Climate averages 1991–2020
Porto Alegre weather
in May.
A mild, wet month: the 9th warmest and the 2nd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a mild month in Porto Alegre: daytime highs average 21.1°C and nights cool to about 13.2°C. By daytime temperature it is the 9th warmest of the 12 months.
Expect about 107 mm of rain on roughly 9 days, which makes May a wet month (the 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 38 min on an average May day.
The nearest other city in this atlas is Guaíba (13 km away). In May its highs average 21.1°C, about as warm as Porto Alegre, with 107 mm of rain.
Among the 448 cities listed in Brazil, Porto Alegre ranks joint 400th of 448 for the warmest May highs and joint 323rd of 448 for the driest May (rainfall, lowest first). The mean May high of those 448 cities is 25.3°C; Porto Alegre is 4.2°C cooler than that mean.
From May to June, average highs fall by 2.1°C to 19.0°C, and monthly rainfall rises from 107 mm to 113 mm.
The annual picture
May in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Porto Alegre climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.2°C20.6°C | 20.6°C | 137 | 14.0 | 13.814 h |
| February | 28.8°C20.6°C | 20.6°C | 128 | 13.5 | 13.213 h |
| March | 27.5°C19.3°C | 19.3°C | 111 | 11.9 | 12.312 h |
| April | 24.9°C16.5°C | 16.5°C | 106 | 9.2 | 11.411 h |
| May, selected | 21.1°C13.2°C | 13.2°C | 107 | 9.2 | 10.611 h |
| June | 19.0°C10.8°C | 10.8°C | 113 | 9.2 | 10.210 h |
| July | 18.4°C9.8°C | 9.8°C | 140 | 10.0 | 10.410 h |
| August | 20.6°C11.0°C | 11.0°C | 120 | 10.2 | 11.011 h |
| September | 21.6°C12.8°C | 12.8°C | 146 | 11.1 | 11.912 h |
| October | 23.8°C15.2°C | 15.2°C | 170 | 12.4 | 12.813 h |
| November | 26.0°C16.8°C | 16.8°C | 122 | 10.9 | 13.614 h |
| December | 28.4°C19.2°C | 19.2°C | 124 | 11.8 | 14.014 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Guaíba in MayBrazil · 13 kmHigh 21.1°C · Low 13.3°C · 107 mm rain
- Canoas in MayBrazil · 14 kmHigh 21.1°C · Low 13.1°C · 107 mm rain
- Alvorada in MayBrazil · 15 kmHigh 21.1°C · Low 13.3°C · 106 mm rain
- Viamão in MayBrazil · 21 kmHigh 20.6°C · Low 13.4°C · 106 mm rain
- Gravataí in MayBrazil · 25 kmHigh 21.0°C · Low 12.9°C · 106 mm rain
- São Leopoldo in MayBrazil · 31 kmHigh 21.1°C · Low 12.8°C · 120 mm rain
- Novo Hamburgo in MayBrazil · 41 kmHigh 20.8°C · Low 12.1°C · 120 mm rain
- Sapiranga in MayBrazil · 49 kmHigh 21.2°C · Low 13.0°C · 116 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Porto Alegre) is explained once on the Porto Alegre year overview and on the Sources, method and limits page.
Canoas and Guaíba lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.