The history of the current channel 58 began November 22, 1996 with a construction permit granted to KM Communications to serve Sierra Vista and Tucson on analog channel 58. The call letters were originally KAUC, but in August 1997, the station changed their call letters to KWBA to reflect their affiliation deal with The WB; the former superstation feed of Chicago's WGN-TV served as Tucson's "de facto" affiliate of The WB until KWBA signed on. KWBA began broadcasting under Program Test Authority on January 5, 1999 and was licensed on May 24, 1999. Also in May 1999, KM Communications transferred the station to Cascade Broadcasting Group. It switched to The CW on September 18, 2006. KWBA is one of the former WB affiliates to retain its "WB" callsigns after affiliating with The CW (KSWB-TV San Diego, which became Fox on July 31, 2008 was the other, along with WSWB-TV in Scranton–Wilkes-Barre, although "SWB" doesn't mean its former WB affiliation, but its broadcast area).