Meteorology and atmospheric science terminology · MLC-0110

Meteorology and atmospheric science terms: N (294)

• NNorth
• NACA Standard AtmosphereA theoretical model of the Earth's atmosphere that defines standard values for atmospheric properties such as...
• Nacreous cloudsRare, iridescent clouds that form in the lower stratosphere, at altitudes between 15 and 25 kilometers. They...
• NadirThe point on the ground directly beneath an aircraft or satellite, corresponding to a viewing angle of zero...
• NAMThe operational North American Meso (NAM, formerly Eta) is run four times per day (00,06,12,18Z), all cycles...
• Nanotesla (nT)A unit of magnetism equal to 10^(-9) tesla, equivalent to a gamma (10^(-5) gauss).
• Nansen bottleA device used in oceanography to collect water samples from specific depths and to measure water temperature...
• Nansen castA historical oceanographic technique for collecting water samples and measuring temperature at specific...
• NAONorth Atlantic Oscillation - the NAO is a large-scale fluctuation in atmospheric pressure between the...
• NAO indexThis index measures the anomalies in sea level pressure between the Icelandic low pressure system and the...
• NappeA sheet-like mass of air that has been thrust over another, typically warmer and less dense air moving over a...
• NarbonnaisA strong, cold, and dry northwesterly wind that blows through the Aude valley in the Languedoc region of...
• Narrowband radiationElectromagnetic radiation that occupies a relatively small range of frequencies or wavelengths within the...
• Narrow-sector recorderA direction-finding receiver that records radio atmospherics, the impulsive radio noise from lightning...
• NASA ScatterometerA spaceborne radar instrument designed to measure ocean surface wind speed and direction by observing the...
• N'aschiA cold, dry, and often violent northeasterly wind that occurs along the northern coast of the Persian Gulf...
• National Ambient Air Quality StandardsPollutant concentration limits established by the U.S. Environmental Protection Agency (EPA) under the Clean...
• National Blend of ModelsThe National Blend of Models (NBM) is a nationally consistent and skillful suite of calibrated forecast...
• National Climatic Data CenterThe agency that archives climatic data from the National Oceanic and Atmospheric Administration, as well as...
• National Digital Forecast Database(NDFD)- The National Weather Service's NDFD provides access to gridded forecasts of sensible weather elements...
• National Fire Danger Rating SystemA uniform fire danger rating system used in the United States that focuses on the environmental factors that...
• National Flood SummaryThis NWS daily product (abbreviated FLN) contains nationwide information on current flood conditions. It is...
• National Hurricane CenterOne of three branches of the Tropical Prediction Center (TPC). This center maintains a continuous watch on...
• National Hurricane Operations Plan(NHOP) - The NHOP is issued annually by the Federal Coordinator for Meteorological Services and Supporting...
• National Hydrologic DiscussionA discussion of the current and forecast hydrologic conditions across the nation, including a variety of...
• National Severe Storms LaboratoryThis is one of NOAA's internationally known Environmental Research Laboratories, leading the way in...
• National standard barometerA highly accurate barometer maintained by a national meteorological service or standards laboratory, serving...
• National Tidal Datum EpochA specific 19-year period chosen by the National Oceanic and Atmospheric Administration (NOAA) over which...
• National Water ModelA hydrologic modelling framework that simulates observed and forecast streamflow over the entire continental...
• National Water Model Medium-Range Forecast (NWM MRF)A 10-day streamflow forecast for the over 3.6 million waterway miles across the Nation, forced by the GFS and...
• National Water Model Short-Range Forecast (NWM SRF)An 18-hour streamflow forecast for the over 3.4 million waterway miles across the Nation, forced by the HRRR...
• National Weather and Crop SummaryA product of the National Agricultural Statistics Service, Agricultural Statistics Board, and U.S. Department...
• Natural controlA natural feature of a stream channel, such as a rock ledge, riffle or narrowing, that fixes the relation...
• Natural coordinatesA curvilinear coordinate system where one axis is aligned with the instantaneous velocity vector of a fluid...
• Natural flowThe flow of water in a river or stream that would occur without any human-induced alterations, such as...
• Natural frequencyThe inherent oscillation rate of a system when it is disturbed from its equilibrium and allowed to oscillate...
