WeatherQuestion 73 of 100
Which set of conditions is most characteristic of a stable air mass?
a.Cumuliform clouds, showery precipitation, and excellent visibility
b.Clear skies, strong vertical currents, and unrestricted visibility
c.Towering cumulus, gusty surface winds, and rapid temperature drops
d.Stratiform clouds, steady precipitation, haze, and smooth flying air
Explanation
Stable air resists vertical motion, so moisture and pollutants stay trapped near the surface, producing flat stratiform layers, steady drizzle or rain, haze that cuts visibility, and generally smooth flight conditions. That poor visibility is the main hazard for a remote pilot, since it can quickly drop below the 3 SM minimum. Cumuliform clouds, showers, gusts, and turbulence are all signatures of unstable air, not stable air.
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