National Weather Service Forecast Discussion

Thornton Weather Forecast   
Today's Forecast Story   
474
FXUS65 KBOU 290012
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
512 PM MST Wed Jan 28 2026

.KEY MESSAGES...

- Light snow for the northern mountains this evening into Thursday,
  with generally minor travel impacts.

- A shallow arctic airmass backdoors into northeast Colorado
  Friday, with a brief chill and chance of light snow. Another
  weak disturbance Saturday but moderating temperatures.

- Dry and mild weather Sunday and Monday.

- Next chance of snow toward Tuesday or Wednesday of next week.

&&

.DISCUSSION /Through Wednesday/...
Issued at 257 PM MST Wed Jan 28 2026

Rather vigorous shortwave over northern Utah this afternoon will
move east across the forecast area this evening. Moisture is
somewhat limited (what`s new), but at least some snow will move
into the mountains this evening and continue into Thursday in
post-frontal orographics. Despite the shallow moisture, healthy
orographics (W-NW at 30 kts) will support 1 to 4 inches of snow in
most mountain areas along and north of the I-70 Corridor, with a
higher end potential around 6 inches in the Park Range. For the
plains, we`ll see downslope flow continue as the mid level front
moves across and surface low pressure moves into the Southern High
Plains. This means breezy but mostly dry conditions will occur
across the plains tonight. Expect a fair amount of virga, and just
a slight chance that a few flurries or a little light snow
reaches the ground - mainly toward the Palmer Divide which isn`t
so negatively impacted by northwest flow.

Moderate subsidence develops late this evening behind the trough
axis, with generally clearing skies expected along the Front Range
toward Thursday morning. Meanwhile, light snow showers will
continue in the higher orographically favored areas of the
mountains, while a band of mid level clouds is anticipated over
the far northeast plains on Thursday. Breezy conditions will
continue through the day with moderate gradients and mixing, with
gusts up to 35 mph over the eastern plains.

There will be lingering moisture trapped in the mountains in
northwest flow through Friday, enough for at least scattered light
snow showers but little in the way of accumulations or impacts is
expected. Meanwhile, the next surge of arctic air behind a
shortwave dropping southward across the Great Lakes will offer up
a glancing blow of arctic air to northeast Colorado. We are almost
certain there will be enough push to reach Denver, with a chance
of light snow or flurries behind the front. Once again, it won`t
be much with only a dusting to around one inch of fluff possible
on the eastern plains. We would lean toward the colder guidance in
this scenario with overnight lows in the single digits to lower
teens by Friday night. This does not appear to last long, however,
as most model systems bring a quick warmup into Saturday. Again,
we`d still lean toward the colder guidance given shallow
intrusion, but the Denver metro area would be more favored to see
complete erosion and a mild day already by Saturday. Another weak
wave is advertised to arrive later in the day/evening, so we can`t
rule out a few more mountain snow showers (scattered - 40%
chance) or even some light snow (20-30% chance) over the
northeastern corner of the state.

Ensembles support strong ridging and warming across the entire
forecast area Sunday through Monday. High temperatures will warm
to much above normal levels, with high temperatures of 60F likely
(>60% chance) across the I-25 Corridor and plains.

The next weather disturbance is still slated to arrive by Tuesday
and/or Wednesday. However, there continues to be a considerable
amount of uncertainty regarding the evolution of this trough.
We`ll maintain the forecast of cooler temperatures and a chance of
snow, but again this looks like mostly a light precipitation
event.

&&

.AVIATION /00Z TAFS through 00Z Friday/...
Issued at 440 PM MST Wed Jan 28 2026

VFR conditions are expected through this TAF package. Gusty winds
will continue at KBJC through much of the evening, before
weakening after midnight. Variable winds will continue at KDEN and
KAPA for a couple more hours, then winds will turn more to the WNW
for the overnight period. KDEN will have the potential for gusty
winds this evening between 3Z and 7Z, as light showers produce
virga around the area and winds increase aloft. Tomorrow morning
winds will generally be from the NW around 6 to 10kts, until winds
increase around 17Z to 19Z from the NW, with gusts between 17kts
to 25kts for the afternoon.

&&

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

&&

$$

DISCUSSION...20
AVIATION...AP

NWS BOU Office Area Forecast Discussion