Arctic Oscillation - A climate phase that looks at the strength of the winds surrounding the arctic region. During a positive phase of the arctic oscillation, the ring of winds around the arctic remain strong, thereby holding the coldest air masses near the pole. During the negative phase these upper level winds weaken, allowing for the bitter cold arctic air masses to head further south across the northern hemisphere. Each switch in phase can last weeks or even months.

Twilight - Before sunrise and again after sunset there are intervals of time during which there is enough natural light provided by the upper atmosphere, which does receive direct sunlight and reflects part of it toward the Earth's surface. Some outdoor activities may be conducted without artificial illumination during these intervals of twilight. It is useful to have some means to set limits beyond which a certain activity should be assisted by artificial lighting.

Flood - A condition that occurs when water overflows the natural or artificial confines of a stream, river, or drainage ditch. Any ponding of water on what is normally dry land is also considered a flood. Floods can occur within minutes or hours of an excessive rainfall.

G.O.E.S. - An acronym that stands for Geostationary Operational Environmental Satellite. A geostationary satellite remains fixed over a specific area of the globe at an altitude of around 22,400 miles above the Earth's surface. These satellites give meteorologists the ability to constantly track weather systems that impact the region below them.

Transpiration - The process by which water escapes plants into the air and turns into water vapor. The rate at which plants lose water to the air increases as the temperature increases. Corn plants transpire at a rate higher than most plants. This means that corn needs more moisture to survive compared to most plant life.

Chromosphere - In relation to the sun, the chromosphere is the second of the 3 main layers of the sun's atmosphere. The chromosphere sits above the photosphere and below the solar transition region. The chromosphere is composed mainly of hydrogen gas that is hotter than 6000 degrees kelvin or 10,300 degrees on the fahrenheit scale.

Veering Wind - This is a way to describe how the wind direction changes with respect to height. A veering wind means that the wind direction is turning in a clockwise sense with increasing height. An example of a veering wind is when the wind at the surface is from the south and a few thousand feet above the surface the wind direction is from the west. The opposite of a veering wind is a backing wind.