Average July Overnight Low Temps In Lower 48 States Highest In Weather Records For Month
Unseasonably hot July days turned into uncomfortably warm nights over large areas of the Lower 48 states, as average overnight temperatures hit their highest level in recorded history, according to the National Oceanic and Atmospheric Administration.
Although it was the nation’s third-hottest July on record taking into account daytime temperatures, the nighttime warmth was unsurpassed — not just for July, but any month in 128 years of record-keeping, as first reported by meteorologist Bob Henson at Yale Climate Connections.
July 2022 recorded an average low temperature of 63.57 degrees in the contiguous United States, the warmest since official record-keeping began in 1880. July 2012 — with an average minimum temperature of 63.55 degrees — was the previous record holder.
A trend toward warmer nights is one of the leading indicators of human-caused climate change, reflecting both the buildup of greenhouse gases in the atmosphere and urbanization. According to Climate Central, a nonprofit science communications group, summer minimum temperatures have warmed nearly twice as fast as daytime highs. Averaged across the Lower 48 states, summer nights have warmed 2.5 degrees since 1970.
The cities with the most pronounced nighttime warming since 1970, according to Climate Central, are Reno, Nev. (17.3-degree increase); Las Vegas (9.5-degree increase); El Paso (8.1-degree increase); Salt Lake City (7.3-degree increase); and Boise, Idaho (6.9-degree increase).
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https://www.washingtonpost.com/climate-environment/2022/08/10/hottest-us-nights-july-climate/