textproduct: Des Moines

KEY MESSAGES

- Spotty, light showers are possible overnight and on Sunday morning, mainly across eastern Iowa.

- Warm Monday, then a cold front brings showers and thunderstorms central and south in the afternoon and evening. A few strong to severe storms are possible.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 230 PM CDT Sat May 2 2026

Clear skies across Iowa this afternoon with light west winds. Meanwhile, a compact surface low has reached North Dakota early this afternoon - viewable in GOES-east visible satellite imagery. This will slide south through the rest of the day and skirt across northern and eastern Iowa overnight and early Sunday morning. A few spotty showers are expected as it moves through, though model soundings show significant dry air in the lowest levels that will limit more widespread shower development. Dewpoint depressions are 20-30+ degrees in many cases with weak instability.

Continued warm air advection into the area on Sunday will send temperatures into the low 70s by afternoon. A trailing boundary from the surface low will see afternoon shower and thunderstorm redevelopment along it with afternoon diurnal heating, however this is expected to sink south of the area and not impact Iowa.

LONG TERM /MONDAY THROUGH FRIDAY/

Issued at 230 PM CDT Sat May 2 2026

The final push of warm air advection will send temperatures into the mid to upper 70s. A long wave trough sinking into the Canada-US border will push a cold front across Iowa later Monday and Tuesday. Showers and thunderstorms will develop along the boundary through the late afternoon and evening. Farther south a surface low will undergo lee cyclogenesis and eject east across Kansas and Missouri. Moisture transport increases ahead of this low, however with the cold front sinking south and the surface low moving across Kansas and Missouri, this moisture is unlikely to make it far north into Iowa. This will limit better instability in the state along with better forcing expected nearer the surface low. So while showers and a few thunderstorms are possible along the cold front, any strong/severe threat is higher south of the state.

Tuesday will be much cooler behind the cold front with afternoon highs in the 50s. Cooler temperatures last much of the week with the upper level trough dominating the upper air pattern locally. By Wednesday into Thursday the trough axis finally lifts to the east, allowing warm air advection back into the area. Better forcing will be farther south near the base of the trough, however some shower and thunderstorm activity is possible into Iowa. Warmer air in the 70s returns back to the area by late next week.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1232 PM CDT Sat May 2 2026

A weak system is moving through this evening and overnight. As this system moves through, light showers are possible at ALO but dry air near the surface decreases confidence in anything reaching the ground. For the same reason, mentions of showers at MCW and OTM were not included with lower confidence in anything reaching the ground at these sites. As this system moves through, winds will shift to being from the west to becoming southerly/southwesterly overnight. Along with this wind shift, Low Level Wind Shear is possible at FOD, DSM, and OTM. Around sunrise and through the afternoon tomorrow, winds will shift again to being from the south to being from the northwest. Similarly, after sunrise, Low Level Wind Shear will diminish across the area.

DMX WATCHES/WARNINGS/ADVISORIES

None.