Subj : Wx Terms (C)(3) To : All From : Daryl Stout Date : Mon Sep 04 2017 12:06 am CI Cirrus clouds- High-level clouds (16,000 feet or higher), composed of ice crystals and appearing in the form of white, delicate filaments or white or mostly white patches or narrow bands. Cirrus clouds typically have a fibrous or hairlike appearance, and often are semi-transparent. Thunderstorm anvils are a form of cirrus cloud, but most cirrus clouds are not associated with thunderstorms. CIG Ceiling- The height of the lowest layer of clouds, when the sky is broken or overcast. CIN Convective INhibition. A measure of the amount of energy needed in order to initiate convection. Values of CIN typically reflect the strength of the cap. They are obtained on a sounding by computing the area enclosed between the environmental temperature profile and the path of a rising air parcel, over the layer within which the latter is cooler than the former. (This area sometimes is called negative area.) See CAPE. CIO Chief Information Officer Circulation The flow, or movement, of a fluid (e.g., water or air) in or through a g iven area or volume. Cirriform High altitude ice clouds with a very thin wispy appearance. Cirrocumulus A cirriform cloud characterized by thin, white patches, each of which is composed of very small granules or ripples. These clouds are of high altitude (20,000-40,000 ft or 6000 -12,000 m). Cirrostratus A cloud of a class characterized by a composition of ice crystals and often by the production of halo phenomena and appearing as a whitish and usually somewhat fibrous veil, often covering the whole sky and sometimes so thin as to be hardly discernible. These clouds are of high altitude (20,000-40,000 ft or 6000 -12,000 m). Cirrus (abbrev. CI) High-level clouds (16,000 feet or higher), composed of ice crystals and appearing in the form of white, delicate filaments or white or mostly white patches or narrow bands. Cirrus clouds typically have a fibrous or hairlike appearance, and often are semi-transparent. Thunderstorm anvils are a form of cirrus cloud, but most cirrus clouds are not associated with thunderstorms. Civil Dawn The time of morning at which the sun is 6ø below the horizon. At this time, there is enough light for objects to be distiguishable and that outdoor activities can commence. Civil Dusk The time at which the sun is 6ø below the horizon in the evening. At this time objects are distinguishable but there is no longer enough light to perform any outdoor activities. 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 non-weather related time-critical emergency which threatens life or property, e.g. nuclear accident, toxic chemical spill, etc. 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 conditions are possible. Class I Areas Geographic areas designated by the Clean Air Act where only a small amount or increment of air quality deterioration is permissible. CLD Cloud- A visible aggregate of minute water droplets or ice particles in the atmosphere above the Earth's surface. Clear Air Turbulence (CAT) - In aviation, sudden severe turbulence occurring in cloudless regions that causes violent buffeting of aircraft. Clear Ice A thin coating of ice on terrestrial objects, caused by rain that freezes on impact. The ice is relatively transparent, as opposed to rime ice, because of large drop size, rapid accretion of liquid water, or slow dissipation of latent heat of fusion. 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 bright area with higher cloud bases on the west or southwest side of a wall cloud. A clear slot is believed to be a visual indication of a rear flank downdraft. Client Agency As used in connection with reimbursable National Weather Service (NWS) fire weather services, a public fire service or wildlands management agency, Federal or non-Federal, which requires and uses NWS fire and forestry meteorological services. Climate The composite or generally prevailing weather conditions of a region, throughout the year, averaged over a series of years. Climate Change A non-random change in climate that is measured over several decades or longer. The change may be due to natural or human-induced causes. 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 outlooks. It is issued by the fifteenth of the month. 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 to centuries. Climate Model Mathematical model for quantitatively describing, simulating, and analyzing the interactions between the atmosphere and underlying surface (e.g., ocean, land, and ice). 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. 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 National Oceanic and Atmospheric Administration (NOAA). The Center serves the public by assessing and forecasting the impacts of short-term climate variability, emphasizing enhanced risks of weather-related extreme events, for use in mitigating losses and maximizing economic gains. Climate System The system consisting of the atmosphere (gases), hydrosphere (water), lithosphere (solid rocky part of the Earth), and biosphere (living) that determine the Earth's climate. Climatological Outlook An outlook based upon climatological statistics for a region, abbreviated as CL on seasonal outlook maps. CL indicates that the climate outlook has an equal chance of being above normal, normal, or below normal. Climatology The science that deals with the phenomena of climates or climatic conditions. CLIMO Climatology/Climatological Climometer An instrument that measures angles of inclination; used to measure cloud ceiling heights. Closed Basin A basin draining to some depression or pond within its area, from which water is lost only by evaporation or percolation. A basin without a surface outlet for precipitation falling precipitation. 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 can drain. The water may stay at flood stage for weeks, months, or years. 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. The term usually is used to distinguish a low pressure area aloft from a low-pressure trough. Closed lows aloft typically are partially or completely detached from the main westerly current, and thus move relatively slowly (see Cutoff Low). Cloud (abbrev. CLD) A visible aggregate of minute water droplets or ice particles in the atmosphere above the Earth's surface. Cloud Ceiling Same as Ceiling; the height of the cloud base for the lowest broken or overcast cloud layer. --- þ Synchronet þ The Thunderbolt BBS - wx1der.dyndns.org .