905
FXUS65 KBOU 151142
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
542 AM MDT Thu Oct 15 2026

.KEY MESSAGES...

- Mountain snow continuing this morning across the northern
  mountains. Light additional snow accumulation`s possible, with
  travel impacts on some high mountain passes for the morning commute.

- First freeze of the season expected over most of the plains
  lateThursday night into early Friday morning.

- Drier and warmer again for the weekend and early next week.

&&

.DISCUSSION /Through Wednesday/...
Issued at 1111 PM MDT Wed Oct 14 2026

The upper level low continues to drift northeastward, with water
vapor satellite suggesting the center is somewhere near Berthoud
Pass as of 05z. This circulation is also evident on KFTG/KCYS,
with bands of rain and snow showers pivoting to the west/southwest
over Larimer and Jackson counties, while most of the snow showers
along the I-70 corridor had moved eastward over the last couple
of hours. Meanwhile, there`s been some patchy dense fog that`s
developed across the lower foothills and portions of the I-25
corridor. Models do not have a very good handle on where and how
long this will last, but it seems plausible that this would
continue for the next few hours before quickly diminishing
sometime in the early AM.

Almost all of the additional snowfall tonight will fall along and
north of the track of the 700/500mb lows overnight, meaning
little to no additional snowfall is expected along and south of
I-70. Even our far northern mountains may only see lower end
advisory totals through tomorrow morning, with most guidance
keeping the more significant QPF in Wyoming. We`ve tweaked the
timing of the Winter Weather Advisories to try to account for
this.

Rain and snow showers will likely be ongoing across the northern
CWA Thursday morning, with a band of precipitation pivoting from
northwest to southeast during the morning hours as the upper low
treks off to the northeast. Any additional precipitation across
the I-25 corridor is expected to be light (generally just a few
hundredths). Winds will pick up during the morning hours and
continue through the afternoon as 800-700mb flow increases to
30-40kt in a subsident/cold air advection regime. A few gusts of
40-45 mph will be possible along and east of I-25 during the late
morning and most of the afternoon.

North-northwest flow aloft will continue on Friday, but winds are
expected to diminish as the mid-level flow weakens and QG
subsidence also decreases. We`ll be left with a relatively cool
but sunny day with highs remaining in the mid 50s to perhaps low
60s across the plains.

A broad upper ridge will then be the focus for the weekend, with a
pronounced warmup likely for both Saturday and Sunday. Highs
across the plains are expected to rebound into the 70s, with dry
conditions. While winds will generally remain weak, there could be
some locally critical fire weather conditions over the far eastern
plains both Saturday and Sunday afternoon.

By next week, guidance generally begins to push the ridge off to
the east, leaving the region in weak southwesterly flow aloft. A
weak shortwave or two may attempt to push into the area by
early/mid week, leading to a gradual increase in rain and snow
showers across the higher elevations. However, the chances of any
meaningful precipitation looks rather low... with 90th percentile
QPF less than a tenth of an inch across the mountains through
Wednesday. Temperatures during this period will likely remain
above normal with highs in the 70s most days. There are hints of
a more organized storm system by this time next week, but there
(unsurprisingly) rather large differences in timing and location
of that potential system at this time.

&&

.AVIATION /12Z TAFS through 12Z Friday/...
Issued at 501 AM MDT Thu Oct 15 2026

Ceilings this morning are bouncing between LIFR, IFR, and MVFR.
Fog seems to have mostly cleared the area, with all TAF sites at
P6SM this morning. Ceilings will continue to bounce between flight
categories through the morning, with KDEN remaining ILS. Light
showers are moving into the TAF sites, with showers on and off
through roughly 17Z or 18Z today. Skies will clear behind the
showers bringing VFR and visuals back to the TAF sites by the
early afternoon. Winds will increase out of the north starting
around 14Z, with gusts of 24kts to 30kts. Winds will weaken
between 22Z and 00Z. Winds will become light and variable for the
evening. Models are hinting at the potential for some stronger
winds around 06Z from the northeast, but there`s quite a bit of
uncertainty on if those winds will actually mix down to the
surface or not.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 9 AM MDT this morning for COZ031-
033.

Freeze Watch from late tonight through Friday morning for
COZ038>051.

&&

$$

DISCUSSION...Hiris
AVIATION...AP

NWS BOU Office Area Forecast Discussion