The formation process of Typhoon No. 9615

(2) In early September, the monsoon trough east of the Philippines became active again, and deep convection continued to break out. At this time, the subtropical high is extending powerfully to the west, with the ridgeline falling to 27N in the south, firmly controlling the South China coast. This classic situation of westbound typhoons in South China is commonplace for people. On September 2, JTWC naturally upgraded a tropical disturbance near Guam. She did not grow rapidly when she was born. The convection waxed and waned day by day, and it took 2 days to integrate a complete LLCC. With the help of high-altitude anticyclone, the divergence is good. JTWC issued a Tropical Cyclone Formation Alert (TCFA). On the morning of September 5, JTWC was upgraded to a tropical storm, and Tropical Depression 23W was born. 18 hours later, JTWC was upgraded to a tropical storm. After 4 days of development, it finally got a name: Sally, a gentle and beautiful name. Before 2000, the China Meteorological Administration only used year numbers to call typhoons. No one may know the name Sally, but the number 9615 is scary. In fact, Sally is not as "gentle" as her name suggests, but a real "lady's man". With good divergence, weak wind shear, and very good water temperature, it intensified from a tropical storm to a Category 1 typhoon half a day after it was named. The vice high is very stable. She is heading west-northwest, trying to break into the Bashi Channel and head towards Guangdong. Yes, there is still no typhoon landing in Guangdong. (3) After nearly half a month of rest, the water temperature in the east of the Philippines is relatively high and it is red. Sally showed no sign of getting tired and continued to sprint towards the top. Energy continued to gather towards the center. The CDO's organization became more and more compact, and convection continued to explode. Finally, her eye opened and became more and more clearly embedded in the CDO. On the evening of September 7, Sally erupted as a cloudless, clear and round eye offshore of northern Luzon. At the same time, her eyewall also has good convection. JTWC analyzed the intensity of T7.0 and immediately gave an evaluation of 140kts, the highest level of Category 5 typhoon! HKO set the intensity at 95kts, which is the upper limit of a strong typhoon today. The relatively conservative evaluations of JMA and CWB are 85kts and 48m/s. The most puzzling thing is that CMA only gives an intensity of 40m/s960hPa. In fact, the actual landing test is much more than that. At this time, Sally was already approaching Luzon Island, and was inevitably disturbed by the terrain. The pace of strengthening finally came to an end. Also affected by the terrain, Sally passed through the strait almost due west, with the eye of the storm crossing the Balintang Islands. I can't imagine how miserable these backward islands must be under the eye of a Category 5 typhoon. It was not until more than ten years later that weather stations were gradually built on these islands. Without actual testing, we will never know what Sally's peak is like. As far as people know, only Orchid Island in Taiwan, 200 kilometers away, has a gust of 34.8m/s, and Hengchun has a gust of 26.9m/s. These are indifferent records. Without the support of actual measurements, people can only rely on satellite images. But in China in 1996, the Fengyun-2 geostationary satellite had not yet been launched, and the two test satellites of Fengyun-1 had long since expired, and they could only rely on foreign satellite data. In 1996, before entering the information age, it was not easy for the Meteorological Bureau. There is only one terrifying fact before our eyes: a super typhoon is passing through the Bashi Channel and will hit Guangdong head-on! (4) People finally realized that the visitor was evil, and HKO also realized the threat of Sally, so it sent out the No. 1 alert signal at 5 a.m. on September 8, not long after Sally entered Hong Kong’s 800km cordon. The sun rises slowly, shining on the earth. The gentle northerly wind blows gently, and the air is filled with a sultry atmosphere. During the day on September 8, high temperature weather generally occurred in South China, and Taimu spread from the southeast.

