Wednesday afternoon weather update

(1:53:36 PM) nwsbot: Local Storm Report by NWS MKX: 4 N Lake Geneva [Walworth Co, WI] trained spotter reports HAIL of pea size (E0.25 INCH) at 01:52 PM CDT -- heavy rains




I'm currently monitoring a line of storms crossing the Jo Daviess/Stephenson County line this afternoon.  This line is moving to the east/northeast around 45-50 mph and may move just to the north and west of the Rockford Metro, but impact places like Monroe, Freeport, Winslow, Orangeville and Cedarville between now and the next 20 minutes.  At this time there are no warnings and due to the stable nature of the atmosphere and cooler air the main threats from the storms would be small hail (pea to nickel sized), gusty winds and heavy rainfall.

Temperatures as of Noon remain in the 40s here but 60s and 70s just south of Sterling!  The warm/stationary front has remained south of the Stateline through the morning and will likely stay to the south headed into the afternoon.  This should keep the majority of any severe weather south while elevated thunderstorms are what we'll be watching through the afternoon.  Warm, moist air moves up over top the cooler and more stable air at the surface causing thunderstorms to become elevated rather than surface based.  The main threat with elevated thunderstorms is hail because the freezing level in the atmosphere (32° or cooler) is lower making it easy for hail to form.  This is likely what we'll see with the line of storms that are currently moving through Stephenson County.