How are isobars usually drawn on a surface weather map?

Isobars, which represent lines of equal atmospheric pressure on surface weather maps, are typically drawn at specific intervals to effectively communicate pressure changes and systems in the atmosphere. The standard convention for drawing isobars is at intervals of 4 hectopascals. This spacing allows for a clear representation of pressure gradients, helping meteorologists and pilots understand weather conditions such as high and low-pressure systems.

Using this interval provides a balance: too wide a spacing might lead to a lack of detail in pressure distribution, while too narrow a spacing could clutter the map and make it difficult to interpret. The choice of 4 hectopascals strikes this balance, offering sufficient detail for analyzing weather patterns and their potential impact on flight operations without overwhelming the reader with excessive lines.