textproduct: Des Moines

KEY MESSAGES

- Periods or rain with a few embedded thunderstorms through early Sunday. Total rainfall amounts of 1 to 2 inches are possible over parts of central and southwest Iowa.

- Another strong storm system expected Tuesday and Tuesday night. Thunderstorms with heavy rainfall are possible.

- Highs generally in the 60s and low 70s.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 251 PM CDT Thu Sep 24 2026

High pressure ridging remains over eastern Iowa this afternoon while return flow has arrived over western Iowa. A stratus layer of clouds is occupying parts of eastern Iowa despite the high pressure ridging. Rain has increased over western and parts of north central Iowa this afternoon in response to the moisture return. Cloud bases are beginning to respond with cigs near 1 kft over far northwest as the top-down saturation occurs. The light rain will expand into central Iowa tonight though with gradual diminishing returns as it encounters dryer air to the east. A short wave lifting through the region tonight into tomorrow morning will result in a more widespread area of precipitation moving into southwest to central Iowa. Some convective elements are possible with this precipitation but weak instability and weak mid-level lapse rates will keep lightning to a minimum. Precipitation amounts of one half to one inch could occur over parts of the southwest forecast area by early Friday afternoon. The precipitation will diminish in the afternoon and evening before the next round arrives.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 251 PM CDT Thu Sep 24 2026

Another short wave will arrive Friday night into Saturday as the moisture plume continues to slowly track eastward resulting in another round of widespread precipitation. More instability is possible over western Iowa on Saturday afternoon which could result in more convective activity but again, the threat for strong storms is low. Dryer air will arrive from west to east late Saturday night into Sunday though mostly cloudy skies are expected to persist. Monday will be mostly dry and slightly warmer with highs in the 60s to near 70. Another strong short wave will arrive Tuesday and Tuesday night. PWAT values will approach 2 inches and conditions will be favorable for rainfall amounts of 1-2 inches. Note, Des Moines is currently a little over 2 inches from the September record for precipitation. This will be approached with the system this weekend and the one early to mid next week.

For Wed into the end of the week, models are taking turns trying to ingest the Pacific Hurricane Palo into southwest flow as a strong upper level low approaches the Four Corners region. There remains a lot of uncertainty here regarding this ingestion and the overall evolution of the upper level low but a slower progression of everything may lead to more wet weather for Iowa.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 650 PM CDT Thu Sep 24 2026

Light rain continues to slowly spread across the state this evening, with most terminals seeing rain outside of KOTM and KALO. While rain continues into the night, will see a gradual decrease in precip trends over the northern terminals, and an increase at KDSM and KOTM after 06z and especially beyond 12z as a stronger wave brings higher chances for rain. Ceilings will continue to lower overnight and through the morning, with MVFR common and IFR also expected at times. Winds remain light out of the southeast, then increase towards the latter half of the period as occasional gusts up to 15-20 knots are then possible.

DMX WATCHES/WARNINGS/ADVISORIES

None.