Why a ring formed around the moon last night near Youngstown, Ohio.

(WKBN) — Pictures and reports of a moon ring were sent to the station last night. These fun weather optics are caught from time to time through the year.

Maybe you caught this ring/halo too as you were looking up in the sky to catch a glimpse of the Green Comet.

Moon ring is shown through the trees in the Leetonia area
Courtesy: Jarrid Stark

How a moon halo or ring is created

A moon halo, also known as a lunar halo or ring, is a circle around the moon. It happens when the moon’s angle to high-level clouds directs moonlight to the ice crystals of the clouds. High clouds are made of tiny ice crystals.

The light is refracted from the ice crystals and creates a prism, causing a rainbow color from each. This also happens with the sun.

Refraction – Moonlight hits Ice crystals and the light is dispersed into a spectrum of visible colors.

The angle of the moon and the person seeing the halo has to be at a certain threshold.

This dispersion of light with the ice crystals creates a ring around the sun called a moon halo.

A halo is produced around the sun and the moon from high ice crystals in the sky.
The halo is produced from the viewer’s location at 22° and 46° above the horizon.

Does a moon halo forecast the weather?

The answer to the question if a sun halo can predict the weather is both yes and no.

The halo is produced from ice crystals of high cirrus clouds. High cirrus clouds can be a sign that a warm front is moving toward a region. These high cirrus clouds will slowly build their way up high in the atmosphere as warmer air is forced upward over the top of colder air.

The cirrus clouds are typically the first type of clouds to form as a warm front moving toward an area.

A warm front will help create thin clouds as it approaches the area.
A warm front moving into a location: Clouds get thicker the closer you get to the warm front.

Why the moon halo can forecast the weather

The moon halo is formed from ice crystals in cirrus clouds. The cirrus clouds could be a sign that a warm front is approaching the area. If that is the case, you could expect warmer temperatures to move in as well as thicker clouds as the warm front approaches. As the clouds get thicker, you may experience precipitation.

So, yes: The moon hello, or sun hello, can be a good indicator that a warm front is approaching and that precipitation may follow soon.

Why the moon halo does not forecast the weather

The ice crystals in the sky may not always be from the process of a warm front developing. They could be left over from big towering thunderstorms a long distance from your location. They may also be there as a warm front approach, but it slides south of your region. The weather does not change as the front does not move through.

In the end, the moon halo is a great thing to catch and makes for fantastic pictures, but it’s not a great weather forecaster all of the time. It may be hard to tell what is causing the high-level ice crystals resulting in a forecast that does not have a solid base.

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