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layout	title	description	date	sidebar	comments	sharing	footer	ha_category
page	Automation for rainy days	Basic example how to use weather conditions to set states	2015-10-08 19:05	true	false	true	true	Automation Examples

This requires a Dark Sky sensor with the condition precip_intensity that tells if it's raining or not. You could also experiment with other attributes such as cloud_cover.

Turn on a light in the living room when it starts raining, someone is home, and it's afternoon or later.

automation:
  alias: 'Rainy Day'

  trigger:
       - platform: state
         entity_id: sensor.precip_intensity
         state: 'rain'
       - platform: state
         entity_id: group.all_devices
         state: 'home'
       - platform: time
         after: '14:00'
         before: '23:00'

  condition: use_trigger_values

  action:
    service: light.turn_on
    entity_id: light.couch_lamp

And then of course turn off the lamp when it stops raining but only if it's within an hour before sunset.

automation 2:
  alias: 'Rain is over'
  trigger:
       - platform: state
         entity_id: sensor.precip_intensity
         state: 'None'
       - platform: sun
         event: 'sunset'
         offset: '-01:00:00'

  condition: use_trigger_values
  action:
    service: light.turn_off
    entity_id: light.couch_lamp