Hail is made up of ice, so why do hail appear in summer?

The sun bakes the earth hot in the summer, and it is easy to generate a lot of hot and humid air near the ground. Hot and humid air rises rapidly, and the temperature drops dramatically, sometimes as low as -301. The moisture in the hot air condenses into water droplets, which quickly freeze to form Xiaoice droplets.

Xiaoice beads tumble up and down in the clouds, constantly sticking and condensing the surrounding water droplets into ice, getting heavier and heavier, and finally falling from the sky, which is hail. Hail can only be produced when the hot and humid air currents rise strongly. It is estimated that its air flow must rise at a speed of more than 20 meters per second.

Hail often occurs during the summer months. In winter, the temperature near the ground is very low, and it is not possible to generate strong and rapid updrafts, so it is impossible to form hail. Hail is very harmful.

It destroys crops, destroys houses, harms people and animals. Effective means have been developed to artificially rain before hail arrives, so that hail cannot form, thus eliminating the damage caused by hail.

When hail comes, it is necessary to quickly find a safe place with a covered cover, and protect against lightning and hail nearby to prevent hail attacks; If you are outdoors, protect your head with rain gear or other alternatives, and move indoors as soon as possible to avoid humans and animals**. Hail is when water vapor condenses into clouds, liquefies when it encounters cold air, and then turns into rain or snow when it encounters lower temperatures. If the temperature drops too quickly, the condensed ice mass will be larger, called hail.

In summer, precipitation is abundant and the sunshine is hot, so the amount of water vapor is large and the updraft is strong. When the water vapor rises to a certain level, it will encounter cold, which is the temperature difference. Lower temperatures allow water vapor to form clouds and condensation nuclei, so hail may occur.

When the hail is big enough, the updraft is a little weak, and now it can't hold on, so it falls, which we call "hail". Hail mostly occurs in the summer while snow occurs in the cold winter months, the formation of hail requires a vigorous updraft movement, whereas snow does not require just water vapor rising in normal motion. The relative humidity of hail should reach 100%, while snow does not.

They also have a common feature, that is, they all need a certain temperature difference and a certain amount of condensation nuclei. Hail is more difficult to form than snow. Under the influence of the air current, the Xiaoice beads tumble up and down in the clouds, constantly sticking and condensing the surrounding water droplets into ice, getting heavier and heavier, and finally falling from the sky, which is hail.

However, in autumn and winter, the temperature is low, and the air convection capacity is not large, so it is difficult to have hail.

In summer, there are two currents of air in the sky, low pressure and high pressure, so it is easy to form hail when it hits it.

Hail occurs in summer because only the summer climate is suitable for producing hail, and there are no such strong convective weather in other seasons.

This is because hail is a type of severe convective weather, which only occurs in summer.

This is due to the fact that the climatic conditions for the formation of hail can only be met in summer.

Hail is formed by cumulonimbus clouds, and the formation of cumulonimbus clouds needs to meet three conditions: first, there must be a large amount of unstable energy to produce convective weather; second, there must be sufficient water vapor; The third is that there is enough shock, and the afternoon temperature in summer is very high, so there is often a strong air flow rising, so these conditions determine that cumulonimbus clouds can only appear in summer.

Conditions for the formation of hailstones:

1. There should be strong wind shear.

2. There must be a fairly thick layer of instability in the atmosphere.

3. Cumulonimbus clouds must develop to a temperature that can freeze individual large water droplets (generally considered to be -12 -16).

4. The vertical thickness of the cloud should not be less than 6 8 km.

5. Cumulonimbus clouds have abundant water content. Generally 3 8 grams per cubic meter, above the maximum rising velocity there is an accumulation zone of liquid supercooled water.

6. There should be an oblique, strong and uneven updraft in the cloud, generally above 10 20 m sec.

Hail is only possible during thunderstorm conditions in summer.

It is caused by the rising air flow caused by the thermal radiation of the sun.

Hail is a disease caused by air cooling and condensation in a short period of time, and gradually accumulates and expands.

In summer, when the sun bakes the earth hot, it is easy to produce a lot of hot and humid air near the ground. Hot and humid air rises rapidly and the temperature drops sharply, sometimes as low as -30. The water vapor in the hot air condenses into water droplets and quickly freezes to form Xiaoice beads.

