Thunderstorm form when a warm air mass is forced by a cold mass at a front 当暖气团在锋面处受到冷气团的作用时，就会形成雷暴雨。
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It is during these seasons that the differences in temperature between warm and cold masses of air are greatest 就在这些季节里，热气团与冷气团的温差最大。
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Stratiform clouds are layered clouds formed mainly by uplifting of air on a large scale , commonly seen near a front , which signifies the interface of warm , moist air climbing up cold air on encountering the latter 乌云接日头，半夜雨稠稠的层状云天气：层状云主要由大范围的气流上升运动形成，常见于锋面附近，即暖湿空气碰到冷气团，向上爬升的交界面上。
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However , the motivating force of love pushed us to work more diligently than usual . we meditated , cut grass , loosened the soil and planted trees to keep our bodies warm . as we worked our way up the hill at the center , we had to hang on tightly with both hands and help each other over the steep incline near the hilltop 因为正值寒冬，又逢大陆冷气团过境，浓雾细雨冷风时隐时现，平时习惯温热气候的人，一时之间无法适应这种突如其来的寒冷，可是大家由爱心为出发点，反而更努力打坐割草挖土种树以增强体温适应爬上高山快达到山顶时，大家与山坡几乎成90度的垂直面，必须以双手用力攀登互相拉上去，路又滑跌倒难免，爬下山来时，人人几乎都是滚下来的，许多不习惯爬山的人，双腿筋骨酸痛得寸步难行，然而内心依然满足。
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The occurrence of cirrocumulus clouds indicates the distant presence of a convergent zone such as a pressure tough or a cyclone in lower levels ; or a frontal zone where cold air meets moist warm air . vigorous convection and lifting motion bring water vapour up in the sky where the water vapour sublimes into ice crystals , forming the high clouds 卷积云的出现显示远处地方低层有一强辐合带如低压槽或气旋或锋面即暖湿空气碰到冷气团，向上爬升的交界面形成，强烈的对流和抬升运动将水汽带到高空，在那里水汽直接升华变为冰晶而形成高层云。
