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The physical behavior of a falling raindrop is governed by delicate fluid dynamics and thermodynamics, and oscillates with time. Despite this time‐variant nature, past observational and simulation studies have aimed to generalize parameterizations for describing rain microphysics bearing the assumption that raindrops fall at terminal speeds with an equilibrium shape. However, the applicability of this hypothesis in a realistic atmosphere that is inherently turbulent remains an open question. Here, we employ novel retrieval techniques to quantify the impact of turbulence on raindrop microphysics using long‐term in situ observations with careful assessment of the wind effect. We find that raindrop microphysics increasingly deviate from the equilibrium state as the turbulence dissipation rate increases, and this effect is more pronounced for large raindrops. We present turbulence‐invoked rain microphysical parameterizations which shed light on the complex interactions between turbulence dynamics and raindrop microphysics. Plain Language Summary: Raindrops are omnipresent in the atmosphere and play an essential role in the global hydrological cycle. The microphysics of raindrops, namely, shape, orientation and fall speed, have long been represented as a function of diameter with an equilibrium state. This simplification omits the impact of ubiquitous turbulence in the atmosphere. This study quantifies the deformation of raindrops under turbulent conditions. We find that the shape of large raindrops is more rounded and that raindrop oscillation is more pronounced in response to strong turbulence. Their fall speeds are significantly lower than the terminal speed, and the corresponding standard deviations are greater. Our work demonstrates the necessity of physically representing turbulence dynamics for accurate parameterization of raindrop microphysics via numerical simulations. Key Points: Raindrop microphysics increasingly deviate from the equilibrium state as the turbulence dissipation rate increasesLarge raindrops exhibit rounder shapes and lower fall speeds under strong turbulenceTurbulence‐invoked raindrop microphysics parameterizations are given [ABSTRACT FROM AUTHOR]