National Weather Service Forecast Discussion

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262
FXUS65 KBOU 310842
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
242 AM MDT Sun May 31 2026

.KEY MESSAGES...

- Drier weather will prevail for all areas on Sunday.

- A chance for strong thunderstorms returns for Monday and Tuesday
  afternoon, with locally heavy rain possible on Monday.

- Trending a little warmer and drier by the end of the week.

&&

.DISCUSSION /Through Saturday/...
Issued at 222 AM MDT Sun May 31 2026

Today should be the quietest day of the upcoming forecast period.
The trough axis responsible for Saturday`s storms has lifted into
central Wyoming, leaving most of Colorado in a drier zonal flow.
It`s possible enough mid-level moisture remains for a few weak,
high-based showers this afternoon across the mountains, but little
else is in the forecast during the day. Temperatures look to end
up near or a little above normal across the plains.

We should see a transition to southwesterly flow aloft on Monday
as weak ridging builds across the southern Great Plains, while the
previously mentioned trough remains nearly stationary over
Montana. Gradual moisture advection is expected as easterly
surface winds develop Monday morning, leading to a broad area of
instability developing over eastern Colorado by the early
afternoon. However, it`s still a little too far away to get into
any meaningful details given the uncertainty in the low-
level/boundary layer moisture profile. Like yesterday, both CAMs
and global models have a rather large spread in Td forecasts
across most of eastern Colorado. Assuming we do get sufficient
moisture... forecast soundings would favor a few supercells with
sufficient instability, slightly curved hodographs, and ample deep
layer shear. For now, the highest probability of severe weather
is still east of I-25 (roughly along/east of a line from Limon to
Fort Morgan), though confidence is rather low at this time.

The synoptic pattern doesn`t change significantly on Tuesday, with
a continued easterly surface flow slowly advecting moisture into
the region. There would once again be at least a conditional
severe threat across most of the lower elevations, though issues
with stratus/capping would also be possible.

By mid-week, the cutoff low over Montana finally lifts off to the
north, while the Great Plains ridge slowly drifts east, leaving
most of Colorado in rather weak flow aloft. Wednesday should still
see scattered showers and a few storms across the Front Range and
plains with enough moisture/instability around, with lowering
severe chances as shear magnitudes decrease substantially.

A slow drying and warming trend still looks likely for the latter
half of the week, but isolated showers/storms are still expected
across the higher elevations. Temperatures should also warm a bit
in this period, with forecast highs back in the mid/upper 80s
across the plains.

&&

.AVIATION /06Z TAFS through 06Z Monday/...
Issued at 1134 PM MDT Sat May 30 2026

VFR conditions are expected through the TAF period. Some gusty WNW
winds will persist at BJC for a couple of hours, with light and
variable winds at DEN/APA... before drainage takes over by 08-09z.
A gradual clockwise turn is expected on Sunday, with WNW
developing during the morning hours before eventually becoming
more N/NE in the afternoon. Another slow turn to drainage is
likely near or after 06z Sunday night.

There is a slight chance of a weak high-based shower Sunday
afternoon but not enough to include in the TAF at this time. No
ceiling or visibility concerns are anticipated.

&&

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

&&

$$

DISCUSSION...Hiris
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion