DETROIT -- Dan Craig walked out of Ford Field on Tuesday night and knew trouble was brewing.
The NHL's facilities operations manager, in charge of the ice surface for this weekend's Frozen Four being played in this cavernous NFL stadium, could feel a change in the weather -- and one that wasn't for the better.
The normal temperature here in early April is 53 degrees. Thanks to an unwelcome warm front that arrived in town overnight, the thermometer reached 67 on Wednesday, with a relative humidity of 80.
"Humidity is not a friend of ours," Craig said. "What it does is it falls to the ice surface because it's the coldest spot in the building and it automatically attracts it like a magnet. When we get too much humidity, it starts to get a little sticky and gummy and really affects the feel of the puck from one pass to the next."
When this year's Frozen Four was awarded to Ford Field (via the Central Collegiate Hockey Association and Detroit Sports) back in June 2005, there was no way of predicting the weather.
But there is no way it should matter, either.
Enter Craig.
As the NHL's ice guru, he has overseen the first three NHL Winter Classics as well as many other nontraditional ice events. And he's always involved through the Stanley Cup finals when games have been played in June in sweatshops such as Raleigh, N.C., and Tampa, Fla.
Craig knows this weekend could be a challenge if the weather stays warm.
The temporary rink was installed in a two-day period last week. It takes 10,000 gallons of water to make one inch of ice, and the plan is to have 2.5 inches when the puck drops Thursday for the first national semifinal between Rochester Institute of Technology and Wisconsin (5 p.m. ET, ESPN2 HD). The ice was at 2 3/8 inches on Wednesday.
Craig said the desired temperature of the ice surface is 22 degrees, and ideally the building would be at 60 degrees for the ice-making equipment to operate at maximum efficiency.
The one factor that hasn't been introduced into the mix yet is the crowd. The expected number of fans is somewhere north of 30,000. That would break the indoor hockey record of 28,183 set back in April 23, 1996, for an NHL playoff game between the Philadelphia Flyers and the Tampa Bay Lightning at Tropicana Field.
"The ambient air is a huge factor," Craig said. "We had the building down to 55 degrees the other day, so we know it can be cold. We're going to try and get to 57 degrees when we open the doors tomorrow.
"We know there's a cold front moving in, and I just do my prayers at night and hope it gets here."
The Frozen Four teams practiced here for the first time Wednesday afternoon. And the reaction about the ice from most was cautiously optimistic.
"I don't think the ice is anything worse than what we've skated on before," RIT forward and Detroit native Cameron Burt said. "It's just something we're going to have to deal with, and it's something that every team is going to have to deal with, so we can't make any excuses about the ice."
Wisconsin has some recent experience with unique venues, having hosted Michigan in front of 55,000 fans at the Camp Randall Classic in February. And Boston College, which will play Miami (Ohio) in the second semifinal on Thursday night (8:30 p.m. ET, ESPN2 HD), played in the Frozen Fenway game in January.
Both teams talked about the need to make an adjustment to the sight lines and the crowd position in those stadiums. And that will be necessary at Ford Field, too. But both of those outdoor games were played when the weather didn't negatively affect the ice.
"It was pretty much the same out there, other than the temperature," Wisconsin forward Blake Geoffrion said as he tested the Ford Field ice. "It was pretty humid out there. Usually, my hair is not going to be wet all the way through until about the third period, and it was pretty much wet after the first 15 minutes. I think the temperature is going to be a huge factor. They're still working on the ice, but it wasn't too bad."
The other major adjustment for the players will be the walk to and from the ice.
Miami, the No. 1 overall seed, has the dressing room closest to the rink. It took 154 steps to go from the room to the ice. Add another 100 steps for RIT, which is the lowest seed here.
The walk is so long that the goaltenders, because of their heavy equipment, will be shuttled back and forth on golf carts.
Despite all the focus on the quality of the ice on the eve of the Frozen Four, the wow factor of playing in an NFL stadium wasn't lost on the players.
"We've played on some tough ice surfaces the last couple of months, and today was not the best ice, but it's pretty amazing what they've done so far -- especially on a football field," RIT captain Dan Ringwald said. "Once you get around, it's just another ice hockey surface, and, once the game starts, you have to focus on playing."
Craig hopes the spotlight for the rest of the weekend will be on the hockey that is played and not on the ice surface it is played upon.
David Albright covers college sports for ESPN.com and can be reached at espncaa@gmail.com.