• Natural remanent magnetizationThe permanent magnetism of rocks and sediments acquired from the Earth's magnetic field at the time of their...
• Natural sulfur cycleThe biogeochemical process describing the movement of sulfur compounds through the atmosphere, hydrosphere...
• Natural synoptic periodA duration of time during which the large-scale atmospheric circulation patterns over a specific region...
• Natural synoptic regionAn extensive geographical area within which atmospheric processes exhibit a high degree of coherence and...
• Natural synoptic seasonA division of the year based on recurring large-scale atmospheric circulation patterns and associated weather...
• NauluA sudden, brief rain shower of the Hawaiian Islands, and the shower cloud that brings it, tied in traditional...
• Nautical dawnThe time at which the sun is 12 degrees below the horizon in the morning. Nautical dawn is defined as that...
• Nautical duskThe time at which the sun is 12 degrees below the horizon in the evening. At this time, objects are no longer...
• Nautical mileA unit of length used in marine and aerial navigation, defined as exactly 1,852 meters (approximately 6,076...
• Nautical systemA set of conventions and units of measurement used in marine weather forecasting and navigation. It provides...
• Nautical twilightThe period of twilight when the center of the sun is between 6 and 12 degrees below the horizon. During this...
• Navier-Stokes equationsA set of nonlinear partial differential equations that describe the motion of viscous fluid substances, based...
• Navigable semicircleThe half of a tropical cyclone, relative to its direction of motion, where the wind speeds are generally...
• NavigationThe process of planning and following a route from one place to another, particularly in the context of...
• Navigation methodsIn hydrologic terms, there are three basic methods of providing and managing inland waterways - 1)...
• NAVTEXAn international automated medium frequency (518 kHz) direct-printing service for delivery of navigational...
• NAVTEX forecast(NAV) - A National Weather Service marine forecast combining various Coastal Waters and Offshore forecasts...
• NBNDNorthbound
• NC1. No change
• NCARNational Center for Atmospheric Research
• NCCFNOAA Central Computer Facility
• NCDCNational Climatic Data Center
• NCEPNational Centers for Environmental Prediction. A part of the National Weather Service which provides...
• NDBCNational Data Buoy Center
• NDFD(National Digital Forecast Database) - The National Weather Service's NDFD provides access to gridded...
• NDVIThe Normalized Difference Vegetation Index, a graphical indicator used to analyze remote sensing...
• NENortheast
• Neap rangeThe relatively small difference between high and low tide that occurs during neap tides. This reduced tidal...
• Neap tideA tide characterized by a smaller than average tidal range, occurring twice a month when the moon is in its...
• Near galeA wind speed category on the Beaufort scale, corresponding to a force 7 wind. It is characterized by speeds...
• Near-infraredThe portion of the electromagnetic spectrum with wavelengths longer than visible light but shorter than...
• Near-infrared radiationElectromagnetic radiation with wavelengths longer than visible light but shorter than mid-infrared radiation...
• Nearshore forecast(NSH) - National Weather Service seasonal marine forecasts for an areas of the Great Lakes extending from a...
• NebulosusA cloud species characterized by a hazy, indistinct, or veil-like appearance, lacking clear details or...
• NECNecessary
• Needle iceA needle-shaped column of ice that grows on the ground surface when soil water, still liquid in soil warmer...
• NEGNegative
• Negative cloud-to-ground lightningA type of lightning discharge where negative charge is transferred from the cloud to the ground. This is the...
• Negative feedbackA process within a system where the output of the system acts to reduce or counteract the initial change...
• Negative viscosityA theoretical concept where a fluid flow exhibits an apparent transfer of kinetic energy from smaller scales...
• Negative vorticity advection(Abbrev. NVA) - the advection of lower values of vorticity into an area.
• Negative-tilt TroughAn upper level system which is tilted to the west with increasing latitude (i.e., with an axis from southeast...
• NELYNortheasterly
• NeoglacialA period of renewed glacial expansion and cooler temperatures that followed the Holocene Climatic Optimum...
• NeonA noble gas that is a trace component of Earth's atmosphere, making up about 18 parts per million by volume...
• NeperA logarithmic unit used to express ratios of power or field quantities, particularly in telecommunications...
