If others can remember their flights, perhaps we can see if there is a trend on certain A/C.

I've had a 10 out of 10 on the pain scale only once Dec. 23, 1998. An AA F-100 going ORD-YOW, heading home for X-Mas. Nothing until about 8,000 feet, than it hit like a sledge hammer between my eyes. I had my head against the window with tears streaming uncontrollably down my face. I have never felt anything like it. I had the worst headache until the next morning, and was dizzy for most of the hour long ride home. Also for interest sake, just want to throw in the wether. On this trip, I left MIA at 7PM, where it was 80F and humid, ORD was about 10F, while YOW was -40F and cold/dry around midnight. Does a 120 degree temperature swing in 5 hours contribute to this?????

I've had a few other times where I could feel it coming on, but very mild at the least. These other few times, I pressed my finger between my eye-brows and felt the pain. But didn't feel anything else other than that.