Rainbow - An arc of concentric colored bands formed by refraction that occurs when sunlight passes through raindrops. Anytime you see it raining while the sun is out, there will almost always be a rainbow. Just position yourself with your back to where the sun is shining and you will find it.

Land Breeze - A land breeze is an off shore wind, meaning the wind blows from the land out to sea. It occurs at night when the land becomes sufficiently colder than the air over the water. Land breezes are most likely to occur on clear, calm nights. The opposite of a land breeze is a sea breeze.

Mesopause - This is the portion of the Earth's atmosphere that divides the mesosphere from the thermosphere. The mesopause is where the temperature of the atmosphere reaches its minimum. The coldest temperatures on Earth are found here as temperatures can fall to as low as -148F.

Derecho - A widespread and usually fast-moving complex of thunderstorms that produce damaging straight-line winds. These systems are long lived, as the swath of wind damage associated with them extends for hundreds of miles. Wind gusts can range from 60 to over 100 mph in a derecho.

Dew - Water that has condensed onto objects near the ground when the surface temperature of the object falls below the dew point. The most common surfaces that dew will form on are grasses and other vegetation. Dew can be an important source of moisture for plants during a drought.

Synoptic Scale - In meteorology this refers to the study of large scale systems that develop in the atmosphere. Major cyclones and their associated fronts are a commonly studied feature in synoptic meteorology. In order to be on the synoptic scale, a system must stretch across a distance of at least 600 miles.

Anvil - The flat, spreading top of a cumulonimbus cloud, often shaped like an anvil. Anvils are a result of strong winds near the top of the thunderstorm. Thunderstorm anvils may spread hundreds of miles downwind from the thunderstorm itself, and sometimes may spread upwind.