Area Forecast Discussion
Issued by NWS Des Moines, IA

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687
FXUS63 KDMX 032006
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
306 PM CDT Wed Jun 3 2026

.KEY MESSAGES...

- Dry conditions continue through tonight; then storms arrive
  far northwest after midnight.

- Marginal Risk (level 1 out of 5) of severe weather Thursday
  afternoon/evening.

- Rain/storm chances continue into Friday evening with the
  possibility of severe weather and heavy rain. Slight Risk per
  SPC.

- Temperatures return to the upper 80`s over the weekend.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 257 PM CDT Wed Jun 3 2026

Dry, warm, and breezy conditions are common across Central Iowa
today, with afternoon temperatures as of 2pm in the upper 70s to low
80s and south/southeasterly winds gusting to 20-25 mph, while areas
on northern Iowa have seen higher gusts at times up to 30-35 mph.
The synoptic setup responsible for this weather features a large
area of ridging and associated surface high pressure that is
centered over the Ohio Valley, with its influence remaining across
Iowa, while further west, a trough is moving across southern
Saskatchewan/Manitoba. The high pressure area will continue to allow
for dry conditions through the rest of today, though will continue
to depart eastward into the evening/Thursday morning. Will see a
noticeable change as moisture return as it increases across western
Iowa tonight, which will continue to translate further north and
east over the next few days and generally bring a more active
pattern across Iowa into the weekend.

The first chance for showers and storms in the short term will come
from a boundary in relation to the Canadian trough mentioned above,
which is slated to arrive into northwest Iowa after midnight tonight
and drop southeast into the state through the morning. Showers and
storms are expected to arrive in relation to this boundary, but will
be on a weakening trend as they track out of the Dakotas/Nebraska.
The parameter space over Iowa features instability values less than
500 J/kg and shear values under 25 knots, which should keep any
storms that linger into Iowa below severe limits. With dry air still
over much of central and eastern Iowa, any showers and storms will
generally struggle to maintain themselves as well, but could hold
the potential for gusty non-severe winds as they collapse.

By late Thursday morning and especially the afternoon,
destabilization becomes widespread overhead, with instability values
around 1000-2000 J/kg, paired with shear values around 25-30 knots
as temperatures rise through the 80s. These conditions, paired with
the arrival of a shortwave moving northeast across Iowa and further
forcing for lift into the evening by the strengthening low level jet
will allow for scattered showers and storm chances to return across
western and southern Iowa, increasing in coverage through the
evening as this activity tracks northeastward. The primary hazards
of concern will be hail and gusty winds, though heavy rain continues
to be increasingly likely as well where storms pass through, given
very favorable PWATS of 1.6-1.7 inches moving over much of the area.
Though soils over much of the state are dry, quick accumulations of
1-2+ inches could easily occur where stronger storms setup. A Slight
Risk per WPC has been introduced over portions of southwest/western
Iowa to account for this potential.

Highest dewpoints in the mid to upper 60s arrive over much of Iowa
into Friday as moisture advection from the Gulf becomes maximized.
Showers and storm coverage look to remain through the majority of
Friday morning as the low level jet slowly fades, especially over
southern Iowa. While the severe risk is lessened during the morning
hours given more limited instability overhead, storms are still
expected to occur. Drying conditions return briefly, but will see
storm chances return once again Friday afternoon and especially the
evening as another mid-level shortwave is expected to pass across
the Upper Midwest, with an associated defined cold front arriving
into Iowa. This west to east boundary will be the feature
responsible for yet another period of showers and thunderstorms,
which will gradually track south/southeast with the passing boundary
through Friday night. Higher instability values ahead of this
feature around 2000+ J/kg, shear values up to 30-35 knots and steep
lapse rates of 7-8 C/km overhead will lead to the highest potential
for strong to severe storms. A Slight Risk for severe weather
remains across much of the forecast area per SPC given this
parameter space, where all hazards are possible. Heavy rain given
similar PWAT values and slower storm movement will introduce
additional concerns for 1+ inch amounts where stronger and repeated
storms move through.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Issued at 257 PM CDT Wed Jun 3 2026

Showers and thunderstorms are expected to continue into Saturday
morning, mainly over southern Iowa in relation to where the frontal
boundary is progged to generally stall for the day. While most areas
look to be dry for much of the day, additional showers and storms
look to redevelop over parts of southern Iowa in relation to the
lingering aforementioned front by the evening. Confidence however on
exact placement is on the low end at this time, as models such as
the GFS push this boundary near the IA/MO border into northern
Missouri by Saturday evening. Certainly some placement
differences to keep an eye on over the coming days. The pattern
Sunday and beyond looks to remain on the more active side as
additional wave pass through the area, along with slightly
warmer temperatures overhead. More specific details however on
timing and location of showers and storms will be better known
in the coming days as models better capture these features.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1246 PM CDT Wed Jun 3 2026

VFR conditions are expected to remain across the terminals
through the period. Breezy winds will remain through the
afternoon, decreasing into the evening out of the
south/southeast, before switching southwesterly late in the
period and becoming breezy again. Some areas of cumulus will
remain through the early evening, mainly west and north before
dissipating. However, an increase in clouds is expected into
Thursday in the mid-levels. A boundary passage into northwest
Iowa after 06z will introduce low chances for some showers and
perhaps a few storms, with chances included mainly at KFOD and
KMCW at this time. Dry air further east lowers confidence
elsewhere but will monitor trends and update accordingly.

&&

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

&&

$$

SHORT TERM...Bury
LONG TERM...Bury
AVIATION...Bury