Monsoon remains weak; may pick up by last week of June: Meteorologists

Monsoon continued to be weak on Monday with some meteorologists flagging that it may revive only around last week of June.

The northern limit of monsoon has hardly progressed since June 11. It continues to pass through Navsari, Jalgaon, Amravati, Chandrapur, Bijapur, Sukma, Malkangiri, Vizianagaram, and Islampur. There is a 20% rain deficiency over the country since June 1 with 68% deficiency over northwest India; 29% deficiency over central India; 20% deficiency over east and northeast India and 17% surplus over peninsular India.

“Conditions are favourable for further advance of Southwest Monsoon into some more parts of Maharashtra, Chhattisgarh, Odisha, Coastal Andhra Pradesh & Northwest Bay of Bengal, some parts of Gangetic West Bengal, remaining parts of Sub Himalayan West Bengal and some parts of Bihar during next 4 days,” India Meteorological Department (IMD) said on Monday in its bulletin.

But some models have indicated that monsoon revival will happen towards end of the month and will be active over northwest India only in July.

“Northwest India can expect widespread rainfall in the first fortnight of July,” said M Rajeevan, former secretary, ministry of earth sciences and climate scientist.

“Models (@ECMWF @Indiametdept) suggest after a hiatus in its advance, monsoon is reviving during last week of June, will advance further & cover the whole country by July first week. Really a good news, but forecast uncertainty remains,” Rajeevan wrote on X with models indicating dry conditions over northwest India till June 24. The models are indicating widespread rainfall between July 1 to 8 over NW India.

IMD’s extended range forecast is also indicating a marginal revival after June 20 and widespread rainfall by July 4.

Heat wave to severe heat wave conditions are likely to continue over many parts of North India during next two days and gradually abate thereafter under the influence of approaching western disturbance towards Northwest India.

IMD’s data also indicated that minimum temperatures are in the range of 28 to 33 degree C over northwest and central India which are above normal by 3-6 degree C. This indicates that there is heat stress both during the day and night over these regions. Maximum temperatures are in the range of 44-46 degree C in most parts of Punjab, Haryana-Chandigarh-Delhi & Uttar Pradesh; in many parts of north Rajasthan & north Madhya Pradesh; and in isolated pockets of Bihar & Jharkhand. These are above normal by 4-8 degree C over these regions. The highest maximum temperature of 47.6 degree C was reported at Prayagraj (East Uttar Pradesh) on Sunday.

Heat wave to severe heat wave conditions are very likely in many/most parts of Uttar Pradesh until June 19 and in some parts of Punjab, Haryana-Chandigarh-Delhi on June 18; in isolated/some parts of Himachal Pradesh & Bihar on June 18 and decrease in intensity thereafter over above regions.

Heat wave conditions are very likely in isolated parts of Jammu-Kashmir, north Madhya Pradesh and north Coastal Andhra Pradesh on June 18; north Rajasthan till June 19. Warm night to severe warm night conditions are very likely in isolated pockets of Uttar Pradesh on June 18 and warm night conditions in isolated pockets of Punjab, Haryana-Chandigarh-Delhi on June 17; East Madhya Pradesh on June 18. Hot and humid weather is very likely over Odisha till June 19; Gangetic West Bengal on June 18 and Jharkhand on June 20.

Meanwhile, a cyclonic circulation lies over northeast Assam, and a north-south trough runs from north Bihar to southern parts of Gangetic West Bengal in lower tropospheric levels. Strong southwesterly/southerly winds are prevailing from Bay of Bengal to northeastern states in lower tropospheric levels. Under their influence, widespread light to moderate rainfall accompanied with thunderstorm, lightning & gusty winds (30-40 kmph) are likely over Arunachal Pradesh, Assam & Meghalaya, Nagaland, Manipur, Mizoram & Tripura and Sub Himalayan West Bengal & Sikkim during next five days.

Isolated heavy to very heavy rainfall is very likely over Sub-Himalayan West Bengal & Sikkim, Assam, Meghalaya, Arunachal Pradesh till June 21; Nagaland, Manipur, Mizoram and Tripura till June 19 with isolated extremely heavy rainfall over Assam & Meghalaya and Sub-Himalayan West Bengal till June 19; Arunachal Pradesh on June 19 and isolated exceptionally heavy rainfall over Meghalaya on June 18.