422
FXUS65 KBOU 080638
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1238 AM MDT Sat Aug 8 2026

.KEY MESSAGES...

- Elevated to locally critical fire weather conditions possible
  across the mountains and high valleys through the weekend.

- Hot this weekend with highs reaching 95 to 105 across northeast
  Colorado. A Heat Advisory is in effect for the northern I-25
  Corridor and Denver metro from 11 AM Saturday to 8 PM Sunday.

- Precipitation chances increase and temperatures decrease mid to
  late next week.

&&

.DISCUSSION /Through Friday/...
Issued at 1238 AM MDT Sat Aug 8 2026

An upper level high centered over the southwest part of the
country will continueto bring very warm to hot conditions to the
region this weekend and the first part of nextweek. For today,
the airmass warms 2-3C at 700mb, with greater warming across the
far eastern plains. This will put high temperatures in the 95 to
105 range across the urban corridor and eastern plains. Smoke
seemed to play a slight role yesterday, knocking a couple degrees
off our potential heating. The same will be possible today. The
00Z models show more smoke for today than yesterday, but not a
significant increase. Ingredients are there for Denver to reach
100 degrees today, but the wildcard will be the smoke and how much
it hinders warming. A slight speed max in the flow aloft will
travel across Wyoming today. Northern Colorado may see a slight
increase in winds this afternoon with gusts up to 25 mph. High-
based showers are expected to develop over the high country early
this afternoon and then progress eastward. Given how dry the
airmass is and the very high cloud bases, very little, if any,
rainfall will reach the ground. However, gusty outflow winds
reaching up to 50 mph are expected from the showers.Threat for
showers and gusty winds ends early this evening as the airmass
stabilizes.

Sunday`s weather is looking very similar to Saturday`s: hot,
smoky skies, and a chance for afternoon showers. One difference
will be an increase in moisture; precipitable water values will be
0.6 to 0.8 (in), a few tenths higher than Saturday. This will
increase the number of showers and thunderstorms and also lead to
a better chance for rainfall to reach the ground. The best
instability will be over the higher terrain, thus the best chance
for showers and thunderstorms will be there.

Moisture continues to increase for Monday and Tuesday with
precipitable water values reaching 0.7 to 1.0 (in). These
precipitable water values are 100-125 percent of normal. The
increase in moisture and clouds should cool things slightly, but
highs are still expected to be in the mid to upper 90s across
northeast Colorado. Scattered showers and thunderstorms are
expected to form over the high country on both days. They will
continue to struggle to survive off the higher terrain due to the
warm air aloft from the upper level high and limited instability.

The upper level high finally begins to weaken and shift southeast
of the Rockies on Wednesday. Flow aloft turns south-southwest,
helping to pull monsoon moisture into the region. Precipitable
water values increase to 120-160 percent of normal. This is
expected to lead to scattered to numerous showers and
thunderstorms. The loss of the upper level high and the increase
in moisture will cause temperatures to cool with highs in the
upper 80s to lower 90s across northeast Colorado. Moisture
continues to increase for Thursday and Friday. Precipitablewater
values climb to 140-180 percent of normal Thursday and Friday.
This will increase the chance of rainfall, and given the moist
airmass, a threat of heavy rainfall and localized flooding could
return. Temperatures cool off with highs only expected to reach
the mid 70s to lower 80s.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1238 AM MDT Sat Aug 8 2026

Smoke will persist through the next 24 hours and beyond, this may
affect approach slantwise visibilityat times. Otherwise, VFR
conditions will prevail. Southwest drainage winds will linger
through sunrise (12Z) and then start to turn clockwise becoming
northwest 16-17Z. High-based showers are expected to develop this
afternoon, after 19-20Z. Very little to no rainfall is expected,
but dry microbursts will accompany the showers with gusts up to 40
knots possible. The threat for showers and microbursts ends
01-02Z Sunday. After this, winds are expected to return to a
southerly drainage direction.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM this morning to 8 PM MDT Sunday for
COZ038>040.

&&

$$

DISCUSSION...12
AVIATION...12

NWS BOU Office Area Forecast Discussion