Motorists have been warned to avoid flooded roads as a deluge hit parts of northern England causing train services to be cancelled.
Hours of torrential rain in Sheffield and other parts of South and West Yorkshire have left streets like rivers and some routes impassable.
Train services have been affected by flooding across the Pennines and South Yorkshire and tram-train services between Rotherham and Sheffield have also been hit by the weather.
The Met Office has issued an amber warning for heavy rain until 6am on Friday for an area between Sheffield, Manchester and Bradford.
It has also issued yellow warnings for surrounding regions as it said 40mm of rain had fallen in the Sheffield area between midnight and noon on Thursday.
Forecaster Craig Snell said it could be that the total hits 100mm by Friday morning.
He said driving conditions would continue to be challenging in West and South Yorkshire as well as across the Pennines and Manchester into Friday.
The rail firm Northern said that a number of routes, including the Todmorden-Rochdale cross-Pennine line, had been closed due to flooding and said on Twitter: "Due to heavy rain flooding the railway at #RotherhamCentral all lines are blocked".
South Yorkshire Police issued alerts including one which said: "Please adjust your driving to suit the extreme conditions during the next 24 hours. We have more rain forecast and many roads have standing water which varies in depth, so please drive with caution and reduce speed to allow time to react."
Another said: "Please try and avoid Rivelin Valley Road. Between Malin Bridge and Rails Road there are several large floods which are very deep in areas."
Sheffield City Council's Streets Ahead team said on Twitter: "Our teams are busy responding to reports of flooding & wet spots across the city. Remember to take extra care when travelling and drive according to the weather conditions."
Social media users posted images of flooding across Sheffield, including along Penistone Road, and rising levels along various sections of the River Don.
The Environment Agency has issued 25 flood warnings, mainly in the Yorkshire region, and 84 flood alerts.
Chris Wilding, flood duty manager at the Environment Agency, said: "Heavy rain could lead to surface water and river flooding across parts of northern England today and into tomorrow, particularly in parts of Yorkshire, Greater Manchester, Derbyshire and Lincolnshire.
"Persistent showers may also bring localised river and surface water flooding to parts of southern England today and tomorrow.
"Our incident rooms are open and we are working closely with local authorities and partners to reduce the risk of flooding.
"Our field teams are ready to deploy temporary flood barriers to help protect people and property if needed.
"We advise people to stay away from swollen rivers and not to drive through flood water as just 30cm of flowing water is enough to move your car."
Amber weather warnings are defined as an increased likelihood of bad weather affecting you, which could potentially disrupt your plans and possibly cause travel delays, road and rail closures, interruption to power and the potential risk to life and property. Amber means you need to be prepared to change your plans and protect you, your family and community from the impacts of the severe weather based on the forecast from the Met Office.