Severe Storm

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

  • The Active Low Pressure Area (ALPA) intensified into a tropical depression and was named "Caloy". As early as 11:00 AM, 18 July, heavy rains and strong winds triggered flashflood affecting 111 families in the Municipality of Dingalan, Aurora Province. Twenty seven (27) families who were affected by flashflood in the Municipality of Baler, Aurora, were rescued by the Philippine Army.

    Source: glidenumber
     

     

     

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  • Philippines raises alert in rice areas as typhoon Conson moving towards Luzon's central lowlands.

    Source: http://www.glidenumber.net/

  • A tropical storm warning is in effect for the coast of Belize, Yucatan (Mexico) and Belize.

    Source: glidenumber

  • GDACS issued red alert as Tropical Cyclone PHET-10 of Saffir-Simpson Category 4 affected 295 thousand people with winds above 39mph (63 km/h) and 16.4 million people with hurricane wind strengths (74mph or 119 km/h). In addition, 164 thousand people are living in coastal areas below 5m and can therefore be affected by storm surge.

     Source: glidenumber

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    Status Update: 14/06/2010

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    Contacts:

    UNOOSA/UN-SPIDER:
    Focal Point: Mr. Shirish Ravan
    Email: 

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  • The first named tropical storm of the 2010 Pacific hurricane season "Agatha" caused severe rainfall in the departments of Escuintla, Suchitepéquez, Retalhuleu, San Marcos, Quetzaltenango, Huehuetenango, Totonicapn, Sololá, Chimaltenango and Guatemala. Guatemalan authorities report 12 deaths, 22 people missing and that 7,627 people have been affected to some degree by the storm and 4,975 people have been directly affected by the effects of the storm.

    Source: glidenumber

     

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    Status Update: 02/07/2010

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    Contacts:

    UNOOSA/UN-SPIDER…

    read more
  • A cyclone intensified over the Bay of Bengal on Wednesday, forcing a southern Indian oilfield to shut and cut its gas output, and the evacuation of some 50,000 people in the region, officials said.

    Source: http://www.glidenumber.net/glide/public/search/details.jsp?glide=19107

  • Gales and hailstorms killed at least 39 people, injured hundreds and destroyed hundreds of homes in southwest and central China.

    Source: GlideNumber

  • Violent wind and tornado hit the Mouila locality in the Ngouni region of Gabon on 16 April, 2010. So far, the disaster has caused several damages: deterioration of about 280 houses, destruction of household basic property, and the obstruction of roads by uprooted trees.

    Source: GlideNumber

  • The nor'wester that played havoc in eastern India on the night of 14 April 2010 also hit border districts of Dinajpur, Rangpur, Nilphamari, Lalmonirhat, Kurigram in Bangladesh. Some adjacent districts including Gaibandha, Sirjaganj and Bogra were also affected.

    Source: GlideNumber

  • A storm in the eastern Indian state of West Bengal has killed 31 people and destroyed 50,000 homes.

    Source: GlideNumber

Term Parents

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