98 Degrees Make Surprise Appearance With New Kids At MixTape Festival

Kelly Clarkson, DJ Pauly D also hit the stage at the inaugural Pennsylvania fest.

HERSHEY, Pennsylvania- After putting on their ponchos, fans braved the rain and made their way out to Hershey Stadium for day one of the first-ever Summer MixTape Festival.

And you can't blame them for putting up with the downpours, since the lineup was any pop lover's dream.

"Jersey Shore" star DJ Pauly D was one of the first to take the stage and certainly got the party started. When MTV News caught up with him before his performance, he said he was ready to bring the club to the crowd.

"I'm going to bring a lot of energy, I'm going to get everyone in there fist pumping, you know how i do it," Pauly D said. "A lot of dance music, a lot of music that is upbeat, get the energy up there. I got to get their fist pumping, I got to do what I do."

Next up were fan favorites New Kids on the Block, who were making their first North American appearance of the year. "It's big for us; it's big for the fans. We're excited to be here, to see the fans again," Jordan Knight told MTV News.

Kicking off their first of two nights of performances — NKOTBSB will perform on Saturday — the group put on a memorable show, playing all of their hit songs including "Step by Step," "The Right Stuff" and "Summertime."

But the biggest surprise of their show came during the encore when 98 Degrees reunited on for the first time in 10 years to"Hangin' Tough."

Check out photos from the 2012 Summer Mixtape Festival!

On top of that, NKOTB's Joey McIntyre switched stages and joined the night's closing performer, Kelly Clarkson, who told the crowd she was "very nervous to follow New Kids on the Block," in a duet for "Don't You Wanna Stay."

Clarkson then continued to rock the crowd with hit songs including, "Behind These Hazel Eyes," "Stronger" and a festival-goer requested cover of Carly Rae Jepsen's "Call Me Maybe."

We will see if Jepsen returns the favor on Saturday when she performs, along with the Wanted, LL Cool J and NKOTBSB, at day two of the MixTape Festival.