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Documentation for /json/wpcoutlook.py
This service provides access to the Weather Prediction Center's Excessive Rainfall Outlook products. The service is designed to be called with a latitude and longitude point.
Changelog
- 2026-02-24: For IEM consistency, the generation_time root attribute was renamed generated_at.
- 2025-06-29: Initial implementation of WPC Outlook service.
Example Usage
Get all the day 1 outlooks for Pierre, South Dakota. First in JSON, then CSV, and finally Excel.
https://mesonet.agron.iastate.edu/json/wpcoutlook.py?lat=44.368&lon=-100.336&day=1 https://mesonet.agron.iastate.edu/json/wpcoutlook.py?lat=44.368&lon=-100.336&day=1&fmt=csv https://mesonet.agron.iastate.edu/json/wpcoutlook.py?lat=44.368&lon=-100.336&day=1&fmt=excel
Provide the day 1 outlook for Pierre, SD valid at 8 UTC on 3 Aug 2024
Get only the last day 2 outlook for Washington, DC
https://mesonet.agron.iastate.edu/json/wpcoutlook.py?lat=38.907&lon=-77.037&day=2&last=1
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, json, excel, or csv |
| lat | number | Latitude (decimal degrees) of point of interest |
| lon | number | Longitude (decimal degrees) of point of interest |
| last | integer | Limit to last N outlooks, 0 for all |
| day | integer | Day to query for, 1-8 |
| time | string or null | Optional specification for a valid timestamp to query outlooks for. This is either a ISO8601 timestamp or 'current' for now. |