National Weather Service Forecast Discussion

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934
FXUS65 KBOU 020514
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1114 PM MDT Tue Sep 1 2026

.KEY MESSAGES...

- Warmer and drier conditions expected through Friday.

- Only a slight chance for showers and thunderstorms today and
  tomorrow, with the greatest chances in the high country.

- Return of better moisture by the weekend with an increasing
  chance for showers and thunderstorms across the high country.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1245 PM MDT Tue Sep 1 2026

GOES-19 satellite imagery shows some cumulus clouds mainly in our
far western high country. Radar shows light rain lingering in far
eastern parts of our area as the shortwave continues to depart our
area. SW flow aloft is still in place today, but PWATs are much
closer to average than the last couple of days. Isolated to perhaps
scattered high-based showers or storms are possible today across
most of the area. The far eastern plains locations would have the
highest risk for a severe storm producing gusty outflow winds (given
DCAPE approaching 1000 J/kg) and small hail. Although the risk is
rather low, it is non-zero. MLCAPE values should reach around
1000 J/kg and bulk shear will reach around 30 kts, only for the
eastern plains. High temperatures today will be in the mid 80s for
the plains.

There will be another chance for an isolated high-based shower or
storm tomorrow, but these are currently expected to stay mainly
confined to the high country. PoPs generally drop to below 10% for
Thursday. Otherwise, temperatures on the plains will warm into the
upper 80s to low 90s on Wednesday and Thursday.

By Friday and Saturday, high pressure shifts closer to us allowing
temperatures to creep up into the low to mid 90s for the plains.
Monsoonal moisture starts to make its return to the state on Friday
into the weekend aided by moisture associated with what will likely
be Hurricane Marie in the eastern Pacific. PWATs look to return to
well above average. As of now, rain chances appear to peak on
Sunday and Monday for our area with the greatest chances for our
high country. Questions remain about how widespread rainfall will
be east of the Continental Divide this weekend. Ensemble guidance
keeps temperatures for the plains in the upper 80s and low 90s
through at least Tuesday of next week.

&&

.AVIATION /06Z TAFS through 06Z Thursday/...
Issued at 1109 PM MDT Tue Sep 1 2026

Winds will gradually go drainage by 07z and continue overnight. On
Wed, winds will become more SE by 19z. Latest data suggest there
will be sct high based -shra by 22z with a 10 percent chc of
-tsra. DCAPE values are around 1000 j/kg so expect gusty and
 erractic outflow winds thru early Wed evening. Winds may shift to
 more northerly by 00z and then to easterly by 04z.


&&

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

&&

$$

DISCUSSION...MV
AVIATION...RPK

NWS BOU Office Area Forecast Discussion