Zhang Hengde is a forecaster with the National Meteorological Center.
"The highest level can be expected on Tuesday and Wednesday morning. Heavy smog will be seen in central and south Beijing, central and west Tianjin, central and north Hebei, north Shandong and Henan. It will cause severe pollution."
To tackle the pollution, Hebei, which is home to six of the ten most polluted Chinese cities, as of November, issued its first red alert for smog on Tuesday noon.
All 11 cities in Hebei are expected to roll out strict measures including limitations on the number of vehicles on the roads.
Kindergarten, middle school, and primary school classes will be canceled.
The port city of Tianjin also issued its red alert, which will runs through Thursday.
Meanwhile a similar warning for severe air pollution expired in Beijing as of Tuesday night.
Zhang Hengde with the National Meteorological Center, says the capital city is to see the smog density reduced, though in a slow pace on Wednesday.
"Starting from Wednesday, a weak cold front from the north will affect North China's central and south regions, all the way down to the Huang-huai area. But it's not strong enough. So the smog will be reduced at a very slow pace. In Beijing, it will be weakened from Wednesday and dispelled a day after. And in Hebei it could be even slower and longer, if it's dispelled at all."
Beijing was hit with severe air pollution on Tuesday, with pollution levels reaching the highest grade on its pollution gauging system in the southern part of the city.
The Municipal Environmental Monitoring Center said the density of PM2.5 exceeded 500 micrograms per cubic meter in these areas.
Meanwhile, other parts of north China also witnessed some of the worst smog so far this year from Saturday.
Orange, yellow and blue alerts have been issued in cities in the provinces of Henan, Shandong and Liaoning.
The high-speed rail linking Shenyang, capital city of Liaoning, and the coastal city of Dalian cut its speed to 200 kilometers per hour from the usual 300 kilometers per hour, due to limited visibility.
In addition, 15 highways in Liaoning Province were either completely or partially closed.
