Ya 13 days is pretty long even for me! It's A LOT of food to carry, the backpacks were definitely heavy at the start. Fresh clean water is fairly abundant in the High Sierra so we usually never have to carry more than 1 or 2 liters at a time. Besides the quick little snow the first night and the really cold nights towards the end we really were spoiled with nice weather on this trip. That's not usually the case in the Sierras. The weather up there can be really unpredictable, sun can be shining, clear blue sky, then clouds come in, huge thunderstorm hits, and just dumps rain and hail, and then by the afternoon the suns back out and the clouds completely disappear. You just never know up there, but we got lucky!