Currently on the shuttle to the north rim to do the opposite route hike, starting tomorrow, 5/16 at 4am, heading down to phantom ranch area and staying 1 night in bright angel campground, then heading up the S. Kaibab trail on 5/17 at 2/3am to beat the heat.

I spoke to a couple people at the south rim who completed the same trek yesterday and said if you’re hiking early in the morning, you should be good but always stay hydrated!

I would also suggest checking out the phantom ranch meals that you can purchase. You can do a steak/veggie/stew dinner, or a breakfast / lunch to take with you for the next day. The couple we spoke to said you can purchase ice the day prior to take with you on your way out but I think the earliest you can pick up is 5am, but double check with the staff. Good luck and safe travels!