The Ministry of Water Resources issued a red meteorological warning for mountain torrents at 8 am Monday and maintained a blue alert for floods, as 18 rivers across the country remained above warning levels.

China has a four-tier weather warning system, with red representing the most severe, followed by orange, yellow and blue.

As of 9 am Monday, 18 rivers in Heilongjiang, Hebei and Yunnan provinces and the Inner Mongolia autonomous region were still above warning levels, the ministry said in a media release, which was issued following a consultation meeting to analyze the country's flood control situation on Monday.

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The Hulan River, a tributary of the Songhua River, in Heilongjiang remained above its guaranteed water level, it said.

The guaranteed water level is a threshold at which flood-control facilities such as embankments are designed to operate safely.

The ministry said that from Monday to Wednesday, rainfall and inflows from upstream areas are expected to trigger major floods in the Hulan and also the Heilongjiang River.

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Some small and medium-sized rivers in rainstorm-hit areas, including the Ougen River, a tributary of the Songhua River in Heilongjiang, the Huangshui River, a tributary of the Yongding River in Shanxi province, the Qianyou River, a tributary of the Hanjiang River in Shaanxi province, the Enyang River, a tributary of the Qujiang River in Sichuan province, and the Longhe River, a tributary of the Yangtze River in Chongqing municipality, may also exceed warning levels.

From 8 am Monday to 8 am Tuesday, parts of northwestern Hubei province, southeastern Shaanxi and central Chongqing face a high risk of mountain torrents, with an orange alert in place. Some areas in central Chongqing are under a red alert, indicating a very high risk of such disasters.