(On the morning of January 10th, there was foggy weather in downtown Changsha. Correspondent photo)
Hunan Daily All-Media Reporter Xiao Xiufen Correspondent Lin Cheng
At 6 o’clock on January 10, the Provincial Meteorological Observatory continued to issue a yellow warning of heavy fog. This morning, heavy fog appeared in 13 cities and States in Hunan, and there were strong fog in some areas. The visibility was less than 200 meters.
For two consecutive days, there have been different degrees of foggy weather in many places in our province. What is the reason behind the foggy weather? How long will this weather last? Hunan Daily reporter interviewed Tang Minghui, chief forecaster of the Provincial Meteorological Observatory.
"At present, the fog in Hunan is mainly radiation fog." Tang Minghui introduced that fog refers to a visible aggregate of a large number of tiny water droplets (or ice crystals) suspended in the atmosphere close to the ground. There are mainly two kinds of radiation fog and advection fog, and radiation fog mostly appears in the clear autumn and winter night or early morning when the wind is weak, and the fog will dissipate 1 to 3 hours after sunrise or after the wind is strengthened.
Why is foggy weather frequent recently? Tang Minghui explained that due to the frequent change of sunny and rainy days in our province recently, especially after it turns sunny, the temperature near the ground drops, and the water vapor content in the air exceeds the saturated water vapor, the excess water vapor will condense out and form small water droplets or ice crystals suspended in the air, which reduces visibility and forms fog. He predicted that fog would still appear in parts of western Hunan and northern Hunan on the morning of the 12th and 13th.
Meteorologists reminded that it is now in the season of frequent fog, and it mostly happens in the evening or the next morning when the rain stops and clears after cold air. Everyone should pay attention to the weather forecast in advance and plan their trip reasonably.