People who want to participate in Alaska's biggest guessing contest have until Sunday to buy tickets for the Nenana Ice Classic.

Thousands of people each year pay to try to guess the exact date and time the ice will break up on the Tanana River in Nenana. Each guess costs a $2.50 ticket.

The most recent ice thickness measured about 35 inches, the Fairbanks Daily News-Miner newspaper (http://is.gd/JHuWqt) reported.

Each year, a clock is connected by cable to a wooden tripod anchored in the river ice about 300 feet from shore. When the ice breaks up and the tripod falls or moves, the cable tightens and stops the clock.

Cherrie Forness, manager of the Ice Classic, urged people not to wait until the deadline, which falls on Easter this year. "People are going to be running out, so don't wait until the last day," Forness said.

Ice Classic organizers last year ran out of tickets even though 300,000 were printed. Records were set for ticket sales and the size of the winning pot. Organizers this year printed 340,000 tickets.

The ice went out last year at 3:48 p.m. April 25. The record winning pot totaled $363,627 and was split among 25 tickets.

For this time of year, the 35 inch measurement is thinner than average. But it is close to the measurement of 36 inches on March 31 of last year.

The ice is not showing signs of weakness yet, Forness said.

"There has not been any water that we can see, of course," she said. "It's still solid from bank to bank, so it's still going to be a little bit."


Information from: Fairbanks (Alaska) Daily News-Miner, http://www.newsminer.com