Normally rainy and cool Hilo set a string of high-temperature records over the summer, and now it’s official: 2015 was the hottest year on record for the area.

The average temperature of 76.2 degrees last year was about 2.3 degrees above the average for Hilo and was the hottest it’s been at Hilo Airport in the 66 years that records have been kept there, according to the National Centers for Environmental Information, which released its annual report on temperature anomalies.

Blame it on El Nino, the warming of ocean temperatures around the islands, National Weather Service forecasters said.

“A lot of our temperatures near the coastal waters are regulated by coastal temperatures,” said Matthew Foster, a meteorologist with the Honolulu office of the weather service.

If ocean temperatures around Hawaii are unusually warm, as happens during an El Nino year, the temperatures on land will also be warmer than normal, he said.

Hilo wasn’t the only place in Hawaii that was unusually hot last year.

Lihue’s average 2015 temperature of 77 degrees was about 1.2 degrees above the 1981-2010 average, making it the second-warmest year at Lihue Airport since the weather service began keeping records 65 years ago.

Honolulu’s 78.7 average last year was a degree above average, making it the fourth-warmest year in 66 years of record-keeping.

Kahului had an average temperature of 77.2 degrees, about 1.3 degrees above average — the sixth-warmest year in six decades of record-keeping at Kahului Airport.