What is hail? Why is there hail?

Hail is a dangerous phenomenon that occurs all over the world. In our country, hail is mainly in mountainous areas or areas bordering the sea or mountains. So what is hail? Why is there hail? Let’s find out more details with Tnhelearning.edu.vn through the following article!

What is hail?

Rainwater condenses into rocks, ice cubes of various sizes, shapes and falls are called hail. This phenomenon is affected by thunderstorm clouds, extremely strong cold fronts that come quickly. The size of the hail is about 5mm to tens of centimeters.

Hail occurs for about 5 – 30 minutes and usually falls with showers. The phenomenon usually occurs in mountainous areas or areas bordering the sea or mountains, even in the rainy season or summer. In the northern region of our country, hail often occurs, mainly in March – May.

Why is there hail?

When the air currents are convective or in other words, the air flows up continuously, hail will form. Typically the months change between the cold season to the hot season or vice versa.

If the temperature in the clouds is colder – 20 degrees Celsius, the water vapor in the clouds will form small ice particles and fall. Small ice particles falling to meet the lower cloud layer turn into water droplets with a temperature below 0 degrees Celsius.

The air currents are constantly rising, bringing a large volume of cold water droplets to the upper layers of the cloud. They freeze with the existing ice particles in the upper layer, making the volume of the ice particles larger and larger, when the weight increases to a certain extent they will fall low.

When the hail falls on the low cloud layer, it will be covered with an additional layer of water film and subjected to the impact of rising air. At some point, the air currents can no longer hold the hail and will fall to the ground and form hail.

Types of hail

Hail has a variety of different sizes and shapes, but in general, hail has two main forms as follows:

• Ice granules : Also known as small hail, usually spherical, conical with a diameter of about 5mm.
• Ice granules : Partially or completely transparent or opaque in appearance. Irregular, conical and spherical in shape with diameters ranging from 5 – 50mm, falling from clouds, may fall sporadically, or form an irregular curtain.

Most hail particles will have a falling speed of about 30 – 60m/s, even up to 90m/s. Therefore, they are extremely dangerous and harmful to humans, animals and plants.

Why does hail only appear in the hot season?

Hail mainly occurs in the hot and humid season and in intense heat. Especially the months of April, May, June and 9, 10, and November . This is the period of change of seasons between cold to hot and vice versa. When convection currents take place strongly, hail will form.

The water content in the air often increases in the hot, humid season. The lower atmosphere heats up by receiving a lot of heat, thereby forming a hot upper column of cold air. At that time, the phenomenon of air convection took place strongly, the cloud accumulated too much water and caused hail.

Signs of imminent hail

Hail is a phenomenon that is difficult to predict with weather forecasts because it is an abnormal development of hot and cold air currents. You can identify hail occurring by the following signs:

• The cloud is shaped like a darkened breast.
• Strong winds and thunderstorms with constant buzzing and rumbling sounds.
• The air temperature dropped sharply.
• The sound of rain falling on the roof was loud.

Effects of hail on life

Hail occurs causing danger, great damage to property, human life as well as animals and plants:

• For humans : Severe can lead to death because of the mass of the hail which is large and falls at a fast rate. Even, hail also punctured corrugated iron roofs, collapsed houses, damaged vehicles, and affected construction works. In addition, hail also makes the road slippery, causing traffic accidents, affecting people’s lives.
• For animals : Animals die in mass due to the unbearable cold air and falling hail.
• For plants : The crops and fruits will be crushed, broken, broken branches, unable to grow well. Soil is affected by cold air, making it difficult for plants to grow and multiply, thereby unbalanced vegetation.

How to avoid and minimize the harmful effects of hail

To minimize the harm to people and property caused by hail, you need to take reasonable precautions as follows:

• For plants and fruits : You should build a strong roof to protect them, helping to limit the impact when hail falls.
• Roof : Regularly check and reinforce the roof. In places where hail often occurs, you should use a roof with good impact resistance, soundproofing, … and make the roof slope down on both sides. This will reduce the impact force and cause less damage.

• Check the house : You check the roof frame structure, purlins are solid and carefully reinforced. If you are not sure, you often rebuild to improve and ensure the safety of your home.
• Other measures : If the hailstorm is large and lasts for a long time, you can hide under the table, bed, find hard objects to cover your head, … to avoid human damage.
• Check water quality : In hail contains a quantity of toxins that are harmful to human health. You should check the water quality before using or using a water purifier to ensure safety and avoid skin allergies.

Hopefully the above article will help you understand more what hail is and have reasonable avoidance. Any questions please leave a comment below!