What does a weak pressure gradient signify?

A weak pressure gradient indicates that the isobars, or lines of constant pressure on a weather map, are spaced far apart. This occurs when there is a small difference in atmospheric pressure over a given distance. Since the wind is driven by differences in pressure, a weak gradient leads to lighter winds, as the force pushing the air from high to low pressure is minimal.

In contrast, when isobars are close together, it signifies a strong pressure gradient, resulting in stronger winds. The other choices do not accurately describe the implications of a weak pressure gradient. Calm and stable air may occur in various conditions, but it is not exclusively linked to weak gradients. Similarly, a weak pressure gradient does not inherently suggest heavy precipitation; that depends on factors like moisture availability and additional atmospheric dynamics. Thus, the correct choice about the nature of a weak pressure gradient directly relates to the spacing of isobars.