Hello David,
It looks like at 12:30 on 7th November, the contents of the November data file were replaced with the data from another month - this month had 31 days in it so possibly October. Your file contains all the other month data and the November data from 12:30 on the 7th onwards (hence the very noisy graphs and weird stats). The data from 1st November 00:01 to 12:29 on the 7th has been replaced by the data from the other month.
I have attached the edited file which removes all the other month data leaving just the November data from 12:30 7th November onwards.
I would suggest quitting WeatherCat, remove the 11_WeatherCatData.cat and 11_WeatherCatData.cat.hrs files from the 2015 folder and then add this one.
Next, run disk utility over your disk as it's possibly a directory/cross link issue with the filing system. It would also be worth checking the October data file as it may be similarly affected.
Once the filing system is checked and OK'd, run WeatherCat - you should have correct data (and stats) for November from 7th onwards.
