The western disturbance that crosses the international border and rolls into North-West India, is forecast to suddenly acquire depth and intensity and trigger some weather in the region.
Earlier in February, a series of such monsters had made back-on-back appearances and sprayed snow, ice and rain in the hills and plains at times accompanied by hailstorm.
While crossing the border, the sheer depth and intensity caused them to sweep through even peninsular India, and in a rare feat, generated hailstorms in Central India and adjoining peninsular India.
These systems were largely instrumental in bringing rain into most of North-West, Central and East India. A couple of them had interacted with weather system in the South to drop rain there also.
In the instant case, the deep and intense (active) western disturbance is forecast to enter North-West India early next week.
The system could feature a likely low pressure area embedded into it, which signals the strength and intensity of the western disturbance.
The ‘low’ is shown as sitting smack on the Southwest Rajasthan border on Tuesday, and will weaken immediately as it encounters the desert region.
But associated weather would likely have been triggered in the form of high winds, thunderstorms and rain across the plains as it moves north-northeast.
This is because maximum temperatures are forecast to rise by 2-3 deg Celsius over the plains of North-West and adjoining East and Central India.
Cooler winds blowing across the border into the plains would thus trigger a lot of churn in the atmosphere and therefore associated weather.
Meanwhile on Friday, troughs with likely implicit weather ran down from Vidarbha to south Tamil Nadu across interior Andhra Pradesh and from west Assam to north Bay of Bengal.
The latter seems to be the more volatile, with thunder squall being forecast over Arunachal Pradesh, Assam, Meghalaya, Nagaland, Manipur, Mizoram and Tripura during next two days.
The India Meteorological Department has forecast rain or thundershowers for south Karnataka, Tamil Nadu, Kerala and Lakshadweep.