National Weather Service Forecast Discussion

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032
FXUS65 KBOU 231938
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
138 PM MDT Fri Oct 23 2026

.KEY MESSAGES...

- Breezy across portions of the plains through the late afternoon.

- Cooler weather returns this weekend with chances for rain,
  mainly for the eastern plains. An overall drying trend emerging
  for most of the Denver metro and I-25 corridor.

- A cool start to next week, but a warming and drying trend likely
  by mid-week.

&&

.DISCUSSION /Through Friday/...
Issued at 134 PM MDT Fri Oct 23 2026

It`s been quite breezy this morning across portions of the plains
and increased flow aloft and weak subsidence has allowed gusts up to
25-40 mph. Guidance is in good agreement that these breezy winds
will stick around this afternoon, before a noticeable drop-off
occurs around sunset. We should stay mostly dry today as current
water vapor satellite imagery shows drier air being advected into
the region with the upper level low tracking across Idaho and
Montana. However, we still could see a few showers (15-20% chance)
and possibly a thunderstorm later this evening across Lincoln
county. Some hi-res guidance seems a bit bullish with the
potential, but with SPC mesoanalysis showing weak instability
later today, can`t rule out gusty outflows with any thunderstorm
that does develop.

A pattern change is still looking likely on Saturday as a strong
cold front is slated to arrive early in the morning. This front
will bring gusty northerly winds (potentially up to 30-40 mph at
times across the northern plains) and much anticipated cooler
temperatures. For highs on Saturday, we should only reach up to
the mid-50s across the plains. Aloft, the upper level shortwave in
southern California will become a closed low, with southwest flow
advecting moisture into the region once again. This will bring
another round of rain showers (and high mountain snow) from the
south to the north by the afternoon and evening. As of right now,
CAMs favor the bulk of the precipitation with the eastern plains,
as the Denver metro and areas north will be battling the dry
northern air. However, short-range forecast soundings do show some
moistening of the lower levels which could allow a few showers
bringing light rainfall there by the evening.

Guidance has come to slightly better agreement for Sunday as the
upper level low weakens and treks across Colorado throughout the
day. Recent GEFS run has noticeably trended warmer for
temperatures (aligning more with the ECMWF) as the drier solutions
look more favorable for the morning and early afternoon. For this
reason, did lean on the NBM and nudge max temperatures up a
couple of degrees, and won`t be surprised if some portions of the
plains reach the low 60s. Despite the warmer/drier solutions
looking favorable, we still could see rain/snow showers (30-40%
chance) in the mountains Sunday morning. As the upper level system
begins exiting Colorado late Sunday into early Monday morning,
that is when the plains have better chance for an additional round
of rain showers.

We will start to dry out by late Monday morning as weak
subsidence takes over, with relatively weak flow aloft. By
Tuesday/Wednesday, flow aloft will increase and turn more
westerly/southwesterly ahead of another upper level shortwave.
Some uncertainty remains with the track of the system, but the
shortwave may be too far north of Colorado for us to see decent
precipitation. With cross-barrier flow increasing, we could be
looking at breezy-to-strong winds for our high county. Too early
to be sure, but worth watching out for. In terms of temperatures,
ensemble guidance does favor slightly above seasonal normals (mid
60s) through the end of the week.

&&

.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 1144 AM MDT Fri Oct 23 2026

Gusty south/southwesterly winds are present at all three TAF sites
early this afternoon. Winds are expected to increase a bit
further for the mid afternoon, with gusts around 30 to 35kts.
Winds will start to weaken around 00Z, but we could still see a
few lighter gusts (around 20kts) stick around DEN until 02Z.
Models are struggling a bit with the winds late this evening and
early overnight. We could see light drainage winds, but we could
also see light and variable winds ahead of the approaching system.
A cold front will move through the TAF sites around 15Z, bringing
stronger northeast winds and lower ceilings. CIGs are forecast to
drop to 6000ft or below at DEN by 17Z tomorrow. Right now, we do
expect APA and BJC to remain VFR through the morning, but ceilings
will lower as we go through the morning and into tomorrow
afternoon.

&&

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

&&

$$

DISCUSSION...MAI
AVIATION...AP

NWS BOU Office Area Forecast Discussion