Return to API Services. This service drives some of the presentation of the VTEC Browser.
This service provides a GeoJSON for the intersection of the polygon border and any county/parish borders. This is meant to describe the amount of the polygon border that was influenced by the county border.
Changelog
- 2026-04-27: The VTEC eventid name was rectified to etn to match other IEM services.
- 2024-08-16: Initial documentation update
Example Usage
Show the intersection of the polygon border for Des Moines Tornado Warning 49 from 2024 with county borders.
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. |
| wfo | string | Three character WFO field. You may optionally specify this as a four character full identifier. |
| year | integer | Year between 1986 and the current year for which the IEM database may have VTEC records. |
| phenomena | string | Two character (uppercase) VTEC phenomena code. |
| significance | string | One character (uppercase) VTEC significance code. |
| etn | integer | VTEC Event ID |