National Weather Service Forecast Discussion

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166
FXUS65 KBOU 232348
AFDBOU

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

.KEY MESSAGES...

- Breezy across portions of the plains into the early evening.

- 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 /00Z TAFS through 00Z Sunday/...
Issued at 532 PM MDT Fri Oct 23 2026

At DEN and APA, winds are still gusty from the south/southwest as
of early this evening. Winds will start to weaken around sunset,
however we are expecting a few gusts around 25kts to continue on
and off through roughly 03Z. Winds will remain around 11kts from
the southwest through midnight, becoming light and variable for a
good portion of the overnight period. Winds will turn more
northerly early tomorrow morning, with gusty winds accompanying a
cold front for a few hours in the late morning. In the afternoon,
winds will be lighter from the northeast with the potential for
showers starting around 21Z or 22Z.

At BJC, there`s a small circulation near the airport which has
flipped winds more southwesterly and decreased speeds. Winds will
gradually turn more westerly, remaining there until winds become
variable around midnight. Winds will pick up from the north
around 13Z, with rain chances increasing near 22Z.

VFR conditions are expected through the rest of today and tonight,
with CIGs lowering behind the front in the morning and afternoon
tomorrow. Right now, we have ceilings staying around 3000ft to
5000ft through the end of the TAF package, but there is some
potential for CIGs to drop below MVFR thresholds near the end of
this package.

&&

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

&&

$$

DISCUSSION...MAI
AVIATION...AP

NWS BOU Office Area Forecast Discussion