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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    Source : Glide number

  • Tropical storm ?Eric? descended on north-east regions of Madagascar on 19 January 2009, carrying heavy rain and winds. According to preliminary reports, approx. 1,000 remain homeless with another 1,700 impacted to varying degrees.

    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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  • 3 killed Source : Emdat
  • A fierce storm from the Atlantic Ocean hit southwestern France, leaving at least 15 people dead and one million homes without power. With torrential rains and winds approaching 175 kilometres an hour, the storm was described by weather forecasters as the region's worst in a decade.

    Source : International Charter for "Space and Major disaster"

     

    Map ressources :

    Adour River, Aquitaine region

    Aquitaine Region, France

    Aquitaine…

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  • 14 killed Source : Emdat
  • During the period towards end of December 2008 to the mid of January 2009, areas of Lake Victoria Basin, South-western highlands, Western areas and Central parts have experienced normal rains with pockets of heavy rains. Some areas experienced heavy downpours and wind that caused damage to houses and other buildings. The worst affected districts were Rukwa, Shinyanga and Dodoma.

    Source : Glide number

  • The west was bracing for the arrival of tropical cyclone Fanele. Heavy rains had already begun to fall over the north as the cyclone moved southwards, causing widespread flooding that left close to 250 people homeless in the Sofia region.

    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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  • Local storm and torrential rain occurred in the second subdivision and other neighbourhoods of Bangui, the capital of the Central African Republic (CAR), in the night of 17 to 18 January 2009, causing serious material damages and killing a 17-year old boy. A joint team from the Ministry of Family and Social Affairs, the CAR Red Cross Society (CAR RCS), local authorities and volunteers carried out an evaluation of the situation in the field and realized that most of the people affected were women, children and old persons. They also noticed that the victims have been sleeping on the floor and in a seriously mosquito-infected locality since the disaster occurred.

    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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  • The death toll in a storm that struck South Africa's KwaZulu-Natal province over the weekend has risen to 18, according to the South African news agency Sapa, citing government officials.

    Source : Glide Number

  • At 6:30 PM of January 3, 2009, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said the Low Pressure Area (LPA) East of Mindanao has developed into a Tropical Depression (TD) and was named "Auring". At this point the maximum sustained winds near the center is 55 kph and is moving Northwest at 7 kph. Public Storm Warning Signal Number 1 (PSWS#1) was raised at Eastern Samar, Western Samar, Leyte, Southern Leyte, and Surigao del Norte.Reports reaching the PNRC National Headquarters Operation Center (OpCen) in Port Area, Manila late yesterday said there were floodings in the provinces of Negros Oriental, Bohol and Samar in the Visayas; and Zamboanga del Norte, Iligan, Cagayan de Oro and Gingoog City in Western Mindanao.

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