Downhill fire, also called sitting fire, refers to the fire that spreads from mountain to mountain. Due to the influence of mountain wind, the downhill fire at night is downwind fire. Although the fire going down the mountain at night is faster than during the day, it is far less rapid than the mountain fire during the day, and it spreads slowly and is easy to put out. The downhill fire in the daytime is restrained by the valley wind, belonging to the headwind fire, and its spreading speed is lower than that of the upper mountain fire, which is one of the reasons why it is easy to put out the downhill fire in the daytime.
Related introduction:
Mountain fire, also known as rushing fire, refers to the fire that spreads from the foot of the mountain to the mountain. As the saying goes, fire flows upward and water flows downward. Due to the effect of the valley wind, the mountain fire in the daytime is downwind, spreading fast, fierce and difficult to put out.
The speed of the mountain fire is directly proportional to the slope. The greater the slope, the faster the firing rate, and the speed will double for every increase of 20. The mountain fire at night is constrained by the mountain wind and is a headwind fire. Its spreading speed is much lower than during the day, and the mountain fire at night is not easy to spread to the top of the mountain, which is one of the reasons why the mountain fire at night is easy to be put out.