Altocumulus undulatus | |
Family | B |
Type | Altocumulus |
Occurrence | Worldwide |
Altitude | 2000-5000m |
Formation | Lifting of a large air mass followed by condensation combined with atmospheric instability and wind shear at cloud level |
Precipitation | Light rain if cloud is thick |
Potential Hazards | May signal approaching frontal system |
Altocumulus Undulatus are patches or layers of small grains arranged in bands. They have a wavy appearance due to wind shear and usually cover only a small portion of the sky. Occasionally they form two or more overlapping waveforms. The presence of Altocumulus undulatus may indicate precipitation within the next 20 hours or simply a cloudy day.
Clouds | |
---|---|
High Clouds (Family A): | Cirrus (Ci) • Cirrus aviaticus • Cirrus intortus • Cirrus radiatus • Cirrus uncinus • Cirrus Kelvin-Helmholtz • Cirrostratus (Cs) • Cirrocumulus (Cc) • Pileus • Contrail |
Middle Clouds (Family B): | Altostratus (As) • Altostratus undulatus • Altocumulus (Ac) • Altocumulus undulatus • Altocumulus mackerel sky • Altocumulus castellanus • Altocumulus lenticularis |
Low Clouds (Family C): | Stratus (St) • Orographic stratus • Fog • Nimbostratus (Ns) • Cumulus humilis (Cu) • Cumulus mediocris (Cu) • Stratocumulus (Sc) |
Vertical Clouds (Family D): | Cumulonimbus (Cb) • Cumulonimbus incus • Cumulonimbus calvus • Cumulonimbus with mammatus • Cumulus congestus • Cumulus castellanus • Pyrocumulus • Pyrocumulonimbus |