A barometer measures _________. A dropping barometer indicates an approaching _________:

A barometer is an instrument specifically designed to measure atmospheric pressure. This measurement is crucial for weather prediction, as changes in air pressure are tied directly to changes in weather patterns. A dropping barometer signifies that atmospheric pressure is decreasing, which is typically associated with an approaching low pressure system. Low pressure systems are often linked to stormy or unsettled weather conditions, such as rain and storms.

In contrast, a rising barometer often indicates that a high pressure system is moving in, usually bringing clearer skies and more stable weather. Understanding the relationship between barometric pressure and weather systems is essential for predicting weather changes effectively, especially for activities like sailing, where weather conditions can greatly affect safety and performance.