Hi Ian,

There's no simple rule of thumb to memorise all the details but if you get stuck you can make an educated guess at the options by taking it back to basic principles and work out the icing and turbulence to be expected:

First off, clouds are either stratiform or cumuliform and they are either high (cirrus), medium (alto) or low clouds.

To work out icing and turbulence, just remember, the more vertical development, the greater the convection within the cloud. So Cu type clouds are going to have more vertical development (and therefore turbulence) than flatter stratiform clouds. Thicker stratiform layers (such as nimbostratus) or strato-Cu are going to have more vertical development and turbulence than a nice thin layer of stratus.

The greater the vertical development of the cloud, the more turbulent the layer will be when you fly through it. Again, Cu types are going to be more turbulent than stratiform,, the severity of the turbulence dependent on the degree of vertical development. Apart fom that, the more vertical development in the cloud, the larger the water droplets that can be supported by updrafts within that cloud and so also the greater the chance of some kind of precipitation from that cloud as well.

Large droplets mean a greater chance of clear ice if you are flying above the freezing level. Smaller drops mean more chance of rime ice if you are above the freezing level. Go too high though and those drops will have already formed ice crystals. Remember, icing is only a problem if the liquid droplets freeze onto the airframe. If they are already frozen they don't present an icing problem.

Finally, a cloud with a lot of large droplets will appear darker and greyer than a cloud with smaller droplets.

Using these simple rules while memorising the attributes might help a bit.

Cheers,

Rich

Excellent advice Richard.

I've just completed the MET book sample questions again and my results have been much better.

Just to finish this off:
The book seems to consider 2-2500ft of vertical cloud development "shallow". What would be considered (roughly speaking) deep?

Thanks
Ian