The free tier "One Call API" is all that's required, you will need to subscribe and grab your API key.
- openweathermap:
label: Kyiv #optional
latitude: 50.449684
longitude: 30.525026
units: metric # or imperial
provider: openweathermap
apiKey: youropenweathermapkey # required only if not using provider, this reveals api key in requests
cache: 5 # Time in minutes to cache API responses, to stay within limits
format: # optional, Intl.NumberFormat options
maximumFractionDigits: 1
You can optionally not pass a latitude and longitude and the widget will use your current location (requires a secure context, eg. HTTPS).