National Weather Service Forecast Discussion

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022
FXUS65 KBOU 140701
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1201 AM MST Sat Nov 14 2026

.KEY MESSAGES...

- Above normal temperatures and dry conditions will prevail
  today, followed by more seasonable temperatures this weekend
  into next week.

- Chances for rain and snow showers across the high country
  Saturday, with a few showers possible over the eastern plains.

- A more active storm track looking likely for next week.

&&

.DISCUSSION /Through Friday/...
Issued at 1158 PM MST Fri Nov 13 2026

No major changes have been made to the previous forecast. Fog is
still expected to spread west later tonight and into Saturday
morning as low level moisture gets wrapped around a surface low
north of Denver. The fog could be dense at times, lowering
visibilities to less than 1/4 mile over Denver, the I-25 corridor,
parts of Lincoln County, and the surrounding plains. The fog is less
likely to reach the higher terrain of the Palmer Divide and if it
does, it should be more patchy and shorter-lived.

A shortwave trough will bring a surge of mid level moisture to much
of the state on Saturday which will help promote mountain snow in
afternoon and evening. Flow at the 700mb level will be west to
northwest, favoring orographic lift for the central mountains and
the highest peaks of the Park Range. Model soundings sampled over
various mountain ranges in our area show relatively deep moist
profiles with saturation along the dendritic growth zone. However,
given the weak state of the shortwave as it slides over our area and
lackluster synoptic forcing for ascent, snowfall is expected to be
light orographic in nature. Accumulations in the 1 to 3 inch range
will be possible for elevations above 10kft, with locally higher
amounts above 12kt. Mountain valleys could also see some snow
showers throughout the afternoon, but no accumulation is expected
given the marginal surface and air temperatures (highs in the 40s).
For the Denver metro and east CO plains, fog may be slow to erode
and scattered low clouds could persist through early afternoon.
Despite the abundant moisture at the lowest levels of the
atmosphere, model soundings for Denver show a stubborn dry layer at
around the 700mb level. Any showers that try to develop over the
Denver area will initially struggle to reach the ground so we have
limited the better PoPs (17%-40%) to the late afternoon and
overnight hours. If showers are able to linger into the early
morning hours of Sunday (~30% chance), a few snowflakes to even a
light dusting of snow cannot be ruled out over the crest of the
Palmer Divide. Otherwise, patchy fog will be possible once again
Sunday morning over the parts of the Denver metro and CO plains.

Conditions dry out state-wide on Sunday afternoon as an upper level
ridge begins to build over the Four Corners. This ridge will warm
temperatures back up to well above average for the season Monday
through Tuesday, with afternoon highs in the low 60s for the plains,
and 50s at the mountain valleys. Tuesday afternoon could be breezy
as the pressure gradient tightens ahead of the next system and
higher wind speeds aloft from the jet positioned over the area mix
down to the surface.

A shortwave trough is still on track to bring mountain snow on
Wednesday with the Denver metro and east CO plains remaining dry.
While there is still quite a bit of uncertainty with this system, at
least a couple of inches of snow accumulation seem reasonable for
the central and northern mountains. Beyond Wednesday, model
ensembles and deterministic runs show fundamental differences with
every run cycle. Perhaps the only "change" has been a slight trend
towards cooler solutions that bring a cutoff low to the Four Corners
region sometime late next week. At this time, ~40% of the NBM
members show at least one inch of snow for Denver within a 72 hour
period. There is also little to no agreement in the timing of this
system, with some solutions bringing the cutoff low into the area as
early as Friday morning, while others push this system back to
Tuesday of Thanksgiving week. What we do know at this time is that
temperatures in long-range ensembles keep trending at or below
average for the long term (days 8-15), increasing our confidence
in a colder end to November.


&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1100 PM MST Fri Nov 13 2026

A Denver cyclone will strengthen overnight, bringing a wind shift
to the northwest at DEN and BJC between 09Z and 11Z. Moisture
increases with the wind shift and fog is expected to develop an
hour or two after the wind shift. APA is expected to maintain a
more westerly flow, limiting the fog threat, but it will be close
if fog moves in. The fog is expected to persist through at least
15Z and could linger as long as 17-18Z. Increasing mid and high
clouds will likely slow warming and the dissipation of the fog.
Low clouds persist through Saturday across the plains, and there`s
a 30 percent chance they linger through the day at BJC and DEN if
winds stay a northeast direction. There`s also about a 30 percent
chance for rain showers 20Z to 03Z with ceilings dropping to 4000
to 6000 feet. For late Saturday night and Sunday, more low clouds
and fog are likely (60-70% chance) at DEN and BJC.

&&

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

&&

$$

DISCUSSION...AA
AVIATION...BM

NWS BOU Office Area Forecast Discussion