What clouds represent what weather?

There are clouds in the sky and rain on the ground.”: Meteorologically, these clouds are called cirrus clouds. They generally appear in front of warm fronts and low pressures. The appearance of cirrus clouds indicates that a front or low pressure is coming. However, when clouds appear after rain or in winter, there will be continuous sunny days or frosts, so there are also "clouds dissipate, sunny days will be dry", and "clouds will cause dust in winter". Proverb.

“Fort clouds, raindrops”: Fort clouds refer to fort-shaped altocumulus clouds or fort-shaped stratocumulus clouds. They often appear in front of low-pressure troughs, indicating unstable air. They usually occur every 8 to 10 hours. Thunderstorm is coming.

“Clouds cross clouds, rain falls”: Clouds cross clouds means that the upper and lower clouds move in different directions, that is to say, the wind direction at the height of the clouds is inconsistent. It often occurs near fronts or low pressures, so it is a warning. When there is rain, sometimes the clouds are in the opposite direction to the wind on the ground, and there is a saying that "the clouds move against the wind, and the sky will change."

"When the river pig crosses the river, it rains heavily": The river pig refers to the raindrops under the clouds. Nimbus, the appearance of this kind of cloud, indicates that there is enough water vapor in the nimbus clouds, and heavy rain is coming. Sometimes broken rain clouds are blown by strong winds to cloudless places, and clouds like river pigs can be seen floating across the "Milky Way" at night. , is also a precursor to rain.

"Cotton cloud, rain is coming": Cotton cloud refers to fluffy altocumulus clouds. The appearance of such clouds indicates that the middle atmosphere is very unstable. If there is sufficient water vapor in the air and there is upward movement. , cumulonimbus clouds will form, and thunderstorms will come.

"The sky is covered with gray cloth, and the rain is continuous." Gray cloth clouds refer to nimbus clouds, which are mostly formed by the lowering and thickening of altostratus clouds. The range is very large and thick, and there is sufficient water vapor in the clouds, often producing continuous precipitation.

“When clouds go east, cars and horses pass; when clouds go south, water swells; If clouds move to the west, they will be covered with raincoats; if clouds move to the north, they will be able to dry out the wheat.": Predict cloudiness and fineness based on the direction of cloud movement. Clouds moving to the east and north indicate fine weather; clouds moving to the west and south indicate good weather. Rain is coming. The direction of cloud movement generally indicates the direction of the wind at its height. This proverb describes the distribution of clouds in different parts of the low pressure. It applies to clouds that are dense throughout the sky and move quickly. p>

"Dark clouds catch the setting sun, and if it does not set today, it will set tomorrow": refers to when the sun sets, a dark cloud like a city wall rises under the western horizon to catch the sun, indicating that the dark clouds are moving eastward, and the rainy weather is moving to the west, and it is about to Rain. Generally speaking, if there are medium clouds, it will rain that night; if there are high clouds, it will rain the next day. But if the dark clouds in the west are in strips or broken, or the local area is cloudy, then it means it will rain. This is not a sign of rain in the future.

"The sky in the northwest is unlocked and the sun is shining brightly": It means that on rainy days, the clouds in the northwest open up and reveal a piece of blue sky, which is called "the sky is unlocked". It is at the rear of the rainy weather system. As the rainy system moves eastward, the local rain will stop and the clouds will disappear, and the weather will improve.

"The sun appears and does not see it for three days": refers to the spring and summer seasons. , at noon on a rainy day, the clouds split and the sun showed its face, but the clouds quickly gathered and thickened, which showed that the local area was under the influence of a quasi-stationary front, and the airflow near the quasi-stationary front rose and fell strongly and changeably. When the updraft strengthens, the clouds thicken and the rainfall increases; when the updraft weakens, the clouds thin and the rainfall decreases or stops; around noon, when the sun shines strongly, the upper part of the cloud layer is heated and evaporates, or the updraft below the cloud layer weakens and the zenith The clouds will split. As the sun's irradiation weakens, or the updrafts below the clouds strengthen, the clouds that have broken apart gather back together and become thicker. Therefore, "the sun appears once and for all" often indicates continued rain. This proverb is similar to the proverbs such as "The sun laughs and rains down the temple" and "When it shines, it falls down a foot".

“There are carp spots in the sky, and you don’t need to turn over the grains to dry them tomorrow” (tile clouds, the sun is so scary): Carp spots refer to light-transmitting altocumulus clouds. The air masses that produce such clouds are stable in nature. At night, when you encounter them, The downdraft will cause the clouds to dissipate quickly, and the weather will be fine the next day. However, if the clouds look like tiny fish scales, they are cirrocumulus clouds. These clouds mostly occur in front of low-pressure troughs or outside typhoons. It will be windy or rainy in the near future, so there is also a "fish-scale sky, even if it doesn't rain, it will be windy" proverb.

“When clouds go east, there is a gust of wind; when clouds go west, they are covered with raincoats”: The clouds referred to here are low clouds in low-pressure areas. Low pressure moves from west to east (actually, it often moves from southwest to northeast). If the clouds move to the west, it means that the local area is in the front of the low pressure, and the local area will rain due to the moving of the low pressure; if the clouds move to the east, it means that the low pressure has moved to the local area, and the local area is in the rear of the low pressure area, and the weather is about to clear up, and there is often a gust of wind before it clears up. .

