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  2. Anomalous propagation - Wikipedia

    en.wikipedia.org/wiki/Anomalous_propagation

    Anomalous propagation refers to false radar echoes usually observed when calm, stable atmospheric conditions, often associated with super refraction in a temperature inversion, direct the radar beam toward the ground. The processing program will then wrongly place the return echoes at the height and distance it would have been in normal conditions.

  3. Hail spike - Wikipedia

    en.wikipedia.org/wiki/Hail_spike

    The multiple reflections of the radar beam causing the hail spike. Generally known as hail spikes, these are the result of energy from the radar hitting hail, very heavy rain, or in extreme cases, debris being lofted by a tornado, and being reflected to the ground, where they reflect back to the hail and then to the radar as in the image on the left. [1]

  4. Engine knocking - Wikipedia

    en.wikipedia.org/wiki/Engine_knocking

    In spark-ignition internal combustion engines, knocking (also knock, detonation, spark knock, pinging or pinking) occurs when combustion of some of the air/fuel mixture in the cylinder does not result from propagation of the flame front ignited by the spark plug, but when one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front.

  5. Hook echo - Wikipedia

    en.wikipedia.org/wiki/Hook_echo

    A hook echo is a pendant or hook-shaped weather radar signature as part of some supercell thunderstorms. It is found in the lower portions of a storm as air and precipitation flow into a mesocyclone, resulting in a curved feature of reflectivity. The echo is produced by rain, hail, or debris being wrapped around the supercell. [1]

  6. Radar jamming and deception - Wikipedia

    en.wikipedia.org/wiki/Radar_jamming_and_deception

    Because the external radar causing the transponder to respond is generally not synchronised with your own radar (i.e. different pulse-repetition frequencies), these black dots appear randomly across the display and the operator sees through and around them. The returning image may be much larger than the "dot" or "hole", as it has become known ...

  7. Weather radar - Wikipedia

    en.wikipedia.org/wiki/Weather_radar

    Weather radar in Norman, Oklahoma with rainshaft Weather (WF44) radar dish University of Oklahoma OU-PRIME C-band, polarimetric, weather radar during construction. Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.).

  8. Scotland vs South Africa as it happened: Result and ... - AOL

    www.aol.com/news/scotland-vs-south-africa-live...

    Oh no - a first lineout misfire of the afternoon from Scotland at the worst possible moment, allowing South Africa to survive and clear. Two missed opportunities in the 22 - will they live to ...

  9. Category : Airliner accidents and incidents caused by weather

    en.wikipedia.org/wiki/Category:Airliner...

    Pages in category "Airliner accidents and incidents caused by weather" The following 126 pages are in this category, out of 126 total. This list may not reflect recent changes .