National Weather Service Forecast Discussion

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859
FXUS65 KBOU 181919
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1219 PM MST Wed Feb 18 2026

.KEY MESSAGES...

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

- High winds 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 snow
  squall or two is possible (30-40% chance) late this afternoon
  and evening.

- Light accumulating snow of a couple inches is likely (60-80%)
  over the far northeast corner of the state tonight - Thursday
  morning. There is a small chance (10-30%) of heavier snow up to
  6" near the Nebraska border.

- 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 Wednesday/...
Issued at 1207 PM MST Wed Feb 18 2026

Water vapor imagery shows some Pacific moisture extending across
much of western and central Colorado. The imagery shows a strong
shortwave trough just south of Salt Lake City and many Snow Squall
Warnings have been issued in the state of Utah due to the strong
winds and intense but brief snowfall there. This shortwave will
move eastward throughout the day today and snow will increase in
coverage and intensity in the Colorado mountains as a result. The
Winter Storm Warning and Winter Weather Advisory for the mountains
of our CWA were continued with 5-10" of additional snowfall in the
Park Range and 3-5" of additional snowfall across the rest of the
mountains. There is some concern that a snow squall or two could
develop over the I-70 mountain corridor late this afternoon or
early evening given what is occurring farther west. However, high
resolution models have not been particularly excited about the
potential for heavy snow during this period and the lapse rates
will decrease after sunset so the hope is that we will avoid
having to issue Snow Squall Warnings.

Otherwise, the plains have been breezy with low relative humidity
this morning and temperatures are expected to increase slightly
this afternoon. The windiest spot has been Limon with gusts up to 35
mph there. It appears the Red Flag Warning will verify for Elbert
and Lincoln Counties so that was left unchanged. Areas farther
north will likely not have the winds to warrant the issuance of a
Red Flag Warning so the warnings were not expanded.

Tonight, the aforementioned shortwave trough will slow its
eastward progress over northeast Colorado. There is growing
confidence that a surface low will form over northeast Colorado
with a TROWAL extending northwestward from the low. Given healthy
frontogenesis around 700 mb and a push of cold air at the surface,
light to moderate snow will likely (60-70% chance) form to the
north and east of Fort Morgan. At this time, 0.5-2.5" of snow is
in the forecast with the heaviest amounts in Logan County. There
is some concern that the forecast is trending toward a higher end
snow solution given the low is forecast to develop a tad farther
south than previous forecasts. The higher end snow solution could
end producing up to 6" of snow in the far northeast corner of the
state and with gusty winds around 35 mph, blowing snow and low
visibility would be possible. No highlights were issued at this
time but future shifts may have to take action and issue Winter
Weather Advisories in the far northeast corner.

The next threat to our forecast area is high winds late this
evening through tomorrow morning. On the backside of the trough, a
mountain wave will setup over the foothills beginning between 8-9
PM tonight. While the mountain wave will be brief, the setup
looks solid for high winds given the strong inversion and mean
state critical layer that show up on forecast cross sections. The
High Wind Watch was upgraded to a High Wind Warning with gusts up
to 75 mph possible mainly in the foothills and cities like Boulder
and Golden.

Another shortwave trough will move into Colorado on Friday which
will bring QG ascent to our forecast area. This should lead to
another moderate snow event in the mountains and advisories may be
needed for travel impacts. Model guidance has continued to show
light snowfall across the I-25 corridor and eastern plains Friday
afternoon into Friday evening. However, the snowfall in the models
remains very light. The ECMWF ensembles show a high chance of snow
(~85% of ensemble members have snow), but light amounts (the
majority of members have 0.5-1.5" of snow). Travel impacts could
occur during the evening commute on Friday but these impacts will
be relatively light.

The weekend will be dry with initially cold conditions.
Temperatures will increase substantially on Monday and into
Tuesday when the 70s may return to the plains. Saturday through
Monday should not have any weather impacts. By Tuesday, the chance
for elevated to critical fire weather conditions will return.

&&

.AVIATION /18Z TAFS through 18Z Thursday/...
Issued at 1049 AM MST Wed Feb 18 2026

Southwest winds are currently gusting up to 25 kts at all
terminals, and are expected to continue through the afternoon with
slightly higher gusts up to 30 kts at BJC. In the next few hours,
scattered rain/snow showers will begin to spill off the foothills
through 01/02Z. However, it is still uncertain whether anything
will reach the ground. For this reason, have kept the PROB30 as is
for all TAF sites. With the passage of precipitation, expect lower
ceilings down to 6000 ft, with the potential for 3000-4000 (low
confidence on the lowest ceilings).

This evening/tonight, a mountain wave may develop and bring gusty
westerly winds to the terminals. BJC will see the strongest winds,
gusts likely up to 45-50 kts at times, particularly between 05Z
and 11Z. DEN and APA may see intermittent westerly wind gusts up
to 25 kts. There is some uncertainty with how the winds evolve
during this timeframe. Most likely, they will end up with light
drainage overnight, however there is a chance (~40%) that
westerly-to- northwesterly winds persist.

Tomorrow morning, a cold front is progged to reach DEN by 15/16Z,
which will bring northeasterly winds. Behind the front, expect
winds to transition to the northwest.

&&

.FIRE WEATHER...
Issued at 1207 PM MST Wed Feb 18 2026

The plains have been breezy with low relative humidity this
morning and temperatures are expected to increase slightly this
afternoon. The windiest spot has been Limon with gusts up to 35
mph there. It appears the Red Flag Warning will verify for Elbert
and Lincoln Counties so that was left unchanged. Areas farther
north will likely not have the winds to warrant the issuance of a
Red Flag Warning so the warnings were not expanded.

On Thursday, there will be elevated fire weather conditions at the
base of the foothills during the early morning hours given the
high winds. Minimum relative humidity will drop to around 25% so
no Red Flag Warnings are expected to be issued. During the
afternoon, minimum relative humidity will drop to around 15-20%
across far southern Lincoln County. Winds will gust to around 25
mph there so elevated but not critical fire weather conditions are
expected.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 PM MST this evening for COZ030-
032.

Winter Storm Warning until 5 AM MST Thursday for COZ031.

Winter Weather Advisory until 5 AM MST Thursday for COZ033-034.

High Wind Warning from 8 PM this evening to 7 AM MST Thursday
for COZ035-036-039.

Red Flag Warning until 7 PM MST this evening for COZ246-247.

&&

$$

DISCUSSION...Danielson
AVIATION...MAI
FIRE WEATHER...Danielson

NWS BOU Office Area Forecast Discussion