DALLAS -- The continental United States endured the hottest summer since the Dust Bowl era of the 1930s, and the second-warmest since recordkeeping began more than a century ago, US forecasters said yesterday.
A July heat wave that set more than 2,300 daily high-temperature records across the nation and 50 new overall records contributed to an average temperature between June and August of 74.5 degrees. That's just shy of the 1936 record of 74.7 degrees and well above the 20th-century average of 72.1 degrees.
The warm summer helped make the first nine months of the year the warmest January-to-August period since recordkeeping began in 1895, surpassing a record set in 1934, the National Oceanic & Atmospheric Administration said.
Eight of the past 10 US summers have had above-average temperatures, NOAA said.
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http://www.boston.com/news/nation/articles/2006/09/15/summer_was_warmest_since_30s/