At a Glance: May 2018 was the hottest in 124 years of May records across the Lower 48. Eight states broke warmth records and no state was colder than average. Two states had their wettest Mays. May 2018 was the hottest of any May in 124 years of recording keeping for the continental United States, eclipsing the extreme heat of that month in the 1930s during the Dust Bowl era. The average temperature for the Lower 48 states last month was 65.41 degrees Fahrenheit, 5.21 degrees Fahrenheit above the 1901-2000 average, according to the state of the climate report released...