Can rainy weather cause migraines?

Ca be a trigger. Environmental factors such as atmospheric change can trigger a migraine attack in those susceptable. Perfumes, smoke, excessive heat/cold, hunger, dehydration, certain food types, sleep deprevation etc...Are common triggers as well. Keep your routines really routine to minimize attacks. Keep a headache log. Otc such as excedrine-migraine may help. If not, consult doc for eval. Good luck.
Probably not. Weather changes do seem to exacerbate some pain conditions but these are typically patients with arthritis. I don't think I have ever seen a headache patient who associates a change in weather with the development of headache.