How to see the weather and know whether it will rain?

From clouds, we can see the characteristics and classification of weather clouds. Clouds are visible suspensions formed by condensation of water vapor, supercooled water droplets, ice crystals or their mixtures in the atmosphere. The formation, shape characteristics, quantity, distribution and evolution of clouds not only reflect the movement, stability and water vapor status of the atmosphere at that time, but also are one of the important characteristics for predicting future weather changes. Correct observation and analysis of cloud changes is an important factor to understand atmospheric physical conditions and master the law of weather changes. The generation and change of clouds are very complicated. Like anything else, it contains its own special contradictions, thus forming a colorful appearance and rapidly changing characteristics. Only by mastering these characteristics of clouds can we correctly identify clouds and continuously improve the observation level of clouds. The appearance characteristics of clouds are ever-changing, and the reasons for their formation are different, but they all have the same characteristics. According to their similarity and actual needs, clouds are usually divided into three groups according to their base height, and then divided into ten genera and several categories according to their appearance characteristics, structure and nuclear origin. Clouds belong to the category of clouds: low cumulus, light cumulus, cumulus, cumulus, bald cumulus, cumulus, stratocumulus in translucent stratocumulus, stratocumulus in lenticular stratocumulus, stratocumulus in nimbostratus, nimbostratus and cumulus in broken rain layer. Light altocumulus translucent altocumulus high altitude cirrus cirrus dense cirrus pseudocirrus hook cirrus cirrostratus Mao cirrostratus thin curtain cirrostratus cirrostratus cirrostratus low clouds are mostly composed of water droplets, while thick or vertically developing low clouds are composed of water droplets, supercooled water droplets and ice crystals. The height of cloud bottom is generally below 2500 meters, but it varies with seasons, weather conditions and different geographical latitudes. Most low clouds are likely to produce precipitation, and there is often continuous precipitation in nimbostratus. Cumulonimbus clouds often have intermittent precipitation, sometimes very heavy. Cumulus cumulus individuals are obvious, the bottom is flat, the top is convex, and the clouds are mostly unconnected; Clouds formed by air convection and water vapor condensation. Cumulonimbus clouds are thick and big, much like towering mountains. The top has begun to freeze, showing white, vague outline and some fibrous structures. The bottom is very dark, and there are often rain banners hanging down or broken rain clouds. Cumulonimbus clouds are mostly composed of water droplets, supercooled water droplets, ice crystals, snowflakes, and sometimes scattered particles and hail. In the cloud, there is a strong ascending and descending airflow area, and the ascending and descending airflow with a speed of tens of meters per second can be observed, and there are often ups and downs in the cloud bottom. Cumulonimbus cloud is the peak stage of convection development. Mature cumulonimbus clouds often produce strong formation precipitation, which may be accompanied by strong winds, lightning and other phenomena, sometimes hail, and occasionally tornadoes. Stratocumulus clouds are generally very large, with great differences in thickness and shape, some in strips, some in blocks and some in groups. Usually grayish white or gray, with loose structure. Thin clouds can tell the position of the sun, while thick clouds are relatively dark. Clouds are often arranged in rows or waves. The thickness of stratocumulus is usually between several hundred meters and two thousand meters. Most of them are composed of water droplets with a diameter of 5-40 microns. Cumulonimbus clouds that appear in winter may also be composed of ice crystals or snowflakes. In most cases, stratocumulus is formed by the condensation of water vapor due to the mixing of air fluctuation and turbulence. Sometimes it is formed by intense radiation cooling. Generally speaking, it means that the weather is relatively stable, but the stratocumulus gradually thickens and even merges into layers, which means that the weather will change. Low and thick stratocumulus clouds often produce precipitation. Stratocumulus clouds are evenly layered, gray and foggy, and the cloud bottom is very low but does not touch the ground. Stratospheric clouds are generally composed of water droplets or supercooled water droplets with a diameter of 5-30 microns. The thickness is generally 400-500m. Stratosphere is formed by intense radiation cooling or turbulent mixing, water vapor condensation or fog lifting when the gas layer is stable at night. Stratospheric clouds often dissipate after sunrise because the temperature rises and the stable layer is destroyed. Sometimes it rains in Mao Mao and it snows in rice. Nimbostratus, nimbostratus, is low and shapeless, and the clouds are evenly layered, which can completely cover the sun and the moon. It is dark gray or grayish white, and the bottom of the clouds is often accompanied by broken rain clouds. Clouds are widely distributed horizontally, often covering the whole day. The thickness of the cloud is 4000-5000 meters. The lower part of nimbostratus is generally composed of water droplets or supercooled water droplets. The upper part of the northern nimbostratus is often composed of ice crystals or snow crystals. Nimbostratus mostly occurs in warm front clouds (sometimes in other weather systems), which is formed by the upward sliding and adiabatic cooling of the whole wet air system. It often causes long-term continuous precipitation. The agricultural proverb "When the sky is covered with gray cloth, the rain will continue" refers to the precipitation situation in nimbostratus. Most of the clouds in the middle cloud are composed of water droplets, supercooled water droplets, ice crystals or their mixture, and some of the altocumulus clouds can also be composed of a single water droplet. The height of the cloud bottom is usually between 2500 and 5000 meters. High-level clouds often produce precipitation, while thin cumulus clouds generally do not produce precipitation. High-level clouds are evenly distributed, grayish white or gray, and the cloud bottom is often in a strip structure, which often appears in the frontal cloud system and often covers the whole day. High-level clouds are generally composed of water droplets with a diameter of 5-20 microns, supercooled water droplets, ice crystals and snow crystals. Ultra-high cumulus clouds are small in size and well-defined, with great differences in thickness and layers. Thin clouds are white, and the outlines of the sun and the moon can be seen. Thick clouds are dark gray, and the outlines of the sun and the moon can't be seen clearly. Dense cloud bands, often oblate, tiled, fish-scale or wavy. Cumulus clouds consist of water droplets or water droplets mixed with ice crystals. Sunlight and moonlight penetrate through thin cumulus clouds, and are often diffracted to form halos or flowers with red inside and outside. The cause of formation of altocumulus is similar to that of stratocumulus. Thin cumulus clouds are stable and rarely change, which generally indicates sunny days. There is a folk saying that "Wayun will burn people" and "there is no need to turn over the carp in the sky". If the thick cumulus clouds continue to thicken and merge into layers, it means that the weather will change and even precipitation will occur. High clouds are all made up of tiny ice crystals. The height of the cloud bottom is usually more than 5000 meters. Generally, high clouds do not produce precipitation. In winter, it occasionally snows in cirrostratus and Cirrus in the north, and sometimes you can see snow banners. Cirrus clouds have fibrous structure, usually white, shadowless, silky luster, mostly strip, flake, feather, hook, ball and so on. Cirrus clouds are composed of ice crystals. Clouds in the cirrostratus are evenly layered, transparent or milky white. Through the clouds, the outlines of the sun and the moon are clear, and objects on the ground are blocked, which often leads to dizziness. The thickening of cirrostratus is decreasing and the system is developing, which indicates that the weather system will have an impact on the stations. Therefore, there is a folk saying that the sun is dizzy in the middle of the night and the moon is dizzy at noon. But if there is no obvious development, even if the cloud cover decreases, the weather will not change obviously in the future. Look at the stars and the moon at night. If you can't see them, there will be a great chance of rain.