I believe your sentence relates to the "Butterfly effect" theory, a subset of chaos theory as applied to weather prediction. A small change in initial conditions leads to a large difference in the weather calculations. Cascade == pour rapidly and in large quantities like a waterfall. Metaphorical usage here, because literal cascades fall downwards, not upwards. Turbulent == in relation to air as a fluid, describes continual mixing, changing velocities and non-laminar flow. Turbulent features in air are turbulent winds like squalls, cyclones, hurricanes, typhoons, etc. So the uncertainties in how to calculate weather become bigger and bigger as you move 'up' the chain from small winds to increasingly bigger wind structures. The 'up(ward)' means "along the chain", not literally higher up in the atmosphere.

It's a fancy way of saying floting up threw feathers, can't say more with out context.