It didn't seem much like a 'Long Hot Summer' last evening in Nashville. With temperatures in the 40's and dropping, Keith Urban and Richard Marx were celebrated with a party marking their No. 1 summer song from last year. Despite the invitation from Keith for people to come out in "flip flops, a Hawaiian shirt and shorts," only one person at the entire fete took the superstar's attire request seriously.

Keith told The Boot that the song was written after the devastating floods of 2010 in Nashville. All of his guitars were lost, and he had to borrow one from someone at Studio Instrument Rentals, where he and Richard were holding their writing session. Although they had gotten together to finish another song, that one was pushed aside to another day when the idea for 'Long Hot Summer' came along.

"I like to have at least one of these kinds of songs on my album," Keith explained. He and Richard worked on the song but didn't get it finished. Shortly thereafter, Keith was opening for the Eagles in Chicago, where Richard lives. He called and invited the pop legend out for a songwriting session.

"We were sitting on the bus working, trying to finish the song, when Joe Walsh (Eagles guitarist) came onto the bus," Keith relayed.

"Joe had played on my first album and we hadn't seen each other in a long time," Richard added. "He came on, and we were talking and he finally stopped and said, 'Am I interrupting something?'

"We had to tell him we were trying to finish a song and he was like, 'Oh, I can come back.' So he left, and we finished it and did a work tape on it. Then Keith put it on his album! It's one of my favorite songs that we've written. You always hope that when someone else records something you wrote, they will do it justice. When Keith sent me the recording of it after he had been in the studio, I called my family in to listen to it. There was just this one moment of 'I hope it doesn't stink' before I hit the button, and it was great."

The song is very special to Keith, as well, who counts Richard as a friend and invaluable co-writer. The singer relays that when the two first met through a publisher in Nashville, they hit it off so well that they would do anything but write because they just enjoyed each other's company. So when Keith called Richard and suggested that they get together to finish this other song they had started, they never did. They came up with 'Long Hot Summer' instead, and the other song remains unfinished. So we're hoping for another Keith Urban/Richard Mark No. 1 party invitation later this year!

Watch the 'Long Hot Summer' Video

if(typeof AOLVP_cfg==='undefined')AOLVP_cfg=[];AOLVP_cfg.push({id:'AOLVP_1107223333001','codever':0.1,'autoload':false,'autoplay':false,'displaymnads':true,'playerid':'89761511001','videoid':'1107223333001','width':476,'height':357,'playertype':'inline','stillurl':'dynamic','videolink':'#','videotitle':'dynamic','videodesc':''});

More From TheBoot