Countries that are in the Southern Hemisphere have summer during the months of December, January and February; these countries include Mexico, Argentina and Brazil. Summer is known to be the warmest season in each of these countries, as well as containing the hottest and longest days of the year, making it an excellent time to travel.
For those people who are looking to travel and vacation in these places, there are several options. The Americas are a great choice for a summer in December, as well as The Caribbean. Some of the most popular destinations for summer in December include: Cartagena, Colombia; Mexico City, Mexico; San Jose, Costa Rica; Lima, Peru; Buenos Aires, Argentina; Queensland, Australia; and Rio de Janeiro, Brazil.
In some locations, there are rainy seasons that often coincide with summer seasons. To avoid these when traveling, research the country's average climate, before planning a trip.