Weather Glossary - K

Search

Katabatic wind

A local wind which develops due to cool, dense air flowing downhill. The cooler air is generally a result of night time radiational cooling in the lower layers of the atmosphere, but katabatic winds also occur over snow fields and glaciers. See also anabatic winds.

Katafront

A front where the warm air descends the frontal surface, except in the low layers.

Kelvin

Unit of thermodynamic temperature. Zero Kelvin is absolute zero (-273.15°C). Temperatures in Kelvin can be obtained from temperatures in Celsius by the formulae K=C+273.2.

Kelvin-Helmholtz billows

A phenomenon that occurs in a high-shear environment between two layers of fluid which are stably stratified (i.e. a denser fluid beneath a lighter fluid).

Kinetic energy

The energy a body possesses as a consequence of its motion. Defined as half the product of its mass and the square of its speed.

Knot

The unit of speed equal to 1 nautical mile/hour, or 1.85 km/h. The knot is commonly used to report wind speed and ocean current speed.

Knuckles

[Slang] Lumpy protrusions on the edges, and sometimes the underside, of a thunderstorm anvil. They usually appear on the upwind side of a back-sheared anvil, and indicate rapid expansion of the anvil due to the presence of a very strong updraft. They are not mammatus clouds. See also cumuliform anvil, anvil rollover.

Køppen's classification of climates

Classification of climate based on annual and monthly means of temperature and precipitation which also takes into account the vegetation limits. It is a tool for presenting the world pattern of climate and for identifying important deviations from this pattern.

Display Your Local Weather

Weather News

Canberra's urban forest threatened by extreme heat, drought — and drivers parking on nature strips

09:15 EDT

If you park your car on the nature strip, beware — you're killing Canberra's street trees and the ACT Government will track you down.

St George flooding expected to affect nearly 20 homes when Balonne River peaks

08:43 EDT

Nearly 20 homes in low-lying areas of St George in Queensland's southern inland are at risk of flooding when the Balonne River reaches its expected peak later today.

WA storm prompts big clean-up as Perth dashcam video shows large tree crushing car

20:25 EDT

Dramatic footage has emerged of a lucky escape on Perth's roads during a destructive storm authorities have described as the most severe to hit the city in almost a decade.