738
FXUS63 KDMX 221057
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
557 AM CDT Wed Jul 22 2026

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

.KEY MESSAGES...

- Cooler temperatures in the upper 70s through the work week
  before another warmup into the 90s this weekend.

- Spotty showers possible in southwest Iowa today, then more
  widespread rain Thursday evening into Friday in central to
  southern Iowa.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 207 AM CDT Wed Jul 22 2026

High pressure has settled across the Dakotas and Minnesota,
keeping the area clear and dry, while a surface low sits across
western Nebraska early this morning. The low will gradually
shift east through today with precipitation reaching western
Iowa later this afternoon. High pressure is creating a fairly
dry air mass across Iowa and the incoming low will struggle to
saturate. While a few spotty showers are possible in far
west/southwest Iowa this afternoon most of the area will remain
dry today. That high pressure will also be effective in keeping
the area around 10 degrees below seasonal average with highs in
the upper 70s this afternoon.

Cooler temperatures in the upper 70s continue on Thursday and
Friday. On Thursday an embedded shortwave rides along the western US
thermal ridge, sliding across Nebraska and into Iowa by Thursday
evening. The plume of moisture transport shifts back into Iowa
aided by the increasing low level jet , helping to saturate
sounding profiles by Thursday evening. Precipitation is expected
to last through the overnight and into Friday morning before
clearing out in the afternoon. Warm cloud layers are very deep
at 4000-4500+ with PWATs at 2-2.25" which will likely result in
efficient rain production. Mature crops should be able to handle
several inches of rain, but heavier amounts in town could
result in hydro problems overnight and on Friday morning.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 210 PM CDT Tue Jul 21 2026

A stronger wave looks to move across the top of the ridge by
Thursday evening and bring us our next chance for meaningful precip.
Instability will be quite limited so severe weather is unlikely,
though some thunder is possible Thursday night into Friday morning
in southern Iowa. The nocturnal LLJ returns to our vicinity during
the Thursday overnight, with the nose centered over southwest Iowa.
This should erode the dry air and allow the quite saturated mid
levels to rain down to the surface. The main story will be QPF
amounts. WPC has southwest Iowa in a marginal ERO for Thursday and
Friday, and PWATs are well over 2 inches. There is a large QPF
spread across the models, but a few give spots in southern Iowa 1-2
inches of rain. By the weekend, the ridge intensifies over the
Dakotas, bringing us another period of heat. We may breach the 90s
again on Saturday, and Sunday/Monday look to be the warmest as a
more substantial EML is advected in.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 557 AM CDT Wed Jul 22 2026

VFR conditions will prevail through the TAF period. Diurnal
cumulus is expected to develop midday and diminish after sunset.
Winds will shift this evening, from the north much of the day
and then from the east by around 00z.

&&

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

&&

$$

SHORT TERM...Hagenhoff
LONG TERM...De Bruin
AVIATION...Hagenhoff