Summer only gets busier, from local clubs and stadiums to festivals in Marshfield and New Bedford to the outer reaches of Cape Cod. Canadian alt-country rockers The Sadies have been welcome visitors through the years, including backing turns for singers from Neko Case to the Tragically Hip’s Gord Downie — and they’ll be welcome on their own at Somerville’s Once Ballroom on Friday. The same night brings the droll songsmith Randy Newman (“Political Science” seems extra-topical these days with our North Korea standoff) to Lowell Summer Music at Boarding House Park, the mainstream country valentine of Tim McGraw and Faith Hill to TD Garden, the country-punk Waco Brothers (including the Mekons’ Jon Langford) to Atwood’s Tavern and indie-rockers Deer Tick to Prescott Park in Portsmouth, N.H. And down on the Cape, local roots-reggae favorites John Brown’s Body hit the Beachcomber in Wellfleet both Friday and Saturday nights.

Saturday includes big shows in town with New Kids on the Block and Boyz II Men at Fenway Park, plus Broadway and film actress/singer Idina Menzel at Blue Hills Bank Pavilion. But on the South Shore, there’s also the three-stage Levitate Music Festival at the Marshfield Fairgrounds, including Dispatch (pictured), Umphrey’s McGee, Deer Tick and Rubblebucket on Saturday and Ziggy Marley, Lake Street Dive and Twiddle on Sunday. It’s “officially” sold out, even if extras float about in the usual channels. Here’s the whole Levitate schedule. And then there’s the New Bedford Folk Festival the same two days, leaning to song swaps and workshops that bring together such singer/songwriters as Catie Curtis, Aoife O’Donovan, Patty Larkin, Vance Gilbert, Pete and Maura Kennedy, and The Nields. Here’s that New Bedford schedule.

The Sinclair’s also busy in Cambridge this weekend, highlighted by jazzy retro-roots kingpin Pokey LaFarge on Saturday and the joyously ramshackle roots-rocker Langhorne Slim & the Law on Sunday. And Berklee-bred rocker Melissa Etheridge shifts from sharing holiday fireworks with the Boston Pops on the Esplanade to a full date at Lowell’s Boarding House Park on Sunday as well.

Tip ahead: The Moody Blues — still featuring guitarist Justin Hayward and bassist John Lodge on vocals, and Graeme Edge as one of two drummers — highlight their 1967 landmark Days of Future Past, a prog-rock harbinger with its dreamy fusion of rock and classical music, at Blue Hills Bank Pavilion on Monday.