What’s normal is changing

Posted at 4:03 PM, Apr 11, 2012
and last updated 2012-04-11 16:08:44-04

Last winter wasn’t normal.  Not by a long shot.  It’s usually not 70 or 80 degrees in January and February.  But when we tell you our “normal” high temperature for a date, how is that number calculated?

In Hampton Roads, our weather records date back more than 140 years to the early 1870s.  For example, we can tell you that the coldest April 12th on record was in 1880 when we dropped to 24 degrees.  But “normals” are based on just 30 years of records.  Right now, what’s “normal” is an average of our temperatures between 1981 and 2010.  At the end of each decade, the earliest decade is dropped and the most recent decade is added.  So last year, our normals were calculated based on the 30 years between 1971 and 2000.  So “normal” can sometimes change.

Want to check out our normal temperatures and weather records?  Here’s a link:

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Patrick Rockey
NewsChannel 3 Chief Meteorologist