Linked from
The 11 pages that link to Visibility, each with the reason it gives.
Dust stormRelated: Dense dust can make roads and runways hazardous by reducing visibility.
FogRelated: Droplets scatter light and shorten the distances at which objects remain visible.
SmogRelated: Smog particles scatter and absorb light, reducing visibility.
MistRelated: Visibility measurements distinguish mist from fog and determine its practical effects.
Stop signRelated: Drivers must see the sign in time to stop safely.