Ambient Air temp & draining a pool

I need to partial drain a pool (chemicals out of whack, high CH/TDS), and was wondering at what point the window of opportunity to safely drain the pool, with out harming(cracking, peeling) of plaster due to high ambient temps.

We are currently in the 90's+, and I am wanting to do a partial drain.
Any experts out there willing to assist and or comment on how best too
perform the drain, or am I going to have to wait till fall/winter when temps are much lower ?

Thanks.

Chris