2015 was America's second-hottest year on record

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2015 was record-breaking hot, with the year marking America's second-hottest since record-keeping began and December snagging the title of the warmest December ever. Scientists from the National Oceanic and Atmospheric Administration announced Thursday that the average temperature in 2015 was 54.4 degrees Fahrenheit — 2.4 degrees above average — putting it narrowly behind record-holding 2012, which averaged 55.3 degrees. 2015's unseasonably warm December was a whopping 6 degrees above the century's average for the month.

This marks the 19th consecutive year that U.S. temperatures have been higher than the 20th century average. NOAA says that although 2015 didn't mark America's hottest year, it's "extremely likely" this year's global average will shatter records.