Changelog

• 2024-07-09: Add csv and excel output formats

Example Requests

Return all watches that had a polygon coincident with the point at 41.9N, 93.6W

https://mesonet.agron.iastate.edu/json/spcwatch.py?lat=41.9&lon=-93.6

Return all watches that were valid at 2024-08-01 00 UTC, sorry that this uses a lame format, will update to ISO8601 soon.

https://mesonet.agron.iastate.edu/json/spcwatch.py?ts=202408010000

Return the above, but in CSV format

https://mesonet.agron.iastate.edu/json/spcwatch.py?ts=202408010000&fmt=csv

And now excel

https://mesonet.agron.iastate.edu/json/spcwatch.py?ts=202408010000&fmt=excel

CGI Arguments

The following table lists the CGI arguments that are accepted by this service. A HTTP GET request is required. Fields of type Multi-Params or CSV value can accept either a comma separated list or multiple parameter and value combinations. For example, ?foo=1&foo=2 is equivalent to ?foo=1,2.

Field	Type	Description
callback	string or null	Legacy JSON-P style callback. It is likely best to not depend on this usage. The IEM website has a permissive CORS.
fmt	string	The format to return data in: geojson, excel, or csv
ts	string or null	The timestamp to query for
lat	number	Latitude (decimal degrees) of point of interest
lon	number	Longitude (decimal degrees) of point of interest