National Weather Service Forecast Discussion

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813
FXUS65 KBOU 111915
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
115 PM MDT Thu Jun 11 2026

.KEY MESSAGES...

- A brief cooldown today behind this morning`s cold front.

- Elevated to near critical fire weather conditions likely on
  Friday and possible on Saturday across the high country.

- Trending cooler for Saturday behind a cold front.

- Low to medium chance (10% to 60%) of showers and storms Sunday
  through Monday.

&&

.DISCUSSION /Through Thursday/...
Issued at 1251 PM MDT Thu Jun 11 2026

The cold front last night has dropped temperatures below normal this
afternoon, with much of the plains sitting around 10 degrees
cooler than this time yesterday. Late this evening and overnight,
breezy north/northeast surface winds will potentially bring in
some smoke from an active fire in NW Nebraska this evening. Smoke
concentration should be low, so impacts are expected to be
minimal, but conditions could become hazy and smell of smoke.

Mid level flow will become more zonal tomorrow. Winds will be out
of the west around 25 to 40kts at 600mb. This will create wind
gusts around 30 to 45 mph in the higher terrain Friday morning and
afternoon. Winds won`t be quite as gusty across the plains, but
we could still see occasional W/NW wind gusts around 20 to 30mph
in the early afternoon across our eastern counties. Downsloping
winds and plenty of sunshine will bring temperatures back above
normal for Friday, with highs reaching into the 80s to low 90s
across the plains. Breezy winds and dry conditions could lead to
some elevated to near critical fire weather concerns for Friday.
The Fire Weather Watch was cancelled due to reports of green up
and higher fuel moisture which will help limit the potential for
rapid fire spread. However, RHs will still drop into the low teens
with strong gusts in portions of the mountains. Critical fire
weather conditions across the plains will be too spotty and short
lived for an RFW tomorrow, due to the timing and location of the
stronger winds, but RHs will be very low.

Temperatures for Saturday continue to trend cooler. At mid and upper
levels, a strong low will sit north of the great lakes, with a
shortwave rotating through the flow aloft towards/north of our
area this weekend. The main difference with this round of models
runs is the strength of the cold front on Saturday. Models
generally have it moving through late Friday through early
Saturday, putting breezy north/northeast winds across the plains
for almost all Saturday. This will keep high temperatures closer
to the mid to upper 70s across the plains Saturday afternoon. The
cold front looks to be reinforced late Saturday as high pressure
builds in from the north at the surface. This along with increased
cloud cover will keep temperatures on the cooler side again for
Sunday, with highs in the 60s and low 70s across the plains.

Precip chances during this time are a bit tricky. Models are backing
off on widespread precip chances for the weekend. Models are
trending towards a less pronounced shortwave with a more northern
track, which will limit the amount of upper level support we have
for precipitation. It looks like there may be a secondary weak
disturbance late Sunday into Monday, providing some low to medium
rain chances. Increased moisture and dew points on Monday along with
some weak surface convergence could allow precip to continue into
late Monday morning and potentially Monday afternoon. Right now,
there`s about a 20% to 30% chance that the Front Range and Palmer
Divide area will see 0.1 inches of rain Monday morning into
Monday afternoon, with lower chances elsewhere.

The thermal ridge over the west coast will start to push eastward
and strengthen on Tuesday, increasing temperatures across our area.
By Wednesday 700mb temps will reach into the teens to near 20
degrees Celsius. The 25th to 75th maximum temperature percentiles
for Wednesday currently range from the mid 90s to the low triple
digits for much of the plains.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1113 AM MDT Thu Jun 11 2026

VFR and no convection expected near the terminals through Friday.
The focus is on the winds. NE winds will continue all afternoon,
gradually turning east by 22-23Z, then south at APA and DEN after
07/08Z. Drainage winds at both DEN and APA will be stronger than
usual, 10-13KT at APA and 14-17KT at DEN. By 14-15Z winds should
go southwest under 10kt at APA and DEN, then turn northwest at
around 10KT by 19Z. BJC should be light drainage all night
tonight, then variable through the morning hours. Best bet on
direction at BJC is ENE 5-7kt during the afternoon with the
development of a Longmont Anticyclone.

&&

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

&&

$$

DISCUSSION...AP
AVIATION...Schlatter

NWS BOU Office Area Forecast Discussion