707
FXUS63 KDMX 210358
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1058 PM CDT Thu Aug 20 2026

 ...Updated for the 06z Aviation Discussion...

.KEY MESSAGES...

- A few isolated storms skim northern Iowa overnight tonight.

- Additional thunderstorms in southwest Iowa Friday evening and
  overnight.

- Mostly dry and sunny through the weekend!

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 222 PM CDT Thu Aug 20 2026

High pressure has allowed for tranquil conditions across the area
today with a few diurnally driven clouds in southern Iowa.
Farther north a shortwave is moving across the upper midwest,
resulting in a few thunderstorms across Minnesota. A few high
clouds have moved across northern Iowa associated with this
wave. The cold front trails across South Dakota and into
Nebraska this afternoon and will move east, pushing across Iowa
overnight and on Friday. Better forcing will be across Minnesota
near the surface low and scattered thunderstorms are expected
there, extending along the front. A few of these may skim
northern Iowa overnight. While an isolated stronger storm is
possible, these will largely be confined north and west of the
area where forcing and instability are better phased.

Much of Friday will then be dry with northwest flow helping to
bring high level smoke from fires across the Pacific northwest.
Another embedded wave riding along the western US ridge will
slide across Nebraska and southwest Iowa Friday evening. This
will bring another chance for scattered thunderstorms. Forcing
is again modest and focused largely west of the area, but with
1500+ J/kg MLCAPE and 40 kts of shear, a few stronger to severe
thunderstorms are possible in the evening.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Issued at 222 PM CDT Thu Aug 20 2026

Any lingering storms in far southern Iowa should clear out early
Saturday morning with dry conditions through the weekend. Another
embedded shortwave will move across Iowa late Sunday evening into
Monday, slowing from model solutions 24 hours ago.  The upcoming
work week looks to remain active with embedded shortwaves continuing
to ride along the western US ridge with northwest flow across Iowa.
A more robust system looks to move across the area on Tuesday and
will be the next opportunity for more organized convection. At this
time range differences remain with the GFS favoring a southerly
track over the Euro northerly track.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1052 PM CDT Thu Aug 20 2026

VFR conditions ongoing and expected to continue through the TAF
period. Few showers and isolated storms are starting to skim far
north and northeast sections mainly north of KMCW and KALO.
There`s still a low chance for a shower to impact either site
with slightly higher chances at KMCW than KALO. Added shower
mention into KMCW prior to start of 06Z TAFs with upstream
activity expected to weaken so no mentions at either site after
06Z. High level smoke may keep skies hazy on Friday. Some
additional showers/storms are possible into Friday morning but
chances are generally less than 30% so did not include any
mentions with low confidence. Similarly, may also see some
storms in southwest or southern Iowa in the afternoon to early
evening, but south and west of TAF sites. Winds out of the south
tonight become out of the west to northwest during the day
Friday.


&&

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

&&

$$

SHORT TERM...Hagenhoff
LONG TERM...Hagenhoff
AVIATION...05