Flowers are pushing out of the ground in New Jersey. Ice fishing tournaments in Minnesota are being canceled for lack of ice. And golfers are hitting the links in Chicago in January.

Much of the U.S. Midwest and East Coast is going through a remarkably warm winter.

New York City saw a November and December without snow for the first time since 1877. And New Jersey had its warmest December since records started being kept 111 years ago.

Learn more about the science behind the world you live in FOXNews.com's Natural Science Center.

Not only are crocus bulbs blooming in Maria Freitas' backyard in New Jersey, but the asparagus is 3 inches high.

"They think it's spring. They're so confused," she said.

Forecasters said the mild winter does not necessarily mean global warming is upon us.

Meteorologists say the warm spell is due to a combination of factors. El Nino, a cyclical warming trend now under way in the Pacific Ocean, can lead to milder weather, particularly in the Northeast. The jet stream, the high-altitude air current that works like a barricade to hold back warm Southern air, is running much farther north than usual over the East Coast.

The weather is prone to short-term changes. In fact, the Midwest has been hit by back-to-back blizzards in the past two weeks.

At the Marovitz Golf Course in Chicago near Lake Michigan, 30 people teed off one morning, when there are usually no golfers this time of year.

But the mild weather is also hurting some businesses and events.

In Minnesota, where a water skier in a wetsuit was recently seen on the Mississippi River, ice fishing tournaments have been canceled.

And organizers of the St. Paul Winter Carnival, scheduled to begin late this month, said the ice is not thick enough to harvest into 1,400 blocks for the ice maze. They may have to switch to plastic.

In New Jersey, the Mountain Creek ski resort in Vernon is struggling to open more trails. There have not been many nights cold enough to make snow.

"We're keeping our fingers crossed that the cold weather will get here soon," resort spokeswoman Shannon McSweeney said. "Either that, or sending trucks out to Colorado to steal some of their snow."

Get complete coverage in FOXNews.com's Natural Science Center.