textproduct: Des Moines

KEY MESSAGES

- Dry conditions continue today and Wednesday, with breezy winds possible north and west on Wednesday.

- Rain chances increase late Wednesday night into Thursday, beginning over northwest Iowa then slowly progressing south and east through Thursday. A few severe storms are possible Thursday afternoon and evening. - Shower and storm chances continue into Friday, with more chances for strong to severe storms with heavy rain through Friday evening.

SHORT TERM /THROUGH THURSDAY/

Issued at 247 PM CDT Tue Jun 2 2026

The surface high over the Great Lakes region has full control over the weather in Iowa today, as clear and dry conditions prevail. Soundings over the state echo this, showing over a 15C T/Td spread through the entire layer from the surface up to 350 mb. With the dry profiles, the boundary layer has mixed out well today allowing for some breezier winds east southeast winds to develop. This is especially true over northwest Iowa where surface pressure gradients are slightly stronger. Dry conditions continue overnight, with any rain chances expected to remain well to the west of the area through Wednesday morning.

Our high pressure to the east will maintain it's influence in the state during the day Wednesday, keeping most of the area dry. However, the high will be progressing south and eastward through the day, flipping surface flow to southerly and allowing more moisture to work into the state from the south and west. With these increasing surface temperatures and dewpoints, we'll begin to see the more unstable airmass to our west also work it's way into western Iowa through Wednesday. This may allow for an isolated shower/thunderstorm in the far western/southwestern reaches of the area, but coverage should be minimal with the dry air still holding over most of the area. Instability could be sufficient for a few stronger updrafts and dry sub-cloud air could enhance downdraft winds, but shear will be weak and storms likely disorganized. Therefore, any severe threat will be low on Wednesday. Aside from low (less than 15%) precipitation chances Wednesday, tightening pressure gradients from low pressure encroaching from the west will allow for breezy conditions with wind gusts of 20 to 25 kts.

By Wednesday night, the moisture axis will have finally pivoted into western Iowa, bringing better chances for showers and thunderstorms overnight and mainly into Thursday morning. This activity will originate in Nebraska and South Dakota along a boundary, but eventually evolves into more scattered precipitation being fueled by the weak low level jet and theta-e advection now passing through the state. This moisture advection will keep scattered showers and storms over the northwest portions of the area through the day on Thursday, progressively tracking farther south and east into the evening and overnight hours. It's worth noting that precipitation chances are in place all day Thursday, but rain will be scattered and likely not a complete washout. Instability will be increasing during the day on Thursday as well, which could open up the potential for a few stronger storms in the afternoon. This of course will depend on the degree of destabilization, but 1000+ J/kg of MUCAPE could certainly develop in areas that are able to clear out during the day. This could allow for a few strong to severe storms on Thursday, although the marginal deep layer shear around 25 to 35 kts may somewhat limit storm organization. The storm prediction center has placed a marginal risk (level 1 of 5) for severe weather over the northwestern half of Iowa for Thursday. PWATs on Thursday will also be in the 1.5 to 1.6 range, which is near the 90th percentile of PWAT climatology for early June. Therefore, showers or storms could produce some efficient rainfall. This rainfall will be much needed given our recent dry spell, but prolonged rain in a short time could still lead to localized ponding impacts, mainly in urban areas.

LONG TERM /THURSDAY NIGHT THROUGH MONDAY/

Issued at 247 PM CDT Tue Jun 2 2026

The 500 mb ridge responsible for our dry mid-week conditions will be suppressed south and eastward by Thursday night, transitioning the upper level pattern over Iowa to more of a southwest to zonal flow pattern. This pattern will have keep persistent moisture advection up into the state Thursday night into Friday, leading to additional scattered shower and storm chances overnight. By Friday afternoon and evening, a shortwave will drop southeastward into Iowa, bringing additional synoptic forcing and a cool front. Showers and storms will develop along this boundary within a moist and unstable environment. Wind shear on Friday will once again be on the lower end, but with the boundary passage and upper level support, certainly can't rule out more strong to severe storms late Friday into the evening. Likewise, a high PWAT environment (1.6 to 1.7") will still be in place ahead of this boundary, resulting in another round of efficient and potentially widespread rainfall. Again, our dry spell should allow us to handle most of this, but rain falling in similar areas over multiple days could lead to some localized hydro concerns into the weekend.

Through Saturday and Sunday, a brief period of upper level ridging will bring warmer and somewhat drier conditions over Iowa, although shower and storm chances could still linger over the southern portions of the area. This reprieve looks fairly brief, as Sunday night into the beginning of next week could see another wet pattern develop.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1204 PM CDT Tue Jun 2 2026

VFR conditions prevail through the TAF period. Winds will be light to occasionally breezy out of the east southeast at 10 to 15 kts, gusting to around 18 to 20 kts at times. Winds and gusts diminish overnight, then pick up out of the south again on Wednesday.

DMX WATCHES/WARNINGS/ADVISORIES

None.