The Stockton Symphony’s 89th season begins with performances of ‘S Wonderful: Gershwin and Kevin Cole. Maestro Peter Jaffe conducts an all-Gershwin program with a 69-piece orchestra, performing compositions ranging from Porgy & Bess to Rhapsody in Blue, as Kevin Cole—“the best Gershwin pianist in America today” (Chicago Tribune)—shows how it’s done.