Cloud Atlas
Cumulus (Cu)
Classic ‘cotton ball’ clouds with crisp edges — the default cloud you draw as a kid.
How to spot it
- Detached puffs with brighter tops and flatter, darker bases
- Often grows through the day over land (diurnal convection)
- Sharp outlines; shadows and contrast are common
What it can mean
- Small, scattered cumulus usually indicates fair weather
- If they grow taller (towering cumulus), showers or storms become more likely
- A good visual indicator of active rising air
Photography tips
- Expose for highlights to keep texture in the tops
- Wide-angle can emphasize depth + scale
- A polarizer can help (but watch for uneven sky darkening)