People who are familiar with typhoons know that this is a sign of the coming typhoon. They guessed the beginning, but they did not expect that the typhoon came so quickly and violently... The subtropical high was pressing firmly over South China, and Sally took a rapid west-northwest direction. Along its path, the average 24-hour moving speed reached 32km/h, with the fastest speed exceeding 40km/h. It is as famous as Typhoon Hope in 1979, becoming the fastest typhoon to cross the South China Sea on record! On the evening of the 8th, in just 12 hours, Sally ran 500 kilometers, broke into 116E, and entered a range of less than 400 kilometers southeast of Hong Kong. The Guangdong Meteorological Observatory issued a typhoon warning at 17:00 as usual. HKO also issued a strong wind signal No. 3, stating that "there is little chance of issuing a tropical cyclone warning signal No. 8." It turns out HKO was wrong. The last ray of sunshine at dusk disappears in the sky full of Taimu, and what follows will be a sleepless night. ………… After night falls, the northeast wind is still fresh and the air seems a little muggy. No one knows at which minute the wind will increase, so they can only wait quietly. At 20 o'clock, Sally drifted into a place 290km southeast of Hong Kong. Sally's small Category 6 wind circle of only 250km still did not touch the land. At 21 o'clock, the wind strengthened slightly, and strong winds appeared on the offshore islands, but the peaceful atmosphere on the land was still not broken. This may be the last calm before the storm. At 22 o'clock, the strong wind finally came. The rapid movement speed intensified the semicircle effect, and Sally's dangerous semicircle covered the entire South China coast. Hong Kong, located in the eastern part of the Pearl River Delta, is the first to be affected. The drizzle fell one after another, and the wind force on Henlan Island increased from 10m/s to 17.5m/s within an hour, approaching level 8. Seeing that the situation was not good, the Macau Meteorological Bureau quickly changed the northeasterly wind signal No. 8, but HKO remained silent. As Sally approached step by step, the stronger and stronger northeasterly wind mixed with dense raindrops pounced hard on the land of southern Guangdong. At 23:00, the wind force on Henlan Island further strengthened, jumping to 25m/s and then no longer falling! In addition, sustained wind speeds in various parts of Hong Kong have generally risen above the strong wind level, with strong winds and even storm winds blowing offshore and in the highlands, putting Victoria Harbor in danger. HKO is still hesitating. At 2 a.m. on the 9th, Sally passed 180km south of Hong Kong. Now, Hong Kong has to face the Northeast Quadrant, where Sally is most powerful. Lightning danced in the air like ribbons, thunderstorms woke up one household after another, and the violent southeast wind rushed into Victoria Harbor, stirring up waves of madness. Hong Kong generally experienced an increase of 0.8 to 1.3 meters of water, and Waglan Island recorded a The largest wind gust in Hong Kong (except mountainous areas) - 140km/h, level 13. Cheung Chau recorded a one-hour average wind speed of 88km/h, close to level 10. HKO had no choice but to "replace" one at 2:15, which was also the only No. 8 typhoon signal in 1996. As Sally quickly moved away, the wind and rain in Hong Kong gradually subsided, and HKO canceled the Southeast Gale or Storm Signal No. 8 at 5:40. The 3 hours and 25 minutes of Typhoon Signal No. 8 was the shortest since 1984. At dawn, the wage earners go to work as usual, while the students get an extra day of sunshine. What Sally left for Hong Kong, apart from 30 to 80 mm of rain, was the mess after the strong wind, with branches and debris everywhere. This is just a greeting gift from Sally. (5) As September enters, the cold air in the north is about to move. While the typhoon was making waves at sea, a cold air quietly spread to the Jiangnan area and entered Guangdong on the morning of the 9th. This undoubtedly enhanced the power of "storm and tide" for Sally. Under the greater pressure gradient, strong winds of magnitude 8 to 12 and gusts of magnitude 10 to 15 appeared successively along the coast from Hong Kong to Yangjiang. Among them, the gusts on Shangchuan Island were 38m/s, Yangjiang Zhapo gt;40m/s, and Yangjiang 47m/s. s. Maoming and Zhanjiang ahead are at stake. At 8 a.m. on the 9th, Typhoon 9615 entered 112E, on the sea directly south of Yangjiang. The Guangdong Meteorological Observatory issued a typhoon emergency warning for the Zhanjiang area, predicting that Sally is very likely to make landfall near Zhanjiang. For people in Zhanjiang, typhoons are common, and there are not a few that land in Zhanjiang.

