The nice cumulus clouds today made we wonder what types I better should avoid and what would be ok to enter. Obviously once it is a towering cumulus or a full blown Cb I want to stay well clear of it.
But… What about those wide cumulus clouds that form beautiful straights that are being used by glider pilots to travel distances? Their vertical extend is not that much but they certainly were created with quite some uplift movement.
Just try it out and see for yourself 
There will be some turbulence but not much else. Fly at a safe speed (at least 30 kt above the clean stall, but not higher than your maneuvering speed Va) and just keep your attitude level – don’t chase altitude and heading while experiencing moderate and severe turbulence. If the altitude excursions are more than 200ft and you are flying IFR, tell ATC about it (“Unable to maintain altitude due to turbulence”).
[ / serious ]
As long as you don’t hope to meet mermaids or undinae – a bit of hope on a sylphe is justified.
These little bits of white fluff can be very uncomfortable to fly in. Combine this with the IMC and passengers can get sick quite quickly. It’s also hard work for the pilot.
Unfortunately it may not be all that much better underneath them – that is an unfortunate consequence of a common type of summer wx. But once you get above them – even only just above – you get smooth air.
and be ready for icing if at 0°C or a bit below….the pieces of ice below were picked up at FL 100 during a minute or two…climb to FL 110 get us back to VMC
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And you don’t want too much more ice than that on a Mooney Michal….I bet you lost at least 10 to 15 kias looking at that pic…
Really?
I will lose around 10 kts with a barely perceptible scraping of ice….it’s my early warning sign
we didn´t check the speed loss, we were happy enjoy sun shine again…and you know, Mooney is that fast the you do not care to get a bit slower…
To answer the original question: Turbulence, rain and icing.
