龙卷风是云层中雷暴的产物。具体的说，龙卷风就是雷暴巨大能量中的一小部分在很小的区域内集中释放的一种形式。龙卷风的形成可以分为四个阶段：
（1）大气的不稳定性产生强烈的上升气流，由于急流中的最大过境气流的影响，它被进一步加强。
（2）由于与在垂直方向上速度和方向均有切变的风相互作用，上升气流在对流层的中部开始旋转，形成中尺度气旋。
（3）随着中尺度气旋向地面发展和向上伸展，它本身变细并增强。同时，一个小面积的增强辅合，即初生的龙卷在气旋内部形成，产生气旋的同样过程，形成龙卷核心。
【趣味英语】春节小知
世界节日（1）Spring （4）龙卷核心中的旋转与气旋中的不同，它的强度足以使龙卷一直伸展到地面。当发展的涡旋到达地面高度时，地面气压急剧下降，地面风速急剧上升，形成龙卷。
龙卷风常发生于夏季的雷雨天气时，尤以下午至傍晚最为多见。袭击范围小，龙卷风的直径一般在十几米到数百米之间。龙卷风的生存时间一般只有几分钟，最长也不超过数小时。风力特别大，在中心附近的风速可达100-200米/秒。破坏力极强，龙卷风经过的地方，常会发生拔起大树、掀翻车辆、摧毁建筑物等现象，有时把人吸走，危害十分严重。
The formation of tornadoes
Tornadoes are the product of the clouds of thunderstorms. Specifically, the tornado is tremendous energy in thunderstorms a small part in a small area on a form of release. The formation of tornadoes can be divided into four stages:
(1) the instability of the atmosphere have increased by the strong airflow, as the biggest rapids of the impact of cross-border flow, it has been further strengthened.
(2) As in the vertical direction and speed and direction of the wind shear have interaction, increased airflow in the middle of the troposphere starting rotation, the formation of scale cyclone.
(3) As to the ground in the cyclone-scale development and proGREssive extension, its own thinning and strengthen. At the same time, a small area of the strengthening of Des Voeux, that is the primary form of internal Tornado in the cyclone, a cyclone in the same process, the formation of Tornado core.
(4) Tornado core of the cyclone in the rotation and different, its strength is sufficient to Tornado has been extended to the ground. When the development of the scroll arrived at the high ground, ground sharp decline in air pressure, wind speed sharp rise in the ground, a Tornado.
Tornadoes often occur in the summer lightning storm, especially in the afternoon to the evening most common. The scope of small attacks, tornadoes in the general diameter of 10 meters to 100 meters between. The tornado survival time normally only a few minutes, the longest more than a few hours. Wind particularly in the vicinity of the wind speed up to 100-200 meters / second. Extremely destructive, after the tornado, uprooted trees often happens, overturned vehicles, destroyed buildings, and other phenomena, sometimes people take suction, very serious harm.
Tornadoes are the product of the clouds of thunderstorms. Specifically, the tornado is tremendous energy in thunderstorms a small part in a small area on a form of release. The formation of tornadoes can be divided into four stages:
(1) the instability of the atmosphere have increased by the strong airflow, as the biggest rapids of the impact of cross-border flow, it has been further strengthened.
(2) As in the vertical direction and speed and direction of the wind shear have interaction, increased airflow in the middle of the troposphere starting rotation, the formation of scale cyclone.
(3) As to the ground in the cyclone-scale development and proGREssive extension, its own thinning and strengthen. At the same time, a small area of the strengthening of Des Voeux, that is the primary form of internal Tornado in the cyclone, a cyclone in the same process, the formation of Tornado core.
(4) Tornado core of the cyclone in the rotation and different, its strength is sufficient to Tornado has been extended to the ground. When the development of the scroll arrived at the high ground, ground sharp decline in air pressure, wind speed sharp rise in the ground, a Tornado.
Tornadoes often occur in the summer lightning storm, especially in the afternoon to the evening most common. The scope of small attacks, tornadoes in the general diameter of 10 meters to 100 meters between. The tornado survival time normally only a few minutes, the longest more than a few hours. Wind particularly in the vicinity of the wind speed up to 100-200 meters / second. Extremely destructive, after the tornado, uprooted trees often happens, overturned vehicles, destroyed buildings, and other phenomena, sometimes people take suction, very serious harm.
【趣味英
世界节日
2010年牛
2010年新
圣诞节故事
儿童英语小
