Altostratus clouds ucar center for science education. They are formed between 6,500 to 20,000 feet above the ground level. It is lighter in color than nimbostratus and darker than high cirrostratus. Altostratus clouds often form ahead of storms with continuous rain or snow. The types of clouds in the sky include the stratus, cumulus, stratocumulus, altocumulus, altostratus, cirrus, cirrostratus, cirrocumulus, cirrostratus, nimbostratus, and cumulonimbus.
Cirrostratus clouds belong to the high cloud 500000m group. If you see altostratus clouds, a storm with continuous rain or snow might be on its way. Middle clouds, 7 to 2 km 23,000 to 6,500 feet, are altocumulus and altostratus. These clouds always indicate the presence of significant amounts of moisture at middle levels, and, if on the increase, may signal the approach of a frontal system. Occasionally, rain falls from an altostratus cloud. A stratus cloud at an intermediate altitude of 2 or 3 miles. Rare information about altostratus clouds youll want to see. Altostratus clouds are potentially dangerous for aircrafts as it can initiate ice buildup on the aircrafts wings thus altering its aerodynamics.
Mar 01, 2018 the types of clouds in the sky include the stratus, cumulus, stratocumulus, altocumulus, altostratus, cirrus, cirrostratus, cirrocumulus, cirrostratus, nimbostratus, and cumulonimbus. Nimbostratus nimbostratus clouds are dark at the bottom and light near the top. Altostratus cloud is a sign that there is huge amount of moisture in the atmosphere. Altostratus during california winter this is a good example of an altostratus layer. In this video we briefly describe an altostratus cloud and what the dangers are to a pilot, you can always learn more at. Altostratus cloud definition of altostratus cloud by the. They are composed of icecrystals, liquid water droplets. Altostratus clouds develop when the middle layers of the atmosphere are moist and are lifted slowly. Holle altocumulus may appear as parallel bands top photograph or rounded masses bottom photograph. These are usually distinguished by a uniform and plain gray layer with bluish hues. The composition of the clouds is normally stratified. Occasionally, rain will fall from an altostratus cloud. In thinner altostratus clouds, the sun may be dimly visible, commonly referred to as a watery sun. They are similar to cumulus clouds but higher up in.
Altostratus clouds are gray or bluegray in color and tend to appear ahead of rainy weather. The molecular arrangement and other such things has nothing to do with the shape of clouds whatsoever. It may be composed of ice crystals as well as water droplets. Most altostratus decks are middle clouds of uniform or nearly uniform layers formed as a result of lifting. Altostratus clouds are a midlevel cloud layer that look like a bluegray sheet across the sky. Sometimes, the sun or moon will appear to have a halo around it when in the presence of cirrostratus. These are midlevel clouds formed in the troposphere. These clouds are most commonly seen in the winter, and can cause the appearance of a halo around the sun or the moon. These clouds are very tall and may span many of the cloud levels. They are gray or bluegray mid level clouds composed of ice crystals and water droplets. The sun appears as if through ground glass but shadows are not visible on the ground. In the upper troposphere, the terms cirrostratus and cirrus are used. Altostratus clouds are midlevel, gray or bluegray clouds that usually covers the whole sky. Altostratus belong to the middle cloud group 20007000m up.
They are a type of altostratus clouds that form low to the ground, but higher than the nimbostratus clouds. Apr 24, 2019 altostratus clouds cover the sky but are darker than cirrostratus clouds and may give the sun or moon a fuzzy appearance. Since cirrostratus and altostratus form from each other, it is frequently difficult to delineate between the two. Stratiform clouds that both extend through a large fraction of the troposphere and precipitate are called.
Altostratus definition is a fairly uniform midaltitude layer of gray cloud darker than cirrostratus. If the rain hits the ground, then the cloud becomes classified as a nimbostratus cloud. Altocumulus clouds are white or gray in color and composed of water droplets. Clouds are classified into four families according to their height. An altostratus cloud usually covers the whole sky and has a gray or bluegray appearance. Altostratus appears as a uniform sheet either totally or partially covering the sky. Jan 26, 2014 most altostratus decks are middle clouds of uniform or nearly uniform layers formed as a result of lifting. It is a vertical stratus formed in the middle layer and spreads vertically to both the upper and lower layers. The sun or moon may shine through an altostratus cloud, but will appear watery or fuzzy. The cirrus cloud type refers to thin, often wispy, cirrostratus clouds. Without that clue, and the small blue area at top left, this could easily be mistaken for low level stratus. And because they form quite high in the skies, altostratus clouds are quite boring to look at. Though cirrostratus can cover the entire sky and be up to several thousand feet thick, they are relatively transparent, as the sun or the moon can easily be seen through them.
Cloud identification guide international cloud atlas. The 10 basic types of clouds and how to recognize them. The four cloud families are as follows, 1high clouds 2middle clouds 3low clouds 4clouds of vertical development. As with all cumulus clouds, this is a result of a certain amount of instability at cloud level, which gives rise to further uplift at various points within the cloud. These clouds always indicate the presence of significant amounts of moisture at middle levels, and, if on the increase, may signal the approach of a. Altocumulus clouds are composed primarily of water droplets and are located between 6,500 and 20,000 feet 2,000 to 6,000 meters above the ground. The formation of nimbostratus signifies the start of an easy to powerful precipit. With regards to color, altostratus clouds are darker compared to cirrostratus but lighter than nimbostratus. This can result in the change of its aerodynamics, which can lead to dangerous consequences. How does an altostratus cloud form in terms of how molecules. Low level clouds usually have the word stratus in their name. Jan 24, 2016 in this video we briefly describe an altostratus cloud and what the dangers are to a pilot, you can always learn more at.
