766 
FXUS65 KBOU 070839
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
239 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 /06Z TAFS through 06Z Tuesday/...
Issued at 1112 PM MDT Sun Sep 6 2026

An outflow boundary from earlier tstms near the foothills has
moved across with a wind shift to the W/WSW.  These winds should
become more SSW/S by 07z at APA/DIA with WNW winds at BJC.

On Mon, winds will be light and variable by 13z and then trend to
more easterly at BJC and DIA by 17z. At APA, winds will be from
the NW by 19z. There will be a chc of showers/tstms by 22z which
will linger thru 02z Mon evening.  For now have kept a prob30
between 22z and 02z with brief gusty winds up to 35 mph possible.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...RPK