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How does the jet stream contribute to tornado-producing storms?

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Weather forecasting Doppler radars, such as this one operated by the U.S. National Weather Service at New Underwood, South Dakota, extract the Doppler frequency shift of the echo produced by a moving target by noting how much the frequency of the received signal differs from the frequency of the signal that was transmitted.

The jet stream—a narrow band of high-speed air located in the upper troposphere—is a critical factor in the development of tornado-producing storms.12

While tornadoes require specific conditions such as atmospheric instability and a veering wind profile at low and middle levels, the jet stream contributes by providing the necessary high-altitude winds. These strong upper-level winds work in tandem with lower-level wind patterns to create the essential "spin" in the atmosphere.1

Specifically, the interaction between a persistent updraft and these wind profiles allows diffuse atmospheric rotation to be tilted and concentrated into a vertical axis. This process can lead to the formation of a mesocyclone, a rotating region within a thunderstorm that serves as the precursor to many tornadoes. Meteorologists monitor the intensity and movement of the jet stream alongside other atmospheric variables to identify regions where conditions are favorable for these severe storms.31