Mother Nature is not on Luke Bryan's side this week. After rain forced the country star to postpone his Lexington, Ky., 2015 Farm Tour stop scheduled for Thursday (Oct. 1), more bad weather has led to the postponement of a second show.

Bryan's Farm Tour stop in Knoxville, Tenn., scheduled for Friday night (Oct. 2) has been postponed to a date that has yet to be determined, again because of rain.

"I know you guys are mad. I am heartbroken. We schedule Farm Tour in October because it is historically the driest month of the year," Bryan writes on Twitter, adding in a follow-up tweet, "ATVs were bogging up. I will play in the rain, but I can't strand you guys in your vehicles for days.

"Been doing Farm Tours for seven years, and this is the first time we've encountered this. We will learn and constantly get better. So sorry," Bryan continues. The tweet after that reads, "Farm Tour has forever been a growing dream of mine. This year is our biggest so far. Hang in there with me. I swear I will make it count.

"Seeing country fans pile into places where no one ever thought a show would ever be possible is the most gratifying ever," Bryan concludes. "Love y'all."

The “Strip It Down” singer kicked off his 2015 Farm Tour on Wednesday (Sept. 30) in Ft. Wayne, Ind. The trek is scheduled to run through Oct. 10, with Sam Hunt, the Peach PickersChris Janson, Chancie Neal and DJ Rock joining in on the fun.

“Farm Tour is just fun to me, and it’s something that, anytime you can start something that starts small and grow it,” Bryan says. “We never want to make it this really ginormous thing that we can’t control, but we want to make sure it’s on our terms, and we love doing it. And then we want to make sure that the communities that we partner up with, from the sheriff’s office to the highway patrol guys to the colleges to the college kids, we want to make sure it’s a positive thing at the end of the day for the communities.”

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