Final answer:
A weak pressure gradient on a weather map is displayed by isobars that are widely spaced, indicating a small pressure change over a large area.
Step-by-step explanation:
A weak pressure gradient on a pressure map is typically represented by isobars that are spaced relatively far apart from one another. Isobars are the grey lines on a weather map that connect points of equal atmospheric pressure. When these lines are far apart, it indicates that there is only a small change in pressure over a large area, which usually corresponds to lighter winds and more stable weather conditions. In contrast, tightly packed isobars indicate a strong pressure gradient, which is associated with strong winds and potentially stormy weather. Meteorologists use these pressure maps to describe and predict weather patterns, including the modeling of hurricanes and other large-scale weather events.