Meteorology and atmospheric science terminology · MLC-0110
Meteorology and atmospheric science terms: L (110)
- La NiñaLa Niña, a phase of ENSO, is a periodic cooling of surface ocean waters in the eastern tropical Pacific along...
- lag1) The measure of the time between the center of mass of precipitation to the center of mass of runoff (on...
- lake breezeA thermally produced wind blowing during the day from the surface of a large lake to the shore, caused by the...
- Lake Effect Snow AdvisoryThis product is issued by the National Weather Service when pure lake effect snow (this is where the snow is...
- Lake Effect Snow SquallA local, intense, narrow band of moderate to heavy snow squall that can extend long distances inland. It may...
- Lake Effect Snow WarningThis product is issued by the National Weather Service when pure lake effect snow (this is where the snow is...
- Lake Effect StormA fall or winter storm that produces heavy but localized precipitation as a result of temperature differences...
- Lake Wind AdvisoryThis product is issued for sustained wind speeds, generally 20 to 29 mph, lasting for 1 hour or longer for...
- lake-effect snowSnow showers that are created when cold, dry air passes over a large warmer lake, such as one of the Great...
- LALs(L)ightning (A)ctivity (L)evels.
- LaminarSmooth, non-turbulent. Often used to describe cloud formations which appear to be shaped by a smooth flow of...
- laminar flowStreamline flow in which successive flow particles follow similar path lines and head loss varies with...
- land breezeA coastal breeze at night blowing from land to sea, caused by the difference in the rates of cooling of their...
- LandfallThe intersection of the surface center of a tropical cyclone with a coastline. Because the strongest winds in...
- landspout[Slang], a tornado that does not arise from organized storm-scale rotation and therefore is not associated...
- lapse rateThe rate of change of an atmospheric variable, usually temperature, with height. A steep lapse rate implies a...
- large scale(Synoptic Scale) Size scale referring generally to weather systems with horizontal dimensions of several...
- Last UpdateThe time and date in which the forecast was issued or updated. The forecast may be updated at any time as...
- LATLatitude- The location north or south in reference to the equator, which is designated at zero (0) degrees...
- latent heatHeat absorbed or released during a change of phase at constant temperature and pressure.
- Latent Heat FluxThe flux of heat from the earth's surface to the atmosphere that is associated with evaporation or...
- latitude(abbrev. LAT) The location north or south in reference to the equator, which is designated at zero (0)...
- LAWEB(Great Lakes Weather Broadcast) - A National Weather Service product containing an observation summary...
- Layer Composite Reflectivity AverageThis WSR-88D radar product displays the average reflectivities for a layer. Data is taken from all elevation...
- Layer Composite Reflectivity MaximumThis WSR-88D radar product displays the maximum reflectivities for a layer. Data is taken from all elevation...
- Layered HazeHaze produced when air pollution from multiple line, area or point sources is transported long distances to...
- LCD (Local Climatological Data)This National Climatic Data Center (NCDC) publication is produced monthly and annually for some 270 United...
- LCL1. Abbreviation for "local" or "locally"
- LDSLightning Detection System
- LDTLocal Daylight Time.
- leaderThe streamer which initiates the first phase of each stroke of a lightning discharge. The first stroke is led...
- Leader SpotIn solar-terrestrial terms, in a magnetically bipolar or multipolar sunspot group, the western part precedes...
- LeeThe side or part that is sheltered or turned away from the wind, such as with a mountain.
- lee waveThe wavelike effect, characterized by severe updrafts and downdrafts, that occurs in the lee of a mountain...
- Leeside LowExtratropical cyclones that form on the downwind (lee) side of a mountain chain. In the United States, they...
- LeewardThe side away from the wind. Compare windward.
- Left Exit RegionUsed interchangably with Left Front Quadrant; the area downstream from and to the left of an upper-level jet...
- Left Front QuadrantUsed interchangably with Left Exit Region; the area downstream from and to the left of an upper-level jet max...
- Left MoverA thunderstorm which moves to the left relative to the steering winds, and to other nearby thunderstorms...
- LengthIn hydrologic terms, the distance in the direction of flow between two specific points along a river, stream...
- Lentic SystemIn hydrologic terms, a nonflowing or standing body of fresh water, such as a lake or pond
- lenticular cloudA very smooth, round or oval, lens-shaped cloud that is often seen, singly or stacked in groups, near or in...
- Levee(Dike) In hydrologic terms, a long, narrow embankment usually built to protect land from flooding. If built...
- level of free convection(LFC) - The level at which a parcel of saturated air becomes warmer than the surrounding air and begins to...
- LEWPLine Echo Wave Pattern. A bulge in a thunderstorm line producing a wave-shaped "kink" in the line. The...
- LFCAn acronym for Level of Free Convection- the level at which a parcel of saturated air becomes warmer than the...
- LFTLift
- LGTLight
- LGWVLong Wave
- LILifted Index. A common measure of atmospheric instability. Its value is obtained by computing the temperature...
- lid1. (Also called cap.) A region of negative buoyancy below an existing level of free convection (LFC) where...