Xiaoice beads tumble up and down in the clouds, constantly sticking and condensing the surrounding water droplets into ice, becoming heavier and heavier, and finally falling from the sky, which is hail. That's why hail only happens in summer.

Hail is formed by cumulonimbus clouds, and the formation of cumulonimbus clouds needs to meet three conditions: first, there must be a large amount of unstable energy to produce convective weather; second, there must be sufficient water vapor; The third is that there is enough impact, the temperature is very high in summer, and there is often a strong air flow rising, so these conditions determine that hail can only occur in summer, understand? ╮(

Hail is not only seen in summer, but only in summer. Hail has a strong seasonality, with warm air active in summer and cold air activity frequent, and hail is prone to occur. Hail is more common in the evening because of the strong convective effect during this time.

First of all, you have to know why hail falls in the sky, simply put, due to the low temperature in the sky, the particles suspended in the air absorb the moisture in the clouds, so that the particles continue to increase, in the process of falling, if the temperature plummets these particles become Xiaoice crystals, this Xiaoice crystals are hail.

The updraft has no way to send it back into the air before it falls to the ground, which is hail. In other seasons, the temperature is low and the air does not have much convection capacity, so hail weather generally does not occur.

First of all, the following three conditions must be met.

1. There should be a fairly thick unstable layer in the atmosphere (in fact, the clouds inside should be thick enough, and the thickness should not be less than 6 km to 8 km).

2. It needs to be a cumulonimbus cloud (there is water to form hail. ）

3. There needs to be a strong air convective movement.

I won't go into other details, there are many detailed instructions on the Internet.

Let's just say why it hails in the summer and not in the winter.

Because the winter is cold, there is not so much unstable convection, and it does not get hot and cold.

So, since there will be no strong air convection, the water in the cumulonimbus clouds will either change to rain or snow. Under normal circumstances, it does not hail.

Hail is the ice particles that fall from the sky, the ice attack block, its grains.

The diameter is generally 5-10 mm, and the largest particle size recorded in the literature can reach more than 300 mm. Hail from the sky can cause great damage to houses, people, livestock, crops, etc., and form a disaster. Hail is a product of convective weather, formed in thick and strong cumulonimbus clouds, and meteorologically said to be deep stratification without concealment.

Because the temperature is relatively high in summer, there is a lot of warm and humid air, and once a cumulonimbus cloud is formed, it is very easy to cause a strong version.

The convection, the warm and humid air on the ground, can be transported to an altitude of 8000 meters above sea level, after the warm and humid air rises to an altitude of 8000 meters above sea level, it is easier to form hail when it encounters a low temperature of minus 20, therefore, in the hot summer afternoon, when encountering cumulonimbus clouds, it is most likely to form hail, do you see what I said right?

Because when it rains, there can be no hugs, and when it doesn't rain, can there be hail on a snowy day?

Because it's hot in the summer, I wear less, so I'll play haha.

In summer, the surface water is exposed to the sun and vaporized, and then rises into the air, a lot of water vapor together, condensed into clouds, at this time the relative humidity is 100%, when it encounters cold air, it is liquefied, and the dust in the air is used as a condensation nucleus, forming raindrops or ice crystals, which is getting bigger and bigger, when the temperature drops to a certain extent, the water vapor of the air is supersaturated, so it rains, if it encounters cold air and there is no condensation nucleus, the water vapor will condense into ice or snow, that is, it will snow, if the temperature drops sharply, This will form larger ice masses, also known as hailstones.

Hail is a solid precipitation. It is a spherical or conical ice cube composed of alternating transparent and opaque layers. The diameter is generally 5 50 mm, and the largest can reach more than 10 cm, and the larger the diameter of the hail, the greater the destructive power.

Hail often destroys crops and threatens the safety of people and animals, which is a serious natural disaster, and many countries with serious hail disasters have carried out artificial hail prevention tests.

Hail comes from convective clouds (cumulonimbus) that are particularly convective. The updraft in the cloud is stronger than the general thunderstorm cloud, and the Xiaoice hail grows up and down several times in the convective cloud by the hail embryo up and down and supercooled water droplets, and when the updraft in the cloud cannot support it, it descends to the ground. Large hail occurs in thunderstorm clouds with a strong acclique updraft and a high content of liquid water.

