Patna: At least two persons were killed at Bhargama in Araria district on Thursday after being struck by lightning.

A senior official in the disaster management department confirmed the deaths and said Rs 4 lakh each would be paid to family members of those killed. He also said the department was collecting reports from other places whether any casualty had taken place in the state because of rain and thunderstorm that hit several places in north Bihar from Wednesday evening onwards.

Attributing the weather phenomena to a Nor'wester, Patna MET office scientist Anand Shankar told The Telegraph: "A system had developed over central Uttar Pradesh on Wednesday afternoon and it entered Bihar from the north-western side the same evening, leading to rainfall and thunderstorm at several places in north Bihar on Wednesday evening and Thursday morning."

Nor'wester is a local thunderstorm, which is generally accompanied by rains and generally hits eastern states during April and May.

According to reports reaching Patna Met office from the districts, Forbesganj in Araria district received 36.2mm of rainfall while Muzaffarpur received 12.6mm of rainfall. Darbhanga (3.2mm) and Supaul (2.5mm) too received rainfall.

Shankar said the radar observation indicated rainfall had also taken place in West Champaran and East Champaran districts but the figures had not been made available till Thursday evening. Even Patna received a light drizzle on Thursday morning.

Giving reasons for the thunderstorm and rainfall witnessed in several north Bihar districts, Shankar said the surface wind, up to a height of 1.5km from the surface, was easterly, which was feeding moisture, whereas the upper air wind (above 1.5km above the surface) was westerly.

"Due to intermixing of two winds convective activities took place and the system developed, leading to thunderstorm and rainfall," he said.

Asked about likely weather conditions in the state in the coming days, the Met scientist said more thunderstorm accompanied by rain was likely to hit isolated places in the state in the next 3-4 days. "Favourable conditions are prevailing in and around Bihar, which could cause these weather-related events," he said.

Speaking about chances of thunderstorm hitting Patna, he said the system was likely to develop over north Bihar and it could not be said whether or not it would hit Patna.

The Indian Meteorological Department on Thursday afternoon issued a warning for Friday stating that thunderstorm accompanied by squall was likely at isolated places in Bihar.