Subj : Wx Terms (C)(2) To : All From : Daryl Stout Date : Tue Jul 04 2017 12:04 am CCL Convective Condensation Level- The level in the atmosphere to which an air parcel, if heated from below, will rise dry adiabatically, without becoming colder than its environment just before the parcel becomes saturated. See Lifted Condensation Level (LCL). CD cold CDB Computing Development Branch (NCEP) CDC Climate Diagnostic Center, the mission of the Climate Diagnostics Center (CDC) is to advance national capabilities to interpret the causes of observed climate variations, and to apply this knowledge to improve climate models and forecasts and develop new climate products that better serve the needs of the public and decision-makers. CDD Cooling Degree Days- A form of degree day used to estimate energy requirements for air conditioning or refrigeration. Typically, cooling degree days are calculated as how much warmer the mean temperature at a location is than 65ø F on a given day. For example, if a location experiences a mean temperature of 75ø F on a certain day, there were 10 CDD (Cooling Degree Days) that day because 75 - 65 = 10. CDFNT Cold Front CDT Central Daylight Time Ceiling (Abbrev. CIG) - The height of the cloud base for the lowest broken or overcast cloud layer. Ceilometer A device using a laser or other light source to determine the height of a cloud base. An optical ceilometer uses triangulation to determine the height of a spot of light projected onto the base of the cloud; a laser ceilometer determines the height by measuring the time required for a pulse of light to be scattered back from the cloud base. Cell Convection in the form of a single updraft, downdraft, or updraft/downdraft couplet, typically seen as a vertical dome or tower as in a towering cumulus cloud. A typical thunderstorm consists of several cells. The term "cell" also is used to describe the radar echo returned by an individual shower or thunderstorm. Such usage, although common, is technically incorrect. Celsius The standard scale used to measure temperature in most areas outside the United States. On this scale, the freezing point of water is 0ø F and the boiling point is 100ø F. To convert a Fahrenheit temperature to Celsius, subtract 32 from it and then multiply by 5/9: øC = (øF - 32) * 5/9 CEM Civil Emergency Message. 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. Center Generally speaking, the vertical axis of a tropical cyclone, usually defined by the location of minimum wind or minimum pressure. The cyclone center position can vary with altitude. In advisory products, refers to the center position at the surface. Centimeter Burst A solar radio burst in the centimeter wavelength range. Central Meridian Passage (CMP) In solar-terrestrial terms, the passage of an Active Region or other feature across the longitude meridian that passes through the apparent center of the solar disk. CFC Chlorofluorocarbon CFP Cold Front Passage CFS In hydrologic terms, Cubic Feet per Second - the flow rate or discharge equal to one cubic foot (of water, usually) per second. This rate is equivalent to approximately 7.48 gallons per second. This is also referred to as a second-foot. Cfs-Day In hydrologic terms, the volume of water discharged in twenty four hours, with a flow of one cubic foot per second is widely used; 1 cfs-day is 24 x 60 x 60 = 86,000 cubic feet, 1.983471 acre-feet, or 646,317 gallons. The average flow in cubic feet per second for any time period is the volume of flow in cfs-days. CG Cloud-to-Ground Lightning Chance A National Weather Service precipitation descriptor for 30, 40, or 50 percent chance of measurable precipitation (0.01 inch). When the precipitation is convective in nature, the term scattered is used. See Precipitation Probability (PoP). Channel In hydrologic terms, also known as Watercourse; an open conduit either naturally or artificially created which periodically, or continuously contains moving water, or forms a connecting link between two bodies of water. River, creek, run, branch, anabranch, and tributary are some of the terms used to describe natural channels. Natural channels may be single or braided. Canal and floodway are some of the terms used to describe artificial channels. Channel Inflow In hydrologic terms, water, which at any instant, is flowing into the channel system form surface flow, subsurface flow, base flow, and rainfall that has directly fallen onto the channel. Channel Lead In hydrologic terms, an elongated opening in the ice cover caused by a water current. Channel Routing In hydrologic terms, the process of determining progressively timing and shape of the flood wave at successive points along a river. Channeled High Winds In mountainous areas or in cities with tall buildings, air may be channeled through constricted passages producing high winds. Santa Ana winds and winds through passes from the cold Alaskan interior to the sea are examples of these winds. Channeled high winds are local in nature but can be extremely strong. These winds generally occur in well-defined areas. Channelization In hydrologic terms, the modification of a natural river channel; may include deepening, widening, or straightening. CHC Chance Chemistry Model A computer model used in air pollution investigations that simulates chemical and photochemical reactions of the pollutants during their transport and diffusion. CHG Change CHGS changes Chinook This is a region-specific term used for Foehn Winds in the lee of the Rocky Mountains in the United States; Foehn Winds are warm, dry winds that occur in the lee of high mountain ranges. It is a fairly common wintertime phenomena in the mountainous west and in parts of Alaska. These winds develop in well-defined areas and can be quite strong. Chinook Arch A foehn cloud formation appearing as a bank of altostratus clouds east of the Rocky Mountains, heralding the approach of a chinook. It forms in the rising portion of standing waves on the lee side of the mountains. An observer underneath or east of the cloud sees an arch of clear air between the cloud's leading edge and the mountains below. The cloud appears to converge with the mountains to the north and south due to a perspective effect. Chlorofluorocarbons (CFCs) - Manufactured substances used as coolants and computer-chip cleaners. When these products break down they destroy stratospheric ozone, creating the Antarctic Ozone Hole in the Southern Hemisphere spring (Northern Hemisphere autumn). While no longer in use, their long lifetime will lead to a very slow removal from the atmosphere. Chromosphere In solar-terrestrial terms, the layer of the solar atmosphere above the photosphere and beneath the transition region and the corona. Chromospheric Events In solar-terrestrial terms, flares that are just Chromospheric Events without Centimetric Bursts or Ionospheric Effects. (SID) (Class C flare) --- þ Synchronet þ The Thunderbolt BBS - wx1der.dyndns.org .