Climate averages 1991–2020
San Juan, Argentina weather
in January.
A hot, fairly dry month: the warmest and the joint 6th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
January is a hot month in San Juan, Argentina: daytime highs average 31.0°C and nights cool to about 19.2°C. By daytime temperature it is the warmest month of the year.
Expect about 17 mm of rain on roughly 3 days, which makes January a fairly dry month (the joint 6th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 57 min on an average January day.
The nearest other city in this atlas is Rawson (5 km away). In January its highs average 30.5°C, about as warm as San Juan, Argentina, with 17 mm of rain.
Among the 67 cities listed in Argentina, San Juan, Argentina ranks joint 11th of 67 for the warmest January highs and joint 5th of 67 for the driest January (rainfall, lowest first). The mean January high of those 67 cities is 29.0°C; San Juan, Argentina is 2.0°C warmer than that mean.
From January to February, average highs fall by 1.2°C to 29.7°C, and monthly rainfall rises from 17 mm to 20 mm.
The annual picture
January 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 Juan, Argentina climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January, selected | 31.0°C19.2°C | 19.2°C | 17 | 3.2 | 13.914 h |
| February | 29.7°C18.0°C | 18.0°C | 20 | 3.4 | 13.213 h |
| March | 27.2°C15.8°C | 15.8°C | 24 | 3.9 | 12.312 h |
| April | 23.2°C11.6°C | 11.6°C | 18 | 3.3 | 11.311 h |
| May | 19.6°C7.6°C | 7.6°C | 10 | 2.6 | 10.511 h |
| June | 17.4°C4.1°C | 4.1°C | 7.8 | 2.0 | 10.110 h |
| July | 16.4°C2.9°C | 2.9°C | 8.2 | 2.2 | 10.310 h |
| August | 19.4°C5.0°C | 5.0°C | 10 | 2.3 | 11.011 h |
| September | 21.8°C8.0°C | 8.0°C | 17 | 3.3 | 11.912 h |
| October | 25.1°C11.8°C | 11.8°C | 21 | 3.5 | 12.813 h |
| November | 28.0°C15.0°C | 15.0°C | 16 | 3.2 | 13.714 h |
| December | 30.3°C17.7°C | 17.7°C | 22 | 3.3 | 14.214 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
January in nearby cities
- Rawson in JanuaryArgentina · 5 kmHigh 30.5°C · Low 18.5°C · 17 mm rain
- Mendoza in JanuaryArgentina · 153 kmHigh 28.4°C · Low 17.8°C · 48 mm rain
- San Martín in JanuaryArgentina · 172 kmHigh 31.3°C · Low 20.0°C · 48 mm rain
- Colina in JanuaryChile · 274 kmHigh 29.7°C · Low 18.3°C · 7.7 mm rain
- Ovalle in JanuaryChile · 275 kmHigh 29.7°C · Low 16.9°C · 0.3 mm rain
- San Luis in JanuaryArgentina · 284 kmHigh 29.7°C · Low 19.2°C · 107 mm rain
- Peñalolén in JanuaryChile · 286 kmHigh 26.8°C · Low 15.9°C · 15 mm rain
- Quilicura in JanuaryChile · 289 kmHigh 28.5°C · Low 16.8°C · 7.7 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 Juan) is explained once on the San Juan, Argentina year overview and on the Sources, method and limits page.
Rawson lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.