With the extra heat and humidity from the day, there is still the possibility for some storms to pop up this evening in the eastern half of the state. These will be random in nature and because these are diurnally driven, should they develop, they will fade out relatively quickly once the sun goes down. Lows tonight cooling to the low 70s with mostly clear skies.
Monday, the last day of this heat wave, areas in central KELOLAND will reach the 100 degree mark again. Everywhere else will top out in the mid to upper 90s. Because of the strong heat, the National Weather Service has issued a heat advisory for eastern KELOLAND that will go into effect Monday at 11AM CDT and is set to expire at 9PM CDT Monday evening. They are expecting heat index values to range from 100 to 105.
Monday late afternoon/evening, central and eastern South Dakota have a chance for some thunderstorms. The southerly winds all weekend bringing in more moisture on top of the extra heat energy from the day, some of these storms could be severe with high winds and large hail. The strongest weather looks to be mostly in the northeast portions of the state and in central Minnesota.
These look to fade out by Tuesday morning, dry conditions for the rest of the week until Thursday evening and Friday. Highs cooler in the low 80s to around 90 lasting throughout the week.