Is spring the new summer? So it felt like it across the U.S. this year, as temperatures topped 57 degrees during the months of March, April, and May, 5 degrees above average. The average beat out the previous record by a full 2 degrees. The National Oceanic and Atmospheric Administration reported that the month of May was the second warmest since records began in 1895, with an average temperature of 64.3, behind only that of 1934. Collectively, the first five months of 2012 have been the hottest start to any year in U.S. history, while the 12-month period that began last June is also the hottest on record for the country.