The Boomers will host the Fire after results in the first week of finals followed the form book.
Minor premier Canberra secured the first grand final spot and home advantage for the season decider with a grinding 60-52 major semi-final home win over Bulleen on Friday night.
Townsville booked a spot in the preliminary final by ending Adelaide's title defence on Saturday night.
The Lightning had ended Bendigo's first finals appearance with an 81-73 elimination final victory on Wednesday before succumbing to the Fire.
Both Bulleen and Townsville have never ventured beyond a preliminary final, with the Boomers' season ending there twice and the Fire falling at the same stage once.
"Our club has never made a grand final so it would be fantastic ... it would be a great thing," Bulleen coach Cheryl Chambers said.
While Bulleen is in its 27th WNBL season, Townsville is nearing the end of just its eighth campaign.
"Being a regional team for North Queensland, to make a grand final would be very special," Townsville coach Peter Buckle said.
Chambers said a number of factors contributed to her team's fourth-quarter offensive meltdown against the Caps, during which they scored just four points.
"There's a lot of things, the fact we started so poorly doesn't help, you put pressure on yourself," Chambers said.
She recognised they would face a different challenge from Townsville, who they defeated 76-74 in the final round of the regular season.
"They (Townsville) are nowhere near as big as Canberra, so we would certainly want to change the rebound count and do a lot better job of that," Chambers said.
Buckle was pleased his team's running game returned against Adelaide.
He said the Fire needed to respect everyone on the Bulleen roster rather than just focus on the Boomers' key players.
Photo courtesy of Boomers Media