902
FXUS65 KBOU 010538
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1138 PM MDT Tue Jun 30 2026

.KEY MESSAGES...

- Critical fire weather conditions will be present in the high
  country today due to warm, dry and windy conditions.

- A couple strong storms possible across far northeastern Colorado
  late this afternoon/evening.

- Mainly dry Wednesday through Friday with elevated to critical
  fire conditions across much of the area.

&&

.DISCUSSION /Through Tuesday/...
Issued at 248 PM MDT Tue Jun 30 2026

It is sunny, dry, and breezy across much of Colorado this afternoon.
A shortwave currently sitting over Utah will continue to track
northeast into northern Colorado and Wyoming, and flow aloft is now
SSW. At the surface, strong southeasterly flow is advecting
dewpoints in the low 40s into north central Colorado as far west as
the I-25 corridor. Current satellite imagery shows cumulus cloud
coverage already increasing over the foothills. With DCAPE values in
the 1000-1500 J/kg range, virga showers are still on track to
develop this afternoon. Wind gusts up to 50-55 mph will be
possible with the outflows of the strongest dry microbursts. High-
res model guidance initially favors the northern I-25 corridor for
the development of high-based showers between 4pm and 6pm. The
far northeast plains of Colorado will have a better chance to see
a strong thunderstorm as high-based showers move into an
environment with higher precipitable water (PW ~1.00") and MLCAPE
in the early evening. Another shortwave will graze northern
Colorado tomorrow afternoon bringing a chance (20%-30%) for a few
high based showers over our northeast CWA, although the moisture
content of the airmass in place will be much lower than today`s
(PWs <0.50").

A longwave ridge over the eastern half of the U.S. will continue
to block the synoptic pattern through at least the end of this
week when flow is expected to become more zonal. Winds aloft
remain SSW/SW tomorrow and Thursday, becoming weaker as the week
progresses. While there is no strong signal for a pattern change
over the next couple days, a weak disturbance appears to arrive
late Friday into Saturday. Model guidance suggests a lee cyclone
developing over eastern Colorado Saturday afternoon, aiding the
transport of enough Gulf moisture for at least a few isolated
showers over the northeast Colorado plains. Uncertainty remains
regarding thunderstorm chances for the weekend at this time. Dry
conditions return by early next week with slightly above average
temperatures.

&&

.AVIATION /06Z TAFS through 06Z Thursday/...
Issued at 1128 PM MDT Tue Jun 30 2026

Light easterly winds will eventually turn northwesterly and then
to drainage overnight tonight. Any potential showers in the
vicinity will not impact operations. There is a very low (5%
chance) that fog or low clouds impact DEN in the morning. Any fog
and low clouds are expected to stay well east of DEN.

Wind speed and direction will be difficult to forecast during the
late morning and afternoon tomorrow. This is because a DCVZ will
likely setup over the southeast Denver metro. DEN usually ends up
having moderate easterly winds for much of the day in these
scenarios with winds turning more northeast in the late afternoon
and northwest in the evening. It appears the DCVZ will setup right
near APA. APA could see southeast or east winds tomorrow if the
boundary is to the north, however, they would see northwest winds
if the boundary is to the south. Otherwise, there is a small
chance (20%) that virga showers develop over the terminals late
tomorrow afternoon. It is possible variable gusty winds develop
from those virga showers. Additionally, smoke may impact
operations during the late afternoon and evening as fires across
the southwest US strengthen in the afternoon.

Winds will slowly turn to drainage Wednesday night.

&&

.FIRE WEATHER...
Issued at 248 PM MDT Tue Jun 30 2026

Critical fire weather conditions are possible over the high terrain
this afternoon with winds gusting up to 30 mph and humidities in the
teens. Elevated fire weather conditions are also occurring over
the Palmer Divide this afternoon with winds gusting as high as 40
mph, although humidities have remained in the 20%-30% range due to
the strong southeasterly flow in place.

Winds will become weaker tomorrow, just below the threshold for Red
Flag issuance. However, brief periods of gusty winds up to 30 mph as
well as humidities in the low teens will create elevated fire
weather conditions and spotty critical conditions in some areas. The
Palmer Divide will likely be closest to meeting critical fire
weather criteria due to the development of a Denver cyclone in the
vicinity, which could strengthen wind gusts (up to 35 mph) for at
least a brief period of time.

For Thursday and Friday, winds will be generally light (< 20 mph)
although humidities will drop into the single digits each afternoon,
particularly over the high terrain. Therefore, widespread elevated
fire weather conditions are expected through the foreseeable future,
with localized areas of critical fire conditions over the mountains
Friday afternoon.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Wednesday afternoon through Wednesday
evening for COZ212-214-216-241.

&&

$$

DISCUSSION...AA
AVIATION...Danielson
FIRE WEATHER...AA