I read this new thing recently, and I liked it

IFR with 1 comm radio

I have always flown IFR with a 2 comm radio aircraft and now I am in a ship with only 1 comm radio.  If I am on with ATC and I need to get the weather for the airport that I am landing at, how do I get the weather?

Do I ask ATC for the weather or how do I ask for permission to switch frequency to get the weather?  What communication format is used when I’m back on with ATC?

Also, am I correct in assuming that when ATC says, “advise when you have the weather at …” that this is NOT permission to dump them to get it?

Thank you for the help