National Weather Service Forecast Discussion

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322
FXUS65 KBOU 180523
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1123 PM MDT Wed Jun 17 2026

.KEY MESSAGES...

- Critical fire weather conditions today across the mountains and
  valleys.

- Elevated fire weather conditions in the mountains and valleys on
  Thursday and Friday with critical conditions expected on
  Saturday.

- Severe storms possible across the far northeast corner on
  Saturday.

- Scattered coverage of showers and storms on Sunday and Monday.


&&

.DISCUSSION /Through Wednesday/...
Issued at 204 PM MDT Wed Jun 17 2026

A cold front moved through the eastern plains of Colorado this
morning reducing the heat today. While many areas in downtown
Denver reached the low 90s this morning before the front, most of
the afternoon will be spent in the upper 80s. The high temperature
forecast was decreased by 2-4 degrees across the plains.

The Red Flag Warning is verifying in the mountains and mountain
valleys as Berthoud Pass is still gusting to 53 mph. No change was
made to the warning.

A secondary push of cooler air will arrive this evening. This will
drop temperatures into the 50s across the plains tonight. It`s
possible that a rain shower or two develops across the far
northeast corner of Colorado tonight but no impacts are expected.

Northwesterly flow aloft will continue on Thursday with a slight
increase in 500 mb heights. High temperatures across the plains
will reach the upper 80s under mostly sunny skies. The mountains
and valleys will be warm and dry again but parameters for fire
weather conditions are marginal so no highlights were issued.

A ridge aloft will move more directly over Colorado on Friday.
Highs will reach the upper 80s again across the plains. There may
be just enough moisture for a few light showers and storms mainly
over the Palmer Divide and southern foothills.

On Saturday, a shortwave trough will move across Colorado during
the latter half of the day. There will be plenty of warm air aloft
and mostly sunny skies over the I-25 corridor and adjacent plains
that temperatures will reach well into the 90s. Out on the
eastern plains, there will be a dryline that sets up near Sterling
to Akron. East of this line, there will be strong instability
with over 3,000 most-unstable CAPE possible. The shortwave and
dryline will provide enough forcing to create strong to severe
storms. The Storm Prediction Center has far northeast Colorado in
a slight risk of severe storms which seems adequate for day 4.

Much more moisture will be in our forecast area on Sunday and
Monday and with a couple of shortwave troughs moving overhead,
scattered showers and storms are expected.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1117 PM MDT Wed Jun 17 2026

VFR conditions expected through the TAF period. With the passage
of the cold front, northeast winds have been gusting up to 35 kts.
Expect winds to gradually weaken in the next hour before speeds
decrease to less than 15-18 kts tonight. Winds will have a more
southerly component in drainage flow overnight, with DEN and APA
being closer to 160-180.

For Thursday, a cyclone is expected to develop, which will likely
keep APA east/southeast throughout the day and BJC more northeast.
Some uncertainty with winds at DEN, however generally expect them
to vary between southeast to northeast as the cyclone moves out of
the area. Speeds should remain under 15 kts.

&&

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

&&

$$

DISCUSSION...Danielson
AVIATION...MAI

NWS BOU Office Area Forecast Discussion