New Hampshire Fish and Game Department officials are warning that this winter's uneven temperatures and high winds have affected ice formation, particularly on the state's larger lakes.

Fish and Game is urging those heading out onto the ice to exercise caution as they do so. A large number of anglers are expected to head out onto the state's lakes and ponds this weekend to participate in the Meredith Rotary Ice Fishing Derby. A recent aerial survey of Lake Winnipesaukee by the N.H. Civil Air Patrol revealed treacherous ice conditions on some parts of the big lake, including an area of open water near Welch Island.

"Caution is in order for those going out onto the ice, especially on the large lakes," said Fish and Game Lt. James Goss. "Don't let the cold temperatures fool you - some areas that have traditionally been safe for ice anglers and other outdoor recreationists are not safe this year. We are urging people to check the ice thickness for yourself before you go out onto any frozen waterbody."

Because of the unpredictable ice conditions, it is not advisable to drive vehicles onto the ice, Goss said.