408
FXUS65 KBOU 232357
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
557 PM MDT Sun Aug 23 2026

.KEY MESSAGES...

- Scattered afternoon and evening showers and storms through
  Thursday. A risk of a couple severe storms each day especially
  Tuesday and Wednesday.

- Slightly cooler with near normal temperatures for Tuesday and
  Wednesday.

- Gradual drying and hotter temperatures by the end of the week
  and through next weekend.

&&

.DISCUSSION /Through Sunday/...
Issued at 1245 PM MDT Sun Aug 23 2026

The flow aloft will be mainly WNW this aftn thru tonight with PW
values 100 to 150 percent above normal.  Don`t really see anything
aloft to enhance tstm development, so will see another round of sct
showers and storms across the CWA.  Overall, expect mostly outflow
dominant storms with gusty winds and possibly some marginal large
hail over the plains. DCAPE values are mainly at or below 1000
j/kg but a few storms may still produce brief wind gusts from 55
to 65 mph.

On Mon, the flow aloft will remain WNW with some decrease in
moisture as PW values drop to 100 to 125 percent above normal. As
a result, may see less activity Mon aftn and evening. DCAPE
values are fcst to rise to 1000 to 1500 j/kg, so there will be
some potential for gusty outflow winds from the activity. Highs
will be in the upper 80`s to mid 90`s.

For Tue, the flow aloft will be slightly stronger from the WNW as a
weak cool front moves into nern CO.  As a result, will see
temperatures drop back to more seasonal levels with an increase in
low level moisture across nern CO.  Will see a better chc of showers
and tstms across the higher terrain by aftn.  Across the plains,
initial tstm development may focus over the Cheyenne Ridge and
Palmer Divide by mid to late aftn and then track across the plains
by Tue evening.  MLCAPE will range from 1000-1500 j/kg with
favorable shear. Thus would expect a few svr storms across the
plains.

On Wed, the flow aloft will become more NWLY.  MLCAPE will range
from 1000-1500 j/kg, across nern CO, with the higher values over the
I-25 Corridor.  With favorable shear, should see a few svr storms by
mid to aftn along portions of the I-25 Corridor which will move
across the plains during the early evening hours.  Over the higher
terrain will see sct showers and storms.  Highs on Wed, will stay in
the 80`s across the plains.

Looking ahead to Thu and Fri, the upper level ridge will extend from
the srn Rockies into the swrn US.  As a result, this will leave the
area in WNW flow on Thu becoming more westerly by Fri.  Current data
shows some decrease in moisture both days, however, still expect sct
showers and storms over the higher terrain with widely sct activity
across the plains.   Highs will be near seasonal levels on Thu and
then back to above normal by Fri.

By next weekend, the flow aloft will become more WSW.  Will still
see some influx of monsoon moisture with widely sct showers and
tstms possible both days.  Highs will remain above normal.

&&

.AVIATION /00Z TAFS through 00Z Tuesday/...
Issued at 556 PM MDT Sun Aug 23 2026

While the main storm/thunder threat has started pushing eastward out
of the area, gusty winds from microbursts and outflows are expected
to prevail for the next hour or so. There`s a lot of uncertainty as
to which outflows will dominate and whether or not more showers and
isolated storms will develop as the evening wears on. We`ve extended
the TEMPO to 01Z to account for any showers or other outflows that
form in the near future off of existing convection. There could be
gusty winds and scattered showers through 03Z, though confidence is
lower on timing and location. Once any lingering showers/gusts move
out of the area, winds should start turning towards drainage and
skies should clear up. By around 15Z, winds will turn north and then
northeast, following the typical diurnal cycle. Though the CAMs have
backed off on tomorrow`s convection from what we saw this morning,
we still expect to see another round of storms & gusty outflows
starting around 22Z and hanging in the area through roughly 01Z,
after which winds should start turning east and then south back
towards drainage overnight.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...AGS

NWS BOU Office Area Forecast Discussion