I see a ring around the moon in the sky. What does this mean?

On Mon, 14 Feb 2000 you wrote:

> TODAY IS FEB 14, 2000, I LIVE ON LONG ISLAND AND THERE IS A HUGH RING AROUND
> THE MOON. I CAN SEE THE WHOLE RING AND THERE ARE PLENTY OF STARS IN THE SKY
> SO PLEASE DONT TELL ME ITS GOING TO RAIN. WHAT DOES THIS MEAN

It is often possible to see a ring around the moon or sun when ice
crystals are present high in the atmosphere. The ring forms because ice
crystals (which are six-sided, just like snowflakes) all refract (bend)
light in the same way. The diameter of the ring is 22 degrees in angle,
although sometimes a second ring can be seen at 44 degrees. This is just
an inherent property of water ice, and has no meaning other than that
there is water present high in the atmosphere.

It does seem to be true that a ring around the moon means bad weather is
on the way. Cirrus clouds, usually made of ice crystals, often arrive a
day or two before a storm system. These clouds can be too thin to be seen
with your eye, especially at night. I see that a small weather system
pushed through New York yesterday and today, so the ice crystals seem to
have been correct!

Thanks for writing!

Sincerely,
Kurtis Williams

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