Climate averages 1991–2020
Petrolina weather
by month.
See how the year changes. October has the highest average daily maximum; September has the lowest average monthly rainfall.
Pleasant-weather months by our simple rule: July
Long-term climate patterns, not a forecast for a particular trip.
Across the year Petrolina averages a daytime high of 31.8°C and a nighttime low of 21.7°C, with about 368 mm of rain on roughly 49 days. October is the warmest month (average high 34.0°C) and July the coolest (29.0°C). January is the wettest month with 80 mm; September is the driest with 1.0 mm.
Months with pleasant weather by a simple rule (average high between 18°C and 29°C, average low of at least 5°C and at most 8 rain days): July. This looks at temperature and rain only, not humidity, wind, sea temperature or crowds.
The annual picture
A year in Petrolina
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
Petrolina climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 32.6°C23.0°C | 23.0°C | 80 | 8.7 | 12.613 h |
| February | 32.3°C22.9°C | 22.9°C | 67 | 9.5 | 12.412 h |
| March | 32.1°C22.9°C | 22.9°C | 79 | 10.1 | 12.212 h |
| April | 31.9°C22.6°C | 22.6°C | 32 | 6.0 | 11.912 h |
| May | 31.0°C21.8°C | 21.8°C | 10 | 2.0 | 11.712 h |
| June | 29.5°C20.6°C | 20.6°C | 3.4 | 0.7 | 11.612 h |
| July | 29.0°C19.6°C | 19.6°C | 2.8 | 0.4 | 11.612 h |
| August | 30.1°C19.4°C | 19.4°C | 1.2 | 0.2 | 11.812 h |
| September | 32.4°C20.3°C | 20.3°C | 1.0 | 0.1 | 12.012 h |
| October | 34.0°C21.8°C | 21.8°C | 10 | 1.5 | 12.312 h |
| November | 33.8°C22.8°C | 22.8°C | 32 | 3.9 | 12.513 h |
| December | 33.4°C23.2°C | 23.2°C | 50 | 6.2 | 12.713 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
Nearby cities
- Casa NovaBrazil · 58 kmHigh 32.0°C · Low 22.5°C · 434 mm rain a year
- Senhor do BonfimBrazil · 123 kmHigh 27.7°C · Low 19.3°C · 693 mm rain a year
- Campo FormosoBrazil · 125 kmHigh 27.6°C · Low 19.4°C · 693 mm rain a year
- JacobinaBrazil · 198 kmHigh 27.9°C · Low 19.9°C · 654 mm rain a year
- AraripinaBrazil · 203 kmHigh 29.6°C · Low 20.4°C · 767 mm rain a year
- Paulo AfonsoBrazil · 251 kmHigh 31.3°C · Low 21.5°C · 288 mm rain a year
- IrecêBrazil · 259 kmHigh 29.4°C · Low 19.4°C · 473 mm rain a year
- CratoBrazil · 269 kmHigh 31.0°C · Low 21.7°C · 678 mm rain a year
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 limitsWhat do the high and low temperatures mean?
We average the daily maximum and daily minimum for each calendar month over 1991–2020. They are not record extremes, a forecast range or temperatures at a fixed time of day.
How is a rain day counted?
A local calendar day (standard time, UTC-3, no daylight saving) with at least 1 mm of total precipitation counts as one rain day. We count these for each year and month, then average across 30 years. The average does not predict which days will be wet.
Where do the numbers come from?
ERA5-Land (temperature) and ERA5 (precipitation) reanalysis from the Copernicus Climate Change Service, read from the Open-Meteo open-data archive. Temperature comes from the 0.1° model cell at -9.40°, -40.50° (0 km from the city centre). Rain comes from the 0.25° cell at -9.50°, -40.50°. These are model estimates, not weather-station readings; coast, hills and city streets can differ.
Does this page show sunshine, humidity or sea temperature?
No. The data used here contain air temperature and precipitation only. Daylight hours are calculated from the city's latitude (sunrise to sunset), not measured sunshine.