RatsA,
It was the instability of the air that caused the bumps. Hence the snow showers.
Kirstey,
There are two separate icing problems that may affect your aircraft. The first is airframe icing. If your airframe is at or colder than 0 degrees C then just like a car or anything else outside in such condititions, it may get ice on it if there is moisture in the air you fly through.
Bear in kind that it is possible for unfrozen moisture to exist below zero celsius (supercooled moisture). If it does, it's just waiting for your aircraft to come along to form a nucleus to freeze onto. It may affect the aerodynamics of the wings in particular, also your personal visibility through the transparencies, performance of the radio aerials, movement of the flying controls / flaps, undercarriage retraction and extension and braking systems. All not nice.
Over and above that, your engine has a carburettor with a venturi and evaporating petrol inside which causes a marked reduction in temperature within it. With an outside air temperature well above zero (actually to about plus 10C or higher ), you may still be getting carburettor ice forming. Remember to use carb. heat as recommended by the Flight Manual for your aircraft. This might be required in summer as well as now, depending on aircraft type.
Climbing through a layer of cold cloud can be OK if you are absolutely sure it is only a very thin layer and there is clear air above. Unfortunately, cloud has a nasty habit of thickening up once you are above it. To come down again you need a reduced throttle setting and this is when your carb is most likely to suffer from icing as the internal depression is highest.
The best advice is to stay below the zero degree level and stay on the ground if you aren't sure.
Last edited by ShyTorque; 9th January 2003 at 00:31.