338
FXUS65 KBOU 101906
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
106 PM MDT Tue Mar 10 2026

.KEY MESSAGES...

- Gusty north winds up to 50 mph over the plains this evening
  behind a cold front.

- Scattered snow showers for the mountains and rain/snow showers
  for the northern plains tonight.

- Cooler on Wednesday with elevated to critical fire danger at
  lower elevations near the Wyoming border.

- Strong winds and critical fire weather concerns likely (>70%
  chance) Thursday through Saturday.

&&

.DISCUSSION /Through Tuesday/...
Issued at 106 PM MDT Tue Mar 10 2026

Shallow layer of cold air has surged south and west this morning.
Making it as far west as the lower foothills (~7000 feet MSL).
Temperatures fell into the upper 30s to lower 40s across the Front
Range and into the 20s over the far northeast plains. Model
guidance did poor job capturing this, with model temperature 2-3
hour forecast off by 20 degrees in some locations. Not surprising,
there`s low confidence in the temperature forecast for the rest
of today. All the models show west winds mixing down and the
temperature shooting up into the upper 60s to lower 70s across the
Front Range. Not confident in this, though temperatures are
starting to recover. Lowered highs for today, especially across
the northeast plains where the colder air is likely to stay in
place. As far as the Red Flag Warning goes, plan on canceling it
soon unless we see stronger west winds start to spread down the
lower foothills and onto the plains.

Upper level trough centered near Yellowstone National Park will
continue to track southeastward. A cold front associated with this
system races south across the area this evening bringing gusty
north winds of 40 to 50 mph. Scattered showers are expected to
form behind it, most numerous over far northern Colorado where the
better lift will reside. For the northern mountains, up to 3
inches of snow will be possible. This system shifts east of the
region by Wednesday morning with only a few lingering flurries
possible in the mountains. It will be cooler Wednesday behind this
system with highs in the 50s over northeast Colorado.

Thursday through Saturday, west-northwest flow aloft will prevail
through this time range. Warm and dry conditions will occur under
this pattern. Highs reach the upper 60s to mid 70s, warmest on
Saturday. Relative humidities fall into the teens each afternoon.
Saturday will also be the driest day with lower teen and upper
single digit relative humidities expected. Flow aloft increases,
and is somewhat strong with winds aloft reaching 100 knots. The
main jet stays north of the region, but flow aloft is strong
enough to bring windy to very windy conditions at times. Strong
agreement among the models that a mountain forms Thursday and
Thursday night over the foothills. It`s unclear how far east these
strong winds spread. We`ve issued a High Wind Watch for the
foothills, and also the nearby lower elevations (Zones 38 and 39),
mainly for the area near the base of the foothills. Most models
keep the stronger winds in the foothills, but this event is just
reaching the HiRes model forecast period. Wouldn`t be surprised to
see some stronger winds right at the base of the foothills. For
the rest of the area, very windy conditions are expected over far
northern Colorado (near the Nebraska/Wyoming borders). Channels of
gustier winds are also expected across the plains. Decided to
issue a Fire Weather Watch for the lower elevations mainly north
of I-70 Thursday.

Gusty winds will be possible Friday as well with Fire Weather
being a concern again. Appears Saturday will be the windiest day
ahead of an approaching upper level trough. Widespread windy
conditions are expected to develop, with high/strong winds a
possibility. This could result in a higher end Red Flag day.

Cold front and upper level trough track across the area Saturday
night. This will bring a chance for rain/snow to the lower
elevations with snow for the mountains. Northwest flow aloft will
prevail Sunday bringing cooler temperatures to the area. Snow may
continue in the mountains Sunday if enough moisture is present.
The mountain snow could even linger into Monday before an upper
level ridge takes hold of the weather. A warming trend begins
Monday with highs climbing into the 50s over northeast Colorado.
For Tuesday, the region sees the full effects of the upper level
ridge with temperatures climbing into the 70s across northeast
Colorado.

