While last month was the 13th warmest March in the period of record dating to 1880, it was the coolest one in 11 years.
That had a lot to do with the widespread cooling of the tropical Pacific, known as La Nina, said Jessica Blunden at the National Climate Data Center.
She noted that the 2000 cooler readings also were related to La Nina.
The combined land and sea temperatures came to 57.58 Fahrenheit in March, according to the climate center report released this afternoon, or 0.88 above the 20th Century average.
That's a significant dip from the record 58.1 of March 2010, when the tropical Pacific was a whole lot warmer.
The first quarter of last year marked the warmest start to a year ever, and the first quarter of 2011 has been the 11th warmest.