As Bob Hunt prophesied (see 17:20 entry), that's your lot for the day in Bristol. Seems wrong somehow that bad light should end play at a ground called Brightside.  

It's been an even contest with Durham fighting back well following half-centuries by Chris Dent (59) and Will Tavare (61). Paul Collingwood was arguably the pick of the Durham attack, taking 2-29 from 10 overs, and he also took three catches to underline his continuing worth to the side at the age of 40.

Yorkshire look for positive finishpublished at 17:44 British Summer Time 21 April 2017

17:44 BST 21 April 2017

Hampshire 258-3 v Yorkshire (80 overs)

The delay for bad light is brief at the Ageas Bowl and David Willey takes the new ball for Yorkshire after the teams return to the middle. 

Image source, Rex

Bad light has become a common theme in this text commentary, which is a real shame, because we've had some great action around the nine county grounds today. Off they go at New Road, where Worcestershire have fought back well after a poor batting performance. 

Ben Duckett is 45 not out for Northants, with partner Steven Crook on two. Josh Cobb was the last man dismissed, lbw to Ed Barnard for seven, three balls before the umpires called a halt.

Westwood wears down Surreypublished at 17:28 British Summer Time 21 April 2017

17:28 BST 21 April 2017

Warwickshire 285-4 v Surrey (78 overs)

Ian Westwood has lost some of the fluency he had earlier in his innings, it's taken him 12 overs to go from 140 to 150, but this has been an invaluable knock for his side. He reaches 150 with a single off Jade Dernbach and has so far faced 216 balls and hit two sixes and 21 fours. Tim Ambrose is busy at the other end, hitting four boundaries in his 20 not out off 21 balls so far.

There are 16 overs remaining at the Ageas Bowl as the umpires lead the players off. This has definitely been Hampshire's day so far, thanks largely to an unbroken stand of 101 between James Vince and Sean Ervine. Vince now has 137 to his name, with Ervine on 39, and Yorkshire haven't managed a wicket since the 27th over.

Elgar reaches half-centurypublished at 17:22 British Summer Time 21 April 2017

17:22 BST 21 April 2017

Lancashire 109 v Somerset 101-4 (35.3 overs)

Somerset are just a few runs short of a first-innings lead as South Africa batsman Dean Elgar takes a single off Ryan McLaren to reach a 111-ball half-century, featuring seven fours. Jimmy Anderson is now taking a breather with the impressive figures of 1-19 from 14 overs.

Bob Hunt
BBC Radio Gloucestershire

They've gone off for light at Bristol just when Durham began to get on top. Keaton Jennings dismissed  Phil Mustard and Craig Miles with successive deliveries, both caught by Paul Collingwood in the slips.

Mustard had done well against his former employers, having put on 64 with Jack Taylor, and Taylor is still there with a trademark quickfire 41.

I can't see them coming back on this evening, so the day will end with Durham perhaps the slightly happier of the two sides.

Alex Winter
BBC Radio Northampton sport

It's been a bowler's day at New Road. Northants have been trying to counter-attack, going along at a good lick, hoping to flick over some runs before the inevitable seemingly happens. As a consequence, there have been two batsman caught at point and Richard Levi should have been caught via a leading edge before he was lbw.

So where will this day end? Probably with bad light preventing many of the 25 overs still to be bowled, it's very gloomy here. Sunny weather tomorrow and potentially a better batting day, but can Northants get there in any kind of shape? Ben Duckett is 43 not out.

Fabian Cowdrey
Former Kent all-rounder

The umpires have been checking their watches enthusiastically as players limber up on the side of the pitch.

Fortunately, they have said play can resume, with the hosts 214-8. An exciting conclusion to the day's play awaits us here at the St Lawrence Ground.

It's hard to believe that Notts were 88-5 at one stage of their innings, as Riki Wessels takes them to maximum batting points by clobbering Stiaan van Zyl for the seventh six of his innings. He's clearly having no problems seeing it, on 186 not out, but the umpires nonetheless decide that the light isn't good enough for play to continue. A real shame for the spectators in the ground.

The poor light has spread from London to the South East, where Kent and Derbyshire have been forced from the pitch at the Spitfire Ground. 

Adam Rouse (21) and James Harris (5) are the two batsmen to walk off, while Will Davis and Luis Reece have three wickets each for the away side.

Westwood clears the ropepublished at 16:51 British Summer Time 21 April 2017

16:51 BST 21 April 2017

Warwickshire 260-3 v Surrey (71 overs)

Before this match, Warwickshire opener Ian Westwood had not managed a single six in 155 first-class appearances. Now he has two to his credit, both off Surrey seamer Jade Dernbach, the second pulled away over the short leg-side boundary. 

Hampshire collect their first batting bonus point as James Vince hits two successive fours off David Willey at the Ageas Bowl. Yorkshire would very much like to see the back of the Hampshire skipper, who can be hard to keep in check when his confidence is high. It's 16 fours in total for the right-hander, whose partnership with Sean Ervine for the fourth wicket is now worth 55. Floodlights now on.

Image source, Rex Features

Northants have survived a hat-trick attempt from Worcestershire's Joe Leach.

The right-armer dismissed Rob Keogh and Adam Rossington in successive deliveries but Richard Levi was able to negotiate the hat-trick ball.

He's alongside England batsman Ben Duckett (36) in the middle as Northants look to rebuild.

It's become a little murky overhead at the home of cricket, prompting umpires Paul Baldwin and Ian Gould to take the players off the field. Middlesex opener Sam Robson is 144 not out, with 24 fours so far in his 196-ball innings, and Stevie Eskinazi has a single to his name.

Let-off for Elgarpublished at 16:34 British Summer Time 21 April 2017

16:34 BST 21 April 2017

Lancashire 109 v Somerset 71-4 (24 overs)

Now how significant will that prove to be? Dean Elgar is dropped by fellow South African Dane Vilas after Jimmy Anderson produces one to find the edge. It's a tough chance at third slip, but you don't want to be giving chances to batsmen with seven Test centuries to their credit.

Anderson's frustration turns to delight, though, in his latest over as he has Steven Davies caught behind by Alex Davies for one with one that leaves the left-hander off the pitch.