- LIFRLow Instrument Flight Rules
- lifted index(abbrev. LI)- A common measure of atmospheric instability. Its value is obtained by computing the temperature...
- lifting condensation level(LCL) - The level at which a parcel of moist air becomes saturated when it is lifted dry adiabatically.
- Light BridgeIn solar-terrestrial terms, it is observed in white light, a bright tongue or streaks penetra- ting or...
- Lightning(abbrev. LTNG) A visible electrical discharge produced by a thunderstorm. The discharge may occur within or...
- lightning channelThe irregular path through the air along which a lightning discharge occurs. A typical discharge of flash...
- lightning dischargeThe series of electrical processes by which charge is transferred along a channel of high ion density between...
- lightning strokeAny of a series of repeated electrical discharges comprising a single lightning discharge (strike)...
- Likely(abbrev. LKLY) In probability of precipitation statements, the equivalent of a 60 or 70 percent chance.
- LimbIn solar-terrestrial terms, the edge of the solar disk.
- Limb FlareIn solar-terrestrial terms, a solar flare seen at the edge (Limb) of the sun.
- LimnologyIn hydrologic terms, the branch of hydrology that pertains to the study of lakes
- line echo wave pattern(abbrev. LEWP) A radar echo pattern formed when a segment of a line of thunderstorms surges forward at an...
- Line SourceAn array of pollutant sources along a defined path that can be treated in dispersion models as an aggregate...
- Liquid Water EquivalentSame as Water Equivalent; the liquid content of solid precipitation that has accumulated on the ground (snow...
- lithometeorAtmospheric phenomena which affect the state of the atmosphere. They constitute dry particles that hang...
- lithosphereIn hydrologic terms, that part of the earth which is composed predominantly of rocks (either coherent or...
- Littoral ZoneIn hydrologic terms, the area on, or near the shore of a body water
- Live CapacityIn hydrologic terms, the total amount of storage capacity available in a reservoir for all purposes, from the...
- LIVVLifted Index Vertical Velocity
- LKLYLikely- In probability of precipitation statements, the equivalent of a 60 or 70 percent chance.
- LLJLow Level Jet - A region of relatively strong winds in the lower part of the atmosphere. Specifically, it...
- LLWSLow Level Wind Shear
- LMTDlimited
- LNLine
- Loaded Gun (Sounding)[Slang], a sounding characterized by extreme instability but containing a cap, such that explosive...
- Local Convective WindIn fire weather terminology, local thermally driven winds arising over a comparatively small area and...
- Lock & DamUsed in navigable rivers, lock and dams allow for large ships to move from one level of water to another.
- loftingA pattern of plume dispersion in a stable boundary layer topped by a neutral layer, in which the upper part...
- Long Term RetentionRetention of data for 5 years to satisfy requirements for local studies and to support litigation.
- longitudeThe location east or west in reference to the Prime Meridian, which is designated as zero (0) degrees...
- longwave radiationA term used to describe the infrared energy emitted by the earth and atmosphere at wavelengths between about...
- Longwave TroughA trough in the prevailing westerly flow aloft which is characterized by large length and (usually) long...
- Loop Prominence System(abbrev. LPS) In solar-terrestrial terms, a system of loop prominences associated with major flares.
- loopingA pattern of plume dispersion in an unstable atmosphere, in which the plume undergoes marked vertical...
- LOPRESlow pressure
- LORANLong Range Navigation, a system of long range navigation whereby latitude and longitude are determined from...
- Lotic SystemIn hydrologic terms, a flowing body of fresh water, such as a river or stream.
- lowA region of low pressure, marked as "L" on a weather map. A low center is usually accompanied by...
- low frequency(abbrev. LF) The portion of the radio frequency spectrum from 30 to 300 kHz.
- Low Pressure SystemAn area of a relative pressure minimum that has converging winds and rotates in the same direction as the...
- Low Water AdvisoryAn advisory to describe water levels which are significantly below average levels over the Great Lakes...
- Lowland FloodingIn hydrologic terms, inundation of low areas near the river, often rural, but may also occur in urban areas.
- low-level jet(abbrev. LLJ)- A region of relatively strong winds in the lower part of the atmosphere. Specifically, it...
- LP StormLow-Precipitation storm (or Low-Precipitation supercell). A supercell thunderstorm characterized by a...
- LPSLoop Prominence System- In solar-terrestrial terms, a system of loop prominences associated with major flares.
- LRGLarge
- LSRLocal Storm Report. A product issued by local NWS offices to inform users of reports of severe and/or...
- LSTLocal Standard Time
- LTDLimited
- LTLLittle
- LTLCGLittle Change
- LTNGLightning- A visible electrical discharge produced by a thunderstorm. The discharge may occur within or...
- LTRLater
- LTSTlatest
- LVLLevel
- LVLSlevels
- LWRLower
- lysimeterIn hydrologic terms, a device to measure the quantity or rate of downward water movement through a block of...
110 of 3,164 terms in Meteorology and atmospheric science terminology (MLC-0110). Request the full dataset.