During which season is the subtropical jet at its highest altitude?

• A. Summer
• B. Winter
• C. Spring
• D. Fall

Answer: (B)

The subtropical jet stream is typically located at higher altitudes during the winter season. This phenomenon occurs because of the significant temperature gradients between the warm tropical air and the colder air masses over mid-latitude regions during this time of year. The stronger polar winds and reduced thermal convection in winter contribute to an increase in the altitude of the subtropical jet.

In contrast, during the summer months, the temperature gradients are less pronounced, leading to a lower altitude for the jet stream. Therefore, the subtropical jet is generally found at an elevated position in the atmosphere during winter as the conditions favor its elevated development and intensity. Understanding these seasonal variations is essential for predicting weather patterns and their impacts on aviation operations.