467
FXUS65 KBOU 301911
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
111 PM MDT Fri Oct 30 2026

.KEY MESSAGES...

- Areas of again fog tonight across northeast and eastern Colorado.

- Mild and mostly dry through Saturday.

- Unsettled weather returns late Sunday and Monday.Mountain snow
  is likely (>70% chance) above 8500ft during thistime. High
  uncertainty remains for the foothills and plains.

&&

.DISCUSSION /Through Friday/...
Issued at 111 PM MDT Fri Oct 30 2026

Water vapor satellite imagery showsa shortwave trough over
southern California bringing widespread clouds and scattered rain
showers to the Desert Southwest. Ahead of this, there is a dry
slot which will result in mostly clear skies for northeast
Colorado through this evening. High clouds then increase late
tonight and persist through Saturday morning. At the surface, the
pattern changes very little as a surface trough remains near the
base of the foothills, which will help keep low level moisture in
place over northeast Colorado. This will lead to another round of
fog late tonight and Saturday morning. The mid and high clouds
associated with the shortwave trough tracking east-northeast
across the intermountain west will shift east of the area midday
Saturday. Mostly sunny skies are expected during the afternoon,
helping to push temperatures into the upper 50s to mid 60s across
northeast Colorado.

Southwest flow aloft will increase during the day Sunday as two
systems off to the west take aim at the region. The first one
system, a shortwave trough moves across southern California and
tracks east-northeast Sunday and Monday. This system will run
ahead of the second system on Sunday, carrying subtropical
moisture with it and, like many of the recent systems, bring
moderate to heavy rain to the Desert Southwest and Four Corners
Region. For north central and northeast Colorado, this has
resulted in scattered showers over the mountains and just cloudy
skies for northeast Colorado. The second system tracks eastward
across Oregon and northern California Sunday and then moves across
Colorado Monday. The best chance for rain and mountain snow will
come late Sunday night and Monday as the main trough moves
overhead. The snow level starts off high, above 11,000 feet but
quickly lowers to 8,500 to 9,000 feet by Monday morning. Snow is
expected to continue into Monday night when flow aloft turns
north-northwesterly, a somewhat favorable direction for orographic
lift across the north central mountains. Temperatures will be
cool Monday due to the overhead trough and cloud cover. Northerly
flow behind the trough Tuesday will keep temperatures cool with
highs in the 50s with dry conditions.A few earlier model runs
combined these two systems over the Central Rockies producing a
strong storm system, but this scenario now looks very unlikely.

The broad troughiness shifts east of the area sometime late
Tuesday/early Wednesday with ridging replacingit, most likely for
Wednesday. We expect to see a bump up in temperatures with dry
conditions. The ridging is expected to progress east of the area
on Thursday. What replaces it is still unclear. The next upper
level trough moves over the western states onThursday. Still very
little model agreement on the placement, strength, and track of
the upper level trough for Thursday and Friday. For the forecast,
temperatures should be near normal. We will have some low PoPs in
the mountains and keep the plains dry for now.

&&

.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 1126 AM MDT Fri Oct 30 2026

Fog has moved out of the TAF sites, leaving VFR conditions through
this evening. Winds will be light from the east/northeast this
afternoon, becoming light and variable this evening, and turning
towards drainage overnight. Models have another circulation
forming to the north and east of DEN, turning winds northerly or
variable at the TAF sites around 12Z. Fog is forecast to develop
again in the early morning, approaching BJC and DEN around 10Z or
11Z, potentially moving over the airports between 12Z and 16Z. We
have a tempo for LIFR conditions during that time window at DEN
and BJC. Fog will start to clear between 16Z and 18Z. Once again,
fog is expected to stay just to the north of APA.

&&

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

&&

$$

DISCUSSION...BM
AVIATION...AP

NWS BOU Office Area Forecast Discussion