As I write this, I am sipping nuun enhanced water - it is kind of warm outside.  You comments about listening to your body, etc are quite appropriate.

I would add - adjust your schedule.  Be an early riser and get going pre dawn.  You have until about 9 AM  before it really heats up.  In our SW deserts, it is often surprisingly chilly early in the morning - and delightful!!.  There is a reason for midday siestas, with resumption of work toward evening.

if it is really hot, do all your hiking and heavy work after the sun sets.

I favor a cotton full brim hat, dripping wet, and renewed as often as possible.  Wetting you shirt works as well.

When it is really hot, I can easily drink a gallon a day, besides liquid in fruits, etc.  Ration sweat, not water.  Slow down if you have to and learn to recognize the symptoms of dehydration.

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