By Jayashree Nandi
PUBLISHED ON SEP 15, 2021 05:14 PM IST
Widespread and intense rainfall activity is likely over many parts of the country including northwest India at least for a week. Monsoon is normally expected to withdraw from northwest India September 17 onwards
Monsoon has picked up this month with the formation of the season’s first depression on Sunday. The system brought widespread rains to central India and the west coast bringing down monsoon deficiency from 9% at the end of August to only 5% on September 15. Monsoon rains are nearing the normal category which is 104% to 96% of the long period average.
The long period average considered for the period of 1961 to 2010 is 88cm. Rainfall between 96% -104% of long period average is considered ‘normal’; between 90% – 96% is considered ‘below normal’ and 104 -110% is considered ‘above normal’ by IMD.
Widespread and intense rainfall activity is likely over many parts of the country including northwest India at least for a week. Monsoon is normally expected to withdraw from northwest India September 17 onwards. “Monsoon has been very active in September. The well marked low pressure area over north Madhya Pradesh is moving towards northwest India. The monsoon trough is also expected to move northwards. The combination of these factors will bring widespread rain and thundershowers to Delhi, Haryana, Uttar Pradesh etc. Meanwhile, another cyclonic circulation is likely to develop over Bay of Bengal on Friday which is also likely to bring rain to east and central India. We don’t see any indication of monsoon withdrawal at least for a week,” said Mahesh Palawat, vice president, climate change and meteorology, Skymet Weather.
“The synoptic conditions are very good for rain this month. Three low pressure systems have developed out of which one was a deep depression which has now weakened to a well marked low pressure area over central parts of north MP. This system will bring widespread rains to northwest India. Some models are indicating an other cyclonic circulation developing over Bay of Bengal. These features have led to a reduction in monsoon deficit bringing it close to normal category,” explained K Sathi Devi, head, national weather forecasting centre.
A well marked low pressure area is lying over central parts of north Madhya Pradesh and neighbourhood. It is likely to move west-northwestwards during the next two days and weaken thereafter. A cyclonic circulation is lying over south Gujarat region and neighbourhood. The monsoon trough is lying south of its normal position. It is very likely to remain south of its normal position during next 3 days. A cyclonic circulation is likely to develop over north Bay of Bengal on Friday. It is likely to move west-northwestwards towards Odisha- West Bengal coast during subsequent three days.
Due to movement of the well marked low pressure areas and the cyclonic circulation over south Gujarat, widespread rainfall with isolated heavy to very heavy rain is likely over Gujarat, West Madhya Pradesh, East Uttar Pradesh and East Rajasthan till Friday; over East Madhya Pradesh, Gangetic West Bengal, Odisha, Bihar, Jharkhand rain is likely to reduce from Friday.
Isolated extremely rain (over 20cm) is also likely over East Uttar Pradesh on Thursday. Scattered to widespread rainfall is very likely over all of northwest India (excluding Jammu, Kashmir &Ladakh and Himachal Pradesh) on Thursday and Friday. Isolated heavy rainfall is likely over Uttarakhand, West Uttar Pradesh, Haryana, and West Rajasthan till Saturday.
Very heavy rain is also very likely over Uttarakhand and west Uttar Pradesh on Thursday. Rainfall activity is likely to increase over Odisha &Gangetic West Bengal with widespread and heavy rain likely over the weekend.
There is a 5% rain deficiency over the country since June 1; 12% excess over peninsular India; 4% deficiency over central India; 11% deficiency over northwest India and 12% deficiency over east and northeast India. In June there was 9.6% excess rain; in July there was a 6.8% deficiency; 24% deficiency in August; in September there is 30.4% excess rain so far making it the rainiest month this monsoon.
(Source: https://www.hindustantimes.com/india-news/monsoon-conditions-active-likely-to-cause-rain-over-nw-india-for-next-2-days-101631706297730.html)