Geocoded Weather Warnings

I’ve been searching around for a while for a way to make home assistant aware of severe weather alerts (Severe Thunderstorm Warnings, Tornado Warnings, etc.) The best I’ve found is the Alerts from the US National Weather Service (nws_alerts) custom component. It works well, but the alerts are not very granular since it’s pulling them based on the NWS zones, which include a relatively large geographic area.

I would love to see an integration with HA to query weather alert polygons and compare that with the lat/long defined in home assistant. That would provide hyper-local weather alerting, preventing false alarms. The alert polygons could be displayed in the UI along with the warning text and radar imagery.

I’ve tried to do some research on this, but I am quickly finding this outside of my capability.

I believe that the US NWS publishes geospatial impact area data with its alerts as most weather monitoring companies have integrated this into their products (weather radar apps etc.)

Here are a couple of references I have found:

I’m pretty sure that many of the commercial products are getting their weather data from an aggregator like Allison House, but using a service like that might become cost-prohibitive for home use.

I like this idea.

The radar images from NWS already have the warning polygons overlayed. Check out my custom component nwsradar. The readme example has some flood warnings boxes. So all that is left is to get the warnings filtered by the polygon.

To get alerts, there are a few custom components out there. This is also one planned for the built-in NWS integration, but none currently have the functionality you want that I’m aware of. I’m willing to build this filtering functionality into the built in integration, but it isn’t my highest priority. I would welcome someone writing a PR for pynws to do it.

Warnings include the polygon shape in the alert, but only for some types of alerts. See this one. So there could be an additional filter based on the lat/lon being inside/outside the polygon. If no polygon is provided then it also keeps the alert.

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what about the GDACS integration?

To my knowledge, GDACS only has events like cyclones and volcanoes which have large impact. NWS provides alerts for things like thunderstorms, hail, and tornadoes, all of which can be very local.

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@MatthewFlamm- Thanks for taking a look at this. I think you are on the right track. As in the example alert you linked, I believe that all “severe alerts” include polygons now (advisories, watches, and warnings.) But, I agree that if a polygon is not present, it can fall back to the Zone IDs.

I looked at some of your work, and you are definitely further down the path then I am. I would be happy to collaborate on the front-end design/functionality side, but unfortunately, the back end is outside of my league.

@DavidFW1960- GDACS is excellent, but it does not cover local severe weather alerts to the detail that the NWS provides. I sometimes see GDACS alerts for floods, for example, when it impacts a large geographic area.

What frontend work do you think is needed?