From Greg Carbin at the NWS’s storm prediction center a map how many times each county was under a tornado watch in 2010:
The watches reflect the above normal tornado season in Mississippi and parts of the northern Plains. It also shows the effects of a two-day severe weather outbreak in Arizona. With the exception of May 10, it was a below normal year in parts of Kansas and Oklahoma.
A “PDS” tornado watch = “particularly dangerous situation.” They are only about 5% of tornado watches. When you have a PDS for your area, you really need to pay attention.