Nimbostratus cloud
- Cirrus Ci
- Cirrocumulus Cc
- Cs cirrostratus
- Altocumulus Ac
- Alto Stratus Ace
- Stratocumulus Sc
- Stratus St
- Cu Cumulus
- Cumulonimbus Cb
- Calvus cal
- Capillatus cap
- Castellanus cas
- Congestus con
- Fibratus fib
- Floccus flo
- Fractus fra
- Humilis hum
- Lenticularis len
- Mediocris med
- Nebulosus neb
- Spissatus spi
- Stratiformis st
- Uncinus unc
- Duplicatus you
- Intortus in
- Lacunosus la
- Opacus op
- Perlucidus pe
- Radiatus ra
- Translucidus tr
- Undulatus un
- Vertebratus ve
Special shapes
- Arcus ar
- Incus in
- Mom ma
- Pannus pa
- Pileus pi
- Tuba tu
- Velum ve
Nimbostratus, Ns (Latin nimbus " rain cloud " and stratus or sternere " extend, spread, cover with a layer ") is a more or less featureless, blue-gray cloud cover, which usually begins from mid-levels and often causes long-lasting rainfall.
Design and appearance
Nimbostratus consists of (sometimes supercooled ) water droplets and raindrops, ice or snow crystals, or a mixture of said liquid and solid particles. They are caused by Aufgleitbewegung to a warm front.
This type of cloud occurs usually as a broad, deep-set, dark gray layer of highly diffuse bottom falls out of the prolonged precipitation in the form of rain, snow, ice pellets or freezing sleet that does not necessarily reaches the ground. In the tropics may vary, particularly during short rain breaks are observed, such as nimbostratus is divided into several different cloud layers, which grow together quickly.
The underside of nimbostratus is often of lower-lying, ragged clouds ( pannus ) partially or completely obscured, which form at or below the nimbostratus ceiling and change its shape quickly. First, this pannus clouds consist of isolated single cloud; later they may merge to form a continuous layer. If the pannus clouds cover large parts of the sky, so special care should be taken that they are not confused with the underside of a nimbostratus cloud. Nimbostratus has neither specific nor species subspecies. For special shapes, accompanying and mother clouds see Article cloud.
The horizontal extent of the nimbostratus accordingly often reaches the warm front course several hundred miles wide. By Aufgleitbewegung the warm front of nimbostratus is a very large area in the direction of pull, resulting in long hours, lasting precipitation ( " Country Rain" ), which frequently extends over the whole day. Also the vertical nimbostratus is one of the extensive cloud genera: His ceiling is located in temperate latitudes to heights between 5 and 10 kilometers, which can hardly penetrate sunlight on the earth. Thus, the nimbostratus has the status of "classic bad weather cloud".
Demarcation from other cloud types
The nimbostratus, in contrast to Alto Stratus to a darker gray color and covers the sun totally. From the altostratus almost no precipitation and from the Stratus only drizzle falls. The bottom of the nimbostratus is unclear and may show darker contours.