China News Service, Hangzhou, July 26 (Zhang Yuhuan, Wei Yanran, Xu Shuying) In two days, "fireworks" went down to Zhejiang twice-after landing in Putuo District, Zhoushan City, Zhejiang Province around 12:30 on the 25th, this year Typhoon No. 6 "Fireworks" made landfall twice on the coast of Pinghu, Zhejiang at around 9:50 on the 26th. It also became the only typhoon that landed in Zhejiang twice since there are meteorological records.
Why did "fireworks" land in Zhejiang for the second time, why they "stayed" before and after landing, and what impact will it bring afterwards... The reporter interviewed Xu SpaceD, chief forecaster of the Zhejiang Meteorological Observatory on the above issues, and revealed the typhoon "Duo" The reasons for “change” and “slow heat”.
Why does the "firework" path "dodge"?
According to the Zhejiang Meteorological Observatory, starting from the 22nd, the outer cloud system of Typhoon "Fireworks" began to affect Zhejiang Province for 5 days.
Although the typhoon has moved out of Zhejiang and entered Jiangsu, the impact is still ongoing.
Xu SpaceD said that the location of its landing point has also become the focus of the meteorological department's tracking.
However, due to the fact that its path is changeable, it is extremely difficult to forecast.
He explained that during the typhoon "Fireworks" event, the atmospheric circulation was complicated, and it coexisted and interacted with the three typhoons "Chapaca" and "Nibert". At the same time, the subtropical high pressure was northward, leading to weaker airflow, resulting in "fireworks". Almost relying on its own "internal force" to move forward slowly.
This has also caused the typhoon "fireworks" to change its moving path, out of a "variable" path such as moving north, falling south, turning west, and stagnating.
Zhejiang Meteorological Department strengthened research and judgment.
Photo by Zhang Yudi
As for the "second landing" is actually not a rare situation in the meteorological record. Most typhoons are affected by the topography of China, and after landing along the coast, they will go north. For example, they will first land in Zhejiang and then land in Shandong, Liaoning and other places. common.
However, Xu SpaceD said frankly that Jiaxing, which is "embedded" in Hangzhou Bay, is actually not easy to become a typhoon landing site compared to Ningbo, Zhoushan, Wenzhou and other coastal cities in Zhejiang.
It also became the first typhoon to land in Jiaxing since the weather record.
When will the "fireworks" stop the heavy rain?
"'Firework' not only moved very slowly when it first spawned, but the movement speed is still very slow during this time." Xu SpaceD said that typhoon "Firework" is undoubtedly a "chronic", and it has been stranded on the island since it landed on Zhoushan on the 25th. 5 hours, and then stayed in Hangzhou Bay for up to 11 hours.
The longer the residence time, the greater the impact of wind and rain.
Affected by the "fireworks", there have been torrential rains in Ningbo, Shaoxing, Zhoushan, Taizhou, Jiaxing and other places in Zhejiang Province for several days.
From 8 o'clock on the 22nd to 6 o'clock on the 26th, the average rainfall in Zhejiang Province was 134 millimeters, and the accumulated rainfall in 150 towns (streets) exceeded 300 millimeters, and the accumulated rainfall in 31 towns (streets) exceeded 500 millimeters.
Xu SpaceD said that the reason for the higher rainfall is that the "train effect" brought by the typhoon is more obvious, that is, the long-term precipitation is not caused by a stable rain cloud cluster, but many precipitation cloud clusters have passed through the same. In one place, just as different carriages of a train pass through the same railroad track one after another, causing long-term precipitation in the same area.
"As the typhoon moves further north, significant precipitation will be produced in northern Zhejiang, Anhui and other places. At the same time, as the continuous water vapor in the Pacific is added to the fireworks, it may continue to affect northward with the intensity of a tropical storm." Xu spaceD said.
Zhoushan, Zhejiang before the typhoon made landfall.
Photo by Huang Ling Yi
"Wind disaster" is more difficult to prevent than "rain disaster"?
Another feature of "fireworks" is the huge "power" of the gale it brings.
Affected by the typhoon, large-scale persistent gales have appeared in the coastal waters and eastern regions of Zhejiang in the past few days. Among them, strong winds of magnitude 15 or higher have occurred in Xipu and Niluoshan in Jiaojiang District.
As of 6 o'clock on the 26th, strong winds above level 10 along the coast of northern Zhejiang have lasted for 40 hours, while the previous typhoon "Lichma" caused strong winds above level 12 to last for 20 hours.
Xu SpaceD introduced that the so-called "wind disaster" of typhoons is more difficult to prevent than "rain disasters" because the previous heavy rainfall was not continuous, and the impact of strong winds is wider, which will have certain impacts on agricultural greenhouses, industrial plants, etc. .
Coastal areas have had some experience in dealing with strong winds before, but for inland areas, all aspects of wind protection preparations may be improved accordingly.
According to the Zhejiang Meteorological Observatory, it is expected that the "fireworks" will move to the northwest at a speed of about 10 kilometers per hour, and their intensity will gradually weaken.
On the 27th, there were still heavy rains and heavy rains in Huzhou, Jiaxing, northern Hangzhou and other places.
On the 28th, there were moderate to heavy rains and local torrential rains in parts of northwestern Zhejiang.
The Meteorological Department reminded that due to the impact of "fireworks", the accumulated rainfall in Ningbo, Shaoxing, Zhejiang and other places was particularly heavy. Heavy rainfall was still in some areas of northern Zhejiang on the 27th, causing high risks of urban and rural waterlogging, geological disasters and other derivative disasters, and further prevention is needed.
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