Take a baby's higher sensitivity to nighttime temperature changes into account.
Twice now, our inadvertent temperature-related actions upset the kid enough to wake her up much earlier than normal. Once, we turned the A/C down before bed, as we always did. But it turned out to get too stuffy for a 2-month old who couldn't throw off her snugly swaddled blanket.
Then this morning, the unseasonal coolness that had us pulling the blanket around us woke up the kid who's mastered kicking off her blanket--but not pulling it back on.