@marijnacht
Unfortunately Windy is not prepared to offer this mode. This is mainly due to the licensing agreements with ECMWF.
https://community.windy.com/topic/6601/offline-use-of-windy
However if you think about a solution to keep 3 to 5 days of weather displays in memory, that could be a good alternative, even if, in this case data, are not freshly updated.