Home / Editor's Pick /

What's that cloud: The wispy altocumulus floccus

15:00
19 February 2023

What's that cloud?
The wispy altocumulus floccus

Altocumulus floccus cloudsAn example of altocumulus floccus clouds seen in St Albans, Hertfordshire last year. - © Alan Steele

These fibrous looking clouds were sent in by a user this week, do you have any idea what they are?

Known as altocumulus floccus clouds, this particular cloud type is known for its patchy, wool-like appearance. Capable of forming anywhere from 2,000 m to 6,000 m they regularly arrive in clusters.

Their arrival typically indicates some instability but at times of a deeper, unstable layer can swell to form thunderstorms.

Regular altocumulus clouds are more associated with settled conditions but come in many forms. In addition to floccus we also see altocumulus stratiformis, lenticularis, and castellanus.

Altocumulus floccus often pair with the castellanus variety whose name derives from their resemblance to castle turrets.

Have you seen any interesting or unusual clouds recently? Send them in and we'll explore how and why they form! Use our uploader or tap the camera in the app to submit photos.

Ryan Hathaway
More on the topic
Split image showing a snowy Christmas market on the left and a UK weather map on the right with pink zones indicating widespread snowfall over Liverpool, Manchester, Birmingham, and Newcastle, plus white snow icons.
Monday, 8 December 2025

Everyone wants to know...

How likely is a White Christmas?
Split image showing a low-tide estuary at sunset on the left with concrete blocks, boats, and pastel sky, and a bright full moon on the right glowing through thin clouds above dark tree silhouettes, divided by a curved white line.
Sunday, 7 December 2025

Your weather - Your shots

Winter weather snaps and a supermoon too
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
All weather news
This might also interest you
Split weather map showing UK wind speeds in orange-red shades up to 40 mph on the left and warning levels in green-yellow on the right, with a central wind warning sign.
Wednesday, 22 October 2025

Warnings active

Storm Benjamin impacts the UK
Wednesday, 27 August 2025

Breakfast brief

Frontal system brings heavy rain
Weather map of the UK and Ireland showing scattered showers with cloudy patches across much of the region, especially around western and northern areas. Sunshine symbols appear over London, Cardiff, and parts of southern England, while temperatures range from 17°C to 18°C in most places. Areas of heavier rain are visible over the Atlantic to the west.
Friday, 29 August 2025

Breakfast brief

Unsettled conditions into the weekend
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