When it is winter in the Northern Hemisphere, the Southern Hemisphere faces the Sun more directly and thus experiences warmer temperatures than the Northern Hemisphere. Conversely, winter in the Southern Hemisphere occurs when the Northern Hemisphere is tilted more toward the Sun. During our summer, the Northern Hemisphere leans toward the sun in its revolution, there are more daylight hours, and the sun's angle is more perpendicular to us than at other times of year. The longer days and more concentrated sunlight and results in more heating. It is all about the tilt of the Earth's axis. Many people believe that the temperature changes because the Earth is closer to the sun in summer and farther from the sun in winter. In fact, the Earth is farthest from the sun in July and is closest to the sun in January.

During the summer, the sun's rays hit the Earth at a steep angle. The light does not spread out as much, thus increasing the amount of energy hitting any given spot. Also, the long daylight hours allow the Earth plenty of time to reach warm temperatures. Regions of earth are colder in the winter because the tilt of the earth causes the sunlight to be spread over a larger area and therefore be weaker per unit area in these regions.“In the right winter weather conditions, you can sustain sun damage just as easily as during the summer.” UVB rays, the main cause of sunburn, are the strongest in the summer. However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as snow or ice. Near the south pole and the north pole, the sun is always very low in the sky, and the sunlight always comes in at a very low angle. As a result, the poles are generally very cold. In contrast, near the equator, the sun is always high in the sky around noon and the sunlight is very direct. This is because the Southern Hemisphere has significantly more ocean and much less land; water heats up and cools down more slowly than land. The differences are also attributed to oceanic heat transfer and differing extents of greenhouse trapping.

The northern hemisphere receives less sunlight per unit area when it is tilted away from the sun and experiences the cold of winter. At the same time, the southern hemisphere is receiving more sunlight per unit area because it is tilted towards the sun and experiences the heat of summer. When it is winter in the Northern Hemisphere, the Southern Hemisphere faces the Sun more directly and thus experiences warmer temperatures than the Northern Hemisphere. Conversely, winter in the Southern Hemisphere occurs when the Northern Hemisphere is tilted more toward the Sun. As the earth travels around the sun during the year it maintains this tilt. Because of this tilt, in the summer we are slanted more directly towards the sun so it's hotter. In the winter, we're slanted away so the sun's rays are less direct, making it colder. The cold weather season is characterized by low temperature and high pressure, and dry climatic conditions. Rainfall occurs in Tamil Nadu because of the northeast trade winds. Western cyclonic disturbance causes rainfall in the north and northwestern parts of India. The cold weather season starts in India in early December and lasts up to February. January and February are the coldest months. Then temperature remains cool and dry. It is cool because the sun's rays do not fall directly.