770
FXUS65 KBOU 071116
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
516 AM MDT Mon Sep 7 2026

.KEY MESSAGES...

- Better chance for showers and thunderstorms this afternoon with
  locally heavy rain in a few areas across the plains.

- Temperatures will remain very warm, with only slight cool down
  Tuesday and Wednesday.

- Chance of afternoon thunderstorms mainly Palmer Divide and east
  central plains on Tuesday,

- Warmer and drier for Thursday and Friday.

- Some potential for a brief cooldown next weekend.

&&

.DISCUSSION /Through Sunday/...
Issued at 233 AM MDT Mon Sep 7 2026

A upper level trough will move across the nrn Rockies today thru
tonight with SW flow aloft across the area. Monsoon moisture will
be embedded in the flow with PW values 150 to 175 percent above
normal. MLCAPE will be around 1000 j/kg from the Palmer Divide
across the far ern plains this aftn with lower values further
west. Overall, will see a good chance of showers/tstms this aftn
thru the evening hours, especially across the plains. There is
enough shear for an isold svr storm or two where the highest
MLCAPE will exist this aftn. In addition, with decent PW`s some
locally heavy rainfall will be possible as well. Highs this aftn
will be in the upper 80`s to mid 90`s across the plains.

On Tue, the flow aloft will become more westerly as a wek cool front
moves across the plains.  There will still be some monsoon moisture
embedded in the flow, however, PW values will decrease, especially
across the nrn half of the area.  Best chc for showers/tstms will be
over the Palmer Divide and sern areas of the plains.  MLCAPE is fcst
to be in the 500-800 j/kg range, however, shear will be better so
can`t rule out an isold svr storm over the Palmer Divide.  Highs
across the plains will be in the 85 to 90 degree range.

For Wed, the flow aloft will become more WNW as a surge of cooler
air moves across late Tue night into Wed morning.  This will lead
mainly dry conditions with highs across nern CO in the upper 70`s to
mid 80`s.

Looking ahead to Thu and Fri, the flow aloft will be mainly zonal
with minimal moisture embedded in the flow.  As a result, expect
mainly dry conditions both days with warmer temperatures as readings
over nern CO rise back into the upper 80`s to lower 90s.

For next weekend, the flow aloft will remain zonal on Sat as another
weak front moves across.  As a result, highs will drop back into the
80`s across the plains.  Meanwhile, will leave in a slight chc for
aftn tstms across the area.  On Sun, the flow aloft will become more
SW as an upper level trough moves into the nrn Rockies.  The GFS is
faster with moving a cold front across the area during the day while
the ECMWF is slower.  With SW flow aloft and upper level trough
still to the NW of the area, ECMWF probably has a better handle on
timing of front.  Thus may see highs reach the upper 80`s to lower
90`s over nern CO on Sun before it reaches the area Sun night.

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 512 AM MDT Mon Sep 7 2026

Winds will become light and variable by 14z and then trend to
more easterly at BJC and DIA by 17z. At APA, winds will be from
the SE by 17z and then switch to the NW by 21z. There will be a
chc of showers/tstms by 22z which will linger thru 02z this evening.
Have kept a prob30 between 22z and 02z for -tsra with brief gusty
winds up to 35 mph possible.

By 02z, shower/tstm activity should end with winds becoming SE/S
and then S/SSW by 06z.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...RPK