The IBU confirmed today in a news release that IBU World Cup 4, which was scheduled to be held in Oberhof, Germany from January 7-10, will not be held there due to a lack of snow: http://www4.biathlonworld.com/en/press_releases.html/do/detail?presse=2674
According to the news release, all options for a relocation of the event are considered. The news release does not rule out the possibility of cancelling the event, but hopefully they will find another host.
A likely scenario would be to move World Cup 4 to Ruhpolding, which is the host of World Cup 5. Assuming they have snow, they may be in the best position to host an event on such short notice.