National Weather Service Forecast Discussion

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780
FXUS65 KBOU 091212
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
512 AM MST Fri Jan 9 2026

.KEY MESSAGES...

- Scattered snow showers continue this morning. Higher amounts are
  still expected to fall across the southern foothills and Palmer
  Divide through the early morning.

- Winter Weather Advisories remain in place through 11 AM today,
  with slick conditions expected for the morning commute. Gusty
  winds leading to patchy blowing snow may reduce visibilities
  along I-70 east of Denver.

- The coldest temperatures will occur Friday night with lows in
  the low teens across the plains and urban corridor.

- Moderating temperatures this weekend, with dry weather
  prevailing through early next week.

- The next chance for precipitation will come Wednesday into
  Thursday.

&&

.UPDATE...
Issued at 505 AM MST Fri Jan 9 2026

Early morning radar and satellite show the upper and mid-level
trough of low pressure spinning away in eastern Colorado. Downslope
winds, off the Cheyenne Ridge, have started to clear out the
precipitation/snow from north to south across northern Colorado.
There is still enough of an upslope component in the southern
foothills and Palmer Divide to allow for a localized increase in
snow rates, but we still are sitting at under 0.5"/hour
accumulations.

Winter Weather Advisories continue through 11AM MST this morning,
thereafter patchy blowing snow is likely, mainly over the I-70
plains corridor, with stronger northerly winds sweeping over the
plains. By the mid-afternoon hours we should start to see a lot more
sunshine and winds slackening. This will lead to a fairly cold,
slightly below seasonal averages, for overnight lows into Saturday
morning. Even with the snow cover in place, we should warm close
to average for daytime highs on Saturday and likely start to melt
off a majority of the snowfall we just picked up.

&&

.DISCUSSION /Through Thursday/...
Issued at 248 PM MST Thu Jan 8 2026

Water vapor imagery shows a departing shortwave trough currently
over southern Iowa with the deformation zone on the west side of
the trough departing eastern Colorado. The QG ascent that was
over our forecast area has shifted to neutral stability this
afternoon resulting in limited coverage of snow showers. However,
the steep lapse rates in the mountains have lead to a few
scattered snow showers developing over the higher terrain. Some
of these may drift over the western I-25 corridor before
dissipating with minimal snow. Without QG forcing aloft, these
scattered weak snow showers will be the only precipitation that
occurs through the evening hours.

Water vapor imagery also shows a shortwave trough that is becoming
stronger over Arizona. This trough will head eastward tonight and
will end up over the Oklahoma panhandle Friday evening. This
trough will bring weak QG ascent to our forecast area especially
the southern half of our forecast area later tonight. Around
midnight to 3AM tonight, models have been consistent in showing a
cold front with moderate northerly winds moving through the I-25
corridor. Given the moisture currently in place, this front will
help to develop snow showers over the I-25 corridor and southern
foothills tonight. While high resolution models are all over the
place regarding snow in the Denver metro tonight, the thinking is
that 0.5-2" of additional accumulation is still likely to fall
with the higher amounts on the south side of the metro. Over the
Palmer Divide and eastward into Lincoln County, the upslope flow
behind the front along with the QG ascent from the passing trough
will combine to create more widespread snow. For southern Elbert
and Lincoln Counties, the snowfall forecast was uncertain but 2-6"
is the best estimate. If that were to occur, the strong winds up
to 45 mph that are expected to form later tomorrow morning, will
blow the snow around and could create low visibility and hazardous
travel conditions. Therefore, a Winter Weather Advisory was
issued for that area from midnight to 11 AM.

The mountains will continue to see light snowfall throughout the
night. Given the precipitation currently occurring on the Grand
Junction radar, generally 2-4" of additional snow accumulation
will fall by midday tomorrow.

Subsident flow will quickly move over our forecast area by midday
Friday which will put an end to the snow. It will be a chilly and
breezy day compared to what we have gotten used to in Denver this
winter. Wind chills will be in the low 20s throughout the daylight
hours and will fall to the single digits Friday night. Air
temperatures will fall to the teens across the plains and to the
single digits in the foothills and mountain valleys Friday night.

Saturday through Tuesday will have dry weather with warming
temperatures. Highs across the plains will reach the 50s on Sunday
and some 60s are possible on Monday and Tuesday. The next chance
for precipitation will come Wednesday into Thursday. A couple of
shortwave troughs within the northwesterly flow aloft could bring
snow to the mountains and a mix of snow and rain to the plains.

&&

.AVIATION /12Z TAFS through 12Z Saturday/...
Issued at 451 AM MST Fri Jan 9 2026

Light snow showers continue early this morning across the TAF
sites. The current wave of lower ceilings and light snow is
expected to be the final push of this system, with snow potential
expected to diminish between 13-15Z as drier air moves in from the
north, and ceilings seeing significant improvements by 17Z, with
VFR conditions expected to return between 18-21Z across the TAF
sites. North winds are expected to increase by 14Z, with gusts
between 20-25 kts expected through the afternoon before turning to
drainage between 4-5Z.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 AM MST this morning for COZ031-
033-034-036-041-047.

&&

$$

UPDATE...9/Heavener
DISCUSSION...Danielson
AVIATION...9

NWS BOU Office Area Forecast Discussion