What is Visibility?
[[File:Sunrise in the fog 7723.jpg|thumb|200px|Visibility can be poor on foggy days.]] ''Visibility'' is a word used in [[meteorology]]. It is used to talk about how far a normal person can see depending on the [[weather]]. If there is low visibility, such as in a [[blizzard]], a person will not be able to see far. If there is high visibility, such as on a bright, sunny day, a person will be able to see a long way. Visibility less than {{convert|100|m|ft}} is often called zero. When it is this low, [[road]]s may be closed, or lights and signs are turned on to warn drivers. These are put in areas that often have very low visibility. Warning lights help stop [[automobile accident|accident]]s. [[Automobile]] crashes with many cars happen often in places like this if the warning lights and signs are not put up. Visibility is said to be good when a person can see farther than about 10 [[kilometer]]s.<ref>Gifford, Clive; Lisa Clayden (2002). Family flip quiz: Geography. Great Bardfield, Essex, CM7 4SL: Miles Kelly. {{ISBN|1-84236-146-5}}.</ref> An [[advisory]] is put out by meteorologists to warn of low visibility, such as a [[dense fog advisory]] from the [[U.S.]] [[National Weather Service]]. These tell drivers to not [[travel]] until the [[fog]] leaves. [[Airport]] travel sometimes is delayed, or slowed down, by low visibility. == References == {{reflist}} [[Category:Weather]]