July 2012 hottest month in US's history

The average temperature in July was 25.3 degrees Celsius more than the average 20th-century temperature thereby breaking the July 1936 record of 25.2 degrees, the National Oceanic and Atmospheric Administration said.

Virginia had its warmest July on record, with the average temperature four degrees above the norm.

Climatologists at the agency noted that by the end of the month, about 63 per cent of the nation was experiencing drought conditions, which was an add on to the high temperatures.

"July was a pretty interesting month because there were two different things at play," a climatologist at the agency's National Climatic Data Center Jake Crouch was quoted as saying by the 'New York Times'.

"We saw very warm daytime temperatures over a large part of the country related to the ongoing drought, just as in 1936. When soils are dry, especially during the summer, it drives the daytime temperatures up. But this is a very local effect," Crouch said.

"The hotter days increase the amount of moisture the lower atmosphere can hold, and this means it doesn't cool off as much at night anymore," he added.