By 8:00 a.m. on Friday, the S.S. Jam Cruise was docked in the Central American port of Roatán, Honduras. As the festival’s first excursion day, attendees had several options: Some enjoyed a jungle zipline, while others relaxed by the water. As per tradition, a group of musicians and fans also teamed up for the festival’s annual Positive Legacy day of service, planting a community garden, building a playground and painting a mural designed by Honduran graffiti artist REI Blinky.

The call for “All Aboard” was at 2:30, and by 3:00 Jam Cruise was back on the seven seas. Music didn’t officially start for another hour, but keyboardist Kenneth Crouth (who is performing with Karl Denson this weekend) couldn’t help but take a seat at the Atrium’s grand piano and treat fans to an impromptu performance. As Crouth’s music drifted upstairs to O’Sheehan’s pub, it provided some ambiance to Ivan Neville’s annual Texas Hold ‘Em tournament.

The Main Squeeze made their Jam Cruise debut as the first scheduled performers of the day, opening with their new song “Sweat.” Following fan favorite “Message to the Lonely” the skies began to look stormy, but that didn’t deter the audience who were enjoying some of the weekend’s many free beers. “It’s an unbelievable experience sitting on this boat with all these incredible musicians and friends and family, people who have been watching us since we were a little band in Bloomington, Indiana” Frontman Corey Frye said to the crowd before the band jumped into a cover of Childish Gambino’s R&B hit “Redbone.” That being said, the real MVP of The Main Squeeze’s set was Mother Nature, who chose to open the skies up and pour down rain right as he band laid into “War Pigs” by Black Sabbath.

As rain poured down outside, Jam Cruisers found shelter at the Atrium with Leftover Salmon co-founder Vince Herman. Herman started off his bluegrass jam solo, with a ditty he wrote about Jam Cruise just a couple of nights prior, but he eventually welcomed members of Horseshoes and Hand Grenades, Lil’ Smokies and The Spot to join him, playing standard bluegrass tunes as well as a cover of “You Don’t Know How It Feels” by Tom Petty. Eyeing Andy Frasco of Andy Frasco and the UN in the crowd, Herman implored him to take a seat at the piano. “I’ve never played bluegrass in my motherfuckin’ life,” Frasco laughed, before improvising a song. Herman even invited a Jam Cruise staffer named Sean to play the upright bass and sing lead on the bluegrass classic “Rocky Top.” Herman threw the young players for yet another loop when he decided to sing the lyrics to The Eagles’ “Hotel California” instead.

Afterwards, Holly Bowling played her second set of the weekend. And while rousing versions of the Grateful Dead’s “The Other One” and Phish’s “Squirming Coil” were divine, fans were eying the acoustic guitar next to Bowling’s piano, waiting for Tom Hamilton to inevitably join his Ghost Light bandmate for a jam. The wait was well worth it when Hamilton and Bowling dove into a lengthy “Terrapin Station,” complete with a segue in and out of Radiohead’s “There There.”

Less than an hour later Tom Hamilton was back in front of a crowd, joining George Porter Jr., Steve Kimock, Jeff Chimenti, Dan Lebowitz and John Morgan Kimock for a set of Voodoo Dead at the Stardust Theater. As opposed to the outdoor pool deck stage, the indoor Stardust gave the band a contained atmosphere to bounce their sound around. You could hear George Porter Jr. clearer in the mix, and the sloped theater gave fans better eye lines. The band kicked off their 90-minute set with a “Shakedown Street” opener, and eventually made their way to a “Scarlet>Fire” jam that contained a spontaneous “Purple Haze” tease by GPJ. The all-star Dead tribute closed with a “Goin’ Down The Road Feelin’ Bad,” featuring an extra Jam Cruise themed verse, with Lebowitz singing, “Just wish this party would never end.”

Meanwhile Lotus was up on the pool deck from 8:00-10:00 p.m. The jamtronica quintet pleased fans with originals like “Spaghetti” and “Bubonic Tonic,” but their set hit a slight hiccup when the stage’s PA system cut out right at the peak of “It’s All Clear To Me Now.” The band quickly transitioned into a percussion jam, with all five members joining in, and thankfully, once the sound was fixed they were able to jump right back into the jam.

As the weather got misty, Galactic welcomed artist-at-large Mike Dillon to join them on percussion and got rowdy with songs like “Hey Na Na.” Upstairs, Psychedelic funk band Pigeons Playing Ping Pong made their Jam Cruise debut at the intimate Spinnaker Lounge. In typical P4 fashion, it didn’t take long for the venue to fill up and become a sweaty dance party. Warming up for their pool deck set on Saturday, the band grooved along with their fans to songs like “Melting Lights” and “Something For Ya,” and even busted out a version of Prince’s “1999” with background horns by fellow Baltimoreans Mario D’Ambrosio and Chris Sgammato.

Shira Elias’ Jazz Lounge set from Midnight-2:00 a.m. was filled with special guests from Karl Denson and his KDTU guitarist DJ Williams, to Corey Frye and Ben “Smiley” Silverstein from The Main Squeeze. And as of press time, Roosevelt Collier’s superjam was equally star-studded with appearances by Robert Randolph and Nigel Hall. Hall was clearly in the mood to jam, as he also made a stop by Marcus King’s 1:30 a.m. set on the pool deck.

Jam Cruise continues tonight in Grand Cayman Island, with performances by Keller Williams and Karl Denson’s Tiny Universe as well as second helpings of Dumpstaphunk, Pigeons Playing Ping Pong and Aqueous.