I hate to say it, but usually, when getting headaches and moving to WA coincide...there are usually 2 culprits:
1) Sinus infections from all the molds in the air (we have more molds then all but 2 of the rain forests in the world)
2) The huge amount of flat light...aka all the white light from the white sky from the grey and white clouds which only gets made worse when it rains, because then all the light reflects up from the streets.
The light is easy to fix with sunglasses... although since we so rarely have SUN & blue skies, you may feel silly wearing them, or just plain forget.
The sinus infections are a LOT harder to deal with. The kind of mold inspired sinus infections we all get, tend to not be the drippy kind...and tend to NOT be the screaming-meemee-omigod-if-i-bend-over-my-head-will-explode kind...just this constant aching pressure. If you're like me, and your physiology means that that pressure transfers to your facial or trigeminal nerve...it will cause your shoulders and neck to get tighter and tighter, and then impinge on of of the ganglia in your spine, and then cause migraines. <grinning> I'm actually one of several people I know of that massage keeps most migraines from happening, but that if I start feeling one coming on I can kick it's butt by taking a pseudoephidrine instead of the big-guns that migraines usually require. (Sudefed from behind the Rx counter, not Sudefed PE)
Of course, grinding your teeth falls right into making that whole situation worse, because that messes with the same nerves that sinus infections mess with.
So try some sunglasses, worn religiously for a week... and either a decongestant or a trip to the doctor to. If you try the decongestant... it's not like having a cold. One dose or half a dose usually relieves the pressure well enough for your immune system to be able to work more effectively on the infection. Sometime you might have to 1/2 dose or dose once a day for a few days... but in my experience, and in talking with others... that usually takes care of it for the month. And then the mold reasserts itself and you have to start over.
Best of Luck,
headaches are miserable