Summer in Asunción: How Hot It Gets and How to Stay Cool
October to March is hot, humid and stormy. January's average high is 34 °C, heat waves keep setting new records, and the nights stay warm. Here is the month-by-month weather, what counts as a heat wave, the Ministry of Health's advice and how to plan a summer day in the city.
Asunción weather by month
Official 30-year averages (1991–2020) for the Silvio Pettirossi airport station in Luque, next to Asunción, from the national weather service (DMH) as published in the WMO climate normals. Temperatures in °C.
| Month | Avg high (°C) | Avg low (°C) | Rain (mm) | Days with rain* |
|---|---|---|---|---|
| January | 34.0 | 23.1 | 132.6 | 7.2 |
| February | 33.0 | 22.5 | 146.4 | 6.9 |
| March | 31.9 | 21.5 | 131.3 | 6.8 |
| April | 29.2 | 18.9 | 151.7 | 7.6 |
| May | 24.9 | 15.5 | 134.1 | 7.0 |
| June | 23.5 | 14.2 | 70.7 | 4.2 |
| July | 23.6 | 12.9 | 48.2 | 4.1 |
| August | 26.2 | 14.6 | 38.7 | 2.9 |
| September | 27.9 | 16.5 | 79.2 | 4.8 |
| October | 30.1 | 19.5 | 157.9 | 8.2 |
| November | 31.2 | 20.3 | 195.0 | 8.2 |
| December | 32.8 | 22.2 | 176.5 | 7.2 |
*Days with rain: DMH aeronautical climate table, 2011–2023.
January is the hottest month, with December and February close behind. November is the wettest, at 195 mm. June and July are the coolest, and August the driest. Even in the wettest months, rain falls on about eight days: summer rain comes as short, heavy storms.
How hot it gets: averages versus heat waves
The national weather service defines a heat wave as at least three days in a row when both the daily high and the daily low stay above a local threshold. For Asunción that is 37 °C and 25 °C; an extreme heat wave starts at 38 °C and 26 °C. Warm nights are part of the definition, which is why a heat wave feels relentless: the city doesn't cool down after dark.
In February 2026, Asunción set new daily records on February 18 and February 19, the second beating a mark that had stood for 21 years. By February 19, the city was on day four of a heat wave.
What the heat feels like
Humidity makes it worse: damp air keeps sweat from cooling you. Forecasts quote the sensación térmica (feels-like temperature) next to the air temperature, and in a humid heat wave the feels-like figure runs higher. Plan around the feels-like number. The DMH home page shows both for Asunción.
Staying safe in the heat
The Ministry of Health's heat advice:
- Drink plenty of water, even when you're not thirsty.
- Stay out of direct sun from 10:00 to 17:00. Avoid hard physical activity in the sun.
- Keep children and older people somewhere cool and shaded.
- Wear sunscreen of at least SPF 50 (SPF 60 for children and older people).
- Dress for it: a hat, sunglasses, light-colored loose clothing and comfortable shoes.
- Look for shade wherever you can.
Warning signs of heat stroke. Hot, red and sometimes dry skin with little or no sweat; confusion or disorientation; seizures; a fast heartbeat and fast breathing; a severe headache, marked weakness or dizziness. If you see any of these, go to the nearest health service right away and don't self-medicate.
In an emergency, call 911 or the public ambulance service on 141. Our hospitals guide lists emergency rooms.
Planning a summer day in Asunción
On hot days, keep outdoor time to the cool ends of the day.
- Early morning or sunset outdoors. The Costanera is free; go at sunset. For shade, see the parks on our things-to-do page.
- Midday indoors. See our museums guide and what's open on Sunday.
- Tereré. The cold yerba drink is summer in a cup; see our tereré guide, and drink water too.
Summer storms
Summer heat breaks with sudden, heavy rain. On March 16, 2026, Asunción recorded 210.8 mm, smashing a March record that had stood since 1964. Heavy rain turns streets into raudales, fast-running water that makes driving and walking dangerous. Stay off flooded streets, keep away from power poles and downed wires, and wait it out indoors.
Where to check the forecast and heat alerts
The national weather service publishes the Asunción forecast, current conditions with the sensación térmica, weather alerts (avisos) and heat-wave bulletins at meteorologia.gov.py. Our weather links go straight to it.
FAQ
What is the weather like in Asunción by month?
Hot and humid from October to March, with average highs above 30 °C and most of the year's rain. June to August are the coolest and driest months.
How hot does Asunción get in summer?
January averages a high of 34.0 °C. Heat waves go well past that: in February 2026, Asunción set new daily records two days running.
When is winter in Paraguay?
June to August. At the airport station, June has the lowest average high (23.5 °C) and July the lowest average low (12.9 °C).
When is a good time of year to visit Asunción?
For milder weather, June to September is cooler and drier than summer. Summer works too if you plan around the heat: outdoors early or late, indoors at midday.
Does tereré help you stay hydrated?
The Ministry of Health calls tereré refreshing but says it does not hydrate, because of the diuretic effect of the yerba, and recommends drinking water as well.
Too hot to move by day? Join Open Asu on WhatsApp for evening plans when the day is too hot to move.