Convective cloud features in typical synoptic environments: The Spanish Plume
One typical occurence of Cbs and Mesoscale Convective Systems is within the area of hot air over Spain, in front of an approaching Cold Front.
The Spanish Plume is a geographically specific case of convection, in which intensive Cb and Mesoscale Convective System form over the Spanish plateau and Western Europe. The Spanish Plume is, by definition, an incident where warm air is lifted from the Spanish plateau ahead of an eastward-moving upper-level trough over the Bay of Biscay. The strong heating of air near the surface over the Spanish plateau causes convergence and ascent, enhanced by the dynamical forcing of the eastwards moving upper-level trough. This leads to the formation of a thermal low over the Iberian Peninsula. The thermal low sets up a low-level cyclonic flow over the peninsula, which includes the formation of a convergence line over the plateau. This induces the advection of cooler air and descending motion across the coastal areas of the Iberian Peninsula and Western France from the Bay of Biscay and warm air advection over the interior of the peninsula. Therefore in the area east of the surface trough the advection of warm air enhances the ascents within the warm plume.