The Blaze made it back-to-back wins to go top of the Charlotte Edwards Cup table while South East Stars got off the mark with their first victory.
A burst of six wickets for the addition of only 32 runs paved the way for the Stars to defeat winless Sunrisers by four wickets at Lord’s, skipper Bryony Smith top-scoring with 38.
Blaze restricted Thunder to 117-6 at Old Trafford and looked set to cruise home after Tammy Beaumont’s swashbuckling 38 from 21 balls.
However wickets tumbled and in the end Blaze stumbled home by three wickets in the 16th over.
Kate Cross’ late 22 from 15 hauled Thunder to 117 but Marie Kelly contributed 16 to a Blaze opening stand of 56 from just 32 balls before being bowled by Sophie Ecclestone (2-18) with Beaumont being trapped lbw without another run being added.
Nat Sciver-Brunt and Georgie Boyce added a rapid 32 from 19 balls but 88-2 became 113-7 before Sarah Glenn (17 not out) steered them home with 28 balls to spare.
Earlier Sunrisers rallied from 64-6 to post 132-8 but it was not enough as Stars got home with an over to spare, having smashed 61 in the powerplay.
After a solid start from Mady Villiers (16) and Dane van Niekerk (17) South East Stars claimed six wickets in 33 balls to take charge.
Joanne Gardner (25) was run-out after being sent back by Eva Gray following a 48-run partnership for the seventh wicket but Gray stayed firm to the close, finishing with a fine 34 from 24 balls.
Paige Scholfield finished with 3-24 from her four overs, bowling van Niekirk as well as having Cordelia Griffith (18) caught by Tash Farrant.
In a blistering start Smith and Alice Capsey (24) put on 30 for the second wicket before Phoebe Franklin (30) joined Smith for another 31 for the third wicket and despite wickets tumbling they got home on 135-6 with six balls remaining.