No pointers involved, so I guess sometimes something goes wrong in float to char conversion.

I tried to search gcc buglist, but couldn't find this one reported - so it might also be somewhat system / hardware dependent, or anything like that.

So, in any case, I'm happy that I found it, and that there is an easy way out. It is just my old-school way of "never reserve more memory you are actually going to need" - but since we are no more living the times of Commodore 64, an array with 365 elements isn't that big. So no need to worry, if the array contains a variable of type "int", but actually only uses less than 8 bits to store the values.

OK. Now as I have a base temperature for each day, I'm going to make it so that hour by hour the base temperature is altered by other variables. Like, if it is clear sky with sunlight, it increases the temperature. And a strong wind from north will decrease the temperature. And things like that.

It already tracks ice and snow thickness, so eventually we are going to see summer / winter transitions being more gradual and unpredictable.