![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTYdsHcznRws_4EFS-zcBwqFuwE8hi1HM2fExooKG7I_XqT1Kc7COncdwZCSv7JjVCwq2KcpOTlO5dd33CmiGVWY-yfnVY5E4OqHjA4Ye1Py7v4ifRMjDx9iUB2pzG4-8DBcaHY_hHm06n/s320/fig01_rockvalleyIAtor_4in.gif)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjg6lpRJUF5SrwaHSgZ9yXYsc4xZKFr8NMG41-PyORCu3WTsPo2dwKOYfaEatWB5eNNjAUCgSP79gzxMcdflNV_WoH1qjhXq9GgGjdTeoFUP8NQlpBWORvGT6qo-RqJ8emQBFkW4im8mQ54/s320/fig07_windsorCOtor.gif)
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The paper focuses on 3 strong tornado events (see photos above) that were difficult to forecast in 2008:
- May 1 in northwest Iowa (F2 tornado near Rock Valley)
- May 22 in Colorado (the F3 Windsor tornado, with 1 death)
- June 6 in north-central Minnesota (F2 and F3 tornadoes near Park Rapids)
These had some features and ingredients that were similar to so-called "cold-core" events, but probably wouldn't be considered as such using a rigid definition. While the paper is not anything "earth-shattering", I hope some people find the case studies useful.
- Jon Davies (updated 10/22/08)