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

  • Powereful typhoon Mirinae (Santi) hit several provinces in the Philippines, dozens of houses in coastal areas were swept away, about 50 houses were also destroyed by strong winds.

    Source: http://www.glidenumber.net/glide/public/search/details.jsp?glide=18949.

  • The country prepared for the approaching Typhoon Lupit (locally known as Ramil), provoking serious concerns that an already battered population faces further hardships, including the threat of landslides and storm surges. The situation is exacerbated by the fact that the flooding caused by the two previous two typhoons has not receded, and current projections indicate that the soil has no more absorptive capacity with very limited possibilities for run-off.

    http://www.glidenumber.net/glide/public/search/details.jsp?glide=18938.

  • On 8 October 2009, a strong typhoon 0918(Melor) has struck Japan, leaving a trail of damage across the centre of the country. As of 9 October, 4 people are reported killed and missing, 119 people injured, 3 houses totally destroyed, 19 houses half destroyed, 754 houses partially destroyed, 261 houses inundated above floor level and 1,140 houses inundatad below floor level.

    Souce: http://www.glidenumber.net/glide/public/search/details.jsp?glide=18926.

     

     

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  • Tropical Storm Ketsana hit Southern Laos on 30/09/2009 early morning, Causing Widespread Flooding in 3 Provinces of Southern of Lao PDR. Based on the first Provincial Report, There are around 12 District Affected. Currently PDMC are Collecting Damage Data.

    Source: http://www.glidenumber.net/glide/public/search/details.jsp?glide=18919&record=2&last=4478

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  • At least nine people have died in Kampong Thom province in central Cambodia due to Typhoon Ketsana on 30 September 2009.

    Source: http://glidenumber.net/glide/public/search/details.jsp?glide=18917.

  • Typhoon Parma, 180 km (110 miles) northeast of the island of Catanduanes in the central Philippines, gaining strength as it headed west-northwest toward the Luzon mainland, bringing heavy rain. Expected to make landfall near the northeastern province of Isabela on Saturday. Philippines declared a nationwide state of calamity. Concerns about the effects of more rain on the relief work in already flooded areas.

    The Philippines police say they will forcibly evacuate residents refusing to leave their homes in the direct path of an approaching super typhoon.

    Source: http://www.glidenumber.net/glide/public/search/details.jsp?glide=18918&record=1&last=1

    Source: http://www.gdacs.org/index.asp#TC_PARMA-09_1

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  • A serious typhoon is approaching Vietnam and it is expected to hit central provinces this evening. After the impact that it had in Philippines and its current evolution, it is expected that livelihoods and cities from Quang Binh to Quang Nam provinces will be severely affected.

    Source:UNDP Vietnam (29/09/2009)

  • Typhoon Ketsana hit the main island of Luzon on Sept. 26, with the resulting floods affecting tens of thousands of people and forcing the Philippines to appeal for international aid.

    By Sept. 28, about 150,000 had been displaced by the flash floods and the death toll had soared to 140. Officials expected the toll to rise with people looking for missing relatives and residents trapped in flooded houses two days after the typhoon dumped about 410 mm of rain in 24 hours - about the average amount of rainfall for an entire month.

    Officials said the economic damage from the worst rains on record in the Manila area was about 1.4 billion pesos ($30 million), including 500 million pesos in lost crops. Damaged roads and bridges accounted for most of the remaining costs.

    Source: Reuters AlertNet

    At least 54 people were killed as tropical storm Ketsana battered a wide area in the…

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  • Due to heavy rains, around 382 families, 995 persons, evacuated in 6 municipalities of the Laguna Province.

    Source: Glide number

  • Nine have died or have gone missing due to tropical depression Maring that spawned rains and landslides in northern Philippines while the number of affected people doubled to over 300,000.

    Source: Glide number

     

    Available Space-based Information for: Philippines - PARMA Tropical Cyclone -  2 October 2009


    Status Updated 12/10/2009

     

    UNOOSA/UN-SPIDER

    Email: un-spider [at] unoosa.org

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UN-SPIDER Regional Support Offices with hazard-specific expertise