Tormenta severa

Definition

Storms are generally classified as a meteorological hazard,  caused by short-lived, micro- to meso-scale extreme weather and atmospheric conditions that last from minutes to days (EM-DAT).

Facts and figures

There are several different types of storms distinguished by the strength and characteristics of atmospheric disturbances:

  • Convective/local storm: A type of meteorological hazard generated by the heating of air and the availability of moist and unstable air masses. Convective storms range from localized thunderstorms (with heavy rain and/or hail, lightning, high winds, tornadoes) to meso-scale, multi-day events.
  • Sandstorm, dust storm: Strong winds carry particles of sand aloft, but generally confined to less than 50 feet (15 metres), especially common in arid and semi-arid environments. A dust storm is also characterised by strong winds but carries smaller particles of dust rather than sand over an extensive area.
  • Tornado: A violently rotating column of air that reaches the ground or open water (waterspout).
  • Lightning: A high-voltage, visible electrical discharge produced by a thunderstorm and followed by the sound of thunder.
  • Winter storm, blizzard: A low pressure system in winter months with significant accumulations of snow, freezing rain, sleet or ice. A blizzard is a severe snow storm with winds exceeding 35 mph (56 km/h) for three or more hours, producing reduced visibility (less than .25 mile (400 m).
  • Orographic storm (strong wind): Differences in air pressure resulting in the horizontal motion of air. The greater the difference in pressure, the stronger the wind. Wind moves from high pressure toward low pressure.  
  • Extratropical storm: A type of low-pressure cyclonic system in the middle and high latitudes (also called mid-latitude cyclone) that primarily gets its energy from the horizontal temperature contrasts (fronts) in the atmosphere.
  • Tropical storms: A tropical cyclone originates over tropical or subtropical waters. It is characterised by a warm-core, non-frontal synoptic-scale cyclone with a low pressure centre, spiral rainbands and strong winds. Depending on their location, tropical cyclones are referred to as hurricanes (Atlantic, Northeast Pacific), typhoons (Northwest Pacific), or cyclones (South Pacific and Indian Ocean) (UNDRR, Sendai Framework).

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Related content on the Knowledge Portal

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    Source : Glide number

     

    Tropical Cyclone AILA hit the coast of West Bengal on 25 May 2009, affecting Satkhir, Kulna, Bagerhat, Pirojpur, Jhalokati, Barguna, Patuakhali, Bhola and Barisal districts. More that 3 million of people were affected by the cyclone.

    Source : Charter activation

     

    Tropical Cyclone Aila - May 2009 - ressources from OCHA/reliefweb, click here

    Map ressources :

    ...

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    Source : Glide number

     

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    Source : Glide number

     

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    Source : Glide number

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    Source : Glide number

     

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    Source : Glide number

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    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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  • Three people were killed and 800 made homeless.

    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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    Source : Glide number

Term Parents

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