Jamshedpur, April 25: Daytime readings crossing the oppressive 40-degree mark in many parts of Jharkhand today prompted weathermen to issue a heat wave warning in isolated pockets.

"The state is in the grip of dry westerly winds, which are pushing up maximum temperatures. The Celsius surge is likely to continue for the next 72 hours because we don't see any rain relief," said D.G. Hedau, a senior official of Ranchi Meteorological Centre.

He added that several places in southern Jharkhand, including Jamshedpur at 43.9°C, witnessed temperatures four notches above normal today.

Met officials pointed out that the Celsius surge combined with a sharp drop in minimum relative humidity was resulting in dry heat. The Loo is sweeping through the plains, including Jamshedpur.

"The hot and dry weather is likely to continue because we do not see signs of change in the wind pattern. Rainfall isn't likely in the next couple of days," said a duty officer at the Sonari weather office.

Weathermen in Ranchi said the stifling conditions were likely to last at least till Thursday with the IMD office ruling out Nor'wester relief in the next three days. "Rain and thunder is expected after 72 hours," said a duty officer.

Jamshedpur recorded its highest maximum this season at 43.9°C against 43°C yesterday. Day readings in neighbouring Ghatshila (East Singhbhum) and Chaibasa (West Singhbhum) also soared beyond 43°C today. Capital Ranchi, its altitude advantage notwithstanding, touched the oppressive 40-degree mark, the temperature being three notches above normal.

The maximum reading also saw a rise in Daltonganj, where the local IMD observatory noted 42.4°C against yesterday's 41.8°C. The mercury march continued unabated in places like Dhanbad, Bokaro, Hazaribagh, Giridih, Koderma and Jamtara, courtesy the dominating westerly winds.