National Weather Service Forecast Discussion

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827
FXUS65 KBOU 212355
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
555 PM MDT Tue Oct 21 2025

.KEY MESSAGES...

- Potential for some showers Thursday into Friday, with best
  chances in the mountains and across the Palmer Divide.

- Potential for an impactful system Sunday and Monday of next
  week. Most likely impacts will be strong winds and mountain
  snowfall.

&&

.DISCUSSION /Through Tuesday/...
Issued at 318 PM MDT Tue Oct 21 2025

Skies will remain clear into Wednesday except for a few transient
wave clouds. As the upper ridge and surface high drift eastward,
winds on Wednesday may be even lighter than today`s, with little
change in temperature. With clear skies, dry air, and light winds,
cold spots should radiate well, so we lowered mountain valley
temperatures. Most of the plains should be above freezing though,
and those colder spots have had hard freezes already.

Thursday will turn a little more active across the state, as a
weak shortwave drifts into southwest Colorado during the day, then
meanders across the southern half of the state Thursday night into
Friday. This system looks fairly warm (snow levels generally AOA
9kft) and moisture starved, but is slow moving enough to at least
produce some modest QPF/Snow across mainly the I-70 mountains
through Friday. Forecast snow amounts are generally in the 1-4"
range for the higher peaks, most of which falls Thursday afternoon
into Thursday night. There could be a few showers that drift into
the lower elevations, but any meaningful rainfall looks unlikely.

Brief, weak ridging will attempt to develop on Saturday as the
previous trough closes off into a weak upper low and stalls over
the southern Great Plains. Mild temperatures are expected with
highs near 70F for the Denver metro.

We should see a transition towards a more active pattern for the
end of the weekend into early next week, with one or more
shortwaves rippling through increasingly strong west/northwest
flow aloft. There`s a good signal across ensemble guidance for a
brief shot of mountain snow late Sunday through most of Monday.
There are a handful of ensemble members (

NWS BOU Office Area Forecast Discussion