The National Meteorological Center issued an orange alert for heavy fog, the second highest of the three-tier warning system, across large parts of North China on Tuesday morning. Dusty weather is expected to persist in Northwest China until Thursday.

The center said that on Tuesday, dense fog reduced visibility to less than 500 meters in parts of Hebei and Shandong provinces, and Beijing, with some areas experiencing thick fog with visibility under 200 meters.

The fog coincides with a period of poor atmospheric dispersion, bringing light to moderate haze to parts of North China, the Yellow-Huaihe River Valley, and Northeast China. Conditions are expected to improve in North China as a cold front moves in on Tuesday night. Multiple cold air activities from Wednesday through Friday are forecast to clear the haze across most of the country, the center said.

However, from March 7 through 10, parts of North China and the Yellow-Huaihe River Valley are expected to experience light to moderate haze as atmospheric dispersion conditions worsen, the center said.

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Elsewhere, the center forecast blowing dust and floating dust in most parts of Northwest China. On Wednesday and Thursday, parts of the Xinjiang Uygur autonomous region, Shaanxi, Gansu, and Qinghai provinces will experience sandy weather.