How do I make a script change the color and fog end of fog?

The particle parts works btw.
Im trying to make an occasional sand storm happen.

script.Parent.Dust.Enabled = false
game.Lighting.FogEnd = 3000
game.Lighting.FogColor = Color3.new(201, 138, 130)
wait(5)
script.Parent.Dust.Enabled = true
game.Lighting.FogEnd = 300
game.Lighting.FogColor = Color3.new(167, 175, 146)
return