Northern Diamonds 218 for 3 (Winfield-Hill 98, Armitage 74) beat Western Storm 186 for 8 (Gibson 52, Levick 2-25, Scott 2-27) by 32 runs
Never before in two years of regional cricket had a team posted more than the 186 for 1 Thunder scored against Sunrisers at Emirates Old Trafford in 2021, and the Diamonds sailed beyond that mark inside only 17 overs under the floodlights.
They took advantage of a short boundary towards the Western Terrace side of the ground and a fast outfield, though captain Armitage hoisted five of her six sixes to the longer leg-side boundary in a 36-ball assault. Winfield-Hill batted with more poise, hitting 21 boundaries in 56 balls.
After inviting the Diamonds to bat in excellent batting conditions, the writing was on the wall for the Storm pretty quickly as Winfield-Hill took Lauren Filer's seam for four fours in as many balls in the second over, moving the score to 21 without loss.
That was the first of 13 double-figure overs, including eight in a row from the start of the 10th over and two of them over 20.
Ireland all-rounder Orla Prendergast was the pick of the visiting bowlers as her seam returned 1 for 32 from four overs, with Armitage caught at deep midwicket late on.
But the Storm, despite only conceding six extras, were unable to gain any control, and their ground fielding became increasingly ragged as the pressure increased.
Winfield-Hill dominated a 58-run opening stand with Leah Dobson (25) before sharing 139 inside 12 overs for the second wicket with Armitage.
Both Winfield-Hill, the beneficiary of a missed stumping chance on 49 as wicketkeeper Nat Wraith fumbled the ball, and Armitage posted their career-best scores in all T20 cricket.
There is an argument to suggest that Armitage's innings was the better of the two given Winfield-Hill was able to ride the wave after a good start in the powerplay. Armitage had to do all her work with the field set back.
Unfortunately for the former, she fell agonisingly short of a maiden T20 century when holing out to deep midwicket off Chloe Skelton's off-spin.
In the opening six overs of the chase, Storm kept themselves up with the rate with 66 on the board, though new ball seamer Scott had struck twice to get rid of Wraith - well caught at deep midwicket by a diving Dobson - and Prendergast caught behind.
That was always going to be the problem for Storm, keeping wickets in hand, and they weren't able to do it despite the Diamonds not being at their best with the ball.
Former England batter Fran Wilson was trapped lbw for 16 reverse sweeping at leg-spinner Levick's fifth ball. Captain Sophie Luff skewed Levick to backward point shortly afterwards before the game-breaker came when Hall had Gibson brilliantly caught on the run by Chloe Tryon at long-on. At 121 for 5 after 13 overs, it was all but game over.
Gibson had been strong through cover and midwicket to give her side a glimmer of hope. But it was extinguished with almost 100 runs still required.
Alex Griffiths and Filer shared a consolatory 43 for the sixth wicket in entertaining fashion, with the former hitting two sixes in 31. But both fell to Glen and Hall in the closing overs.