In what range of temperatures will there be frost?

There will be frost when the ground temperature is below 0℃. When the water vapor in the air near the ground reaches saturation and the ground temperature is lower than 0°C, the white ice crystals that condense directly on the object are not necessarily frost when there is frost.

If the temperature is lower than the ground and water vapor condenses into white crystals on the surface of objects, it is hoar frost; if the water vapor content is low and there is no frost, it is called black frost; if there is freezing damage to crops, it is called frost. ?

Frost is a relatively common agricultural meteorological disaster. It occurs in winter and spring. It is mostly caused by a cold wave moving south and the temperature dropping sharply below zero degrees Celsius in a short period of time; or after being affected by a cold wave, the weather changes from cloudy to cloudy. On the night when it cleared up, it was caused by strong radiation cooling from the ground.

Extended information:

Frost prevention methods:

1. Water spraying method: Garden plants in a small area can use the water spraying method, that is, before the frost comes, the water spraying method can be used. For 1 hour, spray water on the plants continuously. Spraying water can increase the air humidity and temperature (heating the air by about 2°C), thus preventing frost.

2. Covering method: Using straw, wheat straw and other covering plants to prevent the invasion of cold air, while reducing heat loss and increasing the temperature by 1℃-2℃. In addition, for dwarf seedlings, the soil burial method can be used, but this method is only suitable for frost in small areas.

3. Fertilization method: Apply semi-rotted organic fertilizer as base fertilizer 3 to 4 days before frost to increase soil temperature. Commonly used warm fertilizers include manure, compost and plant ash.

Reference: Baidu Encyclopedia-Frost