National Weather Service Forecast Discussion

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921
FXUS65 KBOU 252039
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
139 PM MST Sun Jan 25 2026

.KEY MESSAGES...

- Continued arctic cold to continue through Monday morning.

- Additional snowfall expected through the evening hours. Amounts
  from 1 to 4 inches Urban Corridor and plains with 3-5" for the
  mountains. Expect slippery roads through the mid evening hours.

- Gusty winds in and near the foothills Monday morning may lead to
  areas of blowing snow and poor visibility especially along
  Highway 93.

- Warmer and drier Monday through Wednesday...

&&

.DISCUSSION /Through Sunday/...
Issued at 137 PM MST Sun Jan 25 2026

Surge of colder air moving across the nern plains this aftn will
enhance upslope flow along the I-25 Corridor.  Meanwhile a
disturbance in NNW flow aloft will move across the area thru the
early evening hours.  This feature will have favorable mid level
ascent with it as it moves across.  Thus, will see snow spread from
north to south across the I-25 Corridor, foothills and adjacent
plains.  With rather high snow ratios, snowfall amounts may end up a
bit higher than models are forecasting.  Thus have issued a winter
weather advisory for the I-25 Urban Corridor for later this aftn
thru mid evening as expect slick roads to develop rather quickly.
Snowfall amounts will be in the 2 to 4 inch range with the higher
amounts expected along and west of I-25.  Another are that could see
some decent accumulations are across portions of Lincoln county but
confidence is lower as to where it may exactly occur.  By mid
evening snow will quickly end from north to south and should exit
the far sern plains by midnight.

Temperatures overnight will drop below zero across most of the
plains into the I-25 Urban Corridor and linger through mid morning
on Mon.

On Mon, drier air in NW flow aloft will spread across the area with
downslope flow developing.  This will allow for warmer temps as
readings rise into the upper 30`s to mid 40`s across the plains.
Meanwhile, a mtn wave will begin to develop late tonight and
continue thru Mon aftn.  This will allow for gusty winds to occur in
and near the foothills.  With fluffy type snow cover, expect areas
of blowing snow and reduced visbility in the normal windy areas.
As a result, Highway 93 may have some issues Mon morning.

For Tue, a weak disturbance in NW flow aloft will move across the
area.  Cross-sections show limited moisture in the mtns so will just
keep in a slight chc of snow showers.  Eslewhere, it will be dry
with seasonal temps.

By Wed, an upper level ridge will build into the area with dry
conditions and warmer temps.  Another weak system may affect the
mtns late Wed night into Thu bringing a chc of snow showers.  Across
the plains it will remain dry with above normal temperatures.

For Thu and Fri,  mainly dry NW flow aloft will remain over the
area.  The ECMWF tries to backdoor a shallow surge of colder into
nern CO on Fri.  Meanwhile the GFS keeps this air further to the
east.  At this point, it`s not clear which solution is the best. For
now, have gone with the blended solutions which drops readings
back below normal on Fri across the far nern plains.


&&

.AVIATION /18Z TAFS through 18Z Monday/...
Issued at 1143 AM MST Sun Jan 25 2026

Clouds are slowly beginning to fill in over the Denver metro and
ceilings around 5,000-6,000 feet will likely develop between
19-20Z at all terminals. Winds will begin shifting to the east at
all terminals and will increase in speed around 20Z. There will
be gusts up to 23 knots out of the northeast late this afternoon
as a low pressure system intensifies over central Colorado. Snow
will begin around 21Z and the likelihood and intensity of snow in
the forecast is increasing. The TAF issued has visibility down to
1 SM but brief periods of visibility down to a half mile is
possible. The same goes for ceilings as ceilings around 1,000 feet
are forecast but ceilings could drop to 500 feet. The most
intense snow will fall between 22-02Z but the snow will linger
through 05-06Z.

Low clouds and snow will clear out from north to south across the
Denver metro between 05-08Z tonight. VFR conditions are then
expected for the rest of the TAF period. Winds will become
drainage overnight tonight with light west-northwest flow during
the day Monday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 9 PM MST this evening for
COZ038>040.

Cold Weather Advisory from midnight tonight to 9 AM MST Monday
for COZ038-043.

Cold Weather Advisory until 9 AM MST Monday for COZ042-044>051.

&&

$$

DISCUSSION...RPK
AVIATION...Danielson

NWS BOU Office Area Forecast Discussion