Play has now finished for the day. Click the links below to read the match reports.Nottinghamshire v HampshireSomerset v WarwickshireWorcestershire v MiddlesexYorkshire v SussexDerbyshire v LeicestershireEssex v LancashireGloucestershire v GlamorganSurrey v Northants
BBC Somerset's Anthony Gibsonat Taunton:
"A sigh of disappointment went round the County Ground when Marcus Trescothick was caught behind for 87 off debutant Mark Adair, so missing out on his third consecutive century.
"But James Hildreth's wristy stroke play has been a delight as usual in his unbeaten 75, with Jim Allenby, still looking for his first Somerset century, providing some lusty blows in support, on 29.
"Jeetan Patel has been the pick of the Warwickshire bowlers, on a pitch which may be offering slightly more to spin than to seam, but is still a very good batting track."
Surrey and Northants will have to try again tomorrow after play was abandoned for the day at The Oval because of persistent rain in the capital.
After a further inspection at 15:30 BST, the umpires decided it was too wet to get under way.
Rob Taylor and Zak Chappell shared an unbroken partnership of 71 to save Leicestershire from total collapse against Derbyshire.
They each had 33 not out at tea after left-arm paceman Mark Footitt took 6-69 for the home side earlier in the day.
Opener Ned Eckersley made an aggressive 50 during the morning session and Aadil Ali again demonstrated his potential with 37 before falling to Tom Milnes.
BBC Radio Nottingham's Dave Bracegirdle at Trent Bridge:
"Billy Root made an attractive 37 on his county debut for Nottinghamshire.
"The left-handed younger brother of Yorkshire and England's Joe Root appeared unfazed by the pressure of the situation and was quick to punish any width as he struck six boundaries in his 74-minute innings.
"He helped add 82 for the fifth wicket with Riki Wessels before a thickish edge off Gareth Berg was taken at first slip, after rebounding out of the hands of James Vince."
BBC Sussex's Adrian Harms at Headingley:
"Sussex have fought back since lunch at Headingley, claiming three wickets for the addition of 39 runs before rain intervened and an early tea was taken.
"As so often for Sussex, Steve Magoffin led the fightback accounting for Andrew Gale and Jonny Bairstow in quick succession, whilst Gary Ballance, having done all the hard work, played a poor shot to a wide delivery to be caught at backward point.
"With 48 overs left in the day it could be a long final session."
Lancashire's hopes of pipping Surrey to the Division Two title suffered a setback when the opening day of their game against Essex at Chelmsford was washed out.
The decision to abandon play for the day was taken shortly after 14:00 BST. England skipper Alastair Cook is set to play for Essex in the match.
BBC Radio Leeds' Dave Callaghan at Headingley:
"An important match for Sussex, who started needing nine points to avoid relegation.
"Chris Jordan quickly removed Adam Lyth for three and Alex Lees fell to Lewis Hatchett for 29, but then Gary Ballance and Andrew Gale scored freely in an unbroken 51-run partnership in which they both found the boundary with regularity."
Mark Footitt bowled an inspired new-ball spell in what is likely to be his final Championship appearance for Derbyshire.
The left-armer bowled Leicestershire's Angus Robson and Dan Redfern with successive deliveries and finished the morning session with 4-38 from 10 overs.
His final victim was Ned Eckersley, who went for exactly 50, made from only 46 balls, with eight fours.
BBC Radio Nottingham's Dave Bracegirdle at Trent Bridge:
"Three early wickets for Fidel Edwards more than justified James Vince's decision to insert the home side on the opening morning of Hampshire's vital match against Nottinghamshire.
"Scrapping for First Division survival, Hants got off to the perfect start in a must-win match, as Edwards removed Brendan Taylor and he followed that with the wickets of Jake Libby and Samit Patel.
"An unbroken stand of 56 between Steven Mullaney and Riki Wessels turned the session around, though, with Wessels passing 1,000 runs for the season when he reached 20."
BBC Somerset's Anthony Gibson at Taunton:
"A satisfactory morning for Somerset, which would have been a whole lot better but for a wild heave from Tom Cooper, which left his middle stump lying on the ground off the last ball before lunch.
"Marcus Trescothick is still there on 50, his 11th score of 50 or more in the County Championship this season, and the wicket looks to be as placid as everyone was expecting.
"This was a good toss for Somerset to win, on a blustery, distinctly autumnal day."
BBC Radio Gloucestershire's Bob Hunt at Bristol:
"There was always going to be a danger of 'after the Lord Mayor's show' for Gloucestershire after their One-Day Cup win, and it has been a slow morning.
"Glamorgan win the toss and surprisingly chose to bat with a late start in damp conditions.
"The away side managed just 22 in 14 overs as they negotiated some movement and pace from David Payne and James Fuller."
The start of three games in the final round of Championship fixtures have been delayed by rain. There will be no play before lunch at The Oval, where Surrey need a maximum of 17 points against Northants, to make certain of the Division Two title.
It is a similar story for rivals Lancashire, who are waiting to begin their game against Essex at Chelmsford, and in Division One, the umpires are to carry out a 13:10 BST inspection where relegated Worcestershire's game against Middlesex has yet to get under way.
Commentaries available on this page: (scroll through the live coverage tab to select your game)
All matches to start at 10:30 BSTFull scorecards available here
Nottinghamshire v Hampshire - BBC Radio Nottingham
Somerset v Warwickshire - BBC Radio Bristol/ BBC Somerset
Yorkshire v Sussex - BBC Radio Leeds
Derbyshire v Leicestershire - BBC Radio Derby
Surrey v Northants - BBC London 94.9
Worcestershire v Middlesex - BBC Hereford and Worcester
Gloucestershire v Glamorgan - BBC Radio Bristol/ BBC Radio Gloucestershire
Essex v Lancashire - BBC Essex