Question 854Navigation General

The correct answer is D) a severe low pressure system. A barometric pressure reading of 28.60 inches of mercury (Hg) is considered very low, which typically indicates the presence of a severe low pressure system. Low pressure systems are associated with deteriorating weather conditions, such as increased winds, precipitation, and the potential for severe storms. This information is important for Coast Guard captains to understand in order to make informed decisions about vessel safety and navigation during adverse weather conditions. The other answer choices are incorrect because: A) a rapidly improving weather pattern would be associated with rising barometric pressure, not a low reading of 28.60 Hg; B) fair weather and calm conditions are typically associated with higher barometric pressure readings, not a low of 28.60 Hg; and C) while a low pressure system does indicate deteriorating weather, the specific reading of 28.60 Hg points to a severe low pressure system, not just general deterioration.