How far should an aircraft maintain distance from thunderstorms?

The recommended distance an aircraft should maintain from thunderstorms is 20 miles or more upwind. This guideline is crucial for safety, as thunderstorms can produce severe turbulence, wind shear, lightning, hail, and tornadoes. Positioning the aircraft upwind allows for avoidance of hazardous conditions, giving pilots an added margin of safety to mitigate the risks associated with thunderstorm activity.

Maintaining a significant distance helps to ensure that the aircraft isn't affected by downdrafts or gust fronts that may extend well beyond the visible storm. While downwind distances can also be critical, the upwind position is particularly emphasized because it keeps the aircraft clear of the storm's outflow and any associated severe weather phenomena.

This understanding of storm dynamics is essential for pilots to navigate safely through potentially dangerous weather and is a critical element of flight training and operational procedures.