120
FXUS63 KDMX 071130
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
630 AM CDT Thu May 7 2026

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

.KEY MESSAGES...

- Patchy, low-lying frost for a few hours 3 to 7 am this morning.

- Several chances for showers and thunderstorms through early
  next week. No apparent signal for significant severe weather
  or heavy rainfall with any storm chances.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 258 AM CDT Thu May 7 2026

A look at the current pattern features the continuation of mid-level
troughing across the Great Lakes into Canada, while over the western
CONUS, ridging is building. An embedded shortwave currently over the
Dakotas is slated to track southeastward, passing over Iowa later
today. Weak forcing and mid level moisture ahead of this feature
though has led to areas of clouds in the mid-levels over southern
Minnesota down through at least the northern half of Iowa. Localized
returns per recent radar scans is indicated mainly over southern
Minnesota into far northern Iowa, though the presence of notable low
level dry air is keeping surface conditions dry. The expectation is
that this activity will continue to move southeastward across
northern into eastern Iowa this morning, with dry air remaining
overhead keeping conditions dry. Regarding temperatures, values are
currently reading in the mid 30s to mid 40s, lowest over far
northern Iowa and portions of western Iowa, paired with light and
variable winds. Despite the cloud cover moving over the state,
continued cooling is expected before sunrise, with lows falling
largely in the mid to upper 30s. While the clouds are limiting
widespread frost formation, isolated frost is possible still this
morning, mainly over portions of northern and western Iowa.

Low level southwest flow increasing into Iowa for today will lead to
warming conditions, as forecast highs are expected to top out in the
mid to upper 60s. This afternoon into the early evening, boundary
layer mixing and elevated instability aloft mainly over central to
southern Iowa will lead to breezy conditions and cumulus
development, with CAM guidance continuing to also suggest rain
shower development. However, low level dry air per soundings looks
to stay put, while forcing looks to be more pronounced, maximized
further east towards Illinois. Cannot rule out the potential (<20%)
for virga or sprinkles during this time, along with the possibility
of localized evaporative cooling that would result in occasional
gusty winds possibly reaching up to 35-40 mph. Any activity
diminishes later in the evening, with temperatures dropping off in
the upper 30s through mid 40s by tonight, warmest south and
southwest.

Another shortwave and attendant surface low moving into the region
late tonight into early Friday will bring the next chance for rain
into Iowa. Deeper moisture profiles in the mid-levels, along
with slightly stronger forcing due to an increasing low level
jet maximized over northern Missouri may be able to overcome the
low level dry air that is still indicated over southern to
portions of central Iowa, as the system itself passes just to
the south of the state. At most given the current guidance,
light rain is possible (20-30%) over these areas through the
morning. Dry conditions are expected to return through the
afternoon as the feature departs eastward. Dry air overtakes the
area, especially over northern and western Iowa as PBL mixing
maximizes, where gusts up to 20-30 mph are possible through the
afternoon. The push of warm air continues to end the work week
as the aforementioned western ridge approaches the region. Highs
are expected to reach into the upper 60s to low 70s into the
afternoon, warmest over western Iowa.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 128 PM CDT Wed May 6 2026

Additional shortwaves will move through the region late this week
into perhaps early next week. The rough timeframes and possible
areas for scattered showers and storms are as follows: 1) late
Thursday night into Friday morning, primarily southern Iowa,
2) late Saturday into Sunday morning with chances highest over
southern Iowa, and 3) late Monday into Tuesday over the state.
In all instances, there is no apparent signal for significant
severe weather or heavy rainfall concerns from a pattern
recognition and diagnostic standpoint. Examining the ML/AI
guidance generally supports this idea with EC forced data
pointing to up to 15% chance on Monday/Monday night while the
GFS/GEFS is lower or none. Temperatures in this period will
largely be around if not above normal.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 629 AM CDT Thu May 7 2026

Areas of mid-level cloud cover will continue to drop southeast
across Iowa this morning, followed by cumulus development for
most areas this afternoon that will likely lead to similar
ceilings. VFR conditions are however expected to remain across
the terminals through the period. There is a low chance for
sprinkles this morning, as well as this afternoon over southern
Iowa, though given low confidence on exact coverage have kept
out of the terminals. Variable winds this morning will turn
southwesterly for most sites into the afternoon, while
northwesterly across northern terminals, with gusts highest
south up to 20 knots. Variable but light winds return into the
evening, then shift south/southeasterly into Friday morning.

&&

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

&&

$$

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