On Jan. 17, the airport recorded 2.4 inches of snow, and "Brenda in Baltimore" and her husband had terrible headaches: "We ... were wondering about the connection [between] weather and headaches. Could it be the barometric pressure?" Could be. Science can't fully explain it, but there is strong anecdotal evidence linking weather changes to headache and arthritis pain. Barometers measure air pressure, which dropped sharply on the 17th as clear skies changed to snow and rain.