Weather terms starting with C

325 terms

  1. Civil Dusk The time at which the sun is 6 degrees below the horizon in the evening. At this time objects are distinguishable but there is no longer enough light to…
  2. Civil Emergency Message (Abbrev. CEM) - A message issued by the National Weather Service in coordination with Federal, state or local government to warn the general public of a…
  3. CL An abbreviation used on climate outlook maps issued by CPC to indicate areas where equal chances of experiencing below-normal, normal, and above-normal…
  4. Class I Areas Geographic areas designated by the Clean Air Act where only a small amount or increment of air quality deterioration is permissible.
  5. CLD Cloud- A visible aggregate of minute water droplets or ice particles in the atmosphere above the Earth's surface.
  6. Clear Air Turbulence (CAT) - In aviation, sudden severe turbulence occurring in cloudless regions that causes violent buffeting of aircraft.
  7. Clear Ice A thin coating of ice on terrestrial objects, caused by rain that freezes on impact.
  8. Clear Slot With respect to severe thunderstorms, a local region of clearing skies or reduced cloud cover, indicating an intrusion of drier air; often seen as a…
  9. Clear_sky Clear sky Sky with a total cloud cover of less than one okta (or one-tenth in the United States).
  10. Client Agency As used in connection with reimbursable National Weather Service (NWS) fire weather services, a public fire service or wildlands management agency…
  11. Climate The prevailing or average weather conditions of a geographic region.
  12. Climate Change A term used to describe short and long-term affects on the Earth's climate as a result of human activities such as fossil fuel combustion and vegetation…
  13. Climate Diagnostics Bulletin (CDB) - The monthly CPC Bulletin reports on the previous months' status of the ocean-atmosphere climate system and provides various seasonal ENSO-related…
  14. Climate Diagnostics Center (CDC) - The mission of NOAA's Climate Diagnostics Center is to identify the nature and causes for climate variations on time scales ranging from a month…
  15. Climate Feedback An interaction mechanism between processes in the climate system is called a climate feedback, when the result of an initial process triggers changes in a…
  16. Climate Lag The delay that occurs in climate change as a result of some factor that changes only very slowly.
  17. Climate Model Mathematical model for quantitatively describing, simulating, and analyzing the interactions between the atmosphere and underlying surface (e.g.
  18. Climate modeling The simulation of the climate using computer-based models. See climate model, General Circulation Model.
  19. Climate Outlook A climate outlook issued by the CPC gives probabilities that conditions, averaged over a specified period, will be below-normal, normal, or above-normal.
  20. Climate Prediction Center This Center is one of several centers under the National Centers for Environmental Prediction (NCEP) part of the National Weather Service (NWS) in the…
  21. Climate Sensitivity In IPCC Reports, equilibrium climate sensitivity refers to the equilibrium change in global mean surface temperature following a doubling of the…
  22. Climate System The system consisting of the atmosphere (gases), hydrosphere (water), lithosphere (solid rocky part of the Earth), and biosphere (living) that determine…
  23. Climate System (or Earth System) The five physical components (atmosphere, hydrosphere, cryosphere, lithosphere, and biosphere) that are responsible for the climate and its variations.
  24. Climate variability Climate (climatic) variability 1)In the most general sense, the term "climate variability" denotes the inherent characteristic of climate which manifests…
  25. Climatological atlas Climatological atlas Atlas composed mainly of climatological charts. It represents especially the monthly and annual distributions of the principal…
  26. Climatological Outlook An outlook based upon climatological statistics for a region, abbreviated as CL on seasonal outlook maps.
  27. Climatology The science that deals with the phenomena of climates or climatic conditions.
  28. CLIMO Climatology/Climatological
  29. Climometer An instrument that measures angles of inclination; used to measure cloud ceiling heights.
  30. Closed Basin A basin draining to some depression or a pond within its area, from which water is lost only by evaporation or percolation.
  31. Closed Basin Lake Flooding Flooding that occurs on lakes with either no outlet or a relatively small one. Seasonal increases in rainfall cause the lake level to rise faster than it…
  32. Closed Low A low pressure area with a distinct center of cyclonic circulation which can be completely encircled by one or more isobars or height contour lines.
  33. Cloud A claim to the title of a property that, if valid, would prevent a purchaser from obtaining a clear title.
  34. Cloud amount Cloud amount (cover) That portion of the sky cover which is attributed to clouds.
  35. cloud base The lowest portion of a cloud.
  36. cloud base height For a given cloud or cloud layer, the lowest level of the atmosphere where cloud properties are detectable.
  37. Cloud Ceiling Same as Ceiling; the height of the cloud base for the lowest broken or overcast cloud layer.
  38. Cloud Condensation Nuclei Small particles in the air on which water vapor condenses and forms cloud droplets.
  39. cloud condensation nucleus A particle, either liquid or solid, upon which water condenses to form cloud droplets.
  40. cloud cover The amount of the sky obscured by clouds when observed at a particular location.
  41. cloud deck The top of a cloud layer, usually viewed from an aircraft.
  42. cloud fraction Fraction of sky covered by clouds, observed directly or derived from SW irradiance.
  43. cloud ice water The concentration (mass/vol) of ice water particles in a cloud.
  44. Cloud Layer An array of clouds whose bases are at approximately the same level.
  45. cloud liquid water The concentration (mass/vol) of liquid water droplets in a cloud.
  46. Cloud Movement The direction toward which a cloud is moving
  47. Cloud Streets Rows of cumulus or cumulus-type clouds aligned parallel to the low-level flow. Cloud streets sometimes can be seen from the ground, but are seen best on…
  48. Cloud Tags Ragged, detached cloud fragments; fractus or scud.
  49. cloud top height For a given cloud or cloud layer, the highest level of the atmosphere where cloud properties are detectable.
