National Weather Service Forecast Discussion

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161
FXUS65 KBOU 101802
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1202 PM MDT Wed Jun 10 2026

.KEY MESSAGES...

- Elevated to critical fire weather conditions across the plains
  this afternoon and evening with warm, dry, and breezy conditions.

- A brief cooldown for Thursday behind this evening`s cold front.

- Critical fire weather conditions likely across the high country
  Friday and Saturday.

- A more substantial cooldown starting Sunday, with a better
  chance of showers and storms.

&&

.DISCUSSION /Through Wednesday/...
Issued at 1138 AM MDT Wed Jun 10 2026

Relatively quiet conditions are noted across the forecast area
this morning, with just a few clouds noted on satellite. Once
again, gusty westerly winds are having a difficult time mixing
down into the I-25 corridor and plains, with a diffuse/broad
Denver cyclone still firmly entrenched across the metro. While
gusty winds have been slow to develop, model guidance is insistent
that this will happen sometime in the next couple of hours. This
includes the NAM/3km NAM whose boundary layer schemes typically
under-mix in weakly subsident patterns. While the Red Flag
Warning is pretty borderline/marginal, it did not seem necessary
to make any changes to that highlight.

Next up on the forecast agenda is well-defined cold front moving
through the region late this evening into the overnight hours.
Guidance still moves this through the Denver area by 10PM to
midnight tonight... and will keep temperatures tomorrow about
5-10F cooler across the plains with some modest cooling across the
high mountain valleys as well. The post-frontal airmass is very
dry and Thursday should be mostly sunny across the forecast area.

Zonal flow is expected to persist for Friday and Saturday, with
the mid-level thermal ridge expanding back into the state. For the
plains, this will mean a continued period of warm and very dry
conditions. Across the higher elevations, the mid-level flow is
expected to remain strong enough for gusty winds each afternoon...
and combined with the hot/dry airmass will lead to increasing fire
danger. See the Fire Weather discussion below for additional
details.

A pronounced (albeit brief) pattern change is expected to end the
weekend, as a strong shortwave trough dives in from the Northern
Rockies. Widespread showers and a few thunderstorms are forecast
Sunday afternoon and evening behind a surface cold front, with
decent changes of meaningful rainfall (30-60% chance of >0.10")
across most of the forecast area. Temperatures will be
substantially cooler... with forecast highs in the upper 60s to low
70s on both Sunday and Monday.

Forecast certainty decreases by next week. A large ridge is
expected to begin building to our southwest, while a couple
shortwaves reinforce the northwesterly flow across most of the
Central/Northern Great Plains. Our forecast area looks to be stuck
somewhere in the middle of these two features, leading to a rather
uncertain temperature forecast. Most ensemble guidance favors a
couple of warmer days during the middle of next week, with
deterministic forecasts wobbling back and forth a bit from run to
run.

&&

.AVIATION /18Z TAFS through 18Z Thursday/...
Issued at 1138 AM MDT Wed Jun 10 2026

VFR conditions expected through the TAF period. Winds are currently
VRB and ranging between 07-13 kts at all TAF sites due to a cyclone
that formed. With this cyclone, westerly winds have yet to make it
to all terminals. There is still some uncertainty on the exact
time west winds will make it (could be in the next 2-4 hours) and
will depend on the evolution of the cyclone currently located
south of KDEN. When the west winds do occur, expect gusts up to 32
kts through the early evening.

A cold front should move through the terminals between 04Z-07Z
tonight, with gusts up to 25 kts behind it. By Thursday morning,
expect winds to turn more easterly, generally between 08-12 kts as
an anticyclone develops north of the airports.

&&

.FIRE WEATHER...
Issued at 1138 AM MDT Wed Jun 10 2026

Critical fire weather conditions are likely across at least a few
portions of the plains this afternoon. Near critical fire weather
conditions have already been observed from the Cheyenne Ridge into
far northeastern Colorado this morning. Gusty westerly winds
should become more widespread across the lower elevations this
afternoon as better mixing develops. Recent forecast trends have
held onto just a little bit more moisture than previously
expected... and while there may be less overlap in wind/RH
compared to previous forecasts, we did not opt for any changes to
the existing Red Flag Warning today.

Critical fire weather conditions are likely to develop across
portions of the high country by Friday and Saturday. 30-40kt
700-500mb flow in a broadly subsident regime combined with a very
dry airmass and above normal temperatures should lead to
widespread elevated to critical conditions there... with weaker
winds limiting fire danger across the plains. Although fuel
susceptibility appears to be somewhat mixed across the mountain
valleys, we`ve issued a Fire Weather Watch for North Park and
Middle Park where the flow aloft is strongest. Additional
headlines may be needed both Friday and Saturday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Friday morning through Friday evening
for COZ211-213.

Red Flag Warning until 8 PM MDT this evening for COZ240>248-250-
251.

&&

$$

DISCUSSION...Hiris
AVIATION...MAI
FIRE WEATHER...Hiris

NWS BOU Office Area Forecast Discussion