Is constant yawning the day before a migraine actually a warning sign?

My partner clocked it before I did. He asked if I was knackered halfway through a film because I'd yawned about a dozen times. I wasn't, I'd slept fine. Woke up the next morning with a full attack. After that I started paying attention and the pattern was almost embarrassingly obvious. Five, six, seven yawns inside twenty minutes when nothing else was off. Now when it kicks in I just plan for a rough morning, get to bed early, and have rizatriptan on the nightstand instead of in the kitchen. Hasn't stopped the attacks but the time-to-relief is loads better. Has anyone else got a prodrome that someone close to them spotted before they did?