textproduct: Sioux Falls

KEY MESSAGES

- The better chance of thunderstorms this afternoon has shifted east of the forecast area. However, there is a low confidence risk for isolated storms near the Highway 71 corridor in the mid afternoon.

- By late tonight/early Thursday morning, a few stronger storms may develop from around Sioux City into portions of northwest Iowa. Isolated wind gusts to 60 mph and hail up to ping pong ball size would be the main threats.

- Less humid air begins to filter into the region today, with highs in the 70s to lower 80s Thursday, and again this weekend into early next week.

- Saturday will see a chance of thunderstorms over mainly northwest Iowa. While a lower probability scenario (~20%), a few stronger storms are possible.

DISCUSSION

Issued at 340 AM CDT Wed Jun 10 2026

Severe storms have exited to the northeast and residual wake low winds likewise subsided across the forecast area prior to 2 AM. Lingering showers and a few embedded thunderstorms will continue through daybreak then gradually diminish through mid-morning. The well-advertised cold front will push east across the forecast area today, with best consensus still showing the front reaching Highway 71 by around 3 pm. This leaves a very narrow window of opportunity for development in our far eastern counties this afternoon, though greater consensus points to development just east of our area after 21Z. That said, may carry a low pop in our far east to account for a slightly slower 3km NAM solution which shows spotty development near Highway 71 in the mid-late afternoon.

More concerning area for potential stronger storms will come late tonight into early Thursday in parts details are still uncertainof northwest Iowa as a strong wave slides northeast along a low level warm front. Greater chances for organized severe storms, including early morning supercells transitioning into an MCS, appears focused just to our south. However, the low-level boundary is close enough to heighten awareness for a possible stronger storm in areas from around Sioux City into portions of northwest Iowa during the morning commute time (~5 am to 9 am). At this time, the primary threat looks to be hail up to ping pong ball size with isolated gusts to around 60 mph possible.

A compact upper trough swings across the eastern Dakotas into Minnesota Thursday afternoon, well behind the departing cold front. While severe storms are not anticipated, weak shallow instability beneath the upper trough could support spotty showers or storms developing. The RAP indicates a north-south zone of Enhanced Stretching Potential beneath the trough which could indicate a weak funnel cloud potential with developing updrafts.

A brief warm-up Friday before another cool front pushes south on Saturday. If the front is slower to move through, southeast parts of the forecast area could be on the northern fringe of a severe weather risk, but this is a lower probability scenario with greater risks located south of the area. Those with outdoor plans on Saturday will want to monitor the latest forecasts.

The cooler air with highs mostly in the 70s looks to stick around Sunday through Tuesday next week, with a wave sliding through the northwest flow bringing a low chance of showers or storms on Monday.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1234 PM CDT Wed Jun 10 2026

Mostly clear skies will prevail for the first half of this period. Behind the cold front winds will become northwesterly and breezy. Afternoon gusts of of 25-30 kts are expected with the highest gusts over central South Dakota. Winds will decrease after sunset becoming light and variable.

Shortly before midnight tonight clouds begin to build in ahead an area of showers and thunderstorms. For areas north of Highway 81, severe weather is not anticipated. However, a few storms may produce brief heavy downpours. For areas to the south of Highway 81, and especially to the east of Highway 60, chances for strong to severe thunderstorms return between roughly 10-15Z Thursday morning. Storms may be capable of producing large hail to the size of a ping-pong ball and wind gusts up to 60 kts. Showers and storms continue through the end of the period.

FSD WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None. IA...None. NE...None.