The National Weather Service’s Climate Prediction Center says we’re in a La Niña watch, with a 60% chance for the climate pattern to emerge by the end of November and with the possibility to persist through March.

The mid-Atlantic region sits between the northern part of the country, which can expect wetter conditions that normal, and the southern, which can expect warmer conditions than normal, according to a map published by the National Ocean Service.

Maryland may face warmer conditions whether La Niña emerges or not. The latest long-range forecast by the Climate Prediction Center shows the state has a chance of having above-normal temperatures this winter.

The long-range forecast does not show changes in expected precipitation for Maryland, though it does show dryer conditions farther south, which is expected for a La Niña year.

Tom Di Liberto, a climate scientist and public affairs specialist with NOAA, wrote that La Niña has historically meant below-average snowfall for mid-Atlantic winters. Di Liberto looked at 22 La Niña events on record and found 15 of them had below-average snowfall for the area around Maryland.

Scientists are expecting the La Niña, if it develops, to be weak, which historically has resulted in below-average snowfall in the region.

What is La Niña?

La Niña and its opposite, El Niño, are climate patterns that disrupt the normal or standard conditions in the Pacific Ocean. When the east-to-west trade winds in the tropics become stronger than normal, they push warm water toward Asia.

When that happens, parts of the Pacific Ocean off the coast of South America get cooler than usual surface water temperatures. That’s the climate pattern that La Niña describes.

The cold waters in the Pacific push the atmospheric jet stream north, which is what ultimately leads to expected heavy rains in the Pacific Northwest and drought in the Southeast. La Niña can also lead to stronger Atlantic hurricane seasons.

Scientists confirmed El Niño conditions last summer and the region saw a warmer and wetter winter than normal. El Niño and La Niña cycles typically happen every 3-5 years or so.