Winter weather forecast shows colder, wetter North and warmer, drier South

NOAA released its U.S. Winter Outlook showing La Niña influence shifting weather

The weak La Niña developing could be the biggest player in the 2017-2018 winter forecast, said Mike Halpert, deputy director of the Climate Prediction Center at NOAA, which released the U.S. Winter Outlook today.

The phenomenon could cause colder and snowier conditions for the north-central U.S. and warmer and drier than normal conditions for the southern U.S, from California to Florida.

The areas around the Great Lakes could also see an increase of Lake Effect snow.

La Niña is the opposite of El Niño; together, they are called the El Niño-Southern Oscillation, or ENSO, and often cause significant differences from average ocean temperatures, winds, surface pressure, and rainfall across parts of the tropical Pacific, according to NOAA.

La Niña is the cool phase of the equatorial Pacific Ocean, as opposed to the warm phase El Niño. The pattern usually swings back and forth about every 3 to 7 years, according to NOAA.

For the Pacific Northwest and the northern Rockies, cooler and wetter than normal conditions are forecast, which means more strong storms with damaging winds and flash flooding for Seattle and Portland are likely.

More than normal snow is forecast for the ski resorts in the northern Rockies from Big Sky Resort in Montana to Steamboat Springs in Colorado.

After a record breaking 2016-17 snow season in the Sierra Nevada Range Mountains, this snow season looks closer to normal. Southern California could be slightly milder and drier than normal.

ABC News' Bianca Seidman contributed to this report.