Middle Clouds - Altocumulus (Ac)
Middle clouds are composed of water and/or ice
Cloud-base heights for middle clouds:
| Tropical Region | Middle Latitudes | Polar Regions |
| 2-8 km | 2-7 km | 2-4 km |
- Altocumulus Clouds - shallow, puffy or wave-like in appearance
- appear the size of your thumbnail when holding your arm up to the sky
