Monsoon withdrawal conditions likely to start next week: IMD

The forecast added that reduced rainfall activity is likely to continue over northwest and adjoining west central India during the next five days.

The normal date of withdrawal of the southwest monsoon from the extreme parts of Rajasthan is September 17.

For withdrawal of monsoon from the western parts of northwest India, the IMD considers factors including dry weather over the area for five days, the establishment of an anticyclone in the lower levels of the atmosphere, and “considerable reduction in moisture content.”

Parts of Rajasthan and Gujarat recorded heavy rainfall over the past week on account of a low-pressure system and an associated cyclonic circulation.

IMD scientist, Kuldeep Srivastava said that some activity over northwest and western India is set to continue over the next few days as well. The IMD forecast said that eastern UP is likely to see widespread rainfall on September 22, while rainfall is also likely over the northern part of the Konkan region on September 24 and 25. Delhi is likely to see very light rainfall on Friday and Saturday.

After what was the country’s driest recorded August, rainfall in some parts picked up in September. From June 1 to September 20, the country recorded 761.3 mm of rainfall, 7% short of the normal of around 822 mm. Till August 31, the country saw rainfall that was 10% short of normal.

For the monsoon season so far, east and northeast India have recorded a 21% deficit in rainfall, while northwest India and central India have seen near normal rainfall with 2% above normal and 3% below normal rainfall respectively. Rainfall in the southern peninsula so far this season is 11% short of the normal, which is still within the IMD’s ‘normal’ range.

IMD data for the states shows that till September 21, Kerala, Karnataka, Bihar, Jharkhand, Tripura, and Manipur recorded deficits in monsoon rainfall. Of these states, the largest deficit is in Manipur (45%) followed by Kerala (39%). Gujarat, Himachal Pradesh and the Andaman and Nicobar Islands are the only states/UTs to have recorded an excess, while all other states and UTs have recorded rain in the normal range.

The IMD had said in its forecast for the month of September that rainfall over the country is likely to be ‘normal’ or 91% to 109% of the long period average.

Weak El Nino conditions are currently prevailing over the equatorial Pacific Ocean, while it is set to intensify and continue up to early next year, according to the IMD. El Nino conditions refer to a warming of equatorial Pacific Ocean waters and are usually associated with suppression of rainfall. The IMD has also said that “border line positive” Indian Ocean Dipole (IOD) conditions are prevailing over the Indian Ocean and positive IOD conditions are likely to strengthen during the upcoming months. A positive IOD is expected to counter, to some extent, the adverse impact of El Nino conditions on rainfall.