• NephanalysisThe process of creating a graphical depiction of cloud distribution and characteristics as observed from...
• NephcurveA line drawn on a nephanalysis chart that bounds part of a cloud system, such as the edge of a cloud shield...
• NephelometerAn instrument designed to measure the concentration of suspended particulate matter in a fluid, such as air...
• NephelometryA technique for measuring the concentration of suspended particles in a fluid by quantifying the amount of...
• NepheloscopeAn apparatus devised by James Espy in the 1830s to study how clouds form, in which air in a vessel is...
• NephologyThe scientific study of clouds, encompassing their formation, classification, physical properties, and their...
• NephometerAn instrument for measuring cloudiness, meaning the fraction of the sky covered by cloud, as distinct from a...
• NephoscopeAn instrument used to observe the direction and speed of cloud movement. Early versions, such as the comb...
• NERNNortheastern
• NESDISNational Environmental Satellite, Data, and Information Service. NESDIS collects, processes, stores...
• Nested gridsA computational technique used in numerical weather prediction and climate models where a higher-resolution...
• Net all-wave radiationThe net or resultant value of the upward and downward longwave and shortwave radiative fluxes through a plane...
• Net balanceThe overall change in the mass of a glacier over a specified period, representing the difference between...
• Net primary productionThe amount of organic matter produced by photosynthetic organisms in an ecosystem, minus the amount consumed...
• Net pyranometerAn instrument designed to measure the net shortwave radiation, which is the difference between incoming and...
• Net pyrgeometerA specialized radiometer that measures the net longwave radiation flux, which is the difference between the...
• Net pyrradiometerAn instrument designed to measure the net all-wave radiation, which is the algebraic sum of incoming and...
• Net radiationThe total balance of incoming and outgoing radiation at a surface, encompassing both shortwave (solar) and...
• Net radiometerAn instrument that measures the net radiation balance, representing the difference between all incoming and...
• Net rainfallIn hydrologic terms, the portion of rainfall which reaches a stream channel or the concentration point as...
• Net solar radiationThe difference between the solar radiation reaching a surface and the part reflected from it, which equals...
• Net terrestrial radiationThe difference between the outgoing longwave radiation emitted by the Earth's surface and atmosphere and the...
• NetworkA collection of interconnected observing stations or sensors designed to collect meteorological or...
• Network densityA measure of the spatial distribution and proximity of observation stations within a meteorological or...
• Neural networkA computational model inspired by the structure and function of biological neural systems, used in...
• NeutercaneA hybrid low-pressure system exhibiting characteristics of both tropical and extratropical cyclones. These...
• Neutral atmosphereAn atmospheric state where a parcel of air, if displaced vertically, experiences no net buoyant force and...
• Neutral equilibriumA state of atmospheric stability where a parcel of air, when displaced vertically, experiences no net buoyant...
• Neutral lineThe line that separates longitudinal magnetic fields of opposite polarity.
• Neutral modeA normal-mode solution of a linearized stability problem that neither grows nor decays, so its frequency is...
• Neutral stabilityAn atmospheric condition that exists in unsaturated air when the environmental lapse rate equals the dry...
• Neutral surfacesSurfaces in the ocean or atmosphere along which a fluid parcel can move without experiencing any buoyancy...
• NeutronA subatomic particle found in the nucleus of an atom, possessing no net electric charge. It contributes to...
• Neutron-scattering methodA technique used to measure soil moisture content by detecting the scattering and moderation of fast neutrons...
• NeutrosphereThe atmospheric layer extending from the Earth's surface up to the base of the ionosphere, characterized by a...
• NevadaA cold local wind that descends from the glaciers and snowfields of the Andes into the valleys and plains of...
• NévéA type of granular snow that has been partially compacted and recrystallized, representing an intermediate...
• New Guinea Coastal CurrentA western boundary current that flows northwestward along the north coast of New Guinea, carrying water of...
• New Guinea Coastal UndercurrentA subsurface western boundary current that flows northwestward along the north coast of New Guinea beneath...
• New snowFreshly fallen snow that has not yet undergone substantial metamorphism or compaction since its deposition...
• NEWDNortheastward
• NewtonThe standard unit of force in the International System of Units (SI), defined as the force required to...
