FAIRBANKS — It’s one of the first signs of spring in the sun-starved Interior.

Tickets for the 97th annual Nenana Ice Classic go on sale today around the state, including at more than 50 vendors in Fairbanks and North Pole.

The Ice Classic’s bright red ticket cans and tickets were delivered to stores, bars and gas stations in Fairbanks earlier this week, manager Cherrie Forness said.

“Come and get ’em,” she said.

Starting today, people can plunk down $2.50 per ticket to guess the exact day and time — down to the minute — that the ice will go out on the Tanana River in Nenana. Guesses are dropped in the red ticket cans, which are collected in April to be sorted. The deadline to buy tickets is midnight April 5.

Started in 1917 by a group of bored railroad engineers waiting out the winter in Nenana before going back to work in the spring, the guessing game is one the oldest traditions in Alaska and is the closest thing to a lottery that Alaska has.

Each year, thousands of Alaskans buy a ticket or tickets to guess when the ice will go out, as determined by a clock wired to a wooden tripod that is set up on the river ice. When the tripod moves or falls as the result of the ice moving, the clock stops.

Approximately half the ticket sales go into a jackpot that is split by the winning ticket holders — there is usually more than one — while the rest goes to pay for event itself and to support different nonprofit groups in Nenana, the small town on the Parks Highway 55 miles southwest of Fairbanks.

Last year’s jackpot was a record $350,000 and it was a winner-take-all affair. Tom Waters, of Fairbanks, was the lone winner when the ice went out on April 23 at 7:39 p.m. Alaska Standard Time. Incredibly, it was the third time that Waters won the event.

“I hope our sales are good and we can have a good jackpot like last year,” Forness said.

“We’ve had a couple of good years in a row and we’re hoping this is another good one.”

This year’s first ice measurement was taken on Jan. 16, and it was 41 inches thick, Forness said. That’s thicker than it was at this time the last two years but thinner than it was the three prior years.

Depending on the year, the ice thickness typically peaks between 40 and 55 inches sometime in mid-March before beginning to thin and rot, Forness said.

How quickly it does both depends more on the weather in April than February, she said.

Asked to predict when the ice will go out this year, Forness said “It’s hard to say at this point. It’s going to get thicker, I know that.”

The earliest breakups on record were April 20 in 1946 and 1998, while the latest was May 20 in 1964.

The most common breakup dates are April 29 and 30. The ice has gone out nine times on both those dates.

Contact staff writer Tim Mowry at 459-7587.

Ice Thickness

The first ice measurement for the Nenana Ice Classic was taken Jan. 16. The Tanana River ice in Nenana measured 41 inches. Here are early ice measurements the previous five years.

2012 — 23’’ on Jan. 12

2011 — 38’’ on Feb. 8

2010 — 44’’ on Feb. 3

2009 — 42.5’’ on Feb. 5

2008 — 44.0’’ on Jan. 21

For a complete list of ticket vendors in the Interior and around the state, as well as other information on the Nenana Ice Classic, go to www.nenana