Coast Guard Exams
Question 1319Navigation General70% to pass

When your barometer reading changes from 30.25 to 30.05 in a 12-hour period it indicates _______________.

AI Explanation
The correct answer is B) little or no immediate change. The change in barometric pressure from 30.25 to 30.05 inches of mercury over a 12-hour period indicates a relatively small change that is unlikely to result in significant weather changes in the immediate future. A change of 0.20 inches of mercury over 12 hours is considered a relatively small fluctuation that does not necessarily signal the onset of high winds, rapidly changing weather, or improving conditions. The other answer choices are incorrect because they suggest more dramatic weather changes, which are not supported by the relatively modest barometric pressure drop observed.

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