Rainfall In Cherrapunji

Cherrapunji pronunciation (lately more used the historical name Sohra, also spelled as Cherrapunjee and Charrapunji), is a town in East Khasi Hills district in the Indian state of Meghalaya. It is credited as being the wettest place on Earth. However, nearby Mawsynram has more rainfall nowadays.

It has an average elevation of 1,484 metres (4,869 ft) sits on a plateau in the southern part of the Khasi Hills, facing the plains of Bangladesh. The plateau rises 600 meters above the surrounding valleys.



Soils on the plateau are poor due to deforestation and washout caused by heavy rains. Due to winter droughts the vegetation in this location is even xerophytic in spite of the fame of Cherrapunji as extremely wet place. Additional pressure on local ecosystems is created by rapid increase of population - from a Sohra area population of 7,000 in 1960, it grew to over 100,000 by 2000.

Valleys around Cherrapunji however are covered with lush and very diverse vegetation, containing numerous endemic species of plants, including Meghalaya subtropical forests.



Cherrapunji's yearly rainfall average stands at 11,777 millimetres (463.7 in).[4] This figure places it behind only nearby Mawsynram, Meghalaya, whose average is 11,873 millimetres (467.4 in). Cherrapunji receives both the Southwest and Northeast monsoon showers which give it a single monsoon season. It lies in the windward side of the Khasi Hills. Orographic precipitation results, and monsoon winds are forced to deposit much of their moisture. In the winter months it receives the northeast monsoon showers which travel down the Brahmaputra valley.

It holds two Guinness world records for receiving the maximum amount of rainfall in a single year: 22,987 millimetres (905.0 in) of rainfall between August 1860 and July 1861 and for receiving the maximum amount of rainfall in a single month: 9,300 millimetres (370 in) in July.



Cherrapunjee receives rains from the Bay of Bengal arm of the Indian summer Monsoon. The monsoon clouds fly unhindered over the plains of Bangladesh for about 400 km. Thereafter, they hit the Khasi Hills which abruptly rise out of the plains to reach a height of about 1370 m above mean sea level within of 2 to 5 km. The geography of the hills with many deep valleys channels the low-flying (150–300 m) moisture-laden clouds from a wide area to converge over Cherrapunji. The winds push the rain clouds through these gorges and up the steep slopes. The rapid ascent of the clouds into the upper atmosphere hastens the cooling and helps vapours to condense. Most of Cherrapunji's rain is the result of air being lifted as a large body of water vapour. The extremely large amount of rainfall at Cherrapunji is perhaps the best-known feature of orographic rain in northeast India.

Occasionally, cloudbursts can occur in one part of Cherrapunji while other areas may be totally or relatively dry depicting high spatial variability of rainfall. Atmospheric humidity is extremely high during the peak monsoon period.

The major part of the rainfall at Cherrapunji can be attributed to the orographic features. When the clouds are blown over the hills from the south, they are funneled through the valley. The clouds strike Cherrapunjee perpendicularly and the low flying clouds are pushed up the steep slopes. It is not surprising to find that the heaviest rainfalls occur when the winds blow directly on the Khasi Hills.

A notable feature of monsoon rain at Cherrapunji is that most of it falls in the morning. This could be partly due to two air masses coming together. During the monsoon months, the prevailing winds along the Brahmaputra valley generally blow from the east or the northeast, but the winds over Meghalaya are from the south. These two winds systems usually come together in the vicinity of the Khasi Hills. Apparently the winds that are trapped in the valley at night begin upward ascent only after they are warmed during the day. This explains, partially, the frequency of morning rainfall. Apart from orographic features, atmospheric convection plays an important role during the monsoon and the period just preceding it.