It almost didn’t happen. Strapped-for-cash sponsors had pulled out of the annual Twin Cities Jazz Festival, formerly known as the Hot Summer Jazz Festival, and organizers were ready to cancel this year in hopes of returning in 2010.

In mid-March, we learned that the show will go on -- in St. Paul only, not in Minneapolis; for three days, not ten. Now we know the lineup. Given the economy and the timing, it’s impressive, with two national acts holding down the main stage in Mears Park in Lowertown and other nationally (and internationally) known artists performing at other venues linked to the festival.

The headliners are Rock and Roll Hall of Famer Allen Toussaint and Esperanza Spalding. Toussaint is the New Orleans singer, songwriter, pianist, producer and arranger whose most recent CD, “The Bright Mississippi,” is a celebration of jazz standards. Spalding is the 24-year-old bassist, singer and composer who performed at the Dakota in March to SRO crowds and admirers, including members of the Lincoln Center Jazz Orchestra, in town for their own gigs at Orchestra Hall.

Other notables who have signed on to perform include brilliant pianist (and festival regular) Jon Weber (profiled last year on MinnPost), local heroes The New Standards and Twin Cities sax master Irv Williams, who’s approaching his 90th birthday.

Here’s the schedule so far:

Thursday, June 18
• Music in Mears Park, TBA.
• Jazz Night Out Club Crawl starts at 8:30, travels to 15 participating venues in downtown St. Paul. Buy a button ($15) through the St. Paul Festival and Heritage Foundation or a participating club, then ride the trolley to the Artists’ Quarter, Black Dog, Bulldog, Camp Bar, Hat Trick, the St. Paul Hotel and more.

Friday, June 19
• Mears Park: 4 p.m. Dakota Combo, 5:15 Terrence Hughes and His Manfredo Fest Tribute Band, 6:45 Irv Williams, 8:30 Allen Toussaint. Free.
• More music at the Artists’ Quarter (Jon Weber) and Hat Trick Lounge (Pooch’s Playhouse, Jack Brass Band, Nikki and the RueMates). Hat Trick starts at 7 p.m., the AQ at 8. Cover charges apply.

Saturday, June 20
• Mears Park: Noon Walker West Music Academy Young Artists Showcase; 1:30 Klondike Kates, 2:30 Southside Aces, 4 The New Standards, 5:30 Paula Berends, 6:30 Alex Han with Jon Weber, 8:30 Esperanza Spalding. Free.
• More music at the Artists’ Quarter (Jon Weber) and the Hat Trick Lounge (Larry McDonough, Atlantis Quartet, George Avaloz, Fat Kid Wednesdays). Hat Trick starts at 7 p.m., the AQ at 9. Cover charges apply.

Mark your calendar now. As June draws near, check the festival’s website for more details.

Pamela Espeland tweets a daily jazz calendar on Twitter and blogs about jazz at Bebopified. Find Twin Cities jazz calendars and more jazz news online at Jazz Police. In the Main Menu at the left, click on Twin Cities. Jazz radio station KBEM 88.5FM posts a live music calendar each week; view it online in the Events menu.