405
FXUS63 KDMX 281141
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
641 AM CDT Tue Jul 28 2026

 ...Updated for the 12z Aviation Discussion...

.KEY MESSAGES...

- Significant heat relief arrives today with highs in the upper
 80s to lower 90s.

- Mainly dry conditions prevail through Wednesday.

- Shower and storm chances (60-80%) return by Thursday
  afternoon.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 257 AM CDT Tue Jul 28 2026

Showers and storms are currently positioned over in eastern/central
Nebraska this morning, though they are expected to weaken as they
track southeastward. Far southwest Iowa could see an isolated shower
or storm overnight into early Tuesday morning, but a passing
boundary will work to shunt this complex and the better instability
south of the area.

Aside from the slight chance for a stray shower in far southwest
Iowa this morning, the main story is the end of the extreme heat for
central Iowa. Relief has finally arrived and looks to stick around
through much of the week. Highs today will top out in the upper 80s,
which is roughly 10 degrees cooler than Monday. Dew points will also
fall into the upper 60s to lower 70s, providing a noticeable drop in
humidity. While it will still be a warm day, heat indices are only
expected to peak in the lower 90s... a welcome change from the 110
degree day we saw yesterday.

A few models try to initiate a spotty shower or storm in far
northwest Iowa during peak daytime heating today, but lack of deep
moisture should cause any convection to struggle to maintain
strength. Temperatures may tick upward slightly on Wednesday as
a western ridge shifts eastward, potentially bringing a few
locations back to the lower 90s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 246 PM CDT Mon Jul 27 2026

Warm and humid conditions continue through Friday before a pattern
change starts to take place. The 500mb ridge that Iowa sits on the
periphery on begins to shrink and move to the west. Temperatures
through most of the long-term will be cooler, with highs generally
in the 80s and overnight lows falling into the 60s across much of
the state. The long term looks to be fairly dry as well. There are
some lower thunderstorm chances Wednesday night into Thursday as a
shortwave is expected to ride overtop of the ridge. Most of the
activity should be out west in Nebraska. The placement of the
shortwave as it moves through will be better assessed tomorrow and
Wednesday. Thursday night, a low develops over the Dakotas and will
move to the east. This low will drive higher shower and thunderstorm
chances as it moves through, bringing with it a cold front, leading
to much lower temperatures than we`ve seen to start the weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 630 AM CDT Tue Jul 28 2026

VFR conditions are expected to prevail through the end of this
TAF period. Mostly cloudy to overcast skies across central Iowa
this morning will clear heading into the afternoon, giving way
to mostly clear skies. Winds will remain light out of the east
to northeast under 10kts. Have opted to omit smoke from TAF
mentions as no visibility restrictions are expected. Patchy fog
will be possible towards the end of this TAF period.


&&

.DMX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...TDR
LONG TERM...67
AVIATION...TDR