Atmospheric effects of cirrostratus clouds include halos, sundogs and sunpillars. The sun can shine through, such as in this picture, giving them the name altostratus translucidus. The sun may still shine through these clouds but looks fuzzy or watery. The sun can be seen through thin altostratus, but thicker layers can be quite opaque. Cirrostratus may form by the merging of elements of cirrus, from ice crystals falling from cirrocumulus clouds, from the thinning of altostratus, or by spreading out of the cirrus plumes from the anvil of cumulonimbus clouds. Altostratus clouds types of clouds names of clouds. They are going to be flat long clouds and indicate light continuous precipitation. The base of an altostratus cloud is found within the same levels as the altocumulus cloud. Sometimes it is thin enough to just reveal the sun or moon. However, altostratus clouds themselves do not produce significant precipitation at the. Low clouds, 2 to 0 km 6,500 to 0 feet, are stratocumulus, stratus, and nimbostratus. They are sheetlike thin clouds that usually cover the entire sky.
Altostratus clouds are strato type clouds see below that possess a flat and uniform type texture in the mid levels. These 10 types of clouds are then characterized into the different altitudes in which they typically are found. Altostratus is a middle altitude cloud genus belonging to the stratiform physical category characterized by a generally uniform gray to bluishgreen sheet or layer. The clouds can appear in the shape of puffy masses, flattened layers or parallel bands or waves across the sky. Aug 26, 2016 the molecular arrangement and other such things has nothing to do with the shape of clouds whatsoever. In the thinner areas of the clouds, the sun may be dimly visible as a round disk. The defining feature of altostratus pannus clouds is their expansiveness. Cirrocumulus clouds are thin, sometimes patchy, sheetlike clouds. Altostratus clouds normally have a base between 8,000 and 17,000 feet 2,500 and 5,000 metres. Altostratus definition of altostratus by the free dictionary. They generally appear as a flat, featureless dark grey sheet. A cloud that extends through all three heights is called a cumulonimbus. Description of the different types of clouds sciencing. The four cloud families are as follows, 1high clouds 2middle clouds 3low clouds 4 clouds of vertical development.
Altostratus opacus thick altostratus, the greater part sufficiently opaque to mask the sun or moon completely. They are comprised of ice crystals and water droplets. Cirrostratus clouds indicate upper atmosphere moisture and turbulence, often indicating a change in weather. Altostratus clouds altostratus clouds are gray or bluegray mid level clouds composed of ice crystals and water droplets. Altostratus differs from cirrostratus in that altostratus prevents objects on the ground from casting distinct shadows. Altostratus definition of altostratus by merriamwebster. Altostratus clouds usually form at warm fronts, or places where warm air is blowing across the land and meeting colder air in its path. Altostratus clouds can form ice layers on an aircrafts wings. These sheet like clouds consist of thin widespread ice crystals. Altostratus as this midetage cloud has features similar to stratus, as we have previously discussed. They rarely block out the sun and are fairly uneventful, although may be the precursors of a rain event. Altocumulus from latin altus, high, cumulus, heaped is a middlealtitude cloud genus that belongs mainly to the stratocumuliform physical category characterized by globular masses or rolls in layers or patches, the individual elements being larger and darker than those of cirrocumulus and smaller than those of stratocumulus. Nimbostratus is a cloud that is dark at the base but appears to be illuminate from the centre when observed from below. Note the shadowing on the church tower which indicates a fair amount of sunlight is getting through.
As warm air moves into a region over a cooler air mass, the warm air being less dense rides over the top of cooler air eventually displa. Altostratus clouds are characterized by their uniform gray cloud layer ranging from thin clouds that let you see the sun, to thick layers of clouds that completely block the sun. Stratiform clouds that both extend through a large fraction of the troposphere and precipitate are called nimbostratus. Hooks, feathers, bands or patches with silky shimmer. Vertical clouds usually have the word cumulus in their name. Altostratus is a latin word which can be broken down as alto, meaning middle, stratus, meaning layered. Altostratus clouds are mid level clouds that look like thick veils with a bluish or grayish tint to them. Dictionary entry details altostratus cloud noun sense 1. When an altostratus cloud gets thicker and lower to the. Nimbostratus clouds form from another type of cloud, altostratus clouds. The sun or moon can shine through cirrostratus clouds. Altostratus clouds are dark, middlelevel clouds that take up nearly the whole sky. Transparent milky or fibrous veil, casts shadow, produces halo.
Water droplets can be further classified as ordinary or warm water droplets, and supercooled water droplets. Cirrostratus clouds sheetlike and nearly transparent cirrostratus are sheetlike, highlevel clouds composed of ice crystals. They typically form as a stable air mass is gently lifted, which tends to happen ahead of a front. These clouds form when evaporated water in the air condenses, or cools down and becomes water that groups together. They frequently indicate the approach of a warm front and may thicken and lower into stratus, then nimbostratus resulting in rain or snow.
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