Climate averages 1991–2020
San Martín weather
in September.
A mild, very dry month: the 8th warmest and the 4th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in San Martín: daytime highs average 21.1°C and nights cool to about 8.5°C. By daytime temperature it is the 8th warmest of the 12 months.
Expect about 11 mm of rain on roughly 2 days, which makes September a very dry month (the 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 52 min on an average September day.
The nearest other city in this atlas is Mendoza (41 km away). In September its highs average 18.3°C, 2.8°C cooler than San Martín, with 28 mm of rain.
Among the 67 cities listed in Argentina, San Martín ranks 18th of 67 for the warmest September highs and 1st of 67 for the driest September (rainfall, lowest first). The mean September high of those 67 cities is 19.4°C; San Martín is 1.7°C warmer than that mean.
From September to October, average highs rise by 3.8°C to 24.9°C, and monthly rainfall rises from 11 mm to 20 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
San Martín climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 31.3°C20.0°C | 20.0°C | 48 | 7.7 | 14.114 h |
| February | 29.7°C18.6°C | 18.6°C | 38 | 6.4 | 13.313 h |
| March | 26.7°C16.3°C | 16.3°C | 43 | 6.2 | 12.312 h |
| April | 22.0°C11.9°C | 11.9°C | 20 | 4.3 | 11.311 h |
| May | 17.8°C8.1°C | 8.1°C | 12 | 2.6 | 10.410 h |
| June | 14.9°C4.4°C | 4.4°C | 5.5 | 1.3 | 10.010 h |
| July | 14.5°C3.2°C | 3.2°C | 5.6 | 1.6 | 10.210 h |
| August | 17.7°C5.3°C | 5.3°C | 10 | 1.9 | 10.911 h |
| September, selected | 21.1°C8.5°C | 8.5°C | 11 | 2.3 | 11.912 h |
| October | 24.9°C12.5°C | 12.5°C | 20 | 3.9 | 12.913 h |
| November | 28.4°C16.0°C | 16.0°C | 27 | 5.1 | 13.814 h |
| December | 30.9°C18.8°C | 18.8°C | 39 | 6.7 | 14.314 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
- Mendoza in SeptemberArgentina · 41 kmHigh 18.3°C · Low 6.1°C · 28 mm rain
- Rawson in SeptemberArgentina · 167 kmHigh 21.5°C · Low 7.3°C · 17 mm rain
- San Rafael in SeptemberArgentina · 171 kmHigh 19.4°C · Low 6.3°C · 28 mm rain
- San Juan, Argentina in SeptemberArgentina · 172 kmHigh 21.8°C · Low 8.0°C · 17 mm rain
- Peñalolén in SeptemberChile · 196 kmHigh 16.3°C · Low 4.9°C · 72 mm rain
- San Luis in SeptemberArgentina · 201 kmHigh 21.3°C · Low 9.4°C · 30 mm rain
- Puente Alto in SeptemberChile · 204 kmHigh 17.2°C · Low 3.8°C · 72 mm rain
- Colina in SeptemberChile · 205 kmHigh 18.8°C · Low 7.8°C · 77 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 San Martín) is explained once on the San Martín year overview and on the Sources, method and limits page.