162
FXUS65 KBOU 041105
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
405 AM MST Wed Nov 4 2026

.KEY MESSAGES...

- Precipitation will form across the mountains and foothills along
  and south of I-70 for this afternoon through early Thursday
  morning.

- Snowfall amounts of 3-10" with isolated higher amounts
  possible.

- The highest snowfall amounts and worst road conditions are
  expected for western Park County, possibly extending into
  northern Park County.

- Pleasant temperatures and dry conditions are expected Thursday
  through early next week.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1123 PM MST Tue Nov 3 2026

We are expecting a quiet overnight with mostly clear skies. Skies
will be partly cloudy in the morning with increasing clouds by
Wednesday afternoon for the high country, Denver metro, and the
adjacent plains. Temperatures will top out in the mid to upper 50s
for the plains once again. The trough and associated low are
currently over Nevada. As this feature moves east, it will bring us
the 2nd storm system of the week, which will quickly move through
our area on Wednesday afternoon and into Wednesday night. We expect
the highest impacts for the central and southern high country.

Precipitation will increase from west to east starting mid afternoon
on Wednesday in the high country. The precipitation shield should
shift south and east through Wednesday evening and into the
overnight. On Wednesday evening, scattered rain showers and perhaps
a few snowflakes mixing in are possible for the Palmer Divide. There
is a low but nonzero chance (~10-15%) that this potential could even
extend into far southern and western parts of the Denver metro. No
snow accumulation is expected in these locations. Some rain showers
are possible for southern Lincoln County late Wednesday night into
early Thursday morning as the low pushes off to the east of our area.

High resolution model guidance has shown an uptick in moisture
compared to model runs over the last 24-36 hours. As the afternoon
progresses on Wednesday, there should be some modest instability
present in the southern high country along with increasing lapse
rates. Snow levels are trending lower as well. Snow levels should
start around 9,000 feet early Wednesday afternoon. They are now
forecast to drop down to 7,500-8,000 feet on Wednesday evening. Snow
levels should drop even lower to 6,500-7,000 feet just as the system
starts to exit the area early Thursday AM. The track of the low
across our southwestern counties or just to the south would bring
northeast to east winds at the surface. This flow could extend up in
the atmosphere a few kilometers. In this type of flow, Park County
looks favored for some upslope flow/enhancement. In particular, the
southern Front Range foothills, the Mosquito Range, the Highway 285
corridor, and most of Park County look favored for the heaviest
snowfall totals from this system.

Altogether, most short-term models have trended up with snowfall
totals and QPF in the last 24-36 hours. QPF amounts of 0.25-0.75"
should be common in Park County and adjacent locations with isolated
higher amounts possible at the highest elevations. DESI
probabilities are honing in on the Mosquito Range/western Park
County where there is a 50-60% chance that these locations receive 6
inches or more of snowfall. Thus, we have issued a Winter Weather
Advisory for the mountains of Summit County, Park County, the
Mosquito Range, Indian Peaks, and South Park. It runs from 2pm
Wednesday to 2am Thursday. Most of Park County should get 3+ inches
snowfall with the Mosquito Range forecast to receive 5-10 inches of
snowfall with localized higher amounts possible. Areas along and
adjacent to the I-70 corridor above 7,500 feet, including the
northern Gore Range, are forecast to get 3-6 inches of snowfall with
areas to the north getting much less.

There is still good agreement that ridging aloft moves back in for
Thursday followed by a trough passing to our north on Friday. This
system will lack moisture for our area. As a result, there are only
low precipitation chances for Friday afternoon in the high country.
Temperatures are forecast to reach the mid to upper 50s for the
plains on Thursday and Friday. Ridging resumes once again for the
weekend and into next week. We expect dry conditions across our area
from Saturday through the end of the forecast period. The ridge is
expected to strengthen and the center should move closer to us for
the end of the weekend and into early next week. Mid 60s look
increasingly likely for Denver for Sunday and Monday according to
ensemble guidance. This would be 5-10 degrees above average for this
time of year. Temperatures on the eastern plains could even be
pushing 70 F. For Tuesday, more zonal flow could be in place
dropping high temperatures back into the low 60s for most of the
plains.

&&

.AVIATION /12Z TAFS through 12Z Thursday/...
Issued at 400 AM MST Wed Nov 4 2026

Winds were light drainage early this morning and will become light
and variable by 15z. By 18z winds will go light easterly and then
more ENE by 23z. By 04z this eveing winds will be NE and then may
shift to more NNW by 07z. By 10z winds will go to light drainage.

There will be an increase in mid clouds later this morning thru
the aftn but VFR conditions will remain in place.  There will be
a 10-20% percent chc of -shra at APA in the 23z-03z time period
with ceilings possibly dropping to 6000 ft. At BJC and DIA
ceilings are expected to stay at or above 10000 ft.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 2 PM this afternoon to 2 AM MST
Thursday for COZ034-037.

&&

$$

DISCUSSION...MV
AVIATION...RPK

NWS BOU Office Area Forecast Discussion