• Newtonian fluidA fluid whose viscosity remains constant regardless of the shear rate applied to it. The shear stress within...
• Newtonian friction lawA simplified model for frictional forces in fluids, stating that the frictional stress is directly...
• Newtonian mechanicsThe branch of classical mechanics based on Newton's laws of motion, describing the motion of objects under...
• Newton's law of coolingA principle stating that the rate of heat loss from a body is directly proportional to the temperature...
• Newton's laws of motionA set of three fundamental physical laws that describe the relationship between a body and the forces acting...
• NEXRADNext Generation Weather Radar, a network of Doppler weather radars operated by the National Weather Service...
• NGMThe Nested Grid Model, a 48-hour numerical model of the atmosphere run twice daily by NCEP.
• NGTNight
• NHCNational Hurricane Center - one of three branches of the Tropical Prediction Center (TPC). This center...
• NHOP(National Hurricane Operations Plan) - The NHOP is issued annually by the Federal Coordinator for...
• Nieve penitenteA spike or pillar of compacted snow, firn or glacier ice, caused by differential melting and evaporation. The...
• NightThe period of the day between dusk and dawn.
• Night visual rangeThe maximum distance at which a moderately intense light source can be seen and identified by an observer at...
• Night windLocal wind patterns that develop or become more pronounced during the nighttime hours, often due to...
• NilasA type of very thin, elastic sea ice, typically dark in color, that forms on a calm sea surface. It is...
• NimbostratusA low-level, diffuse, and dark gray cloud layer that produces continuous precipitation, either rain or snow...
• NimbusA series of NASA meteorological research satellites launched between 1964 and 1978, designed to test advanced...
• Nipher shieldA flared, bell-shaped metal windshield set around the orifice of a precipitation gauge, devised by Francis...
• NitrateA polyatomic anion composed of one nitrogen atom and three oxygen atoms, carrying a negative charge. It forms...
• Nitrate ionA polyatomic anion with the chemical formula NO3-, consisting of one nitrogen atom covalently bonded to three...
• Nitrate radicalA highly reactive molecule consisting of one nitrogen atom and three oxygen atoms, with an unpaired electron...
• Nitric acidA strong inorganic acid with the chemical formula HNO3, existing as a colorless liquid or gas in the...
• Nitric acid trihydrateA crystalline compound with the chemical formula HNO3·3H2O, formed at very low temperatures in the polar...
• Nitric oxideA colorless gas composed of one nitrogen atom and one oxygen atom, with the chemical formula NO. It is...
• NitrificationA two-step biological process where ammonia is oxidized to nitrite and then to nitrate by specific...
• NitrogenA colorless, odorless, and tasteless diatomic gas, N2, that constitutes approximately 78% of Earth's...
• Nitrogen cycleThe biogeochemical cycle describing the transformation and movement of nitrogen between the atmosphere...
• Nitrogen dioxideA reddish-brown gas with the chemical formula NO2, characterized by a pungent, acrid odor. It is a major air...
• Nitrogen fixationThe process by which atmospheric nitrogen (N2) is converted into ammonia (NH3) or other nitrogen compounds...
• Nitrogen oxidesA group of highly reactive gases containing nitrogen and oxygen atoms, primarily nitric oxide (NO) and...
• Nitrogen-fixing plantsPlants that have a symbiotic relationship with nitrogen-fixing bacteria, typically residing in root nodules...
• Nitrous acidA weak inorganic acid with the chemical formula HNO2, which is unstable and exists primarily in solution or...
• Nitrous oxideA potent greenhouse gas with the chemical formula N2O, naturally produced by bacterial processes in soil and...
• NivalDescribing conditions or phenomena related to snow. This includes environments dominated by snow cover...
• NLYNortherly
• NMNautical Miles
• NMBRNumber
• NMCNational Meteorological Center
• NMLNormal
• NMRSNumerous
• NOAAThe National Oceanic and Atmospheric Administration, a scientific agency within the United States Department...
• NOAA space weather scalesA set of three scales developed by the National Oceanic and Atmospheric Administration to communicate the...
• NOAA Weather Radio"The voice of the National Weather Service" - NOAA Weather Radio broadcasts National Weather Service...
• NOAA Weather WireMass dissemination via satellite of National Weather Service products to the media and public.
