What Can Washingtonians Expect this Winter?

As we get deeper into autumn, people start to wonder about winter

As I wrote about recently, the current El Nino event that’s developed in the Pacific Ocean has become the strongest since the late 1990s. That could be a good thing for the drought-stricken western United States, especially California in particular typically sees above average rainfall during an El Nino winter.  An El Nino event is characterized by warmer than average sea surface temperatures in the central and eastern equatorial Pacific Ocean that leads to global weather repercussions.

Washingtonians may wonder what influence, if any, El Nino may have on the upcoming winter season. NOAA recently issued its seasonal outlook that’s taken El Nino into account. It’s calling for a slightly above average potential for a warmer and wetter than average winter in the Mid-Atlantic Region. That’s not unusual for this part of the country during a strong episode of El Nino. During the significant 1997-1998 El Nino, the Nation’s Capital had its least snowy winter on record.

Prior to the 1997-1998 El Nino, the previous strongest El Nino event on record came during the 1982-1983 winter season.   The Mid-Atlantic Region saw one of its largest snowstorms that winter, since the ideal combination of cold air and favorable storm track came together. Longtime Washingtonians will remember that totals ranging from 16.6” downtown on February 10-11, 1983, to 22.8” at both Dulles Airport and in Baltimore.

The Mid-Atlantic Region has had two of its snowiest winters during what NOAA describes as “moderate” El Nino events: during the 2002-2003 and 2009-2010 winter seasons. In fact, the 2009-2010 winter season was the snowiest on record when 56.1” of snow fell in Washington, D.C. (compared to a seasonal snowfall average of 15.4”). That helps illustrate that whether or not there’s an El Nino event, it only takes one significant winter storm to make the entire winter season snowier-than-average for the Mid-Atlantic Region.  However, specific winter storms are generally not predictable more than a week in advance.