When the temperature drops to what degree, frost may appear?

When the temperature drops below zero, there may be frost.

Frost will appear in autumn, winter and spring. Frost refers to the sudden drop of temperature, and the surface temperature drops below 0℃, causing damage to crops and even death.

3. Frost is different from frost. Frost is a white ice crystal that condenses directly on objects when the water vapor in the air near the ground reaches saturation and the ground temperature is lower than 0℃. When there is frost, it is not necessarily frost. The first frost in autumn is called the first frost, and the last frost in spring is called the final frost, which has a great influence on crops.

Frost is a common agricultural meteorological disaster, which occurs in winter and spring, and is mostly caused by the cold wave heading south and the temperature dropping sharply below zero degrees Celsius in a short time. Still affected by the cold wave, the weather changed from cloudy to sunny that night, which was caused by strong radiation cooling on the ground. This is what people often say "adding insult to injury".