They should be fine just keep the bin in the shade. Mine are outside. During the hot part of the season they tend to slow down due to the heat.

They were under an oak tree until we moved. Now they're on the back porch. If you keep them outside you will get visitors; both benign (black soldier fly larvae, springtails, pill bugs, etc.) and malignant (hungry coons, centipedes, fire ants & roaches). On those scorchers, I tend to put a small ice block in the bin to cool things down a little. In the winter, just insulate the bin with a few bales of hay and you're good to go.

I would recommend having at least 8 - 12 inches of bedding. Mine dive deep and I have had the problem of them going through the bin holes in the bottom in search of cooler soil.

Good luck.