龙卷风是一种强烈的、小范围的空气涡旋，是在极不稳定天气下由空气强烈对流运动而产生的，由雷暴云底伸展至地面的漏斗状云(龙卷)产生的强烈的旋风，其风力可达12级以上，最大可达100米每秒以上，一般伴有雷雨，有时也伴有冰雹。
空气绕龙卷的轴快速旋转，受龙卷中心气压极度减小的吸引，近地面几十米厚的一薄层空气内，气流被从四面八方吸入涡旋的底部。并随即变为绕轴心向上的涡流，龙卷中的风总是气旋性的，其中心的气压可以比周围气压低百分之十。
龙卷风是一种伴随着高速旋转的漏斗状云柱的强风涡旋。龙卷风中心附近风速可达100m/s～200m/s，最大300m/s，比台风近中心最大风速大好几倍。中心气压很低，一般可低至400hPa，最低可达200hPa。它具有很大的吸吮作用，可把海(湖)水吸离海(湖)面，形成水柱，然后同云相接，俗称“龙取水”。由于龙卷风内部空气极为稀薄，导致温度急剧降低，促使水汽迅速凝结，这是形成漏斗云柱的重要原因。漏斗云柱的直径，平均只有250m左右。龙卷风产生于强烈不稳定的积雨云中。它的形成与暖湿空气强烈上升、冷空气南下、地形作用等有关。它的生命史短暂，一般维持十几分钟到一二小时，但其破坏力惊人，能把大树连根拔起，建筑物吹倒，或把部分地面物卷至空中。江苏省每年几乎都有龙卷风发生，但发生的地点没有明显规律。出现的时间，一般在六七月间，有时也发生在8月上、中旬。
Tornado is a strong, small-scale air vortex is extremely unstable weather from the air campaign have strong convection, clouds from thunderstorms stretching to the ground at the end of the funnel cloud (Tornado) have a strong whirlwind, Its wind up 12 more, up to 100 meters per second over, the general with thunderstorms, sometimes accompanied by hail.
Tornado air around the axis rapid rotation, the Tornado central pressure decreases extremely attracted tens of meters thick near the surface of a thin layer of air, the air is inhaled from all sides of the scroll at the bottom. And then up into the swirl around the axis, the wind always Tornado of the cyclone, its central pressure than the surrounding air pressure low 10 percent.
A tornado is accompanied by a high-speed rotation of the funnel cloud, in strong wind vortex. Tornado wind speed near the centre up to 100 m / s ~ 200m / s, the largest 300 m / s, near the typhoon center than the maximum wind speed good times. Central pressure is very low, generally as low as 400 hPa, the minimum up to 200 hPa. It has GREat sucking, can be the (lake) water suction from the sea (lake) side of a water column, and then with the cloud phase grounding, commonly known as "water dragon." As tornadoes internal air is extremely thin, leading to a sharp decrease temperature, water vapor to the rapid condensation, this is a funnel cloud, in the important reasons. Funnel cloud, in diameter, an average of only 250 m around. Tornadoes have a strong instability in the cumulonimbus of. Its formation was strong and warm air rising, cold air south, the role of the terrain. It's a short-lived, the general maintenance of more than 10 minutes to 12 hours, but its destructive power alarming, can uprooted trees, buildings blown over, some of the ground or to the volume of air. Jiangsu Province, almost all tornadoes occur each year, but the location did not significantly laws. The time, usually in June and July, sometimes in August, the middle.
Tornado air around the axis rapid rotation, the Tornado central pressure decreases extremely attracted tens of meters thick near the surface of a thin layer of air, the air is inhaled from all sides of the scroll at the bottom. And then up into the swirl around the axis, the wind always Tornado of the cyclone, its central pressure than the surrounding air pressure low 10 percent.
A tornado is accompanied by a high-speed rotation of the funnel cloud, in strong wind vortex. Tornado wind speed near the centre up to 100 m / s ~ 200m / s, the largest 300 m / s, near the typhoon center than the maximum wind speed good times. Central pressure is very low, generally as low as 400 hPa, the minimum up to 200 hPa. It has GREat sucking, can be the (lake) water suction from the sea (lake) side of a water column, and then with the cloud phase grounding, commonly known as "water dragon." As tornadoes internal air is extremely thin, leading to a sharp decrease temperature, water vapor to the rapid condensation, this is a funnel cloud, in the important reasons. Funnel cloud, in diameter, an average of only 250 m around. Tornadoes have a strong instability in the cumulonimbus of. Its formation was strong and warm air rising, cold air south, the role of the terrain. It's a short-lived, the general maintenance of more than 10 minutes to 12 hours, but its destructive power alarming, can uprooted trees, buildings blown over, some of the ground or to the volume of air. Jiangsu Province, almost all tornadoes occur each year, but the location did not significantly laws. The time, usually in June and July, sometimes in August, the middle.
