The Ring Around the Moon Phenomenon

If you were up early yesterday (Wednesday February 3rd) you may have seen a large ring around the moon. It’s a pretty cool sight to see in person if you ever get the chance sometime.

The ring develops due to refracted and reflected moonlight off of ice crystals in the atmosphere. These ice crystals are usually located high up in the clouds, typically within cirrus clouds that move into the area.

The light refracts at angles no smaller than 22 degrees and sometimes leads to a 22 degree halo around the moon which is 44 times larger than the moon itself. Different colors of light are bent at different angles and that could cause a red or blue tint to the ring. This same phenomenon can happen around the sun as well.

Old weather folklore says that if you spot a ring around the moon or what some call a “Lunar Halo,” then bad weather is in the near future, usually within 24-48 hours. A warm front typically brings cirrus clouds which causes the light refraction, and a cold front is usually right behind the warm front. The cold front is what typically brings the changing weather that can sometimes be bad. This Lunar Halo over Delmarva has proved the old folklore correct because big changes are in the forecast today in the form of a strong arctic cold front.

Here’s what the ring looked like in Salisbury yesterday.

A similar ring was also spotted in England earlier in the week and taken with a higher quality camera. It was taken by ISO Images LTD. See below:

This is a graphic to give some detail on how the halo forms.