When listening to the weather forecast, we often hear the forecast of "meteorological grade of forest fire danger" The meteorological grade forecast of forest fire danger is a meteorological forecast of the possibility of forest fire. Meteorological conditions are one of the decisive factors for the occurrence and spread of forest fires, and it is of great significance to predict the insurance level of forest fires to prevent the occurrence of fires.

Liangshan, located near the Tropic of Cancer, has a subtropical monsoon climate. Affected by the temperature difference between land and sea in summer, the southeast wind is warm and humid, the winter is affected by the Siberian cold wind, and the northwest wind is dry. This kind of climate background makes Liangshan have obvious dry and wet seasons, abundant sunshine, less rainfall and warm winter. Trees in the forest, especially dry branches and fallen leaves, should be "baked" dry. In addition, Liangshan is located between the basin and the plateau, and Linggu Mountain and Linggu Mountain are integrated with each other. The special terrain makes it have its own local microclimate of 3354 dry-hot valley climate, which is easy to form foehn wind and mountain wind. Both winds are dry and hot. High temperature, low humidity and dry forest, coupled with dry and hot air, are prone to fire. The reporter learned that the conversion frequency of Liangshan forest in Sichuan Climate Center reaches 92 times a year, mostly in winter and spring.

The classification of meteorological grades of forest fire danger is an important basis for forest fire prevention management.

Grade I: low temperature, high relative humidity, wet forest area, not easy to burn. There is no fire risk, so it is not easy to have a fire.

Grade II: The temperature is not high, the relative humidity is high, the forest area is humid, and it is not easy to burn. Due to the low fire risk level, the fire caused by kindling spreads slowly after burning. But patrol should be strengthened, just in case.

Grade III: The humidity is not high, the forest area is dry, it is easy to catch fire and may spread. It is a medium fire risk, which is easy to cause fire and spread quickly. It is necessary to strengthen patrol and surveillance, and it is strictly forbidden to smoke, hunt and other behaviors that are easy to cause fires in forest areas.

Level 4: low humidity, strong wind, dry forest area, easy to catch fire and spread. It belongs to advanced fire risk, which is easy to cause fire and spread quickly. It is necessary to strengthen patrols, prepare for fire fighting, and strictly control all parks.

Grade 5: high temperature, dry forest area, easy to catch fire and spread quickly. Super fire risk is easy to cause fire and spread rapidly. Extraordinary fire prevention measures must be taken, closely monitored day and night, and all gardens must be strictly controlled.