Question 1279Navigation General

The correct answer is A) high clouds gradually followed by lower thicker clouds. The approach of a warm front is typically characterized by the gradual development of high-level cirrus clouds, followed by the lowering and thickening of cloud cover as the front approaches. This progression of cloud types is the first indication a mariner will have of the warm front's approach. The other options are incorrect because they do not accurately describe the initial cloud patterns associated with a warm front. Large cumulonimbus clouds (B) are more indicative of a cold front, fog (C) is a possible later stage of the warm front's passage, and low dark clouds with rain (D) are more characteristic of the warm front's arrival, not the initial indications of its approach.