My son used to do some personal training in Arizona and told me to drink two bottles of water at the first sign of a headache when it's warm or humid out. I didn't tell him why at my age that's not a good idea. I have tried a full 16 oz all at once - not his 32, and it helped wonderfully, but my headaches are not migraines.
We need to move over to the July thread and let Cindy close this one.