• Noble gasesA group of chemical elements in Group 18 of the periodic table, characterized by their extreme chemical...
• Noctilucent cloudsWavy, silvery-blue clouds that form in the mesosphere, typically at altitudes between 76 and 85 kilometers...
• NocturnalRelated to nighttime; occurring at night.
• Nocturnal boundary layerA stable layer of air that forms near the Earth's surface after sunset, characterized by a temperature...
• Nocturnal coolingThe process by which the Earth's surface and the air directly above it lose heat to space through longwave...
• Nocturnal inversionUsed interchangably with Radiational Inversion; a temperature inversion that develops during the night as a...
• Nocturnal jetA low-level atmospheric jet stream that develops during the night within the nocturnal boundary layer. It is...
• Nocturnal minimum temperatureThe lowest air temperature recorded during a 24-hour period, typically occurring just after sunrise, when...
• Nocturnal thunderstormsThunderstorms which develop after sunset. They are often associated with the strengthening of the low level...
• NodeA point or region in a standing wave where the amplitude of oscillation is consistently zero or minimal. In...
• NOGAPSNavy Operational Global Atmospheric Prediction System; a 144-hour numerical model of the atmosphere run by...
• NOHRSCIn hydrologic terms, the National Operational Hydrologic Remote Sensing Center. An organization under the...
• NoiseAny unwanted signal or disturbance that interferes with the accurate measurement or interpretation of...
• Noise figureA measure of the degradation of the signal-to-noise ratio caused by components in a radio frequency signal...
• Noise filteringThe process of removing unwanted random fluctuations or disturbances from a signal or dataset, often to...
• Noise levelThe magnitude of unwanted random fluctuations or disturbances present in a signal or measurement, often...
• Noise powerThe total power of unwanted random signals that interfere with the detection or measurement of a desired...
• Noise temperatureA measure of the noise power available from a resistive load or an antenna, expressed as the temperature of...
• Noise thresholdThe minimum power or intensity level that a signal must exceed to be distinguished from background noise by a...
• NomogramA graphical calculating device that allows for the approximate computation of a function by reading values...
• Nonattainment areaAn area that does not meet ambient air quality standards.
• Noncoherent echoA radar return signal where the phase relationship between successive pulses is random or uncorrelated...
• Noncoherent targetA radar target composed of many individual scatterers whose relative positions change significantly between...
• NondeterministicDescribing a system or process whose future state cannot be precisely predicted from its current state, even...
• Nondimensional equationAn equation in which all variables and parameters have been scaled by characteristic quantities, resulting in...
• Nondimensional numberA quantity without any physical units, created by combining physical variables in such a way that all units...
• Nondimensional parameterA dimensionless quantity that characterizes a physical system or process, often arising from the...
• Nondispersive infrared spectrometryA technique used to measure the concentration of specific gases by detecting their absorption of infrared...
• Nonharmonic tidal analysisA method for analyzing tidal records that does not rely on the assumption that tides are composed of a fixed...
• Nonhydrostatic modelA numerical weather prediction model that does not assume hydrostatic balance, meaning it explicitly...
• Noninductive charging mechanismA process by which electric charge separation occurs within a cloud without the need for an external electric...
• NonlinearDescribing a system or process where the output is not directly proportional to the input, or where the...
• Nonlinear instabilityInstability in which a disturbance of sufficient finite amplitude grows even though the system is stable to...
• Nonlinearity of the equation of stateThe property of the equation of state for a fluid, such as air or seawater, where density is not a simple...
• Nonlocal closureA method used in atmospheric models to parameterize turbulent fluxes, where the flux at a given point depends...
• Nonlocal fluxThe transport of a quantity, such as heat, momentum, or moisture, by turbulent eddies that originate far from...
• Nonlocal mixingThe transport of atmospheric properties, such as heat, moisture, or momentum, over distances larger than the...
• Nonlocal static stabilityAn assessment of atmospheric stability that considers a finite vertical displacement of an air parcel, rather...
• Nonmethane hydrocarbonsA class of volatile organic compounds that are hydrocarbons, excluding methane. These compounds, abbreviated...
• Nonrecording rain gaugeAn instrument designed to collect and measure the total amount of precipitation over a specific period...
