The cheat rule is +15C in summer so yeah, that gets you about 36C. I guess that’s not really a rule per se...just following a dry adiabat down to the sfc. With everything right like downsloping, solar peak, lower evapotranspiration, dry surface fuels, etc BDL, FIT, MHT, etc can pull +17C, but we’ve had a bit of a wet stretch recently. I just hedge toward slightly dewier than the afternoon mid 50s progs and thermodynamics keeps it a relatively “cooler” 97° vs 101°. Maybe we’re debating 59° vs 60° dews again since it’s hot either way and the heat indices wouldn’t really be different in either scenario.