Cirrus uncinus cloud
Encyclopedia
Cirrus uncinus is a type of cirrus cloud
. The name cirrus uncinus is derived from Latin
, meaning "curly hooks". Also known as mares' tails, these cloud
s are generally sparse in the sky
, and very thin.
The clouds occur at very high altitude
s, at a temperature of about minus 40-50 Celsius. They are generally seen when a warm
or occluded front
is approaching. They are very high in the troposphere
and generally mean that precipitation
, usually rain
, is approaching.
Cirrus cloud
Cirrus clouds are atmospheric clouds generally characterized by thin, wispy strands, giving them their name from the Latin word cirrus meaning a ringlet or curling lock of hair...
. The name cirrus uncinus is derived from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
, meaning "curly hooks". Also known as mares' tails, these cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...
s are generally sparse in the sky
Sky
The sky is the part of the atmosphere or outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons. During daylight, the sky of Earth has the appearance of a pale blue surface because the air scatters the sunlight. The sky is sometimes...
, and very thin.
The clouds occur at very high altitude
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
s, at a temperature of about minus 40-50 Celsius. They are generally seen when a warm
Warm front
A warm front is a density discontinuity located at the leading edge of a homogeneous warm air mass, and is typically located on the equator-facing edge of an isotherm gradient...
or occluded front
Occluded front
An occluded front is formed during the process of cyclogenesis when a cold front overtakes a warm front. When this occurs, the warm air is separated from the cyclone center at the Earth's surface...
is approaching. They are very high in the troposphere
Troposphere
The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 80% of the atmosphere's mass and 99% of its water vapor and aerosols....
and generally mean that precipitation
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
, usually rain
Rain
Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...
, is approaching.