Hourly weather observations that include sea-level pressure are plotted or printed on weather maps. Isobars are drawn by connecting points having equal sea-level air pressure, using a specified ...

A bar is a metric unit of pressure and isobars are lines on a weather map that connect points of equal air pressure. Because variations in air pressure drive atmospheric winds, isobars give ...

An isobar is a line of constant pressure. These lines are often measured in 2, 4, or 10 millibar increments. When you see lots of isobars over an area, most likely that area is experiencing lots of ...