Climate averages 1991–2020
Bahía Blanca weather
in September.
A mild, moderately wet month: the 8th warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Bahía Blanca: daytime highs average 17.6°C and nights cool to about 8.0°C. By daytime temperature it is the 8th warmest of the 12 months.
Expect about 45 mm of rain on roughly 6 days, which makes September a moderately wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 48 min on an average September day.
The nearest other city in this atlas is Olavarría (265 km away). In September its highs average 16.8°C, 0.8°C cooler than Bahía Blanca, with 62 mm of rain.
Among the 67 cities listed in Argentina, Bahía Blanca ranks 52nd of 67 for the warmest September highs and 20th of 67 for the driest September (rainfall, lowest first). The mean September high of those 67 cities is 19.4°C; Bahía Blanca is 1.8°C cooler than that mean.
From September to October, average highs rise by 3.0°C to 20.6°C, and monthly rainfall rises from 45 mm to 64 mm.
The annual picture
September 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
Bahía Blanca climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.7°C18.7°C | 18.7°C | 54 | 7.1 | 14.515 h |
| February | 28.0°C17.7°C | 17.7°C | 65 | 6.7 | 13.614 h |
| March | 25.3°C16.0°C | 16.0°C | 67 | 6.7 | 12.412 h |
| April | 20.7°C12.2°C | 12.2°C | 55 | 6.0 | 11.111 h |
| May | 16.7°C9.2°C | 9.2°C | 38 | 5.4 | 10.110 h |
| June | 13.4°C6.2°C | 6.2°C | 28 | 4.4 | 9.510 h |
| July | 12.7°C5.0°C | 5.0°C | 34 | 5.0 | 9.710 h |
| August | 15.1°C6.4°C | 6.4°C | 35 | 4.7 | 10.611 h |
| September, selected | 17.6°C8.0°C | 8.0°C | 45 | 6.2 | 11.812 h |
| October | 20.6°C10.9°C | 10.9°C | 64 | 7.7 | 13.113 h |
| November | 24.5°C14.0°C | 14.0°C | 63 | 7.0 | 14.214 h |
| December | 28.0°C16.9°C | 16.9°C | 57 | 6.2 | 14.815 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
September in nearby cities
- Olavarría in SeptemberArgentina · 265 kmHigh 16.8°C · Low 6.4°C · 62 mm rain
- Santa Rosa, Argentina in SeptemberArgentina · 294 kmHigh 18.9°C · Low 8.0°C · 48 mm rain
- Necochea in SeptemberArgentina · 307 kmHigh 14.3°C · Low 7.8°C · 56 mm rain
- Tandil in SeptemberArgentina · 315 kmHigh 16.0°C · Low 5.8°C · 59 mm rain
- Mar del Plata in SeptemberArgentina · 418 kmHigh 14.7°C · Low 7.5°C · 60 mm rain
- General Roca in SeptemberArgentina · 462 kmHigh 18.7°C · Low 7.0°C · 21 mm rain
- Junín in SeptemberArgentina · 473 kmHigh 19.2°C · Low 8.9°C · 67 mm rain
- Cipolletti in SeptemberArgentina · 496 kmHigh 18.5°C · Low 6.7°C · 19 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 Bahía Blanca) is explained once on the Bahía Blanca year overview and on the Sources, method and limits page.