Halos are faint white rings that show up in the sky both around the sun and moon.
According to weather lore, halos have been thought to signal wet weather on the way as indicated in the phrase "a ring around the sun or moon means rain or snow is coming soon.”
Cirrus clouds are high, wispy clouds mostly made of ice crystals versus the larger water droplets found in most clouds.
The halo effect happens when ice crystals refract and reflect the light as cirrus clouds spread thinly across the moon or sun. Most commonly, the light is bent in a way it creates a 22-degree angle or a 22-degree halo.
This is not to be confused with a corona, another type of circular shape that also occurs around the moon and sun. They aren't as big as halos and consist of small water droplets, which give out a different effect and color, almost like a rainbow.
Coronas can indicate an increase in moisture.
Weather systems usually move from west to east in mid-latitudes.
If the cirrus clouds are coming from a system that's to our south or north, that means the unsettled weather could miss us as it moves eastward. If the system and associated clouds are more to our west, there's a better chance it could come our way.
Most halos are not associated with frontal systems, so you can't always rely on just the halos for weather prediction.
