INDIO, Calif. -

The desert is welcoming its population-doubling influx of music fans for the start of the Coachella Valley Music and Arts Festival tomorrow.

About 80,000 people are expected at the Empire Polo Club for each day of the two-weekend festival, which starts Friday and runs through Sunday, then reprises itself April 19- 21. Both weekends are sold out.

During the 2012 festival, the first time it was expanded to two weekends with identical lineups, about 158,000 visitors to the Coachella Valley and Indio helped add more than $47 million to the local economy, according to Billboard.

"We were happy with the outcome of the music festival last year and had a meeting (Wednesday) morning and said, OK, let's make this one better," said Jim Curtis, Indio's community services manager.

The Yeah Yeah  Yeahs, Blur and the Stone Roses are Friday's headliners. Phoenix will be among the top acts Saturday, and the Red Hot Chili Peppers, who have played the festival twice before, will be the main draw Sunday.

The Stone Roses from Manchester, England, open the festival about 11:40 a.m. Friday on the Coachella Stage -- one of six.

Here's a rundown on road closings in Indio:

      -- Avenue 49 between Hjorth and Monroe streets

      -- Avenue 50 between Madison and Jackson streets

      -- Hjorth between avenues 49 and 50 and Madison between avenues 49 and 52 will be closed Friday through Sunday and April 19-21.

Delays are expected on Washington, Jefferson, and Monroe streets and Highway 111 on those days.

Indio's  non-emergency concert hotline is (760) 541-7800.

Afternoon highs are forecast to be in the upper 80s through Sunday, with winds generally less than 10 mph, according to the National Weather Service.

Indio police spokesman Ben Guitron urged people unused to hot weather to dress lightly an drink plenty of water.

Indio will receive law enforcement and traffic control resources from the Riverside County sheriff's deputies.  The city's officers along with others from nearby police departments will work with private security guards paid by Goldenvoice.

"We obviously look for people to obey the rules," Guitron said. "It's a city within a city," he said."

People caught with illegal drugs or who have had too much to drink will be dealt with just as they would be any other day in Indio, he said.

"They need to come and enjoy themselves, rather than spend time with the Indio Police Department and time in the county jail," Guitron said.

Paramedics will be standing by to handle any medical emergencies.

"It's a constant adjustment, a never-ending plan," Guitron said, referring to the logistics of managing big crowds.

Recently widened Monroe Street seemed to help keep traffic flowing last year, he said.

"We're really excited because of street improvements, so as far as traffic we had minimal issues last year. They've done more this year, so we're excited to see how that's going to work out," Guitron said.

The two music festivals -- Stagecoach is held over the final weekend in April -- have a "huge" economic impact on the Coachella Valley.

"It's a big number for the entire valley, these three weekends. It's the music capital of the world right now," he said.

According to an economic impact analysis done last October by Development Management Group in Palm Desert, Coachella's and Stagecoach's economic impact in the Coachella Valley last year was $254.4 million -- $89.21 million to Indio.