National Weather Service Forecast Discussion

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952
FXUS65 KBOU 270513
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1113 PM MDT Fri Jun 26 2026

.KEY MESSAGES...

- Widespread and prolonged critical fire weather conditions will
  be present in the high country this weekend as warm, dry and
  windy conditions develop, continuing at times into early next
  week.

- All areas will trend warmer and drier this weekend, with little
  change into next week.

&&

.DISCUSSION /Through Friday/...
Issued at 146 PM MDT Fri Jun 26 2026

Early afternoon convection has been a bit more feisty than
originally anticipated. The latest SPC Mesoanalysis shows just
enough of a favorable combination of CAPE (>1000 SBCAPE) and shear
(effective layer shear ~30kt) that`s led to a few stronger
updrafts on the west metro, southern Foothills, and Palmer Divide.
The environment is marginally more favorable along and east of
I-25, so it appears reasonable to expect a gradual increase in
the severe threat over the next few hours as storms push off to
the east. ACARS data and KFTG VAD show largely straight line
hodographs, suggesting that multicell convection and splitting
supercells will be the predominant storm modes through the
afternoon and evening hours as activity shifts into the eastern
plains.

A prolonged period of elevated to critical fire weather conditions
is expected this weekend into next week. As a large trough stalls
across the northwestern CONUS, strengthening dry, mid-level flow
will lead to warm and windy conditions, especially across the
higher elevations. Temperatures across the plains are likely to
reach the 90s both Saturday and Sunday, with mid-90s possible
across the Denver metro.

The overall pattern is not expected to change significantly next
week, with a persistent trough across the northwestern CONUS and
a large ridge firmly anchored near the Ohio Valley. That will
leave Colorado in a mostly dry pattern with south/southwesterly
flow aloft. A shortwave or two rippling through the trough to our
northwest, we may see a weak cold front or two attempt to work
into the region. However, the model consensus strongly favors
above normal temperatures and dry conditions continuing through
the next several days.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1109 PM MDT Fri Jun 26 2026

A boundary was over the wrn suburbs of Denver and was moving
eastward. This boundary is fighting rather gusty SSE winds ahead
of it, so it may not make it to DIA or APA in the next hour. BJC
currently has gusty west winds up to 40 mph. Winds will become
drainage by 07z. On Sat, gusty SW/WSW winds will develop by 14z
and continue thru the aftn. Gusts from 30 to 35 mph will occur
from late morning into early Sat evening. Meanwhile, VFR
conditions will be in place thru the period.

&&

.FIRE WEATHER...
Issued at 146 PM MDT Fri Jun 26 2026

Critical fire weather conditions remain likely across all of the
high country on Saturday. A much warmer and drier airmass moves
into the region during the day, with winds also strengthening
considerably across the higher elevations. Relative humidity is
expected to fall to around 10-15% during the afternoon with wind
gusts of 35-50 mph possible.

The warm, dry, and windy conditions will continue on Sunday across
much of the same area. There may be some very modest improvement
to minimum humidity values across the northern mountains, but
critical fire weather conditions are still likely to continue. The
pattern is not expected to change significantly next week, with
elevated to critical fire weather conditions possible each day.

There were two changes of note with this afternoon`s forecast
package. First, a Fire Weather Watch was issued for Sunday across
much of the high country. Second, the southern Foothills fire
weather zone was added into Saturday`s Red Flag Warning and
Sunday`s watch after some additional coordination with fuels
experts. While the northern half of the zone has seen significant
rainfall over the past few days, the southern half of the zone
remains very susceptible.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM Saturday to midnight MDT Saturday
night for COZ211>214-216>218.

Fire Weather Watch from Sunday morning through Sunday evening
for COZ211>214-216-218.

&&

$$

DISCUSSION...Hiris
AVIATION...RPK
FIRE WEATHER...Hiris

NWS BOU Office Area Forecast Discussion