Home
Weather Dublin
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
    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
Low delivers days of gusty conditions. Into the weekend. . . Thursday 17 September 2026
Wind map showing low pressure near the Faroe Islands, with winds reaching 35 mph around Aberdeen and Dublin and stronger Atlantic winds west of the UK.
Thursday 17 September 2026

Into the weekend

Low delivers days of gusty conditions
Severe weather in the Mediterranean. Is a medicane on the way?. . . Monday 14 September 2026
A weather map shows a powerful low-pressure system over the Mediterranean, with warning symbols for storms and heavy rain.
Monday 14 September 2026

Is a medicane on the way?

Severe weather in the Mediterranean
Colourful skies and scenic clouds cover. Your weather - Your shots. . . Sunday 20 September 2026
Split image showing a golden sunset over the sea beneath layered clouds and a pink-purple sunset reflected across calm riverside water.
Sunday 20 September 2026

Your weather - Your shots

Colourful skies and scenic clouds cover
All weather news
This might also interest you
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
Storm Chandra makes impact. Severe gales & heavy rain. . . Tuesday 27 January 2026
Split image showing strong winds over the UK on a forecast map and widespread rain and snow on a weather radar map.
Tuesday 27 January 2026

Severe gales & heavy rain

Storm Chandra makes impact
Long-term trends need a pinch of salt. 40 °C in July?. . . Tuesday 30 June 2026
Temperature radar of 2022 heatwave where the all-time temperature record in the UK was set. Warning symbol overlain.
Tuesday 30 June 2026

40 °C in July?

Long-term trends need a pinch of salt
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

facebooktwitteryouTubelinkList