Uva Cachan dry foehn wind: adiabatic warming and seasonal flavor concentration in tea?

The world-famous "Uva Quality Season" (July to September) is driven by the Cachan—a warm, dry, foehn-type katabatic wind. Moisture-laden Southwest Monsoon clouds drop torrential rain on the western mountain slopes of Nuwara Eliya and Hatton. As dry air crests the central continental divide ridge and plunges down into the eastern Uva basin (Bandarawela and Demodara), it undergoes adiabatic compression, warming by 1°C per 100 meters. This hot, desiccating wind lowers relative humidity below 40%, placing tea bushes under sudden physiological moisture stress. The bush halts rapid vegetative flushing and concentrates aromatic terpenes (linalool and methyl salicylate), yielding iconic winter teas with a pungent, menthol-like eucalyptus aroma.