Storm Chasing Terms
Arm Chair or Couch Chasing: People chasing from the comfort of their home! They follow radar and velocity images while monitoring storm reports. Most of the time they do this and relay back information to chasers in the field!
Bears Cage: The area directly under a rotating wall cloud, very dangerous place to be. This is the area where a tornado is likely to form. Rain may be wrapping around this area to form a cage!
Beast: A very large and powerful supercell!
Bust: Either no storms form on a chase day, meaning you see no storms. Or storms form but you end up in the wrong area, and thus see nothing!
Clear Slot: A developing RFD. This RFD shows up as a visible clear slot on the rear of the storm.
Core Punching: Driving through the core of a storm(i.e. the core consists of heavy rain and hail)to get to a more favorable location!
Grunge/Grungy: This can either be lots of low hanging clouds called scuds, that hinder the view of storm features. Or it can mean that the storm is hard to see because of lots of haze and rain, making visibility, very poor! The haze aspect is caused be very high dewpoints(75 degrees or more), and very low LCLs.
Meso: Short for mesocyclone. Mesocyclone is the term used for the rotating updraft that defines wither the storm is a supercell or not(if it is rotating or not).
SDS: Storm deprivation syndrome! Happens in winter, and during long stretchs of inactivity in the weather. This affliction happens to most chasers when there is nothing to chase for an extended period of time. Very serious!
Scud: Low hanging clouds not attached to the cloud base.
Tail-end Charlie: Used to describe the tail-end storm. It is the south-end storm in a line of broken storms. It is the most likely storm to produce a tornado or severe weather. It is most likely to be severe because it is unhindered by storms forming to the south of it. Therefore it is free to ingest fresh warm, moist air coming up from the south!
Towering Cumulus: Towering cumulus cloud, close to becoming a cumulonimbus cloud.
Triple Point: The point at which warm, moist air and hot, dry air meet cold air! Usually where the dry line intersects the warm front and cold front on a weather map!
Severe weather Glossary
Downburst: Air decending downward at great velocitys then spreading outward in all directions. When this air hits the ground and spreads out, it spreads out as damaging winds. It often damages very localized and concentrated areas. The damage is often called straight line wind damage.
Downdraft: Air decending downward within a thunderstorm. Often accompanied by rain and hail. This air is usually cold and wet. But it can also be cold and dry or warm and dry or warm and wet, depends on the properties of the atmosphere.
Forward flank downdraft (FFD): A downward current of air with rain and hail in the middle and front area of a supercell, usually north or northeast of the mesocyclone.
Front: Leading edge of an air mass that is warmer or colder than the air in front of it. A cold front is the leading edge of cold air that is replacing warm air, and a warm front is the leading edge of warm air that is replacing cool air.
Funnel/Funnel cloud: A tornado that has not yet touched down. It is a cloud with a funnel shape but with no visible debris cloud underneath. If dust and a swirling debris cloud is seen underneath then it is a tornado.
Gust Front: The leading edge cool outflow air from a thunderstorm. Usually associated with a shelf cloud. This downward rolling air acts as a wedge to push up warm moist air into the thunderstorm.
Gustnado: A small, weak, and short lived tornado along the gust front of a thunderstorm.
Inflow: Warm, moist air flowing rapidly into a thunderstorm to feed it's updraft. The strongest inflow is usually associated with supercells.
Inflow jet: A river like flow of warm, moist air feeding into the thunderstorms updraft.
Landspout: A non-supercell tornado, not generated by a mesocyclone. Landspouts are typically small and weak, but some have been known to cause up to EF-2 damage. Landspouts are generated by rapidly growing cumulus and cumulonimbus clouds.
Lift: Rising motions in the air that help to generate thunderstorms. Lift can come from a variety of places. Lift can come from winds pushing together at the ground and forcing air upward, it can come from weather systems like fronts, and the heating of the earth by the sun.
Mesocyclone: The rotating circulation in a supercell thunderstorm. A typical mesocyclone develops in the supercell's updraft area and is 2 to 6 miles across. Tornadoes can develop within a mesocyclone.
Microburst: A concentrated burst of air rushing downward from a thunderstorm, doing wind damage in a small localized area. Similar to a "downburst," but affecting a smaller area.
Moisture: Water vapor in the air, but not visible to the naked eye. Dewpoint is one way of measuring the amount of moisture in the air.
Non-supercell tornado: A tornado not associated with the mesocyclone of a supercell thunderstorm. Most non-supercell tornadoes are weak and small, including gustnadoes and landspouts.
Outflow: Cool downdraft air moving outward from a thunderstorm.
Rear flank downdraft (RFD): A current of sinking air at the rear of a supercell thunderstorm, sometimes clearing out clouds and allowing sun to shine through. Unlike the rainy downdrafts at the front of a supercell, this downdraft often has little or no rain. Some RFDs can have strong winds.
Rotation: Air that moves or turns in a circle.
Squall line: A solid line of thunderstorms that can produce strong winds, heavy rain, and hail.
Supercell: A thunderstorm with a deep persistant rotating ciculation (called a mesocyclone) that helps the storm to persist and produce severe weather. Supercells can produce damaging winds, very large hail, and the strongest tornadoes.