Holidaymakers throughout China were preparing for potential transportation disruptions.
The weather bureau issued a warning on Friday, indicating that heavy fog and haze would envelop regions from Hebei province in the north to southern Shanghai over the next 24 hours.
The Central Meteorological Observatory issued its initial red alert for fog in 2017.
Improvement in conditions was anticipated from Saturday evening, coinciding with the expected arrival of a cold wave of air sweeping across the country.
The National Meteorological Centre announced the anticipation of severe foggy conditions in various regions starting Friday morning.
These areas include parts of the northern province Hebei, central province Henan, and eastern provinces Anhui, Jiangsu, Zhejiang, and Shandong, as well as the municipalities Shanghai and Chongqing.
Dense fog is predicted specifically in parts of Hebei, Shandong, Anhui, Jiangsu, and Shanghai, resulting in low visibility of less than 200 meters and less than 50 meters in some areas.
In the north and areas between the Yellow River and Huai River, light to moderate haze is forecast, with heavy haze affecting Tianjin, Hebei, Shandong and Henan.
The forecaster said the severe weather was due to high humidity and poor atmospheric diffusion conditions.
China has experienced a year of climate extremes.
Last week, most of the country was hit by a cold snap that rewrote records with sub-freezing temperatures, in contrast to the summer, when scorching heat that breached 52 degree Celsius (125.6 Fahrenheit) in the northwest blistered the country.
Record rainfall in Beijing and flooding in other regions were also consequences of the summer storms.
The central observatory issued guidance on Friday, urging the public to stay updated on weather and traffic alerts.
Additionally, it advised residents in certain areas of Shandong, Anhui, and Jiangsu to minimize outdoor activities unless absolutely necessary.
“You can’t see clearly the road conditions and traffic lights ahead,” the observatory said on social media.
