Sammy Hagar & the Circle: The weather may not scream outdoor concerts, but rock vet Hagar is always ready to scream, indoors or out. The Van Halen and Montrose alum brings his current group — featuring original Van Halen bassist Michael Anthony, Led Zeppelin drum scion Jason Bonham and hotshot guitarist Vic Johnson — to kick off the season at Mystic Lake amphitheater. The group is touring behind their week-old second album, "Space Between," a hard-rockin' collection obsessed with money, greed and corruption, best exemplified on the rollicking single "Trust Fund Baby." Opening is Vince Neil of Motley Crue infamy. (7:30 p.m. Fri. Mystic Lake amphitheater, Prior Lake, $49-$199, ticketmaster.com) JON BREAM
GRiZ: With such heavy hitters/one-hitters as Snoop Dogg, Wiz Khalifa and Matisyahu guesting on his new album, "Ride the Waves," Michigan electro-funk producer Grant Kwiecinski, 28, is moving fast toward the pop and R&B mainstream after working his way up the lineups at EDM and psychedelic/jam-band festivals for a half-decade. The album and his live show incorporates his sax-playing skills, love for classic soul music and GLBT pride, which extends to his support for the It Gets Better Project on tour. Yung Bae and Dwilly open. (9 p.m. Fri., Armory, 500 S. 6th St., Mpls., $35-$58, ticketmaster.com.)
Mountain Goats: Like the North Carolina answer to the Decemberists, John Darnielle and his elegant band — now with Superchunk/Bob Mould drummer Jon Wurster — churn out fantastical and playful but also often dark and evocative Americana/folk-rock tunes. Their latest effort for Merge Records, "In League with Dragons," is one of their weirdest. La Luz frontwoman Shana Cleveland opens. (9 p.m. Fri., First Avenue, $30.)
Jennifer Grimm: Backed by guitar ace Joe Cruz and others, this versatile Twin Cities vocalist with a big repertoire and a big personality kicks off the outdoor series at Crooners' patio, overlooking Moore Lake. (8 p.m. Fri., Crooners, $10)
Charlie Parr & Phil Cook: Duluth's acoustic folk/blues hero Parr made one of his best albums, "Stumpjumper," with Cook as producer. Four years later, they're pairing up again for what should be a memorable short tour together. Local fans know the multifaceted North Carolina-based, Wisconsin-bred Cook from his busybody work with Gayngs, his old group Megafaun and just about everybody at the Eaux Claires festivals. (9 p.m. Sat., First Avenue, $25.)
Resonance: A Sound Art Marathon: Inspired by the legendary 1980 New Music America festival, this 10-hour free event features a remarkable array of music experimenters. Philip Blackburn, dean of the local new-music scene, kicks things off at noon. Golden Valley-bred jazz piano star Craig Taborn will partner with sound artist Camille Norment in a performance involving vintage car parts and Benjamin Franklin's famed glass armonica. Instrument maker Walter Kitundu — whose works include a turntable-driven "Phonoharp" — will collaborate with vocalist Mankwe Ndosi. It all culminates with an LED light installation by London-based artist Haroon Mirza, while Lebanese composer Tarek Atoui creates a live score using sampled sounds. (Noon-10 p.m. Sat., McGuire Theater, Walker Art Center.)
[UPDATE: The Palmieri show has been cancelled.] Eddie Palmieri: Hoping to create awareness for the ongoing post-hurricane struggles of his homeland of Puerto Rico, the nine-time Grammy-winning pianist will explore the expansive, percussive sounds that have made him a Latin jazz icon. At age 82, the Nuyorican is not slowing down. Last year, he released two albums, "Full Circle," on which he reimagined eight compositions from his salsa era, and "Mi Luz Mayor," which chronicled his love story with his late wife, with a little help from guitarist Carlos Santana and vocalist Gilberto Santa Rosa. (7 p.m. Sun. Ordway, $50-$150, Ordway.org)
L7: Sounding as strong as ever at First Avenue last year on their first tour of this millennium, one of the grunge era's most beloved and influential bands has now returned with a powerful record: "Scatter the Rats," on Joan Jett's Blackheart label. They're coming back around with the not-to-be-missed Mexican punk band Le Butcherettes opening. (8 p.m. Sun., Varsity Theater, $30.)