Official figures show that motorists are 30 times more likely to be killed in the rain than in snow.
But while drivers tend to slow down on snow, they carry on regardless in the rain.
Highways England has launched a “When it rains, it kills” campaign to highlight the 3,000 killed or seriously injured in rain every year.
The campaign includes rain-triggered signs painted on the tarmac outside motorway service stations.
The campaign slogan will flash up when rain falls to hammer home the message.
Highways England figures also show that travelling too fast for the current conditions was identified as a factor in one in 9 road deaths in Britain last year.
The agency said that driving within the speed limit in wet weather could be dangerous if drivers don’t allow extra space between them and the vehicle in front.
Motorists are generally advised to keep a two second gap between them and the car in front in good conditions, four seconds in rain and 10 on snow or ice to allow room to stop in an emergency.
Highways England’s Head of Road Safety, Richard Leonard, said: “Most of us already slow down in snow, ice or fog but when it rains we consider it normal so don’t adapt our driving.
“The sad fact is that 2,918 people were killed or seriously injured on the roads when it was raining last year, and not slowing down to suit the current conditions was identified as a factor in 1 in 9 of all road deaths.
“Rain makes it harder for tyres to grip the road and harder for drivers to see ahead, significantly increasing the chances of being involved in a collision.
“We’ve launched our new campaign to make drivers aware of the dangers and to stay safe.”
The agency said that last year 197 people lost their lives on roads during rainfall in Great Britain and 2,721 suffered a serious injury.
This compares with 14 deaths and 153 serious injuries during fog and 2 deaths and 95 serious injuries during snow.
Highways England advice to drivers in wet weather is:
• Slow down if the rain and spray from vehicles makes it difficult to see and be seen
• Keep well back from the vehicle in front to increase your ability to see ahead and
• Ease off the accelerator and slow down gradually if the steering becomes unresponsive as it probably means that water is stopping the tyres from gripping the road.