Central Valley Fog Research

During the winter months, there are many different areas where fog occurs in the United States. States in the west, like California, Oregon, and Washington, it is not uncommon for there to be several consecutive days of fog that form overnight and disappear in the mid-morning or early afternoon. Places along the Pacific Coast such as Morro Bay, California and San Francisco, California tend to see a considerable amount of fog that travels over the water and move inland. On the East Coast, there is not as much widespread fog, but rather it is concentrated north in the state of Maine (Fog in the United States). Maine averages 3,000 hours of fog per year in Moose Peak and Nantucket Island. Because of the proximity to the Atlantic Ocean, there is …show more content…
The fog can last for several days at a time, making it dangerous for residents and people that are traveling through the valley. For Californians, the fog that takes place is commonly know as “tule fog” because it is where the tule grass wetlands are (Fog in the US). The Central Valley spreads over the middle of California beginning north in Redding, which is in the Sacramento Valley, and extending south to Bakersfield, which is in the San Joaquin Valley. The Sierra Nevada Mountain rage and the Cascade Mountain range border the east of the valley and the Coastal Mountains border the west. Because of this, radiation fogs occur and are relentlessly trapped between the mountains (California DOT Fog). Foggy days have both positive and negative aspects in the Central Valley. Fog in the Central Valley is seemingly iconic in the winter and early spring months. There is a calming aspect to the fog after several months of temperatures summer the that exceed 100 degrees Fahrenheit. There is also an immense amount of beauty when the fruit trees are covered a foggy mist on a cool morning. However, there tends to be more negative aspects because of the dangers that come along with having dense fog for long periods of time (Ahrens). Any person that has lived in California is aware of what fog can potentially do while driving. California Highway 99 extends north and …show more content…
The two that are most common that form in California are radiation and advection fogs. Radiation fog, or more commonly known as ground fog, is created when there is a layer of heavy damp air that is just above the ground with dry air that is over the top of it. This type of fog occurs best when there is a slight wind to increase the formation of the fog, but it can also happen on a cold clear night. If there is too much movement in the air, the formation of radiation fog will not occur because the air will mix (Ahrens). The fog can develop and last through six to twelve-hour period beginning in the late evening and lasting until mid morning (Processing of atmospheric). Because the cool moist air is sitting above the ground, it is quickly cooled and begins to absorb the radiation that is from the earth. If the two layers of cool moist air and warmer dry air do not mix, inversion occurs and the lower layer will saturate and hold the water in the air to form a radiation fog. As the ground gets colder, the fog above it will continue to get more and more dense (Ahrens). Advection fog takes place when a large mass of warm damp air travels across a significantly colder surface, such as the Pacific Ocean. The moist air traveling across the cold surface is quickly saturated and therefore a dense fog is created. A great amount of air movement is