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IMD alerts Himachal Pradesh, Uttarakhand as western disturbances interact with monsoon
Several weather systems are currently active across the country, with conditions favourable for the formation of a low-pressure area over the north Bay of Bengal.
The India Meteorological Department (IMD) on Monday said a fresh spell of heavy to very heavy rainfall is likely to lash northwest India over the next three days, with isolated extremely heavy showers (around 21 cm) expected in Himachal Pradesh, Uttarakhand and western Uttar Pradesh between till Tuesday.
The Met department also predicted intense rainfall activity over parts of western and coastal India later this week. Heavy to very heavy rain is likely over the Konkan region, Goa, central Maharashtra, Gujarat and coastal Karnataka between September 3 and 6. Isolated parts of Gujarat could witness extremely heavy rainfall on September 4 and 5, the forecast added.
In the past 24 hours, ‘heavy to very heavy’ rainfall (around 21 cm) was recorded at isolated places over Himachal Pradesh, Uttarakhand, Punjab, West Rajasthan and Telangana. Very heavy rainfall (12-20 cm) was recorded at isolated places over Haryana, Uttar Pradesh, East Rajasthan. Heavy rainfall (7-11 cm) was recorded at isolated places over Jammu, Chandigarh, Madhya Pradesh, Andaman and Nicobar Islands, Odisha, Chhattisgarh, central Maharashtra and Gujarat.
Several weather systems are currently active across the country, with conditions favourable for the formation of a low-pressure area over the north Bay of Bengal within the next 24 hours.
According to the IMD, the monsoon trough at mean sea level is running close to its normal position. An upper-air cyclonic circulation lies over the northeast Bay of Bengal and adjoining Myanmar coast in the lower and middle tropospheric levels, tilting southwestwards with height. Under its influence, the low-pressure system is expected to develop.
The weather department said one weather trough is extending from this circulation to north coastal Odisha in lower tropospheric levels. Another cyclonic circulation persists over northwest Rajasthan and adjoining areas, with a trough running from there to Jharkhand. In addition, a western disturbance is seen as a cyclonic circulation over Punjab and neighbouring Pakistan.
Under the influence of these systems, extremely heavy rainfall is very likely at isolated places over Himachal Pradesh, Uttarakhand & West Uttar Pradesh on September 1. Isolated heavy rainfall likely to continue over Jammu-Kashmir, Himachal Pradesh, Punjab, Haryana, Chandigarh from September 1-3; Uttarakhand and east Rajasthan till September 7; Uttar Pradesh on September 2; West Rajasthan till September 7 with isolated very heavy rainfall very likely over Jammu-KashmirLadakh on September 2 and 3; Himachal Pradesh, Uttarakhand, Punjab, Haryana, Chandigarh, West Uttar Pradesh on September 2.
A red alert has also been issued for most of northwest India, including Punjab, Haryana, Himachal Pradesh, Uttarakhand on Monday and for Himachal Pradesh and Uttarakhand on Tuesday.
IMD had said on Sunday that one of the main reasons for extreme rainfall and flash floods in August was because of the development of five active Western Disturbances (WDs), which then interacted with monsoon circulation and brought very heavy downpour in the northern states especially Jammu and Kashmir, Himachal Pradesh and Uttarakhand.
Even now, there is an interaction between a WD and monsoon, meteorologists said. WDs normally start impacting the western Himalayan region in October-November and are associated with winter rain in north India, they pass in higher latitudes during summer and monsoon.
“It is unusual for WDs to impact lower latitudes or the Indian region during monsoon. But it is happening frequently this year. Presently, there is an interaction between a WD and monsoon circulation. There are humid winds from Arabian Sea and Bay of Bengal. This may cause extreme rain once again in Himachal Pradesh, Uttarakhand, Jammu and Kashmir etc,” said Mahesh Palawat, vice president, climate and meteorology, Skymet.
