“Some Like it Hot”-The Power Station
Hot in Herre by Nelly - it’s required to sing this when it’s freakin’ hot.
The Sun Is A Mass (of Incandescent Gas) - They Might Be Giants
When You’re Hot, You’re Hot - Jerry Reed
Some Like It Hot - Power Station
The Planet’s On Fire - Sammy Hagar
On Fire - Van Halen
Heat Wave, Martha and the Vandellas
Hot Fun in the Summertime, Sly and the Family Stone
Came in here to post that.
The world’s hottest song about heat.
“Steam Heat” from The Pajama Game, written by Adler and Ross.
“Hot Hot Hot!!!”-The Cure
“A Hundred And Ten in The Shade”-John Fogerty
Eternal Flame - the Bangles
The Desert Song - from the Operetta of the same name
Doors Light My Fire
You know why I didn’t include that song in my list (and a bunch of others)?
Because it isn’t about heat.
I ignored (or tried to ignore) songs that use “heat” or “fire” as a metaphor for lust, love, etc. I took the OP to actually want songs about physical heat, or, when it was somehat ambiguously phrased, could be reasonably interpreted that way.
ETA: YMMV of course.
Heat Wave - Irving Berlin, sung by Marilyn Monroe in There’s No Business Like Show Business and many others
A Horse With No Name, America
Billy Idol, Hot in the City.