Image (click to enlarge): U.S. daily high temperatures for October 2, 2011, from Unisys
October 3, Midnight Update: The National Weather Service reported today that Salisbury, Maryland also set a new record low daily maximum temperature for October 2 (Sunday). The high of 55° beat the old record of 56° in 1940. Salisbury climate records date back to 1900.
October 3, 5:30 PM Update: A late surge of sunshine could change the final result, but today's high temperature so far of 53° at Washington National is tied with the record daily low maximum from 1974. The 51° at Dulles has already missed the record of 49°, also from 1974. Baltimore has also missed the record with 56°, vs. the record of 52°, again from the same year.
October 3, 12 PM Update: The preliminary daily high temperatures are confirmed.
Unless temperatures inexplicably jump several degrees in the next hour or so, daily record low maximum temperatures for October 2 will be set or tied at all 3 major reporting locations in the Washington/Baltimore area. The high of 58° at Richmond, however, is 4° above the daily record low maximum. The high of 56° at Philadelphia has also missed its record, which is 53° in 1899. Today's preliminary highs and the previous records for the date in parentheses from National Weather Service climate data:
Washington National 52 @ 1253 PM (52, 1939)
Washington Dulles 50 @ 1226 PM (54, 1974)
Baltimore BWI 51 @ 1120 AM (53, 1939)