As the Norwegian Pearl sailed on past the coast of Cuba on its way to Jamaica, Jam Cruse 15 saw its first full day of music aboard the ship, with an eclectic offering of genres, sit ins and collaborations for day two.

The music got started with San Francisco bluegrass outfit The Brothers Comatose, who took to the Pool Deck stage in the early afternoon sun for an upbeat set that featured a cover of the Grateful Dead’s “Brokedown Palace” and closed out with an energetic guest spot from lap steel master Roosevelt Collier.

Next up on the deck was a set from classic jamband mainstays Percy Hill, whose jazzy set was punctuated by a mini-Women’s March around the Pool Deck, a show of solidarity with the events happening in Washington DC and in several cities around the United States on Saturday.

Inside, a New Orleans bass battle for the ages was taking place between George Porter Jr. and Tony Hall of Dumpstaphunk, introduced as “a legend and his protege,” while Nathan Moore played a small set in the main atrium that featured keyboardist Marco Benevento and a nod to the duo’s days in their band Surprise Me Mr. Davis.

Back on the Pool Deck, Ivan Neville and Cris Jacobs’ Neville Jacobs project delivered a genre-spanning set of funk, blues and more that featured help from Turkuaz’s Shira Elias, plus sit ins from Cyril Neville on the Grateful Dead’s “Fire On the Mountain” and the Shady Horns’ Ryan Zoidis and Benny Bloom for Peter Gabriel’s “Sledgehammer,” plus a cover of Buffalo Springfield’s “For What It’s Worth.” Inside the ship, Love Canon was offering up their brand of ‘80s classics with a bluegrass flavor.

As the sun dipped behind the Cuban coastline, Kamasi Washington and his band delivered their second set of the cruise on the Pool Deck, once again welcoming out Rickey Washington and improvising on originals and other tunes like the jazz standard “Cherokee,” led by vocalist Patrice Quinn. Immediately after, Motet keyboardist Joey Porter then played an intimate set in Bar City that featured several guests including bandmate and vocalist Lyle Divinsky and Turkuaz’s Sammi Garett and Shira Elias.

At the same time, word came down over the ship’s speaker system that, due to weather, the cruise would not be making its scheduled stop on Monday at Grand Cayman Island. Instead, Jam Cruise 15 will get an additional day at sea, which will feature a Grateful at Sea collaboration with Steve Kimock, Reed Mathis, Dan “Lebo” Lebowitz, Jay Lane and more special guests, plus impromptu jams around the ship.

After a short break in music, Twiddle kicked off the night’s festivities with a reggae-rocking performance on the Pool Deck that featured some of their live favorites and an extended jam with moe.’s Al Schnier, who faced off with Twiddle frontman Mihali Savoulidis in a high-energy guitar solo exchange.

At the same time in the Stardust Theater, Widespread Panic keyboardist JoJo Hermann was leading his Slim Wednesday project through some blues and New Orleans boogie. The performance would also feature a short guest spot from the legendary Col. Bruce Hampton, who joined in on vocals for “Stagger Lee” after Hermann nodded to Hampton’s oft-rumored mysticism by telling the crowd “I’ve been trying to get roulette numbers off him all week.”

Houston group The Suffers then took over the Spinnaker Lounge, with frontwoman Kam Franklin, who earlier led the Pool Deck in a collective wedding ceremony, leading the way through a ripping performance that included covers of Outkast’s “Spottieottiedopaliscious” and The Specials’ “Ghost Town,” while Kamasi Washington collected members of his band and others for a Crystal Atrium jazz lounge jam session that featured a cover of Herbie Hancock’s “Maiden Voyage.”

After many of Karl Denson’s Tiny Universe participated in the previous night’s Jam Room action, the full band had their first of two proper sets on the Pool Deck, while the Benevento/Russo Duo marked their official reunion in the Stardust Theater. The longtime collaborators and Almost Dead bandmates offered up one of the highlights of the festival-at-sea so far, with Russo’s impressive power-finesse drumming and Benevento’s jovial multi-keyboard playing, while saxophonist Skerik joined in at one point with horn flourishes and metal-frontman stage antics.

The Hip Abduction then brought their energetic live show to the Spinnaker Lounge, and Lebo led a performance of his magicgravy project, which pairs him with The Motet’s rhythm section of bassist Garrett Sayers and drummer Dave Watts.

While Dopapod was closing out the Pool Deck into the morning hours, Lettuce packed the Stardust Theater with its biggest crowd of the cruise yet, delivering a typically expansive performance of their arena-funk live favorites.

The night’s Jam Room session was hosted by Steve Kimock, who was joined by Reed Mathis, Robert Walter and moe. drummer Vinnie Amico and more. Everyone Orchestra leader Matt Butler came on stage to conduct a jam of the collected musicians, plus Roosevelt Collier, who was called in from the audience. A line change then took place, with JoJo Hermann and Todd Stoops taking their places behind the keyboards, Amico’s bandmate Al Schnier bringing on his guitar, George Porter Jr. gracing the stage with his bass and Kam Franklin adding some improvised vocals. As the different musicians moved on and off stage, Porter Jr. and Kimock led the jamming before the bassist took lead vocals on a cover of the Dead’s “Sugaree.”

Jam Cruise will continue today after a stop in Ocho Rios, Jamaica, with music from The Meters, Galactic, Twiddle, GRiZ, The Motet, Turkuaz and more.