National Weather Service Forecast Discussion

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561
FXUS65 KBOU 302346
AFDBOU

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

.KEY MESSAGES...

- Scattered showers and storms capable of producing strong to
  severe wind gusts are expected to continue through the evening.

- 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 /00Z TAFS through 00Z Tuesday/...
Issued at 545 PM MDT Sun Aug 30 2026

Radar as of 2345z is rather quiet across the Denver metro after
an afternoon of showers, thunderstorms, and gusty winds at all
three sites. CAMs continue to suggest the possibility of
additional high-based showers and thunderstorms either moving off
the Palmer Divide or the higher terrain to the west this evening
through 5z. These could bring gusty outflow winds in excess of 35
kts and briefly lowering ceilings. Behind the convection, winds
will shift to drainage through Monday morning.

Winds should turn clockwise to north-northeast or even east by
early tomorrow afternoon. Have continued to refine the timing of
showers/thunderstorms for tomorrow afternoon and evening based on
the latest CAMs. A TEMPO and VCTS starts at 21z (20z for KAPA) for
similar threats to today- gusty outflow winds in excess of 35
kts and briefly lowering ceilings. Ceilings could briefly drop to
around 7000 feet AGL given more mid-level moisture than today is
expected to be present. A PROB30 is in place for tomorrow evening
with additional rounds of SHRA/TSRA possible. Timing of the
SHRA/TSRA will continue to be refined in future updates.


&&

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

&&

$$

DISCUSSION...9
AVIATION...MV

NWS BOU Office Area Forecast Discussion