Radar images are centered on SPC severe weather reports and extracted from the closest hourly data in GridRad which can be downloaded from the Research Data Archive. The original ~2x2km 3D data are converted to 2D by calculating the column maximum reflectivity. These values are then converted to 8-bit integers and interpolated to a 3.75 km Lambert conformal conic grid using nearest neighbor. The 136 x 136 dimensions result in a region approximately 512 x 512 km.
136 x 136 pixel (~512 x 512 km) images with units of dBZ. The center of the radar image is the location of the report. You can download the raw data, view individual maps centered on reports, or view all reports on an interactive map for each year.
Geogrid parameters:
Description of the columns in the CSV are as follows:
The unid column is based on the report time in UTC and "om" identifier from the "1950-2018_actual_tornadoes.csv" file on the SPC severe weather reports page. You should be able to easily join these data with those data to attach more attributes.
The data are provided at no cost, as-is, with no warranty of any kind. No modification of either the SPC reports or the GridRad data (beyond interpolation) is done before these data are hosted on the website. The process is completely repeatable from start to finish, assuming you have patience or access to a supercomputer cluster. Please examine the GridRad and the SPC severe weather reports pages to read about the caveats and issues with those data before using these data.
| Severe reports closer to 30 minutes after the hour will have images with displaced reflectivity and the level of displacement is dependent on storm motion. |
| No attempt is made to remove reports with incorrect positions or those that have no radar data. A csv is provided that includes basic radar reflectivity statistics which make it possible to filter these events. |
| The 3.75 km LCC Grid has larger grid spacing than the original data. This will result in some detail being lost. This was a decision made to reduce the size of the dataset on disk and on GPU. |
| The raw data are originally "upside down" because of how the grid was defined. The image browser on this website provides flipped images. However, the tarball data will have the original orientation that matches up with the LCC grid. Please take the time to examine what you are throwing into your ConvNet! |
We are generating these data solely because we think they would be of interest to the meteorology and climatology community. That being said, we would like to get some credit if you find them useful!
Haberlie, A. M., W. S. Ashley, and M. Karpinski, 2020: Mean storms: Composites of radar reflectivity images during two decades of severe thunderstorm events. International Journal of Climatology, In Press.
Bowman, K. P., and C. R. Homeyer. 2017. GridRad - Three-Dimensional Gridded NEXRAD WSR-88D Radar Data. Research Data Archive at the National Center for Atmospheric Research, Computational and Information Systems Laboratory.