Weather — page 12 of 38

3,760 terms including subtopics (3,094 terms filed directly here)

Subtopics

Weather terms

  1. Entrainment The incorporation of fish, eggs, larvae, and other plankton with intake water flow entering and passing through a cooling water intake structure and into…
  2. Entrainment Zone A shallow region at the top of a convective boundary layer where fluid is entrained into the growing boundary layer from the overlying fluid by the…
  3. Entrance Region The region upstream from a wind speed maximum in a jet stream (jet max), in which air is approaching (entering) the region of maximum winds, and therefore…
  4. Entropy A measure of the unavailable or unusable energy in a system; energy that cannot be converted to another form.
  5. Environment All the natural and living things around us. The earth, air, weather, plants, and animals all make up our environment.
  6. Environment Canada The Canadian federal government department responsible for issuing weather forecasts and weather warnings in Canada.
  7. Environmental Lapse Rate The rate of decrease of air temperature with height, usually measured with a radiosonde.
  8. Environmental Temperature Sounding An instantaneous or near-instantaneous sounding of temperature as a function of height.
  9. EPA See Environmental Protection Agency.
  10. EPCTG Expecting
  11. EPV Equivalent Potential Vorticity
  12. Equi-Potential Line A line, in a field of flow, such that the total head is the same for all points on the line, and therefore the direction of flow is perpendicular to the…
  13. Equilibrium Drawdown The ultimate, constant drawdown for a steady rate of pumped discharge.
  14. Equilibrium Level (EL) - On a sounding, the level above the level of free convection (LFC) at which the temperature of a rising air parcel again equals the temperature of…
  15. Equilibrium Surface Discharge The steady rate of surface discharge which results from a long-continued, steady rate of net rainfall, with discharge rate equal to net rainfall rate.
  16. Equilibrium Time The time when flow conditions become substantially equal to those corresponding to equilibrium discharge or equilibrium drawdown.
  17. equilibrium vapor pressure The necessary vapor pressure around liquid water that allows the water to remain in equilibrium with its environment.
  18. Equinox The two times of the year when the sun crosses the equator and night and day are of equal length; usually occurs on March 21st (spring equinox) and…
  19. Equivalent Potential Temperature The equivalent potential temperature is the temperature a parcel at a specific pressure level and temperature would have if it were raised to 0 mb…
  20. ERLY Early
  21. ERN Eastern
  22. Erosion The wearing away of land surface by wind or water, intensified by land-clearing practices related to farming, residential or industrial development, road…
  23. error Error The difference between a measured value of a quantity and its true value. Different types of errors are inherent to observations.
  24. Eruptive In solar-terrestrial terms, solar activity levels with at least one radio event (10 cm) and several chromospheric events per day (Class C Flares).
  25. Eruptive Prominence on Limb (EPL) In solar-terrestrial terms, a solar prominence that becomes activa- ted and is seen to ascend from the sun.
  26. ESP Extended Streamflow Prediction
  27. EST See: expressed sequence tag.
  28. Estuary A water body where salt and fresh water meet resulting in brackish water. These areas usually have associated marshlands and are critical nursery and…
  29. Esturine waters Deepwater tidal habitats and tidal wetlands that are usually enclosed by land but have access to the ocean and are at least occasionally diluted by…
  30. Esturine Zone The area near the coastline that consists of estuaries and coastal saltwater wetlands.
  31. ETA 1. The Eta Model, now referred to as North Amercian Meso (NAM) an 84-hour numerical model of the atmosphere run four times daily by NCEP.
  32. Eta Model Now referred to as North Amercian Meso (NAM) is one of the operational numerical forecast models run at NCEP.
  33. Ethanol (C 2 5OH)Otherwise known as ethyl alcohol, alcohol, or grain spirit. A clear, colorless, flammable oxygenated hydrocarbon with a boiling point of 78.
  34. Evaporation The conversion of a liquid to a vapor (gas), usually by means of heat.
  35. Evaporation Pan A pan used to hold water during observations for the determination of the quantity of evaporation at a given location.
  36. Evaporation Rate In hydrologic terms, the quantity of water, expressed in terms of depth of liquid water, which is evaporated from a given surface per unit of time.
  37. Evaporation-mixing Fog Fog that forms when the evaporation of water raises the dew point of the adjacent air.
  38. Evaporimeter An instrument which measures the evaporation rate of water into the atmosphere.
  39. Evapotranspiration The net water loss (in vapour form) per unit area of land, both directly from the land surface, and indirectly through transpiring leaves.
  40. EVE Evening
  41. EWD Eastward
  42. EWW Extreme Wind Warning (EWW) inform the public of the need to take immediate shelter in an interior portion of a well-built structure due to the onset of…
  43. Excess Rain Effective rainfall in excess of infiltration capacity.
  44. Excessive Heat Excessive heat occurs from a combination of high temperatures (significantly above normal) and high humidities.
  45. Excessive Heat Outlook This CPC product, a combination of temperature and humidity over a certain number of days, is designed to provide an indication of areas of the country…
  46. Excessive Heat Warning Issued within 12 hours of the onset of the following criteria: heat index of at least 105F for more than 3 hours per day for 2 consecutive days, or heat…
  47. Excessive Heat Watch Issued by the National Weather Service when heat indices in excess of 105F (41C) during the day combined with nighttime low temperatures of 80F (27C) or…
  48. EXCLD Exclude
