Southwest Monsoon has been waiting in the wings for a very long time and the northern limit continues to hold over Ambala and Amritsar. Monsoon was rather early to reach these parts on 13th June and has not budged thereafter. This is one of the longest waits on record where the monsoon was stuck for nearly a month. Monsoon is expected to advance further remaining stationary for nearly 4 weeks. It is likely to jump-start by 09th-10th July ending the longest haul anytime soon.
Only one monsoon low formed over the Bay of Bengal, in June which expedited the reach of monsoon over the eastern and central parts of the country. Monsoon reaching North India has always been an arduous task for more than one reason. Monsoon systems forming in the Bay of Bengal are the main drivers of monsoon pulse. These are also responsible for establishing monsoon trough, another important factor and feature to carry the rains to the hinterland of North India. Monsoon systems appearing over the Bay of Bengal take about 3-4 days to reach North and West India. During this period, they shed moisture and lose energy to go weak. Additional push is needed either in the form of an active monsoon trough or a strong western disturbance to infuse fresh charge and enhance their reach.
Environmental conditions are becoming favorable to strengthen the monsoon flow of easterly winds across Indo Gangetic plains commencing on 07th July. A pair of cyclonic circulations will move in tandem across the eastern and central parts of the country between 07th and 15th July. A low-pressure area may also form with the second cyclonic circulation around 11th July. This will revive the monsoon activity over most parts of the country, particularly the central region. Also, a western disturbance will arrive over North India and move across between 10th and 14th July. Such a situation will accentuate the rainfall activity over most parts of North India from 10th July onward.
Pre-monsoon activity will continue in the interim period over North India with thunderstorms and dust storms accompanied with strong winds over Punjab, Haryana, and Rajasthan. Prolonged blockage of monsoon is likely to lift soon with the monsoon current advance likely from 10th July onward. Subsequent 3-4 days will witness a fair amount of rain and thundershowers covering West Uttar Pradesh, Delhi, Punjab, Haryana, and Rajasthan. Monsoon feels with cloudy skies, drop in temperature and intermittent showers will break the jinx of the dry spell and usher in monsoon, albeit a delayed one.