According to records going all the way back to 1895.
Scientists with the federal National Oceanic and Atmospheric Administration said Wednesday (August 8th) that July was the hottest month ever recorded in the mainland U.S. in records going back to 1895, breaking a record set during the Dust Bowl of the 1930s. The average temperature last month was 77.6 degrees, breaking the old record from July 1936 by 0.2 degrees, what NOAA scientist Jake Crouch called "a pretty significant increase." Three of the nation's five hottest months on record were in recent years, July 2011 and July 2006. There other two months in the top five were from the Dust Bowl years, July 1936 and July 1934. The latest record news comes after the first seven months of 2012 were the hottest on record for the nation, and August 2011 through July of this year registered as the hottest 12-month period on record. NOAA also has a Climate Extreme Index, which tracks several indicators of unusually high and low temperatures, severe drought, downpours and tropical storms and hurricanes, and is calculated as a percentage, which mostly reflects how much of the country experiences extremes. In July, the index was 37 percent, beating the old record from last July, and nearly doubling the average of 20 percent.