Halong was over the Sea of Japan (East Sea) as of 3:00 pm (0600 GMT), some 100 kilometres (60 miles) west-southwest of the central city of Kanazawa, after making landfall on the largest and most populous island of Honshu.
Packing winds of up to 162 kilometres per hour, the typhoon was moving north-northeast at 35 kilometres per hour and expected to move away from the Japanese archipelago, the Japan Meteorological Agency said.

Vehicles drive down a flooded road in the city of Tsu, Mie prefecture as Typhoon Halong brings rain on.
But the weather agency maintained its highest warning against torrential rain for some areas of Honshu.
In southwestern Wakayama prefecture, a man who was apparently surfing on the Pacific coast went missing early Sunday, local police said.
"According to a witness, a man in a wetsuit was seen drifting about 30 metres offshore and then disappeared," said a local police spokesman.

Typhoon Halong floods the town of Hermosa, Bataan province, the Philippines on 05 August 2014.
The coastguard dispatched helicopters to the area, he said.
The storm injured at least 59 people throughout the country, public broadcaster NHK said.