Went on a long scenic tour of Yorks coast and moors on a very hot day a couple of years ago. Decided to land out at a favourite grass strip on the way home to have a drink as I was parched. Let down into the overhead, got the runway and wind and couldn't work out which way I was supposed to go. Eventually saw another a/c in cct and followed it. A/c I was following promptly disappeared right in front of me.
Made a very shaky landing on what I thought was the right runway and poured myself out of the cockpit breathing heavily.
Dehydration is a killer. Always carry a bottle of water/non fizzy pop on a hot day. Gatorade is very good.