Multiple small but potent storms have popped up in eastern KELOLAND today. Areas near Madison and Salem saw storms with quarter sized hail reports just south of Salem. This thunderstorm only lasted about an hour during midday, but as soon as it ended, another thunderstorm generated just east of Huron, reaching its peak just before 1 PM. Other than that, some spotty areas of showers appeared here and there with temperatures in the 80s for most areas. It is still possible for daytime thunderstorms to develop.
Storms redevelop for most areas tonight, continuing our trend of overnight thunderstorms. A strong line of storms is expected to move across the entire state tonight from west to east. Most of of KELOLAND is rated a slight risk of severe weather by the Storm Prediction Center. Sioux Falls area is on the very edge and may not see severe weather until early Thursday morning. Heavy rainfall will be possible tonight and early tomorrow, especially along and north of Highway 14, where rainfall totals around an inch and a half are indicated. Temperatures tonight will remain in the mid 60s, and it will be somewhat humid.
Possible light rainfall throughout the day on the 4th, with thunderstorms still in the forecast for the late afternoon and evening hours. There will be a frontal boundary in southeast South Dakota during the early parts of the day tomorrow, with temperatures southeast of it getting into the upper 80s, creating warm and steamy conditions. Once that passes, the Sioux Falls area will join the rest of the state with thunderstorms developing during the evening hours. Again there will be a risk of strong storm – but also a somewhat higher potential for areas of heavy rainfall with those storms.
Friday looks cloudy and rainy – and forecast models continue to stress the potential for heavy rainfall, with amounts over an inch. Temperatures will also be cooling down, with highs in the upper 70s to low 80s.
As far as the weekend, we’ll keep a chance of rain in the forecast East River on Saturday morning before the rain moves out from west to east. With decreasing clouds it will also be a little cooler than normal, with highs in the upper 70s to low 80s. Sunday looks like the nicer day of the weekend, with partly cloudy skies and highs I the low 80s East River to the mid 80s in the west.
We will warm back up near or above normal Monday into Tuesday, but the warmer air comes with another round of thunderstorms both days. Then another batch of colder air drops down from the north, with below average temperatures the second half of next week.