Thunderstorms have developed late Tuesday afternoon, moving across much of southern Wisconsin and entering into far northwest Illinois. There have been a few severe thunderstorm warnings in Wisconsin and Iowa, but no warnings locally just yet. However, storm coverage is expected to increase over the next hour or two for northern Illinois as storms to the north and west continue to slowly progress east. Additionally, outflow boundaries from surrounding storms could help produce a few more isolated thunderstorms through 8pm/9pm.
There is a marginal risk for strong/severe storms over portions of Wisconsin and Illinois, with wind and hail being the primary concerns. Some of the storms that have turned severe have produce wind damage in Wisconsin and Iowa. Heavy downpours and localized flooding may occur given the slow movement of thunderstorms. Skies will turn partly cloudy during the overnight with lows in the low 70s.