131
FXUS63 KDMX 221052
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
552 AM CDT Mon Jun 22 2026

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

.KEY MESSAGES...

- Showers and drizzle ending by evening, temps in the 50s
  overnight.

- Partly to mostly cloudy on Monday. A stray shower is possible.
  Highs in the 70s.

- Next chance for showers and thunderstorms is late Tuesday
  afternoon into Wednesday morning. An isolated strong/severe
  storm is possible. Below average temperatures will continue
  for most of this week with highs in the 70s to lower 80s.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 153 PM CDT Sun Jun 21 2026

The rainfall event will continue to wind down this afternoon
into this evening, and the Flood Watch was cancelled around 1pm.
Weak upper forcing and lingering moisture convergence will allow
for light showers or drizzle to persist in the east through
late this afternoon. The highest storm total rainfall amounts
ranged from 2" to 3" over portions of southern and central Iowa,
which is actually pretty impressive considering the lack of
convective elements and virtually no lighting. A few rivers are
experiencing within bank rises, but no river flooding is
currently anticipated. With the abundant cloud cover and
rainfall, temps struggled to move today, with readings remaining
in the 60s in most places as of 2pm. In fact, these readings
are very close to the record "low max" temps for the date (DSM
is 63F, ALO is 62F. both from 1902). Not the greatest conditions
for Father`s Day, sorry to all Dad`s out there!

Tonight, sfc high pressure will build into Iowa resulting in light
and variable winds. Depending on the amount of clearing, the light
winds and residual low level moisture is a favorable setup for at
least patchy fog to develop. Guidance is not terribly bullish
attm, but something will need to monitor this evening.

Monday...the sfc high remains in place over IA and much of the
Midwest with upper level shortwave ridging developing by afternoon.
Model soundings and time sections show a "dirty" look, with
moisture remaining in both low and mid-levels. Thus, expecting a
partly to mostly cloudy day with a coolish highs in the 70s.
Several CAMs (e.g. HRRR) due try to develop isolated showers
tomorrow afternoon as very modest instability develops. These
rogue showers would be most likely across northern Iowa.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 153 PM CDT Sun Jun 21 2026

The synoptic pattern this week will begin with a predominately
northwest upper flow regime over the upper Midwest and Corn Belt,
with upper ridging along the west coast and the development of
a broad trough along the far northern CONUS.

On Tuesday, a weak sfc low will develop over ND/MN with a weak cold
front trailing swd into the Plains. Much of Tuesday will be dry, but
modest moisture return ahead of the front may produce
weak/moderate instability by late afternoon into the evening,
especially across northern/western Iowa. This will lead to a 30-60%
chance of showers/storms, mainly after 00Z Wed. The SPC has
introduced a Marginal Risk (Level 1 of 5) for late Tuesday. Thinking
the best chance for severe weather is likely north and west of this
forecast area (supported by latest AI Guidance) but something to
monitor. Highs on Tuesday will remain in the 70s.

Mainly dry conditions are expected Wednesday and Thursday, and with
the persistent northwest flow, temperatures will remain below
average. The next precipitation chances arrive Friday into the
weekend as additional low amplitude shortwaves track through
the region. There are the usual timing/placement uncertainties
at this timeframe, so the typical 20-40% PoPs seem reasonable
for now. By the weekend, a deeper upper trough is forecast to
develop over the western US, resulting in a transition to a
more southwest upper flow. This will usher in a more typical
warm and humid summer pattern with highs rebounding back to near
or above normal - 80s to lower 90s.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 547 AM CDT Mon Jun 22 2026

Dense fog has held on near ALO, so delayed improvements in the
next 6 hours, also accounting for it lifting to stratus in the
early morning. Elsewhere, cameras show patchy, shallow fog that
may vary in between VFR and MVFR for the first hour or two. VFR
conditions anticipated beyond, but with a cumulus deck that will
hover close to 3kft to start. An early BKN deck can`t be ruled
out.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 7 AM CDT this morning for IAZ026>028-
037>039.

&&

$$

SHORT TERM...Fowle
LONG TERM...Fowle
AVIATION...Jimenez