Ben Stokes out for 5 on return from injury for Durham
Brendan McCullum hits 87no in last Middlesex appearance
South leaders Glamorgan beat Surrey by 9 wkts
Worcs bowled out for 53 in loss at Lancs
Birmingham top North group after win at Leics
Durham 37-2 (4.2 overs) v Yorkshire 134
I have done it again! Just as I was praising Durham, they lose their second batsman in eight balls as Azeem Rafiq has the Jets opener caught in the deep.
There is a menacing cloud lurking and the Duckworth Lewis target has shot up to 34, as those two scalps for the Vikings.
Durham 26-1 (3.1 overs) v Yorkshire 134
Mark Stoneman races to 18 off just 12 balls but Phil Mustard falls foul of a short ball from Tim Bresnan and is dismissed for just eight.
It brings England and Durham allrounder Ben Stokes to the crease, to mild applause of the crowd at Chester-le-Street.
He sends his second ball to the mid-wicket boundary. We could be in for a fun evening...if the weather holds.
Derbyshire 102-8 (17.1 overs) v Notts
It's not going too well for Derbyshire and the wickets keep on tumbling.
This time it's Tom Poynton. He's caught at deep square leg by Greg Smith off the bowling of Harry Gurney.
Notts are coasting along quite nicely here as Derbyshire struggle to deal with their bowling line-up.
Leicestershire 94-6 (17 overs) v Birmingham Bears
Birmingham Bears' bowlers have been frugal this evening, making it difficult for Leicestershire to set a target.
Oliver Hannon-Dalby only goes for six off his third over and has figures of 1-10 from his 18 balls. A remarkable economy rate in T20 cricket.
Essex v Hampshire 113-6 (17.1 overs)
Essex continue picking up important wickets as Napier grabs his second of the evening, clean bowling danger man Darren Sammy
Lancashire 149-5 v Worcestershire 0-1 (0.1 overs)
Well that's quite a start behind the stumps for youngster Tom Moores as Tom Kohler-Cadmore gloves a ball banged in short by Nathan Buck. He's a very dangerous customer in this form of the game and Lancashire will be thrilled to see the back of him.
Middlesex 145-5 (15 overs) v Kent
Image source, Rex FeaturesHe's 40 years old but Darren Stevens remains one of the canniest cricketers on the county circuit and that's a superb effort by him - 4-31 from his four overs. John Simpson was his final victim, caught by Alex Blake. Brendan McCullum is there on 57 as Nick Gubbins joins him in the middle.
Glamorgan 0-1 (0.3 overs) v Surrey 110
Ouch, that wasn't the way it was meant to go for Glamorgan. David Lloyd goes off the third ball.
Sam Curran is the man to do the damage and Ben Foakes takes the catch to send Lloyd on his way.
That's a big blow for Glammy. Lloyd hit a tremendous 97 not out against Kent last week. Game on?
Middlesex 136-4 (13.1 overs) v Kent
Kent have fought back well at Canterbury, with James Fuller the latest to go, bowled by Darren Stevens for a single. The dangerous Brendan McCullum is still there, though, and he reaches a 34-ball half-century with two runs off James Tredwell.
Image source, Rex FeaturesEssex v Hampshire 98-5 (15 overs)
Image source, Rex FeaturesThe Chemlsford crowd are in full voice as fan favourite Ravi Bopara bowls Liam Dawson and the dangerous Shahid Afridi in his second over.
Two overs earlier Graham Napier had bowled debutant Joe Weatherley for a modest 18 off 17 balls.
Darren Sammy has come to the crease, with Hampshire needing some gutsy blows from the West Indian batsman if they're going to post a competitive total.
Leicestershire 80-6 (14.3 overs) v Birmingham Bears
That's the wicket Birmingham Bears wanted!
Lewis Hill and Umar Akmal threatened to get Leicestershire back into the contest with a stand of 53 for the fifth wicket.
But both end up falling in the space of five balls, with Hill caught behind off Mark Adair before Pakistani dangerman Akmal can only hole out to Ateeq Javid off fellow spinner Jeetan Patel.
Lancashire 149-5 (20 overs) v Worcestershire
Debutant Tom Moores boosts the total with two successive boundaries in the penultimate over, one drilled down the ground from a full toss and one from a streaky edge, and seamer Joe Leach finishes his four overs with 2-34.
Alviro Petersen starts the final over with a single off Matt Henry, but his 19-year-old partner is unable to get bat on ball from the next three. Moores then slashes a single and Petersen manages to add two from the last delivery to reach 68 not out. is that enough for Lancashire?
Durham v Yorkshire 134 (19.3 overs)
Paul Coughlin - who went for 22 runs in his first over - grabs the final Yorkshire wicket as he has Steven Patterson caught behind.
It was pretty dismal innings from the Vikings, with only Alex Lees (43), Jack Leaning (48) and Tim Bresnan (19) making double figures.
Chris Rushworth starred, taking 3-14, as Usman Arshad, Paul Coughlin and Scott Borthwick all picked up two scalps each.
Surrey 110 (19.2 overs) v Glamorgan
Well that's it for Surrey's innings and Glamorgan have shown why they've been so formidable in the T20 Blast this season.
Chris Cooke and Dale Steyn combined for the Welsh county as they made easy work of skittling Surrey out.
Surrey haven't left much in the way of a chase for Glamorgan. Given their batting performances this season, they shouldn't have too much trouble reaching 111 if they keep their top order intact.
Middlesex 119-3 (11.1 overs) v Kent
The Stevens-Tredwell combination does the trick again for Kent as Paul Stirling's eight-ball cameo is brought to an end.
James Franklin is next man in for Middlesex, joining fellow New Zealander Brendan McCullum, but is run out by Fabian Cowdrey's direct hit at the start of the next over.
Durham v Yorkshire 139-9 (19 overs)
Yorkshire's last hope of making a defendable total trudges back to the pavilion as Usman Arshad has Jack Leaning caught at short fine-leg by Chris Rushworth.
Essex v Hampshire 80-2
The loss of Michael Carberry and Tom Alsop has stopped Hampshire's momentum.
Debutant Joe Weatherley has made a run-a-ball 13 thus far, while Liam Dawson - unbeaten on 18 - has scored the only boundary since the pair came to the crease.
Surrey 97-8 (17 overs) v Glamorgan
It's almost as if Dale Steyn didn't want to be outdone by Chris Cooke's part in five of the eight wickets Glamorgan have taken off Surrey.
His final stint bowling for Glammy ends with yet another wicket as he bowls Sam Curran, much to the delight of the Cardiff crowd.
Surrey have limped their way to 97, but look a depleted side. Glamorgan are certainly showing their ambition in this tournament this season.
Leicestershire 50-4 (10.5 overs) v Birmingham Bears
Leicestershire finally get 50 up, but it's taken until the 11th over to get there.
You would think they might need to go an 10 an over from here on in to give themselves something to defend.
Lancashire 124-5 (16.2 overs) v Worcestershire
Lancashire are losing their way a little as Jordan Clark holes out at deep-mid-wicket, two overs after skipper Steven Croft was caught at cover - both victims of Joe Leach. Tom Moores walks out to play his first innings for the Red Rose county, once coached by his father Peter. Alviro Petersen is still there with 58.