How does thunder and lightning occur on a rainy day?

People usually call the clouds where lightning occurs thunderstorm clouds, in fact, there are several kinds of clouds that are related to lightning, such as stratocumulus clouds, Nimbostratus clouds, cumulonimbus clouds, cumulonimbus clouds, and the most important thing is cumulonimbus clouds.

The formation of clouds is the process of condensation of water vapor in the air to a saturated or supersaturated state for various reasons. Saturation of water vapour in the air is a necessary condition for the formation of clouds, and the main ways of this are:

The water vapor content remains unchanged, and the air cools down;

The temperature does not change, and the water vapor content increases;

It not only increases the water vapor content, but also lowers the temperature.

But for cloud formation, the cooling process is the most important process. In the process of cooling, the cooling effect caused by the upward movement is the most common.

A cumulonimbus cloud is a type of cloud that forms during a strong vertical convection. Because the ground absorbs much more radiant heat from the sun than the air layer, so the ground temperature rises more during the day, and this warming is more obvious in summer, so the temperature of the atmosphere near the ground also rises due to heat conduction and heat radiation, and the gas temperature will inevitably expand, the density will decrease, and the pressure will also decrease, according to the principle of mechanics, it will rise, and the density of the air layer above will be relatively large, and it will sink. During the uplift, the hot air expands and lowers the pressure, and at the same time exchanges heat with the high-altitude and low-temperature air, so the water vapor in the rising air mass condenses and fog droplets appear, forming clouds.

During strong convection, the fog droplets in the clouds further cool down and become supercooled water droplets, ice crystals, or snowflakes, which gradually increase with altitude. At the freezing altitude (-10 degrees Celsius), the release of latent heat due to the massive freezing of supercooled water causes the cloud top to suddenly develop upwards and spread horizontally near the tropopause to form anvils, which is a distinctive feature of cumulonimbus clouds.

During the formation of cumulonimbus clouds, positive and negative charges accumulate in different parts of the cloud under the simultaneous action of the atmospheric electric field, the electrostatic effect of temperature difference and the electroelectric effect of fragmentation. When the charge accumulates to a certain extent, it will discharge between clouds or between clouds and ground, which is commonly referred to as lightning.

Thunder and lightning are generally generated in cumulonimbus clouds with strong convection, so they are often accompanied by strong gusts of wind and heavy rain, and sometimes hail and tornadoes. The upper part of the cloud is dominated by a positive charge, and the lower part is dominated by a negative charge. As a result, a potential difference is formed between the upper and lower parts of the cloud.

When the potential difference reaches a certain level, an electric discharge occurs.

Thunder is a phenomenon of electrical discharge between clouds with a different charge or between clouds and the earth, and when it rains, the clouds in the sky have either positive poles and negative poles. When two clouds collide, lightning is emitted, and at the same time, a lot of heat is released, which heats and expands the surrounding air. The air that is heated and expanded in an instant will push the surrounding air, causing a strong **-type vibration.

This is thunder.

Thunder occurs on rainy days, how is thunder generated?

In rainy days, it is often accompanied by thunder, and thunder is actually a discharge phenomenon, which is caused by violent friction in the process of movement of the atmosphere. At the same time, when thunder is hit, it will be accompanied by lightning and thunder, and the clouds that often occur lightning are mainly called thunderstorm clouds, and other lightning related to stratocumulus clouds, cumulus clouds and cumulonimbus clouds.

The main reason for the occurrence of lightning and thunder is that the moist air rises during rain, and the water droplets on the ground are broken under the strong convection of the air, resulting in a large number of electric charges in the clouds, and because the distribution of such charges is very complex, the clouds have positive and negative charges.

And they are distributed in different regions at the same time, and in the case of such a polar distribution, a potential difference is formed. When this potential difference reaches a certain level, an electric discharge is generated, resulting in the lightning that we are all familiar with, and it is usually accompanied by natural phenomena such as strong gusts of wind and heavy rain.

And in this kind of case, because the cloud with charge and the ground protrusions in contact, will produce a fierce discharge phenomenon, so there will often be a very obvious roar in the place of discharge, which is the thunder that we usually hear, which is called "thunder" a natural phenomenon, but also in accordance with this principle, there are lightning rods on many high-rise buildings, which can make the objects at high places not easily damaged by lightning strikes.

