Violent thunderstorms menaced Florida, and two tornadoes touched down along Florida's Gulf Coast. Severe weather warnings were issued in east-central Florida as the band of thunderstorms swept inland, bringing hail, heavy rain, lightning and 25-m.p.h. wind gusts. In Wimauma, about 15 miles south of Tampa, a tornado toppled a metal shed in a strawberry field, killing a 41-year-old man who was running for cover from the rain, authorities said. A second tornado struck near Inverness, Fla., but no injuries were reported.