Above: Stratus Undulatus
Stratus Undulatus
Status clouds are a low level cloud that appears in various forms including status undulatus. Stratus undulatus clouds get their name because the bottom of the stratus cloud appears ruffled and takes on the forms of waves or sand dunes, this is caused by wind shearing across the bottom of the cloud at a medium speed, not enough to break the status cloud up, but enough to disturb it.
What are stratus undulatus clouds?
Stratus undulatus clouds are a low level cloud that typically forms at between 2,000 and 6,500 feet. An approaching warm front will cause stratus undulatus clouds to form. Stratus undulatus clouds can vary in depth and therefore will appear white and more see through in some cases, on the other hand they are able to be quite thick and grey and capable of producing drizzly rain in summer, spring and autumn and light snow in winter in colder climates.
What height are stratus undulatus clouds found?
Stratus undulatus clouds are a low level cloud that typically can form at between 2,000 to 6,500 feet. However in places where fog can form it often rises from ground level thanks to ground warming to form as status undulatus clouds later in the day when the fog has abandoned the ground.
Classification of stratus undulatus clouds
As a low cloud their definition is a C class cloud with the suffix St to recognize that it is a stratus undulatus type.
How are stratus undulatus clouds formed?
Stratus undulatus clouds are formed by the arrival of a warm front that is normally accompanied by falling air pressure and this allows the clouds to form easily. These clouds can also be formed during foggy conditions, as the fog gradually lifts it forms into stratus clouds. Should the clouds be disturbed by light to medium winds the undulatus effect can be observed.
What do stratus undulatus clouds look like?
They are typically seen as slabs of cloud that can actually cover the whole sky; the only distinguishing feature can be the waves as the base of the clouds are ruffled by the wind. Stratus clouds are generally relatively featureless. The stratus undulatus shape is formed as warm air rises and cools at its dew point to form the clouds, should the warmer air be descending the cloud will gradually disperse and eventually should this warming continue the cloud will disappear.
How common are stratus undulatus clouds?
You will be able to find stratus undulatus clouds in the following conditions:
- After fog has formed and the warm air causes the fog to rise but not disperse
- When a warm front is moving in and air pressure falling
- During quiet weather conditions without a dramatic rise of fall of temperature
- In conditions when cumulus convection clouds cannot be formed
Where can I see stratus undulatus clouds?
You will be able to see stratus undulatus clouds anywhere where stratus clouds can form. You will not find these clouds in the Arctic or Antarctic nor will you find them over arid hot locations such as the Sahara desert.