National Weather Service Forecast Discussion

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411
FXUS65 KBOU 261135
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
535 AM MDT Sun Apr 26 2026

.KEY MESSAGES...

- A 20% to 30% thunderstorm coverage this afternoon and evening
  for most of the forecast area.

- Snow showers for the mountains today, mostly this afternoon
  with higher mountain roads and mountain passes becoming slick.

- Cooler and more moist weather pattern expected much of the
  upcoming week. Significant precipitation is not expected but
  any would be welcome.

&&

.DISCUSSION /Through Saturday/...
Issued at 1149 PM MDT Sat Apr 25 2026

Overall, models continue to show a cooler, wetter pattern over the
CWA through the rest of this weekend and much of next week. There
should not be any fire weather concerns.  Currently there are a few
rain showers over the eastern half of the plains and scattered snow
showers over the mountains.

The high temperature in Denver today, 54 degrees, was 9 degrees
below the normal reading for the day and 18 degrees below
yesterday`s high.

Models have west-southwesterly flow aloft for the CWA now through
Monday evening, then a weak upper trough moves across overnight
into Tuesday morning. Behind that trough, strong zonal flow is
progged over us through Wednesday, with speeds of 110-130 knots at
the jet level. Weak upward motion is progged on the QG Omega
fields late day Sunday and again Monday night. The next cold front
is progged across the plains late Sunday night into Monday
morning early.

Concerning convection Sunday afternoon. Surface dew point proggs
show 40s F readings over most of the plains later this afternoon,
with precipitable water values in the 0.50 to 0.70 inch range.
There is some CAPE progged over the CWA this afternoon, up to 600
J/kg over the eastern plains. However, heating could be delayed
Sunday depending on how quickly a potential Stratus deck dissipates.
Will go with 20-40% chances of thunderstorms for much of the CWA
for late day Sunday along with 60%-80% chances of precipitation
for most areas.

For Monday, will leave the high pops for showers going in the
mountains with 70-90 chances, The plains can expect 40%-70% pops
by evening. For late day Tuesday there will be a 40%-70% chance of
showers for the CWA and a 30%-60% for late day Wednesday.

Model QPF fields do not show significant precipitation amounts
Sunday through Wednesday for the CWA, however any water will be
welcomed.  In the mountain zones, snow showers are expected from
Sunday afternoon through Tuesday afternoon.  There will be some
rain mixed in as well as melting during the daylight hours, so
highlights are not warranted at this time.

High temperatures continue to look to be a bit lower than normal
readings Sunday through Wednesday with highs maybe getting into
the lower 60s over the plains some of those days.

Of note, with the cooler than normal period expected through the
rest of this month and the record warmest-ever March in Denver
history, April 2026 will almost certainly be colder than March 2026
was.  The normal monthly mean Denver March temperature is 40.4
degrees. The normal monthly mean Denver April temperature is 47.8
degrees.  The funny thing is, this April may still end up above
normal for the month as it was still 4.4 degrees above normal
through the 24th.

For the later days, Thursday through Sunday, models now show weak
upper troughing over Colorado Thursday and Friday. Moisture is
pretty deep on the cross sections much of that time, there is
upslope over the plains and the QPF fields show decent precipitation
amounts. This is somewhat different than yesterday`s runs indicated.
Upper ridging is progged Saturday and Sunday now with a drier and
warmer airmass both days. Run to run consistency is not very
good.

&&

.AVIATION /12Z TAFS through 12Z Monday/...
Issued at 535 AM MDT Sun Apr 26 2026

A moist airmass will remain over the area through tonight and
Monday. Low clouds have spread across the area, with ceilings 1000
to 2500 feet. Ceilings could fall as low as 500 feet this morning
yet. Wind direction forecast is highly uncertain this morning and
early afternoon due to a Denver cyclone/convergence zone near DEN
and APA. A shortwave trough will lift northeast across Colorado
this afternoon, bringing numerous showers and isolated
thunderstorms. The chance for a thunderstorm at the Denver
airports is 20-30 percent and opted to go with a PROB30 for
thunderstorms 20-23Z Sunday. Ceilings are expected to fall to
3000-6000 feet under the showers and thunderstorms. Isolated
showers will linger past 00Z Monday, and are expected to end by
06Z Monday. There will be another chance for low clouds after 06Z
Monday, but models still vary on the amount of low level
moisture.

&&

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

&&

$$

DISCUSSION...66
AVIATION...12

NWS BOU Office Area Forecast Discussion