Some scattered light showers have developed across central and eastern SD this morning, but most amounts have been light at just a few hundredths of an inch. Highs today will be cooler in most areas in the mid to upper 70s.
An active weather pattern will begin starting tonight in western KELOLAND where t-storm chances will be on the increase overnight. Those chances of rain will spread east tomorrow, with a 30% chance of PM rain in Sioux Falls. The best chances of rain east of James Valley will be tomorrow evening, but some rain may linger into Friday AM. This first wave may have some strong storms in northeast Nebraska and some downpours could be over .50”. We’ll have more that later today.
On Friday, we will be dealing with the leftover morning rain in the east and some chance at new t-storms in central SD where the data is hinting at the best forcing. I wouldn’t rule out a severe storm, but this t-storm chance looks more disorganized, especially for Sioux Falls.
Saturday is another challenging day of forecasting. The morning could feature some left over rain from anything that does develop Friday night. I think that looks limited, perhaps more in the northeast. The bigger show will be Saturday night. A line of strong to severe storm could fire from north-central SD down the Missouri River Valley at that time and then move east. Large hail and damaging winds could be possible. Remember, Saturday will be warm and humid ahead of the thunderstorm chances.
Once that departs, more rain is likely on Sunday. Depending on where the low tracks, parts of the southeast could get another round of severe weather, but the scenario to the west and north will be widespread soaking rainfall. Rain will likely continue into Monday and even perhaps Tuesday. This may very well be a big rain producing system with widespread 1-3+” rainfall amounts in KELOLAND through the 5 day period starting tomorrow. Stay tuned.