AFOS product AFDBOU
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Product Timestamp: 2026-11-14 12:09 UTC

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FXUS65 KBOU 141209
AFDBOU

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

.KEY MESSAGES...
 
- Cloudy and cooler today with areas fog this morning across
  northeast Colorado.

- Scattered rain and mountain snow showers, mainly south of I-70.

- A return to mild and dry conditions Sunday through Tuesday.

&&

.UPDATE...
Issued at 509 AM MST Sat Nov 14 2026

The recent high-resolution model runs have trended closer to
global models, showing the best lift and moisture staying south of
I-70 through this evening. Lowered PoPs and precipitation amounts
north of I-70 due to this. Most models are dry, but a few show
light precipitation (less than a tenth inch). Fog is spreading
across northeast Colorado as expected. Webcams and observations so
far show only a couple spots where visibility is a quarter mile or
less. Will hold off for now on issuing a Dense Fog Advisory, but
will continue to monitor.

&&

.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 /12Z TAFS through 12Z Sunday/...
Issued at 509 AM MST Sat Nov 14 2026

Fog has moved into DEN and BJC and will be close to getting into
APA. Chances are high that a tempo was added for the fog. Mid and
high clouds will limit warming, slowing the fog's dissipation. For
DEN, the low clouds/fog likely won't dissipate until 18Z to 19Z. 
As far as winds go, west-northwest winds are expected to weaken
and shift to north to northeast after 18Z. The chances for showers
have decreased as the best lift and precipitation are expected to
stay south of I-70, so removed the PROB30 for the showers. The fog
is expected to return late tonight after 09Z Sunday and linger
into Sunday morning.  

&&

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

&&

$$

UPDATE...BM
DISCUSSION...AA
AVIATION...BM