Home / Editor's Pick /

Weather explained: What are noctilucent clouds?

15:00
28 August 2022

Weather explained
What are noctilucent clouds?

Noctilucent cloudsNoctilucent clouds shine in the night sky over Tynemouth Priory and Castle in June 2022. - © picture alliance

Bright, shimmering noctilucent clouds illuminate the skies each year with a season spanning from May to August, here's how.

Known as noctilucent clouds, these rare clouds form around 50 miles above Earth’s surface in the mesosphere during summer months.

The unusual display of blue and silver ribbon clouds can keep the evening sky bright hours after the sun has set.

It is not known for sure how these clouds form, although we know that they shine thanks to the sun’s light illuminating ice crystals from beyond the horizon.

These crystals reflect the light onto dust particles in the mesosphere, where temperatures reach -134C.

Best viewed when the sun has just set below the horizon, 90 minutes after sunset, the clouds are most likely to appear between June and August for those of us in the Northern Hemisphere although their full season runs from May to August.

If you spot any bright shining clouds at night in the coming months, we would love to see them!

Snap a picture and submit by tapping the image icon in our app or use the dedicated picture uploader.

Weather & Radar editorial team
More on the topic
Map of Europe showing low pressure over Russia and a strong cold air flow towards Eastern Europe. Significant drop in temperatures across large parts of the east.
Thursday, 11 December 2025

Frost and snowfall

Cold air intrusion in Eastern Europe
Weather radar showing clouds and showers over Algeria and Morocco. Next to it, a warning map with the rain area in Algeria marked. Surrounding regions mostly sunny and dry.
Thursday, 18 December 2025

Algeria affected

Rain in the desert
Radar map showing widespread blue rain bands over the UK and Ireland with a triangular heavy-rain warning icon placed over central Britain.
Tuesday, 16 December 2025

Thursday rain

Incoming downpour prompts warnings
All weather news
This might also interest you
Split weather map showing the UK and Ireland. The left side illustrates strong winds circulating around a low-pressure system, with gusts of 20–30 mph highlighted in orange and yellow. The right side shows radar imagery with widespread blue rain bands and patches of thunderstorms, especially over northern England and Scotland.
Thursday, 28 August 2025

Breakfast brief

Remaining widely unsettled
Sunday, 24 August 2025

Your weather - Your shots

Mammatus clouds widely spotted
Weather graphic showing rain and wind fields over the Canary Islands and a central warning symbol.
Friday, 12 December 2025

Storm and rain

Turbulent weather in the Canary Islands
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