Harris blasted 162 from 69 balls for Wests against Sandgate-Redcliffe after earlier producing 68 from 49 balls in the early game against Gold Coast as the T20 aspect of the competition got underway.
The hard-hitting allrounder was near unstoppable as she pummelled 17 fours and 12 sixes against the Gators as Wests put on 2-210.
Her remarkable innings broke her own record for the highest T20 score in the Katherine Raymont Shield.
Reigning Kath Smith Medallist Tess Cooper hit 99 from 61 balls for Sandgate-Redcliffe in reply as they fell short, in spite of a more than respectable total of 4-180.
In the first game, Harris showed signs of what was to come with her knock of 68 at the top of the order ensuring Wests chased down the Gold Coast total of 2-121 in just 15 overs.
She has now scored 428 runs at 85.6 from her six matches so far this summer, including a century and three half centuries.
It was a day of eye-catching batting efforts, with Georgia Redmayne producing a dashing 72no for the Gold Coast in their win over University of Queensland. The newly signed WBBL Heat player hit 10 fours and three sixes in her 35-ball innings.
Another WBBL Heat player, Valley batter Mikayla Hinkley, showed her class with 94 not out off 63 balls against newcomers Sunshine Coast.
In-form Wynnum-Manly/Redlands batter Chelsea Gan (66) was the linchpin of her team's innings against Ipswich/Logan but the Hornets proved too strong with the Johnston cousins, Ellie and Ruth, continuing their sold batting form across the day.