The Royal Norfolk Show opens today, with 100,000 visitors expected to flock to the event over the two days.

Showgoers are being advised to avoid the Longwater exit off the A47 because of large queues.

Marcus Hammond from SEP Events, the events car park company, said there is heavy traffic at the Sainsbury's roundabout and is urging drivers not to come off there, but to carry on, coming off at the Easton exit.

Traffic is still backed up with a solid queue on both lanes of the westbound A47 stretching past the Thickthorn junction and queues of more than 50 minutes.

Eastbound traffic no the A47 is also queuing as far as North Tuddenham.

Earlier this morning there was a large queue in Norwich's Dereham Road out towards the showground, but reports are this is easing, however the roundabouts either side of the A47 are still heavily congested.

Temporary traffic lights have been put in place at the Longwater roundabout to help manage the traffic flow.

There have been a few showers early this morning, but it is expected to remain dry with sunny spells for the rest of the day.

Gates opened at 8am today, with the show itself opening at 8.30am, and to help showgoers get to the ground more smoothly, a traffic plan has been drawn up with five new traffic routes.

Colour-coded entry routes are being used and the traffic management plan includes the installation of temporary traffic lights on the Longwater roundabout on the A47 slip road to improve the flow of vehicles around the busy junction and also some one-way routes.

The aim is also to help ease congestion on busy country roads.

Traffic approaching the showground will be sign-posted on to five routes – red, brown, purple, blue and yellow.

As the Royal Norfolk Show got underway, chief executive John Purling said: 'It is a fantastic event and around the showground there is great enthusiasm and great zeal. The show has great relevance to Norfolk life and provides two great days of entertainment.'

Mr Purling said an estimated �40-50m was put into the local and national economy from the show.

'It is a very significant sum of money and the show plays a really important part in local life.'

He said he hoped showgoers would find getting to the ground easier than in previous years.

'We have completely revised the traffic routes and simplified and it and made it more efficient. We recognised where the bottlenecks were and we are confident it will work well. We hope everyone follows the signs and gets here and has a great time.'

The weather is expected to be warm and dry for the rest of the day, but tomorrow there could be some thundery showers around lunchtime.

Dan Holley, forecaster at the University of East Anglia's Weatherquest, said: 'We have had a couple of showers this morning but they seem to have cleared off to the east.

'I think the bulk of today should be dry with sunny spells bit with quite a bit of cloud coming and going throughout the course of the day. Temperatures should be about 22 and 23 degrees and there is a light south-westerly wind so it should be quite a pleasant day there.

'Tomorrow it will be starting dry in the morning, but there could be some mist and fog first thing.

'The cloud will tend to increase throughout the morning and by late morning, lunchtime we could get outbreaks of thundery rain which could clear by mid-afternoon. It should then be an improving picture with some sunny spells and it will still be quite humid around 22 and 23.'

First will be running bus service 100 directly to and from the showground today and tomorrow. At peak periods buses will depart every 10 minutes from Norwich Rail Station via St Stephens Street, dropping visitors at the showground gate.

Combined bus and show admission tickets can be bought on the bus.

Konectbus will run an hourly service to the show from Dereham and from Attleborough and Wymondham, via Norwich Bus Station. For times and prices visit www.konectbus.co.uk

There is no shuttle bus service between Costessey Park and Ride and the showground this year.

A number of surrounding roads will be restricted to one-way traffic on show days. These are:

Dereham Road, Easton (one-way westbound), Marlingford Road, Easton (one-way westbound from the exit of the Yellow car park), Bawburgh Road, Easton (one way from the Easton College entrance south to Marlingford Road) and Long Lane, Bawburgh (one-way southwards from the entrance to the Blue and Green car parks onto Hart's Lane junction).

See our website for reports, pictures and videos with a flavour of all that is happening at the show.