15 terms

Chapter 10, Thunderstorms and Tornadoes

a small storm often accompanied by heavy precipitation and frequent thunder and lightning
Airmass Thunderstorms
common durning summer afternoons or in coastal areas at night.
Cumulous Stage
The stage of a thunderstorm which is characterized by updrafts and large white puffy clouds.
Mature Stage
the second phase of a thunderstorm, where downdrafts move from the base of a cumulonimbus cloud and produce heavy precipitation. Tornadoes touch down during this phase of the storm.
Dissipating Stage
3rd stage of a thunderstorm, updraft weakens as gust front moves away so the precipitation falls until it is finished with no updraft to refuel it
Squall Line
long line of heavy thunderstorms that may occur just ahead of a fast-moving cold front
Severe Thunderstorm
A thunderstorm producing damaging winds or winds greater than 58 mph and/or hail an inch or greater in diameter.
Supercell Thunderstorm
These are the most severe of severe thunderstorms
Outflow Boundary
a line separating an air mass cooled by a thinderstorm and the surrounding air. it behaves like a cold fromnt and is characterized by a shift in wind and drop in temperature. in large thunderstorms, the outflow boundary may persist for more than 24 hours and cause instability that leads to new storms.
Gust Front
the boundary between cold and warm air at the surface during a thunderstorm which forces warm air up into the storm cell
small(less than 4 kn across), short-lived, straight line downbursts of wind that occur beneath some thunderstorms
Roll Clouds
1. Occurs in severe and fast moving thunderstorms
2. indicate presence of low level wind shear and extreme turbulence
an area on the flank of a supercell storm characterized by rotating clouds, precede tornado formation
a localized and violently destructive windstorm occurring over land characterized by a funnel-shaped cloud extending toward the ground
Doppler Effect
change in the apparent frequency of a wave as observer and source move toward or away from each other