National Weather Service Forecast Discussion

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007
FXUS65 KBOU 091956
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
156 PM MDT Mon Mar 9 2026

.KEY MESSAGES...

- Much above normal temperatures again Tuesday, with elevated
  fire weather conditions.

- Slight chance for precipitation for the mountains and northern
  plains Tuesday evening.

- Strong winds and critical fire weather concerns possible
  Thursday through Saturday.

&&

.DISCUSSION /Through Monday/...
Issued at 156 PM MDT Mon Mar 9 2026

Strong zonal flow will continue to stream across the northern
part of the country tonight, with weak westerly flow aloft over
Colorado. Overnight lows will run above normal due to the warm
airmass in place. The flow aloft will buckle Tuesday as a weak
shortwave trough tracks across the Northern Rockies. Flow aloft
turns to the northwest late in the day. Warm air will stay in
place Tuesday with highs reaching the 70s across northeast
Colorado. A cold front associated with the system passing to our
north sneaks into northeast Colorado during the morning hours and
stalls. Models then show the front will sweep south across
Colorado Tuesday evening and night. Can`t rule out the front
pushing farther south during the morning/early afternoon than the
models show. The northern mountains is expected to pick up a
little snow (up to 3 inches) with this system Tuesday night. Dry
conditions are expected across the rest of the area with a
temporary cool down for Wednesday. Temperatures cool to near
normal Wednesday with temperatures in the 50s.

Upper level ridging intensifies over California and off the
California coast Thursday and Friday. This will cause flow aloft
over Colorado to become west-northwest and increase. Temperatures
warm up over the region with highs returning to the 70s over
northeast Colorado. Dry conditions with low relative humidities
are expected to prevail Thursday through Saturday. Due to the
increasing flow aloft, windy conditions are expected. We are
looking at two periods of concern, with very windy (critical fire
weather) days possible. The first one is Thursday when a shortwave
trough and surface low pass north of Colorado. There`s some
uncertainty on just how windy and how far south the stronger winds
will spread, but this weather pattern tends to favor windy to
very windy conditions across northeast Colorado. A mountain wave
is could form Thursday with 80 mph possible for the foothills. A
similar set up takes place Saturday as well. Saturday`s shortwave
trough and surface low are on track to be stronger. We`ll see a
cold front race south across the area late Saturday or early
Sunday ending the fire weather concerns. This could bring light
rain/snow to the area Sunday. Northwest flow aloft prevails for
Sunday and Monday. This could produce snow in the mountains, if
enough moisture is available. Temperatures will not be as warm for
Sunday and Monday, but look to be at or slightly above normal.

&&

.AVIATION /18Z TAFS through 18Z Tuesday/...
Issued at 1151 AM MDT Mon Mar 9 2026

VFR conditions to prevail through the TAF period. Winds have
become light and variable across the Denver TAF sites late this
morning. The latest KFTG VAD profiler shows westerly winds are
just off the deck, and with further mixing expected through the
afternoon, these westerly winds will likely make their way to the
surface. The latest ACARS sounding shows a slight inversion around
750 mb (3,500 - 4,000` AGL) with 20kt winds just above it. With
just a few more degrees of surface heating we should be able to
mix that out, bringing the stronger gusts down. Expect gusts
between 15-25 kts once this occurs, starting by 20-21Z, and
settling down around sunset this evening.

Drainage winds are likely to set in across the TAF sites between
3-6Z tonight. Early tomorrow morning (11-12Z) winds are expected
to make a more southerly turn before turning back WSW by 16Z with
potential for gusty west winds to channel their way into the TAF
sites shortly thereafter (17-18Z).

&&

.FIRE WEATHER...
Issued at 156 PM MDT Mon Mar 9 2026

It will be another warm dry day Tuesday over northeast Colorado
with relative humidities in the teens. Elevated to locally
critical fire weather conditions are expected during the afternoon
hours, mainly towards the Wyoming border where wind gusts to 35
mph will be possible. A cold front brings a wind shift Tuesday
evening and cooler temperatures for Wednesday. Locally elevated to
critical fire weather conditions will be possible over far north
and northeast Colorado where breezy conditions are expected.

Very warm and dry conditions return to the area Thursday through
Saturday. A surface low passing north Colorado will tighten the
pressure gradient, likely bringing windy conditions to the area
Thursday. Strong winds are also a possibility for the foothills if
a mountain wave forms. Windy conditions will continue to be
possible Friday and Saturday under an increasing northwest flow
aloft.

&&

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

&&

$$

DISCUSSION...12
AVIATION...9
FIRE WEATHER...12

NWS BOU Office Area Forecast Discussion