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

  • On 03 August 2009, Typhoon "Kiko" (MORAKOT) entered east northeast of Luzon, Philippines as a tropical depression and intensified into a typhoon with maximum center wind of 140 kph. The southwest monsoon enhanced by the said typhoon brought occasional to frequent rains over extreme northern Luzon which resulted to widespread flooding in northern and central Luzon, occurrence of 8 landslide incidents, swelling of 5 rivers, breaching of earth dikes and retaining and sea walls. As of 14 August, 18,618 families or 94,211 persons in 4 cities and 19 municipalities in 11 provinces of Regions I, II, III, IV, VI, XI, NCR and CAR were affected.

    Source : Glide number

    Typhoon Morakot hit the coast of South Taiwan on 5 August 2009, as a major Category 4 storm. The thyphoon moved on to China, during the weekend, and up to 1 million people have been evacuated…

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  • Heavy rainfall on 9-11 August due to the typhoon 0909(Etau) has caused mud slide and flood in Kinki, Chugoku, Shikoku, Kyusyu districts. As of 13 August, 27 people are reported killed and missing, 18 people injured, 10 houses totally destroyed, 7 houses half destroyed, 32 houses partially destroyed, 1,300 houses flooded above floor level and 3,353 houses flooded below floor level.

    Source : Glide number

  • 5 provinces in the southeast mainland China have been hit by Typhoon Morakot. As of August 11, Typhoon Morakot had killed 8 people on the Chinese mainland, forced some 1.57 million people to be relocated and damaged over 10,000 houses, caused direct economic losses 9.72 billion yuan (CHF 1.5 billion)

    Source : Glide number

    Typhoon Morakot hit the coast of South Taiwan on 5 August 2009, as a major Category 4 storm. The thyphoon moved on to China, during the weekend, and up to 1 million people have been evacuated along the east coast.

    Source : Charter  for "Space and Major Disasters"

    Ressources from OCHA/Reliefweb, click here

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  • GDACS Red Alert issued. Up to 10.39 million people can be affected by wind speeds of hurricane strength or above. In addition, 1.06 million people are living in coastal areas below 5m and can therefore be affected by storm surge.

    Source : Glide number

    Typhoon Morakot hit the coast of South Taiwan on 5 August 2009, as a major Category 4 storm. The thyphoon moved on to China, during the weekend, and up to 1 million people have been evacuated along the east coast.

    Source : Charter  for "Space and Major Disasters"

    Ressources from ADRC, click here

    Ressources from OCHA/Reliefweb, click here

    read more
  • On July 2, a storm hit the area of River Region affecting 2350 persons. A total of 327 families were displaced to neighbours and relatives.

    Source : Glide number

     

    Ressources from OCHA/Reliefweb, click here

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  • NDCC issued situation report and warning in Luzon.

    Sources : Glide number

  • Tropical storm Andres. Warning issued for the southwestern coast of Mexico.

    Source : Glide Number

  • 20 dead and 46 seriously injured in central China's Henan province. Uprooted trees, damaged homes, flattened crops, and water and electricity supplies cut.

    Source : Glide number

     

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  • Cyclone AILA ripped coastal West Bengal on 25 May 2009 unleashing storms that uprooted trees, electricity poles and thatched homes, leaving a trail of destruction in its wake, killing approx 30 people and affecting 100,000 others. A severe storm with a wind speed of 110 kmph accompanied by heavy rainfall preceded the cyclone ripping through the districts of Kolkata, North and South 24 Parganas, Howrah and Hoogly. The coastal blocks like Sagar, Namkhana, Kakdwip and also Patharpraima, Canning, Basanti, Mathurapur and Kultali have all been severely affected and casualties have been reported. The West Bengal state?s Disaster Management Minister told BBC that 100,000 people had become homeless. The accompanying rains caused water-logging in large parts of the city, while power supply remained erratic and several flights were cancelled. Nearly four people were killed and 15 injured in Kolkata due to the storm that paralysed normal life. The usually bustling city streets were deserted…

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