The angular speed of a whirlwind in a tornado towards the centre

The angular speed of a whirlwind in a tornado increases as it moves towards the centre due to the principle of conservation of angular momentum. As air parcels spiral inward, their radial distance (r) from the axis of rotation decreases [1]. According to the law of conservation of angular momentum (L = Iω), where I is the moment of inertia and ω is the angular velocity, a reduction in the radius leads to a smaller moment of inertia. To keep the angular momentum constant, the angular velocity (ω) must increase significantly. This physical phenomenon explains why wind speeds accelerate as a mesocyclone contracts horizontally [2]. While the very center (the eye) may contain a region of relative calmness or solid-body rotation, the general progression of air moving from the outer layers toward the core involves a rapid increase in rotation speed.

Sources

1. [1] https://www.sciencedirect.com/science/article/abs/pii/S0169809525006337
2. [2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 8: Natural Hazards and Disaster Management > tornadoes > p. 54