This morning, life was still going on. People were hoping that the typhoon would go away. They had no idea that what was about to land was a strong typhoon with winds of up to 50m/s. They seemed to wishfully believe that the super typhoons No. 8007 and 5413 would never come again. The entire city of Zhanjiang is in a state of almost no defense: typhoon warnings are not issued in place, typhoon prevention measures are not implemented, and people cannot receive the latest typhoon news. Schools continue to have classes, people continue to go to work, and continue to take to the streets. The fishermen at sea have not yet returned to the port, the oil bed workers at sea have not withdrawn, and the people on the fishing rafts are still guarding their hard work... As early as the night before, Zhanjiang Port had changed to No. 3 typhoon signal (8 class). The Typhoon Prevention Headquarters has been calling relevant units one by one since the afternoon to notify them of emergency typhoon prevention. Not only did some units have no one on duty, they did not even start typhoon prevention work the night before the typhoon made landfall. They believed that the typhoon did not land until the next night and it was not too late to do typhoon prevention work the next morning. A responsible leader of a company said disapprovingly. , when the wind is strong, the captain will naturally leave the dock. The situation in Zhanjiang Port is not optimistic. Due to the large number of crew members and limited anchorage, the port has reached oversaturation. Merchant ships, fishing boats, ferries, military ships and all kinds of small boats crowded into this water area regardless of the local port or outer port. Once the anchor breaks, it will trigger a terrible chain reaction with disastrous consequences. The typhoon is less than 120km away from Zhanjiang. The gale circle has already covered the coast of western Guangdong, and the eye wall is approaching step by step. At this time, in Zhanjiang, the sky was getting darker, horse clouds were flying all over the sky, and the northeast wind of level 7 to 8 mixed with drizzle sounded the final alarm bell for the people of Zhanjiang who were kept in the dark. We should be fortunate that many people realize that the situation is not good. Some schools promptly arranged for students to go home without receiving notice of class suspension. People on the street took shelter one after another, waiting calmly in the increasing wind and rain. (Six) At 9:30, the walls of Sally's eyes began to touch the trembling Zhanjiang, and a nightmare came: the sound of wind swallowed everything, raindrops blocked the sky and the sun, and garbage was flying all over the sky. The motorcycle was overturned in an instant, the car lost control, and traffic was paralyzed. The big trees that seemed to be standing on weekdays suddenly fell down, and the giant billboards actually floated in the air like paper kites in the hands of children. In the Zhanjiang Port, a giant gantry crane weighing dozens of tons was as fragile as a toy, broken, damaged, and slipped into the sea... At this time, the atmosphere at the Zhanjiang Meteorological Observatory was extremely tense, and the tense nerves of the meteorological workers were repeatedly interrupted. Shocked by the refreshed data. At that time, the weather station was still in the old city, and the instrument was far less advanced than today. It used a dyne self-recording anemometer. The principle was to use a plate suspended in the air to record the angle of the plate rising when the wind blew, and then converted it into Wind speed, the error can be imagined, and the upper limit of wind speed paper is 50m/s. Similarly, the old barometric pressure recording instrument used at that time had a measuring range of only 960hPa-1050hPa. Under a powerful typhoon like 9615, such low-end instruments are simply not enough to record her fury. All anemometers along the eastern coast of Zhanjiang were basically destroyed, and the meteorological observatory's instruments could barely keep working. Every time a strong wind came, the anemometer needle jumped up suddenly, and finally the wind force was no longer lower than level 12. From 10:00 to 10:37, the wind speed exceeded 40m/s 9 times, the maximum 10-minute average wind speed was measured at 48.8m/s, and strong gusts above 57m/s were recorded 3 times. Because the wind speed was too high, the pen tip of the anemometer was pressed out of the wind recording paper, exceeding the observation limit, and the actual maximum wind speed and maximum gust were not recorded - at least it is certain that the sustained wind >50m/s and the gust >t; 57m/s. Around 11 o'clock, strong typhoon No. 9615 made landfall along the coast of Wuyang Town, Wuchuan City, Zhanjiang! The first typhoon to make landfall in Guangdong this year is also the latest typhoon since the founding of the People's Republic of China. Yes, the eye of the storm is coming. From 11:00 to 11:12, the wind speed dropped to the lowest, with calm winds for 5 minutes, and then the wind increased again.

