National Weather Service Forecast Discussion

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853
FXUS65 KBOU 262102
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
302 PM MDT Sat Sep 26 2026

.KEY MESSAGES...

- Drier and warmer this weekend, with highs reaching into the 80s
  across the plains.

- Decreasing chances (now 10%-30%) for mountain snow above
  12,000ft Monday through Wednesday.


- Potential for heavy rain Tuesday into Thursday, but confidence
  in amounts and locations remains low.

&&

.DISCUSSION /Through Saturday/...
Issued at 300 PM MDT Sat Sep 26 2026

It`s a quiet afternoon across Colorado with mostly sunny skies over
the plains and fair-weather cumulus over the mountains. Rain chances
for today remain low (12,000ft) that become cold enough
may see daily chances for some flurries up to a dusting. Some GFS
ensemble members do hint at some light mountain snow accumulations
with an upper level shortwave trough next weekend, while ECMWF
ensembles show zonal flow or even ridging and a return to warmer
temperatures. This will be another system to watch as the week
progresses.


&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1128 AM MDT Sat Sep 26 2026

VFR will persist with no shower/thunderstorms to contend with.
Airmass is drying and stabilizing, with only a high based sprinkle
confined to the mountains 20Z-02Z. Winds will become VRB through
20Z, and will then have a tendency to become light diurnal
upslope (E-SE) at speeds under 10 kts through 23Z. Those winds
will then return to normal S-SW 01Z-06Z and hold through about 16Z
Sunday. After that, winds will likely (>70% chance) turn more SE
and increase to speeds of 15G20-25 kts by 21Z-22Z. There will be
a chance of high based shower outflows with VRB winds late, but
main threat (PROB30) of that would hold off til just after 00Z
Monday.

&&

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

&&

$$

DISCUSSION...AA
AVIATION...20

NWS BOU Office Area Forecast Discussion