They've been skating outdoors since New Year's Day on Bloomington's 13 rinks. Skaters have been carving up 10 rinks since Monday in St. Louis Park.

But Minneapolis? Rinks are open in only three parks of a planned 22. Minnetonka's seven rinks and all six in Hopkins have yet to open. St. Paul is somewhere in between with four refrigerated and five nonrefrigated rinks at seven parks open as of Friday. That's one-third of the rinks it hoped to open by now.

One skater who's getting antsy is Connor Schaefer, who played youth hockey in Falcon Heights and then indoor intramural hockey at the University of Minnesota. Now grad school studies have pushed aside intramurals, leaving only this time between semesters for pickup hockey. "That's why I was hoping this winter break it would be ready," he said.

The laggards among cities blame unseasonable warmth for their lack of ice. But all are dealt the same weather, give or take a couple of degrees. One factor that separates cities in how fast they're opening outdoor ice appears to be how gung-ho they are about the job.

Bloomington has had ice all month because of a four-day blitz that began the Monday after Christmas.

That meant crews starting work as early as 3 a.m. to take advantage of overnight lows. The snowfall a day after Christmas was helpful because trucks could pack it to a crust over the barely frozen ground to increase the seal for subsequent flooding, according to Dave Hanson, an assistant maintenance superintendent, who has been making ice in Bloomington for 23 years.

He described making outdoor ice as something of an art that requires adaptation to conditions. For example, freezing a rink meant settling for less than perfect ice. "We kinda pushed it. They weren't all in perfect condition," Hanson said.

But patience is also required. Some rinks have hydrants nearby and can be flooded by hose. But lay on too much of the warmer water coming out of water mains and it can thaw what's underneath, especially in a year like this one in which the frost that prevents drainage into the ground has been slow to thicken.

Water trucks are used to flood rinks without nearby hydrants, but they can break through more easily when the frost is thin. "You've basically lost the seal of your bathtub," said Brian Wagstrom, Minnetonka's public works director. Another factor that's worked against that city is that some rinks have paved surfaces for warm-weather use. That means the dark surface captures solar radiation and can melt ice. Wagstrom said cities like his also need to rotate staff through flooding rather than having park attendants dedicated to ice maintenance, as in some cities.

Minneapolis is flooding the zone with 50 to 60 park keepers. Some are working over the weekend with a goal of having rinks ready for Tuesday, according to Justin Long, assistant parks superintendent. That's except for Lake of the Isles, Lake Nokomis and Powderhorn Park. Because trucks are used there to haul pumping equipment for flooding with lake water, those require much thicker ice.

Minneapolis opened its first flooded rinks this week at Lyndale Farmstead, Bohanon and North Commons parks. But Loring Park got a jump on the season with a small temporary refrigerated rink that opened there Thanksgiving weekend for the Holidazzle event. That was a first experience for park officials with the technology.

But St. Paul already has four refrigerated rinks, which allowed the first to open on Dec. 3 although rains then forced its closing for a few days. It expects to open about 10 more rinks by the end of next week, with the rest open within two weeks.

But some cities already are curtailing their plans. Many try to open rinks by the holiday break for schools, which means they're already three weeks overdue. Woodbury, with one refrigerated rink, was opening three flooded rinks Saturday but won't try to open two others this winter because of the weather delay. Skating typically ends by Presidents' Day weekend across the metro area.

"I'm sympathetic for the city," said Schaefer in Minneapolis. "I'm sure they're working hard. … I'm just disappointed."

Steve Brandt • 612-673-4438