Somerset slump to 87-7 after Notts total 448 in their first innings
Lancashire 100-1 at stumps, replying to Warwickshire's 371 all out
Yorkshire earn 80-run first-innings lead over Hampshire at the Ageas Bowl
18 teams split into three divisions of six depending on placings earlier in season
Winners of Division One will be crowned county champions after four rounds of matches
Hampshire 111-6 v Yorkshire 243
The players are back out at the Ageas Bowl and Keith Barker and Lewis McManus have negotiated Dom Bess's latest over. Light permitting, there are 31 overs left in the day.
Somerset 52-3 v Nottinghamshire 448
Luke Fletcher is on fire at the Cooper Associates County Ground!
It's a second wicket of the over, third of the afternoon and 50th in the Championship this season.
He has bowled better deliveries but Tom Abell can't help but glance off his pads into the grateful gloves of Tom Moores.
Division Two: Glamorgan 134 & 20-5 v Essex 320
Another one gone in Cardiff, where Kiran Carlson is stuck on the back foot and bowled through the gate for eight by Sam Cook.
The One-Day Cup winners certainly haven't carried that form on into the return of red-ball cricket.
Somerset 51-2 v Nottinghamshire 448
The change of ball does do the trick!
Tom Lammonby is tempted into playing at one just outside his off-stump from Luke Fletcher and Tom Moores makes a super diving catch to his left to complete the dismissal.
Both openers now back in the pavilion for Somerset and the deficit still 397.
Somerset 51-1 Nottinghamshire 448
So as Tom Abell and Tom Lammonby dig in, Notts have successfully appealed to the umpires to change the ball.
Abell doesn't seem to have a problem with the new one as he crunches a shot through cover for his sixth four as the 50 comes up.
Division Two: Glamorgan 134 & 16-4 v Essex 320
The slope is becoming increasingly slippery for Glamorgan.
Billy Root calls Steve Reingold through for a single but he is beaten by Shane Snater's throw and run out for a duck.
Then Root himself departs in the following over, lbw to Jamie Porter for four.
Another 170 needed to avoid an innings defeat as Chris Cooke joins Kiran Carlson.
Image source, Rex FeaturesSomerset 38-1 v Nottinghamshire 448
Some positive strokeplay from captain Tom Abell has been a good response since tea to Nottinghamshire's imposing total.
But he will know someone in his team will have to go big in the Somerset innings.
Essex strike again in Cardiff with David Lloyd lbw to Sam Cook for a duck. Glamorgan are 6-2 and need another 180 to avoid an innings defeat.
It is tea in Bristol where Gloucestershire are 78-5, replying to Northamptonshire's first-innings total of 327, with Graeme van Buuren 17 not out.
In Division Three, there has been a rain interruption in Leicester where Kent are 148-5, a 281-runlead over the home side. The umpires hope to restart the game at 16:45.
At Lord's, Leus du Plooy has moved on to 84 not out for Derbyshire, who are 156-6, 126 behind against Middlesex.
Young seamer Joseph Sarro has taken two wickets for Sussex at New Road, where Worcestershire are now 180-7 - but bad light has halted play.
Hampshire 109-6 v Yorkshire 243
Image source, RexIt is tea five balls early at the Ageas Bowl as Jordan Thompson's opening delivery of a new over has Liam Dawson leg-before.
It struck him on the rear pad so it doesn't look like he could have many complaints about that one and that rounds off a good session for Yorkshire, who picked up three wickets.
The big scalp was that of James Vince, who top-edged an attempted pull and was caught for 49.
Lancashire 25-1 v Warwickshire 371
Left-arm spinner Danny Briggs is introduced early into the Warwickshire attack as the floodlights come on at Old Trafford.
We are still due 32 overs today, but I would be astonished if they are all bowled.
September usually sees matches start at 10.30 BST, but because this round of matches started in August, we will begin 30 minutes later at 11.00 BST on Wednesday and Thursday. With a bit of common sense, we could surely regain some of the overs that will be lost.
