California has a "Basic Speed Law." This law means that you may never drive faster than is safe for current conditions. For example, if you are driving 45 mph in a 55 mph speed zone during a dense fog, you could be cited for driving "too fast for conditions." You may never legally drive faster than the posted speed limit, even if you think it is safe.
Regardless of the posted speed limit, your speed should depend on:
- The number and speed of other vehicles on the road.
- Whether the road surface is smooth, rough, graveled, wet, dry, wide, or
- Bicyclists or pedestrians walking on the road’s edge or crossing the
- Whether it is raining, foggy, snowing, windy, or dusty.
Maximum Speed Limit
The maximum speed limit on most California highways is 65 mph. You may drive 70 mph where posted. Unless otherwise posted, the maximum speed limit is 55 mph on two-lane undivided highways and for vehicles towing trailers. Other speed limit signs are posted for the type of roads and traffic in each area. All speed limits are based on ideal driving conditions. Construction zones usually have reduced speed zones.
Driving faster than the posted speed limit, or driving faster than safe for current conditions on any road is dangerous and illegal. High speed increases your stopping distance. The faster you go, the less time you have to avoid a hazard or collision. The force of a 60 mph crash is not just twice as great as a 30 mph crash, it’s four times as great!