India Meteorological Department (IMD) has predicted the possibility of isolated thunderstorms or dust storms over the vast plains of Haryana, Delhi, Rajasthan, Uttar Pradesh and Bihar during the rest of the weekend.
An evening bulletin on Thursday said that isolated rainfall occurred over north Rajasthan, Haryana, Madhya Pradesh and Vidarbha in northwest and central India.
Towards the east, rainfall has also been reported from Assam, Meghalaya, Arunachal Pradesh from presiding atmospheric features.
In the south, Kerala and Andaman and Nicobar Islands benefited as an easterly wave persisted over southeast Bay of Bengal.
A weather-making upper air cyclonic circulation has showed itself up over Haryana and neighbourhood.
To the immediate east, a north to south upper air trough ran down from Bihar to south Tamil Nadu across Chhattisgarh and Andhra Pradesh.
This churn in the atmosphere could be the prelude to the advent of the seasonally violent weather, called locally as “andhis,” triggered when cooler and moisture-laden northwesterlies force themselves downstream over the heated-up plains to the east-southeast.
At the far end to the southeast, they could spark the flare-up of severe thunderstorms, known locally as Nor'westers, given the direction from where they originate, or Kal Baisakhi, for the damage to life and property they portend.
Localised cyclonic circulations in the lower levels, one of which lingers over the Assam and Meghalaya region, mop up incremental moisture from the Bay of Bengal to add to the strength and intensity of the storms.
These forecasts need to be read in the context of expected arrival of a fresh western disturbance over the next couple of days.
The IMD has maintained the forecast for a low-pressure area springing up as the easterly wave peaks in activity.
Maximum temperatures changed little over the country during the day on Wednesday.
MERCURY TRENDS
They were above normal by 2 to 5° C over parts of western Himalayan region, Punjab, Haryana and Delhi and by 2 to 3 deg Celsius over parts of west Uttar Pradesh and central, east and northeast India.
The highest maximum temperature of 41.5 deg Celsius was recorded, for the second consecutive day, at Gulbarga in Karnataka.
Satellite image early on Thursday morning revealed the presence of convective clouds over parts of south Bay of Bengal and Andaman Sea.
Forecast valid until Sunday said that fairly widespread rain or thundershowers would continue over the Andaman and Nicobar Islands