Terp evaporation temperatures might be published in vape sites. The most volatile are away at 21c/70f while the bulk of the flavour is leaving in the high 30s/100f. Some such as lemon hang on though. I'm guessing equatorial flavours will hold on the longest, because of natural selection. Most of us think we got everything we could want from weed grown around 25/77 and might think 21/70 weed tastes funny.