Emerging threatsAutumn 2015 was record warm for the contiguous U.S.

Average temperatures continue to climb // Source: cdc.gov

The National Oceanic and Atmospheric Administration (NOAA) ha release a report which shows that the autumn of 2015 was the warmest autumn in the last 121 years — since measurements began in 1895.

The September-November contiguous U.S. average temperature was 56.8°F, 3.3°F above the twentieth century average, surpassing the previous record of 56.6°F set in 1963. Record and near-record warmth spanned much of the nation. The November contiguous U.S. temperature was 44.7°F, 3.0°F above the twentieth century average and the thirteenth warmest in the 121-year period of record.

The autumn precipitation total for the contiguous United States was 8.32 inches, 1.44 inches above the twentieth century average. This was the fifteenth wettest September-November on record for the Lower 48 and the wettest since 2004. The November precipitation total was the fourth wettest on record with 3.30 inches, 1.07 inches above average. Record and near-record precipitation was observed across the Great Plains and Southeast.

This analysis of U.S. temperature and precipitation is based on data back to January 1895, resulting in 121 years of data.

U.S. climate highlights: Autumn (September-November)
Temperature

• Every state across the contiguous United States and Alaska had an above-average autumn temperature. Forty-one states across the Rockies, Great Plains, Midwest, Northeast, and Southeast were much warmer than average. Florida tied its warmest autumn on record with a statewide temperature of 75.5°F, 3.6°F above average.

Precipitation

• Above-average autumn precipitation was observed across parts of the West, Southern Plains, and Southeast. South Carolina had its wettest autumn on record, partially driven by historic rainfall in early October. South Carolina’s autumn precipitation total was 23.62 inches, 13.77 inches above average, and bested the previous record of 18.42 inches set in 1959.
• Below-average autumn precipitation was observed along the West Coast and New England. California, Connecticut, Oregon, and Wyoming were each drier than average for the three-month period.

Extremes

• The U.S. Climate Extremes Index (USCEI) for autumn was 50 percent above average and the tenth highest value on record. On the national scale, extremes in warm maximum and minimum temperatures and one-day precipitation totals were much above average. The USCEI is an index that tracks extremes (falling in the upper or lower 10 percent of the record) in temperature, precipitation, land-falling tropical cyclones, and drought across the contiguous United States