National Weather Service Forecast Discussion

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661
FXUS65 KBOU 181129
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
429 AM MST Wed Feb 18 2026

.KEY MESSAGES...

- Still breezy/windy with elevated to locally critical fire
  weather conditions today.

- High winds possible in and near the foothills tonight and early
  Thursday morning with gusts to 75 mph.

- Periods of snow and blowing snow in the mountains through early
  Thursday morning will lead to continued travel impacts. A couple
  snow squalls possible (40-60% chance) late this afternoon and
  evening.

- Chance of accumulating snow of a couple inches is increasing
  over the far northeast corner of the state tonight - Thursday
  morning.

- Only a couple showers possible Denver & I-25 Corridor through
  Thursday, but a better chance of light snow Friday afternoon
  and Friday night (60% chance).

- Dry most of the weekend into early next week. Chilly start to  the
  weekend, but a strong warming trend Sunday - Monday.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1117 PM MST Tue Feb 17 2026

A lot to talk about in an active weather pattern through Friday.
We`ll tackle it day by day.

For Wednesday, a moisture laden trough will eject eastward across
the Great Basin, bringing increasing lift, high lapse rates, and
continued off/on snow for the mountains. It`s too bad the pre-
trough flow is southwesterly (which doesn`t favor the northern
mountains outside of the Park Range), otherwise we`d be in the
midst of a heavy snow event. At least most other Colorado
mountains do well in this type of flow pattern. That said, by late
afternoon and evening a reinforcing cold front and trough axis is
expected to arrive. As a result, there will be a threat of snow
squalls for the mountain areas due to favorable ingredients like
high lapse rates and capes of 50-200 J/kg. It`s just that the
strongest mid level front/F-gen might lag the convective
development, so unsure of exactly how organized that threat of
snow squalls will be. Whatever the case, there should certainly
be an uptick in snowfall rates and coverage for a few hours in the
late afternoon and evening especially as winds turn more westerly
with and behind the mid level front. We`ll keep the current
Winter Storm Warnings and Advisories in effect, and even extend
the Front Range Mountains Advisory til 5 AM Thursday to match up
with all the other mountain highlights. Mountain valleys will
remain unchanged (ending at 11 pm Wednesday) since the majority
of the snow after Wednesday evening should be orographically
generated. Meanwhile on the plains, it will be a relatively mild
day Wednesday but breezy to windy weather will bring elevated to
locally critical fire weather conditions. See more in the Fire
Weather section below. Given the synoptic scale lift and rather
unstable airmass, we expect scattered showers to spread off the
higher terrain and across the plains late Wednesday afternoon and
evening as the upper level trough and cold front moves across. We
do think there will be more persistent lift and frontogenesis to
support more widespread coverage of snow over the northern border
area, especially as the upper level trough and support slows on
its trek across the northeast plains. Thus, the potential for an
inch or two of snow is increasing across the northeast corner of
the state (60% chance), with a high end potential (10-20% chance)
of 3-4 inches toward Julesburg and Holyoke, before finally
shifting northeast of the state Thursday morning.

Behind that trough, winds will start cranking up again in/near the
Front Range Mountains and Foothills. Cross sections show at a
minimum a wave induced critical layer, if not mean state critical
layer as the upper level trough elongates Wednesday night. That
gives potential for development of very strong mountain wave induced
winds, despite rather marginal cross mountain flow of only 35-40
kts. Typically, a mean state critical layer can potentially result
in doubling of those magnitudes for peak gusts, so something to
watch. We`ll definitely be increasing the wind forecast to account
for this, and we`ve issued a High Wind Watch for the Front Range
Foothills and nearby adjacent plains Boulder to Golden from 8 PM
Wednesday night - 7 AM Thursday. Winds will also be increasing on
the northeast plains during this time as low level gradients crank
up as low pressure moves through eastern Kansas and high pressure
builds in across the northern High Plains. Peak gusts of 40-55
mph will be likely over most of the northeast plains, and areas
that see accumulating snow could also very well have additional impacts
due to blowing and drifting.

By Thursday night, flat ridging in between the departing shortwave
and the next disturbance moving into the Great Basin should bring a
decrease of mountain snow showers and decreasing winds.

That next shortwave scheduled for later Friday will bring a
potential of a few more inches to the mountains, while most of the
I-25 Corridor and adjacent plains will also have a reasonable
chance (60%) of light snow. There is actually pretty healthy QG
forcing to start on Friday, but by the time the airmass saturates
the upper level trough and forcing start to shear out. Thus the
chances of any accumulations more than an inch or two are rather
small at this time (

NWS BOU Office Area Forecast Discussion