What is the term for the wind that runs parallel to straight isobars?

The wind that runs parallel to straight isobars is known as the geostrophic wind. This occurs in the upper levels of the atmosphere where the pressure gradient force and the Coriolis force are in balance. Because of this balance, the geostrophic wind flows along the isobars rather than across them.

In the case of straight isobars, the geostrophic wind will maintain a consistent speed and direction, making it an important concept in meteorology for understanding large-scale wind patterns. This wind is typically associated with high altitudes where friction is negligible, allowing the theoretical balance of forces to operate effectively.

The term gradient wind refers to wind that flows along curved isobars and takes into account the centripetal force due to the curvature of the isobars, while surface winds are influenced by friction and typically do not flow parallel to isobars. Cyclostrophic wind is a term used for winds in small weather systems, such as tornadoes, where the centrifugal force is balanced by the pressure gradient force, but that does not apply to winds running along straight isobars.