You have Already Determined What Time It is
In some regions, cold weather can throw off school schedules, and the same thing can happen in other regions, but with milder temperatures. When it comes to the weather, everyone has their own individual preferences. On the other hand, each of these extremes pose a significant risk to human life.
In the same way that kids on the east coast might have to head home early on a snow day, students on the west coast might have to be careful about how much water they drink if the temperature is very high. You wouldn’t really expect your teacher to give you a chance to get some water every once in a while, would you?