textproduct: Des Moines

KEY MESSAGES

- Spotty showers again on Friday, mainly in northern Iowa.

- Frost/Freeze potential is limited to tonight and Friday morning due to cloud cover across the area. More widespread frost/freeze is possible overnight and on Saturday morning with clearer skies and light wind.

SHORT TERM /THROUGH SATURDAY/

Issued at 212 PM CDT Thu Apr 30 2026

A weak embedded shortwave has passed across Iowa today, reaching southeast Iowa early this afternoon. Meanwhile a second wave is across the Dakotas and will drop across Iowa later tonight and on Friday, bringing another chance for scattered showers. Both features are viewable in GOES-East visible satellite this afternoon. This afternoon's wave will continue to push off to the east through the rest of today with increasingly scattered cloud cover. With peeks of sun this afternoon, especially north, gusts of 20-25 mph are expected before sunset with diurnal mixing. Winds relax as we move into the evening hours.

The wave across the Dakotas reaches far northern Iowa late this evening and will slowly move across Iowa overnight and on Friday. This first tangible impact of the wave will be increasing cloud cover across the area. This will reduce chances for better radiational cooling. So while overnight lows will be cool in the mid to upper 30s, do not anticipate widespread frost or freeze conditions through Friday morning. This wave will, however, bring spotty shower chances to the area. First in northern Iowa early Friday morning, then central and southeast as the wave pushes across the state through the day. There is marginal instability, under 100 J/kg, where we could squeeze out a rumble of thunder, though this would be rather sporadic in the scattered shower activity.

High pressure settles in behind this wave, allowing skies to clear and winds fall off Friday night and Saturday morning. This provides a better setup for radiational cooling. Did nudge temperatures down a degree or two on Saturday morning, especially across northern Iowa, however they may need to go lower closer to the dewpoints if winds can go completely calm. With colder temperatures in place, this is a much better setup for frost and freeze conditions.

LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/

Issued at 212 PM CDT Thu Apr 30 2026

Ridging shifts east Sunday into early next week, bringing 70s back to the area. A weak embedded wave skims northern and eastern Iowa on Sunday, which could bring light shower activity to those areas, though expect much of the weekend to be dry for most locations. The main longwave trough pushes towards the central US by early next week, pulling a cold front across the state late Monday into Tuesday, bringing the next round of precipitation to the area. Additional rain chances midweek as this wave slowly pushes off to the east.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1049 PM CDT Thu Apr 30 2026

VFR conditions are expected to prevail through the period. Light sprinkles are possible over the next 6 hours north, but amounts will be minimal and no impacts are expected. Have removed the afternoon Prob 30 shower mention from MCW due to decreasing confidence. Variable winds will become northerly through the morning.

DMX WATCHES/WARNINGS/ADVISORIES

None.