The most favorable conditions for their formation occur when the lowermost layer of air is unstable, but is capped by an inversion-by a stable layer of air. This often occurs when upper air is subsiding, such as under anticyclonic conditions, and is also frequently found when radiation fog has formed overnight. Convection occurs below the inversion, with air rising in thermals below the clouds and sinking in the air between the streets. Cloud streets provide glider pilots with lines of rising air, enabling them to fly straight for long distances while still climbing.
Cloud streets are usually more or less straight, but rarely cloud streets assume paisley patterns when the wind driving the clouds encounters an obstacle. Those cloud formations are known as von Kármán vortex streets. Although conventional cloud streets are clearly visible from the ground, large scale patterns such as these are seen best on satellite photographs.
Horizontal Convective Rolls in Cold Air over Water: Buoyancy Characteristics of Coherent Plumes Detected by an Airborne Radar
Sep 01, 2006; ABSTRACT Aircraft and airborne cloud radar data are used to describe the vertical structure of the convective boundary layer...