Closing Notice: The Library’s Community Outreach & Literacy Services office, located near 29th and Harvard, will be closed on February 28th & March 1st for building renovations.
The Storm Prediction Center of the National Weather Service includes maps, tracks, averages and summaries that apply to tornadic activity in the United States. The Norman office of the National Weather Service keeps a historic list of tornado data by county. The EF Scale became operational on February 1, 2007 and is used to assign a tornado a 'rating' based on estimated wind speeds and related damage.
Source: National Weather Service web sites.