Cloudwatch - chart

High Cloud (cloud base above 6000m)

Cirrus: high-level, wispy cloud. High, white distant looking patches, filaments or long band so ice crystals stretching across the sky. Their shape and texture are often described as looking like mares' tails.

High-level (cloud base above 6000m)

Cirrocumulus: high-level, bubbly cloud. Sheets of organized bands of high clouds having a grainy or tufted appearance

High-level (cloud base above 6000m)

Cirrostratus: high-level, layer cloud. Extensive sheets of transparent whitish cloud either fibrous or smooth textured which sometimes produce halos around the sun.

Medium-level (cloud base 2-600m)

Altocumulus: medium-level, bubbly cloud (3-4,000m). Patterned, white or grayish cloud deck consisting of rounded elements. Frequently in layers, with a roll or honeycomb appearance. Occurs in patches or long bands and sometimes covers the entire sky.

Medium-level (cloud base 2-600m)

Altostratus: medium-level, layer cloud. Grayish or bluish uniform sheet of cloud with very little texture. Usually thicker and grayer and lower in altitude that cirrostratus. Altostratus does not exhibit halos.

Low level (below 2000m) with rain likely

Nimbostratus: layered rain cloud. Dark grey clouds with little visible structure. Usually covers the entire sky and completely hides the sun. Continuous rain is produced in the summer and snow in the winter.

Medium-level (cloud base 2-600m)

Stratocumulus: medium-level, layered, bubbly cloud. Low, distinct, grey or whitish cloud elements with a well defined rounded appearance often merged or organized into rolls or streets. The flat even bases have darker patches.

Low-level (cloud base below 2000m)

Stratus: low-level, layer cloud. Low, uniform, featureless layer of cloud found above a land or water surface. Sometimes produces light drizzle. Known as hill fog when on high ground.

Low-level (cloud base below 2000m)

Cumulus: bubbly cloud. Fair weather clouds with well defined bases, little vertical extent, producing no precipitation and rarely covering more than one-half the sky. They may eventually grow much larger.

Up to 12,000m in vertical extent

Cumulonimbus: towering storm cloud. Large (25 km or more), well organized cloud often exhibiting an anvil shaped top. Produces heavy rain showers, lightning, thunder and sometimes hair or tornadoes. Entire cloud can only be seen from a distance.

Cloud not visible owing to darkness, fog, duststorm, sandstorm, or other phenomena.

Fog: A thin layer of cloud resting on the ground. Normally composed of water droplets but can consist of ice crystals at very cold temperatures. Generally forms in calm or low wind conditions.