Knowing the above reasons, we can also analyze and know the reasons why there is generally no thunder in winter, mainly because it does not have the conditions for thunder, first of all, there is rarely a rising air flow in winter, so the charge cannot be generated in the clouds, and the current with the charge difference cannot be formed. Secondly, the air humidity in winter is not high, and a series of conditions for the generation of thunder cannot be reached in the absence of moisture, which is also the reason why thunder is more likely to occur in hot weather than in cold weather.

Lightning is a natural discharge phenomenon. In summer, there are many clouds in the high sky that are constantly moving, and the clouds are staggered and rubbing against each other, thus generating a large number of electric charges and forming an electric field. Since the same charge repels each other, the positive and negative charges are concentrated at each end of the cloud.

When the electricity carried by the cumulus cloud reaches a certain level, it will pass through the air and discharge, neutralizing the two charges and generating sparks. This is the phenomenon of lightning. Because of the uneven resistance of the air, the shape of the electric advance is mostly zigzag, forming a band of light like a tree branch, which is called lightning.

And the discharge causes the air to vibrate and make a sound, which is thunder.

The main reason is that there are a lot of electrons in the air, and then when it rains, there will be collisions, so thunder will appear.

Thunder is caused by the collision of water molecules in the dark clouds in the sky, which forms thunder and lightning.

Because thunder is a necessary condition for rain, it can make the air rise, thus guaranteeing moisture in the air. Ions in the atmosphere are unevenly distributed in rainwater, resulting in the phenomenon of thunder and lightning.

It is that there is some friction between the clouds, and there is some movement between the particles, so that there will be some discharge phenomena, and thunder and lightning will be formed.

There are a lot of positive and negative ions in the atmosphere, and the raindrops will carry some electric charges, so the phenomenon of discharge will occur.

People often encounter lightning in their daily life, the voltage of lightning is very high, the current is more than 30,000 times that of ordinary current, and it may reach more than 300,000 times in serious cases. Then some people are curious, if a person is hit by lightning, what will happen to the body? Today I will talk to you about this problem, I think if a person is struck by lightning, there are mainly several physical changes:

First, the harm of lightning strikes is similar to electric shock, but it is faster and more serious, first of all, I want to tell you that if people are struck by lightning, the first situation is that the lightning is extremely powerful, and then it hits the head, then the body may immediately turn into ashes. Even if the body is not reduced to ashes, the person may have died.

Second, a person struck by lightning, whether dead or alive, the blow inflicted by lightning on the human body is enough to make the person lose consciousness at the moment of being struck by lightning, and the unconscious person certainly has no feeling.

Three, if you are struck by lightning, you can still survive, and after a short period of unconsciousness, you will be confused. Wait until you are fully conscious. He felt the electrical burning sensation in his body, a little blackened, his limbs stiffened, and maybe even his organs were disabled.

The damage of lightning strikes to people is mainly electrical burns and electric injuries, and lightning exists for a short time and has a large area of action. Unlike ordinary man-made electrical strikes, the burns caused are less severe, and if there is a metal substance on the surface of the injured person, the body may be burned by high temperatures. It will form red or rose-colored, branch-like or dovetail-like markings on the **, which is called lightning strike marking.

No matter what kind of lightning strikes you, or dies or injure, it's certainly not a nice feeling. Therefore, we should pay special attention in our lives, especially when it rains and thunders, it is best not to play with mobile phones or use other electrical appliances. Especially in rural areas.

The lightning protection measures are not complete, and accidents are very easy. In addition to the several physical changes I mentioned above, do you have any other ideas, welcome everyone to follow me and leave a message to discuss.

The rain in the sky comes from the clouds in the sky, and the clouds in the sky are actually condensates of water, which come from the evaporation of water vapor from the ground. When the water droplets in the cloud reach a certain level, that is, they cannot be supported by the rising air current, the water droplets (which may also be ice drops, snowflakes) will fall to the ground, which is what we see as rain (hail, snow).

Evaporation of water vapor can occur at any time, but not rain all the time. In the air, when the temperature is high, the amount of water vapor that can be held is large, and when the temperature is low, the amount of water vapor that can be held in the air is less. When the air moves from high temperature to low temperature, the water vapor will change from unsaturated to supersaturated, and then the water vapor will condense into water droplets, and when the weight of the water droplets exceeds the buoyancy of the air, rain will fall.

