Good Question: What Is El Nino?

MINNEAPOLIS (WCCO) -- Temperatures are forecasted to be well above average all week. And all signs point towards us heading for an El Nino winter.

So what exactly is El Nino? Good Question.

"Minnesota winters can be daunting on even the hardiest of dogs," said a dog walker near Lake Calhoun in Minneapolis.

There's no such thing as the "dog days of winter." But if there was, maybe a week of 45 degree temperatures would qualify.

"I would have thought there would be ice on the lake," said another walker.

WCCO Chief Meteorologist Chris Shaffer is fully aware of the lack of snow and mild temperatures for December.

"In the simplest term, El Nino is the warming of the ocean waters of the Pacific along the equator," Shaffer said.

And that has a major effect on weather patterns across the U.S. It moves warmer air our way. Shaffer said the polar jet that gave us the frigid and famed "polar vortex" a couple years ago is playing a different role this year.

"The polar jet during El Nino typically kicks further north into Canada. And that's what keeps us in the warmer air and also takes many of those storm systems and they pass to the north," Shaffer said.

That could mean more rain in the southern states and drier weather around the Great Lakes. Here, it could mean a milder winter which is good for some and bad for others.

But an El Nino winter doesn't mean it won't get cold at some point. El Nino can't completely stop winter from being, as they say, muy frio.

"Our coldest time of the year, generally we are in the low 20s. We could still have that and I still think we will have cold snaps. But probably not 'this is our 8th consecutive day below zero.' I don't think we'll see that," Shaffer said.

Fishermen off the coast of south America first recognized warmer weather patterns in the Pacific Ocean in the 1600s. They chose the name El Nino because it means "little boy" or "Christ Child" in Spanish - because these warmer patterns tend to occur in December around Christmas time.