1843: A spectacular cloudburst near Philadelphia turned the small creeks and streams entering the Delaware River into raging torrents. According to David Ludlum, as much as sixteen inches of rain fell in just three hours. Flooding destroyed thirty-two county bridges and caused nineteen deaths. It is believed that several small tornadoes accompanied the torrential rains, one of which upset and sank more than thirty barges on the Schuylkill River.
1875: Several tornadoes moved across northern and central Illinois. One of the stronger tornadoes touched down in Warren and Knox County where it destroyed 25 homes and killed two people. Another in a series of tornadoes touched down near Knoxville and moved east into northern Peoria County. This estimated F4 tornado injured 40 people and was described by eyewitnesses as looking like a “monstrous haystack.”
1980: Hurricane Allen was one of the most intense hurricanes ever observed in the Atlantic. On this date, the hurricane reached Category 5 status for the first of three times during its long path across the Atlantic as reconnaissance aircraft measured 911 millibars (26.90 inches of mercury) pressure in the eastern Caribbean while south of Puerto Rico.
— NWS Seattle (@NWSSeattle) August 6, 2017