I, for one, find that sunglasses don't help in that situation. At any rate, the ones I have don't. Maybe there simply aren't any sunglasses that can help when Old Sol is directly in one's face. A welder's helmet might help with the sunshine problem, but hydration might be impossible while wearing it.
For that reason I welcome overcast skies at this time of year. Squinting and struggling to see without having the sunlight blind me is tiring. It's unnerving, too, because I always have the feeling that I'm about to ride right into something or someone.
It looks as though I'll get my wish for overcast skies in the coming days. There's a pretty good chance that it will rain. Then I'll gripe about the rain! I'm like King Derwin in the Dr. Seuss story about the oobleck.
So let the clouds come, but Rain, rain, go away.