Relative Tornado Probabilities Explained

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If you read the comments in the posting below, "Tornado Threat Today," you see the comment,


Anonymous said...Great. Omaha again in the cross hairs. At least it is a relatively small chance.



One of the Meteorological Musings readers replied, 

If I remember correctly, Joplin was in a 10% hatched area on May 22 so those probabilities are nothing to sneeze at.  Elaine




Elaine is correct (see below).

Actually, a 15% chance of a tornado in these outlooks is a very significant risk.  Lets take a look at the tornado probabilities attached to the 8am severe weather outlooks on two other days this season:

St. Louis Good Friday Tornado April 22nd
North St. Louis County was in the 5% area without hatching.
The Good Friday tornado was F-4 intensity.
Joplin Tornado May 22nd
Joplin was in the 10% area with "hatching" (potential for F-2 or greater tornadoes)
So, when you find yourself in a 10% or 15% (or higher) tornado forecast it is something to take seriously.

Since posting this morning, a new outlook has been released by the Storm Prediction Center and these are the latest probabilities for later this afternoon and tonight.
Relative probabilities of a tornado for Sunday, June 26, 2011,  issued 11:30am.

You can keep track of current watches and warning with AccuWeather here.

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