Is it possible to take a train to Beijing during winter climax?

Tq mr Glen..I hope u are from China because i have more question to ask. I just want to confirm with anybody out there is is possible to take a train to Beijing during winter climax because from what i heard the bullet train trasportation will be closed in January..? And can i take a bus trasportation to go to Beijing at that time if bullet train services closed..? Hope someone out there will answering me..tq