The Formation Process of Typhoon 96 15

(2) In early September, the monsoon trough east of the Philippines became active again, and deep convection continued to erupt. At this time, the subtropical high is strongly extending westward, and the ridge line falls to 27° n in the south, firmly controlling the south China coast. The classic situation of this typhoon heading west in South China is not uncommon. On September 2nd, JTWC naturally escalated into a tropical storm near Guam. As a newborn, she didn't grow fast, but she grew up in the midnight snack, and it took her two days to integrate a complete LLCC. With the help of high-altitude anticyclone, the divergence is good. JTWC issued a tropical cyclone formation warning (TCFA). On the morning of September 5th, JTWC was upgraded and tropical depression 23W was born. After 18 hours, JTWC upgraded to a tropical storm. After four days of development, it finally has a name: Sally, a gentle and beautiful name. Before 2000, China Meteorological Bureau only called typhoons by year+number. The name Sally may not be known, but the number 96 15 is frightening. In fact, Sally is not as "gentle" as her name suggests, but a real "woman". Good divergence, weak wind shear and very good water temperature. Half a day after the name, she strengthened from a tropical storm to a first-class typhoon. The subtropical high is stable. She is moving to the west-northwest direction, trying to break into bashi channel and go straight to Guangdong. Yes, there is still no typhoon landing in Guangdong. (3) After nearly half a month's rest, the water temperature east of the Philippines is high and red. Sally didn't mean to be tired. She continued to sprint to the top, and the energy kept gathering towards the center. The organization of CDO is getting closer and closer, and convection is constantly erupting. Finally, her eyes opened and the CDO was embedded more and more clearly. On the evening of September 7th, Sally Jia broke out in the cloudless, clear and round eye of Wan Li on the northern coast of Luzon Island. At the same time, her eye wall also has good convection. JTWC analyzed the strength of T7.0, and immediately gave the evaluation of 140kts, the highest level of category 5 typhoon! HKO set the intensity at 95 kilometers, which is the upper limit of today's strong typhoon. The relatively conservative evaluations of JMA and CWB are 85kts and 48 m/s, and the most puzzling is CMA, which only gives the strength of 40m/s960hPa. In fact, the actual measurement of landing is far more than that. At this time, Sally Jia was close to Luzon Island, and it was inevitable to be disturbed by the terrain, and the pace of enhancement finally came to an end. Similarly, due to the influence of topography, Sally Jia crossed the Strait almost due west, and the eye of the wind crossed the Balintang Islands. I can't imagine how miserable these backward islands are under the five-level typhoon eye wall. It was not until more than ten years later that these islands built weather stations one after another. Without actual measurement, we will never know what Sally Jiafeng is. As far as people know, there is only a gust of 34.8m/s and an evergreen gust of 26.9m/s in Lan Yu, Taiwan Province, 200km away. These records are neither painful nor itchy. Without the support of actual measurement, people can only rely on satellite images. In China in 1996, Fengyun-2 geostationary satellite has not been launched, and Fengyun-1 experimental stars are dead, so we can only rely on foreign satellite data. 1996, before entering the information age, it is not easy for the meteorological bureau. There is only one terrible fact in front of us: a super typhoon is passing through bashi channel and will attack Guangdong head-on! (4) People finally realized that the newcomers were not good, and HKO also realized the threat of Sally Jia, so it issued the No.1 warning signal at 5 am on September 8, when Sally Jia had just entered the 800-kilometer warning line in Hong Kong. The sun rises slowly, the sun shines on the earth, the gentle north wind blows gently, and the air is filled with sultry breath. During the day of September 8, high temperature weather generally appeared in South China, and Taiwan mother spread from the southeast. Anyone familiar with typhoons knows that this is a sign that a typhoon is coming. They guessed the beginning, but they didn't expect the typhoon to come so fast and so fierce ... The subtropical high was firmly pressed over South China, and Sally Jia took a fast northwest-west path, with an average moving speed of 32km/h in 24 hours and the fastest moving speed exceeding 40 km/h, which was equal to the typhoon "Hope" of 1979. On the evening of the 8th, in just 12 hours, Sally Jia ran 500 kilometers, broke into 1 16E, and entered an area less than 400 kilometers southeast of Hong Kong. Guangdong Meteorological Observatory issued typhoon warning on 17 as usual. HKO also issued the No.3 strong wind signal, indicating that "it is very unlikely to issue the No.8 tropical cyclone warning signal". Facts have proved that HKO is wrong. At dusk, the last ray of sunshine disappears in the sky, and then it will be a sleepless night. After nightfall in ........................., the northeast wind is still fresh and the air seems a little stuffy. No one knows when the wind will strengthen, so we can only wait quietly. At 20 o'clock, Sally Jia drifted 290 kilometers to the southeast of Hong Kong, and Sally Jia's tiny 6-level wind circle