MADISON, Wis. (AP) -- Fans of winter sports will have plenty of reasons to enjoy the outdoors this weekend.

Cross-country ski trails are open at most Wisconsin parks and forests, with conditions ranging from good to excellent.

Snowmobile trails are now open in about 30 of the state's 72 counties. Conditions range from fair to good.

The Wisconsin Department of Natural Resources says it's hard to say how thick ice cover is on northern lakes. Even though the weather has been cold, the ice on some lakes has been insulated by 5 to 10 inches of snow. That would prevent the ice from getting much thicker.

Lakes in southern Wisconsin are just starting to freeze over but many of the larger lakes are still open. The DNR urges anglers to be extra-cautious when venturing out.