Tired of weather sneaking up on me
Even with the 5-day weather forecast displayed right in my face on my bathroom mirror, I am ashamed to admit how many times a friend or colleague mentions an upcoming storm and I am completely unaware. Most recently this morning, in a meeting with the director of my team when he mentioned hoping his flight will beat the storm. Obviously, a simple forecast just isn’t enough to grasp the scale of how nature intends to fuck with your plans this week.
Enter: National Weather Service API
The National Weather Service offers a free API for retrieving active alerts and alerts for specific ranges in time. Unfortunately, this isn’t integrated directly into Home-Assistant – thankfully, there’s a huge community around Home-Assistant and I was able to locate a project by Mcaminiti that integrated with the NWS Api:
His integration does exactly what it needs to do, but I felt a few aspects could be improved upon:
- Requires the
zone_idretrieved manually from a list on the NWS website - Only currently active alerts are consumed
- The sensor’s state is the number of alerts, with categories broken out in the entity’s attributes
Given my tagline: Engineering only the highest quality laziness for over 20 years, is it any surprise I don’t want to manually retrieve some zone_id from a giant list of states, counties, regions, etc. Reading through the NWS API Specification for the /alerts endpoint, listed in the parameters is a property named point – which accepts latitude,longitude as a string. In Home-Assistant, many entities have latitude and longitude: zones, device_trackers, even the core configuration. So, there is absolutely no reason to go looking for a zone_id that may or may not even be correct!
Some more interesting parameters in the /alerts endpoint are start and end. The API Specification doesn’t do a great job of defining the format for start and end, but after some digging, it accepts ISO-8601 with a timezone offset, i.e. 2019-11-26T01:08:50.890262-07:00 – don’t forget the timezone offset or you will get an HTTP 400 response! By utilizing these parameters, you can get weather alerts for the future, not just the active weather alerts.
Having the number of active alerts be the sensor’s state has its use case, but for me, displaying the most recent weather alert is of much greater use for my needs. My use case is: if there is active or upcoming severe weather, I want that displayed in large letters in my mirror – preventing any more instances of surprise weather.
The Improved NWS Warnings Integration
Built as a sensor platform allows any number of NWS Warning sensors. I set up the configuration as such:
sensor:
- platform: nws_warnings
name: NWS Warnings
icon: mdi:alert
severity:
- extreme
- severe
message_type:
- alert
- update
zone: zone.home
forecast_days: 3Here, you can specify the severity of the weather alert, whether you wish to receive updates along with alerts and how far in the future you with to retrieve weather reports. If zone is provided, the request uses the zone‘s latitude and longitude as the point of reference when retrieving weather reports. Alternatively, you can specify a location instead of zone, with latitude and longitude – in case there is no zone entity for which you want to receive weather updates.
Including forecast_days will retrieve any weather reports from the start of the current day, to n-days layter (where n is the value of forecast_days); this allows for advanced warning of sever/inclement weather. Omiting forecast_days will only retrieve active weather reports.
Putting it all together
Now that we have our integration to the NWS alert API, it’s time to let my household aware of any severe/inclement weather in the coming days. I created a Conditional Card on the front-end, if there NWS Alert has something to report, it shows at the top of the MagicMirror interface, otherwise it is completely removed from the MagicMirror interface:
