It’s really interesting when you look into it. I hate to derail this thread but forgive me for just posted a few graphs. Look at the high’s and low’s and the dates. Exactly when the front came through. Although keep in mind If a reefer was farther north, his pH changed first.Thanks, I had not seen that.
Wind has a huge effect on air turnover in homes. I see it also in radon measurements that I've been taking.
Interestingly, so does the difference between indoor and outdoor temp. A higher temp inside drives more air flow into a home at the bottom and out the top, or the other way around when outside is hot. The result can be a change in pH.