05.08.11
Mid-May Tornado Count
A look at the preliminary number of tornado reports so far this year shows a general lack of tornadoes west of I-35 in the Plains.
It is nearly mid-May already, and this year is proving especially difficult for Plains storm chasers, despite the large number of tornadoes so far.
The following graph shows the running count of tornado reports this year as compared to the average annual number based on tornado reports from 2005 through 2010. As you can see, a few tornado outbreaks in April have brought this year’s tornado report count to nearly twice the average.
The following graph shows the “inflation-adjusted” number of tornadoes for 2011 (adjusted to account for some tornadoes being counted more than once) compared with percentiles based on averages from 1954 through 2007. Again, note that we are currently well above the maximum recorded number of tornadoes for this time of year!
Are the Plains going to heat up any time soon? That remains to be seen. It does look like at some point this week we may get a dryline day in western Oklahoma, perhaps on Wednesday, that may yield some tornadic supercells. There also may be a chance for some supercells and chasing weather later in the month.
The map and charts are from the Storm Prediction Center, and can be found at the following links: http://www.spc.noaa.gov/climo/online/monthly/2011_annual_summary.html and http://www.spc.noaa.gov/wcm/.