Can this be done without extra sensor?

Configuration
1

I am trying the following automation where if humidity of the bathroom is above 12 of the outdoor humidity to get a notification

Should I make a sensor with the difference of these 2 sensors or I could do it without?

# Bathroom Humidity  **********************************************************
- id: Bathroom Humidity
  alias: Bathroom Humidity
  trigger:
    platform: template
    value_template: "{{states.sensor.bath_temp.state|round|int-states.sensor.outdoor_temperature.state|round|int}}"
    above: 12
  action:
    - service: notify.mobile_app_sm_g955f
      data:
        message: "Μπανιο υψηλή Υγρασια-Ανοιξε Παράθυρο"
        data:
            color: '#2DF56D'
            ledColor: "blue"
2 
  trigger:
    platform: template
    value_template: "{{states('sensor.bath_temp')|float - states('sensor.outdoor_temperature')|float > 12}}"
  action:
...
1 Like
3

I was almost certain that I have seen something similar… thank you!
I will delete my sensor and keep this.