Just my quick and dirty way of integrating the Data of wassertemperatur.org into Home Assistant, in my case the temperature of the Alster.
I don’t know if it’s accurate, but it is kinda nice to have if you want to go out for water sports
Just paste the following lines into your sensor.yaml:
- platform: scrape
resource: http://www.wassertemperatur.org/alster/
select: ".entry-content > h2:nth-child(6) > span:nth-child(1)"
name: Alstertemperatur
unit_of_measurement: "°C"
value_template: '{{ value | replace (" °C", "") | float }}'
scan_interval: 43200