Concur. Doc 8186 used to have the scientific equation to calculate the lo-temp correction, which however could be used to calculate the hi-temps as well.
Just remember ISA is +15, the first visible effect for cold come around -5° C (ISA-20). Hence only at SL and 35+ the same deviation will be observed on a hot day.
For our summer destinations, a nice practice was to brief going for the PAPI profile earlier - when and where appropriate - if visual, to have the angle correct. One of the 'How to avoid +2g landings at LGIR' series. Flying precise DME/ALT table with a mis-indicating altimeter was just not giving helpful results.