BRIDGEPORT — This summer marked the 20th anniversary of Gathering of the Vibes music festival, and it fell on the weekend of what would have been Grateful Dead founder Jerry Garcia's 73rd birthday.

But in many ways, the 2015 gathering at Bridgeport's Seaside Park, July 30 through August 2, was more a coming together of various tribes of fans each making a pilgrimage to see one of more of their favorite bands, and landing in a mixing pot of artists that included Wilco, Weezer and a couple of supergroups bumping up against sets from New Riders of the Purple Sage, The String Cheese Incident, Doyle Bramhall II, the perky, driving funk of Connecticut's own Kung-Fu, and festival openers Primitive Souls.

There was only one place in the line-up for fans to go to experience authentic Grateful Dead material, since Grateful Dead co-founder Bill Kreutzmann was the only member of that seminal psychedelic era band to appear on the schedule.

And Kreutzmann didn't disappoint. He led his current band, Billy & the Kids, through a Dead heavy set that included "Mexicali Blues," "Greatest Story Ever Told," "Dancing In The Streets," and the moving Jerry Garcia ballad "Black Muddy River."

The weekend concert was also a reunion of sorts for members of the Allman Brothers with appearances by Warren Haynes, Jaimoe, Derek Trucks, and Gregg Allman himself. Besides welcoming Trucks for a blistering "Southbound" encore, Allman showcased a fuller, bluesier ensemble trading long guitar solos for a horn section that gave familiar hits like "I'm No Angel," "Midnight Rider" and "Whipping Post" new flavor.

Warren Haynes triple-dipped at this year's Vibes, sitting in during Kreutzmann's Saturday afternoon set, playing a full set with his rootsy pals from Railroad Earth, and then leading a late night jam with the Seaside Allstars super group featuring George Porter Jr, Branford Marsalis, Jackie Greene, Joe Russo, and Marco Benevento.

The All Stars — with only a few hours of practice — came off like they've been touring together for years, turning in a smoky "Low Spark of High Heeled Boys," a fiery take on the Allman Brothers "Dreams," and heading off into the night at 2:45 am to a funky cover of "Thank You for Letting Me Be Myself."

Tedeschi Trucks Band turned in a top-notch, amped up set of rock and blues following the electrifying Sharon Jones and Dap Kings — the highlight of Friday afternoon. Jones was nothing short of inspiring, soldiering through an electrifying set of R&B after revealing to the audience that she was inspired to give her all and playing every show as though it might be her last following a recent diagnosis of pancreatic cancer.

Opening day Thursday had a few white knuckle moments that sent ground staffers scrambling to protect fans and artists alike when hours of threatening clouds finally opened up with monsoon downpours, wind gusts and lightning just as perennial Vibes player Ryan Montbleau handed off to Strangefolk.

Laughing and cursing the sudden spate of bad weather, Strangefolk worked some musical voodoo, launching into the Dead's "Here Comes Sunshine" and literally driving the rain away over the course of a six or seven minute jam.

After about 20 minutes of rainy mayhem, only large puddles and mud remained, much to the delight of families toting children who frolicked beside the many children at heart adults kicking up a few globby splashes as they made their way across the concert field.

Friday dawned with the promise of sun and temps in the low 90s, bringing early risers out for back to back sets from Twiddle and the second supergroup to grace this year's festival, The Word, featuring John Medeski (Medeski Martin & Wood), Robert Randolph (Robert Randolph & the Family Band), brothers Luther and Cody Dickinson (North Mississippi Allstars), and Chris Chew.

As day two drew to a close, fans got another eclectic taste of Jerry Garcia, as interpreted through David Grisman and Peter Rowan, his former bandmates and surviving members of Old & In The Way. Complimented beautifully and with great sensitivity by The String Cheese Incident, the hour-long evening set washed across the thousands of Vibes fans as a light breeze fanned in from across Long Island Sound.

Just about 24 hours later, on Saturday evening, Wilco provided a study in musical contrasts crashing haunting vocals and sparse guitar passages with eruptions of counterpoint rhythms and screeching feedback. They performed their entire new album, Star Wars, before churning out crowd-pleasing tunes including "Handshake Drugs," "Via Chicago" and "Random Name Generator."

Following the annual Peace Flag Ceremony n Sunday, hosted by Woodstock alum Wavy Gravy, the Preservation Hall Jazz Band hit the stage combining raw N'Orleans-flavored classics with a rousing Motown medley that combined The Jackson 5's "I Want You Back" and Stevie Wonder's "Sir Duke."

Dweezil Zappa saw "gremlins eating all his time," as technical problems plagued his band from the start. Despite frequent complaints from the stage, Zappa Plays Zappa did Frank Zappa proud with spot on renditions of "Baby Snakes," "Dancin' Fool," "Cosmic Debris," and a fantastic new song, "Pajama People," that could have easily been penned by Dweezil's dad 30 or 40 years previous.

The festival wrapped up with a well attended double hit featuring Weezer, mixing new material like "Back to the Shack," with crowd pleasers and sing-alongs "Beverly Hills," "Sweater" and "Buddy Holly." Show closer Ben Harper with his band the Innocent Criminals sent the crowd home from another ultimately successful Gathering of the Vibes with "Brown Eyed Blues," "Roses From My Friends," and "Better Way."

All in all, this 20th anniversary celebration that began as one-off tribute show following the death of Jerry Garcia, has grown into one of the most diverse showcases for new and legacy acts that incorporate a broad variety of styles with a common core of fun loving jam band sensibility.

Kudos to Vibes founder Ken Hays and his small army of capable staffers for keeping things safe, interesting, and perhaps more entertaining for more attendees than ever before.