Police said that at 4.50pm today, Monday, November 21, persistent rain was causing problems on the A61 Wakefield to Barnsley road.
One driver said the water was about a foot deep near to Newmillerdam and was up to the bottom of her car door.
The road remains open for now but motorists are being urged to be cautious.
Meanwhile, a tree has fallen on onto the road at Cliffe Lane, Cleckheaton, blocking one side of the carriageway.
The Met Office has issued a “yellow warning” of rain from noon today until 6am on Tuesday, accompanied by strong northeasterly winds giving gusts of 40-50 mph.
Wet weather is expected to sweep across the south west and move north in the wake of Storm Angus, causing damage and disruption as it falls on already saturated ground.
The Environment Agency said it is preparing to put up temporary defences “where necessary” and said rivers have been cleared to make sure water can flow freely.