Hampshire 105-5 v Yorkshire 243
Two overs to go before tea at the Ageas Bowl and Lewis McManus is off the mark with three runs from the bowling of Jordan Thompson. Liam Dawson has 10 to his name at the other end.
Division Two: Glamorgan 134 & 1-1 v Essex 320
Are we going to have a two-day game in Cardiff? It's certainly possible after Jamie Porter has Hamish Rutherford lbw for a duck, playing across the line.
The Welsh county are 185 behind and there are a minimum of 35 overs left in the day's play.
Image source, Rex FeaturesHampshire 100-5 v Yorkshire 243
Liam Dawson sweeps Dom Bess for four and a similar shot next ball brings him two and takes Hampshire's total to 100. The home side badly need Dawson and Lewis McManus together at tea.
Division Two: Glamorgan 134 v Essex 320 - tea
Nick Webb
BBC Radio Wales
Essex piled up a sizeable lead over Glamorgan in Cardiff as the eighth-wicket pair of Adam Wheater and Shane Snater recovered momentum for the visitors with a stand of 79.
Wheater (36) rode his luck as he was bowled by a no-ball and then dropped off a caught and bowled chance by Dan Douthwaite, while he should have been given run out on 28.
The aggressive Snater made 48 but was also put down from a return catch by Steve Reingold, whose first Championship spell of off-spin yielded 3-15 either side of lunch.
Earlier, Nick Browne hit a patient first century of the season, while the most fluent innings of the match has been played by Michael Pepper with 63.
Hampshire 93-5 v Yorkshire 234
Image source, RexWhat a beauty by Dom Bess, floated in and turning away to hit the top of Tom Alsop's off stump.
Alsop batted for 141 minutes for his 12 but now Hampshire are in danger of conceding a significant first-innings lead to the visitors.
Lewis McManus is the new batsman, joining Liam Dawson.
What a game Shane Snater is having in Cardiff. Six wickets in Glamorgan's 134 all out and he was last man out for 48 as Essex replied with 320 - a lead of 186.
Gloucestershire are in trouble on 56-5 - 271 behind - in their home game against Northamptonshire with Luke Proctor taking the last two wickets to fall after an excellent new-ball spell by Ben Sanderson.
In Division Three, Kent are on 132-4, a lead of 255 over Leicestershire, who were all out for 109 earlier in the day.
Leus du Plooy is 59 not out at Lord's, but Derbyshire are 116-6, replying to Middlesex's 282 all out.
It is tea at New Road, with Worcestershire 165-4 after dismissing Sussex for 264 during the morning session. Brett D'Oliveira is 37 not out.
Somerset 11-1 v Nottinghamshire 448
The two Toms, Lammonby and his captain, Abell, have faced a testing little spell after the early loss of Steven Davies.
With Luke Fletcher and Brett Hutton charging in and three slips eagerly waiting for an edge, 448 feels like an awfully long way away for Somerset.
Lancashire 6-1 Warwickshire 371
George Balderson will not remember his first innings as a Championship opener for Lancashire with any fondness.
Balderson is trying to work the ball to leg when he is on the pad by Liam Norwell and he's given out for a duck.
Hampshire 86-4 v Yorkshire 243
That's the one Yorkshire wanted.
James Vince tries to pull a short one from Matthew Fisher, but gets underneath it and George Hill runs round to take the catch.
Vince had looked so good on a pitch which isn't ideal for fluent strokeplay, but he misses out on another half-century - and departs with his side still 157 behind.
Hampshire 86-3 v Yorkshire 243
After 81 balls of toil for eight not out, Hampshire's Tom Alsop finds the boundary for the first time in his innings with a reverse sweep off Dom Bess.
He tried it twice before in Bess' previous over without making clean contact, but this time gets it right as he moves into double figures.