Hotter temperatures will cause a slight enrichment of the mixture. If you originally jetted and tuned it in cooler weather, you could be seeing some signs of richness in these hot temps.
Start the bike and warm it up until fully warm.
Turn the large-headed idle speed screw in a little, until you achieve a slightly higher idle speed than you actually want.
Then turn the little bleed screw in and out, until you find the position that gives the fastest idle speed.
Then leave that right there, and turn the big-headed idle speed screw out to lower the idle to the desired idle speed. Choose a final idle speed which is fast enough to be even at idle, and not so low as to be on the edge of stalling out.
That should do you, if you have no underlying mechanical issues to sort out.