Widespread frost likely tonight
The general rule of thumb for planting in southeast Wisconsin is to wait until after Mother’s Day. Hopefully you followed that rule and held off on planting because a widespread frost is expected tonight! Mostly clear skies and light winds will allow temps to tank into the low to mid 30s overnight.
Folks in Fond du Lac and Sheboygan counties have the best chance at temps falling below freezing, so a Freeze Warning has been issued for those counties. The rest of southeast Wisconsin is under a Frost Advisory that runs from Midnight through 8am Saturday. Cover up any outdoor plants or bring them inside if possible!
Temps will be too warm for frost Saturday night, but there’s another chance temps dip back into frost territory away from the lake Sunday and Monday nights. Frost chances both of those nights will depend on cloud cover.
Increasing clouds and a chance for showers will prevent frost on Saturday evening, however how north the showers make it is still in question.
A system will track across Illinois Saturday night into Sunday morning, but there’s uncertainty whether or not this system will track across central or southern Illinois. If it tracks across central Illinois, showers would become likely Saturday night into Sunday morning. A more southerly track would keep the rain in northern Illinois.
Hopefully this system will track to the south, but keep the umbrella handy for Mother's Day morning just in case. Download the CBS 58 Ready Weather App to see if there's any warmer weather on the horizon.