So I was going through the weather tables in GM Law in developing a spreadsheet to calculate weather effects for my campaign and ran into an issue. Is the naming the average high and average low temperature columns just a mistake or were they actually thinking it should be the average? The rules as written(and I understand them) actually lists a temp one degree below the minimum high temp for the day. (the rules state to add the variation result to the "average high" and the variation result ranges from 1 to 60 depending on the roll and variation class)
So when converting weather charts from other products, should I use the average high from those products directly or try to convert them to a min high first?