Area Forecast Discussion
Issued by NWS Des Moines, IA

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069
FXUS63 KDMX 112325
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
625 PM CDT Sat May 11 2024

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- Picture-perfect Spring Day today.

- Shower and thunderstorm chances return to the forecast late
  Sunday afternoon and through Monday.

- Additional thunderstorms by late week.

&&

.DISCUSSION...
Issued at 235 PM CDT Sat May 11 2024

If you`re looking for a glorious spring Saturday, this is it. Clear
skies, temperatures in the mid to upper 70s, and a nice breeze. This
nice stretch Friday and today is owed to a departing trough to the
east and and incoming cut-off low to the southwest. Caught in
between, Iowa has enjoyed a rare quiet stretch in what has been an
active few weeks. And while Sunday will begin nicely, this comes to
an end.

By Sunday afternoon the cut-off low lifts out of the southwest and
into the midwest. Showers and thunderstorms will develop across
the area in the afternoon, continuing through the overnight and
on Monday. Flow is fairly weak, in fact in soundings you have
to look above 400 mb to find wind over 20kts. Decent CAPE of
1000-1500 J/kg will be present, but with that weak flow in place
storms will struggle to organize so the severe threat is quite
low. With such weak flow, storm motions will be exceedingly
slow which could lead to pockets of heavier rain. At the same
time, the system is battling dry air, especially across northern
Iowa, which will likely mitigate some of the heavy rain
potential. The low will pass to the south on Monday with showers
and thunderstorms mainly central and south, ending by Tuesday
in the southeast.

Quickly on it`s heels comes the next system, a trough dropping
across the Rockies and into the midwest on Wednesday into Thursday.
despite some model differences at this time range, for now showers
and storms associated with the passage look to remain sub-
severe with the main instability axis pushed south of the area.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 625 PM CDT Sat May 11 2024

VFR conditions expected this period. Some increase in mid to
high level clouds aft 18z Sunday; especially FOD/DSM as next
storm approaches. Winds remain under 10kt through 14z most
locations with some mixing aft 14z; occasional gusts to 15 to
19kt. Sct showers/iso thunder coverage aft 21z, if any, will be
too sparse to include mention this period. /rev


&&

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

&&

$$

DISCUSSION...Hagenhoff
AVIATION...REV