with only 250 kilometers still did not touch the ground. At 2 1, the wind increased slightly, and strong winds appeared in offshore islands, but the peaceful atmosphere on land remained unchanged. This may be the last calm before the storm comes. At 2200 hours, the strong wind finally came. The fast moving speed intensifies the semicircle effect, and Sally Jia's dangerous semicircle covers the whole coast of South China. Hong Kong, located in the eastern part of the Pearl River Delta, bears the brunt. It was drizzling, and the wind force in Henglan Island increased from 1 0 m/s to 17.5 m/s within1h, which was close to level 8. Seeing that the situation was not good, the Macao Meteorological Bureau quickly changed the signal of No.8 northeast typhoon, but HKO remained silent. As Sally approached step by step, an increasingly strong northeast wind mixed with dense raindrops violently hit the land of South Guangdong. At 23: 00, the wind power in Henglan Island was further strengthened, and stopped falling after jumping to 25m/s! In addition, the sustained wind speed in all parts of Hong Kong has generally risen above the strong wind level, and strong winds and even heavy rains have blown from offshore and highland, making Victoria Harbour in jeopardy. HKO is still hesitating. At 2: 00 am on the 9th, Sally Jia passed at180km south of Hong Kong. Now, Hong Kong will face Sally's most powerful northeast quadrant. Lightning flies in the air like a ribbon, and thunderstorms wake up one house after another. Violent southeast winds rushed into Victoria Harbour, causing waves of frenzy. Water increase of 0.8 ~ 1.3m generally occurs in Hong Kong, and the maximum gust in Hong Kong (except in mountainous areas) is recorded in Henglan Island-140 km/h, with the magnitude of 13, Changzhou. HKO had no choice but to "reissue" one at two o'clock on 15, which was the only typhoon signal No.8 on 1996. As Sally left quickly, the storm in Hong Kong gradually subsided, and HKO lowered the No.8 southeast gale or storm signal at 5: 40. The typhoon signal No.8 of 3 hours and 25 minutes is the shortest since 1984. At dawn, the wage earners go to work as usual, and the student brother has an extra day of sunshine holiday. Sally Jia left Hong Kong, except for the rain 30 ~ 80 mm away, which was the mess after the strong wind, with branches and debris everywhere. This is just a gift from Sally. (5) In September, the cold air in the north is ready to move. Just as the typhoon was making waves at sea, a cold air quietly spread to the south of the Yangtze River and entered Guangdong on the morning of the 9th. This undoubtedly strengthened the power of "storm tide" for Sally. Under the great pressure gradient, there were 8 ~ 12 gale successively along the coast from Hong Kong to Yangjiang, and the gust was 10 ~ 15, among which the gust of Shangchuan Island was 38m/s, that of zhapo in Yangjiang was > 40m/s, and that of Yangjiang was 47m/s. Maoming and Zhanjiang in front were in danger. At 8 o'clock on the 9th, Typhoon 96 15 entered the sea just south of Yangjiang. Guangdong Meteorological Observatory issued a typhoon emergency warning to Zhanjiang, predicting that Sally Jia is likely to land near Zhanjiang. For Zhanjiang people, typhoons are a common occurrence, and many people have landed in Zhanjiang. This morning, life is still going on, and people are lucky to hope that the typhoon will leave. They didn't know that this was a strong typhoon with winds as high as 50m/s, and seemed to believe that typhoons 8007 and 54 13 would never come again. The whole city of Zhanjiang is neck and neck, almost in an unguarded state: typhoon warnings are not issued in place, typhoon prevention measures are not implemented, people do not receive the latest typhoon news, schools continue to attend classes, people continue to go to work, and people continue to March on the streets. Some fishermen at sea have not returned to Hong Kong, the operators of oil beds at sea have not been evacuated, and the people on the fishing rafts are still guarding their blood and sweat ... As early as the night before yesterday, Zhanjiang Port has changed to hang the No.3 typhoon signal (level 8). The typhoon prevention headquarters will call the relevant units one by one in the afternoon to report the emergency typhoon prevention. Some units are not only unattended, but even did not start typhoon prevention work on the eve of typhoon landing. They thought that the typhoon would not land until the next night, and it was not too late to do typhoon prevention work the next morning. The responsible leader of a company said disapprovingly that the captain would naturally leave the dock when the wind was strong. The situation in Zhanjiang Port is also not optimistic. Due to the large number of crew and limited anchorage, the port has reached the state of supersaturation. Merchant ships, fishing boats, ferries, military vessels and all kinds of small boats, regardless of foreign ports in Hong Kong, have flooded into these waters. Once anchored, it will trigger a terrible chain reaction with disastrous consequences. The typhoon is less than 120km away from Zhanjiang. The gale circle has covered the west coast of Guangdong, and the eye wall is approaching step by step. At this time in Zhanjiang, the sky was more gloomy, Ma Yun was flying all over the sky, and the northeast wind of 7 ~ 8 was mixed with drizzle, which sounded the last alarm for Zhanjiang people in the dark. Fortunately, many people realize that the