• Nonsupercell tornadoA tornado that develops from a parent thunderstorm that does not contain a deep, persistent, rotating updraft...
• Non-uniform sky conditionA localized sky condition which varies from that reported in the body of the report.
• Non-uniform visibilityA localized visibility which varies from that reported in the body of the report.
• Nonwetting liquidA liquid that does not spread across or adhere to a solid surface, instead forming distinct droplets with a...
• Nordenskjöld lineA line along which the mean temperature of the warmest month equals 9 minus one tenth of the mean temperature...
• Nor'easterA powerful extratropical cyclone that develops along the East Coast of North America, characterized by strong...
• NormalA statistical average or typical value of a meteorological variable, such as temperature or precipitation...
• Normal barometerA mercury barometer of a specific design and high precision, intended for use as a reference standard to...
• Normal chartA meteorological chart that displays the average values of a weather variable, such as temperature, pressure...
• Normal curve of errorA symmetrical, bell-shaped frequency distribution that represents the theoretical probability of a continuous...
• Normal distributionA continuous probability distribution that is symmetric about its mean, exhibiting a bell-shaped curve. It...
• Normal mode initializationA numerical procedure used to adjust the initial state of a numerical weather prediction model to remove...
• Normal modesThe fundamental oscillatory patterns or characteristic solutions of a linearized atmospheric or oceanic...
• Normal populationA statistical population whose values follow a normal distribution. In atmospheric science, this concept is...
• Normal stressesForces acting perpendicularly to a surface, either pushing (compression) or pulling (tension) on it. In fluid...
• Normal waterStandard seawater of accurately known chlorinity, prepared by the Hydrographical Laboratories in Copenhagen...
• Normal water surface elevationIn hydrologic terms, the lowest crest level of overflow on a reservoir with a fixed overflow level (spillway...
• Normal yearA year during which the precipitation or stream flow approximates the average for a long period of record.
• NormalizeTo scale data values to a standard range or distribution, often between 0 and 1 or with a mean of 0 and a...
• Normalized Difference Vegetation IndexA graphical indicator that quantifies vegetation health and density by analyzing the difference between...
• Normand's theoremA graphical relation on a skew-T log-p diagram or tephigram: the dry adiabat through the air temperature, the...
• NortadaA strong, persistent northerly wind that affects the western coast of the Iberian Peninsula, particularly...
• NorteA strong, cold northerly wind that affects Mexico and the Gulf of Mexico, particularly during the winter...
• North American Ensemble Forecast SystemAn atmospheric ensemble of 20 members each from the NCEP GEFS and CMC EPS ensemble systems.
• North American highA large, semi-permanent high-pressure system that develops over North America, particularly during the...
• North American Mesoscale Forecast SystemOne of the major weather models run by the National Centers for Environmental Prediction (NCEP) for producing...
• North Atlantic CurrentA powerful warm ocean current that extends the Gulf Stream northeastward across the North Atlantic Ocean. It...
• North Atlantic Deep WaterA large mass of cold, dense, and highly saline water that forms in the North Atlantic Ocean, primarily...
• North Atlantic Oscillation(Abbrev. NAO) - the NAO is a large-scale fluctuation in atmospheric pressure between the subtropical high...
• North Brazil CurrentA warm, westward-flowing ocean current that originates off the coast of northeastern Brazil, carrying water...
• North Equatorial CountercurrentAn eastward-flowing ocean current located between the westward-flowing North Equatorial Current and South...
• North Equatorial CurrentA broad, westward-flowing ocean current found in the tropical North Atlantic and North Pacific Oceans, driven...
• North foehnA warm, dry, and often gusty wind that descends the leeward side of a mountain range when moist air is forced...
• North Korea Cold CurrentA cold ocean current that flows southward along the eastern coast of the Korean Peninsula in the East Sea...
• North Pacific CurrentA broad, slow-moving ocean current that flows eastward across the North Pacific Ocean, forming the northern...
• North Pacific HighA semi-permanent, subtropical area of high pressure in the North Pacific Ocean. It is strongest in the...
• North WallThe northernmost boundary of the Gulf Stream, characterized by a sharp temperature gradient and strong...
• Northeast stormA large-scale extratropical cyclone that develops along the East Coast of North America and moves...
