Martin Emmerson
BBC Newcastle

Glamorgan wanted to bat in the sunshine at Chester-le-Street and duly got their wish. The temperature is already in the mid 20s.

But Jacques Rudolph couldn't take advantage of the conditions as he had his bails trimmed by Chris Rushworth in the 7th over when he was on 13. Rushworth had been bowling a probing line with the batsman playing and missing a number of them before he was out.

Durham are without Keaton Jennings, who will captain England Lions next week. But he is here, having a net session along with Ben Stokes who had returned from Champions Trophy duties, but is not playing.

Glamorgan have also been forced into a number of changes. Keeper Chris Cooke misses this one as a precaution after behind hit on the head in the nets. Cardiff University's Tom Cullen will keep wicket. Will Bragg is ill so Graham Wagg makes his first start of the season too.

Image source, BBC Sport

As I mentioned earlier, 18-year-old batsman Harry Brook is making his Championship debut for Yorkshire today.

He's just got a good luck message from one Yorkshire star he'll be looking to emulate.

However, it's probably going to be a long afternoon in the field for young Harry, Middlesex opening pair Nick Compton and Sam Robson have booked in for bed and breakfast.

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Jimmy's done for Lancashire.

Six overs for the England man, 0-14.

I can't imagine there will be too many spells longer than that today. It's hot. But you know that already.

Ralph Brooker: Ideal outcome: @hantscricket to win this one but the other Jimmy A coming back to form and fitness. A brilliant none-fer.

While we're still waiting for the first wicket in Division One, Worcestershire have just picked up a second of the morning at New Road.

And it's that man Joe Leach again. The skipper sends Sean Dickson's stumps flying for his 35th County Championship scalp of the campaign.

At Trent Bridge, Notts are 30-1 against Leicestershire and Glamorgan are on exactly the same score at Durham.

Howzaaaat?! Rikki Clarke thinks he's found Nick Browne's edge, wicketkeeper Tim Ambrose takes the catch, the Warwickshire players go up - not out.

Ambrose was convinced, Clarke not so much.

Image source, Rex Features

It's been a fruitless opening five overs for James Anderson so far, but it's not really a day for the bowlers is it?

The 34-year-old is playing his first match for Lancashire since injuring his groin on 19 May.

Michael Carberry and Jimmy Adams are looking pretty comfortable for Hants.

Batting day?published at 11:36 British Summer Time 19 June 2017

11:36 BST 19 June 2017

Middlesex 20-0 v Yorkshire

The weather is looking okay at Lord's I guess. Can it be too hot?!

Nick Compton and Sam Robson are enjoying the batting conditions so far - Middlesex are up to 20-0.

A few sides are missing some of their regulars for these matches with England in T20 action against South Africa on Wednesday and the England Lions playing later in the week.

Mason Crane and Liam Dawson are both missing for Hampshire as they are in England's T20 squad but the latter is still sending his support (see above).

Elsewhere, Lancashire are without Liam Livingstone and Haseeb Hameed, Essex are missing Dan Lawrence and Jamie Porter while Nick Gubbins, Tom Helm and Dawid Malan are absent for Middlesex.

In Division Two, Durham are still looking for their first win of the season and will have to do it without Keaton Jennings who is captaining the Lions this week.

But, England's Moeen Ali, Adil Rashid and Steven Finn are all back for their counties after the Champions Trophy.

That's a big wicket for Durham. Glamorgan captain Jacques Rudolph is bowled by seamer Chris Rushworth for 13 to leave Glamorgan 18-1.

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At Trent Bridge Notts opener Jake Libby has edged Leicestershire left-armer Dieter Klein behind for 14. Notts are 21-1.

Kent have also just lost a wicket at New Road, Worcestershire skipper Joe Leach getting Daniel Bell-Drummond caught at slip for a single leaving them 6-1.

Glamorgan have moved to 8-0 at Durham with Jacques Rudolph and Nick Selman at the crease.

James: The weather glorious out on all County Cricket grounds, will we see history with the least number of wickets falling in a day?

Straight drive from Alastair Cook off Rikki Clarke, four runs to get off the mark.

Warwickshire need to get the former England skipper early or he'll fill his boots.

I'd bank on him filling his boots to be fair - it's a day for the batters (batsmen).

Image source, Getty Images

It's been a fairly ropey start to the season for champions Middlesex.

Five games, no wins and four draws has left them 44 points adrift of leaders Essex.

Today they welcome Yorkshire to Lord's in a repeat of last September's thrilling match which saw Toby Roland-Jones' hat-trick seal the title for the London side.

Sam Robson and Nick Compton are currently at the crease for the hosts.

Two overs gone at Chelmsford, two maidens from Keith Barker and Rikki Clarke.

Alastair Cook, off the back of his superb 133 in the One-Day Cup semi-final against Notts on Friday, is in the middle alongside Nick Browne.

It could well be a run fest today.

Image source, Rex Features

As ever, this live text is about you guys getting involved.

Get in touch using #bbccricket on Twitter.

James Anderson is back for Lancashire after a few weeks out with a groin injury.

The England seamer takes the new ball and starts with a maiden.

Good news for England and Lancashire fans.

As ever, there is ball-by-ball radio commentary from all six grounds.

The local radio teams are in place, and BBC Radio 5 live sports extra will be live from Lord's for Middlesex against Yorkshire.

Click on the links at the top of this page to tune in.

There will be a minute's silence first at all grounds to remember victims of the Grenfell Tower fire and terrorist attacks.