Why was the sky red before the typhoon? Is the sky red because a typhoon is coming?

Lead: Typhoon is terrible, but as long as we can take effective measures to deal with it, we can minimize its harm. Typhoon scenery is also a must. For example, sometimes the sky is red before a typhoon. Then, do you know why the sky was red before the typhoon came? The sky is red. Is a typhoon coming?

Why was the sky red before the typhoon?

Because when a typhoon comes, the cloud density in the sky changes, just like white light illuminating a prism, the seven colors will be separated, and the red is below. The red light has the smallest deflection. After the seven colors are separated, the red light shines more on the surface and above the earth, so it looks like the sky is red.

When the typhoon came, it was from southeast to northwest. That is to say, in the evening before the typhoon, when the sun sets, the sunset just dyed the clouds brought by the typhoon in the southeast. So the night before the typhoon is always red. There is a proverb that says: Sunset clouds are all over the sky, either sunny or stormy.

Before the arrival of the typhoon, the general meteorological department will issue accurate forecasts, so we can pay attention to the meteorological cloud pictures and understand the direction and arrival position of the typhoon. Usually, two days before the arrival of the typhoon 1-2, the weather visibility improved obviously, and a large area of cirrocumulus appeared in the sky (white without shadow, in the form of thin waves, small balls or fish-scale clouds). If the weather is fine, there will be a flaming cloud, so be prepared in advance.

Causality between clouds and weather

China is located in Asia and is often influenced by the southeast monsoon from the Pacific Ocean and the southwest monsoon from the Indian Ocean. In spring and summer, the monsoon from the ocean carries a lot of water vapor. When clouds appear, it shows that there are not only a lot of water vapor in the air, but also enough dust particles and clouds, which are important conditions for the formation of rain.

Why does the morning glow mean rainy day and the evening glow mean sunny day?

Sunglow is formed when the sun rises. Clouds with dust and water vapor have enough time to blow inland from the coast. As the terrain rises, the temperature drops, the air convection is intense, the air pressure is unstable, and the combination of water vapor and dust is easy to condense into water droplets and fall into the rain.

Sunset is formed when the sun goes down. Clouds and water vapor have floated over the local area, so there will be no severe air convection and the air pressure is relatively stable. The next day, it is likely to be sunny.

Introduction of typhoon warning signal

Typhoon warning signals are divided into five levels, which are represented by white, blue, yellow, orange and red respectively.

First, the typhoon white warning signal

Meaning: Affected by typhoon within 48 hours.

Defense guide:

1, enter the state of typhoon concern and be alert to the impact of typhoon on the local area.

2, pay attention to understand the latest situation of typhoon through meteorological information dissemination channels.

Second, the typhoon blue warning signal

Meaning: it will be affected by typhoon within 24 hours, with an average wind force of 6 or above or a gust of 8 or above; Or have been affected by the typhoon, the average wind force is 6 ~ 7, or the gust is 8 ~ 9 and will continue.

Defense guide:

1, enter the typhoon alert state and prepare for typhoon prevention; .

2. Pay attention to the latest news of typhoon and the notice of the government and relevant departments to defend against typhoon.

3. Strengthen temporary structures such as closed doors and windows, board houses, iron houses and scaffolding, and properly arrange outdoor shelving and hanging objects.

4. Personnel engaged in mariculture and offshore operations should be evacuated in time, and ships should return to Hong Kong in time to take shelter from the wind or take other shelter measures.

Third, the typhoon yellow warning signal

Meaning: Affected by typhoon within 24 hours, the average wind force is above 8 or gust10; Or have been affected by the typhoon, the average wind force is 8 ~ 9, or the gust 10 ~ 1 1 will continue.

Defense guide:

1, enter the typhoon windproof state, and pay close attention to the latest news of typhoon and the typhoon defense notice issued by the government and relevant departments.

2. Primary and secondary schools, kindergartens and nurseries should be closed, and students who have not left school need not go to school; Students on their way to and from school should go to a safe place nearby or go home under safe conditions; Under the premise of ensuring safety, schools should properly arrange students (including school buses and boarding houses) and arrange for students to go home from school.

3. Residents should close doors and windows, properly arrange outdoor shelves and hanging objects, and try to avoid going out. People in dangerous areas and dangerous houses should be evacuated in time to ensure that they stay in a safe place.

4. Stop outdoor collective activities and high-altitude outdoor work.

5. Close beaches, scenic spots, parks and playgrounds in a timely manner, close relevant areas, and organize personnel to avoid risks.

6. Personnel engaged in mariculture and offshore operations should be evacuated. Ships returning to Hong Kong to take shelter from the wind are not allowed to leave Hong Kong without authorization, and defensive measures should be taken.

7. Relevant emergency departments and rescue units should strengthen their duty, pay attention to the disaster situation in real time, and implement countermeasures.

Fourth, the typhoon orange warning signal

Meaning: it will be affected by typhoon within 12 hours, with the average wind force above 10 or gust above 12; Or have been affected by the typhoon, the average wind force 10 ~ 1 1, or gust 12 will continue.

Defense guide:

1, enter the state of typhoon emergency defense, pay close attention to the latest news of typhoon and the typhoon defense notice issued by the government and relevant departments.

2 primary and secondary schools, kindergartens and nurseries are closed, and schools should properly arrange boarders.

Residents should avoid going out and make sure to stay in a safe place.

4. Stop large-scale indoor assembly and evacuate people immediately.

5. Beaches, scenic spots, parks and playgrounds should be closed, and personnel should be quickly organized to avoid risks.

6. Strengthen port facilities; Ships should take defensive measures to prevent anchoring, grounding and collision.

7. Relevant emergency departments and rescue units should closely monitor the disaster situation and do a good job in emergency rescue and disaster relief.

Verb (abbreviation for verb) Typhoon red warning signal

Meaning: It will be or has been affected by the typhoon within 12 hours, and the average wind power can reach above 12, or it has reached above 12 and continues.

Defense guide:

1, enter the typhoon emergency windproof state, pay close attention to the latest news of typhoon and the typhoon prevention notice issued by the government and relevant departments.

2 primary and secondary schools, kindergartens and nurseries are closed, and schools should properly arrange boarders; It is suggested that employers stop work (except for special industries) to provide safe shelter for stranded personnel.

Residents should not go out and make sure to stay in a safe place.

4. When the typhoon center passes by, the wind will decrease or stay still for a period of time, so be vigilant and defensive to prevent the strong wind from attacking again after the typhoon center passes by.

5. Relevant emergency departments and rescue units should closely monitor the disaster situation and do a good job in emergency rescue and disaster relief.