150
FXUS65 KBOU 251130
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
530 AM MDT Wed Mar 25 2026

.KEY MESSAGES...

- Record heat for Wednesday. We may approach or tie monthly
  record highs set just last week.

- Elevated to locally critical fire weather conditions, mainly on
  Wednesday.

- A cold front arrives sometime Thursday, with the coolest day on
  Friday.

- Temperatures warm well above normal again for the weekend into
  early next week.

&&

.UPDATE...
Issued at 423 AM MDT Wed Mar 25 2026

Consistent downslope flow has kept calm winds at bay and is
sustaining exceptionally warm conditions through the current hour
across the Front Range urban corridor, with temperatures hovering
between 65-74 degrees along the Hwy 93/US-36 corridors as of 4:30AM.
Have adjusted temperatures upward for today, including a slight
upward nudge in daytime highs given the warm start and potential for
relatively late (~3-4pm) development of increased mid-level cloud
cover. If we`re able to warm up fast enough before this occurs, all-
time March records will be within reach for some locations.

The latest suite of guidance has put a pause on the acceleration
of Thursday`s cold front or even slowed it, thus providing a
greater opportunity for temperatures to warm more readily across
the southern half of our forecast area. Thus, have also modestly
increased high temperatures for Thursday for the I-70 and I-25
corridors in particular.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1112 PM MDT Tue Mar 24 2026

Upper level high centered along the US/Mexico border will
dominate the weather pattern Wednesday with record highs expected
for most locations. Skies have cleared some over the past few
hours, but the next batch of high clouds over the Great Basin will
move over the area towards sunrise Wednesday morning. These
clouds move off around midday, then during the afternoon hours we
see an increase in mid level clouds. By late afternoon, soundings
show we could even see some virga with gusty outflow winds to 40
mph.

The ridge is knocked down Thursday by a shortwave trough. At the
surface a cold front pushes southwest across eastern Colorado
during the late morning and afternoon. Ahead of it, temperatures
stay mild, but winds turn northerly Thursday morning as surface
pressure lowers over southeast Colorado and Kansas. With this
setup, would not be surprised the front arrive earlier, possibly
several hours early than the models show. Thus, the temperature
forecast is highly uncertain and depends when the cold front
arrives. The front will be strong enough that temperatures are
expected to fall through the afternoon hours. Low and mid level
moisture increases behind the front, and models show deep enough
upslope flow for light rain/snow showers along the Front Range
Thursday evening. Precipitation amounts will be light and are
expected to be less than a tenth inch.

On Friday, we lose the mid level clouds, but hang onto the low
level moisture/clouds through most or perhaps all day. The cooler
air and cloud cover will keep temperatures cool with highs in the
50s across northeast Colorado.

For the weekend, temperatures quickly warmup with a flat upper
level ridging rebuilding over the region. The main upper level
high will be centered over Texas with low aloft becoming more
southwesterly Sunday and into next week. For Sunday and Monday,
highs are expected to reach the upper 70s to lower 80s, which will
be close to record highs. With the help of a weak upper level
trough, moisture increases over the region Sunday and into early
next week. The mountains will see rain/snow showers and times with
a slight chance for light rain east of the mountains.

&&

.AVIATION /12Z TAFS through 12Z Thursday/...
Issued at 524 AM MDT Wed Mar 25 2026

VFR conditions will prevail for all terminals through the TAF
period. SW drainage flow is expected to persist at the terminals
through mid-morning, and is subsequently favored to transition to
westerly flow 16-18Z as daytime mixing increases. Although surface
troughing to the northeast would tend to favor easterly flow,
suspect it may be too far removed most of the day for this to
materialize, and downslope flow has also been quite consistent
during the early morning hours of Wed. The greater uncertainty
with the wind directions arrived mid-afternoon, with increasing
mid-level moisture and potential for weak high-based
convection/virga, mainly after 23Z. The bulk of this activity is
expected to remain closer to the Palmer Divide, but would drive
increased potential for a period of southeasterly outflow,
primarily for KDEN/KAPA. Although precip is unlikely with any of
this convection, it would be capably of gusty convective outflows,
and thus PROB30 groups have been maintained for those two
terminals.

As the weak mid-level convection moves east, winds will return to
southerly drainage relatively quickly Wed evening.

&&

.FIRE WEATHER...
Issued at 1112 PM MDT Tue Mar 24 2026

Record warmth is once again expected Wednesday with relative
humidity levels dropping to around 10% across the plains. In the
foothills and mountains valleys, relative humidities bottom out at
13-20 percent. The flow aloft is not very strong, so even during
peak heating we think most wind gusts will stay under 25 mph.
However, the winds are a little stronger to the north so gusts
closer to 30 mph can be expected from Jackson County into the far
northern foothills near the Wyoming border. Humidity levels there,
will be more marginal. Therefore, the overlap of having both RH
and wind gust criteria met in the same location is rather limited
and not widespread enough for any Red Flag Warnings.

On Thursday, elevated to locally critical conditions, will be
possible in the mountain valleys with west winds gusting to 20 to
30 mph. Over the plains, a cold front pushes through during the
late morning and early afternoon. The morning may be warm and dry,
but falling temperatures and increasing relative humidities are
expected during the afternoon.

&&

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

&&

$$

UPDATE...BRQ
DISCUSSION...12
AVIATION...BRQ
FIRE WEATHER...12

NWS BOU Office Area Forecast Discussion