Last month was the second warmest July on record, and so far 2010 remains on track to be the hottest year.
Worldwide, the average temperature in July was 61.6 degrees Fahrenheit (16.5 Celsius), the National Climatic Data Center reported Friday. Only July 1998 was hotter since recordkeeping began more than a century ago.
And the January-July period was the warmest first seven months of any year on record, averaging 58.1 F (14.5 C). In second place was January-July of 1998.
The report comes after a month of worldwide extremes including floods, fires, melting ice and feverish heat. Atmospheric scientists have grown increasingly concerned about human-induced global warming in recent years, though political pressures and fierce arguments about climate change have slowed efforts to develop solutions.
The climate center noted that a condition called La Nina developed during July as the waters of the central Pacific Ocean cooled. This is expected to last through the Northern Hemisphere winter 2010-2011.
That could be bad news for the Gulf of Mexico as La Nina years tend to have more hurricanes, and such storms could interfere with the clean up of the oil spilled in that region.
For the United States the center noted that "intense heat either tied, or shattered, July monthly temperature records in several East Coast cities, including Washington, Atlantic City, N.J. and Hartford, Conn."
It was the hottest July on record for Delaware and Rhode Island and every East Coast state from Maine to Florida ranked in its top ten warmest.
Only Montana, Idaho, and Texas had average temperatures that were below-normal for the month.
Rainfall, averaged across the country, was much-above-normal in July, ranking in the 10 ten percent in the 1895-2010 period.
Much of the Plains and Upper Midwest experienced above normal wetness, the climate center noted. "Wisconsin had its second wettest July, while Texas had its fourth, Iowa its fifth and Missouri its eighth" wettest.