lines drawn on a synoptic weather map that connect points of equal barometric pressure. Isobars extend around areas of high and low pressure. Pressure gradient wind speeds are inversely proportional to the distance between the isobars. Tightly spaced isobars indicate strong winds. Widely spaced isobars indicate weaker winds. See also: geostrophic scale.

About the author:
Bob Roitblat is an avid sailor, writer and professional speaker. If you have any comments about this blog, or you are interested in having Bob to speak at your club, contact the author here:

You may also be interested in Bob’s other blog, At The Helm, that is focused on the owners of small-to-medium sized closely-held businesses.