How come there are still typhoons in November? Experts explain super typhoon "Connie"

Who would have thought that a super typhoon would approach Zhejiang in November? According to the China Meteorological Observatory, this year's 21st typhoon "Connie" has been upgraded to a super typhoon. The possibility of "Connie" landing on the coast of Fujian and Zhejiang cannot be ruled out, and it will bring "strong winds and heavy rains" to Zhejiang in the future.

In the face of the strong wind and rain brought by "Connie", according to the "Zhejiang Province Flood Control, Typhoon Prevention and Drought Relief Emergency Plan", the Provincial Flood Control Headquarters decided to upgrade the typhoon prevention emergency response to Level III at 10:00 on October 31.

Typhoon "Connie" path probability forecast map Source: China Meteorological Observatory

As an autumn typhoon, "Connie" is not only late in coming, but also has a changeable path. Judging from the cloud map of "Connie", not only is its size still strong, but its core cloud mass is fat and solid, and the eye of the typhoon is clear, as if it is coming with ill intentions.

Why is "Connie" so strong? What impact will it have on Zhejiang? Why is there still a typhoon in November? The reporter interviewed Mao Yanjun, a senior engineer at the Zhejiang Provincial Climate Center, to explain the relevant situation.

Whether "Connie" comes or not, heavy rainfall in Zhejiang is unavoidable

According to the forecast of China Meteorological Network at 10:00 on the 31st, "Connie" will move northwestward at a speed of 25-30 kilometers per hour and will land on the coast from Taitung to Hualien in Taiwan Province around noon on the 31st (48-52 meters/second, 15-16 levels, strong typhoon level or super typhoon level).

Satellite cloud image of Typhoon Connie Source: Screenshot of China Meteorological Administration Typhoon Network website

What is a super typhoon? Xin Xin, a meteorological analyst at China Meteorological Channel, wrote that if it is still a super typhoon when it lands in Taiwan, it will break the record of the strongest typhoon to land in Taiwan in October since 1949, and it will also be the latest super typhoon to land in Taiwan. The strongest typhoons to land in Taiwan in October before were Longwang in 2005 and Rosa in 2007, both with a wind speed of 50 meters per second.
So, will "Connie" land in Zhejiang with such intensity?

"After passing Taiwan, the typhoon will gradually turn to the northeast along the coast of Zhejiang and Fujian. The possibility of landing in Zhejiang cannot be ruled out, but the intensity will tend to weaken." Mao Yanjun said, "Connie" is also "impatient". If it lands in Zhejiang, the time will be relatively short, and the overall direction should be to the northeast.

According to statistics, no typhoon has landed or brushed the coast of Fujian and Zhejiang since October 25 since 1949. It is worth noting that under the influence of "Konnie", there is a possibility of record-breaking rainfall in many places in Zhejiang. Moreover, whether "Konnie" makes a second landfall or not, there will be obvious wind and rain.

Zhejiang cumulative rainfall forecast from October 30 to November 1 Source: Zhejiang Meteorological Observatory

According to the Zhejiang weather forecast, heavy rainfall will mainly occur from the night of November 31 to November 1. Northern and eastern Zhejiang will be cloudy with heavy rain and rainstorms, some areas will have heavy rainstorms, and some areas will have extremely heavy rainstorms; other areas will be cloudy with moderate to heavy rain, and some areas will have rainstorms.

Why is the rainfall of "Connie" so strong this time? Mao Yanjun said that there are many factors that caused the increase in rainfall this time. On the one hand, the northerly airflow on the west side of the typhoon led the weak cold air down, which had a convection-stimulating effect on the typhoon, resulting in an increase in the intensity of precipitation. On the other hand, the heavy rainfall was also affected by the typhoon's path, and some terrains may have triggered heavy rainfall that was rare in the same period.

What makes the "autumn typhoon" blow until November?

In meteorology, typhoons generated from September to November are usually called autumn typhoons. Since September, several autumn typhoons have come one after another. The "typhoon factory" seems to be completing some kind of KPI and is constantly "producing" autumn typhoons.

"Usually, autumn typhoons last longer, as long as November, which is normal." Mao Yanjun said that the frequent occurrence of autumn typhoons is related to the warm sea temperature. At present, the sea temperature in the East China Sea is relatively high, and the sea temperature in the equatorial central and eastern Pacific is low in the east and high in the west, which is conducive to the formation of typhoons. In addition, global warming is also a factor. The temperature of the ocean surface provides sufficient fuel for the accumulation of typhoon energy, and the water vapor in the atmosphere provides sufficient moisture for typhoon precipitation.

Since the autumn typhoons hit November, does that mean there are winter typhoons? "Typhoons occur all year round. The typhoons that have a greater impact on my country are mainly concentrated in the first half of July to October. The probability of typhoons in other periods affecting my country is relatively small, which may lead to less attention from the public," Mao Yanjun explained.

Generally speaking, there are not many typhoons generated in winter, and even fewer land in my country. Meteorological records show that since 1949, only two winter typhoons have landed in my country, namely Typhoon Irma No. 27 in 1974, which landed in Taishan, Guangdong on December 2, and Typhoon Nanmadol in 2004, which landed in Pingtung, Taiwan on December 4.

"Typhoons generated in autumn are more powerful than those in summer and are more likely to cause serious disasters." Mao Yanjun reminded that the impact of autumn typhoons on agriculture needs more attention. It is now the autumn harvest period, and the strong winds and rainstorms brought by typhoons will damage crops. At the same time, this process has a great impact on transportation. The public should pay attention to timely understanding of travel information and try to avoid going out during the concentrated period of wind and rain.