I know many Aeronef players out there have been looking for ways to integrate weather and cloud effects iunto their games. Some have produced excellent cloud models, but not everyone has the time or inclination to do so.
I saw these smoke markers today (with an appropriately VSF-ish clockwork machine next to it!) and thought they may fit the bill for some players. They are Gale Force Nine’s Warmachine Cloud Effects Markers: "designed to effectively denote continuous Cloud Effects on the table top with a dynamic 3-D marker while still maintaining playability."
There are are two kinds, the smoke marker and this "wall of smoke" marker.
Be warned that they aren't cheap, and they may not be your cup to tea (...even with a slice of lemon added!) but if they do tickle your fancy, you can find out more here: