What is Cloudburst ?

A cloudburst is an extreme amount of precipitation, sometimes with hail and thunder, which normally lasts no longer than a few minutes but is capable of creating flood conditions. Colloquially, the term cloudburst may be used to describe any sudden heavy, brief, and usually unforecast rainfall.

Meteorologists say the rain fall rate equal to or greater than 100 mm (3.94 inches) per hour is a cloudburst.  The associated convective cloud, can extend up to a height of 15 km above the ground.

During a cloudburst, more than 20 mm of rain may fall in a few minutes. When there are instances of cloudbursts, the results can be disastrous. Cloudburst are also responsible for Flash flood creation.

Rapid precipitation from cumulonimbus clouds is possible due to so called Langmuir precipitation process in which large droplets can grow rapidly by coagulating with smaller droplets which fall down slowly.

Major cloudbursts....

Duration       Rainfall          Location        Date

1 minute       1.5 inches (38.10 mm)     Basse-Terre, Guadeloupe

26 November 1970

5.5 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

1 hour           9.84 inches (250 mm)      Leh, Ladakh, India  August 5, 2010 [

13 hours       45.03 inches (1,144 mm)            Foc-Foc, La Réunion

January 8, 1966

1 hour           5.67 inches (144 mm)      NDA, Pune, India    September 29, 2010 [1]

1.5 hours      7.15 inches (182 mm)      Pashan, Pune, India           October 4, 2010

10 hours       57.00 inches (1,448 mm)            Mumbai, India        July 26, 2005

20 hours       91.69 inches (2,329 mm)            Ganges Delta, India           January 8, 1966[

In the Indian subcontinent, a cloudburst usually occurs when a pregnant monsoon cloud drifts northwards, from the Bay of Bengalor Arabian Sea across the plains, then onto the Himalaya and bursts, bringing rainfall as high as 75 millimeters per hour.

Some Deadly Cloudbursts in India...

In Aug 1998: A cloudburst in gowalpara. 400 people died

On September 28, 1908 - A Cloudburst resulted in a flood where the Musi River was swollen up to 38–45 m. About 15,000 people were killed and around 80,000 houses were destroyed along the banks of this river.

In July, 1970 — Cloudburst in the upper catchment area led to a 15 metre rise in the Alaknanda river in Uttarakhand. Entire river basin, from Hanumanchatti near the pilgrimage town of Badrinath to Haridwar was affected. An entire village was swept away.[

On August 15, 1997, 115 people were killed when a cloud burst came bustling and trail of death are all that is left behind in Chirgaon in Shimla district, Himachal Pradesh.

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

On July 16, 2003, About 40 persons were killed in flash floods caused by a cloudburst at Shilagarh in Gursa area of Kullu,Himachal Pradesh.

On July 6, 2004, At least 17 people were killed and 28 injured when three vehicles were swept into the Alaknanda river by heavy landslides triggered by a cloudburst that left nearly 5,000 pilgrims stranded near Badrinath shrine area in Chamoli district, Uttarakhand.

On 26 July 2005, A cloudburst caused approximately 950 millimetres (37 in) of rainfall in Mumbai. over a span of eight to ten hours; the deluge completely paralysed India's largest city and financial centre leaving over 5000 dead.

On August 16, 2007, 52 people were confirmed dead when a severe cloud burst occurred in Bhavi village in Ghanvi,Himachal Pradesh.

On August 7, 2009, 38 people were killed in a landslide resulting from a cloudburst in Nachni area near Munsiyari inPithoragarh district of Uttarakhand

On August 6, 2010, in Leh, a series of cloudbursts left over 1000 persons dead (updated number) and over 400 injured in the frontier Leh town of Ladakh region in Jammu and Kashmir.

On September 15, 2010 cloud burst in Almora in Uttrakhand has drowned away two villages one of them being Balta, leaving a few people alive and rest entire village dead and drowned. Almora has been declared as a town suffering from the brunt of cloudburst by authorities of Uttrakhand. Had there been a bit more swaying of clouds, town of Ranikhet must have drowned also.

On September 29, 2010, a cloudburst in NDA (National Defence Academy), Khadakwasla, Pune, in Maharashtra state left many injured, hundreds of vehicles and buildings damaged due to this flash flood.

Again on October 4, 2010, a cloudburst in Pashan, Pune, in Maharashtra state left 4 dead, many injured, hundreds of vehicles and buildings damaged. The record books as the historical highest rainfall in intensity and quantity of the Pune city recorded since 118 years old (record of 149.1 mm in 24 hours)of October 24, 1892. In the history of IT (Information Technology) hub Pune, first time this flash flood also anable Pune people to for over night stay (sleep) in their vehicle, officies and what ever available shelter in the traffic jam.

October 4, 2010, a cloudburst in Pashan, Pune may be the world’s first predicted cloudburst, in well advanced. Since 2.30 pm in the afternoon of the day, a young weather scientist in the city was frantically sending out SMSes to the higher authorities warning of an impending cloudburst over the Pashan area. After taking the necessary precautions still 4 persons were dead including one young scientist.

On June 9, 2011, near Jammu, a cloudbursts left 4 persons dead and over several injured in Doda-Batote highway, 135 km from Jammu.Two restaurants and many shops were washed away.[

On 20 July 2011, a cloudburst in upper Manali, 18 km away from Manali town in Himachal Pradesh state left 2 dead and 22 missing

On September 15, 2011 a cloudburst was reported in the Palam area of the National Capital Territory of Delhi. The Indira Gandhi International Airport's Terminal-3 was flooded with water at the Arrival due to the immense downpour. Even though no lives were lost in the rain that lasted an hour was enough to enter the record books as the highest rainfall in the city recorded since 1959.

On September 14, 2012 in Rudraprayag district there was a cloudburst and 39 people died.

And this is the latest,on June 17, 2013 a cloudburst was reported in Kedarnath Rampada Region of Uttarakhand State. Over 500 feared killed to till date, it is anticipated that the death toll may rise during cleaning of debris to thousands more as still plenty of people are missing. It left approximately 84000 people stranded for several days. Indian Army and Central Command launched one of the largest and most extensive human rescue missions that had ever been launched in the history. It spread over 40,000 square kilometres. 45 choppers were deployed to rescue the stranded people.