CHICOPEE, Mass. (WWLP) – There are two different types of fog that can happen, advection fog and radiation fog: advection fog notoriously happens in the winter and early springtime when the ground is cold and warmer air moves in, while radiation fog is what Western Massachusetts has been seeing a lot of recently and usually occurs in the fall and winter months.
Radiation fog only needs a few ingredients to form, clear skies and light winds. The ground cools the air to saturation, essentially creating a cloud on the ground, which is known as fog. The more and more that the air cools, the more intense the fog will get. The clear skies at night allow for temperatures to drop at the surface. This is because clouds act as a blanket, the more clouds the, the warmer the surface of the earth would be.
On the other hand, without any clouds, temperatures drop back, just like you would get cold without a blanket. The most favored areas for fog development are sheltered valleys because there is little to no wind in those locations. Wind would disrupt the formation of radiation fog. Radiation fog goes away under the sun’s rays the next day or that morning when the surface warms.