"Which way does the cloud hook go, and where does the wind come from?": Cloud hook refers to the tail of cirrus clouds, which appears at high altitudes. Sometimes there are small hooks on the upper end, and some are arranged in rows. The small hook at the upper end points to the direction of high-altitude wind, and high-altitude wind is often connected to the ground, so the direction of the wind can be roughly measured based on the direction of the cloud hook.

"Dark clouds cover the sky in the morning, and the wind comes even if there is no rain": It means that there are dark clouds covering the sun in the southeast direction in the morning, which indicates rain. Because the warm and humid southeast wind blows in the morning, the temperature is higher than the local air, causing it to be cold at the top and hot at the bottom. Water vapor easily rises into clouds. In addition, the ground is heated during the day and the air convection rises, which further causes the clouds to rise and the water vapor turns into water droplets when cooled. , which may cause the weather to change from wind to rain.

“The yellow clouds are turning up and down, and ice eggs are about to be laid”: Yellow clouds are mostly caused by the strong rise of warm and humid air. When this happens, showers and hail are likely to fall.

"Mountains wearing hats, heavy rain is coming": Mountains wearing hats means that the air pressure is low, and there is a lot of water vapor in the air forming clouds on the top of the mountain. As for whether it will rain, it generally depends on the situation. If the clouds gradually decrease and thicken, the possibility of rain is high. On the contrary, if the clouds gradually lift and thin, the possibility of rain is small.

“The clouds eat the fog, and the fog eats the clear clouds”: When you see clouds coming after the fog, it may be that low pressure is coming, which is a sign of rain. On the contrary, if the clouds disappear and the fog rises, it means that the low pressure has passed and sunny weather is coming.

"Sunset feet, rain falls within three days": refers to the sun shining down from the gaps in the clouds, called "sunshot feet". The appearance of sunray feet in the evening indicates strong convection and indicates rain.

"Morning glow does not go out, but sunset glow travels thousands of miles": There are no clouds in the east in the morning, and there are clouds in the west. The sunlight shines on the clouds and scatters colorful clouds, indicating that there is abundant water vapor in the air or there is a cloudy and rainy system moving in, and during the day The air is generally unstable and the weather will turn cloudy and rainy; if the sunset glows in the evening, it indicates that the sky in the west has cleared up. In addition, convection generally weakens at night, and the clouds in the east that form colorful clouds will move further east or tend to dissipate, indicating that the sky will be clear. .

“It will be clear for a long time, it will be foggy and cloudy, it will be cloudy and it will be foggy and clear for a long time”: refers to the appearance of fog after a long period of clear weather, indicating that warm and humid air has moved in, and the air is moist, which is a sign of cloudy and rainy weather; after a long period of cloudy weather, fog appears The appearance of fog indicates that the clouds in the sky have thinned, cracked and dissipated, and the ground temperature has dropped, causing water vapor to condense into radiation fog. After sunrise, the fog will disappear and sunny days will appear.

In the morning of the warm season, if fortress-shaped clouds appear on the horizon, it means that the moist air layer at this height is already very unstable. By noon, once low-level convection develops, the unstable layers above and below combine, Strong convective motion will occur, forming cumulonimbus clouds and causing thunderstorms. Hence the proverb, "The pagoda is clouded in the morning, and the rain pours in the afternoon."

In addition, clouds with weather signs often have a certain degree of continuity, seasonality and locality in their evolution. When the clouds in the sky move continuously from a distance in the order of cirrus, cirrostratus, altostratus, and nimbostratus, and gradually change from less to more, from high to low, and from thin to thick, it indicates that a lot of things will happen soon. There will be rainy weather soon; on the contrary, if the clouds change from low to high, from thick to thin, and from layers to scattered clouds, there will be no rainy weather. In warm season mornings, if there are isolated clouds with flat bottoms, convex tops (pale cumulus clouds) or white fragmented clouds that move quickly (cumulus fragments) in the sky, it indicates that the middle and lower air layers are relatively stable and the weather is fine.

In addition, the color of clouds can also predict certain weather conditions. For example, the color of hail clouds is first white on top and black on the bottom, and then red appears in the clouds, forming a mess of white, black, and red cloud filaments. It is earthy yellow in color. Black is caused by the inability of sunlight to penetrate the cloud; white is the result of clouds scattering or reflecting sunlight indiscriminately; red and yellow are caused by certain cloud droplets in the cloud (with a diameter between one thousandth and one hundredth of a millimeter). The phenomenon of selective scattering of sunlight. Sometimes the rain clouds also appear light yellow, but the clouds are even in color and not billowing randomly. There are also many proverbs that predict hail will fall based on the color and shape of clouds. For example, there are proverbs in Inner Mongolia such as "We are not afraid of darkness in the clouds, but we are afraid of black clouds mixed with red, and we are most afraid of white worms growing under yellow clouds." In Shanxi, there is a saying such as "When yellow clouds turn, hail will fall; when clouds are disturbed, hail will swarm; when clouds fight, There are proverbs such as "Hail is going to fall", "Black clouds, yellow clouds, soil and red clouds, the clouds are tossing and turning, and there are many hailstorms that will cause serious disasters". There are also sayings such as "Dark clouds roll into balls in the afternoon, wind, rain and hail come together", "The sky is yellow and muggy, dark clouds roll in, and the Tianhe water roars to prevent ice eggs". These all indicate that when air convection is strong, clouds develop rapidly, like thick smoke. When the ground rushes straight up and the clouds roll up and down and back and forth, hail is likely to fall.