What atmospheric condition allows radiation fog to burn off during the day?

The correct answer is that higher temperatures lead to the burning off of radiation fog during the day. Radiation fog forms when the ground cools overnight, allowing moisture in the air near the surface to condense into tiny water droplets. As the sun rises and temperatures increase, the warming air causes the fog to evaporate, disrupting the fog layer and making it dissipate.

While increased wind speed can help disperse fog by mixing the air layers, it is primarily the rise in temperature that directly affects the process of evaporation. Low humidity would not effectively contribute to burning off fog because radiation fog is associated with saturated air near the surface. Additionally, cloud cover can inhibit temperature increases by blocking sunlight, which in turn can prolong the presence of fog. Thus, the key factor in allowing radiation fog to dissipate is indeed higher temperatures.