SMHI

The SMHI integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] brings weather forecasts and fire risk forecasts from SMHI, the Swedish Meteorological and Hydrological Institute, into Home Assistant. Use it to show the weather and forecasts for your home on your dashboard, or to get notified when thunder or a high fire risk is expected.

The integration works for locations in and near Sweden and does not need an account or an API key. Each location you add becomes its own entry in Home Assistant, with a weather entity and sensors for that location.

Use cases

• Show the current weather and the daily or hourly forecast for your home on your dashboard.
• Get a notification when thunder is likely, so you have time to bring in garden furniture or unplug sensitive electronics.
• Check the fire risk before you light a barbecue or a campfire, or get notified when the risk is high.
• Follow the weather at a second location, such as a summer house, by adding it as a separate entry.

Configuration

To add the SMHI service to your Home Assistant instance, use this My button:

If you keep the map pin on your Home Assistant home location, the entry is named Home. For any other location, the entry is named Weather followed by the coordinates. To add more locations, add the integration again.

Reconfiguration

You can move an entry to a different location without removing the integration. Your entities and their history are kept.

The entry keeps its name after you move it. If the name no longer fits the new location, rename the entry.

1. Go to Settings > Devices & services and select the SMHI integration.
2. Next to the entry, select the three dots menu, then select Reconfigure.
3. Select the new Location on the map, and select Submit.

Supported functionality

The SMHI integration provides the following entities for each location.

Weather

• Weather
  • Description: The current weather and forecasts for the location. Use it with the weather forecast card on your dashboard, or with the weather.get_forecasts action in automations and scripts.
  • Current values: Condition, temperature, humidity, pressure, wind speed, wind gust speed, wind bearing, visibility, and cloud coverage.
  • Forecasts: Daily, hourly, and twice-daily (day and night).
  • Remarks: The entity is named after the entry, and its entity ID starts with weather.smhi_. For example, weather.smhi_home.
  • Attributes:
    • Thunder probability: The probability of thunder, in percent.

Weather sensors

• Thunder probability
  • Description: The probability of thunder.
  • Unit: %
• Precipitation category
  • Description: The type of precipitation expected.
  • Options: No precipitation, Rain, Thunderstorm, Freezing rain, Mixed/ice, Snow, Wet snow, Mixture of rain and snow, Ice pellets, Graupel, Hail, Drizzle, Freezing drizzle
• Frozen precipitation
  • Description: How much of the precipitation falls in frozen form, such as snow or ice.
  • Unit: %
• Total cloud coverage
  • Description: The mean value of total cloud cover.
  • Unit: %
  • Remarks: Disabled by default.
• Low cloud coverage
  • Description: The mean value of low-level cloud cover.
  • Unit: %
  • Remarks: Disabled by default.
• Medium cloud coverage
  • Description: The mean value of medium-level cloud cover.
  • Unit: %
  • Remarks: Disabled by default.
• High cloud coverage
  • Description: The mean value of high-level cloud cover.
  • Unit: %
  • Remarks: Disabled by default.

Fire risk sensors

All fire risk sensors are disabled by default. To use them, enable the sensors you need.

• FWI index
  • Description: The fire weather index (FWI) as a risk level.
  • Options: Very low risk, Low risk, Moderate risk, High risk, Very high risk, Extremely high risk
• Fire weather index
  • Description: The fire weather index (FWI) as a number. A higher value means a higher risk of fire.
• Initial spread index
  • Description: The expected rate of fire spread (ISI).
• Build up index
  • Description: The total amount of fuel available for a fire (BUI).
• Fine fuel moisture code
  • Description: The moisture content in dead, fine fuels on the ground (FFMC).
• Duff moisture code
  • Description: The moisture content in loosely compacted organic layers of moderate depth (DMC).
• Drought code
  • Description: The moisture content in deep, compact organic layers (DC).
• Highest grass fire risk
  • Description: The highest grass fire risk, according to the SMHI grass fire model.
  • Options: Snow cover, Grass fire season over, Low, Moderate, High, Very high
• Potential rate of spread
  • Description: How fast a fire can spread in uncut and ungrazed natural grass.
  • Unit: m/min
• Fuel drying
  • Description: How much water is available in the forest fuel.
  • Options: Very wet, Wet, Moderately wet, Dry, Very dry, Extremely dry

SMHI automation examples

You can use the SMHI sensors in automations, for example to get a warning before thunder or when the fire risk is high.

Automation: Get notified when thunder is likely

This automation sends a notification to your phone when the probability of thunder rises above 50%.

• Trigger: Entity: Numeric state
  • Target: Home Thunder probability (sensor.home_thunder_probability)
  • Above: 50
• Action: Send a notification message
  • Target: My Device (notify.my_device)

alias: "Notify when thunder is likely"
triggers:
  - trigger: numeric_state
    entity_id: sensor.home_thunder_probability
    above: 50
actions:
  - action: notify.send_message
    target:
      entity_id: notify.my_device
    data:
      message: >
        SMHI forecasts a high probability of thunder.

Automation: Get notified when the fire risk is high

This automation sends a notification to your phone when the fire risk becomes high, very high, or extremely high. It uses the FWI index sensor, which is disabled by default. Enable it before you create the automation.

• Trigger: Entity: State
  • Target: Home FWI index (sensor.home_fwi_index)
  • To: High risk, Very high risk, Extremely high risk
• Action: Send a notification message
  • Target: My Device (notify.my_device)

alias: "Notify when the fire risk is high"
triggers:
  - trigger: state
    entity_id: sensor.home_fwi_index
    to:
      - high
      - very_high
      - extreme
actions:
  - action: notify.send_message
    target:
      entity_id: notify.my_device
    data:
      message: >
        SMHI reports a high fire risk. Avoid open fires and barbecues.

Data updates

The integration pollsData polling is the process of querying a device or service at regular intervals to check for updates or retrieve data. By defining a custom polling interval, you can control how frequently your system checks for new data, which can help optimize performance and reduce unnecessary network traffic. [Learn more] SMHI for new weather forecasts and fire risk forecasts every 31 minutes. The weather.get_forecasts action uses the forecast data that is already loaded, so it does not send extra requests to SMHI.

The data comes from the SMHI open data API. SMHI provides the data for free under the Creative Commons Attribution 4.0 International license.

Known limitations

• Only locations within the SMHI forecast area can be added. This area covers Sweden and the areas close to it.
• The current weather and the weather sensors use the first hour of the latest SMHI forecast. The fire risk sensors show today’s SMHI fire risk forecast. None of these values are weather-station measurements.
• The weather entity never reports the conditions hail, windy, or exceptional, because the SMHI forecast does not provide them.
• The fire risk sensors are most useful during the fire season. Outside the season, some of them can show values like Snow cover or Grass fire season over, or have no value at all.
• Each entry covers one location. To follow several locations, add the integration once for each location.

Troubleshooting

Removing the integration

This integration follows standard integration removal. No extra steps are required.

To remove an integration instance from Home Assistant

1. Go to Settings > Devices & services and select the integration card.
2. Next to the entry you want to remove, select the three dots menu. Then, select Delete.
   • Depending on the integration, the entries are listed under one of the following headings:
     • Devices
     • Hubs
     • Services
     • Integration entries
3. To confirm, select Delete.
   • Home Assistant also deletes the devices and entities of the entry.
4. If Home Assistant asks you to restart, restart Home Assistant.
5. If Home Assistant asks whether to also delete the application credentials, select Remove or Keep.
   • If you keep them, Home Assistant uses them automatically when you add the integration again.
   • To delete them later, refer to Deleting application credentials.