Radiation Fog - This type of fog forms at night under clear skies with calm winds. Under these conditions heat that was absorbed by the earth's surface during the day is allowed to radiate back into space. As the earth's surface continues to cool, provided a deep enough layer of moist air is present near the ground, the humidity will reach 100% and fog will form. Radiation fog varies in depth from 3 feet to about 1,000 feet and is always found at ground level and usually remains stationary. This type of fog can reduce visibility to near zero at times and make driving very hazardous.

Coalescence - The precipitation process by which water droplets in a cloud collide and stick together to become large enough to form raindrops. This is the way most precipitation is generated in tropical climates.

Drizzle - A type of precipitation consisting of numerous tiny droplets of water less than 0.5 mm in diameter. Drizzle typically falls when there is fog or low stratus cloud cover over an area.

Cirrus clouds - High-level cloud cover that appears wispy and feathery, and is composed entirely of ice crystals. Cirrus clouds are commonly seen during fair weather.

Zodiacal Light - A softly luminous cone of white light visible from an hour or so after sunset or before dawn. The cause of this pre-dawn or post-dusk light is created by sunlight that reflects off of grains of dust in space between the Earth and the Sun. To an unknowing observer it can be mistaken for a glare of city lights on the distant horizon.

Haze - Haze can be composed of fine dust, smoke, salt particles, or atmospheric pollutants. These particles become coated with water droplets giving them an even larger bearing on sky conditions and visibility. Haze gives the sky a milky tone due to the veil it puts between us and the sun.

Downburst - A strong wind that is the result of a strong downdraft that occurs beneath a severe thunderstorm. Downdrafts are pockets of air that accelerate downward from a thunderstorm, and then spread horizontally when they reach the ground. The resultant strong winds that are experienced at the surface is the downburst.