situation is not good. Some schools arranged for students to go home in time without receiving the notice of suspension. People in the street hid one by one, waiting quietly in the increasingly heavy rain. (6) At 9: 30, Sally's eyes began to touch the trembling Zhanjiang, and the nightmare came: the wind swallowed everything, the rain covered the sky, and garbage fragments flew all over the sky. The motorcycle overturned instantly, the car lost control and the traffic was paralyzed. On weekdays, the seemingly upright tree fell down instantly, and the giant billboard floated in the air like a paper owl in a child's hand. In Zhanjiang Port, the giant gantry crane weighing dozens of tons was as fragile as a toy, broke, damaged and slipped into the sea ... At this time, the atmosphere of Zhanjiang Meteorological Observatory was extremely tense, and the tense nerves of meteorologists were constantly refreshed. The data was shocked. At that time, the weather station was still in the old city, and the instruments were far less advanced than today. Use Dyne's self-recording anemometer. The principle is to use a board suspended in the air to record the rising angle of the board when the wind blows, and the error can be imagined. Moreover, the upper limit of the wind speed on paper is 50 m/s, and the old air pressure recorder used in the same year has a measuring range of only 960hPa- 1050hPa. Under such a powerful typhoon as 96 15, such a low-end instrument is simply not enough to record her rage. The wind stations along the eastern coast of Zhanjiang were basically destroyed, and the instruments of the meteorological observatory barely maintained their work. Every time there is a gust of wind, the pointer of the anemometer suddenly jumps up, and finally the wind force is no longer lower than 12. From 10: 00 to 10: 37, the wind speed exceeded 40m/s 9 times, the maximum average wind speed was 48.8m/s in 10 minute, and three strong gusts above 57m/s were recorded. Because the wind speed is too high, the tip of the anemometer is blown away from the wind recording paper by the wind pressure, which exceeds the observation limit and fails to record the actual maximum wind speed and extreme gust-at least the continuous wind is certain >; 50 m/s, gust > 57 m/s. 1 1 around, the strong typhoon 96 15 landed in the coastal area of Wuyang town, Wuchuan city, Zhanjiang! The first typhoon that landed in Guangdong this year is also the latest typhoon since the founding of the People's Republic of China. Yes, the eye of the wind is coming. During the period of11:00 ~1:12, the wind speed dropped to the minimum, stood still for 5 minutes, and then increased. As for the air pressure, it is 993. 1hPa at 08: 00, 953.5hPa at 10: 34, and 942.3hPa at 10: 56 (when the north wind is blowing1kloc-0/m/s). It is speculated that typhoon 96 15 is closest to Zhanjiang Station at around 1 10, and the pressure drops 1 7 HPA in the first half hour. Zhanjiang Meteorological Observatory finally revised the minimum pressure to below 938.9hPa, and the maximum wind speed was 6/kloc-0 measured by Nanhai 503 ship. Wuyang Town, Wuchuan City, 30 kilometers away from the landing site, there was no meteorological station in that year, and the maximum wind speed could not be elegant. It is worth noting that Zhanjiang is located in the west and south of the typhoon path, that is, in a safe semicircle. According to the moving speed of 96 15, which is nearly 40km/h, the wind force in the dangerous half circle can even reach more than 55 m/s, and the wind direction is southerly. As the saying goes, "Go back to the south and cross the north". In fact, after 96 15 passed the nearest point, Zhanjiang city was completely in a safe semicircle, and the wind was not stronger than before the typhoon landed. The wind direction quickly reversed to northwest wind-west wind-southwest wind. Although the strong wind in the west is not as strong as the wind blowing to the shore in the east, the sudden change of wind direction makes the force on the object change dramatically, and the originally solid object quickly loses its support. The original safe place was exposed to the strong wind without reservation. The power supply and water supply in Zhanjiang city collapsed completely, and the whole town was in chaos ... The hidden worry of the port finally became a reality. According to the custom, some ships throw a splayed anchor with a long left and a short right, and want to wait until the wind is strong before releasing the right anchor chain. This method is effective if it is in the right semicircle (dangerous semicircle) of typhoon. Zhanjiang port is located in the left half of the typhoon. When the ship turns left counterclockwise with the wind, the anchor chain is unbalanced, so it breaks down. There was a chain reaction in crowded waters, and the ships collided head-to-tail and were damaged by a chain collision, and finally sank. The gale above 13 lasts for 40 minutes, above 12 lasts for 48 minutes, and the gale above magnitude 8 lasts for 7 hours. 96 15 came and went in a hurry. A few hours later, she landed again in Beihai and Fangchenggang, Guangxi. When she landed in Beihai, the air pressure was only above 960 hectopascals, but she was still able to prove her strength with a gust of more than 40m/s, making her one of the best typhoons in the history of Beihai, Guangxi. The king always says goodbye. 