National Weather Service Forecast Discussion

Thornton Weather Forecast   
Today's Forecast Story   
115
FXUS65 KBOU 211119
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
419 AM MST Fri Feb 21 2025

.KEY MESSAGES...

- Light snow will gradually end by mid morning over the I-70
  mountain corridor, southern foothills and along the I-25
  Corridor from Denver southward across the Palmer Divide. This
  will create hazardous travel conditions and affect the morning
  commute.

- Mainly dry this afternoon with moderating temperatures across
  the plains.

- Warming trend on the plains into the weekend and early next week.

&&

.SHORT TERM /Through Tonight/...
Issued at 239 AM MST Fri Feb 21 2025

Small, but potent upper level storm system, brought heavy snow to
the foothills last evening and overnight. This feature was over
east central CO early this morning and will gradually move
eastward into wrn Kansas by midday.

Lingering snow will continue thru 12z over the I-70 mtn corridor,
srn foothills and along the I-25 Corridor, from Denver southward
across the Palmer Divide. Snow should gradually diminish by mid
morning as drier air advects in from the north. For this aftn, it
will be dry in most areas, however, can`t rule out a few snow
showers in the mtns due to lingering low level moisture. Highs
this aftn will be warmer as readings rise into the mid 30s to
lower 40s across nern CO.

For tonight, dry NW flow aloft will be over the area.  Overnight
lows across the plains will begin to moderate back to more seasonal
levels.

&&

.LONG TERM /Saturday through Thursday/...
Issued at 239 AM MST Fri Feb 21 2025

Significantly warmer and drier conditions are expected Saturday with
slightly above normal temperatures as a ridge starts to build
over the region. Weak westerly to southwesterly winds at the
surface will allow downslope flow to warm up the plains, however
snow packed areas, like the Palmer Divide, may struggle to reach
the forecasted low 50s. The warming trend will continue into early
next week with broad upper level bridging over the state. Sunday
through Tuesday could see temperatures in the 60s each day due to
downslope winds.

A weak shortwave trough Sunday evening into Monday could bring light
snow showers to the northern portions of the mountains. There is
very little moisture associated with this system, so accumulations
will be light. The high country could see 45+ mph wind gusts
overnight Sunday into Monday, with the ridgetops seeing the
strongest gusts. This will cause blowing snow from the foothills to
the mountains.

A stronger shortwave trough will track sometime midweek bringing
another chance for orographic snow showers for the mountains.
However, it will be too dry for the plains to see anything. A cold
front will drop temperatures to the 50s for the plains and bring
widespread gusty winds. The Front Range could see 45+ mph wind gusts
and the plains could see 35+ mph gusts. Looking towards the end of
the week, warmer temperatures reappear as there is an agreement in
models that a ridge will build over the western United States.

&&

.AVIATION /12Z TAFS through 12Z Saturday/...
Issued at 415 AM MST Fri Feb 21 2025

Light snow should gradually end by 14z or 15z this morning.
Ceilings will mainly be MVFR but can`t rule out IFR at APA
for an hour or so. Visibility will be IFR at times. Winds
will be light and variable. After 15z ceilings will rise to
around 5000 ft with no visibility issues. By 18z ceilings
will sct out with VFR conditions this aftn and tonight.  Winds
will be mainly from the north this aftn and then gradually shift
to drainage by early evening.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 8 AM MST this morning for COZ034-
037-039>041.

Winter Storm Warning until 8 AM MST this morning for COZ036.

&&

$$

SHORT TERM...RPK
LONG TERM...Ideker
AVIATION...RPK

NWS BOU Office Area Forecast Discussion