= Precipitation-driven foehn warming
{title2=$\Delta T\simeq(\Gamma_d-\Gamma_m)(H-z_c)$}
In the classical idealized parcel path, ascend dry adiabatically to condensation height $z_c$, continue at constant moist lapse rate $\Gamma_m$ to height $H>z_c$, lose condensate, then descend at dry lapse rate $\Gamma_d$ to the initial height. Adding the temperature changes gives the title. Complete condensate removal and an unsaturated descent are essential assumptions. A reversible dry ascent and descent with the same source air instead gives no net temperature increase at the same pressure.
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