Sunday, August 8, 2010

What is a cloudburst?


A cloudburst is an extreme form of rainfall with a fall rate of around 100mm per hour, sometimes mixed with hail and thunder, which normally lasts no longer than a few minutes but is capable of creating flood conditions.


They occur most often in desert and mountainous regions, and in interior regions of continental landmasses.


Generally cloudbursts are associated with thunderstorms. The air currents rushing upwards in a rainstorm hold up a large amount of water.

If these currents suddenly cease, the entire amount of water descends on to a small area with catastrophic force all of a sudden and causes mass destruction. This is due to a rapid condensation of the clouds.


Major Cloudburst Tragedies

Aug 17, 1998 — A massive landslide following heavy rain and a cloudburst at Malpa village in Kali valley of Kumaon killed 250 people including 60 Kailash Mansarovar pilgrims. Among the dead was Odissi dancer Protima Bedi.

Aug 31, 1960 –250mm of rain in 3hrs in Mandi and Suketi valley, Himachal Pradesh led to 103 deaths.

July, 1970 — Cloudburst in the upper catchment area led to a 15 metre rise in Alaknanda river. Entire river basin, from Hanumanchatti near Badrinath to Haridwar, affected; An entire village was swept away. Source– timesofindia

Record Cloudbursts

(Source-wikipedia)


Duration Rainfall Location Date
1 minute 1.9 inches (48.26 mm) Leh, Jammu & Kashmir, India 06 August, 2010
1 minute 1.5 inches (38.10 mm) Barot, Himachal Pradesh, India 26 November, 1970
5 minutes 2.43 inches (61.72 mm) Port Bells, Panama 29 November, 1911
15 minutes 7.8 inches (198.12 mm) Plumb Point, Jamaica 12 May, 1916
20 minutes 8.1 inches (205.74 mm) Curtea-de-Arges, Romania 7 July, 1947
40 minutes 9.25 inches (234.95 mm) Guinea, Virginia, USA 24 August, 1906

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