Monsoon trough shows clear signs of shifting northward and likely to cut across parts of Punjab, Haryana, Delhi and thence stretch along Indo- Gangetic plains. Presently, this feature is south of its normal position passing through Bikaner, Guna, Pendra, Baleswar and Bay of Bengal. The western end of the trough will shift faster than the eastern one and is likely in the next 24hr. Accordingly, the weather activity will pick up over North India for good number of days.
Under the influence of cyclonic circulation moving across Madhya Pradesh, South Rajasthan and Gujarat, the monsoon trough remained far south of its normal position. Strong easterlies swept across most parts of North India, including Delhi. These winds prevail even now and the change over will commence tomorrow. Increased humidity, drop in day temperatures, partly cloudy sky with drifting clouds and short duration light passing showers remained the hallmark for the last few days.
Western disturbance is likely to reach Western Himalayas tomorrow. This will be manifested as cyclonic circulation over North Pakistan, Jammu & Kashmir and North Punjab in the lower levels and trough aloft. Under its influence, the monsoon trough will gradually shift northward. It is expected to stay north of its normal position, in the close proximity of foothills of Punjab, Haryana, Uttrakhand and West Uttar Pradesh, up to the friction level of 3000 feet. This change will sustain for nearly one week or even more, keeping the weather activity live across mountains and plains of North India.
Punjab, Haryana, Delhi and Uttar Pradesh will experience prolonged active monsoon conditions between 28th July and 05th August. It may extend further for couple of days and the situation will be kept under observation. Short and temporary break in between, towards the afternoon hours will be rather common. Incidents of lightning, thunderstorm and squally winds are quite likely during this period. Light weather activity will commence today, with some moderate showers at few places. Intensity and spread will be on the rise tomorrow onward and will sustain for a week. Vigorous monsoon conditions can be expected along the foothills for 2-3days. Eastern parts of Uttar Pradesh reeling under severely parched conditions are expected to get some relief, more so during 2nd half of this period. Extreme southwestern parts of Punjab and Haryana region bordering Rajasthan may get excluded from any intense weather activity.