Here's what they are playing for....published at 13:57 British Summer Time 27 September 2020
Image source, Rex FeaturesSummary
Southern Vipers all out for 231 after being put in by Lauren Winfield-Hill
Georgia Adams top scores with 80, reaching 500 Trophy runs
Northern Diamonds all out for 193 in 42,2 overs
Sterre Kalis makes 55, her third successive half century
Charlotte Taylor takes 6-34 from her 10 overs for Vipers
Southern Vipers also won every game in group stage
Here's what they are playing for....published at 13:57 British Summer Time 27 September 2020
Image source, Rex FeaturesHow the Heyhoe Flint Trophy came aboutpublished at 13:55 British Summer Time 27 September 2020
Southern Vipers 231 v Northern Diamonds - yet to bat
The Rachael Heyhoe Flint Trophy was created to fill the domestic cricket gap created by the ending of the Kia Super League last summer, and the cancellation of the inaugural season of The Hundred because of Covid-19.
With 25 players, not contracted by England, having been awarded £1,000 a month regional retainers, they needed games to play in.
The one-off competition was named after Baroness Heyhoe Flint, skipper of England's World Cup winning team in 1973, who passed away in 2017.
Image source, Getty ImagesImage caption, Baroness Heyhoe Flint, with Charlotte Edwards and Ebony Rainford-Brent in 2009
Watch the best of Adams' 80 for Southern Viperspublished at 13:50 British Summer Time 27 September 2020
Skipper Georgia Adams was once again the mainstay of the Southern Vipers innings - and reached 500 runs in the RHF Trophy before she was caught on the boundary. Here are some highlights from her innings.
Media caption, Rachael Heyhoe Flint Trophy: Georgia Adams hits 80 for Southern Vipers
Vipers set the targetpublished at 13:47 British Summer Time 27 September 2020
So, is 231 all out enough for Southern Vipers?
It looked like they would get far more than that when they were 150-1 at the start of the 31st over, but Northern Diamonds did really well to rein them in.
Spinner Katie Levick - who really does give it a rip - was the pick of the bowlers with 3-49.
The highest score made by Northern Diamonds when batting second in the Rachael Heyhoe Flint Trophy is 229-8 - so they are going to have to better that to win this game.
WICKETpublished at 49.5 overs
Taylor c Armitage by Gunn 7 (Vipers 231 all out)
A couple of wides by Jenny Gunn are free runs for Southern Vipers and number 11 Lauren Hill then lofts the ball away for four.
The next delivery is drilled back down the pitch and Gunn pays the price for her sticking out her left boot. The facial grimace tells the story.
Gunn is made of tough stuff, though, and she is soon back on her feet to end the Vipers innings as Charliotte Taylor hits the penultimate delivery of the innings straight to deep mid-wicket.
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End of twitter postVipers 221-9published at 49th over
Taylor 7, Bell 0
Charlotte Taylor thumps a single to mid-off to end the over - and there is one to go, to be bowled by Jenny Gunn.
Beth Langston finishes with 1-35 from her 10 overs.
WICKETpublished at 48.5 overs
Windsor run out 37 (Vipers 220-9)
Charlotte Taylor and Emily Windsor exchange singles from the first three balls of the penultimate over.
Windsor carves the next up in the air but it falls into a gap on the off-side and she is able to come back for two.
It is her last scoring stroke as she tries to pinch another singe but Sterre Kalis' direct hit at the bowler's end brings her valuable innings to an end.
Vipers 215-8published at 48th over
Windsor 34, Taylor 4
A change of bowling as Lauren Winfield-Hill summons Jenny Gunn to bowl her eighth over - she has 0-20 so far.
Charlotte Taylor can make nothing from the first five deliveries, but a single to long-on denies Gunn a maiden.
A great over for Diamonds, though.
Vipers 213-8published at 47th over
Windsor 33, Taylor 3
Here comes Beth Langston again and Charlotte Taylor collects one with a square drive which Jenny Gunn does well to prevent running for four.
Langston tries a slower ball to Emily Windsor, but it's a full toss which is clubbed back over her head - Windsor doesn't time it properly, but it has enough roll-speed to reach the rope.
It's a no-ball on height, but Windsor can only manage a single from the free hit, and Charlotte Taylor can make nothing of another 'slowie' for the final delivery.
Vipers 206-8published at 46th over
Windsor 28, Taylor 2
A leg-side wide by Hollie Armitage sees the Vipers total reach 200 and Emily Windsor strikes a welcome boundary as the spinner overpitches.
Windsor pushes for one to mid-wicket, but that doesn't secure the strike for the next over as Charlotte Taylor picks up a single to extra cover from the final delivery.
Vipers 197-8published at 45th over
Windsor 23, Taylor 1
Beth Langston is going through her variations and a back of the hand delivery costs her a wide.
She tries it again and Beth Windsor pushes it away for a single, but that's the only run off the bat in the over.
Vipers 193-8published at 44th over
Windsor 22, Taylor 1
How does Beth Windsor play this now?
A single gives the strike to Charlotte Taylor, who thumps a full toss through the covers for one to end the over.
Hollie Armitage now has 2-24 from her seven overs.
WICKETpublished at 42,6 overs
Monaghan c Heath b Langston 1 (Vipers 191-8)
Southern Vipers will struggle to get to 220-230 now as Alice Monaghan tries to drive Beth Langston and edges a low catch to the keeper.
It's a deserved reward for the right-arm seamer and the bespectacled Charlotte Taylor is the new batter.
WICKETpublished at 42,1 overs
Norris run out 5 (Vipers 188-7)
Tara Norris plays towards point and with Emily Windsor sprinting towards her, sets off belatedly for a single.
Linsey Smith's throw to Beth Langston is accurate and she whips off the bails to run the left-hander out,
The Vipers have gone from 150-1 to 188-7 in the space of 11 overs.
Vipers 187-6published at 42nd over
Windsor 19, Norris 5
Hollie Armitage sends down a full toss which Tara Norris pulls towards mid-wicket and she is relieved to see it bounce just in front of the boundary fielder as she skips through for one.
Emily Windsor picks up a run of her own before a well-flighted delivery goes past the edge but Norris shoves her foot back to prevent a stumping.
Vipers 184-6published at 41st over
Windsor 17, Norris 3
Beth Langston is back into the attack - she's the quickest of the bowlers on show and goes past the outside edge of Tara Norris' bat with her first two deliveries.
Norris makes contact to add a single and Emily Windsor square cuts the next for four - Gordon Greenidge and Robin Smith would have enjoyed that one.
A mis-field by Linsey Smith gifts Windsor another run to end the over - Langston wouldn't have been amused by that one.
Vipers 178-6published at 40th over
Windsor 12, Norris 2
Again, only a handful of runs off the over.
So, 10 overs left for the Vipers. It's also the end of the powerplay, just 11 runs from those 30 balls.
What a collapse this has been. Five wickets for 20 runs!
Postpublished at 12:53 British Summer Time 27 September 2020
We may have mentioned that it's quite chilly at Edgbaston....
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End of twitter postVipers 176-6published at 39th over
Windsor 11, Norris 1
Another over of spin ticks through. One from it.
Just 10 runs from the last 24 deliveries for the Vipers.
Katie Levick and Hollie Armitage have been fantastic with the ball.
Vipers 175-6published at 38th over
Windsor 10, Norris 1
Emily Windsor and Tara Norris are struggling to pick leg-spinner Hollie Armitage.
Another economical over, three from it.