744
FXUS65 KBOU 011138
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
538 AM MDT Wed Apr 1 2026

.KEY MESSAGES...

- Mountain snow will continue through this evening, with travel
  impacts for higher passes during heavier snow.

- Numerous rain showers are expected on the plains this afternoon
  and evening. Isolated thunderstorm or two possible. Still mainly
  light precipitation amounts.

- A brief warm up Thursday, with potential for locally critical
  fire weather conditions.

- Windy and cooler Friday with another round of snow for the
  mountains. Plains look to be dry (80% confidence).

&&

.DISCUSSION /Through Tuesday/...
Issued at 1138 PM MDT Tue Mar 31 2026

Satellite shows a large plume of deepening moisture across the
western U.S. for a change...something we have seen very little of
this winter season and early spring. Integrated water vapor
transport (IVT) was more than impressive, reaching 6-8 standardized
anomalies when compared to climatology. In other words, this is
extremely rare event for this time of year (but also attributable
to the unseasonably warm airmass able to hold more water than
typical). At any rate, the bulk of this moisture plume will set
its sights on the mountains of western and southern Colorado,
with the northern mountains being more sheltered in southwest flow
aloft. There is still moderate synoptic scale lift and slight
instability ahead of the trough moving across the Great Basin.
Therefore, we still expect several inches of wet snow for the
mountain areas and thus a continuation of the Winter Weather
Advisory for the northern mountains above 9,000 feet. Locally a
foot or more is expected in the Park Range north of Rabbit Ears
Pass. Much of the Colorado mountains will finally benefit from a
high water content precipitation event, and the snowpack could use
every drop/flake it sees. Meanwhile, mountain valleys will
likely see a rain or rain/snow mix for this event, changing over
to all snow late this afternoon and evening as the upper level
trough and cold front arrive. While there may be a brief burst of
convective snow for the high country with this feature, there is
rather pronounced drying behind it so expect snow to decrease by
late evening, with only scattered lighter showers lingering in the
high country overnight.

On the plains, we`ll be fighting deep downslope flow for most of
this period so a significant precipitation event is not expected.
But by afternoon, surface cyclogenesis occurs along the Palmer
Divide into southeast Colorado, limiting our downslope component
and perhaps just enough to bring a brief period of shallow
upslope. At the same time, the better dynamics will be arriving
ahead of the upper level trough, and combined with weak
instability and abundant mid/upper level moisture we still expect
a round of showers/isolated thunderstorms to develop along the
Front Range/I-25 Corridor and move northeast across the plains
through the evening. While most of these will be light, the
convective and rich moisture components will allow a few
showers/isolated storms to produce a brief period of moderate to
heavy rain. Ensembles are still consistent that most areas will
only average 0.05-0.20 inch across the I-25 Corridor, but the
isolated heavier showers could put down 0.3 or 0.4 inch. Those
amounts will increase as you travel northeast across the plains
where the rain showers are expected to last longer into the
evening as the storm system intensifies in the Central Plains. A
few spots over the northeast plains could see a half inch (30-50%
chance) east of Sterling and Akron.

Behind this storm system, there will be a sharp but short break
Thursday. That break will feature flat ridging and lee troughing,
so expect breezy conditions and a quick warmup back to above
normal temperatures. With that, depending on how much
precipitation occurs tonight, fire weather conditions may be
ramping up again. The most prone areas would be south and
southeast of Denver across the Palmer Divide and adjacent plains.
However, with possibility of rainfall we`ll keep the existing fire
Weather Watch confined to eastern Elbert and Lincoln Counties
where less precipitation and more wind/lower RH is expected.

The next weather disturbance arrives by Thursday night. It`s
almost unanimous now that the center of the upper low tracks well
to our north through Wyoming, meaning strong westerly flow aloft,
mountain snow, and mainly dry weather for the plains. It will
also be turning colder and windy with strong low/mid level
gradients expected. Thus, there is potential for more fire weather
concerns for the lower elevations on Friday. Temperatures will
also be colder in the mountains, so despite less snowfall we do
anticipate more travel impacts for the high country Thursday night
potentially lingering through Friday.

For the weekend into early next week, ensembles suggest mainly dry
weather and gradual warming. However, we will be open to backdoor
cold fronts so one or two of those days should be cooler.

&&

.AVIATION /12Z TAFS through 12Z Thursday/...
Issued at 538 AM MDT Wed Apr 1 2026

Stronger south winds just east of the Denver area are producing a
Denver cyclone/shear zone. Winds at DEN have just shifted to the
northwest. At APA winds are southerly, but northwest winds are
not far off to the west. Northwest to north winds are expected to
then prevailinto the afternoon and early evening (18-02Z),
though outflow from convection could disrupt this pattern. Towards
06Z Thursday, winds transition to a southerly drainage
direction.

Lift from the upper level system will move across eastern
Colorado, including the Denver area after 18Z. Numerous showers
are expected to form after 18-19Z with a few weak thunderstorms
also possible. Ceilings are expected to fall to around 4000-5000
feet under the showers/storms. The threat of rain begins to
decrease after 01Z Thursday. Clouds will start to scatter after
06Z with mostly clear skies expected by 12Z Thursday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 9 PM MDT this evening for COZ031-
033-034.

Fire Weather Watch from Thursday afternoon through Thursday
evening for COZ246-247.

&&

$$

DISCUSSION...20
AVIATION...12

NWS BOU Office Area Forecast Discussion