Hi Naseeb :) Don't go by what others are saying, I did Kedarkantha trek in December and it was absolutely stunning! If you want to feel the thrill that comes with trekking in the snow, go on a Kedarkantha trek in December. You can check out Indiahikes/Bikat adventures - they are organizing it for Dec, The trails are open, nothing is closed. You'll be amazed by the views - trust me! Just go for it!
Yes, completely unless you have any health issues.
infact this is the peak season for Kedarkantha trek, you will find many people on the way. However, I advise you to book it with a group and not do it alone.
No it's not
as the temperatures drop to a very low level
it's not safe to travel there in December.
You can postpone the trip during the end of summer when the weather conditions are slightly moderate.
No one will advice you to do so , and more importantly there are various traveling restrictions in these parts during the October end to Feb end period due to adverse and uncertain climatic conditions.