Dyfed Powys Police are urging drivers to take their advice as the autumn nights draw in and weather conditions change.
With the nights getting darker and the weather set to become unpredictable, drivers are being urged to make sure their car is ready for such conditions.
During the autumn and winter, motorists and cyclists have to deal with flooding, frost, sleet, snow, icy winds, icy roads and fog.
Dyfed Powys Police road safety officer, Sue Storch, said: "The best advice in severe weather is to stay off the road.
"Poor driving can lead to accidents, particularly when accompanied by inclement weather.
"Motorists need to ensure their vehicle is ready for the winter months, has been regularly serviced and deemed safe to drive by experts."
Advice includes: Before you start your trip - allow extra time to clear the windows properly; ensure your vehicle is prepared for the journey; make sure your lights work; check all your tyre pressures are correct; make sure you have sufficient windscreen washer fluid; ensure you have sufficient amount of petrol for your trip; carry warm clothing, blankets, a torch, a shovel, a bottle of water and suitable footwear.
In bad weather - reduce your speed; increase stopping distances.
In fog - drive very slowly using dipped headlights; use fog-lights if visibility is seriously reduced, but remember to switch them off when visibility improves.
Flooded roads - don't attempt to cross if the water seems too deep; stay in first gear, but keep the engine speed high by slipping the clutch - this will stop you from stalling; drive slowly and avoid areas where the water is deepest, usually near the kerb; remember - test your brakes when you have passed the flooded area before you drive at normal speed.
On icy roads - if you do hit ice and feel the car start to slide, take your foot off the accelerator immediately, don't be tempted to brake (this will increase your risk of spinning) and steer gently into the slide. The best way to avoid sliding in the first place is to make sure your speed is right; it may need to be slower than you think - at just 30 mph, you are travelling 30 feet every second.