National Weather Service Forecast Discussion

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167
FXUS65 KBOU 282321
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
521 PM MDT Sat Mar 28 2026

.KEY MESSAGES...

- Well above normal temperatures Sunday and Monday afternoons.

- Critical fire weather conditions becoming widespread Monday.

- Cooler by Tuesday with snow in the mountains and a chance of
  precipitation over the plains.

- More upper troughing for next weekend.

&&

.DISCUSSION /Through Saturday/...
Issued at 1224 PM MDT Sat Mar 28 2026

Flat upper ridging will dominate the weather across the forecast
area both today and Sunday with much above normal temperatures.
Weak upper troughing moves across Monday night bringing a cooler
airmass in for Tuesday and Wednesday along with some precipitation.

Currently, surface observations are showing temperatures in the mid
60s to mid 70s across the plains, which is 30 degrees warmer
compared to yesterday at this time. Southwest winds are in place
at 10-25 mph for most areas.

Models have fairly weak zonal flow aloft for the CWA now through
Monday. Moisture will be relegated to the mid and upper levels.
The QG Omega fields are showing very weak to neutral synoptic scale
energy for that period. Cross sections and forecast soundings
point to limited late day high based convection both this
afternoon and Sunday afternoon, mainly producing virga and outflow
wind gusts as high as 40 mph.

With winds progged to increase somewhat on Monday, fire weather
conditions will likely get to critical levels for most of the plains
by afternoon.  This area may eventually require a Red Flag Watch.

The weak upper trough will bring in a decent cold front, upslope low
level flow and increased moisture late Monday night continuing into
Tuesday. The mountains may see a few inches of snow, especially
Tuesday afternoon and evening.

Temperatures may get close to record high values later this
afternoon as well as Sunday and even Monday too. Highs are
expected to be in the lower 80s over the plains all three
afternoons. Tuesday`s highs cool down significantly with highs
mainly in the lower 50s over the plains.

For the later period, Wednesday through Saturday, a weak upper
trough moves across Wednesday, followed by weak ridging.  By Friday
and Saturday, a fairly strong upper trough will affect Colorado,
with the medium range models not the best in agreement concerning
timing.  However, it does look like a cooler and, hopefully, wetter
period may prevail.

&&

.AVIATION /00Z TAFS through 00Z Monday/...
Issued at 516 PM MDT Sat Mar 28 2026

Sporadic virga has been around this aftn with brief gusty outflow
winds. This activity should end by 01z. Naturally winds have had
differing directions due to outflow boundaries but should see
winds become more E/ESE by 01z and then gradually turn more SSW
between 03z and 04z.

On Sun, winds will become more WNW between 16z and 17z and then
NW by 21z. Virga chances Sun aftn look to be lower (10% chance).
Otherwise VFR conditions thru the period.

&&

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

&&

$$

DISCUSSION...66
AVIATION...RPK

NWS BOU Office Area Forecast Discussion