On a weather map, what does close spacing of isobars indicate?

On a weather map, what does close spacing of isobars indicate?

• A. Strong winds
• B. High humidity
• C. Light winds
• D. No winds

Answer: (A)

Close spacing of isobars indicates a steep pressure gradient, which drives strong winds. Isobars are lines of equal atmospheric pressure, so when they are packed tightly, the pressure changes quickly over a short distance. That sharp change creates a large pressure gradient force that pushes air more forcefully from high to low pressure, resulting in higher wind speeds at the surface. In the mid-latitudes, winds tend to flow roughly parallel to the isobars due to the Coriolis effect, but the magnitude of the wind increases as the spacing tightens. Conversely, widely spaced isobars mean a gentler gradient and lighter winds. Humidity isn’t what’s indicated by isobar spacing.

Close spacing of isobars indicates a steep pressure gradient, which drives strong winds. Isobars are lines of equal atmospheric pressure, so when they are packed tightly, the pressure changes quickly over a short distance. That sharp change creates a large pressure gradient force that pushes air more forcefully from high to low pressure, resulting in higher wind speeds at the surface. In the mid-latitudes, winds tend to flow roughly parallel to the isobars due to the Coriolis effect, but the magnitude of the wind increases as the spacing tightens. Conversely, widely spaced isobars mean a gentler gradient and lighter winds. Humidity isn’t what’s indicated by isobar spacing.