188
FXUS65 KBOU 041136
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
536 AM MDT Mon Aug 4 2025

.KEY MESSAGES...

- 10-30% chance for high based thunderstorms across the northeast
  corner late this afternoon and evening.

- Very warm and dry this entire week; Monday through Friday.

- Increasing fire danger is expected in Jackson and Grand Counties
  this upcoming week.

&&

.UPDATE...
Issued at 425 AM MDT Mon Aug 4 2025

Latest model data indicates the 10-30% thunderstorm pops for the
northeast corner should last well into this evening; so I updated
that timing. Forecast soundings indicate what storms there will
be, should be high based and strong outflow wind producers with
DCAPE values above 1500 J/kg.

With the heating expected today and decreased available moisture
over the western half to western two-thirds of the CWA, fire
danger will be elevated this afternoon.

&&

.DISCUSSION /Through Sunday/...
Issued at 202 PM MDT Sun Aug 3 2025

A north to northeast low level flow has brought slightly cooler
temperatures and drier air to the area today. A few of the high-
res models show isolated showers/storms developing over the higher
terrain of Larimer County. These showers/storms then track
eastward through the late afternoon and evening hours. MLCAPE in
this area is less than 500 J/kg and precipitable water is
0.50-0.75 (in), which is 70-90% of normal. This limited moisture
and instability is expected result in high-based showers/storms
with gusty winds and little to no rainfall. There is slightly
better moisture and instability over the far northeast corner of
Colorado. Here storms may get stronger with brief heavy rain
possible.

A strong upper level high over the Central and Southern Rockies
will bring very warm to hot conditions to the region this week.
High temperatures across northeast Colorado are expected to reach
to the mid 90s to lower 100s each day this week through Friday.
This upper level high will also bring dry weather, with very
little rainfall expected. Beginning on Wednesday, moisture may
increase just enough for some high-based showers and
thunderstorms. If there is enough moisture for the high-based
showers to form. Gusty winds will be the main impact with little
to no rainfall expected from these showers and storms. Over far
northeast Colorado, southeast low level flow could bring enough
moisture for thunderstorms Monday and Tuesday late
afternoon/evenings, though chances appear low at this time.

An upper level trough pushes southeast into the northern states
late Friday and next weekend. The upper level high will weaken and
drift southward. Temperatures will cool for next weekend and
we`ll see a chance for showers and thunderstorms return to the
area.

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 533 AM MDT Mon Aug 4 2025

Models have southeasterlies at DIA this afternoon with normal
drainage wind patterns tonight. Wind speeds will get into the
13-20 knots range this afternoon and evening. There will be no
ceiling issues.

&&

.FIRE WEATHER...
Issued at 202 PM MDT Sun Aug 3 2025

Upper level high builds over the region this upcoming week with
very warm to hot temperatures Monday through Friday. Relative
humidities are expected to fall into the teens each afternoon,
with some single digit readings in the mountain valleys. Overnight
relative humidity recovery will be poor most nights above the
night time inversion. It will be breezy during the afternoons with
gusts to around 25 mph. This will create localized red flag
conditions some days. Very little to no precipitation is expected.
High-based showers/storms will be possible Wednesday over the
higher terrain, but any precipitation is expected to be light. The
chance for high-based showers/storms continues into Thursday and
Friday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE.........rjk
DISCUSSION.....Meier
AVIATION.......rjk
FIRE WEATHER...Meier