Is your wimp factor not high too? Here's a novel concept: people respond differently to different weather conditions.
I can run a proper workout in over 95/high humidity. Heat doesn't bother me and my times are better in hot weather than cold, which is fortunate. Having said that, 23-25C is probably ideal.
Are you not a wimp for getting weaker and slowing down at the end of your runs in the heat? Why not fight through it? Ironic you're calling people wimps.