textproduct: Des Moines

KEY MESSAGES

- Precipitation ending this afternoon then a mostly dry period expected through at least Monday afternoon. Very warm on Monday with highs in the 70s and 80s.

- Periods with storms and severe weather possible Tuesday and Wednesday.

- Another period of storms and potentially severe weather arrives on Friday followed by a cooler weekend.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 243 PM CDT Sun Apr 12 2026

The active forecast period will persist through much of this upcoming week. A broad area of rain is lifting northeast across central and southeast Iowa this afternoon. Currently the activity in Iowa is mostly devoid of any lightning and that can be contributed by the moist adiabatic lapse rates while this moisture plume with pwats near 1.5 inches moves across the area. Strong warm advection in the 900-800 mb layer tonight will result in a stout elevated mixed layer (EML) surface capping inversion. That EML will persist through much of Monday and perhaps into a part of Tuesday. Moisture will be trapped beneath this inversion though at this time, it appears the trapped moisture will translate to a stratus layer as opposed to ground fog. Will continue to monitor as some high resolution guidance has the warm front settling back into far northern Iowa overnight where lighter wind and moisture pooling along the cooler side of the boundary could occur.

Precipitation chances will diminish as the main precipitation shield passes to the northeast as the EML arrives. At this time, expect the EML to hold on Monday as mentioned above and that the current slight risk for severe weather over northern Iowa may need to be shifted further north into Minnesota where the warm front will be located. The one potential caveat for this scenario is a surface boundary moving into northwest Iowa Monday evening/night. Most model guidance suggests this is a shallow boundary intrusion with the EML holding aloft and the developing low level jet remaining focused into Minnesota.

LONG TERM /TUESDAY THROUGH SATURDAY/

Issued at 243 PM CDT Sun Apr 12 2026

The greater severe weather chances appear to arrive on Tuesday and Wednesday. The boundary will be meandering over Iowa during this period with the EML gradually eroding. Tuesday severe weather potential does feature increasing instability that will be favorable for updraft acceleration and hail production along with a damaging wind potential. There is a lower chance for tornadoes though there may be a window in vicinity of the boundary. The upper level short wave and going spring severe weather climatology with an upper low lifting northeast into central/northeast Nebraska by the afternoon. Pattern recognition does suggest this setup often brings severe weather to Iowa including tornadoes along the surface warm front. Note, the NAM is much weaker and faster with this upper wave and thus is much more limited on severe weather potential on Wednesday. Other solutions appear to have a better handle on a potential closed upper low situation with a surface low that does include some deepening into the afternoon.

Thursday will be a quieter day but remaining warm. Another strong system and cold front will arrive on Friday and will bring the next chance for thunderstorms and potential severe weather. Cooler but still near seasonal weather will follow for the weekend.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1233 PM CDT Sun Apr 12 2026

A mix of VFR and MVFR cigs this afternoon as a layer of stratocumulus has developed under the upper level clouds that are passing across Iowa. In addition, a broad area of precipitation is lifting northeast from southern Iowa and will mainly impact the southeast half of the state this afternoon, including KDSM/KOTM/KALO. Additional stratus may develop overnight just below a steepening inversion. At this time, stratus formation is favored over fog formation. Therefore, while there may be some areas with vsby reductions, the stratus should limit the fog impacts. The wind will be gusty from the southwest today then will gradually diminish late this afternoon and early evening.

DMX WATCHES/WARNINGS/ADVISORIES

None.