Winter weather outlook uncertain due to stronger El Nino

Forecasters are keeping a close eye on a rapidly strengthening El Niño in the tropical Pacific Ocean and they say it could have a major influence on weather across the United States this fall and winter.

The National Oceanic and Atmospheric Administration says there is now more than a 90-percent chance that El Niño will reach very strong levels during the Northern Hemisphere fall and winter.

NOAA is also putting the odds at about 75 percent that the October-through-December period could reach what it describes as historic-strength El Niño conditions.

El Niño occurs when ocean water in the central and eastern tropical Pacific becomes significantly warmer than normal. That extra heat can alter the jet stream and atmospheric circulation thousands of miles away, changing weather patterns across North America.

For the Atlantic hurricane season, El Niño is generally bad news for tropical storm development.

The warmer Pacific waters contribute to stronger winds aloft across the Atlantic tropics. That wind shear can disrupt developing tropical systems before they have a chance to strengthen.

The result has been an unusually quiet Atlantic hurricane season so far.

But forecasters caution that El Niño does not completely eliminate the threat of a late-season hurricane or tropical storm. The Atlantic hurricane season continues through November 30th, and conditions can change quickly.

For Virginia and the Eastern Shore, the bigger question may be what happens this winter.

Strong El Niño events typically favor a warmer and wetter pattern across parts of the southern United States. The Mid-Atlantic is more complicated.

El Niño can increase the potential for stormy weather along the East Coast, but whether those storms produce rain, snow or ice depends on the position of the jet stream and other atmospheric patterns.

That means a strong El Niño does not necessarily mean a snow-free winter in Virginia.

In fact, even during a very strong El Niño, the right combination of cold air and an East Coast storm track can produce significant snowstorms or nor’easters.

Forecasters expect the current El Niño to remain influential into early 2027, with a possible return toward neutral Pacific conditions during the spring.

For residents of the Eastern Shore, the message is simple: El Niño is becoming a major player in the weather pattern — but it is still too early to say exactly what kind of winter Virginia will experience.

Weather forecasters will be watching the Pacific closely in the coming weeks, because the strength and location of the warming there will help determine the weather pattern across the United States as we head toward winter.