  49. Exclusive Flood Control Storage Capacity The space in a reservoir reserved for the sole purpose of regulating flood inflows to abate flood damage.
  50. Exit Region The region downstream from a wind speed maximum in a jet stream (jet max), in which air is moving away from the region of maximum winds, and therefore is…
  51. Exosphere The upper most layer of the earth's atmosphere; the only layer where atmospheric gases can escape into outer space.
  52. Experimental Product An experimental product is in the final stages of testing and evaluation. If the product proves accurate and valuable to users then the next step is to…
  53. Explosive Deepening A decrease in the minimum sea-level pressure of a tropical cyclone of 2.5 mb/hr for at least 12 hours or 5 mb/hr for at least six hours.
  54. Exponential growth Growth in which some quantity, such as population size, increases by a constant percentage of the whole during each year or other time period; when the…
  55. EXTD Extend/Extended
  56. Extended Forecast Discussion This discussion is issued once a day around 2 PM EST (3 PM EDT) and is primarily intended to provide insight into guidance forecasts for the 3- to 5-day…
  57. external data Data whose origin is not from within the ARM Program; may include data observed at ARM facilities, but whose processing and quality control is done by…
  58. External Data Center (XDC) (XDC) Stores data from non-ARM sources. It is managed by Brookhaven National Laboratory.
  59. external instruments Instruments that belong to organizations that are outside of the ARM Program.
  60. Extraterrestrial Radiation The theoretically-calculated radiation flux from the sun at the top of the atmosphere, before losses by atmospheric absorption.
  61. Extratropical A term used in advisories and tropical summaries to indicate that a cyclone has lost its "tropical" characteristics.
  62. Extratropical Cyclone A cyclone in the middle and high latitudes often being 2000 kilometers in diameter and usually containing a cold front that extends toward the equator for…
  63. Extratropical Low A low pressure center which refers to a migratory frontal cyclone of middle and higher latitudes.
  64. extreme event time The time of extreme meteorological events such as min/max temperature and wind gusts.
  65. Extreme Ultraviolet (EUV) A portion of the electromagnetic spectrum from approximately 100 to 1000 angstroms.
  66. Extreme Wind Warning Extreme Wind Warning (EWW) inform the public of the need to take immediate shelter in an interior portion of a well-built structure due to the onset of…
  67. Extremely Low Frequency (ELF) (ELF) Refers to a band of frequencies from 30 to 300 Hz.
  68. EXTRM Extreme
  69. EXTSV Extensive
  70. Eye The relatively calm center in a hurricane that is more than one half surrounded by wall cloud.
  71. Eye Wall It is an organized band of cumuliform clouds that immediately surrounds the center (eye) of a hurricane.
  72. Eyewall / Wall Cloud An organized band or ring of cumulonimbus clouds that surround the eye, or light-wind center of a tropical cyclone.
  73. F 1) Fahrenheit- The standard scale used to measure temperature in the United States.
  74. F Corona In solar-terrestrial terms, of the white-light corona (that is, the corona seen by the eye at a total solar eclipse), that portion which is caused by…
  75. F Region In solar-terrestrial terms, the upper layer of the ionosphere, approximately 120 to 1500 km in altitude.
  76. F Scale Abbreviation for Fujita Scale, a system of rating the intensity of tornadoes; for detailed information, see the definition for that term.
  77. FA Forecast Area
  78. FAA Federal Aviation Administration
  79. Face Exposed surface of dam materials (earth, rockfill, or concrete), upstream and downstream. The external surface which limits the structure, see neatlines.
  80. Facula In solar-terrestrial terms, a bright region of the photosphere seen in white light, seldom visible except near the solar limb.
  81. Fahrenheit (abbrev. F) The standard scale used to measure temperature in the United States.
  82. Fair It is usually used at night to describe less than 3/8 opaque clouds, no precipitation, no extremes of visibility, temperature or winds.
  83. Fall The amount of slope given to horizontal runs of pipe.
  84. Fall Line Direction that water flows down a hill.
  85. fall streaks The falling ice crystals that evaporate before reaching the ground.
  86. Fall Wind A strong, cold, downslope wind.
  87. Fallstreak Same as Virga; streaks or wisps of precipitation falling from a cloud but evaporating before reaching the ground.
  88. Fan An electrically or mechanically driven device that is used to pull air through the radiator or oil cooler.
  89. Fanning A pattern of plume dispersion in a stable atmosphere, in which the plume fans out in the horizontal and meanders about at a fixed height.
  90. FASTST Fastest
  91. Fathom Unit of water depth equal to 6 feet.
  92. FAWS Flight Advisory Weather Service
  93. FBO (Great Lakes Freeze-Up/Break-Up Outlook) - A National Weather Service product to keep mariners informed of the projected freeze-up date or break-up date…
  94. FCST NWSRFS Forecast Program to produce operational forecasts.
  95. Federal Snow Sampler A snow sampler consisting of five or more sections of sampling tubes, one which has a steel cutter on the end.
  96. feedback the process by which an initial change brings about additional change that either reinforces or counteracts the initial change.
  97. Feedback Mechanisms Factors which increase or amplify (positive feedback) or decrease (negative feedback) the rate of a process.
  98. Feeder Bands Lines or bands of low-level clouds that move (feed) into the updraft region of a thunderstorm, usually from the east through south (i.e.
  99. Feedlot Confined outdoor or indoor space used to raise hundreds to thousands of domesticated livestock. See rangeland.
  100. FEMA - Federal Emergency Management Agency.

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