Running Firebreak 5, trail #14 in the Tillamook State Forest just East of Tillamook, Oregon, in late January poses very challenging, very wet and very slick muddy conditions that make this trail very challenging but very fun too.
This is a Jeep badge of honor trail so if ya want to know what the worst conditions look like, here ya go. Rain, Mud, snow, we hit it all on this trail. Jeep badges of Honor App rates this trail a 47 on a ten scale and if it is wet or raining, go ahead and put that rating to the max because it is slick clay with big rocks, up hill, that give it that rating.
The trail jumps right to it with the most challenging section, seen in this video, are on the lower portions of this trail. Be aware that in winter, the top section can hold snow. We were there a week after a big storm and snow was on the ground in places.

Rig info:
2015 Jeep Rubicon Unlimited with 34" tires and 2 inch wheel spacers on a 3 inch lift with full bell armor protection.