Dm
After loosing the trail, Ivan searches the area very carefully. The snow is now greatly impeding his efforts, but his keen eyes notice (Survival check: natural 20!) a very slight low point in some parts of the snow. Ivan manages points in the direction of the southeast and leads the party on.
After the snow has stopped for some time, the quarry's tracks become much easier to see in the freshly fallen snow and the tracking become somewhat elementary (no check necessary).
Three hours after you resume tracking, you reach the banks of the Klyazma river, a river flowing roughly east/west. The river is about 100-150 yards wide. It's not frozen over. You can see three small boats on the opposite side. Also, the forest continues on the other side.
You might be able to find a place upriver somewhere where fording is possible--the river has some islands that would make it easier. But none of you are sure.
Snow has stopped completely for some time, and the sky is reasonably clear.