[Harts]

Air temperature affects soil temperature, so there is a correlation. Our days are much shorter, meaning soil temps stay cooler longer into the morning before warming up in the afternoon, only to cool down again when the sun starts setting. This is a good reason to seed early in the Northeast instead of waiting until now or a week from now.

Yes, the grass will be slower growing but soil temps aren't so low that it's going to completely stop. We're not far away from that in the Northeast/Ontario though.

Someone else will likely chime in with a more scientific answer.