DC Says Good-Bye to a Wild November 2020

 

Today’s heavy rain across the DC Metro Area and severe weather potential (primarily east of town) remind me of some of November’s more recent severe weather outbreaks.  Less common than earlier in the year, severe weather still occurs in November as the transition from fall to winter continues.  Severe weather is defined as a thunderstorm that contains one or more of the following: hail 1” in diameter or greater, wind gusts of 58/+ mph, or a tornado.

November 15, 2020: 

The DC Metro Area had a rare severe weather outbreak that was concentrated in the northern suburbs.  A severe thunderstorm watch was issued in the late afternoon for much of the DC Metro Area.  The primary threat during this outbreak was severe, damaging wind gusts with a series of storm reports.  Fortunately, no injuries or widespread power outages were reported in the DC Area.

November 17, 2013:

One of the more significant November severe weather outbreaks in recent memory occurred seven years ago.  This outbreak covered a large area from the Tennessee Valley to the Great Lakes Region to the Mid-Atlantic.  Over 100 confirmed tornadoes occurred from Tennessee to Michigan, with a deadly EF3 tornado in Kentucky that claimed three lives. 

November 16, 2010:

This event was concentrated on the East Coast from South Carolina to New York.  The dominant type of severe weather was severe wind gusts.  There was, however, a confirmed EF-1 tornado in Baltimore, Maryland.  Three injuries were reported from the tornado, which had wind speeds between 86-110 mph. 

Tornado intensity is ranked on the Fujita Scale that was originally created in the 1970s.  However, it was updated and became the "Enhanced Fujita Scale" or “EF Scale” in 2007.  The National Weather Service changed the criteria for severe hail in January 2010.  Prior to this, hail 0.75"/+ (penny-sized) in diameter was considered severe.  However, in order to reduce confusion and the number of severe thunderstorm warnings, the criteria for severe hail was raised to 1”/+ (quarter-sized). 

November 14-16, 2006:

There were over 200 reported cases of severe weather, including 40 tornadoes between November 14 and November 16.  The impact ranged from Louisiana to upstate New York.  Although 168 of the 217 severe weather reports were for wind, one of the tornadoes was especially deadly.  On November 15, the town of Riegelwood, North Carolina suffered eight fatalities during a tornado that destroyed several homes.