I had this before the Japan quake yesterday (though I did not note it and didn't even correlate it at the moment, thinking it was the storm coming it) and I have had it before for Japan to Mariana's as I recall posting on Syzygy and EB about it in the past.
In the past I've had this symptom 24-72 hours before a quake occurs that is over a 6.0
In the past I've had this symptom 24-72 hours before a quake occurs that is over a 6.0