&&

.AVIATION /18Z TAFS through 18Z Wednesday/...
Issued at 1238 PM MDT Tue Mar 10 2026

UPDATE: Confidence is increasing that the boundary will make it
far enough south to reach KAPA. It`s looking increasingly likely
the stronger westerly winds will not mix down, and will be making
the same changes to the KAPA TAF that are discussed below for the
other TAF sites.

PREVIOUS DISCUSSION: Low confidence in this afternoon`s forecast.
This morning`s cold front has proven to pack more of a punch than
guidance had suggested. This leaves much uncertainty in how the
rest of today will play out. The previous forecast called for
gusty west winds mixing down with forecast temperatures in the
upper 60s to low 70s. The cold front has kept a significant
temperature gradient in place across our TAF sites (currently 47F
at KDEN, 64F at KAPA), with NE winds continuing to spill across
KDEN/KBJC, and gusty SW winds remaining at KAPA. Due to this, it`s
looking like there is far greater potential in the gusty west
winds mixing down at KAPA, and less likely we warm up enough at
KDEN/KBJC (but not impossible). This forecast package comes with
some significant changes for today. Guidance has been very slow to
catch on to the latest atmospheric changes, and has done little
in terms of guiding this morning. Therefore, we have decided that
we will be more likely to hang onto the NE winds through the
afternoon, with some potential that enough surface heating occurs
to allow the stronger westerlies to mix down sometime after the
20Z time frame. Have moved the westerlies into a TEMPO and kept
the N/NE winds in the prevailing, but this is still subject to
change.

A more potent cold front is expected to slide south across the
TAF sites between 2-3Z tonight. With this front, a northerly shift
is expected with gusts between 30-40 kts and some lower clouds
(10-15% chance we see CIG as low as BKN060), but chances for any
precip are too low to include in the TAF. If anything were to
fall, it would be very light rain. There are some inconsistencies
with guidance outputs for after the front. CAMs are showing winds
diminishing by 5Z and turning east to southeast, while MOS
guidance holds onto the N winds potentially through the afternoon
tomorrow. With the CAMs struggling so much with today`s
conditions, have leaned more on the MOS for tomorrow`s forecast,
but it should be noted that the CAMs do show a second northerly
push by 12Z that would align with the MOS. Uncertainties linger
into tomorrow afternoon, but the current TAF looks to be a solid
starting point.

&&

.FIRE WEATHER...
Issued at 106 PM MDT Tue Mar 10 2026

A weak cold front has surged southwest across the urban corridor
and eastern plains, reaching about 7000 feet MSL in the northern
foothills. It appears the strong west to southwest winds just
above the cooler air will not surface, therefore plan on canceling
the Red Flag Warning for today. A cold front will bring a strong
wind shift to the north this evening with gusts of 40 to 50 mph as
the front pushes through. In addition to cooler temperatures and
increased moisture, scattered showers are expected to form behind
the front, most numerous over far northern Colorado. Cooler
conditions will prevail Wednesday behind the front, but breezy
north to northwest winds are expected over the northeast plains.

Thursday through Saturday is looking like a windy to very windy
period under a dry and mild west-northwest flow aloft. Very windy
conditions will be possible in and near the foothills as a
mountain wave is expected to form. These strong winds are expected
to be confined in/near the foothills, but windy conditions will
be possible across the plains north of I-70. Windy conditions
continue Friday and Saturday with strong winds a possibility again
on Saturday.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
High Wind Watch from late Wednesday night through late Thursday
night for COZ035-036.

High Wind Watch from Thursday morning through late Thursday
night for COZ038-039.

Fire Weather Watch from Thursday morning through late Thursday
night for COZ238-239.

Fire Weather Watch from Thursday morning through Thursday
evening for COZ240-242>245-248>251.

&&

$$

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

NWS BOU Office Area Forecast Discussion