279
FXUS65 KBOU 131134
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
434 AM MST Fri Nov 13 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 next week?

&&

.DISCUSSION /Through Thursday/...
Issued at 1201 AM MST Fri Nov 13 2026

Current satellite shows a clear night for much of the state with
only a few thin high clouds over western CO. To our east, a much
cooler airmass and its accompanying cold front have pushed over the
Great Lakes and across the central Great Plains, up against our
eastern counties. Given the clear skies in place, light easterly
winds, and a somewhat of a surge in dewpoints (low to mid 30s), at
least some patchy fog is likely over the eastern CO plains and along
the South Platte River valley in the early morning hours. Areas of
fog can already be seen slowly creeping over the CO-NE border. The
fog should clear by mid morning as temperatures rise.

High clouds will continue to increase over the region Friday as the
upper level ridge axis moves off to our east and a shortwave trough
drifts over the desert Southwest. The ascent and vorticity
enhancement with this disturbance will remain well to our south,
and no precipitation is expected. However, cloud cover should keep
temperatures a few degrees cooler, in the low to mid 60s at low
elevations and 40s-50s for the mountains.

Temperatures finally cool down to near-average values for the time
of year this weekend as a broad upper level trough (remnants of what
was once a potent mid-latitude cyclone) slides southeast over our
area. Areas of fog are likely to develop as far west as the I-25
corridor in the early morning hours Saturday as temperatures drop
into the mid 30s and southerly winds, as well as a lee surface
cyclone, advect higher dewpoints. The weakening upper level
trough will also bring a plume of Pacific moisture that should
promote light mountain snow and scattered rain showers over the
plains Saturday afternoon. In terms of snow, 1 to 3 inches of
total accumulation for this event seems reasonable at elevations
above 10kft, with locally higher amounts above 12kft. For the low
elevations, rain showers should remain quite light in intensity,
with only a trace up to a few hundredths expected mainly over the
east CO plains. A few snowflakes or a rain/snow mix cannot be
ruled out over the Palmer Divide late Saturday evening as the
system exits the region and temperatures begin to drop into the
mid 30s.

Sunday is shaping up to be a mostly sunny autumn day with
temperatures in the low to mid 50s for the Denver metro and east CO
plains, which is near-average for the time of year. An upper level
ridge will begin to build over our region on Sunday into Monday,
with temperatures expected to warm back up into the 60s once again
for much of the plains and foothills Monday-Tuesday. A pattern
change is expected to arrive by Wednesday as a shortwave trough
slides over northwest CO. This is also where uncertainty enters the
picture, with ensemble guidance showing increasing spread in
temperature and moisture through next weekend. At this time, our
northern mountains look to be favored for mountain snow with the
first wave on Wednesday. We are fairly confident in temperatures
dropping to seasonable values by the end of next week. Long-range
ensemble members and deterministic runs have continued to hint at
another system bringing more mountain snow chances, and potentially
some snow for the low elevations as well. However, it is far too
early to come to any conclusions about snow amounts or even
precipitation type. At this time, global model ensembles show a 15-
degree spread in temperature between the 25th and 75th percentiles
alone. Nevertheless, more active weather and cooler temperatures
seem to be in store starting mid next week, likely continuing
through Thanksgiving week.

&&

.AVIATION /12Z TAFS through 12Z Saturday/...
Issued at 434 AM MST Fri Nov 13 2026

VFR will prevail through about 06Z Saturday with slowly
increasing high clouds. After 06Z Saturday, low clouds and fog
are expected to form over parts of northeast Colorado. Whether DEN
gets fog depends on the placement of the Denver cyclone that
forms. Most models show DEN getting northwest winds which would
favor fog. The time frame for fog at DEN (and BJC) will be around
and after 12Z. As far as winds go, typical southerly drainage
winds will prevail into this morning (16-17Z) at DEN and APA.
Winds then become variable before turning northeast (19-21Z). A
Denver cyclone forms and is expected to be just southeast of
Denver, bringing the northerly winds. This could change if the
cyclone`s placement differs.

&&

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

&&

$$

DISCUSSION...AA
AVIATION...BM

NWS BOU Office Area Forecast Discussion