These are the ten hottest weather temperature days in the history of Washington D.C. dating back to 1878. On Friday, July 22, 2011, the temperature in Washington D.C. reached 105 degrees. That is tied for the third hottest temperature ever recorded in Washington D.C., and breaks the record for the hottest July 22nd ever (old record was 103).
It can get pretty hot in the summer in the nation's capital. Since 1878, there have only been four days in the month of July (11th, 12th, 29th and 30th) when the temperature did not reach 100 degrees or more during at least one summer.
I've been to Washington D.C. a number of times in the summer to visit the great sights there, and I cannot remember once being there when it was not pretty hot. I live in New Jersey, about equal distance from Philadelphia and New York City, and without any doubt Washington D.C. gets much hotter in the summer than either Philadelphia or New York does.
10 Hottest Temperature Days in Washington D.C. History
T-1. July 20, 1930 - 106 degrees
T-1. August 6, 1918 - 106 degrees
T-3. August 17, 1997 - 105 degrees
T-3. July 10, 1936 - 105 degrees
T-3. July 22, 2011 - 105 degrees
T-5. June 29, 2012 - 104 degrees
T-5. July 16, 1988 - 104 degrees
T.5 July 9, 1936 - 104 degrees
T-5. July 21, 1926 - 104 degrees
T-5. August 7, 1918 - 104 degrees
T-5. September 7, 1881 - 104 degrees
Comparing the hottest days in Washington D.C. to the hottest days in Philadelphia and New York City.
Number of Days the Temperature Did Not Reach 100 Degrees in July
Washington D.C. - 4 dates (11th, 12th, 29th and 30th)
Philadelphia - 9 dates (12th, 13th, 18th, 20th, 23rd, 24th, 25th, 29th and 30th)
New York City - 11 dates (11th, 12th, 16th, 23rd through 30th)
For more see 100 Degree Weather Temperature Days in New York City