As for the air pressure, it was 993.1hPa at 08:00, 953.5hPa at 10:34, and 942.3hPa at 10:56 (the north wind was blowing at 11m/s at this time, and the typhoon center had not yet reached the closest distance). It dropped by 47.6hPa in 3 hours. Then it exceeded the lower limit of the pressure self-recording instrument for 43 minutes! According to speculation, Typhoon No. 9615 was closest to Zhanjiang Station at around 11:10. In the previous hour, the pressure dropped by a maximum of 17hPa for half an hour. The Zhanjiang Meteorological Observatory finally revised the minimum pressure to below 938.9hPa. At the same time, the Nanhai 503 ship on the sea surface of Potou Nanyou Port measured a maximum wind speed of 61m/s, and the Binhai 283 ship measured a maximum wind speed of 65~68m/s; the Taiwan Yirong merchant ship in Zhanjiang Port measured a maximum wind speed of 65~65m/s. Maximum wind speed of 70m/s. At the landing point 30 kilometers away in Wuyang Town, Wuchuan City, there was no meteorological observation station and the maximum wind speed could not be studied. It is worth noting that the urban area of ??Zhanjiang is on the west and south sides of the typhoon's path, that is, within a safe half circle. Based on the moving speed of 9615 of nearly 40km/h, the wind force in the dangerous half circle can even reach more than 55m/s. The wind direction is returning to the south. As the saying goes, "Go back to the south and cross to the north." In fact, when 9615 passed the closest point, the urban area of ??Zhanjiang was completely within a safe half circle, and the wind was no stronger than before the typhoon made landfall. The wind direction quickly reversed to northwest-west-southwest wind. Although the strong westward wind was not as strong as the eastward onshore wind, the sharp change in wind direction caused the force on the object to change drastically, and the original solid object quickly lost its support. The once safe place was unreservedly exposed to the strong wind. The power supply and water supply in Zhanjiang City completely collapsed, and the town fell into chaos... The hidden worries in the port finally became a reality. Some ships follow the habit of throwing a figure-eight anchor with a long left and short right, hoping to wait until the wind gets stronger before letting in a longer right anchor chain. This method is effective if you are in the right half circle of the typhoon (dangerous half circle). However, Zhanjiang Port is located in the left half of the typhoon. When the ship turned left counterclockwise and downwind, the anchor chain broke due to unbalanced stress. A chain reaction occurred in the crowded waters. The ships collided nose to tail, were damaged in a series of collisions, and finally sank. The strong winds above level 13 lasted for 40 minutes, the strong winds above level 12 lasted for 1 hour and 48 minutes, and the strong winds above level 8 lasted for 7 hours. 9615 It comes in a hurry and goes in a hurry. A few hours later, she made landfall again in Beihai, Guangxi and Fangchenggang. When it landed in the Beihai, the air pressure was only over 960 hPa, but she was still able to prove her strength with gusts of more than 40m/s, making her one of the most powerful typhoons in the history of Beihai, Guangxi. A king always has to say goodbye. One day later, 9615 disappeared heroically in the mountains on the Sino-Vietnamese border. (7) As 9615 moved away, the strong winds receded, but the rain continued. On September 9, the precipitation reached 80 to 150 mm. The roads are filled with stagnant water and garbage. A large number of big trees were stripped of their leaves, branches and bark, and eventually became pillars and fell to the ground! The lamppost was bent by the strong wind and fell to the ground. Countless houses collapsed, and many buildings were reduced to bare shells of steel and concrete. There are countless damaged houses. Among them, the huge Zhanjiang Gymnasium was later renovated with tens of millions of yuan. The homeless people could only seek shelter in temporary residences, crying bitterly in the wind and rain. The scene at the beach is terrible. The strong winds set off a storm surge of 1 to 2 meters, and most areas along the coast of western Guangdong exceeded the warning water level. Nearly one-third of the ships in the port broke anchor and were damaged by collisions. The 100-ton ship was thrown onto the seawall by wind and waves. The fishing boat sank, the lives of the fishermen on board were uncertain, and 97 bodies were recovered from the harbor. The seawall burst, and fish ponds, shrimp ponds, paddy fields, and farmland were completely submerged, making it impossible to distinguish the boundaries. Neither banana nor sugar cane stands upright. What is even more unbearable is the social order after the typhoon. The neglected wells have become a source of life-saving, candles and oil lamps are in short supply, and many unscrupulous shopkeepers are driving up prices, repeatedly prohibiting them. When people are in panic, rumors spread. Late at night, someone spread rumors about an earthquake. Like frightened birds, citizens packed their bags in a hurry and fled to open areas on the outskirts of the city in a panic, regardless of the late night or power outage. Horrifying scenes of emergency escapes were staged in the city, as if the war era had returned.

