395
FXUS63 KDMX 181928
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
228 PM CDT Mon Aug 18 2025

.KEY MESSAGES...

- Storms redevelop tonight along the front in east central to
  southeast Iowa. A few stronger storms may produce gusty winds.

- Patchy fog development possible Tuesday morning, mainly north.

- Cooler and dry through the rest of the week with highs in the
  low to mid 80s. Even cooler by this weekend.

&&

.DISCUSSION...
Issued at 228 PM CDT Mon Aug 18 2025

Widespread showers and thunderstorms across the area this morning
dissipated quickly by midday. Cloud cover has also dissipated in
many locations, and in areas along and south of the boundary this
has made for another muggy afternoon. Temperatures have warmed into
the mid to upper 80s with dewpoints in the 70s. Meanwhile, central
to northern Iowa has remained in the low to mid 70s through the
afternoon.

Early this afternoon cumulus has grown along the boundary draped
across east central in south central Iowa. Expect this to
become more robust in the next few hours with diurnal heating.
This will be the impetus for convective redevelopment through
the evening. By 2 pm a few isolated showers were already
beginning to develop on radar. Conditions across southeast Iowa
where the boundary will traverse are nearly uncapped with
MLCAPE values of 3000+ J/kg. Despite the deeply unstable
conditions, shear is virtually nonexistent in this area which
will inhibit more organized storm development. Expect that
storms will likely develop quickly and then collapse, with these
collapsing core producing gusty winds as the primary convective
hazard. This will be confined to southeast portions of the area
as the boundary continues to sink south and east this afternoon
and evening.

After convection clears the area this evening expect a quiet
evening. By Tuesday morning patchy fog develop is possible across
the area, especially across northern Iowa. The past several mornings
have seen isolated fog development north of the boundary in cooler
air and this is likely to continue on Tuesday morning. Temperatures
Tuesday through the end of the week with be in the low to mid 80s
with dewpoints in the 60s, feel more comfortable than this past
weekend. A quick moving cool front Friday will bring another
chance for precipitation and cooler temperatures further with
highs in the 70s by the weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1240 PM CDT Mon Aug 18 2025

Showers and thunderstorms have come to an end this morning with
lingering cloud cover becoming more scattered this afternoon.
Later this afternoon thunderstorms redevelopment is expected in
east central to southeast Iowa, however at this time it appear
much of this should miss TAFs sites. Should development become
more robust than currently expected this would be near
KOTM/KDSM. Later tonight into Tuesday morning fog development is
anticipated across northern to northeast Iowa with IFR to LIFR
conditions possible at sites KFOD/KMCW/KALO.

&&

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

&&

$$

DISCUSSION...Hagenhoff
AVIATION...Hagenhoff