Richiesmom: A positive opk means your LH is surging. You should expect ovulation in 24-36 hours after it. and then the temp spike the day after you O. For example, positive opk on cd 16, temp rise on cd 18 which means O on cd 17.
It does happen where ovulation happens on the same day as a positive opk but it's usually the next day.
So yesterday was a positive OPK, today you will likely ovulate, and tomorrow you should see a temp spike. Also note, the temp spike doesn't have to be big and apps like fertility friend require 3 sustained higher temps to predict O.