231
FXUS65 KBOU 111759
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1059 AM MST Tue Nov 11 2025

.KEY MESSAGES...

- Dry conditions and above normal temperatures are expected across
  the forecast area through Friday.

- A few hours of elevated to spotty critical fire weather
  conditions over the plains and I-25 Corridor today.

- An upper trough is expected to move across the forecast area
  Saturday and Sunday with a chance of precipitation for most
  areas.

&&

.DISCUSSION /Through Monday/...
Issued at 220 PM MST Mon Nov 10 2025

Water vapor satellite imagery shows high cloud cover increasing as
northwest flow aloft advects upper level moisture over the forecast
area. Relatively quiet conditions are expected through this
evening as an upper level ridge over the southwest United States
slowly shifts eastward.

Overnight tonight and into Tuesday morning, a shortwave will trek
across the Dakotas, turning flow aloft more westerly over
Colorado. Cross-barrier flow of 40-50 kts will bring wind gusts up
to 60 mph across the ridgeline of the Front Range mountains.
Resulting downslope flow will keep Tuesday morning lows in the 40s
along the foothills and adjacent plains, while farther eastern
plains and mountains/valleys will see morning temperatures in the
high 20s/30s. A weak cold front will cross the plains during the
day, bringing northerly wind gusts up to 25 mph. Elevated to
briefly critical fire weather conditions are possible, especially
in the southeastern plains, where relative humidity values will
dip below 15%.

Weak ridging will recover from the exiting shortwave on Wednesday.
Above normal temperatures are forecasted through Friday, with each
day expected to be in the high 60s/low 70s. There is a chance for
record breaking temperatures on Thursday (75 set in 1999).
Currently, ensemble solutions show a range of 70-73 dg as the
maximum temperature. However, if there is stronger cross-barrier
flow on Thursday, downslope winds could warm temperatures higher.

Ensemble guidance is in good agreement of an upper level trough
developing off the west coast and traveling east on Friday and into
the weekend. However, there are still disagreements in terms of
track and evolution. The deterministic GFS and ECMWF indicate the
trough splitting, with one piece of energy trekking across the
northern United States, and the other piece traveling across Arizona
and New Mexico. This would leave Colorado in between the two
disturbances, which would limit widespread precipitation chances
across our forecast area. There is higher confidence of light snow
showers for our mountains, with minimal accumulations expected. For
the plains, precipitation will depend on the track of the upper
level trough. Currently, NBM has 20-30% PoPs for the Palmer Divide
and plains, which seems reasonable at this time. In terms of
temperatures, a cold front will bring temperatures back to their
seasonal normals for the weekend, with highs in the 50s for the
plains and 30s/40s for the mountains/valleys.

&&

.AVIATION /18Z TAFS through 18Z Wednesday/...
Issued at 1059 AM MST Tue Nov 11 2025

Gusty W/SW winds from about 250 degrees have been stronger and
more persistent so far. However, with continued mixing, those
winds will trend more W/NW. Also, potential for anticyclone will
mean winds likely shifting more N/NE anywhere from 19Z-23Z. The
first push is already manifesting itself just to the northeast of
KDEN, with about a 30% chance this makes it`s way totally across
the airport 19Z-20Z, and a 50-60% chance it makes it over the
northeast portion of the airport. That initial surge could weaken
or mix out again through 21Z, but considerable uncertainty there.
Therefore, we`ll blend to a more NW component through this period
in the TAF, but the potential shift is certainly something to
watch in the near term. There is more confidence of a stronger
anticyclonic push late in the day, so we`ll forecast NE winds
developing 22Z-23Z. Then expect a transition to more SE by 01Z
before normal SSW winds develop by 03Z-05Z. Winds on Wednesday
will be lighter (<10 kts) and follow more normal diurnal wind
patterns. VFR conditons will persist with only SCT- BKN high
cirrus.

&&

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

&&

$$

DISCUSSION...MAI
AVIATION...20