A rare triple-dip La Niña is looking increasingly likely for the Northern Hemisphere. The latest outlook by NOAA’s Climate Prediction Center, released Thursday, indicates there’s a 62% to 66% chance the current La Niña climate condition will persist through fall and early winter.
If that happens, it’ll be the third La Niña winter in a row – a rare phenomenon we’ve only seen twice since 1950. A third consecutive La Niña year would likely have a major impact on California.
The La Niña climate pattern usually splits the country into two, bringing a dry winter to the southern half and a wetter winter to the northern half.
This year, however, the dividing line was further north. While parts of Washington and Oregon are out of the drought, a dry La Niña winter and spring have left 99.8% of California suffering drought conditions.
Another dry winter would be worse news for California than it would for the rest of the country.
“We’ve got significant, significant drought in the Southwest and California and their normal rainy season is the winter,” Halpert said. “Here in the Washington, D.C. area, it generally rains all year round. So if we have a couple of dry months, it’s OK because we can make it up another time. When you’re in California and the Southwest, 90% of the rain falls in that fairly short winter and spring season. So if you miss that, you’re not going to make that up when you get into the summertime.”
Other parts of the country, like the Pacific Northwest, could see more precipitation as the result of a triple-dip La Niña. There could also be more precipitation for the Midwest and parts of the South later in the winter, specifically Ohio and the Tennessee Valley.