May was the hottest month in recorded US history. According to the National Oceanic and Atmospheric Administration (NOAA) land and ocean temperatures in May 2014 were the hottest combined average temperatures every recorded for the month.
Four of the five warmest months of May on record have occurred in the last five years. Global sea level temperatures tied the highest departure from average for any month on record.
May 2014 marked the 39th consecutive May and 351st consecutive month (more than 29 years) with a global temperature above the 20th century average. The last below-average global temperature for May took place in 1976.