Welcome to the SVRGIS page for the SPC. This page has the United States severe report database (tornadoes 1950-2011, hail/wind 1955-2011), converted into shapefile (.shp) file format as well as a Geographic Information System (GIS) database. Additional data available for download include census and topographic datasets, among others. The data can be viewed in graphical, tabular, and statistical formats depending on end-user programs.

The NOAA/NWS Geodata page, has links that are directed to free, easy-to-use GIS viewing programs.

The data originate from the comma separated value (.csv) files available at:
http://www.spc.noaa.gov/wcm/#data

The column headings are the same as those described in this document:
http://www.spc.noaa.gov/wcm/SPC_severe_database_description.pdf

Location Codes for Storm data here.

Map of State FIPS Numbers here.

Text list of County FIPS Numbers here.

The data were prepared in a USA Contiguous Lambert Conformal Conic projection with North American Datum 1983. The data are contained in zip files and can be quite large, up to around 55MB (i.e. Cities.zip). The 2012 update contains a prepared .mxd file as a base template for users with programs capable of viewing .mxd files. An instructional manual is provided on how to build and develop a basic severe weather report GIS database in ArcGIS.

Disclaimer: The quality of tornado data prior to the mid 1990s featuring a beginning and end point (i.e. tornado track.shp) is incomplete for most tornadoes. A more complete record of tornado track data began in the mid 1990s. Documentation of hail and wind swaths began in 2006 in select areas. However, swath information is limited to very few events.