100 is not good as it induces hermies and slows down energy production among other things.

Try to stay under 90.
stickygreenlightsabr Reviewed by stickygreenlightsabr on . 100 Degrees Is 100 degrees F a deadly temperature or is it something that is ok? I know tomatoes thrive under average of 83, but my grow room as is gets from 86-100 depending on how I have stuff set. To make it stay around 86 I have to keep my window open at night, and leave my closet door open. I would do that but the bright HPS gets a tinsy bit annoying. Thanks for any info in advance. Rating: 5