I don't really care where you live,
@GreySky - my guess would be you live either Down South where it is hot and humid, or maybe in a desert, which is hot and they SAY not humid though I wonder. Some people seem to really want to know.
If it were me, I'd run the thickest 20 I could find and call it a day. Or
@High Performance Lubricants passenger car motor oil, probably a 5W-20 MAYBE a 5W-30, although there doesnt much seem to be a point, unless you truly believe that most oils today are sub-optimal and only for fuel efficiency. There is a case made here every 2 days about this, though I have become one to go with a manufacturer recommendation, a la oil cap. Plenty cars had 5W-30 oil cap specified back in the day, now those cars use 20 or 30 so....