From NOAA:
Record December boosted 2015 to 2nd warmest year for Contiguous US
Ten weather, climate disasters exceeding $1 billion impacted the nation
The 2015 annual average U.S. temperature was 54.4°F, 2.4°F above the 20th century average, the second warmest year on record. Only 2012 was warmer for the U.S. with an average temperature of 55.3°F. This is the 19th consecutive year the annual average temperature exceeded the 20th century average. The first part of the year was marked by extreme warmth in the West and cold in the East, but by the end of 2015, record warmth spanned the East with near-average temperatures across the West. This temperature pattern resulted in every state having an above-average annual temperature.
The average contiguous U.S. precipitation was 34.47 inches, 4.53 inches above average, and ranked as the third wettest year in the 121-year period of record. Only 1973 and 1983 were wetter. The central and southeastern U.S. was much wetter than average, while parts of the West and Northeast were drier than average. The national drought footprint shrank about 10 percent during the course of the year.
In 2015, there were 10 weather and climate disaster events, each with losses exceeding $1 billion. These events included a drought, two floods, five severe storms, a wildfire event and a winter storm. Overall, these resulted in the deaths of 155 people and had significant economic effects. Further cost figures on individual events in 2015 will be updated when data are finalized later this year.
U.S. climate highlights: 2015
Much warmer than average annual temperatures were observed across the West, Northern and Central Plains, Southeast, and Mid-Atlantic. Twenty-eight states, including Alaska, were much warmer than average during 2015 — Florida, Montana, Oregon and Washington were record warm. Alaska, California, and Idaho had their second warmest year.
Most of the central and southeastern U.S. were wetter than average, including 14 states that were much wetter than average. Oklahoma and Texas were record wet for the year, with both states becoming drought free for the first time since 2010. Parts of the Northeast and West were drier than average. Connecticut had its fourth driest year. In California, year-end precipitation helped erase early-year deficits, resulting in the state’s 13th driest year. The U.S. Climate Extremes Index (USCEI) for 2015 was 70 percent above average, ranking as the fourth highest annual USCEI in the 106-year record and highest since 2012. The components of the USCEI that were much above average for the year included extremes in warm maximum and minimum temperatures, one-day precipitation totals and days with precipitation. The USCEI is an index that tracks extremes (falling in the upper or lower 10 percent of the record) in temperature, precipitation, drought and land-falling tropical cyclones across the contiguous United States.