Finally, people stopped at a suburban market two kilometers away. After more than three hours of silence, the brave ones went home. The entire Zhanjiang City suffered heavy casualties. Witnesses recalled: “I will never forget those parents who unfortunately died in the typhoon while picking up their children.” “Many people were beaten to death and injured by the rotating furniture in the house because they could not hold up the doors and windows; Many pedestrians were beaten to death by blown objects, and injuries could be seen everywhere. "The hospital was full of wounded people, and all the medical sutures were used up in a very short time." According to official statistics, the death toll in the province was 330, and the number of people affected by the disaster was 330. 8.73 million people. During the typhoon disaster, 1.164 million houses collapsed or were damaged, the agricultural area affected was 444,000 hectares, and the direct economic loss was 21.863 billion yuan. Among them, 256 people died and 23,000 were injured in Zhanjiang City alone. Zhanjiang suffered unprecedented devastating damage. For the first time in the world, a gantry crane was blown into the sea by the wind, and 55 large-scale machinery in Zhanjiang Port were damaged or destroyed. The wires and towers of the Zhanjiang power grid were completely destroyed and disconnected from the provincial power grid. All communication lines and optical cables were interrupted. The water supply and transportation were also completely paralyzed, and the city suffered devastating damage due to power outages, water outages, work suspensions, and school suspensions. The typhoon destroyed 135.3 kilometers of river and sea embankments, 168 bridges and culverts, damaged crops in an area of ??218,400 hectares, damaged 191,000 tons of grain, and sunk 3,996 ships. (8) In terms of actual measured figures, 9615 is undoubtedly the strongest typhoon to land in Guangdong since records began. The subsequent Lepus may not be able to exceed the record of 9615. The destructive power of Typhoon No. 9615 far exceeded the facility defense standards and people's level of understanding of that era. Even today, it may not be able to withstand it. There are several lessons that must be learned today. First, typhoon information must be released quickly and accurately. For a typhoon with a stable path like 9615, it is far from enough to only know the landing point. People use their usual thinking to make mistakes in determining the landing time, which delays typhoon prevention work and causes losses. Typhoon information must be communicated to relevant units in a timely and accurate manner. What's more, the atmosphere changes rapidly, and the difference between the two forecasts may be very large. Even today with the development of information media, information will inevitably lag behind. Secondly, awareness of disaster prevention must be popularized and disaster prevention measures must be implemented. If 9615's extremely powerful landing is a natural disaster, then carelessness and luck are man-made disasters. Port dredging and facility inspection are long-term tasks that ensure safety when disaster strikes. The clearly stated defensive measures must be implemented, defend where necessary, withdraw where necessary, and obey orders. Thirdly, protection against natural disasters must be carried out to a high enough standard. Extreme weather events are becoming more and more frequent nowadays, and no one can guarantee when a super typhoon like 9615 will come again. Just because it has not been encountered does not mean that it will not be encountered. On the premise of reasonable investment, high-standard protection should be adopted as much as possible to ensure the safety rate of the project within its service life. Human society will always make continuous progress. Under the premise that extreme events are unavoidable, with correct and reasonable responses, disasters will remain in the annals of history forever.