Turbulence in the clouds

C172Heavy

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Got a question about turbulence in the clouds vs. not in the clouds.

Is the turbulence in a cumulus cloud the same as the turbulence just below the cloud?

My thinking is this. The updraft or whatever that created the cloud has to start below where the cloud is forming, the cloud just simply starts forming where the air temp reaches the dewpoint. Does the saturated adiabatic lapse rate do something weird to the airflow? Therefore, shoudn't the turbulence be about the same directly under a given cumulus build up as it would be inside the cloud? This threads assumes buildups that are not yet thunderstorms.

I obviously don't have much experience with this, just wondering what everyone else thinks or knows about this.

Thanks.
 

cvsfly

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Clouds and weather are a dynamic thing. It is constantly changing (especially cumulus types). Expect as much or more turbulence inside as below. Then you may get lucky one day going through a CU to "prove" that wrong. It may appear slightly more comfortable below because your eyes can see what the body is feeling.
 

BigFlyr

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I'm no meteorologist but I can tell you from experience 99% of the time, any cloud you see will have more turbulence in it than under it or around it. This is especially true with a well defined cumulus cloud. Maybe its because a cumulus cloud typically has an updraft under it but inside the cloud itself, there are both updrafts and downdrafts.
 

Speedtree

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Hard to say unless you find one big enough and fly into it and then down out of it. (not neccessarily a good idea) I have received some nice jolts flying below a dark cumulus cloud but I never bothered to find out whether is was worse inside. Your logic makes sense to me without going into too much thought. I know I deviate pretty close to some when going around the build-up from the top and often we don't feel a thing.

The passengers would rather have us stay out of the turbulence as much as possible so I don't flirt with it too much.
 

tarp

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Good question.

I'm with the others - you just don't know. There are too many variables beside the lapse rate. You've got winds aloft, moisture content, precipitation (and therefore dissipation), latent heat, upslope or oragraphic anomolies.

After how many years this has been, just basically be aware that Mother Nature can do anything she wants at any time. In clear air, in clouds - doesn't matter. I'm particularly fond of stratus clouds when they aren't too close to the ground and I'm particularly wary of cumulous clouds especially when they loom higher than my airplane!

I have climbed through clouds that have given me a good thumping all the way up to and including the last ten feet of their height. I have flown into bright sunny looking clouds that didn't do anything until I found that they had a deep green colored center with enough water that I thought I had ditched in the ocean and was now submerged. I have steeled myself for the jolts from a towering cumy cloud and had the airplane basically rise and dip about ten feet.

There is only one truth that I've found in all of this and that is that nature does have a balance. If you enter a cloud and suddenly find yourself fighting updrafts, get ready because somewhere ahead you've got an equal fight against downdrafts. If the stormscope or radar is painting something ahead, turn the airplane - you'll really be happy you did.
 

FLYnMONKEYS

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99% of the time a cumuloform cloud will give you more of a bump if you go through it. What you have to look for if you go underneath it is something that can tell you there is outflow. A roll cloud or something else that ID's a gust front would be a good indication not to go under it, but if a cumuloform cloud doesn't have a lot of vertical development chances are you can go under it without incident..... If it has a lot of vertical development your best bet is to go around (windward side) or over the top (1000ft for every 10 kts the cell is moving) . Another thing to look at is how much contoring the cloud has, if it looks as rippled and dimpled as a 600lb women in a bikini stay away. But if it's just a fair weather cumulus cloud blast through it and get your feet wet, you'll need all the actual time you can get.
 

Austpilot

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Some of the worst turbulence I have ever encountered was in cumulus clouds. I remember flying through a line of developing Cu's(caught by surprise) in an "A" model Saab one afternoon and I can honestly say that the EADI was making me "sea sick" plus at a climb IAS of 160kts we got a stickshaker. Generally speaking I have found the bumps more severe in the clouds themselves. On days where you have fair weather Cu's you will get the obligatory updraught that the gliding fraternity hanker after if you fly underneath the cloud. Never flown under anything that looks grey and nasty because of fear of microburst - so can't answer that one.

This is easier said than done, but if you are caught in the grips of a developing Cu/Cunim, don't chase IAS or altitude - let it ride,slow down to Vb or Va in some aeroplanes and just hold attitude, and keep flying a straight path - don't turn around - the quickest way out of the bumps is a staright line (generally speaking).

Those of you out there that have flown the Saab 340 would know how good the autopilot is in turbulence - a real gem of an aeroplane.


Hope this helps.
 
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