610
FXUS65 KBOU 211810
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1210 PM MDT Wed Oct 21 2026

.KEY MESSAGES...

- Warm and dry conditions continue across the lower elevations for
  the next few days, with scattered light rain and snow showers
  across the higher elevations.

- Cooler, unsettled weather potentially returns this weekend
  across the forecast area, including the Front Range/I-25
  corridor.

- At least a brief warm-up likely sometime early or mid-week next
  week.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1142 PM MDT Tue Oct 20 2026

The next couple of days will be dominated by broad south-
southwesterly flow aloft, as a strong trough to the west slowly
drifts off to the northeast, while a ridge slowly builds just to
the east of our forecast area. Embedded in the flow is some
extremely impressive moisture. Forecast PW and 500/700mb specific
humidity increases significantly over the next 24 hours or so,
with most of these values reaching standardized anomalies of 4-6
sigma... well outside climatology for this time of year. Of
course, the flow aloft is rather unfavorable for significant
orographic precipitation here. We should still manage scattered
rain and snow showers both Wednesday and Thursday, but the more
impressive rainfall totals will be confined to southwest Colorado.
The pattern will also favor above normal temperatures across the
region, with snow levels sitting around 12-14kft, and highs in the
70s across most of the plains.

The mid-level flow strengthens a bit on Friday as a shortwave
rotates around the parent trough axis from southeastern Utah into
western Wyoming. 700-500mb flow approaches 30-40kt Friday
afternoon with a generally dry/subsident airmass... which should
allow for a few gusts of 30-40 mph across the eastern plains. A
fairly strong lee cyclone over northern Colorado would likely
limit wind gusts along and north of I-76, meaning that the
northwest Denver metro could see a fairly calm day while the
southeast metro ends up rather breezy. These details are hard to
pinpoint but should become more clear over the next couple days
where CAMs will be available. Across the mountains, there could be
a few showers during the day but most of the moisture exits the
area pretty quickly.

While the main trough ejects out of the region on Friday,
guidance is insistent that at least one piece of this trough will
be left over the desert southwest. There`s still considerable
spread across both the physics and AI-based forecast guidance in
this period, though it appears we are starting to see a gradual
convergence towards a single solution, where the leftover piece of
the trough drifts northward and closes off sometime on Saturday.
That closed low then lifts northeastward and eventually interacts
with a relatively confluent northern jetstream... leading to the
upper low shearing out Sunday into Monday. The 700mb low, though
weaker throughout the period, follows a similar track, with the
flow briefly aligned to advect some deeper moisture into eastern
Colorado Saturday night through Sunday.
Current winds are light and variable over the Denver area with a
shift to the ESE expected in the next hour or two. Southeasterly
winds should pick up (~12KT) at around 21Z at KDEN and KAPA, with
much weaker speeds at KBJC. Southerly winds will begin to develop
over much of the CO plains and Denver metro in the evening, with a
light (

NWS BOU Office Area Forecast Discussion