Monthly climate guide
San Juan weather in January
With highs near 32°C (89°F) and lows around 17°C (63°F), January feels hot in San Juan. Rainfall averages about 24 mm (fairly dry) and the sky is a mix of sun and cloud. Daytime highs are about the same as December and about the same as February.
What stands out in January
- Seasonally, January counts as mid-summer in San Juan — the seasons are reversed south of the equator.
- Expect more cloud than at any other time of year.
- Just 290 km apart, but San Juan runs about 2°C cooler than La Rioja this month.
- Afternoons and nights feel like different seasons, roughly 14°C apart.
January is typically San Juan's warmest month.
Avg high
32°C
89°F
Avg low
17°C
63°F
Rainfall
24 mm
fairly dry
Humidity
41%
relative
Sky
38%
cloud · a mix of sun and cloud
San Juan weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 32°C / 89°F | 17°C / 63°F | 24 mm | 41% | 38% |
| February | 30°C / 87°F | 16°C / 61°F | 35 mm | 46% | 37% |
| March | 28°C / 82°F | 14°C / 56°F | 15 mm | 46% | 33% |
| April | 25°C / 76°F | 10°C / 51°F | 6 mm | 48% | 36% |
| May | 21°C / 70°F | 7°C / 44°F | 3 mm | 45% | 44% |
| June | 19°C / 66°F | 4°C / 39°F | 2 mm | 36% | 34% |
| July | 18°C / 65°F | 3°C / 38°F | 2 mm | 36% | 34% |
| August | 21°C / 70°F | 5°C / 40°F | 2 mm | 31% | 29% |
| September | 24°C / 74°F | 7°C / 44°F | 2 mm | 33% | 29% |
| October | 26°C / 79°F | 9°C / 49°F | 5 mm | 34% | 35% |
| November | 29°C / 84°F | 13°C / 55°F | 27 mm | 35% | 32% |
| December | 31°C / 89°F | 16°C / 60°F | 23 mm | 36% | 29% |
What to pack for January
- Light, breathable clothing (cotton or linen)
- A sun hat and high-SPF sunscreen
- A refillable water bottle
- An extra layer — evenings are noticeably cooler than afternoons
- Sunglasses
Is January a good time to visit San Juan?
Compare the months in the chart above to find your ideal window.
Best time to visit San Juan →Other Argentina cities in January
Cite or embed this data
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San Juan weather in January. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/argentina/san-juan/january
<a href="https://weathercompare.eu/weather/argentina/san-juan/january">San Juan weather in January</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/argentina/san-juan" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="San Juan weather in January"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/argentina/san-juan/january">San Juan weather in January</a> – WeatherCompare</p>
San Juan in January: quick answers
Is January a good time to visit San Juan?
It can be, if you like heat: January highs in San Juan are around 32°C. Good for the beach; plan sightseeing for early morning and evening.
How warm is San Juan in January?
Average highs are about 32°C (89°F) and average lows about 17°C (63°F), based on 10 years of daily data.
Does it rain a lot in San Juan in January?
San Juan typically gets around 24 mm of rain in January — fairly dry.
Figures are long-term averages for the area around San Juan (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.