of cold front (could be between 21Z and 02Z). For now, have
decided to go with 21Z. But this may be delayed by a couple of
hours. With the arrival of the front, winds could initially gust
up to 35 kts. With this magnitude of winds, blowing dust is a
possibility so have introduced a TEMPO for BLDU with 6SM
visibility between 21Z and 23Z. However, the timing of the TEMPO
group will depend on the timing of the cold front. Mid-level
moisture will be advected into the region behind the front,
resulting in lowering of ceilings by the early afternoon (should
stay above 6000 ft).

&&

.FIRE WEATHER...
Issued at 211 PM MDT Wed Mar 25 2026

Elevated to locally critical (northern border) fire weather
conditions will ease by early this evening as winds subside. Only
poor (in/near lower foothills) to moderate humidity recover will
occur overnight.

Thursday will feature warm and initially dry conditions, with more
record warmth in/near the mountains and adjacent plains before a
cold front arrives. The strongest pre-frontal winds will be felt
in the highest foothills and Park County. We`ve issued a Red Flag
Warning for South Park due to gusty winds to around 30 mph and
humidity falling below 15%. Most other locations in the mountains
should see RH staying just above critical thresholds. Another area
of critical Red Flag conditions are expected to develop over
southern Lincoln County. That will be due to a combination of
prefrontal heat and breezy conditions, and then a sharp shift of
strong, gusty winds associated with a cold front that will sweep
across all of the plains during the afternoon. Conditions will
improve behind the front with cooling temperatures and higher
humidity, but only a gradual reduction in winds is expected
through Thursday evening.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM to 6 PM MDT Thursday for COZ214-247.

&&

$$

DISCUSSION...20
AVIATION...MAI
FIRE WEATHER...20

NWS BOU Office Area Forecast Discussion