May 2011: Globe Warms, But U.S. Cools

Last month also brought heavy precipitation to parts of the U.S. The only part of this home in Vicksburg Mississippi above water on May 13, 2011 was the roof. CREDIT: Howard Greenblatt | FEMA.gov View full size image

Globally, last month continued the warming trend of recent years, according to a monthly report by the National Oceanic and Atmospheric Administration.

May 2011 was the 315th consecutive month to have a global temperature above average. The last time global temperatures dropped below the 20th-century average was in February 1985.

Of course, that doesn't mean all Earthlings felt the heat. Australia had one of its coolest Mays on record, while nearby New Zealand had its warmest May on record, according to NOAA. Arctic sea ice, which has been in decline for decades, was below average for the 120th consecutive month.

Parts of Argentina reported record lows in precipitation since 1961, while this was the wettest May on record for much of the northern Plains and northern Rockies in the United States, leading to flooding.

May 2011 saw dramatic shifts in regional temperatures in the U.S., and the average temperature, 60 degrees Fahrenheit (16 degrees Celsius), fell just below the 20th-century average by 1.0 degrees F (0.6 degrees C). [Strange Weather's Loose Link to Global Warming]

NOAA's weather data extends back to 1880.

You can follow LiveScience writer Wynne Parry on Twitter @Wynne_Parry. Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on Facebook.