085
FXUS63 KDMX 221749
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
Issued by National Weather Service North Platte NE
1249 PM CDT Wed May 22 2024

 ...Updated for the 18z Aviation Discussion...

.KEY MESSAGES...

- Gusty winds continue but steadily diminish through the
  morning hours.

- Few light showers and sprinkles possible today, with the
  potential for some brief gusty winds with any healthier
  updrafts.

- Additional thunderstorm chances late Thursday into Friday
  morning, then again on Sunday.

&&

.DISCUSSION...
Issued at 340 AM CDT Wed May 22 2024

>> Breezy Winds Continue This Morning

After the events of the last few days, we get a much needed breather
through the next two days, before more chances for thunderstorms
arrive late Thursday night into Friday morning. Although
conditions are currently dry across the state, gradient winds
have been quite strong through the night and into early this
morning. These are associated with the departing surface low
pressure and the cold air advection funneling in behind it. Low
stratus clouds have also been present through much of the
night, which has helped to inhibit the development of a surface
inversion and allowed wind gusts to linger through much of the
night. Fortunately, as the low has continued northeast and
cloud cover cleared, winds have started to diminish over
southern and southeastern Iowa. Expect this downward trend to
continue through the morning hours for more locations as the
system departs. Winds may be breezy in northern Iowa again
today, but not nearly to the extent of yesterdays gusts.


>> Quieter Through Mid-Week

As mentioned above, today and Thursday will provide a brief break
from the active weather. However, a second PV anomaly passing
through today may spoil our hopes of staying completely dry
through Thursday. Most of the gulf moisture will be cut off from
this wave, which will inhibit rain chances considerably.
However, there have still been indications in high resolution
guidance that a few isolated to potentially scattered showers
may kick off as it passes through Today, primarily due to a
lobe of mid to upper level moisture confined to the wave. This
moisture aloft will still have to fight its way down to the
surface, with forecast soundings indicating a dry vertical
profile with a nearly 10-15F T/Td spread at the surface this
afternoon. That all being said, the final nudger to include
some low end precipitation chances in the forecast came down to
the presence of roughly 500 to 1000 J/kg of CAPE in the
afternoon. If realized, this would certainly aid parcels in
overcoming the dry air near the surface. Likewise, if a
convective shower or storm were to develop and rain into the dry
air below it, brief wind gusts could develop. Of course, thats
all dependent on IF anything can be lifted enough to take
advantage of the instability and then also find enough moisture
to precipitate. Therefore, would expect isolated showers at
best, with sprinkles and virga being the more likely outcome
across the area.


>> More Shower and Storm Chances This Weekend

Conditions look dry through most of the day Thursday, but another
upper level wave will begin to influence the area as early as
Thursday night and last into Friday morning. While this system
doesnt look to be anywhere near as loaded as yesterdays,
there will still be modest amounts of instability and shear as
it passes through. A few stronger storms will be possible, but
the timing of the system passage will help to mitigate our severe
risks some. These do still have the potential to produce some
efficient rainfall, with 1.5+ PWATs and persistent moisture
transport near the surface and aloft. While there will be time
for rivers to recover through the week after the recent
rainfall, this could slightly delay the receding river levels
for a few sites. However, not anticipating this to induce any
flooding issues at this time, especially with the progressive
nature of the storms, just something to keep an eye on as we get
into the high resolution window.

Shortly after the late Thursday into Friday system, another low
pressure system lifts out of the southwest US on Sunday
bringing more rainfall chances to the state. Any severe risk
looks to stay south of us at this time, but will continue to
evaluate this system as it draws closer in the coming days.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 1115 AM CDT Wed May 22 2024

VFR conditions are expected to prevail the next 24 hrs across
IA. A few fair weather cumulus clouds will be around this
afternoon, with some increase in mid and high level cloudiness
tonight. Winds will be gusty from the west this afternoon. Winds
will decrease and become light south tonight.

&&

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

&&

$$

DISCUSSION...Dodson
AVIATION...Taylor