990
FXUS65 KBOU 121117
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
517 AM MDT Sun Apr 12 2026

.KEY MESSAGES...

- Critical fire weather conditions expected today and Monday over
  the southern portions of the forecast area and the plains near
  the Wyoming border.

- Continued above normal warmth Sunday and Monday with a few,
  mainly alpine late day showers.

- The next system will bring cooler temperatures and a decent
  chance of precipitation to the forecast area Tuesday and Tuesday
  evening. Some minor travel impacts possible mountain passes.

&&

.DISCUSSION /Through Saturday/...
Issued at 1155 PM MDT Sat Apr 11 2026

The convection has ended across the CWA late this evening. Drainage
winds are in place across the forecast area. Temperatures were
still in the 50s over the plains at this time and even a tad
warming to decent downsloping winds near the foothills.

Southwesterly flow aloft will dominate our weather now through
Tuesday night.  Jet level wind speeds increase by Sunday night and
continue pretty strong, 90-110 knots, through late Tuesday. By then,
upper level troughing is expected to move across Colorado Tuesday
night through Wednesday morning.  There isn`t much in the way of
synoptic scale energy through Monday. The QG Omega fields have
decent upward motion starting late Monday overnight into Tuesday
with the approaching trough. There is also a cold front for the
CWA Tuesday afternoon and evening.

Moisture is looking scarce for late day Sunday. Will keep the 10-20%
pops going for the mountains late this afternoon and evening. There
will be a little better moisture in the mountains for late day
Monday, so pops will be as high as 40%.  Will increase pops late
Monday overnight and Tuesday with the approaching trough`s incoming
synoptic scale energy and increased moisture. The latest model
runs point to most of the CWA actually getting measurable precipitation
on Tuesday and Tuesday evening, and a few inches of snow in the
mountains.

For temperatures, highs will be well above seasonal normals both
Sunday and Monday. Sunday`s highs will be in the mid to upper 70s
over the plains.  Monday`s highs look a tad cooler with lower to mid
70s for highs there.  Tuesday`s expected cooler airmass keeps highs
in the 60s over the plains and this continues on Wednesday.

For the later days, Thursday through Sunday...there is more
southwesterly flow aloft Thursday into Friday.  This is followed by
a fairly strong upper trough, complete with a decent shot of cold
air, low level upslope flow and the potential for snow over much of
the CWA from later Friday, Friday night on into Saturday.  We`ll
see.

&&

.AVIATION /12Z TAFS through 12Z Monday/...
Issued at 517 AM MDT Sun Apr 12 2026

VFR conditions will persist through the period. No showers or
thunderstorms are forecast, although we will see some high based
cumulus. The threat of any variable gusty outflow winds from those
22Z-02Z would be less than 10%.

Winds are starting from the S-SW, and should persist through at
least 18Z with just a slight SW-WSW shift expected. After 18Z,
we`ll see stronger mixing but there remains some uncertainty in
direction without much if any downward forcing. We do think the
mixing will be sufficient for a few SW-W gusts to 20-22 kts after
21Z (slightly earlier at KAPA). However, there`s a 30% chance
winds stay lighter and even retain a more S-SE component in the
afternoon. Winds will eventually return to more S-SW by 03Z-05Z
Monday and hold through early Monday morning.

&&

.FIRE WEATHER...
Issued at 1137 PM MDT Sat Apr 11 2026

We went with a Red Flag Warning Sunday afternoon into early
evening for the southern CWA Zones and Zone 238 due to the low
humidity levels and wind gusts to 30 mph. Fuels remain extremely
dry in these areas. We also went with the Fire Weather Watch over
similar areas for Monday afternoon and early evening, due to the
same conditions.

There looks to be elevated to critical fire weather conditons
Thursday afternoon as well.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon today to 8 PM MDT this evening for
COZ214-216-238-241-246-247-249.

Fire Weather Watch from Monday morning through Monday evening
for COZ214-216-238-241-242-246-247-249.

&&

$$

DISCUSSION...66
AVIATION...20
FIRE WEATHER...66

NWS BOU Office Area Forecast Discussion