The first cold wave in Guangdong is coming. What is the cold wave？ How to defend？

From the afternoon of 15th, strong cold air will enter Guangdong from the south, and Guangdong will have its first cold wave this year.

What is the cold wave? How to form? What impact will it have? How to defend?

Xiaonan is here to answer you one by one.

Cold air with a temperature drop of more than 8℃ is a cold wave.

Cold wave refers to a weather process in which strong cold air in polar regions or high latitudes invades the middle and low latitudes on a large scale, resulting in a large-scale sharp cooling and northerly winds, sometimes accompanied by rain, snow and freezing disasters.

But not every time cold air goes south, it becomes a cold wave. According to the national standard of Cold Air Grade, a cold wave can occur when the daily minimum temperature drops by 8℃ or above within 24 hours, or by 10℃ or above within 48 hours, or by 12℃ or above within 72 hours, and the daily minimum temperature drops by 4℃ or below.

He Lifu, chief forecaster of the Central Meteorological Observatory, said that the main cause of the cold wave was guided by the northerly airflow in the mid-high latitude long wave ridge, and the cold air from the polar regions gathered in Central Siberia. As the high-altitude horizontal trough turned into a vertical trough, the strong cold air would quickly break out all the way south.

Simply understood, this cold wave is that cold air first gathers at high latitudes and then explosively moves south quickly.

The temperature in Guangdong dropped sharply by 8℃-10℃

Then, what impact will the cold air of this cold wave level have on Guangdong? The Provincial Meteorological Observatory predicts that the cold wave will affect our province from north to south on the afternoon of the 15th, with the temperature dropping sharply by 8℃-10℃, with 5-7 gale on land and 7-9 gale on the coastal sea.

Under the control of cold air, from 16th to 18th, it was mainly cloudy and the weather was cold. The lowest temperature in the process was 0℃-5℃ in the northern part of Guangdong and the northern cities and counties of the Pearl River Delta, among which it was about minus 3℃ in alpine mountainous areas, 8℃-11℃ in Zhanjiang and Maoming, and 5℃-8℃ in other cities and counties. There was low temperature and ice (frost) in mountainous areas and counties in the north-central part.

Specifically, on the 16th, most of the rain in our province turned cloudy and the weather was cold.

From 17th to 19th, most of the province was cloudy and the cold weather continued.

From 20th to 21st, most of the province was cloudy and the temperature rose day by day.

In addition, the cold wave will also bring strong winds at sea. From the night of the 15th to the 17th, there will be northerly winds of grade 7-9 in the coastal waters of our province.

In the urban area of Guangzhou, it is expected that the cold wave front will arrive in Guangzhou around the evening of the 15th. During the cold wave, the lowest temperature in central and northern Guangzhou can reach below 5℃.

Outdoor epidemic prevention duty points need to be weather-proof.

It is worth noting that this cold wave transit not only led to a sudden drop in temperature, but also merged with the warm and humid airflow in Guangdong to form strong convective weather. The meteorological department reminded that it is necessary to do a good job in the defense of sudden drop in temperature, heavy precipitation and strong winds:

1. Attention should be paid to the prevention of heavy precipitation and secondary disasters such as urban and rural waterlogging and landslides.

2. Outdoor epidemic prevention duty stations should pay attention to rain and wind protection, temporary stacking points of materials should pay attention to preventing rain soaking, and outdoor duty personnel should pay attention to rain, rain and cold protection.

3. The public should pay attention to cold and warmth to avoid respiratory diseases, fever, cough and other uncomfortable symptoms, pay attention to indoor ventilation, and be careful to prevent carbon monoxide poisoning caused by the use of gas.

4. Planting and aquaculture should also take corresponding measures to prevent the cold wave.

5. In rainy and foggy weather, the road surface is slippery, the visibility is low, and there is icing in the mountainous area of northern Guangdong in the later period, so it is necessary to pay attention to traffic safety.

6. Coastal and sea winds are strong, so attention should be paid to water traffic and production safety.

Beware of all kinds of diseases and gas poisoning

Strong winds and cool weather can easily lead to colds, tracheitis, coronary heart disease, cor pulmonale, stroke, asthma, myocardial infarction, angina pectoris, migraine and other diseases, and sometimes make the patient’s condition worse.

Keep warm: When the temperature drops suddenly, pay attention to adding clothes to keep warm, especially to keep hands and face warm.

Reinforcement: Close doors and windows and fasten outdoor structures.

Non-slip: be careful when you go out.

Disease prevention: Old and weak patients, especially people who are sensitive to temperature changes such as cardiovascular patients and asthma, should try not to go out.

Gas prevention: beware of gas poisoning, especially for families that use coal stoves for heating.

If you still think it’s too much trouble to read words? It doesn’t matter, a picture to understand the cold wave:

[Nanfang Daily reporter] Zhang Zijun Xie Qingyu

[Content Source] Provincial Meteorological Bureau China Meteorological Bureau