  50. Cloudy When 7/8ths or more of the sky is covered by clouds.
  51. CLR Clear
  52. CLRG Clearing
  53. Clutter Radar echoes that interfere with observation of desired signals on the radar display.
  54. CM Abbreviation for centiMorgan.
  55. CMPLT Complete
  56. CMPLX Complex
  57. CNIF In hydrologic terms, Calibration Network Information Files.
  58. CNTR Center
  59. CNTRL Central
  60. CNVG Converge
  61. CNVTV Convective
  62. Co-Benefit The benefits of policies that are implemented for various reasons at the same time – including climate change mitigation – acknowledging that most…
  63. Co-control benefit The additional benefit derived from an environmental policy that is designed to control one type of pollution, while reducing the emissions of other…
  64. Coal A black or brownish black solid, combustible substance formed by the partial decomposition of vegetable matter without access to air.
  65. Coal coke A hard, porous product made from baking bituminous coal in ovens at temperatures as high as 2,000 degrees Fahrenheit.
  66. Coal gasification Conversion of solid coal to synthetic natural gas (SNG) or a gaseous mixture that can be burned as a fuel.
  67. Coal liquefaction Conversion of solid coal to a liquid fuel such as synthetic crude oil or methanol.
  68. Coal Mine Methane Coal mine methane is the subset of CBM that is released from the coal seams during the process of coal mining.
  69. Coalbed methane A methane-rich gas, similar to natural gas, produced from in-situ coal through drilled wells that are typically completed open-hole, as opposed to the…
  70. Coalescence The process by which water droplets in a cloud collide and come together to form raindrops.
  71. Coastal Waters In the Great Lakes region, the waters within the territorial jurisdiction of the United States consisting of the Great Lakes, their connecting waters…
  72. Coastal Waters Forecast (CWF) The marine forecast for areas, including bays, harbors, and sounds, from a line approximating the mean high water mark (average height of high water over…
  73. Coastal/Lakeshore Flood Advisory Minor flooding is possible (i.e., over and above normal high tide levels. Coastal/Lakeshore Flood Advisories are issued using the Coastal/Lakeshore Hazard…
  74. Coastal/Lakeshore Flood Warning Flooding that will pose a serious threat to life and property is occurring, imminent or highly likely.
  75. Coastal/Lakeshore Flood Watch Flooding with significant impacts is possible. Coastal/Lakeshore Flood Watches are issued using the Coastal/Lakeshore Hazard Message (CFW) product.
  76. Coastal/Lakeshore Flooding (i) (Oceanic) Coastal Flooding is the inundation of land areas adjacent to bodies of salt water connected to the Atlantic Ocean, Pacific Ocean, or Gulf of…
  77. COE In hydrologic terms, Corps of Engineers.
  78. Cogeneration The generation of electricity or shaft power by an energy conversion system and the concurrent use of rejected thermal energy from the conversion system…
  79. Coherent Radar A radar that utilizes both signal phase and amplitude to determine target characteristics.
  80. Cold Advection Transport of cold air into a region by horizontal winds.
  81. Cold Air Avalanche Downslope flow pulsations that occur at more or less regular intervals as cold air builds up on a peak or plateau, reaches a critical mass, and then…
  82. Cold Air Dam A shallow cold air mass which is carried up the slope of a mountain barrier, but with insufficient strength to surmount the barrier.
  83. Cold Air Damming (CAD) The phenomenon in which a low-level cold air mass is trapped topographically. Often, this cold air is entrenched on the east side of mountainous terrain.
  84. Cold Air Funnel A funnel cloud or (rarely) a small, relatively weak tornado that can develop from a small shower or thunderstorm when the air aloft is unusually cold…
  85. cold front A weather condition accompanied by high, clear skies, and a sudden drop in temperature.
  86. Cold low Cold low (or cold cyclone) At a given level in the atmosphere, any low that is generally characterized by colder air near its center than around its…
  87. Cold Occlusion A frontal zone formed when a cold front overtakes a warm front and, being colder than the air ahead of the warm front, slides under the warm front…
  88. Cold Pool A region of relatively cold air, represented on a weather map analysis as a relative minimum in temperature surrounded by closed isotherms.
  89. collaborating program A program joining with the ARM Program to pursue a specific set of objectives by providing resources and participating in active planning and execution of…
  90. Collar Cloud A generally circular ring of cloud that may be observed on rare occasions surrounding the upper part of a wall cloud.
  91. Collection Efficiency The fraction of droplets approaching a surface that actually deposit on that surface.
  92. Colorado Low A low pressure storm system that forms in winter in southeastern Colorado or northeastern New Mexico and tracks northeastward across the central plains of…
  93. Columnar Ice Ice consisting of columnar shaped grain. The ordinary black ice is usually columnar-grained.
  94. Combined Seas Combination of both wind waves and swell. Also called "Seas" and is approximately equal to significant wave height.
  95. Combustion The process of burning; the oxidation of a material by applying heat, which unites oxygen with a material or fuel.
  96. Comma Cloud A synoptic scale cloud pattern with a characteristic comma-like shape, often seen on satellite photographs associated with large and intense low-pressure…
  97. Comma Echo A thunderstorm radar echo which has a comma-like shape. It often appears during latter stages in the life cycle of a bow echo
  98. Commercial Sector Consists of businesses that are not engaged in transportation or manufacturing or other types of industrial activities.
  99. Complex Gale/Storm In the high seas and offshore forecasts, an area for which gale/storm force winds are forecast or are occurring but for which no single center is the…
  100. Complex Terrain Typically used to refer to mountainous terrain. In general usage, it may also refer to coastal regions and heterogeneous landscapes.