828
FXUS65 KBOU 111908
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
108 PM MDT Sat Apr 11 2026

.KEY MESSAGES...

- Scattered showersand thunderstorms producing gusty winds
  through early evening. Gusty outflow winds (30-45 mph) will be
  common. A couple stronger gusts to 60 mph are possible.

- Warm and dry Sunday and Monday, with breezy/windy conditions
  along with elevated to locally critical fire conditions.

- Weakening disturbance for Tuesday with a chance of mainly light
  showers, then dry weather returns for Wednesday and Thursday.

&&

.DISCUSSION /Through Saturday/...
Issued at 108 PM MDT Sat Apr 11 2026

Water vapor satellite imagery shows a shortwave trough over the
Great Basin at this time. As it tracks northeastward, lift will
spread across the area. Skies have been slow to clear this
morning, but the airmass will destabilize this afternoon. Moisture
will be limited. Even though dew points this morning were in the
30s and 40s, the shallow moisture will mix with the drier air
aloft, causing dew points to fall into the 20s to lower 30s.
SBCAPE climbs to 500 J/kg, which isn`t that impressive. However,
DCAPE reaches1000 J/kg, thus storms will be capable of gusty
outflow winds, with the strongest reaching around 60 mph. Best
chance for storms and strong winds will be mid to late afternoon
along the Front Range and late afternoon to earlyevening over the
eastern plains. Threat for showers/storms ends around sunset as
the airmass stabilizes and the shortwave lifts northeast of the
area.

Southwest flow aloft continues for Sunday and Monday bringing
warm and dryweather. On Sunday, the higher terrain mixes into
stronger southwest winds aloft, leading to gusts around 30 mph.
The threat for gusty winds over the plains will not be as great
due to a forming surface low over northeast Colorado. Weaker
southwest winds to variable are expected under the low. Stronger
winds, which lead to critical fire weather conditions, should
remain over the southern half of the Colorado plains. The Fire
Weather Watch was canceled for most of the northeast plains, but a
strip of zones across our southern area remains under the watch
due to stronger winds, which may still bring gusts up to 30 mph.
Similar weather conditions are expected for Monday, with gusty
southwest winds, strongest over the higher terrain. Moisture
begins to increase from the west as a broad, disorganized upper
level trough approaches the Central Rockies. This will lead to
slightly higher relative humidities over the higher terrain. A few
weak showers will also be possible, beginning in the afternoon.

The chance for showers continues Monday night over the mountains
ahead of the upper level trough. We expect cooler temperatures and
a chance for showers to spread across the area Tuesday. A good
amount uncertainty remains regarding the location and timing of
the shortwave trough(s) embedded in the larger upper level trough.
Precipitation amounts from this system look to be on the light
side.

On Wednesday, weak ridging moves across Colorado. Drier conditions
return and temperatures begin to warm. Flow aloft backs to the
southwest Thursday ahead of the next upper level trough to the
west. Temperatures warm into the 70s across northeast Colorado,
and dry conditions continue. The upper level trough moves across
Colorado sometime Friday and/or Saturday. Ensembles show a very
large spread in how this system evolves, but the general trend is
cooler temperatures (not surprising) and a weaker system with
showers.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1155 AM MDT Sat Apr 11 2026

Winds have been  gusting around 15 to 20 knots for the past
several hours at KAPA and KDEN. We have quickly warmed this
morning to near 70 degrees F at KDEN as of 18z and are starting to
see cumulus clouds across Boulder, Jefferson, and Douglas
counties. A chance for high-based isolated to scattered showers
(30-40%) continues for this afternoon at all three sites. There is
a low chance (10%) for an isolated thunderstorm to occur.
Therefore, we opted to stick with the -SHRA vs.-TSRA. DCAPE values
are expected to be around 700 to 1000 J/kg, but CAPE values
should stay below 400 J/kg this afternoon. To account for any
gusty outflow winds from these showers, there is a TEMPO and
PROB30 for wind gusts of 30 to 40 kts with a low chance (10%) of
these gusts exceeding 40 kts. These would generally occur between
20z and 02z this afternoon and evening.

We eventually turn to drainage winds this evening between 6 and
12 kts. Tomorrow afternoon, winds will stay S to SW, but will
increase with gusts expected to be as strong as 20 to 25 knots
starting around 18z at KAPA and KDEN. Skies will be mainly clear
tomorrow afternoon with only a few mid-level clouds possible.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Sunday afternoon through Sunday evening
for COZ214-216-238-241-246-247.

&&

$$

DISCUSSION...12
AVIATION...MV

NWS BOU Office Area Forecast Discussion