What are the symbols for weather?

Sunny day: the cloud cover in the sky is less than 30%.

Yin: The amount of clouds in the sky accounts for more than 90%.

Fog: A large number of tiny water droplets or ice crystals float in the air near the ground, and the horizontal visibility drops below 1 km, which affects transportation.

Light rain: the daily precipitation is less than 10 mm.

Heavy rain: the daily precipitation is 25.0-49.9mm..

Thunderstorm: Intermittent precipitation accompanied by lightning and thunder.

Hail: With the violent vertical movement in the cumulonimbus cloud, small hail nuclei repeatedly rise, condense, fall and melt, and grow into small ice cubes with transparent layers.

Have an impact on crops.

Freezing rain: raindrops freeze on the ground below 0℃, also known as rain songs (frozen by fog drops, called fog songs), which often fall off from power lines, making

The road surface is frozen, which affects communication, power supply and traffic.

Sleet: The temperature near the ground is slightly higher than 0℃, and wet snow or rain and snow drop at the same time.

Xiaoxue: The daily snowfall (melting into water) is less than 2.5 mm. 。

Snow: The daily snowfall (melting into water) is 2.6-4.9 mm. 。

Heavy snow: the daily snowfall (melting into water) reaches or exceeds 5.0 mm.

Frost: white frost appears when water vapor condenses into white crystals on the ground and the surface of objects below 0℃. Those with low water vapor content and no frost are called black frost pairs.

All crops have freezing injury, which is called frost.

Low-pressure trough and high-pressure ridge: on the fluctuating high-altitude westerly airflow, the trough corresponds to the low-pressure trough, and the warm air in front of the trough is active in rainy and snowy weather.

After the cold air is controlled, the wind cools the weather; The peak corresponds to the ridge of high pressure and the sky is clear.

Cold and warm fronts: A cold front is the front of cold air. At the intersection of cold and warm air, cold air pushes towards warm air. There are many stormy days on the cold front.

Gas, windy weather in the front after; On the contrary, it is a warm front, the front is rainy, and it turns cloudy and sunny after the front, and the temperature rises.

Strong wind: expressed by wind vector, it consists of wind pole and wind plume. The wind pole refers to the direction of the wind, with eight directions. Cyclone flow is represented by 3 or 4 short strokes and triangles.

The force of strong wind is perpendicular to the right side of the end of the mast (northern hemisphere).