Weather Glossary



Return


#  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 
J/kg Joules per kilogram, unit commonly used to represent CAPE and CIN.
January Thaw A period of mild weather popularly supposed to recur each year in late January.
Jet A fast-moving wind current surrounded by slower moving air.
Jet Max ( or Jet Streak) A point or area of relative maximum wind speeds within a jet stream.
Jet Streak Same as Jet Max; a point or area ("streak") of relative maximum wind speeds within a jet stream.
Jet Stream (abbrev. JSTR) Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds. The position and orientation of jet streams vary from day to day. General weather patterns (hot/cold, wet/dry) are related closely to the position, strength and orientation of the jet stream (or jet streams). A jet stream at low levels is known as a low-level jet.
Jet Stream Cirrus A loose term for filamentous cirrus that appears to radiate from a point in the sky, and exhibits characteristics associated with strong vertical wind shear, such as twisted or curved filaments.
Jet Wind Speed Profile A vertical wind speed profile characterized by a relatively narrow current of high winds with slower moving air above and below. A large wind (speed) shear occurs above and below the jet axis.
Jetty In hydrologic terms, a structure (e.g.; a pier, or mole of wood or stone) extending into a sea, lake, or river to influence the current or tide or to protect a harbor
JMA Japanese Meteorological Agency
Jokulhlaup In hydrologic terms, an Icelandic term meaning glacier dammed lake outburst flood
JSTR Jet Stream - Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds. The position and orientation of jet streams vary from day to day. General weather patterns (hot/cold, wet/dry) are related closely to the position, strength and orientation of the jet stream (or jet streams). A jet stream at low levels is known as a low-level jet.
Juvenile Water In hydrologic terms, water formed chemically within the earth and brought to the surface in intrusive rock