La Niña Has Arrived In MD: What Forecasters Say It Means

La Niña has officially returned to the Mid-Atlantic and is expected to stick around for the next five months, the National Weather Service confirmed last week.

The weather pattern is expected to be weak compared to past years, but it could shape just what sort of winter Maryland experiences. La Niña winters have historically brought generally cooler, wetter conditions to the North and milder and drier conditions to the South.

In August, the Climate Prediction Center issued a La Niña watch, estimating a 56 percent chance that La Niña would emerge in October. That’s in line with current expectations.

In the past week, sea surface temperatures have been about 0.9 degrees below average across the eastern tropical Pacific, signifying the start of a weak La Niña.

The agency now projects a 71 percent chance that La Niña continues into December and a 54 percent chance of it lingering into February. Thereafter, a springtime shift toward neutral or weak El Niño conditions is likely.

Here's what to know about the climate pattern and how it's expected to affect Maryland.

La Niña, which means "Little Girl" in Spanish, is a climate pattern that brings increasing upwelling and cold, nutrient-rich water to the surface of the Pacific Ocean to the west of the United States, according to the National Oceanic and Atmospheric Administration.

La Niña is a cold event. The cold waters it brings to the surface of the ocean lead to droughts in the Southern part of the United States and heavy rain and flooding in the Pacific Northwest, according to weather officials.

Below-average temperatures on the surface of the ocean in September indicated the return of La Niña — the fifth time in six years, according to The Washington Post.

The National Oceanic and Atmospheric Administration on Thursday that La Niña conditions emerged in September and are likely to remain though February, according to NOAA.

"A weak La Niña would be less likely to result in conventional winter impacts, though predictable signals could still influence the forecast guidance," NOAA forecasters wrote in their monthly ENSO update.

However, weather officials predict that there is at least a 50% chance that the effects of La Niña will be weak this time around, leading to fewer impacts through the winter.

"Based on recently observed anomalies, the team favors La Niña to continue through winter," the National Weather Service Climate Prediction Center concluded. "In summary, La Niña conditions are present and favored to persist through December 2025 - February 2026, with a transition to ENSO-neutral likely in January-March 2026 (55% chance)".

Although La Niña often means a mix of winter precipitation in Maryland as the jet stream and air masses pour over the Appalachians, The Post said, this year’s signal is mixed.

The Climate Prediction Center is calling for above-average temperatures across most of the Lower 48 into December.

Even if a La Niña fizzles out this winter, there may be times when weather patterns remains consistent with La Niña — for example, with the warmer weather across the southern U.S., according to AccuWeather, a weather forecasting company.

It also leaves room for ocean factors to influence the forecast, according to AccuWeather Senior Meteorologist and Long-Range Expert Paul Pastelok, including a marine heat wave that will span across much of the Northern Pacific Ocean.

"These waters off the West Coast and extending farther out are very, very important going into our [winter] forecast this year," Pastelok explained.

SEE ALSO:

• 2025-26 Winter Forecast: Here's How Snowy And Cold It Will Be In MD
• ‘Snowy Nor’easters’: Here’s What To Expect From Winter 2025-26 In MD
• 'Wild Ride' Of A Winter For MD Predicted In New Long-Range Forecast