Hi! As of 8th January 2020, authorities have advised people not to travel to Shimla-Manali. Due to heavy snowfalls, over 582 roads in the state are blocked. The snow has made Manali roads impassible and many tourists have gotten stuck on the Kullu-Manali stretch for hours on end.
I'd suggest you to not to visit as of now, as may reasons Heavy snowfall, roadblocks, It could see a hassle to roam around as well, In short you would end up in trouble instead of having fun.
Yes snowfall is heavy, but it will be lifetime experience if you want to go to Rohtang also then it is not advisable but if you want to enjoy Manali it's best time as snow makes it more beautiful