• Northeast tradesPersistent wind systems that blow from the northeast in the Northern Hemisphere's tropical and subtropical...
• NortheasterA cyclonic storm, also known as a nor'easter, affecting the northeastern coast of the United States and...
• NortherA strong, cold wind blowing from the north, particularly common in the southern United States and the Gulf of...
• Northern lightsA natural light display in the Earth's sky, predominantly seen in high-latitude regions, caused by the...
• NorthwesterA strong wind blowing from the northwest, often associated with the passage of a cold front or a...
• Norwegian CurrentA warm, salty ocean current that flows northeastward along the coast of Norway into the Barents Sea. It...
• Norwegian Sea Deep WaterA cold, dense water mass that forms in the Norwegian Sea through intense cooling and convection processes. It...
• Nor’west ArchA distinctive cloud formation that appears over the Canterbury Plains of New Zealand, characterized by a band...
• Nor'westerA strong, warm, and dry foehn wind that blows from the northwest across the Southern Alps of New Zealand...
• NOTAMAn alert issued through telecommunication systems to advise pilots of potential hazards or changes to...
• NotosThe ancient Greek mythological personification of the south wind, a name also applied to the wind itself...
• Nova ZemlyaAn atmospheric optical phenomenon observed in polar regions, where the sun appears to rise earlier or set...
• NowcastA very short-range weather forecast, typically covering a period from the present up to six hours into the...
• Noxon cliffA sharp poleward decrease in the stratospheric nitrogen dioxide column at winter high latitudes, found near...
• NRNear
• NRNNorthern
• NRWNarrow
• NSNimbostratus- A cloud of the class characterized by a formless layer that is almost uniformly dark gray; a...
• NSSFCNational Severe Storm Forecast Center
• NSSLNational Severe Storms Laboratory - this is one of NOAA's internationally known Environmental Research...
• nTThe abbreviation for nanotesla, a unit of magnetic flux density in the International System of Units (SI)...
• N.T.P.An abbreviation for Normal Temperature and Pressure, a set of standard conditions used for comparing gas...
• Nuclear winterA hypothetical scenario describing the severe and prolonged global climatic cooling that could follow a...
• NucleationThe initial process of forming a new thermodynamic phase, such as a liquid droplet from a vapor or an ice...
• NucleusA microscopic particle in the atmosphere that serves as a site for the condensation of water vapor or the...
• Nucleus counterAn instrument designed to measure the concentration of condensation nuclei or ice nuclei in the atmosphere...
• NudgingA data assimilation technique used in numerical weather prediction where model variables are continuously...
• Numerical dispersionAn artificial spreading or distortion of waves or features in a numerical model, caused by the discretization...
• Numerical forecastingThe process of predicting future states of the atmosphere and oceans by solving mathematical equations that...
• Numerical integrationA family of algorithms for calculating the approximate value of a definite integral. In numerical weather...
• Numerical modelingThe use of mathematical equations and computational algorithms to simulate physical processes and phenomena...
• Numerical simulationThe process of using computer programs to imitate the behavior of a real-world system or process over time...
• Numerical weather predictionSame as Numerical Forecasting; a computer forecast or prediction based on equations governing the motions and...
• NumerousA National Weather Service convective precipitation descriptor for a 60 or 70 percent chance of measurable...
• Nusselt numberA dimensionless number representing the ratio of convective to conductive heat transfer across a boundary. It...
• NVANegative Vorticity Advection - the advection of lower values of vorticity into an area.
• NWNorthwest
• NWDNorthward
• NWLYNorthwesterly
• NWPNumerical Weather Prediction, which is the application of mathematical models of the atmosphere and oceans to...
• NWRNOAA Weather Radio - "the voice of the National Weather Service" - NOAA Weather Radio broadcasts National...
• NWRDNorthwestward
• NWRNNorthwestern
• NWSNational Weather Service. An agency of the Federal Government within the Department of Commerce, National...
• NWSHNational Weather Service Headquarters
• NWSONational Weather Service Office
• NXTNext
• Nyquist frequencyThe maximum frequency that can be unambiguously resolved in a discretely sampled signal. It is equal to half...

294 of 10,756 terms in Meteorology and atmospheric science terminology (MLC-0110). Request the full dataset.