Autumn came late this year to San Diego, "America's Finest City." But the damp, chilly sea air belied the rising temperature inside the Gaslamp District's House of Blues, where Grace Potter and the Nocturnals (GPN) heated things up with their scorching stew of roots-inspired rock that included liberal dashes of blues, ballads, gospel, funk and good ol' fashioned hard-driving rock-n-roll. Except for a sprinkling of shows near GPN's Vermont home where they headlined, GPN is ending a whirlwind U.S. tour as the warm-up band for headliner Brett Dennan, a bare-footed, vest-wearing folk-troubadour whose mellow vibe seems a wide departure from GPN's harder-driving tempos. Even though GPN had a few nights off since their previous gig, there was little rust evident, and the brief hiatus did little to dampen the band's enthusiastic bid to win over an estimated crowd of five hundred seemingly ardent Dennen fans. Unfortunately for those GPN die-hards who came to see them specifically, the band was cramped into an opening slot that lasted barely an hour, and the setlist varied little from previous gigs on this tour. Still this was Grace Potter and the Nocturnals, and a little GPN is better than no GPN at all.

The band's refreshing "girl power" brand of rock-n-roll is a potent symbol of the fusion of otherwise opposing female forces: sheer, raw, sexually-charged power on the one hand, and a delicate ' dare we say ' grace on the other. Decked-out in a spangly sequined dress and platform heels, Potter stormed the stage to a microphone stand laced with red roses, and kicked the night off with "Medicine," a cut off the band's new album that also has the distinction of being the first song written by all the members of GPN version 2.0, which now includes newcomers Catherine Popper on bass, and Benny Yurco on rhythm guitar. This shaggy-haired, five piece band then lit into a ripping "Ah Mary," which contains lyrics that could aptly capture this feminine dialectic: "She'll make you cookies then she'll burn your town." Another new tune full of possibility, "Oasis," was followed by probably GPN's most recognizable tune, the power ballad, "Apologies." Although a studio version appeared on "One Tree Hill," here it benefitted from Potter's keyboard talents and crystal clear voice, which sounds as amazing live as it does in the studio. While this song gives credence to all the Bonnie Raitt comparisons, the other tunes, including "Only Love," conjure up images of 26-year-old Potter's other, old soul, rock goddess doppelganger -- Janice Joplin -- and allowed Potter to show off her awe-inspiring, octave-jumping vocal pipes.

Potter offered up the opportunity to use this San Diego audience as "guinea pigs" for a few other new album tunes, such as "Tiny Light," featuring the entire band in some lilting vocal harmonies, and "Colors," which was evidently inspired by Barack Obama's election. Potter confessed that, with the tour winding down, this GPN 2.0 version, including original GPNers Matt Burr on drums and Scott Tournet on lead guitar, was really coalescing into a family. This new familial synchronicity was felt in the straight-ahead rocker, "If I Was From Paris," with Potter strapping-on a Flying-V guitar and sharing some interplay with the band's two other axe-men. The gospel-tinged "Nothing But The Water I" was a pure acapella tour de force with Potter's solo vocal soaring into the rafters. From behind the keys, Potter ended the abbreviated set with blazing versions of "Nothing But the Water II" and "Sweet Hands," which featured the one big opportunity for the whole band to truly jam things out. Popper's bass held down the low register while the guitars attacked in a sonic assault. This jam interlude also included a nifty group drum solo in which all five members banged away on the individual segments of Burr's drum kit. The result, while it sounded like the obligatory parking lot drum circle at, say, a Phish show, was oddly melodic and built to a breakneck, satisfying crescendo.

Potter, who can't seem to stay still, is a monumental force-of-nature in concert. She vamps like a Mae West sexpot, struts across the stage like a spirit possessed, and occasionally lords above her keyboards like Jerry Lee Lewis when the music enraptures her. That's all part of her energetic allure ' as well as her sheer musical talents and striking looks, that is. And her band is a solid and formidable match for her too. For a crowd that originally may have been anxiously awaiting Bret Dennen's appearance, it was apparent that GPN's innumerable musical and live concert attributes won them over by the time band introductions came around a mere eleven songs after the band first hit the stage. Potter's admonition to the crowd, "Are you feeling it, San Diego?!," was met with a heartfelt verve that had all the zeal of new converts (as also evidenced by the hearty CD sales afterward). It's clear that GPN is catalyzed by its new band chemistry. Unfortunately, this truncated set was merely a taste of what a full-fledged GPN show could and should be. Here's hoping that the band can really spread their wings on Sunday, when the band headlines their own show at the legendary Fillmore Auditorium in San Francisco.