831
FXUS65 KBOU 310515
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1115 PM MDT Sun Aug 30 2026

.KEY MESSAGES...

- Better precipitation chances on Monday, with another round of
  afternoon/evening showers and storms, a few may become severe.

- Warmer and drier conditions expected from Tuesday onward.


&&

.DISCUSSION /Through Sunday/...
Issued at 124 PM MDT Sun Aug 30 2026

Current radar shows storms are making their way off the northern
Front Range early this afternoon, with another round moving across
the Continental Divide. The primary hazard with today`s showers and
storms will, once again, be strong outflow winds. So far, storms
have been producing a few tenths of rainfall and wind gusts between
40 to 50 mph. Storms have been moving between 30-40 kts, which will
help keep flash flooding concerns limited, but if we do see any back-
building, there is enough moisture in place to see some heavy
downpours, mainly across the higher elevations. While today`s
instability is expected to be slightly increased over Saturday, it
remains fairly weak, with only a few hundred to roughly 500 J/kg
of MLCAPE observed on the SPC mesoanalysis. CAMs continue to be in
decent agreement about high-based storms/showers continuing their
trek eastward across the plains through the afternoon and
evening. These will be capable of producing strong outflow winds,
with at least a few severe wind gusts possible. Current
temperature readings show roughly a ten degree difference from
this time yesterday, with today`s afternoon highs forecast to run
a few degrees cooler than yesterday.

Southwesterly flow aloft will continue to usher monsoonal moisture
into Colorado on Monday. Given the increased moisture, proximity to
the right entrance of a 500 mb jet, and the aid of lift from an
approaching shortwave sometime in the afternoon/evening, this will
be our best chance for precipitation across the forecast area
with this wave of monsoonal moisture. CAMs continue to show a
cluster of storms move through the Four Corners Monday morning,
pushing northeast across Colorado through the day. We could see a
few stronger to severe storms in the afternoon, with the CAMs
honing in on the better instability being along and east of the
Palmer Divide (as high as ~1200 J/kg of MLCAPE). Given the better
moisture, we will have a better chance for some localized heavier
rainfall amounts, but with the mean flow aloft roughly moving
35-40 kts, this should help limit flash flood potential.
Additionally, with DCAPE ranging from 1200-1500 J/kg across the
plains, generally east of the urban corridor, the primary threat
will be with gusty outflows once again, but with increasing 0-6 km
bulk shear, we may see some marginally severe hail with some of
the stronger storms. Depending on the timing of the shortwave, we
could see showers/storms linger late into the night. Near normal
temperatures are expected across the forecast area.

Southwesterly flow aloft will remain in place through the week as
the upper-level ridge persists over the eastern US. Monsoonal
moisture is expected to continue flowing into the region, but
amounts are expected to diminish for a few days midweek, as the
higher amounts should stay to our southeast. Things in the Pacific
look to become active over this period, from a parade of storms
moving towards Hawaii, to a fairly strong closed low dropping south
along the West Coast. Depending on how these features interact, we
could see some more active weather return by late in the week, but
for now, the forecast calls for slightly less convection each
afternoon after Monday, with near normal temperatures on Tuesday,
gradually warming through the end of the work-week.

&&

.AVIATION /06Z TAFS through 06Z Tuesday/...
Issued at 1111 PM MDT Sun Aug 30 2026

Sct hi based showers continue to move across the area late this
evening with some microburst activity. Expect this activity will
end around 07z. A few brief gusts from 35 to 45 mph will be
possible. Winds will be mainly from the south overnight except at
BJC which will have a westerly direction.  By 15z Mon, winds will
become light and variable and then gradually shift to ENE/E
direction by early aftn.

At this time it appears most shower/tstm activity will hold off
until after 21z and will continue into early Mon evening.  Once
again will see gusty and erractic winds with the activity.

&&

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

&&

$$

DISCUSSION...9
AVIATION...RPK

NWS BOU Office Area Forecast Discussion