Heatwave conditions and delayed monsoon have aggravated Jharkhand's rainfall deficiency to 54 per cent and it may rise further as monsoon onset over the state is expected around June 19, a weather official said on Friday. 

Most parts of Jharkhand have been simmering over 40 degrees Celsius with Daltonganj recording the state's highest maximum temperature at 46.5 deg C on Saturday. The current progress of the monsoon is tardy. 

It is likely to get momentum after June 16 and we are expecting the onset of monsoon over Jharkhand around June 19," Abhishek Anand, in charge of Ranchi Meteorological Centre. 

The normal date for monsoon onset in Jharkhand is June 10. However, it has been reaching Jharkhand between June 12 and June 25 since 2010, according to the monsoon onset record at the Met office. 

Anand said the current situation suggests that rainfall might be deficient in June and it might increase in July. Jharkhand has received a mere 20.2 mm rainfall from June 1 to June 13 against the normal rainfall of 43.4 mm, which is 54 per cent deficient. 

The rainfall count for the four-month rainy season starts from June 1. Meanwhile, severe heatwave continues unabated in parts of Jharkhand.