935
FXUS65 KBOU 181203
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
503 AM MST Sun Jan 18 2026

.KEY MESSAGES...

- Light snow expected this evening through early Monday morning,
  possibly leading to poor travel conditions for Monday morning.

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

&&

.UPDATE...
Issued at 305 AM MST Sun Jan 18 2026

Only a few minor changes to the forecast for today and tomorrow.
Winds were increased in portions of the foothills for the next
couple of hours. The stronger winds currently extend as far east as
KBJC, with gusts around 30 to 40 mph. These gusty winds are expected
to retreat westward into the mountains starting around 4AM. A cold
front will move south out of Canada early this morning, moving into
northern Colorado by this evening. Snow chances start in our
northern plains and mountains around 5PM, increasing and pushing
south as we go into the overnight hours. Models continue to show
decent conditions for the development of light snow today, including
weak frontogenesis, lift from the right entrance region of the upper
jet, increasing moisture in the column, and weak upslope flow.
Because of this, confidence has increased in the potential for light
snow accumulations across the I-25 corridor, metro, and eastern
plains. PoPs were increased starting Sunday afternoon and continuing
into late Monday morning, with a peak in chances overnight Sunday
into early Monday. Snow amounts remain generally the same as the
previous package, with amounts around a trace to 2 inches for much
of our area. I will say, there is still quite a bit of uncertainty
in the potential development and location of heavier snow bands. If
a heavier snow band does develop, we could see localized areas with
higher snow amounts (closer to 3 inches). Denver snow totals are
currently sitting around half an inch to an inch for this event,
which could lead to difficult travel conditions for the Monday
morning commute.

&&

.DISCUSSION /Through Saturday/...
Issued at 215 PM MST Sat Jan 17 2026

Exceptionally dry air has moved across our forecast area with dew
points down to -19 F across the plains. Despite the cool
conditions, relative humidity has fallen to as low as 11 percent.
Conditions have met red flag criteria across the majority of the
plains. Winds will weaken quickly right before sunset and the Red
Flag Warning may be able to be canceled a bit early.

Brief ridging aloft will move over Colorado on Sunday leading to a
mild day. Downslope winds will allow high temperatures to reach
the low 50s across the plains.

A quick-moving through will pass through northeast Colorado late
Sunday night. There will be PVA and low level frontogenesis that
will combine to create lift. A band or two of snow will form
across northeast Colorado late Sunday evening. This system will
not have much moisture with it but snow ratios will be favorable
due to a relatively deep dendritic growth zone. NBM had PoPs and
QPF that were too low so those values were increased. The
forecast snowfall is between a trace and 2" for the majority of
the I-25 corridor, eastern plains, and foothills. The mountains
may see a bit more snowfall and the far northeast plains by
Nebraska may see no accumulation. The snow may lead to poor
travel conditions Monday morning due to snow-covered and slick
roads.

The northwesterly flow aloft will continue throughout the rest of
the work week. Minor shortwave troughs may bring very light snow a
couple more times throughout the week. Temperatures will go back
and forth between 5-10 F above normal to 5-10 below normal. No
other significant impacts are expected.

&&

.AVIATION /12Z TAFS through 12Z Monday/...
Issued at 438 AM MST Sun Jan 18 2026

Winds will generally stay from the west through mid morning,
before turning more NW. In the late morning to early afternoon,
winds will turn more northerly, eventually turning to the ENE by
the late afternoon. Lower ceilings will follow the easterly wind
shift, with the potential for MVFR CIGs by 06Z. Snow showers could
start at KDEN as early at 03Z, but the most likely snow timing
for all TAF sites will be between 6Z and 12Z. Ceilings and
visibilities will drop to MVFR thresholds as snow showers move
over the area. Right now, widespread IFR conditions do not look
likely, but if a heavier snow band sets up near the airport, we
could see visibilities temporarily drop to IFR.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...AP
DISCUSSION...Danielson
AVIATION...AP

NWS BOU Office Area Forecast Discussion