Powerful thunderstorms erupt Thursday prompting tornado warnings ; 2" swamps Joliet in 45 minutes; severe t-storm watch covers Chicago metro area until 11 p.m. Thursday.

This was the ominous scene in Round Lake Beach in Lake County this afternoon as downpour-generating t-storms erupted as photographed by Pam Sobieski. Radar cloud top scans indicated cumulonimbus clouds have grown to heights of 50,000 ft. this afternoon. To the south, tornado warnings were issued in response to numerous funnel reports—among them in Orland Park, Joliet, Shorewood and Minooka—and Doppler indicated tornado circulation signatures. Rain was torrential under the heaviest cells totaling 1.88" in 45 minutes in Joliet. Doppler precipitation estimates indicate several corridors of 1-2" of rainfall. But storms weren't universal. Estimates of areal rain coverage suggests 20-30% of the Chicago metro area has been visited by the storms. A severe t-storm
watch covers the entire area until 11 p.m.

PHOTO COURTESY: Pam Sobieski