The lack of an El Nino or La Nina global climate pattern makes for an unpredictable winter in Maryland and many other parts of the country, according to a NOAA season outlook released Thursday.
The National Oceanic and Atmospheric Administration's Climate Prediction Center in College Park is calling for equal chances for above- and below-normal precipitation and temperatures this winter in the mid-Atlantic.
"This year's winter outlook has again proved to be quite challenging," Mike Halpert, the climate center's acting director, said on a conference call with reporters. He called seasonal climate forecasting "still a young and evolving science."
But the law of averages might suggest more than a few inches of snow in the Baltimore-Washington region, added Halpert, who is based in the Washington area.
"The odds, if you're a betting man, would not favor a third year in a row with under 5 inches total," Halpert said.
In many years, the forecasts are helped by the presence or expectation of El Nino and La Nina, global climate patterns linked to Pacific Ocean surface temperatures, Halpert said. Those conditions can lock in weather patterns that cause outlier years when it comes to little or lots of snowfall, and while that isn't expected this winter, "we never rule it out," Halpert said.
El Nino winters are typically marked by above-average snowfall in Maryland, such as during the record-setting winter 2009-2010. La Nina winters, on the other hand, are typically mild with little snow, such as winter 2011-2012, when only 1.8 inches of snow fell in Baltimore.
But the globe has been under what are considered "neutral" conditions, neither El Nino or La Nina, since spring 2012, and that is expected to continue through the winter.
A lack of "strong or reliable enough climate signals" means equal chances of anything for the mid-Atlantic. Elsewhere, below-average precipitation and above-average temperatures are expected in the Southeast as well as above-average temperatures in New England.
NOAA's forecast appears conservative compared with private forecasters' season outlooks. AccuWeather.com calls for a mild start to the winter for the eastern U.S., with more snow than last year in the mid-Atlantic but less in New England.
The Farmers Almanac predicted "copious" amounts of precipitation in the mid-Atlantic, though it left it up in the air whether it could fall in the form of rain or snow.