At 11:00 a.m. on January 19, the Henan Meteorological Observatory hung a blue warning of blizzard at the provincial level, pointing out that from 20:00 on January 20 to 08:00 on January 22, the snowfall north of the Yellow River and Sanmenxia, Luoyang, Zhengzhou, Kaifeng, Pingdingshan, Xuchang, Luohe and Nanyang will reach more than 5 mm, while some counties and cities in the western part of Shangqiu, Zhoukou and Zhumadian cities may also have more than 5 mm of snowfall, reminding Henan Province that it needs to be guarded against.
At this time, there are also many Henan netizens who are confused: Blizzard warning has been issued, where is Blizzard? Why didn't I even see a snow child? Do 5mm snow also need to be warned of blizzards? Wasn't it a huge blizzard that had snowed 5 centimeters before? Today's heavy snow warning in Henan is indeed a little ahead of schedule – supercomputer predictions suggest that widespread rain and snow are about to begin, but that snowfall in Henan Province may not start until the evening of January 20 from the west.
On the morning of January 21, the snow in the western part of Henan Province began to push eastward, and the snow in many parts of central and northern Henan will also officially begin, so for many cities, the real snow may not start until January 21, it can be said that today's blizzard warning is about two days in advance, which is relatively rare.
But this early warning also shows the difference between this snowfall - because of the abundant water vapor, the amount of snow in Henan is indeed not small. Although it seems that the forecast is more than 5 mm in multiple places, this is the amount of snowfall, that is, the amount of snow that turns into water, which is not equal to the amount of snow. Because the snow is more fluffy, the amount of snowfall and snow is like corn and popcorn, snow can be 3-20 times the amount of snowfall, in other words, 5 mm of snowfall can create 10 cm deep snow, not to mention that there is wind-blown snow, terrain accumulation and other factors, snow can be piled deeper. At present, the forecast of the Central Meteorological Observatory has also pointed out that from January 21 to January 22, Henan will likely become the center of snowfall in the north, with moderate to heavy snow in the province, and some areas can reach the level of blizzard.
The supercomputer's forecast pointed out that because the snow and water vapor is relatively sufficient, the snow in many parts of Henan will fall for a long time, and by the morning of January 24, the snow depth in many places in Henan Province will reach more than 10 centimeters, which does bring adverse possibilities to production and life, so the Henan Meteorological Observatory issued a blue warning of blizzard at the same time, but also issued a yellow warning of road ice.