A warm front is characterized by what type of weather pattern?

A warm front is typically associated with a gradual transition in weather patterns, leading to steady and extended periods of precipitation. As a warm front approaches, warmer air moves in over cooler air. This lifting of the warm air can lead to consistent, light to moderate rain that can last for several hours or even days.

The reasoning behind option B being correct lies in the nature of warm fronts; they often produce widespread cloud cover and prolonged precipitation as the warm air rises slowly over the cooler air underneath. After the warm front has passed, conditions may remain cloudy and humid, indicating that the front often creates a blanket of clouds and moisture that can linger after the rain has stopped.

In contrast, the other options describe weather patterns that don't align with the characteristics of warm fronts. For example, sudden thunderstorms are more indicative of cold fronts, which are sharper and bring abrupt weather changes. Punctuated thunderstorms and a prolonged period of several days of rain with gradual clearing may also relate more to other types of fronts or atmospheric conditions. Therefore, the defining feature of a warm front, which is the steady, prolonged rain followed by humid conditions, makes option B the correct answer.