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Tropical cyclone (TC) structure and intensity are strongly modulated by interactions with deep-layer vertical wind shear (VWS)—the vector difference between horizontal winds at 200 and 850 hPa. This paper presents a comprehensive review of more than a century of research on TC–VWS interactions. The literature broadly agrees that a TC vortex becomes vertically tilted, precipitation organizes into a wavenumber-1 asymmetric pattern, and thermal and kinematic asymmetries emerge when a TC encounters an environmental sheared flow. However, these responses depend on other factors, including the magnitude and direction of horizontal winds at other vertical levels between 200 and 850 hPa, the amount and location of dry environmental air, and the underlying sea surface temperature. While early studies investigated how VWS weakens TCs, an emerging line of research has focused on understanding how TCs intensify under moderate and strong VWS (i.e., shear magnitudes greater than 5 m s⁻¹). Modeling and observational studies have identified four pathways to intensification: vortex tilt reduction, vortex reformation, axisymmetrization of precipitation, and outflow blocking. These pathways may not be uniquely different because convection and vortex asymmetries are strongly coupled to each other. In addition to discussing these topics, this review presents open questions and recommendations for future research on TC–VWS interactions.

Understanding physical processes leading to rapid intensification (RI) of tropical cyclones (TCs) under environmental vertical wind shear is key to improving TC intensity forecasts. This study analyzes the thermodynamic processes that help saturate the TC inner core before RI onset using a column‐integrated moist static energy (MSE) framework. Results indicate that the nearly saturated inner core in the lower‐middle troposphere is achieved by an increase in the column‐integrated MSE, as column water vapor accumulates while the mean column temperature cools. The sign of the column‐integrated MSE tendency depends on the competition between surface enthalpy fluxes, radiation, and vertical wind shear‐induced ventilation effect. The reduction of ventilation above the boundary layer due to vertical alignment is crucial to accumulate the energy within the inner core region. A comparison of the RI simulation with a null simulation further highlights the impact of vortex structure on the thermodynamic state adjustment and TC intensification.