Where are the strongest winds located in a jet stream?

The strongest winds in a jet stream are found in the center of the jet stream. This area is often referred to as the "core" of the jet stream, where the wind speeds are maximized due to the steep temperature gradient that exists at this level in the atmosphere. As the jet stream flows, the greatest contrast in temperatures—usually between warm tropical air and cold polar air—creates a rapid movement of air aloft. This results in the phenomenon known as geostrophic balance, where the pressure gradient force is balanced by the Coriolis effect, contributing to higher wind speeds.

The core of the jet stream can exhibit wind speeds exceeding 100 knots, especially during certain conditions like the presence of troughs and ridges in the upper-level flow. In contrast, winds tend to weaken as you move toward the edges or near the surface, which explains why wind speeds drop off away from the center. The dynamics of the atmosphere, including turbulence and friction, also play a role in reducing wind speeds outside the central core of the jet stream.