Home
Weather London
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
Career
    Home / Editor's Pick /

    What are solar halos?

15:00
18 June 2023

Weather explained
What are solar halos?

Solar halo
The arc seen in this image submitted from St. Helens is an example of a solar halo. - © Tony Tye

Solar halos are a somewhat common sight, but do you know what they are?

Seen above, this example was sent in by Tony Tye in St. Helens. Halos are a visual phenomenon caused by suspended ice crystals in the air.

The sometimes colourful, often white light circles, arcs and spots in the sky appear via refraction and reflection of sunlight through ice crystals in cirrus clouds in the sky.

As the phenomenon involves light, it is not just tied to the sun but to the moon as well. On bright nights with a full moon, we can see lunar halos appear overhead. You may have heard the myth that a ring around the moon means rain soon.

When a storm approaches, it does not arrive all at once. Both cirrus and cirrostratus clouds act as forerunners in the upper levels of the troposphere.

At night, the moon shines through these clouds and their ice crystals. The more moisture in the atmosphere, the more likely a halo will appear. The more moisture, the greater chance of rainfall.

If you see this phenomenon near you, be sure to take a picture and send it to use via the uploader or tapping the image icon in the app.

Weather & Radar editorial team
More on the topic
Dry, hot weather raises pollen levels. Hay fever comeback. . . Thursday, 18 June 2026
Satellite weather map of the UK and western Europe showing sunny conditions across much of Britain, a rain band approaching Ireland from the Atlantic, and a pollen icon indicating airbourne pollen levels during warm weather.
Thursday, 18 June 2026

Hay fever comeback

Dry, hot weather raises pollen levels
Rain warnings across southern Ireland. Overnight downpour. . . Thursday, 18 June 2026
Satellite weather map of Ireland showing widespread rain bands and extensive precipitation across the west and north, with a heavy rain warning symbol, temperatures around 15 to 16°C, and cloud cover over much of the country.
Thursday, 18 June 2026

Overnight downpour

Rain warnings across southern Ireland
Rising UV levels at the end the week. Mostly to the south. . . Wednesday, 17 June 2026
Split graphic showing a UK temperature map with temperatures reaching 30°C near London on the left and a person applying sunscreen in bright sunshine on the right, with a UV warning symbol highlighting elevated ultraviolet levels.
Wednesday, 17 June 2026

Mostly to the south

Rising UV levels at the end the week
All weather news
This might also interest you
Mixed conditions on an unsettled week. Your weather - Your shots. . . Sunday, 2 November 2025
plit image showing a double rainbow over a rocky shoreline on the left and sheep grazing in a green field under stormy clouds on the right.
Sunday, 2 November 2025

Your weather - Your shots

Mixed conditions on an unsettled week
Historic Storm Éowyn arrives. On this day.... . . Saturday, 24 January 2026
Split image showing a person in a yellow jacket struggling against strong winds and heavy rain on a street at night on the left, and an Irish wind forecast map on the right with red and purple shading, gusts up to 75 mph, and a wind warning icon, divided by a curved white line.
Saturday, 24 January 2026

On this day...

Historic Storm Éowyn arrives
Seasonal warmth between spring thunder. Your weather - Your shots. . . Sunday, 19 April 2026
Split image showing coastal sunset with layered lenticular clouds over rooftops and palm trees on the left, and a green valley with river and hills under soft daylight on the right.
Sunday, 19 April 2026

Your weather - Your shots

Seasonal warmth between spring thunder
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwittertikToklinkList