National Weather Service Forecast Discussion

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361
FXUS65 KBOU 170958
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
258 AM MST Sat Jan 17 2026

.KEY MESSAGES...

- Areas of light snow/flurries will come to an end this morning.

- Still gusty winds and critical fire weather conditions over the
  plains east of I-25 today.

- Watching a sneaky light snow event for Sunday night - early
  Monday morning, possibly affecting the Monday morning commute

- Otherwise more tranquil weather Sunday onward. Still dry through
  much of the week ahead.

&&

.UPDATE...
Issued at 258 AM MST Sat Jan 17 2026

Well...a little sneaky light snow/flurries have developed in the
wee morning hours across the plains, despite the very dry low
levels and deep NNW flow in place. There is slight low level
convergence thanks to a weak anticyclone, but appears the main
forcing can be attributed to strong frontogenesis and left exit
region of the next upper level speed max dropping in from the
north. The snow will end early this morning across the plains as
the upper level speed max passes overhead and to the east,
essentially switching us from upward forcing to subsidence and
drying. The last of the snow on the plains will be over the Palmer
Divide-Limon and exit by early-mid morning, while orographics
keep snow showers lingering in the high country until early
afternoon. At least that`s the beneficial news, as we had a couple
bonus inches of snow in the high country to aid the meager
snowpack. Unfortunately, we`re sitting near historic minimums for
this time of year.

With regard to the rest of the forecast and updates, it`ll be
windy across the plains again today (just less windy than
yesterday`s storm). Low/mid level flow is still impressive with
max winds in the mixed layer near 45 kts, so expect gusts as high
50 mph and patchy blowing dust possible in a few spots. The
strong winds and further drying this afternoon will mean more
critical Red Flag conditions despite chilly temperatures. Winds
die off a little quicker late this afternoon and evening as the
low/mid level gradients relax. We do see a mountain wave
developing tonight in/near the Front Range, bringing gusty winds
across most of the foothills and likely onto the nearby adjacent
plains (Highway 93) by late tonight/early Sunday morning.

Attention will then turn to Sunday night and Monday morning, as
models are in better agreement that another speed max and front
with strong mid level frontogenesis will aid our chances of snow.
Those above mentioned parameters are in favorable location for at
least some light banded snowfall stretching from the mountains
across the plains Sunday night into early Monday morning. We`ve
increased PoPs and QPF from the NBM.

&&

.SHORT TERM /Through Saturday/...
Issued at 227 PM MST Fri Jan 16 2026

Strong winds up to 78 mph have created several impacts across our
forecast area today. One of the impacts has been blown over
trucks/vehicles. The strong cross winds have created hazardous
travel conditions and portions of I-25 near the Wyoming border
and I-70 east of Denver have been closed. Another impact has been
blowing dust that is reducing visibility. Some locations have had
visibility reduced to 5 miles across the plains. Finally, the
strong winds and very dry air has created critical fire weather
conditions. A Red Flag Warning continues until 6pm this evening.

These strong winds will weaken after sunset due to reduced mixing.
The High Wind Warning will expire but gusty winds will continue
overnight. Gusts up to 50 mph may still occur especially over the
northeast plains through the night.

The axis of a trough that is approaching Colorado will move
through our forecast area Saturday morning. There will be weak PVA
ahead of this trough, along with upslope flow, that will produce
some mountain snow showers throughout the night. Despite the very
dry air across lower elevations, the Palmer Divide could see some
light snow showers overnight tonight with minimal to no snow
accumulation.

As the trough moves past our forecast area on Saturday, very dry
subsident flow will move in. Dew points could decrease to as low
as -20 F across the far northeast plains. This will lead to
relative humidity dropping to between 12-18%. With gusty winds
continuing, Red Flag Warnings were issued and this is discussed in
more detail in the fire weather section below.

Winds will still gust up to 45 mph on the plains during the day
tomorrow. There will be clearing skies and chilly apparent
temperatures. Winds chills will be in the teens across the plains
throughout the day with wind chills in the 20s across the I-25
corridor.

&&

.LONG TERM /Saturday night through Friday/...
Issued at 227 PM MST Fri Jan 16 2026

Flow aloft is slated to weaken Sunday although will remain firmly
northwesterly, with a secondary jet max over the north-central US
plains sustaining breezy daytime conditions primarily for our
northeast plains, where gusts near 40 mph can be expected. Winds
aside, the subsident flow regime and rising heights will allow
temperatures to rise into the upper 40`s in the plains and low/mid
50`s for the urban corridor.

A cold front will descend into our area Sunday night, bringing
temporarily cooler temperatures for Monday and approximately a 20%
chance for a few light snow showers to most areas early morning. A
localized dusting to 1" wouldn`t be entirely surprising, but there
is limited moisture to work with and most should see little or no
accumulation.

By Tuesday we`ll be back to unseasonably warm temperatures and dry
conditions regionwide with weaker northwest flow prevailing aloft.
Winds look to pick up Tuesday into Wednesday, mainly in the high
country and foothills, as another developing trough over the
northern plains brushes Colorado. Depending on on the spatial
distribution of winds, we may see elevated fire weather conditions
Tuesday (warmest and driest day of the week).

During the latter half of the week, the synoptic pattern favors a
gradual transition towards increasingly zonal flow and some
opportunity for shortwaves and moisture incursions into the high
country. Ensembles remain extremely noisy with regard to timing of
any systems, with additional moderate variance in QPF signals.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1045 PM MST Fri Jan 16 2026

Satellite and radar shows clouds and virga attempting to fill in,
while at the same time an anticyclonic wind pattern has taken
over. Ceilings will likely remain near IMC and hover around 6,000
feet AGL through about 11-12Z, before breaking up as drier air
arrives with the next surge. Until then, there`s just a slight
chance of a few flurries - mainly at KAPA.

With regard to winds, we`ll likely stay a light southerly
component through about 11Z thanks to the anticyclone, before
another northerly surge arrives. This one is showing itself across
northeast Wyoming at the moment. Wind gusts to around 20-25 kts
possible with the initial surge from the north, and then
increasing toward 16Z-17Z with better mixing and gust potential to
32-35 kts at KDEN seems reasonable, while KBJC and KAPA should be
slightly sheltered in northerly flow so will have lighter gusts
there for most of the day. After 22Z, wind speeds weaken and
good confidence they will be light/VRB by 00Z before returning to
fairly normal S/SW winds 02Z and beyond.

&&

.FIRE WEATHER...
Issued at 258 AM MST Sat Jan 17 2026

Today will have similar temperatures and humidity as Friday, and
still strong, gusty winds (just not as ferocious). This means
humidity will fall to between 12-18% across the I-25 corridor and
eastern plains. While winds won`t be as strong as Friday, there
will still be wind gusts to 40-50 mph east of a line from Fort
Collins to Denver International Airport. The lowest relative
humidity and strongest winds will be over the eastern plains, but
there has been some trends of drier air to be farther west by
afternoon. Given the dry fuels, critical fire weather conditions
are expected so the Red Flag Warning was expanded slightly
westward to also include northern Weld County.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 8 AM this morning to 5 PM MST this
afternoon for COZ242-244>251.

&&

$$

UPDATE...20
SHORT TERM...Danielson
LONG TERM...BRQ
AVIATION...20
FIRE WEATHER...20/Danielson

NWS BOU Office Area Forecast Discussion