Severe storm outlook (SPC) smart home integration, free and open source
NOAA Storm Prediction Center severe thunderstorm outlook for your house, today to day 3.
Published by guim31
- Devices
- Version 1.0.0
- Requires Gladys >=5.3.0
- ★ 0
The convective outlooks of the NOAA Storm Prediction Center (SPC) at your house, in Gladys: the severe thunderstorm risk category for today, tomorrow and the day after, and the tornado, hail and damaging wind probabilities of today and tomorrow. Scene triggers and a dashboard widget come with it.
Not an official warning service. The outlooks are forecasts of the days ahead. For watches and warnings in force, follow the National Weather Service (the National Weather Service integration brings them into Gladys), a NOAA Weather Radio and your local authorities.
Not affiliated with NOAA or the National Weather Service.
What you get
- One device per house of Gladys located in the contiguous United States.
- The SPC category of today, tomorrow and the day after: 0 (no severe risk, or general thunderstorms only), 1 Marginal, 2 Slight, 3 Enhanced, 4 Moderate, 5 High.
- The probability (%) of a tornado, of large hail (1 inch or more) and of damaging wind (58 mph or more) within 25 miles of the house, today and tomorrow; for the day after, the probability of any severe weather.
- The conditional intensity group (0 to 3) of each hazard: the higher it is, the more intense the storms could be (strong tornadoes, giant hail, destructive gusts). It replaced the hatched "significant" areas in 2026.
- A summary sentence, e.g. "Slight risk of severe storms today (tornado 5%, hail 15%, wind 15%); tomorrow: 3 · Enhanced".
- Three scene triggers and a dashboard widget.
Requirements
- Gladys Assistant 5.3.0 or later.
- The location of your house set in Gladys (Settings → Houses), in the contiguous United States. Alaska, Hawaii, Puerto Rico and the other countries are not covered by the SPC.
- Internet access from Gladys. No account and no key.
Configuration
Settings
| Setting | Default | What it does |
|---|---|---|
| Language of the feature names | French | Names of the features of new devices, language of the summary and of variables |
The integration asks for the location of your houses at installation: it reads their coordinates from Gladys and checks the SPC areas inside the container. Your location is never sent to anyone. Then open the Discover tab of the integration and create the device of your house. A house added or moved later shows up after a new scan in the Discover tab.
Devices
| Feature | Type | Value |
|---|---|---|
| Storm risk today / tomorrow / in 2 days | number | SPC category, 0 to 5 |
| Tornado / Hail / Wind probability | % | Today and tomorrow, within 25 miles |
| Severe storm probability in 2 days | % | Any severe weather, the day after tomorrow |
| … intensity group | number | Conditional intensity group of the hazard, 0 to 3 |
| Severe storm outlook | text | Summary sentence, in the language of the settings |
The categories are numbers (not the Gladys "risk" badge, which only knows four levels), so a scene condition such as "risk today ≥ 2" works. "Today" is the SPC convective day, from 12 UTC to 12 UTC the next morning. When the SPC does not answer, nothing is published: the last values simply age.
Dashboard widget
Severe storm outlook: for the house you choose (the first one otherwise), one line per day with its category, coloured after the SPC scale as far as the Gladys palette goes (green Marginal, yellow Slight and Enhanced, red Moderate and High, blue for general thunderstorms), a heading from Slight upwards, the tornado / hail / wind probabilities of today and tomorrow (with the highest intensity group, "CIG2"), the time of issue and a button to the SPC outlooks. The probabilities and the button each have a setting to hide them.
Scene triggers
- Severe storm risk reaches a category: a new outlook raises the category of a day to the chosen level (1 to 5) or above, once, when the level is crossed upwards. Filters: house, day (today, tomorrow, in 2 days).
- Severe storm risk upgraded: a new outlook raises the category of a day already forecast, whatever the level.
- Tornado probability reaches a level: the tornado probability of today or tomorrow reaches the chosen level (2 to 60%).
The same calendar day is followed from one outlook to the next: when the day 3 already said Enhanced, the day 2 that confirms it fires nothing. Variables: house, day, date, category and its name, summary; the previous category for an upgrade; the probability and the intensity group for a tornado. The very first outlooks read after the installation only set the reference: they fire nothing.
Scene examples
- When the risk of tomorrow reaches Slight, send "{{level_name}} risk of severe storms tomorrow" to the family.
- When the tornado probability of today reaches 10%, turn the hallway light orange and send a message.
- Every morning at 7, if the risk today is 3 or more, read the summary out loud.
Data sources, licence and quotas
- SPC convective outlooks, NOAA / National Weather Service, public domain (a work of the US government). Read every 15 minutes: eleven small GeoJSON files, with conditional requests, so a file unchanged since the last cycle costs a 304 answer with no content. The SPC issues the day 1 outlook five times a day, day 2 twice and day 3 once or twice.
Troubleshooting
- "No house of Gladys has a location": set the location of your house in Settings → Houses, then rescan in the Discover tab.
- "No house is in the contiguous United States": the SPC only covers the lower 48 states.
- The connection status says the outlooks cannot be read: the SPC site is unreachable. Nothing is published until it answers again, every 15 minutes.
Limits
- A forecast of the days ahead, not a warning: storms can form outside the areas drawn by the SPC.
- Developed without a severe weather day in progress: the tests use the real outlooks of 27 April 2026 (Moderate risk) and 7 November 2026. Feedback welcome.
- The probability of a hazard is given for 25 miles around the house, as the SPC defines it, not for the house itself.
Configuration settings
These are the settings Severe storm outlook (SPC) asks for in its configuration screen in Gladys.
| Setting | Type | Required | Description |
|---|---|---|---|
| Your house | section | No | The integration reads the location of your houses in Gladys and evaluates the SPC outlooks there, inside the container: the location never leaves Gladys. One device per house in the contiguous United States: create it in the Discover tab. |
| Sources and limits | section | No | Convective outlooks of the NOAA Storm Prediction Center (public domain), read every 15 minutes without an account. A forecast, not an official warning service: follow the warnings of the National Weather Service. Not affiliated with NOAA. |
| Language of the feature names | select | No | Names given to the features of new devices (Storm risk today…), and language of the summary and of the scene variables. |
How to install Severe storm outlook (SPC) in Gladys
- In Gladys, open Integrations: Severe storm outlook (SPC) appears in the catalog, next to the native integrations, with a community badge.
- Click Install. Gladys pulls the Docker image (
ghcr.io/guim31/gladys-spc:1.0.0), starts it in a sandbox isolated from the core, and generates the integration's interface (devices, discovery and configuration). - Open the Configuration screen of the integration, fill in the settings, and save.
- You can also install it directly from its repository URL: https://github.com/guim31/gladys-spc.
Severe storm outlook (SPC) requires Gladys >=5.3.0. The catalog inside Gladys refreshes every hour, so a new version becomes available at most one hour after its release.
Not running Gladys yet? It is free and open source: follow the installation guide to get started.
About external integrations
Severe storm outlook (SPC) is an external integration: a community integration packaged as a Docker container and published on GitHub, that Gladys installs in one click and runs in a sandbox isolated from its core. It is published and maintained by guim31, not by the Gladys core team.
- Browse all integrations, native and community
- Build and publish your own external integration
- Source code on GitHub — source of this documentation