<P> The U.S. Post Office and U.S. Army and Navy officials, in conjunction with the American advertising and greeting card industries, threw a Christmas in July luncheon in New York in 1944 to promote an early Christmas mailing campaign for service men overseas during World War II . The luncheon was repeated in 1945 . </P> <P> American advertisers began using Christmas in July themes in print for summertime sales as early as 1950 . In the United States, it is more often used as a marketing tool than an actual holiday . Television stations may choose to re-run Christmas specials, and many stores have Christmas in July sales . Some individuals choose to celebrate Christmas in July themselves, typically as an intentionally transparent excuse to have a party . This is in part because most bargainers tend to sell Christmas goods around July to make room for next year's inventory . </P> <P> In the Southern Hemisphere, seasons are in reverse to the Northern Hemisphere, with summer falling in December, January, and February, and with winter falling in June, July, and August . Therefore, in some southern hemisphere countries, such as Comoros, Madagascar, Bolivia, Angola, French Polynesia, Papua New Guinea, Paraguay, Samoa and South Africa, Christmas in July or Midwinter Christmas events are undertaken in order to have Christmas with a winter feel in common with the northern hemisphere . These countries still celebrate Christmas on December 25, in their summer, like the northern hemisphere . </P> <P> In the Northern Hemisphere, a Christmas in July celebration is deliberately ironic; the July climate is typically hot and either sunny or rainy, as opposed to the cold and snowy conditions traditionally associated with Christmas celebrations in the higher latitudes of the Northern Hemisphere . Some people throw parties during July that mimic Christmas celebrations, bringing the atmosphere of Christmas but with warmer temperatures . Parties may include Santa Claus, ice cream and other cold foods, and gifts . Nightclubs often host parties open to the public . Christmas in July is usually recognized as July 12 but also sometimes celebrated on July 25 . </P>

Why do the countries in the southern hemisphere celebrate christmas in summer season
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