December ushers in the summer season in Buenos Aires, with temperatures averaging 28°C – 32°C (82°F - 90°F). The weather can get very hot, especially in the latter stages of the month closer to Christmas and New Year's. It's not uncommon for temperatures to soar to 35°C (95°F).

The city can become quieter as many locals head to coastal destinations for their summer vacations. However, Buenos Aires remains lively with numerous holiday events and festivities. The heat is often accompanied by high humidity, making air-conditioned spaces a welcome relief.

• Clothing: Light and breathable clothing, hats, and sunscreen are essential. Pack a light jacket for the occasional cooler evening.
• Activities: Enjoy the city's holiday lights, festivals, and open-air events. Stay hydrated and take breaks in air-conditioned spaces to escape the heat.