Rail services through Newark Northgate cancelled as temperatures expected to reach 40C
Rail passengers are being asked to avoid travelling on Monday (July 18) if possible and not to travel by train at all the following day because of high temperatures.
Rail services through Grantham will be affected by delays and cancellations on Monday and Tuesday (July 18 and 19).
LNER says no trains will operate to London from Newark on Tuesday.
Temperatures are expected to rise to 40C, with a red weather warning in place, on Tuesday and National Rail says this could affect the rails and overhead power lines.
In a statement on the LNER website, it says: "Only travel if absolutely necessary on Monday 18 July, and on Tuesday 19 July, do not travel on routes south of York and south of Leeds to London King’s Cross as no trains will run, this includes to or from Wakefield Westgate, Doncaster, Retford, Lincoln, Newark Northgate, Grantham, Peterborough and Stevenage.
"There will be limited trains to other destinations and it's highly likely that they will be subject to significant delays because speed restrictions will be in place.
"If you do have to travel please check your journey before you set off."
East Midlands Railway also says its services will be reduced.
National Rail also asked passengers not to travel unless absolutely necessary over the next few days.
A spokesman said: "Hot weather can affect the rails, overhead power lines and the ground which the track sits on. As a result, Network Rail may impose temporary speed restrictions to reduce the risk of damage to the railway and keep services running.
"Please check before you travel and allow more time for your journey on the affected days, as speed restrictions can cause train delays and cancellations."