For example, in the afternoon of summer, due to the strong water vapor evaporation, rise, condensation, and form showers; Frontal rain formed by the southward movement of cold air and the hot and humid air flow from the southeast, and so on.

As rivers, rivers, lakes, and seas are exposed to the sun, water becomes water vapor. The water vapor rises and turns into small water droplets or Xiaoice crystals, and the air flow below is constantly transporting the water vapor to the clouds. The small water droplets and Xiaoice crystals in the cloud collide with each other in motion, and the volume will increase.

The water droplets in the lower layer of the cloud slowly get larger, and as the volume of the ice crystals in the upper layer of the cloud increases, the water droplets fall between the droplets in the lower part of the cloud, and the water droplets become larger and larger. When these droplets are so big that the updrafts can't hold them back, it rains.

In summer, lightning and thunder are common natural phenomena. Do you know what lightning is all about? It is the static electricity generated when the clouds moving high in the air rub against each other, and when the static electricity accumulates in large quantities, it discharges each other, thus forming the lightning that we see cutting through the sky.

Thunder is actually the vibration that occurs when lightning strikes through the air.

A lightning bolt is usually hundreds to thousands of meters long, so the time it takes for the sound of the lightning to reach our ears when it penetrates the air will be a few seconds or more than a dozen seconds (the speed of sound in the air is 340 m s). In addition, thunder is reflected back and forth between clouds, so when a lightning bolt passes, we hear thunder, and the thunder "rumbles" for a long time.

Clouds are rubbingly charged in the air, when negatively charged clouds are in close proximity to positively charged clouds. Discharge. That's why thunder and lightning are formed.

Sometimes it doesn't thunder and it rains.

Thunderstorms are severe weather phenomena produced by extremely unstable air conditions, often accompanied by strong winds, heavy rain, lightning, lightning strikes, and even hail or tornadoes, so they can often cause disasters.

Thunderstorms can be broadly divided into two categories, one is a frontal thunderstorm and the other is an air mass thunderstorm. It starts to increase every year in March and reaches its peak in January; Thereinto.

3 Most of the thunderstorms in June are frontal thunderstorms, and in July and September, most of them are air mass thunderstorms.

The birth of a thunderstorm:

The life span of a single thundercloud (i.e. cumulonimbus) is very short, usually only one or two hours, and can be divided into three stages: development, maturity and dissipation (Figure 11). In the first stage, an updraft is formed, which sends warm, moist air into the air. When the rising air cools, the water vapor begins to condense and turn into clouds.

As the air continues to rise, the clouds accumulate higher and higher, reaching the colder altitudes. The water droplets in the clouds become larger and heavier. Some freeze into snow or hail, while others grow larger and larger until they can no longer be supported by the updraft.

A downdraft that comes with or precedes the rain will cause cool gusts of wind, which means that a thunderstorm is coming.

The cause of the static electricity generated in thunderclouds by the turbulent air currents is not fully understood, and may be partly due to the friction and decomposition of water droplets. The positive charge is at the upper end of the cloud, while the negative charge attracts the positive charge on the ground below. The air acts as an insulator between the clouds and the ground, which for a short time prevents the electropole charges from finding an equilibrium current from passing through.

Lightning occurs when the voltage formed by the charge at the poles is so large that it can break through the insulating air. (In some heavy thunderstorms, the electrostatic voltage can reach several million volts.) Lightning can occur in clouds, between two clouds, or from the top down, or between the clouds and the ground from the bottom up.

Worldwide, the average number of lightning strikes the Earth is about a hundred times per second.

Most lightning bolts are two in a row. The first blow is called the leading blitz, which is an invisible stream of charged air.

Lead, straight down to near the ground. This stream of charged air acts like a wire, creating a path for the second strike current. As soon as the lead approaches the ground, a return strike electric current jumps up along the lead, and then there is visible lightning and audible thunder, which is the second blow.

This response current has an electric core, and there is a circle of hot air like a tube around it to trap it, and this layer of hot air will glow, expand and **, that is, thunder. **Lightning is seen almost immediately when it happens, but thunder always comes later, due to the speed of the sound (about per second.

340 meters) is slower than the speed of light (300,000 kilometers per second).

Lightning equalizes the unbalanced electric potential in a thundercloud cloud. Similarly, the downdraft caused by rainfall equalizes the temperature of hot and cold air. When the ground cools down, the hot air does not rise, so the weather often clears up quickly after a brief thunderstorm in summer.