May through July was the warmest such period on record
The heat was hard to beat around the U.S. last month, making it the 11th warmest July on record. And the sweltering temperatures the last three months brought the warmest May through July on record, according to scientists at NOAA’s National Centers for Environmental Information (NCEI).

Death Valley National Park set a new world record in July 2018: It was the hottest place during hottest month on record. Temperatures reached 127 degrees F for four days in a row (as shown in this photo of a temperature sign in front of the park's visitor center), and the park experienced an average monthly temperature of 108 degrees for July. Learn more at https://www.nps.gov/deva. (Image credit: Death Valley National Park/NPS)