NOAA - 2016 6th-Warmest US Summer; Hottest Ever For RI, CA, CT; US Night Temps Hottest Ever
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The summer (June-August) temperature for the contiguous U.S. was 73.5°F, or 2.1°F above the 20th century average, tying 2006 as the fifth warmest in the 122-year period of record. Above-average temperatures spanned the nation during summer. Every state across the contiguous U.S. had a statewide temperature that was above average. Twenty-nine states across the West and in the East were much warmer than average.
California, Connecticut and Rhode Island each had their warmest summer on record. The California statewide average temperature was 75.5°F, 3.3°F above average, the Connecticut statewide average temperature was 71.9°F, 3.7°F above average, and the Rhode Island statewide average temperature was 71.6°F, 3.7°F above average.
Alaska observed its second warmest summer in its 92-year record at 53.6°F, 3.0°F above average. Only the summer of 2004 was warmer with a statewide temperature value of 55.9°F. Several locations across the state were record warm including Anchorage, Kenai, King Salmon and Yakutat.
The contiguous U.S. average maximum (daytime) temperature during summer was 86.2°F, 1.8°F above the 20th century average, the 10th warmest on record. Above-average maximum temperatures were observed for both the eastern and western U.S. with near-average maximum temperatures across the Great Plains and parts of the Midwest. California and Rhode Island each had a record warm summer maximum temperature at 3.3°F and 4.2°F above average, respectively.
The contiguous U.S. average minimum (nighttime) temperature during summer was 60.8°F, 2.4°F above the 20th century average, the warmest on record. This surpassed the previous record of 60.7°F in 2010. Every state across the Lower 48 had an above-average summer minimum temperature with 36 states much warmer than average. Ohio had a record warm summer minimum temperature at 63.2°F, 3.9°F, surpassing the previous record of 63.1°F in 2010.
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https://www.ncdc.noaa.gov/sotc/national/201608
