Nearly three decades after they first got together in a New Orleans garage, the Radiators are still rocking ecstatic audiences with their soulful brand of party music.

But these days, the Rads play most of their dates outside the ravaged Crescent City. The group headlines this weekend’s Napa Valley Blues Festival — an outgrowth of the Calistoga Jazz Festival — with its first-ever wine country appearance Saturday night at Charles Krug Winery in St. Helena.

“We’re road hogs,” said Radiators guitarist Dave Malone, on the phone from his new home in Port Vincent, La. “We’re like one of those old blues bands that just kind of plays all the time.” Known for their extended sets — “In New Orleans, we’d play from 10:30 (p.m.) till 4:30 (a.m.),” Malone said —  the Radiators will have to condense their legendary jams into a mere 90 minutes at Krug: they’re scheduled to play from 7:30 to 9 p.m., following a 6 p.m. set by the high-energy Bay Area blues act Ron Thompson and the Resistors.

Band brings new CD to Valley

Malone, who lost his house in the Hurricane Katrina disaster, now lives 50 miles from New Orleans. The 2005 storm and its aftermath have left the city’s musicians “scattered all over the place,” he said.

The Radiators have just released their first post-Katrina CD, “Dreaming Out Loud,” on the jam-band label SCI Fidelity (home of latter-day tribal improvisers String Cheese Incident and Railroad Earth). Copies will be available for sale at Saturday’s concert.

The all-new tracklist of original songs — most penned by the band’s Ed Volker, a.k.a. “Zeke Fish Head” — features the slinky rhythms, bluesy vocals and electrifying musicianship that have made the Radiators a standing-room-only attraction around the country.

“We think it’s our best,” Malone said. Guest appearances include backing vocals from Susan Cowsill, of the 1970s hit group the Cowsills.

The CD has its bittersweet moments — “Heaven help the humble who turn the other cheek,” runs a lyric from the ballad “Don’t Pray for Me.” But Malone says “there’s a thread running through it of hope rather than despair.”

While Malone and his bandmates continue to recover from the hurricane damage they suffered, the Radiators are also working to raise money and awareness for other New Orleans musicians affected by the Katrina catastrophe.

The band has devoted a considerable part of the booklet in its new CD to a plea for donations to a pair of non-profits, the New Orleans Musicians’ Clinic (www.wwoz.org/clinic), which provides health services to musicians, and the Tipitina’s Foundation (www.tipitinasfoundation.org), which offers programs for music students and for working musicians affected by hurricane damage.

“This town is hurting, and it needs help big time,” said Malone. “Watching it on TV does not give the big picture.”

Calistoga gets the blues Sunday

The Napa Valley Blues Festival moves to downtown Calistoga Sunday with an afternoon of music in Pioneer Park.

Harmonica deity Norton Buffalo and his group the Knockouts are scheduled to perform at 12:30, followed by guitarist Christopher Ford at 2:30 and the Zydeco Flames at 4 p.m.

For complete information on the festival, including concert rules covering food, beverages, chairs and umbrellas, visit the Web site www.calistogajazz.com or call the Calistoga Chamber of Commerce at 942-6333