National Weather Service Forecast Discussion

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005
FXUS65 KBOU 091133
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
533 AM MDT Mon Mar 9 2026

.KEY MESSAGES...

- Much above normal temperatures today and 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 for
  the second half of the week.

&&

.DISCUSSION /Through Sunday/...
Issued at 1122 PM MDT Sun Mar 8 2026

A dry period, with above normal temperatures, is expected for
the CWA much of this coming week. These parameters will produce
elevated fire weather conditions over the plains early in the
week, with critical fire weather conditions by Thursday and Friday
as wind speeds are forecast to increase.

Models indicate weak to moderate west-southwesterly flow aloft for
the forecast area tonight through Monday.  Weak upper troughing
pushes across the CWA Tuesday with very little synoptic scale energy
associated with it. By Tuesday night, strong northwesterly flow
aloft moves into the CWA behind the trough and this continues into
Thursday.

Concerning moisture, there is a bit expected with and behind the
weak trough, mainly on Tuesday afternoon into Tuesday night. There
may be just enough on Tuesday evening for minor pops over the
mountains and northern border plains. Otherwise, there is some mid
and upper level moisture through the week, but nothing significant.

For temperatures, thickness grids show Monday`s highs about 1-3 C
warmer then today`s highs, so will go with lower and mid 70s for
the plains. Tuesday`s readings cool down a slight bit, especially
over the northeast corner where models are still showing weak cold
front to move in. Models continue showing a more substantial cool
down Tuesday night with a cold front associated with the weak
passing trough moves across the area. Even with the cool down,
Wedenesday`s highs over the plains will be a tad above seasonal
normals with mid and upper 50s for the urban corridor. Thursday`s
highs are progged to warm up substantially.

For the later days, models continue to show northwesterly flow aloft
over the CWA Friday into early next week.  Models have a strong jet
maximum moving in during the later half of the weekend along with
pretty deep moisture. There is a cold front with upslope for the
plains as well by later Sunday into Monday.  Temperatures are well
above normals Friday and Saturday, but cool down to just above
normals Sunday and Monday.

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 532 AM MDT Mon Mar 9 2026

VFR will persist with only SCT-BKN high clouds. South/southwest
winds are expected to hold at KDEN and KAPA through at least 18Z,
although a couple periods of lighter S/SE winds are possible with
mountain wave along the Front Range this morning. The winds are
expected to start turning more SW-W-WNW with peak heating and
mixing, but with some cirrus clouds that full mixing and westerly
shift could be delayed til about 20-21Z. There`s even a slight
chance (20-25%) that the west winds never do mix and we end up
with VRB or light east winds at times 20Z-24Z. Winds will then
turn back south/southwest 01Z-05Z and hold through 18Z Tuesday.
A backdoor cold front does approach Tuesday morning so something
to keep an eye on for a sneaky wind shift.

KBJC will be a few hours earlier (17Z-20Z) with the westerly wind
increase, with gusts to 20-27 kts expected off/on through 04Z.
Then, winds should settle again to a lighter southwest component.

&&

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

&&

$$

DISCUSSION...66
AVIATION...20

NWS BOU Office Area Forecast Discussion