Historic Accuweather Temperature

Am I right in thinking that if I want to see historic accuweather temperature data on a chart I need to create a manual sensor to extract it because it is a state attribute?

If I create one will history only be available from when I do so or will historic values be available?

If you create a template sensor then you will only see the values from when the configuration was reloaded.
If you need from before that, then you need to get an API that you can get the data from

Depending on where you are in the sensor, if it is e.g. under the forecast attribut then HA does not keep history. I opened a case on it which was rejected / not-in-view.
So yes, if you want to trak on attributes, you might need to create a sensor on it…sad but …