How to use weather.get_forcasts in a helper?

1

I have a helper that I use to determine if I need to shut the shades on hot days.

I’ve read that get_forecast has been replaced by get_forecasts, but all the examples of using get_forecasts I can find are service calls…

{{
            state_attr('weather.openweathermap', 'forecast') | 
            selectattr('datetime', '>=', utcnow().isoformat()) | 
            selectattr('datetime', '<=',  (utcnow() + timedelta(days=1)).isoformat()) | 
            map(attribute='temperature') | list |max 
}}

How can I write a helper or template to call get_forecasts using openweathermap?

Am I correct in assuming that this mechanism to scan the forecast is being deprecated?

My attempts to RTFM have not enlightened me.
Thanks in advance

2

Yes, the forecast attribute has been deprecated and will be removed in 2024.3. So you have more than 3 months left to think about your needs and figure out how to use weather.get_forecasts and the response data.

At least for now, you can’t do it directly in a template helper, since they only support state-based sensors. It must be configured in YAML. Trigger-based template sensors now allow an action block that can be used to call the service and return the value.

Trigger-based handling of service response data

Forum Search Results: get_forecasts

3

My solution was to put the following into my configuration.yaml so I should always have a forecast available

template:
# My Weather Entities Daily
  - trigger:
    - platform: time_pattern
      hours: /1
    - platform: homeassistant
      event: start
    action:
      - service: weather.get_forecasts
        data:
          type: hourly
        target:
          entity_id: weather.openweathermap
        response_variable: hourly
    sensor:
      - name: Weather Forecast Hourly
        unique_id: weather_forecast_hourly
        icon: mdi:weather-cloudy
        state: "{{ hourly['weather.openweathermap'].forecast[0].condition }}"
        attributes:
          forecast: "{{ hourly['weather.openweathermap'].forecast }}"

Once this was in place then I could write template helpers like
Is it going to snow this evening:

{{
state_attr('sensor.weather_forecast_hourly', 'forecast')[1].condition in ("snowy")
}}

or what’s the max temp for the day:

{{
            state_attr('sensor.weather_forecast_hourly', 'forecast') | 
            selectattr('datetime', '>=', utcnow().isoformat()) | 
            selectattr('datetime', '<=',  (utcnow() + timedelta(days=1)).isoformat()) | 
            map(attribute='temperature') | list |max 
}}
3 Likes
4

thanks for your post, it helped me re-create my openweathermap based automation.
Technically speaking, (utcnow() + timedelta(days=1)).isoformat() limits the list to the next 24h, not to the current date.
This is what works for me:

selectattr('datetime','<=',(utcnow()+ timedelta(days=1)).replace(hour=0,minute=0, second=0))

also, openweathermap returns forecasts starting with date starting with now(), so I don’t think you need the first selectattr check.