Maybe its allergies? Dust or pollen can clobber you. They usually prescribe a spray like Flonase and/or a pill like Zyrtec.
I once had sinus problems and, to my surprise a chiropractor massaged my face in a downward motion from top to bottom, down to the neck. It seemed to clear out the grit in the passages. That didn't work next time, though.
Someone recommended flushing out using saline mist through the nose to prevent them. I'd check that with a dr, wouldn't want to make a condition worse.