A altocumulus cloud
cloud to cloud lightning
nimbostratus cloud
A cirrostratus cloud is a high, thin, generally uniform stratiform type composed of ice-crystals. It is difficult to detect and is capable of forming halos when the cloud takes the form of thin cirrostratus nebulosus.
The cloud you are asking about is called the Cirrus cloud. It nearly always is the highest cloud in the sky and is very white and thin to the naked eye.
there is no mediem cloud in the sky!
Cloud flashes. Spider lightening is the type of cloud flash that you can visibly see outside of the cloud.
The cirrus is the lowest type of cloud.
Cirrus is the wispiest cloud.
cloud to cloud lightning
a cumulus cloud
This type of cloud would be known as a stratus cloud
Stratus
Techinally the kind of cloud that spreads over the the sky in layers is the cumulonimbus cloud, but the cumulonimbus cloud spreads out in THICK layers over the sky. The question would be if the cumulonimbus cloud really does spread over the sky in layers.
Many cloud types can lead to a gray sky. Stratus is one of the more common ones.
nimbostratus cloud
A cirrostratus cloud is a high, thin, generally uniform stratiform type composed of ice-crystals. It is difficult to detect and is capable of forming halos when the cloud takes the form of thin cirrostratus nebulosus.
They look like fish scales. They can indicate unsettled weather. Often called a mackerel sky