Hail refers to solid precipitation that falls from strongly developing cumulonimbus clouds, which are solid in structure and vary in size. In meteorology, solid precipitation with a diameter of more than 5 mm is usually called hail, 2 5 mm diameter is called ice pellet, also called Xiaoice hail, and precipitation containing more liquid water and soft structure is called soft hail or graupel. Hail is also irregular in shape, mostly ellipsoidal or spherical, but cone-shaped, oblate, and irregular are also common.

In hail clouds, the air flow is very strong, usually in the direction of the cloud, and there is a very strong updraft that enters from the base of the cloud and exits the upper part of the cloud. There is also a downdraft flowing in from the middle layer behind the cloud and exiting from the base of the cloud. This is where hail usually occurs.

These two organized updrafts and downdrafts are connected with the ambient airflow, so the airflow structure in the strong hail cloud is generally more persistent. The strong updrafts not only transport sufficient moisture to the hail cloud, but also support the hail particles to stay in the cloud, allowing it to grow to a considerable size before landing.

When the surface water is exposed to the sun and vaporized, and then rises into the air, a lot of water vapor together, condensed into clouds, at this time the relative humidity is 100%, when it encounters cold air, it is liquefied, and the dust in the air is the condensation nucleus, forming raindrops (tropical rain) or ice crystals (mid-latitude rain), which is getting bigger and bigger, when the air temperature drops to a certain extent, the water vapor of the air is supersaturated, so it rains, if it encounters cold air and there is no condensation nucleus, the water vapor will condense into ice or snow, it is snow, if the temperature drops sharply, it will form a large ice mass, that is, hail.

Hail generally occurs in summer or during the spring and summer periods, when the air is very humid and prone to unstable temperatures. When the temperature is high in summer, hot air close to the ground flows upwards to form an updraft. According to the knowledge of geography in high school, it can be known:

For every 100 meters of altitude, the temperature decreases by one degree. So the temperature in the high air will be very low.

When the raindrops in the clouds meet a violent upward air flow and are carried to an altitude below 0 degrees, the small raindrops will liquefy into Xiaoice droplets. When the rising air flow is weakened, the Xiaoice beads will descend (because the Xiaoice beads are still relatively small in size and light in weight, and there are air currents to drag them down, so they will not fall to the ground); When the updraft containing water vapor increases, the Xiaoice beads rise and increase in size. When the air flow continues to increase and weaken, so that several times, the volume of small ice Xiaoice will continue to increase will become large ice blocks, when the air flow can not drag the weight of large ice blocks, it will fall to the ground, forming the hail we see.

Hail is formed in convective clouds, when the water vapor rises with the air flow and cold, it will condense into small water droplets, if the temperature continues to decrease with the increase in height, reaching below zero degrees Celsius, the water droplets will condense into ice particles, in the process of its upward movement, and will adsorb Xiaoice particles or water droplets around it and grow, until its weight can not be carried by the updraft, that is, it will fall, when it falls to a higher temperature zone, its surface will melt into water, and at the same time it will also absorb the surrounding small water droplets, at this time, if it encounters a strong updraft and is lifted again, Its surface condenses into ice, and so on and so on, like a snowball, its volume grows larger and larger, until its weight is greater than the sum of the lift of the air flow and the buoyancy of the air, that is, it falls downward, and if it reaches the ground, it does not melt into water and is still a solid ice particle, which is called hail.

Because the weather is colder in winter, hail is not easy to form, the weather is hotter in summer, there is a lot of water vapor in the air, the hot sun shines on the earth, the air near the ground is roasted and rises, but it is blocked by the cold air in the high air and cannot go up the air above is cold, the air below is hot, the cold air and hot air push each other, very stable, resulting in a cumulonimbus cloud containing hail, the hail in the cloud keeps moving up and down with the convection, other snowflakes and Xiaoice crystals stick to the hail, making the hail bigger and bigger, and the updraft in summer is very strong, Hold these hailstones and prevent them from falling, the temperature at high altitude is below zero degrees Celsius even in midsummer, so the hail will not melt, and it will not fall until the hail is large enough to reach a certain extent, and the updraft will not fall until it can support them, and the weather in winter is cold and dry like frost, it is difficult to form cumulonimbus clouds, and the updraft is not strong, and the ice crystals will fall before they become hail, so it is not very good to hail in winter. Hail is as small as a grain of rice and as big as an egg, so the formation of hail is affected by the season.