Clouds are a mass of ice crystals or water drops suspended in the atmosphere. They are an important part of the water cycle. There are 10 types of clouds classified into 3 different levels:.
Clouds are formed when water from the ground or any water body gets evaporated in the form of water vapor by trapping the heat and leaving the water behind them cooler. Then this water vapor forms on the dust particles present in the air forming water drops by the method of condensation and such water drop combine to form clouds.
For example, clouds can form at a wide range of altitudes, while fog can only form near the ground level. A cloud is a body of water that you can see and is high in the sky.
This all depends on the direction of the wind and the pattern. If the water vapor is made in the sky and condenses high up then it will create a cloud. It goes around dust and smoke particles to make the clouds. They can also differ in weight and height.
When condensation happens near the surface of the earth, it creates fog or mist. It is a cloud that has just formed near the surface. What you feel when you walk through fog is what you feel walking through a cloud. The cold temperature and the unclearness are exactly what it would be like. Fog and mist are the same thing but have a difference when it comes to unclearness. If visibility is less than 1, meters then it is a fog. If visibility is greater than 1, meters it is called a mist.
Haze is different from the previous ones. It is dust or smoke that is in the air and invisible to the naked eye.
If it is dense enough to cause visibility issues, then it is a haze. These particles can sometimes cause the sky to red, which is seen during sunset. Radiation fog is when the heat on the surface of the Earth is put in the air during the evening. When the heat is transferred, water droplets are created. This can sometimes be called ground fog as well.
The fog that burns off when the morning sun comes is radiation fog. Advection happens when it is warm and moist in the air with a cool surface. This is called advection and describes how the fluid moves. The most well-known type of fog is radiation fog. Heat in the air mass radiates away, increasing relative humidity and allowing condensation to develop.
This will almost always form fog by dawn. These include strong winds nothing forms or fog is lifted into stratus , calm wind fog tends to settle out as dew , cloud cover to trap heat, a change in air mass, or drying of the ground. This type of fog can happen anywhere in the U. It almost always breaks up by midday, but sometimes it can become trapped in sheltered valleys during the winter months, particularly in the San Joaquin and Columbia valleys, and in the higher valleys of the Great Basin and Rockies.
Sometimes fog simply advects from one place to another. This often happens in places like the California coast, Puget Sound, and the Gulf of Mexico coast, where fog has formed in humid air and moves over cool ocean currents. By advection, we mean that almost everything is physically moved: temperatures, moisture, pollen, haze, smoke, stray mosquitoes, and anything else that is in the air parcels being moved.
This is called advection fog. Expect to see it sometimes when flying to places along the Gulf Coast or the West Coast. Fog may also develop in upslope flow on rising terrain and mountains from forced lifting and adiabatic cooling. Unlike radiation fog, this latter type of fog is often capped by overlying stratus and higher cloud layers, and it persists all day.
The lowest layers of cloud are the most dangerous, and form from all of the same factors as fog. Also upslope flow may manifest itself as low clouds rather than fog when dry air is present at the surface. It follows that the greatest risk of low clouds is along coastal areas, especially when there is onshore flow, and in and around mountains when winds are blowing upslope or across the mountains.
Isentropic lift is very common in the Great Lakes region, Midwest, and Northeast US, and this increases the chance of low cloud layers here, too. A battle plan for fog is guided by geography and weather patterns. This gives us a conceptual model to work from and a general idea of how the fog events progress. By comparing that to the current weather situation, we will know what to expect.
First identify if the current IMC is widespread or isolated. Widespread areas of poor weather are associated with synoptic-scale systems including fronts and broad areas of upslope flow.
Large IMC areas are a sign of synoptic-scale system and widespread fog and low ceilings. Conversely, radiation fog tends to be patchy or isolated. So when skies are clear and winds are light, a near-by alternate often works. In rare cases, especially with Western U. Selecting an airfield at a higher elevation will usually get you out of the fog and into VMC. With advection fog, your alternates should be downwind. Although coastal airports may indicate better visibility, advection fog is often a regional problem and those coastal sites are at risk of quickly going downhill.
Always get a weather briefing. There might be all the products you need on the Internet, but keep in mind that the weather briefers on the other end of the phone have already been spending hours watching conditions in their area and consulting with National Weather Service forecasters.
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