That’s anecdotal, though. The physics of clouds are an enormous field of study. That said, it’s often the case that there aren’t any clouds below the PBL, and in many cases you may be seeing more of a unitary parcel, with clouds moving relatively the same direction.
But in many cases clouds at 6000’ are often doing something different than those at 18,000 or 30,000’.
Get a good, surface-based supercell and you have them going all sorts of directions. In fact, that ingredient (helicity) is pretty much necessary for supercellular development. Other types of shear (speed and/or directional) are necessary for any sustained or severe convection.
Here’s a prime example out of Mojave, CA right now. Camera is pointed SSW. You can see a low layer moving right to left (eastward), while an mid layer is moving away from the camera, mostly southward.
What’s neat is we can correlate it to the current modeled skew-t - I marked on the right side about where the layer splits.
Here’s an even longer, more dramatic one out of Minden, NV, looking west toward the Sierra Escarpment on the east side of Lake Tahoe.
This one is exacerbated by orographic effects. But what you’re not seeing directly (but you can see shadows on the mid layer) is an upper layer that’s heading west-southwestbound, away from the camera, above the overcast mid layer.
Clouds are frikkin amazing and we should be encouraging devs to do them right, better. But you can see the complexity involved and my caution is we don’t set them up to make it worse driving our demands through an incomplete lens. And of course, balancing that with not letting perfect be the enemy of good, either. There is some definite low-hanging fruit that would vastly improve the experience.
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