What does the weather forecast say?

Weather forecast is to predict the weather conditions in a certain period in the future by applying the law of atmospheric change and according to the current and recent weather situation. It is based on the analysis of satellite cloud images and weather maps, combined with the comprehensive study of meteorological data, terrain and seasonal characteristics, and mass experience. For example, the satellite cloud image of China Central Meteorological Observatory was taken by Fengyun-1 meteorological satellite made in China. Using satellite cloud images for analysis can improve the accuracy of weather forecast. The time limit of weather forecast is usually divided into three types: short-term weather forecast (2~3 days), medium-term weather forecast (4~9 days) and long-term weather forecast (10~ 15 days or more). CCTV mainly broadcasts short-term weather forecast every day.

The weather types reported are as follows:

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 2.5mm. ..

Medium 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.