National Weather Service Forecast Discussion

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565
FXUS65 KBOU 240927
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
327 AM MDT Fri Jul 24 2026

.KEY MESSAGES...

- Storm coverage decreasing today with highest coverage over the
  higher terrain.

- Warmer today with very hot temperatures this weekend, across
  the plains, with a few record highs possble.

- Heat Advisory issued for the I-25 Corridor both Saturday and
  Sunday.

- Monsoon moisture will increase on Sunday and continue over the
  the area early next week. There will be an increasing chance of
  thunderstorms over the higher terrain by Sunday and then over
  most of the area for Monday and Tuesday.

&&

.DISCUSSION /Through Thursday/...
Issued at 319 AM MDT Fri Jul 24 2026

For today, there will be a decrease in monsoon moisture across the
area.  However, lingering moisture will still allow for sct aftn and
early evening showers/storms across the higher terrain mainly along
and south of I-70 and across South Park.  Although PW`s values will
be lower today, a few storms may still produce locally heavier
rainfall.  Across the plains expect dry conditions with warmer
temperatures as readings rise into the mid to upper 90`s.

For tonight, most tstm activity should end by mid evening over the
higher terrain.  Meanwhile outflow boundaries from higher terrain
activity could trigger a few evening showers/storms across wrn
portions of the I-25 Corridor from Denver south across the Palmer
Divide.

For Sat and Sun, an upper level high will be over the area.  As a
result, will see very hot temperatures across nern CO both days,
with Heat Advisory criteria, for the I-25 Corridor. Highs will be
in the upper 90`s to lower 100`s. Record highs could be broken in
some locations both days. As far as tstm chances, latest data
continues to show a gradual increase in monsoon moisture from Sat
into Sun with slowly rising PW values. Thus will see a gradual
increase in tstm activity over the higher terrain with slow moving
storms and locally heavy ranfall possible especially by Sun.
Across the plains, outflow boundaries from tstms over the higher
terrain may trigger some widely sct tstms both Sat and Sun during
the late aftn/early evening hours along the I-25 Corridor.

Looking ahead to Mon thru Wed of next week, the upper level high may
shift slightly southward.  As a result, this will allow for monsoon
moisture to move across the area with weak disturbances likely
embedded in the mid level flow. PW`s will be 150% to 175% percent
above normal. Overall, there will be a good chance of showers and
storms each aftn and evening across the area, based on the latest
data. Meanwhile, temps won`t be quite as hot during the period
but readings will still remain mostly in the 90`s over nern CO.

&&

.AVIATION /06Z TAFS through 06Z Saturday/...
Issued at 1108 PM MDT Thu Jul 23 2026

Lingering showers/isold tstms had ended late this evening with no
additional activity expected overnight. Winds have become drainage
and will remain that way overnight. On Fri, winds will go light
and variable by 14z and then become NE by 17z.  By 23z winds will
shift to more easterly and then southeast by early Fri evening.
At this time don`t expect any shower/tstm actiivty Fri aftn. There
is a 10% percent chance of an isold shower/tstm at BJC early Fri
but activity should stay to the west of APA and DIA.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM to 9 PM MDT Saturday for COZ038>040-043.

Heat Advisory from 11 AM to 9 PM MDT Sunday for COZ038>040-043.

&&

$$

DISCUSSION...RPK
AVIATION...RPK

NWS BOU Office Area Forecast Discussion