Monday, May 1, 2017
Small Hail with a Few of the Stronger Showers Monday Afternoon
It wasn't overly warm at the surface, but definitely a lot warmer than what it was roughly 10,000ft up into the atmosphere. Temperatures there fell between -11 and -13 degrees! Pretty cold for the start of May. As low pressure moved into southern Wisconsin surrounding air was forced upwards, due to a decrease in pressure. As the air was pulled up, it quickly cooled causing just enough instability in the atmosphere to form those bulky looking cumulus clouds we had earlier today and eventually leading to the bouts of heavy rainfall during the afternoon. Since the air didn't have far to travel aloft before running into an air mass where temperatures were below freezing, the liquid droplets were quick to freeze into tiny hail stones. The showers that developed were not strong enough to maintain the now heavier frozen droplets, or hail, in the atmosphere causing them to fall with the stronger showers.
There will still be a few showers from time to time Monday night, but as the low pulls even further away from the western Great Lakes the rain will become less and less. Cloud cover does stick around, but at least our skies will begin to dry out.