Rain, Fog, Using Windshield Wipers

• When it is raining, foggy or smoky outside or dust is blowing, turn on your headlights.
  
  If you have to use your windshield wipers a good rule of thumb is to turn on your headlights at the same time, suggests CarInsurance.com.
  
  

Sunset

• Depending on the state that you live in, you may be required to turn your headlights on at sunset, which is typically about an hour before full darkness sets in. Some states mandate that drivers turn their headlights on before the onset of sunset.
  
  

Specific State Laws

• In California, a driver is required to dim his lights whenever he is within 500 feet of oncoming traffic or within 300 feet of a vehicle that is in front of him. Other states might specify slightly different distances for dimming.
  
  

Icy Weather

• Use your headlights on cold, icy mornings when the windows of other drivers may be fogged up.
  
  

Get Someone's Attention

• Turn on your lights to get the attention of another driver.
  
  

Treacherous Roadways

• When driving on mountainous or country roads turn on your headlights so that other drivers can see you approaching.