Eh, there's some problem with calculating the number of days since the previous winter solstice. Probably a small offset getting introduced somewhere because the values seem too high across the board (e.g. number of days since previous winter being over 365.2421 days in some cases).

I think it might be because I'm judging based on the start of the day and not accounting for winter starting between midnight and the high temperature time, but I don't want to fix that now.