MOTORISTS are being warned this bank holiday weekend could spell one long headache.

Travel organisations are predicting Dorset roads will be gridlocked with thousands heading to the coast to enjoy the last days of August.

They say major engineering works on main line train services over the next few days are partly to blame as holidaymakers will opt to go by car or coach instead.

Alison Birkett, the AA's spokesman for Dorset, said: "It is guaranteed to be a lot busier than a normal bank holiday. Roads will take the brunt of traffic as people who had planned to go by train to places like Dorset may decided to go by car or coach."

She said hot spots will be the A354 from Dorchester to Weymouth and the A35 from Lyme Regis to Weymouth.

The AA urges drivers to be prepared for traffic jams by carrying water with them to combat dehydration and to check tyres, oil and lights before setting off.

Keith Salmon, chairman of the World Heritage Coast Hospitality Association, is calling for a long-term overhaul of the road system to cope with tourist traffic.

He said: "I am afraid Weymouth will be gridlocked. We need to have a whole new look at our road system in Weymouth and Portland.

"I feel for people coming down to Weymouth and we need to be aware it takes at least 24 hours for them to wind down after a bad journey."

He added that tourists who get stuck in traffic en route to their holiday destination may change their mind and go elsewhere.

South West Trains (SWT) is stepping up its service on the Waterloo to Reading line because the track between Slough and Reading will be shut for engineering works.

Cathryn Rowe for South West Trains, said: "We are strengthening our service to Reading to cope with extra demand. But we are not expecting this to affect services in and out of Dorset."