STORM CHASERS

Glossary



CA - Cloud to air lightning

Cb - Cumulonimbus

CC - Cloud to cloud lightning

CG - Cloud to ground lightning

Cj - Cumulus Congestus

Cu - Cumulus

Funnel cloud (FC) - The condensation funnel of a vortex that does not reach the ground

Gust Front - Often cool, fresh winds come out of a thunderstorm, accompanied by a line of cloud, sometimes called a shelf cloud

IC - Inter-cloud lightning - lightning that occurs inside the cloud however visible 'bolts' can't be seen. Can be called "Sheet lightning"

Landspout Tornado - A tornado that is formed by surface vorticity being stretched upwards. Often referred to as spin up tornadoes, this is a non supercell process

Mesocyclone - A vortex of air, approximately 2 to 10 km in diameter, within a thunderstorm

Multi-cell - A thunderstorm made up of two or more single-cell storms

Sferics - Crackles you here on the AM band of the radio when lightning goes off, the stronger they sound the closer a storm is. If they are weak storms are generally quite far away

Single-cell - A storm consisting of a single 'cell'

Supercell - A severe thunderstorm with a sustained rotating updraft

Supercell Tornado - A tornado that is formed from supercell thunderstorm processes. The mesocyclone of a supercell thunderstorm is drawn down to the surface.

Time - On this site I quote times as 0000z or 0130z etc. "z" is just another term for UTC (Coordinated Universal Time) or GMT (Greenwich Mean Time). So for e.g. when you see 0100z it means 1.00pm (midday) in NZST (New Zealand Standard Time) and 2.00pm in NZDT (New Zealand Daylight Time). NZDT commences on the last Sunday in September, when 2.00am becomes 3.00am, and it ends on the first Sunday in April, when 3.00am becomes 2.00am

Tornado - A vortex that extends from the cloud base to the ground. The condensation funnel may or may not reach the ground but there is visible circulation on the ground

Waterspout - A vortex over water. A waterspout is termed a tornado if it makes landfall. The process of waterspout formation is often non supercellular

Wind shear - There are two types:

Directional shear which refers to the air changing direction with height

Speed shear which refers the wind speed changing with heigh


For all technical lingo like lifted index and CAPE go to http://www.theweatherprediction.com. Use the "Search this site with google box", select "www.theweatherprediction.com" then type in what you need to find out about.