I know it's a late answer. But I recently had the same question. During my research I found this site:

https://dev.meteostat.net/

I know it's a late answer. But I recently had the same question. During my research I found this site:

Meteostat

They describe themself as

Meteostat is an open platform which provides free access to historical weather and climate data.

There's a own python library and a JSON API available (2022-07-18).

I found that for my locations of interest the last few months (~4) aren't available.

For all the ones looking for a simple and free way to get historical weather data this is the best source I found.