As the heat advisory began Friday afternoon in the Twin Cities, so did the Irish Fair of Minnesota.

"We practice all year for this. We rehearse. And we are just so excited to be here, and we love being on stage," said Molly O'Malley.

This is the 45th year of Minnesota Irish Fair. Organizers expect somewhere between 15,000 and 25,000 people to attend the event, which will take place on Harriet Island in St. Paul.

O'Malley and her fellow Rince Na Chroi dancers have been at the fair long enough to know they need to be prepared for anything, even a heat advisory.

"We're ready for the heat. We've got these nice, sleeveless dresses so that's awesome," said O'Malley.

For others, there are refillable water stations and plenty of shade covering vendors and concert stages.

"The heat is a thing, you know we're Minnesotans, we get used to it. We have plenty of ways for people to stay cool and come out and have a really great time this weekend," said Macy Ashby, co-chair of the Irish Fair.

There will be 10 food vendors and dozens of other marketplace vendors who say despite a Friday heat index of 100 degrees or more, they're ready to sell.

Stuart Marley drove cross country to sell his merchandise, which includes a line of Guinness clothing. He's been coming to the Irish Fair for years and knows the weather is even more unpredictable than the sales.

"We sell fragrances. We well Hannah Hats that are actually made in Ireland," said Marley. "I think two years ago we had hail on a Friday. Massive, massive, hail."

Hopefully that won't be the case this year, but even if it is, bagpiper Ally Crowley-Duncan plans to play right through it.

"It's a tough instrument. You kind of sweat in all climates when you play it but hydration, electrolytes. That's my goal. We've done it before and we'll do it again," said Crowley-Duncan, who is also known as "Ally the Piper."

The Irish Fair begins at 3 p.m. Friday and will run through 7 p.m. on Sunday.