I was hasty in proclaiming this year’s tornado season the worst ever, picking up a chart from NOAA that showed more tornadoes reported at this point than in any year prior.
Claire Wilkinson over at Terms + Conditions looks at the tornado stats in detail:
But before we jump to conclusions about record-breaking numbers, it’s important to read the fine print.
First, these figures from NOAA’s Storm Prediction Center are a preliminary count of eyewitness reports for tornado events not a count of actual tornadoes.
SPC also cautions that comparisons between preliminary counts and actual counts from prior years should be avoided.
An article by the Dallas Weather Examiner points out that if all the 871 tornado reports during April 2011 verify for separate tornadoes, then this would eclipse the current monthly record of 542 tornadoes from May 2003.
But it goes on to suggest that because many of these reports are duplicates, the verified tornado total for April 2011 will probably come in below 542. This would leave May 2003 with the highest tornado count for any month.
In my (lame) defense, I picked up the screen grab from Eqecat to emphasize the main story, which was Eqecat’s estimate that last week’s tornadoes caused $2B to $5B in losses. But I should have gone back to verify.