471
FXUS63 KDMX 022329
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
629 PM CDT Tue Jun 2 2026

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

.KEY MESSAGES...

- Dry conditions continue today and Wednesday, with breezy winds
  possible north and west on Wednesday.

- Rain chances increase late Wednesday night into Thursday,
  beginning over northwest Iowa then slowly progressing south
  and east through Thursday. A few severe storms are possible
  Thursday afternoon and evening.

- Shower and storm chances continue into Friday, with more
  chances for strong to severe storms with heavy rain through
  Friday evening.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 247 PM CDT Tue Jun 2 2026

The surface high over the Great Lakes region has full control
over the weather in Iowa today, as clear and dry conditions
prevail. Soundings over the state echo this, showing over a 15C
T/Td spread through the entire layer from the surface up to 350
mb. With the dry profiles, the boundary layer has mixed out well
today allowing for some breezier winds east southeast winds to
develop. This is especially true over northwest Iowa where
surface pressure gradients are slightly stronger. Dry conditions
continue overnight, with any rain chances expected to remain
well to the west of the area through Wednesday morning.

Our high pressure to the east will maintain it`s influence in
the state during the day Wednesday, keeping most of the area
dry. However, the high will be progressing south and eastward
through the day, flipping surface flow to southerly and allowing
more moisture to work into the state from the south and west.
With these increasing surface temperatures and dewpoints, we`ll
begin to see the more unstable airmass to our west also work
it`s way into western Iowa through Wednesday. This may allow for
an isolated shower/thunderstorm in the far western/southwestern
reaches of the area, but coverage should be minimal with the
dry air still holding over most of the area. Instability could
be sufficient for a few stronger updrafts and dry sub-cloud air
could enhance downdraft winds, but shear will be weak and storms
likely disorganized. Therefore, any severe threat will be low
on Wednesday. Aside from low (less than 15%) precipitation
chances Wednesday, tightening pressure gradients from low
pressure encroaching from the west will allow for breezy
conditions with wind gusts of 20 to 25 kts.

By Wednesday night, the moisture axis will have finally pivoted
into western Iowa, bringing better chances for showers and
thunderstorms overnight and mainly into Thursday morning. This
activity will originate in Nebraska and South Dakota along a
boundary, but eventually evolves into more scattered
precipitation being fueled by the weak low level jet and theta-e
advection now passing through the state. This moisture
advection will keep scattered showers and storms over the
northwest portions of the area through the day on Thursday,
progressively tracking farther south and east into the evening
and overnight hours. It`s worth noting that precipitation
chances are in place all day Thursday, but rain will be
scattered and likely not a complete washout. Instability will be
increasing during the day on Thursday as well, which could open
up the potential for a few stronger storms in the afternoon.
This of course will depend on the degree of destabilization, but
1000+ J/kg of MUCAPE could certainly develop in areas that are
able to clear out during the day. This could allow for a few
strong to severe storms on Thursday, although the marginal deep
layer shear around 25 to 35 kts may somewhat limit storm
organization. The storm prediction center has placed a marginal
risk (level 1 of 5) for severe weather over the northwestern
half of Iowa for Thursday. PWATs on Thursday will also be in the
1.5 to 1.6 range, which is near the 90th percentile of PWAT
climatology for early June. Therefore, showers or storms could
produce some efficient rainfall. This rainfall will be much
needed given our recent dry spell, but prolonged rain in a short
time could still lead to localized ponding impacts, mainly in
urban areas.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Issued at 247 PM CDT Tue Jun 2 2026

The 500 mb ridge responsible for our dry mid-week conditions
will be suppressed south and eastward by Thursday night,
transitioning the upper level pattern over Iowa to more of a
southwest to zonal flow pattern. This pattern will have keep
persistent moisture advection up into the state Thursday night
into Friday, leading to additional scattered shower and storm
chances overnight. By Friday afternoon and evening, a shortwave
will drop southeastward into Iowa, bringing additional synoptic
forcing and a cool front. Showers and storms will develop along
this boundary within a moist and unstable environment. Wind
shear on Friday will once again be on the lower end, but with
the boundary passage and upper level support, certainly can`t
rule out more strong to severe storms late Friday into the
evening. Likewise, a high PWAT environment (1.6 to 1.7") will
still be in place ahead of this boundary, resulting in another
round of efficient and potentially widespread rainfall. Again,
our dry spell should allow us to handle most of this, but rain
falling in similar areas over multiple days could lead to some
localized hydro concerns into the weekend.

Through Saturday and Sunday, a brief period of upper level
ridging will bring warmer and somewhat drier conditions over
Iowa, although shower and storm chances could still linger over
the southern portions of the area. This reprieve looks fairly
brief, as Sunday night into the beginning of next week could see
another wet pattern develop.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 629 PM CDT Tue Jun 2 2026

VFR conditions are forecast and no aviation impacts are
anticipated. Winds are diminishing this evening and will turn
from ESE to SSE by Wednesday morning, then increase again
during the day with gusts to around 15-20 KT at times.

&&

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

&&

$$

SHORT TERM...Dodson
LONG TERM...Dodson
AVIATION...Lee