802
FXUS65 KBOU 152348
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
448 PM MST Thu Jan 15 2026

.KEY MESSAGES...

- Critical fire weather conditions with 30 to 50 mph wind gusts
  across the plains through this afternoon.

- A cold front will bring strong winds (40-60 mph), colder
  temperatures, and a few snow showers tonight.

- Strong winds (50 to 70 mph gusts) and critical fire weather
  conditions to prevail over northeast Colorado Friday.

&&

.DISCUSSION /Through Thursday/...
Issued at 233 PM MST Thu Jan 15 2026

Water vapor satellite imagery showing a shortwave trough diving
south-southeast across eastern Montana. This wave races
southeastward helping to carve out large upper level low over the
Great Lakes Friday. This will leave Colorado under a strong north-
northwest flow aloft with a 120 knot jet overhead. A strong cold
front associated with the shortwave trough is racing south across
southern Montana and northern Wyoming. Wind speeds are 50 to 60
mph with the cold front passage. We earlier upgraded the High Wind
Watch to a Warning and moved up the timing to mid to late evening
to capture the stronger winds that will accompany the cold front.
The strong winds linger up to a couple hours behind the cold,
then we will see a lull in the stronger winds until Friday
morning. There`s a brief period after midnight where there may be
enough lift and moisture for a few snow showers. Any accumulation
is expected to be light. Subsidence and fierce drying occurs
Friday morning with relative humidity falling into the teens by
late morning and early afternoon. The subsidence and mostly clear
skies will help mix the stronger winds aloft down to the surface,
so we look on track to see 60 to 70 mph wind gusts across the
plains Friday. The 12Z GFS and ECMWF models show the trough axis
and thus the jet has shifted westward by a county or two. This
lines up with 12Z HRRR and the expansion of the High Wind Warning
southwestward. Because of the low relative humidity and strong
winds, upgraded the Fire Weather Watch to a Red Flag Warning for
much of northeast Colorado.

Winds slowly decrease mid to late afternoon Friday, but gusty
north winds linger into the overnight hours. The winds will help
keep the airmass mixed and keep temperatures from getting too
cold. However, the airmass has an arctic origin, so lows are
expected to be in the teens and single digits.

Saturday will see decreasing winds but overall similar dry and
windy conditions. Fire weather conditions may be critical across
the majority of the plains and this is discussed in the fire
weather section below.

A strong trough aloft will move over northeast Colorado with the
axis of the trough moving through our forecast area Saturday
morning. There will be strong subsident flow with very dry air
moving in on the backside of the departing trough. Wind gusts will
reach 45 mph across the plains with the highest values in Weld and
Washington Counties. Temperatures will be cool with highs in the
30s across the majority of the plains. Wind chills will be in the
low 20s to teens especially Saturday evening.

A brief ridge within the northwesterly flow will move across
Colorado on Sunday. This will lead to temperatures warming up
15-20 degrees above the high on Saturday. There will be mostly
sunny and dry conditions.

Another trough moves through on Monday leading to cooler and
windier conditions. There is such little moisture with these
systems that only very light snow will be possible in the
mountains with no impacts from this trough.

The flow aloft will become more zonal during the middle of next
work week leading to mild temperatures. The lack of moisture
continues so no precipitation is expected.

Ensembles by the following weekend have a very large spread with
temperatures. What is noteworthy about the ensembles is that
there could be very cold air coming into Colorado. There`s about a
20% chance that temperatures get below 0 F across our entire
forecast area the weekend of January 24-25.

&&

.AVIATION /00Z TAFS through 00Z Saturday/...
Issued at 439 PM MST Thu Jan 15 2026

Gusty WNW winds are quickly diminishing this evening and that
trend should continue over the next hour or two. Cold FROPA this
evening has sped up just a touch, with a wind shift to the
northeast likely between about 04-05z. Guidance continues to hint
at a brief period of stratus, perhaps as low as a BKN020-035 deck,
for a few hours tonight before drying out by 12z Friday.

Main question beyond that is how winds evolve during the day
Saturday. NW/NNW flow is traditionally difficult to mix down at
BJC and at times APA as those sites are typically sheltered a bit.
On the other hand, most deterministic guidance does develop at
least a period of gusty winds during the afternoon, and the main
change there was to tempo out a period of >30KT gusts. At DEN,
gusty winds are likely again through most of the day, with a few
gusts of >40KT probable after 18z. Winds will be slow to diminish
in the evening.

&&

.FIRE WEATHER...
Issued at 233 PM MST Thu Jan 15 2026

The gusty winds will decrease around sunset with the loss of day
time heating, though it may stay a little breezy during the early
evening hours. A strong cold front races south across the area mid
to late evening with gusts of 40 to 60 mph out of the north when
it pushes through. Moisture increases behind the front with a few
light snow showers possible after midnight. These snow showers
will be light and short-lived as the airmass rapidly dries Friday
morning. Relative humidity readings fall to 15 to 20 percent
during the day Friday. Winds increase quickly Friday morning as
well with gusts reaching 60 to 70 mph over the plains. Strong
winds decrease around sunset Friday, but breezy to windy
conditions may linger through the night in some places.

On Saturday, very dry air with dew points potentially less than
-10F will move into northeast Colorado. Despite the below normal
high temperatures, relative humidity will fall to between 11-16%.
With gusts across the plains up to 45 mph, critical fire weather
conditions are possible. Due to the fire weather highlights in
place today and on Friday, no highlights were issued for Saturday.
However, if the confidence in low dew points increases, a Fire
Weather Watch may be needed for Saturday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 9 AM to 6 PM MST Friday for COZ215-238-240-
242>246-248>251.

Red Flag Warning until 6 PM MST this evening for COZ238>240-
242>246-248-249.

High Wind Warning until 5 PM MST Friday for COZ038-042>045-
048>051.

High Wind Warning from 9 PM this evening to 5 PM MST Friday for
COZ046-047.

&&

$$

DISCUSSION...12/Danielson
AVIATION...Hiris
FIRE WEATHER...12/Danielson

NWS BOU Office Area Forecast Discussion