WEST JEFFERSON-Some of the nation’s best weather minds believe this winter should be warmer and dryer than average, at least here in the southeast.
That’s according to a long term winter weather outlook issued by the National Oceanic and Atmospheric Administration last month.
Agency forecasters said in October they expected La Nina to influence winter conditions this year, and updated that guidance last week by issuing a “La Nina Advisory,” a phenomenon which describes a cooling of the water in the equatorial Pacific that favors drier, warmer winters in the southern United States and wetter, cooler conditions in the northern U.S.
Last week, NOAA left the probability for weak La Niña to persist through the Northern Hemispheric winter months unchanged at 55 percent.
“This climate outlook provides the most likely outcome for the upcoming winter season, but it also provides the public with a good reminder that winter is just up ahead and it’s a good time to prepare for typical winter hazards, such as extreme cold and snowstorms,” said Mike Halpert, deputy director, NOAA’s Climate Prediction Center in October. “Regardless of the outlook, there is always some chance for extreme winter weather, so prepare now for what might come later this winter.”
Other factors that often play a role in the winter weather include the Arctic Oscillation, which influences the number of arctic air masses that penetrate into the South and create nor’easters on the East Coast, and the Madden-Julian Oscillation, which can affect the number of heavy rain events in the Pacific Northwest.
NOAA broke its national Winter Outlook – December 2016 through February 2017 – into three categories precipitation, temperature and drought categories.
The agency said drier than normal conditions are most likely across the entire southern United States and southern Alaska, along with wetter than normal conditions in the northern Rockies, around the Great Lakes, in Hawaii and in Western Alaska.
We can couple that with warmer than normal temperatures across the southern United States, according to NOAA. The agency also said drought will likely persist through the winter across many regions currently experiencing it, and could expand in the southeast.
Much of western North Carolina has been hit hard by drought through the summer and fall and is currently experiencing an added hit in the form of multiple wildfires.
The agency cautioned that its seasonal outlook doesn’t project where or when snowstorms may hit or provide total seasonal snowfall accumulations.
“Snow forecasts are dependent upon the strength and track of winter storms, which are generally not predictable more than a week in advance,” according to a press release issued by NOAA. “However, La Nina winters tend to favor above average snowfall around the Great Lakes and in the northern Rockies and below average snowfall in the mid-Atlantic.”
Reach Adam Orr at 336-846-7164.