338
FXUS65 KBOU 221743
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1143 AM MDT Wed Jul 22 2026

.KEY MESSAGES...

- Storm coverage and intensity increases today and Thursday as
  monsoonal moisture moves into the region. Storms from today
  onward will be capable of producing locally heavy rainfall along
  with a localized threat of flash flooding.

- Storm coverage expected to decrease again by Friday into this
  upcoming weekend, although mountain areas should see at least
  scattered storm coverage each afternoon and evening.

- Temperatures will rise back into the upper 90`s to lower 100`s
  over northeast Colorado for the weekend into early next week.

&&

.DISCUSSION /Through Tuesday/...
Issued at 250 AM MDT Wed Jul 22 2026

For today, will continue to see monsoon moisture moving across the
area as the main upper level high is centered to the southeast of
the area.  PW`s across the high terrain will be from 150% to 200%
above normal so expect areas of heavier rainfall during the aftn
with the stronger storms.  Across the plains, the low level flow
will be SSE with a Denver cyclone expected by aftn. Should see tstms
develop along the associated convergence zone with storms moving
slowly to the east across the plains from late aftn thru the
evening hours. Additional storms may also develop along the I-25
Corridor as outflow boundaries move across from the higher
terrain. Once again, with PW`s aoa 150% of normal, expect some
areas of heavy rainfall. SBCAPE will range from 1500-2000 j/kg
over the plains but overall shear will be fairly weak. However,
can`t rule out an isold marginal svr storm or two. Highs this
aftn, will remain in the upper 80`s to mid 90`s over nern CO.

For tonight, a weak upper level trough will move into wrn CO which
may allow for showers and a few tstms to continue over the higher
terrain overnight.  Across the plains, should see a decrease in
shower/tstm activity by midnight.

On Thu, monsoon moisture will continue over the area as the weak
upper level trough moves across the area.  PW`s are still fcst to be
from 150% to 200% above normal.  Thus should see another round of
showers and storms across much of the area with areas of heavy
rainfall. Highs on Thu will be in the mid 80`s to lower 90`s across
the plains.

Looking ahead to Fri and Sat, the upper level high will gradually
build back into the area as monsoon moisture decreases.  As a
result, will see tstm activity become more sct over the higher
terrain with only a slight chc of storms over the plains both days.
Highs will be warmer as well, as readings rise back into the
upper 90`s to lower 100`s, across the plains by Sat.

For Sun into Mon, an upper level high will extend from the Great
Basin across Colorado.  The ECMWF and GFS are in better agreement
tonight, with regards to whether there will be another surge of
monsoon moisture moving into the area. Both models now show
monsoon moisture affecting the area both days, especially across
the higher terrain. Meanwhile temperatures will remain in the
upper 90`s to lower 100`s for highs across nern CO.

&&

.AVIATION /18Z TAFS through 18Z Thursday/...
Issued at 1136 AM MDT Wed Jul 22 2026

Convection this afternoon remains the primary concern of the TAF
period. KDEN recently reported an observation of 87F/55F, with
ACARS soundings showing MLCIN quickly decreasing across the metro.
Continued destabilization is likely over the next couple hours,
with convection likely to develop sometime between about 20-22z.
Forecast soundings would suggest the potential for at least some
brief TSRA/+TSRA at the terminals, with relatively high confidence
that this would occur sometime between 22-01z this afternoon.
Scattered showers or a few thunderstorms could continue into the
evening hours.

Some guidance is fairly bullish on developing low stratus late
this evening (~05z), with that potentially continuing through the
overnight hours. This looks like it would be highly dependent on
today`s convection, so at this time the only change was to add in
a FEW010 group to DEN for most of the night.

A reasonably similar forecast pattern is expected tomorrow.
Guidance continues to advertise a favorable environment for slow
moving SHRA/TSRA tomorrow afternoon, with the best chance of any
storms coming after 21z Thursday.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion