Trains on the National Express East Anglia line have been cancelled and trains running slower because of the heat.

South westerly winds and blue skies helped make Norfolk one of the nation's hottest spots as the country bathed in sunshine today.

And amid the sun cream and sun glasses there were tales of train travel disruption, with power cables being held responsible for delays and cancellations.

Rail passengers in East Anglia line also felt the effects of the heat, with a number of trains cancelled and running slower.

Services on the Norwich to London line are affected, and other services in and out of Essex are not running. There were also further cancellations and delays through theis evening because of the overhead wire problems.

National Rail imposed restrictions meant before 11am and after 5pm today there was a maximum speed of 80mph, while between 11am and 5pm a maximum speed of 60mph was imposed. The normal maximum line speed is 90mph.

Of more than 2,000 National Express East Anglia trains scheduled to run around 35 were subject to cancellation or amendment – all in the off-peak period.

A Network Rail spokesman said yesterday: 'Network Rail is currently investing more than �200m to replace the overhead power lines between London, Chelmsford and Southend.

'The old system was installed in the 1940s and 50s and despite having performed well for many decades, it is liable to expand in extreme hot weather causing the overhead lines to sag. Running trains at full speed in these conditions increases the risk of damage to the overhead power equipment.

'The new system being installed is much more reliable and allows us to adjust the tension of the wires to compensate for extreme temperatures, removing the need for speed restrictions in hot weather.

'Whilst we apologise for the small number of services which have been amended today, the overwhelming majority of passengers will be unaffected.'

Topping temperatures in the region was Santon Downham just over the Suffolk border, near Thetford, which registered 32.5C (90.5F), and across many parts of Norfolk thermometers read over 30C (86F).

However, severe weather warnings were being given last night, with heavy thunderstorms predicted due to an area of low pressure that was set to move in to the region.

Chris Bell, a weather forecaster at Norwich-based Weatherquest, pointed to the predominance of south westerly winds, which warm up as they travel across land from the sea, in the current hot spell as being the reason Norfolk has felt the heat more than other areas.

'It's probably been the warmest days in the last few years around this area - normally it's around 20C this time of year, and when you have these winds Norfolk is often one of the hottest parts of the country.'

Both the 9pm and 9.30pm trains leaving Liverpool Street station in London to Norwich tonight have been cancelled. Other services are available from Kings Cross station via Cambridge, and are also subject to delays and cancellations.

•Keep up to date with the latest weather information online at www.edp24.co.uk

Are you affected by the trains? Contact reporter Annabelle Dickson on 01603 772426 or e-mail annabelle.dickson@archant.co.uk