nimbostratus cloud

Nimbostratus cloud: Thick dark stratus, giving rain which is often heavy and prolonged.

The next set of clouds are the rain-bearing nimbostratus clouds.

Fractonimbus may eventually merge completely with overlying nimbostratus clouds.

Stratiform precipitation falls out of nimbostratus clouds.

Nimbostratus virga is a form of Nimbostratus cloud in which the precipitation never reaches the ground.

A nimbostratus cloud is characterized by a formless cloud layer that is almost uniformly dark grey.

Altostratus and nimbostratus clouds always have this physical appearance without significant variation or deviation and, therefore, do not need to be subdivided into species.

The base of a nimbostratus Cloud base cloud is dimmed by precipitation and is usually not clearly visible.

It retains the same features as a normal nimbostratus cloud; dark in appearance, low to medium level cloud of moderate vertical development and made up of sheets.

A nimbostratus virga cloud is the same as a normal nimbostratus cloud, but the precipitation is virga and it never reaches the ground.

The prefix nimbo- or the suffix -nimbus indicates a precipitating cloud; for example, a nimbostratus cloud is a precipitating stratus cloud, and a cumulonimbus cloud is a precipitating cumulus cloud.

The band of precipitation that is associated with their warm front is often extensive, forced by weak upward vertical motion of air over the frontal boundary, which condenses as it cools off and produces precipitation within an elongated band, which is wide and stratiform, meaning falling out of nimbostratus clouds.