Question 1226Navigation General

The correct answer is B) Dew point. Dew point is the most useful factor in predicting fog when compared to air temperature. Fog formation occurs when the air temperature drops to the dew point, causing water vapor in the air to condense into tiny water droplets. The closer the dew point is to the air temperature, the more likely fog will form. In contrast, absolute humidity, vapor pressure, and barometric pressure are less directly related to the specific conditions that lead to fog development. The other options are not as useful for predicting fog. Absolute humidity and vapor pressure provide information about the amount of water vapor in the air, but do not indicate how close the air temperature is to the saturation point. Barometric pressure is not a primary driver of fog formation.