1 days later, 96 15 disappeared in the mountains on the Sino-Vietnamese border. (7) With the distance of 96 15, the strong wind has receded, but the rain continues. One day on September 9, the precipitation reached 80 ~ 150 mm, and the road was full of water and garbage. A large number of big trees were stripped of their leaves, branches and bark, and finally became pillars and fell to the ground! The strong wind blew the lamppost to the ground, Bai Wan. Numerous houses collapsed, and many buildings became empty shells with only reinforced concrete. There are countless damaged houses. Among them, the huge Zhanjiang Gymnasium was later rebuilt at a cost of tens of millions of yuan. Homeless people can only take refuge in temporary shelters and cry in the wind and rain. The scenery by the sea is terrible. The strong wind set off a storm surge of 1 ~ 2 meters, and most coastal areas in western Guangdong exceeded the warning water level. Nearly one-third of the ships in the harbor broke down and crashed, and 100-ton ships were thrown into the Shanghai levee by the wind and waves. The fishing boat sank, and the fishermen on board were uncertain. 97 bodies were found in the harbor. When the seawall burst, fish ponds, shrimp ponds, paddy fields and farmland were completely submerged, forming an indistinguishable boundary. Bananas and sugar cane are not upright. What is even more unbearable is the social order after the typhoon. Neglected wells have become the source of life-saving, candles and oil lamps are in short supply, and many black-hearted shopkeepers drive up prices and repeatedly ban them. When people are in panic, rumors are everywhere. Late at night, someone spread rumors about the earthquake. Like frightened birds, the citizens packed their bags in a hurry and fled to the open area in the suburbs, regardless of the night and power failure. The horror scene of emergency escape was staged in the city, as if the war years were coming again. Finally, people stopped at the suburban market two kilometers away, stayed for more than three hours, and got the nerve to go home. The whole city of Zhanjiang suffered heavy casualties. Witnesses recalled: "I will never forget those parents who were killed in the typhoon because they picked up their children." "Many people were killed and injured by rotating furniture because they couldn't hold the doors and windows in the house; Many pedestrians on the road were killed by blown objects and were injured everywhere. " At that time, the hospital was full of wounded people, and the medical suture was used up in a short time. "According to official statistics, 330 people were killed and 8.73 million people were affected. During the typhoon, houses collapsed or damaged 1 164000, the agricultural disaster area was 444000 hectares, and the direct economic loss was 2 1863 million yuan. Among them, 256 people were killed and 23,000 injured in Zhanjiang alone. Zhanjiang has suffered unprecedented destruction. For the first time in the world, the gantry crane was blown into the sea by the wind, and 55 large machinery in Zhanjiang Port were damaged or destroyed. The wires and towers of Zhanjiang power grid were all destroyed and disconnected from the provincial power grid. Communication lines and optical cables are all interrupted. Water supply and transportation were completely paralyzed, and the whole city was cut off from electricity, water, work and classes. Typhoon washed away seawall135.3km, bridges and culverts 168, crops 2 18400 hectares, grain loss19100t, and 3996 shipwrecks. (8) According to the measured data, 96 15 is undoubtedly the strongest typhoon that landed in Guangdong since records began. The late sky chart may not exceed the record of 96 15. The destructive power of typhoon 96 15 far exceeded the defense standards of facilities and people's understanding level of that era, and it may not be digested even today. We must learn several lessons today. First of all, typhoon information must be released quickly and accurately. For a typhoon with a stable path like 96 15, it is not enough to know the landing point only. People make mistakes in judging the landing time with their usual thinking, which delays the typhoon prevention work and causes losses. Typhoon information must be timely and accurately transmitted to the relevant units. What's more, the atmosphere is changing rapidly, and the difference between the two predictions may be very large. Even in today's developed information media, information is inevitably backward. Secondly, we must popularize the awareness of disaster prevention and implement disaster prevention measures. If the intensive 96 15 landing is a natural disaster, then carelessness and luck are man-made disasters. Port dredging and facility inspection is a long-term task to ensure the safety when disasters come. The defense measures expressly stipulated must be implemented, and the prevention of the defense and the withdrawal of the withdrawal must obey the command. Third, natural disasters must be protected with high enough standards. At present, extreme weather events are becoming more and more frequent, and no one can guarantee when a super typhoon like 96 15 will make a comeback. Not being satisfied doesn't mean not being satisfied. On the premise of reasonable investment, take high standard protection as far as possible to ensure the safety rate of the project within its service life. Human society will always make progress. Under the premise that extreme events are inevitable, disasters will remain in history forever if we deal with them correctly and reasonably.