The recent weather can be said to be hot from morning to night.
The lowest temperature in Hangzhou this morning was also nearly 30°C (29.9°C), once again setting a new record for the lowest temperature this year.
The temperature rises rapidly during the day, and has broken through the high temperature line (35°C) before 10 o'clock, and the Hangzhou Meteorological Observatory continues to issue an orange warning signal for high temperature, reminding everyone to pay attention to heat prevention and cooling.
Every time there is a high temperature in the middle of summer, a question to the meteorological department will appear: why is the weather forecast afraid to report 40°C when it is already so hot? Not long ago, some netizens used a thermometer to measure that the temperature on the ground in Hangzhou had exceeded 50 °C.
Yesterday, the maximum temperature in Yuhang District exceeded 40°C.
According to the Hangzhou Meteorological Observatory, according to the regulations of the World Meteorological Organization, the temperature released by the meteorological department is the temperature measured by the thermometer in the louver box. The louver box must be located on the lawn, 1.5 meters above the ground, and the surrounding area is relatively open, without tall buildings, trees, etc. blocking the wind or sunlight.
Why? This is because the weather station needs to be set up in a place where the terrain is flat and open, and the measured meteorological data is highly representative. The purpose of placing the thermometer in the louver box is to obtain the true state of the atmosphere, so that it is convenient to analyze the changes in air temperature, air pressure and other indicators on a larger scale, and make weather forecasts.
Obviously, due to the different reasons of the underlying surface, the temperature of asphalt roads, cement roads, and street slabs is different in the same city, especially under the strong sunlight, the temperature in these places may be much higher than in the shutter box.
In the city, it is normal for us to take out our thermometer gun and measure a temperature that is different from the weather forecast, but this is not the temperature inside the shutter box. In addition to the quality of the thermometer gun and other factors, the main reason is that the heating degree caused by buildings, roads, cars, etc. in different places in the city is different, and the heating degree is also different in different cities and different areas of the same city.
And the temperature we feel, its scientific name is somatosensory temperature. The body sense temperature focuses on "feeling", that is, the human body's feeling of cold and heat, which cannot be simply understood as the temperature of the human skin. Studies have shown that under the same temperature conditions, people will have different feelings of warmth and coldness due to differences in humidity, wind speed, solar radiation (insolation), clothing color and even mood.
A certain wind speed will blow the heat emitted by the body away from the body. Even if the temperature is high, it will feel drier. Therefore, under normal circumstances, the greater the wind speed, the lower the perceived temperature.
Under normal circumstances, cloudy days and sunny days, the temperature of human body can be 4 °C ~ 6 °C, or even greater.
When the air humidity is high, the evaporation rate of sweat is very slow, and the person has a slimy feeling, which is very uncomfortable. The "sauna days" that are often encountered in summer are the product of "high temperature + high humidity". Due to the humidity in the south of the continent, it is often hotter in the south than in the north for the same temperature.
Finally, I would like to bring you a good news for cooling: the Hangzhou Meteorological Observatory predicts that under the influence of the high-altitude trough on the 10th, the power of the subtropical high will weaken, and the showers and thunderstorms will increase, and the temperature will drop.
Zhejiang Provincial Meteorological Observatory predicts that on the 10th-13th, many places in northern Zhejiang will be cloudy to overcast, showers or thunderstorms will increase, and the high temperature will temporarily "retreat".
At the same time, we remind everyone that when there is a thunderstorm from the 10th, it can be accompanied by strong convective weather such as short-term heavy rain and 8~10 thunderstorms and strong winds, and pay attention to preventing secondary disasters that may be caused by short-term heavy precipitation and thunderstorms and gales.