Unlike many typhoons that weaken quickly after landfall, Typhoon Dolphin kept bringing heavy rain as it pushed inland. After making landfall in eastern China, it turned northwestward, carrying large amounts of warm, moist air northward and leaving parts of Henan province under torrential rain since Monday. The province has raised a red alert and activated a Level II emergency response.

An unusual downpour

Dolphin held onto its energy because of its extensive cloud system and abundant moisture. Its circulation kept transporting warm, humid air to the north, and when that air met mountain ranges it was forced up the slopes, cooling and condensing into intense precipitation. Henan sits among several mountain systems, including the Taihang, Songshan, Dabie and Funiu mountains, and the heavy rain followed.

The rainfall in numbers

As of 10 am Wednesday, average precipitation across Henan had reached 112.8 millimeters. The heaviest fell at the Changcun meteorological station in Pingdingshan city, where the cumulative total reached 435.7 millimeters. Kaifeng, Shangqiu, Pingdingshan, Luohe and Xuchang all saw significant rain.

Response and impact

Facing the severe conditions, authorities raised the warning to the highest red level and activated a Level II emergency response, the second-highest in the country. A chief forecaster at the Henan Meteorological Observatory cautioned that, given the overlap between areas that have already had heavy rain and those still forecast to receive it, alerts should be issued for flash floods and geological hazards in the Funiu and Songshan mountains.

Agriculture and travel were also affected. In some villages in Nanyang, corn was flattened or submerged by the rain, and some corrugated iron sheds and asbestos tile structures were damaged. At the same time, transport hubs such as Zhengzhou East Railway Station were crowded, and many travelers saw their plans disrupted.

Forecasters expect the rain to ease markedly on Thursday and Friday. Even so, after the soaking, the risk of flash floods and landslides in mountainous areas cannot be ignored, and vigilance still needs to be kept up.