Cloud Appreciation Day 2025 is here

For us astronomers—clouds can suck (on Earth anyway). But cloud Appreciation Day is an annual initiative by the Cloud Appreciation Society that invites people worldwide to stop, look up, and celebrate the clouds above them. The event encourages participants to photograph their local skies, write reflections, and submit their contributions to the Memory Cloud Atlas, an ever-growing digital archive of cloud images and personal impressions. While stargazers often mutter about cloudy nights obscuring their favorite galaxies, this project offers a chance to appreciate clouds as fascinating atmospheric features, not just astronomical annoyances.

Collecting and organizing clouds - it's good to have Cloudy Nights (sometimes!)

The Memory Cloud Atlas is a permanent, online photo archive designed to capture snapshots of the world’s skies from every corner of the globe. Participants upload their images and brief personal reflections via the Cloud Appreciation Society website or through its mobile app, CloudSpotter. Submissions are then organized by date, location, and cloud classification, creating a rich visual dataset of atmospheric conditions.

Teachers and students can use a dedicated “Cloud Appreciation Pack,” which includes lessons and activities about cloud types, weather systems, and atmospheric science. Over time, this community-built database is becoming an accessible historical record of the planet’s cloud cover, freely browsable for anyone who wants to see what the sky looked like on a specific day—even if it blocked an astronomer’s prized planetary conjunction.

Notable cloud contributions

For Cloud Appreciation Day 2025, submissions included cirrus fibratus over Sydney, altocumulus lit by sunrise in Kent, England, cirrus intortus twisting above Lompoc, California, and altocumulus lenticularis floating like UFOs over Helena Valley, Montana. Each image was paired with a short reflection, such as a memory of a morning walk, a moment of calm, or a quick phone snap before rushing to work.

The collection paints a vivid, global picture of atmospheric diversity. For astronomers, this is also a visual record of “those nights when Saturn was behind three layers of stratus,” while planetary scientists might delight in comparing these Earth-based formations with images of Martian dust storms or Venusian cloud decks.

Applications across disciplines

• Astronomy and astrophotography (and cloudy nights): Cloud Appreciation Day may feel like a cruel joke to telescope owners who plan observing sessions only to be greeted with overcast skies. However, the archive has genuine value: a growing visual log of sky conditions can inform planning for future observations or help amateur astronomers recall weather patterns during key celestial events. It even highlights cultural humor within astronomy circles, where clouds are both a nuisance and a reminder of the planet’s dynamic atmosphere.
• Education and citizen science: The event has become a simple way to get students excited about meteorology, atmospheric optics, and science communication. The Memory Cloud Atlas is an example of citizen science in action, where participants of all ages contribute useful environmental data without specialized training.
• Climate and environmental research: Researchers studying climate change and weather trends may eventually use this visual dataset to track patterns of cloud cover, haze, or pollution levels across decades. The public involvement makes the data more geographically diverse than many traditional observation networks.
• Art and cultural engagement: The Cloud Appreciation Society promotes clouds as more than weather phenomena. Submissions often carry artistic or poetic qualities, making the Atlas both a scientific and cultural resource. Astronomers, despite their frustrations, might find inspiration in seeing familiar weather patterns in a new light.

Real-world implications for Cloud Appreciation Day 2025

Cloud Appreciation Day’s lighthearted approach to atmospheric observation has serious benefits. By crowdsourcing photos from around the world, the initiative encourages people to pay attention to the sky and fosters awareness of environmental changes. Over time, this citizen-led record may complement satellite imagery by adding human perspectives to atmospheric monitoring.

For astronomers, clouds remain a persistent obstacle to observations, but this annual event reframes those “bad seeing” nights as part of a shared global experience. The humor of the event’s popularity lies in its reversal of traditional astronomical priorities: rather than lamenting cloud cover, participants celebrate it, demonstrating that scientific curiosity can thrive in both clear and cloudy skies.

Cloud Appreciation Day for everyone but astronomers and astrophotographers

This day reflects the playful tension between two sky-gazing communities: weather and cloud enthusiasts who eagerly document the shifting skies, and astronomers who spend countless hours hoping for perfectly transparent nights. Cloud Appreciation Day reminds us that even atmospheric interference can be fascinating when viewed as part of the planet’s dynamic system. While telescopes may prefer Mars’ thin atmosphere or the wispy clouds of Venus captured by probes, this Earth-based archive offers an accessible, community-driven view of our ever-changing sky.

The Full Moon And Clouds, by Richard Harris, Astronomer in Strafford, Mo

Shot with a Canon 6D Full frame camera, ISO 1000, 1/13 shutter, 85mm Canon EOS lens