Elsewhere, Ella McCaughan and Abi Norgrove’s mammoth 147-run partnership helped Hampshire (266-5) to a nail-biting five-wicket win over Essex (265-8).
McCaughan scored 90 and Norgrove struck a personal best 85, and while Hampshire – who lost last year’s final to Lancashire – were taken to the last over, despite Freya Kemp’s vivacious 46, they secured victory with two balls to spare.
Earlier, Jodi Grewcock had led Essex’s innings with a career-high 80 in front of watching England head coach Charlotte Edwards at the Utilita Bowl.
Somerset (179-9) beat Yorkshire (178) in another thrilling finale, albeit in a far lower-scoring affair.
Sophie Luff produced a brilliant match-winning innings of 76 not out from 101 balls as Somerset held their nerve to win by one wicket in Taunton.
Chasing 179 to win, the hosts were deep in trouble on 115-8, only for Luff to lead them to victory against a Yorkshire side making their first ever top tier appearance.
Earlier, the visitors were bowled out for 178 in 33.5 overs as Alex Griffiths and Chloe Skelton took 4-22 and 4-42 respectively. Yorkshire skipper Lauren Winfield-Hill top-scored with 36.
The latest finish of the day came at Edgbaston as Danni Wyatt-Hodge’s dazzling century powered Surrey (389-9) to a 52-run win against Warwickshire (337-9).
Wyatt-Hodge smashed eight sixes and 10 fours in a scintillating 124 from 80 balls, with Jemima Spence (79) and Alice Davidson-Richards (57) adding valuable support as Surrey recovered superbly from 95-4.
Warwickshire’s creditable reply fell short from 101-1 despite the best efforts of Amu Surenkumar (59), Em Arlott (90) and Issy Wong (45) as a burst of top-order wickets from Tilly Corteen-Coleman (3-48) ultimately proved decisive.
Match details supplied by the ECB Reporters’ Network.