Subj : Wx Terms (C)(4) To : All From : Daryl Stout Date : Mon Sep 04 2017 12:06 am Cloud Condensation Nuclei Small particles in the air on which water vapor condenses and forms cloud droplets. Cloud Layer An array of clouds whose bases are at approximately the same level. Cloud Movement The direction toward which a cloud is moving. 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 satellite photographs. Cloud Tags Ragged, detached cloud fragments; fractus or scud. CLR Clear CLRG Clearing Clutter Radar echoes that interfere with observation of desired signals on the radar display. CMPLT Complete CMPLX Complex CNIF In hydrologic terms, Calibration Network Information Files. CNTR Center CNTRL Central CNVG Converge CNVTV Convective Coalescence The process by which water droplets in a cloud collide and come together to form raindrops. Coastal Waters Includes the area from a line approximating the mean high water along the mainland or island as far out as 100 nautical miles including the bays, harbors and sounds. 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 a 19-year period) along the mainland or near shore islands extending out to as much as 100 NM. 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 Message (CFW) product. Coastal/Lakeshore Flood Warning Flooding that will pose a serious threat to life and property is occurring, imminent or highly likely. Coastal/Lakeshore Flood Warnings are issued using the Coastal/Lakeshore Hazard Message (CFW) product. Coastal/Lakeshore Flood Watch Flooding with significant impacts is possible. Coastal/Lakeshore Flood Watches are issued using the Coastal/Lakeshore Hazard Message (CFW) product. 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 Mexico, caused by sea waters over and above normal tidal action. This flooding may impact the immediate oceanfront, gulfs, bays, back bays, sounds, and tidal portions of river mouths and inland tidal waterways. (ii) Lakeshore Flooding is the inundation of land areas adjacent to one of the Great Lakes caused by lake water exceeding normal levels. Lakeshore flooding impacts the immediate lakefront, bays, and the interfaces of lakes and connecting waterways, such as rivers. COE In hydrologic terms, Corps of Engineers. Cold Advection Transport of cold air into a region by horizontal winds. 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 cascades down the slopes. 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. The cold air, trapped upwind of the barrier alters the effective terrain configuration of the barrier to larger-scale approaching flows. 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. Cold Air Damming often implies that the trapped cold air mass is influencing the dynamics of the overlying air mass, e.g. in an overrunning scenario. Effects on the weather may include cold temperatures, freezing precipitation, and extensive cloud cover. 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 (hence the name). They are much less violent than other types of tornadoes. Cold Front A zone separating two air masses, of which the cooler, denser mass is advancing and replacing the warmer. 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, lifting it aloft. Compare with warm occlusion. Cold Pool A region of relatively cold air, represented on a weather map analysis as a relative minimum in temperature surrounded by closed isotherms. Cold pools aloft represent regions of relatively low stability, while surface-based cold pools are regions of relatively stable air. Collar Cloud A generally circular ring of cloud that may be observed on rare occasions surrounding the upper part of a wall cloud. This term sometimes is used (incorrectly) as a synonym for wall cloud. Collection Efficiency The fraction of droplets approaching a surface that actually deposit on that surface. 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 the U.S. over a period of several days, producing blizzards and hazardous winter weather. Columnar Ice In hydrologic terms, ice consisting of columnar shaped grain. The ordinary black ice is usually columnar-grained. Combined Seas Combination of both wind waves and swell. Also called "Seas" and is approximately equal to significant wave height. 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 systems. 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. 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 principal generator of these winds. Complex Terrain Typically used to refer to mountainous terrain. In general usage, it may also refer to coastal regions and heterogeneous landscapes. Composite An average that is calculated according to specific criteria. For example, one might want a composite for the rainfall at a given location for all years where the temperature was much above average. Composite Hydrograph A stream discharge hydrograph which includes base flow, or one which corresponds to a net rain storm of duration longer than one unit period. --- þ Synchronet þ The Thunderbolt BBS - wx1der.dyndns.org .