The incoming western disturbance affecting the western Himalayas is now seen to being more productive than thought earlier and would set off weather over not just the hills but also over the plains over the weekend and into the next.

In fact, an India Meteorological Department (IMD) on Friday afternoon said that the westerly activity over northwest India is far from over with a follow-up system being forecast on Wednesday.

The IMD bulletin said that a fresh western disturbance would affect western Himalayan region from Tuesday onwards and adjoining plains from Wednesday onwards.

This is in line with international model prognostications made available much earlier and reported in these columns, which had suggested that the seasonal weather perturbations would continue unabated into the last week of the month.

Newly assessed weather conditions in the region suggest that minimum temperatures may not dip as predicted earlier and could, in fact, rise by 2 to 3 deg Celsius over the plains of northwest and adjoining central India thereafter.

This would happen as moisture fills the plains and affords some convection throwing up clouds and helping hold up the minimum temperatures.

Weather warnings issued by the IMD said that isolated thunder squalls or hailstorm may break out over Orissa, Chhattisgarh, Jharkhand, north Andhra Pradesh, Punjab, Haryana, Rajasthan and west Uttar Pradesh on Sunday.

Scattered rain or thundershowers with isolated hails or squalls would occur over coastal West Bengal, Orissa, Chhattisgarh, Vidarbha, Andhra Pradesh, Kerala and Tamil Nadu.

In this manner, the IMD has expanded further the coverage of the rains over east India and along the east coast and adjoining south peninsula over the next few days as had been forecast well in advance by global models.

An IMD update during the last 24 hours ending Friday morning said that isolated rain or snow was reported from Jammu and Kashmir, Himachal Pradesh and Uttarakhand.

It was in the form of fairly widespread rain or thundershowers over Arunachal Pradesh; scattered over Bihar, Assam and Meghalaya; and isolated over Nagaland, Manipur, Mizoram and Tripura.

Minimum temperatures fell by 2 to 3 deg Celsius over parts of Madhya Pradesh, Bihar, Uttar Pradesh, Arunachal Pradesh and Assam in the immediate wake of a prevailing western disturbance exiting the region. The lowest minimum temperature of 4.4 deg Celsius was recorded at Adampur in Punjab in the plains of the country.

As forecast already, fresh western disturbance would affect western Himalayan region during next 2 to 3 days and the plains of northwest India from Saturday evening or night onwards.