By: Meteorologist Courtney Steimann
Updated: Feb 26th 2019

Courtney's Cloud Corner: Crepuscular Rays

Following the previous post “Courtney’s Cloud Corner: Clouds on Fire”, we will discuss Crepuscular rays.

Crepuscular rays have been commonly known as sunbeams or sun rays. They are associated with sunrises and sunsets.  It occurs when the sun light passes through the gaps of clouds and forms a ray of sunlight for us to admire.  It is not only clouds that help this phenomena, it is because of the light  from the sun being scattering when it passes through small water droplets that are within the clouds, aerosols, air molecules, or airborne dust that cause it to be seen streaming down to earth.  Although the sun may beam down parallel to the cloud, usual the rays that we see are diverging outwards.  This is because of the distance and perspective.  For example, imagine your gazing down a long straight road. The road appears to be narrowing or converging with the longer distance.  This is a similar instance of what happens when light diverges as it passes the clouds or obstruction. Nevertheless, crepuscular rays will be a beautiful sight to see.


Crepuscular Rays in the desert
Crepuscular Rays
A narrowing long road.
An example of converging or narrowing road.