Spanish plume

The Spanish Plume (Penacho Ibérico in Spanish and Spaanse Pluim in Dutch) is a weather pattern in which a plume of warm air moves from the Iberian plateau or the Sahara to northwest Europe giving rise to severe thunderstorms. This meteorological pattern can lead to extreme high temperatures and intense rainfall during the summer months, with potential for flash flooding, damaging hail storms and tornado formation.

A similar pattern, though on a larger scale, is the Mexican plume in the south west USA, where hot dry air from the Mexican highlands acts as a cap to convection until lifted over Texas, Arkansas and Oklahoma.

In Finland and the Baltic states meteorologists have observed a situation conducive to severe summer storm development which occurs when a warm moist air mass flows into the region from the south or south east under the influence of an upper-level trough. These conditions have some similarities to the Spanish plume. The synoptic conditions see a low over southern Norway, bringing warm south and southwesterly flows of air up from the inner continental areas of Russia and Belarus.

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Wikipedia