© Roger Colbeck
Matterhorn, Alps, Switzerland
Latitude: 45° 58' 36'' N
Longitude: 7° 39' 31'' E
27 February 2009 1221 (Local Time)
Image P/S code: P.25.1
Image I.D.: 6074
The banner cloud is a stationary orographic cloud attached to, and extending downwind from, an isolated mountain peak. The cloud appears like a flag, banner or pennant on the leeward side of the peak. This picture shows the classic banner cloud formed by the Matterhorn in the Alps.
The cloud forms in conditions of fairly strong wind and relatively moist air, due to a combination of reduced pressure downwind of the peak and uplift of air in lee eddies.
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