The year 2012 was the warmest on record in the contiguous United States, a government climate agency said on Tuesday.

Scientists at the National Oceanic and Atmospheric Administration said the average temperature across the US, excluding Alaska and Hawaii, was 12.94 C, 0.6 C above the previous hottest year on record, 1998.

The agency also confirmed what many farmers in the Midwest and many residents in the West of the country must have suspected - it was an exceptionally dry year, the 15th driest on record.