Climate in Paraguay is governed by winds, a north wind bringing high temperatures from the tropics and a south wind bringing cool weather from Patagonia. Paraguay is intensely hot from November to March, averaging 95°F (35°C), with daily temperatures ranging between 77°F to 109°F (25°C to 43°C). It is coolest from April to September, though the average high in July, the coldest month, is 71°F (22°C). At this time, extremely hot days as well as cold morning frosts are not unusual.

The end of June usually experiences a week or two of hot weather, known as the Veranillo de San Juan (St John's minisummer) as it frequently coincides with the Fiesta de San Juan. Heavy rain and breathtaking electric storms are frequent from September to November and, less dramatically, from March to April. Typically the sun shines throughout the year, even when it is cold.